RESUMEN
The World Health Organization has approved magnetic nanoparticles (MNP) for use as a contrast agent for magnetic resonance imaging or tumor hyperthermia treatment. MNP are toxic over time after intra-testicular injection. A clear strategy to ameliorate the toxic side effects of MNP in normal tissues after medical application has not yet been developed. We used an extract of Echinacea purpurea (EP) as a natural source of antioxidant and free radical scavenging product for detoxification of MNP in testicular tissues. MNP localization in the interstitial area of testicular tissue reduced the expression of insulin-like factor 3 (INSL3) proteins as well as serum testosterone levels. Further, MNP caused accumulation of both collagen and elastin in the interstitial area and increased the thickness of the tunica albuginea. Injection of MNP during administration of EP extract for short periods slightly reduced the toxic side effects of MNP. After extended exposure to EP extract, INSL3 expression and testosterone returned to near control levels. Also, collagen and elastin accumulation caused by MNP was reduced after extended exposure to EP extract. We believe that the ameliorative effect of EP extract is due to its antioxidant properties.
Asunto(s)
Echinacea/química , Fibrosis/inducido químicamente , Regulación de la Expresión Génica/efectos de los fármacos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Nanopartículas de Magnetita , Extractos Vegetales/farmacología , Testículo/efectos de los fármacos , Animales , Fibrosis/tratamiento farmacológico , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Masculino , Microscopía Electrónica de Transmisión , Extractos Vegetales/química , Ratas , Testículo/patología , Testosterona/metabolismoRESUMEN
The objectives of this study are twofold. First, to further develop the understanding of the relationship between the observed mechanical response and changes in the crimp pattern in human patellar tendon bone units. This is accomplished through the use of a specially constructed test frame and microscope system that permits observation and measurement of the crimp patterns as a function of load. Second, the results of the experimental study are used to develop a constitutive equation that includes spatial variation in the crimp pattern. The results of both the experimental and analytical study imply that local strain in the proximity of the attachment site is significantly larger than the strain in the central region of the tendon. The experimental and histological results are for specimens taken from four human bone-patellar tendon-bone units.