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Biomedical subjects

M Yilmaz

Publications and source records attributed to M Yilmaz.

At least 19 recordsLinked to original sources

Efficacy of methylprednisolone in acute experimental cauda equina injury.

In this experimental study the efficacy of methylprednisolone was investigated by neurophysiological and histopathological evaluation in a rabbit cauda equina model where injury was produced with an aneurysm clip (closed pressure 192 gr). High dose methylprednisolone (kg/30 mg) was administered by intravenous infusion in the 8th, 16th and 24th hours after injury followed by infusion of the same dosage every 6 hours for 24 hours. Nerve conduction velocity was measured before and early after trauma and 3 weeks after injury. Both neurophysiological and histopathological investigations demonstrated the neuroprotective effectiveness of methylprednisolone if it was given in the 8th hour after trauma. Although recovery was observed its efficacy was less pronounced when it was given in the 16th and 24th hours.

Animals↗

Therapeutic effects of intracarotid infusion of spermine/nitric oxide complex on cerebral vasospasm.

BACKGROUND: Vasospasm is one of the underlying causes of morbidity and mortality in subarachnoid haemorrhage (SAH). The therapeutic effects of intracarotid infusion of spermine/nitric oxide complex (SPER/NO) on cerebral vasospasm in an experimental model of SAH were investigated. METHOD: Twenty-four adult male New Zealand white rabbits (2.6-3.4 kg in weight) were randomly divided into four groups (n=6), as follows: (I) control group (without SAH and drug), (II) SAH alone group (with SAH, without drug), (III) SAH placebo group (with SAH and saline), and (IV) SAH-SPER/NO group (with SAH and SPER/NO). The fresh autologous non-heparinized blood was injected into the cisterna magna to induce a SAH, after 24 hour SAH, the substance (saline or SPER/NO) was delivered to animals. All rabbits were scarified at 48-hours of induced SAH. The basilar artery with surrounding tissue was removed from the cranium and processed for paraffin embedding. Histopathological and stereological examinations of the basilar artery were done. FINDINGS: In the SPER/NO treated group of rabbits, the histopathological changes were less severe than in the SAH-alone and SAH-placebo groups. Regarding the intracarotid pressure, there was a statistically significant difference between SAH-alone and SAH-SPER/NO groups and also between SAH-SPER/NO and control groups (p<0.05). The mean cross sectional area of basilar arteries was 0.26 mm(2) in the control, whereas in SAH alone, placebo and SAH-SPER/NO groups were 0.13, 0.15 and 0.20 mm(2), respectively. INTERPRETATION: It is well known that NO is a critical substance involved in cerebral vascular dynamics. Present results indicate that treatment of vasospasm with SPER/NO in SAH may be promising. However, further studies should be done on this substance to clarify its effect on vasospasm before using the drug in clinical situations.

Animals↗

Significance of the catechol-O-methyltransferase gene polymorphism in migraine.

The objective was to assess the significance of the catechol-o-methyltransferase (COMT) enzyme polymorphism in migraine. For this reason, 62 migraineurs and 64 healthy volunteers were included in the study. The analysis of COMT polymorphism was performed using PCR. The H/H genotype was more frequent in the control group than in the patients group (P=0.032). The homozygous or heterozygous L allele was over represented in the migraineurs compared with the controls (P=0.013). The L/L genotype was over represented in the migraineurs who also had a family history of migraine (P=0.003). There was no relationship between aura and COMT genotypes. In conclusion, the COMT polymorphism may be of potential pharmacological importance regarding the individual differences in the metabolism of catechol drugs in migraineurs. Although altered catecholamine activity due to polymorphism of COMT gene may be one of the mechanisms involved in the pathogenesis of migraine, these mechanisms are not related to presence or absence of aura.

Adult↗

Association of the T102C polymorphism of 5-HT2A receptor gene with aura in migraine.

OBJECTIVE: To find out the significance of the 5-HT2A receptor gene polymorphism in migraine. STUDY DESIGN: A PCR study in which 61 migraineurs and 44 healthy controls were included. METHODS: The T102C polymorphism of the 5-HT2A receptor gene was studied. The results of the migraineurs and controls were compared. The relationship between the gene polymorphism and aura was also assessed. RESULTS: The representations of the 5-HT2A genotypes were similar in migraineurs and controls (p>0.05) as well as in the male and female migraineurs (p>0.05). The family history of migraine did not associate with 5-HT2A receptor gene polymorphism (p>0.05). There was a significant relationship between the presence of C/C genotype and migraine with aura (p=0.02) while C/T and T/T genotypes were over represented in the patients with migraine without aura (p<0.01). CONCLUSION: The T102C polymorphism of the 5-HT2A receptor gene is not directly related to the increased risk of migraine. The associations between the genotypes of this gene and aura may suggest that 5-HT2A receptor gene polymorphism may be involved in determining the subtypes of or accompanying symptoms in the migraine disease.

