845 research outputs found
Association between bone marrow lesions & synovitis and symptoms in symptomatic knee osteoarthritis
No full textObjective: Bone marrow lesions (BMLs) on MRI are typically subchondral in location, however, a proportion occur at knee ligament attachments and also include a cyst-like component. Our aim was to determine whether the volume of BML subtypes and synovial tissue volume (STV) was associated with symptoms in symptomatic knee OA. Method: Images were acquired in a sub-sample who had taken part in a randomised trial of vitamin D therapy in knee OA (UK-VIDEO). Contrast-enhanced (CE) MRI was performed annually. In those who had ≥1 follow-up and a baseline scan (N = 50), STV and BML volume was assessed. BMLs were categorised by location and by the presence/absence of a cyst-like component. WOMAC was assessed annually. We used fixed-effects panel-regression modelling to examine the association between volume and symptoms. Results: There was no association between knee pain and total subchondral BML volume (b = 0.3 WOMAC units, 95% CI -0.3 to 1.0) or total ligament-based BML volume (b = 1.9, 95% CI -1.6 to 5.3). The volume of subchondral BMLs with a cyst-like component was not associated with pain (b = 0.8, 95% CI -0.5 to 2.1) however, the volume of the cyst-like component itself was associated with pain (b = 51.8, 95% CI 14.2 to 89.3). STV was associated with pain (b = 2.2, 95% CI 0.6 to 3.7). Conclusion: The volume of the cyst-like component from subchondral BMLs with a cyst-like component was associated with knee pain. BML location, however, did not influence symptoms. STV was also associated with knee symptoms.</p
Nouvelle méthode syntagmatique de vectorisation appliquée au self-organizing map des textes vietnamiens
No full text@inproceedings{CN-NGUYEN-2004, author = {Nguyen D.T.}, title = {Nouvelle méthode syntagmatique de vectorisation appliquée au self-organizing map des textes vietnamiens}, booktitle = {RECIRAL'04}, year = {2004}, address = {Fès, Maroc}, month = {avril} }National audienc
Nonlinear system analysis of local reflex control of locust hind limbs
No full textNonlinear Volterra type system identification models coupled with a Gaussian White Noise (GWN) stimulation signal provide an experimentally convenient and quick way to investigate the often complex and nonlinear interactions between the mechanical and neural elements of invertebrate reflex limb control systems. Previous steady state analysis has allowed the neurons in such systems to be categorised by their sensitivity to position, velocity or acceleration (system dynamics) and has improved understanding of network function. These neurons, however, are known to adapt their output amplitude or spike firing rate during repetitive stimulation and this transient response may be more important than the steady state response for reflex limb control. Furthermore, whilst the use of GWN for system identification can be theoretically and experimentally justified, the properties of this signal are very different from those received by the sensory, inter and motor neurons in the neural networks which monitor the position of the locusts leg under natural operating conditions. The current study provides improvements to the previously used experimental methods, equipment and nonlinear system identification methods. Validation of the models using biologically more realistic stimulation signals has been carried out to determine where they perform well and to identify their limitations. The use of the parsimonious cascade model structure, applied in a quasi stationary fashion coupled with Monte Carlo (MC) simulations, has been shown to provide a useful tool for the characterisation of the dynamics and nonlinear responses of the neuromuscular elements in a locust’s reflex limb control system during both transient and steady state response sections. This method been applied to test the null hypothesis that the dynamics and nonlinear responses of the locust’s Fast Extensor Tibia (FETi) motor neuron system are the same during transient and steady state sections. It can be concluded that key FETi system dynamics remain relatively unchanged during repetitive stimulation while output amplitude adaptation is occurring. Whilst some evidence of a significant change was found in parts of the system’s nonlinear response, the effect was small and probably of little physiological relevance. Analysis using biologically more realistic stimulation reinforces this conclusion
High systemic bone mineral density increases the risk of incident knee OA and joint space narrowing, but not radiographic progression of existing knee OA: the MOST study
No full textObjectives: previous studies suggest that high systemic bone mineral density (BMD) is associated with incident knee osteoarthritis (OA) defined by osteophytes but not with joint space narrowing (JSN), and are inconsistent regarding BMD and progression of existing OA. The association of BMD with incident and progressive tibiofemoral OA was tested in a large prospective study of men and women aged 50–79 years with or at risk for knee OA.Methods: baseline and 30-month weight-bearing posteroanterior and lateral knee radiographs were scored for Kellgren-Lawrence (K-L) grade, JSN and osteophytes. Incident OA was defined as the development of K-L grade ?2 at follow-up. All knees were classified for increases in grade of JSN and osteophytes from baseline. The association of gender-specific quartiles of baseline BMD with risk of incident and progressive OA was analysed using logistic regression, adjusting for covariates.Results: the mean (SD) age of 1754 subjects was 63.2 (7.8) years and body mass index was 29.9 (5.4) kg/m2. In knees without baseline OA, higher femoral neck and whole body BMD were associated with an increased risk of incident OA and increases in grade of JSN and osteophytes (p<0.01 for trends); adjusted odds were 2.3–2.9-fold greater in the highest compared with the lowest BMD quartiles. In knees with existing OA, progression was not significantly related to BMD.Conclusions: in knees without OA, higher systemic BMD was associated with a greater risk of the onset of JSN and K-L grade ?2. The role of systemic BMD in early knee OA pathogenesis warrants further investigatio
