RESUMEN INVESTIGADORES-2

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR 1

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR 2

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR EL COMPROMISO DEL HOSPITAL UNIVERSITARIO Desde los comienzos de la medicina durante el periodo Hipocrático, al momento en que un médico se juramentaba se comprometía a nunca negar el derecho a la enseñanza gratuita a los hijos de nuestros maestros (1). Este compromiso de enseñanza se mantiene hasta hoy en día, ya que todos los médicos continua- mos asumiendo la responsabilidad de generar y transmitir nuevo conocimiento para beneficio de la humanidad. En sus orígenes, la enseñanza de la medicina estaba limitada a la trans- misión de conocimientos del maestro al pupilo y posteriormente a grupos reducidos de estudiantes. Debieron transcurrir dos siglos desde la creación de los hospitales por San Basilio el Grande en Turquía en el siglo IV para que se combinara la enseñanza de la medicina con la atención de enfermos en el hospital de Gundishapur (Irán), primer hospital donde los estudiantes eran autorizados para practicar la medicina bajo la supervisión de tutores (2). Los hospitales europeos del siglo XI y XII contaron con pabellones para in- ternamiento de enfermos religiosos y laicos además de médicos residentes. En América el primer hospital universitario fue fundado en los Estados Uni- dos en 1765 por la Universidad de Pensilvania, seguido del King’s College de Nueva York en 1768, la Universidad de Harvard en 1783, Darmouth Col- lege en 1798 y la Universidad de Yale en 1810 (3). Para finales del siglo XIX la educación médica ya se había traslado de las aulas universitarias a los pabellones hospitalarios con los pacientes. En México, la enseñanza clínica se remonta a finales del siglo XIX con la creación del Hospital General de México que buscaba cubrir las necesi- dades de atención médica y convertirse en una institución modelo de en- señanza (4). En junio de 1905 en el Diario Oficial de la Nación se estableció la importancia del Hospital General de México como Hospital Universitario. Todas las especialidades médicas en México fueron fundadas dentro de los pabellones del Hospital General y posteriormente se fueron expandiendo por toda la nación, incluso estableciendo Institutos Nacionales de Salud destinados a la atención, educación e investigación. Los hospitales universitarios tienen reputación de concentrar la atención altamente especializada para tratar enfermedades raras y pacientes grave- mente enfermos. En Estados Unidos, los hospitales universitarios pert- enecen al Council of Teaching Hospitals (COTH) de la Asociación Ameri- cana de Colegios de Medicina, ofrecen una relación de internos y residentes 3

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR a camas de 0.1 a 0.27 y están afiliados a una facultad de medicina (5). La calidad de atención en un hospital universitario tiende a ser mejor que en hospitales no universitarios, con menor riesgo de mortalidad y mejores desenlaces clínicos para los pacientes, ventajas que se replican sin impor- tar el lugar, población o complejidad de las enfermedades (6). El hospital universitario tiende a contar con mayor porcentaje de médicos certificados, enfermeras especializadas y tecnología de última generación, factores que brindan mayor confianza para los pacientes. En la actualidad, la medicina basada en evidencia es considerada como el non plus ultra, rezagando a un plano secundario la propia experiencia de los maestros, no por demeritarla, sino por el fundamento basado en el método científico para la toma de decisiones en la práctica clínica. Son los hospitales universitarios los lugares que suelen contar con todas las herra- mientas técnicas y de personal de salud para el desarrollo de protocolos de investigación que generarán conocimiento científico de calidad. Un estudio reportó en 2014 que el 86% de los artículos originales publicados de 2000 a 2009 en Dinamarca correspondieron a médicos afiliados a hospitales univer- sitarios, mismos que tuvieron mayor probabilidad de ser citados (7). A pesar de que la mayoría de las publicaciones fueron de hospitales no universi- tarios (regionales), la calidad de las publicaciones fue mayor en hospitales universitarios. Como ejemplo reciente de este último punto tenemos que en el año 2008 se analizó el patrón de publicación e impacto de los trabajos de mejor calidad presentados de 1998 a 2006 en la Asociación Mexicana de Gastroenter- ología (AMG) donde el 54.8% fueron publicados antes de un año en revistas con gran factor de impacto, incluyendo dos trabajos con más de 10 citas (8). El 97% de los trabajos premiados (34 de 35 trabajos) correspondieron a hospitales universitarios, incluyendo al Hospital Médica Sur con 2 premios y una publicación. En el año 1997 se creó el DOI (Digital Object Identifier) por iniciativa de la American Association of Publishers (AAP) con el objetivo de identificar “objetos” digitales y poder ser accedidos y trazados incluso tras el cambio de propietario o sitio en la web (9). Un año antes se creó PubMed, la base de datos electrónica de la Biblioteca Nacional de Medicina de Estados Uni- dos que actualmente cuenta con más de 33 millones de citas de literatura biomédica .(10) Estas dos herramientas en su conjunto son indispensables para la búsqueda, acceso y divulgación de artículos científicos alrededor del mundo. Desde el inicio de la pandemia COVID-19 en marzo de 2020, una gran can- tidad de artículos científicos relacionados con esta crisis de salud se public- aron y han sido disponibles a través del acceso libre digital .(11) Los hospital- es universitarios contribuyeron tanto a la atención de estos pacientes como la divulgación de las características clínicas de la enfermedad, su evolu- ción, tratamiento y desenlaces. Actualmente hay más de 225 mil artículos médicos disponibles en PubMed y la cifra continuará en aumento, ya que la enseñanza, la atención clínica y la generación de conocimiento científico siempre se mantendrán entrelazados en el rubro de la salud. Entre las páginas de este libro encontraremos los artículos publicados por investigadores pertenecientes a Médica Sur disponibles en PubMed desde el año 1990, correspondiendo la autoría del primero al Dr. Misael Uribe Es- quivel, Gastroenterólogo y Hepatólogo fundador del Hospital Médica Sur y actual Presidente Ejecutivo, así como el último artículo disponible al 14 de marzo del 2022 con la participación del Dr. Luis Soto Ramírez, Infectólogo y 4

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR actual Jefe de la Unidad de Vigilancia Epidemiológica Hospitalaria (UVEH) del Hospital Médica Sur en relación con la vacuna Patria contra COVID-19, un proyecto conjunto del Gobierno de México a través del Consejo Nacional de Ciencia y Tecnología (CONACYT) y los Laboratorios Avimex®. Más allá del valor histórico que tiene el recopilar y divulgar la labor científica del personal y de los socios de Médica Sur, el ejercicio de compilar en un libro la presencia del hospital en el ámbito científico tanto nacional como internacional nos muestra nuestros orígenes, nuestra evolución, elogia nuestros aciertos y nos muestra nuestro potencial en áreas aún poco explo- radas direccionándonos con nuevo ahínco hacia el futuro, pero por encima de todo plasma el arduo trabajo que por años el hospital ha realizado para la ciencia médica, la educación y la atención clínica en México. REFERENCIAS 1. Wonner E, Tschernig T, Pabst R. The Hippocratic Oath and the physi- cian’s pledge and their potential role early in medical education. Ann Anat. 2021;238:151780. 2. de Micheli A. Historia y filosofía de la medicina. En torno a la evolución de los hospitales. Gac Med Mex. 2005;141(1):57–62. 3. Burbridge CE. The Historical Background of the Teaching Hospital in the United States. J Natl Med Assoc. 1957;49(3):176–9. 4. Becerra Palars C, Cedillo Jiménez I, Garrido Galindo C, Fajardo Dolci G, de Anda Becerril E. El inicio de la enseñanza clínica en el Hospital General de México (1900-1909). Rev Med Hosp Gen (Mex). 1999;62(2):144–6. 5. Ayanian JZ, Weissman JS. Teaching Hospitals and Quality of Care: A Review of the Literature. Milbank Q. 2002;80(3):569–93. 6. Kupersmith J. Quality of care in teaching hospitals: A literature review. Acad Med. 2005;80(5):458–66. 7. Fedder J, Nielsen GL, Petersen LJ, Rasmussen C, Lauszus FF, Frost L, et al. A substantial number of scientific publications originate from non-university hospitals. Dan Med Bull. 2011;58(11). 8. Chávez-Tapia NC, Téllez-Avila FI, Hernández-Calleros J, López-Arce G, Franco-Guzmán A, Uribe M. Análisis de lso premios a la investi- gación en Gastroenterología. Experiencia en México. Med (Buenos Aires). 2008;68(2):135–8. 9. Morgan C. The DOI (Digital Object Identifier) [Internet]. UKSG. 1997 [cited 2022 Mar 18]. Available from: https://www.uksg.org/serials/doi 10. Canese K. PubMed Celebrates its 10th Anniversary! NLM Tech Bull. 2006;325:e5. 11. Škorić L, Glasnović A, Petrak J. A publishing pandemic during the COVID-19 pandemic: How challenging can it become? Croat Med J. 2020;61(2):79–81. 5

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RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR 1990 TÍTULO: [Electromagnetic shock wave lithotripsy plus bile acids for the treatment of gallblader stones: results and perspectives from the first 57 pa- PMID: 19256139 tients] AUTORES: Uribe M, Sánchez JM, Tielve JM, Dávila B, Gurza L, Bosques F, Kettenhofen W, Sánchez C, Castorena G. SUMMARY: Fifty seven patients were selected from 620 cases with gall- stones to be treated with an electromagnetic shock wave generator (Litho- star Plus). The machine has an overhead module with an electromagnetic generator able to produce 150-150 bar of pressure in the center of the focal zone (2 x 8 cms.) An in line ultrasound probe permits in vivo view of stone localization and fragmentations. The wide aperture of the device permits to treat patients with little pain in ambulatory basis. The mean age of the patients was 50 +/- 14 years, 57 were female and 20 were male. Stones were single in 35 cases and were multiple (2-4 gallstones) in the rest. The patients received a mean of 2620 +/- 371 shock waves. Intravenous anal- gesia (Fentanyl 87 +/- 40 ug p/session) was required in 26 cases. In 58.5% of the cases, fragmentation produced gallstone-rests of < 0.5 cm. Larger fragments (> 0.5 cm), were observed after an initial shock wave session in 33%. These patients underwent additional treatments sessions. Hence patients received 1.8 +/- 0.8 sessions. Minor fragmentation or no fragmen- tation after the first session was observed in the 14.5%. Mild biliary pain appeared in 17 patients and acute biliary colic in 2, one of these underwent emergency cholecystectomy. Overall gallstone disappearance after one year after lithotripsy, plus bile acid therapy (10-12 mg Kg day) was 72%. Patients with single gallstones were free of stones of fragments in 92% of the cases, after the same period of follow up. CITA: Rev Invest Clin. 1990 Jul;42 Suppl:71-4 PMID: 19256140 TÍTULO: [Extracorporeal shock waves lithotripsy during acute obstruction of the cystic duct] AUTORES: Sánchez JM, Castorena G, Uribe M. SUMMARY: Obstruction of the cystic duct after Biliary Shock Waves Lith- otripsy in an uncommon complication. It occurs when a small fragment is hemming in the neck of the gallbladder. Usually, cholecystectomy is the in- dicated treatment, we challenged this concept and attempted early ESWL to treat this complication. In our clinic, 150 patients were treated with a Lithostar-Plus device between March 1, 1989 to April 30, 1990. Of these, 12 presented acute uncontrolled biliary colic, 28 presented mild abdominal pain and the rest, remained pain free. Of the 12, one presented biliary obstruc- tion and cholecystectomy was performed in other hospital; one refused to be retreated and other presented sonographic gallbladder thickness and hence underwent surgery. Nine patients were re-treated and in all, fragments nest- ed in the gallbladder neck were successfully pulverised and obstruction cleared. To date all patients are free of stones. In summary, we propose ear- ly re-treatment with ESWL as a non-surgical alternative approach for treating this complication. CITA: Rev Invest Clin. 1990 Jul;42 Suppl:75-7 7

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 19256141 TÍTULO: [Focusing and targeting gallstones during extracorporeal shock waves lithotripsy] 1991 AUTORES: Sánchez JM, Sánchez C, Uribe M. SUMMARY: The gallbladder lies at the junction of the medial segment of the left and right hepatic lobes. Besides the anatomic location, other factors may interfere with an ideal targeting of gallstones during extracorporeal shock waves treatment. Obesity, malnourishment, the respiratory cycle, the pres- ence of intestinal gas, and colonic content may interfere with an adequate focalization. The use of a multipurpose device able to couple with the ante- rior abdominal wall like the Lithostar Plus permits to perform the procedure with the patient in supine, oblique or intercostal position. Varying the position permits to avoid interferences due to intestinal gas or intestinal content. The movements of the patients which produce a missing image can be easily refocussed. Technical ability, experience and a good machine permits a suc- cessful rate of gallstone fragmentation. CITA: Rev Invest Clin. 1990 Jul;42 Suppl:78-80 PMID: 1822011 TÍTULO: [Fragmentation of single biliary calculi with an electromagnetic gen- erator] 1994 AUTORES: Manuel Sánchez J, Méndez-Sánchez N, Bosques F, Gurza L, Dávila B, Guerrero J, Aguilar Ramírez A, Uribe M. SUMMARY: Extracorporeal shock wave lithotripsy is a non surgical alterna- tive for the treatment of cholelitiasis. At present, there are three main types of shock waves generators, one of them an electromagnetic device is (litho- star plus). The aim of this work is inform results obtained using Lithostar plus machine for the treatment of patients with a single gallstone. From total of 722 patients, 98 filled criteria for lithotripsy treatment; 63 patients had a single gallstone, with a mean age of 48.83 +/- 13.89 22 were males and 41 females. Patients were divided in 5 groups in base of the number of extra- corporeal shock waves used, all of them had similar a gallstones of similar size. 32 patients (50.8%) showed total fragmentation with only one session. According with the results obtained, we can conclude that using lithostar plus we can get total fragmentation in one session in 50.8% of patients with a single gallstone. CITA: Rev Gastroenterol Mex. Jul-Sep 1991;56(3):159-63 PMID: 7959154 TÍTULO: [An analysis of bone mass and remodeling in women with pharma- cological inhibition of ovarian function. The response to nasal calcitonin] AUTORES: Bori Segura G, Tamayo y Orozco JA, Onega Rosales Mdel C, Valero Origel A. SUMMARY: Pharmacological inhibition of ovarian function (PIOF) in young women is associated with hypoestrogenism and very low estrogen levels. 8

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR 1995 These alterations can trigger osteopenia, either by delayed peak bone mass or by active bone destruction, and therefore, an increased risk of osteoporo- PMID: 8948907 sis at later years. Twenty-one women (mean age: 32 years) with diagnosis of endometriosis, who were submitted to PIOF with leuprolide acetate, were 1996 prospectively studied. As a result of treatment for bone resorption with na- sal spray salmon calcitonin, 200 UI/day, a decreased femoral and lumbar PMID: 8756189 bone mass density was identified in these women through densitometry. Re- garding bone remodelling biochemistry, changes were seen in urinary mark- ers suggesting bone destruction inhibition, while bone formation markers showed stimulation. Biochemical markers of bone turnover and bone mass measurements are useful during follow-up of young women with osteopenia. CITA: Ginecol Obstet Mex. 1994 Sep;62:274-8 TÍTULO: [Chronic end-stage kidney failure in Mexico] AUTORES: Hernández-Llamas G, Espinoza-Vázquez B, Exaire-Murad E, Bordes-Aznar J, Dib-Kuri A, Tamayo y Orozco JA. SUMMARY: Chronic renal failure is an expanding and complex problem in Mexico. This work analyzes its current situation and finds a clear imbalance between supply and demand for specialized services, that favors the latter. To explain said imbalance, it invokes four factors: the recent innovation in nephrology and parallel disciplines; educational deficit of medical schools; high costs of rehabilitation of the uremic patient, and the absence of specifi- cally designed mechanisms for financing the treatment of this disease. CITA: Gac Med Mex. Jul-Aug 1995;131(4):459-63 TÍTULO: [Cervical pregnancy. Report of a case. Diagnostic and therapeutic considerations] AUTORES: Carranza-Lira S, García-Luna A, Rojas-Herrera E, Mantilla-Mo- rales A. SUMMARY: A patient with cervical pregnancy is reported, in spite of the im- portant bleeding a radical management was not required. Clinical, ultrasono- graphical and histopathological criteria which are needed for diagnosis are reviewed. Also some management alternatives are discussed. CITA: Ginecol Obstet Mex. 1996 Jul;64:297-9 PMID: 9102764 TÍTULO: [Cholestasis in the geriatric patient] AUTORES: Méndez-Sánchez N, Guevara González L, Uribe M. SUMMARY: Review article CITA: Rev Gastroenterol Mex. Oct-Dec 1996;61(4 Suppl 2):S123-6 9

