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1.
Front Pharmacol ; 14: 1223808, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663267

RESUMO

Introduction: ß-chloroprene (2-chloro-1,3-butadiene; CP) causes lung tumors after inhalation exposures in rats and mice. Mice develop these tumors at lower exposures than rats. In rats CP exposures cause depletion of lung glutathione (GSH). Methods: PBPK models developed to relate the appearance of mouse lung tumors with rates of CP metabolism to reactive metabolites or total amounts metabolized during exposures have been expanded to include production of reactive metabolites from CP. The extended PBPK model describes both the unstable oxirane metabolite, 2-CEO, and metabolism of the more stable oxirane, 1-CEO, to reactive metabolites via microsomal oxidation to a diepoxide, and linked production of these metabolites to a PK model predicting GSH depletion with increasing CP exposure. Key information required to develop the model were available from literature studies identifying: 1) microsomal metabolites of CP, and 2) in vitro rates of clearance of CP and 1-CEO from active microsomal preparations from mice, rats, hamsters and humans. Results: Model simulation of concentration dependence of disproportionate increases in reactive metabolite concentrations as exposures increases and decreases in tissue GSH are consistent with the dose-dependence of tumor formation. At the middle bioassay concentrations with a lung tumor incidence, the predicted tissue GSH is less than 50% background. These simulations of reduction in GSH are also consistent with the gene expression results showing the most sensitive pathways are Nrf2-regulation of oxidative stress and GSH metabolism. Discussion: The PBPK model is used to correlate predicted tissue exposure to reactive metabolites with toxicity and carcinogenicity of CP.

3.
J Addict Dis ; 38(3): 380-383, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32449488

RESUMO

The Student Osteopathic Medical Association (SOMA) Overdose Prevention Task Force (OPTF) was created with a vision to reduce overdose deaths around the country through osteopathic medical student action and advocacy. With the medical understanding that opioid overdose is a public health crisis and that there are knowledge deficits within patient populations subject to possible overdose and use disorders, our aim is to increase medical education and training within the medical community, starting at the medical student level. Our focus at this time is to create training and distribution programs for naloxone, to advocate for effective Good Samaritan Laws in states where they are lacking, and to increase access to medication-assisted treatments (MAT) in the communities that need them most. Foundational to the mission of the OPTF is education of the general public and medical communities on harm reduction practices and reducing the stigma surrounding substance use. Student leaders are strategically dispersed nationally over 40 campuses to achieve these goals.


Assuntos
Overdose de Drogas/tratamento farmacológico , Educação de Graduação em Medicina/métodos , Naloxona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico , Tratamento de Substituição de Opiáceos/métodos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Humanos , Medicina Osteopática/educação , Política , Faculdades de Medicina , Sociedades Médicas , Estudantes de Medicina
4.
Patient Educ Couns ; 103(10): 2078-2094, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32345574

RESUMO

OBJECTIVE: To assess the effects of interventions aimed at involving older people with multimorbidity in decision-making about their healthcare during primary care consultations. METHODS: Cochrane methodological procedures were applied. Searches covered all relevant trial registries and databases. Randomised controlled trials were identified where interventions had been compared with usual care/ control/ another intervention. A narrative synthesis is presented; meta-analysis was not appropriate. RESULTS: 8160 abstracts and 54 full-text articles were screened. Three studies were included, involving 1879 patient participants. Interventions utilised behaviour change theory; cognitive-behavioural therapy and motivational interviewing; multidisciplinary, holistic patient review and organisational changes. No studies reported the primary outcome 'patient involvement in decision-making about their healthcare'. Patient involvement was evident in the theory underpinning interventions. Certainty of evidence (assessed using GRADE) was limited by small studies and inconsistency in secondary outcomes measured. CONCLUSION: The evidence base is currently too limited to interpret with certainty. Transparency in design and consistency in evaluation, using validated measures, is required for future interventions involving older patients with multimorbidity in decisions about their healthcare. PRACTICE IMPLICATIONS: There is a large gap between clinical guidelines for multimorbidity and an evidence base for implementation of their recommendations during primary care consultations with older people.


