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A Kara

Publications and source records attributed to A Kara.

At least 19 recordsLinked to original sources
PubMed2006

Morphometric comparison of the human corpus callosum in deaf and hearing subjects: an MRI study.

Auditory cortices are interconnected to each other by fibers passing through the corpus callosum (CC). In totally deaf persons no auditory impulses are conveyed to the auditory cortices, hence the auditory pathways become nonfunctional. It was reported that there has been cross-modal plasticity between auditory, visual, and somatosensory cortices. In this study, our aim was to make a comparison in the CC morphometry in hearing subjects and in a selected group in which the auditory system was deprived before the age of 2. 18 deaf and 18 hearing male, handedness matched volunteers, ages varying between 28 and 56 years old were examined. Audiometrical tests were applied to both groups and then T1-weighted midsagittal MR images were obtained. Certain dimensions and areas were measured on these images. There were no statistically significant difference between deaf and hearing subjects, either when dimensions and areas were analyzed by multivariate analysis of variance or when areas were analyzed by univariate analysis of variance. Absence of any significant morphometric difference in the CC of deaf subjects could be thought as an evidence of reflection of functional cortical plasticity.

Adult↗
PubMed2006

Long-term beneficial effects of dexamethasone on intellectual and neuropsychological outcome of children with pneumococcal meningitis.

A Substantial ratio of bacterial meningitis survivors suffers mild or serious intellectual and neuropsychological handicaps. We organized eighty subjects into three groups: 1) Pneumococcal meningitis (PM) who did not receive dexamethasone, 2) PM who received dexamethasone, 3) Other bacterial meningitis with different etiology. All subjects underwent Bender Visual Motor Gestalt test and age-appropriate Intelligence quotient (IQ) tests. The mean full-scale IQ scoring fell within normal range (90+/-17) in the post-meningitic cohort. There was no statistical difference between two pneumococcal groups regarding full scale IQ testing (88+/-16 and 91+/-18) and Bender-Gestalt scoring (4.0+/-3.3 and 3.8+/-2.6), respectively. However, the subjects with full scale IQ score <85 (below the average) were statistically less in the group with steroid therapy. PM patients who received dexamethasone therapy had statistically better academic performance. As a result, adjuvant steroid therapy has no significant impact on overall intellectual tests in PM subjects. However, dexamethasone seems to diminish development of below the average IQ scoring in PM cases. In addition, PM subjects who received steroids showed better academic achievement. These findings may support the idea of dexamethasone administration prior to first antibiotic dose in PM subjects.

Adolescent↗
PubMed2003

Optical recognition of atomic steps on surfaces.

Visible and UV light spectra display striking differences in optical reflectivity for the two types of monatomic steps on copper (111) surfaces. Electronic structure calculations trace these differences to the specific contributions of p(axially) and p(radially) local densities of states, parallel and perpendicular to the steps, of the distinctly coordinated corner atoms. The local origin of the spectral reflectance anisotropy is further corroborated by experiments on Cu(111) surfaces with varying step densities. Site specificity of the electronic structure of atoms in low coordinated sites on Cu(111) vicinals is thus revealed by reflectance anisotropy spectroscopy which can thereby detect step atom densities down to 10(13) atoms/cm(2).

Journal Article↗
PubMed2003

Osteopetrosis and Glanzmann's thrombasthenia in a child.

Autosomal recessive osteopetrosis is a rare, fatal disease characterized by accumulation of excessive bone mass due to defective bone resorption. The pathogenesis of osteopetrosis is controversial. Osteoblast-osteoclast interaction defects, incorrect differentiation of osteoclasts, abnormal contact between osteoclast and extracellular matrix, and abolished signaling are included in this process. Recently, mutations in the gene of the vacuolar proton pump have been described in some cases of recessive osteopetrosis. Glanzmann's thrombasthenia (GT) is a rare hereditary qualitative platelet disorder characterized by a lifelong bleeding tendency due to quantitative and qualitative abnormalities of the platelet integrin alpha(IIb) beta3. Several mutations on either integrin alpha(IIb) [glycoprotein (GP) IIb] or integrin beta(3) (GP IIIa) were reported in GT. We report on a patient with autosomal recessive osteopetrosis concurrently diagnosed with variant type Glanzmann's thrombasthenia. To our knowledge, our patient was the first case reported in the literature in which osteopetrosis and Glanzmann's thrombasthenia were diagnosed together.

