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BACKGROUND: The role of IL-13 on the airway epithelium in severe asthma leading to airway remodeling remains poorly understood. OBJECTIVE: To study IL-13 induced airway remodeling on goblet cells and cilia in the airway epithelium in severe asthma and the impact of an anti-IL4Rα antibody, dupilumab, in vitro. METHODS: Quantitative CT (qCT) lungs and endobronchial biopsies and brushings were obtained in 51 participants (22 severe, 11 non-severe asthma and 18 healthy participants) in the Severe Asthma Research Program (SARPIII) and measured for mucin and cilia related proteins. Epithelial cells were differentiated in air-liquid interphase (ALI) with IL-13 +/-dupilumab and assessed for mucin, cilia, cilia beat frequency (CBF) and epithelial integrity (transepithelial electrical resistance, TEER). RESULTS: Increased Muc5AC (Δ+263.2±92.7 lums/EpiArea) and decreased ciliated cells (Δ-0.07±0.03 Foxj1+cells/EpiArea) were observed in biopsies from severe asthma when compared to healthy (p<0.01 and p=0.047 respectively). RNAseq of epithelial cell brushes confirmed a Muc5AC increase with a decrease in a 5-gene cilia-related mean in severe asthma compared to healthy (all p<0.05). IL-13 (5 ng/mL) differentiated ALI cultures of healthy and asthmatic (severe and non-severe participants) increased Muc5AC, decreased cilia (α-acytl-tubulin) in healthy (Δ+6.5±1.5%, Δ-14.1±2.7%; all p<0.001 respectively) and asthma (Δ+4.4±2.5%, Δ-13.1±2.7%; p=0.084, p<0.001 respectively); decreased epithelial integrity (TEER) in healthy (-140.9±21.3 [ohms], p<0.001) while decreasing CBF in asthma (Δ-4.4±1.7 [Hz], p<0.01). When dupilumab was added to ALI with IL-13, there was no significant decrease in Mu5AC but there was restoration of cilia in healthy and asthma participants (absolute increase of 67.5% and 32.5% cilia, all p<0.05 respectively) while CBF increased (Δ+3.6±1.1 [Hz], p<0.001) and TEER decreased (only in asthma Δ-37.8±16.2 [ohms] p<0.05). CONCLUSIONS: IL-13 drives features of airway remodeling in severe asthma which are partially reversed by inhibiting IL-4Rα receptor in vitro.
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Rationale: Density thresholds in computed tomography (CT) lung scans quantify air trapping (AT) at the whole-lung level but are not informative for AT in specific bronchopulmonary segments. Objectives: To apply a segment-based measure of AT in asthma to investigate the clinical determinants of AT in asthma. Methods: In each of 19 bronchopulmonary segments in CT lung scans from 199 patients with asthma, AT was categorized as present if lung attenuation was less than -856 Hounsfield units at expiration in ⩾15% of the lung area. The resulting AT segment score (0-19) was related to patient outcomes. Measurements and Main Results: AT varied at the lung segment level and tended to persist at the patient and lung segment levels over 3 years. Patients with widespread AT (⩾10 segments) had more severe asthma (P < 0.05). The mean (±SD) AT segment score in patients with a body mass index ⩾30 kg/m2 was lower than in patients with a body mass index <30 kg/m2 (3.5 ± 4.6 vs. 5.5 ± 6.3; P = 0.008), and the frequency of AT in lower lobe segments in obese patients was less than in upper and middle lobe segments (35% vs. 46%; P = 0.001). The AT segment score in patients with sputum eosinophils ⩾2% was higher than in patients without sputum eosinophilia (7.0 ± 6.1 vs. 3.3 ± 4.9; P < 0.0001). Lung segments with AT more frequently had airway mucus plugging than lung segments without AT (48% vs. 18%; P ⩽ 0.0001). Conclusions: In patients with asthma, air trapping is more severe in those with airway eosinophilia and mucus plugging, whereas those who are obese have less severe trapping because their lower lobe segments are spared.
