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991.
伊贝沙坦对血管紧张素Ⅱ所致心肌细胞蛋白质合成和肌球蛋白重链表达的影响 总被引:2,自引:0,他引:2
目的 观察伊贝沙坦对血管紧张素Ⅱ(AngⅡ)所致心肌细胞中蛋白质合成速率及肌球蛋白重链(MHC)基因表达改变的影响.方法 以AngⅡ及伊贝沙坦分别或同时作用于培养的细胞.采用放射性同位素[^3H]-leu掺入法检测培养心肌细胞蛋白质合成速率.应用荧光定量PCR方法检测心肌细胞心房利钠肽因子(ANF)以及α-MHC、β-MHC的表达.结果 AngⅡ处理使心肌细胞中[^3H]-Leu掺人增加(P<0.05),同时ANF mRNA的表达明显高于正常(P<0.05);α-MHC mRNA的表达显著低于正常(P<0.05),而β-MHC mRNA的表达显著高于正常(P<0.05),α-MHC/β-MHC的比值下降(P<0.05).当伊贝沙坦与AngⅡ共同作用于培养的心肌细胞时,与AngⅡ组比较,[^3H]-Leu的掺入明显下降(P<0.05),与正常组比无统计学意义(P>0.05);同时ANF的表达下降,与正常组比无统计学意义(P>0.05);心肌细胞中α-MHC的表达明显增高(P<0.05),而β-MHCmRNA的表达显著降低(P<0.05),α-MHC/β-MHC的比值上升(P<0.05).结论 伊贝沙坦能抑制AngⅡ所致的心肌细胞肥大和细胞中α-MHC向β-MHC表达的转换. 相似文献
992.
I. N. Nifontova D. A. Svinareva I. L. Chertkov N. I. Drize V. G. Savchenko 《Bulletin of experimental biology and medicine》2008,145(5):629-633
We studied the effects of chronic administration of granulocyte colony-stimulating factor in nonmobilizing doses to mice.
Over 18 months of the study, 55% animals of the treatment group died of unknown cause, blood diseases and tumors were found
in 20% mice, and in 5% animals pathological changes were absent. Control mice had no diseases (normal values of total and
differential leukocyte count). The diagnoses made over the first 7 months mainly included myeloproliferative diseases. Solid
tumors were found at later terms. Suppurative inflammation at the site of injection was observed in all mice after 3-month
treatment with granulocyte colony-stimulating factor. Our results indicate that chronic administration of granulocyte colony-stimulating
factor in low doses leads to the development of etiologically different tumors and sharply reduced animal life span. The use
of granulocyte colony-stimulating factor during allogeneic transplantation of hemopoietic stem cells can be hazardous for
donors.
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 5, pp. 568–573, May, 2008 相似文献
993.
目的通过对无精子症和严重少精子症患者Y染色体AZF微缺失的检测,确定AZF微缺失的发生率及高发位点;同时,对正常生育男性、无精子症及严重少精子症患者进行sY254、sY255点突变检测,从分子水平探讨精子发生的机制,建立基因型与表型的关系。方法多重PCR技术对Y染色体上AZF 4个区域内的15个序列标签位点进行微缺失检测,采用SSCP方法进行sY254、sY255点突变检测;结果无精子症和严重少精子症患者Y染色体AZF微缺失率分别为9.80%和9.68%,显著高于少精子症组的3.34%(P<0.05);其中sY152、sY239、sY243、sY254、sY255在Y染色体上的位置相互毗邻,其联合缺失39例,占总缺失率的65.0%,AZFb+AZFd+AZFc联合缺失的有8人,占总缺失的13.3%;本研究中,正常生育男性、无精子症及严重少精子症患者均未发现sY254、sY255的点突变。结论Y染色体AZF微缺失是导致无精子症和严重少精子症的重要因素,sY152、sY239、sY243、sY254、sY255联合缺失是AZF的缺失热点;未发现sY254、sY255点突变。 相似文献
994.
B. Denis A. Lefort R. M. Flipo F. Tubach M. Lemann P. Ravaud D. Salmon X. Mariette O. Lortholary 《Clinical microbiology and infection》2008,14(2):183-186
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
995.
