Lubricin in experimental and naturally occurring osteoarthritis: a systematic review

OBJECTIVE

Lubricin is increasingly being evaluated as an outcome measure in studies investigating post-traumatic and naturally occurring osteoarthritis. However, there are discrepancies in results, making it unclear as to whether lubricin is increased, decreased or unchanged in osteoarthritis. The purpose of this study was to review all papers that measured lubricin in joint injury or osteoarthritis in order to draw conclusions about lubricin regulation in joint disease.

DESIGN

A systematic search of the Pubmed, Web of Knowledge, and EBSCOhost databases for papers was performed. Inclusion criteria were in vivo studies that measured lubricin in humans or animals with joint injury, that investigated lubricin supplementation in osteoarthritic joints, or that described the phenotype of a lubricin knock-out model. A methodological assessment was performed.

RESULTS

Sixty-two studies were included, of which thirty-eight measured endogenous lubricin in joint injury or osteoarthritis. Nineteen papers found an increase or no change in lubricin and nineteen reported a decrease. Papers that reported a decrease in lubricin were cited four times more often than those that reported an increase. Fifteen papers described lubricin supplementation, and all reported a beneficial effect. Eleven papers described lubricin knock-out models.

CONCLUSIONS

The human literature reveals similar distributions of papers reporting increased lubricin as compared to decreased lubricin in osteoarthritis. The animal literature is dominated by reports of decreased lubricin in the rat anterior cruciate ligament transection model, whereas studies in large animal models report increased lubricin. Intra-articular lubricin supplementation may be beneficial regardless of whether lubricin increases or decreases in OA.

Perineural versus intravenous dexamethasone as adjuncts to local anaesthetic brachial plexus block for shoulder surgery

This randomised, double-blind, placebo-controlled study compared the effect of perineural with intravenous dexamethasone, both administered concomitantly with interscalene brachial plexus block for shoulder surgery. Patients received 8 mg dexamethasone mixed with ropivacaine in the block injection (n = 42), 8 mg dexamethasone intravenously at the time of the block (n = 37), or intravenous saline (n = 41) at the time of the block. Perineural and intravenous dexamethasone resulted in prolonged mean (SD) duration of block to 16.9 (5.2) h and 18.2 (6.4) h, respectively, compared with 13.8 (3.8) h for saline (p = 0.001). Mean (SD) opioid consumption (morphine equivalents) during the first 24 h after postanaesthesia recovery arrival was 12.2 (9.3) mg in the perineural dexamethasone, 17.1 (15.9) mg in the intravenous dexamethasone and 24.1 (14.3) mg in the saline groups (p = 0.001). Dexamethasone via either route reduced anti-emetic use (p = 0.046). There was no effect on patient satisfaction. These results suggest that both perineural and intravenous dexamethasone are useful adjuncts to ropivacaine interscalene block, with the intravenous route preferred as this avoids the possibility of neural toxicity of dexamethasone.

The effects of single and multiple doses of thiabendazole on growing and arrested stages of the rabbit stomach worm Obeliscoides cuniculi

Preliminary observations, using 5 rabbits carrying long-standing infections, indicated that single doses of thiabendazole were effective against adult O. cuniculi and that repeated doses may have had some effect on arrested larvae. A multiple dosing regime, consisting of 1 dose at 110 mg kg-1 body weight followed by 8 doses at 70 mg kg-1 body weight at 4-h intervals, was successful in removing 99.12% of developing worms and 86.04% of arrested larvae.

Electron-transfer fluorescence quenching by aliphatic amines

Electron-transfer interaction of an excited aromatic molecule with an aliphatic tertiary amine leads to a pattern of intermediate products not to be expected from earlier work with aromatic amines. The reasons for this phenomenon are briefly discussed.

Kinetic medium effects. IV. Transition state activity coefficients in mixed solvents

The kinetics of acid hydrolysis of a number of aliphatic acetals have been studied in dimethyl sulphoxide-water and dioxan-water mixtures. Where possible, experimentally measured medium activity coefficients for the acetals in the solvent systems have been used in order to calculate the transition state activity coefficients as a function of solvent composition. These activity coefficients are compared with those calculated for the transition states of other hydrolytic reactions, and with the known activity coefficients of some stable ions. The results show no features inconsistent with the assumptions of transition state theory.

Kinetic medium effects. II. Hydrolysis of esters in electrolyte solutions

Rate constants have been measured for the acid-catalysed hydrolyses of t-butyl acetate and methyl chloroacetate in various aqueous electrolyte solutions; the activity coefficients of the esters in these electrolyte solutions have also been measured. The results are used to test a recently proposed method of determining transition state hydration numbers for reactions in aqueous media.