• 약학회지
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• 제38권2호
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• pp.149-157
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• 1994

The role of nitric oxide(NO) as neurotransmitter in non-adrenergic non-cholinergic (NANC) relaxation induced by electrical stimulation has been studied in circular muscle strips of the rabbit gastric fundus. In the presence of atropine and guanethidine, low frequency$(1{\sim}20\;Hz)$ and short trains (5s) of electrical stimulation induced the frequency-dependent relaxations which were not affected by adrenergic and cholinergic blockage, but abolished by tetrodotoxin, a nerve conductance blocker. L-NNA, a stereospecific inhibitor of NO biosynthesis, inhibited the relaxations induced by electrical stimulation but not affected the relaxation to exogenous NO. The effect of L-NNA was prevented by L-arginine, the precursor of the NO biosynthesis, but not by its enantiomer, D-arginine. Exogenous administration of NO$(10{\sim}100\;{\mu}M)$ caused the concentration-dependent relaxation which showed a similarity to those obtained with electrical stimulation. Hemoglobin, a NO scavenger, abolished the NO-induced relaxations and also markedly inhibited those evoked by electrical stimulation. Application of adenosine triphosphate$(1{\sim}10\;{\mu}M)$ induced concentration-independent contractions, but in high dose caused temporary contraction followed by relaxation which was not affected by L-NNA. Exogenous vasoactive intestinal polypeptide$(10{\sim}100\;nM)$ induced the concentration-dependent relaxation, while its effects were slower in onset and more persistent than those induced by short trains and low frequencies of electrical stimulation. Based on above results, it is suggested that NO is the principal neurotransmitter of NANC nerve at relaxation induced by short trains and low frequencies of electrical stimulation in the rabbit gastric fundus.

• Physical Therapy Rehabilitation Science
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• 제5권3호
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• pp.138-142
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• 2016

Objective: The purpose of this study was to investigate how light touch with a finger affects balance ability when a posture is maintained in the condition of visual information blockage and to provide a fundamental material for developing balance ability in the process of rehabilitation treatment. Design: Cross-sectional study. Methods: The study subjects were 17 healthy men and women in their twenties and thirties who were studying at S University in Seoul. The system was comprised of an equilateral triangular force platform. Subjects were asked to step on the foot position of the force platform (Good Balance, Finland) barefooted for 30 seconds, with eyes closed, hands hanging down loosely, and feet comfortably apart. It was connected to a laptop by using Bluetooth technology. An experiment was conducted in the following three circumstances: 1) no-touch trial, 2) light touch to the back (T7 area), and 3) light touch to the middle finger of the left hand. Each subject was given a 10-minute break between consecutive measurements. The experimental circumstances were performed randomly. Anteroposterior sway (APSV), mediolateral sway velocity (MLSV), and velocity moment (VM) were measured. Results: The APSVs (mm/s) were $9.32{\pm}3.37$ and $5.45{\pm}2.98$; the MLSVs (mm/s), $6.39{\pm}3.35$ and $3.31{\pm}2.48$; and VM ($mm^2/s$), $17.13{\pm}11.75$ and $6.76{\pm}8.31$ in the first and second experimental circumstances, respectively. APSV, MLSV, and VM values were significantly improved with the 1) no-touch trial and 2) light touch to the back trail conditions compared with the 3) light touch to the middle finger of the left hand condition (p<0.05). Conclusions: This study revealed that the balance ability for maintaining a body posture was influenced more by light touch to the back (T7) than by light touch with the sensitive fingertip and body sway diminished after visual information was blocked.

