Publications by authors named "Yan-Tao Wu"

21 Publications

  • Page 1 of 1

First report on the phylogenetic relationship, genetic variation of Echinococcus shiquicus isolates in Tibet Autonomous Region, China.

Parasit Vectors 2020 Nov 23;13(1):590. Epub 2020 Nov 23.

State Key Laboratory of Veterinary Etiological Biology/National Professional Laboratory for Animal Echinococcosis/Key Laboratory of Veterinary Parasitology of Gansu Province/Key Laboratory of Zoonoses of Agriculture Ministry, Lanzhou Veterinary Research Institute (CAAS), Lanzhou, 730046, Gansu, People's Republic of China.

Background: Cystic or alveolar echinococcosis caused by the larval stages of Echinococcus spp. is a very severe zoonotic helminth infection. Echinococcus shiquicus is a newly discovered species that has only been reported in the Qinghai and Sichuan provinces of the Qinghai-Tibet plateau, China where, to date, it has only been confirmed in Tibetan foxes and wild small mammal populations of the Tibetan plateau. Information on its genetic and evolutionary diversity is scanty. The aim of this study was to investigate the prevalence of E. shiquicus in plateau pikas (Ochotona curzoniae), a known intermediate host, and to determine the genetic variation and phylogenetic relationship of the E. shiquicus population in the Tibet region of China based on mitochondrial DNA.

Methods: Echinococcus shiquicus samples were collected from Damxung and Nyêmo counties (located in Tibet Autonomous Region, China). The mitochondrial cox1 and nad1 gene sequences were analyzed, and the genetic diversity and epidemiology of E. shiquicus in the region were discussed based on the results.

Results: The prevalence of E. shiquicus in pikas in Damxung and Nyêmo counties was 3.95% (6/152) and 6.98% (9/129), respectively. In combination with previous public sequence data, the haplotype analysis revealed 12 haplotypes (H) characterized by two distinct clusters (I and II), and a sequence distance of 99.1-99.9% from the reference haplotype (H1). The diversity and neutrality indices for the entire E. shiquicus populations were: haplotype diversity (Hd) ± standard deviation (SD) 0.862 ± 0.035; nucleotide diversity (Hd ± SD) 0.0056 ± 0.0003; Tajima's D 0.876 (P > 0.05); and Fu's F 6.000 (P > 0.05).

Conclusions: This was the first analysis of the newly discovered E. shiquicus in plateau pikas in the Tibet Autonomous Region of China. The neutrality indices suggest a deficiency of alleles, indicative of a recent population bottleneck.
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http://dx.doi.org/10.1186/s13071-020-04456-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7686673PMC
November 2020

Echinococcus granulosus (sensu stricto) (G1, G3) and E. ortleppi (G5) in Pakistan: phylogeny, genetic diversity and population structural analysis based on mitochondrial DNA.

Parasit Vectors 2020 Jul 13;13(1):347. Epub 2020 Jul 13.

State Key Laboratory of Veterinary Etiological Biology, National Professional Laboratory of Animal Hydatidosis, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, Gansu, People's Republic of China.

Background: Cystic echinococcosis (CE) is a serious tapeworm infection caused by Echinococcus granulosus (sensu lato) which infects a wide range of animals and humans worldwide. Despite the millions of livestock heads reared in Pakistan, only a few reports on CE prevalence and even fewer on the genetic diversity are available for the country. Meanwhile, the available reports on the genetic diversity are predominantly based on short sequences of the cox1 gene.

Methods: To close this knowledge gap, this study was designed to investigate the genetic diversity and population structure of Echinococcus spp. in Pakistan using the complete mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes.

Results: Based on BLAST searches of the generated cox1 and nad1 gene sequences from a total of 60 hydatid cysts collected from cattle (n = 40) and buffalo (n = 20), 52 isolates were identified as E. granulosus (s.s.) (G1, G3) and 8 as E. ortleppi (G5). The detection of the G5 genotype represents the first in Pakistan. The phylogeny inferred by the Bayesian method using nucleotide sequences of cox1-nad1 further confirmed their identity. The diversity indices indicated a high haplotype diversity and a low nucleotide diversity. The negative values of Tajima's D and Fu's Fs test demonstrated deviation from neutrality suggesting a recent population expansion.

Conclusions: To the best of our knowledge, this report described the genetic variation of E. granulosus population for the first time in Pakistan using the complete cox1 and nad1 mitochondrial genes and confirms E. ortleppi as one of the causative agents of CE among livestock in Pakistan. While this report will contribute to baseline information for CE control, more studies considering species diversity and distribution in different hosts across unstudied regions of Pakistan are highly needed.
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http://dx.doi.org/10.1186/s13071-020-04199-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7359271PMC
July 2020

Genetic variation of Echinococcus spp. in yaks and sheep in the Tibet Autonomous Region of China based on mitochondrial DNA.

