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1.
Arch Environ Contam Toxicol ; 72(3): 449-460, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28238046

RESUMO

The objectives of the present study were to develop methods for propagating western pearlshell (Margaritifera falcata) for laboratory toxicity testing and evaluate acute and chronic toxicity of chromium VI [Cr(VI)] to the pearlshell and a commonly tested mussel (fatmucket, Lampsilis siliquoidea at 20 °C or in association with a co-stressor of elevated temperature (27 °C), zinc (50 µg Zn/L), or nitrate (35 mg NO3/L). A commonly tested invertebrate (amphipod, Hyalella azteca) also was tested in chronic exposures. Newly transformed pearlshell (~1 week old) were successfully cultured and tested in acute 96 h Cr exposures (control survival 100%). However, the grow-out of juveniles in culture for chronic toxicity testing was less successful and chronic 28-day Cr toxicity tests started with 4 month-old pearlshell failed due to low control survival (39-68%). Acute median effect concentration (EC50) for the pearlshell (919 µg Cr/L) and fatmucket (456 µg Cr/L) tested at 20 °C without a co-stressor decreased by a factor of > 2 at elevated temperature but did not decrease at elevated Zn or elevated NO3. Chronic 28-day Cr tests were completed successfully with the fatmucket and amphipod (control survival 83-98%). Chronic maximum acceptable toxicant concentration (MATC) for fatmucket at 20 °C (26 µg Cr/L) decreased by a factor of 2 at elevated temperature or NO3 but did not decrease at elevated Zn. However, chronic MATC for amphipod at 20 °C (13 µg Cr/L) did not decrease at elevated temperature, Zn, or NO3. Acute EC50s for both mussels tested with or without a co-stressor were above the final acute value used to derive United States Environmental Protection Agency acute water quality criterion (WQC) for Cr(VI); however, chronic MATCs for fatmucket at elevated temperature or NO3 and chronic MATCs for the amphipod at 20 °C with or without elevated Zn or NO3 were about equal to the chronic WQC. The results indicate that (1) the elevated temperature increased the acute Cr toxicity to both mussel species, (2) fatmucket was acutely more sensitive to Cr than the pearlshell, (3) elevated temperature or NO3 increased chronic Cr toxicity to fatmucket, and (4) acute WQC are protective of tested mussels with or without a co-stressor; however, the chronic WQC might not protect fatmucket at elevated temperature or NO3 and might not protect the amphipod at 20 °C with or without elevated Zn or NO3.


Assuntos
Anfípodes/fisiologia , Bivalves/fisiologia , Temperatura Alta , Nitratos/toxicidade , Estresse Fisiológico , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Animais , Cromo , Testes de Toxicidade Crônica
2.
Cochrane Database Syst Rev ; (2): CD004294, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23450551

