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1.
Sports Med Open ; 10(1): 29, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561438

RESUMEN

BACKGROUND: Change of direction (COD) movements are associated with non-contact anterior cruciate ligament (ACL) injuries in multidirectional sports. Females appear at increased risk compared to males, which could be attributable to whole body kinematic strategies and greater multiplanar knee joint loads (KJLs) during COD which can increase ACL loading. OBJECTIVE: The aim of this systematic review and meta-analysis was to examine and quantitatively synthesise the evidence for differences between males and females regarding KJLs and their biomechanical determinants (whole body kinematic strategies determining KJLs) during COD tasks. METHODS: Databases including SPORTDiscus, Web of Science, and PubMed were systematically searched (July 2021-June 2023) for studies that compared differences in knee joint loads and biomechanical determinants of KJLs during COD between males and females. Inclusion criteria were: (1) females and males with no prior history of ACL injury (18-40 years); (2) examined biomechanical determinants of KJLs and/ or KJLs during COD tasks > 20°; (3) compared ≥ 1 outcome measure between males and females. Studies published between 2000 and 2023 examining a cutting task > 20° with a preceding approach run that compared KJLs or the whole body multiplanar kinematics associated with them, between sexes, using three-dimensional motion analysis. RESULTS: This meta-analysis included 17 studies with a pooled sample size of 451 participants (227 males, 224 females). Meta-analysis revealed females displayed significantly less peak knee flexion during stance (SMD: 0.374, 95% CI 0.098-0.649, p = 0.008, I2: 0%); greater knee abduction at initial contact (IC) (SMD: 0.687, 95% CI 0.299-1.076, p = 0.001, I2: 55%); less hip internal rotation (SMD: 0.437, 95% CI 0.134-0.741, p = 0.005, I2: 34%) and hip abduction at IC (SMD: -0.454, 95% CI 0.151-0.758, p = 0.003, I2: 33%). No significant differences were observed between males and females for any internal or externally applied KJLs. All retrieved studies failed to control for strength, resistance training or skill history status. CONCLUSION: No differences were observed in KJLs between males and females despite females displaying greater knee abduction at IC and less peak knee flexion during the stance phase of CODs, which are visual characteristics of non-contact ACL injury. Further research is required to examine if this translates to a similar injury risk, considering morphological differences in strain characteristics of the ACL between males and females. This observation may in part explain the disproportionate ACL injury incidence in female multidirectional athletes. Further higher quality controlled research is required whereby participants are matched by skill training history, resistance training history and strength status to ensure an appropriate comparison between males and females.

2.
J Hum Kinet ; 90: 5-15, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38380295

RESUMEN

Over the past two decades the importance of trunk contribution to sporting performance has been highlighted through the expanse of literature concerning core stability and strength. However, the role of trunk motion and the abdominal muscles are yet to be established during sprint kayak performance. The purpose of this study was to determine the associations among trunk rotation, kayak velocity, and abdominal muscle activity during on-water sprint kayaking. Eight international paddlers completed five 150 m sprint trials. During each trial peak muscle activation (peak root-mean-squared electromyogram) of the latissimus dorsi, rectus abdominus, external obliques and rectus femoris for ipsilateral (stroke side) and contralateral (opposite side) were recorded as the paddler passed through a 5-m calibrated volume, in conjunction with upper and lower trunk rotation and kayak velocity. Results indicated a significant strong negative relationship between lower trunk rotation and peak velocity (r = -0.684, p < 0.05). Furthermore, a significant strong positive relationship (p < 0.05) with mean velocity was identified for the contralateral rectus abdominus and multiple significant associations between the rectus femoris, rectus abdominus and external obliques during the paddle stroke. Findings indicate that limiting the rotation of the lower trunk will increase both the peak and the mean velocity, with the rectus abdominus, external oblique and rectus femoris combining to assist in this process. Training should therefore focus on developing the strength of these muscle groups to enhance performance.

