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BACKGROUND: Clinical trial satisfaction is increasingly important for future trial designs and is associated with treatment adherence and willingness to enroll in future research studies or to recommend trial participation. In this post-trial survey, we examined participant satisfaction and attitudes toward future clinical trials in the Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU). METHODS: We developed an anonymous, participant satisfaction survey tailored to participants enrolled in the DIAN-TU-001 double-blind clinical trial of solanezumab or gantenerumab and requested that all study sites share the survey with their trial participants. A total of 194 participants enrolled in the trial at 24 study sites. We utilized regression analysis to explore the link between participants' clinical trial experiences, their satisfaction, and their willingness to participate in upcoming trials. RESULTS: Survey responses were received over a sixteen-month window during 2020-2021 from 58 participants representing 15 study sites. Notably, 96.5% of the survey respondents expressed high levels of satisfaction with the trial, 91.4% would recommend trial participation, and 96.5% were willing to enroll again. Age, gender, and education did not influence satisfaction levels. Participants reported enhanced medical care (70.7%) and pride in contributing to the DIAN-TU trial (84.5%). Satisfaction with personnel and procedures was high (98.3%). Respondents had a mean age of 48.7 years, with most being from North America and Western Europe, matching the trial's demographic distribution. Participants' decisions to learn their genetic status increased during the trial, and most participants endorsed considering future trial participation regardless of the DIAN-TU-001 trial outcome. CONCLUSION: Results suggest that DIAN-TU-001 participants who responded to the survey exhibited high motivation to participate in research, overall satisfaction with the clinical trial, and willingness to participate in research in the future, despite a long trial duration of 4-7 years with detailed annual clinical, cognitive, PET, MRI, and lumbar puncture assessments. Implementation of features that alleviate barriers and challenges to trial participation is like to have a high impact on trial satisfaction and reduce participant burden.
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Doença de Alzheimer , Anticorpos Monoclonais Humanizados , Satisfação do Paciente , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/psicologia , Masculino , Feminino , Pessoa de Meia-Idade , Anticorpos Monoclonais Humanizados/uso terapêutico , Método Duplo-Cego , Adulto , Inquéritos e Questionários , Ensaios Clínicos como AssuntoRESUMO
Large-scale production and waste of plastic materials have resulted in widespread environmental contamination by the breakdown product of bulk plastic materials to micro- and nanoplastics (MNPs). The small size of these particles enables their suspension in the air, making pulmonary exposure inevitable. Previous work has demonstrated that xenobiotic pulmonary exposure to nanoparticles during gestation leads to maternal vascular impairments, as well as cardiovascular dysfunction within the fetus. Few studies have assessed the toxicological consequences of maternal nanoplastic (NP) exposure; therefore, the objective of this study was to assess maternal and fetal health after a single maternal pulmonary exposure to polystyrene NP in late gestation. We hypothesized that this acute exposure would impair maternal and fetal cardiovascular function. Pregnant rats were exposed to nanopolystyrene on gestational day 19 via intratracheal instillation. 24 h later, maternal and fetal health outcomes were evaluated. Cardiovascular function was assessed in dams using vascular myography ex vivo and in fetuses in vivo function was measured via ultrasound. Both fetal and placental weight were reduced after maternal exposure to nanopolystyrene. Increased heart weight and vascular dysfunction in the aorta were evident in exposed dams. Maternal exposure led to vascular dysfunction in the radial artery of the uterus, a resistance vessel that controls blood flow to the fetoplacental compartment. Function of the fetal heart, fetal aorta, and umbilical artery after gestational exposure was dysregulated. Taken together, these data suggest that exposure to NPs negatively impacts maternal and fetal health, highlighting the concern of MNPs exposure on pregnancy and fetal development.
