BACKGROUND:In comparison with stem cel s from other tissues, adipose-derived stem cel s (ADSCs) are not only abundant and easy to harvest but also have the strong abilities to proliferate and differentiate. These make ADSCS the promising stem cel s in the field of oral tissue regeneration. OBJECTIVE:To summarize the biological features of ADSCs and the development of functions as stem cel s in the oral tissue regeneration. METHODS:We took“adipose-derived stem cel s, oral tissue regeneration, bone tissue engineering, periodontal tissue regeneration, bone defects”as the key words in Chinese and English, respectively, to retrieve the related literatures from PubMed, CNKI, Wangfang databases during 2000 to 2016 based on internet search. RESULTS AND CONCLUSION:In vitro studies on periodontal tissue regeneration have shown that ADSCs can promote the regeneration of bones, fibroblasts, blood vessels around the periodontal area, and improve the healing abilities of injured tissues. In the study of craniofacial bone regeneration, ADSCs can successful y repair massive bone loss due to the surgeries of tumor or accidents. ADSCs have a promising role in the oral tissue regeneration, but further studies wil be required because of the problems of immunogenicity and safety.

BACKGROUND: Shape memory polyurethane (SMPU) may be employed for bone repair capable of resisting stress shielding and bone non-union due to the shape memory effect responding to changed external temperature. Evaluating the cytocompatibility of SMPU is important for its further in vivo experiments and applications. However, few have been done to investigate the cytocompatibility of SMPU after encounted from deforming and shape recovering.OBJECTIVE: To evaluate the osteoblast compatibility of SMPU before and after stretching-shape recovering process. METHODS: Solvent casting method was used to fabricate SMPU films; the obtained SMPU films were stretched to 200%, and then fixed and finally recovered to its odginal shape at T_g+15 ℃, T_g-15 ℃ and T_g+15 ℃, respectively. Atomic force microscope (AFM) with tapping mode was employed to probe the surface morphology and phase separation of SMPU. Primary osteoblasts at 3-5 passages were seeded on SMPU films in vitro to evaluate the adhesion, proliferation and spreading of osteoblasts. RESULTS AND CONCLUSION: There were obvious and regular phase separation resulted from soft segments and hard segments in SMPU, and some groove-ddge architectures within a scale of micrometers were produced by the stretching-shape recovering process. These special micropatterned structures promoted osteoblast adhesion and proliferation, and also resulted in partially oriented cell growth along the grooves. Shape memory process, i.e. stretching-shape recovering process may obviously change the surface morphology of SMPU films, and suggesting better biocompatibility with osteoblasts.

OBJECTIVE:To provide reference for standardizing the clinical use of carbapenem antibiotics and controlling drug-resistant bacteria infection. METHODS:The detection of 3 kinds of carbapenems-resistant Gram-negative bacillus in our hospi-tal during 2011-2016 were analyzed retrospectively. The consumption,target cure rate and treatment course of carbapenem antibiot-ics were analyzed statistically. The correlation between detection rate of drug-resistant bacteria with the consumption of carbapenem antibiotics was investigated by Pearson test. RESULTS:During 2011-2016,1222 strains of carbapenems-resistant Acinetobacter bauman (CRAB),655 strains of carbapenems-resistant Pseudomonas aeruginosa (CRPA) and 53 strains of carbapenem-resistant Escherichia coli (CRE) were detected in our hospital. The detection rates increased from 23.88%,8.92%,0.09% in 2011 to 80.34%,35.74%,0.97% in 2016. The types of carbapenem antibiotics in our hospital were mainly imipenem and meropenem. The consumption of them increased from 4222,145 g in 2011 to 7218,4387 g in 2016. The both target cure rates were all lower than 60%,and the proportion of the patients with treatment course >14 d was more than 65%. The detection rates of CRAB,CR-PA and CRE were positively correlated with the consumption of carbapenem antibiotics (r>0.9,P<0.05). CONCLUSIONS:The detection rate of carbapenems-resistant Gram-negative bacillus and drug consumption increase year by year in our hospital,and they have certain correlation. The target cure rate of carbapenem antibiotics in our hospital is in low level,and there is a long treatment course. They are should be standardized in the clinic. The selection of carbapenem antibiotics should be strictly followed clinical in-dications so as to reduce the generation of drug-resistant strains.

OBJECTIVETo investigate the effect of novel porous calcium phosphate cement (CPC) scaffoldings on attachment, proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs).

METHODSBMSCs of Beagle dogs were implanted and cultured with CPC scaffoldings in vitro, tricalcium phosphate (TCP) and poly (lactide-coglycolide) (PLGA) scaffoldings as controls. The attachment, proliferation and differentiation of BMSCs were detected through morphological characters, growth curve and the semi-quantitative detection of alkaline phosphatase (ALP) and osteocalcin (OC) activity.

