Identification and functional analysis of arabinogalactan protein expressed in pear pollen tubes

Arabinogalactan proteins (AGPs) are widely distributed in the plant kingdom and play a vital role during the process of plant sexual reproduction.  In this study, we performed a comprehensive identification of the PbrAGPs expressed in pear pollen and further explored their influences on pollen tube growth.  Among the 187 PbrAGPs that were found to be expressed in pear pollen tubes, 38 PbrAGPs were specifically expressed in pollen according to the RNA-seq data.  The PbrAGPs were divided into two groups of highly expressed and specifically expressed in pear pollen.  We further tested their expression patterns using RT-PCR and RT-qPCR.  Most of the PbrAGPs were expressed in multiple tissues and their expression levels were consistent with reads per kilobase per million map reads (RPKM) values during pollen tube growth, implying that PbrAGPs might be involved in the regulation of pear pollen tube growth.  We also constructed phylogenetic trees to identify the functional genes in pear pollen tube growth.  Therefore, 19 PbrAGPs (PbrAGP1 to PbrAGP19) were selected to test their influences on pollen tube growth.  Recombinant proteins of the 19 PbrAGP-His were purified and used to treat pear pollen, and 11 of the PbrAGP-His recombinant proteins could promote pear pollen tube growth.  Additionally, pollen tube growth was inhibited when the expression levels of PbrAGP1 and PbrAGP5 were knocked down using an antisense oligonucleotide assay.  PbrAGP1 and PbrAGP5 were localized in the plasma membrane and might not alter the distribution of pectin in the pollen tube.  In summary, this study identified the PbrAGPs expressed in pear pollen and lays the foundation for further exploring their functions in pollen tube growth.     

稻蟹共作与常规稻田蜘蛛群落组成及多样性分析

稻蟹共作是一种新型的稻田生态种养殖技术,对推动生态农业发展具有重要意义。目前对稻田蜘蛛的研究仅限于常规稻田,而关于稻蟹共作系统蜘蛛方面的研究尚少见报道。本试验旨在研究稻蟹共作田与常规稻田中蜘蛛群落的组成及多样性特点,探索稻蟹共作田蜘蛛的发生特点,为进一步研究稻蟹共作系统生物多样性特征奠定基础。试验采用吸虫器抽吸法,系统调查了盘锦稻蟹共作田和常规稻田蜘蛛物种组成,并分析了蜘蛛群落多样性特点。结果表明：这两类稻田共调查11科31种蜘蛛,狼蛛科（Lycosidae）、皿蛛科（Linyphiidae）和园蛛科（Araneidae）数量最多,占总蛛数70%;稻蟹共作田蜘蛛个体数量显著高于常规稻田。2类稻田蜘蛛优势种均为草间钻头蛛（Hylyphantes graminicola）和拟水狼蛛（Pirata subpiraticus）。多样性指数表明,6月初蜘蛛Shannon-Wiener多样性指数最低,8-9月蜘蛛群落最高;而均匀度指数、丰富度指数总体与其呈正相关,优势度指数与其呈负相关;2类稻田蜘蛛群落多样性特点基本一致。研究结果表明稻蟹共作田和常规稻田蜘蛛种类和多样性特点没有显著差异,但蜘蛛个体数量有显著差异,即稻蟹共作田蜘蛛个体数量显著高于常规稻田。     

耕播方式及秸秆还田对皖北小麦产量和品质的影响

为在皖北地区确定一种比较适宜的耕播方式和秸秆还田组合技术,以"皖麦68"为试验材料,研究了不同耕播方式和秸秆还田对皖北小麦产量和品质的影响。结果表明,不同秸秆还田和耕播方式对小麦开花期旗叶光合参数以及叶绿素含量有显著影响,秸秆还田大体上提高了小麦净光合速率和叶绿素含量并且降低了胞间CO2浓度和旗叶MDA积累,在秸秆还田下,耕翻镇压(PCL)较旋耕(RL)显著提高了小麦光合性能,同时降低了MDA积累量;在小麦产量上,PCL(耕翻+镇压)和SPCL(秸秆+耕翻+镇压)产量最高,分别为9 048和8 889 kg·hm-2,且两者无显著差异;此外,秸秆还田显著提高小麦的籽粒品质性状,其中SPCL小麦籽粒品质相对较好。综合以上,秸秆还田配合耕翻镇压的耕作方式进行机械条播更适合皖北地区的小麦种植。     

