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61.
Two cell lines designated IC KMS and D KMS were established from human adenovirus type 12 induced tumors of C3Hf/OK mouse. The cell lines retained the characteristics of the original tumor i.e., production of numerous C type and intracisternal A-type particles, integration of Adl2 El region DNA and amplification of the myc gene family. Chromosomal analysis revealed chromosome aberrations in both IC KMS and D KMS cells. The modal chromosome number of IC KMS cells was 54 and that of D-KMS cells was 48. Metacentric chromosomes and mini-chromosomes were found. Trisomy of chromosome 3, 7 and 12 was seen frequently in D KMS cells. Although DNA aneuploidy was revealed by flow cytometry, the DNA indices of these cells showed no relation to the copy number of integrated Adl2 DNA. These cells have been propagated by serial culture during the past 17 months. Production of endogenous virus particles is a unique characteristic of IC KMS and D KMS cells. These cell lines would be useful materials for examining the contribution of Adl2 carcinogenesis to activation of endogenous virus particles, and also the correlation between Adl2 carcinogenesis and cancer related genes. Acta Pathol Jpn 42: 242-248, 1992.  相似文献   
62.
Cationic polymerization of styrene in the presence of 1-(p-methoxybenzyl)tetrahydrothiophenium hexafluoroantimonate ( 3 ) as an efficient cationic initiator was investigated. 3 was synthesized in an excellent yield by the reaction of p-methoxybenzyl bromide with tetrahydrothiophene and the subsequent exchange of bromide ions for hexafluoroantimonate ions. In the polymerization of styrene, 3 acted as a potent thermally latent initiator which initiates the polymerization at a slightly higher temperature than room temperature, although no polymerization occurs at room temperature for 30 min. 3 is a much more active initiator than the previously reported benzylsulfonium salt 1 . The enhanced activity of 3 was also confirmed in the polymerization of glycidylb phenyl ether.  相似文献   
63.
Four cases of Ischemic enterocolitis without arterio–occlusive lesion were described. Three cases were associated with sigmoid colon carcinomas. Ischemic lesions developed anal to the carcinomas in two cases, and oral to sigmoidostomy to relieve intestinal obstruction by carcinoma in one case. One other case was associated with inguinal hernia. Grossly, ischemic lesions involved relatively short intestinal segments, and the ischemic colonic lesions were not related to teniae coli. Extensive veno–occlusive lesions were discovered in a case of ischemic stricture of the ileum, which had been incarcerated in the right inguinal hernia. Reversible mechanical occlusion of the intestinal vessels caused by transient or recurrent intestinal strangulation is the most probable cause of these ischemic lesions., ACTA PATHOL. JPN. 33: 249–256, 1983.  相似文献   
64.
The character of the antibody response in the rabbit to Salmonella typhimurium somatic (O) antigen was similar to the response to each of several serotypes of Shigella flexneri O antigens, namely a predominance of production of immunoglobulin M (IgM) antibody. Lipopolysaccharide protein (LPSP) and lipopolysaccharide (LPS) fractions of Salmonella O antigen differed significantly in both quantitative and qualitative aspects of their immunogenicity. LPSP elicited high levels of agglutinins and also induced the production of a significant amount of immunoglobulin G (IgG) antibody at a late period. LPS antigen elicited low levels of agglutinins which were exclusively IgM antibody. These results suggested that the chemical nature of the antigen is one important factor in the determination of the character of the antibody response. Further, it is suggested that the protein moiety of the O antigen complex is a carrier active in allowing induction of early IgM and of late IgG antibodies; in contrast, the lipid moiety may compete with this action of the carrier protein, thereby suppressing IgG antibody in the primary stage of the antibody-forming process.  相似文献   
65.
The effects of different molecular weights of hyaluronic acid (HA), a major component of extracellular matrix, on gap junctional intercellular communication (GJIC) in normal human dermal fibroblasts (NHDF cells) were investigated. NHDF cells were cultured for 4 days with different molecular weights of HA and then the extent of GJIC was assessed by the scrape-loading dye transfer method, using Lucifer yellow. The area of dye transfer was greater in the dishes coated with HA than in those to which HA was added. Thus, NHDF cells cultured on surfaces coated with high molecular weight (HMW) HA (MW, 800 kDa) showed greatly enhanced GJIC. Furthermore, another aim of this study was to evaluate the effects of different molecular weights of HA on the production of FGF-2 and KGF, because both are important cytokines produced by NHDF cells. When FGF-2 and KGF cultured levels of cell extracts and media were determined by ELISA, both levels were significantly enhanced when cells were grown on plates coated with HMW HA. This finding indicated that the function of gap junction channels in NHDF cells grown on plates coated with HMW HA may promote the biosynthesis of growth factors such as FGF-2 and KGF.  相似文献   
66.
