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1.
N Engl J Med ; 386(8): 744-756, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-34986294

RESUMO

BACKGROUND: Before the emergence of the B.1.617.2 (delta) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), vaccination reduced transmission of SARS-CoV-2 from vaccinated persons who became infected, potentially by reducing viral loads. Although vaccination still lowers the risk of infection, similar viral loads in vaccinated and unvaccinated persons who are infected with the delta variant call into question the degree to which vaccination prevents transmission. METHODS: We used contact-testing data from England to perform a retrospective observational cohort study involving adult contacts of SARS-CoV-2-infected adult index patients. We used multivariable Poisson regression to investigate associations between transmission and the vaccination status of index patients and contacts and to determine how these associations varied with the B.1.1.7 (alpha) and delta variants and time since the second vaccination. RESULTS: Among 146,243 tested contacts of 108,498 index patients, 54,667 (37%) had positive SARS-CoV-2 polymerase-chain-reaction (PCR) tests. In index patients who became infected with the alpha variant, two vaccinations with either BNT162b2 or ChAdOx1 nCoV-19 (also known as AZD1222), as compared with no vaccination, were independently associated with reduced PCR positivity in contacts (adjusted rate ratio with BNT162b2, 0.32; 95% confidence interval [CI], 0.21 to 0.48; and with ChAdOx1 nCoV-19, 0.48; 95% CI, 0.30 to 0.78). Vaccine-associated reductions in transmission of the delta variant were smaller than those with the alpha variant, and reductions in transmission of the delta variant after two BNT162b2 vaccinations were greater (adjusted rate ratio for the comparison with no vaccination, 0.50; 95% CI, 0.39 to 0.65) than after two ChAdOx1 nCoV-19 vaccinations (adjusted rate ratio, 0.76; 95% CI, 0.70 to 0.82). Variation in cycle-threshold (Ct) values (indicative of viral load) in index patients explained 7 to 23% of vaccine-associated reductions in transmission of the two variants. The reductions in transmission of the delta variant declined over time after the second vaccination, reaching levels that were similar to those in unvaccinated persons by 12 weeks in index patients who had received ChAdOx1 nCoV-19 and attenuating substantially in those who had received BNT162b2. Protection in contacts also declined in the 3-month period after the second vaccination. CONCLUSIONS: Vaccination was associated with a smaller reduction in transmission of the delta variant than of the alpha variant, and the effects of vaccination decreased over time. PCR Ct values at diagnosis of the index patient only partially explained decreased transmission. (Funded by the U.K. Government Department of Health and Social Care and others.).


Assuntos
Vacina BNT162 , COVID-19/transmissão , ChAdOx1 nCoV-19 , Transmissão de Doença Infecciosa/prevenção & controle , SARS-CoV-2 , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19 , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Carga Viral
2.
Artigo em Inglês | MEDLINE | ID: mdl-38856828

RESUMO

PURPOSE: In April 2020, the UK Government implemented NHS Test and Trace to provide SARS-CoV-2 quantitative reverse transcription polymerase chain reaction (qRT-PCR) testing for the public, with nose-and-throat swabbing for samples performed by trained staff. Self-swabbing (SS) would allow rapid scale-up of testing capacity and access. Six studies were undertaken to determine whether SS was as effective for detecting SARS-CoV-2 as swabbing performed by trained staff. METHODS: Six prospective studies were conducted between April-October 2020, using six swab/media combinations. Differences between assisted swabbing (AS) and SS were evaluated for concordance, positivity, sensitivity, cycle threshold (Ct) values and void rates. Statistical analysis was performed using 95% confidence intervals (CIs), paired t-tests and model-based methods. RESULTS: Overall, 3,253 individuals were recruited (median age 37 years, 49% female), with 2,933 having valid paired qRT-PCR results. Pooled concordance rate was 98% (95% CI: 96%, 99%). Positivity rate differences for SS (8.1%) and AS (8.4%) and differences in pooled sensitivities between SS (86%; 95% CI: 78%, 92%) and AS (91%; 95% CI: 78%, 96%) were nonsignificant. Both types of swabbing led to pooled void rates below 2% and strongly correlated Ct values. Age, sex and previous swabbing experience did not have a significant impact on concordance or sensitivity. CONCLUSION: The UK adopted a policy to promote self-testing for SARS-CoV-2 based on data demonstrating equivalence of SS versus AS. Positive outcomes with SS are likely generalisable to testing for other respiratory pathogens, and we consider self-sampling and self-testing essential for future pandemic preparedness.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38860584

