• Title/Summary/Keyword: compound action potential

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Classification of HDAC8 Inhibitors and Non-Inhibitors Using Support Vector Machines

  • Cao, Guang Ping;Thangapandian, Sundarapandian;John, Shalini;Lee, Keun-Woo
    • Interdisciplinary Bio Central
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    • v.4 no.1
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    • pp.2.1-2.7
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    • 2012
  • Introduction: Histone deacetylases (HDAC) are a class of enzymes that remove acetyl groups from ${\varepsilon}$-N-acetyl lysine amino acids of histone proteins. Their action is opposite to that of histone acetyltransferase that adds acetyl groups to these lysines. Only few HDAC inhibitors are approved and used as anti-cancer therapeutics. Thus, discovery of new and potential HDAC inhibitors are necessary in the effective treatment of cancer. Materials and Methods: This study proposed a method using support vector machine (SVM) to classify HDAC8 inhibitors and non-inhibitors in early-phase virtual compound filtering and screening. The 100 experimentally known HDAC8 inhibitors including 52 inhibitors and 48 non-inhibitors were used in this study. A set of molecular descriptors was calculated for all compounds in the dataset using ADRIANA. Code of Molecular Networks. Different kernel functions available from SVM Tools of free support vector machine software and training and test sets of varying size were used in model generation and validation. Results and Conclusion: The best model obtained using kernel functions has shown 75% of accuracy on test set prediction. The other models have also displayed good prediction over the test set compounds. The results of this study can be used as simple and effective filters in the drug discovery process.

Early Gene Expression in Mouse Spleen Cells after Exposure to Nickel Acetate

  • Koh Jae-Ki;Kim Woo-Hyoung;Lee Chang-Ho;Nam Hae-Seon;Kim Sung-Ho;Woo Kee-Min;Lee Sang-Han
    • Toxicological Research
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    • v.22 no.2
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    • pp.95-102
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    • 2006
  • Exposure to soluble nickel compound produces toxic effects on immune system, but the mechanism of action remains to be elucidated. Differential gene expression was studied to understand the potential molecular mechanism responsible for acute toxicity induced by nickel acetate in spleen cells. We exposed mouse spleen cells to nickel acetate with a nontoxic dose ($40{\mu}M$) and then extracted total RNA at 6 h and 12 h after exposure. The RNA was hybridized onto 10K mouse oligonucleotide microarrays, and data were analyzed using GeneSpring 7.1. Nickel had a modest effects on expression of many genes, in the range of 1.3-3 fold. The expression profile showed time-dependent changes in expression levels of differentially expressed genes, including some important genes related to cell cycle, apoptosis and DNA repair. In hierarchical cluster analysis of duplicate experiments, 111 genes were screened out. Out of these, 44 genes showing time- dependent up-regulation (>1.5 fold) and 38 genes showing down-regulation (>1.5 fold) at all time points were chosen for further analysis. The change in the expression of three genes (GPX1, GADD45B and FAIM) after nickel treatment was validated using RT-PCR. As a rule, a number of genes appear to be coordinately regulated between cell survival and cell death from nickel toxicity. In conclusion, changes in the gene profile in the spleen after nickel treatment are complex and genes with diverse functions are modulated. These findings will be contributed to the understanding of the complicated biological effects of nickel.

A Case of Becker's Type Congenital Myotonia (Becker형 선천성 근긴장증 1례)

  • Yun, Sung-Hwan;Hah, Jung-Sang;Lee, Jun
    • Journal of Yeungnam Medical Science
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    • v.16 no.1
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    • pp.125-130
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    • 1999
  • Congenital myotonia is a hereditary disorder of the skeletal muscle. The most characteristic features of the disease are myotonia and variable muscular hypertrophy. Molecular biologic investigations have revealed that mutations in the gene of the human skeletal muscle chloride ion channel protein are a cause of the disease. The Becker's type congenial myotonia is clinically similar to the autosomal dominantly inherited congenital myotonia (Thomsen's disease). Both disorders are characterized electrophysiologically by increased excitability of muscle fibers. reflected in clinical myotonia. In general, Becker's type congenital myotonia is more severe than Thomsen's disease in muscular hypertrophy and weakness. The authors recently experienced a 25-year-old female patient who has no family-related disease history and who has conspicuous muscular hypertrophy and the stiffness with muscles which occurred from the age of 3 or 4. Clinically she showed the authors a percussion myotonia. On electrophysiological study, exercise and repetitive stimulation of the abductor digiti quinti muscle disclosed a decline in the compound muscle action potential. Biopsy of biceps muscle revealed enlargement of muscle fibers with marked nuclear internalization. After the oral taking the Mexiletine, the patient showed a favorable turn a little with her stiffness of muscles. So we authors are reporting one case of Becker's type congenital myotonia with review of literatures.

