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SummaryThe National Bone Health Alliance (NBHA) recommends standardized sample handling and patient preparation for C-terminal telopeptide of type I collagen (CTX-I) and N-terminal propeptide of type I procollagen (PINP) measurements to reduce pre-analytical variability. Controllable and uncontrollable patient-related factors are reviewed to facilitate interpretation and minimize pre-analytical variability.IntroductionThe IOF and the International Federation of Clinical Chemistry (IFCC) Bone Marker Standards Working Group have identified PINP and CTX-I in blood to be the reference markers of bone turnover for the fracture risk prediction and monitoring of osteoporosis treatment. Although used in clinical research for many years, bone turnover markers (BTM) have not been widely adopted in clinical practice primarily due to their poor within-subject and between-lab reproducibility. The NBHA Bone Turnover Marker Project team aim to reduce pre-analytical variability of CTX-I and PINP measurements through standardized sample handling and patient preparation.MethodsRecommendations for sample handling and patient preparations were made based on review of available publications and pragmatic considerations to reduce pre-analytical variability. Controllable and un-controllable patient-related factors were reviewed to facilitate interpretation and sample collection.ResultsSamples for CTX-I must be collected consistently in the morning hours in the fasted state. EDTA plasma is preferred for CTX-I for its greater sample stability. Sample collection conditions for PINP are less critical as PINP has minimal circadian variability and is not affected by food intake. Sample stability limits should be observed. The uncontrollable aspects (age, sex, pregnancy, immobility, recent fracture, co-morbidities, anti-osteoporotic drugs, other medications) should be considered in BTM interpretation.ConclusionAdopting standardized sample handling and patient preparation procedures will significantly reduce controllable pre-analytical variability. The successful adoption of such recommendations necessitates the close collaboration of various stakeholders at the global stage, including the laboratories, the medical community, the reagent manufacturers and the regulatory agencies.

High-resolution peripheral computed tomography (HR-pQCT) was developed to image bone microarchitecture in vivo at peripheral skeletal sites. Since the introduction of HR-pQCT in 2005, clinical research to gain insight into pathophysiology of skeletal fragility and to improve prediction of fractures has grown. Meanwhile, the second-generation HR-pQCT device has been introduced, allowing novel applications such as hand joint imaging, assessment of subchondral bone and cartilage thickness in the knee, and distal radius fracture healing. This article provides an overview of the current clinical applications and guidance on interpretation of results, as well as future directions. Specifically, we provide an overview of (1) the differences and reference data for HR-pQCT variables by age, sex, and race/ethnicity; (2) fracture risk prediction using HR-pQCT; (3) the ability to monitor response of anti-osteoporosis therapy with HR-pQCT; (4) the use of HR-pQCT in patients with metabolic bone disorders and diseases leading to secondary osteoporosis; and (5) novel applications of HR-pQCT imaging. Finally, we summarize the status of the application of HR-pQCT in clinical practice and discuss future directions. From the clinical perspective, there are both challenges and opportunities for more widespread use of HR-pQCT. Assessment of bone microarchitecture by HR-pQCT improves fracture prediction in mostly normal or osteopenic elderly subjects beyond DXA of the hip, but the added value is marginal. The prospects of HR-pQCT in clinical practice need further study with respect to medication effects, metabolic bone disorders, rare bone diseases, and other applications such as hand joint imaging and fracture healing. The mostly unexplored potential may be the differentiation of patients with only moderately low BMD but severe microstructural deterioration, which would have important implications for the decision on therapeutical interventions.

