• Korean Journal of Veterinary Service
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• v.14 no.2
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• pp.110-120
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• 1991

28 porcine enteroviruses were isolated from 86 pig-feces of 9 swine farms located in south region, Chung-buk, from March to September 1990. Physico-chemical properties and pathogenicity of isolates were investigated. Results obtained throughout experiments are summarized as follows. According to the age, weanlings(40-90 days), sucklings(10-30 days) and adult pigs(6 months over) showed the isolation rate of 67%. 8% and 4%, respectively. By physico-chemical tests, YD-90/22, YD-90/43 and YD-90/64 strains were found to be ether, chloroform and PH stable. Nucleic acid test suggests the virus to have a DNA genome. Most of the Isolates were not evident of hemagglutinin using erythrocytes from various mammalian & avian. 22 strains among the isolates were shown CPE type I and the remainders were CPE type II. 3 strains among isolates of CPE type I strains were neutralized with high titers to serotype 2 antiserum. In the study on virus growth curve in PK-l5 cells, YD-90/22, YD-90/43 and YD-90/64 strains showed the maximum infectivity titers($10^{6.0}-l0^{6.5} TCID({50}ml$) at 4days post inoculation(PI). When 30 day-old commercial piglets were inoculated only intraoral route with the YD-90/22 strain at $10^{6.0} TCID_{50}ml,$ piglets not showed the symptoms. But piglets inoculated by intramuscle route, intraoral and intramuscle route after pretreat with dexamethasone(2.5mg /kg) for 5 days were shown the symptoms of anorexia, diarrhea, pyrexia and ataxia at 4th-6th days PI. The viral reisolation in the virus-inoculated piglets was examined from feces. The viruses were recovered intermittently from 2nd to 16th day PI and at 4th-6th day PI, all piglets excreted viruses.

• Korean Journal of Veterinary Research
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• v.54 no.2
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• pp.91-99
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• 2014

An antimicrobial susceptibility test was conducted to compare the resistance rates among Campylobacter spp. isolates from dogs (n = 50) raised under diverse conditions and humans (n = 50). More than 60% of Campylobacter (C.) jejuni from dogs and humans showed resistance to nalidixic acid, enrofloxacin and ciprofloxacin. C. jejuni isolates from humans showed higher resistance to tetracycline (83.3%) and ampicillin (91.3%) than those from dogs. None of the C. jejuni or Campylobacter coli isolates from humans or dogs were resistant to erythromycin. Overall, 85% of Campylobacter spp. isolates showed a multidrug resistant phenotype. Nucleotide sequencing analysis of the gryA gene showed that 100% of $NA^R/CIP^R$ C. jejuni isolates from dogs and humans had the Thr-$86^{th}$-Ile mutation, which is associated with fluoroquinolone resistance. flaA PCR restriction fragment length polymorphism (RFLP) typing to differentiate the isolates below the species level revealed 12 different clusters out of 73 strains. The human isolates belonged to eight different RFLP clusters, while five clusters contained dog and human isolates.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.205-212
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• 2001

One of the important characteristics of biological systems os their ability to change im-portant properties in response to small environmental signals. The molecular mechanisms that biological molecules utilize to sense and respond provide interesting models for the development of "smart" polymeric biomaterials with biomimetic properties. An important example of this is the protein coat of viruses, which contains peptide units that facilitate the trafficking of the virus into the cell via endocytosis, then out of the endosome into the cytoplasm, and from there into the nucleus, We have designed a family of synthetic polymers whose compositions have been de-signed to mimic specific peptides on viral coats that facilitate endosomal escape. Our biomimetic polymers are responsive to the lowered pH whinin endosomes, leading to distruption of the en-dosomal membrane and release of important biomolecular druges such as DNA, RNA, peptides and proteins to the cytoplasm before they are trafficked to lysosomes and degraded by lysosomal en-zymes. In this article, we review our work on the design, synthesis and action of such smart, pH-sensitive polymers.

• Journal of Aquaculture
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• v.15 no.1
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• pp.7-13
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• 2002

