Influence of probe position in the measurement of muscle thickness and its association with lean mass: an ultrasound study / Influencia de la posición de la sonda en la medición del grosor muscular y su asociación con la masa magra: un estudio ecográfico

SUMMARY: Skeletal muscles play a fundamental role in people's lives and their evaluation provides significant information on health. Different tools have been used to evaluate muscle mass, and the evaluation of muscle thickness (MT) using ultrasound has been included as an alternative, which can be performed with the probe in different positions; however, these could present differences. The objectives of this study were to determine whether there are differences in the measurement of MT in the vastus lateralis (VL) muscle using the probe in the longitudinal or transverse position, and to determine its association with the lean mass of the lower limbs. The results indicated no significant differences between MT measurements with the probe in the longitudinal and transverse positions (p =0.084). However, when associating these measurements with lower limb lean mass, it was found that transverse measurements had a strong association (r =0.547; p < 0.001), while longitudinal measurements had a moderate association (r =0.351; p =0.007). This suggests that measurements with the probe positioned transversely to measure the MT would be the best option. Therefore, it could be useful as an indicator of lower limb lean mass in the absence of tools, such as bioelectrical bioimpedance or magnetic nuclear resonance.

El músculo esquelético cumple un rol fundamental en la vida de las personas, y su evaluación entrega mucha información de la salud. Se han utilizado diferentes herramientas para evaluar la masa muscular, y el último tiempo se ha incluido la evaluación del grosor muscular (MT) a través de la ecografía como una alternativa para estimarla, las cuales se pueden realizar con la sonda en distintas posiciones, sin embargo, estas podrían presentar diferencias. Los objetivos del estudio fueron determinar si existen diferencias en la medición de MT en el músculo vasto lateral (VL) utilizando la sonda en posición longitudinal o transversal y determinar su asociación con la masa magra de los miembros inferiores. Los resultados indican que no existen diferencias significativas entre las mediciones de MT con la sonda en posición longitudinal y transversal (valor p: 0.084). Sin embargo, al asociar estas mediciones con la masa magra de los miembros inferiores, se encontró que las mediciones transversales poseen una asociación fuerte (r: 0.547; valor p < 0.001), mientras que las mediciones longitudinales presentan una asociación moderada (r: 0.351; valor p: 0.007). Esto sugiere que las mediciones con la sonda posicionada transversal para medir MT serían la mejor opción. Por lo tanto, podría ser de utilidad como un indicador de masa magra de los miembros inferiores en caso de no contar con herramientas como la bioimpedancia bioeléctrica o resonancia nuclear magnética.

Genetic association between feed efficiency, growth, scrotal circumference, and carcass traits in Guzerat cattle.

The objective of this study was to estimate the genetic parameters for feed efficiency-related traits and their genetic correlations with growth, male fertility, and carcass traits using multi-trait analysis in Guzerat cattle. Further, it aimed to predict the direct and correlated responses for feed efficiency traits when selection was applied for growth, male fertility, and carcass traits. The evaluated traits were adjusted weight at 120 (W120), 210 (W210), 365 (W365), and 450 days of age (W450), adjusted scrotal circumference at 365 days of age (SC365) and at 450 days of age (SC450), scrotal circumference, ribeye area (REA), backfat thickness (BFT), rump fat thickness (RFT), residual feed intake (RFI), and dry matter intake (DMI). The genetic parameters were obtained by the restricted maximum likelihood method (REML), using an animal model in multi-trait analyses. The heritability estimates for W120, W210, W365, W450, SC365, and SC450 varied from low to high (0.17 to 0.39). The carcass traits, REA, BFT, and RFT, displayed low to moderate heritability estimates, 0.27, 0.10, and 0.31, respectively. The heritability estimates for RFI (0.15) and DMI (0.23) were low and moderate, respectively. The RFI showed low genetic correlations with growth traits, ranging from - 0.07 to 0.22, from 0.03 to 0.05 for scrotal circumference, and from - 0.35 to 0.16 for carcass, except for DMI, which ranged from 0.42 to 0.46. The RFI and DMI presented enough additive genetic variability to be used as selection criteria in Guzerat breed genetic improvement program. Additionally, the response to selection for RFI would be higher when selection is performed directly for this trait. The selection for residual feed intake would not promote unfavorable correlated responses for scrotal circumference, carcass (yield and finish), and growth traits. Therefore, the selection for more efficient animals would not compromise the productive, reproductive, and carcass performance, contributing to reduce the production costs, increasing the profitability and sustainability of beef cattle production in tropical areas.

