1.Tissue-engineered acellular dermis repairs a skin ulcer:its preparation and healing mechanism
Peng DU ; Zhen GUAN ; Xiaochuan WANG
Chinese Journal of Tissue Engineering Research 2016;20(25):3738-3743
BACKGROUND: In recent years, acel ular human cadaveric dermis has been applied for repairing dermal defects and fil ing soft tissues, but this repair material is expensive and difficult to obtain. OBJECTIVE: To explore the repair effect of tissue-engineered acel ular dermis on wound healing of skin ulcer. METHODS: Sprague-Dawley rats were randomly divided into autologous reticular dermis and acel ular dermis groups. The tissue-engineered acel ular dermis was prepared by hypotonic solution, 2.5 g/L trypsin, 0.5% Triton X-100 and PBS solution, and in the meanwhile, a rat model of skin ulcer was established. Then, autologous skin graft and tissue-engineered acel ular dermis were transplanted into the autologous reticular dermis group and acel ular dermal group, respectively. Subsequently, comparative study about the repair effect and relative mechanism between two groups was performed. RESULTS AND CONCLUSION: The tissue-engineered acel ular dermis showed a white and grainy shape at room temperature. And hematoxylin-eosin staining showed that: the internal structure of tissue-engineered acel ular dermis exhibited a dendritic distribution, and the gap between col agen fiber bundles was relatively large. At 2, 3, 4 and 8 weeks after dermal transplantation, the survival rate of skin graft in the acel ular dermis group was significantly higher than that in the autologous reticular dermis group (P < 0.05). And the wound contraction rate in the acel ular dermis group was significantly higher than that of the autologous reticular dermis group at 3, 4 and 8 weeks after dermal transplantation (P < 0.05). In addition, the average diameter and clearance rate of col agen fibers in the normal skin around wound in the acel ular dermis group were significantly higher than those of autologous reticular dermis group (P < 0.05). To conclude, it is relatively simple to prepare tissue-engineered acel ular dermis under mild conditions, and the prepared tissue-engineered acel ular dermis presents a regular shape. Moreover, this acel ular dermis achieves desired outcomes in repairing dermal defects, which can promote wound healing by reducing the intradermal DNA residual and significantly improving some biomechanical properties in vivo.
2.Preparation and application of fluoroquinolones-loaded sustained-release chitosan microspheres
Peng CHENG ; Jing GUAN ; Hua ZHANG
Chinese Journal of Tissue Engineering Research 2009;13(16):3193-3196
There have been many methods to prepare fluoroquinolones-loaded sustained-release chitosan microspheres, including precipitation, emulsion crosslinking, spray-drying, and ionic gelation. Each of them has its own merits and disadvantages, but the mechanisms underlying drug delivery are basically similar. The prepared drug microspheres can enhance the capacity of anti-fluoroquinolones-resistant bacteria and are primarily used in the anti-inflammation and anti-infection. This paper introduces the preparation methods and sustained drug delivery mechanisms of fluoroquinolones-loaded sustained-release chitosan microspheres and investigates drug delivery characteristics and applications by analyzing, sorting, and summarizing related manuscripts published recently. Fluoroquinolones-loaded sustained-release chitosan microspheres show satisfactory sustained-release and anti-bacterial properties. Therefore, it is of important scientific research and clinical application significance to develop fluoroquinolones-loaded sustained-release nanometer-sized chitosan microspheres.
3.Revision hip arthroplasty with use of the acetabular reinforcement ring:8 cases follow-up study
Peng LI ; Zhanjun SHI ; Mingqiang GUAN
Orthopedic Journal of China 2006;0(11):-
[Objective]To evaluate the midterm clinical and radiographic results of revision hip arthroplasty by acetabular reinforcement ring (ARR) with impaction bone grafting. [Methods]Revision hip arthroplasty by ARR with impaction bone grafting of 8 hips was performed from May 2001 to December 2006. There were 5 males and 3 females with an average age of 53 years (range, 36~70 years).The mean BMI was 20 (range, 15~28). The mean interval between the primary arthroplasty and revision was 5 to 20 years (mean 6.7 years). The causes for revision were infective loosing in 2 and aseptic loosening in 6. In the 8 hips, 6 hips underwent a revision total hip arthroplasty, 2 hips received replacement of the acetabular component. Consecutive radiographs were compared to evaluate component conditions and the influence of bone deficiency to fix the prothesis was analyzed. Harris hip scores (HHSs) were determined before surgery and at the most recent follow-up examination. The Kaplan-Meier survivorship analysis was used to estimate the probability of survival of the prothesis.[Results]Seven hips were available for complete clinical and radiographic analysis. One patient died for myocardial infarction. The mean follow-up period was 4.5 years (range, 1.5~7.1 years).The mean preoperative Harris hip score of 30(range, 20~64) points improved to 88 (range, 74~94) points at the time of final follow-up, the pain and function socre improved from 13.8 and 11.5 to 40.3 and 39.9 respectively. All patients had severe limp before revision. At the time of final follow-up, 5 patients still had slight limp and 1 patients had moderate limp.Five hips had an excellent result. Infective osteolysis and migration were seen in 2 hips, which need re-revision. Heterotopic ossification developed in 2 hips . Kaplan-Meier survivorship at 4.5 years was 63% with repeat revision or radiographic loosening.[Conclusion]ARR with impaction bone grafting is an effective approach to treat massive acetabular bone defect in revision hip arthroplasty, the midterm result is acceptable, but any possible reason for infection must be monitored.
