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61.
Recent studies have suggested that some kinds of microbial infection may have a crucial role in the development of many diseases such as autoimmune diseases and certain types of cancer. It has been reported that some chronic infections, such as Chlamydia pneumoniae, and immunological dysfunctions are associated with age-related macular degeneration (AMD), a leading cause of blindness. To evaluate the association between systemic low-level inflammation induced by infection and AMD pathogenesis, we investigated whether intraperitoneal injection of lipopolysaccharide (LPS) can modulate the development of laser-induced choroidal neovascularization (CNV), a key feature of AMD. Contrary to our expectations, the sizes of CNV in mice with LPS pretreatment were approximately 65% smaller than those of the control mice. After LPS pretreatment, serum IL-10 concentration and IL-10 gene expression in peritoneal macrophages and in the posterior part of the eye increased. Peritoneal injection of anti-IL10 antibody reduced CNV suppression by LPS pretreatment. Moreover, adoptive transfer of the resident peritoneal macrophages from LPS-treated mice into control littermates resulted in an approximately 26% reduction in the size of CNV compared with PBS-treated mice. We concluded that CNV formation was suppressed by low-dose LPS pretreatment via IL-10 production by macrophages.  相似文献   
62.
In a murine model of acute fatal pneumonia, we previously showed that nasal immunization with a live-attenuated aroA deletant of Pseudomonas aeruginosa strain PAO1 elicited LPS serogroup-specific protection, indicating that opsonic Ab to the LPS O Ag was the most important immune effector. Because P. aeruginosa strain PA14 possesses additional virulence factors, we hypothesized that a live-attenuated vaccine based on PA14 might elicit a broader array of immune effectors. Thus, an aroA deletant of PA14, denoted PA14DeltaaroA, was constructed. PA14DeltaaroA-immunized mice were protected against lethal pneumonia caused not only by the parental strain but also by cytotoxic variants of the O Ag-heterologous P. aeruginosa strains PAO1 and PAO6a,d. Remarkably, serum from PA14DeltaaroA-immunized mice had very low levels of opsonic activity against strain PAO1 and could not passively transfer protection, suggesting that an antibody-independent mechanism was needed for the observed cross-serogroup protection. Compared with control mice, PA14DeltaaroA-immunized mice had more rapid recruitment of neutrophils to the airways early after challenge. T cells isolated from P. aeruginosa DeltaaroA-immunized mice proliferated and produced IL-17 in high quantities after coculture with gentamicin-killed P. aeruginosa. Six hours following challenge, PA14DeltaaroA-immunized mice had significantly higher levels of IL-17 in bronchoalveolar lavage fluid compared with unimmunized, Escherichia coli-immunized, or PAO1DeltaaroA-immunized mice. Antibody-mediated depletion of IL-17 before challenge or absence of the IL-17 receptor abrogated the PA14DeltaaroA vaccine's protection against lethal pneumonia. These data show that IL-17 plays a critical role in antibody-independent vaccine-induced protection against LPS-heterologous strains of P. aeruginosa in the lung.  相似文献   
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64.
Adult T cell leukemia (ATL) is a malignant disease characterized by tumorous proliferation of CD4+ T cells infected with retrovirus human T cell leukemia virus Type-I (HTLV-I) and concurs with an autoimmune disease and cancer due to attenuated immune response. In this study, we established ATL patient derived B-cell line TM-1 producing cancer-specific IgM antibodies, and further characterized its antigen specificity by establishing hybridomas fused with human-mouse origin hetero-myeloma cell line RF-S1. We established three hybridoma cell lines termed 2E12, 3E9, and 3E10, which continuously secreted human IgM antibodies. Immunohistochemical staining of formalin-fixed tissue section using antibodies secreted from these hybridomas showed that these antibodies specifically recognized tumor sites of human colon adenocarcinomas. Antibody produced from hybridoma 3E9 bound to some of leukemic cell lines, but not to normal human PBL, which was evidenced by the flow cytometric analysis, indicating that antibody produced from 3E9 recognizes cell surface antigen specifically expressed in the leukemic cells. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
65.
The effect was studied of retinoic acid (RA) on cell-cell adhesiveness in Ag8-1 cells, which are piling-up colony-forming cells cloned from a Syrian hamster kidney fibroblastic cell line BHK21/C13. From the piled-up part of the colonies grown with RA (10 microM), many cells were dissociated by mere shaking or pipetting. The dissociated cells soon adhered to and spread on plastic surfaces in the presence of RA. The number of cells per colony increased almost at the same rate in the presence or absence of RA. The effect of RA on the appearance of cells dissociable from colonies was noticeable above 0.1 microM, prominent from 1 to 10 microM, greater when added in the earlier stages of colony formation and negligible when added just before the dissociation assay. Single cells from the monolayer culture grown with RA (10 microM) had less tendency to aggregate than did those from the control culture. Cells from the colonies grown with RA adhered to and spread on a plastic dish for bacterial use, but control cells seldom adhered. These results indicate that RA decreases the cell-cell adhesiveness or suppresses the development of it but increases cell-substratum adhesiveness.  相似文献   
66.
Insulin-like growth factors (IGFs) are key regulators of development, growth, and longevity. In most vertebrate species including humans, there is one IGF-1 gene and one IGF-2 gene. Here we report the identification and functional characterization of 4 distinct IGF genes (termed as igf-1a, -1b, -2a, and -2b) in zebrafish. These genes encode 4 structurally distinct and functional IGF peptides. IGF-1a and IGF-2a mRNAs were detected in multiple tissues in adult fish. IGF-1b mRNA was detected only in the gonad and IGF-2b mRNA only in the liver. Functional analysis showed that all 4 IGFs caused similar developmental defects but with different potencies. Many of these embryos had fully or partially duplicated notochords, suggesting that an excess of IGF signaling causes defects in the midline formation and an expansion of the notochord. IGF-2a, the most potent IGF, was analyzed in depth. IGF-2a expression caused defects in the midline formation and expansion of the notochord but it did not alter the anterior neural patterning. These results not only provide new insights into the functional conservation and divergence of the multiple igf genes but also reveal a novel role of IGF signaling in midline formation and notochord development in a vertebrate model.  相似文献   
67.
68.

