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.

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.

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.

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.

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

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.

Objective To systematically assess the relationship between oral administration of aspirin and survival benefit for patients with colorec?tal cancer(CRC)by meta?analysis. Methods Relevant studies were identified through searching PubMed and EMBASE. Random?effects model was derived to composite the pooled hazard ratio for overall mortality and CRC?specific mortality. The subgroup analysis was conducted for included data,and the bias analysis was reported. Results Thirteen studies on aspirin therapy were finally included in this meta?analysis. The overall surviv?al benefit associated with oral administration of aspirin represented an HR of 0.83(95%CI:0.71?0.96). Oral administration of aspirin was also asso?ciated with CRC?specific survival(HR=0.77,95%CI:0.64?0.93). No evidence was observed of an association between prediagnostic aspirin use and CRC overall survival(HR=1.00,95%CI:0.85?1.18)or CRC?specific survival(HR=0.97,95%CI:0.83?1.13). Conclusion These findings provide further indication that post?diagnostic aspirin therapy can improve CRC prognosis.

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.

[Objective]To investigate the outcomes of cementless metasul metal-on-metal total hip arthroplasty.[Method]Metasul metal-on-metal total hip arthroplasty of 30 hips in 25 patients was performed from August 2003 to December 2005.There were 11 males and 14 females with an average age of 47 years(28-72 years).Harris hip scores were determined before surgery and at the last follow-up examination.Standardized radiographs were obtained to evaluate component conditions.Blood samples were taken to determine serum chromium levels with use of atomic absorption spectrometry.[Result]Twenty-three patients(28 hips)were followed up with a mean period of 3.6 years(2.5-4.8 years).The mean Harris hip score improved from 49.5(17-78)points preoperatively to 93.4(55-99)points at the time of final follow-up.Twenty-two hips(85%)had an excellent result.Radiolucent lines were found in 3 hips.Focal femoral osteolysis was seen only in one patient.Sciatic nerve was injured in one case,which showed rehabilitation after 2.5 years.One hip had periprothetic infection because of diabetes 4 years after operation.There was no measurable wear by X-rays.No dislocation or fracture was found.The median serum chromium concentration was 0.082 ?g/mL(0.020～0.140 ?g/mL).No patient was diagnosed with renal insufficiency or hematologic malignancy during the study period.[Conclusion]The outcomes of Metasul metal-on-metal total hip arthroplasty are satisfactory.However,additional follow-up is necessary to determine any possible long-term deleterious effects.

[Objective]To discuss the cementless revision for postoperative infection after hip arthroplasty.[Methods]From November 1997 to December 2006,7 patients(7 hips) with infection after hip arthroplasty were treated,including 3 males and 4 females,with a mean age of 58 years(36～73 years).In the 7 hips,4 hips underwent a revision of total hip arthroplasty,2 hips only received new acetabular components and 1 hip underwent stem revision.One-stage revision was performed in 4 cases,two-stage revision was performed in 3 cases.Consecutive radiographs were compared to evaluate component conditions.Harris hip scores were determined before surgery and at the final follow-up examination.The erythrocyte sedimentation rate and C-reactive protein were detected.[Results]All patients were followed up with a mean period of 3.6 years(1.5～10.6 years).The mean Harris hip score improved from 35(18-63) points preoperatively to 89(60～99) points at the time of final follow-up.No re-infection was found.Femoral component exsertion was found in 1 patient but without any symptom.Pain of hip joint disappeared in 5 cases,and 2 patients had mild pain when walking long distance.At the time of final follow-up,5 patients still had slight limp.Heterotopic ossification developed in 1 hip.The mean polyethylene liner wear was 0.08 mm per year at final follow-up.Deep vein phlebothrombosis and nerve injury were not found.[Conclusion]It is possible to have satisfactory clinical outcome by one-stage or two-stage revision using cementless prothesis for postoperative infection after total hip arthroplasty.Whether the original prothesis can be saved when fixed tightly with femur or acetabular bone needs more experiences to confirm.