• Current Optics and Photonics
• /
• 제3권5호
• /
• pp.415-422
• /
• 2019

Retroreflection of vehicle headlights, as induced by spherical glass beads, is a key optical phenomenon that provides road-surface markings with greatly enhanced visibility, thus better securing a driver's safety in the nighttime as well as in unclear daytime. Retroreflectance of glass beads is a quite sensitive function of their refractive index, so that measurement of the refractive index of glass specifically in the shape of spherical beads needs to be performed within a reasonable uncertainty that is tolerable for road-marking applications. The Becke line method has been applied in assessing refractive index of such glass beads as e.g. an industrial standard in the Republic of Korea; however, the reference refractive-index liquids are not commercially available these days for refractive index greater than 1.80 due to the toxicity of the constituent materials. As such, high-refractive-index glass beads require an alternate method, and in this regard we propose a practically serviceable technique with uncertainty tantamount to that of the Becke line method: Based on comparison of calculated and measured retroreflectance values of commercial glass beads, we discover that their refractive index can be determined with reasonable precision via the retroreflectance measurement. Specifically, in this study the normalized retroreflectance originating from a single glass sphere is computed as a function of refractive index using the Fresnel equations, which is then validated as coinciding well with retroreflectance values measured from actual specimens, i.e. glass-bead aggregates. The uncertainties involved are delineated in connection with radius and imperfections of the glass beads.

• 한국토양비료학회지
• /
• 제39권6호
• /
• pp.392-395
• /
• 2006

농경지에 과거에 사용했거나 사용 중인 9종의 제초제가 농경지에 서식하는 지렁이에게 악영향이 있는지 알기위하여 추천사용량, 2배량 및 4배량을 기준으로 토양표토처리법, 침지법, 여지접촉법으로 실험을 수행하였다. 그 결과 토양표토처리법에서 처리양과 제초제 종류와 관계없이 무처리와 비교하여 통계적인 유의성이 없었다. 침지법의 4배량에서 phamid WP는 34%, alra EC는 64%의 치사율을 나타냈고, 여지접촉법의 추천사용량에서 phamid WP는 33%, 2배량에서 phamid WP는 37%, alra EC는 80%, triclopyr EC는 10%, 4배량에서 phamid WP는 96%, alra EC는 80%, triclopyr EC는 37%, glyphosate SL는 47%, Paraco SL는 37%, pyributicarb WP는 10%, Glufosinate-ammonium SL는 33%의 지렁이 치사율을 나타냈다.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제23권6호
• /
• pp.54-72
• /
• 2018

This study reviewed standard operation procedures for fractionation and analytical methods of total petroleum hydrocarbons (TPH) in north america and european countries to aid proper establishment of risk assessment protocols associated with TPH exposure in Korea. In current, the TPH fraction methods established by Massachusetts Department of Environmental Protection (MassDEP) and Total Petroleum Hydrocarbon Criteria Working Group (TPHCWG) are most frequently employed worldwide. Both methods were developed on the basis of direct exposure of TPH from soil, although the method by TPHCWG also took into account the mobility of TPH. Volatile and extractable fractions of petroleum hydrocarbons were analyzed either separately or together. TPH fractionation methods were evaluated based on conservative toxicity values considering the uncertainty of risk assessment in light of current standard protocol for analyzing soil contaminants in Korea, and it was concluded that the method developed by MassDEP is more appropriate.

