青藤碱通过调控NF-kB信号通路抑制胰腺癌Capan-1细胞增殖并诱导细胞凋亡

目的 探讨青藤碱(Sinomenine, SIN)对胰腺癌Capan-1细胞增殖及凋亡的影响。方法 CCK8法检测细胞活力,光学显微镜下观察细胞凋亡形态,DAPI/TUNEL双染检测细胞凋亡,流式细胞术Annexin V-FITC/PI法检测细胞凋亡率,Western blot检测裂解型Caspase-3蛋白(cleaved caspase-3)、细胞核内NF-κB(Nuclear factor-kappa-binding)蛋白表达。结果 CCK8结果表明青藤碱抑制胰腺癌Capan-1细胞增殖,并具有时间浓度依赖性;光学显微镜观察结果表明,在青藤碱作用下,Capan-1细胞皱缩、变圆、脱落增多;DAPI/TUNEL染色结果表明,在青藤碱作用下,Capan-1细胞凋亡增多;流式细胞术Annexin V-FITC/PI结果表明,在青藤碱作用下,Capan-1细胞凋亡率增高;Western blot结果表明,在青藤碱作用下,Capan-1细胞cleaved caspase-3、核内NF-κB表达降低,NF-κB信号通路激活剂TNF-α逆转青藤碱对Capan-1细胞增殖的抑制作用、凋亡率的升高作用和cleaved caspase-3表达的下调作用。结论 青藤碱通过调控NF-κB信号通路抑制胰腺癌Capan-1细胞增殖并诱导细胞凋亡。     

白藜芦醇预处理对心肌细胞缺血/再灌注损伤的细胞凋亡的影响

目的观察白藜芦醇预处理对心肌细胞缺血再灌注损伤的细胞凋亡的影响。方法培养乳鼠心肌细胞,模拟I/R损伤,随机分为阴性对照组、缺血再灌组及白藜芦醇预处理组,采用TUNEL染色法及Annexin V-FITC/PI双标记流式细胞术检测心肌细胞凋亡;底物酶解法检测caspase-3活性;免疫组织化学法结合计算机图像分析检测心肌细胞Bcl-2/Bax蛋白的表达。结果Res预处理使得心肌细胞凋亡率由(39.7±5.4)%降至(8.3±0.8)%,caspase-3的相对活性由5.9±0.7降至2.8±0.4,P<0.05。Res预处理可使Bcl-2表达的光密度值由99.5±4.8升至138.9±8.4,Bax表达的光密度值由140.7±8.6降至125.3±5.8,P<0.05。结论白藜芦醇预处理可通过促进抗凋亡蛋白Bcl-2的表达、抑制促凋亡蛋白Bax的表达,抑制凋亡过程中关键酶caspase-3的活性,减少I/R引起的心肌细胞凋亡。     

乙肝病毒x蛋白结合蛋白抑制阿霉素诱导HepG2细胞凋亡的机制研究

目的探讨乙型肝炎病毒x蛋白结合蛋白(hepatitis Bvirus x-interacting protein,HBXIP)抑制阿霉素(doxorubicinhydrochloride,DOX,adriamycin,ADM)诱导HepG2肝癌细胞凋亡的作用及可能的分子机制,为研究肝细胞癌的临床耐药性奠定基础。方法以建立的稳定高表达HBXIP基因的HepG2细胞系为研究对象,分别用不同浓度的DOX处理高表达HBXIP组及对照组细胞,MTT法检测细胞的生存率,DAPI染色及Annexin V-FITC/PI染色检测细胞凋亡,免疫印迹法检测蛋白表达水平。结果 MTT结果表明,DOX能够抑制HepG2细胞的存活,但HBXIP对DOX诱导的HepG2细胞凋亡作用具有明显的拮抗效应,并抑制DOX诱导的caspase-3、caspase-9及其底物PARP的活化,同时促进Bcl-2蛋白的表达。结论 HBXIP蛋白能够抑制化疗药物DOX诱导的HepG2细胞凋亡,其机制可能与调节胱天蛋白酶家族关键因子的活性相关。     