Assuntos
Tomada de Decisões , Multimorbidade , Atenção Primária à Saúde , Idoso , Idoso de 80 Anos ou mais , Humanos , Participação do Paciente , Encaminhamento e Consulta
5.
Environ Monit Assess ; 190(9): 523, 2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30116969

RESUMO

Salinity levels are above historical levels in many New England watersheds. We investigated potential sources of salinity in the Pemigewasset River, a relatively undeveloped watershed in northern New England. We utilized a synoptic sampling approach on six occasions between April and September 2011 paired with a novel land use analysis that incorporated traditional watershed and riparian zones as well as a local contributing area. We established background specific conductivity (SC) and found that SC was above established background levels in both the mainstem of the river (peak of 172 µS cm-1) and multiple tributaries. Specific conductivity was highest during low flow conditions (June) indicating potential groundwater storage and release of de-icing salts applied during winter months. Development in the watershed and riparian zone was found to be more strongly associated with elevated SC, compared to roads. The local contributing area was not found to be strongly associated with SC; however, there was evidence that the local contributing area may contribute to SC under low flow conditions.


Assuntos
Monitoramento Ambiental , Rios/química , Salinidade , Água Subterrânea/química , New England , Estações do Ano
6.
J Endocrinol ; 238(3): R173-R183, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30042117

RESUMO

Kisspeptin is a neuropeptide with a critical role in the function of the hypothalamic-pituitary-gonadal (HPG) axis. Kisspeptin is produced by two major populations of neurons located in the hypothalamus, the rostral periventricular region of the third ventricle (RP3V) and arcuate nucleus (ARC). These neurons project to and activate gonadotrophin-releasing hormone (GnRH) neurons (acting via the kisspeptin receptor, Kiss1r) in the hypothalamus and stimulate the secretion of GnRH. Gonadal sex steroids stimulate kisspeptin neurons in the RP3V, but inhibit kisspeptin neurons in the ARC, which is the underlying mechanism for positive- and negative feedback respectively, and it is now commonly accepted that the ARC kisspeptin neurons act as the GnRH pulse generator. Due to kisspeptin's profound effect on the HPG axis, a focus of recent research has been on afferent inputs to kisspeptin neurons and one specific area of interest has been energy balance, which is thought to facilitate effects such as suppressing fertility in those with under- or severe over-nutrition. Alternatively, evidence is building for a direct role for kisspeptin in regulating energy balance and metabolism. Kiss1r-knockout (KO) mice exhibit increased adiposity and reduced energy expenditure. Although the mechanisms underlying these observations are currently unknown, Kiss1r is expressed in adipose tissue and potentially brown adipose tissue (BAT) and Kiss1rKO mice exhibit reduced energy expenditure. Recent studies are now looking at the effects of kisspeptin signalling on behaviour, with clinical evidence emerging of kisspeptin affecting sexual behaviour, further investigation of potential neuronal pathways are warranted.


Assuntos
Metabolismo Energético/fisiologia , Kisspeptinas/metabolismo , Neurônios/fisiologia , Reprodução/fisiologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/fisiologia , Animais , Metabolismo Energético/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Fertilidade/fisiologia , Hormônios Esteroides Gonadais/farmacologia , Hormônio Liberador de Gonadotropina/fisiologia , Humanos , Camundongos , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Receptores de Kisspeptina-1/genética , Receptores de Kisspeptina-1/metabolismo , Reprodução/efeitos dos fármacos , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia
7.
BMC Med Res Methodol ; 17(1): 139, 2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28899354

RESUMO

Focused ethnography is an applied and pragmatic form of ethnography that explores a specific social phenomenon as it occurs in everyday life. Based on the literature a problem-focused research question is formulated before the data collection. The data generation process targets key informants and situations so that relevant results on the pre-defined topic can be obtained within a relatively short time-span. As part of a theory based evaluation of alternative forms of consultation (such as video, phone and email) in primary care we used the focused ethnographic method in a multisite study in general practice across the UK. To date there is a gap in the literature on using focused ethnography in healthcare research.The aim of the paper is to build on the various methodological approaches in health services research by presenting the challenges and benefits we encountered whilst conducing a focused ethnography in British primary care. Our considerations are clustered under three headings: constructing a shared understanding, dividing the tasks within the team, and the functioning of the focused ethnographers within the broader multi-disciplinary team.As a result of using this approach we experienced several advantages, like the ability to collect focused data in several settings simultaneously within in a short time-span. Also, the sharing of experiences and interpretations between the researchers contributed to a more holistic understanding of the research topic. However, mechanisms need to be in place to facilitate and synthesise the observations, guide the analysis, and to ensure that all researchers feel engaged. Reflection, trust and flexibility among the team members were crucial to successfully adopt a team focused ethnographic approach. When used for policy focussed applied healthcare research a team-based multi-sited focused ethnography can uncover practices and understandings that would not be apparent through surveys or interviews alone. If conducted with care, it can provide timely findings within the fast moving context of healthcare policy and research.


