• Journal of the Korean Society of Visualization
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• v.14 no.3
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• pp.38-45
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• 2016

Separation of particles based on different sizes, detection of pathogenic bacteria and isolation of leukocytes from whole blood are typical applications of spiral or helical microchannels. The present study focuses on developing a CD4+ T-cell counting device for monitoring HIV/AIDS patients with the aid of a helical minichannel used for a sample cartridge. For the experiment, $10{\mu}m$ sized microbeads were used for visualization with a fluorescence imaging system. Alignment of microbeads was investigated in a stationary and spinning sample cartridge filled with glycerol-water mixtures of different densities. The helical minichannel was spun using a DC motor controlled by an Arduino board with a Bluetooth shield. It was found that when the sample cartridge was made stationary, no bead alignment was achieved for a medium with density (0% and 20% glycerol) lower than that of the beads, but when it was spun at 2000-3000 rpm for 1-4 min, an alignment was obtained at the top of the channel facilitating optical detection and enumeration of those microbeads. Since an alignment of microbeads was achieved for a medium with density as that of blood plasma, the same approach can be applied for aligning and counting CD4+ T-lymphocytes in whole blood samples collected from patients.

• The Plant Pathology Journal
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• v.33 no.6
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• pp.543-553
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• 2017

Sesame (Sesamum indicum) is an important oil seed crop of Asia. Yields can be negatively impacted by various factors, including disease, particularly those caused by fungi which create problems in both production and storage. Foliar diseases of sesame such as Alternaria leaf blight may cause significant yield losses, with reductions in plant health and seed quality. The work reported here determined the incidence of Alternaria species infecting sesame seeds grown in the Punjab, Pakistan. A total of 428 Alternaria isolates were obtained from 105 seed samples and grouped into 36 distinct taxonomic groups based on growth pattern and morphological characters. Isolation frequency and relative density of surface sterilized and non-surface sterilized seeds showed that three isolates (A13, A47 and A215) were the most common morphological groups present. These isolates were further identified using sequencing of the Internal Transcribed Spacer (ITS) region of ribosomal DNA (rDNA) and the Alternaria major allergen gene (Alt a 1). Whilst ITS of rDNA did not resolve the isolates into Alternaria species, the Alt a 1 sequences exhibited > 99% homology with Alternaria alternata (KP123850.1) in GenBank accessions. The pathogenicity and virulence of these isolates of Alternaria alternata was confirmed in inoculations of sesame plants resulting in typical symptoms of leaf blight disease. This work confirms the identity of a major source of sesame leaf blight in Pakistan which will aid in formulating effective disease management strategies.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.281-286
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• 2002

Detection of Vibrio vulnificus in fish farm and searching for the bactericidal methods on this bacteria were studied. To detect this microorganism in sea water, mud, fish and mussels, selective isolation methods and detection of vvhA gene were used from January to October,2000. V. vulnificus was detected from May when the water temperature was over $17^{\circ}C$. From June to September, higher than $19^{\circ}C$, this bacteria could be isolated from most of the samples. Freezing and refrigerating did not inhibit the growth of V. vulnificus. Citric acid did not show the bactericidal effect, but more than 500 mg/l of EDTA did. With the aid of UV and photocatalyst, $TiO_{2}$ showed bactericidal effect after 15 minute treatment. Photocatalytic system consisted of glass bead coated with $TiO_{2}$ and UV illumination showed bactericidal effect on V. vulnificus at the turnover rate of 0.2/min.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.819-825
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• 2002

Methanol dehydrogenase (MDH) is a key enzyme in the process of methanol oxidation in methylotrophic bacteria. However, information on MDH genes from genus Methylobacillus is limited. In this study, a 6.5-kb HindIII DNA fragment of Methylobacillus sp. SK-5 chromosomal DNA was isolated from the genomic library of the strain by using a degenerate oligonucleotide probe that was designed based on JV-terminal amino acid sequence of the MDH $\alpha$ subunit purified from the strain. Molecular analysis of the fragment revealed four tightly clustered genes (mxaFJGI) involved in the methanol oxidation. The first and fourth genes were very similar to mxaF (77% identity for nucleotides an 78% identity for amino acids) and mxaF (67% Identity for nucleotides and 68% Identity for amino acids) genes, respectively, from Methylovorus sp. SSI. Genes mxaF and mxaI encode $\alpha$ and $\beta$ subunits of MDH, respectively. The two subunits were identified from purified MDH from Methylobacillus sp. SK-5. A dendrogram constructed by comparison of amino acid sequences of MDH u subunits suggests that MxaF from Methylobacillus sp. SK-5 belongs to a subfamily cluster of MDH u subunits from $\beta$-subgroup Proteobacteria. The subfamily cluster is separated from the other subfamily that consists of $\beta$- and $\gamma$-subgroup Proteobacteria. This study provided information on mn genes from a methylotrophic bacterium in $\beta$-subgroup Proteobacteria, which would aid to better develop a gene probe to detect one-carbon metabolizing bacteria.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.181-186
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• 1996