套袋红富士苹果贮藏过程中硬度及相关酶的变化

以套袋红富士苹果为试材,部分样品贮藏前用保鲜剂1-MCP进行了处理,以不套袋红富士果实为对照,测定了果实在冷藏条件下的硬度及相关酶的变化,目的在于探讨套袋红富士苹果贮藏过程中硬度与相关酶的变化,为套袋红富士苹果的贮藏提供依据。结果表明：随着贮藏时间的延长,红富士硬度均呈降低趋势,套袋果实降幅小于对照。在0℃贮藏条件下,套袋红富士苹果的硬度及相关酶与对照果实变化趋势无明显差异,但套袋果实抗氧化酶活性、MDA含量与对照有差异。贮藏结束时,红富士套双层内红袋、双层内黑袋果实MDA含量分别为对照果实的79.3%、84.5%,SOD活性分别是对照的1.28倍、1.24倍,CAT活性分别是对照的1.26倍、1.28倍,而其POD、ACS、ACO活性均低于对照。1-MCP显著抑制了红富士果实贮藏期间果实硬度的降低、MDA含量的升高和抗氧化酶活性的变化。     

Effect of p19ARF on growth and apoptosis of leukemia cells

AIM:To study the effect of p19ARF on the biological behavior of human leukemia cells. METHODS:p19ARF was cloned in eukaryotic expression vector pcDNA3.1 and transferred into INK4a/ARF locus-deficient leukemia cells HEL and K562. The changes in biological characteristics of the two p19ARF-transfected cells were observed.RESULTS:The growth of the p19ARF-transfected HEL cells was significantly inhibited compared with the vector-transfected cells; Cell cycle analysis showed that the expression of foreign p19ARF gene resulted in G1 phase cell cycle arrest and apoptosis cell death in some of HEL cells. However, p19ARF had no marked effects on the growth of K562 cells with p53 gene mutation and did not induce apoptosis in K562 cells.CONCLUSION:p19ARF suppressed the growth of leukemia cells by p53-dependent pathway.     

Expression of Survivin and its relationship to prognosis in human hepatocellular carcinoma

AIM: To study the expression of Survivin and its relationship to prognosis in human hepatocellular carcinoma(HCC).METHODS: The expression of Survivin protein in 83 cases of HCC and their neighboring noncancerous tissues was detected by immunohistochemistry.The expression of Survivin mRNA in 11 cases of HCC and their neighboring noncancerous tissues was detected by semi-quantitative RT-PCR.RESULTS: Survivin protein expression was detected in 53 of 83 (63.9%) HCC tissues and 21 of 53 (39.6%) corresponding noncancerous tissues.22 of 53 Survivin-positive HCCs (41.5%) showed punctate nuclear staining in HCC cells,24 of 53 Survivin-positive HCCs (45.3%) showed cytoplasmic staining in HCC cells and the remaining 7 showed both nuclear and cytoplasmic staining.The positive rates of nuclear Survivin expression in cases of envelope invasion or tumor metastasis were significantly higher than those in cases without envelope invasion or tumor metastasis (P<0.05).The patients with positive nuclear Survivin expression had the higher chance of poor prognosis than those with negative nuclear Survivin expression (P<0.01).Survivin mRNA was detected in all the 11 HCC and 5 of 11 (45.5%) neighboring noncancerous tissues.CONCLUSION: There is a high expression of Survivin in HCC and positive nuclear Survivin may play an important role in malignant biological behavior and prognosis of HCC.     

