bluuebunny/crossref_metadata_2025_split huggingface dataset:
La comunicación de boca en boca electrónica en los medios sociales. Análisis de sus antecedentes / Electronic word of mouth communication in the social media. Analysis of its background
Authors: Sarmiento Guede José Ramón , Rodríguez Terceño José 
Published: April 2018

En los últimos años, la comunicación de boca en boca electrónica ha desarrollado un crecimiento exponencial debido a los medios sociales y a los avances producidos en el comercio electrónico. Un incremento que ha venido acompañado por una mayor percepción de los fenómenos asociados a ella, como la profusión de informaciones falsas, la falta de comprobación de las informaciones, imprecisión, manipulación y generación espontánea de movimientos digitales o incluso ciudadanos, todo lo cual se ha quedado globalmente incluido bajo el nombre genérico de “Post-verdad”. Ante este contexto, el presente trabajo se ha marcado como objetivo principal identificar las dimensiones que tienen relación e influyen de una manera directa en el desarrollo de la comunicación de boca en boca electrónica. Para ello, se ha utilizado en la metodología la técnica de la entrevista en profundidad y la técnica de la encuesta online, dicha encuesta se aplicó a usuarios de los medios sociales en toda España. Para analizar los resultados, se recurrió al modelo de regresión lineal. Como conclusión, podemos afirmar que las dimensiones de la percepción de calidad, la percepción de valor y la satisfacción que los usuarios desarrollan en los medios sociales tiene una influencia directa en la comunicación de boca en boca electrónica.
Peptidergic Modulation of Intrathalamic Circuit ActivityIn Vitro: Actions of Cholecystokinin
Authors: Cox Charles L. , Huguenard John R. , Prince David A. 
Published: April 2018

Cholecystokinin (CCK)-mediated actions on intrathalamic rhythmic activities were examined in anin vitrorat thalamic slice preparation. Single electrical stimuli in the thalamic reticular nucleus (nRt) evoked rhythmic activity (1–15 sec duration) in nRt and the adjacent ventrobasal nucleus (VB). Low CCK concentrations (20–50 nm) suppressed rhythmic oscillations in 43% of experiments but prolonged such activities in the remaining slices. Higher CCK concentrations (100–400 nm) had a predominantly antioscillatory effect.Suppression of oscillations was associated with a relatively large membrane depolarization of nRt neurons that changed their firing mode from phasic (burst) to tonic (single-spike) output. This decreased burst discharge of nRt neurons during CCK application reduced inhibitory drive onto VB neurons from multiple peaked inhibitory postsynaptic currents (IPSCs) to single peaked inhibitory events. We hypothesize that suppression of inhibitory drive onto VB neurons decreases their probability of burst output, which, together with a reduction of nRt burst output, dampens the oscillatory activity.Low CCK concentrations, which produced little or no depolarization of nRt neurons, did not alter the firing mode of the nRt neurons. However, the probability of burst output from nRt neurons in response to subthreshold stimuli was increased in low CCK concentrations, presumably leading to an increase in the number of nRt neurons participating in the rhythmic activity. Our findings suggest that the neuropeptide CCK, by altering the firing characteristics of nRt neurons, has powerful modulatory effects on intrathalamic rhythms; the ultimate action was dependent on CCK concentration and resting state of these cells.
Target-Specific Factors Regulate the Formation of Glutamatergic Transmitter Release Sites in Cultured Neocortical Neurons
Authors: Mohrmann Ralf , Werner Markus , Hatt Hanns , Gottmann Kurt 
Published: April 2018