We have previously shown that tumor necrosis factor-α (TNF-α), which is an important angiogenesis-related factor, was over-secreted in male BALB/c mice under social isolation stress as compared with the control, and closely associated with a remarkable elevation of tumor invasion and metastasis of colon 26-L5 carcinoma cells. In the present study, we explored the effect of isolation stress on the angiogenesis caused by colon 26-L5 carcinoma cells in vivo and in vitro. Social isolation lead to the enhancement of tumor growth after intrahepatic implantation with a fragment of colon 26-L5 tumor. Angiogenic response (number of vessels oriented towards tumor mass) and tumor growth (size) were significantly increased in the socially isolated mouse relative to that in the group-housed mice. Furthermore, higher protein level of hepatic TNF-α was found in the stressed mice than that in the control. Expression of mRNA for vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were also elevated in the tumor regions and liver tissues of the stressed mice in comparison with that in group-housed mice. On the other hand, hepatic sinusoidal endothelial (HSE) cells treated with TNF-α exhibited a marked promotion of the migration, invasion, expression of mRNA for matrix metalloproteinase (MMP)-9, and tube-like formation, but no cytotoxicity against the cells in vitro. The above data suggest that the social isolation stress augmented the tumor-induced angiogenesis probably by up-regulating the angiogenesis-related factors, including TNF-α, VEGF and HGF, and consequently mediating the functions of endothelial cells such as migration, invasion, and tube-like formation.  相似文献   
67.
Poly-L-lactic acid (PLLA) is a widely used promising material for surgical implants such as tissue-engineered scaffolds. In this study, we aimed to determine the in vivo effect of PLLA plates on the cellular function of subcutaneous tissue in the two mouse strains, BALB/cJ and SJL/J, higher and lower tumorigenic strains, respectively. Gap-junctional intercellular communication (GJIC) and the expression of connexin 43 (Cx43) protein were significantly suppressed, whereas the secretion of transforming growth factor-beta 1 (TGF-beta 1) level was significantly increased in PLLA-implanted BALB/cJ mice compared with BALB/cJ controls. However, no significant difference in TGF-beta 1 secretion was observed between the SJL/J-implanted and SJL/J control mice. We found for the first time that a significant difference was observed between the two strains; thus, the PLLA increased the secretion of TGF-beta 1 and suppressed the mRNA expression of Cx43 at the earlier stage after implantation into the higher-tumorigenic strain, BALB/cJ mice. This novel mechanism might have a vital role in the inhibition of GJIC and promote the tumorigenesis in BALB/cJ mice.  相似文献   
68.
A modified SiO2 was prepared by reacting SiO2 with Cl2Si(CH3)2 in toluene, on which methylaluminoxane (MAO) was supported to obtain a catalyst precursor. The mixture of the precursor and Cp2ZrCl2 (Cp: cyclopentadienyl) gave polyethylene in a high yield even by using common trialkylaluminiums as cocatalyst. Surprisingly, the MAO-free catalyst system composed of the modified SiO2 and Cp2ZrCl2 was also found to be activated by common trialkylaluminiums.  相似文献   
69.
Recently it has been reported that patients with ulcerative colitis (UC) often have thymus abnormalities, although the precise mechanisms which induce those abnormalities remain unclear. We have examined the effect of serum fractions from patients with UC and other colonic diseases on mouse thymus to clarify the possible existence of factors which have thymus growth activity. These fractions were separated from sera of patients with UC by gel filtration and anion exchange high performance liquid chromatography. In mice given UC serum fractions; (i) remarkable increases in weight and total cell number of the thymus were observed from day 4 to day 9; (ii) a significant increase in the number of peanut agglutinin (PNA)+ thymus cells was demonstrated using flow cytometry on day 9; (iii) on quantitative analysis of surface antigens the percentage of Lyt-2+ thymus cells decreased and that of L3T4+ thymus cells increased remarkably on day 13; the number of bright Thy-1.2+ cells and of dull Lyt-1+ cells increased. In contrast, the serum fractions from patients with other colonic diseases and from normal persons caused little change in mouse thymus throughout the study. The results suggest that factors fractionated from the serum of patients with UC disturb intra-thymic T cell maturation and enhance the proliferation of thymus cells.  相似文献   
70.
The inhibitory effect of an antiserum to surface protein P50 of Babesia gibsoni on the growth of the parasite was determined with severe combined immunodeficiency mice given canine red blood cells. The antiserum to the recombinant P50 protein significantly inhibited the parasite growth, indicating that P50 might be a useful vaccine candidate.  相似文献   
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