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1.
Intern Med ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38749731

RESUMO

A 59-year-old woman presented with a rash on the top part of her hands and pain in the wrist joint and was diagnosed with dermatomyositis complicated by interstitial pneumonia positive for anti-melanoma differentiation-associated gene 5 (MDA-5) antibody. However, the patient reported a severe headache following treatment with oral prednisolone and tacrolimus. Posterior reversible encephalopathy syndrome (PRES) was diagnosed based on the brain magnetic resonance imaging findings. Tacrolimus was discontinued, and mycophenolate mofetil was instead administered with a favorable outcome. Mycophenolate mofetil should therefore be considered as an alternative treatment for anti-MDA-5-positive interstitial lung disease in cases where calcineurin inhibitors cannot be used.

2.
Int J Rehabil Res ; 47(2): 103-109, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38618657

RESUMO

Objectively measured physical activity volume serves as a predictive factor for functional recovery in patients with stroke. Malnutrition, a frequent complication of stroke, may influence the relationship between physical activity and functional recovery. This study aimed to examine the association between physical activity volume and functional recovery in patients with stroke, stratified by their nutritional status. This multicenter prospective observational study included 209 patients with stroke admitted to two Japanese convalescent rehabilitation hospitals. Participants were categorized based on the geriatric nutritional risk index (GNRI) at admission [≥92, high GNRI group ( n  = 133); <92, low GNRI group ( n  = 76)]. Physical activity levels were measured as the duration of total physical activity (TPA), which is the sum of light-intensity physical activity and moderate-to-vigorous physical activity, using a triaxial accelerometer during the first 7 days after admission. Outcome measures are represented as the relative gain of the motor score on functional independence measure (M-FIM effectiveness) during the first month after admission. The multiple regression analysis, adjusting for age, sex, comorbidity, onset to admission intervals, motor paralysis, initial M-FIM, and cognitive FIM, showed that the duration of TPA in the first 7 days was significantly associated with the M-FIM effectiveness over the first month in both low GNRI [ B  = 0.12, 95% confidential intervals (CI) = 0.01; 0.24, P  = 0.049] and high GNRI group ( B  = 0.11, 95% CI = 0.01; 0.21, P  = 0.027). This study demonstrates a positive predictive association between early TPA level and functional recovery in stroke patients, irrespective of their nutritional status.


Assuntos
Exercício Físico , Estado Nutricional , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral , Humanos , Feminino , Masculino , Idoso , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Acidente Vascular Cerebral/fisiopatologia
3.
Environ Sci Technol ; 57(4): 1788-1796, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36652306

RESUMO

Continuous monitoring systems, consisting of multiple fixed sensors, are increasingly being deployed at oil and gas production sites to detect methane emissions. While these monitoring systems operate continuously, their efficiency in detecting emissions will depend on meteorological conditions, sensor detection limits, the number of sensors deployed, and sensor placement strategies. This work demonstrates an approach to assess the effectiveness of continuous sensor networks in detecting infinite-duration and fixed-duration emission events. The case studies examine a single idealized source and a group of nine different sources at varying heights and locations on a single pad. Using site-specific meteorological data and dispersion modeling, the emission detection performance is characterized. For these case studies, infinite-duration emission events are detected within 1 h to multiple days, depending on the number of sensors deployed. The percentage of fixed-duration emission events that are detected ranged from less than 10% to more than 90%, depending on the number of sources, emission release height, emission event duration, and the number of sensors deployed. While these results are specific to these case studies, the analysis framework described in this work can be broadly applied in the evaluation of continuous emission monitoring network designs.


Assuntos
Poluentes Atmosféricos , Metano , Metano/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Meteorologia , Gás Natural/análise
4.
Sci Rep ; 12(1): 18028, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36302843

