jn219的分离纯化及其抗人巨细胞病毒活性的初步研究

目的:从真菌中分离纯化单峰物质,并对其抗人巨细胞病毒活性进行初步研究。方法:发酵获得菌丝体,通过丙酮/乙酸乙酯提取、硅胶柱层析、高效液相色谱制备,从菌丝体中获得单峰物质,经紫外光谱、质谱分析,采用细胞病变效应(CPE)抑制法,通过中性红染色计算病毒滴度,跟踪其抗病毒活性。结果:分离到的单峰物质(命名为jn219)紫外吸收峰为220nm,相对分子质量为519,半数中毒浓度(TD50)为50μg/mL,半数抑毒浓度(IC50)为1μg/mL,抑毒指数(TI)为50。结论:初步证实单峰物质jn219在体外具有抗人巨细胞病毒的活性。     

绞股蓝内生真菌抗大肠杆菌抗菌机制的研究

【目的】药用植物内生真菌是一种新型抗生素的微生物资源,研究绞股蓝内生真菌JY25的抗菌机制对内生真菌的研发具有重要意义。【方法】以二倍稀释法测定发酵液的最小抑菌浓度(MIC)和最小杀菌浓度(MBC);以MIC测定发酵液对大肠杆菌生长的抑制作用;扫描电镜观察发酵液作用下的大肠杆菌形态变化;同时,以β-半乳糖酶、碱性磷酸酶和电导率测定发酵液对细胞膜和细胞壁的损伤效果;采用考马斯亮蓝法检测发酵液对蛋白质合成的影响。【结果】JY25发酵液对大肠杆菌MIC为7 g/L、MBC为14 g/L;MIC浓度的发酵液使细菌对数生长期延迟12 h,菌体形态发生严重的畸形和破损;随着抑菌作用时间的延长,β-半乳糖酶含量增加、电导率增加,同时,实验发现大肠杆菌蛋白质合成异常,未检测到碱性磷酸酶。【结论】绞股蓝内生真菌JY25主要以破坏细菌的细胞膜及影响细菌蛋白质合成而抑制细菌生长。     

人巨细胞病毒潜伏感染机制研究新进展

人巨细胞病毒(HCMV)是疱疹病毒科β亚科中基因组最大的DNA病毒,所编码的蛋白质超过227种,具有种属特异性[1].     

烟草内生真菌及其提取物的抗细菌活性(英文)北大核心CSCD

从健康烟草的根和茎中分离到38株内生真菌,对23株代表性内生真菌菌株进行了形态观察和ITS-r DNA分析,共鉴定出18个属,其中Acremonium(菌株Nitaf01和Nitaf02)、Fusarium(菌株Nitaf07、Nitaf08和Nitaf09)、Penicillium(菌株Nitaf18和Nitaf20)和Plectosphaerella(菌株Nitaf11和Nitaf12)为主要属,有13个属(Acremonium、Cladosporium、Clonostachys、Ilyonectria、Mortierella、Myriodontium、Petriella、Plectosphaerella、Podospora、Purpureocillium、Rhizopycnis、Stephanonectria和Thielavia)的真菌为首次从烟草中分离得到。5株内生真菌(Colletotrichum sp.Nitaf05、Fusarium sp.Nitaf07、Purpureocillium sp.Nitaf13、Penicillium sp.Nitaf20和Rhizopycnis sp.Nitaf22)的菌丝和发酵液提取物均表现出较强的抗细菌活性。结果表明烟草存在丰富的内生真菌,这些内生真菌具有生产抗菌活性成分和作为生防菌剂应用的潜力。     

青蒿提取物抗单纯疱疹病毒活性研究

用细胞病变效应(CPE)法证明了青蒿水提物具有抗单纯疱疹病毒Ⅱ型(HSV—2)活性,通过初步分离纯化得到抗HSV—2活性的有效成分。用MTT法研究了青蒿水提物和有效成分的细胞毒性和抗HSV—2活性,CC50分别为5．29mg／ml和4,94mg／ml,IC50分别为1．45mg／ml和0．128mg／ml,TI分别为3．65和38．6。以0．5mg／ml的无环鸟苷(ACV)作为阳性对照,结果显示有效成分在体外可以明显抑制HSV—2的致细胞病变作用,效果与ACV相当。     

