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1.
Perspect Public Health ; 143(6): 347-357, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37902308

RESUMO

AIMS: Obesity contributes to morbidity and early mortality, affecting people of all ages and sociodemographic backgrounds. Despite attempts to address obesity, efforts to date have only had limited success. Adopting a whole systems approach (WSA) may potentially address obesity and emphasise complex inter-relating factors beyond individual choice. This study aimed to assess implementation of WSA to diet and healthy weight in two council areas of Scotland, longitudinally exploring enablers and barriers. One area followed a Leeds Beckett WSA model (LBM) of implementation, while the other used a hybrid model incorporating existing working systems. METHODS: To assess the process of implementing a WSA, interviews and focus groups were conducted after initiation and 1 year later. RESULTS: Main enablers included: belief in WSA effectiveness; positive relationships between key personnel; buy-in at community and national levels; funding availability; the working group responsible for coordinating the system development comprising individuals with diverse expertise; good communication; and existing governance structures. Barriers included: insufficient funding; high staff turnover; inadequate training in WSA methodology; engaging all relevant stakeholders and reverting to 'old ways' of non-WSA working. The LBM provided a framework for system setup and generating an action plan. CONCLUSION: This study provides the first independent longitudinal process evaluation of WSAs that have incorporated Leeds Beckett methodology, and offers insights into how a WSA can be implemented to address diet and healthy weight.


Assuntos
Dieta , Obesidade , Humanos , Escócia , Obesidade/epidemiologia , Obesidade/prevenção & controle , Grupos Focais , Análise de Sistemas
2.
Science ; 379(6630): 393-398, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36701449

RESUMO

Rapid evolution remains a largely unrecognized factor in models that forecast the fate of ecosystems under scenarios of global change. In this work, we quantified the roles of heritable variation in plant traits and of trait evolution in explaining variability in forecasts of the state of coastal wetland ecosystems. A common garden study of genotypes of the dominant sedge Schoenoplectus americanus, "resurrected" from time-stratified seed banks, revealed that heritable variation and evolution explained key ecosystem attributes such as the allocation and distribution of belowground biomass. Incorporating heritable trait variation and evolution into an ecosystem model altered predictions of carbon accumulation and soil surface accretion (a determinant of marsh resilience to sea level rise), demonstrating the importance of accounting for evolutionary processes when forecasting ecosystem dynamics.


Assuntos
Plantas , Elevação do Nível do Mar , Áreas Alagadas , Plantas/genética , Solo
4.
J Phys Chem A ; 124(35): 7031-7046, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32786976

RESUMO

Thin films of pentaerythritol tetranitrate (PETN) were shock compressed using the laser driven shock apparatus at Los Alamos National Laboratory (LANL). Two spectroscopic probes were available to this apparatus: visible white light transient absorption spectroscopy (VIS) from 400 to 700 nm and mid-infrared transient absorption spectroscopy (MIR) from 1150 to 3800 cm-1. Important PETN vibrational modes are the symmetric and antisymmetric NO2 stretches at 1280 and 1650 cm-1, respectively, as well as CH stretches at ∼2900 cm-1. Shock strength was varied from approximately 3 to 55 GPa to span from the chemically unreactive regime to the regime in which fast chemical reaction took place on the 250 ps time scale of the measurements. VIS and MIR results suggest irreversible chemistry was induced in PETN at pressures above 30 GPa. At lower shock pressures, the spectroscopy showed minimal changes attributable to pressure induced effects. Under the higher-pressure reactive conditions, the frequency region at the antisymmetric NO2 stretch mode had a significantly increased absorption while the region around the symmetric NO2 stretch did not. No observable increased absorption occurred in the higher frequency regions where CH-, NH-, and OH- bond absorptions would be observed. A broad absorption appeared on the shoulder at the red-edge of the CO2 vibrational band around 2200 cm-1. In addition to the experiments, reactive molecular dynamics were carried out under equivalent shock conditions to correlate the evolution of the infrared spectrum to molecular processes. The simulations show results consistent to experiments up to 30 GPa but suggest that NO and NO2 related features provided the strongest contributions to the shocked infrared changes. Proposed mechanisms for shocked PETN chemistry are analyzed as consistent or inconsistent with the data presented here. Our experimental data suggests C≡O or N2O bond formation, nitrite formation, and absence of significant hydroxyl or amine concentrations in the initial chemistry steps in PETN shocked above 30 GPa.

