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941.
942.
Notch receptors are key regulators of nervous system development and promoters of neural stem cells renewal and proliferation. Defects in the expression of Notch genes result in severe, often lethal developmental abnormalities. Notch3 is generally thought to have a similar proliferative, anti‐differentiation and gliogenic role to Notch1. However, in some cases, Notch3 has an opposite, pro‐differentiation effect. Here, we show that Notch3 segregates from Notch1 and is transiently expressed in adult rat and mouse spinal cord neuron precursors and immature neurons. This suggests that during the differentiation of adult neural progenitor cells, Notch signalling may follow a modified version of the classical lateral inhibition model, involving the segregation of individual Notch receptors. Notch3 knockout mice, otherwise neurologically normal, are characterized by a reduced number of mature inhibitory interneurons and an increased number of highly excitable immature neurons in spinal cord laminae I–II. As a result, these mice have permanently lower nociceptive thresholds, similar to chronic pain. These results suggest that defective neuronal differentiation, for example as a result of reduced Notch3 expression or activation, may underlie human cases of intractable chronic pain, such as fibromyalgia and neuropathic pain. 相似文献
943.
目的:探讨老年高血压合并2 型糖尿病患者血清同型半胱氨酸(Homocysteine, Hcy)、血尿酸(Serum uric acid, SUA)水平变
化及其临床意义。方法:2012 年9 月至2013 年9 月期间,我院诊治的40 例单纯高血压和40 例高血压合并2 型糖尿病患者,分别
作为对照组和研究组,检测两组血清Hcy、SUA水平。结果:两组患者收缩压、舒张压比较无统计学差异(P>0.05)。研究组空腹血
糖、餐后2h 血糖、血清Hcy、SUA 均显著高于对照组(P<0.05)。研究组中血管并发症患者血清Hcy、SUA为(25.0± 5.0)umol/L 和
(390.0± 65.0)mmol/L显著高于无血管并发症患者(17.0± 4.0)umol/L 和(330.0± 55.0)mmol/L,血管并发症患者FBG、餐后2h 血
糖与无血管并发症患者比较无统计学差异(P>0.05)。结论:高血压合并2 型糖尿病患者血清Hcy、SUA异常升高,且存在慢性血
管并发症患者两者水平更高,血清Hcy、SUA是老年高血压合并2 型糖尿病的危险因素。 相似文献
944.
Jia-zeng?Sun Jigui?Wang Shuang?Wang Daoli?Yuan Zhili?Li Bao?Yi Qiang?Hou Yaping?Mao Weiquan?LiuEmail author 《Virology journal》2014,11(1):210
Mink enteritis virus (MEV) is one of the most important pathogens in the mink industry. Recent studies have shed light into the role of microRNAs (miRNAs), small noncoding RNAs of length ranging from 18–23 nucleotides (nt), as critical modulators in the host-pathogen interaction networks. We previously showed that miRNA miR-181b can inhibit MEV replication by repression of viral non-structural protein 1 expression. Here, we report that two other miRNAs (miR-320a and miR-140) inhibit MEV entry into feline kidney (F81) cells by downregulating its receptor, transferrin receptor (TfR), by targeting the 3′ untranslated region (UTR) of TfR mRNA, while being themselves upregulated. 相似文献
945.
Yin Li Xiang Mao Qiong Wang Jinrui Zhang Xiaoyan Li Fengyun Ma Fusheng Sun Junli Chang Mingjie Chen Yuesheng Wang Kexiu Li Guangxiao Yang Guangyuan He 《Molecular breeding : new strategies in plant improvement》2014,33(3):545-554
Durum wheat is the second-most widely grown wheat species, and is primarily used in the production of pasta and couscous. The grain utilization of durum wheat is partly related to its very hard kernel texture because of the lack of the D genome and consequentially the Puroindoline genes. Our previous study reported the transformation of durum wheat with the Puroindoline a (Pina) gene. Here, we characterized the transgenic durum wheat lines expressing the Pina gene, and studied the effects of PINA on grain texture and other kernel characteristics. SDS-PAGE and Western blotting results demonstrated that starch-bound PINA levels of Pina-overexpressing lines were lower than that of Pina-positive control, common wheat cv. Chinese Spring, suggesting a weak association of PINA protein with starch granules in the absence of Pinb. Grain hardness analysis and flour milling tests indicated that the overexpression of PINA resulted in decreased grain hardness and increased flour yield in transgenic durum wheat lines. The agronomic performance of the transgenic and control lines was also examined and it was found that no significant differences in measured traits were observed between Pina-overexpressing and control lines in the 2-year field trials. Since grain hardness strongly affects milling and end-use qualities, the development of medium–hard-textured durum wheat lines is not only of significance for our knowledge of grain hardness and Puroindolines, but also has practical implications for plant breeders and food technologists for the expansion of utilization of durum wheat. 相似文献
946.
Junzhi Zhou Beibei Mao Qi Zhou Deqiang Ding Miao Wang Peng Guo Yuhao Gao Jerry W. Shay Zengqiang Yuan Yu‐Sheng Cong 《Aging cell》2014,13(1):197-200
Telomerase contributes to cell proliferation and survival through both telomere‐dependent and telomere‐independent mechanisms. In this report, we discovered that endoplasmic reticulum (ER) stress transiently activates the catalytic components of telomerase (TERT) expression in human cancer cell lines and murine primary neural cells. Importantly, we show that depletion of hTERT sensitizes cells to undergo apoptosis under ER stress, whereas increased hTERT expression reduces ER stress‐induced cell death independent of catalytically active enzyme or DNA damage signaling. Our findings establish a functional link between ER stress and telomerase, both of which have important implications in the pathologies associated with aging and cancer. 相似文献
947.
