• Journal of Dairy Science and Biotechnology
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• v.37 no.1
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• pp.15-26
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• 2019

A common belief is that human milk is sterile. However, the development of culture-independent molecular methods, especially Next Generation Sequencing, has revealed that human milk harbors diverse and rich bacterial communities. Although studies aimed at characterizing the microbiota of human milk have produced different findings, Staphylococcus and Streptococcus are presumed to be normal members of the microbiota. Factors that influence variation in the microbiota are unclear; however, the postpartum time, route of delivery, maternal obesity, and health status may be influential. The origin of the microbiota is a hotly debated topic. Human milk bacteria are thought to be introduced through bacterial exposure of the mammary duct during breast feeding and/or the entero-mammary pathway from the maternal gastrointestinal tract. Although the exact mechanism related to the entero-mammary pathway is unknown, it is presumed that bacteria penetrate the intestinal epithelium and then migrate to the mammary gland, dendritic cells, and macrophages. In this review, various relevant studies are introduced.

• Tuberculosis and Respiratory Diseases
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• v.85 no.3
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• pp.221-226
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• 2022

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation due to chronic airway inflammation and destruction of the alveolar structure from persistent exposure to oxidative stress. The body has various antioxidant mechanisms for efficiently coping with such oxidative stress. The nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) is a representative system. Dysregulation of the Nrf2-ARE pathway is responsible for the development and promotion of COPD. Furthermore, COPD severity is also closely related to this pathway. There has been a clinical impetus to use Nrf2 for diagnostic and therapeutic purposes. Therefore, in this work, we systematically reviewed the clinical significance of Nrf2 in COPD patients, and discuss the value of Nrf2 as a potential COPD biomarker.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.1
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• pp.38-47
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• 2011

This study focused on health risk assessment via multi-routes of As exposure to establish a target cleanup level (TCL) in abandoned mines. Soil, ground water, and rice samples were collected near ten abandoned mines in November 2009. The As contaminations measured in all samples were used for determining the probabilistic health risk by Monte-Carlo simulation techniques. The human exposure to As compound was attributed to ground water ingestion. Cancer risk probability (R) via ground water and rice intake exceeded the acceptable risk range of $10^{-6}{\sim}10^{-4}$ in all selected mines. In particular, the MB mine showed the higher R value than other mines. The non-carcinogenic effects, estimated by comparing the average As exposure with corresponding reference dose were determined by hazard quotient (HQ) values, which were less than 1.0 via ground water and rice intake in SD, NS, and MB mines. This implied that the non-carcinogenic toxic effects, due to this exposure pathway had a greater possibility to occur than those in other mines. Besides, hazard index (HI) values, representing overall toxic effects by summed the HQ values were also greater than 1.0 in SD, NS, JA, and IA mines. This revealed that non-carcinogenic toxic effects were generally occurred. The As contaminants in all selected mines exceeded the TCL values for target cancer risk ($10^{-6}$) through ground water ingestion and rice intake. However, the As level in soil was greater than TCL value for target cancer risk via inadvertent soil ingestion pathway, except for KK mine. In TCL values for target hazard quotient (THQ), the As contaminants in soil did not exceed such TCL value. On the contrary, the As levels in ground water and polished rice in SD, NS, IA, and MB mines were also beyond the TCL values via ground water and rice intake. This study concluded that the health risks through ground water and rice intake were greater than those though soil inadvertent ingestion and dermal contact. In addition, it suggests that the abandoned mines to exceed the risk-based TCL values are carefully necessary to monitor for soil remediation.

• Journal of Soil and Groundwater Environment
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• v.12 no.1
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• pp.97-102
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• 2007

An environmental survey from three abandoned metal mine areas was undertaken on to assess the risk of adverse health effects on human exposure to heavy metals influenced by past mining activities. Tailings contained high concentrations of heavy metals may have a impact on soils and waters around the tailing piles. In order to perform the human risk assessment, chemical analysis data of soils, rice grains and waters for As, Cd, Cu and Pb have been used. The HQ values for heavy metals via the rice consumption were significantly higher compared with other exposure pathways in all metal mine areas. The resulting HI values in three mine areas were higher than 9.0, and their toxic risk due to rice ingestion was strong in these mine areas. The cancer risk of being exposed to As by the rice consumption from the A, B and C mine areas was $5.1\;{\times}\;10^{-3}$, $6.8\;{\times}\;10^{-3}$ and $3.1\;{\times}\;10^{-3}$, respectively. The As cancer risk via the exposure pathway of rice ingestion from these mine areas exceeds the acceptable risk of 1 in 10,000 set for regulatory purposes. Thus, the daily intakes of rice by the local residents from these mine areas can pose a potential health threat if exposed by long-term As exposure.

• Journal of Soil and Groundwater Environment
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• v.25 no.3
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• pp.65-73
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• 2020

Exposure assessment methodology for outdoor air inhalation pathways (i.e., inhalation of volatile compounds and fugitive dust in outdoor air) was investigated. Default values of several parameters currently used in Korea (e.g., Q/C; inverse value of concentration per unit flux, and frs; soil fraction in PM10) may not be suitable and lack site-specificity, as they have been adopted from the risk assessment guidance of the United States or the Netherlands. Such limitation can be addressed to a certain degree by incorporating the volatilization factor (VF) and the particulate emission factor (PEF) with Box model. This approach was applied to an exposure assessment of a site contaminated with petroleum hydrocarbons in Korea. The result indicated that the suggested methodology led to more accurate site-specific exposure assessment for outdoor inhalation pathways. Further work to establish methodology to determine site-specific Q/C values in Korea needs to be done to secure the reliability of the exposure assessment for outdoor air inhalation pathways.

