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Biomedical subjects

M Ozkan

Publications and source records attributed to M Ozkan.

At least 37 records · Page 2Linked to original sources
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↗
PubMed2000

Single-photon emission computed tomographic myocardial perfusion imaging in patients with mitral valve prolapse.

The possibility of exercise-induced myocardial ischemia due to mitral valve prolapse (MVP) in the absence of coronary artery disease was evaluated with single-photon emission computed tomographic analysis using thallium-201 and technetium-99m sestamibi in 72 patients with MVP. Exercise electrocardiography was positive in 5 patients (8%), but single-photon emission computed tomography was found to be normal in all patients, and exercise-induced chest pain, electrocardiographic changes, and arrhythmias were found not to be related to myocardial ischemia in patients with MVP.

Adult↗
PubMed2000

Intravenous thrombolytic treatment of mechanical prosthetic valve thrombosis: a study using serial transesophageal echocardiography.

OBJECTIVE: We analyzed the results of intravenous thrombolytic treatment under transesophageal echocardiographic (TEE) guidance in prosthetic valve thrombosis. BACKGROUND: Thrombotic occlusion of prosthetic valves continues to be an uncommon but serious complication. Intravenous thrombolytic treatment has been proposed as an alternative to surgical intervention. METHODS: In a four-year period, 32 symptomatic patients with prosthetic valve related thrombosis underwent 54 thrombolytic treatment sessions for the treatment of 36 distinct episodes. All patients had low international normalized ratio values at the presentation. Transesophageal echocardiography was performed at baseline and repeated after each thrombolytic treatment session (total 98 TEE examinations). Streptokinase was used as the initial agent with a repeat dose given within 24 h when necessary. Recurrent thrombosis was treated either with tissue plasminogen activator or urokinase. RESULTS: The initial success after first dose was only 53% (17/32) but increased up to 88% (28/32) after repeated thrombolytic sessions upon documentation of suboptimal results on TEE examination (p < 0.01). In addition, four asymptomatic patients with large thrombi were also successfully treated with single infusion. The TEE characteristics of thrombus correlated with clinical presentation and response to lytics. Success was achieved with single lytic infusion in 40% of the obstructive thrombi as compared with 75% of the nonobstructive ones (p < 0.05). The success rates of lytic treatment were similar for mitral versus aortic valves, and for tilting disk versus bileaflet valves. Rapid (3 h) and slow (15 to 24 h) infusion of streptokinase resulted in similar success rates. However, major complications (three patients) occurred only in the rapid infusion group. CONCLUSION: In patients with prosthetic valve thrombosis, intravenous slow infusion thrombolysis given in discrete, successive sessions guided by serial TEE and transthoracic echocardiography can be achieved with a low risk of complications and a high rate of success.

Adult↗
PubMed2000

Conservative treatment of intra-articular fractures of the distal radius--factors affecting functional outcome.

One hundred and eleven intra-articular fractures of the distal radius in young adults that were conservatively treated were studied. At two years, 80% of fractures were rated as excellent or good by the modified Green and O'Brien scoring system. The rate of re-displacement within casts was 28%. Sixty five per cent of re-displaced fractures were treated with surgical fixation. Those re-displaced fractures treated with repeated manipulation had only 33% excellent or good result. Moreover, their initial alignment could not be preserved. Axial compression (>2 mm) and dorsal angulation (>15 degrees ) were directly related to worse functional outcome and diminished range of motion.

Adolescent↗
PubMed1999

Immunoadjuvant action of plasmid DNA in liposomes.

Bacterial DNA and oligodeoxynucleotides containing immunostimulatory sequences with a CpG motif stimulated a Th1 type response in vivo. The adjuvant action of a non-coding plasmid DNA derived from pRc/CMV HBS (encoding the S region of hepatitis B surface antigen, HBsAg) in mice was investigated. The role of methylation on the adjuvanticity of the plasmid as well as the effect of vaccine formulation employed on the outcome of antigen-specific humoral and cellular responses were also studied. The results demonstrated that plasmid DNA acted as a Th1 promoting adjuvant when mixed as such or co-entrapped in liposomes with a very low dose of antigen. However, the adjuvant activity was lost when separate liposome entrapped formulations of both the antigen and the plasmid DNA were mixed, indicating a necessity for the antigen and the plasmid DNA to contact the same APC for optimal immune activation. A decreased adjuvanticity of plasmid DNA upon methylation with HpaII methyltransferase was also demonstrated. A mechanism that may help partially explain the reduction in adjuvanticity after modification of C residues is also discussed.

Adjuvants, Immunologic↗
PubMed1998

Predictors of left atrial thrombus and spontaneous echo contrast in rheumatic valve disease before and after mitral valve replacement.

In this study we aimed to analyze, with reference to mitral regurgitation (MR), the incidence and predictors of left atrial (LA) thrombus and spontaneous echo contrast in patients with rheumatic valve disease before and after mitral valve replacement. The incidence of LA thrombus is known to be less in patients with MR. The impact of mitral valve replacement on this beneficial effect has not been studied in detail. The study included 169 consecutive patients (59 men and 110 women, average age 40 +/- 13 years) with rheumatic mitral valve disease who underwent transesophageal echocardiographic examination 1 to 3 days before and within 7 days (mean 4.0 +/- 1.3) after mitral valve replacement using mechanical prostheses in a single institution. The preoperative incidence of echocardiographic LA spontaneous echo contrast (SEC) was 1.1%, 30%, and 54%, and the incidence of thrombus was 1.1%, 13%, and 17% in the groups with MR, combined mitral stenosis + MR, and isolated mitral stenosis, respectively. In the MR group, SEC and thrombus incidence increased significantly after surgery. The independent predictors for postoperative thrombus development were atrial fibrillation, postoperative SEC, and preoperative thrombus. Thrombus recurred after surgery in 64% of 14 patients who had surgical thrombectomy. The presence of postoperative MR was associated with decreased risk of postoperative SEC and thrombus development. The interaction between MR and SEC and thrombus both before and after surgery provides further support for the protective effect of MR against LA thrombus formation.

Adult↗
PubMed1997

Subungual glomus tumours: a different approach to diagnosis and treatment.

Nine cases of subungual glomus tumour in which a transillumination test was used for diagnosis and a different operative technique was used to prevent postoperative nail deformity are described. The transillumination test is a new method for identifying a glomus tumour. With our surgical technique it is simple to approach a glomus tumour under the proximal nail bed and it produces a minimal defect.

Adult↗