Apoptosis during β-mercaptoethanol-induced differentiation of adult adipose-derived stromal cells into neurons

β-mercaptoethanol can induce adipose-derived stromal cells to rapidly and efficiently differentiate into neurons in vitro.However,because of the short survival time of the differentiated cells,clinical applications for this technique are limited.As such,we examined apoptosis of neurons differentiated from adipose-derived stromal cells induced with β-mercaptoethanol in vitro using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and transmission electron microscopy.The results revealed that the number of surviving cells decreased and apoptosis rate increased as induction time extended.Taken together,these results suggest that apoptosis occurring in the process of adipose-derived stromal cells differentiating into neurons is the main cause of cell death.However,the mechanism underlying cellular apoptosis should be researched further to develop methods of controlling apoptosis for clinical applications.

Spectrofluorometry of Ions and Small Molecules Based on Conformational Changes of Specific Oligonucleotides with o-Phthalaldehyde-β-mercaptoethanol

Specific oligonucleotides such as telomere DNA and aptamer often undergo conformational changes upon ligand binding. Composite reagent composed of o-phthalaldehyde and β-mercaptoethanol（OPAME） has been extensively applied to fluorescent detection of amino compounds based on the reaction of primary amino-group, herein we proposed a general spectrofluorometry for ions and small molecules due to conformational changes upon ligand binding taking K^＋ and ATP as examples. In a borate controlled buffer medium, telomere DNA could react with OPAME, giving a thio-subtituted isoindole compound with strong fluorescence emission at 455 nm when excited at 340 nm. It was found that however, the fluorescence emission was greatly reduced in the presence of K^＋ since the formation of the quadruplex structure inhibits the reaction activity of amino-groups of telomere DNA. In order to testify the general application of OPAME reagent based on the conformational change of oligonucleotides, we further proposed a sensitive method of ATP based on its highly selective interaction with ATP-aptamer. The above mentioned applications show that the spectrofluorometry with the aid of OPAME reagent is simple, label free that is expected to be potentially general for DNA conformational change-based target detection.

Effects of β-mercaptoethanol Concentrations on Developmental Ability of Oocytes in 6-week-old Dorper Sheep

This study was conducted to investigate the effects of different concentrations ofβ-mercaptoethanol on the development ability of oocytes in Dorper sheep at the age of 6 weeks.In this study,6 Dorper sheep of 6 weeks old were chosen to induce oocyte collection in vivo by gonadotropin,and A and B grade cumulus oocyte complexes were obtained(COCs)with different concentrations of(0,50,70 and 100μmol/L)ofβ-mercaptoethanol in the mature liquid.The cleavage rate and blastocyst rate were counted after matured oocytes and capacitated sperm were co-incubated and fertilized eggs were cultivated.The results showed that compared with the cleavage rate(59.13%)and the blastocyst rate(12.17%)of the control group,the cleavage rates(60.87%,63.48%and 65.22%)and blastocyst rates(14.78%,17.39%and 21.74%)of the test groups I,II and III were higher(P>0.05),and the order was test group III>test group II>test group I>control group.The cleavage rate and blastocyst rate of the 100μmol/Lβ-mercaptoethanol group increased by 6.09 percentage points and 9.57 percentage points,respectively.It indicated that the addition of a certain amount ofβ-mercaptoethanol in the mature liquid could improve the developmental ability of oocytes and the quality of fertilized eggs of the 6-week-old Doper sheep.When theβ-mercaptoethanol concentration was within 100μmol/L,the cleavage rate and the blastocyst rate of oocytes were on the rise.The optimal concentration ofβ-mercaptoethanol in the mature liquid still needs further study.

