• Molecules and Cells
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• 제19권1호
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• pp.74-80
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• 2005

Stress is known to inhibit granule cell proliferation in the hippocampus. However, recent studies suggest that the commonly used dose of bromodeoxyuridine (BrdU) is insufficient to label all fractions of granule cells. Furthermore, stress-induced changes in BrdU availability may influence the labeling of newly born cells. To investigate whether changes in BrdU availability affect measurements of stress-induced granule cell proliferation, granule cell proliferation was assessed using injection of high doses of BrdU before and after restraint stress lasting 1 h. In addition, to determine whether stress-induced changes in plasma corticosterone levels were influenced by the BrdU, time-dependent changes in plasma corticosterone levels over 2 h after BrdU injection were compared with total accumulated plasma corticosterone levels [as determined by areas under the curve (AUC)]. Restraint stress significantly reduced the numbers of BrdU-labeled cells and clusters in the granule cell layer (GCL) of rats that received BrdU after stress, and decreases of similar magnitude were observed when the rats were given BrdU before stress. BrdU injection enhanced the stress-induced plasma corticosterone response, but there was no difference between the mean AUCs of plasma corticosterone levels of animals injected with BrdU before or after stress. These observations suggest that restraint stress decreases granule cell proliferation, and that this may be influenced by the extent and duration of plasma corticosterone increases rather than by changes in the availability of BrdU.

• 한국잡초학회지
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• 제18권4호
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• pp.341-347
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• 1998

물에 부상하여 확산 이동되어 약효를 내도록 만든 특수제형인 수면부상성입제(U-Granule)의 효과를 검토하였다. 일년생 화본과 잡초인 피의 방제 약제인 carbamate계 제초제 molinate와 일년생 광엽잡초 방제약제인 triazine계 제초제 simetryn, 그리고 다년생 잡초인 올방개에 효과가 있는 imazosulfuron을 혼합 제제하여 1996년 시험하였다. 1. 담수직파 포장에서 molinate+simertyn 수면부상성업제를 투척처리할 때 주성분이 이동하는 데는 약 5분이 소요되었다. 2. Molinate와 molinate+simetryn 수면부상성입제로 제제하여 처리했을 때 처리 지점으로부터의 거리별 농도는 두 약제간 큰 차이가 없었으며, 72시간 후 1m 지점에서 2.8ppm, 3m 지점에서 2.2ppm, 5m 지점에서 0.9ppm, 7m 지점에서 0.6ppm을 나타내었다. 7m 지점에서의 피 살초효과는 molinate+simetryn 수면부상성성입제가 molinate 단제보다 약 23% 높았다. 3. 담수직파포장에서 molinate+simetryn+imazosulfuron 수면부상성입제는 molinate+imazosulfuron 수면부상성입제에 비해 피에 대한 살초효과는 높았고 올방개에 대한 살초효과는 비슷하였다. 4. 수면부상성입제 시용시 molinate+simetryn+imazosulfuron UG는 처리지점으로부터 약 5m, molinate+Imazosulfuron UG는 처리지점으로부터 약 2m 지점까지만 경미한 약해가 나타났으나 후기에는 회복되어 큰 문제가 되지 않았다.

• 대한의생명과학회지
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• 제29권3호
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• pp.184-189
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• 2023

Normal activation of platelets and their aggregation are crucial during hemostasis process. It appears excessive or abnormal aggregation of platelets may bring about cardiovascular diseases like stroke, atherosclerosis, and thrombosis. For this reason, finding a substance that can regulate platelet aggregation or suppress aggregation will aid in the prevention and treatment of cardiovascular diseases. Artemisinin, a compound derived from Artemisia or Scopolia plants, has shown potential in various areas such as anticancer and Alzheimer's disease research. However, the specific role and mechanisms by which artemisinin influences platelet activation and thrombus formation are not yet fully understood. This study investigated the effects of artemisinin on platelet activation and thrombus formation. This study examined the effect of artemisinin on regulation of U46619-induced platelet aggregation, granule secretion. In addition, the effects of artemisinin on phosphorylation of PI3K/Akt and MAPK pathway involved in platelet aggregation was studied. As a result, artemisinin significantly downregulated of PI3K/Akt and MAPK pathway. In addition, artemisinin significantly reduced granule secretion, and platelet aggregation was inhibited by artemisinin. Therefore, we suggest that artemisinin is an anti-platelet substance that regulates PI3K/Akt and MAPK pathway and is valuable as a therapeutic and preventive agent for platelet-derived cardiovascular disease.

