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1.
Transl Sports Med ; 2024: 3184356, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716482

RESUMEN

Methods: Five electronic databases (PubMed (Medline), Web of Science, Embase, Sport Discus, and Cochrane Library) were searched for controlled trials that assessed the MPS response to RE in healthy, adult humans, postabsorptive state. Individual study and random-effects meta-analysis arewere used to inform the effects of RE and covariates on MPS. Results from 79 controlled trials with 237 participants were analysed. Results: Analysis of the pooled effects revealed robust increases in MPS following RE (weighted mean difference (WMD): 0.032% h-1, 95% CI: [0.024, 0.041] % h-1, I2 = 92%, k = 37, P < 0.001). However, the magnitude of the increase in MPS was lower in older adults (>50 y: WMD: 0.015% h-1, 95% CI: [0.007, 0.022] % h-1, I2 = 76%, k = 12, P = 0.002) compared to younger adults (<35 y: WMD: 0.041% h-1, 95% CI: [0.030, 0.052] % h-1, I2 = 88%, k = 25, P < 0.001). Individual studies have reported that the temporal proximity of the RE, muscle group, muscle protein fraction, RE training experience, and the loading parameters of the RE (i.e., intensity, workload, and effort) appeared to affect the MPS response to RE, whereas sex or type of muscle contraction does not. Conclusion: A single bout of RE can sustain measurable increases in postabsorptive MPS soon after RE cessation and up to 48 h post-RE. However, there is substantial heterogeneity in the magnitude and time course of the MPS response between trials, which appears to be influenced by participants' age and/or the loading parameters of the RE itself.

2.
Genome Biol ; 25(1): 111, 2024 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-38685090

RESUMEN

BACKGROUND: Untranslated regions (UTRs) are important mediators of post-transcriptional regulation. The length of UTRs and the composition of regulatory elements within them are known to vary substantially across genes, but little is known about the reasons for this variation in humans. Here, we set out to determine whether this variation, specifically in 5'UTRs, correlates with gene dosage sensitivity. RESULTS: We investigate 5'UTR length, the number of alternative transcription start sites, the potential for alternative splicing, the number and type of upstream open reading frames (uORFs) and the propensity of 5'UTRs to form secondary structures. We explore how these elements vary by gene tolerance to loss-of-function (LoF; using the LOEUF metric), and in genes where changes in dosage are known to cause disease. We show that LOEUF correlates with 5'UTR length and complexity. Genes that are most intolerant to LoF have longer 5'UTRs, greater TSS diversity, and more upstream regulatory elements than their LoF tolerant counterparts. We show that these differences are evident in disease gene-sets, but not in recessive developmental disorder genes where LoF of a single allele is tolerated. CONCLUSIONS: Our results confirm the importance of post-transcriptional regulation through 5'UTRs in tight regulation of mRNA and protein levels, particularly for genes where changes in dosage are deleterious and lead to disease. Finally, to support gene-based investigation we release a web-based browser tool, VuTR, that supports exploration of the composition of individual 5'UTRs and the impact of genetic variation within them.


Asunto(s)
Regiones no Traducidas 5' , Sistemas de Lectura Abierta , Biosíntesis de Proteínas , Humanos , Dosificación de Gen , Regulación de la Expresión Génica , Sitio de Iniciación de la Transcripción , Empalme Alternativo , Conformación de Ácido Nucleico
3.
Curr Biol ; 34(6): R251-R254, 2024 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-38531320

RESUMEN

An analysis of over 1 million old-growth tropical forest trees reveals that ∼2.2% of species comprise 50% of the individuals in Africa, Amazonia, and Southeast Asia, suggesting that the ecological mechanisms underpinning tree community assembly are ubiquitous across the tropics.


