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The mutation profile of the SARS-CoV-2 Omicron (lineage BA.1) variant posed a concern for naturally acquired and vaccine-induced immunity. We investigated the ability of prior infection with an early SARS-CoV-2 ancestral isolate (Australia/VIC01/2020, VIC01) to protect against disease caused by BA.1. We established that BA.1 infection in naïve Syrian hamsters resulted in a less severe disease than a comparable dose of the ancestral virus, with fewer clinical signs including less weight loss. We present data to show that these clinical observations were almost absent in convalescent hamsters challenged with the same dose of BA.1 50 days after an initial infection with ancestral virus. These data provide evidence that convalescent immunity against ancestral SARS-CoV-2 is protective against BA.1 in the Syrian hamster model of infection. Comparison with published pre-clinical and clinical data supports consistency of the model and its predictive value for the outcome in humans. Further, the ability to detect protection against the less severe disease caused by BA.1 demonstrates continued value of the Syrian hamster model for evaluation of BA.1-specific countermeasures.
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COVID-19 , Animais , Cricetinae , Humanos , Convalescença , Mesocricetus , SARS-CoV-2RESUMO
BACKGROUND: The accuracy with which healthcare professionals (HCPs) and risk prediction tools predict outcomes after major lower limb amputation (MLLA) is uncertain. The aim of this study was to evaluate the accuracy of predicting short-term (30 days after MLLA) mortality, morbidity, and revisional surgery. METHODS: The PERCEIVE (PrEdiction of Risk and Communication of outcomE following major lower limb amputation: a collaboratIVE) study was launched on 1 October 2020. It was an international multicentre study, including adults undergoing MLLA for complications of peripheral arterial disease and/or diabetes. Preoperative predictions of 30-day mortality, morbidity, and MLLA revision by surgeons and anaesthetists were recorded. Probabilities from relevant risk prediction tools were calculated. Evaluation of accuracy included measures of discrimination, calibration, and overall performance. RESULTS: Some 537 patients were included. HCPs had acceptable discrimination in predicting mortality (931 predictions; C-statistic 0.758) and MLLA revision (565 predictions; C-statistic 0.756), but were poor at predicting morbidity (980 predictions; C-statistic 0.616). They overpredicted the risk of all outcomes. All except three risk prediction tools had worse discrimination than HCPs for predicting mortality (C-statistics 0.789, 0.774, and 0.773); two of these significantly overestimated the risk compared with HCPs. SORT version 2 (the only tool incorporating HCP predictions) demonstrated better calibration and overall performance (Brier score 0.082) than HCPs. Tools predicting morbidity and MLLA revision had poor discrimination (C-statistics 0.520 and 0.679). CONCLUSION: Clinicians predicted mortality and MLLA revision well, but predicted morbidity poorly. They overestimated the risk of mortality, morbidity, and MLLA revision. Most short-term risk prediction tools had poorer discrimination or calibration than HCPs. The best method of predicting mortality was a statistical tool that incorporated HCP estimation.
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Amputação Cirúrgica , Doença Arterial Periférica , Adulto , Humanos , Morbidade , Extremidade Inferior/cirurgia , Medição de RiscoRESUMO
BACKGROUND: Children with persistent hearing loss due to otitis media with effusion are commonly managed by surgical intervention. A safe, cheap, and effective medical treatment would enhance treatment options. Underpowered, poor-quality trials have found short-term benefit from oral steroids. We aimed to investigate whether a short course of oral steroids would achieve acceptable hearing in children with persistent otitis media with effusion and hearing loss. METHODS: In this individually randomised, parallel, double-blinded, placebo-controlled trial we recruited children aged 2-8 years with symptoms attributable to otitis media with effusion for at least 3 months and with confirmed bilateral hearing loss. Participants were recruited from 20 ear, nose, and throat (ENT), paediatric audiology, and audiovestibular medicine outpatient departments in England and Wales. Participants were randomly allocated (1:1) to sequentially numbered identical prednisolone (oral steroid) or placebo packs by use of computer-generated random permuted block sizes stratified by site and child's age. The primary outcome was audiometry-confirmed acceptable hearing at 5 weeks. All analyses were by intention to treat. This trial is registered with the ISRCTN Registry, number ISRCTN49798431. FINDINGS: Between March 20, 2014, and April 5, 2016, 1018 children were screened, of whom 389 were randomised. 200 were assigned to receive oral steroids and 189 to receive placebo. Hearing at 5 weeks was assessed in 183 children in the oral steroid group and in 180 in the placebo group. Acceptable hearing was observed in 73 (40%) children in the oral steroid group and in 59 (33%) in the placebo group (absolute difference 7% [95% CI -3 to 17], number needed to treat 14; adjusted odds ratio 1·36 [95% CI 0·88-2·11]; p=0·16). There was no evidence of any significant differences in adverse events or quality-of-life measures between the groups. INTERPRETATION: Otitis media with effusion in children with documented hearing loss and attributable symptoms for at least 3 months has a high rate of spontaneous resolution. A short course of oral prednisolone is not an effective treatment for most children aged 2-8 years with persistent otitis media with effusion, but is well tolerated. One in 14 children might achieve improved hearing but not quality of life. Discussions about watchful waiting and other interventions will be supported by this evidence. FUNDING: National Institute for Health Research (NIHR) Health Technology Assessment programme.
