Sex differences in recovery of quality of life 12 months post-fracture in community-dwelling older adults: analyses of the Australian arm of the International Costs and Utilities Related to Osteoporotic Fractures Study (AusICUROS).

In this study of 695 Australian older adults (aged ≥50 years), we found that men and women had a similar trajectory of health-related quality of life (HRQoL) recovery following fragility fracture at any skeletal site. These results provide us with critical knowledge that improves our understanding of health outcomes post-fracture. INTRODUCTION: Mortality is higher in men than that in women following a fragility fracture, but it is unclear whether recovery of patient-reported outcomes such as health-related quality of life (HRQoL) differs between sexes. This study aimed to identify sex differences in HRQoL recovery 12 months post-fracture. METHODS: Data were from the Australian arm of the International Costs and Utilities Related to Osteoporotic Fractures Study (AusICUROS). Participants recruited to AusICUROS were adults aged ≥50 years who sustained a fragility fracture. HRQoL was measured using the EQ-5D-3L at three time-points post-fracture: within 2 weeks (including pre-fracture recall) and at 4 and 12 months. Multivariate logistic regression analyses were undertaken, adjusting for confounders including age, education, income, and healthcare utilization post-fracture. RESULTS: Overall, 695 AusICUROS participants (536 women, 77.1%) were eligible for analysis with fractures at the hip (n = 150), distal forearm (n = 261), vertebrae (n = 61), humerus (n = 52), and other skeletal sites (n = 171). At the time of fracture, men were younger, reported a higher income, and were more likely to be employed, compared with women. For all fracture sites combined, there were no differences between men and women in recovery to pre-fracture HRQoL at 12-month follow-up (adjusted OR = 1.09; 95% CI: 0.75-1.61). When stratified by fracture site, no significant sex differences were seen for hip (OR = 1.02; 95% CI: 0.42-2.52), distal forearm (OR = 1.60; 95% CI: 0.68-3.78), vertebral (OR = 2.28; 95% CI: 0.61-8.48), humeral (OR = 1.62; 95% CI: 0.16-9.99), and other fractures (OR = 1.00; 95% CI: 0.44-2.26). CONCLUSION: Community-dwelling men and women who survived the 12 months following fragility fracture had a similar trajectory of HRQoL recovery at any skeletal site.

Correction to: Impact of whole dairy matrix on musculoskeletal health and aging-current knowledge and research gaps.

The article Impact of whole dairy matrix on musculoskeletal health and aging-current knowledge and research gaps written by N.R.W. Geiker, C. Mølgaard, S. Iuliano, R. Rizzoli,Y. Manios, L.J.C. van Loon, J.-M. Lecerf, G. Moschonis, J.-Y. Reginster, I. Givens, A. Astrup.

Impact of whole dairy matrix on musculoskeletal health and aging-current knowledge and research gaps.

Dairy products are included in dietary guidelines worldwide, as milk, yoghurt, and cheese are good sources of calcium and protein, vital nutrients for bones and muscle mass maintenance. Bone growth and mineralization occur during infancy and childhood, peak bone mass being attained after early adulthood. A low peak bone mass has consequences later in life, including increased risk of osteoporosis and fractures. Currently, more than 200 million people worldwide suffer from osteoporosis, with approximately 9 million fractures yearly. This poses a tremendous economic burden on health care. Between 5% and 10% of the elderly suffer from sarcopenia, the loss of muscle mass and strength, further increasing the risk of fractures due to falls. Evidence from interventional and observational studies support that fermented dairy products in particular exert beneficial effects on bone growth and mineralization, attenuation of bone loss, and reduce fracture risk. The effect cannot be explained by single nutrients in dairy, which suggests that a combined or matrix effect may be responsible similar to the matrix effects of foods on cardiometabolic health. Recently, several plant-based beverages and products have become available and marketed as substitutes for dairy products, even though their nutrient content differs substantially from dairy. Some of these products have been fortified, in efforts to mimic the nutritional profile of milk, but it is unknown whether the additives have the same bioavailability and beneficial effect as dairy. We conclude that the dairy matrix exerts an effect on bone and muscle health that is more than the sum of its nutrients, and we suggest that whole foods, not only single nutrients, need to be assessed in future observational and intervention studies of health outcomes. Furthermore, the importance of the matrix effect on health outcomes argues in favor of making future dietary guidelines food based.

