细胞冻存保护剂二甲基亚砜的细胞毒作用

二甲基亚砜（ＤＭＳＯ）是目前最好的细胞冻存保护剂，但也是一种以细胞毒性很大的化学试验剂。本研究结果表明，培养液中ＤＭＳＯ浓度为１０％时，细胞生长抑制率近１００％；１‰浓度时抑制率为３５％，即使是０．０４‰的浓度，ＤＭＳＯ对细胞的生长也有不利的影响。我们认为，培养液中残存的ＤＭＳＯ是冻存细胞复苏后出现的细胞毒现象的主要原因。因此我们提出，冻存细胞时操作过程要迅速；细胞融化务必洗涤，尽量去除ＤＭＳＯ，     

四种抗冻剂20℃时对小鼠生精上皮单细胞存活率的影响

将小鼠生精上皮单细胞置20℃含不同抗冻剂的冻存液中一定时间后，台盼蓝染色测定细胞存活率，以筛选冷冻保存小鼠生精上皮细胞的侯选抗冻剂及使用浓度。结果，20℃30min，10％浓度的二甲基亚砜（DMSO）、丙二醇（PG）及乙二醇（EG）对7日龄小鼠生精上皮单细胞存活率均无显著影响，而10％甘油（G）则使细胞存活率显著下降；20℃ 30min,10%浓度的DMSO、PG、EG及G对成年小鼠生精上皮单细胞存活率均无显著影响；20℃ 5min,25%浓度的DMSO、PG、EG及G均使7日龄及成年小鼠生精上皮单细胞存活率显著下降。实验结果表明，10％DMSO、PG及EG可作为7日龄小鼠生殖细胞慢速冷冻保存时的侯选抗冻剂，10％DMSO、PG、EG及G可作为成年小鼠生殖细胞慢速冷冻保存时的侯选抗冻剂；在高浓度抗冻剂超速冷冻保存小鼠生殖细胞时，平衡时间应短于5min，或在4℃进行。     

日本血吸虫童虫液氮冷冻保藏期的研究

日本血吸虫童虫经２４ｈ到２年冻藏后，其活力和感染率与冻藏时间长短不相关，与冻存培养液的ｐＨ相关，最佳ｐＨ为７。冻藏５０ｄ传至Ｆ４，冻藏２年传至Ｆ１。童虫及其子代在终宿主小鼠和中间宿主钉螺体内的移行、生长、发育、繁殖、传代、性别比率及对终宿主的致病力，同相应对照组无明显差异，由此证明日本血吸虫童虫可用液氮冻藏长期保种。     

牛皮肤成纤维细胞的体外培养与冻存

利用牛皮肤组织块直接培养法，得到牛皮肤细胞的原代培养物，再用酶消化法和反复贴壁法处理，能够纯化成纤维细胞。成纤维细胞的冻存是通过选用6种分别含有二甲基亚砜（DMSO）、甘油（GL）及乙二醇（EG）的保护液，以相同的冻前处理方法，对牛皮肤成纤维细胞进行缓慢冷冻，冰箱预冷平衡1－2h，逐步投入液氮（－196℃）中保存，再经37℃水浴解冻，Hanks液脱保护剂，以贴壁率评价冻存效果。结果表明，20％DMSO保护液对牛皮肤成纤维细胞表现出较好且稳定的冷冻保护效果，其平均贴壁率达87．9％。     

青藏高原牛精液超长期保存效果的研究

2013年6～7月笔者抽检了252剂本单位液氮超低温保存（0～35年）的海福特、利木赞、荷斯坦、西门塔尔、大通牦牛等九个品种牛两种剂型的冷冻精液,进行保存效果观察。结果表明,颗粒冻精（63剂）抽检日的平均活力为36．66％,最长保存时间为35年;细管冻精（189N）抽检日的平均活力5h36．94％,最长保存时间为14年。冻精活力均符合《牛冷冻精液》国家标准。从而证明,超低温冷冻精液保存不仅可用于生产实践,而且是保存动物种质资源的一种方法,对育种工作具有重要意义。     

