Improving accuracy of quantifying nitrate removal performance and enhancing understanding of processes in woodchip bioreactors using high-frequency data

Woodchip bioreactors have gained popularity in many countries as a conservation practice for reducing nitrate load to freshwater. However, current methods for assessing their performance may be inadequate when nitrate removal rates (RR) are determined from low-frequency (e.g., weekly) concurrent sampling at the inlet and outlet. We hypothesised that high-frequency monitoring data at multiple locations can help improve the accuracy of quantifying nitrate removal performance, enhance the understanding of processes occurring within a bioreactor, and therefore improve the design practice for bioreactors. Accordingly, the objectives of this study were to compare RRs calculated using high- and low-frequency sampling and assess the spatiotemporal variability of the nitrate removal within a bioreactor to unravel the processes occurring within a bioreactor. For two drainage seasons, we monitored nitrate concentrations at 21 locations on an hourly or two-hourly basis within a pilot-scale woodchip bioreactor in Tatuanui, New Zealand. A novel method was developed to account for the variable lag time between entry and exit of a parcel of sampled drainage water. Our results showed that this method not only enabled lag time to be accounted for but also helped quantify volumetric inefficiencies (e.g., dead zone) within the bioreactor. The average RR calculated using this method was significantly higher than the average RR calculated using conventional low-frequency methods. The average RRs of each of the quarter sections within the bioreactor were found to be different. 1-D transport modelling confirmed the effect of nitrate loading on the removal process as nitrate reduction followed Michaelis-Menten (MM) kinetics. These results demonstrate that high-frequency temporal and spatial monitoring of nitrate concentrations in the field allows improved description of bioreactor performance and better understanding of processes occurring within woodchip bioreactors. Thus, insights gained from this study can be used to optimise the design of future field bioreactors.

The Effect of Frailty on Walking Recovery After Hip Fracture: A Secondary Analysis of the Community Ambulation Project

BACKGROUND

The impact of frailty on walking recovery after hip fracture has not been reported. We describe the prevalence of frailty approximately 3 months after hip fracture, and identify the impact of baseline frailty on ambulation recovery.

METHODS

Data from the Community Ambulation Project, that examined the effects of 2 multicomponent home exercise programs on 6-minute walk test in participants post hip fracture, were used to reconstruct the 5-item frailty phenotype. We detailed the prevalence of frailty by subgroup and assessed the comparability between frailty groups for the categorical variable of achieving 300 m in 6-minute walk test (community ambulation threshold), and the continuous variable of total distance in 6-minute walk test before and after 16 weeks of intervention.

RESULTS

Of the 210 participants, 9% were nonfrail, 59% were prefrail, and 32% were frail. The odds of a nonfrail participant achieving the 300-m threshold were 14.4 (95% CI: 2.4-87.6) times the odds of a frail participant, while a prefrail participant's odds were 6.1 (95% CI: 1.3-28.4) times after controlling for treatment group and baseline walking distance. The nonfrail participants had an increase of 92.1 m from baseline to 16 weeks, the prefrail had a 50.8 m increase, and the frail group had the smallest increase of 36.6 m (p < .001 for all).

CONCLUSIONS

Prefrailty and frailty were highly prevalent in this sample of community-dwelling survivors of a recent hip fracture. Gains in walking distance and attaining a level of community ambulation were affected significantly by the level of baseline frailty.

Left atrial scar burden in sinus rhythm differs from atrial fibrillation using automated voltage analysis during radiofrequency ablation for atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Introduction

Scar burden in atrial fibrillation (AF) can be overestimated due to many factors. Scar burden has prognostic value and substrates considered for ablation by some electrophysiologists. We compared left atrial (LA) scar voltage in AF to sinus rhythm (SR) using voltage histogram analysis (VHA) of those undergoing pulmonary vein isolation (PVI) for persistent AF (PeAF). We believe this is the first study analysing LA scar location in SR and AF using VHA.

