Gultekin Genctoy

Mersin University, Mercin, Mersin, Turkey

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Publications (14)21.03 Total impact

  • Article: Pulmonary hypertension in hemodialysis patients without arteriovenous fistula: the effect of dialyzer composition.
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    ABSTRACT: Pulmonary hypertension (PHT) increases mortality rate in hemodialysis (HD) patients. Numerous clinical, hemodynamic, and metabolic abnormalities have been suggested to be associated with the development of PHT in HD patients. We aimed to investigate the acute effects of two different dialyzer membranes on pulmonary arterial pressure (PAP) throughout a HD session in maintenance HD patients. Seventy-four HD patients dialyzed through permanent tunneled jugular central venous catheter were enrolled. A first-use cellulose acetate and high-flux polysulfone dialysis membrane were tested using a crossover design. For each membrane, pre- and post-dialysis pulmonary artery pressures were measured echocardiographically. Elevated pulmonary artery pressure was observed in 68.8% of patients (n = 51), whereas mild PHT was observed in 28.3% of patients (n = 21) and moderate PHT in 40.5% (n = 30). Decrease in pulmonary artery pressure following HD procedure performed using high-flux polysulfone membrane was significantly higher than the decrease observed following HD procedure performed using cellulose acetate membrane (p < 0.05). Significant decrease in pulmonary artery pressures was observed only after HD procedures performed using high-flux polysulfone membrane (p < 0.05). Ultrafiltered volume was only significantly correlated with the decrease in pulmonary artery pressure observed after HD procedure performed through high-flux polysulfone membrane (β = 0.411, p < 0.05). PHT seems to be prevalent among HD patients even in the absence of AV fistula and abnormal cardiac functions. Membrane composition seems to be important, which may overwhelm the improving effects of ultrafiltration.
    Renal Failure 01/2010; 32(10):1148-52. · 0.82 Impact Factor
  • Article: Serum stem cell factor level in renal transplant recipients with posttransplant erythrocytosis.
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    ABSTRACT: The etiology of posttransplant erythrocytosis (PTE) remains unclear, and the most frequently suggested causative factors are still a matter of controversy. We aimed to investigate serum-soluble stem cell factor (sSCF) along with serum erythropoietin (EPO) levels in renal transplant recipients (RTRs) with PTE. Thirteen RTRs with PTE, 42 RTRs without PTE, and 42 healthy controls were included. Serum sSCF and EPO levels were determined using an enzyme-linked immunosorbent assay kit. Expected and observed/expected EPO levels were calculated. Serum sSCF levels and observed/expected EPO were significantly higher in RTRs with PTE than both RTRs without PTE and controls. In RTRs with PTE, sSCF level was significantly correlated with hematocrit and observed/expected EPO, respectively. Significant correlation was also observed between hematocrit level and observed/expected EPO in RTRs with PTE. Increased sSCF level and inadequate suppression of EPO production seem to have a role in the pathogenesis of PTE.
    Artificial Organs 12/2009; 33(12):1086-90. · 2.00 Impact Factor
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    Article: Nephrotic-range proteinuria with small glomerular fibrillary deposits in a patient on diphenylhydantoin treatment.
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    ABSTRACT: Although the exact role of the diphenylhydantoin treatment on the immune system is still unclear, prolonged administration of diphenylhydantoin has been suggested to be associated with immune-based disorders and syndromes. A case of fibrillary glomerulonephritis associated with DPH treatment is reported. This is the first reported case of fibrillary glomerulonephritis associated with this commonly used common anticonvulsive drug. A more routine surveillance for proteinuria in patients receiving DPH is recommended.
    Medical science monitor: international medical journal of experimental and clinical research 09/2009; 15(8):CS132-4. · 1.70 Impact Factor
  • Article: The correlation of thrombolysis in myocardial infarction frame count with insulin resistance in patients with slow coronary flow.
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    ABSTRACT: It has been reported that coronary endothelial dysfunction plays an important pathogenetic role in patients with slow coronary flow (SCF). Insulin resistance is defined as impairment of insulin-stimulated glucose and/or lipid metabolism, while endothelial dysfunction is defined as paradoxical or inadequate endothelial-mediated vasodilation. In this study, we aimed to evaluate insulin resistance in patients with SCF. The study population included 25 patients with SCF and 28 healthy controls. Insulin resistance was estimated via homeostasis model assessment insulin resistance index (HOMA-IR). Patients with SCF had higher high-sensitive C-reactive protein (hs-CRP) and HOMA-IR scores (P<0.05) than controls. Mean thrombolysis in myocardial infarction frame count had significant correlation with hs-CRP, fasting plasma insulin levels and HOMA-IR score (r=0.566, P<0.05; r=0.883, P<0.05; r=0.884, P<0.05, respectively). In patients with SCF, thrombolysis in myocardial infarction frame counts and hs-CRP are correlated with increased insulin resistance and thus, it can be suggested that insulin resistance and inflammation may, in part, have a role in the pathogenesis of SCF.
