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1.
Emerg Microbes Infect ; 11(1): 2207-2210, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35993324

RESUMO

In 2021, twenty children exhibiting influenza-like illnesses were reported from a kindergarten in Shandong Province, China. Eleven genomes of Coxsackievirus A4 (CV-A4) were obtained from the pediatric cases, sharing <93% genome sequence identities with known CV-A4 strains. Further analyses suggested potential genetic recombination in the P3 region of the novel strains.


Assuntos
Surtos de Doenças , Doença de Mão, Pé e Boca , Criança , China/epidemiologia , Genótipo , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Filogenia
2.
Lancet Microbe ; 3(7): e512-e520, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35617977

RESUMO

BACKGROUND: Chlamydia psittaci can infect a wide range of avian species, occasionally causing psittacosis (also known as parrot fever) in humans. Most human psittacosis cases are associated with close contact with pet birds or poultry. In December, 2020, an outbreak of severe community-acquired pneumonia of unknown aetiology was reported in a hospital in Shandong province, China, and some of the patients' close contacts had respiratory symptoms. Our aims were to determine the causative agent of this epidemic and whether there had been human-to-human transmission. METHODS: For this epidemiological and aetiological investigation study, we enrolled patients who had community-acquired pneumonia confirmed by chest CT at two local hospitals in Shandong Province in China. We collected sputum, bronchoalveolar lavage fluid, and nasopharyngeal swab samples from participants and detected pathogens by surveying for 22 target respiratory microbes using a commercial assay, followed by metagenomic next-generation sequencing, specific nested PCR, and qPCR tests. We excluded individuals who were C psittaci-negative on both tests. We recruited close contacts of the C psittaci-positive patients, and tested nasopharyngeal swabs from the close contacts and samples from ducks from the processing plant where these patients worked. We then integrated the epidemiological, clinical, and laboratory data to reveal the potential chain of transmission of C psittaci that characterised this outbreak. FINDINGS: Between Dec 4 and 29, 2020, we used metagenomic next-generation sequencing and different PCR-based approaches to test 12 inpatients with community-acquired pneumonia, of whom six (50%) were workers at a duck-meat processing plant and two (17%) were unemployed people, who were positive for C psittaci and enrolled in this study. We contacted 61 close contacts of the six patients who worked at the duck-meat processing plant, of whom 61 (100%) were enrolled and tested, and we determined that the community-acquired pneumonia outbreak was caused by C psittaci. Within the outbreak cluster, 17 (77%) of 22 participants had confirmed C psittaci infections and five (23%) of 22 participants were asymptomatic C psittaci carriers. The outbreak had begun with avian-to-human transmission, and was followed by secondary and tertiary human-to-human transmission, which included transmission by several asymptomatic carriers and by health-care workers. In addition, some of the participants with confirmed C psittaci infection had no identified source of infection, which suggested cryptic bacterial transmission. INTERPRETATION: Our study data might represent the first documented report of human-to-human transmission of C psittaci in China. Therefore, C psittaci has the potential to evolve human-to-human transmission via various routes, should be considered an elevated biosecurity and emergent risk, and be included as part of the routine diagnosis globally, especially for high-risk populations. FUNDING: Academic Promotion Programme of Shandong First Medical University, National Science and Technology Major Project, ARC Australian Laureate Fellowship.


Assuntos
Chlamydophila psittaci , Infecções Comunitárias Adquiridas , Pneumonia , Psitacose , Animais , Austrália , Aves , China/epidemiologia , Chlamydophila psittaci/genética , Infecções Comunitárias Adquiridas/diagnóstico , Humanos , Pneumonia/diagnóstico , Psitacose/diagnóstico
4.
Int J Clin Exp Med ; 8(8): 12297-306, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26550139

RESUMO

OBJECTIVE: Aim to investigate the proportion of CD14(+)CD16(+) monocytes and understand the pathogenesis of this monocyte subset in acute leukemia. METHODS: Flow cytometry was utilized to study the phenotype expression of CD14(+)CD16(+) monocytes and CD3(+) T lymphocytes in peripheral blood derived from patients with acute leukemia. All the data were analyzed by SPSS 13.0 software. RESULTS: The proportion of CD14(+)CD16(+) monocytes including both intermediate and non-classical monocytes, increased significantly in patients with acute leukemia and changed negatively or positively according to the disease process. Meanwhile, the proportion of CD14(+)CD16(+) monocytes was inversely correlated with absolute number of CD4(+) T lymphocytes, ratio of CD4(+)/CD8(+) T cells, and positively correlated with the proportion of neutrophil granulocytes. CONCLUSIONS: The proportion of CD14(+)CD16(+) monocytes (especially the intermediate subpopulation) is related to the progression of acute leukemia, and the expansion of this monocyte subset could indicate the severity of the disease.