RESUMO

BACKGROUND: Many individuals with chronic obstructive pulmonary disease (COPD) experience frequent hospitalization and readmissions, which is burdensome on the health system. This study aims to investigate factors associated with unplanned readmissions and mortality following a COPD-related hospitalization over a 12-month period in Australia, focusing on mental disorders and accounting for the acute phase of the COVID-19 pandemic. METHODS: A retrospective cohort study using linked hospitalization and mortality records identified individuals aged ≥40 years who had at least one hospital admission with a principal diagnosis of COPD between 2014 and 2020 in New South Wales, Australia. A semi-competing risk analysis was conducted to examine factors associated with unplanned readmission and mortality. RESULTS: Adults with a mental disorder diagnosis, specifically anxiety, had a higher risk of 12-month unplanned readmission. Individuals with anxiety and dementia also had a higher risk of mortality pre- and post-unplanned readmission. Individuals who were admitted during the acute phase of the COVID-19 pandemic period had lower risk of unplanned readmission, but higher risk of mortality without unplanned readmission. CONCLUSION: Interventions aimed at reducing admissions should consider adults living with mental disorders such as anxiety or dementia to improve healthcare delivery and health outcomes for individuals living with COPD.

4.
Sensors (Basel) ; 24(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38400456

RESUMO

Distributed optical fibre sensing (DOFS)-based strain measurement systems are now routinely deployed across infrastructure health monitoring applications. However, there are still practical performance and measurement issues associated with the fibre's attachment method, particularly with thermoplastic pipeline materials (e.g., high-density polyethylene, HDPE) and adhesive affixment methods. In this paper, we introduce a new optical fibre installation method that utilises a hot-weld encapsulation approach that fully embeds the fibre onto the pipeline's plastic surface. We describe the development, application and benefits of the new embedment approach (as compared to adhesive methods) and illustrate its practical performance via a full-scale, real-world, dynamic loading trial undertaken on a 1.8 m diameter, 6.4 m long stormwater pipeline structure constructed from composite spiral-wound, steel-reinforced, HDPE pipe. The optical frequency domain reflectometry (OFDR)-based strain results show how the new method improves strain transference and dynamic measurement performance and how the data can be easily interpreted, in a practical context, without the need for complex strain transfer functions. Through the different performance tests, based on UK rail-road network transport loading conditions, we also show how centimetre- to metre-scale strain variations can be clearly resolved at the frequencies and levels consistent with transport- and construction-based, buried infrastructure loading scenarios.

5.
J Clin Monit Comput ; 37(2): 409-420, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36149575

RESUMO

We recently developed a model-based method for analyzing multiple breath nitrogen washout data that does not require identification of Phase-III. In the present study, we assessed the effect of irregular breathing patterns on the intra-subject variabilities of the model parameters. Nitrogen fraction at the mouth was measured in 18 healthy and 20 asthmatic subjects during triplicate performances of multiple breath nitrogen washout, during controlled (target tidal volume 1 L at 8-12 breaths per minute) and free (unrestricted) breathing. The parameters Scond, Sacin and functional residual capacity (FRC) were obtained by conventional analysis of the slope of Phase-III. Fitting the model to the washout data provided functional residual capacity (FRCM), dead space volume (VD), the coefficient of variation of regional specific ventilation ([Formula: see text]), and the model equivalent of Sacin (Sacin-M). Intra-participant coefficients of variation for the model parameters for both health and asthma were FRCM < 5.2%, VD < 5.4%, [Formula: see text] < 9.0%, and Sacin-M < 45.6% for controlled breathing, and FRCM < 4.6%, VD < 5.3%, [Formula: see text] < 13.2%, and Sacin-M < 103.2% for free breathing. The coefficients of variation limits for conventional parameters were FRC < 6.1%, with Scond < 73.6% and Sacin < 49.2% for controlled breathing and Scond < 35.0% and Sacin < 74.4% for free breathing. The model-fitting approach to multiple breath nitrogen washout analysis provides a measure of regional ventilation heterogeneity in [Formula: see text] that is less affected by irregularities in the breathing pattern than its corresponding Phase-III slope analysis parameter Scond.


Assuntos
Asma , Nitrogênio , Humanos , Testes de Função Respiratória/métodos , Pulmão , Respiração
6.
J Digit Imaging ; 36(4): 1376-1389, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37069451

RESUMO

We present a novel algorithm that is able to generate deep synthetic COVID-19 pneumonia CT scan slices using a very small sample of positive training images in tandem with a larger number of normal images. This generative algorithm produces images of sufficient accuracy to enable a DNN classifier to achieve high classification accuracy using as few as 10 positive training slices (from 10 positive cases), which to the best of our knowledge is one order of magnitude fewer than the next closest published work at the time of writing. Deep learning with extremely small positive training volumes is a very difficult problem and has been an important topic during the COVID-19 pandemic, because for quite some time it was difficult to obtain large volumes of COVID-19-positive images for training. Algorithms that can learn to screen for diseases using few examples are an important area of research. Furthermore, algorithms to produce deep synthetic images with smaller data volumes have the added benefit of reducing the barriers of data sharing between healthcare institutions. We present the cycle-consistent segmentation-generative adversarial network (CCS-GAN). CCS-GAN combines style transfer with pulmonary segmentation and relevant transfer learning from negative images in order to create a larger volume of synthetic positive images for the purposes of improving diagnostic classification performance. The performance of a VGG-19 classifier plus CCS-GAN was trained using a small sample of positive image slices ranging from at most 50 down to as few as 10 COVID-19-positive CT scan images. CCS-GAN achieves high accuracy with few positive images and thereby greatly reduces the barrier of acquiring large training volumes in order to train a diagnostic classifier for COVID-19.


