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1.
J Hazard Mater ; 416: 125790, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33862484

RESUMO

Ambient air pollution is a major risk factor for the prevalence and exacerbation of chronic obstructive pulmonary disease (COPD). Based on the COPDB (COPD in Beijing) panel study, whole-blood transcriptomes were repeatedly measured in 48 COPD patients and 62 healthy participants. Ambient mass concentrations of fine particulate matter (PM2.5), temperature, and relative humidity were continuously monitored at a monitoring station. The linear mixed-effects models were applied to estimate the associations between logarithmically transformed transcript levels and 1-day (d), 7-d, and 14-d average concentrations of PM2.5 before the start of follow-up visits. MetaCore™ was used to conduct the pathway enrichment analyses. Exposure to 1-, 7-, and 14-d average concentrations of PM2.5 was significantly associated with the transcriptome responses in both groups. The top 10, top 100, and top 1000 PM2.5-associated transcripts differed greatly between the two groups. Among COPD patients, role of alpha-6/beta-4 integrins in carcinoma progression, Notch signaling in breast cancer, and ubiquinone metabolism were the most significantly enriched PM2.5-associated biological pathways in the three time windows, respectively. In healthy participants, pro-opiomelanocortin processing was the most significant PM2.5-associated biological pathway in all three time windows. Our findings provide novel insights into the adverse health effects of air pollution exposure.

2.
Front Immunol ; 12: 653198, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912178

RESUMO

Interleukin (IL)-35-secreting B (IL-35+B) cells are critical regulators in autoimmune and infectious diseases and exert suppressive functions in parallel with IL-10-producing B (B10) cells. However, the role of IL-35+B cells in persistent hepatitis B virus (HBV) infection remains unclear. To elucidate the role of IL-35+B cells in the progress of chronic HBV infection, we determined the frequency of IL-35+B cells and their relationship with the classical human regulatory B cell (Breg) subsets, namely, CD19+CD24hiCD38hi and CD19+CD24hiCD27+. Then, the regulatory effect and mechanism of Bregs on effector T cells were investigated in vitro. Here, we found that compared with healthy controls, the frequency of IL-35+B cells was increased in patients with chronic HBV infection and was enriched in human classical Breg subset CD19+CD24hiCD38hi B cells. Moderate correlation was observed between the frequency of IL-35+B cells and alanine aminotransferase levels (Spearman r = 0.401), but only mild correlation was noted between the frequency of IL-35+B cells and HBV DNA level (Spearman r = 0.314). The frequency of IL-35+B cells was negatively correlated with interferon-γ (IFN-γ)-producing CD4+ and CD8+ cells but positively correlated with IL-4-producing T cells. Bregs dysregulated T cell function through an IL-35-dependent mechanism and depended on cell-to-cell contact. In conclusion, IL-35+ B cell was enriched in CD19+CD24hiCD38hi B cell subset during persistent HBV infection and Breg cells exerted dysregulation in T cell function through IL-35 dependent mechanism and depend on cell-to-cell contact. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT03734783.

3.
Sci Rep ; 11(1): 8694, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888748

RESUMO

Social and mental stressors associated with the pandemic of a novel infectious disease, e.g., COVID-19 or SARS may promote long-term effects on child development. However, reports aimed at identifying the relationship between pandemics and child health are limited. A retrospective study was conducted to associate the SARS pandemic in 2003 with development milestones or physical examinations among longitudinal measurements of 14,647 children. Experiencing SARS during childhood was associated with delayed milestones, with hazard ratios of 3.17 (95% confidence intervals CI: 2.71, 3.70), 3.98 (3.50, 4.53), 4.96 (4.48, 5.49), or 5.57 (5.00, 6.20) for walking independently, saying a complete sentence, counting 0-10, and undressing him/herself for urination, respectively. These results suggest relevant impacts from COVID-19 on child development should be investigated.


