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1.
Chem Asian J ; : e202400369, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38595045

RESUMO

Plastics are versatile materials, offering lightweight, durable, and affordable solutions across various industries. However, their non-degradable nature poses challenges by end of their life. This study presented an innovative carbonyl extraction method to utilize waste poly(bisphenol A carbonate) (PC) as reaction precursor to synthesis of activated furan as precursor for photoswitchable Stenhouse adducts. This innovative chemical strategy not only generated N,N'-functionalized barbiturates but also provided an eco-friendly and cost-effective alternative to traditional synthesis methods. The method presented hereby not only promotes sustainability by repurposing waste polycarbonate as carbonyl equivalent under green conditions but also yielded reusable bisphenol A (BPA). Furthermore, the derived activated furans exhibited their functionality by forming colored donor-acceptor Stenhouse adducts (DASAs) on aminated polymer surfaces. This work demonstrated a transition from a linear plastics economy toward a circular one, highlighting the potential of plastic waste as a resource for creating materials with improved properties.

2.
Mater Horiz ; 11(8): 1964-1974, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38348699

RESUMO

The rational design of heterostructured nanocrystals (HNCs) is of great significance for developing highly efficient hydrogen evolution reaction (HER) electrocatalysts. However, a significant challenge still lies in realizing the controllable synthesis of desired HNCs directly onto a support and exploring their structure-activity-dependent HER performance. Herein, we reported various controllable Pd7@Ptx core-shell HNCs with optimal hybrid structures via a photochemical deposition strategy. The growth patterns of a Pt shell can be finely controlled by adjusting the growth kinetics, resulting in a varying deposition rate. In particular, the as-prepared Pd7@Pt3 HNCs with a Pt shell in the Stranski-Krastanov mode showed the best performances over a wide pH range media, delivering low overpotentials of 33, 18 and 49 mV, resulting in a catalytic current density of 10 mA cm-2 at a low effective catalyst loading of 0.021 mg cm-2. The resulting Tafel slopes were 23.1, 52.6 and 42.7 mV dec-1 in 0.5 M H2SO4, 1.0 M phosphate-buffered saline (PBS) and 1.0 M KOH electrolyte, respectively. It was found that the increased fraction of unsaturated coordination of Pt islands in the resultant material is the key to the enhanced and robust HER activity, which has been confirmed through density functional theory (DFT) calculations. This strategy could be extended to the rational design and synthesis of other heterostructured catalysts for energy conversion and storage.

3.
ACS Sens ; 9(3): 1134-1148, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38363978

RESUMO

Exploring accurate, noninvasive, and inexpensive disease diagnostic sensors is a critical task in the fields of chemistry, biology, and medicine. The complexity of biological systems and the explosive growth of biomarker data have driven machine learning to become a powerful tool for mining and processing big data from disease diagnosis sensors. With the development of bioinformatics and artificial intelligence (AI), machine learning models formed by data mining have been able to guide more sensitive and accurate molecular computing. This review presents an overview of big data collection approaches and fundamental machine learning algorithms and discusses recent advances in machine learning and molecular computational disease diagnostic sensors. More specifically, we highlight existing modular workflows and key opportunities and challenges for machine learning to achieve disease diagnosis through big data mining.


Assuntos
Inteligência Artificial , Big Data , Aprendizado de Máquina , Mineração de Dados , Algoritmos
4.
Front Public Health ; 11: 1275551, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965512

