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1.
Front Pediatr ; 12: 1391290, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38910961

RESUMEN

In contrast to significant declines in deaths due to lung cancer and cardiac disease in Westernised countries, the mortality due to 'chronic obstructive pulmonary disease' (COPD) has minimally changed in recent decades while 'the incidence of bronchiectasis' is on the rise. The current focus on producing guidelines for these two airway 'diseases' has hindered progress in both treatment and prevention. The elephant in the room is that neither COPD nor bronchiectasis is a disease but rather a consequence of progressive untreated airway inflammation. To make this case, it is important to review the evolution of our understanding of airway disease and how a pathological appearance (bronchiectasis) and an arbitrary physiological marker of impaired airways (COPD) came to be labelled as 'diseases'. Valuable insights into the natural history of airway disease can be obtained from the pre-antibiotic era. The dramatic impacts of antibiotics on the prevalence of significant airway disease, especially in childhood and early adult life, have largely been forgotten and will be revisited as will the misinterpretation of trials undertaken in those with chronic (bacterial) bronchitis. In the past decades, paediatricians have observed a progressive increase in what is termed 'persistent bacterial bronchitis' (PBB). This condition shares all the same characteristics as 'chronic bronchitis', which is prevalent in young children during the pre-antibiotic era. Additionally, the radiological appearance of bronchiectasis is once again becoming more common in children and, more recently, in adults. Adult physicians remain sceptical about the existence of PBB; however, in one study aimed at assessing the efficacy of antibiotics in adults with persistent symptoms, researchers discovered that the majority of patients exhibiting symptoms of PBB were already on long-term macrolides. In recent decades, there has been a growing recognition of the importance of the respiratory microbiome and an understanding of the ability of bacteria to persist in potentially hostile environments through strategies such as biofilms, intracellular communities, and persister bacteria. This is a challenging field that will likely require new approaches to diagnosis and treatment; however, it needs to be embraced if real progress is to be made.

2.
Integr Environ Assess Manag ; 20(1): 189-200, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37341039

RESUMEN

Built development changes the nature of land and its ecosystems, with diverse ramifications for human well-being and the resilience of the socioecological system. Robust and replicable approaches are required to assess ecosystem services generated by sites both predevelopment and for evaluation of postdevelopment options, to assess change and to support a paradigm shift from a "do less harm" to a "regenerative" approach. The Rapid Assessment of Wetland Ecosystem Services (RAWES) approach provides an internationally recognized methodology for systemic assessment of the ecosystem services generated by a site, taking account of all ecosystem services and service categories across multiple spatial scales. The RAWES assessments of constituent ecosystem services can be combined into Ecosystem Service Index scores. This article outlines innovations in RAWES methods to assess changes in ecosystem services likely to result from differing development scenarios in the context of a case study site in eastern England. These adaptations of the RAWES approach include revised methods for the analysis of ecosystem service beneficiaries across multiple spatial scales, the establishment of a common baseline against which to compare likely ecosystem service outcomes under a range of development scenarios, and a standardized method for accounting for supporting services through their contributions to other more directly exploited services. Integr Environ Assess Manag 2024;20:189-200. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Asunto(s)
Ecosistema , Humedales , Humanos , Monitoreo del Ambiente/métodos , Ecotoxicología
3.
Integr Environ Assess Manag ; 20(1): 248-262, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37435836

RESUMEN

The built environment, even at its "greenest," inevitably entails changing ecosystem structure and function. Multiple sustainable development tools and approaches are available to reduce environmental harm from built development. However, the reality that society exists within fully integrated socioecological systems, wholly interdependent on supporting ecosystems, is not yet adequately represented in regulation or supporting tools. Regenerative development seeks to address this interdependence in part by improving the health of supporting socioecological systems through the development process. We demonstrate the relevance of a series of approaches-Local Nature-Related Planning Policy (LNRPP), Biodiversity Net Gain (BNG), the Environmental Benefits from Nature Tool (EBN Tool), Nature Assessment Tool for Urban and Rural Environments (NATURE Tool), and Rapid Assessment of Wetland Ecosystem Services+ (RAWES+)-for their ability to meet their stated aims and objectives and how these relate to wider regenerative themes. A comparative analysis of the five approaches is done by applying them to a practical case study site, resulting in policy- and practice-relevant learning and recommendations. The research reveals current gaps in methodology, which can lead to adverse outcomes for sustainability. This is particularly clear for the spatial and temporal scales across which each approach operates. In addition, this research discusses the inherent limitations of taking a reductionist approach to examining complex systems. Integr Environ Assess Manag 2024;20:248-262. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Monitoreo del Ambiente/métodos , Biodiversidad , Ecotoxicología , Humedales , Medición de Riesgo/métodos
4.
Viral Immunol ; 36(7): 466-474, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37523237