Assessment of the progression of abdominal aortic calcification (AAC) may be a surrogate marker of the impact of physical function on cardiovascular risk. Our aim was to assess the risk of rapid AAC progression in older men with low relative appendicular lean mass (RALM) and poor physical function. Prospective cohort study. Community-dwelling older men. 621 men aged 50–85 followed prospectively (baseline, 3 and 7.5 years). Body composition was assessed by DXA. Poor physical function was defined as incapacity to perform ≥1 of 5 clinical tests (balance, muscle strength). AAC was assessed using Kauppila's semiquantitative score. Reclassification improvement was assessed by comparing the areas under the curve (AUC) using DeLong's method. Rapid AAC progression (>0.6 point/year) was found in 168 men (27.1%). After adjustment for confounders including baseline AAC, the risk of rapid AAC progression increased with lower RALM (OR=1.42/SD, 95%CI: 1.09–1.86, p<0.01) and was higher in the lowest (<7.5kg/m2) vs. highest (>8.6kg/m2) quartile (OR=2.15, 95%CI: 1.17–3.95, p<0.01). Poor physical performance was associated with rapid AAC progression (OR=2.76, 95%CI: 1.48–5.91, p<0.005). Low RALM (<7.84kg/m2 defined using Youden's index) and poor physical function contributed to the risk of rapid AAC progression jointly. Men who had low RALM and poor physical function had higher risk of rapid AAC progression vs. men without these traits (OR=4.66, 95%CI: 1.72–12.62, p<0.05). RALM and physical function improved the identification of men with rapid AAC progression (AAUC=0.026, 95%CI: 0.005–0.046, p<0.05) after adjustment for confounders including baseline AAC score. Low RALM and poor physical function are associated with higher risk of rapid AAC progression and possibly represent another measure of cardiovascular risk.

Introduction The aim was to analyse data on the use of biochemical bone turnover markers (BTM) in postmenopausal osteoporosis. Methods We carried out a comparative analysis of the most important papers concerning BTM in postmenopausal osteoporosis that have been published recently. Results The BTM levels are influenced by several factors. They are moderately correlated with BMD and subsequent bone loss. Increased levels of bone resorption markers are associated with a higher risk of fracture. Changes in the BTM during the anti-osteoporotic treatment (including combination therapy) reflect the mechanisms of action of the drugs and help to establish their effective doses. Changes in the BTM during the anti-resorptive treatment are correlated with their anti-fracture efficacy. Conclusion Biological samples should be obtained in a standardised way. BTM cannot be used for prediction of the accelerated bone loss at the level of the individual. BTM help to detect postmenopausal women who are at high risk of fracture; however, adequate practical guidelines are lacking. BTM measurements taken during the anti-resorptive therapy help to identify non-compliers. They may improve adherence to the anti-resorptive therapy and the fall in the BTM levels that exceeds the predefined threshold improves patients’ persistence with the treatment. There are no guidelines concerning the use of BTM in monitoring anti-osteoporotic therapy in postmenopausal women.

SummaryThis systematic review summarizes the effect of combined exercise and nutrition intervention on muscle mass and muscle function. A total of 37 RCTs were identified. Results indicate that physical exercise has a positive impact on muscle mass and muscle function in subjects aged 65 years and older. However, any interactive effect of dietary supplementation appears to be limited.IntroductionIn 2013, Denison et al. conducted a systematic review including 17 randomized controlled trials (RCTs) to explore the effect of combined exercise and nutrition intervention to improve muscle mass, muscle strength, or physical performance in older people. They concluded that further studies were needed to provide evidence upon which public health and clinical recommendations could be based. The purpose of the present work was to update the prior systematic review and include studies published up to October 2015.MethodsUsing the electronic databases MEDLINE and EMBASE, we identified RCTs which assessed the combined effect of exercise training and nutritional supplementation on muscle strength, muscle mass, or physical performance in subjects aged 60 years and over. Study selection and data extraction were performed by two independent reviewers.ResultsThe search strategy identified 21 additional RCTs giving a total of 37 RCTs. Studies were heterogeneous in terms of protocols for physical exercise and dietary supplementation (proteins, essential amino acids, creatine, β-hydroxy-β-methylbuthyrate, vitamin D, multi-nutrients, or other). In 79% of the studies (27/34 RCTs), muscle mass increased with exercise but an additional effect of nutrition was only found in 8 RCTs (23.5%). Muscle strength increased in 82.8% of the studies (29/35 RCTs) following exercise intervention, and dietary supplementation showed additional benefits in only a small number of studies (8/35 RCTS, 22.8%). Finally, the majority of studies showed an increase of physical performance following exercise intervention (26/28 RCTs, 92.8%) but interaction with nutrition supplementation was only found in 14.3% of these studies (4/28 RCTs).ConclusionPhysical exercise has a positive impact on muscle mass and muscle function in healthy subjects aged 60 years and older. The biggest effect of exercise intervention, of any type, has been seen on physical performance (gait speed, chair rising test, balance, SPPB test, etc.). We observed huge variations in regard to the dietary supplementation protocols. Based on the included studies, mainly performed on well-nourished subjects, the interactive effect of dietary supplementation on muscle function appears limited.

