• The Korean Journal of Physiology and Pharmacology
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• 제22권5호
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• pp.525-538
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• 2018

Post-traumatic stress disorder (PTSD) is a trauma-induced psychiatric disorder characterized by impaired fear extermination, hyperarousal, and anxiety that may involve the release of monoamines in the fear circuit. The reported pharmacological properties of tetramethylpyrazine (TMP) include anti-cancer, anti-diabetic, anti-atherosclerotic, and neuropsychiatric activities. However, the anxiolytic-like effects of TMP and its mechanism of action in PTSD are unclear. This study measured several anxiety-related behavioral responses to examine the effects of TMP on symptoms of anxiety in rats after single prolonged stress (SPS) exposure by reversing the serotonin (5-HT) and hypothalamic-pituitary-adrenal (HPA) axis dysfunction. Rats were given TMP (10, 20, or 40 mg/kg, i.p.) for 14 days after SPS exposure. Administration of TMP significantly reduced grooming behavior, increased the time spent and number of visits to the open arm in the elevated plus maze test, and significantly increased the number of central zone crossings in the open field test. TMP administration significantly reduced the freezing response to contextual fear conditioning and significantly restored the neurochemical abnormalities and the SPS-induced decrease in 5-HT tissue levels in the prefrontal cortex and hippocampus. The increased 5-HT concentration during TMP treatment might be partially attribute to the tryptophan and 5-hydroxyindoleacetic acid mRNA level expression in the hippocampus of rats with PTSD. These findings support a role for reducing the altered serotonergic transmission in rats with PTSD. TMP simultaneously attenuated the HPA axis dysfunction. Therefore, TMP may be useful for developing an agent for treating psychiatric disorders, such those observed in patients with PTSD.

• Archives of Plastic Surgery
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• 제35권2호
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• pp.121-126
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• 2008

Purpose: Poly-N-acetyl glucosamine(PGlcNAc) nanofiber-based materials, produced by a marine microalga, have been characterized as effective hemostatic and angiogenic agents. The similarity between PGlcNAc patch and the natural extracellular matrix allows it to support new healthy tissue growth in an injured area and to encourage fluid absorption. In this study, we hypothesized that a poly-N-acetyl glucosamine fiber patch(PGlcNAc patch) may enhance wound healing in the db/db mouse. Methods: PGlcNAc patches were applied on one square centimeter, full-thickness, skin wounds in the db/db mouse model. Wounds(n=15 per group) were dressed with a PGlcNAc nanofiber patch for 1 hour(1 h), 24 hours(24 h) or left untreated(NT). After the application time, patches were removed and wounds were allowed to heal spontaneously. The rate of wound closure was evaluated by digital analysis of unclosed wound area in course of time. At day 10, wounds(n=7 per group) were harvested and quantified with immunohistochemical markers of proliferation(Ki-67) and vascularization (platelet endothelial cell adhesion molecule, PECAM-1). Results: Wounds dressed with PGlcNAc patches for 1 hour closed faster than control wounds, reaching 90% closure in 16.6 days, nine days faster than untreated wounds. Granulation tissue showed higher levels of proliferation and vascularization following 1 h treatment than the 24 h and NT groups. In addition to its hemostatic properties, the PGlcNAc material also appears to accelerate wound closure in healing-impaired genetically diabetic mice. Conclusion: This material, with its combination of hemostatic and wound healing properties, has the potential to be effective agent for the treatment of complicated wounds.

• 동의생리병리학회지
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• 제22권5호
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• pp.1240-1249
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• 2008

Kamigingansikpung-tang(KGST) has been used for many years as a therapeutic agent for acute stage of cerebrovascular disease and hypertension in oriental medicine. But the effect of KGST on hypertension and vascular system is not well-known. This study was done to investigate the effects of KGST on hypertension. The results were obtained as follow: KGST showed scavenging activity on DPPH free radical. KGST showed the inhibitory effect on ROS and ACE, and the accelerated SOD activity. KGST significantly decreased the blood pressure and pulse in DOCA-salt induced hypertensive rat. KGST significantly decreased the levels of aldosterone in DOCA-salt induced hypertensive rat. KGST significantly decreased the levels of dopamine, epinephrine in DOCA-salt induced hypertensive rat. KGST significantly decreased the levels of potassium(K+) and chloride(Cl-) in DOCA-salt induced hypertensive rat. KGST significantly decreased the levels of uric acid and creatine in DOCA-salt induced hypertensive rat. KGST has an effect on inhibiting cell damage of the heart, liver, kidney, and adrenal gland. results suggest that KGST might be effective in treatment and prevention of hypertension.