The Anatomy Study of Temporal Region based on Ultrasound Investigation: A Spatial Structure Study.

BACKGROUND: With the growing popularity of rejuvenation, people are giving more concerns on their temporal depression which makes them look older and wishing to improve it by injection. The complex structure of the temporal region leads to a higher risk of failed injection. The temporal region is well understood based on cadaver anatomy, but few studies have described its spatial structure. The purpose of this study was to improve the efficacy and safety of temporal injection by studying the spatial structure of the soft tissues and major blood vessels in each layer of the temporal region. METHODS: A total of 30 volunteers (24 men and 6 women, 60 temporal regions) were investigated. Color Doppler ultrasound was used to measure the thickness of the temporal layers at the selected measurement points (A, B, C, D, E, and F). The maximum thickness of the temporal fat pads was also measured, and the layers, depths and diameters of the major temporal vessels (frontal branch of superficial temporal artery and vein, middle temporal vein and deep temporal artery) were measured. RESULTS: At the various measurement points, the thickness and position of the skin, subcutaneous fat superficial fascia, and temporalis muscle did not differ significantly, whereas the superficial temporal fat pad and deep temporal fat pad differed significantly. The diameter and depth of the superficial temporal artery, superficial temporal vein, and deep temporal artery did not differ significantly, whereas the diameter of the middle temporal vein differed slightly, whereas the depth differed more obviously. CONCLUSIONS: The temporal structure is very complex, and understanding the spatial position of each layer of tissue plays an important role in improving the efficacy and safety of temporal filler injection. Ultrasound can help us to understand this information and assist in therapy. LEVEL OF EVIDENCE: Level II.

The equine patellar ligaments and the infrapatellar fat pad - a microanatomical study.

BACKGROUND: Interpretation of patellar ligament (PL) ultrasonography may be difficult, as hypoechoic or heterogenous echogenicity are common findings. Verifying suspected disease of equine PLs by histopathology is also problematic as descriptions of normal PL vascularity and histology are scarce. The current study describes the PL and infrapatellar fat pad (IFP) vascular pattern from computed tomography scans of barium perfused normal equine specimens (n = 8; age 10 days to 18 years), as well as routine histology to serve as a reference for future investigations into PL pathology and IFP disease. RESULTS: The PLs received a bipolar blood supply. Vascular architecture consisted of numerous distinct longitudinal vessels with several horizontal connections, which branched into extensive latticeworks of smaller vessels throughout the ligaments. Several vascular connections between the PLs and the IFP were identified. One distinct longitudinal vessel was seen entering each of the IFP lobes at the distocranial aspect, branching extensively into lobar vascular networks which anastomosed by several horizontal branches at the mid portion of the IFP where the two lobes merge. Histologically, there were large variations in PL interfascicular endotenon thickness, vascularity and fatty infiltration; these parameters increased with age for the intermediate and medial PL. Areas of metaplastic tenocytes / chondroid metaplasia were identified in all investigated adult medial PLs; in 2/7 in the intermediate PL and in 4/7 in the lateral PL. The adult IFP consisted of white unilocular adipose tissue, organized in lobules separated by thin connective tissue septa increasing in thickness towards the periphery and the distocentral aspect. CONCLUSIONS: The equine PLs and IFP are highly vascularized structures with ample vascular connections suggestive of crosstalk. This, together with the large variation in PL endotenon thickness, vascularity and fatty infiltration, should be taken into consideration when assessing potential PL histopathology as these changes increase with age and are found in horses without clinical signs of stifle disease. Metaplastic tenocytes / chondroid metaplasia should be considered a normal finding throughout the medial PL and is not age dependent. The role of the equine IFP in stifle disease has yet to be elucidated.

Differences in histomorphology and expression of key lipid regulated genes of four adipose tissues from Tibetan pigs.

