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1.
Chem Commun (Camb) ; 60(55): 7037-7040, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38895750

RESUMO

A new photochemical CSTR system capable of handling solids in scaled continuous processes is presented. High-power UV-LEDs are integrated in these CSTRs containing an insoluble base that aids in generating pyrazolines via cycloaddition between alkenes and in situ generated diazo species. Contrary to reported batch methods product degradation via ring contraction is suppressed whilst generating gram quantities of spirocyclic pyrazolines.

3.
PLoS One ; 18(7): e0288541, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37450424

RESUMO

Physical literacy is a multidimensional construct that has been defined and interpreted in various ways, one of the most common being "the motivation, confidence, physical competence, knowledge and understanding to maintain physical activity throughout the life course". Although its improvement can positively affect many behavioral, psychological, social, and physical variables, debate remains over an appropriate method of collecting empirical physical literacy data. This systematic review sought to identify and critically evaluate all primary studies (published and unpublished, regardless of design or language) that assessed physical literacy in adults or have proposed measurement criteria. Relevant studies were identified by searching four databases (Pubmed, SportDiscus, APA PsycINFO, Web of Science), scanning reference lists of included articles, and manual cross-referencing of bibliographies cited in prior reviews. The final search was concluded on July 15, 2022. Thirty-one studies, published from 2016 to 2022, were analyzed. We found seven instruments measuring physical literacy in adults, of which six were questionnaires. The Perceived Physical Literacy Instrument was the first developed for adults and the most adopted. The included studies approached physical literacy definition in two ways: by pre-defining domains and assessing them discretely (through pre-validated or self-constructed instruments) and by defining domains as sub-scales after factorial analyses. We found a fair use of objective and subjective measures to assess different domains. The wide use of instruments developed for other purposes in combined assessments suggests the need for further instrument development and the potential oversimplification of the holistic concept, which may not result in a better understanding of physical literacy. Quality and usability characteristics of measurements were generally insufficiently reported. This lack of data makes it impossible to compare and make robust conclusions. We could not identify if any of the existing physical literacy assessments for adults is appropriate for large-scale/epidemiological studies.


Assuntos
Exercício Físico , Letramento em Saúde , Letramento em Saúde/métodos , Inquéritos e Questionários , Processos Mentais
4.
Sports (Basel) ; 12(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38251280

RESUMO

The "zero point" method allows for lower intensities for an exercise session without impairing the total training volume. This study aimed to compare the effects of the "zero point" versus the traditional method on muscle responses and muscle damage in trained men. Fifteen experienced men (age: 27.7 ± 6.4 years; body mass: 78.4 ± 11.4 kg; height: 174.8 ± 4.9 cm; experience: 5.86 ± 4.7 years; relative bench press strength: 1.38 ± 0.17 kg·kg-1) were subjected to two exercise protocols in a randomized order and separated by a week. The traditional and "zero point" methods were applied in the bench press, with loads of 70% and 50% of one repetition maximum (1RM), respectively, for 10 sets until concentric failure, with 3-min intervals between sets. The zero point method displayed a higher number of repetitions and time under tension than the traditional method, with no difference in the total training volume, echo intensity, algometry, lactate, and myoglobin. For the muscle thickness, no differences between the groups were presented, except for the deltoid muscle thickness, in which a higher post-training volume was observed compared to traditional training. The "zero point" method increases the demand on the deltoid muscles in the bench press exercise, but not on the pectoralis and triceps brachii.

5.
Nat Commun ; 13(1): 6147, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36257941

RESUMO

Photocatalytic hydrogen atom transfer (HAT) processes have been the object of numerous studies showcasing the potential of the homogeneous photocatalyst tetrabutylammonium decatungstate (TBADT) for the functionalization of C(sp3)-H bonds. However, to translate these studies into large-scale industrial processes, careful considerations of catalyst loading, cost, and removal are required. This work presents organic solvent nanofiltration (OSN) as an answer to reduce TBADT consumption, increase its turnover number and lower its concentration in the product solution, thus enabling large-scale photocatalytic HAT-based transformations. The operating parameters for a suitable membrane for TBADT recovery in acetonitrile were optimized. Continuous photocatalytic C(sp3)-H alkylation and amination reactions were carried out with in-line TBADT recovery via two OSN steps. Promisingly, the observed product yields for the reactions with in-line catalyst recycling are comparable to those of reactions performed with pristine TBADT, therefore highlighting that not only catalyst recovery (>99%, TON > 8400) is a possibility, but also that it does not happen at the expense of reaction performance.

