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991.
992.
The gene for the DNA-repair enzyme O6-methylguanine-DNA methyltransferase (MGMT), which is closely related with cellular sensitivity to alkylating agents, is inactivated by promoter hypermethylation in several human cancers, including malignant lymphoma. Promoter hypermethylation of the MGMT gene is a favorable prognostic factor in diffuse large B-cell lymphoma (DLBCL). Although inactivation of the MGMT gene is closely related to p53 gene mutations in several cancers, the relationship between p53 gene mutation and MGMT inactivation in malignant lymphoma has not been thoroughly examined. We studied the correlation between MGMT hypermethylation and p53 mutation in DLBCL and their impacts on patient prognosis. In a retrospective cohort study, we used a methylation-specific polymerase chain reaction technique to analyze the methylation status of the promoter region of the MGMT gene in 116 DLBCL patients who received cyclophosphamide as part of multidrug combination chemotherapies. Denaturing high-performance liquid chromatography and direct sequencing were used to search for p53 gene mutations in exons 5 through 9 in 96 of the 116 samples. Disease-free survival and overall survival were estimated by the Kaplan-Meier method. Multivariate survival analyses were performed with the Cox proportional hazards model. Forty-five (38.8%) of 116 DLBCL patients showed MGMT promoter hypermethylation. The presence of MGMT hypermethylation was associated with better overall survival (P = .036). MGMT promoter hypermethylation was a prognostic factor that was independent of established prognostic factors, such as age, disease stage, serum lactic dehydrogenase level, and the number of extranodal disease sites (hazard ratio, 2.43; 95% confidence interval, 1.28-4.61; P = .007). p53 mutations were detected in 19 (19.8%) of 96 patients and were identified as a risk factor in the complete remission rate and overall survival (P = .0040, and P = .027, respectively). A correlation between MGMT hypermethylation and p53 mutation or p53 G:C-to-A:T mutation was not observed (P = .88, and P = .31, respectively). MGMT promoter hypermethylation and p53 mutation are useful prognostic markers in DLBCL. The impact of MGMT inactivation on p53 mutation in DLBCL is unclear.  相似文献   
993.
It is speculated that more than 400 bacterial species reside in the oral cavity. Some cause inflammation (e.g. periodontitis), understanding of which requires examination of innate immunity in the oral cavity. Oral mucosal cells such as epithelial cells are thought to act as a physical barrier against the invasion of pathogenic organisms, but they have an ability to produce inflammatory cytokines and express adhesion molecules. Oral epithelial cells are refractory to many bacterial components although they express Toll-like receptors/MyD88, and acquire responsiveness after priming with IFN-gamma. When the cells are stimulated with lipopolysaccharide (LPS) and neutrophil protease (PR3) after IFN-gamma priming, the cells produce bio-active IL-18, which is critical to Th1 and Th2 responses. PR3 itself is able to activate the cells through G protein-coupled protease-activated receptor-2 on the cell surface. These results suggest that innate immune responses of oral epithelial cells to bacterial components are regulated in the inflammatory process. In addition, saliva contains abundant bio-active CD14 from salivary glands in a soluble form, although LPS-binding protein was below detectable levels, suggesting that saliva CD14 is important for the maintenance of oral health.  相似文献   
994.
BACKGROUND & AIMS: Cholecystitis after metallic stent (MS) placement is an issue requiring attention. From our experience, cholecystitis seemed to occur mainly in patients with tumor involvement to the cystic duct orifice. The aim of the present study was to identify risk factors for cholecystitis in patients treated with covered or uncovered MS. METHODS: We analyzed 246 patients who received MS placement (covered MS in 171 and uncovered in 75) between August 1997 and May 2005 for the treatment of unresectable distal malignant biliary obstruction. Causative diseases were as follows: pancreatic cancer in 162, papillary cancer in 10, bile duct cancer in 41, and metastatic nodes in 33 patients. Tumor involvement to orifice of the cystic duct (OCD) was diagnosed based on cholangiography and intraductal ultrasonography. RESULTS: Cholecystitis after MS placement was found in 13 patients (5.3%). There was no significant difference in the incidence of cholecystitis between covered (5.8%) and uncovered (4.0%) MS. By univariate analysis, tumor involvement of the OCD, MS placed above the papilla, and stricture located at midportion were associated significantly with cholecystitis. By multivariate analysis, only tumor involvement of the OCD was a risk factor, with an odds ratio of 47.206 (95% confidence interval, 5.84-381.60). CONCLUSIONS: Cholecystitis after MS placement is associated with tumor involvement to the orifice of the cystic duct, regardless of the type of stent.  相似文献   
995.