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Asma , Eosinofilia , Obesidade , Tomografia Computadorizada por Raios X , Humanos , Asma/diagnóstico por imagem , Asma/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/fisiopatologia , Adulto , Eosinofilia/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Idoso , Índice de Massa CorporalRESUMO
BACKGROUND: The relative utility of eosinophil peroxidase (EPX) and blood and sputum eosinophil counts as disease biomarkers in asthma is uncertain. OBJECTIVE: We sought to determine the utility of EPX as a biomarker of systemic and airway eosinophilic inflammation in asthma. METHODS: EPX protein was measured by immunoassay in serum and sputum in 110 healthy controls to establish a normal reference range and in repeated samples of serum and sputum collected during 3 years of observation in 480 participants in the Severe Asthma Research Program 3. RESULTS: Over 3 years, EPX levels in patients with asthma were higher than normal in 27% to 31% of serum samples and 36% to 53% of sputum samples. Eosinophils and EPX correlated better in blood than in sputum (rs values of 0.74 and 0.43, respectively), and high sputum EPX levels occurred in 27% of participants with blood eosinophil counts less than 150 cells/µL and 42% of participants with blood eosinophil counts between 150 and 299 cells/µL. Patients with persistently high sputum EPX values for 3 years were characterized by severe airflow obstruction, frequent exacerbations, and high mucus plug scores. In 59 patients with asthma who started mepolizumab during observation, serum EPX levels normalized in 96% but sputum EPX normalized in only 49%. Lung function remained abnormal even when sputum EPX normalized. CONCLUSIONS: Serum EPX is a valid protein biomarker of systemic eosinophilic inflammation in asthma, and sputum EPX levels are a more sensitive biomarker of airway eosinophilic inflammation than sputum eosinophil counts. Eosinophil measures in blood frequently miss airway eosinophilic inflammation, and mepolizumab frequently fails to normalize airway eosinophilic inflammation even though it invariably normalizes systemic eosinophilic inflammation.
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Manipulating spin transport enhances the functionality of electronic devices, allowing them to surpass physical constraints related to speed and power. For this reason, the use of van der Waals multiferroics at the interface of heterostructures offers promising prospects for developing high-performance devices, enabling the electrical control of spin information. Our work focuses primarily on a mechanism for multiferroicity in two-dimensional van der Waals materials that stems from an interplay between antiferromagnetism and the breaking of inversion symmetry in certain bilayers. We provide evidence for spin-electrical couplings that include manipulating van der Waals multiferroic edges via external voltages and the subsequent control of spin transport including for fully multiferroic spin field-effect transistors.
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Secreted deoxyribonucleases (DNases), such as DNase-I and DNase-IL3, degrade extracellular DNA, and endogenous DNases have roles in resolving airway inflammation and guarding against autoimmune responses to nucleotides. Subsets of patients with asthma have high airway DNA levels, but information about DNase activity in health and in asthma is lacking. To characterize DNase activity in health and in asthma, we developed a novel kinetic assay using a Taqman probe sequence that is quickly cleaved by DNase-I to produce a large product signal. We used this kinetic assay to measure DNase activity in sputum from participants in the Severe Asthma Research Program (SARP)-3 (n = 439) and from healthy controls (n = 89). We found that DNase activity was lower than normal in asthma [78.7 relative fluorescence units (RFU)/min vs. 120.4 RFU/min, P < 0.0001]. Compared to patients with asthma with sputum DNase activity in the upper tertile activity levels, those in the lower tertile of sputum DNase activity were characterized clinically by more severe disease and pathologically by airway eosinophilia and airway mucus plugging. Carbamylation of DNase-I, a post-translational modification that can be mediated by eosinophil peroxidase, inactivated DNase-I. In summary, a Taqman probe-based DNase activity assay uncovers low DNase activity in the asthma airway that is associated with more severe disease and airway mucus plugging and may be caused, at least in part, by eosinophil-mediated carbamylation.NEW & NOTEWORTHY We developed a new DNase assay and used it to show that DNase activity is impaired in asthma airways.
