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991.
ObjectiveThe aim of this retrospective study is to evaluate the usefulness of upper gastrointestinal endoscopy and the Valsamouth? by an otolaryngologist in patients with hypopharyngeal cancer to assess the risk.MethodsThe study group comprised 41 patients with untreated hypopharyngeal cancer that was precisely diagnosed by an otolaryngologist using upper gastrointestinal endoscopy and the Valsamouth? at our hospital from January 2016 to December 2017. With upper gastrointestinal endoscopy and the Valsamouth?, the oral cavity, oropharynx, larynx, hypopharynx, and esophagus were observed in this order. Narrow-band imaging, and subsequently, white-light observation were performed. At the hypopharynx, vocalization, and subsequently, the Valsalva maneuver were performed. After observing the esophagus, Lugol chromoendoscopy of the esophagus was performed.ResultsThe mean age of the 38 men and 3 women included in the study was 69.7 ± 10.0 years (range, 51–94 years). As for the T category of hypopharyngeal cancer, T1 cancer was observed in 9 patients, T2 cancer in 14, T3 cancer in 11, and T4 cancer in 7. With vocalization, the grade of visualization in the hypopharynx was 1 in 30 patients (73.2%), 2 in 11 patients (26.8%), and 3 or more in 0 patients (0.0%). With the Valsalva maneuver, the grade of visualization in the hypopharynx was 1 in 1 patient (2.4%), 2 in 15 patients (36.6%), 3 in 8 patients (19.5%), 4 in 11 patients (26.8%), and 5 in 6 patients (14.6%). The grade of visualization in the hypopharynx on average was 1.27 after vocalization and 3.15 after the Valsalva maneuver (p < 0.001). With vocalization, the percentage of patients in whom the entire image of hypopharyngeal cancer could be observed was 0.0% for grade 1 and 18.2% for grade 2. With the Valsalva maneuver, the percentage of patients in whom the entire image of hypopharyngeal cancer could be observed was 0.0% for grade 1, 40.0% for grade 2, 50.0% for grade 3, 86.1% for grade 4, and 100% for grade 5. Synchronous esophageal cancers were detected in 17.1% (7/41) of the patients. The grade of Lugol-voiding lesions was A in 5.6%, B in 52.8%, and C in 41.7%.ConclusionThe examination with upper gastrointestinal endoscopy and the Valsamouth? by an otolaryngologist is feasible in patients with hypopharyngeal cancer. This procedure can detect synchronous esophageal cancer, allowing the risk of metachronous cancer in the head and neck or the esophagus to be recognized after the treatment.  相似文献   
992.
T cells of the small intestine, including Th17 cells, are critically involved in host protection from microbial infection, and also contribute to the pathogenesis of small bowel inflammatory disorders. Accumulating evidence suggests that mesenteric lymph nodes (MLNs) play important roles in gut‐tropic T‐cell generation, although it is still unclear if MLNs are involved in the pathogenesis of small intestine inflammation. To address this issue, we analyzed the roles of both MLNs and Peyer's patches (PPs) by evaluating MLN‐ or PP‐deficient mice in an experimental model of small intestine inflammation, induced by CD3‐specific mAb injection. Interestingly, MLNs, but not PPs, were essential for the pathogenesis of intestinal inflammation, in particular the accumulation and infiltration of CD4+ T‐cell populations, including Th17 cells, from the blood. In addition, CD4+ T‐cell accumulation was dependent on the function of the α4β7 integrin. Furthermore, MLN removal led to a significantly reduced number of peripheral α4β7+ CD4+ effector memory T cells under normal conditions, suggesting that MLNs may play a role in maintaining the number of gut‐tropic CD4+ effector memory T cells circulating in the blood. Taken together, the present study highlights the important role of MLNs in contributing to the pathogenesis of small intestine inflammation.  相似文献   
993.
994.
E-cadherin and catenins play key roles in cell adhesion and motility. Little is known about the changes in expression of these molecules in the progression of ovarian carcinomas. In the present study, the immunohistochemical expression of E-cadherin and α-, β-, and γ-catenins was examined in 77 cases of ovarian carcinoma. In addition, the expression of these molecules was evaluated in 26 matched pairs of primary and metastatic lesions of advanced ovarian carcinomas. Of the 77 primary lesions, positive staining for E-cadherin and α-, β-, and γ-catenin was observed in 75 (97%), 63 (82%), 71 (92%) and 57 (74%) cases, respectively. Positivity for E-cadherin and α-, β-, and γ-catenin was significantly decreased in stage III and IV tumors compared with stage I and II tumors, suggesting that expression of the cadherin-catenin complex is reduced with the advancing stages of a tumor. Interestingly, expression of E-cadherin and α-, β-, and γ-catenin in the lesions of peritoneal dissemination was significantly increased compared with the primary lesions. These findings suggest that expression of the cadherin-catenin complex changes markedly and that reexpression may occur during the peritoneal dissemination of ovarian carcinoma cells.  相似文献   
995.
