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M Esteve

Publications and source records attributed to M Esteve.

At least 19 recordsLinked to original sources
PubMed2006

Spectrum of gluten-sensitive enteropathy in first-degree relatives of patients with coeliac disease: clinical relevance of lymphocytic enteritis.

BACKGROUND: Limited data on a short series of patients suggest that lymphocytic enteritis (classically considered as latent coeliac disease) may produce symptoms of malabsorption, although the true prevalence of this situation is unknown. Serological markers of coeliac disease are of little diagnostic value in identifying these patients. AIMS: To evaluate the usefulness of human leucocyte antigen-DQ2 genotyping followed by duodenal biopsy for the detection of gluten-sensitive enteropathy in first-degree relatives of patients with coeliac disease and to assess the clinical relevance of lymphocytic enteritis diagnosed with this screening strategy. PATIENTS AND METHODS: 221 first-degree relatives of 82 DQ2+ patients with coeliac disease were consecutively included. Duodenal biopsy (for histological examination and tissue transglutaminase antibody assay in culture supernatant) was carried out on all DQ2+ relatives. Clinical features, biochemical parameters and bone mineral density were recorded. RESULTS: 130 relatives (58.8%) were DQ2+, showing the following histological stages: 64 (49.2%) Marsh 0; 32 (24.6%) Marsh I; 1 (0.8%) Marsh II; 13 (10.0%) Marsh III; 15.4% refused the biopsy. 49 relatives showed gluten sensitive enteropathy, 46 with histological abnormalities and 3 with Marsh 0 but positive tissue transglutaminase antibody in culture supernatant. Only 17 of 221 relatives had positive serological markers. Differences in the diagnostic yield between the proposed strategy and serology were significant (22.2% v 7.2%, p<0.001). Relatives with Marsh I and Marsh II-III were more often symptomatic (56.3% and 53.8%, respectively) than relatives with normal mucosa (21.1%; p = 0.002). Marsh I relatives had more severe abdominal pain (p = 0.006), severe distension (p = 0.047) and anaemia (p = 0.038) than those with Marsh 0. The prevalence of abnormal bone mineral density was similar in relatives with Marsh I (37%) and Marsh III (44.4%). CONCLUSIONS: The high number of symptomatic patients with lymphocytic enteritis (Marsh I) supports the need for a strategy based on human leucocyte antigen-DQ2 genotyping followed by duodenal biopsy in relatives of patients with coeliac disease and modifies the current concept that villous atrophy is required to prescribe a gluten-free diet.

Adolescent↗
PubMed2006

[Bilateral tension pneumothorax after retrieval of transtracheal jet ventilation catheter].

We report a bilateral tension pneumothorax which occurred in a 36-year-old man after high-frequency jet ventilation (HFJV) for panendoscopy. The patient had been treated with radiotherapy and chemotherapy two years ago for an oropharyngeal adenocarcinoma, and by surgery for a recurrence. The incident occurred after a cough episode triggered by the withdrawal of the Ravussin transtracheal catheter. We are discussing the risk factors and the mechanisms of pneumothorax during HFJV with special emphasis on trapping and lung fibrosis.

Adenocarcinoma↗
PubMed2006

Combined effects of oral oleoyl-estrone and limited food intake on body composition of young overweight male rats.

OBJECTIVE: The combined effects of limited food intake and OE treatment have been analysed in order to determine whether hypocaloric diets enhance the slimming effects of OE on mature overweight male rats. Two levels of dietary limitation at 50 and 25% of a standard intake were established, roughly corresponding to the human LCDs and VLCDs. DESIGN: Wistar male rats (6 weeks old) were made overweight by a cafeteria diet. After transition to standard diet, they were subjected to food restriction: down to 50 or 25% with respect to the transition period. Half the animals were given daily oral gavages of 10 nmol/g oleoyl-estrone (OE), and the rest received only the vehicle during 10 days. MEASUREMENTS: Changes in weight and body composition: water, lipid, protein or gross energy were determined by comparing the final pool size with that of day 0, calculated from the initial body weight and the composition of untreated rats. Energy and nitrogen balances were estimated. Plasma levels of metabolites and hormones were also measured. RESULTS: OE induced changes in body composition similar to those elicited by a 50% reduction in food, with massive loss of lipid and energy. OE-treated rats ate less than the controls, but additional effects on body composition on reduced diet were minimal. OE improved metabolic homoeostasis: better maintained glycaemia, lower cholesterol and shallower hormonal changes, but at the expense of slightly increased protein mobilisation. CONCLUSIONS: The data presented suggest that no advantages are accomplished by combining OE treatment and hypocaloric diets compared with OE alone, at least under the experimental conditions tested, since the effects were not additive. Despite OE affecting food intake, mechanisms other than that are deemed responsible for the mobilisation of body fat, since intake alone cannot explain the effects on body weight, nor the metabolic and hormonal changes in OE-treated rats. It is concluded that the combination of food restriction and OE may result in unwanted increased protein mobilisation with no synergy between both slimming treatments.

