柳州市蔬菜质量安全监测体系现状与完善对策

蔬菜质量安全关系到人民的身体健康和社会是否能和谐发展,因此蔬菜质量安全监测体系的建设越来越受到人们的关注。通过对柳州市蔬菜质量安全的市—县—乡镇—村(基地)四级监测体系现状进行深入调查,剖析了其运行过程中存在的弊端以及不足之处,并相应的提出4项完善对策以进一步完善监测体系,更加充分发挥其保障市民餐桌安全的职能。     

Establishment of experimental autoimmune encephalomyelitis model in mice induced by MOG and its effect on CD4+CD25+ T cells

AIM: To investigate the feasibility of inducing experimental autoimmune encephalomyelitis(EAE)model in C57BL/6 mice by TrxA-extracellular immunoglobulin domain of MOG(MOGIgd-TrxA)fusion protein produced by molecular cloning in our laboratory. Also to investigate the role of CD4+CD25+ T cells in the pathogenesis of EAE. METHODS: (1)The MOGIgd-TrxA fusion protein was induced and produced by molecular cloning and purified by metal chelate affinity chromatography and concentrated through ultrafiltration. The concentration of the protein was measured by Bradford method at last. (2)Animal experiment: C57BL/6 mice(12 mice in each group)were used. The mice in group MOG were immunized with MOGIgd -TrxA fusion protein. The mice in group GPSCH were received emulsion of spinal cord homogenate of guinea pigs(GPSCH), and mice in group TrxA or normal control group(group NC)were received the same volume emulsion of TrxA or saline/adjuvant, respectively. Clinical scores and histopathology were measured to value the models quality. (3)The percentages of CD4+CD25+ regulatory T cells in EAE mice were tested through flow cytometric analysis. RESULTS: (1)The purity of purified MOGIgd -TrxA fusion protein was about 98%, and its concentration was 2.3 g/L. (2)No significant difference between group MOG and group GPSCH in the clinical score was observed(P>0.05). Histologic sections of the brain and spinal cord taken from affected animals in both groups showed pathological change of different level throughout the central nervous system(CNS). (3)Percentages of CD4+CD25+ T cells in group MOG and group GPSCH were(4.71±1.61)%and(1.44±0.65)%,respectively, both of which were significantly lower than those in group NC(9.22±1.24)%and TrxA group(8.97±1.20)％(P<0.01). CONCLUSION: (1)The animal model of EAE in C57BL/6 mice induced by MOGIgd fusion protein produced through molecular cloning in our laboratory is stable and with high incidence. Thus, the author finds a good way to study the immune mechanisms of MS further and to search for the effective treatments as well. (2)The reduction of CD4+CD25+ T cells in EAE mice may have some relationship with the clinic.     

Application of anti-CD20 antibody in hematopoietic stem cell transplantation for sensitized recipients

AIM: To find a strategy for enhancing engraftment of hematopoietic stem cell in sensitized recipients and to study the effects of anti-CD20 antibody in hematopoietic stem cell transplantation. METHODS: BALB/c mice were sensitized by transfusions of allogeneic spleen cells on 14 d and 7 d. Anti-CD20 antibody (2 mg/mouse) was intravenously injected into sensitized recipients on 11 d. The recipients were used as experimental group, while RPMI-1640 medium (0.2 mL/mouse) was used as control. The sera and splenocytes obtained from the recipients were tested for donor reactive antibody and CD19+ B cells on 0 d. In addition, the recipients were transplanted with 1×107 C57BL/6 bone marrow cells after lethal irradiation on 0 d. The survival rates were observed and blood counts were studied post transplantation. RESULTS: The cytotoxic index in the experimental group and control group were (37.00±3.46)% and (51.80±3.49)%, respectively, and the differences were significant (P<0.01). The percentages of CD19+ B cells in experimental group and control group were (17.32±3.02)% and (34.26±2.87)%, respectively, and the differences were significant (P<0.01). All the recipients in both experimental group and control group died about 14 d post transplantation. The median time was 13 d and 11 d in experimental group and control group, respectively, and no significant difference was found between these two groups (P>0.05). Moreover, a rapid disappearance was observed in the white blood counts, hemoglobin, and platelet of dying animals, indicating the animals died from hematopoietic failure. CONCLUSION: Anti-CD20 antibody is able to deplete B cells and reduce the level of antibody in sensitized recipients, but it can’t enhance the engraftment of allogeneic hematopoietic stem cells in the sensitized recipients.     