Parasit Vectors 2019 Dec 27;12(1):608. Epub 2019 Dec 27.

State Key Laboratory of Veterinary Etiological Biology/National Professional Laboratory of Animal Hydatidosis, Key Laboratory of Veterinary Parasitology of Gansu Province/Lanzhou Veterinary Research Institute, CAAS, Lanzhou, 730046, Gansu, People's Republic of China.

Background: Cystic echinococcosis (CE) in humans and livestock is caused by Echinococcus granulosus (sensu lato). In China where CE is endemic, a number of studies have shown that Echinococcus granulosus (sensu stricto) is majorly responsible for CE. However, E. canadensis (G6) which is the second leading cause of CE is now being detected in most parts of the country. In this study, the species diversity and genetic variation of Echinococcus granulosus (s.l.) in four counties in Tibet Autonomous Region of China were investigated.

Methods: Infection with Echinococcus granulosus (s.s.) in yaks and sheep was identified using NADH dehydrogenase subunit 1 and 5 (nad1 and nad5) mitochondrial genes while the genotype G6 of E. canadensis initially diagnosed with NADH dehydrogenase subunit 1 (nad1) was further confirmed by analysis of the complete mitochondrial genome and a phylogenetic network constructed based on the nad2 and nad5 genes.

Results: Out of 85 hydatid cyst samples collected from slaughtered sheep (n = 54) and yaks (n = 31), 83 were identified as E. granulosus (s.s.) G1 (n = 77), G3 (n = 6) and 2 were identified as E. canadensis G6. Analysis of the nad1/nad5 genes revealed 16/17 mutations with 9/14 parsimony informative sites resulting in 15/14 haplotypes, respectively. Haplotype diversity (Hd) and nucleotide diversity (π) of E. granulosus (s.s.) population were 0.650 and 0.00127 for nad1 and 0.782 and 0.00306 for nad5, respectively, with an overall negative Tajima's D and Fu's Fs. A low F indicated no genetic difference between isolates from sheep and yaks.

Conclusion: Pockets of infection with E. canadensis (G6, G7, G8 and G10) have been previously reported in sheep, goats, yaks and/or humans in different parts of China. While the G6 genotype has been previously reported in sheep in the Tibet Autonomous Region, the detection in a yak in the present study represents the first to the best of our knowledge. Therefore, we recommend future surveys and control efforts to comprehensively investigate other potential intermediate hosts for the prevalence and genetic diversity of the E. canadensis group (G6, G7, G8 and G10) across the country and their inclusion into the existing CE control programme.
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http://dx.doi.org/10.1186/s13071-019-3857-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6935104PMC
December 2019

Correction to: First molecular description, phylogeny and genetic variation of Taenia hydatigena from Nigerian sheep and goats based on three mitochondrial genes.

Parasit Vectors 2019 11 21;12(1):547. Epub 2019 Nov 21.

State Key Laboratory of Veterinary Etiological Biology/National Professional Laboratory of Animal Hydatidosis/Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, People's Republic of China.

Following publication of the original article [1], the have authors flagged that the information in the legend of Fig. 1 is detailed in the wrong order.
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http://dx.doi.org/10.1186/s13071-019-3807-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6873671PMC
November 2019

First molecular description, phylogeny and genetic variation of Taenia hydatigena from Nigerian sheep and goats based on three mitochondrial genes.

Parasit Vectors 2019 Nov 5;12(1):520. Epub 2019 Nov 5.

State Key Laboratory of Veterinary Etiological Biology/National Professional Laboratory of Animal Hydatidosis/Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, People's Republic of China.

Background: Cysticercosis caused by the metacestode larval stage of Taenia hydatigena is a disease of veterinary and economic importance. A considerable level of genetic variation among isolates of different intermediate hosts and locations has been documented. Generally, data on the genetic population structure of T. hydatigena is scanty and lacking in Nigeria. Meanwhile, similar findings in other cestodes like Echinococcus spp. have been found to be of epidemiological importance. Our aim, therefore, was to characterize and compare the genetic diversity of T. hydatigena population in Nigeria based on three mitochondrial DNA markers as well as to assess the phylogenetic relationship with populations from other geographical regions.

Methods: In the present study, we described the genetic variation and diversity of T. hydatigena isolates from Nigerian sheep and goats using three full-length mitochondrial genes: the cytochrome c oxidase subunit 1 (cox1), NADH dehydrogenase subunit 1 (nad1), and NADH dehydrogenase subunit 5 (nad5).

