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Biomedical subjects

M Ozkan

Publications and source records attributed to M Ozkan.

At least 19 recordsLinked to original sources
PubMed2003

Cardiopulmonary bypass as a cause of free radical-induced oxidative stress and enhanced blood-borne isoprostanes in humans.

Free radicals are believed to be involved in postsurgery-related complications. We studied whether cardiopulmonary bypass (CPB) operation has any immediate impact on the initiation of oxidative stress and inflammatory response by measuring isoprostanes and prostaglandin F2alpha during and 24 h following CPB. The levels of 8-iso-PGF2alpha (a major F2-isoprostane and biomarker of oxidative stress) and 15-keto-dihydro-PGF2alpha (a major metabolite of PGF2alpha and biomarker of inflammatory response) were measured in frequently collected plasma samples before, during, and up to 24 h postsurgery in 21 patients. 8-Iso-PGF2alpha levels significantly increased within 3 min (p <.0001) and continued until 50 min (p <.0001) during CPB. On the contrary, no significant increase of inflammatory response indicator, 15-keto-dihydro-PGF2alpha was found during and up to 24 h postoperatively. These findings establish an increased free radical-induced oxidative stress activity rather than inflammatory response after CPB.

Adult↗
PubMed2003

Urinary neopterin measurement as a non-invasive diagnostic method in pulmonary tuberculosis.

SETTING: Pulmonary department of a university hospital in Ankara, Turkey. OBJECTIVE: To investigate the usefulness of neopterin in pulmonary tuberculosis (PTB) as a rapid diagnostic tool. DESIGN: Neopterin concentrations in bronchoalveolar lavage fluid (BAL), serum and urine were measured in patients with PTB, with lung cancer and with pneumonia and in a healthy control group. RESULTS: In the BAL of PTB patients, serum and urine levels of neopterin were significantly higher than all the other groups (P < 0.001). Compared with the lung cancer group, PTB patients had higher neopterin in BAL and urine (P < 0.05). The PTB group had higher levels not only in BAL and urine, but also in serum, than the pneumonia group (P < 0.05). Compared with the pneumonia group and the healthy controls, neopterin levels in serum and urine were significantly higher in the lung cancer group (P < 0.05). In the PTB group, patients with moderately advanced PTB according to radiographic extent had higher levels of urine neopterin than patients with minimal disease (P = 0.01). CONCLUSION: Neopterin levels in BAL, serum and particularly in urine may reflect PTB activity before exact diagnosis of the disease by culture results, and correlates with radiological extent.

Adult↗
PubMed2002

Giant ancient schwannoma of the posterior mediastinum cytologically misdiagnosed as a malignant tumour. A case report.

We report a case of a 45-year old woman who was found to have a giant mediastinal tumour with radiological degenerative changes. She underwent thoracotomy to remove the mass, which was eventually diagnosed histologically as an ancient schwannoma, whereas cytological interpretation of the accompanying pleural fluid was malignant. Ancient schwannoma is a rare variant of schwannoma, histologically showing atypical features that may result in erroneous diagnosis of a malignant tumour. Clinical and radiological findings are important aids for further consideration of surgical removal of these potentially resectable tumours.

Female↗
PubMed2001

Alterations in exhaled gas profile during allergen-induced asthmatic response.

The source of exhaled carbon monoxide (CO) and the relationship to airway inflammation are not clear. If CO is produced by the inflamed airway, we hypothesized that inflammation induced by allergen challenge would increase exhaled CO of atopic asthmatics. Eight atopic asthmatics underwent whole lung allergen challenge. CO, nitric oxide (NO), oxygen, and carbon dioxide (CO(2)) were measured simultaneously in exhaled breath which was collected into Mylar balloons before (baseline), immediately after, and at subsequent times after allergen. NO was higher in asthmatics than control subjects at baseline, increased further in seven of the eight asthmatics after allergen, and was inversely correlated to specific conductance. In contrast, exhaled CO of asthmatics was not higher than that of control individuals at baseline, decreased immediately after allergen, and returned to baseline levels during the late asthmatic response. Thus, allergen-induced airway inflammation did not lead to increased exhaled CO in asthma.

Adult↗
PubMed2001

Indirect MR arthrography of the shoulder in detection of rotator cuff ruptures.

