Análisis comparativo de modelos de propagación en la telefonía móvil en la banda de 1900 MHz (LTE) a través de mediciones de campo eléctrico en la ciudad de Ambato

El presente artículo ofrece un análisis comparativo de los modelos de propagación Hata Extendido, SUI con factor de corrección de frecuencia y Ericsson 9999, en los sistemas de telefonía móvil que operan en la banda de 1900 MHz (LTE) a través de mediciones de campo eléctrico con la finalidad de establecer una recomendación de un modelo de propagación existente que se ajuste a las características del casco urbano de la ciudad de Ambato. Inicialmente se ubicaron cinco estaciones base, luego se escogieron dos estaciones base que trabajan en la banda y tecnología antes mencionada. Posteriormente se trazaron 4 limites radiales en los alrededores de las estaciones base y se realizaron 4 campañas de mediciones de campo eléctrico con el equipo Narda SRM-3006 en un total de 48 puntos por 6 minutos por punto. Además, se determinó las coordenadas de los puntos de medición mediante el equipo Spectra Precision Mobile Mapper 50 donde se obtiene las distancias y alturas de terreno con gran precisión, con los datos recolectados se realizó el cálculo de las pérdidas de propagación para la obtención del campo eléctrico teórico de cada modelo de propagación. Para evaluar qué modelo se ajusta más a las mediciones se realizó una comparación de valores de campo eléctrico medido con respecto a los valores de campo eléctrico teórico de cada modelo, mediante una comparación del RMSE. Finalmente se concluyó que el modelo SUI con factor de corrección de frecuencia es el que tiene mejor ajuste al entorno urbano de la ciudad de Ambato

Enhancing adult hippocampal neurogenesis with lysophosphatidic acid: a proposal for erasing cocaine contextual memory

Stimulating adult hippocampal neurogenesis (AHN) has been uncovered as a promising approach in the manipulation of retrograde memories. This work aims to study whether increasing AHN with lysophosphatidic acid (LPA, an endogenous lysophospholipid with proneurogenic actions) promotes the forgetting of previously established cocaine-contextual associations. C57BL/6J mice previously trained in a cocaine-induced conditioned place preference (CPP) paradigm were submitted to 23 days of withdrawal, during which they received repeated intracerebroventricular infusions of LPA, ki16425 (a selective LPA1/3 receptors antagonist), or vehicle solution. Then, CPP maintenance was assessed, and the causal role of AHN in this process was evaluated using a mediation analysis. In a complementary experiment, wild-type and LPA1-null mice were acutely infused with LPA or ki16425 to determine the involvement of the LPA1 receptor in the in vivo proneurogenic actions of LPA. The chronic LPA treatment significantly weakened the long-term retention of a previously acquired cocaine-CPP memory, an effect clearly mediated by a LPA-induced increase in the number of adult-born dentate granule cells. In contrast, the ki16425-treated mice displayed aberrant responses of initially decreased CPP retention that progressively increased CPP across the extinction sessions, in absence of effects on AHN. The histological studies suggested that the proneurogenic actions of LPA were related to the enhancement of cell proliferation and critically depended on the LPA1 receptor function. Our results suggest that the LPA/LPA1-pathway acts as a potent in vivo modulator of AHN, and highlight the usefulness of a post-learning increase of adult-born hippocampal neurons as a strategy to promote the forgetting of cocaine-context associations.Plan Propio de Investigación y Transferencia. Campus de Excelencia Internacional Andalucía Tech. Spanish Ministry of Economy and Competitiveness (Agencia Estatal de Investigación), co‐funded by the European Research Development Fund (AEI/FEDER, UE) (PSI2013‐44901‐P and PSI2017‐82604‐R to L.J.S. and PSI2015‐73156‐JIN to E.C.O.); by the National System of Health‐Instituto de Salud Carlos III, which is co‐funded by AEI/FEDER, UE (Red de Trastornos Adictivos; RD16/0017/0001 to F.R.d.F.); and by the Andalusian R&D&I Programme, Regional Ministry of Economy and Knowledge (PAIDI CTS643 to G.E.T.). D.L.G.M. hold a FPU grant from the Spanish Ministry of Education, Culture and Sports (FPU13/04819 ). F.R.d.F. and G.E.T. are supported by Nicolas Monardes Programme, from the Andalusian Regional Ministry of Health. E.C.O. holds a ‘Jóvenes Investigadores’ grant (code: PSI2015‐73156‐JIN) from the Spanish Ministry of Economy and Competitiveness (Agencia Estatal de Investigación), which is co‐funded by the AEI/FEDER, UE

NOA36 Protein Contains a Highly Conserved Nucleolar Localization Signal Capable of Directing Functional Proteins to the Nucleolus, in Mammalian Cells

