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Effect of the Ag3PO4 on Staphylococcus aureus Growth and Human Immunity

  • Kim, Mi Kyung;Kim, Dae-Sik
    • Biomedical Science Letters
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    • v.24 no.1
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    • pp.30-34
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    • 2018
  • Silver (Ag) has been widely used in commercial products and medical fields since ancient times because of its antibacterial effect. It is harmless and non-toxic to the human body. For this reason, recent research has actively evaluated antimicrobial activity using silver (Ag). In this study, we investigated the inhibitory effect of a silver-based compound, silver phosphate ($Ag_3PO_4$) on the growth of Staphylococcus aureus and the activation of human immunity. First, the inhibitory effect of $Ag_3PO_4$ on the growth of Staphylococcus aureus was confirmed by a growth curve and a colonyounting method. As a result, the growth inhibitory effect increased as the concentration of $Ag_3PO_4$ increased. Specifically, treatment with $5{\mu}g/mL$ of $Ag_3PO_4$ resulted in no bacteria growth, and the colony-counting method showed a remarkable inhibition. In addition, the expression of cytokine IL-8 by $Ag_3PO_4$ was examined to investigate the cellular immune system activation by $Ag_3PO_4$. After pretreatment of Staphylococcus aureus for 1 hour with $50{\mu}g/mL$ $Ag_3PO_4$, an increased IL-8 mRNA expression resulted. In cells treated with $Ag_3PO_4$, we found that the expression of IL-8 was enhanced in a time-dependent fashion compared to non-treated cells. These results indicate that $Ag_3PO_4$ induces antimicrobial activity against Staphylococcus aureus and activates human immunity. These results are expected to contribute to the future study of the mechanism of silver (Ag) and silver-based compounds in relation to antibacterial activity.

Hotwater Extract of Hovenia dulcis Peduncle Improves Exercise Performance and Anti-fatigue Effect in Mice (헛개나무 열매 열수추출물 투여에 의한 생쥐의 지구력 운동 수행 능력 향상 및 피로개선 효과)

  • Na, Chun-Soo;Hong, Cheol Yi;Na, Dae-Seung;Kim, Jin Beom;Yoon, Sun Young;Lee, Sang-Bum;Dong, Mi-Sook
    • Korean Journal of Pharmacognosy
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    • v.44 no.1
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    • pp.83-90
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    • 2013
  • The aim of this study was to evaluate the effect of hot water extract of peduncle obtained from Hovenia dulcis Thunb (HD) which is commercially developed for the protective effect on the alcoholic hepatotoxicity, on the endurance capacity for weight loaded forced swimming mice. The swimming times to exhaustion in mice fed 100 and 200 mg/kg HD for 2 weeks were prolonged 3.6 and 3.7 fold, and for 4 weeks 1.9 and 2.7 fold compared with each vehicle control ($42.8{\pm}20.5$ min and $67.7{\pm}47.8$ min, for 2 and 4 weeks), respectively. Blood biochemical parameters for ALT, AST, creatinine and BUN were not significantly different between from HD fed or control mice. Although HD fed mice swam over 2 fold longer time than vehicle control mice at 4 weeks, blood biomarkers of physical fatigue such as glucose, triglyceride and free fatty acid, lactate were not significant different and even tended to ameliorate. Hepatic lipid peroxidation and SOD activity did not significantly change in HD fed- and vehicle control exhausted swimming mice at 2 or 4 weeks. However, catalase activity in HD-fed mice was significantly increased in a dose-dependent manner compared with vehicle control mice. The present study indicates that HD improved physical fatigue and exercise performance in mice. Therefore, it has a potential for the pharmacological effect of anti-fatigue.

Effect of Benincasae Semen on Cultured Mouse Cerebral Neurons Damaged by Streptozotocin (동과가 Streptozotocin에 의해 손상된 대뇌신경세포에 미치는 영향)

  • Lee Whan Bong;Lee Kang Chang;Lee Ki Nam;Hong Gi Youn;Suk Seung Whan;Cho Chung Cu;Jung Sean Kwan;Hur Jung Mu;Lee Sang Bark;Seo Eun A;Song Ho Jun;Lee Young Chan;Park Seung Taeck
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.3
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    • pp.584-587
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    • 2002
  • It has been suggested that oxidative stress may play an important role in the pathogenesis of diabetic complications. The purpose of this study was to examine the oxidative stress of streptozotocin(STZ) in the cultured mouse cerebral neurons and the preventing effect of vitamin E and and Benincasae Semen(BS) on STZ-induced neurotoxicity. Cytotoxic effect of STZ and neuroprotective effect of antioxidant and BS were performed by MTT assay. 30 μM STZ decreased cell viability in dose-and time-dependent mannner, and vitamin E and BS diminished STZ-induced neurotoxicity in these cultures. From above the results, STZ has toxic effect. and antioxidants, vitamin E or herb extract of BS is very effective against STZ-induced neurotoxicity in cultured cerebral neurons of neonatal mouse.

