[Retrospective study of 50 ileostomies at the Salvador Zubirán National Institute of Nutrition]. / Estudio retrospectivo de 50 ileostomías en el Instituto Nacional de la Nutrición Salvador Zubirán.

OBJECTIVES: To establish the diseases that motivated an ileostomy and the short and long-term morbi-mortality of the procedure. METHODS: Retrospective analysis of 50 consecutive cases of ileostomies performed from 1989-1993 at a referral center in Mexico City. RESULTS: Most ileostomies were temporary (92%); the most frequent diagnoses were multiple familial polyposis, inflammatory bowel disease, and diverse intra-abdominal inflammatory complications. Operative mortality was 22%, caused mainly by the severity of the disease that motivated the ileostomy. A reoperation was required in 14% of the cases because of stomal complications (stricture, prolapse); 6% presented peristomal dermatitis, 4% high output, and 4% associated depression. With a mean time interval of three months, 32 patients were subjected to intestinal reconnection with a morbidity of 19% but no mortality. CONCLUSIONS: Ileostomy remains a necessary procedure mainly on a temporary basis. It is convenient to prevent complications by means of adequate surgical techniques, and a better rehabilitation by a multidisciplinary team.

Congenital hypertrophy of the retinal pigment epithelium associated with familial adenomatous polyposis.

PURPOSE: Multiple, bilateral areas of congenital hypertrophy of the retinal pigment epithelium (CHRPE) have been described in association with familial adenomatous polyposis (FAP). Histopathologic findings have suggested a generalized effect of the FAP gene on the RPE, which could impair the functional integrity of the RPE. The clinical, psychophysical, electrophysiologic, and fluorescein angiographic findings in CHRPE in subjects with FAP were assessed. METHODS: RPE function was assessed in 7 subjects with CHRPE and a family history of FAP. Four had documented FAP (mean age = 22.25 years) and the other three were siblings of affected subjects, with a 50% risk of developing FAP (mean age = 6.33 years). All subjects underwent comprehensive ophthalmologic examination. RESULTS: All subjects showed mild hyperopia (mean, +1.13 D; best corrected visual acuity, 20/20 or better). On perimetry, there were scotomas corresponding to some lesions. ERG showed normal rod, maximal, single-flash cone, and flicker responses. Light-dark ratio was within the normal range on EOG. Fluorescein angiography demonstrated normal retinal vasculature overlying the CHRPE lesions, which blocked background choroidal fluorescence. A normal choriocapillaris was observed through some hypopigmented lacuna. CONCLUSION: CHRPE has been related to generalized expression of an abnormal gene in RPE, but its functional abnormalities tend to be localized.

[Molecular genetics of colorectal cancer and carcinogenesis]. / Genética molecular del cáncer colorectal y carcinogénesis.

Genetic and environmental aspects play an important role in the development of colorectal cancer. However, the common molecular alteration in both hereditary and sporadic colon cancer is localized in the APC gene. the APC gene maps in the long arm of chromosome 5 and was discovered in patients with familial adenomatous polyposis (FAP). The search for the APC gene led to the identification of restriction fragment length polymorphisms (RFLPs) in FAP patients. Using these RFLPs in relatives of FAP patients it is possible to make the presymptomatic and prenatal diagnosis. The FAP syndrome is an interesting model of carcinogenesis in vivo. Thus the different stages involved in the FAP syndrome which include hyperproliferative epithelium, adenoma, adenocarcinoma and metastases, have allowed the analysis of molecular alterations in oncogenes and tumor suppressor genes. The APC gene alteration if not inherited, occurs as the earliest molecular alteration in the development of colorectal cancer whereas structural alterations of the genes myc, ras, p53, MCC and DCC are considered to be late events. All these investigations have lead to 1) a better understanding of the ethiology of cancer and 2) early diagnosis of colorectal cancer in both the hereditary and sporadic forms of the disease.

[New strategies in the clinical evaluation of patients with colon cancer based on molecular studies]. / Nuevas estrategias en la evaluación clínica de pacientes con cáncer de colon con base en estudios moleculares.

During the last five years molecular studies allowed important advances in the knowledge of cancer colon with important clinical implications. The main finding was the identification and sequence analysis of the APC gen. Structural alterations of this gene have been detected in patients with Familial Adenomatous Polyposis and Gardner syndrome, which suggest a common disease. Furthermore, alterations of the APC gen appears to be also altered in cases of cancer of colon sporadic. Indicating that structural alteration of the APC gen can be inherited and/or acquired. Restriction fragment-length polymorphisms in the chromosome 5q21-22 can now be used clinically for premorbid diagnosis and counseling in familial adenomatous polyposis. The molecular studies allow the clinician to have a new approach in the management and screening of families with familial adenomatous polyposis. The sequence analysis and specific identification of the structural alteration of the APC gene is a more expensive and sophisticated study, although represent a more direct approach. In the Department of Gastroenterology of the INNSZ we are performing such molecular studies. The main purpose of our group is to proportionate integral clinical-molecular studies for families with hereditary colon cancer, create a national register of these diseases and investigate the molecular bases in order to generate new molecular diagnosis tools.