Assuntos
COVID-19 , Pandemias , Humanos , COVID-19/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Pulmão , Processamento de Imagem Assistida por Computador/métodos
7.
Lancet ; 398(10307): 1217-1229, 2021 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-34534517

RESUMO

BACKGROUND: School-based COVID-19 contacts in England have been asked to self-isolate at home, missing key educational opportunities. We trialled daily testing of contacts as an alternative to assess whether this resulted in similar control of transmission, while allowing more school attendance. METHODS: We did an open-label, cluster-randomised, controlled trial in secondary schools and further education colleges in England. Schools were randomly assigned (1:1) to self-isolation of school-based COVID-19 contacts for 10 days (control) or to voluntary daily lateral flow device (LFD) testing for 7 days with LFD-negative contacts remaining at school (intervention). Randomisation was stratified according to school type and size, presence of a sixth form, presence of residential students, and proportion of students eligible for free school meals. Group assignment was not masked during procedures or analysis. Coprimary outcomes in all students and staff were COVID-19-related school absence and symptomatic PCR-confirmed COVID-19, adjusted for community case rates, to estimate within-school transmission (non-inferiority margin <50% relative increase). Analyses were done on an intention-to-treat basis using quasi-Poisson regression, also estimating complier average causal effects (CACE). This trial is registered with the ISRCTN registry, ISRCTN18100261. FINDINGS: Between March 18 and May 4, 2021, 204 schools were taken through the consent process, during which three decided not to participate further. 201 schools were randomly assigned (control group n=99, intervention group n=102) in the 10-week study (April 19-May 10, 2021), which continued until the pre-appointed stop date (June 27, 2021). 76 control group schools and 86 intervention group schools actively participated; additional national data allowed most non-participating schools to be included in analysis of coprimary outcomes. 2432 (42·4%) of 5763 intervention group contacts participated in daily contact testing. There were 657 symptomatic PCR-confirmed infections during 7 782 537 days-at-risk (59·1 per 100 000 per week) in the control group and 740 during 8 379 749 days-at-risk (61·8 per 100 000 per week) in the intervention group (intention-to-treat adjusted incidence rate ratio [aIRR] 0·96 [95% CI 0·75-1·22]; p=0·72; CACE aIRR 0·86 [0·55-1·34]). Among students and staff, there were 59 422 (1·62%) COVID-19-related absences during 3 659 017 person-school-days in the control group and 51 541 (1·34%) during 3 845 208 person-school-days in the intervention group (intention-to-treat aIRR 0·80 [95% CI 0·54-1·19]; p=0·27; CACE aIRR 0·61 [0·30-1·23]). INTERPRETATION: Daily contact testing of school-based contacts was non-inferior to self-isolation for control of COVID-19 transmission, with similar rates of symptomatic infections among students and staff with both approaches. Infection rates in school-based contacts were low, with very few school contacts testing positive. Daily contact testing should be considered for implementation as a safe alternative to home isolation following school-based exposures. FUNDING: UK Government Department of Health and Social Care.


Assuntos
Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Controle de Doenças Transmissíveis/métodos , Quarentena/métodos , Instituições Acadêmicas , Adolescente , Adulto , Idoso , COVID-19/prevenção & controle , COVID-19/transmissão , Teste de Ácido Nucleico para COVID-19 , Teste para COVID-19/métodos , Criança , Pessoal de Educação , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Adulto Jovem
8.
Respirology ; 27(9): 688-719, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35981737

RESUMO

The Thoracic Society of Australia and New Zealand (TSANZ) and the Australian and New Zealand Society of Respiratory Science (ANZSRS) commissioned a joint position paper on pulmonary function testing during coronavirus disease 2019 (COVID-19) in July 2021. A working group was formed via an expression of interest to members of both organizations and commenced work in September 2021. A rapid review of the literature was undertaken, with a 'best evidence synthesis' approach taken to answer the research questions formed. This allowed the working group to accept findings of prior relevant reviews or societal document where appropriate. The advice provided is for providers of pulmonary function tests across all settings. The advice is intended to supplement local infection prevention and state, territory or national directives. The working group's key messages reflect a precautionary approach to protect the safety of both healthcare workers (HCWs) and patients in a rapidly changing environment. The decision on strategies employed may vary depending on local transmission and practice environment. The advice is likely to require review as evidence grows and the COVID-19 pandemic evolves. While this position statement was contextualized specifically to the COVID-19 pandemic, the working group strongly advocates that any changes to clinical/laboratory practice, made in the interest of optimizing the safety and well-being of HCWs and patients involved in pulmonary function testing, are carefully considered in light of their potential for ongoing use to reduce transmission of other droplet and/or aerosol borne diseases.