5.
Rev Sci Instrum ; 90(6): 063001, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31254979

RESUMO

Common Ti:sapphire chirped pulse amplified laser systems can be readily adapted to be both a generator of adjustable pressure shock waves and a source for multiple probes of the ensuing ultrafast shock dynamics. In this paper, we detail experimental considerations for optimizing the shock generation, interferometric characterization, and spectroscopic probing of shock dynamics with visible and mid-infrared transient absorption. While we have reported results using these techniques elsewhere, here we detail how the spectroscopies are integrated with the shock and interferometry experiment. The interferometric characterization uses information from beams at multiple polarizations and angles of incidence combined with thin film equations and shock dynamics to determine the shock velocity, particle velocity, and shocked refractive index. Visible transient absorption spectroscopy uses a white light supercontinuum in a reflection geometry, synchronized to the shock wave, to time resolve shock-induced changes in visible absorption such as changes to electronic structure or strongly absorbing products and intermediates due to reaction. Mid-infrared transient absorption spectroscopy uses two color filamentation supercontinuum generation combined with a simple thermal imaging microbolometer spectrometer to enable broadband single shot detection of changes in the vibrational spectra. These methods are demonstrated here in the study of shock dynamics at stresses from 5 to 30 GPa in organic materials and from a few GPa to >70 GPa in metals with spatial resolution of a few micrometers and temporal resolution of a few picoseconds. This experiment would be possible to replicate in any ultrafast laser laboratory containing a single bench top commercial chirped pulse amplification laser system.

6.
Restor Neurol Neurosci ; 37(3): 273-290, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31227676

RESUMO

BACKGROUND: In individuals with chronic stroke, impairment of the paretic arm may be exacerbated by increased contralesional transcallosal inhibition (TCI). Continuous theta burst stimulation (cTBS) can decrease primary motor cortex (M1) excitability and TCI. However, contralesional cTBS shows inconsistent effects after stroke. Variable effects of cTBS could stem from failure to pair stimulation with skilled motor practice or a focus of applying cTBS over M1. OBJECTIVE: Here, we investigated the effects of pairing cTBS with skilled practice on motor learning and arm function. We considered the differential effects of stimulation over two different brain regions: contralesional M1 (M1c) or contralesional primary somatosensory cortex (S1c). METHODS: 37 individuals with chronic stroke participated in five sessions of cTBS and paretic arm skilled practice of a serial targeting task (STT); participants received either cTBS over M1c or S1c or sham before STT practice. Changes in STT performance and Wolf Motor Function Test (WMFT) were assessed as primary outcomes. Assessment of bilateral corticospinal, intracortical excitability and TCI were secondary outcomes. RESULTS: cTBS over sensorimotor cortex did not improve STT performance and paretic WMFT-rate beyond sham cTBS. TCI was reduced bi-directionally following the intervention, regardless of stimulation group. In addition, we observed an association between STT performance change and paretic WMFT-rate change in the M1c stimulation group only. CONCLUSIONS: Multiple sessions of STT practice can improve paretic arm function and decrease TCI bilaterally, with no additional benefit of prior cTBS. Our results suggest that improvement in STT practice following M1c cTBS scaled with change in paretic arm function in some individuals. Our results highlight the need for a better understanding of the mechanisms of cTBS to effectively identify who may benefit from this form of brain stimulation.


Assuntos
Braço/fisiopatologia , Excitabilidade Cortical/fisiologia , Córtex Motor/fisiopatologia , Destreza Motora/fisiologia , Inibição Neural/fisiologia , Paresia/reabilitação , Prática Psicológica , Córtex Somatossensorial/fisiopatologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/terapia , Estimulação Magnética Transcraniana , Idoso , Doença Crônica , Corpo Caloso/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paresia/etiologia , Paresia/fisiopatologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento
7.
Public Health ; 171: 123-130, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31128557