[The recurrence of duodenal ulcer in patients undergoing treatment with ranitidine and placebo. A multicenter study]. / Recurrencia de la úlcera duodenal en pacientes sometidos a tratamiento con ranitidina y placebo. Estudio multicéntrico.

This randomised, double-blind multicenter study was conducted in order to evaluate the long-term effect (one year) of 150 mg ranitidine vs placebo in 51 patients with healed duodenal ulcer. Seventeen patients had ulcer recurrence at the end of follow-up, one among the 24 patients that received ranitidine and 16 among the 27 patients that received placebo (p = 0.00009). No side effects was detected. Our results support the usefulness of a one-year maintenance therapy with 150 mg ranitidine.

[The biological behavior of colorectal carcinoma in young patients]. / Comportamiento biológico del carcinoma colorrectal en pacientes jóvenes.

Patients of the Instituto Nacional de la Nutrición Salvador Zubirán under 40 years of age with colorectal carcinoma were compared with similar patients above 40 in a retrospective and longitudinal study. Patterns of presentation, stage at diagnosis, degree of tumor differentiation and survival were analyzed. Abdominal pain, rectal bleeding and weight loss were the most frequent clinical manifestations in both groups. Constipation was more common in the young adults (60.5% vs 34.2%; p less than 0.05). In both groups, rectosigmoid was the most frequent location of the neoplasm. Cecal carcinoma was found in 2.6% of patients under 40 years and in 11.8% (p less than 0.05) in older patients. There was a higher frequency of mucinous tumors in the young patients (26% vs 13%; p = NS). Colon cancer in both groups were in advanced stage at presentation. The survival rate for young adults was 30%, and 21% for the other group (p = NS). The degree of tumor differentiation did not affect survival in both groups. Dukes stage was the only prognostic factor identified. The need for early recognition of colorectal cancer in young adults is emphasized by the greater incidence of advanced disease and poor prognosis.

[A 10-year prolective study on cancer of the digestive system]. / Estudio prolectivo de 10 años de cáncer del aparato digestivo.

OBJECTIVE: A ten year prolective and multicentre study of cancer of the Digestive Tract aims to evaluate the variations on frequency and to identify risk factors. METHODS: Ten hospitals are participating five in Mexico City and five in other states. Data were obtained through the hospitals files and specially designed questionnaires, the latter mainly diet and habits oriented. RESULTS: Through this ten years in the 4,715 cases studied we can appreciate a decreasing tendency of the carcinoma of the stomach (GC) that has been the most frequent until 1984 in the general group General Hospital and Instituto Nacional de la Nutrición. Since then and up to date, first place in frequency in shared between the stomach and colorectal carcinoma (CRC). CRC has been increasing even in the General Hospital in which GC was very high. Eighth years ago we found that people in those hospitals in which GC was high the diet was poor in proteins, fat A and C vitamin. People in those hospitals with high frequency of CRC had diet high in protein, fat and low in fiber. A new study on diet is ongoing. Gallbladder and biliary tract carcinoma has been increasing in all the hospitals. A high O blood group was found in the Juarez Hospital in which gallbladder carcinoma was the highest. O group is highest in the indian people. Cancer of the gallbladder is very high in Pimas and Navajos indians. A plan to study litogenic index and culture of salmonella is going to be practiced in bile from normal and gallbladder carcinoma. Concerning habits, tobacco and alcohol consumption are most frequent in cancer of the esophagus and pancreas. Also coffee consumption is high in the latter. CONCLUSIONS: Along this 10-year study, the frequency of gastric cancer has been decreasing. Instead, the frequencies of colo rectal and biliary tract cancers have been increasing. Variations in frequencies correlated with the composition of the diet, fiber consumption habits and racial characteristics of the different groups.

[Ethics in clinical research. World Medical Association]. / Etica en la investigación clínica. Asociación Médica Mundial.

Ethics is the branch of Philosophy that treats the essential; the origin and the obligatory character of the moral, for that reason it relates with the man conscience; it deals with the knowledge and acceptation of the right and the rejection of the evil (wrong). This is subordinated to the will of the man who is free to decide between the right and the evil. The purpose of biomedical research involving human subjects must help to improve diagnostic, therapeutic and prophylactic procedures and to understand the aetiology and pathogenesis of a disease. In current medical practice most diagnostic, therapeutic or prophylactic procedures involve hazard. This applies especially to biomedical research. Medical progress is based on research which ultimately must rely in part on experimentation involving human subjects. The World Medical Association has prepared the recommendations described in this article as a guide to every physician in biomedical research involving human subjects.

[Smoking, consumption of alcoholic beverages and coffee as factors associated with the development of cancer of the pancreas]. / Tabaquismo, consumo de bebidas alcohólicas y café como factores asociados al desarrollo de cáncer de páncreas.

The purpose of this study was to evaluate retrospectively the role of alcohol intake, smoking and coffee consumption as risk factors in the development of cancer of the pancreas. Twenty nine cases with pancreatic cancer and 29 controls matched by sex, socioeconomic status and age were evaluated. Information on alcohol, tobacco and coffee consumption was obtained by specially designed questionnaires. Odds ratios were calculated and analyzed by chi square testing. The combination of the 3 factors gave an odds ratio of 26.3, whereas alcohol and coffee consumption gave an odds ratio of 13.9. Considered independently, only alcohol and coffee consumption were found to be significantly associated with cancer of the pancreas.

The pharmacokinetic characteristics of a hepatobiliary 99mTc-radiopharmaceutical: comparison of the imported and national kits.

In nuclear medicine, the search for the perfect hepatobiliary agent started in 1955 with the rose bengal dye labeled with 131I. With the advent of technetium-99m, many ligands were labeled and Tc-99m-PG and 99mTc-HIDA were among the best suited for this purpose. Both were synthesized at the radiopharmacy laboratory during 1977-1980 and have been used at INNSZ for clinical studies. For the last three years, a new ligand with a bromine atom and an extra methyl radical has been reported as being one of the best third generation HIDAs. We received the gift of several kits of trimethyl-Br-IDA from Sorin Biomedica, Italy, (A) and of Mebrofenin from ININ, Mexico, (B) to be labeled and tested in order to select one of them for clinical work. For a comparative study on the radiopharmacodynamic characteristics of the two labeled ligands, six healthy women volunteered to undergo two tests with a 72 hour hour rest period to assure complete washout. After the I.V. dose of 111 MBq (3 mCi) the dynamic study was started and a total of 127 16-second images were acquired with a Siemens Digitrac 750 scintillation camera coupled to a Scintiview computer. Static images were taken at the end of the dynamic study and after breakfast. Blood and urine samples were collected for 24 hours and the amount of radioactivity was measured with a well type scintillation detector. The radiopharmacokinetic results are listed in tables 1-4.(ABSTRACT TRUNCATED AT 250 WORDS)

Famotidine in the short and long-term treatment of duodenal ulcer.

Famotidine was compared to ranitidine in a short-term study on the treatment of duodenal ulcer. Famotidine 20 mg. b.i.d., 40 mg. b.i.d. and 40 mg. nocte heal as many ulcer as ranitidine (90.9%, 91.7%, 83.3% and 100% respectively). A single 20 mg. bedtime dose shows to be effective on preventing ulcer recurrence for as long as 48 weeks; the 38% recurrence rate observed with famotidine was statistically different from the 78% observed with placebo. Diarrhoea was the most common complain observed during the short-term trial, followed by sleepiness and headache. The few and small biochemical alterations during the long-term treatment (increase in transaminases, alkaline phosphatase, glucose, BUN) could in no instance be directly related to the substances on use.

Famotidine in the short and long-term treatment of duodenal ulcer.

Famotidine was compared to ranitidine in a short-term study on the treatment of duodenal ulcer. Famotidine 20 mg. b.i.d., 40 mg. b.i.d. and 40 mg. nocte heal as many ulcer as ranitidine (90.9

, 91.7

, 83.3

and 100

respectively). A single 20 mg. bedtime dose shows to be effective on preventing ulcer recurrence for as long as 48 weeks; the 38

recurrence rate observed with famotidine was statistically different from the 78

observed with placebo. Diarrhoea was the most common complain observed during the short-term trial, followed by sleepiness and headache. The few and small biochemical alterations during the long-term treatment (increase in transaminases, alkaline phosphatase, glucose, BUN) could in no instance be directly related to the substances on use.

Tratamiento de la úlcera duodenal con dosis únicas nocturnas de 800 mg de cimetidina durante cuatro semanas / Treatment of duodenal ulcer with cimetidine with single night doses of 800 mg during 4 weeks

Se realizó un estudio de investigación clínica, de diseño abierto para el investigador y ciego para el endoscopista, que incluyó a 34 pacientes con úlcera duodenal aguda confirmada mediante endoscopia. Los pacientes recibieron cimetidina en dosis de 800 mg por vía bucal, al momento de acostarse, durante cuatro semanas; al finalizar el periodo de tratamiento se realizó nuevamente endoscopia y se observó cicatrización en 25 de los 34 pacientes (74% ). Se logró rápido mejoramiento del dolor, tanto diurno como nocturno, especialmente del dolor intenso, con cero episodios a la cuarta semana de tratamiento. La dosis empleada, además de lograr una atingencia de 100% por parte del pacientes, no causó efecto indeseable alguno atribuible al medicamento