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Biodiversity faces unprecedented threats from rapid global change1. Signals of biodiversity change come from time-series abundance datasets for thousands of species over large geographic and temporal scales. Analyses of these biodiversity datasets have pointed to varied trends in abundance, including increases and decreases. However, these analyses have not fully accounted for spatial, temporal and phylogenetic structures in the data. Here, using a new statistical framework, we show across ten high-profile biodiversity datasets2-11 that increases and decreases under existing approaches vanish once spatial, temporal and phylogenetic structures are accounted for. This is a consequence of existing approaches severely underestimating trend uncertainty and sometimes misestimating the trend direction. Under our revised average abundance trends that appropriately recognize uncertainty, we failed to observe a single increasing or decreasing trend at 95% credible intervals in our ten datasets. This emphasizes how little is known about biodiversity change across vast spatial and taxonomic scales. Despite this uncertainty at vast scales, we reveal improved local-scale prediction accuracy by accounting for spatial, temporal and phylogenetic structures. Improved prediction offers hope of estimating biodiversity change at policy-relevant scales, guiding adaptive conservation responses.
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Biodiversidade , Incerteza , Animais , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Conjuntos de Dados como Assunto , Filogenia , Análise Espaço-Temporal , Fatores de TempoRESUMO
The boundaries of the chart of nuclides contain exotic isotopes that possess extreme proton-to-neutron asymmetries. Here we report on strong evidence of ^{9}N, one of the most exotic proton-rich isotopes where more than one half of its constitute nucleons are unbound. With seven protons and two neutrons, this extremely proton-rich system would represent the first-known example of a ground-state five-proton emitter. The invariant-mass spectrum of its decay products can be fit with two peaks whose energies are consistent with the theoretical predictions of an open-quantum-system approach; however, we cannot rule out the possibility that only a single resonancelike peak is present in the spectrum.
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Accurate understanding of x-ray diagnostics is crucial for both interpreting high-energy-density experiments and testing simulations through quantitative comparisons. X-ray diagnostic models are complex. Past treatments of individual x-ray diagnostics on a case-by-case basis have hindered universal diagnostic understanding. Here, we derive a general formula for modeling the absolute response of non-focusing x-ray diagnostics, such as x-ray imagers, one-dimensional space-resolved spectrometers, and x-ray power diagnostics. The present model is useful for both data modeling and data processing. It naturally accounts for the x-ray crystal broadening. The new model verifies that standard approaches for a crystal response can be good approximations, but they can underestimate the total reflectivity and overestimate spectral resolving power by more than a factor of 2 in some cases near reflectivity edge features. We also find that a frequently used, simplified-crystal-response approximation for processing spectral data can introduce an absolute error of more than an order of magnitude and the relative spectral radiance error of a factor of 3. The present model is derived with straightforward geometric arguments. It is more general and is recommended for developing a unified picture and providing consistent treatment over multiple x-ray diagnostics. Such consistency is crucial for reliable multi-objective data analyses.
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The Z machine is a current driver producing up to 30 MA in 100 ns that utilizes a wide range of diagnostics to assess accelerator performance and target behavior conduct experiments that use the Z target as a source of radiation or high pressures. We review the existing suite of diagnostic systems, including their locations and primary configurations. The diagnostics are grouped in the following categories: pulsed power diagnostics, x-ray power and energy, x-ray spectroscopy, x-ray imaging (including backlighting, power flow, and velocimetry), and nuclear detectors (including neutron activation). We will also briefly summarize the primary imaging detectors we use at Z: image plates, x-ray and visible film, microchannel plates, and the ultrafast x-ray imager. The Z shot produces a harsh environment that interferes with diagnostic operation and data retrieval. We term these detrimental processes "threats" of which only partial quantifications and precise sources are known. We summarize the threats and describe techniques utilized in many of the systems to reduce noise and backgrounds.