Asunto(s)
Árboles , Clima Tropical , África , Brasil , Ecosistema , Bosques
4.
Nutrients ; 15(19)2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37836496

RESUMEN

An increase in the intake of legumes is recommended in the promotion of plant-sourced (PSP) rather than animal-sourced (ASP) protein intake to produce a more sustainable diet. This study evaluated the quality of novel PSP isolates from pea (PEA) and fava bean (FAVA) and an ASP isolate of whey (WHEY) and compared the magnitude and temporal pattern of peripheral arterial aminoacidemia following ingestion of 0.33 g·kg-1 body mass of protein isolate in healthy young adult men (n = 9). Total indispensable amino acids (IAA) comprised 58% (WHEY), 46% (PEA), and 42% (FAVA) of the total amino acid (AA) composition, with the ingested protein providing 108% (WHEY), 77% (PEA), and 67% (FAVA) of the recommended per diem requirement of IAA. Reflecting the AA composition, the area under the curve (∆AUC0-180), post-ingestion increase in total IAA for WHEY was 41% (p < 0.001) and 57% (p < 0.001) greater than PEA and FAVA, respectively, with PEA exceeding FAVA by 28% (p = 0.003). As a sole-source, single-dose meal-size serving, the lower total IAA for PEA and FAVA would likely evoke a reduced post-prandial anabolic capacity compared to WHEY. Incorporated into a food matrix, the promotion of PSP isolates contributes to a more sustainable diet.


Asunto(s)
Vicia faba , Suero Lácteo , Humanos , Adulto Joven , Masculino , Animales , Suero Lácteo/metabolismo , Vicia faba/metabolismo , Pisum sativum/metabolismo , Proteína de Suero de Leche/metabolismo , Aminoácidos , Ingestión de Alimentos
5.
Nat Commun ; 14(1): 853, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36792598

RESUMEN

Following the diagnosis of a paediatric disorder caused by an apparently de novo mutation, a recurrence risk of 1-2% is frequently quoted due to the possibility of parental germline mosaicism; but for any specific couple, this figure is usually incorrect. We present a systematic approach to providing individualized recurrence risk. By combining locus-specific sequencing of multiple tissues to detect occult mosaicism with long-read sequencing to determine the parent-of-origin of the mutation, we show that we can stratify the majority of couples into one of seven discrete categories associated with substantially different risks to future offspring. Among 58 families with a single affected offspring (representing 59 de novo mutations in 49 genes), the recurrence risk for 35 (59%) was decreased below 0.1%, but increased owing to parental mixed mosaicism for 5 (9%)-that could be quantified in semen for paternal cases (recurrence risks of 5.6-12.1%). Implementation of this strategy offers the prospect of driving a major transformation in the practice of genetic counselling.


Asunto(s)
Padre , Parto , Masculino , Embarazo , Femenino , Humanos , Niño , Mutación , Medición de Riesgo , Células Germinativas , Mosaicismo , Linaje , Mutación de Línea Germinal
6.
Int J Sports Physiol Perform ; 18(2): 195-203, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36634311

RESUMEN

PURPOSE: To compare the effects of bilateral strength training (BLST) versus unilateral strength training (ULST) on changes in peak force (PF) and interlimb asymmetry (ILA) in the isometric squat at a 120° knee angle (ISq120). METHOD: A total of 31 young, recreationally strength-trained men performed either BLST (n = 18) or ULST (n = 13), twice per week for 6 weeks. The total number of repetitions, duty cycle, and effort were standardized between training groups (ie, differing only in the exercises performed). Changes in PF and ILA were assessed pretraining and posttraining. RESULTS: Comparable increases in PF were observed in the BLST group (mean [SD] change; 17.4% [20.5%], P = .001, standardized mean difference [SMD] = 0.45) and the ULST group (11.4% [19.1%], P = .042, SMD = 0.25). No significant changes in symmetry index (SI) scores were observed following BLST (mean [SD] change; 0 [5.7], P = .526, SMD = -0.12) or ULST (+3 [6.0], P = .702, SMD = 0.4). Individual analyses of subjects with marked ILA (ie, baseline SI score > baseline coefficient of variation) revealed a trend toward BLST being more effective at attenuating SI scores in the ISq120. CONCLUSIONS: Overall, both BLST and ULST are effective for increasing ISq120 PF. However, it appears that BLST may be more effective at reducing SI scores in those with marked ILA.