RESUMO

Background: Syphilis has caused epidemics for hundreds of years, and the global syphilis situation remains serious. The reported incidence rate of syphilis in Zhejiang Province has ranked first in the province in terms of notifiable infectious diseases for many years and is the highest in China. This study attempts to use the scaling law theory to study the relationship between population size and different types of syphilis epidemics, while also exploring the main driving factors affecting the incidence of syphilis in different regions. Methods: Data on syphilis cases and affected populations at the county level were obtained from the China Disease Control and Prevention Information System. The scaling relationship between different stages of syphilis and population size was explained by scaling law. The trend of the incidence from 2016 to 2022 was tested by the joinpoint regression. The index of distance between indices of simulation and observation (DISO) was applied to evaluate the overall performance of joinpoint regression model. Furthermore, a multivariate time series model was employed to identify the main driving components that affected the occurrence of syphilis at the county level. The p value less than 0.05 or confidence interval (CI) does not include 0 represented statistical significance for all the tests. Results: From 2016 to 2022, a total of 204,719 cases of syphilis were reported in Zhejiang Province, including 2 deaths, all of which were congenital syphilis. Latent syphilis accounted for 79.47% of total syphilis cases. The annual percent change (APCs) of all types of syphilis, including primary syphilis, secondary syphilis, tertiary syphilis, congenital syphilis and latent syphilis, were - 21.70% (p < 0.001, 95% CI: -26.70 to -16.30), -16.80% (p < 0.001, 95% CI: -20.30 to -13.30), -8.70% (p < 0.001, 95% CI: -11.30 to -6.00), -39.00% (p = 0.001, 95% CI: -49.30 to -26.60) and - 7.10% (p = 0.008, 95% CI: -11.20 to -2.80), respectively. The combined scaling exponents of primary syphilis, secondary syphilis, tertiary syphilis, congenital syphilis and latent syphilis based on the random effects model were 0.95 (95% CI: 0.88 to 1.01), 1.14 (95% CI: 1.12 to 1.16), 0.43 (95% CI: 0.37 to 0.49), 0.0264 (95% CI: -0.0047 to 0.0575) and 0.88 (95% CI: 0.82 to 0.93), respectively. The overall average effect values of the endemic component, spatiotemporal component and autoregressive component for all counties were 0.24, 0.035 and 0.72, respectively. The values of the autoregressive component for most counties were greater than 0.7. The endemic component of the top 10 counties with the highest values was greater than 0.34. Two counties with value of the spatiotemporal component higher than 0.1 were Xihu landscape county and Shengsi county. From 2016 to 2022, the endemic and autoregressive components of each county showed obvious seasonal changes. Conclusion: The scaling exponent had both temporal trend characteristics and significant heterogeneity in the association between each type of syphilis and population size. Primary syphilis and latent syphilis exhibited a linear pattern, secondary syphilis presented a superlinear pattern, and tertiary syphilis exhibited a sublinear pattern. This suggested that further prevention of infection and transmission among high-risk populations and improvement of diagnostic accuracy in underdeveloped areas is needed. The autoregressive components and the endemic components were the main driving factors that affected the occurrence of syphilis. Targeted prevention and control strategies must be developed based on the main driving modes of the epidemic in each county.


Assuntos
Sífilis Congênita , Sífilis , Humanos , Sífilis/epidemiologia , China/epidemiologia
5.
Front Public Health ; 11: 1154944, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37427270

RESUMO

Background: Influenza infection causes a huge burden every year, affecting approximately 8% of adults and approximately 25% of children and resulting in approximately 400,000 respiratory deaths worldwide. However, based on the number of reported influenza cases, the actual prevalence of influenza may be greatly underestimated. The purpose of this study was to estimate the incidence rate of influenza and determine the true epidemiological characteristics of this virus. Methods: The number of influenza cases and the prevalence of ILIs among outpatients in Zhejiang Province were obtained from the China Disease Control and Prevention Information System. Specimens were sampled from some cases and sent to laboratories for influenza nucleic acid testing. Random forest was used to establish an influenza estimation model based on the influenza-positive rate and the percentage of ILIs among outpatients. Furthermore, the moving epidemic method (MEM) was applied to calculate the epidemic threshold for different intensity levels. Joinpoint regression analysis was used to identify the annual change in influenza incidence. The seasonal trends of influenza were detected by wavelet analysis. Results: From 2009 to 2021, a total of 990,016 influenza cases and 8 deaths were reported in Zhejiang Province. The numbers of estimated influenza cases from 2009 to 2018 were 743,449, 47,635, 89,026, 132,647, 69,218, 190,099, 204,606, 190,763, 267,168 and 364,809, respectively. The total number of estimated influenza cases is 12.11 times the number of reported cases. The APC of the estimated annual incidence rate was 23.33 (95% CI: 13.2 to 34.4) from 2011 to 2019, indicating a constant increasing trend. The intensity levels of the estimated incidence from the epidemic threshold to the very high-intensity threshold were 18.94 cases per 100,000, 24.14 cases per 100,000, 141.55 cases per 100,000, and 309.34 cases per 100,000, respectively. From the first week of 2009 to the 39th week of 2022, there were a total of 81 weeks of epidemics: the epidemic period reached a high intensity in 2 weeks, the epidemic period was at a moderate intensity in 75 weeks, and the epidemic period was at a low intensity in 2 weeks. The average power was significant on the 1-year scale, semiannual scale, and 115-week scale, and the average power of the first two cycles was significantly higher than that of the other cycles. In the period from the 20th week to the 35th week, the Pearson correlation coefficients between the time series of influenza onset and the positive rate of pathogens, including A(H3N2), A (H1N1)pdm2009, B(Victoria) and B(Yamagata), were - 0.089 (p = 0.021), 0.497 (p < 0.001), -0.062 (p = 0.109) and - 0.084 (p = 0.029), respectively. In the period from the 36th week of the first year to the 19th week of the next year, the Pearson correlation coefficients between the time series of influenza onset and the positive rate of pathogens, including A(H3N2), A (H1N1)pdm2009, B(Victoria) and B(Yamagata), were 0.516 (p < 0.001), 0.148 (p < 0.001), 0.292 (p < 0.001) and 0.271 (p < 0.001), respectively. Conclusion: The disease burden of influenza has been seriously underestimated in the past. An appropriate method for estimating the incidence rate of influenza may be to comprehensively consider the influenza-positive rate as well as the percentage of ILIs among outpatients. The intensity level of the estimated incidence from the epidemic threshold to the very high-intensity threshold was calculated, thus yielding a quantitative standard for judging the influenza prevalence level in the future. The incidence of influenza showed semi-annual peaks in Zhejiang Province, including a main peak from December to January of the next year followed by a peak in summer. Furthermore, the driving factors of the influenza peaks were preliminarily explored. While the peak in summer was mainly driven by pathogens of A(H3N2), the peak in winter was alternately driven by various pathogens. Our research suggests that the government urgently needs to address barriers to vaccination and actively promote vaccines through primary care providers.


