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1.
Cardiovasc Res ; 116(6): 1097-1100, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32227090

RESUMO

A new type of pneumonia caused by a novel coronavirus SARS-CoV-2 outbreaks recently in China and spreads into many other countries. This disease, named as COVID-19, is similar to patients infected by SARS-CoV and MERS-CoV, and nearly 20% of patients developed severe condition. Cardiac injury is a prevalent complication of severe patients, exacerbating the disease severity in coronavirus disease 2019 (COVID-19) patients. Angiotensin-converting enzyme 2 (ACE2), the key host cellular receptor of SARS-CoV-2, has been identified in multiple organs, but its cellular distribution in human heart is not illuminated clearly. This study performed the first state-of-art single cell atlas of adult human heart, and revealed that pericytes with high expression of ACE2 might act as the target cardiac cell of SARS-CoV-2. The pericytes injury due to virus infection may result in capillary endothelial cells dysfunction, inducing microvascular dysfunction. And patients with basic heart failure disease showed increased ACE2 expression at both mRNA and protein levels, meaning that if infected by the virus these patients may have higher risk of heart attack and critically ill condition. The finding of this study explains the high rate of severe cases among COVID-19 patients with basic cardiovascular disease; and these results also perhaps provide important reference to clinical treatment of cardiac injury among severe patients infected by SARS-CoV-2.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/complicações , Cardiopatias/etiologia , Miocárdio/enzimologia , Peptidil Dipeptidase A/metabolismo , Pericitos/enzimologia , Pneumonia Viral/complicações , Betacoronavirus/metabolismo , Infecções por Coronavirus/virologia , Expressão Gênica , Perfilação da Expressão Gênica , Coração/virologia , Humanos , Pandemias , Peptidil Dipeptidase A/genética , Pericitos/virologia , Pneumonia Viral/virologia , Receptores Virais/genética , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo
2.
PLoS One ; 15(4): e0230295, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32298273

RESUMO

The new type of pneumonia caused by the SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2) has been declared as a global public health concern by WHO. As of April 3, 2020, more than 1,000,000 human infections have been diagnosed around the world, which exhibited apparent person-to-person transmission characteristics of this virus. The capacity of vertical transmission in SARS-CoV-2 remains controversial recently. Angiotensin-converting enzyme 2 (ACE2) is now confirmed as the receptor of SARS-CoV-2 and plays essential roles in human infection and transmission. In present study, we collected the online available single-cell RNA sequencing (scRNA-seq) data to evaluate the cell specific expression of ACE2 in maternal-fetal interface as well as in multiple fetal organs. Our results revealed that ACE2 was highly expressed in maternal-fetal interface cells including stromal cells and perivascular cells of decidua, and cytotrophoblast and syncytiotrophoblast in placenta. Meanwhile, ACE2 was also expressed in specific cell types of human fetal heart, liver and lung, but not in kidney. And in a study containing series fetal and post-natal mouse lung, we observed ACE2 was dynamically changed over the time, and ACE2 was extremely high in neonatal mice at post-natal day 1~3. In summary, this study revealed that the SARS-CoV-2 receptor was widely spread in specific cell types of maternal-fetal interface and fetal organs. And thus, both the vertical transmission and the placenta dysfunction/abortion caused by SARS-CoV-2 need to be further carefully investigated in clinical practice.


Assuntos
Infecções por Coronavirus/metabolismo , Relações Materno-Fetais , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/metabolismo , Vírus da SARS/metabolismo , Animais , Infecções por Coronavirus/genética , Humanos , Camundongos , Pandemias , Peptidil Dipeptidase A/genética , Pneumonia Viral/genética , Análise de Célula Única , Transcriptoma
4.
PeerJ ; 7: e8031, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31799071