Asunto(s)
Entrenamiento de Fuerza , Masculino , Humanos , Músculo Esquelético , Fuerza Muscular , Contracción Isométrica , Postura
7.
Med Sci (Basel) ; 10(4)2022 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-36278523

RESUMEN

BACKGROUND: Guidelines for the management of polycystic ovary syndrome (PCOS) focus on lifestyle changes, incorporating exercise. Whilst evidence suggests that aerobic exercise may be beneficial, less is known about the effectiveness of resistance training (RT), which may be more feasible for those that have low fitness levels and/or are unable to tolerate/participate in aerobic exercise. OBJECTIVES: To identify the available evidence on RT in women with PCOS and to summarise findings in the context of a scoping review. ELIGIBILITY CRITERIA: Studies utilising pre-post designs to assess the effectiveness of RT in PCOS; all outcomes were included. SOURCES OF EVIDENCE: Four databases (PubMed, CENTRAL, CINAHL and SportDiscus) were searched and supplemented by hand searching of relevant papers/reference lists. CHARTING METHODS: Extracted data were presented in tables and qualitatively synthesised. RESULTS: Searches returned 42 papers; of those, 12 papers were included, relating to six studies/trials. Statistical changes were reported for multiple pertinent outcomes relating to metabolic (i.e., glycaemia and fat-free mass) and hormonal (i.e., testosterone and sex hormone-binding globulin) profiles. CONCLUSIONS: There is a striking lack of studies in this field and, despite the reported statistical significance for many outcomes, the documented magnitude of changes are small and the quality of the evidence questionable. This highlights an unmet need for rigorously designed/reported and sufficiently powered trials.


Asunto(s)
Síndrome del Ovario Poliquístico , Entrenamiento de Fuerza , Humanos , Femenino , Síndrome del Ovario Poliquístico/terapia , Globulina de Unión a Hormona Sexual , Estilo de Vida , Testosterona
8.
Nutrients ; 14(18)2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36145064

RESUMEN

The aim of the present study was to evaluate the effect of feeding fava bean (Vicia faba L.) protein (FBP) on resting and post-exercise myofibrillar fractional synthetic rate (myoFSR). In a parallel, double-blind, randomised control trial, sixteen young, healthy recreationally active adults (age = 25 (5) years, body mass = 70 (15) kg, stature = 1.72 (0.11) m, mean (SD)) ingested 0.33 g·kg-1 FBP (n = 8) or a negative control (CON, i.e., EAA-free mixture) (n = 8), immediately after a bout of unilateral knee-extensor resistance exercise. Plasma, saliva, and m. vastus lateralis muscle samples were obtained pre-ingestion and 3 h post-ingestion. MyoFSR was calculated via deuterium labelling of myofibrillar-bound alanine, measured by gas chromatography-pyrolysis-isotope ratio mass spectrometry (GC-Pyr-IRMS). Resistance exercise increased myoFSR (p = 0.012). However, ingestion of FBP did not evoke an increase in resting (FBP 29 [-5, 63] vs. CON 12 [-25, 49]%, p = 0.409, mean % change [95% CI]) or post-exercise (FBP 78 [33, 123]% vs. CON 58 [9, 107]%, p = 0.732) myoFSR. Ingestion of 0.33 g·kg-1 of FBP does not appear to enhance resting or post-exercise myoFSR in young, healthy, recreationally active adults.


