Effects of Cold-Water Immersion Compared with Other Recovery Modalities on Athletic Performance Following Acute Strenuous Exercise in Physically Active Participants: A Systematic Review, Meta-Analysis, and Meta-Regression

BACKGROUND

Studies investigating the effects of common recovery modalities following acute strenuous exercise have reported mixed results.

OBJECTIVES

This systematic review with meta-analysis and meta-regression compared the effects of cold-water immersion (CWI) against other common recovery modalities on recovery of athletic performance, perceptual outcomes, and creatine kinase (CK) following acute strenuous exercise in physically active populations.

STUDY DESIGN

Systematic review, meta-analysis, and meta-regression.

METHODS

The MEDLINE, SPORTDiscus, Scopus, Web of Science, Cochrane Library, EmCare, and Embase databases were searched up until September 2022. Studies were included if they were peer reviewed, published in English, included participants who were involved in sport or deemed physically active, compared CWI with other recovery modalities following an acute bout of strenuous exercise, and included measures of performance, perceptual measures of recovery, or CK.

RESULTS

Twenty-eight studies were meta-analysed. CWI was superior to other recovery methods for recovering from muscle soreness, and similar to other methods for recovery of muscular power and flexibility. CWI was more effective than active recovery, contrast water therapy and warm-water immersion for most recovery outcomes. Air cryotherapy was significantly more effective than CWI for the promotion of recovery of muscular strength and the immediate recovery of muscular power (1-h post-exercise). Meta-regression revealed that water temperature and exposure duration were rarely exposure moderators.

CONCLUSION

CWI is effective for promoting recovery from acute strenuous exercise in physically active populations compared with other common recovery methods.

PROTOCOL REGISTRATION

Open Science Framework: https://doi.org/10.17605/OSF.IO/NGP7C.

Screening over Speech in Unselected Populations for Clinical Trials in AD (PROSPECT-AD): Study Design and Protocol

BACKGROUND

Speech impairments are an early feature of Alzheimer's disease (AD) and consequently, analysing speech performance is a promising new digital biomarker for AD screening. Future clinical AD trials on disease modifying drugs will require a shift to very early identification of individuals at risk of dementia. Hence, digital markers of language and speech may offer a method for screening of at-risk populations that are at the earliest stages of AD, eventually in combination with advanced machine learning. To this end, we developed a screening battery consisting of speech-based neurocognitive tests. The automated test performs a remote primary screening using a simple telephone.

OBJECTIVES

PROSPECT-AD aims to validate speech biomarkers for identification of individuals with early signs of AD and monitor their longitudinal course through access to well-phenotyped cohorts.

DESIGN

PROSPECT-AD leverages ongoing cohorts such as EPAD (UK), DESCRIBE and DELCODE (Germany), and BioFINDER Primary Care (Sweden) and Beta-AARC (Spain) by adding a collection of speech data over the telephone to existing longitudinal follow-ups. Participants at risk of dementia are recruited from existing parent cohorts across Europe to form an AD 'probability-spectrum', i.e., individuals with a low risk to high risk of developing AD dementia. The characterization of cognition, biomarker and risk factor (genetic and environmental) status of each research participants over time combined with audio recordings of speech samples will provide a well-phenotyped population for comparing novel speech markers with current gold standard biomarkers and cognitive scores.

PARTICIPANTS

N= 1000 participants aged 50 or older will be included in total, with a clinical dementia rating scale (CDR) score of 0 or 0.5. The study protocol is planned to run according to sites between 12 and 18 months.

MEASUREMENTS

The speech protocol includes the following neurocognitive tests which will be administered remotely: Word List [Memory Function], Verbal Fluency [Executive Functions] and spontaneous free speech [Psychological and/ or behavioral symptoms]. Speech features on the linguistic and paralinguistic level will be extracted from the recordings and compared to data from CSF and blood biomarkers, neuroimaging, neuropsychological evaluations, genetic profiles, and family history. Primary candidate marker from speech will be a combination of most significant features in comparison to biomarkers as reference measure. Machine learning and computational techniques will be employed to identify the most significant speech biomarkers that could represent an early indicator of AD pathology. Furthermore, based on the analysis of speech performances, models will be trained to predict cognitive decline and disease progression across the AD continuum.

CONCLUSION

The outcome of PROSPECT-AD may support AD drug development research as well as primary or tertiary prevention of dementia by providing a validated tool using a remote approach for identifying individuals at risk of dementia and monitoring individuals over time, either in a screening context or in clinical trials.

Impact of clinical symptoms and diagnosis: the electronic Person-Specific Outcome Measure (ePSOM) development programme

Introduction

Regulatory bodies recommend that outcome measures used in Alzheimer’s disease (AD) clinical trials capture clinically meaningful changes for the trial participant. However, commonly used outcome measures do not reflect the individual’s views on what matters to them individually. The aim of the electronic Person-Specific Outcome Measure (ePSOM) programme is to better understand what outcomes matter to patients in early Alzheimer’s disease.

