Chemerin fragments show different effects on systemic blood pressure dependent on carboxyl-terminal cleavage site

Chemerin is an adipocytokine whose concentration in blood correlates positively with blood pressure (BP). We have recently revealed that acute intracerebroventricular (i.c.v.) injection of chemerin-9, an active fragment of human chemerin, increased systemic BP in normal Wistar rats, suggesting that chemerin is involved in the central nervous control of peripheral BP. After secreted as an inactive form as prochemerin, a mature form of active chemerin is produced through the cleavage of its carboxyl (C)-terminus by proteases. Although the activity of cleaved products of chemerin has been examined in vitro, in vivo effects remained to be elusive. In order to explore them, we performed acute i.c.v. injection of mouse chemerin-9 (mChemerin-9; 148F-156S), mouse chemerin-8 (mChemerin-8; 148F-155F), and mouse chemerin-7 (mChemerin-7; 148F-154A) into Wistar rats, and examined the effects on systemic BP. After chemerin fragment (1–30 nmol/head, i.c.v.) was cumulatively administered, systemic BP was measured by a cannulation method under an isoflurane anesthesia. mChemerin-9 but not mChemerin-8 and -7 induced a pressor response, which was concentration-dependent. In conclusion, we for the first time demonstrated that mChemerin-9 that corresponds to the C-terminal nine amino acids of active mouse chemerin156S increased systemic BP in rats, and also that chemerin fragments showed different effects on systemic BP dependent on how their C-terminus was cleaved.     

母猪热应激敏感指标体系的研究进展

母猪由于其皮下脂肪厚、汗腺不发达等特点,在高温环境下容易发生热应激。有研究表明:热应激会改变其生理状态和血液生化成分等,降低母猪繁殖力,造成严重的经济损失。然而,目前针对母猪热应激敏感指标的研究总体较粗略、评价体系不全面;而且,母猪的耐热性受遗传、年龄和日粮等多种因素的影响,使得准确评价母猪热应激状态比较困难,成为制约母猪适宜环境参数研究的重要因素。笔者在系统总结母猪热应激研究的基础上,从表型、生理、生化、分子等不同层次探讨了相关指标对热应激的敏感程度及其作为母猪热应激评价指标的可行性,以期为生产中母猪热应激诊断及环境参数的优化奠定基础。总结发现:母猪热应激敏感指标有表皮温度、呼吸频率、直肠温度、血液和肝脏热休克蛋白70(HSP70)等;比较敏感的指标有:血中皮质醇(COR)、天门冬氨酸转移酶(AST)、丙氨酸转移酶(ALT)、肌酸激酶(CK)和乳酸脱氢酶(LDH)。其他指标如血清蛋白、血糖、血液免疫细胞、K+、Na+等随母猪热应激也有所变化,可作为辅助参考指标。其中,表皮温度、呼吸频率、直肠温度和HSP70水平可作为评价母猪长期热应激的指标。此外,尽管母猪热应激造成的行为变化相对滞后...     

Antioxidant Efficacy of a Spirulina Liquid Extract on Oxidative Stress Status and Metabolic Disturbances in Subjects with Metabolic Syndrome

Lipid peroxidation is associated with the development of some pathologies, such as cardiovascular diseases. Reduction in oxidative stress by antioxidants, such as Arthrospira (formely Spirulina), helps improving this redox imbalance. The aim of the study was to evaluate the effect of the Arthrospira liquid extract “Spirulysat^®” on oxidative markers—in particular, oxidized LDL (oxLDL)/total LDL cholesterol—and isoprostanes and to investigate its impact on lipid and glucose metabolism in the metabolic syndrome subject. A controlled, randomised, double-blind design was conducted in 40 subjects aged 18 to 65 years with metabolic syndrome after a daily intake of Spirulysat^® or placebo for twelve weeks. Blood and urinary samples were collected at three visits (V1, V2, V3) in the two groups for parameters determination. Although the Spirulysat^® group showed a decrease at all visits of the oxLDL/total cholesterol ratio, there was no significant difference compared to the placebo (p = 0.36). The urinary isoprostanes concentration in the Spirulysat^® group was reduced (p = 0.014) at V3. Plasma triglycerides decreased at V3 (p = 0.003) and HDL-cholesterol increased (p = 0.031) at all visits with Spirulysat^®. In conclusion, Spirulysat^® did not change the oxidized LDL (oxLDL)/LDL ratio but decreased the urinary isoprostanes, plasma triglycerides and increased HDL cholesterol, suggesting a beneficial effect on metabolic syndrome.     