RESUMO

Development of a method for detecting protein-protein interactions (PPIs) in living cells is important for therapeutic drug screening against various diseases including infectious diseases. We have recently developed a method named SOS localization-based interaction screening (SOLIS), in which we designed membrane-anchored and SOS-fused chimeric proteins, whose PPI-dependent association triggers membrane localization of the SOS-fused chimeric protein, activates the Ras/MAPK pathway, and induces cell growth. While SOLIS was able to detect relatively strong PPIs, further sensitivity was required for detecting intracellular endogenous PPIs typically having a micromolar order of dissociation constant (Kd). Here we develop high-sensitive SOLIS (H-SOLIS) that could universally detect PPIs with lower affinities. In order to improve the sensitivity, H-SOLIS introduces a heterodimeric helper interaction, in which addition of a small-molecule helper ligand could accommodate association of the two chimeric proteins and regulate the sensitivity. Four types of domain-peptide interactions having known Kd values are employed to examine the versatility and detection limit of H-SOLIS. Consequently, the heterodimer-inducible helper ligand dramatically enhances detection sensitivity, lowering the detection limit to a ten-micromolar order of Kd. Thus, H-SOLIS could be a platform to detect disease-related domain-peptide interactions for drug discovery screening.


Assuntos
Peptídeos , Mapeamento de Interação de Proteínas , Animais , Ligantes , Peptídeos/química , Proteínas Son Of Sevenless , Citoplasma , Proteínas Recombinantes de Fusão , Mapeamento de Interação de Proteínas/métodos , Mamíferos
5.
Intern Med ; 61(24): 3713-3717, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35598992

RESUMO

We herein report a 45-year-old-man with multiple foreign body granulomas in the lungs caused by polytetrafluoroethylene (PTFE). A mass in the right lower lobe of the lung and bilateral centrilobular lung nodules were found unexpectedly during the patient's visit to a hospital for a respiratory infection. The patient's occupation for 26 years involved spraying PTFE. A lung biopsy using bronchoscopy revealed granulomatous lesions and giant cells. The presence of fluorine in the granulomatous lesions was confirmed using an electron probe microanalyzer with wavelength dispersive spectrometer. Fluorine is a component of PTFE and is not found in normal lung tissue.


Assuntos
Pneumopatias , Doenças Profissionais , Humanos , Pessoa de Meia-Idade , Politetrafluoretileno/efeitos adversos , Flúor , Pneumopatias/etiologia , Pneumopatias/patologia , Doenças Profissionais/complicações , Pulmão/diagnóstico por imagem , Pulmão/patologia , Granuloma/patologia
7.
Sci Total Environ ; 829: 154277, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35276157

RESUMO

In comparing observation based methane emission estimates for oil and gas well sites to routine emissions reported in inventories, the time scale of the measurement should match the time scale over which the inventoried emissions are estimated. Since many measurements are of relatively short duration (seconds to hours), a tool is needed to estimate emissions over these time scales rather than the annual totals reported in most emission inventories. This work presents a tool for estimating routine emissions from oil and gas well sites at multiple time scales; emissions at well sites vary over time due to changes in oil and gas production rates, operating practices and operational modes at the sites. Distributions of routine emissions (expected and inventoried) from well sites are generally skewed, and the nature and degree to which the distributions are skewed depends on the time scales over which emissions are aggregated. Abnormal emissions can create additional skew in these distributions. At very short time scales (emissions aggregated over 1 min) case study distributions presented in this work are both skewed and bimodal, with the modes depending on whether liquid storage tanks are flashing at the time of the measurement and whether abnormal emissions are occurring. At longer time scales (emissions aggregated over 1 day) distributions of routine emissions simulated in this work can have multiple modes if short duration, high emission rate events, such as liquid unloadings or large abnormal emissions, occur at the site. Multiple applications of the methane emission estimation tool (MEET), developed in this work, are presented. These results emphasize the importance of developing detailed emission inventories, which incorporate operational data, when comparing measurements to routine emissions. The model described in this work supports such comparisons and is freely available.


Assuntos
Poluentes Atmosféricos , Campos de Petróleo e Gás , Poluentes Atmosféricos/análise , Metano/análise , Gás Natural/análise , Fatores de Tempo
8.
Int Arch Allergy Immunol ; 183(3): 289-297, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34657036

