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961.
The tuberous root of Brassica rapa L. (turnip) is an important modified organ for nutrition storage. A better understanding of the molecular mechanisms involved in the process of tuberous root development is of great value in both economic and biological context. In this study, we analyzed the expression profiles of both mRNAs and miRNAs in tuberous roots at an early stage before cortex splitting (ES), cortex splitting stage (CSS), and secondary root thickening stage (RTS) in turnip based on high-throughput sequencing technology. A large number of differentially expressed genes (DEGs) and several differentially expressed miRNAs (DEMs) were identified. Based on the DEG analysis, we propose that metabolism is the dominant pathway in both tuberous root initiation and secondary thickening process. The plant hormone signal transduction pathway may play a predominant role in regulating tuberous root initiation, while the starch and sucrose metabolism may be more important for the secondary thickening process. These hypotheses were partially supported by sequential DEM analyses. Of all DEMs, miR156a, miR157a, and miR172a exhibited relatively high expression levels, and were differentially expressed in both tuberous root initiation and the secondary thickening process with the expression profiles negatively correlated with those of their target genes. Our results suggest that these miRNAs play important roles in tuberous root development in turnips.  相似文献   
962.
963.
Psoriasis is a chronic, inflammatory skin disease involving both environmental and genetic factors. According to genome-wide association studies (GWAS), the TNIP1 gene, which encodes the TNF-α–induced protein 3-interacting protein 1 (TNIP1), is strongly linked to the susceptibility of psoriasis. TNIP1 is a widely expressed ubiquitin sensor that binds to the ubiquitin-editing protein A20 and restricts TNF- and TLR-induced signals. In our study, TNIP1 expression decreased in specimens of epidermis affected by psoriasis. Based on previous studies suggesting a role for TNIP1 in modulating cancer cell growth, we investigated its role in keratinocyte proliferation, which is clearly abnormal in psoriasis. To mimic the downregulation or upregulation of TNIP1 in HaCaT cells and primary human keratinocytes (PHKs), we used a TNIP1 specific small interfering hairpin RNA (TNIP1 shRNA) lentiviral vector or a recombinant TNIP1 (rTNIP1) lentiviral vector, respectively. Blocking TNIP1 expression increased keratinocyte proliferation, while overexpression of TNIP1 decreased keratinocyte proliferation. Furthermore, we showed that TNIP1 signaling might involve extracellular signal-regulated kinase1/2 (Erk1/2) and CCAAT/enhancer-binding protein β (C/EBPβ) activity. Intradermal injection of TNIP1 shRNA in BALB/c mice led to exaggerated psoriatic conditions in imiquimod (IMQ)-induced psoriasis-like dermatitis. These findings indicate that TNIP1 has a protective role in psoriasis and therefore could be a promising therapeutic target.  相似文献   
964.
BMP15 (Bone morphogenetic protein 15) is an oocyte-secreted growth factor required for ovarian follicle development and ovulation in mammals, but its effects on reproduction in chickens are unclear. In this study, the association between BMP15 polymorphisms and reproduction traits were analyzed, and its expression characteristics in different tissues were explored in LaiWu Black chickens. Three single nucleotide polymorphisms (SNPs) were identified in four hundred LaiWu Black chickens. One SNP (NC_006091.3:g.1773T>C) located in exon 2 which was significantly associated with egg weight at first egg (EWFE) (P = 0.0389), was novel. Diplotypes based on the three SNPs were found to be significantly associated with egg weight at age of 43W (EW43) (P = 0.0058). The chickens with H3H3 diplotype had their first egg 0.57 days later than chickens with H5H5 diplotype and 1.21 days-3.96 days earlier than the other five diplotype chickens. The egg production at age of 43W (E43), egg production at age of 46W (E46) and egg production at age of 48W (E48) for chickens with H3H3 diplotype were the highest among all the chickens, and the E48 of chickens with H3H3 diplotype had 11.83 eggs higher than chickens with H1H5 diplotype. RT-qPCR results showed that the expression level of BMP15 gene in ovarian follicle was in the order of 4 mm>6 mm -8 mm> 15 mm -19 mm> 23 mm -29 mm > 33 mm -34 mm in diameter. The mRNA level in follicles of 4 mm and 6–8 mm in diameter were significantly higher than that in the other follicles (P<0.01). In the same week, the highest mRNA level was found in the ovary, and it was significantly different from that found in the liver and oviduct (P<0.01). Our results indicate that BMP15 plays a vital role in the development of ovary and follicles, especially in the development of primary follicles. H3H3 may be an potential advantageous molecular marker for improving reproduction traits in chickens.  相似文献   
965.
