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P Sharpe

Publications and source records attributed to P Sharpe.

At least 19 recordsLinked to original sources
PubMed2006

A systematic review of guidelines for the prevention of heat illness in community-based sports participants and officials.

This paper presents the findings of a systematic review of guidelines on preventing heat illness in sports participants and officials. University library databases and Internet sources were searched for guidelines pertaining to community-based sports, and occupational health and safety, using a comprehensive list of search terms. Guidelines were included if they met the criteria of English language, full text and fully referenced, and dealt specifically with, or could be extrapolated to, prevention of heat illness in sports participants and officials. Guideline inclusion was evaluated by two independent reviewers, who also independently assessed guideline quality using the AGREE instrument. Common guideline themes were identified by synthesis and recommendations for each theme were extracted. A synthesis of recommendations for common themes was then undertaken. Thirteen eligible guidelines were included. Thirty-two guidelines were excluded, as they did not provide sufficient information on construction or references. The methodological quality of the included guidelines was variable. The evidence-base of the guidelines varied, reflecting primary and secondary research. While five common heat-illness prevention themes were identified (fluid intake, heat limits, clothing, acclimatisation, precautionary interventions), variable recommendations were made pertaining to these themes. This potentially reflected the variable underpinning evidence of the guidelines. This review highlighted the need for better quality guideline construction related to defensible and transparent evidence sources regarding sports participation in hot weather. The synthesised recommendations cautiously provide a framework of current best evidence upon which sporting organisations internationally can base strategies for safe participation in the heat.

Adaptation, Physiological↗
PubMed2006

Prevalence of hot weather conditions related to sports participation guidelines: a South Australian investigation.

BACKGROUND: There is scant guidance in the literature on the most appropriate Australian measures of, and thresholds for, extreme heat regarding giving advice on safe sports participation in hot weather. The purpose of this paper is to present a process for investigating two common measures of heat (air temperature, wet bulb globe temperature (WGBT)) in one state in Australia (South Australia), regarding their usefulness in making decisions regarding sports participation in the heat. METHOD: Commonly reported measures and thresholds of extreme heat were identified from a systematic review of guidelines regarding sports participation in hot weather. Dry air temperature (threshold of 35 degrees C), and WBGT index (threshold of 28 degrees C) were highlighted. Repeated daily measures of dry air temperature by the Bureau of Meteorology (BoM) and WBGT index from 12 meteorological recording sites in South Australia (SA) for four consecutive summer periods (2000-2004) were analysed using these thresholds to investigate the prevalence of extremely hot temperatures in SA during these periods. The extremely hot hours-per-day data were standardised using a denominator of per-day-month across the 12 SA recording regions. RESULTS: Across the four summer seasons of data in SA, there were similar standardised numbers of hours-per-day of extremely hot dry air temperature and WBGT index. There was a high correlation between these hours of hot weather measures, highlighting the congruence between hot air and humidity measures. Three distinct regional site groupings were identified, in which there was a different prevalence of extremely hot weather conditions. CONCLUSION: In SA, dry air temperature is an appropriate and robust measure of extreme heat related to sports participation, this measure providing as much information as WBGT in identifying extremely hot periods of weather. Dry air temperature can be readily measured by sports participants or officials irrespective of the geographical location in SA. Three SA regions demonstrated distinct differences in prevalence of extremely hot conditions, suggesting the need for site-specific interpretation of heat participation guidelines to ensure sports safety in hot weather. Other states in Australia could use the approach outlined in this paper to identify the most appropriate measure of extreme heat relevant to local conditions, and to assist in interpreting heat limit guidelines in a local context.

Hot Temperature↗
PubMed2005

Differences in risk factors between early and late diagnosed developmental dysplasia of the hip.

BACKGROUND: Developmental dysplasia of the hip (DDH) is common, affecting 7.3 per 1000 births in South Australia. Clinical screening programmes exist to identify the condition early to gain the maximum benefit from early treatment. Although these screening programmes are effective, there are still cases that are missed. Previous research has highlighted key risk factors in the development of DDH. OBJECTIVE: To compare the risk factors of cases of DDH identified late with those that were diagnosed early. METHODS: A total of 1281 children with DDH born in 1988-1996 were identified from the South Australian Birth Defects Register. Hospital records of those who had surgery for DDH within 5 years of life were examined for diagnosis details. Twenty seven (2.1%) had been diagnosed at or after 3 months of age and were considered the late DDH cases (a prevalence of 0.15 per 1000 live births). Various factors were compared with early diagnosed DDH cases. RESULTS: Female sex, vertex presentation, normal delivery, rural birth, and discharge from hospital less than 4 days after birth all significantly increased the risk of late diagnosis of DDH. CONCLUSIONS: The results show differences in the risk factors for early and late diagnosed DDH. Some known risk factors for DDH are in fact protective for late diagnosis. These results highlight the need for broad newborn population screening and continued vigilance and training in screening programmes.