Asunto(s)
Entrenamiento de Fuerza , Vicia faba , Adulto , Alanina/metabolismo , Deuterio/metabolismo , Ingestión de Alimentos , Femenino , Humanos , Masculino , Músculo Esquelético/metabolismo
9.
G3 (Bethesda) ; 12(1)2022 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-34791208

RESUMEN

Combining samples for genetic association is standard practice in human genetic analysis of complex traits, but is rarely undertaken in rodent genetics. Here, using 23 phenotypes and genotypes from two independent laboratories, we obtained a sample size of 3076 commercially available outbred mice and identified 70 loci, more than double the number of loci identified in the component studies. Fine-mapping in the combined sample reduced the number of likely causal variants, with a median reduction in set size of 51%, and indicated novel gene associations, including Pnpo, Ttll6, and GM11545 with bone mineral density, and Psmb9 with weight. However, replication at a nominal threshold of 0.05 between the two component studies was low, with less than one-third of loci identified in one study replicated in the second. In addition to overestimates in the effect size in the discovery sample (Winner's Curse), we also found that heterogeneity between studies explained the poor replication, but the contribution of these two factors varied among traits. Leveraging these observations, we integrated information about replication rates, study-specific heterogeneity, and Winner's Curse corrected estimates of power to assign variants to one of four confidence levels. Our approach addresses concerns about reproducibility and demonstrates how to obtain robust results from mapping complex traits in any genome-wide association study.


Asunto(s)
Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Animales , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo/métodos , Ratones , Herencia Multifactorial , Péptido Sintasas , Fenotipo , Reproducibilidad de los Resultados
10.
Sports (Basel) ; 9(10)2021 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-34678921

RESUMEN

This study aimed to investigate the test-retest reliability of peak force in the isometric squat across the strength spectrum using coefficient of variation (CV) and intra-class correlation coefficient (ICC). On two separate days, 59 healthy men (mean (SD) age 23.0 (4.1) years; height 1.79 (0.7) m; body mass 84.0 (15.2) kg) performed three maximal effort isometric squats in two positions (at a 120° and a 90° knee angle). Acceptable reliability was observed at both the 120° (CV = 7.5 (6.7), ICC = 0.960 [0.933, 0.977]) and 90° positions (CV = 9.2 (8.8), ICC = 0.920 [0.865, 0.953]). There was no relationship between peak force in the isometric squat and the test-retest reliability at either the 120° (r = 0.052, p = 0.327) or 90° (r = 0.014, p = 0.613) positions. A subgroup of subjects (n = 17) also completed the isometric squat test at a 65° knee angle. Acceptable reliability was observed in this position (CV = 9.6 (9.3), ICC = 0.916 [0.766, 0.970]) and reliability was comparable to the 120° and 90° positions. Therefore, we deem isometric squat peak force output to be a valid and reliable measure across the strength spectrum and in different isometric squat positions.

11.
Mol Biol Evol ; 38(9): 3497-3511, 2021 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-34129037

RESUMEN

Ancient genomes anchor genealogies in directly observed historical genetic variation and contextualize ancestral lineages with archaeological insights into their geography and cultural associations. However, the majority of ancient genomes are of lower coverage and cannot be directly built into genealogies. Here, we present a fast and scalable method, Colate, the first approach for inferring ancestral relationships through time between low-coverage genomes without requiring phasing or imputation. Our approach leverages sharing patterns of mutations dated using a genealogy to infer coalescence rates. For deeply sequenced ancient genomes, we additionally introduce an extension of the Relate algorithm for joint inference of genealogies incorporating such genomes. Application to 278 present-day and 430 ancient DNA samples of >0.5x mean coverage allows us to identify dynamic population structure and directional gene flow between early farmer and European hunter-gatherer groups. We further show that the previously reported, but still unexplained, increase in the TCC/TTC mutation rate, which is strongest in West Eurasia today, was already present at similar strength and widespread in the Late Glacial Period ~10k-15k years ago, but is not observed in samples >30k years old. It is strongest in Neolithic farmers, and highly correlated with recent coalescence rates between other genomes and a 10,000-year-old Anatolian hunter-gatherer. This suggests gene-flow among ancient peoples postdating the last glacial maximum as widespread and localizes the driver of this mutational signal in both time and geography in that region. Our approach should be widely applicable in future for addressing other evolutionary questions, and in other species.


