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81.
Probiotics inhibit nuclear factor-kappaB and induce heat shock proteins in colonic epithelial cells through proteasome inhibition 总被引:6,自引:0,他引:6
Petrof EO Kojima K Ropeleski MJ Musch MW Tao Y De Simone C Chang EB 《Gastroenterology》2004,127(5):1474-1487
BACKGROUND AND AIMS: The extent and severity of mucosal injury in inflammatory bowel diseases are determined by the disequilibrium between 2 opposing processes: reparative and cytoprotective mechanisms vs. inflammation-induced injury. Probiotics may provide clinical benefit by ameliorating colitis; however, their mechanisms of action remain largely unknown. Our objective was to investigate microbial-epithelial interactions that could explain the beneficial therapeutic effects of probiotics. METHODS: The effect of VSL#3-conditioned media on the nuclear factor-kappaB pathway in young adult mouse colonic epithelial cells was assessed by using monocyte chemoattractant protein-1 enzyme-linked immunosorbent assays; IkappaBalpha, IkappaBbeta, and p105 immunoblot analysis; and nuclear factor-kappaB luciferase reporter gene and proteasome assays. Effects on heat shock proteins were determined by electrophoretic mobility shift assay and immunoblot for heat shock proteins 25 and 72 in young adult mouse colonic cells. Cytoprotection against oxidant injury was determined by chromium 51 release and filamentous and globular actin assays. RESULTS: VSL#3 produces soluble factors that inhibit the chymotrypsin-like activity of the proteasome in gut epithelial cells. Proteasome inhibition is an early event that begins almost immediately after exposure of the epithelial cells to the probiotic-conditioned media. In addition, these bacteria inhibit the proinflammatory nuclear factor-kappaB pathway through a mechanism different from the type III secretory mechanisms described for other nonpathogenic enteric flora. They also induce the expression of cytoprotective heat shock proteins in intestinal epithelial cells. CONCLUSIONS: The resulting inhibition of nuclear factor-kappaB and increased expression of heat shock proteins may account for the anti-inflammatory and cytoprotective effects reported for probiotics and may be a novel mechanism of microbial-epithelial interaction. These effects seem to be mediated through the common unifying mechanism of proteasome inhibition. 相似文献
82.
83.
Heat shock protein 70 (Hsp70) has been found to play key roles in tumor immunity due its chaperone function of binding antigenic peptides. Here we report it can also stimulate NK cells in vivo, which is another role in Hsp70s' anti-tumor response. Injecting Hsp70 into mice increased splenic NK cell populations, which may be reason for anti-tumor effect of Hsp70. The Hsp70 14-mer peptide (aa450–463, TRD) was identified as the critical epitope for this stimulatory activity. It was the murine Hsp70 14-mer peptide TRD instead of the corresponding human Hsp70 14-mer peptide TKD that functioned in the mouse experimental model. 相似文献
84.
Heita Kitajima Yuichiro Oba Takahisa Ohira Tomohiro Asaoka Yoshihiro Atsumi Takahiro Nakajima Takayuki Okura 《Journal of infection and chemotherapy》2021,27(5):766-769
To date, only 26 cases of Mycobacterium wolinskyi infections have been reported in humans. We herein report a first case of prosthetic valve endocarditis due to this organism after cardiovascular surgery. An 82-year-old man presented with repeat episodes of syncope and fever after aortic valve replacement, mitral valve replacement, left atrial appendage closure, and pulmonary vein isolation. Blood cultures maintained in aerobic bottles were repeatedly positive after 90–100 hours, and Gallium scan revealed abnormal accumulations in the sternum and left testis. While colonies formed by culturing the fluid of the parasternal area and blood cultures revealed gram-positive rods, we could not analyze the colony using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF). M. wolinskyi was finally identified on 16S rRNA, hsp65, and rpoB gene sequencing. We treated the patient with multiple antimycobacterial drugs, i.e., amikacin, imipenem, and clarithromycin for 6 weeks, which was changed to oral ciprofloxacin and minocycline for 12 months. This case highlights the need to consider rapidly growing mycobacteria, including M. wolinskyi, if chronic fever persists from weeks to months after surgery, the blood culture is positive, and the organism is not identified. In addition, sequencing the 16S rRNA, hsp65, and rpoB genes is essential for diagnosis. 相似文献
85.
