Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 55
Filtrar
1.
ACS Appl Mater Interfaces ; 16(14): 17745-17756, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38523600

RESUMO

The increasing demand for the state-of-the-art electrochromic devices has received great interest in synthesizing Prussian blue (PB) nanoparticles with a uniform diameter that exhibit excellent electrochromism, electrochemistry, and cyclability. Herein, we report the controllable synthesis of sub-100 nm PB nanoparticles via the coprecipitation method. The diameter of PB nanoparticles can be modulated by adjusting the reactant concentration, the selection of a chelator, and their purification. The self-assembled nanogranular thin films, homogeneously fabricated by using optimized PB nanoparticles with an average diameter of 50 nm as building blocks via the blade coating technique enable excellent performance with a large optical modulation of 80% and a high coloration efficiency of 417.79 cm2 C-1. It is also demonstrated by in situ and ex situ observations that the nanogranular PB thin films possess outstanding structural and electrochemical reversibility. Furthermore, such nanogranular PB thin films can enjoy the enhanced long-term cycling stability of the PB-WO3 complementary electrochromic devices having a 91.4% optical contrast retention after 16,000 consecutive cycles. This work provides a newly and industrially compatible approach to producing a complementary electrochromic device with extraordinary durability for various practical applications.

2.
Polymers (Basel) ; 15(24)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38139986

RESUMO

The metallo-supramolecular polymer (MSP) is considered one of the most promising electrodes for electrochromic devices due to its intrinsically stable redox properties. Nevertheless, despite extensive work focusing on improving the electrochromic and electrochemical properties of MSPs, little experimental evidence exists from in-depth investigations on the anion-induced electrochromism of MSPs. Herein, Ru-based metallo-supramolecular polymer (polyRu) films with excellent electrochromic performance were fabricated through a novel electrochemical deposition method, and the electrochromic mechanism was further understood. The polyRu films possess fast reaction kinetics with a short switching time of 4.0 s (colored) and 2.8 s (bleached) and highly reversible redox properties due to the resulting impacts on the capacitive behaviors (containing surface, near-surface and intercalation pseudo-capacitance) of the perchlorate ions in the electrochromic process. Moreover, the electrochromic degradation of the polyRu films is considered to stem from the numerous nanopores in the film induced by ClO4- transport and the exchange of counter anions from Cl- to ClO4-. In addition, a physical model, revealing the transport of conduction ions and the evolution of the structure and properties of the polyRu film during the electrochromic process, is presented. It is observed that the charge balance of Ru3+ and Ru2+, achieved through the adsorption/desorption of ClO4- on the film, provides electrochromic and electrochemical reversibility to the polyRu film under positive/negative bias. Correspondingly, a transformation from polyRu·(Cl-)2n to polyRu·(ClO4-)x(Cl-)2n-x in the polyRu film is induced by a counter anion exchange from Cl- to ClO4-. Revealing the detailed perchlorate ion transfer kinetics and electrochromic mechanism in this film can offer new insights into the application of metallo-supramolecular polymers in electrochromic devices.

3.
New Microbiol ; 46(2): 186-195, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37247239

RESUMO

Currently, the infection of hypervirulent Klebsiella pneumoniae (hvKp) is becoming increasingly serious and the virulent mechanisms of hvKp are still not very clear. An effective gene-editing method for genes on hvKp virulence plasmid can help us reveal related virulent mechanisms. There are a few reports focusing on the methods mentioned above, however with certain limitations. In this work, we first constructed the pRE112-basing recombinant suicide plasmid to knock out or replace the genes in the hvKp virulence plasmid based on the principle of homology recombination. Results showed that the target virulent genes iucA, iucB, iroB, and rmpA2 on the hvKp virulence plasmid were scarlessly knocked out or replaced by marker genes, and mutant hvKp strains with the expected phenotypes were obtained. These indicated that we established an efficient gene-editing method for genes on hvKp virulence plasmid, which could help us explore the functions of these genes and reveal the virulent mechanisms of hvKp.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Humanos , Virulência/genética , Klebsiella pneumoniae/genética , Plasmídeos/genética , Infecções por Klebsiella/tratamento farmacológico , Antibacterianos/uso terapêutico
4.
Acta Trop ; 240: 106866, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36801451

