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1.
Proc Natl Acad Sci U S A ; 119(52): e2210863119, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36534809

RESUMO

Beginning ~3,500 to 3,300 y B.P., humans voyaged into Remote Oceania. Radiocarbon-dated archaeological evidence coupled with cultural, linguistic, and genetic traits indicates two primary migration routes: a Southern Hemisphere and a Northern Hemisphere route. These routes are separated by low-lying, equatorial atolls that were settled during secondary migrations ~1,000 y later after their exposure by relative sea-level fall from a mid-Holocene highstand. High volcanic islands in the Federated States of Micronesia (Pohnpei and Kosrae) also lie between the migration routes and settlement is thought to have occurred during the secondary migrations despite having been above sea level during the initial settlement of Remote Oceania. We reconstruct relative sea level on Pohnpei and Kosrae using radiocarbon-dated mangrove sediment and show that, rather than falling, there was a ~4.3-m rise over the past ~5,700 y. This rise, likely driven by subsidence, implies that evidence for early settlement could lie undiscovered below present sea level. The potential for earlier settlement invites reinterpretation of migration pathways into Remote Oceania and monument building. The UNESCO World Heritage sites of Nan Madol (Pohnpei) and Leluh (Kosrae) were constructed when relative sea level was ~0.94 m (~770 to 750 y B.P.) and ~0.77 m (~640 to 560 y B.P.) lower than present, respectively. Therefore, it is unlikely that they were originally constructed as islets separated by canals filled with ocean water, which is their prevailing interpretation. Due to subsidence, we propose that these islands and monuments are more vulnerable to future relative sea-level rise than previously identified.


Assuntos
Meio Ambiente , Elevação do Nível do Mar , Humanos , Oceania , Micronésia , Arqueologia
2.
Nature ; 564(7736): 400-404, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30568196

RESUMO

Identifying the causes of historical trends in relative sea level-the height of the sea surface relative to Earth's crust-is a prerequisite for predicting future changes. Rates of change along the eastern coast of the USA (the US East Coast) during the past century were spatially variable, and relative sea level rose faster along the Mid-Atlantic Bight than along the South Atlantic Bight and the Gulf of Maine. Past studies suggest that Earth's ongoing response to the last deglaciation1-5, surface redistribution of ice and water5-9 and changes in ocean circulation9-13 contributed considerably to this large-scale spatial pattern. Here we analyse instrumental data14,15 and proxy reconstructions4,12 using probabilistic methods16-18 to show that vertical motions of Earth's crust exerted the dominant control on regional spatial differences in relative sea-level trends along the US East Coast during 1900-2017, explaining most of the large-scale spatial variance. Rates of coastal subsidence caused by ongoing relaxation of the peripheral forebulge associated with the last deglaciation are strongest near North Carolina, Maryland and Virginia. Such structure indicates that Earth's elastic lithosphere is thicker than has been assumed in other models19-22. We also find a substantial coastal gradient in relative sea-level trends over this period that is unrelated to deglaciation and suggests contributions from twentieth-century redistribution of ice and water. Our results indicate that the majority of large-scale spatial variation in long-term rates of relative sea-level rise on the US East Coast is due to geological processes that will persist at similar rates for centuries.

3.
Neuropsychol Rehabil ; : 1-27, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38870482

RESUMO

Acquired Brain Injury (ABI) often results in significant challenges, yet it may also facilitate Post-Traumatic Growth (PTG). This review explores a critical question: "What are the main factors contributing to PTG following ABI, and what potential barriers to its development are perceived by ABI survivors?" Here we aim to systematically uncover these contributors and barriers to PTG through a meta-synthesis, involving a comprehensive review of previously published qualitative research on this topic. A literature search was conducted across PsycINFO, CINAHL, and MEDLINE up to December 2022 to identify studies for inclusion. From an initial pool of 1,946 records, eleven articles were selected for inclusion. Reflexive thematic analysis yielded three analytical themes including "Journey to Self-Rediscovery", "Strength in Connection" and "Overcoming Obstacles". Our findings also revealed facilitators and barriers across multiple levels of scale including personal (e.g., acceptance versus resignation), interpersonal (e.g., positive social ties versus difficulties making social connections), and systemic (e.g., new meaning and purpose versus financial constraints) scales. Our research extends existing knowledge in ABI rehabilitation, providing a more nuanced understanding of the dynamics influencing PTG with implications for clinicians seeking to promote wellbeing following brain injury.

