Combined exercise intervention in a mouse model of high-risk neuroblastoma: effects on physical, immune, tumor and clinical outcomes.

Background: Exercise might exert anti-tumoral effects in adult cancers but this question remains open in pediatric tumors, which frequently show a different biology compared to adult malignancies. We studied the effects of an exercise intervention on physical function, immune variables and tumoral response in a preclinical model of a highly aggressive pediatric cancer, high-risk neuroblastoma (HR-NB). Methods: 6-8-week-old male mice with orthotopically-induced HR-NB were assigned to a control (N = 13) or exercise (5-week combined [aerobic+resistance]) group (N = 17). Outcomes included physical function (cardiorespiratory fitness [CRF] and muscle strength), as well as related muscle molecular indicators, blood and tumor immune cell and molecular variables, tumor progression, clinical severity, and survival. Results: Exercise attenuated CRF decline (p=0.029 for the group-by-time interaction effect), which was accompanied by higher muscle levels of oxidative capacity (citrate synthase and respiratory chain complexes III, IV and V) and an indicator of antioxidant defense (glutathione reductase) in the intervention arm (all p≤0.001), as well as by higher levels of apoptosis (caspase-3, p=0.029) and angiogenesis (vascular endothelial growth factor receptor-2, p=0.012). The proportion of 'hot-like' (i.e., with viable immune infiltrates in flow cytometry analyses) tumors tended to be higher (p=0.0789) in the exercise group (76.9%, vs. 33.3% in control mice). Exercise also promoted greater total immune (p=0.045) and myeloid cell (p=0.049) infiltration within the 'hot' tumors, with a higher proportion of two myeloid cell subsets (CD11C+ [dendritic] cells [p=0.049] and M2-like tumor-associated macrophages [p=0.028]), yet with no significant changes in lymphoid infiltrates or in cirulating immune cells or chemokines/cytokines. No training effect was found either for muscle strength or anabolic status, cancer progression (tumor weight and metastasis, tumor microenvironment), clinical severity, or survival. Conclusions: Combined exercise appears as an effective strategy for attenuating physical function decline in a mouse model of HR-NB, also exerting some potential immune benefits within the tumor, which seem overall different from those previously reported in adult cancers.

Tandem gene duplications drive divergent evolution of caffeine and crocin biosynthetic pathways in plants.

BACKGROUND: Plants have evolved a panoply of specialized metabolites that increase their environmental fitness. Two examples are caffeine, a purine psychotropic alkaloid, and crocins, a group of glycosylated apocarotenoid pigments. Both classes of compounds are found in a handful of distantly related plant genera (Coffea, Camellia, Paullinia, and Ilex for caffeine; Crocus, Buddleja, and Gardenia for crocins) wherein they presumably evolved through convergent evolution. The closely related Coffea and Gardenia genera belong to the Rubiaceae family and synthesize, respectively, caffeine and crocins in their fruits. RESULTS: Here, we report a chromosomal-level genome assembly of Gardenia jasminoides, a crocin-producing species, obtained using Oxford Nanopore sequencing and Hi-C technology. Through genomic and functional assays, we completely deciphered for the first time in any plant the dedicated pathway of crocin biosynthesis. Through comparative analyses with Coffea canephora and other eudicot genomes, we show that Coffea caffeine synthases and the first dedicated gene in the Gardenia crocin pathway, GjCCD4a, evolved through recent tandem gene duplications in the two different genera, respectively. In contrast, genes encoding later steps of the Gardenia crocin pathway, ALDH and UGT, evolved through more ancient gene duplications and were presumably recruited into the crocin biosynthetic pathway only after the evolution of the GjCCD4a gene. CONCLUSIONS: This study shows duplication-based divergent evolution within the coffee family (Rubiaceae) of two characteristic secondary metabolic pathways, caffeine and crocin biosynthesis, from a common ancestor that possessed neither complete pathway. These findings provide significant insights on the role of tandem duplications in the evolution of plant specialized metabolism.