Methods

We retrospectively analysed 120 anatomical segments (AS) and whole LA voltages (N= 10 patients, mean age 68 ± 7, 4 females) in SR and AF. Fast anatomical maps (FAM) were grouped into 6 AS in AF and SR: Anterior, Posterior, Roof, Floor, Septal and Lateral AS, which were analysed via VHA (Figure 1) in 10 voltage ranges between 0mV-0.5mV. Total LA area in each voltage aliquot was recorded in SR and AF, taking diseased LA as 0.2-0.5mV and dense LA scar as &lt;0.2mV. The pulmonary veins, mitral annulus and trans-septal puncture sites were excluded from analyses. We included patients over age 18 with PeAF who had de novo PVI with no extra ablation lines, maps with &gt;1000 voltage points in both rhythms and uniform procedure involving initial mapping in AF then remapping in SR after PVI. Statistical analyses conducted with IBM SPSS v.26.

Results

Total LA scar burden was greater in AF (Mean 142.76 mm², SD ± 138.78mm²) than SR (Mean 109mm², SD ± 107.8mm²), p= &lt;0.0001, Table 1. Scar correlation in SR and AF had a good relationship, R = 0.416 (p= &lt;0.001). Every 1mm² of scar identified during SR yielded a mean of 1.54mm² in AF, (p= &lt;0.001).

Conclusions

AF was associated with higher scar burden in the Roof, Anterior, Lateral and Posterior AS. Dense LA scar (≤ 0.2mV) on the Posterior AS was significantly higher in AF, while in other AS was comparable to SR. Mapping substrate in AF, especially the posterior wall, may be misleading as scar burden may be overestimated when compared to SR. Table 1Voltage&lt; 0.02 mV (mean area ± SD mm2)0.2-0.5mV (mean area mm2)RhythmSRAFp-valueSRAFp-valueEntire LA115.89 ± 113.61143.41 ± 144.230.02*105.78 ± 103.73144.00 ± 135.24&lt;0.0001*Roof82.72 ± 117.3283.68 ± 113.560.95115 ± 77.14150.61 ± 93.170.01*Anterior131.8 ± 169.53126.5 ± 154.570.85158.53 ± 99.22220.87 ± 173.070.002*Lateral70.5 ± 80.0090.57 ± 117.990.3687.52 ± 66.82137.05 ± 104.990.0002*Septal80.99 ± 89.0380.99 ± 89.030.6899.123 ± 73.62115.37 ± 84.830.18Floor105.1 ± 134.91106.42 ± 148.670.96117.62 ± 85.41151.2 ± 110.070.052Posterior102.14 ± 157.47159.03 ± 194.650.02*138.27 ± 112.28234 ± 150.45&lt;0.0001*LA scar distribution in SR and AF, *denotes significant results.Abstract Figure 1

Ethical challenges experienced by researchers in community-based participatory research

Background

Political, economic and climate events continue to bring the dismantling of communities and creation of new ones. Understanding successful models of adaptation and working with communities to address their health and wellbeing needs requires ethically sound public health research. Community-Based Participatory Research (CBPR) has been proposed as an equitable, empowering partnership approach to collaborative health research that encapsulates analysis, advocacy and action for the future wellbeing of communities. Meanwhile, a strong interest in ethical implications of CBPR continues in international literature, yet with a notable lack of research that captures the experience of researchers who had ethical challenges in their CBPR studies. The aim of this research was to address this lack of evidence by exploring those experiences of CBPR researchers internationally.

Methods

An innovative data collection method was designed utilising a purpose-built blog. This internet-based, qualitative online study enabled asynchronous international data collection on the blog. Participants were researchers with experience of CBPR and were recruited through social media platforms. Blog narratives of first-hand experiences of CBPR researchers were analysed using thematic analysis.

Results

The themes that emerged from blog data analysis were researchers' challenges with balancing participant protection and autonomy, dealing with partnership tensions, and the enduring impacts on the researchers.

Conclusions

This study enhances our understanding of ethical challenges in CBPR with evidence of enduring impacts on researchers of the 'tightrope' they walked in the interests of maintaining research integrity and ethical responsibility towards their partnering communities. Challenges arose largely from complexities of CBPR coupled with rigid regulatory structures of human research ethics review that struggles to respond adequately in the interests of communities and researchers.

Key messages

At this critical time for the future of humanity, communities can benefit from CBPR. A positive way forward for ethical review of CBPR exists for those with power to make a difference.

