Objective To investigate the clinical features, treatments and prognoses of pediatric intracranial aneurysms. Methods The clinical and follow-up data of 16 consecutive patients with pediatric intracranial aneurysms (≤16 years), admitted to our hospital from January 2003 to December 2014, were analyzed retrospectively. Results Pediatric intracranial aneurysms in this study accounted for 0.78%of all intracranial aneurysms. Of the 16 children, 14 were male, 2 were female. There were 12 anterior circulation aneurysms and 5 posterior circulation aneurysms; there were 4 large aneurysms (diameter 11-25 mm) and 2 giant aneurysms (diameter≥25 mm);there were 14 complex aneurysms. At a mean follow-up duration of 16.8 months, no death was noted. Of the 12 patients received microsurgical therapy, 10 patients had favorable outcomes (modified Rankin scale [mRS] 0-1) and 2 patients had some sequelae: different degrees of disability (mRS 2-4). Of the 4 patients received endovascular therapy, 3 patients had favorable outcomes (mRS 0-1) and one patient had hemiparesis (mRS 2). Conclusions Pediatric intracranial aneurysms are different from adult intracranial aneurysms. The treatment effects and prognosis are relatively well when we select individualized treatment mode according to the clinical features of pediatric intracranial aneurysms.

BACKGROUND: Studies have shown that chitooligosaccharides have antitumor effect. However, the influence of chitooligosaccharides on cyclin D1, bcl-2 and bcl-xl remains unclear.OBJECTIVE: To observe the JnhJbJtJon effect of chitooligosaccharides on the proliferation of Hela cells, and the influence on cyclin D1, bcl-xl and bcl-2 mRNA expression.METHODS: Hela cells were stimulated by different concentrations of chitooligosaccharides (0.1, 0.5, 1, 2, 5 g/L). The effects of chitooligosaccharides on Hela cells were detected by CCK8 kit. Using real-time PCR methods, the gene expression of cyclin D1, bcl-xl and bcl-2 mRNA were determined.RESULTS AND CONCLUSION: Chitooligosaccharides inhibited the proliferation of Hela cells. With the concentrations of chitoolJgosaccharides increased from 0.1 g/L to 2 g/L, the inhibition effects on the gene expressJon of cyclin D1, bcl-xl and bcl-2 were enhanced, peaked at 2 g/L, and decreased at high concentration (5 g/L). Antitumor activity of chitooligosaccharides may exert through two aspects: it inhibits cyclin D1 mRNA expression to suppress the proliferation of tumor cells; on the other hand, chitooligosaccharides inhibits the expression of bcl-xl and bci-2 to promote the apoptosis of tumor cells. Moreover, the effects of the former are stronger than the latter.

BACKGROUND: Microspheric injectable scaffold has a perspective in cartilage tissue engineering; however, it is still limited by in vivo hard forming and microsphere transmigration.OBJECTIVE: To investigate the feasibility of self-assembly scaffolds by attaching negatively charged calcium alginate microspheres and positively charged chitosan microspheres by electrostatic force. METHODS: The calcium alginate and chitosan microspheres were prepared by emulsion-internal gelation and spray drying technique, respectively. The characterizations of the microspheres were determined by means of scanning electron microscopy, optical microscopy and zeta potential analysis methods. Self-assembly scaffolds were fabricated by mixing the aqueous suspensions of the microspheres with oppositely charged surfaces. The phenomenon of electrostatic attachment was characterized by optical microscopy and scanning electron microscopy, and the elastic compress modulus of the scaffolds was also investigated.RESULTS AND CONCLUSION: The average diameter of the calcium alginate microspheres was 52.5 μm, and the chitosan one was 4.1 μm, respectively. The zeta-potential of the calcium alginate microspheres was 23.5 mv, and the chitosan one was +9.8 mv, respectively. The microspheres were spherical and smooth. The small size chitosan microspheres could attach to the surface of the calcium alginate microspheres and anchor the calcium alginate microspheres together. The elastic compress modulus increased with the increase of solid content of the microspheres, but decreased with the increase of the ionic strength. The elastic compress modulus increased firstly and then decreased with the increase of the mass ratio of m (CHI):m (ALG), and it showed the highest elastic compress modulus when m (CHI):m (ALG) was 2:1. The positively charged chitosan microspheres could attach to the negatively calcium alginate microspheres to form a self-assembly scaffold.