    Coronary artery disease 01/2009; 19(8):591-5. · 1.56 Impact Factor
  • Article: The interleukin-10 promoter genotype predicts diastolic dysfunction in maintenance hemodialysis patients.
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    ABSTRACT: Interleukin-10 (IL-10) predominantly acts as an anti-inflammatory factor. Polymorphisms in the IL-10 gene promoter determine quantitative cytokine production. Doppler echocardiography and tissue Doppler imaging (TDI) are superior to conventional echocardiography to evaluate diastolic dysfunction. The IL-10 gene promoter polymorphism at position (-1082) was studied for its association with conventional and Doppler echocardiographic and TDI parameters in 112 hemodialysis (HD) patients. Blood pressure, serum C-reactive protein (CRP), and albumin levels were also examined for the association study. The genetic association study showed that among the HD patients, there was no difference in the prevalence of systolic and diastolic dysfunction between genotypes on conventional echocardiography. However, using Doppler echocardiography and TDI, high producers for the IL-10 -1082 promoter (-1082/GG) have higher E velocities, E/A values, lateral, and septal E' velocities and a lower isovolumic ventricular relaxation time than low (-1082/AA) and intermediate producers (-1082/GA). Significantly higher levels of serum CRP levels and lower plasma albumin levels were found in low and intermediate producers for the IL-10 -1082 promoter than high producers. The IL-10 genotype may balance the effects of inflammatory cytokines on the myocardium and may be a determinant of LV function in HD patients.
    Hemodialysis International 07/2008; 12(3):352-61. · 1.54 Impact Factor
  • Article: Crataegus orientalis associated multiorgan hypersensitivity reaction and acute renal failure.
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    ABSTRACT: Patients, especially those with chronic disease and disorders are increasingly relying on complementary and alternative medical therapies (CAMT). Because the use of CAMT is escalating worldwide, it is essential to be aware of the clinical and adverse effects, doses and potential drug-herb interactions. Crataegus orientalis or hawthorn is a small tree with red fruits. A number of studies appear to demonstrate that Crataegus spp. have a clinically detectable positive cardiac inotropic action. The ingredients, characteristics of metabolism and elimination, and adverse effects of hawthorn remain largely unknown. We report a case of multisystem hypersensitivity reaction and progressive acute renal failure associated with the consumption of Crataegus orientalis.
    Internal Medicine 02/2008; 47(23):2039-42. · 0.94 Impact Factor
  • Article: The influence of hemodialysis on P-wave signal-averaged electrocardiogram findings.
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    ABSTRACT: The role of P-wave signal-averaged electrocardiography (P-SAECG) in the prediction of atrial fibrillation (AF) attacks has been validated in various disease states. In the present study, we aimed to investigate the effect of hemodialysis (HD) on P-SAECG parameters and to determine the related risk factors that might affect those parameters. Ninety-one HD patients and 68 controls were included. Hemoglobin levels, serum electrolytes, arterial pH, and interdialytic weight changes were assessed. P-wave duration (PWD) and late potentials of P wave (root-mean-square voltage for the last 20 ms of the signal-averaged P wave [LP20]) were determined by P-SAECG. Pre- and postdialysis PWDs were significantly increased in HD patients than in controls (both P < 0.05), while the voltages of pre- and postdialysis LP20 were significantly reduced (both P < 0.05). A significant increase in PWD (P < 0.05) and a significant decrease in LP20 (P < 0.05) were observed following HD. Pre- and postdialysis PWDs and LP20 were correlated with age (all P < 0.05), dialysis duration (all P < 0.05), and left atrial diameters (LADs) (pre- and postdialysis) (all P < 0.05). Intradialytic changes in serum potassium levels were only correlated with postdialysis PWD and LP20 in HD patients (both P < 0.05). HD seems to increase PWD and to reduce LP20. Advanced age, duration of HD, intradialytic change in serum potassium levels, and LAD seem to be the important associates of P-SAECG parameters in HD patients.