RESUMO

OBJECTIVE: Smokers who access free National Health Service (NHS) Stop Smoking Services (SSS) in the UK are four times more likely to stop smoking, yet uptake of the services has been in decline in recent years. Evidence was collated to explore the beliefs of smokers, ex-smokers and Stop Smoking Advisors (SSAs) about SSS and the barriers and facilitators to access. STUDY DESIGN: Mixed-methods design including i) a search of the literature; ii) a cross-sectional online questionnaire completed by 38 smokers and ex-smokers; and iii) semistructured interviews with 5 SSAs. METHODS: PubMed, Web of Science, Scopus, Prospero and the NIHR Portfolio were searched in October 2017 to identify relevant studies. Smokers and ex-smokers were recruited to the online questionnaire via Public Health websites and social media in Warwickshire. SSAs identified via Public Health Warwickshire were invited to take part in an interview conducted over the telephone. Findings were collated and analysed using the COM-B ('Capability', 'Opportunity', 'Motivation' and 'Behaviour') model framework. RESULTS: A range of practical and psychological or belief-based barriers and facilitators to accessing SSS were identified within all the components of the COM-B model, aside from physical capability, for example; 'Psychological capability', such as lack of understanding about what the service offers; 'Reflective motivation', such as lack of confidence in service efficacy; and 'Social opportunity', such as recommendations from healthcare professionals to attend. Suggestions and consideration on how future tobacco control intervention and public health messages can address these components are reported. CONCLUSIONS: Public health interventions and campaigns may benefit from focussing on addressing the well-known perceived barriers and facilitators smokers experience, in particular focussing on the components of the COM-B that have been identified as being important to increase the uptake of SSS.


Assuntos
Atitude Frente a Saúde , Conselheiros/psicologia , Ex-Fumantes/psicologia , Acessibilidade aos Serviços de Saúde , Fumantes/psicologia , Prevenção do Hábito de Fumar , Medicina Estatal , Adolescente , Adulto , Idoso , Conselheiros/estatística & dados numéricos , Estudos Transversais , Ex-Fumantes/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fumantes/estatística & dados numéricos , Reino Unido , Adulto Jovem
8.
Neural Plast ; 2019: 7092496, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863437

RESUMO

Continuous theta burst stimulation (cTBS) is a form of noninvasive repetitive brain stimulation that, when delivered over the contralesional hemisphere, can influence the excitability of the ipsilesional hemisphere in individuals with stroke. cTBS applied prior to skilled motor practice interventions may augment motor learning; however, there is a high degree of variability in individual response to this intervention. The main objective of the present study was to assess white matter biomarkers of response to cTBS paired with skilled motor practice in individuals with chronic stroke. We tested the effects of stimulation of the contralesional hemisphere at the site of the primary motor cortex (M1c) or primary somatosensory cortex (S1c) and a third group who received sham stimulation. Within each stimulation group, individuals were categorized into responders or nonresponders based on their capacity for motor skill change. Baseline diffusion tensor imaging (DTI) indexed the underlying white matter microstructure of a previously known motor learning network, named the constrained motor connectome (CMC), as well as the corticospinal tract (CST) of lesioned and nonlesioned hemispheres. Across practice, there were no differential group effects. However, when categorized as responders vs. nonresponders using change in motor behaviour, we demonstrated a significant difference in CMC microstructural properties (as measured by fractional anisotropy (FA)) for individuals in M1c and S1c groups. There were no significant differences between responders and nonresponders in clinical baseline measures or microstructural properties (FA) in the CST. The present study identifies a white matter biomarker, which extends beyond the CST, advancing our understanding of the importance of white matter networks for motor after stroke.


Assuntos
Terapia por Estimulação Elétrica/métodos , Córtex Motor/diagnóstico por imagem , Córtex Somatossensorial/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Idoso , Biomarcadores , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/terapia , Resultado do Tratamento
9.
Exp Gerontol ; 112: 1-8, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30114481

