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81.
Qiupeng Zheng Jing Du Zhaofeng Zhang Jianhua Xu Lingyuan Fu Yunlei Cao Xianliang Huang Lingli Guo 《Gene》2013
Vascular malformations (VMs) are common congenital and neonatal dysmorphogenesis. VMs mostly occur sporadically with a few exceptions of inheritability. Tie2/angiopoietins-2 (Ang-2) and VEGF/KDR pathways are known to be involved in normal and pathogenic angiogenesis. Our study was aimed to test the contribution of these pathway gene variants to VMs. A total of 8 variants were found among 103 VM patients and 142 healthy controls. These variants comprised rs638203, rs639225, rs80338908 and rs80338909 in Tie2 gene, rs1870377 and rs2305949 in KDR gene, rs79337921 and rs34590960 in ANTXR1 gene. Our results indicated that rs638203 (p = 0.029) and rs639225 (p = 0.018) in Tie2 gene were associated with VM. A further bioinformatics analysis suggested the rs638203-G and rs639225-G might cause an abnormal splicing of Tie2 gene into to a defective protein. Our results identified two novel Tie2 gene polymorphisms with genetic susceptibility to VMs, although future functional validation of the two polymorphisms is warranted in the future. 相似文献
82.
83.
Xiao Fu Guanghui Cui Shuaishuai Liu Song Zhao 《Journal of cellular and molecular medicine》2020,24(2):1670-1675
This study aimed to explore the underlying mechanism of linc01014 in oesophagus cancer gefitinib resistance. Gefitinib‐resistant oesophagus squamous cell carcinoma (ESCC gefitinibR) cell lines were constructed by using different gefitinib treatment in FLO‐1, KYAE‐1, TE‐8 and TE‐5 cell lines and confirmed by MTS50 and proliferation assays. Expression of linc01014 was overexpressed/silenced in FLO‐1 cells followed by gefitinib treatment, and then, the apoptosis‐associated markers Bax and Bcl‐2, and PI3KCA in PI3K signalling pathway were determined using Western blotting. MST50 and morphology analyses showed that ESCC gefitinibR cell lines presented obvious gefitinib resistance than their parental ESCC cell lines. ESCC gefitinibR cell lines showed significantly higher proliferation abilities than their parental ESCC cell lines after treating with gefitinib. Overexpression of linc01014 significantly inhibited the apoptosis of FLO‐1 cells induced by gefitinib and silencing linc01014 obviously promoted the apoptosis of FLO‐1 cells induced by gefitinib. Silencing linc01014 could significantly increase the gefitinib chemotherapy sensitivity of oesophagus cancer via PI3K‐AKT‐mTOR signalling pathway. 相似文献
84.
Qin Zhou Fan Zhao Ze-ping Lv Chen-guang Zheng Wei-dong Zheng Liang Sun Na-na Wang Shenghang Pang Fabiana Michelsen de Andrade Mian Fu Xiang-hua He Juan Hui Wen-yu Jiang Chu-yu Yang Xiao-hong Shi Xiao-quan Zhu Guo-fang Pang Yi-ge Yang Hai-qun Xie Wan-dong Zhang Cai-you Hu Ze Yang 《PloS one》2014,9(1)
Background
Previous association studies examining the relationship between the APOC1 polymorphism and susceptibility to Alzheimer’s disease (AD) have shown conflicting results, and it is not clear if an APOC1 variant acts as a genetic risk factor in AD etiology across multiple populations.Methods
To confirm the risk association between APOC1 and AD, we designed a case-control study and also performed a meta-analysis of previously published studies.Results
Seventy-nine patients with AD and one hundred fifty-six unrelated controls were included in case-control study. No association was found between the variation of APOC1 and AD in stage 1 of our study. However, our meta-analysis pooled a total of 2092 AD patients and 2685 controls. The APOC1 rs11568822 polymorphism was associated with increased AD risk in Caucasians, Asians and Caribbean Hispanics, but not in African Americans. APOE ε4 carriers harboring the APOC1 insertion allele, were more prevalent in AD patients than controls (χ2 = 119.46, OR = 2.79, 95% CI = 2.31–3.36, P<0.01).Conclusions
The APOC1 insertion allele, in combination with APOE ε4, likely serves as a potential risk factor for developing AD. 相似文献85.