Synapse formation in the mammalian CNS is thought to involve specific target recognition processes between presynaptic and postsynaptic neurons leading to the establishment of defined neuronal circuits. To study the role of target neuron-specific factors in synaptogenesis, we used cocultures of presynaptic explants and dissociated target neurons from rat neocortex, which enabled us to selectively vary the postsynaptic target neurons. Cocultures containing target neurons that were obtained early during development [embryonic day 16 (E16)] were compared to cocultures containing target neurons that were obtained at a later embryonic stage (E19).Postsynaptic currents (PSCs) were evoked in target neurons by maximal extracellular stimulation in the presynaptic explant. The mean amplitudes of AMPA and NMDA receptor-mediated PSCs were sixfold reduced in E16 target neurons, whereas the mean amplitudes of GABAAreceptor-mediated PSCs did not differ between E16 and E19 target neurons. This reduction was in part caused by an apparently twofold reduction in mean quantal amplitude, as shown by recording AMPA receptor-mediated miniature PSCs. In addition, a reduced number of glutamatergic release sites in E16 target neurons was revealed by synapsin I immunostaining of dendritic presynaptic terminals. No differences in mean release probability were observed between E16 and E19 target neurons.Thus, the formation of glutamatergic transmitter release sites was strongly influenced by target neuron-specific factors. The formation of functional GABAergic synapses, however, was independent of the type of target neurons, suggesting specific retrograde signaling during the establishment of glutamatergic synapses.
Attentional Orienting Is Impaired by Unilateral Lesions of the Thalamic Reticular Nucleus in the Rat
Authors: Weese G. Daniel , Phillips Janice M. , Brown Verity J. 
Published: April 2018

The thalamic reticular nucleus (TRN) has been implicated in attentional processes based on its anatomical, electrophysiological, and neurochemical relationships with the sensory nuclei of the thalamus and corresponding sensory areas of cortex. This study examined the possibility that the TRN is involved in covert orienting of attention. Attention can be summoned to a spatial location in the absence of an overt orienting response. The reaction time to a visual target is faster when attention has been drawn to the location of the target by a preceding cue in that location (valid cue) compared with when the cue misdirects attention (invalid cue) away from the location of the subsequent target. This reaction time difference is referred to as the “validity effect.”Rats were trained to perform such a reaction time task with visual cues and targets presented in poke holes to either side of the rat's head, which had to be maintained centrally and still. If the rat made an overt orienting response to the cue, the trial was aborted. Unilateral lesions were made by injection of ibotenic acid in the TRN. After surgery, there was no bias apparent in their responding; they were as likely to initiate responses and were equally accurate to either side. There was, however, a complete abolition of the validity effect for responses to contralateral targets. The data are discussed in terms of a role for the TRN in attentional processing.
Odors Elicit Three Different Oscillations in the Turtle Olfactory Bulb
Authors: Lam Ying-Wan , Cohen Lawrence B. , Wachowiak Matt , Zochowski Michal R. 
Published: April 2018

We measured the spatiotemporal aspects of the odor-induced population response in the turtle olfactory bulb using a voltage-sensitive dye, RH414, and a 464-element photodiode array. In contrast with previous studies of population activity using local field potential recordings, we distinguished four signals in the response. The one called DC covered almost the entire area of the olfactory bulb; in addition, three oscillations, named rostral, middle, and caudal according to their locations, occurred over broad regions of the bulb. In a typical odor-induced response, the DC signal appeared almost immediately after the start of the stimulus, followed by the middle oscillation, the rostral oscillation, and last, the caudal oscillation. The initial frequencies of the three oscillations were 14.1, 13.0, and 6.6 Hz, respectively. When the rostral and caudal oscillations occurred together, their frequencies differed by a factor of 1.99 ± 0.01.The following evidence suggests that the four signals are functionally independent: (1) in different animals some signals could be easily detected whereas others were undetectable; (2) the four signals had different latencies and frequencies; (3) the signals occurred in different locations and propagated in different directions; (4) the signals responded differently to changes in odor concentration; (5) the signals had different shapes; and (6) the rostral and caudal signals added in a simple, linear manner in regions where the location of the two signals overlapped. However, the finding that the frequency of the rostral oscillation is precisely two times that of the caudal oscillation suggests a significant relationship between the two.The location of the caudal oscillation in the bulb changed from cycle to cycle, implying that different groups of neurons are active in different cycles. This result is consistent with the earlier findings in the olfactory system of the locust (Wehr and Laurent, 1996).Our results suggest an additional complexity of parallel processing of olfactory input by multiple functional population domains.
A Site of Auditory Experience-Dependent Plasticity in the Neural Representation of Auditory Space in the Barn Owl's Inferior Colliculus
Authors: Gold Joshua I. , Knudsen Eric I. 
Published: April 2018

