PubMed Health⌕ Search

Biomedical subjects

M Ozbek

Publications and source records attributed to M Ozbek.

9 recordsLinked to original sources

Preprandial repaglinide decreases exogenous insulin requirements and HbA1c levels in type 2 diabetic patients taking intensive insulin treatment.

In this study, we investigated the effects of combining preprandial repaglinide to the insulin therapy for reducing the exogenous insulin requirements and serum HbA(1c) levels in type 2 diabetic patients whose blood glucose levels were previously regulated by multiple dose intensive insulin therapy. Fifty patients with type 2 diabetes who had been initially treated with oral antidiabetic agents without a satisfactory response were included in this study. After adequate glycemic control was achieved with intensive insulin therapy, the patients were divided into two subgroups. The first group continued with intensive insulin therapy. The second group received a combination of multiple insulin injections and oral repaglinide (1.5 mgr tid). The doses of insulin injections were gradually decreased accordingly in the second group. Both groups were followed-up for 3 months. Repaglinide was well tolerated and had no toxicity. A significant reduction regarding exogenous insulin requirements and serum HbA(1c) levels were demonstrated in patients taking preprandial repaglinide (p<0.01). Combining repaglinide to intensive insulin therapy could be a safe and effective alternative to intensive insulin therapy alone for the glycemic control and for reducing exogenous insulin requirements in type 2 diabetic patients.

Body Mass Index↗

Effects of pregnancy and lactation on bone mineral density, and their relation to the serum calcium, phosphorus, calcitonin and parathyroid hormone levels in rats.

The aim of this study was to evaluate the net changes in bone mineral density (BMD) during the reproductive cycle, and their relation with changes in serum calcium (Ca), phosphorus (P), PTH and calcitonin levels in rats. Twenty-seven female Wistar rats were included in this study. They were divided into three groups as pregnant, lactating and control groups. BMDs of lumbar vertebrates, femoral and tibial bones, and Ca, P, calcitonin and PTH levels were measured at the end of pregnancy, at the end of lactation and in nulliparous controls. In the pregnant group, the BMDs of rats were significantly higher in lumbar vertebrates, femoral and tibia bones than those of the control group (p<0.05). Their PTH and Ca levels were significantly lower than the control group (p<0.05). However, no statistically significant difference was found regarding P and calcitonin levels when compared to those of the control group. In the lactating group, the BMDs were significantly lower in lumbar vertebrates, femoral and tibia bones than those seen in the control and pregnant groups (p<0.05). Ca and PTH levels were significantly higher in lactating rats than in those of pregnant rats (p<0.005). Normal pregnancy increases BMD in rats, whereas lactation decreases it. Change in PTH levels is supposed to contribute to the mineralization and demineralization of the skeleton during pregnancy and lactation, respectively.

Animals↗

The prevalence of carotid artery calcification on the panoramic radiographs of patients with renal disease.

OBJECTIVES: To determine the prevalence of carotid calcification on dental panoramic radiographs in end-stage renal disease (ESRD) patients on haemodialysis and renal transplant recipients. METHODS: Panoramic radiographs of 69 adult patients with renal disease (34 with haemodialysis and 35 with renal transplantations) (age range 17-74 years; mean age 39.45 years) and 50 controls (age-match, free of systemic disease) were examined on panoramic radiographs for any unusual radiopacity adjacent to or just below the intervertebral space between C3 and C4. Patients with such calcifications were referred to ultrasound examination. Using Chi-squared tests, calcification prevalence rates were statistically compared. RESULTS: The statistical difference between renal disease patients and control group was significant (chi2 = 17.91, P < 0.001). On comparison of haemodialysis patients and renal transplant recipients with controls, statistical difference (P=0.007) was found to be significant. CONCLUSION: Carotid artery calcification was higher in haemodialysis patients and renal transplant recipients. These patients with such calcifications should be referred for further evaluation and treatment of carotid arteries, coronary arteries and vascular risk factors.

Adolescent↗

Bilateral bifid mandibular condyle.

Bilateral bifid mandibular condyles are rare and may appear as a congenital or developmental anomaly. A case of bilateral bifid mandibular condyles is reported. The patient had no history of trauma and no link was apparent with respect to the patient's medical history. In this case, the condition was an incidental panoramic radiographic finding. Magnetic resonance imaging findings revealed bilateral anterior disc displacement without reduction. The radiographic appearance of this anomaly and the literature on bilateral bifid condyles are reviewed.

Adult↗

Cranial deformation in a subadult sample from Değirmentepe (Chalcolithic, Turkey).

