Optimization of iron oxide nanoparticles for MRI-guided magnetic hyperthermia tumor therapy: reassessing the role of shape in their magnetocaloric effect.

Superparamagnetic iron oxide nanoparticles have hogged the limelight in different fields of nanotechnology. Surprisingly, notwithstanding the prominent role played as agents in magnetic hyperthermia treatments, the effects of nanoparticle size and shape on the magnetic hyperthermia performance have not been entirely elucidated yet. Here, spherical or cubical magnetic nanoparticles synthesized by a thermal decomposition method with the same magnetic and hyperthermia properties are evaluated. Interestingly, spherical nanoparticles displayed significantly higher magnetic relaxivity than cubic nanoparticles; however, comparable differences were not observed in specific absorption rate (SAR), pointing out the need for additional research to better understand the connection between these two parameters. Additionally, the as-synthetized spherical nanoparticles showed negligible cytotoxicity and, therefore, were tested in vivo in tumor-bearing mice. Following intratumoral administration of these spherical nanoparticles and a single exposure to alternating magnetic fields (AMF) closely mimicking clinical conditions, a significant delay in tumor growth was observed. Although further in vivo experiments are warranted to optimize the magnetic hyperthermia conditions, our findings support the great potential of these nanoparticles as magnetic hyperthermia mediators for tumor therapy.

Anatomical study of the fibularis longus muscle motor points and electrical stimulation therapy application / Estudio anatómico de los puntos motores del músculo fibularis longus y su aplicación en la terapia de electroestimulación

The fibularis longus muscle (FLM) has an important role in the movement of eversion of the foot and in maintaining the plantar arch. The electrostimulation procedures seek to maintain muscle trophism, increase strength and endurance, and are frequently used in physiotherapy, for which the clinician needs to know the location of the motor points of the FLM. Therefore, the purpose of this study was to determine the number and distribution of motor points of the FLM and relate them to observable parameters in the surface anatomy. Ten formalin-preserved limbs were used, and the lateral regions of the leg were dissected in detail. In all the cases, the muscle presented three fascicular patterns, the superior and anteroinferior fascicles presented two motor points each, while the posteroinferior fascicles were between 2 and 3 motor points. Our results suggest that there is a pattern of distribution of the superficial fibular nerve, whose knowledge is useful for clinical application in the FLM electrostimulation proceedings.

El músculo fibular largo (MFL) tiene una importante función en el movimiento de eversión del pié y en la mantención del arco plantar. Los procedimientos de electroestimulación buscan mantener el trofismo muscular, aumentar la potencia y resistencia y es frecuente su utilización en fisioterapia, para ello el clínico necesita conocer la localización de los puntos motores del MFL, por ello, el propósito de este estudio fue determinar el número y distribución de los puntos motores del MFL y relacionarlos con parámetros observables en la anatomía de superficie. Se utilizaron 10 miembros inferiores conservados y se disecó detalladamente la región lateral de la pierna. El músculo presentó en todos los casos una estructura trifascicular, los fascículos superiores y anteroinferiores presentaron dos puntos motores cada uno, mientras en el fascículo posteroinferior encontramos entre 2 y 3 puntos motores. Nuestros resultados sugieren que existe un patrón de distribución del nervio fibular superficial cuyo conocimiento es de utilidad clínica para los procedimientos de electroestimulación del MFL.