Assuntos
COVID-19 , SARS-CoV-2 , Austrália/epidemiologia , COVID-19/diagnóstico , COVID-19/epidemiologia , Humanos , Nova Zelândia , Pandemias/prevenção & controle , Testes de Função Respiratória
9.
J Virol ; 94(21)2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796064

RESUMO

African swine fever virus (ASFV) causes a lethal hemorrhagic disease of domestic pigs, against which no vaccine is available. ASFV has a large, double-stranded DNA genome that encodes over 150 proteins. Replication takes place predominantly in the cytoplasm of the cell and involves complex interactions with host cellular components, including small noncoding RNAs (sncRNAs). A number of DNA viruses are known to manipulate sncRNA either by encoding their own or disrupting host sncRNA. To investigate the interplay between ASFV and sncRNAs, a study of host and viral small RNAs extracted from ASFV-infected primary porcine macrophages (PAMs) was undertaken. We discovered that ASFV infection had only a modest effect on host miRNAs, with only 6 miRNAs differentially expressed during infection. The data also revealed 3 potential novel small RNAs encoded by ASFV, ASFVsRNA1-3. Further investigation of ASFVsRNA2 detected it in lymphoid tissue from pigs with ASF. Overexpression of ASFVsRNA2 led to an up to 1-log reduction in ASFV growth, indicating that ASFV utilizes a virus-encoded small RNA to disrupt its own replication.IMPORTANCE African swine fever (ASF) poses a major threat to pig populations and food security worldwide. The disease is endemic to Africa and Eastern Europe and is rapidly emerging into Asia, where it has led to the deaths of millions of pigs in the last 12 months. The development of safe and effective vaccines to protect pigs against ASF has been hindered by lack of understanding of the complex interactions between ASFV and the host cell. We focused our work on characterizing the interactions between ASFV and sncRNAs. Although comparatively modest changes to host sncRNA abundances were observed upon ASFV infection, we discovered and characterized a novel functional ASFV-encoded sncRNA. The results from this study add important insights into ASFV host-pathogen interactions. This knowledge may be exploited to develop more effective ASFV vaccines that take advantage of the sncRNA system.


Assuntos
Vírus da Febre Suína Africana/genética , Febre Suína Africana/genética , Genoma Viral , Interações Hospedeiro-Patógeno/genética , MicroRNAs/genética , Pequeno RNA não Traduzido/genética , RNA Viral/genética , Febre Suína Africana/metabolismo , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/metabolismo , Animais , Regulação da Expressão Gênica , Tamanho do Genoma , Tecido Linfoide , Macrófagos , MicroRNAs/classificação , MicroRNAs/metabolismo , Cultura Primária de Células , Pequeno RNA não Traduzido/classificação , Pequeno RNA não Traduzido/metabolismo , RNA Viral/classificação , RNA Viral/metabolismo , Transdução de Sinais , Sus scrofa , Suínos , Replicação Viral
10.
J Urol ; 206(4): 986-993, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34032496

RESUMO

PURPOSE: An ill-defined proportion of patients undergoing urethroplasty fail to experience improvement in lower urinary tract symptoms (LUTS) despite being stricture-free. We aim to identify the incidence, associations and causes of "LUTS failure" after urethroplasty. MATERIALS AND METHODS: Patients undergoing urethroplasty over a 6-year period were offered enrollment in a prospective study examining urinary function after urethroplasty. Patients were assessed preoperatively and 6 months postoperatively using the International Prostate Symptom Score (IPSS) and cystoscopy. "LUTS failure" was defined as ≤3-point improvement in IPSS despite an anatomically successful urethroplasty. Multivariable logistic regression was utilized to evaluate the association between patient factors and "LUTS failure." RESULTS: Of 365 patients meeting inclusion criteria, mean postoperative IPSS (20.3 vs. 5.4, p <0.0001) and median urinary quality of life (UQOL; 5 vs. 1; p <0.0001) were significantly improved. Despite being stricture-free, 7.7% of patients reported "LUTS failure" and 10.1% reported UQOL nonresponse. On multivariable logistic regression, increasing age (OR 1.04, 95% CI 1.01-1.06; p=0.006) and hypospadias (OR 18.2, 95% CI 2.1-156.0; p=0.008) were associated with "LUTS failure," while stricture location (p=0.76), length (p=0.14), previous urethroplasty (p=0.96), failed endoscopic treatment (p=0.17), type of urethroplasty (p=0.93) and other etiologies were not. Qualitatively, the most likely causes of "LUTS failure" were detrusor underactivity (39.3%), overactivity (21.4%), pelvic floor dysfunction (21.4%) or benign prostatic hyperplasia (14.3%). Only increasing age was associated with UQOL nonresponse (OR 1.03, 95% CI 1.01-1.07; p=0.02). CONCLUSIONS: While many patients experience improved voiding function after urethroplasty, 7.7% experience "LUTS failure" and 10.1% report UQOL nonresponse. Both occurrences are independently associated with increasing patient age and most commonly related to detrusor underactivity.


