ObjectivesThe current paper explores the effectiveness of entheseal changes as skeletal activity markers by testing the correlation between such changes and cross-sectional geometric (CSG) properties while controlling for the effect of age and body size. Materials and MethodsThe originality of the paper lies in capturing entheseal changes in a continuous quantitative manner using 3D microscopy. Roughness and bone resorption were recorded on zone 1 and 2 of three humeral entheses (subscapularis, supraspinatus, infraspinatus) in a documented sample of 29 male skeletons. ResultsOur analysis found that merely 5.91% of the partial correlations between entheseal changes and CSG properties were statistically significant. In addition, two unexpected patterns were identified, namely a higher number of significant correlations on the left side entheses compared to the right side ones and a higher number of correlations between minimum roughness and CSG properties compared to mean and maximum roughness. DiscussionThese patterns are the inverse of what we would expect if activity had exerted an important effect on entheseal change expression. Therefore, they support the lack of association between entheseal changes and habitual activity, even though various factors potentially affecting the above results are discussed.

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Background Acute phase response (APR) is characterized by a change in concentration of different proteins, including C-reactive protein and serum amyloid A (SAA) that can be linked to both exposure to metal oxide nanomaterials and risk of cardiovascular diseases. In this study, we intratracheally exposed mice to ZnO, CuO, Al2O3, SnO2 and TiO2 and carbon black (Printex 90) nanomaterials with a wide range in phagolysosomal solubility. We subsequently assessed neutrophil numbers, protein and lactate dehydrogenase activity in bronchoalveolar lavage fluid, Saa3 and Saa1 mRNA levels in lung and liver tissue, respectively, and SAA3 and SAA1/2 in plasma. Endpoints were analyzed 1 and 28 days after exposure, including histopathology of lung and liver tissues. Results All nanomaterials induced pulmonary inflammation after 1 day, and exposure to ZnO, CuO, SnO2, TiO2 and Printex 90 increased Saa3 mRNA levels in lungs and Saa1 mRNA levels in liver. Additionally, CuO, SnO2, TiO2 and Printex 90 increased plasma levels of SAA3 and SAA1/2. Acute phase response was predicted by deposited surface area for insoluble metal oxides, 1 and 28 days post-exposure. Conclusion Soluble and insoluble metal oxides induced dose-dependent APR with different time dependency. Neutrophil influx, Saa3 mRNA levels in lung tissue and plasma SAA3 levels correlated across all studied nanomaterials, suggesting that these endpoints can be used as biomarkers of acute phase response and cardiovascular disease risk following exposure to soluble and insoluble particles.

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Loose sand formations greatly reduce the efficiency of oil pumping from sandy soil reservoirs. Studies of the in-situ deposition of calcium phosphate salts gave promising results, which indicated that consolidation may be achieved through the formation of salt bridges between sand grains. The formation of micron-sized platelike crystallites is desirable for the achievement of maximum sand consolidation with minimal loss of fluid permeability. In the calcium phosphate system, this crystal morphology corresponds to the formation of octacalcium phosphate (Ca8H2(PO4)6·5H2O, OCP). In the present work, precipitation of calcium phosphate phases from supersaturated solutions on silicate sand substrates was investigated. Because OCP is thermodynamically unstable, the conditions at which this phase may be stabilized was studied with kinetics measurements in batch reactors. Experiments were done in supersaturated solutions seeded with silicate sand over the temperature range from 25 to 70 °C and initial solution pH values 6.0, 7.0, and 8.0. The ionic strength adjusted with sodium chloride was 0.1 and 0.5 M; the solution supersaturation was varied using different calcium and phosphate concentrations (2−20 mM). Clean, dry sand with an average grain size diameter < 0.2 mm was used to seed supersaturated calcium phosphate solutions to determine the influence of the sand grains on the kinetics of formation of the precipitating phase and to investigate the extent of stabilization of calcium phosphates less stable than the thermodynamically most stable hydroxyapatite (Ca5 (PO4)3OH, HAP). A detailed parametric study showed that the experimental conditions of the supersaturated solutions determined the nature of the calcium phosphates forming. Dicalcium phosphate dihydrate (CaHPO4·2H2O, DCPD) the least stable thermodynamically crystalline form of calcium phosphate formed predominantly at 25 °C and initial pH values lower than 7.0. In the presence of sand grain substrates, DCPD was stabilized to some extent even at relatively high pH. At 50 °C, the formation of DCPD was found to result in a drop of the solution pH to 6.0. At 70 °C, however, no DCPD was detected over the pH range investigated. OCP and HAP were the predominant phases at 50 and 70 °C both in the presence and in the absence of sand. Sand was found to favor the formation of OCP at higher pH values. The ionic strength of the supersaturated solutions adjusted with sodium chloride did not have any appreciable effect on the nature of the calcium phosphate phases nucleated on the sand grains.