Age Distribution↗
PubMed2005

Effects of pre-eclampsia on maternal plasma, cerebrospinal fluid, and umbilical cord urotensin II concentrations: a pilot study.

BACKGROUND: Urotensin II (UII) is the most potent endogenous vasoconstrictor identified to date. Pre-eclampsia is associated with arteriolar vasospasm but the precise underlying mechanism is uncertain and we hypothesized that UII concentrations might also be elevated. In this study we measured UII concentrations in maternal plasma and cerebrospinal fluid (CSF), and umbilical vein plasma from pre-eclamptic (PET) and normotensive patients undergoing elective Caesarean section under spinal or combined spinal-epidural anaesthesia. METHODS: With LREC approval and informed consent we recruited two groups of 10 patients; control [mean (range) age, 29 (22-43) yr; BMI, 25 (20-32); gestation, 273 (267-281) days; mean arterial pressure (MAP) on day of delivery, 81 (75-96) mm Hg] and PET [age, 34 (22-40) yr; BMI, 25 (21-46); gestation, 253 (203-289) days; MAP on day of delivery, 106 (88-128) mm Hg]. Maternal blood and CSF samples and umbilical vein blood samples were taken. UII was extracted and concentrations measured using a radioimmunoassay. RESULTS: Two plasma and two CSF samples in the control and two CSF samples in the PET group were below the assay detection limits. There were no differences in maternal plasma or CSF or umbilical vein UII concentrations between the groups. However, there was a small ( approximately 40%) but significant increase in cord UII concentrations when compared with paired plasma in the PET group. There was a weak but significant negative correlation (r=-0.4, P=0.049) between cord UII concentrations and gestation in the PET group. In addition, we observed a significant positive correlation between plasma and CSF (r(2)=+0.57, P=0.0009, n=16), plasma and cord (r(2)=+0.43, P=0.0031, n=18) and CSF and cord (r(2)=+0.32, P=0.022, n=16) UII concentrations for the whole data set. CONCLUSIONS: Collectively the data indicate that UII concentrations do not increase in PET compared with controls but, in PET patients, cord UII concentrations are elevated relative to paired plasma samples. Elevated umbilical vein UII concentrations may simply indicate reduced placental viability and possibly UII metabolism as a result of reduced blood flow or possibly that the placenta is producing UII.

Adult↗
PubMed2005

A South Australian population-based study of congenital talipes equinovarus.

The aims of this study were to provide a population-based prevalence for congenital talipes equinovarus (CTEV), to conduct an epidemiological investigation into the risk factors for CTEV and describe associated features. The study used a retrospective case-control design of CTEV notified to the South Australian Birth Defects Register between 1986 and 1996 inclusive, linking characteristics of mother and baby from the perinatal data collection. The prevalence of isolated CTEV was 1.1/1000 total births (n = 231). Four factors were significantly associated with an increased risk of CTEV: maternal Aboriginal race (ORadj = 2.0; 95% CI 1.1, 3.6), male gender (ORadj = 2.4; 95% CI 1.8, 3.2), maternal anaemia (ORadj = 1.8; 95% CI 1.0, 2.9) and maternal hyperemesis (ORadj = 3.6; 95% CI 1.3, 9.8). The prevalence of CTEV associated with another birth defect or syndrome (n = 157) was 0.7/1000 total births. CTEV was associated with specific birth defects and also with oligohydramnios when another birth defect was present.

Anemia↗
PubMed2002

Iontophoretically applied lidocaine and the prevention of pain associated with the injection of intravenous propofol: a comparison with intravenous lidocaine.