芝麻对大剂量维生素D3致大鼠动脉钙化的治疗作用

目的研究芝麻对大鼠血管钙化的治疗作用。方法40只SD雌性大鼠随机分成正常组、VitD3模型组、辛伐他汀组和芝麻组4组,每组均为10只。用大剂量VitD3灌胃的方式造成大鼠血管钙化模型,同时分别用辛伐他汀和芝麻进行治疗,比较VitD3模型组和各治疗组大鼠主动脉血管钙化程度及其血脂水平。结果芝麻组的主动脉弓血管钙化面积为(1.29±0.20)%,腹主动脉血管血钙含量(14.7±6.7)μmol/g,明显低于VitD3模型组(60.7±16.7)%和(22.8±8.8)μmol/g(均P<0.01)。VitD3模型组大鼠的血清总胆固醇(TC)含量和低密度脂蛋白胆固醇(LDL-C)含量明显升高,血清甘油三酯(TG)及高密度脂蛋白胆固醇(HDL-C)含量明显降低(P<0.05);与模型组比较,辛伐他汀组的TC含量无明显差异,芝麻组的TC含量则明显下降(P<0.05);辛伐他汀组的HDL-C明显升高(P<0.05),芝麻组的HDL-C含量则无明显变化。结论芝麻对VitD3造成的大鼠血管钙化具有预防治疗作用。     

Molecular detection of Fusarium solani f. sp. glycines in soybean roots and soil

A polymerase chain reaction (PCR)-based method was developed to detect DNA of Fusarium solani f. sp. glycines , the cause of soybean sudden death syndrome. Two pairs of primers, Fsg1/Fsg2 designed from the mitochondrial small subunit ribosomal RNA gene, and FsgEF1/FsgEF2 designed from the translation elongation factor 1-α gene, produced PCR products of 438 and 237 bp, respectively. Primer specificity was tested with DNA from 82 F. solani f. sp. glycines , 55 F. solani non-SDS isolates, 43 isolates of 17 soybean fungal pathogens and the oomycete Phytophthora sojae , and soybean. The sensitivity of primer Fsg1/Fsg2 was 10 pg while that of FsgEF1/FsgEF2 was 1 ng when using F. solani f. sp. glycines total genomic DNA or down to 10³ macroconidia g⁻¹ soil. Nested PCR increased the sensitivity of the PCR assay 1000-fold to 10 fg using primers Fsg1/Fsg2, and 1 pg using primers FsgEF1/FsgEF2. F. solani f. sp. glycines DNA was detected in field-grown soybean roots and soil by PCR using either single pairs of primers or the combination of two pairs of primers. The occurrence of F. solani f. sp. glycines was determined using nested PCR for 47 soil samples collected from soybean fields in 20 counties of Illinois in 1999. F. solani f. sp. glycines was detected in soil samples from all five Illinois Agricultural Statistic Districts including 100, 89, 50, 92 and 50% of the samples from East, Central, North-east and West Districts, respectively.     

Effects of astragaloside on the levels of sex hormone and oxidative stress injury in rats with polycystic ovary syndrome

AIM To investigate the effects of astragaloside on the levels of sex hormone and oxidative stress in rats with polycystic ovary syndrome （PCOS）. METHODS Female SD rats （n=60） were randomly divided into normal control group, model group, Diane-35 （0.339 2 mg/kg） group, low dose astragaloside （12.5 mg/kg） group and high dose astragaloside （50 mg/kg） group, with 12 rats in each group. The PCOS model was induced by letrozole （1 mg/kg）, which was administered by gavage once a day for 3 weeks. After administration, the estrus cycle of the rats was observed by vaginal smear, and the ovarian index was calculated. HE staining was used to observe the histopathological changes of the ovaries. Serum levels of the sex hormones testosterone （T）, estradiol （E₂）, luteinizing hormone （LH） and follicle-stimulating hormone （FSH） were measured by ELISA. The levels of superoxide dismutase （SOD）, malondialdehyde （MDA） and glutathione peroxidase （GSH-Px） in serum and ovarian tissue were detected by colorimetry, and the protein levels of steroidogenetic acute regulatory protein （StAR） and apoptosis-related proteins cleaved caspase-3, Bax and Bcl-2 in ovarian tissue were detected by Western blot. RESULT Compared with control group, the oestrous cycle of the rats in model group was disorder, and the ovarian index was increased, ovary was polycystic. The serum levels of T, LH and MDAwere significantly increased （P<0.05）, while the contents of E2, FSH and the activities of GSH-Px and SOD were significantly decreased （P<0.05）. The levels of MDA, StAR, cleaved caspase-3 and Bax proteins in ovarian tissue were significantly up-regulated （P<0.05）. GSH-Px and SOD activities and Bcl-2 protein levels were significantly down-regulated （P<0.05）. CONCLUSION Astragalosideeffectively balances the levels of sex hormone in PCOS rats and relieves the oxidative stress injury, the mechanism may be related to the inhibition of StAR expression.     

