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S Harel

Publications and source records attributed to S Harel.

At least 19 recordsLinked to original sources
PubMed2006

Tyrosine kinase B receptor and its activated neurotrophins in ovaries from human fetuses and adults.

The signals initiating the growth of primordial follicles are unknown. Growth factors such as neurotrophin 4/5 (NT-4/5) and brain-derived neurotrophic factor (BDNF) may play a role in this process. To investigate the expression of NT-4/5 and BDNF and their receptor tyrosine kinase B (TrkB) in the early developing follicles, we fixed and froze 12 ovarian samples from adolescents/adults and 31 ovaries from human fetuses. The fixed samples were prepared for immunohistochemical staining for NT-4/5, BDNF and the TrkB receptor. Total RNA was extracted from the frozen ovarian samples, and the expression of NT-4/5, BDNF and the TrkB receptor (full length and two truncated isoforms) was investigated by RT-PCR. Products were resolved by 1% agarose gel electrophoresis and image analysis. Immunohistochemical staining revealed the expression of NT-4/5 and BDNF mainly in oocytes and, in a minority of samples, also in the granulosa cells (GCs); TrkB receptor was identified in oocytes and GCs. Transcripts of NT-4/5, BDNF and all forms of TrkB receptor were identified in the samples. To elucidate whether indeed NT-4/5 and BDNF are involved in growth initiation of human primordial follicles, they should be added to the culture medium.

Adolescent↗
PubMed2005

Deficits in spatial orientation of children with intrauterine growth retardation.

The spatial orientation of intrauterine growth retarded (IUGR) children versus age-matched controls was examined using two spatial tests. The first test was the radial arm maze (RAM), a navigational test frequently used in animal models. The second test was a subtest from the Kaufman assessment battery for children (K-ABC). The IUGR group comprised 28 children aged 6 years. The control group comprised 29 appropriate-for-gestational age children. The performance of the IUGR children was significantly inferior to controls in both tests. In the RAM test, the ratio between the correct entrances to the total entrances was significantly lower in the IUGR group than in the control group (P<0.001). In the K-ABC, the IUGR group could not perform as well as control children (P<0.001). These results suggest that spatial orientation in IUGR children is inferior to their age-matched controls, possibly contributing to their potential learning difficulties. The present results also suggest that the RAM can be potentially used to test spatial orientation of children at-risk.

Child↗
PubMed2001

Worster-Drought and congenital perisylvian syndromes-a continuum?

A 5-year-old female was evaluated because of severe speech and expressive language delay. On examination, she could hardly speak and communicated through gestures. She manifested severe dysarthria and difficulty in protruding and moving her tongue laterally. She lacked coordination of the swallowing process, with drooling and an increased mental reflex. Her cognitive development was normal, and no associated neurologic dysfunction of the limbs was noted. On follow-up, the child experienced two episodes of seizures at 6 years of age. Magnetic resonance imaging of the brain demonstrated perisylvian and frontal polymicrogyria. Clinical and radiologic findings demonstrated a similarity and continuum between congenital suprabulbar paresis (Worster-Drought syndrome) and perisylvian syndrome.

Bulbar Palsy, Progressive↗
PubMed2001

Betalains--a new class of dietary cationized antioxidants.

Antioxidant nutrients from fruits and vegetables are believed to be a class of compounds that exert their effects in humans by preventing oxidative processes which contribute to the onset of several degenerative diseases. This study found a new class of dietary cationized antioxidants in red beets (Beta vulgaris L.). These antioxidants are betalains, and the major one, betanin, is a betanidin 5-O-beta-glucoside. Linoleate peroxidation by cytochrome c was inhibited by betanin, betanidin, catechin, and alpha-tocopherol with IC(50) values of 0.4, 0.8, 1.2, and 5 microM, respectively. In addition, a relatively low concentration of betanin was found to inhibit lipid peroxidation of membranes or linoleate emulsion catalyzed by the "free iron" redox cycle, H(2)O(2)-activated metmyoglobin, or lipoxygenase. The IC(50) inhibition of H(2)O(2)-activated metmyoglobin catalysis of low-density lipoprotein oxidation by betanin was <2.5 microM and better than that of catechin. Betanin and betanidin at very small concentrations were found to inhibit lipid peroxidation and heme decomposition. During this reaction, betanidin was bleached completely, but betanin remained unchanged in its absorption. This difference seems to derive from differing mechanisms of protection by these two compounds. The high affinity of betanin and betanidin for membranes was demonstrated by determining the rate of migration of the compounds through a dialysis tube. Betanin bioavailability in humans was demonstrated with four volunteers who consumed 300 mL of red beet juice, containing 120 mg of the antioxidant. The betacyanins were absorbed from the gut and identified in urine after 2-4 h. The calculated amount of betacyanins found in the urine was 0.5-0.9% of that ingested. Red beet products used regularly in the diet may provide protection against certain oxidative stress-related disorders in humans.

Animals↗
PubMed2001

Transient oromotor deficits in children with benign childhood epilepsy with central temporal spikes.