3.
PLoS One ; 18(5): e0286259, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37252922

RESUMEN

BACKGROUND: Schools are high-risk settings for infectious disease transmission. Wastewater monitoring for infectious diseases has been used to identify and mitigate outbreaks in many near-source settings during the COVID-19 pandemic, including universities and hospitals but less is known about the technology when applied for school health protection. This study aimed to implement a wastewater surveillance system to detect SARS-CoV-2 and other public health markers from wastewater in schools in England. METHODS: A total of 855 wastewater samples were collected from 16 schools (10 primary, 5 secondary and 1 post-16 and further education) over 10 months of school term time. Wastewater was analysed for SARS-CoV-2 genomic copies of N1 and E genes by RT-qPCR. A subset of wastewater samples was sent for genomic sequencing, enabling determination of the presence of SARS-CoV-2 and emergence of variant(s) contributing to COVID-19 infections within schools. In total, >280 microbial pathogens and >1200 AMR genes were screened using RT-qPCR and metagenomics to consider the utility of these additional targets to further inform on health threats within the schools. RESULTS: We report on wastewater-based surveillance for COVID-19 within English primary, secondary and further education schools over a full academic year (October 2020 to July 2021). The highest positivity rate (80.4%) was observed in the week commencing 30th November 2020 during the emergence of the Alpha variant, indicating most schools contained people who were shedding the virus. There was high SARS-CoV-2 amplicon concentration (up to 9.2x106 GC/L) detected over the summer term (8th June - 6th July 2021) during Delta variant prevalence. The summer increase of SARS-CoV-2 in school wastewater was reflected in age-specific clinical COVID-19 cases. Alpha variant and Delta variant were identified in the wastewater by sequencing of samples collected from December to March and June to July, respectively. Lead/lag analysis between SARS-CoV-2 concentrations in school and WWTP data sets show a maximum correlation between the two-time series when school data are lagged by two weeks. Furthermore, wastewater sample enrichment coupled with metagenomic sequencing and rapid informatics enabled the detection of other clinically relevant viral and bacterial pathogens and AMR. CONCLUSIONS: Passive wastewater monitoring surveillance in schools can identify cases of COVID-19. Samples can be sequenced to monitor for emerging and current variants of concern at the resolution of school catchments. Wastewater based monitoring for SARS-CoV-2 is a useful tool for SARS-CoV-2 passive surveillance and could be applied for case identification and containment, and mitigation in schools and other congregate settings with high risks of transmission. Wastewater monitoring enables public health authorities to develop targeted prevention and education programmes for hygiene measures within undertested communities across a broad range of use cases.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2/genética , Aguas Residuales , Salud Pública , Pandemias , Monitoreo Epidemiológico Basado en Aguas Residuales , Inglaterra/epidemiología , ARN Viral
4.
Microb Genom ; 9(4)2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37074153

RESUMEN

Wastewater-based epidemiology has been used extensively throughout the COVID-19 (coronavirus disease 19) pandemic to detect and monitor the spread and prevalence of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) and its variants. It has proven an excellent, complementary tool to clinical sequencing, supporting the insights gained and helping to make informed public-health decisions. Consequently, many groups globally have developed bioinformatics pipelines to analyse sequencing data from wastewater. Accurate calling of mutations is critical in this process and in the assignment of circulating variants; yet, to date, the performance of variant-calling algorithms in wastewater samples has not been investigated. To address this, we compared the performance of six variant callers (VarScan, iVar, GATK, FreeBayes, LoFreq and BCFtools), used widely in bioinformatics pipelines, on 19 synthetic samples with known ratios of three different SARS-CoV-2 variants of concern (VOCs) (Alpha, Beta and Delta), as well as 13 wastewater samples collected in London between the 15th and 18th December 2021. We used the fundamental parameters of recall (sensitivity) and precision (specificity) to confirm the presence of mutational profiles defining specific variants across the six variant callers. Our results show that BCFtools, FreeBayes and VarScan found the expected variants with higher precision and recall than GATK or iVar, although the latter identified more expected defining mutations than other callers. LoFreq gave the least reliable results due to the high number of false-positive mutations detected, resulting in lower precision. Similar results were obtained for both the synthetic and wastewater samples.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiología , Monitoreo Epidemiológico Basado en Aguas Residuales , Aguas Residuales , Algoritmos
5.
Microbiol Spectr ; 11(1): e0317722, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36629447

