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31.
32.
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis.  相似文献   
33.
It is well known that dendritic cells (DCs) are developed from the peripheral blood of mice when peripheral blood mononuclear cells (PBMCs) are cultured with GM-CSF. We have previously found that immature DCs are present in the blood even in humans. In the present study, we show that CD11c+ CD3- B220- cells in the mouse peripheral blood are immature DCs. The percentage of CD11c+ CD3- B220- cells in the (PBMCs) of normal mice ranges from 0.5 to 2.5%. The CD11c+ CD3- B220- cells in the PBMCs show dendrites, similar in shape to the CD11c+ CD3- B220- cells in the spleen, which are thought to be DCs definitely. However, they have practically no capacity to stimulate the proliferation of allogeneic T cells, and show a lower expression of MHC class II, B7-1 and B7-2 than CD11c+ CD3- B220- cells in the spleen. When the CD11c+ CD3- B220- cells in the PBMCs are cultured with GM-CSF, they show not only the potent ability to stimulate the proliferation of allogeneic T cells but also a higher expression of MHC class II, B7-1 and B7-2. Moreover, they migrate into the spleen when they are injected intravenously. These results suggest that CD11c+ CD3- B220- cells in the PBMCs are immature DCs, and that they migrate into the spleen, where they mature.  相似文献   
34.
Human rhabdomyosarcoma cells chronically infected with retroviruses were examined for their responses to human interferon (HuIFN-α). Production of baboon endogenous retrovirus (M7) from A204 cells and feline endogenous retrovirus (RD114) from RD114 cells and from subclone RD114-Cl cells in each case was highly sensitive to the antiviral action of HuIFN-α. However, the antiviral responses of the cells after interferon treatment against encephalomyocarditis (EMC) virus and vesicular stromatitis virus (VSV) were different for each cell strain used. In A204 cells, replications of EMC virus and VSV were sensitive to interferon, but resistant in RD114 and RD114-Cl cells. Both 2′-5′-oligo(A) (2–5A) synthetase and dsRNA-dependent protein kinase were markedly increased in A204 cells after HuIFN-α treatment but no significant increase was observed in RD114 and RD114-Cl cells. In all these cells, HuIFN-a efficiently induced an anti-cell fusion state which was determined by inhibition of syncytium formation induced by uv-inactivated Sendai virus. These results indicate that the mechanisms underlying the anti-retrovirus and the anti-cell fusion activities of interferon may be closely related, and that they are different from those of antiviral action against exogenous virus infections.  相似文献   
35.
Immunohistochemical localization of renin in renal tumors.   总被引:1,自引:0,他引:1       下载免费PDF全文
Immunoperoxidase staining for renin was performed with renal tumors, including juxtaglomerular (JG) tumor, Wilms' tumors, renal adenocarcinomas, renal oncocytomas, and cortical adenomas. Compared with the JG apparatus adjacent to the glomerulus, JG tumor cells were less darkly but diffusely stained for renin. One of five Wilms' tumors revealed more numerous renin-containing tumor cells than the adjacent renal cortex, whereas three of ten renal adenocarcinomas and two of three renal oncocytomas revealed only focally renin-positive tumor cell cytoplasms. None of six cortical adenomas were positive for renin. With available fresh tumor tissue, renin activity was studied by measuring newly formed angiotensin I by radioimmunoassay. JG tumor contained markedly elevated renin activity, whereas one Wilms' tumor and two renal adenocarcinomas contained no more than 2% of renin activity of the renal cortex, more than 50% of which was inactive renin. These findings suggest that the JG tumor elaborates enormous amounts of active renin, whereas other renal tumors produce lesser amounts of renin, more than half of which is inactive renin.  相似文献   
36.
We analyzed DNA from 63 Japanese men with either azoospermiaor severe oligospermia whose Y chromosomes were cytogeneticallynormal. A total of 16 loci were examined: 15 loci on the longarm between DYS7E and DYZ1, and the YRRM1 locus, a candidategene for the azoospermic factor, AZF. One patient with a perlcentricinversion of the Y chromosome was also included. We detectedmicro-deletions in ten individuals. The YRRM1 gene was Involvedin only three of them. The remaining seven patients showed deletionbetween DYS7C and DYS239 in common, indicating the presenceof at least one additional gene, deletion of which causes azoospermia.  相似文献   
37.
Summary Thickened ligamenta flava obtained from 14 patients with spinal canal stenosis were examined with special reference to type VI collagen. The characteristic histological finding in the thickened area was rupture of normal elastic fibre meshwork with resultant fibrosis which usually appeared hyaline. Using an immunohistological method, collagen types VI, I and III were found to be present in the hyaline matrix. Ultrastructural study revealed many microfilamentous structures of type VI collagen admixed in loosely packed, banded collagen fibres. With differential salt precipitation of pepsin-extracted collagen the existence of type VI collagen was confirmed by SDS-polyacrylamide gel electrophoresis analysis and Western blotting analysis using anti-type VI collagen antibody. Quantification of type VI collagen in pepsin-extracted crude collagen samples by an inhibition enzyme-linked immunosorbent assay showed an increasing amount of type VI collagen in the thickened ligamenta flava compared to the normal ligaments. Thus, increase of type VI collagen is the main contribution to the thickening of the ligamentum flavum. This may represent an adaptational and reparative process associated with disruption of elastic fibres.  相似文献   
38.
ABSTRACT: Human leukocyte antigen (HLA) genes are candidates for susceptibility genes in insulin-dependent diabetes mellitus (IDDM). Recently, the association of DR and DQ with IDDM has been reported, but the role of HLA-DP genes remains uncertain. To address the question, we analyzed the DPB1 gene of 20 Japanese IDDM patients and 30 control subjects using a combination of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis (PCR-RFLP method). DPB1*0501 was the most frequent allele both in Japanese patients and control subjects. There was no appreciable association between IDDM and the DPB1 allele in Japanese. The absence of association between IDDM and DP, in spite of the known association between this disease and both DR and DQ, suggests that the HLA locus (loci) telomeric to DP encodes susceptibility to IDDM.  相似文献   
39.
Several mutations of presenilin (PS)-1, 2 result in early onset Alzheimer disease. Using the yeast two-hybrid system, the interaction between PS2 loop domain and the C-terminal region of mu-calpain was previously identified. Calpain is a calcium dependent-protease and there are two isoforms, m-calpain and mu-calpain, which differ in the calcium concentration required for activation. m-Calpain needs about 10(-3) M calcium ions, whereas mu-calpain about 10(-5) M. When PS and calpain were separately expressed in COS cells by cDNA transfection and then combined in vitro, or both were co-transfected to be co-expressed in vivo in COS cells, PS1 and PS2 reduced the casein proteolysis activity of m-calpain but not that of mu-calpain. Some of the PS mutations related to Alzheimer disease decreased this inhibitory activity. On the other hand, PS1 was cleaved by m-calpain and mu-calpain at a different site from those already reported (constitutive cleavage or alternative cleavage). These results suggest a regulatory function of presenilin on the calpain system.  相似文献   
40.
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