PURPOSE: To describe transient oromotor deficits in benign childhood epilepsy with centrotemporal spikes (BCECTS), an idiopathic age-specific epileptic syndrome with a benign course. METHODS: Five children with BCECTS and intermittent dysarthria and drooling not in the context of typical clinical seizures are presented. RESULTS: The periods of oromotor deficits correlated with increased seizure frequency in all children. Concomitant EEGs that were recorded during periods of dysarthria in four of the children revealed focal electrographic seizures. The reported children did not differ from other patients with BCECTS in any other respect. CONCLUSIONS: Transient oromotor dysfunction is a rare ictal phenomenon that occurs in children with BCECTS with no other unique clinical features.

Adolescent↗
PubMed2001

No evidence of epilepsy following endoscopic third ventriculostomy: a short-term follow-up.

Patients with ventriculo-peritoneal shunts are predisposed to various complications, including the appearance of seizures over time. The high rate of complications prompted an interest in alternative procedures such as endoscopic third venticulostomy (ETV) in selected patients. From 1996 to 1998, 42 patients underwent ETV in our center. Of the 27 operated children who were followed for an average of 32 months, none experienced seizures during that time. We conclude that, in addition to other benefits, ETV minimizes the risk of epilepsy following shunt insertion, probably due to the lack of direct cortical insult.

Child↗
PubMed2001

Prognostic significance of hyperechogenic lesions in the basal ganglia and thalamus in neonates.

Neonatal cranial ultrasonography at times reveals hyperechogenic lesions in the basal ganglia and thalamus. These lesions have been attributed to a wide variety of pathologic states, among them toxoplasmosis, rubella, cytomegalovirus, and herpes simplex (TORCH) infections, chromosomal abnormalities, and asphyxia. The clinical significance in terms of the neurodevelopmental outcome of this radiologic abnormality is unknown. We performed a developmental evaluation on 16 children aged 2 to 6 years in whom neonatal cranial ultrasonography had demonstrated hyperechogenic lesions in the basal ganglia or thalamus and had no other neurodevelopmental risk factors. There was no significant difference between the average Developmental Quotient of the target population and the normal population in regard to developmental status. We conclude that in our population, an isolated finding of hyperechogenic lesions in the basal ganglia is probably not a predictor of poor neurodevelopmental outcome.

Basal Ganglia↗
PubMed2001

Blood pressure values in children with intrauterine growth retardation.

BACKGROUND: Low birth weight has been shown to be strongly related to hypertension in adult life. OBJECTIVES: To determine whether blood pressure is higher in children with intrauterine growth retardation than in control subjects. METHODS: Blood pressure was measured in 58 children aged 4-6 years with IUGR and in 58 age-matched controls. The control children, whose birth weight was appropriate for gestational age, were also matched for gestational age. RESULTS: The children with IUGR had significantly higher mean values of systolic (P < 0.05) and diastolic blood pressures (P < 0.05) and mean arterial pressure (P < 0.05). Significant differences in blood pressure values were found between preterm IUGR (n = 21) and preterm controls (P < 0.05). CONCLUSIONS: These data indicate that children with IUGR may be at higher risk of hypertension already in childhood.

Blood Pressure↗
PubMed2000

Experimental intrauterine growth retardation alters renal development.

Vascular placental insufficiency is considered a common pathogenic factor in human intrauterine growth retardation (IUGR), resulting in small-for-gestational-age, asymmetric newborns. IUGR neonates experience higher morbidity and mortality rates, as well as a possible contribution towards late sequelae, such as hypertension, and cardiovascular disease in adulthood. To simulate vascular placental insufficiency, an experimental rabbit IUGR model was used. Intrauterine growth retardation was achieved by ligation of 25-30% uteroplacental vessels of half of the fetuses during the last third of gestation. Ischemic fetuses were significantly small, asymmetric, and had a disproportionately small body with a relatively large head. The kidneys from all groups were analyzed for relative estimated glomeruli number (REGN) using an unbiased blind design. The glomeruli number was significantly reduced in the asymmetric IUGR rabbit fetuses, probably due to decreased renal vascular supply. Our results support the concept that the reduced number of glomeruli may contribute to impaired renal function, thus predisposing to neonatal renal dysfunction and late sequelae, such as adult hypertension. This study emphasizes the clinical importance of early IUGR diagnosis and prevention.

Animals↗
PubMed2000

Unprovoked seizures after complex febrile convulsions.

Children with complex febrile convulsions bear a higher risk of developing epilepsy than children with simple febrile convulsions. Complex febrile convulsions are defined by the presence of prolonged seizures, partial seizures and multiple seizures occurring during the same day. The aim of this study is to delineate the relative significance of each of the three criteria defining complex febrile convulsions. Fifty-seven out of 477 children (12%) admitted for febrile convulsions had complex febrile convulsions and normal neurological examination. Follow-up was available for 48 (84%) of them. Thirteen of these 48 (27%) had epilepsy at follow-up. The mean age of seizure onset among the patients with subsequent afebrile seizures was significantly lower than the rest (10.8 months versus 16.8 months). The patients with partial febrile convulsions showed a trend toward a higher risk (45%) of developing epilepsy than the patients with multiple febrile convulsions (21%).