BACKGROUND AND OBJECTIVE: Pain following the injection of propofol is a common problem. It is often treated by the coadministration of intravenous lidocaine. Iontophoresis, which facilitates the delivery of charged molecules such as lidocaine to body tissues, may be a practical alternative to lessen the pain. METHODS: The iontophoretic application of lidocaine was compared with intravenous lidocaine to assess the relative efficacy of reducing pain during propofol administration. RESULTS: The incidence rate of moderate or severe pain was significantly greater in the iontophoresis group (26.7 compared with 6.9% in the intravenous lidocaine group) (P < 0.05). CONCLUSIONS: The iontophoretic administration of lidocaine 60 mg does not compare favourably with lidocaine 40 mg mixed with propofol for the reduction of pain on administration of propofol.

Adolescent↗
PubMed2002

Intravesical pH: a potentially important variable affecting efficacy and the further development of anthracycline chemotherapy for superficial bladder cancer.

OBJECTIVE: To assess, using epirubicin-sensitive and multidrug resistant (MDR) derivatives of human bladder cancer cell lines in vitro, the probable effect of intravesical pH changes, with and without the MDR antagonist verapamil, on the uptake, intracellular distribution and cytotoxicity of epirubicin during intravesical chemotherapy. MATERIALS AND METHODS: Incubations for cytotoxicity testing were carried out in buffered medium containing epirubicin, at pH values of 6.0-8.5, with verapamil where appropriate. The cytotoxicity of epirubicin, with and without verapamil, was determined using the tetrazolium cytotoxicity assay. Intracellular epirubicin fluorescence was assessed using flow cytometry and confocal microscopy. Flow cytometric total intracellular epirubicin fluorescence was measured at pH 6.0, 6.4, 6.8, 7.2, and 7.6, and confocal microscopy was carried out at pH 6.0 and 8.0. The MDR-reversing agent verapamil was added at 100 micro g/mL to some incubations. RESULTS: Epirubicin cytotoxicity in resistant cell lines appears considerably enhanced by adding verapamil and further improved, especially in MDR cells, by alkalinization of the drug solution to pH 8.0. Flow cytometry results showed striking and consistent differences in epirubicin handling with pH. Sensitive cells can be induced to absorb considerably more drug at alkaline pH, whilst resistant cells show no such behaviour. Nuclear drug fluorescence was greater in sensitive cells at alkaline pH, but cytoplasmic drug fluorescence in the resistant cells was little changed by pH. Adding verapamil to resistant cells restored the sensitive phenotype of drug handling. CONCLUSION: Buffering epirubicin to an alkaline pH before intravesical application should increase its intrinsic cytotoxicity. The potential for synergy at certain drug combinations will be enhanced by applying these findings. MDR reversal and fatty acid augmentation of drug uptake are discussed as examples.

Administration, Intravesical↗
PubMed2002

Cross-talk between Msx/Dlx homeobox genes and vitamin D during tooth mineralization.

Rickets is associated with site-specific disorders of enamel and dentin formation, which may reflect the impact of vitamin D on a morphogenetic pathway. This study is devoted to potential cross-talk between vitamin D and Msx/Dlx transcription factors. We raised the question of a potential link between tooth defects seen in mice with rickets and Msx2 gene misexpression, using mutant mice lacking the nuclear vitamin D receptor as an animal model. Our data showed a modulation of Msx2 expression. In order to search for a functional impact of this Msx2 misexpression secondary to rickets, we focused our attention on osteocalcin as a target gene for both vitamin D and Msx2. Combining Msx2 overexpression and vitamin D addition in vitro, we showed an inhibitory effect on osteocalcin expression in immortalized MO6-G3 odontoblasts. Finally, in the same cells, such combinations appeared to modulate VDR expression outlining the existence of complex cross-regulations between vitamin D and Msx/Dix pathways.

Animals↗
PubMed2001

Buscopan for the treatment of pain after laparoscopic sterilisation.

We investigated the effect of Buscopan 20 mg, given at the end of surgery, on analgesic requirements in 44 ASA I and II patients presenting as day cases for laparoscopic sterilisation using Filshie clips. Patients were randomly allocated to receive either intravenous Buscopan 20 mg or saline placebo at the end of surgery. There was no significant difference in pain scores, analgesic requirements or the incidence of nausea and vomiting between the two groups. We conclude that intravenous Buscopan 20 mg was not effective for pain relief following laparoscopic sterilisation.

Adult↗
PubMed2001

Analgesia for circumcision in a paediatric population: comparison of caudal bupivacaine alone with bupivacaine plus two doses of clonidine.