Human rights advocates play a critical role in promoting respect for human rights world-wide, and engage in a broad range of strategies, including documentation of rights violations, monitoring, press work and report-writing, advocacy, and litigation. However, little is known about the impact of human rights work on the mental health of human rights advocates. This study examined the mental health profile of human rights advocates and risk factors associated with their psychological functioning. 346 individuals currently or previously working in the field of human rights completed an internet-based survey regarding trauma exposure, depression, posttraumatic stress disorder (PTSD), resilience and occupational burnout. PTSD was measured with the Posttraumatic Stress Disorder Checklist-Civilian Version (PCL-C) and depression was measured with the Patient History Questionnaire-9 (PHQ-9). These findings revealed that among human rights advocates that completed the survey, 19.4% met criteria for PTSD, 18.8% met criteria for subthreshold PTSD, and 14.7% met criteria for depression. Multiple linear regressions revealed that after controlling for symptoms of depression, PTSD symptom severity was predicted by human rights-related trauma exposure, perfectionism and negative self-appraisals about human rights work. In addition, after controlling for symptoms of PTSD, depressive symptoms were predicted by perfectionism and lower levels of self-efficacy. Survey responses also suggested high levels of resilience: 43% of responders reported minimal symptoms of PTSD. Although survey responses suggest that many human rights workers are resilient, they also suggest that human rights work is associated with elevated rates of PTSD and depression. The field of human rights would benefit from further empirical research, as well as additional education and training programs in the workplace about enhancing resilience in the context of human rights work.  相似文献   
966.
BackgroundGlucose homeostasis is a trait of healthy ageing and is crucial to the elderly, but less consideration has been given to the age composition in most studies involving genetics and hyperglycemia.MethodsSeven variants in FOXO3 were genotyped in three cohorts (n = 2037; LLI, MI_S and MI_N; mean age: 92.5±3.6, 45.9±8.2 and 46.8±10.3, respectively) to compare the contribution of FOXO3 to fasting hyperglycemia (FH) between long-lived individuals (LLI, aged over 90 years) and middle-aged subjects (aged from 35–65 years).ResultsA different genetic predisposition of FOXO3 alleles to FH was observed between LLI and both of two middle-aged cohorts. In the LLI cohort, the longevity beneficial alleles of three variants with the haplotype “AGGC” in block 1 were significantly protective to FH, fasting glucose, hemoglobin A1C and HOMA-IR. Notably, combining multifactor dimensionality reduction and logistic regression, we identified a significant 3-factor interaction model (rs2802288, rs2802292 and moderate physical activity) associated with lower FH risk. However, not all of the findings were replicated in the two middle-aged cohorts.ConclusionOur data provides a novel insight into the inconsistent genetic determinants between middle-aged and LLI subjects. FOXO3 might act as a shared genetic predisposition to hyperglycemia and lifespan.  相似文献   
967.
The combination of surfactant enhanced soil washing and degradation of nitrobenzene (NB) in effluent with persulfate was investigated to remediate NB contaminated soil. Aqueous solution of sodium dodecylbenzenesulfonate (SDBS, 24.0 mmol L-1) was used at a given mass ratio of solution to soil (20:1) to extract NB contaminated soil (47.3 mg kg-1), resulting in NB desorption removal efficient of 76.8%. The washing effluent was treated in Fe2+/persulfate and Fe2+/H2O2 systems successively. The degradation removal of NB was 97.9%, being much higher than that of SDBS (51.6%) with addition of 40.0 mmol L-1 Fe2+ and 40.0 mmol L-1 persulfate after 15 min reaction. The preferential degradation was related to the lone pair electron of generated SO4, which preferably removes electrons from aromatic parts of NB over long alkyl chains of SDBS through hydrogen abstraction reactions. No preferential degradation was observed in •OH based oxidation because of its hydrogen abstraction or addition mechanism. The sustained SDBS could be reused for washing the contaminated soil. The combination of the effective surfactant-enhanced washing and the preferential degradation of NB with Fe2+/persulfate provide a useful option to remediate NB contaminated soil.  相似文献   
968.