Human skeletal remains from the Chalcolithic period of Değirmentepe, Turkey, near the Euphrates River, display artificial cranial deformation of the circular type. Human skeletal remains belonging to 31 individual have been dated to the Chalcolithic period (second half of the fifth millennium BC, uncalibrated). The remains include foetuses, infants, children and juveniles; but no adult skeletons. Either the adults were buried elsewhere or flooding of the Euphrates dragged the adult remains away. Artificial cranial deformation was observed in 13 of the 31 subadults ranging in age from 1 month to 13-14 years. Değirmentepe villagers might have used one or two circular constricting bands with the intent of producing artificial head deformation. As far as Anatolia and the Near Eastern region is concerned, the widespread use of circular head deformation may be an indication of longer-distance trade and more need for ethnic markers.

Adolescent↗

Melatonin administration prevents the nephrotoxicity induced by gentamicin.

OBJECTIVE: To investigate the effect of melatonin on the antioxidant enzyme activity and renal tubular necrosis induced by gentamicin. MATERIALS AND METHODS: Twenty-four adult male Sprague-Dawley rats were divided into three equal groups. In group 1, the rats were injected with vehicle (controls), in group 2 they were injected with gentamicin for 5 days and in group 3 injected with gentamicin plus melatonin for 5 days. At 24 h after the last injection, rats were killed and the renal cortex separated from the medulla. Most of the cortex was homogenized but a small sample was fixed in formaldehyde solution for histological examination by light microscopy. Blood samples were also taken to assess the serum levels of urea, creatinine, Na+, K+ and gamma-glutamyl transpeptidase (gamma-GT); before death, urine samples were analysed for protein content. Crude extracts of the cortex were used to determine lipoperoxides, reduced glutathione (GSH-Px), catalase and superoxide dismutase (SOD). The results were compared using the Mann-Whitney U-test. RESULTS: Compared with the controls rats, gentamicin caused hyperproteinuria, an increase in the level of gamma-GT in serum, a marked increase in lipoperoxides and a significant decrease of GSH-Px, catalase and SOD activity in the kidney. In the rats in group 3 there was a marked restoration in lipid peroxidation, GSH-Px, catalase, SOD activity and proteinuria, and in gamma-GT in serum. In rats in group 2 there was widespread tubular necrosis (grade 2-4) but in rats in group 3 there was a marked reduction in the extent of tubular damage. There was no significant difference in serum levels of Na+, K+, blood urea nitrogen and creatinine. CONCLUSION: These results indicate that melatonin prevents the tubular necrosis induced by gentamicin in rats, presumably because it is a potent antioxidant and restores antioxidant enzyme activity in the rat kidney.

Animals↗

A model for evaluation of artificial oxygen carriers regarding circulation, respiration and metabolism in anesthetized spontaneously breathing guinea pigs.

The evaluation of artificial oxygen carriers requires experiments with suitable animals. Many investigators do this with the classical laboratory animal, the rat, but it has a quite different oxygen pressure of half saturation (p50 = 36 mmHg) from that of humans (26 mmHg). It was demonstrated that induced changes of the p50 value in animals provokes substantial changes in important cardiovascular parameters. Therefore, we decided to develop a guinea pig model for evaluation of artificial oxygen carriers, because it has a p50 of about 24 mmHg that is very similar to that of man. We found an anesthesia combination using fentanyl/droperidol/urethane to be very suitable for the narcosis, because important cardiovascular and respiratory parameters remain normal. Our model allows assessment of arterial pressure, oxygen uptake, carbon dioxide release, cardiac output, total peripheral resistance, shock index, blood lactate level, and, in particular, it allows to differentiate the oxygen transport in blood. We evaluated two hemoglobin-based oxygen carriers: bovine and porcine hemoglobin polymerized with glutaraldehyde in isoncotic solution (n = 3). Control experiments (n = 4) were done with an isotonic albumin solution. The protocol comprised a so-called exchange phase (I) with different degrees of hemodilution and a so-called time phase (II), an observation period with a hematocrit of 10% over about 3 hours. In the control group substantial changes in mean arterial pressure, total peripheral resistance, shock index, oxygen uptake and of blood lactate level were seen. All these effects were prevented by the artificial oxygen carriers tested. The carriers proved to be very effective, as small quantities in blood effectively restored these parameters, presumably via synergetic effects. Moreover, the experiments clearly revealed the limitation of hemodilution, at least in guinea pigs: below a hematocrit of 20% all parameters mentioned above changed significantly. The animal model presented proved to be appropriate for the evaluation of artificial oxygen carriers.

Anesthesia↗

[Does the metastatic behavior of sarcomas of the hand justify function-maintaining intervention?].

The dangers are emphasised of conservative surgery for soft-tissue malignancy of the hand, based on three cases. In the first, a fibrosarcoma which had developed in a longstanding fistula was treated by partial amputation, lymph node dissection and radiotherapy. Two recurrences arose locally at a later juncture. In the second case, a bone cyst diagnosed a "proliferative synovioma" was resected locally, only to recur on two further occasions being finally characterised as a spindle-cell sarcoma. In the third case, autopsy revealed metastatic Ewing's sarcoma in a patient initially treated by local resection of a "mesenchymal blastoma".

Adolescent↗