Pain prediction by serum biomarkers of bone turnover in people with knee osteoarthritis: an observational study of TRAcP5b and cathepsin K in OA

Objectives: To investigate serum biomarkers, tartrate resistant acid phosphatase 5b (TRAcP5b) and cathepsin K, indicative of osteoclastic bone resorption, and their relationship to pain and pain change in knee osteoarthritis (OA). Methods: Sera and clinical data were collected from 129 people (97 with 3-year follow-up) with knee OA from the Prediction of Osteoarthritis Progression (POP) cohort. Knee OA-related outcomes in POP included: WOMAC pain, NHANES I (pain, aching and stiffness), subchondral sclerosis, and radiographically determined tibiofemoral and patellofemoral OA. Two putative osteoclast biomarkers were measured in sera: TRAcP5b and cathepsin K. Medial tibia plateaux were donated at knee arthroplasty for symptomatic OA (n=84) or from 16 post mortem controls from the Arthritis Research UK (ARUK) Pain Centre joint tissue repository. Osteoclasts were stained for TRAcP within the subchondral bone of the medial tibia plateaux. Results: Serum TRAcP5b activity, but not cathepsin K-immunoreactivity, was associated with density of TRAcP-positive osteoclasts in the subchondral bone of medial tibia plateaux. TRAcP-positive osteoclasts were more abundant in people with symptomatic OA compared to controls. Serum TRAcP5b activity was associated with baseline pain and pain change. Conclusions: Our observations support a role for subchondral osteoclast activity in the generation of OA pain. Serum TRAcP5b might be a clinically relevant biomarker of disease activity in OA

Effect of Irradiation and/or Leucocyte Filtration on RBC Storage Lesions

Red blood cell (RBC) storage lesions have been shown to be associated with some adverse reactions; numerous studies have focused on the lesions caused by storage, and few data on the RBC storage lesions caused by prestorage treatments of leucocyte filtration and irradiation. In this study, we examined the changes related with the RBC storage lesions, including 2,3-diphosphatidylglyceric acid (2,3-DPG), pH, free hemoglobin (Hb), supernatant free K+ and Na+ concentration, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH). Along with the increasing storage time, decreases in 2, 3-DPG levels, pH and Na+ concentration, increases in K+ and free Hb concentrations, and significant morphological changes in RBC in all groups were found. The changes in the groups of irradiation, leucocyte filtration and the combined irradiation and leucocyte filtration were more significant than those in the untreated group. Meanwhile, the MCV levels of the three treated groups were significantly lower than those in the untreated group, while the MCH variations were significantly higher. Our results suggest that irradiation and leucocyte filtration before storage may aggravate blood storage lesions

Observation of free electron cyclotron resonance in NaAlSi3O8 feldspar: Direct determination of the effective electron mass

We report the first observation of cyclotron resonances in alkali feldspars, using highly sensitive optical detection methods. In Na-feldspar (NaAlSi3O8). a near isotropic effective electron mass value of m(c)(*) = 0.79m, has been determined. The significance of this measurement in terms of the optical transition energies of shallow donor centres is considered.</p

First International Intercomparison of Luminescence Techniques Using Samples from the Teche River Valley.

Bricks collected from a contaminated village (Muslyumovo) of the lower Techa river valley, Southern Urals, Russia, were measured using thermoluminescence and optically stimulated luminescence by four European laboratories and a U.S. laboratory to establish and compare the applied dose reconstruction methodologies. The bricks, collected from 60-100-year-old buildings, had accumulated a relatively high dose due to natural sources of radiation in the brick and from the surrounding environment. This work represents the results of a first international intercomparison of luminescence measurements for bricks from the Southern Urals. The luminescence measurements of absorbed dose in bricks collected from the most shielded locations of the same buildings were used to determine the background dose due to natural sources of radiation and to validate the age of the bricks. The absorbed dose in different bricks measured by four laboratories using thermoluminescence and optically stimulated luminescence at a depth of 10 +/- 2.5 mm from the exposed brick surface agreed within +/-21%. After subtraction of the natural background dose, the absorbed dose in brick due to contaminated river sediments and banks was calculated and found to range between 150 and 200 mGy. The cumulative doses in brick due to man-made sources of radiation at 100 and 130 mm depths in the bricks were also measured and found to be consistent with depth dose profiles calculated by Monte Carlo simulations of photon transport for possible source distributions