RESUMO

Background: The Mosq-ovitrap (MOT) is currently used for routine surveillance of container-breeding Aedes in China. However, the effectiveness of monitoring Aedes albopictus using the MOT and other mosquito monitoring methods, such as the Ovitrap (OT) and the CO2-light trap (CLT), have not been extensively compared. Moreover, little is known about the spatial-temporal correlations of eggs with adult Ae. albopictus abundance among these three types of traps. Methods: Comparative field evaluation of MOT, OT and CLT for Ae. albopictus monitoring was conducted simultaneously at two city parks and three residential neighborhoods in downtown Shanghai for 8 months from April 21 to December 21, 2017. Results: Significantly more Ae. albopictus eggs were collected from both MOTs and OTs when traps remained in the field for 10 d or 7 d compared with 3 d (MOT: 50.16, 34.15 vs. 12.38 per trap, P < 0.001; OT: 3.98, 2.92 vs. 0.63 per trap, P < 0.001). Egg collections of MOTs were significantly greater than OTs for all three exposure durations (Percent positive: X 2 = 72.251, 52.420 and 51.429, P value all < 0.001; egg collections: t = 8.068, 8.517 and 10.021, P value all <0.001). Significant temporal correlations were observed between yields of MOT and CLT in all sampling locations and 3 different MOT exposure durations (correlation coefficient r ranged from 0.439 to 0.850, P values all < 0.05). However, great variation was found in the spatial distributions of Ae. albopictus density between MOT and CLT. MOT considerably underestimated Ae. albopictus abundances in areas with high Ae. albopictus density (>25.56 per day ⋅ trap by CLT). Conclusion: The MOT was more efficient than the OT in percent positive scores and egg collections of Ae. albopictus. The minimum length of time that MOTs are deployed in the field should not be less than 7 d, as Ae. albopictus collections during this period were much greater than for 3 d of monitoring. MOT considerably underestimated Ae. albopictus abundance in areas with high Aedes albopictus density compared to CLT. In areas with moderate Aedes albopictus densities, MOT results were significantly correlated with CLT catches.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31867287

RESUMO

Pancreatic cancer is a highly lethal disease, and most patients remain asymptomatic until the disease enters advanced stages. There is lack of knowledge in the pathogenesis, effective prevention and early diagnosis of pancreatic cancer. Recently, bacteria were found in pancreatic tissue that has been considered sterile before. The distribution of flora in pancreatic cancer tissue was reported to be different from normal pancreatic tissue. These abnormally distributed bacteria may be the risk factors for inducing pancreatic cancer. Therefore, studies on combined effect of multi-bacterial and multi-virulence factors may add to the knowledge of pancreatic cancer pathogenesis and aid in designing new preventive and therapeutic strategies. In this review, we outlined three oral bacteria associated with pancreatic cancer and their virulence factors linked with cancer.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31673353

RESUMO

Background: Annual influenza vaccination is the most effective way to prevent influenza. Influenza vaccines have traditionally included the hemagglutinins (HA) and neuraminidases (NA) from the two A viruses (H1N1 and H3N2) and either B Yamagata or B Victoria. Mismatches between circulating isolates of influenza B and the vaccines are very common. Taking 2017/2018 winter in northern hemisphere as an example, this study was designed to find out the reasons for mismatch between the trivalent influenza vaccine (TIV) and most of the epidemic isolates at that time, and to discuss if there are some optimized programs for seasonal influenza vaccines. Methods: HA and NA sequences of the seasonal isolates circulating from December 1, 2017 to February 28, 2018, and in the previously other 7 winters in northern hemisphere from Global Initiative on Sharing All Influenza Data (GISAID) and the influenza database of National Center for Biotechnology Information (NCBI). Phylogenetic trees and genetic distances were constructed or calculated by using MAFFT and MEGA 6.0 software. Results: Influenza B composition in the TIV recommendation mismatched most of circulating viruses in 2017/2018 winter; the vaccine strain was from the B/Victoria lineage, while most of epidemic isolates were from the B/Yamagata lineage. The epidemic lineage of influenza B reached its peak a little late in the previous winter might be responsible for this mismatch. During 2010-2018, the mean genetic distances between epidemic isolates of influenza A (H1N1 and H3N2) and the vaccines were no higher than 0.02375 ± 0.00341 in both HA and NA. However, concerning influenza B virus, when forecasting done well, the mean genetic distances between epidemic isolates and the vaccines were no higher than 0.02368 ± 0.00272; otherwise, the distances could reach 0.13695 ± 0.00238. Conclusion: When applying quadrivalent influenza vaccines (QIVs) for vaccination, the recommendations of compositions for influenza B could be altered and assessed once in 3 or 4 years; when economic burden was considered intensively and TIVs were utilized, the recommended compositions for influenza B could be announced in April or May, rather than in February or March as now.

