Objective To study bioactivity of microencapsulated peripheral nerve tissue after transplanted into abdominal cavity and analyze the in vivo time-effect relation. Methods Microencap-sulated peripheral nerve tissues were injected into the abdominal cavity of mice. Results Microencap-sulated peripheral nerve could remain intact six months after transplantation. The peripheral nerve cells survived, with normal proliferation function. Conclusions Microencapsulated peripheral nerve tissues can remain bioactivity at least six weeks in vivo. Improved technique of microencapsulation may prolong bioactivity of microencapsulated peripheral nerve tissues and accordingly promote nerve regeneration fol-lowing peripheral nerve injury.

Objective To investigate the activity of gastrocnemius muscle after acellular nerve transplantation with microencapsulated peripheral nerve tissue to repair sciatic nerve gap in dogs. Methods Twelve dogs were selected and divided randomly into four groups with three in each. Both sciatic nerves of the dogs in group A were cut and chemically extracted to make acellular nerves. Acellular nerves were transplanted into the dogs of groups B and C to bridge 30 mm sciatic nerve gaps, and additionally microencapsulated peripheral nerve were added in group B. Autograft was used for repairing the defects in group D. The motor function of operated limbs were observed regularly after operation. Six months after operation, motor conduction velocity of the specimens of sciatic grafting nerve segment were observed, and the gastrocnemius muscle of both sides were obtained and performed succinic dehydrogenase (SDH), synaptophysin (SYP) and motor end plate histochemical staining, and sciatic nerve 1 cm from distal end stoma were obtained and underwent Masson, Luxol fast blue and NF200 staining. Results All the dogs in groups B, C and D were involved in the results analysis without loss. Image analysis indicated the optical density and the cross section area of gastrocnemius muscle, area and optical density of synaptophysin, area and optical density of motor end plate in group B showed statistically significant difference compared with those in group C, but no significant difference with those in group D. The results of motor function recovery of operated-limb, electrophysiological examination and morphologic observations of sciatic nerve were all consistent with the detections of gastrocnemius muscle. Conclusion The gastrocnemius muscle may be again innerved by nerve, and the muscle atrophy is significantly alleviated after acellular nerve transplantation with microencapsulated peripheral nerve tissue for repairing sciatic nerve gap. The regeneration of nerve was better after the combined transplantation than only acellular nerve transplantation, so the combination of acellular nerve and microencapsulated peripheral nerve tissue may be a useful substitute of autograft for nerve repair.

BACKGROUND:Studies have confirmed that the active ingredients ofPaeonia lactiflora Pal. have better inhibitory effects onCandida albicans, but its monomer paeoniflorin has not been reported whether it can inhibit Candida albicans biofilm. OBJECTIVE:To observe the effect of paeoniflorin onCandida albicans biofilm in vitro. METHODS:Paeoniflorin solution at different concentrations of 4, 2, 1, 0.5, 0.25 g/L was prepared using RPMI-1640 according to 2-fold dilution method. Chlorhexidine was diluted with RPMI-1640 to different concentrations, including 2%, 1%, 0.5%, 0.25%, 0.125%. We compared the effects of different concentrations of chlorhexidine and paeoniflorin on diameter ofCandida albicans by agar diffusion method. MTT assay was used to detect the effect of different concentrations of chlorhexidine or paeoniflorin on the celladhesion of Candida albicans as wel as their inhibitory effects onCandida albicans biofilms. Confocal laser scanning microscope and LIVE/DEAD BacLight Bacterial Viability Kits were combined to observe the changes ofCandida albicans biofilms under normal or intervention conditions. RESULTS AND CONCLUSION:Both chlorhexidine and paeoniflorin possessed bacteriostatic ability, and their bacteriostatic ring diameters were positively correlated with drug concentrations. Significant differences in the bacteriostatic ring diameter were observed between chlorhexidine and paeoniflorin, except between 2 g/L paeoniflorin and 1%, 2% chlorhexidine. Paeoniflorin at different concentration could inhibit celladhesion of Candida albicans as wel as inhibitCandida albicans biofilm. The inhibition rate was also positively correlated with drug concentrations. Under normal conditions, most of bacteria in the biofilms were alive, and there was a smal amount of dead bacteria after 48 hours. After intervention with paeoniflorin, the proportion of dead bacteria in the biofilms was increasing along with the concentrations of paeoniflorin. Compared with the chlorhexidine, paeoniflorin showed a lower bacteriostatic activity. These findings indicate that paeoniflorin has an obvious inhibitory action in Candida albicans biofilms in vitro.