Animals↗
PubMed2005

Short-term oral oleoyl-estrone treatment increases plasma cholesterol turnover in the rat.

OBJECTIVE: Oral treatment with oleoyl-estrone induces the loss of body fat and improvement of insulin resistance. Since cholesterol levels are deeply affected by oleoyl-estrone, we investigated here whether short-term treatment affected cholesterol turnover and overall metabolite changes. DESIGN: Wistar female rats received a single oral dose of 10 mumol/kg oleoyl-estrone in 0.2 ml of sunflower oil. Groups of animals were killed at timed intervals and blood samples were taken. In a second experiment series, rats had implanted carotid and jugular cannulas and were given a single gavage of oleoyl-estrone. These rats were used for the measurement of the cholesterol turnover rate. MEASUREMENTS: Body weight change and food intake: Glucose, total and HDL-cholesterol, triacylglycerols, 3-hydroxybutyrate, nonesterified fatty acids, insulin, HOMA score in the rats of the first series. Cholesterol: Cholesterol pool changes and cholesterol turnover rates in the rats of the second series. RESULTS: OE induced early effects, decreasing food intake, cholesterol and HDL-cholesterol levels, and increasing insulin sensitivity (HOMA score). OE also increased cholesteryl-ester turnover, and decreased circulating total cholesterol, especially esterified cholesterol pools. CONCLUSIONS: The role of early changes in insulin sensitivity induced by oral OE cannot explain per se the deep changes in cholesterol handling, essentially a consequence of accelerated lipoprotein turnover. However, the increase in cholesteryl-ester turnover observed with OE treatment may be, at least in part, a consequence of the decrease in insulin resistance. The compounded effect of increased insulin sensitivity and accelerated lipoprotein turnover may help explain the early and marked hypocholesterolaemic effects of OE.

Administration, Oral↗
PubMed2004

Chronic hepatitis B reactivation following infliximab therapy in Crohn's disease patients: need for primary prophylaxis.

BACKGROUND: There is little information about the effect of infliximab on the clinical course of liver disease in Crohn's disease patients with concomitant hepatitis B virus (HBV) infection. Theoretically, immunosuppression induced by infliximab will facilitate viral replication which could be followed by a flare or exacerbation of disease when therapy is discontinued. There are no specific recommendations on surveillance and treatment of HBV before infliximab infusion. Two cases of severe hepatic failure related to infliximab infusions have been described in patients with rheumatic diseases. PATIENTS AND METHODS: Hepatitis markers (C and B) and liver function tests were prospectively determined to 80 Crohn's disease patients requiring infliximab infusion in three hospitals in Spain. RESULTS: Three Crohn's disease patients with chronic HBV infection were identified. Two of the three patients with chronic HBV infection suffered severe reactivation of chronic hepatitis B after withdrawal of infliximab therapy and one died. A third patient, who was treated with lamivudine at the time of infliximab therapy, had no clinical or biochemical worsening of liver disease during or after therapy. From the remaining 80 patients, six received the hepatitis B vaccine. Three patients had antibodies to both hepatitis B surface antigen (anti-HBs) and hepatitis B core protein (anti-HBc) with normal aminotransferase levels, and one patient had positive anti-hepatitis C virus (HCV) antibodies, negative HCV RNA, and normal aminotransferase levels. Except for the patients with chronic HBV infection, no significant changes in hepatic function were detected. CONCLUSIONS: Patients with Crohn's disease who are candidates for infliximab therapy should be tested for hepatitis B serological markers before treatment and considered for prophylaxis of reactivation using antiviral therapy if positive.

Adolescent↗
PubMed2002

Effect of oral oleoyl-estrone on adipose tissue composition in male rats.

