MMP 9 Gene Promoter Polymorphism in Gastric Cancer

Matrix metalloproteinase-9 (gelatinase B) plays a key role in cancer invasion and metastasis by degrading the extracellular matrix and basement membrane barriers. A cytosine (C) > thymidine (T) single nucleotide polymorphism (SNP) at position −1562 in the MMP-9 promoter is reported to influence the expression of the gene. Genotyping of MMP-9 −1562 C→T promoter polymorphism in 140 gastric cancer patients and 132 healthy control subjects was carried out in order to evaluate its association with progression and development of gastric cancer. The SNP was genotyped by tetra-primer amplification refractory mutation system-polymerase chain reaction followed by agarose gel electrophoresis. Statistical methods were adopted to test for the significance of the results. Risk factor profile of the patients revealed age above 50 years, smoking, alcoholism as the factors associated with the disease. The distribution of genotype frequencies in gastric cancer patients were 28.7 % of CC, 45.5 % of CT and 25.7 % of TT, whereas in control subjects 31.8 % of CC, 53.03 % of CT and 15.15 % of TT, respectively. The allelic frequencies were 51.51 % of C and 48.48 % of T in patient group and 58.33 % of C and 41.66 % of T in controls respectively. The present study shows the possible association of epidemiological risk factors with gastric cancer. There is an increased frequency of T allele in the disease compared to control subjects. However, there is no association of the MMP-9 −1562 C→T promoter polymorphism in the development of gastric cancer.     

C++中的多态性研究

多态性特征是C++中最为重要的一个特征。在分析研究了C++的多态性特征后,总结并给出了准确理解和掌握多态性特征的几个必要的技术概念及其实现要点,结合实际开发经验,提出了解决多态性的方案。     

Impact of CCL2 and Its Receptor CCR2 Gene Polymorphism in North Indian Population: A Comparative Study in Different Ethnic Groups Worldwide

Chemokine are small, inducible pro-inflammatory cytokines involved in many biological processes, such as migration of leukocytes, atherosclerosis, angiogenesis, tumor growth, and metastasis. Chemokine are also known to influence tumor cell’s activity. Specifically, tumor cells express chemokine receptors in a non random manner suggesting a role of chemokine in metastatic destination of tumor cells. The present study was conducted to determine distribution of (Chemokine receptor 2) CCR2 V64I, Chemokine ligand 2 CCL2 I/D, and CCL2 2518 A>G gene polymorphisms in North Indian population and compare with different populations globally. Polymerase chain reaction (PCR)-based analysis was conducted in 200 normal healthy individuals of similar ethnicity. Allelic frequencies in wild type (GG) of CCR2 V64I G>A were 63 % G; CCL2 I/D 42 % II; CCL2 2518 A>G 40.5 % A. The minor variant allele frequency in our population was as follows: 19.5 % for CCR2 V64I, 35.5 % for CCL2 I/D, 35.3 % for CCL2 2518 A>G. We further compared frequency distribution for these genes with various published studies in different ethnicity. Our results suggested that frequency in chemokine genes exhibit distinctive pattern in India that could be attributed to ethnicity variation. This could assist in high-risk screening of human exposed to environmental carcinogens and cancer predisposition in different ethnic groups. Thus, they signify an impact of ethnicity and provide a basis for future epidemiological and clinical studies.     

在C++中实现运行时的多态性过程的研究

介绍了实现运行时的多态性几个重要因素——虚函数、基类和派生类。通过实例阐述了虚函数如何实现运行时的多态性的,用运行结果数据详细分析了运行时的多态性的过程。最后说明了动态绑定实现的原理。     

CRISPR/Cas9-mediated MSTN gene editing induced mitochondrial alterations in C2C12 myoblast cells