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR 1997 PMID: 9044456 TÍTULO: Changes in the quality of life of patients with end-stage renal disease treated with high-efficiency bicarbonate hemodialysis in Mexico AUTORES: De Icaza E, Arredondo A, Calderon C, Hernandez G. SUMMARY: In accordance with the epidemiological changes in Mexico, the results of this study are intended to contribute to the evaluation of the end- stage renal disease (ESRD) program of the health services in Mexico. We measured the quality of life of 21 ESRD patients before and after 6 months of exposure to treatment with high-efficiency hemodialysis with bicarbonate (HEHD/bicarbonate). We cross-sectionally assessed the Quality Adjusted Life Year (QALY) index and the biochemical status of the subject pool. The QALY score for patients undergoing HEHD/bicarbonate after 6 months was significantly higher than with the previous dialysis modality (0.95 and 0.74, respectively, p = 0.02). The marked similarities of the biochemical status variables indicated there was little or no effect in the improvement of the quality of life of patients. Dialysis modality likely exerts an important influ- ence on the quality of life of chronic dialysis patients; thus we believe HEHD/ bicarbonate does offer greater benefits than hemodialysis alone. Longitu- dinal studies are needed to better ascertain the effect of the case mix, the treatment approach, and the characteristics of the dialysis in relation to the improvement of the quality of life of ESRD patients. CITA: Ren Fail. 1997 Jan;19(1):99-110 DOI: 10.3109/08860229709026264 PMID: 9302896 TÍTULO: Vertebral fractures associated with osteoporosis: patient man- agement AUTORES: Tamayo-Orozco J, Arzac-Palumbo P, Peón-Vidales H, Mo- ta-Bolfeta R, Fuentes F. SUMMARY: With the growing interest in new treatments aimed at preventing bone loss and conserving bone mass, insufficient attention has been given to symptomatic treatment of patients with vertebral fractures. Patients of- ten believe that the pain and impaired mobility associated with these frac- tures are permanent and that little can be done to help. This is a serious misconception. Prompt intervention using a multidisciplinary approach can hasten recovery from pain; improve mobility, flexibility, and speed of move- ment; and restore independence. Individualized care is needed because clinical features and degree of physical disability vary widely. Asymptomatic patients with vertebral fractures require evaluation and a management plan aimed at maintaining bone mass, improving functional status of the affected region, and preventing pain and new fractures. For patients with acute or chronic pain, treatment of pain and functional limitations is the first prior- ity, followed by functional rehabilitation and preservation of bone mass. A multidisciplinary approach to long-term care is recommended and includes lifestyle re-education, physical therapy, physical fitness training, neurologic and orthopedic evaluation, and, for some patients, use of an orthosis. After 4-6 weeks, those patients for whom pain is persistent require detailed study to detect neurologic, myofascial, or orthopedic complications that can lead to chronic impairment of mobility. Vertebroplasty, surgery using different modal- 10

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR ities, new exercise programs, and lifestyle modifications, together with more potent and effective medications to improve bone quality, are options to be used in the individual patient. Well-designed studies are needed that specifi- cally examine the management of these patients, particularly in the areas of pain relief and functional rehabilitation. CITA: Am J Med. 1997 Aug 18;103(2A):44S-48S DOI: 10.1016/s0002-9343(97)90026-7 PMID: 9412968 TÍTULO: Cholesterolosis is not associated with high cholesterol levels in pa- tients with and without gallstone disease 1998 AUTORES: Méndez-Sánchez N, Tanimoto MA, Cobos E, Roldán-Valadez E, Uribe M. PMID: 9590402 SUMMARY: High levels of cholesterol have been associated with certain gallbladder disorders such as cholesterolosis and gallstone disease. Fur- thermore, obesity is considered the main risk factor for cholesterol gallstone disease. We investigated the incidence of cholesterolosis in patients with and patients without gallbladder stones (GS). We reviewed the clinical re- cords of patients with gallstone disease and other gallbladder disorders who had consecutive cholecystectomy during a 5-year period. We recorded de- mographic data, sex, age, serum cholesterol levels, and body mass index. The diagnosis of cholesterolosis was made macroscopically and microscop- ically. A total of 636 patients were included in this study: 446 with and 190 without GS. Cholesterolosis was more frequent in patients without GS (p < 0.01). However, hypercholesterolemia occurred more frequently in patients with GS (p < 0.001). Obese patients with GS had higher percentages of cho- lesterolosis and hypercholesterolemia than did eutrophic patients (p < 0.01 and p < 0.05, respectively). We suggest that cholesterolosis in the human gallbladder is not necessarily associated with gallstone disease and high plasma cholesterol levels. CITA: J Clin Gastroenterol. 1997 Oct;25(3):518-21 DOI: 10.1097/00004836-199710000-00007 TÍTULO: Risk factors for gallstone disease in Mexicans are similar to those found in Mexican-Americans AUTORES: Méndez-Sánchez N, Vega H, Uribe M, Guevara L, Ramos MH, Vargas-Vorackova F. SUMMARY: According to epidemiological studies, gallstone disease is a very common disease in Mexican-Americans and Mexicans. However, the major risk factors for cholelithiasis in Mexicans have not been identified. We designed a case-control study in a group of Mexican subjects with and without gallstone disease confirmed by ultrasound. These subjects were prospectively studied over a three-year period. Clinical and epidemiological data were collected by means of a questionnaire. A total of 1500 subjects were included in this study: 1000 with and 500 without gallstone disease. The major risk factor in both men and women was body mass index [odds ra- 11

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 9823700 tio (OR) 1.64 and 1.96, respectively; P < 0.008 and 0.001]. In addition, parity was an important factor in women (OR 2.17, P < 0.001), whereas age was associated with gallstone disease in men (OR 1.43, P < 0.001). We found that body mass index, parity, and age were the principal risk factors for gall- stone disease in this group of Mexican subjects. These results are similar to those found in Mexican-American populations. CITA: Dig Dis Sci. 1998 May;43(5):935-9 DOI: 10.1023/a:1018849911355 TÍTULO: [Cancer of the colon and pregnancy] AUTORES: Carranza-Lira S, Zavala-García C. SUMMARY: In a woman 31 year old, with a 21 week pregnancy, an ade- nocarcinoma was found in transverse colon, it was excised; she received chemotherapy. At week 33, a healthy female baby was obtained by cesarean section. The patient died four months after the diagnosis. Estrogen receptors in colon tumor were negative. CITA: Ginecol Obstet Mex. 1998 Nov;66:444-5 PMID: 9829367 TÍTULO: Beneficial effect of carbohydrate maldigestion induced by a disac- charidase inhibitor (AO-128) in the treatment of chronic portal-systemic en- cephalopathy. A double-blind, randomized, controlled trial AUTORES: Uribe M, Morán S, Poo JL, Méndez-Sánchez N, Guevara L, García-Ramos G. BACKGROUND: The most widely used treatment of portal-systemic en- cephalopathy (PSE) is the administration of oral, non-absorbable disac- charides. Theoretically, the inhibition of intestinal disaccharidases should induce malabsorption of disaccharides and increase delivery of undigested carbohydrates to the colon, thus stimulating the effects of lactulose and other non-absorbable disaccharides (that is, lactitol and lactose). AO-128 is an N-substituted derivative of valeolamine, an aminocyclitol that selectively inhibits intestinal disaccharidases. This study was performed to investigate whether AO-128 could be used as adjuvant therapy for the treatment of mild PSE in cirrhotic patients. METHODS: A double-blind, randomized, controlled trial was performed in 35 cirrhotic patients with PSE. Patients were given a 2-week treatment consist- ing of AO-128 (2 mg three times daily) or an identical placebo. The following features of PSE syndrome were assessed in a semiquantitative fashion be- fore and after I and 2 weeks of therapy: mental state, asterixis, number con- nection test (NCT), venous blood ammonia concentration, electroencephalo- gram (EEG), and overall PSE index (PSEI). More patients receiving AO-128 than patients receiving placebo showed >40% improvement in the PSEI (83% versus 35%; P < 0.05). The mean stool pH decreased from 5.8+/-0.3 to 5.5+/-0.3 (P < 0.004) after AO-128 treatment, whereas no changes were observed in the placebo group. The EEG and nitrogen balance did not show significant changes in any of the two groups. A significant improvement was seen in the NCT performance after AO-128 (from grade 2.0+/-1.04 to grade 1.25+/-0.87; P < 0.05). Seven patients treated with AO-128 developed diar- rhea, as compared with none in the placebo group (P < 0.05). 12

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR CONCLUSION: These results suggest that AO-128 may be useful in the treatment of PSE, although further studies are required to establish the ben- efit of AO-128 and determine adequate individual doses. CITA: Scand J Gastroenterol. 1998 Oct;33(10):1099-106 DOI: 10.1080/003655298750026822 1999 PMID: 10491043 TÍTULO: Frozen allogeneic human epidermal cultured sheets for the cure of complicated leg ulcers AUTORES: Bolívar-Flores YJ, Kuri-Harcuch W. BACKGROUND: Skin ulcers due to venous stasis or diabetes are common among the elderly and are difficult to treat. Repeated applications of cell- based products have been reported to result in cure or improvement of leg ulcers of small size in a fraction of patients. OBJECTIVE: To examine the effects of frozen human allogeneic epidermal cultures for the treatment of acute and chronic ulcers. METHODS: We treated a series of 10 consecutive patients with leg ulcers of different etiology and duration with frozen human allogeneic epidermal cultures stored frozen and thawed for 5-10 minutes at room temperature before application. Three patients had ulcers with exposed Achilles or ex- tensor tendon. The ulcers treated were as large as 160 cm2 in area and of up to 20-years' duration. After preliminary preparation of the wounds by de- bridement to remove necrotic tissue and application of silver sulfadiazine to control infection, thawed cultures were applied biweekly from 2 to 15 times depending on the size and complexity of the ulcer. RESULTS: All ulcers healed, including those with tendon exposure. After the first few applications, granulation tissue formed in the ulcer bed and on ex- posed tendons, and epidermal healing took place through proliferation and migration of cells from the margins of the wound. The time required for com- plete healing ranged from 1 to 31 weeks after the first application. CONCLUSION: The use of frozen human allogeneic epidermal cultures is a safe and effective treatment for venous or diabetic ulcers, even those with tendon exposure. It seems possible that any leg ulcer will be amenable to successful treatment by this method. CITA: Dermatol Surg. 1999 Aug;25(8):610-7 DOI: 10.1046/j.1524-4725.1999.99022.x PMID: 10582393 TÍTULO: [Changes in iron levels in non-anemic women 18-58 years of age] AUTORES: Baptista González HA, Rosenfeld MF, Peñuela Olaya MA, Sor- roza Martínez MA, Tello Nielsen J. 13

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 10634078 SUMMARY: The objective was to describe changes in serum ferritin (SF) in women residents in Mexico City. We evaluated prospectively, three groups 2000 of non-anemic, non-pregnant women (< 20, 21-40 y 40-58 years old). So- ciodemographic variables, hemoglobin (Hb) and erythrocyte index and SF PMID: 11444273 values were registered. We included 252 women in the study. There were no differences in Hb values (15.0, 14.6 and 14.7 g/dL) or erythrocyte index between the three groups of women. We found significative differences (p < 0.001) in mean values of (32 and 34 micrograms/L), for group 1 and 2, with group 3 (SF 54 micrograms/L). In global sample, we observed low SF store, a normal or higher in 76 cases (30.2%), 163 (64.6%) and 13 cases (5.2%), respectively. The women with SF lower than 20 micrograms/L were in pro- portion 0.54, 0.32 and 0.16. Elevated values in SF were found in a propor- tion 0.04, 0.18 and 0.13, for groups 1, 2 and 3, with significative differences (p < 0.001). We observed that non-anemic women in Mexico City, showed increase in SF concentrations beginning at 41 years of age, without any ma- jor variation in their erythocyte indexes. The prevalence in moderate-severe iron deficiency between 18 to 40 years of years, decreasing progressively. CITA: Ginecol Obstet Mex. 1999 Oct;67:467-72 TÍTULO: [The prevalence of hepatitis B and C in blood donors in a 3rd-level hospital of Mexico City] AUTORES: Méndez-Sánchez N, Baptista-González H, Sánchez-Gómez RH, Bordes-Aznar J, Uribe-Esquivel M. OBJECTIVE: To investigate the prevalence of the hepatitis C virus (HCV) and B virus (HBV) in blood donors attending Médica Sur Hospital. MATERIAL AND METHODS: A total of 9,099 blood donors were tested for hepatitis B and C viruses from 1994 to 1998. A questionnaire was used to collect data and HCV and HBV were detected in serum. We obtained per- centages and assessed statistical significance using the chi 2 test. RESULTS: The prevalence of HCV and HBV carriers was 0.47 and 0.11 per cent. The main risk factors were dental procedures (11.6% for HCV and 20%, for HBV), and unsafe sexual practices (20%) for HBV. Conclusions: These results indicate a low prevalence of HCV and HBV in- fection in this population. CITA: Salud Publica Mex. Nov-Dec 1999;41(6):475-8 TÍTULO: Circle hairs: a clinical curiosity AUTORES: Contreras-Ruiz J, Duran-McKinster C, Tamayo-Sanchez L, Orozco-Covarrubias L, Ruiz-Maldonado R. SUMMARY: A case of circle hairs is reported and the literature on the sub- ject reviewed. Differential diagnoses are discussed as well as some theories on the nature of circle hairs. CITA: J Eur Acad Dermatol Venereol. 2000 Nov;14(6):495-7 DOI: 10.1046/j.1468-3083.2000.00163.x 14

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR 2001 TÍTULO: Lack of association between Helicobacter sp colonization and gall- stone disease PMID: 11205649 AUTORES: Méndez-Sánchez N, Pichardo R, González J, Sánchez H, Moreno M, Barquera F, Estevez HO, Uribe M. SUMMARY: Recently, Helicobacter sp has been identified in resected gallbladder tissue and in collected bile from Chilean patients with chronic cholecystitis. Therefore, it an association between bile Helicobacter sp and gallbladder cancer has been proposed. Interestingly, both Helicobacter col- onization and gallstone disease (GD) happen very frequently in Chile. How- ever, whether there is an association between Helicobacter colonization and GD has not been completely studied. The aim of this study was to determine the incidence of Helicobacter in human gallbladder tissues with GD. The study included 95 Mexican patients undergoing cholecystectomy. Collect- ed gallbladder specimens were assessed to identify Helicobacter sp using histology, immunohistochemistry, and polymerase chain reaction (PCR) analysis using Helicobacter-specific 16-S ribosomal RNA primers. Of the 95 specimens examined in detail, all had stones as follows: 56 (59%) had chronic cholecystitis; 7 (7.4%), acute cholecystitis: 15 (16%), both chronic and acute cholecystitis, 10 (9.5%), cholesterolosis, and 7 (7.4%), lymphoid hyperplasia. Specimens were considered positive for Helicobacter when histology was positive. Only 1 of the 95 specimens was positive for Heli- cobacter by immunohistochemistry analysis; 1 of 32 cases, by PCR. These results suggest a low incidence of Helicobacter in the gallbladder epithelium of Mexican patients with GD. However, we can not discard the existence of uncommon Helicobacter sp in gallbladder epithelium and its association with gallstone pathogenesis. Additionally, this study suggests no apparent associ- ation between GD and Helicobacter colonization in a Mexican population. CITA: J Clin Gastroenterol. 2001 Feb;32(2):138-41 DOI: 10.1097/00004836-200102000-00009 PMID: 11490829 TÍTULO: Delayed gastric emptying in subjects with Gilbert's syndrome AUTORES: Méndez-Sánchez N, González V, Flores A, Martínez M, Graef A, Uribe M. BACKGROUND/AIMS: Recently, it has been proposed that decreased in- testinal motility in fasting-induced hyperbilirubinemic rats probably results in an increase in the enterohepatic cycling of unconjugated bilirubin. We inves- tigated the association among gastric emptying, intestinal transit time, and serum unconjugated levels in subjects with Gilbert's syndrome. METHODOLOGY: Ten subjects with Gilbert's syndrome were included in this study according to the following criteria: fasting hyperbilirubinemia; no hemo- lysis or gastrointestinal disorders and free of any medication. Five normal, healthy volunteers acted as controls. Gastric emptying and intestinal transit time were evaluated after overnight fasting by administration of a standard meal mixed with 1-2ci of 99Tc-labeled diethylene-triamine-pentacetic acid. Serum unconjugated bilirubin levels were determined by high-performance liquid chromatography. 15