Exercise for Smoking Cessation in Postmenopausal Women: A Randomized, Controlled Trial

BACKGROUND

Postmenopausal smokers have difficulty quitting smoking and experience considerable weight gain with smoking cessation. We examined whether adjunctive smoking treatment with exercise, compared to a relaxation control condition, could improve cigarette abstinence, decrease cigarettes smoked per day (CPD), and ameliorate changes in body mass index (BMI) in postmenopausal smokers.

METHODS

Women (N = 301) signed informed consent and were randomized to treatment at two sites (Universities of Connecticut and Minnesota). We randomized groups of participants to a comprehensive group treatment program that included 12 weeks of varenicline and either a moderate exercise or relaxation component for 6 months. Participants were followed for a year after medication treatment.

RESULTS

Overall, 17.3% of patients reported carbon monoxide-verified continuous abstinence for the 9- to 12-week period, and 11.6% reported prolonged abstinence at 1 year, with no significant differences between treatment conditions. CPD reported at study visits showed significant main effects for time in weeks, for site, and for treatment. The Exercise condition reported smoking fewer CPD over time, and that advantage widened over time. In terms of BMI, significant effects for time in weeks, and for the interaction of Week × Treatment condition, reflected gradually increasing BMI in these women over time, but with the increase in BMI slower in the Exercise condition.

CONCLUSIONS

Exercise, compared to relaxation, was associated with a reduced BMI and CPD in postmenopausal women, but did not increase end of treatment or prolonged abstinence. Further research is needed to devise exercise programs that increase smoking cessation rates in postmenopausal women.

IMPLICATIONS

This study adds to the literature on the effectiveness of a moderate exercise intervention compared to a relaxation control condition as an adjunctive treatment for smoking cessation in postmenopausal women. Our exercise program did not increase end of treatment or prolonged abstinence rates in postmenopausal women; however, there was a beneficial effect on smoking reduction and reduced body mass index. Additional research is needed to devise exercise programs that increase smoking cessation rates in postmenopausal women.

Supervised toothbrushing programs in primary schools and early childhood settings: A scoping review

OBJECTIVE

In this article we report the findings of a scoping review that aimed to identify and summarise the range of programs and guidelines available for toothbrushing programs in schools and early childhood settings. Dental caries is one of the most common preventable diseases affecting children worldwide. Untreated caries can impact on child health and wellbeing, development, socialisation and school attendance. Supervised toothbrushing programs in schools and other early childhood settings can be effective in improving the oral health of young children. There is limited understanding of the salient issues to consider when developing such programs or how they are best implemented in real world settings.

METHODS

A scoping review methodology was utilised to provide a summary of the guidelines and programs available. Key search terms were developed, mapped and utilised to identify guidelines and programs across 6 databases and key search engines.

RESULTS

We located 26 programs and guidelines that met the inclusion and exclusion criteria for the review. These were collated and summarised across key countries and critical aspects of program development and implementation were identified. Toothbrush type and storage, toothpaste strength and method of dispensing, toothbrush storage, staff training and parental consent are key considerations that varied widely.

CONCLUSIONS AND RECOMMENDATIONS

Guidelines for supervised toothbrushing programs vary within and across countries due to differences in water fluoridation and availability of low fluoride toothpastes. The results of this review provide critical information to be considered when establishing and implementing toothbrushing programs in these settings.

Circulating levels of endocannabinoids and oxylipins altered by dietary lipids in older women are likely associated with previously identified gene targets

