Reverse Scan Conversion and Efficient Deep Learning Network Architecture for Ultrasound Imaging on a Mobile Device.

Point-of-care ultrasound (POCUS), realized by recent developments in portable ultrasound imaging systems for prompt diagnosis and treatment, has become a major tool in accidents or emergencies. Concomitantly, the number of untrained/unskilled staff not familiar with the operation of the ultrasound system for diagnosis is increasing. By providing an imaging guide to assist clinical decisions and support diagnosis, the risk brought by inexperienced users can be managed. Recently, deep learning has been employed to guide users in ultrasound scanning and diagnosis. However, in a cloud-based ultrasonic artificial intelligence system, the use of POCUS is limited due to information security, network integrity, and significant energy consumption. To address this, we propose (1) a structure that simultaneously provides ultrasound imaging and a mobile device-based ultrasound image guide using deep learning, and (2) a reverse scan conversion (RSC) method for building an ultrasound training dataset to increase the accuracy of the deep learning model. Experimental results show that the proposed structure can achieve ultrasound imaging and deep learning simultaneously at a maximum rate of 42.9 frames per second, and that the RSC method improves the image classification accuracy by more than 3%.

The effects of whey, pea, and collagen protein supplementation beyond the recommended dietary allowance on integrated myofibrillar protein synthetic rates in older males: a randomized controlled trial.

BACKGROUND: Skeletal muscle mass is determined predominantly by feeding-induced and activity-induced fluctuations in muscle protein synthesis (MPS). Older individuals display a diminished MPS response to protein ingestion, referred to as age-related anabolic resistance, which contributes to the progression of age-related muscle loss known as sarcopenia. OBJECTIVES: We aimed to determine the impact of consuming higher-quality compared with lower-quality protein supplements above the recommended dietary allowance (RDA) on integrated MPS rates. We hypothesized that increasing total protein intake above the RDA, regardless of the source, would support higher integrated rates of myofibrillar protein synthesis. METHODS: Thirty-one healthy older males (72 ± 4 y) consumed a controlled diet with protein intake set at the RDA: control phase (days 1-7). In a double-blind, randomized controlled fashion, participants were assigned to consume an additional 50 g (2 × 25g) of whey (n = 10), pea (n = 11), or collagen (n = 10) protein each day (25 g at breakfast and lunch) during the supplemental phase (days 8-15). Deuterated water ingestion and muscle biopsies assessed integrated MPS and acute anabolic signaling. Postprandial blood samples were collected to determine feeding-induced aminoacidemia. RESULTS: Integrated MPS was increased during supplemental with whey (1.59 ± 0.11 %/d; P < 0.001) and pea (1.59 ± 0.14 %/d; P < 0.001) when compared with RDA (1.46 ± 0.09 %/d for the whey group; 1.46 ± 0.10 %/d for the pea group); however, it remained unchanged with collagen. Supplemental protein was sufficient to overcome anabolic signaling deficits (mTORC1 and rpS6), corroborating the greater postprandial aminoacidemia. CONCLUSIONS: Our findings demonstrate that supplemental protein provided at breakfast and lunch over the current RDA enhanced anabolic signaling and integrated MPS in older males; however, the source of additional protein may be an important consideration in overcoming age-related anabolic resistance. This trial was registered clinicaltrials.gov as NCT04026607.

Muscle Protein Synthesis in Response to Plant-Based Protein Isolates With and Without Added Leucine Versus Whey Protein in Young Men and Women.

Background: Plant-based protein supplements often contain lower amounts of leucine and other essential amino acids (EAAs), potentially making them less effective in stimulating muscle protein synthesis (MPS) than animal-based proteins. Combining plant proteins could improve the EAA profile and more effectively support MPS. Objectives: The aim of this study was to determine the effect of a novel plant-based blend protein (PBP), PBP with added leucine (PBP + Leu) to levels equivalent to whey protein isolate (WHEY) on aminoacidemia and MPS responses in young men and women. We hypothesized that PBP + Leu would stimulate MPS equivalent to WHEY, and both would be greater than PBP. Methods: We employed a randomized, double-blind, crossover study consisting of 3 separate study visits to compare PBP, PBP + Leu, and WHEY. To measure MPS response to ingestion of the supplements, a primed continuous infusion of L-[ring13C6] phenylalanine was administered for 8 h at each study visit. Skeletal muscle tissue and blood samples were collected to measure aminoacidemia and MPS. Results: All protein supplements increased mixed MPS above postabsorptive levels (P < 0.001). However, MPS increase following ingestion of PBP was less than that following ingestion of PBP + Leu (P = 0.002) and WHEY (P = 0.046). There were no differences in MPS between PBP + Leu and WHEY (P = 0.052). Conclusions: Consumption of PBP isolate with added leucine stimulated MPS to a similar extent as whey protein in young men and women. PBPs containing higher leucine content promote anabolism to a similar extent as animal-based proteins.This study was registered at clinicaltrials.gov as NCT05139160.

