Objective To investigate the feasibility, effect and mechanism of chemical bile duct embolization for chemical hepatectomy. Methods Phenol or absolute ethanol plus cyanonacrylate were employed as embolization agents. Histology, Fas and TGF-? 1 measurement were used to evaluate the result. Results Phenol plus cyanonacrylate effectively destroyed and embolized intrahepatic biliary duct, leading to complete disappearance of hepatocytes in the periphery of embolization lobe and thereby achieving the effect of chemical hepatectomy. Expression of Fas and TGF-? 1 in phenol embolism group (88.90?38.10, 185.22?70.39) and ethanol embolism group (72.39?29.51, 163.56?51.75) were higher than those in biliary duct ligated group (26.31?12.07, 74.84?40.73) ( P

Sixteen goats with fractures of right femur received cortical bone plates allografts on both the sides of femurs. The right allograft strut endured the stimulation of physiological stress, and the left allograft strut did not. Groups of goats were sacrificed and specimens were procured at 3, 6, 12, and 24 week after surgery for histology observation and image analysis of the vessels after Chinese ink perfusion, the rate of bone porosity, the integrated optical density (IOD) of tetracycline fluorescence labeling and new bone formation were investigated in order to evaluate the incorporation of the allograft strut. The allograft strut revascularized at 6 weeks after surgery in the fracture group, but at 3 weeks in the control group. The rate of area of vessels after Chinese ink perfusion, the rate of bone porosity, the integrated optical density (IOD) of tetracycline fluorescence labeling and new bone formation in the fracture group were worse than control from 3 weeks to 6 weeks, but the observed and measured values were better in the fracture group than in the control group beyond 6 weeks after surgery (P < 0.05). The stimulation of stress would be harmful to the allograft strut if the strut endured the stress at an earlier period postoperation. Yet, it would be beneficial to the revascularization, new bone formation, substitution, and internal re-building on the strut provided that the extremity was immobilized for 6 weeks; and if the cortical graft endured the stimulation of physiological stress from 6 weeks postoperation till cancellous conjunction between the ends of fractures, the revascularization on the allograft strut and the bone conjunction between partially allograft strut and host would be faciliated.
Allografts ; Animals ; Biomechanical Phenomena ; Bone Plates ; Bone Transplantation ; Femoral Fractures ; Femur ; physiology ; Goats

Mesenchymal stem cells (MSC) are thought to be multi-potent cells that have the potential to differentiate into lineages of mesenchymal tissues, including bone, cartilage, tendon, fat, muscle, and marrow stroma during embryo morphogenesis. In recent years, cells that have the characteristics of mesenchymal stem cells were isolated from marrow aspirates of human and a few animals. It was found that these cells retain the characteristics of stem cells in vitro and could be induced to differentiate exclusively into the osteocytic, chondrocytic, myoblastic and adipocytic lineages. It was demonstrated that MSC could heal clinically significant bone and cartilage defects in animal models. The role of MSC in repairing tendon defect was also testified. In addition, for its multi-potential to differentiate into lineages of mesenchymal tissues, MSC could be used as gene vehicle for gene therapy of trauma care.
Animals ; Bone Marrow Cells ; physiology ; Bone Marrow Transplantation ; Bone and Bones ; injuries ; surgery ; Cartilage ; injuries ; surgery ; Cell Differentiation ; Cells, Cultured ; Stem Cells ; physiology ; Tissue Engineering

In this paper the background and advances of stem cell technique in stomatology were reviewed, especially the lately research of repair of maxillofacial defects with bone marrow stem cells, repair or reconstitution of teeth with dental pulp stem cells and repair of other tissues such as parotid with embryonic stem cell. Stem cell technique provides a new choice and extensive prospect of application for stomatology, therefore, deserves further research.
Oral Medicine ; Stem Cell Transplantation ; methods ; Stem Cells ; cytology