Enantioselective liquid–liquid extraction of homophenylalanine (Hph) enantiomers was investigated with metal-BINAP complexes as enantioselective extractants. The metal complexes were synthesized by the complexation of (s)-2,2′-Bis(diphenylphosphino)-1,1′-binaphthalene (BINAP) with different central ions, among which, copper(I) complex allowed the separation of the Hph enantiomers with the highest operational selectivity. Efficiency of the extraction depends, often strongly, on a number of process variables, including types of organic solvents, pH of the aqueous phase, concentration of host and substrate, and temperature. In order to better understand the extraction process, equilibrium of the system were modeled by a homogeneous reaction model and an interfacial reaction model, respectively. Important parameters required by the modeling, such as complexation equilibrium constant and physical distribution coefficients were determined experimentally. When coupled with the parameters, extraction performance can be predicted by the models. Comparison between the experimental values and the model predictions indicates that the homogeneous reaction model can predict more accurately. By modeling and experiment, an optimal extraction condition concerning pH of 8 and host concentration of 2 mmol/L was obtained with high enantioselective (α) of 1.837 and performance factor (pf) of 0.086. 相似文献
86.
Wang B Fu S Zhang Y Xue Y Yang H Chen B Sun Y Zhang Y Li P 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2000,58(3):259-262
The allelic distribution of the Y-chromosome specific microsatellite DYS19 in the Han population and in the Daur, Oroqen and Ewenki ethnic groups (Northeast China) was analyzed by PCR and denatured polyacrylamide gel electrophoresis. The allelic distribution in the Han population group is as follows: A = 2.90%, B = 26.09%, C = 26.09%, D = 29.98%, E = 15.94%. This allelic distribution differs statistically significant from that observed in the three other ethnic groups (p < 0.05). Furthermore the polymorphism of the Y-chromosome specific Alu insert sequence DYS287 was tested in these four groups. However, no Alu sequence insert was found. 相似文献
87.
Genetic diversity and population history of the red panda (Ailurus fulgens) as inferred from mitochondrial DNA sequence variations 总被引:9,自引:0,他引:9
The red panda (Ailurus fulgens) is one of the flagship species in worldwide conservation and is of special interest in evolutionary studies due to its taxonomic uniqueness. We sequenced a 236-bp fragment of the mitochondrial D-loop region in a sample of 53 red pandas from two populations in southwestern China. Seventeen polymorphic sites were found, together with a total of 25 haplotypes, indicating a high level of genetic diversity in the red panda. However, no obvious genetic divergence was detected between the Sichuan and Yunnan populations. The consensus phylogenetic tree of the 25 haplotypes was starlike. The pairwise mismatch distribution fitted into a pattern of populations undergoing expansion. Furthermore, Fu's F(S) test of neutrality was significant for the total population (F(S) = -7.573), which also suggests a recent population expansion. Interestingly, the effective population size in the Sichuan population was both larger and more stable than that in the Yunnan population, implying a southward expansion from Sichuan to Yunnan. 相似文献
88.
分布在我国西南地区的横坑切梢小蠹,云南切梢小蠹和短毛切梢小蠹同域危害寄主云南松,给林业生产带来巨大损失。为探讨同域切梢小蠹种群在共存下对其空间分布格局的影响,采用传统聚集指标法和地统计学方法研究了三者在梢转干期不同受害云南松纯林树冠中的空间分布型。结果表明重度受害样地中云南切梢小蠹种群密度显著高于横坑切梢小蠹,在轻度受害样地则相反;传统聚集指标法结果显示同域共存的3种切梢小蠹种群在不同受害程度云南松中均为聚集分布,横坑切梢小蠹和云南切梢小蠹聚集是由环境因素和昆虫本身的聚集习性引起;地统计学结果表明除重度受害样地中短毛切梢小蠹呈随机分布外,其余切梢小蠹在不同种群密度下均呈聚集分布;除重度受害样地横坑切梢小蠹外,其他小蠹的空间依赖范围为4.01—7.45 m。横坑切梢小蠹和云南切梢小蠹在不同受害林分中拟合的半变异函数模型在球形模型和高斯模型之间转换。同域共存关系不影响不同种群密度下的切梢小蠹种群空间分布类型,但影响其半变异函数模型和理论参数。 相似文献
89.
Kai Song Brett H. Herzog Jianxin Fu Minjia Sheng Kirk Bergstrom J. Michael McDaniel Yuji Kondo Samuel McGee Xiaofeng Cai Ping Li Hong Chen Lijun Xia 《The Journal of biological chemistry》2015,290(33):20159-20166
Mucin-type core 1-derived O-glycans, one of the major types of O-glycans, are highly expressed in mammary gland epithelium. Abnormal O-glycans such as Tn antigen are found in over 90% of breast cancers; however, the in vivo role of these aberrant O-glycans in the etiology of breast cancer is unclear. We generated mice with mammary epithelial specific deletion of core 1-derived O-glycans. By crossing with two spontaneous mouse breast cancer models, we determined that loss of core 1-derived O-glycans delays the onset and progression of breast cancer development. Deficiency of core 1 O-glycosylation impaired the localization of Muc1, a major O-glycoprotein, on the apical surfaces of mammary epithelium. Signaling mediated by Muc1, which is critical for breast cancer development, was also defective in the absence of core 1 O-glycans. This study reveals an unexpected role of core 1-derived O-glycans in breast cancer development in mice. 相似文献