• Nutrition Research and Practice
• /
• 제16권4호
• /
• pp.435-449
• /
• 2022

BACKGROUND/OBJECTIVES: Cheonggukjang is a traditional fermented soybean paste with significant health-promoting effects. On the other hand, there have been insufficient studies on the safety and efficacy of Cheonggukjang, which is produced using traditional methods containing toxins and biogenic amines (BAs). This study compared the laxative effect of Cheonggukjang, containing high or low levels of toxins and BAs (HTBC or LTBC) in a loperamide (Lop)-induced constipation mouse model. MATERIALS/METHODS: To induce constipation, Lop (5 mg/kg) was administered orally to ICR mice twice a day for 4 days, and the dose was increased to 8 mg/kg after a 3-day rest period. Cheonggukjang (500 mg/kg, HTBC, or LTBC respectively) was administered for four weeks before the Lop treatment. RESULTS: The number of stools, fecal weight, water contents, gastrointestinal transit, and histological alterations were recovered significantly in the HTBC or LTBC groups. HTBC and LTBC administration did not induce significant changes in body weight, dietary intake, and behavior. The opioid-receptor downstream signaling pathway in colon tissues was also evaluated. The c-Kit, stem cell kinase, and mitogen-activated protein kinases subfamilies, including extracellular signal-regulated kinase 1/2, c-Jun N-terminal kinases, and p38, were all downregulated in the HTBC or LTBC-administered mice colon compared to the Lop group. CONCLUSION: These results show that Cheonggukjang, containing high levels of toxins and BAs, have a similar laxative effect in a mouse model of Lop-induced constipation.

• Journal of Plant Biotechnology
• /
• 제48권4호
• /
• pp.289-303
• /
• 2021

Covid-19 is an ongoing pandemic as we speak in 2022. This infectious disease is caused by the SARS-CoV-2 virus, which infects cells by binding to the angiotensin-converting enzyme 2 (ACE2) receptor on the cell surface. Thus, strategies that inhibit the binding of SARS-CoV-2 to the ACE2 receptor can stop this contagion. Hanjeli (Coix lacryma-jobi) essential oil contains many bioactive compounds, including dodecanoic acid; tetradecanoic acid; 7-Amino-8-imino-2-(2-imino-2H-chromen-3-yl); and 1,5,7,10-tetraaza-phen-9-one. These compounds suppress viral replication and may prevent Covid-19. Accordingly, this study assessed whether, these four limonoid compounds can block the ACE2 receptor. To this end, their physicochemical properties were predicted using Lipinski's "rule of five" on the SwissADME website, and their toxicity was assessed using the online tools ProTox and pkCSM. Additionally, their interactions with the ACE2 receptor were predicted via molecular docking using Autodock Vina. All the four compounds satisfied the "rule of five" and tetradecanoic acid was predicted to have a higher affinity than the comparison compound remdesivir and the original ligand of ACE2. Molecular docking results suggested that the compounds from hanjeli essential oil interact with the active site of the ACE2 receptor similarly as the original ligand and remdesivir. In conclusion, hanjeli essential oil contains compounds predicted hinder the interaction of SARS-CoV-2 with the ACE2 receptor. Accordingly, our data may facilitate the development of a phytomedical strategy against SARS-CoV-2 infection.

• Molecules and Cells
• /
• 제45권11호
• /
• pp.855-867
• /
• 2022

For proper function of proteins, their subcellular localization needs to be monitored and regulated in response to the changes in cellular demands. In this regard, dysregulation in the nucleocytoplasmic transport (NCT) of proteins is closely associated with the pathogenesis of various neurodegenerative diseases. However, it remains unclear whether there exists an intrinsic regulatory pathway(s) that controls NCT of proteins either in a commonly shared manner or in a target-selectively different manner. To dissect between these possibilities, in the current study, we investigated the molecular mechanism regulating NCT of truncated ataxin-3 (ATXN3) proteins of which genetic mutation leads to a type of polyglutamine (polyQ) diseases, in comparison with that of TDP-43. In Drosophila dendritic arborization (da) neurons, we observed dynamic changes in the subcellular localization of truncated ATXN3 proteins between the nucleus and the cytosol during development. Moreover, ectopic neuronal toxicity was induced by truncated ATXN3 proteins upon their nuclear accumulation. Consistent with a previous study showing intracellular calcium-dependent NCT of TDP-43, NCT of ATXN3 was also regulated by intracellular calcium level and involves Importin α3 (Imp α3). Interestingly, NCT of ATXN3, but not TDP-43, was primarily mediated by CBP. We further showed that acetyltransferase activity of CBP is important for NCT of ATXN3, which may acetylate Imp α3 to regulate NCT of ATXN3. These findings demonstrate that CBP-dependent acetylation of Imp α3 is crucial for intracellular calcium-dependent NCT of ATXN3 proteins, different from that of TDP-43, in Drosophila neurons.