Adult↗

Significance of serotonin transporter gene polymorphism in migraine.

OBJECTIVE: To elucidate significance of the serotonin transporter gene (STG) polymorphism in migraine, and to address the polymorphic patterns of STG, both in the migraineurs and healthy people in this country. STUDY DESIGN: A PCR study of STG in 52 migraineurs and 80 healthy controls. METHODS: Using the PCR technique, STG polymorphism was studied in the DNA obtained from leukocytes of the patients and healthy controls. Polymorphism of the two regions (VNTR and 5-HTTLPR) of STG was assessed. RESULTS: VNTR STin 2.10 and STin 2.12 alleles were detected in migraineurs and healthy controls. Both homozygous and heterozygous STin 2.10 allele predominated in the migraine group (p=0.01), while STin 2.12 allele was more frequent in the healthy controls (p=0.02). There was no relationship between the migraine type, family history of migraine and STG polymorphism. CONCLUSION: STin 2.10 and STin 2.12 alleles of VNTR are frequent in this country. While the presence of STin 2.10 allele increases the risk of migraine, 5-HTTLPR polymorphism is not associated with this risk.

Adult↗

Visual evoked potential changes in migraine. Influence of migraine attack and aura.

OBJECTIVE: To assess the visual evoked potential (VEP) changes in migraines with and without aura. STUDY DESIGN: A clinical study in which the VEP results of 45 migraineurs (study group) and 22 healthy volunteers (control group) were compared. Of 45 migraineurs, 29 had migraine with aura (MA) and 16 had migraine without aura (MOA), and they were examined both during and between the migraine attacks. METHODS: The patients and healthy controls underwent VEP assessment. On VEP recording, mono-ocular stimulation was performed by means of the pattern reversal check board. The latencies of N1, P1 and N2, and the N1--P1 amplitude were noted. The following comparisons were made between NI, P1 and N2 latencies and N1--P1 amplitudes of the migraine and control groups; during and between attack the VEP results of the patients with MA and MOA. RESULTS: The VEP results of the migraineurs and healthy controls were similar (P>0.05). The during attack results of MA, during and between attack results of MOA, and the results of the control group were also similar (P>0.05). N2 latency significantly elongated in patients with MA in the attack free period than it was during the attack (P=0.01), and was also longer than it was in the control group (P=0.01). CONCLUSIONS: There is involvement of the visual pathway in MA rather than MOA, and differentiation between these subtypes of the migraine disease may be performed on the basis of VEP findings manifesting by the prolongation of the N2 wave latency. This contention should be confirmed by further studies.

Adolescent↗

Assessment of DNA strand breakage by comet assay in diabetic patients and the role of antioxidant supplementation.

Diabetes patients often show increased production of reactive oxidative species (ROS) together with vascular complications. The presence of these ROS may lead to increased DNA damage in peripheral blood lymphocytes that may be revealed by the comet assay. To test whether DNA is damaged in diabetes, peripheral blood samples were taken from 30 control individuals and 63 diabetic patients (15 insulin dependent (IDDM) and 48 non-insulin dependent (NIDDM)) and the alkaline comet assay was used to evaluate background levels of DNA damage. Significant differences were detected between control and diabetic patients in terms of frequencies of damaged cells. The extend of DNA migration was greater in NIDDM patients by comparison with IDDM patients which might indicate that IDDM patients are handling more oxidative damage on a regular basis. Smoker individuals had higher frequencies of cells with migration by comparison with the non-smokers in both groups. Also, clear differences between patients on placebo and on Vitamin E supplementation for 12 weeks were observed on the basis of the extend of DNA migration during single cell gel electrophoresis.

Adult↗

Increased plasma adrenomedullin in patients undergoing percutaneous transluminal coronary angioplasty.

