Low-temperature condensation deposition method for 3D printing of bone tissue engineering poly-L-lactic acid/pearl powder composite scaffold / 中国组织工程研究

BACKGROUND:The repair of large-scale bone defects is still facing serious challenges.It is of great significance to develop personalized,low-cost,and osteogenic-inducing tissue engineering scaffolds for bone repair. OBJECTIVE:To explore the process of 3D printing bone tissue engineering scaffold containing pearl composite material by low-temperature condensation deposition method,and further test the physicochemical properties and in vitro biological functions of the composite scaffold. METHODS:Pearl powder was prepared by grinding and sieving.The pearl powder of different qualities was added into the poly-L-lactic acid ink,so that the mass ratio of pearl powder to poly-L-lactic acid was 0,0.1,0.2,0.3,and 0.5,respectively.The 3D-printed poly-L-lactic acid/pearl powder scaffolds were prepared using the low-temperature condensation deposition method.The microstructure,compressive properties,water contact angle,cytocompatibility,and in vitro bone differentiation ability of the printed poly-L-lactic acid/pearl powder composite scaffolds were detected. RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that the five groups of scaffolds all had micropores with a diameter of 2 μm or even smaller,irregular shapes and interconnectivity.(2)All the five groups had good compressive properties.The compressive strength of the pearl powder 0.5 group was higher than that of the other four groups(P<0.05).The water contact angle of the pearl powder 0.2 group and the pearl powder 0.5 group was smaller than that of the pearl powder 0 group(P<0.01,P<0.001).(3)Bone marrow mesenchymal stem cells were co-cultured with five groups of scaffolds for 1,3,and 5 days,respectively.The cell proliferation in pearl powder 0.1,0.2,0.3,and 0.5 groups cultured for 3 and 5 days was faster than that in pearl powder 0 group(P<0.05).After 1 day of culture,live-dead staining exhibited that the number of cells on the scaffold was small,but all of them were living cells.(4)Bone marrow mesenchymal stem cells were inoculated on the scaffold surface of the pearl powder 0 group and pearl powder 0.1 group respectively for osteogenic differentiation.The alkaline phosphatase activity induced for 4 and 6 days in the pearl powder 0.1 group was higher than that in the pearl powder 0 group(P<0.05).(5)The results showed that the poly-L-lactic acid/pearl powder composite scaffold had good compressive strength,hydrophilicity,cytocompatibility,and osteogenic properties.

In vitro biocompatibility of 3D printed polycaprolactone/nano-hydroxyapatite composite scaffold with bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND: Polycaprolactone/nano-hydroxyapatite composite is a new composite scaffold material prepared based on common bone tissue engineering materials using 3D printing technology. At present, little is reported on the in vitro biocompatibility of the composite material. OBJECTIVE: To investigate the cytocompatibility of 3D printed polycaprolactone/nano-hydroxyapatite composite scaffolds. METHODS: Polycaprolactone and polycaprolactone/nano-hydroxyapatite composite scaffolds were prepared by 3D printing technology to characterize the microstructure, porosity and mechanical properties of the two materials. Rat bone marrow mesenchymal stem cells were inoculated on the surface of the 3D-printed polycaprolactone and polycaprolactone/nano-hydroxyapatite composite scaffolds. Cell proliferation rate was detected by CCK-8 method. Cell growth on the scaffolds was observed by scanning electron microscopy and Live/Dead cell staining. RESULTS AND CONCLUSION: Two kinds of scaffolds had a three-dimensional network and interconnected structure. The fibers were arranged in a regular order and interlaced. There was no gap on the fiber surface, and the fiber spacing and diameter were relatively uniform. There was no significant difference in the porosity between two kinds of scaffolds (P > 0. 05). The elastic modulus of the composite scaffold was higher than that of the simple polycaprolactone scaffold (P < 0. 05). There was no significant difference in cell proliferation between two kinds of scaffolds after 1 day of culture. After 4 and 7 days of culture, cell proliferation on the composite scaffold was significantly faster than that on the simple polycaprolactone scaffold (P < 0. 05). Live/Dead cell staining showed that both polycaprolactone and polycaprolactone/nano-hydroxyapatite composite scaffolds had good cytocompatibility and high cell viability. A larger number of cells adhered to the polycaprolactone/nano-hydroxyapatite composite scaffolds. Scanning electron microscopy showed that cells grew well on two kinds of scaffolds and distributed on the surface and micropores of the scaffold. The secreted extracellular matrix appeared in filaments and surrounded the cells. These findings suggest that the polycaprolactone/nano-hydroxyapatite composite material prepared by 3D printing technology has abundant pores, exhibit good mechanical properties, and have good cytocompatibility and can be used as a scaffold material for tissue engineering.

