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991.
The clinicopathological spectrum of leprosy is associated with an altered immunological reaction. The expression of adhesion molecules on endothelial cells directs the cellular traffic to sites of local skin and nerve inflammation. Soluble forms of adhesion molecules, which are released upon cytokine activation, can be detected in the circulation and may reflect ongoing tissue inflammation. We determined the serum levels of sICAM-1, sE-selectin and sL-selectin in 74 patients with leprosy (tuberculoid form, n = 23; lepromatous form, n = 36; acute leprous reaction, n = 16) and 15 healthy age- and sex-matched control donors. Patients with lepromatous leprosy had significantly higher levels of sICAM-1 (564 ± 174 versus 450 ± 92 versus 334 ± 57 ng/ml) and E-selectin (90 ± 31 versus 74 ± 29 versus 50 ± 10 ng/ml) than patients with tuberculoid leprosy and normal donors (P<0.01). No differences between groups were detected for L-selectin. Patients with leprous reactions had similar high levels to lepromatous patients. Twenty lepromatous patients were re-examined after 4 weeks of therapy. A significant decrease in sICAM-1 serum levels was observed after 1 month of anti-mycobacterial treatment, which was accompanied by a reduction of mycobacteria in skin biopsies (P<0.01). Patients with leprous reactions (n = 13) also demonstrated a drop in sICAM-1 after anti-inflammatory therapy. sE-selectin and sL-selectin serum values decreased only in lepromatous patients after therapy. It can be concluded that soluble adhesion molecules like sICAM-1 and sE-selectin are promising activity markers in patients with leprosy, which may be useful for treatment monitoring.  相似文献   
992.
Freshly isolated peripheral blood mononuclear cells (PBMC) from 10 healthy volunteers, 28 patients with rheumatoid arthritis (RA), eight patients with osteoarthritis, and five patients with ankylosing spondylitis were examined for interleukin-1 alpha (IL-1 alpha) and interleukin-1 beta (IL-1 beta) production using monoclonal antibodies and an indirect immunofluorescent method. In freshly isolated PBMC from healthy controls very few cells were stained for either IL-1 type. All 20 RA patients who were not receiving parenteral gold therapy had PBMC staining for IL-1 alpha. In these patients, up to 7.5% of PBMC showed bright IL-1 alpha staining (range 1.2-7.5%). No IL-1 beta staining was seen. These IL-1 alpha-staining cells had a dendritic morphology and the percentage of cells staining correlated well with levels of C-reactive protein, an index of disease activity in these RA patients. Significantly fewer IL-1 alpha-staining cells were present in the peripheral blood of RA patients receiving gold therapy and in the blood of patients with osteoarthritis and ankylosing spondylitis. These IL-1 alpha-containing cells, circulating in the blood of RA patients and correlating with disease activity have not been previously described. These results support the idea that IL-1 alpha plays an important role in the pathogenesis of rheumatoid inflammation.  相似文献   
993.
双特异性抗体对LAK细胞增殖和细胞毒作用影响的体外研究   总被引:3,自引:0,他引:3  
将抗CD3与抗HBs的单克隆抗体经化学偶联得到双特异性抗体,观察该双特异性抗体对LAK细胞增殖和增强细胞毒性的作用。结果显示双特异性抗体显著提高LAK细胞与2.2.15细胞结合率;促进淋巴细胞增殖。125I-UdR释放试验检测发现双特异性抗体增强LAK细胞对2.2.15细胞的细胞毒性且与抗体浓度呈正相关。进一步对抗体的特异性研究表明,加入双特异性抗体后LAK细胞对2.2.15细胞毒性作用显著高于对照组。  相似文献   
994.