• Journal of Ginseng Research
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• 제4권1호
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• pp.96-103
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• 1980

The effect of granule size of dried red ginseng extract on physical characteristics on tablet such as hardness, color, yield and disintegration time was studied. A moisture proofing agent was found to be necessary to form granules without serious absorption of moisture. The result showed that decrease in particle size resulted increase of values in weight, hardness and disintegration time. The granule size of 60∼80 mesh was found to be optimum for proper color uniformity and other physical characteristics of tables.

• 공업화학
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• 제22권6호
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• pp.642-647
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• 2011

회전형 휘발성 산화장치(voloxidizer)와 200 g $U_3O_8$ 분말을 사용하여 초기 미세 입자층의 운동형태, 열처리 온도 및 시간, voloxidizer의 회전속도에 따른 다공성 그래뉼의 회수율과 특성을 분석하였다. 초기 미세 입자층의 운동형태에 따른 1 mm 이상의 그래뉼의 회수율은 rolling 운동 때보다 slumping 운동일 경우에 보다 높았다. 초기 미세 입자층이 rolling 운동형태인 경우에는 미세입자로부터 그래뉼이 생성됨에 따라서 slumping 운동형태로 변하며 slumping 빈도가 매우 높았다. 열처리 온도의 증가 및 10 h까지는 시간의 증가에 따라서 그래뉼의 회수율이 매우 크게 증가하였다. Slumping 운동형태를 보이는 초기 미세 입자층의 경우에 voloxidizer의 회전속도가 증가함에 따라서 그래뉼의 회수율 은 81.5에서 88.7%로 증가하였으나, 그래뉼 특성 측면에서 보면 회전속도가 2 rpm인 경우에 밀도, 파쇄강도, 구형도가 가장 높았다.

• 생약학회지
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• 제53권2호
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• pp.64-69
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• 2022

When blood vessels are damaged, a rapid hemostatic response should occur in order to lower blood loss and keep normal circulation, and platelet activation and aggregation are essential. Nevertheless, abnormal or excessive platelet aggregation can be a reason of cardiovascular diseases including thrombosis, atherosclerosis, and stroke. Therefore, the screening for a substance which can regulate platelet activation and suppress aggregation reaction is very important for treatment and prevention of cardiovascular diseases. Artemether is a methyl ether derivative of artemisinin, which is isolated from the antimalarial plant Artemisia annua, but research on platelet aggregation or its mechanisms is still insufficient. This study identified the effects of artemether on U46619-induced human platelet aggregation and their granule secretion (ATP and serotonin release). In addition, the effects of artemether on the phosphorylation of PI3K/Akt or MAPK, which are related to signal transduction in platelet aggregation, were studied. As the results, artemether significantly lowered PI3K/Akt and MAPK phosphorylation, which inhibited platelet aggregation through granule secretion (ATP and serotonin release) dose-dependently. Therefore, we suggest that artemether is an antiplatelet substance that regulates PI3K/Akt and MAPK pathway and is of value as a therapeutic and preventive agent for platelet-derived cardiovascular diseases.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2005년도 한국식물병리학회 임시총회 및 춘계학술발표회
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• pp.77-77
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• 2005

• Journal of Ginseng Research
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• 제45권4호
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• pp.490-497
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• 2021

