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1.
目的:为探索加热治疗胶质瘤的机理,本文对加热引起恶性胶质瘤细胞的多重生物学效应做了研究。方法:用M.T.T.法测定胶质瘤细胞存活率;用Ki-67抗增殖细胞核抗原单克隆抗体,通过免疫组织化学ABC染色分析胶质瘤细胞的增殖活性;用划痕染料示踪技术观察胶质瘤细胞的细胞间隙连接通讯。结果:加热能抑制胶质瘤的存活率和增殖活性,并能促进细胞间隙连接通讯的增强。在41℃~45℃温度范围内,随着温度的升高,这些作用越明显。结论:恶性胶质瘤对加热有良好的敏感性,为加热治疗胶质瘤提供了有力的依据。 相似文献
2.
连接蛋白基因是一个抑癌基因家族 ,其编码蛋白质是介导细胞间通讯的间隙连接的基本结构和功能单位。成人脑组织主要表达Cx4 3和Cx32。脑胶质瘤中Cx4 3基因表达水平可下降或缺失。转染Cx4 3cDNA于胶质瘤细胞后 ,其恶性表型逆转、生长速度减慢、致瘤性降低。 相似文献
3.
近几年来,微波加热技术治疗脑瘤已引起临床医师的重视,并显示了广阔的应用前景。1 微波加热的理论基础 一般认为高热是指人的体温超过40℃而言。它可引起机体的生化代谢和病理形态学改变,从而导致细胞死亡。研究表明高热引起机体内细胞浆膜及细胞骨架的变化,可使细胞Ca~( )浓度升高,偶见K~ 、Cl~-、Na~ 和H~ 等浓度的改变,Ca~( )与细胞的死亡直接相关。G_1和S期细胞加热后,细胞膜损伤严重,染色体发生畸变,后者形成多核巨细胞,分裂后死亡。高热时可直接影响细胞核及其核仁的改变,继发于膜结构及细胞骨架的损伤,多聚酶活性的丧失,DNA合成的抑制以及染色体畸变等。在同样条件下,肿瘤组织比周围正常组织病理损害严重。肿瘤细 相似文献
4.
应用DNA凝胶电冰、电镜观察和流式细胞仪分析,对加热诱导G422胶质瘤程序性细胞死亡的作用进行了研究。结果表明,对脑荷G422胶质瘤鼠加热处理,可以诱导胶质瘤程序性细胞死亡,并与加热的剂量(温度×时间)和加热后恢复的时间有关。45℃30分钟的加热剂量诱导作用最强,高峰时间在加热后2~12小时。文中对加热诱导胶质瘤程序性细胞死亡的意义作了讨论。 相似文献
5.
目的探讨靶向乙酰肝素酶(HPSE)的小于扰RNA(siRNA)对人脑胶质瘤细胞株U251恶性生物学行为的影响。方法针对HPSEmRNA序列设计并合成3条siRNA.利用脂质体Lipofectemine2000作为载体将siRNA转染U251细胞,采用反转录聚合酶链反应(RT-PCRl和免疫细胞化学方法分别检测转染前后U251细胞中HPSE基因mRNA及蛋白的表达水平,同时利用MTT法和Mitragel法检测细胞增殖率和侵袭力的变化。结果转染靶向HPSE基因siRNA后的U251细胞HPSE基因mRNA及蛋白表达水平降低,同时细胞增殖率和侵袭力均受到抑制。结论靶向HPSE基因的siRNA能通过抑制U251细胞中HPSE基因的表达降低U251细胞恶性生物学行为。 相似文献
7.
目的探讨Survivin拮抗肽对人胶质瘤U251细胞体外增殖的抑制作用及细胞周期的影响。方法将U251细胞与不同浓度的Survivin拮抗肽进行体外培养,采用四甲基偶氮唑蓝法测定不同浓度的Survivin拮抗肽对U251细胞的生长抑制率;采用流式细胞仪分析细胞周期与细胞凋亡。结果浓度为5、10、20ug/ml的Survivin拮抗肽均能抑制U251细胞的生长,且抑制率与Survivin拮抗肽浓度及作用时间成正比(P〈0.01)。20ug/ml Survivin拮抗肽作用U251细胞72h,抑制率达63.33%。流式细胞仪结果显示,终浓度为5、10、20ug/ml Survivin拮抗肽亦能促进U251细胞凋亡,且随作用浓度增大及作用时间延长凋亡率明显上升(P〈0.01);20ug/ml Survivin拈抗肽作用U251细胞72h,凋亡率为31.29%。不同浓度的Survivin拮抗肽作用U251细胞72h,随作用浓度增大,G2/M期细胞构成比明显上升(P〈0.01)。结论Survivin拮抗肽对U251细胞增殖具有抑制作用和促进凋亡,其抗胶质瘤细胞增殖作用机制可能为诱导肿瘤细胞凋亡,调控肿瘤细胞周期。 相似文献
8.