RESUMO

INTRODUCTION: Psychological disorders, such as depression, are markedly prevalent in patients with airway diseases. In this study, we assessed the effect of treatment with dupilumab, an IL-4 receptor α chain antibody, on depressive symptoms in a cohort of patients with asthma with eosinophilic chronic rhinosinusitis (ECRS). METHODS: The study participants, diagnosed with asthma and ECRS, were assessed for symptoms and quality of life (QOL) scores for asthma and ECRS and medications. The Patient Health Questionnaire-9 (PHQ-9) scores were used to evaluate the depressive state. The depressive symptoms were compared with asthma and ECRS symptoms both at the time of initiation and after 4 months of dupilumab treatment. RESULTS: Ultimately, 31 patients were included in the study. Most patients demonstrated a depressive state that was correlated with the nasal symptom score. In the evaluation 4 months after dupilumab treatment, the PHQ-9 score was significantly reduced, and the decrease was remarkable in patients whose nasal symptom score was reduced by 50% or more. Additionally, the PHQ-9 scores in patients with improved nasal and asthma symptoms were significantly reduced. DISCUSSION/CONCLUSION: Dupilumab may improve QOL in patients with bronchial asthma with ECRS by reducing depressive symptoms through the improvement of clinical symptoms.


Assuntos
Asma , Pólipos Nasais , Rinite , Sinusite , Anticorpos Monoclonais Humanizados , Asma/complicações , Asma/tratamento farmacológico , Asma/epidemiologia , Doença Crônica , Depressão , Humanos , Japão , Pólipos Nasais/tratamento farmacológico , Qualidade de Vida , Rinite/complicações , Rinite/diagnóstico , Rinite/tratamento farmacológico , Sinusite/complicações , Sinusite/diagnóstico , Sinusite/tratamento farmacológico
9.
Respir Med Case Rep ; 33: 101451, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34401290

RESUMO

A 70-year-old man, treated for asthma for 2 years and chronic sinusitis for several months, presented with fever, numbness in the lower limbs, heaviness in the head, gross hematuria, and black stools. He also had eosinophilia, elevated serum IgG4 levels, high levels of myeloperoxidase-anti-neutrophil cytoplasmic antibodies (MPO-ANCA), and pulmonary infiltrative shadows. Bronchoscopy revealed multiple white flattened lesions (white moss) on the airway mucosa, suggesting mycobacterial infection or malignancy. A biopsy from tracheal mucosa revealed airway inflammation with marked eosinophil infiltration. The patient was diagnosed with eosinophilic granulomatosis with polyangiitis (EGPA) and treated with steroids, and all findings improved. However, a year and a half after the initiation of treatment, eosinophils and IgE gradually increased; subjective symptoms, such as asthma symptoms and numbness in the lower limbs, worsened; and ANCA, which had been negative, turned positive. Therefore, we suspected disease relapse and anti-IL-5 antibody (mepolizumab) treatment was initiated. Thereafter, ANCA turned negative again, eosinophils and IgE normalized, and subjective symptoms decreased. The presence of airway mucosal lesions in EGPA is relatively rare, and we report this case as a valuable case owing to the interesting bronchoscopic findings that are worth comprehending as a respiratory physician.

10.
Environ Sci Technol ; 55(5): 3210-3218, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33576222

RESUMO

Atmospheric emissions from oil and gas production operations are composed of multiple hydrocarbons and can have large variations in composition. Accurate estimates of emission compositions are needed to estimate the fate and impacts of emissions and to attribute emissions to sources. This work presents a database, constructed with empirical data and thermodynamic models, that can be queried to estimate hydrocarbon compositions from emission sources present at oil and gas production sites. The database can be searched for matches using between two and seven well parameters as query inputs (gas-to-oil ratio, API gravity, separator pressure, separator temperature, methane molar fraction in produced gas, ethane molar fraction of produced gas, and propane molar fraction in produced gas). Database query performance was characterized by comparing returns from database queries to a test data set. Application of the database to well parameters for tens of thousands of wells in the Barnett, Eagle Ford, and Fayetteville production regions demonstrates variations in emission compositions. Ethane to methane ratio varies by more than an order of magnitude from well to well and source to source. VOC to methane ratios are comparable in variability to ethane to methane ratios for most emission sources, but have a higher variability for emissions from flashing of liquid hydrocarbon tanks.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Etano/análise , Hidrocarbonetos/análise , Metano/análise , Gás Natural , Campos de Petróleo e Gás , Poços de Água
11.
Arthritis Res Ther ; 22(1): 150, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32571393

