基于叶绿体DNA accD-psaI序列分析的广西梨地方品种遗传多样性研究

为评价广西梨地方品种的遗传多样性水平,对54份广西梨地方品种的叶绿体DNA高变区域accD-psaI进行测序,并与Genbank中42份梨主栽品种(来自白梨、秋子梨、砂梨、新疆梨、西洋梨和选育品种)的accD-psaI序列做比较。对比发现,广西梨地方品种的accD-psaI序列长度为683～936 bp不等,检测出单倍型(H1～H6)数量6个,简约性信息位点1个,单一突变位点5个,插入/缺失(InDels)片段5个,单倍型多样性(Hd)为0.710,核苷酸多样性(Pi)为0.64×10^-3。单倍型H1、H2和H3为常见单倍型,其中H1在广西各地分布最为广泛。Median-joining Network图显示,单倍型H4和H5为原始单倍型,H2、H3和H8为较进化单倍型。2个原始单倍型只在横县梨地方品种中检测到,同时横县的单倍型类型最多,推测横县为广西梨起源与多样性中心。     

鱼腥草水浸提液对绿豆种子萌发及幼苗生长的化感作用

采用室内培养皿滤纸法,用不同浓度的鲜、干鱼腥草水浸提液对绿豆种子进行处理,分析种子萌发率,萌发指数和幼苗的出苗率、出苗指数,生物量,株高,根长,叶绿素,超氧化物歧化酶(SOD),过氧化物酶(POD)与丙二醛(MDA),探讨鱼腥草对绿豆生长的化感效应。结果表明,鲜鱼腥草水浸提液对在高浓度时的绿豆种子萌发和幼苗出苗,幼苗的SOD、在低浓度时的MDA具有抑制作用,对幼苗株高,根长和生物量和在高浓度时的MDA具有促进作用,对幼苗的POD在小于40%处理浓度时具有促进作用,而随处理浓度增大逐渐转变成抑制作用;干鱼腥草浸提液对绿豆种子萌发,幼苗株高、根长、生物量和SOD具有抑制作用,对幼苗的POD、MDA具有促进作用。暗示了鱼腥草对绿豆生长具有化感效应,这为鱼腥草与绿豆建立合理的种植模式提供理论依据和技术支持。     

Captopril exerts myocardial protective effect in coronary microembolization rats by inhibiting oxidative stress injury and alleviating inflammatory response

AIM: To investigate the effects of captopril (CAP) on oxidative stress injury and inflammatory response induced by coronary microembolization (CME) and its related molecular mechanisms. METHODS: The rat model of CME was established by clamping the rat artery and injecting blood microemboli. The rats were divided into control group, CME group and CME+CAP group, with 6 rats in each group. The myocardial tissues of each group were collected. The changes of myocardial structure and the degree of inflammatory response were analyzed by HE staining. Cardiomyocyte apoptosis was detected by TUNEL staining. The fluorescence intensity of cleaved caspase-3 was detected by immunofluorescence obervation. The protein levels of cleaved caspase-3 and Bax were determined by Western blot. The activity of superoxide dismutase (SOD) and catalase was measured by ELISA. The production of reactive oxygen species (ROS) was detected by DHE fluorescence staining. RESULTS: CAP significantly reduced the myocardial structural changes (P<0.05), inflammatory cell infiltration (P<0.01), number of apoptotic cardiomyocytes (P<0.01), the protein levels of cleaved caspase-3 and Bax (P<0.01), and ROS production levels (P<0.01), but promoted the activity of antioxidant markers SOD and catalase (P<0.01) in the CME rats.CONCLUSION: CAP attenuates CME-induced myocardial injury by resisting oxidative stress and alleviating inflammatory response.     

H_2O_2在外源GA_4解除果梅季节性休眠中的信号作用

以GA_4处理的果梅休眠芽和转PmRGL2基因杨树叶片为材料,通过测定H_2O_2含量、抗氧化酶类活性及其编码基因和信号转导相关基因表达的变化,分析了H_2O_2在外源GA_4解除果梅休眠中的信号作用。结果表明:GA_4处理的果梅花芽的萌芽率显著高于对照,且H_2O_2含量在休眠解除时达到峰值,信号转导相关基因表达发生规律性变化;‘桃形梅’和‘丰后’的需冷量分别为574 CH(低温小时数Chilling hours)和1 108 CH,休眠解除前后,两品种叶芽中的H_2O_2含量没有显著差异,但需冷量低的‘桃形梅’具有更高的抗氧化酶类活性;转Pm RGL2杨树中NADPHoxi下调表达,有利于使H_2O_2含量维持在较低水平,并对赤霉素合成及信号转导相关基因的表达产生影响,而抗氧化酶类活性及其编码基因的表达量上升。推测GA_4通过调控抗氧化酶类活性而影响H_2O_2含量的变化,并引起上下游多种信号相关基因表达水平的变化,最终对休眠解除起作用。     