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Exposição Materna , Poliestirenos , Animais , Gravidez , Feminino , Poliestirenos/toxicidade , Exposição Materna/efeitos adversos , Nanopartículas/toxicidade , Ratos Sprague-Dawley , Pulmão/efeitos dos fármacos , Pulmão/irrigação sanguínea , Ratos , Feto/efeitos dos fármacos , Troca Materno-Fetal , Exposição por Inalação/efeitos adversos , Placenta/efeitos dos fármacos , Placenta/irrigação sanguíneaRESUMO
Glial-cell line derived neurotrophic factor (GDNF) bound to its co-receptor GFRα1 stimulates the RET receptor tyrosine kinase, promoting neuronal survival and neuroprotection. The GDNF-GFRα1 complex also supports synaptic cell adhesion independently of RET. Here, we describe the structure of a decameric GDNF-GFRα1 assembly determined by crystallography and electron microscopy, revealing two GFRα1 pentamers bridged by five GDNF dimers. We reconsitituted the assembly between adhering liposomes and used cryo-electron tomography to visualize how the complex fulfils its membrane adhesion function. The GFRα1:GFRα1 pentameric interface was further validated both in vitro by native PAGE and in cellulo by cell-clustering and dendritic spine assays. Finally, we provide biochemical and cell-based evidence that RET and heparan sulfate cooperate to prevent assembly of the adhesion complex by competing for the adhesion interface. Our results provide a mechanistic framework to understand GDNF-driven cell adhesion, its relationship to trophic signalling, and the central role played by GFRα1.
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Fator Neurotrófico Derivado de Linhagem de Célula Glial , Proteínas Proto-Oncogênicas c-ret , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transdução de SinaisRESUMO
The increasing production of intentional and unintentional nanoparticles (NPs) has led to their accumulation in the environment as air and ground pollution. The heterogeneity of these particles primarily relies on the NP physicochemical properties (i.e., chemical composition, size, shape, surface chemistry, etc.). Pregnancy represents a vulnerable life stage for both the woman and the developing fetus. The ubiquitous nature of these NPs creates a concern for developmental fetal exposures. At the maternal-fetal interface lies the placenta, a temporary endocrine organ that facilitates nutrient and waste exchange as well as communication between maternal and fetal tissues. Recent evidence in human and animal models identifies that gestational exposure to NPs results in placental translocation leading to local effects and endocrine disruption. Currently, the mechanisms underlying placental translocation and cellular uptake of NPs in the placenta are poorly understood. The purpose of this review is to assess the current understanding of the physiochemical factors influencing NP translocation, cellular uptake, and endocrine disruption at the maternal-fetal interface within the available literature.
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Nowadays, vast amounts of data representing feed intake, growth, and environmental impact of individual animals are being recorded in on-farm settings. Despite their apparent use, data collected in real-world applications often have missing values in one or several variables, due to reasons including human error, machine error, or sampling frequency misalignment across multiple variables. Since incomplete datasets are less valuable for downstream data analysis, it is important to address the missing value problem properly. One option may be to reduce the dataset to a subset that contains only complete data, but considerable data may be lost via this process. The current study aimed to compare imputation methods for the estimation of missing values in a raw dataset of dairy cattle including 454 553 records collected from 629 cows between 2009 and 2020. The dataset was subjected to a cleaning process that reduced its size to 437 075 observations corresponding to 512 cows. Missing values were present in four variables: concentrate DM intake (CDMI, missing percentage = 2.30%), forage DM intake (FDMI, 8.05%), milk yield (MY, 15.12%), and BW (64.33%). After removing all missing values, the resulting dataset (n = 129 353) was randomly sampled five times to create five independent subsets that exhibit the same missing data percentages as the cleaned dataset. Four univariate and nine multivariate imputation methods (eight machine learning methods and the MissForest method) were applied and evaluated on the five repeats, and average imputation performance was reported for each repeat. The results showed that Random Forest was overall the best imputation method for this type of data and had a lower mean squared prediction error and higher concordance correlation coefficient than the other imputation methods for all imputed variables. Random Forest performed particularly well for imputing CDMI, MY, and BW, compared to imputing FDMI.
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Leite , Projetos de Pesquisa , Humanos , Feminino , Bovinos , Animais , Aprendizado de Máquina , Ingestão de Alimentos , FazendasRESUMO
Within poultry production systems, models have provided vital decision support, opportunity analysis, and performance optimization capabilities to nutritionists and producers for decades. In recent years, due to the advancement of digital and sensor technologies, 'Big Data' streams have emerged, optimally positioned to be analyzed by machine-learning (ML) modeling approaches, with strengths in forecasting and prediction. This review explores the evolution of empirical and mechanistic models in poultry production systems, and how these models may interact with new digital tools and technologies. This review will also examine the emergence of ML and Big Data in the poultry production sector, and the emergence of precision feeding and automation of poultry production systems. There are several promising directions for the field, including: (1) application of Big Data analytics (e.g., sensor-based technologies, precision feeding systems) and ML methodologies (e.g., unsupervised and supervised learning algorithms) to feed more precisely to production targets given a 'known' individual animal, and (2) combination and hybridization of data-driven and mechanistic modeling approaches to bridge decision support with improved forecasting capabilities.
