• Title/Summary/Keyword: biphasic

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Effects of Cryopreservation on Ca2+ Signals Induced by Membrane Depolarization, Caffeine, Thapsigargin and Progesterone in Boar Spermatozoa

  • Kim, Joon-Chul;Li, Yuhua;Lee, Sunwoo;Yi, Young-Joo;Park, Chang-Sik;Woo, Sun-Hee
    • Molecules and Cells
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    • v.26 no.6
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    • pp.558-565
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    • 2008
  • Although the fertilizing ability of spermatozoa is greatly reduced after freezing, complete understanding of alterations induced by cryopreservation has not been elucidated. The present study evaluates the effects of cryopreservation on the $Ca^{2+}$ handling of boar spermatozoa using several sperm activators. Intracellular $Ca^{2+}$ signals from single spermatozoa were measured using confocal $Ca^{2+}$ imaging of unfrozen samples and of other spermatozoa after having been frozen. Elevation of the external $K^{2+}$ concentration elicited a three times larger $Ca^{2+}$ increase in fresh spermatozoa than in cryopreserved spermatozoa. Caffeine elicited $Ca^{2+}$ transients with some oscillations in the fresh spermatozoa, but not in the thawed spermatozoa. Depletion of the $Ca^{2+}$ store with thapsigargin induced a rapid rise in $Ca^{2+}$ in the control but generated a smaller increase of $Ca^{2+}$ after thawing. Exposure to progesterone induced a biphasic rise of the $Ca^{2+}$ level in the fresh spermatozoa only. Sperm viability was reduced by cryopreservation. Resting $Ca^{2+}$ levels in fresh and cryopreserved spermatozoa were similar. Longer incubation (2.5 h) of thawed spermatozoa partly recovered the $Ca^{2+}$ response to the interventions. These results suggest that cryopreservation reduces the responsiveness of spermatozoa to depolarization, modulators of the internal $Ca^{2+}$ store and progesterone in terms of the $Ca^{2+}$ signal, thus providing a possible mechanism for reduced fertility observed in cryopreserved boar spermatozoa.

AC Recordings of Antennal Responses in The Rice Brown Planthopper to Common Plant Volatile Chemicals (식물 휘발성 물질에 대한 벼멸구 촉각의 전기생리학적 반응)

  • 윤영남;장영덕
    • Korean journal of applied entomology
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    • v.33 no.1
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    • pp.19-25
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    • 1994
  • Electrophysiological recordings of antennal responses to common plant volatile chemicals in the rice brown planthopper, Niloparuota lugens (Homoptera: Delphasidae}, were examined. Volatile plant chemicals were generally credited with a major role In host plant location for food or egg laying by many insects feeding on plants as adults and/or as larvae. An mitial examination of extracellular responses has been conducted. Acton potentials recorded from the plaque organs were initially positive-going, biphaslc spikes and the background firing rate of the cells recorded ranged from 1 ~22 impulses/sec. A wide range of responses to changes in concentration of the test chemical was observed. The commonest response was a relatively small increase in exitation with increasing concentration beween 1 J.lg and 100).\g on the filter paper in syringe. Adtivity either peaked at 100 $\mug$ and remained virtually saturated at 1000 f19 or tended to decrease at the highest concentration.

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Pharmacokinetics of DWP302, a New Combined Ranitidine Preparations for Gastroduodenal Diseases (라니티딘을 함유한 새로운 위장질환 치료용 의약조성물(DWP302)의 약물동태)

  • 김영만;김동오;김영도;남권호;이성원;이주헌;김학형;유영효;박명환
    • YAKHAK HOEJI
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    • v.37 no.5
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    • pp.544-548
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    • 1993
  • The pharmacokinetics of DWP302, a new combined ranitidine preparation in rats and dogs was studied using HPLC. DWP302 was composed of ranitidine, sucralfate and tripotassium dicitrato bismuthate. Especially, this study was focused on the possibilities that the concomitant administration of either sucralfate or TDB may affect the absorption of orally administered ranitidine. Ranitidine and DWP302 were orally administered to rats at a dose of ranitidine 10mg/kg. Several rats showed the biphasic peak of plasma concentration. AUC$_{S_{0-8}}$ of ranitidine and DWP302 group were found to be 1040$\pm$109 and 945$\pm$124 ng.hr/ml, respectively, and there was no significant difference between both AUCs. In a cross-over study for dogs, $C_{max}$, t$_{1/2}$ beta and total AUC of ranitidine group were found to be 625.8$\pm$86.7 ng/ml, 2.80$\pm$0.28 hr and 1688$\pm$127 ng.hr/ml, and those of DWP302 group were 562.6$\pm$120.9 ng/ml, 3.05$\pm$0.30 hr and 1673$\pm$123 ng.hr/ml, respectively. There was no significant difference between those parameters, but Tmax of DWP302 group (1.69$\pm$0.31 hr) was significantly different from ranitidine group (1.13$\pm$0.26 hr). The results suggest that either sucralfate or TDB may affect the lag-time or rate of absorption of ranitidine but not the extent of absorption.