Antidepressant effect of the extracts of Subi-jeon, a Korean medicinal prescription (수비전(壽脾煎) 추출물의 항우울 효과에 관한 연구)

  • Han, Yoon-Seoung;Lee, Sang-Taek;Shim, Sang-Min;Kim, Geun-Woo;Kim, Ju-Ho;Kim, Kyeong-Ok;Kim, Hun-Il;Koo, Byung-Soo
    • Journal of Oriental Neuropsychiatry
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    • v.16 no.1
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    • pp.171-183
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    • 2005
  • Objective : The Korean famous medicinal prescription of Subi-jeon was investigated for their antidepressant effects by tail suspension test, hot plate test, reserpine-induced hypothermia test. In addition, the monoamine oxidase activity was determined in vivo. Methods : The methanol extract reduced dose-dependently the duration of immobility in the tail suspension test, by 31.4 and 34%(p<0.05) at doses of 500mg/kg and 1g/kg, respectively, compared with control group. In comparison with this, the effect of the water extract was very weak. Results : 1. In the hot plate test, the methanol extract potently increased the jump latency time(p<0.05) compared to the control group, exhibiting the inhibition rate of 197% and 256% at doses of 500mg/kg and 1g/kg(per os), respectively, which is more effective than the water extract. 2. Both extracts suppressed the fall of body temperature induced by reserpine(reserpine-induced hypothermia) in a dose-dependent manner, showing the less effect at lower doses and better effect at higher doses compared to the water extract. 3. Both extracts inhibited the brain monoamine oxidase activity in an in vivo assay compared to the control group, the activity of water extract was better than that of the methanol extract. Conclusion : The prescription of Subi-jeon can be useful for the prevention and treatment of depression.

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Pharmacokinetic-Pharmacodynamic Modeling for the Relationship between Glucose-Lowering Effect and Plasma Concentration of Metformin in Volunteers

  • Lee, Shin-Hwa;Kwon, Kwang-il
    • Archives of Pharmacal Research
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    • v.27 no.7
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    • pp.806-810
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    • 2004
  • Metformin is a biguanide antihyperglycemic agent often used for the treatment of non-insulin dependent diabetics (NIDDM). In this study, the pharmacokinetics and pharmacodynamics of metformin were investigated in Korean healthy volunteers during a fasting state for over 10 h. In order to evaluate the amount of glucose-lowering effect of metformin, the plasma concentrations of glucose were measured for a period of 10 h followed by the administration of metformin (oral 500 mg) or placebo. In addition, the concentration of metformin in blood samples was determined by HPLC assay for the drug. All volunteers were consumed with 12 g of white sugar 10 minutes after drug intake to maintain initial plasma glucose concentration. The time courses of the plasma concentration of metformin and the glucose-lowering effect were analyzed by nonlinear regression analysis. The estimated $C_{max}$, $T_{max}$, $CL_{t}$/F (apparent clearance), V/F(apparent volume of distribution), and half-life of metformin were 1.42$\{pm}$0.07 $\mu\textrm{g}$/mL, 2.59$\{pm}$0.18h, 66.12$\{pm}$4.6 L/h, 26.63 L, and 1.54 h respectively. Since a significant counterclock-wise hysteresis was found for the metformin concentration in the plasma-effect relationship, indirect response model was used to evaluate pharmacodynamic parameters for metformin. The mean concentration at half-maximum inhibition $IC_{50}$, $k_{in}$, $k_{out}$ were 2.26 $\mu\textrm{g}$/mL, 83.26 $H^{-1}$, and 0.68 $H^{-1}$, respectively. Therefore, the pharmacokinetic-pharmacodynamic model may be useful in the description for the relationship between plasma concentration of metformin and its glucose-lowering effect.

Anti-aging and Anti-oxidative Effect of Naesohwangryun-tang(NSHRT) (내소황련탕(內疎黃連湯)의 항노화 및 항산화 효능 연구)