7.
Sci Rep ; 9(1): 11641, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31406229

RESUMO

Avian influenza A viruses (AIVs) can occasionally transmit to mammals and lead to the development of human pandemic. A species of mammal is considered as a mixing vessel in the process of host adaptation. So far, pigs are considered as a plausible intermediate host for the generation of human pandemic strains, and are labelled 'mixing vessels'. In this study, through the analysis of two professional databases, the Influenza Virus Resource of NCBI and the Global Initiative on Sharing Avian Influenza Data (GISAID), we found that the species of mink (Neovison vison) can be infected by more subtypes of influenza A viruses with considerably higher α-diversity related indices. It suggested that the semiaquatic mammals (riverside mammals), rather than pigs, might be the intermediate host to spread AIVs and serve as a potential mixing vessel for the interspecies transmission among birds, mammals and human. In epidemic areas, minks, possibly some other semiaquatic mammals as well, could be an important sentinel species for influenza surveillance and early warning.

8.
J Exp Clin Cancer Res ; 37(1): 291, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30486896

RESUMO

BACKGROUND: Profound chemoresistance remains an intractable obstacle in pancreatic cancer treatment. Pancreatic cancer stem cells (CSCs) and the ubiquitous hypoxic niche have been proposed to account for drug resistance. However, the mechanism involved requires further exploration. This study investigated whether the hypoxic niche enhances gemcitabine-induced stemness and acquired resistance in pancreatic cancer cells by activating the AKT/Notch1 signaling cascade. The therapeutic effects of blockading this signaling cascade on gemcitabine-enriched CSCs were also investigated. METHODS: The expression levels of CSC-associated markers Bmi1 and Sox2 as well as those of proteins involved in AKT/Notch1 signaling were measured by Western blot analysis. The expression level of the pancreatic CSC marker CD24 was measured by flow cytometry. Change in gemcitabine sensitivity was evaluated by the MTT assay. The ability of sphere formation was tested by the sphere-forming assay in stem cell medium. The ability of migration and invasion was detected by the transwell migration/invasion assay. A mouse xenograft model of pancreatic cancer was established to determine the effect of Notch1 inhibition on the killing effect of gemcitabine in vivo. The ability of metastasis was investigated by an in vivo lung metastasis assay. RESULTS: Gemcitabine promoted pancreatic cancer cell stemness and associated malignant phenotypes such as enhanced migration, invasion, metastasis, and chemoresistance. The AKT/Notch1 signaling cascade was activated after gemcitabine treatment and mediated this process. Blockading this pathway enhanced the killing effect of gemcitabine in vivo. However, supplementation with hypoxia treatment synergistically enhanced the AKT/Notch1 signaling pathway and collaboratively promoted gemcitabine-induced stemness. CONCLUSIONS: These findings demonstrate a novel mechanism of acquired gemcitabine resistance in pancreatic cancer cells through induction of stemness, which was mediated by the activation of AKT/Notch1 signaling and synergistically aggravated by the ubiquitous hypoxic niche. Our results might provide new insights for identifying potential targets for reversing chemoresistance in patients with pancreatic cancer.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Notch1/metabolismo , Animais , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Desoxicitidina/farmacologia , Humanos , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Parasit Vectors ; 11(1): 483, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30153868

