Lipoproteins are biological lipids carriers. The natural and reconstituted lipoprotein based drug delivery systems have been extensively developed in recent years. This article reviews the development of natural and reconstituted low-density lipoprotein and high-density lipoprotein based vehicles in the antitumor area.
Animals ; Antineoplastic Agents ; administration & dosage ; chemistry ; Apolipoproteins B ; administration & dosage ; chemistry ; Drug Carriers ; administration & dosage ; chemistry ; Humans ; Lipoproteins ; administration & dosage ; chemistry ; Lipoproteins, HDL ; administration & dosage ; chemistry ; Lipoproteins, LDL ; administration & dosage ; chemistry ; Nanoparticles ; Neoplasms ; drug therapy ; Peptides ; administration & dosage ; chemistry ; Pharmaceutical Vehicles ; chemistry

Prodrug is an effective way to improve the oral absorption of the drugs which belong to Biopharmaceuticals Classification System (BCS) class III and IV. This review addresses the progress of the oral prodrugs in recent years, mainly including classical prodrug design and targeted prodrug design. Classical prodrug design is focused on modification of oil-water partition coefficient or decrease the metabolism of parent drugs. Targeted prodrug design is actively concerned with the physiological characteristics of the gastrointestinal tract to target tissues, enzymes and influx transporters. Intestinal influx transporter, the peptide transporter-targeted prodrug design is a growing field of the research of oral prodrugs recently. Challenges of prodrug strategy, design and investigation in vivo are also discussed.
Administration, Oral ; Animals ; Biological Transport ; Drug Delivery Systems ; Drug Design ; Humans ; Intestinal Absorption ; Prodrugs ; administration & dosage ; pharmacokinetics ; Solubility

To explore the mechanism of the absorption enhancement of borneol, the effect of borneol on the intestinal absorption and the pharmacokinetics of tetramethylpyrazine phosphate after oral administration were investigated. In situ intestinal recirculation was performed to study the effect of various concentrations of borneol on the absorption of tetramethylpyrazine phosphate at duodenum, jejunum, ileum and colon. After oral administration of tetramethylpyrazine phosphate, the mixture of tetramethylpyrazine phosphate and borneol and the mixture of tetramethylpyrazine phosphate and verapamil in rats, the concentrations of tetramethylpyrazine phosphate in plasma were determined by RP-HPLC at predesigned time. The pharmacokinetic parameters were compared based on the results of the three animal experiments, and analyzed with software program 3p97. The result showed that tetramethylpyrazine phosphate could be absorbed at all of the four intestinal segments with increasing absorption amount per unit as follows: colon > duodenum > jejunum > ileum, but without saturation, which demonstrated that tetramethylpyrazine phosphate was absorbed via simple diffusion. Borneol could enhance the intestinal absorption of tetramethylpyrazine phosphate, however, not in proportion. There was no obvious difference between the test group and the control group when 10 microg x mL(-1) borneol was added (P > 0.05), while when the concentration comes to 25 microg x mL(-1) and 50 microg x mL(-1), significant differences were observed (P < 0.05). Borneol and verapamil did enhance the bioavailability of tetramethylpyrazine phosphate after oral administration in rats. The enhancing effect of borneol showed only when the concentration came to a certain level but with no specific sites existed in the intestine. One of the mechanisms of borneol on the enhancing effect on absorption of tetramethylpyrazine phosphate might be the inhibition of the metabolism of CYP 3A and exocytosis of P-gp.
Animals ; Biological Availability ; Bornanes ; pharmacokinetics ; Herb-Drug Interactions ; Intestinal Absorption ; drug effects ; Male ; Pyrazines ; pharmacokinetics ; Rats ; Rats, Sprague-Dawley

