Effect of ascorbic acid and epidermal growth factor in a rat tibia defect

Purpose: Bone repair aims to restore the anatomical, biomechanical, and functional integrity of the affected structure. Here we study the effects of ascorbic acid (AA) and epidermal growth factor (EGF) applied in a single dose and in combination on the repair of a noncritical bone defect model. Methods: Twenty-four rats were divided into four groups: an intact G-1 control group, and three groups that underwent a noncritical bone defect in the right tibia: G-2 treated with AA, G-3 treated with EGF, and G-4 treated with AA in combination with EGF. After 21 days of treatment, rats were sacrificed, the tibias were dissected and a destructive biomechanical analysis of three-point flexion test was performed in a universal testing machine; the values of stiffness, resistance, maximum energy, and energy at maximum load were statistically compared. Results: G-3 and G-4 recovered the biomechanical properties of strength and stiffness of an intact tibia 3 weeks after their application. Not so the energy and energy at maximum load. For G-2, only the stiffness of an intact tibia was recovered. Conclusion: EGF and AA-EGF applied to a noncritical bone defect in the rat tibia favors the recovery of bone resistance and stiffness.

A castor oil plant (Ricinus communis)-derived implant improves the biomechanical properties of noncritical bone defects

ABSTRACT Purpose The biomechanical properties of the polyurethanes implant material derived from castor oil plant (Ricinus communis) were evaluated in a noncritical bone defect model in rat tibia. Methods After three weeks of the implant application, the tibias were tested by means of the biomechanical three-point flexion test and resistance, rigidity, energy at maximum load and maximum energy were evaluated. Nonparametric statistical analysis was performed. Results It was found that the group that received the implant behaved the same as the intact control group and also showed a significant increase in maximum load compared to the spontaneous repair group. Conclusions Our results indicate that the tibias with the implant material in a noncritical bone defect recover normal biomechanical parameters in less time than spontaneously.

Anomalía de "apple-peel": consideraciones etiopatogénicas a propósito de dos observaciones / \"Apple-peel\" anomaly: ethiopathogenical considerations apropos of 2 cases

Se presentan dos recién nacidos afectos de anomalía intestinal tipo "apple-peel". El primer paciente, recién nacido a término con retraso del crecimiento intrauterino y fenotipo de síndrome por alcoholismo fetal, asociaba una estenosis hipertrófica de píloro con malrotación intestinal. El segundo enfermo, un recién nacido pretérmino de peso adecuado, de 1,400 g, presentaba asociada: atresia duodenal, consanguinidad entre sus progenitores y el antecedente de un hermano intervenido al nacimiento por diafragma duodenal incompleto. Ambos fueron intervenidos quirúrgicamente en el octavo y segundo día de vida respectivamente, siendo su evolución favorable. Tras el análisis de nuestras observaciones, realizamos una revisión de los mecanismos etiopatogénicos hipotéticos implicados directamente en la anomalía intestinal en "piel de manzana"

Trisomía parcial del cromosoma 1.46,XX dir. dup (1q) (q32- q44) / Partial trisomy 1q

Se aporta la observación de un caso de trisomía 1q parcial asociada a manifestaciones fenotípicas y anatomopatológicas propias de la anomalía de Di George. La variable expresión de la misma parece correlacionarse con distintas circunstancias asociadas, que se interpretan como causantes de la mencionada anomalía. Los autores establecen la relación entre cromosomopatía y alteración fenotípica, sugiriendo la obligatoriedad del estudio citogenético de aquellos cuadros que clínicamente correspondan a los distintos grados de síndrome de Di George