RESUMO

BACKGROUND: There is evidence that the cause of primary osteoarthritis (OA) is related to the changes in subchondral bone; however, the influence of subchondral insufficiency fracture (SIF) of the femoral head on the degeneration of the hip joint and the prognostic factors related to joint degeneration remain unclear. The objectives of this study were (1) to investigate the natural history of joint space width after the occurrence of SIF and (2) to investigate the associations between joint space narrowing and bone metabolic markers as well as magnetic resonance imaging (MRI) among the patients with SIF. METHODS: Between January 2010 and December 2019, 238 patients in whom band pattern of the femoral head were observed on MRI visited Hokkaido University Hospital. Among these patients, 44 hips in 41 patients were diagnosed with SIF and eligible for this retrospective study. We evaluated the joint space width (JSW) of the hip on the radiograph obtained at the first and last visits, length of the band lesion on MRI, bone mineral density by dual-energy X-ray absorptiometry, and bone metabolism markers. Similarly, the factors associated with the necessity of surgery and the progression of the narrowing of the joint space were evaluated. RESULTS: Fifteen of the 44 hips required total hip arthroplasty (THA). A significant decrease was observed in the JSW from the first visit to the final follow-up. Changes in the JSW were associated with the length of band patterns, serum type 1 procollagen-N-propeptide (P1NP), and tartrate-resistant acid phosphatase 5b (TRACP-5b) during diagnosis. Additionally, bone metabolic markers tended to be associated with the length of the band pattern. CONCLUSIONS: SIF could cause joint space narrowing and hip OA. In addition to MRI findings as prognostic predictors of SIF, as previously described, bone metabolic markers were equally associated with changes in JSW, suggesting that these parameters could be useful in predicting the prognosis of SIF. Considering that bone metabolic markers trended to be associated with the length of band pattern, they might reflect the local severity.


Assuntos
Cabeça do Fêmur , Fraturas de Estresse , Cartilagem , Cabeça do Fêmur/diagnóstico por imagem , Articulação do Quadril , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos
12.
Am J Respir Cell Mol Biol ; 63(1): 57-66, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32182104

RESUMO

It is well known that the prevalence of asthma is higher in athletes, including Olympic athletes, than in the general population. In this study, we analyzed the mechanism of exercise-induced bronchoconstriction by using animal models of athlete asthma. Mice were made to exercise on a treadmill for a total duration of 1 week, 3 weeks, or 5 weeks. We analyzed airway responsiveness, BAL fluid, lung homogenates, and tissue histology for each period. In mice that were treated (i.e., the treatment model), treatments were administered from the fourth to the fifth week. We also collected induced sputum from human athletes with asthma and analyzed the supernatants. Airway responsiveness to methacholine was enhanced with repeated exercise stimulation, although the cell composition in BAL fluid did not change. Exercise induced hypertrophy of airway smooth muscle and subepithelial collagen deposition. Cysteinyl-leukotriene (Cys-LT) levels were significantly increased with exercise duration. Montelukast treatment significantly reduced airway hyperresponsiveness (AHR) and airway remodeling. Expression of PLA2G4 (phospholipase A2 group IV) and leukotriene C4 synthase in the airway epithelium was upregulated in the exercise model, and inhibition of PLA2 ameliorated AHR and airway remodeling, with associated lower levels of Cys-LTs. The levels of Cys-LTs in sputum from athletes did not differ between those with and without sputum eosinophilia. These data suggest that AHR and airway remodeling were caused by repeated and strenuous exercise. Cys-LTs from the airway epithelium, but not inflammatory cells, may play an important role in this mouse model.


Assuntos
Remodelação das Vias Aéreas/fisiologia , Broncoconstrição/fisiologia , Cisteína/metabolismo , Fosfolipases A2 do Grupo II/metabolismo , Leucotrienos/metabolismo , Condicionamento Físico Animal/fisiologia , Acetatos/farmacologia , Remodelação das Vias Aéreas/efeitos dos fármacos , Animais , Asma/tratamento farmacológico , Asma/metabolismo , Hiper-Reatividade Brônquica/tratamento farmacológico , Hiper-Reatividade Brônquica/metabolismo , Broncoconstrição/efeitos dos fármacos , Ciclopropanos , Feminino , Leucotrienos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Cloreto de Metacolina/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Quinolinas/farmacologia , Hipersensibilidade Respiratória/tratamento farmacológico , Hipersensibilidade Respiratória/metabolismo , Sulfetos
13.
Clin Rheumatol ; 39(7): 2171-2178, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32056068

