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Biomedical subjects

M A Simón

Publications and source records attributed to M A Simón.

At least 19 recordsLinked to original sources
PubMed2006

TGFB1 gene polymorphisms: their relevance in the susceptibility to Helicobacter pylori-related diseases.

Recent studies have revealed elevated expression of transforming growth factor beta1 (TGF-beta1) in gastric mucosa of patients with gastric cancer (GC) and those undergoing ulcer repair. As production of TGF-beta1 is genetically regulated, we aimed to assess whether functional polymorphisms of the TGFB1 gene are involved in susceptibility to and clinical characteristics of Helicobacter pylori-related diseases. DNA from 142 unrelated Spanish patients with GC, 200 with peptic ulcer and 342 healthy controls was typed for the MspA1I T+869C, and the Sau96I G+915C polymorphisms of the TGFB1 gene using polymerase chain reaction and RFLP analysis. H. pylori infection and CagA/VacA antibody status were determined by Western blot in patients and controls. H. pylori infection (odds ratio (OR): 11.44; 95% confidence interval (CI): 4.45-29.42; P<0.001) and non-steroidal anti-inflammatory drugs (OR: 5.07; 95% CI: 2.53-10.16; P<0.001) were identified as independent risks factors for duodenal ulcer (DU), whereas the TGFB1+869(*)C/C genotype was associated with reduced risk of developing the disease (OR: 0.32; 95% CI=0.15-0.68; P=0.003). Our results show that the TGFB1 T+869C gene polymorphism is involved in the susceptibility to DU and provide further evidence that host genetic factors play a key role in the pathogenesis of H. pylori-related diseases.

Aged↗
PubMed2003

Phobic anxiety in 11 nations. Part I: Dimensional constancy of the five-factor model.

The Fear Survey Schedule-III (FSS-III) was administered to a total of 5491 students in Australia, East Germany, Great Britain, Greece, Guatemala, Hungary, Italy, Japan, Spain, Sweden, and Venezuela, and submitted to the multiple group method of confirmatory analysis (MGM) in order to determine the cross-national dimensional constancy of the five-factor model of self-assessed fears originally established in Dutch, British, and Canadian samples. The model comprises fears of bodily injury-illness-death, agoraphobic fears, social fears, fears of sexual and aggressive scenes, and harmless animals fears. Close correspondence between the factors was demonstrated across national samples. In each country, the corresponding scales were internally consistent, were intercorrelated at magnitudes comparable to those yielded in the original samples, and yielded (in 93% of the total number of 55 comparisons) sex differences in line with the usual finding (higher scores for females). In each country, the relatively largest sex differences were obtained on harmless animals fears. The organization of self-assessed fears is sufficiently similar across nations to warrant the use of the same weight matrix (scoring key) for the FSS-III in the different countries and to make cross-national comparisons feasible. This opens the way to further studies that attempt to predict (on an a priori basis) cross-national variations in fear levels with dimensions of national cultures.

Adolescent↗
PubMed2001

An emerging role for interferon in haemophiliacs with chronic hepatitis C?

The combination of interferon (IFN) and ribavirin is the current gold standard for treatment of chronic hepatitis C virus (HCV) infection with sustained remission rates of 35--40% being achieved in haemophilic patients. A similar beneficial effect of this combined therapy has been suggested even for patients with compensated liver cirrhosis and some authors have reported a possible role for IFN and ribavirin in the prevention or delay in the development of hepatocellular carcinoma (HCC), a well known complication of HCV infection in haemophiliacs. The absence, due to design difficulties, of definite randomized controlled clinical trials remains a handicap for the routine use of specific therapy of HCV infected patients with the aim of preventing HCC. A discussion of these important issues has been performed in this paper.

Antiviral Agents↗
PubMed2001

Successful outcome of a cirrhotic patient with postoperative haematuria treated with a single high dose of recombinant factor VIIa.