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BACKGROUND: The large extracellular matrix protein SVEP1 mediates cell adhesion via integrin α9ß1. Recent studies have identified an association between a missense variant in SVEP1 and increased risk of coronary artery disease (CAD) in humans and in mice Svep1 deficiency alters the development of atherosclerotic plaques. However how SVEP1 functionally contributes to CAD pathogenesis is not fully understood. Monocyte recruitment and differentiation to macrophages is a key step in the development of atherosclerosis. Here, we investigated the requirement for SVEP1 in this process. METHODS: SVEP1 expression was measured during monocyte-macrophage differentiation in primary monocytes and THP-1 human monocytic cells. SVEP1 knockout THP-1 cell lines and the dual integrin α4ß1/α9ß1 inhibitor, BOP, were utilised to investigate the effect of these proteins in THP-1 cell adhesion, migration and cell spreading assays. Subsequent activation of downstream integrin signalling intermediaries was quantified by western blotting. RESULTS: SVEP1 gene expression increases in monocyte to macrophage differentiation in human primary monocytes and THP-1 cells. Using two SVEP1 knockout THP-1 cells we observed reduction in monocyte adhesion, migration, and cell spreading compared to control cells. Similar results were found with integrin α4ß1/α9ß1 inhibition. We demonstrate reduced activity of Rho and Rac1 in SVEP1 knockout THP-1 cells. CONCLUSIONS: SVEP1 regulates monocyte recruitment and differentiation phenotypes through an integrin α4ß1/α9ß1 dependent mechanism. GENERAL SIGNIFICANCE: These results describe a novel role for SVEP1 in monocyte behaviour relevant to CAD pathophysiology.
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Integrina alfa4beta1 , Monócitos , Humanos , Moléculas de Adesão Celular/metabolismo , Diferenciação Celular/genética , Integrina alfa4beta1/metabolismo , Macrófagos/metabolismoRESUMO
A ^{13}F resonance was observed following a charge-exchange reaction between a fast ^{13}O beam and a ^{9}Be target. The resonance was found in the invariant-mass distribution of 3p+^{10}C events and probably corresponds to a 5/2^{+} excited state. The ground state was also expected to be populated, but was not resolved from the background. The observed level decays via initial proton emissions to both the ground and first 2^{+} state of ^{12}O, which subsequently undergo 2p decay. In addition, there may also be a significant proton decay branch to the second 2^{+} level in ^{12}O. The wave function associated with the observed level may be collectivized due to coupling to the continuum as is it located just above the threshold for proton decay to the 2_{2}^{+} state of ^{12}O.
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Intense electron beams striking a high-atomic number target produce high-output pulsed photon fluxes for flash x-ray experiments. Without an external guide field, such beams are subject to the dynamics of high-current electron beam propagation, including changes to electron trajectories either from self-fields or from development of beam instabilities. The bremsstrahlung output (dose-rate) scales approximately as IVx, where I is the beam current, V the electron energy, and x is in the range 2.0-2.65 and depends upon the electron angle on the converter. Using experimental beam data (dose-rate, I and V), this equation can be solved for x, a process known as "inverting the radiographer's equation." Inversion methods that rely on thermoluminescent dosimeters, which are time-integrated, yield no information about evolution of the electron beam angle in time. We propose here an inversion method that uses several dose-rate monitors at different angles with respect to the beam axis. By measuring dose-rates at different angles, one can infer the time-dependent beam voltage and angle. This method compares well with estimates of corrected voltage and results in a self-consistent picture of beam dynamics. Techniques are demonstrated using data from self-magnetic pinch experiments at the RITS-6 facility at Sandia National Laboratories.
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The structure of the extremely proton-rich nucleus _{8}^{11}O_{3}, the mirror of the two-neutron halo nucleus _{3}^{11}Li_{8}, has been studied experimentally for the first time. Following two-neutron knockout reactions with a ^{13}O beam, the ^{11}O decay products were detected after two-proton emission and used to construct an invariant-mass spectrum. A broad peak of width â¼3.4 MeV was observed. Within the Gamow coupled-channel approach, it was concluded that this peak is a multiplet with contributions from the four lowest ^{11}O resonant states: J^{π}=3/2_{1}^{-}, 3/2_{2}^{-}, 5/2_{1}^{+}, and 5/2_{2}^{+}. The widths and configurations of these states show strong, nonmonotonic dependencies on the depth of the p-^{9}C potential. This unusual behavior is due to the presence of a broad threshold resonant state in ^{10}N, which is an analog of the virtual state in ^{10}Li in the presence of the Coulomb potential. After optimizing the model to the data, only a moderate isospin asymmetry between ground states of ^{11}O and ^{11}Li was found.
