Relationship between endothelial nitric oxide synthase gene polymorphisms and the risk of myocardial infarction in the Algerian population

Introduction: Endothelial nitric oxide synthase (eNOS), the enzyme in charge of nitric oxide production, plays a crucial role in vascular biology. However, the impact of single nucleotide polymorphisms (SNPs) affecting the gene encoding for eNOS (eNOS) on coronary artery diseases remains under debate and no data were available at present in populations originating from Mahghreb.Aim of the Study: Our purpose was to evaluate the association between the eNOS -786T/C and +894G/T SNPs and (i) the risk of myocardial infarction (MI) and (ii) variations in systolic (SBP) and diastolic (DBP) blood pressure values.Patients and Methods: Concerning MI, the SNPs were characterised in a casecontrol study (70 cases vs 68 controls) based on the male population originating from Oran, Algeria.Results: The associations with blood pressure values were assessed in anenlarged control group including 115 male subjects. Since the -786T/CSNP could not be associated to MI, the genotype distribution of the+894G/T genotypes signifi cantly differed between MI cases and controls(p=0.025). The risk of MI (odds ratio) associated to the +894G/T SNP wasestimated to 1.2 (95%CI=[1.03;1.32]). The haplotype analysis confi rmedthis association and the absence of impact of the -786T/C SNP. On the other hand, no consistent association was shown between the two SNPs and SBP or DBP.Conclusion: As observed in other populations, the eNOS +894G/T SNPwas associated with MI in the Algerian population but the mechanismunderlying the effect could not be related to variations in blood pressure.Keywords: Endothelial nitric oxide synthase, myocardial infarction, blood pressure, genetic epidemiology

Dynamic replication strategies in data grid systems: A survey

In data grid systems, data replication aims to increase availability, fault tolerance, load balancing and scalability while reducing bandwidth consumption, and job execution time. Several classification schemes for data replication were proposed in the literature, (i) static vs. dynamic, (ii) centralized vs. decentralized, (iii) push vs. pull, and (iv) objective function based. Dynamic data replication is a form of data replication that is performed with respect to the changing conditions of the grid environment. In this paper, we present a survey of recent dynamic data replication strategies. We study and classify these strategies by taking the target data grid architecture as the sole classifier. We discuss the key points of the studied strategies and provide feature comparison of them according to important metrics. Furthermore, the impact of data grid architecture on dynamic replication performance is investigated in a simulation study. Finally, some important issues and open research problems in the area are pointed out

Adsorption Kinetics of Cellulase and Xylanase Immobilized on Magnetic Mesoporous Silica

The adsorption kinetics of cellulase and xylanase immobilized on magnetically separable, hierarchically ordered mesocellular mesoporous silica (M-HMMS) was investigated. The adsorption of cellulase on M-HMMS followed pseudo-second-order kinetics while the xylanase adsorption followed the Avrami model. Intraparticle and film diffusion also affected this process. These results enable in-depth knowledge of the cellulase and xylanase adsorption mechanisms on M-HMMS for better future applications by improving the stability of the immobilization