Health care, federalism and the new Social Union

The Social Union framework agreement and the Health Accord provide examples of the close relationship that exists between federalism and the delivery of health care. These recent agreements represent a move from a federal-unilateral style of federalism to a more collaborative model. This shift will potentially affect federal funding for health care, interpretation of the Canada Health Act and the development of new health care initiatives. The primary advantage of the new collaborative model is protection of jurisdictional autonomy. Its primary disadvantages are blurring of accountability and potential for exclusion of the public from decision-making.

Effect of smoking cessation on mortality after myocardial infarction: meta-analysis of cohort studies

OBJECTIVE

To determine the effect of smoking cessation on mortality after myocardial infarction.

DATA SOURCES

English- and non-English-language articles published from 1966 through 1996 retrieved using keyword searches of MEDLINE and EMBASE supplemented by letters to authors and searching bibliographies of reviews.

STUDY SELECTION

Selection of relevant abstracts and articles was performed by 2 independent reviewers. Articles were chosen that reported the results of cohort studies examining mortality in patients who quit vs continued smoking after myocardial infarction.

DATA EXTRACTION

Mortality data were extracted from the selected articles by 2 independent reviewers.

DATA SYNTHESIS

Twelve studies were included containing data on 5878 patients. The studies took place in 6 countries between 1949 and 1988. Duration of follow-up ranged from 2 to 10 years. All studies showed a mortality benefit associated with smoking cessation. The combined odds ratio based on a random effects model for death after myocardial infarction in those who quit smoking was 0.54 (95% confidence interval, 0.46-0.62). Relative risk reductions across studies ranged from 15% to 61%. The number needed to quit smoking to save 1 life is 13 assuming a mortality rate of 20% in continuing smokers. The mortality benefit was consistent regardless of sex, duration of follow-up, study site, and time period.

CONCLUSION

Results of several cohort studies suggest that smoking cessation after myocardial infarction is associated with a significant decrease in mortality.

Diagnostic evaluation of patients with blunt abdominal trauma: a decision analysis

OBJECTIVES

Using decision analysis, to compare the expected utility (EU) of diagnostic peritoneal lavage (DPL), computed tomography (CT), and ultrasonography (US) to determine the optimal modality for the evaluation of blunt abdominal trauma (BAT) in hemodynamically stable adults.

METHODS

Data points for the decision analysis were obtained from three sources: 1) prevalence of BAT and the sensitivity and specificity of each diagnostic modality were determined through a criteria-based review of the literature; 2) rate of BAT necessitating immediate intervention, perioperative complication rate, and operative mortality rate were calculated using data from the authors' institution's trauma registry; and 3) outcome utilities were determined by telephone survey of adults in a random sample of households in the region. The decision tree was constructed and evaluated in standard fashion. For each diagnostic modality, the authors calculated the EU using the minimum, mean, and maximum sensitivity and specificity across a range of prevalence. Mean outcome utilities were used for each branch of the tree when calculating the EU.

RESULTS

The EU of CT was consistently lower than the EUs of DPL and US at all levels of prevalence. However, the rank order of the EUs of US and DPL varied with the prevalence of BAT. When the prevalence was <30%, the EU of US was higher than that for DPL. When the prevalence was 30-40%, the EUs were similar. When the prevalence was >40%, the EU of US was less than that of DPL.

CONCLUSIONS

Among institutions operating under constraints similar to those used in this model, the optimal diagnostic modality for the evaluation of BAT can be determined based on the sensitivity and specificity of the modality at their institution and the prevalence of BAT in their patient population.

Restructuring public health in Ontario: implications for heart health promotion

Community-based heart health promotion is viewed as an effective means of reducing cardiovascular disease risk. Although public health agencies have a central role in the implementation and dissemination of heart health programmes, their effectiveness is being challenged by major structural changes to Provincial public health systems across Canada, although the impacts of the changes have received relatively little attention in the research literature. As part of the Canadian Heart Health Initiative--Ontario Project (CHHIOP), this study used a qualitative approach to address the perceived implications of these changes to Ontario's public health system for heart health promotion. Interviews (n = 38) were conducted in eight public health units with staff most familiar with managing and/or delivering heart health activities. The results are mixed; that is, while many see the future of heart health promotion programming in Ontario as being at risk, others see recent changes as a step forward toward their institutionalization, particularly in light of recent funding decisions made by the Ministry of Health's Health Promotion Branch.

