肺孢子菌肺炎相关细胞因子的研究进展

肺孢子菌(Pneumocystis carinii/jiroveci,PC为大鼠源,PJ为人源,目前国内外文献通称为PC)是重要的机会性致病菌,其感染可引起卡氏肺孢子菌肺炎(Pneumocystis carinii pneumonia,PCP),常见于免疫缺陷患者。在PCP发病过程中,白介素-10(interleukin-10,IL-10)、干扰素γ(interferonγ,IFNγ)、IL-8、IL-23和IL-33均发挥重要作用,且各细胞因子间可相互作用,协同或拮抗,影响机体炎症的发生及组织损伤。本文对PCP相关细胞因子的研究进展作一综述。     

凤仙花提取物对灰指甲主要致病菌的抑制作用

目的：探讨凤仙花提取物对灰指甲主要致病菌（白色念珠菌、红色毛癣菌）的抑菌作用和机制。方法：试验采用牛津杯法测定凤仙花提取物对主要致病菌的最低抑菌浓度;通过碱性磷酸酶试剂盒测定白色念珠菌、红色毛癣菌内碱性磷酸酶（AKP）的释放量,探究凤仙花提取物对细胞壁的影响。结果：凤仙花提取物对红色毛癣菌的抑制效果更明显,对两种菌的最低抑菌浓度分别为0.125 0 g/mL和0.031 25 g/mL,浓度越大抑菌效果越显著;凤仙花提取物分别处理白色念珠菌、红色毛癣菌2 h、1 d后,两种菌的AKP释放量显著增加。结论：凤仙花提取物能够有效抑制灰指甲主要致病菌（白色念珠菌、红色毛癣菌）的生长,其作用机制可能与破坏细胞壁有关。     

microRNA沉默卡氏肺孢子菌主要表面糖蛋白基因对大鼠卡氏肺孢子菌肺炎的治疗作用

目的探讨靶向卡氏肺孢子菌(Pneumocystis carinii,PC)主要表面糖蛋白基因(Major surface glycoprotein gene,MSG)上游保守序列(Upstream conserved sequence,UCS)的microRNA重组质粒对大鼠卡氏肺孢子菌肺炎(Pneumocystis cariniipneumonia,PCP)的治疗作用。方法将SD大鼠经腹股沟皮下注射地塞米松磷酸钠7周,制备大鼠PCP感染模型。将模型大鼠随机分为5组:microRNA重组质粒治疗组(M组)、磺胺药物治疗组(H组)、生理盐水对照组(C1组)、空载体质粒对照组(C2组)和模型对照组(C3组),其中M组和C1、C2组经尾静脉分别注射含microRNA重组质粒pPC-UCS、生理盐水和空载体,H组用磺胺药物灌胃治疗,C3组不做处理,每日1次,疗程为7 d。1周后吉姆萨染色,油镜下计数大鼠肺组织液印片中PC包囊数;HE染色,光镜观察肺组织病理改变;ELISA法检测大鼠血清中IL-10和IFNγ的表达水平;RT-PCR法检测肺组织中PC MSG-UCSmRNA的表达水平;电镜观察PC的超微结构。结果与C1、C2和C3组相比,M组和H组大鼠肺组织PC包囊数均明显减少(P<0.05),肺组织炎症较轻,大鼠血清IL-10的表达水平均显著降低(P<0.05),而IFNγ的表达水平显著升高(P<0.05),大鼠肺组织PC MSG-UCS mRNA的表达水平均显著降低(P<0.05);电镜观察显示,M组和H组PC包囊表面均出现破损,C1、C2、C3组未发现破损。结论 microRNA重组质粒pPC-UCS对大鼠PCP有明显的治疗作用,为治疗PCP提供了新的思路。     

木质素对硬毛粗毛盖孔菌固态发酵漆酶的影响

解析固态基质木质素与漆酶产量间的关系是促进固态发酵漆酶产业化的基础。考察了木质素含量变化对固态基质可降解性、水分分布特征以及对硬毛粗毛盖孔菌固态发酵漆酶产量的影响。结果表明随着木质素减少,漆酶产量增加,木质素为130 mg/g时,漆酶产量达到161.5 U/g,是对照组的3.42倍,木质素进一步减少漆酶产量未显著增加;木质素减少有利于改善固态基质可降解性,增加微生物可利用水。木质素是影响硬毛粗毛盖孔菌固态发酵产漆酶的重要因素,建立碱预处理工艺改变固态基质木质素含量,是提高固态发酵漆酶产量的重要途径。     