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Glucocorticoides/uso terapêutico , Otite Média com Derrame/tratamento farmacológico , Prednisolona/uso terapêutico , Administração Oral , Audiometria , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Glucocorticoides/administração & dosagem , Perda Auditiva/prevenção & controle , Humanos , Masculino , Otite Média com Derrame/complicações , Prednisolona/administração & dosagemRESUMO
PURPOSE: Rehabilitation experiences of lower limb amputees with poorer physical health have not been fully explored. This study aimed to qualitatively explore experiences of rehabilitation amongst patients who had recently undergone amputation due to complications of vascular disease. METHODS: Semi-structured, face-to-face interviews were conducted with 14 patients participating in the PLACEMENT randomised controlled feasibility trial (ISRCTN: 85710690; EudraCT: 2016-003544-37), which investigated the effectiveness of using a perineural catheter for postoperative pain relief following major lower limb amputation. Framework analysis was used to identify key themes and compare participant data. FINDINGS: Three main themes and corresponding sub-themes were identified: (i) other patients as inspiration; (ii) other patients as competition; and (iii) imagined futures. Perceptions relating to other patients played a key role in rehabilitation, providing a source of motivation, support, and competition. Participants' imagined futures were uncertain, and this was compounded by a lack of information and delays in equipment and/or adaptations. CONCLUSIONS: Findings highlight the importance of fellow patients in supporting rehabilitation following lower limb amputation. Enabling contact with other patients should thus be a key consideration when planning rehabilitation. There is a clear unmet need for realistic information relating to post-amputation recovery, tailored to the needs of individual patients.
There is a clear unmet need for patient information on rehabilitation following major lower limb amputation.Information about future mobility - particularly prosthesis use - should be realistic and individually tailored.The key role of fellow patients should be fully considered when planning post-amputation rehabilitation.
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BACKGROUND: Decision-making when considering major lower limb amputation is complex and requires individualized outcome estimation. It is unknown how accurate healthcare professionals or relevant outcome prediction tools are at predicting outcomes at 1-year after major lower limb amputation. METHODS: An international, multicentre prospective observational study evaluating healthcare professional accuracy in predicting outcomes 1 year after major lower limb amputation and evaluation of relevant outcome prediction tools identified in a systematic search of the literature was undertaken. Observed outcomes at 1 year were compared with: healthcare professionals' preoperative predictions of death (surgeons and anaesthetists), major lower limb amputation revision (surgeons) and ambulation (surgeons, specialist physiotherapists and vascular nurse practitioners); and probabilities calculated from relevant outcome prediction tools. RESULTS: A total of 537 patients and 2244 healthcare professional predictions of outcomes were included. Surgeons and anaesthetists had acceptable discrimination (C-statistic = 0.715), calibration and overall performance (Brier score = 0.200) when predicting 1-year death, but performed worse when predicting major lower limb amputation revision and ambulation (C-statistics = 0.627 and 0.662 respectively). Healthcare professionals overestimated the death and major lower limb amputation revision risks. Consultants outperformed trainees, especially when predicting ambulation. Allied healthcare professionals marginally outperformed surgeons in predicting ambulation. Two outcome prediction tools (C-statistics = 0.755 and 0.717, Brier scores = 0.158 and 0.178) outperformed healthcare professionals' discrimination, calibration and overall performance in predicting death. Two outcome prediction tools for ambulation (C-statistics = 0.688 and 0.667) marginally outperformed healthcare professionals. CONCLUSION: There is uncertainty in predicting 1-year outcomes following major lower limb amputation. Different professional groups performed comparably in this study. Two outcome prediction tools for death and two for ambulation outperformed healthcare professionals and may support shared decision-making.