Methods

As part of the ePSOM programme, we designed and ran an online study to understand what matters to individuals when developing new treatments for AD. The ePSOM survey ran Aug 2019–Dec 2019 (UK) and collected primarily free text responses which were analysed using Natural Language Processing (NLP) techniques. In this paper, we focus our analyses on individuals who reported having a neurodegenerative disease diagnosis (primarily Mild Cognitive Impairment (MCI) or AD), reporting the most frequent and most important brain health priorities for this group. Due to a small sample size, the Diagnosis group was analysed as a whole. Finally, we compared the Diagnosis group to an age and gender matched control group using chi-squared tests to look for any differences between the Diagnosis and control groups’ priorities.

Results

The survey was completed by 5808 respondents, of whom 167 (2.9%) (women n = 91, men n = 69, other n = 7) had received one of our pre-defined neurodegenerative disease diagnosis: most commonly MCI n = 52, 1.1% (mean age 69.42, SD = 10.8); or Alzheimer’s disease n = 48, 1.0% (mean age 71.24, SD = 9.79). Several thematic clusters were significantly more important for the target diagnostic group, e.g.: Expressing opinions; and less important, e.g., Cognitive Games.

Conclusion

We conclude there are a range of outcomes which individuals consider important and what potential new treatments should help maintain or improve, suggesting that outcomes that matter shift along the preclinical, prodromal and overt dementia continuum. This has important implications for the development of outcome measures in long term prevention studies that last several years where participants may pass through different stages of disease. In the final stage of our project, we will design an electronic outcomes app which will employ the methodology tested in the large-scale survey to capture what matters to individuals about their brain health at an individual level.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41687-022-00433-2.

Impact of Cold-Water Immersion Compared with Passive Recovery Following a Single Bout of Strenuous Exercise on Athletic Performance in Physically Active Participants: A Systematic Review with Meta-analysis and Meta-regression

Background

Studies investigating the effects of cold-water immersion (CWI) on the recovery of athletic performance, perceptual measures and creatine kinase (CK) have reported mixed results in physically active populations.

Objectives

The purpose of this systematic review was to investigate the effects of CWI on recovery of athletic performance, perceptual measures and CK following an acute bout of exercise in physically active populations.

Study Design

Systematic review with meta-analysis and meta-regression.

Methods

A systematic search was conducted in September 2021 using Medline, SPORTDiscus, Scopus, Web of Science, Cochrane Library, EmCare and Embase databases. Studies were included if they were peer reviewed and published in English, included participants who were involved in sport or deemed physically active, compared CWI with passive recovery methods following an acute bout of strenuous exercise and included athletic performance, athlete perception and CK outcome measures. Studies were divided into two strenuous exercise subgroups: eccentric exercise and high-intensity exercise. Random effects meta-analyses were used to determine standardised mean differences (SMD) with 95% confidence intervals. Meta-regression analyses were completed with water temperature and exposure durations as continuous moderator variables.

Results

Fifty-two studies were included in the meta-analyses. CWI improved the recovery of muscular power 24 h after eccentric exercise (SMD 0.34 [95% CI 0.06–0.62]) and after high-intensity exercise (SMD 0.22 [95% CI 0.004–0.43]), and reduced serum CK (SMD − 0.85 [95% CI − 1.61 to − 0.08]) 24 h after high-intensity exercise. CWI also improved muscle soreness (SMD − 0.89 [95% CI − 1.48 to − 0.29]) and perceived feelings of recovery (SMD 0.66 [95% CI 0.29–1.03]) 24 h after high-intensity exercise. There was no significant influence on the recovery of strength performance following either eccentric or high-intensity exercise. Meta-regression indicated that shorter time and lower temperatures were related to the largest beneficial effects on serum CK (duration and temperature dose effects) and endurance performance (duration dose effects only) after high-intensity exercise.

Conclusion

CWI was an effective recovery tool after high-intensity exercise, with positive outcomes occurring for muscular power, muscle soreness, CK, and perceived recovery 24 h after exercise. However, after eccentric exercise, CWI was only effective for positively influencing muscular power 24 h after exercise. Dose–response relationships emerged for positively influencing endurance performance and reducing serum CK, indicating that shorter durations and lower temperatures may improve the efficacy of CWI if used after high-intensity exercise.

Funding

Emma Moore is supported by a Research Training Program (Domestic) Scholarship from the Australian Commonwealth Department of Education and Training.

Protocol registration

Open Science Framework: 10.17605/OSF.IO/SRB9D.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-022-01644-9.