锰超氧化物歧化酶模拟化合物对人胃癌MGC-803细胞增殖和凋亡的影响

目的观察Mn SOD模拟化合物(Mn SODm)对人胃癌MGC-803细胞增殖和凋亡的影响。方法体外培养人胃癌MGC-803细胞,MTT法观察Mn SODm对MGC-803细胞增殖的影响;用Hoechst33258染色观察MGC-803细胞形态学的变化;Annexin V-FITC/PI检测MGC-803细胞凋亡;Western blot法检测p53、cleaved caspase-3、cleaved caspase-9、Bcl-2、Bax蛋白的表达。结果 MTT法检测结果显示1~20μg·m L~(-1)Mn SODm对MGC-803细胞有显著的抑制作用,24、48、72 h的IC50分别为10.18、6.93和5.05μg·m L~(-1);20μg·m L~(-1)Mn SODm作用细胞48 h后,细胞凋亡率为(69.33±4.07)%(P<0.01);Western blot结果显示,用5、10、20μg·m L~(-1) Mn SODm处理细胞48 h后,Bcl-2表达显著降低,同时p53、cleaved caspase-3、cleaved caspase-9和Bax表达显著增加(P<0.05或P<0.01)。结论 Mn SODm对人胃癌MGC-803细胞有明显的抑制作用,可能是通过下调Bcl-2表达,增加p53、cleaved caspase-3、cleaved caspase-9和Bax表达来诱导MGC-803细胞凋亡。     

长链非编码小核仁 RNA宿主基因 7调控微小 RNA-331-3p表达影响甲状腺癌细胞增殖、迁移和侵袭的机制研究

目的 探讨长链非编码小核仁RNA宿主基因7(lncRNA SNHG7)对甲状腺癌细胞增殖、迁移和侵袭的影响以及潜在的作用机制.方法 本研究起止时间为2018年1月至2019年2月,人甲状腺细胞Nthy-ori 3-1和人甲状腺癌细胞K1、BCPAP、TPC-1购自中国科学院上海细胞库,用qRT-PCR检测SNHG7和微小RNA-331-3p(miR-331-3p)的表达水平;将si-NC组(转染SNHG7干扰表达载体阴性对照)、si-SNHG7组(转染SNHG7干扰表达载体)、si-SNHG7+anti-miR-NC组(共转染SNHG7干扰表达载体和miR-331-3p抑制剂阴性对照)、si-SNHG7+anti-miR-331-3p组(共转染SNHG7干扰表达载体和miR-331-3p抑制剂),均用脂质体法转染至TPC-1细胞;采用蛋白质印迹法(Western Blotting)检测蛋白表达;四甲基偶氮唑盐比色法(MTT)检测细胞增殖;Transwell检测细胞迁移和侵袭;双荧光素酶报告基因检测实验检测荧光活性.结果 与人甲状腺细胞Nthy-ori 3-1相比,人甲状腺癌细胞K1、BCPAP、TPC-1中SNHG7的表达水平显著升高[(1.42±0.16)、(1.51±0.18)、(2.56±0.15)比(1.01±0.05)];miR-331-3p的表达水平显著下降[(0.63±0.11)、(0.60±0.10)、(0.42±0.08)比(1.00±0.06)],差异有统计学意义(P<0.05).与si-NC组相比,si-SNHG7组TPC-1细胞中细胞周期蛋白D1(Cyclin D1)、神经钙黏蛋白(N-cadherin)的表达水平显著降低,细胞周期蛋白依赖性激酶抑制剂1A(p21)、上皮钙黏蛋白(E-cadherin)的表达水平显著升高,TPC-1细胞活性显著降低[24 h:(0.20±0.06)比(0.49±0.10),48 h:(0.50±0.13)比(1.10±0.22),72 h:(0.60±0.13)比(1.60±0.10)],迁移细胞数降低[(63±8.97)个比(144±11.36)个],侵袭细胞数降低[(55±10.03)个比(136±13.38)个],差异有统计学意义(P<0.05).SNHG7可靶向调控miR-331-3p的表达.抑制miR-331-3p表达可逆转干扰SNHG7对TPC-1细胞的作用.SNHG7可靶向调控miR-331-3p的表达.抑制miR-331-3p表达可逆转干扰SNHG7对TPC-1细胞的作用.结论 干扰SNHG7可通过上调miR-331-3p抑制TPC-1细胞的恶性生物学行为.     