The aim of this study was to compare the efficacy of indirect MR arthrography images obtained following intravenous contrast injection and conventional MR imaging in the diagnosis of rotator cuff tears. Twenty-four patients with clinically suspected rotator cuff disease were examined. Conventional MR images and post-contrast indirect MR arthrography images were obtained. All images were evaluated in a blinded fashion by two musculoskeletal radiologist. Results were than analyzed depending on surgical output. The correlation coefficient (Spearman rank correlation test) and the kappa values for agreement between surgery and imaging techniques were calculated. The correlation coefficients between indirect MR arthrography and surgery for reader 1 and reader 2 were 0.9137 and 0.9773, respectively. Whereas the agreement between conventional MR imaging and surgery was moderate (n = 0.383-0.571), the agreement between indirect MR arthrography and surgery was excellent (n = 0.873-0.936). We suggest the use of indirect MR arthrography technique when conventional MR images are equivocal in diagnosis of rotator cuff disease.

Adolescent↗
PubMed2001

High levels of nitric oxide in individuals with pulmonary hypertension receiving epoprostenol therapy.

Lack of vasodilator substances, such as nitric oxide (NO), has been implicated in the development of pulmonary hypertension, but the pathogenesis of the disease remains speculative. We hypothesized that NO plays a role in the pathogenesis of primary pulmonary hypertension (PPH), and may serve as a sensitive and specific marker of disease progression and/or severity. To test this, exhaled NO and pulmonary artery pressure were measured in individuals with PPH and secondary pulmonary hypertension (SPH) on various therapies, including the potent vasodilator epoprostenol (prostacyclin), compared with healthy controls. NO in exhaled breath of individuals with PPH was lower than SPH or control (p<0.05). In contrast, exhaled NO of individuals with PPH or SPH receiving epoprostenol was strikingly higher than PPH or SPH individuals not receiving epoprostenol, or controls. Concomitant with higher NO levels, right ventricular systolic pressure of individuals significantly decreased with epoprostenol. Importantly, in paired measures of exhaled NO before and after epoprostenol, NO increased in all pulmonary hypertensive individuals 24 h after initiation of epoprostenol therapy (p<0.05). NO may be a useful noninvasive marker of pulmonary hypertension severity and response to prostacyclin therapy.

Adolescent↗
PubMed2001

Successful removal of a giant recurrent mediastinal liposarcoma involving both hemithoraces.

Primary liposarcomas of the mediastinum are unusual tumors. We report herein a case of a 52-year-old woman, who was found to have a mediastinal tumor involving both hemithoraces and radiologically showing non-resectable-invasive features to the adjacent vital structures. She had a history of left thoracotomy for mediastinal schwannoma 14 years previously. The patient underwent an exploratory thoracotomy following a preoperative misdiagnosis of an ancient schwannoma. Complete removal of the tumor was accomplished through a right posterolateral thoracotomy with a subsequent histological diagnosis of a recurrent low-grade liposarcoma. A resectable liposarcoma should be considered in the differential diagnosis of a mediastinal tumor, although radiologically, the tumor presents with invasive features.

Diagnostic Errors↗
PubMed2001

Characterization of 13 newly isolated strains of anaerobic, cellulolytic, thermophilic bacteria.

Characteristics of 13 newly isolated thermophilic, anaerobic, and cellulolytic strains were compared with previously described strains of Clostridium thermocellum: ATCC 27405 and JW20 (ATCC 31549). Colony morphology, antibiotic sensitivity, fermentation end-products, and cellulose degradation were documented. All 13 strains were sensitive to erythromycin (5 microg/ml) and chloramphenicol (25 microg/ml), and all strains but one were sensitive to kanamycin (20 microg/ml). Polymerase chain reaction (PCR) amplification using primers based on gene sequences from C. thermocellum ATCC 27405 was successful for all 13 strains in the case of the hydrogenase gene and 11 strains in the case of phosphotransacetylase/acetate kinase genes. Ten strains amplified a product of the expected size with primers developed to be specific for C. thermocellum 16SrRNA primers. Two of the 13 strains did not amplify any product with the PCR primers designed for the phosphotransacetylase/acetate kinase and 16SrRNA primers. A MboI-like GATC- recognizing restriction activity was present in all of the five strains examined. The results of this study have several positive implications with respect to future development of a transformation system for cellulolytic thermophiles.

