• The Korean Journal of Pharmacology
• /
• v.32 no.3
• /
• pp.301-309
• /
• 1996

Since it has been reported that the depolarization-induced NE release is inhibited by activation of presynaptic $A_1-adenosine$ heteroreceptor in hippocampus, a large body of experimental data on the post-receptor mechanism of this process has been accumulated. But, the post-receptor mechanism of presynaptic $A_1-adenosine$ receptor on the NE release has not been clearly elucidated yet. Therefore, it was attempted to clarify the participation of $K^+-channel$ in the post-receptor mechanisms of the $A_1-adenosine$ receptor-mediated control of NE release in this study. Slices from rat hippocampus were equilibrated with $^3H-norepinephrine$ and the release of the labelled products was evoked by electrical stimulation (3 Hz, 5 $VCm^{-1}$, 2 ms, rectangular pulses), and the influence of various agents on the evoked tritium-outflow was investigated. Adenosine, in concentrations ranging from $1{\sim}30\;{\mu}M$, decreased the NE release in a dose-dependent manner, without affecting the basal rate of release. 4AP $(1{\sim}30{\mu}M)$, a specific A-type $K^+-channel$ blocker, increased the evoked NE release in a dose-related fashion, and the basal rate of release is increased by 10 and $30{\mu}M$. TEA $(1{\sim}10{\mu}\;M)$, a nonspecific $K^+-channel$ blocker, increased the evoked NE release in a dose-dependent manner without affecting basal release. The adenosine effects were significantly inhibites by 3 ${\mu}M$ 4AP and 10 mM TEA treatment. 4AP $(30{\mu}M)-$ and TEA (10 mM)-induced increments of evoked NE release were completely abolished in $Ca^{++} free, but these were recoverd in low $Ca^{++} medium. And the effects of $K^+-channel$ blockers in low $Ca^{++} medium were inhibites and abolishes by $Mg^{++} (4 mM) adding and TTX $(0.3{\mu}M)$ adding medium, respectively. These results suggest that the decrement of the evoked NE-release by $A_1-adenosine$ receptor is mediated by 4AP and TEA sensitive $K^+-channel$.

• Korean Journal of Ecology and Environment
• /
• v.33 no.2 s.90
• /
• pp.136-144
• /
• 2000

M. aeruginosa isolated from Lake Paldang was cultured in CB medium, and then each wet plants put into the cultured medium at a rate of 0.5 g and 2.5 g wet wt/l. There was slight inhibition by the input of cattail and iris of each 0.5 g wet wt/l cultured medium, but showed no reduction in algal growth in other flasks. Among the applied plants, ginkgo, pine needles, big cone pine, waterreed and water chestnut had an effect on inhibition of algal growth at the input of 2.5 g wet wt/l. Plants which were dried for 3 days at $50^{\circ}C$ introduced into the testing flask for 10days cultured at dose rates of 2.5 g/l. When chlorophyll a concentration was remarkably high as $802.6\;{\mu}g/l$ after five days, there was noticeably less chlorophyll compared with control at a rate of 98% by big cone pine, 96% by ginkgo, 95% by pine needles and 86% by rice straw, respectively. To examine the effect of plant extracts on algal growth, big cone pine and water chestnut were put to the amount of 1.25 g liquid extracts/l. Chlorophyll a concentration and cell density decreased to the extent of average 43% as compared with the beginning of experiment, but when concentration of chlorophyll a increased a most high, the inhibition of algal growth by liquid extracts did not affect at all. When a quantity of plant equivalent to 2.5 g liquid extracts/l inhibited the growth of algae by 95% after nine days.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.34 no.1
• /
• pp.86-91
• /
• 1989

Since most chemicals effect to the non-target organisms, present study was conducted to determine the effects of some herbicides to soybean nodule bacteria(Rhizobium japonicum) in vitro. Selective upland herbicides Alachlor, Linuron, Simazine and nonselective Paraquat were medicated to the YEMA media and survival rate of the bacteria in the medium was measured a week after incubation. Survival of soybean nodule bacteria in the media medicated with recommended concentration 400 ppm of Alachlor and Linuron were decreased significantly by 27.4 ％ and 57.8 ％, respectively. While little effect was observed in Simazine, a marked reduction of survival was observed in 200 ppm of Paraquat. Effects of Alachlor was different with isolates of the nodule bacteria. Isolate I -122 was relatively resistant and I -145 was more sensitive. than other isolates tested. Intermediate K-5 was the most resistant at the recommended dose and the survival dose was drastically reduced with increment of concentration. Nodule formation of the soybean plants was different with the varieties and isolates. The most nodulation was observed in the resistant isolates I -122 and K-S, for which the nodulation might be related with the resistance to the environmental stress factors.