Aim

This study aimed to evaluate the treatment result of intensity-modulated radiation therapy (IMRT) in a large number of Japanese patients with prostate cancer.

Background

A total of 1091 patients with localized prostate cancer were recruited between March 2006 and July 2014. The patients were stratified into low- (n = 205 [18.8%]), intermediate- (n = 450 [41.2%]), high- (n = 345 [31.6%]), and very high-risk (n = 91 [8.3%]) groups according to the National Comprehensive Cancer Network classification. All patients were irradiated via IMRT at a dose of 74–78 Gy with or without androgen-deprivation therapy. The mean follow-up period was 50 months (range, 2–120 months).

Results

The biochemical failure-free rate (BFFR), the clinical failure-free rate, and the overall survival rate at the 5-year follow-up for all patients was 91.3%, 96.2%, and 99.1%, respectively. In univariate analysis, the prostate-specific antigen (PSA) levels (≤20 vs. >20 ng/ml) were significantly correlated with BFFR. A trend toward higher BFFR was noted in patients with a Gleason score (GS) of ≤7 than in patients with GS ≥8. In multivariate analysis, only PSA (≤20 vs. >20 ng/ml) was significantly correlated with BFFR. The cumulative incidence rate of gastrointestinal and genitourinary toxicity (≥grade 2) at the 5-year follow-up was 11.4% and 4.3%, respectively.

Conclusions

The findings of this study indicate that IMRT is well tolerated and is associated with both good long-term tumor control and excellent outcomes in patients with localized prostate cancer.  相似文献   
69.
Transglutaminase (TG) is an essential enzyme to catalyze cross-linking reactions of epidermal proteins. Recently, we biochemically characterized human skin TG orthologues for medaka (Oryzias latipes), a model fish. By genome editing, gene-modified fishes for the two orthologues were obtained, both of which lack the ordinal enzymes. These fish appeared to exhibit higher susceptibility to osmolality at the period of larvae.  相似文献   
70.
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