RESUMO

INTRODUCTION/OBJECTIVES: Interstitial lung disease (ILD) is a significant cause of mortality among patients with dermatomyositis (DM) or polymyositis (PM). There are two subtypes of PM and DM often complicated with ILD: those with anti-aminoacyl-tRNA synthetase (anti-ARS) antibodies and those with anti-MDA-5-associated amyopathic DM (ADM). Our aim is to clarify the inflammatory and immunological differences between the disorders. METHODS: We retrospectively collected consecutive patients with anti-ARS-ILD and those with anti-MDA-5 antibody-positive ADM-ILD. The serum concentration of 38 cytokines was measured using a cytokine panel. The relative risks for anti-MDA-5 antibody-positive ADM-ILD were examined with univariate and multivariate logistic regression models. Spearman's rank correlation coefficient was calculated between cytokine levels and clinical parameters in the disease. Levels of cytokines were compared between anti-ARS-ILD and anti-MDA-5-positive ADM-ILD patients (alive or dead) using Dunnett's test. RESULTS: Twenty-three patients with anti-ARS-ILD and the same number of patients with anti-MDA-5-positive ADM-ILD were enrolled. The anti-MDA-5 group had poor survival (p = 0.025). Univariate logistic regression models showed that eotaxin, IL-10, IP-10, and MCP-1 were associated with the diagnosis of anti-MDA-5-positive ADM-ILD. Multivariate logistic regression models revealed that IP-10 was the most significantly associated (p = 0.001). Relationship analyses showed that IL-10 had significant positive correlations with CK (r = 0.5267, p = 0.009) and ferritin (r = 0.4528, p = 0.045). A comparison of the cytokine levels found that IP-10 was elevated in both patients who were alive and patients who had died with ADM-ILD compared with the levels in those with ARS-ILD (p = 0.003 and p = 0.001, respectively). CONCLUSIONS: Anti-MDA-5-positive ADM-ILD had poorer survival than anti-ARS-ILD. IP-10 seems to be most deeply involved in the pathophysiology of anti-MDA-5-associated ADM-ILD.Key Points• To clarify differences in the inflammatory and immunological features of anti-MDA-5-positive ADM-ILD and anti-ARS-ILD, we performed an observational study to measure serum cytokine concentrations before treatment using a multiplex immunoassay system.• Multivariate logistic regression models revealed that IP-10 was associated with the most significant relative risk for ADM-ILD with anti-MDA-5 antibodies.• Levels of IP-10 were elevated considerably in anti-MDA-5-positive survivors and nonsurvivors compared with the levels in anti-ARS patients.• These results suggest that IP-10 is the most deeply involved in the pathophysiology of anti-MDA-5-positive ADM-ILD.


Assuntos
Autoanticorpos/sangue , Quimiocina CXCL10/sangue , Dermatomiosite/imunologia , Doenças Pulmonares Intersticiais/imunologia , Polimiosite/imunologia , Idoso , Aminoacil-tRNA Sintetases/imunologia , Citocinas/sangue , Dermatomiosite/complicações , Feminino , Humanos , Helicase IFIH1 Induzida por Interferon/imunologia , Modelos Logísticos , Doenças Pulmonares Intersticiais/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Polimiosite/complicações , Prognóstico , Estudos Retrospectivos , Sobreviventes/estatística & dados numéricos
14.
Allergol Int ; 69(1): 61-65, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31420174

