南方鲇源豚鼠气单胞菌胞外产物活性与致病性研究

采用琼脂扩散法测定了南方鲇源豚鼠气单胞菌胞外产物酶活性和溶血活性,同时对胞外产物的细胞毒性和其致病性进行了研究。结果显示:南方鲇源豚鼠气单胞菌胞外产物具有蛋白酶、脂酶、明胶酶和脲酶活性,但不具有淀粉酶和卵磷脂酶活性,具有很强的溶血活性和细胞毒性。肌肉注射感染发现,其对南方鲇有强致病性,其LD50为每千克鱼体重0.802 mg;注射后的南方鲇肌肉、心、肝、肾、脾、肠和胃等组织发生了严重组织病理变化,骨骼肌和心肌坏死断裂,炎症细胞浸润;肝脏严重空泡变性;肾小管上皮细胞变性、坏死、间质内大量炎症细胞浸润;脾充血、出血,淋巴细胞减少,胃肠黏膜上皮细胞变性、坏死、脱落。     

狂犬病病毒糖蛋白基因的克隆及其二级结构和B细胞抗原表位预测

对狂犬病病毒CVS株糖蛋白基因进行克隆与测序,推导出相应的氨基酸序列。然后采用Gam-ier-Robson法和Chou-Fasman法预测糖蛋白的二级结构,用Kyte-Doolittle法、Emini法和Jameson-Wolf法分别预测蛋白质的疏水性、表面可能性和抗原指数,并综合分析预测糖蛋白的B细胞抗原表位。结果表明,该蛋白结构中含有少量的α螺旋、较多的β折叠以及较为丰富的转角区域,在序列的121~126、133~137、161~165、191~193、201~204、214~216、221~225、264~267区域或其附近最有可能是B细胞抗原表位的优势区域。     

Mixotrophy in a Local Strain of Nannochloropsis granulata for Renewable High-Value Biomass Production on the West Coast of Sweden

A local strain of Nannochloropsis granulata (Ng) has been reported as the most productive microalgal strain in terms of both biomass yield and lipid content when cultivated in photobioreactors that simulate the light and temperature conditions during the summer on the west coast of Sweden. To further increase the biomass and the biotechnological potential of this strain in these conditions, mixotrophic growth (i.e., the simultaneous use of photosynthesis and respiration) with glycerol as an external carbon source was investigated in this study and compared with phototrophic growth that made use of air enriched with 1–2% CO₂. The addition of either glycerol or CO₂-enriched air stimulated the growth of Ng and theproduction of high-value long-chain polyunsaturated fatty acids (EPA) as well as the carotenoid canthaxanthin. Bioassays in human prostate cell lines indicated the highest antitumoral activity for Ng extracts and fractions from mixotrophic conditions. Metabolomics detected betaine lipids specifically in the bioactive fractions, suggesting their involvement in the observed antitumoral effect. Genes related to autophagy were found to be upregulated by the most bioactive fraction, suggesting a possible therapeutic target against prostate cancer progression. Taken together, our results suggest that the local Ng strain can be cultivated mixotrophically in summer conditions on the west coast of Sweden for the production of high-value biomass containing antiproliferative compounds, carotenoids, and EPA.     

牛体细胞核移植方法研究

研究了牛体细胞核移植过程的去核方法、融合条件等对重构胚发育的影响,旨在探索一种简化的核移植操作程序.结果表明,添加FSH,LH,最高成熟率为81.7%.在电压为2.6 kV/cm时,融合率为93.96%.激活后重构胚在压制的WOW内进行培养,采用半卵法去核的卵裂率和8-细胞发育率分别为61.2%和3.27%,盲切法去核的卵裂率和8-细胞发育率分别是 70.8%和7.56%.     

两种兼用型牛BoLA-DRA*exon2多态性及其与乳房炎的关联分析

利用PCR-SSCP技术,分析了牛主要组织相容性复合物DRA基因外显子2的多态性在236头中国西门塔尔牛、三河牛中的基因型分布及其多态性与乳房炎的关系。结果表明:经χ2独立性检验,发现该多态片段6种基因型在感染乳房炎牛和健康牛之间分布不一致(p<0.01)。在感染乳房炎牛中CC基因型频率最高,在健康牛中BC基因型频率最高。据此推测,CC基因型可能与这两种牛的乳房炎易感性有关,而BC基因型可能与这两种牛的乳房炎抗性有关。     

Protective effect of C1q/tumor necrosis factor-related protein 3 on vascular endothelium in rats with hyperuricemia