Objective · To observe the changes of cerebral gray matter pre- and post-treatment with short term drugs in patients with schizophrenia. Methods · T1-weighted brain MRIs were obtained on a 3T scanner in 21 controls and 27 subjects with schizophrenia who were not given antipsychotic medication. The controls and 21 schizophrenia patients received the second scan after 8 weeks of antipsychotic treatment. Voxel-based morphometry (VBM) were used to investigate the differences in gray matter (GM), mainly about the regional GM volumes. Results · GM volumes were significantly smaller in the patient group than those of healthy controls in left cerebellum posterior lobe , left and right parahippocampalgyrus, left middle temporal gyrus(P=0.000, voxels>50). GM volumes extensively decreased after 8 weeks of antipsychotic-treatment compared with pre-treatment in the superior, middle, and inferior temporal gyri, superior,middle and inferior frontal gyri, parahippocampa gyri, cingulate gyri, right supramarginal gyrus, right cerebellum posterior lobe, and right lingual gyrus(P=0.000, voxels>50). Conclusion · Short term antipsychotic treatment (8 weeks) may have adverse effects on the gray matter of patients with acute schizophrenia by reducing the volume of gray matter.

Objective To investigate the effect of electrical stimulation of S_3 nerve root on improvement of intestinal mucosal barrier function in rabbits with acute complete spinal cord injury. Methods Model of paraplegia was built by injuring spinal cord in rabbits. Then, the rabbits with electrical stimulation of S_3 nerve root were set as experimental group and those without set as control group. Normal rabbits were set as normal group. Under aseptic condition, portal vein blood was collected for quantitative determination of endotoxin and bacterial culture ; and liver, spleen and mesenteric lymph nodes were collected for bacterial culture and strain identification. Liver, spleen, mesenteric lymph nodes and small intestines were collected from experimental group and control group for pathological HE staining; while small intestine were observed by light and electron microscopes. Results In control group, the intestinal mueosal barrier and the other organs were destroyed obviously, with higher level of Serum endotoxin and higher rate intestinal flora translocation than that in experimental group and normal group. In the experimental group, the electrical stimulation of S_3 nerve root could improve motility of the denervated intestine, with more defecation content, less destruction of the intestinal mucosa and lighter other organ damage compared with control group, serum endotoxin level was significantly reduced compared with control group but showed no statistical difference compared with normal group, with obvious decrease of bacterial translocation rate. Conclusions After spinal cord injury in rabbits, electrical stimulation of S_3 nerve root can facilitate intestinal tract motility, improve intestinal mucosal barrier function and hence alleviate endotoxemia and intestinal bacterial translocation, as is beneficial to reducing SIRS and MOBS.

BACKGROUND:The hardened acrylic resin bone cement composite after implantation into human body can resist an intensity of 78-93 MPa. But a large amount of heat energy is released by bone cement during the process of solidification and it wil kil normal cel s, leading to peripheral tissue necrosis. OBJECTIVE:To investigate the characteristics of induced knee joint osteoarthritis after application of acrylic resin bone cement composite as a bone substitute for subchondral bone. METHODS:Thirty male Japanese big ear rabbits were randomly and equal y divided into four experimental groups (A, B, C, D) and a blank control group. After removal of subchondral bone on the right medial tibial plateau, polymethyl methacrylate powder/hydroxyapatite composite materials were implanted in rabbits in the experimental groups A, B, C, and D. Rabbits in the blank control group were only subjected to exposure of periosteum on the left medial tibial plateau. At 3, 6, 9 and 12 weeks after removal of subchondral bone, rabbits in the experimental groups A, B, C and D were sacrificed, and subchondral bone specimens were taken for hematoxylin-eosin staining and matrix metal oproteinase expression analysis. At the same time, interleukin-1βand tumor necrosis factor-ɑ levels in the synovial fluid were determined. RESULTS AND CONCLUSION:Mankin score in the experimental group C was significantly higher than in the blank control group and experimental group A (P<0.05). Mankin score in the experimental group D was significantly higher than in the experimental group B (P<0.05). The gray scale of matrix metal oproteinase-1 was highest in the blank control group, fol owed by experimental groups A, B, C, and the last in the experimental group D (P<0.05). Interleukin-1β and tumor necrosis factor-ɑ levels in the synovial fluid were highest in the experimental group D, fol owed by experimental groups C, B, A and the last in the blank control group (P<0.05). These findings suggest that acrylic resin bone cement composite as a bone substitute for subchondral bone induces knee joint osteoarthritis and leads to increases in matrix metal oproteinase-1 and tumor necrosis factor-ɑ levels in the synovial fluid.

BACKGROUND:Mechano growth factor has the potential to activate muscle satelite cels and promote myogenic cel growth, and has dual roles in maintaining bone mass and repairing bone defects.
OBJECTIVE: To explore the mechanism underlying osteogenic differentiation of rabbit bone marrow mesenchymal stem cels promoted by the mechano growth factor.
METHODS:The best concentration and time of mechano growth factor to promote osteogenic differentiation of rabbit bone marrow mesenchymal stem cels were detected by MTT. The mRNA and protein expressions of alkaline phosphatase and osteocalcin were detected by qPCR and western blot, respectively. The phosphorylation level of AKT and mTOR were detected by western blot assay.
RESULTS AND CONCLUSION:The best concentration and time of mechano growth factor was 45 μg/L and 5 days for promoting the osteogenic differentiation of rabbit bone marrow mesenchymal stem cels. The expressions of alkaline phosphatase and osteocalcin at mRNA and protein levels were highest after 4-hour intervention with 45 μg/L mechano growth factor, and meanwhile, the phosphorylation levels of mTOR and AKT were also highest. These findings indicate that the mechano growth factor can promote the differentiation of rabbit bone marrow mesenchymal stem cels into osteoblastsvia PI3K/AKT pathway, and its best concentration and time are 45 μg/L and 4 hours, respectively.