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR RESULTS: The gastric emptying in Gilbert's syndrome subjects was 134.1 +/- 38.9 and 90.9 +/- 6.5 min in controls, P < 0.03. It was a tendency to have a shorter intestinal transit time in subjects with Gilbert's syndrome, 138.3 +/- 59.0, than in control subjects, 183.8 +/- 11.3 min. Serum unconjugated bilirubin levels (mg/dL) were 2.6 +/- 1.04 and 0.95 +/- 0.34, P < 0.01. CONCLUSIONS: Gastric emptying is delayed significantly in Gilbert's syn- drome, and intestinal transit time differences between Gilbert's syndrome subjects and controls were not significantly different. CITA: Hepatogastroenterology. Jul-Aug 2001;48(40):1183-5 PMID: 11533270 TÍTULO: Fish oil (n-3) polyunsaturated fatty acids beneficially affect biliary cholesterol nucleation time in obese women losing weight AUTORES: Méndez-Sánchez N, González V, Aguayo P, Sánchez JM, Tan- imoto MA, Elizondo J, Uribe M. SUMMARY: It has been reported that intake of (n-3) polyunsaturated fatty acids (PUFA) reduces the risk of coronary heart disease and decreases bil- iary cholesterol saturation in the bile of gallstone patients. We investigated the effect of n-3 PUFA on cholesterol saturation index (CSI) and nucleation time (NT) in obese subjects who were losing weight. This was a double-blind, placebo-controlled clinical trial. Obese women (n = 35) with a body mass index (BMI) > or = 30 kg/m(2), with no prior history of gallstones or cholecys- tectomy by ultrasound were first studied to ensure absence of stones or bil- iary sludge. The women were then assigned to a hypocaloric regimen [5.02 MJ (1200 kcal)/d] and to receive 1200 mg/d of ursodeoxycholic acid (UDCA), 11.3 g/d of (n-3) PUFA or a placebo for 6 wk. BMI, CSI and NT were recorded at baseline and at the end of the experimental period. BMI decreased 5.75 +/- 2.7%/mo (range, 1.5-12.42%/mo) during the experiment. The CSI did not change in any of the groups. Cholesterol NT decreased significantly in the UDCA and placebo groups, but not in the (n-3) PUFA group. None of the women had developed gallstones at 6 wk. These results suggest that (n-3) PUFA maintain the CSI and NT in obese women during rapid weight loss, which probably results in the prevention of cholesterol gallstone formation. CITA: J Nutr. 2001 Sep;131(9):2300-3 DOI: 10.1093/jn/131.9.2300 PMID: 11589719 TÍTULO: Zinc salts precipitate unconjugated bilirubin in vitro and inhibit en- terohepatic cycling of bilirubin in hamsters AUTORES: Méndez-Sánchez N, Roldán-Valadez E, Flores MA, Cárdenas- -Vázquez R, Uribe M. BACKGROUND: Microscopic colitis is responsible for a proportion of diffi- cult diagnosis cases with chronic diarrhea. Diagnosis is clinically suspected when chemical and macroscopic examination result negative and is made only by histopathologic findings. OBJECTIVE: To describe clinical, biochemical, colonoscopic, and histologic features and the treatment response of four cases with microscopic colitis. 16

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR METHODS: We inform on the findings in four females patients presenting with chronic watery diarrhea with normal biochemical and colonoscopic tests. RESULTS: In these cases, diagnoses mode were lymphocytic colitis two and collagenous colitis two. The long term duration of watery diarrhea was 5 months. The average number of depositions were 10 in 24 h. Diagnosis was made after microscopic examination of the colonic mucosa in the absence of endoscopic abnormalities and normal chemistries. All patients had a satis- factory response to treatment. CONCLUSIONS: The diagnosis of microscopic colitis is made by histopa- thology findings. The therapeutic response is generally satisfactory. CITA: Eur J Clin Invest. 2001 Sep;31(9):773-80 DOI: 10.1046/j.1365-2362.2001.00879.x 2002 PMID: 12066432 TÍTULO: [Microscopic colitis] AUTORES: Lizardi-Cervera J, Morán-Villota S, Hinojo-Rivas E, Reynoso- -Mendoza R, Correa-Rovelo JM, Pichardo-Bahena R, Uribe-Esquivel M. BACKGROUND: Microscopic colitis is responsible for a proportion of diffi- cult diagnosis cases with chronic diarrhea. Diagnosis is clinically suspected when chemical and macroscopic examination result negative and is made only by histopathologic findings. OBJECTIVE: To describe clinical, biochemical, colonoscopic, and histologic features and the treatment response of four cases with microscopic colitis. METHODS: We inform on the findings in four females patients presenting with chronic watery diarrhea with normal biochemical and colonoscopic tests. RESULTS: In these cases, diagnoses mode were lymphocytic colitis two and collagenous colitis two. The long term duration of watery diarrhea was 5 months. The average number of depositions were 10 in 24 h. Diagnosis was made after microscopic examination of the colonic mucosa in the absence of endoscopic abnormalities and normal chemistries. All patients had a satis- factory response to treatment. CONCLUSIONS: The diagnosis of microscopic colitis is made by histopa- thology findings. The therapeutic response is generally satisfactory. CITA: Rev Gastroenterol Mex. Jan-Mar 2002;67(1):47-52 PMID: 12163661 TÍTULO: Plasma leptin and the cholesterol saturation of bile are correlated in obese women after weight loss AUTORES: Méndez-Sánchez N, González V, King-Martínez AC, Sánchez H, Uribe M. SUMMARY: Increased cholesterol secretion is a major alteration of biliary function in obese subjects Leptin is a regulator of food intake and is in- 17

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR creased in plasma of subjects with low energy expenditure and high adipos- ity. We investigated the relationship between leptin and the cholesterol sat- uration of bile in obese women before and after weight reduction by energy restriction (5.02 MJ/d). We studied women (n = 14) with a body mass index (BMI) > or = 30 kg/m(2) who were 35.4 +/- 2.3 y old and who did not have a history of gallstones. They were studied by ultrasound to ensure absence of stones or sludge. BMI, gallbladder bile composition, plasma leptin, serum lipids and lipoproteins cholesterol levels were recorded at baseline and after 6 wk of weight reduction. There were decreases in BMI (33.9 +/- 3.1 to 31.1 +/- 3.6 kg/m(2), P < 0.0001) and leptin levels (16.7 +/- 9.7 to 10.0 +/- 6.7 mi- cro mol/L, P < 0.05) during weight loss. After the experimental period, there were positive correlations between plasma leptin levels and BMI (r = 0.71, P < 0.004); leptin levels and the cholesterol saturation index (CSI) (r = 0.53, P < 0.05); the CSI and LDL cholesterol (r = 0.73, P < 0.003); and nega- tive correlations between leptin levels and HDL cholesterol (r = -0.54, P < 0.05) and LDL cholesterol (r = -0.57, P < 0.03). We have shown relationships among HDL cholesterol, CSI and leptin. This could be useful in understand- ing the pathophysiology of cholesterol gallstone formation in obese people. CITA: J Nutr. 2002 Aug;132(8):2195-8 DOI: 10.1093/jn/132.8.2195 PMID: 12198690 TÍTULO: Image of the month. Pyogenic liver abscess complicated by bron- chial fistula AUTORES: Méndez-Sánchez N, Reyes MT, Corona R, Uribe M. SUMMARY: Case report CITA: Gastroenterology. 2002 Sep;123(3):666, 957 DOI: 10.1053/gast.2002.35761 PMID: 12394436 TÍTULO: Stapled rectal mucosectomy vs. closed hemorrhoidectomy: a ran- domized, clinical trial AUTORES: Correa-Rovelo JM, Tellez O, Obregón L, Miranda-Gomez A, Moran S. INTRODUCTION: We compared the safety and clinical outcome between stapled rectal mucosectomy and closed hemorrhoidectomy for the surgical treatment of noncomplicated hemorrhoidal disease. METHODS: Eighty-four patients with Grade III and IV hemorrhoidal disease were randomly assigned to two groups: 1) stapled rectal mucosectomy group (n = 42) and 2) closed hemorrhoidectomy group (n = 42). Postoper- ative pain, analgesic use, symptoms, disability, early and late complications, and patient satisfaction were evaluated, among others. Follow-up was six months. RESULTS: Eighty-four patients, averaging 45 +/- 9 years of age, underwent surgery. Two were lost to follow-up. Length of surgery and disability, postop- erative pain, and use of analgesics were significantly less for patients in the stapled rectal mucosectomy group. In the closed hemorrhoidectomy group 18

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR early complications were more frequent but not statistically significant, and there were no statistically significant differences regarding the frequency of late complications. No serious complications were reported in either group. Closed hemorrhoidectomy proved to be superior for bleeding control (95.1 percent closed hemorrhoidectomy 80.5 percent stapled rectal mucosectomy; P= 0.04). Patient satisfaction was similar in the two groups, but stapled rec- tal mucosectomy patients were more willing to undergo the same procedure (P = 0.02). CONCLUSION: Both stapled rectal mucosectomy and closed hemorrhoidec- tomy are safe procedures. Closed hemorrhoidectomy was superior for bleed- ing control in Grade III and IV hemorrhoidal disease, but more painful and disabling than stapled rectal mucosectomy. CITA: Dis Colon Rectum. 2002 Oct;45(10):1367-74 DOI: 10.1007/s10350-004-6426-3. PMID: 12418301 TÍTULO: [Vasopressin: uses in cardiovascular practice] AUTORES: González Chon O, García López SM. PMID: 12685225 SUMMARY: Vasopressin is secreted by the neurohypophysis influenced PMID: 12712845 by many variables; among them the most important and known is the os- motic pressure (osmotic regulation) of body fluid. Other factors that modi- fy this hormone's secretion are changes in blood volume and blood pres- sure, which contribute significantly to hemodynamic recovery. Vasopressin receptors are located in different sites, and their stimulation generate also generates different physiological responses. The receptors are of two types, V1 and V2. The usefulness of exogenous vasopressin has been proven in many clinical situations, refractory cardiac arrest, septic shock, vasodilator shock, postcardiotomy shock, and vasoplegic shock, with promising results. At present, enough scientific support exists for the use of this antidiuretic hormone (vasopressin) in clinical practice. CITA: Arch Cardiol Mex. Jul-Sep 2002;72(3):249-60 TÍTULO: [National consensus on hepatitis C. Conclusions] AUTORES: Méndez-Sánchez N, Uribe M. SUMMARY: Review article CITA: Rev Invest Clin. Nov-Dec 2002;54(6):559-68 TÍTULO: [Epidemiology of hepatitis C] AUTORES: Méndez-Sánchez N. SUMMARY: Multiple studies have been made to determine the occurrence of infection with HCV after sexual contact and from the infected mothers to their newborn children. As far as sexual contact is concerned, it's clear that this route of transmission is possible. The most definite results show the homogeneity of HCV RNA in 99% of monogamous couples without previous use of intravenous drugs. As far as mother-newborn transmission is con- 19

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 12712851 cerned, it has been proven that transmission is related to the mother's viral PMID: 12712853 load. In those women with HCV RNA levels above 10(6) copies/ml, transmis- sion was as high as 36%. Moreover, some reported studies with irrefutable data show that perinatal transmission is higher in mothers co-infected with human immunodeficiency virus. The precise transmission mechanism in both situations is still unknown. CITA: Rev Gastroenterol Mex. 2002 Oct;67 Suppl 2:S13-6 TÍTULO: [Relation between hepatocarcinoma and hepatitis C virus infec- tion] AUTORES: Pichardo-Bahena R, Méndez-Sánchez N. SUMMARY: The incidence of hepatocarcinoma (HCC) has increased in in- dustralized countries. Its relation with hepatitis C virus (HCV) has already been established. The mechanisms by which HCV promotes HCC devel- opment are poorly understood. The continuous necrotic and inflammatory effect with subsequent liberation of various cytoquines and modifications in hepatocyte genome have been proposed. Chronic infection with HCV leads to chronic liver disease and cirrhosis which is described as the main precur- sory lesion to HCC. The assessment methods for patients with chronic liver diseases allow those patients with high risk for HCC to be identified and the process to identify this tumor at an early stage to be initiated. CITA: Rev Gastroenterol Mex. 2002 Oct;67 Suppl 2:S36-41 TÍTULO: [Treatment of patients with recurrence or who do not respond to the first treatment against hepatitis C] AUTORES: Poo JL. SUMMARY: The current criteria to confirm the absence of therapeutic re- sponse to HCV is based on the viral findings. Lack of response is defined as the failure to achieve a negative serological response to the virus in pe- ripheral blood (serum or plasma) after 12 weeks of treatment with interferon alpha (2a or 2b), or 24 weeks of treatment with IFN and ribavirin. Up to 60% of patients treated with standard IFN alpha and ribavirin are considered non-responders. According to viral genotype, figures are still worse in the group with genotype 1. Recently, the use of pegylated interferon allowed the reduction of the number of non-responding patients. The investigators propose different approaches in the search for better therapeutic strategies. The most effective of them all are the addition of ribavirin to the therapeu- tic scheme and the use of pegylated interferon which greatly increased the number of responders. Nevertheless, there are still many patients who are resistant to therapy. These are the proposed therapeutic alternatives for non-respondent patients: 1. Another tretment cycle with standard IFN and ribavirin (low probability) 2. Another treatment cycle with pegylated IFN and ribavirin. 3. Another treatment cycle with IFN, ribavirin and amantadine. 4. Another treatment cycle with IFN, ribavirin and timosine. 5. Other antiviral agents. It's important to clarify that \"real non-responders\" are those patients who remain positive in the viral load tests after 12-24 months of treatment. On the other hand, patients who \"escape from treatment\" or those with \"re- currence\" are not real non-responders, compared to those who are negative after 12-24 weeks of treatment. CITA: Rev Gastroenterol Mex. 2002 Oct;67 Suppl 2:S45-8 20

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 12712860 TÍTULO: [Hepatitis C virus infection in patients with hemophilia] AUTORES: Baptista González HA. SUMMARY: After the introduction of second generation ELISA and confir- matory tests clinically available, it was possible to determine that prevalence of infection with HCV was 98% among hemophiliacs exposed to factor VIII concentrates that weren't submitted to viral inactivation. Liver failure is 4.2 times more probable among patients also infected with HIV. The hepatocel- lular carcinoma studies show similar findings. They report a rate of 1.4 for every 1,000 hemophiliacs, and almost all patients have antibodies for hepati- tis C virus. The studies with hemophiliacs exposed to unsafe blood products for HCV showed a significant increase in mortality from different liver dis- eases, as compared to control subjects. Mortality rate shows an important increase in the hemophiliacs also infected with human immunodeficiency virus. Combination therapy (ribavirin and interferon) doesn't seem to make a difference in the response rate as compared to patients without hemophilia. In spite of the best efforts to improve the safety of factor VIII concentrates, it has been impossible to eliminate the risk of transmission of other infective agents. That's why it seems that recombinant technology will be the answer in obtaining the concentrates. CITA: Rev Gastroenterol Mex. 2002 Oct;67 Suppl 2:S75-9 PMID: 12712862 TÍTULO: [Hepatitis C and addictions] AUTORES: Sánchez Avila JF. SUMMARY: Currently, it has been suggested that hepatitis C virus is the major cause of chronic liver disease. In Western countries, approximately 60% of the cases has been related with intravenous drugs. Also it has been suggested an interaction among alcohol and hepatitis C virus that in turn might induce an additive or synergic effects in causing liver injury. This re- view analyzes the effect of intravenous drugs and alcohol in the course of chronic hepatitis C. CITA: Rev Gastroenterol Mex. 2002 Oct;67 Suppl 2:S84-7 PMID: 15114295 TÍTULO: Zinc sulfate inhibits the enterohepatic cycling of unconjugated bili- PMID: 15114296 rubin in subjects with Gilbert's syndrome AUTORES: Méndez-Sánchez N, Martínez M, González V, Roldán-Vala- dez E, Flores MA, Uribe M. SUMMARY: Case report CITA: Ann Hepatol. Jan-Mar 2002;1(1):40-3 TÍTULO: Amebic liver abscess and liver cirrhosis AUTORES: Guevara-González L, Méndez-Sánchez N. SUMMARY: Case report CITA: Ann Hepatol. Jan-Mar 2002;1(1):44 21

