PubMed Health⌕ Search

Biomedical subjects

U Kramer

Publications and source records attributed to U Kramer.

At least 37 records · Page 2Linked to original sources

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↗

Characterization and comparison of autistic subgroups: 10 years' experience with autistic children.

To summarize our 10-year experience with autistic children at the Tel Aviv Child Development Center, the files of all 55 children with autism treated at our center over a 10-year period were retrospectively reviewed. Particular attention was addressed to the value of the medical work-up in detecting the etiology of autism and to factors differentiating infantile autism (IA) from autistic-like behavior (ALB). Twenty-four subjects (44%) had IA and 31 (56%) had ALB. These subgroups were compared for demographic, perinatal, familial, neurological, and psychological findings, and outcome at discharge. Associated medical conditions and the yield of metabolic work-up and neuroimaging and electroencephalography studies are discussed. The two subgroups differed only in severity of autistic symptoms and cognitive function (P<0.05), but not in demographic or neurobiological findings. It was concluded that IA and ALB are similar conditions, and autism has a wide continuum of clinical expressions.

Autistic Disorder↗

Epilepsy in the first year of life: a review.

The prevalence of epilepsy is highest during the first year of life. Approximately 50% of patients with seizure onset between 1 and 12 months of age suffer from West syndrome. The rest have one of 12 well-delineated epilepsy syndromes, or in most cases have what are classified as generalized or partial seizures. The outcome of infants with partial seizures is significantly worse than that of patients with generalized seizures. This is true not only for symptomatic partial seizures but also for a subgroup of infants with cryptogenic partial seizures.

Cross-Sectional Studies↗

SMA type 2 unrelated to chromosome 5q13.

We describe two brothers with clinical and histological findings of type 2 spinal muscular atrophy (SMA) associated with small head circumference (<2%) and normal cognitive development. No survival motor neuron (SMN) or neuronal apoptosis-inhibitory protein (NAIP) deletions were detected in these sibs, and they were discordant for the haplotypes determined by DNA markers flanking the 5q13 SMA locus. These findings support the presence of a distinct anterior horn disease unrelated to 5q13. This entity may have either autosomal recessive or X-linked inheritance.

Child, Preschool↗

Electroencephalographic discharges of temporal lobe seizures in children and young adults.

We investigated the discharge morphology and propagation patterns of electroencephalographic seizures of temporal lobe onset in 21 children and young adults who underwent invasive long-term EEG monitoring (LTM). Of those, 15 subsequently underwent anterior temporal lobectomy. The onset was focal in 63%. The most frequent discharge morphology was low amplitude beta (30%) or rhythmic/semirhythmic theta discharge (30%). Thirteen patients displayed several sequences of propagation with different spreading stages along a fixed path. Initial spreading to the ipsilateral frontal lobe was associated with a higher frequency of secondary generalization than initial spreading to the contralateral temporal lobe (P = 0.18). A comparison of 13 patients older than 18 years of age with 8 patients younger than 14 years showed a trend towards a lower rate of propagating from the temporal lobe (P = 0.13) in the younger age group. Discharge morphology was not correlated with age, focality, or outcome of surgery.

Adolescent↗

Epidemiology of epilepsy in childhood: a cohort of 440 consecutive patients.

This study analyzes the relative frequency and age of onset of the different seizure types in a 20-year cohort of a pediatric neurology outpatient clinic of an urban hospital that serves the majority of the city's population (Tel Aviv Medical Center). Only patients with two or more unprovoked seizures were included. Neonatal seizures were excluded from the analysis. The different seizure types in descending order of frequency were: partial seizures secondarily generalized (20.6%), complex partial seizures (12.5%), West syndrome (9%), simple partial seizures (8.6%), benign rolandic epilepsy of childhood (8%), absence seizures (7%), generalized tonic-clonic seizures (6.6%), generalized tonic seizures (5%), myoclonic seizures (2.2%), benign occipital epilepsy of childhood (2%), mixed type seizures (1.8%), Lennox-Gastaut syndrome (1.5%), juvenile myoclonic epilepsy (0.9%), atypical absence (0.6%), Landau-Kleffner syndrome, Ohtahara syndrome, myoclonic astatic epilepsy, electrical status epilepticus in sleep and startle epilepsy (0.2% each), and unclassified seizures (12%). The findings of this study confirm that there are more pediatric patients with partial seizures (52%) than primary generalized seizures (33%) and that partial seizures secondarily generalized is the most frequent seizure type in this age group.

Adolescent↗

Neuroimaging of children with partial seizures.

