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1.
BMC Infect Dis ; 24(1): 585, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38867171

RESUMEN

BACKGROUND: We investigated the presence of Chlamydia psittaci in poultry and the environment in live poultry wholesale markets in Changsha during 2021-2022 and conducted a phylogenetic analysis to understand its distribution in this market. METHODS: In total, 483 samples were analyzed using real-time polymerase chain reaction and 17 C. psittaci-positive samples using high-throughput sequencing, BLAST similarity, and phylogenetic analysis. RESULTS: Twenty-two out of 483 poultry and environmental samples were positive for C. psittaci (overall positivity rate: 4.55%) with no difference in positivity rates over 12 months. Chlamydia psittaci was detected at 11 sampling points (overall positivity rate: 27.5%), including chicken, duck, and pigeon/chicken/duck/goose shops, with pigeon shops having the highest positivity rate (46.67%). The highest positivity rates were found in sewage (12.5%), poultry fecal (7.43%), cage swab (6.59%), avian pharyngeal/cloacal swab (3.33%), and air (2.29%) samples. The ompA sequences were identified in two strains of C. psittaci, which were determined to bear genotype B using phylogenetic analysis. Thus, during monitoring, C. psittaci genotype B was detected in the poultry and environmental samples from the poultry wholesale market in Changsha. CONCLUSIONS: To address the potential zoonotic threat, C. psittaci monitoring programs in live poultry markets should be enhanced.


Asunto(s)
Chlamydophila psittaci , Filogenia , Enfermedades de las Aves de Corral , Aves de Corral , Psitacosis , Animales , Chlamydophila psittaci/genética , Chlamydophila psittaci/aislamiento & purificación , Chlamydophila psittaci/clasificación , China/epidemiología , Psitacosis/microbiología , Psitacosis/veterinaria , Psitacosis/epidemiología , Aves de Corral/microbiología , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/epidemiología , Pollos/microbiología , Patos/microbiología , Heces/microbiología , Reacción en Cadena en Tiempo Real de la Polimerasa
2.
J Infect Public Health ; 15(6): 609-614, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35537237

RESUMEN

BACKGROUND: Despite substantial resources deployed to curb SARS-CoV-2 transmission, controlling the COVID-19 pandemic has been a major challenge. New variants of the virus are frequently emerging leading to new waves of infection and re-introduction of control measures. In this study, we assessed the effectiveness of containment strategies implemented in the early phase of the pandemic. METHODS: Real-world data for COVID-19 cases was retrieved for the period Jan 1 to May 1, 2020 from a number of different sources, including PubMed, MEDLINE, Facebook, Epidemic Forecasting and Google Mobility Reports. We analyzed data for 18 countries/regions that deployed containment strategies such as travel restrictions, lockdowns, stay-at-home requests, school/public events closure, social distancing, and exposure history information management (digital contact tracing, DCT). Primary outcome measure was the change in the number of new cases over 30 days before and after deployment of a control measure. We also compared the effectiveness of centralized versus decentralized DCT. Time series data for COVID-19 were analyzed using Mann-Kendall (M-K) trend tests to investigate the impact of these measures on changes in the number of new cases. The rate of change in the number of new cases was compared using M-K z-values and Sen's slope. RESULTS: In spite of the widespread implementation of conventional strategies such as lockdowns, travel restrictions, social distancing, school closures, and stay-at-home requests, analysis revealed that these measures could not prevent the spread of the virus. However, countries which adopted DCT with centralized data storage were more likely to contain the spread. CONCLUSIONS: Centralized DCT was more effective in containing the spread of COVID-19. Early implementation of centralized DCT should be considered in future outbreaks. However, challenges such as public acceptance, data security and privacy concerns will need to be addressed.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Pandemias/prevención & control , Control de Enfermedades Transmisibles , Trazado de Contacto
3.
Food Environ Virol ; 14(1): 30-39, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34997459