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 15115973 TÍTULO: Hepatic apolipoprotein A-I gene expression in patients with choles- terol gallstones treated with ursodeoxycholic acid PMID: 15115974 PMID: 15115975 AUTORES: Méndez-Sánchez N, Panduro A, Murguía D, Rincón AR, Uribe M. OBJECTIVE: It has been suggested that apo A-I can inhibit cholesterol crystal nucleation in vitro, and ursodeoxycholic acid (UDCA) is a safe and effective treatment for selected patients with cholesterol gallstones the aim of this study was to investigate the effect of UDCA on the steady-state levels (SSL) of apo A-I mRNA in the liver, as well as serum apo A-I, in patients with cholesterol gallstones. DESIGN: Twenty Mexican patients with symptomatic radiolucent gallstones were randomized and assigned in a double blind fashion to groups that were administered either UDCA (4 mg/kg per day) or placebo for 10 to 15 days be- fore cholecystectomy. Apo A- I mRNA levels in liver and gallbladder tissues were determined by northern blot and serum levels of apo A- I by turbidimet- ric method. METHODS: Apo A- I mRNA levels were higher in nine of the 10 patients who received UDCA and in comparison to those to the placebo group. In the gall- bladder apo A- I mRNA levels were undetected. Serum levels (mg/dL) of apo A- I were similar in both UDCA and placebo groups after treatment (111.7 +/- 29.8 vs 115.6 +/- 25.4). CONCLUSIONS: The results of this study shown that apo A- I mRNA gene express at the mRNA level in the liver but not in the gallbladder of patients with cholesterol gallstones treated with UDCA. CITA: Ann Hepatol. Apr-Jun 2002;1(2):85-9 DOI: 10.1016/S1665-2681(19)32180-5 TÍTULO: Amebic liver abscess open to the inferior vena cava AUTORES: Guevara-González L, Méndez-Sánchez N. SUMMARY: Case report CITA: Ann Hepatol. Apr-Jun 2002;1(2):90 DOI: 10.1016/S1665-2681(19)32181-7 TÍTULO: Epithelioid granulomas in a patient with hepatitis C virus AUTORES: Pichardo-Bahena R, Méndez-Sánchez N. SUMMARY: Hepatitis C virus infection causes an epidemic disease. The morphologic aspects of hepatitis C infection (HCV) are well established with regards to necroinflammatory processes and consequences like fibrosis, cir- rhosis, and related neoplasms. However, the presence of epithelioid gran- ulomas has not been well described for this infection. We report a patient with HCV and granulomas without any other co-infection or history of drug abuse. CITA: Ann Hepatol. Apr-Jun 2002;1(2):91-3 DOI: 10.1016/S1665-2681(19)32182-9 22

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 15280807 TÍTULO: Caroli's disease and choledochal cyst AUTORES: Hérnandez-Ortiz J, Corona R, Méndez-Sánchez N. PMID: 15280808 SUMMARY: Case report 2003 CITA: Ann Hepatol. Oct-Dec 2002;1(4):196 DOI: 10.1016/S1665-2681(19)32166-0 PMID: 12560921 TÍTULO: Caroli's disease and choledochal cyst AUTORES: Hérnandez-Ortiz J, Corona R, Méndez-Sánchez N. SUMMARY: Case report CITA: Ann Hepatol. Oct-Dec 2002;1(4):196 DOI: 10.1016/S1665-2681(19)32166-0 TÍTULO: Diagnostic value of the copper/zinc ratio in hepatocellular carcino- ma: a case control study AUTORES: Poo JL, Rosas-Romero R, Montemayor AC, Isoard F, Uribe M. BACKGROUND: The aim of this study was to assess the accuracy of the copper/zinc ratio in the evaluation of a group of patients with hepatocellular carcinoma (HCC). METHODS: A total of 105 patients were studied and separated into three groups: group I ( n = 40), patients with HCC, group II ( n = 25), patients with liver cirrhosis, and group III ( n = 40), patients with benign digestive disease. Serum levels of copper and zinc were measured by atomic absorption spec- trophotometry. RESULTS: The serum levels of copper microg/dl) in patients with HCC (97.4 +/- 27.2; P < 0.05) were significantly higher than those in patients with liver cirrhosis (73.7 +/- 17.5) or benign digestive disease (77.1 +/- 20.8), and the serum levels of zinc microg/dl) were significantly lower (71.6 +/- 30.5; P < 0.05) than those in patients with benign digestive disease (81.7 +/- 17.7 mi- crog/dl) and were similar to those in cirrhotic patients (68.5 +/- 17.1). The Cu/Zn ratio was also significantly higher in patients with HCC (1.52 +/- 0.64; P < 0.05) than in patients with liver cirrhosis (1.06 +/- 0.2) or patients with benign digestive disease (0.95 +/- 0.39). Considering a cutoff value of 1.15, the sensitivity of the Cu/Zn ratio was 87.5%, with a specificity of 86.1%, a positive predictive value of 79.5%, and a negative predictive value of 91.8%. CONCLUSIONS: The Cu/Zn ratio was found to be significantly higher in pa- tients with HCC compared with that in age and sex-matched controls, with a sensitivity of 87.5%; this ratio might be useful in the evaluation of suspected hepatocellular malignancy. CITA: J Gastroenterol. 2003;38(1):45-51 DOI: 10.1007/s005350300005 23

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 12700135 TÍTULO: The role of dietary fats in the pathogenesis of gallstones AUTORES: Méndez-Sánchez N, Chavez-Tapia NC, Uribe M. SUMMARY: Gallstone disease is exceptionally common, occurring espe- cially in Western populations, with cholesterol gallstones predominating. Currently, it is believed that one of the essential factors in the pathogenesis of cholesterol gallstones is a physical-chemical event that results primarily from alterations in the lipid composition of gallbladder bile. Cholesterol su- persaturation is due principally to excessive secretion of cholesterol into the bile. Several biochemical defects, as well as diet, might cause hypersecre- tion of cholesterol. The precise effects of diet on cholesterol supersaturation of bile have not been clearly established, although epidemiological, clinical, and animal studies indicate that diet plays an important role in cholesterol gallstone formation. This review summarizes current information on the role of dietary fat in the modulation of cholesterol gallstone formation. CITA: Front Biosci. 2003 May 1;8:e420-7. DOI: 10.2741/1110 PMID: 12717670 TÍTULO: [Colloid cyst of the third ventricle: case description and survey of the literature] AUTORES: Roldán-Valadez E, Hernández-Martínez P, Elizalde-Acosta I, Osorio-Peralta S. INTRODUCTION: Colloid cysts are intracranial lesions with an estimated incidence of three individuals per million people per year. They are benign tumours in the anterosuperior portion of the third ventricle. The normal flow of cerebrospinal fluid may be interrupted by a large cyst that obstructs the foramen of Monro. The associated signs and symptoms cover a wide range of features, from non specific headaches to intracranial hypertension data; some colloid cysts occur at the acute onset of hydrocephalus and can lead to a sudden death. CASE REPORT: We present the case of a patient with a colloid cyst in the anterior roof of the third ventricle, with the presence of a dysfunctional ventri- culo peritoneal bypass valve, which had been introduced three years earlier. Both events contributed to the development of a hydrocephalus with clinical manifestations of intracranial hypertension. The images obtained by magnet- ic resonance (MR) revealed the presence of a hyperintense mass of variable density in the roof of the third ventricle and in its rostral face; the image was hyperintense in T1 and isointense in T2. The patient was submitted to an en- doscopic cisternoventriculostomy to allow the surgical drainage of the colloid cyst, and management was continued in the outpatients department of the Neurosurgery Service. CONCLUSIONS: In this paper we discuss the main characteristics of the colloid cyst, some considerations on its presentation in MRI are presented and a brief survey of the literature is also conducted. CITA: Rev Neurol. 2003 May 1-15;36(9):833-6 DOI: 10.33588/rn.3609.2002522 24

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 12741481 TÍTULO: Pylephlebitis of portal venous system associated with urinary infection AUTORES: Méndez-Sánchez N, Sánchez-Gómez H, Rojas E, Uribe M. SUMMARY: Case report CITA: Dig Dis Sci. 2003 Apr;48(4):834-6 DOI: 10.1023/a:1022873817552 PMID: 12847373 TÍTULO: Prospective study of factors affecting postoperative pain and symp- tom persistence after stapled rectal mucosectomy for hemorrhoids: a need for preservation of squamous epithelium AUTORES: Correa-Rovelo JM, Tellez O, Obregón L, Duque-López X, Mi- randa-Gómez A, Pichardo-Bahena R, Mendez M, Moran S. PURPOSE: The purpose of the study was to determine the variables asso- ciated with postoperative pain and the clinical response of patients with un- complicated hemorrhoidal disease treated with stapled rectal mucosectomy in the medium term. METHODS: Patients with Grade II to IV, uncomplicated hemorrhoidal dis- ease who underwent stapled rectal mucosectomy were prospectively includ- ed. The basal characteristics of the population were evaluated and level of stapling and placement of hemostatic suture determined. Histologically, the type of resected epithelium and presence of muscle fibers was evaluated. Postoperative pain was evaluated by means of a visual analog scale. Com- plications and clinical response were evaluated. RESULTS: One hundred patients with a mean age of 43.9 years were in- cluded. Only columnar epithelium was resected in 48, transitional epithelium in 47, and squamous epithelium in 5 patients. Smooth muscle fragments were found in 55 patients, and, in 12 of these, fibers from the external mus- cular layer of rectum were also seen. Follow-up was 12.6 +/- 3.4 (range, 7-24) months. A total of 79 patients were completely asymptomatic at the end of follow-up. Resected squamous epithelium was associated with a higher postoperative pain level in the multivariate analysis (coefficient beta = 1.16 (95 percent confidence interval, 0.08-2.24); P = 0.035). CONCLUSIONS: Rectal mucosectomy with stapler is an effective method for the treatment of uncomplicated prolapsing hemorrhoidal disease. Intensi- ty of postoperative pain was associated with the type of resected epithelium. This suggests that low transection of hemorrhoids must be avoided. CITA: Dis Colon Rectum. 2003 Jul;46(7):955-62 DOI: 10.1007/s10350-004-6693-z PMID: 14602512 TÍTULO: Imaging diagnosis of subclavian steal syndrome secondary to Takayasu arteritis affecting a left-side subclavian artery AUTORES: Roldán-Valadéz E, Hernández-Martínez P, Osorio-Peralta S, Elizalde-Acosta I, Espinoza-Cruz V, Casián-Castellanos G. 25

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR SUMMARY: Takayasu arteritis (TA) is a rare form of large-vessel, chronic, occlusive vasculitis. It involves mainly aorta and its main branches, causing stenosis and/or obstruction. Its frequency has been estimated at 2.9 cases per 1 million people. Epidemiologically, it is found principally in young fe- male patients and is more prevalent in Asia and Latin America. When there is severe stenosis or occlusion in subclavian artery, the phenomenon of sub- clavian steal syndrome (SSS) occurs, which usually causes symptoms of the vertebrobasilar territory because blood supply to the arm is sustained by reversal of flow in ipsilateral vertebral artery. We describe a case of SSS thought to be due to TA in a Mexican woman. Doppler ultrasound of neck vessels showed retrograde flow in left vertebral artery during systole. Digital subtraction angiography confirmed 30% stenosis of left subclavian artery with filling of left vertebral artery in retrograde direction. In present- ing this case, we carried out a brief review of TA, main features in imaging diagnosis of SSS, and the infrequently reported association of TA with SSS. CITA: Arch Med Res. Sep-Oct 2003;34(5):433-8 DOI: 10.1016/j.arcmed.2003.06.002 PMID: 14606050 TÍTULO: [Pulmonary thromboembolism associated with glioblastoma multi- forme: imaging diagnosis of a case and a review of the literature] AUTORES: Roldán-Valadez E, Salazar-Landa M, Alva-López LF. INTRODUCTION: The incidence of deep vein thrombosis and pulmo- nary embolism in patients with cerebral neoplasia has been estimated at 120/100,000 (the second highest rate for any kind of malignant neoplasia). A timely diagnosis is an indispensable requisite in the clinical evaluation of neurological patients. Patients suffering from glioblastoma multiforme pres- ent a generalized state of hypercoagulability with a deep vein thrombosis incidence after surgery of between 3 and 60%. The incidence with which pulmonary embolism occurs is 5% in patients following neurosurgical opera- tions, with a mortality rate of between 9 and 50%. CASE REPORT: We report the case of a 64 year old male patient with a suspected diagnosis of pulmonary thromboembolism and thrombosis of the right lower limb. Clinical studies included a simple chest X ray, a Doppler ul- trasound recording of the lower limbs, a spiral computed tomography (CAT) scan of the thorax, and a magnetic resonance (MR) scan of the head. The spiral CAT scan showed filling defects in the main pulmonary arteries, a tram track appearance and central filling defects. All these findings are compati- ble with an imaging diagnosis of pulmonary thromboembolism. CONCLUSIONS: The main aim of this study was to describe the use of spiral CAT scanning as a primary tool in the diagnosis of a case. The concurrence of the spiral scan image, the abnormal increase in D dimer and the clinical informa- tion left no doubts about the diagnosis. The clinical manifestations of pulmonary thromboembolism are not specific and therefore the patient s life is at risk. In addition, few reports have been published about the association between glio- blastoma multiforme and the later appearance of pulmonary thromboembolism (a search was conducted in the medical literature from the last 10 years using MEDLINE), and hence we have presented a communication dealing with this pathological association together with a brief review of the clinical diagnosis of pulmonary thromboembolism and its physiopathogenic mechanisms. CITA: Rev Neurol. 2003 Nov 1-15;37(9):831-6 DOI: 10.33588/rn.3709.2003278 26

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 14616928 TÍTULO: Comparative efficacy of eletriptan vs. naratriptan in the acute treat- ment of migraine AUTORES: Garcia-Ramos G, MacGregor EA, Hilliard B, Bordini CA, Leston J, Hettiarachchi J. SUMMARY: This was a randomized, double-blind study designed to evalu- ate the comparative efficacy and tolerability of the 40-mg dose of eletriptan and the 2.5-mg dose of naratriptan. Patients (n = 548) meeting Internation- al Headache Society (IHS) criteria for migraine were randomized to treat a single migraine attack with either eletriptan 40 mg, naratriptan 2.5 mg, or placebo. Headache response rates at 2 h and 4 h, respectively, were 56% and 80% for eletriptan, 42% and 67% for naratriptan (P < 0.01 for both time- points vs. eletriptan), and 31% and 44% for placebo (P < 0.0001 vs. both ac- tive drugs at both time-points). Eletriptan also showed a significantly greater pain-free response at 2 h (35% vs. 18%; P < 0.001) as well as lower use of rescue medication (15% vs. 27%; P < 0.01) and higher sustained head- ache response at 24 h (38%) compared with naratriptan (27%; P < 0.05) and placebo (19%; P < 0.01). Both eletriptan and naratriptan were well tol- erated. The results confirm previous meta-analyses that have suggested the superiority of eletriptan vs. naratriptan in the acute treatment of migraine. CITA: Cephalalgia. 2003 Nov;23(9):869-76 DOI: 10.1046/j.1468-2982.2003.00593.x PMID: 14968476 TÍTULO: [New molecular features of cholestatic diseases of the liver] PMID: 14984668 AUTORES: Méndez-Sánchez N, Chavez-Tapia NC, Uribe M. SUMMARY: Hepatic uptake and biliary excretion of bile salts and non-bile salt organic anions is mediated by specific transport proteins located at the basolateral and canalicular membranes of hepatocytes. Several hepatobili- ary transport systems have been identified and cloned over the past years. This development has facilitated molecular biological and genetic analyses of these transporters in experimental cholestasis and human cholestatic liver diseases. Evidence now exists that decreased or even absent expression of hepatobiliary transport systems may explain impaired transport function resulting in hyperbilirubinemia and cholestasis. This review summarizes the molecular defects in hepatocellular membrane transporters associated with hereditary and acquired forms of cholestatic liver diseases. The increasing information on the molecular regulation of hepatobiliary transport systems should bring new insights into the pathophysiology and treatment of human cholestatic liver diseases. CITA: Rev Invest Clin. Sep-Oct 2003;55(5):546-56 TÍTULO: [Laparoscopic appendectomy. Surgical technique description and literature review] AUTORES: Alvarado-Aparicio A, Moreno-Portillo M, Pereira-Graterol F, Rojano-Rodríguez M, González-Monroy L, Palacios-Ruiz A. INTRODUCTION: The laparoscopic appendectomy (LA) is considered a surgical process of controversy, although it offers better recovery and better aesthetic results, and allows visualization of the abdominal cavity. In this work, we presented a revision of the topic and the experience of our group in the Endoscopic Surgery Unit at the Dr. Manuel Gea González General Hospital and at the Hospital Médica Sur, both in Mexico City. 27

