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Roland Zell - One of the best experts on this subject based on the ideXlab platform.

  • characterization of ptv 12 a newly described porcine Teschovirus serotype in vivo infection and cross protection studies
    Journal of General Virology, 2017
    Co-Authors: Cristina Canogomez, Roland Zell, Jovita Fernandezpinero, Maria Ana Garciacasado, Miguel Angel Jimenezclavero
    Abstract:

    Porcine Teschoviruses (PTVs) constitute 1 of the 31 genera within the Picornaviridae family, comprising at least 13 genetic types (PTV-1 to PTV-13), of which only 11 (PTV-1 to PTV-11) have been recognized as serotypes to date. Specific for swine and wild boars, most PTVs are usually non-pathogenic, but some viral variants cause severe disorders in the central nervous system (Teschen disease) or milder signs (Talfan disease), as well as reproductive, digestive and respiratory disorders and skin lesions. Previous studies revealed a high diversity of Teschoviruses circulating in Spanish pig populations. Phylogenetic analysis performed with these sequences and others available in GenBank disclosed 13 clusters, 11 of which corresponded to the known PTV serotypes, and 1 of 2 additional groups is represented by isolate CC25, whose full-length genomic sequence has been obtained. This group is new to science, and was putatively named PTV-12. Here, a complete characterization of this isolate is presented, including the experimental infection of minipigs to assess tissue tropism and possible pathogenicity in vivo in the host species. In addition, using this experimental animal model, we investigated whether a pre-existing infection with this PTV-12 isolate could confer cross-protection against infection with a heterotypic PTV-1 virulent strain. Based on phylogenetic analysis and serological data, we propose CC25 as the prototype strain of a new Teschovirus serotype, PTV-12.

  • A manual and an automatic TERS based virus discrimination
    Nanoscale, 2015
    Co-Authors: Konstanze Olschewski, Roland Zell, Thomas Bocklitz, Evelyn Kämmer, Stephan Stöckel, Dana Cialla-may, Karina Weber, Volker Deckert, Tanja Deckert-gaudig, Jürgen Popp
    Abstract:

    Rapid techniques for virus identification are more relevant today than ever. Conventional virus detection and identification strategies generally rest upon various microbiological methods and genomic approaches, which are not suited for the analysis of single virus particles. In contrast, the highly sensitive spectroscopic technique tip-enhanced Raman spectroscopy (TERS) allows the characterisation of biological nano-structures like virions on a single-particle level. In this study, the feasibility of TERS in combination with chemometrics to discriminate two pathogenic viruses, Varicella-zoster virus (VZV) and Porcine Teschovirus (PTV), was investigated. In a first step, chemometric methods transformed the spectral data in such a way that a rapid visual discrimination of the two examined viruses was enabled. In a further step, these methods were utilised to perform an automatic quality rating of the measured spectra. Spectra that passed this test were eventually used to calculate a classification model, through which a successful discrimination of the two viral species based on TERS spectra of single virus particles was also realised with a classification accuracy of 91%.

  • Single virus detection by means of atomic force microscopy in combination with advanced image analysis.
    Journal of Structural Biology, 2014
    Co-Authors: Thomas Bocklitz, Roland Zell, Evelyn Kämmer, Stephan Stöckel, Dana Cialla-may, Karina Weber, Volker Deckert, Jürgen Popp
    Abstract:

    Abstract In the present contribution virions of five different virus species, namely Varicella-zoster virus , Porcine Teschovirus , Tobacco mosaic virus , Coliphage M13 and Enterobacteria phage PsP3 , are investigated using atomic force microscopy (AFM). From the resulting height images quantitative features like maximal height, area and volume of the viruses could be extracted and compared to reference values. Subsequently, these features were accompanied by image moments, which quantify the morphology of the virions. Both types of features could be utilized for an automatic discrimination of the five virus species. The accuracy of this classification model was 96.8%. Thus, a virus detection on a single-particle level using AFM images is possible. Due to the application of advanced image analysis the morphology could be quantified and used for further analysis. Here, an automatic recognition by means of a classification model could be achieved in a reliable and objective manner.

