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1.
以巯基试剂5,5＇—二硫对硝基苯甲酸(DTNB)为试剂,分光光度法研究了人血红细胞膜蛋白巯基与顺—二氯二氨合铂(Ⅱ)(顺铂,CDDP)、反—二氯二氨合铂(Ⅱ)(反铂,TDDP),顺—二氨二水合铂(Ⅱ)(水解铂,CAAP)、顺—二碘二氨合铂(Ⅱ)(碘铂)、顺—二氨—1,1—环丁二甲酸根合铂(Ⅱ)(卡铂,CBDCA)的相互作用的速度,其结合能力为:碘铂>反铂>顺铂>水解铂>卡铂同时探讨了DTNB的光敏特性。  相似文献   

2.
目的:研究凋亡调控相关蛋白来了解顺铂耐药成因,同时考察乙烷硒啉(Ethaselen)在K562耐药细胞中逆转顺铂耐药的作用,并初步探讨其作用机制。创新点:首次研究乙烷硒啉在逆转顺铂耐药中的作用,且此作用与乙烷硒啉诱导细胞凋亡相关。方法:通过长时间脉冲诱导得到顺铂耐药K562细胞,并观察耐药细胞形态及倍增时间。采用MTT法考察乙烷硒啉、顺铂及其联用组在不同细胞株间的生长抑制作用。流式细胞术分析细胞凋亡情况以及细胞内活性氧(ROS)水平。最后,通过蛋白质免疫印迹(Western blot)考察凋亡调控相关蛋白水平的变化。结论:脉冲诱导得到的K562耐药细胞对顺铂的耐受性是原K562细胞的5.34倍。形态学观察发现,耐药细胞体积增大,粘附性进一步降低。乙烷硒啉与顺铂联用表现出协同效应。当加入少量的乙烷硒啉(顺铂与乙烷硒啉的摩尔比率为10:1),顺铂作用K562耐药细胞的半抑制浓度(IC50)值可以减少21倍。流式细胞术及Western blot表明,乙烷硒啉能够诱导耐药细胞凋亡。其逆转顺铂耐药主要是通过调控Bcl-2及Bax蛋白比例以及通过提高细胞内活性氧水平引起线粒体通透转运孔道(PTP)蛋白孔道的形成来促使释放细胞色素c,进而引起Caspase凋亡途径。  相似文献   

3.
探索1,6-二磷酸果糖(FDP)在分子水平对蹦床运动员疲劳后红细胞(RBC)能量代谢的影响规律,为运动性疲劳的恢复提供实验研究依据。FDP 800mmol/L和0mmol/L分别孵育疲劳后红细胞,分别用细胞化学方法、比色法、高效液相色谱法检测细胞色素氧化酶活力,2,3-二磷酸甘油酸(2,3-DPG)水平,三磷酸腺苷(ATP)、二磷酸腺苷(ADP)、一磷酸腺苷(AMP)含量并计算能荷。FDP处理后红细胞ATP、能荷、细胞色素氧化酶活力和2,3-DPG水平显著增加,ADP和AMP含量显著下降。FDP能够通过增加细胞色素氧化酶活力,提高2,3-DPG水平来改善疲劳红细胞能量供应,缓解运动性疲劳。  相似文献   

4.
顺铂是目前治疗癌症最有效的药物之一,测定细胞内顺铂的含量对于了解细胞摄取顺铂和顺铂发挥药效有重要作用．本研究通过MTT法检测了顺铂杀伤K562细胞的有效浓度,建立并利用高效液相色谱法（HPLC）检测了K562细胞对顺铂的摄入．结果表明K562细胞经10μg/mL顺铂处理12h后,细胞活性显著下降;细胞外有36．75％顺铂进入胞内．实验数据显示,顺铂对K562细胞的杀伤与其在胞内的累积相关．  相似文献   