RESUMEN

In routine surveillance for avian influenza viruses (AIVs) in the environments of live poultry markets (LPMs), certain samples were positive for AIVs type A while negative for subtypes (e.g., H5, H7, and H9). However, little attention has been paid to these unsubtyped AIVs samples. To reveal the dynamic distribution and molecular characteristics of AIVs, especially the unsubtyped AIVs, we reported and analyzed 1969 samples collected from the water environments of LPMs in Changsha, China, from January 2014 to November 2018. Our results revealed that 1504 (76.38%) samples were positive for AIV type A. Of these samples, the predominant hemagglutinin (HA) subtype was H9, followed by H5 and H7 (P < 0.05). The positive rate of H5 subtype in water environmental samples exhibited seasonality, which reached a peak in each winter-spring season from January 2014 to March 2017. The positive rates of AIVs (including type A, subtype H9, and mixed subtype H5/H7/H9) in non-central-city regions were higher than that in the central-city regions (P < 0.05). Notably, 161 unsubtyped AIVs samples were detected during the routine surveillance. However, subtyping with the commercial kit further identified eight different HA and seven different neuraminidase subtypes. Analyses unraveled that further subtyped AIVs H1, H6, and H11 had only one basic amino acid (R or K) at the cleavage site and residues Q226 and G228 at the receptor-binding associated sites. Overall, in addition to H5, H7, and H9 subtypes, we should also pay attention to unsubtyped AIVs samples during the routine surveillance for AIVs in the environments of LPMs.


Asunto(s)
Virus de la Influenza A , Gripe Aviar , Animales , China/epidemiología , Virus de la Influenza A/genética , Aves de Corral , Agua
4.
Int J Infect Dis ; 108: 72-80, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34000420

RESUMEN

OBJECTIVES: To understand the transmission mechanisms of the avian influenza A(H5N6) virus. METHODS: This study explored the live poultry feeding and trading network (LPFTN) around Changsha city, China. Field epidemiological investigations were performed in Changsha to investigate the LPFTN with the environmental samples systematically collected during 2014-2015 to monitor and analyze the spread of the A(H5N6) virus. Two surveillance systems were also applied to find possible human cases of A(H5N6) infection. RESULT: The information of all the 665 live poultry farming sites, five wholesale markets, and 223 retail markets in Changsha was collected to investigate the LPFTN. Moreover, about 840 environmental samples were systematically collected from the LPFTN during 2014-2015 to monitor the spread of the A(H5N6) virus, with 8.45% (71/840) positive for the N6 subtype. Furthermore, the full genome sequences of 10 A(H5N6) viruses detected from the environmental samples were obtained, which were then characterized and phylogenetically analyzed with the corresponding gene segments of the A(H5N6) virus obtained from GenBank, to determine the source of human infection. CONCLUSION: It was demonstrated that the LPFTN provided a platform for the H5N6 transmission, and formed an infectious pool for the spread of the virus to humans.


Asunto(s)
Virus de la Influenza A , Gripe Aviar , Gripe Humana , Animales , China/epidemiología , Humanos , Gripe Aviar/epidemiología , Gripe Humana/epidemiología , Filogenia , Aves de Corral
5.
J Virol Methods ; 257: 79-84, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29729298

RESUMEN

As of Aug 25, 2017, 17 incidences of human infection and 6 deaths due to the novel H5N6 virus have been reported in China. Genetic analysis of the viral genome revealed that this reassortant virus is highly pathogenic to poultry, and that the virus has a risk of transmission to humans. Accordingly, the development of a rapid, sensitive, and specific molecular diagnostic assay is critical for public health. In this study, a real-time reverse-transcription PCR (RT-PCR) assay was developed to specifically detect the novel H5N6 virus, with primer pairs targeting the hemagglutinin and neuraminidase gene sequences of this virus. RNA was extracted from throat swab specimens from patients with influenza-like illness (ILIs), and environmental samples were collected from live poultry markets (LPMs) for H5N6 virus detection by real-time RT-PCR. The method was demonstrated to enable specific detection of the avian H5N6 virus, with no cross-reactivity with seasonal influenza viruses (H1N1, H1N1 pdm09, H3N2 or B); H5N1, H7N9, H9N2 viruses; or other human respiratory viruses. The detection limit of the assay was 1.0 × 101 copies per reaction for N6 and 1.0 × 102 copies per reaction for H5 assays. The assay is a powerful tool for rapid, sensitive, and specific detection of H5N6 virus infection in specimens derived from humans, animals, and the environment.


