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Charateristics of Voltage Dependent Calcium Uptake and Norepinephrine Release in Hypothalamus of DOCA-salt Hypertensive Rats

  • Lee, Jean-Young;Kim, Hae-Jung;Jung, Eun-Young;Chung, Hye-Joo;Ko, Kwang-Ho
    • Biomolecules & Therapeutics
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    • v.1 no.2
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    • pp.171-176
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    • 1993
  • Purpose of the present study was to clarify the role of noradrenergic neural activities in hypothalamus for either triggering or maintaining hypertension in deoxycorticosterone (DOCA)-salt hypertensive rats. Two groups of animals were prepared: 1) normotensive Wistar rats and 2) DOCA-salt induced hypertensive rats. Voltage dependent $^{45}Ca^{++}$ uptake, endogenous norepinephrine release, and the catecholamine content in the hypothalamus of DOCA-salt hypertensive and normotensive Wistar rats were compared. Animals at 4, 6 and 16 week-old of two groups were sacrificed by decapitation and hypothalamus was dissected out. Voltage dependent calcium uptake and norepinephrine release were determined from hypothalamic synaptosomes either in low potassium or high potassium stimulatory condition by using $^{45}Ca^{++}$ isotope and HPLC-ECD technique. Degrees of voltage dependent $^{45}Ca^{++}$ uptake and norepinephrine release in hypothalamic synaptosomes of 16-week-old DOCA-salt hypertensive rats were significantly greater than those of age matched normotensive control rats. The norepinephrine and dopamine contents of hypothalamus were about the same in two groups of animals. These results suggest that the alteration of evoked norepinephrine release related to calcium uptake in hypothalamus may play a role in the maintenance of hypertension in DOCA-salt hypertensive rats.

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Evaluation on the Phosphate Uptake Rate of Green Algae under Diurnal Rhythm and Algae Control Method (일주기에 따른 녹조류의 인흡수율 및 조류제어방법 평가)

  • Jang Kam-Yong;Lim Kyoung-Mook;Noh Tae-Mok;Lee Hac-Su;Park Sung-Ha
    • Journal of Environmental Science International
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    • v.14 no.9
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    • pp.873-879
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    • 2005
  • This study was investigate to evaluate the phosphate uptake rate of green algae in relation to diurnal rhythm and algae control method. The phosphate uptake rates of Chlorella vulgaris and Ankistrodesmus convolutus increased in light period and decreased in dark period. On the contrary, those of Chlamydomonas sp. showed a peak in the late dark period. The differences among species in phosphate uptake in relation to diurnal rhythm were due to the severe competition among species and seemed to alleviate the competition for nutrient supplies. The compound of CellCaSi, Ca and Fe showed the effective removal of the phosphorus. The extracts from rice and barley straw exhibited a significant effect on the growth inhibition of Microcystis aeruginosa.

Estimation of Nutrients Transport in Kamak Bay using the Eco-hydrodynamic Model (생태계모델을 이용한 가막만의 영양염 거동 특성 평가)

  • 김동명
    • Journal of Environmental Science International
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    • v.12 no.7
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    • pp.745-751
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    • 2003
  • The three-dimensional eco-hydrodynamic model was applied to estimate the physical process in terms of nutrients and net uptake(or regeneration) rate of nutrients in Kamak Bay for scenario analysis to find proper management plan. The estimation results of the physical process in terms of nutrients shelved that transportation of nutrients is dominant in surface level while accumulation of nutrients is dominant in bottom level. In the case of dissolved inorganic nitrogen, the results showed that the net uptake rate was 0∼60 mg/㎡/day in surface level(0∼3m), and the net regeneration rate was 0.0∼10.0 mg/㎡/day in middle level(3∼6m) and above 10mg/㎡/day in bottom level(6m∼below). In the case of dissolved inorganic phosphorus, the net uptake rate was 0.0∼3.0 mg/㎡/day in surface level, and the net regeneration rate was 0.5∼1.5 mg/㎡/day in middle level and 1.0∼3.0 mg/㎡/day in bottom level. These results indicates that net uptake and transport of nutrients are occurred predominantly at the surface level and the net generation and accumulation are dominant at bottom level. Therefore, it is important to consider the re-supplement of nutrients due to regeneration of bottom water.