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Amputação Cirúrgica , Pessoal de Saúde , Extremidade Inferior , Humanos , Consultores , Tomada de Decisão Compartilhada , Extremidade Inferior/cirurgiaRESUMO
The golden Syrian hamster (Mesocricetus auratus) is now commonly used in preclinical research for the study of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the assessment of vaccines, drugs and therapeutics. Here, we show that hamsters inoculated via the intranasal route with the same infectious virus dose of prototypical SARS-CoV-2 administered in a different volume present with different clinical signs, weight loss and viral shedding, with a reduced volume resulting in reduced severity of disease similar to that obtained by a 500-fold reduction in the challenge dose. The tissue burden of the virus and the severity of pulmonary pathology were also significantly affected by different challenge inoculum volumes. These findings suggest that a direct comparison between the severity of SARS-CoV-2 variants or studies assessing the efficacy of treatments determined by hamster studies cannot be made unless both the challenge dose and inoculation volume are matched when using the intranasal route. Additionally, analysis of sub-genomic and total genomic RNA PCR data demonstrated no link between sub-genomic and live viral titres and that sub-genomic analyses do not provide any information beyond that provided by more sensitive total genomic PCR.
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COVID-19 , Cricetinae , Animais , Humanos , Mesocricetus , COVID-19/patologia , SARS-CoV-2 , Pulmão , Gravidade do Paciente , Modelos Animais de DoençasRESUMO
INTRODUCTION: Deciding whether to proceed with a major lower limb amputation is life-changing and complex, and it is crucial that the right decision is made at the right time. However, medical specialists are known to poorly predict risk when assessing patients for major surgery, and there is little guidance and research regarding decisions about amputation. The process of shared decision-making between doctors and patients during surgical consultations is also little understood. Therefore, the aim of this study is to analyse in depth the communication, consent, risk prediction and decision-making process in relation to major lower limb amputation. METHODS AND ANALYSIS: Consultations between patients and surgeons at which major lower limb amputation is discussed will be audio-recorded for 10-15 patients. Semi-structured follow-up interviews with patients (and relatives/carers) will then be conducted at two time points: as soon as possible/appropriate after a decision has been reached regarding surgery, and approximately 6 months later. Semi-structured interviews will also be conducted with 10-15 healthcare professionals working in the UK National Health Service (NHS) involved in amputation decision-making. This will include surgeons, anaesthetists and specialist physiotherapists at 2-4 NHS Health Boards/Trusts in Wales and England. Discourse analysis will be used to analyse the recorded consultations; interviews will be analysed thematically. Finally, workshops will be held with patients and healthcare professionals to help synthesise and interpret findings. ETHICS AND DISSEMINATION: The study has been approved by Wales REC 7 (20/WA/0351). Study findings will be published in international peer-reviewed journal(s) and presented at national and international scientific meetings. Findings will also be disseminated to a wide NHS and lay audience via presentations at meetings and written summaries for key stakeholder groups.
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Amputação Cirúrgica , Medicina Estatal , Amputação Cirúrgica/métodos , Comunicação , Humanos , Extremidade Inferior/cirurgia , Pesquisa QualitativaRESUMO
INTRODUCTION: Procalcitonin (PCT) is a biomarker more specific for bacterial infection and responds quicker than other commonly used biomarkers such as C reactive protein, but is not routinely used in the National Health Service (NHS). Studies mainly in adults show that using PCT to guide clinicians may reduce antibiotic use, reduce hospital stay, with no associated adverse effects such as increased rates of hospital re-admission, incomplete treatment of infections, relapse or death. A review conducted for National Institute for Health and Care Excellence recommends further research on PCT testing to guide antibiotic use in children. METHODS AND ANALYSIS: Biomarker-guided duration of Antibiotic Treatment in Children Hospitalised with confirmed or suspected bacterial infection is a multi-centre, prospective, two-arm, individually Randomised Controlled Trial (RCT) with a 28-day follow-up and internal pilot. The intervention is a PCT-guided algorithm used in conjunction with best practice. The control arm is best practice alone. We plan to recruit 1942 children, aged between 72 hours and up to 18 years old, who are admitted to the hospital and being treated with intravenous antibiotics for suspected or confirmed bacterial infection. Coprimary outcomes are duration of antibiotic use and a composite safety measure. Secondary outcomes include time to switch from broad to narrow spectrum antibiotics, time to discharge, adverse drug reactions, health utility and cost-effectiveness. We will also perform a qualitative process evaluation. Recruitment commenced in June 2018 and paused briefly between March and May 2020 due to the COVID-19 pandemic. ETHICS AND DISSEMINATION: The trial protocol was approved by the HRA and NHS REC (North West Liverpool East REC reference 18/NW/0100). We will publish the results in international peer-reviewed journals and present at scientific meetings. TRIAL REGISTRATION NUMBER: ISRCTN11369832.
