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Güler Ozer

Publications and source records attributed to Güler Ozer.

8 recordsLinked to original sources
PubMed2006

The importance of arginine mutation for the evolutionary structure and function of phenylalanine hydroxylase gene.

Phenylalanine hydroxylase (PAH) gene mutations were investigated in 23 (46 alleles) unrelated phenylketonuria (PKU) patients in Cukurova region. First, all exons of PAH gene were screened by denaturing high performance liquid chromatography (DHPLC), and then, the suspicious samples were analyzed by direct sequencing technique. Consequently, the following results were obtained: IVS10-11g-->a splicing mutation in 27/46 (58.7%), R261Q mutation in 7/46 (15.2%) and E178G, R243X, R243Q, P281L, Y386C, R408W mutations, each found in the frequency of 2/46 (4.3%). In many countries, Arginine mutations have the highest frequency among PAH gene mutations in PKU patients. Although, CpG dinucleotids are effective in mutations resulting in arginine changes, this finding originated from the studies on the causes of mutations rather than the studies on the importance of arginine amino acid. In our analyses, we have detected that a majority of mutations causing a change in arginine and other amino acids concentrated in exon 7 comprising the catalytic domain (residues 143-410) of PAH gene. Several studies has emphasized the role of arginine amino acid; with the following outcomes; arginine repetition is significant for RNA binding proteins, and for histon proteins in eukaryotic gene expression, and also arginine repetition occurring in the structure of signal recognition particle's (SRPs) as a consequence of post-translational processes is very important in terms of gene expression. Therefore, the role of arginine amino acid in PAH gene is rather remarkable in that it shows the role of amino acids in the protein/RNA interaction that has started in the evolutionary process and is still preserved and maintained in the motif formation of active domain structure due to its strong binding properties. Thus, such properties imply that both arginine amino acid and exon 7 is of great significance with regards to the structure and function of the PheOH enzyme.

Alleles↗
PubMed2005

Urinary neopterin levels in the different stages of pregnancy.

BACKGROUND/AIMS: Neopterin is a biochemical marker of activated cell-mediated immune response which increases in pathological conditions associated with cellular immune activation as well as in pregnancy where cellular immune response is predominant. The aim of this study was to determine the urinary neopterin level in each trimester of pregnancy and to determine if it can be used as a marker. METHODS: 104 healthy pregnant women (mean age 22.10 +/- 4.39 years; 36 in the first, 30 in the second and 38 in the third trimester) and 16 non-pregnant healthy women (mean age 20.94 +/- 4.48 year) were included. RESULTS: The mean urinary neopterin concentration of all pregnant women was higher than that of non-pregnant women (166.4 +/- 31.7 and 103.1 +/- 27.5 micromol/mol creatinine respectively, p < 0.01). The mean urinary neopterin levels in each trimester and non-pregnant women were 139.8 +/- 49.6, 131 +/- 40.2, 227.9 +/- 86.5 and 103.1 +/- 27.5 micromol/mol creatinine, respectively. Urinary neopterin levels were not significantly different between non-pregnant, first and second trimester groups, but were significantly higher in the third trimester than each of these groups (p < 0.05, p < 0.01 and p < 0.01 respectively). CONCLUSION: Urinary neopterin levels increase significantly in the third trimester probably due to more predominated cellular immunity. The pathologies causing cellular immune activation, especially in the first two trimesters can be predicted with urinary neopterin levels.

Adult↗
PubMed2003

Serum IL-1, IL-2, TNFalpha and INFgamma levels of patients with type 1 diabetes mellitus and their siblings.

Type 1 diabetes mellitus (DM) develops as a result of autoimmune destruction of the pancreatic beta-cells. The aim of this study was to explore possible associations between serum levels of cytokines, IL-1, IL-2, TNFalpha and INFgamma and metabolic parameters in children with type 1 DM and their non-diabetic siblings to determine whether these cytokines could be indicators of disordered immune regulation. The study population consisted of 41 children with type 1 DM, 32 non-diabetic siblings, and 28 healthy controls. Children with DM were divided into three subgroups: 1) newly diagnosed patients with diabetic ketoacidosis (ND + DKA), 2) newly diagnosed patients without DKA (ND - DKA), and 3) previously diagnosed patients (PD). The highest serum IL-1alpha level was found in the ND - DKA group, which was significant compared to both the ND + DKA (p < 0.05) and the siblings (S) (p < 0.005). IL-2 levels were similar among all groups. The highest TNFalpha level was observed in the ND + DKA group, which was significant against the ND - DKA (p < 0.05), PD (p < 0.001), S (p < 0.05), and control (C) (p < 0.005) groups. TNFalpha concentration in the PD group was significantly lower than those of S (p< 0.005) and C (p < 0.001) groups. The ND - DKA group had the highest INFgamma and this was statistically significant when compared with the S (p < 0.005) and C (p < 0.05) groups. Both the newly diabetics and all diabetics as a group had statistically significantly higher INFgamma levels than both the S (p < 0.01 for both) and C (p < 0.05 for both) groups. In the diabetics as a whole group, TNFalpha showed correlations with INFgamma (r = 0.370, p < 0.05). IL-1 showed correlation with TNFalpha (r = 0.368, p < 0.05) INFgamma (r = 0.796, p < 0.001) and IL-2 (r = 0.862, p < 0.001) in the all diabetics group. IL-2 was correlated with TNFalpha (r = 0.320, p < 0.05) and INFgamma (r = 0.754, p < 0.01) in the all diabetics group. In conclusion, our results suggest that proinflammatory cytokines TNFalpha, INFgamma, IL-1alpha and IL-2 may play important roles alone or in combination in the pathogenesis of type 1 diabetes mellitus.

