Successful Xenografts of Second Trimester Human Fetal Brain and Retinal Tissue in the Anterior Chamber of the Eye of Adult Immunosuppressed Rats

Successful xenografting of first trimester human fetal CNS tissue and retina has been reported in the literature. We wished to test the feasibility ofusing the anterior chamber ofthe rat eye to support the development of more mature human fetal xenografts. Here we report on the successful outcome of human brain and retinal transplants. Adult host rats immunosuppressed with cyclosporin A accepted these xenografts and supported their further development. Periodic examination of the host eyes using a direct ophthalmoscope or an ophthalmic slit lamp permitted direct visual monitoring of the health and growth of the transplants. Histologically it was possible to identify neuronal, macroglial, and microglial (macrophage) cell types within the grafts. Mitotic activity and histogenetic differentiation took place. Blood vessels filled with hematic cells were commonly present within the grafts. The walls of these vessels prevented the leakageofhorseradish peroxidase, suggesting the presence of a functional brain-blood barrier in the graft. These results indicate that it is possible to use a small animal model to study normal and pathological phenomena oniate fetal human neural tissues. Our group has already taken advantage of the model to achieve HIV infectivity offetal human brain outside the human body

De copistas y censuras. Una versión íntegra del memorial de 1637 del Conde Duque de Olivares

The critical edition of original texts is still one of the lesser developed fields in Early Modern historical scholarship. In this regard, the work of J.H. Elliot and J.F. de la Peña in editing some letters and memos of the Count-Duke of Olivares can be considered a milestone. In this article, we present the edition of a memorial dated in 1637 previously edited by Elliot and de la Peña but which departs from several copies of the document. Our source, instead, has been the original manuscript, unknown to these authors, which points out several issues missing in the copies. A thorough analysis of this document has led us to conclude that the missing parts may correspond with an act of censorship, which facilitated the response to Olivares’ policy. This clearly shows how the manipulation of texts can distort historians’ vision of reality.La edición de textos de época es una de las parcelas de la historia moderna menos atendida. En este sentido la obra de Elliott y de la Peña editando algunas cartas y memoriales del Conde Duque de Olivares puede considerarse un hito. En nuestro artículo planteamos la edición de uno de estos memoriales (1637) que estos autores ya habían editado pero acogiéndonos a un original por ellos desconocido y en el que se plantean otra serie de cosas que las copias no recogen. De la lectura detenida del mismo se deduce que las partes que faltan pueden responder a un ejercicio de censura encaminado a facilitar la respuesta a la política de Olivares en una muestra clara de cómo la manipulación de los textos puede conducir a los historiadores a una visión distorsionada de la realidad

Intraretinal Transplantation for Rod-Cell Replacement in Light-Damaged Retinas

Blindness from retinal disease is often the consequence of extensive damage to the photoreceptor cell population, while other cell types which form the neural retina are relatively spared. In this setting, transplantation of photoreceptor cells could offer hope for the restoration of some degree of visual function. We testd the feasibility of this approach by transplanting immature retinal cells into the eyes of adult rats affected by late stage phototoxic retinopathy, which are almost totally devoid of photoreceptor cells

Corneal nerve alterations in diabetes mellitus

The morphologic status of corneal innervation was studied in rats with streptozocin-induced diabetes. Animals were killed at 1, 4, 16, and 36 weeks. Corneal innervation was studied by light and electron microscopy using nonspecific cholinesterase reaction, gold chloride impregnation, and plastic-embedded sections. Increased irregularity in the periodicity of nerve fiber beading was observed in diabetic corneas with gold impregnation. Ultrastructural evidence of irregularities in the basal lamina of Schwann cells was demonstrated in 16- and 36-week-old diabetic animals, along with occasional axonal degeneration. These alterations constitute a constellation of early pathologic manifestations in the innervation of diabetic cornea. To our knowledge, this study represents the first demonstration of neural changes in diabetic corneas as well as nerve fiber changes in an avascular tissue in diabetes

Artificial Bee Colony optimization of Deep Convolutional Neural Networks in the context of Biomedical Imaging

Most efforts in Computer Vision focus on natural images or artwork, which differ significantly both in size and contents from the kind of data biomedical image processing deals with. Thus, Transfer Learning models often prove themselves suboptimal for these tasks, even after manual finetuning. The development of architectures from scratch is oftentimes unfeasible due to the vastness of the hyperparameter space and a shortage of time, computational resources and Deep Learning experts in most biomedical research laboratories. An alternative to manually defining the models is the use of Neuroevolution, which employs metaheuristic techniques to optimize Deep Learning architectures. However, many algorithms proposed in the neuroevolutive literature are either too unreliable or limited to a small, predefined region of the hyperparameter space. To overcome these shortcomings, we propose the Chimera Algorithm, a novel, hybrid neuroevolutive algorithm that integrates the Artificial Bee Colony Algorithm with Evolutionary Computation tools to generate models from scratch, as well as to refine a given previous architecture to better fit the task at hand. The Chimera Algorithm has been validated with two datasets of natural and medical images, producing models that surpassed the performance of those coming from Transfer Learning

