Raquel Yvonne Arantes Baccarin

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.

Lipopolysaccharide-induced inhibition of transcription of tlr4 in vitro is reversed by dexamethasone and correlates with presence of conserved NFκB binding sites.

Engagement of Toll-like receptor 4 (TLR4) by lipopolysaccharide (LPS) is a master trigger of the deleterious effects of septic shock. Horses and humans are considered the most sensitive species to septic shock, but the mechanisms explaining these phenomena remain elusive. Analysis of tlr4 promoters revealed high similarity among LPS-sensitive species (human, chimpanzee, and horse) and low similarity with LPS-resistant species (mouse and rat). Four conserved nuclear factor kappa B (NFκB) binding sites were found in the tlr4 promoter and two in the md2 promoter sequences that are likely to be targets for dexamethasone regulation. In vitro treatment of equine peripheral blood mononuclear cells (eqPBMC) with LPS decreased transcripts of tlr4 and increased transcription of md2 (myeloid differentiation factor 2) and cd14 (cluster of differentiation 14). Treatment with dexamethasone rescued transcription of tlr4 after LPS inhibition. LPS-induced transcription of md2 was inhibited in the presence of dexamethasone. Dexamethasone alone did not affect transcription of tlr4 and md2.

Obstrução nasal por granuloma fúngico em eqüino: relato de caso

A 9-year-old horse presented serosanguineous nasal discharge, absence of breath out through the right nostril, and respiratory noise. Endoscopic and radiographic exams revealed a six centimeter diameter mass, covered by yellowish mucosa, which was obstructing the entire right nasal cavity and part of the left one. The mass was excised through a right frontal sinusotomy. The microscopic exam and the culture revealed a fungic granulomatous rhinitis. Antibiotic and anti-inflammatory drugs were postoperatively administered; moreover, camomile tea and distilled water were flushed in a drain placed above the bone flap.

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.

Patellar instability following experimental medial patellar desmotomy in horses.

A controlled study was designed in order to evaluate the effects of medial patellar desmotomy (MPD), combined with exercise restriction, on clinically and radiographically normal femoropatellar joints, and to identify the patellar instability by radiographic examination. MPD was performed on the right hind limb and the horses were rested for 120 days. Both hind limbs were radiographed before surgery and at 15, 30, 60, 90, and 120 days after MPD, obtaining lateromedial, flexed lateromedial, caudocranial and cranioproximal-craniodistal (skyline) views. The femorotibial and femoropatellar angles were assessed on the lateromedial views, and the distance between the medial and lateral cortex of the femur, and the distance between the medial cortex of the femur and the lateral border of the patella were evaluated in the caudocranial views. An increase in the angle between the proximal articular surface of the patella and the cranial distal surface of the femur along with enthesophyte formation and lateral deviation of the patella were found on the radiographs of the right stifles after MPD. Therefore, MPD leads to patellar instability, which can be demonstrated by the radiographic changes. The 120 days rest did not prevent the lesions caused by postsurgical patellar instability.

Appropriate secondary absolute erythrocytosis in a horse

ERYTHROCYTOSIS is an increase in red blood cell (RBC) count. Relative erythrocytosis, as caused by dehydration-related haemoconcentration or splenic contraction, is more common (Watson 2000) than absolute erythrocytosis, in which there is an actual increase in the number of RBCs. Absolute erythrocytosis can be primary or secondary (Lording 2008) and is uncommon in horses (Munoz and others 2009, Sellon and Wise 2010). Primary erythrocytosis is characterised by a proliferation of cells of the erythroid lineage without an increase in erythropoietin (Collatos 2003). Secondary erythrocytosis involves an increase in erythropoietin and can be appropriate (in response to tissue hypoxaemia), as in congenital cardiovascular disease, severe chronic pulmonary or cardiovascular conditions, high altitude or changes in haemoglobin (Watson 2000, Thrall 2004), or inappropriate. Inappropriate erythrocytosis involves the release of erythropoietin or erythropoietin-like substances in response to renal hypoxia or neoplasia (Lennox and others 2000, Thrall 2004, Koch and others 2006). If the haematocrit rises above 60 per cent, the advantages of greater oxygen transport are overcome by the harmful effects of increased blood viscosity (Watson 2000, Thrall 2004). In horses, the most prominent clinical signs are lethargy, weight loss, dark-coloured blood, deep red to purple mucous membranes, normal to slightly elevated capillary refill time, tachycardia and tachypnoea, mild cyanosis, haemorrhagic episodes and thrombosis (McFarlane and others 1998, Watson 2000, Collatos 2003, Thrall 2004, Sellon and Wise 2010). Congenital cardiac anomalies are the main cause of absolute erythrocytosis in large animals. Erythrocytosis …