Fortetropin supplementation prevents the rise in circulating myostatin but not disuse-induced muscle atrophy in young men with limb immobilization: A randomized controlled trial.

Supplementation with Fortetropin® (FOR), a naturally occurring component from fertilized egg yolks, reduces circulating myostatin concentration. We hypothesized that FOR would mitigate muscle atrophy during immobilization. We examined the effect of FOR supplementation on muscle size and strength during 2-wk of single-leg immobilization and recovery. Twenty-four healthy young men (22 ± 2 yrs; BMI = 24.3 ± 2.9 kg/m2) were randomly allocated to either a Fortetropin® supplement (FOR-SUPP, n = 12) group consuming 19.8 g/d of FOR or placebo (PLA-SUPP, n = 12) group consuming energy- and macronutrient-matched cheese powder for 6-wk. The 6-wk period consisted of 2-wk run-in, 2-wk single-leg immobilization, and 2-wk recovery phase returning to habitual physical activities. Ultrasonography, dual-energy X-ray absorptiometry, muscle biopsies and isometric peak torque assessments were performed prior to and following each phase (days 1, 14, 28, and 42) to measure vastus lateralis and muscle fiber cross-section area (CSA), leg lean mass (LM), and muscular strength. Blood samples were taken on days 1 and 42 for measurement of plasma myostatin concentration, which increased in PLA-SUPP (4221 ± 541 pg/mL to 6721 ± 864 pg/mL, P = 0.013) but not in FOR-SUPP (5487 ± 489 pg/mL to 5383 ± 781 pg/mL, P = 0.900). After the immobilization phase, vastus lateralis CSA, LM, and isometric peak torque were decreased by 7.9 ± 1.7% (P < 0.001), -1.6 ± 0.6% (P = 0.037), and -18.7 ± 2.7% (P < 0.001) respectively, with no difference between groups. The decreased peak torque was recovered after 2-wk of normal activity (vs. day 1, P = 0.129); however, CSA and LM were not recovered (vs. day 1, P < 0.001 and P = 0.003, respectively), with no differences between groups. Supplementation with FOR prevented the rise in circulating myostatin but not disuse-induced muscle atrophy in young men after 2-wk of single-leg immobilization.

An Evidence-Based Narrative Review of Mechanisms of Resistance Exercise-Induced Human Skeletal Muscle Hypertrophy.

Skeletal muscle plays a critical role in physical function and metabolic health. Muscle is a highly adaptable tissue that responds to resistance exercise (RE; loading) by hypertrophying, or during muscle disuse, RE mitigates muscle loss. Resistance exercise training (RET)-induced skeletal muscle hypertrophy is a product of external (e.g., RE programming, diet, some supplements) and internal variables (e.g., mechanotransduction, ribosomes, gene expression, satellite cells activity). RE is undeniably the most potent nonpharmacological external variable to stimulate the activation/suppression of internal variables linked to muscular hypertrophy or countering disuse-induced muscle loss. Here, we posit that despite considerable research on the impact of external variables on RET and hypertrophy, internal variables (i.e., inherent skeletal muscle biology) are dominant in regulating the extent of hypertrophy in response to external stimuli. Thus, identifying the key internal skeletal muscle-derived variables that mediate the translation of external RE variables will be pivotal to determining the most effective strategies for skeletal muscle hypertrophy in healthy persons. Such work will aid in enhancing function in clinical populations, slowing functional decline, and promoting physical mobility. We provide up-to-date, evidence-based perspectives of the mechanisms regulating RET-induced skeletal muscle hypertrophy.

Increased protein intake derived from leucine-enriched protein enhances the integrated myofibrillar protein synthetic response to short-term resistance training in untrained men and women: a 4-day randomized controlled trial.

