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3.
Perspect Public Health ; : 17579139231185999, 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37572017

RESUMO

AIMS: Unintentional injuries in the home contribute substantially to preschool child morbidity and mortality. Practitioners such as health visitors, family mentors and children's centre staff are well-positioned to facilitate child injury prevention by providing home safety advice to families, and training may enhance their ability to do so. We aimed to assess the impact of child home safety training for these practitioners. METHODS: An explanatory mixed-methods design was used. Practitioners completed questionnaires before, and up to 7 months after, receiving child home safety training and took part in interviews. Seventy-eight health visitors, 72 family mentors and 11 children's centre staff members completed questionnaires. Items were used to calculate scores on home safety knowledge, confidence to provide home safety advice and belief that child home safety promotion is important. Thematic analysis of interviews with seven health visitors and nine family mentors, open-ended responses to the questionnaires and an additional evaluation form was conducted to explore attendees' perceptions of the training and its impact. In addition, seven health visitors and six children's centre staff who had received no training were interviewed. RESULTS: Knowledge was greater post-training than pre-training across all participants (p < .001). When practitioner groups were analysed separately, there were significant increases in family mentors' knowledge (p < .001) and belief (p = .016), and health visitors' confidence (p = .0036). Qualitative findings indicated that most training session attendees valued the training, believed their practice relating to child home safety had improved as a result, and felt further similar training sessions would be beneficial. Those who had not attended the sessions described a need for more child home safety training. CONCLUSIONS: Delivering training to practitioners providing child home safety promotion to families with preschool children can enhance injury prevention knowledge, beliefs and confidence and positively impact on home safety promotion by practitioners.

4.
Biomed Phys Eng Express ; 9(5)2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37567152

RESUMO

Objective. This work sets out the capabilities of the high energy proton research beamline developed in the Christie proton therapy centre for Ultra-High Dose Rate (UHDR) irradiation and FLASH experiments. It also characterises the lower limits of UHDR operation for this Pencil Beam Scanning (PBS) proton hardware.Approach. Energy dependent nozzle transmission was measured using a Faraday Cup beam collector. Spot size was measured at the reference plane using a 2D scintillation detector. Integrated depth doses (IDDs) were measured. EBT3 Gafchromic film was used to compare UHDR and conventional dose rate spots. Our beam monitor calibration methodolgy for UHDR is described. A microDiamond detector was used to determine dose rates at zref. Instantaneous depth dose rates were calculated for 70-245 MeV. PBS dose rate distributions were calculated using Folkerts and Van der Water definitions.Main results. Transmission of 7.05 ± 0.1% is achieveable corresponding to a peak instantaneous dose rate of 112.7 Gy s-1. Beam parameters are comparable in conventional and UHDR mode with a spot size ofσx= 4.6 mm,σy= 6.6 mm. Dead time in the beam monitoring electonics warrants a beam current dependent MU correction in the present configuration. Fast beam scanning of 26.4 m s-1(X) and 12.1 m s-1(Y) allows PBS dose rates of the order tens of Grays per second.Significance. UHDR delivery is possible for small field sizes and high energies enabling research into the FLASH effect with PBS protons at our facility. To our knowledge this is also the first thorough characterisation of UHDR irradiation using the hardware of this clinical accelerator at energies less than 250 MeV. The data set out in this publication can be used for designing experiments at this UK research facility and inform the possible future clinical translation of UHDR PBS proton therapy.


Assuntos
Terapia com Prótons , Prótons , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador , Reino Unido
5.
Front Microbiol ; 14: 1208301, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426014