Results: The median-joining network of concatenated cox1-nad1-nad5 sequences indicated that T. hydatigena metacestodes of sheep origin were genetically distinct from those obtained in goats and this was supported by high F values of nad1, cox1, and concatenated cox1-nad1-nad5 sequences. Genetic variation was also found to be higher in isolates from goats than from sheep.

Conclusions: To the best of our knowledge, the present study described the genetic variation of T. hydatigena population for the first time in Nigeria using full-length mitochondrial genes and suggests the existence of host-specific variants. The population indices of the different DNA markers suggest that analysis of long mitochondrial DNA fragments may provide more information on the molecular ecology of T. hydatigena. We recommend that future studies employ long mitochondrial DNA sequence in order to provide reliable data that would explain the extent of genetic variation in different hosts/locations and the biological and epidemiological significance.
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http://dx.doi.org/10.1186/s13071-019-3780-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6833231PMC
November 2019

A multiplex PCR assay for the simultaneous detection of Taenia hydatigena, T. multiceps, T. pisiformis, and Dipylidium caninum infections.

BMC Infect Dis 2019 Oct 16;19(1):854. Epub 2019 Oct 16.

State Key Laboratory of Veterinary Etiological Biology/ Key Laboratory of Veterinary Parasitology of Gansu Province/ Lanzhou Veterinary Research Institute, CAAS, Lanzhou, 730046, Gansu Province, People's Republic of China.

Background: Taenia hydatigena, T. multiceps, T. pisiformis, and Dipylidium caninum are four common large and medium-sized tapeworms parasitizing the small intestine of dogs and other canids. These parasites cause serious impact on the health and development of livestock. However, there are, so far, no commercially available molecular diagnostic kits capable of simultaneously detecting all four parasites in dogs. The aim of the study was therefore to develop a multiplex PCR assay that will accurately detect all four cestode infections in one reaction.

Methods: Specific primers for a multiplex PCR were designed based on corresponding mitochondrial genome sequences, and its detection limit was assessed by serial dilutions of the genomic DNAs of tapeworms examined. Furthermore, field samples of dog feces were tested using the developed assay.

Results: A multiplex polymerase chain reaction (PCR) assay was developed based on mitochondrial DNA (mtDNA) that accurately and simultaneously identify four cestode species in one reaction using specific fragment sizes of 592, 385, 283, and 190 bp for T. hydatigena, T. multiceps, T. pisiformis, and D. caninum, respectively. The lowest DNA concentration detected was 1 ng for T. hydatigena, T. multiceps and T. pisiformis, and 0.1 ng for D. caninum in a 25 μl reaction system. This assay offers high potential for the rapid detection of these four tapeworms in host feces simultaneously.

Conclusions: This study provides an efficient tool for the simultaneous detection of T. hydatigena, T. multiceps, T. pisiformis, and D. caninum. The assay will be potentially useful in epidemiological studies, diagnosis, and treatment of these four cestodes infections during prevention and control program.
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http://dx.doi.org/10.1186/s12879-019-4512-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6796438PMC
October 2019

Review of Cystic Echinococcosis in Nigeria: A Story of Neglect.

Acta Parasitol 2020 Mar 24;65(1):1-10. Epub 2019 Sep 24.

State Key Laboratory of Veterinary Etiological Biology/Key Laboratory of Veterinary Parasitology of Gansu Province/Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, Gansu Province, People's Republic of China.

Purpose: Cystic echinococcosis (CE) caused by Echinococcus granulosus sensu lato is a widespread zoonotic disease of global concern. In Nigeria, the exact picture/status of CE is unclear, as most of the states are largely uninvestigated. Yet, as with every parasitic zoonosis, the first step towards planning a comprehensive management and control programme involves assessment of available national/regional prevalence data, host range, and risk factors at play in the transmission dynamics.

Methods: Published articles on echinococcosis were searched on PubMed and Africa Journal Online (AJOL) databases. Inclusion criteria were based on studies reporting prevalence of echinococcosis in animals and humans (including case reports) from 1970 to 2018.

Results: In this study, we evaluated and summarized cystic echinococcosis reports in Nigeria and found that post 1970-80s, studies on cystic echinococcosis have remained sparse regardless of the high prevalence recorded in the early years of CE investigation. In addition, information on the genetic population structure and the role of wildlife in CE transmission is still lacking.

Conclusions: This study appraises the prevalence and distribution of CE in Nigeria and identified areas where surveillance and control efforts should be focused and intensified.
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http://dx.doi.org/10.2478/s11686-019-00124-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7223537PMC
March 2020

Cystic echinococcosis in Nigeria: first insight into the genotypes of Echinococcus granulosus in animals.

Parasit Vectors 2019 Aug 7;12(1):392. Epub 2019 Aug 7.

