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Featured researches published by Orkide Donma.


Current Eye Research | 2002

Blood and lens lipid peroxidation and antioxidant status in normal individuals, senile and diabetic cataractous patients.

Orkide Donma; Eda Özkanat Yorulmaz; Hamiyet Pekel; Nezir Suyugül

Purpose. Oxidative mechanisms are believed to play an important role in the pathogenesis of cataract, the most important cause of visual impairment at advanced age. To determine the bodys antioxidant status as well as its lipid peroxidation levels, both blood and lens parameters were evaluated. Methods. This study was performed on the blood samples and lenses obtained from 46 patients diagnosed as having cataract and 20 control subjects. The control group was composed of 10 women and 10 men who do not smoke. Control subjects without any lens opacity or vacuoles when observed with a slit lamp were recruited on the same exclusion criteria as far as disease and treatment were concerned. No antioxidant medicines were used. They were all healthy individuals without any systemic diseases. Superoxide dismutase (SOD), glucose-6-phosphate dehydrogenase (G6PD), glutathione reductase (GSSG-Red) activities in red blood cell (RBC) lysates as well as whole blood glutathione (GSH) and plasma thiobarbituric acid reactive substances (TBARS), the indicator of lipid peroxidation concentrations, were determined quantitatively both in the blood samples and the lenses of the patients with senile and diabetic cataracts. Results. Whole blood GSH values, and erythrocyte SOD activities were significantly lower in the cataractous patients than those in the control group. The values in the diabetic cataractous group were also less than those in the senile cataractous group. Significantly decreased erythrocyte GSSG-Red and G6PD activities were detected in the diabetic cataractous group. Plasma TBARS values were higher both in the senile and diabetic groups when compared to those in the control group. Significantly decreased values were observed for GSSG-Red activities and TBARS values in the lenses of the senile cataractous patients in comparison with those in the diabetic cataractous patients. The lens GSH values were found to be higher in the senile cataractous group than the values obtained in the diabetic cataractous group. Conclusions. A strong correlation was found between lens GSH and lens TBARS concentrations in the diabetic group. This emphasized the vital role of GSH as an antioxidant in the lens over the other antioxidant parameters, e.g., enzymes, and the oxidative stress is at the highest level in lens.


Ophthalmic Research | 2003

Interleukin-8, Nitric Oxide and Glutathione Status in Proliferative Vitreoretinopathy and Proliferative Diabetic Retinopathy

Erdogan Cicik; Hasan Tekin; Solmaz Akar; Ozlem Balci Ekmekci; Orkide Donma; Lale Koldas; Sehirbay Ozkan

Purpose: To evaluate interleukin-8 (IL-8), nitric oxide (NO) and glutathione (GSH) profiles in vitreous humor and blood samples in patients with proliferative diabetic retinopathy (PDR) and in patients with proliferative vitreoretinopathy (PVR) and to compare the levels with those of controls. Patients and Methods: NO concentrations were determined by using the Greiss reaction in plasma and vitreous humor samples. GSH levels were determined in both blood and vitreous humor samples, using DTNB, a disulfide chromogen. Vitreous IL-8 were assayed by ELISA. Twenty-three patients with PDR, 18 patients with PVR and 21 cadavers as the control group were included in the study. Results: Plasma and vitreous NO levels were found to be25.6 ± 2.1 and 36.9 ± 3.0 µmol/l in patients with PDR, 27.0 ± 4.7 and 34.3 ± 2.9 µmol/l in patients with PVR and 17.4 ± 2.7 and 15.9 ± 1.4 µmol/l in controls, respectively. Vitreous humor and plasma NO levels did not show any statistically significant difference between PDR and PVR groups. However, the values for vitreous in both groups were significantly higher than those of controls (p < 0.0001). Although IL-8 levels in vitreous samples of patients with PDR were not significantly different (79.6 ± 9.7 pg/ml) from those of patients with PVR (42.2 ± 7.3 pg/ml) (p = 0.06), the levels in both groups were significantly higher than those of controls (19.0 ± 3.9 pg/ml) (p < 0.0001 and p < 0.05, respectively). Blood and vitreousGSH levels were found to be5.3 ± 0.4 µmol/g·Hb and 0.58 ± 0.16 µmol/l in patients with PDR and 8.4 ± 0.5 µmol/g·Hb and 15.7 ± 2.2 µmol/l in patients with PVR and 12.0 ± 1.1 µmol/g·Hb and 0.26 ± 0.03 mmol/l in controls, respectively. Vitreous and blood GSH levels were significantly lower in patients with PDR compared to those with PVR (p < 0.0001 for both). Conclusion: Elevated levels of vitreous and plasma NO and vitreous IL-8 in PDR and PVR implicate a role for these parameters in the proliferation in these ocular disorders. GSH concentrations both in vitreous and blood samples of the PVR and PDR patients were much less than those observed in the control group. Lower GSH concentrations detected in PDR in comparison with those in PVR in vitreous humor and to a lesser degree in blood may play an important role in pathogenesis of new retinal vessel formation in patients with PDR. This also suggests that oxidative stress may be involved in the pathogenesis of PVR and particularly that of PDR.


