PubMed Health⌕ Search

Biomedical subjects

R McWilliam

Publications and source records attributed to R McWilliam.

At least 19 recordsLinked to original sources
PubMed2006

Investigation of global developmental delay.

The investigation of global developmental delay in preschool children varies between centres and between paediatricians. Following a literature search and review of the evidence base, guidelines were developed to assist in the assessment and management of such children presenting to secondary level services. Evidence supporting the use of genetic and biochemical investigations on a screening basis was found, but there was no evidence to support the use of metabolic investigations or neuroimaging in the absence of other positive findings on history or examination. Detailed history and examination are paramount in the assessment of children with global developmental delay. Investigations can be a useful adjunct in determining aetiology. Evidence based guidelines have been developed to assist doctors in the selection of appropriate investigations for this group of children.

Child, Preschool↗
PubMed2005

Nonplanar photolithography with computer-generated holograms.

We outline a method for accomplishing photolithography on grossly nonplanar substrates. First we compute an approximation of the diffraction pattern that will produce the desired light-intensity distribution on the substrate to be patterned. This pattern is then digitized and converted into a format suitable for manufacture by a direct-write method. The resultant computer-generated hologram mask is then used in a custom alignment tool to expose the photoresist-coated substrate. The technique has many potential applications in the packaging of microelectronics and microelectromechanical systems.

Journal Article↗
PubMed2001

Non-progressive mental retardation and peripheral neuropathy in a mother and her son.

The association of facial dysmorphism, moderate mental retardation and peripheral neuropathy was observed in a mother and her son. The son also has pyramidal tract involvement in the lower limbs. Although exactly the same association has not been described previously, it seems probable that it results from variable expression of a dominant gene defect.

Adolescent↗
PubMed2000

Aicardi-Goutières syndrome displays genetic heterogeneity with one locus (AGS1) on chromosome 3p21.

We have studied 23 children from 13 families with a clinical diagnosis of Aicardi-Goutières syndrome. Affected individuals had developed an early-onset progressive encephalopathy that was characterized by a normal head circumference at birth, basal ganglia calcification, negative viral studies, and abnormalities of cerebrospinal fluid comprising either raised white cell counts and/or raised levels of interferon-alpha. By means of genomewide linkage analysis, a maximum-heterogeneity LOD score of 5.28 was reached at marker D3S3563, with alpha=.48, where alpha is the proportion of families showing linkage. Our data suggest the existence of locus heterogeneity in Aicardi-Goutières syndrome and highlight potential difficulties in the differentiation of this condition from pseudo-TORCH (toxoplasmosis, rubella, cytomegalovirus, and herpes simplex virus types 1 and 2) syndrome.

Abnormalities, Multiple↗
PubMed2000

Reduced accommodative function in dyskinetic cerebral palsy: a novel management strategy.

A 9-year-old boy with dyskinetic cerebral palsy secondary to neonatal encephalopathy is described. He presented with blurring of near vision which had begun to impact on his school work. Objective assessment of accommodation showed that very little was present, although convergence was almost normal. The near-vision symptoms were completely removed and reading dramatically improved with the provision of varifocal spectacles. Varifocal lenses provide an optimal correction for far, intermediate (i.e. for computer screens), and near distances (i.e. for reading). Managing this type of patient with varifocal spectacles has not been previously reported. It is clearly very important to prescribe an optimal spectacle correction to provide clear vision to optimize learning.

Accommodation, Ocular↗
PubMed1999

Factor V Leiden, prothrombin 20210G-->A and the MTHFR C677T mutations in childhood stroke.

Ischaemic stroke is a rare occurrence in children and in a proportion of cases the aetiology remains unknown. We have investigated the role of thrombophilia in the aetiology of this condition. Of 50 cases identified at two centres, 37 were available for detailed haematological analysis. No cases were identified with deficiencies of antithrombin, protein C or protein S. One case had elevated IgG anticardiolipin antibodies at low titre. The prevalence of the prothrombin 20210 G-->A mutation, factor V Leiden (FVL) mutation and the C677T mutation in the MTHFR gene was compared in cases to that observed in random unselected cord blood controls. The odds ratio for stroke was not significantly increased in carriers of the prothrombin mutation (OR 1.2; 95% CI 0.1-10.7), FVL (OR 2.5; 95% CI 0.5-13.5), or the C677T mutation (OR 1.7; 95% CI 0.6-4.5). Our findings suggest that thrombophilia may not play a significant role in the aetiology of stroke in children, although a large prospective study is required to investigate this area further.

Age Factors↗
PubMed1998

"Cataplexy" and muscle ultrasound abnormalities in Coffin-Lowry syndrome.

The Coffin-Lowry syndrome is a rare cause of mental retardation recognised by its distinctive facial and digital features. We have observed an unusual, non-epileptic, cataplexy-like phenomenon in three subjects with the syndrome and we speculate that this feature may go unrecognised. We also provide evidence of neuromuscular dysfunction as part of the phenotype by showing abnormalities on muscle ultrasound in four gene carriers.

Cataplexy↗
PubMed1989

The optimum dietary amino acid pattern for growing pigs. 2. Requirements for maintenance and for tissue protein accretion.