Assuntos
/psicologia , Desenvolvimento Infantil , Síndrome Respiratória Aguda Grave/psicologia , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos
4.
Sci Total Environ ; 782: 146804, 2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33838373

RESUMO

The temporal and spatial characteristics of turbulent transfer and diffusion coefficient of PM2.5 (KC) were investigated by determining the deviation, turbulent flux and form of universal function of PM2.5 mass concentrations. Turbulence and sounding observations from December 8-25, 2019, of three sites, Tuonan, Baoding, and Renqiu stations in the North China Plain were selected. Mean PM2.5 mass fluxes during the intensive observational period of three stations were negative. The spatial distribution of PM2.5 mass flux of three stations showed no obvious tendency. Then, the fact that PM2.5 mass concentrations satisfied the Monin-Obukhov similarity were reconfirmed by examining the relationship between the normalized standard deviation of PM2.5 mass concentrations and stability factor ζ. Thus, the universal functions in the three stations were achieved. The time series and profiles of KC in the three stations were also shown. There was a good inverse correlation between KC and PM2.5 mass concentration which suggested that the influence of turbulent diffusion is remarkably important during observational time even the emission, deposition, secondary transformation can all affect the change of mass concentrations of PM2.5 in the ABL. Changes in KC obviously presented diurnal characteristics. The comparisons of KC and KM and KH suggested that the strength of turbulent PM2.5 mass flux exchange could be weaker or stronger than the strength of turbulent momentum and heat flux exchange at different stations. The magnitude relationship between KC and KH could not be completely determined, so there were limitations in using KH to replace directly KC in the existing numerical weather or climate models. Finally, the spatial distribution of KC at the three stations presented almost symmetrical characteristics from east to west (Tuonan to Renqiu); that is, Baoding always had the lowest KC, and Tuonan and Renqiu stations had higher KCs. The spatial distribution of KC at the three stations corresponded well with that of PM2.5 mass concentrations, and Baoding always had the largest PM2.5 mass concentrations.

6.
Phys Chem Chem Phys ; 23(17): 10636-10649, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33904542

RESUMO

Recently, RNA aptamers activating small-molecule fluorophores have been successfully applied to tag and track RNAs in vivo. It is of significance to investigate the molecular mechanism of the fluorophore-RNA aptamer bindings at the atomic level to seek a possible pathway to enhance the fluorescence efficiency of fluorophores. In this work, multiple replica molecular dynamics (MRMD) simulations, essential dynamics (ED) analysis, and hierarchical clustering analysis were coupled to probe the effect of A22U mutation on the binding of two fluorophores, TO1-Biotin (TO1) and TO3-Biotin (TO3), to the Mango-II RNA aptamer (Mango-II). ED analysis reveals that A22U induces alterations in the binding pocket and sites of TO1 and TO3 to the Mango-II, which in turn tunes the fluorophore-RNA interface and changes the interactions of TO1 and TO3 with separate nucleotides of Mango-II. Dynamics analyses also uncover that A22U exerts the opposite impact on the molecular surface areas of the Mango-II and sugar puckers of nucleotides 22 and 23 in Mango-II complexed with TO1 and TO3. Moreover, the calculations of binding free energies suggest that A22U strengthens the binding ability of TO1 to the mutated Mango-II but weakens TO3 to the mutated Mango-II when compared with WT. These findings imply that point mutation in nucleotides possibly tune the fluorescence of fluorophores binding to RNA aptamers, providing a possible scheme to enhance the fluorescence of fluorophores.