4.Biological characteristics of bone marrow mesenchymal stem cells and application in skin defect repair
Peng DU ; Xiaochuan WANG ; Zhen GUAN
Chinese Journal of Tissue Engineering Research 2016;20(50):7530-7535
BACKGROUND:An appropriate biomaterial can be directly combined with autologous or al ogeneic skin cel s to construct tissue-engineered skin, which can accelerate skin repair after transplantation onto the skin wounds. It is a good idea to solve the deficiency in skin sources. OBJECTIVE:To study the biological characteristics of the complex with bone marrow mesenchymal stem cel s and to investigate the application of this complex in skin defect repair. METHODS:Twenty-eight Sprague-Dawley rats, SPF grade, were randomized into two groups (n=14 per group). By adjustment of temperature, time, pressure and area of NC perm instrument, scald models were made in rats. Rats in the treatment group were given the repair using composite bone marrow mesenchymal stem cel s, while those in the control group were given vaseline gauze repair. Repair effects were compared between two groups. RESULTS AND CONCLUSION:(1) After 72 hours of culture, the composite bone marrow mesenchymal stem cel s smal with round shape distributed dispersedly. After 5 days of culture, the cel s began to stretch and the cel morphology became unstable. After three passages, the cel morphology became stable. The results of antigen identification showed the expression of CD44 and CD29 but the low expression of CD45 and CD34 in bone marrow mesenchymal stem cel s. (2) Twenty-eight days after repair, there was no obvious scar on the wound surface of the treatment group, but a little shrinkage and obvious scar stil existed in the control group. Moreover, in the control group, the epidermal layer of the skin was relatively thick, and the connection between the basal layer and the dermis was unsatisfactory. In the treatment group, obvious epidermal cel stratification, neat arrangement, and tight connection between the epidermis and dermis were observed. In summary, bone marrow mesenchymal stem cel s are a special class of cel s that have pluripotent ability and are more readily available. These cel s are the preferred target cel s for skin defect repair to promote early healing of the skin and improve blood circulation defect site, which are confirmed to have high clinical value.
5.The Differential Expression of p53,VEGF and MVD in Breast Cancer and Tumor Adjacent Tissues and Its Clinical Significance
Heping PENG ; Hao GUAN ; Helong XIAO
Journal of Chinese Physician 2001;0(10):-
Objective To detect the expressions of p53, vascular endothelial growth factor (VEGF) and microvessel density (MVD) in breast cancer and tumor adjacent tissues to explore their relationship and roles in the pathogenesis of breat cancer. Methods The expression levels of p53,VEGF and MVD were assessed in 110 cases of breast cancer and tumor adjacent tissues with SP immunohistochemical method. Results The positive expression rate of VEGF and p53 was 90.0%(99/110) and 42.7%(47/110) in the breast cancer tissues, and 35.5%(39/110) and 4.5%(5/110) in the tumor adjacent tissues, respectively, which had highly significant difference between two groups (P
6.Feasibility of ~1H-MRS in the DEN induced rat hepatocellular carcinoma by a new 1.5T MR scanner
Weidong ZHAO ; Sheng GUAN ; Weijun PENG
China Oncology 1998;0(04):-
Purpose:To study the feasibility of 1 H-magnetic resonance spectroscopy ( 1 H-MRS) in the chemical induced rat hepatocellular carcinoma(HCC) model by a new 1.5T MR set and endeavor to have an initial understanding of the characteristics of its cancer development. Methods:Diethylnitrosamine (DEN) induced rat HCC models(n=30) were established. At different intervals rats were randomly scanned before being killed on the following day. Their livers were dissected for histopathologic study. Results:Three rats died unexpectedly. 27 rats (90%) developed liver lesions and were investigated according to the plan. T 1 WI is good for demonstration of anatomic structure and T 2 WI at showing the lesions in detail. The scanning methods have been improved gradually. 1 H-MRS results were satisfactory for 64% of the single-voxel and 50% of the multi-voxel respectively. Conclusions:DEN induced rat HCC model is suitable for the Medical Imaging studies and liver 1 H-MRS scan is practical with this new 1.5T unit.
