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41.
The principal cause of IL-2 deficiency, a common feature of both murine lupus and human SLE, remains obscure. Recent studies of our own as well as others have shown that dehydroepiandrosterone (DHEA), an intermediate compound in testosterone synthesis, significantly up-regulates IL-2 production of T cells, and that administration of exogenous DHEA or IL-2 via a vaccinia construct to murine lupus dramatically reverses their clinical autoimmune diseases. Thus, we have examined serum levels of DHEA in patients with SLE to test whether abnormal DHEA activity is associated with IL-2 deficiency of the patients. We found that nearly all of the patients examined have very low levels of serum DHEA. The decreased DHEA levels were not simply a reflection of a long term corticosteroid treatment which may cause adrenal atrophy, since serum samples drawn at the onset of disease, which are devoid of corticosteroid treatment, also contained low levels of DHEA. In addition, exogenous DHEA restored impaired IL-2 production of T cells from patients with SLE in vitro. These results indicate that defects of IL-2 synthesis of patients with SLE are at least in part due to the low DHEA activity in the serum.  相似文献   
42.
为解决细胞内抗原应用免疫金银法染色时背景过重的问题,建立了甘氨酸二次阻断的处理方法,效果较好。  相似文献   
43.
An affinity chromatography technique was utilized to isolate and purify the receptors of Escherichia coli K88ac(+) fimbriae from the mucus of the small intestines of newborn piglets. Purified K88ac+ fimbriae were covalently immobilized onto a beaded agarose matrix (Sepharose 4B). The immobilized fimbriae were used for the affinity purification of the K88ac+ receptors. Only two major proteins were tightly and specifically bound to the immobilized fimbriae after the column containing bound receptor was washed exhaustively with a buffer containing a high concentration of salt and a detergent. The receptors were eluted as a single component at a low pH. The isolated proteins were then subjected to enzyme-linked immunosorbent assay, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and Western blot (immunoblot) analyses. The two proteins were of high purity, were responsible for nearly all of the fimbrial binding capacity of the crude mucus, and had molecular masses of 26 and 41 kDa. The method for isolation of E. coli binding proteins is simple and yields purified intestinal receptors in a single chromatographic run. The intestinal mucus of different piglets has different proportions of the two receptor proteins.  相似文献   
44.
目的:探讨川芎嗪对内毒素脂多糖(LPS)诱导的体外血脑屏障模型通透性增高的保护作用及其调控机制。方法:利用脑微血管内皮细胞与星型胶质细胞共培养建立体外大鼠血脑屏障模型,随机分为正常对照组、川芎嗪对照组、LPS干预组和川芎嗪治疗组。采用γ计数仪检测~(125)I-BSA通透量观察体外血脑屏障模型通透性的改变,Western印迹法检测紧密连接蛋白(zonula occludens-1,ZO-1)表达量的变化。结果:LPS使体外血脑屏障模型对~(125)I-BSA的通透量明显增加,脑微血管内皮细胞ZO-1蛋白表达下降,川芎嗪治疗组能明显拮抗LPS的上述作用。结论:川芎嗪对LPS诱导的体外血脑屏障通透性增高具有保护作用,其机制与它能影响血脑屏障紧密连接蛋白ZO-1表达有关。  相似文献   
45.
Burkholderia pseudomallei is the causative agent of melioidosis, an infectious disease with protean clinical manifestations. The major route of infection is thought to be through subcutaneous inoculation of contaminated soil and water, although ingestion and inhalation of contaminated aerosols are also possible. This study examines infection through the intranasal route in a murine model to mimic infection through inhalation. Two strains of mice, C57BL/6 and BALB/c, exhibit differential susceptibilities to the infection, with the C57BL/6 mice being considerably more resistant. To examine host factors that could contribute to this difference, bacterial loads and cytokine profiles in the two strains of mice were compared. We found that infected BALB/c mice exhibited higher bacterial loads in the lung and spleen and that they produced significantly higher levels of gamma interferon (IFN-gamma) in the serum than C57BL/6 mice. Although tumor necrosis factor alpha and interleukin-1 could be detected in the nasal washes and sera of both strains of mice, the production in serum was transient and much lower than that of IFN-gamma. C57BL/6 mice also exhibited memory responses to bacteria upon reinfection, with the production of serum immunoglobulin G (IgG) and mucosal IgA antibodies. Thus, it is possible that the production of systemic and mucosal antibodies is important for protection against disease in C57BL/6 mice.  相似文献   
46.
Human macrophages (M phi) from most donors respond to inoculation with Mycobacterium avium serovar 4 (M. avium) by tumor necrosis factor alpha (TNF-alpha) production, which is of critical importance for proper defense against microorganisms. An initial infection of M phi with M. avium results in an incapacity to accumulate TNF-alpha mRNA after reinfection with M. avium, indicating adaptation to a hyporesponsive state by preexposure of the cells to M. avium. Adaptation to stimulation with M. avium is abrogated by the cyclooxygenase inhibitor indomethacin. In the presence of prostaglandin E2, indomethacin-exposed, M. avium-treated M phi remain unresponsive to a subsequent M. avium stimulus to increase steady-state TNF-alpha mRNA, suggesting that prostaglandin E2 is instrumental for the adaptation to an M. avium challenge. TNF-alpha mRNA accumulation induced by a second M. avium stimulus in the presence of indomethacin is blocked by the protein tyrosine kinase inhibitor herbimycin. In contrast, the initial M phi response to M. avium is inhibited by staurosporin, an inhibitor of phospholipid Ca(2+)-dependent protein kinases, indicating that the initial and the successive TNF-alpha responses to M. avium are dependent on different mechanisms.  相似文献   
47.
