Treadmill walking economy is not affected by body fat and body mass index in adults.

To determine whether body fat and body mass index (BMI) affect the energy cost of walking (Cw; J/kg/m), ventilation, and gas exchange data from 205 adults (115 females; percent body fat range = 3.0%-52.8%; BMI range = 17.5-43.2 kg/m2) were obtained at rest and during treadmill walking at 1.34 m/s to calculate gross and net Cw. Linear regression was used to assess relationships between body composition indices, Cw, and standing metabolic rate (SMR). Unpaired t-tests were used to assess differences between sex, and one-way ANOVA was used to assess differences by BMI categories: normal weight, <25.0 kg/m2; overweight, 25.0-29.9 km/m2; and obese, ≥30 kg/m2. Net Cw was not related to body fat percent, fat mass, or BMI (all R2 ≤ 0.011). Furthermore, mean net Cw was similar by sex (male: 2.19 ± 0.30 J/kg/m; female: 2.24 ± 0.37 J/kg/m, p = 0.35) and across BMI categories (normal weight: 2.23 ± 0.36 J/kg/m; overweight: 2.18 ± 0.33 J/kg/m; obese: 2.26 ± 0.31, p = 0.54). Gross Cw and SMR were inversely associated with percent body fat, fat mass, and BMI (all R2 between 0.033 and 0.270; all p ≤ 0.008). In conclusion, Net Cw is not influenced by body fat percentage, total body fat, and BMI and does not differ by sex.

Assessment Methods of Body Fat in Recreational Marathon Runners: Bioelectrical Impedance Analysis versus Skinfold Thickness.

The aim of the present study was to examine (a) the relationship of body fat (BF) assessed by bioimpedance analysis (BIA) and skinfold thickness (SKF) and (b) the variation of BF by age depending on the assessment method. Participants were 32 women and 134 men recreational marathon runners, who were tested for BF using both assessment methods (BIA and SKF). Rc between BIA and SKF assessment methods was 0.803 (95% CI; 0.640, 0.897) in women and 0.568 (95% CI; 0.481, 0.644) in men. A large main effect of the assessment method on BF was observed (p < 0.001, η 2 = 0.156) with SKF presenting higher BF than BIA by 2.9%. The difference between SKF and BIA was 3.9 ± 2.7% (95% confidence intervals, CI; 3.4; 4.3, p < 0.001) in men, whereas no difference was found in women (-0.9 ± 2.9%; 95% CI; -1.9; -0.2, p = 0.101). BF correlated with age with small magnitude (BIA, r = 0.18, p = 0.036; SKF, r = 0.23, p = 0.007) in men, i.e., the older the age, the higher the BF. A similar trend of moderate magnitude was observed in women for BIA (r = 0.45, p = 0.011), but not for SKF (r = 0.33, p = 0.067). In conclusion, practitioners involved in the training of recreational runners would be advised to consider that BIA elicits a lower BF value than the SKF method in men.

Assessment of the association between body composition and risk of non-alcoholic fatty liver.

Non-alcoholic fatty liver disease (NAFLD) is defined as the condition of fat accumulation in the liver. This cross-sectional study aimed to investigate the relationship between body composition and fatty liver and determine of cut-off point for predicting NAFLD. Samples were selected from the nutrition clinic from 2016 to 2017 in Tehran, Iran. The liver steatosis was calculated using the CAP score through the FiroScan™ and body composition was measured using the dual-energy X-ray absorptiometry scan method. A total of 2160 patients participated in this study, 745 (34.5%) subjects had NAFLD. We found that fat-free tissue was inversely and fat tissue was directly correlated with the risk of NAFLD in almost all factors and the risk of developing NAFLD increases if the total fat exceeds 32.23% and 26.73% in women and men and abdominal fat exceeds 21.42% and 13.76% in women and men, respectively. Finally, we realized that the total fat percent had the highest AUC (0.932 for men and 0.917 for women) to predict the risk of NAFLD. Overall, the likelihood of NAFLD development rose significantly with increasing the amount of total fat and abdominal fat from the cut-off point level.

Celastrol alleviates metabolic disturbance in high-fat diet-induced obese mice through increasing energy expenditure by ameliorating metabolic inflammation.

