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Biomedical subjects

F Schaffner

Publications and source records attributed to F Schaffner.

At least 181 records · Page 10Linked to original sources
PubMed1965

Changes in hepatic structure in rats produced by breathing pure oxygen.

The livers of rats exposed to pure oxygen were examined electron microscopically to study toxic effects of oxygen in a metabolically sensitive organ. Pressures of 1/3 (258 mm Hg), 1 (760 mm Hg), and 3 (2280 mm Hg) atmospheres were used, with exposures up to 90 days with the lowest pressures. The first changes in the hepatocytes were loss of glycogen and enlargement of mitochondria with development of mitochondria with bizarre shapes which were seen after 3 days at 258 mm, 1 day at 760 mm, and 3 hours at 2280 mm. These changes were followed by formation of increased numbers of cristae, membranes surrounding mitochondria, autophagic vacuoles, and polyribosome clusters. After 2 weeks at 258 mm, which is the pressure of the atmosphere of space cabins, numerous mitochondrial myelin figures appeared but the mitochondrial enlargement had begun to regress. After 90 days at 258 mm, the liver cells appeared almost normal except that many pigment granules had accumulated in the pericanalicular zones. The changes were non-specific and seemed to parallel biochemical alterations recorded elsewhere. They are not considered the result of toxicity but rather of adaptation. These atmospheres, which are used in clinical medicine and in space travel, appear to have no permanent deleterious effects on the liver in rats under the conditions of this experiment.

Adaptation, Physiological↗
PubMedDate not supplied

Randomized controlled trial of quinacrine for the treatment of HBsAg-positive chronic hepatitis.

Several drugs which react with DNA decrease hepatitis B viral (HBV) DNA polymerase activity in vitro. Because such an alteration of viral replication, if produced in patients with hepatitis B surface antigen (HBsAg)-positive chronic hepatitis, may lead to elimination of viral infection, we conducted a controlled trial of the use of the intercalating agent, quinacrine hydrochloride, in treatment of HBsAg-positive chronic hepatitis. No patient converted from HBsAg positive to negative during the trial and no consistent effect on HBV DNA polymerase activity was noted. Following treatment, elevated transaminase values and alterations of HBV markers were observed in several patients. Fluctuations of transaminase values and HBV markers may reflect alterations in host immunity and viral replication. Quinacrine alone is ineffective in therapy of chronic HBV infection. Additional study with intercalating agents, perhaps in conjunction with other drugs, is suggested.

Adult↗
PubMedDate not supplied

The liver in the acquired immunodeficiency syndrome: a clinical and histologic study.

We reviewed the clinical data and hepatic histologic findings of 25 patients with the acquired immunodeficiency syndrome who underwent 29 liver biopsies. Our experience indicates that the only hepatic feature characteristic of acquired immunodeficiency syndrome is serologic evidence of exposure to the hepatitis B virus. The most common histologic finding was macrovesicular steatosis. Granulomas appeared in seven patients and were due to mycobacterial disease (3 patients), histoplasmosis (1 patient), adverse reaction to sulfonamide (2 patients) and unknown causes (1 patient). The clinical indication for liver biopsy was not significantly different in the patients without or with granulomas or with granulomas secondary to mycobacteria or fungi. Mycobacteria were cultured from all histologically positive specimens and one histologically negative specimen. Liver biopsy should be performed in any patient with acquired immunodeficiency syndrome who has unexplained fever, hepatomegaly or abnormal results of serum biochemical liver tests, and all specimens should be stained and cultured for mycobacteria and fungi.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

The intrahepatic biliary epithelium in the guinea pig: is hepatic artery blood flow essential in maintaining its function and structure?

