Editorial: New insights into adult neurogenesis and neurodegeneration: challenges for brain repair

The formation of new neurons in the brain is probably one of the most controversial topics in the scientific community since in the 1960's Joseph Altman described for the first time that proliferating cells give rise to new neurons in the adult brain of rats and other mammals. This Research Topic includes 1 brief research report, 3 mini review, 4 review and 9 original research papers gathering different contributions highlighting new developments in the field of neurogenesis

J. H. Newman, hoy

Documentos del Instituto de Antropología y Ética, número 1

On Some Sampling-Related Frames in U-Invariant Spaces

This paper is concerned with the characterization as frames of some sequences in -invariant spaces of a separable Hilbert space H where U denotes an unitary operator defined on H ; besides, the dual frames having the same form are also found. This general setting includes, in particular, shift-invariant or modulation-invariant subspaces in L2(R) , where these frames are intimately related to the generalized sampling problem. We also deal with some related perturbation problems. In doing so, we need the unitary operator to belong to a continuous group of unitary operators

CCAAT/Enhancer binding protein β induces motility and invasion of glioblastoma cells through transcriptional regulation of the calcium binding protein S100A4

This work is licensed under a Creative Commons Attribution 3.0 License.We have previously shown that decreased expression of CCAAT/Enhancer binding protein β (C/EBPβ) inhibits the growth of glioblastoma cells and diminishes their transformation capacity and migration. In agreement with this, we showed that C/ EBPβ depletion decreases the mRNA levels of different genes involved in metastasis and invasion. Among these, we found S100 calcium binding protein A4 (S100A4) to be almost undetectable in glioblastoma cells deficient in C/EBPβ. Here, we have evaluated the possible role of S100A4 in the observed effects of C/EBPβ in glioblastoma cells and the mechanism through which S100A4 levels are controlled by C/EBPβ. Our results show that C/EBPβ suppression significantly reduced the levels of S100A4 in murine GL261 and human T98G glioblastoma cells. By employing an S100A4-promoter reporter, we observed a significant induction in the transcriptional activation of the S100A4 gene by C/EBPβ. Furthermore, overexpression of S100A4 in C/EBPβ- depleted glioblastoma cells reverses the enhanced migration and motility induced by this transcription factor. Our data also point to a role of S100A4 in glioblastoma cell invasion and suggest that the C/EBPβ gene controls the invasive potential of GL261 and T98G cells through direct regulation of S100A4. Finally, this study indicates a role of C/EBPβ on the maintenance of the stem cell population present in GL261 glioblastoma cells.This work was supported by MINECO (SAF2010–16365) and by Fundación Mutua Madrileña (to A.P.-C.). CIBERNED is funded by the Instituto de Salud Carlos III. D.A.-M. is a fellow of the MINECO.Peer Reviewe

La hidroxiapatita asociada al sulfato cálcico como material de substitución ósea. Aspectos biológicos.

La cirugía ortopédica y máxilo-facial necesitan realizar en muchas ocasiones resecciones masivas de tejido óseo. Esto ha hecho que se haya propuesto la utilización de materiales inertes como substitutos óseos, gracias a la habilidad que tienen de permitir la regeneración del hueso, tanto en el campo de la medicina como en el de la odontología. Nuestro trabajo tiene por objetivo estudiar un biomaterial compuesto de hidroxiapatita y sulfato cálcico como material de substitución ósea en forma de cilindros. Se han intervenido 75 animales de experimentación (conejo Albino de Nueva Zelanda), divididos en tres grupos, cada uno de ellos compuesto por 25 animales. En el grupo I o control, los animales fueron intervenidos quirúrgicamente realizándoseles una cavidad a nivel metafisodiafisario en el fémur sin realizar implantes. A los animales del grupo II y III se les realizó la misma intervención, pero se les implantó un cilindro de hidroxiapatita (HA) y sulfato cálcico a dos concentraciones diferentes, 50% - 50% y 70% - 30% respectivamente. El estudio ha demostrado una regeneración ósea de la cavidad rellenada a expensas de la rápida reabsorción del yeso, y de una lenta reabsorción de la hidroxiapatita.Peer Reviewe

Constellation design for multiuser non-coherent massive SIMO based on DMPSK modulation

Non-coherent (NC) schemes combined with massive antenna arrays are proposed to replace traditional coherent schemes in scenarios which require an excessive number of reference signals, since NC approaches avoid channel estimation and equalization. Differential M-ary phase shift keying is one of the most appealing NC schemes due to its implementation simplicity in realistic scenarios. However, the analytical constellation design for multiuser scenarios is intractable, as discussed in this paper. We propose to solve this problem by using optimization techniques relying on evolutionary computation. We design two approaches, namely Gaussian-approximated optimization and Monte-Carlo based optimization. They can provide both individual constellations for each user equipment and a bit mapping policy to minimize the bit error rate. We perform a complexity analysis and propose strategies for its reduction. We propose a set of constellations for different number of users and constellation sizes, and evaluate the link-level performance of some illustrative examples to verify that our solutions outperforms the existing ones. Finally, we show via simulations that NC outperforms the coherent schemes in high mobility and/or low signal-to-noise ratio scenarios.This work has received funding from the European Union Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie ETN TeamUp5G, grant agreement No.813391, and from Spanish National Project IRENE-EARTH (PID2020-115323RB-C33) (MINECO/AEI/FEDER, UE). The work of O. A. Dobre has been supported in part by the Natural Sciences and Engineering Research Council of Canada (NSERC), through its Discovery program