Leucine is a critical amino acid stimulating myofibrillar protein synthesis (MyoPS). The consumption of higher leucine-containing drinks stimulates MyoPS, but we know less about higher leucine solid foods. Here, we examined the effect of short-term resistance exercise training (STRT) combined with supplementation of a protein and leucine-enriched bar, compared with STRT alone, on integrated (%/day) rates of MyoPS and anabolic protein signaling. In a nonblinded, randomized crossover trial, eight young adults performed four sessions of STRT without or while consuming the study bar (STRT+Leu, 16 g of protein containing ∼3 g of leucine) for two 4-day phases, separated by 2 days nonexercise (Rest) washout. In combination with serial muscle biopsies, deuterated water permitted the measurement of MyoPS and protein signaling phosphorylation. MyoPS during STRT (1.43 ± 0.06%/day) and STRT+Leu (1.53 ± 0.06%/day) were greater than Rest (1.31 ± 0.05%/day), and MyoPS during STRT+Leu (1.53 ± 0.06%/day) was greater than STRT alone (1.43 ± 0.06%/day). STRT+Leu increased the ratio of phosphorylated to total mechanistic target of rapamycin and 4EBP1 compared to Rest. Engaging in STRT increased integrated MyoPS and protein signaling in young adults and was enhanced with increased protein intake derived from a leucine-enriched protein bar. This study was registered at clinicaltrials.gov as NCT03796897.

Both Traditional and Stair Climbing-based HIIT Cardiac Rehabilitation Induce Beneficial Muscle Adaptations.

PURPOSE: There is a lack of knowledge as to how different exercise-based cardiac rehabilitation programming affects skeletal muscle adaptations in coronary artery disease (CAD) patients. We first characterized the skeletal muscle from adults with CAD compared with a group of age- and sex-matched healthy adults. We then determined the effects of a traditional moderate-intensity continuous exercise program (TRAD) or a stair climbing-based high-intensity interval training program (STAIR) on skeletal muscle metabolism in CAD. METHODS: Sixteen adults (n = 16, 61 ± 7 yr), who had undergone recent treatment for CAD, were randomized to perform (3 d·wk-1) either TRAD (n = 7, 30 min at 60%-80% of peak heart rate) or STAIR (n = 9, 3 × 6 flights) for 12 wk. Muscle biopsies were collected at baseline in both CAD and healthy controls (n = 9), and at 4 and 12 wk after exercise training in CAD patients undertaking TRAD or STAIR. RESULTS: We found that CAD had a lower capillary-to-fiber ratio (C/Fi, 35% ± 25%, P = 0.06) and capillary-to-fiber perimeter exchange (CFPE) index (23% ± 29%, P = 0.034) in Type II fibers compared with healthy controls. However, 12 wk of cardiac rehabilitation with either TRAD or STAIR increased C/Fi (Type II, 23% ± 14%, P < 0.001) and CFPE (Type I, 10% ± 23%, P < 0.01; Type II, 18% ± 22%, P = 0.002). CONCLUSION: Cardiac rehabilitation via TRAD or STAIR exercise training improved the compromised skeletal muscle microvascular phenotype observed in CAD patients.

Erratum: McKendry, J., et al. Nutritional Supplements to Support Resistance Exercise in Countering the Sarcopenia of Aging. Nutrients 2020, 12, 2057.

The authors would like to correct an omission in a published paper [...].

Calix[n]triazolium based turn-on fluorescent sensing ensemble for selective adenosine monophosphate (AMP) detection.

A novel calix[n]triazolium was synthesized and exhibited excellent selectivity for AMP. The binding between calix[n]triazolium and chromenolate anions forms a non-fluorescent complex and the resulting supramolecular ensemble selectively detects AMP in water and induces "turn-on" fluorescence. The sensing platform is the first macrocyclic system to discriminate AMP from ADP and ATP through fluorescence changes.

Consumption of High-Leucine-Containing Protein Bar Following Breakfast Impacts Aminoacidemia and Subjective Appetite in Older Persons.