RESUMO

BACKGROUND: The worldwide population is progressively ageing, with an expected increase in morbidity and demand for long-term care. Physical rehabilitation is beneficial in older people, but relatively little is known about effects on long-term care residents. This is an update of a Cochrane review first published in 2009. OBJECTIVES: To evaluate the benefits and harms of rehabilitation interventions directed at maintaining, or improving, physical function for older people in long-term care through the review of randomised and cluster randomised controlled trials. SEARCH METHODS: We searched the trials registers of the following Cochrane entities: the Stroke Group (May 2012), the Effective Practice and Organisation of Care Group (April 2012), and the Rehabilitation and Related Therapies Field (April 2012). In addition, we searched 20 relevant electronic databases, including the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2009, Issue 4), MEDLINE (1966 to December 2009), EMBASE (1980 to December 2009), CINAHL (1982 to December 2009), AMED (1985 to December 2009), and PsycINFO (1967 to December 2009). We also searched trials and research registers and conference proceedings; checked reference lists; and contacted authors, researchers, and other relevant Cochrane entities. We updated our searches of electronic databases in 2011 and listed relevant studies as awaiting assessment. SELECTION CRITERIA: Randomised studies comparing a rehabilitation intervention designed to maintain or improve physical function with either no intervention or an alternative intervention in older people (over 60 years) who have permanent long-term care residency. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed risk of bias and extracted data. We contacted study authors for additional information. The primary outcome was function in activities of daily living. Secondary outcomes included exercise tolerance, strength, flexibility, balance, perceived health status, mood, cognitive status, fear of falling, and economic analyses. We investigated adverse effects, including death, morbidity, and other events. We synthesised estimates of the primary outcome with the mean difference; mortality data, with the risk ratio; and secondary outcomes, using vote-counting. MAIN RESULTS: We included 67 trials, involving 6300 participants. Fifty-one trials reported the primary outcome, a measure of activities of daily living. The estimated effects of physical rehabilitation at the end of the intervention were an improvement in Barthel Index (0 to 100) scores of six points (95% confidence interval (CI) 2 to 11, P = 0.008, seven studies), Functional Independence Measure (0 to 126) scores of five points (95% CI -2 to 12, P = 0.1, four studies), Rivermead Mobility Index (0 to 15) scores of 0.7 points (95% CI 0.04 to 1.3, P = 0.04, three studies), Timed Up and Go test of five seconds (95% CI -9 to 0, P = 0.05, seven studies), and walking speed of 0.03 m/s (95% CI -0.01 to 0.07, P = 0.1, nine studies). Synthesis of secondary outcomes suggested there is a beneficial effect on strength, flexibility, and balance, and possibly on mood, although the size of any such effect is unknown. There was insufficient evidence of the effect on other secondary outcomes. Based on 25 studies (3721 participants), rehabilitation does not increase risk of mortality in this population (risk ratio 0.95, 95% CI 0.80 to 1.13). However, it is possible bias has resulted in overestimation of the positive effects of physical rehabilitation. AUTHORS' CONCLUSIONS: Physical rehabilitation for long-term care residents may be effective, reducing disability with few adverse events, but effects appear quite small and may not be applicable to all residents. There is insufficient evidence to reach conclusions about improvement sustainability, cost-effectiveness, or which interventions are most appropriate. Future large-scale trials are justified.


Assuntos
Assistência de Longa Duração , Reabilitação , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/reabilitação , Terapia por Exercício , Feminino , Instituição de Longa Permanência para Idosos , Humanos , Masculino , Casas de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Cochrane Database Syst Rev ; (4): CD005471, 2008 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-18843691

RESUMO

BACKGROUND: The primary care specialist interface is a key organisational feature of many health care systems. Patients are referred to specialist care when investigation or therapeutic options are exhausted in primary care and more specialised care is needed. Referral has considerable implications for patients, the health care system and health care costs. There is considerable evidence that the referral processes can be improved. OBJECTIVES: To estimate the effectiveness and efficiency of interventions to change outpatient referral rates or improve outpatient referral appropriateness. SEARCH STRATEGY: We conducted electronic searches of the Cochrane Effective Practice and Organisation of Care (EPOC) group specialised register (developed through extensive searches of MEDLINE, EMBASE, Healthstar and the Cochrane Library) (February 2002) and the National Research Register. Updated searches were conducted in MEDLINE and the EPOC specialised register up to October 2007. SELECTION CRITERIA: Randomised controlled trials, controlled clinical trials, controlled before and after studies and interrupted time series of interventions to change or improve outpatient referrals. Participants were primary care physicians. The outcomes were objectively measured provider performance or health outcomes. DATA COLLECTION AND ANALYSIS: A minimum of two reviewers independently extracted data and assessed study quality. MAIN RESULTS: Seventeen studies involving 23 separate comparisons were included. Nine studies (14 comparisons) evaluated professional educational interventions. Ineffective strategies included: passive dissemination of local referral guidelines (two studies), feedback of referral rates (one study) and discussion with an independent medical adviser (one study). Generally effective strategies included dissemination of guidelines with structured referral sheets (four out of five studies) and involvement of consultants in educational activities (two out of three studies). Four studies evaluated organisational interventions (patient management by family physicians compared to general internists, attachment of a physiotherapist to general practices, a new slot system for referrals and requiring a second 'in-house' opinion prior to referral), all of which were effective. Four studies (five comparisons) evaluated financial interventions. One study evaluating change from a capitation based to mixed capitation and fee-for-service system and from a fee-for-service to a capitation based system (with an element of risk sharing for secondary care services) observed a reduction in referral rates. Modest reductions in referral rates of uncertain significance were observed following the introduction of the general practice fundholding scheme in the United Kingdom (UK). One study evaluating the effect of providing access to private specialists demonstrated an increase in the proportion of patients referred to specialist services but no overall effect on referral rates. AUTHORS' CONCLUSIONS: There are a limited number of rigorous evaluations to base policy on. Active local educational interventions involving secondary care specialists and structured referral sheets are the only interventions shown to impact on referral rates based on current evidence. The effects of 'in-house' second opinion and other intermediate primary care based alternatives to outpatient referral appear promising.


