• Title/Summary/Keyword: antiviral agent

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Elimination of Apple stem grooving virus from 'Mansoo' pear (Pyrus pyrifolia L.) by an antiviral agent combined with shoot tip culture (항바이러스제 처리와 경정배양에 의한 배(Pyrus pyrifolia L.) '만수'의 Apple stem grooving virus 무병화)

  • Cho, Kang Hee;Shin, Juhee;Kim, Dae-Hyun;Park, Seo Jun;Kim, Se Hee;Chun, Jae An;Kim, Mi Young;Han, Jeom Hwa;Lee, Han Chan
    • Journal of Plant Biotechnology
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    • v.43 no.3
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    • pp.391-396
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    • 2016
  • In this study, in vitro-cultured 'Mansoo' pear (Pyrus pyrifolia L.) plants infected with Apple stem grooving virus (ASGV) were used for testing the efficiency of the virus elimination methods. The shoot tips cut from infected plants were treated by thermotherapy ($37^{\circ}C$), cold therapy ($4^{\circ}C$), chemotherapy with ribavirin, and combination of these methods. Treatment periods were 2, 4, and 8 weeks, and concentrations of ribavirin were 20 and $40mg{\cdot}L^{-1}$. The efficiency of ASGV elimination was evaluated by reverse transcription polymerase chain reaction. The shoot survival rate was the highest at 100% after cold therapy, chemotherapy, and combination of two methods, while the rate was the lowest at 33.3% after thermotherapy for 2 weeks. The shoot survival rate after chemotherapy decreased gradually as the treatment period was prolonged. The ASGV elimination rate was the highest at 100% after ribavirin treatment at a concentration of $40mg{\cdot}L^{-1}$ and combination of ribavirin treatment and thermotherapy for 2 weeks, whereas the ASGV elimination rate after cold therapy was the lowest at 16.7%. However, the efficiency of ASGV elimination was enhanced up to 43.3% by the combination of cold therapy and ribavirin treatment. The efficiency of ASGV elimination for all treatments was increased as the treatment period was prolonged. Based on these results, we suggest that ribavirin treatment at a concentration of $20mg{\cdot}L^{-1}$ for 4 weeks or at a concentration of $40mg{\cdot}L^{-1}$ for 2 weeks combined with shoot tip culture was efficient for the elimination of ASGV from pear.

Immunogenicity of Synthetic Peptide Specific for Major Immunogenic Determinat of Hepatitis B Surface Antigen (B형간염(型肝炎) 표면항원(表面抗原)의 주면역원(主免疫原) 결정기(決定基)에 특이(特異)한 합성(合成) Peptide의 면역원성(免疫原性)에 관한 연구(硏究))

