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This study had two aims. Aim1 was to determine the agreement between midthigh vastus lateralis (VL) cross-sectional area measured by ultrasound (mCSA US ) versus magnetic resonance imaging (mCSA MRI ) at a single time point, and the ability of each to detect hypertrophic changes. Aim2 was to assess the relationships between pre- and posttraining changes in thigh lean mass determined by dual-energy X-ray absorptiometry (DXA), VL mCSA US , ultrasound-determined VL thickness (VL Thick ), and VL mean myofiber cross-sectional area (fCSA) with changes in VL mCSA MRI . Twelve untrained males (age: 20 ± 1 yr, BMI: 26.9 ± 5.4 kg/m 2 ; n = 12) engaged in a 10-wk resistance training program (2×/week) where right midthigh images and VL biopsies were obtained before and 72 h following the last training bout. Participants' VL mCSA MRI ( P = 0.005), DXA thigh lean mass ( P = 0.015), and VL Thick ( P = 0.001) increased following training, whereas VL mCSA US and fCSA did not. For Aim1 , mCSA US demonstrated excellent concordance [concordance correlation coefficients (CCC) = 0.830] with mCSA MRI , albeit mCSA US values were systematically lower compared with mCSA MRI (mean bias: -2.29 cm 2 ). In addition, PRE-to-POST VL mCSA changes between techniques exhibited good agreement (CCC = 0.700; mean bias: -1.08 cm 2 ). For Aim2 , moderate, positive correlations existed for pre-to-post changes in VL mCSA MRI and DXA thigh lean mass ( r = 0.580, P = 0.048), mCSA US ( r = 0.622, P = 0.031), and VL Thick ( r = 0.520, P = 0.080). A moderate, negative correlation existed between mCSA MRI and fCSA ( r = -0.569, P = 0.054). Our findings have multiple implications: 1 ) resistance training-induced hypertrophy was dependent on the quantification method, 2 ) ultrasound-determined mCSA shows good agreement with MRI, and 3 ) tissue-level changes poorly agreed with mean fCSA changes and this requires further research. NEW & NOTEWORTHY This is the first study to comprehensively examine how different midthigh muscle imaging techniques and histology compare with one another in participants that performed 10 weeks of resistance training. Our study suggests that histology results show poor agreement with results yielded from other common muscle imaging techniques, and researchers should be aware of this limitation.

Background: The Functional Movement Screen (FMS™) is a popular test used by sports medicine professionals to identify dysfunctional movement patterns by analyzing mobility and stability during prescribed movements. Although the FMS™ has been a popular topic of research in recent years, normative data and asymmetries in college-aged students have not been established through research., Purpose: The objective was to determine normative FMS™ scores, report frequency counts for FMS™ asymmetries, and determine if the number of sports seasons and number of different sports an individual participated in during high school varied between university students that showed FMS™ identified asymmetries., Study Design: Cross-sectional Study., Methods: One hundred university students completed the FMS™ and an associated survey to determine which sport(s) and for how many seasons they participated in each sport(s) during high school. Total FMS™ scores were assessed as well as identifying the presence of an asymmetry during a FMS™ screen. An asymmetry within the FMS™ was defined as achieving an unequal score on any of the screens that assessed right versus left movements of the body., Data Analysis: Data analysis included descriptive statistics, Pearson correlation was utilized to investigate the relationship between number of sports played and number of sport seasons. Shapiro Wilk test for normality, and Mann Whitney U test was employed to investigate group differences in number of sports played. All analyses were conducted using SPSS software., Results: Statistically significant correlations (r = .286, r 2 = .08, p < 0.01) were found for both number of sport seasons and number of sports with FMS™ total score. In addition, participants without FMS™-detected asymmetries played significantly more seasons and more sports than their peers that presented asymmetries (U = 946.5, z = -1.98, p = 0.047). Finish with the actual p-value in parenthesis., Conclusion: Participating in multiple sports and multiple sport seasons during high school was associated with higher FMS™ total scores. Results suggest that participating in multiple sports and multiple sport seasons was associated with fewer asymmetries, which may decrease subsequent injury risk., Level of Evidence: 3b., Competing Interests: The authors do not have any conflicts of interest to report.