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In the self-magnetic-pinch diode, the electron beam, produced through explosive field emission, focuses on the anode surface due to its own magnetic field. This process results in dense plasma formation on the anode surface, consisting primarily of hydrocarbons. Direct measurements of the beam's current profile are necessary in order to understand the pinch dynamics and to determine x-ray source sizes, which should be minimized in radiographic applications. In this paper, the analysis of the C IV doublet (580.1 and 581.2 nm) line shapes will be discussed. The technique yields estimates of the electron density and electron temperature profiles, and the method can be highly beneficial in providing the current density distribution in such diodes.
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We study the sequential breakup of E/A=24.0 MeV ^{7}Li projectiles excited through inelastic interactions with C, Be, and Al target nuclei. For peripheral events that do not excite the target, we find very large spin alignment of the excited ^{7}Li projectiles longitudinal to the beam axis. This spin alignment is independent of the target used, and we propose a simple alignment mechanism that arises from an angular-momentum-excitation-energy mismatch. This mechanism is independent of the potential used for scattering and should be present in many scattering experiments.
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BACKGROUND: The present research aimed to investigate the efficacy of a multifaceted intervention that included motivational interviewing (MI) and psychoeducation in improving medication adherence (MA) among patients with bipolar disorder (BD). METHOD: A multicenter, cluster randomized, observer-blind, controlled, parallel-group trial was conducted in ten academic centers in Iran. Patients with BD were randomly assigned to the experimental group (EXP; n = 136) or the usual care group (UC; n = 134). The EXP group received five sessions of MI and psychoeducation together with their family members. The primary outcome measure was changes in scores on the Medication Adherence Rating Scale from baseline to 6 months post-intervention. Other outcome measures included serum levels of mood stabilizers, clinical symptoms, quality of life, as well as measures of intention, beliefs about medicine, perceived behavioral control, automaticity, action and coping planning, and adverse reactions. RESULTS: Medication adherence improved over time in both groups, but patients in the EXP group improved more (baseline score: 6.03; score at the sixth month: 9.55) than patients in the UC group (baseline score: 6.17; score at the sixth month: 6.67). In addition, patients in the EXP group showed greater improvement than patients in the UC group in almost all secondary outcomes 6 months following the intervention. CONCLUSIONS: Multifaceted interventions that include motivational-interviewing and psychoeducation can significantly improve MA and clinical and functional outcomes in patients with BD. TRIAL REGISTRATION NUMBER: The trial was registered with theClinicalTrials.gov database (NCT02241863) https://clinicaltrials.gov/ct2/show/NCT02241863.
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Transtorno Bipolar/tratamento farmacológico , Promoção da Saúde/métodos , Adesão à Medicação/psicologia , Entrevista Motivacional/métodos , Avaliação de Resultados em Cuidados de Saúde , Psicoterapia/métodos , Tranquilizantes , Adulto , Assistência ao Convalescente , Transtorno Bipolar/fisiopatologia , Feminino , Humanos , Masculino , Adesão à Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Método Simples-Cego , Tranquilizantes/sangueRESUMO
Diabetes disproportionately affects disadvantaged populations. Eighty percent of deaths directly caused by diabetes occurred in low- and middle-income countries. In high-income countries, there are marked disparities in diabetes control among racial/ethnic minorities and those with low socio-economic status. Innovative, effective and cost-effective strategies are needed to improve diabetes outcomes in these populations. Technological advances, peer educators and community health workers have expanded methodologies to reach, educate and monitor individuals with diabetes. In the present manuscript we review the outcomes of these strategies, and describe the barriers to and facilitators of these approaches for improving diabetes outcomes.