• Biomolecules & Therapeutics
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• 제21권4호
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• pp.313-322
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• 2013

Previous studies have demonstrated that repeated administration of the exogenous stress hormone corticosterone (CORT) induces dysregulation in the hypothalamic-pituitary-adrenal (HPA) axis and results in depression and anxiety. The current study sought to verify the impact of catechin (CTN) administration on chronic CORT-induced behavioral alterations using the forced swimming test (FST) and the elevated plus maze (EPM) test. Additionally, the effects of CTN on central noradrenergic systems were examined by observing changes in neuronal tyrosine hydroxylase (TH) immunoreactivity in rat brains. Male rats received 10, 20, or 40 mg/kg CTN (i.p.) 1 h prior to a daily injection of CORT for 21 consecutive days. The activation of the HPA axis in response to the repeated CORT injections was confirmed by measuring serum levels of CORT and the expression of corticotrophin-releasing factor (CRF) in the hypothalamus. Daily CTN administration significantly decreased immobility in the FST, increased open-arm exploration in the EPM test, and significantly blocked increases of TH expression in the locus coeruleus (LC). It also significantly enhanced the total number of line crossing in the open-field test (OFT), while individual differences in locomotor activities between experimental groups were not observed in the OFT. Taken together, these findings indicate that the administration of CTN prior to high-dose exogenous CORT significantly improves helpless behaviors, possibly by modulating the central noradrenergic system in rats. Therefore, CTN may be a useful agent for the treatment or alleviation of the complex symptoms associated with depression and anxiety disorders.

• 정보와 통신
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• 제11권6호
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• pp.37-54
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• 1994

멀티미디어 기술의 획기적 발전으로 이를 응용한 다양한 서비스가 개발되고 있다. 본 논문에서는 멀티미디어 응용 서비스를 TV, 컴퓨터, 통신, 주변기기, 소프트웨어 계열로 분류하고 설명하였다. 이중 컴퓨터 부분에서 멀티미디어 서비스를 중점적으로 설명하며 이러한 서비스가 제공되기 위한 시스템의 주요 서브시스템으로서 멀티미디어 데이터 처리를 위한 초고속 통신망, 운영체제, 지능형 에이젼트에 대한 논의를 하였다. 이중 특히 멀티미디어 운영체제 기술은 종합 멀티미디어 서비스 제공을 위한 하부 구조로서 최근 가장 활발히 발전되고 잇는 분야이다. 이에 본 논문에서는 일반적인 멀티미디어 운영체제의 발전방향 및 현재 개발 완료된 COSMOS 멀티미디어 그룹표현용 운영체제에 관한 설명을 한다. COSMOS의 특성, 모델, 추상적 데이터 구조에 관한 논의와 더불어 COSMOS상에서 개발된 3자간 영상회의시스템의 성능분석을 통하여 COSMOS와 같은 운영체제를 통한 멀티미디어 운영체제의 제공이 멀티미디어 서비스 환경변화를 주도함을 설명하였다.

• 한국수정란이식학회지
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• 제4권1호
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• pp.1-13
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• 1989

This paper reviews the most important steps that have generated consistent progress in principles and developmental progress of embryo cryopreservation, and also study on freezing procedure and its application by conventional method and current improved method for freezing procedure and its appilcation of embryo cryopreservation in farm animals. Four were of particular interest: 1.The transport of water across the ccli membrane (zona pellucida) during freezing and thawing accordinglyplays a role in determing whether the celi survives. This movement of water is controlied mainly by extracellular phase changes and by the nature and concentration of any cryoprotective agent present. Therates of cooling, freezing and warming, and the intervals over which they are applied are further decisi've factors in determining whether a cryopreservation procedure allows survival after thawing. 2.The first successful deep freezing experiments with sheep morula and blastocysts during the seventies were based on the early procedures used for mouse embryos.Current research during the eighties is developed with the aim of simplifying and improving current procedures such as one-step dilution and rapid or ultra-rapid cooling by using the model of laboratory animals. 3.The conventional method for the embryo cryopreservation is described. An alternative to this method which may result in high survival and also in reducing of the freezing and thawing time is done by combing a permeable cryoprotectant such as glycerol, DMSO or propanediol and a non-permeable compound such as sucrose, trehalose, raffinose or lactose. 4.Finally a different approach to the preservation of embryos, named vitrification, is introduced. This procedure depends upon the ability of concentrated solutions of cryoprotective agents such as glycerol and propanediol to supercool to very low temperature (-196$^{\circ}C$) during rapid cooling before solidifying without formation of ice. However, more complete data are necessary for successful vitrification of blastocysts.

• 한국화재소방학회논문지
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• 제28권6호
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• pp.41-46
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• 2014

계단에서의 합류는 건물 피난해석에서 매우 중요한 요소이다. 건물에서의 대규모 피난인이 이동하는 경우 정체가 발생하게 되는 지점은 병목현상이 발생하는 문이나 공간이 좁아지는 지점이 있다. 또한 계단에서의 정체이다. 계단에서의 정체는 상부층에서 내려오는 인원과 연결층에서 진입하려는 인원이 합류하면서 발생된다. 이러한 현상은 초고층 건물일 경우 더욱 심하게 될 것이다. 이러한 현상에 대해 현재 시뮬레이션의 결과에 의존하고 있다. 하지만, 이러한 모사가 정확하게 실제와 같이 구현되는지는 실험과의 비교를 통해 검토해볼 필요가 있다. 본 연구에서는 계단에서의 합류에 대한 실험과 시뮬레이션 적용분석을 수행하고 그 결과를 비교해보았다. 실제 실험과 시뮬레이션의 적용 결과는 차이를 보여주고 있으며, 모델링의 결과가 실제보다 낮은 것으로 나타나고 있다.