Since 1993, the White Spot Syndrome Virus (WSSV) disease occurred in China among cultured shrimps resulting in mass mortality. Epizootiological surveys undertaken during the outbreak period of 1993-1994 indicated that all stages of Penaeus chinensis, P. japonicus and P. monodon were infected. Consequent to the transport of contaminated shrimp seedlings and seawater, the disease spread all over the farms of China. The disease was more rapidly transmitted at temperatures above $25^{\circ}C$. Challenge experiments showed the causative agent was highly virulent. White spots appeared on the carapace of both span-taneous and experimentally infected shrimps. Moribund shrimps contained turbid hemolymph, hypertrophied Iymphoid organ and a necrotic mid-gut gland. Electron microscopy showed the presence of viral particles in the gills, stomach, lymphoid organ, and epidermal tissue of the infected shrimp. The visions were slightly ovoid with an envelope and averaged 350 $\times$ 150 nm; nucleocapsids measured 375 $\times$ 157 nm. With discontinuous sucrose gradient of 35, 50 and 60% (w/v), the virus was separated from hemolymph of the infected shrimp. The estimated molecular weight of genomic DNA was 237 Kb with EcoR I, 247 Kb with Hind III and 241kb with Pst I. A total of 9 hybridoma colones secreting monoclonal antibodies (MAbs) were produced from mouse myeloma and spleen cells immunized with WSSV. The immunofluorescence assay of gill tissue showed that the MAbs reacted with diseased but not with healthy shrimp. The MAbs belonged to IgGl, IgG2b subclass and IgM class, all with kappa light Immune-electron-microscopy with colloidal gold marker showed the presence of 5 MAbs epitopes on the envelope and one on the capsid of the virus. Baculoviral mid-gut gland necrosis showed the specificity of the MAbs produced. For diagnosis 5 different methods were selected. Using Kimura primers for PCR, or MAbs for immunoblot, ELISA or FAT method, in situ hybridization was carried out to show the gene. All these methods detected WSSV in the organ samples of the diseased shrimp but not in healthy one.

• BMB Reports
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• v.38 no.1
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• pp.41-48
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• 2005

In this study we developed the transposon-mediated shuttle vector 'Hanpvid', which composed of HaNPV (Heliothis armigera nuclear polyhedrosis virus) genomic DNA and a transposon cassette from Bacmid of Bac-to-Bac system. Hanpvid replicates in E. coli in the same way as Bacmid and retains infective function in cotton bollworm cells (Hz-AM1). Using Hanpvid we constructed a recombinant virus, which could infect Hz-AM1 cells and generate recombinant HaNPV (rHa-Bar) containing the barnase gene, a ribonuclease gene from Bacillus amyloliquefaciens. Since the expression vector carrying barnase gene cannot replicate in the absence of barstar, a specific inhibitor of barnase, we constructed a new cotton bollworm cell line (AM1-NB) using the marker rescue method. In AM1-NB barstar was integrated into the cellular chromosome to sustain the replication of rHa-Bar. To screen out recombinant HaNPV for potential use as biopesticide, Hz-AM1 and AM1-NB cell lines were infected with rHa-Bar, respectively. The results obtained indicate that Viral progenies in AM1-NB were 23 and 160 times greater than those in Hz-AM1 48 h and 72 h after infection, respectively. With additional insertion of the polyhedron gene from AcNPV (Autographa californica nuclear polyhedrosis virus) into the Hanpvid genome, rHa-Bar regained the polyhedron phenotype and its pest-killing rate greatly improved. Toxic analysis showed that the lethal dosages ($LD_{50}$) and the lethal time(s) ($LT_{50}$) of rHa-Bar were reduced by 20% and 30%, respectively, compared to wt-HaNPV in the third instar larvae of cotton bollworm. This study shows that in AM1-NB barnase can be effectively produced and used as pest-killing agent for the biological control of cotton pests.

• The Plant Pathology Journal
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• v.20 no.4
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• pp.302-307
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• 2004

Three pairs of specific primers were developed for rapid and precise RT-PCR detection of three seed-transmissible viruses, namely Peanut clump virus (PCV, Pecluvirus), White clover mosaic virus (WCIMV, Potexvirus) and Carrot red leaf virus (CaRLV, Luteovirus). Each primer set was found in conserved region through multiple sequence alignment in the DNAMAN. Total nucleic acids extracted from PCV-, WCMV-, and CaRLV-infected seeds and healthy plants were used for RT-PCR detection using each virus-specific primer, Sizes of PCV, WCIMV, and CaRLV PCR products were 617bp (PCV-uni5 and PCV-uni3 primers), 561bp (WCMV-CP5 and WCMV-CP3 primers), and 626bp (CL1-UP and CL2-DN primers); which corresponded to the target sizes. Nucleotides sequences of each amplified cDNA were confirmed which belonged to the original virus. This study suggests that these virus-specific primer sets can specifically amplify viral sequences in infected seeds. Thus, they can be used for specific detection of three viruses (PCV, WCMV and CaRLV) from imported seed samples for plant quarantine service.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1154-1158
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• 2013