A UK-Wide Study Employing Natural Language Processing to Determine What Matters to People about Brain Health to Improve Drug Development: The Electronic Person-Specific Outcome Measure (ePSOM) Programme

BACKGROUND

It is important to use outcome measures for novel interventions in Alzheimer's disease (AD) that capture the research participants' views of effectiveness. The electronic Person-Specific Outcome Measure (ePSOM) development programme is underpinned by the need to identify and detect change in early disease manifestations and the possibilities of incorporating artificial intelligence in outcome measures.

OBJECTIVES

The aim of the ePSOM programme is to better understand what outcomes matter to patients in the AD population with a focus on those at the pre-dementia stages of disease. Ultimately, we aim to develop an app with robust psychometric properties to be used as a patient reported outcome measure in AD clinical trials.

DESIGN

We designed and ran a nationwide study (Aug 2019 - Nov 2019, UK), collecting primarily free text responses in five pre-defined domains. We collected self-reported clinical details and sociodemographic data to analyse responses by key variables whilst keeping the survey short (around 15 minutes). We used clustering and Natural Language Processing techniques to identify themes which matter most to individuals when developing new treatments for AD.

RESULTS

The study was completed by 5,808 respondents, yielding over 80,000 free text answers. The analysis resulted in 184 themes of importance. An analysis focusing on key demographics to explore how priorities differed by age, gender and education revealed that there are significant differences in what groups consider important about their brain health.

DISCUSSION

The ePSOM data has generated evidence on what matters to people when developing new treatments for AD that target secondary prevention and therein maintenance of brain health. These results will form the basis for an electronic outcome measure to be used in AD clinical research and clinical practice.

Involving research participants in a pan-European research initiative: the EPAD participant panel experience

BACKGROUND

Including participants in patient and public involvement activities is increasingly acknowledged as a key pillar of successful research activity. Such activities can influence recruitment and retention, as well as researcher experience and contribute to decision making in research studies. However, there are few established methodologies of how to set up and manage participant involvement activities. Further, there is little discussion of how to do so when dealing with collaborative projects that run across countries and operate in multiple linguistic and regulatory contexts.

METHODS

In this paper we describe the set-up, running and experiences of the EPAD participant panel. The EPAD study was a pan-European cohort study with the aim to understand risks for developing Alzheimer's disease and build a readiness cohort for Phase 2 clinical trials. Due to the longitudinal nature of this study, combined with the enrolment of healthy volunteers and those with mild cognitive impairments, the EPAD team highlighted participant involvement as crucial to the success of this project. The EPAD project employed a nested model, with local panels meeting in England, France, Scotland, Spain and The Netherlands, and feeding into a central study panel. The local panels were governed by terms of reference which were adaptable to local needs.

RESULTS

The impact of the panels has been widespread, and varies from feedback on documentation, to supporting with design of media materials and representation of the project at national and international meetings.

CONCLUSIONS

The EPAD panels have contributed to the success of the project and the model established is easily transferable to other disease areas investigating healthy or at-risk populations.

Outbreak of Campylobacteriosis Associated with Raccoon Contact at a Wildlife Rehabilitation Centre, Minnesota, 2013

Campylobacteriosis is an enteric illness caused by bacteria of the genus Campylobacter. There are approximately 900 culture-confirmed cases of campylobacteriosis reported annually to the Minnesota Department of Health (MDH). Case patients are interviewed about risk factors, including foods eaten, recreational and drinking water exposures and animal contact. In September 2013, MDH identified two Campylobacter jejuni cases who reported working at the same wildlife rehabilitation centre before illness onset. This report describes the investigation, which used a case-control study design, and identified 16 additional ill persons, for a total of 18 ill persons. Both cases and controls reported working with a variety of animals, including squirrels, chipmunks, mice, raccoons, opossums, rabbits, songbirds, waterfowl and reptiles. In univariate analyses, contact with a number of different animal species was significantly associated with illness, including raccoons (odds ratio [OR], 11.1; P < 0.001), chipmunks (OR, 3.65; P = 0.01), opossums (OR, 4.38; P = 0.005), mice (OR, 4.18; P = 0.01) and rabbits (OR, 4.36; P = 0.003). In a multivariate model, contact with raccoons was the only exposure independently associated with illness (adjusted OR, 12.2; P = 0.01). Bacterial culture and subtyping of the outbreak strain of C. jejuni from raccoon faecal samples further implicated raccoons as the source of the outbreak. Not all of the cases reported handling raccoons, suggesting that environmental contamination contributed to transmission. MDH worked with the wildlife rehabilitation centre's management to strengthen biosecurity and infection control protocols.

CFD for wastewater treatment: an overview

Computational fluid dynamics (CFD) is a rapidly emerging field in wastewater treatment (WWT), with application to almost all unit processes. This paper provides an overview of CFD applied to a wide range of unit processes in water and WWT from hydraulic elements like flow splitting to physical, chemical and biological processes like suspended growth nutrient removal and anaerobic digestion. The paper's focus is on articulating the state of practice and research and development needs. The level of CFD's capability varies between different process units, with a high frequency of application in the areas of final sedimentation, activated sludge basin modelling and disinfection, and greater needs in primary sedimentation and anaerobic digestion. While approaches are comprehensive, generally capable of incorporating non-Newtonian fluids, multiphase systems and biokinetics, they are not broad, and further work should be done to address the diversity of process designs. Many units have not been addressed to date. Further needs are identified throughout, but common requirements include improved particle aggregation and breakup (flocculation), and improved coupling of biology and hydraulics.

