Proteoglycan synthesis rate as a novel method to measure blood-induced cartilage degeneration in non-haemophilic and haemophilic rats.

INTRODUCTION: Haemophilic animal models are used to study blood-induced cartilage damage, but quantitative and sensitive outcome measures are needed. AIM: To develop a novel quantitative method for detecting early cartilage degeneration in a haemophilic rat model of blood-induced joint damage. METHODS: The 35 Sulphate incorporation (35 SO4 2- assay) was applied to tibial and patellar cartilage of wild-type rats to quantify baseline proteoglycan synthesis and to evaluate the effect of 4-day blood exposure in vitro. Next, haemarthrosis was induced in 39 FVIII-deficient rats and characterized by changes in knee joint diameter and development of bone pathology (using micro-CT). Four- and 16-day posthaemarthrosis proteoglycan synthesis rate (PSR) was assessed using the 35 SO4 2- assay, with the contralateral knee as control. RESULTS: In vitro, a decrease in PSR in tibial and patellar cartilage was demonstrated following blood exposure. In vivo, joint diameter and development of bone pathology confirmed successful induction of haemarthrosis. In the blood-exposed knee, tibial and patellar PSR was inhibited 4 and 16 days after induced haemarthrosis. Interestingly, at day 16 the proteoglycan synthesis in the contralateral knee was also inhibited to an extent correlating with that of the blood-exposed knee. CONCLUSION: For the first time, early changes in cartilage matrix synthesis upon blood exposure were quantified with the 35 SO4 2- assay in a haemophilic rat model, establishing this assay as a novel method to study blood-induced cartilage damage.

Quality of life assessment in dogs and cats receiving chemotherapy - a review of current methods.

This study aimed to review currently reported methods of assessing the effects of chemotherapy on the quality of life (QoL) of canine and feline patients and to explore novel ways to assess QoL in such patients in the light of the experience to date in human pediatric oncology. A qualitative comparative analysis of published papers on the effects of chemotherapy on QoL in dogs and cats were conducted. This was supplemented with a comparison of the parameters and domains used in veterinary QoL-assessments with those used in the Pediatric Quality of Life Inventory (PedsQL™ ) questionnaire designed to assess QoL in toddlers. Each of the identified publications including QoL-assessment in dogs and cats receiving chemotherapy applied a different method of QoL-assessment. In addition, the veterinary QoL-assessments were mainly focused on physical clinical parameters, whereas the emotional (6/11), social (4/11) and role (4/11) domains were less represented. QoL-assessment of cats and dogs receiving chemotherapy is in its infancy. The most commonly reported method to assess QoL was questionnaire based and mostly included physical and clinical parameters. Standardizing and including a complete range of potentially relevant parameters in future QoL assessments may benefit owner decision making.