Hsa-miR-5195-3p对人宫颈癌细胞SiHa增殖、迁移与侵袭的影响

目的:探讨mi R-5195-3p对人宫颈癌细胞系Si Ha增殖、迁移与侵袭的影响。方法:采用qRT-PCR检测人宫颈癌细胞SiHa和正常上皮细胞HaCaT中mi R-5195-3p的表达水平。将mi R-5195-3p mimic转染至Si Ha细胞中构建外源性过表达细胞株,阴性对照组中则转染NC mimic,并用q RT-PCR验证转染效率;通过MTT和集落形成实验检测细胞增殖能力;划痕愈合实验检测细胞横向迁移能力; Transwell小室实验检测细胞纵向迁移能力和侵袭能力;采用qRT-PCR和Western blot检测E-cadherin、Vimentin与snail m RNA转录水平及蛋白表达水平。结果:宫颈癌细胞Si Ha中的mi R-5195-3p表达水平较HaCaT偏低(P 0. 05)。与阴性对照组相比,转染mi R-5195-3p mimic的SiHa细胞中mi R-5195-3p水平显著增高(P 0. 01);并且其体外增殖(P 0. 001),迁移(P 0. 001)与侵袭能力(P 0. 001)明显减弱;同时E-cadherin表达水平上调而Vimentin、snail表达水平下调。结论:过表达mi R-5195-3p可能通过阻碍EMT通路抑制宫颈癌细胞Si Ha的增殖,迁移与侵袭。     

miR-195-5p在结直肠癌和肺癌细胞中的功能差异性研究

目的:分析miR-195-5p在结直肠癌和肺癌组织及相应肿瘤细胞中的表达差异和功能差异。方法:通过starBase数据库调取癌症基因组图谱(TCGA)中miR-195-5p表达数据,分析其在结直肠癌和肺癌组织中的表达差异;采用人结直肠癌细胞系SW620、小鼠结直肠癌细胞系MC38、人肺癌细胞系A549和小鼠肺癌细胞系344SQ进一步分析miR-195-5p在不同肿瘤细胞中的表达差异;采用CCK-8法检测miR-195-5p过表达对SW620和A549细胞增殖的影响;采用Transwell实验检测mi R-195-5p过表达对SW620和A549细胞侵袭与迁移能力的调控差异。结果:生物信息学分析结果显示miR-195-5p在结直肠癌组织中显著高表达,而在肺癌组织中的表达量却低于正常对照;与组织表达结果类似,结直肠癌细胞中miR-195-5p的表达量显著高于肺癌细胞;过表达miR-195-5p抑制人肺癌细胞A549的增殖、迁移与侵袭,而在人结直肠癌细胞SW620中结果却截然相反。结论:miR-195在不同类型的肿瘤中表达不同,功能也存在差异,不能简单地概括为一种抑癌因子或致癌因子,miR-195在肿瘤中的作用仍有待进一步研究。     

