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Featured researches published by Ünsal Özgen.


Pediatric Hematology and Oncology | 2003

Malignant Melanoma of the Soft Parts Showing Calciphylaxis

Nurettin Onur Kutlu; Nasuhi Engin Aydin; Mehmet Aslan; Taner Bulut; Ünsal Özgen

Calciphylaxis is a poorly understood and highly morbid syndrome of vascular calcification and skin necrosis. Hypercalcemia, hyperphosphatemia, and secondary hyperparathyroidism are the factors implicated in the pathogenesis of calciphylaxis, which is generally identified in patients with hyperparathyroidism secondary to end-stage renal disease. It has also been observed in primary hyperparathyroidism, end-stage liver disease, and rheumatoid arthritis, in the absence of renal disease. There are few case reports of calciphylaxis occurring in hypercalcemia of malignancy. An unusual case is reported of calciphylaxis associated with malignant melanoma of the soft parts in the absence of renal or parathyroid disease. This is the first reported case of this soft tissue sarcoma showing calciphylactic changes.


Leukemia | 2000

Further elucidation of mechanism of resistance to vincristine in myeloid cells: role of hypochlorous acid in degradation of vincristine by myeloperoxidase

Ünsal Özgen; Süreyya Savaşan; Mark Stout; Steven Buck; Yaddanapudi Ravindranath

Inherent resistance of myeloblasts to vincristine (VCR) has been related to the activity of myeloperoxidase (MPO) which can degrade VCR in the presence of hydrogen peroxide (H2O2). We investigated the relationship between VCR degradation and hypochlorous acid (HOCl) generation from the reaction of H2O2 with chlorine (Cl) as catalyzed by MPO. A cell-free system, three human leukemia cell lines (CEM/CCRF, HL-60, U937) and 15 bone marrow samples from children with acute myeloid leukemia (AML) were studied. VCR cytotoxicity was evaluated by MTT assay and by quantitative measurement of apoptosis. In vitro levels of VCR in cell-free systems were measured by high performance liquid chromatography (HPLC), and intracellular HOCl levels by oxidation of 5-thio-2-nitrobenzoic acid with the accompanying decrease in the absorbency at 412 nm. VCR was degraded by increasing concentrations of HOCl in cell-free systems and this activity was inhibited by taurine, which is known to block HOCl activity. This finding was confirmed by the VCR cytotoxicity studies on cell lines. The HOCl-producing myeloblasts from patients were resistant to VCR. In five samples out of eight HOCl was also detected extracellularly. These results suggest that oxidation by HOCl may be the final step in VCR degradation catalyzed by MPO through its action on intracellular H2O2 and Cl.


Pediatric Radiology | 2006

Neutropenic enterocolitis (typhlitis) associated with infectious mononucleosis

Ahmet Sigirci; Aysehan Akinci; Ünsal Özgen; Metehan Özen

Neutropenic enterocolitis (typhlitis) is an unusual acute complication of neutropenia, most often associated with leukaemia and lymphoma and characterized by segmental caecal and ascending colonic ulceration that may progress to necrosis, perforation, and septicaemia. We present a unique case of an 8-year-old girl with recently diagnosed infectious mononucleosis having findings consistent with typhlitis on abdominal CT.


Pediatric Hematology and Oncology | 2004

ANALYSIS OF PEDIATRIC THROMBOTIC PATIENTS IN TURKEY

Hale Ören; Omer Devecioglu; Sabri Kemahli; Canan Vergin; Adalet Meral; Duran Canatan; Hayri B. Toksoy; Inci Yildiz; Emin Kürekci; Ünsal Özgen; Haldun Öniz; Aytemiz Gurgey

This study analyzes the data of thrombotic children who were followed up in different pediatric referral centers of Turkey, to obtain more general data on the diagnosis, risk factors, management, and outcome of thrombosis in Turkish children. A simple two-page questionnaire was distributed among contact people from each center to standardize data collection. Thirteen pediatric referral centers responded to the invitation and the total number of cases was 271. All children were diagnosed with thromboembolic disease between January 1995 and October 2001. Median age at time of first thrombotic event was 7.0 years. Of the children 4% of the cases were neonates, 12% were infants less than 1 year old, and 17% were adolescents. Thromboembolic event was mostly located in the cerebral vascular system (32%), deep venous system of the limbs, femoral and iliac veins (24%), portal veins (10%), and intracardiac region (9%). Acquired risk factors were present in 86% of the children. Infection was the most common underlying risk factor. Inherited risk factors were present in 30% of the children. FVL was the most common inherited risk factor. Acquired and inherited risk factors were present simultaneously in 19% of the patients. Eleven children had a history of familial thrombosis. Due to the local treatment preferences, the treatment of the children varied greatly. Outcome of the 142 patients (52%) was reported: 88 (62%) patients had complete resolution, 47 (33%) had complications, 12 (9%) had recurrent thrombosis, and 34 (24%) died. Three children (2.1%) died as a direct consequence of their thromboembolic disease. The significant morbidity and mortality found in this study supports the need for multicentric prospective clinical trials to obtain more generalizable data on management and outcome of thrombosis in Turkish children.