RESUMEN

Respiratory syncytial virus (RSV) causes annual epidemics of infections affecting the whole population. In vitro, it has been shown to infect and persist in human dendritic cells (DCs) for prolonged periods. Initially persistence is associated with low levels of replication before the virus becomes dormant. Reactivation of viral replication can be triggered many months later. Infection of DCs is likely to influence the host's ability to generate effective long-term memory responses. A well-established animal was utilized to confirm that RSV both infects and persists in pulmonary DCs in vivo. Mice were infected with a modified strain of RSV expressing red fluorescent protein (RSV-RFP) when replicating. Clinical symptoms of infection were monitored using weight change and inflammatory cell counts from bronchoalveolar lavage, which correlated with the RSV viral titer (quantitative polymerase chain reaction). Lung tissues were collected at 3, 5, 7, and 21 days postinfection (dpi) to assess leukocyte populations by flow cytometry. Clinical symptoms and RSV viral load peaked at 5 dpi. RSV-RFP was most prevalent in macrophages at 3 dpi and also observed in B cells and DCs. At 21 dpi, RSV-RFP remained evident in a subset of conventional DCs (CD103+CD11b+) even though both clinical symptoms and pulmonary inflammation had resolved. These results confirm that in this well-established mouse model, RSV persists in lung conventional DCs following resolution of the acute infection. Further work is required to explore whether the virus continues with low-level replication before becoming dormant in vivo, as has been described in vitro.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Animales , Humanos , Ratones , Pulmón , Macrófagos , Células Dendríticas , Ratones Endogámicos BALB C
5.
Integr Environ Assess Manag ; 19(4): 1131-1146, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36519960

RESUMEN

Misleading conclusions can result from applying tools beyond the purposes for which they were designed. A range of chemical assessment systems was compared against a set of principles germane to the sustainable use of chemicals relevant to the whole societal life cycles of finished products. These principles of sustainable use included: wider dimensions of sustainability, a foundation in science, consideration of life-cycle risk rather than simply intrinsic chemical properties, contributions to meeting human needs, open access, and peer review. A transparent basis in science is important for deriving objective, comparable, and replicable sustainability-based findings across materials and applications, and for guiding innovation. Few assessment systems currently identify how use of substances contributes to meeting human needs, a vital albeit often overlooked aspect of sustainable development, with most based largely on potential hazard without addressing wider life-cycle exposure and risk assessment. Qualitatively differing substances were illustratively assessed against the sustainability principles and life-cycle context of the Additive Sustainability Footprint (ASF), aspects of this analysis highlighting how differing material sourcing, manufacturing, and management in-use and at end-of-life can lead to widely divergent sustainability assessments. These illustrative ASF assessments also demonstrate that material use challenges, assessed on a systemic basis, are common across materials, with no defensible automatic assumption that there are inherently "good" or "bad" materials; differing stewardship across whole product life cycles substantially influences sustainability credentials for all materials. It is therefore important that the sustainability performance of all materials is assessed on an objective "level playing field," which also highlights "hot spots" for sustainable innovation from supply-chain management through manufacturing, substance selection by material compounders, maintenance inputs in product use, and beyond product end-of-life. Chemical regulation must evolve to include and embed wider sustainability principles into operational practice and become applicable and enforced across increasingly global value chains. Integr Environ Assess Manag 2023;19:1131-1146. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Asunto(s)
Ecotoxicología , Desarrollo Sostenible , Humanos , Medición de Riesgo/métodos
7.
Breathe (Sheff) ; 18(1): 210148, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35284017

RESUMEN

While advocating for addressing "treatable traits" is admirable in that it reminds clinicians to consider the patient and not the disease, the use of this idea to promote dangerous changes in practice should be challenged. https://bit.ly/30VkP8Q.

