The effect of an exercise program in patients with thumb base osteoarthritis:A prospective cohort study with propensity score matching

Aim: This study compares the effect of a combination of an exercise program and splintingwith splinting alone on pain and activities in daily life (ADL) in patients osteoarthritis (OA) ofthe thumb base joint (CMC-1). Furthermore, this study investigates predictors for outcomeson pain and ADL in order to optimize healthcare for individual patients with CMC-1 OA.Methods: A prospective cohort study was conducted in eleven outpatient clinics for handsurgery and hand therapy in the Netherlands. A combination of an exercise program andsplinting was compared with splinting alone using propensity score matching (PSM). Primaryoutcomes included pain and ADL at three months, measured with a Visual Analogue Scale(VAS) and the Michigan Hand outcomes Questionnaire (MHQ). Linear mixed model analysiswas used to study between-group differences and multiple regression analysis on baselinecharacteristics for the total exercise program group was used in order to identify predictorsfor outcome.Results: In total, 107 participants were included, of which 44 were matched using PSM. Alarger decrease in VAS pain during physical load was found in the exercise program group(35 points) compared to the splint group (19.5 points, p=0.012). Outcomes on the MHQ scoreshowed no clinically relevant differences. Treatment of the dominant side, higher flexion ofthe first metacarpophalangeal joint, higher age and type of work with heavy physical laborpredicted outcomes on pain or ADL for the total exercise program group (N=85).Conclusion: Superior results were found for the exercise program group when compared tothe splint group, indicating positive effects of an exercise program. Furthermore, severalpredictors for outcomes on splinting combined with an exercise program were identified.Future research should study exercise programs and predictors of outcome in a larger sampleand a more standardized setting.Clinical Relevance: Applying exercise programs in clinical practice appears to be beneficial forindividual patients with CMC-1 OA

The effect of an exercise program in patients with thumb base osteoarthritis:A prospective cohort study with propensity score matching

Aim: This study compares the effect of a combination of an exercise program and splintingwith splinting alone on pain and activities in daily life (ADL) in patients osteoarthritis (OA) ofthe thumb base joint (CMC-1). Furthermore, this study investigates predictors for outcomeson pain and ADL in order to optimize healthcare for individual patients with CMC-1 OA.Methods: A prospective cohort study was conducted in eleven outpatient clinics for handsurgery and hand therapy in the Netherlands. A combination of an exercise program andsplinting was compared with splinting alone using propensity score matching (PSM). Primaryoutcomes included pain and ADL at three months, measured with a Visual Analogue Scale(VAS) and the Michigan Hand outcomes Questionnaire (MHQ). Linear mixed model analysiswas used to study between-group differences and multiple regression analysis on baselinecharacteristics for the total exercise program group was used in order to identify predictorsfor outcome.Results: In total, 107 participants were included, of which 44 were matched using PSM. Alarger decrease in VAS pain during physical load was found in the exercise program group(35 points) compared to the splint group (19.5 points, p=0.012). Outcomes on the MHQ scoreshowed no clinically relevant differences. Treatment of the dominant side, higher flexion ofthe first metacarpophalangeal joint, higher age and type of work with heavy physical laborpredicted outcomes on pain or ADL for the total exercise program group (N=85).Conclusion: Superior results were found for the exercise program group when compared tothe splint group, indicating positive effects of an exercise program. Furthermore, severalpredictors for outcomes on splinting combined with an exercise program were identified.Future research should study exercise programs and predictors of outcome in a larger sampleand a more standardized setting.Clinical Relevance: Applying exercise programs in clinical practice appears to be beneficial forindividual patients with CMC-1 OA

Vortices in polariton OPO superfluids

This chapter reviews the occurrence of quantised vortices in polariton fluids, primarily when polaritons are driven in the optical parametric oscillator (OPO) regime. We first review the OPO physics, together with both its analytical and numerical modelling, the latter being necessary for the description of finite size systems. Pattern formation is typical in systems driven away from equilibrium. Similarly, we find that uniform OPO solutions can be unstable to the spontaneous formation of quantised vortices. However, metastable vortices can only be injected externally into an otherwise stable symmetric state, and their persistence is due to the OPO superfluid properties. We discuss how the currents charactering an OPO play a crucial role in the occurrence and dynamics of both metastable and spontaneous vortices.Comment: 40 pages, 16 figure