4.
BMC Public Health ; 23(1): 1062, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37277757

RESUMO

BACKGROUND: Adolescent mental health has become a public health concern as 10-20% of adolescents have experiences with mental health problems. Improving mental health education is critical to reducing stigma and improving access to appropriate care when needed. Here we examine the impact of a mental health literacy programme (Guide Cymru) in young adolescents in the UK. A randomised controlled trial assessed the effectiveness of the Guide Cymru intervention. METHOD: A total of 1,926 pupils (860 males and 1066 females) aged 13-14 (year 9) took part in the study. The secondary schools were randomised into the active and control arms of the study. Teachers in the active arm of the study were trained on the Guide Cymru and then delivered the intervention to their pupils. Pupils in the active groups received six modules of mental health literacy (the Guide Cymru), and control schools received teaching as usual. Mental health literacy across several domains (e.g., knowledge, stigma, help-seeking intentions) were assessed both before and after the intervention. Data collection for the randomised controlled trial ran from September 2019 to March 2020. Multi-level modelling analysis was conducted to account for the clustered nature of the design. RESULTS: All aspects of mental health literacy, including mental health knowledge (g = 0.32), good mental health behaviours (g = 0.22), mental health stigmas (g = 0.16), intentions to seek help (g = 0.15), and avoidant coping (g = 0.14) improved after completing the Guide Cymru programme (ps < .001). DISCUSSION: The current study presents evidence for the Guide Cymru's effectiveness in improving secondary school pupils' mental health literacy. We demonstrate that providing teachers with appropriate resources and training to deliver the Guide Cymru programme within their classrooms can improve the mental health literacy of pupils. These findings have important implications for the beneficial impacts the secondary school system can have on reducing the burden of mental health problems at a critical point in a young person's life. TRIAL REGISTRATION: ISRCTN15462041. Registered 03/10/2019.


Assuntos
Letramento em Saúde , Transtornos Mentais , Masculino , Adolescente , Feminino , Humanos , País de Gales , Transtornos Mentais/psicologia , Saúde Mental , Instituições Acadêmicas , Serviços de Saúde Escolar
5.
J Occup Environ Hyg ; 20(10): 468-479, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37540215

RESUMO

COVID-19 has had a devastating impact worldwide, including in care homes where there have been substantial numbers of cases among a very vulnerable population. A key mechanism for managing exposure to the virus and targeting interventions is contact tracing. Unfortunately, environments such as care homes that were most catastrophically impacted by COVID-19 are also those least amenable to traditional contact tracing. A promising alternative to recall and smartphone-based contact tracing approaches is the use of discrete wearable devices that exploit Bluetooth Low Energy (BLE) and Long-Range Wide Area Network (LoRaWAN) technologies. However, the real-world performance of these devices in the context of contact tracing is uncertain. A series of experiments were conducted to evaluate the performance of a wearables system that is based on BLE and LoRaWAN technologies. In each experiment, the number of successful contacts was recorded and the physical distance between two contacts was compared to a calculated distance using the Received Signal Strength Indication (RSSI) to determine the precision, error rate, and duration of proximity. The overall average system contact detection success rate was measured as 75.5%; when wearables were used as per the manufacturer's guidelines the contact detection success rate increased to 81.5%, but when obstructed by everyday objects such as clothing or inside a bag the contact detection success rate was only 64.2%. The calculated distance using RSSI was close to the physical distance in the absence of obstacles. However, in the presence of typical obstacles found in care home settings, the reliability of detection decreased, and the calculated distance usually appeared far from the actual contact point. The results suggest that under real-world conditions there may be a large proportion of contacts that are underestimated or undetected.