1株Alternaria sp.真菌菌丝提取物对玉米种子发芽促进作用的研究

从健康的野生山枣根部分离得到1株真菌,经分子鉴定其为支链孢属Alternaria sp.并且对其进行液体培养到生长期后,菌丝体用4层纱布滤出,40℃烘干,研磨后用乙醇浸提3次,合并滤液,并测定其菌丝醇提取物的浓度,配成1、10、100μg/mL的浓度,进行玉米种子催芽试验。结果表明,浓度为1、10μg/mL的醇提取物,均可提高玉米种子的发芽指数,而浓度为100μg/mL的醇提取物则会降低玉米种子发芽指数。     

人巨细胞病毒潜伏感染机制的研究进展

人巨细胞病毒可通过原发感染或者潜伏感染再激活而广泛传播.基于对人巨细胞病毒AD169株和Towne株基因测序的完成,以及人巨细胞病毒的基因功能研究及其相关动物模型如小鼠模型、猪模型、恒河猴模型等的研究,人巨细胞病毒感染的潜伏机制研究取得了一定进展.本文从人巨细胞病毒的感染机制、免疫应答和免疫逃避三方面对人巨细胞病毒潜伏感染机制的研究现状进行简要综述.     

西洋参内生真菌抑菌活性的初步研究

以金黄色葡萄球菌、蜡状芽胞杆菌、枯草芽胞杆菌、大肠杆菌、鼠伤沙门氏菌及肠炎沙门氏菌为测试菌种,对从西洋参(Panax quinquefolium L.)的茎和叶中分离得到的36株内生真菌进行抑菌活性试验,并测定活性菌株的代谢产物和不同极性物质对测试病菌的抑菌活性。试验筛选出2株具有明显抑菌活性的内生真菌,它们的代谢产物和不同极性物质对金黄色葡萄球菌和蜡状芽胞杆菌的抑菌效果最佳,其中胞外多糖和正丁醇提取物的抑菌效果较好。     

23株海洋真菌的分子鉴定及其抗植物病原真菌和细胞毒活性研究

从南海沉积物中分离得到23株海洋真菌,通过ITS测序进行鉴定。以新月弯孢霉(Curvularia lunata)、柱枝双胞霉(Cylindrocladium scoparium)、链格孢(Alternaria alternata)、胶孢炭疽菌(Colletotrichum gloeosporioides)为受试植物病原真菌,以神经胶质瘤细胞(SF-268)、乳腺癌细胞(MCF-7)、大细胞肺癌细胞(NCI-H460)和肝癌细胞(HepG-2)为受试肿瘤细胞,分别采用生长速率法和SRB法对这些菌株的发酵液粗提物进行抗植物病原真菌和细胞毒活性测试,发现11个菌株的粗提物在浓度为50 mg/mL时,对至少1种受试植物病原真菌的抑制率在50%以上,有9个菌株的粗提物在浓度为100μg/mL时,对至少1种肿瘤细胞株的抑制率在80%以上,其中菌株Eupenicillium sp.FS100、Penicillium sp.FS105、Dichotomomyces cejpii FS110、Acaromyces ingoldii FS121对植物病原真菌和(或)肿瘤细胞具有明显的抑制活性。     