Bacteria, Anaerobic↗
PubMed2001

Pulmonary artery thrombi detected by echocardiography in patients with pulmonary hypertension secondary to atrial septal defect.

This report presents three patients with severe pulmonary hypertension secondary to atrial septal defect associated with thrombus and spontaneous echo contrast within the pulmonary artery diagnosed by transthoracic and transoesophageal echocardiography. Clinical and echocardiographic features seem to suggest local thrombus formation within the pulmonary arteries as a direct consequence of pulmonary hypertension rather than venous thromboembolism.

Adult↗
PubMed2001

Location, size and morphological characteristics of left atrial thrombi as assessed by echocardiography in patients with rheumatic mitral valve disease.

AIMS: This study aimed to assess the use of transthoracic and transoesophageal echocardiography in diagnosing the thrombi located in the left atrium and/or left atrial appendage in patients with rheumatic mitral valve disease, and to investigate the characteristics of thrombi in comparison to intraoperative findings. METHODS AND RESULTS: The study group was comprised of 474 patients who underwent transthoracic and transoesophageal echocardiography prior to mitral valve surgery. Location, thickness and morphological characteristics of thrombi were determined by transoesophageal echocardiography. Intraoperative assessment disclosed left atrial thrombi in 105 patients. Thickness of thrombi < or = 1cm, and thrombi confined to left atrial appendage were associated with false-negative results by transthoracic echocardiography. However, diameter and morphological characteristics of thrombi, left atrial and left atrial appendage size, and the presence of the spontaneous echo contrast were not associated with the diagnosis of thrombi by transthoracic echocardiography. For overall left atrial thrombi, sensitivity and specificity of transthoracic echocardiography were 32%, and 94%, respectively. Sensitivity and specificity of transoesophageal echocardiography for thrombi in the left atrial appendage were 98%, and 98%, for thrombi in the main left atrial cavity were 81%, and 99%, and for thrombi located in both left atrium and appendage cavities were 100%, and 100%, respectively. CONCLUSION: In patients with rheumatic mitral valve disease, detection of left atrial thrombi by transthoracic echocardiography seems to be determined by thickness and location of thrombi. The multilobed structure of the left atrial appendage and artifacts over posterior wall of the left atrium may still prevent precise diagnosis even with transoesophageal echocardiography.

Adult↗
PubMed2001

[Hand injury caused by air bag trauma. Case report and review of the literature].

Although the airbag is designed to protect people from injury, it sometimes causes injuries. A case with open dislocation of the first carpometacarpal joint and fractures of the ulna and of several ribs due to an airbag is presented. The treatment is reported and the prevention of this injury is discussed with the literature reviewed.

Adult↗
PubMed2001

[Stay away from surgery: ecthyma contagiosum].

15 patients with Orf's disease were evaluated. Seven out of 15 patients (Group 1) were treated surgically because of different diagnoses. Seven patients who were misdiagnosed and treated surgically (Group 1), and eight patients (Group 2) were followed conservatively. The aim of this study is to compare the treatment period of the misdiagnosed surgically treated (Group 1) group and conservatively treated group (Group 2). Lesions were aggravated and delayed healing was observed in Group 1. Diagnosis of Orf disease may sometimes be difficult because of concominant bacterial superinfections and surgical trauma. Careful history and clinical findings point to the correct diagnosis. Contrary to other infections of the hand, surgery can cause further complications in this disease. Conservative treatment is the gold standard, even in complicated cases.

Adult↗
PubMed2001

Utility of ventilation and perfusion scan in the diagnosis of young military recruits with an incidental finding of hyperlucent lung.