5.
建立了检测1640培养液中顺铂含量的火焰原子吸收光谱实验方法,并用该方法来检测人白血病细胞K562经10μg/mL顺铂孵育8 h后,细胞外液的顺铂含量.具体方法为:将含有顺铂的培养液加热干燥后用含有释放剂的无机酸溶剂溶解,火焰原子吸收光谱法测定铂的含量.对无机酸和释放剂进行了筛选,确定了最佳测定条件并检测了上述实验条件下细胞外液中的顺铂含量.结果显示,含顺铂的培养液或细胞外液加热干燥后,可用体积分数为1%HNO3溶液完全溶解,在溶解过程中加入质量分数为1%的La(NO3)3,可使铂成分获得良好的释放效果.K562细胞经10μg/mL顺铂孵育8 h可致细胞活性显著下降(P0.05),此时约6.2%顺铂进入胞内.与传统顺铂检测方法相比,文中的制样方法可使样品不经灰化即可有效检测肿瘤细胞对顺铂的吸收量.  相似文献   

6.
目的 :探讨顺铂对耳蜗毒性的影响。方法 :将豚鼠 12只随机分成顺铂组、对照组 ,每组 6只。顺铂组连续 5d腹腔注射顺铂 ,2ml·kg- 1·d- 1;对照组连续 5d腹腔注射生理盐水 ,2ml·kg- 1·d- 1。两组豚鼠均于实验结束后测耳蜗血流、耳蜗电图 ,断头 ,取耳蜗 ,用不同方法染色固定 ,铺片及电镜观察。结果 :顺铂组动物在给药后体重减轻 ,耳廓反射减退 ,耳蜗血流下降 ,阈值提高 ,毛细胞大片缺失 ,两组比较 ,差异有显著性 (P <0 .0 1)。顺铂组血管纹较对照组血管纹明显扩张 ,红细胞聚集。扫描电镜下观察 ,顺铂组的绝大部分内、外毛细胞的纤毛散乱 ,倒伏 ,甚至缺失 ;透射电镜下观察 ,顺铂组血管纹线粒体水肿变性。结论 :顺铂对耳蜗有损坏作用。  相似文献   

7.
癌是一个向人体发动战争的狡猾敌人 ,它在不知不觉中潜伏于人体长达数年之久 ,最后致人于死地。它是由于控制细胞繁殖的基因发生变异 ,使细胞过量繁殖而生成肿瘤。幸运的是科学家已经发现了许多能向癌细胞进行反击的抗癌药物。顺铂就是其中一个。顺铂 ,即顺二氯二胺铂 [cis-Pt( NH3 ) 2 Cl2 ;cisplatin;cis-dichlorodiamm mine platinum( ) ]是目前临床常用的抗癌药物之一 ,是现有抗癌药物中分子结构最简单的一个。它是由铂 ( )与两个 Cl-和两个氨分子形成的配合物。在这种配合物中有顺式和反式两种 ,其中顺式 (顺铂 )有高的抗癌活性 ,…  相似文献   

8.
一、求函数的定义域的试题例1 已知f(x+1)的定义域是[-2,3),求,f(1/x+2)的定义域.解∵f(x+1)的定义域为[-2,3),即-2≤x<3, ∴-1≤x+1<4 ,∴-1≤1/x+2<4.∴x≤-1/3或x>1/2故f(1/x+2)的定义域为(-∞,-1/3]∪(1/2,+∞).二、确定取值范围的试题例2如果函数f(x)的定义域为{x|x>0},且,f(x)为增函数,f(x·y)=f(x)+f(y).  相似文献   

9.
1 以过氧化钠为主体的知识总结 问题1:标出过氧化钠与水、二氧化碳反应的电子转移方向和数目. 解析:(失2×e-) 2Na2O2+4H2O=4NaOH+O2↑+2H2O(得2×e-) (失2e-)2Na2O2+2CO2=2Na2CO3+O2(得2×e-) 问题2:由2Na2O2+2CO2=2Na2CO3+ O2知,2Na2O2+2SO2=2Na2SO3+O2对吗?  相似文献   

