Biomedical subjects
Publications and source records attributed to S Boyd.
Unilateral cryptorchidism was induced in Wistar rat pups within 48 h of birth. After a period of 150 days, the blood-testis barrier was evaluated in the cryptorchid and contralateral scrotal testis, using a lanthanum immersion technique. The barrier was demonstrated to be competent, with tracer confined to the basal and intermediate compartments.
Two siblings with developmental delay and a non-progressive cerebellar ataxia are described. The electroencephalograms in both children showed a rather unusual pattern of high amplitude 10-12/s rhythms maximal anteriorly, while extensive neuronal migration abnormalities were apparent on Magnetic Resonance scans. There were no dysmorphic features, metabolic abnormalities, chromosomal defects or evidence of prenatal environmental toxins. It is considered that these siblings have an autosomal recessive neuronal migration defect which has not previously been reported.
From August 1982 through March 1988, 531 patients have undergone continent urinary diversion using an ileal reservoir constructed according to the method of Kock. For the last 18 months we have used the principle of Kock reservoir construction for primary lower urinary tract reconstruction after cystectomy in 39 highly selected male patients by means of a ureteroileal urethrostomy. Early complications occurred in 86 of 531 patients (16.2 per cent), resulting in an operative mortality rate of 1.9 per cent (10 of 531). The early complication rate was 16.5 per cent among patients undergoing 1-stage cystectomy and Kock pouch construction, and 15.2 per cent among patients undergoing Kock pouch conversion. Late complications have been analyzed in 489 patients who have undergone Kock cutaneous diversion. The complications unique to continent urinary diversion, their incidence and the effect of technical modifications in reducing the number of late complications are shown. Note that since the last modification in July 1985 the over-all incidence of late complication has decreased to 22 per cent. Based on this ongoing experience we conclude that the continent ileal reservoir, as conceived by Kock, remains the ideal internal reservoir for bladder replacement in terms of volume accommodation with the lowest internal pressures, and the intussuscepted ileal nipple valve mechanism is a reproducible, highly effective mechanism that prevents reflux and pyelonephritis in greater than 95 per cent of the patients and produces excellent continence. Our enthusiasm remains tempered by the need for reoperation in approximately 10 to 15 per cent of the patients, usually due to a pinhole fistula or false passage at the base of the efferent nipple valve mechanism. Electrolyte abnormalities rarely occur and in the absence of radiation gastrointestinal dysfunction is unusual. Continent urinary diversion is a viable concept that provides a real alternative in terms of quality of life and self-image for the patient who requires urinary diversion for any reason.
The purpose of these experiments was to define the temporal parameters involved in the phencyclidine (PCP) enhancement of 3H quinuclidinyl benzilate (QNB) accumulation in mouse brain. PCP enhanced QNB accumulation in brain if given intraperitoneally (IP) 1 and 4, but not 16 hours before intravenous (IV) administration of QNB. This effect was found in hypothalamus, striatum, cortex and hippocampus, but not cerebellum. PCP given after QNB did not alter QNB accumulation. The PCP enhancement persisted for at least 72 hours after QNB administration. These results confirm previous studies demonstrating that PCP must be present prior to QNB administration to enhance the accumulation and show that the effect persists for an extended period of time.
The arterial blood pressure, intracranial pressure, and organ system failure scores were reviewed for 49 infants and children with non-traumatic coma from various causes. The neurological outcome was good in 21 patients, moderate in five, and poor in 23. There was no significant difference in maximum intracranial pressures between patients with a good outcome and those with a poor one, but patients with a poor outcome had significantly lower minimum cerebral perfusion pressures. During the period of admission 18 patients had cardiovascular failure, none had renal failure, and two developed severe coagulopathy. Seventeen of the 19 patients in whom at least one of these systems failed died. Our findings emphasise the diversity of illnesses associated with raised intracranial pressure in children and the number who develop multiple organ failure, and the values and limitations of using minimum cerebral perfusion pressure and the organ system failure scores as guides to severity of illness and prognosis.
