• The Korean Journal of Physiology and Pharmacology
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• 제4권5호
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• pp.347-353
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• 2000

It has been well documented that a massive release of not only glutamate but also other neurotransmitters may modulate the final responses of nerve cells to the ischemic neuronal injury. But there is no information regarding whether the release of monoamines is directly associated with synaptic vesicular proteins under ischemia. In the present study, it was investigated whether synapsin 1, syntaxin and SNAP-25 are involved in the release of 5-hydroxytryptamine $([^3H]5-HT)$ in glucose/oxygen deprived (GOD) rat hippocampal slices. And, the effect of NMDA receptor using DL-2-amino-5-phosphonovaleric acid (APV) on ischemia- induced release of 5-HT and the changes of the above proteins were also investigated. GOD for 20 minutes enhanced release of $[^3H]5-HT,$ which was in part blocked by the NMDA receptor antagonist, APV. The augmented expression of synapsin 1 during GOD for 20 minutes, which was also in part prevented by APV. In contrast, the expression of syntaxin and SNAP-25 were not altered during GOD. These results suggest that ischemic insult induces release of $[^3H]5-HT$ associated with synapsin 1, synaptic vesicular protein, via activation of NMDA receptor in part.

• Journal of Nutrition and Health
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• 제25권7호
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• pp.597-607
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• 1992

The present study examined effects of caffeine on coronary circulation myocardial oxygen me-tabolism and calcium release in isolated perfused guinea pig hearts. Intracoronary caffeine({{{{ {10 }^{-5 } }}}}∼{{{{ { 10}^{-3 } }}}}M) was employed for 10 minutes to measure coronary perfusate flow(CF) and coronary vascular sresistance(CVR) at a constant coronary perfusion pressure of 80 cmH2O Perfusate myocardial oxygen consumption(MVO2) and percent oxygen extraction(%EC2) were calcula-ted. In addition calcium contents in both perfusate samples were measured to calculate calcium release in coronary venous effluent. Caffeine significantly decreased CF and increased CVR during 10 minutes of caffeine perfusion regardless of dose of caffeine perfused exhibiting time-response. While % EO2 was significantly enhanced with caffeine MVO2 was markedly reduced. The coronary venous perfusate pH dcreased during the perfusion with caffeine. These changes were consistent with caffeine-induced metabolic acidosis. Calcium release appeared to be dose-dependent and high dose of caffeine greatly increased venous calcium release even 2 minutes after perfusion with carffeine. These finding in dicate that caffeine produced coronary vasoconst-riction with increased calcium release in isolated perfused guinea pig hearts. Additionaly this vasoconstrictor response mignt be due tin part to the direct actions of caffeine.

• The Journal of Korean Physical Therapy
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• 제18권5호
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• pp.1-11
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• 2006

Purpose: This study was to evaluate effects of myofascial release therapy for newborns and infants with congenital torticollis. Methods: In a two month period, thirty-six newborns and infants diagnosed with congenital muscular torticollis received treatment thirty times; then divided into a myofascial release group and stretching group. Crying frequency was used to measure the amount of crying time during treatment. Ultrasonography was used to measure the size of fibromatosis. Physical examinations were used to measure the degree of head tilting and rotation. Results: The results were as follows: 1. Crying frequency was significantly decreased in myofascial degree group. 2. The size of fibromatosis was not significantly decreased in ultrasonography. 3. Head tilt was significantly decreased in myofascial release group. 4. Rotation was not significantly increased in myofascial release and control group. Conclusion: The above results suggest that myofascial release therapy is helpful decreasing head tilt, crying frequency, and increasing head rotation.