Changes in quality of life associated with fragility fractures: Australian arm of the International Cost and Utility Related to Osteoporotic Fractures Study (AusICUROS).

UNLABELLED: We investigated change in health-related quality of life due to fracture in Australian adults aged over 50 years. Fractures reduce quality of life with the loss sustained at least over 12 months. At a population level, the loss was equivalent to 65 days in full health per fracture. PURPOSE: We aimed to quantify the change in health-related quality of life (HRQoL) that occurred as a consequence of a fracture using the EQ-5D-3 L questionnaire. METHODS: Adults aged ≥50 years with a low to moderate energy fracture were recruited from eight study centres across Australia. This prospective study included an 18-month follow-up of participants recruited within 2 weeks of a fracture (hip, wrist, humerus, vertebral and ankle). Information collected at baseline and 4, 12 and 18 months included characteristics of participants such as income level, education and prior fracture status. At 12 months post-fracture, the cumulative loss of quality of life was estimated using multivariate regression analysis to identify the predictors of HRQoL loss. RESULTS: Mean HRQoL for all participants before fracture was 0.86, with wrist fracture having the highest pre-fracture HRQoL (0.90), while vertebral fracture had the lowest (0.80). HRQoL declined to 0.42 in the immediate post-fracture period. Only participants with a wrist, humerus or ankle fracture returned to their pre-fracture HRQoL after 18 months. An increased loss of HRQoL over 12 months was associated with HRQoL prior to the fracture, hospitalisation, education and fracture site. The multiple regression explained 30 % of the variation in the cumulative HRQoL loss at 12 months post-fracture for all fractures. CONCLUSION: Low to moderate energy fractures reduce HRQoL, and this loss is sustained for at least 12 months or, in the case of hip and spine fractures, at least 18 months. At a population level, this represents an average loss of 65 days in full health per fragility fracture. This significant burden reinforces the need for cost-effective fracture prevention strategies.

Transit time flow measurement in off-pump surgery: is it a functional index of the biological graft integrity?

OBJECTIVE: Transit-time flow measurement (TTFM) represents a valid tool in the assessment of the quality of the anastomosis during coronary artery bypass graft (CABG). Nevertheless, a high variability limits its standardized use, lacking univocally accepted cut-off flow values. Our study analyzes TTFM data collected from a study population that underwent off-pump CABG (OP-CABG), with the aim to differentiate into subgroups according to the presence of diabetes mellitus. PATIENTS AND METHODS: Patients referred to the Cardiovascular Unit of S. Michele Hospital (Caserta, Italy) for coronary artery disease (CAD) and underwent OP-CABG between January 2015 and December 2019 were enrolled, and intraoperative TTFMs data were recruited and evaluated. Mean graft flow (MGF) and pulsatility index (PI) values were collected and analyzed. RESULTS: The study population was composed of 342 patients who underwent OP-CABG with TTFM data regarding 824 grafts. Diabetic patients shared a higher cardiovascular risk profile. The TTFM assessment showed better results for the use of the arterial grafts in diabetic patients, especially for those insulin-dependent; conversely, venous grafts showed worse data with lower MGF and higher PI values. In particular, the anastomoses of the saphenous vein graft with marginal obtuse (MO) coronary artery showed worse MGF results in the insulin-dependent rather than normoglycemic subgroup (28.66 vs. 38.44, p=0.003). CONCLUSIONS: Diabetic patients, especially in the insulin-dependent subgroups, have demonstrated lower MGF and higher PI values collected from venous anastomoses with, conversely, inverse results from the arterial one. These results might be correlated to an altered biological adaptability caused by the effects of the diabetic endocrine disorder.

Provision of High Protein Foods Slows the Age-Related Decline in Nutritional Status in Aged Care Residents: A Cluster-Randomised Controlled Trial.