Recombinant factor VIIa (rfVIIa) has been widely used for the treatment and prevention of bleeding episodes in haemophiliacs with high-titre inhibitors. High single doses are the treatment of choice for joint and muscle bleeds in those patients. There are only a few reports on the value of rfVIIa in cirrhotic patients with haemostatic impairment but this drug can consistently correct the prothrombin time in these individuals. We report a case of a good response to a single high dose of rfVIIa in a patient with advanced liver disease who suffered from severe refractory postoperative haematuria.

Factor VII↗
PubMed2001

Experimental ivermectin treatment of sarcoptic mange and establishment of a mange-free population of Spanish ibex.

Ivermectin was used to treat sarcoptic mange in Spanish ibex (Capra pyrenaica hispanica). Its therapeutic effectiveness was analyzed when it was administered through subcutaneous injection, to sick animals in the consolidation stage of mange (third phase) and, with double injections to chronically affected animals (fourth phase) at a dosage of 0.2 or 0.4 mg/kg body weight (bw). Three wk after treatment, the animals in the third phase of mange treated with a high dose (0.4 mg/kg bw) of ivermectin were completely cured. The same result was achieved after 4 wk of treatment in those animals in phase 3 of mange when 0.2 mg/kg body weight was used. Double injection with ivermectin, even at high doses, did not guarantee the complete cure of all cases of sarcoptic mange in the chronic stage (phase 4); only three of six animals were free of Sarcoptes scabiei. The second experiment consisted on the application of a sanitation program in order to obtain a population of Spanish ibex free from S. scabiei, starting with free-ranging animals, some of them healthy and others sick. After capture the animals were classified as chronically ill, in which case they were excluded from the program, mite carriers and healthy specimens. All the animals were treated first topically with foxim (500 mg/l) and subcutaneously with ivermectin (0.4 mg/kg bw). The infected animals were housed in the treatment pen, and received two doses of ivermectin (0.2 mg/kg bw) at an interval of 15 days, then spent 15 days in the quarantine pen, where they received a further dose before they were included in the pool of healthy animals, and immediately were placed in the quarantine phase. The sanitation we implemented was fully effective in curing the affliction of Spanish ibex affected by S. scabiei.

Animals↗
PubMed2000

[Cost-effectiveness analysis of 2 strategies of Helicobacter pylori eradication: results of a prospective and randomized study in primary care].

BACKGROUND: To analyze cost-effectiveness of two different strategies to treat H. pylori infection in peptic ulcer in the primary care setting. PATIENTS AND METHODS: Consecutive patients with endoscopic diagnosis of peptic ulcer were randomized to one of two strategies: a) treatment during 7 days with omeprazole, tetracycline, metronidazole and bismuth subcitrate ("quadruple" therapy) and if failure second-line treatment with omeprazole, amoxycillin and clarithromycin during 7 days (OCA7), and b) initial treatment with OCA7 and if failure treatment with "quadruple therapy". End point was eradication 8 weeks after last treatment dose. Direct and indirect costs were estimated (euros, 1997) and a cost-effectiveness analysis using a decision-tree model was undertaken after real clinical data. 95% confidence intervals are given. RESULTS: After screening 255 patients, 97 were finally included. 48 patients were given strategy a and 49 strategy b. Eradication was obtained (intention-to-treat) in 72.9% (CI 95%: 58.2-84.7) in group a versus 91.8% (CI 95%: 80.4-97.7) (p < 0.05) in group b. Mean cost per case treated was lower in group a (237 versus 268 euros) but cost per case eradicated was lower in group b (320 versus 296 euros). The cost was primarily determined by efficacy. CONCLUSIONS: Treatment with OCA7 followed by rescue with "quadruple" therapy if failure is more efficient in our area that the inverse strategy. Efficiency is mostly determined by efficacy.

Adolescent↗
PubMed1999

Quadruple therapy is effective for eradicating Helicobacter pylori after failure of triple proton-pump inhibitor-based therapy: a detailed, prospective analysis of 21 consecutive cases.

