• Proceedings of the Korean Environmental Health Society Conference
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• 2005.11a
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• pp.150-153
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• 2005

A gas chromatography/electron impact mass spectrometric assay method was developed for the determination of Hb-adduct, 2-(hydroxyethyl)valine (HEVal), of ethylene oxide(EO). Globin was separated from hemoglobin by acid iso-propanol and ethyl acetate, then HEVal was isolated as PFPITH-HEVal by Edman degradation. PFPITH-HEVal was silylated with N-methyl-N-(tert-butyl-dimethylsilyl)trifluoroacetamide(MTBDMSTFA)-NH4I (1000:4) under catalysis of dithioerythritol. The detection limit of the assay was 5.8 pmol/g based upon assayed hemoglobin of 0.1g. Two groups of mice were exposed to EO for 0.5 and 1.0 hr/day, respectively at 400ppm during 4 weeks. As the result, the adduct levels increased according to the exposure time with the linearity of 0.7011 and 0.8914, respectively, HEVal was very valuable as biomarker for the exposure of EO. In human, HEVal was analyzed until 8.33 pmol/mg.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.119-126
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• 1986

A periplasmic endoprotease, named protease Pi, was purified to homogeneity from Escherkchia coli by conventional procedure with insulin as substrate. This enzyme degrades insulin and glucagon to trichloroacetic acid-soluble meterials, but shows little or no hydrolysis of bovine serum albumin, casein or globin. Its molecular weight was 110, 000 when determined by gel filtration on Sephacryl S-300 and was 105, 000 when estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Thus, it appears to be single polypeptide. This snzyme is metalloprotease, since it is completely inhibited by o-phenanthroline and can be activated by addition of divalent metal cations, such as $Mg^{2+}\;and\;Co^{2+}$. It is destinct from protease Ci, a cytoplasmic insulin degrading enzyme, since protease Pi is localized to the periplasm. Since protease Pi selectively degrades GTP cyclohydrolase I, it appears to play a role in the regulation of pteridine biosynthesis.

• BMB Reports
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• v.39 no.3
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• pp.292-296
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• 2006

DNA sequencing has resulted in an abundance of data on DNA sequences for various species. Hence, the characterization and comparison of sequences become more important but still difficult tasks. In this paper, we first give a 2-D ladderlike graphical representation for the characteristic sequences of a DNA sequence, and then construct a 3-component vector, in which the normalized ALE-indices extracted from such three 2-D graphs via D/D matrices are individual components, to characterize the DNA sequence. The examination of similarities/dissimilarities among sequences of the $\beta$-globin genes of different species illustrates the utility of the approach.

• Archives of Pharmacal Research
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• v.28 no.8
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• pp.963-969
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• 2005

Many reports have stated that some of the pathogenic bacteria can obtain iron from ferroproteins, such as cytochrome C, ferritin, hemin, hemoglobin, and myoglobin. These reports prompted us to determine if an opportunistic pathogenic fungus, Candida albicans, can utilize ferroproteins to circumvent the iron-regulatory effect of transferrin. The following assays were carried out to measure in vitro growth stimulation by the ferroproteins: as an initial step, C. albicans was cultured in iron-free (pretreated with apotransferrin for 24h) culture medium. Once Candida albicans yeast cell growth reached stasis from iron starvation, individual ferroproteins were added to the culture media. Results showed that hemin, hemoglobin, and myoglobin supported a partial growth recovery. Additional studies with haptoglobin, a serum protein that interacts with the globin moiety of certain ferroproteins, established that C. albicans could obtain iron from the haptoglobin-ferroprotein complexes. These data indicate that the heme part of the ferroproteins is the source of iron. This implies that heme oxygenase, CaHMX1 might be involved in bringing about dissociation of heme-containing protein for iron-acquisition. In addition, anticandidal activity of transferrin takes place not only by the process of iron regulation, but also by direct interaction with the yeast cells.

• Journal of Preventive Medicine and Public Health
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• v.36 no.4
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• pp.373-376
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• 2003

Objectives : Peripheral blood-buffy coat fractions (N=14,956) have been stored at $-70^{\circ}C$ in the headquarter of the Korean Multicenter Cancer Cohort (KMCC), since 1993. To study the future molecular etiology of cancers using specimens of the cohort, properly stored specimens are necessary, Therefore, the DNA-viability of the bully coat samples was investigated. Methods : Buffy coat fraction samples were randomly selected from various collection areas and years (N=100). The DNA viability was evaluate from the UV-absorbent ratios at 260/280nm and the PCH for $\beta$-globin was performed with genomic DNA isolated from the buffy coat. Results : PCR products were obtained from 85 and 98% of the C and H area-samples, respectively, using 50 or $100{\mu}l$ of the buffy coat. There were significant differences in the yields of the PCR-amplifications from the C and H areas (p<0.05), which was due to differences in the homogenization of the buffy coat fractions available as aliquots. The PCR-products were obtained from all of the samples (N=7) stored at the C area-local confer, but the other aliquots stored at the headquarter were not PCR-amplified, Therefore, the PCR products in almost all the samples, even including the DNA-degraded samples, were obtained. In addition, an improvement in the DNA isolation, i,e. approx. 1.6 fold, was found after using extra RBC lysis buffer. Conclusions : PCR products for $\beta$-globin were obtained from nearly all of the samples. The regional differences in the PCR amplifications were thought to have originated from the different sample-preparation and homogenization performance. Therefore, the long term-stored buffy coat species at the KMCC can be used for future molecular studies.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.614-618
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• 2001

Low-threshold T-type $Ca^{2+}$ channels are distinctive voltage-operated gates for external $Ca^{2+}$ entry around a resting membrane potential due to their low voltage activation. These phenomena have already been extensively studied due to their relevance in diverse physiological functions. Recently, three T-type $Ca^{2+}$ channel ${\alpha}$$_1$subunits were cloned and their biophysical properties were characterized after expression in mammalian expression systems. In this study, ${\alpha_IG} and {\alpha_IH}$ low-threshold $Ca^{2+}$ channels were expressed and characterized in Xenopus oocytes after adding 5' and 3'untranslated portions of a Xenopus ${\beta}$ globin to improve their expression levels. The added portions dramatically enhanced the expression levels of the ${\alpha_IG} and {\alpha_IH}$ T-type channels. When currents were recorded in 10 mM $Ba^{2+}$ as the charge carrier, the activation thresholds were about -60 mV, peak currents appeared at -20 mV, and the reversal potentials were between +40 and +45. The activation time constants were very similar to each other, while the inactivation time constants of the ${\alpha_IG}$ currents were smaller than those of ${\alpha_IH}$. Taken together, the electrophysiological properties of the ${\alpha_IG} and {\alpha_IH}$ channels expressed in Xenopus oocytes were similar to the previously reported characteristics of low-threshold $Ca^{2+}$ channel currents.

• Molecules and Cells
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• v.20 no.1
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• pp.57-68
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• 2005

Murine erythroleukemia (MEL) cells are widely used to study erythroid differentiation thanks to their ability to terminally differentiate in vitro in response to chemical induction. At the molecular level, not much is known of their terminal differentiation apart from activation of adult-type globin gene expression. We examined changes in gene expression during the terminal differentiation of these cells using microarray-based technology. We identified 180 genes whose expression changed significantly during differentiation. The microarray data were analyzed by hierarchical and k-means clustering and confirmed by semi-quantitative RT-PCR. We identified several genes including H1f0, Bnip3, Mgl2, ST7L, and Cbll1 that could be useful markers for erythropoiesis. These genetic markers should be a valuable resource both as potential regulators in functional studies of erythroid differentiation, and as straightforward cell type markers.

• Environmental Mutagens and Carcinogens
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• v.18 no.2
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• pp.83-88
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• 1998

To detect the mutation in a given sequence, there are variety of methods developed by use of the gel electrophoresis. One of the methods, TGGE (Temperature Gradient Gel Electrophoresis), is a popular technique because it can detect mutations in DNA fragment with ease and at low cost. This study used 200 bp BamHI-digested DNA fragment containing the human $\varepsilon$-globin promoter which was mutated[$\varepsilon$ F1*(-141), GATA- I*(-163), and GATA-1* & $\varepsilon$F1]. This BamHI-digested DNA fragment was directly used to detect the mutated DNA fragment on 50% denaturant gel with temperature gradient of 45$^{\circ}C$ through $53^{\circ}C$. In agreement with the theoretical result of MELTSCAN program (Brossette and Wallet, 1994) the mobilities of mutated DNA fragments were shown to be nearly distinguished on the temperature gradient gel. In contrast to the above result the heteroduplex analysis under the temperature gradient condition was shown to detect the mutated DNA fragments through the heteroduplex formation between strands of mutated DNA and wild-type DNA.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1158-1163
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• 1999

The purpose of this research is to measure nutrition counseling effects for improving iron status. The major components of the nutrition counseling were iron, MPF(Meat, Poultry, Fish) and vitamin C rich diet therapy, the provision of nutrient supplements and eatting attitude education. Fifteen female volun teers participated and the mean level for hemoglobin(Hgb), hematocrit(Hct), serum iron(S Fe), total iron binding capacity(TIBC), serum ferritin(SF) of subjects was 11.9±1.3g/dl, 37.0±2.7%, 57.7 ±33.9 g/dl, 409.1±56.2 g/dl, 8.6±3.5ng/ml, respectively. To evaluate the effect of iron status improvement by the nutrition couseling, 10 subjective symptoms, hematological indice and eating attitude were measured after implementation the nutrition counseling. Some subjective symptoms such as 'cold hands and foot', 'slow to recover', 'reduced concentrate', 'poor memory', 'inflammed inner mouth' were improved significantly. The hemoglobin, hematocrit, mean cell volume(MCV), mean cell hemoglobin(MCH) and mean cell hemo globin concentration(MCHC) were increased significantly. And eating attitude was improved significantly as well. It is suggested from the results that the nutrition counseling of this study can be effective to improve iron status.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.27-33
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• 1996

납중독에 대한 마늘의 antidotic effect를 조사하기 위한 4주간의 실험에서 , rat 체중 kg 당 중 (7일간) 1회초산납 100mg을 투여한 rat에 매일 마늘즙을 식이의 4%로 투여한 실험군(LG)과 초산납과 함께 중금속 해독제인 N-acetyl penicillamine을 매일 rat 체중 kg당 100mg 투여한 실험군 (LP)의 체중 증가율 비교에서 초산납만을 투여한 실험군(L)보다 LG군과 LP군 모두 유의성 있는 rat 성장률 개선효과 (각각 +13.3%과 +22.3%)를 보였다. L군 rat의 외관과 해부검사에서는 장기들(위, 간장, 신장)의 병변(damage)이 매우 미미하게 관찰되었으나 혈액검사에서 GOT, alkaline phos-phatase, blood uric acid, blood urea nitrogen, crea-tinine, bilitrubin 값이 유의적을 증가하여 납중독에 의한 장기(organs) 특히 신장 기능의 현저한 장해를 보였다. 그러나 LG군이 이들 측정값이 L군보다 유의성의 차로 낮은 값을 보여 LP군과 거의 비슷한 수준이었다. 특히 L군에서는 Pb 중독으로 인하여 hemo-globin 량이 정상 이하(10.37g/dl)로 감소되었으나 LG군에서는 L군에서와 같이 거의 정산 (12.32g/dl)을 유지하였다. L군의 혈액, 간장 및 신장의 납 합량은 각각 0.281, 0.250, 0.403ppm으로 대조군 보다 매우 높았으나 LG군은 대조군에 가깝게 그리고 LP군과는 거의 같은 수준(각각 0.182, 0.131, 0.253ppm)으로 낮아졌다. 이상의 실험 결과에서 마늘이 rat의 납중독에 미치는 효과를 N-acetyl penicillamine의 해독 효과와 비교할 때 마늘의 해독 효과라고 볼 수 있는 유의성있는 측정값들이 관찰되었다.