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1.
Int J Sports Med ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38684188

RESUMO

We analyzed the effects of load magnitude and bar velocity variables on sensitivity to fatigue. Seventeen resistance-trained men (age=25.7±4.9 years; height=177.0±7.2 cm; body mass=77.7±12.3 kg; back-squat 1RM=145.0±33.9 kg; 1RM/body mass=1.86) participated in the study. Pre- and post-exercise changes in the mean propulsive velocity (MPV) and peak velocity (PV) in the back-squat at different intensities were compared with variations in the countermovement jump (CMJ). CMJ height decreased significantly from pre- to post-exercise (∆%=-7.5 to -10.4; p<0.01; ES=0.37 to 0.60). Bar velocity (MPV and PV) decreased across all loads (∆%=-4.0 to -12.5; p<0.01; ES=0.32 to 0.66). The decrease in performance was similar between the CMJ, MPV (40% and 80% 1RM; p=1.00), and PV (80% 1RM; p=1.00). The magnitude of reduction in CMJ performance was greater than MPV (60% 1RM; p=0.05) and PV (40% and 60% 1RM; p<0.01) at the post-exercise moment. Low systematic bias and acceptable levels of agreement were only found between CMJ and MPV at 40% and 80% 1RM (bias=0.35 to 1.59; ICC=0.51 to 0.71; CV=5.1% to 8.5%). These findings suggest that the back-squat at 40% or 80% 1RM using MPV provides optimal sensitivity to monitor fatigue through changes in bar velocity.

2.
Int J Sport Nutr Exerc Metab ; 34(3): 137-144, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38458183

RESUMO

There is a lack of evidence on the additional benefits of combining caffeine (CAF) and creatine (CRE) supplementation on anaerobic power and capacity. Thus, the aim of the present study was to test the effects of combined and isolated supplementation of CAF and CRE on anaerobic power and capacity. Twenty-four healthy men performed a baseline Wingate anaerobic test and were then allocated into a CRE (n = 12) or placebo (PLA; n = 12) group. The CRE group ingested 20 g/day of CRE for 8 days, while the PLA group ingested 20 g/day of maltodextrin for the same period. On the sixth and eighth days of the loading period, both groups performed a Wingate anaerobic test 1 hr after either CAF (5 mg/kg of body mass; CRE + CAF and PLA + CAF conditions) or PLA (5 mg/kg of body mass of cellulose; CRE + PLA and PLA + PLA conditions) ingestion. After the loading period, changes in body mass were greater (p < .05) in the CRE (+0.87 ± 0.23 kg) than in the PLA group (+0.13 ± 0.27 kg). In both groups, peak power was higher (p = .01) in the CAF (1,033.4 ± 209.3 W) than in the PLA trial (1,003.3 ± 204.4 W), but mean power was not different between PLA and CAF trials (p > .05). In conclusion, CAF, but not CRE ingestion, increases anaerobic power. Conversely, neither CRE nor CAF has an effect on anaerobic capacity.


Assuntos
Cafeína , Creatina , Humanos , Masculino , Anaerobiose , Cafeína/farmacologia , Estudos Cross-Over , Método Duplo-Cego , Poliésteres
3.
Chem Rev ; 121(3): 1804-1844, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33398986

RESUMO

Life relies on the constant exchange of different forms of energy, i.e., on energy transduction. Therefore, organisms have evolved in a way to be able to harvest the energy made available by external sources (such as light or chemical compounds) and convert these into biological useable energy forms, such as the transmembrane difference of electrochemical potential (ΔµÌƒ). Membrane proteins contribute to the establishment of ΔµÌƒ by coupling exergonic catalytic reactions to the translocation of charges (electrons/ions) across the membrane. Irrespectively of the energy source and consequent type of reaction, all charge-translocating proteins follow two molecular coupling mechanisms: direct- or indirect-coupling, depending on whether the translocated charge is involved in the driving reaction. In this review, we explore these two coupling mechanisms by thoroughly examining the different types of charge-translocating membrane proteins. For each protein, we analyze the respective reaction thermodynamics, electron transfer/catalytic processes, charge-translocating pathways, and ion/substrate stoichiometries.