7.
Environ Sci Technol ; 55(8): 4410-4419, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33793220

RESUMO

Nitrated phenols (NPs) are important atmospheric pollutants that affect air quality, radiation, and health. The recent development of the time-of-flight chemical ionization mass spectrometer (ToF-CIMS) allows quantitative online measurements of NPs for a better understanding of their sources and environmental impacts. Herein, we deployed nitrate ions as reagent ions in the ToF-CIMS and quantified six classes of gaseous NPs in Beijing. The concentrations of NPs are in the range of 1 to 520 ng m-3. Nitrophenol (NPh) has the greatest mean concentration. Dinitrophenol (DNP) shows the greatest haze-to-clean concentration ratio, which may be associated with aqueous production. The high concentrations and distinct diurnal profiles of NPs indicate a strong secondary formation to overweigh losses, driven by high emissions of precursors, strong oxidative capacity, and high NOx levels. The budget analysis on the basis of our measurements and box-model calculations suggest a minor role of the photolysis of NPs (<1 ppb h-1) in producing OH radicals. NPs therefore cannot explain the underestimated OH production in urban environments. Discrepancies between these results and the laboratory measurements of the NP photolysis rates indicate the need for further studies aimed at understanding the production and losses of NPs in polluted urban environments.


Assuntos
Poluentes Atmosféricos , Nitratos , Poluentes Atmosféricos/análise , Pequim , Monitoramento Ambiental , Gases/análise , Fenóis/análise
8.
Materials (Basel) ; 14(6)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808892

RESUMO

We added microencapsulated phase change materials (MPCMs) into the homemade antifreeze fluid to take advantage of the latent heat of phase change materials, and explored the possibility of solving the cold start problem of proton exchange membrane fuel cells (PEMFC) with variable specific heat capacity antifreeze. The physical and chemical properties of the MPCMs and their suspensions were tested, and a PEMFC platform for cold start with a thermal management system was established to compare the exothermic performance of MPCS and commercial antifreeze fluid. According to the output voltage, temperature and polarization curves before and after cold start, the MPCMs has a stronger heat transfer capacity than the commercial antifreeze fluid, and the addition of MPCMs can transform the latent heat generated during the phase transition into apparent specific heat capacity, leading to a better solution to the problem of PEMFC cold start.

10.
Korean J Pain ; 34(2): 210-216, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33785673

RESUMO

Background: Postherpetic neuralgia (PHN) is the most common complication of acute herpes zoster. The treatment of PHN remains a challenge for clinical pain management. Despite the effectiveness of anticonvulsants, antidepressants, and lidocaine patches in reducing PHN, many patients still face intractable pain disorders. In this randomized controlled study, we evaluated whether hydromorphone through intravenous patient-controlled analgesia (IV PCA) was effective in relieving PHN. Methods: Patients with PHN were randomly divided into two groups, one group received oral pregabalin with IV normal saline, another group received oral pregabalin with additional IV PCA hydromorphone for two weeks. Efficacy was evaluated at 1, 4, and 12 weeks after the end of the treatments. Results: Two hundred and one patients were followed up for 12 weeks. After treatment, numerical rating scale (NRS) score of patients in the hydromorphone group was significantly lower than that of the control group, and the difference of NRS scores between the two groups was statistically significant at 4 and 12 weeks after treatment. The frequency of breakthrough pain in the hydromorphone group was significantly lower than that in the control group 1 and 4 weeks after treatment. After treatment, the quality of sleep in the hydromorphone group was significantly improved compared with the control group. The most common adverse reactions in the hydromorphone group were dizziness and nausea, with no significant respiratory depression. Conclusions: IV PCA hydromorphone combined with oral pregabalin provides superior pain relief in patients with PHN, which is worthy of clinical application and promotion.