BACKGROUND: Limited data are available examining dietary interventions for optimizing protein and leucine intake to stimulate muscle protein synthesis (MPS) in older humans. OBJECTIVES: We aimed to investigate the aminoacidemia and appetite responses of older adults after consuming breakfast, a meal frequently consumed with high-carbohydrate and below-par amounts of protein and leucine for stimulating MPS. METHODS: Five men and 3 women (means ± SD; age: 74 ± 7 y, BMI: 25.7 ± 4.9 kg/m2, fat- and bone-free mass: 63 ± 7 kg) took part in this experiment in which they consumed breakfasts with low-protein (LP = 13 ± 2 g), high-protein (HP = 32 ± 5 g), and LP followed by a protein- and leucine-enriched bar formulation 2 h later (LP + Bar = 29 ± 2 g). The LP, HP, and LP + Bar breakfast conditions contained 519 ± 86 kcal, 535 ± 83 kcal, and 739 ± 86 kcal, respectively. Blood samples were drawn for 6 h and analyzed for amino acid, insulin, and glucose concentrations. Visual analog scales were assessed for hunger, fullness, and desire to eat. RESULTS: The net AUC for essential amino acid (EAA) exposure was similar between the LP + Bar and HP conditions but greater in the HP condition compared with the LP condition. Peak leucinemia was higher in the LP + Bar condition compared with the HP, and both were greater than the LP condition. Net leucine exposure was similar between HP and LP + Bar, and both were greater than LP. Hunger was similarly reduced in LP + Bar and HP, and LP + Bar resulted in a greater hunger reduction than LP. Both LP + Bar and HP resulted in greater net fullness scores than LP. CONCLUSIONS: Consuming our bar formulation increased blood leucine availability and net exposure to EAAs to a similar degree as consuming a high-protein meal. High-protein at breakfast results in a greater net exposure to EAAs and leucine, which could support MPS in older persons. This study was registered at clinicaltrials.gov as NCT03712761.

Adaptive responses of histone modifications to resistance exercise in human skeletal muscle.

Exercise training causes epigenetic changes in skeletal muscle, although it is unclear how resistance exercise (RE) affects histone modifications. The present study was carried out to investigate the effects of acute RE and RE training on gene expression profiles and histone modifications in human skeletal muscle. Healthy male adults were assigned to acute RE (n = 9, age = 20.5±4.3yr, BMI = 28.0±6.8kg/m2) or RE training (n = 21, age = 23.7±2.5yr, BMI = 24.2±2.7kg/m2) groups. Biopsy samples were obtained from the vastus lateralis muscle before and three hours after a single bout of acute RE, or 3-days after 10 weeks of RE training. RNA sequencing analysis revealed that 153 genes with GO terms including muscle development, stress response, metabolism, cell death, and transcription factor were significantly up-regulated (+291% vs. pre-acute RE) upon acute RE. Expressions of these genes were also greater (+9.6% vs. pre-RE training, p<0.05) in RE trained subjects. Significant up-regulation of acetylated histone 3 (H3) (+235%) and H3 mono-methylated at lysine 4 (+290%) and tri-methylated at lysine 27 (+849%), whereas down-regulation of H3.3 variant (-39%) distributions relative to total H3 were observed at transcriptionally activated loci after acute RE compared to pre-acute RE levels. Interestingly, the distribution of acetylated H3 was found to be up-regulated as compared to the level of total H3 after RE training (+40%, p<0.05). These results indicate that a single bout of RE drastically alters both gene expressions and histone modifications in human skeletal muscle. It is also suggested that enhanced histone acetylation is closely related to up-regulation of gene expressions after RE training.

Recent advances in understanding resistance exercise training-induced skeletal muscle hypertrophy in humans.

Skeletal muscle plays a pivotal role in the maintenance of physical and metabolic health and, critically, mobility. Accordingly, strategies focused on increasing the quality and quantity of skeletal muscle are relevant, and resistance exercise is foundational to the process of functional hypertrophy. Much of our current understanding of skeletal muscle hypertrophy can be attributed to the development and utilization of stable isotopically labeled tracers. We know that resistance exercise and sufficient protein intake act synergistically and provide the most effective stimuli to enhance skeletal muscle mass; however, the molecular intricacies that underpin the tremendous response variability to resistance exercise-induced hypertrophy are complex. The purpose of this review is to discuss recent studies with the aim of shedding light on key regulatory mechanisms that dictate hypertrophic gains in skeletal muscle mass. We also aim to provide a brief up-to-date summary of the recent advances in our understanding of skeletal muscle hypertrophy in response to resistance training in humans.

Nutritional Supplements to Support Resistance Exercise in Countering the Sarcopenia of Aging.

