Harold Dunsford

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Different lineages of hepatocellular carcinoma (HCC) were identified by the application of selected monoclonal antibodies to the study of the sequential histopathological changes which occurred during two regimens of chemical carcinogenesis in the rat. One regimen, that of Solt-Farber, caused prominent oval cell proliferation and large multiple neoplastic(More)
The tumorigenic activity of manufactured gas plant residue (MGP) was evaluated in female A/J mice using a F0927 basal gel diet system. Adulterated diets containing MGP (0.10% or 0.25%) or benzo[a]pyrene (B[alpha]P; 16 or 98 ppm) were fed for 260 days. A negative control group was maintained on a nonadulterated basal gel diet. Mice dosed with a single ip(More)
A review of the morphologic, autoradiographic, and phenotypic analysis of the cellular changes seen during induction of cancer of the liver in rats by chemical carcinogens is used to develop an alternative to the established hypothesis that chemically induced hepatocellular carcinoma arises from premalignant nodules. The authors propose that hepatocellular(More)
Transgenic mice that overproduce the hepatitis B virus large envelope polypeptide and accumulate toxic quantities of hepatitis B surface antigen (HBsAg) within the hepatocyte develop severe, prolonged hepatocellular injury that initiates a programmed response within the liver, characterized by inflammation, regenerative hyperplasia, transcriptional(More)
Although proliferation of small ductular-like cells, designated oval cells, is often observed during the early stages of chemically induced hepatocarcinogenesis, their role during the carcinogenic process remains controversial. To investigate the possibility that oval cells may give rise to preneoplastic lesions that ultimately progress to hepatocellular(More)
The early cellular and molecular changes in the Solt-Farber model of hepatocarcinogenesis with and without initiation was studied by using histochemical, immunohistochemical, and in situ hybridization techniques. Increased cellularity was observed in the periductal space in both models 32 to 56 h after partial hepatectomy. These periductal cells and Ito(More)
We have recently reported that cell lines of nonparenchymal origin isolated from rat liver and pancreas, which have been suggested to be the progeny of a facultative stem cell compartment in vivo, express an unusual combination of keratins (K). These cell lines express K8 and K14 but not K18 and K5, their normal partners in filament formation (Bisgaard HC,(More)
Monoclonal antibodies (moabs) to neoplastic and preneoplastic liver cells in rats have been selected to follow cellular changes in the livers during chemical carcinogenesis. The moabs were induced by immunizations of BALB/c mice with four partially purified liver cell preparations: 1) oval cells induced in male Fischer rats fed 0.05% N-2-acetylaminofluorene(More)
Fifty-nine transgenic mice from a lineage that overproduces the hepatitis B virus large envelope polypeptide and accumulates high intrahepatic concentrations of hepatitis B surface antigen were followed for evidence of liver disease throughout their 24-month life span. By 4 months of age all mice displayed biochemical and histological evidence of moderately(More)
The present study determined tumorigenicity, tumor classification and DNA damage induced in infant mice by benzo[a]pyrene (B[a]P) or Manufactured Gas Plant (MGP) residues after a single exposure. Male and female B6C3F1 mice were exposed to B[a]P or MGP residue from a single environmental site (MGP-4) and males were also exposed to MGP residue composite from(More)