Efecto de la luz en la germinación de semillas de Pterocarpus rohrii Vahl

Pterocarpus rohrii Vahl, conocida comúnmente como ¨charapa caspi¨ en Perú. Es un árbol de 15 a 35 m de altura que crece en bosques secos cuya madera es empleada en carpintería. Constituyendo ser una especie de importancia para los programas de reforestación. Ante el potencial maderero de esta especie es que se tomó como objetivo del presente trabajo, determinar el efecto de la de la luz en la germinación de semillas de Pterocarpus rohrii Vahl. El material biológico (frutos) procedió del Jardín Botánico de la Universidad Nacional de Trujillo. Mientras que la fase experimental se desarrolló en el Laboratorio del Instituto de papa y Cultivos Andinos. Donde se extrajo las semillas, distribuyéndose 10 grupos de 30 semillas c/u. Las cuales fueron colocadas en placas de Petri, de las cuales 5 placas fueron cubiertas con papel de aluminio. Para que finalmente tanto las placas cubiertas, como las descubiertas fueron colocadas en incubación. El diseño estadístico fue en completamente al azar. Encontrándose la no existencia de diferencias estadísticas significativa entre las variables evaluadas. Se concluye que la luz no influye en la germinación de semillas de Pterocarpus rohrii Vahl

Temporal multiplexing with adaptive optics for simultaneous vision.

We present and test a methodology for generating simultaneous vision with a deformable mirror that changed shape at 50 Hz between two vergences: 0 D (far vision) and -2.5 D (near vision). Different bifocal designs, including toric and combinations of spherical aberration, were simulated and assessed objectively. We found that typical corneal aberrations of a 60-year-old subject changes the shape of objective through-focus curves of a perfect bifocal lens. This methodology can be used to investigate subjective visual performance for different multifocal contact or intraocular lens designs

Evolution of EEG motor rhythms after spinal cord injury: A longitudinal study

Spinal cord injury (SCI) does not only produce a lack of sensory and motor function caudal to the level of injury, but it also leads to a progressive brain reorganization. Chronic SCI patients attempting to move their affected limbs present a significant reduction of brain activation in the motor cortex, which has been linked to the deafferentation. The aim of this work is to study the evolution of the motor-related brain activity during the first months after SCI. Eighteen subacute SCI patients were recruited to participate in bi-weekly experimental sessions during at least two months. Their EEG was recorded to analyze the temporal evolution of the event-related desynchronization (ERD) over the motor cortex, both during motor attempt and motor imagery of their paralyzed hands. The results show that the a and ß ERD evolution after SCI is negatively correlated with the clinical progression of the patients during the first months after the injury. This work provides the first longitudinal study of the event-related desynchronization during the subacute phase of spinal cord injury. Furthermore, our findings reveal a strong association between the ERD changes and the clinical evolution of the patients. These results help to better understand the brain transformation after SCI, which is important to characterize the neuroplasticity mechanisms involved after this lesion and may lead to new strategies for rehabilitation and motor restoration of these patients

Caracterización de frutos, semillas y fibras de Gossypium barbadense “algodón Pardo”

La industria textil emplea ¨tintes artificiales¨ en las fibras de algodón, los cuales han resultado perjudiciales para la salud. El empleo de estos tintes puede ser reemplazado por el uso de variedades que producen fibras de colores, los algodones nativos del Perú, que poseen diferentes colores y tonalidades. Ante la necesidad de conocimiento en esta área se planteó como objetivo determinar la caracterización de los frutos, semillas y fibras de Gossypium barbadense “algodón pardo”. Las semillas procedieron de San Benito-Cajamarca, la fase experimental se realizó en el Laboratorio de Biotecnología del Instituto de la Papa y Cultivos Andinos de la Universidad Nacional de Trujillo con 30 repeticiones. En el fruto se encontró una longitud de 4,26 cm y un ancho de 4,11 cm. Además de presentar 3,5 lóculos por fruto. En la semilla, se presenció 0,78 cm de largo y 0,49 cm de ancho, así como un peso de 2,11 g. Por otro lado, en la fibra un 13,06 mm de largo, 24,25 μm de ancho y un peso de 1,52 g de fibra por cápsula. Se concluye que G. barbadense, presenta características de fruto, semilla y fibra propias de una especie nativa de algodón de fibra de color

Meropenem heteroresistance in clinical isolates of OXA-48–producing Klebsiella pneumoniae

OXA-48–producing Klebsiella pneumoniae isolates often show growth of colonies within inhibition zones in carbapenem diffusion assays. The nature of these colonies was investigated in a series of clinical isolates of OXA-48–producing K. pneumoniae obtained in the context of a hospital outbreak, and they were found to be persistent colonies that reproduced again the same phenotype when they were collected and tested in diffusion assays again. The frequency of mutations conferring resistance to meropenem (8 µg/mL) was determined for the same isolates. The average mutation frequency was 5.47·10-6 (range: 2.59·10-8–5.87·10-5), and the analysis of several resistant mutants showed that all of them had mutations in the ompK36 porin gene. Heteroresistance was investigated using population analysis profiling. The profiles were compatible with mutation frequency assays, and all the colonies analyzed were resistant mutants. In OXA-48–producing K. pneumoniae, the growth of persisters seems to be specific of diffusion assays

