Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
BMJ Open ; 14(6): e085125, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830746

RESUMO

INTRODUCTION: Pain and disability after meniscectomy can be a substantial lifelong problem. There are few treatment options, especially for young people. Non-surgical management (rehabilitation) is an option but increasingly surgeons are performing meniscal allograft transplants (MATs) for these individuals. However, this is still an uncommon procedure, and availability and usage of MAT vary widely both in the UK and internationally. It is not known which treatment option is the most effective and cost-effective. METHODS AND ANALYSIS: The Meniscal Transplant surgery or Optimised Rehabilitation trial is an international, multicentre, randomised controlled trial. The aim is to compare the clinical and cost effectiveness of MAT versus an optimised package of individualised, progressive, rehabilitation that we have called personalised knee therapy (PKT).Participants will be recruited from sites across the UK, Australia, Canada and Belgium. The planned 144 participants provide at least 90% power to detect a 10-point difference in the Knee injury and Osteoarthritis Outcome Score (KOOS4) at 24-months post randomisation (primary outcome). A prospectively planned economic evaluation will be conducted from a healthcare system and personal social services perspective. Secondary outcome data including health utility, occupational status, sports participation, mental well-being, further treatment, and adverse events will be collected at 3, 6, 12, 18, and 24 months. Analysis will be on an intention-to-treat basis and reported in-line with the Consolidated Standards of Reporting Trials statement. ETHICS AND DISSEMINATION: The trial was approved by the London-Bloomsbury Research Ethics Committee on 19 August 2022 (22/LO/0327) and Northern Sydney Local Health District Human Research Ethics Committee, NSW, Australia on the 13 March 2023 (2022/ETH01890).Trial results will be disseminated via peer-reviewed publications, presentations at international conferences, in lay summaries and using social media as appropriate.This protocol adheres to the recommended Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) checklist. TRIAL REGISTRATION NUMBER: ISRCTN87336549.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Análise Custo-Benefício , Estudos Multicêntricos como Assunto , Meniscectomia , Meniscos Tibiais/cirurgia , Meniscos Tibiais/transplante , Lesões do Menisco Tibial/cirurgia , Lesões do Menisco Tibial/terapia , Lesões do Menisco Tibial/reabilitação
2.
Health Technol Assess ; 28(22): 1-94, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38695098

RESUMO

Background: The extra benefit of a programme of physiotherapy in addition to advice alone, following first-time traumatic shoulder dislocation, is uncertain. We compared the clinical and cost-effectiveness of a single session of advice with a single session of advice and a programme of physiotherapy. Objective: The primary objective was to quantify and draw inferences about observed differences in the Oxford Shoulder Instability Score between the trial treatment groups 6 months post randomisation, in adults with a first-time traumatic shoulder dislocation. Design: A pragmatic, multicentre, superiority, randomised controlled trial with embedded qualitative study. Setting: Forty-one hospitals in the UK NHS. Participants: Adults with a radiologically confirmed first-time traumatic anterior shoulder dislocation, being managed non-operatively. People with neurovascular complications or bilateral dislocations, and those unable to adhere to trial procedures or unable to attend physiotherapy within 6 weeks of injury, or who had previously been randomised, were excluded. Interventions: All participants received the same initial shoulder examination followed by advice to aid self-management, lasting up to 1 hour and administered by a physiotherapist (control). Participants randomised to receive an additional programme of physiotherapy were offered sessions lasting for up to 30 minutes, over a maximum duration of 4 months from the date of randomisation (intervention). Main outcome measures: The primary outcome measure was the Oxford Shoulder Instability Score. This is a self-completed outcome measure containing 12 questions (0-4 points each), with possible scores from 0 (worst function) to 48 (best function). Measurements were collected at 6 weeks, 3 months, 6 months and 12 months by postal questionnaire; 6 months was the primary outcome time point. The primary health outcome for economic evaluation was the quality-adjusted life-year, in accordance with National Institute of Health and Care Excellence guidelines. Results: Between 14 November 2018 and 14 March 2022, 482 participants were randomised to advice (n = 240) or advice and a programme of physiotherapy (n = 242). Participants were 34% female, with a mean age of 45 years, and treatment arms were balanced at baseline. There was not a statistically significant difference in the primary outcome between advice only and advice plus a programme of physiotherapy at 6 months for the primary intention-to-treat adjusted analysis (favours physiotherapy: 1.5, 95% confidence interval -0.3 to 3.5) or at earlier 3-month and 6-week time points on the Oxford Shoulder Instability Score (0-48; higher scores indicate better function). The probability of physiotherapy being cost-effective at a willingness-to-pay threshold of £30,000 was 0.95. Conclusions: We found little difference in the primary outcome or other secondary outcomes. Advice with additional physiotherapy sessions was found likely to be cost-effective. However, small imprecise incremental costs and quality-adjusted life-years raise questions on whether it is the best use of scarce physiotherapy resources given current service demands. Limitations: Loss to follow-up was 27%; however, the observed standard deviation was much smaller than anticipated. These changes in parameters reduced the number of participants required to observe the planned target difference of four points. Our post hoc sensitivity analysis, accounting for missing data, gives similar results. Future work: Further research should be directed towards optimising self-management strategies. Study registration: This study is registered as ISRCTN63184243. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 16/167/56) and is published in full in Health Technology Assessment; Vol. 28, No. 22. See the NIHR Funding and Awards website for further award information.


