Регіональні й глобальні наслідки незалежності Косово

У статті розглянуто регіональні й міжнародні аспекти проголошення незалежності Косово. Проаналізовано конфліктні аспекти косовської проблеми у регіональному й глобальному контекстах.В статье рассматриваются региональные и международные аспекты провозглашения независимости Косово. Проанализировано конфликтные аспекты косовской проблемы в региональном и глобальном контекстах.The article presents the regional and international aspects of Kosovo Independents. Special attention is to the conflict of Kosovo in the regional and global context

Estimation of articular cartilage properties using multivariate analysis of optical coherence tomography signal

SummaryObjectiveThe aim was to investigate the applicability of multivariate analysis of optical coherence tomography (OCT) information for determining structural integrity, composition and mechanical properties of articular cartilage.DesignEquine osteochondral samples (N = 65) were imaged with OCT, and their total attenuation and backscattering coefficients (μt and μb) were measured. Subsequently, the Mankin score, optical density (OD) describing the fixed charge density, light absorbance in amide I region (Aamide), collagen orientation, permeability, fibril network modulus (Ef) and non-fibrillar matrix modulus (Em) of the samples were determined. Partial least squares (PLS) regression model was calculated to predict tissue properties from the OCT signals of the samples.ResultsSignificant correlations between the measured and predicted mean collagen orientation (R2 = 0.75, P < 0.0001), permeability (R2 = 0.74, P < 0.0001), mean OD (R2 = 0.73, P < 0.0001), Mankin scores (R2 = 0.70, P < 0.0001), Em (R2 = 0.50, P < 0.0001), Ef (R2 = 0.42, P < 0.0001), and Aamide (R2 = 0.43, P < 0.0001) were obtained. Significant correlation was also found between μb and Ef (ρ = 0.280, P = 0.03), but not between μt and any of the determined properties of articular cartilage (P > 0.05).ConclusionMultivariate analysis of OCT signal provided good estimates for tissue structure, composition and mechanical properties. This technique may significantly enhance OCT evaluation of articular cartilage integrity, and could be applied, for example, in delineation of degenerated areas around cartilage injuries during arthroscopic repair surgery

Magnetic Resonance Imaging of Cartilage Repair: A Review

Articular cartilage lesions are a common pathology of the knee joint, and many patients may benefit from cartilage repair surgeries that offer the chance to avoid the development of osteoarthritis or delay its progression. Cartilage repair surgery, no matter the technique, requires a noninvasive, standardized, and high-quality longitudinal method to assess the structure of the repair tissue. This goal is best fulfilled by magnetic resonance imaging (MRI). The present article provides an overview of the current state of the art of MRI of cartilage repair. In the first 2 sections, preclinical and clinical MRI of cartilage repair tissue are described with a focus on morphological depiction of cartilage and the use of functional (biochemical) MR methodologies for the visualization of the ultrastructure of cartilage repair. In the third section, a short overview is provided on the regulatory issues of the United States Food and Drug Administration (FDA) and the European Medicines Agency (EMEA) regarding MR follow-up studies of patients after cartilage repair surgeries

Cross-Calibration of GE Healthcare Lunar Prodigy and iDXA Dual-Energy X-Ray Densitometers for Bone Mineral Measurements

In long-term prospective studies, dual-energy X-ray absorptiometry (DXA) devices need to be inevitably changed. It is essential to assess whether systematic differences will exist between measurements with the new and old device. A group of female volunteers (21–72 years) underwent anteroposterior lumbar spine L2–L4 (n=72), proximal femur (n=72), and total body (n=62) measurements with the Prodigy and the iDXA scanners at the same visit. The bone mineral density (BMD) measurements with these two scanners showed a high linear association at all tested sites (r=0.962–0.995; p<0.0001). The average iDXA BMD values were 1.5%, 0.5%, and 0.9% higher than those of Prodigy for lumbar spine (L2–L4) (p<0.0001), femoral neck (p=0.048), and total hip (p<0.0001), respectively. Total body BMD values measured with the iDXA were −1.3% lower (p<0.0001) than those measured with the Prodigy. For total body, lumbar spine, and femoral neck, the BMD differences as measured with these two devices were independent of subject height and weight. Linear correction equations were developed to ensure comparability of BMD measurements obtained with both DXA scanners. Importantly, use of equations from previous studies would have increased the discrepancy between these particular DXA scanners, especially at hip and at spine

Impact testing to determine the mechanical properties of articular cartilage in isolation and on bone

The original publication is available at www.springerlink.comNon peer reviewedPostprin

Application of optical coherence tomography enhances reproducibility of arthroscopic evaluation of equine joints

Peer reviewe

Fourier Transform Infrared Spectroscopic Imaging and Multivariate Regression for Prediction of Proteoglycan Content of Articular Cartilage

Fourier Transform Infrared (FT-IR) spectroscopic imaging has been earlier applied for the spatial estimation of the collagen and the proteoglycan (PG) contents of articular cartilage (AC). However, earlier studies have been limited to the use of univariate analysis techniques. Current analysis methods lack the needed specificity for collagen and PGs. The aim of the present study was to evaluate the suitability of partial least squares regression (PLSR) and principal component regression (PCR) methods for the analysis of the PG content of AC. Multivariate regression models were compared with earlier used univariate methods and tested with a sample material consisting of healthy and enzymatically degraded steer AC. Chondroitinase ABC enzyme was used to increase the variation in PG content levels as compared to intact AC. Digital densitometric measurements of Safranin O –stained sections provided the reference for PG content. The results showed that multivariate regression models predict PG content of AC significantly better than earlier used absorbance spectrum (i.e. the area of carbohydrate region with or without amide I normalization) or second derivative spectrum univariate parameters. Increased molecular specificity favours the use of multivariate regression models, but they require more knowledge of chemometric analysis and extended laboratory resources for gathering reference data for establishing the models. When true molecular specificity is required, the multivariate models should be used

Composition of the pericellular matrix modulates the deformation behaviour of chondrocytes in articular cartilage under static loading

The aim was to assess the role of the composition changes in the pericellular matrix (PCM) for the chondrocyte deformation. For that, a three-dimensional finite element model with depth-dependent collagen density, fluid fraction, fixed charge density and collagen architecture, including parallel planes representing the split-lines, was created to model the extracellular matrix (ECM). The PCM was constructed similarly as the ECM, but the collagen fibrils were oriented parallel to the chondrocyte surfaces. The chondrocytes were modelled as poroelastic with swelling properties. Deformation behaviour of the cells was studied under 15% static compression. Due to the depth-dependent structure and composition of cartilage, axial cell strains were highly depth-dependent. An increase in the collagen content and fluid fraction in the PCMs increased the lateral cell strains, while an increase in the fixed charge density induced an inverse behaviour. Axial cell strains were only slightly affected by the changes in PCM composition. We conclude that the PCM composition plays a significant role in the deformation behaviour of chondrocytes, possibly modulating cartilage development, adaptation and degeneration. The development of cartilage repair materials could benefit from this information