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91.
Although the medical management of fistulizing Crohn's disease is improving, a subset of patients does not respond to maximal medical therapy and is referred for surgical consultation. We report a case of Crohn's colitis with an ingested foreign body resulting in a cologastric fistula. The patient underwent segmental colectomy and takedown of the cologastric fistula. At the time of laparotomy, the foreign body was found in the fistulous colonic segment. The presence of an ingested foreign body likely contributed to a rare fistula that was refractory to medical management.  相似文献   
92.
Osteolytic lesions are rapidly progressive during the terminal stages of myeloma, and the bone pain or bone fracture that occurs at these lesions decreases the patients’ quality of life to a notable degree. In relation to the etiology of this bone destruction, it has been reported recently that MIP-1α, produced in large amounts in myeloma patients, acts indirectly on osteoclastic precursor cells, and activates osteoclasts by way of bone-marrow stromal cells or osteoblasts, although the details of this process remain obscure. In the present study, our group investigated the mechanism by which RANKL expression is induced by MIP-1α and the effects of MIP-1α on the activation of osteoclasts. RANKL mRNA and RANKL protein expressions increased in both ST2 cells and MC3T3–E1 cells in a MIP-1α concentration-dependent manner. RANKL mRNA expression began to increase at 1 h after the addition of MIP-1α; the increase became remarkable at 2 h, and continuous expression was observed subsequently. Both ST2 and MC3T3-E1 cells showed similar levels of increased RANKL protein expression at 1, 2, and 3 days after the addition of MIP-1α. After the addition of MIP-1α, the amount of phosphorylated ERK1/2 and Akt protein expressions showed an increase, as compared to the corresponding amount in the control group. On the other hand, the amount of phosphorylated p38MAPK protein expression showed a decrease from the amount in the control group after the addition of MIP-1α. U0126 (a MEK1/2 inhibitor) or LY294002 (a PI3K inhibitor) was added to ST2 and MC3T3-E1 cells, and was found to inhibit RANKL mRNA and RANKL protein expression in these cells. When SB203580, a p38MAPK inhibitor, was added, RANKL mRNA and RANKL protein expression were increased in these cells. MIP-1α was found to promote osteoclastic differentiation of C7 cells, an osteoclastic precursor cell line, in a MIP-1α concentration-dependent manner. MIP-1α promoted differentiation into osteoclasts more extensively in C7 cells incubated together with ST2 and MC3T3-E1 cells than in C7 cells incubated alone. These results suggested that MIP-1α directly acts on the osteoclastic precursor cells and induces osteoclastic differentiation. This substance also indirectly induces osteoclastic differentiation through the promotion of RANKL expression in bone-marrow stromal cells and osteoblasts. The findings of this investigation suggested that activation of the MEK/ERK and the PI3K/Akt pathways and inhibition of p38MAPK pathway were involved in RANKL expression induced by MIP-1α in bone-marrow stromal cells and osteoblasts. This finding may be useful in the development of an osteoclastic inhibitor that targets intracellular signaling factors.  相似文献   
93.
目的:观察L-硝基精氨酸(L—NA)对局灶性脑缺血损伤后炎症因子和神经细胞凋亡的影响。探讨L—NA保护脑缺血损伤组织的作用机制。方法:健康雄性SD大鼠,体重250—280g,随机分为3组(n=10):假手术组(SH组)、缺血组(IS组)、L—NA治疗组(L—NA组)。IS、L—NA组采用线栓法制备大鼠局灶性脑缺血损伤模型。L-NA组每次腹腔注射L—NA20mg/kg,每日2次,连续3d。IS组给予等量的生理盐水。将大鼠断头取脑,采用免疫组化法检测脑组织中TNF—α表达变化,放免法检测IL-1β水平变化,流式细胞仪测定脑组织神经元凋亡率、Bcl-2蛋白、Bax蛋白表达及Bcl-2蛋白与Bax蛋白比值(Bcl-2/BaX)。结果:与SH组比较,IS组脑缺血灶范围内TNF-α表达明显增强,IL-1β水平显著升高,神经凋亡率及Bax蛋白表达升高,Bcl-2/BaX降低;与IS组比较,L—NA组脑缺血灶范围内TNF-α表达及IL-1β水平显著降低,神经凋亡率降低,Bcl-2蛋白表达及Bcl-2/BaX升高,Bax蛋白表达降低结论:L—NA通过抑制TNF-α和IL-1β的升高,增加Bcl-2蛋白表达,降低Bax蛋白表达,调节Bcl-2/Bax平衡,对脑缺血大鼠脑神经元产生一定程度的保护作用。  相似文献   
94.