This study is to prepare the microemulsion-based gel based on the W/O microemulsion and fluorouracil (5-Fu) as a model drug to study the transdermal characterization and observe its skin irritation of the microemulsion-based gel in vitro. IPM acted as oil phase, AOT as surfactant, Tween 85 as cosurfactant, water was added dropwise to the oil phase to prepare W/O microemulsion at room temperature using magnetic stirring, then 5-Fu powder was added. The gelatin was used as substrate to prepare 5-Fu microemulsion-based gel. The permeation flux of 5-Fu from 5-Fu microemulsion-based gel across excised mice skin was determined in vitro using Franz diffusion cell to study the influence of the amount of gelatin and the drug loading capacity. Refer to 5-Fu cream, the irritation of microemulsion and microemulsion-based gel on the rat skin was studied. Based on the water/AOT/Tween 85/IPM microemulsion, only the gelatin can form the microemulsion-based gel. At 25 degrees C, 32 degrees C and 40 degrees C, the amount of gelatin required for the formation of microemulsion-based gel were 7%, 14% and more than 17%, respectively. The 12 h transdermal cumulated permeation amount of 5-Fu from microemulsion-based gel containing 14% gelatin and 0.5% drug loading were (876.5 +/- 29.1) microg x cm(-2), 12.3 folds and 4.5 folds more than 0.5% 5-Fu aqueous solution and 2.5% (w/w) 5-Fu cream, respectively. Microemulsion-based gel exhibited some irritation, but could be subsided after drug withdrawal. Microemulsion-based gel may be a promising vehicle for transdermal delivery of 5-Fu and other hydrophilic drug.
Administration, Cutaneous ; Animals ; Antimetabolites, Antineoplastic ; administration & dosage ; adverse effects ; pharmacokinetics ; Dioctyl Sulfosuccinic Acid ; Drug Carriers ; Drug Delivery Systems ; Emulsions ; Exanthema ; chemically induced ; Fluorouracil ; administration & dosage ; adverse effects ; pharmacokinetics ; Gelatin ; chemistry ; Male ; Mice ; Myristates ; chemistry ; Polysorbates ; chemistry ; Skin ; pathology ; Skin Absorption ; Succinates ; chemistry ; Surface-Active Agents ; Viscosity

AIMTo prepare silybin-phospholipid complex and study its physicochemical properties. To compare the pharmacokinetic characteristics and bioavailability after oral administration of silybinphospholipid complex and silybin material in rats.

METHODSUsing acetone as a reaction medium, silybin and phospholipid were resolved into the medium, when the organic solvent was clear, then removed under vacuum evaporation, silybin-phospholipid complex was obtained. The new complex' s physicochemical properties including DSC, UV, IR were determined. The concentrations of non-conjugated and total silybin after oral administration of silybin-phospholipid complex and silybin material at different time in rats were determined by RP-HPLC. The pharmacokinetic parameters were computed by software program 3P97.

RESULTSExperiment results showed that silybin and phospholipid in the silybin-phospholipid complex were combined by non-covalent-bond, not forming a new compound and the solubility of silybin-phospholipid complex in water and n-octanol was effectively enhanced. It was found that mean plasma concentration-time curve of silybin after oral administration of silybin-phospholipid complex in rats was in accordance with one-compartment model with first-order absorption. Pharmacokinetic parameters of non-conjugated and total silybin in rats were respectively T(max) 10 min and 2 h; C(max) 0.11 and 1.08 microg x mL(-1); T1/2 2.18 and 3.84 h; AUC(0-infinity) 1.71 and 12.94 microg x mL(-1) x h. However, after oral administration of silybin material, plasma levels of both non-conjugated and total silybin were within the analytical detection limit.

CONCLUSIONIt was concluded that after oral administration of silybin-phospholipid complex in rats the bioavailability of silybin increased greatly. This was mainly due to an obvious improvement of the lipophilic property of silybin-phospholipid complex compared with silybin material and an increase in gastrointestinal absorption.