State Key Laboratory of Veterinary Etiological Biology/National Professional Laboratory of Animal Hydatidosis, Lanzhou Veterinary Research Institute, CAAS, Lanzhou, 730046, Gansu, P. R. China.

Background: Cystic echinococcosis (CE) is a zoonosis caused by cestodes of Echinococcus granulosus (sensu lato) complex. In Nigeria, reports on the prevalence of CE, although limited, have been found to vary with location and host with higher prevalence and fertility rate observed in camels than other livestock. Until now, information regarding the molecular characteristics, genetic population structure, and genotypes of Echinococcus is lacking. Therefore, this study was aimed at addressing these gaps in knowledge.

Methods: We describe the genetic status of 31 Echinococcus isolates collected from slaughtered livestock (camels, cattle and goats) based on the full-length mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes.

Results: The resulting nucleotide sequences via the NCBI BLAST algorithm and Bayesian phylogeny of cox1 and cox1-nad1 genes using MrBayes v.3.1.2 showed that all isolates were clearly E. canadensis (G6/G7) and were 99-100% identical to previously reported G6/G7 haplotypes across Europe, Asia, North and East Africa.

Conclusions: Although, the G1 genotype is believed to be responsible for the majority of global CE burden, reports from a number of West African countries including Nigeria suggest that E. canadensis G6/G7 genotype could be the major causative agent of CE in the subregion. This study provides for the first time insight into the genetic population structure of Echinococcus species as well as implications for CE control in Nigeria.
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http://dx.doi.org/10.1186/s13071-019-3644-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6686243PMC
August 2019

Newcastle disease virus NP and P proteins induce autophagy via the endoplasmic reticulum stress-related unfolded protein response.

Sci Rep 2016 Apr 21;6:24721. Epub 2016 Apr 21.

Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, P.R. China.

Newcastle disease virus (NDV) can replicate and trigger autophagy in human tumor cells. Our previous study confirmed the critical role of autophagy in NDV infection. Here we studied the role of NDV structural proteins in the induction of autophagy through endoplasmic reticulum (ER) stress-related unfolded protein response (UPR) pathways. Ectopic expression of the NDV nucleocapsid protein (NP) or phosphoprotein (P) was sufficient to induce autophagy. NP or P expression also altered ER homeostasis. The PERK and ATF6 pathways, but not the XBP1 pathway, all of which are components of the UPR, were activated in both NDV-infected and NP or P-transfected cells. Knockdown of PERK or ATF6 inhibited NDV-induced autophagy and reduced the extent of NDV replication. Collectively, these data suggest not only roles for the NDV NP and P proteins in autophagy, but also offer new insights into the mechanisms of NDV-induced autophagy through activation of the ER stress-related UPR pathway.
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http://dx.doi.org/10.1038/srep24721DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4838823PMC
April 2016

A thermo-stable lysine aminopeptidase from Pseudomonas aeruginosa: Isolation, purification, characterization, and sequence analysis.

J Basic Microbiol 2014 Oct 20;54(10):1110-9. Epub 2014 Jan 20.

Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.

Pseudomonas aeruginosa NJ-814, isolated from garden soil, produced an extracellular aminopeptidase that was purified using ammonium sulfate precipitation and ion exchange chromatography. The purity was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and the Mr value of the enzyme was estimated to be 55 kDa. The purified enzyme shows maximum activity at pH 9.0 and 80 °C. It exhibits high thermo-stability. Half of the activity can remain after incubation at 80 °C for 119 min. It is stable within pH range of 7.5-10.5. It is strongly activated by Co(2+) and inhibited by Fe(2+) , Cu(2+) , Ni(2+) , Zn(2+) , and ethylene diamine tetraacetic acid (EDTA). The specificity of the enzyme was investigated. Within several aminoacyl-p-nitroanilines (AA-pNA), Lys-pNA is proven to be the optimal substrate. The Michaelis-Menten constant (Km ) of the enzyme for Lys-pNA and Leu-pNA were 2.32 and 9.41 mM, respectively. Peptide map fingerprinting shows that the sequence of the enzyme is highly similar to aminopeptidase Y from P. aeruginosa 18A. It can be speculated that this enzyme is a Zn(2+) -dependent enzyme and contains two zinc ions in its active site.
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http://dx.doi.org/10.1002/jobm.201300752DOI Listing
October 2014

[Construction of recombinant fowlpox virus coexpressing HA gene from H5N1 avian influenza virus and chicken interleukin-2 gene and assessment of its protective efficacy].

Bing Du Xue Bao 2009 Nov;25(6):430-6

Key Laboratory of Animal Infectious Diseases, Ministry of Agriculture, Yangzhou University, Yangzhou 225009, China.

