PubMed Health⌕ Search

Biomedical subjects

N J Shaw

Publications and source records attributed to N J Shaw.

At least 91 records · Page 5Linked to original sources
PubMed1997

Bone mineral density in Turner's syndrome--a longitudinal study.

OBJECTIVE: Osteoporosis is a recognized problem in adult women with Turner's syndrome, the aetiology of which is unclear. The aim of this study was to examine bone mineralization longitudinally in a group of girls with Turner's syndrome and to study the effect of different treatments on bone mineral density. DESIGN: A prospective observational study. PATIENTS: Eighteen girls with Turner's syndrome aged 4-17 years attending a paediatric endocrine clinic. MEASUREMENTS: Bone mineral density of the lumbar spine was assessed using dual energy X-ray absorptiometry at several time points over a 2.5-year period. RESULTS: Only one girl had evidence of a significant reduction in bone density when comparisons were made with control data related to body weight and pubertal status. No advantage was found for any form of treatment in optimizing bone mineralization. CONCLUSIONS: As there is little evidence of reduced bone mineral density in girls with Turner's syndrome there is no justification for an early introduction of oestrogen replacement during the prepubertal years.

Adolescent↗
PubMed1997

Growth of Pakistani children in relation to the 1990 growth standards.

This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background.

Adolescent↗
PubMed1997

Blood culture volume and detection of coagulase negative staphylococcal septicaemia in neonates.

A prospective, blind study was carried out to determine: the amount of blood submitted for culture from neonates; whether small blood volumes resulted in false negative results; and whether there was a temporal relation between volume of blood cultured and time to positivity. Seventy three bottles were evaluated. They contained a median of 0.63 ml of blood. Twenty nine bottles (39.7%) contained less than 0.5 ml of blood; 21 bottles (28.8%) were positive. There were three false negative cultures, only one of which contained a blood volume below 0.5 ml. The median time to positivity was 22.4 hours. There was no correlation between blood volume cultured and time to positivity. Neonatal cultures frequently contain less than 0.5 ml of blood. False negative cultures are rare. Neonatal blood culture bottles need to be validated for blood volumes below 0.5 ml.

Bacteremia↗
PubMed1997

Renal calcification in preterm infants: follow up at 4-5 years.

AIM: To determine the consequences of renal calcification in preterm infants. METHODS: A cohort of 11 preterm babies was studied at the age of 4 to 5 years. They had had renal calcification as neonates. Seventeen matched controls were also studied. Each child had a renal ultrasound scan, a calcium load test, and a desmopressin test for renal concentrating ability (RCA). The study group also had glomerular filtration rate (GFR) estimated, using the height:creatinine ratio, and tubular phosphate reabsorption, without phosphate load, per glomerular filtration rate (Tp/GFR) calculated, RESULTS: In the study group the median GFR was 61 ml/min/1.73m2 (range 46-79 ml/min/1.73m2) and the median calculated Tp/GFR SD score was -0.94 (range -2.8-0.68). Five children out of the study group had ultrasonic evidence of renal calcification. There was no significant difference between the two groups in renal size, calciuria, before or after calcium load, or RCA. Eight children (three patients, five controls) had an abnormal calcium load test. The RCA of the children in the study and control groups combined was below that of published values, with a median calculated SD score -0.71 (95% CI -1.21 to -0.23). CONCLUSIONS: There was evidence of renal dysfunction in children who had been born preterm. Renal calcification detected in the neonatal period does not seem to be a major predisposing factor for the abnormalities of renal function subsequently observed in these infants.

Calcinosis↗
PubMed1997

Open randomised controlled trial of inhaled nitric oxide and early dexamethasone in high risk preterm infants.

AIM: To determine whether treatment with inhaled nitric oxide (NO) and/or dexamethasone reduces the incidence of chronic lung disease (CLD) and/or death in high risk preterm infants. METHODS: Infants below 32 weeks of gestation were recruited at 96 hours of age if they were deemed to be at high risk of developing CLD. Infants were randomly assigned to one of four treatment groups using a factorial design: (1) 5-20 parts per million inhaled NO for 72 hours; (2) 0.5-1 mg/kg/day intravenous dexamethasone for 6 days; (3) both drugs together; (4) continued conventional management. RESULTS: Forty two infants were randomised: 10 infants received inhaled NO alone; 11 dexamethasone alone; 10 both treatments; and 11 neither treatment. There was no difference in the combined incidence of CLD and/or death before discharge from hospital between either infants treated with inhaled NO and controls (RR 1.05, 95% CI 0.84-1.25), or those treated with dexamethasone and controls (RR 0.95, 95% CI 0.79-1.18). CONCLUSIONS: At 96 hours of age, neither treatment with inhaled NO nor dexamethasone prevented CLD or death.

Administration, Inhalation↗
PubMed1997

Changes in oxygenation and pulmonary haemodynamics in preterm infants treated with inhaled nitric oxide.

