Low-Symmetry ß-Diketimine Aryloxide Rare-Earth Complexes: Flexible, Reactive, and Selective.

We report the synthesis, characterization, and reactivity of a new low-symmetry ß-diketimine featuring a pendant amino(methyl)phenol donor and its corresponding heteroleptic rare-earth (RE) complexes. This includes the first structurally characterized examples of alcoholysis and insertion from an isolated REIII amide in a ß-diketimine framework. The flexible methylene linkage leads to REIII complexes with tunable dynamic solution behavior that defines their stoichiometric and catalytic reactivity. The addition of a strong neutral donor ligand, tricyclohexylphosphine oxide, suppresses a prevalent catalyst degradation pathway (base-promoted elimination) and dramatically enhances the catalyst performance in the stereospecific ring-opening polymerization of rac-ß-butyrolactone. Our results further demonstrate the importance of ligand reorganization in the stoichiometric and catalytic activity of REIII ions.

A National Assessment of the Association Between Patient Race and Physician Visit Time During New Outpatient Urology Consultations.

OBJECTIVE: To determine if there is an association between patient race and physician time spent with the patient during outpatient urology consultations. METHODS: We identified all adult urology new outpatient visits in the National Ambulatory Medical Care Survey dataset for 2012-2016. Patient race was dichotomized as White or non-White. Our primary outcome was time spent during the visit between the patient and urologist. Using population-level weighting, we compared differences in mean time spent during visits with White and non-White patients. Mixed-effects linear regression was used to adjust for confounding factors and to account for clustering among individual physicians. Secondary outcomes included number of services provided and if ancillary providers were seen. RESULTS: Over the 5 year period, 1668 raw visits met criteria and were used to estimate 21million new outpatient urology visits nationwide. 80% of all visits were with White patients. Mean physician time spent among visits with white patients was 23.9 minutes and 24.4 minutes for non-White patients. There was no difference in number of services provided but visits with non-white patients were less likely to include an ancillary provider. After adjustment, there was no significant difference in mean time spent with the urologist among visits with White and non-White patients (difference 0.9 minutes, 95% CI: -0.6-2.4). There were also no differences in adjusted mean time spent among return visits or new visits for hematuria, urologic cancers, or BPH. CONCLUSION: We found no statistically significant difference in time spent with a urologist during outpatient office consultations between White and non-White patients.

Bone Graft Options in Spinal Fusion: A Review of Current Options and the Use of Mesenchymal Cellular Bone Matrices.

BACKGROUND: Spinal fusion is the mainstay treatment for various spinal conditions ranging from lumbar and cervical stenosis to degenerative spondylolisthesis as well as extensive deformity corrections. A new emerging category of allograft is cellular bone matrices (CBMs), which take allogeneic mesenchymal stem cells and incorporate them into an osteoconductive and osteoinductive matrix. This study reviewed the current spinal fusion options and new emerging treatment options. METHODS: Articles were searched using PubMed. The search included English publications since January 1, 2014, using the search terms "cellular bone matrix," "mesenchymal stem cells spinal fusion," "spinal arthrodesis AND mesenchymal stem cells," and "spine fusion AND cellular bone matrix." RESULTS: Spinal fusion is accomplished through the use of allografts, autografts, and bone graft substitutes in combination or alone. An emerging category of allograft is CBMs, in which an osteoconductive and osteoinductive matrix is filled with mesenchymal stem cells. Studies demonstrate that CBMs have achieved equivalent or better fusion rates compared with traditional options for anterior cervical discectomy and fusions and posterolateral lumbar fusions; however, the studies have been retrospective and lacking control groups and therefore not ideal. CONCLUSIONS: Many treatment options have been successfully used in spinal fusion. Newer allografts such as CBMs have shown promising results in both animal and clinical studies. Further research is needed to determine the therapeutic dose of mesenchymal stem cells delivered within CBMs.