Biomodelo para la docencia de grado y postgrado en pediatría / Biomodel for teaching undergraduate and graduate in pediatrics

Introducción: La incorporación de la Clínica y la Imagenología permiten una mejor comprensión de la Anatomía. El objetivo de este trabajo es desarrollar un prototipo rápido en material sintético que replique detalles anatómicos para ser utilizado en la docencia de grado y postgrado en Pediatría. Material y Método: Caso 1: Niña de 1 año de edad con síndrome de dificultad respiratoria a causa de una malformación vascular. Caso 2: recién nacido con malformación torácica. Con la finalidad de analizar una conducta adecuada, se solicitó la confección de un prototipo rápido a escala 1:1 que simulara una condición idéntica a la topografía torácica del paciente, utilizando imágenes virtuales 3D almacenadas en formato DICOM.Técnica de generación de prototipo rápido: Se obtuvouna malla digital tridimensional y se generó el código “g”que se utilizó para controlar el hardware de producción. Se efectuó simulación digital y producción en material plástico (ABS) con técnica de deposición y fusión (MDF).Se validó el prototipo comparándo lo con las mediciones testigos del modelo virtual en 3 D.Resultados y Discusión: El modelo replicó exactamente los defectos hallados en la tomografía y endoscopía, confirmando la presencia de la malformación vascular y su repercusión sobre el aparato respiratorio. El prototipo rápido muestra las estructuras internas y externas del cuerpo humano con máxima precisión permitiendo una visión topográfica de situaciones “normales o patológicas” que facilitaría la docencia y el entrenamiento del equipo quirúrgico para proponer un plan de tratamiento adecuado. Hay numerosas áreas de la medicina que sebeneficiarían con este modelo que podría ser construído con diversos tipos de materiales de diferente flexibilidad y consistencia. Conclusiones: El prototipo rápido le da estado físico a las imágenes virtuales 3D, permitiendo la docencia y entrenamiento del equipo quirúrgico.

Introduction: The incorporation of the clinic and the imaging allow a better understanding of anatomy. Theaim of this work is to develop a rapid prototype in synthetic material that replicates anatomical details to be used inteaching and surgical training in Pediatrics. Material and method: Case 1: one year old female with respiratory distress syndrome because of vascular malformation. Case 2: newborn patient with thoracic malformation. In order to discuss appropriate conduct, the making of rapid prototyping in scale 1:1 was requested to simulate an identical condition of the thoracic topography of the patients, using virtual 3D images stored in the DICOM format. Rapid prototype technique: code "g" was generated, which was used to control the hardware of production and a three-dimensional digital grid was obtained. Digital simulation and production in plastic (ABS) with deposition and fusion technique (MDF) was performed. The prototype was validated by comparing measurements with witnesses of the virtual model in 3 D. Results and discussion: the model replied exactly the defects found in the scan and endoscopy, confirming the presence of vascular malformation and its impact on the respiratory system. Rapid prototype shows the internal and external structures of the human body with maximum precision allowing a topographic view of "normal or pathological" situations that would facilitate the teaching and training of the surgical team to propose an appropriate treatment plan. There are many areas of medicine that would benefit from this model that couldbe built with different types of materials with different flexibility and consistency. Conclusions: Rapid prototype gives form to virtual 3D images, allowing teaching and training of the surgical team.

Reperfusion damage to the bile canaliculi in transplanted human liver.

In 19 patients who have undergone orthotopic liver transplantation (OLT), the trend and degree of cholestasis was statistically monitored in terms of plasma levels of L-gamma-glutamyl transferase (GGT) and total bilirubin. In addition, the ultrastructure of the bile canaliculus was examined during the entire OLT procedure, i.e., during explantation, cold ischemia, and after 60 to 90 minutes of organ reperfusion. Cholestasis was evident from the second day after surgery, with a peak after approximately 10 to 16 days. Defined, small changes in the functional state of actin filaments were noted in the bile canalicular area after prolonged ischemia. But the morphological status of the bile canaliculi changed dramatically after reperfusion. In fact, the mean area and perimeter of the canaliculi had increased significantly, and there was a marked loss in the number of bile microvilli per unit of canalicular area. The bile canaliculus appears to be one of the liver structures most susceptible to ischemia-reperfusion damage. A series of biochemical changes occurring during ischemia and after reoxygenation of the transplanted liver, especially, would provide a reason for the observed early morphological damage of the bile canaliculus, which, in turn, would explain the cholestasis of these patients in the first posttransplantation period.

Oxidative damage in human liver transplantation.

The aim of this study was to evaluate oxygen-dependent hepatic reperfusion injury in humans following orthotopic liver transplantation. To this end, a number of blood indices of impaired tissue redox balance were monitored in 19 adult patients for 3 weeks after liver transplantation. Both red cell malonaldehyde and plasma lipid peroxides increased significantly soon after organ reperfusion. This finding was consistently accompanied by decreased plasma vitamin E and red cell total glutathione. A peak of oxidative stress, as measured by the parameters monitored, was evident within 24 h after reperfusion, together with a maximum expression of cytolysis, as measured by plasma alanine aminotransferase. The occurrence of redox imbalance after hepatic reperfusion was shown to be linearly related to irreversible cell damage. As regards the low plasma levels of the two antioxidants after reperfusion, only that of vitamin E appeared statistically related to oxidative stress. With the background of an increasing body of proof, mainly from animal models, the involvement of toxic oxygen metabolites in hepatic cytolysis following orthotopic liver transplantation appears likely. The statistical correlation among the markers of redox imbalance monitored indicates their combined use in further investigation.

[Drug therapy and enteral hyperalimentation in the prevention of stress ulcer in intensive therapy]. / Trattamento farmacologico ed alimentazione enterale nella prevenzione dell'ulcera da stress in terapia intensiva.

Stress ulcer is one of the risks to which patients undergoing intensive therapy are exposed. In an attempt to gain further knowledge on the ways and means of preventing this complication, a comparison was made of a selective treatment using drugs with a specific action on the gastric mucosa in a series of 20 cases. The clinical course was compared with that observed in 20 untreated patients. Drug management was associated with continuous and constant enteral alimentation to keep the activity of the digestive apparatus as physiological as possible.

[Paraquat poisoning. Clinical and anatomo-pathological aspects]. / Avvelenamento da Paraquat. Aspetti clinici ed anatomo-patologici.

Two cases of Paraquat poisoning of anticonservative origin are described. A brief account of the chemical composition and mechanism of action of Paraquat is followed by a discussion of the clinical and therapeutic features of the two cases. The anatomopathological findings obtained from lung specimens examined during necropsy are also described. Personal experience and the literature data are cited in an explanation of what is currently regarded as the most effective treatment protocol.

[Current treatment of tetanus patients in intensive therapy]. / Trattamento attuale del tetano in terapia intensiva.

A brief survey of recent criteria for evaluation of the seriousness of toxicity and infection in tetanus is followed by the examination of a series of cases of average severity. The method employed in their therapeutic management is described, and an account is given of its advantages and the possibility of complications. The mortality rate for the years 1974-1978 is also reported.