The shoulder dislocates (comes out of its socket joint) when the upper end of the arm bone is forced out during an injury. This common problem occurs mostly in men in their 20s and women aged over 80. After the bone is put back in its socket, most people are managed with physiotherapy. In the United Kingdom, once the bone is back in its socket, there is a range of physiotherapy provision: some hospitals offer advice, and some offer advice and a course of additional physiotherapy sessions. We compared advice alone to advice and physiotherapy for people who had a shoulder that had come out of its joint for the first time. Physiotherapy advice and additional sessions included education about the injury and exercises to move and strengthen the shoulder. When we started this project, this was the first time these two treatments had been compared. Our aim was to compare what activities the two groups could do 6 months after injury via a questionnaire. We also compared quality of life and the cost of rehabilitation at 6 weeks, 3 months, 6 months and 12 months after injury. Adults with a shoulder out of its joint and who were not having surgery were asked to take part. All adults who were eligible and consented to take part were assigned, by chance, to either a single session of advice or the same session followed by physiotherapy. Between 14 November 2018 and 14 March 2022 we collected data on 482 people, from 41 NHS sites across the UK. We found at 6 months there was little evidence that additional physiotherapy was better, when compared to advice alone. Cost-effectiveness analysis (comparing changes in costs and quality of life) suggests additional physiotherapy might provide value for money. However, the changes involved are small and uncertain.


Assuntos
Análise Custo-Benefício , Modalidades de Fisioterapia , Luxação do Ombro , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Luxação do Ombro/terapia , Reino Unido
3.
BMJ ; 384: e076925, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233068

RESUMO

OBJECTIVE: To assess the effects of an additional programme of physiotherapy in adults with a first-time traumatic shoulder dislocation compared with single session of advice, supporting materials, and option to self-refer to physiotherapy. DESIGN: Pragmatic, multicentre, randomised controlled trial (ARTISAN). SETTING AND PARTICIPANTS: Trauma research teams at 41 UK NHS Trust sites screened adults with a first time traumatic anterior shoulder dislocation confirmed radiologically, being managed non-operatively. People were excluded if they presented with both shoulders dislocated, had a neurovascular complication, or were considered for surgical management. INTERVENTIONS: One session of advice, supporting materials, and option to self-refer to physiotherapy (n=240) was assessed against the same advice and supporting materials and an additional programme of physiotherapy (n=242). Analyses were on an intention-to-treat basis with secondary per protocol analyses. MAIN OUTCOME MEASURES: The primary outcome was the Oxford shoulder instability score (a single composite measure of shoulder function), measured six months after treatment allocation. Secondary outcomes included the QuickDASH, EQ-5D-5L, and complications. RESULTS: 482 participants were recruited from 40 sites in the UK. 354 (73%) participants completed the primary outcome score (n=180 allocated to advice only, n=174 allocated to advice and physiotherapy). Participants were mostly male (66%), with a mean age of 45 years. No significant difference was noted between advice compared with advice and a programme of physiotherapy at six months for the primary intention-to-treat adjusted analysis (between group difference favouring physiotherapy 1.5 (95% confidence interval -0.3 to 3.5)) or at earlier three month and six week timepoints. Complication profiles were similar across the two groups (P>0.05). CONCLUSIONS: An additional programme of current physiotherapy is not superior to advice, supporting materials, and the option to self-refer to physiotherapy. TRIAL REGISTRATION: Current Controlled Trials ISRCTN63184243.