  • phylogeny and evolution of porcine Teschovirus 8 isolated from pigs in china with reproductive failure
    Archives of Virology, 2012
    Co-Authors: Roland Zell
    Abstract:

    A porcine Teschovirus (PTV) was isolated from a dead piglet from a herd of 200 sows showing reproductive failure in Fuyu, Heilongjiang Province, China. Sequencing of most of the genome of this isolate, designated Fuyu/2009, revealed that is was a PTV-8 isolate, closely related to a previously identified Chinese PTV-8 strain (Jilin/2003). Both Chinese strains vary from the European PTV-8 strains by different clustering of the 3CD sequences. Infection with these viruses may be associated with pronounced diseases.

  • isolation and characterization of the first chinese strain of porcine Teschovirus 8
    Journal of Virological Methods, 2010
    Co-Authors: Chaofan Zhang, Shouping Hu, Zhuo Zhang, Roland Zell
    Abstract:

    Investigations were carried out to identify the causal agent of acute diarrhea, respiratory distress, and death of pigs on a swine farm in Jilin Province, northern China. Only porcine Teschovirus (PTV, designated as PTV-8 Jilin/2003) was isolated from samples of organs. The presence of PTV was confirmed by the production of a specific cytopathic effect on susceptible cells and by the results of the immunoperoxidase monolayer assay (IPMA), polymerase chain reaction, and electron microscopy. Other pathogenic agents causing diarrhea, respiratory distress, and death (including porcine rotavirus, transmissible gastroenteritis virus of swine, porcine epidemic diarrhea virus, classical swine fever virus, pseudorabies virus, porcine circovirus, porcine reproductive and respiratory syndrome virus, Japanese encephalitis virus, Mycoplasma, Leptospira, Streptococcus, Listeria, and Brucella species) were excluded as possible causal agents because they were not associated consistently with the disease of the pigs. PTV-8 Jilin/2003 was adapted to grow in swine primary kidney (PK-15) cells and in a swine testicular cell line (ST cells). When inoculated into healthy pigs, PTV-8 Jilin/2003 caused the same symptoms as those observed in the affected herd. It is concluded that PTV-8 Jilin/2003 was the causal agent of this disease.

Graham J. Belsham - One of the best experts on this subject based on the ideXlab platform.

  • Divergent picornavirus IRES elements.
    Virus Research, 2008
    Co-Authors: Graham J. Belsham
    Abstract:

    Internal ribosome entry site (IRES) elements were first identified about 20 years ago within the 5' untranslated region of picornavirus RNAs. They direct a cap-independent mechanism of translation initiation on the viral RNA. Within the picornavirus family it is now known that there are four classes of IRES element which vary in size (450-270 nt), they also have different, complex, secondary structures and distinct requirements for cellular proteins to allow them to function. This review describes the features of each class of picornavirus IRES element but focuses on the characteristics of the most recently described group, initially identified within the porcine Teschovirus-1 RNA, which has strong similarities to the IRES elements from within the genomes of hepatitis C virus and the pestiviruses which are members of the flavivirus family. The selection of the initiation codon by these distinct IRES elements is also discussed.

  • Hepatitis C virus-related internal ribosome entry sites are found in multiple genera of the family Picornaviridae.
    Journal of General Virology, 2006
    Co-Authors: Louisa S. Chard, Marie-eve Bordeleau, Jerry Pelletier, Junichi Tanaka, Graham J. Belsham
    Abstract:

    The internal ribosome entry site (IRES) elements from porcine enterovirus 8 and simian virus 2, two members of a proposed new genus within the family Picornaviridae, were characterized. These IRES elements, in common with the porcine Teschovirus 1 IRES, were found to be related functionally and structurally to the IRES element from Hepatitis C virus, a member of the family Flaviviridae. Partial secondary structure predictions were derived and functional assays demonstrated that these IRES elements continued to be active when eIF4G was cleaved and when the activity of eIF4A was blocked.