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Asma , Desoxirribonuclease I , Escarro , Humanos , Asma/metabolismo , Asma/enzimologia , Feminino , Masculino , Escarro/metabolismo , Escarro/enzimologia , Adulto , Pessoa de Meia-Idade , Desoxirribonuclease I/metabolismo , Desoxirribonucleases/metabolismoRESUMO
BACKGROUND: Long COVID impacts â¼10% of people diagnosed with COVID-19, yet the pathophysiology driving ongoing symptoms is poorly understood. We hypothesised that 129Xe magnetic resonance imaging (MRI) could identify unique pulmonary phenotypic subgroups of long COVID, therefore we evaluated ventilation and gas exchange measurements with cluster analysis to generate imaging-based phenotypes. METHODS: COVID-negative controls and participants who previously tested positive for COVID-19 underwent 129XeMRI â¼14-months post-acute infection across three centres. Long COVID was defined as persistent dyspnea, chest tightness, cough, fatigue, nausea and/or loss of taste/smell at MRI; participants reporting no symptoms were considered fully-recovered. 129XeMRI ventilation defect percent (VDP) and membrane (Mem)/Gas, red blood cell (RBC)/Mem and RBC/Gas ratios were used in k-means clustering for long COVID, and measurements were compared using ANOVA with post-hoc Bonferroni correction. RESULTS: We evaluated 135 participants across three centres: 28 COVID-negative (40±16yrs), 34 fully-recovered (42±14yrs) and 73 long COVID (49±13yrs). RBC/Mem (p=0.03) and FEV1 (p=0.04) were different between long- and COVID-negative; FEV1 and all other pulmonary function tests (PFTs) were within normal ranges. Four unique long COVID clusters were identified compared with recovered and COVID-negative. Cluster1 was the youngest with normal MRI and mild gas-trapping; Cluster2 was the oldest, characterised by reduced RBC/Mem but normal PFTs; Cluster3 had mildly increased Mem/Gas with normal PFTs; and Cluster4 had markedly increased Mem/Gas with concomitant reduction in RBC/Mem and restrictive PFT pattern. CONCLUSION: We identified four 129XeMRI long COVID phenotypes with distinct characteristics. 129XeMRI can dissect pathophysiologic heterogeneity of long COVID to enable personalised patient care.
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INTRODUCTION: Previous bronchoalveolar lavage fluid (BALF) proteomic analysis has evaluated limited numbers of subjects for only a few proteins of interest, which may differ between asthma and normal controls. Our objective was to examine a more comprehensive inflammatory biomarker panel in quantitative proteomic analysis for a large asthma cohort to identify molecular phenotypes distinguishing severe from nonsevere asthma. METHODS: Bronchoalveolar lavage fluid from 48 severe and 77 nonsevere adult asthma subjects were assessed for 75 inflammatory proteins, normalized to BALF total protein concentration. Validation of BALF differences was sought through equivalent protein analysis of autologous sputum. Subjects' data, stratified by asthma severity, were analysed by standard statistical tests, principal component analysis and 5 machine learning algorithms. RESULTS: The severe group had lower lung function and greater health care utilization. Significantly increased BALF proteins for severe asthma compared to nonsevere asthma were fibroblast growth factor 2 (FGF2), TGFα, IL1Ra, IL2, IL4, CCL8, CCL13 and CXCL7 and significantly decreased were platelet-derived growth factor a-a dimer (PDGFaa), vascular endothelial growth factor (VEGF), interleukin 5 (IL5), CCL17, CCL22, CXCL9 and CXCL10. Four protein differences were replicated in sputum. FGF2, PDGFaa and CXCL7 were independently identified by 5 machine learning algorithms as the most important variables for discriminating severe and nonsevere asthma. Increased and decreased proteins identified for the severe cluster showed significant protein-protein interactions for chemokine and cytokine signalling, growth factor activity, and eosinophil and neutrophil chemotaxis differing between subjects with severe and nonsevere asthma. CONCLUSION: These inflammatory protein results confirm altered airway remodelling and cytokine/chemokine activity recruiting leukocytes into the airways of severe compared to nonsevere asthma as important processes even in stable status.