Assuntos
COVID-19 , Dispositivos Eletrônicos Vestíveis , Humanos , Busca de Comunicante/métodos , Reprodutibilidade dos Testes , Ambiente Domiciliar , COVID-19/epidemiologia , COVID-19/prevenção & controle
6.
Proc Natl Acad Sci U S A ; 115(30): 7729-7734, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29987009

RESUMO

Identifying physical processes responsible for historical coastal sea-level changes is important for anticipating future impacts. Recent studies sought to understand the drivers of interannual to multidecadal sea-level changes on the United States Atlantic and Gulf coasts. Ocean dynamics, terrestrial water storage, vertical land motion, and melting of land ice were highlighted as important mechanisms of sea-level change along this densely populated coast on these time scales. While known to exert an important control on coastal ocean circulation, variable river discharge has been absent from recent discussions of drivers of sea-level change. We update calculations from the 1970s, comparing annual river-discharge and coastal sea-level data along the Gulf of Maine, Mid-Atlantic Bight, South Atlantic Bight, and Gulf of Mexico during 1910-2017. We show that river-discharge and sea-level changes are significantly correlated ([Formula: see text]), such that sea level rises between 0.01 and 0.08 cm for a 1 [Formula: see text] annual river-discharge increase, depending on region. We formulate a theory that describes the relation between river-discharge and halosteric sea-level changes (i.e., changes in sea level related to salinity) as a function of river discharge, Earth's rotation, and density stratification. This theory correctly predicts the order of observed increment sea-level change per unit river-discharge anomaly, suggesting a causal relation. Our results have implications for remote sensing, climate modeling, interpreting Common Era proxy sea-level reconstructions, and projecting coastal flood risk.

7.
Sensors (Basel) ; 21(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34577411

RESUMO

The use of cloth face coverings and face masks has become widespread in light of the COVID-19 pandemic. This paper presents a method of using low cost wirelessly connected carbon dioxide (CO2) sensors to measure the effects of properly and improperly worn face masks on the concentration distribution of exhaled breath around the face. Four types of face masks are used in two indoor environment scenarios. CO2 as a proxy for exhaled breath is being measured with the Sensirion SCD30 CO2 sensor, and data are being transferred wirelessly to a base station. The exhaled CO2 is measured in four directions at various distances from the head of the subject, and interpolated to create spatial heat maps of CO2 concentration. Statistical analysis using the Friedman's analysis of variance (ANOVA) test is carried out to determine the validity of the null hypotheses (i.e., distribution of the CO2 is same) between different experiment conditions. Results suggest CO2 concentrations vary little with the type of mask used; however, improper use of the face mask results in statistically different CO2 spatial distribution of concentration. The use of low cost sensors with a visual interpolation tool could provide an effective method of demonstrating the importance of proper mask wearing to the public.


Assuntos
COVID-19 , Máscaras , Dióxido de Carbono , Humanos , Pandemias , SARS-CoV-2
8.
BMC Public Health ; 20(1): 727, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32429867

RESUMO

BACKGROUND: Adolescence is a crucial period for developing and maintaining good habits for mental health and well-being. This is important for future mental health, as most mental health problems manifest during adolescence. Mental health literacy is the foundation for mental health prevention, stigma reduction, and increased help-seeking efficacy particularly among adolescents. The mental health literacy programme "The Guide", which was developed in Canada, has shown success in increasing mental health literacy in North American 16-17 year olds. "The Guide Cymru" is an adaptation of The Guide designed for a younger age group (13-14 year olds) and for the Welsh culture and context and is being offered to all state schools in Wales. METHODS: This two-armed cluster randomised control trial (RCT) will evaluate the effectiveness of The Guide Cymru. All 205 secondary schools in Wales will be invited to take part, involving up to 30,000 year 9 pupils. Schools will be randomised to either the immediate implementation of The Guide Cymru or to a wait-list control. The wait-list control will receive The Guide Cymru around 12 weeks later. Measures of mental health literacy (assessed via the Knowledge and Attitudes to Mental Health scale) and mental health problems (via the PedsQL and Strengths and Difficulties Questionnaire) will be taken at baseline (pre-intervention), 12 weeks later (after the active group has received The Guide Cymru), and 24 weeks later (after the wait-list control has received The Guide Cymru). DISCUSSION: The trial aims to evaluate if The Guide Cymru increases mental health literacy, including reduced stigma to others and to the self, and increased levels of good mental health behaviours and help-seeking for mental health problems. TRIAL REGISTRATION: ISRCTN15462041. Registered 03/10/2019.


