Biomedical subjects

Hamza Okur

Publications and source records attributed to Hamza Okur.

10 recordsLinked to original sources

PubMed2008

Congenital dysgranulopoietic neutropenia.

We investigated a 15-year-old female with congenital dysgranulopoietic neutropenia (CDN) and her non-neutropenic mother who had recurrent stomatitis. In both patients, cells of the neutrophilic, eosinophilic, monocytic, megakaryocytic, and basophilic series were dysmorphic. Plasmacytoid lymphocytes and mild megaloblastic erythroid precursors were present. Bleeding times of both patients were prolonged. The mother had a secondary aggregation defect; the number of the plasmacytoid lymphocytes, dense granules of platelets, and dysmorphic neutrophils, neutrophil chemotaxis, and myeloperoxidase content fluctuated according to the presence or not of aphthae. The daughter's karyotype revealed 46,XX/46,XX, t(1;8). No ELA2 or G-CSFR mutation was detected. These findings support stem cell involvement in CDN.

Adolescent↗

PubMed2005

Effect of short course high dose methylprednisolone on endothelin-1 and nitric oxide in children with acute lymphoblastic leukemia: a preliminary study.

We have investigated serum endothelin-1 (ET) and nitric oxide (NO) levels before and after a short course of high dose methylprednisolone (HDMP) in children with acute lymphoblastic leukemia (ALL) as an indicator of vasoconstrictor and vasodilator properties of endothelium. Nineteen children with ALL (aged 13-180 months; 5 girls and 14 boys) and 25 healthy children were included in the present study. The children with ALL were given HDMP (20 mg kg 1 day 1) alone for the first 5 days. Serum ET and NO levels were analysed before and after a short course of high dose methylprednisolone. Before treatment, serum ET levels (median 7.6 pg ml 1) of the patients were lower than the healthy controls (13.0 pg ml 1) (p < 0.05), and it rose to similar levels (13.0 pg ml 1) following therapy as in the controls. Nitric oxide levels (7.0 micromol) of the patients were insignificantly higher than the healthy controls (3.9 micromol) and did not differ after treatment (7.0 micromol) (p > 0.05). In conclusion, the elevation of ET to normal level following treatment suggests that a short course of high dose of methylprednisolone improve the endothelial dysfunction caused by acute leukemia.

Adolescent↗

PubMed2005

Lymphocyte subsets, TNF alpha and interleukin-4 levels in treated and untreated subacute sclerosing panencephalitis patients.

Immunologic studies in relation to clinical status might help to understand the pathogenesis of subacute sclerosing panencephalitis (SSPE) and the effect of treatment. We measured lymphocyte subsets and intracellular TNFalpha and interleukin-4 levels in peripheral blood in SSPE patients. Patients had elevated percentages of CD8+ cells compared to age-matched control children. Rapidly progressive course was associated with increased CD4+ cells. Treatment with interferons and inosiplex altered the percentage of CD3+, CD4+ and CD19+ cells. TNFalpha and interleukin-4 levels had no correlation with course or treatment. The proportions of lymphocyte subsets appear to have a role in the evolution or manifestations of SSPE, if not in the pathogenesis.

Adolescent↗

PubMed2005

Prothrombin G20210A mutation in Turkish children with thrombosis and the frequency of prothrombin C20209T.

The prothrombin G20210A mutation has been described as the second most common genetic risk factor in thrombotic patients. Recently a new prothrombin gene variant namely prothrombin C20209T has also been found to be associated with thrombosis. In the present study the frequency of these two thrombin variants have been searched in two different groups. Group 1: A total of 377 children with thrombosis were analyzed during 7 years between January 1997 and 2004 and screened for prothrombin G20210A mutation. Twenty-four of 387 children (6.3%) with thrombosis were diagnosed as having PT G20210A mutation. The mean age of the patients was 6.1 years (median: 6 years, range: 4 months to 17 years, 15 male, 9 female). Six of 24 children were below 2 years of age (25%). Fifteen of 24 children (62.5%) had arterial thrombosis, most of whom (93.3%) had cerebral infarct. Group 2: The prothrombin C20209T variant has been analyzed in 200 thrombotic patients and in 200 healthy subjects. None of the thrombotic patients and healthy individuals carried the prothrombin C20209T variant. In conclusion, arterial thrombosis as the cerebral infarct is the most prominent type of thrombosis in children with prothrombin G20210A mutation. It seems that the prothrombin C20209T variant is not an important risk factor for the population studied.

Adolescent↗

PubMed2005

Effects of prophylactic thyroid hormone replacement in euthyroid Hashimoto's thyroiditis.