Assuntos
Instabilidade Articular , Luxação do Ombro , Articulação do Ombro , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Custo-Benefício , Modalidades de Fisioterapia , Qualidade de Vida , Luxação do Ombro/etiologia , Luxação do Ombro/terapia
4.
JAMA Otolaryngol Head Neck Surg ; 149(11): 1047-1056, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37796524

RESUMO

Importance: Head and neck cancers (HNCs) are often diagnosed at advanced clinical stages during their symptomatic phase, leading to a reduced treatment window and poor survival. Screening programs have been suggested as a mitigation strategy. Objective: To examine the effectiveness of current HNC screening programs in improving diagnosis and survival in adults. Evidence Review: This Preferred Reporting Items for Systematic Reviews and Meta-analyses-guided systematic review involved use of peer-reviewed, English-language journal articles identified from MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials between January 1, 2001, and July 15, 2022. Snowballing was applied to retrieve more studies. Eligible articles were original clinical trials and observational studies presenting a universal or risk-targeted screening program of primary HNC in the adult population. Reporting quality was assessed using the JBI's critical appraisal tools. Findings: Database searches yielded 3646 unique citations with an additional 8 studies found via snowballing. Five reviewers assessed the full text of 106 studies. Sixteen articles were ultimately included in the review, involving 4.7 million adults (34.1%-100% male; median age, 30-59 years). Fifteen studies were based in Asia and 1 in Europe (Portugal). Five reported data from randomized clinical trials. An oral inspection conducted once or once every 2 to 3 years was described in 11 studies for screening oral cancer, while multistep screening involving Epstein-Barr virus serologic testing for nasopharyngeal carcinoma delivered every 1 to 4 years was presented in 5. In 4 trials and 6 observational studies, screening significantly increased the detection of localized (stage I/II) tumor or was associated with an increased proportion of diagnoses, respectively, regardless of the population and cancer subsites. Universal screening of asymptomatic adults improved 3- to 5-year overall survival but did not increase cancer-specific survival in 4 trials. Targeted screening improved overall and cancer-specific survival or was associated with improved survival outcomes in 2 trials and 2 observational studies, respectively. Studies had low to medium risks of bias. Conclusions and Relevance: Evidence from the existing literature suggests that a risk-targeted screening program for oral and nasopharyngeal cancers could improve diagnosis and patient survival. Screening adherence, societal cost-effectiveness, and optimal risk stratification of such a program warrant future research, especially in low-incidence settings outside Asia.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Detecção Precoce de Câncer , Herpesvirus Humano 4 , Neoplasias de Cabeça e Pescoço/diagnóstico
5.
Bone Joint J ; 105-B(4): 382-388, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36924175

RESUMO

The aim of this study was to compare the longer-term outcomes of operatively and nonoperatively managed patients treated with a removable brace (fixed-angle removable orthosis) or a plaster cast immobilization for an acute ankle fracture. This is a secondary analysis of a multicentre randomized controlled trial comparing adults with an acute ankle fracture, initially managed either by operative or nonoperative care. Patients were randomly allocated to receive either a cast immobilization or a fixed-angle removable orthosis (removable brace). Data were collected on baseline characteristics, ankle function, quality of life, and complications. The Olerud-Molander Ankle Score (OMAS) was the primary outcome which was used to measure the participant's ankle function. The primary endpoint was at 16 weeks, with longer-term follow-up at 24 weeks and two years. Overall, 436 patients (65%) completed the final two-year follow-up. The mean difference in OMAS at two years was -0.3 points favouring the plaster cast (95% confidence interval -3.9 to 3.4), indicating no statistically significant difference between the interventions. There was no evidence of differences in patient quality of life (measured using the EuroQol five-dimension five-level questionnaire) or Disability Rating Index. This study demonstrated that patients treated with a removable brace had similar outcomes to those treated with a plaster cast in the first two years after injury. A removable brace is an effective alternative to traditional immobilization in a plaster cast for patients with an ankle fracture.