Assuntos
Letramento em Saúde/métodos , Transtornos Mentais/prevenção & controle , Saúde Mental , Serviços de Saúde Escolar , Adolescente , Análise por Conglomerados , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Instituições Acadêmicas , Autoimagem , Estigma Social , Fatores de Tempo , País de Gales
9.
Front Ecol Environ ; 17(7): 375-382, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31875865

RESUMO

Maintaining the continued flow of benefits from science, as well as societal support for science, requires sustained engagement between the research community and the general public. On the basis of data from an international survey of 1092 participants (634 established researchers and 458 students) in 55 countries and 315 research institutions, we found that institutional recognition of engagement activities is perceived to be undervalued relative to the societal benefit of those activities. Many researchers report that their institutions do not reward engagement activities despite institutions' mission statements promoting such engagement. Furthermore, institutions that actually measure engagement activities do so only to a limited extent. Most researchers are strongly motivated to engage with the public for selfless reasons, which suggests that incentives focused on monetary benefits or career progress may not align with researchers' values. If institutions encourage researchers' engagement activities in a more appropriate way - by moving beyond incentives - they might better achieve their institutional missions and bolster the crucial contributions of researchers to society.

10.
Proc Natl Acad Sci U S A ; 113(11): E1434-41, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26903659

RESUMO

We assess the relationship between temperature and global sea-level (GSL) variability over the Common Era through a statistical metaanalysis of proxy relative sea-level reconstructions and tide-gauge data. GSL rose at 0.1 ± 0.1 mm/y (2σ) over 0-700 CE. A GSL fall of 0.2 ± 0.2 mm/y over 1000-1400 CE is associated with ∼ 0.2 °C global mean cooling. A significant GSL acceleration began in the 19th century and yielded a 20th century rise that is extremely likely (probability [Formula: see text]) faster than during any of the previous 27 centuries. A semiempirical model calibrated against the GSL reconstruction indicates that, in the absence of anthropogenic climate change, it is extremely likely ([Formula: see text]) that 20th century GSL would have risen by less than 51% of the observed [Formula: see text] cm. The new semiempirical model largely reconciles previous differences between semiempirical 21st century GSL projections and the process model-based projections summarized in the Intergovernmental Panel on Climate Change's Fifth Assessment Report.

11.
Hum Brain Mapp ; 39(12): 4743-4754, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30076770

RESUMO

Multiple sclerosis (MS) patients present several alterations related to sensing of bodily signals. However, no specific neurocognitive impairment has yet been proposed as a core deficit underlying such symptoms. We aimed to determine whether MS patients present changes in interoception-that is, the monitoring of autonomic bodily information-a process that might be related to various bodily dysfunctions. We performed two studies in 34 relapsing-remitting, early-stage MS patients and 46 controls matched for gender, age, and education. In Study 1, we evaluated the heartbeat-evoked potential (HEP), a cortical signature of interoception, via a 128-channel EEG system during a heartbeat detection task including an exteroceptive and an interoceptive condition. Then, we obtained whole-brain MRI recordings. In Study 2, participants underwent fMRI recordings during two resting-state conditions: mind wandering and interoception. In Study 1, controls exhibited greater HEP modulation during the interoceptive condition than the exteroceptive one, but no systematic differences between conditions emerged in MS patients. Patients presented atrophy in the left insula, the posterior part of the right insula, and the right anterior cingulate cortex, with abnormal associations between neurophysiological and neuroanatomical patterns. In Study 2, controls showed higher functional connectivity and degree for the interoceptive state compared with mind wandering; however, this pattern was absent in patients, who nonetheless presented greater connectivity and degree than controls during mind wandering. MS patients were characterized by atypical multimodal brain signatures of interoception. This finding opens a new agenda to examine the role of inner-signal monitoring in the body symptomatology of MS.