BackgroundMyostatin (MSTN) negatively regulates muscle mass and is a potent regulator of energy metabolism. However, MSTN knockout have affect mitochondrial function. This research assessed the mitochondrial energy metabolism of Mstn −/+ KO cells, and wondered whether the mitochondria biogenesis are affected.ResultsIn this study, we successfully achieved Mstn knockout in skeletal muscle C2C12 cells using a CRISPR/Cas9 system and measured proliferation and differentiation using the Cell-Counting Kit-8 assay and qPCR, respectively. We found that MSTN dysfunction could promote proliferation and differentiation compared with the behaviour of wild-type cells. Moreover, Mstn KO induced an increase in KIF5B expression. The mitochondrial content was significantly increased in Mstn KO C2C12 cells, apparently associated with the increases in PGC-1α, Cox1, Cox2, ND1 and ND2 expression. However, no differences were observed in glucose consumption and lactate production. Interestingly, Mstn KO C2C12 cells showed an increase in IL6 and a decrease in TNF-1α levels.ConclusionThese findings indicate that MSTN regulates mitochondrial biogenesis and metabolism. This gene-editing cells provided favourable evidence for animal breeding and metabolic diseases.How to cite: Wang L, Ding Q, Ma S, et al. CRISPR/Cas9-mediated MSTN gene editing Induced Mitochondrial Alterations in C2C12 myoblast Cells. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.03.009     

基于遗传算法的电梯群控研究

针对电梯群控系统的特点,设计出一种更适合的梯群控制的遗传算法.本算法中采用了整数编码和可进行种群竞争的双种群机制,设计了以候梯时间、乘梯时间、系统能耗为群控目标的多目标适应度函数.并在选择操作中引入个体最优选择策略,在交叉操作中构造了与遗传代的数目、预交叉个体本身特点相结合的交叉方式,在变异操作中应用了两点对换和位点变异相结合的变异方法,并设计了从最优解集合中选择最优解的评价函数.经过模拟仿真,运行实验结果表明了此方案的可行性和优越性.     

基于遗传算法的工程项目群工期-费用优化研究

首先根据项目群工期与费用的特点分析项目群工期与费用优化机理;然后在工程质量得以保障的假设前提下构建项目群工期-费用优化模型,依据遗传算法原理对模型进行求解;最后引入大型工程项目群案例进行项目群工期-费用优化实证分析。研究结果显示:利用实数编码以及保留精英子代的遗传算法能直观而又准确地解决项目群费用的优化问题,同时达到在一定程度上缩短工期的效果。     

Methylenetetrahydrofolate Reductase C677T Polymorphism and Risk for Male Infertility in Asian Population

Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme of folate pathway and required for DNA synthesis and methylation. MTHFE C677T polymorphisms is reported as risk factors for various diseases and disorders like birth defects, metabolic, neurological, psychiatric disorders, and cancers. Several studies have investigated association between the MTHFR C677T polymorphism and male infertility. To assess the risk associated with MTHFR C677T polymorphism in Asian population, a meta-analysis was performed. Included articles were collected from the following electronic databases: PubMed, Google Scholar, and Science direct up to March 2015. Risk was estimated as pooled odds ratios (ORs) with confidence intervals (CIs) for assessment. Seventeen case–control studies involving 4392 breast infertile males and 3667 fertile males were found suitable for the inclusion in the present meta-analysis. Results showed that the C677T polymorphism was significantly associated with male infertility in Asian population using all the five genetic models (OR_{T vs. C} (allele contrast model) = 1.86, 95% CI 1.7–2.0; OR_{TT vs. CC} (homozygote model) = 1.96, 95% CI 1.67–2.30; OR_{CT vs. CC} (co-dominant model) = 1.40, 95% CI 1.18–1.62; OR_{TT+CT vs. CC} (dominant model) = 1.53, 95% CI 1.30–1.77; OR_{TT vs. CT+CC} (recessive model) = 1.67, 95% CI 1.44–1.92). In conclusion, results of present meta-analysis strongly supported an association between C677T polymorphism and male infertility in Asians.     

中国民族地区遗传资源及传统知识的保护与惠益分享

遗传资源及相关传统知识的保护与惠益分享已成为国际生物多样性和知识产权等论坛的重要热点议题。《生物多样性公约》（CBD）正在谈判建立遗传资源及相关传统知识获取与惠益分享的国际制度。中国广大少数民族地区遗传资源及相关传统知识非常丰富。但由于大规模经济开发和外来文化渗透,遗传资源和传统知识正面临丧失威胁。本文根据中国实际,阐述了与生物多样性相关传统知识的概念与范畴;介绍了国际上有关遗传资源和相关传统知识“生物剽窃”的案例背景;分析了《生物多样性公约》等国际论坛在建立遗传资源及相关传统知识获取与惠益分享国际制度方面的谈判进展。并针对中国在传统知识保护方面存在的问题,提出加强遗传资源及相关传统知识保护的行动措施。     

C++在ARM9体系中的开发与应用研究

本文阐述了C++在ARM9体系中的应用研究,并介绍了C++编程语言以及嵌入式系统,分析了如何在嵌入式应用中编写优秀的C++代码,最后简要分析了C++在嵌入式领域中的发展前景.     