Assuntos
Fraturas do Tornozelo , Humanos , Adulto , Fraturas do Tornozelo/cirurgia , Seguimentos , Qualidade de Vida , Braquetes , Aparelhos Ortopédicos , Moldes Cirúrgicos/efeitos adversos , Resultado do Tratamento
6.
BMC Med Res Methodol ; 22(1): 256, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36183085

RESUMO

BACKGROUND: Assessing the long term effects of many surgical interventions tested in pragmatic RCTs may require extended periods of participant follow-up to assess effectiveness and use patient-reported outcomes that require large sample sizes. Consequently the RCTs are often perceived as being expensive and time-consuming, particularly if the results show the test intervention is not effective. Adaptive, and particularly group sequential, designs have great potential to improve the efficiency and cost of testing new and existing surgical interventions. As a means to assess the potential utility of group sequential designs, we re-analyse data from a number of recent high-profile RCTs and assess whether using such a design would have caused the trial to stop early. METHODS: Many pragmatic RCTs monitor participants at a number of occasions (e.g. at 6, 12 and 24 months after surgery) during follow-up as a means to assess recovery and also to keep participants engaged with the trial process. Conventionally one of the outcomes is selected as the primary (final) outcome, for clinical reasons, with others designated as either early or late outcomes. In such settings, novel group sequential designs that use data from not only the final outcome but also from early outcomes at interim analyses can be used to inform stopping decisions. We describe data from seven recent surgical RCTs (WAT, DRAFFT, WOLLF, FASHION, CSAW, FIXDT, TOPKAT), and outline possible group sequential designs that could plausibly have been proposed at the design stage. We then simulate how these group sequential designs could have proceeded, by using the observed data and dates to replicate how information could have accumulated and decisions been made for each RCT. RESULTS: The results of the simulated group sequential designs showed that for two of the RCTs it was highly likely that they would have stopped for futility at interim analyses, potentially saving considerable time (15 and 23 months) and costs and avoiding patients being exposed to interventions that were either ineffective or no better than standard care. We discuss the characteristics of RCTs that are important in order to use the methodology we describe, particularly the value of early outcomes and the window of opportunity when early stopping decisions can be made and how it is related to the length of recruitment period and follow-up. CONCLUSIONS: The results for five of the RCTs tested showed that group sequential designs using early outcome data would have been feasible and likely to provide designs that were at least as efficient, and possibly more efficient, than the original fixed sample size designs. In general, the amount of information provided by the early outcomes was surprisingly large, due to the strength of correlations with the primary outcome. This suggests that the methods described here are likely to provide benefits more generally across the range of surgical trials and more widely in other application areas where trial designs, outcomes and follow-up patterns are structured and behave similarly.


Assuntos
Futilidade Médica , Registros , Coleta de Dados , Estudos de Viabilidade , Humanos , Tamanho da Amostra
7.
Bone Jt Open ; 3(6): 455-462, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35658671

RESUMO

AIMS: To compare the cost-utility of removable brace compared with cast in the management of adult patients with ankle fracture. METHODS: A within-trial economic evaluation conducted from the UK NHS and personnel social services (PSS) perspective. Health resources and quality-of-life data were collected as part of the Ankle Injury Rehabilitation (AIR) multicentre, randomized controlled trial over a 12-month period using trial case report forms and patient-completed questionnaires. Cost-utility analysis was estimated in terms of the incremental cost per quality adjusted life year (QALY) gained. Estimate uncertainty was explored by bootstrapping, visualized on the incremental cost-effectiveness ratio plane. Net monetary benefit and probability of cost-effectiveness were evaluated at a range of willingness-to-pay thresholds and visualized graphically. RESULTS: The incremental cost and QALYs of using brace over a 12-month period were £46.73 (95% confidence interval (CI) £-9 to £147) and 0.0141 (95% CI -0.005 to 0.033), respectively. The cost per QALY gained was £3,318. The probability of brace being cost-effective at a £30,000 per QALY willingness-to-pay threshold was 88%. The results remained robust to a range of sensitivity analyses. CONCLUSION: This within-trial economic evaluation found that it is probable that using a removable brace provides good value to the NHS when compared to cast, in the management of adults with ankle fracture. Cite this article: Bone Jt Open 2022;3(6):455-462.

