• Research in Plant Disease
• /
• v.13 no.1
• /
• pp.30-33
• /
• 2007

One hundred and eighty-six leaves of soybean cv. Seokryangputkong that showed mild mosaic symptoms were collected randomly and ELISA tests were conducted with those leaf samples to screen the presence of Cowpea mosaic virus (CPMV). Ninety-three out of 186 samples reacted positively to CPMV, but those samples did negatively to Soybean mosaic virus (SMV). At least, 55 leaf samples revealed higher values than that of positive control. The results strongly confirmed that CPMV occurred severely in soybean cv. Seokryangputkong. However, a question is raised on the primary reservoir and vector for transmission of this virus. Since the farmer changes seeds every year, seed transmission is excluded. The virus was also purified, the analysis of coat protein conformed the virus of cowpea mosaic virus and UV absorption pattern confirmed that the causal virus of mosaic disease in soybean putkong was cowpea mosaic virus.

• Korean Journal of Veterinary Research
• /
• v.22 no.1
• /
• pp.23-26
• /
• 1982

한건(韓件) 및 유우(乳牛)의 우백혈병(牛白血病) 바이러스의 감염상태(感染狀態)와 목장(牧場)의 오염상황(汚染狀況) 등 역학적(疫學的)인 연구(硏究)를 위하여, 경북지방(慶北地方)의 14개목장(個牧場) 유우(乳牛) 106두(頭)와 대구(大邱) 도축장(屠畜場)에서 한우(韓牛) 699두(頭)의 혈청항체(血淸抗體)를 조사(調査)하였다. 우백혈병(牛白血病) 바이러스의 바이러스의 본(本) 바이러스의 단백항원(蛋白抗原)(P)과 당단백항원(糖蛋白抗原)(gp)를 가지고 한천(寒天) Gel 내침강반응(內沈降反應)(ID)을 실시하였고 그 결과(結果)는 다음과 같다. 1. 유우(乳牛) 106두(頭)에 있어서 gp-ID 양성(陽性)인 것은 30두(頭)(28.3%)이었고, 14개목장(個牧場)중 12개(個) 목장(牧場)이 본(本) 바이러스에 오염(汚染)되어 있었으며, 목장별(牧場別) 오염률(汚染率)은 12.5에서 60%로 높은 감염률(感染率)을 나타내었다. 2. 한건(韓件) 699두(頭)에서 gp-ID에 양성(陽性)인 것은 17두(頭)(2.4%)로 낮았다. 3. gp-ID 양성혈청(陽性血淸) 47례(例)중 P 항원(抗原)을 가지고 있는 것은 유우(乳牛) 5두(頭)에서만 인정(認定)되었다.

• The Journal of the Korean Society for Microbiology
• /
• v.14 no.1
• /
• pp.79-87
• /
• 1979

The immunosuppressive activity of newcastle disease virus(NDV) and some possible role of interferon(C-IF) in viral suppression of immune response were evaluated by SRBC-induced delayed-type hypersensitivity(DTH), rosette formation in spleen cells, number of lymphocytes in peripheral blood, hemagglutinin and hemolysin response to SRBC in ICR mice sensitized with SRBC. When NDV was inoculated before or after sensitization of mouse with SRBC, virus caused a marked inhibition of DTH, and its depressive effect was dependent on the time of virus inoculation in relation to SRBC sensitization or challenge. Rosette formation of spleen cells was significantly reduced by NDV infection. The degree of the depression of rosette formation was more prominent in mice inoculated before sensitization than after sensitization and could be related to the amount of serum interferon induced by the virus. Humoral response to SRBC of virus infected mouse was significantly depressed when NDV was inoculated 24 or 48 hours before sensitization. However, there was no difference in the response when the virus was inoculated 9 hour before and at the same time of sensitization or even after that. Lymphocytes in peripheral blood of mice were markedly diminished in numbers when NDV was inoculated 48 and 24 hour before sensitization with SRBC, but they were slightly augmented when the virus was inoculated 9 hour before and at the same time of sensitization. When UV-inactivated or heat-inactivated NDV was injected to the mouse at the same time of sensitization with SRBC, DTH and rosette formation of spleen cells were slightly depressed. DTH and rosette formation in mice treated with crude-IF were generally depressed as com pared with those of control mice. These studies suggest that the NDV causes a significant depression of cell-mediated immunity, whereas the humoral immune response is not inhibited markedly, and that the depression of immune response by NDV infection may be caused by interferon produced by NDV and direct viral activity.