Evaluation of in vitro cell and blood compatibility and in vivo analgesic activity of plant-derived dietary supplements / 中西医结合学报

OBJECTIVE@#In vitro cell and blood compatibility of three dietary supplements, comprised of multiple plant extracts, Pneumo Go (PG), Green active (GA) and Equistasi (Eq), and their main component, the phytocomplex Matrix U.B.® (Union Bio S.r.l.) (M), were evaluated. Moreover, preliminary in vivo tests were performed on GA in order to assess its ability to reduce pain in an animal model.@*METHODS@#Cell compatibility was determined using fibroblasts (NIH3T3) and primary adult human microvascular endothelial cells (HMVECad) and the neutral red uptake test. Blood compatibility was evaluated by analyzing blood parameters after incubation of the products with sodium citrate anticoagulated whole blood. Thrombin time was determined by adding thrombin to aliquots of human plasma containing the samples. Clotting time was revealed by an automatic coagulometer. The in vivo analgesic effect of GA was evaluated in Wistar rats using the formalin test.@*RESULTS@#M and PG reduced the percentage of viable NIH3T3 cells, indicating their interference in the cell cycle. GA and Eq stimulated fibroblast proliferation and neutralized the toxic effect of M. M and PG reduced HMVECad cell viability. GA and Eq did not affect cell viability as well as negative control. The hemocompatibility tests indicated that all the samples did not interfere with fibrinogen. The in vivo test carried out in male rats showed a significant analgesic effect of GA in all formalin-induced pain behaviors.@*CONCLUSION@#No hemotoxicity and good cell compatibility were found for all the tested samples. GA and Eq were the best candidates for further biocompatibility testing. Moreover, GA reduced pain in the animal model.

Preparation and characterization of rutile phase TiO₂ nanoparticles and their cytocompatibility with oral cancer cells

In the present study, rutile phase titanium dioxide nanoparticles (R-TiO₂ NPs) were prepared by hydrolysis of titanium tetrachloride in an aqueous solution followed by calcination at 900℃. The composition of R-TiO₂ NPs was determined by the analysis of X-ray diffraction data, and the characteristic features of R-TiO₂ NPs such as the surface functional group, particle size, shape, surface topography, and morphological behavior were analyzed by Fourier-transform infrared spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy, transmission electron microscopy, dynamic light scattering, and zeta potential measurements. The average size of the prepared R-TiO₂ NPs was 76 nm, the surface area was 19 m²/g, zeta potential was −20.8 mV, and average hydrodynamic diameter in dimethyl sulfoxide (DMSO)–H₂O solution was 550 nm. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and morphological observations revealed that R-TiO₂ NPs were cytocompatible with oral cancer cells, with no inhibition of cell growth and proliferation. This suggests the efficacy of R-TiO₂ NPs for the aesthetic white pigmentation of teeth.