A Unifying Theory of Biological Function

A new theory that naturalizes biological function is explained and compared with earlier etiological and causal role theories. Etiological theories explain functions from how they are caused over their evolutionary history. Causal role theories analyze how functional mechanisms serve the current capacities of their containing system. The new proposal unifies the key notions of both kinds of theories, but goes beyond them by explaining how functions in an organism can exist as factors with autonomous causal efficacy. The goal-directedness and normativity of functions exist in this strict sense as well. The theory depends on an internal physiological or neural process that mimics an organism’s fitness, and modulates the organism’s variability accordingly. The structure of the internal process can be subdivided into subprocesses that monitor specific functions in an organism. The theory matches well with each intuition on a previously published list of intuited ideas about biological functions, including intuitions that have posed difficulties for other theories

Disorder Effects on Exciton-Polariton Condensates

The impact of a random disorder potential on the dynamical properties of Bose Einstein condensates is a very wide research field. In microcavities, these studies are even more crucial than in the condensates of cold atoms, since random disorder is naturally present in the semiconductor structures. In this chapter, we consider a stable condensate, defined by a chemical potential, propagating in a random disorder potential, like a liquid flowing through a capillary. We analyze the interplay between the kinetic energy, the localization energy, and the interaction between particles in 1D and 2D polariton condensates. The finite life time of polaritons is taken into account as well. In the first part, we remind the results of [G. Malpuech et al. Phys. Rev. Lett. 98, 206402 (2007).] where we considered the case of a static condensate. In that case, the condensate forms either a glassy insulating phase at low polariton density (strong localization), or a superfluid phase above the percolation threshold. We also show the calculation of the first order spatial coherence of the condensate versus the condensate density. In the second part, we consider the case of a propagating non-interacting condensate which is always localized because of Anderson localization. The localization length is calculated in the Born approximation. The impact of the finite polariton life time is taken into account as well. In the last section we consider the case of a propagating interacting condensate where the three regimes of strong localization, Anderson localization, and superfluid behavior are accessible. The localization length is calculated versus the system parameters. The localization length is strongly modified with respect to the non-interacting case. It is infinite in the superfluid regime whereas it is strongly reduced if the fluid flows with a supersonic velocity.Comment: chapter for a book "Exciton Polaritons in Microcavities: New Frontiers" by Springer (2012), the original publication is available at http://www.springerlink.co

Physical Activity After Surgery for Severe Obesity: The Role of Exercise Cognitions

# The Author(s) 2010. This article is published with open access at Springerlink.com Background Physical activity after bariatric surgery is associated with sustained weight loss and improved quality of life. Some bariatric patients engage insufficiently in physical activity. This may be due to exercise cognitions, i.e., specific beliefs about benefits of and barriers to physical exercise. The aim of this study was to examine whether and to what extent both physical activity and exercise cognitions changed at 1 and 2 years post-surgery and whether exercise cognitions predict physical activity. Methods Forty-two bariatric patients (38 women, 4 men; mean age 38±8 years, mean body mass index prior to surgery 47±6 kg/m 2) filled out self-report instruments to examine physical activity and exercise cognitions pre- and post-surgery

Tau Interaction with Tubulin and Microtubules: From Purified Proteins to Cells

International audienceMicrotubules (MTs) play an important role in many cellular processes and are dynamic structures regulated by an important network of microtubules-associated proteins, MAPs, such as Tau. Tau has been discovered as an essential factor for MTs formation in vitro, and its region implicated in binding to MTs has been identified. By contrast, the affinity, the stoichiometry, and the topology of Tau-MTs interaction remain controversial. Indeed, depending on the experiment conditions a wide range of values have been obtained. In this chapter, we focus on three biophysical methods, turbidimetry, cosedimentation assay, and Förster Resonance Energy Transfer to study Tau-tubulin interaction both in vitro and in cell. We highlight precautions that must be taken in order to avoid pitfalls and we detail the nature of the conclusions that can be drawn from these methods about Tau-tubulin interaction