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排序方式: 共有1295条查询结果,搜索用时 31 毫秒
991.
Zhang L  Yan J  Xu Y  Long L  Zhu C  Chen X  Jiang Y  Yang L  Bian L  Wang Q 《PloS one》2011,6(4):e19333

Background

The elevation of plasma homocysteine (Hcy) and C-reactive protein (CRP) has been correlated to an increased risk of Parkinson''s disease (PD) or vascular diseases. The association and clinical relevance of a combined assessment of Hcy and CRP levels in patients with PD and vascular parkinsonism (VP) are unknown.

Methodology/Principal Findings

We performed a cross-sectional study of 88 Chinese patients with PD and VP using a clinical interview and the measurement of plasma Hcy and CRP to determine if Hcy and CRP levels in patients may predict the outcomes of the motor status, non-motor symptoms (NMS), disease severity, and cognitive declines. Each patient''s NMS, cognitive deficit, disease severity, and motor status were assessed by the Nonmotor Symptoms Scale (NMSS), Mini-Mental State Examination (MMSE), the modified Hoehn and Yahr staging scale (H&Y), and the unified Parkinson''s disease rating scale part III (UPDRS III), respectively. We found that 100% of patients with PD and VP presented with NMS. The UPDRS III significantly correlated with CRP (P = 0.011) and NMSS (P = 0.042) in PD patients. The H&Y was also correlated with Hcy (P = 0.002), CRP (P = 0.000), and NMSS (P = 0.023) in PD patients. In VP patients, the UPDRS III and H&Y were not significantly associated with NMSS, Hcy, CRP, or MMSE. Strong correlations were observed between Hcy and NMSS as well as between CRP and NMSS in PD and VP.

Conclusions/Significance

Our findings support the hypothesis that Hcy and CRP play important roles in the pathogenesis of PD. The combination of Hcy and CRP may be used to assess the progression of PD and VP. Whether or not anti-inflammatory medication could be used in the management of PD and VP will produce an interesting topic for further research.  相似文献   
992.
Li Q  Bian S  Hong J  Kawase-Koga Y  Zhu E  Zheng Y  Yang L  Sun T 《PloS one》2011,6(10):e26000
The adult hippocampus consists of the dentate gyrus (DG) and the CA1, CA2 and CA3 regions and is essential for learning and memory functions. During embryonic development, hippocampal neurons are derived from hippocampal neuroepithelial cells and dentate granular progenitors. The molecular mechanisms that control hippocampal progenitor proliferation and differentiation are not well understood. Here we show that noncoding microRNAs (miRNAs) are essential for early hippocampal development in mice. Conditionally ablating the RNAase III enzyme Dicer at different embryonic time points utilizing three Cre mouse lines causes abnormal hippocampal morphology and affects the number of hippocampal progenitors due to altered proliferation and increased apoptosis. Lack of miRNAs at earlier stages causes early differentiation of hippocampal neurons, in particular in the CA1 and DG regions. Lack of miRNAs at a later stage specifically affects neuronal production in the CA3 region. Our results reveal a timing requirement of miRNAs for the formation of specific hippocampal regions, with the CA1 and DG developmentally hindered by an early loss of miRNAs and the CA3 region to a late loss of miRNAs. Collectively, our studies indicate the importance of the Dicer-mediated miRNA pathway in hippocampal development and functions.  相似文献   
993.
Lu R  Zhang X  Huang D  Huang B  Gao N  Wang Z  Ge J 《PloS one》2011,6(11):e25713
Severe ocular surface diseases are some of the most challenging problems that the clinician faces today. Conventional management is generally unsatisfactory, and the long-term ocular consequences of these conditions are devastating. It is significantly important to find a substitute for conjunctival epithelial cells. This study was to explore the possibility of progenitor cell-derived epidermal sheets on denuded amniotic membrane to reconstruct ocular surface of conjunctiva damaged monkeys. We isolated epidermal progenitor cells of rhesus monkeys by type IV collagen adhesion, and then expanded progenitor cell-derived epidermal sheets on denuded amniotic membrane ex vivo. At 3 weeks after the conjunctiva injury, the damaged ocular surface of four monkeys was surgically reconstructed by transplanting the autologous cultivated epidermal progenitor cells. At 2 weeks after surgery, transplants were removed and examined with Hematoxylin-eosin staining, Periodic acid Schiff staining, immunofluorescent staining, scanning and transmission electron microscopy. Histological examination of transplanted sheets revealed that the cell sheets were healthy alive, adhered well to the denuded amniotic membrane, and had several layers of epithelial cells. Electron microscopy showed that the epithelial cells were very similar in appearance to those of normal conjunctival epithelium, even without goblet cell detected. Epithelial cells of transplants had numerous desmosomal junctions and were attached to the amniotic membrane with hemidesmosomes. Immunohistochemistry confirmed the presence of the conjunctival specific markers, mucin 4 and keratin 4, in the transplanted epidermal progenitor cells. In conclusion, our present study successfully reconstructed conjunctiva with autologous transplantation of progenitor cell-derived epidermal sheets on denuded AM in conjunctival damaged monkeys, which is the first step toward assessing the use of autologous transplantation of progenitor cells of nonocular surface origin. Epidermal progenitor cells could be provided as a new substitute for conjunctival epithelial cells to overcome the problems of autologous conjunctiva shortage.  相似文献   
994.