志苓胶囊通过激活caspase-3抑制K562细胞增殖和诱导细胞凋亡

目的研究志苓胶囊(ZLJN,抗癌复方Ⅱ号)对人慢性髓系白血病K562细胞株增殖及凋亡的影响。方法将志苓胶囊按其不同中西药成分比例配制成中药、西药和复方组,与K562细胞共培养后,采用MTT法、集落形成实验分别检测细胞存活率和集落形成率;Annexin V-FITC/PI标记法、DNA倍体分析及DNA片段化分析检测细胞凋亡;流式细胞仪检测caspase-3活性;Western blot法检测caspase-3酶原(pro-caspase-3)表达。结果不同药物组与K562细胞共培养后,细胞生长受抑制,集落形成率降低。Annexin V-FITC/PI法检测到早期凋亡细胞;DNA倍体分析可见亚二倍体峰(凋亡峰);琼脂糖电泳见典型的DNA梯状带。流式细胞检测caspase-3活性增强,Western blot检测pro-caspase-3表达减弱。结论志苓胶囊可有效抑制K562细胞增殖,诱导其凋亡,其作用机制可能与caspase-3活性增强有关。     

香菇多糖对甲状腺癌细胞生物学行为的影响

目的 研究香菇多糖(LNT)通过调控磷脂酰肌醇-3激酶/蛋白激酶B(PI3K/Akt)信号通路对甲状腺癌细胞生物学行为的影响。方法 将甲状腺癌TPC-1细胞分为空白组(常规培养)和低、中、高剂量实验组(20、40、60μmol·L^-1 LNT);另用不同剂量PI3K抑制剂LY294002(0、5 mg·L^-1)处理甲状腺癌TPC-1细胞，根据浓度分为对照组和LY294002组。以噻唑蓝(MTT)法检测细胞增殖能力，以Transwell实验检测细胞迁移及侵袭情况，以流式细胞术检测细胞凋亡及细胞周期，以蛋白质印迹法检测PI3K、磷酸化PI3K(p-PI3K)、Akt、磷酸化Akt(p-Akt)蛋白表达。结果 香菇多糖可呈时间及浓度依赖性抑制甲状腺癌TPC-1细胞增殖率(P<0.05)。空白组和低、中、高剂量实验组细胞迁移数分别为(127.67±8.09)、(98.00±5.76)、(77.67±6.25)、(38.33±5.13)个；细胞侵袭数分别为(144.50±12.50)、(109.67±6.02)、(83.00±8.07)、(50....     

小白菊内酯对人非小细胞性肺癌H1975细胞凋亡、侵袭与迁移的影响

目的探究小白菊内酯(parthenolide, PTL)对非小细胞性肺癌细胞株H1975凋亡、侵袭和迁移的影响及其可能机制。方法 MTT法和集落克隆实验检测PTL对H1975细胞增殖的影响;Annexin V-FITC/PI双染、流式细胞仪检测PTL对H1975细胞凋亡的影响;Transwell实验检测PTL对H1975细胞侵袭和迁移的影响;Western blot检测细胞凋亡、侵袭和迁移相关蛋白,以及PI3K/Akt信号通路相关蛋白的表达。结果 MTT和集落克隆实验结果显示,随着PTL浓度的增加,H1975细胞的增殖明显受到抑制,与对照组相比,差异均具有统计学意义(P<0.05);Annexin V-FITC/PI双染结果显示,PTL能明显诱导H1975细胞发生凋亡(P<0.01);Transwell实验结果显示,PTL能明显抑制H1975细胞侵袭和迁移(P<0.01);Western blot结果显示,PTL明显上调H1975细胞Bax蛋白表达,下调Bcl-2、HIF-1α、MMP-9、Akt、p-Akt(Ser473)蛋白的表达(P<0.05),同时使caspase-3蛋白发生裂解。结论 PTL能明显诱导非小细胞性肺癌H1975细胞发生凋亡,抑制其侵袭和迁移,作用机制可能与PTL抑制PI3K/Akt信号通路有关。     

棕榈酸诱导小鼠精原细胞株GC-1细胞凋亡的作用机制

目的 从内质网应激(endoplasmic reticulum stress, ERS)角度探讨棕榈酸(palmitic acid, PA)诱导小鼠精原细胞株GC-1细胞凋亡的机制。方法 将GC-1细胞分为正常组(Control)、溶剂对照组(Vehicle)和不同浓度PA处理组(100、150、200、250μmol·L^-1)。MTT法检测细胞增殖活力，流式细胞术Annexin V-FITC/PI双染法检测细胞凋亡情况；Caspaes-3活性检测试剂盒检测凋亡蛋白caspase-3的活性；Western blot检测凋亡相关蛋白和ERS相关蛋白表达水平。结果 PA处理GC-1细胞48 h后，细胞增殖活力显著下降，细胞凋亡率上升，凋亡蛋白caspase-3活性增高，结果均具有浓度依赖性；PA可明显增加GC-1细胞促凋亡蛋白cleaved-caspase-3的表达水平，明显降低抑凋亡蛋白BCL2的表达水平，同时上调ERS相关蛋白GRP78、CHOP、p-IRE1、XBP1的表达水平，但对p-PERK、PERK、p-eIF2α、eIF2α、ATF4以及ATF6的表达无...     

