Sf9昆虫细胞悬浮培养工艺的研究

对Sf9昆虫细胞在不同培养基、培养基中是否添加血清及不同生物反应器中的培养工艺进行了研究,发现Sf9细胞在Sf900Ⅱ无血清培养基中生长比在添加10％小牛血清的Grace培养基中更好,在Sf900Ⅱ无血清培养基14 L搅拌式生物反应器分批培养细胞密度可达1.4×107/mL.过程生化特性分析表明,总氨基酸的消耗及主要代谢副产物特别是乳酸及游离氨的积累是培养后期细胞密度降低及活性下降的重要原因.本研究为Sf9细胞生物反应器培养工艺优化及利用昆虫杆状病毒蛋白表达系统高效表达重组蛋白生产亚单位疫苗奠定了良好基础.     

PK15细胞在不同培养条件下的生长情况

PK15细胞在多种兽用疫苗的研究和生产中被广泛培养。在生产中培养生长状态良好的PK15细胞,是生产优质疫苗的前提。随着疫苗生产工艺的不断更新迭代,细胞培养的方式也不断增加,目前常见的培养方式有方瓶、转瓶、生物反应器等。为了给生产制定更加优化的培养策略,本文探讨了PK15细胞在方瓶、转瓶、生物反应器三种不同培养条件下的生长情况。通过分析每次细胞培养前的分种密度、培养72 h细胞密度、细胞增长倍数并观察24 h、48 h、72 h的细胞状态,确定细胞的生长情况。结果表明,就对于细胞生长繁殖而言,无论哪种培养方法,该细胞均能很好生长。培养72 h,就细胞增长倍数而言,各培养系统有所区别,表现为方瓶倍增为10～30倍,转瓶为5～10倍,生物反应器为8～12倍。     

氨和乳酸对悬浮培养的BHK-21细胞生长和胞内酶活性的影响

为了研究氨和乳酸对悬浮培养的BHK-21细胞生长和细胞内酶活性的影响,用添加了不同浓度氨和乳酸的培养基悬浮培养BHK-21细胞,间隔12 h取样,比较细胞的生长状况,检测细胞代谢过程中营养物质的消耗和细胞内琥珀酸脱氢酶的活性。结果显示,当氨和乳酸的添加浓度分别为2.5和10 mmol/L时,对细胞的生长产生弱抑制作用;随着氨和乳酸添加浓度的增加,细胞生长缓慢,营养物质消耗量降低,琥珀酸脱氢酶活性降低;在氨和乳酸添加浓度分别达到5和20 mmol/L时,细胞生长代谢受到严重的抑制,琥珀酸脱氢酶活性在整个培养过程中显著低于对照组。因此,培养液中氨和乳酸积累到一定浓度会抑制BHK-21细胞生长,影响细胞内琥珀酸脱氢酶的活性。     

激流式生物反应器制备猪瘟高效细胞苗

在应用激流式生物反应器培养猪瘟病毒(CSFV)试验中,通过提升单位体积的细胞数量可以有效地提升抗原的效价。二种工艺从单位体积细胞数上比较,转瓶培养细胞数可达到2.5×10~5个/mL,反应器是1.5×10~6个/mL,反应器培养的细胞数是转瓶的6倍;从病毒滴度方面相比,转瓶制备的猪瘟抗原效价最高可达到40万RID/mL,反应器可达到60万RID/mL,反应器比转瓶培养的抗原效价提升50%。     

应用生物反应器培养猪传染性胃肠炎病毒

为了大规模生产猪传染性胃肠炎病毒抗原,试验采用生物反应器及微载体进行ST细胞的培养,待微载体上的ST细胞长满至单层后接种猪传染性胃肠炎病毒(TGEV).共使用生物反应器培养3批TGEV抗原,每批培养过程中分别调节初始细胞密度至2.14×106个/mL、1.83×106个/mL和2.02×106个/mL,微载体浓度为3g/L、6 g/L和9 g/L.结果表明应用生物反应器及微载体培养得到抗原的病毒含量均达到108.0 TCID50/mL,明显高于转瓶培养的病毒含量.     