一氧化氮在炎性疼痛中的作用   总被引:1,自引:0,他引:1  
李其  洪炎国 《生命科学》2007,19(4):423-426
一氧化氮(nitric oxide,NO)是细胞内重要的信使分子和神经递质,它参与多种生命活动,包括炎性疼痛.NO对炎性疼痛的发展和维持起到了重要的作用.研究NO在疼痛中所起到的作用及其机制有利于阐明痛觉生理和发现疼痛治疗的新手段.目前研究表明,脊髓水平NO参与炎性疼痛调制的可能机制主要有NO/cGMP途径、参与调控即刻早期基因、与其他神经递质的协同作用.另外研究表明,3种类型的一氧化氮合酶(nitric oxide synthases,NOS)在炎性疼痛过程中被激活或者有不同程度的增强表达.  相似文献   
95.
Inflammatory bowel disease (IBD) represents a spectrum of diseases in which inflammation leads to acute and chronic gut injury. It is a growing health issue for which no cure exists. The pathogenesis is multifactorial with links to infectious and environmental events that trigger disease in genetically predisposed individuals. Treatment of the two major forms of IBD, Crohn's disease and ulcerative colitis, involves the reduction of inflammation with toxic immunosuppressive drugs or blocking of the pro-inflammatory effects of tumour necrosis factor-α (TNF-α) with antibodies. Here, we show that the oral administration of transgenic low-alkaloid tobacco expressing the contra-inflammatory cytokine human interleukin-10 (hIL-10) reduces the severity of colitis by down-regulating TNF-α expression directly at the sites of inflammation in IBD-susceptible IL-10−/– mice. hIL-10 expressed in plants is biologically active and displays resistance to gastrointestinal degradation. Dietary supplementation with plant tissue delivering up to 9 µg of hIL-10 daily for 4 weeks was well tolerated by treated mice. Gut histology was significantly improved relative to controls ( P =  0.002), and was correlated with a decrease in small bowel TNF-α mRNA levels and an increase in IL-2 and IL-1β mRNA levels. Transgenic plants expressing IL-10 to directly attenuate TNF-α expression at sites of inflammation in the gut may become a useful new approach in the luminal therapy of IBD.  相似文献   
96.
戴静雯  周萍萍  李素  仇华吉 《微生物学报》2022,62(10):3709-3721
天然免疫是机体通过识别自身或外部危险信号后,为维持体内稳态而逐步建立起来的一系列防御反应,当宿主细胞内的模式识别受体识别胞内病原相关分子模式后激活干扰素(interferon, IFN)、核因子-kappa B (nuclear factor-kappa B, NF-κB)和炎性小体等信号通路。IFNs在天然免疫应答中发挥重要作用,它诱导的抗病毒基因能够通过多种方式抵御病毒的感染,炎症反应则是机体自动的防御反应,能够在病毒感染机体时释放促炎性细胞因子以调控机体的免疫反应,进而发挥抗病毒作用。在病毒感染过程中,IFN信号通路与炎症反应调控网络中的关键分子如NF-κB/RelA、PKR等存在一定的交互作用,此外,IFN信号通路及其产生的细胞因子又影响其他信号通路的活化,进而调控机体的免疫应答以维持自身稳态,它们之间的交互调控失衡将会引起过度炎症反应,导致组织器官的免疫病理损伤,例如SARS-CoV-2感染机体时产生的过度炎症反应。本文综述了机体抗病毒免疫过程中干扰素信号通路与炎症反应之间的交互调控,为研发抗病毒策略提供新思路。  相似文献   
97.