OBJECTIVES: Malnutrition, particularly protein insufficiency, is common in institutionalised older adults and increases morbidity, mortality, and costs. We aimed to determine whether 12 months supplementation using high-protein foods (milk, cheese, yoghurt) prevents malnutrition in older adults. DESIGN: Cluster randomised control study. SETTING: Sixty Australian aged care facilities. PARTICIPANTS: Older adults living in aged care homes (n=654, mean age 86.7±7.2 years, 72% females). Intervention Facilities randomly allocated to a high-protein (n=30 intervention) or regular (n=30 controls) menu. MEASUREMENTS: Nutritional status assessed using the Mini Nutrition Assessment (MNA) tool and fasting morning blood samples (n=302) assayed for haemoglobin (Hb) and albumin. Food intake was monitored 3-monthly using visual plate waste assessment. Measurements at baseline and month 12 were analysed using random effects model accounting for clustering (facility), repeated measure and confounders. RESULTS: Addition of 11g of protein as 1.5 servings of high-protein foods daily preserved nutritional status that deteriorated in controls [MNA screen (-0.68, 95%CI: -1.03, -0.32, p<0.001) and total (-0.90, 95%CI: -1.45, -0.35, p=0.001) scores], resulting in group differences in MNA screen (0.62, 95%CI: 0.17, 1.06, p=0.007) and total (0.81, 95%CI: 0.11, 1.51, p=0.023) scores and group difference in Hb (3.60g/L, 95%CI: 0.18, 7.03, p=0.039), the net result of preservation with intervention (0.19g/L, 95%CI: -2.04, 2.42, p=0.896) and a decline in controls (-3.41g/L, 95%CI: -6.01, -0.82, p=0.010). No group differences were observed for serum albumin. CONCLUSION: Consumption of high-protein foods is a pragmatic approach to maintaining nutritional status in older adults in aged-care.

Screening, Diagnosis and Management of Sarcopenia and Frailty in Hospitalized Older Adults: Recommendations from the Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR) Expert Working Group.

Sarcopenia and frailty are highly prevalent conditions in older hospitalized patients, which are associated with a myriad of adverse clinical outcomes. This paper, prepared by a multidisciplinary expert working group from the Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR), provides an up-to-date overview of current evidence and recommendations based on a narrative review of the literature for the screening, diagnosis, and management of sarcopenia and frailty in older patients within the hospital setting. It also includes suggestions on potential pathways to implement change to encourage widespread adoption of these evidence-informed recommendations within hospital settings. The expert working group concluded there was insufficient evidence to support any specific screening tool for sarcopenia and recommends an assessment of probable sarcopenia/sarcopenia using established criteria for all older (≥65 years) hospitalized patients or in younger patients with conditions (e.g., comorbidities) that may increase their risk of sarcopenia. Diagnosis of probable sarcopenia should be based on an assessment of low muscle strength (grip strength or five times sit-to-stand) with sarcopenia diagnosis including low muscle mass quantified from dual energy X-ray absorptiometry, bioelectrical impedance analysis or in the absence of diagnostic devices, calf circumference as a proxy measure. Severe sarcopenia is represented by the addition of impaired physical performance (slow gait speed). All patients with probable sarcopenia or sarcopenia should be investigated for causes (e.g., chronic/acute disease or malnutrition), and treated accordingly. For frailty, it is recommended that all hospitalized patients aged 70 years and older be screened using a validated tool [Clinical Frailty Scale (CFS), Hospital Frailty Risk Score, the FRAIL scale or the Frailty Index]. Patients screened as positive for frailty should undergo further clinical assessment using the Frailty Phenotype, Frailty Index or information collected from a Comprehensive Geriatric Assessment (CGA). All patients identified as frail should receive follow up by a health practitioner(s) for an individualized care plan. To treat older hospitalized patients with probable sarcopenia, sarcopenia, or frailty, it is recommended that a structured and supervised multi-component exercise program incorporating elements of resistance (muscle strengthening), challenging balance, and functional mobility training be prescribed as early as possible combined with nutritional support to optimize energy and protein intake and correct any deficiencies. There is insufficient evidence to recommend pharmacological agents for the treatment of sarcopenia or frailty. Finally, to facilitate integration of these recommendations into hospital settings organization-wide approaches are needed, with the Spread and Sustain framework recommended to facilitate organizational culture change, with the help of 'champions' to drive these changes. A multidisciplinary team approach incorporating awareness and education initiatives for healthcare professionals is recommended to ensure that screening, diagnosis and management approaches for sarcopenia and frailty are embedded and sustained within hospital settings. Finally, patients and caregivers' education should be integrated into the care pathway to facilitate adherence to prescribed management approaches for sarcopenia and frailty.

