• Biomolecules & Therapeutics
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• 제17권1호
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• pp.32-42
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• 2009

The purpose of the present study was to examine the effect of dihydrexidine, a full $D_1$ receptor agonist, on the secretion of catecholamines (CA) from the perfused model of the rat adrenal gland, and to establish its mechanism of action. Dihydrexidine (10-100 ${\mu}M$), perfused into an adrenal vein for 60 min, relatively produced dose- and time-dependent inhibition in the CA secretory responses evoked by ACh (5.32 mM), high $K^+$ (56 mM), DMPP (100 ${\mu}M$) and McN-A-343 (100 ${\mu}M$). Dihydrexidine itself did fail to affect basal CA output. Also, in adrenal glands loaded with dihydrexidine (30 ${\mu}M$), the CA secretory responses evoked by Bay-K-8644 (10 ${\mu}M$), an activator of L-type $Ca^{2+}$ channels, cyclopiazonic acid (10 ${\mu}M$), an inhibitor of cytoplasmic $Ca^{2+}$-ATPase, and veratridine, an activator of voltage-dependent $Na+$ channels (10 ${\mu}M$), were also markedly inhibited, respectively. However, in the simultaneous presence of dihydrexidine (30 ${\mu}M$) and R (+)-SCH23390 (a selective antagonist of $D_1$ receptor, 3 ${\mu}M$), the CA secretory responses evoked by ACh, high K+, DMPP, McN-A-343, Bay-K-8644, cyclopiazonic acid and veratridine were considerably recovered to the extent of the corresponding control secretion compared with the inhibitory responses by dihydrexidinetreatment alone. In conclusion, these experimental results suggest that dihydrexidine significantly inhibits the CA secretion evoked by cholinergic stimulation (both nicotinic and muscarinic receptors) and membrane depolarization from the rat adrenal medulla. It seems that this inhibitory effect of dihydrexidine may be mediated by inhibiting influx of both $Ca^{2+}$ and $Na^+$ into the cytoplasm as well as by suppression of $Ca^{2+}$ release from cytoplasmic calcium store through activation of dopaminergic $D_1$ receptors located on the rat adrenomedullary chromaffin cells.

• 한국임상수의학회지
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• 제27권4호
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• pp.453-456
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• 2010

생후 1개월령의 0.9 kg수컷 삽살개가 식욕부진, 배뇨곤란, 기립곤란, 침울을 주증으로 병원에 내원하였다. 신체검사에서는 빈맥, 저체온증, 점막창백 소견을 보였다. 혈액검사에서는 백혈구증가증과 빈혈소견이 있었고, 혈청생화학검사에서는 BUN (57.3 mg/dl)과 $NH_3$ ($584\;{\mu}g/dl$)의 증가, 알부민과 나트륨 및 칼륨의 저하소견을 보였다. 뇨검사에서는 혈뇨, 단백뇨, 당뇨, 세균뇨(Staphylococcus spp.)와 인산암모늄마그네슘결정뇨의 소견을 보였다. 방사선 검사에서는 확장된 방광과 요도내 2 mm크기의 결석을 발견할 수 있었다. 요도절개술로 요도내 결석을 제거하였고, 수술 후 환자는 정상적으로 회복되었다. 본 케이스는 요소분해효소 생산 세균의 감염과 고암모니아증을 동반한 어린 삽살개에서 스트루바이트 결석증 발생하였음을 보고한다.

• 대한수의학회지
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• 제45권4호
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• pp.593-599
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• 2005

An abattoir study on the abdominal fat necrosis in adult cattle was performed pathologically. Grossly, masses of fat necrosis were leekgreen in colour, lobulated on the cut surface, and saponificated in the texture. These necrotic adipose tissues infiltrated usually into neighboring parenchymal organs including intestines and pancreas, leading to fibrosis or atrophy of them. Histopathologically, necrotic fat cells contained acidophilic, opaque, amorphous substance or basophilic fibrillar or granular minerals in their cytoplasms. The lesions of fat necrosis were divided by fibroconnective tissue. With increase of the severity, necrotic fat cells fused each other and then formed fat cysts. In this severe lesion, necrotic fat cells were partialy or completely replaced by macrophages. Multinucleated giant cells were scattered in this lesion. Interestingly, small artery in the lesion of fat necrosis revealed severe thickening of internal elastic membrane. Severe fibrosis was observed in or between the outer longitudinal and inner circular muscular externas causing segregation, degeneration and necrosis of muscle fibers. The nerve cells of Auerbach's and Meissner's plexuses surrounded by fibrosis were degenerated or necrotic. In addition, necrotic fat cells infiltrated into the pancreas, resulting in pancreas atrophy. From these results, it is speculated that fat necrosis might compromise intestinal movement due to necrosis of muscular externa and ganglion cells of Auerbach's and Meissner's plexuses.