Study on compatibility of self-assembled gel containing RGD amphipathic peptide with bone marrow mesenchymal stem cells / 重庆医学

Objective To analyze the compatibility of bone marrow mesenchymal stem cells (BMSCs) with amphiphilic peptide three-dimensional gel.Methods Three healthy 3-week old SD rats were taken for separating femur and tibia to obtain BMSCs,the BMSCs surface antigen was detected by flow cytometry;the 10 mg/mL RGD-cyclic amphiphilic peptide solution was added into the same volume of DMEM/F12 culture medium,after a few seconds,which was self assemble into three-dimensional gel.Three dimensional gel structure was observed by transmission electron microscope (TEM).1 × 106 cells/mL BMSCs suspension and RGDcyclic amphiphilic peptide were mixed to form a 3D culture system,1 × 106 cells/mL BMSCs suspension was mixed with polylysine to form a 2D culture system,the serum-free culture was conducted;the CCK-8 method was used to observe the cell growth situation,calcein acetoxy methyl ester/propidium iodide (PI) double standard staining was performed.The effect of RGD-cyclic amphiphilic peptide on the proliferation of BMSCs was observed by fluorescence microscopy.Results The separated and cultured BMSCs highly expressed CD29 and CD90,but lowly expressed or did not express CD34 and CD45;TEM showed that the gel was composed of multiple empty nanofibers with the nanofiber diameter of 2-5 nm and length of 100-1 000 nm;the molecular weight of synthetic peptides detected by mass spectrometry (MS) was 1 256.37,which was consistent with the theoretical value;the HPLC analysis showed that RGD-amphiphilic peptide purity was 95.88 ％;the calcein acetoxyl methyl ester/PI double staining showed that in the 3D culture system,a few BMSCs died after 30 min and the cells began to proliferate after 12 h,the proliferation was more active than that of 2D culture,and the difference was statistically significant (P＜0.05);CCK-8 cell count showed that the proliferation activity of 3D culture system was higher than that of 2D culture system,and the difference was statistically significant (P＜0.05).Conclusion RGD amphiphilic peptide has a good biocompatibility with BMSCs,and may become the tissue engineering scaffold material.

The Cytocompatibility Study of Zr-Cu-Al-Ag Alloy Coated by Micro-arc Oxidation / 现代生物医学进展

Objective:To study the cytocompatibility of Zr-Cu-Al-Ag alloy coated by micro-arc oxidation.Methods:Components of Zr-Cu-Al-Ag alloy coated by micro-arc oxidation in three different voltages of 300 V,350 V and 400 V,Zr-Cu-Al-Ag alloy as cast condition and TI6Al4V alloy were made for the test.The water extracted from the components were obtained according to national standard.The L929 cells were cultivated in vitro in the extracts of these components separately.The L929 cells,cultured in Dulbecco's modified Eagle medium supplemented with 10 ％ fetal calf serum,served as the negative control group.And cells,cultured in Dulbecco's modified Eagle medium supplemented with 10 ％ fetal calf serum and 64 g/L phenol,served as the positive control group.The cytocompatibility of these components were evaluated by MTT colorimetric.Results:The cytotoxicity of Zr-Cu-Al-Ag alloy coated by micro-arc oxidation is 0 grade.Microscopy showed that the morphology of L929 cells,cultured in the extracts of Zr-Cu-Al-Ag alloy coated by micro-arc oxidation were normal.There were no significant differences between micro-arc oxidationt and negative control groups.The cell multiplication curves of micro-arc oxidation and negative control groups were nearly overlapping and in the linearity increasing trend.The OD in micro-arc oxidation groups had no significant differences with negative control group (P＞0.05),but were higher than that of Zr-Cu-Al-Ag alloy as cast condition,TI6Al4V alloy and positive control groups (P＜0.05).Conclusions:The cytocompatibility of Zr-Cu-Al-Ag alloy has been improved by micro-arc oxidation technique.