Morfometría de fruto y semilla de Bixa orellana L. “achiote”

Bixa orellana L. “achiote” es una planta de interés por poseer numerosas propiedades medicinales, nutricionales y económicas. Ante la necesidad de un mayor conocimiento se propuso como objetivo de investigación determinar la morfometría de fruto y semilla de Bixa orellana L. “achiote”. El material vegetal (frutos) procedieron de Laredo - Trujillo, mientras que la fase experimental se realizó en el Laboratorio de Biotecnología del Instituto de la Papa y Cultivos Andinos de la Universidad Nacional de Trujillo, el experimento estuvo constituido por 30 unidades muestrales.  Los resultados referentes al fruto, se encontró que tienen 4,6 ± 0,37 cm de largo, 3,3 ± 0,35 cm de ancho, mientras que el peso del fruto con semilla es de 3,3 ± 0,46 g y el número de semillas por fruto es de 35 ± 6,59. Las semillas tienen una longitud de 0,5 ± 0,02 cm y un ancho de 0,4 ± 0,02 cm. Por otro lado, el peso promedio de cada semilla fue de 0,044 ± 0,01 g, siendo el peso total de semillas contenidas en el fruto de 1,55 ± 0,29 g.  Se concluye que B. orellana L. exhibe una morfometría de frutos y semillas típico de la variedad de flores rosadas

Review of concepts in therapeutic decision-making in HER2-negative luminal metastatic breast cancer

Purpose: Hormone receptor (HR)-positive, Human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC) requires a therapeutic approach that takes into account multiple factors, with treatment being based on anti-estrogen hormone therapy (HT). As consensus documents are valuable tools that assist in the decision-making process for establishing clinical strategies and optimize the delivery of health services, this consensus document has been created with the aim of developing recommendations on cretiera for hormone sensitivity and resistance in HER2-negative luminal MBC and facilitating clinical decision-making. Methods: This consensus document was generated using a modification of the RAND/UCLA methodology, which included the definition of the project and identification of issues of interest, a non-exhaustive systematic review of the literature, an analysis and synthesis of the scientific evidence, preparation of recommendations, and external evaluation with a panel of 64 medical oncologists specializing in breast cancer. Results: A Spanish panel of experts reached consensus on 32 of the 32 recommendations/conclusions presented in the first round and were accepted with an approval rate of 100% about definition of metastatic disease not susceptible to local curative treatment, definition of hormone sensitivity and hormone resistance in metastatic luminal disease and therapeutic decision-making. Conclusion: We have developed a consensus document with recommendations on the treatment of patients with HER2-negative luminal MBC that will help to improve therapeutic benefits

Sex-Specific Effects of High Yolk Androgen Levels on Constitutive and Cell-Mediated Immune Responses in Nestlings of an Altricial Passerine

Avian embryos are exposed to yolk androgens that are incorporated into the egg by the ovulating female. These steroids can affect several aspects of embryo development, often resulting in increases in overall size or the speed of growth of different traits. However, several studies suggest that they also entail immune costs to the offspring. In this study, we explored whether variation in yolk androgen concentration affected several measures of the constitutive and cell-mediated immune axes in the spotless starling (Sturnus unicolor). Using a within-brood design, we injected different doses of androgens (testosterone and androstenedione) into the eggs. Our study showed that experimentally increased yolk androgens led to sex-specific immunosuppression in both the innate and adaptive axes of the immune system. Both cell-mediated immune response (CMI) and lysozyme activity decreased with increasing androgen levels injected into the egg in the case of male nestlings, whereas there were no effects on females. The effects that we found were always linear: no quadratic or threshold patterns were detected. We found no effects of the experimental treatment in hemolysis or agglutination capacity, but these measures were negatively correlated with CMI, suggesting negative correlation among different branches of the immune system. Blood (trypanosomes and hemosporidians) and intestinal (coccidia) parasites were not affected by the experimental increase of yolk androgen levels. Our results show that in our study species yolk androgens induce immunosuppression in some axes of the male nestling immune system. Further studies should analyze the proximate causes for these contrasting effects in different axes of the immune system and the reason for the differential impact on males and females

Determinación de la fuerza de roce con el aire usando nuevas tecnologías

En este trabajo presentamos un experimento de bajo costo para estudiar la caída de los cuerpos cuando los efectos del roce con el aire son significativos. Este experimento permite determinar la cinemática de un cuerpo que cae en el aire y “descubrir” las leyes que rigen el roce de un objeto en un medio fluido y su dependencia con la velocidad del mismo. El dispositivo experimental hace uso de una cámara digital comercial en modo vídeo. Se analiza la caída de filtros de café y globos cargados con diferentes pesos. Nuestro estudio revela que en su caída, estos objetos alcanzan rápidamente una velocidad constante que es proporcional al peso de los mismos. Usando las leyes de Newton podemos inferir que esta fuerza de roce es proporcional al cuadrado de la velocidad