Restructuring public health in Ontario: implications for heart health promotion

Community-based heart health promotion is viewed as an effective means of reducing cardiovascular disease risk. Although public health agencies have a central role in the implementation and dissemination of heart health programmes, their effectiveness is being challenged by major structural changes to Provincial public health systems across Canada, although the impacts of the changes have received relatively little attention in the research literature. As part of the Canadian Heart Health Initiative--Ontario Project (CHHIOP), this study used a qualitative approach to address the perceived implications of these changes to Ontario's public health system for heart health promotion. Interviews (n = 38) were conducted in eight public health units with staff most familiar with managing and/or delivering heart health activities. The results are mixed; that is, while many see the future of heart health promotion programming in Ontario as being at risk, others see recent changes as a step forward toward their institutionalization, particularly in light of recent funding decisions made by the Ministry of Health's Health Promotion Branch.

Employment satisfaction of individuals with spinal cord injury

OBJECTIVES

Community reentry after a spinal cord injury is a long-term integrative process, because individuals must adjust to an extraordinary new set of circumstances. In this study, quality-of-life and work satisfaction variables associated with employed or unemployed individuals with spinal cord injury were examined.

METHODS

Quality-of-life and work satisfaction variables associated with 109 employed or unemployed individuals with spinal cord injury were examined by using an employment satisfaction survey.

RESULTS

Most of those employed indicated that they would either change jobs or some employment variable such as duties, supervisor, or hours worked. Participants who were not working attributed unemployment to an array of factors including ongoing health problems, lack of transportation, and impact of and/or lost disability benefits. Both groups offered feedback related to information provided to them by medical professionals about return-to-work resources.

CONCLUSIONS

The following three themes emerged from this analysis: (1) more comprehensive provider training about spinal cord injury is needed; (2) increased communication between consumer and family would be beneficial; and (3) an increase in the flexibility and availability of services would help to ensure access to essential care.

Discovery of novel antifungal (1,3)-beta-D-glucan synthase inhibitors

The increasing incidence of life-threatening fungal infections has driven the search for new, broad-spectrum fungicidal agents that can be used for treatment and prophylaxis in immunocompromised patients. Natural-product inhibitors of cell wall (1,3)-beta-D-glucan synthase such as lipopeptide pneumocandins and echinocandins as well as the glycolipid papulacandins have been evaluated as potential therapeutics for the last two decades. As a result, MK-0991 (caspofungin acetate; Cancidas), a semisynthetic analogue of pneumocandin B(o), is being developed as a broad-spectrum parenteral agent for the treatment of aspergillosis and candidiasis. This and other lipopeptide antifungal agents have limited oral bioavailability. Thus, we have sought new chemical structures with the mode of action of lipopeptide antifungal agents but with the potential for oral absorption. Results of natural-product screening by a series of newly developed methods has led to the identification of four acidic terpenoid (1,3)-beta-D-glucan synthase inhibitors. Of the four compounds, the in vitro antifungal activity of one, enfumafungin, is comparable to that of L-733560, a close analogue of MK-0991. Like the lipopeptides, enfumafungin specifically inhibits glucan synthesis in whole cells and in (1,3)-beta-D-glucan synthase assays, alters the morphologies of yeasts and molds, and produces a unique response in Saccharomyces cerevisiae strains with point mutations in FKS1, the gene which encodes the large subunit of glucan synthase.

Distribution and origin of secretoneurin-immunoreactive nerves in the female rat uterus