Assuntos
Medicina , Pacientes Ambulatoriais , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde , Encaminhamento e Consulta/normas , Especialização , Ensaios Clínicos Controlados como Assunto , Economia Médica , Medicina de Família e Comunidade/economia , Medicina de Família e Comunidade/organização & administração , Medicina de Família e Comunidade/normas , Humanos , Disseminação de Informação , Medicina/organização & administração , Medicina/normas , Atenção Primária à Saúde/economia , Atenção Primária à Saúde/organização & administração , Atenção Primária à Saúde/normas , Encaminhamento e Consulta/economia , Encaminhamento e Consulta/organização & administração
4.
Chemosphere ; 52(1): 135-42, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12729696

RESUMO

Ecological risk assessments of pharmaceuticals are currently difficult because little-to-no aquatic hazard and exposure information exists in the peer-reviewed literature for most therapeutics. Recently several studies have identified fluoxetine, a widely prescribed antidepressant, in municipal effluents. To evaluate the potential aquatic toxicity of fluoxetine, single species laboratory toxicity tests were performed to assess hazard to aquatic biota. Average LC(50) values for Ceriodaphnia dubia, Daphnia magna, and Pimephales promelas were 0.756 (234 microg/l), 2.65 (820 microg/l), and 2.28 microM (705 microg/l), respectively. Pseudokirchneriella subcapitata growth and C. dubia fecundity were decreased by 0.044 (14 microg/l) and 0.72 microM (223 microg/l) fluoxetine treatments, respectively. Oryias latipes survival was not affected by fluoxteine exposure up to a concentration of 28.9 microM (8.9 mg/l). An LC(50) of 15.2 mg/kg was estimated for Chironomus tentans. Hyalella azteca survival was not affected up to 43 mg/kg fluoxetine sediment exposure. Growth lowest observed effect concentrations for C. tentans and H. azteca were 1.3 and 5.6 mg/kg, respectively. Our findings indicate that lowest measured fluoxetine effect levels are an order of magnitude higher than highest reported municipal effluent concentrations.


Assuntos
Antidepressivos de Segunda Geração/toxicidade , Cyprinidae , Daphnia , Fluoxetina/toxicidade , Sedimentos Geológicos/química , Poluentes Químicos da Água/toxicidade , Anfípodes , Animais , Eucariotos , Fertilidade/efeitos dos fármacos , Dose Letal Mediana , Dinâmica Populacional , Medição de Risco , Sobrevida , Eliminação de Resíduos Líquidos
5.
Soc Sci Med ; 114: 129-37, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24929647