The hemagglutinin (HA) gene from H5N1 avian influenza virus and the chicken interleukin 2 (chiIL-2) gene were inserted into a expressing vector p12LS to construct a recombinant transferring vector p12LSH5AIL2, in which HA gene under the control of the promoter Ps was in inverse tandem connection with the chiIL-2 gene under the control of the promoter PE/L. The p12LSH5AIL2 was then used to transfect the chicken embryo fibroblasts (CEF) pre-infected with a wild-type fowlpox virus 282E4 strain, to generate a recombinant fowlpox virus coexpressing the inserted HA and chiIL2 genes (rFPV-H5AIL2). The rFPV-H5AIL2 was obtained and purified by blue plaque screening on the CEF. The in vitro expression of HA gene by rFPV-H5AIL2 was detected in the recombinant fowlpox virus-infected CEFs with an indirect immunofluorescence assay, and the expression of the chiIL2 gene by rFPV-H5AIL2 was confirmed by detection of the chiIL2 mRNA by RT-PCR and by detection of chiIL2 by the indirect immunofluorescence assay. Experiments on SPF and commercial chickens demonstrated that the titer for HI antibodies induced by the rFPV-H5AIL2 was significantly higher than that by the rFPV-HA. The group immunized with the rFPV-H5AIL2 exhibited the similar ratios of protective efficacy and virus shedding as the group immunized with the rFPV-HA in SPF chicken. However, in commercial chicken, the group immunized with the rFPV-H5AIL2 generated significantly higher protection against H5N1 avian influenza virus challenge and lower virus shedding than the group immunized with the rFPV-HA. This study paved the way for further development of a new AIV recombinant vaccine.
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November 2009

[The change of glucagon-like peptide-1 and its effect on blood glucose metabolism after major surgery].

Sichuan Da Xue Xue Bao Yi Xue Ban 2008 Jan;39(1):66-8, 88

Department of General Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.

Objective: To investigate the change of glucagon-like peptide-1(GLP-1) and its effect on blood glucose metabolism after major surgery.

Methods: Eleven patients, who had undergone major surgical procedures in our Department of General Surgery, were studied on the day before surgery, the first, third, and fifth day after surgery. Then, 42 rats were allocated randomly into three groups. The rats in control, which had not undergone any operation, received an intravenous glucose load (0.5 g/kg glucose + normal saline). The rats in operated group, which had undergone about 65% liver resection, received a same glucose load on the first, third,and fifth postoperative day. And the rats in GLP-1 group, which had undergone same hepatectomy, received a same glucose load with GLP-1 (0.3 nmol/kg) on the first, third,and fifth day after surgery. All rats would be killed by abdominal aorta exsanguinated in five minutes after drugs were infused of which the bloods were collected for determination of glucose (glucose oxidase), insulin, glucagon, and GLP-1 (radioimmunoassays) at each time-point.

Results: There was an increasing postoperative plasma concentration of glucose, insulin, and glucagon on the first day (P < 0.01), but the plasma GLP-1 was just elevated on the third day (P < 0.05). Then, the plasma glucose concentration was significantly lowered after GLP-1 given to rats undergoing hepatectomy (P < 0.001), which might reach the glucose range in controls. Lowering of blood glucose was achieved by a significant rise of insulin secretion (P < 0.001) and a suppression of glucagon secretion (P < 0.05).

Conclusion: As far as can be concluded on basis of our data from patients and rats, GLP-1 can be used to reduce the plasma glucose concentrations when it is in stress status after major surgery.
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January 2008

Virulence of H5N1 avian influenza virus enhanced by a 15-nucleotide deletion in the viral nonstructural gene.

Virus Genes 2008 Jun 4;36(3):471-8. Epub 2008 Mar 4.

Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China.