河北猪繁殖与呼吸综合征病毒HB-3(cz)株N基因变异分析及原核表达

为了给河北地区预防和控制猪繁殖与呼吸综合征提供理论数据。应用RT-PCR方法特异性扩增HB-3(cz)株的ORF7(N)基因片段,将扩增片段克隆入pMD-T载体后测序,应用DNAstar分析软件对序列进行分析,并与GenBank中发表的PRRSV毒株序列进行比较。结果显示:HB-3(cz)株与高热病毒株JXA1、HUB2等及传统河北分离株HB-1(sh)氨基酸同源性高达97.6%,属美洲型毒株。将目的片段克隆入原核表达载体pGEX-6P-1,重组质粒pGEX-N转化大肠杆菌BL21(DE3),在IPTG诱导下成功获得表达,经Western-blot-ting分析表明:表达的融合蛋白分子量约为39.5 kDa,能与PRRSV的阳性血清发生特异性反应,为PRRSV血清学诊断方法的建立奠定了基础。     

猪瘟病毒、猪繁殖与呼吸障碍综合征病毒和乙型脑炎病毒多重RT-PCR检测方法的建立

根据猪瘟病毒(CSFV)的E2基因保守序列、猪繁殖与呼吸障碍综合征病毒(PRRSV)的ORF7基因及部分ORF6和3-UTR基因序列和猪乙型脑炎病毒(JEV)的E基因保守序列,设计了3对引物,扩增大小分别为288 bp、430 bp和1 015 bp目的片段.以纯培养病毒抽提RNA,制备cDNA模板,利用3对引物,通过条件的优化,建立了同时检测这3种病毒的多重RT-PCR.CSFV、PRRSV和JEV的RNA最小检出量分别为0.270 ng、0.049 ng、0.067 ng,其它的RNA病毒如TGEV以及DNA病毒如PPV、PrV、PCV-2检测结果为阴性.以β-actin为对照,利用本方法检测了174份临床样品(血清、肺脏和胎儿),其结果为:PRRSV、CSFV和JEV的阳性率分别为30.4%、4.6%和1.7%;CSFV和PRRSV混合感染阳性率为1.7%.同时对临床样品中CSFV、JEV和PRRSV阳性PCR产物进行测序分析,发现CSFV、PRRSV和JEV的PCR产物序列和NCBI数据库中目标基因的同源性分别为92%、90%和89%,这证实了多重PCR的阳性结果为上述3种病毒.结果证明,所建立的多重RT-PCR可用于临床检测.     

猪繁殖与呼吸综合征诊断技术研究进展

猪繁殖与呼吸综合征（PRRS）是猪群中的一种免疫抑制性传染病,是严重危害我国养猪业的主要疫病之一,应用各种诊断技术对该病做出准确的诊断是预防和控制该病的前提。PRRS诊断技术包括检测病毒、检测血清抗体技术及分型诊断,涉及的技术和方法包括病毒分离、免疫组化、RT-PCR、间接免疫荧光试验、免疫过氧化物酶单层细胞试验、酶联免疫吸附试验和基因芯片技术等。每种诊断技术都有其各自的优势和局限性,应根据研究目的及工作条件等综合情况予以选择,文章就各种诊断技术的原理、方法及特点进行了概述和比较,并对今后的应用前景和发展趋势进行了展望。     

猪皮炎肾病综合征组织病理学和PCR诊断

应用病理学和PCR方法,对浙江某猪场送检的疑似猪皮炎肾病综合征（PDNS）病猪进行诊断。结果发现肾脏呈现纤维蛋白性肾小球肾炎变化,真皮及皮下血管表现为坏死性脉管炎,淋巴组织中大量淋巴细胞缺失、多核巨细胞浸润,PCR扩增产物显示猪圆环病毒2型（PCV-2）阳性。结果表明,该猪场感染了PCV-2,并表现为PDNS的病理特征。