Assuntos
Sintomas do Trato Urinário Inferior/diagnóstico , Procedimentos de Cirurgia Plástica/estatística & dados numéricos , Uretra/cirurgia , Estreitamento Uretral/cirurgia , Procedimentos Cirúrgicos Urológicos Masculinos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Seguimentos , Humanos , Incidência , Sintomas do Trato Urinário Inferior/etiologia , Sintomas do Trato Urinário Inferior/fisiopatologia , Sintomas do Trato Urinário Inferior/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários/estatística & dados numéricos , Falha de Tratamento , Estreitamento Uretral/complicações , Micção/fisiologia , Adulto Jovem
11.
J Digit Imaging ; 34(3): 647-666, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33532893

RESUMO

We present a hybrid algorithm to estimate lung nodule malignancy that combines imaging biomarkers from Radiologist's annotation with image classification of CT scans. Our algorithm employs a 3D Convolutional Neural Network (CNN) as well as a Random Forest in order to combine CT imagery with biomarker annotation and volumetric radiomic features. We analyze and compare the performance of the algorithm using only imagery, only biomarkers, combined imagery + biomarkers, combined imagery + volumetric radiomic features, and finally the combination of imagery + biomarkers + volumetric features in order to classify the suspicion level of nodule malignancy. The National Cancer Institute (NCI) Lung Image Database Consortium (LIDC) IDRI dataset is used to train and evaluate the classification task. We show that the incorporation of semi-supervised learning by means of K-Nearest-Neighbors (KNN) can increase the available training sample size of the LIDC-IDRI, thereby further improving the accuracy of malignancy estimation of most of the models tested although there is no significant improvement with the use of KNN semi-supervised learning if image classification with CNNs and volumetric features is combined with descriptive biomarkers. Unexpectedly, we also show that a model using image biomarkers alone is more accurate than one that combines biomarkers with volumetric radiomics, 3D CNNs, and semi-supervised learning. We discuss the possibility that this result may be influenced by cognitive bias in LIDC-IDRI because malignancy estimates were recorded by the same radiologist panel as biomarkers, as well as future work to incorporate pathology information over a subset of study participants.


Assuntos
Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Biomarcadores , Humanos , Pulmão , Neoplasias Pulmonares/diagnóstico por imagem , Redes Neurais de Computação , Interpretação de Imagem Radiográfica Assistida por Computador , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X
12.
J Interprof Care ; 35(sup1): 26-32, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35068306

RESUMO

Interprofessional care provided in a free community-based clinic that focuses on chronic health conditions and health promotion provides an innovative solution to improve societal health. Many existing clinics provide a range of professions, but few include allied health services such as occupational and physical therapy. This paper provides a description of the development and implementation of an expanded faculty-guided student-led community-based primary care clinic that includes occupational and physical therapists as part of an interprofessional collaborative practice model. A detailed description and explanation of the partners involved, the institutional missions that drive this work, the logistics completed that enabled the 'doors to open,' faculty and student roles, and initial outcomes will be provided. A review of the service delivery model, lessons learned, and future directions for the clinic will also be offered.


Assuntos
Relações Interprofissionais , Terapia Ocupacional , Serviços de Saúde Comunitária , Comportamento Cooperativo , Docentes , Humanos , Modalidades de Fisioterapia , Atenção Primária à Saúde
13.
Am J Physiol Lung Cell Mol Physiol ; 319(4): L693-L709, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783616

RESUMO

Many mouse models of allergic asthma exhibit eosinophil-predominant cellularity rather than the mixed-granulocytic cytology in steroid-unresponsive severe disease. Therefore, we sought to implement a novel mouse model of antigen-driven, mixed-granulocytic, severe allergic asthma to determine biomarkers of the disease process and potential therapeutic targets. C57BL/6J wild-type, interleukin-6 knockout (IL-6-/-), and IL-6 receptor knockout (IL-6R-/-), mice were injected with an emulsion of complete Freund's adjuvant and house dust mite antigen (CFA/HDM) on day 1. Dexamethasone, a lymphocyte-depleting biological, or anti-IL-17A was administered during the intranasal HDM challenge on days 19-22. On day 23, the CFA/HDM model elicited mixed bronchoalveolar lavage (BAL) cellularity (typically 80% neutrophils and 10% eosinophils), airway hyperresponsiveness (AHR) to methacholine, diffusion impairment, lung damage, body weight loss, corticosteroid resistance, and elevated levels of serum amyloid A (SAA), pro-inflammatory cytokines, and T helper type 1/ T helper type 17 (Th1/Th17) cytokines compared with eosinophilic models of HDM-driven allergic airway disease. BAL cells in IL-6- or IL-6R-deficient mice were predominantly eosinophilic and associated with elevated T helper type 2 (Th2) and reduced Th1/Th17 cytokine production, along with an absence of SAA. Nevertheless, AHR remained in IL-6-deficient mice even when dexamethasone was administered. However, combined administration of anti-IL-17A and systemic corticosteroid significantly attenuated both overall and neutrophilic airway inflammation and also reduced AHR and body weight loss. Inhibition of IL-17A combined with systemic corticosteroid treatment during antigen-driven exacerbations may provide a novel therapeutic approach to prevent the pathological pulmonary and constitutional changes that greatly impact patients with the mixed-granulocytic endotype of severe asthma.


