Molecular characterization of a novel pattern recognition protein from nonspecific cytotoxic cells: sequence analysis, phylogenetic comparisons and anti-microbial activity of a recombinant homologue

Nonspecific cytotoxic cells (NCC) are the first identified and most extensively studied killer cell population in teleosts. NCC kill a wide variety of target cells including tumor cells, virally transformed cells and protozoan parasites. The present study identified a novel evolutionarily conserved oligodeoxynucleotide (ODN) binding membrane protein expressed by channel catfish (Ictalurus punctatus) NCC. Peptide fingerprinting analysis of the ODN binding protein (referred to as NCC cationic anti-microbial protein-1/ncamp-1) identified a peptide that was used to design degenerate primers. A catfish NCC cDNA library was used as template with these primers and the PCR-amplified product was sequenced. The translated sequence contained 203 amino acids (molecular mass of 22,064.63 Da) with characteristic lysine rich regions and a pI=pH 10.75. Sequence comparisons of this protein indicated similarity to zebrafish (51.2%) histone family member 1-X and (to a lesser extent) to trout H1. A search of EST databases confirmed that ncamp-1 is also expressed in various tissues of channel catfish as well as zebrafish. Inspection for signature repeats in ncamp-1 and comparisons with histone-like peptides from different species indicated the presence of multiple lysine based motifs composed of AKKA or PKK repeats. The novel protein was cloned, expressed in E. coli and the recombinant was used to generate rabbit anti-serum. The recombinant ncamp-1 bound GpC and CpG ODNs and was detected with homologous anti-ncamp-1 polyclonal antibodies. Western blots of NCC membranes using anti-ncamp-1 serum detected a 29 kDa protein. Binding competition experiments demonstrated that anti-ncamp-1 antibodies and GpC bound to the same protein on NCC. Two different truncated forms of ncamp-1 as well as the full-length recombinant protein exhibited anti-microbial activity. The present study demonstrated the expression by NCC of a new membrane protein that may participate in the recognition of bacterial DNA and as such participate in innate anti-microbial immune responses in teleosts.     

长期喂饮钇对子代大鼠免疫功能的影响

目的探讨长期摄入稀土Y3+对子代大鼠免疫功能的影响。方法40只Wistar大鼠,随机分为4组,分别喂饮钇浓度为0、0·534、53·4和5340mg/L的饮用水。6个月后,处死F1代大鼠,心脏取血,摘取胸腺、睥,称重;流式细胞仪测定T细胞亚群CD3、CD4、CD8百分率,计算CD4/CD8比值;ELISA试剂盒测定血清中IgG、IgM含量。结果饮水中稀土浓度为0·534mg/L时,IgM、IgG含量明显升高(P<0·05),其他指标无明显变化;浓度为53·4mg/L时,各指标无明显变化;浓度为5340mg/L时,大鼠的CD3、CD8、IgM、IgG含量显著降低(P<0·05),CD4/CD8比值显著提高(P<0·05),CD4无明显变化;各剂量组大鼠脏器指数亦无明显变化。结论长期喂饮钇对子代大鼠的细胞免疫和体液免疫均有一定的影响。     

PRRSV Induces HMGB1 Phosphorylation at Threonine-51 Residue to Enhance Its Secretion