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Big Data , Aves Domésticas , Animais , Aprendizado de Máquina , Algoritmos , TecnologiaRESUMO
The delivery of therapeutics across the cell membrane and into the cytoplasm is a major challenge that limits the development of new therapies. This challenge is compounded by the lack of a general assay for cytosolic delivery. Here we develop this assay based on the pro-fluorophore CrAsH-EDT2, and provide cytosolic penetration results for a variety of drug delivery agents (polyethyleneimine, poly-arginine, Ferritin, poly [maleic anhydride-alt-isobutene] grafted with dodecylamine, and cationic liposomes) into HeLa and T98G cells. Our results show that this method can be widely applicable to different cells and drug delivery agents, and yield statistically robust results. We later use this method to optimize and improve a model drug delivery agent's (Ferritin) cytosolic penetration.
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Portadores de Fármacos , Sistemas de Liberação de Fármacos por Nanopartículas , Preparações Farmacêuticas , Portadores de Fármacos/química , Humanos , Células HeLaRESUMO
Due to morphological convergence and the application of numerous taxonomic concepts, the systematics of filamentous cyanobacteria is still a significant problem. The incorporation and integration of modern molecular, cyto-morphological and ecological approaches in cyanobacterial taxonomy are essential and must be acknowledged as the valid methods for the development of their modern systematics. In this study, method of using 16S rRNA gene sequences to infer the genetic relationships of twelve freshwater cyanobacterial isolates amongst themselves was evaluated. The taxonomic resolution was inferred from their phylogenetic tree, in silico restriction digestion analysis and secondary structure prediction. These methods allowed cyanobacterial genera to be well distinguished with their genotypic and phenotypic differences. Amongst twelve strains, Spirulina subsalsa with highest protein content was used in this study for evaluating the stability of Curcumin which is a curcuminoid compound reported from Curcuma longa. Though they have wide properties, they still lack stability and bioavailability. It is reported previously that microbes are used for biotransformation and act as a carrier molecule. Therefore, in this study, Spirulina incorporated with curcumin resulted with pH stability of curcumin and were found to have a biotransformation into Calebin-A, curcuminoid compound originally present in smaller amount (0.005%) in C. longa with various biomedical applications.
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Curcumina , Spirulina , Spirulina/genética , RNA Ribossômico 16S/genética , FilogeniaRESUMO
Computed tomography (CT) scanning is the imaging modality of choice when planning the overall management and operative approach to complex abdominal wall hernias. Despite its availability and well-recognised benefits there are no guidelines or recommendations regarding how best to read or report such scans for this application. In this paper we aim to outline an approach to interpreting preoperative CT scans in abdominal wall reconstruction (AWR). This approach breaks up the interpretive process into 4 steps-concentrating on the hernia or hernias, any complicating features of the hernia(s), the surrounding soft tissues and the abdominopelvic cavity as a whole-and was developed as a distillation of the authors' collective experience. We describe the key features that should be looked for at each of the four steps and the rationale for their inclusion.
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Parede Abdominal , Hérnia Ventral , Hérnia Incisional , Cirurgia Plástica , Humanos , Parede Abdominal/cirurgia , Hérnia Ventral/cirurgia , Hérnia Incisional/cirurgia , Herniorrafia/métodos , Tomografia Computadorizada por Raios X/métodosRESUMO
Complex abdominal wall reconstruction is an emerging subspecialty yet, despite the abundance of abdominal wall hernias requiring treatment and the increasing complexity of this type of surgery, there are few opportunities for surgeons to gain subspecialist training in this field. In this paper we discuss the need for focused training in complex abdominal wall reconstruction, outline some of the problems that may be hindering the availability of such opportunities and propose potential solutions to these issues.