Assuntos
Corticosteroides/farmacologia , Asma/tratamento farmacológico , Neutrófilos/efeitos dos fármacos , Células Th17/efeitos dos fármacos , Alérgenos/efeitos dos fármacos , Alérgenos/imunologia , Animais , Asma/patologia , Eosinófilos/efeitos dos fármacos , Eosinófilos/patologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Camundongos Endogâmicos C57BL , Neutrófilos/imunologia , Hipersensibilidade Respiratória/patologia , Células Th17/imunologia
14.
Phys Biol ; 17(5): 056001, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32141440

RESUMO

Trauma arising from landmines and improvised explosive devices promotes heterotopic ossification, the formation of extra-skeletal bone in non-osseous tissue. To date, experimental platforms that can replicate the loading parameter space relevant to improvised explosive device and landmine blast wave exposure have not been available to study the effects of such non-physiological mechanical loading on cells. Here, we present the design and calibration of three distinct in vitro experimental loading platforms that allow us to replicate the spectrum of loading conditions recorded in near-field blast wave exposure. We subjected cells in suspension or in a three-dimensional hydrogel to strain rates up to 6000 s-1 and pressure levels up to 45 MPa. Our results highlight that cellular activation is regulated in a non-linear fashion-not by a single mechanical parameter, it is the combined action of the applied mechanical pressure, rate of loading and loading impulse, along with the extracellular environment used to convey the pressure waves. Finally, our research indicates that PO MSCs are finely tuned to respond to mechanical stimuli that fall within defined ranges of loading.


Assuntos
Materiais Biocompatíveis/química , Explosões , Técnicas In Vitro/métodos , Pressão , Substâncias Explosivas
15.
Pharmacol Res ; 159: 105029, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32565310

RESUMO

Asthma and COPD make up the majority of obstructive airways diseases (OADs), which affects ∼11 % of the population. The main drugs used to treat OADs have not changed in the past five decades, with advancements mainly comprising variations on existing treatments. The recent biologics are beneficial to only specific subsets of patients. Part of this may lie in our inability to adequately characterise the tremendous heterogeneity in every aspect of OAD. The field is currently moving towards the concept of personalised medicine, based on a focus on treatable traits that are objective, measurable and modifiable. We propose extending this concept via the use of emerging clinical tools for comprehensive physiological phenotyping. We describe, based on published data, the evidence for the use of functional imaging, gas washout techniques and oscillometry, as well as potential future applications, to more comprehensively assess and predict treatment response in OADs. In this way, we hope to demonstrate how physiological phenotyping tools will improve the way in which drugs are prescribed, but most importantly, will facilitate development of new drugs for OADs.


Assuntos
Obstrução das Vias Respiratórias/diagnóstico , Pneumopatias Obstrutivas/diagnóstico , Pulmão/diagnóstico por imagem , Testes de Função Respiratória , Obstrução das Vias Respiratórias/tratamento farmacológico , Obstrução das Vias Respiratórias/fisiopatologia , Animais , Tomada de Decisão Clínica , Desenvolvimento de Medicamentos , Humanos , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Pneumopatias Obstrutivas/tratamento farmacológico , Pneumopatias Obstrutivas/fisiopatologia , Medidas de Resultados Relatados pelo Paciente , Fenótipo , Valor Preditivo dos Testes , Medicamentos para o Sistema Respiratório/uso terapêutico
16.
Curr Opin Pulm Med ; 26(1): 97-102, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31652155

RESUMO

PURPOSE OF REVIEW: Electronic cigarettes have quickly risen to be the leading alternative nicotine source to tobacco. E-cigarette use is hard to research and regulate because of the novelty and rapid evolution of the devices and E-liquids. Epidemiological data on long-term usage is currently lacking, but in smaller cohort studies we are starting to understand the usage patterns and demographics of users, which differ depending on where the study takes place and the regulatory environment. The present review describes the current knowledge of the effects of E-cigarettes on the pulmonary system and knowledge of their usage patterns worldwide. RECENT FINDINGS: E-cigarette use is continuing to rise in young adults in United States and Canada, but not in United Kingdom. These suggest that regulation is influencing uptake in young adults. If E-cigarettes are to be considered as a harm minimisation smoking cessation product, use in young never smokers must be factored into the risk assessment. A recent surge in cases of lung injury associated with vaping in America has resulted in the definition of vaping associated pulmonary injury, although the exact cause remains unknown. SUMMARY: It is our opinion that E-cigarettes can no longer be defined as harmless. Further studies are needed to determine the risks for all populations as it is evident that a large proportion of E-cigarette users are never-smokers, meaning they cannot only be considered from a harm reduction perspective.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Lesão Pulmonar , Vaping , Humanos , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/epidemiologia , Lesão Pulmonar/prevenção & controle , Medição de Risco , Vaping/efeitos adversos , Vaping/epidemiologia
17.
Med J Aust ; 213(11): 516-520, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33314108