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Cell Motility Is Decreased in Macrophages Activated by Cancer Cell-Conditioned Medium

  • Go, Ahreum;Ryu, Yun-Kyoung;Lee, Jae-Wook;Moon, Eun-Yi
    • Biomolecules & Therapeutics
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    • v.21 no.6
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    • pp.481-486
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    • 2013
  • Macrophages play a role in innate immune responses to various foreign antigens. Many products from primary tumors influence the activation and transmigration of macrophages. Here, we investigated a migration of macrophages stimulated with cancer cell culture-conditioned medium (CM). Macrophage activation by treatment with CM of B16F10 cells were judged by the increase in protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX2). The location where macrophages were at 4 h-incubation with control medium or CM was different from where they were at 5 h-incubation in culture dish. Percentage of superimposed macrophages at every 1 h interval was gradually increased by CM treatment as compared to control. Total coverage of migrated track expressed in coordinates was smaller and total distance of migration was shorter in CM-treated macrophages than that in control. Rac1 activity in CM-treated macrophages was also decreased as compared to that in control. When macrophages were treated with CM in the presence of dexamethasone (Dex), an increase in COX2 protein levels, and a decrease in Rac1 activity and total coverage of migration were reversed. In the meanwhile, biphasic changes were detected by Dex treatment in section distance of migration at each time interval, which was more decreased at early time and then increased at later time. Taken together, data demonstrate that macrophage motility could be reduced in accordance with activation in response to cancer cell products. It suggests that macrophage motility could be a novel marker to monitor cancer-associated inflammatory diseases and the efficacy of anti-inflammatory agents.

A STUDY ON THE EFFECT OF ELECTRO-ACUPUNCTURE ON ORAL PAIN (전기침이 구강동통에 미치는 영향에 관한 연구)

  • Choi, Yong-Sung;Lee, Chang-Seop;Song, Hyeong-Geun;Lee, Sang-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.23 no.3
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    • pp.717-728
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    • 1996
  • The effects of electro-acupuncture on the pain threshold and the amplitude of dEMG(di-gastric EMG) evoked by the noxious electric stimulation on teeth and gingiva in dogs were studied. Experiments were carried out with 10 dogs weighing 5-8kg. Each animal was anestheticed with Entobar given intraperitoneally in an initial dose of 30mg/kg. Maintenance dose of 5mg/kg/hr was given through a cannula, in the femoral vein, as required to keep up light anesthesia. Bipolar stimulating wire electrodes, 0.1mm in diameter, insulated except for tips, were inserted into the upper canine and palatal gingiva. Rectangular aluminium plate electrodes (15$\times$5mm) were placed on acupuncture points, called Yin-Hsiang, located at both sides of the upper jaw. Rectangular biphasic current pulses of 2Hz, with a $250{\mu}sec$ duration, were delivered for 15 minutes. The dEMG activities were recorded from the anterior belly of the digastric muscle(one of the jaw opening muscles) using bipolar wire electrodes. The magnitude of the jaw opening reflex at different intensties of electro-acupuncture(1volt 4volt and 10volt) was estimated by averaging the 30 superimposed dEMGs recorded on an oscilloscope and audiomonitor. Data were analysed statistically with ANOV A and paired t-test. The obtained results were as follows: 1. Pain thresholds were increased 7.7 %, 15.4 %, 17.3 % in the teeth and 11.1 %, 19.0 %, 25.4 % in the gingiva as the intensities of electro-acupuncture increased incrementally. 2. Amplitudes of dEMG were decreaed 8.3%, 22.4%, 27.4% in the teeth and 9.8%, 36.5%, 42.2 % in the gingiva as the intensities of electro-acupuncture increased incrementally. 3. Inhibition of pain responses by the electroacupuncture was more effective in the gingiva than in the teeth.