Transcription factor NF-κB has attracted attention due to its important role in the regulation of the expression of a number of cellular genes involved in host defense, inflammation/immune responses, cytokine and growth factor regulation, cell survival, proliferation, and also in embryonic development and programmed cell death. In this review, we provide an overview of established TNF-α, TLR/IL-1R, TCR and BCR signaling pathways to NF-κB, the alternative NF-κB pathway, and the regulation of NF-κB transcriptional activity. Furthermore, we discuss on emphasis the cross-talks between NF-κB and other signaling pathways (TGF-β, p53, nuclear receptor family, Ras/MEK/MAPK...), which are very complex and remain to be understood. The activation or inhibition of NF-κB has effect on other signaling pathways. They compose a complex signaling network, in which many regulatory signals integrate systematically and coordinate transcriptional responses to the stimulations. So when NF-κB is used as an important target of drugs in human diseases, the pathological and physiological functions of related signal pathways also should be understood sufficiently.

Objective To study the effect of a novel injectable scaffold material chitosan- beta-TCP combining bone marrow mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP) on repairing bone defect of goat. Methods The model of the studies was 12ram diameter circular hole tibia bone defect of goat. 30 Chinese goats were raudomly divided into 5 groups: blank group: nothing was embeded in bone defect; simple material group: the material embeded in bone defect was chitosan-beta-TCP; PRP group: the material was chitesan-beta-TCP combining PRP; MSCs group: the material was chitosan-beta-TCP combining MSCs; PRP/MSCs group:the material was chitosan-beta-TCP combining MSCs and PRP. At 4,8 weeks after operation, the samples were observed, histological and image analysis were used to evaluate the effect of bone regeneration. Results At 8 weeks, the surface of bone defect zone of PRP/MSCs group were coverd by continuous new bones, like normal bone. Histological slice showed the esteoid at boundary of normal bone of MSCs/PRP group obviously increased compare to other groups at the 4th or 8th week after operation respectively. The new bone tissues of bone defect were punctiform or lamellar new bone tissues, in which the proportion of big lamellar new bone tissue obviously increased. Image analysis showed that the areas of balnk group, simple material group, PRP group, MSCs group, PRP/MSCs group were 8.79±3.63,14.49± 3.72,24.18 ± 5.38,24.42 ± 5.10,31.10 ± 3.49 at 4 weeks and 15.41 ± 4.21,25.36 ± 5.37,30.71 ± 4.39, 33.97 ± 4.45,48.60 ± 5.97 at 8 weeks respectively. The effect of bone regeneration of PRP/MSCs group was better than other groups (P < 0.05). Conclusion The injectable tissue-engineering bone constructed with chitosan-beta-TCP, MSCs and PRP possesses good ability on repairing bone defect.

Compound membranes of chitosan/hydroxyapatite were prepared by blending. The physical performance showed that the air-water contact angles decreased from chitosan's 103 degrees to chitosan/hydroxyapatite's 57 and the water adsorption rate increased slightly. When immersed into culture medium, the materials adsorbed Ca2+, and low crystalline hydroxyapatite deposited on the surface of the membranes. Chitosan/hydroxyapatite compound membranes could enhance the attachment and proliferation of mescenchymal stem cells (MSCs). After 12 days' induction on the materials, the alkaline phosphatase (ALP) activity value of MSCs on the compound membrane was 10.1, being much higher than 1.6 on chitosan membrane (P<0.01). All these results indicate that chitosan does not have very good affinity for MSCs, but the biocompatibility of chitosan can be apparently enhanced after mixing with hydroxyapatite. The compound membrane stimulates MSCs to differentiate into osteoblasts and it may be a good potential material for bone substitution.
Alkaline Phosphatase ; metabolism ; Animals ; Bone Substitutes ; pharmacology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Chitosan ; chemical synthesis ; pharmacology ; Durapatite ; chemical synthesis ; pharmacology ; Membranes, Artificial ; Mesenchymal Stromal Cells ; cytology ; Rats