目的评价骨水泥强化椎弓根螺钉固定治疗老年退行性腰椎疾病的近期临床疗效。方法回顾性分析2011年6月~2013年5月采用聚甲基丙烯酸甲酯(PMMA)骨水泥强化椎弓根螺钉固定结合后路椎体间植入聚醚醚酮(PEEK)材质椎间融合器治疗老年退行性腰椎疾病30例。所有患者术前骨密度检测均符合骨质疏松诊断(超声骨密度值测定-2.5)。结果 30例患者均顺利完成手术,术中无神经及硬膜损伤,骨水泥无严重渗漏,术后复查X线、CT显示骨水泥分布均匀。随访10~21个月,平均(16±2.11)个月,神经受压症状均得到改善。VAS评分术前(7.01±1.44)、术后6个月随访为(3.00±0.57)、末次随访为(2.23±1.19);JOA评分术前为(9.98±5.64)、术后6个月随访为(17.99±1.41)、末次随访为(18.42±1.47);ODI评分术前为(0.64±0.24)、术后6个月为(0.27±0.07)、末次随访为(0.22±0.09)。三项评分术后6个月、末次随访分别与术前对比差异有统计学意义;术后6个月和末次随访对比差异无统计学意义。末次随访时复查X线或CT显示椎弓根螺钉无松动,椎间融合器无下沉,椎间融合满意,融合率为86.7%。结论使用骨水泥强化椎弓根螺钉能够提高螺钉对伴有骨质疏松的椎体的握持力,防止椎弓根螺钉松动,保证较高的椎间融合率,是治疗老年退行性腰椎疾病一种安全而有效的手术方式。  相似文献   
48.
细胞因子对肾小球系膜细胞合成PAF的影响   总被引:1,自引:0,他引:1  
本文首先建立了血小板活化因子(PAF)的生物活性检测法,并通过体外细胞培养技术,测定了肾小球系膜细胞在经LPS、IL-1β、IL-6和TNFα的短暂刺激后,其培养上清中PAF的活性。结果发现,它们均能诱导系膜细胞合成和分泌PAF,IL-1β、IL-6和TNFα的诱生作用并呈一定的剂量依赖关系。实验提示上述因子在肾小球免疫病理损伤中,除直接作用外,也可通过诱生PAF而间接发挥作用。应用PAF拮抗剂来阻断这一途径,可能具有一定的临床应用价值。  相似文献   
49.
 目的 优化以往构建的以预防 1 型糖尿病为目的的全长谷氨酸脱羧酶(GAD)65 DNA疫苗,尝试构建GAD 65片段与IL-10双基因真核表达载体。方法 从GAD65质粒中扩增出GAD190-315片段和GAD490-570片段的cDNA,以overlap PCR法将之分别与hIL-2信号肽cDNA拼接,得到SGAD190-315、SGAD490-570融合基因。以p43.2-mIL-10质粒为模板,用PCR方法扩增出IL-10基因。将SGAD190-315、SGAD490-570融合基因分别与IL-10基因依次克隆入双启动子真核表达载体pBudCE4.1中,构建出2种双基因重组真核表达载体pBud-SGAD190-315/IL-10和pBud-SGAD490-570/IL-10。2种重组真核表达载体经测序鉴定正确后,用脂质体介导的方法转染COS-7细胞,转染后48和72 h以蛋白质印迹法检测细胞裂解产物及上清液中SGAD190-315和SGAD490-570融合基因的表达,ELISA方法检测细胞上清液中IL-10的表达。结果 核酸序列测定表明克隆的SGAD190-315、SGAD490-570融合基因和IL-10基因序列与报告序列一致。蛋白质印迹法和ELISA方法均检测到SGAD190-315/IL-10和SGAD490-570/IL-10重组真核表达载体在COS-7细胞中的表达。结论 成功构建了2种GAD65片段与IL-10双基因真核表达载体,为1型糖尿病的基因疫苗预防研究提供了实验基础。  相似文献   
50.
The critical distinction of bronchioloalveolar carcinoma (BAC), well-differentiated adenocarcinoma (WDAC) of lung, adenomatous hyperplasia (AH) and atypical adenomatous hyperplasia (AAH), is based on morphological criteria alone, and is therefore potentially subjective. We examined expression of two markers, X-linked inhibitor of apoptosis protein (XIAP), the most potent of the inhibitor of apoptosis protein (IAP) family, and p63, a marker of bronchial reserve cells (BRC) and squamous cells, in these entities. H&E slides of 37 tissue blocks from 27 patients were reviewed and classified as AH (n=7), AAH (n=8), BAC (n=9) and WDAC (n=13). Immunostaining was performed on 4 mum sections with monoclonal anti-XIAP and monoclonal anti-p63. Granular or heterogeneous cytoplasmic staining for XIAP and nuclear staining for p63 were considered positive. Neither XIAP nor p63 were detected in normal lung alveolar cells. All seven AHs were negative for XIAP and negative or focally positive for p63. All eight AAHs were positive for XIAP and displayed p63 positivity in scattered cells. All BACs displayed XIAP positivity, which ranged from focal/weak to diffuse/strong. p63 was negative in seven and focally positive in two of nine BACs. Twelve of 13 WDACs showed XIAP positivity in a similar pattern to BAC; all were negative for p63. One aberrant case diagnosed on H & E as WDAC was negative for XIAP but strongly positive for p63. Significant XIAP expression appears to be useful for distinguishing AAH from AH. Commonality of XIAP staining in AAH, BAC and WDAC supports the possibility that AAH may be a pre-malignant lesion. The rarity of p63 expression confirms previous reports and supports a nonbronchial histogenesis of these entities. In contrast, diffuse p63 staining may facilitate the identification of rare cases that may have been misclassified as alveolar in origin based on morphology but may be of BRC origin.  相似文献   
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