Evaluation of the effect of experimentally induced cartilage defect and intra-articular hyaluronan on synovial fluid biomarkers in intercarpal joints of horses.

BACKGROUND: Inflammatory and degenerative activity inside the joint can be studied in vivo by analysis of synovial fluid biomarkers. In addition to pro-inflammatory mediators, several anabolic and anti-inflammatory substances are produced during the disease process. They counteract the catabolic effects of the pro-inflammatory cytokines and thus diminish the cartilage damage. The response of synovial fluid biomarkers after intra-articular hyaluronan injection, alone or in combination with other substances, has been examined only in a few equine studies. The effects of hyaluronan on some pro-inflammatory mediators, such as prostaglandin E2, have been documented but especially the effects on synovial fluid anti-inflammatory mediators are less studied. In animal models hyaluronan has been demonstrated to reduce pain via protecting nociceptive nerve endings and by blocking pain receptor channels. However, the results obtained for pain-relief of human osteoarthritis are contradictory. The aim of the study was to measure the synovial fluid IL-1ra, PDGF-BB, TGF-ß1 and TNF-α concentrations before and after surgically induced cartilage defect, and following intra-articular hyaluronan injection in horses. Eight Standardbred horses underwent bilateral arthroscopic surgeries of their intercarpal joints under general anaesthesia, and cartilage defect was created on the dorsal edge of the third carpal bone of one randomly selected intercarpal joint of each horse. Five days post-surgery, one randomly selected intercarpal joint was injected intra-articular with 3 mL HA (20 mg/mL). RESULTS: Operation type had no significant effect on the synovial fluid IL-1ra, PDGF-BB, TGF-ß1 and TNF-α concentrations but compared with baseline, synovial fluid IL-1ra and TNF-α concentrations increased. Intra-articular hyaluronan had no significant effect on the biomarker concentrations but a trend of mild improvement in the clinical signs of intra-articular inflammation was seen. CONCLUSIONS: Creation of the cartilage defect and sham-operation lead to an increase of synovial fluid IL-1ra and TNF-α concentrations but changes in concentrations of anabolic growth factors TGF-ß1 and PDGF-BB could not be documented 5 days after the arthroscopy. Intra-articular hyaluronan was well tolerated. Further research is needed to document possible treatment effects of intra-articular hyaluronan on the synovial fluid biomarkers of inflammation and cartilage metabolism.

Platelets promote mitochondrial uncoupling and resistance to apoptosis in leukemia cells: a novel paradigm for the bone marrow microenvironment.

Here we report that leukemia cell lines and primary CD34+ leukemic blasts exposed to platelet rich plasma (PRP) or platelet lysates (PL) display increased resistance to apoptosis induced by mitochondria-targeted agents ABT-737 and CDDO-Me. Intriguingly, leukemia cells exposed to platelet components demonstrate a reduction in mitochondrial membrane potential (ΔΨM) and a transient increase in oxygen consumption, suggestive of mitochondrial uncoupling. Accompanying the ranolazine-sensitive increase in oxygen consumption, a reduction in triglyceride content was also observed in leukemia cells cultured with platelet components indicating that lipolysis and fatty acid oxidation may support the molecular reduction of oxygen in these cells. Mechanistically, platelet components antagonized Bax oligomerization in accordance with previous observations supporting an antiapoptotic role for fatty acid oxidation in leukemia cells. Lastly, substantiating the notion that mitochondrial uncoupling reduces oxidative stress, platelet components induced a marked decrease in basal and rotenone-induced superoxide levels in leukemia cells. Taken together, the decrease in ΔΨM, the transient increase in ranolazine-sensitive oxygen consumption, the reduction in triglyceride levels, and the reduced generation of superoxide, all accompanying the increased resistance to mitochondrial apoptosis, substantiate the hypothesis that platelets may contribute to the chemoprotective sanctuary of the bone marrow microenvironment via promotion of mitochondrial uncoupling.

Osteosarcoma generalizado y megaesófago secundario, ocasionados por infección de Spirocerca lupi en un canino / Generalized osteosarcoma and secondary megaesophagus caused by Spirocerca lupi in a dog

En este artículo se describe un caso clínico poco frecuente de osteosarcoma generalizado acompañado de megaesófago secundario adquirido, ocasionados por un granuloma parasitario torácico de Spirocerca lupi, en un canino bóxer adulto. Se presentan los hallazgos radiológicos y anatomo-patológicos y se discuten con la literatura revisada.

Artrodesis antebraquiocarpiana e intercarpiana como tratamiento quirúrgico de una lesión ocasionada por hiperextensión del carpo en un perro / Antebraquialcarpal and carpocarpal atrhrodesis as a surgical treatment of a injury produced by carpal hyperextension in a dog

En este artículo se describe un caso clínico de subluxación parcial del carpo derecho (antebraquiocarpiana e intercarpiana) de un canino de 14 meses de edad. Se discute el diagnóstico, tratamiento médico-quirúrgico, rehabilitación física y se comparan los resultados obtenidos con la literatura.

Megaesófago idiopático congénito canino. Reporte de un caso / Canine idiopathic congenital megaesophagus. A case report

En este articulo se reporta un caso de megaesófago idiopático congénito en un cachorro caniche de dos meses de edad. Se muestran detalladamente las alteraciones anatómicas observadas en el estudio radiológico con medio de contraste positivo (sulfato de Bario). Se hace una revisión de literatura sobre esta anomalía y se comparan las alteraciones patológicas del paciente de este estudio con la literatura internacional.