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Öğe Brain metabolite changes on proton magnetic resonance spectroscopy in children with poorly controlled type 1 diabetes mellitus(Springer, 2005) Sarac, K; Akinci, A; Alkan, A; Aslan, M; Baysal, T; Özcan, CThe metabolite changes in the brains of children with poorly controlled type 1 diabetes mellitus (DM) were investigated by proton magnetic resonance spectroscopy (MRS). A total of 30 subjects and 14 age-matched healthy volunteers underwent single-voxel MRS (TE: 136). The duration of disease, medication, presence of hypoglycaemia episodes and the level of haemoglobin A1C (HbA1C) in the patients were noted. Voxels were placed in the pons, left basal ganglion (LBG) and left posterior parietal white matter (PPWM). N-acetylaspartate (NAA)/creatinine (Cr) and choline (Cho)/Cr ratios were calculated. The average HbA1c level was 11.9 +/- 3.4 (8.2-19.4). The average number of keto-acidosis episodes was 1.9 +/- 2.2 (0-9) and the average number of daily insulin injections was 2.8 +/- 0.97 (2-4). MRS revealed lower NAA/Cr and Cho/Cr ratios in the pons and lower NAA/Cr ratio in the PPWM of patients with DM than in control subjects. No significant correlation was observed between the number of hypoglycaemia episodes and metabolite ratios. Metabolic abnormalities have been observed by MRS in the brain of poorly controlled type 1 DM children. These metabolic changes, in particular in the pons region, include a decrease in NAA, indicating neuronal loss or functional impairment, and likely explanations for a decrease in Cho may be dynamic changes in membrane lipids and/or decreased membrane turnover.Öğe Brain MR spectroscopy in children with a history of rheumatic fever with a special emphasis on neuropsychiatric complications(Elsevier Sci Ireland Ltd, 2004) Alkan, A; Kutlu, R; Kocak, G; Sigirci, A; Emul, M; Dogan, S; Aslan, MPurpose: To investigate whether there are metabolite changes in basal ganglia of children with complete healing of rheumatic fever (RF), history of Syndenham chorea (SC) and obsessive compulsive-tic disorder (OCTD) developed after RF when compared with healthy controls and each other. Material and methods: A total of 49 children with history of RF and 31 healthy controls were included into the study. All patients and control group underwent a detailed neuropsychiatric evaluation. Children with the history of RF were classified into-three groups as; group 1: with history of RF without neuropsychiatric complications (NCRF), group 2: only with history of SC (HSC), group 3: with HSC and OCTD (OCTD). After MR imaging, single voxel MR spectroscopy was performed in all subjects. Voxels (15 x 15 x 15 mm) were placed in basal ganglia. N-acetyl aspartate (NAA)/creatin (Cr), and choline (Cho)/Cr ratios were calculated. Results: OCTD were detected in 13 children with HSC. NAA/Cr ratio was found to be decreased in these children when compared with NCRF (n:29), HSC without OCTD (n:7) and control groups (n:3 1). No significant difference was found in metabolite ratios of children with HSC without OCTD when compared with NCRF and control groups. There were no significant differences in Cho/Cr ratio between patient and control groups. Conclusion: Although MR imaging findings was normal, MR spectroscopy findings (decreased NAA/Cr ratio) in our study support the neuronal loss in basal ganglia of children with OCTD and could indicate the development of permanent damage. (C) 2003 Elsevier Ireland Ltd. All rights reserved.Öğe Degradation of vincristine by myeloperoxidase and hypochlorous acid in children with acute lymphoblastic leukemia(Pergamon-Elsevier Science Ltd, 2003) Özgen, O; Türköz, Y; Stout, M; Özugurlu, F; Pelik, F; Bulut, Y; Aslan, MVincristine (VCR) is an effective drug against acute lymphoblastic leukemia (ALL), many solid tumors, but not acute myeloid leukemia. It has been hypothesized that resistance of myeloblasts to VCR is related to myeloperoxidase (MPO) and production of hypochlorous acid (HOCl). We investigated the relationship between VCR degradation and MPO expression and serum HOCl concentrations in pediatric patients with ALL, lymphoma and solid tumors. We studied the sera from 43 children, of which 23 were newly diagnosed and as yet untreated cancer patients, 10 on chemotherapy and 10 healthy control subjects. Patients' sera were incubated with VCR alone or in the presence of taurine (T) or acetaminophen (APAP) and post-incubation VCR and HOCL concentrations were measured. Significant correlations between serum MPO expression, HOCl concentrations and VCR degradation were seen. In the chemotherapy group, MPO-positive patients produced high levels of HOCl and reciprocally low post-incubation VCR levels. HOCl and VCR concentrations in this group were significantly different than other groups studied. Both APAP and T inhibited VCR degradation in the sera of the chemotherapy group but not to the same degree. The effects seen here were consistent for both ALL and the lymphoma/solid tumor cases. Our results indicate that HOCl can increase VCR degradation in vitro in the serum and this effect is significantly more pronounced in pediatric patients undergoing chemotherapy. (C) 2003 Elsevier Science Ltd. All rights reserved.