BACKGROUND: Clonidine is often used to improve the duration and quality of analgesia produced by caudal epidural blockade, although the optimum dose of clonidine with bupivacaine remains uncertain. METHODS: We compared the effect of clonidine, 1 and 2 microg x kg(-1), added to bupivacaine (1.25 mg x kg(-1)) with that of bupivacaine alone in 75 male children undergoing elective circumcision. RESULTS: There was a trend towards increasing duration of analgesia with increasing dose of clonidine [group B (bupivacaine) 280.7 (171.6) min, C1 (bupivacaine + clonidine 1 microg x kg(-1)) 327.8 (188.3) min and C2 (bupivacaine + clonidine 2 microg x kg(-1)) 382.0 (200.6) min], although this difference was not statistically significant. Mean time to arousal from anaesthesia was significantly prolonged with clonidine 2 microg kg(-1) (group C2 21.3 (13-36) min, group C1 14.0 (6-25) min and group B 14.4 (2-32) min. Supplementary analgesic requirements and incidence of adverse effects were low, with no differences between the groups. CONCLUSIONS: For paediatric circumcision, under general anaesthesia, the addition of clonidine 2 microg x kg(-1) to low volume (0.5 ml x kg(-1)) caudal anaesthetics has a limited clinical benefit for children undergoing circumcision.

Adrenergic alpha-Agonists↗
PubMed2001

Changes in short-term power output in 10- to 12-year-olds.

In this study, we used multi-level regression modelling to assess the influence of age, sex, body size, skinfold thicknesses, maturity, thigh muscle volume and isokinetic leg strength on the development of load- and inertia-adjusted peak (1 s) and mean power (30 s) determined using the Wingate anaerobic test. Fifteen males and 19 females were measured twice, first aged 10.0 +/- 0.3 years and then aged 11.8 +/- 0.3 years. Initial models identified body mass and height as significant explanatory variables (P < 0.05) for peak power and mean power, with an additional age effect for the former. No significant differences between the sexes or maturity effects were observed for either peak or mean power (P > 0.05). The introduction of sum of skinfolds improved the fit of the model and rendered the height term non-significant for both peak and mean power (P> 0.05). An age effect became apparent for mean power. When isokinetic leg strength and thigh muscle volume were entered into the model, the latter exerted a significant effect on both peak and mean power (P< 0.05), whereas isokinetic leg strength was not a significant explanatory variable for either (P> 0.05). In conclusion, thigh muscle volume exerts a positive influence on young people's short-term power output, which is additional to the effects of body mass, sum of skinfolds and age.

Age Factors↗
PubMed2000

An automated system for the measurement of alanine/EPR dosimeters

NPL for several years has offered mailed reference dosimetry services based on alanine/EPR dosimeters, both at industrial and therapy dose levels. Compared to other methods of reference dosimetry, operator involvement in alanine/EPR has been found to be relatively high, and contributes significantly to the overall economics of the process. Commercially available sample changers are not suitable for high accuracy applications, and it has proved necessary to develop a dedicated automation system to handle NPL alanine dosimeter pellets. In this paper we describe an automatic sample changer for placing and retrieving alanine pellets into and out of the cavity of a standard research grade EPR spectrometer. Up to 32 pellets can be held in each removable sample tray. The sample changer software has been interfaced into the spectrometer control software to enable complete automation of the measurement process, including the optimization of spectrometer settings and rotation of the sample within the cavity.

Journal Article↗
PubMed2000

Assessment of abdominal fat development in young adolescents using magnetic resonance imaging.

OBJECTIVE: To determine the patterns of change and the best anthropometric indicators of intra-abdominal fat deposition in young adolescents from ages 11-13 y. SUBJECTS: Subjects were 25 boys (mean age 13.7 +/- 0.32 y) and 17 girls (mean age of 13.7 +/- 0.23 y) who had taken part in a similar study 2 y earlier at ages 11.5 +/- 0.33 y and 11.5 +/- 0.27 y, respectively. METHODS: Intra-abdominal (IA) and subcutaneous adipose (SA) tissue areas and IA/SA ratio were determined through four tranverse magnetic resonance imaging scans on two occasions. Differences were investigated using t-tests and ANOVA. Skinfolds, girths and circumferences, body mass index and hydrostatic weighing were also recorded. Pearson correlation coefficients and regression equations were calculated to determine the best anthropometric indicators of intra-abdominal fat deposition. RESULTS: Intra-abdominal fat and subcutaneous fat areas had significantly increased in boys and girls by the second measure. Boys had deposited greater amounts of fat in intra-abdominal depots so that their intra-abdominal/subcutaneous ratio had increased significantly from 0.31 to 0.39. This had reduced in girls from 0.39 to 0.35. However, patterns of change were variable within sexes. Truncal skinfold sites (r = 0.54-0.70) emerged as the best field indicators of intra-abdominal fat deposition. CONCLUSIONS: Patterns of intra-abdominal and subcutaneous fat distribution are identifiable in pubescent children using magnetic resonance imaging. An acceptable indication is provided by truncal skinfolds.