Natural Indigo Dyeing of Wool by the One Step Reduction/Dyeing Method (일단계 환원/염색에 의한 모직물의 천연인디고 염색)

  • Son, Kyung-Hee;Shin, Youn-Sook;Yoo, Dong-Il
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.3
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    • pp.508-517
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    • 2010
  • One-step reduction/dyeing method was optimized for wool dyeing with natural indigo dye in this study. The effects of reduction/dyeing conditions including dye temperature and time, the pH of bath, concentration of dye, and reducing agent on dye uptake and color were investigated. The dye uptake was higher with no addition of alkali. Dyeing was carried out through the use of only sodium hydrosulfite in the bath. The maximum dye uptake was obtained at $60^{\circ}C$ for 30min and the dyed fabrics appeared in the PB Munsell color range. Dye uptake improved with the increase of a natural indigo dye concentration with the same sodium hydrosulfite concentration. At a higher dye uptake, the fabric color became more purplish and the maximum absorption shifted from 660nm to 620nm. Color reproducibility was reliable with a color difference in the range of 0.41~1.43. Regardless of color strength, washing and dry cleaning fastnesses were good with a 4/5 rating, and fastnesses to rubbing and light were acceptable with a 3/4~4 rating.

Preliminary Study on the Toxicity and Transfer of Heavy Metals and Tributyltin to Seagrass Zostera marina (잘피의 광합성에 대한 중금속 및 TBT의 독성 영향과 중금속 흡수에 대한 연구)

  • Choi, Tae-Seob;Kim, Kwang-Young;Lee, Byeong-Gweon;Lee, Jung-Suk
    • ALGAE
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    • v.20 no.2
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    • pp.157-166
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    • 2005
  • Uptake kinetics of Cd and Zn by leaves and rhizome of the seagrass Zostera marina were examined in controlled laboratory radiotracer experiments. Subsequently, acute toxicity of Cd, Cu and TBT on photosynthetic quantum yield (ΔF/Fm’ of Z. marina were determined, and the differential sensitivities of rapid light curve (RLC) to those harmful substances were also compared. All measurements on photosynthetic activity were determined by chlorophyll a fluorescence method using pulse amplitude modulation (PAM). Metal uptake by Z. marina was saturated with increasing exposure time in leaves and rhizomes. Uptake of Zn by Z. marina was faster than that of Cd. Metal uptake rates in Z. marina decreased with the increase of dissolved metal concentrations and also with the increase of biomass. The adverse effect of TBT on effective quantum yield was stronger than other pollutants. Average acute toxicity on the RLC of the seagrass exposed to TBT and two heavy metals (Cd and Cu) was going to decrease as follows: TBT > Cd > Cu. Our preliminary results in this study suggested that Z. marina potentially can be used as a biomonitor of harmful substances contamination in coastal waters.

Effects of a Hwanggi-tang Ethanol Extract on Glucose Uptake and Metabolism in Murine Myotubes (근육세포주에서 당 흡수 및 대사 조절에 대한 황기탕 에탄올 추출물의 효과)

  • Jang, Chul-yong;Shin, Sun-ho;Shin, Yong-jeen
    • The Journal of Internal Korean Medicine
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    • v.41 no.4
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    • pp.599-611
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    • 2020
  • Objectives: The aim of this study was to evaluate the effects of Hwanggi-tang on glucose digestion, uptake, and metabolism in murine C2C12 myotubes. Methods: Hwanggi-tang was prepared according to the Dong-ui-bo-gam (≪東醫寶鑑≫) prescription by 70% ethanol extraction. The effect on glucose digestion was examined by determining the inhibitory effect of Hwanggi-tang on α-glucosidase activity. We also compared and verified the gene and protein expression of genes related to glucose uptake in C2C12 myotubes treated with Hwanggi-tang or insulin. Glucose metabolism was assessed by the expression levels of associated enzymes. Results: Hwanggi-tang caused a dose-dependent inhibition of α-glucosidase activity, induced glucose uptake by activation of the PI3K/Akt/mTOR pathway in the insulin signaling pathway, and promoted glucose oxidation and β-oxidation. Conclusions: Hwanggi-tang exerts an anti-diabetic effect on murine myotubes by inhibiting glucose digestion and inducing glucose uptake and consumption.

Effect of Propranolol on the $Ca^{++}$-regulation of Cardiac Sarcoplasmic Reticulum and Mitochondria (Propranolol이 심근 sarcoplasmic reticulum 및 mitochondria 의 $Ca^{++}$ 조절작용에 미치는 효과에 관한 연구)