• BMB Reports
• /
• v.28 no.6
• /
• pp.515-522
• /
• 1995

The effects of the thyroid hormone ($T_3$) on 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity were evaluated in a baby hamster kidney cell line, C100. The cells cultured in MEM were supplemented with 10% thyroid hormone-depleted fetal bovine serum (THDS-MEM) and had a 82.5% lower level of HMG-CoA reductase activity than the cells grown in a medium supplemented with fetal bovine serum (FBS-MEM). When $T_3$ was supplemented to THDS-MEM, the reduction of the reductase activity was blocked in a dose-dependent manner. In the cells grown in THDS-MEM containing $T_3$ at a concentration of $10^{-6}$ M, the level of HMG-CoA reductase activity was 91.8% relative to the cells grown in FBS-MEM. These changes in HMG-CoA reductase activity seemed to be at least partly due to the changes of HMG-CoA reductase mRNA levels. The level of HMG-CoA reductase mRNA in cells incubated in THDS-MEM decreased to 76.2% relative to the cells grown in FBS-MEM, while the level of reductase mRNA in cells incubated in THDS-MEM containing $T_3$ at a concentration of $10^{-6}$ M increased to 243.4% relative to the cells grown in FBS-MEM. The increase of HMG-CoA reductase mRNA level after $T_3$ treatment may have been due to the increased stability of reductase mRNA, because the transcriptional rate of the reductase gene did not change significantly in the presence or absence of $T_3$. These results indicate that $T_3$ stabilizes HMG-CoA reductase mRNA at the posttranscriptional level and regulates HMG-CoA reductase activity in a dose-dependent manner.

• The Korea Journal of Herbology
• /
• v.29 no.5
• /
• pp.45-53
• /
• 2014

Objectives : The purpose of the study is to test the antibacterial, anti-inflammatory and antioxidant effects of BPH, which is composed of Pini Densiflorae Nodi Lignum and Querci Acutissimae Fructus, Angelicae Gigantis Radix, Cnidii Rhizoma, Angelicae Dahuricae Radix, Angelicae Tenuissimae Radix. Method : Antibacterial and anti-inflammatory effects of BPH on Propionibacterium acnes, one of anaerobic bacteria species were evaluated by measuring the levels of 2,2-diphenyl-1-picrylhydrazyl (DPPH) elimination and lipid peroxidation. Result : When BPH was applied to CCD-986sk (Human normal fibroblast) to confirm the level of cytokine(tumor necrosis factor-alpha, interleukin-8), its level increased in proportion to that of BPH's concentration, which indicated dose-dependent relationship. Using the Disk diffusion to measure the bacterial growth inhibition zone varying BPH concentration, it was found that the antibacterial effect of BPH was less than that of erythromycin, the control group, but was higher than that of saline, and it increased with higher concentrations. In a liquid culture medium containing BPH, the growth rate of Propionibacterium acnes was decreased by more than 10% at 25% BPH. After adding P. acnes to THP-1 monocyte, and treated it with BPH, and measuring the concentration of TNF-a and IL-8, it was observed that the amount of TNF-alpha and IL-8 significantly decreased depending on the level of BPH concentration. The ability to eliminate DPPH increased with higher BPH concentration. The inhibition of lipid peroxidation was increased by BHT treatment in a dose-dependent manner. Conclusion : Using Propionibacterium acnes, an anaerobic bacteria, we confirmed that BPH has antibacterial, anti-inflammatory and antioxidant effects.

• Animal Bioscience
• /
• v.37 no.2
• /
• pp.210-217
• /
• 2024

Objective: This study investigated the efficacy of different concentrations of gelatin supplementation in long-term semen extender on boar semen quality during storage for 10 days at 17℃. Additionally, oxytocin was added to stored semen to enhance fertility. Methods: In Experiment 1, boar semen was collected, diluted with gelatin at concentrations between 0% and 2.5% (w/v) and mixed with a semen extender. Then, it was kept in a refrigerator at 17℃ and stored for 10 days. In Experiment 2, the sperm quality was examined after adding 0, 5, and 10 IU oxytocin per artificial insemination dose to the most effective semen extender from Experiment 1 and placing it in a refrigerator at 17℃ for 10 days. In Experiment 3, the fertility potential in terms of non-return rate and litter size was determined using the most effective solid-stored semen supplemented with oxytocin. Results: The results indicated that sperm quality decreased with increasing storage time (p<0.05). The sperm quality in terms of total motility, progressive motility, and viable sperm with intact acrosomes and high mitochondrial potential was the highest with 1.5% gelatin supplementation (p<0.001) on all days of storage. Treatment with oxytocin did not affect sperm quality (p>0.05). The non-return rate and litter size after insemination with semen supplemented with 1.5% gelatin and 10 IU of oxytocin after 8 to 10 days of storage were comparable to those of the control group (p>0.05). Conclusion: A semen extender as a solid medium supplemented with 1.5% gelatin successfully preserved boar semen for a long storage duration. Treatment with oxytocin did not affect sperm quality. In addition, the fertility capacity using 1.5% gelatin with 10 IU oxytocin and stored for 8 to 10 days was acceptable and comparable to that of short-term storage.