RESUMEN

Within months of the COVID-19 pandemic being declared on March 20, 2020, novel, more infectious variants of SARS-CoV-2 began to be detected in geospatially distinct regions of the world. With international travel being a lead cause of spread of the disease, the importance of rapidly identifying variants entering a country is critical. In this study, we utilized wastewater-based epidemiology (WBE) to monitor the presence of variants in wastewater generated in managed COVID-19 quarantine facilities for international air passengers entering the United Kingdom. Specifically, we developed multiplex reverse transcription quantitative PCR (RT-qPCR) assays for the identification of defining mutations associated with Beta (K417N), Gamma (K417T), Delta (156/157DEL), and Kappa (E154K) variants which were globally prevalent at the time of sampling (April to July 2021). The assays sporadically detected mutations associated with the Beta, Gamma, and Kappa variants in 0.7%, 2.3%, and 0.4% of all samples, respectively. The Delta variant was identified in 13.3% of samples, with peak detection rates and concentrations observed in May 2021 (24%), concurrent with its emergence in the United Kingdom. The RT-qPCR results correlated well with those from sequencing, suggesting that PCR-based detection is a good predictor for variant presence; although, inadequate probe binding may lead to false positive or negative results. Our findings suggest that WBE coupled with RT-qPCR may be used as a rapid, initial assessment to identify emerging variants at international borders and mass quarantining facilities. IMPORTANCE With the global spread of COVID-19, it is essential to identify emerging variants which may be more harmful or able to escape vaccines rapidly. To date, the gold standard to assess variants circulating in communities has been the sequencing of the S gene or the whole genome of SARS-CoV-2; however, that approach is time-consuming and expensive. In this study, we developed two duplex RT-qPCR assays to detect and quantify defining mutations associated with the Beta, Gamma, Delta, and Kappa variants. The assays were validated using RNA extracts derived from wastewater samples taken at quarantine facilities. The results showed good correlation with the results of sequencing and demonstrated the emergence of the Delta variant in the United Kingdom in May 2021. The assays developed here enable the assessment of variant-specific mutations within 2 h after the RNA extract was generated which is essential for outbreak rapid response.


Asunto(s)
COVID-19 , SARS-CoV-2 , Aguas Residuales , Humanos , COVID-19/diagnóstico , COVID-19/epidemiología , Prueba de COVID-19 , Mutación , Pandemias , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , ARN , SARS-CoV-2/genética , Aguas Residuales/virología
6.
Gait Posture ; 98: 343-354, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36306544

RESUMEN

BACKGROUND: Robotic exoskeletons have been developed to assist locomotion and address gait abnormalities in children with cerebral palsy (CP). These wearable assistive devices provide powered assistance to the lower-extremity joints, as well as support and stability. RESEARCH QUESTION: Does exoskeleton-assisted walking improve gait in children with CP? METHODS: The PRISMA guidelines were used to conduct this systematic review. Articles were obtained in a search of the following electronic databases: Embase, CINAHL Complete, PubMed, Web of Science and MEDLINE. Studies investigating spatiotemporal, kinematic, kinetic, muscle activity and/or physiological parameters during exoskeleton-assisted walking in children with CP were included. All articles were assessed for methodological quality using an adapted version of the Quality Assessment Tool for Before-After (Pre-Post) Studies with No Control Group, provided by the National Institutes of Health (NIH). RESULTS: Thirteen studies were included. They involved the use of the following exoskeletons: tethered knee exoskeleton, pediatric knee exoskeleton (P.REX), untethered ankle exoskeleton, WAKE-Up ankle module, WAKE-Up ankle & knee module and unilateral ankle exosuit. Methodological quality varied, with key limitations in sample size and allocated time to adapt to the exoskeleton. There was a consensus that robotic exoskeletons improve gait given careful optimisation of exoskeleton torque and sufficient exoskeleton practice time for each participant. Improvements in gait included reduced metabolic cost of walking, increased walking speed, and increased knee and hip extension during stance. Furthermore, exoskeletons with an actuated ankle module were shown to promote normal ankle rocker function. SIGNIFICANCE: Robotic exoskeletons have the potential to improve the mobility of CP children and may therefore increase community participation and improve quality of life. Future work should involve larger controlled intervention studies utilising robotic exoskeletons to improve gait in children with CP. These studies should ensure sufficient exoskeleton practice time for each participant.