Celastrol, a natural triterpene, has been shown to treat obesity and its related metabolic disorders. In this study, we first assessed the relationship between the antiobesity effects of celastrol and its antiinflammatory activities. Our results showed that celastrol can reduce weight gain, ameliorate glucose intolerance, insulin resistance, and dyslipidemia without affecting food intake in high-fat diet-induced obese mice. A CLAMS was used to clarify the improvement of metabolic profiles was attribute to increased adipose thermogenesis after celastrol treatment. Further studies found that celastrol decreased the infiltration of macrophage as well as its inflammatory products (IL-1ß, IL-18, MCP-1α, and TNF-α) in liver and adipose tissues, which also displayed an obvious inhibition of TLR3/NLRP3 inflammasome molecules. This study demonstrated that celastrol could be a potential drug for treating metabolic disorders, the underlying mechanism is related to ameliorating metabolic inflammation, thus increasing body energy expenditure.

Assessment of Age-Induced Changes in Body Fat Percentage and BMI Aided by Bayesian Modelling: A Cross-Sectional Cohort Study in Middle-Aged and Older Adults.

BACKGROUND: Loss of fat-free mass (FFM) and gain in body fat (BF) are the key disability risk factors, also instrumental in perpetuating already existing functional disorders. Obesity construed in terms of body mass index (BMI) values, in view of undesirable gain in BF, is a risk factor for cardio-metabolic disorders. Both detrimental processes clearly evidence a scope of involutionary changes characteristic of an aging population, also standing for one of its greatest burdens. PURPOSE: The present study aimed to assess the changes in body composition (BC), in conjunction with the relationship between BF% and BMI, for defining overweight and obesity status in middle-aged and older adults, against the select indicator variables under study. MATERIALS AND METHODS: The study involved 4799 individuals (33.7% men), PONS Project participants, aged 43-64 years. BF% was measured with the aid of bioelectrical impedance analysis (BIA) method. Age-induced changes in BC were determined against BF%, fat mass (FM), FFM, BMI, fat mass index (FMI), and fat-free mass index (FFMI). The relationship between BF% and BMI was established with the aid of Bayesian regression models, adjusted for gender and age. RESULTS: In both genders, BF% increased with age at a similar annual rate. The reduction of FFM was noted mainly in men, which in conjunction with BF% gain ensured BMI stability. The increase in BF% in women with stable FFM affected an increase in BMI. Regardless of the BMI threshold, the anticipated (predicted) BF% increased with age in both genders. CONCLUSION: Monitoring of BC is of particular importance in older adults, in view of appreciably better characteristics of both the short- and long-term health predictors, as well as overall potential for developing specifically targeted, effective health interventions.

Pasteurized Akkermansia muciniphila increases whole-body energy expenditure and fecal energy excretion in diet-induced obese mice.

Accumulating evidence points to Akkermansia muciniphila as a novel candidate to prevent or treat obesity-related metabolic disorders. We recently observed, in mice and in humans, that pasteurization of A. muciniphila increases its beneficial effects on metabolism. However, it is currently unknown if the observed beneficial effects on body weight and fat mass gain are due to specific changes in energy expenditure. Therefore, we investigated the effects of pasteurized A. muciniphila on whole-body energy metabolism during high-fat diet feeding by using metabolic chambers. We confirmed that daily oral administration of pasteurized A. muciniphila alleviated diet-induced obesity and decreased food energy efficiency. We found that this effect was associated with an increase in energy expenditure and spontaneous physical activity. Strikingly, we discovered that energy expenditure was enhanced independently from changes in markers of thermogenesis or beiging of the white adipose tissue. However, we found in brown and white adipose tissues that perilipin2, a factor associated with lipid droplet and known to be altered in obesity, was decreased in expression by pasteurized A. muciniphila. Finally, we observed that treatment with pasteurized A. muciniphila increased energy excretion in the feces. Interestingly, we demonstrated that this effect was not due to the modulation of intestinal lipid absorption or chylomicron synthesis but likely involved a reduction of carbohydrates absorption and enhanced intestinal epithelial turnover. In conclusion, this study further dissects the mechanisms by which pasteurized A. muciniphila reduces body weight and fat mass gain. These data also further support the impact of targeting the gut microbiota by using specific bacteria to control whole-body energy metabolism.

