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101.
摘要 目的:揭示miR-455-5p对呼吸道合胞病毒(RSV)感染致气道上皮细胞炎症反应的作用机制。方法:qRT-PCR检测30例健康体检儿童(健康组)、RSV感染轻症组(n=41)和重症组(n=31)患儿血清miR-455-5p水平。将16HBE细胞分为Control组、NC-agomir组、miR-455-5p-agomir组、NC-antagomir组、miR-455-5p-antagomir组。使用Lipofectamine 3000转染16HBE细胞后培养48 h后,分为Blank组、NC组(转染了NC-agomir的细胞)、RSV+NC-agomir组、RSV+miR-455-5p-agomir组,用RSV病毒液感染RSV+NC-agomir组和RSV+miR-455-5p-agomir组16HBE细胞,Blank组和NC组16HBE细胞正常培养。用CCK-8法和EdU法检测细胞增殖、TUNEL法检测细胞凋亡、ELISA法检测上清液中TNF-α、IL-6、IL-8水平,qRT-PCR检测miR-455-5p和SOCS3的mRNA水平,Western blot检测SOCS3、IFN-α、STAT1、STAT2、p-STAT1和p-STAT2的蛋白水平。结果:与健康组相比,轻症组和重症组患儿的血清miR-455-5p水平降低(P<0.05)。与轻症组相比,重症组的血清miR-455-5p水平降低(P<0.05)。与Control组和NC-agomir组相比,miR-455-5p-agomir组16HBE细胞的miR-455-5p水平、相对细胞活力和EdU阳性率升高(P<0.05),TUNEL阳性率降低(P<0.05),上清液中的TNF-α、IL-6和IL-8水平降低(P<0.05),SOCS3 mRNA和蛋白水平降低(P<0.05),IFN-α蛋白、STAT1和STAT2磷酸化水平升高(P<0.05)。与Control组和NC-antagomir组相比,miR-455-5p-antagomir组16HBE细胞的miR-455-5p水平、相对细胞活力和EdU阳性率降低(P<0.05),TUNEL阳性率升高(P<0.05),上清液中的TNF-α、IL-6和IL-8水平升高(P<0.05),SOCS3 mRNA和蛋白水平升高(P<0.05),IFN-α蛋白、STAT1和STAT2磷酸化水平降低(P<0.05)。与Blank组和NC组相比,RSV+NC-agomir组16HBE细胞的miR-455-5p水平、相对细胞活力和EdU阳性率降低(P<0.05),TUNEL阳性率升高(P<0.05),上清液中的TNF-α、IL-6和IL-8水平升高(P<0.05),SOCS3 mRNA和蛋白水平升高(P<0.05),IFN-α蛋白、STAT1和STAT2磷酸化水平降低(P<0.05)。与RSV+NC-agomir组相比,RSV+miR-455-5p-agomir组的miR-455-5p水平、相对细胞活力和EdU阳性率升高(P<0.05),TUNEL阳性率降低(P<0.05),上清液中的TNF-α、IL-6和IL-8水平降低(P<0.05),SOCS3 mRNA和蛋白水平降低(P<0.05),IFN-α蛋白、STAT1和STAT2磷酸化水平升高(P<0.05)。结论:miR-455-5p在RSV感染患儿血清中下调,上调miR-455-5p通过抑制SOCS3的转录和表达从而激活RSV感染的16HBE细胞中IFN-α介导的抗病毒反应。 相似文献
102.
摘要 目的:探讨血清微小核糖核酸(miRNA)-141-3p、miR-150-5p与鼻咽癌(NPC)患者临床病理特征和放疗敏感性的关系。方法:收集2019年1月~2022年7月在我院接受放疗的92例NPC患者为NPC组,根据放疗疗效分为抵抗组和敏感组,另选取同期80名在我院体检的健康志愿者为对照组。比较对照组、NPC组血清miR-141-3p、miR-150-5p表达。分析NPC患者血清miR-141-3p、miR-150-5p表达与临床病理特征的关系。利用单因素和多因素Logistic回归分析NPC患者放疗抵抗的影响因素。结果:与对照组比较,NPC组血清miR-141-3p表达升高,miR-150-5p表达降低(P<0.05)。NPC患者血清miR-141-3p、miR-150-5p表达在不同分化程度、TNM分期和淋巴结转移中比较有差异(P<0.05)。92例NPC患者放疗抵抗发生率为22.83%(21/92)。单因素分析显示,抵抗组TNM分期Ⅲ~Ⅳa期和miR-141-3p ≥ 2.60比例高于敏感组,miR-150-5p ≥ 0.80比例低于敏感组(P<0.05)。多因素Logistic回归分析显示,miR-141-3p ≥ 2.60为NPC患者放疗抵抗的独立危险因素,miR-150-5p ≥ 0.80为独立保护因素(P<0.05)。结论:NPC患者血清miR-141-3p高表达,miR-150-5p低表达,与分化程度、TNM分期、淋巴结转移和放疗敏感性有关,有望成为NPC患者放疗抵抗的评价指标。 相似文献
103.
