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1.
J Med Virol ; 96(5): e29650, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38727133

RESUMO

To analyze the epidemiological characteristics of group A rotavirus (RVA) diarrhea in Beijing between 2019 and 2022 and evaluate the effectiveness of the RV5 vaccine. Stool specimens were collected from patients with acute diarrhea, and RVA was detected and genotyped. The whole genome of RVA was sequenced by fragment amplification and Sanger sequencing. Phylogenetic trees were constructed using Bayesian and maximum likelihood methods. Descriptive epidemiological methods were used to analyze the characteristics of RVA diarrhea. Test-negative design was used to evaluate the vaccine effectiveness (VE) of the RV5. Compared with 2011-2018, RVA-positive rates in patients with acute diarrhea under 5 years of age and adults decreased significantly between 2019 and 2022, to 9.45% (249/634) and 3.66% (220/6016), respectively. The predominant genotype of RVA had changed from G9-VIP[8]-III between 2019 and 2021 to G8-VP[8]-III in 2022, and P[8] sequences from G8-VP[8]-III strains formed a new branch called P[8]-IIIb. The complete genotype of G8-VP[8]-III was G8-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2. The VE of 3 doses of RV5 was 90.4% (95% CI: 28.8%-98.7%) against RVA diarrhea. The prevalence of RVA decreased in Beijing between 2019 and 2022, and the predominant genotype changed to G8P[8], which may be related to RV5 vaccination. Continuous surveillance is necessary to evaluate vaccine effectiveness and improve vaccine design.


Assuntos
Diarreia , Fezes , Genótipo , Filogenia , Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Humanos , Rotavirus/genética , Rotavirus/classificação , Rotavirus/imunologia , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Infecções por Rotavirus/prevenção & controle , Diarreia/virologia , Diarreia/epidemiologia , Vacinas contra Rotavirus/administração & dosagem , Vacinas contra Rotavirus/imunologia , Pré-Escolar , Prevalência , Pequim/epidemiologia , Masculino , Lactente , Feminino , Adulto , Fezes/virologia , Pessoa de Meia-Idade , Criança , Adulto Jovem , Adolescente , Eficácia de Vacinas , Idoso , Genoma Viral , Recém-Nascido
2.
J Med Virol ; 95(3): e28627, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36856149

RESUMO

New norovirus (NoV) variants emerge often leading to increased acute gastroenteritis outbreaks and outpatient visits. However, these increases are rarely quantified. Between September 2011 and August 2018, we included a total of 133 131 acute diarrhoea cases in 11 enteric disease outpatient clinics which were open all year round in Beijing. Over the same period, the etiology surveillance for acute diarrhoea was conducted, a total of 13 139 specimens were collected and tested, and 16.84% (2213/13 139) of all specimens were NoV-positive. The partial VP1 genes were successfully sequenced in 965 NoV strains. GII.4 Sydney, GII.17, and GII.2 predominated in 2012-2013, 2014-2015, and 2016-2017, respectively. We estimated the excess NoV-associated acute diarrhoea cases using the adjusted Serfling regression model, and three excess periods were found, corresponding to the predominance periods of GII.4 Sydney, GII.17 and GII.2, respectively, represented increases of 180.5% (95% confidence interval [CI]: 115.0%-246.0%), 114.7% (95% CI: 66.4%-163.1%) and 152.6% (95% CI: 100.2%-205.0%), compared with the baseline level. New NoV variants often caused an excess in their first year of predominance, and the excess periods of NoV-associated acute diarrhoea cases coincided with the predominance periods of NoV variants.


Assuntos
Infecções por Caliciviridae , Norovirus , Humanos , Pequim/epidemiologia , Norovirus/genética , Genótipo , Infecções por Caliciviridae/epidemiologia , Filogenia , Diarreia/epidemiologia , China/epidemiologia , Fezes
3.
J Med Virol ; 95(10): e29153, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37804388