Asunto(s)
ADN Antiguo , Genoma , Flujo Génico , Genética de Población , Geografía , Historia Antigua , Dinámica Poblacional
12.
Nat Genet ; 53(7): 1104-1111, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34083788

RESUMEN

Inexpensive genotyping methods are essential to modern genomics. Here we present QUILT, which performs diploid genotype imputation using low-coverage whole-genome sequence data. QUILT employs Gibbs sampling to partition reads into maternal and paternal sets, facilitating rapid haploid imputation using large reference panels. We show this partitioning to be accurate over many megabases, enabling highly accurate imputation close to theoretical limits and outperforming existing methods. Moreover, QUILT can impute accurately using diverse technologies, including long reads from Oxford Nanopore Technologies, and a new form of low-cost barcoded Illumina sequencing called haplotagging, with the latter showing improved accuracy at low coverages. Relative to DNA genotyping microarrays, QUILT offers improved accuracy at reduced cost, particularly for diverse populations that are traditionally underserved in modern genomic analyses, with accuracy nearly doubling at rare SNPs. Finally, QUILT can accurately impute (four-digit) human leukocyte antigen types, the first such method from low-coverage sequence data.


Asunto(s)
Biología Computacional/métodos , Genotipo , Técnicas de Genotipaje , Secuenciación Completa del Genoma , Biología Computacional/economía , Diploidia , Humanos , Polimorfismo de Nucleótido Simple , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN
13.
J Environ Manage ; 283: 112009, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33508552

RESUMEN

Meeting rising demand for oil palm whilst minimizing the loss of tropical biodiversity and associated ecosystem functions is a core conservation challenge. One potential solution is focusing the expansion of high-yielding crops on presently low-yielding farmlands alongside protecting nearby tropical forests that can enhance provision of ecosystem functions. A key question is how this solution would impact invertebrate functional diversity. We focus on oil palm in the Colombian Llanos, where plantations are replacing improved cattle pastures and forest fragments, and on dung beetles, which play key functional roles in nutrient cycling and secondary seed dispersal. We show that functional richness and functional diversity of dung beetles is greater in oil palm than in cattle pasture, and that functional metrics did not differ between oil palm and remnant forest. The abundance-size class profile of dung beetles in oil palm was more similar to forest than to pasture, which had lower abundances of the smallest and largest dung beetles. The abundance of tunneling and rolling dung beetles did not differ between oil palm and forest, while higher forest cover increased the abundance of diurnal and generalist-feeding beetles in oil palm landscapes. This suggests that prioritizing agricultural development on low-yielding cattle pasture will have positive effects on functional diversity and highlights the need for forest protection to maintain ecosystem functioning within agricultural landscapes.


Asunto(s)
Escarabajos , Agricultura , Animales , Biodiversidad , Bovinos , Ecosistema , Bosques
14.
Genome Res ; 31(1): 110-120, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33208456

RESUMEN

Quantifying and comparing the amount of adaptive evolution among different species is key to understanding how evolution works. Previous studies have shown differences in adaptive evolution across species; however, their specific causes remain elusive. Here, we use improved modeling of weakly deleterious mutations and the demographic history of the outgroup species and ancestral population and estimate that at least 20% of nonsynonymous substitutions between humans and an outgroup species were fixed by positive selection. This estimate is much higher than previous estimates, which did not correct for the sizes of the outgroup species and ancestral population. Next, we jointly estimate the proportion and selection coefficient (p + and s +, respectively) of newly arising beneficial nonsynonymous mutations in humans, mice, and Drosophila melanogaster by examining patterns of polymorphism and divergence. We develop a novel composite likelihood framework to test whether these parameters differ across species. Overall, we reject a model with the same p + and s + of beneficial mutations across species and estimate that humans have a higher p+s + compared with that of D. melanogaster and mice. We show that this result cannot be caused by biased gene conversion or hypermutable CpG sites. We discuss possible biological explanations that could generate the observed differences in the amount of adaptive evolution across species.