Background and objective: Synthetic ginsenoside compounds G-Rp (1,3, and 4) and natural ginsenosides in Panax ginseng 20(S)-Rg3, Rg6, F4 and Ro have inhibitory actions on human platelets. However, the inhibitory mechanism of ginsenoside Rk1 (G-Rk1) is still unclear thus, we initiated investigation of the anti-platelet mechanism by G-Rk1 from Panax ginseng. Methodology: Our study focused to investigate the action of G-Rk1 on agonist-stimulated human platelet aggregation, inhibition of platelet signaling molecules such as fibrinogen binding with integrin α_IIbβ₃ using flow cytometry, intracellular calcium mobilization, fibronectin adhesion, dense granule secretion, and thromboxane B2 secretion. Thrombin-induced clot retraction was also observed in human platelets. Key Results: Collagen, thrombin, and U46619-stimulated human platelet aggregation were dose-dependently inhibited by G-Rk1, while it demonstrated a more effective suppression on collagen-stimulated platelet aggregation using human platelets. Moreover, G-Rk1 suppressed collagen-induced elevation of Ca²⁺ release from endoplasmic reticulum, granule release, and α_IIbβ₃ activity without any cytotoxicity. Conclusions and implications: These results indicate that G-Rk1 possess strong anti-platelet effect, proposing a new drug candidate for treatment and prevention of platelet-mediated thrombosis in cardiovascular disease.

• 자연과학논문집
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• 제6권1호
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• pp.5-39
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• 1993

한국 해산 남조류(Cyanophyta) 의 목록을 작성하고 분류학적 위치를 확인하기 위하여 우리나라 전해역에서 채집된 남조류를 대상으로 형태분류학적 연구를 시도하였다. 그 결과 동정된 한국 해산 남조류는 총 3목 6과 20속 36종이며, 이 중 14종이 우리나라에서 그 생육이 처음으로 확인된 미기록종 (Chroococcus minutus ($K\"{u}$tzing) $N\"{a}$geli, Merismopedia punctata Meyen, Microcystis ichtyoblabe $K\"u$zing, Dermocarpa leibleiniae (Reinsch) Born. et Thur., Hydrocoleum confluens (Setchell et Gardner) Drouet, Lyngbya sordida (Zanard.) Gomont, Phormidium forveolarum (Mont.) Gomont, Phormidium hansgieri Schmidle, Skujaella hildebrandtii (Gomont.) de Toni, Sphaeronema lithophila (Ercegovic) Umezaki, Spirulina tenerrima $K\"u$tzing, Hormothamnion enteromorphoides Grunow, Michrochaete aeruginea Batters, Michrochaete grisea Thuret ex Born. et flah.)이었다. 본 연구에서는 간섭현미경과 위상차현미경을 이용하여 체형이 미소한 남조류의 현미사진을 작성하였다. 형태학적으로 분류된 각 종을 대상으로 세포내 함유물을 관찰하여 그 중 PHB ($poly-\SS$-hydroxybutyrate) granule의 존재 유무를 조사하였으며, Lyngbya confervoides, Lyngbya semiplena, Phormidium corium, Sirocoleum kurzii, Hormothanmnion enteromorphoides, Calothrix crustacea들은 PHB를 함유하고 있음이 확인되었다. 이 결과는 생리생화학적 특성을 기초로한 남조류의 분류체계를 정립하기 위한 자료로 활용될 수 있을 것이다.

• 대한의생명과학회지
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• 제25권2호
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• pp.123-130
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• 2019

Platelet aggregation is essential for hemostatic process in case of blood vessels damages. However, excessive platelet aggregation can cause cardiovascular disorders including atherosclerosis, thrombosis and myocardial infarction. Scopoletin is usually found in the roots of genus Scopolia or Artemisia, and is known to have anticoagulant and anti-malarial effects. This study investigated the effect of scopoletin on human platelet aggregation induced by U46619, an analogue of thromboxane $A_2(TXA_2)$. Scopoletin had anti-platelet effects by down-regulating $TXA_2$ and intracellular $Ca^{2+}$ mobilization ($[Ca^{2+}]_i$), the aggregation-inducing molecules generated in activated platelets. On the other hand, scopoletin increased the levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), which are known to be intracellular $Ca^{2+}$ antagonists. This resulted in inhibition of fibrinogen binding to ${\alpha}IIb/{\beta}_3$ in U46619-induced human platelet aggregation. In addition, scopoletin inhibited the release of adenosine trisphosphate (ATP) in dose-dependent manner. This result means that the aggregation amplification activity through the granule secretion in platelets was suppressed by scopoletin. Therefore, we demonstrated that scopoletin has a potent antiplatelet effect and is highly likely to prevent platelet-derived vascular disease.