Skeletal muscle plays an indispensable role in metabolic health and physical function. A decrease in muscle mass and function with advancing age exacerbates the likelihood of mobility impairments, disease development, and early mortality. Therefore, the development of non-pharmacological interventions to counteract sarcopenia warrant significant attention. Currently, resistance training provides the most effective, low cost means by which to prevent sarcopenia progression and improve multiple aspects of overall health. Importantly, the impact of resistance training on skeletal muscle mass may be augmented by specific dietary components (i.e., protein), feeding strategies (i.e., timing, per-meal doses of specific macronutrients) and nutritional supplements (e.g., creatine, vitamin-D, omega-3 polyunsaturated fatty acids etc.). The purpose of this review is to provide an up-to-date, evidence-based account of nutritional strategies to enhance resistance training-induced adaptations in an attempt to combat age-related muscle mass loss. In addition, we provide insight on how to incorporate the aforementioned nutritional strategies that may support the growth or maintenance of skeletal muscle and subsequently extend the healthspan of older individuals.

Potato Protein Isolate Stimulates Muscle Protein Synthesis at Rest and with Resistance Exercise in Young Women.

Skeletal muscle myofibrillar protein synthesis (MPS) increases in response to protein feeding and to resistance exercise (RE), where each stimuli acts synergistically when combined. The efficacy of plant proteins such as potato protein (PP) isolate to stimulate MPS is unknown. We aimed to determine the effects of PP ingestion on daily MPS with and without RE in healthy women. In a single blind, parallel-group design, 24 young women (21 ± 3 years, n = 12/group) consumed a weight-maintaining baseline diet containing 0.8 g/kg/d of protein before being randomized to consume either 25 g of PP twice daily (1.6 g/kg/d total protein) or a control diet (CON) (0.8 g/kg/d total protein) for 2 wks. Unilateral RE (~30% of maximal strength to failure) was performed thrice weekly with the opposite limb serving as a non-exercised control (Rest). MPS was measured by deuterated water ingestion at baseline, following supplementation (Rest), and following supplementation + RE (Exercise). Ingestion of PP stimulated MPS by 0.14 ± 0.09 %/d at Rest, and by 0.32 ± 0.14 %/d in the Exercise limb. MPS was significantly elevated by 0.20 ± 0.11 %/d in the Exercise limb in CON (P = 0.008). Consuming PP to increase protein intake to levels twice the recommended dietary allowance for protein augmented rates of MPS. Performance of RE stimulated MPS regardless of protein intake. PP is a high-quality, plant-based protein supplement that augments MPS at rest and following RE in healthy young women.

Resistance Exercise-induced Changes in Muscle Phenotype Are Load Dependent.

INTRODUCTION: Lower-load (LL), higher-repetition resistance exercise training (RET) can increase muscle mass in a similar degree as higher-load (HL), lower-repetition RET. However, little is known about how LL and HL RET modulate other aspects of the RET phenotype such as satellite cells, myonuclei, and mitochondrial proteins. We aimed to investigate changes in muscle mass, muscle strength, satellite cell activity, myonuclear addition, and mitochondrial protein content after prolonged RET with LL and HL RET. METHODS: We recruited 21 young men and randomly assigned them to perform 10 wk RET (leg press, leg extension, and leg curl) three times per week with the following conditions: 80FAIL (80% one-repetition maximum [1RM] performed to volitional fatigue), 30WM (30%1RM with volume matched to 80FAIL), and 30FAIL (30%1RM to volitional fatigue). Skeletal muscle biopsies were taken from the vastus lateralis pre- and post-RET intervention. RESULTS: After 10 wk of RET, only 30FAIL and 80FAIL showed an increase in peak torque and type I fiber cross-sectional area (P < 0.05). Moreover, only 30FAIL resulted in a significant decrease in the myonuclear domain of type II muscle fibers and an increase in mitochondrial proteins related to autophagy, fission, and fusion (all P < 0.05). CONCLUSION: We discovered that LL RET was effective at increasing the content of several mitochondrial proteins. Similar to previous research, we found that changes in muscle mass and strength were independent of load when repetitions were performed to volitional fatigue.

Size prediction of recombinant human growth hormone nanoparticles produced by supercritical fluid precipitation.

Solution-enhanced dispersion by supercritical fluids (SEDS) was applied to produce nano-sized recombinant human growth hormone (hGH) particles. Ethanol was used to help the supercritical carbon dioxide to extract water from the aqueous protein solution. Various sizes of hGH nanoparticles were successfully prepared with a narrow particle size distribution from aqueous ethanol solution without using any additive. The theoretical particle sizes were deduced from the calculated droplet sizes based on a modified Jasuja's equation. The calculated mean particle sizes and the experimentally obtained ones were compared and the results showed an excellent correlation coefficient (R (2)) of 0.995.