目的建立人脑胶质瘤细胞体外分离培养体系,观察不同病理分级胶质瘤细胞的基本生物学特性,探讨病理分级与胶质瘤细胞生物学特性之间的关系。方法采集手术切除新鲜胶质瘤标本,进行体外分离培养,运用免疫细胞化学染色、流式细胞仪和染色体核型分析等技术对胶质瘤细胞形态学、生长特性和染色体核型变化情况进行观察和比较分析。结果①原代培养胶质瘤细胞主要呈现圆形、星形和梭形三种细胞形态。②星形细胞瘤细胞生长速度与病理分级相关,恶性程度越高,细胞增殖越快。③染色体核型分析结果可见胶质瘤细胞存在染色体数目与结构异常。结论星形胶质瘤细胞的分离培养试验提示:星形细胞瘤细胞生长速度与病理分级呈正相关,恶性程度越高,增殖速度越快。 相似文献
9.
目的研究雄激素受体(androgen receptor,AR)抑制剂(flutamide)对人胶质瘤细胞增殖、凋亡、侵袭的影响。方法采用不同浓度的flutamide(低浓度1.0×10~(-8)、中浓度1.0×10~(-7)、高浓度1.0×10~(-6)mol/L)作用于胶质瘤细胞系U251,Real Time-PCR和Western Blot检测AR m RNA及AR蛋白的表达情况;Cell Counting Kit-8法测定flutamide对胶质瘤细胞增殖的影响;Annexin V-7AAD/PE双染检测flutamide诱导胶质瘤细胞凋亡的作用;Transwell测定flutamide对胶质瘤细胞侵袭能力的改变。结果在体外胶质瘤细胞的增殖、侵袭能力能被AR抑制剂(flutamide)显著抑制且凋亡增加,与药物浓度正相关。结论 AR抑制剂(flutamide)能明显抑制胶质瘤细胞的增殖与侵袭,并且诱导细胞凋亡,AR可能是引起胶质瘤发生、发展的危险因素。 相似文献
10.
目的观察苯乙酸(PA)对胶质瘤C6细胞凋亡和细胞内游离Ca2 浓度的影响,探讨其作用机制。方法体外培养胶质瘤C6细胞,PA诱导分化后,用透射电镜和Annexin V/PI标记流式细胞仪检测细胞凋亡,Fluo-3/AM探针激光共聚焦显微镜检测细胞内游离Ca2 浓度的变化。结果电镜观察到凋亡细胞,PA对C6细胞早期凋亡率无影响,主要增加晚期凋亡率,随PA浓度的增加而增加。PA能明显增加细胞内游离Ca2 浓度,并且随药物浓度的增加而增加。结论PA能诱导C6细胞凋亡,呈剂量依赖性,PA诱导C6细胞凋亡的机制可能与增加细胞内游离Ca2 浓度有关。 相似文献
11.
This study investigated the effects of 30% oxygen administration on visuospatial cognitive ability using time course data analysis of fMRI. A visuospatial task was presented while brain images were scanned by a 3T MRI system. The results showed that there was an improvement in performance and also increased BOLD intensity in the parietal lobe in the higher oxygen condition. There was positive relation between behavior performance and BOLD intensity in the right parietal lobe. This result supports the conclusion that the increase in the cognitive processing ability due to highly concentrated oxygen can be explained by the increase in the BOLD intensity. 相似文献
12.
In this study, we investigated the effect of pergolide, a dopaminergic agonist, on cognitive ability in young and middle-aged rats using the Morris Water Maze (MWM). Pergolide 0.5/mg/day IP was administered to young and middle-aged rats, whereas only vehicle was given to their age-matched controls. During the acquisition period of 6 days, young rats showed normal escape latency pattern, which was not affected by pergolide. Middle-aged rats, however, showed poor escape latency pattern, and this poor pattern was also not affected by pergolide. On the 7th day, pergolide decreased retention time of young rats compared to control values. Middle-aged rats also showed reduced retention time. In contrast to the findings of young rats, retention time was not affected by pergolide in middle-aged rats. We concluded that pergolide does not alter escape latency at any age. It has a negative effect on retention time of young rats, whereas it has no effect on middle-aged ones. 相似文献
13.
