Genetic Differentiation and Origin of Naturalized Rainbow Trout Populations From Southern Chile, Revealed by the mtDNA Control Region Marker.

Numerous self-sustaining naturalized or introduced populations of rainbow trout (Oncorhynchus mykiss) are widely distributed throughout the freshwaters of southern Chile. In this study, analysis of the mitochondrial DNA control region (CR) marker was conducted to investigate the level of genetic divergence among populations and their phylogenetic relationships with respect to native lineages. This information provided a framework to interpret the genetic structure and origin that was shaped during historical trout introduction efforts. To this end, we analyzed eleven naturalized populations of lakes and rivers from five basins. The CR marker revealed five haplotypes. The overall haplotype (H) and nucleotide (Π) diversities were 0.684 ± 0.030 and 0.00460 ± 0.00012, respectively. Global F ST was 0.169, with several pairwise F ST estimates showing significant differences (P < 0.05). The exact test of population differentiation corroborated this result (P < 0.001). Significant geographic structure was found (P < 0.05), with variations explained primarily by differences within populations (61.65%) and among group basins (20.82%). Maximum likelihood phylogenetic analysis resolved two distinct clades with medium bootstrap support when naturalized populations were aligned in conjunction with reference native lineages. The haplotype network revealed a close association between naturalized populations and four main haplotypes representative of three native ecotypes or lineages from western North America (rainbow trout, steelhead trout and redband trout). These results indicate a genetic population structuring for naturalized rainbow trout from southern Chile and an origin probably represented by multiple lineages sources. Thus, mitochondrial DNA data strongly suggest that stocking of rainbow trout from different origins may have occurred during or after the initial introduction efforts.

Switching Stable Kidney Transplant Recipients to a Generic Tacrolimus Is Feasible and Safe, but It Must Be Monitored.

Background. Tacrolimus is the primary immunosuppressive drug used in kidney transplant patients. Replacing brand name products with generics is a controversial issue that we studied after a Chilean Ministry of Health mandate to implement such a switch. Methods. Forty-one stable Prograf (Astellas) receiving kidney transplant patients were switched to a generic tacrolimus (Sandoz) in a 1 : 1 dose ratio and were followed up for up to 8 months. All other drugs were maintained as per normal practice. Results. Neither tacrolimus doses nor their trough blood levels changed significantly after the switch, but serum creatinine did: 1.62 ± 0.90 versus 1.75 ± 0.92 mg/dL (p < 0.001). At the same time, five graft biopsies were performed, and two of them showed cellular acute rejection. There were nine infectious episodes treated satisfactorily with proper therapies. No patient or graft was lost during the follow-up time period. Conclusion. Switching from brand name tacrolimus to a generic tacrolimus (Sandoz) is feasible and appears to be safe, but it must be monitored carefully by treating physicians.

Sonic versus ultrasonic activation for the cleaning of the root canal after post space preparation: an in vitro study / Activación sónica versus ultrasónica en la limpieza del canal radicular posterior a la preparación del lecho para poste: estudio in vitro

To compare the efficacy of 3 intracanal cleaning protocols used before cementation of prosthetic posts. Material and Methods: 40 anterior teeth received endodontic treatment in hand, using lateral condensation technique. After two weeks, gutta-percha was appropriately removed from the teeth to get the necessary space to install a post. Then, teeth were randomly divided into groups; root surface was treated with chlorhexidine (CHX) activated by ultrasound (US) (group I), with chlorhexidine activated by sonic instrumentation (S) (group II), chlorhexidine without activation (group III) and without treatment (group IV). All teeth were fractured longitudinally getting 2 sections. The middle third of the root canal was microphotographed with a scanning electron microscope (SEM) and the contaminated surface was measured using detritus with ImageJ 1.47. It was analyzed with Kruskal-Wallis-test using GraphPad Prism 5.01. Results: The median percentage of contaminated area of Group I was 20.06 percent, Group II, 19.3 percent; Group III, 36.05 percent; and Group IV, 56.45 percent. Conclusion: There are significant differences among different intracanal cleaning protocols in the removal efficiency of detritus from the root canal, being the activated protocols the most effective ones...

Comparar la eficacia de 3 protocolos de limpieza intraconducto utilizados previo a la cementación de pernos protésicos. Materiales y métodos: A 40 dientes anteriores se les realizó un tratamiento endodóntico en mano, mediante la técnica de condensación lateral. Luego de dos semanas, se realizó la desobturación de los mismos retirando la cantidad de gutapercha que otorgue el espacio necesario para alojar un poste. A continuación, los dientes fueron divididos aleatoriamente en grupos; superficie radicular tratada con clorhexidina (CHX) activado con ultrasonido (US) (grupo I), con clorhexidina activado con instrumental sónico (S) (grupo II), con clorhexidina sin activación (grupo III) y sin ningún tratamiento (grupo IV). Todos los dientes se fracturaron longitudinalmente obteniendo 2 secciones. Se microfotografió el tercio medio del conducto radicular con microscopio electrónico de barrido (MEB) y se midió la superficie contaminada con detritus usando ImageJ 1.47. Se analizó con test Kruskall-Wallis usando GraphPad-Prism 5.01. Resultados: La mediana del porcentaje de área contaminada del Grupo I fue 20,06 por ciento, Grupo II de 19,3 por ciento, Grupo III de 36,05 por ciento y Grupo IV de 56,45 por ciento. Conclusión: Existen diferencias significativas entre los distintos protocolos de limpieza intraconducto en la eficacia de eliminación de detritus del conducto radicular, siendo los protocolos activados más eficientes...

Analisis de torsion y aplicacion a una escalera helicoidal

El trabajo ha sido efectuado con el proposito de exponer en forma clara y ordenada el analisis de torsión en diversas secciones, apoyado exclusivamente en la teoria de la elasticidad, con fin de poder tener cuadros resumen de las principales formulas de la torsion deducidas matematicamente. El contenido de este volumen se divide en capítulos que comprenden campos debidamente reconocidos de la teoria y el estudio. El primer capitulo abarca sobre torsion elemental donde se tiene ejemplos como aplicaciones. El capitulo dos es la base del proyecto en el aspecto analitico. Los capitulos tres y cuatro están dedicados a introducir al estudiante profesional un enfoque de la torsion para cualquier seccion, teniendo en cuenta la teoria de la elasticidad y teniendo en cuenta el alabeo de las secciones transversales lo cual estara definido por una funcion de tension. En la segunda parte del proyecto se tiene un cálculo analitico de una escalera helicoidal, la cuál se aplico como numero a una rampa helicoidal.

Analisis estructural

Contenido:1.Analisis estructural II 2. Calculo de las deformaciones 3.Metodo de la viga conjugada 4. Carga virtual en estructuras reticulares 5. Ecuacion completa de los trabajos virtuales 6. Solucion de reticulares hiperestaticos 7. Analisis estructural III 8. Metodo de las deformaciones 9. Prueba de cross.