Assuntos
Proteínas de Membrana/metabolismo , Termodinâmica , Técnicas Eletroquímicas , Transporte de Elétrons , Proteínas de Membrana/química
4.
Mol Ecol ; 31(18): 4797-4817, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35869812

RESUMO

Geologically recent radiations can shed light on speciation processes, but incomplete lineage sorting and introgressive gene flow render accurate evolutionary reconstruction and interpretation challenging. Independently evolving metapopulations of low dispersal taxa may provide an additional level of phylogeographic information, given sufficiently broad sampling and genome-wide sequencing. Evolution in the marine brown algal genus Fucus in the south-eastern North Atlantic was shaped by Quaternary climate-driven range shifts. Over this timescale, divergence and speciation occurred against a background of expansion-contraction cycles from multiple refugia, together with mating-system shifts from outcrossing (dioecy) to selfing hermaphroditism. We tested the hypothesis that peripheral isolation of range edge (dioecious) F. vesiculosus led to parapatric speciation and radiation of hermaphrodite lineages. Species tree methods using 876 single-copy nuclear genes and extensive geographic coverage produced conflicting topologies with respect to geographic clades of F. vesiculosus. All methods, however, revealed a new and early diverging hermaphrodite species, Fucus macroguiryi sp. nov. Both the multispecies coalescent and polymorphism-aware models (in contrast to concatenation) support sequential paraphyly in F. vesiculosus resulting from distinct evolutionary processes. Our results support (1) peripheral isolation of the southern F. vesiculosus clade prior to parapatric speciation and radiation of hermaphrodite lineages-a "low-latitude species pump". (2) Directional introgressive gene flow into F. vesiculosus around the present-day secondary contact zone (sympatric-allopatric boundary) between dioecious/hermaphrodite lineages as hermaphrodites expanded northwards, supported by concordance analysis and statistical tests of introgression. (3) Species boundaries in the extensive sympatric range are probably maintained by reproductive system (selfing in hermaphrodites) and reinforcement.


Assuntos
Fucus , Fluxo Gênico , Fucus/genética , Filogenia , Filogeografia , Reprodução/genética , Simpatria
5.
Crit Rev Food Sci Nutr ; : 1-13, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35894639

RESUMO

While the effects of caffeine ingestion on endurance performance are well known, its effects on cardiopulmonary responses during a maximal graded exercise test have been less explored. This study systematically reviewed and meta-analyzed studies investigating the effects of caffeine ingestion on cardiopulmonary responses during a maximal graded exercise test. A search was performed in four databases, and study quality was assessed using the PEDro scale. Data reported by the selected studies were pooled using random-effects meta-analysis, with selected moderator effects assessed via meta-regression. Twenty-one studies with good and excellent methodological quality were included in this review. Compared to placebo, caffeine increased peak minute ventilation (SMD = 0.33; p = 0.01) and time to exhaustion (SMD = 0.41; p = 0.01). However, meta-regression showed no moderating effects of dosage and timing of caffeine ingestion, stage length, or total length of GXT (all p > 0.05). Caffeine ingestion did not affect peak oxygen uptake (SMD = 0.13; p = 0.42), peak heart rate (SMD = 0.27; p = 0.07), peak blood lactate concentration (SMD = 0.60; p = 0.09), peak tidal volume (SMD = 0.10; p = 0.69), peak breathing frequency (SMD =0.20; p = 0.23), or peak power output (SMD = 0.22; p = 0.28). The results of this systematic review with meta-analysis suggest that caffeine increases time to exhaustion and peak minute ventilation among the cardiopulmonary variables assessed during GXT.