UK service level audit of insulin pump therapy in paediatrics

AIM

To conduct an audit of insulin pump therapy in the UK after the issue of guidelines for the use of continuous subcutaneous insulin infusion by NICE in 2008 (Technology Appraisal 151).

METHODS

All centres in the UK, providing pump services to children and young people were invited to participate in an online audit. Audit metrics were aligned to NICE Technology Appraisal 151 and an electronic data collection tool was used.

RESULTS

Of the 176 UK centres identified as providing pump services, 166 (94.3%) participated in the study. A total of 5094 children and young people were identified as using continuous subcutaneous insulin infusion (19% of all paediatric patients with Type 1 diabetes), with a median (range) of 16.9 (0.67-69.4)% per centre. Units had a median of 0.58 consultant sessions, 0.43 full-time equivalent diabetic specialist nurses, and 0.1 full-time equivalent dieticians delivering the pump service. The majority of this time was not formally funded. Families could access 24-h clinical and technical support (83% units), although the delivery varied between consultant, diabetic specialist nurse and company representatives. Only 53% of units ran, or accessed, structured education programmes for continuous subcutaneous insulin infusion use. Most units (86%) allowed continuous subcutaneous insulin infusion use for paediatric inpatients, but only 56% had written guidelines for this scenario. Nine percent of units had encountered funding refusal for a patient fulfilling NICE (Technology Appraisal 151) criteria.

CONCLUSION

The number of children and young people on continuous subcutaneous insulin infusion therapy is consistent with numbers estimated by NICE. There is a worrying lack of funded healthcare professional time. The audit also identified gaps in the provision of structured education and absence of written inpatient guidelines.

The U.K. service level audit of insulin pump therapy in adults

AIMS

The National Institute for Health and Clinical Excellence (NICE) published guidelines for the use of continuous subcutaneous insulin infusion in 2008 (technology appraisal 151). The first U.K.-wide insulin pump audit took place in 2012 with the aim of determining adherence to the guidance issued in NICE technology appraisal 151. The results of the adult service level audit are reported here.

METHODS

All centres providing continuous subcutaneous insulin infusion services to adults with diabetes in the U.K. were invited to participate. Audit metrics were aligned to technology appraisal 151. Data entry took place online using a DiabetesE formatted data collection tool.

RESULTS

One hundred and eighty-three centres were identified as delivering adult continuous subcutaneous insulin infusion services in the U.K., of which 178 (97.3%) participated in the audit. At the time of the audit, 13 428 adults were using insulin pump therapy, giving an estimated prevalence of use of 6%. Ninety-three per cent of centres did not report any barriers in obtaining funding for patients who fulfilled NICE criteria. The mean number of consultant programmed activities dedicated to continuous subcutaneous insulin infusion services was 0.96 (range 0-8), mean whole-time equivalent diabetes specialist nurses was 0.62 (range 0-3) and mean whole-time equivalent dietitian services was 0.3 (range 0-2), of which 39, 61 and 60%, respectively, were not formally funded.

CONCLUSIONS

The prevalence of continuous subcutaneous insulin infusion use in the U.K. falls well below the expectation of NICE (15-20%) and that of other European countries (> 15%) and the U.S.A. (40%). This may be attributable, in part, to lack of healthcare professional time needed for identification and training of new pump therapy users.

A protocol for the use of computational fluid dynamics as a supportive tool for wastewater treatment plant modelling

To date, computational fluid dynamics (CFD) models have been primarily used for evaluation of hydraulic problems at wastewater treatment plants (WWTPs). A potentially more powerful use, however, is to simulate integrated physical, chemical and/or biological processes involved in WWTP unit processes on a spatial scale and to use the gathered knowledge to accelerate improvement in plant models for everyday use, that is, design and optimized operation. Evolving improvements in computer speed and memory and improved software for implementing CFD, as well as for integrated processes, has allowed for broader usage of this tool for understanding, troubleshooting, and optimal design of WWTP unit processes. This paper proposes a protocol for an alternative use of CFD in process modelling, as a way to gain insight into complex systems leading to improved modelling approaches used in combination with the IWA activated sludge models and other kinetic models.