The barn owl's optic tectum contains a map of auditory space that is based, in part, on a map of interaural time difference (ITD). Previous studies have shown that this ITD map is shaped by auditory experience. In this study, we investigated whether the plasticity responsible for experience-induced changes in ITD tuning in the tectum occurs within the tectum itself or at an earlier stage in the auditory pathway.We altered auditory experience in young owls by implanting an acoustic filtering device in one ear that caused frequency-dependent changes in sound timing and level. We analyzed the representation of ITD in normal and device-reared owls in two nuclei in the ascending pathway: the external nucleus of the inferior colliculus (ICX), the primary source of ascending auditory input to the tectum, and the lateral shell of the central nucleus of the inferior colliculus (ICCls), the primary source of input to the ICX. In the ICX, device rearing caused adaptive, frequency-dependent changes in ITD tuning, as well as changes in frequency tuning. These changes in tuning were similar to changes that occurred in the optic tectum in the same owls. In contrast, in the ICCls, tuning for ITD and frequency was unaffected by device rearing. The data indicate that plasticity at the level of the ICX is largely responsible for the adaptive adjustments in ITD tuning and frequency tuning that are observed in the optic tecta of owls raised with abnormal auditory experience.
Postsynaptic Signaling via the μ-Opioid Receptor: Responses of Dorsal Horn Neurons to Exogenous Opioids and Noxious Stimulation
Authors: Trafton Jodie A. , Abbadie Catherine , Marek Kurt , Basbaum Allan I. 
Published: April 2018

Although both pre- and postsynaptic mechanisms have been implicated in the analgesia produced by μ-opioids at the spinal cord, it is not known under what conditions these different controls come into play. Because the μ-opioid receptor (MOR) can be visualized in individual lamina II excitatory interneurons and internalizes into endosomes on ligand binding, we tested whether MOR internalization could be monitored and used to measure postsynaptic MOR signaling. To test whether endogenous opioids modulate these lamina II interneurons during noxious stimulation, we next assessed the magnitude of postsynaptic MOR internalization under a variety of nociceptive conditions.As observed in other systems, we show that MOR internalization in dorsal horn interneurons is demonstrated readily in response to opioid ligands. The MOR internalization is dose-dependent, with a similar dose–response to that observed for opioid-induced increases in potassium conductance. We demonstrate that MOR internalization in lamina II neurons correlates precisely with the extent of analgesia produced by intrathecal DAMGO. These results suggest that MOR internalization provides a good marker of MOR signaling in the spinal cord and that postsynaptic MORs on lamina II interneurons likely participate in the analgesia that is produced by exogenous opioids. We found, however, that noxious stimuli, under normal or inflammatory conditions, did not induce MOR internalization. Thus, endogenous enkephalins and endomorphins, thought to be released during noxious peripheral stimuli, do not modulate nociceptive messages via postsynaptic MORs on lamina II interneurons. We suggest that any endogenous opioids that are released by noxious stimuli target presynaptic MORs or δ-opioid receptors.
Vitamin D Hormone Confers Neuroprotection in Parallel with Downregulation of L-Type Calcium Channel Expression in Hippocampal Neurons
Authors: Brewer Lawrence D. , Thibault Veronique , Chen Kuey-Chu , Langub Moises C. , Landfield Philip W. , Porter Nada M. 
Published: April 2018

