PubMed Health⌕ Search

Biomedical subjects

R Calpena

Publications and source records attributed to R Calpena.

31 records · Page 2Linked to original sources

Detection of P-glycoprotein in frozen and paraffin-embedded gastric adenocarcinoma tissues using a panel of monoclonal antibodies.

AIMS: Most chemotherapeutic regimens used against gastric carcinoma include anthracyclines whose effectiveness can be impaired by the presence of P-glycoprotein. In order to obtain a reliable pattern of P-glycoprotein expression in these tumours an immunohistochemical study using a panel of anti-P-glycoprotein antibodies was performed in frozen and paraffinized tissues. METHODS AND RESULTS: Frozen and paraffinized samples from 25 gastric carcinomas were immunohistochemically analysed using a panel of four anti-P-glycoprotein monoclonal antibodies including C219, MRK16, JSB-1 and C494. Semiquantitative analysis indicated that moderate or high P-glycoprotein levels were detected in 40% to 76% of gastric adenocarcinomas, depending on the anti-P-glycoprotein antibody used. The antibody C494 was the most sensitive in detecting P-glycoprotein in both frozen and paraffinized gastric carcinoma samples. Moreover, C494 showed a pattern of staining exclusively associated with the plasma membrane, in contrast to the cytoplasmic with reinforcement of plasma membrane pattern displayed by the other three antibodies. Significant differences in P-glycoprotein levels were obtained when C494 and MRK16 were used in frozen tissues. Finally, detection of P-glycoprotein in frozen samples did not improve when compared to paraffinized ones. CONCLUSIONS: It appears that P-glycoprotein is frequently expressed in gastric adenocarcinomas, and the use of C494 complemented by JSB-1 is recommended for reliable detection of P-glycoprotein in this neoplasm.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Failure to detect early recurrence of gastric cancer.

Early gastric cancer recurrence is sometimes difficult to diagnose even by protocols using imaging techniques and tumor markers. We report a gastric cancer recurrence diagnosed by the appearance of a Sister Mary Joseph's nodule that illustrates the lack of sensitivity of these methods. We also discuss the protocol we currently follow for these patients.

Anastomosis, Roux-en-Y↗

Canine pancreatic responses to intracolonic perfused nutrients.

To study the effect intracolonic perfusion of nutrients has on exocrine pancreatic secretion, six dogs were prepared with gastric, duodenal, and cecal cannulas using a modified Thomas technique. In our study protocol, we collected pancreatic juice by selective ductal cannulation after having applied several types of intracolonic stimulation: perfusion of sodium chloride, tryptophan, rice starch + glucose, or sodium oleate. All these solutions were applied together with a background dose of intravenous secretin. Our results showed a significant increase in the volume of pancreatic juice and bicarbonate output after intracolonic perfusion of sodium oleate. Other perfusions did not change these parameters. Protein output did not change in any of the cases. It seems that the ascending colon plays a regulating role in pancreatic secretion; in some conditions the colon could increase exocrine pancreatic function.

Animals↗

Influence of type of dietary fat (olive and sunflower oil) upon gastric acid secretion and release of gastrin, somatostatin, and peptide YY in man.

The effects of adaptation to two diets differing in the type of dietary fat on the gastric acid secretory response to food and on the circulating levels of gastrin, somatostatin and peptide YY (PYY) were examined in humans. The study involved 18 cholecystectomized subjects previously submitted to a 30-day adaptation period to diets containing olive (group O) or sunflower oil (group S) as the fat source. During the experiments, physiological stimulation was achieved by ingestion of 200 ml of oleic acid- (group O) or linoleic acid-enriched (group S) liquid mixed meals. These resulted in an immediate rise in gastric pH. In group S, the return to the premeal value was completed within 60 min, and a further decline to values significantly lower than the basal ones was observed at the end of the study period. In contrast, ingestion of the meal containing olive oil attenuated and prolonged the pH decrease after the meal, this being associated with the suppression of postprandial gastrin response. Food ingestion induced no significant changes in plasma somatostatin concentration in either group, and no significant differences were revealed between them during the basal or postprandial situations. Plasma PYY levels were consistently higher in group O throughout the entire study period, although significance was reached only at resting. In conclusion, our results show that a 30-day adaptation period to diets containing olive oil as the main source of dietary fat results, compared with those containing sunflower oil, in an attenuated gastric secretory function in response to a liquid meal in humans. The effects of olive oil were associated with a suppression of serum gastrin and higher levels of PYY.

