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1.
Cell Mol Biol (Noisy-le-grand) ; 70(1): 34-39, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38372115

RESUMEN

Acute lung injury (ALI) is associated with the leukocyte infiltration and inflammation. Previous studies have shown that miR-146a is a valid regulator of the macrophage polarization in vitro inflammatory model. However, it is unclear whether miR-146a plays a protective role in ALI via modulating macrophage inflammation. To explore the potential therapeutic effect mechanism of miR-146a on ALI. We analyzed the expression of miR-146a in acute injured lung tissues and differentiated macrophage. Lipopolysaccharide (LPS) and interleukin-4 (IL-4) were employed in provoking the macrophage to polarization. We used miR-146a mimics to improve the overexpression of miR-146a and investigated the effect of increased miR-146a on LPS-induced ALI mice via the target of macrophage polarization. We showed that the expression of miR-146a markedly decreased in injured lung tissue and type M1 macrophage, while increased miR-146a expression exhibited in type M2 macrophage. Moreover, overexpression of miR-146a in LPS-induced macrophage reversed inflammatory M1 phenotype to anti-inflammatory M2 phenotype and mitigated inflammatory level via inhibiting Notch 1 signaling pathway. Hence, inflammation, infiltration, integrity of capillary barrier, and histology in ALI model were corrected after miR-146a overexpression treatment. These results suggested that miR-146a promotes type M2 macrophage polarization via restraining Notch 1 signaling pathway. Overexpression of miR-146a prevents inflammation damage and ameliorates lung damage after LPS induction. Therefore, miR-146a may serve as a promising target for the therapy of ALI in the future.


Asunto(s)
Lesión Pulmonar Aguda , MicroARNs , Receptor Notch1 , Transducción de Señal , Animales , Ratones , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/genética , Inflamación/metabolismo , Lipopolisacáridos/toxicidad , Macrófagos/metabolismo , MicroARNs/metabolismo , Receptor Notch1/metabolismo
2.
Comput Intell Neurosci ; 2021: 8128879, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34621309

RESUMEN

Stock price prediction is very important in financial decision-making, and it is also the most difficult part of economic forecasting. The factors affecting stock prices are complex and changeable, and stock price fluctuations have a certain degree of randomness. If we can accurately predict stock prices, regulatory authorities can conduct reasonable supervision of the stock market and provide investors with valuable investment decision-making information. As we know, the LSTM (Long Short-Term Memory) algorithm is mainly used in large-scale data mining competitions, but it has not yet been used to predict the stock market. Therefore, this article uses this algorithm to predict the closing price of stocks. As an emerging research field, LSTM is superior to traditional time-series models and machine learning models and is suitable for stock market analysis and forecasting. However, the general LSTM model has some shortcomings, so this paper designs a LightGBM-optimized LSTM to realize short-term stock price forecasting. In order to verify its effectiveness compared with other deep network models such as RNN (Recurrent Neural Network) and GRU (Gated Recurrent Unit), the LightGBM-LSTM, RNN, and GRU are respectively used to predict the Shanghai and Shenzhen 300 indexes. Experimental results show that the LightGBM-LSTM has the highest prediction accuracy and the best ability to track stock index price trends, and its effect is better than the GRU and RNN algorithms.


Asunto(s)
Inversiones en Salud , Redes Neurales de la Computación , Algoritmos , China , Predicción
3.
Cancer Biomark ; 24(3): 279-289, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30883341

RESUMEN

Multiple myeloma (MM) is a common hematological malignancy that is often associated with osteolytic lesions, anemia and renal impairment. Deregulation of miRNA has been implicated in the pathogenesis of MM. It was found in our study that miR-19b and miR-20a as members of crucial oncogene miR-17-92 cluster were differentially expressed between patients with MM and normal controls by genechip microarray, and this result was further confirmed in sera of patients with MM by qRT-PCR. The functional effect of miR-19b/20a was analyzed and results showed that miR-19b/20a promoted cell proliferation and migration, inhibited cell apoptosis and altered cell cycle in MM cells. PTEN protein expression was reduced after transfection of miR-19b/20a, suggesting that PTEN was a direct target of miR-19b/20a. In addition, over-expression of miR-19b/20a reversed the anti-proliferation and pro-apoptosis effect of PTEN in MM cells. Finally, our in vivo experiment demonstrated that lentivirus-mediated delivery of miR-20a promoted tumor growth in murine xenograft model of MM, which provide evidence that miR-20a inhibitor exerts therapeutic activity in preclinical models and supports a framework for the development of miR-19b/20a-based treatment strategies for MM patients.