More and more H5N1 subtype avian influenza viruses possessing a 15-nucleotide (15-nt) deletion in the viral nonstructural protein (NS) gene from position 263 to 277 have emerged since 2000. In order to investigate the biological significance of this deletion, two pairs of H5N1 reassortants designated as rWSN-SD versus rWSN-mSD and rWSN-YZ versus rWSN-mYZ were generated by reverse genetics technique. These recombinant viruses shared the same inner genes of PB1, PB2, PA, NP, and M from strain A/WSN/33(H1N1) and outer genes of HA and NA from strain A/Duck/Shandong/093/2004 (H5N1) (A/D/SD/04), whereas they bore different NS gene. Recombinant rWSN-SD carried the full sequence NS gene from A/D/SD/04 in the natural state without deletion, whereas rWSN-mSD carried the same NS gene, but with an artificial 15-nt deletion from position 263 to 277. On the other hand, rWSN-YZ contained the NS gene in the natural state with a deletion from A/Duck/Yangzhou/232/2004 (H5N1) (A/D/YZ/04), while rWSN-mYZ bore the same NS gene but with an artificial insertion of 15-nt in site 263-277. All the four reassortants grew well in embryonated chicken eggs with similar mean death time (MDT) and viral titer of EID50 or HA. However, the virulence of these reassortant viruses in chickens and mice was different. Reassortant viruses with deletion in their NS gene (rWSN-mSD and rWSN-YZ) had much higher intraveneous pathogenicity index (IVPI) in chickens and lower MLD50 in mice than their counterparts without the deletion (rWSN-SD and rWSN-mYZ). Furthermore, rWSN-mSD and rWSN-YZ caused significantly more deaths in infected chickens and higher virus titers in tissues of inoculated mice than did rWSN-SD and rWSN-mYZ respectively. Sequence analysis also showed that H5N1 viruses carrying the 15-nt deletion in the NS gene invariably had the D92E shift in their NS1 protein. The results indicated that the 15-nucleotide deletion of NS gene from site 263 to 277 associated with D92E shift in NS1 protein contributes to the virulence increase of H5N1 viruses in chickens and mice.
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http://dx.doi.org/10.1007/s11262-007-0187-8DOI Listing
June 2008

[Clinical observation on TCM treatment according to syndrome differentiation in relieving acute radio-reaction in nasopharyngeal carcinoma patients].

Zhongguo Zhong Xi Yi Jie He Za Zhi 2007 May;27(5):452-5

Department of Otorhinolaryngology , Nankai Hospital, Tianjin.

Objective: To observe the effect of traditional Chinese medicine (TCM) treatment according to syndrome differentiation on acute radio-reaction (ARR) in nasopharyngeal carcinoma (NPC) patients.

Methods: One hundred and ninety-five NPC patients who received radiotherapy (RT) for the first time were randomly assigned to two groups: the control group (89 cases) was treated by RT alone for 7 weeks and the treatment group (106 cases) was treated by RT combined with oral taking TCM from starting of RT till 5 weeks after RT. The overall changes in total ARR score and ARR in different locations were observed weekly and compared.

Results: The total ARR score in the treatment group was significantly lower than that in the control group (P<0.05). And the ARR scores of different organs, including skin, oropharyngeal mucosa, salivary glands, larynx, car, upper digestive tract, and central nervous system, in the treatment group were all lower than those of the corresponding organs in the control group. In addition, the ARR scores in both groups showed an ascending trend in the first 7 weeks and a descending trend from the 8th to the 10th week after beginning RT.

Conclusion: TCM treatment could relieve the ARR in the NPC patients without any affection on the efficacy of RT.
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May 2007

[Attenuation of a genotype VIId Newcastle disease virus ZJI strain of goose origin by reverse genetics].

Wei Sheng Wu Xue Bao 2007 Apr;47(2):197-200

Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China.

Based on the complete genome sequence of Newcastle disease virus (NDV) ZJI strain isolated from an outbreak in the goose, seven pairs of primers were designed to amplify cDNA fragment for constructing the plasmid pNDV/ZJI, which contained the full-length cDNA of NDV ZJI strain. The pNDV/ZJI with three helper plasmids, pCI-NP, pCI-P and pCI-L, were then cotransfected into BSR-T7/5 cells expressing T7 RNA polymerase. After inoculation of the transfected cell culture supernatant into embryonated chicken eggs from specific-pathogen-free (SPF) flock, infectious NDV ZJI strain was successfully rescued. The recombinant plasmid pNDV/ZJIFM was generated by converting the multi-basic amino acid sequence of the F0 protein cleavage region in pNDV/ZJI to the non-basic amino acid sequence characteristic of avirulent NDV strain. After cotransfection of the resultant plasmid and the three helper plasmids into BSR-T7/5 cells, the recombinant NDV, NDV/ZJIFM, was generated. The mean death time (MDT) of NDV/ZJIFM was more than 120h and the intrancerebral pathogenicity index (ICPI) was 0.16, indicating that the rescued virus was highly attenuated. This attenuated genotype VIId NDV of goose origin could be a desirable vaccine in controlling the current epidemic of ND.
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April 2007

[The mechanism and significance of cellular signal transduction in kidney glomerular mesangial cells of rat with obstructive jaundice].

Sichuan Da Xue Xue Bao Yi Xue Ban 2007 Jan;38(1):116-8

Department of General Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.

Objective: To study the mechanism of ceramide-induced cellular signal transduction and its effect on renal injury.

Methods: Sixty male Sprague-Dawley rats were randomly assigned to four groups (n = 15): control group, sham operation group, experiment group one and experiment group two. Except the control and the sham operation group, the other two experiment groups underwent the common bile duct bound to form the rat model of obstructive jaundice. The renal glomerular mesangial cells (GMC) were cultured primarily. After GMC were given different stimulating factors, we performed the measurement of the PLD activity and the GMC apoptosis analyzed by flow cytometry.