RESUMO

BACKGROUND: Human landing catch (HLC) is the most efficient method for Aedes monitoring, but it is not ethical due to its high risk of human exposure to pathogens. We designed trials to assess the performance of an alternative human-baited double net trap (HDN) for field Aedes albopictus monitoring compared with the standard HLC. METHODS: Outdoor HDN and HLC catches were conducted simultaneously at 15 field sites on two sunny days in mid-July and August. The tests were performed 3 h apart: an early morning period (7:30-8:30 h), a pre-sunset period (16:30-17:30 h) and a post-sunset period (18:30-19:30 h). A total of 90 comparisons were made between the two methods. Field comparisons were designed to minimize half-hour bias and human-bait attraction bias. RESULTS: Two mosquito species were collected by HDN and HLC, with the predominated species being Ae. albopictus (HDN: n = 1325, 97.35% of total; HLC: n = 531, 92.51% of total). A small proportion were adults of the Culex pipiens complex (HDN: n = 36, 2.65% of total; HLC: n = 43, 7.49% of total). Although the mean Ae. albopictus catch per hour of HLC was significantly higher than HDN (14.72 vs 5.90 per h, t(178) = 3.151, P = 0.003), there were significant positive spatial and temporal correlations between HLC and HDN for Ae. albopictus sampling among different sites and hours (r(90) = 0.785, P < 0.001; r(90) = 0.785, P < 0.001). Both methods proved that Ae. albopictus was most active during the hours before sunset and least active after sunset. No significant variation was observed in Ae. albopictus catch size of HDN between groups of more attractive and less attractive humans (3.38 vs 2.51 per 30 min, t(88) = 1.283, P = 0.201). CONCLUSIONS: With moderate sampling efficiency, significantly positive spatial correlation with HLC, and less human-bait attraction bias, HDN appears to be a safer alternative to HLC for Ae. albopictus monitoring in Shanghai. With mosquito activity peaking in the pre-sunset hours, Ae. albopictus catches of HDN should be performed in the hours before dark. The trap design could be improved to make it more portable and easier for field operation.


Assuntos
Aedes/fisiologia , Coleta de Dados/métodos , Controle de Mosquitos/instrumentação , Controle de Mosquitos/métodos , Animais , Anopheles/fisiologia , China , Cidades , Culex/fisiologia , Coleta de Dados/instrumentação , Entomologia/métodos , Humanos , Masculino , Odorantes
10.
J Zhejiang Univ Sci B ; 19(5): 409-414, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29732752

RESUMO

In 2013, two episodes of influenza emerged in China and caused worldwide concern. A new H7N9 avian influenza virus (AIV) first appeared in China on February 19, 2013. By August 31, 2013, the virus had spread to ten provinces and two metropolitan cities. Of 134 patients with H7N9 influenza, 45 died. From then on, epidemics emerged sporadically in China and resulted in several victims. On November 30, 2013, a 73-year-old woman presented with an influenza-like illness. She developed multiple organ failure and died 9 d after the onset of disease. A novel reassortant AIV, H10N8, was isolated from a tracheal aspirate specimen that was obtained from the patient 7 d after onset. This case was the first human case of influenza A subtype H10N8. On 4 February, 2014, another death due to H10N8 avian influenza was reported in Jiangxi Province, China.


Assuntos
Vírus da Influenza A Subtipo H9N2/classificação , Influenza Humana/virologia , Vírus Reordenados/classificação , Idoso , China/epidemiologia , Feminino , Humanos , Vírus da Influenza A Subtipo H10N8/classificação , Subtipo H7N9 do Vírus da Influenza A/classificação , Influenza Humana/epidemiologia , Filogenia
11.
Prev Vet Med ; 152: 32-39, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29559103