11.
Int J Epidemiol ; 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33787881

RESUMO

BACKGROUND: The role of smoking in nasopharyngeal carcinoma (NPC) remains uncertain, especially in endemic regions. We conducted an individual participant data (IPD) meta-analysis of prospective cohort studies to investigate the associations between smoking exposure and risk of NPC. METHODS: We obtained individual participant data of 334 935 male participants from six eligible population-based cohorts in NPC-endemic regions, including two each in Guangzhou and Taiwan, and one each in Hong Kong and Singapore. We used one- and two-stage approaches IPD meta-analysis and Cox proportional hazard models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of NPC for smoking exposure adjusting for age and drinking status. RESULTS: During 2 961 315 person-years of follow-up, 399 NPC evens were ascertained. Risks of NPC were higher in ever versus never smokers (HRone-stage = 1.32, 95% CI = 1.07-1.63, P = 0.0088; HRtwo-stage = 1.27, 1.01-1.60, 0.04). These positive associations appeared to be stronger in ever smokers who consumed 16+ cigarettes/day (HRone-stage = 1.67, 95% CI = 1.29-2.16, P = 0.0001), and in those who started smoking at age younger than 16 (2.16, 1.33-3.50, 0.0103), with dose-response relationships (P-values for trend = 0.0028 and 0.0103, respectively). Quitting (versus daily smoking) showed a small reduced risk (stopped for 5+ years: HRone-stage = 0.91, 95% CI = 0.60-1.39, P = 0.66; for former smokers: HRtwo-stage = 0.84, 0.61-1.14, 0.26). CONCLUSIONS: This first IPD meta-analysis from six prospective cohorts in endemic regions has provided robust observational evidence that smoking increased NPC risk in men. NPC should be added to the 12-16 cancer sites known to be tobacco-related cancers. Strong tobacco control policies, preventing young individuals from smoking, would reduce NPC risk in endemic regions.

12.
Environ Int ; 151: 106454, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33676285

RESUMO

BACKGROUND: Although epidemiological studies on the effect of chronic fine particulate matter (PM2.5) exposure on lipid disorders have been conducted, it is unclear if improved air quality is associated with beneficial changes in the blood lipid profile. In China, clean air actions introduced in 2013 have rapidly reduced the concentration of ambient PM2.5. METHODS: We conducted a change-by-change study, based on two waves (2011 and 2015) of a national survey of the same 5111 Chinese adults before and after implementation of the clean air actions. Long-term PM2.5 exposure was assessed using a state-of-the-art estimator at the city level. Based on the within-individual differences between the two waves, we associated PM2.5 changes with the variations of four lipid biomarkers-triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)-using a mixed-effects regression model. The robustness and homogeneity of the association were tested via sensitivity analyses. RESULTS: For each 10 µg/m3 reduction in PM2.5, LDL-C, and TC decreased by 2.71 (95% confidence interval [CI] 0.10-5.32) and 4.16 (95% CI 1.24-7.08)mg/dL, respectively. There was no significant association with HDL-C or TG. The results were robust among models adjusted for different covariates. PM2.5 was a significant risk factor for dyslipidemia with an adjusted relative risk of 1.21 (95% CI 1.09-1.34). The association between PM2.5 and LDL-C was stronger in the elderly or adults who did not take medications. CONCLUSIONS: The results suggest that PM2.5 exert a cardiotoxic effect by increasing the risk of lipid disorders. Improvement of air quality could prevent dyslipidemia by reducing LDL-C and TC levels. Clean air policies should be implemented as public health measures in countries with aging societies, especially developing ones with a high air pollution burden.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Adulto , Idoso , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , China , Cidades , Exposição Ambiental/análise , Humanos , Lipídeos , Material Particulado/análise
13.
Environ Sci Technol ; 55(8): 5097-5105, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33683876