Asunto(s)
Apoptosis/genética , Transformación Celular Neoplásica/genética , MicroARNs/genética , Mieloma Múltiple/genética , Fosfohidrolasa PTEN/genética , Anciano , Anciano de 80 o más Años , Animales , Biomarcadores de Tumor , Estudios de Casos y Controles , Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular/genética , Biología Computacional/métodos , Modelos Animales de Enfermedad , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genes Reporteros , Xenoinjertos , Humanos , Masculino , Ratones , Persona de Mediana Edad , Interferencia de ARN
4.
Front Microbiol ; 9: 2771, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30524397

RESUMEN

Hemorrhagic fever with renal syndrome (HFRS) is a serious public health problem in Shandong Province, China. We conducted an epizootiologic investigation and phylogeographic and phylodynamic analyses to infer the phylogenetic relationships of hantaviruses in space and time, and gain further insights into their evolutionary dynamics in Shandong Province. Our data indicated that the Seoul virus (SEOV) is distributed throughout Shandong, whereas Hantaan virus (HTNV) co-circulates with SEOV in the eastern and southern areas of Shandong. Their distribution showed strong geographic clustering. In addition, our analyses indicated multiple evolutionary paths, long-distance transmission, and demographic expansion events for SEOV in some areas. Selection pressure analyses revealed that negative selection on hantaviruses acted as the principal evolutionary force, whereas a little evidence of positive selection exists. We found that several positively selected sites were located within major functional regions and indicated the importance of these residues for adaptive evolution of hantaviruses.

5.
Arch Virol ; 163(10): 2899-2902, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29872952

RESUMEN

Two double-stranded RNA viruses, named Culex tritaeniorhynchus totivirus NJ2 (CTV_NJ2) and NJ3 (CTV_NJ3), were discovered from wild-captured Culex tritaeniorhynchus mosquitoes. The complete genomes (7,624 and 7,612 bp in length) were obtained using RNA sequencing. Both CTV_NJ2 and CTV_NJ3 encode a putative capsid protein and an RNA-dependent RNA polymerase. The most similar strain to CTV_NJ2/3 is Omono River virus strain AK4 (ORV-AK4). The CP and RdRp identities of AK4 are different to CTV_NJ2 (84% and 87%) and CTV_NJ3 (47% and 62%). Phylogenetic analysis showed that taxonomically speaking CTV_NJ2/3 grouped within the unclassified Totiviridae and formed a distinct clade with other arthropod-infecting viruses.


Asunto(s)
Culex/virología , Genoma Viral/genética , Totiviridae , Animales , Proteínas de la Cápside/genética , Filogenia , ARN Viral/genética , ARN Polimerasa Dependiente del ARN/genética , Totiviridae/clasificación , Totiviridae/genética , Totiviridae/aislamiento & purificación
6.
Vector Borne Zoonotic Dis ; 17(12): 804-812, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29083983

RESUMEN

During 2007 and 2010, an extensive entomological survey was performed to assess the distribution of mosquitoes and mosquito-borne arboviruses at Lancang River and Nu River watersheds in southwestern China. A total of 20,450 mosquitoes consisting 20 species was trapped and submitted 261 pools according to species and location. Culex tritaeniorhynchus and Anopheles sinensis were the most abundant species. Eighty-seven isolates representing 11 virus species in 8 genera were obtained from 6 mosquito species. The new isolates were identified as Getah virus (GETV), Japanese encephalitis virus (JEV), Yunnan Culex-related flavivirus (YNCxFV), Yunnan Aedes-related flavivirus (YNAeFV), Banna virus (BAV), Yunnan orbivirus (YUOV), Banna orbivirus (BAOV), Yunnan totivirus (YNToV), Nam Dinh virus (NDiV), Menghai rhabdovirus (MRV), and Anopheles minimus iridovirus (AMIV). These viruses included confirmed or potential pathogen of human disease, such as JEV, BAV, and NDiV, and several novel or reassortant arboviruses, such as YNAeFV, MRV, AMIV, and BAOV. GETV, JEV, YNCxFV, and NDiV were widely prevalent in the whole basin of the two rivers. The findings contribute to our understanding of the diversity and wide distribution of mosquito-borne arboviruses in the area, and are helpful to explore pathogenic evidence for fevers and viral encephalitis of unknown etiology.