6.
Eur J Appl Physiol ; 122(2): 371-382, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34739602

RESUMO

PURPOSE: The study aimed to assess the metabolic impact of elite Brazilian U-20 players using the rating of perceived exertion scale (RPE) to discriminate metabolomics sensitivity post-two soccer games separated by a short recovery interval. METHODS: Urine was collected immediately and then 20 h after two soccer matches of elite Brazilian U-20 players. RPE was collected after games. The spectra were pre-processed using TopSpin®3.2 software. Chenomx®software was used to identify metabolites in the urine through the available database. RESULTS: The results showed that the metabolic pathways related to energy production, cellular damage, and organic stresses were changed immediately after the game. 20 h after the games, antioxidant and anti-inflammatory pathways related to cell recovery were identified (e.g., gallic acid, ascorbate, and betaine). The matrix of positive correlations between metabolites was more predominant and stronger after game 2 than game 1. T-distribution registered metabolites discriminated below and above 7 on the RPE scale. Athletes with higher RPE values showed a high metabolite profile related to muscle damage (e.g., creatine, creatinine, and glycine) and energy production (e.g., creatine, formate, pyruvate, 1,3 dihydroxyacetone) 20 h post-soccer match. There was a different metabolic profile between athletes with higher and lower RPE values. CONCLUSION: Metabolomics analysis made it possible to observe the metabolic impacts of energy production and muscular damage. RPE identified internal load changes within the group as a result of match intensity in soccer. The correlation matrix indicated a greater predominance of positive and strong correlations between metabolites in the second game compared to the first game.


Assuntos
Desempenho Atlético/fisiologia , Metabolômica , Esforço Físico/fisiologia , Futebol/fisiologia , Biomarcadores/urina , Brasil , Humanos , Masculino , Adulto Jovem
7.
J Chem Inf Model ; 61(1): 335-346, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33400529

RESUMO

Nucleotides are structural units relevant not only in nucleic acids but also as substrates or cofactors in key biochemical reactions. The size- and timescales of such nucleotide-protein interactions fall well within the scope of coarse-grained molecular dynamics, which holds promise of important mechanistic insight. However, the lack of specific parameters has prevented accurate coarse-grained simulations of protein interactions with most nucleotide compounds. In this work, we comprehensively develop coarse-grained parameters for key metabolites/cofactors (FAD, FMN, riboflavin, NAD, NADP, ATP, ADP, AMP, and thiamine pyrophosphate) in different oxidation and protonation states as well as for smaller molecules derived from them (among others, nicotinamide, adenosine, adenine, ribose, thiamine, and lumiflavin), summing up a total of 79 different molecules. In line with the Martini parameterization methodology, parameters were tuned to reproduce octanol-water partition coefficients. Given the lack of existing data, we set out to experimentally determine these partition coefficients, developing two methodological approaches, based on 31P-NMR and fluorescence spectroscopy, specifically tailored to the strong hydrophilicity of most of the parameterized compounds. To distinguish the partition of each relevant protonation species, we further potentiometrically characterized the protonation constants of key molecules. This work successfully builds a comprehensive and relevant set of computational models that will boost the biochemical application of coarse-grained simulations. It does so based on the measurement of partition and acid-base physicochemical data that, in turn, covers important gaps in nucleotide characterization.


Assuntos
Simulação de Dinâmica Molecular , Nucleotídeos , Interações Hidrofóbicas e Hidrofílicas , Octanóis , Água
8.
Sensors (Basel) ; 21(22)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34833810

RESUMO

This article presents an approach to autonomous flight planning of Unmanned Aerial Vehicles (UAVs)-Drones as data collectors to the Internet of Things (IoT). We have proposed a model for only one aircraft, as well as for multiple ones. A clustering technique that extends the scope of the number of IoT devices (e.g., sensors) visited by UAVs is also addressed. The flight plan generated from the model focuses on preventing breakdowns due to a lack of battery charge to maximize the number of nodes visited. In addition to the drone autonomous flight planning, a data storage limitation aspect is also considered. We have presented the energy consumption of drones based on the aerodynamic characteristics of the type of aircraft. Simulations show the algorithm's behavior in generating routes, and the model is evaluated using a reliability metric.