Identification and establishment of sorting method for isolating CD11b+ myeloid cells in human hepatic metastases from colorectal cancer

AIM: To establish a method for obtaining specific cells in solid tumor tissue by sorting of CD11b⁺ myeloid cells in hepatic metastases from colorectal cancer.METHODS: Tumor tissues were prepared into single cell suspension by mechanical method combined with enzyme digestion, and then the CD11b⁺ myeloid cells were isolated by flow cytometry. The sorted cells were identified by immunocytochemistry. The viability and morphologiy of the sorted cells were evaluated by Giemsa and Typan blue staining. The cell purity was evaluated by flow cytometry.RESULTS: Sufficient numbers of CD11b⁺ cells with high purity were isolated by sorting with flow cytometry from the single cell suspension prepared by mechanical and enzyme digestion. The purity of the cells was confirmed by statistical analysis (P<0.05). The positive rates of the cells before and after sorting were significantly different (P<0.01). The positive cells were verified by immunocytochemical method. Meanwhile, the sorted cells had complete morphology and good activity.CONCLUSION: The CD11b⁺ myeloid cells in solid tumor tissue can be isolated by flow cytometry from the machine-enzyme digestion suspension with high purity, good activity and complete morphology.     

IL-33/ST2 axis in systemic lupus erythematosus in relation to chronic kidney injury and disease activity

AIM: To elucidate the association between chronic kidney injury and interleukin-33 (IL-33; an alarmin)/suppression of tumorigencity 2 (ST2) in patients with systemic lupus erythematosus (SLE).METHODS: Serum levels of IL-33 and soluble ST2 (sST2) were assessed by ELISA in 50 SLE patients and 30 healthy controls (HC).RESULTS: The levels of IL-33 and sST2, and IL-33/sST2 ratio were significantly higher in SLE patients than those in the HC. The IL-33 and sST2 levels were positively associated with SLE disease activity index (SLEDAI), erythrocyte sedimentation rate (ESR), proteinuria and triglyceride, but negatively associated with complement C3. IL-33/sST2 ratio was positively associated with SLEDAI and estimated glomerular filtration rate (eGFR). Independent explanatory variables associated with high IL-33/sST2 included chronic kidney disease (CKD) staging and albumin (R²=0.442), especially CKD staging.CONCLUSION: Elevated serum sST2 and IL-33 levels in SLE patients are correlated with disease activity and risk factors of kidney injury. IL-33/sST2 ratio may serve as a potential biomarker for chronic kidney injury in SLE patients.     

紫花苜蓿耗水规律及灌溉制度优化研究

为研究河套灌区紫花苜蓿的耗水规律,同时对现有灌溉制度进行优化,在田间试验的基础上,设置不同灌水水平对前两茬苜蓿进行了研究。结果表明:现蕾期和开花期是紫花苜蓿耗水的旺盛阶段,该阶段土壤水分亏缺会直接影响苜蓿产量的形成。通过多元线性回归的方法求解得到了两茬紫花苜蓿各生育期的敏感性系数,分别在0.103~0.731和0.041~0.375之间,且以现蕾期和开花期为最大,说明这两个生育阶段为苜蓿生长的关键阶段。以Jensen模型为基础,采用最小二乘法初步优化了两茬紫花苜蓿生育期内的灌溉制度,第1茬灌溉定额以1 400 m3/hm~2为宜,第2茬以2 300 m3/hm~2为宜,两茬灌水次数分别以4次和5次为最优。     