IgE Anti-IgG Antibodies in Patients with Juvenile and Adult Rheumatoid Arthritis Including Felty's Syndrome 总被引:1,自引:0,他引:1
Anti-IgG; antihodies (anti-IgG) of the IgE class were studied in sera from patients with juvenile rheumatoid arthritis (JRA). rheumatoid arthritis (RA) and patients with Felty's syndrome (FS) by use of an indirect immunofluorescence technique. Forty-two percent of 26 patients with JRA had IgE anti-IgG in serum all in low titers. Positive reactions prevailed in patients with multiple joint involvement. Sixty-three percent of 30 patients with RA and 80% of 20 patients with FS had IgE anti-IgG, the titers found in FS patients being significantly higher. In JRA and FS patients the IgE anti-IgG titers were correlated to the titers of anti-IgG of the IgG class, and for FS patients also with the IgM and IgA classes of anti-IgG. In six of 10 patients with RA the synovial fluid samples from both knees contained IgE anti-IgG. In four of these patients the titers of IgE anti-IgG were higher than in the corresponding serum sample, pointing to a local production. After G-200 Sephadex chromatography IgE anti-IgG were demonstrated in the void volume indicating the presence of these autoantibodies in immune complexes. IgE anti-IgG may be involved in the pathogenesis of JRA and RA by eliciting Type I and III reactions. 相似文献
996.
Dialysable transfer factor (TF) was given in 10 paediatric patients with severe atopic dermatitis (AD). Ten patients with AD, matched for age and severity of disease, served as controls.
Prior to the therapy with TF and at weekly intervals thereafter, T- and B-cells in the blood, PHA-stimulation, total IgE and specific IgE antibodies to inhalant and food antigens were determined. Therapy with TF was followed by IgE depression in 8/10 patients and was most pronounced in three patients with initially high levels. Some decrease of IgE levels was seen in four controls also, none of them, however, fell to normal levels as was seen in two of the treated patients.
Specific IgE levels decreased slightly, but always remained within the pathological range. T-cell counts in the blood increased in 2/10 cases as well as PHA-stimulation. B-cell counts remained within normal limits. Clinical improvement was seen in one patient, five improved slightly and four remained unchanged.
Our results indicate, that transfer factor can lower total IgE levels in cases with atopic dermatis. The effect is most marked in patients with high total IgE levels. Skin involvement, however, does not closely follow in vitro findings. 相似文献
Prior to the therapy with TF and at weekly intervals thereafter, T- and B-cells in the blood, PHA-stimulation, total IgE and specific IgE antibodies to inhalant and food antigens were determined. Therapy with TF was followed by IgE depression in 8/10 patients and was most pronounced in three patients with initially high levels. Some decrease of IgE levels was seen in four controls also, none of them, however, fell to normal levels as was seen in two of the treated patients.
Specific IgE levels decreased slightly, but always remained within the pathological range. T-cell counts in the blood increased in 2/10 cases as well as PHA-stimulation. B-cell counts remained within normal limits. Clinical improvement was seen in one patient, five improved slightly and four remained unchanged.
Our results indicate, that transfer factor can lower total IgE levels in cases with atopic dermatis. The effect is most marked in patients with high total IgE levels. Skin involvement, however, does not closely follow in vitro findings. 相似文献
997.
Anterior pituitary cells of the GH line, which secrete prolactin spontaneously, showed spontaneous action potential activity. Thyrotrophin releasing factor, which increases secretion in these cells, caused a prompt increase of action potential frequency. Potassium, another secretagogue, depolarized the cells and sometimes initiated a burst of action potentials at the onset of this effect. The action potentials persisted in tetrodotoxin-containing and Na-free media, but were suppressed by the Ca-channel blocker, methoxyverapamil. Moreover, elevating the extracellular Ca2+ concentration increased the amplitude of the action potentials. These action potentials therefore have a prominent Ca component. This endows them with a particular interest since secretory activity of these cells is known to be dependent on extracellular Ca2+. Ba2+, which can substitute for Ca2+ in maintaining secretion, also substituted for Ca2+ in the maintenance of the action potentials. In addition, Ba2+ prolonged action potentials remarkably: tetraethylammonium was less effective in this regard.The several parallels between known secretory behaviour and electrical phenomena encourage the view that analysis of electrical activity in anterior pituitary cells may provide useful clues to events involved in stimulus-secretion coupling and in the secretory control exerted by the brain. 相似文献
998.