6.
Vet Res ; 46: 44, 2015 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-25928577

RESUMO

Cases of H9N2 avian influenza virus (AIV) in poultry are increasing throughout many Eurasian countries, and co-infections with other pathogens have resulted in high morbidity and mortality in poultry. Few studies have investigated the genetic factors of virus airborne transmission which determine the scope of this epidemic. In this study, we used specific-pathogen-free chickens housed in isolators to investigate the airborne transmissibility of five recombinant H9N2 AIV rescued by reverse genetic technology. The results show that airborne transmission of A/Chicken/Shandong/01/2008 (SD01) virus was related to the neuraminidase (NA) gene, and four amino acid mutations (D368E, S370L, E313K and G381D) within the head region of the SD01 NA, reduced virus replication in the respiratory tract of chickens, reduced virus NA activity, and resulted in a loss of airborne transmission ability in chickens. Similarly, reverse mutations of these four amino acids in the NA protein of r01/NASS virus, conferred an airborne transmission ability to the recombinant virus. We conclude that these four NA residues may be significant genetic markers for evaluating potential disease outbreak of H9N2 AIV, and propose that immediate attention should be paid to the airborne transmission of this virus.


Assuntos
Substituição de Aminoácidos , Galinhas , Vírus da Influenza A Subtipo H9N2/fisiologia , Influenza Aviária/transmissão , Neuraminidase/genética , Doenças das Aves Domésticas/transmissão , Proteínas Virais/genética , Animais , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/virologia , Neuraminidase/metabolismo , Doenças das Aves Domésticas/virologia , Proteínas Virais/metabolismo
7.
J Environ Manage ; 132: 178-87, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24316751

RESUMO

There is an urgent requirement to examine the quality of harvested rainwater for potable and non-potable purposes, based on the type of roofing material. In this study, we examined the effect on the quality of harvested rainwater of conventional roofing materials (concrete, asphalt and ceramic tile roofs) compared with alternative roofing materials (green roof). The results showed that the ceramic tile roof was the most suitable for rainwater-harvesting applications because of the lower concentrations of leachable pollutants. However, in this study, the green roof was not suitable for rainwater harvesting applications. In addition, seasonal trends in water quality parameters showed that pollutants in roof runoff in summer and autumn were lower than those in winter and spring. This study revealed that the quality of harvested rainwater was significantly affected by the roofing material; therefore, local government and urban planners should develop stricter testing programs and produce more weathering resistant roofing materials to allow the harvesting of rainwater for domestic and public uses.


Assuntos
Materiais de Construção/análise , Chuva/química , Qualidade da Água , Abastecimento de Água/análise , China , Monitoramento Ambiental , Análise Multivariada , Estações do Ano
8.
Environ Monit Assess ; 185(12): 9763-75, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23793645

RESUMO

This study investigates the quality of stormwater runoff from a driveway in the southwest mountainous urban area of Chongqing, China, from 2010 to 2011. The results showed that the mean concentrations of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) were 4.1, 2.4, and 2.2 times the grade V levels of the national surface water standard of China. The pollutant concentration peak preceded or synchronized with the rainfall intensity peak and occurred 10 min after the runoff started. The significant high pollutant concentration in the initial stage of the rainfall suggested that first flush control is necessary, especially for the most polluted constitutes, such as total suspended solids, COD, and TN. Three potential pollution sources were identified: the atmospheric dry and wet deposition (TN, NO3(-)-N, NH4(+)-N, and DCu), the road sediment and materials (total suspended solids, COD, and TP), and the vehicle emissions (DPb and DZn). Therefore, this study indicates that reductions in road sediments and material pollution and dry and wet deposition should be the priority factors for pollution control of road stormwater runoff in mountainous urban areas.