Antibacterial activity and cytocompatibility of chitosan-nano-silver complex thermosensitive hydrogel / 中国生化药物杂志

Objective To explore the antibacterial activity and cytocompatibility of chitosan-nano-silver complex thermosensitive hydrogel. Methods There were 4 groups: group A (containing 1 ×10-5 chitosan-nano-silver complex thermosensitive hydrogel), group B (containing 5 ×10-6 chitosan-nano-silver complex thermosensitive hydrogel) , group C ( containing 2 ×10-6 chitosan-nano-silver complex thermosensitive hydrogel) , group D ( chitosan thermosensitive hydrogel ) .The antibacterial activity of the samples against six kinds of gram-negative bacteria, one kind of gram-positive bacterium, three kinds of fungi were measured by bacteriostatic circle.The cytocompatibility of the extraction to NIH-3T3 cells was studied by SRB. Results The antibacterial activity enhanced with the increasing of nano silver concentration in chitosan-nano-silver complex thermosensitive hydrogel, whose antibacterial activity was better than chitosan thermosensitive hydrogel; its extraction has no cytotoxicity, thus showed good cytocompatibility. Conclusion The chitosan-nano-silver complex thermosensitive hydrogel is a potential novel wound dressing.

Antimicrobial and cytotoxic activity of Ferula gummosa plant essential oil compared to NaOCl and CHX: a preliminary in vitro study

OBJECTIVES: The usage of medicinal plants as natural antimicrobial agents has grown in many fields including dental medicine. The aim of this in vitro study was three-fold: (i) to determine the chemical compositions of the Ferula gummosa essential oil (FGEO), (ii) to compare the antimicrobial efficacy of the oil with sodium hypochlorite (NaOCl) and chlorhexidine (CHX), (iii) to assess the toxic behavior of FGEO in different concentrations compared to 5% NaOCl and 0.2% CHX. MATERIALS AND METHODS: Gas chromatography/mass spectrometry (GC/MS) was used to determine the chemical compositions of the oil. The disk diffusion method and a broth micro-dilution susceptibility assay were exploited to assess the antimicrobial efficacy against Enterococcus faecalis, Staphylococcus aureus, Streptococcus mitis, and Candida albicans. The cytocompatibility of the FGEO was assessed on L929 fibroblasts, and compared to that of NaOCl and CHX. RESULTS: Twenty-seven constituents were recognized in FGEO. The major component of the oil was beta-pinene (51.83%). All three irrigants significantly inhibited the growth of all examined microorganisms compared to the negative control group. FGEO at 50 microg/mL was effective in lower concentration against Enterococcus faecalis than 5% NaOCl and 0.2% CHX, and was also more potent than 0.2% CHX against Candida albicans and Staphylococcus aureus. FGEO was a cytocompatible solution, and had significantly lower toxicity compared to 5% NaOCl and 0.2% CHX. CONCLUSIONS: FGEO showed a promising biological potency as a root canal disinfectant. More investigations are required on the effectiveness of this oil on intracanal bacterial biofilms.

The study of cytocompatibility of Co-Cr alloy and Ti alloy / 天津医药

Objective To investigate the cytocompatibility of the liching liquids of Co-Cr alloy and Ti alloy on human gingival fibroblasts (HGF). Methods The HGF were treated in vitro with leaching liquids of Co-Cr alloy and Ti alloy, respectively. The DMEM cell medium containing 10% fetal bovine serum was served as a negative control. The viability of HGF treated by two dental alloys were evaluated by means of MTT, and the contents of intracellular reduced glutathione (rGSH) were assayed by kits. The tumor necrosis factor-α(TNF-α) contents were determined in the culture supernatant by ELISA in two groups. The effects of these alloys on the expression of caspase-3 were examined by real time-PCR method. Results Compared with the control group, HGF treated with Co-Cr alloy leaching liquids showed a lower viability ( P ＜0.05), while Ti alloy leaching liquid promoted the proliferation of HGF. In Co-Cr alloy group, the rGSH content was significantly decreased (P＜0.05), while TNF-α content was significantly increased (P＜0.05) compared with control group. There were no significant differences in rGSH and TNF-α contents between the Ti alloy group and control group (P＞0.05). The expression of caspase-3 was significantly higher in Co-Cr alloy group than that of control group (P＜0.05), while there was no significant difference in the expression of caspase-3 between Ti alloy group and control group. Conclusion Results suggest that Co-Cr alloy possesses cytotoxicity, while there is better cell compatibility for Ti alloy.