RESUMO

BACKGROUND: Entamoeba infection-associated diseases (EIADs) in humans are a worldwide public health problem, but there is a lack of a global picture of EIADs, which is vital to prevention and control. METHODS: We applied 2019 Global Burden of Disease (GBD) data collected from multiple sources at global, national and regional levels. The disability-adjusted life years (DALYs) with corresponding 95% uncertainty intervals (95% UIs) were extracted as the main measure of the burden of EIADs. The Joinpoint regression model was used to estimate the trends of age-standardised DALY rates by age, sex, geographical region, and sociodemographic index (SDI). Besides, a generalized linear model was conducted to analyze the influence of sociodemographic factors on the DALY rate of EIADs. RESULTS: In 2019, there were 2,539,799 (95% UI 850,865-6,186,972) DALY cases attributable to Entamoeba infection, and the global age-standardised DALY rate of EIADs was 36.77/100,000 (95% UI: 12.03-90.49). Although over the past 30 years, the age-standardised DALY rate of EIADs presented significantly declining trends [average annual percent change (AAPC) = -3.79%, 95% CI: -4.05% - -3.53%], it has remained a heavy burden among the age group of <5 years (257.43/100,000, 95% UI: 67.73-676.78) and the low SDI regions (100.47/100,000, 95% UI: 32.27-249.09). The age-standardized DALY rate in high-income North America and Australia had an increasing trend (AAPC = 0.38%, 95% CI: 0.47% - 0.28% and 0.38%, 95% CI: 0.46% - 0.29%, respectively). Furthermore, the DALY rates in high SDI regions showed statistically significant increasing trends among the age groups of 14-49, 50-69 years and 70+ years, with AAPCs of 1.01% (95% CI: 0.87% - 1.15%), 1.58% (95% CI: 1.43% - 1.73%), and 2.93% (95% CI: 2.58% - 3.29%), respectively. CONCLUSIONS: Over the past 30 years, the burden of EIADs has declined significantly. However, it has still caused a high burden in the low SDI regions and the age group of <5 years. At the same time, in adults and the elderly of the high SDI regions, the increasing trends of Entamoeba infection-associated burden should also be given more attention.


Assuntos
Polipose Adenomatosa do Colo , Entamebíase , Adulto , Humanos , Idoso , Pré-Escolar , Adolescente , Anos de Vida Ajustados por Qualidade de Vida , Carga Global da Doença , Fatores Socioeconômicos , Saúde Global , Fatores de Risco
5.
Int J Infect Dis ; 125: 153-163, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36328290

RESUMO

OBJECTIVES: Influenza vaccination is an effective method for preventing influenza virus infection. Herein, we performed a meta-analysis to quantify global influenza vaccination rates (IVRs) and the factors influencing its uptake in the general population, individuals with chronic diseases, pregnant women, and healthcare workers. METHODS: Related articles were obtained from online databases and screened according to the inclusion criteria. The pooled IVRs were calculated using the random effects model. Subgroup analyses and multivariate meta-regression were performed to determine the factors associated with influenza vaccine uptake. RESULTS: We included 522 studies from 68 countries/regions. Most studies were conducted in the European region (247 studies), followed by the Western Pacific (135 studies) and American regions (100 studies). The IVRs with 95% confidence intervals (CIs) in the general population were lower (24.96%, 23.45%-26.50%) than in individuals with chronic diseases (41.65%, 40.08%-43.23%), healthcare workers (36.57%, 33.74%-39.44%), and pregnant women (25.92%, 23.18%-28.75%). The IVRs in high-income countries/regions were significantly higher than that in middle-income countries/regions. A free national or regional vaccination policy, perception of influenza vaccine efficacy and disease severity, a recommendation from healthcare workers, and having a history of influenza vaccination were positive factors for vaccine uptake (P <0.01). CONCLUSION: Overall, global IVRs were low, especially in the general population. The studies on the IVRs, especially for priority populations, should be strengthened in Eastern Mediterranean, South-East Asian, and African regions. Free vaccination policies and the dissemination of continuous awareness campaigns are effective measures to enhance vaccination uptake.


