表达鼠精子Cyritestin蛋白的减毒沙门氏菌疫苗株的构建及其鉴定

目的 构建表达鼠精子eyritestin蛋白的可口服减毒沙让氏菌活疫苗株。方法 应用质粒TAZ83／13，将之进行双酶切获得含有成熟cyritestin蛋白cDNA序列的酶切片段。将其插入表达载体yA3149中，构建重组质粒pCFL。将该重组质粒转入鼠沙门氏伤寒杆菌疫苗株X4632和X4550中，以获得重组菌株X4632（pCFL)和X4550（pCFL)。结果 该两种无抗药性的重组菌株在体外营养选择压力下，可较稳定地携带重组质粒传代繁殖。X4550(pCFL)在体内可较稳定地害居于Peyer‘s结，肠系膜淋巴结和脾脏；X4632（pCFL)可较稳定地定居于Peyer‘s结。二者均可表达被抗cyritestin单抗（mAb)识别的重组cyritestin蛋白。口服该疫苗菌株无明显的毒性作用。结论 X4632（pCFL),X4550（pCFL)疫苗株的构建，为研究以cyritestin为靶抗原的精子抗原避孕疫苗打下了基础。     

Connexin26 gene ( GJB2): prevalence of mutations in the Chinese population

The connexin26 gene ( GJB2) has been shown to be responsible for DFNB1 and DFNA3 (Autosomal Recessive Hereditary Nonsyndromic Deafness Locus 1 and Autosomal Dominant Hereditary Nonsyndromic Deafness Locus 3). Two hundred ten independently ascertained Chinese probands with nonsyndromic hearing loss (NSHL) were evaluated for mutations in GJB2, including 43 probands from families with more than one sib with NSHL, likely indicating dominant inheritance, and sporadic cases of NSHL, compatible with recessive inheritance. Of the 210 probands, 43 (20%) were homozygous or heterozygous for mutations in GJB2. Four different mutations were identified: 35delG, 109G-A, 235delC, and 299-300delAT. It was confirmed that GJB2 mutations are an important cause of hearing loss in this population. Of these four mutations, 235delC was the most prevalent at 93%; yet the 35delG mutation, which is the most common GJB2 mutation in Caucasian subjects (Europeans and Americans), was found in low frequency in the present study. It appears from our limited data and reports from other East Asians that 235delC is the most prevalent GJB2 mutation in these populations. GJB2 mutations are consistent with ethnic predilections.     

戊二醛交联甲壳胺膜的制备及其渗透性的研究

本文制备戊二醛交联甲壳胺膜。研究了戊二醛交联对膜的亲水性，结晶性的影响；探讨了交联对肌肝、尿素、尿酸的渗透；测定膜在于干态和湿态下的力学机械性能。     

Reaction of chitosan with genipin and its fluorogenic attributes for potential microcapsule membrane characterization

This study investigates the fluorogenic characteristics of the chitosan-genipin reaction for applications in microencapsulation research. Results showed that the chitosan-genipin reaction generated a colored and fluorescent product, with optimal excitation and emission wavelengths at 369 and 470 nm, respectively. Furthermore, it was found that reaction conditions affected the fluorescence intensity of the product. Mixture at the ratio of 4:1 (chitosan: genipin by weight) fluoresced the most. It also fluoresced stronger if the reaction occurred at higher temperature, with the intensity of 10.4 x 10(5) CPS at 37 degrees C, 5.9 x 10(5) CPS at 20 degrees C, and 2.5 x 10(5) CPS at 4 degrees C. As well, the fluorescence of the mixture developed gradually over time, attaining the emission maxima of 2.9 x 10(5), 7.6 x 10(5), and 10.0 x 10(5) CPS in 1, 6, and 18 h, respectively. Chitosan-coated alginate microcapsules were prepared without prior labeling, to which subsequent genipin treatment was applied in order to examine the potential of using genipin in microcapsule characterization. Chitosan bound to the alginate beads interacted with genipin, from which the resultant fluorescent signals allowed for clear visualization of the chitosan coating under confocal laser scanning microscopy. The relative fluorescence intensity across the chitosan membrane was found to be considerably higher than the controls (175 vs. 50). The membrane thickness measured was 29.2 +/- 7.3 microm. These findings demonstrate a convenient and effective way of characterizing chitosan-based microcapsules using genipin as a fluorogenic marker, a technique that will be useful in microcapsule research and other biomedical applications.     

Reactive Compatibilization of PA6/LDPE Blends with Glycidyl Methacrylate Functionalized Polyolefins

Summary: Blends of polyamide‐6 (PA6) and low density polyethylene (LDPE) were compatibilized by melt mixing with various polyolefins functionalized with glycidyl methacrylate (GMA), i.e., GMA grafted LDPE (LDPE‐g‐GMA), GMA grafted styrene‐ethylene/butylene‐styrene block copolymer (SEBS‐g‐GMA) and ethylene‐co‐glycidyl methacrylate copolymer (E‐GMA). Blends with PA6/LDPE composition ratios of 25/75 and 75/25 wt.‐%/wt.‐% were prepared in a Brabender internal mixer and their properties were evaluated by SEM, rheological measurements and DSC. Morphological investigation by SEM showed a neat improvement of phase dispersion and interfacial adhesion in all compatibilized blends when compared to PA6/LDPE binary blends. The variation of the dispersed phase size was analyzed as a function of blend composition, compatibilizer concentration and GMA content. The emulsification curves of compatibilized blends showed that the equilibrium size of dispersed particles at the saturation concentration of copolymer was lower when PA6 was the major component. The finest dispersion of the LDPE phase (<0.25 μm) was observed in the presence of SEBS‐g‐GMA copolymer. LDPE‐g‐GMA and E‐GMA displayed a similar compatibilizing efficiency. In all cases, the blends with a polyamide matrix presented a marked rise in torque and melt viscosity with increasing compatibilizer content. These effects were accounted for by a reaction between the epoxide groups of LDPE‐g‐GMA and the carboxyl/amine end‐groups of PA6, leading to the formation of an interchain graft copolymer. The phase transition processes of PA6 in the blends were influenced by the compatibilizer content and the interfacial interactions between the polymer components, suggesting a different role for the compatibilizer at the PA6/LDPE interface.