RESUMO

BACKGROUND: Adherence Starts with Knowledge-12 (ASK-12) is a useful indicator of drug adherence. In this study, we analyzed patient background including social and psychological factors in a low-adherence group of patients with asthma defined using ASK-12. METHODS: From a questionnaire survey for patients with asthma from the Niigata Prefecture, Japan, conducted in the fall of 2016, we enrolled patients who answered all ASK-12 items and underwent a measured respiratory function test within 1 year. The low-adherence group (ASK-12 ≥ 28) was compared with the control group (ASK-12 < 28), and we conducted a cluster analysis of the low-adherence group. RESULTS: There were 170 patients in the low-adherence group and 402 patients in the control group. There was a significant difference between age, gender, working status, smoking history, the percentage of forced expiratory volume in one second (%FEV1), asthma control test (ACT), and Patient Health Questionnaire-9 (PHQ-9) score between the two groups. Logistic analysis revealed that working status (working), % FEV1 (<90%), and PHQ-9 score (>5) were independent factors for the low-adherence group. The cluster analysis identified three clusters in the low-adherence group. Among these, one cluster was characterized by elderly males with chronic obstructive pulmonary disease and another by middle-aged nonsmoking females with a depression tendency, had problems with asthma control. CONCLUSIONS: Several factors were considered to be attributed to low drug-adherence. There were several phenotypes in the low-adherence population correlated with incomplete asthma control. Intervention with drug adherence should be a future goal for asthma treatment.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Adesão à Medicação/estatística & dados numéricos , Idoso , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
15.
Aging Clin Exp Res ; 32(10): 2073-2079, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31673992

RESUMO

OBJECTIVE: The aim of this study was to investigate the relationship between tongue muscle quality index, which was represented as tongue muscle pressure divided by tongue muscle mass, and swallowing speed in community-dwelling older women. METHODS: The inclusion criteria for this cross-sectional study were that participants be community-dwelling older women aged 65 years and above without dysphagia. The exclusion criteria were stroke and Parkinson's disease that directly cause dysphagia. We measured tongue muscle thickness and maximum tongue pressure and the tongue muscle quality index, which was defined as the maximum tongue pressure divided by tongue muscle thickness. We investigated swallowing speed via a 100 ml water swallowing test. To assess the relationship between tongue muscle characteristics and swallowing speed, we performed stepwise multiple regression analysis. RESULTS: Ninety-three participants were enrolled in this study (mean age: 84.2 ± 4.7 years). A stepwise multiple regression analysis showed that age (ß = - 0.292, p < 0.01) and tongue muscle quality index (ß = 0.267, p < 0.01) were related to swallowing speed. CONCLUSION: We found that tongue muscle quality index was related to swallowing speed in community-dwelling older women. According to our findings, it is possible that the tongue muscle quality index is a useful parameter for assessing swallowing speed in older women without dysphagia.


Assuntos
Transtornos de Deglutição , Deglutição , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Transtornos de Deglutição/diagnóstico por imagem , Feminino , Humanos , Vida Independente , Pressão , Língua/diagnóstico por imagem
17.
Environ Sci Technol ; 53(9): 5483-5492, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30912428

RESUMO

Spatially resolved emission inventories were used with an atmospheric dispersion model to predict ambient concentrations of methane, ethane, and propane in the Eagle Ford oil and gas production region in south central Texas; predicted concentrations were compared to ground level observations. Using a base case inventory, predicted median propane/ethane concentration ratios were 106% higher (95% CI: 83% higher-226% higher) than observations, while median ethane/methane concentration ratios were 112% higher (95% CI: 17% higher-228% higher) than observations. Predicted median propane and ethane concentrations were factors of 6.9 (95% CI: 3-15.2) and 3.4 (95% CI: 1.4-9) larger than observations, respectively. Predicted median methane concentrations were 7% higher (95% CI: 39% lower-37% higher) than observations. These comparisons indicate that sources of emissions with high propane/ethane ratios (condensate tank flashing) were likely overestimated in the inventories. Because sources of propane and ethane emissions are also sources of methane emissions, the results also suggest that sources of emissions with low ethane/methane ratios (midstream sources) were underestimated. This analysis demonstrates the value of using multiple light alkanes in attributing sources of methane emissions and evaluating the performance of methane emission inventories for oil and natural gas production regions.