Secretoneurin is a 33-amino acid peptide derived from secretogranin II. Secretoneurin immunoreactivity has been localized in the peripheral nervous system where it exerts potent chemotactic activity for monocytes and may play a role in inflammation. Secretoneurin could play a role in this process, although the presence and distribution of secretoneurin-immunoreactive neurons in the female reproductive system has not been documented. Thus, this study was undertaken to examine secretoneurin immunoreactivity in nerves of the rat uterus and uterine cervix. A moderate plexus of secretoneurin-immunoreactive nerve fibers was present in the myometrium and endometrium of the uterus as well as in the smooth muscle and endocervix of the cervix. Many of these fibers were associated with the vasculature as well as the myometrium. Secretoneurin immunoreactivity was present in small- to medium-sized neurons of dorsal root and nodose ganglia. Retrograde tracing with FluoroGold indicated that some of these sensory neurons project axons to the cervix and uterine horns. Secretoneurin-immunoreactive terminal-like structures were associated with neurons in the sacral parasympathetic nucleus of the lumbosacral spinal cord. In addition, some secretoneurin terminals were apposed to pelvic parasympathetic neurons in the paracervical ganglia that projected axons to the uterus and cervix. Double-immunostaining indicated co-existence of calcitonin gene-related peptide or substance P with secretoneurin in some sensory neurons, in some terminals of the pelvic ganglia, as well as nerve fibers in the uterine horn and cervix. Finally, fibers in the uterus and cervix were depleted of secretoneurin by capsaicin treatment. This study indicates that secretoneurin is present in the uterus in C-afferent nerve fibers whose cell bodies are located in sensory ganglia. Some of these fibers contain both secretoneurin and calcitonin gene-related peptide or substance P. These substances have functions in inflammatory reactions. Further, secretoneurin could influence postganglionic parasympathetic "uterine-related" neurons in the pelvic ganglia and preganglionic parasympathetic neurons in the lumbosacral spinal cord.

The teaching and learning principles of metropolitan Aborigines with diabetes

This study was undertaken at a leading Aboriginal health agency in Adelaide called Nunkuwarrin Yunti (King & Wilson 1998). One of the aims not previously reported involved identifying the way that metropolitan Aborigines prefer to learn about their diabetes management. An ethnographic approach was used to interview ten Aboriginal health professionals and four clients (n = 14) about this topic. The results indicated the worldview held by metropolitan Aborigines about diabetes health care, the Aboriginal learner, beliefs about teaching and learning, the characteristics of an effective teacher and a suggested teaching plan.

A simple, inexpensive method for teaching how membrane potentials are generated

We have developed a simple laboratory exercise that uses an inexpensive dialysis membrane (molecular weight cutoff = 100) to illustrate the generation of membrane potentials (Vm) across plasma membranes of animal cells. A piece of membrane approximately 2.0 cm2 is mounted in an Ussing-like chamber. One chamber half is designated cytosol and the other half external. Chamber sidedness helps students relate their findings to those of real cells. As in real cells, outward directed K+ concentration gradients [high cytosolic K+ concentration ([K+]c) and low extracellular K+ concentration] generate cytosol electrically negative Vm with a slope of approximately -45 mV/decade change in [K+]c. The polarity of Vm reflects the outward flow of potassium ions because flow of the larger counterion, H2PO4-, is restricted to the pores in the membrane. A slope less than Nernstian (<59 mV/decade) suggests that the membrane is slightly permeable to H2PO4-. Importantly, this facilitates teaching the use of the Nernst equation to quantify the relationship between ion concentration ratios across membranes and magnitude of Vm. For example, students use their data and calculate a permeability ratio PK/PH2PO4 that corresponds to a slope of approximately 24% less than Nernstian. This calculation shows that Nernstian slopes are achieved only when permeability to the counterion is zero. Finally, students use the concept of membrane capacitance to calculate the number of ions that cross the membrane. They learn where these ions are located and why the bulk solutions conform to the principle of electroneutrality.

A 50 EW/cm;2 Ti:sapphire laser system for studying relativistic light-matter interactions

A 10-Hz repetition rate, 60-TW peak power, Ti:sapphire laser system was developed for use in experiments where relativistic effects dominate the physics. The temporal, spectral, energy and spatial characteristics of the laser pulses were measured in single shot format. The pulse duration ranged from 22 fs to 25 fs and the pulse energy averaged 1.3 J. Atomic photoionization measurements quantified the peak intensity of the laser pulse in situ. The measurements indicated an intensity of at least 510 19 W/cm 2 was produced.

Hepatitis C antibody detection in dried blood spots

In the UK, there have been few studies of the seroprevalence of antibodies to hepatitis C virus (anti-HCV). As part of an ongoing prevalence study of HCV in injecting drug users, we have developed a technique for detecting anti-HCV in blood spots dried on filter paper using a commercially available assay. Subjects with and without serum anti-HCV were studied. The manufacturer's recommended cut-off (CO) for a positive anti-HCV result is kit-dependent, and therefore a ratio of test result (T) to kit CO was used to standardize results. T/CO values greater than 0.99 had a sensitivity of 100% and a specificity of 87.5% for anti-HCV detection. T/CO values greater than 1.99 had a sensitivity of 97.2% and a specificity of 100%. Hence, testing dried blood spots may be useful for detecting anti-HCV in epidemiological studies and as a diagnostic test in patients with poor peripheral venous access.