3第三阶段:药学服务,创新驱动国内外药学界普遍认为,未来医院药学应以患者健康为目标、“药学服务”为重点的药学专业服务工作。20世纪90年代中期,药学服务的理念传入我国,上海长海医院药学部胡晋红教授提出的“全程化药学服务”(integrated pharmaceutical care)概念获得普遍认同。在这个框架内,药师与患者、医护人员及其他专业人员进行合作,药师增加对药物使用监控的职能,以及为达到改善患者健康和生活质量这个特定目标而提供服务。药学服务包括用药前的宣传教育,用药过程中的顾问、监测及用药后的监测与评价[5]。20世纪90年代至今,医院药学处于药学服务阶段,以现代药学及临床药学为支柱,支持这一工作的基础学科为药物治疗学、临床药学及计算机网络化管理技术[1]。 相似文献
86.
Shannon J Ernst P Yamauchi Y Olivenstein R Lemiere C Foley S Cicora L Ludwig M Hamid Q Martin JG 《Chest》2008,133(2):420-426
BACKGROUND: Some studies of severe asthma suggest that persistence or alteration in the pattern of inflammation may be associated with the severity of the disease. Whether there are differences in the expression of the principal cytokines and chemokines relevant to eosinophilic and neutrophilic inflammation in the airway tissues of severe compared to moderate asthmatics has not been determined. The aim of this study was to compare the patterns of expression of representative T-helper (Th) type 1 (interferon [IFN]-gamma) and Th-2 cytokines (interleukin [IL]-4, IL-5) and the neutrophil- and eosinophil-associated chemokines (IL-8 and eotaxin) in the airway tissues of patients with severe and moderate asthma. METHODS: Subjects with severe asthma (n = 24) and a comparison moderate asthma group (n = 26) were assessed using spirometry, induced sputum, exhaled nitric oxide, and bronchial biopsy. The expression of proteins of interest in the epithelium and subepithelium of the airway wall was examined by immunocytochemistry. RESULTS: Subjects with severe asthma were more symptomatic, had a lower FEV(1), and had more sputum neutrophilia (p = 0.007) and eosinophilia (p = 0.001). Exhaled nitric oxide was similar between groups. IL-8 and IFN-gamma expression were increased and IL-4 expression was decreased in severe asthma compared to moderate disease (p < 0.001 for each comparison). Eotaxin and IL-5 expression did not differ between the groups. CONCLUSION: Patients with severe asthma have increases in neutrophils and eosinophils in the sputum, and differ in airway cytokine/chemokine expression from moderate asthmatics. Excess neutrophilia may be explained by increased expression of IL-8, but differences in eosinophilia do not appear to be associated with IL-5 and eotaxin expression. 相似文献
87.
An increasing proportion of critically ill patients are elderly (ie, >or= 65 years of age). This poses complex challenges and choices for the management of elderly patients. Outcome following admission to the ICU has been traditionally concerned with mortality. Beyond mortality, outcomes such as functional status and health-related quality of life (HRQOL) have assumed greater importance. This article reviews the literature, published in English from 1990 to December 2003, pertaining to HRQOL and functional status outcomes of elderly patients. Functional status and HRQOL of elderly survivors of ICUs has been underinvestigated. There is no agreement as to the optimal instrument choice, and differences between studies preclude meaningful comparison or pooling of results. 相似文献
88.