10.
目的:通过观察大蒜素对体外培养的人上皮性卵巢癌耐顺铂细胞株(SKOV-3/DDP)的超微结构的影响,以期寻找对耐顺铂治疗的上皮性卵巢癌患者的有效治疗药物。方法:细胞培养:体外培养人上皮性卵巢癌耐顺铂细胞株SKOV-3/DDP,细胞生长至对数生长期后,调整细胞密度为5×l04/ml置于200ml的培养瓶中培养。用透射电子显微镜观察大蒜素作用后SKOV-3/DDP细胞的超微结构:大蒜素组用含25μg/ml大蒜素的培养液培养SKOV-3/DDP细胞,空白对照组用不含药的培养液培养SKOV-3/DDP细胞,两组作用24小时后收集细胞,通过透射电子显微镜观察SKOV-3/DDP的超微结构。结果:大蒜素对SKOV-3/DDP细胞超微结构的影响:透射电子显微镜观察未加药物培养的SKOV-3/DDP细胞呈椭圆形,细胞核为卵圆形,未出现凋亡细胞,经过大蒜素作用后的SKOV-3/DDP细胞则出现明显的超微结构改变并具有典型凋亡细胞特征:细胞核固缩,核膜皱缩,胞浆浓缩并出现大小不等的空泡,染色质浓聚,形成凋亡小体。结论:大蒜素可诱导SKOV-3/DDP细胞呈凋亡改变。大蒜素可诱导SKOV-3/DDP细胞凋亡可能是其对人耐顺铂上皮性卵巢癌的抗癌机制之一,为使大蒜素成为治疗耐顺铂上皮性卵巢癌患者的有效药物提供了可靠的体外实验依据。  相似文献   

11.
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12.
Objective: To test the influence of homocysteine on the production and activation of matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of matrix metalloproteinase-2 (TIMP-2) and on cell migration of cultured rat vascular smooth muscle cells (VSMCs). Also, to explore whether rosuvastatin can alter the abnormal secretion and activation of MMP-2 and TIMP-2 and migration of VSMCs induced by homocysteine. Methods: Rat VSMCs were incubated with different concentrations of homocysteine (50–5 000 μmol/L). Western blotting and gelatin zymography were used to investigate the expressions and activities of MMP-2 and TIMP-2 in VSMCs in culture medium when induced with homocysteine for 24, 48, and 72 h. Transwell chambers were employed to test the migratory ability of VSMCs when incubated with homocysteine for 48 h. Different concentrations of rosuvastatin (10−9–10−5 mol/L) were added when VSMCs were induced with 1 000 μmol/L homocysteine. The expressions and activities of MMP-2 and TIMP-2 were examined after incubating for 24, 48, and 72 h, and the migration of VSMCs was also examined after incubating for 48 h. Results: Homocysteine (50–1 000 μmol/L) increased the production and activation of MMP-2 and expression of TIMP-2 in a dose-dependent manner. However, when incubated with 5 000 μmol/L homocysteine, the expression of MMP-2 was up-regulated, but its activity was down-regulated. Increased homocysteine-induced production and activation of MMP-2 were reduced by rosuvastatin in a dose-dependent manner whereas secretion of TIMP-2 was not significantly altered by rosuvastatin. Homocysteine (50–5 000 μmol/L) stimulated the migration of VSMCs in a dose-dependent manner, but this effect was eliminated by rosuvastatin. Conclusions: Homocysteine (50–1 000 μmol/L) significantly increased the production and activation of MMP-2, the expression of TIMP-2, and the migration of VSMCs in a dose-dependent manner. Additional extracellular rosuvastatin can decrease the excessive expression and activation of MMP-2 and abnormal migration of VSMCs induced by homocysteine.  相似文献   

13.
This study aims to elucidate the antiproliferative mechanism of hydroxychavicol(HC).Its effects on cell cycle,apoptosis,and the expression of c-Jun N-terminal kinase(JNK)and P38 mitogen-activated protein kinase(MAPK)in HT-29 colon cancer cells were investigated.HC was isolated from Piper betle leaf(PBL)and verified by high-performance liquid chromatography(HPLC),nuclear magnetic resonance(NMR),and gas chromatography-mass spectrometry(GC-MS).The cytotoxic effects of the standard drug 5-fluorouracil(5-FU),PBL water extract,and HC on HT-29 cells were measured after 24,48,and 72 h of treatment.Cell cycle and apoptosis modulation by 5-FU and HC treatments were investigated up to 30 h.Changes in phosphorylated JNK(pJNK)and P38(pP38)MAPK expression were observed up to 18 h.The half maximal inhibitory concentration(IC50)values of HC(30μg/mL)and PBL water extract(380μg/mL)were achieved at 24 h,whereas the IC50of 5-FU(50μmol/L)was obtained at 72 h.Cell cycle arrest at the G0/G1 phase in HC-treated cells was observed from12 h onwards.Higher apoptotic cell death in HC-treated cells compared to 5-FU-treated cells(P<0.05)was observed.High expression of pJNK and pP38 MAPK was observed at 12 h in HC-treated cells,but not in 5-FU-treated HT-29 cells(P<0.05).It is concluded that HC induces cell cycle arrest and apoptosis of HT-29 cells,with these actions possibly mediated by JNK and P38 MAPK.  相似文献   

