1.Antibiotic use at a pediatric age.
Yonsei Medical Journal 1998;39(6):595-603
For infections in infants and children, the successful antibiotic treatment depends primarily on rapid diagnosis of the disease, identification of pathogenic microorganisms, and appropriate application of specialized pharmacokinetic and pharmacodynamic knowledge of antibiotics in children. In infants and children, the absorption, distribution, metabolism, and excretion of drugs may differ considerably in comparison with adults. Because of known toxicity, certain drugs such as chloramphenicol in high doses, the sulfonamides, and tetracycline should not be used in neonates. In this article, we describe these peculiarities of children and discuss the proper use of antibiotics in children.
Antibiotics/therapeutic use*
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Antibiotics/pharmacokinetics
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Antibiotics/metabolism
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Antibiotics/administration & dosage
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Child, Preschool
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Dose-Response Relationship, Drug
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Human
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Infant
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Pediatrics/methods*
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Time Factors
2.A fiber optic chemical sensor system for on-line monitoring the drug dissolution of rifampicin.
Xin-xia LI ; Yu-wen WANG ; Yan WANG ; Jian CHEN
Acta Pharmaceutica Sinica 2002;37(9):721-723
AIMTo study a continuous, on-line and automatic monitoring method for dissolution of drugs.
METHODSA new fiber optical chemical sensor prepared by sol-gel immobilization of molecular probe was reported. Based on multiple quenching of flurescence, an instrument and software system was designed to on-line monitor the drug dissolution of rifampicin.
RESULTSThe concentration of rifampicin was linear with ln(F0/F) when concentration was in the range of 10-170 micrograms/mL-1. The relative coefficient was 0.9993. The procession of dissolution can be on-line monitored. Parameters were obtained directly from the dissolution curve. There is no distinctly difference when compared with the method of the Pharmacopoeia of People's Republic of China (P > 0.05).
CONCLUSIONThis procession analysis can reflect the real dissolution of drug and obtain the total information.
Antibiotics, Antitubercular ; administration & dosage ; chemistry ; Automatic Data Processing ; Capsules ; Rifampin ; administration & dosage ; chemistry ; Solubility
3.Preparation of Collagen Modified Hyaluronan Microparticles as Antibiotics Carrier.
Jong Eun LEE ; Jong Chul PARK ; Joong Gon KIM ; Hwal SUH
Yonsei Medical Journal 2001;42(3):291-298
Hyaluronan (HA), a natural glycoaminoglycan featuring an extracellular matrix, has been suggested as an effective biocompatible material. In this study, the effectiveness of HA microparticles as a carrier system for antibiotics was evaluated, and their physicochemical characteristics were determined. Microparticles were fabricated by the gelation of sulfadiazine (SD) loaded HA solution with calcium chloride through either a granulation (GR-microparticles) or encapsulation (EN-microparticles) process, and atelocollagen was incorporated into the microparticles as an additive in order to improve their physical properties. The characteristics of the microparticles were examined by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and swelling test. In vitro release experiments were performed for 7 days and the released amount of SD was determined using high-performance liquid chromatography (HPLC). Microscopic observations revealed that the collagen incorporated HA particles had a more compact surface than the HA particles. DSC analysis determined a loss of SD crystallinity in the particles. Calcium chloride retarded the swelling of particles, whereas the loaded drug contents did not affect this property. Both GR-and EN-microparticles sustained SD release with initial bursting effect. SD release from EN-microparticles was faster than from GR- microparticles. In addition, the release rate was dependent on the SD content in the microparticles. These results suggest that collagen modified HA microparticles have a potential as a release rate controlling material for crystalline drugs such as SD.
Antibiotics/*administration & dosage
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Calcium Chloride/pharmacology
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Collagen/*pharmacology
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*Drug Carriers
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Hyaluronic Acid/*administration & dosage
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Sulfadiazine/administration & dosage
4.Progress in electrochemotherapy.
Kong YANG ; Bisong YUE ; Zishu WANG
Journal of Biomedical Engineering 2004;21(6):1043-1046
Electrochemotherapy (ECT) is a novel cancer treatment in which electric pulses (EPs) inducing cell membrane pored (electroporation) are used as a means of delivering antitumor drugs to the cytoplasm of cancer cells. The minimal thresholds of electric field strength of in vitro tumor cell line and tumor tissue are 450-650 V/cm and 400-600 V/cm, respectively. The typical electrical requirement is 600-1300 V/cm, pulse width of 100 micros, 8 pulses, 1 Hz. More than 10 kinds of antitumor drugs have been applied to ECT, in which the most efficacious drug is Bleomycin, and then Cisplatin. Some exciting inhibitory effects on cells in vitro and on solid tumors in clinical trials have been noticed. The factors influencing ECT effects include the electric parameters, diameter of electrode, distribution of electric field lines, size of tumor, model of drugs injection and kinds of drugs. Some questions of ECT are still open, such as the dosages and kinds of drugs for clinical trials, model of drug injection, influence on normal tissues, therapeutic mechanism.
