• Biotechnology and Bioprocess Engineering:BBE
• /
• v.7 no.6
• /
• pp.340-346
• /
• 2002

The purpose of the present study was to examine the efficacy and mechanism of the PAB (para-amino benzamidine) affinity column chromatography, Viresolve NFP virus filtration, pasteurization (60$\^{C}$ heat treatment for 10 h), and lyophilization steps employed in the manufacture of urokinase from human urine as regards the removal and/or inactivation of the hepatitis A virus (HAV). Samples from the relevant stages of the production process were spiked with HAV and subjected to scale-down processes mimicking the manufacture of urokinase Samples were collected at each step, immediately titrated using a 50% tissue culture infectious dose (TCID$\_$50/), and the virus reduction factors evaluated. PAB chromatography was found to be an effective step for removing HAV with a log reduction factor of 3.24. HAV infectivity was rarely detected in the urokinase fraction, while most of the HAV infectivity was recovered in the unbound and wash fractions. HAV was completely removed during the Viresolve NFP filtration with a log reduction factor of $\geq$ 4.60. Pasteurization was also found to be an effective step in inactivating HAV where the titers were reduced from an initial titer of 7.18 log$\_$10/ TCID$\_$50/ to undetectable levels within 10 h of treatment. The log reduction factor achieved during pasteurization was $\geq$ 4.76. Lyophilization revealed the lowest efficacy for inactivating HAV with a log reduction factor of 1.48. The cumulative log reduction factor was $\geq$ 14.08. Accordingly, these results indicate that the production process for urokinase exhibited a sufficient HAV reducing capacity to achieve a high margin of virus safety.

• Korean journal of applied entomology
• /
• v.28 no.1
• /
• pp.10-15
• /
• 1989

This studies were carried out to selected high pathogenic nuclear polyhedrosis viruses(NPVs) against Pseudaletia(=Leucania) separata for the introduction of microbiol control of the insect NPV in Korea. Among 21 NPVs, Sesamia inferens and 4 P. separata NPV strains were highly pathogenic against P. separata when fed orchard grass leaves smeared virus suspension on the 2nd instar larvae. Three NPV strains (LsNPV-F, LsNPV-G, LsNPV-Y) were more susceptible to the younger instar than the older instar P. separata larvae when fed artificial diet mixed with the virus to the insect.

• Journal of Sericultural and Entomological Science
• /
• v.28 no.1
• /
• pp.54-60
• /
• 1986

Silkworms have been found cross infected with other microsporidia of insects in mulberry trees, forest and fruit gardens. Even the unidentified microsporidian species were not seriously pathogenic to silkworms, the silkworm egg producers lose their profit because of the elimination of eggs laid from moths which are infected with any kind of microsporidian species. Recently, the microsporidian cross infection to silkworm is in tendency of increase and the authors have investigated the field insects to examine the microsporidia. The number of species of insects infected with microsporidia was 10 and they were Boettcherisca peregrina (Robineau-Dewvoidy), Apis melifera linnaeus, Artogenia rapae Linnaeus, Tipula aino Alexander, Altica cacrulescens (Baly), Anomela daimiana Harold, Eilema griseola (Jubner), Rbalbistylun speciosum Uller, Anisodactylus signatus illiger, Oulema oryzae (Kuwayama). From the Boettcherisca peregrina (Rogineau-Desvoidy), three different species of micrsporidia were isolated and the microsporidia isolated from Boettcherisca peregrina (Robineau-Desvoidy), Apis melifera Linnaeus, Artogenia rapae Linnaeus donot have infectivity to silkworm larvae, Bombyx mori L.

• Fisheries and Aquatic Sciences
• /
• v.3 no.3_4
• /
• pp.228-229
• /
• 2000

Trypanosoma sp. (Sarcomastigophora: Kinetoplastida) was found in the blood of the Korean catfish, Silurus asotus, for the first time in Korea. The morphological characteristics of Trypanosoma sp. in the present study were similar with those of T. carassii, T. tincae and T. danilewskyi. However, the free flagellum length of Trypanosoma sp. was obviously shorter than that of those species. The species identification was reserved until elucidating the pleomor-phism according to the phase of infection and the cross infectivity among fish species.

