• 항공우주기술
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• 제12권2호
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• pp.193-201
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• 2013

프로펠러는 인간동력 항공기 추진시스템의 중요한 구성품이다. 높은 프로펠러 효율을 얻기 위하여 프로펠러는 큰 지름을 가지고 느리게 구동된다. 프로펠러는 인간동력 항공기용 프로펠러 설계 프로그램을 사용하여 설계되었다. 프로펠러의 피치는 지상에서 조정이 가능하다. 본 논문에서는 여러 가지 변수에 대하여 설계에 사용된 동일한 프로그램을 통하여 프로펠러의 성능 해석을 수행하였다. 또한, 파일롯의 체력이나 비행속도의 변화에 따른 탈 설계점 해석도 수행하였다. 설계된 프로펠러는 카본 복합재의 초경량 구조로 제작되어 총 950g의 무게로 제작되었다. 제작된 프로펠러는 아이언 버드에서의 지상 성능 시험을 통하여 속도 및 동력을 측정하고 튜닝을 수행하여 실기에 장착되어 최종적으로 291 m 비행에 성공하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제14권4호
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• pp.213-221
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• 2010

The hypothalamic-pituitary-adrenal (HPA) axis is the primary endocrine system to respond to stress. The HPA axis may be affected by increased level of corticotrophin-releasing factors under chronic stress and by chronic administration of monosodium glutamate (MSG). The purpose of this study was to investigate whether chronic MSG administration aggravates chronic variable stress (CVS)-induced behavioral and hormonal changes. Twenty-four adult male Sprague-Dawley rats, weighing 200~220 g, were divided into 4 groups as follows: water administration (CON), MSG (3 g/kg) administration (MSG), CVS, and CVS with MSG (3 g/kg) administration (CVS＋MSG). In addition, for the purpose of comparing the effect on plasma corticosterone levels between chronic stress and daily care or acute stress, 2 groups were added at the end of the experiment; the 2 new groups were as follows: naive mice (n=7) and mice exposed to restraint stress for 2 h just before decapitation (A-Str, n=7). In an open field test performed after the experiment, the CVS＋MSG group significant decrease in activity. The increase in relative adrenal weights in the CVS and CVS＋MSG group was significantly greater than those in the CON and/or MSG groups. In spite of the increase in the relative adrenal weight, there was a significant decrease in the plasma corticosterone levels in the CVS＋MSG group as compared to all other groups, except the naive group. These results suggest that impaired HPA axis function as well as the decrease in the behavioral activity in adult rats can be induced by chronic MSG administration under CVS rather than CVS alone.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제28권1호
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• pp.4-13
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• 2017

The seeds of addiction are typically sown years prior to the onset of addictive substance use or engagement in addictive behaviors, due to the priming of the reward pathway (RewP) by alterations in the mechanism of stress-signaling from the hypothalamic-pituitary-adrenal axis (HPA) and related pathways. Excessive stress from a single-event and/or cumulative life experiences during childhood, such as those documented in the Adverse Childhood Experiences Study, is translated into neurobiological toxicity that alters the set-point of the HPA axis and limbic system homeostasis [suggested new term: regulation pathway (RegP)]. The resultant alteration of the RegP not only increases the risk for psychiatric and physical illness, but also that for early onset and chronic addictions by dysregulating the RewP. This paper reviews the interface of these symbiotic pathways that result in the phenotypic pathology of emotional dysregulation, cognitive impairment, and compulsive behaviors, as well as morbidity and shorter life expectancy when dysregulated by chronic stress.

• 대한한의학방제학회지
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• 제18권1호
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• pp.133-144
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• 2010

Object : The effects of Rehmanniae Radix(RR) on HPA Axis system and Catecholaminergic system was investigated. Methods : we performed the Forced Swimming Test(FST). Also the expression of Corticotropin -Releasing Factor(CRF), c-Fos and Tyrosine Hydorxylase(TH) was measured by immunohistochemical method at Paraventricular Nucleus(PVN), Locus Coeruleus(LC) and Ventral Tegmental Area(VTA). Results : 1. The duration of immobility in the Forced Swimming Test was significantly decreased in the Rehmanniae Radix 400 mg/kg groups in comparison with the control group(p<0.05). 2. Comparing to the control group, CRF expression was significantly decreased in the Rehmanniae Radix 400 mg/kg treated group in comparison with the control group(p<0.01). 3. c-Fos expression was significantly decreased at PVN in the Rehmanniae Radix 100 mg/kg treated group in comparison with the control group(p<0.01). 4. TH expression was significantly increased at LC in the Rehmanniae Radix 100 mg/kg and 400 mg/kg treated group in comparison with the control group(p<0.001). 5. TH expression was significantly decreased at VTA in the Rehmanniae Radix 100 mg/kg and 400 mg/kg treated group in comparison with the control group(p<0.001). Conclusion : According to the results, it can be considered that Rehmanniae Radix has antidepressant effect by showing the reduction of immobility in FST through the decreased expression of CRF, c-Fos in PVN and TH in VTA.

