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31.
目的探讨脑肿瘤干细胞(BTSCs)体外分化过程中的回逆现象,为研究其分化抑制机制奠定基础。方法利用CD133免疫磁珠筛选系统,从肿瘤组织中分离获得的CD133^+细胞(BTSCs)分成4组进行培养:(1)含10%胎牛血清(FCS);(2)10%FCS+丙戊酸钠注射液(VPA);(3)无FCS+生长因子;(4)无FCS+生长因子+VPA。取不同时间点上的细胞,相差显微镜观察其形态变化:流式细胞术检测与分化相关的标志物、细胞周期和DNA倍体变化;利用免疫激光共聚焦分析与分化相关标志物的共表达情况。结果无FCS条件下培养的BTSCs呈悬浮球状生长,高表达CD133和巢蛋白(nestin),不表达胶质纤维酸性蛋白(GFAP)和β-微管蛋白Ⅲ(β-TubulinⅢ)。G0/G1期细胞占大多数,G2/M期细胞接近0%,DNA都是异倍体,对VPA反应不敏感。含FCS培养的原本悬浮的细胞约4h开始贴壁。均呈圆形。此后逐渐向多形性分化,至7d时分化的细胞部分又返回至圆形。至10d-21d时,有的还能重新恢复球形,并呈悬浮生长。培养3d、7d、10d和21d时,CD133、nestin阳性细胞数先降后升,GFAP^+和β-TubulinⅢ^+细胞数始终处于较低水平。含FCS培养液中加入VPA。细胞形态上未见上述的回逆现象,CD133和nestin表达的先降后升现象消失,GFAP和β-TubulinⅢ在第7天以后表达明显升高,但极大部分细胞共表达nestin。而神经干细胞(NSCs)在含FCS培养至10d时,即以GFAP和β-TubulinⅢ表达为主,未见CD133^+细胞。此外,含血清培养时BTSCs仍以异倍体为主。含少量的G2/M期细胞,加VPA诱导后细胞周期和DNA倍体变化不明显。结论BTSCs在含血清条件下培养出现的多向分化表型不稳定,时有去分化所导致的回逆。加入诱导分化剂VPA培养,虽然能阻止回逆现象出现,并有代表星形胶质细胞和神经元标志物表达上升.但因其共表达nestin而仍属于未完全分化细胞,表明BTSCs分化始终处于受抑状态。 相似文献
32.
预移植在胚胎移植中的意义 总被引:2,自引:0,他引:2
目的 :评价预移植在胚胎移植中的作用。 方法 :在超声波引导下胚胎移植 114个周期 ,其中 10 1个周期进行预移植。比较预移植与未预移植周期临床妊娠率和胚胎种植率 ;按预移植与实际胚胎放置深度差值分组 ,并比较两组妊娠率和胚胎种植率。 结果 :预移植周期与未预移植周期临床妊娠率和种植率统计学差异无显著性(5 9.4 1%和 6 1.5 4 % ,35 .81%和 31.4 3% ,P均 >0 .0 5 ) ;按预移植与实际胚胎放置深度差值分组后 ,两组妊娠率和种植率统计学差异也无显著性 (6 1.5 4 %和 5 8.6 7% ,4 0 .79%和 34.0 9% ,P均 >0 .0 5 )。 结论 :在胚胎移植技术中 ,预移植不能准确指引胚胎移植深度 相似文献
33.
Possible role of IL-2 deficiency for hypogammaglobulinaemia in patients with common variable immunodeficiency. 下载免费PDF全文
J A Rump A Jahreis M Schlesier R Drger I Melchers H H Peter 《Clinical and experimental immunology》1992,89(2):204-210
Common variable immunodeficiency (CVID) patients are unable to produce specific immunoglobulins after antigen contact in vivo. The aim of this study was to investigate whether in some cases of CVID a decreased de novo synthesis of IL-2 might be the cause of immunodeficiency and whether this deficiency can be corrected by IL-2 supplementation in vitro. Mononuclear cells from 17 CVID patients and from 10 healthy controls were cultured with monoclonal anti-CD3 antibody OKT3, pokeweed mitogen (PWM) or tetanus toxoid (TT) to stimulate IL-2 synthesis. In parallel, in vitro IgG and IgM synthesis was stimulated with Staphylococcus aureus Cowan I (SAC), PWM or TT in the presence or absence of IL-2. While lymphocytes of 11 out of 17 patients produced low to normal amounts of IL-2 upon stimulation with anti-CD3, only three patients showed low IL-2 production in response to PWM and five in response to TT. Regarding immunoglobulin synthesis in vitro, five patients completely failed to produce IgM or IgG upon stimulation with PWM, SAC or TT irrespective of the addition of IL-2. By contrast, four patients did not show any defect in vitro and synthesized normal amounts of IgM and IgG with any of the three stimuli. Finally, eight patients could be reconstituted for PWM-, SAC- and TT-induced IgM and/or IgG synthesis in vitro, by adding IL-2 to the culture system. This enhancing effect of IL-2 could be blocked by adding anti-IL-2 receptor antibodies to the cultures. Our findings indicate that a defective IL-2 synthesis after antigen stimulation may be one reason for the impaired immunoglobulin production in some cases of CVID. 相似文献
34.
