Alper Sonmez
Gulhane Military Medical Academy, Endocrinology and Metabolism, Faculty Member
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Hemoglobin (Hb) regulates the endothelial function by modulating the bio-availability of NO at the tissue level. A significant direct relationship is present between the Hb levels and endothelial functions in patients with Type 2... more
Hemoglobin (Hb) regulates the endothelial function by modulating the bio-availability of NO at the tissue level. A significant direct relationship is present between the Hb levels and endothelial functions in patients with Type 2 diabetes. Testing whether this association also exists in subjects with prediabetes is important because prediabetes is associated with an increased risk of cardiovascular disease and mortality. Therefore, we investigated the association of Hb both with the classical cardiac risk factors and the markers for endothelial dysfunction and inflammation, in subjects with impaired glucose tolerance (IGT). We enrolled 69 normotensive, and cardiovascular events free subjects with IGT (M=40, age=45.50+/-6.8 yr). Plasma insulin, hsCRP, soluble CD40L, vonWillebrand factor, p-selectin levels were measured. The parameters given according to the higher and lower median Hb values of the subjects were compared. Subjects with the higher Hb levels exhibited lower HDL-C (46.68...
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Özet: Araştirmanin amaci, Aydin il merkezinde doğum öncesi bakim (DÖB) hizmetlerini nicelik ve nitelik olarak değerlendirmektir. Araştirma kesitsel tiptedir. Aydin merkezinde yaşayan 195 kadin (gebe/lohusa) araştirmaya katilmiştir.... more
Özet: Araştirmanin amaci, Aydin il merkezinde doğum öncesi bakim (DÖB) hizmetlerini nicelik ve nitelik olarak değerlendirmektir. Araştirma kesitsel tiptedir. Aydin merkezinde yaşayan 195 kadin (gebe/lohusa) araştirmaya katilmiştir. Kadinlar, il merkezindeki 10 sağlik ocağindan, (her bir sağlik ocağindan bir kirsal ve bir kentsel sağlik evi olacak şekilde) basit rastgele ve küme örneklem metoduyla seçilmiştir. Veri yüz yüze anket yöntemiyle toplanmiştir. Türkiye
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Secondary amyloidosis is the most important complication of FMF and endothelial function is more severely impaired. Elevated asymmetric dimethyl arginine (ADMA) may mediate the excess cardiovascular disease (CVD) risk of this group. We... more
Secondary amyloidosis is the most important complication of FMF and endothelial function is more severely impaired. Elevated asymmetric dimethyl arginine (ADMA) may mediate the excess cardiovascular disease (CVD) risk of this group. We aimed to compare endothelial function characteristics, including ADMA, in patients with FMF-related amyloidosis and primary glomerulopathies and to define risk factors for a CVD event. We undertook a cross-sectional study with prospective follow-up including consecutive patients with FMF-related amyloidosis (n = 98) or other non-diabetic glomerulopathies (n = 102). All patients had nephrotic-range proteinuria and normal glomerular filtration rate. Flow-mediated dilatation (FMD) was assessed and ADMA levels, CRP and pentraxin 3 (PTX3) were determined. Patients were followed for cardiovascular events. Amyloidosis patients secondary to FMF showed higher levels of ADMA, CRP and PTX3 and lower FMD as compared with patients with other glomerulopathies. Card...