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Asma , Fator A de Crescimento do Endotélio Vascular , Adulto , Humanos , Proteômica , Fator 2 de Crescimento de Fibroblastos , Citocinas/metabolismo , Lavagem Broncoalveolar , Quimiocinas , Líquido da Lavagem BroncoalveolarRESUMO
Computing the agreement between 2 continuous sequences is of great interest in statistics when comparing 2 instruments or one instrument with a gold standard. The probability of agreement quantifies the similarity between 2 variables of interest, and it is useful for determining what constitutes a practically important difference. In this article, we introduce a generalization of the PA for the treatment of spatial variables. Our proposal makes the PA dependent on the spatial lag. We establish the conditions for which the PA decays as a function of the distance lag for isotropic stationary and nonstationary spatial processes. Estimation is addressed through a first-order approximation that guarantees the asymptotic normality of the sample version of the PA. The sensitivity of the PA with respect to the covariance parameters is studied for finite sample size. The new method is described and illustrated with real data involving autumnal changes in the green chromatic coordinate (Gcc), an index of "greenness" that captures the phenological stage of tree leaves, is associated with carbon flux from ecosystems, and is estimated from repeated images of forest canopies.
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Ecossistema , Florestas , Probabilidade , Tamanho da AmostraRESUMO
BACKGROUND: Early life respiratory syncytial virus (RSV) bronchiolitis is a significant risk factor for childhood asthma. In vitro and in vivo studies suggested that decreasing levels of airway matrix metalloproteinase (MMP)-9 during RSV bronchiolitis may be associated with clinical benefits. OBJECTIVE: To investigate whether azithromycin therapy during severe RSV bronchiolitis reduces upper airway MMP-9 levels, whether upper airway MMP-9 levels correlate with upper airway interleukin IL-8 levels, and whether MMP-9 level reduction is associated with reduced post-RSV recurrent wheeze (RW). METHODS: A total of 200 otherwise healthy 1- to 18-month-old infants hospitalized with RSV bronchiolitis were randomized into a double-blind, placebo-controlled trial of oral azithromycin (10 mg/kg daily for 7 days followed by 5 mg/kg daily for 7 days) or placebo. Infants were followed for 2 to 4 years for the outcome of RW (3 or more wheezing episodes). Nasal lavage samples for MMP-9 levels were obtained at baseline, day 14 (end of the study treatment), and after 6 months. RESULTS: Upper airway MMP-9 levels were highly correlated with IL-8 levels at all 3 time points: randomization, day 14, and 6 months (r = 0.80; P < .0001 for all time points). MMP-9 levels were similar between treatment groups at randomization, were lower on day 14 among children treated with azithromycin (P = .0085), but no longer different after 6 months. MMP-9 levels at baseline and change from baseline to day 14 were not associated with the development of RW (P = .49, .39, respectively). CONCLUSION: Azithromycin therapy in children hospitalized with RSV bronchiolitis had a short-term anti-inflammatory effect in reducing upper airway MMP-9 levels. However, the reduction in MMP-9 levels did not relate to subsequent RW post-RSV. TRIAL REGISTRATION: This study is a secondary analysis of the Azithromycin to Prevent Wheezing following severe RSV bronchiolitis-II clinical trial registered at Clinicaltrials.gov (NCT02911935).
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Azitromicina , Metaloproteinase 9 da Matriz , Sons Respiratórios , Infecções por Vírus Respiratório Sincicial , Humanos , Azitromicina/uso terapêutico , Metaloproteinase 9 da Matriz/metabolismo , Lactente , Sons Respiratórios/efeitos dos fármacos , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Masculino , Feminino , Método Duplo-Cego , Bronquiolite Viral/tratamento farmacológico , Antibacterianos/uso terapêutico , Interleucina-8/metabolismo , Recidiva , HospitalizaçãoRESUMO
We provide a model capable of accounting for the multiferroicity in certain materials. The model's base is on free electrons and spin moments coupled within nonrelativistic quantum mechanics. The synergistic interplay between the magnetic and electric degrees of freedom that turns into the multiferroic phenomena occurs at a profound quantum mechanical level, conjured by Berry's phases and the quantum theory of polarization. Our results highlight the geometrical nature of the multiferroic order parameter that naturally leads to magnetoelectric domain walls, with promising technological potential.