• Korean journal of applied entomology
• /
• v.30 no.3
• /
• pp.212-218
• /
• 1991

Pathogenicity of Spodoptera exigua nuclear polyhedrosis virus (SeMNPV) against the host insect and 8 species of lepidopterous insects and cross infection of baculoviruses to third instar of S. exigua larvae were studied to determine as a biocontrol agent for S. exigua. The median lethal concentrations($LC_{50}$)of the SeMNPV to egg mass was $2.855\times10^5$ PIBs/ml and higher than that to the larvae of S. exigua. Mortality of the SeMNPV in third ins tar larvae was more increased than that in first and fifth instar of S. exigua larvae by 1.16 and 4.11 times, respectively. The median lethal times($LT_{50}$) to $1.56\times10^6$ PIBs/ml was in the range of 4.25 to 5.04 days. Infectivity of the SeMNPV against eight species of lepidopterous insects was showed only in the host insect, S. exigua. Autographa cali/ornica MNPV, Mamestra barassicae MNPV, and Trichoplusia ni MNPV were cross-infected to third instar of S. exigua larvae among ten of baculoviruses tested.

• Journal of Microbiology and Biotechnology
• /
• v.10 no.3
• /
• pp.355-362
• /
• 2000

The Herpes simplex virus type 1 (HSV-1) glycoprotein B (gB) gene in the pHLA-21 plasmid was inserted into a baculovirus (Hyphantria cunea nuclear polyhedrosis virus) expression vector (lacZ-HcNPV) to construct a recombinant virus gB-HcNPV expressing gB. Spodoptera frugiperda cells infected with this recombinant virus synthesized and processed gB of approximately 120 kDa, which cross-reacted with the monoclonal antibody to gB. The recombinant gB was identified on the membrane of the insect cells using an immunofluorescence assay. Antibodies to this recombinant raised in mice recognize the viral gB and neutralized the infectivity of the HSV-1 in vitro. These results show that the gB gene has the potential to be expressed in insect cells. They also demonstrate that it is possible to produce a mature protein by gene transfer in eukaryotic cells, and indicate the utility of the lacZ-HcNPV-insect cell system for producing and characterizing eukaryotic proteins. Furthermore, the neutralizing antibodies would appear to protect mice against HSV. Accordingly, this particular recombinant protein may be useful in the development of a subunit vaccine.

• Journal of Korean Academy of Nursing
• /
• v.51 no.1
• /
• pp.5-14
• /
• 2021

Purpose: This study aimed to investigate sub-health status (SHS) of people living in China during the Coronavirus disease 2019 (COVID-19) COVID-19 pandemic. COVID-19 is a severe acute respiratory syndrome coronavirus (SARS-CoV) infection-induced acute infectious disease, which is featured by universal susceptibility and strong infectivity, and SHS (a status of low quality health) refers to a status of low-quality health. COVID-19 has gradually developed into a global pandemic, making the public in a high stress situation in physiological, psychological and social states in the short term. Methods: From March 6 to 11, 2020, a large-scale cross-sectional survey was conducted by convenient sampling, and SHS assessment scale was used in the questionnaire. The ordinal logistic regression analysis was used to identify the factors affecting SHS. Results: In this study, 17,078 questionnaires were delivered with 16,820 effective questionnaires collected, and 10,715 subjects (63.7%) were found with SHS, with moderate SHS primarily. Physiological sub-scale scored the highest, followed by psychological and social sub-scales. Ordinal logistic regression analysis indicated that man, only-child, workers and farmers were risk factors of SHS. Protective factors of SHS included living in rural areas and townships, laid-off retirees and education degree. Conclusion: It shows many people in China place in a poor health status during COVID-19 pandemic. It is necessary that relevant departments pay more attention to people with poor health such as men, only-child, urban people, workers and farmers, and groups with high education degree during and after pandemic stabilization.

• Journal of Sericultural and Entomological Science
• /
• v.34 no.2
• /
• pp.26-31
• /
• 1992

Flacherie virus (FV) and Densonucleosis virus (DNV) of the silkworm, Bombyx mori, which give the most severest damage to the silk production in korea, were fed on the mulberry wild silkworm, Bombyx mori mandarina, the mulberry pyralid, Gryphodes phyloalis, and the American fall webworm, Hypantria cunea, to investigate cross infectivity by serological and histopathological at observation. By the Ouchterlony's double difusion test the mulberry wild silkworm was infected with both FV and DNV type 1 (DNV-1) and the mulberry pyralid with DNV-1, so those were confirmed the cross infection. But the American fall webworm was not recognized the cross infection by the same method. The infection and multiplication of the FV in the mulberry wild silkworm was observed in the cytoplasm of the goblet cell with the appearance of the virus-specific vesicle. In DNV-1 infection to the mulberry wild silkworm and the mulberry pyralid, the nuclei of columnar cell in the midgut of both insects was hypertrophied and the nuclei of midgut cell of the mulberry pyralid positively stained with the feulgen stain. Multiplication of DNV-1 in the midgut cell of the mulberry wild silkworm was replicated in two different patterens as linear arrays and large masses, while that of DNV-1 in the muberry pyralid was multiplied as virus masses in several portion of the nuclei of the midgut cell.

• Korean Journal of Veterinary Research
• /
• v.43 no.2
• /
• pp.239-246
• /
• 2003

Polymerase chain reaction (PCR) was evaluated for the early detection of Aujeszky's disease virus (ADV) DNA from virus-infected cell cultures. For the purposes, the Korean ADV NYJ1-87 was propagated in swine kidney (SK) cells and subjected to the amplification of DNA (217 bp) by PCR using sense and antisense primers specific to gp50 gene of the ADV. In detection of cell-associated viral DNA, reliable PCR conditions were determined as 30 cycles of reaction consisting 1 minute each of denaturation at $94^{\circ}C$, annealing at $55^{\circ}C$ and polymerization at $72^{\circ}C$. The PCR encountered best results with reagent mixtures of $50{\mu}l$ containing $200{\mu}M$ dNTPs, $0.2{\mu}M$ each sense and antisense primers, 1 mM $MgCl_2$ and 10% (v/v) template DNA in the final concentrations. ADV-specific DNAs were detected as early as 6, 6, and 9 hours post-infection, respectively, from lysates of the SK cells infected with ADV of $10^3$, $10^2$ and $10^1\;TCID_{50}/ml$ by this condition. In culture supernatant, the DNAs were detected from ADV of as low infectivity as $10^ {-3}\;TCID_{50}/ml$ by the reduced reagent concentrations and 30 cycles of 1 minute each of denaturation at $94^{\circ}C$ and annealing at $55^{\circ}C$, and 2 minutes of polymerization at $72^{\circ}C$. The lowest amount of detectable ADV DNA was 1 fg. In conclusion, the PCR condition established in the present study was recognized as a feasible alternative to time-consuming procedures in isolation and characterization of the virus.

• Korean journal of applied entomology
• /
• v.34 no.3
• /
• pp.218-223
• /
• 1995

A nuclear polyhedrosis virus isolated from the oriental tobacco budworm larvae, Helicoverpa assulta (Guenee) was characterized by electron microscopy, SDS-PAGE, restriction endonuclease analysis and cross infectivity. The shape of a polyhedron was $1.0\mu\textrm{m}$ in average with icosahdral outline, and the virus particle was $65nm\times300nm$ in average with rod-shape. The nuclear polyhedrosis virus was contained a single nucleocapsid within a viral envelope embedded in a polyhedron. The polyhedral protein was composed of a single polypeptide with a M.W. of 31 Kd. The genome size of the virus by restriction endonuclease analysis was about 120 Kb. Among several nuclear polyhedrosis viruses, the nuclear polyhedrosis virus from Helicoverpa assulta (HaNPV) and Autographa california nuclear polyhedrosis virus (AcNPV) were infected the oriental tobacco budworm larvae.