Applying Comparative of Anticoagulant and Thrombolytic Sak-Hirudin Fusion Protein Used in Cardiopulmonary Bypass / 现代检验医学杂志

Objective To investigate the applying comparative values of anticoagulant and thrombolytic Sak-hirudin fusion protein used in cardiopulmonary bypass.Methods From february 2013 to July 2014,selected nitinol sheet into uncoated group (group A),base coated group (chitosan,group B),chitosan/ Sak group (group C),chitosan/hirudin group (group D),chitosan/Sak-hirudin fusion protein group (group E),there were included in the fresh round of blood hemolysis,the blood cell hemolysis rates were calculated.Meanwhile used the healthy newborns umbilical vein endothelial cells were added into various categories nitinol sheet for cell compatibility testing.Results The samples hemolysis rates in the 5 groups were around 1.5% and the RBC,WBC and PLT counts compared in the 5 groups were showed no differences (P 0.05).Randomized double-blind cell count result shows that the group C,D and E compared to the group A,B were more significant differences (P <0.05), at the same time,the group E compared to the group C,D differences were statistically significant (P <0.05).Conclusion Compared to Staphylokinase and hirudin alone,Sak-hirudin fusion protein used in cardiopulmonary bypass can play stronger anticoagulant and antithrombotic effects,its safety and ensures the effectiveness that interventional treatment of cardiovascu-lar disease.

Comparison of Cytocompatibility Between Grit Blasted Titanium Alloy (Ti-6Al-4V) with or without Pure Titanium Coating / 대한정형외과연구학회지

PURPOSE: A composite of aluminum and vanadium (Ti-6Al-4V) is one of the most common compositions of titanium-based alloys. Unfortunately, vanadium has been found to cause adverse reactions. We evaluated the effects of vanadium containing titanium alloy (Ti-6Al-4V) on an osteoblast-like cell line (SaOS-2). MATERIALS AND METHODS: We studied the biologic and morphologic responses of SaOS-2 cell to Ti alloy with grit blasting and Ti coated Ti alloy with grit blasting. We performed energy-dispersive x-ray spectroscopy (EDS) and scanning electron microscopy (SEM) investigations and performed a cell proliferation assay, ALP activity, and cell migration assay of SaOS-2 cells. RESULTS: The morphologic assessment of cells through SEM showed that the two surfaces were covered with similar amounts of small slender osteoblast like cells. The amount of proliferation, ALP activity and the migration extent of SaOS-2 cells on the surfaces of each group were not statistically different. CONCLUSION: We used a grit-blasted Ti-coated Ti alloy, coated using electron beam deposition, and a grit-blasted Ti alloy to evaluate the toxicity of Ti-6Al-4V on SaOS-2 cell. Compared with pure titanium, the vanadium-containing Ti-alloy did not show an adverse effect on SaOS-2 cells.

Characterization and in vitro cytocompatibility of an acid-etched titanium surface

The aims of this study were to characterize the microstructure of a commercially pure titanium (cpTi) surface etched with HCl/H2SO4 (AE-cpTi) and to investigate its in vitro cytocompatibility compared to turned cpTi (T-cpTi). T-cpTi showed a grooved surface and AE-cpTi revealed a surface characterized by the presence of micropits. Surface parameters indicated that the AE-cpTi surface is more isotropic and present a greater area compared to T-cpTi. The oxide film thickness was similar between both surfaces; however, AE-cpTi presented more Ti and O and less C. Osteoblastic cell proliferation, alkaline phosphatase activity, and bone-like nodule formation were greater on T-cpTi than on AE-cpTi. These results show that acid etching treatment produced a surface with different topographical and chemical features compared to the turned one, and such surface modification affected negatively the in vitro cytocompatibility of cpTi as demonstrated by decreasing culture growth and expression of osteoblastic phenotype.