8.
J Paediatr Child Health ; 58(6): 1066-1068, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35174574

RESUMEN

AIM: With progressive impairment of lung function, deposition of inhaled drug in the lungs becomes progressively more central, limiting its effectiveness. This pilot study explored the possibility that long slow inhalations might improve delivery of aerosol to the lung periphery in cystic fibrosis patients with moderate lung disease. METHODS: Five subjects aged 12-18 years (mean FEV1 72%; range 63-80%) inhaled a radiolabelled aerosol from a jet nebuliser on two occasions. Two inhalation techniques were compared: breathing tidally from a standard continuous output nebuliser and using long slow inhalations from the AKITA® JET system. RESULTS: Long slow breaths resulted in much lower oropharyngeal deposition with higher lung doses. Importantly, the peripheral lung increased proportionately. The increased lung dose is attributable to more of the larger inhaled droplets passing into the lower airways. This would be expected to increase the central deposition unless significantly more of the smaller droplets were able to penetrate deeper into the lungs. The data support improved delivery of drug to the distal lung when compared with tidal breathing. CONCLUSION: These pilot data suggest that this approach may prove to be clinically relevant in improving the efficacy of inhaled medication in those with moderate-severe lung disease.


Asunto(s)
Fibrosis Quística , Administración por Inhalación , Aerosoles/uso terapéutico , Fibrosis Quística/complicaciones , Fibrosis Quística/tratamiento farmacológico , Humanos , Pulmón , Nebulizadores y Vaporizadores , Proyectos Piloto
9.
Sci Total Environ ; 823: 153637, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35131238

RESUMEN

Ecosystem services provided by lowland British floodplains respectively under semi-natural conditions and converted for intensive maize production were assessed. Floodplains across lowland Britain have been extensively disconnected from river channels, depleting habitat for wildlife and other beneficial ecosystem services. Conservation measures are often regarded as costly constraints on economic and development freedoms whilst, conversely, conversion for intensive agricultural production is rewarded by markets despite many often-overlooked externalities. Maize growing has increased in Britain since the 1970s, initially for feedlot production of livestock and now increasingly for grant-aided biofuel production for anaerobic digestion. Comparative literature-based ecosystem service assessments using the RAWES (Rapid Assessment of Wetland Ecosystem Services) approach reveal that lowland British floodplains in semi-natural condition provide a wider range of provisioning services than those converted for monocultural intensive production of maize, in addition to a diversity of regulating, cultural and supporting service benefits that are lost or transformed into disservices when floodplains are converted for intensive maize growth. Benefits and disbenefits of floodplains managed under the two scenarios (semi-natural versus monocultural maize) are presented graphically as an intuitive means to support decision-makers. Monetisation of benefits would be risky, not merely due to uncertainties but as this may skew conclusions and subsequent decision-making towards maximisation of marketed or near-market services, consequently misrepresenting the diversity of values of whole socioecological floodplain systems. Management solutions protective of the societal values provided by floodplain ecosystem may include buffer zoning as a mitigation measure, but a more strategic solution may be zonation of land use based on suitability not only for crop production but recognising the full spectrum of societally beneficial ecosystem services demonstrated by RAWES assessment. A variety of drivers for a changing approach to floodplain farming - statutory, fiscal and self-beneficial - are highlighted, and are generically applicable beyond Britain with context-specific modification.


Asunto(s)
Ecosistema , Humedales , Agricultura , Animales , Conservación de los Recursos Naturales , Ganado , Ríos
10.
J Pers Med ; 12(1)2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35055397

RESUMEN

Many thousands of articles relating to asthma appear in medical and scientific journals each year, yet there is still no consensus as to how the condition should be defined. Some argue that the condition does not exist as an entity and that the term should be discarded. The key feature that distinguishes it from other respiratory diseases is that airway smooth muscles, which normally vary little in length, have lost their stable configuration and shorten excessively in response to a wide range of stimuli. The lungs' and airways' limited repertoire of responses results in patients with very different pathologies experiencing very similar symptoms and signs. In the absence of objective verification of airway smooth muscle (ASM) lability, over and underdiagnosis are all too common. Allergic inflammation can exacerbate symptoms but given that worldwide most asthmatics are not atopic, these are two discrete conditions. Comorbidities are common and are often responsible for symptoms attributed to asthma. Common amongst these are a chronic bacterial dysbiosis and dysfunctional breathing. For progress to be made in areas of therapy, diagnosis, monitoring and prevention, it is essential that a diagnosis of asthma is confirmed by objective tests and that all co-morbidities are accurately detailed.