成年小鼠生精小管及睾丸的冷冻保存

采用含不同浓度抗冻剂二甲基亚砜(DMSO)、乙二醇(EG)、丙二醇(PG)及丙三醇(G)的DMEM培养基作为冻存液,对成年小鼠生精小管及完整睾丸进行慢速冷冻,液氮保存,37 ℃水浴复苏,并测定细胞复苏率。结果表明,成年小鼠生精小管在50 mL/L、100 mL/L 及150 mL/L DMSO冻存液中的细胞复苏率分别为92.6%、93.4%及69.4%,在50 mL/L、100 mL/L及150 mL/L PG 冻存液中的细胞复苏率分别为94.2%,93.3%及66. 9%,在50 mL/L、100 mL/L 及150mL/L EG 冻存液中的细胞复苏率分别为87.2%、91. 0%及62. 6%,在50 mL/L、100mL/L及150 mL/L G冻存液中的细胞复苏率分别为90.0%、90.5%及67.1%。各种抗冻剂的最高细胞复苏率之间差异不显著(P> 0. 05 )。成鼠完整睾丸在含100 mL/LDMSO、PG、EG或G的冻存液中的细胞复苏率分别为56.0%、50.0%、50.2%及50.2%。结果显示,DMSO、PG、EG 及G 均适宜用作成年小鼠生精小管的抗冻剂,最佳使用浓度均为50 mL/L~100 mL/L。完整睾丸冷冻后的细胞复苏率低于60%,仍需进一步研究。     

丙硫咪唑混悬液的稳定性试验观察

对研制成功的丙硫咪唑混悬液进行多项稳定性试验。试验结果：保存４５个月时主药标示量为９１．５３％，在“质量标准”规定的９０％—１１０％范围内；２４ｈ沉降容积比，杭州药厂的原料制剂为６０％—９０％，宁夏化工实验厂的原料制剂为４０％；本剂保存３０、４５、６４个月的药物粒度为１．５７—５．９０μｍ；保存２—４年时对绵羊胃肠道线虫和绦虫的虫卵减少率保持１００％；保存１９、３４、４５个月，在５０ｍｇ／ｋｇ剂量时均未出现毒副作用；本剂经１２０℃４０ｍｉｎ处理或－５０℃下２４ｈ处理，药效不变。     

秸秆的调制方法

１秸秆微贮将秸秆发酵活干菌种倒入２５０ｇ水中分溶解，然后在常温下放置１～２ｈ，将复活好的菌剂倒入充分溶解的１％食盐水中搅拌，秸秆用切碎机碎成４～８ｃｍ的小段，然后铺放到微贮池中，每铺放２０～５０ｃｍ秸秆喷洒一次菌液，然后搅拌均匀，直到秸秆高于微贮池面...     

冷冻精液的贮运、保管及使用应注意的事项

在家畜繁改实际工作中，安全的保管贮运是保证冻精存活力，提高受胎率的重要环节。1液氮生物容器的质量及保存1．1液氮罐是保存冻精的必需品，新买来的或长期没有使用过的旧罐，在使用前必须严格仔细检查，查看外部有无破损（特别是真空抽气嘴），第1次充满液氮罐要观察24h，正常情况下罐体上下的温度一致，罐盖外部不挂霜，取下罐盖后罐内雾气不外溢而下沉。用手触摸罐体外壁上下温度均衡，用称量法24h重量消耗不大于100g可用。     

日本血吸虫童虫冷冻保藏复苏后生活史循环的研究

本文报告了日本血吸虫童虫经液氮冻藏复苏后的生活史循环的情况。童虫冻藏３６天和５０天后腹腔注射感染小鼠，亲代成虫回收率为９．０和８．９％。感染鼠肝内的子代虫卵孵出的子１代毛蚴感染钉螺，感染率为５９和６７％；平均每个钉螺第１次逸出的子１代尾蚴数为８００～９００条。子１代尾蚴感染小鼠后，其子１代成虫回收率为５５和５６％。合抱雌、雄成虫的体长、性腺的发育和虫体对宿主的致病力与正常途径感染者无明显差异。     

伊氏锥虫变异表面糖蛋白抗原双抗体夹心ELISA检测方法的建立及初步应用

A double antibody sandwich ELISA for detection of Trypanosoma evansi variant surface glucoprotein (VSG) antigen was established by using two monoclonal antibodies against Trypanosoma evansi VSG antigen.The result of sensitivity showed when positive serum was diluted to 3200 doubles, its D_{450 nm} value was still greater than the critical value of positive and negative,and specificity test result showed that there was no cross reaction with the antigens of Theileria,Toxoplasma gondii,Chlamydia and Fasciola gigantica.82 clinical sera were detected by this double antibody sandwich ELISA and its positive rate was 9.76%.The experiment results demonstrated that this double antibody sandwich ELISA for detection of Trypanosoma evansi VSG antigen had good detecting sensitivity and specificity,and could be used as an effective method for clinical detecting buffalo Trypanosoma evansi disease.     

