Corticospinal vs Rubrospinal Revisited: An Evolutionary Perspective for Sensorimotor Integration.

The knowledge about how different subsystems participate and interplay in sensorimotor control is fundamental to understand motor deficits associated with CNS injury and movement recovery. The role of corticospinal (CS) and rubrospinal (RS) projections in motor control has been extensively studied and compared, and it is clear that both systems are important for skilled movement. However, during phylogeny, the emerging cerebral cortex took a higher hierarchical role controlling rubro-cerebellar circuits. Here, we present anatomical, neurophysiological, and behavioral evidence suggesting that both systems modulate complex segmental neuronal networks in a parallel way, which is important for sensorimotor integration at spinal cord level. We also highlight that, although specializations exist, both systems could be complementary and potentially subserve motor recovery associated with CNS damage.

Choice of cystometric technique impacts detrusor contractile dynamics in wistar rats.

The objective of the current animal study was to investigate factors contributing to the different phases of the cystometrogram (CMG) in order to address disparities in research data reported in the current literature. Three experiments in 20 female Wistar rats were designed to investigate (1) the effects of anesthesia on the contractile pattern of the bladder during micturition; (2) the impact of the physical characteristics of the CMG technique upon the accuracy of intra-vesical pressure recordings; and (3) identification of physiological and methodological factors associated with the emptying and rebound phases during CMG. Variables tested included awake versus urethane-anesthetized conditions, use of a single catheter for both filling and intra-vesical pressure (Pves) recording versus a separate two catheter approach, and comparisons between ureter, bladder dome, and urethral catheter placements. Both awake and anesthetized conditions contributed to variations in the shape and magnitude of the CMG pressure curves. In addition, catheter size, acute incision of the bladder dome for catheter placement, use of the same catheter for filling and Pves recordings, as well as the placement and positioning of the tubing, all contributed to alterations of the physiological properties and characteristic of the various CMG phases, including the frequent occurrence of an artificial rebound during the third phase of micturition. The present results demonstrate how different experimental conditions lead not only to variability in Pves curves, but consistency of the measurements as well, which needs to be accounted for when interpreting CMG outcome data.

Leuprolide Acetate, a GnRH Agonist, Improves the Neurogenic Bowel in Ovariectomized Rats with Spinal Cord Injury.

BACKGROUND: Electromyographic studies have shown that external anal sphincter activity is modified in response to distension in animals with spinal cord injury. Gonadotropin-releasing hormone and its agonist leuprolide acetate have neurotrophic properties in animals with spinal cord injury. AIM: This study was to determine the effects of leuprolide acetate treatment on electromyographic activity of the external anal sphincter and anorectal manometry in ovariectomized rats with spinal cord injury. METHODS: Adult ovariectomized rats were divided in three groups: (a) sham of spinal cord injury, (b) spinal cord injury treated with saline solution, and (c) spinal cord injury treated with leuprolide acetate. The spinal cord injury was induced by clamping at level T9. Leuprolide acetate dosage of 10 µg/kg was proctored intramuscular for 5 weeks, commencing the day after the lesion. Electromyography of the external anal sphincter, anorectal manometry, and volume of the cecum were evaluated in all groups. RESULTS: The electromyographic study of the external anal sphincter activity showed a significant improvement in injured rats treated with leuprolide acetate. Manometric analysis and cecum volume data obtained in animals with leuprolide acetate were very similar to those found in the sham group. CONCLUSIONS: These results demonstrate that leuprolide acetate treatment improves the neurogenic colon in ovariectomized rats with spinal cord injury.

Quantitative methods for assessing local and bodywide contributions to Wolbachia titer in maternal germline cells of Drosophila.