RESUMO

Introduction: Dirofilariasis, including heartworm disease, is a major emergent veterinary parasitic infection and a human zoonosis. Currently, experimental infections of cats and dogs are used in veterinary heartworm preclinical drug research. Methods: As a refined alternative in vivo heartworm preventative drug screen, we assessed lymphopenic mouse strains with ablation of the interleukin-2/7 common gamma chain (γc) as susceptible to the larval development phase of Dirofilaria immitis. Results: Non-obese diabetic (NOD) severe combined immunodeficiency (SCID)γc-/- (NSG and NXG) and recombination-activating gene (RAG)2-/-γc-/- mouse strains yielded viable D. immitis larvae at 2-4 weeks post-infection, including the use of different batches of D. immitis infectious larvae, different D. immitis isolates, and at different laboratories. Mice did not display any clinical signs associated with infection for up to 4 weeks. Developing larvae were found in subcutaneous and muscle fascia tissues, which is the natural site of this stage of heartworm in dogs. Compared with in vitro-propagated larvae at day 14, in vivo-derived larvae had completed the L4 molt, were significantly larger, and contained expanded Wolbachia endobacteria titres. We established an ex vivo L4 paralytic screening system whereby assays with moxidectin or levamisole highlighted discrepancies in relative drug sensitivities in comparison with in vitro-reared L4 D. immitis. We demonstrated effective depletion of Wolbachia by 70%-90% in D. immitis L4 following 2- to 7-day oral in vivo exposures of NSG- or NXG-infected mice with doxycycline or the rapid-acting investigational drug, AWZ1066S. We validated NSG and NXG D. immitis mouse models as a filaricide screen by in vivo treatments with single injections of moxidectin, which mediated a 60%-88% reduction in L4 larvae at 14-28 days. Discussion: Future adoption of these mouse models will benefit end-user laboratories conducting research and development of novel heartworm preventatives via increased access, rapid turnaround, and reduced costs and may simultaneously decrease the need for experimental cat or dog use.

6.
Hum Mov Sci ; 66: 504-510, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203020

RESUMO

Turning while walking is a crucial component of locomotion, often performed on irregular surfaces with little planning time. Turns can be difficult for some older adults due to physiological age-related changes. Two different turning strategies have been identified in the literature. During step turns, which are biomechanically stable, the body rotates about the outside limb, while for spin turns, generally performed with closer foot-to-foot distance, the inside limb is the main pivot point. Turning strategy preferences of older adults under challenging conditions remains unclear. The aim of this study was to determine how turning strategy preference in healthy older adults is modulated by surface features, cueing time, physiological characteristics of aging, and gait parameters. Seventeen healthy older adults (71.5 ±â€¯4.2 years) performed 90° turns for two surfaces (flat, uneven) and two cue conditions (pre-planned, late-cue). Gait parameters were identified from kinematic data. Measures of lower-limb strength, balance, and reaction-time were also recorded. Generalized linear (logistic) regression mixed-effects models examined the effect of (1) surface and cuing, (2) physiological characteristics of ageing, and (3) gait parameters on turn strategy preference. Step turns were preferred when the condition was pre-planned (p < 0.001) (model 1) and when the gait parameters of stride regularity and maximum acceleration decreased (p = 0.010 and p = 0.039, respectively) (model 3). Differences in turn strategy selection under dynamic conditions ought to be evaluated in future fall-risk research and rehabilitation utilizing real-world activity monitoring.

7.
Sci Data ; 5: 180184, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30251996

RESUMO

Mycothiol (MSH) and ergothioneine (ERG) are thiols able to compensate for each other to protect mycobacteria against oxidative stress. Gamma-glutamylcysteine (GGC), another thiol and an intermediate in ERG biosynthesis has detoxification abilities. Five enzymes are involved in ERG biosynthesis, namely EgtA, EgtB, EgtC, EgtD and EgtE. The role of these enzymes in the production of ERG had been unclear. On the other hand, the enzyme MshA is known to be essential for MSH biosynthesis. In this manuscript, we describe the raw data of the generation and characterization of Mycobacterium tuberculosis (M.tb) mutants harbouring a deletion of the gene coding for each of these enzymes, and the raw data of the phenotypic characterization of the obtained thiol-deficient M.tb mutants. High throughput screening (HTS) of off-patent drugs and natural compounds revealed few compounds that displayed a higher activity against the thiol-deficient mutants relative to the wild-type strain. The mode of action of these drugs was further investigated. Raw data displaying these results are described here.