The predictive value of abnormal neurological findings on neuroimaging (NI) of children with partial seizures (PS) was studied. The sample comprised 143 children and adolescents with PS from 1979 to 1996. Fifty patients had the following abnormal NI findings: diffuse atrophy and porencephalic cyst (5.6% each), hemiatrophy, tumors, neurocutaneous syndrome brain lesions, and dysgenesis (4.2% each), and arachnoid cyst and hydrocephalus (2.1% each). There were significantly more NI abnormalities among those with simple PS than among the other groups of complex PS or PS with secondary generalization. All cases of porencephalic cyst (n = 8), and hemiatrophy (n = 6) were in the hemiparetic group, all cases of tumor (n = 6) were in the normal group, while most cases of diffuse atrophy were in the mentally retarded group. Patients with abnormal NIs had a significantly earlier age of seizure onset than the others. The chance of finding a treatable abnormality in neuroimaging was 5% for tumors and 2% for arachnoid cysts in the group of patients with PS and normal neurological findings. Neither an abnormality detected in a neurological examination nor the type of seizure are predictive parameters for suggesting the presence of a resectable brain tumor. All patients with newly diagnosed PS should undergo an MRI.

Adolescent↗

Generalized tonic and tonic-clonic seizures of childhood.

In a retrospective analysis of all our patients with seizure onset prior to age 16 years, 25 patients with primary generalized tonic (n = 10) or tonic-clonic (n = 15) seizures were identified. These patients constituted 5.7% of the total seizure patient population in our institute between the ages of 1 month and 16 years. The natural history of generalized tonic-clonic seizures is known to be benign; however, that of isolated primary generalized tonic seizures is not clear. Therefore, an attempt was made to characterize the patients suffering from primary generalized tonic seizures and determine their outcome. Analysis of our patient population shows that both seizure types are characterized by early onset of generalized seizures that appear in normally developed children with a normal electroencephalographic background. The children usually respond quickly to antiepileptic drugs. A long-term follow-up (mean period of 7.6 years) was possible in 84% of the patients, and showed that 95% of them were seizure free at the end of the follow-up period. There was no significant difference between the two groups in regard to age of onset, family history, and seizures at follow-up. In conclusion, the natural history of patients with generalized tonic seizures is similar to the benign course of those with generalized tonic-clonic seizures.

Adolescent↗

[Ceramic cups for hip endoprostheses. 5: Consideration of designs].

Using the combination ceramic on ceramic for hip prostheses, the wear rate can be reduced to less than 1 micron per million cycles. More than 20 years of experience are now available for various concepts involving alumina ceramics in THR. In the early days, monolithic ceramic cups were employed. However, since alumina ceramic has an unsatisfactory potential for bone integration, soft tissue forms at the interface, with the result that the sockets migrate and penetrate. To improve bony integration, monoblock cups surfaced with ceramic beads were introduced. For the past 10 years, there has been a trend towards the use of modular acetabular components comprising a metal shell and a liner made of Biolox forte ceramic. Two concepts for the fixation of the ceramic liners are employed: locking of the ceramic in the metal shell (CeraLock) and the sandwich concept with a polyethylene layer interposed between liner and shell. The basic design and important aspects such as diameter, range of motion, and the possibility for revision, clinical experience, and trends are discussed.

Ceramics↗

Focal features in West syndrome indicating candidacy for surgery.

A subgroup of patients with West syndrome (WS) also have focal features, and some of these patients respond to surgical intervention. To determine the incidence of focal features in patients with WS and to establish the correlation of these features with outcome, all patients with WS treated in the Epilepsy Unit of the Children's Hospital (Boston, MA) during the years 1989 to 1992 were retrospectively evaluated. Focal features included partial seizures, hemiparesis, focal radiologic findings, asymmetric spasms, and lateralized hypsarrhythmia. The different focal features were later correlated with the natural history of the disease. Sixty-seven patients were included in the study. Sixty-six percent had asymmetric manifestations. Asymmetric spasms, hemihypsarrhythmia, and partial seizures combined with infantile spasms had significant association with asymmetric brain pathology. Focal features did not correlate with age of onset and outcome, but were associated with etiology. Eight of the nine patients who underwent epilepsy surgery had at least two focal features or more. Two of the operated children had focal features in the absence of magnetic resonance imaging abnormalities, thus indicating the necessity for positron emission tomography, the results of which justified surgery.

Brain↗

Clinical characteristics of complex partial seizures: a temporal versus a frontal lobe onset.

