Assessment of engineered surfaces roughness by high-resolution 3D SEM photogrammetry.

We describe a methodology to obtain three-dimensional models of engineered surfaces using scanning electron microscopy and multi-view photogrammetry (3DSEM). For the reconstruction of the 3D models of the surfaces we used freeware available in the cloud. The method was applied to study the surface roughness of metallic samples patterned with parallel grooves by means of laser. The results are compared with measurements obtained using stylus profilometry (PR) and SEM stereo-photogrammetry (SP). The application of 3DSEM is more time demanding than PR or SP, but it provides a more accurate representation of the surfaces. The results obtained with the three techniques are compared by investigating the influence of sampling step on roughness parameters.

Cirugía percutánea de la litiasis renal en la era de la litotripsia extracorpórea: experiencia en 301 pacientes / Percutaneous renal surgery: experience in 301 patients

Introduction: Percutaneous renal surgery was introduced more than 20 years ago in urological practice. Extracorporeal Shock Wave Lithotripsy (ESWL) enter the urological scene shortly after. Our objective is to show our experience in percutaneous renal surgery after the introduction of the ESWL in our institution. Material and Methods: Surgical outcomes of 301 patients who underwent percutaneous renal surgery as treatment of renal stones were analyzed. This series begins just before the introduction of ESWL in our unit. Results: Renal pelvis was the most frequent localization with 142 cases (47.2 percent). There were 51 patients with straghorn calculi. 255 (84.7 percent) were stone free after one single procedure. Residual fragments were managed with many methods, until only 16 patients (5.4 percent) had residual fragments. Complications occurred in 26 patients (8.9 percent). There was no mortality. Conclusions: Percutaneous surgery is an important tool in the management of renal stones. In general, renal stones managed with this procedure, are more complex, however the achievement of good results is possible.

Introducción: La cirugía percutánea (CP) de la litiasis renal fue introducida en la urología hace más de 20 años. Poco después lo hizo la litotripsia extracorpórea (LEC). Nuestro objetivo es mostrar la experiencia en CP luego de la introducción de la LEC en nuestro servicio. Material y Métodos: Se analizan en forma retrospectiva los resultados de 301 pacientes operados por CP por litiasis renal. La serie comienza con la adquisición de un litotriptor extracorpóreo en nuestro servicio. Resultados: La localización más frecuente fue la pelvis renal con 142 casos (47,2 por ciento). Se observó litiasis coraliforme en 51 pacientes. Doscientos cincuenta y cinco (84,7 por ciento), quedaron libres de litiasis con un procedimiento. La litiasis residual fue tratada con diversos métodos, para un total final de 16 pacientes con fragmentos residuales (5,4 por ciento). Ocurrieron complicaciones en 26 pacientes (8,9 por ciento). No hubo mortalidad. Conclusiones: La cirugía percutánea de la litiasis renal es un procedimiento que debe formar parte importante en la resolución de la litiasis renal. En general las litiasis tratadas son más complejas, sin embargo, los resultados son excelentes.

Nefrectomía simple laparoscópica NOTES y LESS con el uso de instrumentos laparoscópicos estándar: experiencia inicial en 3 casos / NOTES and LESS laparoscopic simple nephrectomy with the use of standard laparoscopic instruments: initial experience in 3 cases

Introduction: Natural orifice transluminal endoscopic surgery (NOTES) and Laparoendoscopic Single Site Surgery (LESS) are emerging technologies, which allows to performed surgical procedures avoiding any surgical scars. However there are some problems due to the lack of equipment available for these procedures. The aim of these study is to present our initial experience with the transvaginal nephrectomy NOTES and LESS using standard laparoscopic instruments. Material and Methods: Two female patients (23 and 26 years old) with diagnosis of recurrent urinary tract infection and renal atrophy. A laparoscopic simple nephrectomy with transvaginal NOTES assistance was performed, using one access port for the camera and two abdominal work ports of 10 and 3mm. In a third patient (15 years old) a transumbilical LESS nephrectomy was preformed with the use of standard laparoscopic instruments. Results: Average operative time was 110 min (40-200), with an estimated blood loss of 200 cc. There were no perioperative complications and all patients were discharged 36 hours after surgery. Conclusion: Laparoscopic simple nephrectomy with transvaginal NOTES assistance and LESS are technically feasible with the use of standard laparoscopic instruments. Special access trocars and instruments development for this procedure will allow to performed a pure technique without the use of abdominal incisions.