种植方式对关中灌区冬小麦冠层光合及产量性状的影响

为优化配置关中灌区冬小麦种植方式,以小偃22、周麦18和西农805为试验材料,采用二因素随机区组设计,研究宽窄行(B1,30cm+16cm)和等行距(B0,23cm+23cm)种植方式对关中灌区小麦冠层光合及产量性状的影响。结果表明,与B0相比,B1处理对各小麦品种均有增产效果,其中,小偃22和西农805达到显著水平。B1较B0处理,各品种的有效穗数显著提高,小偃22的穗粒数下降不显著,西农805的千粒重显著增加;各品种灌浆期LI显著提高,小偃22和西农805灌浆期的LAI显著提高;小偃22在灌浆前期与灌浆后期的光合指数、周麦18灌浆后期的光合指数显著升高;西农805灌浆前期的光合指数显著降低,而灌浆后期显著升高;小偃22的花前贮藏物质转运量及其对籽粒的贡献率显著提高,西农805花后干物质积累量及其对籽粒的贡献率和西农805的经济系数显著提高,周麦18受种植方式影响较小。综上所述,B1处理能够进一步发挥小偃22和西农805在冠层光截获、同化物质生产、干物质积累与转运、产量构成要素等方面的品种性状优势,从而实现增产。     

淮北地区氮肥群体最高生产力水稻钾素吸收利用特征

以淮北地区有代表性的34个中熟中粳品种为试材,设置7个氮肥水平(0、150.0、187.5、225.0、262.5、300.0、337.5 kg hm~(–2)),得出各品种的最高产量,将该最高产量定义为氮肥群体最高生产力。在此基础上,明确处于顶层水平(≥10.50 t hm~(–2))、高层水平(9.75~10.50 t hm~(–2))、中层水平(9.00~9.75 t hm~(–2))和底层水平(≤9.00 t hm~(–2))水稻品种的钾素积累、分配及转运特征。结果表明,4个生产力等级水稻品种地上部植株、茎鞘和叶片的含钾率在拔节期最高;抽穗期顶层水平品种的这3个参数高于其他3个等级的品种;穗部含钾率差异不显著。随着氮肥群体生产力等级的提高,钾素总积累量增多;拔节前底层水平钾素积累量最多,两年平均为120.56 kg hm~(–2),比例占50.56%,顶层水平为最少,两年平均为108.02 kg hm~(–2),比例占35.99%;拔节至抽穗期和抽穗至成熟期顶层水平钾素阶段积累量及比例显著高于其他3个等级。移栽至拔节期,钾素积累速率为中层底层高层顶层水平,拔节后则为顶层高层中层底层水平。叶片的钾素转运量及转运率明显高于茎鞘;顶层水平叶片的钾素转运量高于其他3个等级,高层水平叶片的转运率最高;穗部增加量随生产力等级的递增而变大;抽穗到成熟期,茎鞘、叶片对穗的钾素转运贡献率表现为底层最高,中层次之,顶层最低。4个等级水稻品种籽粒生产率和百千克籽粒吸钾量差异不显著;钾素偏生产力和钾收获指数均表现为顶层高层中层底层水平。总之,氮肥群体最高生产力越高,水稻中后期植株钾素积累量及器官对钾素的吸收利用效率越显著。抽穗后保持较高的钾素吸收利用及转运效率是高产水稻品种的重要特征。     

稻麦两熟制条件下钵苗机插方式对不同类型水稻品种米质的影响

为探明钵苗机插方式在稻麦两熟地区对水稻米质性状的影响及其品种类型间差异,本文以常规粳稻、杂交籼稻和籼粳交水稻为材料,比较了钵苗机插、毯苗机插和机械直播3种种植方式在稻麦两熟制高产栽培条件下的稻米加工品质、外观品质、营养品质、蒸煮食味品质特性变化及其品种类型间差异。结果表明,钵苗机插的整精米率比毯苗机插和机械直播分别提高1.6%和4.9%(P0.05),整精米产量分别提高7.8%和25.9%(P0.05),改善了稻米加工品质;与毯苗机插和机械直播相比,钵苗机插的稻米垩白米率、垩白面积和垩白度显著增加,对稻米外观品质有不利影响,但钵苗机插精米蛋白质含量较高,有利于稻米营养品质的改良,其精米蛋白质产量分别比毯苗机插和机械直播提高8.7%和28.0%;3种种植方式相比,钵苗机插稻米蒸煮食味品质表现出一定程度的变优趋势,其中,稻米直链淀粉含量、消减值和糊化温度呈钵苗机插毯苗机插机械直播的趋势,胶稠度、峰值黏度、热浆黏度、最终黏度和崩解值呈钵苗机插毯苗机插机械直播的趋势;食味值于种植方式间无显著差异,呈籼粳交水稻和常规粳稻钵苗机插毯苗机插机械直播,杂交籼稻毯苗机插钵苗机插机械直播的趋势。由此得出,钵苗机插不仅能增加稻谷产量,还能改善部分稻米品质特征,是稻麦两熟地区实现高产高效优质协调水稻生产的潜力型机械化种植方式。