Assuntos
Antropologia Cultural/métodos , Atenção Primária à Saúde , Pesquisa sobre Serviços de Saúde , Humanos , Relações Médico-Paciente , Reino Unido
8.
Environ Mol Mutagen ; 58(8): 607-618, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28862355

RESUMO

While insoluble nickel subsulfide (Ni3 S2 ) was carcinogenic in the lung in a 2-year rat bioassay, soluble nickel sulfate hexahydrate (NiSO4* 6H2 O) was not. To investigate whether differences in the cellular responses to these two nickel compounds could underlie their differential activities, we conducted parallel studies to determine the gene expression changes in micro-dissected lung distal airway cells from Fischer 344 rats following inhalation of the two compounds for one and four weeks (6 hr per day, 5 days per week). The results of the Ni3 S2 study have been reported previously; this paper reports the results for NiSO4 and provides a comparative analysis. The cellular responses to NiSO4 were highly similar to those previously reported for Ni3 S2 , and a set of genes was identified whose expression could be used as biomarkers for comparing cellular nickel effects from in vitro or in vivo studies with soluble NiSO4 and particulate Ni3 S2 . Evaluation of the genomic concentration-responses for the two compounds suggests that the highest inhaled concentration in the tumor bioassay for NiSO4 , which was limited by toxicity, may not have achieved the Ni concentrations at which tumors were observed in the Ni3 S2 bioassay. However, several key differences in the immune responses to NiSO4 and Ni3 S2 were identified that may result from the differential intracellular disposition of Ni from NiSO4 entering the cell as an ion rather than as a slowly soluble Ni3 S2 particle. These differences may also contribute to the observation of tumors in the bioassay for Ni3 S2 but not NiSO4 . Environ. Mol. Mutagen. 58:607-618, 2017. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society.


Assuntos
Carcinógenos/toxicidade , Pulmão/efeitos dos fármacos , Níquel/toxicidade , Administração por Inalação , Animais , Líquido da Lavagem Broncoalveolar , Relação Dose-Resposta a Droga , Humanos , Imunidade Celular/efeitos dos fármacos , Pulmão/patologia , Mutagênicos/toxicidade , Ratos
9.
Trials ; 17(1): 524, 2016 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-27788686

RESUMO

BACKGROUND: Study attrition has the potential to compromise a trial's internal and external validity. The aim of the present study was to identify factors associated with participant attrition in a pilot trial of the effectiveness of a novel behavioural support intervention focused on increasing physical activity to reduce smoking, to inform the methods to reduce attrition in a definitive trial. METHODS: Disadvantaged smokers who wanted to reduce but not quit were randomised (N = 99), of whom 61 (62 %) completed follow-up assessments at 16 weeks. Univariable logistic regression was conducted to determine the effects of intervention arm, method of recruitment, and participant characteristics (sociodemographic factors, and lifestyle, behavioural and attitudinal characteristics) on attrition, followed by multivariable logistic regression on those factors found to be related to attrition. RESULTS: Participants with low confidence to quit, and who were undertaking less than 150 mins of moderate and vigorous physical activity per week at baseline were less likely to complete the 16-week follow-up assessment. Exploratory analysis revealed that those who were lost to follow-up early in the trial (i.e., by 4 weeks), compared with those completing the study, were younger, had smoked for fewer years and had lower confidence to quit in the next 6 months. Participants who recorded a higher expired air carbon monoxide reading at baseline were more likely to drop out late in the study, as were those recruited via follow-up telephone calls. Multivariable analyses showed that only completing less than 150 mins of physical activity retained any confidence in predicting attrition in the presence of other variables. CONCLUSIONS: The findings indicate that those who take more effort to be recruited, are younger, are heavier smokers, have less confidence to quit, and are less physically active are more likely to withdraw or be lost to follow-up.