Research on Antimicrobial Resistance Characteristics of Enterococcus spp. from Companion Animals in Beijing

In order to study the tolerance of Enterococcus spp.from companion animals to common antibiotics in Beijing,320 samples were collected from dogs and cats in a pet hospital in Beijing from May 2015 to January 2016.The strains were isolated by selective culture medium and identified by VITEK-2 Compact 60.The sensitivity test of 11 kinds of common antibiotics in 8 categories was carried out for the isolated and identified strains.At the same time,the high-level gentamicin and high-level streptomycin resistance test were carried out to analyze the drug resistance and multiple drug resistance of Enterococcus.A total of 318 strains of non repetitive enterococci with different colony morphology and biochemical characteristics were obtained.The isolation rates of Enterococcus faecalis (49.06%) and Enterococcus faecium (29.87%) were higher.The resistance rates of Enterococcus to high-level gentamicin and high-level streptomycin were 39.94% and 43.40%,respectively.The resistance rates to tetracycline (78.62%),erythromycin (67.30%) and quinoproptin dapfoptin (43.71%) were very high.All of them were sensitive to tigecycline,and the non-resistant rate to vancomycin and nitrofurantoin was also high (98.74%).Enterococcus tested showed different degrees of resistance to class 1 to class 7 antibiotics,and the multidrug resistance was common,and the multidrug resistance rate was as high as 57.23%.The number of resistant antibiotics was the highest (n=65).A total of 44 different drug resistance profiles were obtained.Among them,erythromycin-quinoptin-daptoptin-tetracycline-high level aminoglycoside resistant spectrum accounted for the highest proportion (45/318,14.15%).This study confirmed that Enterococcus spp.isolated from companion animals in Beijing was highly resistant to common antibiotics,and multidrug resistance was prevalent.Therefore,it was necessary to strengthen the monitoring of drug resistance.     

伪狂犬病病毒变异株gC抗体间接ELISA检测方法的建立及初步应用

本研究旨在建立变异伪狂犬病病毒FJ-2012株gC蛋白抗体间接ELISA检测方法,掌握不同猪场猪群的gC抗体水平情况。将FJ-2012株gC基因连接至pCzn1载体,转染至Arctic express(DE3)感受态细胞,IPTG诱导表达产物经SDS-PAGE和Western blot验证,通过矩阵法试验、临界值的确定、特异性试验、重复性和敏感性试验,建立PRV-gC抗体间接ELISA检测方法,并对源于不同猪场的280份血清进行PRV-gC抗体检测。结果表明,成功表达获得FJ-2012株pCzn1-gC重组蛋白;建立的间接ELISA方法的最佳抗原包被浓度为10 μg·mL^-1和最佳样品血清稀释比例为1∶50,阴性和阳性判定的OD_{650 nm}临界值为0.406~0.438,介于之间的判定为可疑;临床检测结果显示,120份盲样猪血清PRV-gC抗体阳性率为91.67%、PRV-gB抗体阳性率为95.00%,两种抗体检测结果的整体符合率为95.83%;PR不稳定的猪场血样PRV-gC抗体阳性率为96.25%(77/80),而PRV已净化的种猪场血样PRV-gC抗体阳性率为78.75%(63/80)。因此,建立的PRV变异株gC抗体间接ELISA检测方法为临床猪血清抗体检测提供了特异、灵敏和稳定的技术,也为开展变异PRV血清学调查奠定基础。     

高职“五年一贯制”学生逆反心理的探析

"五年一贯制"的学生的逆反心理的产生的原因很多,其校正过程与其班主任的教育引导有很大的关系,所以班主任应因势利导,作好学生逆反心理的转化工作。     

沙棘果油的毒性实验研究

沙棘果油以15ml/kg,30ml/kg及60ml/kg分组给小白鼠ig;10ml/kg,20ml/kg及40 ml/kg分组给大白鼠ig.观察7 d,皆未测出LD50.给小白鼠SC10ml/kg,20 ml/kg;给兔背部完整或破损皮肤涂2.5 ml/kg及10ml/kg,观察7 d,未见明显中毒症状.按2ml/kg,5 ml/kgg及10ml/kg每天分组给大白鼠ig,连续90 d.给油组鼠的体重,血液学检查,血液生化学检查等,与对照组比较皆无显著性差异(P＞0.05).给油组鼠的心、肝、脾、肺、肾、肾上腺、胸腺、睾丸、子宫卵巢等器官肉眼观察、及病理切片组织形态光镜检查,均未发现明显损害性病理改变,与对照组比较,未发现明显差异.对豚鼠皮肤,兔眼睛及阴道局部应用,未见明显刺激反应.豚鼠皮肤过敏试验,未见过敏反应.