Body fat percent assessment between electrical impedance myography and dual X-ray absorptiometry.

OBJECTIVES: To compare total and regional body fat percent (BF%) measurements obtained using a handheld electrical impedance myography (EIM) device in comparison to BF% measured by dual X-ray absorptiometry (DXA). METHODS: Sixty-nine male and female (33 males/36 females; age = 21.9 ± 2.0 years, body mass index = 24.5 ± 3.6 kg/m2 ) college-age individuals participated in this study. Each participant's total and regional (ie, upper arms, upper legs, trunk) BF% was estimated using EIM and DXA. Metallic markers were used to delineate regional boundaries for analysis, including upper arms (biceps/triceps), upper legs (quadriceps/hamstrings), and trunk (abdominal region/low back region). Paired t-tests assessed the accuracy of BF% values estimated from EIM in comparison to BF% measured by DXA. RESULTS: Observations revealed EIM reported significantly lower BF% for upper left arm (P < .001), upper right arm (P < .001), upper right leg (P = .002), and trunk (P < .001) values. However, no significant differences were observed in total (P = .434) and upper left leg (P = .855) BF% between the two devices. CONCLUSIONS: This study's observations suggest that, EIM may be an accurate field method for measuring total BF%, but not regional BF%.

Sleep pattern, obesity and healthcare expenditures in Brazilian adults / Padrões do sono, obesidade e despesas em saúde com brasileiros adultos

Abstract The aim of this study was to analyze the relationship between sleep pattern and healthcare expenditures in adults, as well as to identify whether physical activity, biochemical markers and obesity affect this relationship. The sample was composed of 168 adults aged ≥ 50 years attended by two Basic Healthcare Units in Presidente Prudente, SP, Brazil. Health expenditure, sleep pattern, anthropometry, adiposity index, physical activity, metabolic and cardiovascular variables were assessed. Statistical analyses were performed using Kruskal-Wallis, Mann-Whitney and Spearman tests. Sleep disorders were positively correlated to higher costs with medicines and negatively correlated to costs with laboratory tests, even after adjusts by confounders. In addition, healthcare costs were also correlated to physical activity score, blood pressure, obesity and metabolic variables. Severe sleep disorders and high percentage of body fat were associated with increased use of medications. Sleep pattern is correlated to primary care healthcare costs, obesity and physical activity level.

Resumo O objetivo deste estudo foi analisar a relação entre padrão de sono e despesas de saúde em adultos, bem como identificar se atividade física, marcadores bioquímicos e obesidade afetam esse relacionamento. A amostra foi composta por 168 adultos com idade ≥ 50 anos atendidos por duas unidades básicas de saúde em Presidente Prudente, SP, Brasil. Foram avaliadas as despesas de saúde, padrões do sono, antropometria, atividade física, variáveis metabólicas e cardiovasculares. Foram utilizados Kruskal-Wallis, Mann-Whitney e Spearman. Os distúrbios do sono foram correlacionados positivamente com os custos mais elevados com medicamentos e negativamente com os custos com testes laboratoriais, mesmo após ajuste por fatores de confusão. Além disso, os custos de saúde também foram correlacionados ao escore de atividade física, pressão arterial, obesidade e variáveis metabólicas. Distúrbios graves do sono e alta porcentagem de gordura corporal foram associados ao aumento do uso de medicamentos. O padrão de sono está correlacionado com os custos de cuidados de saúde primários, obesidade e atividade física.

Sleep pattern, obesity and healthcare expenditures in Brazilian adults.

The aim of this study was to analyze the relationship between sleep pattern and healthcare expenditures in adults, as well as to identify whether physical activity, biochemical markers and obesity affect this relationship. The sample was composed of 168 adults aged ≥ 50 years attended by two Basic Healthcare Units in Presidente Prudente, SP, Brazil. Health expenditure, sleep pattern, anthropometry, adiposity index, physical activity, metabolic and cardiovascular variables were assessed. Statistical analyses were performed using Kruskal-Wallis, Mann-Whitney and Spearman tests. Sleep disorders were positively correlated to higher costs with medicines and negatively correlated to costs with laboratory tests, even after adjusts by confounders. In addition, healthcare costs were also correlated to physical activity score, blood pressure, obesity and metabolic variables. Severe sleep disorders and high percentage of body fat were associated with increased use of medications. Sleep pattern is correlated to primary care healthcare costs, obesity and physical activity level.