Background

The large conductance calcium-activated potassium channel alpha-subunit (Slo) is widely distributed throughout the body and plays an important role in a number of diseases. Prior work has shown that Slo, through its S10 region, interacts with β-catenin, a key component of the cytoskeleton framework and the Wnt signaling pathway. However, the physiological significance of this interaction was not clear.

Methodology/Principal Findings

Using a combination of proteomic and cell biology tools we show the existence of additional multiple binding sites in Slo, and explore in detail β-catenin interactions with the S10 region. We demonstrate that deletion of this region reduces Slo surface expression in HEK cells, which indicates that interaction with beta-catenin is important for Slo surface expression. This is confirmed by reduced expression of Slo in HEK cells and chicken (Gallus gallus domesticus leghorn white) hair cells treated with siRNA to β-catenin. HSlo reciprocally co-immunoprecipitates with β-catenin, indicating a stable binding between these two proteins, with the S10 deletion mutant having reduced binding with β-catenin. We also observed that mutations of the two putative GSK phosphorylation sites within the S10 region affect both the surface expression of Slo and the channel''s voltage and calcium sensitivities. Interestingly, expression of exogenous Slo in HEK cells inhibits β-catenin-dependent canonical Wnt signaling.

Conclusions and Significance

These studies identify for the first time a central role for β-catenin in mediating Slo surface expression. Additionally we show that Slo overexpression can lead to downregulation of Wnt signaling.  相似文献   
995.
When attacked by herbivores, plants emit volatiles to attract parasitoids and predators of herbivores. However, our understanding of the effect of plant volatiles on the subsequent behaviour of conspecific parasitoids when herbivores on plants are parasitized is limited. In this study, rice plants were infested with gravid females of the brown planthopper (BPH) Nilaparvata lugens for 24 hr followed by another 24 hr in which the BPH eggs on plants were permitted to be parasitized by their egg parasitoid, Anagrus nilaparvatae; volatiles from rice plants that underwent such treatment were less attractive to subsequent conspecific parasitoids compared to the volatiles from plants infested with gravid BPH females alone. Chemical analysis revealed that levels of JA and JA-Ile as well as of four volatile compounds—linalool, MeSA, α-zingiberene and an unknown compound—from plants infested with BPH and parasitized by wasps were significantly higher than levels of these compounds from BPH-infested plants. Laboratory and field bioassays revealed that one of the four increased chemicals—α-zingiberene—reduced the plant's attractiveness to the parasitoid. These results suggest that host plants can fine-tune their volatiles to help egg parasitoids distinguish host habitats with parasitized hosts from those without.  相似文献   
996.
肠道微生物对于人体健康的重要作用已经得到广泛证实,目前,对肠道微生物的研究大多采用基于扩增细菌16S rRNA基因V3-V4区的高通量测序分析,对古菌的关注较少。本研究选择了一对可以同时扩增细菌和古菌16S rRNA基因的引物,通过比较人为干扰肠道微生物前后的群落变化,说明这对引物适宜分析人类肠道细菌和古菌群落变化并具有一定优越性。采集志愿者粪便样品,同时用仅能扩增细菌引物 (B引物) 和细菌古菌通用引物 (AB引物) 进行扩增和高通量测序;使用几个常用的rRNA数据库判断引物对细菌的覆盖度和对古菌的扩增能力。结果表明,AB引物在可以展示B引物扩增出的细菌群落的基础上,可以得到肠道中常见的产甲烷古菌的序列,同时也展示出人为干扰肠道微生物前后的群落结构变化。AB引物可以仅通过一次扩增和测序同时分析肠道中的细菌和古菌群落,更加全面展示肠道微生物群落结构,适用于肠道微生物相关研究。  相似文献   
997.