Antibiotics, Antineoplastic
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administration & dosage
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Antineoplastic Agents
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administration & dosage
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Bleomycin
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administration & dosage
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Cisplatin
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administration & dosage
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Electric Stimulation Therapy
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methods
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Electrochemistry
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Electroporation
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methods
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Humans
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Neoplasms
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therapy
5.Preparation and lymphatic targeting research of targeting antitumor drug: pectin-adriamycin conjugates.
Ming CHENG ; Ping XIE ; Xiaohai TANG ; Jie ZHANG ; Yongmei XIE ; Kaibo ZHENG ; Jun HE
Journal of Biomedical Engineering 2009;26(3):569-574
Pectin, a polysaccharide extracted from the cell wall of plants, was used as the drug carrier to synthesize the pectin-adriamycin conjugates (P(A)n). The structure of the conjugates was confirmed by UV and IR. The degree of esterification (DE) of the pectin was assessed, and it was found that DE significantly influenced the carboxy group contents, inherent viscosity and galacturonic acid contents of the pectin. The results of drug release test in vitro showed that the conjugate was stable in normal saline, but was gradually enzymolyzed to release the adriamycin in blood plasma and in lymph nodes. The results of lymphatic targeting study of P(A), demonstrated that the modification of DE or drug coupling capacity of pectin significantly influenced the lymphatic targeting characteristics of P (A)n. The adriamycin concentration of lymph nodes was 208 times higher than that of plasma after local injection of the P(A)n, of which the adriamycin content was 27.9% and the pectin was deesterificated 120 minutes by the use of hypothermy alkaline deesterification method.
Animals
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Antibiotics, Antineoplastic
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administration & dosage
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pharmacokinetics
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Doxorubicin
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administration & dosage
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pharmacokinetics
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Drug Carriers
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chemistry
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Esterification
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Lymph Nodes
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metabolism
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Pectins
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administration & dosage
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pharmacokinetics
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Rabbits
6.Preparation of the EPC and HEPC sterically stabilized doxorubicin liposomes and further studies on pharmacokinetics in rats.
Meili YU ; Yong WANG ; Guiming SHU ; Zhengyan ZHU ; Shuchang FANG ; Li WANG
Journal of Biomedical Engineering 2008;25(3):597-599
In this paper, we address the preparation of the EPC and HEPC sterically stabilized doxorubicin liposomes and report the data collected from further studies on pharmacokinetics in blood for choosing a better carrier in delivering the drugs. The pharmacokinetics of EPC and HEPC sterically stabilized liposomes (EPC-SSL, and HEPC-SSL) in Wistar rats were investigated by HPLC. The results showed that the mean residence time of HEPC-SSL in blood is 23.3 h, while that of EPC-SSL is 12.0 h. In conclusion, HEPC-SSL is a better carrier in delivering the drugs to the extravascular sites when compared with EPC-SSL.
Animals
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Antibiotics, Antineoplastic
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administration & dosage
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pharmacokinetics
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Delayed-Action Preparations
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chemical synthesis
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pharmacokinetics
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Doxorubicin
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administration & dosage
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pharmacokinetics
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Drug Carriers
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chemistry
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Hydrogenation
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Liposomes
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Phosphatidylcholines
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chemistry
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pharmacology
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Rats
7.Study on pharmaceutical characterization and pharmacokinetics of daunorubicin long-circulating liposomes in rat.
Hua ZHANG ; Xian-rong QI ; Qiang ZHANG
Acta Pharmaceutica Sinica 2002;37(4):299-303
AIMTo study the pharmaceutical characterization and pharmacokinetics of long-circulating liposomes containing daunorubicin.
METHODSThe morphology of daunorubicin long-circulating liposome was surveyed under the transmission electron microscope. The size of daunorubicin long-circulating liposomes was determined by laser scatter method. The entrapment efficiency and accelerative experiment stability of the daunorubicin long-circulating liposomes were examined. Visible spectrophotometry and the HPLC method were established for determination of the daunorubicin in the long-circulating liposomes. The percent release of daunorubicin from long-circulating liposomes in HBS (pH 7.5) and rat serum at 37 degrees C were examined. The pharmacokinetics in rats were studied.
RESULTSThe high entrapment efficiency (> 85%) and stabilized long-circulating liposomes could be achieved. The drug was slowly released from the daunorubicin long-circulating liposomes. The drug released from liposomes was less than 10% in 24 h. The T1/2 alpha and AUC of long-circulating liposome were higher than those in injections.