红色诺卡菌细胞壁骨架胶囊的制备及其生物学活性

目的制备红色诺卡菌细胞壁骨架(N-CWS)胶囊,并检测其生物学活性。方法采用超声波法和冷冻干燥法制备N-CWS胶囊,并通过影响因素试验、加速试验及长期试验考察其稳定性,通过小鼠抑瘤试验检测其生物学活性。结果所制备的N-CWS胶囊各项质量指标均符合相关要求,稳定性良好;口服给药对小鼠移植性肿瘤有明显的抑制作用。结论本实验制备的N-CWS胶囊质量稳定,抗肿瘤活性强,适于工业化生产。     

红色诺卡氏菌细胞壁骨架乳液的制备及其安全性研究

以红色诺卡氏菌细胞壁骨架原液以及多种植物提取物为原料制备了一种乳液,并对乳液微生物指标、重金属含量及稳定性以及对KM小鼠破损皮肤修复效果的安全性研究进行评价。结果表明,制备的乳液菌落总数、霉菌和酵母菌数均小于10 CFU/g,耐热大肠菌群、金黄色葡萄球菌、铜绿假单胞菌均未检出;铅、汞、砷、镉重金属含量均未超标;离心试验未发现分层,在耐热、耐寒试验条件下,乳液颜色未发生改变,稳定性良好。小鼠动物实验结果表明,小鼠皮肤破损处涂抹乳液14天愈合率达到了95.80%,比对照组和空白组均提前7 d左右达到90%以上愈合率,无红肿及渗出。表明开发的乳液具有良好的配伍性,性质稳定,无刺激性、过敏性及毒性,可以安全可靠地应用于各行业。     

红色诺卡氏菌高产菌的ARTP诱变选育与发酵条件优化

以红色诺卡氏菌(Nocardia rubra)FIM-PO8为出发菌株,采用常压室温等离子体(ARTP)技术进行诱变,经筛选获得遗传较稳定的Nocardia rubra高产菌株FIM-PO8-16,并通过单因素实验和正交实验优化了菌株FIM-PO8-16的发酵工艺。确定最佳发酵培养基组分为：酵母粉2.5%、葡萄糖2.5%、蛋白胨0.5%、糊精1.0%;最佳发酵条件为：种子液菌龄30 h、初始pH值7.2、接种量2.0%、装料量100 mL/500 mL、转速230 r·min^-1、发酵温度32℃。在此条件下,FIM-PO8-16菌体细胞浓度大幅提高,达到8.31%。     

两株红色糖多孢菌在不同氮源培养条件下的代谢比较

转录组芯片和凝胶阻滞(EMSA)等实验发现,在红霉素高产菌株中,与氮源代谢相关的基因(如glnR、glnB)、铵盐与寡肽转运蛋白基因等在高产菌株中被强烈抑制,可推测在高产菌株和野生菌株中,氮源代谢存在很大差异,并与红霉素合成存在紧密的联系.通过测定4种单一氮源培养条件下的野生模式菌(M菌)和高产菌(A菌)体内的有机酸和氨基酸含量来比较其代谢情况.结果表明,在同一菌株内及不同菌株间,与氮源代谢直接相关的α-酮戊二酸、谷氨酸、谷氨酰胺的含量及与碳源代谢相关的有机酸如苹果酸、柠檬酸的含量在不同的培养基内呈现相反的趋势.     

家用电器的抗菌除菌净化功能标准

<正>我国国家标准GB21551.1-2008《家用和类似用途电器的抗菌、除菌、净化功能通则》已于2008年颁布,2009年3月1日实施。GB21551.1是GB21551标准系列的第一部分,其第二部分是对具体产品规     

焦化废水功能菌的筛选和过程探索

介绍了一种利用Rank氧电极筛选焦化废水功能菌的方法。本实验所用焦化废水中含有结构不明的难降解的成色有机物。从驯化后的活性污泥中分离到一组对该物质有效果的菌株,利用Rank氧电极测定其对该物质的活性大小,筛选出活性较好的菌种用于废水生化处理的进一步研究。对于结构不明的物质降解,这种方法具有快速、简捷、灵敏度高等优点,可广泛应用于功能菌的筛选等方面。     