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This paper introduces a new family of quantile regression models whose response variable follows a reparameterized Marshall-Olkin distribution indexed by quantile, scale, and asymmetry parameters. The family has arisen by applying the Marshall-Olkin approach to distributions belonging to the location-scale family. Models of higher flexibility and whose structure is similar to generalized linear models were generated by quantile reparameterization. The maximum likelihood (ML) method is presented for the estimation of the model parameters, and simulation studies evaluated the performance of the ML estimators. The advantages of the family are illustrated through an application to a set of nutritional data, whose results indicate it is a good alternative for modeling slightly asymmetric response variables with support on the real line.
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BACKGROUND: Body size and echolocation call frequencies are related in bats. However, it is unclear if this allometry applies to the entire clade. Differences have been suggested between nasal and oral emitting bats, as well as between some taxonomic families. Additionally, the scaling of other echolocation parameters, such as bandwidth and call duration, needs further testing. Moreover, it would be also interesting to test whether changes in body size have been coupled with changes in these echolocation parameters throughout bat evolution. Here, we test the scaling of peak frequency, bandwidth, and call duration with body mass using phylogenetically informed analyses for 314 bat species. We specifically tested whether all these scaling patterns differ between nasal and oral emitting bats. Then, we applied recently developed Bayesian statistical techniques based on large-scale simulations to test for the existence of correlated evolution between body mass and echolocation. RESULTS: Our results showed that echolocation peak frequencies, bandwidth, and duration follow significant allometric patterns in both nasal and oral emitting bats. Changes in these traits seem to have been coupled across the laryngeal echolocation bats diversification. Scaling and correlated evolution analyses revealed that body mass is more related to peak frequency and call duration than to bandwidth. We exposed two non-exclusive kinds of mechanisms to explain the link between size and each of the echolocation parameters. CONCLUSIONS: The incorporation of Bayesian statistics based on large-scale simulations could be helpful for answering macroevolutionary patterns related to the coevolution of traits in bats and other taxonomic groups.
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Quirópteros , Ecolocação , Humanos , Animais , Teorema de Bayes , Tamanho CorporalRESUMO
Purpose: The iPREDICT program aimed to develop an integrated digital health solution capable of continuous data streaming, predicting changes in asthma control, and enabling early intervention. Patients and Methods: As part of the iPREDICT program, asthma triggers were characterized by surveying 221 patients (aged ≥18 years) with self-reported asthma for a risk-benefit analysis of parameters predictive of changes in disease control. Seventeen healthy volunteers (age 25-65 years) tested 13 devices to measure these parameters and assessed their usability attributes. Results: Patients identified irritants such as chemicals, allergens, weather changes, and physical activity as triggers that were the most relevant to deteriorating asthma control. Device testing in healthy volunteers revealed variable data formats/units and quality issues, such as missing data and low signal-to-noise ratio. Based on user preference and data capture validity, a spirometer, vital sign monitor, and sleep monitor formed the iPREDICT integrated system for continuous data streaming to develop a personalized/predictive algorithm for asthma control. Conclusion: These findings emphasize the need to systematically compare devices based on several parameters, including usability and data quality, to develop integrated digital technology programs for asthma care.
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The extreme low humidity and temperatures in Antarctica make it one of the harsher areas for life on our planet. In a global change context, environmental barriers that prevented the arrival of alien species in Antarctica are weakening. Deception Island, one of the four active volcanoes of Antarctica, is especially vulnerable to the impacts of alien species. Geothermal areas (GA) in this Island offer unique microclimatic conditions that could differentially affect native and alien soil arthropods. Here we explore the desiccation tolerance of a native (Cryptopygus antarcticus) and an alien (Proisotoma minuta) springtail (Collembola) species to these extreme environmental conditions. GA and non-geothermal areas (NGA) were selected to evaluate intra- and interspecific variation in desiccation tolerance. Populations of P. minuta from GA had greater desiccation tolerance than populations from NGA. However, desiccation tolerance of C. antarcticus did not differ between GA and NGA. This native species had greater desiccation tolerance than the alien P. minuta, but also greater body size. Our findings show that the alien P. minuta responds differently to environmental conditions than the native C. antarcticus. Furthermore, body size may influence desiccation tolerance in these two springtail species.