Asunto(s)
Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/diagnóstico , Gripe Humana/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Animales , China , Cartilla de ADN/genética , Microbiología Ambiental , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Humanos , Virus de la Influenza A/genética , Neuraminidasa/genética , Faringe/virología , Aves de Corral , Sensibilidad y Especificidad , Proteínas Virales/genética
6.
Artículo en Inglés | MEDLINE | ID: mdl-29637047

RESUMEN

In January 2016, two patients died of rabies after receiving kidney transplants from a common organ donor at a hospital in Changsha, Hunan, China. The medical records, epidemiological data of the organ donor, two kidney and a liver recipients were reviewed. Intravitam saliva samples of the two kidney recipients were tested for rabies virus (RABV) using real-time RT-PCR, and the nucleoprotein (N) gene was amplified and sequenced by Sanger sequencing. Whole genome sequences were analyzed using next-generation sequencing. The N genes of the two kidney recipients showed 100% nucleic acid identity. Phylogenetic analysis of the complete genome, N and glycoprotein (G) genes indicated that the RABV was homologous with dog isolates from the Hunan province and belong to the China I lineage, which is widespread in China. The organ donor was a 22-month-old boy who died from unknown acute progressive encephalitis. After undergoing sub-hypothermia hibernation therapy, rabies-associated symptoms were atypical, and rabies was neglected because serum RABV-specific antibodies were negative. An unknown wound on the forehead of the donor was found 2 months before the onset of symptoms. Based on the clinical, epidemiological, and molecular findings, we speculated that the RABV initially originated in the donor from a dog bite, and was then transmitted to the recipients by organ transplantation. An uncertain exposure history and misdiagnosis played important roles in the spread of the RABV. Rabies should be considered in patients with acute progressive encephalitis of unexplained etiology, especially in potential organ donors.


Asunto(s)
Trasplante de Riñón/efectos adversos , Trasplante de Hígado/efectos adversos , Complicaciones Posoperatorias/virología , Virus de la Rabia/aislamiento & purificación , Rabia/virología , Adulto , Anticuerpos Antivirales/sangre , China/epidemiología , Femenino , Humanos , Lactante , Riñón/cirugía , Riñón/virología , Hígado/cirugía , Hígado/virología , Masculino , Persona de Mediana Edad , Filogenia , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/epidemiología , Rabia/sangre , Rabia/epidemiología , Virus de la Rabia/clasificación , Virus de la Rabia/genética , Virus de la Rabia/inmunología , Donantes de Tejidos/estadística & datos numéricos
7.
Data Brief ; 12: 418-422, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28516136

RESUMEN

This data article contains data related to the research article entitled "Rapid detection of enterovirus and Coxsackievirus A10 by a TaqMan based duplex one-step real time RT-PCR assay" (Chen at al., 2017) [1]. Primers and probe sequence design are among the most critical factors in real-time polymerase chain reaction (PCR) assay optimization. Linearity, sensitivity, specificity and precision are the crucial criteria which are used to evaluate the performance of a new method. This data article report the primers and probe design and precision assessment of the new assay. VP1 gene of Coxsackievirus A10 (CV-A10) and 5'-NCR of different enterovirus (EV) serotypes were retrieved from GenBank database and aligned. The intra- and inter-assay variation were assessed using high, medium and low concentration of control plasmid DNA and viral RNA samples.

8.
Mol Cell Probes ; 33: 8-10, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28189797

RESUMEN

A TaqMan based duplex one-step real time RT-PCR (rRT-PCR) assay was developed for the rapid detection of Coxsackievirus A10 (CV-A10) and other enterovirus (EVs) in clinical samples. The assay was fully evaluated and found to be specific and sensitive. When applied in 115 clinical samples, a 100% diagnostic sensitivity in CV-A10 detection and 97.4% diagnostic sensitivity in other EVs were found.