Hashimoto's thyroiditis is the most frequent autoimmune thyroid disease. L-thyroxine therapy can reduce the incidence and alleviate the symptoms of this disease. The aim of this study was to evaluate the effects of prophylactic L-thyroxine treatment on clinical and laboratory findings of patients who were euthyroid at the time of diagnosis. Thirty-three patients who had diagnosis of euthyroid Hashimoto's thyroiditis were randomized to two groups, one group received prophylactic L-thyroxine treatment and the other was followed-up without treatment. Initial thyroid function tests, autoantibodies, ultrasonography, fine needle aspiration biopsy and peripheral blood lymphocyte subsets were similar in the two study groups. After 15 months of L-thyroxine treatment, there was a significant increase in free T4 and a significant decrease in TSH and anti-thyroglobulin antibody anti-thyroid peroxidase antibody levels. CD8+ cell counts increased in both groups, CD4/CD8 levels decreased significantly because of the increase in CD8+ cell count levels. Though there was no change in cytological findings, ultrasonography showed a decrease in thyroid volume in L-thyroxine receiving patients whereas an increase was detected in patients who were followed without treatment. In conclusion, prophylactic thyroid hormone therapy can be used in patients with Hashimoto's thyroiditis even if they are euthyroid.

Adult↗

PubMed2005

Neutrophil CD64 expression in Behçet's disease.

OBJECTIVE: Hyperfunction of neutrophils is a characteristic finding in Behçet's disease (BD). Microbial agents have been proposed as causative agents in the disease flares. Fc gamma receptor 1 (CD64) is not normally expressed by neutrophils of healthy individuals, but is upregulated by these cells in response to microbial wall components and proinflammatory cytokines. The degree of polymorphonuclear leukocyte (PMN) CD64 expression is different in autoimmune diseases and systemic infectious diseases. We investigated PMN CD64 expression in patients with BD. METHODS: Thirty-seven patients with active BD (M/F: 18/19, mean age: 34.4 +/- 9.7 yrs), 35 patients with inactive BD (M/F: 11/24, mean age: 35.9 +/- 11.6 yrs), 27 patients with culture proven infections (M/F: 19/8, mean age: 54.4 +/- 15.2 yrs), 31 healthy controls (M/F: 14/17, mean age: 37.7 +/- 8.7 yrs), and 42 patients with active inflammatory disease (M/F: 13/29, mean age: 39.3 +/- 14.9 yrs) were enrolled in this study. Flow cytometry was used to assess the prevalence of CD64-bearing PMN in whole blood samples. RESULTS: The prevalence of CD64-bearing PMN was significantly higher in patients with infectious disease (77.1 +/- 18.4), inflammatory disease (37.1 +/- 27.5), and active BD (48.9 +/- 22.5) than in healthy controls (9.5 +/- 7.8) or patients with inactive BD (12.9 +/- 9.5). CD64 expression was similar in controls and patients with inactive BD. In the infectious disease group, expression of CD64 was significantly higher than in the active BD and active inflammatory disease groups, while there was no significant difference between the groups of patients with active BD and inflammatory disorders. CONCLUSION: Neutrophil CD64 expression increases during exacerbation of BD. This increase appears to be a non-specific inflammatory response and does not reflect PMN activation triggered by a living microorganism.

Adult↗

PubMed2004

Is vitamin D hypothesis for schizophrenia valid? Independent segregation of psychosis in a family with vitamin-D-dependent rickets type IIA.

The vitamin D hypothesis of schizophrenia is a recent concept bringing together old observations on environmental risk factors and new findings on the neurodevelopmental effects of vitamin D. Candidate genes related to the vitamin D endocrine system have not yet been fully explored for this purpose. The coexistence of vitamin-D-dependent-rickets type II with alopecia (VDDR IIA) and different forms of psychosis in the same inbred family has provided us with an opportunity to investigate the presumed relationship between vitamin D deficiency and psychosis. Psychiatric examination and molecular genetic studies were performed in this family overloaded with psychotic disorders and VDDR IIA. Forty members were evaluated in order to describe their phenotypic features. The family was tested for a linkage to the chromosome 12q12-q14 region where the vitamin D receptor (VDR) gene is located. Psychosis was the common phenotype in the 18 psychiatrically affected members. Pedigree analysis did not show a cosegregation of psychosis and rickets. Lod scores were not significant to prove a linkage between psychosis and VDR locus. The authors concluded that (1) the neurodevelopmental consequences of vitamin D deficiency do not play a causative role in psychotic disorders, (2) these two syndromes are inherited independently, and (3) vitamin D deficiency does not act as a risk factor in subjects susceptible to psychosis.

