Person: YAVUZ, DİLEK
Loading...
Email Address
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
YAVUZ
First Name
DİLEK
Name
35 results
Search Results
Now showing 1 - 10 of 35
Publication Metadata only Peripheral nervous system assessment in acromegaly patients under somatostatin analogue therapy(SPRINGER, 2017) YAVUZ, DİLEK; Alibas, H.; Yavuz, D. Gogas; Koytak, P. Kahraman; Uygur, M.; Tanridag, T.; Uluc, K.Purpose Acromegaly is known to affect peripheral nervous system (PNS) causing carpal tunnel syndrome (CTS) and polyneuropathy. The frequency of these disorders and the evaluation methods vary among studies. In the present study, we aimed to examine PNS of acromegaly patients under somatostatin analogue (SSA) therapy. Methods Forty-eight acromegaly patients (26 F/22 M, 45.58 +/- 11.6 years) under SSA treatment and 44 healthy controls (25 F/19 M, 47.46 +/- 8.7 years) were assessed by symptom questionnaires, neurologic examination and electrophysiological studies. Results 87.5 % of the acromegaly patients had at least one abnormal finding regarding PNS. With the incorporation of palm-wrist median nerve conduction velocity method, we detected CTS in 50 % of patients. Polyneuropathy was less frequent (29.2 %). Both conditions were independent from the coexisting diabetes mellitus (p = 0.22 for CTS, p = 0.71 for polyneuropathy). Polyneuropathy but not CTS was more common among biochemically uncontrolled acromegaly patients rather than those under control (p = 0.03; p = 0.68, respectively). Conculsion Our findings emphasize the high prevalence of peripheral nervous system involvement in acromegaly patients under SSA therapy and importance of neurological evaluation of these patients. Early diagnosis and treatment of the disease may reduce the PNS involvement.Publication Metadata only Estrogen receptor gene polymorphisms in a group of postmenopausal Turkish women: association with bone mineral density(TAYLOR & FRANCIS LTD, 2012) YOLDEMİR, AHMET TEVFİK; Yavuz, D. G.; Yoldemir, T.; Ozaltun, K.; Erenus, M.Objective To evaluate the frequency of the estrogen receptor (ER) gene PvuII and XbaI polymorphisms and their associations with bone mineral density (BMD) in a group of postmenopausal Turkish women. Design A total of 125 healthy postmenopausal women and 125 premenopausal healthy young women as controls were included in the study. The PvuII and XbaI polymorphisms in the ER gene were studied by the polymerase chain reaction-restriction fragment length polymorphism method. The BMD of the lumbar vertebrae and femoral neck were measured by dual-energy X-ray absorptiometry. Results The frequencies of the ER alpha PVuII genotypes PP, Pp and pp were 20%, 54.4% and 25.6% in premenopausal and 24.8%, 44.8% and 30.4% in postmenopausal women, respectively. The frequencies of the ER XbaI genotypes XX, Xx, xx were 16.8%, 48.8% and 34.4% in premenopausal and 16.8%, 48% and 35.2% in postmenopausal women, respectively. There was no difference in the frequencies of ER gene polymorphisms between premenopausal and postmenopausal women. BMD measurements were not different between ER PvuII and XbaI genotypes in premenopausal and postmenopausal women. Conclusions ER gene PvuII and XbaI polymorphisms have no major influence on bone mineral density in our group of postmenopausal women.Publication Metadata only Vitamin D receptor gene BsmI, FokI, ApaI, TaqI polymorphisms and bone mineral density in a group of Turkish type 1 diabetic patients(SPRINGER-VERLAG ITALIA SRL, 2011) YAVUZ, DİLEK; Yavuz, Dilek Gogas; Keskin, Lezan; Kiyici, Sinem; Sert, Murat; Yazici, Dilek; Sahin, Ibrahim; Yuksel, Meral; Deyneli, Oguzhan; Aydin, Hasan; Tuncel, Ercan; Akalin, SemaPrevious studies have suggested an influence of vitamin D receptor alleles on bone metabolism and on susceptibility to type 1 diabetes mellitus in different ethnic populations. We aimed to investigate the distribution of vitamin D receptor (VDR) alleles in relation to biochemical bone turnover parameters and bone densitometry measurements in a group of Turkish type 1 diabetic patients. One hundred and seventeen patients (M/F 57/60, 27.6 +/- A 7.3 y duration of diabetes 8.1 +/- A 6.3 y) and 134 healthy controls (M/F 61/73, 26.2 +/- A 5.3 y) were included in the study. Bone mineral density (BMD) was evaluated by dual-energy X-ray absorptiometry (DEXA). The vitamin D receptor gene (VDR) polymorphisms FokI, Bsm1, Apa1, and Taq1 were examined using a PCR-based restriction analysis. Serum levels of calcium, phosphor osteocalcin, intact parathyroid hormone, and C telopeptide were measured. Vitamin D receptor Bsm1 Fok1, Apa1, and Taq1 genotype distributions were not different between patient with diabetes and control groups. BMD was 0.77 +/- A 0.2 g/cm(2) vs. 0.97 +/- A 0.2 g/cm(2) (P = 0.0001) for the femur, 1.0 +/- A 0.1 g/cm(2) vs. 1.13 +/- A 0.1 g/cm(2) (P = 0.001) for type 1 diabetic patients and controls. Bone turnover markers were significantly lower in type 1 diabetic group. BMD measurements and bone metabolic markers were not different between the genotypes in either the patient with diabetes or the controls. The VDR gene polymorphisms, Bsm1, Fok 1, Apa1, and Taq1 showed no influence on bone metabolism in our group of type 1 diabetic patients.Publication Metadata only Epicardial Fat Tissue Thickness Correlates with Endothelial Dysfunction and Other Cardiovascular Risk Factors in Patients with Metabolic Syndrome(MARY ANN LIEBERT, INC, 2010) YAVUZ, DİLEK; Aydin, Hasan; Toprak, Ahmet; Deyneli, Oguzhan; Yazici, Dilek; Tarcin, Oezlem; Sancak, Seda; Yavuz, Dilek; Akalin, SemaBackground: Epicardial adipose tissue has shown to be related to cardiovascular risk. The aim of this study is to investigate the relationship between epicardial adiposity and endothelial function in metabolic syndrome. Methods: Fifty patients with metabolic syndrome were recruited. Anthropometric measurements, fasting blood glucose, insulin, lipid profile, high-sensitivity C-reactive protein (hsCRP), fibrinogen, apolipoprotein A (Apo A), Apo B1, and lipoprotein (a) [Lp(a)] were determined. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Epicardial fat thickness was measured via two-dimensional M-mode echocardiography. Endothelial function was assessed as flow-mediated dilatation at the brachial artery. Results: Epicardial fat tissue thickness was shown to be correlated negatively with FMD and positively with age, diastolic blood pressure, hsCRP, fibrinogen, HOMA-IR, and lipid parameters. Multiple regression analysis showed epicardial fat tissue thickness to be an independent factor influencing the endothelial function. Conclusions: Epicardial fat tissue may be a useful parameter in the assessment of patients with metabolic syndrome.Publication Metadata only Vitamin D receptor gene polymorphisms in a group of postmenopausal Turkish women: association with bone mineral density(INFORMA HEALTHCARE, 2011) YOLDEMİR, AHMET TEVFİK; Yoldemir, T.; Yavuz, D. G.; Anik, G.; Verimli, N.; Erenus, M.Objective To determine the frequency of the vitamin D receptor (VDR) gene polymorphisms BsmI, ApaI, TaqI and FokI and their associations with bone mineral density (BMD) in postmenopausal Turkish women. Design One hundred and thirty healthy postmenopausal women and 130 premenopausal healthy women acting as controls were included in the study. The BsmI, FokI, ApaI and TaqI polymorphisms in the VDR gene were studied by polymerase chain reaction-restriction fragment length polymorphism method. The BMD of the lumbar vertebrae and femur neck were measured by dual-energy X-ray absorptiometry. Comparisons between the groups were performed using the paired t-test and ANOVA. chi(2) or contingency tables were used to analyze qualitative results. Results Genotypes BB, Bb and bb occurred in premenopausal women with frequencies of 16.92%, 50% and 33.08% and in postmenopausal women with frequencies of 16.92%, 56.15% and 26.92%, respectively. Genotypes FF, Ff, ff occurred in premenopausal women with frequencies of 47.69%, 42.31% and 10% and in postmenopausal women with frequencies of 50.77%, 42.31% and 6.92%, respectively. Genotypes AA, Aa, aa occurred in premenopausal women with frequencies of 23.85%, 56.15% and 20% and in postmenopausal women with frequencies of 26.15%, 46.15% and 27.70%, respectively. Genotypes TT, Tt and tt occurred in premenopausal women with frequencies of 37.69%, 45.38% and 16.92% and in postmenopausal women