miR-382-3p靶向RASA1基因调控骨关节炎软骨细胞增殖和凋亡

目的:探讨mi R-382-3p对骨关节炎软骨细胞增殖和凋亡的影响及其机制。方法:用100 ng/mL的脂多糖(LPS)处理软骨细胞,记为LPS组,以正常培养的软骨细胞作为正常对照(NC)组。mi R-NC、mi R-382-3p、anti-miR-NC、anti-miR-382-3p转染至软骨细胞中,记为mi R-NC组、mi R-382-3p组、anti-miR-NC组、anti-miR-382-3p组;将mi R-NC、mi R-382-3p、si-NC、si-RASA1转染至软骨细胞后再用100 ng/mL的LPS处理,记为mi R-NC+LPS组、mi R-382-3p+LPS组、si-NC+LPS组、si-RASA1+LPS组;将mi R-382-3p分别与pcDNA-NC、pcDNA-RASA1共转染至软骨细胞后再用100 ng/mL的LPS处理,记为mi R-382-3p+pcDNA-NC+LPS组、mi R-382-3p+pcDNA-RASA1+LPS组。实时荧光定量PCR(RT-qPCR)检测mi R-382-3p和Ras p21蛋白活化因子1(RASA1)m RNA表达水平;蛋白质印迹(Western blot)法检测RASA1、细胞周期蛋白D1(CyclinD1)、裂解的半胱氨酸天冬氨酸蛋白酶-3(Cleaved-caspase-3)蛋白表达;四甲基偶氮唑盐比色法(MTT)检测细胞存活率;流式细胞术检测细胞凋亡;荧光素酶报告实验检测mi R-382-3p和RASA1的靶向关系。结果:LPS诱导的软骨细胞中mi R-382-3p表达水平显著降低,RASA1表达水平显著升高,CyclinD1表达水平显著降低,Cleaved-caspase-3表达水平显著升高,细胞存活率显著降低,细胞凋亡率显著升高(P0.05)。过表达mi R-382-3p和敲减RASA1,LPS诱导的软骨细胞中CyclinD1表达水平显著升高,Cleaved-caspase-3表达水平显著降低,细胞存活率显著升高,细胞凋亡率显著降低(P0.05)。mi R-382-3p靶向调控RASA1,高表达RASA1部分逆转了mi R-382-3p高表达对LPS处理的软骨细胞增殖和凋亡的影响。结论:过表达mi R-382-3p促进软骨细胞增殖,抑制LPS诱导的软骨细胞凋亡,其机制可能与RASA1有关。     

miR-31-3p对横纹肌肉瘤细胞增殖和迁移的抑制作用和机制

该文研究了micro RNA-31-3p(mi R-31-3p)在横纹肌肉瘤细胞中的表达水平及其对细胞增殖和迁移的影响。通过定量RT-PCR法检测mi R-31-3p的表达水平。采用脂质体介导法将mi R-31-3p成熟体转染入横纹肌肉瘤细胞,通过MTS法、克隆形成实验、流式细胞技术和细胞功能分析仪分别检测细胞增殖能力、生长能力、周期和迁移能力。萤光素酶法和Western blot验证mi R-31-3p的靶基因。通过si RNA抑制STAT3检测其对横纹肌肉瘤细胞增殖和迁移的影响。结果显示,横纹肌肉瘤细胞中mi R-31-3p的表达水平较正常横纹肌组织显著下调。上调横纹肌肉瘤细胞中的mi R-31-3p能显著抑制细胞的增殖、克隆形成和迁移能力,并诱导细胞周期发生G1期阻滞。萤光素酶和Western blot结果显示, STAT3为mi R-31-3p的靶基因。下调STAT3的表达水平能够显著抑制RD细胞的增殖和迁移能力。总之, miR-31-3p可能通过下调STAT3来抑制横纹肌肉瘤细胞增殖和迁移。     