Adolescent↗

PubMed2004

Levamisole: might it be used in treatment and prevention of atopic diseases?

As an antihelmintic and Th1-biased immunostimulant, levamisole has been used to restore impaired cell mediated immunity. We sought to explore whether the Th1 driving effect of levamisole may also have an influence on the course of allergic diseases, by shifting the Th2 dominant immunity more toward Th1-mediated response. BALB/c mice were sensitized intraperitoneally on days 0, 7, and 15 with ovalbumin (OVA). After the sensitization, they were challenged intranasally with OVA once a day for 6 consecutive days. Levamisole (2.5 mg/kg) was administered orally three times a week during sensitization and challenge. After the last challenge, differential cell counts were performed, and IL-4 and IFNgamma levels were measured in the bronchoalveolar lavage fluids (BALF). Serum total IgE level was determined, and lungs were examined histologically. The present study establishes that mice administered with oral levamisole gave significantly lower IL-4 levels on sensitization with OVA; however, IFNgamma production, eosinophil infiltration, and serum IgE levels remained unaffected. In conclusion, use of levamisole may have important implications in the management of the allergic inflammation.

Adjuvants, Immunologic↗

PubMed2003

The potential effect of short-course high-dose steroid on the maturation and apoptosis of leukemic cells in a child with acute megakaryoblastic leukemia.

High-dose methylprednisolone (HDMP) treatment has been shown to induce differentiation of myeloid leukemic cells in children with acute promyelocytic leukemia and other subtypes (FAB AML M1-M2-M4) of acute myeloblastic leukemia. In the present study, a child with acute megakaryoblastic leukemia (AMKL) was given HDMP (30 mg/kg/day) orally in a single dose for the first 4 days of induction therapy. A marked decrease in peripheral blood blast cells and an increase in platelet count associated with a striking change in bone marrow (BM) morphology was observed following a short-course of HDMP treatment alone. BM cells developed distinct morphology characterized by cytoplasmic blebbing and some appeared as platelet producing micromegakaryocytes. Flow cytometric analysis of the BM cells 4 days after HDMP treatment demonstrated a decrease in the percentage of cells co-expressing CD34 and CD117 antigens and a marked increase in CD42a antigen. These changes in BM morphology and immunophenotype may suggest maturation effect of HDMP on megakaryocytic leukemic cells. In addition ultrastructural analysis of BM cells cultured with methylprednisolone (10(-3) and 10(-6) M) for 24 and 48 h showed numerous apoptotic cells. This was coincident with a significant increase in the percentage of annexin positive cells. These results suggest that HDMP treatment may induce differentiation and apoptosis of leukemic cells in a child with AMKL and it could be a promising agent for remission induction of patients with AMKL.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2003

[Hunting the susceptibility gene for psychosis: a study of a family overloaded with schizophrenia and bipolar disorder].

OBJECTIVE: It is a long-standing debate whether schizophrenia and bipolar disorder are separate clinical entities or different poles on a spectrum. In this paper we present a family overloaded with schizophrenia, and schizoaffective, bipolar and unipolar disorders. Common loci for bipolar affective disorder and schizophrenia were tested by linkage analysis. METHOD: The pedigree of an index family which had been followed by our department for nearly 20 years was extended. The index family members were diagnosed by two psychiatrists with two distinct structured interview schedules (SCID-I and SADS-L). A field visit was undertaken for the evaluation of the extended family (n= 40) and SADS-L was used for psychiatric assessment. Blood samples were collected for molecular studies. A linkage study has been performed for overlapping susceptibility regions for schizophrenia and affective disorders (10p13-p12, 13q32, 18p and 22q11-q13) and a locus (20p11.2-q13) to which a linkage had been shown in a bipolar family who lived in the same region. Both autosomal recessive and dominant mode of inheritance were assumed in the analysis. RESULTS: The pedigree consisted of 108 individuals of whom 23 are affected. All affected subjects presented psychotic features except for 5 unipolar patients. The pedigree was reconstructed with respect to psychosis phenotype. Further linkage and haplotype analysis excluded all five loci on chromosomes 10, 13, 18, 20 and 22 under both autosomal dominant and recessive modes of inheritance assumption. CONCLUSION: A potential linkage between the psychosis gene and reported susceptibility loci overlapping in bipolar affective disorder and schizophrenia was not demonstrated Genome-wide analysis should be performed.

Adult↗