Assuntos
Cisteína/deficiência , Cisteína/genética , Dipeptídeos/deficiência , Dipeptídeos/genética , Ergotioneína/deficiência , Ergotioneína/genética , Glicopeptídeos/deficiência , Glicopeptídeos/genética , Inositol/deficiência , Inositol/genética , Mycobacterium tuberculosis , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Mutação , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Estresse Oxidativo/genética , Compostos de Sulfidrila
8.
Neuroradiology ; 60(10): 1063-1073, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30105622

RESUMO

PURPOSE: Brain metabolites show very rapid maturation over infancy, particularly following very preterm (VPT) birth, and can provide an index of brain injury. The utility of magnetic resonance imaging (MRS, magnetic resonance spectroscopy) in predicting outcome in VPT-born infants is largely limited to 2-year outcomes. We examined the value of MRS in VPT followed longitudinally to 4 years. METHODS: MRS datasets were acquired in 45 VPT infants (< 32 weeks gestational age) longitudinally: at birth, at term-equivalent and at 4 years of age. Using LCModel analyses in a basal ganglia voxel, we investigated metabolite ratios as a function of age, brain injury and outcome. We also studied a full-term (FT) cohort at 4 years and compared group differences with outcome. RESULTS: We found significant age-related changes in many brain metabolites in infancy, including phosphocreatine (CR)/phosphocholine (CHO), N-acetylaspartylglutamate (NAA)/CHO, myoinositol (INS)/CHO and INS/CR; there were no significant MRS differences between VPT and FT groups at 4 years of age, or differences at 4 years as a function of early brain injury or outcome. The rate of change in metabolite ratios from VPT birth to term-equivalent age did not predict outcome in the VPT children at 4 years. CONCLUSION: Brain metabolite ratios measured in VPT-born infants have shown associations with short-term outcomes, but these correlations did not extend to early childhood nor predict cognitive sequelae. The most frequently reported poor outcome in VPT-born children is cognitive difficulties starting at early school age. MRS metrics early in the infant's life do not appear to predict these longer-term outcomes.


Assuntos
Encéfalo/metabolismo , Lactente Extremamente Prematuro , Espectroscopia de Ressonância Magnética/métodos , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Pré-Escolar , Colina/metabolismo , Creatina/metabolismo , Feminino , Humanos , Recém-Nascido , Inositol/metabolismo , Estudos Longitudinais , Masculino
9.
Phys Rev Lett ; 121(2): 022502, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30085703

RESUMO

Lifetimes of the first excited 2^{+} and 4^{+} states in the extremely neutron-deficient nuclide ^{172}Pt have been measured for the first time using the recoil-distance Doppler shift and recoil-decay tagging techniques. An unusually low value of the ratio B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+})=0.55(19) was found, similar to a handful of other such anomalous cases observed in the entire Segré chart. The observation adds to a cluster of a few extremely neutron-deficient nuclides of the heavy transition metals with neutron numbers N≈90-94 featuring the effect. No theoretical model calculations reported to date have been able to explain the anomalously low B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+}) ratios observed in these cases. Such low values cannot, e.g., be explained within the framework of the geometrical collective model or by algebraic approaches within the interacting boson model framework. It is proposed that the group of B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+}) ratios in the extremely neutron-deficient even-even W, Os, and Pt nuclei around neutron numbers N≈90-94 reveal a quantum phase transition from a seniority-conserving structure to a collective regime as a function of neutron number. Although a system governed by seniority symmetry is the only theoretical framework for which such an effect may naturally occur, the phenomenon is highly unexpected for these nuclei that are not situated near closed shells.

10.
Hum Genet ; 137(8): 637-645, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30074075

RESUMO

In the United Kingdom (UK), transfer of genomic data to third countries is regulated by data protection legislation. This is a composite of domestic and European Union (EU) law, with EU law to be adopted as domestic law when Brexit takes place. In this paper we consider the content of data protection legislation and the likely impact of Brexit on transfers of genomic data from the UK to other countries. We examine the advice by regulators not to rely upon consent as a lawful basis for processing under data protection law, at least not when personal data are used for research purposes, and consider some of the other ways in which the research context can qualify an individual's ability to exercise control over processing operations. We explain how the process of pseudonymization is to be understood in the context of transfer of genomic data to third parties, as well as how adequacy of data protection in a third country is to be determined in general terms. We conclude with reflections on the future direction of UK data protection law post Brexit with the reclassification of the UK itself as a third country.