OBJECTIVE: To determine whether the oral administration of oleoyl-estrone has similar mass-decreasing effects on the main different sites of white adipose tissue (WAT). DESIGN: Adult male Zucker lean rats were given a daily oral gavage of oleoyl-estrone (OE, 10 micromol/kg) in 0.2 ml of sunflower oil for 10 days, and were compared with controls receiving only the oil. The mass of the main WAT sites: subcutaneous, epididymal, mesenteric, retroperitoneal, gluteal, perirenal and interscapular, as well as perirenal and interscapular brown adipose tissue (BAT), were dissected and studied. MEASUREMENTS: The tissue weight, DNA, protein, lipid and total cholesterol content, together with the levels of leptin and acyl-estrone in the larger WAT and BAT masses, were measured. RESULTS: The weights of WAT depots were correlated with body weight but those of BAT were not. Cell size was maximal for epididymal and mesenteric and minimal for subcutaneous and retroperitoneal WAT and BAT. Differences were detected in DNA, and in protein and lipid content between distinct WAT sites. OE treatment tended to decrease cell number and cell size in WAT; only small differences in composition were found between WAT locations inside the visceral cavity and those outside. Decreases in lipid content were maximal in mesenteric fat. Leptin and acyl-estrone content were fairly uniform at the different WAT sites, except for high concentrations in gluteal WAT. OE induced a greater decrease in leptin and acyl-estrone than in DNA and lipids; changes in these hormones were fairly parallel in all sites. CONCLUSIONS: In general, the differences in composition between visceral and peripheral subcutaneous WAT and their responses to OE were less marked than the individual differences observed between specific sites, regardless of location. WAT sites are fairly diverse in composition, but their response to OE treatment was uniform. OE decreased the weight of WAT through reduction of both cell numbers and size; but did not change the mass or composition of BAT significantly. The effects of OE are more marked in the hormonal signals (leptin and acyl-estrone) from the tissue than in its composition and mass.

Adipose Tissue↗
PubMed2002

Serum selenium and risk of large size colorectal adenomas in a geographical area with a low selenium status.

OBJECTIVE: Selenium is a fundamental nutrient to human health that might have anticarcinogenic effects. Previous studies have assessed the possible relationship of selenium status to colorectal adenomas with controversial results. We primarily aimed to assess the relationship of serum selenium status with the presence of large size colorectal adenomas in subjects living in a poor selenium region. The serum selenium status in colorectal cancer was also evaluated. METHODS: Serum selenium levels were measured in 28 patients with large size sporadic adenomatous polyps, 24 patients with colorectal adenocarcinomas, and 35 age-matched healthy individuals. A logistic regression analysis was performed to assess the relationship of serum selenium to colorectal adenomatous polyps after adjusting for confounding variables (age, sex, smoking habit, and alcohol drinking). RESULTS: Among subjects aged < or = 60 yr, mean serum selenium levels were significantly lower in both patient groups (adenoma, 57.9 +/- 4.3 microg/L; cancer, 43.7 +/- 6.6 microg/L) than in healthy controls (88.9 +/- 8 microg/L) (p = 0.0001). There were no difference among subjects > 60 yr old. A significant inverse association between selenium status and the diagnosis of large size adenomatous polyps after adjusting for confounding variables was found (adjusted p = 0.029). Subjects with higher selenium status (> or = 75th percentile value of 82.11 microg/L) had a lower probability (OR = 0.17, 95% CI = 0.03-0.84) to be in the adenoma group than subjects with lower selenium status (< 82.11 microg/L). This association was more marked in subjects aged < or = 60 yr (adjusted p value = 0.04, OR = 0.08, 95% CI = 0.007-0.91), and was not significant in older subjects. CONCLUSIONS: Results suggest that high selenium status may decrease the risk of large size adenomas in a low selenium region, and that this preventive effect seems to be exclusive to subjects < or = 60 yr. These results will need to be confirmed in additional epidemiological studies before recommending selenium supplementation in patients with colon adenomas.

Adenoma↗
PubMed2002

Hypertransaminasemia in pediatric celiac disease patients and its prevalence as a diagnostic clue.

