• Natural Product Sciences
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• v.22 no.4
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• pp.246-251
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• 2016

This study investigated the effects of (-)-sesamin on memory deficits in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned mouse model of Parkinson's disease (PD). MPTP lesion (30 mg/kg/day, 5 days) in mice showed memory deficits including habit learning memory and spatial memory. However, treatment with (-)-sesamin (25 and 50 mg/kg) for 21 days ameliorated memory deficits in MPTP-lesioned mouse model of PD: (-)-sesamin at both doses improved decreases in the retention latency time of the passive avoidance test and the levels of dopamine, norepinephrine, 3,4-dihydroxyphenylacetic acid, and homovanillic acid, improved the decreased transfer latency time of the elevated plus-maze test, reduced the increased expression of N-methyl-D-aspartate (NMDA) receptor, and increased the reduced phosphorylation of extracellular signal-regulated kinase (ERK1/2) and cyclic AMP-response element binding protein (CREB). These results suggest that (-)-sesamin has protective effects on both habit learning memory and spatial memory deficits via the dopaminergic neurons and NMDA receptor-ERK1/2-CREB system in MPTP-lesioned mouse model of PD, respectively. Therefore, (-)-sesamin may serve as an adjuvant phytonutrient for memory deficits in PD patients.

• Journal of ILASS-Korea
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• v.17 no.3
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• pp.146-151
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• 2012

This study was primarily focused on the experimental comparison of the particle emission characteristics for heavy duty engine. PM and particle number from various heavy duty engines and DPF type were analyzed with a golden particle measurement system recommended by the Particle Measurement Program. And the repeatability and reproducibility between test mode was analyzed. This study was conducted for the experimental comparison on particulate emission characteristics between the European and World-Harmonized test cycles for a heavy-duty diesel engine. To verify the particulate mass and particle number concentrations from various operating modes, ETC/ESC and WHTC/WHSC, both of which will be enacted in Euro VI emission legislation, were evaluated. Real-time particle formation of the transient cycles ETC and WHTC were strongly correlated with engine operating conditions and after-treatment device temperature. A higher particle number concentration during the ESC mode was ascribed to passive DPF regeneration and the thermal release of low volatile particles at high exhaust temperature conditions.

• Biomolecules & Therapeutics
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• v.9 no.2
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• pp.88-95
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• 2001

(+)-Methamphetamine (METH) is a psychostimulant, which has been the most popular abused drug in Korea. The rewarding mechanism in METH abuse has been reported to be mediated by dopaminergic system. Recently, it has been reported that dopamine releaser (phentermine) plays a dominant role in the discriminative stimulus effects of METH, whereas 5-HT releaser (fenfluramine) can strongly modify METH self-administration. The present study is designed to assess the behavioral changes and the changes of the serotonin receptors in the brains of rats administered repeated of self-administered METH. The repeated administration of 1.0 mg/kg/day METH for 12 days increased locomotor activities, and there was no difference between i.v. and i.p. treatment. Rats had actively acquired METH self-administration for 3 weeks at 0.1 or 0.2 mg/kg/injection. Whereas, it was taken few days to acquire sucrose pellet self-administration. The binding of [$^3$H]-8-hydroxy-DPAT (5-H $T_{1A}$ receptors) and [$^3$H]-5-carboxytryptamine (5-H $T_{1B}$ receptors) to brain sections was examined. Both passive administration and self-administration of METH did not change significantly the serotonin receptors levels in hippocampus, striatum and nucleus accumbens. These results suggest that serotonin receptors may not change in the acquisition period of METH self-administration, and we are trying to investigate the serotonin receptors levels of brain in rats maintained of METH self-administration.n.n.

• Economic and Environmental Geology
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• v.56 no.4
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• pp.409-419
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• 2023