Ganciclovir resistance of human cytomegalovirus is associated with mutations in the viral UL97 gene and poses severe problems for immunocompromised patients. In this study, PCR-based restriction fragment length polymorphism and sequencing analyses detected the UL97 D605E mutation in all five clinical isolates from patients with ganciclovir-resistant human cytomegalovirus infection during prolonged ganciclovir therapy, whereas the M460V mutation was only present in 1 of 5 isolates. On the other hand, the detection rates of the D605E mutation in the stored available DNA samples from the donor and allogeneic stem cell transplantation recipients were 66.7% and 93.7%, respectively, suggesting that the presence of D605E mutation was not associated with the ganciclovir exposure. Although the D605E mutation may not be related to ganciclovir resistance, we suggest that this mutation could be an important molecular marker of human cytomegalovirus evolution in East Asian countries. Moreover, the restriction fragment length polymorphism method using the restriction enzyme HaeIII, which is generally used to detect the UL97 A591V mutation, could also detect the D605E mutation and may therefore be a useful tool for future research on the investigation of UL97 gene mutations.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7433-7438
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• 2013

Aim: To identify new biomarkers for NPC diagnosis with an anti-EBV Western blot test kit. Methods: Serum samples from 64 NPC patients and healthy subjects with four specific VCA-IgA/EA-IgA profiles were tested with an anti-EBV Western blot test kit from EUROIMMUN AG. Proteins were quantified with scores of intensity visually assigned to the protein bands. The markers which showed statistical differences between the NPC and non-NPC subjects were further evaluated in another 32 NPC patients and 32 controls in comparison with established biomarkers including VCA-IgA, EA-IgA, EBV-related protein IgG, and EBV DNA. Results: Among the markers screened, EA-D p45-IgG showed a statistically significant difference (p < 0.05) between NPC and non-NPC subjects with VCA-IgA positivy. In 32 VCA-IgA positive NPC patients and 32 control subjects, the diagnostic accuracy of EA-D p45-IgG was 78.1% with a positive predictive value of 77.8% and a negative predictive value of 78.6%. In the verification experiment, the specificity and sensitivity of EA-D p45-IgG were 75.0% and 90.6 %, respectively. Conclusions: EA-D p45-IgG might be a potential biomarker for NPC diagnosis, especially among VCA-IgA positive subjects.

• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.911-920
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• 2006

[ $CD8^+$ ] T Iymphocytes with the cytotoxic activity and capability to release various cytokines are the major players in immune responses against viral infection and cancer. To identify the proteins specific to resting or activated human CD8$^+$ T cells, human CD8$^+$ T cells were activated with anti-CD3+anti-CD28 mAb in the presence of IL-2. The solubilized proteins from resting and activated human CD8$^+$ T cells were separated by high-resolution two-dimensional polyacrylamide gel electrophoresis, and their proteomes were analyzed. Proteomic analysis of resting and activated T cells resulted in identification of 35 proteins with the altered expression. Mass spectrometry coupled with Profound and SWISS-PROT database analysis revealed that these identified proteins are to be functionally associated with cell proliferation, metabolic pathways, antigen presentation, and intracellular signal transduction pathways. We also identified six unknown proteins predicted from genomic DNA sequences specific to resting or activated CD8$^+$ T cells. Protein network studies and functional characterization of these novel proteins may provide new insight into the signaling transduction pathway of CD8$^+$ T cell activation.

• Microbiology and Biotechnology Letters
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• v.25 no.4
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• pp.359-366
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• 1997

The usefulness of host range expanded recombinant viruses for economical viral insecticide and expression vector system has been studied. Host range expanded recombinant viruses, RecS-B6 and RecB-8, constructed by cotransfection of Bombyx mori nuclear polyhedrosis virus (BmNPV) and Autographa californica NPV (AcNPV), and a host range expanded AcNPV recombinant, Ac-BH, constructed by substitution of the 0.6Kb fragment of the BmNPV helicase gene were compared. The restriction enzyme digestion patterns showed that RecS-B6 and RecB-8 had expanded host ranges by genomic recombination and were more similar to genome of AcNPV than that of BmNPV. SDS-PAGE and PCR analysis showed that the polyhedrin gene of RecS-B6 and RecB-8 was derived from BmNPV genomic DNA. The morphology of polyhedra of recombinant viruses showed a slight difference between the two host cells, Sf and BmN cells, indicating that the morphology of polyhedra was influenced by host cells. The bioassay data for insect larvae showed that Ac-BH, compared to wild type viruses, had superior pathogenicity against Bombyx mori larvae but inferior pathogenicity against Spodoptera exigua larvae. Although the pathogenicity was lower than that of wild type viruses in both larvae, RecS-B6 showed the pathogenicity in both larvae. These results suggested that Ac-BH was a less useful economical insecticide than random genomic recombinant virus RecS-B6.