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Infecções Bacterianas , COVID-19 , Adulto , Idoso , Antibacterianos/uso terapêutico , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Biomarcadores , Criança , Humanos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2RESUMO
Optimised pre-clinical models are required for TB drug development to better predict the pharmacokinetics of anti-tuberculosis (anti-TB) drugs to shorten the time taken for novel drugs and combinations to be approved for clinical trial. Microdialysis can be used to measure unbound drug concentrations in awake freely moving animals in order to describe the pharmacokinetics of drugs in the organs as a continuous sampling technique. The aim of this work was to develop and optimise the microdialysis methodology in guinea pigs to better understand the pharmacokinetics of rifampicin in the lung. In vitro experiments were performed before progressing into in vivo studies because the recovery (concentration of the drug in the tissue fluid related to that in the collected dialysate) of rifampicin was dependent on a variety of experimental conditions. Mass spectrometry of the dialysate was used to determine the impact of flow rate, perfusion fluid and the molecular weight cut-off and membrane length of probes on the recovery of rifampicin at physiologically relevant concentrations. Following determination of probe efficiency and identification of a correlation between rifampicin concentrations in the lung and skeletal muscle, experiments were conducted to measure rifampicin in the sacrospinalis of guinea pigs using microdialysis. Lung concentrations of rifampicin were estimated from the rifampicin concentrations measured in the sacrospinalis. These studies suggest the potential usefulness of the microdialysis methodology to determine drug concentrations of selected anti-TB drugs to support new TB drug development.
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Antituberculosos/análise , Pulmão/química , Microdiálise/métodos , Rifampina/análise , Animais , Desenvolvimento de Medicamentos , Feminino , CobaiasRESUMO
OBJECTIVES: To explore patient experiences, understanding and perceptions of analgesia following major lower limb amputation. DESIGN: Qualitative interview study, conducted as part of a randomised controlled feasibility trial. SETTING: Participants were recruited from two general hospitals in South Wales. PARTICIPANTS: Interview participants were patients enrolled in PLACEMENT (Perineural Local Anaesthetic Catheter aftEr Major lowEr limb amputatioN Trial): a randomised controlled feasibility trial comparing the use of perineural catheter (PNC) versus standard care for postoperative pain relief following major lower limb amputation. PLACEMENT participants who completed 5-day postoperative follow-up, were able and willing to participate in a face-to-face interview, and had consented to be contacted, were eligible to take part in the qualitative study. A total of 20 interviews were conducted with 14 participants: 10 male and 4 female. METHODS: Semi-structured, face-to-face interviews were conducted with participants over two time points: (1) up to 1 month and (2) at least 6 months following amputation. Interviews were audio-recorded, transcribed verbatim and analysed using a framework approach. RESULTS: Interviews revealed unanticipated benefits of PNC usage for postoperative pain relief. Participants valued the localised and continuous nature of this mode of analgesia in comparison to opioids. Concerns about opioid dependence and side effects of pain relief medication were raised by participants in both treatment groups, with some reporting trying to limit their intake of analgesics. CONCLUSIONS: Findings suggest routine placement of a PNC following major lower limb amputation could reduce postoperative pain, particularly for patient groups at risk of postoperative delirium. This method of analgesic delivery also has the potential to reduce preoperative anxiety, alleviate the burden of pain management and minimise opioid use. Future research could further examine the comparison between patient-controlled analgesia and continuous analgesia in relation to patient anxiety and satisfaction with pain management. TRIAL REGISTRATION NUMBER: ISRCTN: 85710690; EudraCT: 2016-003544-37.