Urine Specific Gravity Effect on Total and Segmental Body Composition Validity of Multifrequency Bioelectrical Impedance Analysis Compared With Dual Energy X-Ray Absorptiometry.

ABSTRACT: Fleck, SJ, Hayes, A, Stadler, G, Goesch, T, Goldammer, M, and Braun, S. Urine specific gravity effect on total and segmental body composition validity of multifrequency bioelectrical impedance analysis compared with dual energy x-ray absorptiometry. J Strength Cond Res 35(2): 373-384, 2021-The purposes were to compare body composition measures between a specific multifrequency bioelectrical impedance analyzer (InBody770) and dual-energy x-ray absorptiometry (DXA) and determine if hydration status within a specified range affected these measures. Methods included determining urine specific gravity before testing. Urine specific gravity needed to be within typical well-hydrated (n = 37), euhydrated (n = 45), or slightly dehydrated (n = 20) ranges. Segmental and total body composition measures were determined with the InBody770 and by DXA within the same testing session. Paired sample t-tests revealed significant differences (p < 0.005) between InBody770 and DXA for all body composition variables for all 3 hydration statuses, except for trunk fat-free mass (FFM) and trunk fat mass (FM) of the well-hydrated and euhydrated groups and right leg FM and trunk FFM of the slightly dehydrated group. For the total sample (n = 102), InBody770 significantly underestimated total body FM, right arm FFM, left arm FFM, right leg FFM, and left leg FFM with the range of underestimation being between 0.16 and 2.87 kg. The total body FFM by InBody770 was overestimated by 2.33 ± 2.80 kg or 3.6%. Bland-Altman plots supported these results. The major conclusions are that differences between the InBody770 and DXA segmental and total body FFM and FM are not significantly affected by hydration status in the range investigated, and the FM and FFM determined by the 2 devices are generally significantly different.

Effects of Different Resistance Training Frequencies on Fat in Overweight/Obese Older Women.

AIM: This study compared the effect of different resistance training (RT) frequencies on total, android, gynoid and trunk body fat in overweight/obese older women. METHODS: Fifty-seven overweight/obese older women (66.9±5.3 years and 39.9±4.9% body fat) were randomly assigned to one of three groups: a group performing RT twice a week (G2X), a group performing RT three times a week (G3X), or a non-exercise control group (CG). Both training groups performed the same 12-week RT program consisting of 8 exercises that trained all major muscle groups. Dual-energy X-ray absorptiometry was used to assess body composition. RESULTS: After the intervention period, both G2X and G3X demonstrated significant (P<0.05) reductions in adiposity compared to the CG for total body fat (G2X=-1.7%, G3X=-2.7%, CG=+2.1%), android fat (G2X=-6.2%, G3X=-7.0%, CG=+8.6%), gynoid fat (G2X=-2.5%, G3X=-2.9%, CG=+1.0%), and trunk fat (G2X=-2.5%, G3X=-3.0%, CG=+2.9%), with no significant differences between training groups. CONCLUSION: These results demonstrate that a low-volume 12-week RT program performed two or three times per week causes decreases in total and regional fat deposition with the greatest reductions occurring in the android region.

Effects of Single Set Resistance Training With Different Frequencies on a Cellular Health Indicator in Older Women.

The main purpose of this study was to compare the effects of resistance training (RT) performed two versus three times per week on phase angle (a cellular health indicator) in older women. A total of 39 women (69.1 ± 5.5 years) were randomly assigned to perform a RT program two (G2X) or three (G3X) days per week for 12 weeks. The RT was a whole-body program (eight exercises, one set, 10-15 repetitions). Phase angle, resistance, reactance, and total body water were assessed by bioimpedance spectroscopy. Intracellular water, reactance, and phase angle increased significantly in G2X (2.1%, 3.0%, and 5.6%, respectively) and G3X (5.0%, 6.9%, and 10.3%, respectively) from pretraining to posttraining, with no significant difference between groups. Bioimpedance resistance decreased similarly in both groups (G2X = -1.7% vs. G3X = -3.2%). We conclude that a single set RT program with a frequency of 2 days per week may be sufficient to promote an improvement in cellular health in older women.