9.
New Phytol ; 222(1): 565-575, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30411803

RESUMO

Unraveling the phylogenetic relationships between the four major lineages of terrestrial plants (mosses, liverworts, hornworts, and vascular plants) is essential for an understanding of the evolution of traits specific to land plants, such as their complex life cycles, and the evolutionary development of stomata and vascular tissue. Well supported phylogenetic hypotheses resulting from different data and methods are often incongruent due to processes of nucleotide evolution that are difficult to model, for example substitutional saturation and composition heterogeneity. We reanalysed a large published dataset of nuclear data and modelled these processes using degenerate-codon recoding and tree-heterogeneous composition substitution models. Our analyses resolved bryophytes as a monophyletic group and showed that the nonnonmonophyly of the clade that is supported by the analysis of nuclear nucleotide data is due solely to fast-evolving synonymous substitutions. The current congruence among phylogenies of both nuclear and chloroplast analyses lent considerable support to the conclusion that the bryophytes are a monophyletic group. An initial split between bryophytes and vascular plants implies that the bryophyte life cycle (with a dominant gametophyte nurturing an unbranched sporophyte) may not be ancestral to all land plants and that stomata are likely to be a symplesiomorphy among embryophytes.


Assuntos
Briófitas/metabolismo , Proteínas Nucleares/metabolismo , Filogenia , Aminoácidos/genética , Nucleotídeos/genética
10.
Biochim Biophys Acta Bioenerg ; 1859(9): 742-753, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29684324

RESUMO

Hydrogen sulfide (H2S) is a versatile molecule with different functions in living organisms: it can work as a metabolite of sulfur and energetic metabolism or as a signaling molecule in higher Eukaryotes. H2S is also highly toxic since it is able to inhibit heme cooper oxygen reductases, preventing oxidative phosphorylation. Due to the fact that it can both inhibit and feed the respiratory chain, the immediate role of H2S on energy metabolism crucially relies on its bioavailability, meaning that studying the central players involved in the H2S homeostasis is key for understanding sulfide metabolism. Two different enzymes with sulfide oxidation activity (sulfide dehydrogenases) are known: flavocytochrome c sulfide dehydrogenase (FCSD), a sulfide:cytochrome c oxidoreductase; and sulfide:quinone oxidoreductase (SQR). In this work we performed a thorough bioinformatic study of SQRs and FCSDs and integrated all published data. We systematized several properties of these proteins: (i) nature of flavin binding, (ii) capping loops and (iii) presence of key amino acid residues. We also propose an update to the SQR classification system and discuss the role of these proteins in sulfur metabolism.


Assuntos
Grupo dos Citocromos c/química , Grupo dos Citocromos c/classificação , Flavina-Adenina Dinucleotídeo/metabolismo , Oxirredutases/química , Oxirredutases/classificação , Quinona Redutases/química , Quinona Redutases/classificação , Sulfetos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/classificação , Proteínas de Bactérias/metabolismo , Biocatálise , Grupo dos Citocromos c/metabolismo , Cinética , Modelos Moleculares , Oxirredução , Oxirredutases/metabolismo , Conformação Proteica , Quinona Redutases/metabolismo , Relação Estrutura-Atividade
11.
BMC Evol Biol ; 18(1): 9, 2018 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-29374461

