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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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The accumulation of abnormal prion protein (PrPSc) produced by the structure conversion of PrP (PrPC) in the brain induces prion disease. Although the conversion process of the protein is still not fully elucidated, it has been known that the intramolecular chemical bridging in the most fragile pocket of PrP, known as the “hot spot,” stabilizes the structure of PrPC and inhibits the conversion process. Using our original structure-based drug discovery algorithm, we identified the low molecular weight compounds that predicted binding to the hot spot. NPR-130 and NPR-162 strongly bound to recombinant PrP in vitro, and fragment molecular orbital (FMO) analysis indicated that the high affinity of those candidates to the PrP is largely dependent on nonpolar interactions, such as van der Waals interactions. Those NPRs showed not only significant reduction of the PrPSc levels but also remarkable decrease of the number of aggresomes in persistently prion-infected cells. Intriguingly, treatment with those candidate compounds significantly prolonged the survival period of prion-infected mice and suppressed prion disease-specific pathological damage, such as vacuole degeneration, PrPSc accumulation, microgliosis, and astrogliosis in the brain, suggesting their possible clinical use. Our results indicate that in silico drug discovery using NUDE/DEGIMA may be widely useful to identify candidate compounds that effectively stabilize the protein.Electronic supplementary materialThe online version of this article (10.1007/s13311-020-00903-9) contains supplementary material, which is available to authorized users.  相似文献   
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Individuals infected with the novel coronavirus (Severe Acute Respiratory Syndrome Coronavirus 2 [SARS-CoV-2]) who develop coronavirus disease 2019 (COVID-19) experience many symptoms; however, cutaneous manifestations are relatively rare. The authors encountered three patients with COVID-19 who presented with erythema and suspected viral rash. In all cases, erythema appeared after the onset of the initial symptoms of COVID-19. Erythema was considered to be caused by COVID-19 and not a drug-induced eruption because, in all cases, erythema was relieved merely by external medicine and oral antihistamines, without discontinuing the original medication. The authors’ hospital accepted 69 COVID-19 patients between 22 February 2020 and 31 May 2020 and, of these, three (4.3%) exhibited eruptions, and all cases presented erythema. Except for seven patients who exhibited positive nasopharyngeal swab tests for SARS-CoV-2 RNA but no symptoms, three (4.8%) of the remaining 62 patients exhibited erythema. Although various types of eruptions have been reported in patients with COVID-19, erythema was the only type in our patients. Erythema in the three patients exhibited many similarities to that previously reported in COVID-19 patients, particularly in the manner it appeared and disappeared. For these reasons, these three cases were considered typical examples of erythema in patients with COVID-19. Considering previous studies and the three cases reported here, there is a high probability that SARS-CoV-2 can cause erythema.  相似文献   
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We report the successful endovascular repair of a rare case of aortic rupture caused by axillary intra-aortic balloon pump (IABP) insertion failure. A 38-year-old Jehovah's Witness female with situs inversus totalis was referred to our hospital for acute decompensated heart failure. We placed an axillary IABP for circulatory support. However, an exchange was required due to balloon malfunction (kinked driveline). Unfortunately, the exchange was complicated by an iatrogenic aortic rupture along with a large hematoma compressing the trachea. Emergent endovascular repair was performed successfully without any blood transfusion. Postoperative computed tomography showed a successfully repaired aorta and resolving hematoma.  相似文献   
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