RESUMO

Highly pathogenic avian influenza (HPAI) H5N1 viruses have continuously circulated throughout much of the world since 2003, resulting in huge economic losses and major public health problems. Wild birds have played an important role in the spread of H5N1 HPAI. To understand its spatial distribution, H5N1 HPAI have been studied by many disciplines from different perspectives, but only one kind of disciplinary knowledge was involved, which has provided limited progress in understanding. Combining risk information from different disciplines based on knowledge fusion can provide more accurate and detailed information. In this study, local k function, phylogenetic tree analysis, and logistic spatial autoregressive models were used to explore the global spatial pattern of H5N1 HPAI based on outbreak data in wild birds, genetic sequences, and risk factors, respectively. On this basis, Dempster-Shafer (D-S) evidence theory was further applied to study the spatial distribution of H5N1 HPAI. We found D-S evidence theory was more robust and reliable than the other three methods, providing technical and methodological support for application to the research of other diseases. The shortest distance to wild bird migration routes, roads and railways, elevation, the normalized difference vegetation index (NDVI), land use and land cover (LULC) and infant mortality rates (IMR) were significantly associated with the occurrence of H5N1 HPAI. The high-risk areas were mainly located in Northern and Central Europe, the eastern Mediterranean, and East and Southeast Asia. High-risk clusters were closely related to the social, economic and ecological environment of the region. Locations where the potential transmission risk remains high should be prioritized for control efforts.


Assuntos
Aves , Surtos de Doenças/veterinária , Virus da Influenza A Subtipo H5N1/fisiologia , Influenza Aviária/epidemiologia , Animais , Animais Selvagens , Evolução Molecular , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/virologia , Modelos Teóricos , Prevalência , Fatores de Risco , Análise Espaço-Temporal
12.
PLoS One ; 12(7): e0181690, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28742883

RESUMO

Certain antibiotics detected in urine are associated with childhood obesity. In the current experimental study, we investigated two representative antibiotics detected in urine, florfenicol and azithromycin, for their early effects on adipogenesis, gut microbiota, short-chain fatty acids (SCFAs), and bile acids in mice. Thirty C57BL/6 mice aged four weeks were randomly divided into three groups (florfenicol, azithromycin and control). The two experimental groups were administered florfenicol or azithromycin at 5 mg/kg/day for four weeks. Body weight was measured weekly. The composition of the gut microbiota, body fat, SCFAs, and bile acids in colon contents were measured at the end of the experiment. The composition of the gut microbiota was determined by sequencing the bacterial 16S rRNA gene. The concentration of SCFAs and bile acids was determined using gas chromatography and liquid chromatography coupled to tandem mass spectrometry, respectively. The composition of the gut microbiota indicated that the two antibiotics altered the gut microbiota composition and decreased its richness and diversity. At the phylum level, the ratio of Firmicutes/Bacteroidetes increased significantly in the antibiotic groups. At the genus level, there were declines in Christensenella, Gordonibacter and Anaerotruncus in the florfenicol group, in Lactobacillus in the azithromycin group, and in Alistipes, Desulfovibrio, Parasutterella and Rikenella in both the antibiotic groups. The decrease in Rikenella in the azithromycin group was particularly noticeable. The concentration of SCFAs and secondary bile acids decreased in the colon, but the concentration of primary bile acids increased. These findings indicated that florfenicol and azithromycin increased adipogenesis and altered gut microbiota composition, SCFA production, and bile acid metabolism, suggesting that exposure to antibiotics might be one risk factor for childhood obesity. More studies are needed to investigate the specific mechanisms.


Assuntos
Adipogenia/efeitos dos fármacos , Antibacterianos/farmacologia , Azitromicina/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Tianfenicol/análogos & derivados , Administração Oral , Animais , Antibacterianos/administração & dosagem , Azitromicina/administração & dosagem , Peso Corporal/efeitos dos fármacos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S/genética , Tianfenicol/administração & dosagem , Tianfenicol/farmacologia
13.
Int J Parasitol ; 47(1): 21-29, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27866904

RESUMO

Schistosomiasis remains a major public health problem in eastern China, particularly along the Yangtze River Basin. The latest national schistosomiasis control program (NSCP) was implemented in 2005 with the main goal of reducing the rate of infection to less than 5% by 2008 and 1% by 2015. To assess the progress, we applied a Bayesian spatio-temporal model to describe dynamics of schistosomiasis in Guichi, Anhui Province, China, using annual parasitological and environmental data collected within 41 sample villages for the period 2005-2011. Predictive maps of schistosomiasis showed that the disease prevalence remains constant and low. Results of uncertainty analysis, in the form of probability contour maps (PCMs), indicated that the first goal of "infection rate less than 5% by 2008" was fully achieved in the study area. More longitudinal data for schistosomiasis are needed for the assessment of the second goal of "infection rate less than 1% by 2015". Compared with the traditional way of mapping uncertainty (e.g., variance or mean-square error), our PCMs provide more realistic information for schistosomiasis control.