Biological Trace Element Research | 2002

Association of headaches and the metals.

Orkide Donma; M. Metin Donma

Lack of specific markers constitutes a problem during diagnosis of headache syndromes. Recently, some metals have gained importance as biological parameters for the diagnosis and during treatment. Low-ionized Mg and high-ionized Ca/Mg in patients with daily migrainous headaches were noted. The blood Na level was shown to increase before and during headache. Headache is also a symptom of the common cold for which zinc may be an effective therapy. The existing relationship between genetic markers of the cluster headache and the efficacy of lithium salts therapy was noted.Headache was also found to be associated with toxic metals. When the health effects of mercury were investigated, the most frequently observed symptom was cephalalgia. Continuous exposure to lead was concomitant with the appearance of symptoms such as headache.In relation to some metabolic links, metals may be introduced as possible biological markers for the diagnosis and during the therapy of different headache syndromes in future clinical trials and laboratory measurements.


Pediatrics International | 1999

Infant feeding and growth: a study on Turkish infants from birth to 6 months.

Mustafa Metin Donma; Orkide Donma

Abstract Background: To evaluate the impact of various feeding patterns on the physical growth and mental development of infants, particularly during the first 6 months of life, and to compare growth patterns of Turkish infants with those of infants living in various countries.


Brain & Development | 1997

The influence of feeding patterns on head circumference among Turkish infants during the first 6 months of life

Mustafa Metin Donma; Orkide Donma

The influence of various feeding patterns on physical growth and mental development of the infant, particularly during the first 6 months of life, is an important subject. Head circumference values of 172 healthy new-born infants were included in the study; 62 were exclusively breast-fed (BF), 58 were mixed-fed (MF) and 52 were formula-fed (FF). No significant differences were found in head circumference values between the groups at birth (BF 35.2+/-0.1, MF 35.1+/-0.1, FF 35.0+/-0.1 cm for boys and BF 35.0+/-0.1, MF 34.9+/-0.1, FF 34.8+/-0.1 cm for girls). At the end of the first month, the infants in the BF group (38.3+/-0.1 cm and 37.9+/-0.1 cm for boys and girls, respectively) had strikingly greater head circumference measurements than the others (MF 36.7+/-0.1, FF 36.6+/-0.1 cm for boys and MF 36.5+/-0.1, FF 36.4+/-0.1 cm for girls) (P < 0.05). However, in the subsequent 4-month period, the values detected in each group were almost the same. At the sixth month, head circumference-for-age values of infants in MF (42.6+/-0.1 cm for boys, 41.4+/-0.1 cm for girls) and FF (42.5+/-0.1 cm for boys, 41.5+/-0.1 cm for girls) were well below those of BF group (43.7+/-0.1 cm and 42.9+/-0.1 cm for boys and girls, respectively) and the standard curve (P < 0.05). These results suggest that exclusive breast feeding is sufficient during the first 6 months, the most important period of life.