吴茱萸碱在诱导人黑色素瘤A375-S2细胞凋亡过程中对SIRT1和p53蛋白的影响

目的研究吴茱萸碱(evodiamine)在诱导A375-S2细胞凋亡过程中对SIRT1和p53蛋白表达的调控。方法电镜观察吴茱萸碱诱导细胞凋亡过程中细胞形态的变化。Western blot方法分析药物作用后对SIRT1蛋白和p53及其下游p21蛋白表达的影响。结果经15μmol.L-1吴茱萸碱处理24 h的A375-S2细胞表现出典型的凋亡特征,即细胞表面微绒毛消失、胞质空泡化、染色质浓集、边聚。在吴茱萸碱诱导A375-S2细胞凋亡过程中,SIRT1蛋白的表达下降,p53和p-p53的表达有所上升,其下游p21蛋白也被激活。结论在吴茱萸碱诱导的A375-S2细胞凋亡中,p53及其下游p21蛋白被活化,SIRT1蛋白表达被下调。     

高速逆流色谱分离纯化远志中3,6′-二芥子酰基蔗糖酯和远志蔗糖酯A

目的研究制备型高速逆流色谱从远志中分离纯化3,6′-二芥子酰基蔗糖酯和远志蔗糖酯A。方法采用分析型高速逆流色谱摸索制备型高速逆流色谱的分离条件。根据化合物的光谱数据,鉴定结构。结果选择乙酸乙酯-正丁醇-水（4：1：5,v/v/v）为制备型高速逆流色谱分离的溶剂系统,从400mg远志样品中得到3,6′-二芥子酰基蔗糖酯和远志蔗糖酯A分别为24.6mg和45.2mg,HPLC检测纯度分别为93%和95%。结论本法简单快速,为远志及同属植物中糖酯类化合物的制备提供了一种新的分离方法 。     

Effect of earthworm active protein on fibroblast proliferation and its mechanism

Context: Earthworms have been used as a traditional medicine in China from thousands of years. In recent years, research has demonstrated that earthworm extracts might promote wound healing; however, its mechanism is still unknown.

Objective: The study investigates the mechanism and effects of earthworm active protein (EAP), on mouse embryonic fibroblast (NIH/3T3) proliferation.

Materials and methods: The effects of earthworm active protein (EAP) in different concentrations (0, 25, 50, 100, 150, and 200?μg/mL) on NIH3T3 cell were detected by the MTT and Brdu incorporation assay (50, 100, and 150 μg/mL). The effects of EAP (37.5, 75, and 150?μg/mL) on the cell cycle were detected by flow cytometry. The cell signaling pathways of EAP-promoting NIH3T3 cell proliferation were studied by the MTT and Western blot by using different signaling pathway inhibitors.

Results: The results showed that EAP (50, 100, and 150 μg/mL) could promote NIH3T3 fibroblasts proliferation (36.4 ± 4.4%, 59.1 ± 4.9%, and 71.5 ± 5.7%). The mechanism of EAP promoting NIH3T3 cell proliferation should be as follows: EAP elevated cyclin D1 expression by activating MEK/ERK signaling pathway, and then promoted cell cycle from G1 to S phase, finally caused the proliferation of NIH3T3 cell. PI3K signaling pathway may be the upstream of MEK/ERK signaling pathway.

Discussion and conclusion: The study demonstrates that EAP is effective in promoting effects on proliferation and migration activity of NIH3T3 cell, and the proliferation activity of EAP on NIH3T3 cell may be achieved through the PI3K→Rac→PAK→MEK signaling pathway.     