Mapping the Landscape: A Bibliometric Analysis of CALIBER 2022 Convention Publications
No full textThe present study examines the authorship patterns, collaboration levels, and various other parameters such as gender, author designation, institutional affiliation, and geographical distribution of the conference papers presented at CALIBER 2022 by employing an array of bibliographic analysis techniques. The analysis is based on a dataset consisting of 45 papers authored by 100 individuals and found that authors hailing from Uttar Pradesh emerged as the foremost contributors. The study also found that universities emerged as the most prolific contributors, responsible for the publication of 71.00 per cent of the articles within the designated time frame
Osteoarthritis as a disease of mechanics
No full textMechanics means relating to or caused by movement or physical forces. In this paper, I shall contend that osteoarthritis (OA) is almost always caused by increased physical forces causing damage to a joint. While examples of joint injury causing OA are numerous, I shall contend that most or almost all OA is caused in part by mechanically induced injury to joint tissues. Further, once joint pathology has developed, as is the case for almost all clinical OA, pathomechanics overwhelms all other factors in causing disease progression. Treatments which correct the pathomechanics have long lasting favorable effects on pain and joint function compared with treatments that suppress inflammation which have only temporary effects. I shall lastly contend that the mechanically induced joint injury leads to variable inflammatory responses but that the role of this inflammation in worsening structural damage in an already osteoarthritic joint has not yet been proven. © 2012 Osteoarthritis Research Society International
The association of meniscal damage with joint effusion in persons without radiographic osteoarthritis: the Framington and MOST osteoarthritis studies
No full textObjective: to assess the cross-sectional association between meniscal status and joint effusion on magnetic resonance imaging (MRI) in knees without radiographic osteoarthritis (OA).Design: knees without OA (Kellgren/Lawrence grade 0) from the Framingham and MOST studies were examined by MRI. Meniscal status was assessed with a score of 0–4 in the anterior horn/body/posterior horn of the medial/lateral meniscus and effusion was assessed using a score of 0–3. The odds ratios (ORs) of joint effusion in those with meniscal damage were estimated using a logistic regression model. A subanalysis was performed for knees without MRI-detected cartilage damage.Results: of 1368 knees, 296 (21.6%) showed meniscal pathology in at least one subregion. Effusion was present in 133 (44.9%) of knees with meniscal damage vs 328 (30.6%) in those without meniscal damage. The adjusted OR of effusion in a knee with meniscal damage was 1.8, 95% confidence intervals (CI) [1.4, 2.4]. The OR of effusion for the group with meniscal pathology in two compartments was 5.4, 95% CI [2.1, 14.3]. For knees without any cartilage lesions but with meniscal damage in any compartment the OR was 2.3, 95% CI [1.1, 4.5].Conclusions: knees without OA but with meniscal pathology exhibit joint effusion to a significantly higher degree than knees without meniscal damage. The association persists for knees without cartilage damage. The prevalence of effusion is further increased when present in two compartments. Concomitant occurrence of synovial activation and meniscal damage contributes to understanding the pathophysiology of early degenerative joint diseas
Eastern Iran in the Achaemenid Period
No full textThe author deals with the archaeological evidence of the Achaemenid period in eastern Iran. This evidence is limited, rare and contradictory with regard to the historical importance of the eastern provinces of the Empire. The territorial extent of the Achaemenid Empire is ambiguous too and in this regard the cultural background of the different provinces, as well as relationships between center and periphery, were crucial factors affecting the visibility of the Achaemenid empire in its eastern-most regions. Similarly, the geographic definition of ‘eastern Iran’ requires clarification as well because, as a geomorphological unit. Thus at least four different aspects of interpretation should be considered when considering the evidence of the Achaemenid empire in the east:
1. the dynastic - identifiable by inscriptions, coins and seals
2. the ethnic - possibly detectable on both physical anthropological and cultural grounds
3. the political/imperial - recognizable both in macroscopic architectural and art historical remains and in the material traces of settlement patterns and economic investments, e.g. to secure the water supply
4. the chronological - interpretable in the differing horizons connected to the period of Achaemenid political-dynastic dominion in the area
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