C677T MTHFR Gene Polymorphism is Contributing Factor in Development of Renal Impairment in Young Hypertensive Patients

Homocysteine concentration affected by the activities of the enzymes methylene tetra-hyrdofolate reductase (MTHFR). Polymorphisms in MTHFR gene associated with an impairment of MTHFR activity. Hyperhomocysteinemia is a result of single nucleotide polymorphisms (SNPs) in MTHFR 677 C>T that can cause homocysteine levels in the blood to increase. The purpose of this study is to investigate the relationships between MTHFR C677T (rs1801133) gene polymorphism, changes in homocysteine concentrations and progress of renal impairment in young adult hypertensive patients. Two hundred young hypertensive patients (age 21–24 years) were involved in this study; they were classified into patients with and without renal impairment in addition to 200 age and sex matched healthy controls. All participants were submitted to laboratory investigations as assay of MTHFR gene polymorphism C677T (rs1801133) by PCR/RFLP, determination of lipid profile, homocysteine and folic acid concentrations in addition to urinary albumin creatinine ratio (UACR). The levels of both homocysteine and UACR in the TT genotype patients were higher than those in the CC genotype group. Individuals who carry the T allele were more risky to hypertension and progress to early renal impairment in young age compared with those carrying the C allele [OR 2.02 (1.33–3.08), P < 0.001]. Genetic variants of C677T MTHFR gene and hyperhomocysteinemia may be responsible for rapid progress of renal impairment in Egyptian young age hypertensive patients. TT genotype or T allele may be considered as a predisposing factor for both elevated Hcy levels and the development of renal impairment. This study believed that lowering of homocysteine level can reduce renal impairment of hypertensive patients.     

Haptoglobin Polymorphism and Association with Complications in Ghanaian Type 2 Diabetic Patients

There is scanty information on the role of genetic factors, especially those relating to haptoglobin (Hp) phenotypes in the expression of complications among diabetes mellitus patients in Ghana. In this study, we investigated whether there is any association between Hp phenotypes and diabetic complications and to determine if association of the Hp phenotypes with diabetic complications in Ghanaian diabetics differ from those in Caucasians. A total of 398 participants were randomly recruited into the study. These comprised diabetic patients numbering 290 attending a diabetes Clinic in Ghana and 108 non-diabetic controls from the same community. Analyses of the results indicate that most of the diabetics with complications were of the Hp 2–2 (35%) and Hp 2–1 (23.9%) phenotypes. Fewer diabetics were found to be of the Hp 2–1 M phenotype. The controls were mostly of Hp 1–1 and Hp 2–1 M phenotypes. The odds ratio of having complications in a diabetic with an Hp 2–2 phenotype was 18.27 times greater than that for Hp 0–0. Hp 2–2 phenotype with its poor antioxidant activity may therefore be a useful predictor for the propensity of an individual to develop diabetes complications.     

Folate Pathway Gene Methylenetetrahydrofolate Reductase C677T Polymorphism and Alzheimer Disease Risk in Asian Population

The association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and susceptibility to Alzheimers disease (AD) was controversial in previous studies. The present meta-analysis was designed to investigate the association of MTHFR C677T polymorphism with AD. Nine studies were identified by search of PubMed, Google Scholar, Elsevier, Springer Link databases, up to January 2013. Odds ratios (ORs) with corresponding 95 % confidence interval (CI) were calculated using fixed effects model or random effects model. All statistical analysis was done by Mix version 1.7. MTHFR C677T polymorphism had a significant association with susceptibility to AD in all genetic models (for T vs C: OR 1.29, 95 % CI 1.15–1.44, p < 0.0001; for TT + CT vs CC: OR 1.38, 95 % CI 1.16–1.364, p = 0.0002; for TT vs CC: OR 1.60, 95 % CI 1.25–2.04, p = 0.0001; for CT vs CC: OR 1.28, 95 % CI 1.1–1.53, p < 0.008; for TT vs CT + CC: OR 1.37, 95 % CI 1.12–1.67, p = 0.002). Results from present meta-analysis supported that the MTHFR C677T polymorphism was associated with an increased risk of AD in Asian population.     