不同浓度甘油和pH对DEAE-纤维素柱分离伊氏锥虫效果的影响

在不同ｐＨ条件下以不同浓度甘油破坏鼠红细胞后,用ＤＥＡＥ－５２纤维素柱层析分离纯化伊氏锥虫（Ｔｒｙｐａｎｏｓｏｍａｅｖａｎｓｉ）,结果表明在ｐＨ７．４时,２０％甘油能溶解大约９５％的大、小鼠红细胞;经此处理后,对Ｔ．ｅｖａｎｓｉ的回收率和活力无不良影响,可明显提高其分离纯化效果。作者还观察了渗透压和ｐＨ条件改变对Ｔ．ｅｖａｎｓｉ的影响。     

Post-thawing viability of vaccines for bovine babesiosis and anaplasmosis cryopreserved with glycerol

Live frozen vaccines containing Babesia bovis, Babesia bigemina or Anaplasma centrale were prepared using glycerol as cryoprotectant and stored in liquid nitrogen. The viability of the vaccines was tested inoculating calves 1 h (n = 12), 2 h (n = 12), 12 h (n = 6) and 24 h (n = 6) after thawing. Babesia bovis and A. centrale were detected in thin and/or thick blood smears in all vaccinated calves; however, 1 of 12 calves inoculated 1 h after thawing and 3 of 6 calves inoculated 24 h after thawing did not develop a B. bigemina parasitaemia. The longer post-thawing durability of frozen vaccines cryoprotected with glycerol compared with those cryoprotected with dimethyl sulfoxide, presented by other authors, will extend their use under field conditions.     

不同冷冻保护剂和冷冻方法对小鼠耳皮肤成纤维细胞冻存效果的影响

通过比较不同冷冻保存方法和冷冻保护剂对小鼠耳皮肤成纤维细胞冷冻-解冻复苏后细胞存活率、48h贴壁率和细胞生长曲线的影响,筛选适宜的小鼠耳皮肤成纤维细胞冷冻保存方法和冷冻保护剂。结果表明,以100mL/L二甲基亚砜(DMSO)作为冷冻保护剂进行小鼠耳皮肤成纤维细胞冷冻保存时,方法3处理组解冻复苏后细胞存活率和培养48h细胞贴壁率均高于方法2处理组(P>0.05),并分别极显著高于方法1和方法4。采用方法3进行冷冻保存时,以100mL/L DMSO作为冷冻剂的细胞贴壁率显著高于100mL/L甘油(GL)组(P<0.05),且冷冻解冻后的细胞呈现正常的分裂增殖生长模式。因此,宜选择100mL/L胎牛血清(FBS)+100mL/L DMSO+DMEM作为冷冻保护液,采用方法3进行小鼠耳皮肤成纤维细胞的冷冻保存。     

体外培养对布氏锥虫伊氏亚种药敏性的影响

用小鼠治疗试验和体外药敏试验观察了4个布氏锥虫伊氏亚种虫株在长期体外培养条件下药敏性的稳定性.各虫株的原始群体、连续培养30d和90d的群体对贝尼尔、苏拉灭、安锥赛和硫胂聚氰胺的敏感性基本相同,说明连续培养90d各虫株对上述4种抗锥虫药的敏感性无明显改变.     

锥虫长期超低温保藏方法的研究

作者观测不同保护剂、稀释液、ＰＨ值、降温方法、复苏温度、冻融次数、液相气相交替以及解冻后在普通冰瓶中存放时间对伊氏锥虫浙江虫浙江虫株的感染性及致病力的影响。在此试验基础上，又对伊氏锥虫的６个不同虫株、媾疫锥虫、铡果锥虫、布氏锥虫等４个种的９个早株，进行了超低温保藏试验和长期保藏效果观察。已测定的有效保藏期伊氏锥虫达５７４－３２００天，媾疫锥虫达２８６６天，则果锥虫达７６３天，布氏锥虫７８３天。通过     

Comparison of serological tests for Trypanosoma evansi natural infections in water buffaloes from north Vietnam

