Incidencia de las infecciones asociadas a cuidados de salud en el departamento de pediatría del hospital de niños dr. Jorge lizarraga de la ciudad hospitalaria dr. Enrique Tejera durante Abril – Julio del 2013.

TUTOR: Dr. Harold Guevara RivasLa prevención y manejo adecuado de las Infecciones Asociadas a cuidados de salud (IACS) constituyen un desafío para el equipo de salud. Objetivo: Establecer la incidencia de las IACS en el Departamento de pediatría del Hospital de niños Dr. Jorge Lizárraga de la Ciudad Hospitalaria Dr. Enrique Tejera, durante Abril–Julio del 2013. Materiales y Métodos: La investigación fue descriptiva, longitudinal, prospectiva y no experimental. La población estuvo representada por 1234 niños pacientes ingresados en el periodo y muestra de 133 casos detectados con un sistema de vigilancia activa de los pacientes con sospecha y corroboración de IACS con manifestaciones clínicas y de laboratorio. Resultados: Se estudiaron 133 casos de IACS, incidencia global de 10,8%. evaluando la incidencia por los diferentes servicios de hospitalización. De los pacientes con IACS 57,1% pertenecían al sexo masculino con predominio estadísticamente significativo, mayor porcentaje de IACS en menores de 1 año de edad. El principal motivo de hospitalización fueron las patologías del sistema respiratorio. Los factores de riego para IACS más frecuentes fueron catéter venoso central con un recambio del mismo, nutrición parenteral, sondaje vesical o nasogástrico. En 63,2% de los casos hubo algún aislamiento en los cultivos, con predominio de las bacterias como agentes etiológicos (78,2%), especialmente las Gram-negativas (76,4%). Conclusión: Los pacientes afectados fueron lactantes menores masculinos, la bacteriemia fue la forma más frecuente de IACS. El catéter venoso central y la nutrición parenteral fueron los factores de riesgo más frecuentemente implicados. Se recomienda implementar un sistema de vigilancia epidemiológica activa de IACS

Can Arsenates Replace Phosphates in Natural Biochemical Processes? A Computational Study

A bacterial strain, GFAJ-1 was recently proposed to be substituting arsenic for phosphorus to sustain its growth. We have performed theoretical calculations for analyzing this controversial hypothesis by examining the addition of phosphate to ribose and glucose. Dispersion corrected Density Functional Theory (DFT) calculations in small molecules and QM/MM calculations on clusters derived from crystal structure are performed on structures involved in phosphorylation, considering both phosphates and arsenates. The exothermicity as well as the activation barriers for phosphate and arsenate transfer were examined. Quantum mechanical studies reveal that the relative stability of the products decrease marginally with successive substitution of P with As. However, simultaneously, the transition state barriers decrease with P replacement. This indicates that, kinetically, addition of As is more facile. Pseudorotation barriers for the pentavalent intermediates formed during the nucleophilic attack are also analyzed. A monotonic increase in barriers is observed for pseudorotation with the successive replacement of phosphorus with arsenic in methyl-DHP. A glucokinase crystal structure was chosen to construct a model system for QM/MM calculations. Free energy of the reaction (Δ<i>G</i>) reduces by less than 2.0 kcal/mol and the activation barrier (Δ<i>G</i>^‡) decreases by ∼1 kcal/mol on arsenic incorporation. Thus, both DFT and QM/MM calculations show that arsenic can readily substitute phosphorus in key biomolecules. Secondary kinetic isotope effects for phosphorylation mechanism obtained by QM/MM calculations are also reported. The solvent kinetic isotopic effects (SKIE) for ATP and ATP (As) are calculated to be 5.81 and 4.73, respectively. A difference of ∼1.0 in SKIE suggests that it should be possible to experimentally determine the As–phosphorylation process

What Stabilizes the Li_<i>n</i>P_<i>n</i> Inorganic Double Helices?