• 한국물환경학회지
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• 제36권1호
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• pp.55-68
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• 2020

Because of the intensified environmental problems such as climate change and resource depletion, sewage treatment technology focused on energy management has recently attracted attention. The conversion of primary sludge from the primary sedimentation tank and excessive sludge from the secondary sedimentation tank into biogas is the key to energy-positive sewage treatment. In particular, the primary sedimentation tanks recover enriched biodegradable organic matter and anaerobic digestion process produces methane from the organic wastes for energy production. Such technologies for minimizing oxygen demand are leading the innovation regarding sewage treatment plants. However, sewage treatment facilities in Korea lack core technology and operational know-how. Actually, the energy potential of sewage is higher than sewage treatment energy consumption in the sewage treatment, but current processes are not adequately efficient in energy recovery. To improve this, it is possible to apply chemically enhanced primary treatment (CEPT), high-rate activated sludge (HRAS), and anaerobic membrane bioreactor (AnMBR) to the primary sedimentation tank. To maximize the methane production of sewage treatment plants, organic wastes such as food waste and livestock manure can be digested. Additionally, mechanical pretreatment, thermal hydrolysis, and chemical pretreatment would enhance the methane conversion of organic waste. Power generation systems based on internal combustion engines are susceptible to heat source losses, requiring breakthrough energy conversion systems such as fuel cells. To realize the energy positive sewage treatment plant, primary organic matter recovery from sewage, biogas pretreatment, and co-digestion should be optimized in the energy management system based on the knowledge-based operation.

• Molecules and Cells
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• 제27권3호
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• pp.307-312
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• 2009

The interstitial cells of Cajal (ICC) are pacemaking cells required for gastrointestinal motility. The possibility of whether DA-9701, a novel prokinetic agent formulated with Pharbitis Semen and Corydalis Tuber, modulates pacemaker activities in the ICC was tested using the whole cell patch clamp technique. DA-9701 produced membrane depolarization and increased tonic inward pacemaker currents in the voltage-clamp mode. The application of flufenamic acid, a non-selective cation channel blocker, but not niflumic acid, abolished the generation of pacemaker currents induced by DA-9701. Pretreatment with a $Ca^{2+}$-free solution and thapsigargin, a $Ca^{2+}$-ATPase inhibitor in the endoplasmic reticulum, abolished the generation of pacemaker currents. In addition, the tonic inward currents were inhibited by U-73122, an active phospholipase C inhibitor, but not by $GDP-{\beta}-S$, which permanently binds G-binding proteins. Furthermore, the protein kinase C inhibitors, chelerythrine and calphostin C, did not block the DA-9701-induced pacemaker currents. These results suggest that DA-9701 might affect gastrointestinal motility by the modulation of pacemaker activity in the ICC, and the activation is associated with the non-selective cationic channels via external $Ca^{2+}$ influx, phospholipase C activation, and $Ca^{2+}$ release from internal storage in a G protein-independent and protein kinase C-independent manner.

• 한국표면공학회지
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• 제44권5호
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• pp.173-178
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• 2011

Separator of stack in polymer electrolyte membrane fuel cell (PEMFC) is high cost and heavy. If we make it low cost and lighter, it will have a great ripple. In this study, low carbon steel is used as base metal of separator because the cost of low carbon steel is very cheaper commercial metal material than stainless steels, which is widely used as separator. Low carbon steel has not a good corrosion resistance. In order to improve the corrosion resistance and electrolytic conductivity, low carbon steel needs to be surface treated. We made Chromium electroplated layer of $5{\mu}m$, $10{\mu}m$ thickness on the surface of low carbon steel and it was nitrided for 2 hours at $1000^{\circ}C$ in a furnace with 100 torr nitrogen gas pressure. Cross-sectional and surface microstructures of surface treated low carbon steel are investigated using SEM. And crystal structures are investigated by XRD. Interfacial contact resistance and corrosion tests were considered to simulate the internal operating conditions of PEMFC stack. The corrosion test was performed in 0.1 N $H_2SO_4$ + 2 ppm $F^-$ solution at $80^{\circ}C$. Throughout this research, we try to know that low carbon steel can be replaced stainless steel in separator of PEMFC.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.47-47
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• 2003

The presenilin 1 (PS1) or PS2 is an essential component of the ${\gamma}$-secretase complex, which mediates the intramembrane proteolysis of selected type-I membrane, including the ${\beta}$-amyloid precursor protein (APP) to yield A${\beta}$. Familial Alzheimer's disease (FAD)-associated mutations in presenilins give rise to an increased production of a highly amyloidogenic A${\beta}$42. In addition to their well-documented proteolytic function, the presenilins play a role in calcium signaling. We have previously reported that presenilin FAD mutations cause highly consistent alterations in intracellular calcium signaling pathways, which include deficits in capacitative calcium entry (CCE), the refilling mechanism for depleted internal calcium stores. However, molecular basis for the presenilin-mediated modulation of CCE remains to be elucidated. In the present study, whole-cell patch clamp method was used to identify a specific calcium-permeable ion channel current(s) that is responsible for the CCE deficits associated with FAD-linked PS1 mutants. Unexpectedly, both voltage-activated and conventional store depletion-activated calcium currents I(CRAC), were absent in HEK293 cells, which were stably transfected either with wild-type or FAD mutant (L286V, M146L, and delta E9) forms of PS1. Recently, magnesium-nucleotide-regulated metal cation current, or I(MagNum), has been described and appears to share many common properties with I(CRAC) including calcium permeability and inhibitor sensitivity (e.g. 2-APB). We have detected I(MagNum) in all 293 cells tested. Interestingly, FAD mutant 293 cells developed only about half of currents compared to PS1 wild type cells.