艾灸足三里和梁门穴诱导热休克蛋白70抗大鼠胃黏膜氧化损伤作用 总被引:15,自引:0,他引:15
目的:观察艾灸足三里和梁门穴对应激性溃疡大鼠胃黏膜热休克蛋白70(HSP70)表达的影响,探讨艾灸足阳明经穴抗胃黏膜氧化损伤的作用机制.方法:将SD大鼠60只完全随机平均分为空白组、模型组、艾灸足三里等穴组和艾灸非穴对照点组,采用水浸-束缚应激法制备应激性溃疡模型.按Guth法计算胃黏膜损伤指数(UI),用激光多普勒血流仪测定胃黏膜血流量(GMBF),用免疫组织化学法和硫代巴比妥酸染色法对处理后大鼠检测其胃黏膜HSP70的表达和丙二醛(MDA)的含量.结果:与模型组和艾灸非穴组比较,艾灸足三里等穴可使应激性溃疡大鼠胃黏膜损伤指数明显下降(14.100±5.425vs26.800±9.807,26.200±7.729,P<0.01),HSP70表达上调(0.133±0.035vs0.077±0.057,0.059±0.038,P<0.01)、血流量增高(279.827±172.862mL/minvs139.489±33.133,141.512±58.450mL/min,P<0.05)、MDA含量减少(2.586±0.252μmol/Lvs3.906±0.768,3.464±1.502μmol/L,P<0.05).结论:艾灸足三里和梁门穴能诱导胃黏膜HSP70高表达并降低MDA含量,以达到其抗氧化损伤作用,并有相对的穴位特异性. 相似文献
89.
Correlation between clinicopathology and expression of heat shock protein 70 and glucose-regulated protein 94 in human colonic adenocarcinoma 总被引:14,自引:0,他引:14
AIM: To investigate the correlation between clinicopathology and expression of heat shock protein 70 (HSP70) and glucose-regulated protein 94 (grp94) in human colonic carcinoma. METHODS: The expression of HSP70 and grp94 was studied in 80 human colonic cancers with or without metastasis as well as in their adjacent mucous membrane by way of immunohistochemistry and pathology photograph analysis. RESULTS: The expression of HSP70 and grp94 was significantly higher in cancer than that in adjacent mucous membrane (92.5%, 85.0% vs 56.3%, 42.5%, P<0.01). HSP70 and grp94 expressed higher in moderately- and poorly-differentiated colonic cancers than that in their adjacent tissues (93.7%, 87.5%; 100%, 90% vs56.3%, 42.5%;P<0.01). Dukes C and D stages of colonic cancers showed higher positive rates than Dukes A and B stage groups (97.1%, 91.2%; 100%, 90.9%; vs 80%, 70%; 78.6%, 71.4%; P<0.05). There were definite differences in HSP70 and grp94 expression between metastasis groups and non-metastasis groups (100% vs 75%, 100% CONCLUSION: The HSP70 and grp94 expression rates in colonic cancer groups are significantly higher than that in their adjacent mucous membrane. The HSP70 and grp94 expression in poorly-differentiated colonic cancers with metastasis is significantly higher than well-differentiated cancers without metastasis. The overexpression of HSP70 and grp94 can be used as diagnostic or prognostic markers for colonic cancer. 相似文献
90.
Cystic fibrosis patients have poor sleep quality despite normal sleep latency and efficiency 总被引:2,自引:0,他引:2
STUDY OBJECTIVES: Cystic fibrosis (CF) patients may be predisposed to poor sleep quality due to upper and lower airway abnormalities and impaired gas exchange. Previous sleep investigations of CF patients using single-night polysomnography have reported conflicting results. We hypothesized that sampling sleep for a prolonged period in a patient's normal environment may give a more representative assessment of sleep quality than a single-night polysomnogram, and that impaired sleep quality would correlate with pulmonary disease severity and self-assessed sleep quality. DESIGN: Using wrist actigraphy, we measured sleep quality in clinically stable CF patients and age-matched control subjects. In addition, each CF patient and control subject completed the following three questionnaires: the Epworth sleepiness scale; the Pittsburgh sleep quality index (PSQI); and the Medical Outcomes Study 36-item short form. RESULTS: Twenty CF patients and control subjects were enrolled in the study, and were well-matched for age, sex, and body mass index. The mean (+/- SD) FEV(1) for CF patients was 61.0 +/- 20.1% predicted. CF patients and control subjects had similar sleep duration, sleep latency, and sleep efficiency. However, CF patients had higher PSQI scores (6.45 vs 4.55, respectively; p = .04), a higher fragmentation index (FI) [31.72 vs 18.02, respectively; p < 0.001], and less immobile time (88.87 vs 91.89, respectively; p = 0.02). There was a significant correlation of FI with FEV(1) and PSQI scores. CONCLUSIONS: Stable CF patients have disrupted sleep, and sleep disruption may in part be related to the severity of pulmonary disease. In addition, the PSQI may be useful in detecting CF patients with poor sleep quality. 相似文献