Asunto(s)
Infecciones por Enterovirus/diagnóstico , Enterovirus/genética , Enterovirus/aislamiento & purificación , Técnicas de Diagnóstico Molecular , Antígenos Virales/genética , Antígenos Virales/aislamiento & purificación , Enterovirus/patogenicidad , Infecciones por Enterovirus/genética , Infecciones por Enterovirus/virología , Genotipo , Humanos
9.
J Am Heart Assoc ; 6(2)2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-28174167

RESUMEN

BACKGROUND: We previously reported that serum N1-methylnicotinamide (me-Nam), an indicator of nicotinamide N-methyltransferase activity, is associated with obesity and diabetes mellitus in Chinese patients. However, whether nicotinamide N-methyltransferase plays a role in human coronary artery disease (CAD) remains to be elucidated. We aim to investigate the associations of serum me-Nam with CAD in Chinese patients. METHODS AND RESULTS: Serum me-NAM was measured by liquid chromatography-mass spectrometry in patients with (n=230) or without (n=103) CAD as defined by coronary angiography. The severity of CAD was expressed by number of diseased coronary arteries. Serum me-Nam was higher (7.65 ng/mL versus 4.95 ng/mL, P<0.001) in patients with CAD than in those without. Serum me-Nam was positively correlated with high-sensitivity C-reactive protein and negatively correlated with high-density lipoprotein before and after adjustment for potential confounding variables (P≤0.002). In multivariable logistic regression analyses, compared with those in the lowest tertile of serum me-NAM levels, patients in the top tertile had the highest risks for CAD (odds ratio, 4.21; 95% CI, 1.97-8.97 [P<0.001]). After adjustment for potential confounding variables, serum me-NAM was also increased from 0- to 3-vessel disease (P for trend=0.01). CONCLUSIONS: Serum me-Nam is strongly associated with presence and severity of CAD, suggesting nicotinamide N-methyltransferase as a potential target for treating atherosclerosis in humans.


Asunto(s)
Índice de Masa Corporal , Enfermedad de la Arteria Coronaria/sangre , Diabetes Mellitus/epidemiología , Niacinamida/análogos & derivados , Obesidad/epidemiología , Anciano , Biomarcadores/sangre , China/epidemiología , Cromatografía Liquida/métodos , Comorbilidad , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/epidemiología , Diabetes Mellitus/sangre , Femenino , Humanos , Masculino , Espectrometría de Masas/métodos , Persona de Mediana Edad , Niacinamida/sangre , Nicotinamida N-Metiltransferasa/sangre , Obesidad/sangre , Reproducibilidad de los Resultados , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
10.
Infect Genet Evol ; 40: 236-242, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26973295

RESUMEN

A human infection with novel avian influenza A H5N6 virus emerged in Changsha city, China in February, 2014. This is the first detected human case among all human cases identified from 2014 to early 2016. We obtained and summarized clinical, epidemiological, and virological data from this patient. Complete genome of the virus was determined and compared to other avian influenza viruses via the construction of phylogenetic trees using the neighbor-joining approach. A girl aged five and half years developed fever and mild respiratory symptoms on Feb. 16, 2014 and visited hospital on Feb. 17. Throat swab specimens were obtained from the patient and a novel reassortant avian influenza A H5N6 virus was detected. All eight viral gene segments were of avian origin. The hemagglutinin (HA) and neuraminidase (NA) gene segments were closely related to A/duck/Sichuan/NCXN11/2014(H5N1) and A/chicken/Jiangxi/12782/2014(H10N6) viruses, respectively. The six internal genes were homologous to avian influenza A (H5N2) viruses isolated in duck from Jiangxi in China. This H5N6 virus has not gained genetic mutations necessary for human infection and was suggested to be sensitive to neuraminidase inhibitors, but resistant to adamantanes. Epidemiological investigation of the exposure history of the patient found that a live poultry market could be the source place of infection and the incubation period was 2-5days. This novel reassortant Avian influenza A(H5N6) virus could be low pathogenic in humans. The prevalence and genetic evolution of this virus should be closely monitored.