C57BL/6 mice were immunized intradermally with various doses of purified pCEP4 plasmid DNA containing full-length MUC1 cDNA (22 tandem repeats). Mice immunized with MUC1 DNA three times at weekly intervals had serum antibodies to a synthetic peptide corresponding to the tandem repeats of MUC1. The antibody titer correlated with the plasmid DNA dose. After the third immunization mice were injected intravenously with 5×105 B16-F10 melanoma cells that had been stably transfected with MUC1 cDNA (F10-MUC1-C8 clone cells). The number of lung metastatic nodules three weeks after inoculation of F10-MUC1-C8 cells was significantly lower in mice immunized with MUC1 plasmid DNA than in mice immunized with the vector DNA alone. Thus, the suppression of lung metastasis was antigen-specific. In vivo depletion of lymphocyte subpopulations by specific antibodies revealed that natural killer cells are the major effector cells responsible for the suppression of lung metastasis. CD4+ cells and CD8+ cells apparently played some roles too. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
996.
The effects of aniracetam, a cognition enhancer, on extracellular levels of glutamate (Glu), γ-aminobutyric acid (GABA) and nitric oxide metabolites (NOx) were examined in the prefrontal cortex (PFC) and the basolateral amygdala (AMG) in stroke-prone spontaneously hypertensive rats (SHRSP) using in vivo microdialysis. Basal release of Glu, was lower in the AMG of SHRSP than in normotensive Wistar Kyoto rats, whereas no difference in GABA and NOx was noted. Aniracetam (100 mg/kg, p.o.) significantly increased the area under the curve of Glu levels in the PFC, but not in the AMG, of SHRSP. Aniracetam failed to exert any remarkable effects on GABA or NOx levels in either brain region. Our findings suggest that aniracetam enhances cortical glutamatergic release, which may be the mechanism involved in the ameliorating effects of aniracetam on various neuronal dysfunctions.  相似文献   
997.
A significant increase in the CD38(+) population among T lymphocytes has been observed in human immunodeficiency virus type 1 (HIV-1)-infected carriers. We previously reported a higher replication rate of T-tropic HIV-1 in the CD4(+)CD38(+)CD62L(+) than CD38(-) subset under conditions of mitogen stimulation after infection. Here, we revealed a similarly high susceptibility in the CD38(+) subset on culture with conditioned medium containing Th2 cytokine, interleukin (IL)-4 that was produced endogenously from this subset on stimulation with mitogen or anti-CD3 antibody for 3 days. The contribution of IL-4 to the upregulated production of virus in the CD38(+) subset was confirmed by culture of this subset with recombinant human IL-4. In contrast, the rate of replication in the CD38(-) subset was not augmented in the conditioned medium from either subset or with IL-4. However, there were no differences in the surface expression of IL-4 receptor or HIV-1 receptors CD4 and CXCR4 between the two subsets. Thus, the CD4(+)CD38(+)CD62L(+) subset comprises a specific cell population secreting endogenous Th2 cytokine that contributes to the efficient production of T-tropic HIV-1 through upregulation at a certain stage of the viral life cycle, probably after the adsorption step.  相似文献   
998.
Mammalian brain memory is hypothesized to be established through two phases; short-term plasticity, as exemplified by long-term potentiation (LTP) where pre-existing synapses change transmission efficiency, and long-lasting plasticity where new synapses are formed. This hypothesis, however, has not been verified experimentally. Using cultured hippocampal slices, we show that the repeated induction of late-phase LTP by brief applications of forskolin (FK) led to a slowly-developing long-lasting synaptogenesis, as judged from electrophysiological, cytological and ultrastructural indices. These indices include (1) field postsynaptic potential standardized by field action potential, which should represent the number of synapses per neuron; (2) the amounts of synaptic marker proteins; (3) the number of synaptophysin-immunopositive puncta; (4) the number of dendritic spines per length; (5) the density of synaptic ultrastructures; (6) ultrastructures similar to synapse perforation. Increment in these indices occurred approximately 10 days after FK-application and outlasted the following weeks. The increment depended on the times and intervals of FK-application. A biologically inert FK analogue failed to produce the similar effect. An inhibitor for cyclic AMP-dependent protein kinase (PKA) blocked the synaptogenesis. The cultured brain slice repeatedly exposed to FK should serve as a good model system for the analysis of persistent synaptogenesis possibly related to long-term memory in mammalian CNS.  相似文献   
999.
1000.
The transendothelial migration of neutrophils is a critical step in acute inflammation, which we previously showed to be regulated by endothelial myosin light chain (MLC) kinase. Recent studies suggest that Rho and Rho kinase are also key mediators of MLC phosphorylation, but their roles in neutrophil migration have not been investigated. In the present study, a transwell chamber migration assay system incorporating endothelial monolayer was used to examine the numbers of migrating neutrophils, endothelial F-actin and myosin II rearrangement, and endothelial MLC phosphorylation at selected times during the neutrophil migration in vitro. The results showed that pretreating endothelial cells with C3 (Rho inhibitor) or Y-27632 (Rho kinase inhibitor) significantly diminished neutrophil migration, actin polymerization, myosin II filament formation, and MLC phosphorylation normally associated with the migration. These data suggest that endothelial Rho and Rho kinase regulate transendothelial neutrophil migration by modulating the cytoskeletal events that mediate such migration.  相似文献   
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