Objective To investigate the intestinal pathophysiological mechanism of bacterial translocation and endotoxemia in rabbits with acute spinal cord injury (SCI). Methods Paraplegia was induced by injuring the spinal cord of 30 rabbits by the method of Fehlings. Twelve rabbits were used for recording the changes of gastrointestinal (GI) electrophysiology and colon pressure. The left 18 rabbits were experimental group and were killed in 24, 48 and 72 h after injury. The other 6 rabbits served as normal group. Under aseptic condition, samples of blood and mesenteric lymph node were collected for bacterial cultures and endotoxin detection. The small intestines were observed by light and electron microscopy. The colons were inspected by light microscopy. Results After SCI, the electrophysiology of the GI tract was changed especially at the middle and distal colon. The peristalsis of the middle and distal colon was reduced and sometimes even disappeared. In the early stage, the main pathology was hyperemia of blood vessel and infiltration of inflammatory cells. The interepithelial tight junctions became wider and the columnar epithelium was disintegrated. All of the pathological changes may lead to the destruction of the intestinal barrier. The endotoxin level were increased since 24 h after SCI and had statistically significant difference compared with that at 72 h (P0.05). Conclusion After SCI, the middle and distal colon dysfunction induces constipation, bacterial overgrowth, and blood flow congestion. These factors may accelerate the destruction of the intestinal barrier and lead to bacterial translocation and endotoxemia.

Objective To discuss the application of nano-hydroapatic crystals and polyamide composite(n-HA/PA66) for artificial vertebrae in treating thoracic or lumbar vertebrae tumor.Methods A total of 14 cases suffering from thoracic or lumbar vertebrae tumor underwent deuto-total vertebrae resection via anterior approach,then canalis vertebralis was deboosted,artificial vertebrae was implanted and fixed with screw-stick system.Fourteen patients,9 male and 5 female were admitted by our hospital from Dec 2003 to Sep 2005,aged 32 to 68 years old(average 50).The tumor located at T_(11) in 2 cases,T_(12) in 2,L_1 in 5,L_2 in 5.Pathological diagnosis showed 3 cases were of aneurysmal bone cyst,5 of hemangioma,2 of giant cell tumor,3 of metastatic thoracic lumbar vertebra tumor. Results The follow-up lasted 3-18 months,mean 10 months.The rate of bone graft fusion reached 85.7%,with no loosened internal fixation or breakage of screw or stick.No screw breakage or spinal instability occurred during the follow-up.All cases were alive till follow-up finished.Conclusion If the thoracic vertebral tumor compresses spinal cord seriously,the patients should be recommended for surgical treatment.Total vertebrectomy followed by reconstruction could relieve the compression caused by tumor and restore the stabilization of spine effectively.Artificial vertebrae is the ideal substitute material for bone transplantation,for it has good biocompatibility,high security,high rate of bone graft fusion and firm fixation.

Objective To provide better emergency and patient services in well-equipped comprehensive hospitals, the organization and wisdom therapeutic strategy are of great importance for the recovery of injured patients from the earthquake zone. Method From 12 May 2008, following the 8.0 Magnitude earthquake in Wenchuan county of Sichuan Province, six Chongqing hospitals with third class in grade A were involved in the rescue of the injured patients with great effort. A total of 533 patients were retreated and followed up from quake zone. All the patients were scored with ISS and AIS system. The profiles of the patients examined, operated and clinical infection investigation were documented. Results Of 533 patients, the number of the patients whose ISS is below 16 is 456 (83.6%), the number between 16 and 25 is 65 (12.2%), and the humor above 25 is 12 (2.3%). The patients were classfled based on their fracture parts as follows: head and neck (n = 42), face (n = 7), chest (n = 114), abdominal and cavitas pelvis (n =81), limb and pelvis (n =314), body surface (n =205), with 180 single fracture site, 139 of them being two combined fracture sites, and 114 of them being above three combined fracture sites. Thirty-two of the patients were suffered from amputation. The number of patients suffered from crushing syndrome reached 21, with 281 surgical operations in hospitals. Seventy-nine patients were suffered from infections including 87.3% of pre-hespital infections. The results from bacteria culture and antibiotic susceptibility showed that the infected bacteria mainly involved in Escherichia coli, Staphylococcus anreus, Staphylococcus haemolyticns, Klebsiella pneumoniae, Baumanii, Aerobacter cloacae, Pseudomonas aeruginosa, C type chain coccus, Bacillus aerogenes capsulatus. The antibiotic susceptibility to diverse bacteria has no obvious changes and exists partial overlapping, and infected patients should be given the treatment of cephalosporin, macrolide antibiotic and so on. Conclusions For the emergency conditions after the catastrophe, the comprehensive hospitals must be prepared to meet large quantities of severe trauma and infection therapy. The scientific selection of antibiotics in the combinative therapy is of great importance to the enhancement of early specific treatment, prevention of severe trauma complications and rehabilitation of patients.