Asunto(s)
Virus de la Influenza A/clasificación , Virus de la Influenza A/genética , Gripe Aviar/epidemiología , Gripe Aviar/virología , Gripe Humana/epidemiología , Gripe Humana/virología , Sustitución de Aminoácidos , Animales , Aves , Pollos , China/epidemiología , Evolución Molecular , Genes Virales , Genoma Viral , Humanos , Gripe Humana/diagnóstico , Gripe Humana/tratamiento farmacológico , Filogenia , ARN Viral , Virus Reordenados
12.
Int J Infect Dis ; 33: 130-1, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25613667

RESUMEN

A novel H7N9 virus (A/Changsha/1/2013(H7N9)) identified through routine examination in the influenza network laboratory was analyzed retrospectively. The gene sequences of A/Changsha/1/2013(H7N9) were highly homologous to other viruses isolated in mainland China. Mutations of Q226L and G186V were found in the hemagglutinin protein (HA). Amino acid deletions were found at positions 69-73 of the neuraminidase protein (NA) and 218-230 of the non-structural protein (NS1). All viral genes except PB1 were essentially identical to the sequences of other Chinese influenza A H7N9 isolates. Overall, A/Changsha/1/2013(H7N9) is highly homologous to other H7N9 avian influenza viruses isolated in mainland China.


Asunto(s)
Subtipo H7N9 del Virus de la Influenza A/clasificación , Subtipo H7N9 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/virología , Secuencia de Aminoácidos/genética , Preescolar , China , Análisis Mutacional de ADN , Genes Virales , Humanos , Subtipo H7N9 del Virus de la Influenza A/genética , Masculino , Filogenia , Eliminación de Secuencia
13.
Int J Infect Dis ; 28: 17-25, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25236389

RESUMEN

BACKGROUND: During 2012, Changsha experienced a large outbreak of hand, foot, and mouth disease (HFMD), resulting in 25,438 cases, including 42 severe cases and eight deaths. METHODS: Seven hundred and forty-six clinical specimens were collected from hospital-based surveillance for HFMD in 2012. The detection and genotyping of enterovirus were performed by real-time RT-PCR and sequencing of the VP1 regions; phylogenetic analysis was performed based on the VP1 sequences. RESULTS: A total of 545 (73.1%) enterovirus-positive samples were identified, with the most frequently presenting serotype being enterovirus 71 (EV-71; n=364, 66.8%), followed by coxsackievirus A16 (CV-A16; n=84, 15.4%), CV-A6 (n=22, 4.0%), and CV-A10 (n=19, 3.5%). Most of the affected patients were children aged ≤5 years (n=524, 96.1%). EV-71 was the major pathogen in the severe and fatal cases (n=22, 78.6%). Phylogenetic analysis of VP1 gene sequences showed the EV-71 isolates to belong to subgenotype C4a, and the CV-A16 isolates to belong to subgenotype B1. The Changsha CV-A6 and CV-A10 circulating strains were homologous to strains circulating in other areas of mainland China. CONCLUSIONS: Our results demonstrate that EV-71 was the primary causative agent responsible for the HFMD outbreak in Changsha in 2012, and the co-circulation of other coxsackievirus A strains posed a potential risk to public health.


Asunto(s)
Brotes de Enfermedades , Enterovirus Humano A/clasificación , Enfermedad de Boca, Mano y Pie/epidemiología , Enfermedad de Boca, Mano y Pie/virología , Adolescente , Adulto , Niño , Preescolar , China/epidemiología , Enterovirus Humano A/genética , Enterovirus Humano A/aislamiento & purificación , Femenino , Genotipo , Humanos , Lactante , Masculino , Filogenia , Adulto Joven
14.
Exp Ther Med ; 7(5): 1369-1375, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24940441