Synthesis of tritium labelled (R) and (S)-3-aminoquinuclidine: A ubiquitous component of serotonin receptor ligands,part II

(S)-3-Aminoquinuclidine-³H 10c-S having a specific activity of 66 Ci/mmol was prepared in eight steps from Isonicotinic acid ( 2 ). Reduction of 2 with carrier free tritium gas over PtO₂ in DMF gave isonipecotic acid-³H 3c . Conversion to α-bromo ketone 5c followed by cyclization afforded 3-quinuclidone-³H 6c . Racemic 3-aminoquinuclidine-³H 8c was prepared by conversion of 6c to oxime 7c followed by reduction with NaBH₄/NiCl₂·6H₂O. Racemic 8c was resolved with (R)-methylbenzyl isocyanate. Hydrolysis of 9c-S.R afforded (S)-3-aminoquinuclidine-³H 10c-S . The enantiopurity was >99.5% (S).     

Comparative evaluation of cytotoxicity and phototoxicity of mono and diacylglycerol amino acid-based surfactants

Extensive efforts have been made, recently, to find surfactants with lower irritancy potential than those presently commercially employed in pharmaceutical and cosmetic preparations. Cytotoxic and phototoxic effects of novel mono and diacylglycerol amino acid-based surfactants (glutamic acid, or arginine) were evaluated.All tested surfactants showed a clear concentration–response relationship to two immortalized cell lines, murine fibroblast cell line, 3T3, and one human keratinocyte cell line, HaCaT, demonstrated by and decrease of NR uptake. Concentrations resulting in 50% inhibition of NR uptake (IC₅₀) range from 30 to 300 μg mL⁻¹.The potential phototoxicity which could result in irritant products, was determined by modulated cytotoxicity via the resazurin reduction to resorufin and neutral red uptake (NRU) endpoints. Surfactants with two chains showed, in general, less cytotoxic but higher phototoxic effect than surfactants with only one chain.     

pkc-α、caspase-3在大肠癌中的表达及意义

目的:研究pkc-α和caspase-3在大肠癌中的表达及其与大肠癌临床病理特征的关系。方法:利用S-P法检测48例大肠癌和10例大肠腺瘤以及15正常大肠黏膜组织中pkc-α和caspase-3基因的蛋白表达。结果:①在大肠腺癌、腺瘤和正常大肠黏膜中pkc-α和caspase-3的阳性表达率分别为58.3%(28/48),66.7%(32/48);90%(9/10),100%(10/10);86.7%(13/15),93.3%(14/15),pkc-α和caspase-3在大肠癌中阳性表达率显著低于正常黏膜和良性腺瘤(P<0.05)。②pkc-α和caspase-3的表达与大肠癌的临床病理分级有关,随着病理分级的增加,其表达率逐渐降低;与性别、年龄、淋巴结转移及D ukes分期均无关(P>0.05)。③大肠癌组织中pkc-α和caspase-3蛋白的表达无明显相关性(P>0.05)。结论:pkc-α和caspase-3蛋白的低表达在大肠癌的发生发展中起着重要的作用,可作为大肠癌临床评价肿瘤生物学行为及病理诊断的有用指标。     

Metabolism of Digoxigenin,digoxigeninmonodigitoxoside and digoxigeninbisdigitoxoside in rats

Summary The biliary and renal excretion products after i.d. administration of ³H-digoxigenin, ³H-digoxigenin-mono-digitoxoside and ³H-digoxigenin-bis-digitoxoside were studied in biliary fistula rats 65% and 58% of the given dose were excreted in bile and 10% and 5% in urine within 12 h after administration of mono-and-bis-glycoside respectively. Within 8 h, 45% and 4% of the given dose was eliminated in bile and urine after administration of digoxigenin.93–95% of the excreted radioactivity consisted of CHCl₃-soluble substances after administration of the bisglycoside, whereas the CHCl₃-soluble fraction accounted for only 30–45% of the biliary eliminated radioactivity after administration of the monoglycoside and the genin. The main excretion product after administration of bis-digitoxoside was the unchanged bisglycoside. After administration of monodigitoxoside, digitoxoside, the CHCl₃-soluble fraction in bile and urine was mainly represented by the monoglycoside and the 3-epigenin. Only traces of 3-ketogenin and no digoxigenin at all were detectable. The only CHCl₃-soluble excretion product in bile after administration of digoxigenin was its epimer, while in urine a few per cent of unchanged digoxigenin and 3-ketogenin could be identified.The CHCl₃-insoluble fraction after administration of bis- and-monodigitoxoside consisted of conjugation products with glucuronic and sulfuric acid. The monoglycoside was identified as the main conjugation partner after encymatic splitting of the polar fraction with -glucuronidase and sulfatase. Therefore the hydroxyl in C₃ of the steroid moiety cannot be conjugated preferentially with glucuronic or sulfuric acid during the metabolic decomposition of glycosides. This finding led to a degradation scheme of digoxin already discussed. Due to rapid metabolic inactivation of the monoglycoside to polar metabolites a therapeutic significance of this substance is very unlikely.     