Tibetan pigs, an indigenous pig breed in China, have high overall fat deposition and flavorful and tasty meat. They are thus good models for studying adipogenesis. Few studies have been conducted focusing on expression of lipid regulated genes in different adipose tissues of Tibetan pigs. Therefore, we compared the difference of histomorphology and expression level of lipid regulated genes through qPCR and western blot in subcutaneous fat, perirenal fat, omental adipose tissue, and inguinal fat of Tibetan pigs. Our results showed that the area of subcutaneous adipocytes in Tibetan pigs was smaller, while the other three adipose tissues (perirenal fat, greater omentum fat, inguinal fat) had cell areas of similar size. The gene expression of FABP4, FASN, FABP3, and ME1 in subcutaneous fat was significantly higher than that in perirenal fat. Furthermore, the protein expression of FABP4 was significantly lower in subcutaneous fat than in perirenal fat (p < 0.05), and the expression of FASN was higher in greater omentum fat than in subcutaneous fat (p = 0.084). The difference in adipocyte cell size and expression of lipid-regulated genes in adipose tissues from the various parts of the pig body is likely due to the different cellular lipid metabolic processes. Specially, FABP4 and FASN may be involved in the regulation of fat deposition in different adipose tissues of Tibetan pigs.

Qualitative and quantitative characteristics of the passive compartment underneath the myocardial bridge comprising the blood vessel adventitia and the perivascular connective tissue / Características cualitativas y cuantitativas del compartimento pasivo debajo del puente miocárdico que comprende la adventicia del vaso sanguíneo y el tejido conectivo perivascular

SUMMARY: Myocardial bridges are inborn anomalies frequently found in authopsies. Although tipically clinically silent, they are occasionally associated with severe clinical manifestations, e.g. myocardial ischemia or even sudden death. The pathophysiology and risk factors for these manifestations have not yet been completely elucidated. The connective tissue underneath the bridge has been considered as one of the factors the symptoms depend on. Thus, the aim of this research was to determine the histological characteristics of the connective tissue lying underneath the myocardial bridge and to contribute to a better understanding of the protective effects this passive compartment might have in prevention of severe clinical manifestations of myocardial bridging. The study was carried out on twenty hearts with myocardial bridges. Length of the bridge was determined using a precise electronic caliper. Sections of the myocardial bridges with the underlying connective tissue were obtained and prepared for qualitative and quantitative analysis. The connective tissue underneath the bridges was composed of adipose tissue and loose connective tissue in different ratios. The tissue underneath thin bridges was predominantly composed of adipose tissue, while loose connective tissue was the dominant component under thick bridges. The myocardial bridges had an average thickness of 0,98 ± 0.44 mm and an average length of 15,25±5,65 mm. We found a strong positive correlation between the myocardial bridge thickness and length (r = 0,860, p = 0,0001). The thickness of the passive connective tissue compartment under the myocardial bridges was 0,58±0,22 mm, and there was no correlation between this parameter and the myocardial bridge thickness (r = -0,011; p = 0,963). In the clinical evaluation of patients with these anomalies it is necessary to take into account independently the myocardial bridge thickness and length on one side and the thickness of the connective tissue lying underneath it on the other.

Los puentes miocárdicos son anomalías congénitas que se encuentran con frecuencia en las autopsias. Aunque típicamente éstos son clínicamente silenciosos, ocasionalmente se asocian con manifestaciones clínicas graves, como isquemia miocárdica o incluso muerte súbita. La fisiopatología y los factores de riesgo de estas manifestaciones aún no se han dilucidado por completo. El tejido conectivo debajo del puente se ha considerado como uno de los factores de los que dependen los síntomas. Por lo tanto, el objetivo de esta investigación fue determinar las características histológicas del tejido conectivo que se encuentra debajo del puente miocárdico y contribuir a una mejor comprensión de los efectos protectores que este compartimento pasivo podría tener en la prevención de manifestaciones clínicas graves de puente miocárdico. El estudio se llevó a cabo en veinte corazones con puentes miocárdicos. La longitud del puente se determinó utilizando un calibrador electrónico preciso. Se obtuvieron secciones de los puentes miocárdicos con el tejido conjuntivo subyacente y se prepararon para análisis cualitativo y cuantitativo. El tejido conectivo debajo de los puentes estaba compuesto de tejido adiposo y tejido conectivo laxo en diferentes proporciones. El tejido debajo de los puentes delgados estaba predominantemente compuesto de tejido adiposo, mientras que el tejido conectivo laxo era el componente dominante debajo de los puentes gruesos. Los puentes de miocardio tenían un espesor promedio de 0,98 ± 0,44 mm y una longitud promedio de 15,25 ± 5,65 mm. Encontramos una fuerte correlación positiva entre el grosor y la longitud del puente miocárdico (r = 0,860, p = 0,0001). El grosor del compartimiento de tejido conectivo pasivo debajo de los puentes miocárdicos era de 0,58±0,22 mm, y no hubo correlación entre este parámetro y el grosor del puente miocárdico (r = -0,011; p = 0,963). En la evaluación clínica de pacientes con estas anomalías es necesario tener en consideración de forma independiente el grosor y la longitud del puente de miocardio por un lado y el grosor del tejido conectivo que se encuentra debajo del mismo por el otro.