Assuntos
Epidemias , Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Criança , Adulto , Humanos , Influenza Humana/epidemiologia , Incidência , Vírus da Influenza A Subtipo H3N2 , China/epidemiologia
6.
Nanomaterials (Basel) ; 12(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36080032

RESUMO

Roxarsone (ROX) as an organoarsenic feed additive has been widely used in livestock breeding and poultry industry, but ROX can degrade into highly toxic inorganic arsenic species in natural environments to threaten to the environment and human health. Therefore, there is a considerable interest in developing convenient, selective and sensitive methods for the detection of ROX in livestock breeding and poultry industry. In this work, a fluorescent molecularly imprinted polymer (MIPs) probe based on amino-modified Mn-ZnS quantum dots (QDs) has been developed by sol-gel polymerization for specific recognition of ROX. The synthesized MIPs-coated Mn-ZnS QDs (MIPs@Mn-ZnS QDs) have highly selective recognition sites to ROX because there are multi-interactions among the template ROX, functional monomer phenyltrimethoxysilane and the amino-functionalized QDs such as the π-π conjugating effect, hydrogen bonds. Under the optimal conditions, an obvious fluorescence quenching was observed when ROX was added to the solution, and the quenching mechanism could be explained as the photo-induced electron transfer. The MIPs@Mn-ZnS QDs sensor exhibited sensitive response to ROX in the linear range from 3.75 × 10-8 M to 6.25 × 10-7 M (R2 = 0.9985) and the limit of detection down to 4.34 nM. Moreover, the fluorescence probe has been applied to the quantitative detection of ROX in feed samples, and the recovery was in the range of 91.9% to 108.0%. The work demonstrated that the prepared MIPs@Mn-ZnS QDs probe has a good potential for rapid and sensitive determination of ROX in complicated samples.

7.
PLoS One ; 17(9): e0274421, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36126038

RESUMO

BACKGROUND: Zhejiang, ranked in the top three in HFMD (hand, foot, and mouth disease) incidence, is located in the Yangtze River Delta region of southeast China. Since 2016, the EV71 vaccine has been promoted in Zhejiang Province. This study aimed to investigate the trend and seasonal variation characteristics of HFMD from 2010 to 2021 and estimate the reduction in enterovirus 71 infection after vaccine use. METHODS: The data on HFMD cases in Zhejiang Province from January 2010 to December 2021 were obtained from this network system. Individual information on cases and deaths was imported, and surveillance information, including demographic characteristics and temporal distributions, was computed by the system. The Joinpoint regression model was used to describe continuous changes in the incidence trend. The BSTS (Bayesian structural time-series models) model was used to estimate the monthly number of cases from 2017 to 2021 based on the observed monthly incidence during 2010-2016 by accounting for seasonality and long-term trends. The seasonal variation characteristics of HFMD pathogens were detected by wavelet analysis. RESULTS: From 2010 to 2021, the annual incidence rate fluctuated between 98.81 cases per 100,000 in 2020 and 435.63 cases per 100,000 in 2018, and 1711 severe HFMD cases and 106 fatal cases were reported in Zhejiang Province, China. The annual percent change (APC) in EV71 cases was -30.72% (95% CI: -45.10 to -12.50) from 2016 to 2021. The wavelet transform of total incidence and number of cases of the three pathogens all showed significant periodicity on the 1-year scale. The average 2-year scale periodicity was significant for the total incidence, EV71 cases and Cox A16 cases, but the other enterovirus cases showed significant periodicity on the 30-month scale. The 6-month scale periodicity was significant for the total incidence, EV71 case and Cox A16 case but not for the other enteroviruses case. The relative error percentage of the performance of the BSTS model was 0.3%. The estimated number of cases from 2017 to 2021 after the EV-A71 vaccines were used was 9422, and the reduction in the number of cases infected with the EV71 virus was 73.43% compared to 70.80% when the impact of the COVID-19 epidemic in 2020 was excluded. CONCLUSIONS: Since 2010, the incidence of EV71 infections has shown an obvious downward trend. All types of viruses showed significant periodicity on the 1-year scale. The periodicity of the biennial peak is mainly related to EV71 and Cox A16 before 2017 and other enteroviruses since 2018. The half-year peak cycle of HFMD was mainly caused by EV71 and Cox A6 infection. The expected incidence will be 2.76 times(include the cases of 2020) and 2.43 times(exclude the cases of 2020) higher than the actual value assuming that the measures of vaccination are not taken. EV71 vaccines are very effective and should be administered in the age window between 5 months and 5 years.