OBJECTIVES: Adrenomedullin (ADM) production and secretion have been reported in endothelial cells. The present study was designed to assess whether coronary angiography (CA) and percutaneous transluminal coronary angioplasty (PTCA) affect plasma ADM levels. DESIGN AND METHODS: We measured plasma concentrations of ADM using a specific radioimmunoassay method in patients undergoing coronary angiography or PTCA before and after a 5-minute procedure. Patients were divided into three groups; group I: normal coronary angiography group (11 males, 10 females; mean age 55.90 +/- 11.03 yrs), group II: coronary artery disease (CAD), only coronary angiography performed (14 males, 8 females; mean age 60.95 +/- 9.80 yrs), group III: PTCA performed in patients with CAD (35 males, 11 females; mean age 55.89 +/- 10.41 yrs). RESULTS: The plasma ADM levels and left ventricular end diastolic pressures measured before the procedure were similar in the three groups (p > 0.05). Plasma ADM levels were 13.98 +/- 2.26, 15.59 +/- 6.70, 17.15 +/- 8.47 pg/ml respectively. ADM levels measured after CA showed no significant difference in group I (13.75 +/- 1.75 pg/ml) or group II (16.50 +/- 7.18 pg/ml) (p > 0.05). A marked elevation was observed in group III with ADM levels of 27.31 +/- 12.27 pg/ml after PTCA (p < 0.01). The ADM levels observed in group III after PTCA were significantly higher than those of group I and group II after coronary angiography (p < 0.001). CONCLUSION: The results of our study show an increase of ADM after PTCA but not after coronary angiography in patients with or without CAD. We think that the increase of ADM levels may be due to cardiac secretion from endothelial and smooth muscle cells following balloon injury.

Adrenomedullin↗

Bronchiectasis: still a problem.

The prevalence of bronchiectasis (BR) has decreased significantly in industrialized countries, but is still commonplace in developing countries. We evaluated the causes and clinical features of BR in 23 children (13 boys (57%) and 10 girls (43%), with a mean age of 8.45 +/- 4.02 years). Infection was the major cause of BR in our region. In 8 patients, BR developed after tuberculosis or pneumonia, was associated with immune deficiency syndromes in 4 children, and with asthma in 4. Cystic fibrosis was diagnosed in 4 cases and ciliary dyskinesia in 3. In 10 patients, only one lobe was involved. Bronchiectatic lesions were most commonly found in the left lower lobe and were observed in 7 patients. Multilobar involvement was found in 13 patients. The initial treatment was primarily medical, but in 2 patients whose medical therapy failed, pulmonary resection was carried out. Three patients died from severe pulmonary infection and respiratory failure.

Adolescent↗

The role of Tc-99m RBC scintigraphy in the differential diagnosis of orbital cavernous hemangioma.

The cavernous hemangioma is the most common benign orbital tumor in adults. Its presentation is during the forth to fifth decades with a slowly progressive unilateral proptosis. Intraconal cavernous hemangiomas may be difficult to differentiate from other intraconal lesions such as schwannomas, meningiomas and hemangiopericytomas. We report a case of orbital cavernous hemangioma diagnosed by Tc-99m RBC scintigraphy. Tc-99m RBC scintigraphy revealed a typical scintigraphic pattern in which there is intense focally increased uptake on the delayed image. We conclude that Tc-99m RBC scintigraphy can be a useful method in the differential diagnosis of orbital cavernous hemangioma as in hepatic hemangioma.

Diagnosis, Differential↗

The role of technetium-99m-HMPAO-labeled WBC scintigraphy in the diagnosis of orbital cellulitis.

Bacterial orbital cellulitis is an infection of the soft tissues behind the orbital septum. Cellulitis is seen as a poorly defined area of increased CT density or T2 signal intensity within the fat. There is an amorphous enhancement following contrast infusion. Radiolabeled leukocytes or granulocytes are now established widely as a means of localizing various forms of inflammatory disease and infections. We report a case of orbital cellulitis detected with Tc-99m-HMPAO-labeled WBC scintigraphy and three-phase bone scintigraphy. Tc-99m-HMPAO-labeled WBC scintigraphy was superior to bone scintigraphy in delineating the extension and limits of the infectious process in the orbita. Tc-99m-HMPAO-labeled WBC scintigraphy is appropriate in the investigation of such infectious lesions, leading to early diagnosis and therapy to avoid severe complications.

Cefotaxime↗

Cytokine levels in serum of patients with juvenile rheumatoid arthritis.