miR-223在结肠癌组织中的表达及促进结肠癌细胞迁移侵袭的机制研究

目的:探讨微小RNA-223 (mi R-223)在结肠癌组织中的表达及对结肠癌HT-29细胞侵袭、迁移能力的影响及机制。方法:检测mi R-223在结肠癌组织与癌旁组织中的表达。通过脂质体转染法将mi R-223模拟物(mi R-223 mimics,mi R-223 mimics组)及microRNA无关序列(mi R-223 NC,NC组)转染入结肠癌HT-29细胞。采用Real-time PCR检测转染后细胞中mi R-223和TWIST的表达,Western blot检测TWIST的蛋白表达,Tranwell检测细胞的迁移与侵袭能力。双荧光素酶报告基因检测mi R-223对TWIST基因启动子活性的影响。采用Transwell迁移与侵袭实验检测mi R-223 mimic及Twist si RNA共转染后人结肠癌细胞系HT-29迁移与侵袭能力的变化。结果:与癌旁结肠组织比较,mi R-223在结肠癌组织中呈现明显高表达(P0.05);与空白对照组和mi R-223 NC组比较,转染mi R-223 mimics后的HT-29细胞中的mi R-223表达显著增加(P0.05)。与阴性对照组和空载转染组相比较,mi R-223 mimics转染组穿透的细胞数目明显增加(P0.05),且mi R-223 mimics转染组的细胞侵袭能力显著增强(P0.05)。与mi R-223 NC组和空白对照组比较,转染mi R-223 mimics的HT-29细胞的TWIST基因m RNA和蛋白表达均显著增加(P0.05)。双荧光素酶检验结果显示TWIST为mi R-223的下游靶基因。共转染TWIST si RNA和mi R-223 mimics的结肠癌HT-29细胞的迁移与侵袭能力较单独转染mi R-223 mimics的HT-29细胞显著减弱(P0.05)。结论:mi R-223可能通过上调下游靶基因TWIST水平促进结肠癌HT-29细胞的迁移与侵袭。     

miR-369-3p靶向FGF9信号通路调控肝癌细胞增殖与侵袭

目的:阐明脂代谢相关mi R-369-3p在肝癌(hepatocellular carcinoma, HCC)病理组织中的表达特征及其与临床预后的相关性,解析mi R-369-3p在HCC细胞中的作用性质及相应分子机理。方法:实时定量PCR法检测mi R-369-3p在HCC病理组织和细胞中的表达变化,并通过Spearman's法分析mi R-369-3p表达水平与临床病理资料相关性;CCK-8检测、Transwell穿透小室实验和裸鼠荷瘤实验检测敲低内源性mi R-369-3p表达后对HCC细胞增殖和侵袭性的影响作用;利用生物信息学分析、瞬时转染、定点突变和荧光素酶报告基因活性检测分析mi R-369-3p对纤维母细胞生长因子9(fibroblast growth factor 9,FGF9)的转录后调控作用。结果:mi R-369-3p在HCC病理组织(n=68)和细胞中异常低表达,且此低表达趋势与HCC患者预后呈显著负相关关系(x~2=6.907,P=0.0086);敲低内源性mi R-369-3p可显著促进HCC细胞的增殖、侵袭性;参与调控这一抑瘤效应的关键分子机制可能是miR-369-3p与FGF9的3'-UTR区直接结合,在转录后水平抑制FGF9 m RNA的稳定性,进而抑制后者表达水平。结论:miR-369-3p可通过靶向FGF9信号在转录后调控水平负性调控肝癌细胞增殖和侵袭过程,在肝癌发生和进展过程中发挥关键抑癌作用。     

miR-345靶向调控 TGM1抑制膀胱癌的初步研究

目的:探讨mi R-345调控TGM1表达影响膀胱癌的分子生物学机制。方法:首先,采用RT-qPCR检测T24和RT4细胞中mi R-345、TGM1的表达;再采用mi RNA-NC、mi R-345 mimic、NC inhibitor、mi R-345 inhibitor、control si RNA、si TGM1和pc-DNA3.1/TGM1等转染膀胱癌细胞;然后,采用MTT实验检测细胞增殖,Transwell实验检测细胞侵袭,流式细胞仪检测细胞凋亡,双荧光报告酶检测mi R-345的靶基因;最后,采用Western blot检测TGM1在细胞中的表达。结果:mi R-345在T24和RT4细胞中表达低于正常细胞(P0.05)。mi R-345过表达时,T24和RT4细胞的增殖侵袭能力减弱,细胞凋亡率上升;mi R-345表达沉默时,细胞增殖和侵袭能力增强,细胞凋亡率下降。双荧光报告基因检测结果显示TGM1为mi R-345的靶基因,mi R-345过表达抑制TGM1的表达(P0.05);mi R-345表达沉默时则表达上调(P0.05)。当TGM1表达沉默时,T24和RT4细胞的增殖和侵袭能力减弱,细胞凋亡率上升;TGM1过表达时该细胞的增殖和侵袭能力增强,细胞凋亡率下降。结论:mi R-345通过下调靶基因TGM1的表达,抑制膀胱癌细胞的增殖、侵袭并促进细胞凋亡。     