Assuntos
Vacinas contra Influenza , Influenza Humana , Humanos , Feminino , Gravidez , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Vacinação , Pessoal de Saúde , Gestantes
6.
J Med Virol ; 94(10): 4850-4859, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35739613

RESUMO

Mumps is an acute infectious disease that spreads widely around the world. The aim of this study was to investigate the epidemiological features and sociodemographic factors associated with mumps in mainland China from 2004 to 2018. Incidence data for mumps during the period 2004-2018 were collected from the Public Health Sciences Data Center of China. Joinpoint regression analysis was performed to explore the trends of mumps. Space-time clustering analysis was conducted to spatial and temporal aggregation areas of mumps. A generalized linear model was used to explore sociodemographic factors associated with the incidence of mumps. The average annual incidence of mumps was 21.44/100 000 in mainland China. It was increased dramatically during 2004-2012 (annual percentage change​ [​​​​​​APC] = 7.51, 95% confidence interval [CI]: 2.28-13.00). After 2012, it remained stable, however, significantly increased in intermediately developed regions from 2015 to 2018 (APC = 25.84, 95% CI: 3.59-52.86). The first-level spatial and temporal aggregation areas were distributed in Xinjiang, Gansu, Qinghai, Ningxia and Shaanxi, Tibet, Sichuan, Yunnan, Chongqing, Guizhou, and Guangxi, with gathering times from January 1, 2006 to December 31, 2012 (relative risk [RR] = 1.87, p < 0.001). The percentage of the population aged 0-14 years, number of health workers per capital, and number of passengers were found to be positively associated with the incidence of mumps. Overall, after 2012, the incidence of mumps in mainland China remained stable. High-risk periods, clusters of regions, and sociodemographic factors for mumps were identified, which will help the government develop the disease- and location-specific interventive measures.


Assuntos
Caxumba , China/epidemiologia , Humanos , Incidência , Caxumba/epidemiologia , Fatores Sociodemográficos , Tibet
7.
Sci Total Environ ; 827: 154267, 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35247413

RESUMO

Synthetic cannabinoids (SCs) could pose serious health risks to its users. It is necessary to monitor its community consumption. Wastewater-based epidemiology is a potentially useful approach in this regard. However, limited research has been conducted to investigate the occurrence of SCs in wastewater. In this study, liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was optimized to analyze 8 SCs and metabolites (in total 16 analytes) in wastewater. The limit of quantification for this method for certain analytes in wastewater was as low as 0.03 ng L-1. The validated method was used to examine the stability of the analytes under different conditions and to examine their occurrence in wastewater collected from 31 major cities across China. The overwhelming majority of the analytes were stable within 24 h, even at room temperature. However, 5-fluoro MDMB-PICA and MDMB-4en-PINACA butanoic acid metabolite showed significant degradation within 120 days even when stored at -20 °C or -80 °C. At least one cannabinoid or their metabolite was detected in 21 cities. In the city with the highest detection rate, at least one synthetic cannabinoid or metabolite was detected in 95% of samples of the city. MDMB-4en-PINACA butanoic acid metabolite had the highest detection frequency (in 13.4% of the samples). These results indicated that SCs were used in a significant number of Chinese cities. A few parent drugs (MDMB-4en-PINACA, ADB-BUTINACA, 5-fluoro MDMB-PICA, 4-fluoro MDMB-BUTINACA) were detected in a small fraction of wastewater samples, possibly due to release from manufacturing of these cannabinoids or illegal addition of electronic cigarettes.


Assuntos
Canabinoides , Sistemas Eletrônicos de Liberação de Nicotina , Ácido Butírico , Canabinoides/química , Cromatografia Líquida , Cidades , Espectrometria de Massas em Tandem , Águas Residuárias
8.
Food Chem ; 374: 131761, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34896946

RESUMO

A rapid, selective, and sensitive method was developed for the detection of carbendazim and thiabendazole in edible vegetable oil. Two benzimidazole analytes were pre-concentrated by magnetic solid phase extraction (MSPE) using flowerlike Ni-NiO composite as sorbents and followed by LC-MS/MS analysis. The flowerlike Ni-NiO composite sorbent displayed a high affinity towards benzimidazole analytes due to the reversible coordination interaction between the Ni(Ⅱ) ion and the electron-donating imidazole group. In comparison to the previous methods, this procedure is less time-consuming and simpler during sample preparation. The parameters affecting the extraction efficiency were optimized in detail. The method was validated according to SANTE/12682/2019. The limits of detection were in the range of 0.001-0.003 mg•kg-1. The recoveries ranged from 89.3% to 110.7% with inter-day and inter-day precision less than 10.9%. The results indicate that flowerlike Ni-NiO composite might be a promising alternative for MSPE of benzimidazole compounds in foods.