O objetivo deste estudo foi caracterizar a microestrutura de uma superfície de titânio comercialmente puro (cpTi) condicionada com HCl/H2SO4 (acid etched) (AE-cpTi) e investigar sua citocompatibilidade in vitro, comparada à do cpTi usinado (turned) (T-cpTi). O T-cpTi apresentou uma superfície com sulcos e o AE-cpTi exibiu uma superfície caracterizada pela presença de micro-vales. Os parâmetros de superfície indicaram que a superfície AE-cpTi é mais isotrópica e apresenta uma área maior quando comparada à superfície T-cpTi. A espessura da camada de óxido foi similar para as duas superfícies; no entanto, a AE-cpTi apresentou maiores quantidades de Ti e O e menor, de C. A proliferação de células osteoblásticas, a atividade de fosfatase alcalina e a formação de matriz mineralizada foram maiores na superfície T-cpTi que na AE-cpTi. Esses resultados mostram que o condicionamento ácido produziu uma superfície com características topográficas e químicas diferentes quando comparadas às da superfície usinada. Além disso, observou-se que essas modificações de superfície afetaram de forma negativa a citocompatibilidade in vitro do cpTi como demonstrado pela inibição da proliferação celular e da expressão do fenótipo osteoblástico.

Cytocompatibility study of multi-channel chitosan-alginate scaffolds / 中国矫形外科杂志

[Objective]To evaluate the cytocompatibility of chitosan-alginate scaffolds through in vitro cytoxicity experiment,cell-material co-culture experiment and in vivo implantation test.[Method]Chitosan-alginate scaffolds with longitudinal,paralleled multi-channels were produced via freeze-drying. Bone marrow derived stromal cells (BMSCs) were cultivated with the leach liquor. The cytotoxicity of scaffold was analyzed using MTT assay after 1,3 and 5 days of culture.Scanning electron microscopy was conducted after 3,5 and 7 days of BMSCs culture on the chitosan-alginate scaffold in vitro. Immunofluorescence detection was performed after implanting BMSCs and chitosan-alginate scaffolds in vitro in acute hemi-transaction spinal cord injury.[Result]The cytotoxicity of chitosan-alginate scaffold was in grade 0-1. Scanning electron microscopic observation indicated that the cells adhered to and grew on the surface of scaffold,arranging in a directional manner after 3 days of co-culture. NF200 and NSE fluorescence detection proved that a great many BMSCs were survival in the scaffold after 6 weeks,and that some transplanted cells differentiated into neuron-like cells.[Conclusion]Chitosan-alginate scaffold has a satisfactory cytocompatibility and may be an ideal tissue engineering scaffold material.

Cytocompatibility of thermally oxidized Ti-Ag alloys / 대한치과보철학회지

STATEMENT OF PROBLEM: In its preceding work, change in surface characteristics were investigated in consideration that both microtopograpy and macroscopic configuration of implants surface are two of the most important factors, in that they can construct agreeable environment by raising surface energy, to affect osseointegration and biocompatibility explained by cell proliferation. PURPOSE: This study focused on examining cytocompatibility of dental implants materials Ti-Ag alloys, of which mechanical and electrochemical superiority to cp-Ti or Ti6Al4V were verified, in comparison with that of cp-Ti, and Ti6Al4V. MATERIALS AND METHODS: In this regard, MTT tests for L-929, the fibroblast connective tissues and cell proliferation tests for osteoprogenitor cells, MC3T3-E1 were performed on cp-Ti, Ti6Al4V, and Ti-Ag alloys following thermal oxidation according to appropriate heat treatment temperature(untreated, 400, 600, 800degrees C) and heat treatment duration(untreated, 0.5, 1, 4 hr). RESULTS: The MTT tests on fibroblasts L-929 resulted in cell viability of over 90% in all experimental group entities, where, especially, the 100% of the viability for Ti-Ag alloys specimens accounted for the slightest adverse effect of ions release from those alloys on the cell. In MC3T3-E1 proliferation tests, the population of cells in the experimental group was roughly increased as experimentation proceeded, after two to four days. Proliferation showed highest viability for most of specimens, including Ti2.0Ag, treated at 600degrees C. CONCLUSION: In conclusion, it is the heat treatment temperature, not the duration that has considerable effects on thermal oxidation of specimens. Ti-Ag alloys treated at 600degrees C proved to have the best surface morphology as well as cytocompatibility when compared with Ti or Ti6Al4V for short-term biocompatibility tests.