RESUMO

The transmissibility is a crucial feature for norovirus, yet its quantitative estimation has been limited. Our objective was to estimate the basic reproduction number (R0 ) of norovirus and investigate its variation characteristics. Norovirus outbreaks reported from September 2016 to August 2021 in Beijing were analyzed. The susceptible-infected-removed compartment model was established to estimate R0 . Linear regression models and logistic regression models were used to explore the factors affecting the transmissibility of norovirus. The overall median R0 of norovirus was estimated as 2.1 (interquartile range [IQR] 1.8-2.5), with 650 norovirus outbreaks. The transmissibility of norovirus varied by year, outbreak setting and genotype. The R0 of norovirus during September 2019 to August 2020 (median 2.1, IQR 1.8-2.4) and September 2020 to August 2021 (median 2.0, IQR 1.7-2.3) was lower than that of September 2016 to August 2017 (median 2.3, IQR 1.8-2.7) (ß = 0.94, p = 0.05; ß = 0.93, p = 0.008). The R0 of norovirus for all other settings was lower than that for kindergarten (median 2.4, IQR 2.0-2.9) (primary school: median 2.0, IQR 1.7-2.4, ß = 0.94, p = 0.001; secondary school: median 1.7, IQR 1.5-2.0, ß = 0.87, p < 0.001; college: median 1.7, IQR 1.5-1.8, ß = 0.89, p = 0.03; other closed settings: median 1.8, IQR 1.5-2.0, ß = 0.90, p = 0.004). GⅡ.2[P16] outbreaks had a median R0 of 2.2 (IQR 1.8-2.7), which was higher than that for GⅡ.6[P7] outbreaks (median 1.8, IQR: 1.8-2.0, odds ratio = 0.19, p = 0.03; GⅡ.2[P16] as reference) and mixed-genotype outbreaks (median 1.7, IQR: 1.5-1.8, ß = 0.92, p = 0.02; mixed-genotype as reference). In kindergartens and primary schools, norovirus shows increased transmissibility, emphasizing the vulnerable population and high-risk settings. Furthermore, the transmissibility of norovirus may change over time and with virus evolution, necessitating additional research to uncover the underlying mechanisms.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Humanos , Pequim/epidemiologia , Norovirus/genética , Gastroenterite/epidemiologia , Infecções por Caliciviridae/epidemiologia , China/epidemiologia , Surtos de Doenças , Genótipo
4.
BMC Infect Dis ; 23(1): 270, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37131193

RESUMO

BACKGROUND: Noroviruses are a leading cause of acute gastroenteritis (AGE) worldwide. The geographical characteristics of norovirus outbreaks in Beijing and their influencing factors remain unknown. This study aimed to explore the spatial distributions, geographical characteristics, and influencing factors of norovirus outbreaks in Beijing, China. METHODS: Epidemiological data and specimens were collected through the AGE outbreak surveillance system in all 16 districts of Beijing. Data on spatial distribution, geographical characteristics, and influencing factors of norovirus outbreaks were analyzed using descriptive statistics methods. We measured spatial, geographical clustering of high- or low-value deviance from random distribution using Z-scores and P-values as statistical significance measures with Global Moran's I statistics and Getis-Ord Gi in ArcGIS. Linear regression and correlation methods were used to explore influencing factors. RESULTS: Between September 2016 and August 2020, 1,193 norovirus outbreaks were laboratory-confirmed. The number of outbreaks varied seasonally, typically peaking in spring (March to May) or winter (October to December). Outbreaks primarily occurred around central districts at the town level, and spatial autocorrelation was evident in both the entire study period and in individual years. Hotspots of norovirus outbreaks in Beijing were primarily found in contiguous areas between three central districts (Chaoyang, Haidian, Fengtai) and four suburban districts (Changping, Daxing, Fangshan, Tongzhou). The average population numbers, mean number of all schools, and mean number of kindergartens and primary schools for towns in central districts and hotspot areas were higher than those in suburban districts and non-hotspot areas respectively. Additionally, population numbers and densities of kindergartens and primary schools were influencing factors at the town level. CONCLUSIONS: Hotspots of norovirus outbreaks in Beijing were in contiguous areas between central and suburban districts with high populations, and high kindergarten and primary school densities were the likely driving forces. Outbreak surveillance needs to focus on contiguous areas between central and suburban districts with increased monitoring, medical resources, and health education.