草鱼出血病细胞培养灭活疫苗生产工艺的比较

比较了方瓶静置培养、１０×２００ｍｌ转管培养和细胞生物反应器微载体培养３种方法增殖细胞和病毒的效率,以细胞生物反应器微载体培养法的效率最高,与静置培养法相比较,单位培养液细胞增殖量提高２０～２５倍,病毒增殖量ＴＣＩＤ５０测定增加１．６５对数值,ＬＤ５０测定增加１．４５对数值。经济效益比较,疫苗制备的培养液成本,以细胞生物反应器微载体培养法最低。已研究出以细胞生物反应器微载体培养法增殖细胞和病毒为基本生产工艺的工厂化生产草鱼出血病细胞疫苗工艺流程。     

猪流行性腹泻病毒在微载体培养Vero细胞上的增殖试验

为了探索猪流行性腹泻病毒(PEDV)在微载体培养Vero细胞上的增殖效果,采用2 L生物反应器进行微载体培养Vero细胞和PEDV繁殖,并摸索细胞生长和病毒繁殖的最佳条件,检测病毒滴度,与方瓶培养的病毒滴度进行比较。结果显示:当微载体为5 g,种子细胞数约3.05×107个,采用灌注式培养,Vero细胞经72 h长满单层,细胞数约为3.02×109个,此时用滴度为104.45TCID50/m L的PEDV 1 m L感染Vero细胞,培养96 h,微载体上80%细胞脱落时收毒,培养的PEDV具有较高的病毒滴度。相同病毒在微载体系统与方瓶上进行同步传代,经检测病毒滴度均有提高,但在微载体系统上培养的PEDV最高滴度可达到106.05TCID50/m L,明显高于方瓶培养。本试验为研究PEDV能更好适应Vero细胞,提高PEDV产量提供技术支持。     

ST细胞全悬浮培养的驯化及其培养伪狂犬病毒的工艺研究

将Siat7e基因转染ST细胞,筛选,驯化得到一株可悬浮培养的ST细胞株,此株细胞能够稳定连续传代,适应无血清、高密度培养,最高密度可达6×10⁶/mL,从摇瓶放大至生物反应器,生长稳定;采用驯化的全悬浮ST细胞培养伪狂犬病毒,从接毒时细胞密度、接毒量、收获时间三个方面优化了伪狂犬病毒的培养参数,确定接毒时细胞密度为2.0×10⁶/mL~3.0×10⁶/mL,接毒量为0.1 MOI~1 MOI,收毒时间为接毒后24 h~36 h。经过50 L生物反应器3个批次的工艺验证,培养的病毒含量均不低于109.0TCID50/mL,说明驯化的ST全悬浮细胞适合伪狂犬病毒的培养。     

猪传染性胃肠炎病毒在ST细胞中增殖规律的研究

通过孔板培养系统以及微载体和转瓶培养系统，研究了感染复数(MOI)、病毒感染时间(TOI)和病毒维持液对细胞生长和猪传染性胃肠炎病毒(TGEV)繁殖的影响。结果表明，MOI影响细胞生长速率和单位细胞病毒产量，TOI影响细胞对病毒的敏感程度以及胞内病毒的增殖速率；丰富的维生素、氨基酸等物质有利于病毒效价的提高；采用微载体和生物反应器系统生产TGEV，病毒效价可达11．3lgTCID50／0．2mL,北方瓶培养系统提高约100倍。     

犬细小病毒YA-16-C66株纸片载体培养工艺优化及其与转瓶培养工艺的比较分析

采用微型生物反应器确定纸片载体上F81细胞最佳的接种密度和最佳接毒剂量,在NBS反应器中验证温度对犬细小病毒YA-16-C66株增殖的影响。经过三次重复试验,确定利用NBS生物反应器培养犬细小病毒YA-16-C66株最佳工艺为：采用同步接毒法,培养基为含1%新生牛血清的199溶液,细胞接种密度为1.5×10_⁷cells/g,接毒剂量为0.05 MOI,在pH7.2条件下,37.0℃培养48h后降温到35.0℃继续培养24-48小时,细胞病变达到80%~90%时收获上清液。三批次反应器与转瓶工艺产品比较,结果表明：反应器比转瓶收获液病毒含量高1.1~1.9 lg TCID₅₀/100μL;相同培养面积,反应器所得病毒总量是转瓶所得病毒总量的2.8-18.5倍。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.