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1.
Sports Med ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38722535

RESUMEN

BACKGROUND: Wheelchair tennis, a globally popular sport, features a professional tour spanning 40 countries and over 160 tournaments. Despite its widespread appeal, information about the physical demands of wheelchair tennis is scattered across various studies, necessitating a comprehensive systematic review to synthesise available data. OBJECTIVE: The aim was to provide a detailed synthesis of the physical demands associated with wheelchair tennis, encompassing diverse factors such as court surfaces, performance levels, sport classes, and sexes. METHODS: We conducted comprehensive searches in the PubMed, Embase, CINAHL, and SPORTDiscus databases, covering articles from inception to March 1, 2023. Forward and backward citation tracking from the included articles was carried out using Scopus, and we established eligibility criteria following the Population, Exposure, Comparison, Outcome, and Study design (PECOS) framework. Our study focused on wheelchair tennis players participating at regional, national, or international levels, including both juniors and adults, and open and quad players. We analysed singles and doubles matches and considered sex (male, female), sport class (open, quad), and court surface type (hard, clay, grass) as key comparative points. The outcomes of interest encompassed play duration, on-court movement, stroke performance, and physiological match variables. The selected study designs included observational cross-sectional, longitudinal, and intervention studies (baseline data only). We calculated pooled means or mean differences with 95% confidence intervals (CIs) and employed a random-effects meta-analysis with robust variance estimation. We assessed heterogeneity using Cochrane Q and 95% prediction intervals. RESULTS: Our literature search retrieved 643 records, with 24 articles meeting our inclusion criteria. Most available information focused on international male wheelchair tennis players in the open division, primarily competing in singles on hard courts. Key findings (mean [95% CI]) for these players on hard courts were match duration 65.9 min [55.0-78.8], set duration 35.0 min [28.2-43.5], game duration 4.6 min [0.92-23.3], rally duration 6.1 s [3.7-10.2], effective playing time 19.8% [18.9-20.7], and work-to-rest ratio 1:4.1 [1:3.7-1:4.4]. Insufficient data were available to analyse play duration for female players. However, for the available data on hard court matches, the average set duration was 34.8 min [32.5-37.2]. International male players on hard court covered an average distance per match of 3859 m [1917-7768], with mean and peak average forward speeds of 1.06 m/s [0.85-1.32] and 3.55 m/s [2.92-4.31], respectively. These players executed an average of 365.9 [317.2-422.1] strokes per match, 200.6 [134.7-299.0] per set, 25.4 [16.7-38.7] per game, and 3.4 [2.6-4.6] per rally. Insufficient data were available for a meta-analysis of female players' on-court movement and stroke performance. The average and peak heart rates of international male players on hard court were 134.3 [124.2-145.1] and 166.0 [132.7-207.6] beats per minute, and the average match heart rate expressed as a percentage of peak heart rate was 74.7% [46.4-100]. We found no studies concerning regional players or juniors, and only one study on doubles match play. CONCLUSIONS: While we present a comprehensive overview of the physical demands of wheelchair tennis, our understanding predominantly centres around international male players competing on hard courts in the open division. To attain a more comprehensive insight into the sport's physical requirements, future research should prioritise the inclusion of data on female and quad players, juniors, doubles, and matches played on clay and grass court surfaces. Such endeavours will facilitate the development of more tailored and effective training programmes for wheelchair tennis players and coaches. The protocol for this systematic review was registered a priori at the International Platform of Registered Systematic Review and Meta-analysis Protocols (Registration https://doi.org/10.37766/inplasy2023.3.0060 ).