研究胎脑提取液对脊髓损伤修复的影响。用SD大鼠40 只,过半切除长约05 cm 的左下胸段(T8,T9)脊髓,肌基膜管(MBL)桥接脊髓缺损。局部用药组将MBL浸泡于胎脑提取液(EFB)中,全身用药组腹腔注射EFB,生理盐水(NS)作对照。实验组动物行为学测试指标和斜板试验IP分数均明显优于对照组;实验组术后6 周可测到SEP波形,而对照组未测到;实验组MBL与脊髓融合,MBL内有髓神经纤维髓鞘较厚,轴突直径较粗,腰部脊神经节细胞结构完整,均优于对照组;图像分析显示实验组MBL内有髓神经纤维数、轴突直径和脊神经节细胞数均优于对照组。局部和全身应用EFB对脊髓损伤修复均有明显促进作用 相似文献
14.
Yangkyuk-Sanhwa-Tang (YST) has been used for the Soyangin cerebral infarction (CI) patients according to Sasang constitutional philosophy. This study investigated the effect of YST on production of various cytokines using peripheral blood mononuclear cells (PBMCs) from the Soyangin CI patients group. The amount of interleukin (IL)-1α, IL-1β, IL-6, IL-8, and tumor necrosis factor-α increased in the lipopolysaccharide (LPS)-treated cells compared with unstimulated-cells. YST inhibited IL-1α, IL-1β, and IL-8 production in PBMCs stimulated with LPS. These data suggest that YST has a regulatory effect on cytokine production, which might explain its beneficial effect in the treatment of Soyangin CI patients. 相似文献
15.
Although hormone replacement therapy (HRT) appears to protect women from ischaemic heart disease (IHD), its use is associated with increased factor clotting activity (VIIc), an independent risk factor for IHD. The nature of this factor VII rise was therefore examined in a cross-sectional study of 279 women aged between 40 and 65 years. Ninety-four were pre-menopausal, 44 were post-menopausal and taking HRT, whilst 141 were post-menopausal non-users. For those women on oestrogen-only HRT, the mean factor VIIc was 144%, compared to 130% for post-menopausal non-users, and 116% for those on combined HRT. These differences were significant (p=0.01). Oestrogen-only users also had significantly higher mean levels of factor VIIa (3.3ng/ml) compared to non-users (2.2ng/ml) and those on oestrogen-progestogen HRT (2.2ng/ml − p = 0.015). In contrast for factor VII antigen the mean values of the three groups were similar. Analysis of the age-regression slopes showed a significant age-related rise in factor VIIc of 1.2% per annum (p < 0.01) for post-menopausal non-users. There was a similar increase in factor VII antigen (2.1%) but no rise in factor VIIa. For all HRT users there was no change with age for any of the factor VII measures. Thus the age-related rise in factor VIIc appears to be due to an increase in factor VII zymogen alone, and taking HRT seems to abolish such a rise. In contrast, the increased factor VIIc seen with oestrogen-only HRT appears to be secondary to factor VII activation. © 1997 Elsevier Science Ltd 相似文献
16.
We analyzed the in vitro effects of sorbitol and fructose on platelet function. Sorbitol and fructose increased platelet aggregation induced with adenosine diphosphate (ADP) or collagen in whole blood, but had no effect in platelet-rich plasma. The concentration that increased basal aggregation by 50% with ADP as the inducer was 12.89 ± 1.55 mmol/L for fructose, and 18.99 ± 2.01 mmol/L for sorbitol. When collagen was the inducer, these concentrations were 15.02 ± 0.98 mmol/L for fructose, and 12.94 ± 1.57 mmol/L for sorbitol. Both sugars increased, in a concentration-dependent way, the proaggregatory effect of erythrocytes, and erythrocyte uptake of adenosine. Time to uptake of 50% adenosine was 2.1 ± 0.3 min in control samples, 0.14 ± 0.01 min in the presence of fructose, and 0.23 ± 0.03 min with sorbitol. Both sugars reduced vascular prostacyclin synthesis, with 50% inhibitory concentrations of 26.48 ± 1.97 mmol/L for fructose, and 39.53 ± 2.81 mmol/L for sorbitol. Both sugars also increased arterial lipid peroxidation by 30% (sorbitol) and 23% (fructose). We conclude that these two sugars enhance platelet function and disrupt the thromboxane/prostacyclin ratio. © 1997 Elsevier Science Ltd 相似文献
17.