RESUMO

OBJECTIVE: To characterise the working arrangements of medical research scientists and support staff in Australia during the COVID-19 pandemic, and to evaluate factors (in particular: wearing pyjamas) that influence the self-assessed productivity and mental health of medical institute staff working from home. DESIGN: Prospective cohort survey study, 30 April - 18 May 2020. SETTING, PARTICIPANTS: Staff (scientists and non-scientists) and students at five medical research institutes in Sydney, New South Wales. MAIN OUTCOME MEASURES: Self-assessed overall and task-specific productivity, and mental health. RESULTS: The proportions of non-scientists and scientists who wore pyjamas during the day were similar (3% v 11%; P = 0.31). Wearing pyjamas was not associated with differences in self-evaluated productivity, but was significantly associated with more frequent reporting of poorer mental health than non-pyjama wearers while working from home (59% v 26%; P < 0.001). Having children in the home were significantly associated with changes in productivity. Larger proportions of people with toddlers reported reduced overall productivity (63% v 32%; P = 0.008), and reduced productivity in writing manuscripts (50% v 17%; P = 0.023) and data analysis (63% v 23%; P = 0.002). People with primary school children more frequently reported reduced productivity in writing manuscripts (42% v 16%; P = 0.026) and generating new ideas (43% v 19%; P = 0.030). On a positive note, the presence of children in the home was not associated with changes in mental health during the pandemic. In contrast to established researchers, early career researchers frequently reported reduced productivity while working at home. CONCLUSIONS: Our findings are probably applicable to scientists in other countries. They may help improve work-from-home policies by removing the stigma associated with pyjama wearing during work and by providing support for working parents and early career researchers.


Assuntos
COVID-19 , Eficiência Organizacional/estatística & dados numéricos , Pessoal de Saúde/estatística & dados numéricos , Saúde Mental/estatística & dados numéricos , Teletrabalho , Adolescente , Adulto , Austrália , Feminino , Pessoal de Saúde/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Prospectivos , SARS-CoV-2 , Local de Trabalho , Adulto Jovem
18.
Respirology ; 25(8): 827-835, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32026586

RESUMO

BACKGROUND AND OBJECTIVE: Abnormal peripheral airway function is an important feature of asthma and relates to asthma symptoms and poor asthma control. We aimed to determine whether peripheral airway function, as measured by forced oscillatory impedance and multiple-breath nitrogen washout (MBNW), relates to symptom improvement in asthmatic participants with uncontrolled asthma, after stepping up to high-dose ICS/LABA treatment. METHODS: A total of 19 subjects (14 females, mean age: 29.9 ± 13.6 years) with uncontrolled asthma, as defined by an ACQ5 > 1.5, taking 500 µg/day fluticasone equivalent or less, underwent spirometry, plethysmography, fractional exhaled FeNO, forced oscillatory resistance (Rrs5Hz ) and reactance (Xrs5Hz ), and indices of MBNW ventilation heterogeneity (lung clearance index (LCI), diffusion-convection-dependent (Sacin) and convection-dependent (Scond)). Measurements were made before and after 8 weeks of treatment with fluticasone/formoterol combination inhaler 250/10 µg, 2 puffs twice daily. RESULTS: Treatment improved ACQ5 (P = 0.0002), FEV1 (P = 0.02), FVC (P = 0.04), FeNO (P = 0.0008), Xrs5Hz (P = 0.01), LCI (P = 0.0002), Sacin (P = 0.006) and Scond (P = 0.01). At baseline, ACQ5 correlated with Xrs5Hz (rs = 0.52, P = 0.03) and Rrs5Hz (rs = 0.55, P = 0.02). The improvement in ACQ5 was predicted by more abnormal baseline LCI (P = 0.03), Scond (P = 0.02) and Rrs5Hz (P = 0.006). Baseline Scond was the best predictor of a clinically meaningful improvement in asthma control (ΔACQ > 0.5, ROC-AUC = 0.91, P = 0.007). CONCLUSION: Step-up to high-dose combination treatment in uncontrolled asthma is associated with improved peripheral airway function as measured by Xrs5Hz and MBNW. Baseline MBNW and FOT parameters correlated with the improvement in symptoms and may predict a positive response to up-titration in uncontrolled asthmatic patients.