Assuntos
Tiabendazol , Verduras , Benzimidazóis/análise , Carbamatos , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Fenômenos Magnéticos , Óleos de Plantas , Extração em Fase Sólida , Espectrometria de Massas em Tandem
9.
Artigo em Inglês | MEDLINE | ID: mdl-34682386

RESUMO

The selection and spread of antibiotic resistance poses risks to public health by reducing the therapeutic potential of antibiotics against human pathogens. Wastewater-based epidemiology (WBE) is potentially the most reliable approach to estimate antibiotics use. Previous WBE studies used parent antibiotics as biomarkers, which may lead to overestimation since parent antibiotics may be directly disposed of. Using metabolites as biomarkers can avoid this drawback. This study developed a simultaneous solid-phase extraction coupled with ultra-high-performance liquid chromatography tandem mass spectrometry method for analyzing 12 antibiotics and human metabolites in wastewater to help assess health risk. Optimum conditions were achieved using a PEP cartridge at pH 3.0. The extraction efficiencies were 73.3~95.4% in influent and 72.0~102.7% in effluent for most of the target analytes. Method detection limit ranged from 0.1 to 1.5 ng/L for influent wastewater and 0.03 to 0.7 ng/L for effluent wastewater. A stability experiment showed that sulfonamide parents and their metabolites were stable at 4 °C, -20 °C and -80 °C, while macrolides metabolites were more stable than their corresponding parents at 4 °C and -20 °C. Finally, the method was applied to measure these analytes in wastewater samples collected from three Beijing WWTPs and to derive apparent removal rates. All metabolites were detected in wastewater samples with concentrations ranging from 1.2 to 772.2 ng/L in influent, from

Assuntos
Águas Residuárias , Poluentes Químicos da Água , Antibacterianos , Humanos , Laboratórios , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Águas Residuárias/análise , Poluentes Químicos da Água/análise
10.
PLoS One ; 16(9): e0256480, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34473738

RESUMO

BACKGROUND: The prevalence of pulmonary embolism (PE) in the acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) is highly controversial. We conducted a systematic review and meta-analysis to summarize the epidemiology and characteristics of PE with AE-COPD for current studies. METHODS: We searched the PubMed, EMBASE, Cochrane Library and Web of Science databases for studies published prior to October 21, 2020. Pooled proportions with 95% confidence intervals (95% CIs) were calculated using a random effects model. Odds ratios (ORs) and mean differences (MDs) with 95% confidence intervals were used as effect measures for dichotomous and continuous variables, respectively. RESULTS: A total of 17 studies involving 3170 patients were included. The prevalence of PE and deep vein thrombosis (DVT) in AE-COPD patients was 17.2% (95% CI: 13.4%-21.3%) and 7.1% (95% CI: 3.7%-11.4%%), respectively. Dyspnea (OR = 6.77, 95% CI: 1.97-23.22), pleuritic chest pain (OR = 3.25, 95% CI: 2.06-5.12), lower limb asymmetry or edema (OR = 2.46, 95% CI:1.51-4.00), higher heart rates (MD = 20.51, 95% CI: 4.95-36.08), longer hospital stays (MD = 3.66, 95% CI: 3.01-4.31) were associated with the PE in the AE-COPD patients. Levels of D-dimer (MD = 1.51, 95% CI: 0.80-2.23), WBC counts (MD = 1.42, 95% CI: 0.14-2.70) were significantly higher and levels of PaO2 was lower (MD = -17.20, 95% CI: -33.94- -0.45, P<0.05) in the AE-COPD with PE group. The AE-COPD with PE group had increased risk of fatal outcome than the AE-COPD group (OR = 2.23, 95% CI: 1.43-3.50). CONCLUSIONS: The prevalence of PE during AE-COPD varies considerably among the studies. AE-COPD patients with PE experienced an increased risk of death, especially among the ICU patients. Understanding the potential risk factors for PE may help clinicians identify AE-COPD patients at increased risk of PE. PROSPERO REGISTRATION NUMBER: CRD42021226568.