G-Quadruplex Regulation of VEGFA mRNA Translation by RBM4

In eukaryotes, mRNAs translation is mainly mediated in a cap-dependent or cap-independent manner. The latter is primarily initiated at the internal ribosome entry site (IRES) in the 5′-UTR of mRNAs. It has been reported that the G-quadruplex structure (G4) in the IRES elements could regulate the IRES activity. We previously confirmed RBM4 (also known as LARK) as a G4-binding protein in human. In this study, to investigate whether RBM4 is involved in the regulation of the IRES activity by binding with the G4 structure within the IRES element, the IRES-A element in the 5′-UTR of vascular endothelial growth factor A (VEGFA) was constructed into a dicistronic reporter vector, psiCHECK2, and the effect of RBM4 on the IRES activity was tested in 293T cells. The results showed that the IRES insertion significantly increased the FLuc expression activity, indicating that this G4-containing IRES was active in 293T cells. When the G4 structure in the IRES was disrupted by base mutation, the IRES activity was significantly decreased. The IRES activity was notably increased when the cells were treated with G4 stabilizer PDS. EMSA results showed that RBM4 specifically bound the G4 structure in the IRES element. The knockdown of RBM4 substantially reduced the IRES activity, whereas over-expressing RBM4 increased the IRES activity. Taking all results together, we demonstrated that RBM4 promoted the mRNA translation of VEGFA gene by binding to the G4 structure in the IRES.     

环糊精在聚合反应中的应用研究进展

介绍了环糊精包合作用机理,总结了环糊精对聚合反应机理及聚合反应参数如竞聚率、聚合反应速率、引发活性和链转移常数的影响,为研究聚合物的合成提供理论依据.     

mRNA Localization to the Endoplasmic Reticulum in Plant Endosperm Cells

Subcellular mRNA localization is an evolutionarily conserved mechanism to spatially and temporally drive local translation and, in turn, protein targeting. Hence, this mechanism achieves precise control of gene expression and establishes functional and structural networks during cell growth and development as well as during stimuli response. Since its discovery in ascidian eggs, mRNA localization has been extensively studied in animal and yeast cells. Although our knowledge of subcellular mRNA localization in plant cells lags considerably behind other biological systems, mRNA localization to the endoplasmic reticulum (ER) has also been well established since its discovery in cereal endosperm cells in the early 1990s. Storage protein mRNA targeting to distinct subdomains of the ER determines efficient accumulation of the corresponding proteins in different endosomal storage sites and, in turn, underlies storage organelle biogenesis in cereal grains. The targeting process requires the presence of RNA localization elements, also called zipcodes, and specific RNA-binding proteins that recognize and bind these zipcodes and recruit other factors to mediate active transport. Here, we review the current knowledge of the mechanisms and functions of mRNA localization to the ER in plant cells and address directions for future research.     

Hybridization Networks of mRNA and Branched RNA Hybrids

Messenger RNA (mRNA) is emerging as an attractive biopolymer for therapy and vaccination. To become suitable for vaccination, mRNA is usually converted to a biomaterial, using cationic peptides, polymers or lipids. An alternative form of converting mRNA into a material is demonstrated that uses branched oligoribonucleotide hybrids with the ability to hybridize with one or more regions of the mRNA sequence. Two such hybrids with hexamer arms and adamantane tetraol as branching element were prepared by solution-phase synthesis. When a rabies mRNA was treated with the branched hybrids at 1 M NaCl concentration, biomaterials formed that contained both of the nucleic acids. These results show that branched oligoribonucleotides are an alternative to the often toxic reagents commonly used to formulate mRNA for medical applications.     

Dwell-Time Distribution,Long Pausing and Arrest of Single-Ribosome Translation through the mRNA Duplex

Proteins in the cell are synthesized by a ribosome translating the genetic information encoded on the single-stranded messenger RNA (mRNA). It has been shown that the ribosome can also translate through the duplex region of the mRNA by unwinding the duplex. Here, based on our proposed model of the ribosome translation through the mRNA duplex we study theoretically the distribution of dwell times of the ribosome translation through the mRNA duplex under the effect of a pulling force externally applied to the ends of the mRNA to unzip the duplex. We provide quantitative explanations of the available single molecule experimental data on the distribution of dwell times with both short and long durations, on rescuing of the long paused ribosomes by raising the pulling force to unzip the duplex, on translational arrests induced by the mRNA duplex and Shine-Dalgarno(SD)-like sequence in the mRNA. The functional consequences of the pauses or arrests caused by the mRNA duplex and the SD sequence are discussed and compared with those obtained from other types of pausing, such as those induced by “hungry” codons or interactions of specific sequences in the nascent chain with the ribosomal exit tunnel.     

冰冻血小板的功能及其临床疗效

目的观察冰冻血小板的功能及其临床疗效。方法对血小板冰冻前后的回收率、黏附率、聚集率和血小板第3因子(PF3)活性进行检测,并比较新鲜机采血小板与冰冻机采血小板临床应用的疗效。结果冰冻血小板的回收率为70.93%±15.23%,黏附率、聚集率和PF3活性与新鲜机采血小板差异无统计学意义,且临床疗效良好。结论冰冻血小板的功能没有变化,对因血小板减少所致的出血具有良好的止血作用。