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Biomedical subjects

A Mas

Publications and source records attributed to A Mas.

At least 127 records · Page 7Linked to original sources
PubMed1994

Disulfiram-induced hepatitis. Report of four cases and review of the literature.

Liver test abnormalities following disulfiram therapy are common. However, overt disulfiram-induced hepatitis is rare but has a high mortality rate, specially when the etiologic role of disulfiram is not suspected and treatment is not discontinued. We report four cases of disulfiram-induced acute hepatitis with different degrees of severity and review the cases reported in the literature. The clinical spectrum of disulfiram hepatotoxicity ranges from minor elevation of serum aminotransferases to fulminant hepatitis. Although some patients with disulfiram-induced hepatitis have manifestations of hypersensitivity, recent clinical and experimental data suggest that disulfiram hepatotoxicity is produced by the accumulation of toxic metabolites.

Adult↗
PubMed1994

Respiratory toxicity of copper.

Respiratory toxicity of copper was tested in Wistar rats by spraying copper sulfate (330 g/l spray) for daily periods of 1 hr in a self-contained chamber for up to 10 days. The respiratory toxicity was compared with that from intraperitoneal administration of 1 mg Cu/mg body weight and with adequate control rats. Analysis of tissue Cu and Zn was done in lung, liver, kidney, and plasma by using atomic absorption spectrophotometry. Similar organ and subcellular distribution of both elements were found between the two treated groups, and only statistically significant higher levels of Cu were found in plasma and liver. After exposure, Cu and Zn were basically associated with a low-molecular-weight component, which eluted as metallothionein in the postmicrosomal fractions.

Administration, Inhalation↗
PubMed1994

Tissue-specific changes in insulin receptor mRNA concentrations in dexamethasone-treated and adrenalectomized rats.

The relative concentrations of total insulin receptor (IR) mRNA were measured in the epididymal adipose tissue and liver of intact untreated rats, dexamethasone-treated rats, adrenalectomized rats and adrenalectomized rats treated with dexamethasone, using RNA blot assays and a specific IR cDNA probe. Northern blot assays revealed two IR mRNA species of approximately 9.5 and 7.5 kb, in both tissues. Dot-Blot assays followed by densitometry indicated that dexamethasone induced an approximately three-fold increase in IR mRNA in liver, but not in epididymal adipose tissue. By contrast, neither adrenalectomy alone nor the combination of adrenalectomy plus dexamethasone treatment altered the IR mRNA concentrations in liver nor in adipose tissue, which indicates that adrenalectomy was able to prevent the stimulation of IR gene expression caused by dexamethasone in rat liver. These results provide evidence for an "in vivo" tissue-specific regulation of IR gene expression, at the mRNA level, in rats under experimental conditions of an excess or insufficiency of glucocorticoids.

Adipose Tissue↗
PubMed1994

Endoscopic sclerotherapy in upper gastrointestinal bleeding due to the Mallory-Weiss syndrome.

OBJECTIVES: Therapeutic endoscopic techniques have changed the need for emergency surgery in gastrointestinal bleeding episodes. However, there is only little information about endoscopic therapies in severe gastrointestinal bleeding due to the Mallory-Weiss syndrome. The aim of this clinical study was to assess the usefulness of early endoscopic examination and sclerotherapy for severe or recurrent bleeding due to the Mallory-Weiss syndrome. METHODS: We studied all 50 cases of gastrointestinal bleeding secondary to the Mallory-Weiss syndrome seen in 2175 consecutive emergency endoscopic examinations performed in a University Hospital over a 3-year period. Endoscopic sclerotherapy (1/10000 adrenaline + 1% polidocanol) was performed in all patients with active bleeding or visible vessel at endoscopic examination. The remaining patients were medically treated. RESULTS: Active bleeding or a visible vessel were found in 13 patients; definitive hemostasis was obtained in all cases with sclerotherapy. The remaining 37 patients were successfully treated by conservative therapy. On admission, the severity of the hemorrhagic episodes was significantly higher in patients treated with sclerotherapy than in those who did not require this procedure. An esophageal perforation, successfully managed by conservative means, was the only complication recorded in the subset of patients undergoing sclerotherapy. CONCLUSIONS: Severe bleeding due to Mallory-Weiss syndrome can be successfully treated by sclerotherapy. Early endoscopic examination is an accurate procedure in identifying patients who do not require sclerotherapy.

Adult↗
PubMed1993

[Diagnosis of ornithine carbamoyl transferase deficiency and heterozygote detection with allopurinol loading test].

BACKGROUND: Allopurinol loading test is based on the inhibition of pyrimidine biosynthesis and the subsequent increase in orotic acid excretion caused by a single dose of allopurinol. Abnormally elevated amounts of orotic acid excretion are demonstrated in ornithine carbamoyl transferase (OCT) deficiency patients and heterozygotes as well as in other disorders of urea cycle. Biochemical studies performed for the diagnosis of one patient and carrier detection in her family are presented. METHODS: Amino acids: ion exchange chromatography; ammonium: method of Van Anken and Shiphorst; orotic acid: modification of Adachi et al, and allopurinol test following Brusilow et al. RESULTS: The characteristic amino acid profile of the patient together with her clinical history suggested the diagnosis of OCT deficiency, which was confirmed with protein and allopurinol loading test. The heterozygote condition became evident only by means of allopurinol test in 2/5 female relatives. CONCLUSIONS: Allopurinol test is a useful tool for the preliminary investigation of urea cycle function, avoiding the possible hyperammonemia caused by other test, and permitting extensive familial studies without hospitalization. It results more informative than the protein loading test.