SEM micrograph of PA6/LDPE 25/75 blend compatibilized with 2.5 phr SEBS‐g‐GMA.     

Effects of ammonium metavanadate treatment upon macrophage glutathione redox cycle activity, superoxide production, and intracellular glutathione status

Female B6C3F1 mice were given intraperitoneal injections of ammonium metavanadate (2.5 or 10 mg V/Kg), ammonium chloride, or sodium phosphate buffer every 3 days for 6 weeks. Resident peritoneal macrophages were harvested, lysed by freeze-thawing, and the resulting cytolysate was assayed for total protein content and enzyme activities of glutathione reductase, glutathione peroxidase, and glucose-6-phosphate dehydrogenase. In addition, peritoneal macrophages were assayed for superoxide production using nitroblue tetrazolium reduction, as well as for intracellular levels of oxidized and reduced glutathione. Exposure of mice to vanadium resulted in a dose-trend depression in the three macrophage enzyme activities as compared with the controls. Vanadium treatment resulted in a similar decrease in the production of superoxide anion, and an increase in levels of oxidized glutathione; however, the total glutathione pool (reduced plus oxidized forms) was not affected.     

Immunochemical data suggesting a pattern for the evolution of human placental alkaline phosphatase

Hyperimmune absorbed rabbit antisera which were reactive with epitopes specific for individual variants of human placental alkaline phosphatase were tested for their reactivity with primate placental alkaline phosphatases. Using the three epitope-specific reactivities defined previously, we found that: epitope I is present in the S-, D- and I-variants of human placental phosphatase, and in the chimpanzee and pygmy chimpanzee placentae; epitope II is present in the F- and 17-variants, and in the Nagao isoenzyme of human placental alkaline phosphatase, and in some orangutan placentae and all spider monkey placentae tested; epitope III is present in the F- and 17-variants, and the Nagao isoenzyme of human placental alkaline phosphatase, and in all the spider monkey placentae and the single squirrel monkey placenta examined. The binding assay was complemented by a competitive radioimmunoassay, which confirmed that the spider monkey placental samples were binding to the same antibody population which bound the human enzymes. The presence of epitopes characteristic of rare human placental phosphatase variants in these remote primate relatives suggests that the rare variants in the current human population have been present during the entire course of evolution. The presence of both epitopes characteristic of the Nagao isoenzyme in spider monkeys suggests that this variant isoenzyme is closely related to the enzyme present in the primate placenta at the time of species divergence (humans and New World monkeys). A hypothetical scheme for this divergence is proposed.     

IL-15真核表达质粒的构建及对乙肝疫苗诱导的体液免疫应答的影响

目的 研究两种不同的IL-15真核表达质粒对乙肝蛋白疫苗诱导的免疫应答的影响。方法：构建IL-15真核表达质粒(简称pIL-15)和含有IL-12信号肽的IL-15真核表达质粒(简称pIL-2s-15)，CTLL-2细胞增殖实验验证两种质粒真核表达产物的生物学活性。将这两种质粒分别与HBsAg共免疫BALB／C小鼠，用ELISA法检测小鼠血清抗-HBs IgG及IgGl、IgG2a亚类的效价。结果：与HBsAg蛋白疫苗共免疫时，pIL-15可使HBsAg诱导的抗-HBsIgG效价升高，显著高于载体pcDNA3．1与HB—sAg共免疫对照组，pIL-2s-15对HBsAg诱导抗-HBsIgC效价没有明显影响。与HBsAg pcDNA3．1组相比，HBsAg pIL-2s-15组和HBsAg pIL-15组诱生的抗HBsIgG2a亚类均升高，但前者IgG2a／IgG1比值最高，与HBsAg pcDNA3．1组相比差别有显著性；HBsAg pIL-15组IgG2a／IgG1比值与HBsAg pcDNA3．1组相比差别无显著性。结论 pIL-15真核表达质粒可增强蛋白疫苗诱导的体液免疫应答，pIL-2s-15真核表达质粒则主要使免疫应答趋向Th1型。     

卡介苗对豚鼠实验性哮喘的预防性治疗作用

目的:观察卡介苗(BCG)对哮喘豚鼠的预防治疗作用。方法:采用31只豚鼠,分为3组进行处理,分别为对照组、卵蛋白(OVA)致敏组和BCG处理组。用OVA(Ⅲ级)致敏豚鼠复制豚鼠哮喘模型。结果:本模型采用10%的OVA致敏,1%的OVA激发,所有动物都表现有不同程度的过敏反应症状。实验动物在接受BCG注射后,表现为以下特点:一是外周血淋巴细胞和单核细胞增加;二是BALF中细胞分类的变化,支气管肺泡灌洗液(BALF)中以淋巴细胞的增加最为明显。 经过OVA致敏的动物BALF和肺组织中嗜酸性粒细胞(EOS)明显增加,BCG不同程度地降低肺组织EOS的气道浸润及减轻OVA致敏豚鼠的气道反应。结论:[HTSS]使用本实验体系BCG可以减轻实验性哮喘的气道炎症反应。