Dan Yang Qiong Zhao Rong Mao Lu-Jun Li De-Hui Zeng 《Soil & Sediment Contamination》2014,23(5):497-503
The deposition of Mg-rich dust from magnesite calcination can lead to serious soil contamination. As an efficient remediation method, phytoremediation is often used to remove contaminants from the environment. However, no information is available on phytoremediation of Mg-contaminated soils. In this study, we determined the Mg concentrations in above- and belowground parts of six dominant plant species and soils (0–20 cm layer) beneath these plants in a magnesite mining region in Northeast China. Mg was enriched in leaves of all six species. Translocation factors (TF) of all six species were far greater than 1. Enrichment factors (EF) of Kochia scoparia, Cassia nomame, and Hordeum jubatum were 1.1, 1.1, and 1.0, respectively, while those of the other three species were not greater than 0.5. The results suggest that Kochia scoparia, Cassia nomame, and Hordeum jubatum are the potential Mg-accumulators, and could be used for remediation of Mg-contaminated soils. 相似文献
948.
Limei Ouyang Jeeyun Lee Cheol-Keun Park Mao Mao Yujian Shi Zhuolin Gong Hancheng Zheng Yingrui Li Yonggang Zhao Guangbiao Wang Huiling Fu Jhingook Kim Ho Yeong Lim 《BMC medical genomics》2014,7(1):1-13
Background
To gain biological insights into lung metastases from hepatocellular carcinoma (HCC), we compared the whole-genome sequencing profiles of primary HCC and paired lung metastases.Methods
We used whole-genome sequencing at 33X-43X coverage to profile somatic mutations in primary HCC (HBV+) and metachronous lung metastases (> 2 years interval).Results
In total, 5,027-13,961 and 5,275-12,624 somatic single-nucleotide variants (SNVs) were detected in primary HCC and lung metastases, respectively. Generally, 38.88-78.49% of SNVs detected in metastases were present in primary tumors. We identified 65–221 structural variations (SVs) in primary tumors and 60–232 SVs in metastases. Comparison of these SVs shows very similar and largely overlapped mutated segments between primary and metastatic tumors. Copy number alterations between primary and metastatic pairs were also found to be closely related. Together, these preservations in genomic profiles from liver primary tumors to metachronous lung metastases indicate that the genomic features during tumorigenesis may be retained during metastasis.Conclusions
We found very similar genomic alterations between primary and metastatic tumors, with a few mutations found specifically in lung metastases, which may explain the clinical observation that both primary and metastatic tumors are usually sensitive or resistant to the same systemic treatments. 相似文献949.
Dongdong Di Buyun Cui Heng Wang Hongyan Zhao Dongri Piao Lili Tian Guozhong Tian Jingli Kang Xiang Mao Xiaojun Zhang Pengfei Du Lin Zhu Zhuo Zhao Lingling Mao Wenqing Yao Pingyuan Guan Weixing Fan Hai Jiang 《PloS one》2014,9(1)
In China, brucellosis is an endemic disease typically caused by Brucella melitensis infection (biovars 1 and 3). Brucella canis infection in dogs has not traditionally recognized as a major problem. In recent years however, brucellosis resulting from Brucella canis infection has also been reported, suggesting that infections from this species may be increasing. Data concerning the epidemiology of brucellosis resulting from Brucella canis infection is limited. Therefore, the purpose of this study was to assess the diversity among Chinese Brucella canis strains for epidemiological purposes. First, we employed a 16-marker VNTR assay (Brucella MLVA-16) to assess the diversity and epidemiological relationship of 29 Brucella canis isolates from diverse locations throughout China with 38 isolates from other countries. MLVA-16 analysis separated the 67 Brucella canis isolates into 57 genotypes that grouped into five clusters with genetic similarity coefficients ranging from 67.73 to 100%. Moreover, this analysis revealed a new genotype (2-3-9-11-3-1-5-1:118), which was present in two isolates recovered from Guangxi in 1986 and 1987. Second, multiplex PCR and sequencing analysis were used to determine whether the 29 Chinese Brucella canis isolates had the characteristic BMEI1435 gene deletion. Only two isolates had this deletion. Third, amplification of the omp25 gene revealed that 26 isolates from China had a T545C mutation. Collectively, this study reveals that considerable diversity exists among Brucella canis isolates in China and provides resources for studying the genetic variation and microevolution of Brucella. 相似文献
950.
Yu Sun Hongxia Zhang Ruimin Hu Jianyong Sun Xing Mao Zhonghua Zhao Qi Chen Zhigang Zhang 《PloS one》2014,9(4)
Growing evidence suggests that there are many common cell biological features shared by neurons and podocytes; however, the mechanism of podocyte foot process formation remains unclear. Comparing the mechanisms of process formation between two cell types should provide useful guidance from the progress of neuron research. Studies have shown that some mature proteins of podocytes, such as podocin, nephrin, and synaptopodin, were also expressed in neurons. In this study, using cell biological experiments and immunohistochemical techniques, we showed that some neuronal iconic molecules, such as Neuron-specific enolase, nestin and Neuron-specific nuclear protein, were also expressed in podocytes. We further inhibited the expression of Neuron-specific enolase, nestin, synaptopodin and Ubiquitin carboxy terminal hydrolase-1 by Small interfering RNA in cultured mouse podocytes and observed the significant morphological changes in treated podocytes. When podocytes were treated with Adriamycin, the protein expression of Neuron-specific enolase, nestin, synaptopodin and Ubiquitin carboxy terminal hydrolase-1 decreased over time. Meanwhile, the morphological changes in the podocytes were consistent with results of the Small interfering RNA treatment of these proteins. The data demonstrated that neuronal iconic proteins play important roles in maintaining and regulating the formation and function of podocyte processes. 相似文献