Effects of Traditional and Pyramidal Resistance Training Systems on Muscular Strength, Muscle Mass, and Hormonal Responses in Older Women: A Randomized Crossover Trial.

Ribeiro, AS, Schoenfeld, BJ, Fleck, SJ, Pina, FLC, Nascimento, MA, and Cyrino, ES. Effects of traditional and pyramidal resistance training systems on muscular strength, muscle mass, and hormonal responses in older women: a randomized crossover trial. J Strength Cond Res 31(7): 1888-1896, 2017-The purpose of this study was to investigate the effect of resistance training (RT) performed in a pyramid (PR) versus a traditional (TD) system on muscular strength, muscle mass, and hormonal responses in older women. Twenty-five older women (67.6 ± 5.1 years, 65.9 ± 11.1 kg, 154.7 ± 5.8 cm, and 27.5 ± 4.5 kg·m) performed both a TD and PR system RT program in a balanced crossover design. The TD program consisted of 3 sets of 8-12 repetition maximum (RM) with a constant load for the 3 sets, whereas the PR system consisted of 3 sets of 12/10/8-RM with incrementally higher loads for each set. Training was performed in 2 phases of 8 weeks each, with a 12-week washout between the 8-week phases. One repetition maximum (1RM) tests were used as measures of muscular strength. Dual X-ray absorptiometry was used to estimate skeletal muscle mass. Testosterone and IGF-1 concentrations were determined preintervention and postintervention after 12 hours fasting. Significant (p ≤ 0.05) increases were observed in both groups for muscular strength in the 1RM chest press (TD = 12.4% and effect size [ES] = 0.86 vs. PR = 11.5% and ES = 0.74), knee extension (TD = 12.5% and ES = 0.61 vs. PR = 11.8% and ES = 0.62), preacher curl (TD = 10.9% and ES = 0.63 vs. PR = 8.6% and ES = 0.54), and for skeletal muscle mass (TD = 3.6% and ES = 0.32 vs. PR = 2.4% and ES = 0.24) with no differences between groups. There were no significant (p > 0.05) main effects for IGF-1 and testosterone. The results suggest that the PR and TD systems performed are similarly effective for promoting positive adaptations in muscular strength and hypertrophy in older women.

Dose-response of 1, 3, and 5 sets of resistance exercise on strength, local muscular endurance, and hypertrophy.

The study's purpose was to compare the response of performing 1, 3, and 5 sets on measures of performance and muscle hypertrophy. Forty-eight men, with no weight training experience, were randomly assigned to one of the 3 training groups, 1 SET, 3 SETS, 5 SETS, or control group. All training groups performed 3 resistance training sessions per week for 6 months. The 5 repetition maximum (RM) for all training groups increased in the bench press (BP), front lat pull down (LPD), shoulder press (SP), and leg press (LP) (p ≤ 0.05), with the 5 RM increases in the BP and LPD being significantly greater for 5 SETS compared with the other training groups (p ≤ 0.05). Bench press 20 RM in the 3-SET and 5-SET groups significantly increased with the increase being significantly greater than the 1-SET group and the 5-SET group increase being significantly greater than the 3-SET group (p ≤ 0.05). LP 20 RM increased in all training groups (p ≤ 0.05), with the 5-SETS group showing a significantly greater increase than the 1-SET group (p ≤ 0.05). The 3-SET and 5-SET groups significantly increased elbow flexor muscle thickness (MT) with the 5-SET increase being significantly greater than the other 2 training groups (p ≤ 0.05). The 5-SET group significantly increased elbow extensor MT with the increase being significantly greater than the other training groups (p ≤ 0.05). All training groups decreased percent body fat, increased fat-free mass, and vertical jump ability (p ≤ 0.05), with no differences between groups. The results demonstrate a dose-response for the number of sets per exercise and a superiority of multiple sets compared with a single set per exercise for strength gains, muscle endurance, and upper arm muscle hypertrophy.