Although vitamin D hormone (VDH; 1,25-dihydroxyvitamin D3), the active metabolite of vitamin D, is the major Ca2+-regulatory steroid hormone in the periphery, it is not known whether it also modulates Ca2+homeostasis in brain neurons. Recently, chronic treatment with VDH was reported to protect brain neurons in both aging and animal models of stroke. However, it is unclear whether those actions were attributable to direct effects on brain cells or indirect effects mediated via peripheral pathways. VDH modulates L-type voltage-sensitive Ca2+channels (L-VSCCs) in peripheral tissues, and an increase in L-VSCCs appears linked to both brain aging and neuronal vulnerability. Therefore, we tested the hypothesis that VDH has direct neuroprotective actions and, in parallel, targets L-VSCCs in hippocampal neurons.Primary rat hippocampal cultures, treated for several days with VDH, exhibited a U-shaped concentration–response curve for neuroprotection against excitotoxic insults: lower concentrations of VDH (1–100 nm) were protective, but higher, nonphysiological concentrations (500–1000 nm) were not. Parallel studies using patch-clamp techniques found a similar U-shaped curve in which L-VSCC current was reduced at lower VDH concentrations and increased at higher (500 nm) concentrations. Real-time PCR studies demonstrated that VDH monotonically downregulated mRNA expression for the α1Cand α1Dpore-forming subunits of L-VSCCs. However, 500 nmVDH also nonspecifically reduced a range of other mRNA species. Thus, these studies provide the first evidence of (1) direct neuroprotective actions of VDH at relatively low concentrations, and (2) selective downregulation of L-VSCC expression in brain neurons at the same, lower concentrations.
From Spectrum to Space: The Contribution of Level Difference Cues to Spatial Receptive Fields in the Barn Owl Inferior Colliculus
Authors: Euston David R. , Takahashi Terry T. 
Published: April 2018

Space-specific neurons in the owl's inferior colliculus have spatial receptive fields (RFs) computed from interaural time (ITD) and level (ILD) differences. Because of the shape of the owl's head, these cues vary with frequency in a manner specific for each location. We sought to determine the contribution of ILD to spatial selectivity. We measured the normal spatial receptive fields of space-specific neurons using virtual sound sources (i.e., noises filtered to simulate external sound sources, presented using headphones). The virtual-source filters were then altered so that ITD was fixed while frequency-specific ILDs varied according to location in the usual manner. The resulting “ILD-alone” RF typically revealed a horizontal band of excitation that included the normal RF. Above and below, the neurons were inhibited. Interestingly, the maxima of ILD-alone RFs were generally outside the normal RF, suggesting that space-specific neurons are not optimally tuned to the ILD spectrum occurring at the normal RF location. Congruously, frequency-specific ILD tuning, assessed with tones, better matched the ILDs at the peak of the ILD-alone RF than those at the peak of the normal RF. The firing evoked from the normal RF may thus reflect the balance of excitatory and inhibitory inputs needed to appropriately restrict the receptive field.Frequency-specific ILD tuning curves were combined with measured head-filtering characteristics to predict responses to the frequency-specific ILDs at each location. The predicted ILD-alone RFs, which are based on a simple sum of frequency-specific inputs, accounted for 56% of the variance in our measured ILD-alone RFs.
Isolation of a multipotent mesenchymal stem cell-like population from human adrenal cortex
Authors: Gan Earn H , Robson Wendy , Murphy Peter , Pickard Robert , Pearce Simon , Oldershaw Rachel 
Published: April 2018

Background
The highly plastic nature of adrenal cortex suggests the presence of adrenocortical stem cells (ACSC), but the exact in vivo identity of ACSC remains elusive. A few studies have demonstrated the differentiation of adipose or bone marrow-derived mesenchymal stem cells (MSC) into steroid-producing cells. We therefore investigated the isolation of multipotent MSC from human adrenal cortex.

Methods
Human adrenals were obtained as discarded surgical material. Single-cell suspensions from human adrenal cortex (n = 3) were cultured onto either complete growth medium (CM) or MSC growth promotion medium (MGPM) in hypoxic condition. Following ex vivo expansion, their multilineage differentiation capacity was evaluated. Phenotype markers were analysed by immunocytochemistry and flow cytometry for cell-surface antigens associated with bone marrow MSCs and adrenocortical-specific phenotype. Expression of mRNAs for pluripotency markers was assessed by q-PCR.