• Biomolecules & Therapeutics
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• 제9권4호
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• pp.263-269
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• 2001

In this study, we tried to investigate whether poly-L-arginine (PLA) (MW 10,800) significantly affect mucin release from cultured hamster airway goblet cells and the mucosubstances of hypersecretory air-way goblet cells of rats. Confluent primary hamster tracheal surface epithelial (HTSE) cells were metabolically radiolabeled with $^3$H-glucosamine for 24 hr and chased for 30 min in the presence of varying concentrations of PLA to assess the effects on $^3$H-mucin release. Possible cytotoxicities of PLA were assessed by measuring both Lactate Dehydrogenate (LDH) release and by checking the possible changes on the morphology of HTSE cells during treatment. For in vivo experiment, hyperplasia of rat airway goblet cells and increase in intraepithelial mucosubstances were induced by exposing rats to SO$_2$ for 3 weeks and varying concentrations of PLA were administered inhalationally to assess the effects on the mucosubstances of airway goblet cells of rats. The results were as follows : (1) PLA significantly inhibited mucin release from cultured HTSE cells in a dose-dependent manner; (2) there was no significant release of LDH and no significant change on the morphology of cultured HTSE cells during treatment; (3) PLA also affected the intraepithelial mucosubstances of hypersecretory rats and restored them to the levels of control animals. We conclude that PLA inhibit mucin release from airway goblet cells without significant cytotoxicity and possibly normalize the hypersecretion of airway mucosubstances in vivo. This finding suggests that PLA might function as an airway mucoregulative agent.

• 상하수도학회지
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• 제8권2호
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• pp.25-34
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• 1994

In this research, investigations were made on the effect of type and load of organic substrate on phosphorus release. Reactors of three different sizes were operated, being fed on five kinds of organic substrates. The quantitative analyses were made on phosphorus release and substrate utilization under anaerobic condition. The molar ratios of the uptaken organic substrate to the released phosphorus were 0.5 with acetate, 0.6 with glucose, 0.8 with glucose/acetate, and 1.2 with glucose/acids, respectively. The phosphorus release was inhibited at the higher organic load than the normal at stead state. Both acetate and acids/glucose enhanced phosphorus release- as well as uptake-rate, however, the complete phosphorus removal was achieved after the microbial adaptation to the new environment. In case with acetate, operation was hampered by the poor sludge settleability and phosphorus uptake was not enough although the phosphorus release was active. But with milk/starch, the phosphorus release and uptake was well developed even though phosphorus release was not comparatively high. From this study, it was concluded that organic substrates, such as glucose seemed to be converted fatty acids after fast bio-sorption, followed by concurrent uptake of these acids by excess phosphorus removing bacteria.

• KSBB Journal
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• 제10권4호
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• pp.461-467
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• 1995

본 연구에서는 약물 전달체(키토산, 키토산.엽, 술폰화키토산)에 prednisolone을 분산시켜 제조한 고분자 매트릭스를 poly (DL-lactide)로 피막을 형성시킨 후 pH 1.2와 pH 7.4 인산염 완충용액에서 약물 방출실험을 하였다. 약물 방출시간은 pH 1.2에서 보다 pH 7.4에서 더 지연되였으며 약물 전달체의 함유량이 증가함에 따라 약물의 방출시간도 지연되었다. 피막된 고분자 매트릭스의 종류에 따라 지연된 약물의 방출시간은 키토산의 경우가 가장 길었으 며, 술폰화키토산, 키토산.염의 순셔였다. Monolith IC 고분자 매트릭스에 비해 2배 정도의 약물의 방출 지연성을 보인 피막된 monolithic 고분자 매트럭스 가 방출조절형 제제로서 더 바람직한 것으로 관찰되었다. 이러한 제형들은 초기 급격한 약물 방출속도의 변화를 억 제 하는 sustained release pattern 제 제 임을 확인할 수 있었다.

• 대한의생명과학회지
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• 제27권3호
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• pp.170-176
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• 2021

Thapsigargin (TG), a sarco/endoplasmic reticulum (ER) Ca²⁺-ATPase (SERCA) inhibitor, has been widely used as an agonist for platelet aggregation for decades. In this study, we investigated the effect of TG on the release of lactate dehydrogenase (LDH) for platelets and elucidated its mechanism. Platelet LDH release and platelet aggregation were increased by TG treatment; 1,000 nM of TG induced the complete lysis of platelets. Other agonists such as collagen (2.5 ㎍/mL), thrombin (0.1 U/mL), and ADP (10 mM) did not induce significant platelet LDH release despite platelet aggregation. Finally, we investigated the effects of pharmacological inhibitors on TG-induced platelet aggregation and LDH release. SP600125, a JNK inhibitor, and LY294002, a PI-3K inhibitor, inhibited TG-induced platelet LDH release but not platelet aggregation. Forskolin, an adenylyl cyclase activator, also inhibited LDH release without affecting platelet aggregation by TG. These results suggest that the TG-induced platelet aggregation was accompanied by LDH release but regulated by a different signaling pathway.

