RESUMO
Excessive intake of estrogen poses significant health risks to the human body; hence, there is a necessity to develop rapid detection methods to monitor its levels of addition. Gold nanoparticles (AuNPs), commonly utilized as colorimetric signal labels, find extensive application in lateral flow immunoassay (LFIA). However, the detection sensitivity of traditional AuNPs-LFIA is typically constrained by low molar extinction coefficients and reliance on a single signal. Herein, in this work, unique spark-type AuCuPt nanoflowers modified with tannic acid (AuCuPt@TA) were precisely designed by reasonable layer-by-layer element composition and green modification. The obtained AuCuPt displays robust broadband absorption spanning the visible to near-infrared spectrum, showcasing a notable molar extinction coefficient of 2.38 × 1012 M-1 cm-1 and a photothermal conversion efficiency of 48.5%. Based on this, selecting estriol (E3) as a model analyte, colorimetric/photothermal dual-signal LFIA (CLFIA and PLFIA) was developed. Limits of detection (LOD) of the CLFIA and PLFIA were achieved at 0.033 ng mL-1 and 0.021 ng mL-1, respectively, which represent a 9.3- and 14.6-fold improvement compared to the visual LOD of AuNPs-LFIA. Moreover, the application feasibility of the immunoassay was further evaluated in the milk and pork with satisfactory recoveries ranging from 86.21% to 117.91%. Thus, this work has enhanced the performance of LFIA for E3 detection and exhibited enormous potential for other sensing platform construction.
Assuntos
Ligas , Estriol , Ouro , Nanopartículas Metálicas , Imunoensaio/métodos , Nanopartículas Metálicas/química , Ouro/química , Estriol/análise , Ligas/química , Animais , Colorimetria , Limite de Detecção , Taninos/química , Taninos/análiseRESUMO
OBJECTIVE: To evaluate the performance of China's infectious disease automated alert and response system in the detection of outbreaks of hand, foot and mouth (HFM) disease. METHODS: We estimated size, duration and delay in reporting HFM disease outbreaks from cases notified between 1 May 2008 and 30 April 2010 and between 1 May 2010 and 30 April 2012, before and after automatic alert and response included HFM disease. Sensitivity, specificity and timeliness of detection of aberrations in the incidence of HFM disease outbreaks were estimated by comparing automated detections to observations of public health staff. FINDINGS: The alert and response system recorded 106,005 aberrations in the incidence of HFM disease between 1 May 2010 and 30 April 2012 - a mean of 5.6 aberrations per 100 days in each county that reported HFM disease. The response system had a sensitivity of 92.7% and a specificity of 95.0%. The mean delay between the reporting of the first case of an outbreak and detection of that outbreak by the response system was 2.1 days. Between the first and second study periods, the mean size of an HFM disease outbreak decreased from 19.4 to 15.8 cases and the mean interval between the onset and initial reporting of such an outbreak to the public health emergency reporting system decreased from 10.0 to 9.1 days. CONCLUSION: The automated alert and response system shows good sensitivity in the detection of HFM disease outbreaks and appears to be relatively rapid. Continued use of this system should allow more effective prevention and limitation of such outbreaks in China.
Assuntos
Notificação de Doenças/métodos , Surtos de Doenças , Doença de Mão, Pé e Boca/epidemiologia , China/epidemiologia , Feminino , Humanos , Masculino , Vigilância da População/métodos , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: Since HFMD was designated as a class C communicable disease in May 2008, 18 months surveillance data have been accumulated to December 2009. This article was to describe the distribution of HFMD for age, sex, area, and time between 2008 and 2009, to reveal the characteristics of the epidemic. METHODS: We analyzed weekly reported cases of HFMD from May 2008 to December 2009, and presented data on the distribution of age, sex, area and time. A discrete Poisson model was used to detect spatial-temporal clusters of HFMD. RESULTS: More than 1 065 000 cases of HFMD were reported in Mainland China from May 2008 to December 2009 (total incidence: 12.47 per 10 000). Male incidence was higher than female for all ages and 91.9% of patients were <5 years old. The incidence was highest in Beijing, Shanghai, Zhejiang and Hainan. The highest peak of HFMD cases was in April and the number of cases remained high from April to August. The spatial-temporal distribution detected four clusters. CONCLUSION: Children <5 years old were susceptible to HFMD and we should be aware of their vulnerability. The incidence was higher in urban than rural areas, and an annual pandemic usually starts in April.
