Sistema embebido para el control de carga de baterías en un vehículo eléctrico híbrido ligero (EPISOL)

El presente trabajo es resultado de un proyecto para desarrollar un vehículo híbrido con varias fuentes de carga de baterías. Su objetivo es contribuir a reducir las emisiones debidas al tráfico urbano de vehículos, tendencia muy buscada en los últimos años, donde se han acometido importantes proyectos de investigación orientados al desarrollo de sistemas de propulsión y combustibles alternativos a los actualmente mayoritarios. A continuación se describe el sistema embebido de control realizado, en el que un microcontrolador se encarga del ajuste de la carga de las baterías, a partir de las contribuciones de una pila de combustible, unos paneles solares y un generador conectado a un motor de combustión interna, para conseguir el mayor rendimiento energético y lograr unos niveles de emisiones casi nulos

Definición de la gestión energética de un vehículo híbrido basada en la simulación del funcionamiento de los componentes del sistema propulsor en las condiciones de operación de diseño

La tendencia actual hacia el incremento de la movilidad en las sociedades más avanzadas va en contradicción con criterios de control de la contaminación local y la explotación de los recursos de combustible. Entre las soluciones planteadas, se encuentran los vehículos híbridos. En este artículo se presenta la definición y simulación de la gestión energética de uno de estos vehículos, a partir de las condiciones de operación. El vehículo híbrido diseñado en su totalidad combina propulsión con un motor eléctrico alimentado por baterías y un motor térmico, incluyéndose, además, paneles solares, así como carga externa por red eléctrica. Se han desarrollado modelos de simulación de los componentes y su integración. Analizando el campo de aplicación del vehículo, se ha planteado un ciclo de conducción a partir de ciclos estándar. Con el modelo, se ha analizado la idoneidad de diferentes estrategias de control de la energía, considerando diversas condiciones operativas

CHO/LY-B Cell Growth under Limiting Sphingolipid Supply: Correlation between Lipid Composition and Biophysical Properties of Sphingolipid-Restricted Cell Membranes

Sphingolipids (SL) are ubiquitous in mammalian cell membranes, yet there is little data on the behavior of cells under SL- restriction conditions. LY- B cells derive from a CHO linein whichserine palmitoyl transferase (SPT), thus de novo SL synthesis, is suppressed, while maintaining the capacity of taking up and metabolizing exogenous sphingoid bases from the culture medium. In this study, LY- B cells were adapted to grow in a fetal bovine serum (FBS)- deficient medium to avoid external uptake of li-pids. The lowest FBS concentration that allowed LY- B cell growth, though at a slow rate, under our conditions was 0.04%, that is, 250- fold less than the standard (10%) concentration. Cells grown under limiting SL concentrations remained viable for at least 72hours. Enriching with sphingomyelin the SL- deficient medium allowed the recovery of growth rates analogous to those of control LY- B cells. Studies in-cluding whole cells, plasma membrane preparations, and derived lipid vesicles were carried out. Laurdan fluorescence was recorded to measure membrane molecular order, showing a significant decrease in the rigidity of LY- B cells, not only in plasma membrane but also in whole cell lipid extract, as a result of SL limitation in the growth medium. Plasma membrane preparations and whole cell lipid extracts were also studied using atomic force microscopy in the force spectroscopy mode. Force measurements demonstrated that lower breakthrough forces were required to pen-etrate samples obtained from SL- poor LY- B cells than those obtained from control cells. Mass- spectroscopic analysis was also a helpful tool to understand the rear-rangement undergone by the LY- B cell lipid metabolism. The most abundant SL in LY- B cells, sphingomyelin, decreased by about 85% as a result of SL limitation in the medium, the bioactive lipid ceramide and the ganglioside precursor hexosylcera-mide decreased similarly, together with cholesterol. Quantitative SL analysis showed that a 250- fold reduction in sphingolipid supply to LY- B cells led only to a sixfold decrease in membrane sphingolipids, underlining the resistance to changes in com-position of these cells. Plasma membrane compositions exhibited similar changes, at least qualitatively, as the whole cells with SL restriction. A linear correlation was observed between the sphingomyelin concentration in the membranes, the degree of lipid order as measured by laurdan fluorescence, and membrane breakthrough forces assessed by atomic force microscopy. Smaller, though significant, changes were also detected in glycerophospholipids under SL- restriction conditions.This work was supported in part by grants from the Spanish Ministry of Economy (grant FEDER MINECO PGC2018-099857-B-I00) and the Basque Government (grants No. IT1264-19 and IT1270-19), as well as Fundación Biofísica Bizkaia and the Basque Excellence Research Centre (BERC) program of the Basque Government, and by the Swiss National Science Foundation (310030-184949