Anthropometry, body fat and central adiposity in LBW and NBW Indian children aged 3.5 to 4 years.

BACKGROUND: India has a high prevalence of low birth weight. Evidence indicates that poor fetal growth and rapid postnatal weight gain are associated with adiposity. OBJECTIVES: (i) To study the differences between the anthropometry, body fat measures of LBW and NBW children and (ii) To find out if there is any relationship between birth weight, change in weight SD and body fat measures of these children. STUDY DESIGN: Cross-sectional study. SUBJECTS: We studied 396 children aged between 3.5 and 4 years who were beneficiaries of government-run anganwadis in urban slums of Mumbai city, India. OUTCOME MEASURES: Birth weight, current weight, height, skinfold thicknesses and waist circumference. Change in weight SD and body fat (%) were calculated. WHOAnthro was used to compute the z scores. Parent's education, income and breastfeeding history was recorded. RESULTS: The mean change in weight SD of LBW and NBW groups were 1.01 ±â€¯1.4 and -0.73 ±â€¯1.13 respectively (p < 0.001). LBW children were lighter and shorter than NBW ones but had similar body fat (%) and central adiposity measures. In LBW and NBW children, birth weight Z score and change in weight SD were positively related to body fat (%) and waist circumference. CONCLUSION: Children in this study belonged to low socioeconomic section. Despite this, LBW displayed a tendency towards accumulating body fat particularly, abdominal fat for lower body weight. Birth weight and postnatal weight change predict body fat and waist circumference in LBW and NBW children.

Assessment of Vascular Tone Responsiveness using Isolated Mesenteric Arteries with a Focus on Modulation by Perivascular Adipose Tissues.

Altered vascular tone responsiveness to pathophysiological stimuli contributes to the development of a wide range of cardiovascular and metabolic diseases. Endothelial dysfunction represents a major culprit for the reduced vasodilatation and enhanced vasoconstriction of arteries. Adipose (fat) tissues surrounding the arteries play important roles in the regulation of endothelium-dependent relaxation and/or contraction of the vascular smooth muscle cells. The cross-talks between the endothelium and perivascular adipose tissues can be assessed ex vivo using mounted blood vessels by a wire myography system. However, optimal settings should be established for arteries derived from animals of different species, ages, genetic backgrounds and/or pathophysiological conditions.

Assessment of Mechanical Properties of Tissue in Breast Cancer-Related Lymphedema Using Ultrasound Elastography.

Breast cancer-related lymphedema is a consequence of a malfunctioning lymphatic drainage system resulting from surgery or some other form of treatment. In the initial stages, minor and reversible increases in the fluid volume of the arm are evident. As the stages progress over time, the underlying pathophysiology dramatically changes with an irreversible increase in arm volume most likely due to a chronic local inflammation leading to adipose tissue hypertrophy and fibrosis. Clinicians have subjective ways to stage the degree and severity such as the pitting test which entails manually comparing the elasticity of the affected and unaffected arms. Several imaging modalities can be used but ultrasound appears to be the most preferred because it is affordable, safe, and portable. Unfortunately, ultrasonography is not typically used for staging lymphedema, because the appearance of the affected and unaffected arms is similar in B-mode ultrasound images. However, novel ultrasound techniques have emerged, such as elastography, which may be able to identify changes in mechanical properties of the tissue related to detection and staging of lymphedema. This paper presents a novel technique to compare the mechanical properties of the affected and unaffected arms using quasi-static ultrasound elastography to provide an objective alternative to the current subjective assessment. Elastography is based on time delay estimation (TDE) from ultrasound images to infer displacement and mechanical properties of the tissue. We further introduce a novel method for TDE by incorporating higher order derivatives of the ultrasound data into a cost function and propose a novel optimization approach to efficiently minimize the cost function. This method works reliably with our challenging patient data. We collected radio frequency ultrasound data from both arms of seven patients with stage 2 lymphedema, at six different locations in each arm. The ratio of strain in skin, subcutaneous fat, and skeletal muscle divided by strain in the standoff gel pad was calculated in the unaffected and affected arms. The p -values using a Wilcoxon sign-rank test for the skin, subcutaneous fat, and skeletal muscle were 1.24×10-5 , 1.77×10-8 , and 8.11×10-7 respectively, showing differences between the unaffected and affected arms with a very high level of significance.

