Association of Angiotensin-Converting Enzyme Genotype, Insertion/Deletion Polymorphism and Saphenous Vein Graft Atherosclerosis in Iranian Patients

ABSTRACT OBJECTIVE: The aim of this study was to evaluate possible interactions among Angiotensin-I converting enzyme genotype, insertion/deletion polymorphism and atherosclerosis of vein grafts in Iranian patients, and characterize their clinical and demographic profile. METHODS: In this cross-sectional study, patients who underwent coronary artery bypass graft surgery more than five years ago, were included for angiographic analysis. Atherosclerosis was determined by quantitative angiography and adjusted Gensini score. The gene angiotensin converting enzyme I/D polymorphism was detected by polymerase chain reaction. RESULTS: A total of 102 patients participated in this study. Eighty-four patients were male. The frequency distribution of DD, ID and II polymorphism were 23.6%, 62.7% and 13.7% respectively. There were no differences among genotypic groups in age, sex, number of risk factors, number of vein grafts and months since bypass surgery. According to adjusted Gensini score [0.18±0.12 (II) vs. 0.11±0.09 (ID) and 0.1±0.09 (DD) P=0.021] the II genotype was associated with severity of vein graft atherosclerosis. CONCLUSION: Although there are conflicting results about gene angiotensin converting enzyme I/D polymorphism and the degree of venous bypass graft degeneration, this study suggests an association between ACE genotype II and atherosclerosis of saphenous vein grafts, however, large samples considering clinical, demographic and ethnic profile are necessary to confirm these results.

Isolation and Characterization of a New Thermoalkalophilic Lipase from Soil Bacteria.

Lipases are diversified enzymes in their properties and substrate specificity, which make them attractive tools for various industrial applications. In this study, an alkalinethermostable lipase producing bacteria were isolated from soil of different regions of Isfahan province (Iran) and its lipase was purified by ammonium sulfate precipitation and ion exchange chromatography. To select a thermoalkalophil lipase producing bacterium, Rhodamine B and Horikoshi media were used and the strain that can grow at 45° Cwas selected. The isolated strain was identified using microbial and biochemical tests. One strain showed an orange colored zone on plate and grew on Horikoshi plate. Microbial and biochemical tests showed that the isolated strain was Bacillus subtilis, a Gram positive rod. In PCR, an expected band was obtained with about 371 bp. The activity of the purified lipase was 10.2 folds that of the standard enzyme using ammonium sulfate precipitation and ion exchange chromatography. The molecular weight of lipase determined by SDS-PAGE electrophoresis, was 21 and 35 KDa. Existence of two bands in SDS-PAGE electrophoresis and low amount of obtained purified enzyme highlights the necessity of optimization of purification and concentrating process.

Association of Angiotensin-Converting Enzyme Genotype, Insertion/Deletion Polymorphism and Saphenous Vein Graft Atherosclerosis in Iranian Patients.

OBJECTIVE: The aim of this study was to evaluate possible interactions among Angiotensin-I converting enzyme genotype, insertion/deletion polymorphism and atherosclerosis of vein grafts in Iranian patients, and characterize their clinical and demographic profile. METHODS: In this cross-sectional study, patients who underwent coronary artery bypass graft surgery more than five years ago, were included for angiographic analysis. Atherosclerosis was determined by quantitative angiography and adjusted Gensini score. The gene angiotensin converting enzyme I/D polymorphism was detected by polymerase chain reaction. RESULTS: A total of 102 patients participated in this study. Eighty-four patients were male. The frequency distribution of DD, ID and II polymorphism were 23.6%, 62.7% and 13.7% respectively. There were no differences among genotypic groups in age, sex, number of risk factors, number of vein grafts and months since bypass surgery. According to adjusted Gensini score [0.18±0.12 (II) vs. 0.11±0.09 (ID) and 0.1±0.09 (DD) P=0.021] the II genotype was associated with severity of vein graft atherosclerosis. CONCLUSION: Although there are conflicting results about gene angiotensin converting enzyme I/D polymorphism and the degree of venous bypass graft degeneration, this study suggests an association between ACE genotype II and atherosclerosis of saphenous vein grafts, however, large samples considering clinical, demographic and ethnic profile are necessary to confirm these results.

EphB4 tyrosine kinase stimulation inhibits growth of MDA-MB-231 breast cancer cells in a dose and time dependent manner.

BACKGROUND: EphB4 receptor tyrosine kinase is of diagnostic and therapeutic value due to its overexpression in breast tumors. Dual functions of tumor promotion and suppression have been reported for this receptor based on presence or absence of its ligand. To elucidate such discrepancy, we aimed to determine the effect of time- and dose-dependent stimulation of EphB4 on viability and invasion of breast cancer cells via recombinant ephrinB2-Fc. METHODS: Cells were seeded into multiwell plates and were stimulated by various concentrations of preclustered ephrinB2-Fc. Cell viability was measured on days 3 and 6 following treatment using alamar-blue when cells were in different states of confluence. RESULTS: Stimulation of cells with ephrinB2 did not pose any significant effect on cell viability before reaching confluence, while inhibition of cell growth was detected after 6 days when cells were in postconfluent state following a dose-dependent manner. EphrinB2 treatment did not affect tubular formation and invasion on matrigel. CONCLUSION: This study showed that EphB4 can differentially inhibit cells at post confluent state and that presence of ligand manifests growth-inhibitory properties of EphB4 receptor. It is concluded that growth inhibition has occurred possibly due to long treatment with ligand, a process which leads to receptor downregulation.