Benefits of combining inspiratory muscle with 'whole muscle' training in children with cystic fibrosis: a randomised controlled trial.

BACKGROUND: The purpose of this study (randomised controlled trial) was to assess the effects of an 8-week combined 'whole muscle' (resistance+aerobic) and inspiratory muscle training (IMT) on lung volume, inspiratory muscle strength (PImax) and cardiorespiratory fitness (VO2 peak) (primary outcomes), and dynamic muscle strength, body composition and quality of life in paediatric outpatients with CF (cystic fibrosis, secondary outcomes). We also determined the effects of a detraining period. METHODS: Participants were randomly allocated with a block on gender to a control (standard therapy) or intervention group (initial n=10 (6 boys) in each group; age 10±1 and 11±1 years). The latter group performed a combined programme (IMT (2 sessions/day) and aerobic+strength exercises (3 days/week, in-hospital)) that was followed by a 4-week detraining period. All participants were evaluated at baseline, post-training and detraining. RESULTS: Adherence to the training programme averaged 97.5%±1.7%. There was a significant interaction (group×time) effect for PImax, VO2peak and five-repetition maximum strength (leg-press, bench-press, seated-row) (all (p<0.001), and also for %fat (p<0.023) and %fat-free mass (p=0.001), with training exerting a significant beneficial effect only in the intervention group, which was maintained after detraining for PImax and leg-press. CONCLUSION: The relatively short-term (8-week) training programme used here induced significant benefits in important health phenotypes of paediatric patients with CF. IMT is an easily applicable intervention that could be included, together with supervised exercise training in the standard care of these patients.

High quality genomes produced from single MinION flow cells clarify polyploid and demographic histories of critically endangered Fraxinus (ash) species.

With populations of threatened and endangered species declining worldwide, efforts are being made to generate high quality genomic records of these species before they are lost forever. Here, we demonstrate that data from single Oxford Nanopore Technologies (ONT) MinION flow cells can, even in the absence of highly accurate short DNA-read polishing, produce high quality de novo plant genome assemblies adequate for downstream analyses, such as synteny and ploidy evaluations, paleodemographic analyses, and phylogenomics. This study focuses on three North American ash tree species in the genus Fraxinus (Oleaceae) that were recently added to the International Union for Conservation of Nature (IUCN) Red List as critically endangered. Our results support a hexaploidy event at the base of the Oleaceae as well as a subsequent whole genome duplication shared by Syringa, Osmanthus, Olea, and Fraxinus. Finally, we demonstrate the use of ONT long-read sequencing data to reveal patterns in demographic history.

The genome and population genomics of allopolyploid Coffea arabica reveal the diversification history of modern coffee cultivars.

Coffea arabica, an allotetraploid hybrid of Coffea eugenioides and Coffea canephora, is the source of approximately 60% of coffee products worldwide, and its cultivated accessions have undergone several population bottlenecks. We present chromosome-level assemblies of a di-haploid C. arabica accession and modern representatives of its diploid progenitors, C. eugenioides and C. canephora. The three species exhibit largely conserved genome structures between diploid parents and descendant subgenomes, with no obvious global subgenome dominance. We find evidence for a founding polyploidy event 350,000-610,000 years ago, followed by several pre-domestication bottlenecks, resulting in narrow genetic variation. A split between wild accessions and cultivar progenitors occurred ~30.5 thousand years ago, followed by a period of migration between the two populations. Analysis of modern varieties, including lines historically introgressed with C. canephora, highlights their breeding histories and loci that may contribute to pathogen resistance, laying the groundwork for future genomics-based breeding of C. arabica.

Effects on strength, power, and flexibility in adolescents of nonperiodized vs. daily nonlinear periodized weight training.