Forty eight comatose children had electroencephalograms (EEG) recorded during the acute phase of their illnesses. These were classified according to a simple grading system and the findings correlated with the presence of seizures, deep coma, minimum cerebral perfusion pressure, and eventual neurological outcome. Serial EEGs proved important, particularly when slow activity was seen initially. None of the 20 patients who showed low amplitude EEG activity or electrocerebral silence at any stage of the acute illness did well. Discharges were seen in only 13 of the 29 patients with seizures and their presence did not correlate with outcome except in five patients with a distinctive pattern of discharges, none of whom had a good outcome. EEG findings associated with poor outcome did not always correlate with the clinical assessment of deep coma, emphasising the difficulties of neurological evaluation in these patients. Five of the patients with cerebral perfusion pressures greater than 42 mm Hg had a poor outcome that was predicted by serial EEGs. In nine patients with a minimum cerebral perfusion pressure in the borderline range 38-42 mm Hg the EEG was useful as an indication of the outcome. The EEG reflects changes in cerebral function which may be due to multifactorial or repeated insults. An EEG is therefore important in both the initial assessment and as an indicator of the neurological outcome, particularly in those patients in whom the cerebral perfusion pressure has apparently been adequate or within the borderline range.
The clinical features of eight children with infantile neuroaxonal dystrophy are presented. Diagnosis was established by brain biopsy (4 cases), conjunctival biopsy (1 case), and the family history (2 cases), while in one case a presumptive diagnosis was made on the combination of clinical and neurophysiological findings without histopathological confirmation. The pleomorphic clinical picture and variable neurophysiological findings make a firm diagnosis difficult without histopathological confirmation. However, in the appropriate clinical context, serial neurophysiological investigations (ERG, VEP, EEG, ENMG) may suggest the diagnosis after the age of 2 years. Conjunctival biopsy is not invariably helpful, and neuroaxonal spheroïds are not always demonstrated in brain biopsies by conventional techniques. However, they were consistently identified using a non-specific esterase stain and by electron microscopy. This technique is described, and the significance of ultrastructural and neuropathological findings in infantile neuroaxonal dystrophy is discussed.
The rat striatum can be divided into patch and matrix compartments. Patches, as marked by high opiate receptor binding, first emerge perinatally from a dense, diffuse field of striatal opiate binding. Our quantitative analysis revealed that the patch compartment formed its peak proportion of the total striatal area at postnatal day 7. After this time, patches occupied a smaller proportion of the striatum, reflecting the fact that the number of patches and mean area per patch reached near adult levels during the first postnatal week, yet the volume of the striatum as a whole continued to increase for several weeks postnatally. Results from transplant and early postnatal lesion experiments suggested that connections between the striatum and other brain areas are important for the formation and/or maintenance of the patch and matrix compartments. Transplants of embryonic striatum to cavities in the cortex of young adult hosts developed diffuse opiate receptor binding but not dopamine receptor binding. Significantly, the opiate receptor binding seen in the transplants was never organized into the dense patches normally seen in the adult striatum. In a few transplants areas of relatively higher opiate receptor binding occurred in areas of relatively low neuronal cell density, as is seen in early normal development, but the dense adult patches never developed. Coronal diencephalic hemisections, but not decortications, in the early postnatal period produced drastic shrinkage of the striatum and, more importantly, a large decrease in opiate receptor patches when expressed as a proportion of total striatal area. Neuronal connections with more caudal brain structures may play a role in the final differentiation and maintenance of the striatal compartments.
Pancreatic function was assessed prospectively in a group of 18 treated adult coeliac patients, most of whom were asymptomatic. The para-aminobenzoic acid (PABA) test indicated exocrine pancreatic insufficiency in three patients, all of whom had persisting gastrointestinal symptoms. Arginine, 5 g intravenously, was used to stimulate pancreatic islet cells; basal and stimulated concentrations of plasma insulin, C-terminal glucagon, N-terminal glucagon, and blood glucose did not differ from asymptomatic nondiabetic control subjects. After gluten withdrawal, coeliac patients who responded clinically had no evidence of significant pancreatic impairment, but consideration of exocrine pancreatic insufficiency is worthwhile in those patients with persisting symptoms.
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Clinical features, complications and results of investigations are analysed in 50 patients diagnosed by jejunal biopsy as having coeliac disease at the Adult Gastroenterology Unit, Royal Victoria Hospital, Belfast, between 1969 and 1983. Only one patient was entirely asymptomatic, but 22% had no disturbance of bowel habit, and 50% had not lost weight. There were relatively few physical abnormalities on clinical examination. Screening tests using standard haematological and biochemical methods were positive only in between 8% and 52% of patients. More specific tests for malabsorption were positive in between 54% and 84% of patients. Jejunal biopsy remains the definitive procedure to identify patients with coeliac disease.
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This article presents an approach to total documentation of clinical laboratory methods that is practical and comprehensive. Primary reference documents including the bench method, all aspects of instrumentation, calibration, quality control, safety, results, and reporting conventions and back-up research data are entered into a matrix by section. This system has proved to be of great utility particularly in meeting regulatory demands and for the use and orientation of staff technologists.
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Explore the source record for details and available documents.