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PATIENTS AND METHODS: We conducted a retrospective study, random- ized, which included patients with LA from January 1, 1993 to December 31, 2002. All were operated on by the same group of surgeons. No exclusion criterion existed for the procedure. The surgical technique used in studied patients is described. RESULTS: We operated on 218 patients; 69% were women of 10 to 78 years of age with a 27 years-of-age average. Surgical time varied from 20 to 90 min with an average of 35 min. Hospitalization lasted 1 to 5 days, with an average of 2 days. We found peritonitis in 23%. In 202 patients, diagnosis of appendicitis was confirmed; only in 16 patients was diagnosis different. Surgical technique was the same during the entire time. We used the Gea knot with polypropylene to tie off the appendix and appendicular artery. In cases of peritonitis, irrigation was not used, but only aspiration, cleaning with gauzes, and placement of drainages. Mortality was not reported. CONCLUSIONS: LA offers advantages over AA whenever it is carried out by an experienced laparoscopic surgeon. Peritonitis is not a contraindication for LA, and it is not necessary to irrigate with solution for cleaning the peritoneal cavity. CITA: Cir Cir. Nov-Dec 2003;71(6):442-8 PMID: 15041898 TÍTULO: Images in hepatology. Microhamartomas (Von Meyenburg Comple- PMID: 15041898 xes) PMID: 15041899 AUTORES: Méndez-Sánchez N, Pichardo-Bahena R, Uribe M. SUMMARY: Case report CITA: Ann Hepatol. Apr-Jun 2003;2(2):98. TÍTULO: Images in hepatology. Microhamartomas (Von Meyenburg Comple- xes) AUTORES: Méndez-Sánchez N, Pichardo-Bahena R, Uribe M. SUMMARY: Case report CITA: Ann Hepatol. Apr-Jun 2003;2(2):98. TÍTULO: Hepatic Echinococcus granulosus. A case report AUTORES: Méndez-Sánchez N, Vega R, Cortés R, Corona R, Pichardo- -Bahena R, Uribe M. SUMMARY: A 32-year-old woman was admitted to hospital complaining of right upper quadrant and epigastrium abdominal pain, and nausea. On rou- tine physical examination an abdominal mass was discovered on the right upper quadrant. Liver tests were normal. Magnetic resonance imaging of the abdomen revealed a low-density cystic mass. A cystectomy was performed. Hydatid sand containing a protoscolex of Echinococcus granulosus was seen on microscopical examination. Specific antiparasitic treatment was giv- en and after two months the patient is asymptomatic. CITA: Ann Hepatol. Apr-Jun 2003;2(2):99-100 DOI: 10.1016/S1665-2681(19)32149-0 28

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 15094706 TÍTULO: Hepatocellular carcinoma not associated with virus B and C and alcohol AUTORES: Dardón A, Corona R, Méndez-Sánchez N. SUMMARY: Case report CITA: Ann Hepatol. Jan-Mar 2003;2(1):46 DOI: 10.1016/S1665-2681(19)32158-1 PMID: 15115958 TÍTULO: Hepatic fascioliasis PMID: 15115959 AUTORES: Pichardo-Bahena R, Almeda-Valdés P, Méndez-Sánchez N. PMID: 15115963 SUMMARY: Case report CITA: Ann Hepatol. Oct-Dec 2003;2(4):182. DOI: 10.1016/S1665-2681(19)32131-3 TÍTULO: Hypertransaminasemia and severe hepatic steatosis without in- flammation. A case report AUTORES: Méndez-Sánchez N, Motola-Kuba D, Bahena-Aponte J, Chavez- Tapia N, Pichardo-Bahena R, Uribe M. SUMMARY: Nonalcoholic fatty liver disease (NAFLD) is a medical condition that may progress to end-stage liver disease. The spectrum of NAFLD is wide and ranges from simple fat accumulation in hepatocytes (steatosis), to fat accumulation plus necroinflammatory activity with or without fibrosis (ste- atohepatitis). In addition, NAFLD is the most common cause of abnormal liv- er-test results among adults with a prevalence of 13%-23%. This case report is an example of a patient with asymptomatic hypertransaminasemia and severe hepatic steatosis without inflammation in which the diagnosis was made by liver biopsy. CITA: Ann Hepatol. Oct-Dec 2003;2(4):183-5 DOI: 10.1016/S1665-2681(19)32132-5 TÍTULO: Hepatic encephalopathy: a review AUTORES: Lizardi-Cervera J, Almeda P, Guevara L, Uribe M. SUMMARY: Hepatic encephalopathy (HE) is a complication that presents in as many as 28% of patients with cirrhosis, and reported up to ten years after the diagnosis of cirrhosis. Commonly, it is observed in patients with severe hepatic failure and is characterized by neuropsychiatric manifestations that can range in severity from a mild alteration in mental state to a coma; addi- tionally, some neuromuscular symptoms can be observed. This complication of either acute or chronic hepatic disease is the result of a diminished hepat- ic reservoir and inability to detoxify some toxins that originate in the bowel. Today, the role of astrocytes, specifically the Alzheimer type II cells, is known to be very important in the pathogenesis of the hepatic encephalopathy, and will be reviewed later. In conclusion, the objectives of this review are: To 29

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR understand the pathogenesis of hepatic encephalopathy, To recognize the precipitating factors, as well as preventive measures for the development of the hepatic encephalopathy, To describe the new classification of hepatic en- cephalopathy and its clinical implications, To recognize the clinical manifes- tations and stages of the disease, To understand the main diagnostic tests used to detect the hepatic encephalopathy, To describe the main therapeutic treatments of hepatic encephalopathy. CITA: Ann Hepatol. Jul-Sep 2003;2(3):122-30. DOI: 10.1016/S1665-2681(19)32137-4 2004 PMID: 15022894 TÍTULO: [Imaging diagnosis of acute septic arthritis of hip] AUTORES: Roldán-Valadez E, Lima-Dávalos R, Sangri-Pinto G, Solórzano- -Morales S, Hernández-Ortiz J. SUMMARY: Acute septic arthritis is a common diagnosis usually seen by radiologists, internists, and family physicians; it is most commonly caused by pyogenic pathogens. In the majority of patients, it is possible to identify, the infection mechanism: spread of infection can be due to hematogenous dissemination, a contiguous source of infection, direct inoculation, or sur- gical contamination. Radiologic findings include increase in articular space and central and marginal bone erosions; the first plain radiograph changes are seen 8-10 days after symptoms. We present the case of a 9-year-old girl with septic arthritis of right hip; in presenting this case we offer a brief summary of clinical features and main imaging findings of septic arthritis (plain radiographs, ultrasonography, and gammagraphy). CITA: Gac Med Mex. Jan-Feb 2004;140(1):93-5 PMID: 15118577 TÍTULO: Etiology of liver cirrhosis in Mexico AUTORES: Méndez-Sánchez N, Aguilar-Ramírez JR, Reyes A, Dehesa M, Juárez A, Castñeda B, Sánchez-Avila F, Poo JL, Guevara González L, Liz- ardi J, Valdovinos MA, Uribe M, Contreras AM, Tirado P, Aguirre J, Rive- ra-Benítez C, Santiago-Santiago R, Bosques-Padilla F, Muñoz L, Guerrero A, Ramos M, Rodríguez-Hernández H, Jacobo-Karam J BACKGROUND: In the last decades it has been suggested that the main cause of liver cirrhosis in Mexico is alcohol. Currently in Western countries hepatitis C virus stage liver disease and liver transplantation. In Mexico, we have no data relative to the etiology of liver cirrhosis. The aim of this study was to investigate the main causes of liver cirrhosis in Mexico. METHODS: Eight hospitals located in different areas of the country were in- vited to participate in this study. Those hospitals provide health care to differ- ent social classes of the country. The inclusion criteria were the presence of either an histological or a clinical and biochemical diagnosis of liver cirrhosis. RESULTS: A total 1,486 cases were included in this study. The etiology of liver cirrhosis was alcohol in 587 (39.5%), HCV 544 (36.6%), cryptogenic 154 (10.4%), PBC 84 (5.7%), HBV 75 (5.0%) and other 42 (2.8%). There was no statistical difference between alcohol and HCV. 30

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR CONCLUSIONS: We conclude that the main causes of liver cirrhosis in Mex- ico are alcohol and HCV. CITA: Ann Hepatol. Jan-Mar 2004;3(1):30-3 DOI: 10.1016/S1665-2681(19)32122-2 PMID: 15144045 TÍTULO: [An update on non-alcoholic fatty liver disease] AUTORES: Méndez-Sánchez N, Chávez-Tapia NC, Uribe M. SUMMARY: Non alcoholic fatty liver disease is a disease of emerging identity and importance. It is frequently associated with obesity, especially visceral fat, and is intimately related to fatty liver and markers of insulin resistance. Both the prevalence and the severity of liver steatosis are related to body mass index, waist circumference, hyperinsulinaemia, hypertriglyceridaemia and impaired glucose tolerance or type 2 diabetes. The identification fatty liver disease in obese patients, is very important in order to prevent compli- cations such as steathohepatitis and cirrhosis. The pathogenesis of non alco- holic fatty liver disease is very complex, there are mitochondrial morphologic and functional alterations, as well as, high sensitivity to injurious stimulus, an increased inflammatory activity, and modifications in cellular metabolism at post-receptor level. Weight reduction is one of the first steps in the treatment of patients with non alcoholic fatty liver disease, as well as the management of associated conditions such as obesity, diabetes mellitus and hyperlipidae- mia. Antioxidants, and others drugs such as ursodeoxycholic acid may be beneficial in the treatment of non alcoholic fatty liver disease. These medi- cations, however, need first to be tested in well-controlled trials with clinically relevant end-points and extended follow-up. In this review, we analyze the new concepts in epidemiology, pathophysiology and treatment of this disease. CITA: Rev Invest Clin. Jan-Feb 2004;56(1):72-82 PMID: 15257249 TÍTULO: The relationship of overweight and obesity to high mortality rates from liver cirrhosis in Mexico AUTORES: Méndez-Sánchez N, Sánchez-Castillo CP, Villa AR, Madrigal H, Merino B, García E, López P, Pichardo-Ontiveros E, Uribe M. BACKGROUND & AIM: Liver cirrhosis continues to be an important cause of death in Mexico. Some data suggest that being overweight is a risk factor for chronic liver disease. The aim of this study was to assess the link be- tween the incidences of being overweight or obese and mortality from liver cirrhosis in Mexico during the period 1990-2001. METHODS: We designed and conducted an ecological study of trends with multiple comparisons of regions of Mexico (North, Central, Mexico City, and South). We built the time trends according to the mortality rates of liver cir- rhosis reported by the System of Vital Statistics (Health Ministry) in each state for each year from 1990 to 2001. The information on prevalences of overweight (body mass index (BMI) = 25-29.9) and obesity (BMI >/= 30) was from two national surveys (1993 and 2000). RESULTS: The analysis of mortality trends in liver cirrhosis by region showed an increase in the risk of death across time. This risk was consid- erably higher for the South Region (beta = 1.03, p <0.0001). The mortality rates remained higher than 30 per 100,000 inhabitants. When we selected the three states with the highest mortality rates for each region, the most 31

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR significant changes in the trends were in the North and South regions (beta = 0.75, p <0.0001 and beta = 1.29, p <0.0001, respectively). In addition, the prevalence of overweight in the four regions increased from 1993 to 2000 (percentage change, 10.2-48.2). Obesity was most prevalent in the North and South regions in 1993. CONCLUSION: Our observations support the hypothesis that obesity might play an important role in the risk of developing liver cirrhosis. CITA: Ann Hepatol. Apr-Jun 2004;3(2):66-71 DOI: 10.1016/S1665-2681(19)32111-8 PMID: 15257252 TÍTULO: Infectious mononucleosis hepatitis: a case-report PMID: 15365034 AUTORES: Méndez-Sánchez N, Uribe M. PMID: 15505596 SUMMARY: 46-year-old Mexican-born who lived in Mexico City was admit- ted to the hospital for evaluation with a two-week history of fever, jaundice, and malaise. Physical examination he had cardiac murmurs. The liver was palpable 2 cm below the costal margins. Liver-function tests showed hyper- transaminasemia. The patient had a high titer of anti-EBV IgM antibodies, but tests for all other antiviral antibodies were negative. The liver biopsy shows EBV latent membrane protein. CITA: Ann Hepatol. Apr-Jun 2004;3(2):75-6 DOI: 10.1016/S1665-2681(19)32114-3 TÍTULO: Prevalence of hepatitis C virus infection among hemodialysis pa- tients at a tertiary-care hospital in Mexico City, Mexico AUTORES: Méndez-Sánchez N, Motola-Kuba D, Chavez-Tapia NC, Bahena J, Correa-Rotter R, Uribe M. SUMMARY: We determined the prevalence of hepatitis C virus (HCV) in he- modialysis patients by antibody testing and HCV RNA determination by PCR. A total of 149 patients with kidney failure with replacement therapy were test- ed. The prevalence of anti-HCV was 6.7% (10 of 149 patients), and viremia was detectable in 8 of 149 (5%) patients. Three of 149 patients (2%) were anti-HCV negative with detectable HCV RNA. CITA: J Clin Microbiol. 2004 Sep;42(9):4321-2 DOI: 10.1128/JCM.42.9.4321-4322.2004 TÍTULO: Weight reduction and ursodeoxycholic acid in subjects with nonal- coholic fatty liver disease. A double-blind, placebo-controlled trial AUTORES: Méndez-Sánchez N, González V, Chávez-Tapia N, Ramos MH, Uribe M. OBJECTIVE: Nonalcoholic fatty liver disease is an increasingly recognized condition that may progress to end-stage liver disease. We investigated the effects of weight reduction and ursodeoxycholic acid administration in pa- tients with this disease. 32

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR RESEARCH METHODS AND PROCEDURES: A double-blind, placebo-con- trolled trial. Twenty-seven women with a body mass index of >30 kg/m2 and willing to participate in the diet plan for six weeks were studied were as- signed to one of two treatment groups (ursodeoxycholic acid, n = 14: pla- cebo n = 13). Both groups received a normal diet (1,200 kcal/d) plus 1200 mg/d of ursodeoxycholic acid or placebo. Hepatic steatosis, was assessed by abdominal ultrasound. Fasting glucose, cholesterol, triglycerides, and aminotransferases levels were determined before and after treatment. RESULTS: Body mass index decreases significantly from 34.2 +/- 4.2 kg/m2 and 33.3 +/- 1.6 kg/m2 to 31.8 +/- 4.5 kg/m2 and 30.6 +/- 2.6 kg/m2 in the ursodeoxycholic acid and placebo groups, p < 0.001. The hepatic steatosis index decreased from 2.3 +/- 0.7 to 1.0 +/- 0.6 and 2.2 +/- 0.7 to 1.1 +/- 0.7 in the ursodeoxycholic acid and placebo groups, p<0.003. Serum AST de- creased significantly from 41.2 +/- 5.6 to 34.5 +/- 3.4 in the ursodeoxycholic acid group, p <0.001, and from 43.6 +/- 4.2 to 35.3 +/- 2.9 in the placebo group, p <0.001. Serum ALT decreased from 62.9 +/- 6.5 to 44.0 +/- 3.5 in the ursodeoxycholic acid group, p <0.001, and from 63.5 +/- 4.5 to 44.0 +/- 3.5 in the placebo group. We did not find any differences in all variables studied between groups. CONCLUSIONS: The present study shows beneficial effect of weight reduc- tion, producing improvements in biochemical and imaging markers of liver disease. CITA: Ann Hepatol. Jul-Sep 2004;3(3):108-12 DOI: 10.1016/S1665-2681(19)32103-9 PMID: 15546256 TÍTULO: Triple combination of thymalfasin, peginterferon alfa-2a and riba- virin in patients with chronic hepatitis C who have failed prior interferon and ribavirin treatment: 24-week interim results of a pilot study AUTORES: Poo JL, Sánchez-Avila F, Kershenobich D, García-Samper X, Gongora J, Uribe M. SUMMARY: Despite steady progress in antiviral treatment for patients with chronic hepatitis C virus (HCV), many patients still have detectable serum HCV RNA levels by the end of interferon-based treatment and are known as virological non-responders. Re-treatment of these patients not respond- ing to previous therapy remains challenging. Studies of the dynamics of the HCV population show a marked decline in new cases since 1996; howev- er, the relative proportion of non-responders is expected to increase over time and, similarly, the number of patients eligible for first-line treatment is expected to decrease. The current standard of care for treatment involves the use of pegylated interferons in combination with ribavirin. However, many difficult-to-treat groups still have low response rates. Newer combinations are being investigated to optimize chances of attaining a sustained response in these groups: one such triple therapy regimen is peginterferon alfa-2a, ribavi- rin and thymalfasin, which was given to 23 previously non-responder patients. Viral response was 60.8% at week 12 and 47.8% at week 24. These prelimi- nary results encourage further evaluation of this promising combination. CITA: J Gastroenterol Hepatol. 2004 Dec;19 Suppl 6:S79-81 DOI: 10.1111/j.1440-1746.2004.03634.x 33