To determine whether hepatic artery blood flow is essential in maintaining the function and structure of bile ductules/ducts, the acute effects of hepatic artery ligation on bile secretion and hepatic ultrastructure were examined in anesthetized, bile duct-cannulated guinea pigs. Sixty minutes after hepatic artery ligation, spontaneous bile flow (5.08 +/- 0.4 microliter per min per gm liver) was virtually the same as that before hepatic artery ligation (5.31 +/- 0.3 microliter per min per gm), as were the choleretic effects of 10 CU per kg per 30 min secretin (7.14 +/- 0.9 vs. 7.21 +/- 0.9 microliter per min per gm), 300 micrograms per kg per 30 min glucagon (6.72 +/- 0.9 vs. 6.59 +/- 0.8 microliter per min per gm) and 60 mumoles per kg per 30 min glycochenodeoxycholate (6.43 +/- 0.6 vs. 6.45 +/- 0.6 microliter per min per gm). The failure of hepatic artery ligation to affect bile secretory function could not be attributed to the existence of collateral arterial blood flow to the liver. First of all, hepatic artery ligation resulted in diminishing significantly hepatic venous, but not portal, oxygen content. More importantly, in isolated guinea pig livers, perfused through the portal vein alone, secretin, glucagon and glycochenodeoxycholate produced changes in bile flow and composition similar to those seen in vivo. Electron microscopy showed no major ultrastructural changes of hepatic parenchyma and biliary epithelium 2 hr after hepatic artery ligation, or 2 hr after perfusing the liver through the portal vein alone save for some portal edema in the latter instance.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

A prospective clinical trial of D-penicillamine in the treatment of primary biliary cirrhosis.

We conducted a prospective clinical trial to assess the relative efficacy and safety of high- vs. low-dose D-penicillamine in patients with primary biliary cirrhosis. Following clinical tests and liver biopsy diagnostic of primary biliary cirrhosis, 56 patients were randomized to receive either 250 or 750 mg D-penicillamine daily. Patients were monitored with clinical tests and annual liver biopsy. Randomization produced two groups without differences in demographic, clinical or histologic characteristics. During the trial, no differences were seen between the mean change in liver test results in patients in either treatment group. The 11% per year rise of bilirubin in the 750 mg dose group during the first 3 years was not significantly different from the 18% per year rise in the 250 mg dose group. No patient showed improvement on liver biopsy although patients on 750 mg D-penicillamine deteriorated more slowly. Side effects, particularly rash and dysgeusia, were more common in the 750 mg dose group. The frequency and severity of side effects were responsible for the early conclusion of our trial. Twenty-six patients experienced side effects necessitating discontinuation of D-penicillamine. No evidence of increased efficacy was demonstrated by high-dose D-penicillamine therapy, and side effects were observed in patients on 250 mg D-penicillamine daily. With the severity of adverse effects and continued progression of disease, D-penicillamine is not a clinically useful therapy in primary biliary cirrhosis.

Bilirubin↗
PubMedDate not supplied

The role of alcoholism and liver disease in the appearance of serum antibodies against acetaldehyde adducts.

We recently presented preliminary data indicating the presence of antibodies against acetaldehyde adducts in sera of over 70% of alcoholic patients. To assess the respective roles of liver disease and alcohol consumption as well as the specificity of this immune response, 141 patients in various stages of alcoholic and nonalcoholic liver diseases were tested by a hemagglutination assay. Sixty-three (73%) of 86 alcoholics had antibody titers above control levels (p less than 0.0001). Alcohol consumption of these individuals was significantly higher (p less than 0.001) than that of those alcoholics with normal titers. Twenty-two patients (39%) with nonalcoholic liver diseases also had elevated levels of antibodies against acetaldehyde adducts (p less than 0.0005); of these, 8 had primary biliary cirrhosis (7 in Stages III and IV), 9 had chronic active hepatitis (6 with cirrhosis) and 5 had acute (virus- or drug-induced) hepatitis. Antibody titers did not correlate with levels of transaminase or alkaline phosphatase activity, nor with bilirubin, and albumin. However, in 52 alcoholics and in nonalcoholic patients with biopsy-confirmed liver disease, the highest titers were seen in the more advanced stages of liver damage. Thus, in addition to alcohol consumption, severity of liver disease may play a role in the appearance of circulating antibodies against acetaldehyde adducts.

Acetaldehyde↗