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Amputação Cirúrgica , Manejo da Dor , Analgesia Controlada pelo Paciente/métodos , Analgésicos Opioides/uso terapêutico , Feminino , Humanos , Extremidade Inferior/cirurgia , Masculino , Manejo da Dor/métodos , Dor Pós-Operatória/tratamento farmacológico , Pesquisa QualitativaRESUMO
The global pandemic of coronavirus disease (COVID-19) caused by infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to an international thrust to study pathogenesis and evaluate interventions. Experimental infection of hamsters and the resulting respiratory disease is one of the preferred animal models since clinical signs of disease and virus shedding are similar to more severe cases of human COVID-19. The main route of challenge has been direct inoculation of the virus via the intranasal route. To resemble the natural infection, we designed a bespoke natural transmission cage system to assess whether recipient animals housed in physically separate adjacent cages could become infected from a challenged donor animal in a central cage, with equal airflow across the two side cages. To optimise viral shedding in the donor animals, a low and moderate challenge dose were compared after direct intranasal challenge, but similar viral shedding responses were observed and no discernible difference in kinetics. The results from our natural transmission set-up demonstrate that most recipient hamsters are infected within the system developed, with variation in the kinetics and levels of disease between individual animals. Common clinical outputs used for the assessment in directly-challenged hamsters, such as weight loss, are less obvious in hamsters who become infected from naturally acquiring the infection. The results demonstrate the utility of a natural transmission model for further work on assessing the differences between virus strains and evaluating interventions using a challenge system which more closely resembles human infection.
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COVID-19/transmissão , Modelos Animais de Doenças , Mesocricetus , SARS-CoV-2/fisiologia , Animais , COVID-19/patologia , COVID-19/virologia , Cricetinae , Feminino , Pulmão/patologia , Masculino , Cavidade Nasal/patologia , Carga Viral , Eliminação de Partículas ViraisRESUMO
BACKGROUND: Accurate prediction of outcomes following surgery with high morbidity and mortality rates is essential for informed shared decision-making between patients and clinicians. It is unknown how accurately healthcare professionals predict outcomes following major lower-limb amputation (MLLA). Several MLLA outcome-prediction tools have been developed. These could be valuable in clinical practice, but most require validation in independent cohorts before routine clinical use can be recommended. The primary aim of this study is to evaluate the accuracy of healthcare professionals' predictions of outcomes in adult patients undergoing MLLA for complications of chronic limb-threatening ischaemia (CLTI) or diabetes. Secondary aims include the validation of existing outcome-prediction tools. METHOD: This study is an international, multicentre prospective observational study including adult patients undergoing a primary MLLA for CLTI or diabetes. Healthcare professionals' accuracy in predicting outcomes at 30-days (death, morbidity and MLLA revision) and 1-year (death, MLLA revision and ambulation) will be evaluated. Sixteen existing outcome-prediction tools specific to MLLA will be examined for validity. Data collection began on 1 October 2020; the end of follow-up will be 1 May 2022. The C-statistic, Hosmer-Lemeshow test, reclassification tables and Brier score will be used to evaluate the predictive performance of healthcare professionals and prediction tools, respectively. STUDY REGISTRATION AND DISSEMINATION: This study will be registered locally at each centre in accordance with local policies before commencing data collection, overseen by local clinician leads. Results will be disseminated to all centres, and any subsequent presentation(s) and/or publication(s) will follow a collaborative co-authorship model.
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Amputação Cirúrgica , Isquemia Crônica Crítica de Membro , Adulto , Comunicação , Humanos , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto , PrognósticoRESUMO
There is an urgent requirement for safe and effective vaccines to prevent COVID-19. A concern for the development of new viral vaccines is the potential to induce vaccine-enhanced disease (VED). This was reported in several preclinical studies with both SARS-CoV-1 and MERS vaccines but has not been reported with SARS-CoV-2 vaccines. We have used ferrets and rhesus macaques challenged with SARS-CoV-2 to assess the potential for VED in animals vaccinated with formaldehyde-inactivated SARS-CoV-2 (FIV) formulated with Alhydrogel, compared to a negative control vaccine. We showed no evidence of enhanced disease in ferrets or rhesus macaques given FIV except for mild transient enhanced disease seen 7 days after infection in ferrets. This increased lung pathology was observed at day 7 but was resolved by day 15. We also demonstrate that formaldehyde treatment of SARS-CoV-2 reduces exposure of the spike receptor binding domain providing a mechanistic explanation for suboptimal immunity.
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Vaccines against SARS-CoV-2 are urgently required, but early development of vaccines against SARS-CoV-1 resulted in enhanced disease after vaccination. Careful assessment of this phenomena is warranted for vaccine development against SARS CoV-2. Here we report detailed immune profiling after ChAdOx1 nCoV-19 (AZD1222) and subsequent high dose challenge in two animal models of SARS-CoV-2 mediated disease. We demonstrate in rhesus macaques the lung pathology caused by SARS-CoV-2 mediated pneumonia is reduced by prior vaccination with ChAdOx1 nCoV-19 which induced neutralising antibody responses after a single intramuscular administration. In a second animal model, ferrets, ChAdOx1 nCoV-19 reduced both virus shedding and lung pathology. Antibody titre were boosted by a second dose. Data from these challenge models on the absence of enhanced disease and the detailed immune profiling, support the continued clinical evaluation of ChAdOx1 nCoV-19.