Research Interests: Rheumatology, Immunology, Turkey, Adolescent, Prospective studies, and 20 moreHumans, Blood Pressure, Female, Male, Young Adult, Follow-up studies, Vascular endothelium, Incidence, Risk factors, Clinical Sciences, Middle Aged, Adult, Public health systems and services research, Prognosis, Cardiovascular Diseases, Risk Factors, Cross Sectional Studies, Vasodilation, Amyloidosis, and Familial Mediterranean Fever
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Research Interests: Immunohistochemistry, Public Health, Insulin Resistance, Humans, Liver, and 16 moreFemale, Male, Hepatitis, Animal Model, Clinical Sciences, Nonalcoholic steatohepatitis, Middle Aged, Fatty Liver, Adult, Protein Expression, Biological markers, Enzyme Linked Immunosorbent Assay, Case Control Studies, Cohort Studies, The American, and Interleukin
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Research Interests: Kidney transplantation, Treatment Outcome, Transplantation, Lipids, Tacrolimus, and 16 moreRenal transplantation, Prospective studies, Humans, Blood Glucose, Blood Pressure, Female, Male, Cyclosporine, C reactive protein, Endothelial Function, Adult, Arginine, Biological markers, Serum Asymmetric Dimethylarginine (ADMA), Chronic Kidney Failure, and Cohort Studies
Endothelial dysfunction (ED) has a major role in the cardiovascular outcome of patients with chronic kidney disease (CKD). The aim of this study was to investigate the relation between fetuin A levels and ED in kidney transplant... more
Endothelial dysfunction (ED) has a major role in the cardiovascular outcome of patients with chronic kidney disease (CKD). The aim of this study was to investigate the relation between fetuin A levels and ED in kidney transplant recipients. Forty-two living donor kidney transplant recipients, 21 (11 male) on cyclosporine A and 21 (10 male) on tacrolimus-based regimes, were studied. Forty-two (21 male) healthy subjects were enrolled as controls. Fetuin A, highly sensitive C-reactive protein (hsCRP) levels, brachial artery endothelium-dependent vasodilatation (FMD), nitroglycerine mediated dilatation (NMD), and carotid intima-media thickness (CIMT) were measured before transplantation and on the 30th and 90th days posttransplant. Pretransplantation serum fetuin A concentrations and FMD values of patients were significantly lower than those of the controls (P<0.001 for both). These were significantly increased in the 30th and 90th days posttransplantation There was a significant positive correlation between Fetuin A and FMD levels both before and after kidney transplantation (r=0.534, r=0.576; respectively, P<0.001 for both). Carotid intima-media thickness and hsCRP levels decreased after transplantation (P<0.001 for all). According to the regression analysis, fetuin A, intact parathyroid hormone, and hsCRP levels were the independent determinants of FMD. The results of the present study suggest that low serum fetuin A levels in CKD may contribute to impaired endothelial functions in CKD. Future studies should clarify the role of fetuin A levels in cardiovascular outcomes of CKD.
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Research Interests: Chronic kidney disease, Humans, Ultrasonography, Female, Male, and 15 moreVascular endothelium, Medical Physiology, Risk factors, Endothelial dysfunction, Parathyroid Hormone, Clinical Sciences, Endothelial Function, High Resolution, Adult, Multiple regression analysis, Biological markers, Risk Factors, The Carotid Artery Intima Media Thickness, Chronic Kidney Failure, and Blood Proteins
Diabetic nephropathy (DN) is a major manifestation of microangiopathy in patients with Diabetes Mellitus (DM). Inflammation is one of the major factors in the formation of endothelial dysfunction. Endothelial dysfunction is a major... more
Diabetic nephropathy (DN) is a major manifestation of microangiopathy in patients with Diabetes Mellitus (DM). Inflammation is one of the major factors in the formation of endothelial dysfunction. Endothelial dysfunction is a major contributor to the complications of DM. The aim of the present study was to investigate the possible relationship between inflammation, endothelial dysfunction and proteinuria in patients with diabetic nephropathy. Plasma TNF-α and IL-6, pro-inflammatory cytokines, concentrations were measured in 25 patients with DN and in 30 diabetic control subjects. Also, we evaluated the markers of endothelial dysfunction such as flow mediated dilatation (FMD), nitrate-mediated dilatation (NMD) and carotid intima-media thickness (CIMT). TNF-α, IL-6 and high-sensitivity C-reactive protein concentrations were significantly higher (p = 0.012, p = 0.006 and p < 0.001, respectively) in the patients with DN than the controls. And, urinary protein concentrations were significantly higher (p < 0.001) but eGFR levels were significantly lower (p < 0.001) in the patients with DN. FMD was significantly lower in DN patients (p < 0.001). We have observed that FMD correlated negatively with body mass index (r = -0.424, p < 0.05). And there was also a positive correlation between TNF-α and urinary protein concentrations in the patients with DN (p < 0.05). TNF-α, IL-6, hsCRP and urinary protein concentrations are higher in the DN patients. There were no correlations among pro-inflammatory cytokines concentrations and markers of vascular endotelial disfunction. These findings did not show vascular endothelial dysfunction, but may indicate glomerular endothelial dysfunction.