Öğe Delayed myelination in a rhizomelic chondrodysplasia punctata case: MR spectroscopy findings(Elsevier Science Inc, 2003) Alkan, A; Kutlu, R; Yakinci, C; Sigirci, A; Aslan, M; Sarac, KRhizomelic chondrodysplasia punctata is a member of genetic peroxisomal disorders. Delayed myelination, which is probably related to the inadequacy of plasmalogens biosynthesis, is an important feature of this disorder. Direct assessment of neuropathologic aspects of RCDP syndrome such as neuronal degeneration and delayed myelination is possible with MR spectroscopy. In this report, MR spectroscopy findings (decreased Cho/Cr and increased Ins-Gly/Cr ratios and increased levels of mobile lipids) of a rhizomelic chondrodysplasia punctata case supporting delayed myelination are presented. This is the second report of MR spectroscopy examination of the specific brain metabolic changes associated with rhizomelic chondrodysplasia punctata. (C) 2003 Elsevier Science Inc. All rights reserved.Öğe Early- and late-state subacute sclerosing panencephalitis: Chemical shift imaging and single-voxel MR spectroscopy(Amer Soc Neuroradiology, 2003) Alkan, A; Sarac, K; Kutlu, R; Yakinci, C; Sigirci, A; Aslan, M; Baysal, TBACKGROUND AND PURPOSE: Subacute sclerosing panencephalitis (SSPE) is a rare, progressive, inflammatory neurodegenerative disease. Our aim was to determine the metabolic abnormalities of brain in early- and late-stage SSPE by using MR spectroscopy and to assess areas of involvement in the early stages when MR imaging findings were normal. METHODS: Children with stage II (n = 3) or III (n = 3) SSPE and 10 healthy, age-matched children underwent MR imaging, multivoxel MR spectroscopy, and short-echo single-voxel MR spectroscopy (SVS). Areas of involvement in the brain were determined with chemical shift imaging. For SVS, 2 x 2 x 2-cm voxels were placed in the frontal subcortical white matter (FSWM) and parieto-occipital white matter (POWM). N-acetylaspartate (NAA)/creatine (Cr), choline (Cho)/Cr, myo-inositol (Ins)/Cr, and NAA/Cho ratios were calculated. RESULTS: Comparisons of NAA/Cr, Cho/Cr, Ins/Cr and NAA/Cho ratios between patients and control subjects showed significant differences in FSWM and POWM (P <.0l). In patients with SSPE, NAA/Cr ratios in POWM were significantly less than those in FSWM (P <.0l). NAA/Cr ratios in patients with stage II SSPE and those in the control group were not significantly different; this may reflect the absence of neuronal loss. Decreased NAA/Cr, increased Cho/Cr and Ins/Cr ratios, and increased lactate and lipid peaks were found in patients with stage III SSPE. CONCLUSION: MR spectroscopy showed findings suggestive of inflammation in stage II and findings of demyelination, gliosis, cellular necrosis, and anaerobic metabolism in stage III. MR spectroscopy could be a promising technique for early diagnosis and treatment planning in cases of SSPE.Öğe The effect of long-term therapy with sodium valproate on oxidant/antioxidant status in epileptic children(Wiley, 2003) Ozerol, E; Aslan, M; Cakmak, EA; Gulec, M; Yakinci, C; Akyol, OAntiepileptic drugs may cause the changes in the oxidant/antioxidant status of the body. Reactive oxygen species have been suggested to be an important factor in the pathogenesis of various diseases as well as drug interactions and/or adverse effects. The aim of this study, therefore, is to investigate the status of major antioxidant enzyme activities as well as the end products of lipid peroxidation in erythrocyte and plasma from epileptic children after therapy with sodium valproate (VPA). Superoxide dismutase (SOD), catalase (CAT) activities and malondialdehyde (MDA) levels in erythrocyte and plasma were analyzed in 41 epileptic patients under long-term antiepileptic therapy with VPA and 32 healthy controls. Erythrocyte SOD activity was found to be increased (p=0.024) whereas erythrocyte CAT activity decreased (p=0.016) in patients with epilepsy under VPA treatment compared to the controls. MDA levels in erythrocyte were found to be markedly decreased in epileptic children compared to controls (p<0.001). In conclusion, decreased CAT activity seems to be compensated with increased SOD activity in erythrocytes protecting erythrocyte membranes from lipid peroxidation in patients with epilepsy under VPA treatment.