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891.
892.
Propagation of white spot syndrome virus (WSSV) was investigated in primary ovarian cultures from the kuruma shrimp Marsupenaeus japonicus. A WSSV strain, purified by sucrose density gradient centrifugation, was inoculated into 10-day-old primary ovarian cultures. WSSV infection induced marked cytopathic effect (CPE) on primary ovarian cells. Initially, virus-infected cells began to shrink 72 h post-inoculation, followed by the rounding of most cells which detached finally from flask surface. Electron microscopic observations clearly showed that the replication of WSSV occurred in nuclei of ovarian cells. Immunoblot analysis with antibodies against the WSSV envelope protein VP28 provided the evidence that the levels of WSSV antigens in culture supernatant gradually increased during the period between 24 and 120 h after virus inoculation. The results suggest that the use of primary ovarian cultures of the kuruma shrimp will facilitate characterization of the WSSV infection.  相似文献   
893.
894.
Immunosuppressive therapy and stem cell transplantation from an HLA-identical donor are the major effective treatments for severe aplastic anemia. However, treatments still need to be developed for patients who do not have a HLA-identical donor and have not shown a clinical response to immunosuppressive therapy. We herein report on 2 patients in whom this problem could be overcome by transplantation of HLA-mismatched umbilical cord blood from unrelated donors. Two Japanese patients with severe aplastic anemia underwent conditioning with fludarabine, cyclophosphamide, and low-dose total-body irradiation and then received transplants of umbilical cord blood. Engraftment of the three lineages occurred without problems. We conclude that umbilical cord blood transplantation with a reduced-intensity conditioning regimen of fludarabine, cyclophosphamide, and total-body irradiation for patients with aplastic anemia is a practical treatment and may be an attractive alternative for patients who does not have an HLA-identical donor and have shown no clinical response to immunosuppressive therapy.  相似文献   
895.
The periodontal ligament (PDL) is a fibrous connective tissue located between the tooth root and the alveolar bone. We previously demonstrated that a single cell-derived culture of primarily cultured PDL fibroblasts has the potential to construct an endothelial cell (EC) marker-positive blood vessel-like structure, suggesting that the fibroblastic lineage cells in ligament tissue could act as the endothelial progenitor cells (EPCs), which regenerate to construct a vascular system around the damaged ligament tissue. Moreover, we showed that EPC-like fibroblasts expressed not only EC markers but also smooth muscle cell (SMC) markers. Generally, an interaction between ECs and SMCs regulates blood vessel development and remodeling, and is required for the formation of a mature and functional vascular network. However, the mechanism underlying the SMC differentiation of the ligament-derived EPC-like fibroblasts remains to be clarified. In this study, we showed that suppression of fibroblast growth factor 1 (FGF-1)-induced extracellular signal-regulated kinase 1/2 (ERK1/2) signaling with the MAPK/ERK kinase (MEK) inhibitor U0126 completely abolished the FGF-1-induced proliferation of the ligament-derived EPC-like fibroblasts. In addition, U0126 treatment of FGF-1-stimulated ligament-derived EPC-like fibroblasts significantly induced the SMC differentiation of the cells. Thus, FGF-1-induced ERK1/2 signaling not only promoted the proliferation of the ligament-derived EPC-like fibroblasts, but also suppressed the SMC differentiation of the cells, suggesting that FGF-1 controls the construction of a vascular network around the ligament tissue by regulating the proliferation and SMC differentiation of the EPC-like cells through ERK-mediated signaling.  相似文献   
896.