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A comprehensive review of the therapeutic and pharmacological effects of ginseng and ginsenosides in central nervous system

  • Kim, Hee Jin;Kim, Pitna;Shin, Chan Young
    • Journal of Ginseng Research
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    • v.37 no.1
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    • pp.8-29
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    • 2013
  • Ginseng is one of the most widely used herbal medicines in human. Central nervous system (CNS) diseases are most widely investigated diseases among all others in respect to the ginseng's therapeutic effects. These include Alzheimer's disease, Parkinson's disease, cerebral ischemia, depression, and many other neurological disorders including neurodevelopmental disorders. Not only the various types of diseases but also the diverse array of target pathways or molecules ginseng exerts its effect on. These range, for example, from neuroprotection to the regulation of synaptic plasticity and from regulation of neuroinflammatory processes to the regulation of neurotransmitter release, too many to mention. In general, ginseng and even a single compound of ginsenoside produce its effects on multiple sites of action, which make it an ideal candidate to develop multi-target drugs. This is most important in CNS diseases where multiple of etiological and pathological targets working together to regulate the final pathophysiology of diseases. In this review, we tried to provide comprehensive information on the pharmacological and therapeutic effects of ginseng and ginsenosides on neurodegenerative and other neurological diseases. Side by side comparison of the therapeutic effects in various neurological disorders may widen our understanding of the therapeutic potential of ginseng in CNS diseases and the possibility to develop not only symptomatic drugs but also disease modifying reagents based on ginseng.

Anticancer Effects of Curcuma C20-Dialdehyde against Colon and Cervical Cancer Cell Lines

  • Chaithongyot, Supattra;Asgar, Ali;Senawong, Gulsiri;Yowapuy, Anongnat;Lattmann, Eric;Sattayasai, Nison;Senawong, Thanaset
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.15
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    • pp.6513-6519
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    • 2015
  • Background: Recent attention on chemotherapeutic intervention against cancer has been focused on discovering and developing phytochemicals as anticancer agents with improved efficacy, low drug resistance and toxicity, low cost and limited adverse side effects. In this study, we investigated the effects of Curcuma C20-dialdehyde on growth, apoptosis and cell cycle arrest in colon and cervical cancer cell lines. Materials and Methods: Antiproliferative, apoptosis induction, and cell cycle arrest activities of Curcuma C20-dialdehyde were determined by WST cell proliferation assay, flow cytometric Alexa fluor 488-annexin V/propidium iodide (PI) staining and PI staining, respectively. Results: Curcuma C20 dialdehyde suppressed the proliferation of HCT116, HT29 and HeLa cells, with IC50 values of $65.4{\pm}1.74{\mu}g/ml$, $58.4{\pm}5.20{\mu}g/ml$ and $72.0{\pm}0.03{\mu}g/ml$, respectively, with 72 h exposure. Flow cytometric analysis revealed that percentages of early apoptotic cells increased in a dose-dependent manner upon exposure to Curcuma C20-dialdehyde. Furthermore, exposure to lower concentrations of this compound significantly induced cell cycle arrest at G1 phase for both HCT116 and HT29 cells, while higher concentrations increased sub-G1 populations. However, the concentrations used in this study could not induce cell cycle arrest but rather induced apoptotic cell death in HeLa cells. Conclusions: Our findings suggest that the phytochemical Curcuma C20-dialdehyde may be a potential antineoplastic agent for colon and cervical cancer chemotherapy and/or chemoprevention. Further studies are needed to characterize the drug target or mode of action of the Curcuma C20-dialdehyde as an anticancer agent.