• Journal of Nutrition and Health
• /
• v.39 no.8
• /
• pp.742-747
• /
• 2006

This study was performed to investigate the lipolytic effects of Portulaca oleracea L. extract in 3T3-L1 adipocytes. The Portulaca oleracea L. was extracted with extrusion method using twin-screw extruder under $58{\sim}60rpm$ screw speed, $4{\sim}5kg/hr$ feed rate, $140^{\circ}C$ extrusion temperature. The lipolytic action of Portulaca oleracea L. extract was estimated by measuring the amount of glycerol and free fatty acids (FFA) released from 3T3-L1 adipocytes and by measuring the cellular lipid content in 3T3-L1 adipocytes. The hormone sensitive lipase (HSL) mRNA level was analyzed using quantitative real-time PCR. The Portulaca oleracea L. extract at 1 to $100{\mu}g/ml$ suppressed lipid accumulation. The release of glycerol and FFA into the medium, and the mRNA level of HSL were significantly increased by the addition of Portulaca oleracea L. extract at dose-dependent manner. In conclusion, the Portulaca oleracea L. extract was suggested to have the lipolytic effect through release of lipolytic products (FFA and glycerol) of triacylglyceride to the culture medium and suppression of lipid accumulation via up-regulation of HSL gene expression in 3T3-L1 adipocytes.

• Journal of Korean Society of Water and Wastewater
• /
• v.18 no.3
• /
• pp.377-384
• /
• 2004

In the present study, a feasibility of an advanced oxidation process using UV/Hydrogen peroxide($H_2O_2$) system equipped with a medium pressure lamp for secondary effluent reclamation was investigated. Initial concentration of $H_2O_2$ and pH were changed to determine the optimum operation condition for the system. The removal efficiency of color was than 80% with 14.3mg/L of initial $H_2O_2$ and 5 minute of contact time in the UV/$H_2O_2$ system. The color removal was analyzed using first-order reaction equation. The dependence of rate constant (k) on initial $H_2O_2$ represented the rational relationship with maximum value. Residual $H_2O_2$ caused increase of effluent COD, since analyzing agent, dichromate, reacted with $H_2O_2$ in the sample. Therefore, excess initial concentration of $H_2O_2$ would significantly affect effluent COD measurement. At pH variation experiment, both residual $H_2O_2$ and color showed peak in the neutral pH range with the same pattern. Effect of $H_2O_2$ dose also enhanced color removal but raised residual $H_2O_2$ problem in the continuous operation UV system. In conclusion, these results indicated that medium pressure UV/$H_2O_2$ system could be used to control color in the secondary effluent for reclamation and reuse.

• Journal of Pharmaceutical Investigation
• /
• v.39 no.6
• /
• pp.437-443
• /
• 2009

To develop a topical bioadhesive formulation of clotrimazole for enhanced transdermal delivery, hydroxypropyl methylcellulose gel containing permeation enhancer was formulated and permeation studies were carried out. The release characteristics of the drug from the gel formulation were examined according to the receptor medium, drug concentration, and temperature. The rate of drug release from the gel increased with increasing drug concentration and temperature. The activation energy (Ea) of drug permeation, which was calculated from the slope of log P versus 1/T plots, was 14.41kcal/mol for a 1%(w/w) loading dose. The enhancer, such as saturated, unsaturated fatty acids, pyrrolidones, propylene glycol derivatives, glycerides, and non-ionic surfactants, were incorporated onto the gels to increase the amount of drug permeation into the skin. Among the enhancers used, polyoxyethylene 2-oleyl ether showed the highest level of enhancement. These results show that clotrimazole gels containing polyoxyethylene 2-oleyl ether could be used for the enhanced transdermal delivery of clotrimazole.

• Journal of the Korean Applied Science and Technology
• /
• v.15 no.4
• /
• pp.11-20
• /
• 1998

The propagation of light radiation in a turbid medium is an important problem that confronts dosimetry of therapeutic laser delivery and the development of diagnostic spectroscopy. Scattered light is measured as a function of the position(distance r, depth z) between the axis of the incident beam and the detection spot. Turbid sample yields a very forward-directed scattering pattern at short range of position from source to detector, whereas the thicker samples greatly attenuated the on-axis intensity at long range of position. The portions of scattered light reflected from or transmitted throughphantom depend upon internal reflectance and absorption properties of the phantom. Monte Carlo simulation method for modelling light transport in tissue is applied. It uses the photon is moved a distance where it may be scattered, absorbed, propagated, internally reflected, or transmitted out of tissue. The photon is repeatedly moved until it either escape from or is absorbed by the phantom. In order to obtain an optimum therapeutic ratio in phantom material, optimum control the light energy fluence rate is essential. This study is to discuss the physical mechanisms determining the actual light dose in phantom. Permitting a qualitative understanding of the measurements. It may also aid in designing the best model for laser medicine and application of medical engineering.