6.
ACS Catal ; 12(18): 11216-11225, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36158902

RESUMO

A strategy for both cross-electrophile coupling and 1,2-dicarbofunctionalization of olefins has been developed. Carbon-centered radicals are generated from alkyl bromides by merging benzophenone hydrogen atom transfer (HAT) photocatalysis and silyl radical-induced halogen atom transfer (XAT) and are subsequently intercepted by a nickel catalyst to forge the targeted C(sp3)-C(sp2) and C(sp3)-C(sp3) bonds. The mild protocol is fast and scalable using flow technology, displays broad functional group tolerance, and is amenable to a wide variety of medicinally relevant moieties. Mechanistic investigations reveal that the ketone catalyst, upon photoexcitation, is responsible for the direct activation of the silicon-based XAT reagent (HAT-mediated XAT) that furnishes the targeted alkyl radical and is ultimately involved in the turnover of the nickel catalytic cycle.

7.
Front Physiol ; 13: 899652, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060700

RESUMO

The establishment of fatigue following the acute exercise stimulus is a complex and multi-factorial process, that might arise due to a range of distinct physiological mechanisms. However, a practical method of assessing CrossFit® athletes' recovery status has been neglected entirely in real-world sporting practice. The study describes the acute and delayed time course of recovery following the CrossFit® Benchmark Workout Karen. Eight trained men (28.4 ± 6.4 years; 1RM back squat 139.1 ± 26.0 kg) undertook the Karen protocol. The protocol consists of 150 Wall Balls (9 kg), aiming to hit a target 3 m high. Countermovement jump height (CMJ), creatine kinase (CK), and perceived recovery status scale (PRS) (general, lower and upper limbs) were assessed pre, post-0h, 24, 48 and 72 h after the session. The creatine kinase concentration 24 h after was higher than pre-exercise (338.4 U/L vs. 143.3 U/L; p = 0.040). At 48h and 72 h following exercise, CK concentration had returned to baseline levels (p > 0.05). The general, lower and upper limbs PRS scores were lower in the 24-h post-exercise compared to pre-exercise (general PRS: 4.7 ± 1.5 and 7.7 ± 1.7; p = 0.013; upper limbs PRS: 6.6 ± 1.3 and 7.5 ± 1.3; p = 0.037; lower limbs PRS: 3.9 ± 2.5 and 7.3 ± 0.1; p = 0.046). Our findings provide insights into the fatigue profile and recovery in acute CrossFit® and can be useful to coaches and practitioners when planning training programs. Moreover, recovery status can be useful to optimize training monitoring and to minimize the potential detrimental effects associated with the performance of repeated high-intensity sessions of CrossFit®.

8.
Chem Sci ; 13(24): 7325-7331, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35799818

RESUMO

The late-stage introduction of allyl groups provides an opportunity to synthetic organic chemists for subsequent diversification, furnishing a rapid access to new chemical space. Here, we report the development of a modular synthetic sequence for the allylation of strong aliphatic C(sp3)-H bonds. Our sequence features the merger of two distinct steps to accomplish this goal, including a photocatalytic Hydrogen Atom Transfer and an ensuing Horner-Wadsworth-Emmons (HWE) reaction. This practical protocol enables the modular and scalable allylation of valuable building blocks and has been applied to structurally complex molecules.

9.
J Pept Sci ; 28(12): e3441, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35785412

RESUMO

As peptides gained interest as new drugs in the past years, their synthetic routes had been the subject of review and improvement. Fmoc/tBu-based solid-phase peptide synthesis (SPPS) is the most convenient technique, and the implementation in continuous flow has allowed for single-pass coupling and deprotection reactions. The focus of this research is to evaluate the relationship between undesired solvent-promoted reactions and final crude purity, by studying volume changes of a variable bed flow reactor through the synthesis. Based on the temperature, typical solvents for SPPS such as dimethylformamide (DMF) or N-methyl-2-pyrrolidone (NMP) can cause unwanted Fmoc removal during wash steps. It was found that for every millilitre of DMF used at 80°C, up to 1 µmol of Fmoc-protected peptide is deprotected, leading to additional impurities. This effect can, however, be minimised by adding additives such as HOBt, which reduces such unwanted deprotection to just 0.1 µmol/ml.


