Genomewide molecular and biologic characterization of biomembrane formation adjacent to a methacrylate spacer in the rat femoral segmental defect model.

Objectives: This study focuses upon the morphologic and molecular features of the layer of cells, termed the "biomembrane," which forms around methacrylate spacers in bone segmental defects. The objective of this research was to assess the biomembrane formed in a novel rodent femoral segmental defect model at 4, 8, and 16 weeks with histologic and molecular studies.

Methods: Following Institutional Animal Care and Use Committee approval, a segmental defect was created in the rat femur and stabilized with the AO LockingRatNail and analyzed at 4, 8, and 16 weeks postsurgery using digital radiologic imaging, morphological and immunohistochemical studies, and genomewide gene expression studies employing microarray analysis.

Rationale, design and clinical performance of the mechanical response tissue analyser: a non-invasive technology for measurement of long bone bending stiffness.

Prediction of osteoporotic fractures is currently an imperfect science and new tools are desperately needed to identify at-risk patients at an earlier stage in the disease process. The mechanical response tissue analyser (MRTA) is a novel, non-invasive, radiation-free device that measures the bending stiffness of long bones in vivo, an indicator of a bone's ability to resist deformation under a given load and a strong predictor of long bone structural integrity and strength. Bone bending stiffness measured with the MRTA has been consistently shown to be a stronger predictor of post-mortem and ex vivo bone breaking strength compared to bone mineral measured with dual-energy X-ray absorptiometry.

Fat and muscle indices assessed by pQCT: relationships with physical activity and type 2 diabetes risk.

The aim of this study was to compare and determine the repeatability of foreleg and forearm muscle and fat indices evaluated by the peripheral quantitative computed tomography (pQCT). Effects of habitual physical activity and associated health risk of type 2 diabetes were examined within the interrelations of intermuscular adipose tissue (IMAT) and muscle density. Eighty-two premenopausal women (mean age ± standard deviation: 38.

Osteogenic and chondrogenic potential of biomembrane cells from the PMMA-segmental defect rat model.

A layer of cells (the "biomembrane") has been identified in large segmental defects between bone and surgically placed methacrylate spacers or antibiotic-impregnated cement beads. We hypothesize that this contains a pluripotent stem cell population with potential valuable applications in orthopedic tissue engineering. Objectives using biomembranes harvested from rat segmental defects were to: (1) Culture biomembrane cells in specialized media to direct progenitor cells along bone or cartilage cell differentiation lineages; (2) evaluate harvested biomembranes for mesenchymal stem cell markers, and (3) define relevant gene expression patterns in harvested biomembranes using microarray analysis.

A review of weight loss following Roux-en-Y gastric bypass vs restrictive bariatric surgery: impact on adiponectin and insulin.

Background: Bariatric surgery is a common procedure often used to ameliorate comorbidities associated with obesity, including type 2 diabetes. Substantial weight loss leads to alterations in inflammation and insulin sensitivity as well as numerous metabolic and physiologic pathways. Several inflammatory markers have been evaluated, yet adiponectin, an anti-inflammatory adipokine, has not been fully investigated.