OBJECTIVES: The aims of this study were to evaluate the following: 1) the prevalence of hypertransaminasemia (HT) in a pediatric celiac disease (CD) and its relation with clinical parameters; 2) the frequency of HT as the only manifestation of pediatric CD; and 3) the evolution of HT after a gluten free diet. METHODS: A total of 114 consecutive pediatric CD patients were studied (60% with classical and 40% with atypical forms). Antiendomisyum antibodies and anti-tissue transglutaminase antibodies were determined in patients with a clinical suspicion of CD (including unexplained chronic HT), in patients at risk, and in patients with preoperative increased ALT activity for minor surgery. CD was confirmed by duodenal biopsy. At baseline, the relationship between clinical factors and aminotransferase status was univariately and multivariately assessed. After starting a gluten free diet, patients were followed up, until serological markers cleared and serum aminotransferase normalized. RESULTS: HT occurred in 32% of patients (37 of 114) at diagnosis. HT was the only manifestation of CD in five patients (4.3%). Patients with HT were younger (2.9 +/- 0.4 yr) than patients with normal aminotransferases (5.1 +/- 0.5 yr) (p = 0.007). A higher percentage of patients with classical CD tend to have abnormal aminotransferases (73%; 95% CI = 65-81%) than do patients with atypical CD (27%; 95% CI = 19-35%) (p = 0.068). Logistic regression analysis showed that only younger age was significantly associated with HT (p = 0.039; OR = 0.8; 95% CI = 0.71-0.99). Aminotransferases normalized with a gluten free diet in all 35 patients who were followed-up, either before (n = 18) or at the same time (n = 17) as serological markers cleared. CONCLUSIONS: HT is a frequent finding in pediatric CD patients and, in a substantial proportion, may be the only manifestation of CD. Thus, serological markers of CD should be introduced in the first step of the diagnostic workup of liver diseases in pediatric patients.

Adolescent↗
PubMed2002

Fat composition may be a clue to explain the primary therapeutic effect of enteral nutrition in Crohn's disease: results of a double blind randomised multicentre European trial.

BACKGROUND: Dietary fat has been suggested to determine the therapeutic effect of enteral diets in Crohn's disease. AIM: To assess the efficacy of two whole protein based diets with different fat compositions (n6 polyunsaturated fatty acids v monounsaturated fatty acids) in inducing clinical remission in active Crohn's disease compared with steroids. METHODS: Sixty two patients with active Crohn's disease were randomised to receive, for not more than 4 weeks: (a) a polymeric enteral diet containing 35 g of lipids per 1000 kcal, high in oleate (79%) and low in linoleate (6.5%) (PEN1), (b) an identical enteral diet except for the type of fat which was high in linoleate (45%) and low in oleate (28%) (PEN2), or (c) oral prednisone (1 mg/kg/day). Diets were double blindly administered. The steroid group received a conventional ward diet. Treatment failure was considered when remission was not achieved at week 4. Clinical activity and biological and nutritional parameters were monitored. Independent predictors of remission were identified by stepwise logistic regression analysis. RESULTS: Overall remission rates (by intention to treat) were 20% (4/20) for PEN1, 52% (12/23) for PEN2, and 79% (15/19) for steroids (overall p=0.001; p<0.0005 steroids v PEN1, and p=0.056 PEN2 v PEN1). After excluding those patients who were non-compliant during the first week (per protocol analysis), remission rates were 27%, 63%, and 79%, respectively (p=0.008, steroids and PEN2 v PEN1). After adjusting for confounding variables, PEN1 remained significantly associated with a poor response. CONCLUSION: The type of dietary fat may be of importance for the primary therapeutic effect of enteral nutrition in active Crohn's disease.

Acute Disease↗
PubMed2001

Intestinal handling of an oral oleoyl-estrone gavage by the rat.

Adult Zucker lean (Fa/?) female rats received a single 250 nmol oral gavage of 3H-labelled oleoylestrone in 0.2 ml of sunflower oil. After one hour, samples of arterial, portal and suprahepatic blood, and lymph were obtained and fractioned to determine the amount of radioactivity present in the form of free estrone, acyl-estrone and hydrophilic estrone esters in the blood of each vessel. Lipoprotein fractions (chylomicra + VLDL, LDL, HDL and lipoprotein-depleted plasma) were also analysed as well as the distribution of absorbed 3H-estrone in the intestine, specific organs and carcass. About one third of the oleoyl-estrone dose recovered was found in the tissues, mainly in the blood, the rest remaining relatively untouched in the intestinal content. High hypothalamic estrone uptake (compared with the rest of the brain) was observed. Data from non-radioactive estrone measurements showed a similar pattern of absorption and tissue distribution to that obtained by 3H-estrone tracking alone. In both cases, most of the estrone present in the intestinal lumen was absorbed as intact oleoyl-estrone, but a significant part was absorbed as free estrone. There is a net transfer of 3H-estrone into portal blood HDL, and part of the 3H-estrone is also loaded into lymph-carried chylomicra. A large share of free estrone is filtered by the liver, but most of the acyl-estrone absorbed passes unaltered. The oral administration of oleoyl-estrone results in significant absorption of the unaltered molecule, which is transferred to lymph-carried chylomicra and also directly to plasma HDLs. It may be inferred that the HDL fraction contains the physiological carrier of oleoyl-estrone in its role of ponderostat signal.