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 15554998 TÍTULO: The Amerindian's genes in the Mexican population are associated with development of gallstone disease AUTORES: Méndez-Sánchez N, King-Martínez AC, Ramos MH, Pichardo- -Bahena R, Uribe M. BACKGROUND: It has been suggested that genes related to Amerindian ancestry account for the high prevalence of gallstone disease (GD) observed in Mexican-Americans. The HLA-B39 is an allele found in higher frequency in Amerindians whereas HLA-B15 is rarely found. The aim of this study was to test the hypothesis that gallstone susceptibility genes are more prevalent in Mexicans with recent Amerindian ancestry. METHODS: We carried out a prospective case-controlled study. Subjects were divided into those who had stones visible on gallbladder ultrasound (cases), and those whose ultrasounds were negative for gallstones (con- trols). Body mass index (BMI) was calculated, and serum lipids and lipopro- tein, and glucose levels were measured. Class I HLA (HLA-B) typing was performed by PCR amplification of genomic DNA. RESULTS: Of the 1,101 subjects, 146 were classified as subjects with GD (cases) and 955 as subjects without GD (controls). Mean age of the cases was 53.5 +/- 12.5 yr versus 44.78 +/- 12.0 yr for the controls, p= 0.001. A family history of GD was observed in 48% of the cases versus 28.4% of the controls, p= 0.001. HLA-B39 was more frequently increased in GD subjects (0.162), compared with controls (0.063), p= 0.008. The odds ratio of having HLA-B39 was 2.8 and 95% (CI 95%= 1.3-6.3) for GD; HLA-B15 was more frequently increased in controls than in cases. CONCLUSIONS: The most prevalent HLA alleles detected in these GD cas- es are characteristic of Amerindian populations, supporting the role of genet- ics in the high prevalence of the development of GD in Mexican mestizos. CITA: Am J Gastroenterol. 2004 Nov;99(11):2166-70 DOI: 10.1111/j.1572-0241.2004.40159.x PMID: 15612524 TÍTULO: [In search of lost ethics. About gifts that pharmaceutical industry offers to physicians] AUTORES: Rosete-Reyes A. SUMMARY: Review article CITA: Rev Invest Clin. May-Jun 2004;56(3):399-405 PMID: 15641210 TÍTULO: Triple combination of thymalfasin, peginterferon alfa-2a and riba- virin in patients with chronic hepatitis C who have failed prior interferon and ribavirin treatment: 24-week interim results of a pilot study AUTORES: Poo JL, Sánchez-Avila F, Kershenobich D, García-Samper X, Gongora J, Uribe M. SUMMARY: Despite steady progress in antiviral treatment for patients with chronic hepatitis C virus(HCV), many patients still have detectable serum HCV RNA levels by the end of interferon-based treatment and are known as virological non-responders. Re-treatment of these patients not respond- 34

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR ing to previous therapy remains challenging. Studies of the dynamics of the HCV population show a marked decline in new cases since 1996; howev- er, the relative proportion of non-responders is expected to increase over time and, similarly, the number of patients eligible for first-line treatment is expected to decrease. The current standard of care for treatment involves the use of pegylated interferons in combination with ribavirin. However, many difficult-to-treat groups still have low response rates. Newer combinations are being investigated to optimize chances of attaining a sustained response in these groups: one such triple therapy regimen is peginterferon alfa-2a, ribavi- rin and thymalfasin, which was given to 23 previously non-responder patients. Viral response was 60.8% at week 12 and 47.8% at week 24. These prelimi- nary results encourage further evaluation of this promising combination. CITA: J Gastroenterol Hepatol. 2004 Dec;19(12):S79-81 PMID: 15641470 TÍTULO: [Obesity and steatohepatitis. Histologic aspects] PMID: 15641472 AUTORES: Pichardo-Bahena R, Paz-Gómez FJ, Estrada-Villaseñor EG. SUMMARY: The traditional concept of adipose tissue as a passive reser- voir for energy storage is no longer valid because it has been demonstrated that adipose tissue is a complex, essential, and highly active metabolic and endocrine organ that not only responds to afferent signals from traditional hormone systems and the central nervous system (CNS), but also express- es and secretes factors with important endocrine functions. These factors include leptin and other cytokines. Adipose tissue is also a major site for me- tabolism of sex steroids and glucocorticoids. The important endocrine func- tion of adipose tissue is emphasized by adverse metabolic consequences of both adipose tissue excess and deficiency. Adipose tissue excess, particu- larly in visceral compartment, is associated with insulin resistance, hypergly- cemia, dyslipidemia, hypertension, and prothrombotic and proinflammatory states. Liver is one of the principal targets of lipid-associated damage by mechanisms that involve apoptosis activation by source of tumoral necrosis factor-alpha and caspase activation and liberation of oxygen-reactive spe- cies by oxidative stress and enzymatic chains such as P450, CYP2E1, and CYP3A4, resulting in a continuum involving non alcohol-related fatty liver, non-alcoholic steatohepatitis with or without fibrosis, and liver cirrhosis. This work presents an overview of endocrine functions of adipose tissue and its influence on mechanisms of liver damage. CITA: Gac Med Mex. Jul-Aug 2004;140 Suppl 2:S33-40 TÍTULO: [Obesity and dyslipidemias] AUTORES: Troyo-Barriga P. SUMMARY: Obesity is an important world-wide public health problem. One of the most deletereous metabolic derangements of the disease is the dys- lipidemia frequently involved that is highly atherogenic. The usual pheno- typic pattern is fasting hypertriglyceridemia, non-HDL post-prandial hyper- lipidemia anda real increased production of small-dense LDL particles, as well as low production of HDL cholesterol. An integral therapeutic plan on obese dyslipidemic patients must include always the identification and man- agement of risk factors that interact within the disease, as well as to know its pharmacological risk-benefit ratio. In the future, new therapeutic tools tar- 35

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR geting deranged metabolic pathways (as pharmacogenomics) could correct in a cascade fashion other comorbid conditions commonly found in obesity. CITA: Gac Med Mex. Jul-Aug 2004;140 Suppl 2:S49-58 PMID: 15641473 TÍTULO: [Gallbladder disease and obesity] PMID: 15641474 AUTORES: Méndez-Sánchez N, Chávez-Tapia NC, Uribe M. SUMMARY: Gallbladder disease is a very common diagnosis and implies great economic cost. Gallbladder disease is a multifactorial process involved with host and environmental factors. Obesity is considered one of the most important risk factor associated with gallstone disease and is very important mainly due its increased prevalence worldwide. Several changes in choles- terol metabolism tend to increase gallbladder cholesterol secretion in con- junction with motility disturbances, which aids in gallstone growth. In this work, epidemiologic and pathophysiologic factors related with obesity and gallstone disease are discussed. CITA: Gac Med Mex. Jul-Aug 2004;140 Suppl 2:S59-66 TÍTULO: [Obesity and non-alcoholic steatohepatitis] AUTORES: Méndez-Sánchez N, Chávez-Tapia NC, Uribe M. SUMMARY: Obesity is the most important risk factor associated with non-al coholic steatohepatitis, which is caused by to impaired insulin activity, over- flow of portal triglycerides, and production of inflammatory cytokines; all of these are deleterious to hepatocytes. These phenomena facilitate disrup- tions in hepatic physiology, as observed in alcoholic hepatitis; however, con- sumption of this substance is absent. Non-alcoholic steatohepatitis has had a great impact due to the fact that previously, main cases of cryptogenic cirrhosis actually were attributed to this disease. Despite advances in un- derstanding the pathophysiologic process of the disease, there is no better treatment than weight reduction (a combination of diet and exercise). In this issue, we describe the most important topics with regard to non-alcoholic steatohepatitis and the obesity-related process. CITA: Gac Med Mex. Jul-Aug 2004;140 Suppl 2:S67-72 PMID: 15641476 TÍTULO: [Obesity and its association with cryptogenic cirrhosis and hepato- carcinoma] AUTORES: Lizardi-Cervera J, Motola-Kuba D, Guevara-González L. SUMMARY: Obesity is a rapidly growing health issue in Mexico and through- out the world because it is perceived as an alarming threat directly related with lifestyle in both children and adults, although cardiovascular, metabolic, neoplasic, and sleep-disorder complications of obesity are being investigat- ed. However, overweight is a risk factor for chronic liver disease because liver fibrosis can develop in overweight patients free of any other known causes of liver disease. Obesity has been associated with development of hepatocellular carcinoma. CITA: Gac Med Mex. Jul-Aug 2004;140 Suppl 2:S77-83 36

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 15641478 TÍTULO: [Pharmacological treatment for obesity] PMID: 15657560 AUTORES: Mancillas-Adame L, Morales-González G. SUMMARY: The pharmacological treatment of obesity is just one of the ther- apeutic weapons that the multidisciplinary team involved in the treatment of the obese patients must use, it is helpful in order to achieve better adher- ence to nutritional and lifestyle modifications. The indications and agents used in the treatment of the obese patients are reviewed. CITA: Gac Med Mex. Jul-Aug 2004;140 Suppl 2:S91-5 TÍTULO: Acute liver failure and the Molecular Adsorbents Recirculating Sys- tem: early experience in a tertiary care hospital in Mexico City AUTORES: Méndez-Sánchez N, Chávez-Tapia NC, Espinoza B, Herrera- -Gomar M, Zamora-Valdés D, Uribe M. SUMMARY: Acute liver failure is a clinical condition associated with high mor- tality despite recent technological advances. Supportive devices such as the Molecular Adsorbents Recirculating System (MARS®) provide therapeutic strategies to add time to find an organ for orthotopic liver transplantation or to allow the native liver to recover sufficiently to make transplantation unnec- essary. In this series of cases, we discuss our initial experiences with three patients with acute liver failure. One patient had high bilirubin levels caused by Epstein-Barr virus infection and responded well after three MARS sessions. In a second patient, MARS therapy was used to treat acute-on-chronic liver failure caused by chronic hepatitis B virus infection that had not been treated previously; because of severe hemodynamic compromise, only one MARS session was performed. The third patient had an initial diagnosis of acute liver failure and cryptogenic hepatitis, and was treated with five MARS sessions as a supportive measure until the definitive diagnosis (metastatic disease) was performed. In all patients, MARS therapy was well tolerated and induced only mild hypokalemia. In conclusion, although MARS therapy was an effective strategy for these cases of liver failure and greatly improved the biochemical variables, its impact on the mortality rate has not yet been determined. CITA: Ann Hepatol. Oct-Dec 2004;3(4):164-6 DOI: 10.1016/S1665-2681(19)32096-4 PMID: 15690609 TÍTULO: Asymptomatic true gallbladder duplication: a case report and re- view of the literature AUTORES: Roldan-Valadez E, Osorio-Peralta S, Vivas-Bonilla I, Vazquez-LaMadrid J, Alva-Lopez LF, Hernandez-Ortiz J. SUMMARY: Gallbladder duplication is a rare event, with an incidence at autopsy of about 1/4000, with very few documented symptomatic cases re- ported. Preoperative diagnosis and differentiation of this malformation are important to prevent inadvertent damage to the biliary system, a complicated postoperative course, and repeat surgery. We present a case of true gall- bladder duplication found incidentally during abdominal ultrasonography (US). The diagnosis was made with US and the Y-type duplication was demonstrated with magnetic resonance cholangiopancreatography (MRCP). CITA: Acta Radiol. 2004 Dec;45(8):810-4 DOI: 10.1080/02841850410008298 37

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR 2005 TÍTULO: Stereotactic noninvasive volume measurement compared with geometric measurement for indications and evaluation of gamma knife treat- PMID: 15662797 ment AUTORES: del Valle R, Pérez M, Ortiz J, Ruiz S, de Anda S, Jaramillo J, Martínez M, Corona R, Vivas I, Facha T, Olmos R, Arrieta A, Estrada J. OBJECT: Volume estimation is one of the most important criteria in the evalua- tion and follow up of radiosurgical treatments and outcomes; however, several limitations are involved in the calculation estimation of target volumes. METHODS: Retrospective and prospective studies were conducted to eval- uate the efficacy of a new noninvasive stereotactic method when it is com- pared with geometric volume calculation of intracranial tumors for planning stereotactic radiosurgery treatment as well as for follow up and outcome evaluation. Two equations were created that permit comparison of the cal- culated and measured volumes. These equations took linear and quadratic forms, respectively. Volume estimation using the stereotactic approach com- pared with traditional volume calculation gave more accurate results regard- less of the shape and size of the lesion. CONCLUSIONS: The use of stereotactic volume calculation is highly recom- mended in planning, follow up, and determination of the outcome in patients participating in radiosurgical treatment and should lead to more uniform re- ports of the response to treatment. CITA: J Neurosurg. 2005 Jan;102 Suppl:140-2 DOI: 10.3171/jns.2005.102.s_supplement.0140 PMID: 15754751 TÍTULO: [Clinical evolution in two patients with Wiskott-Aldrich Syndrome] AUTORES: Baptista-González H, Alvarez-Amaya C. SUMMARY: Case report CITA: Gac Med Mex. Jan-Feb 2005;141(1):47-51 PMID: 15754754 TÍTULO: [Secondary non-Hodgkin's B-cell lymphoma involving the breast: radiologic imaging] AUTORES: Roldán-Valadez E, García-Blanco Mdel C, Rojas-Marín C, Sán- chez-Avila F, León-Rodrìguez E, Hernández-Ortiz J. SUMMARY: Secondary lymphomas involving the breast, although uncom- mon, represent the largest group of metastasic tumors to the breast. Primary non-Hodgkin lymphomas (NHLs) of the breast are also rare, accounting for 1.7% to 2.2% of extranodal NHL cases and 0.38 to 0.7% of all NHLs. Ap- proximately 300 cases have been reported in the Medical literature. Mam- mographic appearances are described as round or oval areas of opacity. The breast mass may appear homogeneous or inhomogeneous. The lesion may be very well defined and may be mistaken for a benign process, most notable 38

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR in patients younger than 35 years of age. Ultrasonographic appearance is de- scribed as a sharply defined mass with low or medium echoes. The posterior aspect of the mass is well defined (possibly with slight acoustic enhancement but with no associated posterior shadowing). In summary, the mammograph- ic appearance of the breast lymphoma is nonspecific, but the diagnosis can possibly be excluded if calcifications or a desmoplastic reaction are present. Prominent lymph vessels in a patient with a breast mass should raise the sus- picion of breast lymphoma. The most critical aspect in the workup of a breast mass is the tissue biopsy, since radiographically lymphomatous lesions are indeterminate. We present the case of a 79-year-old woman with abdominal pain and a palpable breast mass; we also make a brief summary of the clini- cal features and main imaging findings of NHL (plain radiograph, mammogra- phy, breast ultrasound and thorax tomography). CITA: Gac Med Mex. Jan-Feb 2005;141(1):63-7 PMID: 15784027 TÍTULO: Strong association between gallstones and cardiovascular disease AUTORES: Méndez-Sánchez N, Bahena-Aponte J, Chávez-Tapia NC, Motola-Kuba D, Sánchez-Lara K, Ponciano-Radríguez G, Ramos MH, Uribe M. BACKGROUND AND AIM: Obesity is closely associated with the increased morbidity and mortality of many common diseases in the Western world, including coronary heart disease (CHD) and gallstone diseases (GD). We have investigated the association between GD and CHD in a cross-sectional study. METHODS AND RESULTS: Subjects who had gallstones visible by ultra- sound were considered as cases and subjects negative for gallstones were classified as controls. Positive CHD was defined when the stress test was positive. Body mass index (BMI), waist circumference, blood pressure, se- rum lipid concentrations, and insulin resistance were measured. The associ- ation was estimated by odds ratios using logistic regression models adjust- ed for confounders. Four hundred and seventy-three subjects (292 males and 181 females) were included, comprising 354 controls and 119 cases. Subjects with GD had higher prevalence of CHD (15.96%) than controls (4.52%) (p < 0.0001). In univariate unconditional logistic regression analysis CHD, BMI >/= 30 kg/m(2), waist circumference, high blood pressure, and HOMA-IR > 2.5 were the most important risk factors for GD. In multivariate analysis (adjusted for age and gender, and BMI) the risk for GD in subjects with CHD was higher (OR 2.84, 95% CI: 1.33-6.07, p < 0.007). CONCLUSIONS: Subjects with CHD have an increased risk to have GD, both diseases are strongly associated and the main characteristics of these subjects are those frequently involved as part of the metabolic syndrome. CITA: Am J Gastroenterol. 2005 Apr;100(4):827-30 DOI: 10.1111/j.1572-0241.2005.41214.x PMID: 15786544 TÍTULO: Metabolic syndrome as a risk factor for gallstone disease AUTORES: Méndez-Sánchez N, Chavez-Tapia NC, Motola-Kuba D, San- chez-Lara K, Ponciano-Rodríguez G, Baptista H, Ramos MH, Uribe M. AIM: To establish an association between the presence of metabolic syn- drome and the development of gallstone disease. 39

