The arthropathy of Sjögren's syndrome.
ABSTRACT The clinical course of 48 patients with primary SS has been reviewed with particular reference to the articular manifestations. The incidence of arthritis and/or arthralgia was 54%. In a third of these patients it was a presenting feature and preceded sicca symptoms. The arthropathy tended to be polyarticular, the most frequent joint involved being the knee. It was symmetrical in 55% of cases. Joint symptoms or signs were intermittent, lasting less than a month in 55% of cases. The acute onset of purpuric vasculitis was associated with an acute arthritis in four out of the nine patients with such a vasculitis. Joint deformity was unusual, ulnar deviation occurring in only six patients. Hand X-rays obtained from primary SS patients revealed evidence of joint erosions in 33% of PIP joints, 27% of MCP joints and 12% of wrist joints.
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ABSTRACT: Water forms the basis of lubrication in the human body, but is unable to provide sufficient lubrication without additives. The importance of biolubrication becomes evident upon aging and disease, particularly under conditions that affect secretion or composition of body fluids. Insufficient biolubrication, may impede proper speech, mastication and swallowing, underlie excessive friction and wear of articulating cartilage surfaces in hips and knees, cause vaginal dryness, and result in dry, irritated eyes. Currently, our understanding of biolubrication is insufficient to design effective therapeutics to restore biolubrication. Aim of this study was to establish the role of structure and glycosylation of adsorbed protein films in biolubrication, taking the oral cavity as a model and making use of its dynamics with daily perturbations due to different glandular secretions, speech, drinking and eating, and tooth brushing. Using different surface analytical techniques (a quartz crystal microbalance with dissipation monitoring, colloidal probe atomic force microscopy, contact angle measurements and X-ray photo-electron spectroscopy), we demonstrated that adsorbed salivary conditioning films in vitro are more lubricious when their hydrophilicity and degree of glycosylation increase, meanwhile decreasing their structural softness. High-molecular-weight, glycosylated proteins adsorbing in loops and trains, are described as necessary scaffolds impeding removal of water during loading of articulating surfaces. Comparing in vitro and in vivo water contact angles measured intra-orally, these findings were extrapolated to the in vivo situation. Accordingly, lubricating properties of teeth, as perceived in 20 volunteers comprising of equal numbers of male and female subjects, could be related with structural softness and glycosylation of adsorbed protein films on tooth surfaces. Summarizing, biolubrication is due to a combination of structure and glycosylation of adsorbed protein films, providing an important clue to design effective therapeutics to restore biolubrication in patients with insufficient biolubrication.PLoS ONE 01/2012; 7(8):e42600. · 4.09 Impact Factor