Assuntos
Infecções por Caliciviridae , Norovirus , Humanos , Pequim/epidemiologia , China/epidemiologia , Surtos de Doenças , Escolaridade , Infecções por Caliciviridae/epidemiologia
5.
Environ Geochem Health ; 45(5): 1793-1806, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35648327

RESUMO

Coal mine in arid and semi-arid area is one of the most severely degraded ecosystems on the earth. The continuous decrease in groundwater level caused by coal mining will inevitably affect biogeochemical environment of the vadose zone, and then lead to the replacement of surface vegetation. Yimin open-pit coal mine was taken as an example to reveal the relationship between the groundwater depth and soil water content (SWC), soil salt content, soil electrical conductivity (SEC), soil organic matter (SOM), soil available potassium (SAK), soil available nitrogen (SAN), vegetation coverage, aboveground biomass and species richness. The results show that, the change of groundwater depth can affect soil properties and then change the characteristics of surface vegetation, and the change of surface vegetation can also react on soil properties. Vegetation coverage and aboveground biomass are negatively correlated with groundwater depth, and positively correlated with SWC, SEC, SOM and SAK. The shallow groundwater table is conducive to the accumulation of SOM, so that the surface biomass and vegetation coverage are high. The higher the surface biomass, the more the SAN is absorbed. Under natural conditions, the relative strength of biological nitrogen fixation and plant absorption determine the content of SAN. In the research area, when the depth of groundwater is less than 0.4 m will cause soil salinization, then lead to low species richness; Species richness is exponentially correlated with groundwater depth and decreases with the increase in groundwater depth.


Assuntos
Ecossistema , Água Subterrânea , Pradaria , Solo/química , Água , Carvão Mineral , China
6.
Neuroimage ; 261: 119513, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35882271

RESUMO

For decades, it has been assumed that when humans retrieve information from long-term memory (LTM), information need first to be brought back into working memory (WM). However, as WM capacity is limited, it is unclear what happens if information from LTM needs to be retrieved while WM is fully engaged? To address this question, observers had to retrieve colors from LTM while WM storage capacity was fully engaged. The behavioral results showed that retrieving information from LTM is possible even when WM capacity is fully occupied. Additional evidence from electroencephalogram (EEG) confirmed that WM was fully engaged as the suppression of alpha oscillation reached its maximum when memorizing the maximum amount of information into WM; yet the suppression in alpha oscillation was even further amplified when items were retrieved simultaneously from LTM, providing a neural signature of additional LTM retrieval capacity above and beyond the maximum WM capacity. Together, our findings indicate that information retrieved from LTM does not always have to be brought back into WM, but instead might be accessed through a different mechanism when WM is fully engaged.


Assuntos
Memória de Longo Prazo , Memória de Curto Prazo , Eletroencefalografia , Humanos
7.
J Med Virol ; 93(11): 6191-6199, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34028862

RESUMO

Group A rotavirus (RVA) is one of the most common causes of severe diarrhea in children worldwide. However, RVA is also an important pathogen causing adult diarrhea, with higher infection rates in older patients. To provide evidence for rotavirus epidemic control and to inform vaccine development, we analyzed the molecular epidemiology of RVA among adult outpatients with diarrhea in Beijing from 2011 to 2018. Stool specimens were collected monthly from 14 districts. RVA was detected using enzyme-linked immunosorbent assay and real-time reverse-transcription polymerase chain reaction (RT-PCR). Genotyping of rotavirus was performed using multiplex semi-nested RT-PCR. Phylogenetic analysis was performed using maximum likelihood methods implemented in MEGA software (version 6.06). Logistic regression and chi-square tests were used to assess differences among age groups, districts, years, and genotype distributions. The prevalence of rotavirus was 10.16% (1310 of 12,893) among adult outpatients with diarrhea from 2011 to 2018 in Beijing. The highest prevalence (13.74%, 600 of 4367) was observed among those aged 41 to 65 years. November, December, and January had the highest positive detection rates. In 2011, G3P[8] and G9P[8] were the dominant genotypes. Starting from 2012, G9P[8] became the dominant genotype. Most G9 strains belonged to the G9-VI clade. Most P[8] strains belonged to the P[8]-III clade. RVA is a major cause of adult diarrhea in Beijing. Continuous molecular surveillance is needed, and transmission of rotavirus between children and adults should be investigated further.


