It is increasingly recognized that the ubiquity of convenient single-use plastic has resulted in a global plastic pollution challenge, with substantial environmental and health consequences. ...Physical, chemical, and biological processes result in plastic weathering, with eventual formation of debris in the micro to nano size range. There is an increasing awareness that plastic fragments are dispersed in the air and can be inhaled by humans, which may cause adverse effects on the respiratory system and on other systems. Urban environments are often characterized by high concentrations of fine airborne dust from various sources. To date, however, there is limited information on the distribution, shape, and size of microplastics in the air in urban and other environments. In this article, we review and discuss our current understanding of the exposure characteristics of airborne plastic debris in urbanized areas, focusing on concentration, size, morphology, presence of additives and distributions of different polymers. The natural and extend data are compiled and compared to laboratory-based analyses to further our understanding of the potential adverse effects of inhaled plastic particles on human health.
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•Plastic fragments are dispersed in air, and can be inhaled.•There is limited information on the distribution of microplastics in air samples.•They may cause adverse effects on the respiratory system and beyond.•The exposure risk of inhaled MPs for human (respiratory) health is unresolved.
Severe COVID-19 patients develop acute respiratory distress syndrome that may progress to cytokine storm syndrome, organ dysfunction, and death. Considering that neutrophil extracellular traps (NETs) ...have been described as important mediators of tissue damage in inflammatory diseases, we investigated whether NETs would be involved in COVID-19 pathophysiology. A cohort of 32 hospitalized patients with a confirmed diagnosis of COVID-19 and healthy controls were enrolled. The concentration of NETs was augmented in plasma, tracheal aspirate, and lung autopsies tissues from COVID-19 patients, and their neutrophils released higher levels of NETs. Notably, we found that viable SARS-CoV-2 can directly induce the release of NETs by healthy neutrophils. Mechanistically, NETs triggered by SARS-CoV-2 depend on angiotensin-converting enzyme 2, serine protease, virus replication, and PAD-4. Finally, NETs released by SARS-CoV-2-activated neutrophils promote lung epithelial cell death in vitro. These results unravel a possible detrimental role of NETs in the pathophysiology of COVID-19. Therefore, the inhibition of NETs represents a potential therapeutic target for COVID-19.
Plastics are widely used by society, and their degradation into millimetre fragments, called microplastics (MPs), has become a global environmental threat to ecosystems and human health. However, ...airborne MPs' presence and fallout fluxes from the atmosphere are poorly understood and can vary significantly by different conditions, especially in megacities of low- and middle-income countries, where high levels of vehicular air pollution, a high-density population, high plastic use, and inadequate disposal are environmental threats related to airborne MPs. In this study, we investigate the amount, chemical composition, and morphological characteristics of outdoor and indoor airborne MPs fallout in the megacity of São Paulo and assess the influence of weather and seasons on airborne MPs fallout. The results were as follows: MPs were found in all samples with an average fallout rate of 309.40 ± 214.71 MPs/m2/day in the indoor environment, and 123.20 ± 47.09 MPs/m2/day in the outdoor environment; MPs concentrations were higher in the indoor environment than the outdoor environment, with more fibres than particles; polyester fibres (100%), polyethylene (59%) and polypropylene (26%) particles were the dominant polymers indoors, while in outdoors, polyester fibres (76%) and polyethylene (67%) and polyethylene terephthalate (25%) particles were dominant. Fragment was the dominant morphology of particles found in indoor and outdoor samples (64% and 74%, respectively). Outdoor MPs fallout correlated positively with rainfall, wind velocity, and relative humidity. This evidence is the first on airborne MPs in a Latin America megacity and highlights the relevant role that this source plays in different environments.
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•Airborne MPs are present in outdoor and indoor environments in São Paulo.•Our data showed a higher concentration of MPs in the indoor than the outdoor.•Fibres predominated over particles in the collected samples.•Outdoor MPs fallout was influenced by rainfall, wind velocity and relative humidity.
Severe or therapy-resistant asthma is increasingly recognised as a major unmet need. A Task Force, supported by the European Respiratory Society and American Thoracic Society, reviewed the definition ...and provided recommendations and guidelines on the evaluation and treatment of severe asthma in children and adults. A literature review was performed, followed by discussion by an expert committee according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach for development of specific clinical recommendations. When the diagnosis of asthma is confirmed and comorbidities addressed, severe asthma is defined as asthma that requires treatment with high dose inhaled corticosteroids plus a second controller and/or systemic corticosteroids to prevent it from becoming "uncontrolled" or that remains "uncontrolled" despite this therapy. Severe asthma is a heterogeneous condition consisting of phenotypes such as eosinophilic asthma. Specific recommendations on the use of sputum eosinophil count and exhaled nitric oxide to guide therapy, as well as treatment with anti-IgE antibody, methotrexate, macrolide antibiotics, antifungal agents and bronchial thermoplasty are provided. Coordinated research efforts for improved phenotyping will provide safe and effective biomarker-driven approaches to severe asthma therapy.
