1.Effect of heparin/dihydroxy-iron complex multilayeres nanomodification on biocompatibilities of decellular xenograft
Yunming TAO ; Tiehui HU ; Zhongshi WU ; Hao TANG ; Yerong HU ; Qi TAN
Chinese Journal of Thoracic and Cardiovascular Surgery 2012;28(2):94-98
Objective Xenografts have poor biocompatibilities,the aim of this study was to improve the biocompatibilities of decellular xenografts via heparin/dihydroxy-iron complex multilayeres (HDCMs) nanomodification.Methods A novel thrombo-resistant surface for decellular xenograft had been developed by alternating linkage of dihydroxy-iron and heparin to decellular bovine jugular vein (DC-BJV),and surface characterization and biocompatibility of HDCMs nanomodified BJV (HDCMs-BJV) were detected.Results Toluidine blue colorimetric method showed the amount of linked heparin was about (808 ±86) μg/cm2 per assembly-cycle.SEM images proved HDCMs were uniformly linked to and formed nanoscale films around the fibrils of DC-BJV.Washing test proved HDCMs were firmly linked to BJV and sustainedly released heparin for a long time.Tensile test showed that biomechanical stability was increased.Antithrombogenicity test showed that the activated partial thrombin time (APTT) and prothrombin time (PT) of all trial groups were above the normal reference ranges.Platelet adhesion test evaluated mean platelet count per 10 000 μm2 area was 8 ±4 for HDCMs-BJV vs.48 ± 16 for DC-BJV.Endothelial cells (ECs) proliferation test showed the number and activity of ECs on luminal surface of HDCMs-BJV were very similar to DC-BJV at 7-day incubation.Calcium content assay evaluated mean calcium content was ( 8.5 ± 1.9 ) μg/mg dry weight for HDCMs-BJV vs.(26.6 ± 3.7) μg/mg dry weight for DC-BJV at 4 weeks and (21.5 ± 6.8 ) μg/mg dry weight for HDCMsBJV vs.( 112.6 ± 16.9) μg/mg dry weight for DC-BJVs at 8 weeks,respectively.Conclusion These results demonstrate HDCMs were firmly linked to BJV and formed nanoscale thrombo-resistant films,and HDCMs nanomodification improves biocompatibilities of decellular xenograft.
2.Short term effect of gastric bypass surgery for the treatment of nonobese type 2 diabetes mellitus
Lijun TANG ; Tao CHEN ; Jianfeng GUI ; Li SHI ; Hongtao YAN ; Yunming LI ; Fuzhou TIAN
Chinese Journal of Digestive Surgery 2011;10(3):214-216
Objective To investigate the short term effect of gastric bypass surgery for the treatment of nonobese type 2 diabetes mellitus and possible mechanisms. Methods The clinical data of 58 patients with nonobese type 2 diabetes mellitus who received gastric bypass surgery from March to August, 2009 were retrospectively analyzed. The levels of fasting plasms glucose (FPG), 2-hour postprandial plasma glucose (2h PG) and glycosylated hemoglobin (HbA1c) were dynamically monitored, and the insulin resistance index (HOMA-IR) and body mass index ( BMI) were calculated. All data were analyzed using variance of analysis and LSD test. Results Of the 58 patients, 48 (83% ) met the requirement of complete response criteria and stopped administration of hypoglycemic agents; 7( 12% ) had to use hypoglycemic agents, but the dose of the agents was lowered by 50% compared to that before surgery. The surgery was ineffective in 3 patients (5% ). The levels of FPG, 2h PG, HbAlc and HOMA-IR of the 58 patients showed a significant decreasing trend after surgery when compared to those before surgery (F = 67. 867, 50. 885, 78. 278, 572. 757, P <0.05), while there was no significant change of the BMI after surgery ( F = 3. 503, P > 0. 05 ). Conclusions Gastric bypass surgery has a good effect on nonobese patients with type 2 diabetes mellitus whose BMI was less than 25 kg/m2. The improvement of insulin resistance after the surgery might be the main reason.
3.Heparin-iron complex multilayer nanomodification improves hemocompatibility of decellular xenograft.
Yunming TAO ; Tiehui HU ; Zhongshi WU ; Hao TANG ; Yerong HU ; Qi TAN
Journal of Central South University(Medical Sciences) 2012;37(3):260-266
OBJECTIVE:
To improve the hemocompatibility of decellular vascular matrix via heparin-iron complex multilayers (HICMs) nanomodification.
METHODS:
A novel thrombo-resistant surface for decellular xenograft was developed by alternating linkage of dihydroxy-iron and heparin to decellular bovine jugular vein (DC-BJV), and its surface characterization, biomechanical stability and hemocompatibility were detected by scanning electron microscopy, tensile test and hemocompatibility evaluation, respectively.
RESULTS:
A toluidine blue colorimetric method indicated the amount of linked heparin was about (808±86) μg/cm2 per assembly-cycle. Scanning electron microscopic (SEM) images proved that HICMs were uniformly linked to and formed nanoscale films around the fibrils of DC-BJV. Toluidine blue staining histologic images showed that HICMs were linked mainly to DC-BJV surfaces. Washing test showed that the release of heparin was (281±43), (422 ± 60), (729±81), (1053±116), (1317±157), (1618±187) and (1945 ± 268 ) μg/cm(2) at 1 day, 1, 2, 3, 4, 6 and 8 week washing, respectively. Tensile tests showed an increased biomechanical stability. Hemocompatibility evaluations showed that PT and APTT of all the trial groups were above the normal reference ranges and that mean platelet count per 10000 μm2 area was 8±4 for HICMs layer-by-layer modified BJV (LBL-BJV) vs 48±16 for DC-BJV.
CONCLUSION
HICMs are firmly linked to DC-BJV, and can form nanoscale thrombo-resistant films, which yield a sustained release of heparin. HICMs nanomodification improves the hemocompatibility of decellular xenograft.
Animals
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Biocompatible Materials
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Blood Vessel Prosthesis
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Cattle
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Cell-Free System
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Coated Materials, Biocompatible
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chemical synthesis
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chemistry
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pharmacology
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Heparin
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administration & dosage
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chemistry
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Iron
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administration & dosage
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chemistry
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Jugular Veins
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Nanostructures
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chemistry
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ultrastructure
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Surface Properties
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Tissue Scaffolds
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Transplantation, Heterologous
4.Enhanced efficiency of stannous penetration and lipopolysaccharide neutralization by a novel stabilized stannous-containing sodium fluoride dentifrice
Linhua LIU ; Yunming SHI ; Hongmei LI ; Tao HE ; Jiahui LI ; Yanyan HE ; Ross STRAND ; Weili DONG
Journal of Practical Stomatology 2017;33(6):758-762
Objective:To evaluate the dental biofilm penetration efficiency of a novel stabilized stannous-containing sodium fluoride dentifric(EXP) and its lipopolysaccharide (LPS) neutralization efficiency.Methods:A controlled,randomized,examiner-blind in situ clinical trial was conducted with the treatment of PBS(control),EXP and a marketed stannous-containing sodium fluoride dentifrice (MKD).Fluorescent dye,fluorescent probe and fluorescence colocalization were used for sample examination and analysis.Results:EXP offered better stannous penetration into the biofilm than MKD and PBS(P <0.05),as well as greater LPS neutralization efficiency(P <0.05).There was a 96.52% overlap of stannous ions and bounded LPS at the same sites treated by EXP.Conclusion:EXP is more effective than MKD in the delivery of stannous into the biofilm and in the neutralization of LPS.