175 research outputs found

    Galanin Receptor 1 Deletion Exacerbates Hippocampal Neuronal Loss after Systemic Kainate Administration in Mice

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    Galanin is a neuropeptide with a wide distribution in the central and peripheral nervous systems and whose physiological effects are mediated through three G protein-coupled receptor subtypes, GalR1, GalR2, and GalR3. Several lines of evidence indicate that galanin, as well as activation of the GalR1 receptor, is a potent and effective modulator of neuronal excitability in the hippocampus.In order to test more formally the potential influence of GalR1 on seizure-induced excitotoxic cell death, we conducted functional complementation tests in which transgenic mice that exhibit decreased expression of the GalR1 candidate mRNA underwent kainate-induced status epilepticus to determine if the quantitative trait of susceptibility to seizure-induced cell death is determined by the activity of GalR1. In the present study, we report that reduction of GalR1 mRNA via null mutation or injection of the GalR1 antagonist, galantide, prior to kainate-induced status epilepticus induces hippocampal damage in a mouse strain known to be highly resistant to kainate-induced neuronal injury. Wild-type and GalR1 knockout mice were subjected to systemic kainate administration. Seven days later, Nissl and NeuN immune- staining demonstrated that hippocampal cell death was significantly increased in GalR1 knockout strains and in animals injected with the GalR1 antagonist. Compared to GalR1-expressing mice, GalR1-deficient mice had significantly larger hippocampal lesions after status epilepticus.Our results suggest that a reduction of GalR1 expression in the C57BL/6J mouse strain renders them susceptible to excitotoxic injury following systemic kainate administration. From these results, GalR1 protein emerges as a new molecular target that may have a potential therapeutic value in modulating seizure-induced cell death

    Brains swinging in concert: cortical phase synchronization while playing guitar

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    <p>Abstract</p> <p>Background</p> <p>Brains interact with the world through actions that are implemented by sensory and motor processes. A substantial part of these interactions consists in synchronized goal-directed actions involving two or more individuals. Hyperscanning techniques for assessing fMRI simultaneously from two individuals have been developed. However, EEG recordings that permit the assessment of synchronized neuronal activities at much higher levels of temporal resolution have not yet been simultaneously assessed in multiple individuals and analyzed in the time-frequency domain. In this study, we simultaneously recorded EEG from the brains of each of eight pairs of guitarists playing a short melody together to explore the extent and the functional significance of synchronized cortical activity in the course of interpersonally coordinated actions.</p> <p>Results</p> <p>By applying synchronization algorithms to intra- and interbrain analyses, we found that phase synchronization both within and between brains increased significantly during the periods of (i) preparatory metronome tempo setting and (ii) coordinated play onset. Phase alignment extracted from within-brain dynamics was related to behavioral play onset asynchrony between guitarists.</p> <p>Conclusion</p> <p>Our findings show that interpersonally coordinated actions are preceded and accompanied by between-brain oscillatory couplings. Presumably, these couplings reflect similarities in the temporal properties of the individuals' percepts and actions. Whether between-brain oscillatory couplings play a causal role in initiating and maintaining interpersonal action coordination needs to be clarified by further research.</p

    Retinal Axonal Loss Begins Early in the Course of Multiple Sclerosis and Is Similar between Progressive Phenotypes

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    To determine whether retinal axonal loss is detectable in patients with a clinically isolated syndrome (CIS), a first clinical demyelinating attack suggestive of multiple sclerosis (MS), and examine patterns of retinal axonal loss across MS disease subtypes.Spectral-domain Optical Coherence Tomography was performed in 541 patients with MS, including 45 with high-risk CIS, 403 with relapsing-remitting (RR)MS, 60 with secondary-progressive (SP)MS and 33 with primary-progressive (PP)MS, and 53 unaffected controls. Differences in retinal nerve fiber layer (RNFL) thickness and macular volume were analyzed using multiple linear regression and associations with age and disease duration were examined in a cross-sectional analysis. In eyes without a clinical history of optic neuritis (designated as "eyes without optic neuritis"), the total and temporal peripapillary RNFL was thinner in CIS patients compared to controls (temporal RNFL by -5.4 µm [95% CI -0.9 to--9.9 µm, p = 0.02] adjusting for age and sex). The total (p = 0.01) and temporal (p = 0.03) RNFL was also thinner in CIS patients with clinical disease for less than 1 year compared to controls. In eyes without optic neuritis, total and temporal RNFL thickness was nearly identical between primary and secondary progressive MS, but total macular volume was slightly lower in the primary progressive group (p<0.05).Retinal axonal loss is increasingly prominent in more advanced stages of disease--progressive MS>RRMS>CIS--with proportionally greater thinning in eyes previously affected by clinically evident optic neuritis. Retinal axonal loss begins early in the course of MS. In the absence of clinically evident optic neuritis, RNFL thinning is nearly identical between progressive MS subtypes

