Thaís S.L. Machado

Urinary glycosaminoglycans in horse osteoarthritis. Effects of chondroitin sulfate and glucosamine

Our objectives were to characterize the urinary excretion of glycosaminoglycans (GAGs) in horse osteoarthritis, and to investigate the effects of chondroitin sulfate (CS) and glucosamine (GlcN) upon the disease. Urinary GAGs were measured in 47 athletic horses, 20 healthy and 27 with osteoarthritis. The effects of CS and GlcN were investigated in mild osteoarthritis. In comparison to normal, urinary GAGs were increased in osteoarthritis, including mild osteoarthritis affecting only one joint. Treatment with CS+GlcN led to a long lasting increase in the urinary CS and keratan sulfate (KS), and significant improvement in flexion test of tarsocrural and metacarpophalangeal joints was observed. In conclusion, urinary CS and KS seems to reflect the turnover rates of cartilage matrix proteoglycans, and the measurement of these compounds could provide objective means of evaluating and monitoring joint diseases.

Synovial fluid chondroitin sulphate indicates abnormal joint metabolism in asymptomatic osteochondritic horses.

REASONS FOR PERFORMING STUDY Alternative methods to evaluate the joint condition in asymptomatic osteochondrosis dissecans (OCD) and other joint diseases may be useful. OBJECTIVES To investigate possible changes in synovial fluid composition that may lead to joint conditions in asymptomatic OCD, in mature horses. METHODS Animals aged >2 years, of different breeds, with OCD in the intermediate ridge of distal tibia, symptomatic or not, were studied. Synovial fluid samples (10 healthy; 11 asymptomatic OCD; 25 symptomatic OCD) were collected by arthroscopy from 29 horses. Glycosaminoglycans (GAGs) were analysed by a combination of agarose gel electrophoresis and enzymatic degradation with specific GAG lyases. The viscosity, white blood cell (WBC) count, protein concentration and hyaluronic acid (HA) molecular weight were also determined. RESULTS The method used here to analyse synovial fluid GAGs is reliable, reproducible and specific. The main synovial fluid GAGs are HA and chondroitin sulphate (CS), 93% and 7% respectively in normal horses. In symptomatic OCD, the concentrations of both increased (expressed as GAG/urea ratios), but CS increased more. The CS increased also in asymptomatic OCD. An inflammatory reaction was suggested by the increased WBC counts in OCD. The molecular weight of the synovial fluid HA was reduced in OCD, explaining the lower viscosity observed. CONCLUSIONS The increased CS in synovial fluid of OCD joints in mature horses suggests that the synovial fluid CS and the WBC count are good markers of the joint conditions, allowing the identification of pathological phase in joint diseases. POTENTIAL RELEVANCE The analysis of synovial fluid GAGs shows that cartilage damage occurs even in asymptomatic OCD, implying that arthroscopic removal of osteochondral fragments should be performed even in asymptomatic OCD.

Autologous processed plasma: cytokine profile and effects upon injection into healthy equine joints.

This experimental controlled study was performed to evaluate the composition of autologous processed plasma (APP), and the effects of APP intra-articular injection into healthy equine metacarpophalangeal joints. The effects on joints were analysed with a short-phase protocol and a prolonged-phase protocol using saline-injected joints as controls. For the short protocol, horses received one intra-articular APP injection. Synovial fluid samples were collected prior to the injection and 3, 6, 24, 48, and 16 h after treatment. For the prolonged protocol, the joints received three weekly injections of APP, and samples were collected at 0, 7, 14, 21, and 28 days before APP administration. IL1-ra level was found to be increased in APP compared to plasma. Upon intra-articular administration of APP, transient (up to 24 h) increases in white blood cell (WBC) counts along with elevated protein and prostaglandin E2 (PGE2) concentrations were observed in the treated joints. Over the 28-day observation period, APP did not elicit changes relative to baseline levels, but WBC counts, PGE2 and chondroitin sulphate concentrations were lower than those found in the control. In conclusion, APP intra-articular injection induced a mild and transitory inflammatory response but no inflammation reaction was observed over a longer period of treatment and observation.

Toracoscopia aplicada à ressecção de fragmento pulmonar com o auxílio de sutura mecânica em eqüinos

In this study, a dorsocaudal portion resection of the left caudal lung lobe was performed using an endoscopic stapler by thoracoscopic procedure. Ten healthy horses, eight males and two females were evaluated by clinical examination and submitted to the surgical procedure. The animals were sedated and maintained in standing position. The procedure was done in the left hemitorax using three access previously studied: the first portal was done at the 12th intercostal space (IS); the second one at the 14th, 15th, or 16th IS; and the third one at the 14th or 15th IS, in accordance with the necessity of positioning the instruments. The employed surgical technique seemed to be adequate in all animals, since it helped controlling the existing pneumothorax; furthermore, clinical recovery during the postoperative period was satisfactory, except for one animal. These results suggest that thoracoscopic may successfully be employed for partial lung resection in horses, using endoscopic staplers, and its practical use may contribute to the knowledge and resolution of thoracic diseases.

Endoscópio rígido e flexível na sinoscopia e técnica de triangulação em seios paranasais de equinos

Sinoscopy, the paranasal sinus endoscopy, is a minimally invasive technique used to diagnose and treat sinus disease. The objective of this study was to determine triangulation portals sites from sinoscopy portals previously described and to compare rigid and flexible endoscope of small diameter in horses of different ages. Paranasal sinuses underwent three procedures in sequence: sinoscopy with rigid endoscope, sinoscopy with flexible endoscope and surgical approach to triangulation technique. Rigid endoscope presented higher image quality, although the amplitude of visualization was greater with flexible endoscope that yielded better mobility and proximity of the paranasal sinus anatomical structures. Through frontal sinus portals, the frontal and caudal maxillary sinuses were examined. The structures of maxillary caudal sinus, including the roots of the cheek teeth, were observed through the portal of caudal maxillary sinus. In some animals, the bigger root of the first upper molar teeth, mainly in young horses, made the exam of rostral sinus exam harder. Triangulation portals were determined in frontal and caudal maxillary sinus enabling surgical instrumentation access to anatomical structures. The results enabled the establishment of sinoscopy and triangulation portals to diagnosis and treatment of sinus disease in horses using either flexible or rigid endoscope.