• Title/Summary/Keyword: Systemic Model

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Saturable Disposition of Taurine in the Cerebrospinal Fluid of the Rat

  • Chung, Suk-Jae
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.11a
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    • pp.99-113
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    • 1996
  • Taurine, a ${\beta}$-amino acid, plays an important role as a neuromodulator and is necessary for the normal development of the brain. Since de novo synthesis of taurine in the brain is minimal and in vivo studies suggest that taurine does not cross the blood-brain barrier, the blood-cerebrospinal fluid (CSF) barrier is likely to play a role in taurine transport between the central nervous system and the systemic circulation. Therefore, we examined in vivo elimination of taurine from the CSF in the rat to characterize in vivo kinetics of elimination for taurine from the CSF is consistent with the in vitro study. Using a stereotaxic device, cannulaes were placed into the lateral ventricle and the cisterna magna of the rat. Radio-labelled taurine and inulin (a marker of CSF flow) were injected into the lateral ventricle, and the concentrations of the labelled compounds in the CSF were monitored for up to 3 hrs in the cisterna magna. The apparent clearance of taurine from CSF was greater than the estimated CSF flow (p<0.005), indicating that there is a clearance process in addition to the CSF flow. Taurine distribution into the choroid plexus was at least 10 fold higher than that found in other brain areas (e.g., cerebellum, olfactory bulb and cortex). When unlabelled taurine was co-administered with radio-labelled taurine, the apparent clearance of the labeled taurine was reduced (p<0.01), suggesting a saturable disposition of taurine from CSF. Distribution of taurine into the choroid plexus, cerebellum, olfactory bulb and cortex was similarly diminished, indicating that the saturable uptake of taurine into these tissues is responsible for the non-linear disposition. A pharmacokinetic model involving first order elimination and saturable distribution described these data adequately. The Michaelis-Menten rate constant estimated from in vivo elimination study is similar to that obtained in the in vitro uptake experiment Collectively, our results demonstrate that taurine is transported in the choroid plexus via a taurine is cleared from the CSF via a saturable process. This process may be functionally relevant to taurine homeostasis in the brain.

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Development of Program to improve the Positive Psychology Capital of University Student' and its Effects (대학생의 긍정심리자본 향상 프로그램 개발 및 효과 분석)

  • Jo, Yun-Seo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.4
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    • pp.529-546
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    • 2016
  • The aim of this study was to development a program to improve the positive psychological capital of university students and its effects. The program to improve the positive psychological capital of university students was developed based on the systemic counseling program development model. For this purpose, the program to improve the positive psychological capital was carried out a total of 6 times (90 minutes per session) once a week for 24 university students at "C"university located in Gangwon-do, which was divided into 2 groups. In this study, the data were collected through a pretest and a posttest and, data analysis was performed using SPSS 20.0 ver. Based on the results, the program to improve the positive psychology capital was effective in increasing the positive psychology capital. Finally, the implications of the results, as well as the significance and limitations of the present study are discussed.

Effects of Mirror Therapy on Motor Recovery Following a Stroke: A Meta-Analysis (거울치료가 뇌졸중 환자의 운동기능 회복에 미치는 영향: 메타분석)

  • Lee, Hee-Won;Jeon, Hye-Seon
    • Physical Therapy Korea
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    • v.19 no.2
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    • pp.48-58
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    • 2012
  • The objective of this study was to evaluate the effects of mirror therapy on motor function recovery following a stroke through a systemic review and meta-analysis. In total, nine of the 48 studies were identified from search engines between 1997 and 2011, as well as from a review of the reference lists of each identified study. The quality of each study was assessed using Jadad scale, and the effect size was calculated as a Cohen's effect size using MetaAnalyst (Beta 3.13). The overall effect size of the mirror therapy was 2.005 (95% confidence interval=1.041~2.970) in a random-effects model. This finding suggests that mirror therapy is beneficial for improving motor function following a stroke. The results from the subgroup analysis according to categorical variables were as follows: First, the effect size was larger for an onset time of less than 1 year (1.166) than for a duration of 1 year or more (.668). Second, the effect size of unpublished dissertations (1.610) was larger than published articles (1.221). Third, motor recovery of upper extremities (1.609) had a greater effect than motor recovery of lower extremities (.903). The major limitation of this study is the relatively small study population. Therefore, further individual studies of mirror therapy should be conducted in order to generalize the effects. In addition, mirror therapy supervised by a physical therapist should be recognized as a potential approach to manage motor function following a stroke and recommended to patients to improve their motor function.