Results: The biological activity of PC-PLD was significantly decreased by TNF-alpha and ceramide (P< 0.05). On the other hand, the GMC apoptosis was induced by TNF-alpha and ceramide (P <0. 05). However, other opposite results were obtained in addition of ceramide inhibitor to GMC.

Conclusion: TNF-alpha can induce the ceramide increase in GMC, which is significant to effect on the kidney injury of the rats with obstructive jaundice, by the means of inducing GMC apoptosis and decreasing the activity of PC-PLD.
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January 2007

[Biological significance of amino acids deletion in NA stalk of H5N1 avian influenza virus].

Wei Sheng Wu Xue Bao 2006 Aug;46(4):542-6

Key Laboratory of Animal Infectious Diseases, Ministry of Agriculture, Yangzhou University, Yangzhou 225009, China.

It has been reported that NA gene of some H1N1 Influenza A virus strains isolated since 1933 is characterized by a deletion of 11 to 16 amino acids in the stalk. The spontaneous mutant in NA stalk of H1N1 virus lacks enzyme activity with large substrate (fetuin) but not with small substrate (sialyllactose). Recently, H5N1 virus also has been found that NA has the same unique mutation in the stalk, a deletion of 15 to 20 amino acids. However, biological significance of this mutation has not yet been reported. In order to investigate biological significance of the amino acids deletion in NA stalk of H5N1, five reassorted H5N1/PR8 viruses were generated via eight-plasmid based reverse genetics system. These five viruses were named 506, m506-, 646, m646+ and 196, respectively. The six internal genes of recombinants were all from A/PR8/34(H1N1), and HA gene was from A/G/JS/03(H5N1), however, they had different NA genes. 506 and m506- held NA fragments derived from A/G/HD/00(H5N1), and the former was distinguished with a longer NA which had no 20 amino acids deletion in the stalk. 646 and m646+ held NA fragments from A/G/JS/03(H5N1), and the NA stalk of m646+ was 20 amino acids longer than that of 646. The NA of 196 was derived from A/PR8/34 which had 15 amino acids deletion in its stalk. Biological characteristics of these viruses showed that recombinants with different NA length could grow well in embryonated SPF eggs, and their EID50, MDT, and viral titers were similar. However, the length of NA was related to the capacity of eluting viruses from erythrocytes for 506 and 646+ which holding longer NA stalks eluted from erythrocytes more quickly than m506-, 646 and 196 did. Moreover, 15 or 20 amino acids deletion in NA stalk had a pronounced effect on virus growth ability in MDCK cells. Viral titers in supernatant of MDCK infected with m506- or 646 were 10 to 100 folds higher than those infected by 506 or m646+. And the plaque size of m506- and 646 were larger than that of 506 and m646+. The results reveals that H5N1 AIV with amino acids deletion in NA stalk would expand its host range. The unique amino acids deletion in NA molecule of H5N1 may be associated with the adaptation of virus to terrestrial poultry or the increasing ability of interspecies transmission.
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August 2006

[Establishment of reverse genetics system for H5N1 subtype AI].

Wei Sheng Wu Xue Bao 2006 Feb;46(1):55-9

Key Laboratory of Animal Infectious Diseases of Ministry of Agriculture, Yangzhou University, Yangzhou 225009, China.

H5N1 subtype influenza virus A/Duck/Shandong/093/2004 (A/SD/04) strain was chosen as the master strain for rescue research. 11 sets of primers for 8 plasmids construction were designed base on the sequencing of the full-length of A/SD/04. Eleven fragments of A/SD/04 were amplified by the designed primers and were ligated with PHW2000 for rescue plasmid construction. Eight transcription/expression plasmids were obtained, which encoded the eight segments of A/SD/04, and designated as 241, 242, 243, 244, 245, 246, 247 and 248, respectively. The COS-1 cell was cotransfected with eight plasmids with different combination of A/SD/04 and PR8. The eight reassortants shared the same HA (from A/SD/04) but contained different internal genes and NA. All of the eight reassorted viruses had some similar bio-characteristics, such as the viral title in fertilized eggs was range from 256 to 1024, the EID50 were between 10(-8.5) to approximately 10(-9), and MDT were between 34 to approximately 46h. But the IVPI of the eight reassortants was differently and all were lower than the wild-type A/SD/04. These results confirmed that different recombination of internal genes of H5N1 has influence on viral virulence to 6-week SPF chicken but not on viral replication ability in embryonated chicken eggs. The establishment of eight-plasmid rescue system for A/SD/04 is the base for farther research on genes function of H5N1. And A/SD/04 can be used as a backbone to replace PR8 entirely in generation of H5 AIV vaccine candidate.
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February 2006

[Generation of newcastle disease virus strain ZJI isolated from an outbreak in the goose using reverse genetics technique].

