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91.
92.
UDP-glucose dehydrogenase (UGDH) catalyzes the formation of UDP-glucuronate. Glucuronate represents an integral component of the glycosaminoglycan, hyaluronan, which accumulates in orbital Graves disease. Here we report that orbital fibroblasts express higher levels of UGDH than do those from skin. This is a consequence of greater UGDH gene promoter activity and more abundant steady-state UGDH mRNA. Six Sp1 sites located in the proximal 550 bp of the UGDH gene promoter appear to determine basal promoter activity, as does a previously unrecognized 49-bp sequence spanning -1436 nucleotides (nt) and -1388 nt that negatively affects activity. Nuclear Sp1 protein is more abundant in orbital fibroblasts, and its binding to specific sites on DNA is greater than that in dermal fibroblasts. Mutating each of these Sp1 sites in a UGDH gene promoter fragment, extending from -1387 to +71 nt and fused to a luciferase reporter, results in divergent activities when transfected in orbital and dermal fibroblasts. Reducing Sp1 attenuated UGDH gene promoter activity, lowered steady-state UGDH mRNA levels, and reduced UGDH enzyme activity. Targeting Sp1 and UGDH with specific siRNAs also lowered hyaluronan synthase-1 (HAS-1) and HAS-2 levels and reduced hyaluronan accumulation in orbital fibroblasts. These findings suggest that orbital fibroblasts express high levels of UGDH in an anatomic-specific manner, apparently the result of greater constitutive Sp1. These high UGDH levels may underlie susceptibility of the orbit to localized overproduction of hyaluronan in Graves disease.  相似文献   
93.
Mouse mast cell protease-4 (mMCP-4) has been linked to autoimmune and inflammatory diseases, although the exact mechanisms underlying its role in these pathological conditions remain unclear. Here, we have found that mMCP-4 is critical in a mouse model of the autoimmune skin blistering disease bullous pemphigoid (BP). Mice lacking mMCP-4 were resistant to experimental BP. Complement activation, mast cell (MC) degranulation, and the early phase of neutrophil (PMN) recruitment occurred comparably in mMCP-4(-/-) and WT mice. However, without mMCP-4, activation of matrix metalloproteinase (MMP)-9 was impaired in cultured mMCP-4(-/-) MCs and in the skin of pathogenic IgG-injected mMCP-4(-/-) mice. MMP-9 activation was not fully restored by local reconstitution with WT or mMCP-4(-/-) PMNs. Local reconstitution with mMCP-4(+/+) MCs, but not with mMCP-4(-/-) MCs, restored blistering, MMP-9 activation, and PMN recruitment in mMCP-4(-/-) mice. mMCP-4 also degraded the hemidesmosomal transmembrane protein BP180 both in the skin and in vitro. These results demonstrate that mMCP-4 plays two different roles in the pathogenesis of experimental BP, by both activating MMP-9 and by cleaving BP180, leading to injury of the hemidesmosomes and extracellular matrix of the basement membrane zone.  相似文献   
94.

Objective

Chronic pancreatitis is a gradual, long-term inflammation of the pancreas that results in alteration of its normal structure and function. The study aims to investigate the role of − 308 (G/A) polymorphism of TNF-α gene in chronic pancreatitis.

Material and methods

A total of 200 subjects were included in this case–control study. A total of 100 in patients admitted in the Gastroenterology Unit of Gandhi Hospital and Osmania General Hospital, Hyderabad were included in the present study. An equal number of healthy control subjects were randomly selected for the study. The genotyping of TNF-α gene was carried out by tetra-primer ARMS PCR followed by gel electrophoresis. The TNF-α levels were assayed by enzyme-linked immunosorbent assay.

Results

A significant variation with respect to the genotypic and allelic distribution in the disease group when compared to control subjects [OR = 2.001 (1.33–3.005), p < 0.0001**] was observed. Subjects homozygous for the A allele had higher TNF-α levels compared to G allele.

