Isil Ozer
Samsun Ondokuz Mayis University, Child Metabolism, Faculty Member
- My special interests are development of medicinal foods for the nutritional treatment of metabolic diseases and the development of new diagnostic methods of metabolic diseases.edit
In our study 6 patients with renal amyloidosis who were managed in the Pediatric Department of Haydarpasa Numune Hospital between years 1990 and 1998 were evaluated retrospectively Four of them 66 6 demostrated phenotype 1 characteristics... more
In our study 6 patients with renal amyloidosis who were managed in the Pediatric Department of Haydarpasa Numune Hospital between years 1990 and 1998 were evaluated retrospectively Four of them 66 6 demostrated phenotype 1 characteristics of Familial Mediterranean Fever while the others 33 4 phenotype 2 characteristics In phenotype 1 subjects amyloidosis developed in a period from 3 to 9 years after the onset periodic attacks Three of four patients who had renal failure died in one year period Key words: renal amyloidosis familial Mediterranean fever
Research Interests:
Research Interests:
Research Interests: Medicine and Gynecology
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
The term rare disease is used for diseases with a prevalence of ˂ 1 per 2000 people in the community. For the first time in 1990, Sweden became the country that established an information center on rare diseases. Turkey has made the... more
The term rare disease is used for diseases with a prevalence of ˂ 1 per 2000 people in the community. For the first time in 1990, Sweden became the country that established an information center on rare diseases. Turkey has made the relevant legal arrangements in 2020. The largest group under this common roof is "Hereditary Metabolic diseases". The number of inherited metabolic diseases has reached a remarkable scope in the light of the rapidly accelerating developments in biochemistry, genetics, pharmacology, electronics sciences in 1902, when this name was first used, "Alkaptonuria" disease. In the light of the information obtained, 4 separate subgroups were created according to their common characteristics in order to produce solutions for this large group. Treatment options for metabolic disorders are both simple and complex. Diet therapy, cofactor therapy, enzyme replacement therapy (ERT), Substrate reduction therapy, chaperone therapy, tissue-organ-stem cell transplantation and gene therapy can be listed as these treatment options. Preimplantation genetics has been a rational solution to preventing disease formation, also supported by our ministry of health.
Research Interests:
ABSTRACT This study investigated behavioral phenotype, executive functions profile, and the existence of comorbid psychiatric disorders in children and adolescents with methylenetetrahydrofolate reductase (MTHFR) polymorphisms admitted to... more
ABSTRACT This study investigated behavioral phenotype, executive functions profile, and the existence of comorbid psychiatric disorders in children and adolescents with methylenetetrahydrofolate reductase (MTHFR) polymorphisms admitted to pediatric metabolism outpatient clinic. Internalizing problems, especially somatic complaints were common in patients with MTHFR. More than half of the cases had emotional control and initiating problems as executive function deficits. Attention-deficit/hyperactivity disorder was the most common psychiatric diagnosis, followed by anxiety disorder. Current findings emphasize that health care providers should be aware of the mental health needs of cases with MTHFR polymorphism in order to make plans of integrative physical and mental health care.
Research Interests:
Objective: In this study, we aimed to compare the prevalances of asthma, allergic rhinitis and chronic bronchitis in 13-15 years old school children living in the rural and urban areas of Tokat city from the Black Sea region, and to... more
Objective: In this study, we aimed to compare the prevalances of asthma, allergic rhinitis and chronic bronchitis in 13-15 years old school children living in the rural and urban areas of Tokat city from the Black Sea region, and to evaluate the impact of household and children characteristics on prevalences of allergic diseases in order to question the hygiene hypothesis. Materials and Methods: The study was conducted in the urban and rural parts of Tokat in 13-15 years old school children. The questionnaire included the ISAAC (International Study of Asthma and Allergy in Childhood) phase I questions. The items asking for chronic bronchitis and household characteristics were also included. Results: Eight hundred eighty (81%) children from the urban and 210 (19%) children from the rural Tokat were included in the study. In the study population, the prevalences of wheeze, ever and current (last 12 months), were 17% and 10.4%, respectively and both symptoms were significantly more com...