Assuntos
Asma/tratamento farmacológico , Asma/prevenção & controle , Oscilometria , Ventilação Pulmonar , Administração por Inalação , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Adulto , Asma/fisiopatologia , Combinação de Medicamentos , Feminino , Fluticasona/administração & dosagem , Fluticasona/farmacologia , Fluticasona/uso terapêutico , Fumarato de Formoterol/administração & dosagem , Fumarato de Formoterol/farmacologia , Fumarato de Formoterol/uso terapêutico , Humanos , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Masculino , Nitrogênio/metabolismo , Ventilação Pulmonar/efeitos dos fármacos , Curva ROC , Respiração , Testes de Função Respiratória , Espirometria
19.
Respirology ; 25(6): 613-619, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31482693

RESUMO

BACKGROUND AND OBJECTIVE: Fixed airflow obstruction (FAO) in asthma occurs despite optimal inhaled treatment and no smoking history, and remains a significant problem, particularly with increasing age and duration of asthma. Increased lung compliance and loss of lung elastic recoil has been observed in older people with asthma, but their link to FAO has not been established. We determined the relationship between abnormal lung elasticity and airflow obstruction in asthma. METHODS: Non-smoking asthmatic subjects aged >40 years, treated with 2 months of high-dose inhaled corticosteroid/long-acting beta-agonist (ICS/LABA), had FAO measured by spirometry, and respiratory system resistance at 5 Hz (Rrs5 ) and respiratory system reactance at 5 Hz (Xrs5 ) measured by forced oscillation technique. Lung compliance (K) and elastic recoil (B/A) were calculated from pressure-volume curves measured by an oesophageal balloon. Linear correlations between K and B/A, and forced expiratory volume in 1 s/forced vital capacity (FEV1 /FVC), Rrs5 and Xrs5 were assessed. RESULTS: Eighteen subjects (11 males; mean ± SD age: 64 ± 8 years, asthma duration: 39 ± 22 years) had moderate FAO measured by spirometry ((mean ± SD z-score) post-bronchodilator FEV1 : -2.2 ± 0.5, FVC: -0.7 ± 1.0, FEV1 /FVC: -2.6 ± 0.7) and by increased Rrs5 (median (IQR) z-score) 2.7 (1.9 to 3.2) and decreased Xrs5 : -4.1(-2.4 to -7.3). Lung compliance (K) was increased in 9 of 18 subjects and lung elastic recoil (B/A) reduced in 5 of 18 subjects. FEV1 /FVC correlated negatively with K (rs = -0.60, P = 0.008) and Rrs5 correlated negatively with B/A (rs = -0.52, P = 0.026), independent of age. Xrs5 did not correlate with lung elasticity indices. CONCLUSION: Increased lung compliance and loss of elastic recoil relate to airflow obstruction in older non-smoking asthmatic subjects, independent of ageing. Thus, structural lung tissue changes may contribute to persistent, steroid-resistant airflow obstruction. CLINICAL TRIAL REGISTRATION: ACTRN126150000985583 at anzctr.org.au (UTN: U1111-1156-2795).


Assuntos
Corticosteroides/uso terapêutico , Asma/tratamento farmacológico , Volume Expiratório Forçado/fisiologia , Complacência Pulmonar/fisiologia , Capacidade Vital/fisiologia , Idoso , Asma/patologia , Elasticidade/efeitos dos fármacos , Feminino , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica , Testes de Função Respiratória/métodos , Espirometria/métodos
20.
Respirology ; 25(10): 1082-1089, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32713105

RESUMO

The TSANZ develops position statements where insufficient data exist to write formal clinical guidelines. In 2018, the TSANZ addressed the question of potential benefits and health impacts of electronic cigarettes (EC). The working party included groups focused on health impacts, smoking cessation, youth issues and priority populations. The 2018 report on the Public Health Consequences of E-Cigarettes from the United States NASEM was accepted as reflective of evidence to mid-2017. A search for papers subsequently published in peer-reviewed journals was conducted in August 2018. A small number of robust and important papers published until March 2019 were also identified and included. Groups identified studies that extended, modified or contradicted the NASEM report. A total of 3793 papers were identified and reviewed, with summaries and draft position statements developed and presented to TSANZ membership in April 2019. After feedback from members and external reviewers, a collection of position statements was finalized in December 2019. EC have adverse lung effects and harmful effects of long-term use are unknown. EC are unsuitable consumer products for recreational use, part-substitution for smoking or long-term exclusive use by former smokers. Smokers who require support to quit smoking should be directed towards approved medication in conjunction with behavioural support as having the strongest evidence for efficacy and safety. No specific EC product can be recommended as effective and safe for smoking cessation. Smoking cessation claims in relation to EC should be assessed by established regulators.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Sociedades Médicas , Adolescente , Adulto , Austrália , Feminino , Humanos , Masculino , Nova Zelândia , Saúde Pública , Fatores de Risco , Fumar/efeitos adversos , Abandono do Hábito de Fumar , Fumar Tabaco , Estados Unidos
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