8.
Lancet ; 399(10339): 1954-1963, 2022 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-35461618

RESUMO

BACKGROUND: New surgical procedures can expose patients to harm and should be carefully evaluated before widespread use. The InSpace balloon (Stryker, USA) is an innovative surgical device used to treat people with rotator cuff tears that cannot be repaired. We aimed to determine the effectiveness of the InSpace balloon for people with irreparable rotator cuff tears. METHODS: We conducted a double-blind, group-sequential, adaptive randomised controlled trial in 24 hospitals in the UK, comparing arthroscopic debridement of the subacromial space with biceps tenotomy (debridement only group) with the same procedure but including insertion of the InSpace balloon (debridement with device group). Participants had an irreparable rotator cuff tear, which had not resolved with conservative treatment, and they had symptoms warranting surgery. Eligibility was confirmed intraoperatively before randomly assigning (1:1) participants to a treatment group using a remote computer system. Participants and assessors were masked to group assignment. Masking was achieved by using identical incisions for both procedures, blinding the operation note, and a consistent rehabilitation programme was offered regardless of group allocation. The primary outcome was the Oxford Shoulder Score at 12 months. Pre-trial simulations using data from early and late timepoints informed stopping boundaries for two interim analyses. The primary analysis was on a modified intention-to-treat basis, adjusted for the planned interim analysis. The trial was registered with ISRCTN, ISRCTN17825590. FINDINGS: Between June 1, 2018, and July 30, 2020, we assessed 385 people for eligibility, of which 317 were eligible. 249 (79%) people consented for inclusion in the study. 117 participants were randomly allocated to a treatment group, 61 participants to the debridement only group and 56 to the debridement with device group. A predefined stopping boundary was met at the first interim analysis and recruitment stopped with 117 participants randomised. 43% of participants were female, 57% were male. We obtained primary outcome data for 114 (97%) participants. The mean Oxford Shoulder Score at 12 months was 34·3 (SD 11·1) in the debridement only group and 30·3 (10·9) in the debridement with device group (mean difference adjusted for adaptive design -4·2 [95% CI -8·2 to -0·26];p=0·037) favouring control. There was no difference in adverse events between the two groups. INTERPRETATION: In an efficient, adaptive trial design, our results favoured the debridement only group. We do not recommend the InSpace balloon for the treatment of irreparable rotator cuff tears. FUNDING: Efficacy and Mechanism Evaluation Programme, a Medical Research Council and National Institute for Health and Care Research partnership.


Assuntos
Lesões do Manguito Rotador , Artroscopia/métodos , Feminino , Humanos , Masculino , Músculo Esquelético , Lesões do Manguito Rotador/cirurgia , Ombro , Dor de Ombro/cirurgia , Resultado do Tratamento
9.
BMJ ; 374: n1506, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226192

RESUMO

OBJECTIVES: To assess function, quality of life, resource use, and complications in adults treated with plaster cast immobilisation versus a removable brace for ankle fracture. DESIGN: Multicentre randomised controlled trial. SETTING: 20 trauma units in the UK National Health Service. PARTICIPANTS: 669 adults aged 18 years and older with an acute ankle fracture suitable for cast immobilisation: 334 were randomised to a plaster cast and 335 to a removable brace. INTERVENTIONS: A below the knee cast was applied and ankle range of movement exercises started on cast removal. The removable brace was fitted, and ankle range of movement exercises were started immediately. MAIN OUTCOME MEASURES: Primary outcome was the Olerud Molander ankle score at 16 weeks, analysed by intention to treat. Secondary outcomes were Manchester-Oxford foot questionnaire, disability rating index, quality of life, and complications at 6, 10, and 16 weeks. RESULTS: The mean age of participants was 46 years (SD 17 years) and 381 (57%) were women. 502 (75%) participants completed the study. No statistically significant difference was found in the Olerud Molander ankle score between the cast and removable brace groups at 16 weeks (favours brace: 1.8, 95% confidence interval -2.0 to 5.6). No clinically significant differences were found in the Olerud Molander ankle scores at other time points, in the secondary unadjusted, imputed, or per protocol analyses. CONCLUSIONS: Traditional plaster casting was not found to be superior to functional bracing in adults with an ankle fracture. No statistically difference was found in the Olerud Molander ankle score between the trial arms at 16 weeks. TRIAL REGISTRATION: ISRCTN registry ISRCTN15537280.