摘要 目的:研究甲状腺乳头状癌(PTC)组织微小核糖核酸-93-5p(miR-93-5p)、微小RNA-98-5p(miR-98-5p)表达与临床病理特征和增殖、侵袭基因表达的关系。方法:选取2020年10月到2023年10月在广东省中医院行手术切除的PTC患者153例作为研究对象,收集术中切除的癌组织以及癌旁组织。检测并比较癌组织与癌旁组织miR-93-5p、miR-98-5p及增殖基因、侵袭基因mRNA表达水平,分析miR-93-5p及miR-98-5p表达与PTC患者临床病理特征的关系。利用Pearson法分析miR-93-5p、miR-98-5p表达水平与增殖基因、侵袭基因mRNA表达的相关性。结果:癌组织的miR-93-5p表达水平较癌旁组织更高,miR-98-5p表达水平较癌旁组织更低(P<0.05)。miR-93-5p高表达PTC患者TNM分期Ⅲ~Ⅳ期、有淋巴结转移及低分化的比例较miR-93-5p低表达PTC患者更高(P<0.05)。miR-98-5p低表达PTC患者TNM分期Ⅲ~Ⅳ期、有淋巴结转移及低分化的比例较miR-98-5p高表达PTC患者更高(P<0.05)。癌组织的增殖基因程序性细胞死亡因子4(PDCD4)及蛋白磷酸酶4调节亚基 (PP4R1)水平较癌旁组织更低(P<0.05),侵袭基因金属蛋白酶解离素9(ADAM9)及Bcl-6共抑制因子样蛋白(BCORL1)水平较癌旁组织更高(P<0.05)。Pearson法分析结果显示,miR-93-5p表达与增殖基因PDCD4及PP4R1表达水平呈负相关,与侵袭基因ADAM9及BCORL1表达水平呈正相关。miR-98-5p表达水平与增殖基因PDCD4及PP4R1水平呈正相关,与侵袭基因ADAM9及BCORL1表达水平呈负相关。结论:PTC患者癌组织miR-93-5p表达升高,miR-98-5p表达降低,与TNM分期、淋巴结转移及分化程度等临床病理特征有关,还可促进PTC癌细胞增殖、侵袭。 相似文献
104.
《Bioscience, biotechnology, and biochemistry》2013,77(10):2226-2232
A novel membrane protein, Yml067c in the systematic ORF name, was discovered as a component of immunoisolated vesicles of the early Golgi compartment of the yeast Saccharomyces cerevisiae (Cho et al., FEBS Lett. 469, 151-154 (2000)). Conserved sequences having sequence similarity to Yml067c were widely distributed in the eukaryotes and one of them, Yal042w, was found in the Saccharomyces genome database. In the yeast cell, Yml067c and Yal042w were found to form a heterooligomeric complex by immunoprecipitation of their tagged derivatives from the detergent-solubilized membrane. Cell fractionation and indirect immunofluorescent staining indicated that the majority of these proteins were localized on the ER membrane. Therfore, the Yml067c-Yal042w complex should shuttle between the ER and the early Golgi compartment as well as the p24-family proteins. 相似文献
105.
A direct method for determination of Δ5 3β-hydroxysteroid dehydrogenase (3β-HSD) activity was employed in isolated Leydig cells (LC) derived from rats on fetal day 19 (F19) and postnatal (N) days 1,12,24, 34 and 45 and adults. The activity of 3β-HSD in the adult LC was 1.15 ± 0.02 (μmole/μg DNA/hr, mean ± SEM, n = 73). Activities in the other groups, expressed as a percentage of the respective adult control, were: F19-38%; N1-39%; N12-8%; N24-89%; N34-166%; and N45-118%. A good correlation was found between histochemical staining for 3β-HSD and the quantitive method employed. Using (3H)-DHA as a substrate, LC isolated from F19, n1 and N12 produced testosterone in appreciable amounts (41%, 55% and 20% of the toal products respectively) whereas at advanced stages of development (N24 to adulthood) the major product was androstenedione (93 ± 1%). These findings may be explained by the observed decrease in 17β-hydroxysteroid dehydrogenase (17β-HSD) activity, due to an insufficient supply of NADPH, in the older vs. earlier stages of development. This study indicates the presence of steroidogenic enzymatic activity in LC throughout development in the rat. It also provides a relatively simple in vitro model for studies of testicular regulation during development. 相似文献
106.