Asunto(s)
Anopheles/virología , Culex/virología , Mosquitos Vectores , Ríos , Virosis/epidemiología , Virus/aislamiento & purificación , Animales , China , Humanos , ARN Viral , Virosis/transmisión , Virus/clasificación
7.
Arch Virol ; 162(5): 1435-1439, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28175982

RESUMEN

Menghai flavivirus (MFV) was isolated from Aedes albopictus in Menghai county of Yunnan Province, China, during an arboviruses screening program in August 2010. Whole genome sequencing of MFV was performed using an Ion PGM™ Sequencer. The complete genome of MFV was 10897 nucleotides in length and encoded a polyprotein and fairly interesting flavivirus orf (FIFO). The polyprotein contained three flavivirus structural proteins (C, prM/M and E) and seven nonstructural proteins. Nucleotide BLAST analysis revealed that the MFV genome showed highest similarity to Xishuangbanna Aedes flavivirus, a novel insect-specific flavivirus recently isolated from the same area. These species shared a query cover of 99%, but only 71% identity, while FIFO showed no similarity with any of the published sequences. Genomic and phylogenetic analyses suggested that MFV was a novel species of the genus Flavivirus. Our findings enrich our understanding of the genetics and prevalence of the family Flaviviridae.


Asunto(s)
Aedes/virología , Proteínas de la Cápside/genética , Flavivirus/clasificación , Flavivirus/genética , Genoma Viral/genética , ARN Viral/genética , Proteínas no Estructurales Virales/genética , Animales , Composición de Base/genética , Secuencia de Bases , China , Flavivirus/aislamiento & purificación , Filogenia , Análisis de Secuencia de ADN
9.
Arch Virol ; 162(4): 1103-1106, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28000049

RESUMEN

Menghai rhabdovirus (MRV) was isolated from Aedes albopictus in Menghai county of Yunnan Province, China, in August 2010. Whole-genome sequencing of MRV was performed using an Ion PGM™ Sequencer. We found that MRV is a single-stranded, negative-sense RNA virus. The complete genome of MRV has 10,744 nt, with short inverted repeat termini, encoding five typical rhabdovirus proteins (N, P, M, G, and L) and an additional small hypothetical protein. Nucleotide BLAST analysis using the BLASTn method showed that the genome sequence most similar to that of MRV is that of Arboretum virus (NC_025393.1), with a Max score of 322, query coverage of 14%, and 66% identity. Genomic and phylogenetic analyses both demonstrated that MRV should be considered a member of a novel species of the family Rhabdoviridae.


Asunto(s)
Aedes/virología , Genoma Viral , Rhabdoviridae/genética , Rhabdoviridae/aislamiento & purificación , Aedes/genética , Animales , China , Datos de Secuencia Molecular , Filogenia , ARN Viral , Rhabdoviridae/clasificación , Análisis de Secuencia de ADN , Proteínas Virales/genética
10.
Arch Virol ; 161(6): 1723-7, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27001304

RESUMEN

A new flavivirus, Xishuangbanna flavivirus (XFV), infecting Aedes albopictus mosquitoes in Yunnan Province, China, was isolated and sequenced. The single-stranded RNA genome of 10,884 nt contained two open reading frames (ORFs) encoding the polyprotein and FIFO. The genome had a maximum nucleotide sequence identity of 65 % to Parramatta River virus with coverage of only 27 %. Phylogenetic analysis suggested that this virus is most closely related to recognized classical insect-specific flaviviruses (cISF) and most likely has a similar host range. Sequence comparisons and phylogenetic analysis demonstrated that XFV is a new member of the genus Flavivirus.