The aim of this study was to compare 2 models of resistance training (RT) programs, nonperiodized (NP) training and daily nonlinear periodized (DNLP) training, on strength, power, and flexibility in untrained adolescents. Thirty-eight untrained male adolescents were randomly assigned to 1 of 3 groups: a control group, NP RT program, and DNLP program. The subjects were tested pretraining and after 4, 8, and 12 weeks for 1 repetition maximum (1RM) resistances in the bench press and 45° leg press, sit and reach test, countermovement vertical jump (CMVJ), and standing long jump (SLJ). Both training groups performed the same sequence of exercises 3 times a week for a total of 36 sessions. The NP RT consisted of 3 sets of 10-12RM throughout the training period. The DNLP training consisted of 3 sets using different training intensities for each of the 3 training sessions per week. The total volume of the training programs was not significantly different. Both the NP and DNLP groups exhibited a significant increase in the 1RM for the bench press and 45° leg press posttraining compared with that pretraining, but there were no significant differences between groups (p ≤ 0.05). The DNLP group's 1RM changes showed greater percentage improvements and effect sizes. Training intensity for the bench press and 45° leg press did not significantly change during the training. In the CMVJ and SLJ tests, NP and DNLP training showed no significant change. The DNLP group showed a significant increase in the sit and reach test after 8 and 12 weeks of training compared with pretraining; this did not occur with NP training. In summary, in untrained adolescents during a 12-week training period, a DNLP program can be used to elicit similar and possible superior maximal strength and flexibility gains compared with an NP multiset training model.

Physiological profile of elite Chinese female wrestlers.

The purpose of this investigation was to describe the physiological profile of elite, senior Chinese female wrestlers. Twenty-five elite wrestlers, nationally ranked in the top 3 of their weight class, participated in this study. The subjects included Olympic and world champion medalists. The physiological profile included testing of running maximal oxygen consumption (VO2max), 3,200-m run time, 400-m run time, 30-second Wingate anaerobic power and capacity, shoulder, elbow, knee, and trunk isokinetic torque, and 1 repetition maximums (1RMs) in specified exercises. The major results (mean ± SD) were VO2max: 50.58 ± 3.33 ml·kg(-1)·min(-1); 3,200-m run: 14 minutes 1 second ± 49 seconds; 400-m run: 1 minute 11 seconds ± 4 seconds; Wingate maximal anaerobic power: 495.21 ± 79.13 W and mean power: 262.97 ± 52.39 W; 1RM deadlift: 124 ± 19 kg; 1RM deep squat: 98 ± 11 kg; 1RM prone rowing: 72 ± 8 kg; 1RM power clean: 76 ± 12 kg; and 1RM hold and squat: 109 ± 17 kg. In absolute terms in the majority of measures, the heavier weight classes had greater values than the lighter weight classes, but relative to body mass, there were few differences in measures between the weight classes. The Olympic and World Championship medalist had the best value or was at the upper end of a measure's range for the strength and power measures. The results indicate that female wrestling success is not dependent on one physiological characteristic, but that a variety of physiological profiles can result in success. These data on elite female wrestlers can be compared with other wrestlers to help determine individual weaknesses or strengths and to design training programs that result in wrestling success.

Changes in creatine kinase and cortisol in National Collegiate Athletic Association Division I American football players during a season.