Patches and Blebs: A Comparative Study of the Composition and Biophysical Properties of Two Plasma Membrane Preparations from CHO Cells

This study was aimed at preparing and characterizing plasma membranes (PM) from Chinese Hamster Ovary (CHO) cells. Two methods of PM preparation were applied, one based on adhering cells to a poly-lysine-coated surface, followed by hypotonic lysis and removal of intracellular components, so that PM patches remain adhered to each other, and a second one consisting of bleb induction in cells, followed by separation of giant plasma membrane vesicles (GPMV). Both methods gave rise to PM in sufficient amounts to allow biophysical and biochemical characterization. Laurdan generalized polarization was used to measure molecular order in membranes, PM preparations were clearly more ordered than the average cell membranes (GP ≈0.450 vs. ≈0.20 respectively). Atomic force microscopy was used in the force spectroscopy mode to measure breakthrough forces of PM, both PM preparations provided values in the 4–6 nN range, while the corresponding value for whole cell lipid extracts was ≈2 nN. Lipidomic analysis of the PM preparations revealed that, as compared to the average cell membranes, PM were enriched in phospholipids containing 30–32 C atoms in their acyl chains but were relatively poor in those containing 34–40 C atoms. PM contained more saturated and less polyunsaturated fatty acids than the average cell membranes. Blebs (GPMV) and patches were very similar in their lipid composition, except that blebs contained four-fold the amount of cholesterol of patches (≈23 vs. ≈6 mol% total membrane lipids) while the average cell lipids contained 3 mol%. The differences in lipid composition are in agreement with the observed variations in physical properties between PM and whole cell membranes.This work was supported in part by grant PGC2018-099857-B-I00 (MCI/AEI/FEDER, UE) and grants IT1264-19 and IT1270-19 from the Basque Government

Plasma membrane effects of sphingolipid-synthesis inhibition by myriocin in CHO cells: a biophysical and lipidomic study

[EN] Suppression of a specific gene effect can be achieved by genetic as well as chemical methods. Each approach may hide unexpected drawbacks, usually in the form of side effects. In the present study, the specific inhibitor myriocin was used to block serine palmitoyltransferase (SPT), the first enzyme in the sphingolipid synthetic pathway, in CHO cells. The subsequent biophysical changes in plasma membranes were measured and compared with results obtained with a genetically modified CHO cell line containing a defective SPT (the LY-B cell line). Similar effects were observed with both approaches: sphingomyelin values were markedly decreased in myriocin-treated CHO cells and, in consequence, their membrane molecular order (measured as laurdan general polarization) and mechanical resistance (AFM-measured breakthrough force values) became lower than in the native, non-treated cells. Cells treated with myriocin reacted homeostatically to maintain membrane order, synthesizing more fully saturated and less polyunsaturated GPL than the non-treated ones, although they achieved it only partially, their plasma membranes remaining slightly more fluid and more penetrable than those from the control cells. The good agreement between results obtained with very different tools, such as genetically modified and chemically treated cells, reinforces the use of both methods and demonstrates that both are adequate for their intended use, i.e. the complete and specific inhibition of sphingolipid synthesis in CHO cells, without apparent unexpected effects.The authors are grateful to Dr. X. Contreras for his critical reading of the manuscript. This work was supported in part by the Spanish Ministerio de Ciencia e Innovacion (MCI), Agencia Estatal de Investigacion (AEI) and Fondo Europeo de Desarrollo Regional (FEDER) (grant No. PGC2018-099857-B-I00), by the Basque Government (Grants No. IT1264-19, IT1196-19 and IT1270-19), by the Fundacion Biofisica Bizkaia and by the Basque Excellence Research Centre (BERC) program of the Basque Government, and by the Swiss National Science Foundation (310030-184949)