Adolescent↗
PubMedDate not supplied

Early onset of diabetic nephropathy in a child with type 1 diabetes mellitus.

An 11-year-old prepubertal girl with a history of metabolically poorly controlled type 1 diabetes for six years was diagnosed with diabetic nephropathy based on persistent overt proteinuria, hypertension, and renal biopsy findings typical of diabetic nephropathy. This case illustrates that diabetic nephropathy can develop even before puberty when metabolic control of the disease is not sufficient.

Child↗
PubMedDate not supplied

Type II hyperprolinemia: a case report.

Hyperprolinemia type II (HP II) is a rare inherited metabolic disease due to the deficiency of pyroline-5-carboxylate dehydrogenase. It is generally believed to be a benign condition although some patients have neurological problems such as refractory convulsions. Here we report a six-year-old girl with HP II who admitted to our hospital with recurrent seizure refractory to multiple antiepileptic drugs. She was the third child of healthy, consanguineous parents. The family history was negative for neurological and renal disorders. On physical examination, she had no facial dysmorphy; the anthropometric measurements, and systemic and neurological examinations were normal. Mental and motor development was appropriate for her age. Laboratory findings revealed elevated levels of proline, glycine, and ornithine in serum and pyrroline-5-carboxylate and hydroxyproline in urine. Cerebral computerized tomography and magnetic resonance imaging were both normal. Electroencephalogram showed a very active epileptic abnormality; partial control of seizures was achieved by two antiepileptics. Increased plasma glycine and ornithine levels are the unique features of our case when compared to the other HP II cases reported in the literature.

1-Pyrroline-5-Carboxylate Dehydrogenase↗
PubMedDate not supplied

Fucosidosis with hypothyroidism: a case report.

Fucosidosis is a rare, autosomal recessive lysosomal storage disorder caused by a severe deficiency of alpha-L-fucosidase. Here we present a 27-month-old male who was referred to us for evaluation of developmental delay, which was first detected at age six months. His past medical history was also remarkable for recurrent pulmonary infections and myoclonic seiures. His family history revealed that he was the first living child from a consanguineous marriage. He had a younger sister who died at five months of age from pneumonia who had facial resemblance to the proband, developmental delay and a congenital heart defect. Physical examination revealed length: 81 cm (25-50p), weight: 10.2 kg (25-50p), and head circumference: 49 cm (50-75p). He had a coarse face, hepatomegaly and generalized spasticity. His initial laboratory examination revealed negative urine screening column chromatography for mucopolysaccharidosis. His X-ray findings were consistent with mild form of dysostosis multiplex. Based on clinical and laboratory features, fucosidosis was suspected. Fucosidase enzyme activity was zero. In addition to fucosidosis, thyroid function tests indicated primary hypothyroidism. This is, to the best of our knowledge, the fourth case of fucosidosis diagnosed in Turkey.

Bone and Bones↗
PubMedDate not supplied

Familial thyroxin-binding globulin excess with ichthyosis: a case report.

Thyroxin (T4) binding globulin (TBG) the major thyroid hormone transport protein in humans. Congenital or acquired problems lead to TBG excess. Inheritance of TBG excess follows an X-linked pattern. A 21-month-old boy with ichthyosis was referred to the Pediatric Endocrinology Clinic with high levels of thyroid hormones (TT3 = 325 ng/dl, TT4 23 microg/dl, FT3 = 3.49 pg/dl, FT4 = 1.44 ng/dl, TSH = 2.48 microIU/ml). He was clinically euthyroidic. Thyroid gland was normal in size and homogeneous. Thyroid autoantibodies were negative. TSH responded normally to thyroid releasing hormone (TRH) stimulus. TBG was elevated (56 microg/ml). Family investigation revealed high levels of TBG in mother grandfather, and an uncle. To our knowledge, no other TBG excess with ichthyosis has been reported in the literature.

Family Health↗