南口农场机采棉作业的组织管理

<正>1机具配备南口农场2000年购进凯斯2555型采棉机5台,2008年购进凯斯CPX620型采棉机2台,2009年购进凯斯CPX620型采棉机3台、(其中自带打膜机1台),购进凯斯自走"爱国者"3315型喷脱叶剂机械1台,国产自走喷脱叶剂机械3台。2009年购     

糯玉米opaque2基因近等基因系的创制

opaque2基因能够提高糯玉米赖氨酸、色氨酸等必需氨基酸的含量。用2种优质蛋白玉米(QPM)CA339和鲁2548自交系作为opaque2基因供体,25个品质较好的糯玉米自交系作为受体,利用回交技术和SSR分子标记辅助选择育种,创制糯玉米opaque2近等基因系。分子标记结果表明,不同受体以及两种供体间都存在多态性。5套创制成功的opaque2近等基因系的赖氨酸含量比其轮回亲本分别提高了59.0%、52.7%、48.5%、46.3%和61.9%,分别由0.308%、0.313%、0.309%、0.341%、0.323%提高到0.489%、0.478%、0.458%、0.498%、0.522%。本研究表明,可以利用此方法通过向不同遗传背景的多种受体导入opaque2,选取赖氨酸含量提高较大、透明表型的近等基因系,提高糯玉米的营养价值和经济价值。     

江淮大豆育种种质苗期耐旱性鉴定

江淮地区是我国大豆重要产区,季节性干旱时有发生,发掘适合本地区种植的耐旱新材料十分必要。选用210份江淮大豆育成新品种(系)及其部分亲本为材料,于2015和2016两年进行旱棚盆栽试验,以地上部干重、株高、主根长和根干重4个性状的耐旱系数为指标,通过主成分分析、隶属函数值法和聚类分析对其苗期耐旱性进行综合评价。结果表明:与正常供水相比,干旱胁迫下4个性状均显著降低,其中地上部干重、根干重、株高和主根长平均分别减小54%、42%、39%和15%;方差分析显示各性状在水分处理间和材料间均存在极显著差异,而株高和根干重性状上基因型、水分处理和年份三因子间一级互作和二级互作效应均为极显著。地上部干重与株高、根干重间以及主根长与根干重间的耐旱系数存在显著正相关,反映指标间有内在联系;主成分分析提取的前3个相互独立的主成分的累积贡献率达83.61%,能较好地替代原有4个信息部分重叠的性状;进一步获得耐旱性综合评价D值,结合聚类分析将所有材料分为强耐旱、耐旱、中度耐旱、干旱敏感、干旱强敏感5类。共鉴定出强耐旱材料5份(包括IA2077、YC4H/NN88-31//NN73-935、蒙8108、NN88-48/NN86-4和NN88-48/D76-1609)、耐旱材料57份。来自淮南和淮北地区的强耐旱或耐旱材料分别为27份(占该地区83份材料的32.53%)和19份(占该地区76份材料的25.00%)。所得结果可为大豆耐旱遗传育种提供材料。     

延缓叶片衰老ZmIPT2基因的玉米遗传转化及功能验证

从玉米自交系郑58中克隆Zm IPT2基因并构建单子叶植物表达载体,通过农杆菌侵染萌动胚方法将其转入玉米自交系K10中,对转基因后代进行分子检测和功能验证。结果表明,Zm IPT2基因c DNA全长969 bp,成功构建其单子叶植物表达载体p CAMBIA5300-ubi-Zm IPT2。农杆菌侵染萌动胚法共转化K10种子5 163粒,获得T0代PCR阳性幼苗48株,其中13株结实收获种子;获得的3个T2代株系PCR阳性率符合3∶1的分离比,且RT-PCR检测呈阳性;2个T2代转基因株系的成熟期叶绿素含量和细胞分裂素含量极显著高于对照,相对绿叶面积和叶面积持绿期极显著或显著高于对照,百粒重和小区产量显著高于对照。结果初步证明,Zm IPT2基因在玉米中的过表达可延缓叶片衰老,提高玉米产量。     

