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N Akalin

Publications and source records attributed to N Akalin.

10 recordsLinked to original sources
PubMed2004

Neurotrophin receptor immunoreactivity in the hippocampus of patients with mesial temporal lobe epilepsy.

Recent evidence supports a critical role of neurotrophins in the regulation of both neuronal survival and synaptic transmission during epileptogenesis. We have examined the immunohistochemical expression of high- (tyrosine kinase receptors, trk) and low-affinity (p75) neurotrophin receptors (NTRs) in the hippocampal specimens from 18 patients with chronic temporal lobe epilepsy [TLE; 14 patients with hippocampal sclerosis (HS) and four with focal lesions (tumours) not involving the hippocampus proper]. Nonepileptic autopsy brains (n = 6) and surgical specimens from tumour patients without epilepsy (n = 3) were used as controls. Immunoreactivity (IR) for the trk receptors (trkA, trkB, trkC) was detected in normal human brain within the pyramidal neurones of hippocampal cornus ammoni (CA) regions and in the dentate gyrus. There were no detectable differences in the neuronal trk IR patterns in the hippocampus between control and TLE cases with HS, except for a decrease in neuronal density in regions where cell death had occurred (CA1, CA3 and CA4). In contrast, a consistent increase in trkA IR was observed in reactive astrocytes in CA1 and dentate gyrus. The low-affinity p75 neurotrophin receptor (p75(NTR)) was expressed in low levels in postnatal normal hippocampus. In contrast, neuronal p75(NTR) IR was detected in 10/14 cases of HS in spared neurones within the CA and hilar regions of the hippocampus. Double labelling revealed that p75(NTR)-positive neurones also contain trk receptor IR. In six cases with prominent glial activation strong p75(NTR) IR was observed in microglial cells within the sclerotic hippocampus. The present results indicate that changes in NTR expression are still detectable in the hippocampus of patients with chronic TLE and involve both glial and neuronal cells. Reactive astrocytes were immunoreactive for trkA, whereas activated microglia cells were reactive for p75(NTR), suggesting different functions for specific NTRs in the development of reactive gliosis. Moreover, the increased expression of p75(NTR) in hippocampal neurones of TLE patients may critically influence the neuronal survival during the epileptogenic process.

Adolescent↗
PubMed2004

The effects of desferrioxamine on cisplatin-induced lipid peroxidation and the activities of antioxidant enzymes in rat kidneys.

Cisplatin-induced nephrotoxicity is associated with an increase in lipid peroxidation and oxygen free radicals in rat kidneys. In this study, the effects of desferrioxamine were compared to vitamin C and E on cisplatin-induced lipid peroxidation and antioxidant enzyme activities in rat kidneys. Rats were divided into five groups, with 15 Wistar rats in each group. In the control group, rats received 1 mL/100 g isotonic saline solution intraperitoneally (i.p.). In Group II, 10 mg/kg cisplatin i.p. was injected to rats. Thirty minutes before the same dosage of cisplatin administration, 100 mg/kg i.p. vitamin C or E was given to rats in groups III and IV, respectively. Rats in Group V received 250 mg/kg desferrioxamine i.p., before the same dose of cisplatin administration. All rats were killed by cervical dislocation after 72 hours. The kidneys were immediately removed and washed in cold saline. Spectrophotometric method was used for all analyses. While catalase, glutathione reductase (GR), and superoxide dismutase (SOD) levels were found to be significantly decreased (P < 0.001), malondialdehyde (MDA) (P < 0.05) and hydrogen peroxide (H2O2) (P < 0.001) levels were significantly increased in the cisplatin group when compared to the controls. MDA levels were decreased by desferrioxamine (P < 0.005) as well as vitamin C and E (P < 0.05 and P < 0.001, respectively). These three compounds induced a significant increase in SOD levels (P < 0.05), but only in the vitamin C group, were SOD levels not significantly different than the levels of the controls (P > 0.05). In the desferrioxamine (P < 0.05), vitamin C and E groups (P < 0.001 for both), the cisplatin elevated H2O2 levels were decreased. None of these drugs had any effect on GR and catalase levels (P > 0.05). Desferrioxamine is useful to prevent cisplatin-induced lipid peroxidation, however, vitamin C and E are more effective on antioxidant enzymes than desferrioxamine.

Animals↗
PubMed1999

Rasmussen encephalitis in childhood.

Six patients admitted to the Department of Pediatric Neurology at Hacettepe University Children's Hospital between 1992 and 1997 with a clinical diagnosis of Rasmussen encephalitis received surgical treatment for their intractable epilepsy. MRI, SPECT and WADA tests were performed in patients with an epileptic focus demonstrated on routine or long-term video EEG monitoring. Viral studies using the PCR methodology were performed in cases with histopathological evidence of Rasmussen encephalitis. The ages of these patients ranged between 7 and 16 years, and the mean age at onset of seizures was 7.1+/-2.2 years. In four patients seizures presented as epilepsia partialis continua and were refractory to anticonvulsive drug therapy. In three cases intravenous immunoglobulin therapy yielded temporary and partial improvement in seizure control. The mean presurgical follow-up duration was 2.04+1.74 years, and early surgical intervention for epilepsy was performed in one case. The surgical approach selected for the treatment of epilepsy was resective surgery with electrocorticography. The mean postoperative follow-up duration was 32.3+17.2 months. Seizures were fully controlled in one patient, in whom surgery was performed 3 months after the seizures first started. Early surgical intervention may provide histopathological evidence for diagnosis as well as effective seizure control.