Assuntos
Rios/parasitologia , Schistosoma/isolamento & purificação , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Animais , Teorema de Bayes , China/epidemiologia , Doenças Endêmicas , Humanos , Controle de Infecções/métodos , Dinâmica Populacional , Prevalência , Esquistossomose/sangue , Esquistossomose/parasitologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-27869687

RESUMO

BACKGROUND: Culex pipiens molestus was first reported in Shanghai in 2010. The population structures and seasonal distributions of Culex pipiens subspecies C. p. molestus, Culex pipiens pallens, and Culex pipiens quinquefasciatus are not well known. METHODS: From late February to November 2013, we conducted daily field surveillance of mosquitoes at eight sites at two green lands and three residential areas in downtown Shanghai. Morphological comparison and DV/D ratios (DV/D is an indicator of mosquito taxonomy) were used to identify adult mosquitoes. RESULTS: The distribution curves of the Culex pipiens complex members indicated seasonal fluctuations. The temperature range of 20-25 °C was the most suitable for adult activity. Micro-environmental factors may differentiate the complex population structures. Hybridization between C. p. pallens and C. p. quinquefasciatus was common and neither "DV/D = 0.40" nor "DV/D = 0.50" can distinguish these subspecies and their hybrids. Conclusion: the population structure of the Culex pipiens complex is complex and characterized by significant hybridization. Measures other than DV/D ratios are needed for the discrimination of subspecies. The C. p. molestus invasion might result in the transmission of novel vector-borne diseases in Shanghai.


Assuntos
Culex/anatomia & histologia , Culex/genética , Animais , China , Geografia , Hibridização Genética , Dinâmica Populacional , Estações do Ano
15.
BMC Infect Dis ; 16(1): 600, 2016 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-27782815

RESUMO

BACKGROUND: Novel avian influenza viruses (AIVs) of H7N9, H10N8, and H5N6 are currently circulating in China's poultry flocks, occasionally infecting human and other mammals. Human infected AIV H5N6 in China during 2014-2015 is believed to be a triple reassortant originated from H6N6 and two clades of H5 viruses. The current report suggests that its reassortment history is more complicated. METHODS: Genomes of human infected isolates of AIV H5N6 were searched from the NCBI Influenza Virus Sequence Database and the Global Initiative on Sharing Avian Influenza Data. Sequences shared high identities with each segment of their genomes were obtained through the Basic Local Alignment Search Tool. Alignments were done by mafft-7.037-win32 program; 8 large-scale and then 8 gradually converged phylogenetic trees were constructed by using MEGA5.1/5.2/6.0 Software. RESULTS: The events that each segment of the genomes of human infected AIV H5N6 isolates circulated in China had evolved into its current status might have happened before 2013, and so were they then reassorted into the epidemic AIV H5N6. A/Guangzhou/39715/2014(H5N6) and A/Sichuan/26221/2014(H5N6) had their six internal segments (PB2, PB1, PA, NP, NEP, and M) in common, and were reassorted from AIVs H5N1 in the same period and same region as that of HA, while A/Yunnan/0127/2015(H5N6) derived its six internal segments from AIV H9N2 that has been prevalent in Eastern China since 2008. CONCLUSIONS: AIV H5N6 isolates established from both human and poultry in China during 2014-2015 were heterogeneous; both AIVs H5N1 and H9N2 were involved in the reassortment of AIV H5N6 in China.