Assuntos
Chuva , Movimentos da Água , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Nitrogênio/análise , Fósforo/análise , Poluição Química da Água/análise
9.
Virol J ; 10: 204, 2013 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-23800032

RESUMO

BACKGROUND: The novel swine-origin influenza A (H1N1) virus (S-O 2009 IV) can cause respiratory infectious diseases in humans and pigs, but there are few studies investigating the airborne spread of the virus. In January 2011, a swine-origin H1N1 epidemic emerged in eastern China that rapidly spread to neighboring farms, likely by aerosols carried by the wind. METHODS: In this study, quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect viruses in air samples from pig farms. Based on two aerosol infection models (Pig and guinea pig), we evaluated aerosol transmission and infection of the novel S-O 2009 IV isolate. RESULTS: Three novel S-O 2009 IV were isolated from the diseased pig. The positive rate and viral loads of air samples were 26.1% and 3.14-5.72 log10copies/m³ air, respectively. In both pig and guinea pig infection models, the isolate (A/swine/Shandong/07/2011) was capable of forming aerosols and infected experimental animals at a range of 2.0-4.2 m by aerosols, but aerosol route was less efficient than direct contact. CONCLUSIONS: The results indicated that S-O 2009 IV is able to be aerosolized by infected animals and to be transmitted to susceptible animals by airborne routes.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Infecções por Orthomyxoviridae/transmissão , Doenças dos Suínos/transmissão , Microbiologia do Ar , Animais , China , Modelos Animais de Doenças , Cobaias , Infecções por Orthomyxoviridae/virologia , Reação em Cadeia da Polimerase em Tempo Real , Suínos , Doenças dos Suínos/virologia
10.
Environ Pollut ; 179: 19-26, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23639743

RESUMO

With the open-top chambers (OTCs) in situ in Yangtze River Delta, China in 2007 and 2008, the effects of elevated O3 exposure on nutrient elements and quality of winter wheat and rice grain were investigated. Grain yield per plant of winter wheat and rice declined in both years. The N and S concentrations increased under elevated O3 exposure in both years and C-N ratios decreased significantly. The concentrations of K, Ca, Mg, P, Mn, Cu and Zn in winter wheat and the concentrations of Mg, K, Mn and Cu in rice increased. The concentrations of protein, amino acid and lysine in winter wheat and rice increased and the concentration of amylose decreased. The increase in the nutrient concentration was less than the reduction of grain yield in both winter wheat and rice, and, hence, the absolute amount of the nutrients was reduced by elevated O3.


Assuntos
Poluentes Atmosféricos/toxicidade , Valor Nutritivo , Oryza/efeitos dos fármacos , Ozônio/toxicidade , Triticum/efeitos dos fármacos , China , Monitoramento Ambiental , Oryza/fisiologia , Estações do Ano , Triticum/fisiologia
11.
Huan Jing Ke Xue ; 34(1): 373-8, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23487964

RESUMO

Rapid increase of the urban impervious underlying surfaces causes a great increase of urban runoff and the accumulation of pollutants on the roof and road surfaces brings many pollutants into the drainage system with the runoff, and it thus becomes a great threat to the urban water environment. To know the runoff pollution process and to build scientific basis for pollutant control, runoff processes from the roof and road surfaces were monitored and analyzed from 2004 to 2006, and the runoff EMC (Event Mean Concentration) was calculated. It was found that two types of runoff were seriously polluted by COD and TN. The COD and TN of roof runoff exceeded the fifth level of the surface water environmental quality standard (GB 3838-2002) by 3.64 and 4.80 times, respectively, and the COD and TN of road runoff exceeded by 3.73 and 1.07 times, respectively. M (V) curve was used to determine the relation between runoff volume and runoff pollution load. Various degrees of the first flush phenomenon were found for TSS, COD, TN and TP in roof runoff. But this phenomenon occurred only for TSS and TP of the road runoff, and on the whole it was not obvious. Properties of the underlying surfaces, rainfall intensity, and pollutant accumulation are all important factors affecting the roof and road runoff pollutant emission characteristics.