  • Shin, Kwang-soon;Han, Su-nam
    • Korean Journal of Veterinary Research
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    • v.25 no.1
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    • pp.7-17
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    • 1985
  • Many investigators have been pursuing various attempts so far to produce hepatitis B surface antigen(HBsAg) vaccines using the techniques such as isolation from plasma of chronic HBsAg carrier, recombinant DNA technique or preparation of synthetic peptides specific for immunogenic determinants. Hepatitis B virus can not grow on any cell lines by the tissue culture technique at the present time. The plasma of chronic HBsAg carrier is expensive and its source is limited. The HBsAg from the recombinant DNA technique gave still very low yield. Another approach, therefore, has been initiated to develop a synthetic hepatitis B virus vaccine. The possible use of several distinct synthetic vaccines in prophylaxis can be facilitated by availability of full synthetic immunogens. Peptides synthesized for potential application as antiviral vaccines have been mostly tested in the form of conjugates with carrier proteins, although the free synthetic peptide can be immunogenic. To understand basic knowledges on the antigenicity and immunogenicity of a synthetic peptide specific for major immunogenic determinant of HBsAg, a nonapeptide, $H_2N^{139}Cys-Thr-Lys-Pro-Thr-Asp-Gly-^{146}Asn-Aba$ COOH, which corresponds to HBsAg amino acid residues 139 to 147, was synthesized by the Merrifield's solid-phase method with a slight modification. The antigenicity and immunogenicity of this specific synthetic peptide were examined comparing with purified plasma-derived natural HBsAg. The results obtained are as follows; 1. The peptide synthesized showed the identical amino acid composition to the theoretical value. The degree of purification and molecular weight were acertained by methods of high performance liquid chromatography and mass spectrometry. 2. Using m-maleimidobenzoyl-N-hydroxysuccinimide ester as a conjugating agent, the synthetic peptide was conjugated to rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin. Their conjugation yields were 8.3, 9.5, 15.8, 13.5, and 11.2%, respectively. 3. The natural HBsAg was purified from plasma of chronic HBsAg carrier. By the electron microscopic observation of the purified natural HBsAg preparation, no Dane particles were observed and the preparation showed negative DNA polymerase activity. 4. Antigenicity of the synthetic peptide and the plasma-derived natural HBsAg was determined by competition radioimmunoassay using $^{125}I$-natural HBsAg. Their 50% inhibitions appeared as $90{\mu}g/ml$ and $0.12{\mu}g/ml$ for the synthetic peptide and the natural HBsAg, respectively. This indicates that the former was about 750-fold less antigenic than the latter. 5. Immunogenicity of the synthetic peptide was determined by administering the peptide-carrier conjugates into rabbits with and without Freund's complete adjuvant. Regardless the carrier proteins and adjuvant, positive immune responses to the synthetic peptide were observed. The higher antibody titers, however, were shown in the groups administered with Freund's complete adjuvant. 6. Immunizing dose 50% in mice of the various peptide-carrier conjugates was 5.47, 6.00, 65.16, 31.25 and $13.03{\mu}g/dose$ for rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin, respectively, while the natural HBsAg showed $0.65{\mu}g/dose$. 7. It was postulated that homologous proteins prefer to heterologous ones as the carriers.

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Inhibitory Effect on Infection of Plant Viruses by Filtrate Powder from Culture Broth of Acinetobacter sp. and Its Mode of Action (Acinetobacter sp. 배양여과액 분말제제의 식물바이러스에 대한 감염억제 효과 및 작용)

  • Kim Mi-Soon;Jung Min-Young;Kim Yun-Sung;Jang Cheol;Hwang In-Cheon;Ryu Ki-Hyun;Choi Jang-Kyung
    • Research in Plant Disease
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    • v.12 no.2
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    • pp.91-98
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    • 2006
  • A filtrate powder, designated as KNF2022, produced from culture broth of Acinetobacter sp. KTB3 was tested for their inhibitory effects on Pepper mild mottle virus (PMMoV) infection to Nicotiana glutinosa or N. tabacum cv. Xanthi nc. When 1/100 dilution with distilled water was treated to the plants and PMMoV was inoculated, the inhibition was estimated to be 94.3 and 95.6%, respectively. The same concentrations of KNF2022 inhibited infections of Pepper mottle virus (PepMoV) and Cucumber mosaic virus (CMV) on Chenopodium amaranticolor by 97.1 and 92.5%, respectively. Duration of inhibitory activity of the filtrate powder from Acinetobacter sp. culture broth against PMMoV infection on N. glutinosa was maintained for 2 days at 80% inhibition level, however, the inhibitory effect was diminished from 4 days after treatment to 50% levels. To evaluate inhibitory effects on systemic host plants of the antiviral agent, symptom developments of PMMoV, PepMoV and CMV on KNF2022-treated pepper plants were investigated. Delayed symptom developments until 10 days after inoculation (DAI) were observed for all the three viruses when the viruses were inoculated individually, and these delayed symptom development effects were maintained until 30 DAI in case of PepMoV. Moreover, PepMoV was not detected by RT-PCR and ELISA until 30 DAI. These delayed symptom development effects were diminished in all combinations of three virus co-inoculations due to synergism of three viruses on symptom developments. Inhibitory effect of KNF2022 was verified under electron microscopic examinations using purified virus preparations. Particles of PMMoV and PepMoV were observed on specimens from 5 min after KNF2022 treatment, and the particle sizes were reached in the range of 200-250 nm and 400-600 nm, respectively. Furthermore, the viral particles were destructed and particle sizes were reached in the range of 100-150 nm and 300-500 nm, respectively, on 60 min after treatments. Reduction of local lesion numbers on N. tabacum cv. Xanthi nc and C. amaranticolor were accompanied with reduction of virus particle sizes. In the case of CMV destructed particle numbers were also increased according to incubation period after KNF2022 treatment and local lesions on C. amaranticolor were reduced.