AIM: To investigate changes in various cardiorespiratory variables with inhaled nitric oxide (NO), as part of a randomised controlled trial. METHODS: Infants were treated with inhaled NO for 72 hours. Changes in oxygenation were assessed using the oxygenation index (OI). Serial changes in pulmonary artery pressure (PAP) were assessed using the Doppler derived acceleration time to right ventricular ejection time ratio (AT:RVET). Doppler measurements of right ventricular output, pulmonary blood flow, and systolic PAP was performed in a subset of infants. RESULTS: Twenty infants received inhaled NO and 22 acted as controls. Infants were treated at a median dose of 5 (range 5 to 20) ppm. There was a fall in median OI by 17% in treated infants within 30 minutes of treatment. The fall in OI in treated infants was significantly different from the response in controls until 96 hours. Infants treated with inhaled NO showed a rapid response with a median rise in AT:RVET of 0.04 (range -0.06 to 0.12) within 30 minutes. The change in AT:RVET was significantly different from controls until 4 hours. Median systolic PAP also fell in treated infants by 6.1 (range -14.4 to -4.4) mm Hg within 1 hour. Changes in OI were significantly associated with changes in PBF (r = 0.44), but not with changes in AT:RVET. CONCLUSION: Treatment with inhaled NO rapidly improves oxygenation and lowers PAP in preterm infants. However, these effects are transient and treatment does not influence long term outcome.

Administration, Inhalation↗
PubMed1996

Intraobserver variation in Doppler ultrasound assessment of pulmonary artery pressure.

Intraobserver variation associated with the non-invasive assessment of pulmonary artery pressure (PAP), using measurement of pulmonary artery Doppler derived systolic time intervals, was investigated. Forty pairs of independent ultrasound examinations of the pulmonary artery were performed by a single observer in 20 preterm infants, median gestation 27 weeks (range 24-31 weeks). Median age at study was 17 days (range 1-47 days). paired measurements of acceleration time (AT), ratio between acceleration time and right ventricular ejection time (AT:RVET), corrected AT, and corrected AT:RVET were compared to assess intraobserver agreement. For the corrected AT:RVET ratio, the mean percentage difference between observations was -0.9% (95% confidence intervals -5.0 to 3.1%). The limits of agreement for the two measurements were -26.3 to 24.5%. The coefficient of repeatability was 25.4%. Variation for other indices was similar. Non-invasive assessment of PAP using Doppler derived systolic time intervals is associated with considerable intraobserver variation.

Blood Pressure Determination↗
PubMed1995

Microbial characteristics and severity of coagulase-negative staphylococcal septicaemia in premature neonates.

A pilot study was undertaken to assess the predictive value of characteristics possessed by coagulase-negative staphylococci in determining clinically important infection in premature neonates. No significant association was demonstrated between organism properties and clinical indices of infection. The routine use of simple measures of microbial characteristics in the assessment of neonatal septicaemia is not warranted.

Anti-Bacterial Agents↗
PubMed1995

The use of pulse oximetry in the prevention of hyperoxaemia in preterm infants.

UNLABELLED: When deciding an appropriate upper limit for pulse oxygen saturation (SpO2) in preterm infants the usefulness of current data is limited by the fact that previous studies have examined a population of more mature infants and children or have applied various exclusion criteria which produce results unrepresentative of clinical practice. We tested the hypothesis of previous workers that maintaining the SpO2 below 98% would ensure an arterial oxygen tension (PaO2) less than 12kPa. A total of 477 simultaneous measurements of PaO2 and SpO2 were made using Ohmeda Biox oximeters on 43 infants who were less than 33 weeks gestation and receiving supplementary oxygen. Of 435 measurements performed when the SpO2 was 97% or less, 26 (6%) had a PaO2 greater than 12kPa. Further examination of the data showed that of 108 estimations performed when the SpO2 was less than 94%, none had a PaO2 greater than 12kPa. CONCLUSION: When using Ohmeda Biox pulse oximeters an upper limit of 97% for SaO2 is not effective in preventing hyperoxaemia; however, a limit of 93% is likely to maintain the PaO2 below 12kPa.

Acidosis↗
PubMed1995

Urinary pyridinoline and deoxypyridinoline excretion in children.

OBJECTIVE: There are few data on urinary markers of collagen breakdown in children. We have determined a normal range for urinary pyridinoline and deoxypyridinoline in children, assessed the variability in excretion in individual children and examined the effect of GH treatment on the excretion of these collagen cross-links. DESIGN: A cross-sectional study of a group of healthy children and sequential samples from children receiving GH treatment. PATIENTS: One hundred and nine healthy children aged 2-15 years, 8 healthy children aged 4-11 years and 4 children receiving GH treatment. MEASUREMENTS: Total pyridinoline and deoxypyridinoline excretion were measured by high performance liquid chromatography after initial acid hydrolysis and cellulose extraction steps. Serum parathyroid hormone was measured using a two-site immunoradiometric assay and urinary hydroxyproline by Ehrlich's reaction using a colorimetric assay. Pyridinoline and deoxypyridinoline excretion were expressed as a ratio against urine creatinine. RESULTS: High excretion of pyridinoline (Pyr) and deoxypyridinoline (DPyr) was seen at all ages with no apparent relation to age (mean Pyr/Cr 115 nmol/mmol and DPyr/Cr 31 nmol/mmol). No correlation was found with serum parathyroid hormone or urinary hydroxyproline excretion. Marked day to day variation was seen in individual children. A progressive rise in excretion was seen in children receiving GH treatment with no significant correlation to height velocity. CONCLUSIONS: There is a high excretion of the pyridinium cross-linking amino acids in children of all ages compared to adults. However, a high variability exists in single morning urine samples which will limit the usefulness of these markers in growing children.

Adolescent↗