The indication of allogeneic stem cell transplantation (allo-SCT) for Philadelphia chromosome-negative acute lymphocytic leukemia [Ph(?) ALL] from unrelated donors is not established. To assess its potency of unrelated patients in first complete-remission (CR1) transplanted from unrelated donors and the potential prognostic factors affecting the probability of survival, we retrospectively analyzed a total of 41 adult Ph(?) ALL patients in CR1 who underwent unrelated bone marrow transplantation at 6 transplantation centers of the Nagoya Blood and Marrow Transplantation Group between 1993 and 2006. The median age of the 41 patients was 28 years (range, 18–51 years). HLA was matched in 33 transplants, with mismatches in 8 (HLA-A allele mismatch:1, HLA-DR serological mismatch: 2, HLA-DRB1 mismatch: 5). Leukemia-free survival (LFS) at 3 and 6 years from allo-SCT was 60.3 and 47.7%, respectively. LFS at 5 years was 62.1% for those transplanted from HLA-matched donors. LFS was significantly lower with HLA-mismatched donors due to higher transplantation-related mortality. Relapse was observed in 3 patients. Our study suggested that unrelated allo-SCT could improve LFS of patients with a potential graft-versus-leukemia effect. Unrelated allo-SCT for Ph(?) ALL patients in CR1 could be more beneficial by reducing TRM, such as selecting a HLA-matched donor.  相似文献   
996.
Despite the positive impact of percutaneous coronary intervention (PCI) on reducing mortality, a small percentage of patients experience poor myocardial reperfusion following PCI. However, factors associated with no-reflow remain unclear. We investigated clinical factors associated with no-reflow following PCI for coronary artery disease (CAD). We retrospectively analyzed 1622 consecutive CAD patients who underwent PCI over a 5-year period at our institution. Patients were divided into two groups according to the presence (n = 31) or absence (n = 1591) of no-reflow, defined as Thrombolysis in Myocardial Infarction flow grade <3 after PCI. No significant differences in patient characteristics or PCI strategy were seen between the no-reflow and normal flow groups. The incidence of no-reflow was significantly lower in the left circumflex artery (LCx) than in the left anterior descending artery (LAD) (P = 0.0015), with no differences in characteristics or PCI strategy between these two target vessels. Multivariate analysis revealed that involvement of the LCx was an independent protective factor against no-reflow (odds ratio 0.14, 95 % confidence interval 0.02–0.98, P = 0.044). In conclusion, LCx as the target vessel was protective against no-reflow compared with LAD following PCI for CAD. Our results suggest that embolic protection devices may be unnecessary in CAD patients with involvement of LCx.  相似文献   
997.
Immune checkpoint inhibitor (ICI)-induced myocarditis is a potentially life-threatening adverse event. We herein report a rare case of sick sinus syndrome (SSS) co-occurring with ICI-associated myocarditis. A 71-year-old woman with lung cancer undergoing pembrolizumab monotherapy was admitted owing to a fever, worsening kidney function, and sinus bradycardia. She was diagnosed with multi-organ immune-related adverse events, including myocarditis. Pulse steroid therapy was initiated immediately under the support of a temporary pacemaker, which resulted in the resolution of SSS in a few days. Biopsy specimens of the endomyocardium showed active myocarditis. Thus, we should be aware that SSS can co-occur with ICI-induced myocarditis.  相似文献   
998.
A 53-year-old woman with severe coronavirus disease 2019 (COVID-19) pneumonia was admitted and treated with intravenous unfractionated heparin for thromboprophylaxis under general anesthesia with mechanical ventilation. She developed right hemiparesis after hospitalization due to a large hemorrhagic infarction. Her platelet count decreased from 243,000 /μL at administration to 121,000 /μL. Anti-platelet factor 4-heparin antibody testing was positive according to a latex immunoturbidimetric assay. She was therefore diagnosed with heparin-induced thrombocytopenia. We immediately stopped the heparin and started argatroban; the platelet count recovered, and thrombosis did not relapse. Physicians should consider heparin-induced thrombocytopenia as a cause of ischemic stroke in patients with COVID-19 infection.  相似文献   
999.
Surveillance of bat betacoronaviruses is crucial for understanding their spillover potential. We isolated bat sarbecoviruses from Rhinolophus cornutus bats in multiple locations in Japan. These viruses grew efficiently in cells expressing R. cornutus angiotensin converting enzyme-2, but not in cells expressing human angiotensin converting enzyme-2, suggesting a narrow host range.  相似文献   
1000.
Fish and omega-3 fatty acid consumption is known to be beneficial for cardiometabolic health. However, the related evidence for individuals with a relatively higher intake of fish or omega-3 unsaturated fatty acids, e.g., Japanese individuals, is scarce. Therefore, this study aimed to examine the association of fish and omega-3 fatty acid intakes with the carotid intima-media thickness (C-IMT) in the Japanese population. In total, 1803 Japanese men and women aged 30–84 years without a history of myocardial infarction or angina pectoris were included in the study. The fish and omega-3 fatty acid intakes were estimated using food frequency questionnaires. The C-IMT was measured using ultrasound imaging, and the participants were classified into three groups: normal, moderate (1.1 to 1.4 mm of maximum C-IMT), and severely increased C-IMT (≥1.5 mm). Multinomial logistic regression models were used to calculate the odds ratio (OR) and 95% confidence intervals (95% CI) of the presence of moderately and severely increased C-IMT. The omega-3 fatty acid intake was shown to be associated with lower odds of severely increased C-IMT. The multivariable-adjusted OR (95%CI) was 0.55 (0.31–0.97; p for trend = 0.04). We also found a borderline significant negative association between fish intake and the presence of severely increased C-IMT. In conclusion, omega-3 fatty acid intake might protect against the development of atherosclerosis in the Japanese population.  相似文献   
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