Assuntos
Peptídeos , Técnicas de Síntese em Fase Sólida , Técnicas de Síntese em Fase Sólida/métodos , Dimetilformamida , Solventes , Fluorenos
10.
BMC Sports Sci Med Rehabil ; 14(1): 22, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35135608

RESUMO

BACKGROUND: To investigate the time-course effects of a self-regulated training session (performed at an rating perceived exertion of 6/10), all-out session, and a control session on the metabolic, hormonal, and brain derived neurotrophic factor (BDNF) responses in Functional-Fitness (FFT) participants. METHODS: In a randomized, crossover fashion, eight healthy males (age 28.1 ± 5.4 years old; body mass 77.2 ± 4.4 kg; VO2max: 52.6 ± 4.6 mL.(kg.min)-1; 2000 m rowing test 7.35 ± 0.18 min; 1RM back squat 135.6 ± 21.9 kg) performed a FFT session under two different conditions: all-out, or with the intensity controlled to elicit an rating perceived exertion (RPE) of 6 in the Borg 10-point scale (RPE6). A control session (no exercise) was also completed. Metabolic (lactate and creatine kinase), hormonal (testosterone and cortisol), and BDNF responses were assessed pre, post-0 h, 1 h, 2 h and 24 h after the sessions. RESULTS: Creatine kinase concentrations were significantly higher (p ≤ 0.05) after 24 h for both training sessions. Total and free testosterone concentrations were lower post-2 h for all-out when compared to the RPE6 session (p ≤ 0.05). Serum cortisol concentration increased post-0 h (p = 0.011) for RPE6 and post-0 h (p = 0.003) and post-1 h (p = 0.030) for all-out session when comparing to baseline concentrations. BDNF was significantly higher (p = 0.002) post-0 h only for the all-out session when compared to baseline. A positive correlation between blood lactate concentrations and BDNF (r = 0.51; p = 0.01) was found for both effort interventions. CONCLUSIONS: A single FFT session when performed in all-out format acutely increases the concentrations of serum BDNF. However, physiological stress markers show that the all-out session requires a longer recovery period when compared to the RPE6 protocol. These findings can be helpful to coaches and practitioners design FFT session.

11.
Sports (Basel) ; 9(7)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34357932

RESUMO

This study analyzed the relationship between anthropometric measures, cardiorespiratory capacity, strength, power, and local muscle endurance with performance in the CrossFit® Open 2020. For this, 17 volunteers (6 women) (29.0 ± 7.2 years) completed, on separate weeks, tests for body composition (dual-energy X-ray absorptiometry), maximal oxygen consumption (2 km row test), muscle strength (one repetition maximum (1 RM) back and front squat, isometric peak torque), muscle power (1 RM snatch and clean and jerk) and muscle endurance (Tibana test), which were compared with performance during the CrossFit® Open 2020. Specific tests of localized muscular endurance and muscle strength had the strongest relationship with performance in the CrossFit® Open 2020. On the other hand, the percentage of fat and cardiorespiratory capacity were not significantly correlated with CrossFit® Open 2020 workout performance. Coaches and practitioners should therefore utilize these findings to assess physical fitness and organize the distribution of the training session based on less developed physical needs, in order to ensure an appropriate physiological adaptation for a given competition.

12.
Sci Rep ; 11(1): 13118, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162915

RESUMO

The aim of the study was to evaluate and compare the maximal oxygen uptake ([Formula: see text]O2max) achieved during incremental and decremental protocols in highly trained athletes. Nineteen moderate trained runners and rowers completed, on separate days, (i) an initial incremental [Formula: see text]O2max test (INC) on a treadmill, followed by a verification phase (VER); (ii) a familiarization of a decremental test (DEC); (iii) a tailored DEC; (iv) a test with decremental and incremental phases (DEC-INC); (v) and a repeated incremental test (INCF). During each test [Formula: see text]O2, carbon dioxide production, ventilation, heart and breath rates and ratings of perceived exertion were measured. No differences were observed in [Formula: see text]O2max between INC (61.3 ± 5.2 ml kg-1 min-1) and DEC (61.1 ± 5.1 ml kg-1 min-1; average difference of ~ 11.58 ml min-1; p = 0.831), between INC and DEC-INC (60.9 ± 5.3 ml kg-1 min-1; average difference of ~ 4.8 ml min-1; p = 0.942) or between INC and INCF (60.7 ± 4.4 ml kg-1 min-1; p = 0.394). [Formula: see text]O2max during VER (59.8 ± 5.1 ml kg-1 min-1) was 1.50 ± 2.20 ml kg-1 min-1 lower (~ 2.45%; p = 0.008) compared with values measured during INC. The typical error in the test-to-test changes for evaluating [Formula: see text]O2max over the five tests was 2.4 ml kg-1 min-1 (95% CI 1.4-3.4 ml kg-1 min-1). Decremental tests do not elicit higher [Formula: see text]O2max than incremental tests in trained runners and rowers, suggesting that a plateau in [Formula: see text]O2 during the classic incremental and verification tests represents the maximum ceiling of aerobic power.