Genes, Recessive↗
PubMed2003

Effects of oral montelukast on airway function in acute asthma.

Montelukast, a specific cysteinyl leukotriene receptor antagonist, has been shown to improve pulmonary function within 1 h of ingestion. This study was undertaken to compare the effects on peak expiratory flow rate (PEFR) of oral montelukast added to intravenous steroid, intravenous steroid alone and placebo during the 24 h period following administration. Seventy asthmatic patients (FEV1 40-80% predicted and > or = 15% improvement after inhaled beta agonist) were enrolled in a single blind study to receive oral montelukast (10 mg) plus intravenous prednisolone (1 mg/kg), intravenous prednisolone (1 mg/kg) or placebo in a randomised fashion. The patients received one ofthe above three groups of medication before any other treatments. This was immediately followed by the aerosol treatments of 100 mcg of terbutaline sulphate divided into three doses during 1 h as described in the consensus statement. Thereafter, patients were observed for 24 h to document the effects on PEFR, Borg dyspnoea score and need for rescue medication. The primary end point was percentage change at different time points. Secondary end points were Borg dyspnoea score and use of rescue medication. Compared with placebo, montelukast added to the prednisolone group and the prednisolone alone group had significant percentage change from baseline in PEFR in the entire 24 h period (P<0.05). The difference in PEFR between montelukast plus prednisolone group and prednisolone group favoured the montelukast plus prednisolone group but did not reach statistical significance. Furthermore, montelukast plus prednisolone group required less inhaled short-acting beta agonistthan other two groups. The results of this study indicate that adding montelukast to steroid in acute asthma may have some additive improvement in lung functions.

Acetates↗
PubMed2002

Spontaneous haemothorax: an uncommon presentation of Glanzmann thrombasthenia.

UNLABELLED: Glanzmann thrombasthenia is a rare hereditary qualitative platelet disorder characterized by a lifelong bleeding tendency due to quantitative and qualitative abnormalities of the platelet integrin alpha(IIb)beta3. Common clinical manifestations include purpuric type skin bleeding, prolonged bleeding from minor cuts, epistaxis, gingival bleeding and menorrhagia. Less frequently, gastrointestinal system bleeding may occur. Haemarthrosis, haematuria, intracranial and visceral haemorrhage are very rare symptoms. This study reports a 3-y-old girl with Glanzmann thrombasthenia who presented with life-threatening haemothorax. There was no history of recent trauma or drug usage and no vascular or parenchymal abnormalities to explain the development of haemothorax. CONCLUSION: To the authors' knowledge this is the first case of Glanzmann thrombasthenia complicated by spontaneous haemothorax.

Child, Preschool↗
PubMed2001

[Anticancer chemotherapy, risk factor for infection at the operated site in cervicofacial surgery].

BACKGROUND: In order to evaluate occurrence and risk factors for wound infection (WI) in head and neck uncontaminated surgery, we carried out a prospective study. METHODS: From january 1997 through january 1999, we prospectively evaluated 212 wounds of all patients having uncontaminated head and neck surgery at the Oscar Lambret Cancer Center (neck dissections, parotidectomies, thyroidectomies, explorative cervicotomies, cutaneous resections). No antibiotic prophylaxis was given. WI was defined as a wound with pus. Statistical evaluation was performed using the chi 2 test. In univariate analysis, differences were considered significant p < 0.05. RESULTS: The overall WI rate was 6.6% (14/212). In univariate analysis, previous chemotherapy is the only risk factor for WI were: (p < 0.00001). Multivariate analysis was not performed. CONCLUSION: Like other cancer locations, chemotherapy was a major risk factor for WI. In these cases, a phase ill trial could confirm efficacy of standard antibiotic.