  • 최수승
    • Journal of Chest Surgery
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    • v.19 no.2
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    • pp.197-208
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    • 1986
  • Propranolol is one of clinically useful antiarrhythmic agents and electrophysiologically classified as group II. And the negative inotropic effect which is not related to adrenolytic effect has been demonstrated with high concentration of propranolol. On the other hand, it has been well known that the calcium plays a central role in excitation-contraction coupling process of myocardium and also in electrophysiological changes of cell membrane. Author studies the effect of propranolol on calcium uptake and release in sarcoplasmic reticulum and mitochondria prepared from porcine myocardium to investigate the mechanism of action of propranolol on myocardium. The results are summarized as follow: 1] The maximum Ca++-uptake of sarcoplasmic reticulum is inhibited by propranolol in a dose dependent manner. 2] The release of calcium from sarcoplasmic reticulum is not affected by propranolol but with higher than 1x10-3 M of propranolol, rate of calcium release from sarcoplasmic reticulum is decreased. 3] Propranolol inhibits the maximum uptake and uptake rate of calcium in mitochondria non-competitively. [Ki = 6.21 x 10-4 M] 4] The rate of Na+ induced calcium release from mitochondrion shows a function of [Na+]2 and is inhibited by propranolol with the concentration significantly lower than that affect the calcium uptake in sarcoplasmic reticulum and in mitochondria [Ki = 2.91 x 10-5 M]. These results suggest that propranolol affects the intracellular calcium homeostasis which may considered to be one of the mechanism of action of propranolol on myocardium.

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Effect of Salviae-radix on oxidant-induced impairment of membrane transport function in renal tubules (Oxidant에 의한 신장세뇨관 물질이동계의 장애에 대한 단삼(丹參)의 효과)

  • Kim, Sang-Beum;Jeong, Ji-Cheon
    • The Journal of Internal Korean Medicine
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    • v.18 no.1
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    • pp.147-155
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    • 1997
  • This study was undertaken to determine whether Salviae-radix (SVR) exraction exerts benefical effect against oxidant-induced inhibition of tetraethylammonium (TEA) uptake which is actively secreted by renal proximal tubules. TEA uptake increased as function of incubation time to 60 min. When renal cortical slices were exposed to 50 mM $H_2O_2$, TEA uptake was significantly inhibited. The inhibition was significantly protected by addition of 0.5% SVR extraction. The benefical effect of SVR was dose-dependent over the concentration range of 0.1-1%; $H_2O_2$ (50 mM)-induced inhibition of TEA uptake was completely protected by 0.5-1% SVR extraction. $H_2O_2$ increased LDH release which was accompanied by an increase in lipid peroxidation in renal cortical slices. These changes were prevented by 0.5% SVR. These results suggest that SVR exerts benefical effect against oxidant-induced impairment of membrane transport function, this effect may be due to by an antioxidant action.

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Extracardiac Uptake of Thallium-201 during Myocardial Perfusion Imaging with Pharmaeologic Vasodilation (심근관류 스캔중에 나타난 Thallium-201의 심장외 국소적 섭취)

  • Choi, Chung-Il;Kwak, Dong-Suk;Chung, Byung-Cheon;Park, Moo-Keun;Lee, Jae-Tae;Lee, Kyu-Bo
    • The Korean Journal of Nuclear Medicine
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    • v.26 no.1
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    • pp.65-71
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    • 1992
  • Myocardial perfusion imaging with $^{201}Tl-chloride$ following exercise or vasodilator-induced hyperemia has been effective in detecting the presence of coronary artery disease. An increased lung uptake of thallium has been reported as a sensitive marker of severe and extensive coronary artery disease and associated with poor prognosis. Thallium has also been noted to concentrate in a variety of malignant lesions. We report 5 cases of extracardiac uptake of thallium during myocardial perfusion scan with pharmacologic vasodilation. Accumulation of thallium was found in the lesions of a breast cancer, a lung cancer, a Castleman's disease and 2 cases of thymoma. We believe that the presence of focal extracardiac uptake of thallium during myocardial perfusion scan should suggest the need for further clinical evaluation to detect the tumor and must differentiate the increased lung uptake of thallium due to left ventricular dysfunction in coronary artery disease.

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Application of Oxygen Uptake Rate Measured by a Dynamic Method for Analysis of Related Fermentation Parameters in Cyclosporin A Fermentation:Suspended and Immobilized Cell Cultures

  • Chun, Gie-Taek;Agathos, S.N.
    • Journal of Microbiology and Biotechnology
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    • v.11 no.6
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    • pp.1055-1060
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    • 2001
  • Experimental data for the on-line estimation of cell concentration and growth rate are presented. For this purpose, we utilized the on-line calculation of the oxygen uptake rate (OUR), which was derived from a liquid phase dynamic mass balance for the oxygen during the active growth phase in cyclosporin A (CyA) fermentation. The cell yield coefficient, based on the oxygen $(Y_{x/o})$for both suspended and immobilized cells of Tolypocladium inflatum, was estimated as $1.9 gDCW/gO_2$ from a very good linear correlation between the cell mass produced and the total oxygen consumed. The calculated yield showed a good agreement with the value of $(Y_{x/o})$ generated from the correlation between the cell growth rate and the oxygen uptake rate. In addition, further experimental data are given, which were also applied to determine the specific oxygen uptake rate of T. inflatum cells during the exponential phase of CyA fermentation. A theoretical basis for the analysis of these fermentation parameters is also provided.

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