RESUMO

Emerging epidemiological evidence has associated exposure to polycyclic aromatic hydrocarbons (PAHs) with chronic diseases including cardiometabolic diseases and neurodegeneration. However, little information is available about their subacute effects, which may accumulate over years and contribute to chronic disease development. To fill this knowledge gap, we designed a natural experiment among 26 healthy young adults who were exposed to elevated PAHs for 10 weeks after traveling from Los Angeles to Beijing in 2014 and 2015. Serum was collected before, during, and after the trip for metabolomics analysis. We identified 50 metabolites that significantly changed 6-8 weeks after the travel to Beijing (FDR < 5%). The network analysis revealed two main independent modules. Module 1 was allocated to oxidative homeostasis-related response and module 2 to delayed enzymatic deinduction response. Remarkably, the module 1 metabolites were recovered 4-7 weeks after participants' return, while the module 2 metabolites were not. Urinary hydroxylated PAHs were significantly associated with metabolites from both modules, while PAH carboxylic acids, likely metabolites of alkylated PAHs, were only associated with antioxidation-related metabolites. These results suggested differential subacute effects of unsubstituted and alkylated PAHs. Further studies are warranted to elucidate the role of the reversibility of metabolite changes in adverse health effects of PAHs.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Pequim , Ácidos Carboxílicos , Humanos , Los Angeles , Metabolômica , Hidrocarbonetos Policíclicos Aromáticos/análise , Adulto Jovem
14.
Environ Pollut ; 277: 116770, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33640815

RESUMO

Ambient air pollution is one of the leading environmental risk factors to human health, largely offsetting economic growth. This study evaluated health burden and cost associated with the short-term and long-term exposure of major air pollutants (fine particulate matter [PM2.5] and ozone [O3]) during 2013-2018. We developed a database of gridded daily and annual PM2.5 and O3 exposure in China at 15 km × 15 km resolution. Then, we estimated the age- and cause-specific premature deaths and quantified related health damage with an age-adjusted value of statistical life (VSL) measure. The health cost estimated in this study captured direct cost, indirect cost and intangible cost of the premature death attributable to ambient PM2.5 and O3. We found that the national premature deaths attributable to long-term and short-term exposure to PM2.5 decreased by 15% and 59%, whereas the national premature deaths attributable to long-term and short-term exposure to O3 increased by 36% and 94%. Despite a 15% reduction of attributable deaths, the health cost attributable to long-term exposure to PM2.5 did not change significantly as a result of GDP growth and population aging. On the other hand, the long-term O3 related health cost in 2018 doubled that in 2013. Our study suggests that while premature deaths fell as a result of China's clean air actions, the health costs of air pollution remained high. The growing trends of O3 highlighted the needs for strategies to reduce both PM2.5 and O3 emissions, for the sake of public health and social well-being in China.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China/epidemiologia , Efeitos Psicossociais da Doença , Exposição Ambiental , Custos de Cuidados de Saúde , Humanos , Material Particulado/análise
15.
Biosens Bioelectron ; 178: 113036, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33548656

RESUMO

Recent advancements in super-resolution nanoscopy allowed the study of mitochondrial biology at nanoscale and boosted the understanding its correlated cellular processes those were previously poorly understood. Nevertheless, studying mitochondrial ultrastructure remains a challenge due to the lack of probes that could target specific mitochondrial substances (e.g. cristae or mtDNA) and survive under harsh super-resolution optical conditions. Herein, in this work, we have rationally constructed a pyridine-BODIPY (Py-BODIPY) derivative that could target mitochondrial membrane in living cells without interfering its physiological microenvironments. Furthermore, we found Py-BODIPY is a membrane potential independent probe, hence it is not limit to live-cell staining but also showed a strong internalization into pre-fixed and stimulus disrupted sample. Importantly, its cristae specificity and superb photostability allow the observation of mitochondrial dynamic nano-structures with an unprecedented resolution, allow demonstrating how mitochondrial 3D ultrastructure evolved under oxidative phosphorylation condition.

