Orthopaedic surgeons continue to search for cost-effective bone graft substitutes to enhance bone repair. Teriparatide (PTH 1-34) and demineralized bone matrix (DBM) have been used in patients to promote bone healing. We evaluated the efficacy of PTH and DBM in healing a critical sized femoral defect in three lineage-specific transgenic mice expressing Col3.6GFPtopaz (preosteoblastic marker), Col2.3GFPemerald (osteoblastic marker) and a-SMA-Cherry (pericyte/myofibroblast marker). Mid-diaphyseal defects measuring 2 mm in length were created in the central 1/3 of mice femora using a circular saw and stabilized with an alveolar distractor device and cerclage wires. Three groups were evaluated: Group I, PTH 30 mg/kg injection daily, Group II, PTH 30 mg/kg injection daily þ DBM, and Group III, DBM þ 30mL saline injection. PTH was given for 28 days or until the time of sacrifice. Animals were sacrificed at 7, 14, 28, and 56 days. Radiographs at the time of sacrifice were evaluated using a 5-point scaled scoring system. Radiographs showed a lack of healing across all treatment groups at all time points: Group I, 1.57 þ/À 0.68; Group II, 3.00 þ/À 1.29; and Group III, 2.90 þ/À 1.03. Bone formation in the defect as measured by radiographic healing score was significantly better at 56 days in Groups II (p ¼ 0.01) and III (p < 0.01) compared to Group I. Across all treatment groups and time points the defects were largely absent of osteoprogenitor cells based on gross observation of frozen histology and quantitation of cellular based histomorphometric parameters. Quantitation of frozen histologic slides showed a limited osteoprogenitor response to PTH and DBM. Our results suggest that the anabolic agent teriparatide is unable to induce healing in a critical sized mouse femoral defect when given alone or in combination with the DBM preparation we used as a local bone graft substitute.
Meckel's diverticulum is the most common congenital abnormality of the gastrointestinal tract and it is found to affect nearly 2 percent of the population. Interestingly, the surgical management of an asymptomatic Meckel's diverticulum remains widely controversial in the adult population. Review of the literature finds the overall risk of Meckel's diverticulum becoming symptomatic to be low; however, the risk accompanying its resection also proves to be minimal thus perpetuating the question of its proper management. We report our experience with an elderly patient who required an emergent operative intervention and was incidentally found to have Meckel's diverticulum. Review of final pathology found Meckel's diverticulum to contain a carcinoid tumor. In our review, the presence of a carcinoid tumor within Meckel's diverticulum is a rare finding, but its incidence may further support the resection of incidentally found asymptomatic Meckel's diverticulum in patients of all ages.
Naltrexol and its C₆ α and β desoxy, iodo, mesyl, tosyl, trifyl, dimethylcarbamyl, and diphenylcarbamyl derivatives were studied in their energy-minimized C ring chair-like and boat-like conformations using B3LYP/6-31G** and SM5.4/A to estimate aqueous solvation free energy. The results were compared to experimental opioid receptor binding affinities. The total energy difference between β conformers correlated well with MOR binding affinity, while the aqueous solvation free energy correlated well with the KOR binding affinity.
Routine full-length spine radiographs used with high frequency in the first 6 months after posterior spinal fusion rarely detected a radiographical abnormality that resulted in a meaningful change to a patient's clinical management. Blanket postoperative screening algorithms should be reconsidered to minimize patient radiation exposure.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.