Effects of Epidermal Growth Factor and β-mercaptoethanol on In-vitro Fertilization and Development of Oocytes from Hormone-Stimulated Lambs

[Objective]The aim was to explore optimization of system of oocytes in-vitro culture of young animals. [Method]Effects of EGF （ epidermal growth factor） and β-mercaptoethanol in maturation media on fertilization,cleavage and blastaea were researched,which were then compared with those of adult sheep. [Result]EGF in different concentrations had little effects on rates of cleavage and blastaea （ P 〉0.05） and β-mer-captoethanol in different concentrations would improve blastaea rate of oocytes,for example,100 μmol/L of β-mercaptoethanol has significant effects on balstaea rate （ P 〈0.05） ,but has little effects on cleavage rate （ P 〉0. 05） . In addition,rates of cleavage and balstaea of oocytes in lamb were both lower than those of adult sheep （ P 〈0.05） ; fertilization rate of oocytes in lamb （ P 〈0.05） ,which differed little with that of adult sheep （ P 〉0.05） ,could be significantly enhanced by 100 μmol/L of β-mercaptoethanol. Furthermore,polyspermy rate was higher than that of adult sheep without β-mercaptoethanol （ P 〈0.05） ; the rate was of little differences with that of adult sheep with 100 μmol/L of β-mercaptoethanol （ P 〉 0.05） ; unfertilization rate （ 20%） in media without β-mercaptoethanol was a little higher （ P 〉0.05） than those of adult sheep （ 12.3%） and those in media with β-mercaptoethanol （ 13.5%） . [Conclusion]Developmental capacity of oocytes and fertilization rate could be improved by 100 μmol/L of β-mercaptoethanol with polyspermy rate reduced,but developmental capacity of lamb was significantly lower than that of adult sheep.

S-(2-羟乙基)-2,2-二甲基丙硫酸酯的合成研究

研究了S-(2-羟乙基)-2,2-二甲基丙硫酸酯的合成,采用三甲基乙酰氯和β-巯基乙醇作为反应物完成了硫酯键的构建,并对该反应条件进行了方法学研究。该化合物的合成工艺是在-78℃条件下,将β-巯基乙醇和三乙胺分别加入装有干燥DCM的圆底烧瓶中,缓慢滴加三甲基乙酰氯于反应体系中,允许反应升温至室温继续反应2h,该工艺方法得到82%左右的收率,且反应条件简单温和,工艺设备成本廉价,可进行大量合成,实现了操作简单、经济实惠和绿色环保的目的。

PHOTOCHEMISTRY OF HYPOCRELLIN A (V)——PHOTOREACTION OF HYPOCRELLIN A AND MERCAPTOETHANOL

I.INTRODUCTION Hypocrellin A(abbreviated HA) from Hypocrellia bambusae (B. ct Br.)sacc. growing in Yunnan Province, China, is an efficient phototherapeutic agent. Recently HA irradiation with visible light has been successfully used for the treatment of white lesions of vulva and vitiligo. In molecular level, studies on phototherapeutic mechanism have been focused on the structure, photophysical and photochemical properties of HA and its derivatives. The photoreactions, which are closely related to phototherapeutic activities, have not been re-

THE REDUCTION AND NUCLEOPHILIC ADDITION OF MERCAPTOETHANOL TO HYPOCRELLIN A

Ⅰ. INTRODUCTIONHypocrellin A （abbreviated as HA）is a perylenequinone derivative. The structure, ESR and absorption spectrum of the metastable product HAH2 produced by photoinduced net two-electron reduction of HA have been reported. The absorption spec-

Study on catalytic oxidation of planar binuclear copper phthalocyanine on 2-mercaptoethanol

Mononuclear copper phthalocyanine (CuPc) and binuclear copper phthalocyanine (Cu2Pc2) were synthesized by the phenylanhydride-urea route, and their catalytic oxidation activity on 2-mercaptoethanol was studied. Based on the experimental results, a catalytic mechanism of Cu2Pc2 on 2-mercaptoethanol has been proposed. Furthermore, the effects of pH, Cu2Pc2 concentration, and temperature on the catalytic oxidation activity were evaluated. The results showed that CuPc has no catalytic activity, while Cu2Pc2 has high catalytic oxidation activity towards 2-mercaptoethanol with the optimal activity at pH 11. The reaction can further be enhanced by increasing Cu2Pc2 concentration and temperature, due to its endothermic characteristics.

