• YAKHAK HOEJI
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• v.38 no.2
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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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• v.5 no.3
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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.

• Korean Journal of Clinical Pharmacy
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• v.21 no.4
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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.

• Journal of Soil and Groundwater Environment
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• v.8 no.1
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• pp.75-80
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• 2003

Understanding the seawater infiltration into tidal flat sediments is very important, because it is significantly correlated with the supply of dissolved oxygen, nutrients and organic matter to benthic organisms for survival. However oil blocks interstitial spaces of sediments, reduces seawater infiltration and results in the decrease in oxygen, nutrients and other food supply to benthic communities. The penetration depth of the stranded oil into the sediments is one of the most significant information to know the effect of spilled oil on biological communities and to set up a cleaning method. So we initiated this study to quantify the penetration behavior of spilled oil and to evaluate the influence of the penetrated oil on seawater infiltration in tidal flat environment and its ecological implications. The penetration depth of the crude oil into the tidal flat sediments was two times deeper than that of the fuel oil C, and the depth was significantly affected by stranded oil volume. However, the penetration depth of stranded oil was abruptly dropped at first falling tide but not significantly fluctuated after that. Moreover, hydrocarbon concentration showed the highest within the upper 2 cm. Seawater infiltration was decreased in proportion to the stranded oil volume. The seawater infiltration was more affected by the penetrated fuel oil C about 1.7 times than the crude oil, because the interstitial spaces of the top of sediments were more cleared by the fuel oil C. Therefore, quick cleaning actions for penetrated oil will be necessary for recovery of seawater infiltration because the seawater contains oxygen and nutrients necessary for the survival of benthic organisms in tidal flat.

• Experimental and Molecular Medicine
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• v.50 no.11
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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.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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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.

• Journal of Coastal Disaster Prevention
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• v.5 no.4
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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.

• The Korea Journal of Herbology
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• v.28 no.4
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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.

• Journal of the Korean GEO-environmental Society
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• v.23 no.9
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• pp.5-16
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• 2022

In recent years due to the development of urban and underground space, the number of ground disasters is increasing, and it is also leading to social problems. To solve the problem, a grouting method is generally used. However, the grouting method has material (grout) limitations in permeability, gelation properties and tensile resistance. Therefore, research on grout materials mixed with fibers is actively carried out to improve the problems. However, in the actual ground injection process, many difficulties have been faced causing the blockage of the inlet port and the injection tube. In this study, 'CNT-mixed grout material' was developed using CNT powder that can reinforce the tensile strength of soils. The uniaxial compressive and tensile strength tests were performed to obtain the optimal content and mechanical properties of the CNT Powder-mixed grout. It was found that the optimal CNT powder content is 0.5% that gives the average maximum strength. A one-dimensional injection test and the bulb formation test were carried out, and it was identified that the injection rate and bulb form could be controlled by pressure and mixing ratio. Field application of the CNT-Mixed grout is simulated using numerical analysis of slopes, foundations, and tunnels reinforced in several types. The positive effect of reducing plastic ranges and settlements was confirmed.

• Journal of Practical Agriculture & Fisheries Research
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• v.7 no.1
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• pp.35-46
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• 2005

This research was conducted to improve and establish Bokto direct seeding technology use of silicate in rice. Bokto direct seeding technology has recently released to alternative new method for transplanting method of the rice plant. In recent rice production has serious problem due to higher cost and labor shortage in Korea. In particular rice has been faced on open market to internationally due to WTO, FTA agreement etc. Thus rice growers in Korea have been more concentrated on cost reduction using by direct seeding technology such as dry seeding and water seeding while those methods have severe constraints like poor seedling, more weed occurrence, lodging and poor grain quality. In recent a new technology for improvement of these problem has released to farmer's field and proven to alternative rice growing technology of transplanting. In this technology there was additional application of silicate which has known as soil improvement and this research was obtained in the following results. At the application of silicate, sand, and soil there was high in seedling establishment by 90~100% in pot experiment but there was 55.0% seedling stand of the untreated control. Under dry condition seedling stand was 0% at the untreated control while 65~100% high in application of silicate, sand, and soil. Meanwhile, under rainy condition untreated control there was 85% of seedling stand but soil application was 20% of seedling establishment due to blocking of oxygen and physical soil blockage.