SPF鸡新引种群的饲养与保种研究

随着中国养禽业的发展和疫苗生产的不断扩大,无特定病原(SPF)鸡蛋的需求量也随着增加。为了提高生产力和市场竞争力,1995年初北京实验动物研究中心从美国引入了SPF种蛋。其中母系1800枚,父系200枚。引人种蛋在一个完全独立的屏障系统中孵化和饲养,经两次微生物监测完全符合引种标准后解除隔离。新种群按照预先设计的保种方案,经几个世代的保种繁育,各项生产性能表现出高于或等于引入种群的生产性能。特别是产蛋率和受精率从引人种群的83老和93老提高到85老和98老。与中心原有种群(澳大利亚)相比,各项生产性能有了大幅度提高,经济效益明显提高。     

非霍奇金淋巴瘤细胞DNA含量测定的临床意义

研究非霍奇金淋巴瘤(NHL)中DNA含量和S期细胞比例(SPF)在非霍奇金淋巴瘤诊断和治疗中的意义。方法:35例NHL患者(NHL组)和10例淋巴结反应性增生患者(对照组)的新鲜淋巴组织,应用流式细胞技术检测其中DNA含量,并计算SPF。结果:35例NHL中异倍体出现率为37.10%(13/35)。10例反应性增生淋巴结组织中无异倍体出现。NHL组SPF均值为22.39%,对照组为9.88%(P<0.01)。NHL患者中低度恶性、中度恶性及高度恶性的SPF均值分别为9.10%、23.48%及29.16%。化疗有效者(完全缓解加部分缓解)SPF为25.63%,无效者为14.23%(P<0.05)。结果表明NHL中SPF的表达有随着恶性程度的增高而增加的趋势。肿瘤表现异倍体或高SPF者近期疗效好。结论:异倍体或高SPF有助于NHL的诊断并与疗效有关。     

SPF级实验动物设施改建工艺设计探讨

目的对SPF级实验动物设施的建立和管理进行初步探讨。对象把武汉生物研究所的清洁级实验动物设施改建为SPF级设施。设计原则SPF级实验动物生产饲养和实验饲养设施条件配套,人、物、动物、空气流的工艺流程合理。结果改造后的SPF级实验动物设施的环境参数符合国标要求,已取得相应的许可证。     

DNA含量及S期细胞比值和胃癌生物学特性的关系

研究ＤＮＡ含量及ＳＰＦ值与胃癌临床病理指标及ＰＣＮＡ表达的关系。方法：应用流式细胞术测定７２例胃癌新鲜组织及３１例良性胃粘膜病变新鲜组织的ＤＮＡ含量ＳＰＦ值,并采用免疫组织化学方法检测６６例胃癌石蜡切片的ＰＣＮＡＬＩ,并结合临床资料分析其临床意义。结果胃癌的ＤＩ（１．２１）及异倍体检出率（４４．４４％）,明显高于良性胃粘现变组（分别为１．０５和９．６８％）吕患者中异倍体组的ＳＰＦ值（２２．７４％）     

肾母细胞瘤组织中DNA倍体、SPF、增殖细胞指数的测定

目的：探讨肾母细胞瘤组织中DNA倍体、SPF、增殖细胞指数(PI)与临床分期及病理分级间的关系。方法：应用流式细胞仪(FCM)测定35例肾母细胞瘤标本的DNA倍体、SPF、PI值,并与正常肾组织比较。结果：与正常肾组织相比,I～Ⅱ期与Ⅲ～Ⅳ期肿瘤的异倍体率、SPF、PI值均升高,但肿瘤各临床分期I～Ⅱ期与Ⅲ～Ⅳ期之间,及病理FH型与UH型之间差异无统计学意义。结论：测定肾母细胞瘤的DNA倍体、SPF、PI值能了解其某些分子生物学特性,从分子水平上了解其增殖活性,对肿瘤的诊断及评估预后有一定的意义。     

Alternative evaluation method in vitro for the water-resistant effect of sunscreen products

Background/purpose: Sunscreen products today represent a trend of providing not only simple sun protection factor (SPF)/protection of UVA (PFA) but also other additional benefits. For example, as popularized by seasonless use of sunscreens, the special function of water resistance or sand proof is added to sunscreens as well as for leisure. Because a human in vivo test is time consuming and expensive, a screening process has been tried using an accurate in vitro system. In this study, we suggest the development of an in vitro test that can predict the result of in vivo water resistance of sunscreens. Methods: Water resistance is presented as a comparison of initial SPF and water‐exposed SPF by immersion and washing. In order to be comparable with the in vivo test, water immersion and flow were defined as the basic statements. Also, substrate, revolutions per minute (r.p.m.) – rotative velocity – of propeller inducing water flow, and time of immersion were defined as controlled factors. Considering the strength, separation of test material and adhesive texture, a PMMA plate was selected as suitable among commercial substrates: Transpore tape?, VITRO SKIN, and PMMA plate. Also, when the PMMA plate was adhered on the wall of a water bath, the water turbulence of the rotational propeller alone was not strong enough to wash off the test material from the substrate. Therefore, PMMA plates were fixed on the axis. In this experiment, the most important thing is whether this in vitro system can predict correctly. Hence, we tried to match the in vitro water resistance following from our control factors and water resistance value of the in vivo test. Results: We found the immersion time and r.p.m. of controlled factors to obtain the target water resistance using design of experiment, MiniTab statistical package. Response optimization yielded the optimal in vitro conditions of 150 r.p.m./60 min. The repeatability and reproducibility of this in vitro system were also good in validation studies. Conclusions: This study enables to modify an in vivo water resistance test and predict the result of in vivo water resistance by the manufacture of effective equipment and choosing a suitable substrate. Compared with in vivo results, our in vitro system is more time and cost effective, and provides reliable results.     