Experimental Type 2 Diabetes Induces Enzymatic Changes in Isolated Rat Enterocytes

Diabetes in humans and in experimental animals produces changes in the function and structure of the small intestine. The authors determined the activity of intestinal disaccharidases (maltase and sucrase) and of 6-phosphofructo-1-kinase (PFK-1) in enterocytes isolated from the small intestine of male Wistar rats (2.5 to 3 months old) with experimental nonobese type 2 diabetes, induced by streptozotocin (STZ) injection on the day of birth (n0-STZ) or on the 5th day of life (n5-STZ), with different degrees of hyperglycemia and insulinemia (n0-STZ and n5-STZ models). The glycemia (mmol/L) of the diabetic rats (n0-STZ: 8.77 ± 0.47; n5-STZ: 20.83 ± 0.63) was higher (P < .01) than that of the nondiabetic (ND) rats (5.99 ± 0.63); on the contrary, the insulinemia (ng/mL) was significantly lower in both n0-STZ (1.74 ± 0.53; P < .05) and n5-STZ (1.12 ± 0.44; P < .01) diabetic rats than in normal rats (3.77 ± 0.22). The sucrase and maltase activities (U/g protein) in diabetic rats (n0-STZ: 89 ± 9 and 266 ± 12; n5-STZ: 142 ± 23 and 451 ± 57) were significantly higher than those in the ND group (66 ± 5 and 228 ± 22). The PFK-1 activities (mU/mg protein) in the diabetic models (n0-STZ: 14.89 ± 1.51; n5-STZ: 13.35 ± 3.12) were significantly lower (P < .05) than in ND rats (20.54 ± 2.83). The data demonstrated enzymatic alterations in enterocytes isolated fromthe small intestine of n0-STZ rats that are greater (P < .05) than in the more hyperglycemic and hypoinsulinemic n5-STZ animals. The results also show that nonobese type 2–like diabetes in the rat produces modifications that favor an increase in glucose absorption rates

Modelization of anaerobic processes during co-digestion of slowly biodegradable substrates

The influence of the soluble substrates over the anaerobic processes has been extensively investigated, but little is known about the effects of particulate substrate. The biodegradation of these substrates starts with the hydrolytic step, this process is slower than the other ones involved in the biodegradation of particulate substrates and usually becomes the rate-limiting step. This study investigate the effect of the initial total solids (TS) concentration on the anaerobic co-digestion of two slowly biodegradable organic substrates. The wastes mixtures were prepared at different dilutions in the range from 10% to 28% TS. From these experiments it was observed that as TS concentration increased, the methane production decreased. These results were modelled and it was observed that neither hydrolysis nor fermentation stages controlled the methane production rate. Being a substrate inhibition event experienced at the methanogenic stage the responsible of the lower methane production when operating at high TS concentrations.La influencia de los sustratos solubles sobre los procesos anaeróbicos se ha investigado extensamente, pero se sabe poco acerca de los efectos del sustrato particulado. La biodegradación de estos sustratos comienza con el paso hidrolítico, este proceso es más lento que los otros involucrados en la biodegradación de sustratos particulados y generalmente se convierte en el paso limitante de la velocidad. Este estudio investiga el efecto de la concentración inicial de sólidos totales (TS) sobre la codigestión anaeróbica de dos sustratos orgánicos lentamente biodegradables. Las mezclas de desechos se prepararon a diferentes diluciones en el rango de 10% a 28% de TS. A partir de estos experimentos, se observó que a medida que aumentaba la concentración de TS, la producción de metano disminuía. Estos resultados se modelaron y se observó que ni las etapas de hidrólisis ni de fermentación controlaban la tasa de producción de metano. Siendo un evento de inhibición del sustrato experimentado en la etapa metanogénica el responsable de la menor producción de metano cuando se opera a altas concentraciones de TS

Two-dimensional distributed feedback lasers with thermally-nanoimprinted perylenediimide-containing films

Two-dimensional (2D) distributed feedback (DFB) lasers with gratings imprinted by thermal nanoimprint lithography on the active film are reported. They show thresholds for lasing of ∼10 kW/cm2, similar to the most efficient imprinted DFB lasers reported; and long operational lifetimes (under ambient conditions) of ∼12 × 104 pump pulses. The key for their successful operation has been the selection of a highly efficient and stable dye, perylene orange (PDI-O), and a proper matrix to host it, the fluoro-modified thermoplastic resist mr-I7030R, which has enabled 2D imprinting while preserving the dye optical properties. The use of the UV-curable resist SU8 as an alternative matrix for PDI-O to be imprinted by combined nanoimprint and photolithography was also investigated, and was concluded to be unsuccessful due to severe photoluminescence quenching. By replacing PDI-O with Rhodamine 6G, lasers with reasonable thresholds, but with significantly inferior operational lifetimes in comparison to PDI-O/mr-I7030R devices, were obtained.We thank support from the Spanish Government (MINECO) and the European Community (FEDER) through Grants MAT2011-28167-C02 and MAT2015-66586-R, as well as to the University of Alicante. M.M-V. has been partly supported by a MINECO FPI fellowship (no. BES-2009-020747) and by a Junta de Castilla y León grant (no. SA046U16)