Determination of Serum Concentration of Vitamin A in Healthy Volunteers and Hepatocirrhosis Patients by HPLC / 中国药房

OBJECTIVE:To establish a method for the concentration determination of vitamin A(VitA)in human serum,and apply it in healthy volunteers and hepatocirrhosis patients. METHODS:After liquid-liquid extraction,serum sample was deter-mined by HPLC. Using VitA acetic ester as internal standard,the separation was performed on Kromasil C18 column with mobile phase consisted of methanol-water (98∶2,V/V) at the flow rate of 1 ml/min. The wavelength was set at 325 nm,and the column temperature was room temperature. The sample size was 20 μl. RESULTS:The linear range of VitA were 0.012 4-3.210 μg/ml(r=0.997 2,n=5),and the limit of quantification was 0.012 4 μg/ml. Inter-day and intra-day RSD ranged 1.66%-2.97%;sample re-coveries were 98.18%-99.56%;extraction recoveries were 89.59%-91.38%. Average blood concentration of VitA were(0.71±0.08)μg/ml in 24 healthy volunteers and (0.28 ± 0.06)μg/ml in 24 hepatocirrhosis patients. There was statistical significance in average blood concentration of VitA between healthy volunteers and hepatocirrhosis patients in different age groups (P<0.05). CONCLU-SIONS:The method is simple,rapid,sensitive and accurate,and can be used for the concentration determination of VitA in serum of healthy volunteers and hepatocirrhosis patients.

Preparation and performance of three kinds of thermoresponsive acellular carriers / 中国组织工程研究

BACKGROUND:To design and fabricate a novel three-dimensional thermoresponsive polymer cel scaffold is one of the hot topics in the research of polymer science. OBJECTIVE: To prepare three different kinds of thermoresponsive acelular carriers and to evaluate their performance. METHODS:The copolymer N-isopropylacrylamide temperature acelular scaffold, macroporous copolymer N-isopropylacrylamide temperature acelular scaffold and macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive acelular scaffold were prepared. The specific surface area, thermoresponsive performance, porosity, pore size and biocompatibility of these three groups of scaffolds were determined. RESULTS AND CONCLUSION: The specific surface area of copolymer N-isopropylacrylamide thermoresponsive acelular scaffold, macroporous copolymer N-isopropylacrylamide thermoresponsive acelular scaffold and macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive celular scaffold was respectively 135, 386, 421 m2/g. The lower critical solution temperature was 30, 28.5, 29.5℃. The cel toxicity reaction was respectively grade 2, 2, 1. These indicators showed that the three kinds of scaffolds were provided with a temperature-sensitive characteristics and similar lower critical solution temperature. The biocompatibility of macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive acelular scaffold was significantly better than the other two scaffolds. The porosity and pore size of macroporous copolymer N-isopropylacrylamide thermoresponsive acelular scaffold and macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive acelular scaffold were greater than those of the copolymer N-isopropylacrylamide thermoresponsive acelular scaffold (P < 0.05). These results demonstrate that macroporous copolymer N-isopropylacrylamide thermoresponsive acelular scaffold and macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive acelular scaffold have more obvious pore structure.

Oxidized sodium alginate used in an extracorporeal circulation pipe / 中国组织工程研究

BACKGROUND:At present, a heparin-coated extracorporeal circulation pipe is used widely, but the price is expensive and limits its wide application. OBJECTIVE:To screen the optimal coating condition of oxidated sodium alginate as a coating material to coat the medical polyvinyl chloride pipe and to evaluate the anticoagulant properties and the stability of the coated pipe. METHODS:Oxidized sodium alginate was prepared with sodium periodate, and the mole ratio of sodium periodate and sodium alginate was 1:8, 1:10 and 1:12, respectively. Oxidized sodium alginate with different degree of oxidation was coated on the surface of medical polyvinyl chloride pipes by chemical methods, then to select the best degree of oxidation. The optimal coating condition was screened through an orthogonal experiment based on concentrations of sulfuric acid, polyethyleneimine and oxidized sodium alginate, and pH value and temperature of oxidized sodium alginate. Additional y, the anticoagulant properties and expulsion rates of the prepared pipes were evaluated in comparison with the blank control group and heparin-coated group. RESULTS AND CONCLUSION:The optimal oxidation degree for oxidized sodium alginate was 1:10 for the mole ratio of sodium periodate and sodium alginate. The best coating conditions were 50%concentrated sulfuric acid, 0.05%polyethyleneimine, 40 ℃ of reaction temperature, 2 g/L oxidized sodium alginate, and pH value=3.5. The oxidized sodium alginate coating group had a similar trend compared with heparin-coated group in the expulsion rate. The anticoagulant properties of oxidized sodium alginate coating group were little weaker than those of heparin-coated group (P<0.05), but significantly better than those of the blank control group. The oxidized sodium alginate-coated extracorporeal circulation pipe has a good anticoagulant property and stability.