BACKGROUND: Little is known about how bacterial endosymbionts colonize host tissues. Because many insect endosymbionts are maternally transmitted, egg colonization is critical for endosymbiont success. Wolbachia bacteria, carried by approximately half of all insect species, provide an excellent model for characterizing endosymbiont infection dynamics. To date, technical limitations have precluded stepwise analysis of germline colonization by Wolbachia. It is not clear to what extent titer-altering effects are primarily mediated by growth rates of Wolbachia within cell lineages or migration of Wolbachia between cells. RESULTS: The objective of this work is to inform mechanisms of germline colonization through use of optimized methodology. The approaches are framed in terms of nutritional impacts on Wolbachia. Yeast-rich diets in particular have been shown to suppress Wolbachia titer in the Drosophila melanogaster germline. To determine the extent of Wolbachia sensitivity to diet, we optimized 3-dimensional, multi-stage quantification of Wolbachia titer in maternal germline cells. Technical and statistical validation confirmed the identity of Wolbachia in vivo, the reproducibility of Wolbachia quantification and the statistical power to detect these effects. The data from adult feeding experiments demonstrated that germline Wolbachia titer is distinctly sensitive to yeast-rich host diets in late oogenesis. To investigate the physiological basis for these nutritional impacts, we optimized methodology for absolute Wolbachia quantification by real-time qPCR. We found that yeast-rich diets exerted no significant effect on bodywide Wolbachia titer, although ovarian titers were significantly reduced. This suggests that host diets affects Wolbachia distribution between the soma and late stage germline cells. Notably, relative qPCR methods distorted apparent wsp abundance, due to altered host DNA copy number in yeast-rich conditions. This highlights the importance of absolute quantification data for testing mechanistic hypotheses. CONCLUSIONS: We demonstrate that absolute quantification of Wolbachia, using well-controlled cytological and qPCR-based methods, creates new opportunities to determine how bacterial abundance within the germline relates to bacterial distribution within the body. This methodology can be applied to further test germline infection dynamics in response to chemical treatments, genetic conditions, new host/endosymbiont combinations, or potentially adapted to analyze other cell and tissue types.

Dietary saccharides and sweet tastants have differential effects on colonization of Drosophila oocytes by Wolbachia endosymbionts.

Wolbachia bacteria are widespread, maternally transmitted endosymbionts of insects. Maintenance of sufficient Wolbachia titer in maternal germline cells is required for transmission efficacy. The mechanisms that regulate Wolbachia titer are not well understood; however, dietary sucrose was reported to elevate oocyte Wolbachia titer in Drosophila melanogaster whereas dietary yeast decreased oocyte titer. To further investigate how oocyte Wolbachia titer is controlled, this study analyzed the response of wMel Wolbachia to diets enriched in an array of natural sugars and other sweet tastants. Confocal imaging of D. melanogaster oocytes showed that food enriched in dietary galactose, lactose, maltose and trehalose elevated Wolbachia titer. However, oocyte Wolbachia titers were unaffected by exposure to the sweet tastants lactulose, erythritol, xylitol, aspartame and saccharin as compared to the control. Oocyte size was generally non-responsive to the nutrient-altered diets. Ovary size, however, was consistently smaller in response to all sugar- and sweetener-enriched diets. Furthermore, most dietary sugars administered in tandem with dietary yeast conferred complete rescue of oocyte titer suppression by yeast. All diets dually enriched in yeast and sugar also rescued yeast-associated ovary volume changes. This indicates oocyte colonization by Wolbachia to be a nutritionally sensitive process regulated by multiple mechanistic inputs.

El Suicidio (desded el punto de vista médico legal)

1.El suicidio puede producirse sin que un sujeto padesca de enajenacion mental por sonsiguiente en la lucidez de los sentidos,2-Es mas frecuente en los enajenados,3-En un individuo conciente de sus actos y no enajenada es manifestacion suprema de la libertad y de una firme voluntad,4-Segun las estadisiticas de diferentes paises el suicidio va creciendo de numero conforme avanza la civilización,5-Son inumerables las formas de muerte voluntaria siendo el suicidio una de ellas,6-El suicidio en nuestros tiempos no es punible por la legislación de paises civilizados,7-Es inmoral y debe evitarse por todos los medios,8-La complicidad del suicidio ya sea activa o pasiva es castigada por las leyes,9-Desde el punto de vista médicolegal es esencial el diagnostico entre suicidio homicidio y accidente,10-Las causas del suicidio pueden ser predisponentes y determinantes