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Dive into the research topics where Gursel Biberoglu is active.

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Featured researches published by Gursel Biberoglu.


Clinical Endocrinology | 2007

Serum leptin, oxidized low density lipoprotein and plasma asymmetric dimethylarginine levels and their relationship with dyslipidaemia in adolescent girls with polycystic ovary syndrome

Fatma Demirel; Aysun Bideci; Peyami Cinaz; M. Orhun Çamurdan; Gursel Biberoglu; Ediz Yesilkaya; Alev Hasanoglu

Objective  The aim of this study was to investigate serum leptin, oxidized low density lipoprotein (ox‐LDL) and asymmetric dimethylarginine (ADMA) levels and their interaction with dyslipidaemia in adolescents with polycystic ovary syndrome (PCOS).


Acta Cardiologica | 2008

Asymmetrical dimethylarginine level in atrial fibrillation

Atiye Çengel; Asife Sahinarslan; Gursel Biberoglu; Alev Hasanoglu; Yusuf Tavil; Murat Tulmac; Murat Özdemir

Objective — Atrial fibrillation (AF) is known to be related with increased risk of thromboembolic events. Asymmetrical dimethylarginine (ADMA), which is an endogenous inhibitor of nitric oxide synthase (NOS), can cause endothelial dysfunction by decreasing nitric oxide (NO) and lead to increased risk of thrombosis. In the present study our aim was to compare plasma levels of ADMA in patients with acute onset (< 24 hours) and chronic AF (> 1 year) to determine the risk of thrombosis. Method — 17 patients with the first detected attack of AF within the first 24 hours of presentation (group I), 25 patients who had permanent chronic AF lasting at least 1 year or more (group II) and 18 healthy persons as the control group (group III) were included in the study. For each patient the plasma ADMA, L-arginine, symmetrical dimethylarginine (SDMA) concentrations were measured by high-performance liquid chromatography in venous blood samples collected before cardioversion. We compared the plasma ADMA, L-arginine and SDMA concentrations between the groups. Results — Plasma L-arginine (78.18 ± 28.29 vs. 73.14 ± 14.11 vs. 71.03 ± 21.31, P = 0.549) and plasma SDMA concentrations (0.38 ± 0.18 vs. 0.42 ± 0.21 vs. 0.32 ± 0.24, P = 0.224) were similar in all groups. There was a significant difference between plasma ADMA concentrations (0.76 ± 0.27 vs. 0.50 ± 0.26 vs. 0.36 ± 0.20, P < 0.001) among the groups.When we compared plasma ADMA levels between the subgroups, we also found a significant difference (P = 0.002 when comparing group I and group II, P < 0.001 when comparing of group I and group III, P = 0.042 when compareng of group II and group III). Conclusion — ADMA levels in patients with acute onset AF were significantly increased when compared with patients with chronic AF and the healthy control group indicating the presence of endothelial dysfunction and a prothrombotic state even in a very early phase of AF.


Clinical Neurology and Neurosurgery | 1999

Excitatory amino acids and taurine levels in cerebrospinal fluid of hypoxic ischemic encephalopathy in newborn

Yıldız Atalay; Yusuf Ziya Aral; Alev Hasanoglu; Canan Turkyilmaz; Gursel Biberoglu

The recent studies indicating the transiently enhanced expression of excitatory amino acid receptors in hypoxia vulnerable brain regions and the elevated concentration of aspartate and glutamate in cerebrospinal fluid of asphyxiated newborns strongly suggest the role of excitatory amino acids in hypoxic ischemic brain damage in the developing human brain. In this study, we compared the concentrations of glutamate, aspartate, taurine and glycine in the cerebrospinal fluid of asphyxiated infants with values of a healthy control group. The concentrations of aspartate (5.82 +/- 3.36), glutamate (1.76 +/- 1.0) and taurine (9.32 +/- 9.1) were significantly elevated in cerebrospinal fluid of asphyxiated infants (P < 0.05). When compared to the control group, the high levels of aspartate was correlated with the degrees of hypoxic-ischemic encephalopathy (HIE) and the varying outcome. The high levels of aspartate and glutamate in the asphyxiated patients adds further evidence to the role of excitotoxicity in hypoxic ischemic encephalopathy. The mental and motor development of the patients in asphyxiated group was followed for 3 years.