The temporary function replacement and intensive support play a pivotal role in the treatment of patients with acute or chronic end-stage organ failure. The hemodialysis and peritoneal dialysis have become routine techniques in the management of acute or chronic renal failure. But for the complexity of hepatic function, e.g. metabolism, biosynthesis and biotransformation for endogenous or exogenous substrates, the simulation or partial replacement of hepatic function is a great dream of bionic technologists. With the development of cell biology and biomedical material, the combination of biomaterial and the hepatocyte cultured ex vivo could provide a range of human liver-specific functions. The combination of biomaterial and viable cell was called hybrid or bioartificial liver support system (BALSS). It is a chimera of biomaterials and hepatocytes. The bionic technologists study the cell and its culture in vitro, which is the main component of BASLL. Many types of BALSS were translated into the early clinical stage. In this overview, we review the hepatocyte culture and the design of different bioreactors. It includes the immune obstacles in xeno-hemoperfusion and how to assess pre-clinical and clinical effectiveness.
Bioreactors ; Cells, Cultured ; Hepatocytes ; cytology ; Humans ; Liver, Artificial

BACKGROUND:Oversize stress of a dental implant and its surrounding tissue is the main factor to affect the
long-term use of dental implants. So, the reasonable and precise design of implant shape is one of the important methods of prolonging the life span of dental implants.
OBJECTIVE:To make the optimal analysis and design of the diameters of connector screw and central screw of the adjustable-angle dental implant invented in the earlier stage.
METHODS: The finite element analysis model of the edentulous mandible with adjustable-angle dental implant was established by software Pro/E 5.0, Mimics 10.0 and ANSYS Workbench 14.5. The maximum equivalent
stress of dental implant-edentulous mandibular model was analyzed.
RESULTS AND CONCLUSION:The maximum equivalent stress of dental implant-edentulous mandibular model

This study was aimed to create strontium-calcium sulfate compounds for making a new bioactive material with osteoconductive and osteoinduceable activity for bone repairing. Its mechanics and degradation features were assessed in vitro. Powders of alpha-calcium sulfate hemihydrate (alpha-CSH) and SrCl2 were mixed completely to make Sr-calcium sulfate compounds materials with 6 different concentrations (0%, 0.1%, 0.3%, 0.5%, 1% and 2%) of Sr. Scanning electron microscope was used to observe the configuration of the new materials. The compressive strength of each material was tested. The materials were soaked into simulated body fluid (SBF) to test the features of degradation, which included pH, weight loss, declination of compressive strength and the changes of strontium ion concentration. The crystal appearances were influenced by incorporating of strontium. The compressive strength of non-strontium incorporating calcium sulfate was 36.65 +/- 2.22 MPa. When the concentration of strontium was increasing, the compressive strength measurements of the materials tended to decline. The compressive strength declined to 20.56 +/- 2.64 MPa when the strontium concentration reached to 2%. The pH value of the SBF declined when the time of degradation increased, but both of them were very stable. All of the materials got weight loss after being soaked in SBF for several weeks. The weight loss was slight within 4 weeks and it became dramatic after 4 weeks. When the concentration of strontium was increasing, the weight loss became more rapid and significant (P<0.05). During 0-4 weeks' degradation in SBF, the materials' compressive strength decreased much slower when the strontium concentration was below 0.5%; however, when the decrement of strength became faster, the strontium concentration became higher. The concentration of strontium ion in SBF began to increase faster after 4 weeks' soaking in SBF. As the concentration of strontium was increasing, the strontium ion concentration in SBF became higher (P = 0.000). The new compound materials made by the mixing of alpha-calcium sulfate hemihydrate and SrCl2 can provide efficient compressive strength. The features of degradation of the materials are very stable. The new materials can release lots of bone inducible substance-strontium ions to repair bone defection after 4 weeks of degradation.
Bone Substitutes ; chemical synthesis ; chemistry ; Calcium Sulfate ; chemistry ; Compressive Strength ; Humans ; Osteogenesis ; Strontium ; chemistry