BACKGROUND: Data regarding the effectiveness of second-line treatment of Helicobacter pylori infection are limited, especially if microbiological studies are considered. METHODS AND PATIENTS: We conducted a prospective, uncontrolled study of a consecutive series of 21 peptic ulcer patients with failure of 1-week lansoprazole, amoxicillin, and clarithromycin. H. pylori status was evaluated by urease test, histology, culture, and urea breath test. Susceptibility to amoxicillin, clarithromycin, and metronidazole was studied by E-test. Cure of infection was defined as negative results from endoscopy-based tests 1 month after treatment and negative results from a urea breath test at 2 months. Treatment consisted of a 1-week combination of lansoprazole (30 mg bid), tetracycline (500 mg qid), metronidazole (500 mg tid), and bismuth subcitrate (120 mg qid). RESULTS: H. pylori was resistant to metronidazole in three cases, to clarithromycin in three cases, and to both clarithromycin and metroinidazole in an additional three patients. No resistance to amoxicillin was found. Eradication was obtained in 20 cases (95.2% confidence interval [CI], 76.2-99.9). The only patient in whom infection was not eradicated harbored a metronidazole-resistant (minimum inhibitory concentration > 32 micrograms/ml) strain. No significant side effects were reported. CONCLUSION: Quadruple therapy obtains a high eradication rate even in patients with clarithromycin- and metronidazole-resistant strains. Further randomized and controlled studies are warranted and are urgently needed.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1999

Sarcoptic mange in Spanish ibex from Spain.

The Spanish ibex (Capra pyrenaica hispanica) population of the "Sierras de Cazorla, Segura y Las Villas" Nature Park (Spain) was isolated as the result of a severe epidemic of sarcoptic mange. In this context, the dynamic characteristics of the disease were analyzed in a wild group consisting of 35 animals from the beginning of the epizootic (when the mating period started) to the extinction of the population due to mange. Monthly tracking permitted the sequential characterization of the pathology in each animal. The duration of the disease was 2 to 3 mo, evolving to severe disease and terminating in death. Incidence and prevalence rates in terms of morbidity and severity, and mortality and lethality were calculated. At the end of the mating season, 81% of the population were affected. There were no statistically significant differences in severity of the disease across sex or age categories of the animals. Most of the carcasses were found in caves used as refuge and/or near rivers or streams. Additionally, 46 of the 63 (73%) ibex captured in different areas of the nature park were naturally infected with the Sarcoptes scabiei. Infected ibex were examined for number of mites during the initial stage of the disease (n = 3), in the development stage (n = 12), in the consolidation stage (n = 17), and in the chronic stage (n = 14). The prevalence of mites in different anatomical regions was determined in each of these phases of the infection. A histological study of the skin lesions was conducted in 22 animals. Both the clinical and the pathological (macroscopic and microscopic) aspects of the sarcoptic mange in Spanish ibex corresponded to the classic description of sarcoptic mange in other wild and domestic small ruminants.

Age Factors↗
PubMed1998

[Effectiveness of the eradication of Helicobacter pylori by treatment with omeprazol, amoxicillin, and clarithromycin according to dosage and administration schedule].