European Journal of Pediatrics | 2011

N-carbamylglutamate treatment for acute neonatal hyperammonemia in isovaleric acidemia

Çiğdem Seher Kasapkara; Fatih Süheyl Ezgü; Ilyas Okur; Leyla Tümer; Gursel Biberoglu; Alev Hasanoglu

Hyperammonemia occurs mainly in patients with branched-chain organic acidemias such as propionic, methylmalonic, and isovaleric acidemias. Its pathophysiological process is mainly via the competitive inhibition of N-acetylglutamate synthetase. Oral carglumic acid (N-carbamylglutamate) administration can correct hyperammonemia in neonates with propionic and methylmalonic acidemias, thus avoiding dialysis therapy. Isovaleric acidemia is an autosomal recessive disease of leucine metabolism due to deficiency of isovaleryl-CoA dehydrogenase. For the first time, we report a neonate with isovaleric acidemia, whose plasma ammonia concentration dropped dramatically after one oral load of carglumic acid. This experience suggests that carglumic acid could be considered for acute hyperammonemia resulting from isovaleric acidemia. However, trials with more patients are needed.


Journal of Child Neurology | 2009

3-Methylcrotonyl-CoA carboxylase deficiency: phenotypic variability in a family.

F. Tuba Eminoglu; Aysima Özçelik; Ilyas Okur; Leyla Tümer; Gursel Biberoglu; Ercan Demir; Alev Hasanoglu; Matthias R. Baumgartner

A family with 3-methylcrotonyl-CoA carboxylase deficiency with different clinical features is described. A 15-month-old boy, who was the index patient, was admitted to the hospital with atonic seizure. His brother had delayed language development and their uncle had been followed with diagnosis of epilepsy for the last 5 years. Urinary organic acid analysis displayed elevated 3-hydroxyisovaleric acid and 3-methylcrotonylglycine, analysis of acylcarnitines showed elevated 3-hydroxyisovalerylcarnitine and decreased free carnitine levels in both the patients and their uncle. Methylcrotonyl-CoA carboxylase activity in cultured fibroblasts displayed a low residual activity of 2.2% of the median control value while propionyl-CoA carboxylase activity was normal in the index patient. Mutation analysis revealed a large homozygous deletion of 2264 bp (c.873+4524_6787de12264) in the MCCA gene, which has not been described to date. Adult-onset afebrile seizures have not been reported in the literature. Our cases are an example of this wide phenotypic variability within a single family.


Coronary Artery Disease | 2008

Asymmetric dimethylarginine and coronary collateral vessel development.

Sinan Altan Kocaman; Asife Sahinarslan; Gursel Biberoglu; Alev Hasanoglu; Ahmet Akyel; Timur Timurkaynak; Atiye Çengel

IntroductionNitric oxide (NO) plays a major role in collateral vessel development. Asymmetric dimethylarginine (ADMA) that is an endogenous inhibitor of NO synthesis may impair the effective coronary collateral vessel development. The aim of this study was to evaluate the relationship between plasma ADMA level and coronary collateral vessel development. MethodsThe patients with a greater than or equal to 95% obstruction in at least one epicardial coronary artery were included in the study. Degree of coronary collateral development was determined according to Rentrop method. Patients with grade 2–3 collateral development were regarded as good collateral group and formed group I. The patients with grade 0–1 collateral development were regarded as poor collateral group and were included in group II. Group III that had been formed as a control group included the patients with a normal coronary angiogram. We compared the plasma ADMA, symmetric dimethylarginine, L-arginine/ADMA ratio among three groups. ResultsSeventy-four patients have been included in the study. Patients with good collateral development had lower plasma ADMA level in comparison with patients with poor collateral development (0.41±0.25 μmol/l vs. 0.70±0.23 μmol/l, P=0.001) and had similar plasma ADMA levels with the patients who have normal coronary arteries. When we compared L-arginine/ADMA ratio between good and poor collateral groups, we found that the patients with higher L-arginine/ADMA ratio have significantly better collateral development (270.8±168.0 vs. 120.9±92.1, P<0.001). In the analyses comparing Rentrop score with ADMA level and L-arginine/ADMA ratio, there were significant correlations (r=−0.444, P=0.008 and r=0.553, P=0.001, respectively). In multivariate analysis, ADMA level (odds ratio, 0.009; 95% confidence interval, 0.000–0.466, P=0.020) and L-arginine/ADMA ratio (odds ratio, 1.010; 95% confidence interval, 1.001–1.020, P=0.032) were independent predictors of collateral development. ConclusionIncreased plasma ADMA levels are related with poor coronary collateral development. ADMA may be responsible for the difference in coronary collateral vessel development among different patients with coronary artery disease. NO inhibitors that have a determinative relation with endothelial cell functions may be integral prerequisite in all steps of collateral development.