Assuntos
Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Animais , China , Humanos , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/virologia , Influenza Humana/virologia , Filogenia , Aves Domésticas
16.
Sci Rep ; 6: 24173, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27053447

RESUMO

Schistosomiasis remains a major public health problem and causes substantial economic impact in east China, particularly along the Yangtze River Basin. Disease forecasting and surveillance can assist in the development and implementation of more effective intervention measures to control disease. In this study, we applied a Bayesian hierarchical spatio-temporal model to describe trends in schistosomiasis risk in Anhui Province, China, using annual parasitological and environmental data for the period 1997-2010. A computationally efficient approach-Integrated Nested Laplace Approximation-was used for model inference. A zero-inflated, negative binomial model best described the spatio-temporal dynamics of schistosomiasis risk. It predicted that the disease risk would generally be low and stable except for some specific, local areas during the period 2011-2014. High-risk counties were identified in the forecasting maps: three in which the risk remained high, and two in which risk would become high. The results indicated that schistosomiasis risk has been reduced to consistently low levels throughout much of this region of China; however, some counties were identified in which progress in schistosomiasis control was less than satisfactory. Whilst maintaining overall control, specific interventions in the future should focus on these refractive counties as part of a strategy to eliminate schistosomiasis from this region.


Assuntos
Teorema de Bayes , Vigilância da População/métodos , Schistosoma japonicum/fisiologia , Esquistossomose Japônica/parasitologia , Animais , Grupo com Ancestrais do Continente Asiático/estatística & dados numéricos , China/epidemiologia , Biologia Computacional/métodos , Doenças Endêmicas , Geografia Médica , Interações Hospedeiro-Parasita , Humanos , Modelos Teóricos , Prevalência , Fatores de Risco , Esquistossomose Japônica/epidemiologia , Esquistossomose Japônica/etnologia , Análise Espaço-Temporal
17.
Int J Infect Dis ; 43: 85-89, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26778522

RESUMO

BACKGROUND: A novel avian influenza A H7N9 virus that infects humans was identified in China in 2013. This study is the first to comprehensively investigate the characteristics of genomic recombination, rather than reassortment, which has been the subject of investigation in previously reported studies. METHODS: Novel avian influenza virus (AIV) H7N9 genome sequences were obtained from the NCBI Influenza Virus Sequence Database and the Global Initiative on Sharing Avian Influenza Database (GISAID) and a representative isolate was subjected to homogeneity analysis. A phylogenetic tree was constructed. Eight segments of the isolate were analyzed to identify segments with recombination events, the corresponding recombination fragments, and breakpoints. The evolutionary history of the recombined fragments was tracked by constructing phylogenetic trees of the recombination fragments. RESULTS: Among the eight segments of the novel AIV H7N9 analyzed, only the PB1 segment showed a marked recombination phenomenon, with 11 recombination events; these included five actual recombination events and six possible misalignment artifact recombination events. The most notable was the recombination of a 291-nucleotide (nt) fragment at the 490-780 nt site that was affiliated to a highly pathogenic avian influenza virus (HPAIV) H5N1 (A/tree sparrow/Thailand/VSMU-16-RBR/2005). The phylogenetic tree of the 291-nt recombination fragment on the PB1 segment showed that the novel AIV H7N9 had a close genetic relationship to H9N2 and H5N1. CONCLUSIONS: The novel AIV H7N9 might have reassorted its PB1 segment from H9N2 circulating in China, and this H9N2 PB1 might have been recombined into a highly pathogenic fragment from HPAIV H5N1, which could be the reason for the high fatality rate among patients with AIV H7N9 influenza.


Assuntos
Genoma Viral/genética , Virus da Influenza A Subtipo H5N1/genética , Subtipo H7N9 do Vírus da Influenza A/genética , Vírus da Influenza A Subtipo H9N2/genética , Influenza Humana/virologia , Proteínas Virais/genética , Animais , Evolução Biológica , China/epidemiologia , Epidemias , Humanos , Virus da Influenza A Subtipo H5N1/patogenicidade , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Vírus da Influenza A Subtipo H9N2/patogenicidade , Influenza Humana/epidemiologia , Filogenia , Recombinação Genética , Virulência
18.
Geospat Health ; 10(2): 374, 2015 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-26618320