Purpose: This study aimed to determine the effect of a caffeine-containing supplement on golf-specific performance and fatigue during a 36-hole competitive golf tournament., Methods: Twelve male golfers (34.8 ± 13.9 yr, 175.9 ± 9.3 cm, 81.23 ± 13.14 kg) with a United States Golf Association handicap of 3-10 participated in a double-blind, placebo-controlled, crossover design in which they played an 18-hole round of golf on two consecutive days (36-hole tournament) and were randomly assigned to consume a caffeine-containing supplement (CAF) or placebo (PLA). CAF/PLA was consumed before and after nine holes during each 18-hole round. Total score, drive distance, fairways and greens in regulation, first putt distance, HR, breathing rate, peak trunk acceleration, and trunk posture while putting were recorded. Self-perceived ratings of energy, fatigue, alertness and concentration were also recorded., Results: Total score (76.9 ± 8.1 vs 79.4 ± 9.1, P = 0.039), greens in regulation (8.6 ± 3.3 vs 6.9 ± 4.6, P = 0.035), and drive distance (239.9 ± 33.8 vs 233.2 ± 32.4, P = 0.047) were statistically better during the CAF condition compared with those during PLA. Statistically significant main effects for condition (P < 0.05) and time (P < 0.001) occurred for perceived feelings of energy and fatigue. Compared with PLA, CAF reported more energy (P = 0.025) and less fatigue (P = 0.05) over the competitive round of golf. There were no substantial differences in HR or breathing rates, peak trunk acceleration, or putting posture between conditions or over the round (P > 0.05)., Conclusions: A moderate dose (1.9 ± 0.3 mg · kg(-1)) of caffeine consumed before and during a round of golf improves golf-specific measures of performance and reduces fatigue in skilled golfers.

Background: Naegleria fowleri is a climate-sensitive, thermophilic ameba found in warm, freshwater lakes and rivers. Primary amebic meningoencephalitis (PAM), which is almost universally fatal, occurs when N. fowleri-containing water enters the nose, typically during swimming, and migrates to the brain via the olfactory nerve. In August 2013, a 4-year-old boy died of meningoencephalitis of unknown etiology in a Louisiana hospital., Methods: Clinical and environmental testing and a case investigation were initiated to determine the cause of death and to identify potential exposures., Results: Based on testing of cerebrospinal fluid and brain specimens, the child was diagnosed with PAM. His only reported water exposure was tap water; in particular, tap water that was used to supply water to a lawn water slide on which the child had played extensively prior to becoming ill. Water samples were collected from both the home and the water distribution system that supplied the home and tested; N. fowleri was identified in water samples from both the home and the water distribution system., Conclusions: This case is the first reported PAM death associated with culturable N. fowleri in tap water from a US treated drinking water system. This case occurred in the context of an expanding geographic range for PAM beyond southern states, with recent case reports from Minnesota, Kansas, and Indiana. This case also highlights the role of adequate disinfection throughout drinking water distribution systems and the importance of maintaining vigilance when operating drinking water systems using source waters with elevated temperatures., (Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Transplantation of culture-expanded adult stem/progenitor cells often results in poor cellular engraftment, survival, and migration into sites of tissue injury. Mesenchymal cells including fibroblasts and stromal cells secrete factors that protect injured tissues, promote tissue repair, and support many types of stem/progenitor cells in culture. We hypothesized that secreted factors in conditioned medium (CdM) from adult bone marrow-derived multipotent stromal cells (MSCs) could be used to prime adult cardiac stem/progenitor cells (CSCs/CPCs) and improve graft success after myocardial infarction (MI). Incubation of adult rat CPCs in CdM from human MSCs isolated by plastic adherence or by magnetic sorting against CD271 (a.k.a., p75 low-affinity nerve growth factor receptor; p75MSCs) induced phosphorylation of STAT3 and Akt in CPCs, supporting their proliferation under normoxic conditions and survival under hypoxic conditions (1% oxygen). Priming CSCs with 30× p75MSC CdM for 30 minutes prior to transplantation into subepicardial tissue 1 day after MI markedly increased engraftment compared with vehicle priming. Screening CdM with neutralizing/blocking antibodies identified connective tissue growth factor (CTGF) and Insulin as key factors in p75MSC CdM that protected CPCs. Human CTGF peptide (CTGF-D4) and Insulin synergistically promoted CPC survival during hypoxia in culture. Similar to CdM priming, priming of CSCs with CTGF-D4 and Insulin for 30 minutes prior to transplantation promoted robust engraftment, survival, and migration of CSC derivatives at 1 week and 1 month after MI. Our results indicate that short-term priming of human CSCs with CTGF-D4 and Insulin may improve graft success and cardiac regeneration in patients with MI., (Copyright © 2013 AlphaMed Press.)

