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81.
alpha(v)beta(3) Integrin in central nervous system tumors   总被引:1,自引:0,他引:1  
alpha(v)beta(3) Is an integrin specifically expressed in endothelial cells of newly forming blood vessels. Integrin-mediated angiogenesis is hypothesized to play a central role in the development and the progression of central nervous system neoplasms. Accordingly, it is considered a potential target for antiangiogenic therapy. In the current study, we compare the expression of alpha(v)beta(3) in ependymomas, oligodendrogliomas, pilocytic astrocytomas, medulloblastomas, and vestibular schwannomas (acoustic neuromas). Samples of 5 tumors of each of the 5 tumor types were harvested surgically and frozen. After the pathological diagnosis was confirmed, immunohistochemistry was performed using an anti- alpha(v)beta(3) monoclonal antibody (LM609). The expression of alpha(v)beta(3) was assessed using a 4-tiered (0-3) grading scheme reflecting the percentage of positively staining vessels. All vestibular schwannomas demonstrated strong (grade 3) alpha(v)beta(3) expression. The expression was uniformly prominent in Antoni B regions of the tumors. Of 5 ependymomas, 4 demonstrated uniformly strong alpha(v)beta(3). Oligodendrogliomas, medulloblastomas, and pilocytic astrocytomas demonstrated more variable alpha(v)beta(3). alpha(v)beta(3) may contribute significantly to angiogenesis in vestibular schwannomas and ependymomas. Despite the high vascular density of oligodendrogliomas, pilocytic astrocytomas, and medulloblastomas, these tumors had variable moderate alpha(v)beta(3) expression. This discrepancy suggests temporal and/or regional variability in the angiogenesis in these types of tumor. This study provides the first demonstration of alpha(v)beta(3) expression in vestibular schwannomas, medulloblastomas, and pilocytic astrocytomas.  相似文献   
82.
Following recent experimental data suggesting an aggravating effect of circulating proinflammatory cytokines on the histological lesions of IgAN, we studied changes in serum proinflammatory cytokines and their soluble receptors and antagonists in patients treated with polyvalent immunoglobulins (15 with severe nephropathy who had indicators of poor prognosis: heavy proteinuria, hypertension, altered renal function and Lee's histological grade III or IV; and 14 with moderate forms of IgAN who had permanent albuminuria > 300 mg/day and < 2000 mg/day, Lee's histological grade II and a glomerular filtration rate > 70 ml/min) in comparison with healthy controls (n = 20) and patients with non-IgA nephritides (n = 50). These were measured by means of specific immunometric assays before and after 9 months of immunoglobulin therapy. Total tumour necrosis factor (TNF) serum and IL-6 levels were elevated in IgAN patients before therapy, relative to controls, and normalized after immunoglobulin therapy. Levels of soluble TNF receptor of type I (sR55) and type II (sR75) increased on immunoglobulin therapy. TNF index α-55,75 used to assess biologically available TNF-α (ratio of total TNF-α divided by levels of soluble TNF receptors sR55 and sR75) was elevated before therapy and was below healthy control values after 9 months of immunoglobulin administration. Levels of serum IL-1 receptor antagonist were low prior to immunoglobulin administration in patients with severe forms of IgAN, and normalized on therapy. Serum interferon-gamma was unmodified. The histological activity index correlated with serum total TNF-α, TNF index α-55,75 and serum IL-6 levels, whereas proteinuria correlated with serum total TNF-α and TNF index α-55,75 but not with serum IL-6. These data suggest that the overproduction of proinflammatory cytokine is unbalanced by their natural antagonists in IgAN and Henoch–Schönlein syndrome. This process may play a role in the progression of the disease and be one of the targets of immunoglobulin therapy.  相似文献   
83.
84.
八珍汤对血虚模型小鼠造血调控因子影响的实验研究   总被引:7,自引:0,他引:7  
探讨八珍汤对由环磷酰胺引起的小鼠骨髓造血功能抑制的调控作用。采用环磷酰胺致小鼠血虚模型 ,测定八珍汤对骨髓抑制小鼠外周血象及其细胞因子产生的影响。结果表明 ,八珍汤对环磷酰胺所致血虚模型小鼠骨髓细胞有促进增殖作用 ;经八珍汤诱导制备的巨噬细胞、脾细胞、肺条件培养液和骨骼肌条件培养液能促进血虚模型小鼠骨髓细胞增殖 ,促进血虚模型小鼠骨髓基质细胞分泌肿瘤坏死因子 (TNF)。八珍汤对环磷酰胺所致化疗损伤的造血调控作用可能与直接或间接刺激造血微环境的基质细胞分泌正性和负性造血生长因子有关。  相似文献   
85.
This study investigated the long-term outcome of patients with tuberculosis (TB) as a complication of tumour necrosis factor (TNF)-α blocker therapy. All TB cases ( n  =   21) complicating TNF-α blocker therapy from French university hospitals were collated between January 2000 and September 2002. Outcome was assessed via a postal questionnaire during September 2005. The mortality rate after 4 years was 4.8%, and one patient had relapsed and six (29%) patients had recommenced TNF-α antagonist treatment, after appropriate anti-TB therapy, without reactivation. These data support the concept that TNF-α antagonists can be restarted in TB patients provided that adequate anti-TB treatment has been completed.  相似文献   
86.