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Effects of Substance P on the Cell Proliferation and IL-2 Production of T Lymphocyte (Substance P가 T 임파구의 세포증식과 IL-2 생산에 미치는 영향)

  • Moon, Jin-Kyun;Choi, Byung-Son;Lee, Seok-Cho;Kim, Hyung-Seop
    • Journal of Periodontal and Implant Science
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    • v.27 no.4
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    • pp.805-818
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    • 1997
  • Immune responses of periodontal tissue may be regulated by products of sensory afferent nerve endings such as neuropeptides. Substance P(SP), a tachykinin neuropeptide, has been previously reported to stimulate the activities of T lymphocyte. Therefore, I examined the role of SP in IL-2 production and cell proliferation by using a homogeneous line of T lymphocytes(Jurkat and HuT78). Cell proliferation rate was determined by [$^3H$]-thymidine incorporation test, and IL-2 was quantitated by the growth rate of CD4+ IL-2-dependent T lymphocyte line CTLL-2. SP stimulated cell proliferation of T lymphocytes at the concentration of $10^{-12}$ and $10^{-8}$M in a biphasic bell-shape dose-dependent manner. However, SP alone did not induce IL-2 release at the concentration range of $10^{-6}$ to $10^{-14}$M. The upregulation of IL-2 release was observed when $10^{-12}$M SP was applied together with mitogens such as Con A or PHA+PMA on T cell lines, especially on Jurkat. Con A or PHA+PMA demonstrated to increase the rate of cell proliferation of Jurkat, which had shown to produce much amount of IL-2 indicating that mitogen-induced cell proliferation might be partially influenced by released IL-2. It was concluded that regulatory effects of SP on the immune/inflammatory response could be mediated through the costimulatory upregulation of IL-2 production and increase of cell proliferation of T lymphocyte.

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Curcumin Stimulates Proliferation of Spinal Cord Neural Progenitor Cells via a Mitogen-Activated Protein Kinase Signaling Pathway

  • Son, Sihoon;Kim, Kyoung-Tae;Cho, Dae-Chul;Kim, Hye-Jeong;Sung, Joo-Kyung;Bae, Jae-Sung
    • Journal of Korean Neurosurgical Society
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    • v.56 no.1
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    • pp.1-4
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    • 2014
  • Objective : The aims of our study are to evaluate the effect of curcumin on spinal cord neural progenitor cell (SC-NPC) proliferation and to clarify the mechanisms of mitogen-activated protein (MAP) kinase signaling pathways in SC-NPCs. Methods : We established cultures of SC-NPCs, extracted from the spinal cord of Sprague-Dawley rats weighing 250 g to 350 g. We measured proliferation rates of SC-NPCs after curcumin treatment at different dosage. The immuno-blotting method was used to evaluate the MAP kinase signaling protein that contains extracellular signal-regulated kinases (ERKs), p38, c-Jun $NH_2$-terminal kinases (JNKs) and ${\beta}$-actin as the control group. Results : Curcumin has a biphasic effect on SC-NPC proliferation. Lower dosage (0.1, 0.5, $1{\mu}M$) of curcumin increased SC-NPC proliferation. However, higher dosage decreased SC-NPC proliferation. Also, curcumin stimulates proliferation of SC-NPCs via the MAP kinase signaling pathway, especially involving the p-ERK and p-38 protein. The p-ERK protein and p38 protein levels varied depending on curcumin dosage (0.5 and $1{\mu}M$, p<0.05). Conclusion : Curcumin can stimulate proliferation of SC-NPCs via ERKs and the p38 signaling pathway in low concentrations.

Effects of Electroacupuncture on the Modulation of Formalin-induced Pain in the Rat (흰쥐 족저에 Formalin 주입으로 유발된 통증반응에 대한 전침 효과)

  • 김재효;최동옥;김민선;박병림;손인철
    • The Journal of Korean Medicine
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    • v.23 no.2
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    • pp.97-107
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    • 2002
  • Objective : Acupuncture is a method used to treat many kinds of pain in oriental cultural medicine. Especially when hetero-segmental area acu-points are stimulated, the therapeutic effects of pain control have more critical properties than other methods of acupuncture. However, the mechanism of pain control by acupuncture is contradictory so far. The present study examined the effects of electroacupuncture (EA) applied to the acu-point of the hetero-segmental area on modulation of formalin-induced pain in Sprague-Dawley rats. Methods : In order to apply EA to acu-points in the plantar area of right forepaws, a pair of Teflon-coated stainless steel wires were implanted in HT 7 (Shin-Moon) and PC 7 (Dae-Reung) 7 days before the behavioral test. A behavioral test was performed by means of video camera after injection of 5% formalin ($50{\;}\mu\textrm{l}$) into the lateral plantar region of the left hind paw. EA was delivered by a constant DC current stimulator at 4~5 mA, 2 ms, and 10 Hz for 30 min. c-Fos protein expression was measured in the lumbar spinal cord at 2 hr and 4 hr after formalin injection. Results : Behavioral responses including favoring, flinching and biting occurred in the biphasic pattern, such as the 1st phase (0~5 min) and the 2nd phase (20~45 min) after formalin injection. However, EA (4~5 mA, 2 ms, 10 Hz) significantly inhibited the behavioral responses. Injection of formalin expressed c-Fos protein on the ipsilateral dorsal horn neurons in L3 - L5 and the expression was sustained more than 4 hrs after formalin injection. However, EA decreased c-Fos protein expression at dorsal horn neurons in the lumbar spinal cord till 4hrs after formalin injection. Conclusions : These results suggest that EA modulates formalin-induced pain and this inhibitory action may be elicited by the descending inhibitory system.