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Artrópodes , Dessecação , Animais , Regiões Antárticas , Artrópodes/fisiologia , TemperaturaRESUMO
Background/Objectives: Positive margins are associated with locoregional recurrence in early laryngeal cancer. The aim of this study was to evaluate the impacts of specimen-driven (ex vivo) positive margins on patients with early-stage laryngeal cancer whose tumor bed (defect-driven) margins had been negative. Methods: A retrospective study was performed on 60 consecutive T1b/T2 glottic cancer patients who underwent open frontolateral laryngectomy. The intraoperative margins were obtained from the tumor bed. Their recurrence and disease-free survival were evaluated. In all cases, negative margins were obtained from the surgical bed. The impact of positive margins from the specimen was evaluated in a paraffin study. Results: Among 10 patients with positive margins in the specimen, six experienced local relapse, and among 50 patients with negative margins in the specimen, three developed recurrence. The 5-year disease-free survival rates were 37.5% and 93.9%, respectively (p < 0.001; log-rank). Even with negative margins in the surgical bed, patients with positive margins in the specimen at the final histopathological examination had a 3.5-fold higher chance of developing local recurrence than those with negative margins (HR = 13.993; 95% CI: 3.479-56.281; p < 0.001; univariate Cox regression). Conclusions: Specimen-driven positive margins represent a significant risk factor for local recurrence, even under negative margins at the tumor bed.
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BACKGROUND: The individualized PREdiction of DIsease Control using digital sensor Technology (iPREDICT) program was developed for asthma management using digital technology. Devices were integrated into daily lives of patients to establish a predictive model of asthma control by measuring changes from baseline health status with minimal device burden. OBJECTIVES: To establish baseline disease characteristics of the study participants, detect changes from baseline associated with asthma events, and evaluate algorithms capable of identifying triggers and predicting asthma control changes from baseline data. Patient experience and compliance with the devices were also explored. DESIGN: This was a multicenter, observational, 24-week, proof-of-concept study conducted in the United States. METHODS: Patients (⩾12 years) with severe, uncontrolled asthma engaged with a spirometer, vital sign monitor, sleep monitor, connected inhaler devices, and two mobile applications with embedded patient-reported outcome (PRO) questionnaires. Prospective data were linked to data from electronic health records and transmitted to a secure platform to develop predictive algorithms. The primary endpoint was an asthma event: symptom worsening logged by patients (PRO); peak expiratory flow (PEF) < 65% or forced expiratory volume in 1 s < 80%; increased short-acting ß2-agonist (SABA) use (>8 puffs/24 h or >4 puffs/day/48 h). For each endpoint, predictive models were constructed at population, subgroup, and individual levels. RESULTS: Overall, 108 patients were selected: 66 (61.1%) completed and 42 (38.9%) were excluded for failure to respond/missing data. Predictive accuracy depended on endpoint selection. Population-level models achieved low accuracy in predicting endpoints such as PEF < 65%. Subgroups related to specific allergies, asthma triggers, asthma types, and exacerbation treatments demonstrated high accuracy, with the most accurate, predictive endpoint being >4 SABA puffs/day/48 h. Individual models, constructed for patients with high endpoint overlap, exhibited significant predictive accuracy, especially for PEF < 65% and >4 SABA puffs/day/48 h. CONCLUSION: This multidimensional dataset enabled population-, subgroup-, and individual-level analyses, providing proof-of-concept evidence for development of predictive models of fluctuating asthma control.
