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M Preece

Publications and source records attributed to M Preece.

At least 19 recordsLinked to original sources
PubMed2006

Beyond counting cases: public health impacts of national Paediatric Surveillance Units.

Paediatric Surveillance Units (PSUs) have been established in 14 countries and facilitate national, prospective, active surveillance for a range of conditions, with monthly reporting by child health specialists. The International Network of Paediatric Surveillance Units (INoPSU) was established in 1998 and facilitates international collaboration among member PSUs and allows for sharing of resources, simultaneous data collection and hence comparison of data from different geographical regions. The impact of data collected by PSUs, both individually and collectively as members of INoPSU, on public health outcomes, clinical care and research is described.

Child↗
PubMed2003

Enterocystoplasty in childhood: a second look at the effect on growth.

OBJECTIVE: To re-evaluate the assumption that enterocystoplasty in children has a detrimental effect on linear growth (which is almost exclusively based upon a chance finding in a retrospective study 10 years ago) in a larger cohort and with a longer follow-up. PATIENTS AND METHODS: The original 12 children who had impaired linear growth in a previous study 10 years earlier were re-measured. A larger cohort was identified from the 242 children and adolescents who had undergone enterocystoplasty between 1982 and 1997. Patients with conditions involving organ systems apart from the urinary tract, and those with myelomeningocele, malignant diseases, reduced glomerular filtration rate and incomplete notes were excluded. In the definitive study cohort (123; mean age at operation 8.6 years; mean age at investigation 16.8 years) enterocystoplasty had been undertaken using colon in 70, ileum in 37, a combination of both in 11, ileocaecal segments in three and stomach in two patients. RESULTS: Of the original 12 patients, six had regained or surpassed their preoperative position on their growth charts. In all patients with a known target centile range the final height was within their genetic growth potential. In the cohort of 123 patients, 1215 height and weight measurements had been recorded. The distribution of percentile positions before and after enterocystoplasty showed a normal configuration, with 83% and 80% of patients growing within two standard deviations of the 50th percentile. After surgery, 85% either remained on the same or reached a higher centile. Nineteen (15.5%) were in a lower position, with a similar tendency in the weight centile. A clinically relevant growth disorder was recognized in four patients with a complete endocrinological evaluation; in none of these was enterocystoplasty thought to be a causal factor. CONCLUSIONS: It is very unlikely that the loss of the preoperative percentile position on the growth curve in 15% of children after enterocystoplasty is a consequence of the surgery. Rather it is a non-specific phenomenon that has to be considered in any clinical population of the same size and age distribution after the same length of time.

Adolescent↗
PubMed2003

[The effect of enterocystoplasty in childhood on linear growth].

OBJECTIVE: The assumption that enterocystoplasty in children has a detrimental effect on linear growth has been based almost exclusively upon a chance finding in a retrospective study 10 years ago. We re-evaluated the same research question in a larger cohort and with a longer follow-up. PATIENTS AND METHODS: Between 1982 and 1997, 242 children and adolescents underwent enterocystoplasty. Patients with conditions involving organ systems apart from the urinary tract, and those with myelomeningocele, malignant diseases, reduced glomerular filtration rate and incomplete notes were excluded. In the definitive study cohort (123; mean age at operation 8.6 years; mean age at investigation 16.8 years), enterocystoplasty had been undertaken using colon in 70, ileum in 37, a combination of both in 11, ileocaecal segments in three and stomach in two patients. RESULTS: In all, 1215 height and weight measurements had been recorded. The distribution of percentile positions before and after enterocystoplasty showed a normal configuration, with 83 % and 80 % of patients growing within two standard deviations of the 50th percentile. After surgery, 85 % either remained the same or reached a higher percentile. Nineteen (15.5 %) were in a lower position, with a similar tendency in the weight percentile. A clinically relevant growth disorder was recognized in four patients with a complete endocrinological evaluation; in none of these was enterocystoplasty thought to be a causal factor. CONCLUSIONS: It is very unlikely that loss of the preoperative percentile position on the growth curve in 15 % of children after enterocystoplasty is a consequence of that particular surgery. Rather, it is a non-specific phenomenon that has to be considered in any clinical population of the same size and age distribution after the same length of time.

Adolescent↗
PubMed2001

Detection of pharmacologically mediated changes in cerebral activity by functional magnetic resonance imaging: the effects of sulpiride in the brain of the anaesthetised rat.

