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H Popper

Publications and source records attributed to H Popper.

At least 289 records · Page 16Linked to original sources
PubMed1965

A new curriculum.

Explore the source record for details and available documents.

Curriculum↗
PubMedDate not supplied

Hepatitis delta virus infection and Labrea hepatitis. Prevalence and role in fulminant hepatitis in the Amazon Basin.

To define more exactly the epidemiology of delta virus infection and confirm its role in causing fulminant Labrea hepatitis in the Amazon Basin, we studied the prevalence of delta virus infection among persons with acute and chronic hepatitis B virus infection in the Boca do Acre district of the southern Amazon Basin. Delta virus infection was found in 24% of asymptomatic hepatitis B virus carriers, 29% of acute nonfulminant hepatitis B cases, 74% of fulminant hepatitis B cases, and 100% of chronic hepatitis B cases. Chronic delta virus infection occurred primarily in older children and adults, while acute and fulminant delta virus infection occurred in young children as well. In fulminant hepatitis cases, delta virus superinfection of hepatitis B virus carriers was the most common serological pattern; histopathologic examination showed features identical to those described in fulminant hepatitis cases of similar etiology in Colombia and Venezuela. Delta virus infection is highly endemic in the southern Amazon Basin and is the principal cause of Labrea hepatitis.

Acute Disease↗
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Protection by antibiotics against experimental focal cholangitis produced in mice by a schistosomicidal isothiocyanate.

Oral administration to mice of high doses of 4-isothiocyano-4'nitrodiphenylamine (amoscanate), a potent antischistosomal drug, produced focal necrotizing lesions of the large intrahepatic and extrahepatic bile ducts and the gallbladder. Coadministration of erythromycin and, to a somewhat lesser degree, of paromomycin, markedly reduced the effects of amoscanate on the biliary tract. These results suggest that amoscanate may be converted to a cholangiotoxic product by one or several constituents of the enteric bacterial flora. Since erythromycin does not affect the antischistosomal activity of amoscanate, coadministration of an antibacterial agent can reduce toxic effects of a drug while full chemotherapeutic activity is maintained. The possibility of toxic effects of metabolites of xenobiotics produced by intestinal bacteria deserves attention and the experimental production of focal intrahepatic and extrahepatic cholangitis by such drug metabolites suggests a possible mechanism in human bile diseases.

1-Naphthylisothiocyanate↗
PubMedDate not supplied

Woodchuck hepatitis and hepatocellular carcinoma: correlation of histologic with virologic observations.

The livers of 33 captive woodchucks were examined histologically in 30 biopsy and 10 autopsy specimens and the findings were correlated with serum determinations for woodchuck hepatitis virus (WHV), surface antigen (WHsAg) and antibody (anti-WHs), and WHV DNA and DNA polymerase. The liver appeared normal in all 3 serum-negative animals, 7 of 16 with indeterminate WHV status, and 1 of 4 with anti-WHs, but not in 10 animals with WHsAg, WHV DNA, and DNA polymerase. Mild hepatic inflammation was found in 7 woodchucks with indeterminate status, 4 with anti-WHs, and 2 with each marker of WHV infection. Significant inflammation was found in 2 of indeterminate status and 4 with every marker, whereas more severe lesions (2 of chronic active type) occurred, almost always in autopsy specimens, in 8 animals with every marker. Eight of 10 animals with all markers had orcein-positive inclusions (Shikata's technique) and 6 had hepatocellular carcinoma associated with acute and chronic hepatic inflammation and, usually, neoplastic nodules in the noncarcinomatous parenchyma. Features distinguishing the woodchuck lesion from human hepatitis B disease were: association of carcinoma with acute hepatic inflammation (but not with cirrhosis) and DNA polymerase in the serum; transition to carcinoma from neoplastic nodules; conspicuous plasma-cellular reaction of hepatic inflammation, and hematopoietic cells in the tumor. Significant hepatic lesions in the woodchucks were regularly associated with serum WHsAg, WHV DNA, and DNA polymerase. In contrast to man, hepatocellular carcinoma in woodchucks was regularly associated with these markers of active viral replication. The nature of the orcein-positive inclusions requires elucidation, although they may assist in screening for similar viruses in other species. The woodchuck may help in the study of the relation between hepatocellular carcinoma and hepatitis B, including the possibility of cocarcinogenic factors.

Animals↗
PubMedDate not supplied

Histologic studies of severe delta agent infection in Venezuelan Indians.

To supplement a detailed epidemiologic study of an outbreak of viral hepatitis in Venezuelan Indians in isolated valleys, apparently resulting from delta agent infection, 10 autopsy specimens were studied histologically and immunocytochemically, and five biopsy specimens were examined. The patients were children and young adults and predominantly males. A sequence of hepatitis from focal necrosis with conspicuous small-droplet steatosis, through massive necrosis, prolonged postnecrotic collapse to early cirrhosis with massive collapse was postulated. The histologic changes tentatively suggest a cytopathic effect of the delta agent without significant indication of lymphocytotoxicity, at least in the parenchyma. Delta agent was demonstrated in hepatocyte nuclei in moderate amounts in the focal-necrotic stage and in isolated cells in the massive-necrotic stage, but in large amounts during the transition to cirrhosis. Whether these patients, in whom neither HBcAg nor HBsAg were demonstrable in the liver, suffered exclusively from superinfection of hepatitis B virus carriers and/or coinfection of hepatitis B virus with the delta agent remains to be resolved. Delta infection may occur in isolated settings with no relation to Italian origin, drug addiction, or polytransfusion. The infection is far more widely spread than previously assumed.

Adolescent↗