Abstract An animal experiment had been conducted for the purpose to find out the possibility of application of instantaneous sustained limited expansion (ISLE). A total of 54 skin defects in 9 pigs were obtained and were divided into two groups. One group of the pigs were subjected to instantaneous sustained limited expansion, the others, as the control group, just received the tension suture. At the same time the blood supply of the skin was measured by laser doppler flowmeter (LDF). It was showed that microcirculatory perfusion of the ISLE group was considerably better than that of the control. Inaddition, the correlation between the blood flow of the skin and the expanding pressure, as well as the pathologic changes of the skin were discussed.
Thiry wistar rats were used and divided in 2 groups. A segment of 6mm was excised in the sciatic nerve which were then bridged with chitin and skelal muscle. at 4,8,12 weeks after operation, In the chitin group a satisfactory regeneration of nerve fibers was evident with electrophysiologic and histologic examinations, and HRP retrogade labelling evaluation. The possible mechanism of enhancing nerve regeneration of chitin was also discussed.
The influence on the wrist stability following ulnar head resection (Darrach s procedure)was studied. A series of X-ray films and arthrography of the wrist joint were taken before and after ulnar head re- section. The results showed that after ulnar head resection the radial deviation increased 3 degree(Plt;0.01). and the ulnar deviation 11.92 degree (Plt;0.001). The position of the lunate remained unchanged. Arthrography of the wrist joint demonstrated that 11 specimens had injury of the triangular fibrocartilage.The stability of the wrist joint would no doubt be certainly affected following the ulnar head resction.
Abstract In order to find a new method to repair large bone defect, the free periosteum autograft was investigated in experiment, and then the method was used clinically. In the experiment, a 6mm×18mm×5mm bone defect was made at upper end of both tibiae of 42 rabbites. The periosteum of each rabbit was cut into 1mm cubes, and implanted randomly into the tbial bone defect on one side and the other side was used as control. After 2, 4, 8 weeks, the bone defects of each group were examined for bone formation by roentgenography, radionuclide and histology. The results showed that the defects treated by free periosteum autografts healed twice as fast as the controls (its natural healing). The reason probably was that the periosteum provided with many osteogenic cells. On thebasis of these results, 21 cases of bone defects (the largest was 10.5cm×4cm×4cm, the smallest was 2cm×2cm×2cm) including 17 cases of benign bone tumor and4 cases of chronic osteomyelitis, were treated by free periosteum autografts. The defects were all healed, and the function of the joints was restored.
Abstract In order to study the influence of chitosan on bone infection, 27 New-Zealand rabbits were randomly divided into 3 groups. According to the Norden technique, the model of osteomyelitis of the tuberosity of tibia was produced experimentally by injection of staphylococcus aureus.Immediately following injection of the staphylococci, the chitosan gel, acetic acid solution and sterile distilled water were injected into the bones in the 3 groups respectively. The latter two groups were served as control. The severity of the infection was evaluated by clinical symptoms and signs, radiographicdata as well as the bone culture and bacterial counts. Compared the results from chitosan with the other two controls, it was found that the local injection ofchitosan could not reduce the incidence of bone infection, however, it could provide actual improvement when other data were concerned. The effects of chitosangel might be attributed to its bacteriostatic and immunological activity as well as its slow degradation in the body.
To observe the changes of intestinal bacteriology in acute necrotizing pancreatitis (ANP). Dog ANP model was induced by injection of sodium taurocholate with trypin into the pancreatic duct. All dogs were sacrificed on the seventh postoperative day, mucosal and luminal microflora of intestine were analyzed quantitatively. The blood and organs were collected for culture. The results showed that population levels of E.coli in the intestinal mucosa and the content in cecum of the ANP dogs showed much higher level than those of the controls (Ｐ＜0.01 or Ｐ＜0.05), while bifidobacterium and lactobacillus were decreased significantly (Ｐ＜0.01), resulting in reversal of bifidobacterium/E.coli ratio. Blood levels of endotoxin were 1-2 times higher in ANP group as compare with the controls. The positive rate of blood and organs were 100% in ANP dogs. E.coli were the major bacteria cultured. The results indicated that microecological disturbance could take place after the onset of ANP, which may take an important role on pancreatic infection complicating ANP.