An assessment of ocular elasticity using real time ultrasound and ocular response analyzer in active or remission rheumatoid arthritis.

PURPOSE: To investigate the elasticity of ocular structures in patients with rheumatoid arthritis (RA) without ocular involvement. METHODS: The study included 56 RA patients (study group) and 24 healthy volunteers as the control group. The rheumatoid arthritis patients were divided into two subgroups as those in active phase (Group 1, n = 25) or in remission phase (Group 2, n = 31) according to the disease activity index (DAS 28) score. The elastography values of the ratio of orbital fat-sclera (ROF/S) were measured with real-time US elastography, and corneal mechanical values were measured with the Reichert Ocular Response Analyzer in each eye. RESULTS: The mean ROF/S value was 5.2 ± 1.8 in Group 1, 0.7 ± 0.4 Group 2, and 0.6 ± 0.1 in the control group. There was a significant difference between the Group 1 and control group with regard to ROF/S (p < 0.001), but no significant difference was determined between Group 2 and control group (p > 0.05). The mean ROF/S value was a significant difference between the Group 1 and 2 (p < 0.001). ROF/S was significantly correlated with DAS-28 and C-reactive protein (CRP) (r = 0.816, p < 0.001 and r = 0.259, p = 0.006). CONCLUSIONS: ROF/S was significantly increased in patients in the active phase of RA. Findings revealed that ocular tissue structural changes may occur in the active phase and these could be related to ocular complications as a prognostic factor.

Ethnic differences in fat and muscle mass and their implication for interpretation of bioelectrical impedance vector analysis.

According to the World Health Organization Expert Consultation, current body mass index (BMI) cut-offs should be retained as an international classification. However, there are ethnic differences in BMI-associated health risks that may be caused by differences in body fat or skeletal muscle mass and these may affect the interpretation of phase angle and bioelectrical impedance vector analysis (BIVA). Therefore, the aim of this study was to compare body composition measured by bioelectrical impedance analysis among 1048 German, 1026 Mexican, and 995 Japanese adults encompassing a wide range of ages and BMIs (18-78 years; BMI, 13.9-44.3 kg/m2). Regression analyses between body composition parameters and BMI were used to predict ethnic-specific reference values at the standard BMI cut-offs of 18.5, 25, and 30 kg/m2. German men and women had a higher fat-free mass per fat mass compared with Mexicans. Normal-weight Japanese were similar to Mexicans but approached the German phenotype with increasing BMI. The skeletal muscle index (SMI, kg/m2) was highest in Germans, whereas in BIVA, the Mexican group had the longest vector, and the Japanese group had the lowest phase angle and the highest extracellular/total body water ratio. Ethnic differences in regional partitioning of fat and muscle mass at the trunk and the extremities contribute to differences in BIVA and phase angle. In conclusion, not only the relationship between BMI and adiposity is ethnic specific; in addition, fat distribution, SMI, and muscle mass distribution vary at the same BMI. These results emphasize the need for ethnic-specific normal values in the diagnosis of obesity and sarcopenia.

Low dose radiation, inflammation, cancer and chemoprevention.