RESUMO

BACKGROUND: Whole genome duplication plays a central role in plant evolution. There are two main classes of polyploid formation: autopolyploids which arise within one species by doubling of similar homologous genomes; in contrast, allopolyploidy (hybrid polyploidy) arise via hybridization and subsequent doubling of nonhomologous (homoeologous) genomes. The distinction between polyploid origins can be made using gene phylogenies, if alleles from each genome can be correctly retrieved. We examined whether two closely related tetraploid Mediterranean shrubs (Medicago arborea and M. strasseri) have an allopolyploid origin - a question that has remained unsolved despite substantial previous research. We sequenced and analyzed ten low-copy nuclear genes from these and related species, phasing all alleles. To test the efficacy of allele phasing on the ability to recover the evolutionary origin of polyploids, we compared these results to analyses using unphased sequences. RESULTS: In eight of the gene trees the alleles inferred from the tetraploids formed two clades, in a non-sister relationship. Each of these clades was more closely related to alleles sampled from other species of Medicago, a pattern typical of allopolyploids. However, we also observed that alleles from one of the remaining genes formed two clades that were sister to one another, as is expected for autopolyploids. Trees inferred from unphased sequences were very different, with the tetraploids often placed in poorly supported and different positions compared to results obtained using phased alleles. CONCLUSIONS: The complex phylogenetic history of M. arborea and M. strasseri is explained predominantly by shared allotetraploidy. We also observed that an increase in woodiness is correlated with polyploidy in this group of species and present a new possibility that woodiness could be a transgressive phenotype. Correctly phased homoeologues are likely to be critical for inferring the hybrid origin of allopolyploid species, when most genes retain more than one homoeologue. Ignoring homoeologous variation by merging the homoeologues can obscure the signal of hybrid polyploid origins and produce inaccurate results.


Assuntos
Alelos , Medicago/genética , Poliploidia , Sequência de Bases , Evolução Molecular , Genes de Plantas , Hibridização Genética , Filogenia , Densidade Demográfica , Especificidade da Espécie
12.
Sensors (Basel) ; 18(11)2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30445730

RESUMO

The massive dissemination of smart devices in current markets provides innovative technologies that can be used in energy management systems. Particularly, smart plugs enable efficient remote monitoring and control capabilities of electrical resources at a low cost. However, smart plugs, besides their enabling capabilities, are not able to acquire and communicate information regarding the resource's context. This paper proposes the EnAPlug, a new environmental awareness smart plug with knowledge capabilities concerning the context of where and how users utilize a controllable resource. This paper will focus on the abilities to learn and to share knowledge between different EnAPlugs. The EnAPlug is tested in two different case studies where user habits and consumption profiles are learned. A case study for distributed resource optimization is also shown, where a central heater is optimized according to the shared knowledge of five EnAPlugs.

13.
Molecules ; 23(4)2018 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-29584709

RESUMO

There is an urgent need for the discovery of new antileishmanial drugs with a new mechanism of action. Type 2 NADH dehydrogenase from Leishmania infantum (LiNDH2) is an enzyme of the parasite's respiratory system, which catalyzes the electron transfer from NADH to ubiquinone without coupled proton pumping. In previous studies of the related NADH: ubiquinone oxidoreductase crystal structure from Saccharomyces cerevisiae, two ubiquinone-binding sites (UQI and UQII) were identified and shown to play an important role in the NDH-2-catalyzed oxidoreduction reaction. Based on the available structural data, we developed a three-dimensional structural model of LiNDH2 using homology detection methods and performed an in silico virtual screening campaign to search for potential inhibitors targeting the LiNDH2 ubiquinone-binding site 1-UQI. Selected compounds displaying favorable properties in the computational screening experiments were assayed for inhibitory activity in the structurally similar recombinant NDH-2 from S. aureus and leishmanicidal activity was determined in the wild-type axenic amastigotes and promastigotes of L. infantum. The identified compound, a substituted 6-methoxy-quinalidine, showed promising nanomolar leishmanicidal activity on wild-type axenic promastigotes and amastigotes of L. infantum and the potential for further development.