Pediatrics International | 2013

Prevalence of Demodex folliculorum and Demodex brevis in childhood malnutrition and malignancy.

Sadık Kaya; Mukadder Ayşe Selimoğlu; Özlem Aycan Kaya; Ünsal Özgen

Hair follicle mites, Demodex folliculorum and Demodex brevis, are known to accompany immune‐deficiency states, however no study so far has investigated their presence in malnutrition. In this study we aimed to determine the prevalence of those mites in childhood malnutrition, malignancy and risk factors.


Transfusion and Apheresis Science | 2013

Therapeutic plasma-exchange in hematologic disease: Results from a single center in Eastern Anatolia

Mehmet Ali Erkurt; Irfan Kuku; Emin Kaya; Ünsal Özgen; Ilhami Berber; Mustafa Koroglu; Mustafa Ozgul

Therapeutic plasma-exchange (TPE) is used as primary and adjunctive therapy in treatment of several hematologic diseases. We retrospectively evaluated the results of TPE in hematologic diseases during 2008-2012. A total of 301 TPE procedures were performed in 44 patients (19 male and 25 female, with mean age of 50.6±15years). Fifteen of 44 patients had thrombotic thrombocytopenic purpura (TTP), 14 patients had HELLP syndrome (Hemolysis Elevated Liver enzymes, Low Platelet count), 10 patients had multiple myeloma-hyperviscosity and the rest five patients had snake bite. Fresh frozen plasma (FFP) was used as replacement fluid. Complete response (CR) was achieved on 13 patients (87%) in primarily TTP. CR was achieved in all other three diseases. Total complications were detected in 8.1% of the TPE procedures. Adverse events (AEs), were seen in 5.4% of all procedures. None of the patients died from any complication. AE occurred in 4% (Grade-I), 1% (Grade-II), and 0.3% (Grade-III) of the procedures. The most common AE were nausea/vomiting, hypotension, pruritus and abdominal pain. TPE is effectively and safely carried out in our center in hematologic diseases.


Pediatric Hematology and Oncology | 2000

Is AML1/ETO gene expression a good prognostic factor in pediatric acute myeloblastic leukemia?

Nazan Sarper; Ugur Ozbek; Leyla Agaoglu; Ünsal Özgen; Ertuğrul Eryilmaz; Nevin Yalman; Sema Anak; Omer Devecioglu; Gunduz Gedikoglu

To assess the clinical significance of AML1/ETO gene detected by nested reverse transcriptase polymerase chain reaction, the outcome of 7 patients with acute myeloblastic leukemia between 3 and 14 years of age were presented. All patients had complete remission (CR) at the end of induction (AMLMRC 10 protocol) and 4 underwent unpurged autologous, 2 allogeneic (from matced siblings) non-T-cell-depleted bone marrow transplantations (BMT) in first CR. One patient died due to allogeneic BMT-related complications, and 4 patients relapsed at 13, 17, 18, and 26 months. Only one patient achieved second CR. All relapsed patients died between 18 and 36 months with resistant disease (n = 3) or infection during salvage chemotherapy (n = 1). Two patients who had autologous BMT are alive and disease free at 44 and 50 months. Although statistical significance could not be shown, event-free survival and overall survival rates of AML1/ETO-positive patients (28.57 and 28.57% , respectively) at 3.5 years were even lower than those of AML1/ETO-negative patients. The results confirm some previous reports that AML1/ETO gene in children and adolescents is not a favorable prognostic factor.


