• 제목/요약/키워드: drug modification

검색결과 146건 처리시간 0.023초

Regioselective Enzymatic Acylation of Multi-hydroxyl Compounds in Organic Synthesis

  • Park, Hyun-Gyu;Do, Jin-Hwan;Chang, Ho-Nam
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제8권1호
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    • pp.1-8
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    • 2003
  • With current developments in enzyme-catalyzed reactions and techniques available for rational redesign of natural biocatalysts, the enzymatic biosynthesis can become one of the most valuable Synthetic methods. Enzymatic regioselective catalysis in organic media has played a key role in pursuing asymmetric synthesis for active chiral compounds. Here, we shortly do-scribe some historical issues of the rapidly growing area, enzymatic catalysis in synthetic organic chemistry and then review researches that have been carried out in the regioselective enzymatic catalysis for the past two decades. An application of this technology to the modification of some potential target drug co m pound will be adios presented.

Dynamically Modified Silica and its Applications in Drug Control and Drug Metabolism Studies

  • Hansen, Steen Honore;Helboe, Per;Thomsen, Morgens
    • 생약학회지
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    • 제19권4호
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    • pp.217-227
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    • 1988
  • An alternative to the well known reversed-phase separations on chemically-boned phases has been developed. The approach is based on a dynamic modification of bare silica with long chain quaternary ammonium ions. The influence of the concentration and type of quaternary ammonium ion, the pH value and the ionic strength of the eluent on the selectivity towards test solutes has been investigated. The large number of parameters that can be attained. Once established, a high degree of reproducibility of the selectivity between solutes is obtained even when using different brands of silica; this is in contrast to the situation when using chemically-bonded phases, such as for example, different brands of octadecylsilyl-bonded silica materials. Examples of the use of system in pharmaceutical analysis and drug metabolism studies are given.

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약물이상반응에 대한 응급구조학과 학생의 지식과 태도 조사 (Investigating attitudes and knowledge of paramedic students regarding adverse drug reactions)

  • 김사라;김철태
    • 한국응급구조학회지
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    • 제25권3호
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    • pp.93-109
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    • 2021
  • Purpose: This study aims to investigate the knowledge and attitudes regarding adverse drug reactions (ADR) of emergency medical services (EMS) students, so that suggestions for further education on ADR can be made. Methods: A survey on knowledge and attitude was created and modified according to Lee's and Kim's test tool. In total, 149 students' data were collected and compared with previous studies. Results: Knowledge of ADR was relatively low (54%) but attitude was relatively high (75%). Clinical experience was important in knowledge and attitude. Knowledge and attitude showed a positive correlation. Conclusion: Increased knowledge of ADR leads to a more active attitude towards it. Hence, modification of the education system to provide a more personalized education is required.

Doxorubicin-loaded PEI-silica Nanoparticles for Cancer Therapy

  • Heekyung Park;Seungho Baek;Donghyun Lee
    • Korean Chemical Engineering Research
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    • 제61권4호
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    • pp.570-575
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    • 2023
  • Targeted anticancer drug delivery systems are needed to enhance therapeutic efficacy by selectively delivering drugs to tumor cells while minimizing off-target effects, improving treatment outcomes and reducing toxicity. In this study, a silica-based nanocarrier capable of targeting drug delivery to cancer cells was developed. First, silica nanoparticles were synthesized by the Stöber method using the surfactant cetyltrimethylammonium bromide (CTAB). Increasing the ratio of EtOH in the solvent produced uniformly spherical silica nanoparticles. Washing the nanoparticles removed unreacted residues, resulting in a non-toxic carrier for drug delivery in cells. Upon surface modification, the pH-responsive polymer, polyethyleneimine (PEI) exhibited slow doxorubicin release at pH 7.4 and accelerated release at pH 5.5. By exploiting this feature, we developed a system capable of targeted drug release in the acidic tumor microenvironment.

노인의 약물 사용 실태 조사 (Drug Use in the Elderly)

  • 박미숙
    • 기본간호학회지
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    • 제15권2호
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    • pp.195-205
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    • 2008
  • Purpose: This study was conducted to identify drug use by elders. Method: There were 304 participants age 65 or older included in this study. Data were collected using a questionnaire about drug use in the past 4 weeks. The questionnaire, a modification of Uhm's (2005), Lee's (2001), and Ellor and Kurz's (1982) tools, consisted of 17 questions on general and health characteristics, 17 on drug usage and 9 on behaviors related to drug misuse. Results: 85.5% of participants reported laking at least one type of prescription or non-prescription drug. 26.0% of participants reported taking only prescription drugs, 3.9% reported taking only non-prescription drugs, and 55.6% reported taking both prescription and non-prescription drugs. 17.1% of participants reported side effects from the drugs. The mean score for behaviors related to drug misuse was 7.53. Elders taking only non-prescription drugs showed more drug misuse than elders taking only prescription drugs or both. Women used more prescription, non-prescription drugs or both than man. Elders in rural areas used more non-prescription drugs than those in urban areas. Conclusion: Even though pharmacies were separated from medical practices in 2000, most older adults continue to use and misuse prescription and non-prescription drugs.