Research Interests: Inflammation, Humans, Diabetes mellitus, Female, Clinical, and 15 moreMale, Clinical Sciences, Middle Aged, C reactive protein, Diabetes complications, Tumor necrosis factor-alpha, Blood Vessels, Biological markers, The Carotid Artery Intima Media Thickness, Proteinuria, ENDOTHELIUM, Vasodilation, Enzyme Linked Immunosorbent Assay, Interleukin, and Glomerular Filtration Rate
Adiponectin appears to be an important modulator for metabolic and vascular diseases. A case-controlled study was designed to measure plasma adiponectin levels and investigate the effects of rosiglitazone on adiponectin levels in type 2... more
Adiponectin appears to be an important modulator for metabolic and vascular diseases. A case-controlled study was designed to measure plasma adiponectin levels and investigate the effects of rosiglitazone on adiponectin levels in type 2 diabetic patients with proteinuria. Sixty-four patients (mean age, 46.1±4.6 yr; 30 male, 34 female) and 26 healthy volunteers (mean age, 45.3±4.8 yr; 14 male, 12 female)
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Research Interests: Kidney diseases, Chronic kidney disease, Inflammation, Multivariate Analysis, Insulin Resistance, and 14 moreHumans, Chronic Disease, Female, Male, Vascular endothelium, Endothelial dysfunction, Clinical Sciences, Middle Aged, Adiponectin, Adult, Biological markers, Vasodilation, Case Control Studies, and Glomerular Filtration Rate
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Research Interests: Cardiovascular Risk, Humans, Blood Pressure, Female, Male, and 21 moreVascular endothelium, CVD, Endothelial dysfunction, Diabetic Nephropathy, Renal Function, Clinical Sciences, Middle Aged, Adiponectin, Peripheral Vascular Disease, Adult, Kidney Disease, Multivariate Regression, Cardiovascular Diseases, The Carotid Artery Intima Media Thickness, Proteinuria, Peptide hormones, Type 2 Diabetes Mellitus, Cross sectional Study, Case Control Studies, Brachial artery, and Glomerular Filtration Rate
Research Interests: Nephrology, Treatment Outcome, Metabolic syndrome, Insulin Resistance, Lipids, and 16 moreProspective studies, Humans, Hypertension, Blood Pressure, Female, Male, Body Mass Index, Clinical Sciences, Middle Aged, Adiponectin, Adult, Time Factors, Amlodipine, Angiotensin Converting Enzyme Inhibitors, Predictive value of tests, and Calcium Channel Blockers
Research Interests: Nephrology, Kidney diseases, Cytokines, Inflammation, Treatment Outcome, and 45 moreCell Division, Heart Failure, Insulin Resistance, Prospective studies, Humans, Hypertension, Collagen, Blood Pressure, Diuretics, Renin Angiotensin Aldosterone System, Chronic Disease, Female, Animals, Male, Heart, Vascular endothelium, Potassium, Fibrosis, Diabetic Nephropathy, Serum Creatinine, Hydrochlorothiazide, Clinical Sciences, Aged, Middle Aged, C reactive protein, Adult, Myocardium, Time Factors, Randomized Controlled Trial, Kidney Disease, Transforming Growth Factor Beta, Biological markers, Combination drug therapy, Disease Progression, Basic Cardiology, Proteinuria, Losartan, Vasodilation, Collagen Type IV, Cross-Over Studies, Renal disease, Angiotensin Converting Enzyme Inhibitors, Control Group, Plasminogen Activator Inhibitor, and Glomerular Filtration Rate
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Research Interests: Kidney diseases, Chronic kidney disease, Cardiovascular Risk, Insulin Resistance, Humans, and 22 moreKidney, Insulin, Chronic Disease, Female, Male, Regression Analysis, Body Mass Index, Risk factors, Clinical Sciences, C reactive protein, Peripheral Vascular Disease, Homeostasis, Adult, Arginine, Biological markers, Disease Progression, Risk Factors, Indexation, Proteinuria, Healthy Subjects, Case Control Studies, and Glomerular Filtration Rate