Postmenopausal women (PMW) report marginal n-3 PUFA intakes and are at risk of chronic diseases associated with the skeletal, muscular, neuroendocrine, and cardiovascular systems. How n-3 PUFA affect the amounts of endocannabinoids (ECs) and oxylipins (OLs) of metabolic and physiologic importance in PMW is not clear. Based on our recent findings that dietary n-3 PUFA alter gene targets of the EC system and lower pro-inflammatory OL we proceeded to characterize these actions in blood of PMW. Our aim was to determine levels of the ECs, OLs, and global metabolites (GM) in white PMW (75±7y), randomized in a double-masked manner, from baseline to 6mo after receiving a fish oil supplement of n-3 PUFA (720mg 20:5n3+480mg 22:6n3/d, n=20) or placebo (1.8g oleic acid/d, n=20). ECs and OLs in serum were determined by UPLC-MS/MS and GM by GC-MS and LC-MS/MS. Plasma 20:5n3 and 22:6n3 levels increased in PMW given fish oil. EC n-6 acyl-ethanolamides, arachidonate-derived diols were decreased and 20:5n3 and 22:6n3 diols, epoxides, and alcohols were increased in PMW given fish oil. GM analysis revealed that n-3 PUFA supplementation increased renal steroid hormone and proteolytic metabolite levels in PMW. Herein, we confirm that gene targets of the EC system, previously found as modifiable by n-3 PUFA result in changes in the levels of ECs and OLs in PMW. This study shows phenotypic responses (in levels) to n-3 PUFA supplementation in PMW and increases of n-3 acyl-ethanolamide and n-3-derived OL of clinical considerations in aging.

The Effect of the Traditional Mediterranean-Style Diet on Metabolic Risk Factors: A Meta-Analysis

The Mediterranean-style diet (MedSD) has gained attention for its positive effects on health outcomes, including metabolic risk factors. However, it is unknown as to which components of MedSD interventions are most beneficial in reducing risk. The objective of this meta-analysis was to obtain effect sizes for metabolic risk factors and explain the variability across the current literature based on study design, sample, and diet characteristics. Six electronic databases were searched from inception until 9 February 2016. Data from 29 studies (N = 4133) were included. There were significant effects in favor of the MedSD for waist circumference, triglycerides, blood glucose, systolic blood pressure, and diastolic blood pressure (d+ = -0.54; d+ = -0.46; d+ = -0.50; d+ = -0.72; d+ = -0.94, respectively). The MedSD was significantly beneficial when the intervention was longer in duration, was conducted in Europe, used a behavioral technique, and was conducted using small groups. The traditional MedSD had significant beneficial effects on five of the six metabolic risk factors. Results from this study provide support for population specific dietary guideline for metabolic risk reduction.

Methodologic quality of meta-analyses and systematic reviews on the Mediterranean diet and cardiovascular disease outcomes: a review

BACKGROUND

Several systematic reviews/meta-analyses published within the past 10 y have examined the associations of Mediterranean-style diets (MedSDs) on cardiovascular disease (CVD) risk. However, these reviews have not been evaluated for satisfying contemporary methodologic quality standards.

OBJECTIVE

This study evaluated the quality of recent systematic reviews/meta-analyses on MedSD and CVD risk outcomes by using an established methodologic quality scale. The relation between review quality and impact per publication value of the journal in which the article had been published was also evaluated.

DESIGN

To assess compliance with current standards, we applied a modified version of the Assessment of Multiple Systematic Reviews (AMSTARMedSD) quality scale to systematic reviews/meta-analyses retrieved from electronic databases that had met our selection criteria: 1) used systematic or meta-analytic procedures to review the literature, 2) examined MedSD trials, and 3) had MedSD interventions independently or combined with other interventions.

RESULTS

Reviews completely satisfied from 8% to 75% of the AMSTARMedSD items (mean ± SD: 31.2% ± 19.4%), with those published in higher-impact journals having greater quality scores. At a minimum, 60% of the 24 reviews did not disclose full search details or apply appropriate statistical methods to combine study findings. Only 5 of the reviews included participant or study characteristics in their analyses, and none evaluated MedSD diet characteristics.

CONCLUSIONS

These data suggest that current meta-analyses/systematic reviews evaluating the effect of MedSD on CVD risk do not fully comply with contemporary methodologic quality standards. As a result, there are more research questions to answer to enhance our understanding of how MedSD affects CVD risk or how these effects may be modified by the participant or MedSD characteristics. To clarify the associations between MedSD and CVD risk, future meta-analyses and systematic reviews should not only follow methodologic quality standards but also include more statistical modeling results when data allow.

An exploration of strategies used by older people to obtain information about health- and social care services in the community

PURPOSE

To explore the strategies used by older people living in Ireland to obtain information about community health and social services.