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Comparisons in Pharmacokinetic Profiles of New Platinum Coordination Complexes, KBP31705-C127 and KBP30603-901 with Cisplatin and Carboplatin (신규 백금착물 항암제 KBP31705-C127, KBP30603-901의 Cisplatin 및 Carboplatin과의 약동력학적 동태 비교)

  • 정인숙;이주선;허수정;김진숙;진창배;김동현;김명배;박경수;손연수
    • Biomolecules & Therapeutics
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    • v.4 no.4
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    • pp.349-353
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    • 1996
  • The present study examined pharmacokinetic profiles of KBP31705-Cl27 and KBP30603-901, new platinum coordination complexes synthesized as anticancer candidates, in comparison with two well-known platinum-containing anticancer agents, cisplatin and carboplatin in rats. Under sodium pentobarbital anesthesia of male Sprague-Dawley rats, urinary bladder, and femoral artery and vein were catheterized for urine collection, blood sampling and drug injection, respectively Following i.v. administration of cisplatin (2 mg/kg), KBP31705-C127 (2 mg/kg), carboplatin (20 mg/kg) or KBP30603-901 (20 mg/kg), blood samples were collected at 2, 4, 6, 8, 10, 15, 20, 30, 45, 60 and 120 minutes. Urine samples were collected at 1-hr interval for 4 hr. Platinum concentrations in plasma and urine were measured using an inductively coupled plasmamass spectrometer. The plasma concentration-time curves were biphasic for all drugs during the time period studied. Compared with cisplatin, KBP31705-C127 showed similar decay patters in the alpha- and betaphases with slightly lower plasma concentrations. Urinary platinum excretion for cisplatin and KBP31705-C 127 was 56 and 52% of the administered dose in 4 hr, respectively. With regard to carboplatin and KBP 30603-901, a similar decay pattern was also observed in the alpha-phase. The half life of KBP30603-901 in the beta-phase, however, was much longer than that of carboplatin, which was consistent with the urinary excretion results that 46 and 59% of the administered dose were excreted in the urine in 4hr, respectively. The results suggest that platinum coordination complexes are primarily excreted via the renal route and KBP30603-901 can elicit longer duration of action due to slower renal excretion compared to carboplatin.

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Fatty Acid Components of Hardy Kiwifruit (Actinidia arguta) as IL-4 Production Inhibitor

  • Park, Hye-Min;Son, Mi-Won;Kim, Dong-Hyun;Kim, Seon-Hee;Kim, Sung-Hoon;Kwon, Hak-Cheol;Kim, Sun-Yeou
    • Biomolecules & Therapeutics
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    • v.19 no.1
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    • pp.126-133
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    • 2011
  • The fruit of Actinidia arguta (AA) has been used mainly for the treatment of skin diseases, diuresis, diabetes mellitus and osteoporosis in Korean traditional medicine. It is known that AA (hardy kiwi) fruit extract has an effect on 2-chloro-1,3,5-trinitrobenzene-induced atopic dermatitis-like skin lesions in NC/Nga mice. Mode of action for it is associated with the modulation of biphasic Th1/Th2 cytokines. Furthermore, DA9102 containing AA is a herbal medicine currently under phase II clinical trial for atopic dermatitis in Korea. However, no active principles of AA on the decrease of Th2 cytokines including IL-4 and IL-10 have been identified. In this study, bioactivity-guided fractionation of an alcohol extract from the dried fruits of AA using ELISA assay for IL-4 production led to the isolation of $\alpha$-linolenic acid (I), linoleic acid (II), ethyl linolenate (III), ethyl linoleate (IV) and ethyl stearate (V) as the major active components. These compounds showed the down-regulatory effects of IL-4 production in A23187-stimulated RBL-2H3 cells without cytotoxicity.