Long-term anti-cancer implants inhibiting the activity of tumor growth in animal models / 生物医学工程学杂志

This study was aimed to establish rat bladder tumor animal models to investigate the in viva antitumor effect of polyanhydride-pirarubicin (PAD-THP), a long-lasting anti-cancer implant, in the bladder tumor of animal models. The model of bladder cancer was set up with N-butly-N-(4 hydroxybutyl) nitrosamine (BBN) feeding into rats. The PAD-THP long-acting anti-cancer implants containing the drugs and the same dose of the THP naked drug were placed under the bladder mucosa of bladder tumor model in vivo. The pirarubicin plasma concentration was measured with high performance liquid chromatography (HPLC) detection in vivo. The effective drug concentration and lasting period were observed and compared in the animal bodies. The tumor sizes were measured before and after the treatment. The in viva antitumor effects were analyzed and compared. The results showed that more significant antitumor effect of PAD-THP implants on the local drug release characteristics were presented compared with that of the same dose of THP bare drug group and there were significant differences (P<0. 05) between the two methods. All the results indicated that the PAD-THP anti-cancer implants in the postoperative local treatment of bladder tumors would show prosperous in the future for clinical application.

Aldehyde seaweed polysaccharide composites serve as artificial liver carriers / 中国组织工程研究

10.3969/j.issn.2095-4344.2013.25.014

Preparation and selection of a new sodium alginate-heparin composite coating with multi-aldehyde groups / 中国组织工程研究

10.3969/j.issn.2095-4344.2013.25.015

Study on modification and biocompatibility of coated medical polycarbonate / 国际生物医学工程杂志

Objective To prepare and evaluate the biocompatibility of polycarbonate coated with low molecular weight heparin (LMWH) and partial oxidation sodium alginate(OSA).Methods Coating material was prepared by means of chemical graft-modification and the feature of the material was determined with infrared spectrum and the stablity of the coating in fluid was examined.Biocompatibility was evaluated by contact angle and in-vitro tests including protein adhesion,platelet adhesion and caugulation.Results LMWH or OSA was tightly combined with polycarbonate.After being coated,the contact angle,albumin and fibrinogen adhering to materials were decrease (P＜0.05).The anticoagulant activity was notably promoted by coating.Compared with LMWH coated material,the contact angle,albumin and fibrinogen adhering were decreased significantly,but the improvement of anticaugulation was limited(P＜0.05).Conclusion Chemical graft-modification LMWH or OSA can be applied to polycarbonate.The biocompatibility of the coated materials was significantly promoted.

The study of absorbable sustained-release implants and animal experiments to prevent recurrence of bladder cancer / 生物医学工程学杂志

This paper aims to prepare polyanhydride-Pirarubicin dose long-acting sustained-release implants for the treatment of bladder cancer and for the prevention of postoperative recurrence of bladder cancer. Pirarubicin hydrochloride (THP) and polyanhydride, in accordance with a certain proportion, were fully mixed in the agate morta and dissolved in dichloromethane, and then were cast into a film within a mold put in the dryer set at 4 degrees C. Each tablet implanted contained 5.0 mg of THP. Polyanhydride-pirarubicin sustained-release was implanted into the bladder mucosa of the rabbits, and blood and urine samples were taken at different times after the operation. The THP drug concentrations in urine and blood were determined with high-performance liquid chromatography. The THP concentration in urine was significantly higher than the THP concentration in plasma. The drug concentration in urine reached (92.5 +/- 7.4) microg/L at 250 d time after the operation. Polyanhydride-pirarubicin implants possess long-acting sustained-release level dynamics in the body. It can maintain a stable long-term drug release and can be expected to last a year and can effectively prevent recurrence of bladder cancer. The present experiments proved that the implants with sustained-release drug treatment are expected to be useful in the clinical application in prevention of bladder cancer recurrence.