Introducción: La cirugía endoscópica transluminal a través de orificios naturales (NOTES) y la cirugía laparoendoscópica a través de sitio único (LESS) son tecnologías emergentes, que permiten realizar procedimientos quirúrgicos minimizando el uso de incisiones abdominales. Sin embargo, existen limitaciones respecto al equipamiento disponible para simular la cirugía tradicional. Nuestro objetivo es presentar nuestra experiencia con la técnica de nefrectomía laparoscópica NOTES y LESS con el uso de instrumentos laparoscópicos estándar. Materiales y Métodos: Dos pacientes de sexo femenino de 23 y 26 años, ambas con diagnóstico de infecciones urinarias recurrentes y atrofia renal secundaria. Se les realizó una nefrectomía simple con asistencia de NOTES, utilizando un puerto de trabajo transvaginal para la cámara y dos puertos adicionales de 10 (umbilical) y 3 mm en el abdomen. Un tercer paciente de sexo masculino de 15 a±os de edad, fue operado a través de la técnica LESS por vía transumbilical con el uso de cistoscopio flexible e instrumentos laparoscópicos estándar. Resultados: La media del tiempo operatorio fue de 110 min (40-200), la pérdida sanguínea promedio fue de 133 cc (0-200). No se reportan complicaciones, siendo todos los pacientes dados de alta antes de 36 horas. Conclusión: La nefrectomía laparoscópica con asistencia de NOTES y LESS es técnicamente posible con el uso de instrumentos laparoscópicos estándar. El desarrollo y acceso a trócares y pinzas especiales, permitirá realizar una técnica pura sin el uso de incisiones abdominales.

Morbilidad de la linfadenectomía lumboaórtica laparoscópica en pacientes con tumor testicular no seminomatoso en estadío clínico A / Operative morbidity in laparoscopic retroperitoneal lymph node disection in clinical stage A non-seminomatous testis cancer

Background: Retroperitoneal Lymph node dissection is part of the treatment of patients with nonseminomatous germ cell tumors stage I (NSGCT). Aim: To report the immediate surgical outcomes of patients subjected to laparoscopic retroperitoneal lymph node dissection. Material and Methods: Prospective analysis of the surgical outcomes of 118 patients aged 15 to 44 years, who underwent Laparoscopic Retroperitoneal Lymph Node Dissection (L-RPLND) for NSGCT stage I. Results: Median blood loss was 50 cc (range 10-1.000 cc), median operative time was 120 min. (range 60-300 min). Mean hospital stay was 41.4 hours. Twelve patients (10.2 percent) had operative complications. Ten had vascular injuries (8.5 percent), one had a duodenal injury (0.85 percent) and one had an acute pulmonary edema (0.85 percent). Eight lesions were repaired laparoscopically and three required conversion to open surgery. There was no mortality in this series. Conclusions: L-RPLND had an acceptable complication rate in this series of patients. Most of the complications could be resolved laparoscopically.

Introducción: La linfadenectomía retroperitoneal lumboaórtica es el método de elección en el tratamiento de los pacientes con cáncer testicular no seminoma en estadio A. Este trabajo muestra los resultados inmediatos de una serie de 118 pacientes operados por vía laparoscópica. Material y Método: Se analizan los resultados quirúrgicos de 118 pacientes portadores de un cáncer testicular no seminoma estadio clínico A. Resultados: La media de edad fue de 29 años. La mediana de sangrado fue de 50 cc, el tiempo quirúrgico tuvo una mediana de 120 minutos y el tiempo de hospitalización tuvo una media de 41,4 horas. Complicaciones intraoperatorias ocurrieron en 12 pacientes (10,2 por ciento): 10 lesiones hemorrágicas (8,5 por ciento), 1 lesión duodenal (0,85 por ciento) y 1 edema pulmonar agudo (0,85 por ciento). De las 11 lesiones quirúrgicas, 8 fueron reparadas por vía laparoscópica, requiriendo conversión a cirugía abierta 3 casos. No hubo mortalidad en la serie. Conclusiones: La linfadenectomía lumboaórtica laparoscópica es un procedimiento estandarizado, con una tasa de complicaciones aceptable, la mayoría de las cuales puede ser resuelta en forma laparoscópica.