NOA36/ZNF330 is an evolutionarily well-preserved protein present in the nucleolus and mitochondria of mammalian cells. We have previously reported that the pro-apoptotic activity of this protein is mediated by a characteristic cysteine-rich domain. We now demonstrate that the nucleolar localization of NOA36 is due to a highly-conserved nucleolar localization signal (NoLS) present in residues 1–33. This NoLS is a sequence containing three clusters of two or three basic amino acids. We fused the amino terminal of NOA36 to eGFP in order to characterize this putative NoLS. We show that a cluster of three lysine residues at positions 3 to 5 within this sequence is critical for the nucleolar localization. We also demonstrate that the sequence as found in human is capable of directing eGFP to the nucleolus in several mammal, fish and insect cells. Moreover, this NoLS is capable of specifically directing the cytosolic yeast enzyme polyphosphatase to the target of the nucleolus of HeLa cells, wherein its enzymatic activity was detected. This NoLS could therefore serve as a very useful tool as a nucleolar marker and for directing particular proteins to the nucleolus in distant animal species

A cross-sectional study to assess the level of satisfaction with virtual education in Peruvian medical students

"Objectives: Education has totally changed in the context of the pandemic. Therefore, the objective of the present study was to evaluate the factors associated with the level of satisfaction with virtual education in Peruvian medical students during COVID-19. Methods: Analytical and cross-sectional study, based on an online survey of students nationwide. We use previously validated instruments to measure the level of satisfaction and stress (EPP-10-c) of students with virtual education. For the associated factors, adjusted prevalence ratios (PR) were estimated using Poisson regression. Results: Of the 1,878 students surveyed, the median age was 21 years, 57.8% (1,086) were women, 34.8% (654) had a high level of satisfaction with virtual education and 10.7% (202) presented high levels of stress. The factors associated with a low level of satisfaction were attending the fifth year of study, the partial and non-virtual adaptation of the university to virtual education, and a high level of stress. On the other hand, the factors associated with a high level of satisfaction were the education platform used and the study method used. Conclusion: Seven out of 10 students presented a low level of satisfaction with virtual education, 1 out of 10 presented a high level of stress. The factors associated with the low level of satisfaction were attending the fifth year of study, the non-virtual and partial adaptation of the university to virtual education, and the high level of stress.

More adult-born dentate gyrus neurons to weaken cocaine-related retrograde memories: an in vivo strategy employing exogenous lysophosphatidic acid

The post-training enhancement of adult hippocampal neurogenesis (AHN) has been receiving growing interest as a potential method to manipulate retrograde memories. Recent hypothesis suggest that the addition of adult-born dentate granule cells might promotes remodeling of pre-existing hippocampal circuits, which might both clear cocaine-related memories and facilitate the learning of new adaptive information. Here, we study the effect of stimulating AHN in vivo with exogenous lysophosphatidic acid (LPA) on the maintenance of retrograde cocaine-contextual associative memories. Male C57BL/6J mice trained in a cocaine-induced Conditioned Place Preference (CPP) model were later submitted to repeated intracerebroventricular (i.c.v.) injections of LPA, Ki16425 or vehicle solution during withdrawal. Afterwards, the long-term persistence of the cocaine-CPP was assessed and the mediational role of AHN in this process was evaluated. In addition, wild-type and mice lacking the LPA1 receptor received a single i.c.v. injection of LPA, Ki16425 or vehicle to assess the role of the LPA1 receptor in the LPA-induced increase of AHN. Our results revealed that the chronic administration of LPA decreased the retention of a previously acquired cocaine-induced CPP. This effect was mediated by an LPA-induced increase of AHN. In contrast, mice treated with Ki16425 showed reduced cocaine-CPP retention, but they increased their preference for the cocaine-paired compartment throughout CPP extinction. Besides, no effects of Ki16425 on AHN were found. Immunohistochemical studies suggested that LPA stimulated cell proliferation and promoted neuronal maturation with a key role of the LPA1 receptor. These findings emphasize the relevance of LPA and its LPA1 receptor as an in vivo modulator of AHN and the utility of the post-training increase of adult-born hippocampal neurons to weaken cocaine-context associations.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Lysophosphatidic acid-induced increase in adult hippocampal neurogenesis facilitates the forgetting of cocaine-contextual memory