  • functional analyses of rna structures shared between the internal ribosome entry sites of hepatitis c virus and the picornavirus porcine Teschovirus 1 talfan
    Journal of Virology, 2006
    Co-Authors: Louisa S. Chard, Y Kaku, Barbara Jones, Arabinda Nayak, Graham J. Belsham
    Abstract:

    The internal ribosome entry site (IRES) of porcine Teschovirus 1 (PTV-1), a member of the Picornaviridae family, is quite distinct from other well-characterized picornavirus IRES elements, but it displays functional similarities to the IRES from hepatitis C virus (HCV), a member of the Flaviviridae family. In particular, a dominant negative mutant form of eIF4A does not inhibit the activity of the PTV-1 IRES. Furthermore, there is a high level (ca. 50%) of identity between the PTV-1 and HCV IRES sequences. A secondary-structure model of the whole PTV-1 IRES has been derived which includes a pseudoknot. Validation of specific features within the model has been achieved by mutagenesis and functional assays. The differences and similarities between the PTV-1 and HCV IRES elements should assist in defining the critical features of this type of IRES.

  • functional and structural similarities between the internal ribosome entry sites of hepatitis c virus and porcine Teschovirus a picornavirus
    Journal of Virology, 2004
    Co-Authors: Andrey V Pisarev, Louisa S. Chard, Y Kaku, Ivan N. Shatsky, Helen L Johns, Graham J. Belsham
    Abstract:

    Initiation of protein synthesis on picornavirus RNA requires an internal ribosome entry site (IRES). Typically, picornavirus IRES elements contain about 450 nucleotides (nt) and use most of the cellular translation initiation factors. However, it is now shown that just 280 nt of the porcine Teschovirus type 1 Talfan (PTV-1) 5′ untranslated region direct the efficient internal initiation of translation in vitro and within cells. In toeprinting assays, assembly of 48S preinitiation complexes from purified components on the PTV-1 IRES was achieved with just 40S ribosomal subunits plus eIF2 and Met-tRNAiMet. Indeed, a binary complex between 40S subunits and the PTV-1 IRES is formed. Thus, the PTV-1 IRES has properties that are entirely different from other picornavirus IRES elements but highly reminiscent of the hepatitis C virus (HCV) IRES. Comparison between the PTV-1 IRES and HCV IRES elements revealed islands of high sequence identity that occur in regions critical for the interactions of the HCV IRES with the 40S ribosomal subunit and eIF3. Thus, there is significant functional and structural similarity between the IRES elements from the picornavirus PTV-1 and HCV, a flavivirus.

  • unique characteristics of a picornavirus internal ribosome entry site from the porcine Teschovirus 1 talfan
    Journal of Virology, 2002
    Co-Authors: Y Kaku, Louisa S. Chard, Toru Inoue, Graham J. Belsham
    Abstract:

    The Teschoviruses constitute a recently defined picornavirus genus. Most of the genome sequence of the porcine Teschovirus-1 (PTV) Talfan and several other strains is known. We now demonstrate that initiation of protein synthesis occurs at nucleotide (nt) 412 on the PTV Talfan RNA and that nt 1 to 405 contains an internal ribosome entry site (IRES) that functions efficiently in vitro and within mammalian cells. In comparison with other picornavirus IRES elements, the PTV IRES is relatively short and lacks a significant polypyrimidine tract near the 3′ end. Expression of an enterovirus 2A protease, which induces cleavage of eIF4G within the translation initiation complex eIF4F, has little effect on the PTV IRES activity within BHK cells. The PTV IRES has a unique set of properties and represents a new class of picornavirus IRES element.

Liu Di - One of the best experts on this subject based on the ideXlab platform.

  • Immunogenicity of porcine Teschovirus Swine/CH/IMH/03
    Chinese Journal of Preventive Veterinary Medicine, 2020
    Co-Authors: Liu Di
    Abstract:

    To investigate the immunogenicity of porcine Teschovirus(PTV) Swine/CH/IMH/03 isolate,the virus isolate was inactivated and emulsified with aluminum hydroxide or Montanide ISA 50V2 adjuvant to prepare the oil adjuvant vaccines.The antibodies against PTV were detected in piglets immunized with the oil adjuvant vaccines once or twice via intramuscular injection,respectively.Antibody titrations results showed that inactivated PTV Swine/CH/IMH/03 was able to efficiently induce antibody response in experimental animals.The antibodies of immunized group were significantly higher than of unimmunized group.Immunization of inactivated PTV emulsified with aluminum adjuvant had a better effect than that of Montanide ISA 50V2 adjuvant.However,it was no significant difference for once or twice immunization.In conclusion,the study of PTV Swine/CH/IMH/03 immunogenicity provides technical support for porcine teschen disease prevention.

