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911.
912.
Genetic studies on attention have mainly focused on children with attention-deficit/hyperactivity disorder (ADHD), so little systematic research has been conducted on genetic correlates of attention performance and their potential brain mechanisms among healthy individuals. The current study included a genome-wide association study (GWAS, N = 1145 healthy young adults) aimed to identify genes associated with sustained attention and an imaging genetics study (an independent sample of 483 healthy young adults) to examine any identified genes' influences on brain function. The GWAS found that TTLL11 showed genome-wide significant associations with sustained attention, with rs13298112 as the most significant SNP and the GG homozygotes showing more impulsive but also more focused responses than the A allele carriers. A retrospective examination of previously published ADHD GWAS results confirmed an un-reported, small but statistically significant effect of TTLL11 on ADHD. The imaging genetics study replicated this association and showed that the TTLL11 gene was associated with resting state activity and connectivity of the somatomoter network, and can be predicted by dorsal attention network connectivity. Specifically, the GG homozygotes showed lower brain activity, weaker brain network connectivity, and non-significant brain-attention association compared to the A allele carriers. Expression database showed that expression of this gene is enriched in the brain and that the G allele is associated with lower expression level than the A allele. These results suggest that TTLL11 may play a major role in healthy individuals' attention performance and may also contribute to the etiology of ADHD.  相似文献   
913.
An efficient protocol was adopted to efficiently prepare three new series of bis(pyrazolo[1,5-a]pyrimidines) linked to different spacers. The new bis(pyrazolo[1,5-a]pyrimidines) were prepared in 80–90 % yields by reacting the respective bis(enaminones) and 4-(4-substituted benzyl)-1H-pyrazole-3,5-diamines in pyridine at reflux temperature for 5–7 h. The new products showed a wide spectrum of antibacterial activity against six different bacterial strains. In general, propane- and butane-linked bis(pyrazolo[1,5-a]pyrimidines), which are attached to 3-(4-methyl- or 4-methoxybenzyl) units, had the best antibacterial activity with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values up to 2.5 and 5.1 μM, respectively. Additionally, the previous products demonstrated promising MurB inhibitory activity with IC50 values up to 7.2 μM.  相似文献   
914.
In this study, we investigated the combined treatment of 5-fluorouracil (5-FU) and Anatolian propolis extract (PE) on colorectal cancer (CRC)using in vitro and in vivo studies. We exposed luciferase-transfected (Lovo-Luc CRC) cells and healthy colon cells (CCD-18Co) to varying concentrations of 5-FU and PE to assess their genotoxic, apoptotic, and cytotoxic effects, as well as their intracellular reactive oxygen species (iROS) levels. We also developed a xenograft model in nude mice and evaluated the anti-tumor effects of PE and 5-FU using various methods. Our findings showed that the combination of PE and 5-FU had selectivity against cancer cells, particularly at higher doses, and enhanced the anti-tumor effectiveness of 5-FU against colon CRC. The results suggest that PE can reduce side effects and increase the effectiveness of 5-FU through iROS generation in a dose-dependent manner.  相似文献   
915.
916.
In connectivity models, land cover types are assigned cost values characterizing their resistance to species movements. Landscape genetic methods infer these values from the relationship between genetic differentiation and cost distances. The spatial heterogeneity of population sizes, and consequently genetic drift, is rarely included in this inference although it influences genetic differentiation. Similarly, migration rates and population spatial distributions potentially influence this inference. Here, we assessed the reliability of cost value inference under several migration rates, population spatial patterns and degrees of population size heterogeneity. Additionally, we assessed whether considering intra-population variables, here using gravity models, improved the inference when drift is spatially heterogeneous. We simulated several gene flow intensities between populations with varying local sizes and spatial distributions. We then fit gravity models of genetic distances as a function of (i) the ‘true’ cost distances driving simulations or alternative cost distances, and (ii) intra-population variables (population sizes, patch areas). We determined the conditions making the identification of the ‘true’ costs possible and assessed the contribution of intra-population variables to this objective. Overall, the inference ranked cost scenarios reliably in terms of similarity with the ‘true’ scenario (cost distance Mantel correlations), but this ‘true’ scenario rarely provided the best model goodness of fit. Ranking inaccuracies and failures to identify the ‘true’ scenario were more pronounced when migration was very restricted (<4 dispersal events/generation), population sizes were most heterogeneous and some populations were spatially aggregated. In these situations, considering intra-population variables helps identify cost scenarios reliably, thereby improving cost value inference from genetic data.  相似文献   
917.
Existing studies suggest that biochar application can reduce soil nitrous oxide (N2O) emissions, mainly based on short-term results. However, it remains unclear what the effects (i.e., legacy effects) and underlying mechanisms are on N2O emissions after many years of a single application of biochar. Here, we collected intact soil columns from plots without and with biochar application in a subtropical tea plantation 7 years ago for an incubation experiment. We used the N2O isotopocule analysis combined with ammonia oxidizer-specific inhibitors and molecular biology approaches to investigate how the legacy effect of biochar affected soil N2O emissions. Results showed that the soil in the presence of biochar had lower N2O emissions than the control albeit statistically insignificant. The legacy effect of biochar in decreasing N2O emissions may be attributed to the reduced effectiveness of the soil substrate, nitrification and denitrification activities, and the promotion of the further reduction of N2O. The legacy effect of biochar reduced the relative contribution of nitrifier denitrification/bacterial denitrification, nitrification-related N2O production, and the relative abundance of several microorganisms involved in the nitrogen cycle. Our global meta-analysis also showed that the reduction of N2O by biochar increased with increasing application rate but diminished and possibly even reversed with increasing experimental time. In conclusion, our findings suggest that the abatement capacity of biochar on soil N2O emissions may weaken over time after biochar application, but this remains under further investigation.  相似文献   
918.