CONCLUSIONThe long-circulating liposomes prepared by us have high encapsulation efficiency and the pharmaceutical characterization showed good stability, they can be used for clinical purpose.
Animals ; Antibiotics, Antineoplastic ; administration & dosage ; pharmacokinetics ; Daunorubicin ; administration & dosage ; pharmacokinetics ; Delayed-Action Preparations ; Drug Carriers ; Liposomes ; Male ; Phosphatidylethanolamines ; Polyethylene Glycols ; chemistry ; Random Allocation ; Rats ; Rats, Wistar
8.Prolonged-releasing performance of drug loaded polyelectrolyte nanocapsules effected by acid phosphatease: in vitro analysis.
Lei JIANG ; Suyun CHEN ; Xiaoling YANG ; Jing YI ; Peiyong LI
Chinese Journal of Biotechnology 2008;24(10):1801-1807
The aims of the study were to prepare polyelectrolyte nanocapsules effected by acid phosphatease (ACP) and to study prolonged-releasing performance of the nanocapsules in vitro. Using the layer by layer (LbL) self-assembly technique, polyelectrolyte-beta-glycerophosphoric acid nanocapsules were prepared. The morphologies of the nanocapsules were characterized by transmission electron microscopy (TEM) and biocompatibility was well examined by cell-culture method. The drug adriamycin would be loaded in nanocapsules for concentration gradient, the encapsulation efficiency could be calculated. Nanocapsules were reacted with acid phosphatease standard and HepG2 cells that express the ACP, respectively. The prolonged-releasing of adriamycin was verified and tumor cells apoptosis were measured. TEM images showed that the nanocapsule sizes were between 200-300 nm. The material biocompatibility was good until the concentration of nanacapsule was up to 250 microg/mL. The drug encapsulation efficiency reached 68.12%. The release rate of polyelectrolyte (PAH/PSS-beta-glycerophosphoric acid)s nanocapsules was higher than in the control nanocapsules at 48 h (38% Vs 15%) after its reaction to the ACP standard (P < 0.05). Compared with the control, nanocapsules could significantly inhibit the growth of HepG2 cells that expressed the ACP, and the efficiency of cell apoptosis was 7.59% higher at 24 h (13.73 Vs 6.14, P < 0.05). Polyelectrolytes (PAH/PSS-beta-glycerophosphoric acid) nanocapsules in vitro have response to acid phosphatease by which prolonged-releasing can be affected. This property can be used for treatment of some malignant and benign diseases with elevated acid phosphatease level.
Acid Phosphatase
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pharmacology
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Antibiotics, Antineoplastic
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administration & dosage
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Delayed-Action Preparations
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chemical synthesis
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Doxorubicin
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administration & dosage
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Electrolytes
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chemistry
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Hep G2 Cells
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Humans
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Nanocapsules
9.Recent progress in application of local drug delivery for preventing restenosis after peripheral arterial revascularization.
Mingyi ZHANG ; Fuxian ZHANG ; Huan ZHANG ; Gangzhu LIANG
Chinese Journal of Surgery 2015;53(3):237-240
Restenosis following vascular revascularization remains an important clinical problem. Local drug delivery which can provide enough drug concentration in the lesion location without causing adverse systemic effect is an excellent solution for this question. We conducted a systematic literatory search on PubMed and CKNI through May 2014. After reviewing all related papers, we provided a comprehensive overview of the available drugs and techniques for local drug delivery that have been developed to prevent restenosis after peripheral vascular interventions, including innovations that have been tested only in animals as well as those already approved for clinical use. In brief, anti-proliferative drugs such as paclitaxel and sirolimus are the most used and suitable drugs for local delivery system. Additionally, some promising drugs including anti-inflammatory drugs, antioxidant drugs and drugs inhibiting cell proliferation and migration are already being tested in pre-clinical trials or animal models. At the same time, intraluminal and extraluminal delivery devices have also got a rapid development during the past decades. The efficacy of drug-eluting stent, drug-eluting balloon, porous and microporous balloon and the most recent drug-eluting bioresobable scaffold for preventing of restenosis in peripheral vessels have been demonstrated in humans or in animals, some of them even have received the CE mark in Europe. Endovascular microinfusion catheter and drug-loaded perivascular wraps have only been tested in animal models, more researches are needed. With the development of pharmacology and bioengineering, great strides will be made in the prevention of restenosis in the near future.
Animals
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Anti-Inflammatory Agents
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administration & dosage
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Antibiotics, Antineoplastic
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administration & dosage
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Arteries
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Coronary Restenosis
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prevention & control
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Drug Delivery Systems
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Drug-Eluting Stents
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Humans
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Myocardial Revascularization
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Paclitaxel
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Sirolimus