Wei Sheng Wu Xue Bao 2005 Oct;45(5):780-3

Animal Infectious Disease Laboratory, School of Veterinary Medicine, Yangzhou University, China.

The full-length cDNA clone, NDV3GM122, and the three helperplasmids pCI-NP, pCI-P and pCI-L of Newcastle disease virus strain ZJI isolated from an outbreak in the goose were cotransfected into BSR-T7/5 cell expressing T7 RNA polymerase. Meanwhile, the full-length cDNA clone NDV3GM122 and the three helperplasmids, pCIneoNP, pCIneoP and pCIneoL which were derived from NDV strain La Sota, were also cotransfected into the cell, respectively. Indiect immunofluorescence assay (IFA) was performed 48 to 96 hours post-transfection using NDV HN-specific monoclonal anbtibody (McAb) 6B1 and bright stainings were found in the transfectants, indicating that the full-length clone was functional and the HN protein was expressed. The transfected cell and the supernatant were mixed well and thereafter the mixture was inoculated into specific pathogen free (SPF) chicken eggs. The allanotoic fluid of the injected eggs gave a positive hemagglutinin( HA) titer ranging from 16 to 32 in the secondary passage and increased to 128 in the third passage, which was same to the level of parent wild-type virus. The allantoic fluid containing the recovered NDV was analyzed in hemagglutination inhibition( HI) test by using McAb 6B1 and the specific inhibition was found. The typical morphology of the produced NDV was detected in the electronic microscope. The results mentioned above demonstrated that infectious NDV of strain ZJI was successfully generated, which laid good foundation for the further related research.
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October 2005

Venovenous bypass ahead of mobilization of the liver in orthotopic liver transplantation.

Hepatobiliary Pancreat Dis Int 2003 Feb;2(1):44-7

Center of Liver Transplantation, West China Hospital, Sichuan University, Chengdu 610041, China.

Background: To evaluate feasibility and safety of venovenous bypass prior to mobilization of the liver during orthotopic liver transplantation (OLT).

Methods: Fifty-four patients were classified into two groups. Group A consisted of 23 patients receiving OLT with classical venovenous bypass. Group B consisted of 31 patients who received a modified-procedure: venovenous bypass ahead of the mobilization of the liver during OLT. The blood loss, duration of venovenous bypass, cold ischemia time, anhepatic phase, and transfusion during operation in the two groups were compared. Complications after the operation were also compared between the two groups.

Results: The duration of venovenous bypass and cold ischemia time in group A were longer than those in group B [(99.78+/-21.36 min) vs (96.32+/-22.25 min) and (484.78+/-134.01 min) vs (443.15+/- 85.27 min)]. The anhepatic phase lasted for about 100 min averagely in the two groups. The volumes of blood loss and transfusion during the operation were larger in group A than in group B [(5096+/-4243 ml) vs (1726+/-1125 ml) and (3676+/-2938.74 ml) vs (1217.69+/-829.72 ml)]. Postoperative complications occurred in 26 patients of group A and in 19 patients of group B.

Conclusion: This modified-procedure or venovenous bypass ahead of mobilization of the liver in OLT can reduce the blood loss during OLT and the incidence of postoperative complications without prolongation of the anhepatic phase and duration of venovenous bypass.
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February 2003

Hepatic adenylate energy charge levels in patients with hepatoma after hepatic artery embolization.

World J Gastroenterol 1998 Apr;4(2):109-111

AIM:To evaluate hepatic energy charge levels of the patients with hepatoma after hepatic artery embolization and its relation to postoperative complications.METHODS:Sixty-nine patients with hepatoma were continuously measured for their arterial blood ketone body ratio (AKBR) and compared with their postoperative clinical course or conventional liver function test after various hepatic artery embolization.RESULTS:AKBR in high radiation dose or jaundice group drastically decreased at 1-3 days and recovered slowly. Patients were classified into three groups according to the value of AKBR: group A (35 cases), AKBR remained higher than 0.7; group B (31 cases), AKBR had transiently dropped to 0.4-0.7 and then increased to preoperative value; and group C (3 cases), AKBR decreased steadily to below 0.4.The occurrence rate of various complications were 5.7%, 32.3% and 100% in the three groups, respectively (P < 0.005).CONCLUSION:The AKBR which reflects hepatic mitochondria redox state is more reliable as a direct indicator to assess hepatic tolerance for embolization than routine liver function test.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4688628PMC
http://dx.doi.org/10.3748/wjg.v4.i2.109DOI Listing
April 1998