14.
Borneol, a monoterpenoid alcohol, is used widely, particularly in combined formulas for preventing and curing cardiovascular and cerebrovascular diseases in traditional Chinese medicine. In order to understand the blood and brain pharmacokinetics after intravenous, intranasal, or oral administration and to investigate the superiority and feasibility of intranasal administration, a simple gas chromatographic (GC) method with flame ionization detection (FID) was developed for the quantification of borneol. Blood samples and brain were collected from mice at 1, 3, 5, 10, 20, 30, 60, 90, and 120 min after intravenous, intranasal, or oral administration of borneol at a dosage of 30.0 mg/kg. Sample preparations were carried out by liquid-liquid extraction with an internal standard solution of octadecane. The pharmacokinetic parameters were calculated by the software of Kinetica. The calibration curves were linear in the range of 0.11–84.24 μg/ml and 0.16–63.18 μg/g for borneol in plasma and brain, respectively. The methodological and extraction recoveries were both in the range of 85%–115%. The intra-day and inter-day variabilities for plasma and brain samples were ≤5.00% relative standard deviation (RSD). The absolute bioavailabilities F of intranasal and oral administrations were 90.68% and 42.99%. The relative brain targeted coefficients Re of intranasal and oral administrations were 68.37% and 38.40%. The GC-FID method developed could be applied to determination and pharmacokinetic study. The borneol from injection was distributed and metabolized fast without absorption process. The borneol from oral administration was distributed more slowly and had the lowest absolute bioavailability. Nasal administration of borneol was quickly absorbed into the blood and brain, was easy to use and had a greater safety than infection, which makes it worthy of further development as an administration route for encephalopathy treatment.  相似文献   

15.
Objective: To evaluate the immunological effects of three types of domestic 10-μg/dose hepatitis B vaccines in adults compared with a foreign vaccine, and to provide scientific evidence in support of adult hepatitis B vaccination. Methods: Adults from five counties (Deqing, Changxing, Nanxun, Wuxing, Anji) in Huzhou City, Shaoxing County and Tongxiang County, Zhejiang Province, China were selected. Blood samples were taken to assess serum HBsAg, anti-HBs, and anti-HBc using a chemiluminescence immunoassay. Adults, aged 16 to 49 years and who were anti-HBs negative at baseline, received hepatitis B immunizations at 0, 1, and 6 months. Anti-HBs levels were assessed one month after the third and final vaccination. Results: A total of 1 872 adults were immunized and the average positive rate was 89.5%. Four types of hepatitis B vaccine were used, including three from Chinese companies (Shenzhen Kangtai, Dalian High-Tech, and North China Pharmaceutical) and one from a UK company (GlaxoSmithKline). Their seroconversion rates were 81.67%, 95.05%, 89.64%, and 86.81%, respectively. There was a significant difference between the anti-HBs positive conversion rates of the four types (P<0.005) but the seroconversion rates among the different vaccines were not significantly different (χ 2=2.123, P=0.145). The average anti-HBs geometric mean titers (GMTs) of non-immune adults immunized with each of the four vaccines were 177.28, 473.23, 246.13, and 332.20 mIU/ml, respectively. There were no statistically significant differences in the GMTs between the three types of domestic vaccine and the foreign vaccine (t=−1.575, P=0.116). Conclusions: Domestic recombinant hepatitis B vaccines can achieve immunization effects comparable to those of a foreign vaccine.  相似文献   

16.
In the present study, we investigated the possible toxicity mechanism of lipopolysaccharide (LPS) extracted from Gram-negative bacteria in Eriocheir sinensis hemocytes. Apoptotic hemocytes and reactive oxygen species (ROS) production induced by the LPS were monitored by the combination of flow cytometry and microscope observation. It was shown that LPS induced serious damage on the DNA and morphological changes in hemocytes, including cell shrinkage, fracture of nucleus membrane, margination, condensation and fragmentation of chromatin, and formation of apoptotic bodies indicating obvious hemocyte apoptosis. As compared with the control group, the apoptotic cell ratio increased to 30.61% and 39.01% after 1-h exposure and 57.72% and 75.01% after 2-h exposure to 1 and 10 μg/ml LPS, respectively (P<0.05). Significant outburst of ROS production was observed in LPS-treated hemocytes with approximately 176.6% of relative dichlorofluorescein mean fluorescence at 1-h exposure, followed by a drastic decline (P<0.05). These results indicated that LPS would induce oxidative stress on hemocytes from E. sinensis and cause ROS burst, DNA damage, and subsequently apoptosis. The process of ROS-mediated apoptosis might be one of the potential toxicity mechanisms of LPS on crustacean hemocytes.  相似文献   