Calretinin-immunoreactive nerves in the uterus, pelvic autonomic ganglia, lumbosacral dorsal root ganglia and lumbosacral spinal cord

Nerves containing the calcium-binding protein calretinin have been reported in several organs but not in female reproductive organs and associated ganglia. This study was undertaken to determine if nerves associated with the uterus contain calretinin and the source(s) of calretinin-synthesizing nerves in the rat (are they sensory, efferent, or both?). Calretinin-immunoreactive nerves were present in the uterine horns and cervix where they were associated with arteries, uterine smooth muscle, glands, and the epithelium. Calretinin-immunoreactive terminals were apposed to neurons in the paracervical ganglia; in addition, some postganglionic neurons in this ganglion were calretinin positive. Calretinin perikarya were present in the lumbosacral dorsal root ganglia, no-dose ganglia, and lumbosacral spinal cord. Retrograde axonal tracing, utilizing Fluorogold injected into the uterus or paracervical parasympathetic ganglia, revealed calretinin-positive/Fluorogold-labeled neurons in the dorsal root and nodose ganglia. Also, capsaicin treatment substantially reduced the calretinin-positive fibers in the uterus and pelvic ganglia, thus indicating the sensory nature of these fibers. The presence of calretinin immunoreactivity identifies a subset of nerves that are involved in innervation of the pelvic viscera and have origins from lumbosacral dorsal root ganglia and vagal nodose ganglia. Though the exact function of calretinin in these nerves is not currently known, calretinin is likely to play a role in calcium regulation and their function.

Modelling density-dependent resistance in insect-pathogen interactions

We consider a mathematical model for a host-pathogen interaction where the host population is split into two categories: those susceptible to disease and those resistant to disease. Since the model was motivated by studies on insect populations, we consider a discrete-time model to reflect the discrete generations which are common among insect species. Whether an individual is born susceptible or resistant to disease depends on the local population levels at the start of each generation. In particular, we are interested in the case where the fraction of resistant individuals in the population increases as the total population increases. This may be seen as a positive feedback mechanism since disease is the only population control imposed upon the system. Moreover, it reflects recent experimental observations from noctuid moth-baculovirus interactions that pathogen resistance may increase with larval density. We find that the inclusion of a resistant class can stabilise unstable host-pathogen interactions but there is greatest regulation when the fraction born resistant is density independent. Nonetheless, inclusion of density dependence can still allow intrinsically unstable host-pathogen dynamics to be stabilised provided that this effect is sufficiently small. Moreover, inclusion of density-dependent resistance to disease allows the system to give rise to bistable dynamics in which the final outcome is dictated by the initial conditions for the model system. This has implications for the management of agricultural pests using biocontrol agents-in particular, it is suggested that the propensity for density-dependent resistance be determined prior to such a biocontrol attempt in order to be sure that this will result in the prevention of pest outbreaks, rather than their facilitation. Finally we consider how the cost of resistance to disease affects model outcomes and discover that when there is no cost to resistance, the model predicts stable periodic outbreaks of the insect population. The results are interpreted ecologically and future avenues for research to address the shortfalls in the present model system are discussed.

Stability of questionnaire items in sport and exercise psychology: bootstrap limits of agreement

We describe an alternative method for assessing the stability of individual questionnaire items in sport and exercise psychology. To date, the Pearson product-moment correlation coefficient has been widely used in psychometrics. We propose an alternative non-parametric method based on proportion of agreement. Ninety-two male university students completed the revised 9-item Social Physique Anxiety Scale on two occasions, separated by a 2-week interval. Point estimates of the proportion of direct within-individual agreement between the two occasions were calculated separately for each item of the Social Physique Anxiety Scale. Estimates of uncertainty of the agreement were calculated using a bootstrapping resampling technique. For each item, 2000 bootstrap samples (each n = 92 pairs) were redrawn from the original sample. The sample statistic was calculated for each bootstrap sample to provide a bootstrap sampling distribution. The 95% confidence intervals (CI) were then calculated using the percentile method. The three most problematic items were items 7, 8 and 10 (as labelled in the original 12-item scale). These items demonstrated an agreement of 0.46 (95% CI= 0.36 0.56), 0.42 (95% CI = 0.33-0.52) and 0.41 (95% CI = 0.32-0.51) respectively. Our proposed method measures absolute agreement between test-retest responses, is free of normal assumptions, does not depend on high between-individuals variance, and can be applied successfully to individual items in the development of psychological tests.