Assuntos
Bases de Dados Genéticas , Privacidade Genética , Pesquisa em Genética/legislação & jurisprudência , Disseminação de Informação/legislação & jurisprudência , Informações Pessoalmente Identificáveis , Bases de Dados Genéticas/legislação & jurisprudência , Bases de Dados Genéticas/normas , Privacidade Genética/legislação & jurisprudência , Privacidade Genética/normas , Humanos , Informações Pessoalmente Identificáveis/legislação & jurisprudência , Informações Pessoalmente Identificáveis/normas , Reino Unido
11.
J Environ Manage ; 224: 69-76, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30031920

RESUMO

Flood Risk Management (FRM) is often essential to reduce the risk of flooding to properties and infrastructure in urban landscapes, but typically degrades the habitats required by many aquatic animals for foraging, refuge and reproduction. This conflict between flood risk management and biodiversity is driven by conflicting directives, such as the EU Floods and Water Framework Directives, and has led to a requirement for synergistic solutions for FRM that integrate river restoration actions. Unfortunately, ecological monitoring and appraisal of combined FRM and river restoration works is inadequate. This paper uses a case study from the River Don in Northern England to evaluate the effects of the FRM and subsequent river restoration works on instream habitat and the associated fish assemblage over an 8-year period. Flood risk management created a homogeneous channel but did not negatively affect fish species composition or densities, specifically brown trout. Densities of adult brown trout were comparable pre and post-FRM, while densities of juvenile bullhead and brown trout increased dramatically post FRM. River restoration works created a heterogeneous channel but did not significantly improve species composition or brown trout density. Species composition post-river restoration works returned to that similar to pre-FRM over a short-term period, but with improved numbers of juvenile bullhead. Although habitat complexity increased after river restoration works, long-term changes in species composition and densities were marginal, probably because the river reset habitat complexity within the time framework of the study.


Assuntos
Inundações , Gestão de Riscos , Animais , Ecossistema , Inglaterra , Peixes , Rios
12.
Phys Med ; 45 Suppl 1: S2, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29413850

RESUMO

In proton beam therapy precise knowledge of the proton beam range is essential to guarantee the treatment's efficacy and to avoid unnecessary toxicities. Unlike photon beams, protons stop inside the patient's body, therefore a direct detection of the distal fall-off is impossible. One technique to determine the beam range is to detect the prompt gamma (PG) rays emitted from the nuclei de-exciting following proton bombardment [1]. PG emission is almost instantaneous and has a high-production rate. The aim of this project is to develop a new method, based on an optimized PG detector system, which can achieve 3D range determination with an uncertainty of no more than 2 mm. The presented method is based on the detection of discrete gamma-rays. As a first step, the position reconstruction capability of the PG detector system was examined by means of Geant4 simulations. The prototype system is comprised of 12 LaBr3(Ce) detectors. The information recorded by each individual detector is fed into a reconstruction algorithm to determine the gamma-ray emission point in 3 dimensions. The development of the algorithm, proof-of-principle and simulation validation, have all been conducted using a sealed 60Co source. Our simulations demonstrate that an ideal detector system with the current reconstruction algorithm is capable of determining the source position with sub-millimetre accuracy. Having obtained proof-of-principle for the reconstruction algorithm the next stage is to investigate how implementing a realistic detector system affects the reconstruction performance. In addition, the ability of the detector system to discriminate between multiple sources in different positions is under evaluation.