Background Severe asthma might be associated with overexpression of T h 17 cytokines, which induce neutrophil recruitment via neutrophil-mobilizing cytokines in airways. Objective To study ...IL-17–related cytokines in nasal/bronchial biopsies from controls and mild asthmatics (MAs) to severe asthmatics (SAs) in relation to exacerbation rate. Methods Inflammatory cells and IL-17A+ , IL-17F+ , IL-21+ , IL-22+ , and IL-23+ cells were examined by immunohistochemistry in cryostat sections of bronchial/nasal biopsies obtained from 33 SAs (21 frequent exacerbators FEs), 31 MAs (3 FEs), and 14 controls. IL-17F protein was also measured by ELISA in bronchial/nasal lysates and by immunohistochemistry in bronchial tissue obtained from subjects who died because of fatal asthma. Immunofluorescence/confocal microscopy was used for IL-17F colocalization. Results Higher number ( P < .05) of neutrophils, IL-17A+ , IL-17F+ , and IL-21+ cells in bronchial biopsies and higher numbers ( P < .01) of IL-17F+ and IL-21+ cells in nasal biopsies were observed in SAs compared with MAs. Bronchial IL-17F+ cells correlated with bronchial neutrophils ( r = 0.54), exacerbation rate ( r = 0.41), and FEV1 ( r = −0.46). Nasal IL-17F+ cells correlated with bronchial IL-17F ( r = 0.35), exacerbation rate ( r = 0.47), and FEV1 ( r = −0.61). FEs showed increased number of bronchial neutrophils/eosinophils/CD4+ /CD8+ cells and bronchial/nasal IL-17F+ cells. Receiver operating characteristic curve analysis evidenced predictive cutoff values of bronchial neutrophils and nasal/bronchial IL-17F for discriminating between asthmatics and controls, between MAs and SAs and between FEs and non-FEs. IL-17F protein increased in bronchial/nasal lysates of SAs and FEs and in bronchial tissue of fatal asthma. IL-17F colocalized in CD4+ /CD8+ cells. Conclusions IL-17–related cytokines expression was amplified in bronchial/nasal mucosa of neutrophilic asthma prone to exacerbation, suggesting a pathogenic role of IL-17F in FEs.
Autopsy continues to play an essential role in monitoring opportunistic fungal infections. However, few studies have analysed the historical trends of fungal infections in autopsies. Here, we analyse ...available data on fungal infections obtained from autopsy reports during 85 years of autopsies performed by the largest autopsy service in Brazil. All invasive fungal infections presented in autopsy reports between 1930 and 2015 were included. Of the 158,404 autopsy reports analysed, 1096 involved invasive fungal infections. In general, paracoccidioidomycosis (24%) was the most frequent infection, followed by candidiasis (18%), pneumocystosis (11.7%), cryptococcosis (11%), aspergillosis (11%) and histoplasmosis (3.8%). Paracoccidioidomycosis decreased after the 1950s, whereas opportunistic fungal infections increased steadily after the 1980s during the peak of the AIDS pandemic. The lung was the most frequently affected organ (73%). Disseminated infection was present in 64.5% of cases. In 26% of the 513 cases for which clinical charts were available for review, the diagnosis of opportunistic fungal infections was performed only at autopsy. Our unique 85-year history of autopsies showed a transition from endemic to opportunistic fungal infections in São Paulo, Brazil, reflecting increased urbanization, the appearance of novel diseases, such as AIDS in the 1980s, and advances in medical care over time.
Increased thickness of the airway smooth muscle (ASM) layer in asthma may result from hyperplasia or hypertrophy of muscle cells or increased extracellular matrix (ECM).
To relate ASM hypertrophy, ...ASM hyperplasia, and deposition of ECM to the severity and duration of asthma.
Airways from control subjects (n = 51) and from cases of nonfatal (n = 49) and fatal (n = 55) asthma were examined postmortem. Mean ASM cell volume (V(C)), the number of ASM cells per length of airway (N(L)), and the volume fraction of extracellular matrix (f(ECM)) within the ASM layer were estimated. Comparisons between subject groups were made on the basis of general linear regression models.
Mean V(C) was increased in the large airways of cases of nonfatal asthma (P = 0.015) and fatal asthma (P < 0.001) compared with control subjects. N(L) was similar in nonfatal cases and control subjects but increased in large (P < 0.001), medium (P < 0.001), and small (P = 0.034) airways of cases of fatal asthma compared with control subjects and with nonfatal cases (large and medium airways, P ≤ 0.003). The f(ECM) was similar in cases of asthma and control subjects. Duration of asthma was associated with a small increase in N(L).
Hypertrophy of ASM cells occurs in the large airways in both nonfatal and fatal cases of asthma, but hyperplasia of ASM cells is present in the large and small airways in fatal asthma cases only. Both are associated with an absolute increase in ECM. Duration of asthma has little or no effect on ASM hypertrophy or hyperplasia or f(ECM).
Purpose
This study was designed to evaluate the usefulness of lung ultrasound (LUS) imaging to characterize the progression and severity of lung damage in cases of COVID-19.
Methods
We employed a set ...of combined ultrasound parameters and histopathological images obtained simultaneously in 28 patients (15 women, 0.6–83 years) with fatal COVID-19 submitted to minimally invasive autopsies, with different times of disease evolution from initial symptoms to death (3–37 days, median 18 days). For each patient, we analysed eight post-mortem LUS parameters and the proportion of three histological patterns (normal lung, exudative diffuse alveolar damage DAD and fibroproliferative DAD) in eight different lung regions. The relationship between histopathological and post-mortem ultrasonographic findings was assessed using various statistical approaches.
Results
Statistically significant positive correlations were observed between fibroproliferative DAD and peripheral consolidation (coefficient 0.43,
p
= 0.02) and pulmonary consolidation (coefficient 0.51,
p
= 0.005). A model combining age, time of evolution, sex and ultrasound score predicted reasonably well (
r
= 0.66) the proportion of pulmonary parenchyma with fibroproliferative DAD.
Conclusion
The present study adds information to previous studies related to the use of LUS as a tool to assess the severity of acute pulmonary damage. We provide a histological background that supports the concept that LUS can be used to characterize the progression and severity of lung damage in severe COVID-19.
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