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991.
Yuet-Kin Leung Bin Ouyang Liang Niu Changchun Xie Jun Ying Mario Medvedovic 《Epigenetics》2018,13(3):290-300
Faroe islanders consume marine foods contaminated with methylmercury (MeHg), polychlorinated biphenyls (PCBs), and other toxicants associated with chronic disease risks. Differential DNA methylation at specific CpG sites in cord blood may serve as a surrogate biomarker of health impacts from chemical exposures. We aimed to identify key environmental chemicals in cord blood associated with DNA methylation changes in a population with elevated exposure to chemical mixtures. We studied 72 participants of a Faroese birth cohort recruited between 1986 and 1987 and followed until adulthood. The cord blood DNA methylome was profiled using Infinium HumanMethylation450 BeadChips. We determined the associations of CpG site changes with concentrations of MeHg, major PCBs, other organochlorine compounds [hexachlorobenzene (HCB), p,p’-dichlorodiphenyldichloroethylene (p,p’-DDE) and p,p’-dichlorodiphenyltrichloroethane], and perfluoroalkyl substances. In a combined sex analysis, among the 16 chemicals studied, PCB congener 105 (CB-105) exposure was associated with the majority of differentially methylated CpG sites (214 out of a total of 250). In female-only analysis, only 73 CB-105 associated CpG sites were detected, 44 of which were mapped to genes in the ELAV1-associated cancer network. In males-only, methylation changes were seen for perfluorooctane sulfonate, HCB, and p,p’-DDE in 10,598, 1,238, and 1,473 CpG sites, respectively, 15% of which were enriched in cytobands of the X-chromosome associated with neurological disorders. In this multiple-pollutant and genome-wide study, we identified key epigenetic toxicants. The significant enrichment of specific X-chromosome sites in males implies potential sex-specific epigenome responses to prenatal chemical exposures. 相似文献
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993.
免疫功能是影响动物个体适合度的重要因素之一,也是防御病原体入侵的重要途径,对动物的生存至关重要。种群密度与寄生物感染都能影响动物的免疫功能。本实验通过2×2析因实验设计,测定了母体密度应激+球虫感染、母体密度应激+未球虫感染、未母体密度应激+球虫感染、未母体密度应激+未球虫感染等4个处理对根田鼠粪便皮质酮、球虫感染率、白细胞总数、各型白细胞的百分比、淋巴细胞亚型计数(CD4,CD8计数)等指标。结果表明,高密度母体应激处理可显著降低CD4数量、CD4/CD8比例、淋巴细胞数、嗜酸性粒细胞数、白细胞数,母体应激与球虫的耦合可使上述免疫指标进一步降低,说明母体密度应激和球虫感染对于根田鼠的免疫具有负的叠加效应。 相似文献
994.
Fuyou Zhang Jianfa Li Huizhong Xiao Yifan Zou Yuchen Liu Weiren Huang 《Cell proliferation》2018,51(1)
Long non‐coding RNAs (lncRNAs), a group of non‐protein‐coding RNAs with more than 200 nucleotides in length, are involved in multiple biological processes, such as the proliferation, apoptosis, migration and invasion. Moreover, numerous studies have shown that lncRNAs play important roles as oncogenes or tumour suppressor genes in human cancers. In this paper, we concentrate on actin filament‐associated protein 1‐antisense RNA 1 (AFAP1‐AS1), a well‐known long non‐coding RNA that is overexpressed in various tumour tissues and cell lines, including oesophageal cancer, pancreatic ductal adenocarcinoma, nasopharyngeal carcinoma, lung cancer, hepatocellular carcinoma, ovarian cancer, colorectal cancer, biliary tract cancer and gastric cancer. Moreover, high expression of AFAP1‐AS1 was associated with the clinicopathological features and cancer progression. In this review, we sum up the current studies on the characteristics of AFAP1‐AS1 in the biological function and mechanism of human cancers. 相似文献
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996.