The present study was conducted to investigate the biochemical and serologic characteristic of Actinobacillus pleuropneumoniae isolated from pneumonic lungs of pigs during the period from January 1992 to April 1993. A pleuropneumoniae was isolated from 17(27.0%) of 63 growing pigs with respiratory signs and 21(6.4%) of 330 pneumonic lungs of slaughtered pigs. The seasonal isolation frequency of A pleuropneumoniae was higher in winter and spring than that in summer or fall. The biochemical and cultural properties of A pleluropneumoniae isolated from the pneumonic lungs of pigs were identical to those of the reference strains used. The isolates were highly susceptible to ampicillin, cephalothin, ceftiofur, ciprofloxacin(MIC : ${\leq}0.39{\mu}g/ml$) and moderately susceptible to amikacin, chloramphenicol, erythromycin, kanamycin, methicillin, penicillin-G, streptomycin(MIC : 0.78~25IU or ${\mu}g/ml$), respectively. Sulfadimethoxine, sulfamerazine, tylosine showed no response to the isolates(MIC : ${\geq}100{\mu}g/ml$). Among the 38 isolates, 21(55.3%) and 13(34.2%) were resistant to oxytetracycline aid lincomydn, respectively(MIC : ${\geq}50IU$ or ${\mu}g/ml$). The majority of 38 A pleuropneumoniae isolates were turned out as serotype 2(47.4%) or serotype 5(54.7%) and the remaining 3 isolates were evenly classified to serotype 7, 10 or 12. It was noted A pleuropneumonine serotype 5 isolates were more resistant to oxytetracycline than serotype 2 isolates.

• Korean Journal of Social Welfare
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• v.64 no.4
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• pp.5-29
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• 2012

This study aimed to express the experiences of the parents who lost their children by suicides in their own words from their own perspectives by van Manen(2000)'s hermeneutic phenomenological approach. The analysis of the words expressed by the research participants led to the following five fundamental themes. These are 'broken heart, sinner's grief, land of exile and time stood still, pains to be comforted, and days ahead with half-stitched wounds'. Several distinctions are found due to cultural differences from Korean parents. First, whereas the Western parents see the cause of their child's suicide as his/her independent issue, the Korean parents blame themselves entirely. This may have stemmed from the overly inter-dependency between the parents and the child. Second, whereas the Western perspective views the suicide as a type of illness from the individual's depression. The Korean perspective views the suicide as a shame that disgraces the parents or the family. This negative social perspective intensifies the self-blame and social isolation. Third, the Westerners recognize the prevention and responsibility of suicide resting with the society and government, but the Korean society recognize suicide as personal or family matter. Based on the finding above, I proposed a number of practical measures to aid the surviving parents who belong to a group with extremely high suicidal rates.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.954-959
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• 2011

There have been a number of studies conducted in order to compare the efficiencies of recovery rates, utilizing different protocols, for the isolation of L. monocytogenes. However, the severity of multiple cell injury has not been included in these studies. In the current study, L. monocytogenes ATCC 19112 was injured by exposure to extreme temperatures ($60^{\circ}C$ and $-20^{\circ}C$) for a one-step injury, and for a two-step injury the cells were transferred directly from a heat treatment to frozen state to induce a severe cell injury (up to 100% injury). The injured cells were then subjected to the US Food and Drug Administration (FDA), the ISO-11290, and the modified United States Department of Agriculture (mUSDA) protocols, and plated on TSAyeast (0.6% yeast), PALCAM agar, and CHROMAgar Listeria for 24 h or 48 h. The evaluation of the total recovery of injured cells was also calculated based on the costs involved in the preparation of media for each protocol. Results indicate that the mUSDA method is best able to aid the recovery of heat-injured, freeze-injured, and heat-freeze-injured cells and was shown to be the most cost effective for heat-freeze-injured cells.

• Journal of Microbiology
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• v.40 no.2
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• pp.109-118
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• 2002

The present work is aimed at providing additional new pure cultures of oxalate utilizing bacteria and its preliminary characterization for further work in the field of oxalate-metabolism and taxonomic studies. The taxonomy of 14 mesophilic, aerobic oxalotrophic bacteria isolated by an enrichment culture technique from soils rhizosphers, and the juice of the petiole/stem tissue of plants was investigated. Isolates were characterized with 95 morphological, biochemical and physiological tests. Cellular lipid components and carotenoids of isolates were also studied as an aid to taxonomic characterization. All isolates were Gram-negative, oxidase and catalase positive and no growth factors were required. In addition to oxalates, some of the strains grow on methanol and/or formate. The taxonomic similarities among isolates, reference strains or previously reported oxalotrophic bacteria were analysed by using the Simple Matching (S/ sub SM/) and Jaccard (S$\_$J/) Coefficients. Clustering was performed by using the unweighted pair group method with arithmetic averages (UPGMA) algorithm. The oxalotrophic strains formed five major and two single-member clusters at the 70-86% similarity level. Based on the numerical taxonomy, isolates were separated into three phenotypic groups. Pink-pigmented strains belonged to Methylobacterium extorquens, yellow-pigmented strains were most similar to Pseudomonas sp. YOx and Xanthobacter autorophicus, and heterogeneous non-pigmented strains were closely related to genera Azospirillum, Ancylobacter, Burkholderia and Pseudomonas. New strains belonged to the genera Pseudomonas, Azospirillum and Ancylobacter that differ taxonomically from other known oxalate oxidizers were obtained. Numerical analysis indicated that some strains of the yellow-pigmented and nonpigmented clusters might represent new species.

• Restorative Dentistry and Endodontics
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• v.44 no.3
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• pp.27.1-27.12
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• 2019

This case report describes a technique in which endodontic treatment and permanent indirect restoration were completed in the same clinical appointment with the aid of a computer-aided design/computer-aided manufacturing (CAD/CAM) system. Two patients were diagnosed with irreversible pulpitis of the mandibular first molar. After access preparation, root canals were located, irrigation was performed until bleeding ceased, and the coronal tooth structure was prepared for indirect restoration. Then, utilizing an interim 3-mm build-up of the endodontic access cavity, a hemi-arch digital scan was performed with an intraoral scanner. Subsequent to digital scanning, restoration design was performed simultaneously with the endodontic procedure. The root canals were shaped using the Race system under irrigation with 2.5% sodium hypochlorite followed by root canal filling. The pulp chamber was subsequently filled with a 3-mm-thick composite resin restoration mimicking the interim build-up previously utilized to facilitate block milling in the CAD/CAM system. Clinical try-in of the permanent onlay restoration was followed by acid etching, application of a 5th generation adhesive, and cementation of the indirect restoration. Once the restoration was cemented, rubber dam isolation was removed, followed by occlusal adjustment and polishing. After 2 years of follow-up, the restorations were esthetically and functionally satisfactory, without complications.

• Korean Journal of Veterinary Research
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• v.62 no.1
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• pp.10.1-10.9
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• 2022

Feline panleukopenia virus (FPV) causes fatal leukopenia and severe hemorrhagic diarrhea in cats. Although FPV isolates have been reported worldwide from several animals, the biological and genetic features of South Korean FPVs remain unclear. We characterized molecularly South Korean FPV isolates. Crandell-Rees feline kidney (CRFK) cells were used to isolate FPV from 60 organ homogenates. The isolates were confirmed to be FPVs via analyses of cytopathic effects, immunofluorescence studies, electron microscopy, and polymerase chain reaction. Viral genetic analyses used the full VP2 sequences. Eight isolates propagated in CRFK cells were confirmed to be FPVs. All isolates yielded viral titers ranging from 10^4.5 to 10^6.0 TCID₅₀/mL 5 days after inoculation into CRFK cells and exhibited hemagglutination titers ranging from 2⁷ to 2¹² (using pig erythrocytes). The Korean FPV isolates grew well in cat cells such as CRFK and Fcwf-4 cells. The FPV isolates were most similar to the KS42 strain isolated from a Korean cat in 2008. The FPV isolates will serve as useful antigens in future sero-epidemiological studies and will aid in the development of diagnostic tools.