Ocorrência de neoplasias em 15 anos de atendimento hospitalar de equídeos

Although several prior studies have provided information regarding incidence of tumors in horses, there is a wide variation due to regional differences, such as climate and breed population. A number of 133 cases involving tumors was found among the 6669 equides submitted to the Veterinary Hospital (HOVET) of the School of Veterinary Medicine of the University of Sao Paulo, during a 15 years period, representing 2% of all records. The most commonly found neoplasm was the squamous cells carcinoma (45%), different from most of the studies worldwide. The most common neoplasia in the integument system was melanoma (34,2%) and in the ocular (76,9%) and urogenital systems (40,9%) was squamous cells carcinoma. Surgical intervention was recommended in 68% of the cases, while a clinical approach was chosen in 10% of them. Twenty two percent of the horses were not treated due to of the owner option or euthanasia indication. Death associated with tumors occurred on 14% of the animals during the hospitalization period or treatment. The squamous cell carcinoma occurs more often in our veterinary hospital and may be related to prolonged exposure to ultraviolet radiation, whose amount in the tropics has increased considerably in the last decades.

Líquido sinovial da articulação femuropatelar após desmotomia patelar medial experimental em eqüinos

Medial patellar desmotomy (MPD) is a common treatment for upward fixation of the patella (UFP). It is easy to perform, and in most cases results are immediate. However, joint changes after MPD have been described. The purpose of this study is to use synovial fluid evaluate the effects of MPD in horses subjected to restricted exercis in the first 120 days postoperatively. Eight sounds adult horses, weighing from 350 to 480kg, were used in the study. The selected animals had no history of lesions in the femuropatellar joint and did not demonstrate lameness on physical examination or after hind limb flexion tests. Right medial patellar desmotomy was performed on each horse. The synovial fluid was obtained by arthrocentesis during the selection phase and after surgery on days 15, 30, 60, 90 and 120. Synovial fluid color, viscosity, total protein, and nucleated cell count and diferential leukocyte count was analysed. The poor viscosity on day 30 was the highest significative change from synovial fluid on the horses subject to medial patelar desmotomy and maintened in rest for 120 days.

Do blood components affect the production of reactive oxygen species (ROS) by equine synovial cells in vitro

Blood-derived products are commonly administered to horses and humans to treat many musculoskeletal diseases, due to their potential antioxidant and anti-inflammatory effects. Nevertheless, antioxidant effects have never been shown upon horse synovial fluid cells in vitro. If proved, this could give a new perspective to justify the clinical application of blood-derived products. The aim of the present study was to investigate the antioxidant effects of two blood-derived products - plasma (unconditioned blood product - UBP) and a commercial blood preparation (conditioned blood product - CBP)1 - upon stimulated equine synovial fluid cells. Healthy tarsocrural joints (60) were tapped to obtain synovial fluid cells; these cells were pooled, processed, stimulated with lipopolysaccharide (LPS) or phorbol 12-myristate 13-acetate (PMA), and evaluated by flow cytometry for the production of reactive oxygen species (ROS). Upon addition of any blood-derived product here used - UBP and CBP - there was a significant decrease in the oxidative burst of synovial fluid cells (P<0.05). There was no difference between UBP and CBP effects. In conclusion, treatment of stimulated equine synovial cells with either UBP or CBP efficiently restored their redox equilibrium.

The cross-sectional area of the superficial digital flexor tendon of trained and untrained Thoroughbred racehorses

Twenty Thoroughbred racehorses were ultrasonographically evaluated to determine the relation between normal values of the cross-sectional area (CSA) of the right and left forelimbs superficial digital flexor tendons (SDFT) in the metacarpal region for trained and untrained Thoroughbreds racehorses. Ultrasonography revealed that CSA at 26cm distal to the accessory carpal bone is larger than other proximal levels, for either left or right forelimbs. In addition, the CSA at 2, 4, 6, 8, 10, 12 and 14cm distal to the accessory carpal bone of the left forelimb are larger (P 0.05) between left and right forelimb for CSA of the SDFT, at any level, for either trained or untrained horses, and there was no significant difference between untrained or trained horses for the CSA of right forelimb. In conclusion, the CSA of the left forelimb SDFT for horses that had been in continuous race training remains larger when they were trained anticlockwise, contrary to horses that had not been training for more than one year.