• Title/Summary/Keyword: Drug Distribution

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Interactions of Cationic Drugs and Cardiac Glycosides at the Hepatic Uptake Level: Studies in the Rat in Vivo, Isolated Perfused Rat Liver, Isolated Rat Hepatocytes and Oocytes Expressing oatp2

  • Dirk K.F.Meijer;Jessica E.van Montfoort
    • Archives of Pharmacal Research
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    • v.25 no.4
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    • pp.397-415
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    • 2002
  • This paper deals with a crucial mechanism for interaction of basic drugs and cardiac glycosides at the hepatic uptake level. Available literature data is provided and new material is presented to picture the differential transport inhibition of bulky (type2) cationic drugs by a number of cardiac glycosides in rat liver. It is shown that the so called organic anion transporting peptide 2 (oatp2) is the likely interaction site: differential inhibition patterns as observed in oocytes expressing oatp2, could be clearly identified also in isolated rat hepatocytes, isolated perfused rat liver and the rat in vivo. The anticipation of transport interactions at the hepatic clearance level should be based on data on the relative affinities of interacting substrates for the transport systems involved along with knowledge on the pharmacokinetics of these agents as well as the chosen dose regimen in the studied species. This review highlights the importance of multispecific tranporter systems such as OATP, accommodating a broad spectrum of organic compounds of various charge, implying potential transport interactions that can affect body distribution and organ clearance.

Development of Drug-Loaded PLGA Microparticles with Different Release Patterns for Prolonged Drug Delivery

  • Choi, Yeon-Soon;Joo, Jae-Ryang;Hong, Areum;Park, Jong-Sang
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.867-872
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    • 2011
  • For the prolonged delivery and sustained release rates of low molecular weight drugs, poly(lactic-co-glycolic acid) (PLGA) microparticles containing the drug SKL-2020 have been investigated. On increasing polyvinyl alcohol (PVA) concentration (from 0.2% to 5%), the size of microparticles decreased (from $48.02{\mu}m$ to $10.63{\mu}m$) and more uniform size distribution was noticeable due to the powerful emulsifying ability of PVA. A higher drug loading (from 5% to 20%) caused a larger concentration gradient between 2 phases at the polymer precipitation step; this resulted in decreased encapsulation efficiency (from 34.19% to 25.67%) and a greater initial burst (from 61.71% to 70.05%). SKL-2020-loaded PLGA microparticles prepared with different fabrication conditions exhibited unique release patterns of SKL-2020. High PVA concentration and high drug loading led to an initial burst effect by rapid drug diffusion through the polymer matrix. Since PLGA microparticles enabled the slow release of SKL-2020 over 1 week in vitro and in vivo, more convenient and comfortable treatment could be facilitated with less frequent administration. It is feasible to design a release profile by mixing microparticles that were prepared with different fabrication conditions. By this method, the initial burst could be repressed properly and drug release rate could decrease.

Development of a Model for Identifying Drug Organizations and Their Scale through Tweet Clustering

  • Jin-Gyeong Kim;Eun-Young Park;Da–Sol Kim;Cho-Won Kim;Jiyeon Kim
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.10
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    • pp.207-218
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    • 2024
  • In this paper, we propose a model for identifying drug trafficking organizations and assessing their scale by collecting drug promotional tweets from the social media platform 'X,' with a focus on investigating drug crimes that frequently occur among teenagers and young adults. Recently, various cyber crimes, such as drug distribution, illegal gambling, and sex offense, have been on the rise, exploiting the anonymity provided by social media. Drug trafficking organizations, in particular, operate in a decentralized cell structure, where each member receives anonymous instructions regarding only their specific role and is not directly connected to other members. To track these types of crimes, we designed experimental scenarios using various clustering algorithms, such as K-means Clustering and Spectral Clustering, alongside text embedding models like BERT (Bidirectional Encoder Representations from Transformers) and GloVe (Global Vectors for Word Representation). Furthermore, the clustering results derived from each scenario are validated using Jaccard Similarity and a full-scale investigation. We then analyze tweet clusters identified as the same drug organization across all scenarios, prioritizing the identification of high-priority accounts for cyber investigations.

Liver Targetability and Pharmacokinetics of $[^3H]$-Methotrexate-Lactosaminated Bovine Serum Albumin Conjugates ($[^3H]$-메토트렉세이트-락토오스아미노화한 소 혈청 알부민 공유결합체의 간표적성 및 체내동태)

  • Kim, Chong-Kook;Lee, Woong-Doo;Park, Ho-Koon
    • YAKHAK HOEJI
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    • v.36 no.6
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    • pp.591-597
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    • 1992
  • The organ distribution of $[^3H]$-methotrexate-lactosaminated bovine serum albumin conjugates ($[^3H]$-MTX-LBSA) was investigated to examine their role as a liver-specific anticancer drug. Synthesis of lactosaminated bovine serum albumin(LBSA) with BSA, lactose and sodium cyanoborohydride through reductive amination was followed by its conjugation with methotrexate (MTX) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), thereby synthesizing [$[^3H]$-MTX-LBSA conjugates. Organ distribution and plasma elimination profiles were studied in male Wistar rats after intravenous injection of [$[^3H]$-MTX-LBSA conjugates. The fates of $[^3H]$-MTX and the $[^3H]$-MTX-BSA conjugates´fates were also investigated for comparison. The results showed that the plasma level of $[^3H]$-MTX-LBSA conjugates declined more rapidly than those of $[^3H]$-MTX-BSA and their liver concentration was significantly higher than those of other treatment (p<0.01). In addition, their uptake compared to the amount taken up by the liver (1 : 33.1 at 10 min, 1 : 24.1 at 120 min). All these suggested that MTX-LBSA conjugate is one of the drug delivery system (DDS) that is advanced in concentrating MTX in the liver and minimizing the renal toxicity of MTX.