粪菌移植研究的文献计量学和可视化分析   总被引:1,自引:1,他引:0  
【背景】粪菌移植是近年医学领域研究的热点,不但能够治疗消化系统疾病,而且在神经及精神系统、心血管系统相关疾病的治疗中均有不错的疗效,有着广阔的应用前景。【目的】掌握国内外粪菌移植的研究现状、热点及发展趋势,为相关领域科研工作者的研究提供参考。【方法】基于Web of Science核心数据库,通过CiteSpace对2011-2021年的年度发文量、作者、国家、期刊、被引情况和关键词等进行可视化分析。【结果】筛选后共纳入4 905篇文献,目前全球粪菌移植研究的文献数量呈快速增长趋势;美国和中国是发文量最多的国家。中国学者的总发文量虽然位居世界第二,但中心度和篇均被引频次较低,说明受关注程度及学术影响力不足,在发文质量上还有待提高;Gastroenterology是国内外学者发文量最多的期刊,Frontiers in Microbiology是中国学者发文量最多的期刊;粪菌移植呈现出多学科交叉的发展特点;粪菌移植目前的研究热点主要与肠内疾病(炎症性肠病、艰难梭菌感染)和肠外疾病(如抑郁、冠状动脉粥样硬化等)有关;粪菌移植在未成年人中的应用、对胰岛素敏感度的影响、测序技术在肠道菌群的应用及...  相似文献   
98.
In this study, the amino acid sequence and anti‐inflammatory effect of Bauhinia bauhinioides (BBL) lectin were evaluated. Tandem mass spectrometry revealed that BBL possesses 86 amino acid residues. BBL (1 mg/kg) intravenously injected in rats 30 min prior to inflammatory stimuli inhibited the cellular edema induced by carrageenan in only the second phase (21% – 3 h, 19% – 4 h) and did not alter the osmotic edema induced by dextran. BBL also inhibited carrageenan peritoneal neutrophil migration (51%), leukocyte rolling (58%) and adhesion (68%) and the neutrophil migration induced by TNF‐α (64%). These effects were reversed by the association of BBL with galactose, demonstrating that the carbohydrate‐binding domain is essential for lectin activity. In addition, BBL reduced myeloperoxidase activity (84%) and TNF‐α (68%) and IL1‐β (47%) levels. In conclusion, the present investigation demonstrated that BBL contains highly homologous isolectins, resulting in a total of 86 amino acid residues, and exhibits anti‐inflammatory activity by inhibiting neutrophil migration by reducing TNF‐α and IL1‐β levels via the lectin domain. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
99.
蛋白酶3(proteinase 3,PR3)是中性粒细胞分泌的主要丝氨酸蛋白酶之一,其生物学功能广泛,不仅能降解多种组织蛋白,还可通过加工细胞因子、受体等调控炎症反应,与慢性炎症性疾病如血管炎性肉芽肿病、慢性阻塞性肺疾病、肺囊肿性纤维症的发生发展密切相关,可能作为疾病防治靶点.本文主要综述了PR3的生物学功能及其在疾病中的可能作用机制,期望为相关疾病的防治提供新的思路.  相似文献   
100.
Quantitation of plasma lipopolysaccharides (LPSs) might be used to document Gram-negative bacterial infection. In the present work, LPS-derived 3-hydroxymyristate was extracted from plasma samples with an organic solvent, separated by reversed phase HPLC, and quantitated by MS/MS. This mass assay was combined with the limulus amebocyte lysate (LAL) bioassay to monitor neutralization of LPS activity in biological samples. The described HPLC/MS/MS method is a reliable, practical, accurate, and sensitive tool to quantitate LPS. The combination of the LAL and HPLC/MS/MS analyses provided new evidence for the intrinsic capacity of plasma lipoproteins and phospholipid transfer protein to neutralize the activity of LPS. In a subset of patients with systemic inflammatory response syndrome, with documented infection but with a negative plasma LAL test, significant amounts of LPS were measured by the HPLC/MS/MS method. Patients with the highest plasma LPS concentration were more severely ill. HPLC/MS/MS is a relevant method to quantitate endotoxin in a sample, to assess the efficacy of LPS neutralization, and to evaluate the proinflammatory potential of LPS in vivo.  相似文献   
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