Assuntos
Antiprotozoários/química , Leishmania infantum/enzimologia , NADH Desidrogenase/metabolismo , Quinaldinas/química , Antiprotozoários/farmacologia , Domínio Catalítico/efeitos dos fármacos , Simulação por Computador , Avaliação Pré-Clínica de Medicamentos , Leishmania infantum/efeitos dos fármacos , Modelos Moleculares , NADH Desidrogenase/química , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Quinaldinas/farmacologia , Homologia Estrutural de Proteína , Relação Estrutura-Atividade
14.
Biochim Biophys Acta Bioenerg ; 1858(10): 823-832, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28801048

RESUMO

Type II NADH:quinone oxidoreductases (NDH-2s) are membrane bound enzymes that deliver electrons to the respiratory chain by oxidation of NADH and reduction of quinones. In this way, these enzymes also contribute to the regeneration of NAD+, allowing several metabolic pathways to proceed. As for the other members of the two-Dinucleotide Binding Domains Flavoprotein (tDBDF) superfamily, the enzymatic mechanism of NDH-2s is still little explored and elusive. In this work we addressed the role of the conserved glutamate 172 (E172) residue in the enzymatic mechanism of NDH-2 from Staphylococcus aureus. We aimed to test our earlier hypothesis that E172 plays a key role in proton transfer to allow the protonation of the quinone. For this we performed a complete biochemical characterization of the enzyme's variants E172A, E172Q and E172S. Our steady state kinetic measurements show a clear decrease in the overall reaction rate, and our substrate interaction studies indicate the binding of the two substrates is also affected by these mutations. Interestingly our fast kinetic results show quinone reduction is more affected than NADH oxidation. We have also determined the X-ray crystal structure of the E172S mutant (2.55Ǻ) and compared it with the structure of the wild type (2.32Ǻ). Together these results support our hypothesis for E172 being of central importance in the catalytic mechanism of NDH-2, which may be extended to other members of the tDBDF superfamily.


Assuntos
Proteínas de Bactérias/metabolismo , Benzoquinonas/metabolismo , Ácido Glutâmico/metabolismo , NADH Desidrogenase/metabolismo , NAD/metabolismo , Quinona Redutases/metabolismo , Staphylococcus aureus/metabolismo , Oxirredução , Ligação Proteica/fisiologia
15.
Biochim Biophys Acta ; 1857(8): 1039-1067, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27044012

RESUMO

Acquisition of energy is central to life. In addition to the synthesis of ATP, organisms need energy for the establishment and maintenance of a transmembrane difference in electrochemical potential, in order to import and export metabolites or to their motility. The membrane potential is established by a variety of membrane bound respiratory complexes. In this work we explored the diversity of membrane respiratory chains and the presence of the different enzyme complexes in the several phyla of life. We performed taxonomic profiles of the several membrane bound respiratory proteins and complexes evaluating the presence of their respective coding genes in all species deposited in KEGG database. We evaluated 26 quinone reductases, 5 quinol:electron carriers oxidoreductases and 18 terminal electron acceptor reductases. We further included in the analyses enzymes performing redox or decarboxylation driven ion translocation, ATP synthase and transhydrogenase and we also investigated the electron carriers that perform functional connection between the membrane complexes, quinones or soluble proteins. Our results bring a novel, broad and integrated perspective of membrane bound respiratory complexes and thus of the several energetic metabolisms of living systems. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi.


Assuntos
Archaea/metabolismo , Proteínas Arqueais/metabolismo , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Membrana Celular/metabolismo , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Archaea/genética , Proteínas Arqueais/genética , Bactérias/genética , Proteínas de Bactérias/genética , Membrana Celular/química , Transporte de Elétrons , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , ATPases Mitocondriais Próton-Translocadoras/genética , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Oxirredução , Oxirredutases/genética , Oxirredutases/metabolismo , Quinona Redutases/genética , Quinona Redutases/metabolismo , Quinonas/metabolismo
16.
Int J Sports Med ; 38(5): 378-383, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28255967

