Risk of coeliac disease in children of patients and effect of HLA genotype.

Among 73 offspring of parents with coeliac disease, 4 were affected, including 1 in whom the diagnosis was made as a result of the study. The coeliac parents of all 4 were HLA-B8 positive, but 1 affected child had failed to inherit his affected parent's B antigen. The findings are consistent with the hypothesis that an allele affecting liability to coeliac disease is in linkage disequilibrium with HLA-B8.     

Effect of metoclopramide and domperidone on aldosterone, 18-hydroxycorticosterone and prolactin secretion in the rhesus monkey

This study was designed to investigate dopaminergic mechanisms in the control of corticosteroid secretion. Eight rhesus monkeys received metoclopramide (200 μg/kg) or domperidone (200 and 400 μg/kg) with 5% dextrose (vehicle), or with dopamine (4 μg/kg/min) infusions begun 60 min before administration of the dopamine antagonist. Metoclopramide, in the presence of vehicle, increased plasma aldosterone concentrations from 4.8 ± 0.6 ng/dl to a maximum of 36 ± 4.7 ng/dl and PRL concentrations from 7.6 ± 1.1 ng/ml to a maximum of 120.5 ± 8.0 ng/ml. Administration of metoclopramide resulted in a rise in plasma 18-hydroxycorticosterone from 10.2 ± 1.3 ng/dl to a maximum concentration of 49.6 ± 4.5 ng/dl. Plasma concentrations of electrolytes, PRA, plasma cortisol, 11-deoxycorticosterone, corticosterone, 18-hydroxy-11-deoxycorticosterone, were not altered by metoclopramide. Domperidone, in both doses, markedly increased plasma PRL concentrations but had no effect on plasma 18-OHB or aldosterone concentrations. Dopamine infusion inhibited the aldosterone response to metoclopramide and the prolactin response to metoclopramide and domperidone. The results of this investigation demonstrate that aldosterone responses to metoclopramide and prolactin responses to metoclopramide and domperidone, are mediated by their antagonist activity at dopamine receptors.     

Experimental Febrile Convulsions in Epileptic Chickens: The Anticonvulsant Effect of Elevated γ-Aminobutyric Acid Concentrations

The high seizure susceptibility in epileptic chickens is due to an autosomal recessive mutation. In 3-day-old chicks homozygous for the epilepsy gene (epileptics), elevation of body temperature using microwave diathermy evoked an initial febrile seizure resembling the clonic seizures evoked in epileptic chicks by photic stimulation. After complete recovery, this was followed by a clonic-tonic seizure. In nonepileptic heterozygote hatchmates (carriers) of the same age, only the latter seizure pattern was observed. In 16- to 17-day-old chicks of either phenotype, both seizure patterns were observed during hyperthermia. In all cases, the temperature at which seizures occurred was significantly lower in epileptic than in nonepileptic chicks, indicating a lower threshold for febrile seizures when there is an inherited predisposition to convulse. The occurrence of seizures was dependent on the body temperature and not on the rate of rise of temperature. Elevation of the brain gamma-aminobutyric acid (GABA) concentrations by administration of the GABA transaminase inhibitor gamma-vinyl GABA reduced the incidence of the initial febrile seizures and increased the latency in those birds that were not fully protected.     

Current Status of Therapeutic Apheresis in Rheumatoid Arthritis

Evidence developed over the years has suggested that lymphocyte depletion and removal of plasma factors can ameliorate rheumatoid arthritis. In our studies of 40 patients, a subset of patients that respond best to 20 therapeutic lymphaplasmapheresis over 11 weeks has emerged. These are functional Class III patients with seropositive, erosive progressive disease who have little deformity. They must be on long-acting agents or cytotoxic drugs during pheresis to prevent antibody rebound. Other studies have since confirmed our work. The major side effects of pheresis are elucidated. Technologic developments will enable selective pheresis procedures to be in widespread use within a few years.     

Dopamine release and synthesis in the neurointermediate lobe of the rat hypophysis in vitro after electrical stimulation of the pituitary stalk

The isolated neurointermediate lobe of the rat hypophysis was incubated in Krebs solution and the stalk was electrically stimulated. The endogenous dopamine (DA) released into the medium was estimated by HPLC with electrochemical detection. Stimulation with biphasic pulses (1 ms, 10 Hz) in the presence of pargyline elicited a mean DA output of 200 fg X pulse-1. This release was calcium-dependent but was only partially inhibited by tetrodotoxin (TTX) (1 microM), effects typical for direct electrical depolarization of the nerve endings. Reducing the duration of the electric pulses to 0.2 ms (15 Hz) caused a reduction in DA output to about 40 fg X pulse-1 which was completely blocked by TTX indicating that it was evoked by propagated action potentials. DA overflow was enhanced when the action potential was prolonged with tetraethylammonium (TEA) or when DA uptake was inhibited with GBR 12921. Evidence for a calcium-dependent increase in DA synthesis in electrically stimulated NILs has been obtained when monoamine oxidase was inhibited and TEA or GBR 12921 was present in the Krebs solution. The present results complete the requirements for the DA in the NIL to be classified as a neurotransmitter substance. The NIL-pituitary stalk preparation is a useful model for studying regulatory mechanisms in dopaminergic nerve terminals.     

Acquisition and retrieval of information in amphetamine-treated hyperactive children

State-dependent learning and memory (retrieval) processes were examined in 15 amphetamine-treated hyperactive boys. While stimulant treatment enhanced the acquisition of information and its retrieval 24 hours later, there was no evidence of poorer retrieval of information learned in a state different from the retrieval state. Amphetamine appeared particularly to facilitate effortful cognitive processes. Subgroups of hyperactive children respond to amphetamine treatment in different ways, some showing changes in motor restlessness and others changes in cognition. The lack of dissociative effects when information is learned and recalled under different drug conditions suggests that what the stimulant-treated child learns can be effectively recovered after completion of treatment.     

Macroglossia: a case study

A young child with macroglossia of unknown cause was seen for treatment to modify resting tongue posture and improve speech sound production. Evaluation of the treatments indicated positive change in resting tongue posture and a modest change in speech sound production. Treatment for such patients can be complex and must consider orthodontic and/or surgical interventions, because an enlarged tongue can influence growth, development, and physiology of the oropharyngeal complex. The speech-language pathologist must be prepared to deal with the complex of problems demonstrated by patients with macroglossia during growth and development. LEARNING OUTCOMES: (1) As a result of this activity, the participant will be able to describe the sequelae of macroglossia. (2) As a result of this activity, the participant will be able to identify appropriate treatment options for children with macroglossia.