Biochemistry | 2004

Iron, nitric oxide, and myeloperoxidase in asthmatic patients.

Ozlem Balci Ekmekci; Orkide Donma; E. Sardoğan; Nurhayat Yildirim; Omer Uysal; Hande Demirel; Tuncalp Demir

Plasma nitric oxide (NO), myeloperoxidase (MPO), and iron (Fe) levels were determined in bronchial asthma. The relations among these parameters in different stages of asthma were interpreted. Their association with airway inflammation observed in patients with bronchial asthma as well as the roles and the contributions to the pathological processes were evaluated. A total of 62 individuals, 32 asthmatics and 30 controls, were included into the scope of this study. Plasma nitric oxide metabolites (NOx) and MPO and Fe levels were determined by the Griess reaction, ELISA, and the automated TPTZ (2,4,6-tri[2-pyridyl]-5-triazine) method, respectively. In the asthmatic individuals, plasma NOx, MPO, and Fe concentrations were 133 ± 13 μM, 95 ± 20 ng/ml, and 159 ± 20 μg/dl, respectively; in the control group these values were 82 ± 11 μM, 62 ± 11 ng/ml, and 96 ± 9 μg/dl. Increased values were detected for plasma MPO (p > 0.05), NOx (p < 0.01), and Fe (p < 0.01) concentrations in asthmatic individuals. Considering the facts that NO modulates the catalytic activity of MPO and induces the expression of heme oxygenase as important contributors to the mechanisms causing free Fe release, it is concluded that elevated NOx, MPO, and Fe levels observed in the asthmatic group act in a concerted manner and appear to be involved in the pathogenesis of asthma.


Biological Trace Element Research | 1990

Zinc, copper, and magnesium concentrations in hair of children from Southeastern Turkey

Orkide Donma; Sacit Günbey; Mehmet Ali Tas; M. Metin Donma

Zinc, copper, and magnesium concentrations in hair were measured in groups of children varying in one condition—protein-energy malnutrition, ricketts, thalassemia, malignancy, cardiac failure, or after prolonged infection and in healthy controls. As compared with controls, copper and magnesium concentrations were low in all groups, whereas higher values were obtained for hair zinc. These results showed that a generalized copper and magnesium deficiency were observed in the southeastern part of Turkey. However, zinc deficiency couldn’t be detected as far as the hair zinc values were concerned, although all of the subjects fell within the 50 percentile limits for their age-appropriate weights and heights.


Biological Trace Element Research | 2006

Plasma paraoxonase activities, lipoprotein oxidation, and trace element interaction in asthmatic patients.

Ozlem Balci Ekmekci; Orkide Donma; Hakan Ekmekci; Nurhayat Yildirim; Omer Uysal; Emine Sardogan; Hande Demirel; Tuncalp Demir

Paraoxonase (PON1) protects low and high-density lipoproteins (LDL and HDL) against oxidation induced by reactive oxygen species formation facilitated by iron (Fe) and copper (Cu) ions. Plasma PON1, arylesterase, oxidized LDL (Ox-LDL), Cu, Fe, thiobarbituric acid-reactive substances (TBARS), lipid, lipoprotein, and apolipoprotein profile in bronchial asthma were determined and the relations among these parameters in different steps of asthma were interpreted. A total of 58 individuals, 30 asthmatics and 28 controls, were included into the scope of this study. Plasma PON1, arylesterase, and TBARS levels were measured spectrophotometrically. Determination of plasma oxidized LDL, Cu, and Fe levels were performed by enzyme-linked immunosorbent assay, atomic absorption spectrophotometry, and the automated TPTZ method, respectively. Apo-A-1 and Apo-B levels were determined immunoturbidometrically. Plasma total cholesterol, triglyceride, and HDL cholesterol levels were enzymatically determined. Plasma LDL levels were estimated using the Fridewald formula. The average plasma PON1 and arylesterase activities in the group of patients were lower than those of the individuals in the control group, but there was no statistically significant difference found between them (p>0.05). No significant difference was found in plasma Apo-A-1, Apo-B, total cholesterol, triglyceride, HDL, and LDL concentrations between the control and patient groups (p>0.05). Plasma oxidized LDL (p<0.05), Cu (p<0.01), Fe (p<0.01), and TBARS (p<0.001) levels in patients with asthma were found to be significantly higher than for the control group. Increases in Cu, Fe, lipid peroxidation, and oxidized LDL levels supported by relative decreases in PON1 activities observed in asthmatic patients might be introduced as the striking findings as well as the possible potential indicators of this airway disease, the prevalence of which has increased dramatically over recent decades.