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Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/terapia , Terapias em Estudo/estatística & dados numéricos , Adulto , Criança , Serviços de Saúde Comunitária/economia , Serviços de Saúde Comunitária/estatística & dados numéricos , Agentes Comunitários de Saúde/economia , Agentes Comunitários de Saúde/estatística & dados numéricos , Custos e Análise de Custo , Diabetes Mellitus Tipo 1/economia , Diabetes Mellitus Tipo 2/economia , Saúde Global/economia , Saúde Global/estatística & dados numéricos , Disparidades em Assistência à Saúde/economia , Disparidades em Assistência à Saúde/estatística & dados numéricos , Humanos , Internet/economia , Internet/estatística & dados numéricos , Aplicativos Móveis/economia , Aplicativos Móveis/estatística & dados numéricos , Educação de Pacientes como Assunto/economia , Educação de Pacientes como Assunto/estatística & dados numéricos , Consulta Remota/economia , Consulta Remota/estatística & dados numéricos , Mídias Sociais/economia , Mídias Sociais/estatística & dados numéricos , Fatores Socioeconômicos , Telefone/economia , Telefone/estatística & dados numéricos , Terapias em Estudo/economia , Terapia Assistida por Computador/economia , Terapia Assistida por Computador/estatística & dados numéricos , Resultado do Tratamento , Populações VulneráveisRESUMO
For 24 h we measured continuously the variability of atmospheric refractivity over a volcano on the tropical island of Montserrat using a ground-based radar interferometer. We observed variations in phase that we interpret as due to changing water vapour on the propagation path between the radar and the volcano and we present them here in the context of the behaviour of the atmospheric boundary layer over the island. The water vapour behaviour was forced by diurnal processes, the passage of a synoptic-scale system and the presence of a plume of volcanic gas. The interferometer collected images of amplitude and phase every minute. From pairs of phase images, interferograms were calculated and analyzed every minute and averaged hourly, together with contemporaneous measurements of zenith delays estimated from a network of 14 GPS receivers. The standard deviation of phase at two sites on the volcano surface spanned a range of about 1-5 radians, the lowest values occurring at night on the lower slopes and the highest values during the day on the upper slopes. This was also reflected in spatial patterns of variability. Two-dimensional profiles of radar-measured delays were modelled using an atmosphere with water vapour content decreasing upwards and water vapour variability increasing upwards. Estimates of the effect of changing water vapour flux from the volcanic plume indicate that it should contribute only a few percent to this atmospheric variability. A diurnal cycle within the lower boundary layer producing a turbulence-dominated mixed layer during the day and stable layers at night is consistent with the observed refractivity.
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Acetaminofen/intoxicação , Overdose de Drogas/tratamento farmacológico , Enzimas Imobilizadas/química , Glucuronosiltransferase/química , Benzoquinonas/química , Enzimas Imobilizadas/uso terapêutico , Glucuronosiltransferase/uso terapêutico , Hepatócitos/efeitos dos fármacos , Humanos , Iminas/química , Fígado Artificial , UDP-Glucuronosiltransferase 1ARESUMO
The expression of epidermal growth factor receptor (EGFR/ERBB1/HER1) is implicated in the progress of numerous cancers, a feature that has been exploited in the development of EGFR antibodies and EGFR tyrosine kinase inhibitors as anti-cancer drugs. However, EGFR also has important normal cellular functions, leading to serious side effects when EGFR is inhibited. One damaging characteristic of many oncogenes is the ability to be expressed in the hypoxic conditions associated with the tumour interior. It has previously been demonstrated that expression of EGFR is maintained in hypoxic conditions via an unknown mechanism of translational control, despite global translation rates generally being attenuated under hypoxic conditions. In this report, we demonstrate that the human EGFR 5' untranslated region (UTR) sequence can initiate the expression of a downstream open reading frame via an internal ribosome entry site (IRES). We show that this effect is not due to either cryptic promoter activity or splicing events. We have investigated the requirement of the EGFR IRES for eukaryotic initiation factor 4A (eIF4A), which is an RNA helicase responsible for processing RNA secondary structure as part of translation initiation. Treatment with hippuristanol (a potent inhibitor of eIF4A) caused a decrease in EGFR 5' UTR-driven reporter activity and also a reduction in EGFR protein level. Importantly, we show that expression of a reporter gene under the control of the EGFR IRES is maintained under hypoxic conditions despite a fall in global translation rates.
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BACKGROUND AND PURPOSE: GoSlo-SR compounds are efficacious BK (KCa 1.1) channel openers, but little is known about their mechanism of action or effect on bladder contractility. We examined the effects of two closely related compounds on BK currents and bladder contractions. EXPERIMENTAL APPROACH: A combination of electrophysiology, molecular biology and synthetic chemistry was used to examine the effects of two novel channel agonists on BK channels from bladder smooth muscle cells and in HEK cells expressing BKα alone or in combination with either ß1 or ß4 subunits. KEY RESULTS: GoSlo-SR-5-6 shifted the voltage required for half maximal activation (V1/2 ) of BK channels approximately -100 mV, irrespective of the presence of regulatory ß subunits. The deaminated derivative, GoSlo-SR-5-130, also shifted the activation V1/2 in smooth muscle cells by approximately -100 mV; however, this was reduced by â¼80% in HEK cells expressing only BKα subunits. When ß1 or ß4 subunits were co-expressed with BKα, efficacy was restored. GoSlo-SR-5-130 caused a concentration-dependent reduction in spontaneous bladder contraction amplitude and this was abolished by iberiotoxin, consistent with an effect on BK channels. CONCLUSIONS AND IMPLICATIONS: GoSlo-SR-5-130 required ß1 or ß4 subunits to mediate its full effects, whereas GoSlo-SR-5-6 worked equally well in the absence or presence of ß subunits. GoSlo-SR-5-130 inhibited spontaneous bladder contractions by activating BK channels. The novel BK channel opener, GoSlo-SR-5-130, is approximately fivefold more efficacious on BK channels with regulatory ß subunits and may be a useful scaffold in the development of drugs to treat diseases such as overactive bladder.