11.
Front Microbiol ; 12: 711134, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35002989

RESUMEN

Introduction: The airway microbiota has been linked to specific paediatric respiratory diseases, but studies are often small. It remains unclear whether particular bacteria are associated with a given disease, or if a more general, non-specific microbiota association with disease exists, as suggested for the gut. We investigated overarching patterns of bacterial association with acute and chronic paediatric respiratory disease in an individual participant data (IPD) meta-analysis of 16S rRNA gene sequences from published respiratory microbiota studies. Methods: We obtained raw microbiota data from public repositories or via communication with corresponding authors. Cross-sectional analyses of the paediatric (<18 years) microbiota in acute and chronic respiratory conditions, with >10 case subjects were included. Sequence data were processed using a uniform bioinformatics pipeline, removing a potentially substantial source of variation. Microbiota differences across diagnoses were assessed using alpha- and beta-diversity approaches, machine learning, and biomarker analyses. Results: We ultimately included 20 studies containing individual data from 2624 children. Disease was associated with lower bacterial diversity in nasal and lower airway samples and higher relative abundances of specific nasal taxa including Streptococcus and Haemophilus. Machine learning success in assigning samples to diagnostic groupings varied with anatomical site, with positive predictive value and sensitivity ranging from 43 to 100 and 8 to 99%, respectively. Conclusion: IPD meta-analysis of the respiratory microbiota across multiple diseases allowed identification of a non-specific disease association which cannot be recognised by studying a single disease. Whilst imperfect, machine learning offers promise as a potential additional tool to aid clinical diagnosis.

12.
Pediatr Pulmonol ; 55(11): 3209-3214, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32915513

RESUMEN

Bronchoalveolar lavage (BAL) is widely regarded as providing "gold standard" samples for infective lower respiratory tract disease. Current approaches have been adopted empirically without robust assessment and hence carry many assumptions that have not been tested. Many of these uncertainties were highlighted in the ATS pediatric bronchoscopy guidelines. This study was designed to explore some of these issues. BAL was undertaken via an endotracheal tube in 13 subjects aged less than 6 years with persistent bacterial bronchitis and five healthy controls. Aliquots of the same pooled BAL sample were sent to two accredited laboratories. one producing semiquantitative results and the other quantitative results. For five patients potentially pathogenic bacteria were grown by one laboratory but not the other, while in three more there were discrepancies in the organisms reported. Despite being symptomatic and off antibiotics, only 3 of 13 patients were reported to have a pathogen at a density of more than 1 × 104 colony forming unit. There was at best a poor correlation between semiquantitative and quantitative data. Potential pathogens were cultured in two of five control samples. The results suggest that the results from conventional microbiological assessment of BAL samples can be highly variable and that the proposal that a discrete cut-off is of value in patients with chronic endobronchial infection is probably invalid.


Asunto(s)
Infecciones Bacterianas/microbiología , Bronquitis/microbiología , Líquido del Lavado Bronquioalveolar/microbiología , Lavado Broncoalveolar , Preescolar , Femenino , Humanos , Lactante , Intubación Intratraqueal , Masculino
13.
Environ Sci Policy ; 111: 7-17, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32501392

RESUMEN

There is rising international concern about the zoonotic origins of many global pandemics. Increasing human-animal interactions are perceived as driving factors in pathogen transfer, emphasising the close relationships between human, animal and environmental health. Contemporary livelihood and market patterns tend to degrade ecosystems and their services, driving a cycle of degradation in increasingly tightly linked socio-ecological systems. This contributes to reductions in the natural regulating capacities of ecosystem services to limit disease transfer from animals to humans. It also undermines natural resource availability, compromising measures such as washing and sanitation that may be key to managing subsequent human-to-human disease transmission. Human activities driving this degrading cycle tend to convert beneficial ecosystem services into disservices, exacerbating risks related to zoonotic diseases. Conversely, measures to protect or restore ecosystems constitute investment in foundational capital, enhancing their capacities to provide for greater human security and opportunity. We use the DPSIR (Drivers-Pressures-State change-Impact-Response) framework to explore three aspects of zoonotic diseases: (1) the significance of disease regulation ecosystem services and their degradation in the emergence of Covid-19 and other zoonotic diseases; and of the protection of natural resources as mitigating contributions to both (2) regulating human-to-human disease transfer; and (3) treatment of disease outbreaks. From this analysis, we identify a set of appropriate response options, recognising the foundational roles of ecosystems and the services they provide in risk management. Zoonotic disease risks are ultimately interlinked with biodiversity crises and water insecurity. The need to respond to the Covid-19 pandemic ongoing at the time of writing creates an opportunity for systemic policy change, placing scientific knowledge of the value and services of ecosystems at the heart of societal concerns as a key foundation for a more secure future. Rapid political responses and unprecedented economic stimuli reacting to the pandemic demonstrate that systemic change is achievable at scale and pace, and is also therefore transferrable to other existential, global-scale threats including climate change and the 'biodiversity crisis'. This also highlights the need for concerted global action, and is also consistent with the duties, and ultimately the self-interests, of developed, donor nations.