Protective Effects of Hydroxysafflor Yellow A against Oxidative Damage of β-Mercaptoethanol During Neural Differentiation of Mesenchymal Stem Cells

Objective To study the protective effects of hydroxysafflor yellow A （HSYA） against the oxidative damage caused by β-mercaptoethanol （BME） during neural differentiation of mesenchymal stem cells （MSCs） in vitro. Methods When the confluence reached 50%-60%, 4th passage MSCs were divided into three groups to culture. Gt ： normal group which was cultured using basic medium （DMEM containing 10% FBS all the time）; G2： unprotected group which was continuously cultured using basic medium for 24 h, and then cultured using pre-induction medium （DMEM containing 10% FBS and 1 mmol/L BME）; G3： protected group which was firstly cultured using protective medium （DMEM containing 10% FBS and 160 mg/L HSYA） for 24 h, and then cultured using pre-induction medium for 24 h. After these treatments as above, cell viability, relative levels of SOD/GSH and apoptosis rate were respectively detected. The expression of Bcl and Bax was examined by Western blotting. After HSYA protection and BME pre-induction, neural induction was performed. The expression of NSE and MAP-2 was respectively analyzed on cellular and molecular levels. Results Compared with unprotected group, 160 mg/L HSYA could obviously improve cells viability, maintain high level of SOD and GSH in MSCs, reduce apoptosis rate and improve the ratio of Bcl/Bax. After protection with 160 mg/L HSYA, the survival time of neuron-like cells could be extended. Immunocytochemical staining showed that after 10 h of neural induction, the differentiated neuron-like cells in protected group were still in a good state, and the mRNA levels of NSE and MAP-2 were increased during the induction course checked. Conclusion HSYA could improve the resistance of cells to the oxidative damage caused by BME.

不同水解方法对植物叶片结合氨基酸测定影响分析

为建立植物叶片结合氨基酸(bound amino acid,BAA)适宜检测方法,试验采用全自动氨基酸分析仪对4种植物叶片BAA进行测定:zuixinZG二极管,钠体系色谱柱(125 mmHR),柱后衍生光度法,570 mm/440 nm,单点校正。研究常规盐酸水解法、苯酚+盐酸水解法、β-巯基乙醇(β-mercaptoethanol,BME)+盐酸水解法、过甲酸氧化法对植物叶片17种BAA及其总量的影响。结果表明:过甲酸氧化法适合用于水稻和小麦叶片含硫氨基酸测定;BME+盐酸水解法适合用于4种植物叶片BAA测定。采用BME+盐酸水解26 h,植物叶片中多数极性正电和非极性氨基酸含量达到最大值;添加0.80%BME,植物叶片中极性正电氨基酸、负电氨基酸、中性氨基酸中的酪氨酸、胱氨酸及大部分非极性氨基酸含量达到最大值。该方法操作简单、重复性强、稳定性高,适合用于植物叶片BAA的检测。

影响对硝基苯基-β-羟乙基硫醚合成的原因分析

对硝基苯基-β-羟乙基硫醚是采用巯基乙醇工艺路线生产对位酯的第一步产物,该产物主要以对氯硝基苯和2-巯基乙醇在溶剂二甲基甲酰胺(DMF)中缩合反应而成,反应过程中加入适量的缚酸剂NaOH调节体系的pH值。通过实验研究,找出最佳合成对硝基苯基-β-羟乙基硫醚的条件。

水溶性CdSe/CdS纳米晶合成条件的优化研究

以巯基乙醇为修饰剂,在水溶液中合成了稳定的CdSe/CdS纳米晶,应用单因素法和多目标单纯形法探索合成条件。通过透射电镜观察所合成的纳米晶的形貌和大小,用紫外-可见吸收光谱和荧光光谱对其光学特性进行了表征。并且以L-色氨酸荧光量子产率0.14为标准,测量了合成的CdSe/CdS纳米晶的荧光量子产率为0.37。

邻苯二甲醛-β-巯基乙醇组合试剂可视化荧光检测多巴胺

研究发现，在碱性条件下，邻苯二甲醛和β-巯基乙醇组合试剂可与多巴胺发生化学反应生成异吲哚类化合物。当用340nm光激发时产生462nm的荧光，且荧光强度与多巴胺含量呈良好的线性关系，从而建立了一种可视化荧光检测多巴胺的新方法。在pH9．8的H3BO3-NaOH缓冲条件下，检测的线性范围为5．2×10^-8～1．7×10^-5mol／L，相关系数为0．9993，检出限（3σ）为4．1×10～mol／L。对7．0×10^-6mol／L的多巴胺进行11次平行测定，其相对标准偏差为1．4％。方法用于盐酸多巴胺注射液含量的分析，平均加标回收率为97．7％。以波长为365nm紫外灯激发多巴胺样品，可实现多巴胺可视化半定量检测。