Morphological characteristics of the infrapatellar fat pad.

The relationship between the morphological characteristics of the infrapatellar fat pad (IFP) and joint deformity has yet to be fully elucidated. Therefore, the purpose of this study was to clarify the morphological characteristics of the IFP and to identify the relationships between morphological characteristics of the IFP and degenerative grade of the articular surface of the patella. This investigation examined 41 legs from 25 Japanese cadavers. The IFP length, width, and volume were measured. It was categorized into three types: Type I, IFP proximal located on medial and lateral sides of the patella; Type II, the IFP proximal only located medially; and Type III, absence of the IFP proximal. Articular surfaces were graded as macroscopically intact or mildly altered (Grade I), moderately (Grade II), or severely (Grade III). Grade III was significantly more frequent than Grades I or II in Type III. IFP volume was significantly larger in Type I than in Types II or III. A negative correlation was found between the degenerative grade of the articular surface of the patella and IFP volume. It was suggested that a relationship between the degenerative grade of the articular surface of the patella and the IFP volume.

Midface Multilayering Filler Injection Technique: Understanding of the Dynamic Facial Anatomy Through a "Smiling Cadavers" Anatomical Study.

BACKGROUND: Understanding age-related changes in compartmentalized facial fat and their role in facial dynamics and aesthetics is essential to target filler injections for midface rejuvenation. METHODS: A novel anatomical approach ("smiling cadavers") was used to identify the main midface fat compartments involved during muscular contraction when smiling and their motion and behavior with and without filler injections. Based on these insights and the literature, a multilayering filler injection approach was developed to optimize midface rejuvenation by restoring fat volumes using rheologically different products injected into different fat compartments. RESULTS: Twenty-four hemifacial dissections confirmed the presence of two fat compartment layers, separated by the orbicularis oculi muscle in the horizontal plane and by the septa in the vertical plane, and revealed the anatomical effects of facial movement. The midface is composed of deep static fat compartments and a superficial dynamic adipose layer that follows the facial movements, creating a natural dynamic appearance. A proof-of-concept study involved 130 White patients (36 to 56 years; 91 percent women). After the procedure, 95 percent of patients and 98 percent of practitioners rated facial appearance as "improved" or "much/very much improved." No major complications were reported. CONCLUSIONS: The smiling cadavers method enhances understanding of dynamic facial anatomy by showing the superficial and deep fat compartments of the midface at rest and their motion during a procedure to represent a smile. The multilayered injection technique takes into account these anatomical findings to rejuvenate the midface, achieving a natural appearance at rest and during motion.

Deep learning segmentation and quantification method for assessing epicardial adipose tissue in CT calcium score scans.

Epicardial adipose tissue volume (EAT) has been linked to coronary artery disease and the risk of major adverse cardiac events. As manual quantification of EAT is time-consuming, requires specialized training, and is prone to human error, we developed a deep learning method (DeepFat) for the automatic assessment of EAT on non-contrast low-dose CT calcium score images. Our DeepFat intuitively segmented the tissue enclosed by the pericardial sac on axial slices, using two preprocessing steps. First, we applied a HU-attention-window with a window/level 350/40-HU to draw attention to the sac and reduce numerical errors. Second, we applied a novel look ahead slab-of-slices with bisection ("bisect") in which we split the heart into halves and sequenced the lower half from bottom-to-middle and the upper half from top-to-middle, thereby presenting an always increasing curvature of the sac to the network. EAT volume was obtained by thresholding voxels within the sac in the fat window (- 190/- 30-HU). Compared to manual segmentation, our algorithm gave excellent results with volume Dice = 88.52% ± 3.3, slice Dice = 87.70% ± 7.5, EAT error = 0.5% ± 8.1, and R = 98.52% (p < 0.001). HU-attention-window and bisect improved Dice volume scores by 0.49% and 3.2% absolute, respectively. Variability between analysts was comparable to variability with DeepFat. Results compared favorably to those of previous publications.