Assuntos
COVID-19 , Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Vacinas , Antígenos Virais , Teorema de Bayes , China/epidemiologia , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/prevenção & controle , Humanos , Lactente
8.
STAR Protoc ; 3(3): 101459, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-35755128

RESUMO

Controlling the size and uniform dispersion of noble metal nanoclusters on the metal oxide based semiconductor are difficult due to the natural tendency for metal atoms to agglomerate. Here, we present the protocol for an "irradiation-dark" photochemical deposition to obtain uniform metal nanoclusters on semiconductor support, and the protocol for measuring the size and size distribution of metal nanoclusters. For complete details on the use and execution of this protocol, please refer to Wu et al. (2022).


Assuntos
Metais , Semicondutores , Óxidos
9.
iScience ; 25(1): 103572, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-34984328

RESUMO

Dispersing metal nanoclusters on the oxide supports is attracting close attention in heterogeneous catalysis, but great challenges still lie in controlling the size and dispersion of nanoclusters due to the inevitable agglomeration. Here, we propose a sequential photochemical deposition strategy named "first store, and then release" to uniformly fabricate the size-controlling noble metal nanoclusters on semiconductor oxides. Using the typical semiconductor TiO2, the photoexcited electrons can be first stored as reduced species (e.g. Ti3+) under irradiation and the Ti3+ species can optimize both the nucleation and growth processes in dark reaction, resulting in a uniform dispersing of various noble metals (Au, Pt, Ag etc.) with size diameters of ∼1 nm. The nanoclusters catalysts exhibited superior performance in catalytic oxidation of HCHO compared with that of nanoparticles. This work brings a new and useful strategy to construct size-controlling noble metals on the oxide supports for heterogeneous catalysis and the related fields.

10.
PLoS One ; 16(9): e0257587, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34534239

RESUMO

BACKGROUND: Zhejiang Province is one of the five provinces in China that had the highest incidence of novel coronavirus disease (COVID-19). Zhejiang, ranked fourth highest in COVID-19 incidence, is located in the Yangtze River Delta region of southeast China. This study was undertaken to identify the space-time characteristics of COVID-19 in Zhejiang. METHODS: Data on COVID-19 cases in Zhejiang Province from January to July 2020 were obtained from this network system. Individual information on cases and deaths was imported, and surveillance information, including demographic characteristics and geographic and temporal distributions, was computed by the system. The Knox test was used to identify possible space-time interactions to test whether cases that are close in distance were also close in time. Network analysis was performed to determine the relationship among the cases in a transmission community and to try to identify the key nodes. RESULTS: In total, 1475 COVID-19 cases and 1 fatal case were reported from January to July 2020 in Zhejiang Province, China. Most of the cases occurred before February 15th, which accounted for 90.10%. The imported cases increased and became the main risk in Zhejiang Province after February 2020. The risk areas showed strong heterogeneity according to the Knox test. The areas at short distances within 1 kilometer and at brief periods within 5 days presented relatively high risk. The numbers of subcommunities for the four clusters were 12, 9, 6 and 4. There was obvious heterogeneity in the modularity of subcommunities. The maximum values of the node centrality for the four clusters were 2.9474, 4.3706, 4.1080 and 2.7500. CONCLUSIONS: COVID-19 was brought under control over a short period in Zhejiang Province. Imported infections from outside of mainland China then became a new challenge. The effects of spatiotemporal interaction exhibited interval heterogeneity. The characteristics of transmission showed short range and short term risks. The importance to the cluster of each case was detected, and the key patients were identified. It is suggested that we should focus on key patients in complex conditions and in situations with limited control resources.