PURPOSE: Recently, new studies have brought to light the potential risks of low dose radiation (LDR) in cancer. In this review, we discuss in detail the detrimental effects of LDR in some model organisms and animal models, as well as potential risks to human beings from some routine medical screening procedures. Furthermore, cellular mechanisms by which LDR exerts its negative effects like endoplasmic reticulum stress, epigenetic changes and microRNAs are also reviewed. A few studies are discussed that have reported some benefits of LDR through changes in energy metabolism. Lastly, we focus on breast cancer, one of the predominant forms of cancer potentially affected by LDR and some of the benefits of n-3 polyunsaturated fatty acids (PUFA) as dietary compounds that offer protection against radiation effects on cancer cells and cancer progression. CONCLUSIONS: Overall, LDR exerts mainly damaging effects through diverse cell and molecular mechanisms, with a few beneficial effects reported. In some cancers, surrounding adipose tissue of the breast may contribute to obesity-related cancer. Further, preclinical data suggest that anti-inflammatory dietary compounds such as PUFA and other dietary interventions may protect against radiation effects on cancer cells and cancer progression.

Evidence on nutritional assessment techniques and parameters used to determine the nutritional status of children and adolescents: systematic review.

This article aims to review systematically the evidence on nutritional assessment techniques and parameters used to determine the nutritional status of children and adolescents. The literature review and the selection of publications were performed using the Medline, Lilacs, SciELO, Embase, personal files. 17 studies were identified, 7 addressed the anthropometric indices as the main outcome, 7 analyzed the growth and development of children and adolescents through growth curves, and the remainder surveyed body composition. In general, all met the quality criteria, unless 6 of the articles who did not discuss the limitations. The literature review suggests several techniques and parameters that can be applied to determine the nutritional status of children and adolescents from different countries. Growth graphs are essential to assess the health of children, but depend greatly of the growth tables used. Although BMI can be practical, it does not distinguish body fat from lean mass. The best interpretation of anthropometry will depend of valid reference values for age range of the study population. BIA is a quick feasible method, but the measurement has some various nationalities.

Evidence on nutritional assessment techniques and parameters used to determine the nutritional status of children and adolescents: systematic review / Evidência sobre técnicas e parâmetros de avaliação nutricional para crianças e adolescentes: revisão sistemática

Abstract This article aims to review systematically the evidence on nutritional assessment techniques and parameters used to determine the nutritional status of children and adolescents. The literature review and the selection of publications were performed using the Medline, Lilacs, SciELO, Embase, personal files. 17 studies were identified, 7 addressed the anthropometric indices as the main outcome, 7 analyzed the growth and development of children and adolescents through growth curves, and the remainder surveyed body composition. In general, all met the quality criteria, unless 6 of the articles who did not discuss the limitations. The literature review suggests several techniques and parameters that can be applied to determine the nutritional status of children and adolescents from different countries. Growth graphs are essential to assess the health of children, but depend greatly of the growth tables used. Although BMI can be practical, it does not distinguish body fat from lean mass. The best interpretation of anthropometry will depend of valid reference values for age range of the study population. BIA is a quick feasible method, but the measurement has some various nationalities.

Resumo O objetivo deste artigo é revisar sistematicamente as evidências sobre as técnicas de avaliação nutricional e parâmetros utilizados para determinar o estado nutricional em crianças e adolescentes. Revisão da literatura com busca nas bases de dados, Medline, Lilacs, SciELO e Embase, além de arquivos pessoais. Identificamos 17 artigos que relatavam dados de diferentes populações, sete estudos abordaram os índices antropométricos, quatro o crescimento e o desenvolvimento de crianças e adolescentes por meio de curvas de crescimento, e o restante a composição corporal. Todos preencheram os critérios de qualidade, com exceção das limitações. A revisão da literatura sugere diversas técnicas e parâmetros que podem ser aplicados para determinar o estado nutricional de crianças e adolescentes de diferentes países. Gráficos de crescimento são essenciais para avaliar a saúde de crianças, mas depende muito das tabelas de crescimento utilizadas. Embora o IMC seja prático, não distingue a gordura corporal de massa magra. Existem várias técnicas para avaliar proporções, tamanho e composição corporal. A melhor interpretação da antropometria dependerá de valores de referência válidos para a faixa etária da população estudada. BIA é um método factível, mas tem algumas limitações para a realização do exame.

WISP-1 drives bone formation at the expense of fat formation in human perivascular stem cells.