Asunto(s)
Parálisis Cerebral , Dispositivo Exoesqueleto , Humanos , Niño , Parálisis Cerebral/complicaciones , Calidad de Vida , Marcha/fisiología , Caminata/fisiología , Fenómenos Biomecánicos
7.
Appl Ergon ; 101: 103717, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35202961

RESUMEN

The aim of this study was to examine the impact of backpack load carriage on lower limb strength and loading rate change in a cohort that match military recruit profiles. Twenty-six participants walked on a treadmill either carrying a military load carriage system (32 kg) or unloaded for 2 h on two consecutive days. Participants ground reaction forces and strength measures were assessed using a force platform and dynamometry, respectively. Testing included assessments before and after treadmill walking on days one and two, and 24 h following day 2. When assessed by mixed methods ANOVA (alpha: 0.05) statistically significant interaction effects were observed for loading peak (p = 0.031), loading rate (p = 0.035) and plantarflexor torque dynamometry variables at 60°s-1 (p = 0.011) and 120°s-1 (p = 0.024). Repeated measures correlation highlighted associations between plantarflexor torque at 60°s-1 and loading rate (r = -0.901, p < 0.001). Load carriage reduced lower limb torque which did not recover between days. Plantarflexor torque reductions were associated with increases in loading rate. Practitioners should consider that load bearers are more likely to experience lower limb injury during multi-day load carriage. Future work should develop protocols to reduce plantarflexor torque loss in order to reduce ground reaction force change.


Asunto(s)
Tobillo , Caminata , Fenómenos Biomecánicos , Humanos , Extremidad Inferior , Torque , Soporte de Peso
8.
Sci Total Environ ; 808: 151916, 2022 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-34826466

RESUMEN

Wastewater-based epidemiology (WBE) has become a complimentary surveillance tool during the SARS-CoV-2 pandemic. Viral concentration methods from wastewater are still being optimised and compared, whilst viral recovery under different wastewater characteristics and storage temperatures remains poorly understood. Using urban wastewater samples, we tested three viral concentration methods; polyethylene glycol precipitation (PEG), ammonium sulphate precipitation (AS), and CP select™ InnovaPrep® (IP) ultrafiltration. We found no major difference in SARS-CoV-2 and faecal indicator virus (crAssphage) recovery from wastewater samples (n = 46) using these methods, PEG slightly (albeit non-significantly), outperformed AS and IP for SARS-CoV-2 detection, as a higher genome copies per litre (gc/l) was recorded for a larger proportion of samples. Next generation sequencing of 8 paired samples revealed non-significant differences in the quality of data between AS and IP, though IP data quality was slightly better and less variable. A controlled experiment assessed the impact of wastewater suspended solids (turbidity; 0-400 NTU), surfactant load (0-200 mg/l), and storage temperature (5-20 °C) on viral recovery using the AS and IP methods. SARS-CoV-2 recoveries were >20% with AS and <10% with IP in turbid samples, whilst viral recoveries for samples with additional surfactant were between 0-18% for AS and 0-5% for IP. Turbidity and sample storage temperature combined had no significant effect on SARS-CoV-2 recovery (p > 0.05), whilst surfactant and storage temperature combined were significant negative correlates (p < 0.001 and p < 0.05, respectively). In conclusion, our results show that choice of methodology had small effect on viral recovery of SARS-CoV-2 and crAssphage in wastewater samples within this study. In contrast, sample turbidity, storage temperature, and surfactant load did affect viral recovery, highlighting the need for careful consideration of the viral concentration methodology used when working with wastewater samples.


