• Title/Summary/Keyword: Biological sample

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An Automated Fiber-optic Biosensor Based Binding Inhibition Assay for the Detection of Listeria Monocytogenes

  • Kim, Gi-Young;Morgan, Mark;Ess, Daniel;Hahm, Byoung-Kwon;Kothapalli, Aparna;Bhunia, Arun
    • Food Science and Biotechnology
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    • v.16 no.3
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    • pp.337-342
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    • 2007
  • Conventional methods for pathogen detection and identification are labor-intensive and take days to complete. Biosensors have shown great potential for the rapid detection of foodborne pathogens. Fiber-optic biosensors have been used to rapidly detect pathogens because they can be very sensitive and are simple to operate. However, many fiber-optic biosensors rely on manual sensor handling and the sandwich assay, which require more effort and are less sensitive. To increase the simplicity of operation and detection sensitivity, a binding inhibition assay method for detecting Listeria monocytogenes in food samples was developed using an automated, fiber-optic-based immunosensor: RAPTOR (Research International, Monroe, WA, USA). For the assay, fiber-optic biosensors were developed by the immobilization of Listeria antibodies on polystyrene fiber waveguides through a biotin-avidin reaction. Developed fiber-optic biosensors were incorporated into the RAPTOR to evaluate the detection of L. monocytogenes in frankfurter samples. The binding inhibition method combined with RAPTOR was sensitive enough to detect L. monocytogenes ($5.4{\times}10^7\;CFU/mL$) in a frankfurter sample.

Failure to Support Associations of Neurotrophin-3(NT-3) Gene Polymorphism in Korean Schizophrenic Patients

  • Lee, Yu-Sang;Han, Jin-Hee;Chung, Eun-Kee;Yang, Byung-Hwan;Kim, Hyeong-Seob;Lee, Jung-Sik;Joo, Yeon-Ho;Chai, Young-Gyu
    • Korean Journal of Biological Psychiatry
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    • v.4 no.2
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    • pp.234-236
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    • 1997
  • Though initial report from Japan showed positive association of schizophrenia with dinucleotide repeat polymorphism in the NT-3 gene, subsequent studies showed mixed results. Therefore we conducted a replication study with Korean schizophrenics and matched controls who share similar ethnic background with Japanese population. The frequency of allele of dinucleotide repeat at 147 base pairs in the NT-3 gene was slightly increased, however, failed to reach statistical significance(${\chi}^2$=1.884, df=1, p<0.170) between the two groups. These findings do not support an association of NT-3 gene polymorphism with schizophrenia in Korean sample.

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Endocrine Disruptive Potentials in Surface Water Samples from Taihu Lake, Yangtze Delta

  • Shen, L.;Lin, G.F.;Shen, J.H.
    • Toxicological Research
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    • v.17
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    • pp.319-321
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    • 2001
  • Taihu Lake is a major water source for part of Yangtze Delta, which is one of the most urbanized and economically prosperous areas in China. In last couple of decades, some parts of the lake were highly polluted due to eutrophication. This study analyzed dioxin-like potential and mutagenic potential in surface water samples from Taihu Lake. The samples were prepared by XAD-2 resin procedure. A batch of biological assays, including dioxin-like potential microassay with the rat hepatocyte cell line H411E, and Ames test was employed in the research. Results showed that jour water samples have high content of dioxin-like biological potential, the highest activity TEQ to 2,3,7,8-TCDD was 48 pg/ι in sample 1. The mutagenic effect with reading-frame shifting mechanism was confirmed in 3 of 4 samples. The effective sewage treatment facilities and reliable monitoring surveillance system are urgently needed for this area.

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Characterization of a Bioflocculant Produced by an Isolate, Bacillus megaterium G31

  • Chung, Sun-Ho;Kim, Hyung-Woo;Moon, Myeng-Nim;Yang, Young-Ki;Rhee, Young-Ha
    • Korean Journal of Environmental Biology
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    • v.21 no.4
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    • pp.358-365
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    • 2003
  • A bacterial strain capable of producing a novel bioflocculant was isolated from a biofilm sample and identified as Bacillus megaterium G31. The highest biopolymer yield was achieved when the organism was cultivated in a medium containing acetate as the sole carbon source and ($NH_4)_2HPO_4$as the nitrogen source. In kaolin suspension, the flocculating activity was highest at 170 mg I$^{-1}$ and decreased at the higher bioflocculant concentrations. The crude bioflocculant produced by the organism was purified by ethanol precipitation and gel permeation chromatography. The FTIR spectrum of the purified bioflocculant revealed that the bioflocculant might be a heterogeneous polysaccharide composed of hexosamines and neutral sugars. The analysis of sugar components of the bioflocculant using high performance anion-exchange chromatography showed that the sugar constituents of the bioflocculant were glucosamine, fucose, galactosamine, galactose, glucose, mannose in approximate molar ratio of 4 : 1 : 6 : 3 : 8 : 19. Its flocculating activity was stimulated by various cations. The bioflocculant was thermo-stable and retained 64% of its original activity after heating at $100^{\circ}C$ for 50 min.

Micro-channel Embedded Soft Contact Lens for Tear Biomolecule Sampling (눈물의 생체 분자 추출을 위한 미세유관이 탑재된 유연한 콘택트 렌즈)

  • Kim, Ockchul;Park, HyungDal;Song, Young-won;Kim, Jinseok
    • Journal of Biomedical Engineering Research
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    • v.37 no.5
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    • pp.178-185
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    • 2016
  • Tear is a promising biological fluid for non-invasive health monitoring. It has been studied in the past to be a possible candidate for the diagnosis of certain systemic diseases, such as breast cancer, multiple sclerosis, prostate cancer, and diabetes. However, currently existing methods for collecting and extracting tear from the human eye causes inconsistencies in the biomolecule concentrations of the tear sample due to the irritating nature of the process. In response, we designed and fabricated a microfluidic system embedded soft contact-lens for the purpose of tear sampling. The lens was then tested with artificial tear for its tear sampling capability, and found to be able to find concentration equilibrium within 50 minutes. Additionally, simulation was carried out to further optimize the design so that tear sampling rate matched the natural tear turn-over rate of 1 microliter per minute.

Factors Relating to Social Physique Anxiety in Adolescent Girls (청소년기 여학생의 사회적 체격불안 관련 요인)

  • Lee, Eun-Joo
    • Women's Health Nursing
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    • v.14 no.2
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    • pp.93-103
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    • 2008
  • Purpose: This descriptive study was to explore the factors relating to Social Physique Anxiety(SPA) in the adolescent girls(N=700). These factors included the biological(level of school[age], period of menstruation, and BMI), the sociocultural(Influence of Mass Media, [IMM], Stereotype of Ideal Female Body[SIFB], type of school, perceived figure, and ideal figure) and the BW control-related factors(experience of bodyweight [BW] control, satisfaction at the result of BW control, and motive of BW control). Method: The sample was 700 girls of the middle and high schools in Jeju-do. The data was collected by the self-reported questionnaire and processed with the SPSS Win 12.0 program. Result: 26% of the variance in SPA was explained by the biological factors(level of school) and the sociocultural factors (perceived figure, ideal figure, type of school, and IMM). SPA, IMM, and SIFB were significantly correlated with each others(r=1,65-2.92, p<.05). The mean SPA scores according to BW control-related factors were significantly different. Conclusion: This results suggest that media education is necessary to reduce or eliminate the adolescent girl's SPA. In addition, SPA needs to be considered as the important concept for the future nursing researches and interventions related to BW control.

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Modification of Physicochemical Properties of Arrowroot Starch by Heat-Moisture Treatment (수분-열처리에 따른 칡 전분의 물리화학적 성질)

  • Cha, Hwan-Soo;Kim, Kwan;Kim, Sung-Kon
    • Applied Biological Chemistry
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    • v.27 no.4
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    • pp.252-258
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    • 1984
  • Physicochemical properties of arrowroot starch, which was adjusted to 18, 21, and 24% moisture and heated at $100^{\circ}C$ for 16hr, were investigated. X-ray diffraction pattern was changed from C- to A-pattern upon treatment(24% moisture). The swelling powere and solubility decreased by heat-moisture treatment. The treated sample was gelatinized at higher temperature than untreated one. Water-binding capacity was drastically increased as the moisture level was decreased. Amylograph hot paste viscosities were decreased upon treatment.

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Microbiological Quality Assessment of a Local Milk Product, Kwacha Golla, of Bangladesh

  • Rahman, M.M.;Rahman, M.Mashiar;Arafat, S.M.;Rahman, Atiqur;Khan, M.Z.H.;Rahman, M.S.
    • Applied Biological Chemistry
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    • v.51 no.4
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    • pp.251-257
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    • 2008
  • Different types of milk products, such as kwacha golla, mawa, cheese, curd, and chocolate are popular in Bangladesh. However, the microbiological safety of these products is poorly understood. This study was performed to assess the microbiological quality of kwacha golla, a local milk product. Kwacha golla samples were collected from ten different areas of Rajshahi and Kushtia regions, and the quality of the each sample was assessed using various parameters including standard plate count, total coliform, fecal coliform, total fungi, and spore-forming bacteria, as well as food-borne microorganisms. Out of 300 samples, total coliform was detected at 56.66% (n= 300), exceeding the minimum allowable limit of 36.66%. Similarly, experiments were carried out with fungi and food-borne pathogens including Escherichia coli, Listeria monocytogenes, Salmonella sp., and Staphylococcus aureus. Results revealed 85.33, 53, and 49.33% of the samples were contaminated by fungi, E. coli, and L. monocytogenes, respectively. However, all samples showed no contaminations of Salmonella sp. and Staphylococcus sp. Therefore, this study could be helpful to the people of Bangladesh by providing information on the possibility of a major health problem caused by the consumption of kwacha golla.

Studies on Sensory Evaluation -[Part IV] New Modified Triangle Test- (관능검사(官能檢査)에 관한 연구(硏究) -[제4보(第4報)] 3점비교법(點比較法)의 신변형(新變形)에 대하여-)

  • Hong, Jin
    • Applied Biological Chemistry
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    • v.20 no.3
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    • pp.285-291
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    • 1977
  • In this paper the new statistical method called "New Modified Triangle Test" is studied. This method is to test the null hypothesis based on the result which comes from evaluating sample size "t", where $t{\geqq}3$, by using Triangle Preference Scale Test. It a confirmed that "New Modified Scheffe's Method 1" can be used for appraising "New Modified Triangle Test". In this report, the weight fraction of in-correct oddity chosen to correct oddity chosen is made 1/2 in terms of chance probability.

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Mainchain NMR Assignments and secondary structure prediction of the C-terminal domain of BldD, a developmental transcriptional regulator from Streptomyces coelicolor A3(2)

  • Kim, Jeong-Mok;Won, Hyung-Sik;Kang, Sa-Ouk
    • Journal of the Korean Magnetic Resonance Society
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    • v.17 no.1
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    • pp.59-66
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    • 2013
  • BldD, a developmental transcription factor from Streptomyces coelicolor, is a homodimeric, DNA-binding protein with 167 amino acids in each subunit. Each monomer consists of two structurally distinct domains, the N-terminal domain (BldD-NTD) responsible for DNA-binding and dimerization and the C-terminal domain (BldD-CTD). In contrast to the BldD-NTD, of which crystal structure has been solved, the BldD-CTD has been characterized neither in structure nor in function. Thus, in terms of structural genomics, structural study of the BldD-CTD has been conducted in solution, and in the present work, mainchain NMR assignments of the recombinant BldD-CTD (residues 80-167 of BldD) could be achieved by a series of heteronuclear multidimensional NMR experiments on a [$^{13}C/^{15}N$]-enriched protein sample. Finally, the secondary structure prediction by CSI and TALOS+ analysis using the assigned chemical shifts data identified a ${\beta}-{\alpha}-{\alpha}-{\beta}-{\alpha}-{\alpha}-{\alpha}$ topology of the domain. The results will provide the most fundamental data for more detailed approach to the atomic structure of the BldD-CTD, which would be essential for entire understanding of the molecular function of BldD.