Adult↗

Pancreatic enzyme secretion in response to test meals differing in the quality of dietary fat (olive and sunflowerseed oils) in human subjects.

The aim of the present study was to investigate in human subjects whether or not the ingestion of two liquid meals that differed only in their fatty acid composition (due to the addition of olive oil (group O) or sunflowerseed oil (group S) as the source of dietary fat) would lead to differences in the pancreatic enzyme activities secreted into the duodenum. The experiments were performed in eighteen cholecystectomized subjects who, during the 30 d period immediately before surgery, modified their habitual diets in such a way that their fat composition would reflect, as far as possible, that of the experimental meals. Lipase (EC 3.1.1.3), colipase, amylase (EC 3.2.1.1), chymotrypsin (EC 3.4.21.1) and trypsin (EC 3.4.21.4) activities were measured in duodenal contents aspirated before and after the ingestion of the test meals. The plasma levels of secretin and cholecystokinin (CCK) were also examined. Duodenal enzyme activities were similar in resting conditions. No significant differences were revealed in postprandial enzyme activities, except for lipase activity, which was higher in group O, probably in relation to the greater plasma CCK concentrations observed in this group. In the absence of enzyme output data, we should not exclude the possibility that the type of dietary fat will affect human pancreatic enzyme secretion to a greater extent than is evident from the present study, for instance through a flow-mediated effect, as we previously observed in dogs.

Amylases↗

Follow-up of patients resected for gastric cancer.

In this study we used a cost-outcome analysis to evaluate our follow-up protocol for patients who had been resected for gastric cancer. We designed a descriptive cross-sectional trial through consecutive sampling of patients who had undergone resection of gastric carcinoma and were followed in our outpatient department during 1991. Serological (CEA) and or imaging procedures were pathologic at least two months prior to the onset of symptoms in 33% of recurrences. No significant correlation was found between serum CEA levels and CEA tumor tissue staining in patients who recurred. Only 17% of patients who relapsed underwent further treatment (surgery and chemotherapy) with no improvement found in terms of survival. The overall cost per year has been estimated at US$ 6118. Our results show that serological levels of CEA and available imaging techniques for routine follow-up provide little advantage in diagnosing gastric cancer recurrence over clinical surveillance alone.

Adenocarcinoma↗

Gastric carcinoma: study of the most eminent prognostic factors.

In order to analyse some prognostic factors in relation to gastric cancer, 218 patients were included in a prospective protocol at 'Hospital General de Elche' (Spain) with a follow-up of 100%. Survival curves were calculated using Kaplan-Meier analysis and compared using the log-rank test. The number of patients who underwent resection was 122 (63.5%). In 70 cases (36.5%) the resection was not possible. The postoperative mortality was 4.9%. In the survival of patients with gastric cancer we find the following prognostic factors are significant: age, tumour site, macroscopic type, depth of gastric wall affection, presence of lymph nodes, staging, resectability and surgical intention (curative vs palliative).

Adult↗

[Metabolic disorders in the gastrectomized patient].