Assuntos
Diarreia/epidemiologia , Infecções por Rotavirus/epidemiologia , Rotavirus/genética , Adolescente , Adulto , Idoso , Antígenos Virais/genética , Pequim/epidemiologia , Diarreia/virologia , Fezes/virologia , Feminino , Genótipo , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Rotavirus/patogenicidade , Infecções por Rotavirus/virologia , Adulto Jovem
8.
BMC Infect Dis ; 18(1): 135, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29558885

RESUMO

BACKGROUND: Human adenovirus (HAdV)-associated acute conjunctivitis is a common infectious disease and causes significant morbidity among residents in Beijing, China. However, little is known about the epidemiology and type distribution of acute adenoviral conjunctivitis in Beijing. METHODS: Acute conjunctivitis surveillance was conducted in 18 hospitals in Beijing from July through October during 2011-2013. HAdVs were detected by PCR from eye swab and types were determined by partial hexon and fiber gene sequencing. Risk factors associated with adenoviral conjunctivitis were analyzed. RESULTS: Of 876 conjunctivitis cases, 349 (39.8%) were HAdV positive. HAdV detection was most common in conjunctivitis patients aged 18-40 years; patients with contact history with a conjunctivitis case; patients with specimen collected on days 4-6 post symptom onset and patients who worked in food service as catering attendants. Fifteen types were identified among adenoviral conjunctivitis cases. Five HAdV types (HAdV-4, - 37, - 53, - 64 and - 8) accounted for 81.1% of all adenoviral conjunctivitis cases. HAdV-37, - 4 and - 53 were the most common types associated with adenoviral conjunctivitis in 2011, 2012 and 2013, respectively. CONCLUSION: Multiple HAdV types were associated with acute conjunctivitis in Beijing. Predominant types associated with adenoviral conjunctivitis circulating in Beijing varied from year to year.


Assuntos
Adenoviridae/isolamento & purificação , Conjuntivite/etiologia , Doença Aguda , Adenoviridae/genética , Infecções por Adenovirus Humanos/complicações , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Conjuntivite/epidemiologia , Conjuntivite/virologia , DNA Viral/isolamento & purificação , DNA Viral/metabolismo , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fatores de Risco , Adulto Jovem
9.
BMC Infect Dis ; 18(1): 497, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30285635

RESUMO

BACKGROUND: Rotavirus is a leading cause of severe diarrheal disease, and one of the common causes of death in children aged under five years old. The dominant epidemic strains may change in different years in the same area. In order to provide evidence for rotavirus epidemic control and inform vaccine development, we analyzed epidemiological patterns and genetic characteristics of rotavirus in Beijing during 2011-2016. METHODS: Stool specimens of outpatient children under five years old were collected from three children's hospitals on a weekly basis. Group A rotavirus antigens were detected using enzyme-linked immunosorbent assay (ELISA) kit. The partial VP4 genes and VP7 genes of rotavirus were both amplified and sequenced. Genotyping and phylogenetic analyses were performed. Logistic regression and Chi-square tests were performed to determine differences across age groups, districts and years in rotavirus prevalence and genotype distribution. RESULTS: A total of 3668 stool specimens from children with acute diarrhea identified through hospital-based surveillance were collected from 2011 to 2016 in Beijing. A total of 762 (20.8%) specimens tested positive for rotavirus. The rotavirus-positive rate was highest among the 1-2 years old age group (29.0%, 310/1070). November, December and January were the highest rotavirus-positive rate months each year. G9 was the most common G genotype (64.4%, 461/716), and P [8] was the most common P genotype (87.0%, 623/716) among the 716 rotavirus-positive specimens. G9P [8], G3P [8] and G2P [4] were the most common strains. The rotavirus-positive rates of samples in 2012 and 2013 were higher than that in 2011, and the dominant genotype changed from G3P [8] to G9P [8] in 2012 and 2013. VP7 gene sequences of G9 strains in this study clustered into two main lineages. Most of the G9 strains exhibited the highest nucleotide similarity (99.1%~ 100.0%) to the strain found in Japan (MI1128). VP4 gene sequences of P [8] strains were almost P[8]b. CONCLUSIONS: Rotavirus accounted for more than one fifth of childhood diarrhea in Beijing during the study period. Targeted measures such as immunization with effective rotavirus vaccines should be carried out to reduce the morbidity and mortality due to rotavirus.