Asunto(s)
Aedes/virología , Flavivirus/genética , Animales , China , Flavivirus/clasificación , Flavivirus/aislamiento & purificación , Genoma Viral , Filogenia , ARN Viral/genética , Proteínas Virales/genética
11.
J Invertebr Pathol ; 127: 1-5, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25637833

RESUMEN

An invertebrate iridovirus (designated AMIV) was isolated from adult wild-captured Anopheles minimus mosquitoes in China. AMIV was pathologically and morphologically characterized and sequenced using the Ion Torrent™ sequencing platform. Phylogenetic analysis based on both the major capsid protein and core genes revealed that AMIV differs from all the members of the family Iridoviridae. The AMIV negatively strained virion has a diameter of about 130nm. AMIV contains a linear DNA molecule of 163,023bp, with 39% G+C content and 148 coding sequences. The genome analysis revealed that AMIV genome encodes a high content of replication associated genes including BRO-like genes. This is the ninth complete genome of IIV reported.


Asunto(s)
Anopheles/virología , Iridovirus/fisiología , Animales , Secuencia de Bases , China , ADN Viral , Genoma Viral , Filogenia , Análisis de Secuencia de ADN
12.
Virus Res ; 184: 82-6, 2014 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-24553099

RESUMEN

Inspired by the recent discovery of genetically distinct hantaviruses from insectivore species worldwide, we performed a small-scale search for insectivore-borne hantaviruses. In this paper, we report the discovery of a new hantavirus, which was designated the Qian Hu Shan virus (QHSV). This virus was detected in the lung tissues of three stripe-backed shrews (Sorex cylindricauda), which were captured in the Yunnan Province, China. The full-length S genomic segment of the representative QHSV strain YN05-284 was 1661 nucleotides and is predicted to encode a nucleocapsid protein of 429 amino acids that starts at nucleotide position 48. It exhibited the highest similarity with other Sorex-related hantaviruses, with 68.1%-72.8% nucleotide and 71.9%-84.4% amino acid sequence identities. An analysis of a 1430-nucleotide region of the partial M segment exhibited approximately 54.4%-79.5% nucleotide and 43.2%-90.8% amino acid sequence identities to other hantaviruses. A comparison of a 432-nucleotide region of the L segment also showed similar degrees of identity, with 68.9%-78.4% nucleotide and 71.1%-93.8% amino acid sequence identities to other hantaviruses. Phylogenetic analyses using Bayesian methods indicated that QHSV shared the most recent common ancestor with other Sorex-related hantaviruses. The host was identified using a morphological assessment and verified using mitochondrial cytochrome b (mt-Cyt b) gene sequencing. A pair-wise comparison of the 1140-nucleotide mt-Cyt b gene sequence from the host demonstrated that the host was close to S. cylindricauda from Nepal with 94.3% identity. The virus-host association tanglegram, which was constructed using the Dendroscope software, indicated that the QHSV phylogeny and the host phylogeny were approximately matched, which suggests no evidence of host switching for QHSV. Our results contribute to a wider viewpoint regarding the heterogeneity of viruses that infect shrews.


Asunto(s)
Eulipotyphla/virología , Infecciones por Hantavirus/veterinaria , Orthohantavirus/clasificación , Orthohantavirus/aislamiento & purificación , Musarañas/virología , Animales , China , Análisis por Conglomerados , Eulipotyphla/clasificación , Eulipotyphla/genética , Orthohantavirus/genética , Infecciones por Hantavirus/virología , Pulmón/virología , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Análisis de Secuencia de ADN , Homología de Secuencia , Musarañas/clasificación , Musarañas/genética
13.
Virus Res ; 180: 31-8, 2014 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-24342141

RESUMEN

Flaviviruses present a wide range of genetic diversity and exhibit diverse host relationships. Mosquito-borne flaviviruses have recently been isolated and characterized worldwide. Yunnan Province of China is one of the richest areas of species diversity and is the center of multi-species evolution in mainland Asia, which supports the circulation of numerous arthropod-borne viruses (arboviruses). In a screening program of arboviruses, mosquitoes were collected during the mosquito activity season in the Yunnan Province from 2007 to 2010. Eleven flavivirus strains, named Yunnan Culex flaviviruses (YNCxFVs), were obtained from Culex tritaeniorhynchus and Anopheles sinensis specimens. Sequence analyses based on partial nonstructural protein (NS) 5 gene indicated that the YNCxFVs shared 92.8-99.6% nucleotide identity with each other and were similar to the Culex-related flaviviruses. The complete genome of one representative isolate, LSFlaviV-A20-09, was sequenced. The genome was 10,865 nucleotides long and contained a single, long open reading frame (ORF) of 10,080 nucleotides that encoded a 3360-aa polyprotein. This genome was most closely related to the Quang Binh virus (QBV) VN180 strain, an insect-specific flavivirus isolated from Culex mosquitoes in Vietnam, but only had 83.0% nucleotide and 93.8% amino acid identities for the ORF sequence. The genome has approximately 66.3%-68.5% nucleotide sequence and 69.3-73.3% amino acid sequence identities to other Culex flaviviruses, and only has 47.9-57.9% nucleotide sequence and 38.7-55.1% amino acid sequence identities to Coquillettidia-related, Mansonia-related and Aedes-related flaviviruses. Phylogenetic analyses revealed that the LSFlaviV-A20-09 fell into the Culex-related flavivirus clade. Our discoveries provide more information regarding the heterogeneity of viruses that infect mosquitoes.