• Nuclear Engineering and Technology
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• 제26권1호
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• pp.78-89
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• 1994

콘크리트 구조물과 점토성 되메움재로 구성된 중저준위 방사성폐기물처분장 인공방벽으로 부터의 핵종유출률이 평가되었다. 네 종류의 유출경로가 고려되었으며, 각 유출경로가 방사성핵종의 총유출률에 미치는 영향이 분석되었다. 입력변수 간의 불확실도가 핵종유출률 분석에 미치는 영향을 정량화하기 위해 Latin Hypercube 표본추출 방법이 이용되었으며, 그 결과 얻어진 유출률 분포는 적합도검증을 통하여 결정되었다. 마지막으로 최대유출률의 범위가 통계적방법에 의해 95% 신뢰도수준으로 추정되었다.

• 공업화학
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• 제34권2호
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• pp.161-169
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• 2023

본 연구는 allbanggae starch (ABS), polyvinyl alcohol (PVA), alginic acid (SA)를 이용하여 naproxen (NP) 각인 starch 기반 다층 바이오소재를 제조하고, 물리화학적 특성과 약물 방출 제어 효과를 조사하였다. 또한, FE-SEM과 FT-IR 분석에 의해 제조한 다층 바이오소재의 특성을 조사하였다. 약물 방출 제어 효과와 경피 약물 전달 시스템의 적용 가능성을 확인하기 위해 NP 각인 다층 바이오소재로부터 NP 방출 특성을 사람의 체온인 36.5 ℃에서 다양한 pH buffer solution과 인공 피부를 이용하여 확인하였다. NP는 낮은 pH보다 높은 pH에서 1.3배 더 빠른 방출을 나타냈고, single-layer 바이오소재에서보다 multi-layer 바이오소재에서 약 4.0배 느린 방출이 일어남을 확인하였다. 인공 피부 방출에서도 동일하게 single-layer 바이오소재보다 multi-layer 바이오소재에서 약 4.0배 더 느린 약물 방출 결과를 나타내었다. 또한, double-layer와 triple-layer 바이오소재 모두 12시간 동안 지속적으로 NP가 방출되었음을 확인 하였다. NP 방출 mechanism을 규명하기 위해 수학적 모델링에 적용하여 비교했을 때, pH buffer solution에서의 방출은 Fickian diffusion mechanism, 인공 피부 방출은 empirical mechanism에 적합한 것을 확인하였다.

• 대한소아치과학회지
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• 제29권1호
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• pp.1-10
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• 2002

소아치과 임상에서 널리 사용되고 있는 심미수복 재료인 컴포머의 불소 유리와 수복물 인접 법랑질에 대한 항우식 효과를 평가해 보고자 본 연구를 시행하였다. 음성대조군으로 복합레진인 Z-100을 I군으로, 양성 대조군으로 글라스 아이오노머인 Fuji II LC를 IV군으로 설정하였으며, 실험군으로는 Dyract AP를 II군으로, F-2000을 III군으로 설정하였다. 불소 유리 량은 1일부터 7일까지는 매일, 그 후로는 각각 2일, 3일 또는 4일 간격으로 4주간 측정하였다. 또한 우전치의 순면에 동일한 와동을 형성하고 각 실험재료를 충전한 후 인공 우식을 유발시켜 항우식 효과 비교실험을 시행하였다. 음성 실험군인 I군은 불소유리를 하지 않았으며, IV군에서 전반적으로 가장 높은 불소 유리량을 나타냈다. II군과 III군은 IV군보다 전반적으로 낮은 불소 유리량을 보였으며, III군은 II군보다 불소 유리량이 많았다. 우식 병소의 관찰 결과 복합레진을 제외한 나머지 군에서는 수복물 인접부 우식 병소가 감소하는 양상을 나타냈으며, 컴포머 군인 F-2000과 Dyract AP간에는 별다른 차이를 관찰할 수 없었다.