Blood oxygenation level dependent (BOLD) contrast functional magnetic resonance imaging (fMRI) was used to study the effects of the D(2)-like receptor selective antagonist, sulpiride, at 2 Tesla in the brain of the alpha-chloralose anaesthetised rat. Region of interest (ROI) analysis indicated significant (P<0.05) bilateral increases in BOLD signal intensity in the frontal cortex following a single administration of sulpiride (10 mg/kg i.v.). BOLD signal changes were slow in onset and increased gradually during the experiment, reaching 8.0+/-0.5% (mean+/-S.E.M.) above pre-injection control values 165 min after drug administration. Signal increases remained high at the experiment end (3 h post sulpiride administration). Sulpiride (30 mg/kg i.v.) had a similar effect in the frontal cortex, increasing signal 5.2+/-1.8% above control values by 174 min; its effects were, however, more variable between rats, and were not statistically significant. Sulpiride (3 mg/kg i.v.) had no significant effect upon BOLD signal intensity in any brain region. No dose of sulpiride resulted in any significant BOLD signal changes in the striatum or cerebellum. These data are supportive of the notion that sulpiride causes an increase in frontal dopaminergic function by antagonism of presynaptically located dopamine D(2) receptors in this brain region, consistent with its therapeutic action. Furthermore, the utility of BOLD contrast fMRI as a means of detecting changes in neuronal activity contingent upon the administration of a psychoactive pharmacological agent has been demonstrated.

Animals↗
PubMed2001

Post-tonsillectomy bleed: a delayed diagnosis of duodenal ulceration.

Post-operative haemorrhage is one of the commonest complications of tonsillectomy. We report a case of a 36-year-old lady who presented with three haemorrhagic episodes following tonsillectomy. Although initially treated as secondary tonsillar haemorrhage, the actual cause of the bleeding was later identified to be a duodenal ulcer. The case is presented with a review of the literature.

Adult↗
PubMed2000

Iatrogenic Creutzfeldt-Jakob disease at the millennium.

The causes and geographic distribution of 267 cases of iatrogenic Creutzfeldt-Jakob disease (CJD) are here updated at the millennium. Small numbers of still-occurring cases result from disease onsets after longer and longer incubation periods following infection by cadaveric human growth hormone or dura mater grafts manufactured and distributed before the mid-1980s. The proportion of recipients acquiring CJD from growth hormone varies from 0.3 to 4.4% in different countries, and acquisition from dura mater varies between 0.02 and 0.05% in Japan (where most cases occurred). Incubation periods can extend up to 30 years, and cerebellar onsets predominate in both hormone and graft recipients (in whom the site of graft placement had no effect on the clinical presentation). Homozygosity at codon 129 of the PRNP gene is over-represented in both forms of disease; it has no effect on the incubation period of graft recipients, but may promote shorter incubation periods in hormone cases. Knowledge about potential high-risk sources of contamination gained during the last quarter century, and the implementation of methods to circumvent them, should minimize the potential for iatrogenic contributions to the current spectrum of CJD.

Creutzfeldt-Jakob Syndrome↗
PubMed2000

Herpes zoster oticus following mandibular block.

Although a few cases of facial palsy following mandibular nerve block and dental surgery have been described, it would appear that herpes zoster oticus following dental surgery has not been documented. It is possible that the latent virus may be activated by the mandibular nerve block and dental surgical interventions. Two cases of herpes zoster oticus, both following inferior alveolar nerve block anaesthesia for dental treatment are presented.

Adult↗
PubMed2000

Bone mineral content and bone mineral metabolism: changes after growth hormone treatment in juvenile chronic arthritis.

OBJECTIVE: To determine whether growth hormone (rhGH) affects bone mineral metabolism and bone mineral content (BMC, g/cm) in a therapeutic trial of recombinant growth hormone in growth retarded children with juvenile chronic arthritis (JCA) treated with steroid. METHODS: BMC was measured in 20 children (of whom 17 were treated with corticosteroid) before and after one year of rhGH. Children were randomized to receive either low dose (12 IU/m2/week) or high dose (24 IU/m2/week) for one year. Three monthly assessments were made of disease activity and anthropomorphic measurements. Blood and urine samples were also obtained to measure indicators of disease activity, bone remodeling, and vitamin D and parathyroid hormone (PTH) status. RESULTS: BMC increased during the treatment period and correlated with increasing height. Osteocalcin levels, normally indicators of bone formation, increased after rhGH treatment and correlated significantly with height velocity, particularly for the high dose treatment group. In contrast, osteocalcin levels were negatively correlated with C-reactive protein levels, both before and during treatment. Height velocity, vitamin D, PTH, and osteocalcin levels were significantly lower than age matched controls before treatment. CONCLUSION: Steroid treated children with both JCA and severe growth retardation have reduced vitamin D, PTH, and osteocalcin levels. After treatment with rhGH, height velocity increased, as did BMC. Growth hormone might be a useful adjunct in the treatment of severe growth retardation and osteoporosis in children with JCA. The longterm benefits of rhGH in the treatment of osteoporosis remain unclear.

Adolescent↗
PubMed1999

The search for the gene for Silver-Russell syndrome.