New method for correcting beam-hardening artifacts in CT images via deep learning

Proceedings of the 16th Virtual International Meeting on Fully 3D Image Reconstruction in Radiology and Nuclear Medicine, 19-23 July 2021, Leuven, Belgium.Beam-hardening is the increase of the mean energy of an X-ray beam as it traverses a material. This effect produces two artifacts in the reconstructed image: cupping in homogeneous regions and dark bands among dense areas in heterogeneous regions. The correction methods proposed in the literature can be divided into post-processing and iterative methods. The former methods usually need a bone segmentation, which can fail in low-dose acquisitions, while the latter methods need several projections and reconstructions, increasing the computation time. In this work, we propose a new method for correcting the beamhardening artifacts in CT based on deep learning. A U-Net network was trained with rodent data for two scenarios: standard and low-dose. Results in an independent rodent study showed an optimum correction for both scenarios, similar to that of iterative approaches, but with a reduction of computational time of two orders of magnitude.This work has been supported by project "DEEPCT-CMUC3M", funded by the call "Programa de apoyo a la realización de proyectos interdisciplinares de I+D para jóvenes investigadores de la UC3M 2019-2020, Convenio Plurianual CAM - UC3M" and project "RADCOV19", funded by CRUE Universidades, CSIC and Banco Santander (Fondo Supera). The CNIC is supported by the Ministerio de Ciencia, Innovación y Universidades and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505)

De copistas y censuras. Una versión íntegra del memorial de 1637 del Conde Duque de Olivares

The critical edition of original texts is still one of the lesser developed fields in Early Modern historical scholarship. In this regard, the work of J.H. Elliot and J.F. de la Peña in editing some letters and memos of the Count-Duke of Olivares can be considered a milestone. In this article, we present the edition of a memorial dated in 1637 previously edited by Elliot and de la Peña but which departs from several copies of the document. Our source, instead, has been the original manuscript, unknown to these authors, which points out several issues missing in the copies. A thorough analysis of this document has led us to conclude that the missing parts may correspond with an act of censorship, which facilitated the response to Olivares’ policy. This clearly shows how the manipulation of texts can distort historians’ vision of reality

Posterior Segment Approach for Subretinal Transplantation or Injection in the Canine Model

A posterior segment approach for cell transplantation or injection into the subretinal space of the dog has been developed. Controlled penetration to the subretinal space was achieved using a 29-gauge injection cannula, either blunted or with a 30° sharpened bevel, and partially ensheathed with moveable plastic tubing. Depending on the injection volume used, the retina detached, and the fluid was reabsorbed within 1–3 weeks, although for smaller volumes the retina reattached within a matter of days. The optimal injection volume used was between 100 and 150 μl, or two injections of 55 μl each. By ophthalmoscopy following the surgery, it was possible to serially monitor the injection site and retinal bleb through fundus photography. Light microscopy demonstrates the distribution of stable, viable RPE cells in the subretinal space up to 6 months. The transplantation technique developed for the dog is atraumatic and free from any major surgical or clinical complications. It can be readily used to deliver cells or fluids to localized regions of the subretinal space

La viuda generosa : comedia original / escrita por Fermin del Rey

BNE zIND2000952390Datos de pie de imp. en colofónTexto a 2 col.Sig.: a-c4, d5En port. sello: "Se hallara en la Imprenta de Orga, calle de las Barcas, en Valencia, nº 13"El colofón aporta los precios de las comedias: 2 sueltas, en tomo de pasta 20, en pergamino 16, rústica 15 reales

Mejora del proceso de enseñanza-aprendizaje en ciclos formativos de grado superior mediante un nuevo material TIC

La presente comunicación tiene como finalidad la de dar a conocer algunas aplicaciones propuestas para los nuevos materiales didácticos TIC desarrollados en la Universidad de Murcia, útiles para ampliar el currículo y mejorar el proceso de enseñanza-aprendizaje de los alumnos de Ciclos Formativos de Grado Superior en las materias relacionadas con la Transmisión del Calor. Concretamente, esta comunicación describe aplicaciones de dichos materiales didácticos para el módulo de Certificación Energética de Edificios I del Ciclo Formativo Superior de Eficiencia Energética y Energía Solar Térmica. Con ello se da cumplimiento a los objetivos didácticos generales que se plantean para esta titulación, relacionados con los fenómenos de transmisión del calor en elementos pasivos mediante el uso del software de simulación PROCCA-09