Despite increasing evidence that landscape features strongly influence the abundance and dispersal of insect populations, landscape composition has seldom been explicitly linked to genetic structure. We conducted a genetic study of the melon aphid, Aphis gossypii, in two counties of Beijing, China during spring migration using samples from watermelon. We performed aphid genetic analysis using restriction site associated DNA sequencing (2b‐RAD) and investigated the relationship between land cover and the genetic diversity. The percentage area of land cover (cropland, vegetable, orchard, grassland, woodland) was quantified in each particular scale (ranging from 0.5 km to 3 km) and was used as a predictor variable in our generalized linear models. We found a moderate level of genetic differentiation among nine sampled populations. Geographic distance and genetic distance were not significantly associated, indicating that geographic location was not a barrier to migration. These nine populations could be clustered depending on their level of genetic diversity (high and low). The genetic diversity (Shannon’s information index) was positively correlated with grassland at the spatial scales of 1 and 2 km and negatively with orchard and vegetable at 0.5 and 1 km. Genetic diversity was best predicted by the grassland + orchard + vegetable model at a spatial scale of 1 km. Based on the method of relative weights, orchard land had the greatest relative importance, followed by grassland and vegetable land, in that order. This study contributes to our understanding of the genetic variation of aphids in agricultural landscapes. 相似文献
997.
Zhihua Yi Lihui Xie Congfa Zhou Huilong Yuan Shuai Ouyang Zhi Fang Shanhong Zhao Tianyu Jia Lifang Zou Shouyu Wang Yun Xue Bing Wu Yun Gao Guilin Li Shuangmei Liu Hong Xu Changshui Xu Chunping Zhang Shangdong Liang 《Purinergic signalling》2018,14(1):47-58
The direct neurotoxicity of HIV and neurotoxicity of combination antiretroviral therapy medications both contribute to the development of neuropathic pain. Activation of satellite glial cells (SGCs) in the dorsal root ganglia (DRG) plays a crucial role in mechanical and thermal hyperalgesia. The P2Y12 receptor expressed in SGCs of the DRG is involved in pain transmission. In this study, we explored the role of the P2Y12 receptor in neuropathic pain induced by HIV envelope glycoprotein 120 (gp120) combined with ddC (2′,3′-dideoxycytidine). A rat model of gp120+ddC-induced neuropathic pain was used. Peripheral nerve exposure to HIV-gp120+ddC increased mechanical and thermal hyperalgesia in gp120+ddC-treated model rats. The gp120+ddC treatment increased expression of P2Y12 receptor mRNA and protein in DRG SGCs. In primary cultured DRG SGCs treated with gp120+ddC, the levels of [Ca2+]i activated by the P2Y12 receptor agonist 2-(Methylthio) adenosine 5′-diphosphate trisodium salt (2-MeSADP) were significantly increased. P2Y12 receptor shRNA treatment inhibited 2-MeSADP-induced [Ca2+]i in primary cultured DRG SGCs treated with gp120+ddC. Intrathecal treatment with a shRNA against P2Y12 receptor in DRG SGCs reduced the release of pro-inflammatory cytokines, decreased phosphorylation of p38 MAPK in the DRG of gp120+ddC-treated rats. Thus, downregulating the P2Y12 receptor relieved mechanical and thermal hyperalgesia in gp120+ddC-treated rats. 相似文献
998.
999.
研究了产氨短杆菌MA-2,黄色短杆菌MA-3的固定化细胞在富马酸铵转化体系中生成L-苹果酸的动力学参数,同时比较了固定化细胞在填充床及连续机械搅拌反应器中酶转化反应的差异。研究结果表明:当转化率小于40%时,酶反应在两种反应器所需的停留时间相当。随着转化率的提高,填充床反应器较连续机械搅拌反应器所需的停留时间短且不会因剪切力使固定化颗粒受到损伤,因此,在富马酸铵体系中用固定化酶生产L-苹果酸采用填 相似文献
1000.
低能量激光与集落刺激因子对人脐带血造血细胞的增殖作用 总被引:1,自引:0,他引:1
本研究用铜蒸气激光照射人脐带带血造血细胞,观察低能量激光与集落因子对造血细胞的增殖作用。结果显示激光加CSF对造血细胞GM-CFUc有协同增殖作用,与单用激光照射组,CSF刺激组及对照组相比,有非常显著性差异。 相似文献