13.
Int J Dev Neurosci ; 66: 54-62, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29413879

RESUMO

Measurement of laterality of motor cortical activations may provide valuable information about lower limb control in children with unilateral cerebral palsy (UCP). Evidence from upper limb research suggests that increased contralateral activity may accompany functional gains. However, lower limb areas of activation and associated changes have been underexplored due to challenges with imaging motor cortical leg representations. In this study, methods for a task-based functional magnetic resonance imaging (fMRI) ankle dorsiflexion paradigm were refined with three pilot groups of participants: (i) adults (n = 5); (ii) typically developing (TD) children (n = 5) and; (iii) children with UCP (n = 4). Parameters of experimental design, task resistance, reproducibility, and pre-scan procedures were tested/refined using a staged development approach with additions or changes introduced if image quality did not meet pre-defined standards. When image quality was acceptable for two consecutive participants, the next participant group was recruited to test/refine the next parameter. The final paradigm involved an event-related design of a single dorsiflexion movement against individualized resistance, with two runs per leg. It included a pre-scan session to increase child comfort and determine task resistance. This paradigm produced valid data for laterality index (LI) calculations to determine the ratio of activity in each hemisphere. Ventricle and lesion masks were used in non-linear image registration, and individual thresholds were used for extent-based LI calculations. LI of dominant ankle movements were contralateral (LI ≥ +0.2) for TD children (mean LI = +0.89, std = 0.27) and children with UCP (mean LI = +0.86, std = 0.26). For the affected ankle of children with UCP, LI values indicated ipsilateral and/or contralateral activation (mean LI = +0.02, std = 0.71, range -0.92 to +1.00). This fMRI paradigm will support investigations of cortical activation and mechanisms of skill improvement following lower limb interventions.


Assuntos
Tornozelo/inervação , Córtex Cerebral/diagnóstico por imagem , Paralisia Cerebral/diagnóstico por imagem , Lateralidade Funcional/fisiologia , Imageamento por Ressonância Magnética , Movimento/fisiologia , Adulto , Fatores Etários , Paralisia Cerebral/fisiopatologia , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Oxigênio/sangue , Reflexo/fisiologia
14.
Biochem Biophys Res Commun ; 495(1): 174-178, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29101028

RESUMO

Mycobacterium tuberculosis (M.tb.), the causative agent of tuberculosis (TB), cannot synthesize GSH, but synthesizes two major low molecular weight thiols namely mycothiol (MSH) and ergothioneine (ERG). Gamma-glutamylcysteine (GGC), an intermediate in GSH synthesis, has been implicated in the protection of lactic acid bacteria from oxidative stress in the absence of GSH. In mycobacteria, GGC is an intermediate in ERG biosynthesis, and its formation is catalysed by EgtA (GshA). GGC is subsequently used by EgtB in the formation of hercynine-sulphoxide-GGC. In this study, M.tb. mutants harbouring unmarked, in-frame deletions in each of the fives genes involved in ERG biosynthesis (egtA, egtB, egtC, egtD and egtE) or a marked deletion of the mshA gene (required for MSH biosynthesis) were generated. Liquid chromatography tandem mass spectrometry analyses (LC-MS) revealed that the production of GGC was elevated in the MSH-deficient and the ERG-deficient mutants. The ERG-deficient ΔegtB mutant which accumulated GGC was more resistant to oxidative and nitrosative stress than the ERG-deficient, GGC-deficient ΔegtA mutant. This implicates GGC in the detoxification of reactive oxygen and nitrogen species in M.tb.


Assuntos
Dipeptídeos/metabolismo , Ergotioneína/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Estresse Nitrosativo , Estresse Oxidativo , Vias Biossintéticas , Cisteína/genética , Cisteína/metabolismo , Dipeptídeos/genética , Ergotioneína/metabolismo , Deleção de Genes , Glicopeptídeos/genética , Glicopeptídeos/metabolismo , Humanos , Inositol/genética , Inositol/metabolismo , Tuberculose/microbiologia
15.
J Appl Microbiol ; 122(5): 1389-1401, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28258625

RESUMO

AIMS: To identify production and processing practices that might reduce Campylobacter numbers contaminating chicken broiler carcasses. METHODS AND RESULTS: The numbers of campylobacters were determined on carcass neck skins after processing or in broiler house litter samples. Supplementary information that described farm layouts, farming conditions for individual flocks, the slaughterhouse layouts and operating conditions inside plants was collected, matched with each Campylobacter test result. Statistical models predicting the numbers of campylobacters on neck skins and in litter were constructed. Carcass microbial contamination was more strongly influenced by on-farm production practices compared with slaughterhouse activities. We observed correlations between the chilling, washing and defeathering stages of processing and the numbers of campylobacters on carcasses. There were factors on farm that also correlated with numbers of campylobacters in litter. These included bird gender, the exclusion of dogs from houses, beetle presence in the house litter and the materials used to construct the house frame. CONCLUSIONS: Changes in farming practices have greater potential for reducing chicken carcass microbial contamination compared with processing interventions. SIGNIFICANCE AND IMPACT OF THE STUDY: Routine commercial practices were identified that were correlated with lowered numbers of campylobacters. Consequently, these practices are likely to be both cost-effective and suitable for adoption into established farms and commercial processing.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter/isolamento & purificação , Contaminação de Alimentos/análise , Carne/microbiologia , Doenças das Aves Domésticas/microbiologia , Matadouros/normas , Animais , Campylobacter/classificação , Campylobacter/genética , Infecções por Campylobacter/microbiologia , Galinhas , Contagem de Colônia Microbiana , Cães , Microbiologia de Alimentos
16.
Int J Obes (Lond) ; 41(5): 824-827, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28127042

