Senay Öztop
Ege University
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Featured researches published by Senay Öztop.
Journal of Tropical Pediatrics | 1996
Nişli G; Canan Vergin; Senay Öztop; Nazan Çetingül
It has been shown that high doses of human recombinant erythropoietin (r epo) increase haemoglobin levels by augmentation of F-cells, and Hb-F production in animal models and in human trials. In this study, r epo was used in patients with beta thalassemia intermedia. Our purpose was to improve haemoglobin levels by at least 2 g and maintain an average level between 10 and 12 g/dl. Ten patients aged 6-29 years (mean 14 +/- 7.6 years) with thalassemia intermedia were treated with r epo. It was given subcutaneously in rising doses from 500 to 1000 U/kg three times weekly for 3 months. During r epo therapy eight cases (80 per cent) showed an increase in haemoglobin, haematocrit, and reticulocyte levels, and an increase of at least 2 g of haemoglobin was obtained. Blood transfusion was not needed during the study except in one case. Five cases (50 per cent) improved life quality with therapy. Hb levels of all patients returned to baseline values over 1 or 2 months after r epo was discontinued. There was no significant change in absolute Hb-F, F-cells, and ferritin levels during treatment. Generally, the drug was well tolerated. No patient had hypertension. Recombinant erythropoietin seems to be an effective treatment for anaemia of beta-thalassemia intermedia, but longer term randomized trials are needed especially in patients with beta thalassemia major.
Pediatric Hematology and Oncology | 1996
Necil Kutukculer; Onur Kutlu; Nişli G; Senay Öztop; Nazan Çetingül; Suat Caglayan
Neutrophil chemotaxis and random migration were evaluated in 21 patients with thalassemia major and 21 healthy controls by a filter technique (Boyden chamber). Chemotactic and random migrations in patient group were found to be defective, which may partially account for the increased susceptibility to infection occasionally observed in these patients. The effects of serum ferritin levels, transferrin saturations that show iron overload, total count of blood transfusions for chronic immunostimulation, desferrioxamine therapy, and splenectomy on these neutrophil functions were examined in thalassemic patients in order to determine whether they are responsible for these defective functions because the mechanism of abnormal neutrophil chemotaxis and random mobility in thalassemic patients is not still clear.
Pediatric Hematology and Oncology | 1997
Nişli G; Yesim Aydinok; Senay Öztop; Nazan Çetingül
Serum erythropoietin (EPO) levels were determined by radioimmunoassay in 37 beta-thalassemia patients, the phenotype being thalassemia major (TM) in 30 and thalassemia intermedia (TI) in 7. The control group consisted of 37 healthy children. The mean serum EPO levels were significantly higher in patients with both TM (215.1 +/- 144.5) and TI (53.8 +/- 40.2) compared with the control group (9.3 +/- 4.6). Although the mean hemoglobin (Hb) concentrations in the patients with TM and TI were similar (8.6 +/- 0.9 and 8.7 +/- 1.1, respectively), the mean serum EPO level was significantly higher in TM patients than the patients with TI (P < .01). This finding may indicate that some other factors contributing to the metabolic adaptation to low oxygen concentration or improvement of the tissue oxygenation are as effective as the Hb concentration in EPO production. It is also suggestive of the fact that some amount of tissue hypoxia cannot be prevented in spite of polytransfusion regimens in TM patients. Serum EPO levels of TM patients were not found to be age related or correlated with the mean pretransfusional Hb levels. In the TM patients, the serum EPO concentration was not consistently correlated with clinical signs of erythropoietic activity. This may be indicative of personal differences with respect to the sensitivities of erythroid precursors to the increasing EPO levels in TM patients.