Dicle Tıp Dergisi | 2009

Sünnet öncesi uygulanan lokal prilokaine baglı methemoglobinemi olgusu

Yılmaz Tabel; Ayşe Sandikkaya; Serdal Güngör; Ünsal Özgen

The articles about various pneumoconiosis in dental technicians who work in inconvenient conditions have been increasing in recent years. Exposure to dust and fume that occur during the dental procedure may play role in pneumoconiosis of dental technicians. A 53 years old male patient conveyed that he has worked in dental prosthesis procedures for 22 years (1968-1990).Environmental asbestosis was not established in the history of the case but there were calcified pleural plaques in the chest x-ray graphy.There were appearance of calcific asbest plaques in many section of thorax CT.A case of pneumoconiosis in dental technician who work in unadequate preventive conditions was reported in this paper. Probably ,exposure to the asbest fibers that occurs during the procedure of dental prosthesis were the main reason for developing calcific pleural lesions.The aim of this study was to investigate the efficacy of occlusion treatment on different age group patients with anisometropic amblyopia. Occlusion treatment was applied to 34 patients, 15 preschool children (age between 4-6 years), and 19 school age children (7-11 years). Daily duration of occlusion was minimum 6 hours. Best corrected visual acuity of patients was measured initially, at the end of 1st, 3rd and 6th months. Data belonging to amblyopia groups was compared with one another and with the controls. Initial visual acuity of two amblyopia groups were similar, however there was a significant difference between the amblyopia groups and the controls (PChest pain is a frequently encountered problem in childhood. In this study we aimed to asses the relationship between exertional chest pain and asthma by using the peek expiratory flow rate measurements. For this study, 64 otherwise healthy children with chest pain (chest pain group), 9-16 years of age (mean 11.9) and 58 healthy (control group), 8-11 years (mean 11.5) were compared with the use of peak flow-meter. Ages, weights, heights, systolic-diastolic blood pressures, pulses recorded. Preexertional and postexertional peak flow measurements (PEFR) at 2, 5 and 10 minutes determined. There was a decrease more than 15% in PEFR measures in 7 (10.9%) of chest pain group and in 1 (1.7%) of control group children (p


Childs Nervous System | 2017

Hodgkin’s lymphoma associated with paraneoplastic cerebellar degeneration in children: a case report and review of the literature

Serdal Güngör; Betul Kilic; Müjgan Arslan; Ünsal Özgen; Josep Dalmau

Paraneoplastic cerebellar degeneration (PCD) can occur severely and appear as subacute cerebellar syndrome. PCD may be associated with small cell lung cancer, adenocarcinoma, breast cancer, ovarian carcinoma, and Hodgkin’s lymphoma. An 11-year-old male was admitted with acute cerebellar ataxia, dysarthria, and diplopia. Mediastinal conglomerated lymph nodes were depicted in a chest computed tomography (CT) examination, and diagnosis of stage IV Hodgkin’s lymphoma was obtained after a lymph node biopsy. The antibodies against Purkinje cells (anti-Tr antibody) were positive immunohistochemically. Thus, paraneoplastic cerebellar degeneration depending on Hodgkin’s disease was diagnosed. Despite the completion of chemotherapy, neurological recovery was not observed in the patient and plasmapheresis with immunoadsorption, and intravenous immunoglobulin (IVIG) was performed. Truncal ataxia, gait disturbance, and tremors decreased. Consequently, we thought that plasmapheresis with the immunoadsorption method and IVIG therapy might be a treatment option for cerebellar ataxia caused by a mechanism of immune ancestry.


Acta parasitologica Turcica | 2013

Evaluation of the intestinal parasitic infections in children patients with cancer

Fatih Durak; Metin Dogan; Metin Atambay; Ünsal Özgen; Metehan Özen

OBJECTIVE We aimed to determine the prevalence and type of the intestinal parasites in healthy, cancer and survivor children after cancer therapy, and to evaluate whether there are any differences in incidence and types of parasites during their neutropenic period. METHODS Three different patient groups were formed. Group I and Group II were immune deficient patients with hematologic malignancy or solid tumors, and Group I were receiving intensive chemotherapy and had absolute neutrophil count less than 1000/mm³. Group II were receiving maintenance chemotherapy and had normal absolute neutrophil counts. One hundred and seventy two patients, who did not receive chronic immune suppressant treatment and who did not have immune deficiency were chosen among the patients admitted to pediatric hematology outpatient clinic. Parasitic evaluation of stools was performed on three consequtive days. RESULTS Prevalence of parasite in Group I patients was significantly higher than other groups. The most commonly detected parasite in all groups was Giardia intestinalis. The presence of parasite in patients with absolute neutrophil counts below 1000/mm³ was found to be significantly higher than in patients with absolute neutrophil counts above 1000/mm³. CONCLUSION Parasitic infections should not be ignored when these types of patients present with infection findings.

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