PubMed · 14447423
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
1961. Bone sodium.. https://doi.org/10.1111/j.1753-4887.1961.tb01943.x
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Numerous reports have highlighted the use of mesenchymal stem cells (MSC) for tissue engineering because of the capacity of the cells to differentiate along the osteogenic, chondrogenic or adipogenic pathway. As MSC also display neuronal morphologies under appropriate culture conditions, the differentiation capacity of stem cells seems to be more complex than initially thought, but it requires careful characterization of the cells. This is especially the case because recently it has been suggested that neuronal differentiation of stem cells is only an artifact. Here, we investigate the sequence of ultrastructural changes of bone-derived stem cells during neuronal induction and compare these data with immunocytochemical and electrophysiological properties of the cells. For further comparative analyses, stem cells were incubated with non-neurologically inducing stressors. The stem cells were harvested from human osseous debris and were characterized morphologically, immunocytochemically and by using FACS. After 6 h of neuronal induction, the cells had assumed neuronal morphologies and expressed neuron-specific enolase, beta-III-tubulin, neurofilament-H and HNK-1, while only a subpopulation expressed CD15 and synaptophysin. However, electrical signaling could not be detected, neither spontaneously nor after electrical stimulation. Nevertheless, transmission electron microscopy revealed cellular features of neuritogenesis and synaptogenesis in the course of neuronal induction and suggested that the cells have features similar to those observed in immature neurons. Based upon the results, it can be concluded that neuronal induction had initiated the early steps of neuronal differentiation, while exposure of the cells to non-neurological stressors had caused necrotic alterations.
Recent investigations of human skeletal material from the historic St. Martin's cemetery, England, found a range of abnormal lesions in six infants that are almost certainly related to scurvy. Porous and proliferative bone lesions affecting the cranial bones and scapulae were found, and this paper presents images obtained using both macroscopic and scanning electron microscope examination of the lesions. Previous work on infantile scurvy (Ortner et al., 1997-2001) relied heavily on changes at the sphenoid, which is often missing in archaeological bone, so the identification of changes attributable to scurvy on other cranial bones and the scapulae is encouraging. The ability to recognize changes related to scurvy on a range of bones will ensure an enhanced potential for recognition of this disease in future research involving archaeological bone. Research on historical documents from Birmingham dating to the eighteenth and nineteenth centuries, combined with the probable cases of scurvy identified, supports the view that the paucity of cases of infantile scurvy from the archaeological record reflects a lack of understanding and recognition of bone manifestations, rather than a lack of occurrence in this period. Changes linked to scurvy were only found in infants from the poorer sections of the community from St. Martin's, and this is almost certainly linked to patterns of food consumption and may be related to shortages of potatoes, due to blight, experienced during this period.
Gross and radiographic changes characteristic of inadequate bone mineralization due to rickets are described in 21 immature skeletons from a 19th century urban population from Birmingham, England. The aims of the study are as follows: to evaluate and if possible augment existing dry-bone criteria for the recognition of rickets in immature skeletal remains; to investigate the value of radiography for the paleopathological diagnosis of rickets; and to compare and contrast the expression of rickets in this group with that previously documented for a rural agrarian population from Wharram Percy, England. Some gross skeletal signs of rickets which were not previously well-documented in paleopathological studies are noted. The worth of radiography for evaluating structural changes to both cortical and trabecular bone in the disease is demonstrated, and features useful for the interpretation of vitamin D deficiency are discussed. The pattern of skeletal elements affected and the severity of changes differs in the Birmingham group from that seen in the comparative rural population. It is emphasized that a variety of factors may influence the expression of rickets in paleopathological material, including rate of skeletal growth, age cohort affected, and intensity of vitamin D deficiency. Nevertheless, careful analysis, not only of the frequency of rickets but also of the degree of severity of lesions and the patterning with respect to skeletal elements affected, may enable more nuanced understanding of the biocultural context of the disease in earlier populations.