BACKGROUND: There are many reports that evaluate the efficacy of the combination of omeprazole, amoxicillin and clarithromycin in the eradication of Helicobacter pylori, but data about effectivity in clinical practice are sparse. The goal of our study is to evaluate the effectivity in the clinical setting of this combination with diverse durations and doses. METHODS: This is a retrospective analysis of 187 patients (128 male and 59 female), with an endoscopic diagnosis of duodenal ulcer (156), gastric ulcer (25) and both (6) with Helicobacter pylori infection as defined by both: a positive ureasa test and histology. After diagnosis the patient were treated with one of three combinations: a) omeprazole: 20 mg/12 h + amoxicillin: 1 g/12 h + clarithromycin: 500 mg/12 h, during 6 days (n = 60); b) omeprazole: 20 mg/12 h + amoxicillin: 1 g/12 h + clarithromycin: 500 mg/12 h, during 7 days (n = 74), and c) omeprazole: 20 mg/12 h + amoxicillin: 1 g/8 h + clarithromycin: 500 mg/8 h, during 7 days (n = 53). After the 6 or 7 day treatment period the patients did not receive any further treatment until a follow-up control unit. Eradication was evaluated with one of two tests: endoscopy (with ureasa test and at least 4 histologic samples) (n = 90) or urea breath test according to european protocol (n = 97). RESULTS: No patient dropped out because of side effects and compliance was above 80% in all cases. The global eradication rate was 87.2% (CI 95%: 82.4-92%). According to treatment the rate were respectively 80% (CI 95%: 67.7-89.2%) with scheme A; 89.2% (CI 95%: 79.8-95.2%) with scheme B, and 92.5% (CI 95%: 81.8-97.9%) with scheme C, with no statistically significant differences among groups. Difference between schemes and C, however, was almost reached (p = 0.053). CONCLUSIONS: The combination of omeprazole, amoxicillin and clarithromycin at standard doses (scheme B) is effective in clinical practice. Higher dose of amoxicillin and clarithromycin does not improve the results, and shorter duration of therapy associated with lower, although not significant rate of eradication.

Adult↗
PubMed1994

[Omeprazole and cimetidine in the treatment of upper digestive hemorrhage].

AIM: To compare the efficacy of omeprazole (40 mgs/12 h i.v.) and cimetidine (1,200 mgs/i.v./day) in the management of upper gastrointestinal bleeding. EXPERIMENTAL DESIGN: Randomized, prospective open clinical trial. The end points are: mortality, surgical requirements, transfusion requirements, and length of hospitalization in Bleeding Unit and Hospital. PATIENTS: We study patients with upper gastrointestinal bleeding from peptic sources (duodenal ulcer, gastriculcer, acute gastric erosions and peptic esophagitis). 462 patients are evaluated and 282 finally included. RESULTS: 151 patients were given cimetidine and 131 omeprazole. No significant differences in any of the end points were found. CONCLUSIONS: The use of omeprazole does not improve cimetidine efficacy in the entire group of patients with upper gastrointestinal bleeding.

Cimetidine↗
PubMed1994

[The endoscopic management of postoperative biliary fistulae].

We report a series of 15 patients with a postoperative biliary fistula treated by endoscopic sphincterotomy. The exact location of the bile leak was revealed by ERCP in 13 cases (87%): cystic duct remnant in 6 (39%), intrahepatic biliary tree in 4 (26%), and main bile duct in 3 (20%). In all cases a distal obstacle (ie: retained stones, hydatid material) to bile flow was also found in ERCP. Treatment consisted of endoscopic sphincterotomy and subsequent removal of the distal obstacle, and could be completed in 13 (87%) cases. In our experience the treatment of postoperative biliary fistula with a distal obstruction bile flow by endoscopic sphincterotomy is a safe and effective procedure, and should be recommended as the first option in those patients.

Adult↗
PubMed1993

Identification of glucagon receptors in human adipocytes from a liposarcoma.

The presence of glucagon receptors on human adipocytes has not yet been described. In this work we present an exceptional case of glucagon binding to human adipocytes taken from a malignant tumor of adipose tissue of a patient with a liposarcoma. Binding analysis revealed that the total number of glucagon receptors on liposarcoma-cells was 99,000 and the apparent receptor affinity (ED:50) was 5 x 10(-9) M. Despite the presence of these specific receptors, glucagon was unable to induce a lipolytic response, or to activate the adenylate-cyclase system in these liposarcoma-cells. Whether the induction of glucagon receptors is a specific process of the tumor biology remains to be elucidated.

Adipose Tissue↗
PubMed1992

[Changes in the mechanism of action of insulin on fatty tissue accumulations in lipomas, Madelung's lipomatosis and liposarcoma].