Patients with Silver-Russell syndrome display intrauterine growth restriction and other dysmorphic features. No single genetic cause for this syndrome has been found, although there are a small number of familial cases and some patients with chromosomal rearrangements. Maternal uniparental disomy of chromosome 7 has been found in approximately 7% of patients with Silver-Russell syndrome. In five of these patients exhibiting maternal uniparental disomy, no common regions of isodisomy were found, thereby ruling out the expression of a recessive allele. It is most likely that one or more imprinted genes are responsible for the phenotype of Silver-Russell syndrome. Human chromosome 7 demonstrates homology with two imprinted regions on mouse chromosomes 6 and 11, which are equivalent to human chromosome regions 7q32 and 7p11-p13, respectively. We directly analysed the imprinting status of candidate genes from chromosome 7 that mapped to homologous imprinted regions in the mouse and also had a potential role in growth. The candidates were the genes that encode the epidermal growth factor receptor and the insulin-like growth factor binding proteins-1 and -3. All three of these candidate genes are localized to chromosome region 7p11-p13. Using intragenic polymorphisms as markers, we found that all three genes showed biallelic expression in different fetal tissues. Therefore, it is unlikely that these candidate genes are directly involved in producing the phenotype of Silver-Russell syndrome. Other candidates are under analysis, including two newly identified genes that are known to be imprinted.

Abnormalities, Multiple↗
PubMed1999

Ultrastructural evaluation of lung maturation in a sheep model of diaphragmatic hernia and tracheal occlusion.

In fetuses with diaphragmatic hernia (DH) lung development is impaired, and pulmonary hypoplasia is one of the main factors responsible for the poor outcome of the disease. A possible treatment consists of occluding trachea during lung development to retain pulmonary fluid and to force the lung to expand. Although it appeared promising at first, this technique has recently been reported to decrease type II cell number and to induce surfactant deficiency. The aim of this study was to investigate lung maturation further through ultrastructural examination in a fetal lamb model of DH created at 85 d, followed or not by endoscopic balloon tracheal occlusion (TO) at 120 d of gestation. The proportion of alveolar epithelial type I and type II cells was altered by both treatments: the type I/type II cell ratio, which was about 2 in control lungs, was decreased 4.5-fold in DH lungs but was increased 4.5-fold in DH+TO lungs. The proportion of undifferentiated cells was increased in DH lungs. Indeterminate cells sharing features of type II and type I cells that were not observed in controls were seldom seen in DH lungs and were numerous in DH+TO lungs. The number of lamellar bodies per type II cell was decreased in both DH and DH+TO groups. In DH lungs, wall structure presented an immature appearance, with cellular connective tissue and poor secondary septation of saccules. In DH+TO lungs, primary septa appeared more mature, with reduced connective tissue, but secondary septa were still buds, although elastin was present at their tips. A single capillary layer was found in all three groups (control, DH, and DH+TO) with no sign of septal capillary pairing. This first investigation in DH and DH+TO lungs through transmission electron microscopy thus enabled us to show that compression and forced expansion of the lung are both responsible for alterations in type II cell differentiation and septal development.

Airway Obstruction↗
PubMed1997

Fetal and maternal plasma insulin-like growth factors and binding proteins in pregnancies with appropriate or retarded fetal growth.

A prospective observational study of 104 women was performed to study whether the insulin-like growth factor (IGF) system in pregnancy before labour is associated with reduced fetal growth. Fetal blood was obtained by cordocentesis for prenatal diagnosis or at elective caesarean delivery and a maternal sample was also obtained, IGF-1 and IGF-2 and their binding proteins -1 and -3 were measured by RIA. The 35 case were smaller than -2S.D.s by ultrasound abdominal circumference and birthweight and were subdivided into fetal growth retardation (FGR, n = 20) and small for gestational age (SGA, n = 15) by Doppler velocimetry and neonatal outcome. Controls (n = 69) were normally grown. Control maternal IGF-1 (r = 0.65, P < 0.0001) and IGFBP-3 (r = 0.46, P = 0.001) increased with advancing gestational age. In FGR cases, maternal IGF-1 was low (P = 0.0001) and IGFBP-1 was high (P = 0.03) and maternal IGF-2 was low in SGA (P = 0.005). In the SGA fetus, IGF-2 was low (P = 0.0009) and IGFBP-3 (P = 0.02) was high. In FGR, IGFBP-1 (P < 0.0001) and IGFBP-3 (P = 0.002) were both elevated. These data do not support the hypothesis that fetal IGF-1 deficiency is a common cause of FGR. Elevated binding proteins may lead to a relative deficiency of free IGF but changes in binding proteins may be secondary to metabolic changes. In FGR, maternal IGF-1 was low with high binding proteins, so this system may be important in controlling placental transfer.

Embryonic and Fetal Development↗
PubMed1994

Age at menarche.

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Adolescent↗
PubMed1994

Assessment of Physical Growth and Pubertal Development.

Growth is far too complex to be described only in terms of height and weight in relation to age. In addition to addressing multiple factors that have clinical value in the assessment of growth in adolescence, this chapter discusses the interpretation of growth data, growth at puberty, and methods of predicting height at maturity.

Journal Article↗