Asunto(s)
Anopheles/virología , Culex/virología , Flavivirus/clasificación , Flavivirus/aislamiento & purificación , Animales , China , Análisis por Conglomerados , Genoma Viral , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia , Poliproteínas/genética , ARN Viral/genética , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Proteínas Virales/genética
14.
Virol J ; 10: 70, 2013 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-23497045

RESUMEN

BACKGROUND: Epidemic dengue activity has been demonstrated in several southern regions of China, but not in Yunnan province, which borders countries in Southeast Asia where dengue is endemic. Many dengue cases imported from Southeast Asia to Yunnan have been reported, but dengue virus (DENV) has not been isolated from any patients. This study is the first to report the isolation of DENV from a Chinese traveler returning to Yunnan from Lao PDR. FINDINGS: A serum sample was collected from a patient presenting with a febrile illness who returned from Lao PDR in 2009 and was used to inoculate Aedes albopictus C6/36 cells for viral isolation. The viral isolate was identified using reverse transcription-polymerase chain reaction, and phylogenetic analyses based on the full E sequence were performed using Clustalx 1.8 software. The analyses detected DENV genome, and thus, a DENV isolate was obtained from the patient's serum sample. The new DENV isolate was grouped into genotype Asia 1, serotype 2. The viral E protein shared the greatest nucleotide sequence identity (99.6%) with the D2/Thailand/0606aTw strain isolated from Thailand in 2006 and demonstrated 94.3% to 100% identity with the predicted amino acid sequence of other DENV 2 strains. CONCLUSIONS: Our findings indicate that DENV serotype 2 is circulating in Lao PDR, and surveillance of patients suspected of infection with dengue should be conducted not only by a serological test but also by pathogenic detection methods.


Asunto(s)
Virus del Dengue/aislamiento & purificación , Dengue/virología , Adulto , Aedes , Animales , China/epidemiología , Dengue/epidemiología , Dengue/transmisión , Virus del Dengue/clasificación , Virus del Dengue/genética , Humanos , Laos/epidemiología , Masculino , Datos de Secuencia Molecular , Filogenia , Viaje , Adulto Joven
15.
Int J Infect Dis ; 16(4): e285-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22325034

RESUMEN

OBJECTIVES: The SA14-14-2 Japanese encephalitis (JE) live attenuated vaccine is licensed for use only in China, and has provided excellent efficacy in reducing the incidence of JE. The humoral immune response related to the JE vaccination has been well characterized, however cellular immune responses are less well known. METHODS: Thirty-four healthy males who had recently received inoculation with the SA14-14-2 live attenuated vaccine were recruited. Serum samples from these subjects were analyzed for cytokine and chemokine levels using the FlowCytomix method. RESULTS: Eighteen of 34 subjects were positive for JE virus-specific IgG antibodies. Levels of interleukin (IL)-8, monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1α, and MIP-1ß were significantly higher in the vaccinees than in a control group (p<0.0001, p<0.0001, p=0.021, and p<0.0001, respectively). IL-6 was detectable in 64.7% of vaccinees, but was not detectable in any of the controls. IL-1ß, IL-2, IL-4, IL-5, IL-9, IL-10, IL-12p70, IL-13, IL-17A, IL-22, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ were detected in very few subjects or were undetectable in both groups. CONCLUSIONS: IL-6, IL-8, MCP-1, MIP-1α, and MIP-1ß may play important roles in the immune response to JE live attenuated vaccine.