Assuntos
Terapia Comportamental/métodos , Carência Cultural , Terapia por Exercício/métodos , Cooperação do Paciente , Pacientes Desistentes do Tratamento , Pobreza , Fumantes/psicologia , Redução do Consumo de Tabaco/métodos , Fumar/terapia , Adulto , Fatores Etários , Inglaterra , Feminino , Redução do Dano , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Motivação , Análise Multivariada , Razão de Chances , Projetos Piloto , Fatores de Risco , Fumar/psicologia , Fatores de Tempo , Resultado do Tratamento
10.
Eur J Clin Nutr ; 69(12): 1344-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26130299

RESUMO

Following periods of physical activity, it is not uncommon for exercisers to increase their energy intake as a reward deemed 'earned'. Consumers' awareness of the energy within food and expended from exercise has previously been found to be limited. Therefore, the aim was to investigate whether habitual exercisers (50 adults and 49 children from 5 sports clubs) were able to conceptualise the energy expenditure (EE), following 1 h of their regular sports training, into a quantifiable amount of perceived energy compensation (PEC) in the form of food (chocolate) or drink (sports drink). Mean percentage accuracy for the PEC against EE matched <30% (± 29%), a significant underestimation irrespective of sex or sport. Percentage accuracy failed to significantly correlate to age. These findings indicate a necessity to improve nutrition education surrounding the energy costs of exercise relative to the energy contained within foods/drinks for both adults and children.


Assuntos
Ingestão de Energia , Metabolismo Energético , Exercício Físico , Esportes , Adolescente , Adulto , Fatores Etários , Bebidas , Índice de Massa Corporal , Criança , Feminino , Alimentos , Futebol Americano , Hóquei , Humanos , Masculino , Pessoa de Meia-Idade , Esportes com Raquete , Fatores Sexuais , Natação , Adulto Jovem
11.
Diabetes Res Clin Pract ; 107(2): 247-58, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25533855

RESUMO

AIMS: To determine which patient characteristics were associated with failure to receive indicated care for diabetes over time. METHODS: English Longitudinal Study of Ageing participants aged 50 or older with diabetes reported receipt of care described by four diabetes quality indicators (QIs) in 2008-9 and 2010-11. Annual checks for glycated haemoglobin (HbA1c), proteinuria and foot examination were assessed as a care bundle (n=907). A further QI (n=759) assessed whether participants with cardiac risk factors were offered ACE inhibitors or angiotensin II receptor blockers (ARBs). Logistic regression modelled associations between failure to receive indicated care in 2010-11 and participants' socio-demographic, lifestyle and health characteristics, diabetes self-management knowledge, health literacy, and previous QI achievement in 2008-9. RESULTS: A third of participants (2008-9=32.8%; 2010-11=32.2%) did not receive all annual checks in the care bundle. Nearly half of those eligible were not offered ACE inhibitors/ARBs (2008-9=44.6%; 2010-11=44.5%). Failure to receive a complete care bundle was associated with lower diabetes self-management knowledge (odds ratio (OR) 2.05), poorer cognitive performance (1.78), or having previously received incomplete care (3.32). Participants who were single (OR=2.16), had low health literacy (1.50) or had received incomplete care previously (6.94) were more likely to not be offered ACE inhibitors/ARBs. Increasing age (OR=0.76) or body mass index (OR=0.70) was associated with lower odds of failing to receive this aspect of care. CONCLUSIONS: Quality improvement initiatives for diabetes might usefully target patients with previous receipt of incomplete care, poor knowledge of annual diabetes care processes, and poorer cognition and health literacy.


Assuntos
Atenção à Saúde/normas , Diabetes Mellitus Tipo 2/tratamento farmacológico , Disparidades em Assistência à Saúde/normas , Hipoglicemiantes/uso terapêutico , Pacotes de Assistência ao Paciente/normas , Qualidade da Assistência à Saúde/normas , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Estudos de Coortes , Diabetes Mellitus Tipo 2/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hipertensão/tratamento farmacológico , Entrevistas como Assunto , Estilo de Vida , Modelos Logísticos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Valor Preditivo dos Testes , Estudos Retrospectivos
12.
Toxicol Appl Pharmacol ; 280(1): 78-85, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24976557