Adult↗
PubMed2001

Validity of the quasiharmonic analysis for surface thermal expansion of Ag(111).

For temperatures above 0.6T(m) (the bulk melting temperature) we show that the quasiharmonic approximation leads to increasingly larger values of the surface thermal expansion of Ag(111) as compared to that obtained from molecular dynamics simulations based on fully anharmonic interaction potentials. The inadequacy of the quasiharmonic approximation is traced to the excessive softening of the surface phonon frequencies. We discuss the validity of the quasiharmonic approximation for surfaces at elevated temperature, in view of recent x-ray scattering data on Ag(111).

Journal Article↗
PubMed2001

Risk factors for wound infection in head and neck cancer surgery: a prospective study.

BACKGROUND: The goal of this prospective study is to determine risk factors for wound infections (WI) for patients with head and neck cancer who underwent surgical procedure with opening of upper aerodigestive tract mucosa. METHODS: One hundred sixty-five consecutive surgical procedures were studied at Oscar Lambret Cancer Center within a 24-month interval. Twenty-five variables were recorded for each patient. Statistical evaluation used Chi2 test analysis (categorical data) and Mann-Whitney test (continuous variables). RESULTS: The overall rate of WI was 41.8%. Univariate analysis indicated that five variables were significantly related to the likelihood of WI: tumor stage (p =.044), previous chemotherapy (p =.008), duration of preoperative hospital stay (p = 022), permanent tracheostomy (p =.00008), and hypopharyngeal and laryngeal cancers (p =.008). CONCLUSIONS: Despite antibiotic prophylaxis, WI occurrence is high. These data inform the head and neck surgeon, when a patient is at risk for WI and may help to design future prospective studies.

Adult↗
PubMed2001

Factors associated with utilization of nonproven cancer therapies in Turkey. A study of 135 patients from a single center.

In their search for a cure, a significant number of cancer patients use nonproven treatment (NPT) methods. However, little is known about patient and disease characteristics associated with the use of these methods. In this trial, we evaluated the prevalence of and the factors associated with the usage of nonproven cancer remedies in a teaching hospital in Turkey. A self-administered questionnaire was given to 135 cancer patients attending the outpatient clinics of a medical oncology department. Patients' demographic data, their usage of nonproven methods, and possible contributing factors were explored. Our cohort mainly comprised poor patients with only primary school education. Overall, 50% of our patients had used or were using NPT methods. Medicinal herbs (mainly stinging nettle) were the most frequently used remedy. In contrast, such "complementary therapies" as exercise, relaxation, and meditation were not employed. In multivariate analysis, only duration of disease was found to be significantly associated with NPT utilization [P=0.05, relative risk (RR)=1.94]. In addition, patient education level was marginally significant (P=0.07, RR=0.36). Apart from long duration of disease and being better educated, no other clinical, social, economic and cultural factors evaluated were associated with the use of NPT in our group of Turkish patients. Since these treatments are sometimes costly and have questionable efficacy and toxicity, proper scientific trials are needed to clarify whether such methods have a real role in cancer management.

Adult↗
PubMed2000

Parvovirus B19 infection reminiscent of myelodysplastic syndrome in three children with chronic hemolytic anemia.

The authors have seen transient pancytopenia with erythroid hypoplasia and striking trilineage myelodysplasia reminiscent of true myelodysplastic syndrome (MDS) in 3 children, 1 with thalassemia intermedia and the other 2 with previously undiagnosed hereditary spherocytosis. In these 3 children transient pancytopenia and myelodysplasia coincided with serological evidence of acute parvovirus-B19 (PV-B19) infection, strongly suggesting their relevance. It is of interest that these 3 cases were encountered within a period of 6 months. This might be an incidental event, but it might also be concluded that acute PV-B19 infection associated transient pancytopenia with morphological appearance of MDS may occur more frequently than reported in the literature. So, PV-B19-associated nonclonal MDS should be considered in the differential diagnosis of true clonal MDS.