METHODS

A qualitative exploratory design was used. Focus groups (n = 3) were conducted with community dwelling older people (n = 17). A series of vignettes were used to guide discussion regarding hypothetical situations that approximated real-life scenarios for older people. Data were transcribed verbatim and analysed using content analysis.

RESULTS

Obtaining information about community health and social services is an ongoing process that requires continuous commitment by older adults. Key strategies which emerged from the data included (i) taking a proactive stance towards accessing health information, (ii) making use of personal networks in your community and (iii) developing 'insider' knowledge.

CONCLUSION

Older people in this study had a proactive approach to obtaining health information and identified the importance of taking responsibility for managing their own needs. Despite this, obtaining basic information about community health and social services was a challenging and time-consuming process. Future research should focus on developing health literacy interventions that build upon and expand the strategies currently used by older people.

Returning home: psychosocial care during the re-entry phase of cancer survivorship in rural Australia

The purpose of this research was to highlight gaps in formal psychosocial care for cancer survivors in rural communities. The study was conducted in rural Victoria, Australia, and involved interviews with people with various stages of cancer progression, cancer diagnoses and survival times, who were interviewed about their experiences of psychosocial cancer care. Interviews focused on their experience of psychosocial care and were audio-recorded and transcribed verbatim. Data were thematically analysed to identify key themes. Findings demonstrate that psychosocial care is essentially informal within the re-entry period after cancer diagnosis and treatment. Despite current Australian clinical guidelines on psychosocial care for people with cancer, which indicate the need for the provision of formal psychosocial care, participants in this study largely cared for themselves, or received informal support from family, friends and community members. Many psychosocial needs remained unmet and professional support was lacking. While this study was conducted in rural Australia, many of our findings have been echoed in studies from other countries. The findings have implications for treatment protocols and discharge planning, health professional-patient-family relationships, and the long-term well-being of cancer survivors living in rural communities. A model for understanding the experience of formal supportive care during the re-entry phase of survivorship is proposed.

An evidence-based comparison of operational criteria for the presence of sarcopenia

Background.

Several consensus groups have previously published operational criteria for sarcopenia, incorporating lean mass with strength and/or physical performance. The purpose of this manuscript is to describe the prevalence, agreement, and discrepancies between the Foundation for the National Institutes of Health (FNIH) criteria with other operational definitions for sarcopenia.

Methods.

The FNIH Sarcopenia Project used data from nine studies including: Age, Gene and Environment Susceptibility-Reykjavik Study; Boston Puerto Rican Health Study; a series of six clinical trials from the University of Connecticut; Framingham Heart Study; Health, Aging, and Body Composition Study; Invecchiare in Chianti; Osteoporotic Fractures in Men Study; Rancho Bernardo Study; and Study of Osteoporotic Fractures. Participants included in these analyses were aged 65 and older and had measures of body mass index, appendicular lean mass, grip strength, and gait speed.

Results.

The prevalence of sarcopenia and agreement proportions was higher in women than men. The lowest prevalence was observed with the FNIH criteria (1.3% men and 2.3% women) compared with the International Working Group and the European Working Group for Sarcopenia in Older Persons (5.1% and 5.3% in men and 11.8% and 13.3% in women, respectively). The positive percent agreements between the FNIH criteria and other criteria were low, ranging from 7% to 32% in men and 5% to 19% in women. However, the negative percent agreement were high (all >95%).

Conclusions.

The FNIH criteria result in a more conservative operational definition of sarcopenia, and the prevalence was lower compared with other proposed criteria. Agreement for diagnosing sarcopenia was low, but agreement for ruling out sarcopenia was very high. Consensus on the operational criteria for the diagnosis of sarcopenia is much needed to characterize populations for study and to identify adults for treatment.

Evidence for low androgenicity among Indian (South Asian) men

There are increasing data indicating profound ethnic differences in the levels of virilization of males. It is well understood that the intensity of testosterone-mediated effects is modulated by sex hormone binding globulin (SHBG) and the CAG repeat lengths in the androgen receptor (AR) gene. We determined the serum testosterone, estradiol and SHBG levels and average CAG repeat lengths among a group of healthy older Indian men living in Connecticut, USA and compared these parameters with those of a reference group of white Caucasian men. We also compared various parameters that represent the end-manifestations of testosterone activity - serum prostate-specific antigen (PSA) levels, lean body mass, skeletal mineralization and visceral fat. Our data suggest that men from the Indian subcontinent are smaller, manifest lower levels of circulating free testosterone, lower mean PSA levels and lean body mass, but are comparable to white Caucasian men in terms of SHBG, estradiol, levels of visceral fat and CAG repeat length. These data suggest that Indian men manifest a lower level of virilization compared to white Caucasian males and that this might be due to lower mean circulating testosterone levels rather than higher AR CAG repeat length or SHBG.