Assuntos
COVID-19 , COVID-19/epidemiologia , COVID-19/transmissão , China/epidemiologia , Humanos , Incidência , Análise Espaço-Temporal
11.
PLoS Negl Trop Dis ; 14(4): e0008186, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32255791

RESUMO

BACKGROUND: Zhejiang Province has the fifth-highest incidence of severe fever with thrombocytopenia syndrome (SFTS) in China. While the top four provinces are all located in northern and central China, only Zhejiang Province is located in the Yangtze River Delta region of southeast China. This study was undertaken to identify the epidemiological characteristics of SFTS in Zhejiang from 2011 to 2018. METHODS: The epidemic data from SFTS cases in Zhejiang Province from January 2011 to December 2018 were obtained from the China Information Network System of Disease Prevention and Control. Meteorological data were collected from the China Meteorological Data Sharing Service System. A multivariate time series model was used to analyze the heterogeneity of spatial-temporal transmission of the disease. Random forest analysis was performed to detect the importance of meteorological factors and the dose-response association of the incidence of SFTS with these factors. RESULTS: In total, 412 SFTS cases (49 fatal) were reported from January 2011 to December 2018 in Zhejiang Province, China. The number of SFTS cases and the number of affected counties increased year by year. The case fatality rate in Zhejiang Province was 11.89%, which was the highest in China. Elderly patients and farmers were the most affected. The total effect values of the autoregressive component, spatiotemporal component and endemic component of the model in all ranges were 0.4580, 0.0377 and 0.0137, respectively. There was obvious heterogeneity across counties for the mean values of the spatiotemporal component and the autoregressive component. The autoregressive component was obviously the main factor driving the occurrence of SFTS, followed by the spatiotemporal component. The importance scores of the monthly mean pressure, mean temperature, mean relative humidity, mean two-minute wind speed, duration of sunshine and precipitation were 10.64, 8.34, 8.16, 6.37, 5.35 and 2.81, respectively. The relationship between these factors and the incidence of SFTS is complicated and nonlinear. A suitable range of meteorological factors for this disease was also detected. CONCLUSIONS: The autoregressive and spatiotemporal components played an important role in driving the transmission of SFTS. Targeted preventive efforts should be made in different areas based on the main component contributing to the epidemic. For most areas, early measures several months ahead of the suitable season for the occurrence of SFTS should be implemented. The level of reporting and diagnosis of this disease should be further improved.


Assuntos
Infecções por Bunyaviridae/epidemiologia , Febre/epidemiologia , Sistemas de Informação Geográfica , Conceitos Meteorológicos , Trombocitopenia/epidemiologia , Idoso , Infecções por Bunyaviridae/diagnóstico , China/epidemiologia , Feminino , Febre/diagnóstico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Phlebovirus , Análise Espaço-Temporal , Trombocitopenia/diagnóstico
12.
Talanta ; 210: 120632, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31987190

RESUMO

An efficient and selective glycoproteins enrichment platform is essential to glycoprotein biomarkers in early clinic diagnostics. In this work, the poly (ethylene glycol) methyl ether methacrylate (PEGMA) and 4-vinylphenylboronic acid (VPBA) copolymer brushes grafted magnetic carbon nanotubes composite MCNTs@p (PEGMA-co-VPBA) was prepared by surface-initiated atom transfer polymerization and applied for the selective enrichment of glycoproteins from the complex biological samples. The as-prepared MCNTs@p (PEGMA-co-VPBA) nanocomposite was characterized by Fourier transform-infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometry (VSM). The MCNTs@p (PEGMA-co-VPBA) can recognize and bind specifically for glycoproteins via strong boronate affinity and excellent hydrophilicity and shows a really low non-specificity adsorption capability for non-glycoproteins. The adsorption capacity of MCNTs@p (PEGMA-co-VPBA) towards glycoproteins transferrin (Trf), horseradish peroxidase (HRP), and non-glycoproteins cytochrome c (Cyt C), lysozyme (Lyz) is 253.3 mg g-1, 51.1 mg g-1, 13.9 mg g-1 and 14.5 mg g-1, respectively. Furthermore, MCNTs@p (PEGMA-co-VPBA) can be applied to extract glycoproteins directly from egg white samples. These results demonstrated that MCNTs@p (PEGMA-co-VPBA) could be a potential affinity adsorbent in glycoprotein enrichment.