Child↗
PubMed2000

The protective effect of taurine against gentamicin-induced acute tubular necrosis in rats.

BACKGROUND: Taurine, which is the major intracellular free beta-amino acid, is known to be an endogenous antioxidant and a membrane-stabilizing agent. In this study, we wished to know whether taurine altered the concentration of gentamicin in kidney tissue and could protect against gentamicin-induced acute proximal tubular injury. METHODS: Wistar albino rats of both sexes were assigned to three groups, which all received one of the following daily intraperitoneal injections for 8 days: (i) 0.9% sodium chloride (NaCl) alone at the same volume as gentamicin treated rats (group C; n=8); (ii) 100 mg/kg/day gentamicin alone (group G; n=8, four male, four female); or (iii) 100 mg/kg/day gentamicin plus 7.5 ml/kg/day taurine (group G+T; n=9, five male, four female). Urine was collected for 24 h for the determination of urine volume and creatinine. Intracardiac blood was collected for blood urea nitrogen (BUN) and serum creatinine determination. The kidneys were removed, weighed, and the left kidneys were subjected to biochemical analysis for the determination of thiobarbituric acid-reactive substance (TBARS) and lactate levels, and glutathione peroxidase (Gpx) and superoxide dismutase (SOD) activities. The right kidneys were divided vertically in half. The upper halves were used for histopathological examination, by light and electron microscopy. The lower halves were used to detect the gentamicin concentration within the kidney tissue, by high-performance liquid chromatography (HPLC). Changes in body weight and normalized kidney weight were recorded. RESULTS: Taurine treatment reduced gentamicin-induced increases in serum creatinine, 24 h urine volume, BUN and tissue lactate and TBARS levels (0.57+/-0.02 vs 1.06+/-0.08 mg/dl, P<0.001; 9.00+/-1.46 vs 20.9+/-2.73 ml, P<0.001; 25.3+/-1.87 vs 54.1+/-6.99 mg/dl, P<0. 001; 2.56+/-0.10 vs 3.44+/-0.08 micromol/g wet tissue, P<0.001; and 66.4+/-3.41 vs 79.5+/-5.07 nmol/g wet tissue, P>0.05, respectively). Taurine reduced the accumulation of gentamicin within the kidney tissue (233+/-29 vs 494+/-93 microg/g wet tissue, P<0.05). Taurine treatment also prevented body weight loss due to gentamicin administration (17.8+/-1.64 vs -10.0+/-7.08 g, P<0.01) and normalized reduced Gpx and SOD activities (3.46+/-0.16 vs 2.37+/-0. 15 U/g wet tissue, P<0.01; and 15577+/-377 vs 12662+/-577 U/g wet tissue, P<0.01, respectively). Light microscopic examination of the renal tissues from gentamicin-treated rats revealed severe histopathological changes, whereas specimens obtained from taurine-treated rats revealed only mild changes. This finding was supported by electron microscopic examination. CONCLUSIONS: Our observations suggest that taurine treatment attenuates the accumulation of gentamicin within kidney tissue and counteracts the deleterious effect of gentamicin on renal tubular function. They may have potentially important clinical implications.

Acute Disease↗
PubMed2000

Molecular analysis of turkish beta-thalassemia heterozygotes with normal Hb A2 levels.

Four parents of three unrelated families who are obligatory beta-thalassemia heterozygotes and two parents with Hb Knossos are presented. In these subjects, although the red blood cell counts and red cell indices were compatible with beta-thalassemia trait, the Hb A2 values were between 1.9-2.9% of the total hemoglobin. Examination of the delta-globin gene by Southern blot, restriction endonuclease analysis, and by direct sequencing of amplified DNA revealed the presence of the (delta0) -7.2 kb Corfu type deletion, the (delta+) codon 27 (G-->T) and (delta0) IVS-I-2 (T-->C) mutations in trans or in cis with a severe beta-thalassemia allele, and the (delta0) codon 59 (-A) deletion in cis with the betaKnossos allele.