Sex-specific quantitative trait loci linked to autoresuscitation failure in SWR/J mice

Autoresuscitation (AR) is a highly conserved response among mammals, which allows survival from transient extreme hypoxia. During hypoxia, bradycardia, and hypoxic gasping develop after a brief period of hyperactivity. Normally, AR occurs if oxygen is restored during the gasping period where an initial heart rate increase is rapidly followed resumption or eupneic breathing. Humans and other mammals can survive multiple immediately repeated AR. A defective AR capacity has been implicated in Sudden Infant Death Syndrome. We had reported earlier that inbred strains of mice such as BALB/cJ could survive a characteristic number of immediately repeated AR trials, but that SWR/J mice failed to AR from a single hypoxic episode. We now report that strains closely related to SWR/J, FVB/N and SJL/J exhibit partial resuscitation defects relative to BALB/cJ or other mouse strains, establishing a genetic basis for variation in AR failure. The AR trial phenotype of BALB/cJ x SWR/J intercross F(1) and F(2) mice was consistent with BALB/cJ dominance and a discrete number of loci. Genome-wide mapping conducted with 60 intercross F(2) animals linked two loci to the number of AR trials survived, including one sex-specific locus with male expression, consistent with the observed 50% male bias for Sudden Infant Death Syndrome in humans. A locus carried on SWR/J chromosome 10 seems to be particularly important in AR failure and was confirmed in a partial consomic line. These results establish a genetic basis for AR failure phenotype in mice, with relevance to Sudden Infant Death Syndrome.

The presence of a BCR-ABL mutant allele in CML does not always explain clinical resistance to imatinib

The expansion of a leukemia clone bearing a Bcr-Abl kinase domain mutation is associated with acquired resistance to imatinib and may also predict disease progression in patients with Philadelphia-positive chronic myeloid leukemia (CML). Here we report results of pyrosequencing to quantitate the non-mutated and mutant alleles in 12 CML patients monitored over periods ranging from 11 to 58 months, and describe three contrasting kinetic patterns: Group 1 - in four patients total BCR-ABL transcript numbers remained high with the mutant allele predominating; Group 2 - in four patients the total number of BCR-ABL transcripts fell to low levels but the mutant allele predominated; and Group 3 - in four other patients the total level of transcripts remained high (n = 2) or fell (n = 2) but the mutant clone persisted at relatively low level. In Group 2 the mutant leukemia clone was presumably still relatively sensitive to imatinib but in Group 1 the leukemia could be classified as resistant. In Group 3 patients the imatinib sensitivity of the leukemia was variable. We conclude that a mutant clone does not necessarily have a proliferative advantage and its presence does not always account for resistance to imatinib. Other mechanisms underlie resistance in at least some patients.

Monitoring patients in complete cytogenetic remission after treatment of CML in chronic phase with imatinib: patterns of residual leukaemia and prognostic factors for cytogenetic relapse

We monitored BCR-ABL transcript levels by quantitative real-time PCR in 103 patients treated with imatinib for chronic myeloid leukaemia in chronic phase for a median of 30.3 months (range 5.5-49.9) after they achieved complete cytogenetic remission (CCyR). The patients could be divided into three groups: (1) in 32 patients transcript levels continued to decline during the period of observation (nadir BCR-ABL/ABL ratio 0.015%); in five of these patients BCR-ABL transcripts became undetectable on repeated testing, (2) in 42 patients the transcript levels reached a plateau and (3) in 26 patients transcript numbers increased and the initial CCyR was lost. Three patients were not evaluable. Patients who remained in CCyR for at least 24 months appeared to have a low risk of subsequent cytogenetic relapse. We conclude that the pattern of 'residual' disease after achieving CCyR on imatinib is variable: some patients in CCyR show a progressive reduction in the level of residual disease, some reach a plateau where transcript numbers are relatively stable and others relapse with Ph-positive metaphases.

Hospital in-patients with diabetes: increasing prevalence and management problems

AIMS

To re-assess the prevalence, management problems, clinical outcomes and discharge summaries of hospital in-patients with diabetes.

METHODS

Case records of all patients occupying in-patient beds were audited on a single weekday in 2003 in a large urban hospital and repeated after 3 months. Data was compared with an identical audit 12 years previously.

RESULTS

Over 12 years the number of beds available for admission (1191) had reduced by 25% with a bed occupancy of 97%. Diabetes prevalence had increased from 7.0% to 11.1% (P < 0.01) (97% Type 2). Diabetes management was considered inappropriate in 29%, more than in 1991 (20%). After 3 months, discharge summaries had been completed on 75% of patients but diabetes was mentioned in only 53%.

CONCLUSION

The prevalence of in-patient diabetes (11.1%) was over 50% greater and diabetes management was suboptimal in more patients than in 1991. In many length of stay was prolonged and almost half of the discharge summaries did not mention diabetes. These findings have major implications for service delivery and resource planning.

Within- and between-laboratory precision in the measurement of body volume using air displacement plethysmography and its effect on body composition assessment

OBJECTIVE

To determine and compare the extent of within- and between-laboratory precision in body volume (BV) measurements using air displacement plethysmography (ADP), the BOD POD body composition system, and to interpret any such variability in terms of body composition estimates.

