Biomedical subjects

Hong-tao Song

Publications and source records attributed to Hong-tao Song.

5 recordsLinked to original sources

PubMed2005

[Pharmacodynamics of compound danshen pH-dependent delayed release pellets in dogs].

AIM: To prepare the compound danshen pH-dependent delayed release pellets and filled them in capsules and then study thier pharmacodynamics. METHODS: The pH-dependent delayed release pellets were prepared by coating with HPMC, Eudragit L-30D-55 and Eudragit L100-Eudragit S100 (1:6), separately, and mixed in proper proportion to prepare the two pH-dependent delayed release systems T1 and T2. The release of delayed release pellets was determined according to the method of China Pharmacopoeia (2000) in the simulated gastrointestinal pH conditions. The pharmacodynamic,parameters were evaluated by serum pharmacology method. RESULTS: The compound danshen pH-dependent delayed release pellets were prepared with the characteristics of pH dependent delayed release profile in vitro. In single oral dose, the pharmacodynamic parameters of rapid release tablets R Emax (%) and Tmax (h) were 34.63% and 0.58 h, respectively. Tmax S of delayed-release pellets T1 and T2 were extended to 2.42, 3.17 h and Emax S (%) were declined to 13.57%, 14.52%. The relative bioavailabilities of T1 and T2 were 99.3%, 133.6% , respectively. In multiple oral doses of R the pharmacodynamic parameter of DF was 7.32 and those T1, T2 DF were 3.40, 3.03, respectively. CONCLUSION: The compound danshen pH-dependent delayed release capsules have characteristics of pH dependent releasing in vitro and characteristics of delayed release in vivo. In multiple oral (loses the DF of delayed release capsules was lower than that of rapid release tablet at steady state.

Animals↗

PubMed2004

[Diversity of invasiveness and matrix metalloproteinases expression profile of human gastric carcinoma xenografted in different tissue environments].

OBJECTIVE: To study the effect of tissue environment on the invasiveness of carcinoma cells and the implication of expression of matrix metalloproteinases. METHODS: Tissue from a human gastric carcinoma was transplanted and passaged subcutaneously in nude mice. After the 3rd passage, the xenografts were also transplanted into the abdominal cavity of nude mice. The invasiveness of xenografts at the two locations were observed morphologically and the expressions of MMP-2, MMP-7, MMP-9, MMP-13, TM1-MMP, TM2-MMP and TM3-MMP were monitored by immunohistochemistry. RESULTS: The subcutaneous xenografts of human gastric carcinoma in nude mice presented as expanding outgrowths with limited invasion. Except for MMP-7, the other 6 MMPs (MMP-2, MMP-9, MMP-13, TM1-MMP, TM2-MMP, TM3-MMP) were not expressed in the neoplastic cells nor in the tumor stroma. In contrast, the intra-peritoneal xenografts displayed an invasive growth pattern accompanied by more fibrous stroma. All MMPs examined were expressed in the tumor cells at the invasive fronts and in the adjacent stroma. CONCLUSIONS: Invasiveness and expression of MMPs were obviously diverse in human gastric carcinoma cells when grafted at different anatomic locations in nude mice, thus indicating: (1) There exists a close interaction between tumor cells and surrounding stromal cells. The tissue environment may play a definitive role in the tumor phenotype. (2) The expression of MMPs is closely related to the growth pattern and the invasiveness of tumor cells. MMPs produced by the stroma cells at the invasion front may be linked to the invasiveness of neoplastic cells.

Animals↗

PubMed2003

[Studies on diclofenac sodium pulsatile release pellets].