Assuntos
Dor no Peito/epidemiologia , Dispneia/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Edema Pulmonar/epidemiologia , Embolia Pulmonar/epidemiologia , Trombose Venosa/epidemiologia , Doença Aguda , Biomarcadores/sangue , Dor no Peito/patologia , Dispneia/patologia , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Humanos , Tempo de Internação/estatística & dados numéricos , Razão de Chances , Prevalência , Doença Pulmonar Obstrutiva Crônica/patologia , Edema Pulmonar/patologia , Embolia Pulmonar/patologia , Fatores de Risco , Trombose Venosa/patologia
11.
Front Public Health ; 9: 652842, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816427

RESUMO

Background: The viral shedding time (VST) of SARS-CoV-2 mainly determines its transmission and duration of infectiousness. However, it was heterogeneous in the existing studies. Here, we performed a meta-analysis to comprehensively summarize the VST of SARS-CoV-2. Methods: We searched PubMed, Web of Science, MedRxiv, BioRxiv, CNKI, CSTJ, and Wanfang up to October 25, 2020, for studies that reported VSTs of SARS-CoV-2. Pooled estimates and 95% CIs for the VSTs were calculated using log-transformed data. The VSTs in SARS-CoV-2 infections based on different demographic and clinical characteristics, treatments and specimens were stratified by subgroup analysis. Results: A total of 35 studies involving 3,385 participants met the inclusion criteria. The pooled mean VST was 16.8 days (95% CI: 14.8-19.4, I2 = 99.56%) in SARS-CoV-2 infections. The VST was significantly longer in symptomatic infections (19.7 days, 95% CI: 17.2-22.7, I2 = 99.34%) than in asymptomatic infections (10.9 days, 95% CI: 8.3-14.3, I2 = 98.89%) (P < 0.05). The VST was 23.2 days (95% CI: 19.0-28.4, I2 = 99.24%) in adults, which was significantly longer than that in children (9.9 days, 95% CI: 8.1-12.2, I2 = 85.74%) (P < 0.05). The VST was significantly longer in persons with chronic diseases (24.2 days, 95% CI: 19.2-30.2, I2 = 84.07%) than in those without chronic diseases (11.5 days, 95% CI: 5.3-25.0, I2 = 82.11%) (P < 0.05). Persons receiving corticosteroid treatment (28.3 days, 95% CI: 25.6-31.2, I2 = 0.00%) had a longer VST than those without corticosteroid treatment (16.2 days, 95% CI: 11.5-22.5, I2 = 92.27%) (P = 0.06). The VST was significantly longer in stool specimens (30.3 days, 95% CI: 23.1-39.2, I2 = 92.09%) than in respiratory tract specimens (17.5 days, 95% CI: 14.9-20.6, I2 = 99.67%) (P < 0.05). Conclusions: A longer VST was found in symptomatic infections, infected adults, persons with chronic diseases, and stool specimens.


Assuntos
COVID-19/virologia , SARS-CoV-2/fisiologia , Eliminação de Partículas Virais , Corticosteroides/uso terapêutico , Adulto , Infecções Assintomáticas , Criança , Comorbidade , Fezes/virologia , Humanos
12.
Int J Infect Dis ; 104: 458-464, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33444755

RESUMO

OBJECTIVES: The role of asymptomatic infections in the transmission of COVID-19 have drawn considerable attention. Here, we performed a meta-analysis to summarize the epidemiological and radiographical characteristics of asymptomatic infections associated with COVID-19. METHODS: Data on the epidemiological and radiographical characteristics of asymptomatic infections were extracted from the existing literature. Pooled proportions with 95% confidence intervals were then calculated using a random effects model. RESULTS: A total of 104 studies involving 20,152 cases were included. The proportion of asymptomatic individuals among those with COVID-19 was 13.34% (10.86%-16.29%), among which presymptomatic and covert infections accounted for 7.64% (4.02%-14.04%) and 8.44% (5.12%-13.62%), respectively. The proportions of asymptomatic infections among infected children and healthcare workers were 32.24% (23.08%-42.13%) and 36.96% (18.51%-60.21%), respectively. The proportion of asymptomatic infections was significantly higher after 2020/02/29 than before (33.53% vs 10.19%) and in non-Asian regions than in Asia (28.76% vs 11.54%). The median viral shedding duration of asymptomatic infections was 14.14 days (11.25-17.04). A total of 47.62% (31.13%-72.87%) of asymptomatic infections showed lung abnormalities, especially ground-glass opacity (41.11% 19.7%-85.79%). CONCLUSIONS: Asymptomatic infections were more commonly found in infected children and healthcare workers and increased after 2020/02/29 and in non-Asian regions. Chest radiographical imaging could be conducive to the early identification of asymptomatic infections.