RESUMO

Male and female Fischer 344 rats were exposed to naphthalene vapors at 0 (controls), 0.1, 1, 10, and 30ppm for 6h/d, 5 d/wk, over a 90-day period. Following exposure, the respiratory epithelium and olfactory epithelium from the nasal cavity were dissected separately, RNA was isolated, and gene expression microarray analysis was conducted. Only a few significant gene expression changes were observed in the olfactory or respiratory epithelium of either gender at the lowest concentration (0.1ppm). At the 1.0ppm concentration there was limited evidence of an oxidative stress response in the respiratory epithelium, but not in the olfactory epithelium. In contrast, a large number of significantly enriched cellular pathway responses were observed in both tissues at the two highest concentrations (10 and 30ppm, which correspond to tumorigenic concentrations in the NTP bioassay). The nature of these responses supports a mode of action involving oxidative stress, inflammation and proliferation. These results are consistent with a dose-dependent transition in the mode of action for naphthalene toxicity/carcinogenicity between 1.0 and 10ppm in the rat. In the female olfactory epithelium (the gender/site with the highest incidences of neuroblastomas in the NTP bioassay), the lowest concentration at which any signaling pathway was significantly affected, as characterized by the median pathway benchmark dose (BMD) or its 95% lower bound (BMDL) was 6.0 or 3.7ppm, respectively, while the lowest female olfactory BMD values for pathways related to glutathione homeostasis, inflammation, and proliferation were 16.1, 11.1, and 8.4ppm, respectively. In the male respiratory epithelium (the gender/site with the highest incidences of adenomas in the NTP bioassay), the lowest pathway BMD and BMDL were 0.4 and 0.3ppm, respectively, and the lowest male respiratory BMD values for pathways related to glutathione homeostasis, inflammation, and proliferation were 0.5, 0.7, and 0.9ppm, respectively. Using a published physiologically based pharmacokinetic (PBPK) model to estimate target tissue dose relevant to the proposed mode of action (total naphthalene metabolism per gram nasal tissue), the lowest transcriptional BMDLs from this analysis equate to human continuous naphthalene exposure at approximately 0.3ppm. It is unlikely that significant effects of naphthalene or its metabolites will occur at exposures below this concentration.


Assuntos
Exposição por Inalação , Naftalenos/administração & dosagem , Mucosa Nasal/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Administração por Inalação , Animais , Relação Dose-Resposta a Droga , Feminino , Exposição por Inalação/efeitos adversos , Masculino , Mucosa Nasal/patologia , Mucosa Nasal/fisiologia , Ratos , Ratos Endogâmicos F344 , Transcrição Gênica/fisiologia
13.
Toxicol Appl Pharmacol ; 279(3): 441-454, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24952340

RESUMO

OBJECTIVE: To provide insights into the mode of action for Ni3S2 lung carcinogenicity by examining gene expression changes in target cells after inhalation exposure. METHODS: Gene expression changes were determined in micro-dissected lung broncho-alveolar cells from Fischer 344 rats following inhalation of Ni3S2 at 0.0, 0.04, 0.08, 0.15, and 0.60 mg/m(3) (0.03, 0.06, 0.11, and 0.44 mgNi/m(3)) for one and four weeks (6h/day, 5 days/week). RESULTS: Broncho-alveolar lavage fluid evaluation and lung histopathology provided evidence of inflammation only at the two highest concentrations, which were similar to those tested in the 2-year bioassay. The number of statistically significant up- and down-regulated genes decreased markedly from one to four weeks of exposure, suggesting adaptation. Cell signal pathway enrichment at both time-points primarily reflected responses to toxicity, including inflammatory and proliferative signaling. While proliferative signaling was up-regulated at both time points, some inflammatory signaling reversed from down-regulation at 1 week to up-regulation at 4 weeks. CONCLUSIONS: These results support a mode of action for Ni3S2 carcinogenicity driven by chronic toxicity, inflammation and proliferation, leading to mis-replication, rather than by direct genotoxicity. Benchmark dose (BMD) analysis identified the lowest pathway transcriptional BMD exposure concentration as 0.026 mgNi/m(3), for apoptosis/survival signaling. When conducted on the basis of lung Ni concentration the lowest pathway BMD was 0.64 µgNi/g lung, for immune/inflammatory signaling. IMPLICATIONS: These highly conservative BMDs could be used to derive a point of departure in a nonlinear risk assessment for Ni3S2 toxicity and carcinogenicity.