Proposal of a normative table for classification of body fat percentage in Brazilian jiu-jitsu athletes / Propuesta de tabla normativa para la clasificación del porcentaje de grasa corporal en atletas de jiu-jitsu brasileño

SUMMARY: Previous evidence indicates that body fat can distinguish Brazilian jiu-jitsu (BJJ) athletes according to the competitive level. However, propositions of cut-off points for establishing classifications of body fat percentage for combat sports athletes and, specifically, for BJJ athletes are still incipient in the literature. In this sense, the main aim of the present study was to establish a normative table for the classification of body fat percentage in BJJ athletes. As a secondary aim, athletes were compared according to competitive level. Ninety male BJJ athletes (aged: 29.0 ± 8.2 years; practice time: 6.0 ± 2.1 years; body mass: 82.1 ± 12.7 kg; height: 175.9 ± 6.5 cm; fat mass: 16.0 ± 8.9 kg; bone mineral content: 3.7 ± 0.6 kg; muscle mass: 37.9 ± 5.4 kg; body fat percentage: 17.3 ± 6.8 %; basal metabolic rate: 1811.4 ± 193.4 kcal) from different competitive levels: state (n= 42), national (n= 26) and international (n= 22) took part in this study. All athletes had their body composition measured via tetrapolar bioelectrical impedance. Percentiles p10, p25, p50, p75, and p90 were used to establish the classification. As a result, the following classification was obtained: <7.7 % (very low); ≥7.7-11.5 % (low); 11.6-17.0 % (medium); 17.1-24.0 % (high) and ≥24.1 % (very high). State-level athletes had a higher fat percentage than national and international-level athletes (p<0.05). The proposed cut-off points can help professionals responsible for sports training and nutritional prescription in monitoring the body fat of BJJ athletes.

RESUMEN: La grasa corporal puede distinguir a los atletas de jiu-jitsu brasileño (BJJ) según el nivel competitivo. Sin embargo, las propuestas de puntos de corte para establecer clasificaciones de porcentaje de grasa corporal para deportistas de deportes de combate y, específicamente, para deportistas de BJJ son aún incipientes en la literatura. En este sentido, el objetivo principal del presente estudio fue establecer una tabla normativa para la clasificación del porcentaje de grasa corporal en atletas de BJJ. Secundariamente, comparar a los deportistas según el nivel competitivo. Participaron noventa atletas masculinos de BJJ (edad: 29,0 ± 8,2 años; tiempo de práctica: 6,0 ± 2,1 años; masa corporal: 82,1 ± 12,7 kg; estatura: 175,9 ± 6,5 cm; masa adiposa: 16,0 ± 8,9 kg; contenido mineral óseo: 3,7 ± 0,6 kg; masa muscular: 37,9 ± 5,4 kg; porcentaje de grasa corporal: 17,3 ± 6,8 %; tasa metabólica basal: 1811,4 ± 193,4 kcal) de diferentes niveles competitivos: estatal (n= 42), nacional (n= 26) e internacional (n= 22). Se evaluó la composición corporal a través de bioimpedancia tetrapolar. Para establecer la clasificación se utilizaron los percentiles p10, p25, p50, p75 y p90. Como resultado se obtuvo la siguiente clasificación: <7,7 % (muy bajo); ≥7,7-11,5 % (bajo); 11,6-17,0 % (medio); 17,1-24,0 % (alto) y ≥24,1 % (muy alto). Los atletas de nivel estatal tenían un porcentaje de grasa corporal más alto respecto a los atletas de nivel nacional e internacional (p <0.05). Los puntos de corte propuestos pueden ser útiles para monitorizar la grasa corporal de los atletas de BJJ.

Joint Association of Metabolic Health and Obesity with Ten-Year Risk of Cardiovascular Disease among Chinese Adults.