Assuntos
Córtex Cerebral/fisiopatologia , Conectoma/métodos , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Frequência Cardíaca/fisiologia , Interocepção/fisiologia , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Adulto , Atrofia/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/patologia
12.
Rheumatology (Oxford) ; 57(2): 345-353, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121248

RESUMO

Objectives: To characterize 18F-fluorodeoxyglucose (18F-FDG) uptake on whole-body PET/CT in PMR, and identify its precise anatomic correlate using MRI. Methods: Patients with newly diagnosed PMR according to the 2012 EULAR/ACR classification criteria were prospectively recruited. Participants with GCA were excluded. A whole-body 18F-FDG PET/CT scan was performed in all untreated patients. Qualitative and semiquantitative [standardized uptake value maximum (SUVmax)] scoring of abnormal 18F-FDG uptake was undertaken. MRI of the pelvis, knee and wrist and hand was performed in three representative patients with anatomical correlation of FDG-avid sites carried out using Medview fusion software. Results: Twenty-two patients with PMR were recruited. Their mean age was 68.3 years (s.d. 6.3) and 13/22 were male. On whole-body PET/CT, 18F-FDG uptake adjacent to the ischial tuberosities was observed in 21 participants (95.4%) and recorded the highest mean SUVmax value [3.6 (s.d. 1.7)]. A high frequency of posteromedial knee (61.9%) and wrist and/or hand involvement (66.7%) was also appreciated. MRI of the pelvis revealed high T2 signal surrounding the proximal hamstring tendon origins of both semimembranosus and the conjoint tendon of the semitendinosus and biceps femoris. At the knee, peritendonitis at the distal insertion of the semimembranosus was observed. PET/MRI fusion at the pelvis and knee confirmed semimembranosus peritendonitis as the anatomical correlate of 18F-FDG uptake adjacent to the ischial tuberosities and of posteromedial knee structures. Conclusion: Hamstring peritendonitis is a common and distinctive manifestation of PMR on whole-body PET/CT. Trial registration: Australian New Zealand Clinical Trials Registry, http://www.anzctr.org.au, ACTRN1261400696695.


Assuntos
Fluordesoxiglucose F18 , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Polimialgia Reumática/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos , Tendinopatia/diagnóstico por imagem , Idoso , Feminino , Tendões dos Músculos Isquiotibiais/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Polimialgia Reumática/complicações , Estudos Prospectivos , Tendinopatia/etiologia , Imagem Corporal Total/métodos
13.
Proc Natl Acad Sci U S A ; 112(41): 12610-5, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26417111

RESUMO

In a changing climate, future inundation of the United States' Atlantic coast will depend on both storm surges during tropical cyclones and the rising relative sea levels on which those surges occur. However, the observational record of tropical cyclones in the North Atlantic basin is too short (A.D. 1851 to present) to accurately assess long-term trends in storm activity. To overcome this limitation, we use proxy sea level records, and downscale three CMIP5 models to generate large synthetic tropical cyclone data sets for the North Atlantic basin; driving climate conditions span from A.D. 850 to A.D. 2005. We compare pre-anthropogenic era (A.D. 850-1800) and anthropogenic era (A.D.1970-2005) storm surge model results for New York City, exposing links between increased rates of sea level rise and storm flood heights. We find that mean flood heights increased by ∼1.24 m (due mainly to sea level rise) from ∼A.D. 850 to the anthropogenic era, a result that is significant at the 99% confidence level. Additionally, changes in tropical cyclone characteristics have led to increases in the extremes of the types of storms that create the largest storm surges for New York City. As a result, flood risk has greatly increased for the region; for example, the 500-y return period for a ∼2.25-m flood height during the pre-anthropogenic era has decreased to ∼24.4 y in the anthropogenic era. Our results indicate the impacts of climate change on coastal inundation, and call for advanced risk management strategies.


Assuntos
Mudança Climática , Tempestades Ciclônicas , Desastres , Inundações , Modelos Teóricos , Cidade de Nova Iorque
14.
Glob Chang Biol ; 23(2): 755-766, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27343840