Assuntos
Fraturas do Tornozelo/terapia , Braquetes , Moldes Cirúrgicos , Adulto , Fraturas do Tornozelo/diagnóstico , Terapia por Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento , Reino Unido
10.
BMJ Open ; 10(11): e040623, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33444204

RESUMO

INTRODUCTION: First-time traumatic anterior shoulder dislocation (TASD) is predominantly managed non-operatively. People sustaining TASD have ongoing pain, disability and future risk of redislocation. There are no published randomised controlled trials (RCTs) comparing different non-operative rehabilitation strategies to ascertain the optimum clinically effective approach after TASD. METHODS AND ANALYSIS: In this multicentre adaptive RCT, with internal pilot, adults with a radiologically confirmed first time TASD treated non-surgically will be screened at a minimum of 30 sites. People with neurovascular complications, bilateral dislocations or are unable to attend physiotherapy will be excluded.Randomisation will be on a 1:1 treatment allocation, stratified by age, hand dominance and site. Participants will receive a single session of advice; or a single session of advice plus offer of further physiotherapy (maximum 4 months). The primary analysis will be the difference in Oxford Shoulder Instability Score at 6 months. A sample size of a minimum of 478 participants will allow us to show a four point difference with 90% power.An embedded qualitative study will explore the participants' experiences of the trial interventions. ETHICS, REGISTRATION AND DISSEMINATION: Funded by NIHR HTA (16/167/56), 1 June 2018; National Research Ethic Committee approved (18/WA/0236), 26 July 2018. First site opened 5 November 2018 and final results will be updated on trial registries and submitted to a peer-reviewed journal and will inform rehabilitation strategies after a TASD. Study Within A Trial (SWAT) funded by MRC (MR/R013748/1), 1 May 2019; registered on the MRC-HTMR All-Ireland Hub (reference number SWAT 121). TRIAL REGISTRATION NUMBER: ISRCTN63184243. (Trial stage: Pre-results).


Assuntos
Instabilidade Articular , Luxação do Ombro , Atividades Cotidianas , Adulto , Idoso , Humanos , Irlanda , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Inquéritos e Questionários
11.
Sci Total Environ ; 645: 1410-1424, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30248863

RESUMO

While wetlands are known as long-term storages or sinks for contaminants, not all are equally effective at trapping phosphorus (P). The prevalence of P-sink behavior in prairie pothole wetlands remains unclear, especially across gradients of human disturbance. The objectives of the current study were three-fold: (1) characterize the spatiotemporal variability of wetland hydrology and wetland water P concentration across a range of prairie potholes; (2) establish the propensity of different pothole wetlands to act as sources or sinks of P; and (3) assess the potential controls of climatic conditions, landscape characteristics, wetland soil physiochemical properties and local hydrology on source versus sink dynamics. Ten intact and three consolidated (i.e., drained) wetlands located in southwestern Manitoba, Canada, were monitored for water level fluctuations and water soluble reactive P (SRP) concentration over two years with contrasting antecedent wetness conditions. Soil cores were also collected to measure soil physiochemical properties such as the equilibrium phosphorus concentration (EPC). Water column SRP concentrations were compared to EPC values to infer the time-variable source versus sink behavior of each of wetland. Statistical analyses were then performed to assess whether the source versus sink behavior of individual wetlands could be linked to their physiographic or hydrologic characteristics. Results show that some wetlands persistently acted as P sinks while others switched between source and sink behavior. Persistent P-sink behavior was more common with intact wetlands, as opposed to consolidated wetlands. Wetland soil texture, storage volume and short-term water level fluctuations appeared to control the source versus sink behavior of individual wetlands. The dominant controls on P-sink behavior identified under dry conditions were, however, different from those identified under wetter conditions. This study therefore highlights the importance of considering the non-stationary nature of P-sorption dynamics and their controls, even at sub-annual timescales, in the prairie pothole region.

