Search PubMed⌕ Search

Biomedical subjects

G Gasbarrini

Publications and source records attributed to G Gasbarrini.

At least 505 records · Page 28Linked to original sources

Oxmetidine (SK&F 92994): pharmacokinetic study in patients with in patients with liver cirrhosis.

The pharmacokinetics of oxmetidine (SK&F 92994) were investigated in nine cirrhotic patients and compared with ten control subjects with gastroduodenal ulcers, but without any symptoms of hepatic pathology. On two separate occasions each patient received 200 mg oxmetidine as a single oral dose and 100 mg as a single intravenous dose. In the cirrhotics, the bioavailability of the oral dose and the plasma elimination half-life after both oral and intravenous administration were significantly higher than in the controls. Moreover, a positive correlation was found between the plasma elimination half-lives and the biochemical parameters of cholestasis. Such findings indicate that in severe liver disease and in cholestasis the accumulation of oxmetidine in the circulation may limit the use of this drug.

Aged↗

Comparative pharmacodynamics of furosemide and muzolimine in cirrhosis. Study on renal sodium and potassium handling and renin-aldosterone axis.

Ten male cirrhotic patients with ascites and reduced renal function were randomly given equivalent doses of furosemide and muzolimine by the oral route, through a single blind cross-over protocol. Renal function, electrolyte plasma concentrations and urinary excretions and renin-angiotensin-aldosterone system components were evaluated under basal conditions and after drug administration. The diuretic and saluretic effects being equal, the response to muzolimine was initially weaker but more prolonged than to furosemide, without rebound phenomena. The furosemide-induced natriuresis was in part related to the filtered sodium load, whereas muzolimine natriuresis was only correlated to the inhibition of tubular sodium reabsorption. No potassium wasting effect was seen after muzolimine administration. Transient plasma potassium concentration reduction observed during muzolimine suggests an ion shift within the intracellular compartment. Therefore, a possible interaction of the drug with cellular sodium active transport systems can be hypothesized. A significant increase of plasma renin activity was observed after furosemide. No significant changes were seen after muzolimine administration.

Angiotensin II↗

Specificity of leucocyte migration inhibition test in coeliac disease. A reassessment using different gluten subfractions.

Production of leucocyte migration inhibition factor by peripheral blood leucocytes in response to challenge with gluten fractions has been proposed as a reliable in vitro test for the diagnosis of coeliac disease. We have performed the leucocyte migration inhibition test with two different gluten fractions, GFIII and B2, in untreated and treated coeliac patients, patients with other intestinal diseases (abnormal controls) and healthy controls, and evaluated the sensitivity, specificity and positive and negative predictability of the test for the diagnosis of coeliac disease. Using GFIII as antigen leucocyte migration was significantly inhibited, compared to healthy controls, not only in treated and untreated coeliacs but also in abnormal controls. Using B2 gluten subfraction as antigen only treated coeliacs and abnormal controls differed significantly from healthy controls. The elevated number of abnormal controls showing migration inhibition consistently affected the diagnostic value of the test, which did not vary using B2 subfraction instead of GFIII as antigen. Our study confirms previous observations of gluten sensitization, as detected by leucocyte migration inhibition, in coeliac patients but strongly questions the claim that coeliac disease can be diagnosed on the basis of a positive leucocyte migration inhibition test without the need for intestinal biopsy.

Adolescent↗

Clinical applications of scanning electron microscopy in gastrointestinal diseases.

We considered the role of scanning electron microscopy (SEM) in clinical investigation of different gastrointestinal diseases. The following clinical applications of SEM may be suggested on the basis of our original data and those reported in literature: in peptic ulcer: assessment of the completeness of healing, by observing the mucosal surface architecture of the scars; identification of mucosal changes, namely enterocytic surface membrane alterations, predictive of recurrence; in coeliac disease: early assessment of the response to gluten-free diet and follow-up of the patients by staging the process of mucosal repair in cerebriform, intermediate and villous patterns; in ulcerative and Crohn's colitis: enhancement of the diagnostic sensitivity of perendoscopic biopsy, by detecting differences in surface structure of mucosa surrounding ulcers in both diseases. This is subverted in ulcerative colitis and preserved in Crohn's colitis. Finally the complementary role of SEM in relation to endoscopy and light microscopy is emphasized.

Adolescent↗

Return of splenic function after splenectomy: how much tissue is needed?