Assuntos
Cidades , Chuva , Movimentos da Água , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental
12.
Huan Jing Ke Xue ; 33(7): 2251-8, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-23002598

RESUMO

Based on the investigation of water quality of Panxi River in different seasons, 2010, we assessed the diurnal variation of water quality in different seasons and the characteristics of water quality changes within a day by using non-parametric test, analysis of variance and grey relationship analysis. The results showed that the differences were not significant for Zn and Cu (P > 0.05), but significant differences existed among the pH, EC, DO, COD, TP, TSS, BOD5, NO(3-)-N, TN, NH(4+)-N, Pb and Cd contents. It showed that the minimum DO concentration occurred in winter, and the maximum of BOD5, COD and TOC concentrations occurred in winter, and the maximum NO(3-)-N concentration occurred in summer and the minimum TN, NH(4+)-N and TP concentrations occurred in summer. The diurnal variation of dissolved heavy metals showed relatively larger fluctuations in different seasons. The diurnal variation of different water quality parameters presented distinct patterns: diurnal variation of organic pollutants and nutrients showed the peak at 12:00 to 16:00 and dissolved heavy metals peaked at 12:00. The results of grey relationship analysis for surface water indicated that the water quality in spring was in the II class at 06:00 and 08:00 and was inferior to theV class for the rest hours; and the water quality in summer was in the II class; and the water quality in autumn was inferior to the V class at 06:00 and 16:00 and was in the II class for the rest hours; and the water quality in winter was in the II class at 08:00 and was inferior to the V class for the rest hours.


Assuntos
Monitoramento Ambiental , Rios , Poluentes Químicos da Água/análise , Qualidade da Água , China , Cidades , Estações do Ano
13.
Environ Pollut ; 171: 118-25, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22892574

RESUMO

The effects of a continuing rise of ambient ozone on crop yield will seriously threaten food security in China. In the Yangtze River Delta, a rapidly developing and seriously air polluted region in China, innovative open-top chambers have been established to fumigate winter wheat and rice in situ with elevated O(3). Five years of study have shown that the yields of wheat and rice decreased with increasing O(3) concentration. There were significant relationships between the relative yield and AOT40 (accumulated hourly O(3) concentration over 40 ppb) for both winter wheat and rice. Winter wheat was more sensitive to O(3) than rice. O(3)-induced yield declines were attributed primarily to 1000-grain weight and harvest index for winter wheat, and attributed primarily to grain number per panicle and harvest index for rice. Control of ambient O(3) pollution and breeding of O(3) tolerant crops are urgent to guarantee food security in China.


Assuntos
Poluentes Atmosféricos/análise , Oryza/química , Ozônio/análise , Triticum/química , Poluição do Ar/estatística & dados numéricos , China , Monitoramento Ambiental , Estações do Ano
14.
Huan Jing Ke Xue ; 33(4): 1114-21, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22720554

RESUMO

Based on the investigation of water quality of Panxi River in spring, 2010, we assessed the diurnal variation of water quality in spring and the characteristics of water quality changes within a day by using non-parametric test, analysis of variance and grey relationship analysis. The results showed that the differences were not significant for t, DO, COD, Pb, Cd, Zn and Cu (P > 0.05) in upstream, midstream and downstream, but significant difference existed among the pH, EC, TP, TSS, BOD5, NO3(-) -N, TN and NH4(+) -N contents. The diurnal variation of different water quality parameters presented distinct patterns: TN, TP and EC increased wavelike with time in upstream, fluctuated less in middle and showed the "single-peak single-valley" pattern in downstream, with the peak at 12:00. The diurnal variation of COD showed that "single-peak" pattern and with the peak at 10:00 in upstream and midstream and peak at 12:00 in downstream. The concentrations of Pb, Cd, Zn and Cu were low and peak at 12:00 in midstream; The grey relationship analysis indicated that the water quality in upstream was inferior to the V class of surface water at 18:00 and 20:00 and were in the II class of surface water for the rest hours, and the water quality in midstream was inferior to the V class of surface water at 12:00 and were in the II class of surface water for the rest hours; and the water quality in downstream was inferior to the V class of surface water all time during investigation.