《Reproductive biology》2023,23(1):100724
Fluoride is a common environmental contaminant that has harmful effects on human health when it is present in high concentrations. Fluoride enters the bloodstream after being absorbed by the gastrointestinal system when fluoride-contaminated groundwater is consumed by people. The aim of the present study was to determine whether polyphenol-rich nano Moringa oleifera (NMO) could protect rat testicles from sodium fluoride (NaF) damage by evaluating sperm quality, sex hormones, testicular oxidative status, histopathology, and StAR gene expression. Twenty-eight adult Wistar rats were divided equally and randomly into four groups: group one received distilled water; group two received NMO at a dosage of 250 mg/kg/body weight; group three received NaF at a dosage of 10 mg/kg/body weight; and group four received NaF and NMO. The rats were orally administrated daily for a duration of eight weeks. The study's findings demonstrated that, in comparison to rats exposed to NaF alone, co-administration of NMO and NaF enhanced sperm motility and viability, decreased sperm morphological changes, restored the balance between oxidant and antioxidant status, improved testosterone and dehydroepiandrosterone, improved testicular histology, raised the Johnson score, and upregulated the StAR gene in testicular tissue. These findings show that NMO is promise as a prophylactic medication against sodium fluoride-induced testicular damage because administration of NMO had no adverse effects and enhanced reproductive health.  相似文献   
919.
摘要 目的:探索miR-150-5p靶向调控TP53基因对结直肠癌(colorectal cancer, CRC)在临床和生物学的相关性,研究miR-150-5p调控TP53基因在结直肠癌细胞增殖和侵袭病变中的作用。方法:收集临床手术切除并病理证实的结直肠癌患者的手术及血浆样本(结直肠癌和癌旁组织)60例,另选取癌旁正常粘膜10例,腺瘤30例。根据瘤体直径分为肿瘤>5 cm(n=30)和≤5 cm(n=30)。qRT-PCR法测定样本中miR-150-5p表达,荧光素酶活性测定以确定TP53是否为miR-150-5p的靶基因。使用SW480细胞株,进行Transwell小室检测细胞侵袭能力,CCK-8检测细胞增值能力,对miR-150-5p进行生物信息学分析。结果:TP53是miR-150-5p的下游基因。癌组织及血浆中miR-150-5p表达量低于癌旁组织,直径>5 cm瘤体中的miR-150-5p表达量显著低于直径≤5 cm瘤体,Ⅰ-Ⅱ期结直肠癌组织中的miR-150-5p表达显著高于Ⅲ-Ⅳ期(P<0.05)。上调miR-150-5p后,细胞中TP53表达下降,下调miR-150-5p后,TP53表达升高;CCK-8增殖试验显示细胞中miR-150-5p过表达组抑制细胞增殖(P<0.05)。结论:MiR-150-5p在结直肠癌组织和细胞中显著低表达,miR-150-5p通过靶向调节TP53抑制人CRC细胞的侵袭和增殖,有望成为结直肠癌治疗的新靶点。  相似文献   
920.
摘要 目的:探讨肝细胞癌组织中微小核糖核酸(miR)-124-3p、miR-212-5p表达与磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(Akt)信号通路和预后的关系。方法:选择2017年9月至2019年9月徐州医科大学附属医院肝胆外科收治的93例肝细胞癌患者,采用实时荧光定量聚合酶链反应(qRT-PCR)检测肝细胞癌组织中miR-124-3p、miR-212-5p、PI3K 信使RNA(mRNA)、Akt mRNA的表达。Pearson相关性分析miR-124-3p、miR-212-5p表达与PI3K/Akt信号通路相关mRNA表达的相关性。绘制Kaplan-Meier生存曲线,Log-Rank检验不同miR-124-3p、miR-212-5p表达肝细胞癌患者3年总生存率(OS)的差异。结果:肝细胞癌组织中miR-124-3p表达低于癌旁组织(P<0.05),miR-212-5p、PI3K mRNA、Akt mRNA表达高于癌旁组织(P<0.05)。肝细胞癌组织中miR-124-3p表达与PI3K mRNA、Akt mRNA表达呈负相关(P<0.05),miR-212-5p表达与PI3K mRNA、Akt mRNA表达呈正相关(P<0.05)。Ⅱa期、低分化患者肝细胞癌组织中miR-124-3p表达低于Ⅰa-Ⅰb期、中高分化患者(P<0.05),miR-212-5p表达高于Ⅰa-Ⅰb期、中高分化患者(P<0.05)。随访期间死亡37例, miR-124-3p低表达组3年OS为42.55%,低于miR-124-3p高表达组的78.26%(P<0.05),miR-212-5p高表达组3年OS为50.00%,低于miR-212-5p低表达组的71.11%(P<0.05)。结论:肝细胞癌组织中miR-124-3p表达下调,miR-212-5p表达上调,且与肝细胞癌PI3K/Akt信号通路激活,PI3K mRNA和Akt mRNA高表达,低分化,CNLC分期Ⅱa期以及低OS有关。  相似文献   
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