Ninety patients whose spleen had been removed either because of trauma (41 cases) or as an elective procedure (49) were investigated for return of splenic function by counting pitted red cells and examining spleen scans made after injection of heat damaged 99mTc labelled red cells. There was no significant difference in the proportion of pitted red cells between the two groups of patients. Evidence of splenic tissue in scintiscans was not invariably associated with low pitted red cell values, suggesting that the presence of splenic tissue did not necessarily mean return of splenic function. In every patient whose proportion of pitted red cells was less than 16.2% the scintiscan showed splenic uptake. The proportion of patients with pitted red cell values below 16.2% was significantly higher in the group operated on for trauma, and it is concluded that this was due to splenosis. A high inverse correlation between pitted red cell counts and computed splenic volumes was found. Patients with pitted red cell values of less than 16.2% had computed volumes of 22-133 cm3; below this range the proportion of pitted red cells rose very sharply. These results confirm that splenosis occurs in adults, though less often than in children, and suggest that when splenic tissue is to be implanted a graft of at least 20-30 cm3 is needed to ensure satisfactory return of splenic function.

Adolescent↗

Circulating hepatocyte membrane-specific autoantibodies in chronic active hepatitis type B. Relation to virus replication activity and liver cell necrosis.

Sera from two groups of untreated HBsAG-positive patients with chronic active hepatitis on liver biopsy were tested for antibodies to liver cell membrane antigens (liver-specific protein, LSP; and liver membrane antigen, LM-Ag). Among the 14 HBeAg-positive cases, seven (50%) were positive for anti-LSP, whereas only two (13%) of 15 anti-HBe-positive cases circulated this antibody. Liver membrane autoantibody (LMA) was detected only in two sera from delta-positive patients (1 HBeAg positive and 1 anti-HBe positive). Anti-LSP-positive patients presented transaminase values significantly higher than those of the negative cases. Our data do not support the hypothesis that a liver-specific autoimmune mechanism plays a significant role in the immunopathogenesis of liver cell necrosis in anti-HBe-positive chronic active hepatitis type B. The relationship between hepatocyte necrosis and anti-LSP antibody response is confirmed.

Adult↗

Analysis with OKT monoclonal antibodies of T-lymphocyte subsets present in blood and liver of patients with chronic active hepatitis.

The relative distribution of T lymphocyte subsets, as defined by the monoclonal antibodies OKT, was determined by cytofluorimetric analysis in peripheral blood and in cells isolated from liver biopsies of 31 patients with chronic active hepatitis (CAH). The percentage of peripheral blood lymphocytes binding OKT8 (directed against cytotoxic/suppressor T cells) was found to be elevated in patients with HBsAg and HBeAg positive chronic active hepatitis. Patients with CAH who had seroconverted to anti-HBe, had an increased number of OKT3-positive cells in their blood, which was directed against a common T cell surface antigen, associated with a decreased number of OKT8 positive cells. Lymphocytes isolated from liver biopsies of patients with CAH presented a general increase of OKT8-positive cells associated with a decreased number of OKT4-positive (helper/inducer) T cells. It is likely that OKT8-positive cells found in liver biopsies represent cytotoxic T cells directed against either viral or liver cell determinants.

Adult↗

Jejunal intraepithelial lymphocytes in coeliac disease: are they increased or decreased?

We have quantified intraepithelial lymphocytes in the same biopsy series (21 healthy controls, 14 untreated coeliacs, 15 treated coeliacs, five non-coeliac patients with an abnormal jejunal mucosa) both as counts/100 epithelial cells and using as reference value a fixed area of muscularis mucosae. As expected, the number of intraepithelial lymphocytes/100 epithelial cells was significantly higher in untreated and treated coeliacs than in healthy controls, as well as in untreated when compared with treated coeliac patients. Otherwise, the number of intraepithelial lymphocytes lying in the area of mucosal surface overlying a fixed area of muscularis mucosae was significantly lower in treated and untreated coeliacs, than in healthy controls, as well as in untreated when compared with treated coeliacs. A highly significant inverse correlation was found between the number of intraepithelial lymphocytes/100 epithelial cells and the mucosal surface area measured as surface to volume ratio. When the number of intraepithelial lymphocytes/100 epithelial cells was corrected for differences in surface to volume ratio, the results were very similar to those obtained by a muscularis mucosae related count. In five coeliacs both intraepithelial lymphocyte and enterocyte muscularis mucosae related counts rose after a period of gluten free diet but the mean per cent increase of enterocytes was significantly higher than that of lymphocytes. Our results are compatible with a decrease in the total number of intraepithelial lymphocytes in the entire small bowel in coeliac disease. In untreated coeliac mucosae, however, a derangement in the usual proportions of intraepithelial lymphocytes and enterocytes is evident and may be important in the pathogenesis of coeliac disease.

Adult↗

Ultrastructural aspects of duodenal mucosa repair during treatment of peptic disease.