Assuntos
Ácidos Borônicos/química , Glicoproteínas/química , Metacrilatos/química , Nanotubos de Carbono/química , Polietilenoglicóis/química , Adsorção , Animais , Galinhas , Clara de Ovo/química , Interações Hidrofóbicas e Hidrofílicas , Fenômenos Magnéticos , Tamanho da Partícula , Propriedades de Superfície
13.
Se Pu ; 38(1): 2-13, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34213145

RESUMO

With the increasing complexity of the sample properties in analytical chemistry and the lower concentrations of the detected substances, it is imperative to develop accurate and efficient sample pretreatment processes before chromatography and mass spectrometry analyses. Magnetic solid-phase extraction (MSPE) can be regarded as an efficient sample pretreatment method due to the simple synthesis, convenient operation, and high extraction efficiency. In recent years, Fe3O4 magnetic nanomaterials have been widely used in separation and analysis due to their advantages such as high separation speed, good dispersion, and biocompatibility. Functionalized Fe3O4 magnetic nanomaterials are expected to show greatly improved physical and chemical stability, with superior adsorption and separation ability. In this paper, the preparation of magnetic nanomaterials functionalized with carbon-based nanomaterials, molecularly imprinted polymers, ionic liquids, boronate affinity ligands, metal organic frameworks, covalent organic frames, quantum dots, and metal oxides and their applications to sample pretreatment in the fields of biological, environmental, and food safety are reviewed. In addition, future research on sample pretreatment processes is prospected.

14.
Anal Bioanal Chem ; 412(1): 203-222, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31802178

RESUMO

This study examines an improved and simplified method for solid-phase extraction (SPE), which offers rapid and accurate determination and identification of 44 pharmaceutically active compounds using ultra-performance liquid chromatography (UPLC) and tandem mass spectrometry (MS/MS). The common active compounds include four macrolides, seventeen sulfonamides, four quinolones, chloramphenicol, eight ß-lactams, four tetracyclines, lincomycin, amantadine, 4-acetamidophenol, phenylbutazone, trimethoprim, clenbuterol, and hydrocortisone in water samples. We optimized crucial parameters of MS/MS, UPLC, and SPE and studied the matrix effect related to the modified analytical process from water samples. The matrix-matched calibration curves were accomplished at seven concentration levels and a satisfactory linear relationship (r2 > 0.994) was observed within the range of 0.1-500 ng/mL. Results show varying limits of detection (0.0111-0.966 ng/L for different analytes based on signal-to-noise (S/N) = 3) and limits of quantitation (0.0382-3.26 ng/L). Recoveries of the spiked samples ranged from 75.7 to 108% with relative standard deviation lower than 9.6%. The proposed method was successfully applied to the analysis of real samples.


Assuntos
Cromatografia Líquida/métodos , Preparações Farmacêuticas/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise , Limite de Detecção , Preparações Farmacêuticas/normas , Padrões de Referência , Reprodutibilidade dos Testes
15.
Artigo em Inglês | MEDLINE | ID: mdl-31533311

RESUMO

OBJECTIVE: The aim of this study was to analyze the trends and epidemiological characteristics of scarlet fever in Zhejiang Province in 2004-2018, intending to provide a basis for targeted prevention and control of this disease. METHOD: We collated the epidemiological data for cases of scarlet fever from the China Information System for Disease Control and Prevention (CISDCP) in Zhejiang province between 1 January 2004 and 31 December 2018. Descriptive statistical analysis was used to analyze epidemiological characteristics of scarlet fever, whereas the Getis-Ord Gi* statistic was used to determine the hotspot incidence of scarlet fever. RESULTS: In 2004-2018, a total of 22,194 cases of scarlet fever were reported in Zhejiang Province, with no death reports. The annual average of scarlet fever incidence was 2.82/100,000 (range,1.12 to 6.34/100,000). The male incidence was higher than that among female (χ2 = 999.834, p < 0.05), and a majority of the cases (86.42%) occurred in children aged 3-9 years. Each year, the incidence of scarlet fever in Zhejiang Province appeared two seasonal peaks: the first peak occurred from March to June (the constituent ratio was 49.06%), the second peak was lower than the first one during November and the following January (the constituent ratio was 28.67%). The two peaks were almost in accordance with the school spring semester and autumn-winter semester, respectively. The incidence in the northern regions of the province was generally higher than that in the southern regions. High-value clusters were detected in the central and northern regions, while low-value clusters occurred in the southern regions via the Getis-Ord Gi* statistical analysis. CONCLUSIONS: The prevalence of scarlet fever in Zhejiang Province showed a marked seasonality variation and mainly clustered in the central and northern regions in 2004-2018. Children under 15 years of age were most susceptible to scarlet fever. Kindergartens and primary schools should be the focus of prevention and control, and targeted strategies and measures should be taken to reduce the incidence.