Asunto(s)
Drosophila melanogaster , Mutación , Aminoácidos , Animales , Drosophila melanogaster/genética , Evolución Molecular , Humanos , Ratones , Polimorfismo Genético
15.
Nat Med ; 26(12): 1912-1918, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33169016

RESUMEN

The 22q11.2 deletion syndrome (22q11DS) is associated with a 20-25% risk of schizophrenia. In a cohort of 962 individuals with 22q11DS, we examined the shared genetic basis between schizophrenia and schizophrenia-related early trajectory phenotypes: sub-threshold symptoms of psychosis, low baseline intellectual functioning and cognitive decline. We studied the association of these phenotypes with two polygenic scores, derived for schizophrenia and intelligence, and evaluated their use for individual risk prediction in 22q11DS. Polygenic scores were not only associated with schizophrenia and baseline intelligence quotient (IQ), respectively, but schizophrenia polygenic score was also significantly associated with cognitive (verbal IQ) decline and nominally associated with sub-threshold psychosis. Furthermore, in comparing the tail-end deciles of the schizophrenia and IQ polygenic score distributions, 33% versus 9% of individuals with 22q11DS had schizophrenia, and 63% versus 24% of individuals had intellectual disability. Collectively, these data show a shared genetic basis for schizophrenia and schizophrenia-related phenotypes and also highlight the future potential of polygenic scores for risk stratification among individuals with highly, but incompletely, penetrant genetic variants.


Asunto(s)
Síndrome de DiGeorge/genética , Variación Genética/genética , Discapacidad Intelectual/genética , Esquizofrenia/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/genética , Disfunción Cognitiva/fisiopatología , Estudios de Cohortes , Síndrome de DiGeorge/epidemiología , Síndrome de DiGeorge/fisiopatología , Femenino , Humanos , Discapacidad Intelectual/epidemiología , Discapacidad Intelectual/fisiopatología , Masculino , Persona de Mediana Edad , Herencia Multifactorial/genética , Fenotipo , Factores de Riesgo , Esquizofrenia/epidemiología , Esquizofrenia/fisiopatología , Adulto Joven
16.
Nutrients ; 12(8)2020 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-32806532

RESUMEN

The quality and nutritional value of dietary proteins are determined by the quantity, digestibility and bioavailability of essential amino acids (EAA), which play a critical role in human growth, longevity and metabolic health. Plant-source protein is often deficient in one or more EAAs (e.g., branched-chain amino acids, lysine, methionine and/or tryptophan) and, in its natural form, is less digestible than animal-source protein. Nevertheless, dietary intake of plant-source protein has been promoted because of its potential health benefits, lower cost of production and lower environmental impact compared to animal-source protein. Implementation of dietary strategies that improve both human and planetary health are of critical importance and subject to growing interest from researchers and consumers. Therefore, in this review we analyse current plant protein intake patterns and discuss possible countermeasures that can enhance plant protein nutrition, examples include: (1) combining different plant proteins with complementary EAA profiles; (2) identification and commercial cultivation of new and novel high-quality plant proteins; (3) industrial and domestic processing methods; and (4) genome-editing techniques.