2.
ACS Chem Neurosci ; 15(2): 315-327, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38189238

RESUMEN

Primary metabolites of mushroom tryptamines, psilocybin and baeocystin (i.e., psilocin and norpsilocin), exhibit potent agonist activity at the serotonin 2A receptor (5-HT2A) in vitro but differ in their 5-HT2A-mediated effects in vivo. In particular, psilocin produces centrally mediated psychedelic effects in vivo, whereas norpsilocin, differing only by the loss of an N-methyl group, is devoid of psychedelic-like effects. These observations suggest that the secondary methylamine group in norpsilocin impacts its central nervous system (CNS) bioavailability but not its receptor pharmacodynamics. To test this hypothesis, eight norpsilocin derivatives were synthesized with varied secondary alkyl-, allyl-, and benzylamine groups, primarily aiming to increase their lipophilicity and brain permeability. Structure-activity relationships for the norpsilocin analogues were evaluated using the mouse head-twitch response (HTR) as a proxy for CNS-mediated psychedelic-like effects. HTR studies revealed that extending the N-methyl group of norpsilocin by a single methyl group, to give the corresponding secondary N-ethyl analogue (4-HO-NET), was sufficient to produce psilocin-like activity (median effective dose or ED50 = 1.4 mg/kg). Notably, N-allyl, N-propyl, N-isopropyl, and N-benzyl derivatives also induced psilocin-like HTR activity (ED50 = 1.1-3.2 mg/kg), with variable maximum effects (26-77 total HTR events). By contrast, adding bulkier tert-butyl or cyclohexyl groups in the same position did not elicit psilocin-like HTRs. Pharmacological assessments of the tryptamine series in vitro demonstrated interactions with multiple serotonin receptor subtypes, including 5-HT2A, and other CNS signaling proteins (e.g., sigma receptors). Overall, our data highlight key structural requirements for CNS-mediated psychedelic-like effects of norpsilocin analogues.


Asunto(s)
Alucinógenos , Ratones , Animales , Alucinógenos/química , Serotonina/metabolismo , Receptores de Serotonina/metabolismo , Encéfalo/metabolismo , Receptor de Serotonina 5-HT2A/metabolismo
3.
Molecules ; 28(12)2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37375403

RESUMEN

Kappa opioid receptor (KOR) agonists have preclinical antipsychostimulant effects; however, adverse side effects have limited their therapeutic development. In this preclinical study, conducted in Sprague Dawley rats, B6-SJL mice, and non-human primates (NHPs), we evaluated the G-protein-biased analogue of salvinorin A (SalA), 16-bromo salvinorin A (16-BrSalA), for its anticocaine effects, side effects, and activation of cellular signaling pathways. 16-BrSalA dose-dependently decreased the cocaine-primed reinstatement of drug-seeking behavior in a KOR-dependent manner. It also decreased cocaine-induced hyperactivity, but had no effect on responding for cocaine on a progressive ratio schedule. Compared to SalA, 16-BrSalA had an improved side effect profile, with no significant effects in the elevated plus maze, light-dark test, forced swim test, sucrose self-administration, or novel object recognition; however, it did exhibit conditioned aversive effects. 16-BrSalA increased dopamine transporter (DAT) activity in HEK-293 cells coexpressing DAT and KOR, as well as in rat nucleus accumbens and dorsal striatal tissue. 16-BrSalA also increased the early phase activation of extracellular-signal-regulated kinases 1 and 2, as well as p38 in a KOR-dependent manner. In NHPs, 16-BrSalA caused dose-dependent increases in the neuroendocrine biomarker prolactin, similar to other KOR agonists, at doses without robust sedative effects. These findings highlight that G-protein-biased structural analogues of SalA can have improved pharmacokinetic profiles and fewer side effects while maintaining their anticocaine effects.


Asunto(s)
Cocaína , Ratones , Ratas , Humanos , Animales , Cocaína/farmacología , Receptores Opioides kappa/metabolismo , Ratas Sprague-Dawley , Células HEK293 , Ansiedad/tratamiento farmacológico , Recompensa , Locomoción
4.
ACS Omega ; 8(24): 22132-22137, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37360440

RESUMEN

A divergent two-step process has provided access to optically pure enantiomers of MDMA and MDA, clinically relevant phenylisopropylamine entactogens. Target compounds were synthesized from commercially available alanine-derived aziridines. Critical process parameters were identified, and the reactions were optimized to avoid chromatographic purifications toward gram-scale isolations, providing (R)-(-)-MDMA, (S)-(+)-MDMA, (R)-(-)-MDA, and (S)-(+)-MDA each in greater than 98% purity by UPLC, >99% enantiomeric excess, and net yields between 50 and 60% for the complete process.