RESUMO

Sensorimotor integration is the process through which somatosensory information is incorporated to inform motor output. Given its important behavioural implications, understanding the influence of healthy aging on the underlying neurophysiology of sensorimotor integration and whether it is modifiable through intervention is important. The aims of the current work were to: 1) profile aging-related differences in sensorimotor integration, and 2) to determine if sensorimotor integration in older adults can be modulated in response to sensory training. A group of older healthy individuals and younger healthy individuals participated in two experimental sessions. First, baseline neurophysiology of sensorimotor integration was assessed. Short-latency afferent inhibition, afferent facilitation, and long-latency afferent inhibition provided nerve-based assessment of sensorimotor integration. Vibration-based measures of sensorimotor integration combined vibration of abductor pollicis brevis with single and paired-pulse transcranial magnetic stimulation techniques. In the second experimental session, a 15-min block of sensory training designed to modulate sensorimotor integration preceded the same neurophysiological assessment. Results indicate that there are aging-related differences in nerve-based measures of sensorimotor integration, specifically short- and long-latency afferent inhibition. In contrast, there are not aging-related differences when peripheral muscle belly vibration is used to probe sensorimotor integration. Following sensory training there is a reduction in the cortical response to vibration. These results suggest that there is differential aging-related modulation of sensorimotor integration, based on the type of afferent information. Additionally, sensorimotor integration is modifiable with a single session of sensory training, and this ability for neuroplastic change is retained with healthy aging.


Assuntos
Potencial Evocado Motor , Potenciais Somatossensoriais Evocados , Mãos/fisiologia , Envelhecimento Saudável/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiologia , Plasticidade Neuronal , Estimulação Magnética Transcraniana , Vibração , Adulto Jovem
10.
J Evol Biol ; 31(1): 46-56, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29030895

RESUMO

Antagonistic pleiotropy (AP) is a genetic trade-off between different fitness components. In annual plants, a trade-off between days to flower (DTF) and reproductive capacity often determines how many individuals survive to flower in a short growing season, and also influences the seed set of survivors. We develop a model of viability and fecundity selection informed by many experiments on the yellow monkeyflower, Mimulus guttatus, but applicable to many annual species. A viability/fecundity trade-off maintains stable polymorphism under surprisingly general conditions. We also introduce both spatial heterogeneity and temporal stochasticity in environmental parameters. Neither is necessary for polymorphism, but spatial heterogeneity allows polymorphism while also generating the often observed non-negative correlations in fitness components.


Assuntos
Aptidão Genética/fisiologia , Pleiotropia Genética , Mimulus/fisiologia , Modelos Biológicos , Mimulus/genética
11.
Brain Stimul ; 10(6): 1102-1111, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28807846

RESUMO

BACKGROUND: Electrophysiological measures can help understand brain function both in healthy individuals and in the context of a disease. Given the amount of information that can be extracted from these measures and their frequent use, it is essential to know more about their inherent reliability. OBJECTIVE/HYPOTHESIS: To understand the reliability of electrophysiology measures in healthy individuals. We hypothesized that measures of threshold and latency would be the most reliable and least susceptible to methodological differences between study sites. METHODS: Somatosensory evoked potentials from 112 control participants; long-latency reflexes, transcranial magnetic stimulation with resting and active motor thresholds, motor evoked potential latencies, input/output curves, and short-latency sensory afferent inhibition and facilitation from 84 controls were collected at 3 visits over 24 months at 4 Track-On HD study sites. Reliability was assessed using intra-class correlation coefficients for absolute agreement, and the effects of reliability on statistical power are demonstrated for different sample sizes and study designs. RESULTS: Measures quantifying latencies, thresholds, and evoked responses at high stimulator intensities had the highest reliability, and required the smallest sample sizes to adequately power a study. Very few between-site differences were detected. CONCLUSIONS: Reliability and susceptibility to between-site differences should be evaluated for electrophysiological measures before including them in study designs. Levels of reliability vary substantially across electrophysiological measures, though there are few between-site differences. To address this, reliability should be used in conjunction with theoretical calculations to inform sample size and ensure studies are adequately powered to detect true change in measures of interest.


Assuntos
Potencial Evocado Motor/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Estimulação Magnética Transcraniana/métodos , Estimulação Magnética Transcraniana/normas , Adulto , Estudos de Coortes , Fenômenos Eletrofisiológicos/fisiologia , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Descanso/fisiologia
12.
Epidemiol Infect ; 145(12): 2618-2625, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28748773

RESUMO

Varicella-zoster virus (VZV) infection (chickenpox) results in latency and subsequent reactivation manifests as shingles. Effective attenuated vaccines (vOka) are available for prevention of both illnesses. In this study, an amplicon-based sequencing method capable of differentiating between VZV wild-type (wt) strains and vOka vaccine is described. A total of 44 vesicular fluid specimens collected from 43 patients (16 from China and 27 from the UK) with either chickenpox or shingles were investigated, of which 10 had received previous vaccination. Four sets of polymerase chain reactions were set up simultaneously with primers amplifying regions encompassing four single nucleotide polymorphisms (SNPs), '69349-106262-107252-108111'. Nucleotide sequences were generated by Sanger sequencing. All samples except one had a wt SNP profile of 'A-T-T-T'. The sample collected from a patient who received vaccine 7-10 days ago, along with VZV vaccine preparations, Zostavax and Baike-varicella gave a SNP profile 'G-C-C-C'. The results show that this method can distinguish vaccine-derived virus from wt viruses from main four clades, (clades 1-4) and should be of utility worldwide.


Assuntos
Vacina contra Varicela/genética , Herpesvirus Humano 3/genética , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Varicela/virologia , Vacina contra Varicela/classificação , Criança , Pré-Escolar , China , Inglaterra , Feminino , Herpes Zoster/virologia , Herpesvirus Humano 3/classificação , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Escócia , Análise de Sequência de DNA , Vacinas Atenuadas/classificação , Vacinas Atenuadas/genética , Adulto Jovem
13.
Clin Microbiol Infect ; 23(8): 516-523, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28712666

RESUMO

BACKGROUND: The WHO European Region (EUR) has adopted the goal of eliminating measles and rubella but individual countries perform differently in achieving this goal. Measles virus spread across the EUR by mobile groups has recently led to large outbreaks in the insufficiently vaccinated resident population. As an instrument for monitoring the elimination process and verifying the interruption of endemic virus transmission, molecular surveillance has to provide valid and representative data. Irrespective of the country's specific situation, it is required to ensure the functionality of the laboratory surveillance that is supported by the WHO Global Measles and Rubella Laboratory Network. AIMS: To investigate whether the molecular surveillance in the EUR is adequate for the challenges in the elimination phase, we addressed the quality assurance of molecular data, the continuity and intensity of molecular monitoring, and the analysis of transmission chains. SOURCES: Published articles, the molecular External Quality Assessment Programme of the WHO, the Centralized Information System for Infectious Diseases of the WHO EUR and the WHO Measles and Rubella Nucleotide Surveillance databases served as information sources. CONTENT: Molecular proficiency testing conducted by the WHO in 2016 has shown that the expertise for measles and rubella virus genotyping exists in all parts of the EUR. The analysis of surveillance data reported nationally to the WHO in 2013-2016 has revealed some countries with outbreaks but not sufficiently representative molecular data. Long-lasting supranational MV transmission chains were identified. IMPLICATIONS: A more systematic molecular monitoring and recording of the transmission pattern for the whole EUR could help to create a meaningful picture of the elimination process.


Assuntos
Monitoramento Epidemiológico , Vírus do Sarampo/isolamento & purificação , Sarampo/epidemiologia , Vírus da Rubéola/isolamento & purificação , Rubéola (Sarampo Alemão)/epidemiologia , Surtos de Doenças , Transmissão de Doença Infecciosa , Europa (Continente)/epidemiologia , Técnicas de Genotipagem/métodos , Técnicas de Genotipagem/normas , Humanos , Ensaio de Proficiência Laboratorial , Sarampo/transmissão , Vírus do Sarampo/classificação , Vírus do Sarampo/genética , Epidemiologia Molecular/métodos , Epidemiologia Molecular/normas , Rubéola (Sarampo Alemão)/transmissão , Vírus da Rubéola/classificação , Vírus da Rubéola/genética , Organização Mundial da Saúde
14.
Epidemiol Infect ; 145(9): 1855-1864, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28367789

RESUMO

In autumn 2014, enterovirus D68 (EV-D68) cases presenting with severe respiratory or neurological disease were described in countries worldwide. To describe the epidemiology and virological characteristics of EV-D68 in England, we collected clinical information on laboratory-confirmed EV-D68 cases detected in secondary care (hospitals), between September 2014 and January 2015. In primary care (general practitioners), respiratory swabs collected (September 2013-January 2015) from patients presenting with influenza-like illness were tested for EV-D68. In secondary care 55 EV-D68 cases were detected. Among those, 45 cases had clinical information available and 89% (40/45) presented with severe respiratory symptoms. Detection of EV-D68 among patients in primary care increased from 0.4% (4/1074; 95% CI 0.1-1.0) (September 2013-January 2014) to 0.8% (11/1359; 95% CI 0.4-1.5) (September 2014-January 2015). Characterization of EV-D68 strains circulating in England since 2012 and up to winter 2014/2015 indicated that those strains were genetically similar to those detected in 2014 in USA. We recommend reinforcing enterovirus surveillance through screening respiratory samples of suspected cases.


Assuntos
Enterovirus Humano D/isolamento & purificação , Infecções por Enterovirus/epidemiologia , Infecções Respiratórias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Inglaterra/epidemiologia , Infecções por Enterovirus/diagnóstico , Infecções por Enterovirus/virologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Filogenia , Prevalência , Atenção Primária à Saúde , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/virologia , Estações do Ano , Atenção Secundária à Saúde , Proteínas Virais de Fusão/genética , Adulto Jovem
15.
Eur J Neurosci ; 45(10): 1343-1355, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28370664

RESUMO

Primary motor cortex (M1) excitability is modulated following a single session of cycling exercise. Specifically, short-interval intracortical inhibition and intracortical facilitation are altered following a session of cycling, suggesting that exercise affects the excitability of varied cortical circuits. Yet we do not know whether a session of exercise also impacts the excitability of interhemispheric circuits between, and other intracortical circuits within, M1. Here we present two experiments designed to address this gap in knowledge. In experiment 1, single and paired pulse transcranial magnetic stimulation (TMS) were used to measure intracortical circuits including, short-interval intracortical facilitation (SICF) tested at 1.1, 1.5, 2.7, 3.1 and 4.5 ms interstimulus intervals (ISIs), contralateral silent period (CSP) and interhemispheric interactions by measuring transcallosal inhibition (TCI) recorded from the abductor pollicus brevis muscles. All circuits were assessed bilaterally pre and two time points post (immediately, 30 min) moderate intensity lower limb cycling. SICF was enhanced in the left hemisphere after exercise at the 1.5 ms ISI. Also, CSP was shortened and TCI decreased bilaterally after exercise. In Experiment 2, corticospinal and spinal excitability were tested before and after exercise to investigate the locus of the effects found in Experiment 1. Exercise did not impact motor-evoked potential recruitment curves, Hoffman reflex or V-wave amplitudes. These results suggest that a session of exercise decreases intracortical and interhemispheric inhibition and increases facilitation in multiple circuits within M1, without concurrently altering spinal excitability. These findings have implications for developing exercise strategies designed to potentiate M1 plasticity and skill learning in healthy and clinical populations.


Assuntos
Exercício Físico , Lateralidade Funcional , Córtex Motor/fisiologia , Adulto , Corpo Caloso/fisiologia , Humanos , Inibição Neural , Tratos Piramidais/fisiologia
16.
Clin Microbiol Infect ; 23(8): 511-515, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28412379

RESUMO

The Member States of the WHO European Region adopted the goal of measles and rubella elimination more than 10 years ago, but so far only 21 of 53 countries have reached this target. Laboratory investigation of suspected cases is essential to support disease elimination efforts. Therefore, WHO maintains a network of accredited laboratories providing high-quality testing. Laboratory investigation heavily relies on specific IgM serology and increasingly on virus detection by reverse transcription (RT)-PCR, but other methods such as IgG avidity testing and genetic characterization of virus strains have gained in importance. In elimination settings, often few samples from suspected cases are available for testing, but testing proficiency must be maintained. The predictive value of an IgM-positive result decreases and other rash-fever disease aetiologies become more important. In addition, cases with a rash after measles/rubella vaccination or with mild disease after waning of vaccine-induced antibodies are seen more often. Thus, it is necessary to perform comprehensive and potentially time-consuming and costly investigations of every suspected case using quality-controlled laboratory methods. At the same time rapid feedback to public health officers is required for timely interventions. The introduction of new laboratory methods for comprehensive case investigations requires training of staff under the supervision of WHO-accredited reference laboratories and the definition of appropriate test algorithms. Clinical, laboratory, and epidemiological data are essential for final case classification and investigation of chains of transmission in the endgame of measles and rubella elimination.


Assuntos
Sarampo/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Rubéola (Sarampo Alemão)/diagnóstico , Testes Sorológicos/métodos , Erradicação de Doenças/organização & administração , Métodos Epidemiológicos , Europa (Continente)/epidemiologia , Humanos , Sarampo/epidemiologia , Rubéola (Sarampo Alemão)/epidemiologia , Organização Mundial da Saúde
17.
Nature ; 540(7631): 104-108, 2016 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27905442

RESUMO

The majority of the Earth's terrestrial carbon is stored in the soil. If anthropogenic warming stimulates the loss of this carbon to the atmosphere, it could drive further planetary warming. Despite evidence that warming enhances carbon fluxes to and from the soil, the net global balance between these responses remains uncertain. Here we present a comprehensive analysis of warming-induced changes in soil carbon stocks by assembling data from 49 field experiments located across North America, Europe and Asia. We find that the effects of warming are contingent on the size of the initial soil carbon stock, with considerable losses occurring in high-latitude areas. By extrapolating this empirical relationship to the global scale, we provide estimates of soil carbon sensitivity to warming that may help to constrain Earth system model projections. Our empirical relationship suggests that global soil carbon stocks in the upper soil horizons will fall by 30 ± 30 petagrams of carbon to 203 ± 161 petagrams of carbon under one degree of warming, depending on the rate at which the effects of warming are realized. Under the conservative assumption that the response of soil carbon to warming occurs within a year, a business-as-usual climate scenario would drive the loss of 55 ± 50 petagrams of carbon from the upper soil horizons by 2050. This value is around 12-17 per cent of the expected anthropogenic emissions over this period. Despite the considerable uncertainty in our estimates, the direction of the global soil carbon response is consistent across all scenarios. This provides strong empirical support for the idea that rising temperatures will stimulate the net loss of soil carbon to the atmosphere, driving a positive land carbon-climate feedback that could accelerate climate change.


Assuntos
Atmosfera/química , Ciclo do Carbono , Carbono/análise , Geografia , Aquecimento Global , Solo/química , Bases de Dados Factuais , Ecossistema , Retroalimentação , Modelos Estatísticos , Reprodutibilidade dos Testes , Temperatura
18.
Epidemiol Infect ; 144(11): 2345-53, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27018820

RESUMO

Healthcare workers (HCWs) reporting no history of varicella frequently receive varicella vaccination (vOka) if they test varicella-zoster virus (VZV) immunoglobulin G (IgG) negative. In this study, the utilities of VZV-IgG time-resolved fluorescence immunoassay (VZV-TRFIA) and a commercial VZV-IgG purified glycoprotein enzyme immunoassay (gpEIA) currently used in England for confirming VZV immunity have been compared to the fluorescent-antibody-to-membrane-antigen assay (FAMA). A total of 110 HCWs received two doses of vOka vaccine spaced 6 weeks apart and sera collected pre-vaccination (n = 100), at 6 weeks post-completion of vaccination (n = 86) and at 12-18 months follow-up (n = 73) were analysed. Pre-vaccination, by FAMA, 61·0% sera were VZV IgG negative, and compared to FAMA the sensitivities of VZV-TRFIA and gpEIA were 74·4% [95% confidence interval (CI) 57·9-87·0] and 46·2% (95% CI 30·1-62·8), respectively. Post-completion of vaccination the seroconversion rate by FAMA was 93·7% compared to rates of 95·8% and 70·8% determined by VZV-TRFIA and gpEIA, respectively. At 12-18 months follow-up seropositivity rates by FAMA, VZV-TRFIA and gpEIA were 78·1%, 74·0% and 47·9%, respectively. Compared to FAMA the sensitivities of VZV-TRFIA and gpEIA for measuring VZV IgG following vaccination were 96·4% (95% CI 91·7-98·8) and 74·6% (95% CI 66·5-81·6), respectively. Using both FAMA and VZV-TRFIA to identify healthy adult VZV susceptibles and measure seroconversion showed that vOka vaccination of HCWs is highly immunogenic.