14.
Front Pediatr ; 8: 95, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32373557

RESUMEN

The defining feature of asthma is loss of normal post-natal homeostatic control of airways smooth muscle (ASM). This is the key feature that distinguishes asthma from all other forms of respiratory disease. Failure to focus on impaired ASM homeostasis largely explains our failure to find a cure and contributes to the widespread excessive morbidity associated with the condition despite the presence of effective therapies. The mechanisms responsible for destabilizing the normal tight control of ASM and hence airways caliber in post-natal life are unknown but it is clear that atopic inflammation is neither necessary nor sufficient. Loss of homeostasis results in excessive ASM contraction which, in those with poor control, is manifest by variations in airflow resistance over short periods of time. During viral exacerbations, the ability to respond to bronchodilators is partially or almost completely lost, resulting in ASM being "locked down" in a contracted state. Corticosteroids appear to restore normal or near normal homeostasis in those with poor control and restore bronchodilator responsiveness during exacerbations. The mechanism of action of corticosteroids is unknown and the assumption that their action is solely due to "anti-inflammatory" effects needs to be challenged. ASM, in evolutionary terms, dates to the earliest land dwelling creatures that required muscle to empty primitive lungs. ASM appears very early in embryonic development and active peristalsis is essential for the formation of the lungs. However, in post-natal life its only role appears to be to maintain airways in a configuration that minimizes resistance to airflow and dead space. In health, significant constriction is actively prevented, presumably through classic negative feedback loops. Disruption of this robust homeostatic control can develop at any age and results in asthma. In order to develop a cure, we need to move from our current focus on immunology and inflammatory pathways to work that will lead to an understanding of the mechanisms that contribute to ASM stability in health and how this is disrupted to cause asthma. This requires a radical change in the focus of most of "asthma research."

15.
Front Pediatr ; 8: 218, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32432064

RESUMEN

The diagnosis and management of infants and children with a significant viral lower respiratory tract illness remains the subject of much debate and little progress. Over the decades various terms for such illnesses have been in and fallen out of fashion or have evolved to mean different things to different clinicians. Terms such as "bronchiolitis," "reactive airways disease," "viral wheeze," and many more are used to describe the same condition and the same term is frequently used to describe illnesses caused by completely different dominant pathologies. This lack of clarity is due, in large part, to a failure to understand the basic underlying inflammatory and associated processes and, in part, due to the lack of a simple test to identify a condition such as asthma. Moreover, there is a lack of insight into the fact that the same pathology can produce different clinical signs at different ages. The consequence is that terminology and fashions in treatment have tended to go around in circles. As was noted almost 60 years ago, amongst pre-school children with a viral LRTI and airways obstruction there are those with a "viral bronchitis" and those with asthma. In the former group, a neutrophil dominated inflammation response is responsible for the airways' obstruction whilst amongst asthmatics much of the obstruction is attributable to bronchoconstriction. The airways obstruction in the former group is predominantly caused by airways secretions and to some extent mucosal oedema (a "snotty lung"). These patients benefit from good supportive care including supplemental oxygen if required (though those with a pre-existing bacterial bronchitis will also benefit from antibiotics). For those with a viral exacerbation of asthma, characterized by bronchoconstriction combined with impaired b-agonist responsiveness, standard management of an exacerbation of asthma (including the use of steroids to re-establish bronchodilator responsiveness) represents optimal treatment. The difficulty is identifying which group a particular patient falls into. A proposed simplified approach to the nomenclature used to categorize virus associated LRTIs is presented based on an understanding of the underlying pathological processes and how these contribute to the physical signs.