Pediatric Hematology and Oncology | 1999
Nazan Çetingül; Yesim Aydinok; Mehmet Kantar; Haldun Öniz; Osman Yalman; Serpil Erermis; Neşe Çelebisoy; Önder Akyürekli; Senay Öztop; Nişli G
The neurotoxicity of either systemic chemotherapy or central nervous system prophylaxis was studied in 19 children treated for acute lymphoblastic leukemia (ALL). They had completed ALL therapy at least a year before and survived more than 5 years after diagnosis. The duration between age at diagnosis and age at investigation was 8.6 +/- 2.7 years (5-15 years). Neuropsychologic tests, cranial magnetic resonance imaging (MRI), and evoked potentials (EP) were studied. Seventeen healthy siblings were taken as a control group. Emotional evaluation was done using the childhood depression inventory and Beck depression inventory. Cognitive functions were evaluated using Wechslers Intelligence Scale for Children-Revised (WISC-R) or the Wechslers Adult Intelligence Scale-Revised (WAIS-R) tests, which were adapted to Turkish children. Performance and total IQ scores (94.0 +/- 16.8 and 92.2 +/- 16.5) were significantly low as compared to the control group (112.1 +/- 18.9 and 105.4 +/- 14.2) (p = .007 and p = .02). Abnormal MRI findings were found in 33.3% (6/18). Three out of 18 patients (16.6%) had abnormal auditory while 5 out of 17 patients (29.5%) displayed abnormal visual EPs. Abnormal findings in MRI, cognitive examination, and electrophysiologic testing were not associated with age at diagnosis, radiotherapy doses, intermediate/high-dose systemic methotrexate administration or central nervous system involvement. But more patients must be studied to demonstrate discrete outcomes of neurotoxicity in long-term survivors of childhood leukemia.
Pediatric Hematology and Oncology | 1997
Nişli G; Yesim Aydinok; Senay Öztop; Nazan Çetingül; Sema Aydogdu; Osman Yalman
Prophylaxis has been practiced for many years in Europe and is gaining acceptance worldwide with current viral inactivation procedures. Unfortunately, the high cost of prophylaxis is currently the major obstacle to its implementation in developing countries such as Turkey. The aim of this controlled preliminary study is to evaluate the efficacy, safety, and feasibility of prophylaxis. Seven boys aged 1.5-7 years (5.0 +/- 1.8), who had severe hemophilia (six A, one B) received 20-50 IU/kg factor twice weekly and were followed up for 6-24 months (14.5 +/- 6.6). Intermediate concentrates have been used in hemophilia A and ultrapure product for hemophilia B. The data obtained for the same group of patients before prophylaxis were used as a control group. Another control group was selected in another group of 10 hemophiliacs, mean age 12.5, and received treatment on demand. During prophylactic treatment, the episodes of bleeding were decreased (from 10.5 +/- 3.2 to 4.5 +/- 3.6). Orthopedic and radiologic joint scores were stable (from 0 to 1 and from 1.1 +/- 1.2 to 1.0 +/- 1.5). The patients spent significantly fewer days in the hospital (from 18 +/- 12 to 0.7 +/- 0.6). None of the patients was infected with hepatitis A, hepatitis B, or human immunodeficiency virus. One patient was seroconverted with anti-hepatitis C virus in the third month of prophylaxis. Mean consumption of concentrates for prophylaxis was 3489 +/- 960 IU/kg per year compared with 2073 +/- 1302 in conventional therapy. Prophylaxis was superior to treatment on demand even when given in a twice-weekly period with intermediate concentrates. In Third World countries, prophylaxis should be tried at least in selected severely hemophilic children in order to prevent disabilities.
Journal of Tropical Pediatrics | 1997
Yesim Aydinok; Senay Öztop; Nişli G
Although the beta (beta) thalassaemia carrier frequency in Turkey was stated to be 2 per cent, the prevalence rate varies widely in different regions and there is limited data confirming the disorder in Aegean region. This prevalence study was planned to determine frequency of beta thalassaemia trait in the Aegean region among 1124 high school students, between 13 and 18 years old, who were selected as target population. Sensitivity of mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) in prediction of beta thalassaemia trait were evaluated. Venous blood samples were obtained for haemoglobin electrophoresis, HbA2 and HbF, serum iron and total iron binding capacity from students in whom the levels of haemoglobin (Hb), haemotocrite (Hct), MCV, or MCH, were low compared to normal values. The prevalence of beta thalassaemia trait in Aegean region was 3 per cent. Sensitivity of MCV and MCH for determining beta thalassaemia trait were 100 and 96 per cent, respectively.