We have determined cutaneous DTH reactions to SK-SD and PPD and peripheral blood lymphocyte profiles in a group of asbestos workers in two consecutive surveys. It was found that asbestosis and, to a lesser extent, the presence of ANA are significantly correlated with the lack of response to the above antigens. 83% of asbestos workers when tested at a 4 year interval fell into the same two categories of responsiveness (lack of response or response at least to one antigen).The asbestosis cases had lower total lymphocyte count as well as proportions and absolute number of E-RFC as compared to asbestos workers without asbestosis and/or ANA. Furthermore, the latter group showed the lower percentages and absolute number of E-RFC than the matched controls. The presence of ANA is also correlated with lower proportions of E-RFC. However, this is related at least in part to asbestosis.  相似文献   
87.
IL-15 is a potent T cell chemoattractant, and this cytokine and its unique α subunits, IL-15Rα, can modify immune cell expression of several T cell chemokines and their receptors. Facial nerve axotomy in mice leads to T cell migration across an intact blood–brain-barrier (BBB), and under certain conditions T cells can provide neuroprotection to injured neurons in the facial motor nucleus (FMN). Although chemokines and chemoattractant cytokines are thought to be responsible for T cell migration to the injured cell bodies, data addressing this question are lacking. This study tested the hypothesis that T cell homing to the axotomized FMN would be impaired in knockout (KO) mice with the IL-15 and IL-15Rα genes deleted, and sought to determine if microglial responsiveness and motoneuron death are affected. Both IL-15KO and IL-15RαKO mice exhibited a marked reduction in CD3+ T cells and had fewer MHC2+ activated microglia in the injured FMN than their respective WT controls at day 14 post-axotomy. Although there was a relative absence of T cell recruitment into the axotomized FMN in both knockout strains, IL-15RαKO mice had five times more motoneuron death (characterized by perineuronal microglial clusters engulfing dead motoneurons) than their WT controls, whereas dead neurons in IL-15KO did not differ from their WT controls. Further studies are needed to dissect the mechanisms that underlie these observations (e.g., central vs. peripheral immune contributions).  相似文献   
88.
饮食性缺铜、缺锌对小鼠细胞因子产生的影响   总被引:1,自引:0,他引:1  
金虹 Ha.  BM 《现代免疫学》1996,16(2):65-68
3周龄小鼠饲用6周缺铜饮食后,出现胸腺萎缩、肝脏肿大以及明显的缺铜指征,包括血清Cp活性、肝Cu含量、CCO和Cu,Zn-SOD活性明显下降。缺钢小鼠产生的TNF-α、IL-1和IL-6水平明显低于正常组小鼠。小鼠饲予7周缺锌饮食后,出现明显脱毛,虽然肝Zn含量降低不明显,但TNF-α、IL-1和IL-6活性明显降低,说明上述细胞因子是小鼠缺锌的敏感指征之一。本文结果显示正常Cu、Zn水平对TNF-α、IL-1和IL-6产生的重要性,并提示这些细胞因子的改变可能是缺铜、缺锌引起的免疫功能损害的细胞、分子学机理之一。  相似文献   
89.
Objective and Design:Previous studies demonstrated that lactoferrin (LF), given intravenously (i.v.), 24 h before lethal Escherichia coli (E. coli) infection, protects mice against mortality. The aim of this investigation was to determine whether downregulation of serum TNF alpha activity and increase of neutrophil number in the circulation and bone marrow by LF could contribute to the protective action of LF against E. coli-induced sepsis. Materials and subjects:CBA female mice, 10–12 week old, weight 20–22 g, were used. Treatment:Mice were given 10 mg LF i.v. either 2 h or 24 h before i.v. administration of lethal dose of E. coli (5 × 108). Methods:Serum activities of TNF alpha and IL-1 were determined by bioassays 2 h following E. coli or LF injection. The blood and bone marrow smears were stained with Giemsa and May-Grünwald reagents and reviewed histologically. Results:LF given 24 h before E. coli caused a 60% reduction of TNF alpha released into circulation. However, pretreatment of mice with LF 2 h before bacterial challenge resulted in strong (15 fold) increase of TNF alpha serum level. Analysis of bone marrow cell composition revealed a significant increase in neutrophil lineage cell content (myelocytes, bands and mature neutrophils) following 24 h pretreatment with LF (51.8% of the total cell count), versus PBS control (32.7%) and 2 h LF pretreatment (35.8%). The percentage of neutrophils (bands and mature forms) in the peripheral blood rose to 47.4% versus 32% and 32%, respectively. Intravenous administration of LF increased also interleukin 1 (IL-1) concentration in the circulation of noninfected mice. Conclusions:This investigation has added more information regarding the mechanism of the protective action of LF in E. coli-induced bacteremia by revealing the phenomenon of accelerated neutrophil recruitment and down-regulation of E. coli-induced TNF alpha serum level.Received 22 September 2003; returned for revision 31 October 2003; accepted by M. J. Parnham 14 January 2004  相似文献   
90.
目的构建α干扰素基因家族定向文库。方法利用D NAshuffling技术对人、鸡和猪α干扰素基因进行人工改造,结合噬菌体展示技术构建噬菌体基因改组文库,并对文库进行验证。结果构建了α干扰素基因家族定向文库,其容量为3.5×10^7pfu;测序得到了3条与猪、人α干扰素基因高度同源的序列。结论得到了1个高质量的α干扰素基因家族定向文库,为今后筛选高效的α干扰素奠定了基础。  相似文献   
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