P A Rust | PubMed Health

PubMed2007

Will mesenchymal stem cells differentiate into osteoblasts on allograft?

Tissue engineering approaches for bone blocks previously have used synthetic scaffolds. Bone graft (allograft) is used to fill bone defects, but standard processing can lessen this scaffold's osteoinductive potential. We wanted to test if allografts could be used to produce a viable bone block using mesenchymal stem cells. We hypothesized that mesenchymal stem cells differentiate into osteoblasts producing extracellular matrix when cultured on allografts. We also hypothesized that the addition of osteogenic supplements would increase the rate of differentiation. To test these hypotheses, mesenchymal stem cells were isolated from bone marrow aspirated from 10 patients and cultured on allografts from five donors (Group 2), producing 50 samples. This was repeated on allografts heat-treated to denature bioactive proteins (Group 1), and repeated again on allografts to which osteogenic supplements (Group 3) were added. Group 2 mesenchymal stem cells differentiated into osteoblasts producing higher levels of alkaline phosphatase, osteopontin, and Type I collagen matrix protein than Group 1. The rate of differentiation of Group 3 mesenchymal stem cells increased with the supplements. Overall, it was established that the bioactive proteins in the allograft stimulated mesenchymal stem cell differentiation into osteoblasts, with production of extracellular matrix, and that this differentiation increased with the addition of osteogenic supplements.

Alkaline Phosphatase↗

PubMed2001

Alcohol and radiographs in the accident and emergency department.

OBJECTIVE: To investigate the contribution of alcohol ingestion to the radiological workload of an inner city accident and emergency (A&E) department. METHODS: A prospective survey of patients presenting to A&E who required radiographs was performed over a seven day period. The A&E clinician questioned patients about alcohol intake during the six hours before the onset of the presenting complaint or injury, and made an objective assessment of signs of alcohol ingestion or intoxication. An assessment was made also of the relative contribution of alcohol as a cause of patients' injuries. RESULTS: A total of 419 patients who had radiography fulfilled the inclusion criteria, and a questionnaire was completed for 351 (84%). Forty (11%) of 351 were found to have ingested alcohol. Thirty five (87%) of 40 patients who had ingested alcohol were radiographed for trauma, as compared with 171 (55%) of the 311 who had not (p<0.001). Alcohol was considered to have been causative of injury in 30% and a contributory factor in an additional 58%. Radiographs of the skull, face and jaw accounted for 18 (33%) of 55 radiographs from trauma patients who had ingested alcohol compared with 20 (9%) of 212 radiographs from those who had not (p<0.001). There was no significant difference in the proportion of abnormal radiographs between these two groups (27% of radiographs from trauma patients who had ingested alcohol compared with 23% of radiographs from those who had not, p>0.2). CONCLUSION: Patients with alcohol related injuries requiring radiography have a significant impact on the radiological workload of an A&E department, although the prevalence of alcohol ingestion detected in this study was less than expected from previous studies.

Adult↗