Structure-Antagonistic Activity Relationships of an NK-2 Tachykinin Receptor Antagonist, L-659,877 and Its Analogues

  • Ha, Jong-Myung;Shin, Song-Yub;Hong, Hea-Nam;Suh, Duk-Joon;Jang, Tae-Sik;Kang, Shin-Won;Kuean, Sun-Jin;Ha, Bae-Jin
    • BMB Reports
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    • v.29 no.5
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    • pp.429-435
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    • 1996
  • To investigate the structure-antagonistic relationship of the cyclohexapeptide L-659,877, a selective NK-2 tachykinin receptor antagonist, seven analogues were chemically synthesized by a solid phase method. The agonistic and antagonistic activities of the analogues were evaluated by contraction assay using the smooth muscle of guinea pig trachea (GPT) containing the NK-2 receptor. It was shown that the aromatic ring of Phe at position 3 and the sulfur group of Met at position 6 in L-659,877 were essential for binding to the NK-2 receptor. Decrease in antagonistic activity of L-659,877 caused by substituting Leu for Nle at position 5 indicates that the ${\gamma}$ methyl group and side chain length of Leu plays an important role in its antagonistic action. Although the activity was slightly lower than L-659,877, cyclo $[{\beta}Ala^{8}]NKA(4-10)$ (analogue 1) showed potential antagonistic activity for the NK-2 receptor. It was confirmed that the expansion of the ring in L-659,877 by substitution of ${\beta}Ala$ for Gly at position 4 stabilized its conformation monitored by CD spectra. The results suggest that analogue 1 can be used as a new leader compound to design a more powerful, selective, and stable NK-2 receptor antagonist.

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Studies on the Mechanism of Action of the Gastric $H^{+}$+$K^{+}$ ATPase Inhibitor KH 3218

  • Cheon, Hyae-Cyeong;Kim, Hyo-Jung;Yum, Eul-Kgun;Cho, Sung-Yun;Kim, Do-Yeob;Yang, Sung-Il
    • Biomolecules & Therapeutics
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    • v.3 no.3
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    • pp.205-209
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    • 1995
  • The novel compound KH 3218 was synthesized and evaluated for its ability to inhibit the gastric H$^{+}$$K^{+}$ ATPase activity in vitro as well as to lessen gastric acid secretion in vivo. KH 3218 inhibited rabbit gastric H$^{+}$$K^{+}$ ATPase in a concentration and time dependent manner. $IC_{50}$/ value was estimated to be about 15 $\mu$M. The inhibition of the H$^{+}$$K^{+}$ ATPase by KH 3218 was blocked by sulfhydryl reducing agents, dithiothreitol or $\beta$-mercaptoethanol. The inhibition of the enzyme was not reversible by 50 fold dilution of the incubation mixtures, suggesting the irreversible nature of the inactivation. In the pylorus-ligated rift, KH 3218 reduced the total acid output as compared with the control. In addition, KH 3218 was capable of inhibiting H. pylori urease activity. These data suggest that KH 3218 is a potent inhibitor for H$^{+}$$K^{+}$ ATPase activity as well as for gastric acid secretion, and has a potential to be developed as a novel antiulcer agent.

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Paraquat Induces Apoptosis through a Mitochondria-Dependent Pathway in RAW264.7 Cells

  • Jang, Yeo Jin;Won, Jong Hoon;Back, Moon Jung;Fu, Zhicheng;Jang, Ji Min;Ha, Hae Chan;Hong, SeungBeom;Chang, Minsun;Kim, Dae Kyong
    • Biomolecules & Therapeutics
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    • v.23 no.5
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    • pp.407-413
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    • 2015
  • Paraquat dichloride (N,N-dimethyl-4-4'-bipiridinium, PQ) is an extremely toxic chemical that is widely used in herbicides. PQ generates reactive oxygen species (ROS) and causes multiple organ failure. In particular, PQ has been reported to be an immunotoxic agrochemical compound. PQ was shown to decrease the number of macrophages in rats and suppress monocyte phagocytic activity in mice. However, the effect of PQ on macrophage cell viability remains unclear. In this study, we evaluated the cytotoxic effect of PQ on the mouse macrophage cell line, RAW264.7 and its possible mechanism of action. RAW264.7 cells were treated with PQ (0, 75, and $150{\mu}M$), and cellular apoptosis, mitochondrial membrane potential (MMP), and intracellular ROS levels were determined. Morphological changes to the cell nucleus and cellular apoptosis were also evaluated by DAPI and Annexin V staining, respectively. In this study, PQ induced apoptotic cell death by dose-dependently decreasing MMP. Additionally, PQ increased the cleaved form of caspase-3, an apoptotic marker. In conclusion, PQ induces apoptosis in RAW264.7 cells through a ROS-mediated mitochondrial pathway. Thus, our study improves our knowledge of PQ-induced toxicity, and may give us a greater understanding of how PQ affects the immune system.