RESUMEN

The aim of the present study was to analyze the evolution and variation of a novel strain of the avian influenza virus. The virus-positive specimens [A/Changsha/2/2013 (H7N9)] from a patient infected with the novel avian influenza A (H7N9) virus was amplified by reverse transcription-PCR and the full genome was sequenced. The sequencing results were submitted to GenBank and then analyzed by phylogenetic tree analysis using BioEdit and Mega5 software. The phylogenetic tree of the hemagglutinin (HA) and neuraminidase genes revealed that A/Changsha/2/2013 (H7N9) and all the new H7N9 viruses in 2013 were in a large cluster, and their nucleotide evolutionary distances were closely associated. Phylogenetic tree analyses of the nucleoprotein and nonstructural genes demonstrated two main branches. One branch contained novel H7N9 viruses isolated from avian, human and environmental sources in different regions. The other branch contained three novel H7N9 virus strains isolated from environmental sources in Shanghai. All the phylogenetic trees of the matrix protein, polymerase acidic, polymerase basic protein 1 and polymerase basic protein 2 genes also showed two branches, with each branch including the novel H7N9 virus strains isolated from avian, human and environmental sources in different regions. Molecular characterization demonstrated that 52 novel H7N9 viruses sequenced to date contain the G228S and G186V mutations in the receptor binding site of the HA protein. The full-genome sequences of A/Changsha/2/2013 and analyses of its molecular characteristics suggest that the A/Changsha/2/2013 H7N9 virus strain has molecular characteristics that may facilitate adaptation of the virus to mammalian hosts and may even bind to human receptors.

15.
Artículo en Inglés | MEDLINE | ID: mdl-24968671

RESUMEN

The objective of this study was to examine the circulating influenza viruses in Changsha, China, during 2010-2012. Nasopharyngeal specimens were collected from persons with influenza-like illness (ILI) who presented for care at two hospitals. Of 2,955 patients tested, 278/(9.4%) were positive for influenza virus: 116/(41.7%) were influenza type A(H3N2), 79/(28.4%) were type A(H1N1) pandemic 2009 (pdm09) and 83/(29.9%) were influenza type B. The rates of virus detection varied by age and sex. The highest rate was in the 5-14 year old age group and females were infected more than males. After the initial 2009 A(H1N1) pdm09 outbreak, the number of cases of this virus declined and the season become shorter. Influenza A(H3N2) and B viruses occurred mainly during the spring and summer, while influenza A(H1N1)pdm09 occurred mainly during the winter and spring. Influenza A(H1N1)pdm09 replaced the usual seasonal H1N1 virus during 2010-2012. Continuing epidemiological surveillance of influenza virus is important to monitor trends in influenza infections and to develop prevention and control measures.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Subtipo H3N2 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/epidemiología , Vigilancia de la Población , Adolescente , Adulto , Niño , Preescolar , China/epidemiología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Pandemias , Estaciones del Año , Factores Sexuales
16.
Zhonghua Liu Xing Bing Xue Za Zhi ; 33(8): 768-73, 2012 Aug.
Artículo en Chino | MEDLINE | ID: mdl-22967325

RESUMEN

OBJECTIVE: To investigate the risk of H5N1 subtype avian influenza virus (AIV) transmission in the poultry market environment in Changsha city. H5N1 antibody levels among the groups related occupational exposure and AIV nucleic acid in the environment of poultry markets were detected. The characteristics of haemagglutinin (HA) genes of H5N1 AIV in the environment were analyzed. METHODS: One district and one county from Changsha city were selected randomly and two poultry markets at inner city or township levels were selected in the same district or county respectively. H5N1 antibody of the occupational exposure groups in the poultry market was tested and AIV nucleic acid in the poultry market environment monitored. One hundred and two blood samples of the occupational exposure groups were tested for H5N1 antibody with single radioimmunoassay diffusion hemolysis (SRH) while 160 environment samples (from sewage, birds stools, feathers and smearing samples of poultry cages) in the poultry market were also detected for AIV nucleic acid with real-time PCR method. Four sewage samples of H5N1 subtype AIV were collected from poultry markets in Changsha, and the HA genes of H5N1 subtype AIV amplified by RT-PCR and then sequenced with TA cloning. Amino acid sequence alignment and phylogenetic tree analysis were conducted by Lasergene and Mega 5.0 software. RESULTS: The results through H5N1 antibody monitoring program showed that H5N1 antibody positive rates from workers were 25.5% (26/102), 50.0% (9/18) and 25.4% (17/67) respectively in the poultry markets of township and inner cities. H5N1 antibody positive rate in the township poultry markets was higher than in the inner cities poultry markets. RESULTS: from the surveillance on AIV nucleic acid showed that the overall H5 subtype positive rate in Changsha poultry markets was 31.3% (50/160), and the positive rate of townships poultry markets was 37.3% (31/83), which were both higher than those from the inner cities poultry markets (24.7%, 19/77). H5 subtype AIV positive rate was different in the tested specimens, with ranking of positive rates were sewage (50.0%, 24/48), feathers (44.5%, 4/9), birds stools (29.8%, 14/47) and smearing samples of poultry cages (14.3%, 8/56), with statistically significant differences (P < 0.01). Four H5N1 HA genes TA cloning were successfully constructed and identified as Eurasian branch, similar to viruses isolated in mainland China and Hong Kong in the same group, according to genetic analysis. Sequence data of the four HA genes showed the same feature of high pathogenicity, compared to the H5N1 AIV from mainland China of human origin. The receptor specificities were still with avian influenza origin (QSG) and the connecting peptide between HA1 and HA2 possessing the polybasic motif (RERRRKK or RERRGKK). CONCLUSION: One of the reasons for H5N1 antibody positive rate of 25.5% among poultry markets workers was that there were large numbers of H5N1 subtype AIV detected in the environment of poultry markets and HA genes of H5N1 subtype AIV in the poultry markets environment carried molecular characteristics of highly pathogenic which could increase the risk for H5N1 subtype AIV transmission in the environment of poultry markets.


