Materials and techniques currently used for bone replacement/repair conform to the current paradigm, relying on bone or bone products to produce bone or induce bone formation. Yet, nature forms and heals most of the skeleton by ossification of a cartilaginous model. In this study, we cultured aggregates of E10.5 or E12 mouse embryonic limb cells in the bioreactor for 3 weeks, determined the stages of cartilage differentiation attained, and assessed the ossification and bone healing potential of the spheroids by implantation adjacent to, or directly in, a skull defect. Cultured spheroids had large cartilaginous areas, sometimes with cellular arrangements characteristic of growth plate zones. Aggregates implanted for 2 weeks adjacent to a defect mineralized and ossified (histology, micro-CT). Defects with implants had a central mass of differentiated and differentiating bone, with osteoclast activity, filling the defect. Controls had considerable remodeling on the bone edges demarcating the still present defect. This study shows that cartilage, grown in the bioreactor for 3 weeks, ossified when implanted adjacent to a bone defect, and when implanted directly in a defect, contributed to its healing. Our ability to grow differentiated bone-forming cartilage for implantation is an alternative approach in the field of bone repair.

The important issues to be emphasized when considering the intrathecal administration of novel analgesics are their proven antinociceptive effect, safety (short- and long-term effects on the spinal cord and potential toxicities), stability in shelf solution and at body temperature by itself, or in combination with other drugs in spinal fluid, compatibility with a long-term spinal infusion pump, whether they are of sufficiently high potency and solubility to be used in the finite volume of an implanted infusion pump, and if a pharmaceutical company is willing to invest the immense resources needed for US Food and Drug Administration approval and subsequent commercial development.

No abstract

Anatomical studies of the vasculature of the eye have been reported in a variety of animals. However, published reports of comparative studies are few in number and there are fewer yet published reports on the long posterior ciliary artery (LPCA). The present study focuses on the organization and structure of the LPCA and its branches in three different species. Our study of the vasculature of the eye was performed utilizing methacrylate vascular casting and observation by light microscopy and scanning electron microscopy. The study was designed to elucidate the anatomical formation of the long posterior ciliary artery and its branches and how this system differed in rabbits, cats and rats. Our findings showed that each species had a characteristic vascular pattern. In the rabbit eye, the LPCA supplied the anterior segment, the choroid, and was considered the only arterial supply of the uvea. In cat eyes, the choroid was supplied by many short posterior ciliary arteries (SPCAs) that arose from the ophthalmic artery.