In recent years, the applications of atomic force microscopy (AFM) have underpinned the fast progress in the area of tissue engineering. Besides the study of surface morphology in the dimension of micro- and nano-, AFM has played an important role in the fabrication of micro- and nano-structure as well as in the investigation of mechanical properties of material and cell. This overview is aimed to introduce the principle of AFM and to review its recent applications in tissue engineering.
Humans ; Microscopy, Atomic Force ; Nanotechnology ; Tissue Engineering ; trends ; Tissue Scaffolds

BACKGROUND:Polylactic acid(PLA)surface is hydrophobic and there are no nataral recognition sites,so its application is limited.Many different strategies have been studied such as composition and chemical Drafting,to produce hydrophilic groups.However,these traditional methods are always involved in complex process and many organic reagents,resulting in decrease of biocompatibility.OBJECTIVE:To conduct the surfacr modification of PL.A and improve its hydrophilicity with low temperature plasma treatment.DESIGN:Controlled observation.SETTING:Department of Materials Science and Engineering in Jinan University.MATERIAIS:The experiment was processed from October 2004 to October 2005 at Guangzhou Research Center of Artificial Organs and Materials Engineering(Ministry of Education).The mainly used materials were:Poly-D,L-lactic acid(Mr 2.9×104,Shandong Medical Instrument Institute),N-vinyl-pyrrolidone(NVP,Acros Company,purified before use).METHODS:The materials were treated in the plasma reactor under different conditions(power=150 W,t=3,2,1 minutes;power=30 W,t=10,8,5,3,1 minutes)to choose the optimal condition,and then PLA were grafted with NVP by gas phase polymerization and liquid polymerization,respectively.MAIN OUTCOME MEASURES:THe surface morphology of the films was observed with scanning electron microscopy and atomic force microscopy.The hydrophilicity of native and treated material surfaces was measured using a water contact angle meter.Surface composition was detected with Fourier transform infrared spectrometer.Mass changesmeasurement was applied to characterize the grafting efficiency.RESULTS:Scanning electron microscopy and atomic force microscopy showed that the plasma medified materials possessed coarse surface with pores and notches.Water contact angles decreased obviously from 78°to 50°after grafting,Fourier transform infrared spectrometer showed a new absorption peak at 1 637.19 cm-1,which corresponded to the carbonyl stretch vibration absorption of amide group in poly-N-vinyl-pyrrolidone.After the plasma treatmerlt at low temperature.the mass change ratio of PLA film material was-0.6.CONCLUSION:The plasma treatment and polymerization can improve the hydrophilicity and cause coarsr surface of PLA material,which will be helpful for the cell attachment.

A new method was used for treating the natural bone. A series of natural bone materials were treated mainly by Supercritical Carbon Dioxide Fluid Technology (SC-CO2-FT) and chemical ultrasound marination. The treated bone materials were determined by scanning electron microscopy, X-ray diffraction and thermo gravimetric analyses. The results showed that the sizes of bone, the sequence of processes as well as the time effected the treated bone. The treated bone material still maintained its natural porous structure, and its wall was quite clear; moreover, the hydroxyapatite crystals kept good crystalline structure. Compared to traditional treatments, the new treatments were beneficial to delipidation and proteic extraction and were not in need of organic solvent. The results demonstrated that this new method is promising in the treatment of natural bone.
Animals ; Biocompatible Materials ; Bone Substitutes ; chemical synthesis ; Chromatography, Supercritical Fluid ; Durapatite ; Femur ; chemistry ; Swine

A novel cornea tissue scaffold material was prepared with N-vinly pyrrolidome (NVP) and a biodegradable crosslinking agent by radical polymerization, using azoisobutyronitrile (AIBN) as initiator. Water absorption test and contact angle measure were conducted, and the degradation process of material was investigated. The biocompatibility evaluation was carried out by implantation of material in the rabbits, and by cell culture. The water absorption was over 104%, the contact angle was lower than 41degrees, and the degradation speed in vitro kept steady. The results of implantation in the rabbits showed that the material was almost degraded 3 months later and lots of collagen and cornea stroma cells appeared in it,but there was no inflammation around it. The result of epithelial cells culture showed that the cells conglutinated on the material, but no remarkable cytotoxicity was noted.
Animals ; Biocompatible Materials ; chemistry ; Cornea ; cytology ; Epithelium, Corneal ; cytology ; Materials Testing ; Nitriles ; chemistry ; Prostheses and Implants ; Pyrrolidinones ; chemistry ; Rabbits ; Tissue Engineering