Indian Journal of Pediatrics | 1997
Canan Vergin; Necil Kutukculer; Nazan Çetingül; Nişli G; Suat Caglayan; Senay Öztop
Serum IgG, IgM, IgA, IgG subclasses (IgG1, G2, G3, G4), isohemagglutinins and complement-3 concentrations were measured in 23 beta-thalassemic patients suffering from recurrent infections. No significant abnormalities were found in these humoral immunity investigations, both in splenectomized and non-splenectomized patients. On the other hand, iron overload or repeated blood transfusions were not found to down-regulate the humoral immune system of thalassemic patients.
Pediatric Hematology and Oncology | 1997
Nişli G; Yesim Aydinok; Senay Öztop; Nazan Çetingül
Beta (beta) globin gene analysis was performed in 54 homozygous beta-thalassemia patients followed up in the Pediatric Hematology Department of Medical School of Ege University. The spectrum of beta-thalassemia alleles and their effect on clinical severity of disease were investigated. Twelve different mutations were determined in our patients. The six most frequent alleles, IVSI-110 (G-A), IVSI-6 (T-C), IVSI-I (G-A), IVSII-745 (C-G), Cd39 (C-T), and FSC8, account for 80.6% of all the disease genes. Eleven percent of the chromosomes could not be identified with the probes used in this study. In 38 patients both of whose beta-thalassemia alleles were identified, the beta-thalassemia alleles were found to be the major determinant of the clinical severity of disease. The clinical progress of disease was also closely related to the degree of iron overload.
Journal of Tropical Pediatrics | 1996
Nazan Çetingül; Canan Vergin; Senay Öztop; Nişli G; Sema Aydogdu; Tijen Özacar; Altinay Bilgic; Gül Yüce; Rasit Vural Yagci
We have evaluated the efficacy of treatment with recombinant Interferon-2b (IFN-2b) in 12 children with cancer who developed chronic hepatitis-B infection. Seven of them had lymphoblastic leukaemia and others had solid tumours. Seven cases were male. Mean age was 10.5 years with a range of 5-16 years. Chronic Hepatitis B was diagnosed biochemically, serologically and histopathologically. They were HBsAg(+), HBV-DNA(+), and HCV(-), HIV(-). Seven cases were HBeAg(+) and two of them were anti-Delta IgG(+). Liver biopsy revealed chronic active hepatitis in six cases and persistent hepatitis in three cases. IFN was given at the dose of 5 MU/m2 three times a week, subcutaneously for 6 months. It was well tolerated. After IFN therapy, ALT levels returned to normal in seven cases. All cases were still HBsAg(+). Four of them seroconverted to anti-HBe antibody. Loss of serum HBV-DNA in three cases, but 11 cases showed a marked decrease after IFN. The control liver biopsies showed that histopathological activity index was diminished in five cases. Other 16 patients, serving as control, received no therapy. Five of them were leukaemia and others were solid tumours. Twelve cases were male. Mean age was 9.3 years with a range of 4-19 years. After 6 months, only one patient lost HBV-DNA and three of them seroconverted to anti-HBe with normalization of ALT values. In our study, IFN treatment favourably influenced the progress of chronic hepatitis B in children with cancer.
Pediatrics International | 1994
Nazan Çetingül; Erdal Yener; Senay Öztop; Nişli G; Saliha Soydan
Myelofibrosis with myeloid metaplasia, or agnogenic myeloid metaplasia (AMM) is a chronic myeloproliferative disorder characterized by fibrosis of the bone marrow accompanied by aniso‐ and poikilocytosis, leukoerythroblastosis and hepatosplenomegaly with extramedullary hematopoiesis. Agnogenic myeloid metaplasia is very rare in children. In this report, two cases of AMM in whom the onset of the illness were at 3 and 12 months of age, are presented. Both had severe anemia, hepatosplenomegaly and bone marrow fibrosis. Lymph node biopsy of the first patient and liver biopsy of the second revealed extramedullary hematopoiesis. They were treated with an intravenous high dose of methylprednisolone (daily 30 mg/kg for 3 days, 20 mg/kg for 4 days, 10 mg/kg for 1 week, 5 mg/kg for 1 week). A complete improvement of hematological and clinical findings was observed.