Abdomen↗
PubMed2000

Effect of meloxicam on postoperative pain after abdominal hysterectomy.

We studied 36 patients, allocated randomly to receive meloxicam 15 mg rectally (n = 18) or placebo suppository (n = 18) before total abdominal hysterectomy in a double-blind study. Visual analogue scores for pain at rest (P < 0.005), on movement (P < 0.05) and on coughing (P < 0.05) were significantly decreased in the meloxicam group during the first 24 h after surgery. Mean 24-h PCA morphine requirements were 33.2 (SD 16.9) mg and 38.2 (20.8) mg in the meloxicam and placebo groups, respectively (ns). There was no difference in the incidence of nausea, vomiting or sedation between groups.

Adult↗
PubMed2000

Epithelial Dlx-2 homeogene expression and cementogenesis.

The Dlx-2 (distal-less gene) homeoprotein transcription factor controls early tooth development but has not been studied during the late stages of biomineralization. Transgenic mice containing a Dlx-2/LacZ reporter construct were used to map the Dlx-2 expression pattern in cementoblasts, the dental cells most closely related to bone cells and therefore suggested to be uniquely positioned osteoblasts. During initial root formation, marked expression of Dlx-2 was evident in molar and incisor root epithelium, whereas dental papilla and follicle were negative. Dlx-2 was expressed in this epithelium from the apical loop to the area of its disruption. During acellular cementum formation in both incisors and molars, Dlx-2 expression was observed in the majority of differentiated cementoblasts from the apical region to the erupting zones. During cellular cementum formation, the presence of which characterizes growth-limited molars, Dlx-2 expression was restricted to the innermost cementoblasts and entrapped cementocytes. These data further support the hypothesis of a complex origin and fate of cementum-forming cells, as previously suggested by the expression patterns of a set of mesenchymal and epithelial markers, notably ameloblastin as shown here. Dlx-2 expression might constitute a landmark of cementoblast subpopulations of epithelial origin. (J Histochem Cytochem 48:277-283, 2000)

Aging↗
PubMed2000

Biomineralization, life-time of odontogenic cells and differential expression of the two homeobox genes MSX-1 and DLX-2 in transgenic mice.

Msx and Dlx homeobox genes encode for transcription factors that control early morphogenesis. More specifically, Msx-1, Msx-2, and Dlx-2 homeobox genes contribute to the initial patterning of the dentition. The present study is devoted to the potential role of those homeobox genes during the late formation of mineralized tissues, using the rodent incisor as an experimental system. The continuously erupting mandibular incisor allows (1) the coinvestigation of the whole sequences of amelogenesis and dentinogenesis, aligned along the main dental axis in a single sample in situ and (2) the differential characterization of transcripts generated by epithelial and ectomesenchymal odontogenic cells. Northern blot experiments on microdissected cells showed the continuing expression of Msx-2 and Dlx-2 in the later stages of dental biomineralization, differentially in epithelial and ectomesenchymal compartments. Transgenic mice produced with LacZ reporter constructs for Dlx-2 and Msx-1 were used to detect different components of the gene expression patterns with the sensitive beta-galactosidase histoenzymology. The results show a prominent epithelial involvement of Dlx-2, with stage-specific variations in the cells involved in enamel formation. Quantitative analyses identified specific modulations of Dlx-2 expression in ameloblasts depending on the anatomical sites of the incisor, showing more specifically an inverse linear relationship between the Dlx-2 promoter activity level and enamel thickness. This investigation extends the role of homeoproteins to postmitotic stages, which would control secretory cell activity, in a site-specific manner as shown here for Dlx-2.

Animals↗