AIM To study whether C1q/tumor necrosis factor （TNF）-related protein 3 （CTRP3）protect vascular endothelium in rats with hyperuricemia and its potential mechanisms. METHODS An animal model of hyperuricemia was established by using male SD rats drinking 10% fructose water （n=10）. The rats drinking normal water served as normal controls （n=10）. After 12 weeks, the rats were given a single injection with Ad-CTRP3 or Ad-GFP. The experiment was ended at 14th day after transfection.The serum levels of uric acid and nitric oxide （NO） were evaluated. The serum contents of TNF-α and interleukin-6 （IL-6） were measured by ELISA. HE staining and TUNEL assay were used to assess the morphological changes of intima and apoptosis of endothelial cells in thoracic aorta, respectively. The mRNA levels of endothelial nitric oxide synthase （eNOS）, TNF-α and IL-6 were detected by RT-qPCR. The protein levels of CTRP3 and Toll-like receptor 4 （TLR4） were determined by Western blot. RESULTS Compared with normal control group, the rats with hyperuricemia showed lower CTRP3 and higher TLR4 protein levels in the thoracic aorta （P<0.05）. Hyperuricemic rats had higher serum contents of uric acid, TNF-α and IL-6 （P<0.05）. Also, the intima structure disturbance of thoracic aorta, increased apoptotic rate, higher mRNA levels of TNF-α and IL-6 as well as lower mRNA levels of eNOS were observed （P<0.05）. By contrast, CTRP3 over-expression decreased TLR4 protein levels, reduced inflammatory cytokines, and obviously improved the morphology and function of thoracic aorta in the rats with hyperuricemia. CONCLUSION CTRP3 protect vascular endothelium in rats with hyperuricemia maybe via down-regulation of TLR4- mediated inflammatory signaling pathway.     

Effects of swimming on experimental endometriosis in rats

AIM To evaluate the effect of swimming on experimental endometriosis in rats. METHODS 80 female SD rats were divided into 8 groups, including control group, model group and animals performed light exercise （swimming once a week）, moderate exercise （swimming 3 times a week）, and intense exercise （swimming 5 times a week） before or after endometriosis induction,10 rats in each group. The mRNA and protein expressions of fatty acid synthase （FAS）, matrix metalloproteinase 9 （MMP9） and proliferating cell nuclear antigen （PCNA） in endometrium of rats were detected. RESULTS The swimming before the induction of the edometriosis lesions did not prove to have aprophylactic role against endometriosis, whereas the swimming after induction of the lesions had a beneficial effect regardless of frequency, with a greater reduction in the groups practicing moderate and intense activity （P<0.05）, an increase in FAS levels and a decrease in MMP9 and PCNA levels were also observed （P<0.05）. CONCLUSION Swimming after induction of the edometriosis is beneficial for the treatment of endometriosis, the mechanism may be related to the expression of FAS, MMP9 and PCNA protein.     

草鱼三元病原菌融合子的构建及生物学特性

采用细胞融合技术首次将肠型点状产气单胞菌菌株和鱼害粘球菌菌株融合,构建二元融合菌株AM-1,再将AM-1与荧光假单胞菌菌株融合,构建三元融合菌株AM-2。对AM-1和AM-2菌株的形态结构、生理生化特性、致病性、抗原性、抗体效价进行分析。结果表明,AM-1活菌椭圆形,无鞭毛,死菌短杆状,AM-2菌株短杆状,有鞭毛,它们的生理生化性状介于3原始亲本菌株之间;用AM-2菌株对当年健康草鱼种进行人工感染攻毒,被攻毒草鱼种具有烂鳃病、赤皮病及肠炎病的部分症状;AM-2菌株抗原的受免草鱼种对荧光假单胞菌、鱼害粘球菌和肠型点状产气单胞菌菌株的免疫保护率分别达64.90％、68.00％、67.00%,抗体效价最高达1∶256、1∶256、1∶512。测定了AM-1和AM-2菌株及亲本DNA含量并进行了琼脂糖凝胶电泳分析,AM-1和AM-2菌株DNA含量明显高于任一原始亲本。图4表6参23     

单细胞凝胶电泳检测除虫脲光解产物对小鼠肝脏DNA损伤研究

采用单细胞凝胶电泳法对不同浓度除虫脲经紫外光照射后的混合物可能导致小鼠肝脏细胞DNA损伤的作用进行了研究,应用CASP软件分析彗星图像,得出彗星尾部DNA百分含量、彗星尾长、尾距和Olive尾距4个指标.通过SPSS软件分析表明,其光降解混合物导致的彗星拖尾现象与空白组有显著区别,且在一定浓度范围呈现剂量-效应关系,表明不同浓度除虫脲经光降解后其混合物具有一定的致突、致癌性,且毒性随着浓度的降低而减小.