RESUMO

This study aims to propose and validate the tethered swimming lactate minimum test (TSLacmin) estimating aerobic and anaerobic capacity in one single test session, using force as measurement parameter. 6 male and 6 female young swimmers (age=15.7±1.1 years; height=173.3±9.5 cm; weight=66.1±9.5 kg) performed 4 sessions comprising i) an all-out 30 s test and incremental test (TSLacmin); ii) 30 min of tethered swimming at constant intensity (2 sessions); iii) free-swimming time trials used to calculate critical velocity. Tethered swimming sessions used an acquisition system enabling maximum (Fmax) and mean (Fmean) force measurement and intensity variation. The tethered all-out test lasting 30 s resulted in hyperlactatemia of 7.9±2.0 mmol·l-1. TSLacmin presented a 100% success applicability rate, which is equivalent to aerobic capacity in 75% of cases. TSLacmin intensity was 37.7±7.3 N, while maximum force in the all-out test was 105±27 N. Aerobic and anaerobic TSLacmin parameters were significantly related to free-swimming performance (r=-0.67 for 100 m and r=-0.80 for 200 m) and critical velocity (r=0.80). TSLacmin estimates aerobic capacity in most cases, and both aerobic and anaerobic force parameters are well related to critical velocity and free swimming performance.


Assuntos
Limiar Anaeróbio/fisiologia , Teste de Esforço/métodos , Ácido Láctico/sangue , Natação/fisiologia , Adolescente , Feminino , Humanos , Masculino
17.
Environ Microbiol ; 18(12): 4697-4709, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27105286

RESUMO

Type II NADH:quinone oxidoreductases (NDH-2s) are membrane proteins, crucial for the catabolic metabolism, because they contribute to the maintenance of the NADH/NAD+ balance. In several pathogenic bacteria and protists, NDH-2s are the only enzymes performing respiratory NADH:quinone oxidoreductase activity. For this reason and for being considered absent in mammals, NDH-2s were proposed as suitable targets for novel antimicrobial therapies. We selected all sequences of genes encoding NDH-2s from fully sequenced genomes present in the KEGG database. These genes were present in 61% of the 1805 species belonging to Eukarya (83%), Bacteria (60%) and Archaea (32%). Notably sequences from mammal species including humans were retrieved in our selection as NDH-2s. The data obtained and the already available information allowed systematizing several properties of NDH-2s: (i) the existence of additional sequence motifs with putative regulatory functions, (ii) specificity towards NADH or NADPH and (iii) the type of quinone binding motif. We observed that NDH-2 family distribution is not congruent with the taxonomic tree, suggesting different origins for the eukaryotic sequences and possible lateral gene transfer among prokaryotes. We note the absence of genes coding for NDH-2 in anaerobic phyla and the presence of multiple copies in several genomes, specifically in cyanobacteria. These observations inspired us to propose a metabolic hypothesis for the appearance of NDH-2s.


Assuntos
Cianobactérias/metabolismo , Evolução Molecular , NADH NADPH Oxirredutases/metabolismo , Archaea/enzimologia , Archaea/genética , Archaea/metabolismo , Sequência de Bases , Cianobactérias/enzimologia , Cianobactérias/genética , NADP/metabolismo , Oxirredução , Filogenia , Células Procarióticas/enzimologia , Células Procarióticas/metabolismo , Quinonas/metabolismo
18.
Syst Biol ; 64(3): 448-71, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25604357