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Antraquinonas/farmacologia , Subunidades beta do Canal de Potássio Ativado por Cálcio de Condutância Alta/fisiologia , Subunidades Proteicas/fisiologia , Ácidos Sulfônicos/farmacologia , Animais , Células Cultivadas , Células HEK293 , Humanos , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/agonistas , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/fisiologia , Subunidades beta do Canal de Potássio Ativado por Cálcio de Condutância Alta/agonistas , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Subunidades Proteicas/agonistas , Subunidades Proteicas/genética , Coelhos , Transfecção , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiologiaRESUMO
REASONS FOR PERFORMING STUDY: Evaluation of erythrocyte regeneration in horses is challenging, as they do not release reticulocytes into the peripheral blood. This study investigated transferrin receptor 1 (TfR1) expression in exosomes as a noninvasive method of characterising the regenerative response in anaemic horses. OBJECTIVES: To quantify TfR1 in ultraprecipitate of serum in horses before and after phlebotomy-induced anaemia, and to identify exosomes as the source of TfR1. The hypothesis was that serum exosomal TfR1 expression would increase during a regenerative response. STUDY DESIGN: Experimental model of anaemia. METHODS: Six horses were phlebotomised to achieve a 25% decrease in packed cell volume. Transferrin receptor 1 quantity in exosomes was determined by western blot and relative densitometry before and after phlebotomy. The size and density of the TfR1-associated particles were confirmed by transmission electron microscopy and density gradient centrifugation, respectively. RESULTS: Regenerative anaemia was confirmed by decreased packed cell volumes and decreased myeloid:erythroid ratios in the bone marrow. In all 6 horses, TfR1 expression increased between Days 7 and 10. Mean TfR1 levels peaked on Day 10 and at 3-fold higher than levels on Day 0. Appropriately sized particles were evident on transmission electron microscopy and sucrose density gradient fractions expected to contain exosomes also contained TfR1. CONCLUSIONS: These data indicate that TfR1 expression in serum exosomes may provide a marker for regeneration in anaemic horses.
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Anemia/veterinária , Exossomos/metabolismo , Regulação da Expressão Gênica/fisiologia , Doenças dos Cavalos/metabolismo , Receptores da Transferrina/metabolismo , Anemia/sangue , Anemia/metabolismo , Animais , Biomarcadores , Feminino , Doenças dos Cavalos/sangue , Cavalos , Masculino , Receptores da Transferrina/sangue , Receptores da Transferrina/genéticaRESUMO
BACKGROUND: The past two decades have seen a great improvement in the care of people with Prader-Willi syndrome (PWS), particularly with regard to control of diet and behaviour management. Has this affected mortality rates or thrown up new issues regarding premature ageing or dementia? We investigated two aspects of ageing in people with PWS: (1) an estimate of mortality over 9 years in a cohort of people with PWS, originally recruited in 1998-2000; and (2) premature ageing or dementia in people aged ⩾40 years. METHOD: (1) A follow-up of the population-based 1998-2000 cohort to investigate the subsequent mortality rate; and (2) the recruitment and structured assessment of all members of the Prader-Willi Syndrome Association UK (PWSA-UK) aged ⩾40 years who agreed to participate. RESULTS: Follow-up of the population-based 1998-2000 cohort gave a mortality rate of at least 7/62 over 9 years (1.25% per annum; 20 untraced), age at death was between 13 and 59 years. Twenty-six members of the PWSA-UK aged ⩾40 years were recruited, 18 of whom had a genetic diagnosis (gd) of PWS. Twenty-two (14 gd) showed no evidence of dementia. Four, with possible symptoms, are described in more detail; all are female, of maternal uniparental disomy (mUPD) genetic subtype, or have a disomic region, and all have a long history of psychotic illness. CONCLUSIONS: The mortality rate in people with PWS seems to be declining. The subgroup of people with PWS due to UPD or disomic region with female gender and a history of psychosis may be at risk of early onset dementia.