RESULTSCell morphology and growth curve illustrated that BMSCs attached to and grown better on the surface of novel porous CPC scaffoldings than that of PLGA group (P < 0.05). Semi-quantitative analysis of ALP showed that ALP expression level in BMSCs on the CPC and TCP group were significantly higher than that of the PLGA group (P < 0.05), the CPC group was slightly higher than the TCP group, but no significant difference was found between the two groups (P > 0.05). The staining and semi-quantitative analysis results of OC demonstrated that calcium deposition of the PLGA group was significantly less than the CPC and TCP group on both observation point (P < 0.05), but no significant difference between the CPC and TCP group (P > 0.05).

CONCLUSIONThe novel porous CPC material used in this study has good biocompatibility similar to TCP but much better than PLGA which is favorable of BMSCs adhesion, proliferation and osteogenic differentiation. The novel porous CPC material is a suitable scaffolding for BMSCs to fabricate tissue-engineered bone in vitro.

Animals ; Bone Marrow Cells ; Bone and Bones ; Calcium Phosphates ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Dental Cementum ; Dogs ; Osteocalcin ; Osteogenesis ; Tissue Engineering

Objective:To investigate the effects of icaritin(ICT)on the proliferation and osteogenic differentiation of rat bone mar-row stromal cells(rBMSCs).Methods:rBMSCs were cultured from the bone marrow of SD rats and identified by multilineage differ-entiation assays.3,6 and 9 days after the treatment of rBMSCs of passage 4 by ICT at 1 0 -9 ,1 0 -8 ,1 0 -7 ,1 0 -6 and 1 0 -5 mol/L re-spectively,the proliferation and differentiation of the cells were examined by cck-8 and alkaline phosphatase (ALP)activity assay kit respectively.The calcium nodule formation was observed by alizarin red(AR)staining 21 days after 1 0 -9 mol/L ICT treatment. Results:Primary rBMSCs showed the typical spindle-like shape with attachment growth.rBMSCs could be induced to osteogenic and adipogenic differentiation.The proliferation of rBMSCs was inhibited but ALP activity was enhanced by ICT.1 0 -9 mol/L ICT in-cresed calcium nodule formation.Conclusion:ICT can dose-dependently inhibit the proliferation,but promote the osteogenic differ-entiation of rBMSCs.

An in vitro model was built for researching the effects of strain on vascular smooth muscle cells (VSMCs). The cultured VSMCs was stretched by four-support-bending-beam system, then the project area of cells was measured by computer-image-processing, the adhesion force was measured by micropipette-aspirating system, the α-actin of VSMCs was distinguished by immunocytochemistry and the dynamic of VSMCs was determined by FCM. The results show that: (1) The adhesion force of VSMCs is positively related to time. The adhesion force of unit area is indistinct after stretched for four hour. (2) The amount of α-actin increases with stretching time. (3) The proliferation of VSMCs is a little inhibited by stretched 24 h. These results suggest that the VSMCs in vitro could adjust their behavious to adapt the tension.

ObjectiveTo evaluate the impact of iFlow in the auxiliary diagnosis of cerebral vascular diseases.Methods Totally 65 patients with cerebral vascular diseases underwent whole brain 2D DSA.Then the data were converted to color coded images with iFlow.The vascular anatomy,the shape and size of lesions,the blood dynamics on 2D DSA and iFlow images were evaluated by junior and senior physicians,who then reported whether iFlow images had supplementary diagnosis value.ResultsiFlow images displayed whole information of lesions more clearly than those of 2D DSA in brain vascular dynamic sequence,including vascular anatomy,hemodynamic changes and tissues perfusions.The evaluation of 2D DSA and iFlow images with junior and senior physicians had statistical difference (x2 =6.032,P=0.014).ConclusionCompared to single DSA,iFlow can facilitate the diagnosis and evaluation of cerebral vascular diseases,especially for junior physicians.