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR METHODS: We carried out a cross-sectional study in a check-up unit in a university hospital in Mexico City. We enrolled 245 subjects, comprising 65 subjects with gallstones (36 women, 29 men) and 180 controls (79 women and 101 men without gallstones). Body mass index, waist circumference, blood pressure, plasma insulin, and serum lipids and lipoproteins levels were measured. Insulin resistance was calculated by homeostasis model assessment. Unconditional logistic regression analysis (univariate and mul- tivariate) was used to calculate the risk of gallstone disease associated with the presence of at least three of the criteria (Adult Treatment Panel III). Anal- yses were adjusted for age and sex. RESULTS: Among 245 subjects, metabolic syndrome was present in 40% of gallstone disease subjects, compared with 17.2% of the controls, adjusted by age and gender (odds ratio (OR) = 2.79; 95%CI, 1.46-5.33; P = 0.002), a dose-dependent effect was observed with each component of metabolic syndrome (OR = 2.36, 95%CI, 0.72-7.71; P = 0.16 with one component and OR = 5.54, 95%CI, 1.35-22.74; P = 0.02 with four components of metabol- ic syndrome). Homeostasis model assessment was significantly associated with gallstone disease (adjusted OR = 2.25; 95%CI, 1.08-4.69; P = 0.03). CONCLUSION: We conclude that as for cardiovascular disease and diabe- tes mellitus, gallstone disease appears to be strongly associated with meta- bolic syndrome. CITA: World J Gastroenterol. 2005 Mar 21;11(11):1653-7 DOI: 10.3748/wjg.v11.i11.1653 PMID: 15793855 TÍTULO: Adiponectin as a protective factor in hepatic steatosis AUTORES: Mendez-Sanchez N, Chavez-Tapia NC, Villa AR, Sanchez-La- ra K, Zamora-Valdes D, Ramos MH, Uribe M. AIM: Obesity and insulin resistance (IR) are closely related to hepatic ste- atosis (HS), and adiponectin is a hepatic insulin sensitizer that has important effects in liver function. This study aims at investigating the relationship be- tween serum adiponectin concentration and the presence of HS. METHODS: We carried out a cross-sectional study in a check-up unit of a University Hospital in Mexico City. We enrolled 196 subjects, comprising 98 subjects with HS (27 women, 71 men) and 98 controls (37 women and 61 men). Anthropometric, metabolic and biochemical variables were mea- sured in the two groups. Serum adiponectin and leptin concentrations were determined, their association with grade of HS tested, and concentrations, according to quartiles, compared between cases and controls. chi(2) anal- ysis for linear trends was used to test for a dose-response relationship and logistic regression analysis was conducted to test for a protective effect of adiponectin. RESULTS: The HS subjects were older and more obese than controls, with a central obesity pattern. In the fourth quartile of adiponectin concentrations, HS was less common and severe. In a multivariate model of the fourth quar- tile of the adiponectin concentrations, we observed a protective effect (OR = 0.17, 95%CI: 0.04-0.67, P = 0.01). In subjects with more severe HS, we observed higher leptin concentrations, and caloric intakes, total fat and iron consumption were higher than in controls. 40

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR CONCLUSION: The results of the present study suggest that a high serum concentration of adiponectin is associated with a protective effect against HS. CITA: World J Gastroenterol. 2005 Mar 28;11(12):1737-41 DOI: 10.3748/wjg.v11.i12.1737 PMID: 15798659 TÍTULO: Alcoholic liver disease. An update AUTORES: Méndez-Sánchez N, Almeda-Valdés P, Uribe M. SUMMARY: The prevalence and incidence of alcoholic liver disease are constantly evolving. Alcoholic liver disease has a wide clinical spectrum. It may progress to cirrhosis and to end-stage liver disease requiring liver transplantation. The histological manifestations range from steatosis without inflammation to liver cell injury and ultimately to fibrosis and cirrhosis. In some cases, the histological manifestation is steatohepatitis, morphological- ly characterized by inflammation and necrosis. Currently, although there are no specific tests to establish a diagnosis of steatohepatitis, some serologi- cal, radiological, or laboratory tests may be useful. Liver biopsy is useful in confirming a suspected diagnosis and in assessing the extent of parenchy- mal damage. This review synthesizes the main aspects of the epidemiology, pathogenesis, morphological characteristics, diagnosis, treatment, and prog- nosis of alcoholic liver disease. CITA: Ann Hepatol. Jan-Mar 2005;4(1):32-42 DOI: 10.1016/S1665-2681(19)32083-6 PMID: 15798662 TÍTULO: Trends in liver disease prevalence in Mexico from 2005 to 2050 through mortality data AUTORES: Méndez-Sánchez N, Villa AR, Chávez-Tapia NC, Poncia- no-Rodriguez G, Almeda-Valdés P, González D, Uribe M. SUMMARY: Background and aims: The epidemiology of liver cirrhosis dif- fers across sex, ethnic groups, and geographic regions. In 2000, chronic liver disease was the fifth leading cause of death in Mexico. Accurate knowl- edge of the demographics of liver disease is essential in formulating health- care policies. Our main aim was to project the trends in liver disease preva- lence in Mexico from 2005 to 2050 based on mortality data. METHODS: Data on national mortality reported for the year 2002 in Mexico were analyzed. Specific-cause mortality rates were calculated for a selected age population (> 25 years old) and classified by sex and projected year (2005-2050). The following codes of the International Classification of Dis- eases for liver diseases were included: non-alcoholic chronic liver disease and cirrhosis, alcoholic liver disease, liver cancer, and acute and chronic hepatitis B and C infection. The projected prevalence of a chronic liver dis- ease was estimated using the following equation: P = (ID x T) / [(ID xT) + 1], where P = prevalence, ID = incidence density (mortality rate multiplied by 2), T = median survival with the disease (= 20 years). RESULTS: Nearly two million cases of chronic liver disease are expected. Alcohol-related liver diseases remain the most important causes of chronic 41

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 15798664 liver disease, accounting for 996,255 cases in 2050. An emergent syndrome PMID: 15844710 is non-alcoholic liver disease, which will be more important that infectious liver diseases (823,366 vs 46,992 expected cases, respectively). Hepatocel- PMID: 16010247 lular carcinoma will be the third leading cause of liver disease. CONCLUSIONS: Chronic liver disease will be an important cause of morbid- ity and mortality in the future. Preventive strategies are necessary, particu- larly those related to obesity and alcohol consumption, to avoid catastrophic consequences. CITA: Ann Hepatol. Jan-Mar 2005;4(1):52-5 DOI: 10.1016/S1665-2681(19)32086-1 TÍTULO: Hepatic angiosarcoma AUTORES: Méndez-Sánchez N, Roldán-Valadéz E, Motola-Kuba D, Al- meda-Valdés P, Uribe M. SUMMARY: Ann Hepatol. Jan-Mar 2005;4(1):60-1 CITA: 10.1016/S1665-2681(19)32088-5 TÍTULO: Prevalence of hepatitis C infection in a population of asymptomatic people in a checkup unit in Mexico city AUTORES: Méndez-Sánchez N, Ponciano-Rodriguez G, Chávez-Tapia NC, Motola-Kuba D, Almeda-Valdes P, Sánchez-Lara K, Ramos MH, Uribe M. SUMMARY: Hepatitis C virus (HCV) infection has an estimated prevalence of 3% around the world. Unfortunately, many persons with HCV infection are asymptomatic. The aim of this study was to determine the prevalence of hep- atitis C Virus infection in asymptomatic persons. This study was carried out in a population-based cross-sectional study in the Checkup Unit of Universi- ty Hospital in Mexico City. Patients with two or more HCV risk factors were studied. Serum specimens from all patients were screened for HCV RNA by qualitative polymerase chain reaction (PCR). HCV RNA-positive serum was also screened by quantitative PCR and for HCV genotype. Three hundred asymptomatic people were included, 194 men and 106 women, with a mean age of 46.8+/-11.9. Six (2%) of the 300 people were positive and viremic. The most common risk factors in positive patients were manicures or pedicures with a nonpersonal instrument and more than three sexual partners. We con- cluded that hepatitis C is frequent in asymptomatic people, and those people are often viremic. In addition, this study suggests that the spectrum of liver disease in asymptomatic and newly diagnosed HCV-positive persons is broad. CITA: Dig Dis Sci. 2005 Apr;50(4):733-7 DOI: 10.1007/s10620-005-2565-1 TÍTULO: Images in hepatology. Hepatoblastoma AUTORES: Pichardo-Bahena R, Méndez-Sánchez N. SUMMARY: Case report CITA: Ann Hepatol. Apr-Jun 2005;4(2):131 42

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 16089354 TÍTULO: Effects of leptin on biliary lipids: potential consequences for gall- stone formation and therapy in obesity AUTORES: Méndez-Sánchez N, Ponciano-Rodrigoez G, Chavez-Tapia N, Uribe M. SUMMARY: Gallstone disease is exceptionally common, occurring especial- ly in Western populations, with cholesterol gallstones predominating. Cur- rently, it is believed that obesity is the most consistent and important risk fac- tor for the development of cholesterol gallstones. Obesity has been shown to be associated with the supersaturation of bile with cholesterol because of increased hepatic secretion of the sterol. In accord with current information from experimental studies, leptin appears to be involved in biliary cholesterol secretion and cholesterol gallstone formation in humans. This review sum- marizes the current information on the role of obesity in biliary lipid secretion as well as the effect of leptin and its potential consequences for gallstone formation and therapy in the obese. CITA: Curr Drug Targets Immune Endocr Metabol Disord. 2005 Jun;5(2):203-8 DOI: 10.2174/1568008054064896 PMID: 16177658 TÍTULO: Hepatobiliary diseases in patients with human immunodeficiency virus (HIV) treated with non highly active anti-retroviral therapy: frequency and clinical manifestations AUTORES: Lizardi-Cervera J, Soto Ramírez LE, Poo JL, Uribe M. OBJECTIVE: To evaluate the frequency of hepatobiliary diseases and the clinical manifestations in patients with HIV treated with non highly active an- ti-retroviral therapy. METHODS: Seven hundred clinical records of patients with HIV infection who entered the Instituto Nacional de Ciencias Médicas y de la Nutrición Salvador Zubirán from January 1987 to December 1996 were reviewed. All patients with alterations associated to hepatobiliary disease and/or liver function tests derangement throughout the clinical development of their dis- ease were included. Demographic variables, date of diagnosis and clinical stage of the disease, as well as the presentation forms, diagnostic approach and image studies were analyzed. RESULTS: One hundred and sixty-one patients (22.8%) with hepatobiliary manifestations were found. The average time between the HIV diagnosis and the presentation of hepatic manifestations was 2-12 years. The majority of patients 124/161 (77%) did not show clinical signs of liver damage. The diagnostic suspicion was established by the presence of alkaline phospha- tase above normal in 29% and alkaline phosphatase plus aminotransferas- es above normal in 45%. Hepatomegaly and jaundice were present in 18% and 4% of the patients, respectively. The most frequent ultrasonographic diagnosis were hepatomegaly (40%) and steatosis (30%). Liver biopsies were performed in 85 (51%) of the patients. The main histologic diagnoses were granulomatous hepatitis (29%), steatosis plus granulomatous hepatitis (19.5%), and steatosis alone (14.6%). Microorganisms were isolated in 27.9% being the most frequent Mycobacterium tuberculosis (26.6%), Histoplasma capsulatum (20%), Cytomegalovirus (13.3%), and Mycobacterium avium in- tracellulare (11%). The HBsAg was positive in 21 of the 69 patients (30.4%). 43

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 16177661 CONCLUSIONS: The clinical presentation was asymptomatic in most of cases and the main etiology could be explained by the presence of associat- ed infections, granulomatoses and liver steatosis. CITA: Ann Hepatol. Jul-Sep 2005;4(3):188-91 DOI: 10.1016/S1665-2681(19)32064-2 TÍTULO: Budd-Chiari syndrome AUTORES: Méndez-Sánchez N, Chávez-Tapia NC, López-Méndez E, Uribe M. SUMMARY: Case report CITA: Ann Hepatol. Jul-Sep 2005;4(3):204 PMID: 16177662 TÍTULO: Hepatic manifestations of Epstein-Barr viral infection PMID: 16184632 AUTORES: Méndez-Sánchez N, Aguilar-Domínguez C, Chávez-Tapia NC, Uribe M. SUMMARY: Little information exists in the international scientific or medical literature about the hepatic manifestations and complications of Epstein-Barr virus (EBV). The aim of this study was to describe a series of patients with hepatic manifestations of EBV infection. Our sample population was a se- ries of patients whose hepatic dysfunction was correlated with a documented EBV infection. Serum concentrations of IgG and IgM antibodies against the EBV viral capsid antigen (anti-EBV VCA IgG), EBV early antigen, and EBV nuclear antigen (EBV-EBNA), and heterophilic antibodies were determined. The expression of latent membrane protein (LMP 1) was also evaluated in each patient. RESULTS: The study included nine patients (six men, three women) with a mean age of 43.5 years. Five patients presented with recent clinical pictures suggestive of acute EBV infection. Five patients began with a cholestatic pattern. Two patients required liver biopsies. Those liver biopsies showed positive immunohistochemical staining for LPM 1. No fatalities were attribut- ed to EBV infection. In conclusion, the bilirubin levels of patients with acute EBV infection differed from those reported in the medical literature. EBV in- fection should be considered in the differential diagnosis of patients with liver abnormalities or diverse hepatic manifestations, increased levels of amino- transferases, or a transitory cholestatic pattern with a favorable outcome. CITA: Ann Hepatol. Jul-Sep 2005;4(3):205-9 TÍTULO: Hepatocyte transplantation for acute and chronic liver diseases AUTORES: Méndez-Sanchez N, Chávez-Tapia NC, Uribe M. SUMMARY: Over three decades of research in experimental animals and several clinical trials have brought us to the threshold of hepatocyte trans- plantation for the treatment of acute and chronic liver disease, and inherited metabolic disorders. However, more extensive clinical studies and routine clinical application are hampered by the shortage of good quality of donor cells. To overcome these hurdles, current research has focused on the search 44