We applied scanning electron microscopy (SEM) to the study of duodenal ulcer healing during treatment with an H2-receptor antagonist (ranitidine). We also evaluated the changes in the duodenal mucosa close to the lesion, which appeared endoscopically and histologically normal. Endoscopic biopsies were taken from 8 patients both on the edge of the ulcer and in the upper duodenum, before and after 1, 2, 3, 4 and 8 weeks of treatment. Endoscopy revealed a decrease of the ulcer crater after the first week and a complete healing after three weeks of therapy. The ulcer edge presented a subtotal mucosal atrophy, cellular exfoliation (dome-shaped cells) and changes in microvilli (bridging, branching, blebs). In the first week of treatment, reepithelization was observed: however, cellular exfoliation and changes in microvilli persisted at least up to the end of the first month of treatment. Short and stumped villi began to reappear after one month. The mucosa farthest from the lesion showed the same alterations but to a lesser extent. The changes tended to decrease after treatment. Two months after the end of treatment the duodenal mucosa was endoscopically and histologically normal, while SEM showed altered microvilli. SEM allowed us to investigate the morphogenesis of mucosal repair and to identify minimal cellular alterations which could represent the morphological basis of the disease and its possible recurrence.

Adult↗

Study on coagulation profile of patients with cirrhosis of the liver undergoing elective fibreoptic injection sclerotherapy of oesophageal varices.

In order to establish whether injection sclerotherapy of oesophageal varices could bring about a worsening of the coagulation abnormalities of patients with cirrhosis, the platelet count and the coagulation profile were monitored prior to, then 30 min and 18 h after, the injection in 8 patients undergoing 18 sclerotherapy sessions. Under basal conditions the platelet count, prothrombin activity, normotest and antithrombin III were all reduced; fibrinogen was in the low, and partial thromboplastin time in the high, normal range. A significant shortening of PTT and a further reduction in the platelet count, in the normotest and in fibrinogen occurred after 30 min. On one occasion laboratory evidence of disseminated intravascular coagulation was observed. After 18 h most parameters approached basal values, but the normotest remained persistently reduced. Even though a transient activation of the coagulation process, with consumption of platelets and the liver-dependent clotting factors took place after sclerotherapy in most cases, leading in one to self-limiting disseminated intravascular coagulation, haemorrhagic complications did not occur in our patients. These results suggest that injection sclerotherapy did not lead to clinically significant deterioration of coagulation even in patients with abnormal coagulative function. The observed changes appeared to be self-limiting and confined to the laboratory level in all cases.

Adult↗

Ultrasonographic study of portal venous system in portal hypertension and after portosystemic shunt operations.

One hundred sixty patients with portal hypertension were examined by means of ultrasonography in order to evaluate the sensitivity of this technique in the diagnosis of intrahepatic portal hypertension and in the detection of portal vein thrombosis. Thirty-eight of these patients were selected for a portosystemic shunt and were reexamined after operation to assess the value of ultrasonography as a screening test for the patency of surgical portosystemic shunts. In patients with intrahepatic portal hypertension the main ultrasonographic findings observed were dilatation of the portal trunk of more than 1.3 cm (56.6% of cases), patency and dilatation of the umbilical vein (5.8%), presence of intra-abdominal collateral vessels (11.6%), splenomegaly with dilatation of splenic vein radicles at the hilus (91.3%), and disappearance of normal caliber variations during respiration in splenic or mesenteric veins (78.5% and 88.4%, respectively). The disappearance of normal caliber variations proved a highly specific and sensitive finding. Partial or total occlusion of the portal trunk was observed at ultrasonography in 19 of 21 (90.5%) patients with portal vein thrombosis. Surgical portosystemic shunts were displayed in 28 of 37 patients (75.7%). Ultrasonography seems to be the most important noninvasive tool in the diagnosis of portal hypertension. In patients selected for surgical portosystemic shunts ultrasonography supplies morphologic data regarding liver parenchyma and abdominal vascular anatomy, and it should be performed as a routine screening test for assessment of surgical shunt patency.

Humans↗

T-lymphocyte subsets in adult coeliac disease.

1. As a defect of suppressor function has been hypothesized in the pathogenesis of coeliac disease, we measured, by monoclonal antibodies, the inducer/suppressor T-cell ratio in adult coeliac disease. 2. No statistical difference was observed between coeliac patients and healthy controls, irrespective of treatment and HLA status. 3. These results do not show an imbalance in the inducer/suppressor T-cell ratio in coeliac disease.

Adult↗

Hepatitis B virus markers in hematologic patients: relation to transfusion treatment and hospitalization.

Screening tests for hepatitis B virus (HBV) markers were performed in 266 hematologic patients in order to evaluate the role of transfusion therapy in HBV infection and to identify other possible causes of the high rate of HBV markers positivity in oncohematologic units. As control groups we tested 99 nonhematologic polytransfused patients, 66 nonhematologic, nontransfused inpatients with various diseases and 72 subjects randomly selected from the general population. Higher HBV markers prevalence was found in hematologic patients, nonhematologic polytransfused patients and nonhematologic, nontransfused inpatients than in the general population. HBV markers prevalence correlated with the length of hospitalization in all inpatients studied. Our data suggest that hospital admission is a major factor in HBV transmission in hematologic patients and in other inpatients studied. Blood transfusions represent a risk factor only when utilized as chronic treatment.

Adolescent↗