In this paper, the preliminary results regarding the alterations of the biological action mechanism of insulin in several types of pathological accumulations of fat, i.e. lipomas, Madelung's Lipomatosis and liposarcoma, are presented. The results indicate significant alterations both at the insulin receptor and post-receptor levels, with reduced biological activity of this hormone, which could have and inductive role in the pathogenesis of such entities.

Adipose Tissue↗
PubMed1991

Clinical usefulness of polymorphonuclear elastase in predicting the severity of acute pancreatitis: results of a multicentre study.

The usefulness and clinical applicability of quantitative plasma polymorphonuclear elastase determinations in the diagnosis of the severity of acute pancreatitis was analysed in a multicentre study and was compared with the usual prognostic systems of Ranson and Osborne et al. The study comprised 182 patients, 154 with a mild episode of acute pancreatitis and 28 with a severe episode, defined by the development of major complications or a fatal outcome. In the severe cases neutrophilic elastase reached significantly higher values than in mild cases (P less than 0.001) by the time the patient was admitted (2-12 h after the onset of the disease), reflecting considerable leucocyte activation. The sensitivity and specificity of this test are therefore greater than 90 per cent, with a positive severity predictive value of almost 80 per cent at the time of admission and 97 per cent after 24 h, and a negative predictive value of approximately 98 per cent. In addition to requiring 48 h for evaluation, the usual prognostic systems show a sensitivity of 77-85 per cent, a specificity of 70-77 per cent, a positive predictive value of 40-48 per cent, and a negative predictive value of 92-95 per cent, clearly lower than those obtained with leucocyte elastase. Polymorphonuclear elastase is therefore a very early and reliable marker in the diagnosis of the severity of acute pancreatitis, in addition to being easily adaptable to the routine of any hospital laboratory.

Acute Disease↗
PubMed1991

Abnormal sympathetic and renal response to sodium restriction in compensated cirrhosis.

It has been proposed that in liver cirrhosis portal hypertension causes splanchnic vasodilation and this induces blood volume expansion to maintain blood pressure. The current study was designed to explore the homeostatic response to sodium restriction, a maneuver aiming to contract blood volume, in compensated cirrhosis. Mean blood pressure, sympathetic nervous activity, and proximal sodium reabsorption were evaluated in 16 healthy control and 21 nonazotemic cirrhotic patients (11 without ascites and 10 with ascites) under two experimental conditions: after 4 days on a free sodium diet (basal condition) and after 4 days on a restricted sodium diet (40 mmol/day). No differences were observed in basal conditions in the above parameters between control and cirrhotic patients without ascites. However, cirrhotic patients with ascites showed lower basal values of mean blood pressure and higher basal levels of both plasma norepinephrine and fractional proximal sodium reabsorption than controls. Neither control nor cirrhotic patients with ascites showed significant changes in the measured parameters after sodium restriction. In contrast, in nonascitic patients, this maneuver induced an elevation in plasma norepinephrine concentration (164.4 +/- 24.6 vs. 270.1 +/- 24.9 pg/mL; mean +/- SEM; P less than 0.005) and in fractional proximal sodium reabsorption (86.4 +/- 2.1 vs. 91.8% +/- 0.5%; P less than 0.01). In addition, the nonascitic cirrhotic patients became hypotensive compared with controls (80.9 +/- 1.6 vs. 88.5 +/- 4.8 mm Hg; P less than 0.05) when subjected to the low-sodium diet. In patients without ascites, under conditions of sodium restriction, the decrease in mean arterial pressure correlated inversely with the increase in plasma norepinephrine concentration (r = -0.713; P less than 0.05), whereas the levels of plasma norepinephrine correlated directly with fractional proximal sodium reabsorption (r = 0.893; P less than 0.01). These findings suggest that ineffective circulatory volume is detected in nonascitic cirrhotic patients only under conditions of sodium restriction, but it is always present in cirrhotic patients with ascites, irrespectively of the amount of sodium in the diet. These results are compatible with the existence of fixed arterial vasodilation in cirrhosis.

Adult↗