Stereocontrolled Semisyntheses of Elliptone and 12aß-Hydroxyelliptone.

Operationally simple, stereocontrolled semisyntheses of the anticancer rotenoids elliptone and 12aß-hydroxyelliptone, isolated from Derris elliptica and Derris trifoliata, respectively, are described. Inspired by the work of Singhal, elliptone was prepared from rotenone via a dihydroxylation-oxidative cleavage, chemoselective Baeyer-Villiger oxidation, and acid-catalyzed elimination sequence. Elaboration of elliptone to 12aß-hydroxyelliptone was achieved via a diastereoselective chromium-mediated Étard-like hydroxylation. The semisynthesis of elliptone constitutes an improvement over previous methods in terms of safety, scalability, and yield, while the first synthesis of 12aß-hydroxyelliptone is also described.

The relationship between degree of facet tropism and amount of dynamic disc bulge in lumbar spine of patients symptomatic for low back pain.

Facet tropism has been investigated as a predisposing factor for degenerative changes in the lumbar spine; however, no prior study has evaluated the relationship between disc bulge and facet tropism. In this study, we used kinetic magnetic resonance imaging (kMRI) to investigate the association between degree of facet tropism and amount of disc bulge in the lumbar spine in relation to age. kMRIs in the flexion, neutral, and extension positions were performed on 410 consecutive patients with low back pain. T2-weighted midsagittal and axial mid-disc cuts were analyzed to measure disc bulge and facet angle. Facet asymmetry was calculated and classified as: no facet tropism, <6°; mild facet tropism, 6-11°; or severe facet tropism, ≥11°. Maximal static bulge (MSB), maximal dynamic bulge (MDB), and age in the facet tropism groups were compared by age subpopulations and MDB categories, defined by the positions between which the largest change in disc bulge occurs. We found the severe facet tropism group to be associated with a nearly significant increase in MSB and MDB over the no facet tropism group in the older subpopulation at the L4-L5 level only, and a larger MDB in the L4-L5 MDB category [E-N], where the greatest change in disc bulge occurs between neutral and extension positions (p = 0.013). Our findings suggest that severe facet tropism is associated with increased disc bulge at L4-L5 in only a subset of older age patients, but may in large part be due to biomechanical factors that define the [E-N] category.

The treatment of unstable ankle fractures in patients over eighty years of age.

BACKGROUND: The current study examined the outcomes of operative treatment of unstable ankle fractures in patients at least 80 years old at the time of injury. METHODS: Of 2,682 patients who presented for treatment of ankle fractures, 17 patients met the study criteria. These patients had open reduction and internal fixation after sustaining 15 closed and two open unstable ankle fractures. There were 11 type B fractures and six type C fractures by the Danis-Weber classification, and 12 supination-external rotation and five pronation-external rotation fractures by the Laugen-Hansen classification systems. RESULTS: When noncompliant patients who developed complications were removed from analysis, the fixation failure and deep infection rates were 0% each. CONCLUSIONS: These results highlight the importance of patient compliance and non-weightbearing status in the treatment of ankle fractures in patients over 80 years.

Can bone morphogenetic protein binding peptide increase efficiency of bone formation?

STUDY DESIGN: The role of bone morphogenetic protein binding peptide (BBP) in bone formation is reviewed from basic science studies and potential clinical application. OBJECTIVE: We review the discovery and early scientific studies of BBP with emphasis on potential future clinical applications. SUMMARY OF BACKGROUND DATA: Biologics delivered locally to enhance bone formation are of increasing importance, particularly in spinal fusion. The most useful agents currently available are bone morphogenetic proteins (BMPs). The indications for recombinant human BMP are expanding; however, certain disadvantages including high costs, unwanted ectopic bone formation, and local inflammatory reaction are becoming more prevalent. As a result, alternate strategies are being developed to provide safer, less expensive, and more efficacious adjuvant agents. METHODS: This study reviews the existing published data and early experimental results, and explores potential clinical applications of BBP. RESULTS: BBP is a specific binding protein for BMP with an intermediate affinity, which makes it an ideal "slow release" agent. CONCLUSION: BBP may reduce the time to fusion and more thoroughly control the distribution of bone healing in spinal fusion. Further study is ongoing to explore clinical applications.