Small heat shock proteins (sHSPs) can regulate protein folding and protect cells from stress. To investigate the role of sHSPs in the silk-producing insect Antheraea pernyi response to microorganisms, a sHsp gene termed as Ap-sHSP21.4, was identified. This gene encoded a 21.4 kDa protein which shares the conserved structure of insect sHsps and belongs to sHSP21.4 family. Ap-sHSP21.4 was highly expressed in fat body and up-regulated in midgut and fat body of A. pernyi challenged with Escherichia coli, Beauveria bassiana and nuclear polyhedrosis virus (NPV), which was determined by quantitative real-time PCR. Meanwhile, knock down of Ap-sHSP21.4 with dsRNA result in the decrease at the expression levels of several immune response-related genes (defensin, Dopa decarboxylase, Toll1, lysozyme and Kazal-type serine protease inhibitor). Additionally, the impact of eicosanoid biosynthesis on the expression of Ap-sHSP21.4 response to NPV was determined using qPCR, inhibitors of eicosanoid biosynthesis significantly suppress Ap-HSP21.4 expression upon NPV challenge. All together, Ap-sHSP21.4 was involved in the immunity of A. pernyi against microorganism and possibly mediated by eicosanoids pathway. These results will shed light in the understanding of the pathogen-host interaction in A. pernyi.  相似文献   
969.
The growing interest in studying social behaviours of swarming fruit flies, Drosophila melanogaster, has heightened the need for developing tools that provide quantitative motion data. To achieve such a goal, multi-camera three-dimensional tracking technology is the key experimental gateway. We have developed a novel tracking system for tracking hundreds of fruit flies flying in a confined cubic flight arena. In addition to the proposed tracking algorithm, this work offers additional contributions in three aspects: body detection, orientation estimation, and data validation. To demonstrate the opportunities that the proposed system offers for generating high-throughput quantitative motion data, we conducted experiments on five experimental configurations. We also performed quantitative analysis on the kinematics and the spatial structure and the motion patterns of fruit fly swarms. We found that there exists an asymptotic distance between fruit flies in swarms as the population density increases. Further, we discovered the evidence for repulsive response when the distance between fruit flies approached the asymptotic distance. Overall, the proposed tracking system presents a powerful method for studying flight behaviours of fruit flies in a three-dimensional environment.  相似文献   
970.
Atrophy of the cortical thickness and gray matter volume are regarded as sensitive markers for the early clinical diagnosis of Alzheimer’s disease (AD). This study aimed to investigate differences in atrophy patterns in the frontal-subcortical circuits between MCI and AD, assess whether these differences were essential for the pathologic basis of cognitive impairment. A total of 131 individuals were recruited, including 45 with cognitively normal controls (CN), 46 with MCI, and 40 with AD. FreeSurfer software was used to perform volumetric measurements of the frontal-subcortical circuits from 3.0T magnetic resonance (MR) scans. Data revealed that both MCI and AD subjects had a thinner cortex in the left caudal middle frontal gyrus and the left lateral orbitofrontal gyrus compared with CN individuals. The left lateral orbitofrontal gyrus was also thinner in AD compared with MCI patients. There were no statistically significant differences in the cortical mean curvature among the three groups. Both MCI and AD subjects exhibited smaller bilateral hippocampus volumes compared with CN individuals. The volumes of the bilateral hippocampus and the right putamen were also smaller in AD compared with MCI patients. Logistic regression analyses revealed that the left lateral orbitofrontal gyrus and bilateral hippocampus were risk factors for cognitive impairment. These current results suggest that atrophy was heterogeneous in subregions of the frontal-subcortical circuits in MCI and AD patients. Among these subregions, the reduced thickness of the left lateral orbitofrontal and the smaller volume of the bilateral hippocampus seemed to be markers for predicting cognitive impairment.  相似文献   
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