ATAD3A在结直肠癌组织中的表达及其对细胞生长的影响

目的:探讨三磷酸腺苷酶家族蛋白3A(ATAD3A)在结直肠癌组织中的表达情况,并验证其对结直肠癌细胞RKO和HCT116生长的影响。方法:收集结直肠癌患者配对癌与癌旁组织115例,通过免疫组化方式验证ATAD3A在结直肠癌组织与癌旁的表达差异。采用慢病毒转染和si-RNA干涉的方式构建ATAD3A过表达和敲低肠癌细胞系,并采用MTS,流式检测细胞周期和细胞凋亡等方法验证ATAD3A对结直肠癌细胞系RKO和HCT116的影响。结果:ATAD3A在结直肠癌组织中表达较癌旁组织显著升高(P0.001)。在结直肠癌细胞系RKO和HCT116中过表达ATAD3A后,细胞增殖能力明显增强,处于S期的细胞比例明显增加,而且细胞凋亡数量明显减少。反之,在上述肠癌细胞中干涉ATAD3A后,细胞增殖能力减弱,细胞大部分停滞于G1期,而且凋亡细胞数量明显增多。结论:ATAD3A在结直肠癌组织中表达升高,且ATAD3A通过促进细胞增殖、细胞周期进程和抑制细胞凋亡等方式促进肠癌细胞的生长。     

miR-153-5p靶向SNAI1介导结直肠癌细胞的放疗抵抗

目的 探讨miR-153-5p在结直肠癌放疗抵抗中的作用,并进一步研究其潜在分子机制。方法 首先对放疗敏感细胞系SW480及放疗抵抗结直肠癌细胞系SW480R中miR-153-5p表达水平进行RT-qPCR检测;然后利用转染技术构建过表达miR-153-5p的SW480R细胞株,检测过表达miR-153后SW480R在接受放射后其细胞活力、侵袭能力、集落形成能力、凋亡水平的改变;免疫组织化学染色观察放疗敏感及放疗抵抗结直肠癌组织中SNAI1的表达差异;TargetScan分析miR-153-5p潜在靶点并利用荧光素酶实验验证;检测过表达miR-153-5p及SNAI1后SW480R细胞侵袭能力、集落形成能力及凋亡水平。结果 与SW480组相比,SW480R组细胞中miR-153-5p表达降低;过表达miR-153-5p的SW480R细胞细胞活力、侵袭能力、集落形成能力均明显减弱,而凋亡水平显著增加;与放疗敏感结直肠癌组织相比,放疗抵抗结直肠癌组织中SNAI1显著增加;SNAI1可能为miR-153-5p的作用靶点;过表达miR-153-5p及SNAI1后SW480R细胞侵袭能力、集落形...     

miR-155对人肝癌细胞系SK-HEP-1及MHCC-97H增殖与浸润能力的影响

目的:在肝癌细胞系SK-HEP-1及MHCC-97H中过表达mi R-155,研究其对肝癌细胞增殖能力的影响。方法:将pc DNA3.0-mi R-155表达载体瞬时转染SK-HEP-1及MHCC-97H肝癌细胞系,通过实时定量PCR技术检测mi R-155在转录水平的表达;采用CCK8法及克隆形成实验检测mi R-155过表达后对SK-HEP-1及MHCC-97H肝癌细胞系增殖的影响;采用Transwell实验探讨mi R-155过表达后对肿瘤细胞浸润能力的影响。结果:实时定量PCR检测结果显示,转染SK-HEP-1及MHCC-97H细胞后72 h,成熟mi R-155表达分别上调约424±48.5倍及63.69±7.8倍,表明mi R-155在肿瘤细胞内得到高表达;CCK8法及克隆形成实验结果显示,mi R-155能够明显促进肝癌细胞增殖(P0.01);Transwell实验证明mi R-155明显促进MHCC-97H肿瘤细胞的浸润能力。结论:mi R-155在肝癌细胞中的高表达能够明显促进肝癌细胞增殖与浸润,提示其有可能在肝癌的发生发展中发挥重要作用。     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.     