ObjectiveTo investigate the effect of interleukin (IL)-23 receptor (IL-23R) overexpression on the balance of T helper 17 (Th17 cells)/regulatory T cells (Treg cells) in experimental autoimmune uveitis (EAU) mice. MethodsTwelve 8-week-old female C57BL/6J mice were randomly divided into LV-Ctrl group and LV-IL-23R group, with 6 mice in each group. Two groups of mice were injected with LV-Ctrl and LV-IL-23Rlentiviruses through the tail vein, respectively; 7 days after injection, the EAU mouse model was established by active immunization with vitamin A-binding protein 1-20 between photoreceptors. Starting from 13 days after immunization, the fundus of the mice was observed by indirect ophthalmoscopy every 2 days and clinical scores were performed; 30 days after immunization, hematoxylin-eosin staining was used to observe the histopathological changes of mouse retina. The levels of IL-17 in serum of the two groups of mice were detected by enzyme-linked immunosorbent assay; the proportion of Th17 cells and Treg cells was detected by flow cytometry. The relative mRNA expression of IL-23R, IL-17, retinoic acid-related orphan receptor γt (RORγt), IL-10 and forkhead transcripyion factor p3 (Foxp3) were detected by real-time quantitative polymerase chain reaction. Comparisons between groups were performed using repeated measures analysis of variance, independent samples Mann-Whitney U test, and independent samples t test. ResultsCompared with the LV-Ctrlgroup, the retinal inflammatory reaction of the LV-IL-23R group was more severe. At 13 days after immunization, there was no significant difference in fundus inflammation scores between LV-IL-23R group and LV-Ctrl group (t=－2.001, P=0.058); 15-29 days after immunization. The fundus inflammation scores of LV-IL-23Rgroup were higher than those of LV-Ctrl group, and the difference was statistically significant (t=－4.429, －6.578, －7.768, －10.183, －6.325, －7.304, －4.841, －6.872; P＜0.001). Histopathological examination showed that the infiltration of inflammatory cells in the fundus increased, the retinal structure was damaged more seriously, and the histopathological score was significantly increased, and the difference was statistically significant (t=－4.339, P=0.001). Compared with the LV-Ctrl group, the relative expression of IL-23RmRNA in the spleen of the LV-IL-23R group was significantly increased, and the difference was statistically significant (Z=2.087, P=0.037). The relative expression of IL-17 and RORγt mRNA increased, while the relative expression of IL-10 and Foxp3 mRNA decreased, and the differences were statistically significant (t=－6.313,－5.922, 4.844, 7.572; P=0.003, 0.004, 0.008, 0.002). Compared with the LV-Ctrl group, the level of IL-17 in the serum of the mice in the LV-IL-23R group was significantly increased, and the difference was statistically significant (t=－5.423, P=0.002); the proportion of Th17 cells in the spleen and lymph nodes was significantly increased, whereas, the proportion of Treg cells was significantly reduced, and the difference was statistically significant (t=－4.290, 3.700; P=0.002, 0.006). ConclusionIL-23R overexpression can promote Th17/Treg imbalance in EAU mice, and aggravate the clinical and pathological manifestations of EAU.
Motor endplate is the structure connected between the nerve terminal and muscle fibre and plays a very important role in conducting nerve impulses to the target, therefore, systemical study of the sequential changes of the motor end-plate upon denervation is quite important.Ninety New Zealand rabbits were divided into nine groups from two weeks to nine months after denervation. Acetycholinesterase(AchE) was analyzed quantitatively to study the sequential changes of the motorendplates of tibialis anterior muscle. The results showed that there was no significant reduction of AchE at theend if one month after denervation, whereas a sharp reduction of AchE afterwards. AchE could not be stained after five month denervation.
ObjectiveTo observe the ability of osteogenesis in vivo using the injected absorbable polyamine acid/calcium sulfate (PAA/CS) composites and assess their ability to repair bone defects.
MethodWe selected 48 New Zealand white rabbits, and half of them were male with a weight between 2.0 and 2.5 kg. Bone defect models were made at the rabbit femoral condyle using electric drill, and the rabbits were divided into two groups. One group accepted implantation of the material at the defect, while nothing was done for the control group. After four, eight, twelve and sixteen weeks, the animals were killed. The line X-ray and hard tissue slices histological examination (HE, MASSON staining) were observed to assess the situation of degradation, absorption and bone formation of the material.
ResultsFour weeks after operation, bone defect of the experimental group had no obvious callus growth on X-ray imaging. Histology showed that the material began to degrade and new immature trabecular bone grew. The bone defect of the experimental group had a small amount of callus growth on X-ray imaging after eight weeks. And histology showed that the material continued to degrade and new immature trabecular bone grew continually. There was an obvious callus growth after twelve weeks, and the bone defect area had smaller residual low-density shadow on X-ray imaging. Histology showed that most of the materials degraded and parts of woven bone grew into lamellar bone. After sixteen weeks, the composites were absorbed completely, replaced by new bone tissues, and the new bone was gradually changed from woven bone into mature plate of bone. There was no significant change in bone defect in the control group within twelve weeks, and part of bone defect hole became smaller, and partial edge repair could be detected.
ConclusionsThe PAA/CS composites can be completely degraded and absorbed, with a certain activity of bone formation, expected to be used as bone repair materials.
In order to investigate the possibility of porous hydroxyapatite ceramics (HAC) in the repair of skull bone defect, twenty-four rabbits were used. The bone defect model was created by operation to obtain a defect in parietal bone in a size of 1 cm x 1 cm. Filled the defect with HAC and methyl-methacrylate-syrene copolymer (MMAS) to fill the defect as control. At 1st, 2nd and 3rd months after operation, behavior of the rabbits was observed and then these animals were sacrificed and specimens were examined under microscope. Results showed as follows: after operation, behavior of all animals were normal. By histological examination, it was found that in HAC group, there were granulation tissue, fibrous tissue and newly formed vessels grew into the pores and the osteoblasts formed osseous trabeculae. There was no inflammatory cell infiltration. In the MMAS grafted asea, there was formation of fibrous membrane. It suggested that HAC might be a good material for bone substitute in repair of skull bone defect.
