RAGE activation induces invasiveness of RA fibroblast-like synoviocytes in vitro.

Ligands for the receptor for advanced glycation endproducts (RAGE) are increased in RA synovial fluid (SF), serum and synovium. Since RAGE is present on fibroblast-like synoviocytes (FLS), the present study investigates whether the RAGE ligands HMGB-1 and AGEs are able to stimulate the characteristic, pathological invasive behaviour of these cells. FLS were obtained during joint replacement surgery. FLS were seeded in serum free medium with HMGB-1 or glycated albumin (BSA-AGE) on transwell filters coated with Matrigel. The lower compartment contained medium with serum as a chemoattractant. After three days, the percentage of invading cells was determined and compared to the control invasion. Stimulation with HMGB-1 increased invasiveness to 125% compared to the control (p = 0.001). Addition of anti-RAGE antibody reduced this back to baseline (98%, p = 0.002). Stimulation with BSA-AGE, another RAGE ligand, increased invasiveness to 150% compared to the control (p = 0.003). Addition of anti RAGE was again able to reduce the increased invasiveness back to baseline (95%, p = 0.008). HMGB-1 and BSA-AGE stimulated the invasiveness of RA-FLS by activation of RAGE. As such, RAGE may be an interesting target for therapy directed at the inhibition of synoviocyte activation.

Recto-colonic reflex is impaired in patients with irritable bowel syndrome.

Motor and sensory dysfunction of the gut are present in a subset of patients with irritable bowel syndrome (IBS). Recent studies have demonstrated the presence of a recto-colonic inhibitory reflex in healthy humans. It is not known whether this reflex exists in IBS. We studied rectal compliance, perception and the recto-colonic reflex by measuring volume responses of the descending colon to rectal distentions by barostat in 26 IBS patients and 13 healthy controls under both fasting and postprandial conditions. In the fasting state, rectal distention inhibited colonic tone and phasic motility to a similar extent in health and IBS. After a meal, rectal distention inhibited colonic tone and phasic motility to a lesser degree (P < 0.05) in IBS than health. Under postprandial but not fasting conditions, rectal distentions of increasing intensity were associated with higher pain scores in IBS than in health. Rectal distention inhibits tonic and phasic motility of the descending colon in healthy controls and in IBS patients. Postprandially this recto-colonic inhibitory reflex is impaired and attenuated in IBS patients compared with controls. These findings point to an altered reflex function in IBS and have implications for pathophysiology and therapy.

Fibroblast-like synoviocyte-chondrocyte interaction in cartilage degradation.

OBJECTIVE: In vitro models for joint diseases often focus on a single cell type, such as chondrocytes in osteoarthritis (OA) or fibroblast-like synoviocytes (synoviocytes) in rheumatoid arthritis (RA). However, these joint diseases affect the whole joint and interaction between chondrocytes and synoviocytes may play an important role in disease pathology. The current study was designed to study the use of the alginate recovered chondrocyte method as a model for cartilage degradation and to study interaction between chondrocytes and synoviocytes. METHODS: Bovine chondrocytes were cultured in alginate beads for 1 week, subsequently chondrons were retrieved and seeded into transwells. Every two days cartilage-slices were analysed for proteoglycan content (colorimetric, Blyscan GAG kit), collagen content (HPLC) and collagen HP and LP crosslinking (HPLC). For degradation experiments, monocultures of cartilage-slices labelled with (35)S and cocultures with synoviocytes were stimulated with IL-1beta or TNF-alpha. After 7 days, (35)S release was measured taken as a measure of cartilage degradation. RESULTS: After biochemical analysis, three week old cartilage-like slices were chosen to perform cartilage-degradation experiments. Synoviocytes were able to induce cartilage degradation only in the presence of living chondrocytes. In addition, the cytokines interleukin 1 (IL-1beta) and tumor necrosis factor (TNF-alpha) were only able to induce cartilage degradation by chondrocytes, not by synoviocytes. CONCLUSION: These data indicate that the alginate recovered chondrocyte method provides a novel model for cartilage degradation in which the interaction between synoviocytes and chondrocytes can be studied.

[Reversible tooth discoloration during oral use of antibiotics]. / Reversibele tandverkleuring tijdens oraal gebruik van antibiotica.

From January 1991 until June 1995. 25 cases were reported to the Netherlands Pharmacovigilance Foundation LAREB of yellow to brown tooth discoloration following the oral use of medication; 21 cases (84%) involved antibiotics, of which 14 were amoxicillin. 17/21 patients were children, with ages ranging from 1 to 10 years. All children used liquid formulations (suspension or solutabs). Discoloration was reversible in all cases, but had a protracted course in some. Presumably a pigment precipitated on (and not in) the teeth, but the nature of the pigment was uncertain.

[Comprehensive care for the elderly in The Netherlands: current status and potential improvements]. / Mantelzorg voor ouderen in Nederland: de stand van zaken en mogelijke verbeteringen.

Family care is important for older people who are in need of some kind of care and who live in their own home. Sometimes support from services for family caretakers is essential for them to continue caring. The existing possibilities to get this support are not sufficiently available in the Netherlands: if someone is in need of support at the emotional, practical or material level, services are scarce. In order to change this situation, some recommendations are made. A change in attitude towards family caregiving is the most important one.