Research Interests:
Objective Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism. MTHFR C677T and A1298C polymorphisms are best-defined variants of MTHFR that were reported to be associated with epilepsy... more
Objective Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism. MTHFR C677T and A1298C polymorphisms are best-defined variants of MTHFR that were reported to be associated with epilepsy development. The aim of the study was to determine the incidence of interictal epileptiform discharges on electroencephalography (EEG) in asymptomatic children with C677T and A1298C polymorphisms who had no history of seizure. Methods Children with MTHFR C677T or A1298C polymorphisms who had normal neurological examination without a history of seizure were included in the study. Blood samples for serum folate, vitamin B12, and homocysteine levels were analyzed. Sleep and awake electroencephalograms (EEG) were recorded. Results A total of 102 children (50 girls and 52 boys) with a mean age of 59.4 ± 58.7 months were included in the study. Interictal epileptiform EEG discharges were detected in 3 children (2.9%). Conclusion There was no increase in the prevalence of interictal epileptiform discharges in seizure-free and asymptomatic children with MTHFR C677T and A1298C polymorphisms.
Research Interests:
Research Interests:
Research Interests:
Objectives Phenylketonuria (PKU) is a proteinopathy due to the deficiency of phenylalanine hydroxylase (PAH) enzyme. The pathological elevation of phenylalanine (Phe) and its metabolites in PKU is linked to neurological hallmarks and... more
Objectives Phenylketonuria (PKU) is a proteinopathy due to the deficiency of phenylalanine hydroxylase (PAH) enzyme. The pathological elevation of phenylalanine (Phe) and its metabolites in PKU is linked to neurological hallmarks and mental disabilities. The aim of this study was to examine the hypothesis that high levels of Phe caused endoplasmic reticulum (ER) stress in PKU patients. Methods We primarily evaluated ER stress markers glucose-regulated protein78 (GRP78) and C/-EBP homologous protein (CHOP), and thiobarbituric acid-reactive substances (TBARS) as a biomarker of oxidative stress in leukocytes and correlated it with blood Phe values from patients with PKU. Patients in this study were selected from individuals who were diagnosed with PKU as a result of the national neonatal screening program and undergone treatment at our university hospital. The subjects were divided into four groups: healthy controls, patients with hyperphenylalaninemia (HPA), BH4-responsive patients wi...
Research Interests:
Giriş: Primer Hiperoksalüri Tip I (PH1) Pridoksal 5 Fosfat bağımlı Alanin Gliksilat Aminotransferaz (AGT) enzimi bozukluğudur. Konjenital müsküler distrofiler (CMDs) nadir bir kalıtsal hastalık grubudur. Ullrich Konjenital Müsküler... more
Giriş: Primer Hiperoksalüri Tip I (PH1) Pridoksal 5 Fosfat bağımlı Alanin Gliksilat Aminotransferaz (AGT) enzimi bozukluğudur. Konjenital müsküler distrofiler (CMDs) nadir bir kalıtsal hastalık grubudur. Ullrich Konjenital Müsküler Distrofi (UCMD) ciddi klinik bulgusu olan CMD’lerden biridir. Olgu: Oniki buçuk yaşında kız hasta hiperoksalüri bulgusu ile başvurdu. Hastanın COL6A2 gen mutasyonlu UCMD hastalığı tanısı ile izlenmekte olduğunu öğrendik. Aynı zamanda PH1 ile ilişkili AGT Pro 11 Leu/Ile 340 Met homozigot mutasyonu da bulundu. Pridoksal fosfat tedavisinden sonra, oksalozis ile ilişkili cilt bulguları düzeldi, idrar oksalat/kreatinin oranı azaldı. Sürpriz olarak, hastanın UCMD ile ilişkili kas bulguları da belirgin düzeldi. Tartışma: Pridoksal fosfatın, kollajen tip VI ile ilişkili miyopatilerin günümüzde sadece semptomatik olan tedavisinde ne kadar etkili olacağı konusunda ileri tetkikler yapılması gerektirmektedir.
Research Interests:
Kwashiorkor is a serious nutritional disease. The 7-month-old male patient presented with severe metabolic acidosis and elevated liver enzymes. His condition was similar to fatty acid oxidation defect. He was taken to the hospital on the... more
Kwashiorkor is a serious nutritional disease. The 7-month-old male patient presented with severe metabolic acidosis and elevated liver enzymes. His condition was similar to fatty acid oxidation defect. He was taken to the hospital on the previous day with complaints of poor sucking and difficulty breathing. Treatment of upper respiratory tract infection was provided and then he returned to his home. He was cyanotic in bed after 12 hours. The patient, who was taken to the hospital unconscious and not fed for 12 hours, was not given any food orally in the first health center. Until laboratory tests are done, only iv electrolyte and a fluid containing dextrose were given. When the laboratory results were found to be significantly pathological, he was urgently referred to our hospital 4 hours after the admission. The content of the iv treatment applied at the time of referral was not clearly written. Low electrolytes, uric acid, liver enzymes, urea and creatinine elevation were detected...