D W Bradley E H Cook J E Maynard K A McCaustland J W Ebert G H Dolana R A Petzel R J Kantor A Heilbrunn H A Fields B L Murphy 《Journal of medical virology》1979,3(4):253-269
Non-A, non-B viral hepatitis was transmitted to four colony-born chimpanzees by infusion of three lots of antihemophilic factor (factor VIII) implicated in the transmission of non-A, non-B hepatitis to two human recipients. All four inoculated animals showed histopathological evidence of viral hepatitis, and all demonstrated significant ALT elevations between seven and one-half weeks after inoculation. Acute-phase plasma from one of the infected chimpanzees (no. 771) was shown to induce non-A, non-B hepatitis in two other chimpanzees approximately three weeks after their inoculation. In addition, an acute-phase open liver wedge biopsy obtained from animal no. 771 was processed and examined by immune electron microscopy (IEM) for virus-like particles with convalescent serum from a serologically confirmed case of non-A, non-B hepatitis. Twenty-five to 30 nm (mean = 27 nm) diameter virus-like particles that were either "full" or "empty" were identified in this liver preparation by IEM. Two additional chimpanzees inoculated with a cesium chloride gradient fraction of an isopycnically banded liver homogenate (animal no. 771) also developed elevated ALT activity two to two and one-half weeks later. Our findings have experimentally verified that commercially produced factor VIII materials can induce non-A, non-B hepatitis in champanzees and that the disease can be subpassaged in these animals by inoculation of either acute-phase plasma or liver. These results also provide evidence for the association of 27 nm-diameter virus-like particles with non-A, non-B viral hepatitis. 相似文献
999.
目的:检测宫内发育迟缓(IUGR)儿脐血胰岛素样生长因子-I(IGF-I)、胰岛素样生长因子结合蛋白-3(IGFBP-3)水平,分析这些指标的变化程度与胎儿期生长的关系。方法:将86例脐血标本分为IUGR(即小于胎龄儿)组和适于胎龄儿(AGA)组。采用放射免疫分析(RIA)测定IGF-I水平,免疫放射分析(IR-MA)测定IGFBP-3水平。两组间比较用t检验,两变量之间的关系采用相关回归分析。结果:与AGA组相比,IUGR组脐血IGF-I和IGFBP-3水平显著降低(P均〈0.01);IGF-I、IGFBP-3均随胎龄及出生体重增加而增加(P均〈0.01);IGFBP-3与IGF-I呈正相关(P〈0.01)。结论:脐血IGF-I和IGFBP-3的含量可作为判断新生儿生长发育程度的一项客观指标。 相似文献
1000.
Effect of rectal administration of rebamipide on dextran sulfate sodium-induced colitis: Role of hepatocyte growth factor 总被引:1,自引:0,他引:1
R. Murai T. Kanbe T. Mukoyama T. Shimomura K. Hashiguchi Y. Yoshida H. Tsuchiya Y. Hoshikawa A. Kurimasa G. Shiota 《Inflammation research》2007,56(6):240-245
Objective and design: Since rebamipide is effective for the treatment of ulcerative colitis (UC), we examined the involvement of hepatocyte growth
factor (HGF) in the action of rebamipide.
Materials: Fifty-five and forty female Balb/c mice, respectively, were used in Exp. 1 and 2.
Treatment: 50 mg/kg/day rebamipide (Exp. 1) and 1 × 107 pfu pAxCAHGF (the CAG promoter-driving HGF gene in adenovirus vector) (Exp. 2) were intrarectally introduced after induction
of colitis by 4 % dextran sulfate sodium (DSS).
Methods: Therapeutic effects were assessed by cell proliferation and apoptosis.
Results: Rebamipide caused proliferation of epithelial cells at 10 days after treatment, and decreased apoptosis at 10, 14 and 21 days,
compared with controls. Expression of HGF was greatly increased in rebamipide-treated mice. pAxCAHGF caused cell proliferation
and apoptosis, which showed the same pattern as with rebamipide treatment.
Conclusions: Rectal administration of rebamipide is effective for DSS-induced colitis in association with induction of HGF.
Received 17 June 2006; returned for revision 23 August 2006; returned for final revision 29 October 2006; accepted by I. Ahnfelt-R?nne
14 December 2006 相似文献