Effect of dietary sources of calcium and protein on hip fractures and falls in older adults in residential care: cluster randomised controlled trial.

OBJECTIVE: To assess the antifracture efficacy and safety of a nutritional intervention in institutionalised older adults replete in vitamin D but with mean intakes of 600 mg/day calcium and <1 g/kg body weight protein/day. DESIGN: Two year cluster randomised controlled trial. SETTING: 60 accredited residential aged care facilities in Australia housing predominantly ambulant residents. PARTICIPANTS: 7195 permanent residents (4920 (68%) female; mean age 86.0 (SD 8.2) years). INTERVENTION: Facilities were stratified by location and organisation, with 30 facilities randomised to provide residents with additional milk, yoghurt, and cheese that contained 562 (166) mg/day calcium and 12 (6) g/day protein achieving a total intake of 1142 (353) mg calcium/day and 69 (15) g/day protein (1.1 g/kg body weight). The 30 control facilities maintained their usual menus, with residents consuming 700 (247) mg/day calcium and 58 (14) g/day protein (0.9 g/kg body weight). MAIN OUTCOME MEASURES: Group differences in incidence of fractures, falls, and all cause mortality. RESULTS: Data from 27 intervention facilities and 29 control facilities were analysed. A total of 324 fractures (135 hip fractures), 4302 falls, and 1974 deaths were observed. The intervention was associated with risk reductions of 33% for all fractures (121 v 203; hazard ratio 0.67, 95% confidence interval 0.48 to 0.93; P=0.02), 46% for hip fractures (42 v 93; 0.54, 0.35 to 0.83; P=0.005), and 11% for falls (1879 v 2423; 0.89, 0.78 to 0.98; P=0.04). The risk reduction for hip fractures and falls achieved significance at five months (P=0.02) and three months (P=0.004), respectively. Mortality was unchanged (900 v 1074; hazard ratio 1.01, 0.43 to 3.08). CONCLUSIONS: Improving calcium and protein intakes by using dairy foods is a readily accessible intervention that reduces the risk of falls and fractures commonly occurring in aged care residents. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12613000228785.

Establishing an Operational Definition of Sarcopenia in Australia and New Zealand: Delphi Method Based Consensus Statement.

BACKGROUND: Globally there are several operational definitions for sarcopenia, complicating clinical and research applications. OBJECTIVE: The objective of the Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR) Task Force on Diagnostic Criteria for Sarcopenia was to reach consensus on the operational definition of sarcopenia for regional use by clinicians and researchers. METHOD: A four-Phase modified Delphi process was undertaken in which 24 individuals with expertise or a recognised interest in sarcopenia from different fields across Australia and New Zealand were invited to be Task Force members. An initial face-to-face meeting was held in Adelaide, South Australia, in November 2017, followed by two subsequent online Phases conducted by electronic surveys. A final Phase was used to approve the final statements. Responses were analysed using a pre-specified strategy. The level of agreement required for consensus was 80%. RESULTS: In Phase 2, 94.1% of Task Force respondents voted in favour of adopting an existing operational definition of sarcopenia. In Phase 3, 94.4% of respondents voted in favour of adopting the European Working Group on Sarcopenia in Older People (EWGSOP) definition as the operational definition for sarcopenia in Australia and New Zealand. CONCLUSION: With consensus achieved, the ANZSSFR will adopt, promote and validate the EWGSOP operational definition of sarcopenia for use by clinicians and researchers in Australia and New Zealand.

Mediterranean diet improves sexual function in women with the metabolic syndrome.