Allopurinol↗
PubMed1993

Liver transplantation for acute liver failure: analysis of applicability.

BACKGROUND: Liver transplantation has emerged as the most important advance in the therapy of acute liver failure. To assess the applicability of liver transplantation in this setting, the outcome of 62 patients with acute liver failure consecutively admitted to hospital was analyzed. METHODS: Criteria for indicating liver transplantation were grade III-IV hepatic encephalopathy or progression of encephalopathy following a transient improvement. In subfulminant cases, liver transplantation was also indicated when no improvement was observed after a 3-day period of conservative treatment. RESULTS: Thirteen (21%) of the 62 patients never met criteria for transplant indication; all of them were discharged after receiving conventional therapy. Twenty-one (34%) patients with criteria for indicating liver transplantation could not receive the transplant because of either contraindications (17 patients; only 1 being discharged from hospital) or death before donor organ availability (4 patients). Finally, 28 (45%) patients received a liver transplant and 22 were discharged from hospital. CONCLUSIONS: The applicability of liver transplantation in acute liver failure is relatively low. Considering the high survival rate (79%) obtained in the patients with transplantations and the poor survival rate (6%) observed in those who could not be transplanted, efforts should be made to increase liver transplant applicability to improve the prognosis in acute liver failure.

Adolescent↗
PubMed1993

Changes in plasma copper and zinc during rat development.

The association of copper and zinc to plasma ligands was studied during the rat perinatal period. Analysis was carried out by means of column chromatography (Sephadex G-150) and atomic absorption spectrophotometry. Levels of copper were low at birth and showed a sharp increase after day 10. This increase was similar to that of ceruloplasmin activity as well as its association with copper. Zinc levels, instead, showed higher levels before birth and decreased slowly toward the adult values. Association of zinc to albumin and associated proteins showed a pattern similar to the decrease in plasma zinc levels.

Aging↗
PubMed1992

Uptake of 67Cu by isolated human trophoblast cells.

The isolated human trophoblast was used as a system to analyze the effects of different physiological ligands on cellular uptake of copper. The results show that the uptake of copper by these cells follows a similar pattern for the ligands tested (histidine, albumin and ceruloplasmin) as that for copper chloride. The process follows a typical hyperbolic curve at 37 degrees C. The initial phase of uptake follows a linear pattern during 30 min at 37 degrees C and at least 60 min at 4 degrees C from which the uptake rate is calculated. However, a significant decrease in the uptake rate is observed for albumin. The effect of histidine on stimulating copper transport is observed in the presence of serum, a phenomenon which is considered to be due to the release of copper that is bound to albumin. These results support the role of ceruloplasmin as a copper transport protein which releases copper at the cell surface, and a subsequent transport of the released copper in a manner similar to that of copper chloride or copper-histidine complexes.

Biological Transport↗
PubMed1992

Selective intestinal decontamination in the prevention of bacterial infection in patients with acute liver failure.

To investigate whether selective intestinal decontamination from oral administration of poorly absorbable antibiotics is effective in preventing bacterial infection in patients with acute liver failure, the incidence of nosocomial infection in 34 patients consecutively admitted to hospital between 1985-1990 and treated with either neomycin + colistin + nystatin or norfloxacin + nystatin (group I) was compared to the incidence of infection in 57 patients who did not receive oral, poorly absorbable antibiotics and who were consecutively admitted between 1972-1984 (group II). Patients from groups I and II had similar clinical and laboratory data at hospital admission. Twelve patients from group I and 33 from group II developed bacterial infection during the study period. The probability of infection was significantly different (p = 0.0083) in the two groups: 19% vs. 39% at the 3rd day of admission, 33% vs. 74% at the 7th day, and 48% vs. 78% at the 14th day, respectively. This difference was due to a different rate of infection from enterobacteria. Enterobacteria caused one infectious episode in group I and 24 in group II (p less than 0.001). The incidence of infections caused by other organisms, however, was similar in both groups (15 and 19 episodes, respectively). These results suggest that selective intestinal decontamination is useful in reducing the risk of infection from enterobacteria in patients with acute liver failure.

Adult↗
PubMed1992

Portal hypertension in acute liver failure.

Twenty five patients with acute liver failure were measured for hepatic venous pressure gradient as an index of portal pressure during the course of a transjugular liver biopsy. Hepatic venous pressure gradient ranged from 4 to 24.5 mm Hg with a mean of 12.8 (5.3) mm Hg (normal values less than 5 mm Hg). All patients but one had increased portal pressure gradient. Portal hypertension correlated with the degree of architectural distortion of the liver, as suggested by a direct correlation between hepatic venous pressure gradient and the area of reticulin collapse, evaluated by means of a morphometric analysis on Sirius red stained liver slides (r = 0.43, p less than 0.05). Hepatic venous pressure gradient was significantly higher in patients with ascites (15.1 (5) mm Hg, n = 15) or renal failure (14.4 (5.3) mm Hg, n = 16) than in those without (9.3 (3.4) mm Hg and 10.1 (4) mm Hg, respectively; p less than 0.05). Portal hypertension was associated with systemic vasodilation and a hyperkinetic circulatory state, with decreased arterial pressure, and peripheral resistance and increased cardiac output.

Acute Kidney Injury↗