The specific cell surface markers on mesenchymal stem/progenitor cells (MSCs) have been poorly defined in vivo, but in one recent study, an MSC subpopulation was directly isolated from a CD271-positive fraction of human bone marrow cells. The aim of this study was to identify circulating CD271(+) MSCs in human peripheral blood and investigate whether the cells are mobilized after acute myocardial infarction (MI). A flow cytometric analysis identified CD45(low/-)CD34(+)CD271(+) cells in adult human peripheral blood. The numbers of circulating CD45(low/-)CD34(+)CD133(+) cells (hematopoietic linage progenitors) were significantly lower in elderly subjects without coronary artery disease than in healthy young subjects, whereas the numbers of CD45(low/-)CD34(+)CD271(+) cells were comparable between elderly subjects and younger subjects. The CD45(low/-)CD34(+)CD271(+) and CD133(+) cell counts were both higher in patients with acute MI than in patients with stable coronary artery disease. In our investigation of the time course changes after acute MI, the CD45(low/-)CD34(+)CD133(+) cell counts gradually increased up to day 7. Over the same period, the CD45(low/-)CD34(+)CD271(+) cell counts peaked at day 3 and then declined up to day 7. Importantly, the CD271(+) cell counts at day 3 were positively correlated with the peak concentrations of creatine kinase after acute MI. Results of the present study suggest that the CD271(+) MSCs are mobilized differently from the CD133(+) hematopoietic progenitors and may play a specific role in the tissue repair process during age-related changes and after acute myocardial infarction.

To determine the influence of age and resistance exercise on myostatin pathway-related genes, younger (n = 10; 28 ± 5 years) and older (n = 10; 68 ± 6 years) men underwent four testing conditions (T1-T4). A baseline (T1) muscle sample was obtained, whereas the second and third biopsies were obtained 48 hours following the first and second training sessions (T2, T3), and a final biopsy was taken 24 hours following T3. The training sessions consisted of 3 sets of 10 repetitions (80% of one repetition maximum) on leg press, hack squat, and leg extension exercises. Follistatin (FST) messenger RNA was greater in older compared with younger men at T1 and T2 (p < .05). Follistatin-like 3 (FSTL3) messenger RNA was greater in older compared with younger men at T1 and T4 (p < .05). In older men, there was a significant decrease in myostatin (MSTN) messenger RNA at T4 (p < .05). Older men contained less active (Ser-425 phosphorylated) SMAD3 (p-SMAD3) protein than younger men at T3 and T4 (p < .05).Although it is well known that younger individuals possess a greater hypertrophic potential to resistance exercise, it appears that older individuals may paradoxically possess a more favorable resistance exercise response regarding myostatin pathway-related genes and a protein marker of pathway activity. Future research is warranted to examine the physiological significance of this age-dependent mechanism.