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Vacinas contra COVID-19/imunologia , SARS-CoV-2/imunologia , Animais , Anticorpos Neutralizantes/imunologia , ChAdOx1 nCoV-19 , Furões , Macaca mulattaRESUMO
A novel coronavirus, SARS-CoV-2, has been identified as the causative agent of the current COVID-19 pandemic. Animal models, and in particular non-human primates, are essential to understand the pathogenesis of emerging diseases and to assess the safety and efficacy of novel vaccines and therapeutics. Here, we show that SARS-CoV-2 replicates in the upper and lower respiratory tract and causes pulmonary lesions in both rhesus and cynomolgus macaques. Immune responses against SARS-CoV-2 are also similar in both species and equivalent to those reported in milder infections and convalescent human patients. This finding is reiterated by our transcriptional analysis of respiratory samples revealing the global response to infection. We describe a new method for lung histopathology scoring that will provide a metric to enable clearer decision making for this key endpoint. In contrast to prior publications, in which rhesus are accepted to be the preferred study species, we provide convincing evidence that both macaque species authentically represent mild to moderate forms of COVID-19 observed in the majority of the human population and both species should be used to evaluate the safety and efficacy of interventions against SARS-CoV-2. Importantly, accessing cynomolgus macaques will greatly alleviate the pressures on current rhesus stocks.
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COVID-19/imunologia , COVID-19/virologia , Pulmão/patologia , Pulmão/virologia , Animais , Modelos Animais de Doenças , Feminino , Imunidade Celular/fisiologia , Interferon gama/metabolismo , Macaca fascicularis , Macaca mulatta , Masculino , Pandemias , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidadeRESUMO
There is a vital need for authentic COVID-19 animal models to enable the pre-clinical evaluation of candidate vaccines and therapeutics. Here we report a dose titration study of SARS-CoV-2 in the ferret model. After a high (5 × 106 pfu) and medium (5 × 104 pfu) dose of virus is delivered, intranasally, viral RNA shedding in the upper respiratory tract (URT) is observed in 6/6 animals, however, only 1/6 ferrets show similar signs after low dose (5 × 102 pfu) challenge. Following sequential culls pathological signs of mild multifocal bronchopneumonia in approximately 5-15% of the lung is seen on day 3, in high and medium dosed groups. Ferrets re-challenged, after virus shedding ceased, are fully protected from acute lung pathology. The endpoints of URT viral RNA replication & distinct lung pathology are observed most consistently in the high dose group. This ferret model of SARS-CoV-2 infection presents a mild clinical disease.
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COVID-19/imunologia , Modelos Animais de Doenças , Furões/imunologia , SARS-CoV-2/imunologia , Animais , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/farmacologia , Relação Dose-Resposta a Droga , Feminino , Pulmão/imunologia , Pulmão/patologia , RNA Viral/isolamento & purificação , SARS-CoV-2/genética , Replicação Viral/efeitos dos fármacos , Replicação Viral/imunologia , Eliminação de Partículas Virais/efeitos dos fármacos , Eliminação de Partículas Virais/imunologiaRESUMO
OBJECTIVES: To determine the feasibility of undertaking a randomised controlled effectiveness trial evaluating the use of a perineural catheter (PNC) after major lower limb amputation with postoperative pain as the primary outcome. DESIGN: Randomised controlled feasibility trial. SETTING: Two vascular Centres in South Wales, UK. PARTICIPANTS: 50 patients scheduled for major lower limb amputation (below or above knee) for complications of peripheral vascular disease. INTERVENTIONS: The treatment arm received a PNC placed adjacent to the sciatic or tibial nerve at the time of surgery, with continuous infusion of levobupivacaine hydrochloride 0.125% for up to 5 days. The control arm received neither local anaesthetic nor PNC. Both arms received usual perioperative anaesthesia and postoperative analgesia. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcomes were the proportion of eligible patients who were randomised and the proportion of recruited patients who provided primary effectiveness outcome data. Secondary outcomes were: the proportion of recruited patients reaching 2 and 6 month follow-up and supplying pain data; identification of key cost drivers; development of an economic analysis framework for a future effectiveness trial; identification of barriers to recruitment and site set-up; and identification of the best way to measure postoperative pain. RESULTS: Seventy-six of 103 screened patients were deemed eligible over a 10 month period. Fifty (64.5%) of these patients were randomised, with one excluded in the perioperative period. Forty-five (91.3%) of 49 recruited patients provided enough pain scores on a 4-point verbal rating scale to allow primary effectiveness outcome evaluation. Attrition rates were high; 18 patients supplied data at 6 month follow-up. Costs were dominated by length of hospital stay. Patients and healthcare professionals reported that trial processes were acceptable. CONCLUSIONS: Recruitment of patients into a trial comparing PNC use to usual care after major lower limb amputation with postoperative pain measured on a 4-point verbal rating scale is feasible. Evaluation of longer-term symptoms is difficult. TRIAL REGISTRATION NUMBER: ISRCTN: 85 710 690. EudraCT: 2016-003544-37.
