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J A Fernández-Represa

Publications and source records attributed to J A Fernández-Represa.

10 recordsLinked to original sources
PubMed2002

[The phospholipase A2 inhibitor, aristolochic acid, inhibits chloride secretion without altering barrier function].

AIM: To study the effect of aristolochic acid (AA) and the effect of phospholipase A2 (PLA2) on barrier function and electrogenic chloride secretion in intestinal epithelium. MATERIAL AND METHODS: Electrophysiological studies were performed in the T84 cell line and rat distal colon. Ionic secretion and transepithelial resistance were determined. RESULTS: Exogenous AA increased calcium-stimulated secretion in the T84 cell line. Incubation of rat distal colon in the presence of AA, a PLA2 inhibitor, reduced basal ionic secretion without affecting transepithelial resistance and inhibited ionic secretion stimulated by a cyclic adenosine monophosphate (AMPc) agonist, forskolin. In T84 cells, AA inhibited both carbachol- and forskolin-stimulated secretion. CONCLUSION: PLA2 modulates electrogenic chloride secretion but has no effect on barrier function in the T84 cell line or in rat distal colon.

Animals↗
PubMed2002

Peptide YY secretion in morbidly obese patients before and after vertical banded gastroplasty.

BACKGROUND: The Peptide YY (PYY) secretion pattern was assessed in morbidly obese (MO) patients before and after vertical banded gastroplasty (VBG). METHODS: 12 MO patients (10 women, 2 men) age 29-62 years, BMI 50.7 +/- 9.6 kg/m2, treated with a VBG were studied. Before surgery, blood samples were taken in basal conditions of fasting and 10, 15, 20, 30 and 60 min after the ingestion of a semiliquid test meal. This was repeated in the same patients 6 and 12 months after VBG. Blood samples were also taken from 6 healthy non-obese subjects as controls. PYY plasma concentration was measured by radioimmunoassay with I125. RESULTS: There were statistically significant differences between the preoperative PYY concentration in MO patients compared to controls. After a VBG, PYY concentration varied significantly compared to the preoperative levels. There was no significant difference between the PYY concentrations in the MO patients after VBG and the controls. CONCLUSION: PYY concentration is lower in MO patients compared with non-obese. After VBG, PYY concentration gradually rises to the control levels.

Adult↗
PubMed1999

Open biliary tract surgery: multivariate analysis of factors affecting mortality.

BACKGROUND/AIM: The overall mortality rate in patients undergoing supraduodenal choledochotomy for benign biliary tract disease is around 3%. The aim of this study is to identify and quantify factors affecting the mortality in a group of patients undergoing open common bile duct exploration for benign biliary disease. METHODS: Patients (n = 158) who underwent common bile duct exploration during a 5-year period in a teaching hospital were retrospectively reviewed. RESULTS: Univariate and multivariate statistical analyses were performed. The former identified four statistically significant variables: age (p < 0.001), acute cholangitis on admission (p < 0. 001), heart disease (p < 0.05), and a dilated common bile duct on preoperative ultrasound scan (p < 0.05). Multivariate analysis identified three variables which independently increased operative mortality: age (p = 0.05), heart disease (p = 0.03), and cholangitis (p = 0.008). The latter was associated with the greatest operative mortality, since it increased almost eight times the risk to die after surgical intervention. CONCLUSION: We conclude that an adequate perioperative cardiovascular management may be important in order to improve surgical outcome. Appropriate antibiotic prophylaxis and subsequent treatment after routine operative bile cultures may reduce septic complications and mortality. Finally, an alternative procedure, such as endoscopic sphincterotomy, may be indicated in high-risk patients in order to drain the common bile duct preoperatively and to decrease the risk of unresponsive biliary sepsis.

Acute Disease↗
PubMed1998

[Chloride secretion in the intestinal epithelium: channels, ions, and intracellular signaling].

Salt and water secretion by epithelial cells is required to hydrate the mucosal surface of both gastrointestinal and respiratory tracts. Intestinal secretion is the result of active transcellular chloride transport by epithelial cells lining the crypts. Defective chloride secretion is responsible for many common disorders such as secretory diarrhea and cystic fibrosis. In this review we deal with the most relevant issues regarding epithelial transcellular chloride secretion. We first consider the principles of membrane transport and transport protein function. Then, we briefly discuss the use of state-of-the-art techniques for electrophysiological studies such as "patch-clamp" and microfluorometry. The epithelial chloride secretion model is described according to observations made in both native tissue and cultured intestinal epithelial cells. Next, we consider the intracellular signaling cascades involved in the regulation of membrane transport systems and transcellular chloride secretion. Finally, the clinical implications of the most recent findings are commented, with emphasis on potential molecular targets for the treatment of cystic fibrosis and secretory diarrhea.

Cell Membrane↗
PubMed1998

[Intestinal pneumatosis].

Intestinal pneumatosis is an infrequent disease of difficult clinical and radiologic diagnosis. It may be accompanied by pneumoperitoneum in up to 30% of the cases leading to differential diagnosis with pictures of visceral perforation. We herein present 4 cases of intestinal pneumatosis in whom pneumoperitoneum was associated in 3 patients. Diagnosis was intraoperative in 2 patients submitted to emergency surgery because of an associated acute gastrointestinal event (intestinal volvulus and acute cholecystitis). The other 2 cases were diagnosed by computerized tomography and colonoscopy, respectively, and given their satisfactory clinical evolution they received conservative treatment. The course of the disease was favorable in all the patients with the radiologic signs of pneumatosis disappearing.

Aged↗
PubMed1997

Complications of laparoscopic cholecystectomy in the ageing patient.

AIM: to determine the safety of simple laparoscopic cholecystectomy in ageing patients. METHOD: the outcome of patients between 60 and 70 years of age and patients over 70 who underwent laparoscopic cholecystectomy for symptomatic non-malignant gallbladder disease was comparatively analysed. All patients over 60 years of age with symptomatic gallbladder disease and without cholecholithiasis, septic shock, diffuse peritonitis, gallbladder malignancy, portal hypertension or contraindication for general anaesthesia were selected for simple laparoscopic cholecystectomy (n = 158). This group represents over 80% of all elderly patients undergoing biliary surgery at our department over this period. Group A (n = 97) included patients from 60 to 69 years of age. Group B (n = 61) comprised patients over 70 years. RESULTS: there was no difference in sex distribution between groups. Operative time and conversion rates were similar in both groups. The overall morbidity rate was 14.5%, with no statistically significant increase in group B (11% for group A vs 20% for group B). No perioperative mortality occurred. Recurrent biliary surgery was required in two patients from group B (3%). Postoperative endoscopic retrograde cholangiography and sphincterotomy was done in four patients from group A (4%). The mean postoperative stay was longer for older patients (group A, 3.1 (2.5) days; group B, 4.2 (4.3) days; P = 0.05). CONCLUSION: simple laparoscopic cholecystectomy is safe in the aged, even for patients over 70. This procedure is associated with a short hospital stay and low rates of re-admission and recurrent biliary surgery.

Adult↗
PubMed1997

[Necrotizing gastroenteritis associated with inflammatory bowel disease].

Gangrene of the stomach is a rare and catastrophic event, usually attributed to local pathologic conditions. Although there are no cases documented in the literature, non-occlusive arterial ischemia is sometimes listed among the causes of necrotizing gastritis. We report a case of necrotizing gastroenteritis associated with a low flow state secondary to an episode of fulminant colitis, fecal peritonitis and septic shock. The patient recovered after staged resection of the involved segments of the gastrointestinal tract.

Adult↗