Summary The aim of this study was to determine the relationship between reduced muscle mass (sarcopenia) and areal bone mineral density (BMD a ) in middle-aged and elderly community-dwelling European men. Men with sarcopenia had significantly lower BMD a and were more likely to have osteoporosis compared with men without sarcopenia. Introduction In men, the relationship between reduced muscle mass (sarcopenia) and BMD a is unclear. This study aimed to determine this relationship in middle-aged and elderly community-dwelling men. Methods Men aged 40–79 years from the Manchester (UK) and Leuven (Belgium) cohorts of the European Male Ageing Study were invited to attend for assessment including dual-energy X-ray absorptiometry, from which appendicular lean mass (aLM), fat mass (FM) and whole-body, spine and hip BMD a were determined. Relative appendicular skeletal muscle mass (RASM) was calculated as aLM/height². Muscle strength was assessed in subjects from Leuven. Sarcopenia was defined by RASM at <7.26 kg/m² and by the recent definition of the European Working Group on Sarcopenia in Older People (RASM at <7.26 kg/m 2 plus low muscle function). Linear regression was used to determine the associations between aLM, FM, muscle strength and BMD a and logistic regression to determine the association between sarcopenia and osteoporosis. Results Six hundred seventy-nine men with a mean age of 59.6 (SD = 10.7), contributed data to the analysis; 11.9 % were sarcopenic by the conventional definition. After adjustment for age and centre, aLM, RASM and FM were positively associated with BMD a . Men with RASM at <7.26 kg/m² had significantly lower BMD a compared with those with RASM at ≥7.26 kg/m 2 . In a multivariable model, aLM was most consistently associated with BMD a . Men with sarcopenia were more likely to have osteoporosis compared with those with normal RASM (odds ratio = 3.0; 95 % CI = 1.6–5.8). Conclusions Sarcopenia is associated with low BMD a and osteoporosis in middle-aged and elderly men. Further studies are necessary to assess whether maintaining muscle mass contributes to prevent osteoporosis.

Multi-piped impellers (name proposed by the authors) represent an innovative approach to the design of rotodynamic pumps operating at the specific speed of nq<10. In such a construction the energy increase is caused by the flow of liquid through the internal impeller passages as well as by an external flow around the passages, and sensible designing of such a construction is extremely difficult. The study investigates the flow phenomena and impact of the external shape of a multi-pipe impeller on the efficiency of the process of energy transfer into liquid. The main research method involves computational fluid dynamics (CFD) simulations.

Vortex pumps are widely used in wide range of hydro-transportation applications. Main disadvantage of this type of pump design is low efficiency. Despite ongoing effort to improve vortex impeller performance precise algorithm for their optimal design doesn't exist. One of the ideas is to use winglets (super-vortex) on the tip of the impeller blades. Conducted literature studies have shown that there is not yet clarified principle of winglet design. Authors have performed numerical simulations and measurements for three different arrangements of winglets with varying impeller coverages. From the obtained results recommendation for optimal winglet placement is deducted.

Summary The Committee of Scientific Advisors of International Osteoporosis Foundation (IOF) recommends that papers describing the descriptive epidemiology of osteoporosis using bone mineral density (BMD) at the femoral neck include T-scores derived from an international reference standard. Introduction The prevalence of osteoporosis as defined by the T-score is inconsistently reported in the literature which makes comparisons between studies problematic. Methods The Epidemiology and Quality of Life Working Group of IOF convened to make its recommendations and endorsement sought thereafter from the Committee of Scientific Advisors of IOF. Results The Committee of Scientific Advisors of IOF recommends that papers describing the descriptive epidemiology of osteoporosis using BMD at the femoral neck include T-scores derived from the National Health and Nutrition Examination Survey III reference database for femoral neck measurements in Caucasian women aged 20–29 years. Conclusions It is expected that the use of the reference standard will help resolve difficulties in the comparison of results between studies and the comparative assessment of new technologies.

This work focuses on methods of submersible sewage mixer performance evaluation comparison. In the paper an experiment with a submersible mixer with a published and known geometry has been presented. The authors measured thrust, torque rotation speed and electric power. Experiment was compared with results obtained with a steady state numerical simulation. Next CFD results were checked with a theoretical approach for the mixing range. Both theoretical and numerical methods showed good applicability for the industry.