Asunto(s)
Quimiocinas/sangre , Interleucina-6/sangre , Vacunas contra la Encefalitis Japonesa/inmunología , Vacunas Atenuadas/inmunología , Adulto , Anticuerpos Antivirales/sangre , Quimiocinas/metabolismo , Humanos , Interleucina-6/metabolismo , Masculino , Adulto Joven
16.
BMC Infect Dis ; 11: 344, 2011 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-22168358

RESUMEN

BACKGROUND: Japanese encephalitis (JE) vaccination is the most effective measure for preventing JE disease. The live attenuated JE vaccine, which has shown good efficacy and safety, has been widely used in China. CASE PRESENTATIONS: We report four laboratory-confirmed JE cases detected in JE-endemic areas during the JE virus (JEV) transmission season, who all received a first dose of live attenuated JE vaccine within 2 weeks prior to the onset of illness. All cases presented with acute encephalitis and rapidly reduced consciousness. All cerebrospinal fluid (CSF) samples from the patients were positive for JEV-specific immunoglobulin M (IgM) antibodies, but viral isolation and polymerase chain reaction (PCR) detection of JEV were both negative. CONCLUSIONS: It is difficult to identify a causal link between the disease and the vaccination, as the source of positive CSF JEV IgM antibodies might be natural JEV infection or possibly due to a traumatic lumbar puncture. Our observations highlight the need for public health officers and doctors to consider reasonable vaccination policies during the JE season. In addition, continued surveillance as well as thorough investigation of any events that occur after JE vaccination is necessary.


Asunto(s)
Encefalitis Japonesa/etiología , Vacunas contra la Encefalitis Japonesa/efectos adversos , Anticuerpos Antivirales/líquido cefalorraquídeo , Preescolar , China , Virus de la Encefalitis Japonesa (Especie)/aislamiento & purificación , Encefalitis Japonesa/líquido cefalorraquídeo , Encefalitis Japonesa/inmunología , Femenino , Humanos , Inmunoglobulina M/líquido cefalorraquídeo , Lactante , Masculino , Factores de Tiempo
17.
PLoS One ; 6(1): e16418, 2011 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-21283590

RESUMEN

BACKGROUND: Several studies have shown that the predominant genotype of Chinese Japanese encephalitis virus (JEV) is evolving from genotype 3 to genotype 1. However, in recent years, almost all genotype 1 isolates were from mosquitoes, and genotype 1 has been less associated with human disease than genotype 3. This study reports the isolation of human genotype 1 JEV and its genetic characteristics to provide additional insights into human JE pathogens that are currently circulating in China. METHODS AND RESULTS: In 2009, 31 cerebrospinal fluid samples were collected from patients living in Yunnan and Shanxi provinces and were used to inoculate Aedes albopictus C6/36 cells for virus isolation. The JEV strains were identified using immunofluorescent assays and the reverse transcription-polymerase chain reaction. Phylogenetic analyses based on the partial capsid/pre-membrane and full envelope (E) sequences were performed using Clustalx 1.8 software. Three JEV isolates were obtained from a 4-year-old girl and a 2-year-old boy living in Yunnan and an 82-year-old woman in Shanxi. The boy had been immunized with one dose of JE live attenuated vaccine. New isolates were grouped into genotype 1. Amino acid sequence for the viral E protein indicated 95% to 100% identity with each other and with other JEV strains. When compared with a consensus sequence of E protein, two amino acid substitutions were found: Ser(E-123)-Asn in the two Yunnan isolates and Lys(E-166)-Arg in the Shanxi isolate. CONCLUSIONS: Our findings indicate that the genotype 1 of JEV is causing human infections in China. Our observation of a previously vaccinated boy developing JE from genotype 1 virus infection also calls for more detailed studies, both in vitro and in vivo neutralization tests as well as active surveillance, to examine the possibility of a lack of complete protection conferred by the live attenuated JE vaccine against genotype 1 virus.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie)/aislamiento & purificación , Anciano de 80 o más Años , Secuencia de Aminoácidos , Niño , Preescolar , China , Virus de la Encefalitis Japonesa (Especie)/genética , Encefalitis Japonesa/virología , Femenino , Genotipo , Humanos , Masculino , Filogenia , Vacunas Atenuadas/farmacología , Proteínas Virales/genética
18.
Virus Res ; 153(1): 157-60, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20600393