RESUMO

Helminth infections are believed to be common in tropical and subtropical countries. A cross-sectional study was carried out in two villages located in Guichi District in Anhui Province, the People's Republic of China, where multiparasitism was investigated using parasitological tests. The data collected were fitted to Bayesian multi-level models to profile risk factors for helminth infections. The prevalence of Schistosoma (S.) japonicum, Ascaris (A.) lumbricoides and Trichuris (T.) trichiura were 0.43% (range: 0-0.87% at the village level), 2.28% (range: 1.69-2.88%), and 0.21% (range: 0-0.42%), respectively. No hookworm infection was found. With regard to multiparasitism, only a 33-year-old female was found to be co-infected with S. japonicum and A. lumbricoides. Multiparasitism was unexpectedly rare in the study area, which contrasts with results from other studies carried out elsewhere in the country. The long-term usage of albendazole for individuals serologically positive for schistosomiasis may be the main reason, but this needs to be confirmed by future studies.


Assuntos
Helmintíase/epidemiologia , Helmintíase/parasitologia , Adolescente , Adulto , Idoso , Teorema de Bayes , Criança , Pré-Escolar , China/epidemiologia , Coinfecção/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , População Rural
19.
Geospat Health ; 10(1): 324, 2015 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-26054518

RESUMO

Schistosomiasis mapping using data obtained from parasitological surveys is frequently used in planning and evaluation of disease control strategies. The available geostatistical approaches are, however, subject to the assumption of stationarity, a stochastic process whose joint probability distribution does not change when shifted in time. As this is impractical for large areas, we introduce here the sandwich method, the basic idea of which is to divide the study area (with its attributes) into homogeneous subareas and estimate the values for the reporting units using spatial stratified sampling. The sandwich method was applied to map the county-level prevalence of schistosomiasis japonica in Anhui Province, China based on parasitological data collected from sample villages and land use data. We first mapped the county-level prevalence using the sandwich method, then compared our findings with block Kriging. The sandwich estimates ranged from 0.17 to 0.21% with a lower level of uncertainty, while the Kriging estimates varied from 0 to 0.97% with a higher level of uncertainty, indicating that the former is more smoothed and stable compared to latter. Aside from various forms of reporting units, the sandwich method has the particular merit of simple model assumption coupled with full utilization of sample data. It performs well when a disease presents stratified heterogeneity over space.


Assuntos
Vigilância da População/métodos , Esquistossomose/epidemiologia , Análise Espacial , China/epidemiologia , Humanos , Modelos Estatísticos , Prevalência
20.
Int J Environ Res Public Health ; 12(1): 1020-8, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25608590

RESUMO

UNLABELLED: Objective. A novel avian influenza A virus (AIV) H7N9 subtype which emerged in China in 2013 caused worldwide concern. Deletion of amino-acids 69 to 73 in the neuraminidase stalk was its most notable characteristic. This study is aimed to discuss the tropism and virulence effects of this deletion. METHODS: Neuraminidase gene sequences of N9 subtype were collected from NCBI and GISAID. MEGA6.0, Stata12.0, and UCSF Chimera were employed for sequence aligning, significance testing, and protein tertiary structure homology modeling. RESULTS: A total of 736 sequences were obtained; there were 81 human isolates of the novel AIV H7N9, of which 79 had the deletion. Among all the 654 avian origin sequences, only 43 had the deletion (p < 0.001). Tertiary structure displayed that the deletion obviously changed the spatial direction of neuraminidase. CONCLUSIONS: The deletion in neuraminidase stalk could have strengthened human tropism of the novel AIV H7N9, as well as its virulence.


Assuntos
Sequência de Bases , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Neuraminidase/genética , Deleção de Sequência , Proteínas Virais/genética , China , Humanos , Subtipo H7N9 do Vírus da Influenza A/genética , Influenza Humana/virologia , Neuraminidase/química , Neuraminidase/metabolismo , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência , Proteínas Virais/química , Proteínas Virais/metabolismo , Tropismo Viral
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