Adult↗
PubMed1999

Up-regulation of cytokines in glomerulonephritis associated with murine malaria infection.

Malaria infections often cause glomerulonephritis (GN), and multiple factors have been implicated in the pathogenesis of glomerular injury. The role of cytokines in malaria associated glomerulonephritis has not been clearly defined. To study the importance of cytokines in malarial nephritis, we investigated the expression of tumour necrosis factor-alpha (TNF-alpha), interleukin-1alpha (IL-1alpha), IL-6, IL-10 and granulocyte macrophage-colony stimulating factor (GM-CSF) in kidneys acutely infected with murine malaria parasite Plasmodium berghei ANKA in C57BL/6 J mice. Groups of six mice sacrificed on days 5, 8-10, 15, and 20 postinfection, and normal controls were used for cytokine analysis. Elevated levels of messenger RNA (mRNA) specific for these cytokines in infected kidneys after day 5 postinfection were demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis. Kidney sections stained with specific antibodies against TNF-alpha, IL-1alpha, IL-6, IL-10 and GM-CSF by immunohistochemistry showed that the staining for these cytokines on the glomeruli was positive from day 10 postinfection, and increased progressively, mainly in the infiltrating macrophages and the glomerular mesangium. Strong correlation was found between the expression of TNF-alpha with IL-6, and IL-1alpha with IL-6. The expression of TNF-alpha, IL-1alpha, IL-6, and IL-10 also strongly correlated with the severity of proteinuria. Our findings show that there is up-regulation of cytokines in the pathogenesis of glomerulonephritis associated with murine malaria infection.

Animals↗
PubMed1998

A rare complication of renal biopsy in a child with membranoproliferative glomerulonephritis.

Percutaneous renal biopsy is essential for the definitive diagnosis of chronic glomerulonephritis. Large arteriovenous fistula (AVF) which is a rare complication of native renal biopsy is generally diagnosed in the first weeks after the procedure. We present a childhood membranoproliferative glomerulonephritis case with an enormous AVF presenting with severe hypertension 15 months after the biopsy that was successfully embolized. In conclusion, AVF must be considered in children having chronic glomerulonephritides even if hypertension appears late after the renal biopsy.

Aneurysm, False↗
PubMed1998

A comparison of the effect of high-dose methylprednisolone with conventional-dose prednisolone in acute lymphoblastic leukemia patients with randomization.

In this preliminary study the efficacy of high-dose methylprednisolone (HDMP) during remission-induction chemotherapy was evaluated on 166 children with acute lymphoblastic leukemia (ALL). The St. Jude Total Therapy Study XI protocol with minor modifications was used in this trial. Patients were randomized into two groups. Group A received conventional-dose (2 mg/kg/day orally) prednisolone, and group B received high-dose methylprednisolone (HDMP, Prednol-L, 900-600 mg/m2 orally) during remission-induction chemotherapy. Complete remission was achieved in 97% of the children. For the 80 patients who were followed up for 3 years, median follow-up was 44 (range 5-60) months and the 3-year event-free survival (EFS) rate was 68.5%) overall, 58.6% in group A and 78.4% in group B. The EFS among patients in group B was significantly higher than in group A (p=0.05). When we compared the 3-year EFS of groups A and B in the high-risk groups and high-risk subgroups with white blood cell (WBC) counts > or = 50 x 10(9)/l and age > or = 10 years, the survival rates were 45% versus 77.2%, 33% versus 78% and 45% versus 89%, respectively. During the follow-up of 162 patients, relapses were significantly higher in group A. Bone marrow relapses in 162 patients, and also in a subgroup of patients > or = 10 years of age were significantly higher in group A. These results suggest that HDMP during remission-induction chemotherapy improves long-term EFS, particularly for high-risk patients.

Adolescent↗