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Tendon function is dependent on proper organization and maintenance of the collagen I tissue matrix. Collagen V is a critical regulator of collagen I fibrils, and while prior studies have shown a negative impact of collagen V deficiency on tendon healing outcomes, these studies are confounded by collagen V deficiency through tendon development. The specific role of collagen V in regulating healing tendon properties is therefore unknown. By using inducible Col5a1 knockdown models and analyzing gene expression, fibril and histological tendon morphology, and tendon mechanical properties, this study defines the isolated role of collagen V through tendon healing. Patellar tendon injury caused large changes in tendon gene expression, and Col5a1 knockdown resulted in dysregulated expression of several genes through tendon healing. Col5a1 knockdown also impacted collagen fibril size and shape without observable changes in scar tissue formation. Surprisingly, heterozygous Col5a1 knockdown resulted in improved stiffness of healing tendons that was not observed with homozygous Col5a1 knockdown. Together, these results present an unexpected and dynamic role of collagen V deficiency on tendon healing outcomes following injury. This work suggests a model of tendon healing in which quasi-static mechanics may be improved through titration of collagen fibril size and shape with modulation of collagen V expression and activity.
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Ligamento Patelar , Traumatismos dos Tendões , Camundongos , Animais , Fenômenos Biomecânicos , Tendões/metabolismo , Colágeno/metabolismo , Traumatismos dos Tendões/metabolismo , Colágeno Tipo I/genéticaRESUMO
Hydatid disease involving multiple organs is rare in clinical practice. The most commonly affected organs in adults include the liver and lungs. We report a case of a 54-year-old woman who presented to our hospital with multiple cystic lesions in the liver, lung and spleen. The case highlights the need to have a high index of suspicion for hydatid disease in endemic areas in patients with this clinical presentation.
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PURPOSE: There are no universally agreed guidelines regarding which types of physical activity are safe and/or recommended in the perioperative period for patients undergoing ventral hernia repair or abdominal wall reconstruction (AWR). This study is intended to identify and summarise the literature on this topic. METHODS: Database searches of PubMed, CINAHL, Allied & Complementary medicine database, PEDro and Web of Science were performed followed by a snowballing search using two papers identified by the database search and four hand-selected papers of the authors' choosing. Inclusion-cohort studies, randomized controlled trials, prospective or retrospective. Studies concerning complex incisional hernia repairs and AWRs including a "prehabilitation" and/or "rehabilitation" program targeting the abdominal wall muscles in which the interventions were of a physical exercise nature. RoB2 and Robins-I were used to assess risk of bias. Prospero CRD42021236745. No external funding. Data from the included studies were extracted using a table based on the Cochrane Consumers and Communication Review Group's data extraction template. RESULTS: The database search yielded 5423 records. After screening two titles were selected for inclusion in our study. The snowballing search identified 49 records. After screening one title was selected for inclusion in our study. Three total papers were included-two randomised studies and one cohort study (combined 423 patients). All three studies subjected their patients to varying types of physical activity preoperatively, one study also prescribed these activities postoperatively. The outcomes differed between the studies therefore meta-analysis was impossible-two studies measured hernia recurrence, one measured peak torque. All three studies showed improved outcomes in their study groups compared to controls however significant methodological flaws and confounding factors existed in all three studies. No adverse events were reported. CONCLUSIONS: The literature supporting the advice given to patients regarding recommended physical activity levels in the perioperative period for AWR patients is sparse. Further research is urgently required on this subject.
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Parede Abdominal , Hérnia Ventral , Parede Abdominal/cirurgia , Estudos de Coortes , Exercício Físico , Hérnia Ventral/cirurgia , Herniorrafia , Humanos , Estudos Prospectivos , Estudos RetrospectivosRESUMO
Prader-Willi Syndrome (PWS) is a multi-system genetically determined neurodevelopmental disorder and the commonest cause of syndromal obesity. The development of hyperphagia in early childhood is part of the phenotype arising as a result of an impaired neural response to food intake and the inability to regulate food intake in line with energy needs. Severe obesity develops if access to food is not controlled. In this review we evaluate the evidence for increased morbidity and mortality in PWS in order to establish the extent to which it is directly related to the obesity; a consequence of the eating behaviour itself independent of obesity; or associated with other characteristics of the syndrome. Medline, Cochrane, PsychINFO, CINAHL, Web of Science and Scopus databases were used to systematically identify published material on PWS and hyperphagia and syndrome-related morbidity and mortality. One hundred and ten key papers were selected. Data on 500 people with PWS indicated that the average age of death was 21 years and obesity was, as expected, a significant factor. However, the behaviour of hyperphagia itself, independent of obesity, was also important, associated with choking, gastric rupture, and/or respiratory illness. Other syndrome-related factors increased the risk for, and seriousness of, co-morbid illness or accidents. We conclude that improving life-expectancy largely depends on managing the immediate non-obesity and obesity-related consequences of the hyperphagia, through improved support. The development of new treatments that significantly reduce the drive to eat are likely to decrease morbidity and mortality improving quality of life and life expectancy.
