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151.
152.
Ogawa A Murakami C Kamisuki S Kuriyama I Yoshida H Sugawara F Mizushina Y 《Bioorganic & medicinal chemistry letters》2004,14(13):3539-3543
A new isochroman derivative named pseudodeflectusin was isolated from a culture broth of Aspergillus pseudodeflectus. The structure was determined by spectroscopic means as 9-hydroxy-7-methyl-2-(methylethylidine)-furano[3,2-H]isochroman-3-one. This compound exhibited cytotoxicity for several human cancer cell lines from the stomach (NUGC-3), cervix (HeLa-S3), and peripheral blood (HL-60), but did not affect those from the lung (A549) or colon (DLD-1). The LD50 value of this compound for HL-60 cells was 39 microM. 相似文献
153.
154.
Mitochondria and autoimmunity in primary biliary cirrhosis 总被引:5,自引:0,他引:5
Primary biliary cirrhosis is an enigmatic autoimmune liver disease that predominantly affects women and is characterized by antimitochondrial antibodies and specific destruction of small bile ducts. Interestingly, patients with this disease not only have high titer antibodies to mitochondria, but also highly directed, liver-specific CD4 and CD8 cells directed at the same mitochondrial autoantigens. These mitochondrial autoantigens are all members of the 2-oxo dehydrogenase complex family and include the E2 component of pyruvate dehydrogenase as the major autoantigen. Moreover, the epitopes recognized by CD4, CD8 T cells and autoantibody, are all directed within the same region, namely the lipoyl domain of pyruvate dehydrogenase complex-E2. All cells in the body have mitochondria but there appear to be specific destruction of biliary cells. We believe that this specific destruction is secondary to a highly directed mucosal response that focuses on biliary cells because of the involvement of a polymeric immunoglobulin receptor, the presence of immunoglobulin A in mucosal secretions, and the unique apoptotic properties of biliary epithelium. 相似文献
155.
CLIP-170 family proteins regulate microtubule plus end dynamics. Two reports published in this issue of Developmental Cell show that Bik1 and tip1p, the CLIP-170-like proteins of budding and fission yeast, are carried to microtubule plus ends by kinesin motor proteins. These findings indicate a complex interplay between microtubule-associated proteins and suggest a novel mechanism by which kinesin proteins stabilize microtubules. 相似文献
156.
Uno K Mitsuishi Y Tanigawa M Okuno K Hirai N Mizutani Y Saotome H Fujiwara H Kishida T 《Cancer immunology, immunotherapy : CII》2003,52(1):33-40
The induction of interleukin-12 (IL-12) responsiveness in T cells depends on T cell receptor (TCR) triggering, and is regarded as a parameter of recently TCR-sensitized T cells. Here, we investigated whether IL-12 responsiveness could be detected in freshly prepared T cells from tumor-bearing patients, and if so whether such patients exhibited additional immunological parameters related to IL-12 responsiveness. CD4(+) and CD8(+) T cell populations from an appreciable proportion of tumor-bearing patients exhibited high levels of IL-12 responsiveness as evaluated by IL-12-stimulated interferon-gamma (IFN-gamma) production. T cell populations with high IL-12 responsiveness were observed in the group of patients with moderate to large tumor mass or tumor metastases rather than in patients with small tumors. The frequency of such a T cell population was also lower in post-surgery tumor-free patients, showing the correlation between IL-12 responsiveness and the presence of a certain extent of tumor burden. More importantly, a higher incidence of IL-12 responsiveness was observed in tumor-bearing patients exhibiting detectable plasma IL-12 levels, and correlated with IL-18 responsiveness. T cell IL-12 and IL-18 responsiveness is induced by TCR triggering and subsequent IL-12 stimulation respectively. Furthermore, TCR-triggered T cells stimulate antigen-presenting cells (APC) to produce IL-12. Therefore, the present observations suggest that an immune response loop from TCR sensitization to the induction of IL-12/IL-18 responsiveness via IL-12 production operates in tumor-bearing patients, particularly in those with relatively large tumor burdens. 相似文献
157.
Yoshida H Katayose Y Unno M Suzuki M Kodama H Takemura S Asano R Hayashi H Yamamoto K Matsuno S Kudo T 《Cancer immunology, immunotherapy : CII》2003,52(2):97-106
4-1BB ligand (4-1BBL), a member of the tumor necrosis factor (TNF) superfamily, interacts with 4-1BB (CDw137) expressed on activated T cells and delivers a costimulatory signal for T cell activation and growth. Various studies have demonstrated a role for murine 4-1BB in immune function, but relatively few investigations of human 4-1BB have been conducted. Here we report on the construction of a recombinant E1/E3-deleted adenovirus encoding human 4-1BBL (Ad4-1BBL) and its stimulation of antitumor immunity. Ad4-1BBL was able to efficiently infect several human adenocarcinoma cell lines and induce 4-1BBL expression on the cell surface within 24 h, this enhancing the antitumor activity not only of lymphokine-activated killer cells with a T cell phenotype (T-LAK) but also naive peripheral blood mononuclear cells (PBMC). This antitumor activity with T-LAK cells was further enhanced by addition of bispecific antibody (BsAb; anti-MUC1xanti-CD3). Cocultivation of Ad4-1BBL-infected tumor cells with either T-LAK cells or PBMC resulted in significant elevation of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), and granulocyte-macrophage colony-stimulating factor (GM-CSF) production. Furthermore, remarkable tumor growth inhibition was observed in cholangiocarcinoma-grafted severe combined immunodeficient (SCID) mice to which Ad4-1BBL and T-LAK cells were administered when tumor size exceeded 5 mm in diameter. These results provide strong evidence in support of the efficacy of adenovirally delivered 4-1BBL for genetic immunotherapy of cancer. 相似文献
158.