BACKGROUND: Raloxifene hydrochloride is a synthetic non-steroidal drug used for the prevention and treatment of post-menopausal osteoporosis. Pre-clinical and clinical data have shown that raloxifene may have a beneficial effect on leiomyomas. The aim of this prospective single-blind, randomized, placebo-controlled clinical trial was to evaluate the effectiveness of the addition of raloxifene to GnRH analogues on uterine, leiomyoma, and non-leiomyoma sizes, and on the occurrence of leiomyoma-related symptoms. METHODS: After randomization using a computer-generated list, 100 pre-menopausal women with symptomatic uterine leiomyomas received either leuprolide acetate depot plus raloxifene 60 mg daily (group A) or leuprolide plus placebo tablet (group B) for six cycles of 28 days. At baseline and after treatment, uterine, leiomyoma and non-leiomyoma sizes, and leiomyoma-related symptoms were evaluated for each woman. Analysis was by intention-to-treat method. RESULTS: After six cycles of treatment, a significant decrease in uterine, leiomyoma, and non-leiomyoma sizes was detected in both groups in comparison with baseline. At the same time, no significant difference in uterine and non-leiomyoma sizes was observed between the groups. Leiomyoma sizes were significantly (P < 0.05) lower in group A than in group B. No difference was observed in leiomyoma-related symptoms between groups throughout the study period. CONCLUSIONS: In women treated with GnRH analogue, the raloxifene administration induces a higher reduction of leiomyoma sizes.  相似文献   
995.
Rheumatoid arthritis (RA) is an autoimmune arthritis, for which treatment options remain limited. This study investigated the potential role of adoptive cellular gene therapy as a novel means for treating the RA animal model collagen-induced arthritis (CIA). Adoptive transfer of antigen-specific T-cell hybridomas retrovirally transduced to express IL-4 1 day before booster immunization significantly reduced the number of inflamed joints. Cell transfer after clinical onset of disease had no therapeutic effect. Bioluminescence imaging showed that the hybridomas migrated to the inflamed joints, thus delivering the regulatory protein locally at the site of inflammation. The homing was, at least in part, due to chemotaxis in response to proinflammatory chemokines that are expressed in inflamed joints. There were no significant changes in the cytokine milieu of the draining lymph nodes, nor in the systemic levels of anti-collagen antibodies in treated mice. We conclude that the beneficial clinical effects observed in our model were most likely based on the local action(s) of IL-4 in the inflamed joints and that the local delivery (and effects) of regulatory cytokines, like IL-4, constitutes a novel and effective method of preventing organ-specific autoimmune disease and of minimizing systemic adverse effects.  相似文献   
996.
Anti-CD2 MoAbs have previously been shown to induce tolerance and to block B cell differentiation, T cell and monocyte activation. Since these immune functions are important in joint inflammation, we asked whether administration of the anti-CD2 MoAb OX34 has a beneficial effect on established rat adjuvant arthritis, a model of human rheumatoid arthritis, and how it affects CD2-bearing leucocyte subsets. Female Lewis rats with established adjuvant arthritis received a total of 5 mg OX34 or isotype-matched control MoAb starting on day 15 after adjuvant injection. Weight and arthritis score (AS) were measured in a blinded fashion. Peripheral blood cells were analysed for numbers of leucocyte subsets at various time points. Animals were killed on day 30 and lymphatic organs were processed for immunohistology. Clinically, OX34 treatment led to increased body weight and reduced AS. Although OX34 binds to CD4+ and CD8+ T cells in a comparable fashion, OX34 treatment reduced CD4+ T cells, but not CD8+ T cells. Among CD4+ T cells CD45RC+ (‘naive’) T cells virtually disappeared; CD45RC (‘recently activated’) T cells were slightly reduced. A reduction of CD4+ T cells was also found in the lung, liver, bone marrow, spleen and lymph nodes. Down-modulation of the CD2 molecule by OX34, again, affected CD4+ T cells, suggesting a specific signal for CD4+ but not CD8+ T cells. In conclusion, the anti-CD2 MoAb OX34 attenuates established rat adjuvant arthritis. In spite of similar binding to CD4+ and CD8+ T cells, OX34 depletes only CD4+ T cells and down-modulates the CD2 molecule on these cells. These results suggest a therapeutic benefit from CD2-directed therapy for chronic types of arthritis.  相似文献   
997.