Achilles tendon healing (ATH) remains an unanswered question in the field of sports medicine because it does not produce tissue with homology to the previously uninjured tissue. Oestrogen receptor β (ERβ) is involved in the injury and repair processes of tendons. Our previous study confirmed that ERβ plays a role in the early stage of ATH by affecting adipogenesis, but its role in extracellular matrix (ECM) remodelling is unknown. We established a 4‐week Achilles tendon repair model to investigate the mechanism through which ERβ affects ATH at the very beginning of ECM remodelling phase. In vitro studies were performed using tendon‐derived stem cells (TDSCs) due to their promising role in tendon healing. Behavioural and biomechanical tests revealed that ERβ‐deficient mice exhibit weaker mobility and inferior biomechanical properties, and immunofluorescence staining and qRT‐PCR showed that these mice exhibited an erroneous ECM composition, as mainly characterized by decreased collagen type I (Col I) deposition. The changes in gene expression profiles between ERβ‐knockout and WT mice at 1 week were analysed by RNA sequencing to identify factors affecting Col I deposition. The results highlighted the IRF5‐CCL3 axis, and this finding was verified with CCL3‐treated TDSCs. These findings revealed that ERβ regulates Col I deposition during ATH via the IRF5‐CCL3 axis.  相似文献   
998.
999.
The greenfin horse‐faced filefish, Thamnaconus septentrionalis, is a valuable commercial fish species that is widely distributed in the Indo‐West Pacific Ocean. This fish has characteristic blue–green fins, rough skin and a spine‐like first dorsal fin. Thamnaconus septentrionalis is of conservation concern because its population has declined sharply, and it is an important marine aquaculture fish species in China. Genomic resources for the filefish are lacking, and no reference genome has been released. In this study, the first chromosome‐level genome of T. septentrionalis was constructed using nanopore sequencing and Hi‐C technology. A total of 50.95 Gb polished nanopore sequences were generated and were assembled into a 474.31‐Mb genome, accounting for 96.45% of the estimated genome size of this filefish. The assembled genome contained only 242 contigs, and the achieved contig N50 was 22.46 Mb, a surprisingly high value among all sequenced fish species. Hi‐C scaffolding of the genome resulted in 20 pseudochromosomes containing 99.44% of the total assembled sequences. The genome contained 67.35 Mb of repeat sequences, accounting for 14.2% of the assembly. A total of 22,067 protein‐coding genes were predicted, 94.82% of which were successfully annotated with putative functions. Furthermore, a phylogenetic tree was constructed using 1,872 single‐copy orthologous genes, and 67 unique gene families were identified in the filefish genome. This high‐quality assembled genome will be a valuable resource for a range of future genomic, conservation and breeding studies of T. septentrionalis.  相似文献   
1000.
目的分析儿童重型再生障碍性贫血(SAA)单倍体造血干细胞移植和同胞全相合移植并发症发生率。方法回顾性分析2010年1月1日至2018年12月31日于苏州大学附属儿童医院进行治疗的SAA患儿(56例),分为治疗组(单倍体造血干细胞移植,35例),对照组(同胞全相合移植,21例)。其中患儿年龄、诊断距离移植时间、总单个核细胞数、总CD34+细胞数、中位随访时间、粒细胞植入时间、血小板植入时间及等级资料[供受体血型相合程度、急性移植物抗宿主病(aGVHD)分级、广泛性慢性移植物抗宿主病(cGVHD)分级、出血性膀胱炎分级、渗漏综合征分级]采用Mann-Whitney U检验。性别、疾病种类、供体与受体性别、预处理方案、CD20单抗的使用、HLA配型、供体来源、移植物来源、植入综合征、巨细胞病毒(CMV)血症、EB病毒(EBV)血症、死亡人数、植入失败人数和骨髓增殖不良人数使用卡方检验进行组间分析。生存曲线以及累积发生率用Kaplan-Meier法绘制,并使用Log-rank检验分析组间差异。结果与对照组比较,治疗组CD19+B细胞的重建延迟,而CD16+CD56+NK细胞数量移植后6个月开始增加,逐渐达到对照组的水平。与对照组比较,治疗组aGVHD、cGVHD、植入综合征和骨髓增殖不良累积发生率(14.29﹪±7.64﹪比57.14﹪±8.36﹪,11.67﹪±7.75﹪比61.59﹪±9.65﹪,9.53﹪±6.41﹪比74.86﹪±7.43﹪,0.0﹪比14.29﹪±5.91﹪)均升高,差异具有统计学意义(P<0.05),两组CMV与EBV感染,5年总体生存率(OS)、无失败生存率(FFS)、无GVHD失败存活率(GFFS)、Ⅲ-Ⅳ度aGVHD及广泛性cGVHD累积发生率比较差异无统计意义(P>0.05)。结论单倍体移植是治疗儿童SAA的有效治疗方案,但与同胞全合造血干细胞移植比较,其GVHD发生率较高,植入综合征和骨髓增殖不良的发生率较高,优化单倍体移植方案有望降低并发症,提高儿童重型再生障碍性贫血的生活质量。  相似文献   
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