Deamidation in human lens betaB2-crystallin destabilizes the dimer.

Two major determinants of the transparency of the lens are protein-protein interactions and stability of the crystallins, the structural proteins in the lens. betaB2 is the most abundant beta-crystallin in the human lens and is important in formation of the complex interactions of lens crystallins. betaB2 readily forms a homodimer in vitro, with interacting residues across the monomer-monomer interface conserved among beta-crystallins.

GABA(A)-receptor expression in glioma cells is triggered by contact with neuronal cells.

The expression of functional GABA(A)-receptors in glioma cells correlates with low malignancy of tumours and cell lines from glioma lack these receptors. Here we show that contact with neurons induces the expression of functional GABA(A)-receptors. C6 and F98 glioma cell lines were labelled by recombinant expression of enhanced green fluorescent protein injected into rat brain and studied in acute slices after two to three weeks of tumour growth.

Placebo-controlled evaluation of amphetamine mixture-dextroamphetamine salts and amphetamine salts (Adderall): efficacy rate and side effects.

Objective: The primary objective of this study was to determine the efficacy rate of Adderall in children newly diagnosed with attention-deficit/hyperactivity disorder (ADHD). A secondary objective was to address the severity of side effects associated with Adderall treatment in children with ADHD using the Barkley Side Effects Questionnaire (BSEQ).

Design: Randomized, double-blind, placebo-controlled crossover trial.

Stimulant use and the potential for abuse in Wisconsin as reported by school administrators and longitudinally followed children.

The purpose of this study was to describe stimulant use and abuse as reported by school administrators and children diagnosed with attention deficit/hyperactivity disorder or attention deficit disorder inattentive. Five years after being identified as Ritalin responders, 161 children were surveyed regarding stimulant use and abuse. School principals in central Wisconsin were also surveyed regarding stimulant use and policies.

Evidence for a novel gene for familial febrile convulsions, FEB2, linked to chromosome 19p in an extended family from the Midwest.

Febrile convulsions are a common form of childhood seizure. It is estimated that between 2 and 5% of children will have a febrile convulsion before the age of 5. It has long been recognized that there is a significant genetic component for susceptibility to this type of seizure.

Tiagabine for complex partial seizures: a randomized, add-on, dose-response trial.

Objective: To determine the efficacy and tolerability of tiagabine, a new antiepileptic drug (AED) that inhibits gamma-aminobutyric acid (GABA) uptake, at 3 dose levels vs placebo as adjunctive therapy in patients with intractable complex partial seizures (CPS).

Design: Randomized, double-blind, placebo-controlled study with a parallel-group, add-on design, starting with a 12-week unblinded baseline phase followed by a 20-week double-blind treatment phase.

Setting: Twenty-one US medical centers.

Seizure exacerbation and status epilepticus related to carbamazepine-10,11-epoxide.

Over a 3-year period, we encountered 6 adults whose seizure control unexpectedly deteriorated with the occurrence of partial status epilepticus and daily multiple seizures. Analysis of the case histories and subsequent clinical follow-up for 1 1/2 to 3 years disclosed the following evidence that demonstrates the role of carbamazepine-epoxide in the development of the seizure exacerbation: (1) There were high serum carbamazepine-epoxide concentrations while serum carbamazepine concentrations were lower than or the same as baseline levels; (2) all patients were taking drugs that are known to increase serum carbamazepine-epoxide concentrations; (3) status epilepticus failed to respond to intravenous phenytoin loading; (4) seizure exacerbation in all patients was corrected by withholding carbamazepine dose; (5) seizure exacerbation recurred in 1 patient who resumed the same dose of carbamazepine; and (6) there were no prior status epilepticus or daily multiple seizures despite previous toxicities with other antiepileptic drugs in 3 patients. Our experience shows that inconspicuous elevation of carbamazepine-epoxide levels during polytherapy may precipitate a distinct state of drug toxicity characterized by severe exacerbation of seizures.

Yield of sphenoidal recording in sleep-deprived outpatients.

We retrospectively reviewed the results of sphenoidal recordings performed after sleep deprivation in 101 consecutive outpatients whose prior scalp EEGs failed to show epileptiform discharges (EDs). These patients were suspected of having seizures of temporal lobe origin. Blinded reviews of the recordings by two electroencephalographers showed a tendency for sphenoidal recording to detect EDs at a higher rate than scalp recording, but the difference did not reach statistical significance (p = 0.

Prognosis of photoparoxysmal response in nonepileptic patients.