Acid mine drainage(AMD) treatment is classified as both passive and active treatment. During the treatment, about 5,000 tons of neutralization sludge is generated as a by-product per year in Korea. This study was conducted to evaluate the characteristics of sludge generated from physico·chemical treatment processes as an active treatment from 5 different sources (D, H, S, T, Y) and the possibility of the sludges being recycled. The sludges have a pH range of 5.86 ~ pH 7.89, and a water content range of 51% ~ 82%. Most of particle sizes were less than 25 ㎛. In analysis of inorganic elements, the concentration of Al, Fe, and Mn were between 1,189 mg/kg ~ 129,344 mg/kg, 106,132 mg/kg ~ 338,011 mg/kg, and 3,472 mg/kg ~ 11,743 mg/kg, respectively. The concentration of As and Zn in sludge-T, Cd in sludge-D, Ni in sludge-H, Zn in sludge-S, and Cd in sludge-Y exceeded the soil contamination standards of Korea. The results from 2 separate kinds of leaching test, the Korea Standard Leaching Test(KSLT) and Toxicity Characteristic Leaching Procedure(TCLP), showed that all the sludges met the Korea groundwater standards. From the XRD and SEM-EDS analysis, the peaks of calcite and quartz were found in the sludges. The sludge also had a high proportion of Fe and O, and the majority of the composition was amorphous iron hydroxide.

• The Journal of the Korea Contents Association
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• v.11 no.7
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• pp.298-305
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• 2011

The purpose of this dissertation is finding the meaning and form of Euthanasia, Considering by Criminal law that the core of the debate over the 'pros and cons' of euthanasia, And seeking measures about needs of currently Euthanasia legislation and institutional establishment. Through the remarkable progress, today's medical science makes to cure the Incurable patients, and artificially prolong human life by life-support system. These changes of Healthcare Environments extending a permissible range of Euthanasia over the series of criminal discussions about Euthanasia. And medical treatment has been discussed from negative side to positive side. So, In the current legal system, seeking for realistic measure is demands of the times behind the penally and ethical problems. Therefore, I will study the needs of legal system and reestablish values about Respect for Human Life.

• Journal of Korean Society on Water Environment
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• v.27 no.2
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• pp.167-177
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• 2011

Billions of barrels of briny produced water are generated in the United States every year during oil and gas production. The first step toward recovering or reusing this water is to remove the hazardous organics dissolved in the briny produced water. Biological degradation of hazardous volatile compound could be possible regardless of salinity if they were extracted from briny water. In the current work, the effectiveness of a vapor phase biofilter to degrade the gas-phase contaminants (benzene, toluene, ethylbenzene and xylenes, BTEX) extracted from briny produced water was evaluated. The performance of biofilter system responded well to short periods when the BTEX feed to the biofilter was discontinued. To challenge the system further, the biofilter was subjected to periodic spikes in inlet BTEX concentration as would be expected when it is coupled to a Surfactant-Modified Zeolite (SMZ) bed. Results of these experiments indicate that although the BTEX removal efficiency declined under these conditions, it stabilized at 75% overall removal even when the biofilter was provided with BTEX-contaminated air only 8 hours out of every 24 hours. Benzene removal was found to be the most sensitive to time varying loading conditions. A passive, granular activated carbon bed was effective at attenuating and normalizing the peak BTEX loadings during SMZ regeneration over a range of VOC loads. Field testing of a SMZ bed coupled with an activated carbon buffering/biofilter column verified that this system could be used to remove and ultimately biodegrade the dissolved BTEX constituents in briny produced water.

• Physical Therapy Korea
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• v.21 no.1
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• pp.47-54
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• 2014

The aim of this study was to compare the duration of hamstring flexibility improvement after 3 stretching interventions in people with limited hamstring flexibility. Twenty-two subjects (12 men, 10 women) with limited hamstring flexibility of the dominant leg received 3 stretching interventions- modified dynamic stretching (MDS), hold-relax (HR), and static stretching (SS)-in a random order. All the subjects received all 3 interventions at intervals of at least 24 hours to minimize any carry-over effect. Modified dynamic stretching was applied as a closed kinetic chain exercise in the supine position by using the sling suspension system (Redcord Trainer(R)). The SS and HR interventions were individually performed in the straight leg raising (SLR) position, and all 3 interventions were performed for 3 minutes. Outcome measures included passive knee extension (PKE) measurements. Five post-test measurements were recorded for all subjects at 3, 6, 9, 15, and 30 minutes after the interventions. MDS was associated with a significant increase in knee extension range of motion even at 30 minutes post-treatment. In contrast, the HR and SS stretching methods showed increased hamstring flexibility for only 6 minutes post-treatment. Improvements in the range of motion of knee extension (indicating enhancement in hamstring flexibility) with MDS were maintained longer than those with the HR and SS interventions. Therefore, MDS may be more effective than the other interventions for maintaining hamstring flexibility.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.1
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• pp.37-47
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• 2011