RESUMO

To thrive in a time of rapid sea-level rise, tidal marshes will need to migrate upslope into adjacent uplands. Yet little is known about the mechanics of this process, especially in urbanized estuaries, where the adjacent upland is likely to be a mowed lawn rather than a wooded natural area. We studied marsh migration in a Long Island Sound salt marsh using detailed hydrologic, edaphic, and biotic sampling along marsh-to-upland transects in both wooded and lawn environments. We found that the overall pace of marsh development was largely unaffected by whether the upland being invaded was lawn or wooded, but the marsh-edge plant communities that developed in these two environments were quite different, and some indicators (soil salinity, foraminifera) appeared to migrate more easily into lawns. In addition, we found that different aspects of marsh structure and function migrated at different rates: Wetland vegetation appeared to be a leading indicator of marsh migration, while soil characteristics such as redox potential and surface salinity developed later in the process. We defined a 'hydrologic migration zone', consisting of elevations that experience tidal inundation with frequencies ranging from 20% to 0.5% of high tides. This hydrologically defined zone - which extended to an elevation higher than the highest astronomical tide datum - captured the biotic and edaphic marsh-upland ecotone. Tidal inundation at the upper border of this migration zone is highly variable over time and may be rising more rapidly than mean sea level. Our results indicate that land management practices at the upland periphery of tidal marshes can facilitate or impede ecosystem migration in response to rising sea level. These findings are applicable to large areas of tidal marsh along the U.S. Atlantic coast and in other urbanized coastal settings.


Assuntos
Solo/química , Áreas Alagadas , Ecossistema , Estuários , Salinidade
15.
J Comput Assist Tomogr ; 41(6): 854-860, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28708731

RESUMO

OBJECTIVE: The purpose of this study is to evaluate feasibility, image quality (IQ), and accuracy of noncontrast hybrid arterial spin labeling (NoHASL) magnetic resonance angiography (MRA) compared with time of flight (TOF) MRA and contrast-enhanced (CE) MRA in patients with known/suspected cerebrovascular ischemia. METHODS: Thirty inpatients were imaged at 1.5 T. Two neuroradiologists assessed 630 intracranial arterial segments for IQ (1, nondiagnostic; 3, satisfactory for diagnosis; and 5, excellent). Hemodynamically significant stenosis (>50%) was assessed against all combined techniques as reference. RESULTS: The NoHASL MRA IQ was diagnostic (3.32 ± 0.86) but affected by signal to noise ratio and spatial resolution limitations and significantly inferior to TOF (3.48 ± 0.68) and CE MRA (3.44 ± 0.78) (P < 0.0001 in both comparisons). Fourteen (2.2%) of 630 segments had hemodynamically significant stenoses at the reference standard. Sensitivity/specificity was not significantly different between techniques: NoHASL MRA, 67.9%/90.0%; TOF MRA, 67.9%/97.7%; and CE MRA, 50.0%/98.7%. CONCLUSIONS: The NoHASL MRA is feasible, with diagnostic quality imaging of proximal intracranial vessels. Low disease prevalence limited the assessment of technique accuracy.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Neuroimagem/métodos , Marcadores de Spin , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
16.
J Paediatr Child Health ; 53(10): 942-949, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28749577

RESUMO

AIM: The aim of this study was to describe antibiotic exposure in Australian infants during the first year of life, focusing on antibiotic class, indication, risk factors associated with exposure and comparison with international counterparts. METHODS: The Barwon Infant Study is a birth cohort study (n = 1074) with an unselected antenatal sampling frame from a large regional centre in Victoria, Australia. Longitudinal data on infection and medication were collected at 1, 3, 6, 9 and 12 months by parental questionnaire and from general practitioner and hospital records. Predictors of questionnaire non-completion were identified. A total of 660 infants with complete serial data were comprehensively examined. Antibiotic exposure was calculated as (i) antibiotic prescriptions and (ii) antibiotic days-exposed per person-year. RESULTS: Mean antibiotic prescription rate was 0.92 prescriptions (95% confidence interval (CI), 0.83-1.02) per person-year, with the highest rates in those aged <1 month (1.50 (95% CI, 1.09-1.91) per person-year). A total of 50.0% of infants were exposed to at least one antibiotic in their first year of life. Increasing number of siblings was associated with increased antibiotic exposure. Penicillin with extended spectrum (365 of 661 antibiotic prescriptions, 52.6%) and cephalosporins (12.0%) were the most frequently prescribed antibiotics. One fifth of antibiotics were prescribed for respiratory tract infections and bronchiolitis. CONCLUSION: Australian infants in this large population-based study are exposed to considerably more antibiotics than the majority of their international counterparts. Interventions aimed at addressing avoidable prescribing by medical practitioners and modifiable risk factors associated with antibiotic exposure may reduce antibiotic use.