The purpose of this study was to track creatine kinase (CK) and serum cortisol over an American college football season starting with the preseason practice. A secondary purpose was to observe changes in basic clinical chemistries. Twenty-two National Collegiate Athletic Association Division I football players (age: 20.4 ± 1.1 years, height: 188.27 ± 8.3 cm, weight: 115.8 ± 29.7 kg) volunteered to participate in this study. Each of the players had participated in the summer strength and conditioning supervised program. Resting blood samples were obtained just before the start of preseason practice (T-1), 2 weeks later (T-2), and the day after game 2 (T-3), game 4 (T-4), game 6 (T-5), and game 9 (T-6) of a 12-game season. Creatine kinase, a panel of clinical chemistries, cortisol, and testosterone were assayed at each time point. No significant changes in CK concentrations were observed over the season with peak values of each range ≤1,070.0 IU·L(-1), but the largest range was observed at T-6 after game 9 (119-2,834 IU·L(-1). The analysis of covariance analysis demonstrated that the number of plays in the ninth game (T-6) explained the magnitude of the changes in CK. No changes in serum cortisol concentrations were observed yet, again large variations existed with peak values of each range ≤465.0 nmol·L(-1). Clinical chemistries showed various significant changes from T-1, but none were considered clinically relevant changes for any player over the time course of the study. In conclusion, the strength and conditioning program before preseason camp or the structure of summer camp practices and the in-season strength and conditioning appeared to mute muscle damage and the stress response of cortisol. Such data demonstrate that changes in muscle damage and adrenal cortical stress over the season are minimal, yet large individual variations can be observed. Management of these variables appears to be related to optimal strength and conditioning and sports medicine programs. Thus, the greater concerns for student-athlete safety in the sport of American football are related to preventing sudden death, traumatic injury, and managing concussion syndromes.

Molecular Phylogenomics Reveals the Deep Evolutionary History of Carnivory across Land Plants.

Plastid molecular phylogenies that broadly sampled angiosperm lineages imply that carnivorous plants evolved at least 11 times independently in 13 families and 6 orders. Within and between these clades, the different prey capture strategies involving flypaper and pitfall structures arose in parallel with the subsequent evolution of snap traps and suction bladders. Attempts to discern the deep ontological history of carnivorous structures using multigene phylogenies have provided a plastid-level picture of sister relationships at the family level. Here, we present a molecular phylogeny of the angiosperms based on nuclear target sequence capture data (Angiosperms-353 probe set), assembled by the Kew Plant Trees of Life initiative, which aims to complete the tree of life for plants. This phylogeny encompasses all carnivorous and protocarnivorous families, although certain genera such as Philcoxia (Plantaginaceae) are excluded. This study offers a novel nuclear gene-based overview of relationships within and between carnivorous families and genera. Consistent with previous broadly sampled studies, we found that most carnivorous families are not affiliated with any single family. Instead, they emerge as sister groups to large clades comprising multiple non-carnivorous families. Additionally, we explore recent genomic studies across various carnivorous clades that examine the evolution of the carnivorous syndrome in relation to whole-genome duplication, subgenome dominance, small-scale gene duplication, and convergent evolution. Furthermore, we discuss insights into genome size evolution through the lens of carnivorous plant genomes.

Activity in GEriatric acute CARe (AGECAR): rationale, design and methods.

BACKGROUND: The Activity in GEriatric acute CARe (AGECAR) is a randomised control trial to assess the effectiveness of an intrahospital strength and walk program during short hospital stays for improving functional capacity of patients aged 75 years or older. METHODS/DESIGN: Patients aged 75 years or older admitted for a short hospital stay (≤ 14 days) will be randomly assigned to either a usual care (control) group or an intervention (training) group. Participants allocated in the usual care group will receive normal hospital care and participants allocated in the intervention group will perform multiple sessions per day of lower limb strength training (standing from a seated position) and walking (10 min bouts) while hospitalized. The primary outcome to be assessed pre and post of the hospital stay will be functional capacity, using the Short Physical Performance Battery (SPPB), and time to walk 10 meters. Besides length of hospitalization, the secondary outcomes that will also be assessed at hospital admission and discharge will be pulmonary ventilation (forced expiratory volume in one second, FEV1) and peripheral oxygen saturation. The secondary outcomes that will be assessed by telephone interview three months after discharge will be mortality, number of falls since discharge, and ability to cope with activities of daily living (ADLs, using the Katz ADL score and Barthel ADL index). DISCUSSION: Results will help to better understand the potential of regular physical activity during a short hospital stay for improving functional capacity in old patients. The increase in life expectancy has resulted in a large segment of the population being over 75 years of age and an increase in hospitalization of this same age group. This calls attention to health care systems and public health policymakers to focus on promoting methods to improve the functional capacity of this population. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT01374893.