Assuntos
Monitoramento Ambiental , Rios , Poluentes Químicos da Água/análise , Qualidade da Água , China , Cidades , Estações do Ano
15.
Huan Jing Ke Xue ; 33(1): 71-5, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22452191

RESUMO

The natural rainwater and stormwater runoff samples from three underlying surfaces (rooftop, campus road and ring road) were sampled and analyzed from July to October, 2010 in Beijing. Eight rainfall events were collected totally and thirteen water quality parameters were measured in each event. Grey relationship analysis and principal component analysis were applied to assess composite water quality and identify the main pollution sources of stormwater runoff. The results show that the composite water quality of ring road runoff is mostly polluted, and then is rooftop runoff, campus road runoff and rainwater, respectively. The composite water quality of ring road runoff is inferior to V class of surface water, while rooftop runoff, campus road runoff and rainwater are in II class of surface water. The mean concentration of TN and NH4(+)-N in rainwater and runoff is 5.49-11.75 mg x L(-1) and 2.90-5.67 mg x L(-1), respectively, indicating that rainwater and runoff are polluted by nitrogen (N). Two potential pollution sources are identified in ring road runoff: (1) P, SS and organic pollutant are possibly related to debris which is from vehicle tyre and material of ring road; (2) N and dissolved metal have relations with automobile exhaust emissions and bulk deposition.


Assuntos
Chuva , Movimentos da Água , Poluentes Químicos da Água/análise , Qualidade da Água , Água/análise , China , Cidades , Monitoramento Ambiental , Nitrogênio/análise , Compostos de Amônio Quaternário/análise , Poluição da Água/prevenção & controle
16.
Huan Jing Ke Xue ; 33(1): 76-82, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22452192

RESUMO

By investigating surface runoff from urban roadway in Chongqing, we assessed the characteristics of surface runoff pollution and the effect of rainfall intensity and antecedent dry weather period on water quality. Using multivariate statistical analysis of data of runoff quality, potential pollutants discharged from urban roadway runoff were identified. The results show that the roadway runoff has high levels of COD, TP and TN, the EMC were 60.83-208.03 mg x L(-1), 0.47-1.01 mg x L(-1) and 2.07-5.00 mg x L(-1) respectively, being the main pollutants; The peaks of pollutant concentration are ahead of or synchronous with the peak of runoff volume; the peaks of pollutant concentrations are mostly occurred within 10 minutes of rainfall. The heavy metal concentrations fluctuate dentately during runoff proceeding. Two potential pollution sources to urban roadway runoff apportioned by using principal component analysis are: vehicle's traffic loss and atmospheric dry and wet deposition, and municipal wastes.


Assuntos
Monitoramento Ambiental , Chuva/química , Movimentos da Água , Poluentes Químicos da Água/análise , China , Cidades , Metais Pesados/análise , Análise Multivariada , Análise de Componente Principal
17.
J Environ Sci (China) ; 24(12): 2104-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23534206

RESUMO

The significant warming in urban environment caused by the combined effects of global warming and heat island has stimulated widely development of urban vegetations. However, it is less known of the climate feedback of urban lawn in warmed environment. Soil warming effect on net ecosystem exchange (NEE) of carbon dioxide during the transition period from winter to spring was investigated in a temperate urban lawn in Beijing, China. The NEE (negative for uptake) under soil warming treatment (temperature was about 5 degrees C higher than the ambient treatment as a control) was -0.71 micromol/(m2 x sec), the ecosytem was a CO2 sink under soil warming treatment, the lawn ecosystem under the control was a CO2 source (0.13 micromol/(m2 x sec)), indicating that the lawn ecosystem would provide a negative feedback to global warming. There was no significant effect of soil warming on nocturnal NEE (i.e., ecosystem respiration), although the soil temperature sensitivity (Q10) of ecosystem respiration under soil warming treatment was 3.86, much lower than that in the control (7.03). The CO2 uptake was significantly increased by soil warming treatment that was attributed to about 100% increase of alpha (apparent quantum yield) and Amax (maximum rate of photosynthesis). Our results indicated that the response of photosynthesis in urban lawn is much more sensitive to global warming than respiration in the transition period.


Assuntos
Dióxido de Carbono/metabolismo , Ecossistema , Temperatura Alta , Estações do Ano , Solo , Respiração Celular , Cidades , Mudança Climática , Fotossíntese , Poaceae/metabolismo
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