• KSBB Journal
• /
• v.16 no.3
• /
• pp.274-280
• /
• 2001

A serum-free media for CRIP/MFG-LacZ retrovirus production was developed and applied to continuous packed-bed culture system. The serum-free media developed by fractional factorial design contains indulin ($10\mug/mL$), transferrin ($5\mug/mL$), BSA (4 mg/mL), EGF (25 ng/mL), and linoleic acid ($10\mug/mL$). Operation of continuous packed-bed reactor using Fibra-cel enabled the packging cell to stably maintain retrovirus titer for about 1 week. The optimal operation conditions for dilution rate and temperature were 0.67(h(sup)-1) and $32^{circ}C$, respectively. Using this media, the retrovirus titer(cfu/mL) in the packed continuous culture was about 50% that of continuous culture with serum containing DMEM media.

• Korean Journal of Microbiology
• /
• v.37 no.4
• /
• pp.289-293
• /
• 2001

Incidence of infectious viruses is ensuing throughout the world and threatening the health of children as well as adults. The outbreaks of viral diseases of alimentary tract in Pusan from 1998 to 2000 were detected. Viruses were isolated from stool specimens, cerebrospinal fluid and throat swabs from suspicious patients and confirmed by cell culture, latex agglutination test, indirect immunofluorescent test and electron microscopic observation. The average isolation rate was 12.5% from the suspected specimens. From this work, 2 cases of enteric adenoviruses, 23 cases of echovirus, 31 cases of coxsackivirus 36 cases of rotavirus, 45 cases of SRSV, and 7 cases of poliovirus were detected. The major serotypes of coxsackievirus were B2, B3, B4, B6 and echovirus of serotypes 6, 9, 11, 25, and 30 were examined. Two cases of enteric adenovirus type 41 were also confirmed. The incidence of SRSV was mostly concentrated between December through following March, April through October with echovirus and coxsackievirus, and January through April with rotavirus, respectively. Electron micrograph of negative-stained viruses showed typical appearance with 30-80 nm in diameter.

• Korean journal of applied entomology
• /
• v.59 no.4
• /
• pp.451-454
• /
• 2020

Sericulture is a main insect industry in Sangju (Kyungpook, Korea). This study reports an occurrence of a viral disease in the sericulture farms in 2020. More than 20% silkworm larvae (Bombyx mori) suffered diarrhea and melted tissues with pathogenic lethality at 4th or 5th instars. PCR diagnosis showed a positive response against B. mori nucleopolyhedrosis virus (BmNPV) infection. Tissue extract of the infected larvae was applied to healthy larvae by a leaf-dipping method and exhibited the same viral symptoms. The viral extract was used to be overlaid on Sf9 cells. The infected Sf9 cells showed polyhedra in the cytoplasm. These results indicate that the silkworm larvae reared in the sericulture farms in Sangju were infected with BmNPV.

• The Journal of Korean Society of Virology
• /
• v.27 no.1
• /
• pp.19-27
• /
• 1997

To develop the polymerase chain reaction (PCR) for the detection of type D simian retrovirus (SRV) infection, an oligonucleotide primer pair was designed to hybridize to the sequences within env gene of SRV subtype 1 (SRV-1). The 3' proximal env sequences annealing to the primers had been rather conserved among three different subtypes of SRV, SRV-1, SRV-2, and SRV-3 (Mason-Pfizer Monkey Virus: MPMV). The PCR using the primer pair targeting an env region successfully detected and amplified all three subtypes of SRV with excellent specificity after single round of reaction. The tests with peripheral blood mononuclear cells infected either with simian immunodeficiency virus or simian T-Iymphotropic virus type 1, major immunosuppressive viral agents together with SRV in simian, verified the specificity of the PCR by excluding any cross reactivity. Semiquantitative titration PCR, amplifying serially diluted plasmid DNA of each subtype, was performed to evaluate sensitivity limits of the reaction. Based on molecular weight of each cloned SRV genome, the PCR should be able to detect one SRV-infected cell per more than $5-7{\times}10^4$ uninfected cells after simple ethidium bromide staining of resulting products. The PCR must be very efficient screening system with its quickness, certainty, and sensitivity for SRV-infected animals used in human AIDS research model. Second round amplification of the reaction products from the first PCR, or Southern hybridization by radiolabeled probes shall render to compete its efficacy to ELISA which has been the most sensitive technique to screen SRV infection but with frequent ambiguity problem.

• Korean Journal of Veterinary Research
• /
• v.33 no.2
• /
• pp.269-275
• /
• 1993

Tissue distribution of RHDV in rabbits were examined by immunofluorescence and ABC methods. Tissues including liver, spleen, kidneys, lungs and brain were frozen, cut in a crycut, and fixed in 10% buffered formalin, embedded in paraplast, and cut $5{\sim}7{\mu}m$ thickness. Sections were immunostained Tissue distribution of RHDV in rabbits were examined by immunofluorescence and ABC methods. Tissues including liver, spleen, kidneys, lungs and brain were frozen, cut in a crycut, and fixed in 10% buffered formalin, embedded in paraplast, and cut $5{\sim}7{\mu}m$ thickness. Sections were immunostained with primary antiserum and conjugated second antibodies as recommended by manufacturer. None of the cultures tested showed virus-induced phenomena. Immunoreactive products were commonly found in the liver, in some cases there were also positive staining in the spleen and kidneys. Other organs showed weak or insignificant immunoreactions. By ABC method on the formalin-fixed, paraffin-embedded liver tissues, strong immunoreactivity was found in the periportal triad lesions and peripheral lesions of the hepatic lobules. Immunoreactive products showed diffuse fine granular in the cytoplasm of hepatocytes and sinusoidal cells. In some cells, immunoproducts marginate at the periphery of the cells. The intensive staining of the cytoplasm of infected cells allowed their exact differentiation from surrounding uninfected cells. The positive area involved coincided with histopathological lesion on serial liver sections. In conclusion, liver was proved to be a consistent target organ in RHD, and the immunoperoxidase method in the section of formalin-fixed, paraffin-embedded hepatic tissue could be broadly used for the routine diagnosis of the disease.

• The Science & Technology
• /
• v.2 no.3 s.7
• /
• pp.38-48
• /
• 1969

서론 외부형태 내부형태 발생소장 생활환 날개의 출현기구 성의 결정 개미와의 관계 기주식물의 반응 식물바이러스의 매개 진딧물의 천적 방제법 채집법 표본제작법

• Research in Plant Disease
• /
• v.16 no.3
• /
• pp.238-246
• /
• 2010

In 2006 fall, a preliminary survey of viruses in two important medicinal plants, Cynanchum wilfordii and C. auriculatum, was conducted on the experimental fields at the Agricultural Research and Extension Services of Chungbuk province in Korea. On each experimental fields, percentage of virus infection was ranged from 20 to 80%, and especially an average of disease incidence propagated by roots was twice higher than that by seeds. The various symptoms were observed in Cynanchum spp. plants, such as mosaic, mottle, necrosis, yellowing, chlorotic spot and malformation etc. In electron microscopic examination of crude sap extracts, filamentous rod particles with 390-730 nm were observed in most samples. The virus particles were purified from the leaves of C. wilfordii with typical mosaic symptom, and the viral RNA was extracted from this sample containing 430-845 nm long filamentous rod. To identify the viruses, reverse transcription followed by PCR with random primers was carried out. The putative sequences of P3 and coat protein of potyvirus were obtained. From a BLAST of the two sequences, they showed 26-38% and 62-72% identities to potyviruses, respectively. In SDS-PAGE analysis, the subunit of coat protein was approximately 30.3 kDa, close to the coat protein of potyvirus. In bioassay with 21 species in 7 families, Chenopodium quinoa showed local lesion on inoculated leave and chlorotic spot on upper leave, but the others were not infected. RT-PCR detection using specific primer of C. wilfordii and C. auriculatum samples, all of 24 samples with virus symptom was positive, and five out of seven samples without virus symptom were also positive. On the basis of these data, the virus could be considered as a new member of potyvirus. We suggested that the name of the virus was Keunjorong mosaic virus (KjMV) after the common Korean name of C. wilfordii.