In the present study, we tested the effect of a Mediterranean-style diet on sexual function in women with the metabolic syndrome. Women were identified in our database of subjects participating in controlled trials evaluating the effect of lifestyle changes and were included if they had a diagnosis of female sexual dysfunction (FSD) associated with a diagnosis of metabolic syndrome, a complete follow-up in the study trial and an intervention focused mainly on dietary changes. Fifty-nine women met the inclusion/exclusion criteria; 31 out of them were assigned to the Mediterranean-style diet and 28 to the control diet. After 2 years, women on the Mediterranean diet consumed more fruits, vegetables, nuts, whole grain and olive oil as compared with the women on the control diet. Female sexual function index (FSFI) improved in the intervention group, from a mean basal value of 19.7+/-3.1 to a mean post-treatment value of 26.1+/-4.1 (P=0.01), and remained stable in the control group. C-reactive protein (CRP) levels were significantly reduced in the intervention group (P<0.02). No single sexual domain (desire, arousal, lubrication, orgasm, satisfaction, pain) was significantly ameliorated by the dietary treatment, suggesting that the whole female sexuality may find benefit from lifestyle changes. A Mediterranean-style diet might be effective in ameliorating sexual function in women with metabolic syndrome.

Atrial pacing for the prevention of atrial fibrillation after cardiovascular surgery.

OBJECTIVE: The purpose of this study was to determine the efficacy of atrial pacing in the prevention of atrial fibrillation following cardiovascular surgery. BACKGROUND: Although pharmacologic therapy has been used to help prevent postoperative atrial fibrillation, it suffers from limited efficacy and adverse effects. In the nonoperative setting, novel pacing strategies have been shown to reduce recurrences of atrial fibrillation and prolong arrhythmia-free periods in patients with paroxysmal atrial arrhythmias. METHODS: A total of 154 patients (115 men; mean age, 65 +/- 10 years; ejection fraction, 53 +/- 10%) undergoing cardiac surgery (coronary artery bypass surgery, 88.3%; aortic valve replacement, 4.5%; coronary bypass + aortic valve replacement, 7.1%) had right and left atrial epicardial pacing electrodes placed at the time of surgery. Patients were randomized to either no pacing, right atrial (RAP), left atrial (LAP) or biatrial pacing (BAP) for 72 h after surgery. Beta-adrenergic blocking agents were administered concurrently to all patients following surgery. RESULTS: There was a reduction in the incidence of postoperative atrial fibrillation from 37.5% in patients receiving no postoperative pacing to 17% (p < 0.005) in patients assigned to one of the three pacing strategies. The length of hospital stay was reduced by 22% from 7.8 +/- 3.7 days to 6.1 +/- 2.3 days (p = 0.003) in patients assigned to postoperative atrial pacing. The incidence of atrial fibrillation was lower in each of the paced groups (RAP, 8%; LAP, 20%; BAP, 26%) compared with patients who did not receive postoperative pacing (37.5%). CONCLUSION: Postoperative atrial pacing, in conjunction with beta-blockade, significantly reduced both the incidence of atrial fibrillation and the length of hospital stay following cardiovascular surgery. Additional studies are needed to determine the most effective anatomic pacing site.

Rapid analysis of a plasmid by hydrophobic-interaction chromatography with a non-porous resin.

A HPLC technique has been developed, based on hydrophobic-interaction Chromatography with a non-porous packing (TSKgel Butyl-NPR, Tosoh Biosep LLC), that allows separation of the open circular (nicked) and supercoiled forms of five DNA plasmids, ranging in size from 4 to 30 kilo base pairs (kb). The identity of the bands was determined through light scattering and gel electrophoresis. Several buffers, gradients, flow-rates and temperatures were evaluated in determining the optimum operating conditions for the separation. For all plasmids a reversed ammonium sulfate in phosphate buffer (pH 7.1) gradient was established. The chromatographic resolution between the supercoiled and nicked peaks was found to be a function of flow-rate and temperature. The resolution and the elution order did not vary with plasmid size, with the open-circular form always being eluted before the supercoiled form. Hydrophobic-interaction chromatography is a useful alternative to ion exchange or size exclusion for the chromatography of large plasmids, up to 30 kb.

Successful ablation of a nonreentrant dual atrioventricular nodal tachycardia.

Selective radiofrequency catheter ablation of the slow pathway of the AV node has become the treatment of choice for AV nodal reentrant tachycardia. We describe a case of a nonreentrant AV nodal tachycardia and its successful treatment by slow pathway ablation.

Meeting the nutritional needs of elderly residents in aged-care: are we doing enough?