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Hiperfagia/epidemiologia , Síndrome de Prader-Willi/epidemiologia , Humanos , Hiperfagia/terapia , Morbidade , Síndrome de Prader-Willi/terapiaRESUMO
INTRODUCTION: Laparoscopy is used in as many as 95% of adult appendicectomies. There is level I evidence showing that it reduces wound infection, postoperative ileus and length of inpatient stay in children compared with the open approach. The aim of this study was to report the uptake of laparoscopy for paediatric appendicectomy in England and to determine whether this was similar for general surgeons (GS) and specialist paediatric surgeons (SPS). METHODS: Hospital Episode Statistics data were obtained for all children aged <16 years who had an OPCS 4.6 code for emergency appendicectomy from 1997 to 2015 (18 years). Data are analysed to compare rate of laparoscopic vs open procedures for GS and SPS over time and to investigate factors associated with the use of laparoscopy. RESULTS: There were 196,987 appendicectomies and where specialty was available, 133,709 (79%) cases were undertaken by GS and 35,141 (21%) by SPS. The rate of cases undertaken with laparoscopy for both specialties combined increased from 0.8% in 1998 to 50% in 2014 (p<0.0001). In 2014, this rate was 41% for GS compared with 71% for SPS (p<0.0001). Female gender (odds ratio (OR)=1.84, 95% confidence interval (CI) 1.80-1.90), increasing age (OR=1.18, 95% CI 1.18-1.19 per year) and treatment by SPS (OR=3.71, 95% CI 3.60-3.82) were all factors positively associated with use of laparoscopy in multivariate analysis. CONCLUSIONS: There has been a vast increase in the proportion of appendicectomies undertaken laparoscopically in children. Despite adjusting for patient factors, laparoscopy was used significantly less by GS when compared with SPS. This difference is most apparent in younger children.
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Apendicite , Laparoscopia , Cirurgiões , Adulto , Apendicectomia/métodos , Apendicite/cirurgia , Criança , Inglaterra/epidemiologia , Feminino , Humanos , Laparoscopia/métodos , Tempo de Internação , Estudos RetrospectivosRESUMO
Novel species of fungi described in this study include those from various countries as follows: Australia, Agaricus albofoetidus, Agaricus aureoelephanti and Agaricus parviumbrus on soil, Fusarium ramsdenii from stem cankers of Araucaria cunninghamii, Keissleriella sporoboli from stem of Sporobolus natalensis, Leptosphaerulina queenslandica and Pestalotiopsis chiaroscuro from leaves of Sporobolus natalensis, Serendipita petricolae as endophyte from roots of Eriochilus petricola, Stagonospora tauntonensis from stem of Sporobolus natalensis, Teratosphaeria carnegiei from leaves of Eucalyptus grandis × E. camaldulensis and Wongia ficherai from roots of Eragrostis curvula. Canada, Lulworthia fundyensis from intertidal wood and Newbrunswickomyces abietophilus (incl. Newbrunswickomyces gen. nov.) on buds of Abies balsamea. Czech Republic, Geosmithia funiculosa from a bark beetle gallery on Ulmus minor and Neoherpotrichiella juglandicola (incl. Neoherpotrichiella gen. nov.) from wood of Juglans regia. France, Aspergillus rouenensis and Neoacrodontium gallica (incl. Neoacrodontium gen. nov.) from bore dust of Xestobium rufovillosum feeding on Quercus wood, Endoradiciella communis (incl. Endoradiciella gen. nov.) endophytic in roots of Microthlaspi perfoliatum and Entoloma simulans on soil. India, Amanita konajensis on soil and Keithomyces indicus from soil. Israel, Microascus rothbergiorum from Stylophora pistillata. Italy, Calonarius ligusticus on soil. Netherlands, Appendopyricularia juncicola (incl. Appendopyricularia gen. nov.), Eriospora juncicola and Tetraploa juncicola on dead culms of Juncus effusus, Gonatophragmium physciae on Physcia caesia and Paracosmospora physciae (incl. Paracosmospora gen. nov.) on Physcia tenella, Myrmecridium phragmitigenum on dead culm of Phragmites australis, Neochalara lolae on stems of Pteridium aquilinum, Niesslia nieuwwulvenica on dead culm of undetermined Poaceae, Nothodevriesia narthecii (incl. Nothodevriesia gen. nov.) on dead leaves of Narthecium ossifragum and Parastenospora pini (incl. Parastenospora gen. nov.) on dead twigs of Pinus sylvestris. Norway, Verticillium bjoernoeyanum from sand grains attached to a