Recently, inorganic double-helical structures based on simple lithium and phosphorus salts have been demonstrated. We have analyzed the nature of bonding in these double helices of Li_<i>n</i>P_<i>n</i> (<i>n</i> = 7–9). Similar to DNA, noncovalent interactions and cooperativity play an important role in stabilizing the inorganic double helices. Cooperativity imparts an additional stabilization of 4.5 to 10.1 kcal/mol per Li–P pair. In addition, the ionicity of Li–P units further augments the stability of these inorganic double-helix structures in contrast with the canonical base pairs in DNA, where noncovalent interactions determine the duplex stability. Unwinding is shown to be unfavorable, and cleavage of a few edge Li–P bonds leads to spontaneous self-healing into the intact double-helix tract

Jammed elastic shells-a 3D experimental soft frictionless granular system

We present a new experimental system of monodisperse, soft, frictionless, fluorescent labeled elastic shells for the characterization of structure, universal scaling laws and force networks in 3D jammed matter. The elastic shells in a jammed packing are deformed in such a way that at each contact one of the shells buckles with a dimple and the other remain spherical, closely resembling overlapping spheres. Using confocal microscopy, we obtained 3D stacks of images of shells at different volume fractions which were subsequently processed in ImageJ software to find their coordinates. The determination of 3D coordinates involved three steps: locating the edges of shells in all 2D slices, analyzing their shape and subsequently finding their 2D coordinates, and finally determining their 3D centers by grouping the corresponding 2D coordinates. From this analysis routine we obtained particle coordinates with sub-pixel accuracy. In a contact pair we also identified the shell that underwent buckling forming a dimple by analyzing the intensity profile of a line that connects the centers of particle pairs. The amorphous structure of the packing was analyzed as a function of distance to the jamming threshold by investigating the radial distribution function, bond order parameters, contact numbers and the number of dimples per particle (buckling number), which is a unique property of this system. We find that the power law scaling of the contact number with excess volume fraction deviated from theoretical and computer simulation predictions. In addition, the buckling number also showed a similar scaling as that of the contact number with distance to the jamming transition. This journal i

Improvements in Diet and Physical Activity–Related Psychosocial Factors Among African Americans Using a Mobile Health Lifestyle Intervention to Promote Cardiovascular Health: The FAITH! (Fostering African American Improvement in Total Health) App Pilot Study

BackgroundAfrican Americans continue to have suboptimal cardiovascular health (CVH) related to diet and physical activity (PA) behaviors compared with White people. Mobile health (mHealth) interventions are innovative platforms to improve diet and PA and have the potential to mitigate these disparities. However, these are understudied among African Americans. ObjectiveThis study aims to examine whether an mHealth lifestyle intervention is associated with improved diet and PA-related psychosocial factors in African Americans and whether these changes correlate with diet and PA behavioral change. MethodsThis study is a retrospective analysis evaluating changes in diet and PA-related self-regulation, social support, perceived barriers, and CVH behaviors (daily fruit and vegetable intake and moderate-intensity PA [MPA] per week) in 45 African American adults (mean age 48.7 years, SD 12.9 years; 33/45, 73% women) enrolled in the FAITH! (Fostering African American Improvement in Total Health) app pilot study. The intervention is a 10-week, behavioral theory–informed, community-based mHealth lifestyle intervention delivered through a mobile app platform. Participants engaged with 3 core FAITH! app features: multimedia education modules focused on CVH with self-assessments of CVH knowledge, self-monitoring of daily fruit and vegetable intake and PA, and a sharing board for social networking. Changes in self-reported diet and PA-related self-regulation, social support, perceived barriers, and CVH behaviors were assessed by electronic surveys collected at baseline and 28 weeks postintervention. Changes in diet and PA-related psychosocial factors from pre- to postintervention were assessed using paired 2-tailed t tests. The association of changes in diet and PA-related psychosocial variables with daily fruit and vegetable intake and MPA per week was assessed using Spearman correlation. Associations between baseline and 28-week postintervention changes in diet and PA-related psychosocial measures and CVH behaviors with covariates were assessed by multivariable linear regression. ResultsParticipants reported improvements in 2 subscales of diet self-regulation (decrease fat and calorie intake, P=.01 and nutrition tracking, P<.001), one subscale of social support for healthy diet (friend discouragement, P=.001), perceived barriers to healthy diet (P<.001), and daily fruit and vegetable intake (P<.001). Improvements in diet self-regulation (increase fruit, vegetable, and grain intake, and nutrition tracking) and social support for healthy diet (friend encouragement) had moderate positive correlations with daily fruit and vegetable intake (r=0.46, r=0.34, and r=0.43, respectively). A moderate negative correlation was observed between perceived barriers to healthy diet and daily fruit and vegetable intake (r=−0.25). Participants reported increases in PA self-regulation (P<.001). Increase in social support subscales for PA (family and friend participation) had a moderate positive correlation with MPA per week (r=0.51 and r=0.61, respectively). ConclusionsOur findings highlight key diet and PA-related psychosocial factors to target in future mHealth lifestyle interventions aimed at promoting CVH in African Americans