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Hepatocyte growth factor activator inhibitor‐1 (HAI‐1), encoded by the SPINT1 gene, is a membrane‐bound protease inhibitor expressed on the surface of epithelial cells. Hepatocyte growth factor activator inhibitor‐1 regulates type II transmembrane serine proteases that activate protease‐activated receptor‐2 (PAR‐2). We previously reported that deletion of Spint1 in ApcMin/+ mice resulted in accelerated formation of intestinal tumors, possibly through enhanced nuclear factor‐κB signaling. In this study, we examined the role of PAR‐2 in accelerating tumor formation in the ApcMin/+ model in the presence or absence of Spint1. We observed that knockout of the F2rl1 gene, encoding PAR‐2, not only eliminated the enhanced formation of intestinal tumors caused by Spint1 deletion, but also reduced tumor formation in the presence of Spint1. Exacerbation of anemia and weight loss associated with HAI‐1 deficiency was also normalized by compound deficiency of PAR‐2. Mechanistically, signaling triggered by deregulated protease activities increased nuclear translocation of RelA/p65, vascular endothelial growth factor expression, and vascular density in ApcMin/+‐induced intestinal tumors. These results suggest that serine proteases promote intestinal carcinogenesis through activation of PAR‐2, and that HAI‐1 plays a critical tumor suppressor role as an inhibitor of matriptase, kallikreins, and other PAR‐2 activating proteases.  相似文献   
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Journal of Neuro-Oncology - This study aimed to investigate the preoperative predictive factors affecting return to work in patients with gliomas in the left cerebral hemisphere undergoing awake...  相似文献   
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A significant population of neurons in the vestibular nuclei projects to the cerebellum as mossy fibers (MFs) which are involved in the control and adaptation of posture, eye-head movements, and autonomic function. However, little is known about their axonal projection patterns. We studied the morphology of single axons of medial vestibular nucleus (MVN) neurons as well as those originating from primary afferents, by labeling with biotinylated dextran amine (BDA). MVN axons (n = 35) were classified into three types based on their major predominant termination patterns. The Cbm-type terminated only in the cerebellum (15 axons), whereas others terminated in the cerebellum and contralateral vestibular nuclei (cVN/Cbm-type, 13 axons), or in the cerebellum and ipsilateral vestibular nuclei (iVN/Cbm-type, 7 axons). Cbm- and cVN/Cbm-types mostly projected to the nodulus and uvula without any clear relationship with longitudinal stripes in these lobules. They were often bilateral, and sometimes sent branches to the flocculus and to other vermal lobules. Also, the iVN/Cbm-type projected mainly to the ipsilateral nodulus. Neurons of these types of axons showed different distribution within the MVN. The number of MF terminals of some vestibulocerebellar axons, iVN/Cbm-type axons in particular, and primary afferent axons were much smaller than observed in previously studied MF axons originating from major precerebellar nuclei and the spinal cord. The results demonstrated that a heterogeneous population of MVN neurons provided divergent MF inputs to the cerebellum. The cVN/Cbm- and iVN/Cbm-types indicate that some excitatory neuronal circuits within the vestibular nuclei supply their collaterals to the vestibulocerebellum as MFs.  相似文献   
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Our aim was to find out whether the quality of bone around the inferior alveolar nerve is correlated with neurosensory disturbance to the nerve after sagittal split ramus osteotomy (SSRO) in patients with mandibular prognathism. Computed tomograms (CT) were taken of 35 patients with mandibular prognathism and 35 without. To assess the density of bone around the inferior alveolar nerve, the width of the buccal cortical bone in the mandibular second molar regions was measured on CT. The Hounsfield units (HU) in the same regions were also measured. The number of HU in the mandible around the second molar regions was significantly higher (p < 0.01) in those with neurosensory disturbance (p < 0.01). The quality of bone measured by HU is associated with an increased risk of neurosensory disturbance, but the width of buccal bone is not.  相似文献   
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Immunochemical detection of CD14 on human gingival fibroblasts in vitro   总被引:2,自引:0,他引:2  
The activation of monocytes and macrophages induced by lipopolysaccharide has been shown to contribute to the binding of lipopolysaccharide and lipopolysaccharide-binding protein complex to the cell surface CD14 molecule. To clarify the mechanism of the lipopolysaccharide-induced modulation of the function of gingival fibroblasts, we investigated the effect of anti-CD14 on interleukin 6 (IL-6) production on human gingival fibroblasts in vitro. Immunochemical staining revealed weak positivity for CD14 on fibroblasts from healthy gingiva, while strong positivity for CD14 was found on fibroblasts from inflamed gingiva. Western blot profiles of the fibroblasts and monocytes showed a CD14-positive reaction at 55 kDa. Fluorescein isothiocyanate-conjugated Escherichia coli lipopolysaccharide bound to fibroblasts more strongly in the presence of 10% fetal bovine serum than without serum. This binding, as well as IL-6 production, was blocked by anti-CD14 monoclonal antibody. The results showed that CD14 was present on human gingival fibroblasts, which suggests that lipopolysaccharide modulation of gingival fibroblast function depends on CD14.  相似文献   
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