Experiments were made to estimate separately the amino acid requirements of growing pigs for maintenance and for protein accretion. The relationship between nitrogen retention and amino acid intake was estimated for each essential amino acid (except histidine) by giving, at rates of N intake of 0.25 and 2.0 g/kg body-weight (W)0.75 per d, diets in which one amino acid was made specifically deficient. From the regression coefficients it was calculated that, for the accretion of 1 g body protein, the dietary amino acid requirements were (mg) threonine 47, valine 53, methionine + cystine 36, methionine 19, isoleucine 43, leucine 78, phenylalanine + tyrosine 84, phenylalanine 41, lysine 68 and tryptophan 12. The daily amino acid requirements for N equilibrium were also estimated. From the relationship between N retention and amino acid intake the daily amino acid requirements for N equilibrium were estimated to be (mg/kg W0.75 per d) threonine 53, valine 20, methionine + cystine 49, methionine 9, isoleucine 16, leucine 23, phenylalanine + tyrosine 37, phenylalanine 18, lysine 36 and tryptophan 11. It was estimated that both for maintenance and for protein accretion tyrosine could provide close to half the total phenylalanine + tyrosine needs. Cystine could supply close to half the total sulphur amino acid needs for protein accretion but 0.8 of the needs for maintenance.

Amino Acids↗
PubMed1988

Palmoplantar keratoderma, nail dystrophy, and hereditary motor and sensory neuropathy: an autosomal dominant trait.

Autosomal dominant inheritance of a syndrome comprising palmoplantar keratoderma, nail dystrophy, and hereditary motor and sensory neuropathy (HMSN) was observed in three generations of one family. Nail dystrophy affected the toe and fingernails; it was present at birth or developed during early childhood. Palmoplantar keratoderma became apparent in later childhood. Each subject with nail dystrophy and keratoderma also had clinical or electrophysiological evidence of axonal neuropathy.

Child↗
PubMed1986

Somatosensory evoked potentials in the detection of spinal cord ischemia in aortic coarctation repair.

Cortical somatosensory evoked potential (SEP) monitoring was used in 15 patients 2 to 50 years old undergoing repair of aortic coarctation to detect the onset of spinal cord ischemia during the cross-clamp period. Three different response patterns were observed. In 8 patients (53%), the SEP remained unchanged throughout the cross-clamping. This was designated a type 1 response. Six patients (40%) showed a gradual deterioration in the SEP after 15 minutes of cross-clamping (type 2 response). All SEPs returned to normal levels within 5 minutes of release of the clamp. One patient (7%) demonstrated a decline in SEP commencing prior to the application of the cross-clamp when an intercostal vessel was controlled with slings. The SEP completely disappeared within 5 minutes of cross-clamping, but after 19 minutes the repair was completed and the SEP returned within 3 minutes of reperfusion (type 3 response). No patient sustained neurological sequelae of repair. We believe that SEP monitoring offers the potential to identify the patient at risk of developing spinal cord ischemia intraoperatively before irreversible damage occurs. However, it is susceptible to deep halothane anesthesia, which abolishes all cortical responses and requires expert monitoring.

Adolescent↗
PubMed1982

Dry-bed training in the treatment of nocturnal enuresis in childhood: a research report.

After one subject withdrew from an original group of twelve, eleven children with severe nocturnal enuresis were successfully treated by the Dry-Bed method. The children were aged five to nine years. The group median for the duration of treatment was four weeks, dryness being defined as two successive weeks without a bed-wetting incident. Training periods ranged from two to twenty weeks. Subsequently, two subjects relapsed, although organic and psychiatric factors respectively were probably responsible. At nine-month follow-up 73% of subjects were completely dry. The procedure made heavy demands on parents and clinician; especially in its initial phase. It was suggested that further feasibility studies are required of te Dry-Bed method of treatment in everyday service contexts.

Behavior Therapy↗
PubMed1979

Monitoring response to bronchodilator therapy in asthma in childhood.

Recently there has been increased interest in the role of bronchodilators in the maintenance therapy of asthma in childhood. We report the use of slow-release aminophylline (Phyllocontin Continus tablets) in childhood asthma. Ten patients, all of whom were receiving disodium cromoglycate (DSG), were given a single dose of Phyllocontin tablets (12.5 mg/kg) and observed over a period of 8 hours. Measurements of peak flow rate (PFR) and forced expiratory volume in one second (FEV1) showed an increase of at least 30% at 3 to 5 hours and the improvement continued to 8 hours. No effect was noted on heart rate. Ten patients were assessed over a 4-week period on DSG then over two 4-week periods on Phyllocontin tablets and placebo on a double-blind crossover basis. The dosage of Phyllocontin tablets used was 12.5 mg/kg twice daily. Using twice daily PFR recordings there was no significant difference between the two periods on DSG and Phyllocontin tablets. The reduction in PFR during the period on placebo was significant, however, and more markedly so between the period of placebo and the period on Phyllocontin tablets. We conclude that Phyllocontin tablets in these patients compared favourably with DSG in the maintenance therapy of asthma in childhood. The results obtained after single dose administration also suggest that a proportion of children with asthma may benefit from combined treatment with DSG and regular bronchodilators.

Aminophylline↗