New bone formation in long-term intramuscle implant of Ca-P biomaterial was investigated in this experiment. After implanting into dog dorsal muscle for 15 months, a thin fibrous membrane that wrapped HA/TCP implant was still observed obviously. Three types of tissues, i.e. mesenchymal tissue, bone and bone marrow, regularly distributed in different pores of implant. Nearly all the pores of implants were occupied by bone. Bone in the pores located in the central region of implant was matured lamellar bone characterized by obvious lacuna and rich bone marrow. However, bone in the peripheral pores was immature woven bone without bone marrow formation. Furthermore, mesenchymal tissues only exist in the peripheral pores and usually were connected with immature woven bone. It was demonstrated that porous HA/TCP has bone inductivity and it could induce new bone formation at non-osseous site. Well-regulated distribution of mesenchymal tissue, bone and bone marrow in the pores suggest bone morphogenesis in the implant must obey a specific space-time program.
Animals ; Biocompatible Materials ; Bone Substitutes ; pharmacology ; Ceramics ; pharmacology ; Dogs ; Hydroxyapatites ; pharmacology ; Implants, Experimental ; Materials Testing ; Osteogenesis ; drug effects

In order to explore the possibility of applying enzyme histochemistry in biocompatibility evaluation, we investigated the effect of biomaterials on the activities of intracellular enzymes in this experiment. It was found that there was no obvious difference in morphology between osteoblasts co-cultured with HA/TCP and with Ti-alloy. However, transient down-regulation of NADH, SDH, LDH and CCO of the osteoblasts co-cultured with HA/TCP was detected by enzyme histochemistry, but these enzymes of osteoblasts the co-cultured with Ti-alloy were not down-regulated. It was indicated that something extracted from HA/TCP injured the co-cultured osteoblasts slightly. Similar early acute inflammatory reactions were observed after HA/TCP and Ti-alloy were separately implanted into the dorsal muscle of rabbit. There was also no obvious difference between the tissue response to HA/TCP and that to Ti-alloy. Activities of enzymes in tissues around implanted materials were down-regulated at the early injury period and recovered gradually within 30 days post-operation. But the mild toxicity of extracts from HA/TCP was demonstrated by the fact that the recovery period of HA/TCP group was longer than that of Ti-alloy group. It was proved that enzyme histochemistry is more sensitive than tissue morphology analysis in detecting the cell or tissue responses to biomaterials. Therefore, it is possible to use enzyme histochemistry in biocompatibility evaluation.
Alloys ; Animals ; Biocompatible Materials ; chemistry ; Calcium Phosphates ; chemistry ; Cells, Cultured ; Ceramics ; chemistry ; Coculture Techniques ; Female ; Histocytochemistry ; methods ; Hydroxyapatites ; chemistry ; Implants, Experimental ; Male ; Materials Testing ; Osteoblasts ; cytology ; Rabbits ; Titanium

It was previously thought that keratinocytes did not express the CD80 and CD86 which provide the most important costimulatory signals for the antigen-specific T-cell activation. The cultured keratinocytes allografts were initially accepted, but eventually, all grafted donor cells were gradually replaced by recipient cells. The precise mechanisms are not very clear. In this study, neonatal murine keratinocytes were cultured for 7 days, the results of flow cytometry and confocal microscopy showed that CD80 could be detected on keratinocytes, while CD86 could not be detected all the time. RT-PCR analysis confirmed this result. The expression level of the CD80 mRNA amplified significantly from day 1 to day 7, as expression of the control beta-actin, but CD86 was not detected. Mixed Lymphocyte Reaction (MLR) showed that keratinocytes cultured with 10% serum for 7 d stimulated effectively allogeneic rather than syngeneic T cell proliferation. This study demonstrated for the first time that costimulatory molecule CD80 can be expressed on keratinocytes in vitro. These data provided an alternative explanation for the ultimate rejection of allogeneic keratinocytes in which keratinocytes act as antigen-presenting cells.
Animals ; Animals, Newborn ; Antigen-Presenting Cells ; cytology ; B7-1 Antigen ; biosynthesis ; genetics ; B7-2 Antigen ; biosynthesis ; genetics ; Cells, Cultured ; Graft Rejection ; Keratinocytes ; cytology ; Lymphocyte Activation ; Lymphocytes ; immunology ; Mice ; Mice, Inbred BALB C ; RNA, Messenger ; biosynthesis ; genetics ; Skin ; cytology