CD38单克隆抗体对输血相容性检测干扰及其应对方案的专家共识

随着肿瘤免疫靶点的不断发现及抗体研发技术的持续变革,抗体药物在临床上的应用越来越广泛。但有些靶点不仅在肿瘤细胞上表达,而且在红细胞上也有表达,故临床上针对相应靶点抗体的应用可能会对输血相容性检测产生干扰,导致配血困难或输血延迟。本共识总结了目前克服CD38单克隆抗体(简称CD38单抗)干扰输血相容性检测的方法,并经过对不同方法的优缺点分析后,推荐在中国患者人群中使用凝聚胺和巯基还原剂[二硫苏糖醇(Dithiothreitol,DTT)或2-巯基乙醇(2-mercaptoethanol,2-Me)]处理红细胞,作为解决CD38单抗干扰输血相容性检测的方法,以消除CD38单抗带来的输血问题,为临床医师和输血科技术人员提供相应输血前工作流程的解决方案。

活性碳纤维负载钴酞菁催化氧化2-巯基乙醇的研究

将四(2,4-二氯-1,3,5-三嗪基)氨基钴酞菁以共价键形式键合在活性碳纤维(ACF)载体上,制得了活性碳纤维负载钴酞菁催化剂(ACF-CoPc),采用热重分析、原子吸收光谱和氮气等温吸附法对其进行了表征。原子吸收光谱测得金属酞菁的负载量为5.26μmol/g。氮气等温吸附法测得ACF-CoPc的比表面积为1235.9m2/g,孔径分布以2nm左右的小孔为主。以2-巯基乙醇为催化对象,采用超高效液相色谱研究了ACF-CoPc的催化氧化性能。结果表明ACF-CoPc对2-巯基乙醇具有很好的催化氧化性能,反应4h时对2-巯基乙醇的去除率高达100%,氧化产物为2,2’-二硫二乙醇。而且催化剂ACF-CoPc经6次循环使用后,对2-巯基乙醇的去除率没有持续下降,这表明该催化剂具有良好的重复使用性。

β-巯基乙醇与肝基质对日本血吸虫培养细胞的影响

目的研究β鄄巯基乙醇与肝基质对日本血吸虫培养细胞的影响。方法将18d虫龄的日本血吸虫童虫细胞联合法接种于小盖玻片上。实验被随机分为4个组,分别为对照组、β鄄巯基乙醇组、肝基质组、β鄄巯基乙醇+肝基质联合处理组。培养第7天,对各组细胞进行核仁组织区相关嗜银蛋白(AgNORs)与乳酸脱氢酶(LDH)细胞化学染色,并结合图像分析比较4个组培养细胞的AgNORs水平及LDH活性。结果与对照组比较,肝基质组、β鄄巯基乙醇组、β鄄巯基乙醇+肝基质联合处理组培养细胞的AgNORs颗粒数目、颗粒面积与核面积百分比、平均光密度以及LDH的平均光密度等4个参数均有不同程度升高(P<0.01)。其中,以β鄄巯基乙醇组培养细胞的4个参数升高最显著,β鄄巯基乙醇+肝基质联合处理组次之,肝基质组升高幅度最小。统计学分析显示,除β鄄巯基乙醇+肝基质联合处理组与β鄄巯基乙醇组之间的AgNORs及LDH平均光密度两两比较差异无显著意义(P>0.05),其余组间3个参数两两比较差异均有显著意义(P<0.01或P<0.05)。结论β鄄巯基乙醇与肝基质均能促进日本血吸虫培养细胞的增殖、代谢,但β鄄巯基乙醇的作用比肝基质显著;二者联合使用对培养细胞的增殖无协同作用。

