Utilidad de la razón plaqueta/linfocito en la detección de sepsis neonatal temprana

Introducción: la sepsis neonatal temprana (SNT) es una afección sistémica que conlleva a una elevada morbimortalidad neonatal; establecer parámetros para un diagnóstico más sencillo y rápido son necesarios para su tratamiento oportuno. Objetivo: Evaluar si la razón plaqueta/linfocito (RPL) es útil en la detección de sepsis neonatal temprana. Método: Estudio de pruebas diagnósticas en donde se revisaron 122 historias clínicas de recién nacidos a término (33 con SNT y 89 sin SNT) atendidos en el servicio de neonatología del Hospital Víctor Ramos Guardia – Huaraz, 2016-2018. Se calculó el punto de corte mediante el índice de Youden y la curva ROC para el cálculo de la sensibilidad, especificidad, valor predictivo positivo (VPP) y negativo (VPN) de la RPL en el diagnóstico de SNT. Resultados: El punto de corte óptimo de la RPL fue de 35, con área bajo la curva de 0.858 (IC95%: 0.777-0.939), sensibilidad de 73%, especificidad del 96%, VPN de 86% y VPN del 90%. Conclusión: la razón plaqueta/linfocito es útil en la detección de sepsis neonatal temprana.Introduction: early neonatal sepsis (ENS) is a systemic condition leading to neonatal morbidity and mortality, establishing parameters for a simpler and faster diagnosis are necessary for timely treatment. Objective: To assess whether the platelet/ lymphocyte ratio (PLR) is useful in detecting early neonatal sepsis. Method: Study of diagnostic tests where 122 medical records of term infants (33 with ENS and 89 without ENS) attended in the neonatology service at the Hospital Víctor Ramos Guardia - Huaraz, 2016-2018 were reviewed. The cut-off point was calculated using the Youden index and the COR curve to calculate the sensitivity, specificity, positive predictive value (PPV) and negative (NPV) of the RPL in the diagnosis of ENS. Results: The optimal cut-off point of the PRL was 35, with an area under the curve of 0.858 (95%CI: 0.777-0.939), 73% sensitivity, 96% specificity, 86% NPV and 90% NPV. Conclusion: the platelet/lymphocyte ratio is useful in the detection of early neonatal sepsis.Tesi

Electric Drive Based on an Open-End Winding Surface PM Synchronous Machine with a Floating Capacitor Bridge

A speed control scheme is presented for a 3-phase surface permanent magnet synchronous machine with an openend stator winding fed by a three-phase inverter and a floating bridge inverter. The latter is used to compensate for the reactive power of the main inverter and to maximize the active power received by the motor, without exceeding the available stator current and DC-link voltage. To reduce the switching losses, the DC-link voltage of the floating inverter bridge varies depending on the operating condition of the motor and the controllability requirements of the system. The experimental results show that a significant improvement in the speed range at constant power is achievable, proportionally to the DC-link voltage of the floating bridge inverter

Improving Protein Crystal Quality by the Without-Oil Microbatch Method: Crystallization and Preliminary X-ray Diffraction Analysis of Glutathione Synthetase from Pseudoalteromonas haloplanktis

Glutathione synthetases catalyze the ATP-dependent synthesis of glutathione from l-γ-glutamyl- l-cysteine and glycine. Although these enzymes have been sequenced and characterized from a variety of biological sources, their exact catalytic mechanism is not fully understood and nothing is known about their adaptation at extremophilic environments. Glutathione synthetase from the Antarctic eubacterium Pseudoalteromonas haloplanktis (PhGshB) has been expressed, purified and successfully crystallized. An overall improvement of the crystal quality has been obtained by adapting the crystal growth conditions found with vapor diffusion experiments to the without-oil microbatch method. The best crystals of PhGshB diffract to 2.34 Å resolution and belong to space group P212121, with unit-cell parameters a = 83.28 Å, b = 119.88 Å, c = 159.82 Å. Refinement of the model, obtained using phases derived from the structure of the same enzyme from Escherichia coli by molecular replacement, is in progress. The structural determination will provide the first structural characterization of a psychrophilic glutathione synthetase reported to date