Assuntos
Escarlatina/epidemiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Clima , Feminino , História do Século XXI , Humanos , Incidência , Masculino , Prevalência , Instituições Acadêmicas , Estações do Ano
16.
PLoS One ; 14(8): e0220391, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31393899

RESUMO

BACKGROUND: The number of dengue fever (DF) cases and the number of dengue outbreaks have increased in recent years in Zhejiang Province, China. An unexpected dengue outbreak was reported in Hangzhou in 2017 and caused more than one thousand dengue cases. This study was undertaken to evaluate the effectiveness of the actual control measures, estimate the proportion of inapparent infections during this outbreak and simulate epidemic development based on different levels of control measures taking inapparent infections into consideration. METHODS: The epidemic data of dengue cases in Hangzhou, Zhejiang Province, in 2017 and the number of the people exposed to the outbreaks were obtained from the China Information Network System of Disease Prevention and Control. The epidemic without intervention measures was used to estimate the unknown parameters. A susceptible-exposed-infectious/inapparent-recovered (SEIAR) model was used to estimate the effectiveness of the control interventions. The inapparent infections were also evaluated at the same time. RESULTS: In total, 1137 indigenous dengue cases were reported in Hangzhou in 2017. The number of indigenous dengue cases was estimated by the SEIAR model. This number was predicted to reach 6090 by the end of November 2, 2017, if no control measures were implemented. The total number of reported cases was reduced by 81.33% in contrast to the estimated incidence without intervention. The number of average daily inapparent cases was 10.18 times higher than the number of symptomatic cases. The earlier and more rigorously the vector control interventions were implemented, the more effective they were. The results showed that implementing vector control continuously for more than twenty days was more effective than every few days of implementation. Case isolation is not sufficient enough for epidemic control and only reduced the incidence by 38.10% in contrast to the estimated incidence without intervention, even if case isolation began seven days after the onset of the first case. CONCLUSIONS: The practical control interventions in the outbreaks that occurred in Hangzhou City were highly effective. The proportion of inapparent infections was large, and it played an important role in transmitting the disease during this epidemic. Early, continuous and high efficacy vector control interventions are necessary to limit the development of a dengue epidemic. Timely diagnosis and case reporting are important in the intervention at an early stage of the epidemic.


Assuntos
Infecções Assintomáticas/epidemiologia , Dengue , Surtos de Doenças , Modelos Biológicos , China/epidemiologia , Dengue/epidemiologia , Dengue/transmissão , Feminino , Humanos , Incidência , Masculino
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 214: 393-398, 2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-30802796

RESUMO

A highly selective and sensitive colorimetric sensor based on aggregation-induced color change of 4-mercaptophenylboronic modified gold nanoparticles was designed for the determination of fluoride anion. The 4-mercaptophenylboronic modified gold nanoparticles were synthesized by a simple one-pot reaction. The aggregation process occurred when interaction between fluoride anion and 4-mercaptophenylboronic on the surface of gold nanoparticles took place; as a result, fluoroborate anions were formed coupled with changes in the electronic properties of the AuNPs. The change can be measured by UV-Vis absorption spectra. The sensor shows good selectivity and sensitivity for fluoride anion. The linear range is 10.0-30.0 µM for fluoride and the detection limit of fluoride is 3.45 × 10-7 M according to IUPAC criteria (3σ rule). Furthermore, the sensor has been used for the detection of fluoride anion in tap water, ground water and human serum samples, the recovery can achieve 94.0%-103.3%, 94.7%-101.0% and 89.8-100.9%, respectively. The excellent performance of colorimetric sensor in the detection of the fluoride anion demonstrated the potential application in the detecting fluoride anion present in the complex environmental and biological samples.

18.
Nanoscale ; 11(17): 8160-8169, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30723852

RESUMO

Exploration of effective metal/support combinations and new fabrication approaches is attractive in the catalytic oxidation of HCHO. In this study, we proposed graphitic carbon nitride (g-C3N4) as a non-metal oxide based support to co-load Pt and MnOx through room-temperature photodeposition and in turn applied for HCHO oxidation. Here, Pt was the active component, while MnOx was the cocatalyst to compensate the shortage of active oxygen on g-C3N4. g-C3N4 was found as a promising support for the high dispersion of Pt and MnOx. Well dispersed Pt nanoparticles with an average diameter of 1.8 nm were obtained, which were highly favorable for the loading of MnOx as MnOx-Pt/g-C3N4. Catalytic performance results indicated that the limited HCHO conversion over g-C3N4 and Pt/g-C3N4 was significantly promoted with the introduction of MnOx, with an optimum MnOx amount of 3.0 wt%. The developed catalysts remained highly stable for 30 h. The enhanced catalytic activity of MnOx-Pt/g-C3N4 was due to the increased number of active oxygen species with the introduction of MnOx and the efficient transfer of electrons from g-C3N4 to Pt. Compared to the traditional impregnation, photodeposition process avoids the application of H2 and high temperatures, scoring in favor of its green and safe nature. This study can concomitantly provide a new way for the design and fabrication of a non-metal oxide based support for the efficient HCHO catalytic oxidation and the application of the photocatalytic process in catalyst fabrication.