  • Biological characteristics and pathogenicity of porcine Teschovirus Swine/CH/IMH/03 isolate
    Chinese Journal of Preventive Veterinary Medicine, 2020
    Co-Authors: Liu Di
    Abstract:

    To determine the permissive cell lines for porcine Teschovirus(PTV) isolate of Swine/CH/IMH/03 and evaluate the pathogenicity of the virus,the virus was inoculated to difference cell lines for virus replication tests.The results showed virus was able to efficiently replicate in IB-RS-2 and PK-15,which were identified by cytopathic effect,electron microscopy observation in the cell lines and PCR amplification of the virus 5'UTR.Furthermore,the pathogenicity test result indicated that the PTV Swine/CH/IMH/03 was highly pathogenic to piglets,which caused pathological lesions including brain hemorrhage,pneumorrhagia,splenorrhagia,and enterorrhagia,and the histopathology changes associated with glial cell infiltration in brain parenchyma,renal interstitial vascular congestion,interstitial pneumonia,reduced splenic lymphocytes,and small intestine hemorrhage and lymphocyte infiltration.

  • immunogenicity of porcine Teschovirus swine ch imh 03
    Chinese Journal of Preventive Veterinary Medicine, 2012
    Co-Authors: Liu Di
    Abstract:

    To investigate the immunogenicity of porcine Teschovirus(PTV) Swine/CH/IMH/03 isolate,the virus isolate was inactivated and emulsified with aluminum hydroxide or Montanide ISA 50V2 adjuvant to prepare the oil adjuvant vaccines.The antibodies against PTV were detected in piglets immunized with the oil adjuvant vaccines once or twice via intramuscular injection,respectively.Antibody titrations results showed that inactivated PTV Swine/CH/IMH/03 was able to efficiently induce antibody response in experimental animals.The antibodies of immunized group were significantly higher than of unimmunized group.Immunization of inactivated PTV emulsified with aluminum adjuvant had a better effect than that of Montanide ISA 50V2 adjuvant.However,it was no significant difference for once or twice immunization.In conclusion,the study of PTV Swine/CH/IMH/03 immunogenicity provides technical support for porcine teschen disease prevention.

  • biological characteristics and pathogenicity of porcine Teschovirus swine ch imh 03 isolate
    Chinese Journal of Preventive Veterinary Medicine, 2012
    Co-Authors: Liu Di
    Abstract:

    To determine the permissive cell lines for porcine Teschovirus(PTV) isolate of Swine/CH/IMH/03 and evaluate the pathogenicity of the virus,the virus was inoculated to difference cell lines for virus replication tests.The results showed virus was able to efficiently replicate in IB-RS-2 and PK-15,which were identified by cytopathic effect,electron microscopy observation in the cell lines and PCR amplification of the virus 5'UTR.Furthermore,the pathogenicity test result indicated that the PTV Swine/CH/IMH/03 was highly pathogenic to piglets,which caused pathological lesions including brain hemorrhage,pneumorrhagia,splenorrhagia,and enterorrhagia,and the histopathology changes associated with glial cell infiltration in brain parenchyma,renal interstitial vascular congestion,interstitial pneumonia,reduced splenic lymphocytes,and small intestine hemorrhage and lymphocyte infiltration.

Feng Li - One of the best experts on this subject based on the ideXlab platform.

  • Expression of porcine Teschovirus swine/CH/IMH/03 strain VP1 protein in Escherichia coli and analysis of its reactinogenicity.
    Chinese Veterinary Science, 2020
    Co-Authors: Shen Shichuan, Shi Hongyan, Chen Jianfei, Sun Dongbo, Wang Chengbao, Fan Xiuping, Chen Xiaojin, Lümaojie, Feng Li
    Abstract:

    One pair of primers was designed according to the published sequences of VP1 gene of porcine Teschovirus Swine/CH/IMH/03 strain.The VP1 gene was amplified by RT-PCR and cloned into the prokaryotic expression vector pET-32a(+) to construct a recombinant pET-VP1.After sequencing,the recombinant was transformed into Escherichia coli BL21(DE3) competent cells.The transformed bacteria were induced by IPTG to produce a recombinant protein of 45ku of molecular weight.The result showed that 1.0mmol/L IPTG and 6h of induction time were the best conditions for VP1 protein production and the expressed protein accounted for 63.4% of total proteins.The SDS-PAGE analysis and thin-layer scanning of the purified protein showed that the purity of VP1 protein reached 97%.The purified protein could react with the positive serum with the antibody against strain Swine/CH/IMH/03 in a Western-blot test,indicating that the expressed protein possessed strong reactinogenicity.