We investigated serum levels of interleukin (IL)-1beta, IL-6, IL-8, IL-12 and tumour necrosis factor (TNF)-alpha in JRA patients during both active and inactive phases of the disease. The systemic JRA patients had the highest IL-1beta and IL-6 levels during both active and inactive periods. In the systemic group IL-1beta, IL-6 and IL-12 levels during the active period were elevated compared to the inactive period (p = 0.0173, p = 0.0359 and p = 0.0117, respectively). Levels of these cytokines during the inactive stage were still greater than those of controls. IL-8 and TNF-alpha levels during both active and inactive periods were comparable to controls. IL-1beta correlated strongly with CRP and ESR (p = 0.008 and p = 0.031, respectively). IL-6 correlated significantly with CRP (p = 0.002). IL-12 levels were found to be correlated with ESR and CRP (p = 0.03 and p = 0.04, respectively). In active polyarticular JRA patients, IL-6 levels were elevated compared to the inactive phase, and the control (p = 0.001) IL-12 levels decreased significantly with clinical remission (p = 0.018). There was a strong correlation between 11-12 levels and number of joint with limited motion (p = 0). In oligoarticular JRA patients, IL-12 levels during active period were greater than in the controls and there was a marked decrease in IL-12 levels when the patients entered the inactive phase (p = 0.001) In conclusion, IL-1beta, IL-6 and IL-12 may play an important role in JRA and may be used as a marker of disease activity.

Adolescent↗

Ossified thoracic spinal meningioma in childhood: a case report and review of the literature.

Spinal ossified meningiomas are extremely rare. This is a report of a study on a 15-year-old boy with thoracic spinal ossified meningioma. The meningioma was resected totally. Histopathological examination revealed a transitional meningioma (psammomatous+meningothelial). Immunohistochemically, Ki 67 antibody was applied but no positive staining was present. The surgical and pathological aspects of spinal ossified meningiomas were reviewed.

Adolescent↗

Bidirectional Glenn shunt in an infant with prune-belly syndrome.

The prune-belly syndrome (PBS) usually is described as a deficiency of the anterior abdominal muscle involving bilateral cryptorchidism and urinary tract malformations. In this report, we will present an eleven-month-old boy with PBS associated with a complex cardiac anomaly. A bilateral bidirectional Glenn shunt was performed with the diagnosis of isolated dextrocardia, single ventricle, pulmonary atresia, incomplete A-V septal defect, hemiazygos continuity, persistent right superior vena cava, patent ductus arteriosus-dependent pulmonary blood flow. The patient required special consideration for postoperative pulmonary care.

Abdominal Muscles↗

Clearance of Tc-99m DTPA aerosol in mismatched and matched pulmonary perfusion defects.

PURPOSE: To evaluate clearance changes of Tc-99m DTPA aerosol in mismatched and matched pulmonary perfusion defects. MATERIALS AND METHODS: Twenty-one patients (14 women, 7 men; mean age, 51 +/- 14 years) with possible pulmonary embolism were included in the study. On the day after perfusion (Q) scintigraphy with 5 mCi Tc-99m MAA, radioaerosol inhalation scintigraphy was performed using 45 mCi Tc-99m DTPA. Immediately and 45 minutes after the inhalation, early and delayed inhalation images (EI and DI, respectively) were obtained. Group 1 included 11 patients with mismatched defects who had a high probability of pulmonary embolism according to the Q/EI scan results. Group 2 included 10 patients with matched defects who had a low probability of PE. Contralateral normal lungs of 7 patients in group 2 served as controls (group 3). In groups 1 and 2, regions of interest were drawn over the mismatched and matched perfusion defects where they were best visualized, and this region of interest was mirrored to the same region on EI and DI images. For the control group, this was done in the contralateral normal lung. Mean counts in each region of interest were used for quantitative analysis, and the percentage clearance ratio was calculated using the following formula: early counts - late counts/early counts x 100. RESULTS: The average percentage clearances for the three groups were as follows: group 1, 37% +/- 10%; group 2, 21% +/- 4%; group 3, 24% +/- 7%. Differences between groups 1 and 3 were significant, as were those between groups 1 and 2 (P < 0.05). Patients with mismatched perfusion defects had increased DTPA clearance compared with the control group and those with matched defects. CONCLUSIONS: Vascular occlusion may lead to impairment of the alveolar-capillary barrier and consequently an increase in the clearance of Tc-99m DTPA aerosol in embolized regions. Immediately after inhalation, Tc-99m DTPA imaging should be started in the projection where perfusion defects are best seen to avoid potential misinterpretation of pulmonary embolism.

Administration, Inhalation↗