DESIGN

Repeated test procedures of BV assessment using the BOD POD ADP were reproduced at two laboratories for the estimation of precision, both within and between laboratories.

SUBJECTS

In total, 30 healthy adult volunteers, 14 men (age, 19-48 y; body mass index (BMI), 19.7-30.3 kg/m2) and 16 women (age, 19-40 y; BMI, 16.3-35.7 kg/m2), were each subjected to two test procedures at both laboratories. Two additional volunteers were independently subjected to 10 repeated test procedures at both laboratories.

MEASUREMENTS

Repeated measurements of BV, uncorrected for the effects of isothermal air in the lungs and the surface area artifact, were obtained using the BOD POD ADP, with the identical protocol being faithfully applied at both laboratories. Uncorrected BV measurements were adjusted to give estimates of actual BV that were used to calculate body density (body weight (BWt)/actual BV) from which estimates of body composition were derived. The differences between repeated BV measurements or body composition estimates were used to assess within-laboratory precision (repeatability), as standard deviation (SD) and coefficient of variation; the differences between measurements reproduced at each laboratory were used to determine between-laboratory precision (reproducibility), as bias and 95% limits of agreement (from SD of the differences between laboratories).

RESULTS

The extent of within-laboratory methodological precision for BV (uncorrected and actual) was variable according to subject, sample group and laboratory conditions (range of SD, 0.04-0.13 l), and was mostly due to within-individual biological variability (typically 78-99%) rather than to technical imprecision. There was a significant (P<0.05) bias between laboratories for the 10 repeats on the two independent subjects (up to 0.29 l). Although no significant bias (P=0.077) was evident for the sample group of 30 volunteers (-0.05 l), the 95% limits of agreement were considerable (-0.68 to 0.58 l). The effects of this variability in BV on body composition were relatively greater: for example, within-laboratory precision (SD) for body fat as % BWt was between 0.56 and 1.34% depending on the subject and laboratory; the bias (-0.59%) was not significant between laboratories, but there were large 95% limits of agreement (-3.67 to 2.50%).

CONCLUSION

Within-laboratory precision for each BOD POD instrument was reasonably good, but was variable according to the prevailing conditions. Although the bias between the two instruments was not significant for the BV measurements, implying that they can be used interchangeably for groups of similar subjects, the relatively large 95% limits of agreement indicate that greater consideration may be needed for assessing individuals with different ADP instruments. Therefore, use of a single ADP instrument is apparently preferable when assessing individuals on a longitudinal basis.

An unusual epistaxis

The case of a man who presented complaining of epistaxis is reported. He had coarctation repair 18 years previously. Subsequent investigation revealed an aortobronchial fistula resulting from false aneurysm formation distal to the original vessel anastamosis. This was repaired at surgery, the patient suffering a minor stroke, before rehabilitation and good recovery.

Cardiovascular effects of carbon monoxide and cigarette smoking

OBJECTIVES

This study was designed to compare the effects of inhaled carbon monoxide (CO), administered to achieve concentrations similar to those found in cigarette smoking, with the effects of cigarette smoking and air inhalation on heart rate and blood pressure, catecholamine release, platelet activation and C-reactive protein (CRP), a marker of inflammation.

BACKGROUND

Carbon monoxide may contribute to smoking-induced cardiovascular disease. Exposure to environmental CO has been associated with increased cardiovascular morbidity and mortality. Animal and in vitro studies suggest that CO may contribute to atherosclerosis and endothelial injury. There is conflicting evidence about the hemodynamic consequences of exposure to CO and its role in platelet activation.

METHODS

In a single-blind, crossover design, 12 healthy smokers inhaled CO at 1,200 ppm to 1,500 ppm to simulate CO intake from cigarette smoking, inhaled air on a similar schedule and smoked 20 cigarettes per day, each for seven days. Mean carboxyhemoglobin was 5 +/- 1% on CO treatment, 6 +/- 1% while smoking and 0.4 +/- 0.2% on air inhalations.

RESULTS

There was no difference in blood pressure between the treatments. Mean heart rate was higher during cigarette smoking compared with CO and air inhalations (75 beats/min vs. 66 beats/min; p < 0.05). Plasma levels of platelet factor 4 and CRP and urine epinephrine and norepinephrine were higher while smoking, with no effect of CO compared with air.

CONCLUSIONS

Carbon monoxide administered under conditions similar to those of cigarette smoking had no significant effect on blood pressure, heart rate, plasma catecholamines, platelet aggregation or CRP. The short-term chronotropic effect, adrenergic-activating, platelet-activating and CRP-increasing effects of smoking in healthy smokers are probably due to components of cigarette smoke other than CO.