• 생물정신의학
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• 제17권2호
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• pp.86-93
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• 2010

Objectives : The aim of this research is to determine the effects of depression and anxiety symptoms of schizophrenic psychopathology on the HPA axis. Methods : Twenty patients with schizophrenia were included and divided into the medication non-exposed group(n = 10) and the medication exposed group(n = 10). Evaluated scales were the Positive and Negative Syndrome Scale(PANSS), Scale for the Assessment of Negative Symptoms(SANS), Scale for the Assessment of Positive Symptoms(SAPS), Hamilton Depression Inventory(HAM-D) and Hamilton Anxiety Inventory (HAM-A), and then the combined Dexamethasone/Corticotropin Releasing Hormone(DEX/CRH) test was conducted to determine the basal level, the peak level and the area under the curve(AUC) of cortisol and adrenocorticotropic hormone(ACTH). Results : When the correlations between each psychopathology and cortisol level or ACTH AUC value were analyzed, HAM-D showed a negative correlation, whereas HAM-A showed a positive correlation. Also, the non-depression group(HAM-D ${\leq}$ 18) showed higher cortisol and ACTH concentrations than the depression group(HAM-D > 18), and the anxiety group(HAM-A ${\geq}$ 14) showed significantly higher concentrations than the non-anxiety group(HAM-D < 14)(p < 0.05). Also, as for the comparison between the medication non-exposed group and the medication exposed group, the non-exposed group showed significantly higher cortisol and ACTH concentration than exposed group(p < 0.05). Conclusion : This study suggest that anxiety symptoms rather than depression symptoms are related to the increased activity of the HPA axis of schizophrenics.

• 대한본초학회지
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• 제25권2호
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• pp.117-128
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• 2010

Objectives : In this study the antidepressant effects of mixture of Citri Peticulatae Viride Pericarpium and Lycii Radicis Cortex on the change of HPA-Axis and Catecholamic system was investigated Methods : The forced swimming test(FST) was performed. The expression of corticotropin-releasing factor(CRF), c-Fos in the paraventricular nucleus(PVN), and tyrosine hydroxylase(TH) in the ventral tegmental area(VTA) and locus coeruleus(LC) was measured with immunohistochemical method and the concentration of seum adrenocorticotropic hormone(ACTH) was measured with ELISA method. And the experimental groups were divided into the extraction after mixing(A) and mixture after extraction(B). The effects of both group were compared. Results : The duration of immobility in the forced swimming test was significantly decreased in the A400 group(P<0.01). The expression of CRF in PVN were significantly reduced in the A100, A400, B100, B400groups(P<0.001). but the expression of c-fos in PVN weren't reduced in all groups. And the concentration of ACTH in Plasma were significantly reduced in the A 100 group(P<0.01). The expression of TH in LC were significantly reduced in the A 400, B 100 and B400 groups(P<0.05~P<0.01). Conclusion : Mixture of Citri Peticulatae Viride Pericarpium and Lycii Radicis Cortex has antidepressant effects. But the difference between mixing and extracting methods was not shown.

• The Korean Journal of Physiology and Pharmacology
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• 제27권1호
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• pp.113-125
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• 2023

It has been reported that stressful events in early life influence behavior in adulthood and are associated with different psychiatric disorders, such as major depression, post-traumatic stress disorder, bipolar disorder, and anxiety disorder. Maternal separation (MS) is a representative animal model for reproducing childhood stress. It is used as an animal model for depression, and has well-known effects, such as increasing anxiety behavior and causing abnormalities in the hypothalamic-pituitary-adrenal (HPA) axis. This study investigated the effect of MS on anxiety or aggression-like behavior and the number of GABAergic neurons in the hippocampus. Mice were separated from their dams for four hours per day for 19 d from postnatal day two. Elevated plus maze (EPM) test, resident-intruder (RI) test, and counted glutamic acid decarboxylase 67 (GAD67) or parvalbumin (PV) positive cells in the hippocampus were executed using immunohistochemistry. The maternal segregation group exhibited increased anxiety and aggression in the EPM test and the RI test. GAD67-positive neurons were increased in the hippocampal regions we observed: dentate gyrus (DG), CA3, CA1, subiculum, presubiculum, and parasubiculum. PV-positive neurons were increased in the DG, CA3, presubiculum, and parasubiculum. Consistent with behavioral changes, corticosterone was increased in the MS group, suggesting that the behavioral changes induced by MS were expressed through the effect on the HPA axis. Altogether, MS alters anxiety and aggression levels, possibly through alteration of cytoarchitecture and output of the ventral hippocampus that induces the dysfunction of the HPA axis.