Composition and diversity of bird communities in Swedish farmland–forest mosaic landscapes

CapsuleThe amount of forest (at local and landscape scales) and occurrence of residual habitats at the local scale are shown to be the major factors influencing bird community composition in farmland–forest landscapes in central Sweden.

Aims To investigate the importance of local habitat and landscape structure for breeding birds in farmland–forest landscapes in central Sweden.

Methods Breeding birds were censused at 292 points. A detailed habitat mapping was made within 300 m of the points. Within a 300–600 m radius only two major habitats (forests and arable fields) were identified.

Results Cluster analyses of bird communities identified three site types that also differed in habitat composition: (i) partially forested sites in forested landscapes; (ii) heterogeneous sites with residual habitats in mosaic landscapes; and (iii) field-dominated farmland sites in open landscapes. A total of 19 of 25 farmland bird species (restricted to farmland or using both farmland and forest) had the highest abundance in farmland sites with mosaics of forest and farmland, while only six farmland species had the highest abundance in field-dominated sites. The bird community changed from being dominated by farmland species to being dominated by forest species (common in forest landscapes without farmland) at small proportions (10–20%) of forest at the local scale. A major difference in habitat composition between heterogeneous and field-dominated sites was the occurrence of different residual habitats (e.g. shrubby areas and seminatural grasslands). These habitats seemed to influence bird community composition more than land-use, despite covering <10% of the area. Seminatural grasslands were important for bird community composition and species-richness, but grazing seemed to be less important. Among different land-use types, cereal crops were the least preferred fields. Set-asides with tall vegetation and short rotation coppices were positively associated with species-richness of farmland birds.

Conclusion In general, the composition of the landscape was important for bird community composition, although amount and distribution of forests, occurrence of residual habitats and land-use of fields at the local scale had the strongest influence on bird community composition. The possible implications of these patterns for managing farmland–forest landscapes are discussed.     

Chemical constituents from the fruits of Rhus typhina L. and their chemotaxonomic significance

This work describes the isolation and characterization of twenty-nine compounds from the fruits of Rhus typhina L., including eleven flavonoids (1–11), eleven phenols (12–22), two pentacyclic triterpenes (23–24), two organic acids (25–26), one lumichrome (27), one courmarin (28) and one pyrimidine (29) on the basis of their spectroscopic data. Compounds apigenin (1), daidzein (4), orobol (5), 3′, 5, 5′, 7-tetrahydroxyflavanone (6), naringenin (7), butein (8), (-)-catechin (9), quercetin-3-O-α-L-(3″-O-galloyl)-rhamnoside (11), 2-hydroxybenzoic acid (13), 4-hydroxybenzaldehyde (14), vanillin (15), methyl 3,4-dihydroxybenzoate (16), 3,5-dihydroxybenzamide (18), tyrosol (19), caffeic acid (20), 3-(2,4,6-trihydroxyphenyl)-1-(4-hydroxyphenyl)-propan-1-one (21), phlorizin (22), friedelin (23), oleanolic acid (24), 4,4-dimethyl-heptanedioic acid (25), anthranilic acid (26), lumichrome (27), scoparone (28) and uracil (29) have not been recorded before in this plant. This is the first report on the occurrence of compounds 4–7, 9, 11, 13–14, 16, 18–21, 25–29 from the genus Rhus. Moreover, the chemotaxonomic significance of these isolated compounds was also summarized.