Comparison between nonlinear and linear periodized resistance training: hypertrophic and strength effects.

The aim of this study was to investigate the effects of nonlinear periodized (NLP) and linear periodized (LP) resistance training (RT) on muscle thickness (MT) and strength, measured by an ultrasound technique and 1 repetition maximum (1RM), respectively. Thirty untrained men were randomly assigned to 3 groups: NLP (n = 11, age: 30.2 ± 1.1 years, height: 173.6 ± 7.2 cm, weight: 79.5 ± 13.1 kg), LP (n = 10, age: 29.8 ± 1.9 years, height: 172.0 ± 6.8 cm, weight: 79.9 ± 10.6 kg), and control group (CG; n = 9, age: 25.9 ± 3.6 years, height: 171.2 ± 6.3 cm, weight: 73.9 ± 9.9 kg). The right biceps and triceps MT and 1RM strength for the exercises bench press (BP), lat-pull down, triceps extension, and biceps curl (BC) were assessed before and after 12 weeks of training. The NLP program varied training biweekly during weeks 1-6 and on a daily basis during weeks 7-12. The LP program followed a pattern of intensity and volume changes every 4 weeks. The CG did not engage in any RT. Posttraining, both trained groups presented significant 1RM strength gains in all exercises (with the exception of the BP in LP). The 1RM of the NLP group was significantly higher than LP for BP and BC posttraining. There were no significant differences in biceps and triceps MT between baseline and posttraining for any group; however, posttraining, there were significant differences in biceps and triceps MT between NLP and the CG. The effect sizes were higher in NLP for the majority of observed variables. In conclusion, both LP and NLP are effective, but NLP may lead to greater gains in 1RM and MT over a 12-week training period.

Genomic insights into rapid speciation within the world's largest tree genus Syzygium.

Species radiations, despite immense phenotypic variation, can be difficult to resolve phylogenetically when genetic change poorly matches the rapidity of diversification. Genomic potential furnished by palaeopolyploidy, and relative roles for adaptation, random drift and hybridisation in the apportionment of genetic variation, remain poorly understood factors. Here, we study these aspects in a model radiation, Syzygium, the most species-rich tree genus worldwide. Genomes of 182 distinct species and 58 unidentified taxa are compared against a chromosome-level reference genome of the sea apple, Syzygium grande. We show that while Syzygium shares an ancient genome doubling event with other Myrtales, little evidence exists for recent polyploidy events. Phylogenomics confirms that Syzygium originated in Australia-New Guinea and diversified in multiple migrations, eastward to the Pacific and westward to India and Africa, in bursts of speciation visible as poorly resolved branches on phylogenies. Furthermore, some sublineages demonstrate genomic clines that recapitulate cladogenetic events, suggesting that stepwise geographic speciation, a neutral process, has been important in Syzygium diversification.

Relationships between competitive wrestling success and neuroendocrine responses.

Previous research on wrestling suggests winning wrestlers will have a greater increase in testosterone (Tes) than losing wrestlers, although the physiological mechanism is unknown. To determine the role of the sympathetic nervous system in this phenomenon, 12 male wrestlers from an National Collegiate Athletic Association Division I program wrestled 5 matches over a 2-day period. Serum samples were collected pre (Pre) and immediately postmatch (Post) for the determination of Tes, cortisol (Cort), Tes/Cort, and epinephrine (Epi). The subjects had a combined record of 34 wins, 31 losses, and 4 ties. Testosterone increased (p < 0.05) for both winners and losers, but the increase was greater for winners (X ± SE; nmol · L(-1); winners, pre = 16.4 ± 1.2, post = 23.2 ± 1.5; losers, pre = 14.8 ± 1.0, post = 19.4 ± 1.2). Cortisol and Epi increased similarly for both winners and losers, whereas the Tes/Cort ratio was unaltered at any time. Relative changes in the Epi response (%Δ) for losers were correlated to %ΔTes (r = 0.91), whereas winners did not exhibit similar relationships (r = 0.09). These data suggest that winning wrestlers may use a different regulatory mechanism for their acute Tes responses than losers who appear to depend on sympathetic regulation. Additionally, these data from humans support the biosocial theory of status and the challenge hypothesis developed for competing males in other species.