Results
The formation of colony-forming unit fibroblasts comprising adherent cells with fibroblast-like morphology were observed from the monolayer cell culture, in both CM and MGPM. Cells derived from MGPM revealed differentiation towards osteogenic and adipogenic cell lineages. These cells expressed cell-surface MSC markers (CD44, CD90, CD105 and CD166) but did not express the haematopoietic, lymphocytic or HLA-DR markers. Flow cytometry demonstrated significantly higher expression of GLI1 in cell population harvested from MGPM, which were highly proliferative. They also exhibited increased expression of the pluripotency markers.

Conclusion
Our study demonstrates that human adrenal cortex harbours a mesenchymal stem cell-like population. Understanding the cell biology of adrenal cortex- derived MSCs will inform regenerative medicine approaches in autoimmune Addison’s disease.
The Pseudokinase Domain of Saccharomyces cerevisiae Tra1 Is Required for Nuclear Localization and Incorporation into the SAGA and NuA4 Complexes
Authors: Berg Matthew D , Genereaux Julie , Karagiannis Jim , Brandl Christopher J 
Published: April 2018

Abstract
Tra1 is an essential component of the SAGA/SLIK and NuA4 complexes in S. cerevisiae, recruiting these co-activator complexes to specific promoters. As a PIKK family member, Tra1 is characterized by a C-terminal phosphoinositide 3-kinase (PI3K) domain. Unlike other PIKK family members (e.g., Tor1, Tor2, Mec1, Tel1), Tra1 has no demonstrable kinase activity. We identified three conserved arginine residues in Tra1 that reside proximal or within the cleft between the N- and C-terminal subdomains of the PI3K domain. To establish a function for Tra1’s PI3K domain and specifically the cleft region, we characterized a tra1 allele where these three arginine residues are mutated to glutamine. The half-life of the Tra1Q3 protein is reduced but its steady state level is maintained at near wild-type levels by a transcriptional feedback mechanism. The tra1Q3 allele results in slow growth under stress and alters the expression of genes also regulated by other components of the SAGA complex. Tra1Q3 is less efficiently transported to the nucleus than the wild-type protein. Likely related to this, Tra1Q3 associates poorly with SAGA/SLIK and NuA4. The ratio of Spt7SLIK to Spt7SAGA increases in the tra1Q3 strain and truncated forms of Spt20 become apparent upon isolation of SAGA/SLIK. Intragenic suppressor mutations of tra1Q3 map to the cleft region further emphasizing its importance. We propose that the PI3K domain of Tra1 is directly or indirectly important for incorporating Tra1 into SAGA and NuA4 and thus the biosynthesis and/or stability of the intact complexes.
Presentation with Personality changes and Tinnitus to a Vascular Intervention: Rare case of Carotid Body Paraganglioma
Authors: Zil-E-Ali Ahsan , Ahmed Zubair , Faquih Amber Ehsan , Ishaq Muhammad , Aadil Muhammad 
Published: April 2018

Background: Carotid body paragangliomas are rare neuroendocrine neoplasms of chromaffin negative glomus cells. This case report explains an atypical case with unusual presentation and treatment.
Case Report: A healthy smoker technician by profession was brought to the emergency room (ER) with coprolalia. The general physical exam did not reveal any information. His history revealed unilateral tinnitus and odynophagia leading to a consultation by the neurologist with head imaging. Acoustic neuroma was ruled out and the caregiver was asked to elaborate the events mentioned in the history and a psychiatric examination was done. The personality changes were evaluated by the psychiatrist that showed overlapping of delirium and depression. The patient was further examined by a vascular surgeon. After careful revisiting of the history, examination and indication of tender mass in the neck by the patient's vascular surgeon, the diagnosis of carotid body paraganglioma was made which was followed by surgical resection for treatment.
Conclusion: Carotid Body Paragangliomas are very vascular structures and their manipulation in a surgery setting requires expertise. This case presented with personality changes and tinnitus, a very less likely event to occur in a carotid body tumor. The present care report, thus adds on to the literature of carotid body tumors and its presenting symptoms.