Öğe Infantile Sandhoff's disease: Multivoxel magnetic resonance spectroscopy findings(B C Decker Inc, 2003) Alkan, A; Kutlu, R; Yakinci, C; Sigirci, A; Aslan, M; Sarac, KSandhoff's disease is a rare, genetic lysosomal storage disease leading to delayed myelination or demyelination. Although neuroimaging findings in this disease have been reported previously, magnetic resonance spectroscopy findings have not been reported. In this report, we present magnetic resonance imaging and magnetic resonance spectroscopy features of two cases with Sandhoff's disease. Magnetic resonance spectroscopy revealed findings indicating widespread demyelination in both cases and neuroaxonal loss and anaerobic metabolism in the second case. Magnetic resonance spectroscopy could provide useful information in the explanation of the clinical picture of cases with Sandhoff's disease.Öğe Malignant melanoma of the soft parts showing calciphylaxis(Taylor & Francis Inc, 2003) Kutlu, NO; Aydin, NE; Aslan, M; Bulut, T; Özgen, ÜCalciphylaxis 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.Öğe Merosin-negative congenital muscular dystrophy: magnetic resonance spectroscopy findings(Elsevier Science Bv, 2005) Aslan, M; Alkan, A; Yakinci, C; Sonmezgoz, E; Bicak, U; Zorludemir, SCongenital muscular dystrophies (CMD) are heterogenous group of muscle disorders with autosomal recessive inheritance. Merosin deficiency has been identified in some patients with CMD all of whom also had white matter abnormalities on MRI. In postmortem studies, the brain showed extensive myelin pallor with a spongy appearance of white matter and moderate astrocytosis or demyelination. Direct assessment of neuropathologic aspects of MN-CMD such as demyelination is possible with MR spectroscopy (MRS). Although previous reports have described several neuro-imaging findings of this disease, MRS findings have not been reported in literature. In this case, we report MRS features of a 4-year old girl with MN-CMD. MRS of brain demonstrated that N-acetylaspartate (NAA)/Creatine (Cr) ratio was normal. Increased Choline (Cho)/Cr and Myo-inositol (MI)/Cr ratios were obtained. These findings were interpreted as demyelination and gliosis of white matter. (c) 2004 Elsevier B.V. All rights reserved.Öğe Neurofibromatosis type 1: Diffusion weighted imaging findings of brain(Elsevier Ireland Ltd, 2005) Alkan, A; Sigirci, A; Kutlu, R; Ozcan, H; Erdem, G; Aslan, M; Ates, OPurpose: The purposes of this study were to evaluate the differences in apparent diffusion coefficient (ADC) values between infra and supratentorial unidentified bright objects (UBOs), between UBOs and normal appearing side (NAS, contralateral regions of the UBOs and/or normal appearing region without UBOs) in the neurofibromatosis type 1 patients (NF1) and control group and also to investigate correlation between age and ADC values. Methods: A total of 30 patients and 26 healthy controls were included. The MRI examination consisted of routine imaging and diffusion weighted imaging (DWI). Seven distinct locations (frontal, parieto-occipital and cerebellar white matter, globus pallidum, thalamus, hippocampus, and midbrain) were selected for the analysis. The ADC values were calculated directly from these automatically generated ADC maps with ROI. Results: The ADC values of UBOs were significantly increased in cerebellar white matter, hippocampus, globus pallidum, midbrain, and thalamus when compared with NAS and control group. There were statistically significant differences between NAS and control group in the ADC values obtained from hippocampus and thalamus. There were statistically significant differences between supra and infratentorial UBOs in ADC values. There was a negative correlation between age and the ADC values obtained from normal appearing midbrain, hippocampus, thalamus, and globus pallidum. Conclusion: ADC values both in UBOs and in the normal appearing locations as hippocampus and thalamus were detected to be higher in the patients with NF1. The detection of lesions might be independent of MRI appearance in NF1, i.e. although the brain is affected, MRI appearance may be normal. Therefore, DWI and ADC values should also be utilized in the delineation of brain involvement of NF1 patients. (C) 2005 Elsevier Ireland Ltd. All rights reserved.