R E S U M E N Introducción: La anestesia raquídea consiste en la aplicación de una dosis de anestésico local en el espacio intratecal de la columna lumbar, por medio de agujas espinales cuyas características varían tanto en calibre como en diseño. Al terminar la aplicación de una anestesia raquídea se puede comprobar un volumen remanente de líquido en el interior de la aguja espinal. Objetivo: Medir y comparar el volumen remanente de líquido posterior a la aplicación de anestesia raquídea en 3 marcas comerciales de agujas espinales de calibre 27. Métodos: Este es un estudio observacional analítico de corte transversal; se escogieron 3 tipos comerciales de agujas de calibre 27: BD Whitacre punta de lápiz, Spinocan Quincke punta cortante y Disposable spinal needle. Tras la aplicación de una anestesia raquídea, el mismo operador, sin desconectar la jeringa de la aguja, depositó el volumen residual en un tubo de recolección, para que un segundo operador cuantificara el volumen con una micropipeta de precisión. Resultados: El volumen residual obtenido de las agujas espinales 27G mostró una diferencia estadísticamente significativa a favor de las agujas BD Whitacre (p<0,01), comparadas con las agujas Spinocan Quincke y Disposable spinal needle. Conclusiones: Se comprobó que las agujas BD Whitacre pencil point alojan un menor volumen residual después de una anestesia espinal. No se puede afirmar que este hallazgo tenga implicaciones clínicas. Son necesarios nuevos estudios para corroborar estos resultados.

ABSTRACT Introduction: Spinal anesthesia involves the administration of a dose of local anesthesia into the intrathecal space of the lumbar spine, using spinal needles with varying characteristics and design. When completing the administration of spinal anesthesia, you may check the volume of fluid remaining inside the spinal needle. Objective: To measure and compare the volume of residual fluid following the administration of spinal anesthesia using three different brands of 27 gauge spinal needles. Methods: This is an observational analytical cross-section trial for which tree types of 27 gauge commercial needles were selected: BD Whitacre pencil point, Spinocan Quincke sharp point, and Disposable spinal needle. Following the administration of spinal anesthesia, the same operator, without detaching the syringe from the needle, deposited the residual vol ume into a collection tube so that a second operator quantifies the volume using a precision micropipette. Results: The residual volume obtained fromthe27Gspinalneedlesshowed astatistically significant difference in favor of the BD Whitacre needles (P < 0.01), compared against Spinocan Quincke and Disposable spinal needle. Conclusions: The BD Whitacre pencil point proved to lodge less residual volume following spinal anesthesia. No clinical implications can be made from this finding and new studies are required to ratify these results.

El diagnóstico de la infección cervical ocasionada por el virus del papiloma humano (VPH), se realiza básicamente a través de la biopsia y/o de métodos moleculares como la reacción en cadena de la polimerasa (PCR). Los resultados de estos estudios en ocasiones no coinciden. En este estudio se evalúa la posible influencia de diferentes factores asociados a resultados falsos positivos y a falsos negativos de ambas pruebas. Se analizaron 271 muestras de cuello uterino de pacientes que acudieron a la consulta ginecológica durante el período 1999-2009, a las cuales se les tomó biopsia por presentar hallazgos colposcópicos y/o citológicos sospechosos de infección por VPH. Tomando en consideración al resultado de PCR como prueba estándar de oro, la biopsia presentó 14% de falsos positivos y 16,6% de falsos negativos, el diagnóstico de VPH en biopsia y PCR presentó mayor concordancia cuando las muestras abarcan la zona de transformación endo-exocervical, así como la presencia de metaplasia escamosa en la muestra y el tamaño del fragmento mayor (>0,5 cm); mientras que el tiempo de fijación, el tipo e intensidad de la inflamación, la hemorragia y la erosión del epitelio no fueron significativos. En conclusión, a fin de disminuir la discrepancia de los resultados entre la biopsia y prueba de ADN, sería importante que la muestra de biopsia incluya la zona de transformación del cuello uterino y al menos un fragmento mayor de 0,5 cm.

The diagnosis of cervical infection caused by human papilloma virus (HPV) is made basically through the biopsy and/or molecular methods such as polymerase chain reaction (PCR). The results of these studies sometimes do not match. In this work is evaluated the possible influence of different factors associated with results false positive and false negative of both tests. Were analyzed 271 samples from uterin cervix of patients presenting to the gynecologist during the period 1999-2009, to which were taken biopsies due present findings colposcopics and/or cytological suspicious of HPV infection. Considering the result of PCR as gold standard test, biopsy showed 14% false positive and false negative 16.6%, the diagnostic of VPH in biopsy and PCR showed greater concordance when samples include endo-exocervical transformation zone, and the presence of squamous metaplasia in the sample and size of the largest fragment (>0.5 cm); while the fixation time, the type and intensity of inflammation, bleeding and erosion of the epithelium were not significant. In conclusion, in order to reduce the discrepancy between the results of the biopsy and test DNA, it is important that the biopsy sample includes the transformation zone of the uterin cervix and at least one fragment greater than 0.5 cm.

The resistance/susceptibility of selected cattle breeds to brucellosis was evaluated in an F1 population generated by crossing animals classified as resistant (R) and susceptible (S) (R x R, R x S, S x R, S x S) based on challenges in vitro and in vivo. The association between single nucleotide polymorphisms identified in the coding region of the Slc11a1 gene and resistance/susceptibility was estimated. The trait resistance or susceptibility to brucellosis, evaluated by a challenge in vitro, showed a high heritable component in terms of additive genetic variance (h² = 0.54 ± 0.11). In addition, there was a significant association (p < 0.05) between the control of bacterial survival and two polymorphisms (a 3'UTR and SNP4 located in exon 10). The antibody response of animals classified as resistant to infection by Brucella abortus differed significantly (p < 0.05) from that of susceptible animals. However, there was no significant association between single nucleotide polymorphisms located in the Slc11a1 gene and the antibody response stimulated by a challenge in vivo.