Assuntos
Teste de Esforço/métodos , Consumo de Oxigênio/fisiologia , Adolescente , Atletas , Frequência Cardíaca/fisiologia , Humanos , Masculino , Esforço Físico/fisiologia , Taxa Respiratória/fisiologia , Corrida/fisiologia , Esportes Aquáticos/fisiologia
13.
Angew Chem Int Ed Engl ; 60(33): 17893-17897, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34060204

RESUMO

Photocatalytic hydrogen atom transfer is a very powerful strategy for the regioselective C(sp3 )-H functionalization of organic molecules. Herein, we report on the unprecedented combination of decatungstate hydrogen atom transfer photocatalysis with the oxidative radical-polar crossover concept to access the direct net-oxidative C(sp3 )-H heteroarylation. The present methodology demonstrates a high functional group tolerance (40 examples) and is scalable when using continuous-flow reactor technology. The developed protocol is also amenable to the late-stage functionalization of biologically relevant molecules such as stanozolol, (-)-ambroxide, podophyllotoxin, and dideoxyribose.

14.
Phys Chem Chem Phys ; 22(38): 21731-21740, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32985625

RESUMO

In the quest for the identification of the light emitter(s) responsible for the firefly bioluminescence, the study of oxyluciferin analogues with controlled chemical and electronic structures is of particular importance. In this article, we report the results of our experimental and computational investigation of the pH-dependent absorption spectra characterizing three analogues bound into the luciferase cavity, together with adenosine-monophosphate (AMP). While the analogue microscopic pKa values do not differ much from their reference values, it turns out that the AMP protonation state is analogue-dependent and never doubly-deprotonated. A careful analysis of the interactions evidences the main role of E344 glutamic acid, as well as the flexibility of the cavity which can accommodate any oxyluciferin analogue. The consideration of the absorption spectra suggests that the oxyluciferin enolate form has to be excluded from the list of the bioluminescence reaction products.


Assuntos
Indóis/química , Luciferases de Vaga-Lume/química , Pirazinas/química , Animais , Domínio Catalítico , Concentração de Íons de Hidrogênio , Luciferases de Vaga-Lume/metabolismo , Espectrometria de Fluorescência
15.
Front Physiol ; 11: 919, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903483

RESUMO

Despite its increase in popularity, little is known about how to best quantify internal training loads from functional fitness training (FFT) sessions. The purpose of this study was to assess which method [training impulse (TRIMP) or session rating of perceived exertion (sRPE)] is more accurate to monitor training loads in FFT. Eight trained males (age 28.1 ± 6.0 years) performed an ALL-OUT FFT session and an intensity-controlled session (RPE of six out of 10). Internal load was determined via Edward's TRIMP (eTRIMP), Bannister's TRIMP (bTRIMP), and sRPE. Heart rate was measured continuously during the session, while blood lactate and rate of perceived exertion were measured at baseline, and immediately and 30 min after the sessions. ALL-OUT blood lactate and RPE were significantly higher immediately and 30 min after the session compared to the RPE6 condition. ALL-OUT training load was significantly different between conditions using bTRIMP (61.1 ± 10.6 vs. 55.7 ± 12.4 AU) and sRPE (91.7 ± 30.4 vs. 42.6 ± 14.9 AU), with sRPE being more sensitive to such differences [p = 0.045, effect size (ES) = 0.76 and p = 0.002, ES = 1.82, respectively]. No differences in the training loads of the different sessions were found using eTRIMP (93.1 ± 9.5 vs. 84.9 ± 13.7 AU, p = 0.085). Only sRPE showed a significant correlation with lactate 30 min post session (p = 0.015; p = 0.596, large). sRPE was more accurate than both TRIMP methods to represent the overall training load of the FFT sessions. While the use of sRPE is advised, further research is necessary to establish its ability to reflect changes in fitness, fatigue, and performance during a period of training.