AIM: To investigate the preparation of diclofenac sodium pulsatile release pellets (DS-PRP), the release in vitro and the pharmacokinetics of the drug. METHODS: Diclofenac sodium (DS) core pellets prepared by extrusion-spheronization technology were coated in a mini-fluidized bed spray coater with swelling material as the inner coating swelling layer and ethylcellulose aqueous dispersion as the outer coating controlled layer. The effects of formulation and medium on pulsatile release of DS were investigated under release rate test. Pharmacokinetic and bioavailability study in eight human subjects were performed by HPLC method. RESULTS: The delayed-release time and release rate of DS from DS-PRP were influenced obviously by the swelling material, the concentration of SDS in medium, the coating level of the inner swelling layer and the outer controlled layer. In vitro, the delayed-release time T0.1 was 3.1 h, and the pulsed-release time T0.1-0.2 was 1.2 h. In vivo, the delayed-release time Tlag was 2.8 h, and the bioavailability was (91 +/- 12)%. CONCLUSION: The release of drug from DS-PRP was shown to be in pulsed way both in vitro and in vivo.

Adult↗

PubMed2002

[Studies on heart-protecting musk pH-dependent gradient-release pellets].

AIM: To prepare heart-protecting musk pH-dependent gradient-release pellets and investigate the drug release in vitro and in vivo. METHODS: The pH-dependent gradient-release pellet system was prepared by using HPMC, Eudragit L-30D-55 and Eudragit L100-Eudragit S100 (1:5) combinations as coater. The release of borneol and total ginsenoside from pH-dependent gradient-release pellets were determined according to the method of Pharmacopoeia of the People's Republic of China (2000) in the simulated gastrointestinal pH conditions. The gastrointestinal transit and disintegration of pellets was investigated by using gamma-scintigraphic trace in volunteers. The pharmacokinetics of borneol of heart-protecting musk pH-dependent gradient-release pellets was studied in 6 healthy volunteers by GC methods. RESULTS: The f2 value of release data of borneol and total ginsenoside of the heart-protecting musk pH-dependent gradient-release pellets was 79.6 in the simulated gastrointestinal pH conditions. The gamma-scintigraphic trace evaluation demonstrated that the pellets coated with HPMC, Eudragit L-30D-55 or Eudragit L100-Eudragit S100 (1:5) combinations can disintegrate in stomach, duodenum and jejunum or ileum. The gastrointestinal transit time of pellets was about 5 hours in fasted state and about 6 hours in fed state. The concentration-time curves of borneol of heart-protecting musk pills fit in two-compartment model. The pharmacokinetics data showed that borneol had a short time of absorption and elimination. The mean residence time (MRT) of borneol of heart-protecting musk pills was 2.61 hours. The plasma concentration of borneol of heart-protecting musk sustained-release capsule which consisted of three kinds of pellets coated with HPMC, Eudragit L-30D-55 or Eudragit L100-Eudragit S100 (1:5) combinations was steadier than those of heart-protecting musk pills, its Cmax was lower than and Tmax was near to those of heart-protecting musk pills, its MRT was 4.0 hours, and its relative bioavailability was 96%. CONCLUSION: The lipidsoluble borneol and watersoluble total ginsenoside of heart-protecting musk pH-dependent gradient-release pellets can release simultaneously while sustained-releasing in vitro. The heart-protecting musk pH-dependent gradient-release pellets had the characteristics of pH-dependent gradient-releasing and disintegration while transiting in gastrointestinal tract. A characteristic of gradient sustained-release was shown in the concentration-time curves of borneol of heart-protecting musk sustained-release capsule in volunteers.

Adult↗

PubMed2002

[Study on the preparation of venenum bufonis beta-cyclodextrin inclusion complexes].

OBJECTIVE: To study the preparation of Venenum Bufonis beta-cyclodextrin inclusion complexes. METHOD: An optimal condition was established by the uniform design. Under the optimal conditions the Venenum Bufonis beta-cyclodextrin inclusion complexes were prepared with 5 different methods. RESULT: The ball grinding method was superior to other four methods. The bufadienolide inclusion rate of Venenum Bufonis beta-cyclodextrin prepared with ball grinding method was 85.42%. CONCLUSION: Ball grinding method is the best method for the preparation of Venenum Bufonis beta-cyclodextrin inclusion complexes.

Amphibian Venoms↗