Androgen signaling occurs primarily via the androgen receptor. Megalin, a low-density lipoprotein endocytic receptor located in various mammalian tissues, has been recently shown to facilitate sex hormone–binding globulin (SHBG) steroid complexes across cell membranes. The purpose of this investigation is to determine if the megalin gene is expressed in human skeletal muscle and if present to determine how megalin and androgen receptor mRNA expression change in response to sequential exercise bouts with respect to aging. Ten younger (age: 18-25 years) and 10 older (age: 60-75 years) men completed 3 workouts (M, W, F) each consisting of 9 sets of lower-body exercises with 10 repetitions per set at 80% 1 repetition maximum. Vastus lateralis muscle biopsies were extracted at baseline (T1), 48 hours after workout 1 (T2) and 2 (T3), and 24 hours after workout 3 (T4), and blood samples were collected before and 5 minutes after each workout. Muscle was analyzed for megalin and androgen receptor expression using gene-specific primers and SYBR green chemistry, and blood was analyzed for serum testosterone, SHBG, and the free androgen index. Megalin was expressed in both young and old subjects across all time points, although no between- or within-group mean differences were detected at any time point. Androgen receptor was expressed higher in young men at all time points compared to in old men (p < 0.05), and a significant correlation (p < 0.05; r = 0.506) was found between serum testosterone and androgen receptor after workout 1. Based on our data, the gene coding for megalin is expressed inside skeletal muscle, but its role, if any, in steroid cellular transport cannot be determined. This finding could lay the groundwork for more mechanistic investigations to better delineate its functional role and its potential as a therapeutic adjunct for androgen-related disorders in healthy and aged populations.

This study was performed to evaluate the combined effect of a meal replacement and an alleged weight loss supplement (WLS) on body composition, fitness parameters, and clinical health in moderately overweight college-aged men and women. Body mass, bench press 1 repetition maximum (1RM), leg press 1RM, body composition, V(O2)max, fasting glucose (GLU), and lipid panels were evaluated before (T1) and after (T2) 8 weeks of combined resistance training (RT) and cardiovascular training (CVT). After T1, subjects were randomly assigned in a double-blind fashion to either the WLS (6 men, 7 women; 21 ± 5 years, 168 ± 8 cm, 75.4 ± 12.7 kg, 31.6 ± 7.7%BFAT) or placebo (PLA: 6 men, 6 women; 22 ± 4 years, 174 ± 9 cm, 84.1 ± 8.8 kg, 30.2 ± 5.6%BFAT) group. Both groups performed 3 d · wk(-1) of combined progressive RT (2 × 12 reps of 8 exercises at 75-80% 1RM) and CVT (30 minutes on a cycle ergometer at 70-85% heart rate reserve). Subjects consumed 4 capsules per day and a once-daily meal replacement throughout the protocol. Percent body fat, bench press 1RM, and leg press 1RM significantly improved (p < 0.05) in both groups. Blood GLU (G × T; p = 0.048) improved in WLS and systolic blood pressure (SBP) approached significance (G × T; p = 0.06) in the WLS group. Follow-up analysis of SBP revealed a significant within-group decrease in the WLS group, whereas no within-group changes were found for either group for GLU. Practically speaking, daily supplementation with a meal replacement and a thrice weekly exercise program can increase fitness levels and improve body composition, whereas adding a thermogenic substance provides no additional benefit over fitness or body composition changes but may favorably alter serum markers of clinical health.

Genes and proteins involved in insulin-like growth factor (IGF)-1 signaling are thought to be differentially expressed in older versus younger mammalian skeletal muscle following acute exercise. The purpose of this study was to examine how multiple bouts of conventional resistance training meant to elicit hypertrophy affect the mRNA expression of IGF-1EA and IGF-1EC (MGF) as well as the expression of total IGF-1 peptides in human skeletal muscle. Ten younger (18-25 years) and 10 older (60-75 years) males completed three sequential workouts (M, W, F) consisting of nine sets of lower body exercises with ten repetitions per set at an intensity of 80% of one repetition maximum. Vastus lateralis muscle biopsies were collected prior to intervention (T1), 48 h following workout 1 (T2), 48 h following workout 2 (T3), and 24 h following workout 3 (T4). RT-PCR was performed to assess baseline and changes in MGF and IGF-IEA mRNA. Samples were also assayed for total muscle IGF-1 peptides using ELISA-based methods. There were no baseline differences in MGF or IGF-1EA mRNA expression and IGF-1 peptides between age groups. Interestingly, MGF expression increased at T2-T4 in the older group relative to baseline values (p < 0.05), albeit muscle IGF-1EA mRNA and IGF-1 peptides remained stably expressed throughout the intervention in both age groups. Repeated conventional exercise bouts resulted in a summative increase in MGF mRNA expression only in older individuals which is contrary to previous research examining this gene at different post-exercise time points, albeit the physiological consequences of these findings remain unknown.