• Journal of Plant Biology
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• v.38 no.3
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• pp.267-274
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• 1995

Based upon the nucleotide sequence of As strain of cucumber mosaic virus (CMV-As0 RNA4, coat protein (CP) gene was selected for the design of oligonucleotide primers of polymerase chain reaction (PCR) for detection and identification of the virus. Reverse transcription and polymerase chain reaction (RT-PCR) was performed with a set of 18-mer CMV CP-specific primers to amplify a 671 bp fragment from crude nucleic acid extracts of virus-infected leaf tissues as well as purified viral RNAs. The minimum concentrations of template viral RNA and crude nucleic acids from infected tobacco tissue required to detect the virus were 1.0 fg and 1:65,536 (w/v), respectively. No PCR product was obtained when potato virus Y-VN RNA or extracts of healthy plants were used as templates in RT-PCR using the same primers. The RT-PCR detected CMV-Y strain as well as CMV-As strain. Restriction analysis of the two individual PCR amplified DNA fragments from CMV-As and CMV-Y strains showed distinct polymorphic patterns. PCR product from CMV-As has a single recognition site for EcoRI and EcoRV, respectively, and the product from CMV-Y has no site for EcoRI or EcoRV but only one site for HindIII. The RT-PCR was able to detect the virus in the tissues of infected pepper, tomato and Chinese cabbage plants.

• Korean Journal of Poultry Science
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• v.12 no.2
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• pp.135-143
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• 1985

A total of eight strains of avian reoviruses were isolated from chickens with arthritis or stunted growth. The isolations were made from broilers or broiler breeders under 12 weeks of age. The viruses had a typical morphology of reoviruses with double capsid layers and 81nm of diameter. In agar gel precipitation tests, the isolates reacted with antisera prepared against S-1133 or R-1 strains of avian reoviruses and cross reacted with S-1133 antigen. They did not agglutinated RBC's from day-old chicks, adult chickens, guinea pigs, and horses. The isolates showed strong resistance against the treatments of chloroform, IUdR, and heat, When infectivities of the viruses were titrated in cell cultures of chicken embryo fibroblast, chicken embryo liver, and Vero cells, similar end points reached four to five days after inoculation, regardless of tell types and virus inoculation time, either inoculated simultaneously at the time of cell seeding or on confluency. Mean times of mortality of chicken embryos inoculated with the isolates via the chorioallantoic membrane ranged from 54 to 59 hours and that of S-1133 strain was 73 hours.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.14 no.2
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• pp.148-154
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• 2011

Purpose: We aimed to study the distribution of rotavirus genotypes (VP7 and VP4) and disease severity of rotavirus gastroenteritis prevalent in our community. Methods: Stool samples were collected from 156 children who were hospitalized with rotavirus gastroenteritis from December 2007 to June 2008. The disease severity of all patients was scored using the Vesikari scale. After extraction of ds-RNA of the rotavirus, cDNA synthesis using reverse transcription and polymerase chain reaction (RT-PCR) and multiplex PCR was performed. Following this, the final identification of genotypes was performed. Results: Of the 156 samples, VP7(G) and VP4(P) genotypes were identified in 147 (94.2%) and 140 (89.7%) samples, respectively. G1 (116 of 147 samples; 78.9%) and P[8] (137 of 140 samples; 97.9%) were the most prevalent, respectively. Of the 138 samples identified of combination types of VP7 and VP4, G1P[8] (111 samples; 80.4%) was the most prevalent. Other combination types varied with very low distribution rates. 9.4% of genotypes were not included in the new vaccines. The disease severity score was $11.8{\pm}3.3$ ($mean{\pm}2SD$). The distribution of disease severity was mild or moderate in 37.8% and severe in 62.2% of patients. Conclusion: The most prevalent genotype combination of rotavirus was G1P[8] and genotypes not included in the vaccines represented 9.4% in our community. Disease severity distribution of hospitalized children with rotavirus gastroenteritis was higher in the severe than in the mild and moderate categories.

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.377-382
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• 2009