Reference values for physical performance measures in the aging working population

OBJECTIVE

The aim of this study was to determine reference physical performance values in older aging workers.

BACKGROUND

Cross-sectional physical performance measures were collected for 736 manufacturing workers to assess effects of work and nonwork factors on age-related changes in musculoskeletal function and health.

METHOD

Participants underwent surveys and physical testing that included bioelectrical impedance analysis, range-of-motion measures, exercise testing, and dynamic assessment.

RESULTS

Physical characteristics, such as blood pressure and body fat percentage, were comparable to published values. Dynamic and range-of-motion measurements differed from published normative results. Women had age-related decreases in cervical extension and lateral rotation. Older men had better spinal flexion than expected. Predicted age-related decline in lower-extremity strength and shoulder strength in women was not seen. Men declined in handgrip, lower-extremity strength, and knee extension strength, but not trunk strength, across age groups. There was no appreciable decline in muscle fatigue at the trunk, shoulder, and knee with aging for either gender, except for the youngest age group of women.

CONCLUSION

Normative values may underestimate physical performance in "healthy" older workers, thereby underappreciating declines in less healthy older workers. Work may be preservative of function for a large group of selected individuals. A "healthy worker effect" may be greater for musculoskeletal disease and function than for heart disease and mortality.

APPLICATION

Clinicians and researchers studying musculoskeletal function in older workers can use a more specific set of reference values.

Weaning onto solid foods: some of the challenges

Weaning--the transition from milk to solid food--influences life-long health. Dietary challenges during weaning include providing sufficient critical nutrients such as iron with minimal added sugar and fat and no added salt. This study assessed the inclusion of iron-containing red meat in infant diets before age one year, and the Irish commercial baby food environment. Of mothers with an infant under 30 months of age who were surveyed in shopping centres in Ireland (n195), 82% (n159) reported wanting more weaning information. A quarter (n24) of infants over age 12 months (n97) received no iron-containing red meat before age one year. A scan of commercial baby foods in Ireland identified 448 products. While all complied with baby food legislation, 15% (n69) were intrinsically high in sugar and fat, or contained added salt. This study indicates the need for specific guidance on best infant feeding practice in Ireland.

Towards the development of integrated epilepsy services: an audit of documented epilepsy care

Effective chronic disease management (CDM) requires the ready availability and communication of accurate, clinical disease specific information. Using epilepsy as a probe into CDM, we report on the availability and reliability of clinical information in the primary care records of people with epilepsy (PWE). The medical records of 374 PWE from 53 general practices in the Mid-West region of Ireland were examined. Confirmation of an epilepsy diagnosis by a neurologist was documented for 132 (35%) patients. 282 (75%) patients had no documented evidence of receiving specialist neurology review while 149 (40%) had not been reviewed by their GP in the previous two years for their epilepsy. Significant variation in documentation of epilepsy specific information together with an inadequacy and inconsistency of existing epilepsy services was highlighted.

The 6-minute walk is associated with frailty and predicts mortality in older adults with heart failure