  • Oh, Sol-Ra;Nam, Sang-Woo;Song, Young-Chae;Kim, Hee-Taek;Kim, Yong-Min;Lee, Chun-Il
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.34 no.4
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    • pp.12-23
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    • 2021
  • Objectives : This study is to investigate the anti-aging and antioxidant effects of Naesohwangryeon-tang(NSHRT) extract in Hs68 fibroblasts. Methods : The fibroblast cell line Hs68 cells were used and MTT analysis was performed to measure the cell viability of Naesohwangryeon-tang, and then MMP-1 was induced with the cytokine TNF-𝛼 to confirm the anti-aging effect through real-time PCR and ELISA. In addition, ROS was induced with the TNF-𝛼 to confirm the anti-oxidant effect through DCF-DA. The signaling pathway according to the antioxidant effect was performed by western blot. Results : Naesohwangryeon-tang did not show cytotoxicity at all concentrations(100-800㎍/㎖) treated on Hs68 cells, and the inhibitory effect of MMP-1 was also confirmed. In addition, it was confirmed that the intracellular ROS increased by TNF-α was decreased by Naesohwangryeon-tang, and it was confirmed that the expression of NQO1 was increased in a concentration-dependent manner of Naesohwangryeon-tang. Conclusions : These results suggest that Naesohwangryeon-tang can be used as an anti-aging material by demonstrating the anti-aging and antioxidant effects of Naesohwangryeon-tang.

Involvement of the spinal γ-aminobutyric acid receptor in the analgesic effects of intrathecally injected hypertonic saline in spinal nerve-ligated rats

  • Myong-Hwan Karm;Hyun-Jung Kwon;Euiyong Shin;Honggyoon Bae;Young Ki Kim;Seong-Soo Choi
    • The Korean Journal of Pain
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    • v.36 no.4
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    • pp.441-449
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    • 2023
  • Background: Hypertonic saline is used for treating chronic pain; however, clinical studies that aid in optimizing therapeutic protocols are lacking. We aimed to determine the concentration of intrathecally injected hypertonic saline at which the effect reaches its peak as well as the underlying γ-aminobutyric acid (GABA) receptor-related antinociceptive mechanism. Methods: Spinal nerve ligation (SNL; left L5 and L6) was performed to induce neuropathic pain in rats weighing 250-300 g. Experiment 1: one week after implanting the intrathecal catheter, 60 rats were assigned randomly to intrathecal injection with 0.45%, 0.9%, 2.5%, 5%, 10%, and 20% NaCl, followed by behavioral testing at baseline and after 30 minutes, 2 hours, 1 day, and 1 week to determine the minimal concentration which produced maximal analgesia. Experiment 2: after determining the optimal intrathecal hypertonic saline concentration, 60 rats were randomly divided into four groups: Sham, hypertonic saline without pretreatment, and hypertonic saline after pretreatment with one of two GABA receptor antagonists (GABAA [bicuculline], or GABAB [phaclofen]). Behavioral tests were performed at weeks 1 and 3 following each treatment. Results: Hypertonic saline at concentrations greater than 5% alleviated SNL-induced mechanical allodynia and had a significant therapeutic effect, while showing a partial time- and dose-dependent antinociceptive effect on thermal and cold hyperalgesia. However, pretreatment with GABA receptor antagonists inhibited the antinociceptive effect of 5% NaCl. Conclusions: This study indicates that the optimal concentration of hypertonic saline for controlling mechanical allodynia in neuropathic pain is 5%, and that its analgesic effect is related to GABAA and GABAB receptors.

Correction for Na Migration Effects in Silicate Glasses During Electron Microprobe Analysis (전자현미분석에서 발생하는 규산염 유리 시료의 Na 이동 효과 보정)

  • Hwayoung, Kim;Changkun, Park
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.4
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    • pp.457-467
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    • 2022
  • Electron bombardment to silicate glass during electron probe microanalysis (EPMA) causes outward migration of Na from the excitation volume and subsequent decrease in the measured X-ray count rates of Na. To acquire precise Na2O content of silicate glass, one should use proper analytical technique to avoid or minimize Na migration effect or should correct for decreases in the measured Na X-ray counts. In this study, we analyzed 8 silicate glass standard samples using automated Time Dependent Intensity (TDI) correction method of Probe for EPMA software that can calculate zero-time intercept by extrapolating X-ray count changes over analysis time. We evaluated an accuracy of TDI correction for Na measurements of silicate glasses with EPMA at 15 kV acceleration voltage and 20 nA probe current electron beam, which is commonly utilized analytical condition for geological samples. Results show that Na loss can be avoided with 20 ㎛-sized large beam (<0.1 nA/㎛2), thus silicate glasses can be analyzed without TDI correction. When the beam size is smaller than 10 ㎛, Na loss results in large relative errors up to -55% of Na2O values without correction. By applying TDI corrections, we can acquire Na2O values close to the reference values with relative errors of ~ ±10%. Use of weighted linear-fit can reduce relative errors down to ±6%. Thus, quantitative analysis of silicate glasses with EPMA is required for TDI correction for alkali elements such as Na and K.