Photoparoxysmal response (PPR) is sometimes incidentally encountered in EEGs performed for evaluation of nonepileptic symptoms. We conducted the first long-term study of a cohort of nonepileptic patients to determine their risk of having seizures subsequent to incidental recording of PPR. After 6 to 12 years (mean, 9 years), none of the 33 patients had had epileptic seizures.

Placebo-controlled evaluation of Ritalin side effects.

Objective: To address the frequency of side effects of Ritalin therapy in children with attention deficit hyperactivity disorder (ADHD) using the Barkeley Side Effects Questionnaire (BSEQ) in a clinical setting.

Design: Randomized double-blind placebo-controlled cross-over trial.

Setting: A large rural tertiary care clinic.

Posthemorrhagic hydrocephalus in high-risk preterm infants: natural history, management, and long-term outcome.

The natural history, medical management, and outcome in infants with progressive posthemorrhagic hydrocephalus after intraventricular hemorrhage were studied prospectively. Infants with asymptomatic severe posthemorrhagic hydrocephalus were managed with a predetermined protocol. Outcome between groups at 1 to 2 years and at more than 3 years was compared.

Neurologic outcome following pediatric resuscitation.

This study reports the survival rate and short-term neurologic outcome of children who sustained cardiac arrests at Henrietta Egleston Hospital for Children, a pediatric teaching hospital. A commonly held belief in pediatric centers has been that children tolerate the insult of cardiac arrest better than adults. Cardiac arrest was defined as the need for external or internal cardiac compressions.

Brain death in children: characteristic common carotid arterial velocity patterns measured with pulsed Doppler ultrasound.

The clinical criteria for brain death in children remain controversial. An accepted confirmatory test for brain death is the documented absence of intracranial blood flow, the most common methods being arteriography and radionuclide cerebral angiography. We correlated the common carotid arterial blood velocity patterns measured by pulsed Doppler ultrasound in 32 brain-dead infants and children with results of their clinical examinations and, whenever possible, with radionuclide cerebral angiography.

MR of Leigh's disease (subacute necrotizing encephalomyelopathy).

MR images of three patients with Leigh's disease (subacute necrotizing encephalomyelopathy) were compared with CT findings. In all patients typical lesions in the basal ganglia were identified with both MR and CT. In two patients MR permitted identification of additional lesions not detected with CT.

Breath amplitude modulation of heart rate variability in normal full term neonates.

The relationship between heart rate variability and respiration patterns was investigated using spectral analysis techniques in nine full-term infants whose ages ranged from 39-75 h. All the infants were studied during sleep, although no attempt was made to classify rapid eye movement or nonrapid eye movement states prospectively. The data obtained were examined to determine which aspects of neonatal breathing patterns are correlated with heart rate variability.

Platelet-monoamine oxidase activity in Reye's syndrome.

Platelet and liver monoamine oxidase (MAO) activity (mean +/- SD) was evaluated in patients with liver-biopsy-proven Reye's syndrome. MAO was measured by a radioenzymatic technique with [3H]tyramine as a substrate. A marked decrease in MAO activity [3.

Hypercatecholaminemia in Reye's syndrome.

To evaluate the role of catecholamines in Reye's syndrome, a specific and sensitive radioenzymatic assay was used to study plasma and CSF concentration of dopamine, norepinephrine, and epinephrine in 14 patients with liver-biopsy-proven Reye's syndrome. The results (median and range) revealed significant (P less than .04, P less than .

Relationship between pressure passivity and subependymal/intraventricular hemorrhage as assessed by pulsed Doppler ultrasound.

A prospective study was undertaken using a range-gated, pulsed Doppler velocimeter to study flowpressure relationships in the anterior cerebral artery. Serial velocity and pressure studies were performed with each infant serving as his or her own control. The hypothesis tested was that ill preterm infants sustaining subependymal/intraventricular hemorrhage would have absent autoregulation.

Abnormal regulation of pyridoxal 5'-phosphate in Reye's syndrome.

Seeking to determine the effect of liver disease associated with Reye's syndrome on the regulation of plasma pyridoxal 5'-phosphate, we measured this compound in plasma from 11 patients with biopsy-proven Reye's syndrome. Its concentrations in plasma are significantly higher [37.5 (SD 6.

Range-gated pulsed Doppler ultrasonographic evaluation of carotid arterial blood flow in small preterm infants with patent ductus arteriosus.

Range-gated pulsed Doppler (RGPD) ultrasonography was utilized to study the effect of a patent ductus arteriosus (PDA) on carotid arterial blood flow in small preterm infants. Carotid arterial flow velocity studies were performed on 23 preterm infants, sampling right and left carotid arteries. Studies on seven infants after PDA ligation and on seven who developed no evidence of PDA were used as controls.