OBJECTIVES: [corrected] Institutionalized elderly are at high risk of malnutrition, including those residing in low-level aged-care and able to self-feed. We used comprehensive dietary intake assessments to determine the nutritional adequacy of food served to residents and if food waste contributed to insufficient nutrient intakes. DESIGN: Cross sectional. SETTING: 18 low-level aged care facilities. PARTICIPANTS: 199 residents (mean age 86.7 yrs, 76% females). MEASUREMENTS: Dietary data using 3-6 day weighed food records. Foods were categorized into main food groups (grains, fruit, vegetables, meats, dairy and 'extra') and quantified based on recommended serving sizes. Chi squared test was used to determine sex differences in proportion of residents below recommended intake levels. RESULTS: Residents were provided with sufficient serves of fruit (>2) and meats (>1), but not dairy (<3), vegetables (<5) and grain foods (women only, <4), and excess serves of 'extra' foods (>2). Mean dietary intakes did not meet recommendations for calcium, zinc, magnesium, potassium, folate and dietary fibre with many residents not meeting energy and protein requirements. Sodium intake was up to 3 times higher than recommended, and sugars consumed in excess. Food waste was 0-15% and resulted in men not consuming recommended serves of grain foods. 'Extra' foods contributed substantially to energy intake but provided few of the required nutrients. CONCLUSION: Substituting some 'extra' foods for serves of dairy, vegetables and wholegrain foods would improve the nutritional quality of foods, without altering food volume, so is feasible to improve nutritional status in elderly aged-care residents.

Consuming two additional serves of dairy food a day significantly improves energy and nutrient intakes in ambulatory aged care residents: a feasibility study.

OBJECTIVES: [corrected] Low-level aged-care residents are at risk of malnutrition. Oral supplements and fortified foods used to treat malnutrition in the elderly require special preparation and administration by staff. Therefore we aimed to determine if increasing dairy food intake in residents by two serves per day would improve energy and nutrient intakes and prevent malnutrition in residents. DESIGN: Prospective intervention study. SETTING: 2 intervention and 2 control low-level aged-care facilities in Melbourne, Australia. PARTICIPANTS: 130 residents (n = 68 intervention, 78% female, mean age 86.5 years). INTERVENTION: This feasibility study was a 4-week intervention where menus were modified to include at least two additional serves of dairy food/day. Control facilities consumed from their regular menus. MEASUREMENTS: Mean macro- and micro-nutrient intakes before and after intervention and over the same time period in controls were recorded using observed intake (food served minus waste) and changes over time determined using paired t-tests. Comparison in proportion of residents meeting nutritional requirements was determined using Chi-square distribution test. RESULTS: Following intervention, daily increases in mean energy intake (900kJ, P<0.001), protein intake (+25g, P<0.0001), proportion of energy from protein (+4%, P<0.0001) and proportion of estimated energy requirements (EER) (+18%, P<0.0001) were observed, while proportion of energy from fat decreased (-3%, P<0.0001). In controls mean energy intake remained below the EER, and protein intake remained unchanged. Increases in mean daily micronutrient intakes were observed for numerous nutrients including calcium (+679mg, P<0.0001), vitamin D (+1.4µg, P<0.0001), phosphorus (+550mg, P<0.0001), and zinc (+2.8mg, P<0.0001), which remained unchanged in control residents. Calcium and zinc intakes achieved recommended intake levels on the higher dairy diet, but were below recommended levels in controls. Mean sodium intakes remained unchanged. During intervention a greater proportion of residents achieved the EER for energy and the RDI for protein and calcium compared to controls. CONCLUSION: Two additional serves of dairy food can significantly improve nutrient intake in aged-care residents and its ease of provision makes it a viable option to potentially prevent malnutrition.

Examination of the self-selected fluid intake practices by junior athletes during a simulated duathlon event.

Thirty-two elite junior athletes in two age categories, older than or equal to 15 years old (O15) (8 females and 9 males) and less than 15 years old (U15) (8 females and 7 males), performed a laboratory-based duathlon (run-ride-run). At the completion of the event, significant body mass losses were recorded for all groups. Compared with the other three groups, the O15 males lost body mass at a greater absolute rate (1.26 +/- 0.06 kg.hr-1 vs. a mean of 0.62 +/- 0.11 kg.hr-1 for the other three groups) and a greater relative rate (1.95 +/- 0.10%BM.hr-1 vs. a mean of 1.23 +/- 0.19%BM.hr-1 for the other three groups) (p < .05). No differences were observed between groups for fluid consumption. Subjects consumed more fluid (p < .05) during the cycle phase and postevent than preevent or during the run phases. Results indicated that the athletes' fluid intake practices were insufficient to maintain adequate hydration during the simulated event.