Distribution of the transcription factor islet-1 in the central nervous system of nonteleost actinopterygian fish: Relationshipwith cholinergic and catecholaminergic systems

Islet-1 (Isl1) is one of the most conserved transcription factors in the evolution of vertebrates, due to its continuing involvement in such important functions as the differentiation of motoneurons, among other essential roles in cell fate in the forebrain. Although its functions are thought to be similar in all vertebrates, the knowledge about the conservation of its expression pattern in the central nervous system goes as far as teleosts, leaving the basal groups of actinopterygian fishes overlooked, despite their important phylogenetic position. In order to assess the extent of its conservation among vertebrates, we studied its expression pattern in the central nervous system of selected nonteleost actinopterygian fishes. By means of immunohistochemical techniques, we analyzed the Isl1 expression in the brain, spinal cord, and sensory ganglia of the cranial nerves of young adult specimens of the cladistian species Polypterus senegalus and Erpetoichthys calabaricus, the chondrostean Acipenser ruthenus, and the holostean Lepisosteus oculatus. We also detected the presence of the transcription factor Orthopedia and the enzymes tyrosine hydroxylase (TH) and choline acetyltransferase (ChAT) to better locate all the immunoreactive structures in the different brain areas and to reveal the possible coexpression with Isl1. Numerous conserved features in the expression pattern of Isl1 were observed in these groups of fishes, such as populations of cells in the subpallial nuclei, preoptic area, subparaventricular and tuberal hypothalamic regions, prethalamus, epiphysis, cranial motor nuclei and sensory ganglia of the cranial nerves, and the ventral horn of the spinal cord. Double labeling of TH and Isl1 was observed in cells of the preoptic area, the subparaventricular and tuberal hypothalamic regions, and the prethalamus, while virtually all motoneurons in the hindbrain and the spinal cord coexpressed ChAT and Isl1. Altogether, these results show the high degree of conservation of the expression pattern of the transcription factor Isl1, not only among fish, but in the subsequent evolution of vertebrates.Depto. de Biología CelularFac. de Ciencias BiológicasTRUEMinisterio de Ciencia e Innovación (MICINN)Universidad Complutense de Madrid (UCM)pu

Expression of SATB1 and SATB2 in the brain of bony fishes: what fish reveal about evolution

Satb1 and Satb2 belong to a family of homeodomain proteins with highly conserved functional and regulatory mechanisms and posttranslational modifications in evolution. However, although their distribution in the mouse brain has been analyzed, few data exist in other non-mammalian vertebrates. In the present study, we have analyzed in detail the sequence of SATB1 and SATB2 proteins and the immunolocalization of both, in combination with additional neuronal markers of highly conserved populations, in the brain of adult specimens of different bony fish models at key evolutionary points of vertebrate diversification, in particular including representative species of sarcopterygian and actinopterygian fishes. We observed a striking absence of both proteins in the pallial region of actinopterygians, only detected in lungfish, the only sarcopterygian fish. In the subpallium, including the amygdaloid complex, or comparable structures, we identified that the detected expressions of SATB1 and SATB2 have similar topologies in the studied models. In the caudal telencephalon, all models showed significant expression of SATB1 and SATB2 in the preoptic area, including the acroterminal domain of this region, where the cells were also dopaminergic. In the alar hypothalamus, all models showed SATB2 but not SATB1 in the subparaventricular area, whereas in the basal hypothalamus the cladistian species and the lungfish presented a SATB1 immunoreactive population in the tuberal hypothalamus, also labeled with SATB2 in the latter and colocalizing with the gen Orthopedia. In the diencephalon, all models, except the teleost fish, showed SATB1 in the prethalamus, thalamus and pretectum, whereas only lungfish showed also SATB2 in prethalamus and thalamus. At the midbrain level of actinopterygian fish, the optic tectum, the torus semicircularis and the tegmentum harbored populations of SATB1 cells, whereas lungfish housed SATB2 only in the torus and tegmentum. Similarly, the SATB1 expression in the rhombencephalic central gray and reticular formation was a common feature. The presence of SATB1 in the solitary tract nucleus is a peculiar feature only observed in non-teleost actinopterygian fishes. At these levels, none of the detected populations were catecholaminergic or serotonergic. In conclusion, the protein sequence analysis revealed a high degree of conservation of both proteins, especially in the functional domains, whereas the neuroanatomical pattern of SATB1 and SATB2 revealed significant differences between sarcopterygians and actinopterygians, and these divergences may be related to the different functional involvement of both in the acquisition of various neural phenotypes.Depto. de Biología CelularFac. de Ciencias BiológicasTRUEMinisterio de Ciencia e Innovación (grant no. PID2020- 112681GB100), and the Santander/Complutense University of Madrid, Grant/Award Number: PR108/20-17Universidad Complutense de Madrid (UCM) /Banco de Santanderpu