Assuntos
Antibacterianos/uso terapêutico , Uso de Medicamentos , Adulto , Estudos de Coortes , Prescrições de Medicamentos/estatística & dados numéricos , Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Lactente , Masculino , Prevalência , Infecções Respiratórias/tratamento farmacológico , Inquéritos e Questionários , Vitória , Adulto Jovem
17.
Psychosom Med ; 78(8): 950-958, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27359180

RESUMO

OBJECTIVES: African Americans are characterized by higher heart rate variability (HRV), a finding ostensibly associated with beneficial health outcomes. However, these findings are at odds with other evidence that blacks have worse cardiovascular outcomes. Here, we examine associations in a large cohort from the ELSA-Brasil study and determined whether these effects are mediated by discrimination. METHODS: Three groups were compared on the basis of self-declared race: "black" (n = 2,020), "brown" (n = 3,502), and "white" (n = 6,467). Perceived discrimination was measured using a modified version of the Everyday Discrimination Scale. Resting-state HRV was extracted from 10-minute resting-state electrocardiograms. Racial differences in HRV were determined by regression analyses weighted by propensity scores, which controlled for potentially confounding variables including age, sex, education, and other health-related information. Nonlinear mediation analysis quantified the average total effect, comprising direct (race-HRV) and indirect (race-discrimination-HRV) pathways. RESULTS: Black participants displayed higher HRV relative to brown (Cohen's d = 0.20) and white participants (Cohen's d = 0.31). Brown relative to white participants also displayed a small but significantly higher HRV (Cohen's d = 0.14). Discrimination indirectly contributed to the effects of race on HRV. CONCLUSIONS: This large cohort from the Brazilian population shows that HRV is greatest in black, followed by brown, relative to white participants. The presence of higher HRV in these groups may reflect a sustained compensatory psychophysiological response to the adverse effects of discrimination. Additional research is needed to determine the health consequences of these differences in HRV across racial and ethnic groups.


Assuntos
Empregados do Governo/estatística & dados numéricos , Frequência Cardíaca/fisiologia , Grupos Raciais/estatística & dados numéricos , Racismo/estatística & dados numéricos , Adulto , Idoso , População Negra/estatística & dados numéricos , Brasil/etnologia , Humanos , Pessoa de Meia-Idade , Racismo/etnologia , População Branca/estatística & dados numéricos
18.
Psychosom Med ; 78(7): 810-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27219492

RESUMO

OBJECTIVE: Debate has focused on the effects of the selective serotonin reuptake inhibitor (SSRI) antidepressants on heart rate (HR) and HR variability (HRV), both of which are predictors of adverse cardiovascular events. Here, we examine the associations between specific SSRI antidepressants and resting state HR (and HRV) after accounting for a host of potential confounding factors using propensity score techniques. METHODS: Participants included 10,466 not taking antidepressants, 46 participants taking escitalopram, 86 taking citalopram, 66 taking fluoxetine, 103 taking paroxetine, and 139 taking sertraline. HR and HRV (root mean square of successive squared differences, high frequency) were extracted from 10-minute resting-state ECGs. Analyses including propensity score weighting and matching were conducted using R-statistics to control for potentially confounding variables. RESULTS: Major findings indicated that users of all SSRI medications-except fluoxetine-displayed lower HRV relative to nonusers. Users of paroxetine also displayed significantly lower HRV relative to users of citalopram (Cohen's d = 0.42), fluoxetine (Cohen's d = 0.54), and sertraline (Cohen's d = 0.35), but not escitalopram. Although associations were also observed for HR, these were less robust than those for HRV. CONCLUSIONS: Although paroxetine is associated with decreases in HRV relative to nonusers, as well as users of other SSRI medications, fluoxetine was the only medication not to display significant alterations in HR or HRV. These conclusions are limited by the cross-sectional design and nonrandomized nature of medication prescriptions. Findings highlight the importance of focusing on specific medications, rather than more heterogeneous groupings according to antidepressant action, and may have implications for health and well-being for the longer term.