1,25-二羟基维生素D_3抑制K562细胞增殖及其机制

目的观察1,25二-羟基维生素D3〔1,25(OH)2D3〕对白血病细胞株K562增殖的影响并初步探讨其作用机制。方法间接免疫荧光法鉴定维生素D受体(VDR)在K562细胞的表达;四噻唑蓝法(MTT)、AO/EB、流式细胞PI单染分析细胞生长抑制率、细胞凋亡率及细胞周期;比色法检测凋亡信号蛋白———天冬酰胺特异酶切的半胱氨酸蛋白酶-3(Caspase-3)活性。结果①K562细胞核阳性表达VDR;②10-8mol.L-11,25(OH)2D3可明显抑制K562细胞增殖,促进凋亡,凋亡率从4.1%(对照组)增至26.5%,P<0.01;③1,25(OH)2D3作用后K562细胞的Caspase-3活性增加,P<0.05,提示细胞凋亡伴随着Caspaes-3活性升高。结论1,25(OH)2D3可明显抑制K562细胞增殖,促进细胞凋亡,其作用机制与Caspase-3活性增加相关。     

表没食子儿茶素没食子酸酯对Reh细胞增殖及RUNX3基因甲基化状态的影响

目的:观察表没食子儿茶素没食子酸酯(EGCG)对白血病细胞系Reh细胞增殖抑制作用及对RUNX3基因启动子区甲基化状态及表达的影响,探讨Reh细胞RUNX3基因的失活机制及EGCG对RUNX3基因表达的调控。方法:体外培养Reh细胞,用5、10、15和20μg/mL EGCG与Reh细胞孵育,采用MTT法检测EGCG对Reh细胞增殖活性的影响;采用流式细胞术检测EGCG对Reh细胞凋亡的影响;采用甲基化特异性PCR(MSP)检测RUNX3基因启动子区域的甲基化情况;采用RT-PCR、Western blot法分别检测RUNX3 mRNA、蛋白的表达。结果:EGCG对Reh细胞生长有明显的抑制作用,并有时间及剂量依赖性;EGCG可促进Reh细胞发生凋亡,随着EGCG浓度的增加,细胞凋亡率逐渐增加;MSP法结果显示EGCG处理后RUNX3基因启动子高甲基化的区域发生去甲基化,EGCG能够诱导Reh细胞RUNX3基因mRNA和蛋白的重新表达,具剂量依赖性。结论:EGCG可明显抑制Reh细胞的增殖,并诱导Reh细胞中异常甲基化的RUNX3基因去甲基化,使RUNX3基因恢复表达,这可能是其抗肿瘤的重要机制。     

Molecular cloning and characterization of Phoneutria nigriventer toxins active on calcium channels.

The aim of the present study was the molecular cloning of toxins active on calcium channels expressed by the spider Phoneutria nigriventer. Clones encoding the toxins Pn3-3A, Pn3-4A, Tx3-5, Pn3-5A, Tx3-6, Pn3-6A and Pn3-6B were identified from a cDNA library derived from the venom gland of this spider, revealing toxins of 49, 76, 45, 39, 55 and 58 amino acids residues, respectively, with polypeptide precursors being composed of three major portions: a signal peptide, a propeptide and finally, the mature toxin. A high degree of homology with the amino acid sequence was found between Pn3-3A and the neurotoxin Tx3-3 (identity of 79%), and between Pn3-4A and the neurotoxin Tx3-4 (identity of 95%). The deduced amino acid sequence for the mature polypeptides Tx3-5 and Tx3-6 confirms the polypeptide sequence previously published for these neurotoxins. In addition, the toxin Pn3-5A showed 58% identity to the Tx3-5 amino acid sequence, and the toxins Pn3-6A and Pn3-6B showed 85 and 33% identity, respectively, to the Tx3-6 amino acid sequence.     

CTMAB增敏紫外分光光度法测定制剂中的加替沙星

目的 采用紫外吸收增敏法测定加替沙星的含量.方法 以十六烷基三甲基溴化铵为增敏剂,在292 nm处测定吸光度,据标准曲线计算含量.结果 加替沙星片剂和粉针剂的测定结果与文献报道的荧光法一致.结论 所用方法简单、快速、准确、灵敏.