16.
J Clin Transl Res ; 5(5): 253-259, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32875134

RESUMO

BACKGROUND AND AIM: Growth of elderly population is a worldwide phenomenon that impacts public health. The objective of this study was to compare the pain levels, strength, and quality of life among elderly obese with diabetes or hypertension. MATERIALS AND METHODS: The study cohort comprised 52 obese elderly subjects with hypertension (n = 35) and diabetes (n = 17). The parameters measured were anthropometric features, handgrip strength, visual analog scale for pain, and quality of life using the World Health Organization questionnaire. RESULTS: The level of pain reported by obese hypertensive elderly subjects (5.3 ± 3.4) was lower than reported by obese diabetic elderly subjects (7.4 ± 2.4). Obese hypertensive elderly scored higher on quality of life (sensory functioning and past, present, and future [PPF] activities) than obese diabetic elderly. No differences were observed for the other parameters. Strength, pain, anthropometrics, and hemodynamics were not correlated to quality of life. CONCLUSIONS: Obese elderly diabetics exhibit worse pain scores, sensorial abilities, and PPF activities than obese hypertensive elderly individuals. RELEVANCE FOR PATIENTS: The difference in pain and quality of life aspects between obese elderly individuals with hypertension and diabetes should be accounted for in health-care programs designed for these individuals.

17.
Science ; 369(6499): 92-96, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32631892

RESUMO

Direct activation of gaseous hydrocarbons remains a major challenge for the chemistry community. Because of the intrinsic inertness of these compounds, harsh reaction conditions are typically required to enable C(sp3)-H bond cleavage, barring potential applications in synthetic organic chemistry. Here, we report a general and mild strategy to activate C(sp3)-H bonds in methane, ethane, propane, and isobutane through hydrogen atom transfer using inexpensive decatungstate as photocatalyst at room temperature. The corresponding carbon-centered radicals can be effectively trapped by a variety of Michael acceptors, leading to the corresponding hydroalkylated adducts in good isolated yields and high selectivity (38 examples).

18.
Org Lett ; 22(11): 4213-4216, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32396006

RESUMO

A pressure-based variable-bed flow reactor built for peptide synthesis and capable of real-time monitoring of resin swelling was adapted for automated glycan assembly. In the context of the solid-phase synthesis of several oligosaccharides, the coupling efficiencies, resin growth patterns, and saccharide solvation during the synthesis were determined. The presented work provides the first estimation of on-resin oligosaccharide solvation and an alternative technique to UV-vis monitoring.


Assuntos
Polissacarídeos/química , Polissacarídeos/síntese química , Resinas Vegetais/química , Configuração de Carboidratos
19.
Front Physiol ; 10: 1424, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824336

RESUMO

BACKGROUND: The pre-exhaustion (PreEx) method is used as a resistance training (RT) method to increase muscle mass, yet the chronic effects of this method are poorly understood. OBJECTIVE: Although readily prescribed as a RT method for promotion of muscle hypertrophy, few researches give light to gains made after chronic PreEx RT. Therefore, we compared the effects of traditional versus PreEx RT programs on muscle strength, body composition, and muscular hypertrophy in adult males. METHODS: Untrained subjects (age: 31.37 ± 6.83 years; height: 175.29 ± 5.52 cm; body mass: 82.04 ± 13.61 kg; 1RM leg press: 339.86 ± 61.17 kg; 1RM leg extension: 121.71 ± 11.93 kg) were submitted to 9 weeks of RT with weekly sessions. Traditional (TRT) group (n = 12) performed three sets at 45° of leg press exercise at 75% of 1RM, PreEx group (n = 12) completed a set to failure on a leg extension machine prior to the leg press, and the control (CON) group (n = 7) did not train. Maximum strength, muscle thickness, and body composition were analyzed. RESULTS: PreEx group increased in maximal strength on leg press (16 ± 8%) and leg extension (17 ± 11%), while the TRT group improved by 15 ± 9 and 11 ± 4%, respectively. The thickness of the quadriceps muscles increased for both intervention groups. Specifically, the post-training thickness of the vastus lateralis was significantly higher for PreEx (55%) compared to the CON group. The TRT group presented a greater loss of total and thigh fat mass when compared with the PreEx method. These results were found in the presence of a lower training load for the PreEx group. CONCLUSION: The PreEx training can decrease the total training volume while maintaining results in strength and hypertrophy when comparing to TRT. However, TRT may be optimal if the goal is to decrease fat mass.

20.
Chem Commun (Camb) ; 55(97): 14598-14601, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31742308

RESUMO

On-resin aggregation and incomplete amide bond formation are major challenges for solid-phase peptide synthesis that are difficult to be monitored in real-time. Incorporation of a pressure-based variable bed flow reactor into an automated solid-phase peptide synthesizer permitted real-time monitoring of resin swelling to determine amino acid coupling efficiency and on-resin aggregation.

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