Assuntos
Carcinógenos/toxicidade , Mutagênicos , Níquel/toxicidade , Animais , Apoptose/efeitos dos fármacos , Benchmarking , Peso Corporal/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar/citologia , Carcinógenos/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/patologia , Exposição por Inalação , Pulmão/metabolismo , Pulmão/patologia , Masculino , Análise em Microsséries , Microscopia Eletrônica de Transmissão , Níquel/administração & dosagem , Níquel/metabolismo , Ratos , Ratos Endogâmicos F344 , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
14.
Science ; 343(6169): 1244734, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24324274

RESUMO

Sedimentary rocks examined by the Curiosity rover at Yellowknife Bay, Mars, were derived from sources that evolved from an approximately average martian crustal composition to one influenced by alkaline basalts. No evidence of chemical weathering is preserved, indicating arid, possibly cold, paleoclimates and rapid erosion and deposition. The absence of predicted geochemical variations indicates that magnetite and phyllosilicates formed by diagenesis under low-temperature, circumneutral pH, rock-dominated aqueous conditions. Analyses of diagenetic features (including concretions, raised ridges, and fractures) at high spatial resolution indicate that they are composed of iron- and halogen-rich components, magnesium-iron-chlorine-rich components, and hydrated calcium sulfates, respectively. Composition of a cross-cutting dike-like feature is consistent with sedimentary intrusion. The geochemistry of these sedimentary rocks provides further evidence for diverse depositional and diagenetic sedimentary environments during the early history of Mars.


Assuntos
Exobiologia , Meio Ambiente Extraterreno/química , Sedimentos Geológicos/química , Marte , Baías , Sulfato de Cálcio/análise , Sulfato de Cálcio/química , Cloro/análise , Cloro/química , Óxido Ferroso-Férrico/análise , Óxido Ferroso-Férrico/química , Halogênios/análise , Halogênios/química , Concentração de Íons de Hidrogênio , Ferro/análise , Ferro/química , Magnésio/análise , Magnésio/química , Silicatos/análise , Silicatos/química , Água/química
15.
Science ; 343(6169): 1245267, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24324276

RESUMO

H2O, CO2, SO2, O2, H2, H2S, HCl, chlorinated hydrocarbons, NO, and other trace gases were evolved during pyrolysis of two mudstone samples acquired by the Curiosity rover at Yellowknife Bay within Gale crater, Mars. H2O/OH-bearing phases included 2:1 phyllosilicate(s), bassanite, akaganeite, and amorphous materials. Thermal decomposition of carbonates and combustion of organic materials are candidate sources for the CO2. Concurrent evolution of O2 and chlorinated hydrocarbons suggests the presence of oxychlorine phase(s). Sulfides are likely sources for sulfur-bearing species. Higher abundances of chlorinated hydrocarbons in the mudstone compared with Rocknest windblown materials previously analyzed by Curiosity suggest that indigenous martian or meteoritic organic carbon sources may be preserved in the mudstone; however, the carbon source for the chlorinated hydrocarbons is not definitively of martian origin.


Assuntos
Exobiologia , Meio Ambiente Extraterreno/química , Hidrocarbonetos Clorados/análise , Marte , Compostos Orgânicos Voláteis/análise , Baías , Dióxido de Carbono/análise , Dióxido de Carbono/química , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Oxigênio/análise , Oxigênio/química , Sulfetos/análise , Sulfetos/química , Água/análise , Água/química
17.
Health Technol Assess ; 15(44): i-xii, 1-254, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22182828

RESUMO

BACKGROUND: Exercise referral schemes (ERS) aim to identify inactive adults in the primary-care setting. The GP or health-care professional then refers the patient to a third-party service, with this service taking responsibility for prescribing and monitoring an exercise programme tailored to the needs of the individual. OBJECTIVE: To assess the clinical effectiveness and cost-effectiveness of ERS for people with a diagnosed medical condition known to benefit from physical activity (PA). The scope of this report was broadened to consider individuals without a diagnosed condition who are sedentary. DATA SOURCES: MEDLINE; EMBASE; PsycINFO; The Cochrane Library, ISI Web of Science; SPORTDiscus and ongoing trial registries were searched (from 1990 to October 2009) and included study references were checked. METHODS: Systematic reviews: the effectiveness of ERS, predictors of ERS uptake and adherence, and the cost-effectiveness of ERS; and the development of a decision-analytic economic model to assess cost-effectiveness of ERS. RESULTS: Seven randomised controlled trials (UK, n = 5; non-UK, n = 2) met the effectiveness inclusion criteria, five comparing ERS with usual care, two compared ERS with an alternative PA intervention, and one to an ERS plus a self-determination theory (SDT) intervention. In intention-to-treat analysis, compared with usual care, there was weak evidence of an increase in the number of ERS participants who achieved a self-reported 90-150 minutes of at least moderate-intensity PA per week at 6-12 months' follow-up [pooled relative risk (RR) 1.11, 95% confidence interval 0.99 to 1.25]. There was no consistent evidence of a difference between ERS and usual care in the duration of moderate/vigorous intensity and total PA or other outcomes, for example physical fitness, serum lipids, health-related quality of life (HRQoL). There was no between-group difference in outcomes between ERS and alternative PA interventions or ERS plus a SDT intervention. None of the included trials separately reported outcomes in individuals with medical diagnoses. Fourteen observational studies and five randomised controlled trials provided a numerical assessment of ERS uptake and adherence (UK, n = 16; non-UK, n = 3). Women and older people were more likely to take up ERS but women, when compared with men, were less likely to adhere. The four previous economic evaluations identified suggest ERS to be a cost-effective intervention. Indicative incremental cost per quality-adjusted life-year (QALY) estimates for ERS for various scenarios were based on a de novo model-based economic evaluation. Compared with usual care, the mean incremental cost for ERS was £169 and the mean incremental QALY was 0.008, with the base-case incremental cost-effectiveness ratio at £20,876 per QALY in sedentary people without a medical condition and a cost per QALY of £14,618 in sedentary obese individuals, £12,834 in sedentary hypertensive patients, and £8414 for sedentary individuals with depression. Estimates of cost-effectiveness were highly sensitive to plausible variations in the RR for change in PA and cost of ERS. LIMITATIONS: We found very limited evidence of the effectiveness of ERS. The estimates of the cost-effectiveness of ERS are based on a simple analytical framework. The economic evaluation reports small differences in costs and effects, and findings highlight the wide range of uncertainty associated with the estimates of effectiveness and the impact of effectiveness on HRQoL. No data were identified as part of the effectiveness review to allow for adjustment of the effect of ERS in different populations. CONCLUSIONS: There remains considerable uncertainty as to the effectiveness of ERS for increasing activity, fitness or health indicators or whether they are an efficient use of resources in sedentary people without a medical diagnosis. We failed to identify any trial-based evidence of the effectiveness of ERS in those with a medical diagnosis. Future work should include randomised controlled trials assessing the cinical effectiveness and cost-effectivenesss of ERS in disease groups that may benefit from PA. FUNDING: The National Institute for Health Research Health Technology Assessment programme.


Assuntos
Terapia por Exercício/economia , Cooperação do Paciente , Medicina Preventiva/métodos , Atenção Primária à Saúde/métodos , Comportamento Sedentário , Adulto , Análise Custo-Benefício , Tomada de Decisões , Terapia por Exercício/normas , Feminino , Guias como Assunto , Humanos , Masculino , Atividade Motora/fisiologia , Anos de Vida Ajustados por Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Encaminhamento e Consulta/economia , Reino Unido
18.
BMJ ; 343: d6462, 2011 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-22058134

RESUMO

OBJECTIVE: To assess the impact of exercise referral schemes on physical activity and health outcomes. Design Systematic review and meta-analysis. DATA SOURCES: Medline, Embase, PsycINFO, Cochrane Library, ISI Web of Science, SPORTDiscus, and ongoing trial registries up to October 2009. We also checked study references. Study selection Design: randomised controlled trials or non-randomised controlled (cluster or individual) studies published in peer review journals. POPULATION: sedentary individuals with or without medical diagnosis. Exercise referral schemes defined as: clear referrals by primary care professionals to third party service providers to increase physical activity or exercise, physical activity or exercise programmes tailored to individuals, and initial assessment and monitoring throughout programmes. Comparators: usual care, no intervention, or alternative exercise referral schemes. RESULTS: Eight randomised controlled trials met the inclusion criteria, comparing exercise referral schemes with usual care (six trials), alternative physical activity intervention (two), and an exercise referral scheme plus a self determination theory intervention (one). Compared with usual care, follow-up data for exercise referral schemes showed an increased number of participants who achieved 90-150 minutes of physical activity of at least moderate intensity per week (pooled relative risk 1.16, 95% confidence intervals 1.03 to 1.30) and a reduced level of depression (pooled standardised mean difference -0.82, -1.28 to -0.35). Evidence of a between group difference in physical activity of moderate or vigorous intensity or in other health outcomes was inconsistent at follow-up. We did not find any difference in outcomes between exercise referral schemes and the other two comparator groups. None of the included trials separately reported outcomes in individuals with specific medical diagnoses. Substantial heterogeneity in the quality and nature of the exercise referral schemes across studies might have contributed to the inconsistency in outcome findings. Conclusions Considerable uncertainty remains as to the effectiveness of exercise referral schemes for increasing physical activity, fitness, or health indicators, or whether they are an efficient use of resources for sedentary people with or without a medical diagnosis.