• 대한본초학회지
• /
• 제24권4호
• /
• pp.87-93
• /
• 2009

Objectives : Aconiti Lateralis Preparata Radix (附子) and Aconiti Tuber (川烏) are not commonly prescribed, but are necessary for some clinical conditions, despite of the fact that some negative effects have been known to occur with these medicines. This study shows the consequences for aspartate aminotransferase (AST), alanine aminotransferase (ALT) due to herbal medicines, including Aconiti Lateralis Preparata Radix (附子) and Aconiti Tuber (川烏). Methods : From 1st June 2007 to 10th May 2009, the results were analyzed for 64 patients belonging to the OO Oriental Medical Hospital who took herbal medicine, including Aconiti Lateralis Preparata Radix (附子) and Aconiti Tuber (川烏), more than 20 days. This is the study about the comparison and the investigation of AST, ALT. And the results were taken upon their hospitalization and to their departure. The Criteria of Diagnosis in Liver Injury of CIOMS was used as a standard for their examinations. Results : AST, ALT (total 64). The number of patients who were within normal reference value : 49. The number of patients who exceed the normal reference value after dosage, without satisfying the Criteria of Diagnosis in Liver Injury : 5. The number of patients who were recovered in normal reference value after dosage : 9. The number of patients who satisfying the Criteria of Diagnosis in Liver Injury after dosage : 1. Conclusions : This results suggest that these herbal medicines, including Aconiti Lateralis Preparata Radix (附子) and Aconiti Tuber (川烏), didn't cause adverse side-effects on AST, ALT of the patients who are taking them.

• 대한본초학회지
• /
• 제24권4호
• /
• pp.173-179
• /
• 2009

Objectives : In this study, the effects of different fractions isolated from modified Boyanghwanotang(mBHT) extract on LPS-induced inflammation in BV2 microglial cells were investigated. Methods : mBHT was extracted with water, and then fractionated with n-hexane, methylene chloride, ethylacetate and n-butanol. BV2 cells, a mouse microglia line were incubated with different concentrations of each fraction of mBHT for 30 min, and then stimulated with LPS for 24 h. Cell toxicity was determined by MTT assay. The concentration of nitric oxide (NO) was measured in culture medium by Griess reagent assay. The expression of inducible nitric oxide synthease (iNOS) protein was determined by Western blot. Results : Four fractions of mBHT were significantly inhibited LPS-induced NO productions in BV2 cells in a dose-dependent manner. The methylene chloride fraction of mBHT was most strongly inhibited the NO production compared with those of the others. The methylene chloride fraction of mBHT was also suppressed LPS-induced iNOS expression comparison of other fractions at same concentration ($50\;{\mu}g/ml$) in BV2 cells. Conclusions : The results showed that the methylene chloride fraction of mBHT may have an strong anti-inflammatory property through the inhibition of NO production and iNOS expression in activated microglia, and could a therapeutic potential for the treatment of various brain inflammatory diseases.