Asunto(s)
Aminoácidos Esenciales/análisis , Dieta Saludable , Proteínas en la Dieta/análisis , Valor Nutritivo , Proteínas de Plantas/análisis , Agricultura/métodos , Manipulación de Alimentos/métodos , Humanos
17.
Nutrients ; 12(3)2020 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-32245197

RESUMEN

BACKGROUND: The aim of this study was to investigate the effect of whey protein supplementation on myofibrillar protein synthesis (myoPS) and muscle recovery over a 7-d period of intensified resistance training (RT). METHODS: In a double-blind randomised parallel group design, 16 resistance-trained men aged 18 to 35 years completed a 7-d RT protocol, consisting of three lower-body RT sessions on non-consecutive days. Participants consumed a controlled diet (146 kJ·kg-1·d-1, 1.7 g·kg-1·d-1 protein) with either a whey protein supplement or an isonitrogenous control (0.33 g·kg-1·d-1 protein). To measure myoPS, 400 ml of deuterium oxide (D2O) (70 atom %) was ingested the day prior to starting the study and m. vastus lateralis biopsies were taken before and after RT-intervention. Myofibrillar fractional synthetic rate (myoFSR) was calculated via deuterium labelling of myofibrillar-bound alanine, measured by gas chromatography-pyrolysis-isotope ratio mass spectrometry (GC-Pyr-IRMS). Muscle recovery parameters (i.e., countermovement jump height, isometric-squat force, muscle soreness and serum creatine kinase) were assessed daily. RESULTS: MyoFSR PRE was 1.6 (0.2) %∙d-1 (mean (SD)). Whey protein supplementation had no effect on myoFSR (p = 0.771) or any recovery parameter (p = 0.390-0.989). CONCLUSIONS: Over an intense 7-d RT protocol, 0.33 g·kg-1·d-1 of supplemental whey protein does not enhance day-to-day measures of myoPS or postexercise recovery in resistance-trained men.


Asunto(s)
Suplementos Dietéticos , Músculo Esquelético/metabolismo , Miofibrillas/metabolismo , Biosíntesis de Proteínas , Entrenamiento de Fuerza , Proteína de Suero de Leche/administración & dosificación , Adolescente , Adulto , Biomarcadores , Expresión Génica , Humanos , Masculino , Fuerza Muscular , Adulto Joven
18.
Nat Commun ; 10(1): 3900, 2019 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-31467277

RESUMEN

During meiotic recombination, homologue-templated repair of programmed DNA double-strand breaks (DSBs) produces relatively few crossovers and many difficult-to-detect non-crossovers. By intercrossing two diverged mouse subspecies over five generations and deep-sequencing 119 offspring, we detect thousands of crossover and non-crossover events genome-wide with unprecedented power and spatial resolution. We find that both crossovers and non-crossovers are strongly depleted at DSB hotspots where the DSB-positioning protein PRDM9 fails to bind to the unbroken homologous chromosome, revealing that PRDM9 also functions to promote homologue-templated repair. Our results show that complex non-crossovers are much rarer in mice than humans, consistent with complex events arising from accumulated non-programmed DNA damage. Unexpectedly, we also find that GC-biased gene conversion is restricted to non-crossover tracts containing only one mismatch. These results demonstrate that local genetic diversity profoundly alters meiotic repair pathway decisions via at least two distinct mechanisms, impacting genome evolution and Prdm9-related hybrid infertility.


Asunto(s)
Roturas del ADN de Doble Cadena , Variación Genética , Recombinación Homóloga , Alelos , Animales , Proteínas de Ciclo Celular/genética , Cromosomas , Intercambio Genético , Daño del ADN , Reparación de la Incompatibilidad de ADN , Femenino , Conversión Génica , N-Metiltransferasa de Histona-Lisina/genética , Histonas/genética , Humanos , Hibridación Genética , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Genéticos , Proteínas de Unión a Fosfato/genética , Polimorfismo de Nucleótido Simple , Reparación del ADN por Recombinación
19.
Nutrients ; 11(7)2019 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-31331099