Heart failure (HF) may contribute to the development of functional decline and frailty in older adults. Sixty HF patients with an ejection fraction ≤ 40% evaluated in 2004 and 2005 were reevaluated in 2008. Six-minute walk distance (6MW), frailty score, and biomarkers (25-hydroxyvitamin D, C-reactive protein, and interleukin-6 [IL-6]) were measured. Participants were categorized at baseline and follow-up into 3 groups: nonfrail/normal endurance (NF/NE), nonfrail/low endurance (NF/LE) and frail/low endurance (F/LE). Survival time was assessed according to frailty/endurance status and associated predictors of mortality. Forty-three men, 17 women (mean age, 78 ± 12 years) were contacted. At follow-up, 20 had died, 20 participated, and 20 did not participate. There were no changes in frailty/endurance status over time (McNemar;P=.19). Deaths occurred in 18% of NF/NE, 45% of NF/LE, and 60% of F/LE persons. The NF/NE group had greater survival rates than the NF/LE (  P=.032) and F/LE (  P=.014) groups. The 6MW and frailty score were independently predictive of mortality, with hazard ratios of 0.82 (95% confidence interval, 0.72-0.94) and 1.64 (95% confidence interval, 1.19-2.26), respectively, as was New York Heart Association class and IL-6. Backward stepwise Cox regression revealed that 6MW and frailty each were associated with mortality (P=.005) and highly correlated. Physical function is an important predictor of mortality in older adults with HF. The 6MW may be useful as a measure of frailty.

Polymorphisms in the macrophage migration inhibitory factor gene and bone loss in postmenopausal women

Osteoporosis is a severe condition in postmenopausal women and a common cause of fracture. Osteoporosis is a complex disease with a strong genetic impact, but susceptibility is determined by many genes with modest effects and environmental factors. Only a handful of genes consistently associated with osteoporosis have been identified so far. Inflammation affects bone metabolism by interfering with the interplay between bone resorption and formation, and many inflammatory mediators are involved in natural bone remodeling. The cytokine macrophage migration inhibitory factor (MIF) has been shown to affect bone density in rodents, and polymorphisms in the human MIF promoter are associated with inflammatory disorders such as rheumatoid arthritis. We investigated the association of polymorphisms in the MIF gene with bone mineral density (BMD) and bone loss in 1002 elderly women using MIF promoter polymorphisms MIF-CATT(5-8) and rs755622(G/C) located -794 and -173 bp upstream of the transcriptional start site. Bone loss was estimated both by the change in BMD over 5 years and by the levels of bone resorption markers in serum measured at four occasions during a 5-year period. The MIF-CATT(7)/rs755622(C) haplotype was associated with increased rate of bone loss during 5 years at the femoral neck (p<0.05) and total hip (p<0.05). In addition, the MIF-CATT(7)/rs755622(C) haplotype carriers had higher levels of the bone turnover marker serum C-terminal cross-linking telopeptide of type I collagen (S-CTX-I, p<0.01) during the 5 year follow-up period. There was no association between MIF-CATT(7)/rs755622(C) and baseline BMD at femoral neck, total hip or lumbar spine. We conclude that MIF promoter polymorphisms have modest effects on bone remodeling and are associated with the rate of bone loss in elderly women.

The role of fish oil in hypertension

Essential fatty acids have been hypothesized as important to health, including cardiovascular health, for several decades. These hypotheses have been supported by epidemiologic studies. There have been several trials evaluating the effects of fish oil (omega-3 fatty acid, one of the major essential fatty acids) on hypertension in individuals with hypertension, and those without hypertension or hypercholesterolemia. The overall effect of fish oil has been a small but significant decline in blood pressure, especially in those with hypertension or hypercholesterolemia. Few side effects are reported with fish oil and all are dose dependent; side effects include gastrointestinal upset, fishy aftertaste and, uncommonly, clinical bleeding. Information on the use of omega-3 fatty acids in hypertension requires further study to understand better the appropriate dose and its benefits, specifically with aging. Preliminary data hold promise that small but significant diminution in blood pressure can be attained.

Home-based resistance training improves femoral bone mineral density in women on hormone therapy