Administration, Oral ; Animals ; Area Under Curve ; Biological Availability ; Drug Compounding ; Male ; Phospholipids ; administration & dosage ; blood ; pharmacokinetics ; Rats ; Rats, Sprague-Dawley ; Silymarin ; administration & dosage ; blood ; pharmacokinetics ; Solubility

This study is to prepare the W/O microemulsion containing NaCl and fluorouracil (5-Fu) as a model drug to investigate the transdermal characteristics and skin irritation of the microemulsion in vitro. Isopropylmyristate (IPM) acting as oil phase, Aerosol-OT (AOT) as surfactant, Tween 85 as cosurfactant, NaCl solution was added dropwise to the oil phase to prepare W/O microemulsion at room temperature using magnetic stirring, and then 5-Fu powder was added. According to the area of microemulsion based on the pseudo-tertiary phase diagrams, the optimum formulation was screened initially. And the permeation flux of fluorouracil across excised mice skin was determined in vitro using Franz diffusion cells to study the influence of the amount of water and the drug loading capacity and optimize the formulation further. Refer to 5-Fu cream, the irritation of microemulsion on the rat skin was studied. The optimum formulation was composed of 0.7% (w/v) 5-Fu, 50% NaCl solution (0.05 mol x L(-1)), 20% mix-surfactant (AOT/Tween 85, K(m) = 2) and 29.3% oil (IPM). The cumulative amount of fluorouracil permeated in 12 h was (2 013.4 +/- 41.6) microg x cm(-2), 20.23 folds and 10.38 folds more than 0.7% fluorouracil aqueous solution and 2.5% (w/w) fluorouracil cream, respectively. Microemulsion exhibited some irritation, but could be reversed after drug withdrawal. The addition of NaCl significantly increased the content of water and the drug loading in microemulsion systems. The NaCl/AOT-Tween 85/IPM microemulsion system promoted the permeation of fluorouracil greatly, which may be a promising vehicle for the transdermal delivery of fluorouracil and other hydrophilic drug.
Administration, Cutaneous ; Animals ; Antimetabolites, Antineoplastic ; administration & dosage ; adverse effects ; pharmacokinetics ; Dioctyl Sulfosuccinic Acid ; chemistry ; Drug Carriers ; Drug Delivery Systems ; Emulsions ; Exanthema ; chemically induced ; Fluorouracil ; administration & dosage ; adverse effects ; pharmacokinetics ; In Vitro Techniques ; Male ; Mice ; Myristates ; chemistry ; Oils ; chemistry ; Polysorbates ; chemistry ; Rats ; Rats, Sprague-Dawley ; Skin Absorption ; Sodium Chloride ; chemistry ; Surface-Active Agents ; chemistry ; Water

AIMTo study the preparation of silymarin proliposomes. To study its physicochemic properties, its pharmacokinetical characteristics and bioavailability in rats after oral administration.

METHODSSilymarin proliposomes were prepared by film-deposition on carriers. When the proliposomes were contacted with water to form liposome suspensions, the tests of physicochemical properties including encapsulation efficiency, particle size and stability of the formed liposome suspensions were determined by HPLC, laser-particle-sizer and etc. The concentrations of non-conjugated and overall silymarin in plasma of rats and their pharmacokinetic behaviors after oral administration were studied by RP-HPLC. The pharmacokinetic parameters were computed by software program 3P97.

RESULTSThe encapsulation efficiency of silymarin liposomes could be more than 90%, with an average particle size of about 238.8 nm and a very good stability. The high bioavailability of silymarin proliposomes could be gotten by oral administration.

CONCLUSIONCompared with silymarin, silymarin proliposome is a stable and easily industrialized preparation and did enchance the gastrointestinal absorption of silymarin.

Administration, Oral ; Animals ; Area Under Curve ; Biological Availability ; Drug Carriers ; Drug Stability ; Liposomes ; Male ; Milk Thistle ; chemistry ; Particle Size ; Plants, Medicinal ; chemistry ; Rats ; Rats, Sprague-Dawley ; Silymarin ; administration & dosage ; blood ; chemistry ; pharmacokinetics ; Technology, Pharmaceutical ; methods

AIMTo investigate the in vitro and in vivo stability of 9-nitrocamptothecin lactone form in rat plasma.

METHODSThe specific and accurate HPLC method was developed for quantifying 9-nitrocamptothecin lactone form and the total lactone and carboxylate forms simultaneously. By using of this method, the ratios of lactone form to the total in rat plasma at different time were determined in vitro and in vivo. The results were compared to determine which was the main factor influencing the stability of 9-nitrocamptothecin lactone form in rat plasma in vivo.