  • expression of porcine Teschovirus swine ch imh 03 strain vp1 protein in escherichia coli and analysis of its reactinogenicity
    Chinese Veterinary Science, 2009
    Co-Authors: Shen Shichuan, Shi Hongyan, Chen Jianfei, Sun Dongbo, Wang Chengbao, Fan Xiuping, Chen Xiaojin, Feng Li
    Abstract:

    One pair of primers was designed according to the published sequences of VP1 gene of porcine Teschovirus Swine/CH/IMH/03 strain.The VP1 gene was amplified by RT-PCR and cloned into the prokaryotic expression vector pET-32a(+) to construct a recombinant pET-VP1.After sequencing,the recombinant was transformed into Escherichia coli BL21(DE3) competent cells.The transformed bacteria were induced by IPTG to produce a recombinant protein of 45ku of molecular weight.The result showed that 1.0mmol/L IPTG and 6h of induction time were the best conditions for VP1 protein production and the expressed protein accounted for 63.4% of total proteins.The SDS-PAGE analysis and thin-layer scanning of the purified protein showed that the purity of VP1 protein reached 97%.The purified protein could react with the positive serum with the antibody against strain Swine/CH/IMH/03 in a Western-blot test,indicating that the expressed protein possessed strong reactinogenicity.

  • advance in molecular biology of porcine Teschovirus
    Progress in Veterinary Medicine, 2008
    Co-Authors: Feng Li
    Abstract:

    Porcine Teschovirus(PTV)was described as causative agents of severe and mild neurological disorders known as Teschen/Talfan disease,which callsed reproductive failure,pneumonia,diarrhea,and dermal lesions of swine.Nowadays PTV presents subclinical infection,and its pathogenic mechanism,molecular mechanism and interaction with other viruses are not clear.Meanwhile,the study of PTV was little in the world as well as its report in china.The purpose of this article was to review the advances in the study of PTV molecular biology and its prospects.

Y Kaku - One of the best experts on this subject based on the ideXlab platform.

  • pathological changes in pigs experimentally infected with porcine Teschovirus
    Journal of Comparative Pathology, 2009
    Co-Authors: M Yamada, A Miyazaki, Y Yamamoto, K Nakamura, H Tsunemitsu, Y Kaku, M Yoshii, R Kozakura, M Narita
    Abstract:

    Summary Nonsuppurative encephalomyelitis with neurological signs expressed as flaccid paralysis of the hindlimbs was experimentally induced in three-week-old piglets by a single intravenous injection of the Toyama 2002 strain of porcine Teschovirus (PTV) isolated from field pigs in Japan. Lesions characterized by perivascular cuffing of mononuclear cells, focal gliosis, neuronal necrosis and neuronophagia were observed, mainly in the ventral horn of the spinal cord. Nonsuppurative ganglionitis of the spinal ganglion and neuritis of the spinal root were also detected. PTV antigens were detected immunohistochemically and the distribution of these antigens corresponded closely with the distribution of brain lesions. PTV antigens were observed in the ganglion cells before the appearance of the inflammatory changes 3 days post-inoculation (dpi) and were present in the dorsal root and spinal cord on 9 dpi. No lesions of the central nervous system were induced in pigs by oral or intranasal inoculation of this strain of PTV.

  • immunohistochemical distribution of viral antigens in pigs naturally infected with porcine Teschovirus
    Journal of Veterinary Medical Science, 2008
    Co-Authors: Manabu Yamada, Y Kaku, M Yoshii, R Kozakura, Kikuyasu Nakamura, Yu Yamamoto, Ayako Miyazaki, Hiroshi Tsunemitsu, M Narita
    Abstract:

    A distribution of porcine Teschovirus (PTV) antigens in pigs naturally infected with PTV is presented using the method of immunohistochemical examination. In the nervous system, PTV antigens were found in the cytoplasm of neuronal cells and glial cells distributed in the spinal ventral horn and brain stem, and also in the cytoplasm of ganglion cells in the spinal ganglion. No antigens were seen in the cerebral hemisphere. In the nervous system, the distribution of PTV antigens was consistent with lesions characteristic of nonsuppurative encephalomyelitis. In the other examined organ, PTV antigens were observed in bronchiolar epithelial cells in the lung, hepatocytes in the liver, epithelial cells in the tonsils and the myenteric nerve plexus in the small and large intestine.