• 한국식품영양학회지
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• 제33권3호
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• pp.347-355
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• 2020

Cognitive impairment is considered to be key research topics in the field of neurodegenerative diseases and in understanding of learning and memory. In the present study, we investigated neuroprotective effects of Schisandra chinensis (SC) and Ribes fasciculatum (RF) extracts in hydrogen peroxide-induced neuronal cell death in vitro and scopolamine-induced cognitive impairment in Sprague Dawley^® (SD) rat in vivo. Apoptotic cell death in neuroblastic PC12 cell line was induced by hydrogen peroxide for 1 hour at 100 μM. However, mixture of SC and RF treatment prevented peroxide induced PC12 cell death with no neurotoxic effects. For in vivo experiment, the effect of SC and RF extracts on scopolamine-induced cognitive impairment in SD rat was evaluated by spontaneous alternation behavior in Y-Maze test. After 30 min scopolamine injection, the scopolamine-induced rats presented significantly decreased % spontaneous alteration and acetylcholine level, compared to non-induced group. However, treatment of SC+RF extracts rescued the reduced % spontaneous alteration with acetylcholine concentration from hippocampus in scopolamine-induced rats. These results suggested that mixture of SC and RF extract may be a potential natural therapeutic agent for the prevention of cognitive impairment.

• 대한방사선기술학회지:방사선기술과학
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• 제43권5호
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• pp.323-329
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• 2020

The purpose of this study is to investigate the effect of radiation shielding on the thyroid organ dose and image quality during Chest PA examination using automatic exposure control system. This study was conducted in the patient posture and examination conditions such as Chest PA using human model phantom. An experiment without shielding was set as a control group (non) and the cases of using paper coated with a contrast agent (contrast) and bismuth (bismuth) were used as experimental groups. Compared to non-shielded(non), the dose at bismuth increased about 7% in C(cervical vertebrae)5 and C6 and 14% in C7 and contrast showed dose increases of about 17 to 19% in C5 and C6 and about 21% in C7. As a result of the image quality comparison, when measured in the center of the cervical vertebrae, both SNR and CNR in bismuth increased about 40% higher than non, and contrast showed about 8 to 9% improvement. Compared with soft tissues of the cervix, bismuth reduced SNR by about 15% and CNR by about 13%, in contrast, SNR decreased by 11%, and CNR decreased by about 10%. In the Chest PA using AEC, the method of using the shield in front of the collimator has the advantage to observe the anatomical structure of the neck area well compared to the method using the lead. However, the dose at the neck can be increased by 7-21% depending on shielding materials.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2006년도 추계학술대회
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• pp.55-64
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• 2006

The fetal central nervous system (CNS) is sensitive to diverse environmental factors, such as alcohol, heavy metals, irradiation, mycotoxins, neurotransmitters, and DNA damage, because a large number of processes occur during an extended period of development. Fetal neural damage is an important issue affecting the completion of normal CNS development. As many concepts about the brain development have been recently revealed, it is necessary to compare the mechanism of developmental abnormalities induced by extrinsic factors with the normal brain development. To clarify the mechanism of fetal CNS damage, we used one experimental model in which 5-azacytidine (5AZC), a DNA damaging and demethylating agent, was injected to the dams of rodents to damage the fetal brain. 5AzC induced cell death (apoptosis)and cell cycle arrest in the fetal brain, and it lead to microencephaly in the neonatal brain. We investigated the mechanism of apoptosis and cell cycle arrest in the neural progenitor cells in detail, and demonstrated that various cell cycle regulators were changed in response to DNA damage. p53, the guardian of genome, played a main role in these processes. Further, using DNA microarray analysis, tile signal cascades of cell cycle regulation were clearly shown. Our results indicate that neural progenitor cells have the potential to repair the DNA damages via cell cyclearrest and to exclude highly affected cells through the apoptotic process. If the stimulus and subsequent DNA damage are high, brain development proceeds abnormally and results in malformation in the neonatal brain. Although the mechanisms of fetal brain injury and features of brain malformation afterbirth have been well studied, the process between those stages is largely unknown. We hypothesized that the fetal CNS has the ability to repair itself post-injuring, and investigated the repair process after 5AZC-induced damage. Wefound that the damages were repaired by 60 h after the treatment and developmental processes continued. During the repair process, amoeboid microglial cells infiltrated in the brain tissue, some of which ingested apoptotic cells. The expressions of genes categorized to glial cells, inflammation, extracellular matrix, glycolysis, and neurogenesis were upregulated in the DNA microarray analysis. We show here that the developing brain has a capacity to repair the damage induced by the extrinsic stresses, including changing the expression of numerous genes and the induction of microglia to aid the repair process.