RESULTSThe stability of lactone form in rat plasma was much higher in vivo than that in vitro.

CONCLUSIONBlood cells help to increase the stability of 9-nitrocamptothecin lactone form. Clearance from blood in vivo is the primary factor which influences the plasma stability of 9-nitrocamptothecin lactone form. The kinetic process of 9-nitrocamptothecin lactone form and total drug in rats were both best fitted to a two-compartment model. However, the process of 9-nitrocamptothecin carboxylate form in vivo was best fitted to a one-compartment model.

Animals ; Antineoplastic Agents ; blood ; pharmacokinetics ; Area Under Curve ; Camptothecin ; analogs & derivatives ; blood ; pharmacokinetics ; Carboxylic Acids ; blood ; pharmacokinetics ; Chromatography, High Pressure Liquid ; methods ; Drug Stability ; Lactones ; blood ; pharmacokinetics ; Male ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the procedure and the value of G-banding, fluorescence in sit hybridization (FISH) and comparative genomic hybridization (CGH) techniques in prenatal diagnosis.

METHODSKaryotype analyses with three diagnostic procedures, G-banding, G-banding and FISH, G-banding, FISH and CGH, were performed in the amniotic fluid samples taken from 102 fetuses at gestational ages 16-24 weeks. And the significance was valued in prenatal diagnosis.

RESULTSIn the first procedure of karyotype analysis, 98 cases were diagnosed, 2 cases were not conformed while 2 cases were failed in all 102 cases. In the second procedure, 2 cases were determined, 1 case was not conformed and 1 case was still failed. In the third step, 2 cases were diagnosed. The diagnostic rate of the karyotype reached to 100% (102/102 cases) using all the three procedures. In total, seven cases with chromosomal abnormality were diagnosed. Four cases, 1 case and 2 cases were identified in the first step (4/7, 57.1%), the second (1/7, 14.3%) and the third (2/7, 28.5%), respectively.

CONCLUSIONIt can help improve the diagnostic rate of chromosomal aberrations and standardize diagnostic procedure to perform the three detecting steps in prenatal diagnosis.

Chromosome Aberrations ; statistics & numerical data ; Chromosome Banding ; methods ; Chromosome Disorders ; diagnosis ; genetics ; Chromosomes, Human, Pair 18 ; Comparative Genomic Hybridization ; methods ; Female ; Fetus ; Gestational Age ; Humans ; In Situ Hybridization, Fluorescence ; Intellectual Disability ; genetics ; Karyotyping ; methods ; Male ; Nucleic Acid Hybridization ; methods ; Pregnancy ; Prenatal Diagnosis ; statistics & numerical data ; Risk Factors ; Ultrasonography, Prenatal ; methods

OBJECTIVE: To explore the value of ultrasonographic evaluation in fetal deformity in prenatal diagnosis by a systematic continuous sequence approach (SCSA). METHODS: Successive prenatal ultrasonographic evaluation was performed to monitor the whole anatomic structure,form, posture and movement of 16,685 fetuses during gestation aging 14 approximately 40(+3) weeks. RESULTS: Satisfactory ultrasonic images were obtained in 16,627 fetuses using the SCSA (99.65%). Of them, 514 abnormal fetuses were confirmed after subsequent labor or induced labor and 498 abnormal fetuses were correctly diagnosed using SCSA during prenatal stage (96.89%). Whereas 16 fetuses missed recognition (3.11%). Its sensitivity, specificity, positive and negative predictive value of diagnosis on fetal deformity were 96.98%, 99.96%, 98.66%, and 99.90 %, respectively. CONCLUSION SCSA in prenatal ultrasonographic evaluation of the fetal structure and malformation is reliable and accurate.
Adult ; Congenital Abnormalities ; diagnostic imaging ; Female ; Humans ; Pregnancy ; Sensitivity and Specificity ; Ultrasonography, Prenatal ; methods