Öğe Proton MR spectroscopy features of normal appearing white matter in neurofibromatosis type 1(Elsevier Science Inc, 2003) Alkan, A; Sarac, K; Kutlu, R; Yakinci, C; Sigirci, A; Aslan, M; Ozcan, HTo determine whether differences exist between neurofibromatosis type 1 (NF1) patients with or without focal lesions and healthy normal volunteers in the metabolite ratios of normal appearing white matter, 27 patients with NF1 (with parenchymal lesion, MR positive, n: 17; without parenchymal lesions, MR negative, n: 10) and 20 healthy volunteers underwent MRI and short TE (31 ms) proton MR spectroscopy (MRS). In 17 patients with parenchymal lesions, 61 focal lesions were detected by MRI. MRS was performed from normal appearing frontal and posterior parietal white matter (FWM and PWM) in NF1 and from control groups. NAA/Cr, Cho/Cr and MI/Cr ratios were calculated. Significant increase in Cho/Cr and MI/Cr ratios were found in FWM and PWM in MR negative and positive groups when compared to control group. NAA/Cr ratio in MR positive group was significantly decreased in FWM compared to control group. There were no significant differences between FWM and PWM in all metabolite ratios of MR negative group. MI/Cr ratio in MR positive group was significantly elevated in PWM compared to FWM. Metabolite changes detected by MRS could indicate demyelination and gliosis in normal appearing white matter in all NF1 patients, and additionally neuroaxonal damage in the FWM of NF1 patients with focal lesions. For that reason, in the clinical evaluation and follow-up of these patients MRS features of normal appearing white matter should be considered in addition to focal lesions. (C) 2003 Elsevier Inc. All rights reserved.Öğe Pyridoxine-dependent seizures: Magnetic resonance spectroscopy findings(B C Decker Inc, 2004) Alkan, A; Kutlu, R; Aslan, M; Sigirci, A; Orkan, I; Yakinci, CPyridoxine-dependent seizures are an extremely rare genetic disorder. Early diagnosis and treatment are important for the prevention of permanent. brain damage. Elevated levels of glutamate and decreased levels of gamma-aminobutyric acid (GABA) in the frontal and parietal cortices are among the characteristic features of this disorder. These metabolic abnormalities eventually lead to seizures and neuronal loss. In this case report, we present magnetic resonance spectroscopy findings of a 9-year-old girl with pyridoxine-dependent seizures with mental retardation. The N-acetylaspartate-to-creatine, ratio was found to be decreased in the frontal and parieto-occipital cortices, which could indicate neuronal loss. Magnetic resonance Spectroscopy could be a useful tool in the neuroiniaging evaluation for assessment of parenchymal changes despite a normal-appearing brain magnetic resonance image in patients with pyridoxine-dependent seizures.Öğe A rare complication of generalized edema in juvenile dermatomyositis: a report of one case(Elsevier Science Bv, 2004) Karabiber, H; Aslan, M; Alkan, A; Yakinci, CJuvenile dermatomyositis (JDM) is a rare autoimmune disease characterized by inflammation of the muscle, connective tissue, skin, gastrointestinal tract and small nerves. Periorbital and facial edema may also be associated. Although localized edema is a common feature of juvenile dermatomyositis, generalized edema has been reported rarely. In this article, we report a 14-year-old boy with juvenile dermatomyositis presenting with generalized edema. Of the diagnostic criteria of JDM, severe symmetric weakness of the proximal musculature, characteristic cutaneous changes, elevated serum muscle enzymes and myopathic electromyographic abnormalities were observed. Magnetic resonance imaging (MRI) of the lower extremities and pelvis showed marked diffuse edema in the subcutaneous tissue, muscles and myofascia. We suggest that MRI findings, which are not among the diagnostic criteria, may also be included in the diagnostic criteria of JDM. To the best of our knowledge, this is the 19th case of JDM reported for generalized edema in the English literature. (C) 2003 Elsevier B.V. All rights reserved.Öğe Renal interlobar artery parameters with duplex Doppler sonography and correlations with age, plasma renin, and aldosterone levels in healthy children(Amer Roentgen Ray Soc, 2006) Sigirci, A; Hallaç, T; Akyncy, A; Temel, S; Gülcan, H; Aslan, M; Koçer, MOBJECTIVE. The objectives of this study were to compare and make correlations between age and Doppler parameters of the interlobar arteries, including synchronously obtained plasma renin and aldosterone levels and to obtain new normative data regarding acceleration time in healthy children from neonates to 16 years. SUBJECTS AND METHODS. One hundred sixty-nine healthy children (72 girls and 97 boys) were classified into four groups: group 1 (< 1 year; n = 34), group 2 (range, 1-6 years; n = 48), group 3 (range, 6-12 years; n = 50), and group 4 (range, 12-16 years; n = 37). Blood samples from the renin and aldosterone were collected in the morning after bed rest and fasting. The resistive index (RI), pulsatility index (PI), and the acceleration