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Amputação Cirúrgica , Anestésicos Locais/administração & dosagem , Dor Pós-Operatória/prevenção & controle , Membro Fantasma/prevenção & controle , Adulto , Cotos de Amputação , Anestesia Local/métodos , Esquema de Medicação , Estudos de Viabilidade , Feminino , Humanos , Extremidade Inferior/inervação , Extremidade Inferior/cirurgia , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/etiologia , Membro Fantasma/etiologia , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
BACKGROUND: Children with hearing loss associated with otitis media with effusion (OME) are commonly managed through surgical intervention, hearing aids or watchful waiting. A safe, inexpensive, effective medical treatment would enhance treatment options. Small, poorly conducted trials have found a short-term benefit from oral steroids. OBJECTIVE: To determine the clinical effectiveness and cost-effectiveness of a 7-day course of oral steroids in improving hearing at 5 weeks in children with persistent OME symptoms and current bilateral OME and hearing loss demonstrated by audiometry. DESIGN: Double-blind, individually randomised, placebo-controlled trial. SETTING: Ear, nose and throat outpatient or paediatric audiology and audiovestibular medicine clinics in Wales and England. PARTICIPANTS: Children aged 2-8 years, with symptoms of hearing loss attributable to OME for at least 3 months, a diagnosis of bilateral OME made on the day of recruitment and audiometry-confirmed hearing loss. INTERVENTIONS: A 7-day course of oral soluble prednisolone, as a single daily dose of 20 mg for children aged 2-5 years or 30 mg for 6- to 8-year-olds, or matched placebo. MAIN OUTCOME MEASURES: Acceptable hearing at 5 weeks from randomisation. Secondary outcomes comprised acceptable hearing at 6 and 12 months, tympanometry, otoscopic findings, health-care consultations related to OME and other resource use, proportion of children who had ventilation tube (grommet) surgery at 6 and 12 months, adverse effects, symptoms, functional health status, health-related quality of life, short- and longer-term cost-effectiveness. RESULTS: A total of 389 children were randomised. Satisfactory hearing at 5 weeks was achieved by 39.9% and 32.8% in the oral steroid and placebo groups, respectively (absolute difference of 7.1%, 95% confidence interval -2.8% to 16.8%; number needed to treat = 14). This difference was not statistically significant. The secondary outcomes were consistent with the picture of a small or no benefit, and we found no subgroups that achieved a meaningful benefit from oral steroids. The economic analysis showed that treatment with oral steroids was more expensive and accrued fewer quality-adjusted life-years than treatment as usual. However, the differences were small and not statistically significant, and the sensitivity analyses demonstrated large variation in the results. CONCLUSIONS: OME in children with documented hearing loss and attributable symptoms for at least 3 months has a high rate of spontaneous resolution. Discussions about watchful waiting and other interventions will be enhanced by this evidence. The findings of this study suggest that any benefit from a short course of oral steroids for OME is likely to be small and of questionable clinical significance, and that the treatment is unlikely to be cost-effective and, therefore, their use cannot be recommended. FUTURE WORK: Studies exploring optimal approaches to sharing natural history data and enhancing shared decision-making are needed for this condition. TRIAL REGISTRATION: Current Controlled Trials ISRCTN49798431 and EudraCT 2012-005123-32. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 61. See the NIHR Journals Library website for further project information.