12.
PLoS One ; 13(12): e0209546, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30596679

RESUMO

Physicians' motivation plays a vital role in health systems particularly in dense and urban cities, which deal with high volumes of patients in a variety of settings. The loss of physicians due to low motivation to developed countries is also a critical aspect affecting the quality of care in many regions. Fewer studies have explored health provider and particularly physicians' motivation in developing countries, which is critical to health service delivery. In addition, limited relevant tools have been developed and tested in low and middle-income settings like Pakistan. The purpose of this study was to create and test a tool for measuring physician motivation. A tool was developed to explore physicians' motivation in the Lahore district, Pakistan. Three sections of the questionnaire, which included intrinsic, socio-cultural and organizational factors, were tested with a stratified, random sample of 360 physicians from the public and private health facilities. Factor analysis produced six factors for 'intrinsic motivation,' seven for 'organizational motivation' and three for 'socio-cultural motivation' that explained 47.7%, 52.6% and 40.6% of the total variance, respectively. Bartlett's test of sphericity and the KMO were significant. Cronbach's α and confirmatory factor analysis were found satisfactory for all three sections of questionnaires. In addition to identifying important intrinsic, socio-cultural and organizational factors study found the questionnaires reliable and valid and recommend further testing the applicability of the instrument in similar and diverse settings.


Assuntos
Modelos Psicológicos , Motivação , Médicos/psicologia , Adulto , Atitude do Pessoal de Saúde , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão , Inquéritos e Questionários , Adulto Jovem
13.
J Vet Sci ; 12(1): 75-82, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21368566

RESUMO

Oocytes retrieval, in vitro maturation (IVM) and fertilization (IVF) efficiency are inevitable steps towards in vitro production of embryos. In the present study, these parameters were investigated in the ovaries of prepubertal (n = 31) and pubertal (n = 61) black Bengal goats obtained from a slaughterhouse. Nuclear maturation was evaluated upon aspiration and following IVM in TCM-199 (Earle's salt with L-glutamine and sodium bicarbonate) for 27 h at 39°C under 5% CO(2) in humidified air. The oocytes retrieval and efficiency (mean ± SD) per prepubertal and pubertal goats were 5.2 ± 0.6 and 6.8 ± 0.6, and 77.3 ± 0.1% and 80.5 ± 0.6%, respectively. Anaphase I - telophase I stages differed significantly (7.3 ± 0.8 vs. 2.6 ± 0.2, p < 0.05) between the two groups of goats. After IVM, the percentages of metaphase II were significantly higher (66.3 vs. 60.3, p < 0.05) in pubertal goats than in their prepubertal counterparts. The percentages of normal in vitro fertilization (IVF) in Fert-Tyrode's albumin lactate pyruvate of pubertal goat oocytes did not differ between Percoll and swim-up sperm separation methods (36.7 ± 0.9% vs. 32.7 ± 1.3%, p > 0.05). Furthermore, sperm capacitation by heparin alone or in combination with ionomycin did not lead to a significant increase in the normal fertilization rate (34.8 ± 1.7 vs. 32.2 ± 1.5%, respectively) in the oocytes of pubertal goats. In conclusion, the ovaries of pubertal black Bengal goats obtained from the slaughterhouse could be used for in vitro embryo production. However, further optimization of the IVM and IVF techniques are necessary for satisfactory in vitro embryo production.


Assuntos
Desenvolvimento Embrionário/fisiologia , Fertilização in vitro/veterinária , Cabras/embriologia , Oócitos/fisiologia , Animais , Técnicas de Cultura , Feminino , Masculino , Recuperação de Oócitos/veterinária , Ovário/citologia , Maturidade Sexual , Capacitação Espermática , Coleta de Tecidos e Órgãos/veterinária
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA