Primary prevention for acute kidney injury in ambulatory patients

Acute kidney injury (AKI) is a heterogeneous group of conditions characterized by a sudden decrease in glomerular filtration rate (GFR), which usually induces the accumulation of nitrogenous-waste substances in the blood. It is expressed as an increase in serum creatinine levels (≥ 0.3 mg/dl within 48 hours or ≥1.5 times from baseline within the previous 7 days) or by a urine volume reduction of ˂0.5 ml/kg/h in 6 hours [1]. AKI is a relevant condition since it is usually associated with 1–7% and 30–50% of hospital and intensive care unit (ICU) admissions, respectively; showing a significant morbidity-mortality rate, and progression to chronic kidney disease (CKD) [1–7]. Even though many strategies have been proposed to achieve an early AKI diagnosis (e.g. novel biomarkers, informatics alarms), and an AKI effective treatment (e.g. renal protective drugs, biocompatible renal replacement therapies), both objectives remain unachieved; therefore, AKI prevention is currently the best ‘therapeutic’ strategy for this condition

Desarrollo de un sistema Web para la administración de cuestionarios

n el presenta trabajo, se reportan avances del desarrollo de un sistema Web enfocado a la administración de cuestionarios con diferentes formatos, es decir, que puedan contener preguntas cerradas, abiertas y/o de opción múltiple, que incluyan texto, imágenes y video; que soporte un número ilimitado de usuarios; que sea compatible con cualquier navegador y que además, pueda ser gratuito para proyectos enfocados a la investigación

Actuadores de nitinol aplicados en la mimetización del sistema de propulsión de peces con median paired fin

Este artículo presenta una propuesta original para diseñar actuadores empleando una aleación con memoria de forma shape memory alloy conocida corno nitinol. La aplicación se centra en el uso de estos actuadores en un robot que mimetiza a los organismos poseedores de aletas de locomoción tipo median paired fin

Single layer centrifugation (SLC) for bacterial removal with Porcicoll positively modifies chromatin structure in boar spermatozoa

The storage of boar semen samples at 17 degrees C for artificial insemination (AI) doses enables the proliferation of the bacteria, making antibiotics necessary. This can contribute to the development of antimicrobial resistance (AMR). This study tested bacterial presence and sperm chromatin structure after using a low-density colloid (Porcicoll) as an antibiotic alternative to eliminate bacteria. Ejaculates (8 boars, 3 ejac-ulates each) were split as control and low-density colloid centrifugation (single layer centrifugation, SLC, 20%, and 30% Porcicoll) into 500 ml tubes. Analyses were carried out at days 0, 3, and 7 (17 degrees C) for microbial presence and sperm chromatin structure analysis: %DFI (DNA fragmentation) and %HDS (chromatin immaturity), monobromobimane (mBBr; free thiols and disulfide bridges), and chromomycin A3 (CMA3; chromatin compaction). Besides comparing bacterial presence (7 species identified) and chromatin variables between treatments, the associations between these sets of variables were described by canonical correlation analysis (CCA). Results showed a significant decrease of some bacteria or a complete removal after SLC (especially for P30). SLC also caused a decrease of %HDS and an increase of disulfide bridges and low and medium mBBr populations, suggesting the removal of immature sperm (poor chromatin compaction). CCA showed an association pattern compatible with the degradation of sperm chromatin parameters with bacterial contamination, especially Enterobacteria, P. aeuriginosa, and K. variicola. In conclusion, bacterial contamination affects sperm chromatin beyond DNA fragmentation; SLC with low-density colloid not only removes bacteria from boar semen, but also chromatin structure is enhanced after selection.(c) 2023 Published by Elsevier Inc

Recovery of retinal oxygenation after MEMS implant activation

Purpose: Retinal ischemia due to diabetic retinopathy or retinal vascular occlusions is the leading cause of blindness worldwide. Although, the underlying pathophysiology from each condition is different, the common end results are: inner retinal hypoxia and ischemia. Changes associated with retinal hypoxia include the simultaneous activation of different pathways including inflammatory, aerobic and anaerobic metabolic response. Supplementing intravitreal oxygen has been demonstrated as a novel option in preliminary reports. Our implantable MEMS oxygenator drivesoxygen from the sub-conjunctival space to the proximity of the inner retina. The main objective of this study is to determine the efficacy of the oxygenation therapy in an ischemic animal model. Methods: Nine eyes from six pigmented rabbits were included, split evenly between either healthy, implant-treated or non-treated groups. Retinal vein occlusion (RVO) was created in all animals from treated and non-treated groups 3 days prior to surgical implantation and activation of the oxygenator. Continuous measurements of pO2 levels were performed next to the diffuser and retinal vessels using an oxygen probe controlled by a micromanipulator and monitored under indirect ophthalmoscopy. Eyes were then enucleated and the retina was peeled off and cryogenically preserved in liquid nitrogen for subsequent analysis of protein expression. Results: RVO was confirmed in all animals immediately after the procedure and remained occluded over the experiment. Oxygenator devices were successfully implanted without complications. In the treated group, oxygen levels increased progressively after a couple of minutes of activation and remained over 15 mmHg and 100 mmHg respectively (Figure 1A). For the non-treated group, pO₂ levels did not increase at the retina or nearby the device (below 5mmHg). Changes among protein expression and ratio (upregulation on NFkB and PDH; down-regulation of HIF1a, NFkB/IKKa ratio and P-PDH/PDH ratio) were observed in the treated group (Figure 1B-C). Conclusions: The MEMS oxygenator device can be safely implanted into the eye. This study supports the feasibility of intravitreal oxygen delivery for treatment of ischemic retinal diseases through inflammatory response modulation. Future experiments will evaluate long-term efficacy

Épocas de nacimiento basadas en un índice climático para el ajuste de modelos estadísticos para peso vivo de ganado bovino en México

Artículo de investigación científica publicado en revista indizada.El objetivo fue comparar los efectos de una metodología para la clasificación de épocas climáticas, que tradicionalmente son utilizadas para establecer épocas de nacimiento (EN) en estudios y experimentos estadísticos. Esta metodología se basa en un índice de aridez (IA) para clasificar las EN utilizando información meteorológica histórica. Se trabajó una base de datos con un pedigrí de 7,460 animales, se ajustaron dos modelos para peso al nacimiento y peso al destete en bovinos Charolais manejados en pastoreo extensivo. Los modelos incluyeron el efecto fijo de grupo contemporáneo (GC= subclase de hato, sexo, año y EN) y edad de la madre. Los mismos modelos se compararon utilizando una clasificación tradicional de estaciones del año para clasificar las EN. Al estimar los componentes de varianza y valores genéticos (DEP) con sus exactitudes, los modelos fueron diferentes de acuerdo a la prueba de razón de verosimilitudes (P<0.01). El número de GC se redujo en 25 % para la EN basada en el IA, con GC con mayor número de individuos. El principal efecto observado en los modelos analizados fue el cambio en la jerarquización de las DEP para ambas características. Este método de clasificación de épocas de nacimiento, puede ayudar a mejorar el ajuste de modelos estadísticos en los sistemas ganaderos manejados en pastoreo extensivo

Robots Modulares para Cirugía Mínimamente Invasiva

Este artículo se enfoca en las consideraciones que se deben tomar en cuenta sobre el diseño de robots modulares que permitan auxiliar al médico en intervenciones de CMI (Cirugía Mínimamente Invasiva). Se presenta el estado del arte de los sistemas robóticos modulares tanto re-configurables como auto re-configurables, así como los dispositivos y materiales quirúrgicos usados en cirugía de mínima invasión con el fin de tomarlos como referencia en las propuestas de diseño, considerando la normatividad para dispositivos médicos y con un enfoque de diseño para dispositivos de ablación durante laparoscopías abdominales

Simulation and experimental testbed for adaptive video streaming in ad hoc networks

[EN] This paper presents a performance evaluation of the scalable video streaming over mobile ad hoc networks. In particular, we focus on the rate-adaptive method for streaming scalable video (H.264/SVC). For effective adaptation a new cross-layer routing protocol is introduced. This protocol provides an efficient algorithm for available bandwidth estimation. With this information, the video source adjusts its bit rate during the video transmission according to the network state. We also propose a free simulation framework that supports evaluation studies for scalable video streaming. The simulation experiments performed in this study involve the transmission of SVC streams with Medium Grain Scalability (MGS) as well as temporal scalability over different network scenarios. The results reveal that the rate-adaptive strategy helps avoid or reduce the congestion in MANETs obtaining a better quality in the received videos. Additionally, an actual ad hoc network was implemented using embedded devices (Raspberry Pi) in order to assess the performance of the proposed adaptive transmission mechanism in a real environment. Additional experiments were carried out prior to the implementation with the aim of characterizing the wireless medium and packet loss profile. Finally, the proposed approach shows an important reduction in energy consumption, as the study revealed.This paper was performed with the support of the National Secretary of Higher Education, Science, Technology and Innovation (SENESCYT)–Ecuador Government (scholarship 195-2012) and the Multimedia Communications Group (COMM) belong to the Institute of Telecommunications and Multimedia Applications (iTEAM)-Universitat Politècnica de València.Gonzalez-Martinez, SR.; Castellanos Hernández, WE.; Guzmán Castillo, PF.; Arce Vila, P.; Guerri Cebollada, JC. (2016). Simulation and experimental testbed for adaptive video streaming in ad hoc networks. Ad Hoc Networks. 52:89-105. https://doi.org/10.1016/j.adhoc.2016.07.007S891055

Información climática asociada a estaciones productivas para el ajuste de modelos estadísticos de sistemas bovinos bajo condiciones extensivas

Artículo de investigación publicado en revista internacional indizada.El objeto de este estudio fue desarrollar una metodología para clasificar épocas de nacimiento (EN) y evaluar su impacto en indicadores productivos al compararlas con un método tradicional de clasificación. Con información meteorológica, se generó un índice de aridez para clasificar las EN. Las EN propuesta y tradicional se compararon, incluyéndolas como grupo contemporáneo (GC= hato, sexo, año y EN) a modelos de evaluación genética de caracteres de peso vivo. Fueron estimados los componentes de varianza y valores genéticos (DEP) con sus exactitudes. La clasifica- ción propuesta explicó mayor variabilidad que la clasificación tradicional (≥9,8%). Los parámetros genéticos mostraron cambios importantes, siendo los más evidentes en peso al destete. Los modelos fueron diferentes de acuerdo a la prueba de razón de verosimilitudes (P<0,01). Se observó una mejora de estructura en los GC. Para los dos caracteres evaluados las correlaciones entre los valores genéticos de los animales fueron diferentes, lo que indica cambio en la jerarquización. Este método de clasificación de EN puede ayudar a mejorar el ajuste de modelos estadísticos en condiciones en las que exista la información climática necesaria para su implementación.Los autores agradecen al Consejo Nacional de Cien- cia y Tecnología por el financiamiento del proyecto CB168207 y al Instituto Politécnico Nacional a través del proyecto SIP20150746

Preparation and evaluation of PEG-coated zein nanoparticles for oral drug delivery purposes

The aim was to produce PEG-coated nanoparticles (NP-PEG), with mucus-permeating properties, for oral drug delivery purposes by using simple procedures and regulatory-approved compounds in order to facilitate a po- tential clinical development. For this purpose, zein nanoparticles were prepared by desolvation and, then, coated by incubation with PEG 35,000. The resulting nanocarriers displayed a mean size of about 200 nm and a negative zeta potential. The presence of PEG on the surface of nanoparticles was evidenced by electron microscopy and confirmed by FTIR analysis. Likely, the hydrophobic surface of zein nanoparticles (NP) was significantly reduce by their coating with PEG. This increase of the hydrophilicity of PEG-coated nanoparticles was associated with an important increase of their mobility in pig intestinal mucus. In laboratory animals, NP-PEG (fluorescently labelled with Lumogen® Red 305) displayed a different behavior when compared with bare nanoparticles. After oral administration, NP appeared to be trapped in the mucus mesh, whereas NP-PEG were capable of crossing the protective mucus layer and reach the epithelium. Finally, PEG-coated zein nanoparticles, prepared by a simple and reproducible method without employing reactive reagents, may be adequate carriers for promoting the oral bioavailability of biomacromolecules and other biologically active compounds with low permeability propertie