RESUMO

Planners, managers and policy makers in modern health services are not without ingenuity - they will always try, try and try again. They face deep-seated or 'wicked' problems, which have complex roots in the labyrinthine structures though which healthcare is delivered. Accordingly, the interventions devised to deal with such stubborn problems usually come in the plural. Many different reforms are devised to deal with a particular stumbling block, which may be implemented sequentially, simultaneously or whenever policy fashion or funding dictates. This paper examines this predicament from the perspective of evidence based policy. How might researchers go about reviewing the evidence when they are faced with multiple or indeed competing interventions addressing the same problem? In the face of this plight a rather unheralded form of research synthesis has emerged, namely the 'typological review'. We critically review the fortunes of this strategy. Separating the putative reforms into series of subtypes and producing a scorecard of their outcomes has the unintended effect of divorcing them all from an understanding of how organisations change. A more fruitful approach may lie in a 'theory-driven review' underpinned by an understanding of dynamics of social change in complex organisations. We test this thesis by examining the primary and secondary research on the many interventions designed to tackle a particularly wicked problem, namely the inexorable rise in demand for healthcare.


Assuntos
Atenção à Saúde/organização & administração , Atenção à Saúde/normas , Medicina Baseada em Evidências , Humanos , Inovação Organizacional , Melhoria de Qualidade , Reino Unido
6.
Implement Sci ; 2: 26, 2007 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-17683558

RESUMO

BACKGROUND: Psychological models can be used to understand and predict behaviour in a wide range of settings. However, they have not been consistently applied to health professional behaviours, and the contribution of differing theories is not clear. The aim of this study was to explore the usefulness of a range of psychological theories to predict health professional behaviour relating to management of upper respiratory tract infections (URTIs) without antibiotics. METHODS: Psychological measures were collected by postal questionnaire survey from a random sample of general practitioners (GPs) in Scotland. The outcome measures were clinical behaviour (using antibiotic prescription rates as a proxy indicator), behavioural simulation (scenario-based decisions to managing URTI with or without antibiotics) and behavioural intention (general intention to managing URTI without antibiotics). Explanatory variables were the constructs within the following theories: Theory of Planned Behaviour (TPB), Social Cognitive Theory (SCT), Common Sense Self-Regulation Model (CS-SRM), Operant Learning Theory (OLT), Implementation Intention (II), Stage Model (SM), and knowledge (a non-theoretical construct). For each outcome measure, multiple regression analysis was used to examine the predictive value of each theoretical model individually. Following this 'theory level' analysis, a 'cross theory' analysis was conducted to investigate the combined predictive value of all significant individual constructs across theories. RESULTS: All theories were tested, but only significant results are presented. When predicting behaviour, at the theory level, OLT explained 6% of the variance and, in a cross theory analysis, OLT 'evidence of habitual behaviour' also explained 6%. When predicting behavioural simulation, at the theory level, the proportion of variance explained was: TPB, 31%; SCT, 26%; II, 6%; OLT, 24%. GPs who reported having already decided to change their management to try to avoid the use of antibiotics made significantly fewer scenario-based decisions to prescribe. In the cross theory analysis, perceived behavioural control (TPB), evidence of habitual behaviour (OLT), CS-SRM cause (chance/bad luck), and intention entered the equation, together explaining 36% of the variance. When predicting intention, at the theory level, the proportion of variance explained was: TPB, 30%; SCT, 29%; CS-SRM 27%; OLT, 43%. GPs who reported that they had already decided to change their management to try to avoid the use of antibiotics had a significantly higher intention to manage URTIs without prescribing antibiotics. In the cross theory analysis, OLT evidence of habitual behaviour, TPB attitudes, risk perception, CS-SRM control by doctor, TPB perceived behavioural control and CS-SRM control by treatment entered the equation, together explaining 49% of the variance in intention. CONCLUSION: The study provides evidence that psychological models can be useful in understanding and predicting clinical behaviour. Taking a theory-based approach enables the creation of a replicable methodology for identifying factors that predict clinical behaviour. However, a number of conceptual and methodological challenges remain.

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