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991.
To detect numerical chromosomal abnormalities (NCA) in malignant cells on body fluids, Fluorescence in situ hybridization (FISH) technique was tested in clinical specimens from patients with metastatic disease. Directly labeled DNA probes specific for chromosomes 8, 12, X, and Y (Imagenetics, Naperville, IL) were used for in situ hybridization to interphase cell nuclei. Fifteen body fluids (BF) from various sites were studied. Based initially on the Papanicolaou-stained slides, there were seven malignant and eight benign samples. Blind analysis (200 cells/sample) showed that all benign samples had a normal number of chromosomes, whereas six of seven malignant samples showed different NCA comprising 5-60% of the cell population ranging from three to 10 chromosome signals per cell. We conclude that interphase cytogenetic cell analysis of BF by FISH is: (1) feasible and gives superior signals for detection of NCA, (2) helpful in detecting malignant cells, (3) relatively simple with a turnaround time of less than 24 hr. This method may have diagnostic and prognostic application in the study of the biologic behavior of malignant neoplasms. 相似文献
992.
Israel Shapiro Zvi Borochowitz Shimon Degani Hanna Dar Izu Ibschitz Mordechai Sharf 《American journal of medical genetics. Part A》1992,43(3):602-605
A diagnosis of the Neu-Laxova syndrome (NLS) was made by ultrasonography at 32 wks of gestation. Ultrasonographic examination showed intrauterine growth retardation (IUGR), Dandy-Walker anomaly, choroid plexus cysts, receding forehead and microcephaly, bilateral cataract without prominent eyes, scalp edema with no generalized edema, retrognathia, curved penis, and flexion deformities of limbs. The findings in this case are consistent with NLS; however, they did not fit any of Curry's [1982] groups. Massive swelling of hands and feet were among the main manifestations in classic NLS cases. In the case presented herein, edema was noted only in the scalp. This might shed further light on the question of variability vs. heterogeneity in the NLS. This case shows the existing possibility of an early diagnosis of NLS and adds Dandy-Walker anomaly and choroid plexus cysts as new findings to this syndrome. © 1992 Wiley-Liss, Inc. 相似文献
993.
A prospective observational study was performed on 488 women with haemoglobin >/=10 g/dl at booking to examine the relationship between serum ferritin concentration quartiles at 28-30 weeks gestation with maternal characteristics, pregnancy complications and infant outcome. While there was no difference in the maternal characteristics or gestational age, the infant size decreased significantly and progressively from the lowest to the highest quartile. Despite a significant difference in the incidence of multiparous women, there was no difference in the incidence of most complications except for prelabour rupture of the membranes and infant admission to the neonatal unit. Compared with the other three quartiles, the highest quartile was associated with increased risk for preterm delivery and neonatal asphyxia, while the lowest quartile was associated with decreased risk of pre-eclampsia, prelabour rupture of the membranes, and infant admission to the neonatal unit. Overall, ferritin quartiles were correlated with other parameters of iron status and red cell indices, and ferritin concentration was inversely correlated with infant birthweight. Our findings suggested that maternal ferritin concentration is primarily a reflection of maternal iron status, and a high level is associated with unfavourable outcome. The rationale of routine iron supplementation in non-anaemic women needs to be re-examined. 相似文献
994.
Armin Kurtz Roberto Della Bruna Holger Scholz Wolfgang Baier 《Pflügers Archiv : European journal of physiology》1991,419(1):32-37
In this study we have examined a potential role of the sodium/proton exchange system in the regulation of renin secretion. We found that the inhibitors of the Na+/H+ antiport, amiloride (1 mM) and ethylisopro-pylamiloride (EIPA, 50 M), led to a 125% increase of renin secretion from cultured mouse juxtaglomerular cells. The stimulatory effect of EIPA on renin secretion was dependent on the extracellular concentrations of sodium and hydrogen ions. While lowering the extracellular pH from 7.3 to 7.0, and lowering [Na+]e from 130 mM to 5 mM had no effect on basal renin release, it markedly attenuated or even blunted the effect of EIPA on renin secretion. The stimulatory effect of forskolin on renin secretion, however, was not altered by decreases of extracellular pH and of sodium. Inhibition of basal renin release was achieved with angiotensin II (1 M). In the presence of EIPA the inhibitory effect angiotensin II was markedly attenuated. Although effective on renin secretion, neither amiloride nor EIPA exerted a significant effect on the de novo synthesis of renin in cultured mouse JG cells. These findings are compatible with the idea that an amiloride-sensitive transport process, presumably the Na+/H+ exchanger, acts indirectly as an inhibitory signal transduction system for renin secretion from renal juxtaglomerular cells. 相似文献
995.
Sequence analysis of cDNAs for the human and bovine ATP synthase β subunit: mitochondrial DNA genes sustain seventeen times more mutations 总被引:19,自引:0,他引:19
Douglas C. Wallace Jianhong Ye S. Nicolas Neckelmann Gurparkash Singh Keith A. Webster Barry D. Greenberg 《Current genetics》1987,12(2):81-90
We have cloned and sequenced human and bovine cDNAs for the subunit of the ATP synthase (ATP-synß), a nuclear DNA (nDNA) encoded oxidative phosphorylation (OXPHOS) gene. The two cDNAs were found to share 99% amino acid homology and 94% nucleotide homology. The evolutionary rate of ATPsynß was then compared with that of two mitochondrial DNA (mtDNA) ATP synthase genes (ATPase 6 and 8), seven other mtDNA OXPHOS genes, and a number of nuclear genes. The synonymous substitution rate for ATPsynß proved to be 1.9 × 10–9 substitutions per site per year (substitutions × site–1 × year–1) (SSY). This is less than 1/2 that of the average nDNA gene, 1/12 the rate of ATPase 6 and 8, and 1/17 the rate of the average mtDNA gene. The synonymous and replacement substitution rates were used to calculate a new parameter, the selective constraint ratio. This revealed that even the most variable mtDNA protein was more constrained than the average nDNA protein. Thus, the high substitution mutation rate and strong selective constraints of mammalian mtDNA proteins suggest that mtDNA mutations may result in a disproportionately large number of human hereditary diseases of OXPHOS. 相似文献
996.