Bisphenol-A Induces Podocytopathy With Proteinuria in Mice

Bisphenol-A, a chemical used in the production of the plastic lining of food and beverage containers, can be found in significant levels in human fluids. Recently, bisphenol-A has been associated with low-grade albuminuria in adults as well as in children. Since glomerular epithelial cells (podocytes) are commonly affected in proteinuric conditions, herein we explored the effects of bisphenol-A on podocytes in vitro and in vivo. On cultured podocytes we first observed that bisphenol-A?at low or high concentrations?(10?nM and 100?nM, respectively) was able to induce hypertrophy, diminish viability, and promote apoptosis. We also found an increase in the protein expression of TGF-?1 and its receptor, the cyclin-dependent kinase inhibitor p27Kip1, as well as collagen-IV, while observing a diminished expression of the slit diaphragm proteins nephrin and podocin. Furthermore, mice intraperitoneally injected with bisphenol-A (50?mg/Kg for 5 weeks) displayed an increase in urinary albumin excretion and endogenous creatinine clearance. Renal histology showed mesangial expansion. At ultrastructural level, podocytes displayed an enlargement of both cytoplasm and foot processes as well as the presence of condensed chromatin, suggesting apoptosis. Furthermore, immunohistochemistry for WT-1 (specific podocyte marker) and the TUNEL technique showed podocytopenia as well as the presence of apoptosis, respectively. In conclusion, our data demonstrate that Bisphenol-A exposure promotes a podocytopathy with proteinuria, glomerular hyperfiltration and podocytopenia. Further studies are needed to clarify the potential role of bisphenol-A in the pathogenesis as well as in the progression of renal diseases.Ministerio de Ciencia e InnovaciónInstituto de Salud Carlos IIIThe Eugenio Rodríguez Pascual Foundatio

Kv1.3 channels can modulate cell proliferation during phenotypic switch by an ion-flux independent mechanism

Producción CientíficaObjective: Phenotypic modulation of vascular smooth muscle cells has been associated with a decreased expression of all voltage-dependent potassium channel (Kv)1 channel encoding genes but Kcna3 (which encodes Kv1.3 channels). In fact, upregulation of Kv1.3 currents seems to be important to modulate proliferation of mice femoral vascular smooth muscle cells in culture. This study was designed to explore if these changes in Kv1 expression pattern constituted a landmark of phenotypic modulation across vascular beds and to investigate the mechanisms involved in the proproliferative function of Kv1.3 channels. Methods and Results: Changes in Kv1.3 and Kv1.5 channel expression were reproduced in mesenteric and aortic vascular smooth muscle cells, and their correlate with protein expression was electrophysiologicaly confirmed using selective blockers. Heterologous expression of Kv1.3 and Kv1.5 channels in HEK cells has opposite effects on the proliferation rate. The proproliferative effect of Kv1.3 channels was reproduced by “poreless” mutants but disappeared when voltagedependence of gating was suppressed. Conclusion: These findings suggest that the signaling cascade linking Kv1.3 functional expression to cell proliferation is activated by the voltage-dependent conformational change of the channels without needing ion conduction. Additionally, the conserved upregulation of Kv1.3 on phenotypic modulation in several vascular beds makes this channel a good target to control unwanted vascular remodeling.Instituto de Salud Carlos III (grant R006/009)Ministerio de Ciencia, Innovación y Universidades (grant BFU2010-15898)Junta de Castilla y León (grant VA094A11-2