Effect of stretching duration on active and passive range of motion in the lower extremity

OBJECTIVES

To investigate the effect of different durations of stretching (five or 15 seconds) on active and passive range of motion (ROM) in the lower extremity during a five week flexibility training programme.

METHOD

Twenty four university sport club members (19 men, five women), with a mean (SD) age of 20.5 (1.35) years, were randomly assigned to one of three groups (two treatment and one control). The two treatment groups participated in a static active stretching programme three times a week for a five week period, holding each stretch for a duration of either five or 15 seconds. The total amount of time spent in a stretched position was controlled. The five second group performed each stretch nine times and the 15 second group three times resulting in a total stretching time of 45 seconds for both groups for each exercise. The control group did not stretch. Active and passive ROM were determined during left hip flexion, left knee flexion, and left knee extension before and after the training programme using an inclinometer.

RESULTS

Two factor within subject analysis of variance indicated no significant difference in ROM before and after the training programme for the control group. However, significant improvements in active and passive ROM (p < 0.05) were shown in both treatment groups after the five week training programme. Two factor analysis of variance with repeated measures and post hoc analysis showed significant differences between the treatment groups and the control group for the improvements observed in active (p < 0.05) and passive (p < 0.05) ROM. The five and 15 second treatment groups did not differ from one another when ROM was assessed passively, but significant differences were apparent for active ROM, with the 15 second group showing significantly greater improvements (p < 0.05) than the five second group.

CONCLUSION

These findings suggest that holding stretches for 15 seconds, as opposed to five seconds, may result in greater improvements in active ROM. However, sustaining a stretch may not significantly affect the improvements gained in passive ROM.

Crystallization and preliminary diffraction data analysis of both single and pseudo-merohedrally twinned crystals of rubredoxin oxygen oxidoreductase from Desulfovibrio gigas

Crystals of rubredoxin oxygen oxidoreductase have been obtained and characterized. They belong to space group P2(1)2(1)2, with unit-cell dimensions a = 88.24 (15), b = 101.25 (7), c = 90.80 (3) A. The homodimer (86 kDa) in the asymmetric unit is related by a non-crystallographic twofold rotation axis parallel to the ab 'diagonal' direction, as shown by the self-rotation maximum in the section with chi = 180 degrees. This pseudo-crystallographic symmetry element was also found to be the twinning axis of pseudo-merohedrally twinned crystals, leading to apparent pseudo-tetragonal P42(1)2 crystal symmetry.

A clinical trial of retroviral-mediated transfer of a rev-responsive element decoy gene into CD34(+) cells from the bone marrow of human immunodeficiency virus-1-infected children

Genetic modification of hematopoietic stem cells with genes that inhibit replication of human immunodeficiency virus-1 (HIV-1) could lead to development of T lymphocytes and monocytic cells resistant to HIV-1 infection after transplantation. We performed a clinical trial to evaluate the safety and feasibility of this procedure, using bone marrow from four HIV-1-infected pediatric subjects (ages 8 to 17 years). We obtained bone marrow, isolated CD34(+) cells, performed in vitro transduction with a retroviral vector carrying a rev-responsive element (RRE) decoy gene, and reinfused the cells into these subjects with no evidence of adverse effects. The levels of gene-containing leukocytes in peripheral blood samples in the 1 year after gene transfer/cell infusion have been extremely low. These observations support the potential of performing gene therapy for HIV-1 using hematopoietic cells, but emphasize the need for improved gene transfer techniques.