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Asma , Estudo de Prova de Conceito , Humanos , Asma/fisiopatologia , Asma/tratamento farmacológico , Asma/diagnóstico , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Estudos Prospectivos , Algoritmos , Medidas de Resultados Relatados pelo Paciente , Estados Unidos , Aplicativos Móveis , Idoso , Administração por Inalação , Espirometria , Resultado do Tratamento , Adulto Jovem , Valor Preditivo dos Testes , Antiasmáticos/administração & dosagem , Antiasmáticos/uso terapêutico , Volume Expiratório Forçado , Nebulizadores e Vaporizadores , Fatores de Tempo , Adolescente , Índice de Gravidade de Doença , Pulmão/fisiopatologia , Pico do Fluxo ExpiratórioRESUMO
Division and differentiation events by which cell populations with specific functions are generated often take place as part of a developmental programme, which can be represented by a sequence of compartments. A compartment is the set of cells with common characteristics; sharing, for instance, a spatial location or a phenotype. Differentiation events are transitions from one compartment to the next. Cells may also die or divide. We consider three different types of division events: (i) where both daughter cells inherit the mother's phenotype (self-renewal), (ii) where only one of the daughters changes phenotype (asymmetric division), and (iii) where both daughters change phenotype (symmetric division). The self-renewal probability in each compartment determines whether the progeny of a single cell, moving through the sequence of compartments, is finite or grows without bound. We analyse the progeny stochastic dynamics with probability generating functions. In the case of self-renewal, by following one of the daughters after any division event, we may construct lifelines containing only one cell at any time. We analyse the number of divisions along such lines, and the compartment where lines terminate with a death event. Analysis and numerical simulations are applied to a five-compartment model of the gradual differentiation of hematopoietic stem cells and to a model of thymocyte development: from pre-double positive to single positive (SP) cells with a bifurcation to either SP4 or SP8 in the last compartment of the sequence.
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Diferenciação Celular , Divisão Celular , Processos Estocásticos , Autorrenovação Celular , Divisão Celular Assimétrica , Modelos Biológicos , Animais , Humanos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/fisiologiaRESUMO
Mucoepidermoid carcinoma is a type of salivary gland cancer that can develop in the context of a parotid gland cyst. This type of tumor is composed of mucous, epidermoid, and intercalated cells, and usually presents as a slow-growing and painless mass. A parotid gland cyst is a condition in which a fluid-filled sac forms in the parotid gland. The tumor can be masked as it develops within the parotid cyst. A 45-year-old female patient presented with a suspect of benign neoplasm of the major salivary gland. She underwent partial right parotidectomy, which upon pathological analysis confirmed the diagnosis of mucoepidermoid microcarcinoma associated with parotid gland cysts. The patient did well and continues under regular follow-up with no further treatment.
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BACKGROUND: TRAVERSE (NCT02134028), a phase 3 open-label extension study, assessed dupilumab safety and efficacy in patients with asthma aged ≥12 years who completed a previous dupilumab asthma study. This analysis evaluated changes in multiple lung function parameters in patients with moderate-to-severe asthma with elevated type 2 biomarkers (baseline eosinophils ≥150 cells·µL-1 or fractional exhaled nitric oxide ≥25 ppb) who completed QUEST (parent study) and 2 years of dupilumab treatment in TRAVERSE. METHODS: Endpoints analyzed included: pre-bronchodilator forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), forced expiratory flow (FEF25-75 %), and pre- and post-bronchodilator FEV1/FVC at parent study baseline (PSBL) at Weeks 0, 2, 48, and 96 in TRAVERSE, as well as pre- and post-bronchodilator FEV1 slopes in QUEST and TRAVERSE. Statistical analyses were descriptive. RESULTS: Dupilumab improved pre-bronchodilator FEV1, FVC, and FEF25-75 % in QUEST; these improvements were sustained in TRAVERSE. In QUEST patients who received placebo, dupilumab initiation in TRAVERSE resulted in rapid lung function improvements. Mean (standard deviation) changes from PSBL at TRAVERSE Weeks 48 and 96 in pre-bronchodilator FEV1 were 0.52 (0.59) and 0.45 (0.49) L in the dupilumab/dupilumab group and 0.47 (0.42) and 0.44 L (0.45) in the placebo/dupilumab group, respectively. Similar trends were observed for FVC and FEF25-75 %. Dupilumab also improved FEV1 slopes in QUEST and TRAVERSE. CONCLUSION: Dupilumab demonstrated sustained improvements across multiple spirometric lung function measurements for up to 3 years; patients who received placebo in QUEST experienced rapid lung function improvement upon initiation of dupilumab in TRAVERSE.