  • immunohistochemical detection of porcine Teschovirus antigen in the formalin fixed paraffin embedded specimens from pigs experimentally infected with porcine Teschovirus
    Journal of Veterinary Medicine Series A-physiology Pathology Clinical Medicine, 2007
    Co-Authors: M Yamada, A Miyazaki, Y Yamamoto, K Nakamura, H Tsunemitsu, Y Kaku, M Yoshii, M Narita
    Abstract:

    Summary Porcine Teschovirus (PTV) antigens were detected by a streptavidin-biotin complex method in formalin-fixed paraffin-embedded tissues of 3-week-old pigs that had been inoculated intravenously with PTV Talfan strain. PTV antigens were detected in cytoplasm of nerve cells, glial cells and endothelial cells in the cerebellar nuclei, the grey matter of the midbrain, pons and medulla oblongata and the ventral horn of the spinal cord and of ganglion cells in the spinal ganglion corresponding to those lesions characterized as non-suppurative encephalomyelitis and ganglionitis. The results of this study suggest that nerve cells of the brain stem and spinal cord and ganglion cells of the spinal ganglion permit PTV replication and represent the main target cell population of PTV. This is the first study to demonstrate PTV antigen by immunohistochemistry in formalin-fixed paraffin-embedded tissue specimens from pigs infected with PTV.

  • functional analyses of rna structures shared between the internal ribosome entry sites of hepatitis c virus and the picornavirus porcine Teschovirus 1 talfan
    Journal of Virology, 2006
    Co-Authors: Louisa S. Chard, Y Kaku, Barbara Jones, Arabinda Nayak, Graham J. Belsham
    Abstract:

    The internal ribosome entry site (IRES) of porcine Teschovirus 1 (PTV-1), a member of the Picornaviridae family, is quite distinct from other well-characterized picornavirus IRES elements, but it displays functional similarities to the IRES from hepatitis C virus (HCV), a member of the Flaviviridae family. In particular, a dominant negative mutant form of eIF4A does not inhibit the activity of the PTV-1 IRES. Furthermore, there is a high level (ca. 50%) of identity between the PTV-1 and HCV IRES sequences. A secondary-structure model of the whole PTV-1 IRES has been derived which includes a pseudoknot. Validation of specific features within the model has been achieved by mutagenesis and functional assays. The differences and similarities between the PTV-1 and HCV IRES elements should assist in defining the critical features of this type of IRES.

  • functional and structural similarities between the internal ribosome entry sites of hepatitis c virus and porcine Teschovirus a picornavirus
    Journal of Virology, 2004
    Co-Authors: Andrey V Pisarev, Louisa S. Chard, Y Kaku, Ivan N. Shatsky, Helen L Johns, Graham J. Belsham
    Abstract:

    Initiation of protein synthesis on picornavirus RNA requires an internal ribosome entry site (IRES). Typically, picornavirus IRES elements contain about 450 nucleotides (nt) and use most of the cellular translation initiation factors. However, it is now shown that just 280 nt of the porcine Teschovirus type 1 Talfan (PTV-1) 5′ untranslated region direct the efficient internal initiation of translation in vitro and within cells. In toeprinting assays, assembly of 48S preinitiation complexes from purified components on the PTV-1 IRES was achieved with just 40S ribosomal subunits plus eIF2 and Met-tRNAiMet. Indeed, a binary complex between 40S subunits and the PTV-1 IRES is formed. Thus, the PTV-1 IRES has properties that are entirely different from other picornavirus IRES elements but highly reminiscent of the hepatitis C virus (HCV) IRES. Comparison between the PTV-1 IRES and HCV IRES elements revealed islands of high sequence identity that occur in regions critical for the interactions of the HCV IRES with the 40S ribosomal subunit and eIF3. Thus, there is significant functional and structural similarity between the IRES elements from the picornavirus PTV-1 and HCV, a flavivirus.