• 한국임상약학회지
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• 제21권4호
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• pp.364-375
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• 2011

Given that single blockade with angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) can achieve only partial and undurable suppression of the Renin Angiotensin System (RAS), it has been hypothesized that dual blockage would be more beneficial in the management of blood pressure (BP) reduction and prevention of progressive chronic kidney disease (CKD) than either agent alone. Thus, it has been suggested that the combination of an ACEI and an ARB might provide renal benefits to hypertensive patients over and above BP reduction. However, this might also expose patients to additive or synergistic side effects. We attempted to conduct a systematic review to evaluate the benefits and harms of combination therapy in hypertensive patients with or without kidney diseases. MEDLINE and KoreaMed were searched for relevant randomized clinical trials in adult hypertensive patients with or without diabetes (restricted to 1997, limited to trials published in English). Results were summarized using the random-effects model, and between-studies heterogeneity was estimated with $I^2$. A final analysis of ten trials (23,928 patients) revealed that the combination of an ACEI and an ARB reduced blood pressure (SBP/DBP) by 3.95/2.02 mmHg (95% confidence interval [CI], -4.38 to -3.53/-2.33 to -1.71) compared with ACEI monotherapy, and 2.83/2.64 mmHg (95% CI, -3.25 to -2.41/-4.95 to -0.33) compared with ARB monotherapy. Eight trials (391 patients) demonstrated a significant reduction in 24h-proteinuria (weighted mean difference, 0.16 g/day, 95% CI, -0.26-0.05), but they did not translate into an improvement in GFR. Tests for heterogeneity showed no difference in effect among the studies. The combination therapy reduced proteinuria by 30% (95% CI, 23% to 37%) and 39% (95% CI, 31% to 48%) compared with ACEI monotherapy and ARB monotherapy, respectively. However, in patients who had proteinuria more than 0.5 g/day, the combination therapy failed to show significant reduction in urinary protein excretion. The current cumulative evidence suggests that diabetic patients with proteinuria on dual RAS blockade have an increase risk of adverse events such as hyperkalemia, hypotension, and so on, compared with ACEI or ARB alone. It is, therefore, proposed that the combination therapy should not be routinely used for the treatment of hypertension with or without compelling indications.

• 한국지하수토양환경학회지:지하수토양환경
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• 제8권1호
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• pp.75-80
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• 2003

해수 중에는 연안 조간대의 저서생물의 생존에 필수적인 용존산소와 영양염이 풍부하게 내포되어 있기 때문에 해수의 토양침투는 저서생물의 생존과 밀접한 관련을 맺고 있다. 그러나 유출된 기름이 조간대에 표착하게 되면 해수의 침투가 차단되어 생물에게 많은 피해를 유발시킬 것이다. 또한 유출된 기름의 토양 침투에 관한 정보는 생태계 영향을 최소화하고 처리를 위한 대책수립의 단서로서 매우 중요하다. 본 연구에서는 유출된 기름의 침투 거동을 파악하고 침투된 기름의 해수 침투 차단을 검토하는 것을 목적으로 하여 연구를 수행하였다. 점도가 낮은 원유가 C중유보다 침투 깊이가 약 2배 깊었으며, 유출된 기름의 침투 깊이는 조간대에 표착된 기름의 양에 따라 영향을 받는 것을 알 수 있었다. 그리고 표착된 기름은 첫번째 조석에서 가장 급격한 침투거동을 보였으나, 두번째 조석변동부터는 급격한 침투 변화는 나타나지 않았다. 그리고 침투한 유분의 수직적 분포로부터 기름은 토양 표층 2cm에 집중적으로 분포하는 것을 알 수 있었다. 한편 해수의 침투량은 표착유의 양에 비례적으로 감소하였으며, C중유가 원유보다 약 1.7배 정도의 해수의 토양 침투량을 감소시키는 것을 알 수 있었다. 따라서, 침투한 기름의 처리는 가능한 빠른 시간내에 수행되어야 해수의 침투를 회복시켜 연안 조간대 생태계의 피해를 최소화 시킬 수 있다고 판단된다.

• Experimental and Molecular Medicine
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• 제50권11호
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• pp.13.1-13.15
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• 2018