Adenovirus-mediated gene transfer of the beta2-adrenergic receptor to donor hearts enhances cardiac function

Gene transfer to modify donor heart function during transplantation has significant therapeutic implications. Recent studies by our laboratory in transgenic mice have shown that overexpression of beta2-adrenergic receptors (beta2-ARs) leads to significantly enhanced cardiac function. Thus, we investigated the functional consequences of adenovirus-mediated gene transfer of the human beta2-AR in a rat heterotopic heart transplant model. Donor hearts received 1 ml of solution containing 1 x 1010 p.f.u. of adenovirus encoding the beta2-AR or an empty adenovirus as a control. Five days after transplantation, basal left ventricular (LV) pressure was measured using an isolated, isovolumic heart perfusion apparatus. A subset of hearts was stimulated with the beta2-AR agonist, zinterol. Treatment with the beta2-AR virus resulted in global myocardial gene transfer with a six-fold increase in mean beta-AR density which corresponded to a significant increase in basal contractility (LV + dP/dtmax, control: 3152.1 +/- 286 versus beta2-AR, 6250.6* +/- 432.5 mmHg/s; n = 10, *P < 0.02). beta2-AR overexpressing hearts also had higher contractility after zinterol administration compared with control hearts. Our results indicate that myocardial function of the transplanted heart can be enhanced by the adenovirus-mediated delivery of beta2-ARs. Thus, genetic manipulation may offer a novel therapeutic strategy to improve donor heart function in the post- operative setting.

Heritable variation in resistance to gastro-intestinal nematodes in an unmanaged mammal population

The impact of parasites on natural populations has received considerable attention from evolutionary biologists in recent years. Central to a number of theoretical developments during this period is the assumption of additive genetic variation in resistance to parasites. However, very few studies have estimated the heritability of parasite resistance under field conditions, and those that have are mainly restricted to birds and their ectoparasites. In this paper, to our knowledge, we show for the first time in a free-ranging mammal population, Soay sheep (Ovis aries) living on the islands of St Kilda, that there is significant heritable variation in resistance to gastrointestinal nematodes. This result is consistent with earlier studies on this population which have indicated locus-specific associations with parasite resistance. We discuss our results in the context of current studies examining heritable resistance to parasites in domestic sheep and the possible mechanisms of selective maintenance of genetic variation for resistance to gastrointestinal nematodes in the St Kilda Soay sheep population.

Information system for clinical resource management in a regional setting

The Hospital District of Varsinais-Suomi consists of five hospitals for non-psychiatric diseases to deliver specialised health care for the population of 440,000 inhabitants in South-western Finland. We have applied an open regional information system to aid clinical resource management in such a complex expert organisation. The main areas of application have been assessment of inpatient care usage in different communities and in different diagnosis-related-groups (DRG), measurement of length of hospital stay in different DRGs and comparison of DRG unit weight costs of different hospitals. The open structure of the data base and its distribution to all parties of health care professionals has resulted in mutual decisions on structural changes and increased cost containment activities.

Comparing pediatric intentional injury surveillance data with data from publicly available sources: consequences for a public health response to violence

OBJECTIVE

A hospital based intentional injury surveillance system for youth (aged 3-18) was compared with other publicly available sources of information on youth violence. The comparison addressed whether locally conducted surveillance provides data that are sufficiently more complete, detailed, and timely that clinicians and public health practitioners interested in youth violence prevention would find surveillance worth conducting.

SETTING

The Boston Emergency Department Surveillance (BEDS) project was conducted at Boston Medical Center and the Children's Hospital, Boston.

METHOD

MEDLINE and other databases were searched for data sources that report separate data for youth and data on intentional injury. Sources that met these criteria (one national and three local) were then compared with BEDS data. Comparisons were made in the following categories: age, gender, victim-offender relationship, injury circumstance, geographic location, weapon rates, and violent injury rates.

RESULTS

Of 14 sources dealing with violence, only four met inclusion criteria. Each source provided useful breakdowns for age and gender; however, only the BEDS data were able to demonstrate that 32.6% of intentional injuries occurred among youth aged 12 and under. Comparison data sources provided less detail regarding the victim-offender relationship, injury circumstance, and weapon use. Comparison of violent injury rates showed the difficulties for practitioners estimating intentional injury from sources based on arrest data, crime victim data, or weapon related injury.

CONCLUSIONS

Comparison suggests that surveillance is more complete, detailed, and timely than publicly available sources of data. Clinicians and public health practitioners should consider developing similar systems.