Research Interests:
Cat-scratch disease can be transmitted from cats and dogs in winter. It is usually self-limited and caused by Bartonella henselae. It may cause serious symptoms, including neurological findings, especially in immune-deficient patients. A... more
Cat-scratch disease can be transmitted from cats and dogs in winter. It is usually self-limited and caused by Bartonella henselae. It may cause serious symptoms, including neurological findings, especially in immune-deficient patients. A female patient was referred to our outpatient clinic at the age of 3 years and 10 months with a preliminary diagnosis of neurodegenerative metabolic disease. Her complaints began after a stray cat scratched her. We found out that the hospital to which she was admitted provided only local wound care due to her history of contact with a cat and that she was vaccinated against rabies. Her body temperature increased, her neck lymph nodes became swollen, and she developed otitis and mastoiditis after 1 month. Additionally, we discovered that she had deteriorated in her walking ability after 6 weeks and developed hand tremors after 10 weeks. It was discovered that previous centers to which the patient applied did not question cat contact. All metabolic te...
Research Interests:
Vitamin C is the cofactor in biosynthesis of collagen, catecholamines and iron metabolism. The clinical features of scurvy may resemble metabolic disorders and hamper early diagnosis. A 2-year, 5-months old male child was admitted to... more
Vitamin C is the cofactor in biosynthesis of collagen, catecholamines and iron metabolism. The clinical features of scurvy may resemble metabolic disorders and hamper early diagnosis. A 2-year, 5-months old male child was admitted to hospital with complaints of growth retardation, irritability, joint deformities, and frequent illness. Severe malnutrition, coarse facial appearance, gingival hypertrophy, organomegaly, osteoporosis and anemia were detected. Screening for inborn errors revealed generalized aminoaciduria and elevated blood free carnitine. His dietary history revealed poor consumption of vitamin C. Vitamin C level was 0.05 mg/L (n: 4-21) in plasma, 2.85 mg/24 hour (n:10-30) in urine, and 1.03 mg/6 hours in urine after intravenous loading. The patient was given 200 mg/day vitamin C orally. Irritability and bone sensitivity decreased after the first two days. Clinical features in scurvy resemble symptoms observed in some metabolic disorders. Careful clinical evaluation,dietary history and vitamin C assay may exclude uneccessary metabolic work-up.
Research Interests:
Research Interests:
Research Interests:
Methylenetetrahydrofolate reductase reduces methyltetrahydrofolate, a cosubstrate in the remethylation of homocysteine, from methylenetetrahydrofolate. Congenital defects, hematologic tumors, and intrauterine growth retardation can occur... more
Methylenetetrahydrofolate reductase reduces methyltetrahydrofolate, a cosubstrate in the remethylation of homocysteine, from methylenetetrahydrofolate. Congenital defects, hematologic tumors, and intrauterine growth retardation can occur during childhood. This study evaluated clinical and laboratory treatment approaches in children diagnosed with methylenetetrahydrofolate reductase mutations. Our group included 23 boys and 14 girls, aged 103.4 ± 70.8 months S.D. Clinical findings of patients and homocysteine, vitamin B12, folate, hemogram, electroencephalography, cranial magnetic resonance imaging, and echocardiography data were evaluated in terms of treatment approach. Our patients' findings included vitamin B12 at 400.4 ± 224.6 pg/mL S.D. (normal range, 300-700 pg/mL), folate at 10.1 ± 4.5 ng/mL S.D. (normal range, 1.8-9 ng/mL), and homocysteine at 8.4 ± 4.7 μmol/L S.D. (normal range, 5.5-17 μmol/L). Eighty-eight percent of patients demonstrated clinical findings. In comparisons involving categorical variables between groups, χ(2) tests were used. No relationship was evident between mutation type, laboratory data, and clinical severity. All mothers who had MTHFR mutations and had babies with sacral dimples had taken folate supplements during pregnancy. To avoid the risk of neural tube defects, pregnant women with a MTHFR mutation may require higher than normally recommended doses of folic acid supplementation for optimum health.