Assuntos
Poluentes Atmosféricos , Alcanos , Etano , Metano , Gás Natural , Texas
18.
Environ Sci Technol ; 51(20): 12016-12026, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-28805050

RESUMO

A gridded inventory for emissions of methane, ethane, propane, and butanes from oil and gas sources in the Barnett Shale production region has been developed. This inventory extends previous spatially resolved inventories of emissions by characterizing the overall variability in emission magnitudes and the composition of emissions at an hourly time resolution. The inventory is divided into continuous and intermittent emission sources. Sources are defined as continuous if hourly averaged emissions are greater than zero in every hour; otherwise, they are classified as intermittent. In the Barnett Shale, intermittent sources accounted for 14-30% of the mean emissions for methane and 10-34% for ethane, leading to spatial and temporal variability in the location of hourly emissions. The combined variability due to intermittent sources and variability in emission factors can lead to wide confidence intervals in the magnitude and composition of time and location-specific emission inventories; therefore, including temporal and spatial variability in emission inventories is important when reconciling inventories and observations. Comparisons of individual aircraft measurement flights conducted in the Barnett Shale region versus the estimated emission rates for each flight from the emission inventory indicate agreement within the expected variability of the emission inventory for all flights for methane and for all but one flight for ethane.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos , Gás Natural , Sedimentos Geológicos , Metano
19.
Int Arch Allergy Immunol ; 167(3): 167-76, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26288279

RESUMO

BACKGROUND: Active suppression induced by regulatory T (Treg) cells is reported to be one of the mechanisms involved in oral tolerance. All-trans retinoic acid (ATRA) has been reported to affect Treg cell differentiation. The present study examined the effects of ATRA on the induction of oral tolerance in a murine model of bronchial asthma. METHODS: BALB/c mice were sensitized to and challenged with ovalbumin (OVA) through feeding followed by OVA challenges. In some study groups ATRA was orally administered concomitantly with OVA feeding either in the presence or absence of the retinoic acid receptor antagonist LE135. Lung CD4+ T cells were isolated from mice exposed to ATRA and/or OVA, and transferred to control mice. Airway hyperresponsiveness (AHR), cell counts and cytokine levels in bronchoalveolar lavage (BAL) fluid, and lung histology were assessed. RESULTS: Concomitant administration of ATRA with OVA ameliorated AHR, airway eosinophilia, elevation of cytokines in BAL fluid and goblet cell metaplasia. The proportion of Treg cells in the lungs was increased in mice treated with OVA and ATRA, as compared to those treated with OVA only. Transfer of lung CD4+ T cells from mice treated with OVA and ATRA induced suppression of AHR and airway inflammation. LE135 completely reversed the effects of ATRA on AHR, airway allergic inflammation and the number of Treg cells in the lungs. CONCLUSION: These data suggested that oral administration of ATRA with OVA had the potential to enhance oral tolerance in this murine model of bronchial asthma. These effects were mediated, at least in part, by Treg cell expansion.


Assuntos
Asma/imunologia , Tolerância Imunológica/efeitos dos fármacos , Tretinoína/farmacologia , Transferência Adotiva , Remodelação das Vias Aéreas/efeitos dos fármacos , Remodelação das Vias Aéreas/imunologia , Animais , Asma/patologia , Líquido da Lavagem Broncoalveolar/imunologia , Dibenzazepinas/administração & dosagem , Dibenzazepinas/farmacologia , Modelos Animais de Doenças , Feminino , Fatores de Transcrição Forkhead/metabolismo , Imunofenotipagem , Pulmão/imunologia , Pulmão/metabolismo , Camundongos , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
20.
Environ Sci Technol ; 49(6): 3966-73, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25723953

RESUMO

The combined emissions and air quality impacts of electricity generation in the Texas grid and natural gas production in the Eagle Ford shale were estimated at various natural gas price points for the power sector. The increased use of natural gas in the power sector, in place of coal-fired power generation, drove reductions in average daily maximum 8 h ozone concentration of 0.6-1.3 ppb in northeastern Texas for a high ozone episode used in air quality planning. The associated increase in Eagle Ford upstream oil and gas production nitrogen oxide (NOx) emissions caused an estimated local increase, in south Texas, of 0.3-0.7 ppb in the same ozone metric. In addition, the potential ozone impacts of Eagle Ford emissions on nearby urban areas were estimated. On the basis of evidence from this work and a previous study on the Barnett shale, the combined ozone impact of increased natural gas development and use in the power sector is likely to vary regionally and must be analyzed on a case by case basis.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Gás Natural/efeitos adversos , Indústria de Petróleo e Gás/estatística & dados numéricos , Ozônio/análise , Centrais Elétricas/estatística & dados numéricos , Gás Natural/economia , Óxidos de Nitrogênio/análise , Texas
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