Assuntos
Diarreia/virologia , Filogenia , Infecções por Rotavirus/epidemiologia , Rotavirus/genética , Antígenos Virais/genética , Pequim/epidemiologia , Proteínas do Capsídeo/genética , Pré-Escolar , Diarreia/epidemiologia , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Japão , Masculino , Prevalência , Rotavirus/patogenicidade , Infecções por Rotavirus/virologia
10.
BMC Infect Dis ; 16: 206, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-27184561

RESUMO

BACKGROUND: The incidence of hand, foot, and mouth disease (HFMD) is extremely high, and has constituted a huge disease burden throughout Beijing in recent years. This study aimed to determine the spatiotemporal distribution and epidemic characteristics of HFMD. METHODS: Descriptive statistics was used to analyze the data and estimate the epidemic peaks in 2009-2014. Space-time scanning detected spatiotemporal clusters and identified high-risk locations. Global and local Moran's I statistics were used to measure the spatial autocorrelation. Geocoding was performed in ArcGIS, based on the present address codes of the patients and the centroids of the towns. Maps were created in ArcGIS to show the geographic spread of HFMD. RESULTS: In total, 220,451probable cases of HFMD were reported in Beijing between January 2009 and December 2014: 12,749 (5.78 %) were laboratory confirmed, and 35 (0.02 %) were fatal. The median age of reported cases was 3.12 years (interquartile range 1.96-4.39). Coxsackievirus A16 (CV-A16), enterovirus 71 (EV-A71), and other enteroviruses accounted for 39.31, 35.36, and 25.33 % of the 12,749 confirmed cases, respectively. Many more severe cases were caused by EV-A71 (χ (2) = 186.41, df = 1, P < 0.001) and other enteroviruses (χ (2) = 156.44, df = 1, P < 0.001) than by CV-A16. A large single distinct peak occurred between May and July each year. Spatiotemporal clusters of HFMD were identified in Beijing during 2009-2014. The most likely clusters were detected and tended to move from the southwest (Fengtai and Daxing) southeastwards to Daxing and Tongzhou in 2009-2014. The incidence of HFMD was not randomly distributed, but showed global and local spatial autocorrelations. CONCLUSIONS: There were obvious spatiotemporal clusters of HFMD in Beijing in 2009-2014. High-incidence areas mainly occurred at the junctions of urban and rural zones. More attention should be paid to the epidemiological and spatiotemporal characteristics of HFMD to establish new strategies for its control. Health issues should be especially promoted in kindergartens and at urban-rural junctions.


Assuntos
Enterovirus/isolamento & purificação , Doença de Mão, Pé e Boca/diagnóstico , Animais , Pequim/epidemiologia , Pré-Escolar , China/epidemiologia , Enterovirus/classificação , Enterovirus/genética , Epidemias , Feminino , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Incidência , Lactente , Masculino , Gravidez , Análise Espacial
11.
J Med Virol ; 87(12): 2040-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25982899

RESUMO

Human caliciviruses (HuCVs), including noroviruses (NoVs) and sapoviruses (SaVs), are the most common cause of diarrhea in adults and the second most common cause of diarrhea in children. Between April 2011 and March 2013, 3,832 fecal specimens were collected from outpatients with diarrhea from 17 hospitals in Beijing, China, and 669 specimens (17.5%) were positive for HuCV. Of the 287 HuCV-positive specimens, 263 (91.6%) were identified to be NoV, 23 (8.0%) were identified to be SaV, and one (0.3%) was identified to be a mixed infection of NoV and SaV. Of the 263 NoV-positive specimens, 237 (90.1%) were NoV GII, 21 (8.0%) were NoV GI, and 5 (1.9%) were a combination of NoV GI and GII. Among the 216 sequenced GII-positive samples, GII.4 was the most common genotype (70.4%, 152/216), followed by GII.13 (9.3%, 20/216). GII.4 Sydney_2012 was first detected in August 2012 and replaced GII.4 Den Haag_2006b as the predominant variant between September 2012 and March 2013. With the emergence of the GII.4 Sydney_2012 variant, 44.6% more patients with diarrhea visited the 17 hospitals (9,931 cases) than in the previous year (6,866 cases) between October and December 2012.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Diarreia/epidemiologia , Diarreia/virologia , Norovirus/isolamento & purificação , Sapovirus/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pequim/epidemiologia , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologia , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Norovirus/classificação , Norovirus/genética , Pacientes Ambulatoriais , Prevalência , Adulto Jovem
12.
BMC Infect Dis ; 15: 574, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26678989