piece of driftwood on a sandy beach. Portugal, Collybiopsis cimrmanii on the base of living Quercus ilex and amongst dead leaves of Laurus and herbs. South Africa, Paraproliferophorum hyphaenes (incl. Paraproliferophorum gen. nov.) on living leaves of Hyphaene sp. and Saccothecium widdringtoniae on twigs of Widdringtonia wallichii. Spain, Cortinarius dryosalor on soil, Cyphellophora endoradicis endophytic in roots of Microthlaspi perfoliatum, Geoglossum lauri-silvae on soil, Leptographium gemmatum from fluvial sediments, Physalacria auricularioides from a dead twig of Castanea sativa, Terfezia bertae and Tuber davidlopezii in soil. Sweden, Alpova larskersii, Inocybe alpestris and Inocybe boreogodeyi on soil. Thailand, Russula banwatchanensis, Russula purpureoviridis and Russula lilacina on soil. Ukraine, Nectriella adonidis on overwintered stems of Adonis vernalis. USA, Microcyclus jacquiniae from living leaves of Jacquinia keyensis and Penicillium neoherquei from a minute mushroom sporocarp. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Boers J, Holdom D, et al. 2022. Fungal Planet description sheets: 1383-1435. Persoonia 48: 261-371. https://doi.org/10.3767/persoonia.2022.48.08.
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SUMMARY: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is transmitted mainly by aerosol in particles <10 µm that can remain suspended for hours before being inhaled. Because particulate filtering facepiece respirators ('respirators'; e.g. N95 masks) are more effective than surgical masks against bio-aerosols, many international organisations now recommend that health workers (HWs) wear a respirator when caring for individuals who may have COVID-19. In South Africa (SA), however, surgical masks are still recommended for the routine care of individuals with possible or confirmed COVID-19, with respirators reserved for so-called aerosol-generating procedures. In contrast, SA guidelines do recommend respirators for routine care of individuals with possible or confirmed tuberculosis (TB), which is also transmitted via aerosol. In health facilities in SA, distinguishing between TB and COVID-19 is challenging without examination and investigation, both of which may expose HWs to potentially infectious individuals. Symptom-based triage has limited utility in defining risk. Indeed, significant proportions of individuals with COVID-19 and/or pulmonary TB may not have symptoms and/or test negative. The prevalence of undiagnosed respiratory disease is therefore likely significant in many general clinical areas (e.g. waiting areas). Moreover, a proportion of HWs are HIV-positive and are at increased risk of severe COVID-19 and death. RECOMMENDATIONS: Sustained improvements in infection prevention and control (IPC) require reorganisation of systems to prioritise HW and patient safety. While this will take time, it is unacceptable to leave HWs exposed until such changes are made. We propose that the SA health system adopts a target of 'zero harm', aiming to eliminate transmission of respiratory pathogens to all individuals in every healthcare setting. Accordingly, we recommend: the use of respirators by all staff (clinical and non-clinical) during activities that involve contact or sharing air in indoor spaces with individuals who: (i) have not yet been clinically evaluated; or (ii) are thought or known to have TB and/or COVID-19 or other potentially harmful respiratory infections;the use of respirators that meet national and international manufacturing standards;evaluation of all respirators, at the least, by qualitative fit testing; andthe use of respirators as part of a 'package of care' in line with international IPC recommendations. We recognise that this will be challenging, not least due to global and national shortages of personal protective equipment (PPE). SA national policy around respiratory protective equipment enables a robust framework for manufacture and quality control and has been supported by local manufacturers and the Department of Trade, Industry and Competition. Respirator manufacturers should explore adaptations to improve comfort and reduce barriers to communication. Structural changes are needed urgently to improve the safety of health facilities: persistent advocacy and research around potential systems change remain essential.