5.
Sports Med ; 53(4): 807-836, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36752978

RESUMEN

BACKGROUND: Tennis is a multidirectional high-intensity intermittent sport for male and female individuals played across multiple surfaces. Although several studies have attempted to characterise the physical demands of tennis, a meta-analysis is still lacking. OBJECTIVE: We aimed to describe and synthesise the physical demands of tennis across the different court surfaces, performance levels and sexes. METHODS: PubMed, Embase, CINAHL and SPORTDiscus were searched from inception to 19 April, 2022. A backward citation search was conducted for included articles using Scopus. The PECOS framework was used to formulate eligibility criteria. POPULATION: tennis players of regional, national or international playing levels (juniors and adults). EXPOSURE: singles match play. Comparison: sex (male/female), court surface (hard, clay, grass). OUTCOME: duration of play, on-court movement and stroke performance. STUDY DESIGN: cross-sectional, longitudinal. Pooled means or mean differences with 95% confidence intervals were calculated. A random-effects meta-analysis with robust variance estimation was performed. The measures of heterogeneity were Cochrane Q and 95% prediction intervals. Subgroup analysis was used for different court surfaces. RESULTS: The literature search generated 7736 references; 64 articles were included for qualitative and 42 for quantitative review. Mean [95% confidence interval] rally duration, strokes per rally and effective playing time on all surfaces were 5.5 s [4.9, 6.3], 4.1 [3.4, 5.0] and 18.6% [15.8, 21.7] for international male players and 6.4 s [5.4, 7.6], 3.9 [2.4, 6.2] and 20% [17.3, 23.3] for international female players. Mean running distances per point, set and match were 9.6 m [7.6, 12.2], 607 m [443, 832] and 2292 m [1767, 2973] (best-of-5) for international male players and 8.2 m [4.4, 15.2], 574 m [373, 883] and 1249 m [767, 2035] for international female players. Mean first- and second-serve speeds were 182 km·h-1 [178, 187] and 149 km·h-1 [135, 164] for international male players and 156 km·h-1 95% confidence interval [151, 161] and 134 km·h-1 [107, 168] for international female players. CONCLUSIONS: The findings from this study provide a comprehensive summary of the physical demands of tennis. These results may guide tennis-specific training programmes. We recommend more consistent measuring and reporting of data to enable future meta-analysts to pool meaningful data. CLINICAL TRIAL REGISTRATION: The protocol for this systematic review was registered a priori at the Open Science Framework (Registration DOI https://doi.org/10.17605/OSF.IO/MDWFY ).


Asunto(s)
Tenis , Adulto , Humanos , Masculino , Femenino , Estudios Transversales , Conducta Competitiva
6.
Sports Med Health Sci ; 4(1): 70-73, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35782775

RESUMEN

Altered biomechanics due to amputation can contribute to substantial limitations, influencing sporting activities. Individuals with lower extremity amputations or congenital lower limb deficiency are encouraged to participate in para-sports. However, to compete in Paralympic sports, the candidate must have an impairment that results in lower extremity loss of function and meets or exceeds the sport's minimum impairment criteria (MIC). This review will focus on the MIC for competitive wheelchair tennis. Limb deficiency is known as one of the MIC used to regulate participation in competitive para-sports since it impacts gait, kinematics, and biomechanics of both the upper and lower body. Notwithstanding, it is questionable whether the MIC concerning limb deficiency is set at the correct level for determining eligibility for participating in Paralympic sports. This study aims to provide an overview of the evidence examining the impact of different partial foot amputation (PFA) levels on gait as a proxy for sporting performance. This scoping review will be based on a 6-step methodological framework and Preferred Reporting Items for Systematic Reviews and Meta-Analysis, extension for scoping reviews (PRISMA-ScR). Studies will be selected from PubMed, Embase, CINAHL, and SPORTDiscus. Two authors will screen the titles/abstracts independently. Selected studies will be scrutinised, and the same authors will extract data. Findings will be relevant to informing the evidence-based development of MIC for lower limb impairment after PFA and may be extrapolated to specific Paralympic sports, including wheelchair tennis. Results will be disseminated through scientific publications and conferences to audiences interested in Paralympic sports.