with frequencies of 39.23%, 45% and 15.38%, respectively. There was no difference in the frequencies of VDR gene polymorphisms between premenopausal and postmenopausal women. BMD measurements were not different between genotypes in premenopausal and postmenopausal women. Conclusions The VDR gene BsmI, FokI, ApaI and TaqI polymorphisms have no major influence on bone mineral density in our group of postmenopausal women.Publication Metadata only Effects of restoration of the euthyroid state on epicardial adipose tissue and carotid intima media thickness in subclinical hypothyroid patients(HUMANA PRESS INC, 2015) ÖZBEN SADIÇ, BESTE; Yazici, Dilek; Ozben, Beste; Toprak, Ahmet; Yavuz, Dilek; Aydin, Hasan; Tarcin, Ozlem; Deyneli, Oguzhan; Akalin, SemaEpicardial adipose tissue (EAT) thickness is a novel cardiovascular risk indicator, whereas carotid intima media thickness (CIMT) is a known marker of subclinical atherosclerosis. The aim of this study was to measure EAT thickness and CIMT in subclinical hypothyroid (SCH) patients and to determine the effect of restoration of the euthyroid state on these variables. The study included 43 patients with SCH (mean age: 35.2 +/- 10.7 years; F-M ratio: 42: 1) and 30 healthy controls (mean age: 34.5 +/- 8.2 years; F-M ratio: 25: 5). EAT thickness and CIMT were measured via conventional echocardiography and ultrasonography. Among the patients, 23 were followed up with L-thyroxine replacement until restoration of the euthyroid state and re-evaluated 6 months after baseline. Basal EAT thickness was higher in the SCH patients than in the controls (3.2 +/- 0.7 vs. 2.3 +/- 0.3 mm-p < 0.0001), whereas CIMT was similar in both groups (0.50 +/- 0.09 vs. 0.48 +/- 0.04 mm). EAT thickness was correlated with CIMT in the patient group (r = 0.39, p = 0.01), but this correlation was not evident based on multivariate analysis when corrected for age and body mass index (r(2) = 0.47 and p = 0.0001 for the model). In the follow-up patient subgroup, both EAT thickness and CIMT decreased significantly following L-thyroxine treatment, when normal TSH levels were attained (3.4 +/- 0.7 vs. 2.3 +/- 0.5 mm-p = 0.007 and 0.51 +/- 0.09 vs. 0.46 +/- 0.07 mm-p = 0.01, respectively). EAT thickness was greater in the SCH patients than in controls, whereas CIMT was similar in both groups. Restoration of the euthyroid state with L-thyroxine treatment was associated with significant decreases in EAT thickness and CIMT in the group of patients that received L-thyroxine treatment and, as such, might reduce the cardiovascular risk associated with SCH.Publication Metadata only Effects of vitamin D supplementation on insulin sensitivity and androgen levels in vitamin-D-deficient polycystic ovary syndrome patients(WILEY, 2018) YOLDEMİR, AHMET TEVFİK; Karadag, Cihan; Yoldemir, Tevfik; Yavuz, Dilek GogasAimThe aim of this study was to identify the effects of vitamin D supplementation on insulin sensitivity and androgen levels in vitamin-D-deficient polycystic ovary syndrome (PCOS) patients. MethodsSixty-seven vitamin-D-deficient (25-hydroxyvitamin D [25(OH)D] levels below 20ng/mL) PCOS patients and 54 vitamin-D-deficient non-PCOS volunteer subjects matched for age and body mass index were enrolled to this prospective study. All participants were given 50000IU/week cholecalciferol orally for 8weeks and 1500IU/day for 4weeks. Insulin sensitivity was calculated with the Matsuda insulin sensitivity index (ISI) based on an oral glucose tolerance test. Matsuda ISI, gonadal hormones (estrogen, testosterone, androstenedione), and 25(OH)D levels were studied before and at the end of the 12th week of vitamin D load. ResultsAfter vitamin D supplementation, serum androstenedione levels had decreased significantly (P=0.007) and Matsuda ISI values had increased significantly (P=0.001) in the PCOS group but no significant changes were seen in those parameters in controls. We observed positive correlations between 25(OH)D levels and Matsuda ISI (r=0.307; P< 0.01), and negative correlations between 25(OH)D levels and total testosterone (r=-0.306; P< 0.01) and androstenedione (r=-0.275; P< 0.01) levels in the PCOS group. ConclusionVitamin D supplementation increased insulin