Anti-Diabetic Effect of Cotreatment with Quercetin and Resveratrol in Streptozotocin-Induced Diabetic Rats

  • Yang, Dong Kwon;Kang, Hyung-Sub
    • Biomolecules & Therapeutics
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    • v.26 no.2
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    • pp.130-138
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    • 2018
  • Quercetin and resveratrol are known to have beneficial effects on the diabetes and diabetic complication, however, the effects of combined treatment of these compounds on diabetes are not fully revealed. Therefore, the present study was designed to investigate the combined antidiabetic action of quercetin (QE) and resveratrol (RS) in streptozotocin (STZ)-induced diabetic rats. To test the effects of co-treated with these compounds on diabetes, serum glucose, insulin, lipid profiles, oxidative stress biomarkers, and ions were determined. Additionally, the activities of hepatic glucose metabolic enzymes and histological analyses of pancreatic tissues were evaluated. 50 male Sprague-Dawley rats were divided into five groups; normal control, 50 mg/kg STZ-induced diabetic, and three (30 mg/kg QE, 10 mg/kg RS, and combined) compound-treated diabetic groups. The elevated serum blood glucose levels, insulin levels, and dyslipidemia in diabetic rats were significantly improved by QE, RS, and combined treatments. Oxidative stress and tissue injury biomarkers were dramatically inhibited by these compounds. They also shown to improve the hematological parameters which were shown to the hyperlactatemia and ketoacidosis as main causes of diabetic complications. The compounds treatment maintained the activities of hepatic glucose metabolic enzymes and structure of pancreatic ${\beta}-cells$ from the diabetes, and it is noteworthy that cotreatment with QE and RS showed the most preventive effect on the diabetic rats. Therefore, our study suggests that cotreatment with QE and RS has beneficial effects against diabetes. We further suggest that cotreatment with QE and RS has the potential for use as an alternative therapeutic strategy for diabetes.

Clinical and Electrophysiological Changes after Open Carpal Tunnel Release: Preliminary Study of 25 Hands (수근관증후군 수술 전후 임상증상과 전기생리학적 검사소견의 변화: 25손을 대상으로 한 예비연구)

  • Yang, Ji Won;Sung, Young Hee;Park, Kee Hyung;Lee, Yeong Bae;Shin, Dong Jin;Park, Hyeon Mi
    • Annals of Clinical Neurophysiology
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    • v.16 no.1
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    • pp.21-26
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    • 2014
  • Background: Electrophysiological study has been known as a useful method to evaluate the therapeutic effect of operation in idiopathic carpal tunnel syndrome (CTS). The purpose of this study was to evaluate the clinical and electrophysiological changes after carpal tunnel release (CTR) compared to the preoperative results. Methods: We analyzed the changes of nerve conduction study (NCS) before and after minimal open carpal tunnel release in 18 patients (25 hands) with CTS. Follow-up study was performed over 6 months after operation. Results: Clinical improvement was seen in all cases after CTR. In contrast, electrophysiological improvement was various depending on the parameters; the mean median sensory latency and nerve conduction velocity (NCV) improved significantly (p = 0.001). The mean median motor latency also improved, but NCV and compound muscle action potential (CMAP) amplitude did not change. The extent of improvement was evident in moderate CTS, but not in severe CTS. Conclusions: In this preliminary study, all subjects who underwent CTR achieved a clinical relief along with a significant improvement of electrophysiological parameters such as median sensory latency, sensory NCV and median distal motor latency. After CTR, a number of cases with mild to moderate CTS showed a prominent improvement of clinical and electrophysiological parameters, while fewer improvements were seen in severe CTS, although it did not reach the statistical significance.