    Aerosol delivery to ventilated newborn infants: historical challenges and new directions

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    There are several aerosolized drugs which have been used in the treatment of neonatal respiratory illnesses, such as bronchodilators, diuretics, and surfactants. Preclinical in vitro and in vivo studies identified a number of variables that affect aerosol efficiency, including particle size, aerosol flows, nebulizer choice, and placement. Nevertheless, an optimized aerosol drug delivery system for mechanically ventilated infants still does not exist. Increasing interest in this form of drug delivery requires more controlled and focused research of drug/device combinations appropriate for the neonatal population. In the present article, we review the research that has been conducted thus far and discuss the next steps in developing the optimal aerosol delivery system for use in mechanically ventilated neonates

    Long-Range Chromosome Organization in E. coli: A Site-Specific System Isolates the Ter Macrodomain

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    The organization of the Escherichia coli chromosome into a ring composed of four macrodomains and two less-structured regions influences the segregation of sister chromatids and the mobility of chromosomal DNA. The structuring of the terminus region (Ter) into a macrodomain relies on the interaction of the protein MatP with a 13-bp target called matS repeated 23 times in the 800-kb-long domain. Here, by using a new method that allows the transposition of any chromosomal segment at a defined position on the genetic map, we reveal a site-specific system that restricts to the Ter region a constraining process that reduces DNA mobility and delays loci segregation. Remarkably, the constraining process is regulated during the cell cycle and occurs only when the Ter MD is associated with the division machinery at mid-cell. The change of DNA properties does not rely on the presence of a trans-acting mechanism but rather involves a cis-effect acting at a long distance from the Ter region. Two specific 12-bp sequences located in the flanking Left and Right macrodomains and a newly identified protein designated YfbV conserved with MatP through evolution are required to impede the spreading of the constraining process to the rest of the chromosome. Our results unravel a site-specific system required to restrict to the Ter region the consequences of anchoring the Ter MD to the division machinery

    "Dreaming in colour’: disabled higher education students’ perspectives on improving design practices that would enable them to benefit from their use of technologies"

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    The focus of this paper is the design of technology products and services for disabled students in higher education. It analyses the perspectives of disabled students studying in the US, the UK, Germany, Israel and Canada, regarding their experiences of using technologies to support their learning. The students shared how the functionality of the technologies supported them to study and enabled them to achieve their academic potential. Despite these positive outcomes, the students also reported difficulties associated with: i) the design of the technologies, ii) a lack of technology know-how and iii) a lack of social capital. When identifying potential solutions to these difficulties the disabled students imagined both preferable and possible futures where faculty, higher education institutions, researchers and technology companies are challenged to push the boundaries of their current design practices

    Fundamentals of aerosol therapy in critical care

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    Genetic Diversity and Population Structure of Saccharomyces cerevisiae Strains Isolated from Different Grape Varieties and Winemaking Regions

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    We herein evaluate intraspecific genetic diversity of fermentative vineyard-associated S. cerevisiae strains and evaluate relationships between grape varieties and geographical location on populational structures. From the musts obtained from 288 grape samples, collected from two wine regions (16 vineyards, nine grape varieties), 94 spontaneous fermentations were concluded and 2820 yeast isolates were obtained that belonged mainly (92%) to the species S. cerevisiae. Isolates were classified in 321 strains by the use of ten microsatellite markers. A high strain diversity (8–43 strains per fermentation) was associated with high percentage (60–100%) of fermenting samples per vineyard, whereas a lower percentage of spontaneous fermentations (0–40%) corresponded to a rather low strain diversity (1–10 strains per fermentation)

    Widespread Hypomethylation Occurs Early and Synergizes with Gene Amplification during Esophageal Carcinogenesis

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    Although a combination of genomic and epigenetic alterations are implicated in the multistep transformation of normal squamous esophageal epithelium to Barrett esophagus, dysplasia, and adenocarcinoma, the combinatorial effect of these changes is unknown. By integrating genome-wide DNA methylation, copy number, and transcriptomic datasets obtained from endoscopic biopsies of neoplastic progression within the same individual, we are uniquely able to define the molecular events associated progression of Barrett esophagus. We find that the previously reported global hypomethylation phenomenon in cancer has its origins at the earliest stages of epithelial carcinogenesis. Promoter hypomethylation synergizes with gene amplification and leads to significant upregulation of a chr4q21 chemokine cluster and other transcripts during Barrett neoplasia. In contrast, gene-specific hypermethylation is observed at a restricted number of loci and, in combination with hemi-allelic deletions, leads to downregulatation of selected transcripts during multistep progression. We also observe that epigenetic regulation during epithelial carcinogenesis is not restricted to traditionally defined “CpG islands,” but may also occur through a mechanism of differential methylation outside of these regions. Finally, validation of novel upregulated targets (CXCL1 and 3, GATA6, and DMBT1) in a larger independent panel of samples confirms the utility of integrative analysis in cancer biomarker discovery
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