Assuntos
Exercício Físico , Atenção Primária à Saúde , Encaminhamento e Consulta , Análise Custo-Benefício , Exercício Físico/fisiologia , Exercício Físico/psicologia , Indicadores Básicos de Saúde , Humanos , Atividade Motora , Aptidão Física , Atenção Primária à Saúde/economia , Qualidade de Vida , Encaminhamento e Consulta/economia
19.
Phys Chem Chem Phys ; 13(16): 7330-9, 2011 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-21390378

RESUMO

It is well known that WO(3) interacts efficiently with H(2) gas in the presence of noble metals (such as Pd, Pt and Au) at elevated temperatures, changing its optical behaviors; and that its crystallinity plays an important role in these interactions. For the first time, we investigated the in situ Raman spectra changes of WO(3) films of different crystal phases, while incorporating Pd catalysts, at elevated temperatures in the presence of H(2). The Pd/WO(3) films were prepared using RF sputtering and subsequently annealed at 300, 400 and 500 °C in air in order to alter the dominant crystal phase. The films were then characterized using SEM, XRD, XPS, and both UV-VIS and Raman spectroscopy. In order to fundamentally study the process, the measurements were conducted when films were interacting with 1% H(2) in synthetic air at elevated sample temperatures (20, 60, 100 and 140 °C). We suggest that the changes of Raman spectra under such conditions to be mainly a function of the crystal phase, transforming from monoclinic to a mix phase of monoclinic and orthorhombic achieved via increasing the annealing temperature. The as-deposited sample consistently shows similar Raman spectra responses at different operating conditions upon H(2) exposure. However, increasing the annealing temperature to 500 °C tunes the optimum H(2) response operating temperature to 60 °C.

20.
Prim Health Care Res Dev ; 12(1): 68-78, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21426616

RESUMO

AIM: To examine whether different methods of administration of a patient questionnaire (PQ) assessing a doctor's professional performance can influence the quality of data collected. BACKGROUND: Patient surveys are important information sources regarding a doctor's professional performance. Previous research across a range of patient outcomes suggests that the method of administration can influence response rates and ratings, although no data that explore how this might influence patients' assessments of a doctor's professional performance are available. METHODS: A volunteer sample of 13 UK doctors from primary care settings undertook a cross-sectional patient survey. Seven doctors distributed patient surveys using exit and touch-tone telephone administration, and six doctors used exit and postal administration. A consecutive sample of up to 40 patients per doctor completed each method of administration; postal and touch-tone surveys were administered retrospectively, whereas the exit surveys were administered prospectively. The GMC (General Medical Council) PQ included nine performance evaluation questions. We examined the response rates, item completion rates and response profiles of exit survey responses with those obtained from either postal or touch-tone telephone methods. RESULTS: The administration methods influence the quality and comparability of data obtained. The exit survey response rate was higher than touch-tone (82.1% versus 37.5%; P < 0.0001) or postal survey (no reminder) (76.7% versus 60.8%; P < 0.0001) administration, but comparable to the postal survey after one reminder (78.3% versus 75.0%; P = 0.39). Item completion rates were comparable for exit and touch-tone surveys (highest rates of missing data 4.1% and 4.6%, respectively), but exit surveys resulted in more missing values than postal surveys (10.3 to 11.7% versus 1.1 to 3.9%). Response profiles varied. Both touch-tone and postal surveys yielded significantly more critical ratings than the exit survey (three of nine items). CONCLUSION: Mixing administration methods requires caution when the data are used to create benchmarks against which a doctor's performance is assessed.


Assuntos
Benchmarking/métodos , Competência Clínica/estatística & dados numéricos , Coleta de Dados/métodos , Assistência ao Paciente/métodos , Inquéritos e Questionários , Adolescente , Adulto , Benchmarking/normas , Distribuição de Qui-Quadrado , Competência Clínica/normas , Estudos Transversais , Feminino , Pesquisas sobre Atenção à Saúde , Política de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Assistência ao Paciente/normas , Assistência ao Paciente/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Tempo , Reino Unido , Adulto Jovem
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