• Environmental Engineering Research
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• v.13 no.2
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• pp.73-78
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• 2008

For a given soil-contaminated site, a level of soil contamination is characterized and decisions on risk may be made from the risk assessment. The study evaluated critical design factors for the determination of sample size in the sampling design plan and the assessment of soil contaminant- leaching to groundwater. Two variables, the minimum relative detectable difference (T) and coefficient of variation (CV) were evaluated for the sample size determination. The minimum number of samples can be appropriately determined by CV under a T value greater than or equal to 0.2. Soil-contaminant leaching to groundwater was evaluated by using the Soil Screening Level equation of U.S. Environmental Protection Agency and the Risk Based Screening Level equation of American Society for Testing and Materials, with the same input parameters. The groundwater concentrations estimated from soil contaminant concentrations were significantly affected by the Darcy velocity of groundwater and the organic content of soil.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.923-931
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• 2013

Rapamycin, known as an inhibitor of Target of Rapamycin (TOR), is an immunosuppressant drug used to prevent rejection in organ transplantation. Despite the close association of the TOR signaling cascade with various scopes of metabolism, it has not yet been thoroughly investigated at the metabolome level. In our current study, we applied mass spectrometric analysis for profiling primary metabolism in order to capture the responsive dynamics of the Chlamydomonas metabolome to the inhibition of TOR by rapamycin. Accordingly, we identified the impact of the rapamycin treatment at the level of metabolomic phenotypes that were clearly distinguished by multivariate statistical analysis. Pathway analysis pinpointed that inactivation of the TCA cycle was accompanied by the inhibition of cellular growth. Relative to the constant suppression of the TCA cycle, most amino acids were significantly increased in a time-dependent manner by longer exposure to rapamycin treatment, after an initial down-regulation at the early stage of exposure. Finally, we explored the isolation of the responsive metabolic factors into the rapamycin treatment and the culture duration, respectively.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.05a
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• pp.78-78
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• 2002

• Nutrition Research and Practice
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• v.16 no.3
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• pp.330-343
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• 2022

BACKGROUND/OBJECTIVES: Zanthoxylum schinifolium is traditionally used as a spice for cooking in East Asian countries. This study was undertaken to evaluate the anti-proliferative potential of ethanol extracts of Z. schinifolium leaves (EEZS) against human bladder cancer T24 cells. MATERIALS/METHODS: Subsequent to measuring the cytotoxicity of EEZS, the anti-cancer activity was measured by assessing apoptosis induction, reactive oxygen species (ROS) generation, and mitochondrial membrane potential (MMP). In addition, we determined the underlying mechanism of EEZS-induced apoptosis through various assays, including Western blot analysis. RESULTS: EEZS treatment concentration-dependently inhibited T24 cell survival, which is associated with apoptosis induction. Exposure to EEZS induced the expression of Fas and Fas-ligand, activated caspases, and subsequently resulted to cleavage of poly (ADP-ribose) polymerase. EEZS also enhanced the expression of cytochrome c in the cytoplasm by suppressing MMP, following increase in the ratio of Bax:Bcl-2 expression and truncation of Bid. However, EEZS-mediated growth inhibition and apoptosis were significantly diminished by a pan-caspase inhibitor. Moreover, EEZS inhibited activation of the phosphoinositide 3-kinase (PI3K)/Akt pathway, and the apoptosis-inducing potential of EEZS was promoted in the presence of PI3K/Akt inhibitor. In addition, EEZS enhanced the production of ROS, whereas N-acetyl cysteine (NAC), a ROS scavenger, markedly suppressed growth inhibition and inactivation of the PI3K/Akt signaling pathway induced by EEZS. Furthermore, NAC significantly attenuated the EEZS-induced apoptosis and reduction of cell viability. CONCLUSIONS: Taken together, our results indicate that exposure to EEZS exhibits anti-cancer activity in T24 bladder cancer cells through ROS-dependent induction of apoptosis and inactivation of the PI3K/Akt signaling pathway.

• Archives of Pharmacal Research
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• v.21 no.2
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• pp.113-119
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• 1998

Changes in the release and uptake of glutamate in cerebellar granule and glial cells of offspring of lead-exposed mothers were determined. In cultured cerebellar granule cells exposed to lead for 5 days, glutamate release was less influenced upon N-methyl-D-aspartate (NMDA) stimulation than that in the control. Although the NMDA-stimulated release of glutamate in cerebellar granule cells prepared from lead-exposed first generation pups was not different from that of the control group, the S-nitroso-N-acetylpenicillamine (SNAP)-stimulated release of glutamate in cerebellar granule cells obtained from lead-treated pups was less elevated than that in the control. Furthermore, in cerebellar granule cells obtained from lead-exposed second generations pups, glutamate release did not respond to both NMDA and SNAP stimulation. In cerebellar glial cells exposed to lead, the basal glutamate uptake was not changed. However, the L-trans-pyrollidine-2,4-dicarboxylic acid (PDC)-blocking effects was significantly reduced. In glial cells obtained from lead-exposed pups, the glutamate uptake was also less blocked by PDC than that in the control. Further decreases in PDC-blocking effects were observed in cerebellar glial cells obtained from lead-treated second generation pups compared to those from the control group. These results indicate that lead exposure induces the changes in the sensitivities of the glutamate release and uptake transporter. In addition, these results suggest that lead exposure might affect the intracellular signalling pathway and transmission in glutamatergic nervous system.