Comparative Study of Korean Mistletoe Lectin and Bee Venom on the Anti-Cancer Effect and Its Mechanisms of Action in Hepatocellular Carcinoma Cells (상기생과 봉독이 간암 세포주 Hep G2에 대해 미치는 항암 기전 비교)

  • Kim, Sung-Uk;Kim, Bo-Ram;Heo, Kyung;Lim, Seong-Woo
    • The Journal of Internal Korean Medicine
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    • v.30 no.4
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    • pp.845-857
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    • 2009
  • Background and Objectives : Korean mistletoe lectin (Viscum album coloratum agglutinin, VCA) and bee venom (BV) have been reported to induce apoptosis in various cancer cell lines in vitro and to show antitumor activity against a variety of tumors in animal models. However, the comparative effect of VCA and BV on the anti-cancer effect and mechanisms of action has not been determined. In this study, the effect in a human hepatocellular carcinoma cell line, Hep G2 cells, was examined. Methods : Cytotoxic effects of VCA and BV on Hep G2 cells were determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay in litro. The apoptotic cell death was then confirmed by propidium iodide staining and DNA fragmentation analysis. The mechanisms of action were examined by the expression of anti-apoptotic proteins and activation of mitogen-activated protein kinases. The involvement of kinase was examined in VCA or BV-induced apoptosis by using kinase inhibitors. Results : VCA and BV killed Hep G2 cells in a time and dose-dependent manner. Treatment of Hep G2 cells with VCA activated poly (ADP-ribose) polymerase-1 (PARP-1) known as a marker of apoptosis, and mitogen-activated protein kinases signaling pathways including MAPK/ERK, p38 MAPK and JNK. BV also activated PARP-1, MAPK/ERK. and p38 MAPK but not JNK. The expression level of anti-apoptotic molecule, Bcl-X, was decreased by VCA treatment but not by BV. Finally, the phosphorylation level of ERM proteins involved in the cytoskeleton homeostasis was decreased by both stimuli. VCA-induced apoptosis was partially inhibited by in the presence of JNK and p38 inhibitor, but BV only by p38 inhibitor. Conclusions : VCA-induced apoptosis is dependent on the activation of p38 and JNK. while BV-induced apoptosis is mediated by p38 activation in Hep G2 cells.

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Resveratrol Inhibits Nicotinic Stimulation-Evoked Catecholamine Release from the Adrenal Medulla

  • Woo, Seong-Chang;Na, Gwang-Moon;Lim, Dong-Yoon
    • The Korean Journal of Physiology and Pharmacology
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    • v.12 no.4
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    • pp.155-164
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    • 2008
  • Resveratrol has been known to possess various potent cardiovascular effects in animal, but there is little information on its functional effect on the secretion of catecholamines (CA) from the perfused model of the adrenal medulla. Therefore, the aim of the present study was to determine the effect of resveratrol on the CA secretion from the isolated perfused model of the normotensive rat adrenal gland, and to elucidate its mechanism of action. Resveratrol (10${\sim}100{\mu}$M) during perfusion into an adrenal vein for 90 min inhibited the CA secretory responses evoked by ACh (5.32 mM), high $K^+$ (a direct membrane-depolarizer, 56 mM), DMPP (a selective neuronal nicotinic $N_n$ receptor agonist, 100${\mu}$M) and McN-A-343 (a selective muscarinic $M_1$ receptor agonist, 100${\mu}$M) in both a time- and dose- dependent fashion. Also, in the presence of resveratrol (30${\mu}$M), the secretory responses of CA evoked by veratridine 8644 (an activator of voltage-dependent$Na^+$ channels, 100${\mu}$M), Bay-K-8644 (a L-type dihydropyridine $Ca^{2+}$ channel activator, 10${\mu}$M), and cyc1opiazonic acid (a cytoplasmic $Ca^{2+}$-ATPase inhibitor, 10${\mu}$M) were significantly reduced. In the simultaneous presence of resveratrol (30${\mu}$M) and L-NAME (an inhibitor of NO synthase, 30${\mu}$M), the CA secretory evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyc1opiazonic acid were recovered to a considerable extent of the corresponding control secretion compared with the inhibitory effect of resveratrol alone. Interestingly, the amount of nitric oxide (NO) released from the adrenal medulla was greatly increased in comparison to its basal release. Taken together, these experimental results demonstrate that resveratrol can inhibit the CA secretory responses evoked by stimulation of cholinergic nicotinic receptors, as well as by direct membrane-depolarization in the isolated perfused model of the rat adrenal gland. It seems that this inhibitory effect of resveratrol is exerted by inhibiting an influx of both ions through $Na^+$ and $Ca^{2+}$ channels into the adrenomedullary cells as well as by blocking the release of $Ca^{2+}$ from the cytoplasmic calcium store, which are mediated at least partly by the increased NO production due to the activation of NO synthase.