Gene | 2013

Screening for Fabry disease in patients undergoing dialysis for chronic renal failure in Turkey: Identification of new case with novel mutation

Ilyas Okur; Fatih Süheyl Ezgü; Gursel Biberoglu; Leyla Tümer; Yasemin Erten; Muzeyyen Isitman; Fatma Tuba Eminoğlu; Alev Hasanoglu

BACKGROUND Chronic renal failure (CRF) is a serious complication of Fabry disease (FD). The aims of the present study were to determine the prevalence of unrecognized FD in Turkish hemodialysis population and to investigate the molecular background. METHOD Primarily, α-galactosidase A (α-Gal A) activity was investigated on DBS in 1136 patients of both sexes who underwent dialysis for CRF in Turkey. The disease was confirmed by analyzing enzyme activity in leukocyte and GLA gene sequencing in all patients in whom α-Gal A level was 40% of normal or less. RESULTS Mean age of the patients (44.5% female, 52.5% male) was 56.46±15.85 years. Enzyme activity was found low with DBS method in 12 patients (four males, eight females). Two men, but no women, were diagnosed with FD by enzymatic and molecular analysis. In consequence of genetic analysis of a case, a new mutation [hemizygote c.638C>T (p.P214S) missense mutation in exon 5] was identified, which was not described in literature. Family screening of cases identified six additional cases. CONCLUSION As a result of this initial screening study performed on hemodialysis patients for the first time with DBS method in Turkey, the prevalence of FD was detected as 0.17%. Although the prevalence seems to be low, screening studies are of great importance for detecting hidden cases as well as for identifying other effected family members.


Journal of Pediatric Endocrinology and Metabolism | 1999

Plasma and erythrocyte vitamin E levels in children with insulin dependent diabetes mellitus.

Peyami Cinaz; Alev Hasanoglu; Aysun Bideci; Gursel Biberoglu

Vitamin E is considered to be one of the most important antioxidants. There is a trend today to supply diabetic children with vitamin E in order to prevent microvascular complications. In this study, our objective was to demonstrate validity of plasma and erythrocyte vitamin E levels in diabetic children. This study was conducted on twenty-five diabetic patients aged from 7-16 years and ten non-diabetic, age-matched healthy subjects as the control group. Vitamin E levels were measured by high-performance liquid chromatography. There was no significant difference between the mean plasma vitamin E levels of diabetic and control groups, 870.80 +/- 220.51 micrograms/dl and 891 +/- 221.21 micrograms/dl, respectively (p > 0.05). The mean erythrocyte vitamin E levels of diabetic and control groups were significantly different: 183.12 +/- 62.58 micrograms/dl and 246.90 +/- 68.26 micrograms/dl, respectively (p < 0.05). Erythrocyte vitamin E levels were significantly lower than plasma vitamin E levels in both groups. We further investigated whether a correlation exists between plasma and erythrocyte vitamin E levels and duration of diabetes, insulin dose and HbA1c measurements. However no correlation was found. In conclusion, measurement of erythrocyte vitamin E levels may be considered to be more valuable than plasma vitamin E levels in diabetic children and supplementation may be provided according to erythrocyte levels rather than plasma levels.


Forensic Science International | 2011

Very long-chain acyl CoA dehydrogenase deficiency which was accepted as infanticide.

Tuba F. Eminoglu; Leyla Tümer; Ilyas Okur; Fatih Süheyl Ezgü; Gursel Biberoglu; Alev Hasanoglu

Very-long-chain acyl-coenzyme A (CoA) dehydrogenase deficiency (VLCADD) (OMIM #201475) is an autosomal recessive disorder of fatty acid oxidation. Major phenotypic expressions are hypoketotic hypoglycemia, hepatomegaly, cardiomyopathy, myopathy, rhabdomyolysis, elevated creatinine kinase, and lipid infiltration of liver and muscle. At the same time, it is a rare cause of Sudden Infant Death Syndrome (SIDS) or unexplained death in the neonatal period [1-4]. We report a patient with VLCADD whose parents were investigated for infanticide because her three previous siblings had suddenly died after normal deliveries.


Journal of Child Neurology | 2008

Severe Infantile Hypotonia With Ethylmalonic Aciduria: Case Report

Cetin Okuyaz; Fatih Süheyl Ezgü; Gursel Biberoglu; Massimo Zeviani; Valeria Tiranti; Esat Yιlgör

An 8-month-old girl was admitted to an outpatient clinic with significant hypotonia and weakness. Organic acid analysis in urine revealed a significant increase in ethylmalonic acid. A deoxyribonucleic analysis revealed the presence of a 625G>A (G-to-A substitution at nucleotide 625) variant short-chain acyl-coenzyme A dehydrogenase gene polymorphism. With the clinical, biochemical and molecular findings, short-chain acyl-coenzyme A dehydrogenase deficiency was suspected. Because 625G>A and 511C>T (C-to-T substitution at nucleotide 511) genetic variations are also present in 14% of the general population, these are considered to be genetic sensitivity variations rather than causing a disease themselves and to result in possible short-chain acyl-coenzyme A dehydrogenase deficiency in the presence of environmental factors such as fever and hunger as well as cellular, biochemical, and other genetic factors. It was stressed that severe infantile hypotonia could also be the only manifestation of ethylmalonic aciduria spectrum disorders.

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Ali Cansu

Karadeniz Technical University

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