The vascular wall within adipose tissue is a source of mesenchymal progenitors, referred to as perivascular stem/stromal cells (PSC). PSC are isolated via fluorescence activated cell sorting (FACS), and defined as a bipartite population of pericytes and adventitial progenitor cells (APCs). Those factors that promote the differentiation of PSC into bone or fat cell types are not well understood. Here, we observed high expression of WISP-1 among human PSC in vivo, after purification, and upon transplantation in a bone defect. Next, modulation of WISP-1 expression was performed, using WISP-1 overexpression, WISP-1 protein, or WISP-1 siRNA. Results demonstrated that WISP-1 is expressed in the perivascular niche, and high expression is maintained after purification of PSC, and upon transplantation in a bone microenvironment. In vitro studies demonstrate that WISP-1 has pro-osteogenic/anti-adipocytic effects in human PSC, and that regulation of BMP signaling activity may underlie these effects. In summary, our results demonstrate the importance of the matricellular protein WISP-1 in regulation of the differentiation of human stem cell types within the perivascular niche. WISP-1 signaling upregulation may be of future benefit in cell therapy mediated bone tissue engineering, for the healing of bone defects or other orthopaedic applications.

Assessment of muscle Longissimus thoracis et lumborum marbling by image analysis and relationships between meat quality parameters.

The intramuscular fat (IMF), recognized by the consumer as marbling, is an important meat quality trait. The objective of this study was to validate a new method of beef marbling evaluation by image analysis. The new assessment was compared with two known marbling measurements: chemical IMF and USDA scores. Moreover, the relationship between marbling measurements and other meat quality parameters was investigated. Samples of Longissimus thoracis et lumborum (LTL) muscle were obtained from carcasses of 39 Italian crossbred heifers and 62 Angus bred heifers, that underwent two different dietary treatments. The use of various breeds and diets was chosen to obtain different intramuscular fat levels, in order to validate the use of Image J software for the analysis of different type of beef meat. The images of fresh cuts were appraised by experienced beef graders, and the samples were used to determine fat content by chemical Soxhlet extraction. Carcasses measurements according to the EUROP system, and other physical meat proprieties were also assessed. The results demonstrated that the marbling measurements obtained by computer image analysis, such as the number of marbling particles, the average particle size (mm), and the percentage of marbling particles (%), significantly (P < 0.05) correlated with USDA scores and IMF content. Moreover, the principal component analysis (PCA) showed three principal meat components, identified as 1) color, 2) fat, and 3) water release. The second principal component (PC) explained 24.94% of variance, and was positively correlated with image analysis measures, USDA score, and IMF, while negatively correlated with the Warner-Bratzler shear force (WBSF).

Alaska Mountain Wilderness Ski Classic: Alterations in Caloric Expenditure and Body Composition.

INTRODUCTION: The Alaska Mountain Wilderness Ski Classic is a self-supported ultramarathon cross-country skiing event that traverses one of the mountain ranges of Alaska each winter. Unique aspects of this event challenge athletes with a significant amount of physical and mental stress while in the chronically cold conditions of the Arctic. Assessment of energy requirements or body composition has never been performed during this event. The objective of the study was to evaluate the influence of the 2016 Alaska Mountain Wilderness Ski Classic on caloric expenditure and body composition. METHODS: Caloric expenditure was estimated using GT3x+ Actigraph accelerometers and ActiLife software. Lean tissue mass, total fat mass, visceral fat mass, and bone mineral density were measured using a General Electric iDXA before and after the event. Data are presented as mean±SD. Differences were analyzed using paired t tests with significance at P<0.05. RESULTS: Fifteen participants (age=32.7±6.6 years, body mass index=23.7±2.3 kg·m2) completed the study, 8 males and 7 females. Caloric expenditure was 6238±1390 kcal·day-1, and 37,163±8425 kcal for the entire event. Fat mass was reduced from pre-event (∆1.3±0.7 kg, P=0.00003). There was an increase in lean tissue mass (∆1.7±1.3 kg, P=0.0003) and relative skeletal muscle index (∆0.2±0.2 kg·m², P=0.001). There was no change in bone mineral density (∆0±0 g·cm3, P=0.4). CONCLUSIONS: Despite the metabolic demands, fat mass was reduced and lean tissue mass was preserved. Future studies of this event should be directed toward assessment of the nutritional provisions utilized and the mechanisms responsible for the preservation of lean tissue mass.