Mutational activation of beta-catenin and cyclin D1 over-expression are a frequent change in mouse hepatic tumors. Although activated beta-catenin may bind to T cell factor (TCF) family members and transcriptionally activate the cyclin D1 gene, either beta-catenin or cyclin D1 may be activated by various pathways independently of beta-catenin mutations. In this study, we investigated beta-catenin activation and mutations, cyclin D1 expression, H-ras mutations and phosphorylation of extracellular signal regulated protein kinases 1/2 (ERK1/2), Akt and glycogen synthetase kinase 3beta (GSK3 beta) in mouse hepatic carcinogenesis. Nuclear/cytoplasmic staining of beta-catenin, a sign of beta-catenin activation, was frequently observed in association with the high nuclear cyclin D1 labeling index in the hepatic tumors at the late stage of carcinogenesis. The beta-catenin activation was further suggested by the fact that all hepatocellular carcinoma (HCC) cell lines examined showed the nuclear beta-catenin/TCF4 complex together with cyclin D1 over-expression. However, the fact that only 31.8% (7/22) of the lesions with the nuclear/cytoplasmic beta-catenin staining showed beta-catenin mutations indicated that beta-catenin was activated not only by its own mutations but also by other reason(s). On the other hand, there was no correlation between the beta-catenin/cyclin D1 activation and the H-ras mutations or phosphorylation of Akt, GSK3 beta and ERK1/2, although GSK3 beta was frequently over-expressed in the tumors. These results indicate that, although beta-catenin and cyclin D1 activation are well correlated, the Akt/GSK3 beta and ras/ERK1/2 pathways may not play a major role in the beta-catenin/cyclin D1 activation.
Chromosomal alterations were investigated in hepatocellular carcinoma cell lines, primary tumors and liver epithelial cell lines derived from normal livers of C57BL/6JxC3H/HeJ F(1) and C3H/HeJxC57BL/6J F(1) mice. In the primary tumors, non-random gain of chromosomes 15 and 19 was found in seven and five of 14 hepatocellular carcinomas, respectively. On the other hand, in the cases of both liver epithelial and hepatocellular carcinoma cell lines, frequent changes were loss of chromosomes 4 (4/9 cell lines) and 12 (3/9) as well as gain of chromosomes 15 (5/9) and 19 (4/9). These results indicate that the chromosomal gain is associated with both in vivo carcinogenesis and establishment of cell lines, while the loss is specific for the latter. PCR analysis using polymorphic microsatellite DNA markers revealed that the loss of chromosome 12 as well as chromosome 4 was much more frequent for the C57BL/6J hepatocarcinogenesis-resistant rather than the susceptible C3H/HeJ strain.
The microwave spectra of CH380SeCN, CH378SeCN, CH380Se13CN, CH380SeC15N, sym-CH2D80SeCN, and asym-CH2D80SeCN have been observed. In order to determine the rotational constants of 13CH380SeCN, we used the transition frequencies observed by Landsberg. From these spectra the complete rs coordinates of seven atoms have been calculated using Kraitchman’s equation. The structural parameters (bond lengths in Å(1Å=0.1 nm) and angles in degree) are: r(C1–H1)=1.073(4), r(C1–H2)=1.083(6), r(C1–Se)=1.954(7), r(Se–C2)=1.836(11), r(C2–N)=1.162(9), ∠H1–C1–H2=110.6(6), ∠H2–C1–H2′=111.4(3), ∠H1–C1–Se=105.4(5), ∠H2–C1–Se=109.3(6), ∠C1–Se-C2=96.0(11), and ∠Se–C2–N=179.3(15). It was found from the rs structural parameters that the methyl group is at a staggered position with respect to the cyano group, the methyl group does not show C3v symmetry, the bond length of r(Se–C2) is much shorter than that of r(Se–C1), and the chain bond of Se–C2–N is linear.
Zygomycosis is an opportunistic fungal infection that affects the central nervous system (CNS). In this report, we present three cases of zygomycosis with CNS involvement. In two patients zygomycosis developed after neurosurgery, and in the third patient zygomycosis developed after bone marrow transplantation for leukemia. All patients developed persistent fever and neurological deficits. They presented with progressive cerebral infarction accompanied by hemorrhage. Intraoperative findings and histopathological examinations revealed that zygomycotic hyphae caused mycotic aneurysm, vasculitis, and venous occlusion.
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