Assuntos
Glucocorticoides/uso terapêutico , Perda Auditiva/tratamento farmacológico , Perda Auditiva/etiologia , Otite Média com Derrame/complicações , Prednisolona/uso terapêutico , Administração Oral , Audiometria , Criança , Pré-Escolar , Análise Custo-Benefício , Método Duplo-Cego , Feminino , Glucocorticoides/efeitos adversos , Glucocorticoides/economia , Nível de Saúde , Humanos , Masculino , Prednisolona/efeitos adversos , Prednisolona/economia , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de VidaRESUMO
BACKGROUND: Pain after major lower limb amputation for peripheral arterial disease (PAD) is a significant problem. A perineural catheter (PNC) can be placed adjacent to the major nerve at the time of amputation with a continuous local anaesthetic infusion given postoperatively to try and reduce pain. Although low-quality observational data suggest that PNC usage reduces postoperative opioid requirements, there are limited data regarding its effect on pain. The aim of PLACEMENT is to explore the feasibility of running an effectiveness trial to assess the impact of a PNC with continuous local anaesthetic infusion, inserted at the time of amputation, on short and medium-term postoperative outcomes. METHODS/DESIGN: Fifty patients undergoing a major lower limb amputation (below or above the knee) for PAD will be recruited from two centres. Patients will be randomised in a 1:1 ratio to receive standard postoperative analgesia, with or without insertion of a PNC and local anaesthetic infusion for the first 5 postoperative days. Outcome data will be captured for the first 5 days, including pain scores (primary outcome, captured three times a day), opioid use, nausea or vomiting, itching, dizziness and complications. Patients will be contacted 2 and 6 months after surgery to assess quality of life, phantom limb pain, chronic stump pain and total healthcare costs. Semi-structured interviews will be conducted with at least 10 patients (dependent on saturation of analytic themes on preliminary coding) purposefully sampled to achieve variation in site and study arm. Interviews will explore patients' perception of post-amputation pain and its treatment, and experience of study processes. Semi-structured interviews with 5-10 health professionals will explore feasibility, fidelity, and acceptability of the study. Data from this pilot will be used to assess feasibility of, and estimate parameters to calculate the sample size for an effectiveness trial. Full ethical approval has been granted (Wales Research Ethics Committee 3 reference number 16/WA/0353). DISCUSSION: PLACEMENT will be the first study to explore the feasibility of running an effectiveness trial on PNC usage for postoperative pain in amputees, and provide parameters to calculate the appropriate sample size for this study. TRIAL REGISTRATION: ISRCTN.com, ISRCTN85710690 . Registered on 21 October 2016. European Clinical Trials Database (EudraCT), 2016-003544-37. Registered on 24 August 2016.
Assuntos
Amputação Cirúrgica/métodos , Anestésicos Locais/administração & dosagem , Cateteres de Demora , Extremidade Inferior/cirurgia , Dor Pós-Operatória/prevenção & controle , Doença Arterial Periférica/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Coleta de Dados , Interpretação Estatística de Dados , Humanos , Projetos PilotoRESUMO
BACKGROUND: Otitis media with effusion (OME) is an accumulation of fluid in the middle ear affecting about 80 % of children by the age of 4 years. While OME usually resolves spontaneously, it can affect speech, behaviour and development. Children with persistent hearing loss associated with OME are usually offered hearing aids or insertion of ventilation tubes through the tympanic membrane. Oral steroids may be a safe and effective treatment for OME, which could be delivered in primary care. Treatment with oral steroids has the potential to benefit large numbers of children and reduce the burden of care on them and on health services. However, previous trials have either been too small with too short a follow-up period, or of too poor quality to give a definite answer. The aim of the Oral Steroids for the Resolution of Otitis Media with Effusion in Children (OSTRICH) trial is to determine if a short course of oral steroids improves the hearing of children with OME in the short and longer term. METHODS/DESIGN: A total of 380 participants (children of 2 to 8 years of age) are recruited from Hospital Ear, Nose and Throat departments in Wales and England. A trained clinician seeks informed consent from parents of children with symptoms for at least 3 months that are attributable to OME and with confirmed bilateral hearing loss at study entry. Participants are randomised to a course of oral steroid or a matched placebo for 1 week. Outcomes include audiometry, tympanometry and otoscopy assessments; symptoms; adverse effects; functional health status; quality of life; resource use; and cost effectiveness. Participants are followed up at 5 weeks, and at 6 and 12 months after the day of randomisation. The primary outcome is audiometry-confirmed satisfactory hearing at 5 weeks. DISCUSSION: An important evidence gap exists regarding the clinical and cost effectiveness of short courses of oral steroid treatment for OME. Identifying an effective, safe, nonsurgical intervention for OME in children for use in primary care would be of great benefit to children, their families and the NHS. ISRCTN: ISRCTN49798431 (Registered 7 December 2012).