Assuntos
Anticorpos Antivirais/sangue , Imunofluorescência , Fluorimunoensaio , Pessoal de Saúde/estatística & dados numéricos , Técnicas Imunoenzimáticas , Imunoglobulina G/sangue , Adulto , Vacina contra Varicela/imunologia , Herpesvirus Humano 3/imunologia , Humanos , Pessoa de Meia-Idade , Adulto Jovem
19.
Health Educ Res ; 31(2): 273-82, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26928566

RESUMO

Sexual health service access is fundamental to good sexual health, yet interventions designed to address this have rarely been implemented or evaluated. In this article, pilot evaluation findings for a targeted public health behavior change intervention, delivered via a website and web-app, aiming to increase uptake of sexual health services among 13-19-year olds are reported. A pre-post questionnaire-based design was used. Matched baseline and follow-up data were identified from 148 respondents aged 13-18 years. Outcome measures were self-reported service access, self-reported intention to access services and beliefs about services and service access identified through needs analysis. Objective service access data provided by local sexual health services were also analyzed. Analysis suggests the intervention had a significant positive effect on psychological barriers to and antecedents of service access among females. Males, who reported greater confidence in service access compared with females, significantly increased service access by time 2 follow-up. Available objective service access data support the assertion that the intervention may have led to increases in service access. There is real promise for this novel digital intervention. Further evaluation is planned as the model is licensed to and rolled out by other local authorities in the United Kingdom.


Assuntos
Acessibilidade aos Serviços de Saúde/organização & administração , Internet , Serviços de Saúde Reprodutiva/organização & administração , Adolescente , Feminino , Humanos , Comportamento de Busca de Informação , Masculino , Aplicativos Móveis , Projetos Piloto , Fatores Sexuais , Comportamento Sexual , Reino Unido
20.
Behav Brain Res ; 297: 187-95, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26467603

RESUMO

In individuals with multiple sclerosis (MS), transcranial magnetic stimulation (TMS) may be employed to assess the integrity of corticospinal system and provides a potential surrogate biomarker of disability. The purpose of this study was to provide a comprehensive examination of the relationship between multiple measures corticospinal excitability and clinical disability in MS (expanded disability status scale (EDSS)). Bilateral corticospinal excitability was assessed using motor evoked potential (MEP) input-output (IO) curves, cortical silent period (CSP), short-interval intracortical inhibition (SICI), intracortical facilitation (ICF) and transcallosal inhibition (TCI) in 26 individuals with MS and 11 healthy controls. Measures of corticospinal excitability were compared between individuals with MS and controls. We evaluated the relationship(s) between age and clinical demographics such as age at MS onset (AO), disease duration (DD) and clinical disability (EDSS) with measures of corticospinal excitability. Corticospinal excitability thresholds were higher, MEP latency and CSP onset delayed and MEP durations prolonged in individuals with MS compared to controls. Age, DD and EDSS correlated with corticospinal excitability thresholds. Also, TCI duration and the linear slope of the MEP amplitude IO curve correlated with EDSS. Hierarchical regression modeling demonstrated that combining multiple TMS-based measures of corticospinal excitability accounted for unique variance in clinical disability (EDSS) beyond that of clinical demographics (AO, DD). Our results indicate that multiple TMS-based measures of corticospinal and interhemispheric excitability provide insights into the potential neural mechanisms associated with clinical disability in MS. These findings may aid in the clinical evaluation, disease monitoring and prediction of disability in MS.


Assuntos
Encéfalo/fisiopatologia , Potencial Evocado Motor , Esclerose Múltipla/fisiopatologia , Músculo Esquelético/fisiopatologia , Tratos Piramidais/fisiopatologia , Adulto , Idade de Início , Envelhecimento/fisiologia , Avaliação da Deficiência , Eletromiografia , Feminino , Lateralidade Funcional , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Tempo , Estimulação Magnética Transcraniana
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