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151.
As serodiagnosis is the easiest way of diagnosing a disease, the utility of Mycobacterium leprae-derived major membrane protein-II (MMP-II), one of the immuno-dominant antigens, in the serodiagnosis of leprosy was examined. The percent positivity by an enzyme-linked immunosorbent assay for anti-MMP-II antibody was 82.4% for multi-bacillary leprosy, and the specificity of the test was 90.1%. For pauci-bacillary leprosy where cell-mediated immunity predominates, 39.0% showed positive results. These percentage values were significantly higher than these values obtained for existing phenolic glycolipid-I based methods, suggesting that MMP-II antibody detection would facilitate the diagnosis of leprosy.  相似文献   
152.
Aluminum hydroxide gel (Al-gel), which is used as an adjuvant, can absorb macromolecules. We investigated the applicability of Al-gel to the sustained release of follicle-stimulating hormone (FSH) as a simplified method of superovulation (SOV) in rabbits. The responsiveness of rabbits to SOV by a single injection of FSH dissolved in Al-gel suspension (3.2 mg Al/ml) and in 10% (w/v) polyvinylpyrrolidone (PVP), and by multiple injections of FSH in saline was examined. The numbers of total and fertilized eggs recovered from rabbits treated with FSH in Al-gel (40.5 and 26.3, respectively) were similar to multiple injections (47.4 and 28.6, respectively) and were significantly greater (P < 0.05) than single injection of FSH with PVP (17.3 and 11.5, respectively). We also compared the plasma FSH levels of rabbits which were induced SOV by multiple or a single injection of Al-gel. Al-gel provided sustained release of FSH to the blood stream at a high enough dose for SOV. Moreover, the developmental competence of the pups of DNA-injected embryos from rabbits treated with a single injection of FSH mixed with Al-gel (18%) was similar to that of DNA-injected embryos, recovered from rabbits treated with FSH dissolved in saline (21%). Two transgenic pups were obtained from embryos recovered from rabbits by a single injection of FSH with Al-gel. These results indicate that a single injection of FSH with Al-gel is an effective method for SOV of rabbit and that this technique is applicable to research requiring large numbers of rabbit embryos such as the production of transgenic rabbits.  相似文献   
153.
Ichthyological Research - The new snailfish Paraliparis variabilidens is described from a single specimen collected between 1,462 and 1,562&nbsp;m depth in the northern part of the Suruga...  相似文献   
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155.
Posttranslational modifications regulate the function and stability of proteins, and the immune system is able to recognize some of these modifications. Therefore, the presence of posttranslational modifications increases the diversity of potential immune responses to a determinant antigen. The stimulation of tumor-specific CD4+ helper T lymphocytes (HTLs) is considered important for the production of anti-tumor antibodies by B cells and for the generation and persistence of CD8+ cytotoxic T lymphocytes, and in some instances, HTLs can directly reduce tumor cell growth. Identification of MHC class II-restricted peptide epitopes from tumor-associated antigens including those generated from posttranslational protein modifications should enable the improvement of peptide-based cancer immunotherapy. We describe here an MHC class II binding peptide from the tumor protein p53, which possesses an acetylated lysine at position 120 (p53110-124/AcK120) that is effective in eliciting CD4+ T cell responses specific for the acetylated peptide. Most importantly, the acetylated peptide-reactive CD4 HTLs recognized the corresponding naturally processed posttranslational modified epitope presented by either dendritic cells loaded with tumor cell lysates or directly on tumors expressing p53 and the restricting MHC class II molecules. Treatment of tumor cells with a histone deacetylase inhibitor augmented their recognition by the p53110-124/AcK120-reactive CD4+ T cells. These findings prove that the epitope p53110-124/AcK120 is immunogenic for anti-tumor responses and is likely to be useful for cancer immunotherapy.  相似文献   
156.
Foamy viruses belong to the genus Spumavirus of the family Retroviridae and have been isolated from many mammalian species. It was reported that simian foamy viruses (SFVs) have co-evolved with host species. In this study, we isolated four strains (WK1, WK2, AR1 and AR2) of SFV (named SFVjm) from Japanese macaques (Macaca fuscata) in main island Honshu of Japan. We constructed an infectious molecular clone of SFVjm strain WK1, termed pJM356. The virus derived from the clone replicated and induced syncytia in human (human embryonic kidney 293T cells), African green monkey (Vero cells) and mouse cell lines (Mus dunni tail fibroblast cells). Phylogenetic analysis also revealed that these four SFVjm strains formed two distinct SFVjm clusters. SFVjm strains WK1 and WK2 and SFV isolated from Taiwanese macaques (Macaca cyclopis) formed one cluster, whereas strains AR1 and AR2 formed the other cluster with SFV isolated from a rhesus macaque (Macaca mulatta).  相似文献   
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158.
Echinococcus granulosus sensu stricto is a cosmopolitan parasite causing cystic echinococcosis in humans and livestock. Recent molecular phylogeographic studies suggested the rapid dispersal of the parasite by the anthropogenic movement of domestic animal hosts. In the present study, genetic polymorphism of E. granulosus s. s. in the Middle East, where the domestication started, was investigated to validate the dispersal history of the parasite. Thirty-five and 26 hydatid cysts were collected from Iran and Jordan, respectively, and mitochondrial cytochrome c oxidase subunit I (cox1) gene was sequenced. Chinese and Peruvian specimens were also analyzed for comparison. Haplotype network analysis demonstrated the existence of a common haplotype EG01 in all populations. Although EG01 and its one-step neighbors were the majority in all regions, most of the neighboring haplotypes were unique in each locality. Haplotype diversity was high but nucleotide diversity was low in Iran, Jordan and China. Both diversities were lowest and only a few haplotypes were found in Peru. Neutrality indices were significantly negative in Iran, Jordan and China, and positive but not significant in Peru. Pairwise fixation index was significant for all pairwise comparisons, indicating genetic differentiation among populations. These results suggest a evolutionary history of E. granulosus s. s. in which a genetic subgroup including EG01 was selected at the dawn of domestication, and then it was rapidly dispersed worldwide through the diffusion of stock raising. To approach the origin of the ancestral strain, extensive sampling is needed in many endemic regions. To evaluate the hypothetical evolutionary scenario, further study is needed to analyze specimens from diverse host species in wider regions.  相似文献   
159.
160.
Mutations in the mitochondrial PTEN-induced kinase 1 (Pink1) gene have been linked to Parkinson disease (PD). Recent reports including our own indicated that ectopic Pink1 expression is protective against toxic insult in vitro, suggesting a potential role for endogenous Pink1 in mediating survival. However, the role of endogenous Pink1 in survival, particularly in vivo, is unclear. To address this critical question, we examined whether down-regulation of Pink1 affects dopaminergic neuron loss following 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the adult mouse. Two model systems were utilized: virally delivered shRNA-mediated knockdown of Pink1 and germ line-deficient mice. In both instances, loss of Pink1 generated significant sensitivity to damage induced by systemic MPTP treatment. This sensitivity was associated with greater loss of dopaminergic neurons in the Substantia Nigra pars compacta and terminal dopamine fiber density in the striatum region. Importantly, we also show that viral mediated expression of two other recessive PD-linked familial genes, DJ-1 and Parkin, can protect dopaminergic neurons even in the absence of Pink1. This evidence not only provides strong evidence for the role of endogenous Pink1 in neuronal survival, but also supports a role of DJ-1 and Parkin acting parallel or downstream of endogenous Pink1 to mediate survival in a mammalian in vivo context.  相似文献   
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