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The aim of this cross-sectional study was to determine the prevalence and identify determinants of reduced bone mineral density (BMD) in adults with cystic fibrosis (CF).Adults (88) with CF (mean¡SD age 29.9¡7.7 yrs; forced expiratory volume in one second (FEV1) 58.2¡21.5% of the predicted value) were studied. BMD at the lumbar spine (LS) and femoral neck (FN) and body composition were measured using dual-energy X-ray absorptiometry. Blood and urine were analysed for hormones, bone turnover markers, and the cytokines tumour necrosis factor-a, and interleukin-6 and -1b. FEV1 (% pred); CF genotype; malnutrition; history of growth, development or weight gain delays; and corticosteroid use were analysed.BMD Z-scores were -0.58¡1.30 (mean¡SD) at the LS and -0.24¡1.19 at the FN. Z-scores of ,-2.0 were found in 17% of subjects. Subjects who were homozygous or heterozygous for the DF508 mutation exhibited significantly lower Z-scores than those with no DF508 allele. Multiple linear regression showed that the DF508 genotype and male sex were independently associated with lower BMD at both sites. Other factors also independently associated with lower BMD included malnutrition, lower 25-hydroxyvitamin D level, lower fat-free mass and lower FEV1 (% pred).In conclusion, reduced bone mineral density in cystic fibrosis is associated with a number of factors, including DF508 genotype, male sex, greater lung disease severity and malnutrition.

Introduction The development of bedside methods to assess muscularity is an essential critical care nutrition research priority. We aimed to compare ultrasound‐derived muscle thickness at 5 landmarks with computed tomography (CT) muscle area at intensive care unit (ICU) admission. Secondary aims were to (1) combine muscle thicknesses and baseline covariates to evaluate correlation with CT muscle area and (2) assess the ability of the best‐performing ultrasound model to identify patients with low CT muscle area. Methods Adult patients who underwent CT scanning at the third lumbar area <72 hours after ICU admission were prospectively recruited. Muscle thickness was measured at mid‐upper arm, forearm, abdomen, and thighs. Low CT muscle area was determined using published cutoffs. Pearson correlation compared ultrasound‐derived muscle thickness and CT muscle area. Linear regression was used to develop ultrasound prediction models. Bland‐Altman analyses compared ultrasound‐predicted and CT‐measured muscle area. Results Fifty ICU patients were enrolled, aged 52 ± 20 years. Ultrasound‐derived muscle thickness at each landmark correlated with CT muscle area (P < .001). The sum of muscle thickness at mid‐upper arm and bilateral thighs, including age, sex, and the Charlson Comorbidity Index, improved the correlation with CT muscle area (r = 0.85; P < .001). Mean difference between ultrasound‐predicted and CT‐measured muscle area was −2 cm2 (95% limits of agreement, −40 cm2 to +36 cm2). The best‐performing ultrasound model demonstrated good ability to identify 14 patients with low CT muscle area (area under curve = 0.79). Conclusion Ultrasound shows potential for assessing muscularity at ICU admission (Clinicaltrials.gov NCT03019913).

1 Glibenclamide, a sulphonylurea oral hypoglycaemic agent is a widely used antagonist of cromakalimactivated K+ channels in smooth muscle.2 In isolated ring segments of the large circumflex coronary artery from the dog, glibenclamide (1-30 gM) caused a concentration-dependent reduction in both spontaneous isometric force and contractions induced by U46619, a thromboxane A2-mimetic.3 Glibenclamide behaved as a competitive antagonist of U46619 with an estimated pK, (-log KB) value of 6.2 by Schild regression analysis (slope 1.07). 4 Glibenclamide (30pM) was apparently selective since it had no effect on the concentration-contraction curves to endothelin-1, noradrenaline or KCL. 5 We suggest that this additional property of glibenclamide should be considered in any smooth muscle study where active force is raised by either the exogenous application or endogenous generation of thromboxane A2-

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Critically ill patients experience significant and rapid loss of skeletal muscle mass, which has been associated with negative clinical outcomes. The aetiology of muscle wasting is multifactorial and nutrition delivery may play a role. A systematic literature review was conducted to examine the association of energy and/or protein provision on changes in skeletal muscle mass in critically ill patients. Key databases were searched up until March 2016 to identify studies that measured skeletal muscle mass and/or total body protein (TBP) at 2 or more time points during acute critical illness (up to 2 weeks after an intensive care unit [ICU] stay). Studies were included if there was documentation of participant energy balance or mean energy delivered to participants during the time period between body composition measurements. Six studies met inclusion criteria. A variety of methods were used to assess skeletal muscle mass or TBP. Participants in included studies experienced differing levels of muscle loss (0%-22.5%) during the first 2 weeks of ICU admission. No association between energy and protein delivery and changes in skeletal muscle mass were observed. This review highlights that there is currently limited high-quality evidence to clearly define the association between energy and/or protein delivery and skeletal muscle mass changes in acute critical illness. Future studies in this area should be adequately powered, account for all potential confounding factors to changes in skeletal muscle mass, and detail all sources and quantities of energy and protein delivered to participants.

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Purpose:To determine the prevalence of sarcopenia and investigate relationships among body composition, muscle strength, and physical function in elderly women in low-level aged care.Subjects and methods:Sixty-three ambulatory women (mean age 86 years) participated in this cross-sectional study where body composition was determined by dual energy X-ray absorptiometry (DXA); ankle, knee, and hip strength by the Nicholas Manual Muscle Tester; and physical function by ‘timed up and go’ (TUG) and walking speed (WS) over 6 meters. Body composition data from a female reference group (n = 62, mean age 29 years) provided cut-off values for defining sarcopenia.Results:Elderly women had higher body mass index (P < 0.001), lower lean mass (P < 0.001), and higher fat mass (P < 0.01) than the young reference group. Only a small proportion (3.2%) had absolute sarcopenia (defined by appendicular skeletal muscle mass/height squared) whereas 37% had relative sarcopenia class II (defined by percentage skeletal muscle mass). Scores for TUG and WS indicated relatively poor physical function, yet these measures were not associated with muscle mass or indices of sarcopenia. In multivariate analysis, only hip abductor strength predicted both TUG and WS (both P = 0.01).Conclusion:Hip strength is a more important indicator of physical functioning than lean mass. Measurement of hip strength may therefore be a useful screening tool to detect those at risk of functional decline and requirement for additional care. Further longitudinal studies with a range of other strength measures are warranted.