Administration, Oral↗
PubMed2001

Bile acid malabsorption in microscopic colitis and in previously unexplained functional chronic diarrhea.

Bile acid malabsorption (BAM) has been described in patients with collagenous colitis. There are no similar studies in lymphocytic colitis. The possibility that BAM might not necessarily be part of the microscopic colitis process and that both entities could simply be concomitant has not been evaluated. Our aim was to assess the frequency and severity of BAM in patients with microscopic colitis as well as in patients with previously unexplained functional chronic diarrhea. Likewise, we wanted to investigate the effect of cholestyramine on the induction and maintenance of remission of these conditions. A [75Se]HCAT abdominal retention test was performed in 26 patients with collagenous colitis, 25 with lymphocytic colitis, and 32 with previously unexplained functional chronic diarrhea. Patients with microscopic colitis who had BAM as well as a subgroup of eight collagenous colitis patients without BAM received treatment with cholestyramine. All patients with previously unexplained chronic diarrhea who had BAM were treated with cholestyramine. Twenty-two (43.1%) patients with microscopic colitis and 24 (75%) patients with previously unexplained functional chronic diarrhea presented with BAM. The frequency of BAM was higher in lymphocytic colitis than in collagenous colitis (60% vs 27%; P = 0.025). Cholestyramine induced clinical remission in 19 of 22 patients with microscopic colitis and BAM, none of eight patients with collagenous colitis without BAM, and all patients with previously unexplained chronic diarrhea and BAM. In conclusion, BAM seems to be common in patients with microscopic colitis-mainly in lymphocytic colitis-and in those with previously unexplained functional chronic diarrhea, suggesting that idiopathic BAM and microscopic colitis are often concomitant conditions. In this setting, cholestyramine seems to be highly effective in stopping diarrhea.

Aged↗
PubMed2001

Corticosteroid-binding globulin synthesis and distribution in rat white adipose tissue.

Corticosterone binding (CB) capacity was determined in visceral and subcutaneous white adipose tissue (WAT), as well as in plasma of lean Zucker rats. Perfusion of rats with saline eliminated most liver and kidney corticosterone binding but did not affect CB in WAT. The cytosol extracts of isolated cells, however, did not bind corticosterone in detectable amounts. By means of a RT-PCR procedure it was found that corticosterone-binding globulin (CBG) was expressed in WAT. By immunohistochemical detection in WAT sections, CBG was seen in a thin layer surrounding the cells near the plasma membrane. These data suggest that the CBG layer surrounding the cells may act as a protective barrier limiting the access of glucocorticoids to adipocytes.

Adipose Tissue↗
PubMed2001

Modulation by leptin, insulin and corticosterone of oleoyl-estrone synthesis in cultured 3T3 L1 cells.

Preadipocytes (3T3 L1) were used between 7 and 14 days after differentiation; they were incubated with 44 nM 3H-esterone. The medium was supplemented with 1 microM recombinant murine leptin, 10 nM recombinant human insulin, or 1 microM corticosterone for up to 72 hr. In a second series of experiments, cells were incubated for 48 hr with different concentrations of leptin, insulin or corticosterone, and compared with controls (plain medium). Cells were harvested, washed in buffer and homogenized, and protein was measured. Lipid extracts of cell homogenates were used for HPLC; the label distribution in free and acylestrone peaks was measured. Overall uptake of estrone (i.e., the sum of free and acylestrone) by cells was not affected by leptin or corticosterone, but strongly reduced by insulin. Leptin and corticosterone increased the synthesis of acyl-esterone in a dose- and time-dependent way. Insulin decreased acyl-estrone synthesis at low concentrations and with little change over time. The results suggest that control of oleoyl-estrone deposition in adipocytes is modulated in at least two distinct steps: (a) estrone uptake, affected by insulin in the physiological range; and (b) synthesis of oleoyl-estrone from cell estrone. The latter may be affected by insulin, but leptin and corticosterone enhance the process.

3T3 Cells↗
PubMed2001

Daily oral oleoyl-estrone gavage induces a dose-dependent loss of fat in Wistar rats.