ST2作为Th2细胞亚群标志以及其与支气管哮喘的关系的研究 总被引:2,自引:0,他引:2
各自主要分泌IFN γ和IL 4的Th1和Th2亚群 ,与临床疾病的关系十分密切。如何从表面标志上加以区分是一项迫切需要解决的问题。ST2是近年来提出的Th2细胞的稳定标志物。本工作在体外成功地诱导人脐带血T细胞向Th1或Th2分化的基础上 ,应用逆转录PCR分析了ST2mRNA的表达特点。证实ST2在人Th2细胞上的选择性表达。为了探索ST2、Th2与支气管哮喘的关系 ,本工作进一步检测了正常人和支气管哮喘患者外周血单个核细胞中 β actin、ST2以及IFN γ和IL 4的mRNA水平。结果显示 :支气管哮喘患者ST2mRNA水平升高 ,IL 4水平也明显升高 ,但IFN γ无变化。这提示ST2作为Th2细胞的标志物 ,有可能成为Th2极化性疾病如哮喘发病机制研究的一个参考性标志 ,至于ST2是否有可能作为治疗的靶分子 ,有待进一步探讨 相似文献
997.
Bonnet F Savès M Morlat PH Droz C Chêne G Peuchant E Bernard N Lacoste D Salamon R Beylot J 《Journal of clinical immunology》2002,22(2):75-82
We assessed the correlations between some plasma markers of immune activation (soluble receptors of interleukin 2 (sIL2-R) and TNFp75 (sTNFII-R) and usual markers of HIV infection in patients treated with protease-inhibitors (PI). Forty-six PI-naive HIV-1-infected adults were included in a 1-year prospective cohort from the initiation of a PI-containing regimen (M0). Measurements of CD4+cell count, plasma HIV-RNA, sIL2-R and sTNFII-R were performed at M0, M6, and M12. The evolution of sIL2-R from baseline to M12 was significantly different between immunological responders (IR) (CD4+count above 200/mm3 for subject having less than 200 CD4 +/mm3 at inclusion, or increase of at least 50 CD4+/mm3 for others) (58 UI/ml) and non-IR (+28 UI/ml) (P =0.01). The evolution of sTNFII-R between M0 and M12 was significantly different between virological responders (VR) (plasma HIV-1 RNA less than 500 copies/ml at M12) (–2.5 ng/ml) and non-VR (+0.2 ng/ml) (P =0.02). Our study shows significative correlations between the evolutions of soluble interleukin-2 and TNFR-II receptors and those of CD4+T-lymphocytes or HIV-RNA responses in patients under HAART. 相似文献
998.
目的 探讨聚乳酸.羟基乙酸共聚物[poly(D,L-lactic-co-glycolic)acid,PLGA]包裹的卵清蛋白(OVA)纳米癌苗(POM)对哮喘小鼠的免疫治疗效果.方法 包裹不同剂量(低、中、高)的OVA纳米粒子和对照(OVA、空白纳米粒子、PBS)通过皮下注射给予小鼠,再用OVA进行致敏和激发,通过肺组织学、支气管肺泡灌洗液(BALF)细胞计数、测定BALF和脾细胞培养上清液中细胞因子的含量,观察小鼠呼吸道炎症和免疫学改变.结果 肺部组织学和BALF中细胞计数结果显示,与PBS对照组相比,OVA治疗组、中剂量和高剂量OVA纳米组的肺部嗜酸性浸润显著减轻,BALF中总细胞和嗜酸性细胞显著减少.卸胞因子测定结果显示,与PBS对照组相比,中、高剂量OVA纳米组的BALF和脾细胞培养上清液中IFN-γ显著升高,Ⅱ,4水平显著降低.OVA治疗组中IL-4水平显著下降,而IFN-γ水平无显著差异.结论 OVA纳米疫苗可预防哮喘嗜酸性气道炎症,其可能的机制之一是调节了过敏性哮喘的Th1/Th2失平衡反应. 相似文献
999.
1000.
Increased c-Fos/activator protein-1 confers resistance against anergy induction on antigen-specific T cell 总被引:1,自引:0,他引:1
Kawasaki H Nakata Y Suzuki G Chihara K Tokuhisa T Shiozawa S 《International immunology》1999,11(12):1873-1880
We have studied the contribution of c-Fos/activator protein-1 (AP-1) to antigen-specific T cell response with reference to T cell anergy by increasing c-Fos/AP-1 in vivo and in vitro. First, after injection of a high dose of staphylococcus enterotoxin B (SEB), clonal deletion of SEB-reactive V(beta)8(+) CD4 T cells occurred both in control B6 and H2-c-fos transgenic (fos) mice, whereas proliferation of T cells against SEB was profoundly depressed in B6 but not in fos mice. Second, the keyhole limpet hemocyanin-specific CD4 T(h)1 cell clone produced decreasing amounts of IL-2 in response to increasing amounts of concanavalin A (Con A) in vitro, whereas the decrease was less significant in the T(h)1 clones stably transfected with c-fos gene. Electrophoretic mobility shift assay with nuclear protein from the transformants showed that overexpression of the c-fos gene compensated the amounts of AP-1 in the nuclei of Con A-treated T(h)1 clones. Thus, increased c-Fos/AP-1 confers resistance against anergy induction on antigen-specific T cells. 相似文献