人乳头瘤病毒(HPV)的16,18,31,33型等与宫颈癌的发病有关,其中HPV16与宫颈癌关系密切。为进一步研究HPV16的致癌性,我们用克隆的HPV16 DNA(2μg/10~5细胞)转染体外培养的人胚肺细胞,并进行了细胞存活时间、血清依赖性、着壁依赖性、间接免疫酶检测、HPV16 DNA、同源序列检测、染色体核型等生物学的研究。结果表明,转染细胞存活时间延长、在软琼脂培养基中形成集落、HPV16特异抗原得以表达、HPV16 DNA的同源序列存在于细胞中。表明本实验用HPV16DNA转染的人胚肺细胞具备转化细胞的某些特征,HPV16有使人胚肺细胞转化的作用。 相似文献
35.
Estil Y. Strawn Jr. MD Miles J. Novy MD Kenneth A. Burry MD Cynthia L. Bethea PhD 《American journal of obstetrics and gynecology》1995,172(6):1837-1844
Objective: Our purpose was to determine whether insulin-like growth factors I and II preferentially stimulate uterine leiomyoma cells versus myometrial cells in monolayer culture.Study design: Leiomyomas and normal myometrium were obtained at hysterectomy from five premenopausal women. Specimens were enzymatically digested for use in primary monolayer cell cultures. By use of serum-free media, insulin-like growth factor I or II was added in 1, 10, and 100 ng/ml concentrations to both cell types with the patient serving as her own control. Cell number, prolactin production, and proliferative index values were measured on day 15 of cell culture.Results: Significant increases in cell number were found in the leiomyoma cultures (p < 0.05) treated with 10 and 100 ng/ml insulin-like growth factors I but not with insulin-like growth factos II. Neither factor exerted a stimulatory effect on myometrial cells.Conclusion: Insulin-like growth factor sI preferentially stimulates leiomyoma cells in monolayer culture. These results suggest an autocrine-paracine role in vivo for this factor in conjuction with gonadal steroids in promoting leiomyoma growth. 相似文献
36.
Mark A. Hutchinson Cynthia L. Darlington Paul F. Smith 《Pharmacology, biochemistry, and behavior》1995,50(4):665-669
Guinea pigs received a 2 mg/kg IP injection of diazepam, or an equivalent volume of vehicle, daily for 28–60 days. To determine whether tolerance developed to the ataxic effects of diazepam on the righting reflex, daily righting reflex latency (RRL) measurements were made before and 20, 30, and 40 min following the diazepam or vehicle injection for 28 days. Analyses of the RRLs for individual animals indicated that a significant decrease in RRL over time (indicating tolerance) occurred in only one out of nine animals receiving diazepam and in none of the vehicle animals. Medial vestibular nucleus (MVN) neurons in brain stem slices from animals receiving chronic diazepam treatment had a significantly higher average firing rate than those from vehicle controls. These results suggest that: a) long-term treatment with single 2 mg/kg daily IP injections of diazepam does not result in tolerance to diazepam's ataxic effects on the righting reflex in the majority of animals; b) this form of diazepam treatment may, nonetheless, induce a hyperactivity of brain stem MVN neurons that may be consistent with the occurrence of a withdrawal syndrome. 相似文献
37.
The in-vitro oestradiol (E2) and progesterone (P) production by corpora lutea (CL) obtained at sterilization from 30 untreated women and 43 women treated with norethisterone (NET) 300 micrograms daily was measured. The CL were obtained at different stages of the luteal phase in the untreated women [luteinizing hormone (LH) 0 to +3, n = 7; LH +4 to +7, n = 7; LH +8 to +11, n = 9; LH +12 to menses, n = 7] and on days LH +8 to +11 or cycle days 22 to 26 in the NET-treated women. In the treated women, four types of ovarian reaction were identified. Four women showed ovarian reaction Type A (completely inhibited ovarian activity), 14 women Type B (marked follicular activity, but no luteal function), 12 women Type C (normal follicular activity, followed by insufficient luteal function) and 13 women Type D (apparently normal follicular and luteal activity). The CL were incubated in Eagle's medium with and without stimulation by human chorionic gonadotrophin (HCG) for 2 and 4 h. In the untreated women, P and E2 production increased significantly with both incubation time and stimulation by HCG throughout the luteal phase, except in the late luteal phase (LH +12 to menses) where P increased (P less than 0.01) only after 4 h stimulation by HCG. The maximal production of P was found after 4 h incubation with HCG stimulation of CL tissue in the early-mid luteal phase (LH +4 to +7).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
38.
39.
作者对核糖体现有的制备方法进行了部分改进,从黄疸出血群赖型017株钩体中成功地制备了核糖体提取物。该提取物经SPA-ELISA 证实具有免疫原性,对40只受试豚鼠的保护试验结果表明,核糖体提取物对同型毒株的攻击具有明显的保护作用;结果还证明核糖体提取物能诱导机体的体液免疫反应。 相似文献
40.
Hydroxocobalamin is a rapid and powerful antidote in acute cyanide poisoning. The effects of hydroxocobalamin (0.1, 0.3, and 1 mM) on intrinsic myocardial contractility were studied on isolated rat cardiac papillary muscles (n=10). Whatever the concentration, hydroxocobalamin did not modify the active isometric force and a slight increase in maximum unloaded shortening velocity was noted at 1 mM. Only 0.3 mM significantly impaired contraction-relaxation coupling under low load, suggesting a slight decrease in sarcoplasmic reticulum function. No changes in contraction relaxation coupling under heavy load were noted, suggesting the lack of modification of myofilament calcium sensitivity. These results suggest that hydroxocobalamin does not induce noticeable changes in intrinsic myocardial contractility. An indirect mechanism might be involved in the previously reported decrease in cardiac function at supratherapeutic concentrations of hydroxocobalamin. 相似文献