A study on cytocompatibility of ion beam-irradiated chitosan sponges / 대한치주과학회지

Chitosan is a biodegradable and non-toxic material with a molecular weight of 800-1,500Kd which can be obtained in various forms with extraordinary chemical structures and biological characteristics of which enables it to be used in many fields as a biomaterial. Ion irradiation is a useful tool to modify chemical structures and physical properties of high molecular weight polymers. The basic hypothesis of this study is that when surface properties of chitosan in a sponge form are modified with ion beam-irradiation and cell adhesion properties of chitosan would improve and thereby increase the regenerative ability of the damaged bone. The purpose of this study was to illuminate the changes in the cytocompatibility of chitosan sponges after ion beam-irradiation as a preliminary research. Argon(Ar+) ions were irradiated at doses of 5x10(13), 5x10(15) at 35 keV on surfaces of each sponges. Cell adhesion and activity of alkaline phosphatases were studied using rat fetal osteoblasts. The results of this study show that ion beam-irradiation at optimal doses(5x10(13) Ar+ ion/cm2) is a useful method to improve cytocompatibility without sacrificing cell viability and any changing cell phenotypes. These results show that ion beam-irradiated chitosan sponges can be further applied as carriers in tissue engineering and as bone filling materials.

PRELIMINARY EVALUATION OF CYTOCOMPATIBILITY OF PEARLS OF PINCTADA MARTENSII / 中国海洋药物

This paper reports the results of cytotoxicity test of pearls of Pinctada martensii in vitro. The results of relative growth rate (RGR) and observation of cell morphology by putting up extracted solution of pearl powder in culture flask of L929 cell show that pearls of Pinctada martinsii are cytocompatible. The RGR of pearls of Pinctada martensti is lower than that of hy-droxyapatite.

Preparation of Medicinal Water-based Magnetic Fluid by One-step Method and Study on Its Cyto-compatibility / 中国药房

OBJECTIVE:To prepare medicinal water-based magnetic fluid and to study its cyto-compatibility.METHODS:Medicinal water-based magnetic fluids were prepared with microemulsion preparative technique by an one-step surface acting agent management method,the appearances and size distributions of which were detected by transmission elec-tron microscope and photon-related spectrograph.The influences of different concentrations of magnetic fluids on the in vitro cyto-compatibility of normal human liver cell strain(L-02)were detected by methyl thiazolyl tetrazolium(MTT)colorimetric assay and lactate dehydrogenase(LDH)delivery test,respectively.The characterization of the prepared solid magnetic fluid samples coated with monolayer and bilayer capric acid were conducted by infrared spectrometry,thermogravimetry,differential thermogravimetry and differential scanning calorimetry.RESULTS:The results showed that the grain size of the medicinal water-based magnetic fluids ranged from10nm to20nm.Phase separation or marked change in mean particle sizes were failed to be noted after storage for1year.The MTT and LDH tests results showed that medicinal water-based magnetic fluids were of no cytotoxicity to L-02but have good cyto-compatibility.CONCLUSION:Medicinal water-based magnetic fluids can be used in magnetic targeting drugs delivery system.

Study on biocompatability of nano-hydroxyapatite crystals and polyamide 66 composite with human embryonic fibroblast / 重庆医科大学学报

0.05).There was significant difference between every composite group with the positive group( P