17.
Background and objective: Gonadotropin-releasing hormone (GnRH) plays an important role in the regulation of ovarian function and ovarian cancer cell growth. In this study, we determined whether administration of the GnRH agonist (GnRHa), triporelin, prior to cisplatin treatment affects cisplatin and/or prevents cisplatin-induced ovarian damage. Methods: nu/nu mice were injected with ovarian cancer OVCAR-3 cells intraperitoneally. After two weeks, the mice were treated with saline (control), cisplatin, GnRHa, or cisplatin plus GnRHa for four weeks. At the end of the experimental protocol, blood, tumor, ovary, and uterine tissues were resected for hematoxylin and eosin (H&E) staining, immunohistochemical analyses of Ki67, nuclear factor-κB (NF-κB), and caspase-3, transmission electron microscopy of apoptosis, or enzyme-linked immunosorbent assay (ELISA) analyses of anti-Mullerian hormone (AMH). Results: Cisplatin treatment effectively inhibited tumor growth in mice treated with human ovarian cancer cells; however the treatment also induced considerable toxicity. Immunohistochemical analyses showed that Ki67 expression was reduced in cisplatin-treated mice compared to control (P<0.05), but there was no statistically significant differences between cisplatin-treated mice and cisplatin plus GnRHa-treated mice (P>0.05), while expressions of NF-κB and caspase-3 were reduced and induced, respectively, in cisplatin-treated mice and cisplatin plus GnRHa-treated mice. Apoptosis occurred in the GnRHa, cisplatin, and cisplatin plus GnRHa-treated mice, but not in control mice. Ovaries exposed to GnRHa in both GnRHa mice and cisplatin-treated mice (combination group) had significantly more primordial and growth follicles and serum levels of AMH than those in the control mice and cisplatin-treated mice (P<0.05). Conclusions: Administration of GnRHa to mice significantly decreased the extent of ovarian damage induced by cisplatin, but did not affect the anti-tumor activity of cisplatin.  相似文献   

18.
目的:评价瞬时受体电位通道(TRP通道)TRPV1、TRPA1和TRPM8拮抗剂在小鼠神经源性、持续性和神经病理性疼痛模型中的作用。方法:通过辣椒素实验、异硫氰酸烯丙酯(AITC)实验和福尔马林实验,评估TRP通道拮抗剂在小鼠神经源性疼痛模型中的镇痛作用;通过建立紫杉醇诱导的小鼠神经病理性疼痛模型,对TRP通道拮抗剂的抗痛觉(冷、热、触觉)过敏效应进行评估;通过旋转法实验对小鼠的运动协调性进行评估。结论:TRP通道家族包含了不同的小鼠疼痛模型。TRP通道拮抗剂能减轻神经源性、持续性和神经病理性疼痛,但是其镇痛效果与疼痛模型有关。  相似文献   

19.
A highly sensitive amperometric sulfadiazine sensor fabricated by electrochemical deposition of poly(cobalt tetraaminophthalocyanine) (poly(CoIITAPc)) on the surface of a multi-walled carbon nanotubes-Nafion (MWCNTs-Nafion) modified electrode is described. This electrode showed a very attractive performance by combining the advantages of CoIITAPc, MWCNTs, and Nafion. Compared with the bare glassy carbon electrode (GCE) and the MWCNTs-Nafion modified electrode, the electrocatalytic activity of poly(CoIITAPc)-coated MWCNTs-Nafion GCE generated greatly improved electrochemical detections toward sulfadiazine including low oxidation potential, high current responses, and good anti-fouling performance. The oxidation peak currents of sulfadiazine obtained on the new modified electrode increased linearly while increasing the concentration of sulfadiazine from 0.5 to 43.5 μmol/L with the detection limit of 0.17 μmol/L.  相似文献   

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