Child↗
PubMed2000

Mental retardation subsequent to refractory partial seizures in infancy.

Whether seizures are the direct cause of cognitive deterioration in epileptic children is undetermined. This retrospective study aimed to delineate a subgroup of pediatric patients with cognitive deterioration and refractory seizures in the absence of recognized causes for mental retardation. Of the 80 children identified as having mental retardation and refractory seizure disorder, seven (8.7%) had normal cognitive development until at least 1 year of age. Their metabolic status was normal. Five of them suffered repeated frequent partial seizures with onset in the first year of life and two had repeated episodes of status epilepticus. All seven had similar characteristics of early onset partial seizures, six of them had partial seizures secondarily generalized and one had complex partial seizures. The time of peak cognitive deterioration correlated with increases in seizure frequency during that period. Evaluation revealed a well-defined epileptic focus in the absence of neuroimaging abnormality except for hippocampal atrophy in the two children with complex partial seizures and a small vascular malformation in one child. Uncontrolled partial seizures in the first months of life may result in cognitive deterioration.

Adolescent↗
PubMed2000

Neurologic presentations of mitochondrial disorders.

This article describes the neurologic presentations of children with mitochondrial disorders. The charts of 42 children with highly suspect mitochondrial disorders were reviewed. Thirty-seven children were diagnosed as having definite mitochondrial disorders based on a suggestive clinical presentation and at least one accepted criteria, while in five patients the diagnosis remained probable. All patients had nervous system involvement, but it was the presenting symptom in 28 of 42. Eighteen children had normal intelligence and 24 had mental retardation or developmental delay at the onset of their disease. Twenty-five patients had either an acute regression or a progressive encephalopathy. The most frequent neurologic manifestations were abnormal tone, seizures, extrapyramidal movements, and autonomic dysfunction. The eyes were involved in 11 children. Nerve deafness was found in seven patients. Myopathy was found in only six patients. In conclusion, a complex neurologic picture, especially with other organ involvement, warrants a full mitochondrial evaluation.

Brain Diseases, Metabolic, Inborn↗
PubMed2000

Alternating hemiplegia of childhood in half-sisters.

We present the family of two girls affected with alternating hemiplegia of childhood who were born to the same mother and different fathers. Previous reports suggested mitochondrial dysfunction as an etiologic mechanism for this disorder. Muscle biopsy, including a measurement of the respiratory chain enzymes, performed in one of the sisters showed no mitochondrial abnormalities. The mode of inheritance is not certain, but an autosomal-dominant gene is most likely.

Adolescent↗
PubMed2000

Methylenetetrahydrofolate reductase deficiency: importance of early diagnosis.

Methylenetetrahydrofolate reductase deficiency is the most common inborn error of folate metabolism and should be suspected when homocystinuria is combined with hypomethioninemia. The main clinical findings are neurologic signs such as severe developmental delay, marked hypotonia, seizures, microcephaly, apnea, and coma. Most patients present in early life. The infantile form is severe, with rapid deterioration leading to death usually within 1 year. Treatment with betaine has been shown to be efficient in lowering homocysteine concentrations and returning methionine to normal, but the clinical response is variable. We report two brothers with methylenetetrahydrofolate reductase deficiency: the first was undiagnosed and died at 8 months of age from neurologic deterioration and apnea, while his brother, who was treated with betaine from the age of 4 months, is now 3 years old and has developmental delay.

Betaine↗
PubMed2000

Six-year follow-up of children with intrauterine growth retardation: long-term, prospective study.

This prospective study was designed to characterize the neurodevelopmental and cognitive difficulties specific to children with intrauterine growth retardation and to detect early clinical predictors of these difficulties. Eighty-one children with intrauterine growth retardation were monitored up to 6 to 7 years of age using biometric parameters, perinatal risk questionnaires, and detailed neurodevelopmental and cognitive assessments. Forty-one children served as age-matched, appropriate for gestational age controls. A significant difference in growth parameters (P < .001), neurodevelopmental score (P < .05), and IQ (P < .05) was found between the children with intrauterine growth retardation and controls. A specific profile of difficulties in coordination, lateralization, spatial and graphomotor skills, and abundance of associated movements is typical of the children with intrauterine growth retardation and hints at possible later learning disabilities. The clinical parameters best predicting neurodevelopmental outcome were the neonatal risk score (P < .05) and the weight and height at 6 years of age (P < .05). The children with intrauterine growth retardation with neonatal complications had lower neurodevelopmental scores than the controls but no difference in IQ. Intrauterine growth retardation children diagnosed prenatally had the same neurodevelopmental and IQ scores as those diagnosed at birth, probably due to the careful perinatal and obstetric care provided. Children with intrauterine growth retardation demonstrate a specific profile of neurodevelopmental disabilities at preschool age. Early diagnosis and intervention could probably reduce these difficulties to a minimum.

Child↗