16.
Chemosphere ; 273: 129496, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33524758

RESUMO

Vermiremediation on improvement of antimony (Sb) and cadmium (Cd) contaminated soil was less reported. In this study, earthworm Eisenia fetida was exposed into soil spiked with Sb and Cd and their mixture for 30 days, and then we measured multiple soil enzyme activities and bacteria communities via enzymatic reaction and high-throughput sequencing of 16 S rRNA genes. The results showed that Sb and Cd at high treatment levels inhibited the activities of urease, neutral phosphatase and protease significantly, but earthworm could promote the activities of urease and neutral phosphatase by 17.75%-121.91% and 1.46%-118.97%, respectively. However, earthworms inhibited catalase and had no effect on protease. The Geometric Mean Index suggested that earthworms led to a higher soil biochemistry function. According to a taxonomic analysis, bacterial community structure predominantly consisted of phylum Proteobacteria, Actinobacteria, Firmicutes, etc. and class Gammaproteobacteria, Actinobacteria, Alphaproteobacteria, etc.; furthermore, Pielou index and Shannon index (Alpha diversity in the habitat) indicated that bacteria diversity and evenness increased in the presence of earthworms. The heating map revealed that earthworms made genus Sphingomonas, Flavobacterium, etc. and species Sphingomonas jaspsi, Conexibacter, etc. dominate. Overall, earthworm is a suitable remediation species to improve the ecological function of heavy metal polluted soil. However, the specific mechanism and causal relationship of how earthworm to control enzyme activity and bacteria community remained to be explored.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Antimônio , Cádmio/análise , Cádmio/toxicidade , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Sphingomonas
17.
Environ Pollut ; 271: 116128, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33421844

RESUMO

Organosilicons are widely used in consumer products and are ubiquitous in living environments. However, there is little systemic information on this group of pollutants in ambient particles. This study proposes a novel untargeted strategy based mainly on the mass difference of three silicon isotopes to screen organosilicon compounds from 2-year PM2.5 samples of Beijing using gas chromatography and high-resolution time-of-flight mass spectrometry. 61 organosilicons were filtered from 1019 peaks, and 35 ones were identified as organosiloxanes including 17 methylsiloxanes and 18 phenylmethylsiloxanes, of which 6 and 3 species were confirmed using reference standards, respectively. These organosiloxanes could be clustered into three groups: low-silicon-number methylsiloxanes, high-silicon-number methylsiloxanes, and phenylmethylsiloxanes. Low-silicon-number methylsiloxanes showed high abundance in the heating season but low abundance in the non-heating season, whereas high-silicon-number methylsiloxanes showed the opposite seasonal variation. This study provides a promising strategy for screening organosilicon compounds through an untargeted approach and gives insights for further investigation of the sources and health risks of organosiloxanes.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Pequim , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas , Material Particulado/análise , Estações do Ano
18.
Environ Int ; 147: 106361, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33401173

RESUMO

Corona virus disease 2019 has spread worldwide, and appropriate drug design and screening activities are required to overcome the associated pandemic. Using computational simulation, blockade mechanism of SARS-CoV-2 spike receptor binding domain (S RBD) and human angiotensin converting enzyme 2 (hACE2) was clarified based on interactions between RBD and hesperidin. Interactions between anti-SARS-CoV-2 drugs and therapy were investigated based on the binding energy and druggability of the compounds, and they exhibited negative correlations; the compounds were classified into eight common types of structures with highest activity. An anti-SARS-CoV-2 drug screening strategy based on blocking S RBD/hACE2 binding was established according to the first key change (interactions between hesperidin and S RBD/hACE2) vs the second key change (interactions between anti-SARS-CoV-2 drugs and RBD/hACE2) trends. Our findings provide valuable information on the mechanism of RBD/hACE2 binding and on the associated screening strategies for anti-SARS-CoV-2 drugs based on blocking mechanisms of pockets.


Assuntos
Preparações Farmacêuticas , Humanos , Peptidil Dipeptidase A , Glicoproteína da Espícula de Coronavírus
19.
Neural Comput Appl ; : 1-10, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33424133

