Dental pulp stem cells (DPSCs) are shown to reside within the tooth and play an important role in dentin regeneration. DPSCs were first isolated and characterized from human teeth and most studies have focused on using this adult stem cell for clinical applications. However, mouse DPSCs have not been well characterized and their origin(s) have not yet been elucidated. Herein we examined if murine DPSCs are neural crest derived and determined their in vitro and in vivo capacity. DPSCs from neonatal murine tooth pulp expressed embryonic stem cell and neural crest related genes, but lacked expression of mesodermal genes. Cells isolated from the Wnt1-Cre/R26R-LacZ model, a reporter of neural crest-derived tissues, indicated that DPSCs were Wnt1-marked and therefore of neural crest origin. Clonal DPSCs showed multi-differentiation in neural crest lineage for odontoblasts, chondrocytes, adipocytes, neurons, and smooth muscles. Following in vivo subcutaneous transplantation with hydroxyapatite/tricalcium phosphate, based on tissue/cell morphology and specific antibody staining, the clones differentiated into odontoblast-like cells and produced dentin-like structure. Conversely, bone marrow stromal cells (BMSCs) gave rise to osteoblast-like cells and generated bone-like structure. Interestingly, the capillary distribution in the DPSC transplants showed close proximity to odontoblasts whereas in the BMSC transplants bone condensations were distant to capillaries resembling dentinogenesis in the former vs. osteogenesis in the latter. Thus we demonstrate the existence of neural crest-derived DPSCs with differentiation capacity into cranial mesenchymal tissues and other neural crest-derived tissues. In turn, DPSCs hold promise as a source for regenerating cranial mesenchyme and other neural crest derived tissues.

Context.-Each laboratory should have criteria for manual smear review that limit workload without affecting patient care. The International Consensus Group for Hematology Review established guidelines for action after automated blood cell analysis in 2005.Objective.-To compare the consensus group criteria with our laboratory criteria and optimize them for better efficiency.Design.-A total of 2114 first-time samples were collected consecutively from daily workload and were used to compare 2 criteria as well as establish the optimized criteria. Another set of 891 samples was used to validate the optimized criteria. All samples were run on either Sysmex XE-5000 or Coulter LH750 hematology analyzers and were investigated by manual smear review. The efficiency of each set of criteria was compared and optimized to obtain better efficiency, an acceptable review rate, and a low false-negative rate.Results.-From 2114 samples, 368 (17.40%) had positive smear results. Compared with that of our laboratory criteria, the efficiency of the consensus group criteria was higher (83.63% versus 78.86%, P , .001), the review rate was higher (29.33% versus 22.37%, P , .001), and the false-negative rate was lower (2.22% versus 8.09%, P , .001). After optimizing the rules, we obtained an efficiency of 87.13%, a review rate of 24.22%, and a false-negative rate of 2.98%. We validated the optimized criteria with another set of samples, and the efficiency, review rate, and false-negative rate were 87.32%, 25.25%, and 1.12%, respectively.Conclusions.-Each laboratory should verify the criteria for smear review, based on the International Consensus Group for Hematology Review, and optimize them to maximize efficiency.

BackgroundThere are few data focusing on the prevalence of vitamin D deficiency in tropical countries. ObjectivesWe determined the vitamin D status in pregnant women and examined the factors associated with vitamin D deficiency. Design and MethodsA cross-sectional study of 147 pregnant Thai women aged 18–45 years at Siriraj Hospital (a university hospital in Bangkok, Thailand) was undertaken. Clinical data and plasma levels of 25-hydroxyvitamin D [25(OH)D], intact parathyroid hormone (iPTH), calcium, albumin, phosphate and magnesium were obtained in pregnant women at delivery. ResultsThe prevalence of hypovitaminosis D [defined as 25(OH)D <75 nmol/L] in pregnant women at delivery was 75.5% (95% confidence interval (CI), 67.7–82.2%). Of these, vitamin D insufficiency [defined as 25(OH)D 50–74.9 nmol/L] was found in 41.5% (95% CI, 33.4–49.9%) and vitamin D deficiency [25(OH)D <50 nmol/L] was found in 34.0% (95% CI, 26.4–42.3%) of women. The mean 25(OH)D concentration was 61.6±19.3 nmol/L. The correlation between 25(OH)D and iPTH was weak (r = –0.29, P<0.01). Factors associated with vitamin D deficiency by multiple logistic regression were: pre-pregnancy body mass index (BMI in kg/m2, odds ratio (OR), 0.88, 95% CI 0.80–0.97, P = 0.01) and season of blood collection (winter vs. rainy, OR, 2.62, 95% CI 1.18–5.85, P = 0.02). ConclusionsVitamin D deficiency is common among pregnant Thai women. The prevalence of vitamin D deficiency increased in women who had a lower pre-pregnancy BMI and whose blood was collected in the winter. Vitamin D supplementation may need to be implemented as routine antenatal care.