Effect of ofloxacin on the cartilage of the knee joint of juvenile rats

Ofloxacin is one of fluoroquinolones derivatives, which has a broad spectrum bacterial activity. It is contraindicated in children and adolescents because of its potential chondotoxicity in juveniles. However, fluoroquinolones continue to be prescribed as a drug of choice for treatment of some life threatening diseases in pediatrics. This study was conducted to examine the effect of ofloxacin on cartilage of juvenile rats by light and electron microscopes. Twenty newborn albino rats were treated with an oral dose of 900 mg/kg/day of ofloxacin for 28 days. The animals were sacrificed after the completion of the administration and the knee joints were prepared for light and electron microscopic examination. Morphometric study and statistical analysis of the results were also performed. The lesions were demonstrated in the articular cartilage of all the animals. Fissures, chondrtocyte clusters and wide area of matrix devoid of cells in the intermediate zone were observed. The surface of the premature articular cartilage of the femur was irregular. The matrix of the articular cartilage showed less staining with toluidine blue and masson trichrome. Electron microscopic results showed separation between chondrocyte cell membrane and the matrix. The chondrocytes were necrotic with pyknotic nuclei and vacuolation of their cytoplasm. There were electron dense aggregates on the cell membrane and inside the cells. The thickness of the premature articular cartilage and epiphyseal plate cartilage were significantly decreased. The numbers of chondrocytes of the premature articular cartilage and epiphyseal plate cartilage were significantly decreased. The numbers of chondrocytes of the premature articular cartilage and epiphyseal plate cartilage were significantly decreased

Histochemical study of developing cartilage of the primordial vertebrae in rat embryo

The aim of this study was to investigate the presence anddistribution of cell surface terminal sugars in developing cartilage of theprimordial vertebrae in rat embryo. Material and Fifty female and 25 male Wistar rats were chosenrandomly. After adaptation, mating was done. Vaginal plug observationwas performed on O-day of gestation. Specimens were collected from9-18 days old embryos and were fixed in B4G solution. After routinehistological processing and embedding in paraffin, blocks were cut into4-micrometer thickness sections. Then sections were stained byPAS-Alcian blue and Lectin histochemistry methods [VVA-B4, MPA, WFA].On the basis of intensity of staining, sections were graded andnonparametric statistical test [Kruskal Wallis] was used to comparedifferences between samples. The commencment of chondroblast differentiation in the centrumof future vertebrae was specified by appearance of D-Gal Terminal sugarin 13th day of embryonic period. On the 14th to 16th days of presence ofGal/GalNac, D-GalNac terminal sugars were detected in developingvertebrae. Reactions were first observed in centrum and then in pediclesand laminae of vertebrae. From the 17th day on ward, reaction with theabove mentioned lectins showed a significant reductions [P<0.05]. This study showed that changes in surface terminal sugarsregulate morphologic changes and the fate of the cell, during tissuegrowth and development

Cartílago normal y patológico / Normal and pathological articular cartilage

El cartílago articular es el tejido responsable de la lubricación y rigidez compresiva de las articulaciones durante el movimiento, gracias a sus propiedades de viscoelasticidad a la carga mecánica. Sin embargo, una vez dañado tiene una capacidad limitada o mínima de curación y a menudo evoluciona a cambios patológicos degenerativos. Debido a lo anterior se hace necesario revisar las ciencias básicas para comprender mejor el rol que éste cartílago articular juega durante éste proceso reparativo. Este artículo fue escrito en un esfuerzo para mejorar nuestra comprensión del proceso curativo del cartílago articular