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 16273647 for alternatives, such as liver progenitors, fetal hepatoblasts, embryonic, bone PMID: 16294814 marrow or umbilical cord blood stem cells and conditionally immortalized he- patocytes. Cross-species hepatocyte transplantation is also being explored. It is hoped that ongoing research will permit the application of hepatocyte transplantation to the treatment of a wide array of liver diseases. CITA: Ann Hepatol. Jul-Sep 2005;4(3):212-5 TÍTULO: Serum leptin levels and insulin resistance are associated with gall- stone disease in overweight subjects AUTORES: Méndez-Sánchez N, Bermejo-Martínez LB, Viñals Y, Chavez- Tapia NC, Vander Graff I, Ponciano-Rodríguez G, Ramos MH, Uribe M. AIM: To establish an association between the serum leptin levels and the development of gallstone disease (GD). METHODS: We carried out a non-matched case-controlled study in a uni- versity hospital in Mexico City. Two hundred and eighty-seven subjects were included: 97 cases with gallstones and 190 controls. Body mass index (BMI), fasting plasma leptin, insulin, serum lipid, and lipoprotein levels were mea- sured. Insulin resistance was calculated by homeostasis model assessment (HOMA-IR). Unconditional logistic regression analysis (univariate and multi- variate) stratified by BMI was used to calculate the risk of GD. RESULTS: The multivariate conditional regression analysis revealed a model for those patients with BMI <30. The selected variables in the model were HO- MA-IR index with OR = 1.31, P = 0.02 and leptin higher than median with OR = 2.11, P = 0.05. In the stratum of BMI >=30, we did not find a useful model. CONCLUSION: We concluded that insulin resistance and the development of GD appears to be associated with serum leptin levels in subjects with overweight, but not in obese subjects with similar metabolic profiles. CITA: World J Gastroenterol. 2005 Oct 21;11(39):6182-7 DOI: 10.3748/wjg.v11.i39.6182 TÍTULO: [Impact of the intra-aortic balloon pump in the mortality due to car- diogenic shock secondary to acute myocardial infarction] AUTORES: Arias EA, González-Chon O, García-López SM, Chacón MA, Noriega-Iriondo F, Vega RE, Chávez-Tapia NC. OBJECTIVE: To determine the impact of the intra-aortic balloon pump in the mortality due to cardiogenic shock post-acute myocardial infarction. METHODS: In a two-year period, 292 patients with acute myocardial infarc- tion were admitted to the coronary intensive care unit, 40 were included in the study. Afterwards, patients were divided in two groups: early cardiogenic and late cardiogenic shock, and they were assigned randomly and blind to treatment with inotropics and inotropics plus intra-aortic balloon pump. RESULTS: There were significant differences in the measurements of pul- monary wedge pressure (20.4 +/- 1.6 vs 24.4 +/- 1.50, p = 0.0004) and the cardiac index (2.06 +/- 0.7 vs 1.65 +/- 0.18, p = 0.0002) between the two groups. The late cardiogenic shock group showed an increased mortality (25.9% vs 61.5%, p < 0.05). Patients treated with inotropics + balloon, in 45

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR both early and late shock groups, showed a reduction in mortality of 66% and 69%, respectively. CONCLUSIONS: The use of the intra-aortic balloon pump in the treatment of cardiogenic shock post acute myocardial infarction reduces the mortality when associated with the use of inotropics and reperfusion. CITA: Arch Cardiol Mex. Jul-Sep 2005;75(3):260-6 PMID: 16366178 TÍTULO: [Levosimendan: a new strategy in the treatment of heart failure] PMID: 16381504 AUTORES: González-Chon O, García López SM, Chacón Mercado MA, Arias Sánchez EA, Vega Zapata RE. SUMMARY: Congestive heart failure is a long standing health issue. Tradi- tionally, heart failure has been treated with a wide array of drugs such as di- uretics, digitalis, catecholamine and non catecholamine inotropics, although treatment with these drugs bears adverse effects, such as the generation of arrhythmia and even death. A new class of drugs has recently exerted a positive impact on the treatment of patients with heart failure; these are the calcium sensitizers that enhance myocardial contractility without increas- ing cytosolic calcium. Levosimendan is a calcium sensitizer that, besides increasing contractility, has a vasodilating effect due to the activation of K(ATP) channels, being both mechanisms responsible for an advantageous therapeutic option. Different studies have proven the efficiency and safety profile of the drug on various scenarios and populations; thereby considering levosimendan a real and safe alternative treatment for patients with acute or chronic ventricular failure that need intravenous pharmacological support. CITA: Arch Cardiol Mex. Jul-Sep 2005;75 Suppl 3:S3-130-9 TÍTULO: [Leptine participation in the development of liver steatosis and biliar lithiasis] AUTORES: Méndez-Sánchez N, Ponciano-Rodríguez G, Chávez-Tapia NC, Uribe M. SUMMARY: Obesity increases significantly the risk of developing sever- al common gastrointestinal diseases such as gallstone disease (GD) and hepatic steatosis (HS). Elsewhere we have shown a relationship between HDL cholesterol, cholesterol saturation index, and leptin in obese patients loosing weight. Furthermore, leptin plays an important role facilitating HS and possibly in the associated inflammatory process. The aim of this study was to investigate the relationship between GD and HS. The sample was comprised by patients attending the unit for check-up. Subjects with visible stones or HS by ultrasound (cases) were compared with healthy controls. Demographic and body mass index (BMI) were recorded. Plasma leptin, in- sulin and serum lipids and lipoproteins levels were measured by standard methods. A total of 317 subjects were included in this study. They were di- vided in four groups as follows: GD (n=100), HS (n=84), GD + HS (n=33) and controls (n=100). The control group was significantly older (GD, 52.6+/- 11.6; HS, 49.8+/-11.1; GD +HS, 51.6+/-10.5; 57.1+/-7.4), p< 0.05. BMI was higher in the HS groups (28.7 +/- 2.8) and GD +EH (29.0 +/- 3.8) than in the GD (27.4 +/- 4.3) and control (27.0 +/- 3.1) group, p<0.05. The GD group displayed the highest leptin levels (13.7 241 8.1), P < 0.05, whereas insulin 46

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 16432489 levels were similar in all groups. Since GD and HS subjects have high plas- ma leptin levels compared with controls, our results suggest that leptin plays PMID: 17471867 an important role in the pathophysiology of GD and HS. CITA: Gac Med Mex. Nov-Dec 2005;141(6):495-9 2006 TÍTULO: The endocannabinoid system in chronic liver disease AUTORES: Zamora-Valdés D, Ponciano-Rodríguez G, Chávez-Tapia NC, Méndez-Sánchez N. SUMMARY: Despite the public concern about the controversial use and abuse of marijuana, the scientific community has focused on the therapeutic potentials of cannabinoid compounds and had highlighted the importance of endocannabinoids and their receptors in physiology and disease. Endocan- nabinoids have been shown to be important mediators in neuroendocrine and psychiatric processes such as food intake, drug reward and energy me- tabolism. Cannabinoid receptors are expressed by several cell lines in the liver, such as hepatocytes, myofibroblastic cells, endothelial cells and prob- ably cholangiocytes. A perpetuating role in liver damage for the endocanna- binoid system has been proposed in several steps of chronic liver disease progression. Being a major cause of death worldwide, chronic liver disease is an important problem. New therapies are needed in order to stop or slow damage progression. This review summarizes the results of experimental studies involving the endocannabinoid system in liver disease and their clini- cal and therapeutical implications in hepatology. CITA: Ann Hepatol. Oct-Dec 2005;4(4):248-54 DOI: 10.1016/S1665-2681(19)32047-2 TÍTULO: [Lithiasic cholecystitis: do we have real non-surgical options?] AUTORES: Méndez-Sánchez N, Chávez-Tapia NC, Zamora-Valdés D. SUMMARY: Review article CITA: Rev Gastroenterol Mex. 2005 Nov;70 Suppl 3:73-5 PMID: 16531960 TÍTULO: Hepatocellular carcinoma. An overview AUTORES: Motola-Kuba D, Zamora-Valdés D, Uribe M, Méndez-Sánchez N. SUMMARY: Hepatocellular carcinoma is a common malignancy affecting approximately one million people around the world every year. The inci- dence is low in the occidental world and high in locations such as Southeast Asia and sub-Saharan Africa. Hepatocellular carcinoma primarily affects old people, reaching its highest prevalence among those aged 65 to 69 years old. Chronic infection by the hepatitis B virus is the most common cause of this disease. Other important causes are cirrhosis, chronic viral hepatitis (hepatitis C virus, and hepatitis B plus D viruses), alcohol abuse, obesity, hemochromatosis, alfa1-antitripsin deficiency, and toxins similar to aflatoxin. 47

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 16531967 In most cases, hepatocellular carcinoma is asymptomatic and has a low life expectancy. This article presents a review of the most important epidemio- PMID: 16548293 logical, diagnostic and treatment data about this disease. PMID: 16718795 CITA: Ann Hepatol. Jan-Mar 2006;5(1):16-24 DOI: 10.1016/S1665-2681(19)32034-4 TÍTULO: A 57 year old man with chronic renal failure and cardiac tamponade who developed ischemic hepatitis AUTORES: López-Méndez E, López-Méndez E, López-Méndez I, Her- nández-Reyes P, Galindo-Uribe J, Angulo-Ramírez V, Avila-Escobe- do L, Uribe M. SUMMARY: Ischemic hepatitis is an infrequent entity, usually associated with low cardiac out put. We present a case of a 57 year-old man with chron- ic renal failure and cardiac tamponade who developed elevation of serum alanine transferase level of 5,054 U/L, aspartate transferase level of 8,747 U/L and lactate dehydrogenasa level of 15,220 U/L. The patient developed hepatic encephalopathy and hypoglycemia. Liver Doppler ultrasound was normal. He was seronegative for HBV and HCV, drugs list was scrutinized for the names of known hepatotoxins. Ischemic hepatitis was diagnosed. The hypoglycemia and encephalopathy were solved and the patient was discharged with normal transaminase levels. Ischemic hepatitis is typical- ly preceded by hypotension, hypoxemia, or both. As one would expect, the most common cause of sustained systemic hypotension is cardiovascular disease. Liver biopsy is usually not necessary. The best treatment is support measures and correct the underlying condition. CITA: Ann Hepatol. Jan-Mar 2006;5(1):50-2 DOI: 10.1016/S1665-2681(19)32041-1 TÍTULO: [Ghrelin and the gastro-hypothalamic axis] AUTORES: Méndez-Sánchez N, Chávez-Tapia NC, Uribe-Esquivel M. SUMMARY: Obesity is currently considered one of the most important dis- eases worldwide due to its high morbidity and mortality rates. The mech- anisms involved in the control of satiation, body weight and energy ex- penditure has led to the discovery of new hormones that participate in the gastrichypothalamic axis in charge of regulating satiation and other obesi- ty-related processes. Ghrelin a novel hormone secreted mainly by gastric tissue, has shed some light on this mechanism. It is a hormone that regu- lates satiation and body weight by centrally mediated mechanisms, involving neuropeptide Y and Agouti associated proteins. The present review focuses on some important physiological aspects of this hormone. CITA: Gac Med Mex. Jan-Feb 2006;142(1):49-58 TÍTULO: Low serum levels of ghrelin are associated with gallstone disease AUTORES: Mendez-Sanchez N, Ponciano-Rodriguez G, Bermejo-Marti- nez L, Villa AR, Chavez-Tapia NC, Zamora-Valdes D, Pichardo-Bahena R, Barredo-Prieto B, Uribe-Ramos MH, Ramos MH, Baptista-Gonzalez HA, Uribe M. 48

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR PMID: 16787375 AIM: To explore the role of ghrelin in gallstone disease. METHODS: We carried out a cross-sectional study in 150 subjects, 38 with gallstones (cases) and 112 controls. We also did a real-time PCR-RT study in twenty gallbladder samples each. Body mass index (BMI), serum insu- lin, ghrelin, and serum lipids were measured. Logistic regression analyses (univariate and multivariate) were conducted to estimate the probability of gallstone disease associated with serum ghrelin concentrations. RESULTS: Cases were statistically different from controls in gender distribu- tion (P = 0.01), age (53 vs 44 yr, P = 0.002), BMI (28 vs 25; P = 0.004), and glucose (5.26 vs 4.98 mmol/L; P = 0.05). The prevalence of ghrelin serum lev- els above the third tercile was lower in subjects without metabolic syndrome (P < 0.05). In a multivariate model, we found a protective effect, when ghrelin values were higher than the median value (OR = 0.27, 95%CI 0.09-0.82, P = 0.02). Twenty (20%) gallbladder specimens expressed ghrelin mRNA. CONCLUSION: Serum ghrelin concentrations are associated with a protec- tive effect of GD. CITA: World J Gastroenterol. 2006 May 21;12(19):3096-100 DOI: 10.3748/wjg.v12.i19.3096 TÍTULO: Adiponectin, structure, function and pathophysiological implica- tions in non-alcoholic fatty liver disease AUTORES: Méndez-Sánchez N, Chavez-Tapia NC, Zamora-Valdés D, Uribe M. SUMMARY: Obesity is a major risk factor for the development of the meta- bolic syndrome, a cluster of diseases including insulin resistance, type 2 di- abetes, dyslipidemia, hypertension, microalbuminuria, atherosclerosis, and non-alcoholic steatohepatitis. On the other hand, it is now generally accept- ed that adipose tissue acts as an endocrine organ producing a number of substances with an important role in the regulation of food intake, energy ex- penditure and a series of metabolic processes. Adiponectin is a recently dis- covered hormone produced exclusively by adipocytes. In fact, adiponectin is considered currently as a major factor in obesity-related insulin resistance and atherosclerosis. This new hormone differs from other adipocytokines in that its production and concentrations are actually decreased in insulin resis- tant subjects. The aim of this review is to summarize the current knowledge about the chemistry and physiology of adiponectin and to discuss its implica- tions in the pathophysiology and potential treatment of insulin resistance and non-alcoholic fatty liver disease. CITA: Mini Rev Med Chem. 2006 Jun;6(6):651-6 DOI: 10.2174/138955706777435689 PMID: 16807515 TÍTULO: Obesity-related leptin receptor polymorphisms and gallstones disease AUTORES: Méndez-Sánchez N, Bermejo-Martínez L, Chávez-Tapia NC, Zamora-Valdés D, Sánchez-Lara K, Uribe-Ramos MH, Ponciano-Rodrí- guez G, Baptista-González HA, Ramos MH, Uribe M. 49

RESÚMENES DE ARTÍCULOS PUBLICADOS POR MÉDICOS E INVESTIGADORES DE MÉDICA SUR OBJECTIVE: Investigate the association between polymorphisms in the leptin receptor gene associated with obesity and gallstone disease. DESIGN: We conducted a cross-sectional study, carried out at a tertiary setting. SUBJECTS: We enrolled 97 subjects, comprising 54 subjects with gall- stones (cases) and 43 controls (without gallstones). MEASUREMENTS: Diet was assessed using a validated questionnaire for the Mexican population. Body mass index, waist circumference, serum glu- cose, insulin, leptin, lipids and lipoproteins levels were measured. Insulin resistance was calculated by HOMA-IR. Genomic DNA was isolated from lymphoblastoid cells, and Q223R and K656N polymorphisms in the leptin receptor gene were typed using polymerase chain reaction. Unconditional univariate logistic regression analysis was conducted to estimate the proba- bility of gallstone disease associated with the polymorphisms as main effect. RESULTS: Cases were different in gender (40.74% males in cases vs 74.41% in controls; p < 0.001), older (49.74 vs 44.83 years; p < 0.05), and had more body fat (32.34% vs 28.14%; p = 0.01). Individuals carrying the polymorphism Q223R exhibited a higher BMI (28.44 +/- 6.6 kg/m2 vs 25.94 +/- 3.67 kg/m2, p < 0.05) and waist circumference (96.7 +/- 16.39 cm vs 89.2 +/- 11.05 cm, p < 0.05). In univariate analysis, we did not observe a relation between the presence of a R223 or N656 genotype and gallstone disease in our population (OR = 0.78, 95% CI 0.35-1.73). CONCLUSION: Obesity-related leptin receptor polymorphisms are not asso- ciated with gallstones disease. CITA: Ann Hepatol. Apr-Jun 2006;5(2):97-102 DOI: 10.1016/S1665-2681(19)32025-3 PMID: 16937532 TÍTULO: Smoking is not associated with nonalcoholic fatty liver disease AUTORES: Chavez-Tapia NC, Lizardi-Cervera J, Perez-Bautista O, Ra- mos-Ostos MH, Uribe M. AIM: To analyze the relationship between smoking and nonalcoholic fatty liver disease (NAFLD). METHODS: This is a cross-sectional study of a healthy population, carried out in a check-up unit of a university hospital in Mexico City. We enrolled 933 subjects, 368 current smokers (cases) and 565 persons who had never smoked (controls). Demographic, metabolic and biochemical variables were measured in the two groups. NAFLD was determined by ultrasound and met- abolic syndrome according to ATPIII. RESULTS: A total of 548 men (205 cases and 343 controls) and 337 women (114 cases and 223 controls) were included in the analysis. Statistical differ- ences between cases and controls were observed only in high blood pres- sure prevalence (6.6% vs 11.3%, P < 0.05; cases and controls respectively), high-density lipoproteins (1.00 +/- 0.26 vs 1.06 +/- 0.28 mmol/L, P < 0.005), triglycerides (2.18 +/- 1.49 vs 1.84 +/- 1.1 mmol/L, P < 0.001), and erythro- cyte sedimentation rate (11.3 +/- 9.3 vs 13.5 +/- 11.9 mm/h, P < 0.001). No differences were observed in the prevalence of NAFLD (22.27% vs 29.68%, P = NS) and metabolic syndrome (41.69% vs 36.74%, P = NS). Univariate 50