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Intracellular Posttranslational Modification of Aspartyl Proteinase of Candida albicans and the Role of the Glycan Region of the Enzyme

  • 나병국;송철용
    • 미생물학회지
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    • 제38권4호
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    • pp.218-218
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    • 2002
  • Using two drugs, tunicamycin and brefeldin A, which affect protein processing, we investigated the intracellular processing mechanism of secreted aspartyl proteinase 1 (SAPl) of Candide albicans. Three intracellular forms of SAPI were detected by immunoblotting using menoclonal antibody (MAb) CAPl. Their molecular weights were approximately 40, 41 and 45 kDa, respectively. The 41 kDa protein is a glycoprotein and may be the same as the extracellular form judging by its molecular mass. The 40 kDa protein was the unglycosylated form and its molecular mass coincided with deglycosylated SAPl and the 45 kDa protein was also the unglycosylated form. Neither the 40 and 45 kDa proteins were detected in the culture supernatant of C. albicans. These suggested that the 40 and 45 kDa proteins might be intracellular precursor forms of SAPI. These results show that SAPI is translated as a 45 kDa precusor form in the endoplasmic reticulum and the 45 kDa precursor farm undergoes proteolytic cleavage after translocation into the Golgi apparatus, generating the 40 kDa precursor form. This 40 kDa precursor is converted into a 41 kDa mature form through glycosylation in the Golgi apparatus. The mature form of the 41 kDa protein is sorted into secretary vesicles and finally released into the extracellular space through membrane fusion. When the glycan region of SAPl was digested with N-glycosidase F, both stability and activity of the enzyme decreased. These results indicate that the glycan attached to the enzyme may, at least in parti be related to enzyme stability and activity.

Levan acetate를 이용한 hydrocortisone의 방출 제어

  • 임승;이기영;김동운;최춘순
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2001년도 추계학술발표대회
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    • pp.849-852
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    • 2001
  • The preparation, characterization and drug release behaviour of hydrocortisone(HC) loaded levan acetate microparticles were investigated. Hydrophobic levan acetate was prepared by chemical modification of hydrophilic levan and micro particles were made by dialysis method or solvent evaporation method. The morphology of levan acetate was observed by SEM and drug release profiles were investigated at pH 7.4 and pH 1.2. Newly synthesised levan acetate can be used for carrier of drugs.

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New Coating Method for Sustained Drug Release: Surface Modification of ePTFE Grafts by inner coating PLGA

  • Kim, Hyeseon;Park, Seohyeon;Kim, Dae Joong;Park, Jong-Sang
    • Bulletin of the Korean Chemical Society
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    • 제35권5호
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    • pp.1333-1336
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    • 2014
  • Expanded polytetrafluoroethylene (ePTFE) grafts have been used as vascular access for many patients suffering from end stage renal disease. However, the vascular graft can cause significant clinical problems such as stenosis or thrombosis. For this reason, many studies have been performed to make drug eluting graft, but initial burst is major problem in almost drug eluting systems. Therefore we used biodegradable polymer to reduce initial burst and make sustained drug delivery. The ePTFE grafts were dipped into a paclitaxel-dissolved solution and then PLGA-dissolved solution was passed through the lumen of ePTFE. We analyzed whether the dose of paclitaxel is enough and the loading amount of PLGA on ePTFE graft increases according to the coating solution's concentration. Scanning electron microscope (SEM) images of various concentration of PLGA showed that the porous surface of graft was more packed with PLGA by tetrahydrofuran solution dissolved PLGA. In addition, in vitro release profiles of Ptx-PLGA graft demonstrated that early burst was gradually decreased as increasing the concentration of PLGA. These results suggest that PLGA coating of Ptx loaded graft can retard drug release, it is useful tool to control drug release of medical devices.

Curcumin-Loaded PLGA Nanoparticles Coating onto Metal Stent by Electrophoretic Deposition Techniques

  • Nam, So-Hee;Nam, Hye-Yeong;Joo, Jae-Ryang;Baek, In-Su;Park, Jong-Sang
    • Bulletin of the Korean Chemical Society
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    • 제28권3호
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    • pp.397-402
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    • 2007
  • Restenosis after percutaneous coronary intervention (PCI) continues to be a serious problem in clinical cardiology. To solve this problem, drug eluting stents (DES) with antiproliferative agents have been developed. Variable local drug delivery systems in the context of stenting require the development of stent manufacture, drug pharmacology and coating technology. We have worked on a system that integrates electrophoretic deposition (EPD) technology with the polymeric nanoparticles in DES for local drug delivery and a controlled release system. The surface morphology and drug loading amount of DES by EPD have been investigated under different operational conditions, such as operation time, voltage and the composition of media. We prepared poly-D,L-lactide-co-glycolic acid (PLGA) nanoparticles embedded with curcumin, which was done by a modified spontaneous emulsification method and used polyacrylic acid (PAA) as a surfactant because its carboxylic group contribute negative charge to the surface of CPNPs (?53.5 ± 5.8 mV). In the process of ‘trial and error' endeavors, we found that it is easy to control the drug loading amount deposited onto the stent while keeping uniform surface morphology. Accordingly, stent coating by EPD has a wide application to the modification of DES using various kinds of nanoparticles and drugs.

탄닌산을 이용한 나노입자 표면 개질 및 분석 (Tannic acid Mediated Surface Modification of Mesoporous Silica Nanoparticles)

  • 이주연;김형준
    • 접착 및 계면
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    • 제23권3호
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    • pp.70-74
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    • 2022
  • 탄닌산은 식물 유래 폴리페놀 중 하나로, 대부분의 생체고분자와 분자간결합을 할 수 있어서 분자적 접착제로서 연구가 되어 왔으며, 표면 개질, 에너지 저장 및 발생 장치, 의료용 제재로서 활용이 되고 있다. 본 연구에서는 약물 전달과 바이오이미징 등 의생명공학 분야에서 다양하게 활용되는 다공성 실리카 나노입자를 합성하고, 탄닌산을 이용하여 다공성 실리카 나노입자의 표면을 개질 한 뒤, 나노입자의 표면을 분석하였다.