The association Between Occupational Exposure to silica and Risk of Developing Rheumatoid Arthritis: A Meta-Analysis

  • Mehri, Fereshteh;Jenabi, Ensiyeh;Bashirian, Saeed;Shahna, Farshid Ghorbani;Khazaei, Salman
    • Safety and Health at Work
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    • v.11 no.2
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    • pp.136-142
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    • 2020
  • Background: Rheumatoid arthritis (RA) is an autoimmune disease with systemic inflammatory arthritis. This meta-analysis was conducted to examine the association between occupational exposure to silica and the risk of developing RA among different workers. Methods: In this meta-analysis, we searched relevant published studies using major electronic databases including Scopus, PubMed, ISI Web of Science, and Google Scholar search engine up to October 2019, and the references of retrieved articles were also checked for further possible sources. A random-effects model was used to account for heterogeneity among the results of the studies using the pooled odds ratios (ORs) and their 95% confidence intervals (CIs). The Q-statistic and I2 tests were calculated to assess heterogeneity between the studies. Results: The pooled calculation of OR indicated a significant association between occupational exposure to silica and risk of developing RA among different workers (OR = 2.59, 95% CI = 1.73 to 3.45). In addition, the pooled estimates of OR in smokers were statistically significant (OR = 2.49, 95% CI = 1.13 to 3.86). Conclusions: The findings of the present study reveal that occupational exposure to silica may be associated with increased risk of developing RA.

Action Mechanism of LB10522, a New Catechol-Substituted Cephalosporin (카테콜 치환체를 가진 세파로스포린계 항생제 LB10522의 작용기전)

  • Kim, Mu-Yong;Oh, Jeong-In;Paek, Kyoung-Sook;Kim, In-Chull;Kwak, Jin-Hwan
    • YAKHAK HOEJI
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    • v.40 no.1
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    • pp.102-111
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    • 1996
  • LB10522 is a new parenteral broad spectrum cephalosporin with a catechol moiety at C-7 position of beta-lactam ring. This compound can utilize tonB-dependent iron transp ort system in addition to porin proteins to enter bacterial periplasmic space and access to penicillin-binding proteins (PBPs) which are the lethal targets of ${\beta}$-lactam antibiotics. The chelating activity of LB10522 to metal iron was measured by spectrophotometrically scanning the absorbance from 200 to 900nm. When $FeCl_3$ was added, optical density was increased between 450 and 800nm. LB10522 was more active against gram-negative strains in iron-depleted media than in iron-replete media. This is due to the increased expression of iron transport channels in iron-depleted condition. LB10522 showed a similar activity against E. coli DC2 (permeability mutant) and E. coli DCO (wild type strain) in both iron-depleted and iron-replete media, indicating a minimal permeaility barrier for LB10522 uptake. LB10522 had high affinities to PBP 3 and PBP 1A, 1B of E. coli. By blocking these proteins, LB10522 caused inhibition of cell division and the eventual death of cells. This result was correlated well with the morphological changes in E. coli exposed to LB10522. Although the in vitro MIC of LB10522 against P. aeruginosa 1912E mutant (tonB) was 8-times higher than that of the P. aeruginosa 1912E parent strain, LB10522 showed a similar in vivo protection efficacy against both strains in the mouse systemic infection model. This result suggested that tonB mutant, which requires a high level of iron for normal growth, might have a difficulty in surviving in their host with an iron-limited environment.

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Therapeutic efficacy of the photoactivated sickle cells as novel drug delivery vehicle (약물전달 시스템 개발을 위한 여기된 광감응제의 응용)

  • Choe, Se-woon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.10a
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    • pp.958-960
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    • 2015
  • Sickle cells possess a unique combination of traits that may enable their use as models for novel synthetic tumor targeting controlled release drug carriers with the ability to treat disseminated tumors in advanced metastatic disease. In this study, we assess the ability of light-activated release sickle cells to enhance tumor delivery of the fluorescent dye calcein by delayed photolysis controlled release compared to free systemic administration of calcein. Sickle cells from mouse models of the disease were shown to preferentially accumulate in tumors compared to adjacent tissue, in 4T1 tumors in mice on a time scale about 12 hours. Sickle cells photosensitized with protoporphyrin IX achieved delayed release of 50% of contents 8-16 hours after photoactivation, which was deemed useful for in vivo delivery of cargo to tumors given the tumor accumulation time of the sickle cells. Sickle cells may be useful as a model for new synthetic drug carrier particles with delayed photolysis controlled release properties.

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Effects of Double Sexual Standards on the Relationship between Marital Satisfaction and Marital Stability (성에 대한 이중기준이 결혼 만족과 결혼 안정의 관계에 미치는 효과)

  • Cheong, Key-Won;Seong, Han-Gee
    • Korea journal of population studies
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    • v.29 no.1
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    • pp.71-95
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    • 2006
  • This study aimed at identifying the relationship between marital satisfaction and marital stability, with primary focus on the effect of double sexual standards on their relationship. Data from 370 married women of community and culture centers in Daegu Metropolitan area were analyzed through multi-step multiple regressions. Findings indicated that communication and intimacy were positively related to marital satisfaction, which showed strong effect on marital stability, and that double sexual standard weakened the relationship between marital satisfaction and stability. Relationship between sexual satisfaction and marital satisfaction were not statistically significant in the sample of married women. Construction of comprehensive and systemic theoretical model on marital stability was suggested for further study.