16.
Sci Total Environ ; 723: 138061, 2020 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-32220737

RESUMEN

Bhojtal, a large man-made lake bordering the city of Bhopal (Madhya Pradesh state, central India), is important for the city's water supply, connoted the lifeline of the city. Despite the dry though not arid and markedly seasonal climate, soil impermeability hampers infiltration into the complex geology underlying the Bhojtal catchment. Rural communities in the catchment are nonetheless high dependent on underlying aquifers. This paper develops baseline understanding of trends in the ecology, water quality and uses of Bhojtal, discussing their implications for the long-term wellbeing of the Bhopal city region. It highlights increasing dependency on water diverted from out-of-catchment sources, and also abstraction across the Bhojtal catchment in excess of replenishment that is depressing groundwater and contributing to reported declining lake level and water quality. Despite some nature-based management initiatives, evidence suggests little progress in haltering on-going groundwater depression and declines in lake water level and quality. Significant declines in ecosystem services produced by Bhojtal are likely without intervention, a major concern given the high dependency of people in the Bhopal region on Bhojtal for their water supply and socio-economic and cultural wellbeing. Over-reliance on appropriation of water from increasingly remote sources is currently compensating for lack of attention to measures protecting or regenerating local resources that may provide greater resilience and regional self-sufficiency. Improved knowledge of catchment hydrogeology on a highly localised scale could improve the targeting and efficiency of water harvesting and other management interventions in the Bhojtal catchment, and their appropriate hybridisation with engineered solutions, protecting the catchment from unintended impacts of water extraction or increasing its carrying capacity, and also providing resilience to rising population and climate change. Ecosystem service assessment provides useful insights into the breadth of benefits of improved management of Bhojtal and its catchment.

17.
Am J Respir Crit Care Med ; 201(11): 1358-1371, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32105156

RESUMEN

Rationale: Respiratory syncytial virus (RSV) bronchiolitis causes significant infant mortality. Bronchiolitis is characterized by airway epithelial cell (AEC) death; however, the mode of death remains unknown.Objectives: To determine whether necroptosis contributes to RSV bronchiolitis pathogenesis via HMGB1 (high mobility group box 1) release.Methods: Nasopharyngeal samples were collected from children presenting to the hospital with acute respiratory infection. Primary human AECs and neonatal mice were inoculated with RSV and murine Pneumovirus, respectively. Necroptosis was determined via viability assays and immunohistochemistry for RIPK1 (receptor-interacting protein kinase-1), MLKL (mixed lineage kinase domain-like pseudokinase) protein, and caspase-3. Necroptosis was blocked using pharmacological inhibitors and RIPK1 kinase-dead knockin mice.Measurements and Main Results: HMGB1 levels were elevated in nasopharyngeal samples of children with acute RSV infection. RSV-induced epithelial cell death was associated with increased phosphorylated RIPK1 and phosphorylated MLKL but not active caspase-3 expression. Inhibition of RIPK1 or MLKL attenuated RSV-induced HMGB1 translocation and release, and lowered viral load. MLKL inhibition increased active caspase-3 expression in a caspase-8/9-dependent manner. In susceptible mice, Pneumovirus infection upregulated RIPK1 and MLKL expression in the airway epithelium at 8 to 10 days after infection, coinciding with AEC sloughing, HMGB1 release, and neutrophilic inflammation. Genetic or pharmacological inhibition of RIPK1 or MLKL attenuated these pathologies, lowered viral load, and prevented type 2 inflammation and airway remodeling. Necroptosis inhibition in early life ameliorated asthma progression induced by viral or allergen challenge in later life.Conclusions: Pneumovirus infection induces AEC necroptosis. Inhibition of necroptosis may be a viable strategy to limit the severity of viral bronchiolitis and break its nexus with asthma.


Asunto(s)
Bronquiolitis/virología , Células Epiteliales/metabolismo , Células Epiteliales/patología , Proteína HMGB1/metabolismo , Necroptosis , Mucosa Respiratoria/citología , Infecciones por Virus Sincitial Respiratorio/metabolismo , Animales , Preescolar , Humanos , Lactante , Ratones , Estudios Prospectivos
18.
Sci Total Environ ; 704: 135451, 2020 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-31791782