Recombinant bovine herpesvirus-1 expressing p23 protein of Cryptosporidium parvum induces neutralizing antibodies in rabbits 总被引:5,自引:0,他引:5
Takashima Y Xuan X Kimata I Iseki M Kodama Y Nagane N Nagasawa H Matsumoto Y Mikami T Otsuka H 《The Journal of parasitology》2003,89(2):276-282
In order to develop a vaccine against cryptosporidiosis in cattle, we constructed a recombinant bovine herpesvirus-1 (BHV-1) expressing an immunodominant surface protein, p23, of Cryptosporidium parvum sporozoites. In the recombinant virus, the p23 gene under the control of a CAG promoter and a gene coding for an enhanced green fluorescent protein were integrated into the gG gene of BHV-1. Despite a low frequency of homologous recombination, cloning of the recombinants was easy because of the specific fluorescence of the plaques formed by recombinants. These plaques were among the plaques of the nonfluorescent parental virus. All clones selected for fluorescence also contained the p23 gene. In MDBK cells infected with the recombinant BHV-1, the antibody against the p23 protein recognized the p23 protein as an approximately 23-kDa specific band in Western blotting analysis. Rabbits immunized with the recombinant produced IgG against the p23 protein. It was also demonstrated that the sera of immunized rabbits reduced infection of C. parvum sporozoites in HCT-8 cells. The serum of an immunized rabbit reduced infection compared with the normal rabbit serum control. These results indicate that the recombinant BHV-1 induces neutralizing antibodies in rabbits. 相似文献
159.
Macrophage-tropic simian/human immunodeficiency virus chimeras use CXCR4, not CCR5, for infections of rhesus macaque peripheral blood mononuclear cells and alveolar macrophages 下载免费PDF全文
Igarashi T Donau OK Imamichi H Dumaurier MJ Sadjadpour R Plishka RJ Buckler-White A Buckler C Suffredini AF Lane HC Moore JP Martin MA 《Journal of virology》2003,77(24):13042-13052
After the nearly complete and irreversible depletion of CD4(+) T lymphocytes induced by highly pathogenic simian/human immunodeficiency virus chimeric viruses (SHIVs) during infections of rhesus monkeys, tissue macrophages are able to sustain high levels (>10(6) viral RNA copies/ml) of plasma viremia for several months. We recently reported that the virus present in the plasma during the late macrophage phase of infection had acquired changes that specifically targeted the V2 region of gp120 (H. Imamichi et al., Proc. Natl. Acad. Sci. USA 99:13813-13818, 2002); some of these SHIV variants were macrophage-tropic (M-tropic). Those findings have been extended by examining the tropic properties, coreceptor usage, and gp120 structure of five independent SHIVs recovered directly from lymph nodes of late-stage animals. All of these tissue-derived SHIV isolates were able to infect alveolar macrophages. These M-tropic SHIVs used CXCR4, not CCR5, for infections of rhesus monkey PBMC and primary alveolar macrophages. Because the starting highly pathogenic T-tropic SHIV inoculum also utilized CXCR4, these results indicate that the acquisition of M-tropism in the SHIV-macaque system is not accompanied by a change in coreceptor usage. Compared to the initial T-tropic SHIV inoculum, tissue-derived M-tropic SHIVs from individual infected animals carry gp120s containing similar changes (specific amino acid deletions, substitutions, and loss of N-linked glycosylation sites), primarily within the V1 and/or V2 regions of gp120. 相似文献
160.
Characterization of hydrogen peroxide removal reaction by hemoglobin in the presence of reduced pyridine nucleotides 总被引:1,自引:0,他引:1
Hydrogen peroxide removal rates by hemoglobin were enhanced in the presence of reduced pyridine nucleotides. The species which had the activity to oxidize pyridine nucleotides was purified from human blood and identified as hemoglobin A. Hydrogen peroxide removal rates by hemoglobin A without reduced pyridine nucleotides at 0.2 mM hydrogen peroxide were 0.87+/-0.11 micromol/s/g hemoglobin, and the removal rates using 0.2 mM NADH and NADPH were 2.02+/-0.20 and 1.96+/-0.31 micromol/s/g hemoglobin, respectively. We deduced that the removal reaction by hemoglobin included formations of methemoglobin and the ferryl radical and reduction of the latter with pyridine nucleotides. The hydrogen peroxide removal ability by hemoglobin was less than that by catalase but was larger than that by glutathione peroxidase-glutathione reductase system at 0.2 mM hydrogen peroxide. Under acatalasemic conditions, it was suggested that NAD(P)H were important factors to prevent the oxidative degradation of hemoglobin. 相似文献