RESUMO

To predict the mortality of patients with coronavirus disease 2019 (COVID-19). We collected clinical data of COVID-19 patients between January 18 and March 29 2020 in Wuhan, China . Gradient boosting decision tree (GBDT), logistic regression (LR) model, and simplified LR were built to predict the mortality of COVID-19. We also evaluated different models by computing area under curve (AUC), accuracy, positive predictive value (PPV), and negative predictive value (NPV) under fivefold cross-validation. A total of 2924 patients were included in our evaluation, with 257 (8.8%) died and 2667 (91.2%) survived during hospitalization. Upon admission, there were 21 (0.7%) mild cases, 2051 (70.1%) moderate case, 779 (26.6%) severe cases, and 73 (2.5%) critically severe cases. The GBDT model exhibited the highest fivefold AUC, which was 0.941, followed by LR (0.928) and LR-5 (0.913). The diagnostic accuracies of GBDT, LR, and LR-5 were 0.889, 0.868, and 0.887, respectively. In particular, the GBDT model demonstrated the highest sensitivity (0.899) and specificity (0.889). The NPV of all three models exceeded 97%, while their PPV values were relatively low, resulting in 0.381 for LR, 0.402 for LR-5, and 0.432 for GBDT. Regarding severe and critically severe cases, the GBDT model also performed the best with a fivefold AUC of 0.918. In the external validation test of the LR-5 model using 72 cases of COVID-19 from Brunei, leukomonocyte (%) turned to show the highest fivefold AUC (0.917), followed by urea (0.867), age (0.826), and SPO2 (0.704). The findings confirm that the mortality prediction performance of the GBDT is better than the LR models in confirmed cases of COVID-19. The performance comparison seems independent of disease severity. Supplementary Information: The online version contains supplementary material available at(10.1007/s00521-020-05592-1).

20.
Lancet Planet Health ; 5(1): e15-e24, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33421406

RESUMO

BACKGROUND: Maternal exposure to ambient particulate matter (PM2·5) is associated with pregnancy loss (ie, stillbirth and miscarriage). South Asia has the highest burden of pregnancy loss globally and is one of the most PM2·5 polluted regions in the world. However, knowledge of the relevant exposure-response function for mothers is insufficient. METHODS: In this epidemiological case-control study, we collected data from Demographic and Health Surveys from India, Pakistan, and Bangladesh for the period 1998-2016 for women who reported at least one pregnancy loss and one or more livebirths. We assessed ambient exposure during gestation with satellite-based PM2·5 measurements for the period. To derive the exposure-response function, we did a self-compared case-control study in which each case of pregnancy loss was compared with a successful livebirth control or controls by the same mother. Using the estimated exposure-response function, we quantified pregnancy losses attributable to PM2·5 in the region for the period 2000-16 using a standard risk assessment approach. FINDINGS: We assessed data for 34 197 mothers, who had at least one pregnancy loss and one or more livebirth, of whom 26 282 (76·9%) were from India, 4228 (12·4%) were from Pakistan, and 3687 (10·8%) were from Bangladesh. The 34 197 cases of pregnancy loss were matched with 76 282 livebirth controls. The mean level of PM2·5 exposure was 56·00 µg/m3 (SD 30·82) for cases and 54·57 µg/m3 (31·73) for controls. After adjustment for maternal age, non-linear terms for temperature and humidity, seasonal variation, and long-term trends, each 10 µg/m3 increment in PM2·5 was associated with an odds ratio for pregnancy loss of 1·03 (95% CI 1·02-1·05). According to the estimated non-linear exposure-response function by age and urban residence versus rural residence, for the period 2000-16, an estimated 349 681 (95% CI 152 932-489 493) pregnancy losses per year were attributed to ambient air exposure of more than 40 µg/m3 (the annual PM2·5 standard of India), accounting for 7·1% (95% CI 3·3-31·2) of the total annual pregnancy loss burden in south Asia for this period. However, our estimates could be biased because of the limitations of the data (eg, misclassification of induced and spontaneous pregnancy losses). INTERPRETATION: Our findings add to epidemiological evidence of the association between pregnancy loss and PM2·5. Suboptimal air quality contributes to a considerable fraction of total pregnancy loss in south Asia. Controlling PM2·5 pollution will promote maternal health in south Asia. FUNDING: Chinese Natural Science Foundation and Ministry of Science and Technology of China.

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