The site of origin of complex partial seizures (CPS) is predominantly in the temporal lobe, but frontal, parietal, and occipital lobes may also be involved. In order to correlate clinical behaviours with either a temporal or frontal site of origin, we analysed 211 seizures occurring during invasive monitoring in 26 patients with temporal lobe epilepsy (TLE) and in eight patients with frontal lobe epilepsy (FLE). Although leg movements, defined as thrashing, pedalling and kicking, hand posturing, facial twitching, sitting up, and tonic-clonic movements occurred more frequently in FLE, and hand automatisms were more frequent in TLE, no statistically significant difference was found between the two groups. When analysing only electrographic seizures that did not spread or propagated only to homologous controlateral lobes, leg movements and hand posturing were seen only with FLE, and oral automatisms only in TLE. Seizures of temporal lobe origin were longer in duration and had a higher frequency of auras. We therefore conclude that the reliability of clinical behaviour alone to predict the site of origin of an epileptic discharge is limited when the surface EEG is equivocal or the neuroradiologic evidence of a focus is not clear.

Adolescent↗

A family with hemiplegic migraine and focal seizures.

Familial hemiplegic migraine is a distinctive form of migraine with autosomal dominant inheritance. The patients undergo attacks of migraine complicated by hemiplegia. Seizures have not been reported as comprising a part of this syndrome. We describe three generations of a family with hemiplegic migraine and focal seizures occurring concurrently with the migrainous attacks. There were five affected family members whose clinical features included unilateral headache and transient hemiplegia. Two family members also had focal seizures during the migrainous attacks. One of the patients was treated with carbamazepine with good results. The only associated neurological finding was ataxia which was found in the oldest patient. The presence of focal seizures during an episode of hemiplegic migraine suggests that the two phenomena of migraine and focal seizures may share the same underlying pathophysiology.

Adolescent↗

Outcome of seizures in the first year of life.

AIM: To determine the frequency and natural history of seizures having an onset during the first year of life. METHODS: A retrospective analysis of the files of all patients treated in the paediatric neurology clinic of our medical centre during 1975-1995. RESULTS: Of our 482 patients with seizure onset prior to age 16 years, the first seizure occurred at age 1-12 months in 80 (16.6%). Of those, 38 (48%) had West syndrome and the rest were classified as follows--partial seizures with or without secondary generalization: 19%, generalized tonic seizures: 8.5%, generalized tonic-clonic seizures: 7.5%, myoclonic: 7.5%, unclassified: 7.5%, and mixed-type seizures: 2%. Follow-up was possible in 91% of the patients. Mean follow-up period from seizure onset was 10 years. Of the non-West syndrome patients who were followed, 19 (50%) were still experiencing seizures at follow-up. Eleven of the 15 patients (73%) with partial seizures and four of the 13 patients (31%) with generalized tonic or tonic-clonic seizures had symptomatic seizures. Of the 14 followed patients with partial seizures, 10 (71%) still had seizures at follow-up, as did three (25%) of the 12 followed patients with generalized tonic or tonic-clonic seizures (p = 0.023). CONCLUSIONS: The partial seizures were most often symptomatic with unfavourable prognosis, while the generalized seizures were either symptomatic and severe or cryptogenic and rapidly responsive to anti-epileptic drugs with good outcome.

Adolescent↗

L-type calcium channels in insulin-secreting cells: biochemical characterization and phosphorylation in RINm5F cells.

Opening of dihydropyridine-sensitive voltage-dependent L-type Ca2+-channels (LTCCs) represents the final common pathway for insulin secretion in pancreatic beta-cells and related cell lines. In insulin-secreting cells their exact subunit composition is unknown. We therefore investigated the subunit structure of (+)-[3H]isradipine-labeled LTCCs in insulin-secreting RINm5F cells. Using subunit-specific antibodies we demonstrate that alpha1C subunits (199 kDa, short form) contribute only a minor portion of the total alpha1 immunoreactivity in membranes and partially purified Ca2+-channel preparations. However, alpha1C forms a major constituent of (+)-[3H]isradipine-labeled LTCCs as 54% of solubilized (+)-[3H]isradipine-binding activity was specifically immunoprecipitated by alpha1C antibodies. Phosphorylation of immunopurified alpha1C with cAMP-dependent protein kinase revealed the existence of an additional 240-kDa species (long form), that remained undetected in Western blots. Fifty seven percent of labeled LTCCs were immunoprecipitated by an anti-beta-antibody directed against all known beta-subunits. Isoform-specific antibodies revealed that these mainly corresponded to beta1b- and beta3-subunits. We found beta2- and beta4-subunits to be major constituents of cardiac and brain L-type channels, respectively, but not part of L-type channels in RINm5F cells. We conclude that alpha1C is a major constituent of dihydropyridine-labeled LTCCs in RINm5F cells, its long form serving as a substrate for cAMP-dependent protein kinase. beta1b- and beta3-Subunits were also found to associate with L-type channels in these cells. These isoforms may therefore represent biochemical targets for the modulation of LTCC activity in RINm5F cells.

Calcium Channels↗