Swyer-James-MacLeod syndrome (SJMS) is considered to be a relatively uncommon disease presenting with unilateral hyperlucent lung due to hypoplasia of a pulmonary artery and bronchiectasis of the affected lung. In this report, we describe the ventilation-perfusion (V/Q) scan findings of nine male recruits (aged 20-29 years, mean 24.4+/-2.96 years) with SJMS in whom the diagnosis was first established in adulthood. V/Q scan findings of all patients were compared with those on planar radiographs, pulmonary function studies, high resolution computed tomography (HRCT) and digital subtraction angiography (DSA). The ventilation (133Xe) and perfusion (99Tcm-macro-aggregated albumin) scans showed the characteristic pattern of a matched V/Q defect and marked air trapping on the washout phase on 133Xe scintigraphy. HRCT displayed hypodense lung with integrity of main airways, and markedly diminished vasculature on the affected side in all patients. A smaller pulmonary artery on the affected side with poor peripheral vasculature was observed with DSA in all patients. All patients had features of obstructive airway disease in varying degrees on pulmonary function studies. In contrast to other imaging methods, bronchiectasis as an etiological factor was displayed on HRCT. Some pulmonary areas, which were normal on HRCT and planar radiographs, showed air trapping on V/Q scan. Although a V/Q scan was more helpful in determining the extent of the disease and correlates well with conventional imaging methods, HRCT was the most valuable imaging method for the evaluation of aetiology in unilateral hyperlucent lung.

Adult↗
PubMed2001

High levels of exhaled nitric oxide (NO) and NO synthase III expression in lesional smooth muscle in lymphangioleiomyomatosis.

Smooth-muscle proliferation is the hallmark of lymphangioleiomyomatosis (LAM). Although little is known about the pathogenesis of LAM, nitric oxide (NO) is a key regulator of smooth-muscle proliferation. NO is linked to the pathogenesis of other lung diseases such as asthma, in part by the finding of higher-than-normal levels of exhaled NO. If NO were involved in the abnormal smooth-muscle proliferation in LAM, we reasoned that exhaled NO from individuals with LAM would also differ from that of healthy control subjects. To evaluate this hypothesis, we studied exhaled NO in individuals with LAM in comparison with healthy and asthmatic women using a chemiluminescent NO analyzer. Women with LAM had higher exhaled NO than did healthy women but lower than asthmatic women (NO [parts per billion] median (25 to 75%): LAM 8 [7 to 15] [n = 28], control 6 [5 to 8] [n = 21], asthma 14 [8 to 25] [n = 22]; Kruskal-Wallis P < 0.001). Immunohistochemical studies on formalin-fixed, paraffin-embedded sections of surgical and autopsy material from lungs of individuals with LAM showed diffuse NO synthase III (NOSIII) expression in the lesional smooth muscle of LAM similar to that in the vascular endothelium. NOSIII expression was limited to the vascular endothelium and bronchial smooth muscle in healthy control lungs. The increased NO and the presence of NOSIII expression in lesional smooth muscle warrants further study into the potential role for NO in the pathogenesis of LAM.

Adult↗
PubMed2001

Effect of cardiopulmonary bypass on plasma levels of lipoprotein (a) in hypercholesterolemic patients.

Increments of lipoprotein (a) (Lp (a)) concentration during cardiopulmonary bypass (CPB) have not been justified in the literature yet. We have investigated whether Lp (a) levels remain constant or increase during CPB and if high plasma levels of low density lipoprotein (LDL; containing apolipoprotein (apo) B) in hypercholesterolemic patients affect the assembly of Lp (a) (containing apoB: Apo (a)). In this study, the change in plasma lipid and lipoprotein levels of 40 patients with hypercholesterolemia and 40 patients who have normal cholesterol values were determined and compared during CPB, and in the postoperative early stage. In our study, lipid and lipoproteins, except Lp (a), showed a falling trend and paradoxically, Lp (a) statistically showed a significant rising trend, like the acute phase reactant in two groups (p=0.011 for LDL, p=0.016 for high density lipoprotein (HDL) and p<0.001 for the others, in 80 patients). Concentrations of Lp (a) in plasma increased more sharply in the hypercholesterolemic group than the normocholesterolemic group during CPB. This difference was significant at the 60th minute of cardiopulmonary bypass with a nonparametric test (p<0.05 Mann-Whitney U test). High density lipoprotein values showed more decline in the hypercholesterolemic group patients than in the normocholesterolemic group patients (p<0.05). In conclusion, lipoprotein (a) levels increased more pronounced in patients with hypercholesterolemia during CPB. On the other hand, high LDL levels in hypercholesterolemic patients accelerated Lp(a)formation in the acute phase.

Acute-Phase Proteins↗
PubMed2001

Drug-induced lung disease.

Drug-induced lung disease is a major source of iatrogenic injury. We review the various drugs known to induce injury and the various patterns of injury seen.

Drug-Related Side Effects and Adverse Reactions↗