Viral safety is an important prerequisite for clinical preparations of all biopharmaceuticals derived from plasma, cell lines, or tissues of human or animal origin. To ensure the safety, implementation of multiple viral clearance (inactivation and/or removal) steps has been highly recommended for manufacturing of biopharmaceuticals. Of the possible viral clearance strategies, Ultraviolet-C (UVC) irradiation has been known as an effective viral inactivating method. However it has been dismissed by biopharmaceutical industry as a result of the potential for protein damage and the difficulty in delivering uniform doses. Recently a continuous flow UVC reactor (UVivatec) was developed to provide highly efficient mixing and maximize virus exposure to the UV light. In order to investigate the effectiveness of UVivatec to inactivate viruses without causing significant protein damage, the feasibility of the UVC irradiation process was studied with a commercial therapeutic protein. Recovery yield in the optimized condition of $3,000\;J/m^2$ irradiation was more than 98%. The efficacy and robustness of the UVC reactor was evaluated with regard to the inactivation of human immunodeficiency virus (HIV), hepatitis A virus (HAV), bovine herpes virus (BHV), bovine viral diarrhea virus (BVDV), porcine parvovirus (PPV), bovine parvovirus (BPV), minute virus of mice (MVM), reovirus type 3 (REO), and bovine parainfluenza virus type 3 (BPIV). Non enveloped viruses (HAV, PPV, BPV, MVM, and REO) were completely inactivated to undetectable levels by $3,000\;J/m^2$ irradiation. Enveloped viruses such as HIV, BVDV, and BPIV were completely inactivated to undetectable levels. However BHV was incompletely inactivated with slight residual infectivity remaining even after $3,000\;J/m^2$ irradiation. The log reduction factors achieved by UVC irradiation were ${\geq}3.89$ for HIV, ${\geq}5.27$ for HAV, 5.29 for BHV, ${\geq}5.96$ for BVDV, ${\geq}4.37$ for PPV, ${\geq}3.55$ for BPV, ${\geq}3.51$ for MVM, ${\geq}4.20$ for REO, and ${\geq}4.15$ for BPIV. These results indicate that UVC irradiation using UVivatec was very effective and robust in inactivating all the viruses tested.

• Journal of Yeungnam Medical Science
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• v.25 no.1
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• pp.41-49
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• 2008

Background : The central physiological derangement of hemorrhagic fever with renal syndrome (HFRS) caused by hantaan virus (HTNV) is a vascular dysfunction, manifested by hemorrhage, impaired vascular tone and increased vascular permeability. Platelet activating factor (PAF), whose actions are mediated through a specific receptor, is a potent bioactive lipid. PAF has diverse biological functions in the vascular system, such as increasing vascular permeability, adhesion of leukocytes to the endothelium and reduction of cardiac output, which result in hypotension and shock. The goal of the present study was to investigate whether PAF is involved in the pathogenesis of HFRS. For this purpose, we evaluated the effect of HTNV on the expression of PAF receptor (PAF-R) and on the activity of PAF-acetylhydrolase (PAF-AH) instead of PAF because PAF is rapidly degraded by PAF-AH in vivo. Materials and methods : To evaluate the expression of PAF-R, we performed reverse-transcription PCR, western blot and FACS analyses using HTNV-infected human umbilical vein endothelial cells (HUVECs) and non-infected (control) HUVECs. In addition, we measured the activity of plasma PAF-AH in HFRS patients and normal healthy persons. Results : The mRNA and protein expression of PAF-R was increased in HTNV-infected HUVECs compared with control HUVECs at 2 and 3 days post-infection (d.p.i.). FACS analysis showed that HTNV induced the surface expression of PAF-R in HUVECs from 2 d.p.i. The activity of plasma PAF-AH was 2.5-fold lower in HFRS patients than in normal healthy persons. Conclusion : Increased PAF-R expression by HTNV might increase the responsiveness to PAF in endothelial cells. Reduced PAF-AH activity in the blood of HFRS patients might delay PAF degradation. These results suggest that changes in PAF-R and PAF-AH by HTNV might influence to PAF activity and might be involved in the vascular dysfunction of HFRS.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.18-23
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• 2012

Highly pathogenic avian influenza virus (HPAIV) is already panzootic in poultry and caused a considerable economic loss in poultry industry. In addition, HPAIV continues to cross species barriers to infect humans and other mammals, often with fatal outcomes. In this study, the virucidal efficacy of Citra-$Kill^{(R)}$ composed to quaternary ammonium chloride and citric acid was investigated against avian influenza H9N2 virus (AIV). A virucidal efficacy was determined with the viability of AIV contacted with the disinfectant in the allantoic membrane of chicken embryos. Citra-$Kill^{(R)}$ and AIV was reacted on the distilled water (DW), hard water (HW) or organic matter suspension (OM) condition. On DW condition, AIV was inactivated with 2,000 fold dilutions of Citra-$Kill^{(R)}$. When the antiviral effect on HW condition was evaluated, the antiviral activity of the disinfectant showed on 1,500 fold dilutions against AIV. With the investigation of the antiviral effect of the disinfectant on OM condition, AIV was inactivated on 500 fold dilutions of Citra-$Kill^{(R)}$. As Citra-$Kill^{(R)}$ possesses virucidal efficacy against AIV, the disinfectant solution can be used to limit the spread of animal viral diseases.

• Korean Journal of Veterinary Research
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• v.20 no.1
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• pp.1-10
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• 1980

매추리 유래 가금 adenovirus인 QBV로 부터 CsCl을 사용한 균질밀도분배원심분리법으로 AAAV의 분리를 시도하였으며, 분리된 바이러스의 순수성을 전자현미경 및 혈청학적인 방법을 통하여 증명하였으며 순수 분리된 AAAV를 항원으로 사용한 혈청반응을 개발하였다. 즉, CsCl의 밀도 1.38 및 $1.42gm/cm^3$의 분획들은 순수한 AAAV이었으며 $1.42gm/cm^3$의 분획은 토끼에서 양성혈청제조용 면역원으로 1.38 및 $1.42gm/cm^3$의 분획은 혈청반응용 표준항원으로 사용하였다. AAAV 표준항원 및 가토 양성혈청계는 MDV, IBDV, ITV 및 "helper"인 가금 adenovirus와의 교차반응이 없었으며 혈청학적인 특이성이 인정되었다. 또한 상기 혈청학적 반응을 이용하여 AAAV의 동정은 물론 AAAV에 대한 닭의 항체검출을 가능하게 하였다.

• Pediatric Infection and Vaccine
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• v.18 no.1
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• pp.61-67
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• 2011

Purpose : This study was performed to investigate the epidemiologic characteristics of human bocavirus (HBoV)-associated lower respiratory tract infections (LRTIs) in children. Methods : Nasopharyngeal aspirate samples were obtained from 658 children who had been hospitalized for LRTIs in Seoul National University (SNU) Children's Hospital and SNU Bundang Hospital from March 2000 to September 2005. Multiplex RT-PCR was performed to detect 11 respiratory viruses including respiratory syncytial virus, adenovirus, rhinovirus, parainfluenza viruses 1 and 3, influenza viruses A and B, human metapneumovirus, HBoV, human coronavirus (HCoV) OC43/ 229E, and HCoV-NL63. Clinical data were reviewed retrospectively. Results : Overall, respiratory viruses were detected in 325 (49.4%) among 658 patients. HBoV was detected in 62 cases (9.4%) and was responsible for 19.1% of virus-positive cases. HBoV was prevalent among infants and young children aged from 3 months to 5 years with the mean age of 25.3 months. Co-detection of HBoV and other respiratory viruses was observed in 37.1% which is significantly higher than average co-detection rate (12.3%) among overall virus-positive cases (P=0.000). HBoV was identified mainly in late spring and early summer from May to July. Conclusion : This study describes epidemiologic features of HBoV in Korean children compared with those associated with other respiratory viruses. HBoV was prevalent among LRTIs in childhood, especially in late spring and early summer season in Korea.

• Korean journal of applied entomology
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• v.17 no.3 s.36
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• pp.131-138
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• 1978

A virus named Cymbidium mild mosaic virus(Cy MMV), was mechanically transmitted to Chenopodium amaranticolor from the leaves of Cymbidium with mild mosaic symptoms. The virus was cultured in C. amaranticolor, in which it produced local chlorotic and ring spots, followed by systemic vein clearing with distortion. CyMMV infected 7 out of 35 species of plants. In C. amaranticolor juice infectivity was lost by heating at $90^{\circ}C$ for 10 miuntes, and by aging at$20^{\circ}C$ for 60 days, and by diluting at $10^{-6}$ when bioassayed on C. amaranticolor. CyMMV was not transmitted by Myzus persicae. The virus was purified after clarification of homogenized C. amaranticolor leaf tissues with chloroform, by differential centrifugation followed by sucrose density gradient centrifugation. Electron microscopic examination of purified preparation showed spherical particles of 28nm in diameter. The UV absorption spectrum of purified preparation was typical of u nucleoprotein (max. at 261nm. min. at 243nm), and showed 260/280=1.72 and max/min=1.26. The value of the sedimentation coefficient of the virus was S20.w=126. In gel-diffusion tests, CyMMV antiserum reacted with CarMV, but not with any of four other viruses (BBWV, CRSV, CMV, TBRV) having similar particles and properties in vitro. In ultra-thin sections of CyMMV infected tissues, a large number of virus particles were found in the cytoplasm of mesophyll cells and in xylem vessels.

• Journal of the Korean Society for information Management
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• v.38 no.4
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• pp.113-128
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• 2021

In this study, we aimed to understand the public opinion on COVID-19 vaccine. To achieve the goal, we analyzed COVID-19 vaccine-related Twitter posts. 45,413 tweets posted from March 16, 2020 to March 15, 2021 including COVID-19 vaccine names as keywords were collected. The 12 vaccine names used for data collection included 'Pfizer', 'AstraZeneca', 'Modena', 'Jansen', 'NovaVax', 'Sinopharm', 'SinoVac', 'Sputnik V', 'Bharat', 'KhanSino', 'Chumakov', and 'VECTOR' in the order of the number of collected posts. The collected posts were analyzed manually and automatedly through keyword analysis, sentiment analysis, and topic modeling to understand the opinions for the investigated vaccines. According to the results, there were generally more negative posts about vaccines than positive posts. Anxiety about the aftereffects of vaccination and distrust in the efficacy of vaccines were identified as major negative factors for vaccines. On the contrary, the anticipation for the suppression of the spread of coronavirus following vaccination was identified as a positive social factor for vaccines. Different from previous studies that investigated opinions about COVID-19 vaccines through mass media data such as news articles, this study explores opinions of social media users using keyword analysis, sentiment analysis, and topic modeling. In addition, the results of this study can be used by governmental institutions for making policies to promote vaccination reflecting the social atmosphere.