RESUMEN

Arid and semi-arid regions of central India receive scarce and episodic precipitation during the short monsoon season, and also experience substantial evaporation. Traditional and innovative water harvesting and governance practices improve water stewardship, or abate some impacts of intensive mechanised water extraction. However, significant numbers of alien trees, in particular Eucalyptus species with high water demands, populate some regions practicing progressive water stewardship. The water demands of these trees can potentially undermine efforts to achieve water security. Through interviews with community leaders in Indian villages with differing eucalyptus tree densities, water loss through evapotranspiration compared with livelihood demands was approximated. Literature review of the water demands and ecosystem services provided respectively by alien eucalypts and native, culturally valued neem trees supports assessment of the likely benefits and acceptability of a replacement programme favouring native trees. Although data limitations mean that the findings of this study are necessarily uncertain, they nonetheless illustrate the likely scale of impact, substantiating the case for alien tree management as an important contribution to water security. Alien vegetation management practices as a contribution to water security are already firmly established in South Africa, and are likely to yield equivalent benefits if translated to dryland India.


Asunto(s)
Agricultura Forestal/métodos , Especies Introducidas , Árboles , Abastecimiento de Agua , Clima , Ecosistema , Eucalyptus , India , Estaciones del Año
19.
Eur Respir J ; 54(3)2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31320455

RESUMEN

Tracheomalacia and tracheobronchomalacia may be primary abnormalities of the large airways or associated with a wide variety of congenital and acquired conditions. The evidence on diagnosis, classification and management is scant. There is no universally accepted classification of severity. Clinical presentation includes early-onset stridor or fixed wheeze, recurrent infections, brassy cough and even near-death attacks, depending on the site and severity of the lesion. Diagnosis is usually made by flexible bronchoscopy in a free-breathing child but may also be shown by other dynamic imaging techniques such as low-contrast volume bronchography, computed tomography or magnetic resonance imaging. Lung function testing can provide supportive evidence but is not diagnostic. Management may be medical or surgical, depending on the nature and severity of the lesions, but the evidence base for any therapy is limited. While medical options that include bronchodilators, anti-muscarinic agents, mucolytics and antibiotics (as well as treatment of comorbidities and associated conditions) are used, there is currently little evidence for benefit. Chest physiotherapy is commonly prescribed, but the evidence base is poor. When symptoms are severe, surgical options include aortopexy or posterior tracheopexy, tracheal resection of short affected segments, internal stents and external airway splinting. If respiratory support is needed, continuous positive airway pressure is the most commonly used modality either via a face mask or tracheostomy. Parents of children with tracheobronchomalacia report diagnostic delays and anxieties about how to manage their child's condition, and want more information. There is a need for more research to establish an evidence base for malacia. This European Respiratory Society statement provides a review of the current literature to inform future study.


Asunto(s)
Broncomalacia/diagnóstico por imagen , Broncomalacia/terapia , Neumología/normas , Traqueomalacia/diagnóstico por imagen , Traqueomalacia/terapia , Broncoscopía , Niño , Europa (Continente) , Humanos , Imagen por Resonancia Magnética , Tomografía Computarizada Multidetector , Modalidades de Fisioterapia , Neumología/organización & administración , Pruebas de Función Respiratoria , Ruidos Respiratorios , Sociedades Médicas
20.
BMJ Open Respir Res ; 6(1): e000375, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31178996

RESUMEN

Introduction: Chronic cough in childhood is common and causes much parental anxiety. Eliciting a diagnosis can be difficult as it is a non-specific symptom indicating airways inflammation and this may be due to a variety of aetiologies. A key part of assessment is obtaining an accurate cough history. It has previously been shown that parental reporting of 'wheeze' is frequently inaccurate. This study aimed to determine whether parental reporting of the quality of a child's cough is likely to be accurate. Methods: Parents of 48 'new' patients presenting to a respiratory clinic with chronic cough were asked to describe the nature of their child's cough. They were then shown video clips of different types of cough using age-appropriate examples, and their initial report was compared with the types of cough chosen from the video. Results: In a quarter of cases, the parents chose a video clip of a 'dry' or 'wet' cough having given the opposite description. In a further 20% parents chose examples of both 'dry' and 'wet' coughs despite having used only one descriptor. Discussion: While the characteristics of a child's cough carry important information that may be helpful in reaching a diagnosis, clinicians should interpret parental reporting of the nature of a child's cough with some caution in that one person's 'dry' cough may very well be another person's 'wet' cough.


Asunto(s)
Tos/diagnóstico , Anamnesis/métodos , Padres , Autoinforme , Adolescente , Niño , Preescolar , Estudios de Factibilidad , Humanos , Reproducibilidad de los Resultados
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