    Artificial Organs 09/2007; 31(8):612-6. · 2.00 Impact Factor
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    Article: The prevalance, epidemiology and risk factors for onychomycosis in hemodialysis patients.
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    ABSTRACT: Onychomycosis has a high prevalance among immunocompromised patients such as diabetics and hemodialysis patients. In the present study, we aimed to investigate the prevalence of onychomycosis among hemodialysis patients with and without diabetes mellitus, and to find out the factors likely to be associated with the development of onychomycosis among hemodialysis patients. One hundred and nine hemodialysis patients were enrolled. Fifty-seven of hemodialysis patients had the diagnosis of diabetes mellitus. Nail scrapings were obtained from 76 patients who had dystrophic nail changes. Samples were examined with 20% potassium hydroxide solution and all of the samples were inoculated on Saboraud's dextrose agar, potateus dextrose agar and mycobiotic agar. Diagnosis of onychomycosis was based on the presence of both positive clinical signs and positive potassium hydroxide test. Onychomycosis was diagnosed in 26.6% of hemodialysis patients. Diabetes mellitus was present in 68.9% of patients with onychomycosis. Toenail scraping cultures were reported to be positive in 19.7% of patients with dystrophic nail changes. Logistic regression analysis revealed that the presence of diabetes mellitus and the mean duration of hemodialysis were the significant predictors associated with the development of onychomycosis. The prevalence of dystrophic nail changes and onychomycosis is increased among hemodialysis patients. The dialysis duration and the presence of diabetes mellitus are the independent risk factors associated with the development of onychomycosis in uraemic patients.
    BMC Infectious Diseases 02/2007; 7:102. · 3.12 Impact Factor
  • Article: Impact of rHuEPO therapy initiation on soluble adhesion molecule levels in haemodialysis patients.
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    ABSTRACT: Increased levels of soluble adhesion molecules have been reported in haemodialysis (HD) patients. Recent studies have shown that recombinant human erythropoietin (rHuEPO) elicits proliferation and migration of endothelial cells and modifies endothelial function. The present study was design to explore the effects of rHuEPO on serum levels of soluble adhesion molecules in HD patients. Soluble serum levels of E-selectin (sE-selectin), intracellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) were measured by ELISA in 29 rHuEPO naïve HD patients (20 males, 9 females) and 10 control subjects at baseline and second month. The HD patients with a haemoglobin level lower than 10.0 mg/dL (n = 19) were administered rHuEPO therapy and other HD patients (n = 10) were followed as a placebo group. Serum levels of soluble adhesion molecules were significantly higher in HD patients compared with the control group. A significant rise from the baseline in sE-selectin levels (77 +/- 70 vs 100 +/- 86 ng/mL, P < 0.05) was observed 2 months after rHuEPO initiation, while sICAM-1 and sVCAM-1 levels decreased (271 +/- 261 vs 197 +/- 89 and 1043 +/- 243 vs 990 +/- 236 ng/mL, respectively, P < 0.05). The present data indicate that rHuEPO could have an important action on serum levels of soluble adhesion molecules in HD patients. rHuEPO might modify the expression of adhesion molecules from endothelial cells either. However, the exact mechanism responsible for the serum elevation of these molecules in HD patients is yet to be fully elucidated.
    Nephrology 06/2005; 10(3):264-9. · 1.31 Impact Factor
  • Article: TNF alpha-308 genotype and renin-angiotensin system in hemodialysis patients: an effect on inflammatory cytokine levels?
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    ABSTRACT: Renin-angiotensin system (RAS) was suggested to modulate inflammatory cytokine production. Angiotensin II was consistently shown to increase production of tumor necrosis factor alpha (TNF-alpha). However, inflammatory cytokines and RAS were modulated by genetic polymorphisms such as TNF-alpha-308 G > A and angiotensin-converting enzyme (ACE) I/D gene polymorphisms. The aim of this study was to investigate the effects of ACE and TNF-alpha genotypes on inflammatory cytokines in hemodialysis (HD) patients. ACE I/D and TNF-alpha-308 G > A genotypes, pre- and postdialysis plasma renin activity (PRA), serum ACE, interleukin-1 beta (IL-1beta), and TNF-alpha levels were determined in 22 HD patients. Predialysis serum ACE activity is correlated with TNF-alpha (r = 0.63; P = 0.01), and PRA was correlated with IL-1beta levels (r = 0.49; P = 0.02). Pre/postdialysis IL-1beta and TNF-alpha were similar in DD and II/ID ACE genotypes. Predialysis TNF-alpha and IL-1beta (32.4 +/- 5; 35.1 +/- 4.2 vs. 28.1 +/- 3.7; 26.5 +/- 6.2 pg/mL; P < 0.05) and postdialysis TNF-alpha levels (30.4 +/- 1.4 vs. 28.4 +/- 0.82 pg/mL; P < 0.05) were significantly higher in TNF1/2 than TNF1/1 patients. ACE and TNF-alpha-308 G > A (1/2) gene polymorphisms may contribute to modulation of proinflammatory cytokine production and hence chronic inflammation in HD patients.