• 전기화학회지
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• 제6권3호
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• pp.212-216
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• 2003

고분자전해질형 연료전지에 사용되는 외부 및 내부 가습기를 통과한 반응 기체의 상대습도와 온도를 측정한 자료가 실시간으로 컴퓨터에 입력되어지는 시스템을 자체적으로 구성하였다. 이 시스템을 이용하여 측정한 경우 10-20분이 경과한 후에 습도 값이 안정되었으므로 가습 측정치에 대한 신뢰성을 향상시킬 수 있었으며, 여러 가지 가습의 영향을 해석할 수 있었다. 측정 장비의 이상을 초래할 수 있는 상대 습도가 $100\%$부근의 영역에서 지속적으로 측정을 수행할 경우 센서의 오작동 내지 고장의 원인이 될 수 있었으므로 실험시 주의가 필요하였다. 가습기를 통과한 반응기체는 유량이 증가할수록 가습되는 양은 증가하나, 일정 유량 이상이 되면 그 증가폭이 감소하는 경향을 보였는데 이는 가습기 출 통과하는 기체의 체류 시간 영향에 기인한 것으로 추정되어진다.

• 동국한의학연구소논문집
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• 제8권1호
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• pp.117-131
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• 1999

Yangkyuksanhoa-tang is frequently used for cerebrovascular accident(CVA). The present study was performed to investigate the effect of Yangkyuksanhoa-tang on the peri vascular immunoreactive nerve fiber of the basilar artery after experimentally induced subarachnoid hemorrhage(SAH). Sprague Dawley rats weighing between 350-400g were used. The SAH induced by injection of the fresh autologus heart blood(0.3-0.4ml) into the cisterna magna through the posterior atlanto-occipital membrane. Sample group was given a $3.3m{\ell}/kg/day$ of Yangkyuksanhoa-tang extracts for 2 days after SAH. The experimental animals divided into 48hrs after SAH. The changes of perivascular immunoreactive nerve fiber was examined by using indirect immunofluorescence method. The meshlike perivascular nerve fiber appeared in the basilar artery of normal rats. In basilar artery of SAH elicitated rat, the distribution of calcitonin gene-related peptide (CGRP)-immunoreactivity(IR) and vasoactive intestinal polypeptide(VIP)-IR of the perivascular nerve fiber were remarkably diminished, also dopamine beta hydroxylase(DBH)-IR, neuropeptide Y(NPY)-IR and serotonin-IR were diminished. In SAH elicitated rat with Yangkyuksanhoa-tang treatment, the CGRP-IR and VIP-IR degree were repaired as well as normal rat's, but DBH-IR, NPY-IR and serotonin-IR had no changes. These results provide the basic data to investigate the effect of Yangkyuksanhoa-tang on the vasospasm after SAH.

• 혜화의학회지
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• 제19권1호
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• pp.25-34
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• 2010

Background : The human being and the bacteria have accomplished a balance and have coexisted each other during long time. Probiotics have evolved with the human host to exist and the result they have operated profitably to human host. So it requires that the functions of probiotics are expounded in view of Traditional Korean Medicine. Aim : Suggest the functions of probiotics in view of Traditional Korean Medicine. Method : The author's research has been performed to review the related references. Results : Probiotics assist the absorption of the lactose, proteins and minerals and product several kinds of vitamins, organic acids. Probiotics suppresses the growth of noxious bacteria and the production of harmful substances or gases. They absorbed and discharge the bile acid, and thus help us maintain the optimal level of blood cholesterol concentration. They can reinforce the immune response of the mucous membrane and control the hypersensitivity immune reaction such as asthma, atopy on the other hand. Probiotics have right functions as above and so can be applied widely in treatment of various disease and symptom. Conclusion : Considering the functions of probiotics in view of Traditional Korean Medicine, they participate in our spleen-earth-system (digestion and synthesis) and liver-wood-system (regulation of digestion, metabolism, internal secretion etc.), assist the function of lung-metal system(respiration and regulation of water metabolism) and regulate wi-chi (reinforce/control immune system). Consequently, hereafter there would be a necessity of control a circumstance in treatment of various diseases under these categories that probiotics should be able to do their right functions inside the human body.