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61.
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Tumor-specific peptide-pulsed dendritic cells (DC) were administered via different routes to a group of patients with head and neck cancers. The migration and homing patterns of such antigen-stimulated cells was carefully studied employing single photon emission computed tomography (SPECT). The DC administered directly into the nasal submucosa quickly migrated very rapidly to the regional neck lymph nodes in the neck. However, after inoculation of the cells into the palatine tonsils, the DCs remained close to the site of administration and did not migrate to the regional lymph nodes or to other mucosal regions. After nasal submucosal administration of the DC, tumor-antigen-specific cytotoxic T cells were detected in the ipsilaterals but not in the contra lateral lymph nodes. These results suggest that after antigen processing, the regional lymph nodes serve as inductive sites for development of mucosal immune responses and for induction of memory cells during the local immunological responses in the nasopharyngeal-associated lymphoid tissue in man.  相似文献   
63.
HIV-1 evolution in the envelope gene (env) was analyzed in four asymptomatic antiretroviral therapy na?ve patients with typical and slow disease progression rates. In typical progressors, viral populations were monophyletic and two distinct evolutionary patterns were observed. In one patient, HIV-1 evolution displayed a strong temporal structure similar to the consistent pattern previously described. In the other, viral evolution displayed a lack of temporal structure with no increase in genetic heterogeneity and divergence over time. In slow progressors, several clades were observed in viral populations. However, analysis within the major sub-population revealed the same two evolutionary patterns described for typical progressors. Synonymous and non-synonymous substitution rate analyses indicated that positive selection was the major force driving HIV-1 evolution in viral populations with temporal structure, while evolution in viral populations with an atemporal structure was dominated by genetic drift and purifying selection. These results support the existence of distinct patterns of env evolution in untreated HIV-1-infected patients.  相似文献   
64.
BACKGROUND: We hypothesized that the S100A8/A9 complex is effective in the suppression of acute inflammatory changes. METHODS: To clarify such a functional role of the S100A8/A9 complex in acute inflammatory disorder, the complex purified from human leukocytes (approx. 1 mg) was intraperitoneally injected into rats 1.0 or 3.5 h after an injection of lipopolysaccharide (LPS). RESULTS: The serum concentrations of interleukin-6 (IL-6) and nitric oxide (NOx) were significantly decreased in the treated rats. Conversely, when anti-S100A8/A9 complex IgG was injected into the tail blood vessel of a rat 1.0 h after the injection of LPS, the serum concentration of IL-6 increased slightly, indicating that the antibody immunoregulatorily blocked the activity of the complex as an anti-inflammatory protein in vivo. In addition, the S100A8/A9 complex bound non-specifically with interleukin-1beta (IL-1beta), IL-6 and TNF-alpha in vitro, suggesting that the complex could bind with these cytokines in vivo. A large number of endogenous S100A8/A9 complex-positive cells that accumulated in the inflamed region in the liver 6 h after the injection of LPS were microscopically observed, while apparent inflammatory changes were not found microscopically in other organs, such as the kidney, lung and spleen. In rats treated with the S100A8/A9 complex, neither acute inflammatory changes nor S100A8/A9 complex-positive cells were also observed microscopically in the liver tissue. CONCLUSIONS: These findings suggest that the S100A8/A9 complex indirectly suppresses the overproduction of NOx from activated neutrophils and/or macrophages by neutralizing the activity of pro-inflammatory cytokines. Thus, the S100A8/A9 complex may play an important role in the suppression of acute inflammation by modulating the vital activity of pro-inflammatory cytokines in vivo.  相似文献   
65.
European Journal of Orthopaedic Surgery & Traumatology - Combined anteversion (CA) technique (stem-first procedure) is generally accepted as the optimal technique to attain an appropriate CA...  相似文献   
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Reproductive toxicities and endocrine disruptions caused by chemicals in adult males are still poorly understood. It is our objectives to understand further details of the initial adverse effects leading severe testicular toxicities of a pharmaceutical endocrine disruptor, diethylstilbestrol (DES). Downregulations of both testicular regulatory proteins, such as the steroidogenic acute regulatory protein (StAR) and the peripheral benzodiazepine receptor (PBR), which play important roles in the transport of cholesterol into the mitochondria, and cytochrome P450 mediating the cholesterol side chain cleavage reaction (P450scc), were observed in the rat orally administered DES (340 μg/kg/2 days) for 2 weeks. We found that after only 1 week treatment with DES, the blood and testicular testosterone (TS) levels were drastically decreased without abnormalities of the StAR and PBR; however, the protein and mRNA levels of P450scc were diminished. Decrease in the conversion rate of cholesterol to pregnenolone was delayed in the in vitro assay using the testicular mitochondrial fraction from the rat treated with DES for 1 week. When the precursors in TS biosynthesis containing the testis were identified and determined by liquid chromatography‐mass spectrometry analysis, decreased levels of all precursors except cholesterol were observed. In conclusion, suppressed cytochrome P450scc expression in adult male rat was identified as an initial target of DES in testicular steroidogenesis disorder leading reproductive toxicities. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1452–1459, 2014.  相似文献   
68.