7.
Br J Sports Med ; 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36588404

RESUMEN

OBJECTIVE: This scoping review examines how different levels and types of partial foot amputation affect gait and explores how these findings may affect the minimal impairment criteria for wheelchair tennis. METHODS: Four databases (PubMed, Embase, CINAHL and SPORTDiscus) were systematically searched in February 2021 for terms related to partial foot amputation and ambulation. The search was updated in February 2022. All study designs investigating gait-related outcomes in individuals with partial foot amputation were included and independently screened by two reviewers based on Arksey and O'Malley's methodological framework and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews. RESULTS: Twenty-nine publications with data from 252 participants with partial foot amputation in 25 studies were analysed. Toe amputations were associated with minor gait abnormalities, and great toe amputations caused loss of push-off in a forward and lateral direction. Metatarsophalangeal amputations were associated with loss of stability and decreased gait speed. Ray amputations were associated with decreased gait speed and reduced lower extremity range of motion. Transmetatarsal amputations and more proximal amputations were associated with abnormal gait, substantial loss of power generation across the ankle and impaired mobility. CONCLUSIONS: Partial foot amputation was associated with various gait changes, depending on the type of amputation. Different levels and types of foot amputation are likely to affect tennis performance. We recommend including first ray, transmetatarsal, Chopart and Lisfranc amputations in the minimum impairment criteria, excluding toe amputations (digits two to five), and we are unsure whether to include or exclude great toe, ray (two to five) and metatarsophalangeal amputations. TRIAL REGISTRATION: The protocol of this scoping review was previously registered at the Open Science Framework Registry (https://osf.io/8gh9y) and published.

8.
Sports Med Health Sci ; 4(4): 225-238, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36600967

RESUMEN

Accurate and reliable evaluation of muscle strength in para-athletes is essential for monitoring the effectiveness of strength training and/or rehabilitation programmes, and sport classification. Our aim is to synthesise evidence related to assessing muscle strength in para-athletes. Four databases were searched from January 1990 to July 2021 for observational studies focusing on strength assessment. Independent screening, data extraction, and quality assessment were performed in duplicate. A total of 1764 potential studies were identified. Thirty met the inclusion criteria and were included in the review. The mean age of participants was 30.7 years (standard deviation [SD]: 2.4). The majority were men (88%) participating in wheelchair sports, including basketball, rugby, and tennis (23/30: 76%). Overall quality varied, with more than half of the studies failing to identify strategies for dealing with confounding variables. Despite manual muscle testing being a standard component of para-sport classification systems, evidence examining strength characteristics in para-athletes is derived primarily from isometric and isokinetic testing. In studies that included comparative strength data, findings were mixed. Some studies found strength values were similar to or lower than able-bodied athletic controls. However, an important observation was that others reported higher shoulder strength in para-athletes taking part in wheelchair sports than both able-bodied and disabled non-athletes. Studies need to develop accessible, standardised strength testing methods that account for training influence and establish normative strength values in para-athletes. There is also a need for additional studies that include female para-athletes and para-athletes with greater functional impairments.

9.
Phys Ther Sport ; 50: 15-21, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33857813

RESUMEN

OBJECTIVE: To investigate the test-retest reliability and validity of the Kerlan-Jobe Orthopaedic Clinic shoulder and elbow score (KJOC) in elite Canoe Slalom athletes and determine its ability to predict future shoulder pain. DESIGN: Observational study with embedded test-retest reliability study. SETTING: British Canoe Slalom National Training Centre. PARTICIPANTS: Nineteen athletes from the British Canoe Slalom team for the 2019 season. MAIN OUTCOME MEASURES: The KJOC was completed at the start of winter training and start of the 2019 competitive season. Current, historical (6-months pre-questionnaire) and prospective (4-months post-questionnaire) shoulder injuries were recorded. RESULTS: Test-retest reliability was found to be excellent (ICC3,1 = 0.97), with a minimal detectable change (MDC95%) of 6.7. Compared to uninjured athletes, currently injured and historically injured athletes scored significantly lower (p = 0.002 and p = 0.011, respectively), with the difference between means > MDC95%. A cut-off of 88 was found to be predictive of shoulder pain (AUC: 0.779; sensitivity: 0.60; specificity: 0.95; positive likelihood ratio: 11.4). CONCLUSION: The KJOC demonstrated excellent reliability and can distinguish between athletes with and without current or historical shoulder pain. A KJOC score of <88 was associated with increased risk of shoulder pain. The KJOC should be completed as part of a risk profile for shoulder pain.