Protective effects of red ginseng extract against vaginal herpes simplex virus infection

  • Cho, Ara;Roh, Yoon Seok;Uyangaa, Erdenebileg;Park, Surim;Kim, Jong Won;Lim, Kyu Hee;Kwon, Jungkee;Eo, Seong Kug;Lim, Chae Woong;Kim, Bumseok
    • Journal of Ginseng Research
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    • v.37 no.2
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    • pp.210-218
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    • 2013
  • Numerous studies have suggested that Korean red ginseng (KRG) extract has various immune modulatory activities both in vivo and in vitro. In this study, we used a mouse model to examine the effects of orally administered KRG extract on immunity against herpes simplex virus (HSV). Balb/c mice were administered with 100, 200, and 400 mg/kg oral doses of KRG extract for 10 d and then vaginally infected with HSV. We found that KRG extract rendered recipients more resistant against HSV vaginal infection and further systemic infection, including decreased clinical severity, increased survival rate, and accelerated viral clearance. Such results appeared to be mediated by increased vaginal IFN-${\gamma}$ secretion. Moreover, increased mRNA expression of IFN-${\gamma}$, granzyme B, and Fas-ligand was identified in the iliac lymph node and vaginal tracts of KRG extract treated groups (200 and 400 mg/kg). These results suggest that the activities of local natural killer cells were promoted by KRG extract consumption and that KRG may be an attractive immune stimulator for helping hosts overcome HSV infection.

Effect of Lactic Acid Bacteria (Lactobacillus acidophilus, Streptococcus thermophilus, Bsfidobacterium bifidum) on the Enhancement of the Production of Nitric Oxide and TNF-$\alpha$ in RAW 264.7 Macrophage Cell (RAW 264.7 대식세포에서의 유산균에 의한 Nitric Oxide와 $TNF-{\alpha}$의 생성 증가 효과)

  • Park So Hee;Chung Myung Jun;Kim Soo Dong;Baek Dae Heoun;Kang Byoung Yong;Ha Nam Joo
    • YAKHAK HOEJI
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    • v.49 no.6
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    • pp.459-464
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    • 2005
  • The immune reinforcement of the probiotic lactic acid bacteria Lactobacillus acidophilus, Streptococcus thermophilus and Bifidobacterium bifidum was studied in RAW 264.7 cell line treated with diluted solution (dilution to $2^{5}$) of the supernatnats of lactic acid bacteria. RAW 264.7 cell line was used as a macrophage model to assess the effects of lactic acid bacteria on the production of nitric oxide (NO) and cytokine tumor necrosis factor (TNF)-$\alpha$ and cell morphological changes. The production of NO and TNF-$\alpha$ were largely affected by lactic acid bacteria in dose-dependent manner in 24 or 48 hr cultures and cell morphological changes were also largely affected by lactic acid bacteria. Especially Bifidobacterium bifidum differentially stimulated the production of NO and TNF-$\alpha$. NO production was increased by Bifidobacterium bifidum 25 $\mu$l/ml more than LPS (20 ng/ml) control, and TW-$\alpha$ by Bifidobacterium bifidum 6.25 $\mu$l/ml more than LPS (10 ng/ml) control. The in vitro approaches employed here should be useful in further characterization of the effects of lactic acid bacteria on systemic immunity.

Influence of Phenobarbital on the Hepatic Clearance of Organic Anionic Drugs in Rats - On the Basis of Pharmacokinetics of Indocyanine Green - (Rat에 있어서 Phenobarbital이 유기음이온성 의약품의 간클리어란스에 미치는 영향 - Indocyanine Green의 체내동태를 중심으로 -)

  • Lee, Yong-Bok;Shin, Sang-Chul;Koh, Ik-Bae
    • Korean Journal of Clinical Pharmacy
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    • v.3 no.1
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    • pp.31-43
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    • 1993
  • The influence of phenobarbital(PB) pretreatment(75mg/kg/day, Lp. for 4 days) on the hepatic clearance of indocyanine green(ICG) as a model compound of organic anionic drugs was investigated in rats in order to elucidate the relative contributions of change in the hepatic blood flow versus increase in the hepatic intrinsic activity to remove ICG due to PB pretreatment. ICG(1mg/kg) was injected single bolus via femoral or portal vein to the control and the PB-pretreated rats. The initial hepatic uptake clearance$(V_{d.c.}K_{12})$ obtained from plasma concentration-time data was increased by $38.4\% in the PB-pretreated rats, which may be due to the increased hepatic blood flow by PB pretreatment. Using a pharmacokinetic approach, hepatic blood flows were estimated of 67.5ml/min/kg in control rats and 91.9ml/min/kg in PB-pretreated rats. They were in good agreement with other's blood flow estimates observed experimentally. It may be concluded that the $38\%$ increased initial hepatic uptake clearance of ICG was due to the $36\%$ increased hepatic blood flow with phenobarbital, and that the increased hepatic blood flow and the activated hepatic intrinsic clearance with phenobarbital contributed to $49\%\;and\;51\%$ of the increased systemic clearance of ICG, respectively.

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