The purpose of this study was to evaluate the clinical and radiographic treatment effects of percutaneous autologous concentrated bone marrow grafting in nonunion cases and to evaluate the effectiveness of this grafting procedure. We enrolled 17 cases those had atrophic changes due to continuous nonunion for over 9 months after injury and had undergone low-intensity pulsed ultrasound treatment for more than 3 months. The site of nonunion was the femur in 10 cases, the tibia in 5 cases, the humerus in 1 case, and the ulna in 1 case. They underwent percutaneous autologous concentrated bone marrow grafting and continued low-intensity pulsed ultrasound stimulation treatment after grafting. Patients were evaluated using the visual analogue scale for pain at immediately before the procedure, 3, 6, and 12 months after grafting. Plain radiographs of the affected site were taken and evaluated about the healing of the nonunion site at each clinical evaluation. As quantitative assessment, CT scans were undertaken before the procedure and 6 months after grafting. The visual analogue scale pain score was reduced consistently after grafting in all patients. About the healing at the nonunion site, 11 and 13 cases of bone union were observed at 6 and 12 months after grafting. The mean volume of callus formation based on CT images was 4,147 (262–27,392) mm3 total between grafting and 6 months. Percutaneous autologous concentrated bone marrow grafting is an effective procedure for the treatment of patients with nonunion.  相似文献   
69.
Obligate anaerobes exist as resident flora in various sites in humans, but they are also emphasized as endogenous causative microorganism of infections. We performed surveillance to understand the trend of drug susceptibility in obligate anaerobic bacteria in the Kinki area of Japan. In the experiment, we used 156 obligate anaerobe isolates collected from 13 institutions that participated in the Study of Bacterial Resistance Kinki Region of Japan. MALDI Biotyper was used to identify the collected strains, and among the 156 test strains, those that could be identified with an accuracy of Score Value 2.0 or more included 6 genera, 30 species, and 144 strains (Bacteroides spp. 77 strains, Parabacteroides sp. 2 strains, Prevotella spp. 29 strains, Fusobacterium spp. 14 strains, Porphyromonas spp. 2 strains, and Clostridioides difficile 20 strains), and they were assigned as subject strains for drug susceptibility testing. The drug susceptibility test was carried out by broth microdilution method using Kyokuto Opt Panel MP ANA (Kyokuto Pharmaceutical Industrial Co., Ltd., Tokyo, Japan) and judged according to CLSI criteria. As a result, Bacteroides and Parabacteroides species showed good sensitivities to tazobactam-piperacillin, imipenem, metronidazole and chloramphenicol, and low sensitivities to ampicillin, cefoperazone and vancomycin. Prevotella species showed good sensitivities to sulbactam-ampicillin, tazobactam-piperacillin, cefmetazole, imipenem, doripenem and metronidazole. Susceptibility rates to other drugs were slightly different depending on the bacterial species. Both Fusobacterium spp. and Porphyromonas spp. showed high sensitivities to many drugs. C. difficile was highly sensitive to vancomycin and metronidazole, having MIC90s of 0.5 μg/mL and ≤2 μg/mL, respectively.  相似文献   
70.
BACKGROUND/AIMS: The cells constituting a bioartificial liver are crucial for an effective liver support system. We compared global gene expression profiles in a radial flow bioreactor or a monolayer culture of three functional liver cell lines previously established from human hepatocellular carcinoma. METHODS: The expressions of 60,000 genes of the FLC-4, FLC-5, and FLC-7 cell lines were analyzed by the microarray technique with the Affymetrix GeneChip system. Global gene expression profiles were compared with two-way cluster analysis. Several liver function-related genes were compared between the bioreactor and culture conditions. RESULTS: Cluster analysis revealed that gene expression profiles of bioreactor-grown cells resembled those of the normal liver. Genes related to cellular structure were highly expressed in the bioreactor-grown cells, while genes involved in proliferation or carcinogenesis were suppressed. In the bioreactor-grown cells, some genes for liver functions were expressed at a level similar to that in normal liver, although none of the cell lines expressed the complete set of genes encoding ammonium metabolism or cytochrome P450 species. CONCLUSION: The high-density three-dimensional culture in the radial flow bioreactor prompted differentiation of the cells. These data may be useful for improving the cells by genetic or pharmacological reinforcement and for monitoring bioartificial livers.  相似文献   
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