Zabotina OA van de Ven WT Freshour G Drakakaki G Cavalier D Mouille G Hahn MG Keegstra K Raikhel NV 《The Plant journal : for cell and molecular biology》2008,56(1):101-115
The function of a putative xyloglucan xylosyltransferase from Arabidopsis thaliana (At1g74380; XXT5) was studied. The XXT5 gene is expressed in all plant tissues, with higher levels of expression in roots, stems and cauline leaves. A T-DNA insertion in the XXT5 gene generates a readily visible root hair phenotype (root hairs are shorter and form bubble-like extrusions at the tip), and also causes the alteration of the main root cellular morphology. Biochemical characterization of cell wall polysaccharides isolated from xxt5 mutant seedlings demonstrated decreased xyloglucan quantity and reduced glucan backbone substitution with xylosyl residues. Immunohistochemical analyses of xxt5 plants revealed a selective decrease in some xyloglucan epitopes, whereas the distribution patterns of epitopes characteristic for other cell wall polysaccharides remained undisturbed. Transformation of xxt5 plants with a 35S::HA-XXT5 construct resulted in complementation of the morphological, biochemical and immunological phenotypes, restoring xyloglucan content and composition to wild-type levels. These data provide evidence that XXT5 is a xyloglucan alpha-1,6-xylosyltransferase, and functions in the biosynthesis of xyloglucan. 相似文献
107.
Human p38 mitogen-activated protein kinase inhibitor drugs inhibit Plasmodium falciparum replication
Brumlik MJ Nkhoma S Kious MJ Thompson GR Patterson TF Siekierka JJ Anderson TJ Curiel TJ 《Experimental parasitology》2011,128(2):170-175
We recently demonstrated that human p38 mitogen-activated protein kinase (MAPK) inhibitors reduced in vitro and in vivo replication of the protozoan parasites Toxoplasma gondii and Encephalitozoon cuniculi. In this study, we assessed the efficacy of five p38 MAPK inhibitors to block the replication of Plasmodium falciparum in human erythrocytes cultured ex vivo and demonstrate that the pyridinylimidazole RWJ67657 and the pyrrolobenzimidazole RWJ68198 reduced P. falciparum replication, yielded trophozoites that were greatly diminished in size at 24 h, and that these two agents interfered with stage differentiation. Interestingly, the chloroquine-resistant strain W2 was significantly more sensitive to these drugs than was the chloroquine-sensitive strain HB3. These results suggest that pyridinylimidazoles and pyrrolobenzimidazoles designed to inhibit human p38 MAPK activation can be developed to treat malaria. 相似文献
108.
I. O. Vassilieva Yu. A. Negulyaev I. I. Marakhova S. B. Semenova 《Cell and Tissue Biology》2008,2(6):584-589
The recent cloning of the special calcium channels TRPV5 and TRPV6 (transient receptor potential vanilloid channels) has provided a molecular basis for studying previously unidentified calcium influx channels in electrically nonexcitable cells. In the present work using RT-PCR, we obtained the endogenous expression of mRNAs of genes trpv5 and trpv6 in lymphoblast leukemia Jurkat cells and in normal human T lymphocytes. Additionally, by immunoblotting, the presence of the channel-forming TRPV5 proteins has been shown both in the total lysate and in crude membrane fractions from Jurkat cells and normal T lymphocytes. The use of immunoprecipitation revealed TRPV6 proteins in Jurkat cells, whereas in normal T lymphocytes, this protein was not detected. The expression pattern and the selective Ca2+ permeation properties of TRPV5 and TRPV6 channels indicate the important role of these channels in Ca2+ homeostasis, as well as most likely in malignant transformation of blood cells. 相似文献
109.
N E Owen 《Biochemical and biophysical research communications》1984,125(2):500-508
The regulation of Na/K/Cl cotransport was investigated in vascular smooth muscle cells. That a Na/K/Cl cotransport system exists was established by the finding that the ouabain insensitive K influx was sensitive to the "loop" diuretic bumetanide. Furthermore, bumetanide sensitive K influx was dependent upon the presence of both Na and Cl in the extracellular milieu. Bumetanide sensitive K influx was inhibited by agents which elevate cellular cyclic AMP levels, and to a lesser extent by agents which elevate cellular cyclic GMP levels. When serum, EGF or TPA was added, bumetanide sensitive K influx was enhanced. These results suggest that vascular smooth muscle cells have a ouabain insensitive, bumetanide sensitive Na/K/Cl cotransport system which is stimulated by serum, EGF or TPA and inhibited by cAMP or cGMP. 相似文献
110.
D. -L. Wei S. -C. Chang Y. -H. Wei Y. -W. Lin C. -L. Chuang S. -C. Jong 《World journal of microbiology & biotechnology》1992,8(2):141-146
Eighteen strains of xylariaceous fungi have been screened for higher activities of cellulolytic enzymes,Trichoderma reesei QM 9414 was also examined for comparison. Strains ofXylaria anisopleura andX. regalis had higher endocellulase (CMCase) and exocellulase (Avicelase) activities after 2 weeks' incubation.Hypoxylon stygium produced the highest activity of -glucosidase 3 days after inoculation. The optimum pH for these cellulolytic enzymes was approx. 5.0 and the optimum temperatures ranged from 37 to 50°C. A mixed culture process usingT. reesei QM 9414 andH. stygium was developed to obtain enhanced synthesis of cellulase. -Glucosidase activities in the mixed culture increased within 48h whenH. stygium was introduced after 24h. 相似文献