Simpson Golabi Behmel syndrome: progress toward understanding the molecular basis for overgrowth, malformation, and cancer predisposition

Simpson Golabi Behmel syndrome (SGBS) is a complex congenital overgrowth syndrome with features that include macroglossia, macrosomia, and renal and skeletal abnormalities as well as an increased risk of embryonal cancers. Most cases of SGBS appear to arise as a result of either deletions or point mutations within the glypican-3 (GPC3) gene at Xq26, one member of a multigene family encoding for at least six distinct glycosylphophatidylinositol-linked cell surface heparan sulfate proteoglycans. As a class of molecules, heparan sulfate proteoglycans have been found to play essential roles in development by modulating cellular responses to growth factors and morphogens. Specifically, mutations in both the murine GPC3 gene and the Drosophila glypican, dally, have been found to modify cellular responses to bone morphogenetic proteins, providing important clues to the molecular basis of SGBS in humans. Despite these advances, there remains a paucity of information about the natural history of SGBS and optimal medical management strategies, and whether select mutations influence the SGBS phenotype and risk of cancer. To this end, an International SGBS Registry has been created and is being maintained to improve the clinical care and understanding of the pathogenesis of SGBS. Using an integrated approach employing epidemiology, molecular genetic characterization of specific GPC3 mutations, and the use of model organisms should rapidly expand the understanding of this complex disorder.

glypican-3 controls cellular responses to Bmp4 in limb patterning and skeletal development

Glypicans represent a family of six cell surface heparan sulfate proteoglycans in vertebrates. Although no specific in vivo functions have thus far been described for these proteoglycans, spontaneous mutations in the human and induced deletions in the mouse glypican-3 (Gpc3) gene result in severe malformations and both pre- and postnatal overgrowth, known clinically as the Simpson-Golabi-Behmel syndrome (SGBS). Mice carrying mutant alleles of Gpc3 created by either targeted gene disruption or gene trapping display a wide range of phenotypes associated with SGBS including renal cystic dysplasia, ventral wall defects, and skeletal abnormalities that are consistent with the pattern of Gpc3 expression in the mouse embryo. Previous studies in Drosophila have implicated glypicans in the signaling of decapentaplegic, a BMP homolog. Our experiments with mice show a significant relationship between vertebrate BMP signaling and glypican function; GPC3-deficient animals were mated with mice haploinsufficient for bone morphogenetic protein-4 (Bmp4) and their offspring displayed a high penetrance of postaxial polydactyly and rib malformations not observed in either parent strain. This previously unknown link between glypican-3 and BMP4 function provides evidence of a role for glypicans in vertebrate limb patterning and skeletal development and suggests a mechanism for the skeletal defects seen in SGBS.

GPC6, a novel member of the glypican gene family, encodes a product structurally related to GPC4 and is colocalized with GPC5 on human chromosome 13

Glypicans are a family of cell surface heparan sulfate proteoglycans that appear to play an important role in cellular growth control and differentiation, as is supported by the observation that mutations in GPC3 are responsible for Simpson-Golabi-Behmel syndrome (SGBS) in humans. Recently it has been shown that the GPC4 gene is tightly clustered with GPC3 on the X chromosome and that some patients with SGBS apparently have deletions affecting both genes. We report here the identification of a human cDNA encoding a novel glypican family member, glypican-6. This cDNA encodes a predicted protein of 554 amino acids and is structurally analogous to other members of the glypican gene family, but most highly related to glypican-4. A single GPC6 mRNA of 6.2 kb is detected most abundantly in the ovary, liver, and kidney, with lower levels of mRNA expression also detected in a wide range of other adult tissues. Radiation hybrid analysis mapped the GPC6 gene to human chromosome 13 very near the GPC5 gene, a member of the glypican family bearing strong similarity to GPC3.

Response to intradialytic parenteral nutrition

Malnutrition is a major clinical problem in patients receiving maintenance hemodialysis and has adverse effects on survival. Nutritional intervention is indicated, and there is evidence that intradialytic parenteral nutrition can be beneficial. We describe the application of a formal policy regarding the use of intradialytic parenteral nutrition and the beneficial effects on nutrition in the first four patients managed in this fashion. However, the fifth patient did not respond to parenteral nutrition, despite adequate dialysis. This prompted further investigation, and the patient was shown to have extensive gastric malignancy. This report shows that establishing a protocol for intradialytic parenteral nutrition is possible in a medium-sized hemodialysis unit. In these circumstances, nonresponse to this intervention should always be investigated to determine if there is another underlying cause of malnutrition unrelated to renal failure.

Evaluation of risk assessment questions used to target blood lead screening in Illinois

OBJECTIVE

Beginning in 1995, Illinois law permitted targeted-as opposed to universal-blood lead screening in low-risk areas, which were defined by ZIP code characteristics. State guidelines recommended specific lead risk assessment questions to use when targeting screening. This study was designed to evaluate the sensitivity and specificity of Illinois lead risk assessment questions.