Assuntos
Infecções Assintomáticas/epidemiologia , COVID-19/diagnóstico por imagem , COVID-19/epidemiologia , Eliminação de Partículas Virais , Humanos , Radiografia Torácica , SARS-CoV-2
13.
Int J Epidemiol ; 50(2): 527-537, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33517415

RESUMO

BACKGROUND: Although female sex workers (FSWs) have long been identified as a key human papillomavirus (HPV)-affected population, the burden and scope of their disproportionate risk for HPV infection have not been systematically estimated. We therefore aimed to estimate the prevalence of HPV and the distribution of HPV types in FSWs at the country, regional and global levels. METHODS: We searched the PubMed, Embase, SCOPUS, EBSCO, ProQuest, Cochrane Library and Web of Science databases for articles published between 1 January 1990 and 31 June 2019. Studies of genital HPV prevalence in FSWs, or with sufficient data (e.g. adequate number of HPV-positive cases and sample size) to compute prevalence rates in FSWs, were included in this systematic review. The meta-analysis was completed using the random effects model. RESULTS: We ultimately identified 107 studies in 45 countries or regions with sufficient data to calculate HPV prevalence in FSWs. The pooled global HPV prevalence among FSWs was 39.5% (95% CI 35.3, 43.9%), with notable variations by WHO region and country. Globally, the five most common HPV types in FSWs were HPV16 (9.0%), HPV 52 (8.3%), HPV89 (7.0%), HPV58 (6.2%), and HPV53 (5.3%). CONCLUSIONS: Our findings suggest that FSWs are disproportionately affected by HPV, which is more pronounced in the Western Pacific and African regions, and are therefore in need of prevention, treatment and care services.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Profissionais do Sexo , Feminino , Genitália , Humanos , Papillomaviridae , Infecções por Papillomavirus/epidemiologia , Prevalência
14.
Virus Res ; 291: 198186, 2021 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-33075446

RESUMO

Characterization of host adaptation markers among human isolates is important for recognizing the potential for cross-species transmission in avian influenza A viruses. Here, we studied two new potential adaptive mutations, V292I and D740A, in the PB2 protein that were identified by a multi-factor regression model. The study shows that the prevalence of the PB2-V292I mutation is increased in H7N9 influenza viruses isolated from both humans and birds over the past 6 years. The phylogenetic tree showed that influenza A/H7N9 has a lineage based on the strains containing PB2-292I. Polymerase complexes containing PB2-292I/627K derived from H7N9 exhibit increased polymerase activity. PB2-292I coupled with 627K also enhances viral transcription and replication in cells, whereas PB2-292I alone did not show the same effect in the H7N9 virus. However, PB2-740A only had a limited prevalence in 2013, and the change from D to A in PB2-740A may have a negative effect on the replication of the H7N9 virus in cells.


Assuntos
Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Mutação , Filogenia , RNA Polimerase Dependente de RNA/genética , Proteínas Virais/genética , Replicação Viral/genética , Células A549 , Animais , Aves/virologia , Cães , Células HEK293 , Humanos , Influenza Aviária/virologia , Influenza Humana/virologia , Células Madin Darby de Rim Canino , Replicação Viral/fisiologia
15.
J Chromatogr Sci ; 58(7): 678-685, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32548633

RESUMO

This paper reports a simple, sensitive and reliable method for the simultaneous detection of aflatoxin B1, B2, G1 and G2 in vegetable oils. Aflatoxins were extracted by magnetic solid phase extraction followed by high-performance liquid chromatography, then postcolumn photochemical derivatization and finally detected by fluorescence detector. Vegetable oil samples were first diluted with hexane and then commercial bare Fe3O4 nanoparticles were directly employed as sorbents to extract aflatoxins from complex vegetable oil samples, which significantly simplified the procedure of sample preparation and largely improved the sample analysis throughput. The effects of various parameters such as the amount of sorbent, loading, washing and eluting conditions were carefully optimized to improve the extraction efficiencies of aflatoxins. Under the optimal conditions, the limits of detection of four aflatoxins ranged from 0.01 µg/kg to 0.16 µg/kg, and squared regression coefficients (R2) >0.9990 were obtained within the linear range of 0.1-20 µg/kg (except for aflatoxin G2 with 0.5-20 µg/kg). Furthermore, the recoveries spiked at four concentration levels in a blank vegetable oil sample were from 82.6 to 106.2%, with inter- and intraday relative standard deviations <9.8%, indicating good accuracy and precision of the proposed method.