7.A quantitative study of neuroglobin in cerebral cortex after traumatic brain injury in rats
Xiangang DU ; Peng GUAN ; Xuemei CHEN
Chinese Journal of Forensic Medicine 1987;0(03):-
Objective The amount of neuroglobin(Ngb) in cerebral cortex after different post-traumatic time intervals were studied in order to find out the value of Ngb in estimating the survival time after trauma.Methods Moderate brain contusions in rats were made using free-falling-body impact device,The area and gray values of Ngb immunoreactive products(Ngb-IR)in the core of injury in cerebral cortex and penumbra and the contra lateral cerebral cortex at different time points after trauma were studied by immunohistochemical method and image analysis.Results The expression of Ngb in the core of injured cerebral cortex declined quickly and reached the nadir by 24 hours and remained at low level for long time.On the contrary,it rose quickly and reached the peak value at 12 hours in the penumbra surrounding the core of injury,then declined gradually and reached normal level at 8d to 16d.Image analysis revealed that the expression of Ngb-IR in the penumbra of injured cortex were stronger than that in the opposite side.Conclusion The amount of Ngb in cerebral cortex at the core and penumbra of injury changed regularly according to different time intervals after trauma.Ngb may play an important role in neuroprotection during acute phase of injury.
8.Effect of preemptive analgesia of katamine and clonidine on postoperative pain and stress response
Yingjun GUAN ; Ke PENG ; Zhenshan YAN
Chinese Journal of Primary Medicine and Pharmacy 2009;16(1):16-17
Objective To observe the preemptive analgesia effects of katamine and elonidine, and to find out the influence of preemptive on stress responses. Methods 36 patients with hysteromyoma undergone hysteromyomec-tomy were randomly assigned to three groups (n = 12 each group) :group Ⅰ , control group, without preemptive analge-sia,the patients in control group were given continous epidural analgesia with 2% lidoeaine 12 - 14ml. Group Ⅱ ,the patients were injected 0. 6mg/kg katamine into epidural analgesia 30 minutes before operation. Group Ⅲ,the patients were injected 0. 6mg/kg katamine and 1.5μg/kg clonidine into epidural analgesia 30 minutes before operation. The patients in three groups were recorded VAS score on 2h ,4h ,6h, 12h ,24h after operation, also recorded the change of epinephrine(E) and norepinephrine(NE) and sensation and movement recovery time after operation. The side effects such as dizziness nausea,vomit,and exited talking were observed during the operation. Results The VAS score were significantly different between group Ⅰ ,Ⅱ and Ⅲ. The levels of E and NE in plasma in group Ⅰ were increased more than group Ⅱ and Ⅲ within 24 hours after operation, also there is significant difference in group Ⅱ compared with group Ⅲ in T1 ,T2 ,T3. The time of sensation and movement recovery were remarkably longer in group Ⅲ com-pared with group Ⅰ and Ⅱ, showing significant difference. There were no significant difference in side effects after operation in three groups. Conclusion The preemptive analgesia of kutamine and colnidine can relieve the pain of lower abdominal surgery and stress response after operation,and it do not increase the side effects.
9.Advances ion chitosan sustained-release microspheres containing fluoroquinolones
Peng CHENG ; Jing GUAN ; Hua ZHANG
International Journal of Biomedical Engineering 2009;32(6):344-347,352
Chitosan microsphere containing fluoroquinolones is a kind of novel sustained-released antibacterial agent that possesses the antibacterial and bacteriostatic property of chitosan as well as bactericidal properties of fluoroquinolones. Loading fluoroquinolones in the chitosan microsphere can greatly enhance its antibacterial, bactericidal, anti-inflammation and anti-infection characteristics. This paper reviewes the recent study on different preparation methods of chitosan mierosphere containing fluoroqninolones and discusses its applications.
10.THE SICK SINUS SYNDROME A CASE REPORT
Bingkang WANG ; Peng GUAN ; Shicang LIU ;
Chinese Journal of Forensic Medicine 1987;0(03):-
A case of the Sick Sinus Syndrome which was based on the diagnosis ofautopsy is reported in this paper.It was found that a decreased number ofpacemaker cells with fibrosis,fatty infiltration and the thick endothelium ofcenter arteriole in sinus-atrial node.Otherwise the vacuolar degenerationcould be seen in the bundle of his.There were no fetal pathological changesto be seen in other organs.