Preliminary findings of a 4-month intrahospital exercise training intervention on IGFs and IGFBPs in children with leukemia.

The aim of this study was to determine the effect of a 16-week intrahospital supervised, conditioning program including both resistance and aerobic type training on insulin-like growth factors 1 and 2 (IGF-1, IGF-2), several IGF-binding proteins (IGFBPs), and growth hormone (GH) in children receiving treatment against acute lymphoblastic leukemia (ALL). We also analyzed the effects of a 20-week detraining period on these hormones. Seven children (3 girls and 4 boys) aged 4-7 years in the maintenance phase of treatment against ALL performed 3 training sessions per week for 16 weeks of resistance (1 set of 8-15 repetitions of 11 exercises) and aerobic training (30 minutes at >or=50% heart rate max) followed by 20 weeks of detraining where no structured exercise program was performed. Levels of IFG-1 and IFG-2 did not significantly change after the intervention period or after the detraining phase. Likewise, levels of GH, IGFBP-2, and IGFBP-3 remained stable pre and posttraining and after the detraining period. IGFBP-1 levels significantly decreased after training (-43.8%, p = 0.014), whereas there were no significant differences between pretraining vs. detraining (-17.8%, p = 0.108) nor between posttraining vs. detraining (17.7%, p = 0.251). Exercise training did not have major effects on the IGFs, IGFBPs, and GH in children with ALL. Although the importance of these findings to long-term cancer prognosis and/or recurrence remains to be determined, the present data (particularly those on IGF-1 and IGFBP-3) support the idea that exercise training can be safely undergone during treatment against ALL with no major adverse effect.

Comparison between constant and decreasing rest intervals: influence on maximal strength and hypertrophy.

Most resistance training programs use constant rest period lengths between sets and exercises, but some programs use decreasing rest period lengths as training progresses. The aim of this study was to compare the effect on strength and hypertrophy of 8 weeks of resistance training using constant rest intervals (CIs) and decreasing rest intervals (DIs) between sets and exercises. Twenty young men recreationally trained in strength training were randomly assigned to either a CI or DI training group. During the first 2 weeks of training, 3 sets of 10-12 repetition maximum (RM) with 2-minute rest intervals between sets and exercises were performed by both groups. During the next 6 weeks of training, the CI group trained using 2 minutes between sets and exercises (4 sets of 8-10RM), and the DI group trained with DIs (2 minutes decreasing to 30 seconds) as the 6 weeks of training progressed (4 sets of 8-10RM). Total training volume of the bench press and squat were significantly lower for the DI compared to the CI group (bench press 9.4%, squat 13.9%) and weekly training volume of these same exercises was lower in the DI group from weeks 6 to 8 of training. Strength (1RM) in the bench press and squat, knee extensor and flexor isokinetic measures of peak torque, and muscle cross-sectional area (CSA) using magnetic resonance imaging were assessed pretraining and posttraining. No significant differences (p < or = 0.05) were shown between the CI and DI training protocols for CSA (arm 13.8 vs. 14.5%, thigh 16.6 vs. 16.3%), 1RM (bench press 28 vs. 37%, squat 34 vs. 34%), and isokinetic peak torque. In conclusion, the results indicate that a training protocol with DI is just as effective as a CI protocol over short training periods (6 weeks) for increasing maximal strength and muscle CSA; thus, either type of program can be used over a short training period to cause strength and hypertrophy.