Wound healing is delayed in diabetic patients. Increased apoptosis and endothelial progenitor cell (EPC) dysfunction are implicated in delayed diabetic wound healing. Melatonin, a major secretory product of the pineal gland, promotes diabetic wound healing; however, its mechanism of action remains unclear. Here, EPCs were isolated from the bone marrow of mice. Treatment of EPCs with melatonin alleviated advanced glycation end product (AGE)-induced apoptosis and cellular dysfunction. We further examined autophagy flux after melatonin treatment and found increased light chain 3 (LC3) and p62 protein levels in AGE-treated EPCs. However, lysosome-associated membrane protein 2 expression was decreased, indicating that autophagy flux was impaired in EPCs treated with AGEs. We then evaluated autophagy flux after melatonin treatment and found that melatonin increased the LC3 levels, but attenuated the accumulation of p62, suggesting a stimulatory effect of melatonin on autophagy flux. Blockage of autophagy flux by chloroquine partially abolished the protective effects of melatonin, indicating that autophagy flux is involved in the protective effects of melatonin. Furthermore, we found that the AMPK/mTOR signaling pathway is involved in autophagy flux stimulation by melatonin. An in vivo study also illustrated that melatonin treatment ameliorated impaired wound healing in a streptozotocin-induced diabetic wound healing model. Thus, our study shows that melatonin protects EPCs against apoptosis and dysfunction via autophagy flux stimulation and ameliorates impaired wound healing in vivo, providing insight into its mechanism of action in diabetic wound healing.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.112-112
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• 2019

Baicalein is one of the main flavonoids derived from roots of Scutellaria baicalensis Georgi, a traditional Oriental medicine. Although baicalein has high antitumor effect on several human carcinomas, the mechanism responsible for this property is not unclear. In this study, the data revealed that baicale-ininduced growth inhibition was associated with the induction of apoptosis connecting with cytochrome c release, down-regulation of anti-apoptotic Bcl-xl and increased the percentage of cells with a loss of mitochondria membrane permeabilization. Baicalein also induced the proteolytic activation of caspases and cleavage of PARP; however, blockage of caspases activation by z-VAD-fmk inhibited baicalein-induced apoptosis. In addition, baicalein enhanced the formation of autophagosomes and up-regulated LC3-II/LC3-I ratio. Interestingly, the pretreatment of bafilomycin A1 recovered baicalein-induced cell death suggesting that autophagy by baicalein roles as protective autophagy. Taken together, our results indicated that this flavonoid induces apoptosis and cell protective autophagy. These data means combination treatment with baicalein and autophagy inhibitor might be a promising anticancer drug.

• 한국연안방재학회지
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• 제5권4호
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• pp.173-182
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• 2018

As the research about increasing the efficiency of dredging soil transport, the technology, which reduce the friction between pipe wall and fluid in the pipe and disturbed generating pipe blockage, has been developed. So for the purpose of applying this technology to real construction site, main test has been tried at the real scale test in field. As a test result, this paper will show 30% flow efficiency increasing by permitted electro magnetic force to the pipe. And test result was evaluated as a ultra sonic velocity profiler. To propose the design technique and the execution manual of the high efficiency dredging material transport technic, this research have confirmed flow status changing depending on a soil material kind under electro-magnetic field and analyze the effect of electro-magnetic field which affects to each dredged soil material transportation. For achieving this research, EMF(Electro-Magnetic Field) generator is installed on the dredger(20,000HP) and through monitored flow status, dredging soil flow rate and sampled material specification is confirmed. Also dredger operating condition is measured and dredger power for soil transportation, hydraulic gradient and flow rate are compared, as transportation efficiency is calculated by this parameter, it is possible to check transportation efficiency improvement depending on each dredged soil material under electro-magnetic field. To verify the technique of dredged soil transfer using electromagnetic field, which is the core technique of the high efficiency dredged soil transfer, and the technique of expert system for pipeline transfer and the flow state. This could lead to a verification of transfer efficiency according to the characteristics of the dredged soil (sand, clay, silt) and the transfer distance (5km, 10km, 15km), which is planned to be used for a technology development of pump power reduction and long-distance transfer applying the high efficiency dredged soil transfer technology.