研究miR-219下调TGFBR2影响ENDMT途径抑制急性心肌梗死

目的: 主要是miR-219通过对TGFBR2调控机制,介导ENDMT途径缓解急性心肌梗死的发展。方法: qRT-PCR检测AMI患者及AMI小鼠血清中miR-219的表达量;过microRNA靶基因数据库TargetScan进行筛选预测;萤光素酶报告基因法及qRT-PCR分析TGFBR2与miR-219的调控机制;通过心脏超声心动图检测AMI小鼠心肌注射miR-219慢病毒4周后的血分数(LVEF);采用qRT-PCR检测心肌注射miR-219慢病毒的AMI小鼠中Nppa 的mRNA的表达量;通过Masson’s trichrome染色法检测小鼠4周后左心室纤维化变化;使用α平滑肌肌动蛋白(α-SMA)对小鼠左室切片进行免疫组化分析;通过Western blot检测P-smad2、P-smad3及TGFBR2缺氧诱导蛋白磷酸化的表达水平。结果: miR-219对AMI有调控作用;miR-219可抑制TGFBR2的mRNA表达,而miR-219 inhibitor可以抑制这种下调效果,miR-219对TGFBR2具有抑制调控性;miR-219可抑制急性心肌梗死的进程,促进梗死心肌功能的恢复;miR-219能促进AMI小鼠心肌组织血管的新生和成熟,最终心脏收缩能力上升,心功能恢复;miR-219能抑制TGFBR2抑制EndMT途径,导致缓解AMI的病理进程。结论: miR-219能通过抑制TGFBR2影响EndMT途径,心肌纤维化减少,促进血管的新生和成熟,心功能恢复,抑制AMI的病理发展。     

A Novel Zinc Finger Protein 219-like (ZNF219L) is Involved in the Regulation of Collagen Type 2 Alpha 1a (col2a1a) Gene Expression in Zebrafish Notochord

The notochord is required for body plan patterning in vertebrates, and defects in notochord development during embryogenesis can lead to diseases affecting the adult. It is therefore important to elucidate the gene regulatory mechanism underlying notochord formation. In this study, we cloned the zebrafish zinc finger 219-like (ZNF219L) based on mammalian ZNF219, which contains nine C2H2-type zinc finger domains. Through whole-mount in situ hybridization, we found that znf219L mRNA is mainly expressed in the zebrafish midbrain-hindbrain boundary, hindbrain, and notochord during development. The znf219L morpholino knockdown caused partial abnormal notochord phenotype and reduced expression of endogenous col2a1a in the notochord specifically. In addition, ZNF219L could recognize binding sites with GGGGG motifs and trigger augmented activity of the col2a1a promoter in a luciferase assay. Furthermore, in vitro binding experiments revealed that ZNF219L recognizes the GGGGG motifs in the promoter region of the zebrafish col2a1a gene through its sixth and ninth zinc finger domains. Taken together, our results reveal that ZNF219L is involved in regulating the expression of col2a1a in zebrafish notochord specifically.     

巨细胞病毒参与动脉粥样硬化致病机制研究新进展

人巨细胞病毒(human cytomegalovirus, HCMV)是β疱疹病毒家族成员,在人群中感染率极高,全球成人中血清阳性率可达40%～100%。研究表明,HCMV感染患者更易患心脑血管疾病。动脉粥样硬化(atherosclerosis,AS)是心血管系统疾病中危害健康的一种常见病。大量流行病学研究证明,在AS组织中可检测出较高的HCMV DNA和抗原、抗体,同时回顾性研究发现AS患者多有HCMV暴露因素,提示HCMV可能参与AS致病。本文就HCMV致AS的依据和机制进行综述, 为研究HCMV在AS病理过程中的作用提供全新视角。     

Phosphorylation of ganciclovir phosphonate by cellular GMP kinase determines the stereoselectivity of anti-human cytomegalovirus activity

A racemic mixture of ganciclovir phosphonate was resolved by stereoselective phosphorylation using GMP kinase. The R-enantiomer of ganciclovir phosphonate was active against human cytomegalovirus but the S-enantiomer was less active. We show that enantiomeric selectivity of antiviral for ganciclovir phosphonate was conferred by stereoselective phosphorylations by mammalian enzymes, not by stereoselective inhibition of DNA polymerase from human cytomegalovirus.     