In the present study, a collection of 415 water buffalo serum samples originating from the north of Vietnam was used for evaluation of different diagnostic antibody detection methods available to detect infections with Trypanosoma evansi. The diagnostic sensitivity and specificity of a direct card agglutination test (CATT/T. evansi), an indirect card agglutination test (LATEX/T. evansi) and a newly developed antibody detection ELISA (ELISA/T. evansi) was calculated on the basis of parasitological results, obtained by mouse inoculation, and compared for all assays. The immume trypanolysis assay with the predominant T. evansi RoTat 1.2 variable antigen type was used as reference test for antibody presence. All parasitologically confirmed animals (n=8) were positive in all tests. Diagnostic specificity was highest in CATT/T. evansi (98%) followed by the ELISA/T. evansi (95%) and the LATEX/T. evansi (82%). Concordance of the variant specific immune trypanolysis test with the other tests was calculated and revealed that few (1-8%) false positive results were actually due to a specific reactions, and that LATEX/T. evansi and ELISA/T. evansi detected more immune trypanolysis positives than the CATT/T. evansi. It was concluded that, apart from the immune trypanolysis test, which is not generally applicable, ELISA/T. evansi with a 30% positivity cut-off and LATEX/T. evansi, thanks to their superior capacity of detecting T. evansi specific antibodies, would be suitable as epidemiological tools detecting both active infections and persisting T. evansi specific antibodies. The ELISA/T. evansi with a 50% positivity cut-off and the CATT/T. evansi on the other hand, seem more appropriate to detect true infected water buffaloes.     

Characterization of Trypanosoma (Trypanozoon) evansi from dromedary camels in Kuwait by isoenzyme electrophoresis

Blood from 115 camels in Kuwait was examined for blood parasites. Two camels of a local herd (1.7%) were found to be infected with Trypanosoma (Trypanozoon) evansi and three camels (2.6%) with microfilarial nematodes. The Trypanosoma stocks isolated from these two camels were screened for isoenzyme patterns of 10 enzymes using thin-layer starch-gel electrophoresis. The results revealed that these two stocks were identical to camel stocks of T. evansi from certain countries in Africa, as well as to two stocks isolated from dogs in Kuwait. This is the first record of Trypanosoma (Trypanozoon) evansi isolates and microfilariae from camels in Kuwait.     

Evaluation of an antibody-ELISA using five crude antigen preparations for the diagnosis of Trypanosoma evansi infection in cattle.

Attempts were made to improve the accuracy of an antibody-detection ELISA for the detection of Trypanosoma evansi infection in cattle by improving the method of preparation of the crude antigen used. An IgG-ELISA was performed with five different antigen preparations: crude soluble antigen, soluble and insoluble fractions of crude antigen treated with 0.1% formalin and whole formalin-fixed trypanosomes treated with either trypsin or 2-mercaptoethanol. An IgM-ELISA using crude soluble antigen was also performed. Each ELISA was evaluated using serum from 44 Indonesian cattle infected with T. evansi and 262 uninfected cattle from Australia. There was no significant difference between the sensitivity or specificity of the IgG-ELISA using each of the five antigens. The IgM-ELISA using a crude untreated lysate was significantly less sensitive (p<0.05) than the IgG-ELISA using the same antigen, trypsin-treated antigen or the 0.1% formalin-treated soluble antigen (68, 64 and 64%, respectively). These results show that these modifications to the method of producing crude antigens for the Ab-ELISA does not improve the accuracy of diagnosis of T. evansi infection in cattle.     

The development and validation of an antibody-ELISA to detect Trypanosoma evansi infection in cattle in Australia and Papua New Guinea

Trypanosoma evansi is exotic to Australia and Papua New Guinea (PNG). However, it might have been introduced to Papua (Indonesia); thus, there is a risk of it entering PNG and thence Australia. Because of logistical difficulties in PNG and northern Australia, surveillance for T. evansi must rely on serological tests. The accuracy of an Ab-ELISA using a detergent extract of T. evansi and three antigen fractions purified from the detergent extract using stepwise precipitation with saturated ammonium sulphate (AS) were compared. The ELISA using the AS 40-50% fraction had greater discriminatory power compared to the ELISA using the other antigen fractions. This ELISA then was compared with two commercial tests: the Card Agglutination Test for trypanosomiasis/T. evansi (CATT) and Suratex. CATT/T. evansi at 1/4 serum dilution has higher sensitivity and the ELISA has higher specificity. There is no likely benefit in combining antibody detection tests to improve the accuracy of diagnosis. Furthermore, the combination of Suratex (which was independent of the antibody tests) with the CATT or the ELISA did not improve the sensitivity. None of the tests was sufficiently sensitive to be used confidently to determine freedom from infection in animals imported into Australia from countries where T. evansi infection is endemic.