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Envelhecimento , Doença de Alzheimer/epidemiologia , Síndrome de Prader-Willi/complicações , Síndrome de Prader-Willi/genética , Síndrome de Prader-Willi/mortalidade , Adolescente , Adulto , Senilidade Prematura , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Dissomia Uniparental , Reino Unido/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Infancy is a developmental stage with heightened susceptibility to environmental influences on the risk of chronic childhood disease. Few birth cohort studies have detailed measures of fungal diversity data in infants' bedrooms, limiting the potential to measure long-term associations of these complex exposures with development of asthma or allergy. OBJECTIVE: We evaluated the relation of home fungal levels in infancy to repeated measures of wheeze and development of asthma and rhinitis by age 13, and sensitization by age 12 years. METHODS: In the Epidemiology of Home Allergens and Asthma prospective birth cohort study, we recruited 408 children with family history of allergic disease or asthma. When children were aged 2-3 months, we measured culturable fungi in bedroom air and dust, and in outdoor air. Main outcomes included ascertainment of symptoms/disease onset by questionnaire from birth through age 13. We estimated hazard ratios and, for wheeze and sensitization, odds ratios for an interquartile increase in log-transformed fungal concentrations, adjusting for other outcome predictors and potential confounders. RESULTS: Elevated levels of yeasts in bedroom floor dust were associated with reduced: i) wheeze at any age; ii) fungal sensitization; and iii) asthma development by age 13 (hazard ratio (HR) = 0.86; 95% confidence interval (CI), [0.75 to 0.98]). Outdoor airborne Cladosporium and dustborne Aspergillus predicted increased rhinitis. Risk of fungal sensitization by age 12, in response to environmental Alternaria and Aspergillus, was elevated in children with a maternal history of fungal sensitization. CONCLUSIONS AND CLINICAL RELEVANCE: Despite the irritant and allergenic properties of fungi, early-life elevated dust yeast exposures or their components may be protective against allergy and asthma in children at risk for these outcomes. Ascertainment of fungal components associated with immunoprotective effects may have therapeutic relevance for asthma.
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Poluição do Ar em Ambientes Fechados , Asma , Fungos , Asma/epidemiologia , Asma/etiologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Estudos RetrospectivosRESUMO
BACKGROUND: Mesenchymal stem cells (MSCs) decrease airway eosinophilia, airway hyperresponsiveness (AHR), and remodelling in murine models of acutely induced asthma. We hypothesized that MSCs would diminish these hallmark features in a chronic feline asthma model. OBJECTIVE: To document effects of allogeneic, adipose-derived MSCs on airway inflammation, AHR, and remodelling over time and investigate mechanisms by which MSCs alter local and systemic immunologic responses in chronic experimental feline allergic asthma. METHODS: Cats with chronic, experimentally induced asthma received six intravenous infusions of MSCs (0.36-2.5 × 10E7 MSCs/infusion) or placebo bimonthly at the time of study enrollment. Cats were evaluated at baseline and longitudinally for 1 year. Outcome measures included: bronchoalveolar lavage fluid cytology to assess airway eosinophilia, pulmonary mechanics and clinical scoring to assess AHR, and thoracic computed tomographic (CT) scans to assess structural changes (airway remodelling). CT scans were evaluated using a scoring system for lung attenuation (LA) and bronchial wall thickening (BWT). To assess mechanisms of MSC action, immunologic assays including allergen-specific IgE, cellular IL-10 production, and allergen-specific lymphocyte proliferation were performed. RESULTS: There were no differences between treatment groups or over time with respect to airway eosinophilia or AHR. However, significantly lower LA and BWT scores were noted in CT images of MSC-treated animals compared to placebo-treated cats at month 8 of the study (LA P = 0.0311; BWT P = 0.0489). No differences were noted between groups in the immunologic assays. CONCLUSIONS AND CLINICAL RELEVANCE: When administered after development of chronic allergic feline asthma, MSCs failed to reduce airway inflammation and AHR. However, repeated administration of MSCs at the start of study did reduce computed tomographic measures of airway remodelling by month 8, although the effect was not sustained at month 12. Further study of MSC therapy including repeated MSC administration is warranted to assess impact on remodelling in chronic asthma.