OBJECTIVE: This study aims to investigate the association of metabolic phenotypes that are jointly determined by body mass index (BMI) or fat mass percentage and metabolic health status with the ten-year risk of cardiovascular disease (CVD) among Chinese adults. METHODS: Data were obtained from a cross-sectional study. BMI and body fat mass percentage (FMP) combined with the metabolic status were used to define metabolic phenotypes. Multiple linear regression and logistic regression were used to examine the effects of metabolic phenotypes on CVD risk. RESULTS: A total of 13,239 adults aged 34-75 years were included in this study. Compared with the metabolically healthy non-obese (MHNO) phenotype, the metabolically unhealthy non-obese (MUNO) and metabolically unhealthy obese (MUO) phenotypes defined by BMI showed a higher CVD risk [odds ratio, OR (95% confidence interval, CI): 2.34 (1.89-2.89), 3.45 (2.50-4.75), respectively], after adjusting for the covariates. The MUNO and MUO phenotypes defined by FMP showed a higher CVD risk [ OR (95% CI): 2.31 (1.85-2.88), 2.63 (1.98-3.48), respectively] than the MHNO phenotype. The metabolically healthy obese phenotype, regardless of being defined by BMI or FMP, showed no CVD risk compared with the MHNO phenotype. CONCLUSION: General obesity without central obesity does not increase CVD risk in metabolically healthy individuals. FMP might be a more meaningful factor for the evaluation of the association of obesity with CVD risk. Obesity and metabolic status have a synergistic effect on CVD risk.

The multifaceted functions of the Fat mass and Obesity-associated protein (FTO) in normal and cancer cells.

The last decade has seen mRNA modification emerge as a new layer of gene expression regulation. The Fat mass and obesity-associated protein (FTO) was the first identified eraser of N6-methyladenosine (m6A) adducts, the most widespread modification in eukaryotic messenger RNA. This discovery, of a reversible and dynamic RNA modification, aided by recent technological advances in RNA mass spectrometry and sequencing has led to the birth of the field of epitranscriptomics. FTO crystallized much of the attention of epitranscriptomics researchers and resulted in the publication of numerous, yet contradictory, studies describing the regulatory role of FTO in gene expression and central biological processes. These incongruities may be explained by a wide spectrum of FTO substrates and RNA sequence preferences: FTO binds multiple RNA species (mRNA, snRNA and tRNA) and can demethylate internal m6A in mRNA and snRNA, N6,2'-O-dimethyladenosine (m6Am) adjacent to the mRNA cap, and N1-methyladenosine (m1A) in tRNA. Here, we review current knowledge related to FTO function in healthy and cancer cells. In particular, we emphasize the divergent role(s) attributed to FTO in different tissues and subcellular and molecular contexts.

Reevaluation of the Layered Anatomy of the Forehead: Introducing the Subfrontalis Fascia and the Retrofrontalis Fat Compartments.

BACKGROUND: Novel imaging methods have provided new insights into the layered anatomy of the forehead. This study seeks to critically reevaluate the layered anatomy of the forehead by using ultrasound imaging and cadaveric dissection to provide an accurate anatomical description that can be used to guide safer surgical and minimally invasive frontal procedures. METHODS: This study used ultrasound imaging in a sample of 20 volunteers (12 female and eight male volunteers; aged 35.25 ± 4.2 years; body mass index, 24.28 ± 3.5 kg/m2) and cadaveric dissections of 16 body donors (12 female and four male body donors; aged 72.76 ± 9.5 years) to reevaluate the layered anatomy of the forehead. Layer-by-layer dissections and ultrasound-based measurements of the frontal structures guided conclusions. RESULTS: The following layered arrangement was identified: layer 1, skin; layer 2, superficial fatty layer; layer 3, suprafrontalis fascia; layer 4, orbicularis oculi and frontalis muscle (same plane); layer 5, a homogenous layer of fat [preseptal fat (in the upper eyelid), retro-orbicularis fat (deep to the orbicularis oculi muscle), and retro-frontalis fat (deep to the frontalis muscle); layer 6, subfrontalis fascia; layer 7, preperiosteal fat within the prefrontal space in the lower forehead and deep compartments in the upper forehead; and layer 8, periosteum. CONCLUSIONS: The results of this study add to the current understanding of the layered arrangement of the forehead. The combination of ultrasound imaging and cadaveric dissections provided evidence for a continuous fatty layer deep to the frontalis muscle.