PurposeGuidelines and systematic reviews frequently warn of inhaled corticosteroid (ICS)-induced glaucoma. However, most of the published studies deny it.MethodsWe performed a systematic review of randomized, cohort, nested-case control, cross-sectional studies by using Meta-analyses of Observational Studies in Epidemiology statement. Four major databases, PubMed, EMBASE, Cochrane Search Manager, and the Web of Science Core Collection as well as meta-analysis were used. Studies comparing incidence, prevalence and intraocular pressure (IOP) between patients who were treated with and without ICSs were included. A random-model meta-analysis was performed using the inverse variance method.ResultsOut of 623 studies screened, 18 with 31,665 subjects were finally included. No significant difference between the 2 groups was observed for crude glaucoma incidence (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.86–1.04; P = 0.26; I 2 = 0%; P for heterogeneity = 0.57) as a primary endpoint, adjusted glaucoma incidence (OR, 0.90; 95% CI, 0.65–1.24; P = 0.64), crude prevalence (OR, 1.82; 95% CI, 0.23–14.19; P = 0.57), adjusted prevalence (OR, 1.22; 95% CI, 0.50–2.96; P = 0.66), IOP change during ICS treatment (mean difference [MD] +0.01 mmHg; 95% CI, −0.19–0.20; P = 0.95), and single measurement IOP (MD +0.37 mmHg; 95% CI, −0.24–0.97; P = 0.23). Time-to-event analysis for glaucoma development as one of the secondary endpoints (adjusted hazard ratio, 0.52; 95% CI, 0.28–0.96) suggested a reverse association between ICS and glaucoma.ConclusionsThe ophthalmological side effects of ICSs, such as glaucoma and intraocular hypertension, should not be exaggerated.Trial RegistrationUniversity Hospital Medical Information Network Center Clinical Trial Registry Identifier: UMIN000040351  相似文献   
897.
Inflammatory bowel disease (IBD) is a chronic inflammatory disorder in the intestine, and the dysfunction of intestinal epithelial barrier (IEB) may trigger the onset of IBD. Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor that has been implicated in the tissue-protective effect in the skin and lung. We found that SLPI was induced in lipopolysaccharides-treated colon carcinoma cell line and in the colon of dextran sulfate sodium (DSS)-treated mice. SLPI-deficient mice were administered DSS to induce colitis and sustained severe inflammation compared with wild-type mice. The colonic mucosa of SLPI-deficient mice showed more severe inflammation with neutrophil infiltration and higher levels of proinflammatory cytokines compared with control mice. Moreover, neutrophil elastase (NE) activity in SLPI-deficient mice was increased and IEB function was severely impaired in the colon, accompanied with the increased number of apoptotic cells. Importantly, we demonstrated that DSS-induced colitis was ameliorated by administration of protease inhibitor SSR69071 and recombinant SLPI. These results suggest that the protease inhibitory activity of SLPI protects from colitis by preventing IEB dysfunction caused by excessive NE activity, which provides insight into the novel function of SLPI in the regulation of gut homeostasis and therapeutic approaches for IBD.  相似文献   
898.
The pathogenicity of white spot syndrome virus (WSSV) for the red swamp crawfish (Procambarus clarkii) was investigated after infection by intramuscular (i.m.) injection and oral route. The cumulative mortality of crawfish injected i.m. with WSSV reached 100% in 5 days. After oral feeding WSSV-infected kuruma shrimp (Penaeus japonicus) muscle tissues to the crawfish the cumulative mortality of this host reached 100% in 11 days. On reinfection trials, all the crawfish fed WSSV-infected crawfish muscle tissues died in 9 days. All the shrimp injected with a filtrate of infected crawfish heart tissues died in 12 days with typical signs of white spot syndrome (WSS). Electron microscopy clearly demonstrated that WSSV propagated in the cells of the crawfish midgut. This study showed that the red swamp crawfish can be used as alternative experimental host in the study of WSSV.  相似文献   
899.
The associations between the efficacy of IgG reagents and the FCGRIIIa‐158V/F polymorphism (rs396991) have been investigated. Although the genotype frequencies in healthy Japanese have been reported, those have varied, as one study reported that the proportions of V/V, V/F, and F/F were 59.1%, 38.6%, and 2.3%, respectively, while another study found that they were 4%, 44%, and 52%, respectively. However, there are no known investigations of the association between the antibody‐dependent cellular cytotoxicity (ADCC) activity of adalimumab (ADA), an IgG reagent, in combination with FcγRIIIa and the polymorphism. In this study, we analyzed healthy Japanese to clarify genotype frequency using a direct sequence method. In addition, we examined the association between the ADA‐mediated ADCC activity and the polymorphism. Our results showed that the frequencies of the V/V, V/F, and F/F genotypes in healthy Japanese were 9.2%, 39.8%, and 51.0%, respectively. The average activity of ADA‐mediated ADCC was 25.0%, 19.0%, and 13.3% in the V/V, V/F, and F/F genotypes, respectively. Then, the ADCC activity of V/V was significantly higher than that of F/F (p < 0.05) in therapeutic concentration. The differences in therapeutic effect of ADA among individuals can be explained, in part, by ADCC activity via the FCGRIIIa‐158V/F polymorphism.  相似文献   
900.
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