Conclusion

The present study revealed a significant association of the TNF-α gene promoter polymorphism with chronic pancreatitis. Thus, TNF-α genotype can be considered as one of the biological markers in the etiology of chronic pancreatitis.  相似文献   
95.
自身免疫性溶血性贫血(AIHI)按照自身抗体作用于红细胞时所需的温度分为温抗体型AIHI(WAIHI)和冷抗体型AIHI(CAIHI),以WAIHI居多,并且多为继发性。WAIHI的发病与温度没有显著的相关关系,其发病是由各种原因引起的免疫机制变异,主要包括基因遗传因素、自身免疫调节异常及免疫因素等,导致针对自身红细胞的抗体产生,再与红细胞膜表面抗原结合,它是一种会使自身红细胞破坏或者缩短寿命的比较难以治疗的贫血,目前治疗AIHI首选疗法为肾上腺皮质激素(激素),有效率可达80%,大剂量静脉注射丙种球蛋白(IVIG)、输血、切除脾等方法的使用也在实践中逐渐增多,并且疗效可观。近年来对温抗体型自身免疫性溶血性贫血的诊治进展的研究越来越多。  相似文献   
96.
Abdominal paracentesis drainage (APD), as an effective treatment of severe acute pancreatitis (SAP) in clinical settings, can ameliorate intestinal barrier damage and the overall severity of SAP. However, the mechanism underlying therapeutic effects of APD on damaged intestinal mucosal barrier during SAP is still unclear. Here, SAP was induced by injecting 5% Na-taurocholate retrograde into the biliopancreatic duct of rats to confirm the benefits of APD on enteral injury of SAP and further explore the possible mechanism. Abdominal catheter was placed after SAP was induced in APD group. As control group, the sham group received no operation except abdominal opening and closure. By comparing changes among control group, sham group, and APD group, APD treatment obviously lowered the intestinal damage and reduced the permeation of intestinal mucosal barrier, which was evidenced by intestinal H&E staining, enteral expression of tight junction proteins, intestinal apoptosis measurement and detection of serum diamine oxidase, intestinal fatty acid binding protein and D-lactic acid. Furthermore, we found that APD polarized intestinal macrophages toward M2 phenotype by the determination of immunofluorescence and western blotting, and this accounts for the benefits of APD for intestinal injury in SAP. Importantly, the protective effect against intestinal injury by APD treatment was mediated through the inhibited ASK1/JNK pathway. In summary, APD improved the intestinal mucosal barrier damage in rats with SAP through an increasing portion of M2 phenotype macrophages in intestine via inhibiting ASK1/JNK pathway.  相似文献   
97.
目的:大量研究表明重症急性胰腺炎(SAP)患者血清中高浓度IL-6和肠黏膜低表达的紧密连接蛋白可促进内毒素移位的发生。本文主要研究重症胰腺炎患者血清IL-6水平对内毒素移位和肠黏膜紧密连接蛋白表达的影响。方法:50例重症胰腺炎患者,其中12例在患病早期因结肠受累合并腹胀,对12例结肠受累患者应用结肠镜行结肠灌洗进行腹腔减压,同时取结肠黏膜进行活组织检查。所有病人在治疗的第3天,第7天,第10天,第14天抽取外周静脉血。40例健康志愿者作为对照组。应用ELISA方法检测血清IL-6水平,鲎试验(LAL)方法检测血清内毒素含量,应用免疫荧光和Western blotting方法检测肠黏膜紧密连接蛋白表达水平。结果:SAP患者血清IL-6和内毒素含量明显高于健康对照组,而结肠黏膜紧密连接蛋白表达低于对照组;在临床治疗过程中,早期SAP患者血清IL-6和内毒素水平高于晚期(P值均0.05)。SAP早期血清高浓度的IL-6与结肠黏膜紧密连接蛋白的低表达具有相关性,差异有统计学意义(r=0.735,P0.05)。结论:血清IL-6水平可作为早期评价重症急性胰腺炎严重程度的一项指标,IL-6水平与重症急性胰腺炎临床病程有相关性,可能导致肠道内毒素移位。  相似文献   
98.
目的:探讨经鼻空肠管早期行肠内营养(EN)在重症急性胰腺炎(S AP)治疗中的作用。方法:40例SAP患者随机分为治疗组和对照组,每组各20例,对照组给予常规治疗,治疗组在常规治疗的基础上加用肠内营养。观察两组治疗前后血清白蛋白和淀粉酶水平、血浆内毒素及肿瘤坏死因子TNF-α水平的变化情况。考察治愈率症、感染率、病死率、平均住院时间及费用。结果:治疗组患者行肠内营养后,血浆内毒素、TNF-α下降速度明显快于对照组P<0.05,感染率、平均住院时间与费用明显降低。结论:EN能改善ASP患者的营养状况,改善肠道黏膜屏障及降低炎性细胞因子分泌来加强治疗效果,是SAP重要治疗手段。  相似文献   
99.
摘要 目的:探讨胆囊结石患者结石形态学特征及血浆脂多糖(LPS)水平与急性胆源性胰腺炎(ABP)的关系。方法:选取2015年10月~2018年9月期间武汉大学人民医院收治的胆囊结石患者164例为研究对象,分析结石形态学特征与并发ABP的关系,同时采用Logistic回归分析ABP发生的危险因素。将所有患者根据LPS水平分为低LPS组(n=65,<10 pg/mL)以及高LPS组(n=99,≥10 pg/mL),分析血浆LPS水平对不同结石大小、不同总胆固醇(TG)水平患者并发ABP的影响。结果:多发胆囊结石、球状结石、<3 mm结石、软碎型结石患者并发ABP的概率明显高于单发胆囊结石、不规则状结石或泥沙状结石、3~10 mm结石或>10 mm结石、硬型结石或胶冻型结石(P<0.05)。Logistic回归分析结果显示,多发胆囊结石、球状结石、<3 mm结石以及软碎型结石均是ABP发生的高危因素(P<0.05)。当患者处于高TG水平时,高LPS组并发ABP的概率高于低LPS组(P<0.05),在细小结石患者中,高LPS组并发ABP的概率高于低LPS组(P<0.05)。结论:依据结石形态学特征可对胆囊结石患者并发ABP的可能性作出早期的判断,同时血浆LPS水平升高是高TG以及细小胆囊结石患者易并发ABP的重要因素之一。  相似文献   
100.
The discovery of antibiotics is the miracle of modern medicine,which has contributed greatly to the protection of human health.However,in despite of medical advances to date,some quite inexplicable modern diseases are still haunting us.These chronic diseases are less fierce in fatality,but more permanently compromise the quality of patients′lives.In this paper,the relevant background knowledge about antibiotics were introduced and the relationship between antibiotics and several common chronic diseases was analyzed,in order to promote the rational use of antibiotics and the correct view on antibiotics.  相似文献   
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