Design and synthesis of a potent macrocyclic 1,6-naphthyridine anti-human cytomegalovirus (HCMV) inhibitors

A novel class of macrocyclic 1,6-napthyridines designed to adopt the presumed bioactive conformation of anti-HCMV acyclic 1,6-napthyridines are described. Both 14- and 15-membered macrocycles were shown to be highly potent against HCMV HSV-1 and HSV-2.     

lncRNA MEG3 modified epithelial-mesenchymal transition of ovarian cancer cells by sponging miR-219a-5p and regulating EGFR

This study was aimed to verify whether there existed any associations between long noncoding RNA MEG3/miR-219a-5p/EGFR axis and the development of ovarian cancer (OC). As a whole, we gathered 317 pairs of OC tissues and surgical marginal normal tissues and simultaneously acquired four OC cell lines (ie, A2780, Caov-3, OVCAR-3, and SKOV-3) and human normal ovarian surface epithelial cell line. Moreover, pcDNA3.1-MEG3, si-MEG3, miR-219a-5p mimic, miR-219a-5p inhibitor, pcDNA3.1-EGFR, and si-EGFR were, respectively, transfected into the OC cells, and their impacts on viability, proliferation, apoptosis, invasion, and migration of OC cells were assessed via conduction of MTT assay, colony formation assay, flow cytometry assay, transwell assay, and scratch assay. Ultimately, dual-luciferase reporter gene assay was performed to testify the targeted relationships among maternally expressed gene 3 (MEG3), miR-219a-5p, and estimated glomerular filtration rate (EGFR). It was indicated that underexpressed MEG3 and miR-219a-5p were significantly associated with unfavorable prognosis of patients with OC when compared with overexpressed MEG3 and miR-219a-5p (P < .05). In addition, the OC cells transfected with si-MEG3 or miR-219a-5p inhibitor exhibited stronger viability, proliferation, invasion, and migration than untreated cells (P < .05). Correspondingly, the apoptotic percentage of OC cells was reduced observably under treatments of si-MEG3 and miR-219a-5p inhibitor (P < .05). Moreover, MEG3 exerted modulatory effects on the expression of miR-219a-5p (P < .05), and there was a sponging relationship between them (P < .05). Finally, EGFR expression was modified by both MEG3 and miR-219a-5p significantly (P < .05), and raising EGFR expression could changeover the impacts of MEG3 and miR-219a-5p on the above-mentioned activity of OC cells (P < .05). Conclusively, MEG3 could serve as a promising biomarker for diagnosis and treatment of OC, considering its involvement with OC etiology via regulation of miR-219a-5p/EGFR axis.     

假单胞菌YL11对扩展青霉的抑制作用及其机理初探

【背景】苹果青霉病是由扩展青霉引起的一种重要的果实采后病害,影响果实品质导致苹果腐烂从而造成经济损失。【目的】研究假单胞菌YL11对扩展青霉的抑制作用和苹果采后青霉病的防治效果,并对抑菌机理进行初步探讨。【方法】以扩展青霉为供试菌株,研究不同浓度的假单胞菌YL11无菌发酵液对扩展青霉菌落直径、孢子萌发率、菌丝体干重、苹果损伤接种病斑直径扩展的影响,利用对电导率、核酸及蛋白释放量、AKP含量、SDH活性、ATP酶活性和ATP含量的影响对抑菌机理进行探究。【结果】假单胞菌YL11无菌发酵液能有效抑制扩展青霉生长,抑菌圈直径为22.33±0.27 mm,抑菌效价为71.67 mm/mL;能有效抑制孢子萌发,100%无菌发酵液对孢子萌发抑制率达到80.2%;对扩展青霉的生物量也有一定抑制作用,体积分数为100%时,菌丝体干重为4.7mg/mL,抑制率达到39.74%;无菌发酵液处理能有效抑制苹果青霉病病斑的扩展,3d时对病斑扩展的抑制率最大,达到47.1%;无菌发酵液处理均能引起电导率升高、胞内核酸和蛋白释放量增大、胞外AKP含量升高、SDH活性降低、ATP酶活性和ATP含量均降低,且随着发酵液浓度的增加效果越明显。【结论】假单胞菌YL11能显著抑制扩展青霉的生长,破坏细胞膜结构、降低能量代谢酶活性,从而扰乱扩展青霉的正常生长,对苹果青霉病有较好的生防效果,具有潜在的开发价值。     

Endometriosis; a clinical and pathological study of 219 cases

The traditional treatment of needling or discission of congenital cataract or membrane is open to many serious objections. Removal of the cataract by a modified form of linear extraction is recommended. The technique, with recent improvements which further assure extraction without hazard in early infancy, is described.