time of the renal interlobar arteries with duplex Doppler sonography, including both kidney longitudinal lengths with gray-scale sonography, were evaluated. One-way analysis of variance with the least significant difference post-hoc test and Pearson's correlation test were used to compare the differences between groups and to make correlations, respectively. An independent-sample t test was used to evaluate the differences between all parameters based on sex and to compare the left and right kidney longitudinal lengths in each group. RESULTS. The RI, PI, and acceleration time were statistically significant in between-group comparisons. Only in group 4 was acceleration time not statistically significant compared with groups 2 and 3. Plasma renin levels were significantly higher in group 1 compared with groups 2 (p < 0.03) and 4 (p < 0.0001); in group 2 compared with group 4 (p < 0.05); and in group 3 compared with group 4 (p < 0.01). The plasma aldosterone levels were significantly higher only in group 1 compared with groups 2 (p < 0.001), 3 (p < 0.008), and 4 (p < 0.0001). The RI correlated linearly with the PI, plasma renin levels, and aldosterone levels and correlated inversely with acceleration time. Age had a negative correlation with the RI, PI, plasma renin levels, and aldosterone levels and correlated positively with acceleration time. There were no statistically significant differences between all parameters based on sex and no significant difference found between the right and left kidney longitudinal lengths in each group. CONCLUSION. The RI in children up to 54 months old is higher than in adults. Therefore, the adult mean renal RI criterion of 0.70 should be applicable to children 54 months old and older. We showed that the age dependency of the RI was directly related to that of plasma renin and aldosterone levels in healthy children in whom Doppler parameters and blood analysis were evaluated synchronously.Öğe Subacute sclerosing panencephalitis with fulminating course: Follow-up magnetic resonance spectroscopy (MRS) findings(Sage Publications Inc, 2004) Alkan, A; Kutlu, R; Sigirci, A; Aslan, M; Sarac, K; Yakinci, CThe fulminating form of subacute sclerosing panencephalitis is an extremely rare condition. Imaging findings are usually not correlated with clinical staging. We describe a 4-year-old girl with severe neuronal loss, demyelination, and gliosis in subcortical white matter by magnetic resonance spectroscopic examination even though she was diagnosed as clinical stage II. In 2 months' time, her clinical status worsened significantly. Follow-up magnetic resonance spectroscopy revealed findings that were consistent with clinical status. It is our opinion that magnetic resonance spectroscopy could demonstrate a rapidly progressive fulminating course of subacute sclerosing panencephalitis even in the early clinical stages.Öğe Sympathetic skin responses in type-1 diabetic children: Relationship to urodynamic findings(Wiley, 2006) Soylu, A; Akinci, A; Yilmaz, U; Sarier, M; Aslan, M; Oman, CAims: Cystopathy is an important problem in diabetes mellitus (DM) when diabetes is not well-controlled. In most cases of diabetic csytopathy, autonomic involvement is responsible, which develops insidiously over a long time. We investigated the hand and genital sympathetic skin responses (SSRs) and its relation to urodynamic abnormalities in this group of patients. Methods: We performed hand and genital SSRs in 24 children with Type-1 DM,whose hemoglobin A1C values were above normal limits. We also recruited 19 healthy children for SSRs measurements. Cystometry was performed in 24 children with Type-1 DM. Based on cystometry findings, these children were classified into two groups as normal (n:6) and abnormal (n:18). The amplitude and latency of hand and genital SSRs of 24 children with Type-1 DM and 19 healthy children were compared. Results: Hand and genital SSRs were obtained from all of the diabetic and healthy children. The mean genital SSRs amplitude in diabetic children was significantly lower than the controls. There was no difference in the mean values of all investigated parameters between the normal group and controls. When compared to the controls, there was prolonged latency and decreased amplitude of genital SSRs and decreased hand SSRs amplitude in abnormal group. Conclusions: SSR is a non-invasive test for the evaluation of autonomic sympathetic involvement. Our study revealed differences in genital SSR before the manifestations of cystopathy. Children with abnormal urodynamic findings had changes in both hand and genital SSRs. These findings suggest that SSR tests may have a place in the evaluation of diabetic cystopathy in the early asymptomatic period.