Asunto(s)
Lesiones de Codo , Lesiones del Hombro/diagnóstico , Dolor de Hombro/diagnóstico , Deportes Acuáticos/lesiones , Adulto , Atletas , Traumatismos en Atletas/diagnóstico , Codo , Femenino , Humanos , Masculino , Ortopedia , Medición de Resultados Informados por el Paciente , Estudios Prospectivos , Reproducibilidad de los Resultados , Factores de Riesgo , Hombro , Encuestas y Cuestionarios , Adulto Joven
10.
Phys Ther Sport ; 46: 220-225, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32987357

RESUMEN

OBJECTIVE: To investigate the correlation of arm length with different CKCUEST measures and determine if a modification of the test position (modified-CKCUEST), or normalisation of the CKCUEST (normalised-CKCUEST) score after testing, control for arm length most effectively. STUDY DESIGN: Quasi Experimental. SETTING: British Canoe Slalom National Training Centre. PARTICIPANTS: Thirteen (5 male, 8 female) asymptomatic national squad canoe/kayak slalom athletes were recruited during winter profiling. MAIN OUTCOME MEASURE: Three measures of the CKCUEST were investigated. The CKCUEST, hands 36 inches apart; modified-CKCUEST, hands arm width apart (measured as C7 spinous process to tip of middle finger); and normalised-CKCUEST (measured as CKCUEST score/arm length). RESULTS: A significant positive correlation was found between arm length and the CKCUEST score (r = 0.807; p = 0.001) and normalised-CKCUEST score (r = 0.654; p = 0.015). No significant correlation was found between the modified-CKCUEST score and arm length (p = 0.745). A statistically significant difference between narrow and wide hand positions, greater than the minimal detectable change, was found (p = 0.000). CONCLUSIONS: Arm length has a significant impact on CKCUEST score. The modified-CKCUEST score corrected for arm length where the normalised-CKCUEST score did not. Modifying the CKCUEST to individual anthropometrics needs to be performed pre-testing when comparisons are being made between individuals or groups.


Asunto(s)
Brazo/anatomía & histología , Prueba de Esfuerzo/métodos , Extremidad Superior/fisiología , Deportes Acuáticos/fisiología , Femenino , Humanos , Masculino , Valores de Referencia , Factores Sexuales , Adulto Joven
11.
J Org Chem ; 83(2): 980-992, 2018 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-29271194

RESUMEN

A reliable protocol to synthesize both racemic and chiral (E)-4-iodobut-3-en-1-ols from aldehydes or epoxides, respectively, containing various aromatic and aliphatic substitutions has been established. The utility of these compounds was then demonstrated by providing access to known fungal decanolides as well as novel aromatic macrocycles. The protocol provided a gram-scale route to (-)-aspinolide A and (-)-5-epi-aspinolide A utilizing a catalytic Nozaki-Hiyama-Kishi reaction to close the macrolide in the final step in 65-84% yields.


Asunto(s)
Butanoles/síntesis química , Lactonas/síntesis química , Compuestos Macrocíclicos/síntesis química , Aldehídos/química , Butanoles/química , Compuestos Epoxi/química , Lactonas/química , Compuestos Macrocíclicos/química , Estructura Molecular , Estereoisomerismo
12.
Org Lett ; 19(19): 5414-5417, 2017 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-28910112

RESUMEN

Informed by previous semisynthetic work on salvinorin A, a modular total synthesis has been developed capable of producing novel compounds targeting the κ-opioid receptor. The strategy has permitted the deliberate simplification and introduction of functionality about the target molecule to provide access to molecular features on salvinorin A otherwise unattainable by semisynthesis. Using this approach, a potent pseudo-neoclerodane κ-opioid receptor ligand (2) has been realized.


Asunto(s)
Diterpenos/química , Diterpenos de Tipo Clerodano , Ligandos , Estructura Molecular , Receptores Opioides kappa
13.
Chem Commun (Camb) ; 50(89): 13668-71, 2014 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-25096018

RESUMEN

Plasma homocysteine (Hcy) is an important risk factor for various diseases. A novel redox-sensitive fluorescent probe is developed for the selective detection of Hcy. A linear calibration curve has been obtained in buffer and plasma for the quantitative determination of Hcy in such media.


Asunto(s)
Homocisteína/sangre , Aminoácidos/química , Animales , Azidas/síntesis química , Azidas/química , Bovinos , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Homocisteína/análisis , Homocisteína/química , Oxidación-Reducción , Fosfatos/química , Suero/química , Espectrometría de Fluorescencia
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