Inhibition of Lipopolysaccharide-Inducible Nitric Oxide Synthase, $TNF-{\alpha}$, $IL-1{\beta}$ and COX-2 Expression by Flower and Whole Plant of Lonicera japonica (금은화(金銀花) 및 금은화전초(金銀花全草)가 Raw 264.7 cell에서 LPS로 유도된 NO의 생성, iNOS, COX-2 및 cytokine에 미치는 영향)

  • Lee, Dong-Eun;Lee, Jae-Ryung;Kim, Young-Woo;Kwon, Young-Kyu;Byun, Sung-Hui;Shin, Sang-Woo;Suh, Seong-Il;Kwon, Taeg-Kyu;Byun, Joon-Seok;Kim, Sang-Chan
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.2
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    • pp.481-489
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    • 2005
  • Lonicerae Flos has antibacterial effects against Staphylococcus aureus, streptococci, pneumococci, Bacillus dysenterii, Salmonella typhi, and paratyphoid. It is an antiviral agent. The herb has a cytoprotective effect against $CCl_{4}-induced$ hepatic injury. It has antilipemic action, interfering with lipid absorption from the gut. Nowadays this herb is used mainly in the treatment of upper respiratory infections, such as tonsillitis and acute laryngitis. It is also used in the treatment of skin suppurations, such as carbuncles, and to treat viral conjunctivitis, influenza, pneumonia, and mastitis. Lonicerae Flos is dried flower buds of Lonicera japonica, L. hypoglauca, L. confusa, or L. dasystyla. But, for the most part, we use whole plant of Lonicera japonica, as a flower bud of it. And, little is known of the original copy of effects of whole plant, except for the 'Bon-Cho-Gang-Mok', which is written the effects of flower of Lonicera japonica are equal to effects of leaves and branch of it. The present study was conducted to evaluate the effect of flower and whole plant of Lonicera japonica on the regulatory mechanism of cytokines, inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) for the immunological activities in Raw 264.7 cells. In Raw 264.7 cells stimulated with lipopolysaccharide (LPS) to mimic inflammation, flower and whole plant of Lonicera japonica water extracts inhibited nitric oxide production in a dose-dependent manner and abrogated iNOS and COX-2. Flower and whole plant of Lonicera japonica water extract did not affect on cell viability. To investigate the mechanism by which flower and whole plant of Lonicera japonica water extract inhibits iNOS and COX-2 gene expression, we examined the on phosphorylation of inhibitor ${\kappa}B{\alpha}$ and assessed production of $TNF-{\alpha}$, $interleukin-1{\beta}$ $(IL-1{\beta})$ and interleukin-6 (IL-6). Results provided evidence that flower and whole plant of Lonicera japonica inhibited the production of $IL-1{\beta}$, IL-6 and activated the phosphorylation of inhibitor ${\kappa}B{\alpha}$ in Raw 264.7 cells activated with LPS. These findings suggest that flower and whole plant of Lonicera japonica can produce anti-inflammatory effect, which may play a role in adjunctive therapy in Gram-negative bacterial infections, respectively.