金钗石斛IAA内生细菌筛选及对干旱胁迫下玉米种子萌发的影响

从金钗石斛植株中分离并筛选产吲哚乙酸(IAA)的内生细菌,研究在不同浓度PEG-6000模拟的干旱胁迫条件下,产IAA内生菌发酵上清液浸种处理对玉米种子萌发的影响.从金钗石斛分离出645株内生细菌,通过salkowskis法筛选表明,63.4％的内生菌具有分泌IAA的能力,其中有9株菌分泌量较高,分泌量为12.8～34.5 mg/L.基于16SrRNA基因序列分析,初步鉴定它们为芽孢杆菌属(Bacillus)和类芽孢杆菌属(Paenibacillus)细菌.将内生菌发酵上清液浸种处理玉米种子,在未加PEG以及5％、10％和15％ PEG的干旱胁迫条件下,其种子萌发率与对照组的相当或降低.但部分产IAA内生菌浸种处理可缓解高度干旱胁迫作用:在20％ PEG条件下,有7株内生菌浸种处理后玉米种子萌发率显著提高,较对照组提高了4.7％～13.3％;25％ PEG条件下,内生菌LJYPD 10处理的玉米种子萌发率比对照组显著提高了5.3％.     

“园艺文化”视域下社区居家养老模式探索

当前我国老龄化程度不断加深,而传统养老方式逐渐弱化。建立以园艺文化为载体的社区居家养老模式,可以满足老年人亲近自然的需求;辅助治疗老年人各种身心疾病。现阶段社区园艺文化养老的实现路径包括：政府完善相关法律法规,加大政策扶持和资金支持;社会组织大力发展老年文化产业,提供多样化的养老服务产品;社区通过场地改造、资源整合和文化植入等途径,提供居家养老服务和园艺文化服务。     

不同生长阶段墨瑞鳕脂肪酸组成及主成分分析

为比较不同生长阶段墨瑞鳕肌肉中脂肪酸组成的变化,本研究通过气相色谱技术测定墨瑞鳕幼鱼、成鱼、亲鱼肌肉中脂肪酸含量,并对脂肪酸组成进行主成分分析。结果表明,3个不同生长阶段墨瑞鳕的不饱和脂肪酸(UFA)总量分别为52.2%、58.2%、60.1%;在高度不饱和脂肪酸(HUFA)中DHA含量均最高。随着鱼体生长,墨瑞鳕棕榈油酸、油酸、亚油酸、亚麻酸含量均呈上升趋势,从高到低依次为亲鱼>成鱼>幼鱼;肉豆蔻酸、花生一烯酸、花生四烯酸、EPA、DHA 含量呈下降趋势,从高到低依次为幼鱼>成鱼>亲鱼;UFA总量和单不饱和脂肪酸(MUFA)含量呈上升趋势,从高到低依次为亲鱼>成鱼>幼鱼;多不饱和脂肪酸(PUFA)总量和必需脂肪酸(EFA)总量含量呈先升后降趋势,从高到低依次为成鱼>亲鱼>幼鱼。墨瑞鳕不同生长阶段脂肪酸含量大部分存在显著差异,特别是幼鱼与成鱼的脂肪酸含量(除二十碳三烯酸外)均存在显著差异;肉豆蔻酸、花生一烯酸、花生四烯酸、EPA和DHA等5种脂肪酸是墨瑞鳕的主要特征脂肪酸,这5种主要特征脂肪酸之间均互呈强正相关。随着墨瑞鳕的生长发育应及时提高相应阶段功能性脂肪酸的比例,降低相应阶段呈强负相关的主要特征脂肪酸的比例。本研究结果为墨瑞鳕的开发利用以及饲料营养需求等提供了理论参考。