Porcine reproductive and respiratory syndrome virus (PRRSV) induces secretion of high mobility group box 1 (HMGB1) to mediate inflammatory response that is involved in the pulmonary injury of infected pigs. Our previous study indicates that protein kinase C-delta (PKC-delta) is essential for HMGB1 secretion in PRRSV-infected cells. However, the underlying mechanism in HMGB1 secretion induced by PRRSV infection is still unclear. Here, we discovered that the phosphorylation level of HMGB1 in threonine residues increased in PRRSV-infected cells. A site-directed mutagenesis study showed that HMGB1 phosphorylation at threonine-51 was associated with HMGB1 secretion induced by PRRSV infection. Co-immunoprecipitation (co-IP) of HMGB1 failed to precipitate PKC-delta, but interestingly, mass spectrometry analysis of the HMGB1 co-IP product showed that PRRSV infection enhanced HMGB1 binding to ribosomal protein S3 (RPS3), which has various extra-ribosomal functions. The silencing of RPS3 by siRNA blocked HMGB1 secretion induced by PRRSV infection. Moreover, the phosphorylation of HMGB1 at threonine-51 was correlated with the interaction between HMGB1 and RPS3. In vivo, PRRSV infection also increased RPS3 levels and nuclear accumulation in pulmonary alveolar macrophages. These results demonstrate that PRRSV may induce HMGB1 phosphorylation at threonine-51 and increase its interaction with RPS3 to enhance HMGB1 secretion. This finding provides insights into the pathogenesis of PRRSV infection.     

稀土对甘蔗增产增糖机理的探讨

以盆栽试验为主,结合大田生产试验来研究稀土微肥对甘蔗增产增糖的机理。研究结果表明,稀土能提高甘蔗叶片叶绿素含量,改善叶片的超微结构,增加叶肉细胞和维管束鞘细胞的叶绿体数,增加叶肉细胞叶绿体中的基粒数和基粒片层数,增大叶片光合膜面积,能促进根系生长,提高根系活力,促进根系对N、P、K等营养元素的吸收;能提高甘蔗体内K、Ca、Zn、Cu等元素的水平,而相对降低Mn、Na等元素的水平;能提高甘蔗伸长期叶片酸性转化酶活性,降低成熟期叶片酸性转化酶活性,提高伸长期及成熟期叶片中性转化酶活性,协调甘蔗的生长和蔗糖分的积累,能调节细胞的渗透压,维持细胞膜结构和功能的稳定性和完整性,增强细胞壁的伸缩性,提高甘蔗的抗旱性;能改善质膜的透性,提高其选择吸收能力,减轻高浓度Na~+的毒害,提高甘蔗的耐盐能力。     

芦丁稀土配合物的合成及药效学初步研究

目的　探索芦丁与稀土元素配位前后药效学的变化。方法　采用小鼠扭体法和耳壳肿胀法对芦丁与稀土元素配位前后镇痛与抗炎作用进行比较。结果　与NS组比较,芦丁及其配合物可明显减少醋酸所致小鼠扭体次数( P <0 0 5或P <0 0 1);与芦丁组比较,其各配合物组的镇痛作用更强(P <0 0 1)。同样,与NS组比较,芦丁及其配合物对二甲苯引起的小鼠耳壳肿胀有明显的抗炎作用(P <0 0 5或P <0 0 1);而各配合物的抗炎作用又强于芦丁组(P <0 0 5或P <0 0 1)。结论　芦丁稀土配合物较芦丁的镇痛、抗炎作用明显增强。     

“培土生金”法在新型冠状病毒肺炎疫情中对慢性阻塞性肺疾病的作用

目前,新型冠状病毒肺炎(简称"新冠肺炎")在我国已经得到阶段性地控制,但在世界范围,患者仍不断增加,且仍有不少境外输入病例不断进入国内。因此,现阶段对新冠肺炎疫情防控仍处于关键时期。慢性阻塞性肺疾病(COPD)是我国中老年人常见的呼吸系统疾病,患者常存在肺脾气虚的证候表现,加之免疫力、抵抗力较低,是新冠肺炎的易感人群。COPD与新冠肺炎同属呼吸系统疾病,二者在病因上具有一定的相似性,且具有相同的病变脏腑。二者在发病过程中,都会产生"湿、毒、热"的病理因素,影响肺、脾与大肠等脏腑的生理功能,致使其在病机上具有相关性,且贯穿疾病的始终。脾胃的盛衰是治疗新冠肺炎进退的关键。培土生金法有健脾益肺,化湿祛毒的含义,可以同时调节肺、脾、大肠三个脏腑,改善相关脏腑的功能,达到肺肠同治、肺脾同调的作用。因此培土生金法不仅是治疗COPD的常用方法,也可以作为本次新冠肺炎"湿、毒、热"病理因素的治疗方法。参苓白术散是培土生金法的代表方剂,有益气健脾化湿的功效,契合本次新冠肺炎"湿毒疫邪"的主要病机,对COPD患者具有扶正祛邪,增加免疫力的作用。同时也可以采用培土生金法选取相应穴位艾灸,加强对新冠肺炎的预防。因此,培土生金法可作为疫情期间COPD患者预防新冠肺炎的治疗方法。     