Incidences of polluting episodes in sedimentary media.

There exist diverse radioactivity sources in the environment coming from anthropogenic activities that alter the natural levels of radiation. The detailed study of the environmental impact of these sources is of great interest, because it provides knowledge for subsequent decontamination works and environmental control. In this work, it is analyzed the radioactive contamination caused by the radionuclide (226)Ra in sedimentary media under a liquid sheet. In this way, the dumping of the radionuclide in sediment columns has been studied in laboratory, determining how its penetration in depth develops along time and for different grain sizes. For this purpose, a migration model based on the numeric resolution of the diffusion equation has been devised.

A new generation of bio-derived ceramic materials for medical applications.

A new generation of bio-derived ceramics can be developed as a base material for medical implants. Specific plant species are used as templates on which innovative transformation processes can modify the chemical composition maintaining the original biostructure. Building on the outstanding mechanical properties of the starting lignocellulosic templates, it is possible to develop lightweight and high-strength scaffolds for bone substitution. In vitro and in vivo experiments demonstrate the excellent biocompatibility of this new silicon carbide material (bioSiC) and how it gets colonized by the hosting bone tissue because of its unique interconnected hierarchic porosity, which opens the door to new biomedical applications.

Diffusion of (226)Ra and (40)K radionuclides reproduced in underwater sedimentary columns in laboratory.

The potential radiological impact of the increase of radioactive substances in the environment makes interesting the study of the migration of the contaminant radionuclides in soils and sediments, which are the last receiver system of these substances. By using a battery of sedimentary columns controlled in the laboratory, the diffusion of the (226)Ra and (40)K radionuclides has been studied, assessing their respective effective diffusion coefficients in a similar sedimentary medium. A decreasing temporal evolution is obtained, associated to the progressive 'fixation' of the radionuclides by the clay minerals of the sediment, followed by a constant tendency. A timescale of the 'fixation' by the sediment is determined, being of the order of days for (226)Ra and of the order of months for (40)K, so the progressive 'fixation' of (40)K by the clay minerals of the sediments is slower than in the case of (226)Ra.

New biomorphic SiC ceramics coated with bioactive glass for biomedical applications.

A new generation of light, tough and high-strength material for medical implants for bone substitutions with a good biological response is presented. The innovative product that fulfills all these requirements is based on biomorphic silicon carbide ceramics coated with a bioactive glass layer. The combination of the excellent mechanical properties and low density of the biomorphic SiC ceramics, used as a base material for implants, with the osteoconducting properties of the bioactive glass materials opens new possibilities for the development of alternative dental and orthopedic implants with enhanced mechanical and biochemical properties that ensures optimum fixation to living tissue. Biomorphic SiC is fabricated by molten-Si infiltration of carbon templates obtained by controlled pyrolysis of wood. Through this process, the microstructure of the final SiC product mimics that of the starting wood, which has been perfected by natural evolution. The basic features of such microstructure are its porosity (ranging from 30% to 70%) and its anisotropy, which resembles the cellular microstructure and the mechanical characteristics of the bone. The SiC ceramics have been successfully coated with a uniform and adherent bioactive glass film by pulsed laser ablation using an excimer ArF laser. The excellent coverage of the SiC rough surface without film spallation or detachment is demonstrated. In order to assess the coating bioactivity, in vitro tests by soaking the samples in simulated body fluid have been carried out. After 72 h, the formation of a dense apatite layer has been observed even in interconnecting pores by SEM and energy dispersive X-ray spectroscopy analysis demonstrating the bioactive response of this product.