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Distribution and Drug Resistance of Salmonella Causing Enteric Fever in Taegu Area of Korea (대구지방에서의 장열성 Salmonella의 분포와 항균제내성)

  • Park, Jong-Wook;Suh, Seong-Il;Chun, Do-Ki
    • The Journal of the Korean Society for Microbiology
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    • v.22 no.3
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    • pp.295-300
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    • 1987
  • Salmonella strains isolated from blood in the Dong-san hospital, Taegu during the period from 1971 to 1986 were studied for species distribution, drug resistance, and R plasmids. The number of strains was 2,527 and all of them were classified into S. typhi and S. paratyphi A. Approximately 300 strains were isolated in the period from 1974 to 1976 and 1978, 268 in 1982, and 204 in 1983, but the numbers isolated in the 1980's have a tendency to decrease as compared with those of the 1970's. S. typhi occupied 85% or more of strains isolated until 1976, but the isolation frequency decreased yearly with some variation, and S. paratyphi A increased gradually from 1974. Only 4 strains of S. paratyphi A were resistant to some drugs, and the resistance was not transferred to E. coli by conjugation. S. typhi resistant to drugs were 15 in 1971 through 1973, 24 in 1974, and 13 in 1975, but afterwards only few resistant strains were isolated. These strains were resistant to two or more drugs; chloramphenicol(Cm), tetracycline(Tc), streptomycin(Sm), sulfisomidine(Su), ampicillin(Ap), and kanamycin(Km) and no strain resistant to other drugs tested was found. Strains resistant to 3 or less drugs didn't transfer the resistance to E. coli by conjugation. There were 15 strains resistant to four or more drugs, and were isolated in years from 1972 to 1976. These strains transferred the resistance to E. coli, and the resistance was considered to be mediated by R plasmids. Transfer frequency was higher at $25^{\circ}C$ than at $37^{\circ}C$ and patterns of transferred resistance were Cm, Tc, Sm, Su; Ap, Km; Cm. R plasmids having markers of Cm, Tc, Sm and Su were classified into Inc H1.

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Preparation and Characterization of a Propofol-loaded Polymeric Micellar System: Nanoparticular Stability

  • Cho, Jae-Pyoung;Cho, Jin-Cheol;Oh, Eui-Chaul
    • Journal of Pharmaceutical Investigation
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    • v.38 no.6
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    • pp.393-398
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    • 2008
  • A propofol delivery system was prepared using two biocompatible polymeric surfactants, poloxamer 407 and PEG 400. The nanoparticular stability of the micellar system was evaluated in terms of temperature change, storage time and composition. The particle size of the system was slightly increased with elevating temperature from $4^{\circ}C$ to $25^{\circ}C$, but its distribution was unimodal. At $40^{\circ}C$, the system presented a bimodal particle size distribution and the increase in the fraction of particles larger than 15 nm. This result might be due to the expansion of the nanoparticles through micellar swelling at the high temperature. It was found that propofol was gradually come out of the system, stored for a month at three different temperatures (4, 25 and $40^{\circ}C$). The drug loss was apparently dependent on temperature and the system composition. Increasing temperature induced the acceleration of the drug loss of $7{\sim}10%$ at $4^{\circ}C$ and $14{\sim}16 %$ at $40^{\circ}C$. This may be owing to the high diffusivity resulting from the swelling of the hydrophilic surface of the nanoparticle at high temperature. However, the addition of PEG 400 to the system led to the reduction of the drug loss. This result is associated with the previous investigation that PEG coverage decreased diffusion coefficient because of the formation of the denser structure on the surface of nanoparticulate. Nevertheless, the limited amount of PEG, less than 2% (w/v), should be used to prevent the precipitation and discoloration of the system.