大鼠心肌梗死后心肌高迁移率族蛋白HMGB1的时程变化

目的 探讨大鼠心肌梗死模型后不同时间高迁移率族蛋白(HMGB1)的时程变化.方法 结扎SD大鼠左冠状动脉前降支造成左室大面积心梗,分别于术后1、2、4、8周测心功能判断造模是否成功后开胸取心脏.分别运用实时荧光定量PCR和Western蛋白印迹技术观察心肌梗死后不同时间点HMGB1在mRNA和蛋白水平的表达变化.结果 心功能检测提示造模成功,心梗大鼠术后早期(1 w)HMGB1 mRNA表达上调(P＜0.01),而心梗后期(8周)则表达显著减少(P＜0.01).与mRNA水平变化类似,HMGB1蛋白水平在心肌梗死组大鼠术后早期(1～2周)表达水平增加(P＜0.01),而心梗后期(8周)则显著下调(P＜0.05).结论 HMGB1作为炎症调节因子,在心梗早期对心肌的炎性反应进行调控;并在心梗后期参与调节基因转录,进行心肌修复.在心梗的不同阶段对HMGB1的表达进行干预有望减少心梗并发症,改善预后.提高患者长期存活率.     

稀土元素在光催化降解抗生素中的应用研究进展

摘要：抗生素广泛应用于医疗和农业生产之中,由于传统的废水处理工艺不能够有效地去除废水中的抗生素,导致目前环 境中已经广泛检测到抗生素的存在。为了预防抗生素污染扩散带来的危害,人们投入了大量的资源研究抗生素的去除方法。本 文参考国内外文献总结了近几年稀土元素在光催化降解抗生素中的应用研究情况,深入揭示了稀土元素在光催化降解抗生素应 用中发挥的作用。主要内容包括：稀土元素掺杂、稀土元素参与构建异质结和稀土元素掺杂与异质结共用的光催化降解;稀土 元素应用在光催化降解抗生素中的3种方法的分析对比;对稀土元素应用于光催化降解抗生素的未来展望。     

miR-31调控PAX9对肺癌细胞增殖和侵袭能力的影响

目的 研究miR-31调控配对盒基因9(PAX9)对肺癌细胞侵袭和增殖能力的影响.方法 运用免疫组织化学检测肺癌组织和癌旁正常组织PAX9蛋白的表达;运用荧光定量PCR检测肺癌组织、癌旁正常组织和肺癌细胞株M14中miR-31的表达.通过转染miR-31-inhibitor下调M14细胞中miR-31的表达,双荧光素酶活性检测miR-31对PAX9转录活性的影响;Transwell侵袭实验检测miR-31对M14细胞的侵袭能力的影响;平板克隆实验检测miR-31对M14细胞的增殖能力的影响.结果 与癌旁正常组织比较,PAX9蛋白在肺癌组织中表达降低,miR-31在肺癌组织中表达明显升高(P<0.05);双荧光素酶活性检测结果显示,miR-31可以直接调控PAX9的转录活性;抑制miR-31的表达后,肺癌细胞株M14的PAX9蛋白表达水平上调,侵袭和转移能力明显降低(P<0.05).结论 miR-31靶向PAX9的表达,从而调控肺癌细胞的侵袭和增殖能力.