RESUMO

There is a rising awareness that species trees are best inferred from multiple loci while taking into account processes affecting individual gene trees, such as substitution model error (failure of the model to account for the complexity of the data) and coalescent stochasticity (presence of incomplete lineage sorting [ILS]). Although most studies have been carried out in the context of dichotomous species trees, these processes operate also in more complex evolutionary histories involving multiple hybridizations and polyploidy. Recently, methods have been developed that accurately handle ILS in allopolyploids, but they are thus far restricted to networks of diploids and tetraploids. We propose a procedure that improves on this limitation by designing a workflow that assigns homoeologs to hypothetical diploid ancestral genomes prior to genome tree construction. Conflicting assignment hypotheses are evaluated against substitution model error and coalescent stochasticity. Incongruence that cannot be explained by stochastic mechanisms needs to be explained by other processes (e.g., homoploid hybridization or paralogy). The data can then be filtered to build multilabeled genome phylogenies using inference methods that can recover species trees, either in the face of substitution model error and coalescent stochasticity alone, or while simultaneously accounting for hybridization. Methods are already available for folding the resulting multilabeled genome phylogeny into a network. We apply the workflow to the reconstruction of the reticulate phylogeny of the plant genus Fumaria (Papaveraceae) with ploidal levels ranging from 2[Formula: see text] to 14[Formula: see text]. We describe the challenges in recovering nuclear NRPB2 homoeologs in high ploidy species while combining in vivo cloning and direct sequencing techniques. Using parametric bootstrapping simulations we assign nuclear homoeologs and chloroplast sequences (four concatenated loci) to their common hypothetical diploid ancestral genomes. As these assignments hinge on effective population size assumptions, we investigate how varying these assumptions impacts the recovered multilabeled genome phylogeny.


Assuntos
Classificação/métodos , Fumaria/classificação , Fumaria/genética , Genoma de Planta/genética , Filogenia , Poliploidia , Cloroplastos/genética , Homologia de Sequência
19.
Data Brief ; 54: 110540, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38868387

RESUMO

We present a dataset containing nuclear and chloroplast sequences for 71 species in genus Medicago (Fabaceae), as well as for 8 species in genera Melilotus and Trigonella. Sequence data for a total of 130 samples was obtained with high-throughput sequencing of enriched genomic DNA libraries targeting 61 single-copy nuclear genes from across the Medicago truncatula genome. Chloroplast sequence reads were also generated, allowing for the recovery of chloroplast genome sequences for all 130 samples. A fully-resolved phylogenetic tree was inferred from the chloroplast dataset using maximum-likelihoood methods. More than 80% of accepted Medicago species are represented in this dataset, including three subspecies of Medicago sativa (alfalfa). These data can be further utilised for phylogenetic analyses in Medicago and related genera, but also for probe and primer design and plant breeding studies.

20.
Res Q Exerc Sport ; : 1-8, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38271741

RESUMO

Background: The benefits of caffeine to physical performance have been extensively demonstrated, however, it has recently been speculated that there is an effect of the administration route on its effectiveness. Purpose: The current study investigated the effect of caffeine mouth rinse in isolation or combined with ingestion on performance in a 30-minute constant-load exercise followed by a 10-km cycling time trial. Methods: Ten physically active men performed a 30-minute constant-load exercise at 50% of the graded test Wmax, followed by a 10-km cycling time trial. Before and at the middle points of the constant-load exercise and 10-km cycling time trial, the following conditions were administered: PLA (cellulose ingestion plus mouth rinsing with magnesium sulfate), ING (5 mg.kg-1 of caffeine ingestion plus mouth rinsing with magnesium sulfate), MR (cellulose ingestion plus mouth rinsing with 1.2% caffeine), and COMB (5 mg.kg-1 of caffeine ingestion plus mouth rinsing with 1.2% caffeine). Results: During the 30-minute constant-load exercise, COMB presented a lower rating of perceived exertion (RPE) than MR (p = .04). For the 10-km time trial, the COMB was faster than MR (MR = 1363 ± 345 vs. COMB = 1291 ± 308s, Δ% = 5.57, p = .05). Mean power output was higher in COMB than PLA, ING, and MR (234 ± 15 vs. 169 ± 29, 148 ± 11, and 145 ± 12 W, respectively). There were no differences between conditions for heart rate and RPE during the 10-km time trial. Conclusion: In summary, caffeine mouth rinsing potentiated the effects of caffeine ingestion during the 10-km time trial compared to caffeine mouth rinsing alone.

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