RESUMEN

Hantavirus genome sequences were recovered from lung tissues of Chinese white-bellied rats (Niviventer confucianus) captured in Yunnan province, China. Pairwise comparison of the nucleotide and deduced amino acid sequences of the entire S and partial M and L segments indicated that the newly discovered virus strain, which was designated as strain YN509, was very different from other rodent-borne hantaviruses. Phylogenetic analysis showed that the new strain fit into a clade containing Da Bie Shan virus (DBSV) (also carried by N. confucianus), which is mainly found in Anhui Province in mainland China. Strain YN509 appears to be in a sister taxa of the DBSV group described previously. These data suggest that strain YN509 is a new subtype of DBSV, which appears to be widely distributed in China with a higher genetic diversity than expected.


Asunto(s)
Infecciones por Hantavirus/veterinaria , Murinae/virología , Orthohantavirus/genética , Enfermedades de los Roedores/virología , Animales , China , Análisis por Conglomerados , Orthohantavirus/aislamiento & purificación , Infecciones por Hantavirus/virología , Pulmón/virología , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Ratas , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Proteínas Virales/genética
19.
Arch Virol ; 154(7): 1177-80, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19543849

RESUMEN

We determined the complete nucleotide sequence of a Japanese encephalitis virus (JEV) isolate (designated SH17M-2007) from a pool of Culex tritaeniorhynchus collected in southern China in 2007. The genome consisted of 10,965 nucleotides and included a single open reading frame (10,296 nucleotides) that encodes a 3,432-amino-acid polyprotein. The SH17M-2007 had 97.3 to 98.4% nucleotide identity with two Korean strains (KV1899, K94P05) and two Japanese strains (Ishikawa, JEV/sw/Mie/40/2004), but only 88.8% identity with the Chinese vaccine strain SA14-14-2. Five unique amino acid substitutions including one in the envelope (E) protein (Glu(E-306)-Lys) were found in the SH17M-2007 strain. Phylogenetic relationships based on the full-length nucleotide sequences were similar to those based on the E gene.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie)/genética , Genoma Viral , Animales , Secuencia de Bases , China , Culex/virología , Virus de la Encefalitis Japonesa (Especie)/clasificación , Virus de la Encefalitis Japonesa (Especie)/aislamiento & purificación , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia
20.
BMC Microbiol ; 8: 152, 2008 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-18798995

RESUMEN

BACKGROUND: Tularemia was reported in China over 50 years ago, however, many epidemical characteristics remain unclear. In the present study, the prevalence of Francisella tularensis in ticks was investigated during an epidemiological surveillance in China and then we measured their genetic diversity by conducting multiple-locus variable- number tandem repeat analysis (MLVA). RESULTS: 1670 ticks from 2 endemic areas (Inner Mongolia Autonomous Region and Heilongjiang Province) and 2 non-endemic areas (Jilin and Fujian Provinces) were collected and tested for evidence of tularemia by nested PCR. The prevalence of Francisella tularensis in ticks averaged 1.98%. The positive rates were significantly different among tick species, with Dermacentor silvarum and Ixodes persulatus responsible for all positive numbers. All F. tularensis that were detected in ticks belonged to F. tularensis subsp. holarctica and MLVA disclosed genetic diversity. One subtype was identified in 17 of 33 positive tick samples in three different study areas. Another subtype belonging to F. tularensis subsp. holarctica genotype was described for the first time in the current study. CONCLUSION: The study showed two tick species, D. silvarum and I. persulatus harboring the pathogen of tularemia in natural environment, indicating these two tick species might have a role in tularemia existence in China. MLVA results disclosed the genetic diversity F. tularensis and identified one genotype as the most prevalent among the investigated ticks in China.


Asunto(s)
Dermacentor/microbiología , Francisella tularensis/genética , Genotipo , Ixodes/microbiología , Repeticiones de Minisatélite , Animales , Vectores Arácnidos/microbiología , Técnicas de Tipificación Bacteriana , China/epidemiología , ADN Bacteriano/genética , Reservorios de Enfermedades/microbiología , Francisella tularensis/clasificación , Variación Genética , Epidemiología Molecular , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Prevalencia , Tularemia/epidemiología , Tularemia/genética
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