RESUMO

Childhood obesity is a major public health concern; behavioural interventions induce weight reduction in some, but success is variable. Heart rate variability (HRV) has been associated with impulse control and extent of dieting success. This study investigated the relationship between HRV and post childhood obesity intervention weight-management success, and involved recording the frequency-domain HRV measures ratio between low frequency and high frequency power (LF/HF) and high frequency power (HF), and the time-domain measure, percentage of successive beat-to-beat intervals that differ by more than 50ms (PNN50). It was expected that greater LF/HF and lower HF would be associated with greater post-intervention weight gain, and that greater PNN50 would be associated with greater impulse control. Seventy-four participants aged 9-14 (M=10.7; s.d.: 1.1) attended a weight-management camp, where HRV was recorded. Stop signal reaction time (SSRT) was also recorded as a measure of impulse control. As expected, SSRT was positively associated with pre-intervention body mass (r=0.301, P=0.010) and negatively associated with PNN50 (ß=0.29, P=0.031). Post-intervention body mass change was positively associated with LF/HF (ß=0.34, P=0.037), but was not associated with HF. Lifestyle interventions may have a greater chance of effectively supporting long-term weight-management for children with lower LF/HF; assessing HRV of obese children may be helpful in informing obesity treatment decisions.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Pressão Sanguínea/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Frequência Cardíaca/fisiologia , Obesidade Infantil/prevenção & controle , Obesidade Infantil/fisiopatologia , Programas de Redução de Peso , Adolescente , Índice de Massa Corporal , Criança , Feminino , Seguimentos , Humanos , Masculino , Obesidade Infantil/complicações , Valor Preditivo dos Testes , Avaliação de Programas e Projetos de Saúde , Catar , Resultado do Tratamento
17.
BMC Neurosci ; 17: 13, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27029195

RESUMO

BACKGROUND: Posttraumatic stress disorder (PTSD), an anxiety disorder that can develop after exposure to psychological trauma, impacts up to 20 % of soldiers returning from combat-related deployment. Advanced neuroimaging holds diagnostic and prognostic potential for furthering our understanding of its etiology. Previous imaging studies on combat-related PTSD have focused on selected structures, such as the hippocampi and cortex, but none conducted a comprehensive examination of both the cerebrum and cerebellum. The present study provides a complete analysis of cortical, subcortical, and cerebellar anatomy in a single cohort. Forty-seven magnetic resonance images (MRIs) were collected from 24 soldiers with PTSD and 23 Control soldiers. Each image was segmented into 78 cortical brain regions and 81,924 vertices using the corticometric iterative vertex based estimation of thickness algorithm, allowing for both a region-based and a vertex-based cortical analysis, respectively. Subcortical volumetric analyses of the hippocampi, cerebellum, thalamus, globus pallidus, caudate, putamen, and many sub-regions were conducted following their segmentation using Multiple Automatically Generated Templates Brain algorithm. RESULTS: Participants with PTSD were found to have reduced cortical thickness, primarily in the frontal and temporal lobes, with no preference for laterality. The region-based analyses further revealed localized thinning as well as thickening in several sub-regions. These results were accompanied by decreased volumes of the caudate and right hippocampus, as computed relative to total cerebral volume. Enlargement in several cerebellar lobules (relative to total cerebellar volume) was also observed in the PTSD group. CONCLUSIONS: These data highlight the distributed structural differences between soldiers with and without PTSD, and emphasize the diagnostic potential of high-resolution MRI.