• Perspectives in Nursing Science
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• 제2권1호
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• pp.37-47
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• 2005

Biobehavioral nursing research is focused on generating knowledge that examines relations among biological, behavioral, and social dimensions of health to improve outcomes. In this paper we review the findings of a biobehavioral nursing study of individuals with fibromyalgia (FM) that was framed from the perspective of an individual human response model, the FM literature, and our previous studies in midlife women. We were particularly interested in the studying the role of 'arousal' secondary to pain or to dysregulated hypothalamic-pituitary-adrenal (HPA) axis hormones during sleep and the impact on symptom expression. Unexpectedly, we did not find evidence of, arousal' or abnormal amounts of HPA axis hormones but we did find reduced amounts of growth hormone (GH) and prolactin (PRL) and of sleep spindle activity, a biomarker of sleep maintenance. We discuss these new findings and how our thinking was re-shaped to better understand the role that disturbed sleep plays in symptom expression in FM. It is argued that disturbed sleep maintenance mechanisms coupled with dysregulated somatotrophic-growth hormone axis and sleep-related PRL render individuals vulnerable to the development of or exacerbations of FM symptoms.

• Tuberculosis and Respiratory Diseases
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• 제52권5호
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• pp.529-538
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• 2002

배 경 : 급성 천식발작 치료의 근간을 이루는 전신성 스테이로드는 골다공증, 쿠싱증후군, 당뇨, 고혈압, 출혈성 경향 등의 합병증으로 초기에 흡입용 스테로이드 사용이 추천되고 있다. 흡입성 스테로이드에는 정량분무식 에어로졸(MDI)나 분말형 흡입제(DPI), 무화에어로솔(nebulized aerosol)를 사용해오고 있는데 소아나 노인, 호흡곤란이 아주 심한 성인 환자에서는 무화 에어로졸(nebulized aerosol)을 이용한 budesonide흡입이 효과적일 수 있다. 이에 급성 발작으로 내원한 성인 천식 환자에 nebulized budesonide를 적용했을 때의 임상적인 효과와 스테로이드 보존 효과, 스테로이드의 부작용 중 하나인 시상하부-뇌하수체-부신 축의 이상에 대한 영향을 알고자 하였다. 방 법 : 1. 2000년 6월부터 2001년 9월까지 입원한 기관지 천식, 천식을 동반한 만성 폐질환 환자를 선택하여 1군은 전신성 스테로이드와 nebulized budesonide 2mg을 사용한 군, 2군은 전신성 스테로이드와 budesonide turbuhaler를 사용한 군, 3군은 단지 전신성 스테로이드만을 사용한 군으로 나누고서 최대호기유속, 대기중 동맥혈가스검사, 폐기능검사, 증상지수(호흡곤란, 기침, 야간천식, 천명음), 스테로이드 총량, 입원기간를 기록하여 분석하였다. 2. 내원 10일전부터 어떤 종류의 스테로이드도 쓰지 않았던 환자를 선택하여 budesonide turbuhaler와 nebulized budesonide를 사용한 군으로 나누어 24시간 소변내 코타솔 수치를 측정하여 비교하였다. 결 과 : 1. 임상효과: 순수한 천식환자에서 증상 지수(호흡곤란, 천명음, 기침, 야간천식), 스테로이드 용량, 재원일수, 폐기능 소견, 최대호기유속, 동맥혈가스검사에서 세군간의 차이가 없었고, 천식을 동반한 만성 폐쇄성 폐질환환자를 대상으로 비교했을 때도 세균간의 차이는 없었다. 2. 시상하부-뇌하수체-부진 축의 효과 : nebulizer budesonide 사용군은 turbuhaler 사용군과 마찬가지로 부신축의 억제효과가 있으나 두 군간에 차이는 없었다.(p=0.288) 결 론 : 성인 천식환자에서 급성 발작시 budesonide 형태에 관련없이 전신성 스테로이드만이 치료에 도움을 줄 수 있다는 사실을 확인하였고, 치료 용량의 nebulizer 사용군에서 turbuhaler 사용군과 마찬가지로 시상하부-뇌하수체-부신 축에 대한 억제작용이 있었다.

• Archives of Pharmacal Research
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• 제27권8호
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• pp.863-866
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• 2004

The effect of substance P (Sub P) injected intrathecally (I.t.) on c-fos mRNA expression in vari-ous tissues was examined in the present study. We found that a single administration of Sub P(0.5 nM) caused an increase of the c-fos mRNA level in the hypothalamic-pituitary-adrenal(HPA) axis, hippocampus, and spinal cord. The time-course study showed that c-fos mRNA level was maximal at 10 min and began to decrease 30 min after the Sub P injection in all tis-sues, and the Sub P-induced increase of the c-fos mRNA level was returned to the control level 1 h after the injection. The kinetics of the c-fos mRNA expression in mice that were repeatedly injected with Sub P (every 30 min interval up to 4 times) were different in the HPA axis, hippocampus, and spinal cord. The increased c-fos mRNA level in the hypothalamus and the spinal cord induced by I.t. injected Sub P remained at a high level. In the pituitary gland, adrenal gland, and hippocampus, the increased level of c-fos mRNA expression gradually returned to the control level during the repeated substance P injections up to 4 times. Our results suggest that spinally injected Sub P-induced pain stress increases c-fos mRNA expres-sion in the spinal cord, hippocampus, and HPA axis. In mice repeatedly injected with Sub P, the kinetics of c-fos mRNA appear to be different varied from tissue to tissue.