OBJECTIVE: To establish whether single daily oral doses of oleoyl-estrone result in dose-dependent slimming effects on normal weight rats, and to determine the changes in energy parameters induced by this treatment. RESEARCH METHODS AND PROCEDURES: The effects of a daily oral gavage of oleoyl-estrone (0, 0.2, 0.5, 1, 2, 5, 10, and 20 micromol/kg per day) in 0.2 ml of sunflower oil given over a 10-day period were studied in groups, each of which contained six adult female Wistar rats initially weighing 190 to 230 g. A group of intact control rats receiving no gavage was included for comparison. Body weight and food intake were measured daily. Rats were killed on day 10 of treatment, and body composition (protein nitrogen, lipids, and water), liver lipids, and plasma parameters (glucose, triacylglycerols, total cholesterol, free fatty acids, 3-hydroxybutyrate, urea, aspartate, alanine transaminases, insulin, leptin, and free and acyl-estrone) were measured. RESULTS: The administration of oleoyl-estrone resulted in a dose-dependent loss of body fat, because of a partly maintained energy expenditure combined with decreased food intake. The differences in the energy budget were met by internal fat pools. The changes recorded did not affect the levels of the main plasma energy homeostasis indicators: unaltered glucose, triacylglycerols, free fatty acids, 3hydroxybutyrate, and urea. Protein was accrued even under conditions of severe lipid store drainage. There were no changes in transaminases. No lipid accumulation was recorded in the liver. Plasma insulin and leptin levels decreased with increased oleoyl-estrone doses, whereas the levels of free and esterified estrone increased with treatment, although not in proportion to the dose received. DISCUSSION: Oral treatment with oleoyl-estrone resulted in the specific dose-related loss of fat reserves with little change to other metabolic parameters. These results agree with the postulated role of oleoyl-estrone as a ponderostat signal.

Adipose Tissue↗
PubMed2001

Oral gavage of oleoyl-oestrone has a stronger effect on body weight in male Zucker obese rats than in female.

This study was carried out to determine the effect of sex and oral administration of oleoyl-oestrone on body weight of 12-week-old female and male Zucker obese (fa/fa) rats initially weighing 350-380 g and 405-420 g, respectively. The rats were maintained in standard conditions and given a daily oral gavage of 0.2 ml oleoyl-oestrone dissolved in sunflower oil at a dose of 10 micromol/kg/day for 10 days, and their body weight and food intake was monitored. They were then killed, and their carcass composition (water, lipid, protein and total energy), liver lipids and glycogen and plasma chemistry, insulin, free and total oestrone were measured. Oral administration of oleoyl-oestrone via gavage resulted in significant losses of fat, energy and-ultimately-weight. Treatment with oleoyl-oestrone decreased food intake; the energy expenditure was kept close to that of controls at the expense of internal fat stores. Nevertheless, body protein and plasma metabolite homeostasis were preserved. The slimming effects were more marked in males than in females. Treatment increased circulating acyl-oestrone and reduced to normal levels the high insulin observed in controls. Treatment of genetically obese rats with a daily oral gavage of oleoyl-oestrone resulted in the loss of fat reserves with little modification of other metabolic parameters, except for lower plasma glucose and insulin levels. The results suggest that oleoyl-oestrone, in addition to its slimming effects may be effective as an antidiabetic agent in type 2 diabetes.

Administration, Oral↗
PubMed2000

Hepatopancreatic alterations in Litopenaeus vannamei (Boone, 1939) (Crustacea: Decapoda: Penaeidae) experimentally infected with a Vibrio alginolyticus strain.

As in other countries, the presence of disease has affected and limited the development of shrimp culture in Venezuela. Vibriosis is one of the most prevalent, causing high mortality not only in larval cultures but also in shrimp production. The present work shows the histological changes in hepatopancreas of Litopenaeus vannamei experimentally induced by a strain of Vibrio alginolyticus. The shrimps were infected by the immersion technique, being exposed to a concentration of 5.2 x 10(7) bacteria/ml. As soon as their behavior indicated a moribund condition, the animals were sacrificed, and their hepatopancreata were fixed and processed for histological observation. Light microscopical observations revealed loss of the acinar structure of the digestive gland and sloughing off of cellular lining because of cytolisis. The acinar cellular content was dispersed within the lumina and among the acini. Clusters of hemocytes, in the majority loaded with bacteria, were observed under the connective tissue capsule surrounding the hepatopancreatic lobes and in the hemal spaces of the connective tissue sheath surrounding the tubules.

Animals↗