Assuntos
Aflatoxinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Nanopartículas de Magnetita/química , Óleos de Plantas/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
16.
Sci Rep ; 10(1): 3044, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080223

RESUMO

Influenza-related severe pneumonia and acute respiratory distress syndrome (ARDS) are severe threats to human health. The objective of this study was to assess the effects of systematic corticosteroid therapy in patients with pneumonia or ARDS. The PubMed, EMBASE, Web of Science and SCOPUS databases were searched up to July, 2019. Nineteen studies including 6637 individuals were identified, and fifteen studies (6427 patients) were included in the meta-analysis of mortality. Eighteen were observational studies and one was a randomized controlled trial (RCT). The meta-analysis results showed that corticosteroid therapy was associated with significantly higher mortality (OR 1.53, 95% CI [1.16, 2.01]) and incidence of nosocomial infection (OR 3.15, 95% CI [1.54, 6.45]). Subgroup analysis showed that among patients with unadjusted estimates, the odds of mortality were higher in patients receiving corticosteroid treatment (OR 1.98, 95% CI [1.23, 3.17]), however, among patients with adjusted estimates, the result showed no statistically significant difference between corticosteroid group and control group (OR 1.31, 95% CI [0.95, 1.80]). Current data do not support the routine use of corticosteroids in patients with influenza severe pneumonia or ARDS. RCTs are needed to provide more robust evidence.


Assuntos
Corticosteroides/uso terapêutico , Influenza Humana/tratamento farmacológico , Pneumonia/tratamento farmacológico , Pneumonia/virologia , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/virologia , Adolescente , Corticosteroides/farmacologia , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Infecção Hospitalar/induzido quimicamente , Feminino , Humanos , Influenza Humana/mortalidade , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Pneumonia/mortalidade , Respiração Artificial , Síndrome do Desconforto Respiratório/mortalidade , Fatores de Tempo , Resultado do Tratamento , Eliminação de Partículas Virais , Adulto Jovem
17.
Epidemiol Infect ; 148: e37, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32089144

RESUMO

This study aims to ascertain the long-term epidemic trends of malaria and evaluates the probability of achieving the eradication goal by 2020 in China. Data on malaria incidence and deaths were extracted from the China Information System for Disease Control and Prevention. The epidemic trends by sex, age and spatial distribution and predictions of malaria were estimated by using Joinpoint and Poisson regressions. From 1950 to 2016, 227 668 374 malaria cases were reported in China, with an annualised average incidence of 337.02 (336.98-337.07, 95% confidence interval (CI)) per 100 000 population. The incidence decreased with an average annual per cent change (AAPC) of -11.4% (-16.6 to -6.0). There were 36 085 malaria deaths, with an annualised average mortality of 0.534 (0.529-0.540) per 1 000 000 population. The mortality decreased with an AAPC of -8.7% (-13.7 to -3.4). The predicted number of malaria cases and deaths for 2020 is 2 562 and 10, respectively, and zero for indigenous cases. The disease burden of malaria dramatically decreased in China. Though, the goal of malaria elimination is realistic by 2020 in China, routine clinical and entomological surveillance should be continually conducted, especially for the cross-border areas and imported malaria cases.


Assuntos
Monitoramento Epidemiológico , Malária/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Estudos Longitudinais , Malária/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Distribuição por Sexo , Análise de Sobrevida , Topografia Médica , Adulto Jovem
18.
Vaccine ; 38(6): 1332-1344, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31948819

RESUMO

BACKGROUND: Children and adolescents are susceptible to influenza. Vaccination is the most important strategy for preventing influenza, yet there are few studies on the immunogenicity and safety of quadrivalent inactivated influenza vaccine (QIV) containing two A strains (H1N1 and H3N2) and two B lineages (Victoria and Yamagata). Therefore, to further clarify the immunogenicity and safety of QIV in children and adolescents, a meta-analysis was performed to provide a reference for the development of influenza prevention strategies. METHODS: PubMed, EMBASE and Cochrane Library were searched for articles published as of February 12, 2019. Random clinical trials comparing the immunogenicity and safety of QIV and TIV among children and adolescents were selected. The main outcomes were comparisons of immunogenicity (seroprotection rate [SPR] and seroconversion rate [SCR] and adverse events using risk ratios (RRs). The meta-analysis was performed using random-effects models. RESULTS: Among the 6 months up to 3 years group, QIV showed a higher SPR for B lineages than for TIV-B/Yamagata, with pooled RRs of 3.07 (95% CI: 2.58-3.66) and 1.06 (95% CI: 1.01-1.11), respectively. For the 3 years through 18 years, QIV had a higher SCR and SPR for the Yamagata lineage than for TIV-B/Victoria, with pooled RRs of 2.30 (95% CI: 1.83-2.88) and 1.16 (95% CI: 1.03-1.30), respectively. Compared to TIV-B/Yamagata, a higher SCR and SPR for the Victoria lineage was found for QIV, with RRs of 3.09 (95% CI: 1.99-4.78) and 1.72 (95% CI: 1.22-2.41), respectively. Regarding adverse events, only pain was more frequently reported for QIV than TIV ; the RR was 1.09 (95% CI: 1.02-1.17). CONCLUSIONS: The immunogenicity of QIV for common ingredients was similar to that of TIV, but the former exhibited significantly higher immunogenicity for the unique lineage. QIV also had the same reliable safety as TIV.