Research Interests: Electroencephalography, Folic acid, Adolescent, Intellectual Disability, Humans, and 15 moreChild, Mutation, Female, Male, Infant, Homocysteine, Consanguinity, Neural Tube Defects, Neurosciences, Congenital Defect, Nino, Magnetic resonance image, Child preschool, Methylenetetrahydrofolate Reductase, and Paediatrics and reproductive medicine
Research Interests:
Methylenetetrahydrofolate reductase reduces methyltetrahydrofolate, a cosubstrate in the remethylation of homocysteine, from methylenetetrahydrofolate. Congenital defects, hematologic tumors, and intrauterine growth retardation can occur... more
Methylenetetrahydrofolate reductase reduces methyltetrahydrofolate, a cosubstrate in the remethylation of homocysteine, from methylenetetrahydrofolate. Congenital defects, hematologic tumors, and intrauterine growth retardation can occur during childhood. This study evaluated clinical and laboratory treatment approaches in children diagnosed with methylenetetrahydrofolate reductase mutations. Our group included 23 boys and 14 girls, aged 103.4 ± 70.8 months S.D. Clinical findings of patients and homocysteine, vitamin B12, folate, hemogram, electroencephalography, cranial magnetic resonance imaging, and echocardiography data were evaluated in terms of treatment approach. Our patients' findings included vitamin B12 at 400.4 ± 224.6 pg/mL S.D. (normal range, 300-700 pg/mL), folate at 10.1 ± 4.5 ng/mL S.D. (normal range, 1.8-9 ng/mL), and homocysteine at 8.4 ± 4.7 μmol/L S.D. (normal range, 5.5-17 μmol/L). Eighty-eight percent of patients demonstrated clinical findings. In comparisons involving categorical variables between groups, χ(2) tests were used. No relationship was evident between mutation type, laboratory data, and clinical severity. All mothers who had MTHFR mutations and had babies with sacral dimples had taken folate supplements during pregnancy. To avoid the risk of neural tube defects, pregnant women with a MTHFR mutation may require higher than normally recommended doses of folic acid supplementation for optimum health.
Research Interests: Electroencephalography, Folic acid, Adolescent, Intellectual Disability, Humans, and 15 moreChild, Mutation, Female, Male, Infant, Homocysteine, Consanguinity, Neural Tube Defects, Neurosciences, Congenital Defect, Nino, Magnetic resonance image, Child preschool, Methylenetetrahydrofolate Reductase, and Paediatrics and reproductive medicine
Research Interests:
Research Interests: Genetics, Geography, Genetic Epidemiology, Genomics, Epigenetics, and 15 moreAdolescent, Cytogenetics, Child, Female, Clinical Genetics, Enzyme, Clinical Sciences, Adult, Enzyme activity, Amino Acid Sequence, Autosomal Recessive, Haplotype, Founder Effect, DNA mutational analysis, and Child preschool
Quantification of nitisinone, 2-(nitro-4-trifluoromethylbenzoyl)1,3-cyclohexanedione (NTBC) has been repeatedly described. Nevertheless monitoring of NTBC has not yet become part of routine therapy surveillance in tyrosinaemia type I... more
Quantification of nitisinone, 2-(nitro-4-trifluoromethylbenzoyl)1,3-cyclohexanedione (NTBC) has been repeatedly described. Nevertheless monitoring of NTBC has not yet become part of routine therapy surveillance in tyrosinaemia type I (OMIM 276700). We developed a blood spot test to facilitate collection and transport of samples. Furthermore, the test material can be used for determination of other parameters like tyrosine and succinylacetone. For quantification of NTBC in blood spots filter paper discs of 3.2mm diameter were extracted with 150 μL methanol containing mesotrione as internal standard (IS). Analysis was done by UPLC-MS/MS on a Xevo mass spectrometer (ESI+), (MRM). Parent ions were 330.05 for NTBC and 340.05 for IS, daughter ions were m/z 217.95 and m/z 125.95 for NTBC, and m/z 227.95 and m/z 103.95 for IS. The calibration curve for NTBC in blood spots was linear from 0.1 μmol/L to 100 μmol/L. Recovery exceeded 73.1%, CV intraday and interday were below 9.6%. Instrumental run time was 2.5 min. Sensitivity of the method was 0.1 μmol/L. NTBC concentrations in plasma were higher than in blood spots by a factor of 1.56 ± 0.13. As demonstrated in patients with tyrosinaemia type I quantification of NTBC by UPLC-MS/MS in blood spots is feasible and gives valuable information for monitoring NTBC treatment.