Objective To investigate the correlation between gastric polyps and helicobacter pylori (Hp) infection .Methods 150 patients with gastric polyps(experimental group) and 150 patients with chronic gastritis(control group) from October 2011 to No-vember 2012 in Shapingba people′s hospital of Chongqing were enrolled in this study .The polyps biopsy in patients with gastric polyps and the mucosa in gastric antrum big and small bends ,and the anterior and posterior walls(about 2-5 cm from the pylorus) from both groups were detected for the pathological type ,inflammation degree and stained(modified Giemsa staining) for detection of the existence of Hp .Results In 150 patients with gastric polyps ,58% (87/150) of the cases were infected by Hp mainly in medi-um and low degree ,in which 39 .3% (59/150) of the infection located at polyps and 42% (63/150) of the infection occurred out of polyps .Pathological analysis for this group further demonstrated that the types of hyperplastic polyps ,fundic gland polyps ,inflam-matory polyp and adenomatous polyps accounted for 68 .0% (102 cases) ,20 .7% (31 cases) ,9 .3% (14 cases) and 2 .0% (3 cases) of total 150 gastric polyps cases ,of which 63 .7% (65/102) ,38 .7% (12/31) ,57 .1% (8/14) and 66 .7% (2/3) cases were infected by Hp ,respectively .Pathological analysis also indicated that ,among total 150 gastric polyps cases ,single polyps and multiple polyps types accounted for 62 .0% (93 cases) and 38 .0% (57 cases) .The polyps commonly existed at gastric fundus in which the incidence rate of the hyperplastic polyps type and the fundic gland polyps type were 94 .1% (96/102) and 87 .1% (27/31) ,respectively .The infection rate in hyperplastic polyps was markedly higher than that in fundic gland polyps (P<0 .05) ,and the infection of hyperplas-tic polyps was mainly medium and high degrees .In addition ,the inflammatory response in the hyperplastic polyps was higher ,ac-companied by the intestinal metaplasia and atrophy of gastric mucosa ,as compared with non-hyperplastic polyps .In the total 150 control cases ,52 .0% (78/150) patients were infected by Hp with mainly medium and high degree .Results indicated that there is no relationship between polyps occurring and Hp infection .Conclusion Compared to the chronic gastritis ,there is no positive associa-tion between gastric polyps and Hp infection .There is no remarkable difference for Hp infection rate and degree between the polyps and the non-polyps sites in the stomach .The infection rate and infection degree of hyperplastic polyps is significantly higher than that of fundic polyps .However ,the underlying mechanisms for the development of hyperplastic polyps have to be elucidated in the future .

BACKGROUND:Osteogenesis is closely integrated with angiogenesis in bone formation and repair process, and hypoxia-inducible factor 1 alpha (HIF-1α) is considered to be the most important core transcription factor promoting angiogenesis gene regulation, which may promote the formation of blood vessels at hypoxia portion, and thus contribute to bone formation.
OBJECTIVE:To construct the Lenti-HIF-1α-IRES-EGFP (wild type) and Lenti-HIF-1α-IRES-EGFP (point mutant type) lentiviral eukaryotic expression vectors and to detect their impact on the osteogenic gene expression of rabbit bone marrow mesenchymal stem cells.
METHODS:The Lenti-HIF-1α-IRES-EGFP (wild type) and Lenti-HIF-1α-IRES-EGFP (point mutant type) lentiviral eukaryotic expression vectors were constructed according to the wild type human HIF-1αgene sequence and the determined restriction sites of human HIF-1αpoint mutant sequence. Rabbit bone marrow mesenchymal stem cells were transfected with the prepared Lenti-HIF-1α-IRES-EGFP (wild type) and Lenti-HIF-1α-IRES-EGFP (point mutant type) virus solution.
RESULTS AND CONCLUSION:Immunofluorescence microscopy observations indicated that the cells of Lenti-HIF-1α-IRES-EGFP (wild type) group and Lenti-HIF-1α-IRES-EGFP (point mutant type) group showed no obvious fluorescence on transfected 7 days, and two groups of cells showed a more obvious green fluorescent after transfection 14 days. Quantitative PCR analysis results showed that there were obvious HIF-1αand bonemorphogenetic protein 2 gene expressions on days 7 after transfection and the two genes stil showed highly expression levels after transfection 14 days. The two lentiviral eukaryotic expression vectors of Lenti-HIF-1α-IRES-EGFP (wild type) and Lenti-HIF-1α-IRES-EGFP (point mutant type) could be constructed according to the wild type human HIF-1αgene sequence and the determined restriction sites of human HIF-1αpoint mutant sequence;HIF-1αgene can promote the osteogenic gene expression of lentivirus-transfected rabbit bone marrow mesenchymal stem cells.

A processing technique has been developed to prepare acellular bone collagen matrix (ABCM) and ABCM-PDLLA composite materials. The properties of these materials were characterized through several different methods. The histocompatibility of the materials were investigated by ELISA (enzyme linked immunosorbent assay) test and healing the defection of New Zealand white rabbit bilateral radius. The spectroscopy indicated that the major inorganic and organic components of the bone blocks were carbonated hydroxyapatite and collagen respectively,and the fatty and cellular components were. completely eliminated. The test results also revealed that the materials had good mechanical property and well-internnected pore structure, and the addition of PDLLA increased the strength of the materials. The ELISA results demonstrated that the materials had low immunogenicity in short order, and the degree of immune response caused by ABCM was greater than that by ABCM-PDLLA. All of the grafts exhibited good osteoconductive ability and a new bone form after the creeping substitution. In conclusion, two kinds of materials with good histocompatibility have been prepared, and owing to its good mechanical performance and low immunogenicity, ABCM-PDLLA is a better candidate for bone substitute and bone tissue engineering scaffold when compared with single ABCM.
Animals ; Biocompatible Materials ; Bone Substitutes ; chemistry ; Cattle ; Collagen ; chemistry ; Durapatite ; chemistry ; Extracellular Matrix ; chemistry ; Implants, Experimental ; Lactic Acid ; chemistry ; Materials Testing ; Polyesters ; Polymers ; chemistry ; Rabbits ; Random Allocation ; Tissue Engineering ; methods ; Tissue Scaffolds