血链球菌和牙龈卟啉单胞菌在SPF大鼠口腔中的相互作用

目的：研究从ＳＰＦ大鼠口腔中分离的内源性血链球菌是否可以阻止或减少牙周可疑致病菌牙龈卟啉单胞菌Ｐ．ｇ３８１在口腔的生长和定植。方法：选用１０只ＳＰＦ大鼠分作２组，强力霉素口腔清扫７ｄ以后分别接种内源性血链球菌和Ｐ．ｇ３８１，二者均获稳定定植，接着选用３０只ＳＰＦ大鼠经强力霉素口腔清扫后随机分作Ａ￣Ｆ６组，其中Ａ、Ｂ两组 接种Ｐ．ｇ３８１５ｄ，Ｃ，Ｅ两组先接咎血链球菌５ｄ，然后Ａ组再接种血链球菌５ｄ     

螺旋藻制剂调节实验性肠菌群失调症药效学研究

本研究通过对不同浓度螺旋藻制剂进行药效学试验，验证其调节实验性肠菌群失调症，治疗抗生素相关性腹泻的效果。结果表明：1）治疗前各组100％出现中，重复腹泻；治疗后第6天，转为正常－－轻度腹泻者，高剂量组和中剂量为100％，低剂量组为80％。2）菌群分析结果显示，螺旋藻低剂量组双歧杆菌和肠肝菌数量水平早期均显著高于两对照组（P＜0．05），中剂量和高剂量组生理菌数量增加水平基本相同；较自然恢复组增加非常显著（P＜0．01），较生理盐水组增加显著或非常显著（P＜0．05或P＜0．010。实验提示，螺旋藻可显著缓解肠菌群失调症模型小鼠的腹泻症状，但有一定剂量依赖性。中剂量和高剂量均可迅速缓解模型小鼠腹泻症状，纠正其肠道菌群紊乱，两者间的治疗效果无显著差别。     

Safety assessment of transgenic Bacillus thuringiensis with VIP insecticidal protein gene by feeding studies.

The aim of this study was to evaluate the toxicology safety of a genetically modified (GM) Bacillus thuringiensis with vegetative insecticidal protein (VIP) gene. Acute and subacute toxicity studies by using its powder preparation were conducted in Wistar rats. The result of the acute study showed the no-observable-adverse-effect level (NOAEL) of this GM B. thuringiensis powder preparation was greater than 5000 mg/kg body weight (BW). In the subacute study, the data analysis of body weight gain, food and water consumptions, clinical observations, haematology, serum biochemistry, organ weight ratios and histopathological findings did not show significant differences between control and treated groups. These results proved the NOAEL of this GM B. thuringiensis powder preparation in subacute test was greater than 5000 mg/kg BW. Since both the acute and subacute oral toxicity were not detected at the highest dose recommended by OECD guidelines, this GM B. thuringiensis could be generally regarded as safe for use in bio-pesticide industry.     

Tumor targeting of vincristine by mBAFF-modified PEG liposomes in B lymphoma cells

Malignant hematologic diseases are highly malignant and refractory to conventional therapies. Ligand-mediated targeting of liposomal anticancer drugs to surface receptors expressed on malignant B cells can be an effective strategy for treating B-cell malignancies. BAFF plays an important role in the maintenance of normal B-cell development and homeostasis and the expression of its receptors is significantly increased in numerous B-cell malignancies. mBAFF (a soluble BAFF mutant with amino acid 217–224 being replaced by two glycine residues) may be used as a competitive inhibitor for BAFF to treat relevant malignant hematologic diseases. It may also hold promise as a novel ligand for targeted anticancer therapy. In this study, we show that liposomes that are sterically stabilized by PEG and surface decorated with mBAFF exhibited strong affinity and specificity to cultured human Raji B lymphoma cells. Vincristine formulated in the targeted liposomes showed significantly higher levels of cytotoxicity towards Raji cells than the nontargeted liposomal drug. Therapeutic experiments in SCID mice implanted with Raji cells showed significantly prolonged survival time with targeted liposomal vincristine compared to either free VCR or vincristine formulated in nontargeted liposomes. These studies suggest the potential of the mBAFF-modified liposomal drugs in targeted therapy of B-cell malignancies.