• Journal of Life Science
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• v.24 no.9
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• pp.995-1000
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• 2014

The studies of marine viruses in terms of viral isolation and detection have been limited due to the high mutation rate and genetic diversity of marine viruses. Of the modern methods currently used to detect marine viruses, serological methods based on enzyme-linked immunosorbent assay (ELISA) are the most common. They depend largely on the quality of the antibodies and on highly purified suitable antigens. Recently, a new experimental system for using viral capsid protein as an antigen has been developed using the yeast surface display (YSD) technique. In the present study, the capsid protein gene of the red-spotted grouper nervous necrosis virus (RGNNV) was expressed and purified via YSD and HA-tagging systems, respectively. Two regions of the RGNNV capsid protein gene, RGNNV1 and RGNNV2, were individually synthesized and subcloned into a yeast expression vector, pCTCON. The expressions of each RGNNV capsid protein in the Saccharomyces cerevisiae strain EBY100 were indirectly detected by flow cytometry with fluorescently labeled antibodies, while recognizing the C-terminal c-myc tags encoded by the display vector. The expressed RGNNV capsid proteins were isolated from the yeast surface through the cleavage of the disulfide bond between the Aga1 and Aga2 proteins after ${\beta}$-mercaptoethanol treatment, and they were directly detected by Western blot using anti-HA antibody. These results indicated that YSD and HA-tagging systems could be applicable to the expressions and purification of recombinant RGNNV capsid proteins.

• Plant Biotechnology Reports
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• v.5 no.4
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• pp.331-344
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• 2011

The well-conserved NBS domain of resistance (R) genes cloned from many plants allows the use of a PCR-based approach to isolate resistance gene analogs (RGAs). In this study, we isolated an RGA (CapRGC) from Capsicum annuum "CM334" using a PCR-based approach. This sequence encodes a protein with very high similarity to Rx genes, the Potato Virus X (PVX) R genes from potato. An evolutionary analysis of the CapRGC gene and its homologs retrieved by an extensive search of a Solanaceae database provided evidence that Rx-like genes (eight ESTs or genes that show very high similarity to Rx) appear to have diverged from R1 [an NBS-LRR R gene against late blight (Phytophthora infestans) from potato]-like genes. Structural comparison of the NBS domains of all the homologs in Solanaceae revealed that one novel motif, 14, is specific to the Rx-like genes, and also indicated that several other novel motifs are characteristic of the R1-like genes. Our results suggest that Rx-like genes are ancient but conserved. Furthermore, the novel conserved motifs can provide a basis for biochemical structural. function analysis and be used for degenerate primer design for the isolation of Rx-like sequences in other plant species. Comparative mapping study revealed that the position of CapRGC is syntenic to the locations of Rx and its homolog genes in the potato and tomato, but cosegregation analysis showed that CapRGC may not be the R gene against PVX in pepper. Our results confirm previous observations that the specificity of R genes is not conserved, while the structure and function of R genes are conserved. It appears that CapRGC may function as a resistance gene to another pathogen, such as the nematode to which the structure of CapRGC is most similar.

• Korean Journal of Biological Psychiatry
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• v.7 no.2
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• pp.115-122
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• 2000

The development of molecular biology has brought many changes in psychiatry. Molecular biology makes us possible to know the cause of mental disorders that provide the way to prevent the disorders, and to develop various accurate diagnostic and treatment methods for mental disorders. The author discusses the concept, cause, and treatment of mental disorders in the aspect of molecular biology. Importing the methods of molecular biology into psychiatry, we can anticipate to get a number of the goals of psychiatric genetics, including identification of specific susceptibility genes, clarification of the pathophysiological processes whereby these genes lead to symptoms, establishment of epigenetic factors that interact with these genes to produce disease, validation of nosological boundaries that more closely reflect the actions of these genes, and development of effective preventive and therapeutic interventions based on genetic counseling, gene therapy, and modification of permissive or protective environmental influences. In addition to their capacity to accelerate the discovery of new molecules participating in the nervous system's response to disease or to self-administered drugs, molecular biological strategies can also be used to determine how critical a particular gene product may be in mediating a cellular event with behavioral importance. Molecular biology probably enables us discover the environmental factors of mental disorders and allow rational drug design and gene therapies for mental disorders, by isolation of gene products that facilitate a basic understanding of the pathogenesis of these disorders. A specific genetic linkage may suggest a novel class of drugs that has not yet been tried. With respect to gene therapy, the hypothetical method would use a gene delivery system, most likely a modified virus, to insert a functional copy of a mutant gene into those brain cells that require the gene for normal function.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.1-6
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• 2011

We are aim to evaluate antimicrobial effects of the extract of Galla rhois (GR) on the health status and performance of growing and finishing pigs. This study was conducted on the growing and finishing pigs (n = 200) for 130 days in a swine husbandry. The animals were divided with two groups; GR treated group (n = 100) and commercial diet feeding group (n = 100). GR treated animals had provided with commercial diet adding the extract of GR as 0.2%. During the study period, we compared clinical signs, weight increase rate, diet consumption amount, fecal scores, gross findings, necropsy findings, histopathological findings between the treated group and non treated group. After necropsy, bacteria isolation and PCR analysis were conducted with the clinical samples. As the results of this long-term clinical trial, GR showed the antimicrobial effects on respiratory disease and diarrhea. We were identified that GR had the anti-bacterial and anti-viral effects.

• Journal of Life Science
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• v.19 no.3
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• pp.373-377
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• 2009

Poliovirus, coxsackievirus, and ecovirus isolates from environmental sources were compared with laboratory strains to determine their removal rate in the water treatment process. The recovery efficiencies of poliovirus, coxsackievirus and echovirus using positive strains ranged from $72{\sim}108%$. Regarding virus removal efficiency in water treatment of pilot-plants, about 99% of all of the viruses were removed in the sedimentation step and 100% of viruses were clearly removed through post-ozonation and BAC filteration. Using six cell lines tested viral sensitivity in cell line and showed different sensitivity as viruses. Polioviruses showed higher sensitivity in the BGMK cell line than other cells, and coxsackieviruses were detected in higher level in the BGMK and Vero cell lines. On the other hand, the RD cell line was useful in the isolation of ecoviruses.

• The Plant Pathology Journal
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• v.28 no.1
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• pp.68-74
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• 2012

Biocontrol microbes have mainly been screened among large collections of microorganisms $via.$ nutrient-rich $in$ $vitro$ assays to identify novel and effective isolates. However, thus far, isolates from only a few genera, mainly spore-forming bacilli, have been commercially developed. In order to isolate field-effective biocontrol microbes, we screened for more than 200 oligotrophic bacterial strains, isolated from rhizospheres of various soil samples in Korea, which induced systemic resistance against the soft-rot disease caused by $Pectobacterium$ $carotovorum$ SCC1; we subsequently conducted in $planta$ bioassay screening. Two oligotrophic bacterial strains were selected for induced systemic disease resistance against the $Tobacco$ $Mosaic$ $Virus$ and the gray mold disease caused by $Botrytis$ $cinerea$. The oligotrophic bacterial strains were identified as $Pseudomonas$ $manteilii$ B001 and $Bacillus$ $cereus$ C003 by biochemical analysis and the phylogenetic analysis of the 16S rRNA sequence. These bacterial strains did not exhibit any antifungal activities against plant pathogenic fungi but evidenced several other beneficial biocontrol traits, including phosphate solubilization and gelatin utilization. Collectively, our results indicate that the isolated oligotrophic bacterial strains possessing induced systemic disease resistance could provide useful tools as effective biopesticides and might be successfully used as cost-effective and preventive biocontrol agents in the field.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.643-649
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• 2010

Evaluation of the primary etiologic agents that cause aseptic meningitis outbreaks may provide valuable information regarding the prevention and management of aseptic meningitis. In Korea, an outbreak of aseptic meningitis caused by echovirus type 30 (E30) occurred from May to October in 2008. In order to determine the etiologic agent, CSF and/or stool specimens from 140 children hospitalized for aseptic meningitis at Soonchunhyang University Cheonan Hospital between June and October of 2008 were tested for virus isolation and identification. E30 accounted for 61.7% (37 cases) and echovirus 6 accounted for 21.7% (13 cases) of all the human enteroviruses (HEVs) isolates (60 cases in total). For the molecular characterization of the isolates, the VP1 gene sequence of 18 Korean E30 isolates was compared pairwise using the MegAlign with 34 reference strains from the GenBank database. The pairwise comparison of the nucleotide sequences of the VP1 genes demonstrated that the sequences of the Korean strains differed from those of lineage groups A, B, C, D, E, F, and G. Reconstruction of the phylogenetic tree based on the complete VP1 nucleotide sequences resulted in a monophyletic tree, with eight clustered lineage groups. All Korean isolates were segregated from other lineage groups, thus suggesting that the Korean strains were a distinct lineage of E30, and a probable cause of this outbreak. This manuscript is the first report, to the best of our knowledge, of the molecular characteristics of E30 strains associated with an aseptic meningitis outbreak in Korea, and their respective phylogenetic relationships.

• 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.

• Journal of Preventive Medicine and Public Health
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• v.43 no.3
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• pp.274-278
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• 2010

Objectives: This report describes the results of an investigation on an outbreak of novel influenza A (H1N1) in an English language Institute in Seoul, Korea in May 2009. Methods: In this outbreak, novel influenza A (H1N1) was confirmed in 22 of 91 trainees, trainers and staff members. The trainees and 2 staff members were isolated in an assigned facility and the rest were isolated in their homes after we discovered the first patient with novel influenza A (H1N1). After the isolation, the people in the assigned facility were educated to use N95 respirators and they received oseltamivir for prophylaxis. Results: The initial findings in this study suggest that the symptoms were mild and similar to those of seasonal influenza. The classmates and roommates of the infected patients were more likely to get infected with novel influenza A (H1N1) than the trainees who were not classmates or roommates of the patients (OR: 3.19, 95% Cl=0.91 - 11.11 for classmates and OR: 40.0, 95% Cl=7.4-215.7 for roommates). Conclusions: The public health response seems successful in terms of preventing the spread of this virus into the local community.

• Safety and Health at Work
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• v.13 no.3
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• pp.269-278
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• 2022

Background: PTSD (Post-traumatic stress disorder, PTSD) had a great impact on health care workers during the COVID-19 (Corona Virus Disease 2019, COVID-19). Better knowledge of the prevalence of PTSD and its risk factors is a major public health problem. This study was conducted to assess the prevalence and important risk factors of PTSD among medical staff during the COVID-19. Methods: The databases were searched for studies published during the COVID-19, and a PRISMA (preferred reporting items for systematic review and meta-analysis) compliant systematic review (PROSPERO-CRD 42021278970) was carried out to identify articles from multiple databases reporting the prevalence of PTSD outcomes among medical staff. Proportion random effect analysis, I² statistic, quality assessment, subgroup analysis, and sensitivity analysis were carried out. Results: A total of 28 cross-sectional studies and the PTSD results of doctors and nurses were summarized from 14 and 27 studies: the prevalences were 31% (95% CI [confidence interval, CI]: 21%-40%) and 38% (95% CI: 30%-45%) in doctors and nurses, respectively. The results also showed seven risks (p < 0.05): long working hours, isolation wards, COVID-19 symptoms, nurses, women, fear of infection, and pre-existing mental illness. Two factors were of borderline significance: higher professional titles and married. Conclusion: Health care workers have a higher prevalence of PTSD during COVID-19. Health departments should provide targeted preventive measures for medical staff away from PTSD.