为研究糖皮质激素对原代培养大鼠肾上腺嗜铬细胞(AMCC)受激动所致儿茶酚胺的快速作用,用HPLC-ED方法检测了乙酰胆碱(10-5mol/L)、烟碱(10-5mol/L)、毒蕈碱(10-5mol/L)及55mmol/L的KCl在20min内所引起的儿茶酚胺量.地塞米松(Dex,10-4mol/L及10-5mol/L)及皮质酮(10-5mol/L)可以抑制AMCC的儿茶酚胺分泌;10-7mol/L的17β-雌二醇不能抑制,但10-5mol/L的可以抑制其分泌;醛固酮、雄烯二酮及胆固醇无抑制效应。为了揭示与分泌有关的细胞内变化,用SPex检测系统检测了细胞内钙([Ca2 ])的含量。发现地塞米松及皮质酮有抑制因乙酰胆碱、烟碱、毒蕈碱及高K 所引起的[Ca2 ]升高的作用,而17β-雌二醇、孕酮、醛固酮及雄烯二酮则无此作用。10-4mol/L的RU38486可部分阻断皮质酮的抑制效应,当细胞外无钙时毒蕈也能引起[Ca2 ].升高,此效应也可被皮质酮所阻断。上述结果表明:糖度质激素抑制AMCC的激动性儿茶酚胺分泌是非基因组的,此作用经过抑制其细胞内钙升高而实现,并提示有膜受体的参与。 相似文献
18.
Systemic kainic acid (KA) administration to rats triggers wet dog shakes (WDS) followed by epileptic seizures. Although WDS are often associated with the occurrence of seizures, we have recently shown that following nitric oxide (NO) synthesis inhibition, the number of WDS decreased; subsequently the onset of seizure activity was shortened, and the number of convulsions was increased. Somatostatin (SS), whose release appears to be controlled by NO, inhibits seizure activity. There are sex differences in seizure susceptibility as well as in SS and NO activities in brain. The present study was undertaken to assess the effect of octreotide (OC), a stable SS analogue, on KA-induced WDS and seizures in rats, with emphasis on possible sex differences. WDS and seizures were induced by KA in male and female (proestrus) Sprague Dawley rats; OC or saline was injected 30 min before KA and the behavior was monitored for 120 min after KA. Octreotide increased the number of WDS and decreased the number of convulsions; this effect was more pronounced in males. Onset of KA-induced seizure ac tivity was earlier in females than males; however, there was no effect of OC on seizure latency. Seizure activity started after the termination of WDS. These results show OC has opposite effects on WDS and convulsions, in that it stimulates the former and inhibits the latter. These results support our previous findings that WDS and seizure activity involve separate mechanisms and suggest that WDS may have an inhibitory effect on limbic seizures. 相似文献
19.
采用行为测试和亚微结构定量分析相结合的方法,研究了Mg2+对小鼠分辨学习和记忆巩固的影响,同时测定了海马CA3区及大脑皮层突触界面结构参数的变化。实验结果表明:慢性给予Mg2+后,血浆及海马内Mg2+含量有一定程度的升高,小鼠分辨学习能力显著下降,记忆巩固受到破坏,并且海马CA3区及大脑皮层的突触后致密物质(post—synapticdensity,PSD)显著变薄,同时,皮层突触活性区长度亦显著缩短。以上结果提示,脑内Mg2+水平过高造成的学习记忆过程损伤可能与其改变PSD厚度和突触活性区长度密切相关。 相似文献
20.
One major pathogenesis in degenerative disorders of the central nervous system (CNS), including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and ischemia, is the oxidative stress induced by reactive oxygen species (ROS). The present study investigated the protective effect of colloidal silver, which is widely marketed as a dietary supplement for diseases like diabetes, AIDS, cancer, and various infections, upon the oxidative brain damage induced by H 2O 2 or naphthazarin treatment. LDH release from primary cultured astrocytes was enhanced by naphthazarin treatment, and this elevation of the LDH concentration in medium was blocked by colloidal silver treatment. However, hydrogen peroxide was little affected by the colloidal silver. Fluorescence of DCF (peroxides) increased in astrocytes incubated with hydrogen peroxide or naphthazarin compared to the control. When exposed to naphthazarin-induced cells, ROS formation appeared to be reduced by colloidal silver. However, intracellular ROS formation in hydrogen peroxide–treated cells slightly reduced by colloidal silver. These results suggest that colloidal silver has a protective activity against the oxidative stress induced by naphthazarin, but not by hydrogen peroxide. 相似文献
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