This study tested whether moderate resistance training would improve femoral bone mineral density (BMD) in long-term users of hormone therapy with low BMD. The study was a 2-year randomized, controlled, trial (RCT) of moderate resistance training of either the lower extremity or the upper extremity. Eighty-five women participated in a 6-month observation period. The setting was center-based and home-based training. The participants were 189 women aged 59-78 years, with total femur T-scores from -0.8 to -2.8 and on hormone therapy (HT) for a minimum of 2 years (mean 11.8 years); 153 completed the trial. Lower extremity training used weight belts (mean 7.8 kg) in step-ups and chair rises; upper extremity training used elastic bands and dumbbells. Measurements were BMD and body composition [dual-energy X-ray absorptiometry (DXA)], bone turnover markers. Total femoral BMD showed a downward trend during the observation period: 0.35%+/-0.18% (P=0.14). The response to training was similar in the upper and lower groups in the primary outcomes. At 2 years, total femoral BMD increased 1.5% (95% CI 0.8%-2.2%) in the lower group and 1.8% (95% CI 1.1%-2.5%) in the upper group. Trochanter BMD increased 2.4% (95% CI 1.3%-3.5%) in the lower group and 2.5% (95% CI 1.4%-3.6%) in the upper group (for both analyses time effect P<0.001). At 1 year, a bone resorption marker (C-telopeptide) decreased 9% (P=0.04). Bone formation markers, bone-specific alkaline phosphatase, decreased 5% (P<0.001), and N-terminal type I procollagen peptide decreased 7% (P=0.01). Body composition (percent lean and percent body fat) was maintained in both groups. We concluded that long-term moderate resistance training reversed bone loss, decreased bone turnover, increased femur BMD, and maintained body composition. The similarity of response in upper and lower groups supports a systemic response rather than a site-specific response to moderate resistance training.

Detection of myocardial viability by dobutamine stress echocardiography: incremental value of diastolic wall thickness measurement

OBJECTIVE

To assess the diagnostic accuracy of baseline diastolic wall thickness (DWT) alone and as an adjunct to dobutamine stress echocardiography (DSE) for prediction of myocardial viability in patients with ischaemic left ventricular (LV) dysfunction, with the recovery of resting function after revascularisation as the yardstick.

PATIENTS

24 patients with ischaemic LV dysfunction (ejection fraction < 40%) scheduled for surgical revascularisation.

SETTING

Regional cardiothoracic centre.

METHODS

All patients underwent DSE before and resting echocardiography six months after revascularisation. DWT was measured in each of the 16 LV segments. A receiver operating characteristic (ROC) and a multi-ROC curve were generated to assess the ability of DWT alone and in combination with DSE to predict myocardial viability.

RESULTS

DWT > 0.6 cm provided a sensitivity of 80%, a specificity of 51%, and a negative predictive value of 80% for the prediction of viability in akinetic segments. DSE had an excellent specificity (92%) but a modest sensitivity (60%) in akinetic segments. A combination of improvement at DSE or DWT > 0.8 cm improved sensitivity (90% v 60%, p < 0.001) and negative predictive value (92% v 78%, p = 0.03) in akinetic segments compared with DSE alone. This was achieved with some loss in specificity (75% v 92%, p = 0.01) and positive predictive value (71% v 82%, p = 0.79).

CONCLUSIONS

DWT measurement may improve the sensitivity of DSE for the detection of myocardial viability. Akinetic segments with DWT > 0.8 cm have a good chance of recovery despite the absence of contractile reserve during DSE. Further testing may be required before excluding myocardial viability in these cases.

Direct monitoring of soil and water nitrate by FTIR based FEWS or membrane systems

The development of silver halide fibers that transmit with minimal loss into the mid-IR (MIR) paved the way to their successful utilization as effective ATR (Attenuated Total Reflectance) elements, promoting the implementation of Fiberoptic Evanescent Wave Spectroscopy (FEWS) for direct monitoring of nitrate in environmental systems. Samples containing nitrate in water, soil extracts, and pastes were used for the determination of nitrate concentration with a common ATR ZnSe crystal and with silver halide fibers (FEWS). Spectra of soil pastes and suspensions and those of phosphate, carbonate, sulfate, ammonium, and soil organic constituents were collected to study possible interference with nitrate determination. The standard error of estimate (SEE) and R2 values obtained with flat fibers, using the simple single-point correlation method, were superior to those obtained for cylindrical FEWS and ZnSe ATR crystals in pure water. A significant improvement in the SEE and R2 was achieved in most soil pastes by applying the simple mode of the Cross Correlation method. Direct transmission of MIR radiation through ion-exchange membranes, partially loaded with nitrate or carbonate, was found an effective alternative for MIR-FTIR determination of these ions. Further development and modification of the FEWS devices should allow in-situ and online determination of nitrate in soil and environmental systems.