Introduction Disorders that affect glucose metabolism, namely diabetes mellitus (DM), may favor the development and/or progression of osteoarthritis (OA). Thus far, little is known regarding the ability of chondrocytes to adjust to variations in the extracellular glucose concentration, resulting from hypoglycemia and hyperglycemia episodes, and so, to avoid deleterious effects resulting from deprivation or intracellular accumulation of glucose. The aim of this study was to compare the ability of normal and OA chondrocytes to regulate their glucose transport capacity in conditions of insufficient or excessive extracellular glucose and to identify the mechanisms involved and eventual deleterious consequences, namely the production of reactive oxygen species (ROS).

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Fractures are ubiquitous in the archaeological record but the majority of these are the consequence of a traumatic incident and do not reflect any loss of strength inherent to the bone. So-called fragility fractures, particularly hip fractures, are considered uncommon occurrences in skeletal populations from the past. Nevertheless, evidence of this type of fracture in the archaeological record is increasing. A methodical search for possible hip fractures in the excavation reports, theses and monographs housed in the Department of Anthropology of the University of Coimbra presented an occasion to describe six hip fractures, previously unpublished, from different Portuguese archaeological sites and to challenge the widespread assumption that hip fractures were nearly non-existent in the past.

Chondrocyte survival is a major goal for the effective storage and clinical performance of human osteochondral allografts. The majority of animal and human cryopreservation studies conducted so far have been performed in small osteochondral cylinders. Using human tibial plateaus as a model for large osteochondral pieces, this work sought to evaluate the cryoprotective efficiency of glycerol and dimethylsulfoxide (DMSO), and to identify cryopreservation conditions suitable for use in tissue banks. Human tibial plateaus harvested from 7 cadaveric tissue donors were incubated in the presence or absence of cryoprotective agents (CPA): 10% or 15% glycerol and 10% DMSO in a Ham F-12 nutrient mixture. Chondrocyte viability was assessed immediately after thawing, using the MTT reduction assay and a fluorescence microscopic method. The tibial plateaus frozen in the absence of CPA showed a significant decrease in chondrocyte viability. The use of CPA significantly increased chondrocyte viability compared with cartilage frozen without CPA (nearly 50% versus 80% living chondrocytes with 10% glycerol versus 10% DMSO, respectively) relative to that in fresh cartilage. In this regard, 10% DMSO was slightly more effective than either 10% or 15% glycerol, eliciting the recovery of approximately 15% relative to the living chondrocyte content in fresh cartilage. In all conditions, fluorescence microscopic studies showed that surviving chondrocytes were restricted to the superficial cartilage layer. Human tibial plateaus seemed to be a good experimental model to establish cryopreservation methods applicable to large human osteochondral pieces in tissue banks.