Asunto(s)
Anticuerpos Antivirales/sangre , Gripe Aviar/epidemiología , Gripe Humana/epidemiología , Exposición Profesional , Animales , China/epidemiología , Monitoreo del Ambiente , Plumas/virología , Heces/virología , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/aislamiento & purificación , Humanos , Subtipo H5N1 del Virus de la Influenza A , Gripe Aviar/transmisión , Aves de Corral/virología , ARN Viral/aislamiento & purificación , Aguas del Alcantarillado/virología
17.
Bing Du Xue Bao ; 28(3): 265-71, 2012 May.
Artículo en Chino | MEDLINE | ID: mdl-22764530

RESUMEN

In order to investigate the transmission risk of H5N1 avian influenza viruses (AIV) from sewage in Changsha poultry markets, the evolution relationship and molecular characteristics of non-structural (NS) genes of H5N1 AIV from sewage were analyzed. Nine H5N1 AIV environmental sewage specimens were collected from Changsha poultry markets. The NS genes were amplifyed by PCR and then sequenced with TA cloning. Amino acid(aa) sequence alignment and phylogenetic tree analysis were conducted by Lasergene and Mega5 software. Eight NS genes TA cloning were constructed successfully. Phylogenetic tree indicated that they were belonged to the allele A subgroup. Aa homology analysis showed 90.1% 92.5% identity in NS1 proteins and 91.0% - 92.6% identity in NS2 proteins compared with reference viruses of the allele A (A/chicken/ Hubei/ w h/ 1999). The homologies of the amino sequences of NS1 and NS2 in this study were 93.8%-100.0% and 98.4%-100.0%, respectively. The C terminal of all eight H5N1 NS1 proteins from sewage in poultry markets carried a ESEV of PL motif and the 92 amino acids were E, furthermore, the 80 to 84aa were missed which were the characteristics of highly pathogenic AIV. The NS genes of H5N1 AIV from sewage in poultry markets have molecular characteristics of highly pathogenic and have the potential risk of H5N1 virus spreading.


Asunto(s)
Subtipo H5N1 del Virus de la Influenza A/genética , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/virología , Aguas del Alcantarillado/virología , Proteínas no Estructurales Virales/genética , Secuencia de Aminoácidos , Animales , Subtipo H5N1 del Virus de la Influenza A/química , Subtipo H5N1 del Virus de la Influenza A/clasificación , Gripe Aviar/transmisión , Datos de Secuencia Molecular , Filogenia , Aves de Corral , Homología de Secuencia de Aminoácido , Proteínas no Estructurales Virales/química
18.
Mol Biol Rep ; 39(1): 285-93, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21553056

