Although bone morphogenic protein (BMP)-2 is known to potently induce osteogenic differentiation of human mesenchymal stem cells, strong individual differences have been reported. In part, this is due to internal antagonists of BMP-2 for example, noggin and chordin, secreted by differentiating cells. This enabling study was performed to prove the hypothesis that osteogenic effects of BMP-2 can be improved by transient nonviral gene silencing of chordin. We investigated the effect of siRNA against chordin on osteogenic differentiation in human adipose tissue-derived stromal cells (hASC). Cells of two different donors were isolated after liposuction and proliferated for passage 4 or 5. On seeding, hASCs were transfected with siRNA using a commercial liposomal transfection reagent. Subsequently, cells were differentiated in the presence or absence of BMP-2 (100 ng/mL). Noncoding siRNA as well as siRNA against noggin served as a control. Osteogenic differentiation of hASC was determined by alkaline phosphase (ALP) activity and matrix mineralization. ALP activity of hASC treated with siRNA against chordin was increased for cells of both donors. In contrast, silencing of noggin had no effect in any of the donors. In combination with BMP-2, silencing of either chordin or noggin showed strongly improved ALP activity compared with the control group that was also supplemented with BMP-2. Mineralization was observed to start earlier in groups that received siRNA against chordin or noggin and showed increased amounts of incorporated calcium on day 15 compared with the control groups. Silencing chordin in hASCs was successful to increase BMP-2 effects on osteogenic differentiation in both donors, while effects of noggin silencing were reliably observed only in one of the two investigated donors. In contrast to noggin silencing, chordin silencing also increased osteogenic differentiation without supplemented BMP-2.

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Background: Mesenchymal stem cells (MSCs) have great promise in the field of regenerative medicine due to their differentiation potential into several lineages. Besides the bone marrow, MSCs can be obtained from the dermis, which represents a large stem cell reservoir in the skin. Sheep provide an appropriate large animal model for preclinical studies. In this study, we focused on the isolation and characterization of MSCs from sheep dermis as an alternative to bone marrow MSCs (bmMSCs). Methods: Primary ovine cells were obtained from the dermis for comparison with bone marrow. CD271⁺/45^- dermal MSCs (CD271-dMSCs), which were sorted by flow cytometry, and plastic-adherent bmMSCs were examined for morphology, proliferation and senescence-associated β-galactosidase activity in both low and high oxygen conditions. CD271 expression on cultured cells was assessed by flow cytometry. Adipogenic and osteogenic potentials of CD271-dMSCs were evaluated by oil red O and von Kossa staining. Chondrogenic capacity of CD271-dMSCs and CD271⁺/CD45^- bone marrow cells (CD271-bmMSCs) was detected using immunohistochemistry and measurement of sulfated glycosaminoglycans. Results: The cell proliferation assay demonstrated no significant difference between CD271-dMSCs and bmMSCs under low oxygen conditions. Cultured CD271-dMSCs revealed much more CD271 expression compared to CD271-bmMSCs. CD271-dMSCs and CD271-bmMSCs showed basically similar expression of the cartilage-specific proteins aggrecan and collagen type II, although with a stronger staining in CD271-bmMSC-derived cultures. Remarkably, there was co-expression of CD271 and aggrecan during chondrogenic differentiation, suggesting an involvement of CD271 in chondrogenesis. Conclusion: Based on these findings, CD271-dMSCs might serve as an appropriate alternative cell source in preclinical research.

Cigarette smoke has been documented to be related to the development of cancer. However, the exact mechanism for the carcinogenic action of cigarette smoke is still unknown. Nicotine is recognized to be the major compound in cigarette smoke and has been suggested to play a role in oral cancer via a cyclooxygenase (COX)/ prostaglandin-dependent pathway. This study was designed to evaluate the action of nicotine in the oral cancer cell and to further examine whether COX-2 is responsible for expression of tumor-associated angiogenic vascular endothelial growth factor (VEGF) in vitro. Viability of human oral squamous cancer cells (BHY) was measured using MTT assay. Protein expression was determined by Western blot and immunoassay kits. We found that exposure of BHY cells to nicotine (200 µg/mL for 6 hours) resulted in 2.9-fold induction of COX-2 expression as well as a 4-fold increase in VEGF levels compared with a control group. Pretreatment with celecoxib inhibited nicotine-induced change in the expression of VEGF and COX-2. The results suggest that stimulation of COX-2 and VEGF expression can contribute as important factors in the tumorigenic action of nicotine in oral cancer progression. This effect can be blocked by celecoxib, suggesting an interaction of nicotine and COX-2 pathways.

Abstract-Medication errors are the most common type of medical errors in health-care domain. The use of electronic prescribing systems (e-prescribing) have resulted in significant reductions in such errors. However, dealing with the heterogeneity of available information sources is still one of the main challenges of e-prescription systems. There already exists different sources of information addressing different aspects of pharmaceutical research (e.g. chemical, pharmacological and pharmaceutical drug data, clinical trials, approved prescription drugs, drugs activity against drug targets. etc.). Handling these dynamic pieces of information within current e-prescription systems without bridging the existing pharmaceutical information islands is a cumbersome task. In this paper we present semantic medical prescriptions which are intelligent e-prescription documents enriched by dynamic drug-related meta-data thereby know about their content and the possible interactions. Semantic prescriptions provide an interoperable interface which helps patients, physicians, pharmacists, researchers, pharmaceutical and insurance companies to collaboratively improve the quality of pharmaceutical services by facilitating the process of shared decision making. In order to showcase the applicability of semantic prescriptions we present an application called Pharmer. Pharmer employs datasets such as DBpedia, DrugBank, DailyMed and RxNorm to automatically detect the drugs in the prescriptions and to collect multidimensional data on them. We evaluate the feasibility of the Pharmer by conducting a usability evaluation and report on the quantitative and qualitative results of our survey.