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Vascularization of engineered bone tissue is critical for ensuring its survival after implantation and it is the primary factor limiting its clinical use. A promising approach is to prevascularize bone grafts in vitro using endothelial progenitor cells (EPC) derived from peripheral blood. Typically, EPC are added together with mesenchymal stem cells (MSC) that differentiate into osteoblasts. One problem with this approach is how to promote traditional tissue engineering bone survival with a minimally invasive method. In this study, we examined the effectiveness of administering to stimulate the release of peripheral blood stem cells and their co-culturing system for generating prevascularized engineered bone. Cells were isolated by Ficoll density gradient centrifugation and identified as EPC and MSC based on morphology, surface markers, and functional analysis. EPC and MSC were cocultured in several different ratios, and cell morphology and tube formation were assessed by microscopy. Expression of osteogenesis and vascularization markers was quantified by enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction, and histochemical and immunofluorescence staining. Increasing the proportion of EPC in the coculture system led to greater tube formation and greater expression of the endothelial cell marker CD31. An EPC:MSC ratio of 75:25 gave the highest expression of osteogenesis and angiogenesis markers. Cocultures adhered to a three-dimensional scaffold of strontium-doped calcium polyphosphate and proliferated well. Our findings show that coculturing peripheral blood-derived EPC and MSC may prove useful for generating prevascularized bone tissue for clinical use.

NPWT can significantly reduce the risk of infection in treatment of open fractures and accelerate their wound healing process. Some but not much evidence suggests that NPWT may possibly help reduce the severity of the limb injury and therefore provide a chance for the limb to avoid amputation. Use of NPWT in the flap area is probably safe, but should be carried out with caution. The advantage of NPWT over the conventional wound dressings still requires to be confirmed in the other aspects.

AimsThe aim of the study was to explore the prevalence and clinical characteristics of hand ulcer in hospitalized patients with diabetes.MethodsWe analysed 17 subjects with hand ulcer among diabetic inpatients, who were admitted to the Diabetic Foot Care Center, Department of Endocrinology and Metabolism at the West China Hospital of Sichuan University from April 2003 to December 2008.ResultsThe prevalence of diabetic hand ulcer among hospitalized patients (0.37%) was significantly lower than that of diabetic foot ulcers (9.7%, P= 0.000). The mean age was 62.1 ± 9.4 years. The average known durations of diabetes and glycated haemoglobin (HbA1c) were 5.3 ± 4.9 years and 10.9 ± 2.4%, respectively. All patients lived in the subtropical zone. Fifteen patients (88.2%) were diagnosed with diabetic peripheral neuropathy. Ten patients had hand infection. After therapy, the ulcers healed in 13 patients (76.5%) and none of them experienced amputation. The average hospital stay for patients with local infection was characteristically longer than that for patients without infection (P= 0.012). The prognosis of the hand ulcer was poorer in the patients who had diabetes for > 3 years compared with those who had diabetes for < 3 years (P= 0.009).ConclusionsDiabetic hand ulcer is a relatively rare complication of diabetes in South-West China. Long duration of diabetes, poorly controlled blood glucose, minor trauma and delayed treatment are the risk factors. Diabetic peripheral neuropathy may play an important role in the pathogenesis of hand ulcer. Early control of blood glucose with insulin and early anti-microbial therapy with appropriate antibiotics are crucial. Debridement and drainage are necessary for hand abscesses.

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