Research Interests: Nephrology, Urology, Kidney diseases, Chronic kidney disease, Dialysis, and 22 moreLinear models, Multivariate Analysis, Humans, Kidney, Nitric oxide, Chronic Disease, Female, Male, Risk factors, Fibroblast Growth Factor, Clinical Sciences, Middle Aged, Adult, Multiple regression analysis, Assessment Model, Arginine, Risk Factors, Indexation, Vascular Reactivity, Vasodilation, Forearm, and Glomerular Filtration Rate
Research Interests: Nephrology, Urology, Chronic kidney disease, Multivariate Analysis, Humans, and 20 moreProtein Turnover, Nitric oxide, Chronic Disease, Female, Male, The, Risk factors, Endothelial dysfunction, Clinical Sciences, Adult, Arginine, Risk Factors, Indexation, Proteinuria, ENDOTHELIUM, Cross sectional Study, Predictive value of tests, Amyloidosis, Glomerulonephritis, and Brachial artery
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Previous studies have demonstrated that elevated plasma leptin concentrations are associated with essential hypertension. It has also recently been shown that leptin plays a promoting role in angiogenesis, and the vascular endothelium... more
Previous studies have demonstrated that elevated plasma leptin concentrations are associated with essential hypertension. It has also recently been shown that leptin plays a promoting role in angiogenesis, and the vascular endothelium expresses the long form of leptin receptor. Those data led us to hypothesize that leptin might contribute to end-organ damage in hypertension. Thus, in the present study we evaluated the relationship between plasma leptin concentrations and hypertensive retinopathy (HR). One hundred and eleven patients newly diagnosed with essential hypertension [EHT; mean age, 43.5 +/-10.7 yr; body mass index (BMI), 28.1 +/- 4.4 kg/m2; male/female ratio, 71/40] and 79 healthy normotensive control subjects (NT; mean age, 43.6 +/- 9.2 yr; BMI, 28.2 +/- 3.3 kg/m2; male/female ratio, 50/29) were enrolled in the study. For the assessment of retinopathy according to the Keith-Wagener classification, direct and indirect ophthalmoscopy were performed in all subjects after dilatation of the pupils. Plasma leptin levels were significantly higher in EHT (11.8 +/- 11.1 ng/mL) than in NT (7.2 +/- 5.1 ng/mL) (P = 0.003). Plasma leptin concentrations were strongly correlated with BMI in both EHT (r = 0.45; P = 0.001) and NT (r = 0.38; P = 0.001) groups. Plasma leptin in patients with grade 2 HR (24.8 +/- 15.8 ng/mL; n = 22) was significantly higher than that in patients with grade 1 HR (16.1 +/- 4.9 ng/mL; n = 29; P = 0.001), grade 0 HR (5.1 +/- 3.1 ng/mL; n = 60; P = 0.001), and NT (P = 0.001). Plasma leptin in patients with grade 1 HR was also significantly higher than that in patients without retinopathy (P = 0.001) or in NT (P = 0.001). The estimated threshold of plasma leptin concentration for HR was 10.2 ng/mL. This critical leptin level served largely to separate patients with retinopathy from those without retinopathy. In summary, our results show that plasma leptin concentrations increase progressively with higher grades of hypertensive retinopathy even after correction for BMI, suggesting that a critical leptin level is needed for the development of retinopathy. Elevated concentrations of plasma leptin might be secondary to release of leptin by the vascular endothelium damaged by high blood pressure, as an epiphenomenon. However, a pathogenic role for leptin in hypertensive retinopathy cannot be excluded.