Cation-exchange high-performance liquid chromatography of recombinant adeno-associated virus type 2.

There has been much interest recently in the development of recombinant viruses as vectors for gene therapy applications. We have constructed a recombinant adeno-associated viral (AAV) vector containing the gene encoding CFTR (cystic fibrosis transmembrane chloride regulator). This vector is currently being used in clinical trials as a treatment for cystic fibrosis. In the course of scale-up and process optimization efforts, a variety of analyses have been developed to characterize yield and quality. Although these methods produce quantitative and highly reproducible results, most are very time intensive. For example, a standard bioassay requires a 72-h incubation period followed by an additional day of analysis. Other tests such as UV spectrophotometry are fast, but unable to distinguish between whole virus, free protein, and DNA. Here, we describe an analytical cation-exchange high-performance liquid chromatographic method utilizing a TSKgel SP-NPR strong cation-exchange column. Unlike the bioassay which requires a 96-h wait for information, this method yields data in less than 20 min. In addition to the quick assay turn-around, the material eluting in the single peak was found to be intact, infectious, nuclease resistant AAV particles. This offers a significant advantage over the limited information one gains from UV spectrophotometry. This demonstrates the utility of chromatography for analysis and purification of viral vectors.

Cardiorespiratory responses and circulating metabolite concentrations in male and female adolescents during a simulated duathlon.

This study compared markers of the metabolic processes occurring in male and female adolescent triathletes from two age groups (over 15 years of age [O15] and under 15 years of age [U15]) during a laboratory based duathlon. Participants were tested on three separate occasions; two peak VO2 tests on a treadmill and cycle ergometer, and a third session involved a simulated duathlon (2 km run, 12 km ride and 4 km run for the O15 group or 1 km run, 8 km ride and 2 km run for the U15). Data collection included performance speed, cardiorespiratory responses and blood borne markers of exercise metabolism. The performance speeds selected by the two age groups did not differ. The mean relative percentage of VO2peak at which subjects participated were 79+/-3, 77+/-4%, for the O15 males and females, and 71+/-5 and 82+/-2%, for the U15 males and females, respectively. While the plasma metabolites of ammonia [NH3] and lactate [La] were not different between age groups and sex (p>0.05) there were however, higher concentrations recorded during the cycling phase when compared with the running phases (p < 0.05). The respective mean concentrations for NH3 and La were 80.5+/-5.6 microM, and 4.9+/-0.3 microM for cycling, and 56.3+/-2.7 microM, and 2.7+/-0.2 microM for the combined running phases.

Purification of myristoylated and nonmyristoylated neuronal calcium sensor-1 using single-step hydrophobic interaction chromatography.

Neuronal calcium sensors (NCSs) belong to a family of Ca(2+)-binding proteins, which serve important functions in neurotransmission, and are highly conserved from yeast to humans. Overexpression of the neuronal calcium sensor-1, called frequenin in the fruit fly and in frog, increases the release of neurotransmitters. Studying the functional role of frequenin in mammals and understanding its structural dynamics is critically dependent on the availability of active purified protein. Neuronal calcium sensors like other members of the family share common structural features: they contain four EF-hands as potential binding sites for Ca(2+) and an N-terminal consensus sequence for myristoylation. Previously, recoverin, distantly related to NCSs, has been expressed and purified from Escherichia coli, involving a combination of different chromatographic steps. NCS-1 has earlier been purified adopting a two-step procedure used for recoverin purification. We have overexpressed NCS-1 from rat in its myristoylated and nonmyristoylated form in E. coli and purified it from crude lysates using a single-step hydrophobic interaction chromatography. The purified protein was identified by Western blotting and mass spectrometry and assayed for its ability to bind Ca(2+) using a Ca(2+) shift assay, terbium fluorescence, and Stains-all binding. The present protocol provides a rapid, more efficient and simplified, single-step method for purifying NCS-1 for structural and functional studies. This method can also be applied to purify related proteins of the superfamily.