• 한국산업보건학회지
• /
• 제25권1호
• /
• pp.58-71
• /
• 2015

Objectives: The aims of this study were to investigate the classification system of chemical substances in the Occupational Safety and Health Act(OSHA) and Chemical Substances Control Act(CSCA) and to compare several health indices (i.e., Time Weighted Average (TWA), Lethal Dose ($LD_{50}$), and Lethal Concentration ($LC_{50}$) of chemical substances by categories in each law. Methods: The chemicals regulated by each law were classified by the specific categories provided in the respective law; seven categories for OSHA (chemicals with OELs, chemicals prohibited from manufacturing, etc., chemicals requiring approval, chemicals kept below permissible limits, chemicals requiring workplace monitoring, chemicals requiring special management, and chemicals requiring special heath diagnosis) and five categories from the CSCA(poisonous substances, permitted substances, restricted substances, prohibited substances, and substances requiring preparation for accidents). Information on physicochemical properties, health indices including CMR characteristics, $LD_{50}$ and $LD_{50}$ were searched from the homepages of the Korean Occupational and Safety Agency and the National Institute of Environmental Research, etc. Statistical analysis was conducted for comparison between TWA and health index for each category. Results: The number of chemicals based on CAS numbers was different from the numbers of series of chemicals listed in each law because of repeat listings due to different names (e.g., glycol monoethylether vs. 2-ethoxy ethanol) and grouping of different chemicals under the same serial number(i.e., five different benzidine-related chemicals were categorized under one serial number(06-4-13) as prohibited substances under the CSCA). A total of 722 chemicals and 995 chemicals were listed at the OSHA and its sub-regulations and CSCA and its sub-regulations, respectively. Among these, 36.8% based on OSHA chemicals and 26.7% based on CSCA chemicals were regulated simultaneously through both laws. The correlation coefficients between TWA and $LC_{50}$ and between TWA and $LD_{50}$, were 0.641 and 0.506, respectively. The geometric mean values of TWA calculated by each category in both laws have no tendency according to category. The patterns of cumulative graph for TWA, $LD_{50}$, $LC_{50}$ were similar to the chemicals regulated by OHSA and CCSA, but their median values were lower for CCSA regulated chemicals than OSHA regulated chemicals. The GM of carcinogenic chemicals under the OSHA was significantly lower than non-CMR chemicals($2.21mg/m^3$ vs $5.69mg/m^3$, p=0.006), while there was no significant difference in CSCA chemicals($0.85mg/m^3$ vs $1.04mg/m^3$, p=0.448). $LC_{50}$ showed no significant difference between carcinogens, mutagens, reproductive toxic chemicals and non-CMR chemicals in both laws' regulated chemicals, while there was a difference between carcinogens and non-CMR chemicals in $LD_{50}$ of the CSCA. Conclusions: This study found that there was no specific tendency or significant difference in health indicessuch TWA, $LD_{50}$ and $LC_{50}$ in subcategories of chemicals as classified by the Ministry of Labor and Employment and the Ministry of Environment. Considering the background and the purpose of each law, collaboration for harmonization in chemical categorizing and regulation is necessary.

• Journal of Pharmaceutical Investigation
• /
• 제26권2호
• /
• pp.71-82
• /
• 1996

This study has been undertaken to evaluate hydrophobic cyclodextrin(CD) derivatives as a sustained release carrier of azidothymidine(AZT), AZT, which has potent activity against AIDS and AIDS-related complex as thymidine analogue, has been reported that it has significant toxicity and short half life. Therefore, it is necessary to design sustained release oral dosage form to avoid undesirable side effects attributable to an excessive plasma concentration and to reduce the frequency of administration of AZT. Inclusion complexes of AZT with $acetyl-{\beta}-cyclodextrin\;(AC{\beta}CD)$ and $triacetyl-{\beta}-cyclodextrin(TA{\beta}CD)$ were prepared by solvent evaporation method. Interactions of AZT with CD were investigated by Differential Scanning Calorimetry(DSC) and Infrared Spectrophotometry(IR). The decreasing order of water solubilities of AZT and AZT-CD inclusion complexes were as follows; $AZT\;(27.873{\pm}0.015,mg/ml)\;>\;AZT-AC{\beta}CD\;(3.377{\pm}0.003)\;>\;AZT-TA{\beta}CD\;(2.528{\pm}0.001)$. Partition coefficients of $AZT-AC{\beta}CD\;and;\AZT-TA{\beta}CD$ inclusion complexes were increased by 1.27-fold, 1.54-fold in pH 1.2 and 1.32-fold, 1.47-fold in pH 6.8 in comparison with that of AZT. The mean dissolution time (MDT, min) which represents the rapidity of dissolution rate of AZT, $AZT-AC{\beta}CD,\;AZT-TA{\beta}CD$ were 5.12, 14.02 and 19.38 min in pH 1.2 and 2.52, 15.19 and 18.19 min in pH 6.8. AZT was very rapidly and completely dissolved in pH 1.2 and pH 6.8 within 5 minutes. But AZT-CD inclusion complexes showed the sustained release pattern in comparison with AZT alone. The simultaneous in situ nasal and jejunal recirculation study to compare the intrinsic absorptivity and the property of absorption sites revealed that the absorption of $AZT-TA{\beta}CD\;(N:35.35{\pm}1.08%,\;J:27.47{\pm}1.18%)$ was more than that of $AZT\;(N:16.89{\pm}2.25%,\;J:15.86{\pm}2.33%)$. The above results suggest that $TA{\beta}CD$ which is a hydrophobic cyclodextrin may serve as sustained release carrier with absorption enhancing effect.