Assuntos
Imunogenicidade da Vacina , Vacinas contra Influenza/imunologia , Influenza Humana , Adolescente , Anticorpos Antivirais/imunologia , Criança , Testes de Inibição da Hemaglutinação , Humanos , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Vírus da Influenza B/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/classificação , Influenza Humana/prevenção & controle , Vacinas Combinadas , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia
19.
Liver Int ; 40(2): 298-307, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31674705

RESUMO

BACKGROUND & AIMS: Trends in long-term mortality rates for viral hepatitis in East and Southeast Asia have been rarely reported. The aim of our study was to explore the long-term trends in viral hepatitis mortality rates in East and Southeast Asian countries between 1987 and 2015 and provide predictions of mortality to 2030. METHODS: We obtained viral hepatitis mortality data from the WHO Mortality Database for six East and Southeast Asian countries between 1987 and 2015. We produced choropleth maps of viral hepatitis mortality rates in 1987 and 2015 in East and Southeast Asia to illustrate geographic variations. We made predictions of mortality rates for each included country until the year 2030 using a series of joinpoint models. RESULTS: Viral hepatitis mortality rates declined in China (the average annual percent change (AAPC) = -5.1%, 95% CI: -7.5, -2.6), Singapore (AAPC = -5.4%, 95% CI: -7.5, -3.2), and the Philippines (AAPC = -3.4%, 95% CI: -4.9, -1.8). In contrast, Japan, the Republic of Korea, and Malaysia have experienced increasing trends in mortality rates, followed by decreasing trends. Our predictions indicate that all countries will experience slight to moderate downward trends until 2030. CONCLUSION: Favourable decreasing trends have been noted in East and Southeast Asian countries, which may not only inform the control and management of viral hepatitis in this region but also guide the prevention of viral hepatitis deaths in another region with a similar viral hepatitis epidemic.


Assuntos
Hepatite Viral Humana , Sudeste Asiático/epidemiologia , China , Hepatite Viral Humana/epidemiologia , Humanos , Japão , Mortalidade , República da Coreia , Singapura
20.
BMC Infect Dis ; 19(1): 668, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31357951

RESUMO

BACKGROUND: A severe seasonal influenza epidemic was observed during 2017-2018 in China, prompting questions on clinical characteristics and outcomes of severe cases with influenza. METHODS: We retrospectively collected clinical data and outcomes of laboratory-confirmed hospitalized patients (severe to critical) during Jan-2011 to Feb-2018 from five hospitals, followed by a systematic analysis of cases from 2017 to 2018 (n = 289) and all previous epidemics during 2011-2017 (n = 169). RESULTS: In-hospital fatality was over 5-folds higher during the 2017-2018 (p < 0.01) in which 19 patients died (6.6%), whereas only 2 mortalities (1.2%) were observed during 2011-2017. Of the 289 hospitalized in 2017-2018, 153 were confirmed with influenza B virus, 110 with A/H1N1pdm09, and 26 A/H3N2, whereas A/H1N1pdm09 was the predominant cause of hospitalization in previous seasons combined (45%). Fatal cases in 2017-2018 were exclusively associated with either influenza B or A/H1N1pdm09. Our results show that a significant lower proportion of patients aged 14 or greater were treated with oseltamivir, during the 2017-2018 epidemic, and exhibited higher levels of clinical severity. CONCLUSIONS: In-hospital fatality rate might be significantly higher in the 2017-2018 season in China. A sufficient supply of oseltamivir and antiviral therapy within 48 h from onset could reduce fatality rates.


Assuntos
Antivirais/uso terapêutico , Epidemias , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/epidemiologia , Oseltamivir/uso terapêutico , Adolescente , Adulto , China/epidemiologia , Feminino , Hospitalização , Humanos , Influenza Humana/mortalidade , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...