• 대한본초학회지
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• 제28권4호
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• pp.63-69
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• 2013

Objectives : The purpose of present study was to investigate the vasorelaxant activities and mechanisms of action of the ethanol extract of P. yedoensis leaf (PYL) on isolated rat aortic rings. Methods : Dried P. yedoensis leaves were extracted 3 times with 100% ethanol for 3 h in a reflux apparatus. Isolated rat aortic rings were suspended in organ chambers containing 10 ml Krebs-Henseleit (K-H) solution. The rings were maintained at $37^{\circ}C$ and aerated with a mixture of 95% $O_2$ and 5% $CO_2$. Changes in their tension were recorded via isometric transducers connected to a data acquisition system. Results : PYL relaxed the contraction of aortic rings induced by phenylephrine (PE, 1 ${\mu}M$) or KCl (60 mM) in a concentration dependent manner. However, the vasorelaxant effects of PYL on endothelium-denuded aortic rings were lower than endothelium-intact aortic rings. And the vasorelaxant effects of PYL on endothelium-intact aortic rings were reduced by pre-treatment with $N{\omega}$-Nitro-L-arginine methyl ester (10 ${\mu}M$), methylene blue (10 ${\mu}M$), 1-H-[1,2,4]-oxadiazolo-[4,3-${\alpha}$]-quinoxalin-1-one (10 ${\mu}M$), tetraethylammonium (5 mM). In addition, PYL inhibited the contraction induced by extracellular $Ca^{2+}$ in endothelium-denuded aortic rings pre-contracted by PE or KCl in $Ca^{2+}$-free K-H solution. Conclusions : These results suggest that PYL exerts its vasorelaxant effects via the activation of Nitric Oxide (NO) formation by means of L-arginine and NO-cGMP pathways and via the blockage of receptor operated calcium channels, voltage dependent calcium channels and calcium-activated potassium channels.

• 한국지반환경공학회 논문집
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• 제23권9호
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• pp.5-16
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• 2022

최근 도시 및 지하공간 개발에 따라 지반재해가 증가하고, 사회문제로도 이어지고 있다. 이러한 문제를 해결하기 위해 일반적으로 그라우팅 공법이 사용되나, 낮은 침투성, 겔화특성 등의 재료적 한계와 인장저항력 부족 문제를 가지고 있어 지반의 역학적 성능을 개선하지 못하고 있다. 따라서 최근에는 섬유를 혼합한 그라우트재 연구 등 역학적 성능 개선을 위한 연구가 진행되고 있다. 그러나 일반적인 섬유는 교반 및 주입 시 주입구 막힘, 주입관 폐색 등의 문제를 유발해 실제 지반 주입에 많은 어려움을 가지고 있다. 이에 본 연구에서는 그라우트 인장보강재로 실제 주입이 가능한 CNT Powder를 사용해 'CNT-mixed grout재'를 고안하고, 역학적 거동 분석과 주입 가능성, 구근 특성, 적용성 분석을 수행하였다. 역학적 성능 시험결과 CNT Powder의 최적 함유량은 0.5 %로 확인되었고, 1차원 주입시험과 모형 구근 형성시험을 통해 적정 주입인자와 구근의 특성을 파악하였다. 수치해석을 통한 적용성 분석을 수행하여 CNT-Mixed grout재가 침하량과 소성영역 감소 등의 효과를 나타내어 지반에 주입 가능한 인장보강재로서 활용이 가능함을 확인하였다.

• 현장농수산연구지
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• 제7권1호
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• pp.35-46
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• 2005

규산질비료이용 복토직파재배 개선을 위한 폿트시험 연구에서 얻어진 결과를 요약하면 다음과 같다. 본 연구에서 복토재료에 따른 초기 입모율차이는 무복토 55.0%에 비하여 복토처리로 90~100%의 높은 입모율을 보였다. 특히 파종직후 강우조건에서는 무복토 0%의 출아를 보인반면 복토처리에서는 65~100%의 입모율을 보였으며 강우 시에는 무복토 조건에서도 85%의 비교적 높은 입모율을 보였다. 특히 토양을 이용한 복토처리구에서는 강우로 인하여 20%의 매우 낮은 입모율을 보였는데 이는 수분에 의한 토양층 형성으로 산소공급 및 유모출아 조건이 불량하여 입모율이 극히 저조한 것으로 나타났다. 출수기 벼 생육은 무복토(비강우)처리구를 제외한 모든 처리구에서 비교적 양호한 벼 생육을 보였다. 벼 수량은 초기 입모 및 중간생육이 불량한 무복토(비강우) 및 토양 복토구(강우)에서 낮은 수량성을 각각 보였다.