Assuntos
Encéfalo/patologia , Militares/psicologia , Transtornos de Estresse Pós-Traumáticos/patologia , Adulto , Humanos , Inteligência , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
18.
Hum Mov Sci ; 47: 116-120, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26974038

RESUMO

Turning bias, the preferential tendency to turn toward a given direction has been reported in both rodents and human participants. The observational gait method of determining turning bias in humans requires a stop prior to turning. This study removed the stop and hypothesised that turning bias would remain the same between stop and non-stop conditions if bias was solely under the control of neurochemical asymmetries. The results showed that statistically turning bias remained the same (to the left) regardless of method used but there was no agreement between the methods thus rejecting the hypothesis. It is likely that when not stopping biomechanical factors related to gait when turning influence the direction of turn rather than solely neurochemical asymmetries.


Assuntos
Lateralidade Funcional/fisiologia , Marcha/fisiologia , Caminhada/fisiologia , Adolescente , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Adulto Jovem
19.
J Autism Dev Disord ; 46(6): 2138-2147, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26899725

RESUMO

Diffusion tensor imaging studies show white matter (WM) abnormalities in children with autism spectrum disorder (ASD). However, investigations are often limited by small samples, particularly problematic given the heterogeneity of ASD. We explored WM using DTI in a large sample of 130 children and adolescents (7-15 years) with and without ASD, whether age-related changes differed between ASD and control groups, and the relation between DTI measures and ASD symptomatology. Reduced fractional anisotropy and axial diffusivity were observed in ASD in numerous WM tracts, including the corpus callosum and thalamocortical fibres-tracts crucial for interhemispheric connectivity and higher order information processing. Widespread WM compromise in ASD is consistent with the view that ASD is a disorder of generalized complex information processing.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adolescente , Anisotropia , Encéfalo/diagnóstico por imagem , Criança , Corpo Caloso/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino
20.
Int J Obes (Lond) ; 40(1): 34-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26443341

RESUMO

BACKGROUND/OBJECTIVES: According to the COM-B ('Capability', 'Opportunity', 'Motivation' and 'Behaviour') model of behaviour, three factors are essential for behaviour to occur: capability, opportunity and motivation. Obese children are less likely to feel capable of exercising. The implementation of a new methodological approach to investigate the relationship between perceived exercise capability (PEC) and childhood obesity was conducted, which involved creating a new instrument, and demonstrating how it can be used to measure obesity intervention outcomes. SUBJECTS/METHODS: A questionnaire aiming to measure perceived exercise capability, opportunity and motivation was systematically constructed using the COM-B model and administered to 71 obese children (aged 9-17 years (12.24±0.2.01), body mass index (BMI) standard deviation scores (SDS) 2.80±0.660) at a weight-management camp in northern England. Scale validity and reliability was assessed. Relationships between PEC, as measured by the questionnaire, and BMI SDS were investigated for the children at the weight-management camp, and for 45 Spanish schoolchildren (aged 9-13 years, (10.52±1.23), BMI SDS 0.80±0.99). A pilot study, demonstrating how the questionnaire can be used to measure the effectiveness of an intervention aiming to bring about improved PEC for weight-management camp attendees, was conducted. No participants withdrew from these studies. RESULTS: The questionnaire domain (exercise capability, opportunity and motivation) composite scales were found to have adequate internal consistency (a=0.712-0.796) and construct validity (χ(2)/degrees of freedom=1.55, root mean square error of approximation=0.072, comparative fit index=0.92). Linear regression revealed that low PEC was associated with higher baseline BMI SDS for both UK (b=-0.289, P=0.010) and Spanish (b=-0.446, P=0.047) participants. Pilot study findings provide preliminary evidence for PEC improvements through intervention being achievable, and measurable using the questionnaire. CONCLUSIONS: Evidence is presented for reliability and validity of the questionnaire, and for feasibility of its use in the context of a childhood obesity intervention. Future research could investigate the link between PEC and childhood obesity further.


Assuntos
Tolerância ao Exercício/fisiologia , Exercício Físico/psicologia , Obesidade Infantil/psicologia , Programas de Redução de Peso , Adolescente , Criança , Inglaterra/epidemiologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Motivação , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Projetos Piloto , Reprodutibilidade dos Testes , Autoimagem , Espanha/epidemiologia , Inquéritos e Questionários
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