A Study on Sickness and Utilization of Medical Care in a Rural Area of Kyunggido (일부(一部) 농어촌주민(農漁村住民)의 상병(傷病) 및 의료이용도(醫療利用度)에 관(關)한 조사연구(調査硏究))

  • Chang, Yong-Tae
    • Journal of Preventive Medicine and Public Health
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    • v.9 no.1
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    • pp.139-146
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    • 1976
  • This survey attempted to determine the overall health situation in Kyunggido in terms of sickness prevalence, sickness distribution, demand for medical care by type, and utilization of medical care. The survey was conducted on 766 households, or 4,065 people, from July 1-31, 1975. The findings from the survey are as follows: 1) In terms of age distribution, 28.7% of the sample was from 10-19, the 40-49 age group was the next largest group, and those over 60 made up 7% of the sample. 2. The education distribution is as follows, 30.4% completed primary school, 22.4% had no formal education, 20.6% attended but did not onplete primary school, and 1.8% attended unversities or higher. 3) In terms of occupation, 55.9% were unemployed or family employees, which represents a large dependent population, 30.4% of the workers were employed in farming or fisheries. 4. The marital status is as follows, 58.8% of the women were married, 32.3% unmarried, and 7.5% divorced. 5) The prevalence rate of mouthy illness was 19.7% of 100 infant, 42.8% became fatally ill within the first year of life. This is a very high percentage compared with more developed nations. 6) Of those reportion on illness, 54.6% sought treatment. The rate of treatment was highest in infants at 77.7%. Us age increased, demand for treatment decreased to 43.1% for those in the aldest age group. The oldest age group also had the highest rate of non treatment at 56.8%. 7) The demand for medical care showed that 65.6% utilized drug stores, 20.2% utilized hospitals and clinics, 5.4% used herbdrug-stores and herb clinices, and 3.9% relied upon folk medicine and withch craft. 8) The utilization of medical facilties by sex is as follows, 65.1% of the men and 66.0% of the women used drug stores, and 19.2% of the men and 20.2% of the women used hospitals and clinics. However, more men (3.5%) were hospitalized than women (1.8%) 9) In terms of out-patient care, the largest age group of males was 10-19 (28.2%), and the largest age group of females was 0-9 (30.8%). There was no sex difference in the use of western pharmacies. Menaged 30-39 and women aged 50-59 were the most frequent users of herb clinics. 10) The rate of receiving treatment at drugstore hospitals went towards declining level in the second case of what While increaing much more at herb clinics and folk medicines in the second case than the first one. 11) After primary utilization of hospitals, 32.7%. of the adults aged 20-59 used drug-stores as a secondary source of care, and 12.8% of children and youth under age 20 continued receiving care at hospitals. 12) After primary utilization of drug-stores, 32.5 % of the adults continued to seek care at drug stores and 1.8% used hospitals. 4.2% of those over age 60 utilized folk medcine and witch craft.

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Development of Classification Model for hERG Ion Channel Inhibitors Using SVM Method (SVM 방법을 이용한 hERG 이온 채널 저해제 예측모델 개발)

  • Gang, Sin-Moon;Kim, Han-Jo;Oh, Won-Seok;Kim, Sun-Young;No, Kyoung-Tai;Nam, Ky-Youb
    • Journal of the Korean Chemical Society
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    • v.53 no.6
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    • pp.653-662
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    • 2009
  • Developing effective tools for predicting absorption, distribution, metabolism, excretion properties and toxicity (ADME/T) of new chemical entities in the early stage of drug design is one of the most important tasks in drug discovery and development today. As one of these attempts, support vector machines (SVM) has recently been exploited for the prediction of ADME/T related properties. However, two problems in SVM modeling, i.e. feature selection and parameters setting, are still far from solved. The two problems have been shown to be crucial to the efficiency and accuracy of SVM classification. In particular, the feature selection and optimal SVM parameters setting influence each other, which indicates that they should be dealt with simultaneously. In this account, we present an integrated practical solution, in which genetic-based algorithm (GA) is used for feature selection and grid search (GS) method for parameters optimization. hERG ion-channel inhibitor classification models of ADME/T related properties has been built for assessing and testing the proposed GA-GS-SVM. We generated 6 different models that are 3 different single models and 3 different ensemble models using training set - 1891 compounds and validated with external test set - 175 compounds. We compared single model with ensemble model to solve data imbalance problems. It was able to improve accuracy of prediction to use ensemble model.

A Tracking Method of Same Drug Sales Accounts through Similarity Analysis of Instagram Profiles and Posts

  • Eun-Young Park;Jiyeon Kim;Chang-Hoon Kim
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.2
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    • pp.109-118
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    • 2024
  • With the increasing number of social media users worldwide, cases of social media being abused to perpetrate various crimes are increasing. Specifically, drug distribution through social media is emerging as a serious social problem. Using social media channels, the curiosity of teenagers regarding drugs is stimulated through clever marketing. Further, social media easily facilitates drug purchases due to the high accessibility of drug sellers and consumers. Among various social media platforms, we focused on Instagram, which is the most used social media platform by young adults aged 19 to 24 years in South Korea. We collected four types of information, including profile photos, introductions, posts in the form of images, and posts in the form of texts on Instagram; then, we analyzed the similarity among each type of collected information. The profile photos and posts in the form of image were analyzed for similarity based on the SSIM(Structural Simplicity Index Measure), while introductions and posts in the form of text were analyzed for similarity using Jaccard and Cosine similarity techniques. Through the similarity analysis, the similarity among various accounts for each collected information type was measured, and accounts with similarity above the significance level were determined as the same drug sales account. By performing logistic regression analysis on the aforementioned information types, we confirmed that except posts in image form, profile photos, introductions, and posts in the text form were valid information for tracking the same drug sales account.