Author manuscriptErasing memories of cocaine-stimuli associations might have important clinical implications for addiction therapy. Stimulating hippocampal plasticity by enhancing adult hippocampal neurogenesis (AHN) is a promising strategy because the addition of new neurons may not only facilitate new learning but also modify previous connections and weaken retrograde memories. To investigate whether increasing AHN prompted the forgetting of previous contextual cocaine associations, mice trained in a cocaine-induced conditioned place preference (CPP) paradigm were administered chronic intracerebroventricular infusions of lysophosphatidic acid (LPA, an endogenous lysophospholipid with pro-neurogenic actions), ki16425 (a LPA1/3 receptor antagonist), or a vehicle solution, and they were tested 23 days later for CPP retention and extinction. The results of immunohistochemical experiments showed that the LPA-treated mice exhibited reduced long-term CPP retention and an ~two-fold increase in the number of adult-born hippocampal cells that differentiated into mature neurons. Importantly, mediation analyses confirmed a causal role of AHN in reducing CPP maintenance. In contrast, the ki16425-treated mice displayed aberrant responses, with initially decreased CPP retention that progressively increased across the extinction sessions, leading to no effect on AHN. The pharmacological treatments did not affect locomotion or general exploratory or anxiety-like responses. In a second experiment, normal and LPA1 receptor-deficient mice were acutely infused with LPA, which revealed that LPA1-mediated signaling was required for LPA-induced proliferative actions. These results suggest that the LPA/LPA1-pathway acts as a potent in vivo modulator of AHN and highlight the potential usefulness of pro-AHN strategies to treat aberrant cognition in those addicted to cocaine.This study was funded by grants from the Spanish Ministry of Economy and Competitiveness (Agencia Estatal de Investigación), which is cofunded by the European Research Development Fund AEI/FEDER, UE- (PSI2013-44901-P and PSI2017-82604-R to LJS and PSI2015-73156-JIN to ECO); by the National System of Health-Instituto de Salud Carlos III, which is co-funded by AEI/FEDER, UE (Red de Trastornos Adictivos; RD16/0017/0001 to FRdF); and by the Andalusian R&D&I Programme, Regional Ministry of Economy and Knowledge (PAIDI CTS643 to GET). DLGM and RDMF hold FPU grants from the Spanish Ministry of Education, Culture and Sports (FPU13/04819 and FPU14-01610, respectively). CRV received a ‘Plan Propio’ grant from the University of Malaga. FJP and AS hold ‘Miguel Servet’ grants (CP14/00212 and CP14/00173, respectively) from the National System of Health-Instituto de Salud Carlos III, which is co-funded by AEI/FEDER, UE. FRdF and GET are supported by Nicolas Monardes Programme, from the Andalusian Regional Ministry of Health. ECO holds a ‘Jóvenes Investigadores’ grant (code: PSI2015- 73156-JIN) from the Spanish Ministry of Economy and Competitiveness (Agencia Estatal de Investigación) which is co-funded by the European Research Development Fund (AEI/FEDER, UE)

Socio-emotional strengths against psychopathology and suicidal ideation in fear of COVID-19

Coronavirus disease (COVID-19) has caused a global health crisis. It also leads to different types of psychosocial problems in society as a result of preventive health measures and the disease itself. Among others, psychopathological symptoms and suicide behaviors have increased. The PsicorecurSOS COVID-19 online protocol was designed. At baseline, 1020 Spanish adults were assessed, during confinement, for sociodemographics, fear of COVID-19, anxious-depressive symptoms, covitality, and suicidal ideation. Reliability, descriptive, and frequency analyses were carried out, and the computer tool SPSS PROCESS was used to carry out a conditional process analysis (model 59). A total of 595 participants were included (58.30% response rate from baseline; mean age = 37.18 [SD = 13.30]; 72.44% female). Regarding suicidal ideation, 12% responded differently to “never,” 19.3% exceeded the cutoff point on the anxiety scale, and 24% on the depression scale. Moderate mediation analysis explained 27% of the variance in suicidal ideation. In addition, the indirect effect of moderate mediation was significant (b = −.004, SE = .002 with the presence of covitality; and b = .01, SE = .003 absence of covitality). Sex and age did not influence the overall outcome of the model. The data from this study can serve as a starting point for generating social and health treatment initiatives based on self-examination of anxiety-depressive symptoms and increasing socio-emotional skills in order to prevent and alleviate the psychosocial effects of the pandemic.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature

LPA1/3 receptor antagonist KI16425 as a novel treatment for the neurobehavioural effects of the ethanol

Aims. The lysophosphatidic acid (LPA) is an ubiquitous lysophospholipid that acts through G-protein coupled receptors (LPA1-6), and it is involved in the modulation of emotional and motivational behaviors. Recent literature suggests a relevant role of the LPA signaling system in alcoholism, specially through the LPA1 receptor. This work aims to elucidate whether systemic LPA1/3 receptor blockade with ki16425 would modulate ethanol effects on the brain and behavior. Methods. This study consisted of four experiments assessing the effect of intraperitoneal ki16425 administration (20 mg/kg) on ethanol-related behaviors. Male Wistar rats or mice (Swiss, C57BL/6J or hybrid C57BL/6J×129X1/SvJ background) were employed in various procedures: I) oral ethanol selfadministration; II) loss of righting reflex; III) ethanol-induced conditioned place preference (CPP) and IV) ethanol-withdrawal behavioral symptoms (by assessing nest building, physical signs and spatial working memory). Immunohistochemistry was carried out in order to evaluate basal neuronal activity (c-Fos) in the medial prefrontal cortex (mPFC) and in the hippocampus, as well as adult hippocampal neurogenesis (AHN) using proliferating cell nuclear antigen (PCNA) and doublecortin (DCX) markers. Results. Systemic Ki16425 administration reduced oral self-administration of ethanol in previously trained rats. Likewise, ki16425 pretreatment in mice attenuated the sedation induced by ethanol, blocked ethanol rewarding effect in a CPP paradigm and reduced behavioral symptoms induced by ethanol withdrawal. Immunohistochemistry revealed a protective effect of ki16425 against ethanol actions on basal neuronal activity in the mPFC and on AHN. Conclusions. Our results suggest a potential usefulness of systemic LPA1/3 receptors antagonists as a novel treatment for alcohol-related disorders.Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech