• Journal of Radiation Protection and Research
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• v.9 no.2
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• pp.103-111
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• 1984

A convenient method of $^{99m}Tc$-methyl-ethyl-ketone (MEK) extraction technique was developed and a mobile $^{99m}Tc$-extraction generator was designed. The MEK extraction and the phase separation of $^{99m}TcO^-{_4}$ were carried out with a simple procedure in the same container. The shielding of $^{99}Mo$ radioactivity was made with one lead container. The system was simplified by shielding $^{99m}TcO_4{^-}({\gamma}_e=0.14\;MeV)$ separately. $^{99m}TcO^-{_4}\;in\;^{99m}Tc-MEK$ extract was recovered by adsorption and elution only, and therefore, the possibility of volatilization was reduced. The volume of $^{99m}TcO^{-}{_4}$-saline product was reduced to 1 ml by using a small alumina column and the column operation time was shortened. The separation time of $^{99m}Tc$ was reduced to 30 minutes, and the operation was carried out at the outside of the shielding. The system was designed to operate under the condition of bacteria-free.

• Journal of the Korea Safety Management & Science
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• v.4 no.1
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• pp.49-56
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• 2002

In this case study, results of the explosion accident at MEK-PO factory were analysed by using the consequence analysis of quantitative hazard assessment and the explosion energy, the burst pressure of vessel, and overpressures at the explosion center and at 300m distance from the explosion center were estimated, respectively. As a result, we found that a cause of accident was the runaway reaction of product(MEK-PO) because of the molecular expansion in vessel and that the possibility of the runaway reaction was classified the mechanical failure(the obstacle of refrigerator or the shutdown valve), design error, and operating error by lack of thermochemical knowledge. Also, the evasive action to prevent accident was suggested.

• YAKHAK HOEJI
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• v.55 no.2
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• pp.138-144
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• 2011

The aim of present study was to investigate the possible influence and related mechanism of resveratrol on U-46619 (high concentration)-induced vasoconstriction. Agonist-induced vascular smooth muscle contractions involve the activation of thick or thin filament pathway. However, there are no reports addressing the question whether this pathway is involved in resveratrol-induced relaxation in rat aortae contracted with high U-46619. We hypothesized that MEK or Rho-kinase inhibition plays a role in vascular relaxation evoked by resveratrol in rat aortae. Endothelium-denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Resveratrol fully inhibited U-46619 in low concentration-induced contraction regardless of endothelial function. However, resveratrol partially decreased U-46619 in high concentration-induced contraction regardless of endothelial function. Interestingly, only in U-46619 (high concentration)-induced contraction, no significant decrease was observed in phospho-ERK1/2 levels and slight decrease in phospho-MYPT1 levels suggesting that additional pathways different from them or endothelial nitric oxide synthesis might be involved in the vasorelaxation. In conclusion, in high U-46619-contracted rat aortae, resveratrol showed relaxation response regardless of endothelial function significantly but slightly decreasing MYPT1 phosphorylation rather than ERK1/2 phosphorylation.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.1
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• pp.69-74
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• 2016

The present study was undertaken to investigate the influence of cardamonin on vascular smooth muscle contractility and to determine the mechanism(s) involved. Denuded aortic rings from male rats were used and isometric contractions were recorded and combined with molecular experiments. Cardamonin significantly relaxed fluoride-, phenylephrine-, and phorbol ester-induced vascular contractions, suggesting that it has an anti-hypertensive effect on agonist-induced vascular contraction regardless of endothelial nitric oxide synthesis. Furthermore, cardamonin significantly inhibited the fluoride-induced increase in pMYPT1 level and phenylephrine-induced increase in pERK1/2 level, suggesting inhibition of Rho-kinase and MEK activity and subsequent phosphorylation of MYPT1 and ERK1/2. This study provides evidence that the relaxing effect of cardamonin on agonist-induced vascular contraction regardless of endothelial function involves inhibition of Rho-kinase and MEK activity.

• Biomedical Science Letters
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• v.24 no.3
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• pp.213-220
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• 2018

Triglyceride (TG) is known to be associated with inflammatory disease including atherosclerosis. In a variety of atherosclerosis models, T lymphocytes are localized in the earliest lesions of atherosclerosis. T cell associated cytokines such as $TNF-{\alpha}$ and $IFN-{\gamma}$ have pre-dominant inflammatory effects in chronic vascular diseases. In our previous study, we found that the expression of $TNF-{\alpha}$ and its receptor, $TNF-{\alpha}R$ was increased when Jurkat T lymphocyte cell lines were exposed to TGs. Therefore, experiments were conducted to determine which cell signaling pathway are involved in the increase of $TNF-{\alpha}$ and $TNF-{\alpha}R$ expression by TGs. To identify signal transduction pathways involved in TG-induced upregulation of $TNF-{\alpha}$, we treated TG-exposed Jurkat T cells with specific inhibitors for MEK1, PI3K, $NF-{\kappa}B$ and PKC. We found that inhibition of the MEK1 pathway blocked TG-induced upregulation of $TNF-{\alpha}$. However, the expression level of $TNF-{\alpha}R$ did not change with any signal transduction inhibitor. Based on this observation, we suggest that increase of exogenous TG induces increase of $TNF-{\alpha}$ expression through MEK1 pathway in Jurkat T cells. In addition, it was confirmed that the increase of $TNF-{\alpha}$ and $TNF-{\alpha}R$ expression by TGs occurs via different pathways.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.2
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• pp.135-144
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• 2001

This study was performed to measure airborne dimethylformamide(DMF), methyl ethyl ketone(MEK) and toluene and their urinary metabolites concentrations and to determine the relationship between airborne and urinary concentration. Airborne samples and their urinary metabolites were measured 98 male workers who work for 8 synthetic leather factories in a portion of Kyoung-In area. Urine samples were collected at end-of-shift to estimate the exposure levels. 1. The concentration of airborne DMF by process was 8.81 ppm for wet-mixing, 15.05 ppm for wet-coating, 6.03 ppm for dry-mixing, 5.58 ppm for dry-coating, 5.37 ppm for printing, and 9.03 ppm for total. There was statistically significant difference by process. Urinary NMF concentrations of wet-mixing, wet-coating, dry-mixing, dry-coating and printing were $90.55mg/{\ell}$, $79.80mg/{\ell}$, $39.86mg/{\ell}$, $25.23mg/{\ell}$, and $38.15mg/{\ell}$, respectively, and total geometric mean was $56.24mg/{\ell}$. There was significant difference by process. 2. The concentration of airborne MEK by process was 1.89 ppm for wet-mixing, 1.96 ppm for wet-coating, 10.33 ppm for dry-mixing, 29.24 ppm for dry-coating, 14.98 ppm for printing, and 4.87 ppm for total. There was statistically significant difference by process. Urinary MEK concentrations of wetmixing, wet-coating, dry-mixing, dry-coating and printing were $0.93mg/{\ell}$, $0.70mg/{\ell}$, $3.29mg/{\ell}$, $3.29mg/{\ell}$, and $1.06mg/{\ell}$, respectively, and total geometric mean was $1.25mg/{\ell}$. There was statistically significant difference by process. Urinary MEK 3. The concentration of airborne toluene by process was 0.35ppm for wet-mixing, 0.42ppm for wet-coating, 2.95ppm for dry-mixing, 11.67ppm for dry-coating, 4.88ppm for printing, 1.24ppm for total. There was statistically significant difference by process. Urinary hippuric acid concentrations of wet-mixing, wet-coating, dry-mixing, dry-coating and printing were 0.24g/g creatinine, 0.21g/g creatinine, 0.34g/g creatinine, 0.52g/g creatinine, and 0.29g/g creatinine, respctively and total geometric mean was 0.28g/g creatinine. There was statistically significant difference by process. 4. No. of exceeded KPEL was 40 workers(40.8%) for DMF(10ppm), 1 worker(1.0%) for MEK(200ppm), and no worker for toluene(100ppm). No. of exceeded KBEI was 62 workers(63.3%) for urinary NMF($40mg/{\ell}$), 29 workers(29.6%) for urinary MEK, 1 worker(1.0%) for urinary hippuric acid. 5. The regression equations were Log(NMF)=0.4094*Log(DMF)+1.3587(r=0.4516) for DMF, Log(MEKU)=0.1859*Log(MEK)-0.0324(r=0.3303) for MEK, Log(HA)=0.2106*Log(Toluene)-0.5685(r=0.4497) for toluene. Synthetic leather factory workers expose to 3 kinds of organic solvents which are DMF, MEK and toluene. Their urinary NMF and MEK levels were higher than their concentration levels through respiratory. It seems that the urinary levels were affected skin absorption for working habit and alcohol intake.

• The Korean Journal of Mycology
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• v.46 no.2
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• pp.161-176
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• 2018

Fungal ${\beta}$-glucan, known to have immunostimulatory and antitumor activities, can be recognized by host immune cells as one of the pathogen-associated molecular patterns (PAMPs). Although there are several reports on the diverse immunostimulatory activities of ${\beta}$-glucan, little is known about the intracellular signal transduction of ${\beta}$-glucan. Stimulation of RAW264.7 macrophage cells with ${\beta}$-glucan from Ganoderma lucidum induced the expressions of dectin-1, toll-like receptor 2 (TLR2), TLR4, and TLR6 at the transcription stage. Treatment with ${\beta}$-glucan also induced inflammatory mediators such as macrophage inflammatory proteins (MIP)-$1{\alpha}$, MIP-$1{\beta}$, MIP-$1{\gamma}$, interleukin (IL)-$1{\beta}$, and tumor necrosis factor (TNF)-${\alpha}$. Treatment of the cells with polymyxin B, an inhibitor of lipopolysaccharides (LPS), blocked the induction of inflammatory mediators in LPS- or ${\beta}$-glucan-stimulated systems. Pretreatment of the cells in our cell culture system with LY294002, a phosphoinositide 3-kinase (PI3K) inhibitor, or U0126, a mitogen-activated protein kinase/extracellular-signal-regulated kinase (MAPK/ERK) kinase (MEK)1/MEK2 inhibitor, led to a reduction in the induction of inflammatory mediators in a concentration-dependent manner. These results show that stimulation of the macrophage cells by ${\beta}$-glucan induced the expressions of both dectin-1 and TLRs. We also found that the PI3K/Akt and MEK pathways were involved in the induction of inflammatory mediators in macrophage cells during intracellular signal transduction of ${\beta}$-glucan.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.1
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• pp.25-33
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• 2006

The objective of this research is to improve the adsorption capacity of adsorbent made from MSWI (Municipal Solid Waste Incinerator) fly ash by surface oxidation. Used oxidation agents were $HNO_{3}$, $H_{2}SO_{4}$ and $(NH_{4})_{2}S_{2}O_{8}$. These agents can modify the surface property of an adsorbent such as specific surface area, pore volume, and functional group. The surface structure was studied by BET method with $N_{2}$ adsorption. The acid value and base value were determined by Boehm's method. The adsorption properties were investigated with benzene and MEK (Methylethylketone). According to the results, the specific surface area of the adsorbent was increased from 309.2 $m^{2}$/g to 553.2 $m^{2}$/g by $HNO_{3}$ oxidation. But $H_{2}SO_{4}$ and $(NH_{4})_{2}S_{2}O_{8}$ oxidation was decreased slightly. After Oxidation, surface acid value increased, but base value decreased. FAA-N shows the highest acid value. The content of oxygen increased greatly and oxygen group was created on the adsorbent surface. The surface oxidation improved the adsorbing capacity for MEK. The amount of adsorbing MEK was increased from 189 $m^{2}$/g to 639 $m^{2}$/g by $HNO_{3}$ oxidation.

• YAKHAK HOEJI
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• v.58 no.4
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• pp.223-228
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• 2014

The present study was undertaken to investigate the influence of sulforaphane on vascular smooth muscle contractility and to determine the mechanism involved. We hypothesized that sulforaphane, the primary ingredient of broccoli of cruciferous vegetables, plays a role in vascular relaxation through inhibition of Rho-kinase in rat aortae. Intact of denuded arterial rings from male Sprague-Dawley rats were used and isometric tensions were recorded using a computerized data acquisition system. Interestingly, sulforaphane significantly inhibited fluoride, phorbol ester or thromboxane $A_2$ mimetic-induced contraction in denuded muscles suggesting that additional pathways different from endothelial nitric oxide synthesis such as inhibition of Rho-kinase or MEK might be involved in the vasorelaxation. Furthermore, sulforaphane inhibited thromboxane $A_2$-induced increases in pERK1/2 levels suggesting the mechanism including inhibition of thromboxane $A_2$-induced increases in ERK1/2 phosphorylation. This study provides evidence that sulforaphane induces vascular relaxation through inhibition of Rho-kinase or MEK in rat aortae.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.15 no.1
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• pp.1-28
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• 2011

Objectives: A study on the importance and consistency of pulse-daignosis in the Dongeuibogam Methods: We used Deyeuk Dongeuibogam of Dongeuibogam publishing company from original photographic edition. Results: The frequency of 27 mek (pulse condition) in Dongeuibogam is as in the following. Bumek (Floating pulse) appeared 120(8.9%) times, wanmek (moderate pulse) appeared 28(2%) times, chokmek (running pulse) appeared 7 (0.5%) times, gyumek (hollow pulse) appeared 19 (1.4%) times, saekmek (uneven pulse) appeared 33 (2.4%) times, sapmek (uneven pulse) appeared 51 (3.8%) times, kyulmek (knotted pulse) appeared 18 (1.3%) times, whalmek (slippery pulse) appeared 69 (5.1%) times, chimek (slow pulse) appeared 43 (3.2%) times, demek (intermittent pulse) appeared 13 (1%) times, silmek (replete pulse) appeared 45 (3.3%) times, bokmek (deep-sited pulse) appeared 29 (2.1%) times, neomek (firm pulse) appeared 4 (0.3%) times, hyunmek (taut pulse) appeared 110 (8.1%) times, yumek (soft pulse) appeared 20 (1.5%) times, dongmek (short and rapid pulse) appeared 16 (1.2%) times, kinmek (tense pulse) appeared 67 (5%) times, yakmek (weak pulse) appeared 46 (3.4%) times, semek (thready pulse) appeared 62 (4.6%) times, hongmek (full pulse) appeared 50 (3.7%) times, jangmek (long pulse) appeared 14 (1%) times, sakmek (rapid pulse) appeared 103 (7.6%) times, mimek (indistinctive pulse) appeared 65 (4.8%) times, danmek (short pulse) appeared 16 (1.2%) times, demek (large pulse) appeared 106 (7.9%) times, chimmek (deep pulse) appeared 112 (8.3%) times, heomek appeared 70 (5.2%) times, sanmek (scattered pulse) appeared 14(1%)times. Conclusions: We can know Donguibogam is given on the basis 27mek (pulse condition), because the frequency of 27mek (pulse condition) is high. But there are another expressions. So we can not say that Donguibogam is consistent in expressing mekbub(the way of pulse-diagnosis).