The present study attempts on one hand to study the metabolic disorders which may present themselves in the gastrectomized patient, such as the malabsorption of fat, vitamin B12, folic acid and iron as well as the possible correlation between steatorrhea and the presence of exocrine pancreatic insufficiency. For this purpose a group of 71 patients have been studied who have undergone a subtotal gastrectomy (70.42%) or total (29.58%) in the General Surgery Services of Elche. The results obtained show the presence of ferropenic or megaloblastic anemia in 61.97% of the group, serious steatorrhea in only 3 patients (4.22%) and calciumphosphorous metabolism alterations appeared in 21.13%. With this we conclude that anemia is the most frequent ferropenic alteration in the gastrectomy patient; steatorrhea does not seem to be produced exclusively by the presence of exocrine pancreatic insufficiency and bone alterations in the gastrectomized patient appear in an insidious manner, being more a question of biochemical alterations than actual clinical lesions.

Adult↗

[Manometric factors associated with recurrence in botulinum toxin treatment for chronic anal fissure].

INTRODUCTION AND AIM: To evaluate the effectiveness of botulinum toxin in the treatment of chronic anal fissure after long-term follow-up and establish the manometric factors related to recurrence. PATIENTS AND METHOD: We performed a prospective study in 50 consecutive patients with chronic anal fissure who were treated with 25 U botulinum toxin injected into the internal sphincter. Clinical and manometric parameters were recorded until the fourth year of follow-up. RESULTS: There was a tendency to progressive recurrence over time (54% at 4 years) associated with manometric factors indicating hyperexcitability of the internal anal sphincter (persistently elevated mean resting pressure, percentage of time with slow waves, and number of patients or percentage of time with ultra-slow waves after treatment). CONCLUSIONS: Treatment of chronic anal fissure with botulinum toxin leads to long-term cure in less than 50% of patients. In patients with manometric factors related to recurrence, this treatment is insufficient for definitive cure.

Adult↗

[Postoperative enteral nutrition with a high content of mono- and polyunsaturated fatty acids].

We have done a clinical study in patients with benign biliary disease and indication for surgery, with the aim of analyzing some parameters of gastric secretion, biliary and pancreatic function, and gastrointestinal hormones in relation to the quantity and quality of the dietary fat (monounsaturated and polyunsaturated fatty acids), acting on the postoperative enteral ingestion, modifying the lipid source by its elaboration. In the present work we show the results derived from the analysis of the gastric and duodenal juices in relation to the type of fat administered, with a global description of the study being necessary. The studied sample consisted of 20 patients diagnosed with simple gallstones, who were divided into two groups (n = 10) according to the usual ingestion of fats: olive oil (Olive Group) or sunflower oil (Sunflower Group). A control group (n = 10) has also been considered, without taking into account their dietary habits. The patients were subjected to surgery, and after the immediate postoperative period they were fed, orally, with an enteral diet prepared with commercially available formulae (modular EDA); as a lipid source we have added olive oil, rich in monounsaturated fatty acids, for the Olive Group, and sunflower oil, rich in polyunsaturated oil, for the Sunflower Group. In the control group cream was added as lipid source (mono and polyunsaturated fatty acids). The caloric value of the diet is calculated based on the caloric value of its components (protein: 17%, carbohydrate: 53%, lipid 30%). The daily caloric requirements are determined based on the daily basal metabolism, according to the Harris-Benedick formula.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗

[The use of the Dreimlich probe for obtaining samples in a postoperative study of biliopancreatic function in cholecystectomized patients].

We have performed a clinical study involving patients with symptomatic gallstones and indications for surgery, to analyze the biliary and pancreatic response to the quality of dietary fat (degree of unsaturation). As part of the investigative method, we have designed a clinical protocol adapted to the needs of the study, in this respect, we have used gastrointestinal intubation to obtain independent samples of gastric and duodenal juices, by means of a long nasoduodenal tube or a modified Dreimlich tube, placed manually in the intraoperative period, during the cholecystectomy. The characteristics of the tube are such that its manipulation is difficult, which led to situations postoperatively and during sampling, which may alter or invalidate the obtained drainage material. In the present study we define the protocol and the phases of the investigation, and we reflect on the usefulness of the Dreimlich tube as a method, analyzing its advantages and disadvantages.

Biliary Tract↗