Asunto(s)
COVID-19 , Aguas Residuales , Humanos , SARS-CoV-2 , Tensoactivos , Temperatura
9.
J Hazard Mater ; 424(Pt B): 127456, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34655869

RESUMEN

The COVID-19 pandemic has put unprecedented pressure on public health resources around the world. From adversity, opportunities have arisen to measure the state and dynamics of human disease at a scale not seen before. In the United Kingdom, the evidence that wastewater could be used to monitor the SARS-CoV-2 virus prompted the development of National wastewater surveillance programmes. The scale and pace of this work has proven to be unique in monitoring of virus dynamics at a national level, demonstrating the importance of wastewater-based epidemiology (WBE) for public health protection. Beyond COVID-19, it can provide additional value for monitoring and informing on a range of biological and chemical markers of human health. A discussion of measurement uncertainty associated with surveillance of wastewater, focusing on lessons-learned from the UK programmes monitoring COVID-19 is presented, showing that sources of uncertainty impacting measurement quality and interpretation of data for public health decision-making, are varied and complex. While some factors remain poorly understood, we present approaches taken by the UK programmes to manage and mitigate the more tractable sources of uncertainty. This work provides a platform to integrate uncertainty management into WBE activities as part of global One Health initiatives beyond the pandemic.


Asunto(s)
COVID-19 , Pandemias , Humanos , Pandemias/prevención & control , SARS-CoV-2 , Incertidumbre , Aguas Residuales , Monitoreo Epidemiológico Basado en Aguas Residuales
10.
Eur Radiol ; 31(5): 2788-2797, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33128187

RESUMEN

OBJECTIVES: To determine the test-retest reproducibility and observer variability of CMR-derived LA function, using (i) LA strain (LAS) and strain rate (LASR), and (ii) LA volumes (LAV) and emptying fraction (LAEF). METHODS: Sixty participants with and without cardiovascular disease (aortic stenosis (AS) (n = 16), type 2 diabetes (T2D) (n = 28), end-stage renal disease on haemodialysis (n = 10) and healthy volunteers (n = 6)) underwent two separate CMR scans 7-14 days apart. LAS and LASR, corresponding to LA reservoir, conduit and contractile booster-pump function, were assessed using Feature Tracking software (QStrain v2.0). LAEF was calculated using the biplane area length method (QMass v8.1). Both were assessed using 4- and 2-chamber long-axis standard steady-state free precession cine images, and average values were calculated. Intra- and inter-observer variabilities were assessed in 10 randomly selected participants. RESULTS: The test-retest reproducibility was moderate to poor for all strain and strain rate parameters. Overall, strain and strain rate corresponding to reservoir phase (LAS_r, LASR_r) were the most reproducible, yielding the smallest coefficient of variance (CoV) (29.9% for LAS_r, 28.9% for LASR_r). The test-retest reproducibility for LAVs and LAEF was good: LAVmax CoV = 19.6% ICC = 0.89, LAVmin CoV = 27.0% ICC = 0.89 and total LAEF CoV = 15.6% ICC = 0.78. The inter- and intra-observer variabilities were good for all parameters except for conduit function. CONCLUSION: The test-retest reproducibility of LA strain and strain rate assessment by CMR utilising Feature Tracking is moderate to poor across disease states, whereas LA volume and emptying fraction are more reproducible on CMR. Further improvements in LA strain quantification are needed before widespread clinical application. KEY POINTS: • LA strain and strain rate assessment using Feature Tracking on CMR has moderate to poor test-retest reproducibility across disease states. • The test-retest reproducibility for the biplane method of assessing LA function is better than strain assessment, with lower coefficient of variances and narrower limits of agreement on Bland-Altman plots. • Biplane LA volumetric measurement also has better intra- and inter-observer variability compared to strain assessment.


Asunto(s)
Función del Atrio Izquierdo , Diabetes Mellitus Tipo 2 , Atrios Cardíacos/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Imagen por Resonancia Cinemagnética , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados
11.
Sports Med Open ; 6(1): 53, 2020 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-33136207

RESUMEN

BACKGROUND: Cutting actions are associated with non-contact ACL injuries in multidirectional sports due to the propensity to generate large multiplanar knee joint loads (KJLs) that have the capacity to increase ACL loading and strain. Numerous studies have investigated the biomechanical determinants of KJLs in cutting tasks. The aim of this systematic review was to comprehensively review the literature regarding biomechanical determinants of KJLs during cutting, in order to develop a cutting technical framework alongside training recommendations for practitioners regarding KJL mitigation. METHODS: Databases (SPORTDiscus, Web of Science and PubMed) were systematically searched using a combination of the following terms: "Biomechanical determinants", or "Knee abduction moment", or "Technical determinants", or "Knee loading", or "Knee loads", or "Mechanical determinants", or "ACL strain", or "Knee adduction moment", or "Anterior tibial shear", or "Knee internal rotation moment", or "Knee valgus moment" AND "Change of direction", or "Cutting manoeuvre", or "Run and cut", or "Run-and-cut", or "Sidestepping", or "Side-stepping", or "Shuttle run". Inclusion criteria were as follows: studies examining a cutting task < 110° with a preceding approach run that examined biomechanical determinants of KJLs using three-dimensional motion analysis. RESULTS: The search returned 6404 possibly eligible articles, and 6 identified through other sources. Following duplicate removal, 4421 titles and abstracts were screened, leaving 246 full texts to be screened for inclusion. Twenty-three full texts were deemed eligible for inclusion and identified numerous determinants of KJLs; 11 trunk, 11 hip, 7 knee, 3 multiplanar KJLs, 5 foot/ankle and 7 identifying ground reaction forces (GRFs) as determinants of KJLs. CONCLUSION: Using the framework developed from the results, cutting KJLs can be mitigated through the following: reducing lateral foot-plant distances, thus lowering hip abduction and orientating the foot closer to neutral with a mid-foot or forefoot placement strategy; minimising knee valgus and hip internal rotation angles and motion at initial contact (IC) and weight acceptance (WA); avoiding and limiting lateral trunk flexion and attempt to maintain an upright trunk position or trunk lean into the intended direction; and finally, reducing GRF magnitude during WA, potentially by attenuation through increased knee flexion and emphasising a greater proportion of braking during the penultimate foot contact (PFC).

12.
J Appl Biomech ; 36(5): 307-312, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32796136

RESUMEN

The primary purpose of this study was to examine lateral deviations in center of pressure as a result of an extreme-duration load carriage task, with particular focus on heel contact. A total of 20 (n = 17 males and n = 3 females) soldiers from a special operation forces unit (body mass 80.72 [21.49] kg, stature 178.25 [8.75] cm, age 26 [9] y) underwent gait plantar pressure assessment and vertical jump testing before and after a 43-km load carriage event (duration 817.02 [32.66] min) carrying a total external load of 29.80 (1.05) kg. Vertical jump height decreased by 18.62% (16.85%) from 0.30 (0.08) to 0.24 (0.07) m, P < .001. Loading peak and midstance force minimum were significantly increased after load carriage (2.59 [0.51] vs 2.81 [0.61] body weight, P = .035, Glass delta = 0.44 and 1.28 [0.40] vs 1.46 [0.41] body weight, P = .015, Glass delta = 0.45, respectively) and increases in lateral center of pressure displacement were observed as a result of the load carriage task 14.64 (3.62) to 16.97 (3.94) mm, P < .029. In conclusion, load carriage instigated a decrease in neuromuscular function alongside increases in ground reaction forces associated with injury risk and center of pressure changes associated with ankle sprain risk. Practitioners should consider that possible reductions in ankle stability remain once load carriage has been completed, suggesting soldiers are still at increased risk of injury even once the load has been removed.

13.
Sports Biomech ; 19(3): 353-365, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30004302

RESUMEN

During practice and competition, golfers are required to use submaximal effort to hit the ball a given distance, i.e., perform a partial shot. While the full golf swing has undergone extensive research, little has addressed partial shots and the biomechanical modifications golfers employ. This study investigates the biomechanical changes between full and partial swings, and determines if the partial swing is a scaled version of the full swing. Using a repeated measures design, 13 male golfers completed a minimum of 10 swings in the full and partial swing conditions, whilst club, ball, kinematic, and kinetic parameters were recorded. Large and statistically significant reductions in body motion (centre of pressure ellipse: 33.0%, p = 0.004, d = 2.26), combined with moderate reductions in lateral shift (25.5%, p = 0.004, d = 0.33) and smaller reductions in trunk rotation (arm to vertical at top of backswing: 14.1%, p = 0.002, d = 2.58) indicate golfers favour larger reductions in proximal measures, combined with diminished reductions as variables moved distally. Furthermore, the partial swing was not found to be a scaled version of the full swing implying a new approach to coaching practices might be considered.


Asunto(s)
Golf/fisiología , Destreza Motora/fisiología , Adulto , Fenómenos Biomecánicos , Conducta Competitiva/fisiología , Humanos , Cinética , Masculino , Persona de Mediana Edad , Equipo Deportivo , Estudios de Tiempo y Movimiento , Torso/fisiología
15.
Nat Microbiol ; 4(7): 1183-1195, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31086312

RESUMEN

Microorganisms in wastewater treatment plants (WWTPs) are essential for water purification to protect public and environmental health. However, the diversity of microorganisms and the factors that control it are poorly understood. Using a systematic global-sampling effort, we analysed the 16S ribosomal RNA gene sequences from ~1,200 activated sludge samples taken from 269 WWTPs in 23 countries on 6 continents. Our analyses revealed that the global activated sludge bacterial communities contain ~1 billion bacterial phylotypes with a Poisson lognormal diversity distribution. Despite this high diversity, activated sludge has a small, global core bacterial community (n = 28 operational taxonomic units) that is strongly linked to activated sludge performance. Meta-analyses with global datasets associate the activated sludge microbiomes most closely to freshwater populations. In contrast to macroorganism diversity, activated sludge bacterial communities show no latitudinal gradient. Furthermore, their spatial turnover is scale-dependent and appears to be largely driven by stochastic processes (dispersal and drift), although deterministic factors (temperature and organic input) are also important. Our findings enhance our mechanistic understanding of the global diversity and biogeography of activated sludge bacterial communities within a theoretical ecology framework and have important implications for microbial ecology and wastewater treatment processes.


Asunto(s)
Biodiversidad , Microbiota , Aguas del Alcantarillado/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , ADN Bacteriano/genética , Geografía , Microbiota/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Purificación del Agua/estadística & datos numéricos
16.
Hum Factors ; 60(2): 160-171, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29244534

RESUMEN

Objective To assess the acute alterations of anterior infant carriage systems on the ground reaction force experienced during over-ground walking. Background Previous research has identified the alterations in posture and gait associated with an increased anterior load (external or internal); however, the forces applied to the system due to the altered posture during over-ground walking have not been established. Method Thirteen mixed gender participants completed 45 over-ground walking trials at a self-selected pace under three loaded conditions (unloaded, semi-structured carrier 9.9 kg, and structured carrier 9.9 kg). Each trial consisted of a 15-m walkway, centered around a piezoelectric force platform sampling at 1,200 Hz. Differences were assessed between loaded and unloaded conditions and across carriers using paired samples t tests and repeated measures ANOVA. Results Additional load increased all ground reaction force parameters; however, the magnitude of force changes was influenced by carrier structure. The structured carrier displayed increased force magnitudes, a reduction in the time to vertical maximum heel contact, and an increased duration of the flat foot phase in walking gait. Conclusion Evidence suggests that the acute application of anterior infant carriers alters both kinetic and temporal measures of walking gait. Importantly, these changes appear to be governed not solely by the additional mass but also by the structure of the carrier. Application These findings indicate carrier structure should be considered by the wearer and may be used to inform policy in the recommendation of anterior infant carriage systems use by caregivers.


Asunto(s)
Fenómenos Biomecánicos , Equipos y Suministros , Marcha , Soporte de Peso , Adulto , Femenino , Humanos , Lactante , Masculino
17.
PLoS One ; 12(10): e0186364, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29088219

RESUMEN

Malaria causes about half a million deaths annually, with Plasmodium falciparum being responsible for 90% of all the cases. Recent reports on artemisinin resistance in Southeast Asia warrant urgent discovery of novel drugs for the treatment of malaria. However, most bioactive compounds fail to progress to treatments due to safety concerns. Drug repositioning offers an alternative strategy where drugs that have already been approved as safe for other diseases could be used to treat malaria. This study screened approved drugs for antimalarial activity using an in silico chemogenomics approach prior to in vitro verification. All the P. falciparum proteins sequences available in NCBI RefSeq were mined and used to perform a similarity search against DrugBank, TTD and STITCH databases to identify similar putative drug targets. Druggability indices of the potential P. falciparum drug targets were obtained from TDR targets database. Functional amino acid residues of the drug targets were determined using ConSurf server which was used to fine tune the similarity search. This study predicted 133 approved drugs that could target 34 P. falciparum proteins. A literature search done at PubMed and Google Scholar showed 105 out of the 133 drugs to have been previously tested against malaria, with most showing activity. For further validation, drug susceptibility assays using SYBR Green I method were done on a representative group of 10 predicted drugs, eight of which did show activity against P. falciparum 3D7 clone. Seven had IC50 values ranging from 1 µM to 50 µM. This study also suggests drug-target association and hence possible mechanisms of action of drugs that did show antiplasmodial activity. The study results validate the use of proteome-wide target similarity approach in identifying approved drugs with activity against P. falciparum and could be adapted for other pathogens.


Asunto(s)
Antimaláricos/farmacología , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/metabolismo , Proteínas Protozoarias/metabolismo , Secuencia de Aminoácidos , Animales , Antimaláricos/uso terapéutico , Bases de Datos Factuales , Aprobación de Drogas , Técnicas In Vitro , Proteínas Protozoarias/química , Homología de Secuencia de Aminoácido
18.
Open Orthop J ; 11: 979-988, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29114337

RESUMEN

BACKGROUND: Arthroscopy has rapidly transformed the treatment of anterior shoulder instability over the past 30 years. Development of arthroscopic equipment has permitted the investigation and diagnosis of the unstable shoulder, and fixation methods have evolved to promote arthroscopy from an experimental procedure to one of first-line mainstream treatment. METHODS: Key research papers were reviewed to identify the fundamental principles in patient diagnosis and appropriate selection for arthroscopic treatment. The evolution of arthroscopy is described in this article to facilitate the understanding of current treatment. RESULTS: Accurate diagnosis of the shoulder instability subtype is essential prior to selection for surgery. Different surgical techniques are described to address different pathology within the glenohumeral joint related to instability and the appropriate method should be selected accordingly to optimise outcome. CONCLUSION: Anterior shoulder instability can be treated successfully using arthroscopic surgery, but the surgeon must treat each patient as an individual case and recognise the different subtypes of instability, the associated pathological lesions and the limitations of arthroscopy. The article concludes with a suggested algorithm for the treatment of anterior shoulder instability.

19.
J Gastrointest Oncol ; 8(1): E26-E30, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28280633

RESUMEN

Transarterial chemoembolization (TACE) is a therapeutic procedure often performed for hepatocellular carcinoma (HCC). Local complications, though generally uncommon, can arise from arterial ischemia and local cytotoxicity from the chemotherapeutic delivery. We present a case of acute pancreatitis as a rare complication of the TACE procedure along with a review of literature of this uncommon adverse effect.

20.
Curr Opin Nephrol Hypertens ; 24(6): 517-24, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26335554

RESUMEN

PURPOSE OF REVIEW: Epicardial adipose tissue (EAT) is the visceral fat of the heart, sharing many of the pathophysiological properties of other visceral fat depots. EAT is a metabolically active paracrine and vasocrine organ that causes local cardiac inflammation and is strongly implicated in the pathogenesis of coronary atherosclerosis. This article highlights the findings of recent observational studies in patients on haemodialysis that link the quantity of EAT to increased rates of cardiovascular and coronary artery disease and review the proposed methods of pathogenesis and the possible role of EAT quantification to improve cardiovascular risk assessment. RECENT FINDINGS: Increasing volumes of EAT in patients on haemodialysis correlate with increased inflammatory mediators, higher rates of cardiovascular disease and coronary artery calcification, independent of general adiposity. EAT is an independent predictor of mortality and a potentially modifiable target for therapeutic interventions. SUMMARY: EAT is likely to play a central role in the pathogenesis of cardiovascular disease in patients on haemodialysis, adds incrementally to conventional cardiovascular risk stratification models and is a potential target for therapeutic intervention.


Asunto(s)
Tejido Adiposo/patología , Enfermedades Cardiovasculares/patología , Fallo Renal Crónico/patología , Fallo Renal Crónico/terapia , Diálisis Renal , Insuficiencia Renal Crónica/terapia , Tejido Adiposo/metabolismo , Animales , Enfermedades Cardiovasculares/complicaciones , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/diagnóstico , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/patología , Factores de Riesgo
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