RESUMO

BACKGROUND: Norovirus (NoV) is a leading cause of sporadic cases and outbreaks of acute gastroenteritis (AGE). Increased NoV activity was observed in Beijing, China during winter 2014-2015; therefore, we examined the epidemiological patterns and genetic characteristics of NoV in the sporadic cases and outbreaks. METHODS: The weekly number of infectious diarrhea cases reported by all hospitals in Beijing was analyzed through the China information system for disease control and prevention. Fecal specimens were collected from the outbreaks and outpatients with AGE, and GI and GII NoVs were detected using real time reverse transcription polymerase chain reaction. The partial capsid genes and RNA-dependent RNA polymerase (RdRp) genes of NoV were both amplified and sequenced, and genotyping and phylogenetic analyses were performed. RESULTS: Between December 2014 and March 2015, the number of infectious diarrhea cases in Beijing (10,626 cases) increased by 35.6% over that of the previous year (7835 cases), and the detection rate of NoV (29.8%, 191/640) among outpatients with AGE was significantly higher than in the previous year (12.9%, 79/613) (χ(2) = 53.252, P < 0.001). Between November 2014 and March 2015, 35 outbreaks of AGE were reported in Beijing, and NoVs were detected in 33 outbreaks, all of which belonged to the GII genogroup. NoVs were sequenced and genotyped in 22 outbreaks, among which 20 were caused by a novel GII.17 strain. Among outpatients with AGE, this novel GII.17 strain was first detected in an outpatient in August 2014, and it replaced GII.4 Sydney_2012 as the predominant variant between December 2014 and March 2015. A phylogenetic analysis of the capsid genes and RdRp genes revealed that this novel GII.17 strain was distinct from previously identified GII variants, and it was recently designated as GII.P17_GII.17. This variant was further clustered into two sub-groups, named GII.17_2012 and GII.17_2014. During winter 2014-2015, GII.17_2014 caused the majority of AGE outbreaks in China and Japan. CONCLUSIONS: During winter 2014-2015, a novel NoV GII.17 variant replaced the GII.4 variant Sydney 2012 as the predominant strain in Beijing, China and caused increased NoV activity.


Assuntos
Infecções por Caliciviridae/epidemiologia , Gastroenterite/virologia , Norovirus/genética , Norovirus/patogenicidade , Pequim/epidemiologia , Infecções por Caliciviridae/virologia , Proteínas do Capsídeo/genética , Diarreia/epidemiologia , Diarreia/virologia , Surtos de Doenças , Gastroenterite/epidemiologia , Hospitais , Humanos , Pacientes Ambulatoriais , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano
13.
ScientificWorldJournal ; 2014: 183457, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25126593

RESUMO

In the rubber dam's impact area, the groundwater total hardness (TH) has declined since 2000, ultimately dropping to 100-300 mg/L in 2012. pH levels have shown no obvious changes. NH4-N concentration in the groundwater remained stable from 2000 to 2006, but it increased from 2007 to 2012, with the largest increase up to 0.2 mg/L. NO3-N concentration in the groundwater generally declined in 2000-2006 and then increased from 2007; the largest increase was to 10 mg/L in 2012. Total dissolved solids (TDS) of the groundwater showed a general trend of decline from 2000 to 2009, but levels increased after 2010, especially along the south bank of the Luohe River where the largest increase recorded was approximately 100 mg/L. This study has shown that the increases in the concentrations of NH4-N and NO3-N were probably caused by changes in groundwater levels. Nitrates adsorbed by the silt clay of aeration zone appear to have entered the groundwater through physical and chemical reactions. TDS increased because of groundwater evaporation and some soluble ions entered the groundwater in the unsaturated zone. The distance of the contaminant to the surface of the aquifer became shorter due to the shallow depth of groundwater, resulting in the observed rise in pollutant concentrations more pronounced.


Assuntos
Meio Ambiente , Água Subterrânea/química , Borracha/química , Movimentos da Água , Poluentes Químicos da Água/análise , Compostos de Amônio/análise , Cálcio/análise , China , Fenômenos Geológicos , Concentração de Íons de Hidrogênio , Nitratos/análise
14.
Elife ; 122024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747572

RESUMO

Working memory enables us to bridge past sensory information to upcoming future behaviour. Accordingly, by its very nature, working memory is concerned with two components: the past and the future. Yet, in conventional laboratory tasks, these two components are often conflated, such as when sensory information in working memory is encoded and tested at the same location. We developed a task in which we dissociated the past (encoded location) and future (to-be-tested location) attributes of visual contents in working memory. This enabled us to independently track the utilisation of past and future memory attributes through gaze, as observed during mnemonic selection. Our results reveal the joint consideration of past and future locations. This was prevalent even at the single-trial level of individual saccades that were jointly biased to the past and future. This uncovers the rich nature of working memory representations, whereby both past and future memory attributes are retained and can be accessed together when memory contents become relevant for behaviour.