Investigation of polyanhydride-glucan as stem cell carriers / 生物医学工程学杂志

<p><b>UNLABELLED</b>The purpose of this study with regard to the effects of polyanhydride--three-dimensional vector-glucan material on the fetal liver stem cell adhesion and proliferation was to find a new carrier. The methods of two-step collagenase perfusion digestion and liquid Percoll discontinuous density gradient centrifugation were used for the separation of fetal liver stem cells. The fetal liver stem cells were selected and cultivated in the polyanhydride-three-dimensional vector-glucan material. Inverted microscope was used to observe cell adhesion and growth status. Also performed were: Calculation of the rate of cell adhesion; MTT assay of the cells in each group absorbance value (OD value); collecting and counting the cells on the carrier scaffold. Then the cell carriers histological sections (HE staining) were observed. On the 7th day of cell culture, the cells were subjected to immunofluorescence staining and flow cytometry.</p><p><b>RESULTS</b>polyanhydride-three-dimensional vector-glucan promoted liver stem cells growth and adhesion. There were active functions of the liver stem cells within carrier materials. In the three-dimensional surface and the internal culture of liver stem cell, proliferation was sustained. After 40 days, the polyanhydride co-culture-three-dimensional vector-glucan showed no sign of toxicity to stem cells. Human fetal liver stem cells attached to the polyanhydride--three-dimensional vector-glucan stent. The cell proliferation went on well and exhibited sustained expression of markers; 7 days training led up to an increase of 19.7 percent in the number of cells. Conclusively, polyanhydride-three-dimensional vector-glucan can be used for promoting the proliferation of liver stem cells, and liver stem cells can be used as vectors in liver tissue engineering.</p>

Growth activity of fetal liver stem cells in polyanhydride-three-dimensional vector-glucan / 中国组织工程研究

OBJECTIVE: To observe effects of polyanhydride-three-dimensional vector-glucan material on the fetal liver stem cell adhesion and proliferation.METHODS: The two-step collagenase perfusion digestion and bliquid percoll discontinuous density gradient centrifugation was used to isolate fetal liver stem cells. Fetal liver stem cells at the third passage were incubated on the polyanhydride-three-dimensional vector-glucan material. Inverted microscope was utilized to observe cell adhesion and growth status. Cell adherent rate, proliferation activity were calculated, and cell number was counted. Cell-vector was obtained for tissue section. Using hematoxylin-eosin staining, cell growth in the vector was observed under the optical microscope. At 7 days,immunofluorescence staining and flow cytometry were used to determine marker expression.RESULTS: Polyanhydride-three-dimensional vector-glucan promoted grow and adhesion of liver stem cells. There was the active function of the liver stem cells within carrier materials. In the three-dimensional surface and the internal culture, liver stem cell proliferation was sustained. After 10 days, the polyanhydride common culture-three-dimensional vector-glucan on stem cells was non-toxic, and human fetal liver stem cells could be attached to the polyanhydride-three-dimensional vector-glucan stent. The cell proliferation was better and dynamic sustained expression of markers. 7-days training received 19.7 percent increase in the number of cells.CONCLUSION: Polyanhydride-three-dimensional vector-glucan promotes the proliferation of liver stem cells, and liver stem cells can be used as the vector in liver tissue engineering.

Preparation of the EPC and HEPC sterically stabilized doxorubicin liposomes and further studies on pharmacokinetics in rats / 生物医学工程学杂志

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.

Synthesis of peptide fragment of melittin and the function of rheumatoid arthritis cure / 生物医学工程学杂志

To retain the anti-rheumatoid arthritis activity of melittin and to reduce the hemolysis and hypersusceptibility caused by melittin, a deletion peptide of melittin was synthesized. Its ant-inflammation effect was observed . A hydrophile peptide fragment of melittin was synthesized by standard solid-phase method. The product was analyzed by HPLC and MS. The relevant hemolysis and hypersusceptibility were tested. The rabbits' model of immune arthritis were established and treated. The results showed that the hemolysis rate for peptide fragment was less than 5%, the hypersusceptibility rate was less than 8%. The hydrophile peptide fragment of melittin may retain anti-rheumatoid arthritis activity and reduce the melittin-induced hemolysis and hypersusceptibility.

Quality Standard of Erkening Misture / 中国药房

OBJECTIVE: To establish the quality stangard of Erkening misture.METHODS:Raphanus sativus and Fritillaria thunbergii were identifided by TLC, and the content of the Baicalin in Erkening misture was determinated by HPLC. RESULTS: The TLC spots of Raphanus sativus and Fritillaria thunbergii were distinctive. The linear range of Baicalin was 0.319～2.64 ?g (r=0.999 3). The average recovery was 99.56%, and RSD was 0.83% (n=9). CONCLUSION: This established standard can be used for the quality control of the Erkening misture.

The synthesis of polyanhydrides and its application in biomedical field / 生物医学工程学杂志

This paper reviews the development of the polyanhydrides as a new biodegradable polymer, and highlights the methodological and technological progress in the synthesis of the polymer. Subsequently, the future researches and developments of polyanhydrides are prospected.