日本血吸虫培养细胞核仁组织区相关嗜银蛋白的研究

目的 通过研究日本血吸虫成虫与童虫培养细胞核仁组织区相关嗜银蛋白(AgNORs)含量及β-巯基乙醇对培养细胞AgNORs的影响,探讨AgNORs能否作为评价日本血吸虫培养细胞增殖的指标以及β-巯基乙醇对培养细胞的促增殖作用。方法 联合法培养虫龄分别为18d和24d的日本血吸虫童虫与成虫,将童虫细胞随机分成对照组和实验组,对照组细胞与成虫细胞使用常规培养基培养,实验组在常规培养基中加入50μmoL/L β-巯基乙醇和1mmoL/L丙酮酸钠。培养第5d,运用胶银法染色,使用HPIAS-2000图像分析系统,计算培养细胞核内AgNORs颗粒数,测定银染颗粒面积与核面积的百分比和平均光密度。结果 日本童虫培养细胞(对照组)的AgNORs颗粒数目、颗粒面积与核面积百分比、平均光密度均高于成虫培养细胞。统计学分析显示,两者之间的AgNORs颗粒数日,银染颗粒面积与核面积百分比、平均光密度两两比较均有统计学差异(P<0.01或P<0.05);实验组培养细胞与对照组比较,AgNORs颗粒数目明显增多颗粒面积与核面积百分比、平均光密度均显著升高。统计学分析可知,两组细胞三组参数之间均有统计学差异(P<0.01或P<0.05)。结论 AgNORs可作为评价日本血吸虫培养细胞增殖的一个简便、敏感的指标。日本血吸虫童虫培养细胞较成虫培养细胞更具增殖潜能;

Fura-2/AM荧光法测定日本血吸虫培养细胞内游离钙离子浓度

目的 研究用钙荧光探剂 (Fura- 2 / AM)检测静息状态下日本血吸虫培养细胞内的游离钙离子浓度 ([Ca2 + ]i) ,以及β-巯基乙醇对培养细胞 [Ca2 + ]i的影响。方法 将 18d虫龄的日本血吸虫童虫制成细胞悬液 ,贴壁法接种于 30 ml培养瓶中 ,培养液为 RPMI- 16 4 0含 2 0 %小牛血清及常量抗生素。在培养的 0 - 3d,制备日本血吸虫细胞悬液 ,采用 Fura- 2 / AM钙荧光探剂测定正常静息状态下及加入β-巯基乙醇后日本血吸虫培养细胞内的 [Ca2 + ]i。结果 正常静息状态下 ,培养 0 d的日本血吸虫培养细胞内的 [Ca2 + ]i为 188.2 nmol/ L ;培养 1- 3d的 [Ca2 + ]i两两比较差异无显著性(P>0 .0 5 ) ,它们的平均值为 (187.0± 10 .7) nm ol/ L ,与培养 0 d的 [Ca2 + ]i比较 ,差异也无显著性(P>0 .0 5 )。β-巯基乙醇可使日本血吸虫培养细胞内 [Ca2 + ]i明显升高 (P<0 .0 1) ,并随浓度的增加而升高。结论 培养 1- 3d,静息状态下日本血吸虫培养细胞内的 [Ca2 + ]i比较稳定 ,β-巯基乙醇能影响日本血吸虫培养细胞内的 [Ca2 +

巯基乙醇还原法溶解羊毛角蛋白

采用巯基乙醇还原法对羊毛纤维进行溶解 ,研究了不同巯基乙醇浓度对羊毛溶解的影响 ,并用质谱法测量了溶解后蛋白质大分子的平均分子量。实验证实 。

降低“雪青”梨的外植体褐化研究

以“雪青”梨为材料,以第6代茎尖愈伤组织为外植体,采用L9 (34 )正交设计,研究不同因素对降低外植体褐化的作用。3因素设为基本培养基(A)、培养基中巯基乙醇(B)和活性炭(C)浓度;每因素设3个水平,A分别为1 /4MS,MS和1 /2MS无机盐浓度,B分别为0. 5, 0. 1和0g/L,C分别为2. 5, 5和0g/L。外植体接种在不同的MS基本培养基中(均含2, 4-D2mg/L, 6-BA0. 1mg/L,琼脂8g/L,蔗糖30g/L,pH=5. 8),于25±1℃, 2 000lx光照培养, 30d后统计褐化率。试验结果表明:降低外植体褐化的最优水平组合为A1B1C2,B,C对试验结果的影响达显著水平(P【 0. 05),不同水平间差异显著(P【 0. 05)。以1 /4MS为基本培养基, 并于1 /4MS+MC0. 5g/L+AC5g/L培养基中光照培养, 褐化率可降至5 %。