Assuntos
Memória de Curto Prazo , Percepção Visual , Memória de Curto Prazo/fisiologia , Humanos , Masculino , Percepção Visual/fisiologia , Feminino , Adulto , Adulto Jovem , Movimentos Sacádicos/fisiologia
15.
Prog Neurobiol ; 224: 102433, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36907349

RESUMO

The lateralisation of 8-12 Hz alpha activity is a canonical signature of human spatial cognition that is typically studied under strict fixation requirements. Yet, even during attempted fixation, the brain produces small involuntary eye movements known as microsaccades. Here we report how spontaneous microsaccades - made in the absence of incentives to look elsewhere - can themselves drive transient lateralisation of EEG alpha power according to microsaccade direction. This transient lateralisation of posterior alpha power occurs similarly following start and return microsaccades and is, at least for start microsaccades, driven by increased alpha power ipsilateral to microsaccade direction. This reveals new links between spontaneous microsaccades and human electrophysiological brain activity. It highlights how microsaccades are an important factor to consider in studies relating alpha activity - including spontaneous fluctuations in alpha activity - to spatial cognition, such as studies on visual attention, anticipation, and working memory.


Assuntos
Movimentos Sacádicos , Percepção Visual , Humanos , Percepção Visual/fisiologia , Movimentos Oculares , Encéfalo/fisiologia , Eletroencefalografia
16.
Infect Genet Evol ; 114: 105491, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37597645

RESUMO

Norovirus (NoV) is the leading pathogen responsible for global acute gastroenteritis (AGE) outbreaks and sporadic cases. NoV evolves through gene mutation and recombination, leading to the emergence of new strains capable of causing global epidemics. This study aimed to learn the epidemiological characteristics of 39 GI.6[P11] NoV outbreaks in Beijing, China, from 2016 to 2019 and to analyze the genetic diversity and phylogenetic process of GI.6[P11] strains. The Bayesian phylogenetic analysis of partial VP1 and RNA-dependent RNA polymerase (RdRp) genes showed that GI.6[P11] strains were clustered into four subclades. Eleven whole genome sequences were obtained through the amplicon sequencing with 16 pairs of newly designed primers. The phylogenetic trees based on the whole genome and ORF1, 2, and 3 showed that the clustering of the 11 strains was consistent with that of partial VP1 and RdRp genes. The Bayesian inference revealed that the most recent ancestor (TMRCA) for the four subclades of the phylogenetic tree based on the whole genome sequences was 2012.42, 2014.81, 2011.74, and 2015.53, respectively. The recombination sites of GI.6[P11] strains in Beijing were located near the ORF1/2 junction. The histo-blood group antigens (HBGA) binding sites of GI.6[P11] strains in Beijing were conserved and there were some unique amino acid mutations in non-structural proteins in the ORF1 region.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Humanos , Pequim/epidemiologia , Norovirus/genética , Filogenia , Teorema de Bayes , Gastroenterite/epidemiologia , China/epidemiologia , Genótipo , Surtos de Doenças , RNA Polimerase Dependente de RNA/genética , Recombinação Genética , Infecções por Caliciviridae/epidemiologia
17.
Infect Genet Evol ; 111: 105435, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37059255

RESUMO

We analyzed the prevalence and genotypes of Parechovirus A (PeV-A) in children with diarrhea in Beijing, China, 2017-2019. A total of 1734 stool samples collected from children <5 years of age with diarrhea were tested for the presence of PeV-A. Viral RNA was detected by real-time RT-PCR, and then genotyped by nested RT-PCR. We detected PeV-A in 93 (5.4%, 93/1734) samples, of which 87 could be genotyped by amplification of either the complete or partial VP1 region or the VP3/VP1 junction region. The median age of PeV-A infected children was 10 months. Most PeV-A infections were observed between August and November, with a peak in September. Seven known genotypes of PeV-A1A, -A1B, -A3, -A4, -A6, -A8 and -A11 were detected and PeV-A1B was the most prevalent genotype. Coinfection with other diarrheal viruses was observed in 30.1% (28/93) of PeV-A positive samples. All strains of PeV-A1A, -A1B, -A4 and -A6 obtained in this study contained the arginine-glycine-aspartic acid (RGD) motif, while all strains of PeV-A3, -A8 and -A11 lacked it. This study revealed a high genetic diversity of PeV-A circulating in Beijing and PeV-A11 was reported for the first time in children with diarrhea in China.