Reference values for volume, fat content and shape of the hip abductor muscles in healthy individuals from Dixon MRI.

Healthy hip abductor muscles are a good indicator of a healthy hip and an active lifestyle, as they are greatly involved in human daily activities. Fatty infiltration and muscle atrophy are associated with loss of strength, loss of mobility and hip disease. However, these variables have not been widely studied in this muscle group. We aimed to characterize the hip abductor muscles in a group of healthy individuals to establish reference values for volume, intramuscular fat content and shape of this muscle group. To achieve this, we executed a cross-sectional study using Dixon MRI scans of 51 healthy subjects. We used an automated segmentation method to label GMAX, GMED, GMIN and TFL muscles, measured normalized volume (NV) using lean body mass, fat fraction (FF) and lean muscle volume for each subject and computed non-parametric statistics for each variable grouped by sex and age. We measured these variables for each axial slice and created cross-sectional area and FF axial profiles for each muscle. Finally, we generated sex-specific atlases with FF statistical images. We measured median (IQR) NV values of 12.6 (10.8-13.8), 6.3 (5.6-6.7), 1.6 (1.4-1.7) and 0.8 (0.6-1.0) cm3 /kg for GMAX, GMED, GMIN and TFL, and median (IQR) FF values of 12.3 (10.1-15.9)%, 9.8 (8.6-11.2)%, 10.0 (9.0-12.0)% and 10.2 (7.8-13.5)% respectively. FF values were significantly higher for females for the four muscles (p < 0.01), but there were no significant differences between the two age groups. When comparing individual muscles, we observed a significantly higher FF in GMAX than in the other muscles. The reported novel reference values and axial profiles for volume and FF of the hip abductors, together with male and female atlases, are tools that could potentially help to quantify and detect early the deteriorating effects of hip disease or sarcopenia.

Visual Image Analysis for a new classification method of bovine carcasses according to EU legislation criteria.

In the European Community, conformation and fat cover of bovine carcasses is assessed using the SEUROP grading system. In this study we pursued the development of an application software (App) based on Visual Image Analysis, useful for SEUROP and Fat Cover grading of bovine carcasses using a smartphone. The App was trained using 500 bovine carcasses. Carcass conformation and Fat Cover classes were assessed in parallel by expert evaluators and by App. Overall, a high correspondence was found between the measurements of carcasses parameters by operators and by the App, as high as 84.2% for SEUROP and 86.4% for the Fat Cover. In the 15.8% of samples with discordant SEUROP evaluation, and in the 13.6% of samples with discordant Fat Cover evaluation, the operators' and App measurements deviated by only one class. All values also aligned with the requirements expected by the current legislation for the use of automated and/or semi-automated systems able to determine the market value of carcasses.

Discriminatory capacity of obesity indicators as predictors of high liver fat in US adolescents.

BACKGROUND: The aims of this study were to assess the potential of 16 anthropometric, body composition and endocrine indexes as predictors of high liver fat and determine the most appropriate cut-off points in US adolescents. METHODS: A cross-sectional study was conducted on a population of 816 adolescents aged 12-17 years. The FibroScan® 502V2 device was used to estimate the controlled attenuation parameter (CAP). Body fat percentage, fat mass, trunk fat percentage and trunk fat mass were measured by dual-energy X-ray absorptiometry. Anthropometric data and metabolic parameters were determined. Receiver operating characteristic curves were analysed to estimate the optimal cut-off points that best identify adolescents with high liver fat (CAP ≥90th percentile). RESULTS: In boys, triponderal mass index (TMI) had the highest area under curve (AUC) value (0.865) and the optimal cut-off score for TMI was 17.47 kg/m3 , which had 81.32 sensitivity and 82.99 specificity. In girls, trunk fat index (TFI) had the highest AUC value (0.826) and its optimal cut-off score in screening for high liver fat was 3.76 kg/m2 , which had 74.04 sensitivity and 88.03 specificity. Fat mass index (FMI) index had the second highest AUC values (0.863 in boys 0.812 in girls) in both sex; the cut-off point for the detection of high liver fat was <8.66 kg/m2 for girls and <7.45 kg/m2 for boys. CONCLUSION: Assessment of TMI in boys, TFI in girls, and FMI in both sexes are low-cost and easy-to-use parameters that may be useful as early screening tools for possible high liver fat in adolescents.