DESIGN

Parents bringing their 9- or 10- or 12-month and 24-month-old children for health supervision visits at 13 pediatric practices and parents of children (aged 6 through 25 months and who needed a blood lead test) receiving care at 5 local health departments completed a lead risk assessment questionnaire concerning their child. Children had venous or capillary blood lead testing. Venous confirmation results of children with a capillary level >/=10 micrograms/dL were used in analyses.

CHILDREN

There were 460 children with both blood and questionnaire data recruited at the pediatric practices (58% of eligible) and 285 children (51% of eligible) recruited at local health departments. Of the 745 children studied, 738 provided a ZIP code that allowed their residence to be categorized as in a low-risk (n = 456) or high-risk (n = 282) area.

RESULTS

Sixteen children (3.5%) living in low-risk areas versus 34 children (12.1%) living in high-risk areas had a venous blood lead level (BLL) >/=10 micrograms/dL; 1.8% and 5.3%, respectively, had a venous BLL >/=15 micrograms/dL. For children living in low-risk areas, Illinois mandated risk assessment questions (concerning ever resided in home built before 1960, exposure to renovation, and exposure to adult with a job or hobby involving lead) had a combined sensitivity of.75 for levels >/=10 micrograms/dL and.88 for levels >/=15 micrograms/dL; specificity was.39 and.39, respectively. The sensitivity of these questions was similar among children from high-risk areas; specificity decreased to.27 and.28, for BLLs >/=10 micrograms/dL and >/=15 micrograms/dL, respectively. The combination of items requiring respondents to list house age (built before 1950 considered high risk) and indicate exposure to renovation had a sensitivity among children from low-risk areas of.62 for BLLs >/=10 micrograms/dL with specificity of.57; sensitivity and specificity among high-risk area children were.82 and.36, respectively. For this strategy, similar sensitivities and specificities for low and high-risk areas were found for BLLs >/=15 micrograms/dL.

CONCLUSIONS

The Illinois lead risk assessment questions identified most children with an elevated BLL. Using these questions, the majority of Illinois children in low-risk areas will continue to need a blood lead test. This first example of a statewide screening strategy using ZIP code risk designation and risk assessment questions will need further refinement to limit numbers of children tested. In the interim, this strategy is a logical next step after universal screening.

Learning leadership: students' experiences of a midwifery mentoring practicum

A leadership mentoring practicum is described wherein nurse-midwifery students are placed with leader/mentors at the state, regional, and national levels of organizations. Logs are kept by the students and discussions at student-faculty seminars focus on linking leadership theory to observations of leadership qualities and behaviours in the mentors. A profile of a "composite leader" derived from the students' experience experiences is presented.

Two quantitative methods for rib seriation in human skeletal remains

Accurate rib sequencing is of importance to both forensic anthropologists and human osteologists, but until recently there have been few traits used to aid in the seriation of ribs within a human burial. This study examines two measurements (head to tubercle length and superior costotransverse ligament crest height) for the purpose of aiding rib identification and seriation in human skeletal remains. A sample of 344 ribs from 43 individuals from the 19th century Anglican Church cemetery of St. Thomas in Belleville, Ontario were used for the current study. While the head to tubercle length appeared unreliable for rib seriation, the superior costotransverse ligament crest height may provide an alternative technique for assessing rib sequence. More importantly though, the method provides a basis on which the identification of the central ribs can be made.

Expression of the cell surface proteoglycan glypican-5 is developmentally regulated in kidney, limb, and brain

Heparan sulfate is ubiquitous at the cell surface, where it is expressed predominantly on proteoglycans of either the transmembrane syndecan family or the glycosylphosphatidylinositol (GPI)-anchored glypican family, and has been proposed to function as a "coreceptor" for a number of "heparin-binding" growth factors. Although little is known about functional differences between individual members of the glypican gene family, mutations in both the Drosophila gene dally and the human gene for glypican-3 strongly suggest that at least some glypicans do function in cellular growth control and morphogenesis. In particular, deletion of the human glypican-3 gene is responsible for Simpson-Golabi-Behmel syndrome, and its associated pre- and postnatal tissue overgrowth, increased risk of embryonal tumors during early childhood, and numerous visceral and skeletal anomalies. We have identified and characterized, by sequencing of EST clones and products of rapid amplification of cDNA ends (RACE), an mRNA that encodes a 572-amino-acid member of the glypican gene family (glypican-5) that is most related (50% amino acid similarity, 39% identity) to glypican-3. Glypican-5 mRNA is detected as a 3.9- and 4.4-kb transcript in adult and neonatal mouse brain total RNA, and in situ hybridization results localize transcript primarily to restricted regions of the developing central nervous system, limb, and kidney in patterns consistent with a role in the control of cell growth or differentiation. Interestingly, glypican-5 localizes to 13q31-32 of the human genome, deletions of which are associated with human 13q- syndrome, a developmental disorder with a pattern of defects that shows significant overlap with the pattern of glypican-5 expression.