Child↗
PubMed1992

Novel Tay-Sachs disease mutations from China.

We describe three HEXA mutations associated with infantile Tay-Sachs disease (TSD) in three unrelated nonconsanguineous Chinese families. Novel mutations were found in two of these families. The third is a previously reported mutation (G-->A transition at nt 1444) (Nakano et al., 1988). Direct sequencing of PCR products identified a novel insertion of an A after nt 547 in family 1. This change generates an early termination codon 6 bp downstream from the insertion site. Allele-specific oligonucleotide hybridization confirmed homozygosity in the proband. Single strand conformational polymorphism analysis and direct sequencing of amplified exon 13 revealed a T-->C transition at nt 1453 with the corresponding amino acid substitution W485R in the second family. This mutation creates an Fnu4HI restriction site. The proband is homozygous for this allele. When the site-specific mutagenized alpha cDNA carrying the T-->C transition at nt 1453 was expressed in COS 1 cells hexosaminidase S activity was not detectable above background. A G-->A transition at nt 1444 (exon 13) corresponding to the E482K substitution was found in the third family. This mutation occurs at a CpG dinucleotide. It has been reported in an Italian TSD proband and causes defective intracellular transport of the alpha-subunit from the rough endoplasmic reticulum to the Golgi apparatus.

Animals↗
PubMedDate not supplied

Neutral polymorphisms in the deletion-prone regions of the dystrophin gene.

The single-strand conformational polymorphism technique was used to search for neutral polymorphisms in 18 PCR-amplified dystrophin gene fragments. Out of the seven polymorphisms (six intronic and one exonic) detected in Caucasians, one was absent from the Oriental population. Significant differences in allele frequencies between the two populations were observed for three of the intronic polymorphisms. In Caucasians, one variant position occurred per 728 bp of the total DNA or one per 483 bp of the intronic sequence; the corresponding average heterozygosities were 0.04 and 0.06%, respectively.

Alleles↗
PubMedDate not supplied

Neonatal goiter caused by expectorant usage.

A female newborn was admitted with the symptoms of mild respiratory distress, protruding tongue, hypotonicity, cutis marmorata, sclerema, myxedema, abdominal distension, and feeding problems on the first day of life. She had a huge neck mass, a large anterior and posterior fontanel, and hoarse cry. She had no umbilical hernia or jaundice. A history of maternal potassium iodine (expectorant) usage without doctor's advice was obtained; the mother had not attended a clinic throughout the pregnancy. On ultrasonographic examination, the thyroid right lobe was 53 x 31 mm and the left lobe was 34 x 31 mm. The results of thyroid hormone tests on the first day were as follows: T3 20 ng/dl (normal: 32-216 ng/dl), T4 0.9 microg/dl (11.8-22.6 microg/dl), TSH 120 mIU/l (2.5-13.3 mIU/l). This patient is presented to emphasize the role of hypothyroidism in drug-induced neonatal goiter and to discuss the possibility of a life-threatening effect of congenital goiter, i.e. respiratory tract obstruction.

Expectorants↗
PubMedDate not supplied

Rheumatic heart disease prevalence among schoolchildren in Ankara, Turkey.

Rheumatic heart disease (RHD) continues to be a common health problem in the developing world. Although little longitudinal data are available, evidence suggests that there has been little if any decline in the occurrence of RHD over the past few decades. There are only a few population surveys available in Turkey for prevalence of RHD. This survey was undertaken to estimate its prevalence among schoolchildren and changes over the last 20 years in the capital, Ankara. In Ankara, 4,086 schoolchildren aged between six and 17 years were screened over a period four months (March 1995-June 1995) by the same pediatrician. Forty-eight percent (n = 1,945) were female and 52 percent (n = 2,141) were male. Three children out of 4,086 (0.73 per 1,000) were noted to have findings consistent with RHD. Fifteen children had an episode of rheumatic fever (RF). Cumulative prevalence rate (prevalence rate for RF history) was 3.7 per 1,000. We concluded that RHD prevalence has decreased in Ankara over the last decades.

Adolescent↗
PubMedDate not supplied

Estimation of pulmonary artery pressure by contrast-enhanced Doppler signals and comparison with catheter-measured pressures.

Determination of pulmonary artery systolic pressure (PASP) is essential for the diagnosis, and the timing and type of management of patients with congenital heart disease (CHD). Usually cardiac catheterization, an expensive and invasive technique, is required for accurate measurement. A number of noninvasive methods for the assessment of PASP have been developed, one of which is estimation of PASP using contrast-enhanced tricuspid regurgitation Doppler signals (TRDS). In this study, right ventricular systolic pressures (RVSP) and PASP of 36 patients (19 girls, 17 boys; aged 5 months to 15 years) with CHD were estimated by TRDS before and after galactose solution (GS) and were compared with catheterization measurements. Significant TRDS (> 1 m sec.) were obtained in nine of 36 (25%), patients before GS and in 23 of 36 patients (64%) after GS. TRDS were increased significantly by contrast agent. Estimated RVSP and PASP were significantly different from the measured pressures before and after GS. There were significant correlations between the estimated RVSP and PASP and measured RVSP after GS. Estimated pressures were underestimated. We conclude that it is better to use the estimated PASP on patients with significant TRDS for the classification of PASP.

Adolescent↗