Biological Trace Element Research | 1993

Hair zinc and copper concentrations and zinc : copper ratios in pediatric malignancies and healthy children from Southeastern Turkey

M. Metin Donma; Orkide Donma; M. Ali Taş

AbstractTwenty-eight healthy and forty-six children with malignancy admitted to the Pediatrics Oncology Clinic and Outpatient Clinic of Dicle University, Medical Faculty, Department of Pediatrics in 1989–1990 were included into this study. The children under investigation were divided into three groups. Group 1 consisted of 28 healthy children. Twenty-eight children with newly diagnosed malignant disease, before the start of treatment, formed Group 2. Group 3 consisted of eight of these 28 children together with 18 other children with malignancy in complete remission.1.Mean hair zinc and copper levels, and zinc/copper values for Group 2 were found to be 100.7±6.8 μg/g, 11.0±0.8 μg/g, and 10.0±0.8, respectively.2.The corresponding values for Group 3 were obtained as 143.5±6.3 μg/g, 7.6±0.4 μg/g, and 20.2±1.4.3.The values for Group 1 were 142.6±4.5 μg/g, 8.4±0.5 μg/g, and 19.0±1.4, respectively.4.The differences between control-active-phase and active-phase-remission groups were statistically significant (p<0.01), whereas almost the same values were obtained for the control and remission groups (p>0.05). These results were valid in cases where the comparisons of these three groups were performed also for the subgroups. It was shown that hair zinc and copper levels and zinc/copper values are useful parameters for the diagnosis and treatment of the children with malignancy because of the fact that hair reflects the integrated trace element concentrations of the body, not the present one.


Biological Trace Element Research | 2003

Angiotensin-Converting Enzyme and Metals in Untreated Essential Hypertension

Ozlem Balci Ekmekci; Orkide Donma; Aydın Tunçkale

Hpertension is an important health problem throughout the world and a risk factor for many diseases. Angiotensin-converting enzyme (ACE), a component of the renin-angiotensin system, has an important role in the regulation of blood pressure. Zinc (Zn), a trace element with important biological functions, is located in the catalytic site of ACE. Calcium (Ca), magnesium (Mg), sodium (Na), and potassium (K) also appear to be involved in hypertension pathogenesis. In this study, plasma ACE activities and Cat, Cai, Mg, Na, K, and plasma/erythrocyte Zn levels of 20 untreated patients with essential hypertension and 28 helthy individuals were evaluated. Plasma ACE activities (p<0.05) and erythrocyte Zn concentrations (p<0.001) were significantly higher in patients with essential hypertension than values of the control group. No significant difference was found between plasma Zn concentrations of the groups (p>0.05). Plasma Cat (p<0.001) and Mg levels (p<0.05) in essential hypertension were significantly lower than those of controls. Plasma Na, K, and Cai levels remained normal in essential hypertension. There are complex associations between metals and arterial pressure. Ca and Mg deficiencies seem to be associated with increased prevalence of hypertension. Increases in erythrocyte Zn may have a future potential use for diagnosis of hypertension.

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Murat Aydin

Namik Kemal University

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