19.
Artigo em Inglês | MEDLINE | ID: mdl-30634443

RESUMO

This study aims to learn the characteristics of morbidity and mortality of notifiable diseases reported in children aged 0⁻14 years in Zhejiang Province in 2008⁻2017. We collated data from the China Information System for Disease Control and Prevention in Zhejiang province between 1 January 2008 and 31 December 2017 of children aged 0⁻14 years. From 2008 to 2017, a total of 32 types and 1,994,740 cases of notifiable diseases were reported in children aged 0⁻14 years, including 266 deaths in Zhejiang Province. The annual average morbidity was 2502.87/100,000, and the annual average mortality was 0.33/100,000. Male morbidity was 2886.98/100,000, and female morbidity was 2072.16/100,000, with the male morbidity rate higher than the female morbidity rate (χ² = 54,033.12, p < 0.01). No Class A infectious diseases were reported. The morbidity of Class B infectious diseases showed a downward trend, but that of Class C infectious diseases showed an upward trend. There were 72,041 cases in 22 kinds of Class B infectious disease and 138 death cases, with a morbidity rate of 90.39/100,000, and a mortality rate of 0.17/100,000. There were 1,922,699 cases in 10 kinds of Class C infectious disease and 128 death cases, with a morbidity rate of 2412.47/100,000, and a mortality rate of 0.16/100,000. The main high-prevalence diseases included hand-foot-and-mouth disease (1430.38/100,000), other infectious diarrheal diseases (721.40/100,000), mumps (168.83/100,000), and influenza (47.40/100,000). We should focus on the prevention and control of hand-foot and mouth disease, other infectious diarrheal diseases, mumps and influenza in children aged 0⁻14 years in Zhejiang Province. It is recommended to strengthen epidemic surveillance and undertake early prevention and control measures in order to reduce the younger children incidence rate of infectious diseases. Immunization planning vaccines can help achieve a significant preventive decline of infectious diseases.


Assuntos
Doenças Transmissíveis/epidemiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Doenças Transmissíveis/classificação , Doenças Transmissíveis/história , Doenças Transmissíveis/mortalidade , Monitoramento Epidemiológico , Feminino , História do Século XXI , Humanos , Lactente , Recém-Nascido , Masculino , Morbidade/tendências , Prevalência
20.
Bioconjug Chem ; 29(11): 3595-3605, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30285419

RESUMO

The retro Michael-type addition and thiol exchange of thioether succinimide click linkages in response to thiol-containing environments offers a novel strategy for the design of glutathione-sensitive degradable hydrogels for controlled drug delivery. Here we characterize the kinetics and extent of the retro Michael-type addition and thiol exchange with changes in both the p Ka of the thiols and the identity of N-substituents of maleimides. A series of N-substituted thioether succinimides were prepared through typical Michael-type addition. Model studies (1H NMR, HPLC) of 4-mercaptophenylacetic acid (MPA, p Ka 6.6) conjugated to N-ethyl maleimide (NEM), N-phenyl maleimide (NPM), or N-aminoethyl maleimide (NAEM) and then incubated with glutathione showed half-lives of conversion from 3.1 to 18 h, with extents of conversion from approximately 12% to 90%. The variations in the rates of exchange and hydrolytic ring opening appear to be mediated by resonance effects, electron-withdrawing capacity of the N-substituted moiety, as well as the potential for intramolecular catalytic hydrogen bonding of amine substituents with water (particularly in the case of ring opening). Further model studies of 4-mercaptohydrocinnamic acid (MPP, p Ka 7.0) and N-acetyl-l-cysteine (NAC, p Ka 9.5) conjugated to selected N-substituted maleimides and then incubated with glutathione showed half-lives of conversion from 3.6 to 258 h, with extents of conversion from approximately 1% to 90%. A higher p Ka of the thiol decreased the rate of the exchange reaction and limited the impact of other electronic effects of N-substituents on the extents of conversion. Additional factors affecting the conversion kinetics were studied on NEM conjugates. The kinetics of the retro Michael-type addition and exchange reaction were not hindered by thiol traps of lower p Ka, but were retarded in conditions of lower pH. These studies shed light into details of thiol and maleimide design that could be used to tune the rates of degradation of drug and polymer conjugates for a variety of applications.


Assuntos
Glutationa/química , Maleimidas/química , Compostos de Sulfidrila/química , Cromatografia Líquida de Alta Pressão , Meia-Vida , Hidrólise , Cinética , Espectroscopia de Prótons por Ressonância Magnética
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