RESUMEN

The aim of this study was to test the effects of two disparate isonitrogenous, isocaloric pre-exercise feeds on deuterium-oxide (D2O) derived measures of myofibrillar protein synthesis (myoPS) in humans. Methods: In a double-blind parallel group design, 22 resistance-trained men aged 18 to 35 years ingested a meal (6 kcal·kg-1, 0.8 g·kg-1 carbohydrate, 0.2 g·kg-1 fat) with 0.33 g·kg-1 nonessential amino acids blend (NEAA) or whey protein (WHEY), prior to resistance exercise (70% 1RM back-squats, 10 reps per set to failure, 25% duty cycle). Biopsies of M. vastus lateralis were obtained pre-ingestion (PRE) and +3 h post-exercise (POST). The myofibrillar fractional synthetic rate (myoFSR) was calculated via deuterium labelling of myofibrillar-bound alanine, measured by gas chromatography-pyrolysis-isotope ratio mass spectrometry (GC-Pyr-IRMS). Data are a mean percentage change (95% CI). Results: There was no discernable change in myoFSR following NEAA (10(-5, 25) %, p = 0.235), whereas an increase in myoFSR was observed after WHEY (28 (13, 43) %, p = 0.003). Conclusions: Measured by a D2O tracer technique, a disparate myoPS response was observed between NEAA and WHEY. Pre-exercise ingestion of whey protein increased post-exercise myoPS, whereas a NEAA blend did not, supporting the use of NEAA as a viable isonitrogenous negative control.


Asunto(s)
Aminoácidos/administración & dosificación , Ejercicio Físico/fisiología , Proteínas Musculares/biosíntesis , Miofibrillas/metabolismo , Proteína de Suero de Leche/administración & dosificación , Adolescente , Adulto , Aminoácidos/sangre , Aminoácidos Esenciales/administración & dosificación , Aminoácidos Esenciales/sangre , Método Doble Ciego , Humanos , Masculino , Biosíntesis de Proteínas/efectos de los fármacos , Entrenamiento de Fuerza , Adulto Joven
20.
J Clin Invest ; 129(8): 3171-3184, 2019 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-31264976

RESUMEN

Arrhythmogenic cardiomyopathy (ACM) is an inherited arrhythmia syndrome characterized by severe structural and electrical cardiac phenotypes, including myocardial fibrofatty replacement and sudden cardiac death. Clinical management of ACM is largely palliative, owing to an absence of therapies that target its underlying pathophysiology, which stems partially from our limited insight into the condition. Following identification of deceased ACM probands possessing ANK2 rare variants and evidence of ankyrin-B loss of function on cardiac tissue analysis, an ANK2 mouse model was found to develop dramatic structural abnormalities reflective of human ACM, including biventricular dilation, reduced ejection fraction, cardiac fibrosis, and premature death. Desmosomal structure and function appeared preserved in diseased human and murine specimens in the presence of markedly abnormal ß-catenin expression and patterning, leading to identification of a previously unknown interaction between ankyrin-B and ß-catenin. A pharmacological activator of the WNT/ß-catenin pathway, SB-216763, successfully prevented and partially reversed the murine ACM phenotypes. Our findings introduce what we believe to be a new pathway for ACM, a role of ankyrin-B in cardiac structure and signaling, a molecular link between ankyrin-B and ß-catenin, and evidence for targeted activation of the WNT/ß-catenin pathway as a potential treatment for this disease.


Asunto(s)
Ancirinas , Displasia Ventricular Derecha Arritmogénica , Miocardio , Vía de Señalización Wnt , Animales , Ancirinas/genética , Ancirinas/metabolismo , Displasia Ventricular Derecha Arritmogénica/genética , Displasia Ventricular Derecha Arritmogénica/metabolismo , Displasia Ventricular Derecha Arritmogénica/patología , Modelos Animales de Enfermedad , Femenino , Humanos , Indoles/farmacología , Masculino , Maleimidas/farmacología , Ratones , Ratones Noqueados , Miocardio/metabolismo , Miocardio/patología , beta Catenina/genética , beta Catenina/metabolismo
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