Assuntos
Doença de Mão, Pé e Boca/epidemiologia , Envelhecimento , Pré-Escolar , China/epidemiologia , Análise por Conglomerados , Feminino , Humanos , Incidência , Lactente , Masculino , Caracteres Sexuais , Fatores de TempoRESUMO
The development of biopolymer-based films for food packaging is increasing owing to their environmental appeal, renewability, and biodegradability. In this study, transparent and biodegradable konjac glucomannan (KGM)/chitosan (CS)/TEMPO-oxidized chitin nanocrystal (TEMPO-ChNCs) bionanocomposite films were prepared. The TEMPO-ChNCs were prepared from chitin using the 2,2,6,6-tetramethylpiperidine-1-oxylradical (TEMPO) oxidation method and were used as a reinforcement nanofiller for the bionanocomposite films. The effect of TEMPO-ChNCs content on both rheological properties of film-forming solutions (FFS) and structural and physical properties of the resultant films was investigated. The rheological results of the FFS revealed that the TEMPO-ChNCs interacted with KGM and CS through electrostatic interaction and the hydrogen bonds in the bionanocomposite matrix, which was in agreement with the Fourier transform infrared spectroscopy and X-ray diffraction results. The microstructure of the films showed that 3% (w/w) TEMPO-ChNCs were homogeneously dispersed within the KGM/CS matrix, reducing the free volume of the biocomposite matrix and improving the final film mechanical and barrier properties (Pâ¯<â¯0.05). Furthermore, these bionanocomposite films exhibited good thermal stability. The incorporation of TEMPO-ChNCs in the KGM/CS matrix produced flexible and transparent bionanocomposite films. Thus, this bionanocomposite films has potential use in food packaging applications.
Assuntos
Biopolímeros/química , Quitina/química , Quitosana/química , Óxidos N-Cíclicos/química , Mananas/química , Membranas Artificiais , Nanocompostos/química , Nanopartículas/química , Fenômenos Mecânicos , Análise Espectral , TermogravimetriaRESUMO
OBJECTIVE: The purpose of this study was to analyze the distribution, temporal and spatial clustering characteristics and changes of severe hand, foot, and mouth disease (HFMD) in order to provide evidence-based decision making strategy for control and prevention of severe HFMD cases. METHODS: Severe HFMD cares were extracted from the National Diseases Reporting System of Chinese Center for Disease Control and Prevention (CDC) between 2008 and 2013. Definition and clinical diagnostic criteria of severe HFMD cases were set up by China CDC in the Hand, Foot, and Mouth Disease Control and Prevention Guideline, version 2010. Spatial scan unit was under the district/county of 2 900 in mainland China with temporal scan unit as month and time span as from May 2008 to August 2013. Kulldorff scan statistics was applied and analyses were conducted by SaTScan(TM) 9.1. Mapping and visualizing the results were carried out with ArcGIS 10.0. RESULTS: Data related to the monitoring program on severe HFMD from 2008 to 2013 demonstrated that above 96% of the severe HFMD cases occurred under 5 years old, mostly males, with the ratio of males to females as 1.73-1.80 and over 84% of the children were 'scattered'. Results from SaTScan illustrated that the temporal and spatial clustering existed among severe HFMD cases. The temporal dimension of severe HFMD was from May to July each year. Spatial dimension was located in south-east coastal area and middle-east area. With respect to the changes of temporal and spatial clustering phenomena, Class 1 clustering area was located in south-east coastal region in 2008 and in middle-east region in 2009 and was shifting to the west from middle-east region in 2010. It moved to the north-east from middle-east region in 2011 and to the north-west and south-west from middle-east region in 2012. Class 1 clustering area covered districts/countries from 18 provinces in 2012. The same pattern of Class 1 clustering area was observed as in the previous year-2013, but with less districts/countries from the 13 provinces. CONCLUSION: Temporal and spatial clustering areas of severe HFMD were presented in this report, and the yearly changing pattern of the clustering areas was noted. Findings from this study provided evidence-based data to the decision-making authorities so as to prevent deaths from severe HFMD cases under reasonable prevention and control strategies.
Assuntos
Doença de Mão, Pé e Boca/epidemiologia , Pré-Escolar , China/epidemiologia , Análise por Conglomerados , Feminino , Humanos , Lactente , Recém-Nascido , MasculinoRESUMO
OBJECTIVE: The purpose of this study was to explore the spatial clustering, specific clustering areas, as well as changing trend of clustering areas of hand-foot-mouth disease (HFMD). METHODS: Exploratory spatial data analysis (ESDA) was used to conduct spatial statistical analyses for the HFMD using 2008 - 2011 data at both provincial and county/district levels. RESULTS: The Global Moran's I coefficients appeared to be 0.3336, 0.6074, 0.3372, 0.4620 and 0.4367 for 2008 - 2011 and for the combined 4 years, respectively. The corresponding P-values were 0.002, 0.001, 0.004, 0.001 and 0.001 respectively, when using the Monte Carlo tests with all the P-values less than 0.05. Moran's I coefficients ranged between 0.3 and 0.7, showing the appearance of moderate or higher clustering nature. Based on the results from nationwide analyses on clustering areas at the county/district levels between 2008 and 2011 (Moran's I = 0.5198, P = 0.001), it appeared a moderate clustering nature. When local autocorrelation analysis was applied at the provincial level, 3 hot spot areas in Beijing, Tianjin and Shanghai cities in 2008; 7 hot spot areas in Beijing, Tianjin, Hebei, Shanxi, Shanghai, Jiangsu and Shandong in 2009; four hot spot areas: Beijing, Tianjin, Guangdong and Guangxi; five hot spot areas: Fujian, Jiangxi, Hunan, Guangdong and Guangxi in 2011, were discovered. 390 hot-spot counties/districts were found through local autocorrelation analyses using the three-year data of 2008 to 2010. CONCLUSION: Spatial clustering nature of HFMD incidence between 2008 and 2011 in China appeared to be moderate or high, with the clustered areas a north to south shifting trend. However, further investigation was in need to address this changing trend.