Polymorphic Variation in Double Strand Break Repair Gene in Indian Population: A Comparative Approach with Worldwide Ethnic Group Variations

DNA repair capacity is essential in maintaining cellular functions and homeostasis. Identification of genetic polymorphisms responsible for reduced DNA repair capacity may allow better cancer prevention. Double strand break repair pathway plays critical roles in maintaining genome stability. Present study was conducted to determine distribution of XRCC3 Exon 7 (C18067T, rs861539) and XRCC7 Intron 8 (G6721T, rs7003908) gene polymorphisms in North Indian population and compare with different populations globally. The genotype assays were performed in 224 normal healthy individuals of similar ethnicity using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Allelic frequencies of wild type were 79% (C) in XRCC3 Exon 7 C > T and 57% (G) in XRCC7 Intron 8 (G > T) 57% (G) observed. On the other hand, the variant allele frequency were 21% (T) in XRCC3 Exon 7 C > T and 43% (T) in XRCC7 Intron 8 G > T respectively. Major differences from other ethnic populations were observed. Our results suggest that frequency in these DNA repair genes exhibit distinctive pattern in India that could be attributed to ethnicity variation. This could assist in high-risk screening of humans exposed to environmental carcinogens and cancer predisposition in different ethnic groups.     

基于B2B、B2C、C2C的第三方网上支付研究

研究第三方网上支付理论的基础上,对三种典型的电子商务B2B、B2C、C2C的第三方网上支付进行了比较分析,总结了基于B2B、B2C、C2C的第三方网上支付系统模式及其存在的问题,最后规划了第三方协同网上支付的构建模式及其特性。     

技术接受模型在中国C2C电子商务网站中的研究

通过分析技术接受模型和我国目前电子商务网站的特点,本文提出一种适用于C2C电子商务网站的改进的技术接受模型.该模型能够清楚描述整个交易流程,还能够说明交易过程和信用评价体系之间的相关性.此外,借鉴需求层次理论对该模型所体现出的消费者需求进行了解释.该模型的建立有助于指导消费者选择合适的交易对象,挖掘潜在消费者,而且也为保证交易顺利实现提供了一定依据.     

Methylenetetrahydrofolate Reductase C677T Polymorphism and Recurrent Pregnancy Loss Risk in Asian Population: A Meta-analysis

The C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene was implicated to be associated with thrombophilia due to its role in catalyzing the formation of 5-methylenetetrahydrofolate, a co-substrate for the conversion of homocysteine to methionine. Several case–control studies were investigated MTHFR C677T polymorphism as risk for recurrent pregnancy loss (RPL). These studies rendered contradictory results, some indicating that the polymorphism is associated with the risk of RPL whereas others concluded there is no association. To shed light on these inconclusive findings, a meta-analysis of all available studies published from Asian population relating the C677T polymorphism to the risk of RPL was conducted. The following electronic databases were searched without language restrictions: PubMed, Google Scholars, Elsevier and Springer Link up to December, 2015. Meta-analysis was performed using MetaAnalyst and Mix version 1.7. Meta-analysis results suggested that MTHFR C677T polymorphism contributed to the increased RPL risk in Asian population using all five genetic models (for T vs. C: OR 1.35, 95 % CI 1.09–1.68, p = 0.009; for TT + CT vs. CC: OR 1.44, 95 % CI 1.14–1.82, p = 0.006; for CT vs. CC: OR 1.39, 95 % CI 1.07–1.8, p = 0.01; for TT vs. CC: OR 1.79, 95 % CI 1.23.2.6, p = 0.007; for TT vs. CT + CC: OR 1.61, 95 % CI 1.02–2.56, p = 0.04). In conclusion, this meta-analysis demonstrates a strong association between the MTHFR C677T variant and RPL in Asian population and raising the importance of the use of folate in its treatment and prevention.     

浅议B2C及C2C电子商务支付方式的问题及对策

电子商务为中国经济的发展营造了良好的氛围,也对社会各领域提出了新的挑战。随着电子商务的发展,电子支付系统正在改变着人们的生活方式,但也不可避免地存在着许多缺陷。从中国电子商务的发展现状和所存在的问题对电子商务支付产生的影响出发,对中国特色的B2C和C2C电子商务支付方式做出分析,并结合中国电子商务发展和网上支付运行现状提出可能的解决途径。