Assuntos
Parechovirus , Infecções por Picornaviridae , Humanos , Criança , Lactente , Pequim/epidemiologia , Parechovirus/genética , Prevalência , Infecções por Picornaviridae/epidemiologia , Diarreia/epidemiologia , China/epidemiologia , Genótipo , Variação Genética
18.
Nat Commun ; 13(1): 3503, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715471

RESUMO

Covert spatial attention is associated with spatial modulation of neural activity as well as with directional biases in fixational eye movements known as microsaccades. We studied how these two 'fingerprints' of attention are interrelated in humans. We investigated spatial modulation of 8-12 Hz EEG alpha activity and microsaccades when attention is directed internally within the spatial layout of visual working memory. Consistent with a common origin, spatial modulations of alpha activity and microsaccades co-vary: alpha lateralisation is stronger in trials with microsaccades toward versus away from the memorised location of the to-be-attended item and occurs earlier in trials with earlier microsaccades toward this item. Critically, however, trials without attention-driven microsaccades nevertheless show clear spatial modulation of alpha activity - comparable to trials with attention-driven microsaccades. Thus, directional biases in microsaccades correlate with neural signatures of spatial attention, but they are not necessary for neural modulation by spatial attention to be manifest.


Assuntos
Movimentos Sacádicos , Percepção Visual , Sinais (Psicologia) , Movimentos Oculares , Fixação Ocular , Humanos , Memória de Curto Prazo
19.
Chemosphere ; 301: 134657, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35447201

RESUMO

Globally, groundwater with high fluoride and arsenic receives extensive concern because of its wide distribution and great harm to human health caused by drinking water. In this paper, taking Tumochuan Plain in China as an example, based on hydrogeological investigation, groundwater flow system theory and hydro-chemical analysis methods were applied to reveal the mechanism of high fluoride and high arsenic in arid and semi-arid regions. In unconfined and confined groundwater of Tumochuan Plain, the highest concentration of fluoride is 7.2 and 11.2 mg/L respectively, and the highest concentration of total arsenic is 200.3 and 162.3 µg/L respectively. Fluoride in groundwater is mainly derived from the soluble fluoride in soil and aquifer medium. Because of the water-rock interaction, the alkaline environment caused by the hydrolysis of feldspar minerals in the central part of the plain has an important influence on the accumulation of F and As in this area. High fluoride water is formed in the alkaline environment (high pH values) of high concentration of Na+ and low concentration of Ca2+. The high arsenic groundwater is distributed in the alkaline reducing environment that the content of soluble salt in aquifer media is high (>200 mg/100 g dry soil). The reductive dissolution of iron and manganese oxides and competitive adsorption of HCO3- all contribute to a high level of arsenic in both unconfined and confined aquifers. The research results have important guiding significance for water supply safety and water quality improvement in arid-semiarid areas in the world with high fluoride and high arsenic groundwater distribution.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , China , Monitoramento Ambiental/métodos , Fluoretos/análise , Água Subterrânea/química , Solo , Poluentes Químicos da Água/análise
20.
Front Psychol ; 13: 932666, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35978799

RESUMO

Previous studies have demonstrated that inversion effect and left-side bias are stable expertise markers in Chinese character processing among adults. However, it is less clear how these markers develop early on (i.e., among primary school students). Therefore, this study aimed to investigate the development of the two markers by comparing primary school-aged students of three age groups (Grade 1, Grade 3, and Grade 5) and adults in tests of inversion effect (Experiment 1) and left-sided bias effect (Experiment 2). The results replicated that both effects during Chinese character processing were present among adults. However, more importantly, the effects were different among primary school-aged students in different grades: the inversion effect was found as early as in Grade 1, but the left-side bias effect did not emerge in Grade 1 and as approximated that of adults until Grade 3. The study suggested a potential dissociation in developing different aspects of expertise during Chinese character processing in early childhood.

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