    Artificial Organs 03/2005; 29(2):174-8. · 2.00 Impact Factor
  • Article: Efficacy and safety of intravenous iron therapy for HCV-positive haemodialysis patients.
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    ABSTRACT: Iron supplementation is the cornerstone of anaemia management in haemodialysis (HD) patients. However, efficacy and safety of intravenous (IV) iron therapy in hepatitis C virus (HCV)-positive HD patients is yet to be elucidated. Sixty-six maintenance HD patients with suboptimal response to recombinant human erythropoietin (rh-EPO) were administered IV iron. Each patient received 100 mg/session IV iron sucrose for ten consecutive HD sessions and then the dose was decreased to 50-100 mg weekly or biweekly. Patients were followed for haemoglobin (Hb), ferritin, rh-EPO dose requirements, transaminase levels, and adverse drug reactions. Baseline demographic and clinical characteristics, as well as Hb, ferritin, transaminase levels, rh-EPO and iron doses were similar between HCV-positive (n = 32) and HCV-negative patients (n = 29). After 5 months of follow-up, a significant increase in ferritin and Hb levels and decrease in rh-EPO doses were observed in both groups. The incidence of adverse drug reactions was not associated with HCV serology. Significant elevation in both alanine and aspartate aminotransferase levels were detected in HCV-positive patients. This study has shown that IV iron administration reverses suboptimal response to rh-EPO administration in HD patients regardless of HCV serology. There is however subtle increase of transaminase levels in HCV-positive patients. Further studies are warranted to reveal the impact of variation in serum transaminase levels during IV iron administration in HCV-positive HD patients.
    Nephron Clinical Practice 02/2005; 100(3):c78-85. · 2.04 Impact Factor
  • Article: TNF Alpha−308 Genotype and Renin–Angiotensin System in Hemodialysis Patients: An Effect on Inflammatory Cytokine Levels?
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    ABSTRACT:   Background: Renin–angiotensin system (RAS) was suggested to modulate inflammatory cytokine production. Angiotensin II was consistently shown to increase production of tumor necrosis factor alpha (TNF-α). However, inflammatory cytokines and RAS were modulated by genetic polymorphisms such as TNF-α−308 G > A and angiotensin-converting enzyme (ACE) I/D gene polymorphisms. The aim of this study was to investigate the effects of ACE and TNF-α genotypes on inflammatory cytokines in hemodialysis (HD) patients. Methods: ACE I/D and TNF-α−308 G > A genotypes, pre- and postdialysis plasma renin activity (PRA), serum ACE, interleukin-1 beta (IL-1β), and TNF-α levels were determined in 22 HD patients. Results: Predialysis serum ACE activity is correlated with TNF-α (r = 0.63; P = 0.01), and PRA was correlated with IL-1β levels (r = 0.49; P = 0.02). Pre/postdialysis IL-1β and TNF-α were similar in DD and II/ID ACE genotypes. Predialysis TNF-α and IL-1β (32.4 ± 5; 35.1 ± 4.2 vs. 28.1 ± 3.7; 26.5 ± 6.2 pg/mL; P < 0.05) and postdialysis TNF-α levels (30.4 ± 1.4 vs. 28.4 ± 0.82 pg/mL; P < 0.05) were significantly higher in TNF1/2 than TNF1/1 patients. Conclusion: ACE and TNF-α−308 G > A (1/2) gene polymorphisms may contribute to modulation of proinflammatory cytokine production and hence chronic inflammation in HD patients.
    Artificial Organs 01/2005; 29(2):174 - 178. · 2.00 Impact Factor
  • Article: P-432: Metabolic determinants of pulse pressure in hemodialysis patients
  • Article: P-433: An inflation of diagnostic tests in young hypertensive patients: a need for diagnostic guideline?