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Prediabetes has been associated with an increased risk of cardiovascular disease and mortality. Soluble P-selectin (sP-selectin) is an index of platelet activation and also a risk factor for future vascular events. sP-selectin levels were... more
Prediabetes has been associated with an increased risk of cardiovascular disease and mortality. Soluble P-selectin (sP-selectin) is an index of platelet activation and also a risk factor for future vascular events. sP-selectin levels were investigated in prediabetic subjects who had no confounding factors such as hypertension, obesity or dyslipidaemia. sP-selectin, hsCRP levels and HOMA-IR indexes were measured in 40 prediabetic subjects (n = 24 for IFG and n = 16 for IGT) and age-, sex- and BMI-matched 40 healthy controls. sP-selectin levels in prediabetic subjects were not significantly different compared with those in controls (p = 0.12). Prediabetic group had similar hsCRP (p = 0.29), higher HOMA-IR indexes (p < 0.001) and lower HDL cholesterol levels (p = 0.001) when compared with healthy controls. The power of the study was 0.93 for sP-selectin, 0.7 for hsCRP and 1.0 for HOMA. Our data suggest that sP-selectin may not contribute to the prothrombotic state as well as the accelerated atherogenesis associated with prediabetes.
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Previous studies demonstrated elevated plasma leptin and angiotensinogen (PRA) levels in essential hypertension. However, a few studies investigated the relationship between leptin and angiotensinogen levels in both lean and overweight/... more
Previous studies demonstrated elevated plasma leptin and angiotensinogen (PRA) levels in essential hypertension. However, a few studies investigated the relationship between leptin and angiotensinogen levels in both lean and overweight/ obese hypertensives. The aim of the present study was therefore to examine the relationship between blood pressure, leptin and plasma renin activity in normotensives and in both lean and overweight/obese patients with essential hypertension. Two groups of subjects who were carefully matched for age, gender, waist:hip ratio and body mass index (BMI) were studied: 28 normotensives (NT) (age: 40.1+/-9.1 years old, BMI: 28.1+/-3.6 kg/m2, male/female: 18/10) and 33 newly diagnosed mild to moderate essential hypertensives (EHT) (age: 38.9+/-10 years old, BMI: 27.9+/-4.8 kg/m2, male/female: 22/11). No significant differences in age, gender, waist:hip ratio, fasting blood glucose and BMI were detected between EHT and NT groups. However, systolic and diastolic pressures, mean arterial blood pressures, plasma leptin levels and PRA were significantly higher in EHT group than in NT group (P = 0.001). Plasma leptin levels were strongly correlated with BMI in EHT (r=0.67, P = 0.001) and NT groups (r=0.44, P = 0.001). Plasma leptin levels were correlated with plasma PRA levels in both EHT and NT groups (r = 0.66 and r = 0.44; both P < 0.05, respectively). There was no correlation between leptin or PRA and systolic, diastolic pressures, or mean arterial blood pressures. Furthermore, the patients were divided as lean (n=16) and overweight/obese (n = 17) and compared with BMI-matched controls. In both subgroups, plasma leptin and PRA levels were also higher than those of controls. Our results showed that elevated plasma leptin and PRA are associated with hypertension in both lean and overweight/obese hypertensives. Moreover, plasma leptin was significantly correlated with plasma angiotensinogen levels. These findings suggest that adipose mass is an important determinant of blood pressure, although the mechanism is not clear.