RESUMEN

Many studies showed beneficial effects of either statin or bone marrow-derived mesenchymal stem cells (MSC) treatment in ischemic disease. In an attempt to further improve postischemic tissue repair, we investigated the effect of a local administration of MSC, in the presence or not of low-dose simvastatin, on angiogenesis and functional recovery in a mouse model of hindlimb ischemia. In vitro, the proliferation, migration, apoptosis, and tube formation of bone marrow MSC derived from transgenic mice expressing green fluorescent protein (GFP) were detected in the presence or not of 0.01 µmol/l simvastatin, respectively. In vivo, immediately after hindlimb ischemia, the mice were divided into four groups, namely control, MSC, statin, and statin-MSC, and received a single local injection of MSC (2×10(6) cells) and/or a repeated gavages' administration of simvastatin (0.2 mg/kg) for 21 days. The blood flow was measured by laser Doppler imaging, the capillary density was detected by alkaline phosphatase staining and, the MSC differentiation was assessed by immunofluorescent staining at 21 days after the ischemia. In vitro, the MSC proliferation rate, migration ability and tube formation number were increased significantly in simvastatin group relative to control group. Whereas, the H2O2 induced-apoptosis was inhibited significantly in simvastatin group relative to control group. In vivo, hindlimb blood reperfusion was significantly improved (MSC 0.55±0.08, statin 0.57±0.05, vs. control 0.47±0.07, P<0.05) and capillary density was obviously higher at day 21 post-ischemia by Laser Doppler Imaging in the MSC group and the Statin group when compared with control group. The combined use of statin and MSC further improved revascularization (perfusion ratio of 0.70±0.09; P<0.001 verse other groups) and resulted in the highest capillary density (P<0.05 vs. all other groups). GFP-labeled transplanted cells were more frequently observed in the Statin-MSC group than in the MSC group (6.8±0.5-3.1±0.7, P<0.05). Low-dose simvastatin could act in a synergistic way with MSC to potentiate the functional neovascularization in a mouse model of hind limb ischemia.


Asunto(s)
Miembro Posterior/irrigación sanguínea , Isquemia/tratamiento farmacológico , Isquemia/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Neovascularización Fisiológica/efectos de los fármacos , Simvastatina/farmacología , Análisis de Varianza , Animales , Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proteínas Fluorescentes Verdes/metabolismo , Peróxido de Hidrógeno , Flujometría por Láser-Doppler , Ratones , Ratones Transgénicos , Simvastatina/uso terapéutico
20.
Bing Du Xue Bao ; 25(4): 291-5, 2009 Jul.
Artículo en Chino | MEDLINE | ID: mdl-19769163

RESUMEN

To develop a reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay for rapid and sensitive detection of Norwalk GII. 4 primers which recognized 6 distinct regions on the RNA-dependent RNA polymerase gene of Norwalk GII were designed and used for LAMP assay. Norwalk GII RNA was amplified under isothermal conditions (65 degrees C) for 120 min, and LAMP results were then judged with naked eye, SYBR Green I staining, electrophoretic analysis and restriction digestion. To evaluate the specificity of the RT-LAMP, 48 fecal specimens of Norwalk GII and 12 fecal specimens of group A rotaviruses were tested. To compare the sensitivity of the RT-LAMP with that of conventional RT-PCR, Norwalk GII RNA was serially diluted and amplified by RT-LAMP and RT-PCR, respectively. With 46 fecal specimens of Norwalk GII, observation with naked eyes, SYBR Green I staining and electrophoretic analysis were able to detect the PCR products in the RT-LAMP assay. The specificity of RT-LAMP products was also confirmed by digestion of the RT-LAMP products with restriction enzymes. No RNA amplification was observed in 2 fecal specimens of Norwalk GII and 12 fecal specimens of group A rotaviruses. The specificity of the RT-LAMP assay with regard to RT-PCR were 100% for Norwalk GII. The detection limits of RT-LAMP was 15.6 pg/tube for Norwalk GII and similar to that of a RT-PCR assay. Compared to RT-PCR, the RT-LAMP assay has been proven to be a rapid, sensitive, specific and accurate method for detection of the Norwalk GII in fecal specimens, and that RT-LAMP assay is potentially useful for the rapid detection of Norwalk GII from fecal specimens in outbreaks of infectious diarrhea.


Asunto(s)
Infecciones por Caliciviridae/virología , Virus Norwalk/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Heces/virología , Humanos , Virus Norwalk/genética , ARN Polimerasa Dependiente del ARN/genética , Proteínas Virales/genética
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