sensitivity and decreased androgen levels in vitamin-D-deficient women with PCOS but did not have any effect in vitamin-D-deficient non-PCOS women. These results may indicate the possible role of vitamin D in the complex pathogenesis of PCOS.Publication Metadata only The association of osteopenia with levels of serum 25-hydroxyvitamin D and HOMA-IR values(TAYLOR & FRANCIS LTD, 2014) YOLDEMİR, AHMET TEVFİK; Yoldemir, T.; Yavuz, D. G.Objective To determine the association of osteopenia with levels of serum 25-hydroxyvitamin D and HOMA-IR values in postmenopausal women. Methods One hundred healthy postmenopausal women were included in a cross-sectional study. Venous blood was collected after an overnight fast and 25-hydroxyvitamin D, glucose and insulin levels were measured. HOMA-IR was calculated. Bone mineral density was measured with a dual X-ray absorptiometer. Results There was no difference in serum 25-hydroxyvitamin D levels and HOMA-IR values between the two groups. A weak positive correlation between serum 25-hydroxyvitamin D levels and osteopenia was detected. Insulin resistance had a weak negative association with osteopenia. Conclusions The correlations between osteopenia and serum 25-hydroxyvitamin D levels and HOMA-IR values were weak among early postmenopausal women.Publication Metadata only Epicardial adipose tissue thickness in type 1 diabetic patients(SPRINGER, 2011) ÖZBEN SADIÇ, BESTE; Yazici, Dilek; Ozben, Beste; Yavuz, Dilek; Deyneli, Oguzhan; Aydin, Hasan; Tarcin, Ozlem; Akalin, SemaInsulin resistance is getting important in the course of type 1 diabetes mellitus. Visceral fat depot is associated with insulin resistance and assessment of epicardial fat thickness is a way of measuring visceral fat. The aim of the study was to measure epicardial adipose tissue (EAT) thickness and to determine its relationship with waist-hip-ratio (WHR) and estimated glucose disposal rate (eGDR) in adult type 1 diabetic patients. Thirty-six type 1 diabetic patients (aged 31 +/- 8 years; Female/Male: 22/14) and 43 age, gender and BMI matched healthy controls were included. Fasting blood glucose (FBG), hemoglobin A1c, and lipid profiles were measured. Waist-hip-ratio (WHR) was calculated. Daily insulin dose/kg of patients were recorded and eGDR of all subjects was calculated. Epicardial adipose tissue (EAT) thickness was evaluated by echocardiography. EAT thickness of the type 1 diabetic patients was significantly higher than controls (3.30 +/- 1.06 vs. 2.30 +/- 0.34 mm, P < 0.0001). EAT thickness was correlated with age (P = 0.05; r = 0.35), WHR (P = 0.003; r = 0.67), daily insulin dose/kg (r = 0.45, P = 0.005), and eGDR (r = -0.55, P = 0.0004). Multivariate analysis revealed WHR and eGDR to be related to EAT among age, WHR, daily insulin dose/kg, eGDR, FBG, and hemoglobin A1c (r(2) of the model = 0.64). Epicardial adipose tissue thickness is increased in type 1 diabetic patients compared to controls and is related to WHR and eGDR in this group of patients. This measurement may point to the presence of insulin resistance in type 1 diabetic patients.Publication Metadata only Increased serum sialic acid in diabetic retinopathy of type 1 diabetes(2013) YAVUZ, DİLEK; Eraslan M., Yenice O., Kazokoglu H., Yavuz D.G., Cerman E., Celiker H.AIM: To investigate the potential association between serum sialic acid and diabetic retinopathy and its several grades. METHODS: We studied the level of serum sialic acid in 70 patients. Thirty control vs 40 type 1 diabetics and with different levels of diabetic retinopathy as well. RESULTS: We found higher levels of serum sialic acid level in diabetics compared to control subjects (95.95±9.5 vs 45.05±19.91 mmoL/L, P=0.0001). We also observed a progressive rise in its concentration as the level of diabetic retinopathy increased (P<0.05) but the correlation was weak. Serum sialic acid level correlated positively with blood glucose level (r=0.67, P=0.0001). CONCLUSION: Increase in serum sialic acid levels seems to be related to the stage of the retinopathy and may help us to determine the extent of retinopathy in type 1 diabetic patients. But we think that we need more detailed studies to get a more precise conclusion.