This study was aimed to investigate the memory enhancing effect of Jeongjihwan against scopolamine-induced amnesia in C57BL/6 mice. To determine the effect of Jeongjihwan on the memory and cognitive function, we have injected scopolamine (1 mg/kg, i.p.) into C57BL/6 mice 30 min before beginning of behavior tests. We have conducted Y-maze, Morris water-maze, passive avoidance and fear conditioning tests to compare learning and memory functions. Scopolamine-induced behavior changes of memory impairment were significantly restored by oral administration of Jeongjihwan (100 or 200 mg/kg/day). To elucidate the molecular mechanism underlying the memory enhancing effect of Jeongjihwan, we have examined the antioxidant defense system and neurotrophic factors. Jeongjihwan treatment attenuated intracellular accumulation of reactive oxygen species and up-regulated mRNA and protein expression of antioxidant enzymes as assessed by RT-PCR and western blot analysis, respectively. Jeongjihwan also increased protein levels of brain-derived neurotrophic factor (BDNF) compared with those in the scopolamine-treated group. Furthermore, as an upstream regulator, the activation of cAMP response element-binding protein (CREB) via phosphorylation was assessed by Western blot analysis. Jeongjihwan elevated the phosphorylation of CREB (p-CREB), which seemed to be mediated partly by extracellular signal-regulated kinase1/2 (ERK1/2) and protein kinase B/Akt. These findings suggest that Jeongjihwan may have preventive and therapeutic potential in the management of amnesia.

• Restorative Dentistry and Endodontics
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• v.36 no.3
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• pp.180-187
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• 2011

Introduction: Eliminating the residual debris and bacteria in the root canal system is one of the main purposes of the endodontic treatment. However, the complexity on the anatomy of the root canal system makes it difficult to eliminate the bacterial biofilm existing along the root canal surface and necrotic pulp tissue by mechanical instrumentation and chemical irrigation. Recently, more effective irrigant delivery systems for root canal irrigation have been developed. The purpose of this review was to present an overview of root canal irrigant delivery techniques and devices available in endodontics. Review: The contents of this paper include as follows; - syringe-needle irrigation, manual dynamic irrigation, brushes - sonic and ultrasonic irrigation, passive ultrasonic irrigation, rotary brush, RinsEndo, EndoVac, Laser Conclusion: Though technological advances during the last decade have brought to fruition new agitation devices that rely on various mechanisms, there are few evidence based study to correlate the clinical efficacy of these devices with improved outcomes except syringe irrigation with needle and ultrasonic irrigation. The clinicians should try their best efforts to deliver antimicrobial and tissue solvent solutions in predictable volumes safely to working length.

• Journal of Microbiology and Biotechnology
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• v.21 no.8
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• pp.874-883
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• 2011

Many studies have shown that the steamed root of Rehmannia glutinosa (SRG), which is widely used in the treatment of various neurodegenerative diseases in the context of Korean traditional medicine, is effective for improving cognitive and memory impairments. The purpose of this study was to examine whether SRG extracts improved memory defects caused by administering scopolamine (SCO) into the brains of rats. The effects of SRG on the acetylcholinergic system and proinflammatory cytokines in the hippocampus were also investigated. Male rats were administered daily doses of SRG (50, 100, and 200 mg/kg, i.p.) for 14 days, 1 h before scopolamine injection (2 mg/kg, i.p.). After inducing cognitive impairment via scopolamine administration, we conducted a passive avoidance test (PAT) and the Morris water maze (MWM) test as behavioral assessments. Changes in cholinergic system reactivity were also examined by measuring the immunoreactive neurons of choline acetyltransferase (ChAT) and the reactivity of acetylcholinesterase (AchE) in the hippocampus. Daily administration of SRG improved memory impairment according to the PAT, and reduced the escape latency for finding the platform in the MWM. The administration of SRG consistently significantly alleviated memory-associated decreases in cholinergic immunoreactivity and decreased interleukin-$1{\beta}$ (IL-$1{\beta}$) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) mRNA expression in the hippocampus. The results demonstrated that SRG had a significant neuroprotective effect against the neuronal impairment and memory dysfunction caused by scopolamine in rats. These results suggest that SRG may be useful for improving cognitive functioning by stimulating cholinergic enzyme activities and alleviating inflammatory responses.