Assuntos
Citalopram/efeitos adversos , Eletrocardiografia/efeitos dos fármacos , Fluoxetina/efeitos adversos , Frequência Cardíaca/efeitos dos fármacos , Paroxetina/efeitos adversos , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Sertralina/efeitos adversos , Adulto , Idoso , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Cephalalgia ; 36(3): 265-78, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25962595

RESUMO

OBJECTIVE: Vagal nerve activity-indexed by heart rate variability (HRV)-has been linked to altered pain processing and inflammation, both of which may underpin headache disorders and lead to cardiovascular disease (CVD). Here we examined the evidence for differences in parasympathetic (vagal) activity indexed by time- and frequency-domain measures of HRV in patients with headache disorders compared to healthy controls (HCs). METHODS: A systematic review and meta-analysis was conducted on studies investigating group differences in vagally mediated HRV (vmHRV) including time- (root-mean-square of successive R-R-interval differences (RMSSD)) and frequency- (high-frequency HRV) domain measures. Studies eligible for inclusion were identified by a systematic search of the literature, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. RESULTS: Seven studies reporting a total of 10 comparisons of patients with headache disorders (HF-HRV n = 67, RMSSD n = 122) and HCs (HF-HRV n = 64, RMSSD n = 125) were eligible for inclusion. Random-effects meta-analysis revealed a significant main effect on RMSSD (Z = 2.03, p = 0.04; Hedges' g = -0.63; 95% CI (-1.24, -0.02); k = 6) and similar pooled effect size estimates for HF-HRV when breathing was controlled (g = -0.30; 95% CI (-0.69; 0.10)) but not when breathing was not controlled (g = 0.02; 95% CI (-0.69; 0.74)). Controlling for breathing had no effect on RMSSD. CONCLUSION: vmHRV is reduced in patients with headache disorders, findings associated with a medium effect size. Suggestions for future research in this area are provided, emphasizing a need to investigate the impact of headache disorders and commonly comorbid conditions-including mental disorders-as well as the investigation of the risk for CVD in migraine in particular. We further emphasize the need for large-scale studies to investigate HRV as a mechanism mediating the association of migraine and CVD.


Assuntos
Cefaleia/fisiopatologia , Frequência Cardíaca/fisiologia , Nervo Vago/fisiologia , Humanos
20.
BMC Psychiatry ; 16: 133, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27165346

RESUMO

BACKGROUND: Cumulative exposure to potentially traumatic events (PTEs) increases risk for mental distress in conflict-affected settings, but the psychophysiological mechanisms that mediate this dose-response relationship are unknown. We investigated diminished heart rate variability (HRV) - an index of vagus nerve function and a robust predictor of emotion regulation capacity - as a vulnerability marker that potentially mediates the association between PTE exposure, age and symptoms of posttraumatic stress disorder (PTSD), psychological distress and aggressive behavior, in a community sample from Timor-Leste - a post-conflict country with a history of mass violence. METHOD: Resting state heart rate data was recorded from 45 cases of PTSD, depression and intermittent explosive disorder (IED); and 29 non-case controls. RESULTS: Resting HRV was significantly reduced in the combined case group compared with non-cases (p = .021; Cohen's d = 0.5). A significant mediation effect was also observed, whereby a sequence of increased age, reduced HRV and elevated PTSD symptoms mediated the association between PTE exposure and distress (B = .06, SE = .05, 95% CI = [.00-.217]) and aggression (B = .02, SE = .02, 95% CI = [.0003-.069])). CONCLUSION: The findings demonstrate an association between diminished resting HRV and psychopathology. Moreover, age-related HRV reductions emerged as a potential psychophysiological mechanism that underlies enhanced vulnerability to distress and aggression following cumulative PTE exposure.


Assuntos
Conflito Psicológico , Frequência Cardíaca/fisiologia , Transtornos Mentais/fisiopatologia , Estresse Psicológico/fisiopatologia , Violência/estatística & dados numéricos , Adulto , Fatores Etários , Idoso , Agressão/fisiologia , Agressão/psicologia , Feminino , Humanos , Masculino , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia , Timor-Leste/epidemiologia , Violência/psicologia , Adulto Jovem
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