Joint Association of Metabolic Health and Obesity with Ten-Year Risk of Cardiovascular Disease among Chinese Adults / 生物医学与环境科学（英文）

OBJECTIVE@#This study aims to investigate the association of metabolic phenotypes that are jointly determined by body mass index (BMI) or fat mass percentage and metabolic health status with the ten-year risk of cardiovascular disease (CVD) among Chinese adults.@*METHODS@#Data were obtained from a cross-sectional study. BMI and body fat mass percentage (FMP) combined with the metabolic status were used to define metabolic phenotypes. Multiple linear regression and logistic regression were used to examine the effects of metabolic phenotypes on CVD risk.@*RESULTS@#A total of 13,239 adults aged 34-75 years were included in this study. Compared with the metabolically healthy non-obese (MHNO) phenotype, the metabolically unhealthy non-obese (MUNO) and metabolically unhealthy obese (MUO) phenotypes defined by BMI showed a higher CVD risk [odds ratio, OR (95% confidence interval, CI): 2.34 (1.89-2.89), 3.45 (2.50-4.75), respectively], after adjusting for the covariates. The MUNO and MUO phenotypes defined by FMP showed a higher CVD risk [ OR (95% CI): 2.31 (1.85-2.88), 2.63 (1.98-3.48), respectively] than the MHNO phenotype. The metabolically healthy obese phenotype, regardless of being defined by BMI or FMP, showed no CVD risk compared with the MHNO phenotype.@*CONCLUSION@#General obesity without central obesity does not increase CVD risk in metabolically healthy individuals. FMP might be a more meaningful factor for the evaluation of the association of obesity with CVD risk. Obesity and metabolic status have a synergistic effect on CVD risk.

Mice as an animal model for the study of adipose tissue and obesity / Ratones como modelo animal para el estudio del tejido adiposo y la obesidad

SUMMARY: The study of adipose tissue has gained increasing importance in the biomedical area due to its implications for health and obesity. Obesity is a situation of great concern mainly in the Western world due to its high prevalence and morbidity. Experimental studies on obesity often need a model where it is possible to carry out experiments, drug testing, and other therapeutic procedures, which are typically not possible in humans. Although several animals are used for obesity studies, rodents are by far the most used animals, and among rodents, mice are particularly indicated for this investigation. This mini review will introduce the challenging classification of obesity in rodents, paralleling human obesity, defining and classifying what an obese mouse is. The text will differentiate between white adipose tissue (WAT, aimed at endocrine secretion and lipogenesis) and brown adipose tissue (BAT, aimed at thermogenesis) and describe the browning process of white adipocytes in an adaptation to increase thermogenesis. The text will also describe the various types of body fat in mice with their differences and indications for investigation and teach how to recognize and dissect these fats. At the end of this introductory reading, the young researcher is expected to have acquired sufficient knowledge to start an experimental investigative project on obesity.

RESUMEN: El estudio del tejido adiposo ha ganado una importancia creciente en el área biomédica por sus implicaciones para la salud y la obesidad. La obesidad es una situación de gran preocupación, principalmente, en el mundo occidental debido a su alta prevalencia y morbilidad. Los estudios experimentales sobre la obesidad a menudo necesitan un modelo en el que sea posible realizar experimentos, pruebas de drogas y otros procedimientos terapéuticos, que normalmente no son posibles en humanos. Aunque se utilizan varios animales para estudios de obesidad, los roedores son, con mucho, los animales más utilizados y, entre los roedores, los ratones están especialmente indicados para esta investigación. Esta mini revisión presenta la desafiante clasificación de la obesidad en roedores, en paralelo con la obesidad humana, definiendo y clasificando qué es un ratón obeso. El texto diferencia entre tejido adiposo blanco (WAT, destinado a la secreción endocrina y lipogénesis) y tejido adiposo marrón (BAT, destinado a la termogénesis) y describe el proceso de pardeamiento de los adipocitos blancos en una adaptación para aumentar la termogénesis. El texto también describe los diversos tipos de grasa corporal en ratones con sus diferencias e indicaciones para la investigación y enseña cómo reconocer y diseccionar estas grasas. Al final de esta lectura introductoria, se espera que el joven investigador haya adquirido los conocimientos suficientes para iniciar un proyecto de investigación experimental sobre la obesidad.