利用重组的丙型肝炎病毒非结构区(HCVNS5)抗原建立了酶免疫试验(EIA),对25例输血后丙型肝炎进行了不同区抗体及丙氨酸转氨酶(ALT)的动态研究,同时对156例慢性丙型肝炎患者血清进行HCVRNA和抗-NS5平行检测,两者符合率为64.1%。抗-NS5抗体首次检出时间为30~575天(182.9±168.5),晚于ALT异常和其他区抗体的出现时间。在感染后1,3,6,12和24个月后抗-NS5的阳性率分别为28%,40%,52%,68%和76%。抗-NS5的动态变化类型为四种:一过性阳性、间歇性阳性、持续性阳性和2年内持续阴性  相似文献   
998.
Summary The effect of ketoconazole on adrenal androgen secretion was examined in 15 patients with elevated serum androgens. In a dose of 600 mg per day orally ketoconazole inhibited the biosynthesis of all measured androgens. The mean reduction in serum levels of dehydroepiandrosterone sulfate was 32%, of dehydroepiandrosterone 54%, of androstenedione 52%, and of testosterone 43%; mean serum levels of cortisol only fell by 19%. The reduction in serum androgen levels was first significant 24 h after beginning of treatment and persisted as long as the drug was administered. We conclude that ketoconazole inhibits adrenal androgen biosynthesis more pronouncedly than cortisol biosynthesis. This might be of clinical benefit in the treatment of hirsutism and other states of androgen hypersecretion.Abbreviations CV coefficient of variation - MV mean value - SEM standard error of the mean - f female - m male - K ketoconazole - ACTH adrenocorticotropic hormone - DHEA dehydroepiandrosterone - DHEAS dehydroepiandrosterone sulfate - A androstenedione - T testosterone - F cortisol - P progesterone - H hirsutism - C Cushing's disease - EAS ectopic ACTH syndrome - ATU adrenal tumor  相似文献   
999.
Summary The pathogenesis of the diabetic glomerular lesion is unknown. However, cumulative indirect evidence favors hemodynamic factors associated with the abnormal endocrine environment as the cause of diabetic angiopathy. Experimental evidence suggests that the increased hydrostatic pressures in capillary beds, a hallmark of the early stages of insulin-dependent diabetes, are associated with macromolecular leakage leading to the typical thickening of glomerular capillary basement membrane and increased glomerular mesangial matrix even prior to the occurrence of systemic hypertension. Patients with renal or carotid artery stenosis seem to be protected against diabetic nephropathy and retinopathy on the stenosed side. The first signal of diabetic nephropathy even before deterioration of the renal function is microalbuminuria detected by sensitive methods such as radioimmunoassay. Not only in hypertensive, but even in normotensive diabetic patients with microalbuminuria antihypertensive therapy has been shown to reduce albumin excretion rate and to slow the progression of diabetic nephropathy. Once overt diabetic nephropathy has been established, hypertension is a constant accompaniment of the disease. Thus, hypertension may be a cause as well as a result of diabetic nephropathy. Tight control of blood sugar in close association with antihypertensive treatment reducing blood pressure to a lower normal limit, possibly with agents that specifically decrease glomerular capillary hydraulic pressure are the corner stone in protection against progression of the diabetic angiopathy.Abbreviations ECF extracellular fluid - ESRD end-stage renal disease  相似文献   
1000.
The theoretical possibility of applying gene transfer methodologies to the human germline is explored. Transgenic methods for genetically manipulating embryos may in principle be applied to humans. In particular, microinjection of retroviral vector appears to hold the greatest promise, with transgenic primates already obtained from this approach. Sperm-mediated gene transfer offers potentially the easiest route to the human germline, however the requisite methodology is presently underdeveloped. Nuclear transfer (cloning) offers an alternative approach to germline genetic modification, however there are major health concerns associated with current nuclear transfer methods. It is concluded that human germline gene therapy remains for all practical purposes a future possibility that must await significant and important advances in gene transfer technology.  相似文献   
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