1,721,149 research outputs found
Role of nociceptin/orphanin FQ in thermoregulation
No full textNociceptin/Orphanin FQ (N/OFQ) is a 17-amino acid peptide that binds to the nociceptin receptor (NOP). N/OFQ and NOP receptors are expressed in numerous brain areas. The generation of specific agonists, antagonists and receptor-deficient mice or rats has enabled progress in elucidating the biological functions of N/OFQ. These tools have been employed to identify the biological significance of the N/OFQ system and how it interacts with other endogenous systems to regulate several body functions. The present review focuses on the role of N/OFQ in the regulation of body temperature and its relationship with energy balance. Critical evaluation of the literature data suggests that N/OFQ, acting through the NOP receptor, may cause hypothermia by influencing the complex thermoregulatory system that operates as a federation of independent thermoeffector loops to control body temperature at the hypothalamic level. Furthermore, N/OFQ counteracts hyperthermia elicited by cannabinoids or μ-opioid agonists. N/OFQ-induced hypothermia is prevented by ω-conotoxin GVIA, an N-type calcium channel blocker. Hypothermia induced by N/OFQ is considered within the framework of the complex action that this neuropeptide exerts on energy balance. Energy stores are regulated through the complex neural controls exerted on both food intake and energy expenditure. In laboratory rodents, N/OFQ stimulates consummatory behavior and decreases energy expenditure. Taken together, these studies support the idea that N/OFQ contributes to the regulation of energy balance by acting as an “anabolic” neuropeptide as it elicits effects similar to those produced in the hypothalamus by other neuropeptides such as orexins and neuropeptide
Innovative opioid peptides and biased agonism: Novel avenues for more effective and safer analgesics to treat chronic pain
No full textBackground: Chronic pain states are clinically relevant and yet unsolved conditions impacting on quality of life and representing an important social and economic burden; these diseases are poorly treated with the currently available drugs, being urgent the need of innovative analgesics. In this frame, novel analogues of endomorphin-1 and dermorphin emerge as promising starting points to develop innovative, more effective analgesics to treat neuropathic pain. Methods: An extensive and structured search of bibliographic databases for peer-reviewed research literature was undertaken using focused review questions; all the retrieved papers were published on prestigious international journals by the experts of the field and were carefully analyzed to collect all the information and data necessary to the conceptual framework of this review. Results: One hundred papers were included in this review; forty-one defined the up-to-date findings on neuropathic pain etiopathogenesis and its currently available treatment options. Thirty-five papers described all the advantages and drawbacks of using endomorphin-1 (23) or dermorphin (12) in the frame of neuropathic pain and outlined the most relevant advances in developing endomorphin-1 and dermorphin analogs useful as potential, innovative analgesics. Twenty-four papers provided the latest insights into exploiting biased agonism at opioid receptor as an innovative strategy to develop more effective and safer analgesics. Conclusion: This review reports that innovative opioid peptides will be of great help in better understanding the multifaceted scenario of neuropathic pain treatment, providing very interesting opportunities for the identification of novel and more effective opioid analgesics to be employed as medications
Renilla luciferase reporter assay to study 3'UTR-driven posttranscriptional regulations of OPRM1.
No full textThe regulation of MOR expression at the level of mRNA is relevant for its role in pain transmission and in other functions involving opioid receptors. Recently, the role of the 3'UTR in the posttranscriptional regulation of MOR expression has been highlighted. Here we describe a Renilla luciferase reporter assay for the study of the effect of any selective treatment on the 3'UTR-dependent regulation of OPRM1 in a model of glial cells
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Targeting α4β1 integrin: from cyclic to linear ligands, effects of chemical modifications
No full textThe immune system depends on integrins for adhesion and migration during leukocyte trafficking and for intracellular signalling. There is a causal relationship between dysregulation of integrin expression and the onset of pathological conditions, such as autoimmune diseases, inflammation, cancer, and infections. Therefore, integrins, such as α4β1, are considered important therapeutic targets. In this study, a series of novel compounds were synthesized and evaluated for affinity and potency towards α4β1, and selectivity towards α5β1, and αMβ2 integrins. Three compounds 3, 4, and 8 showed excellent binding affinities (Ki < 10 nM) for α4β1. In cell adhesion assays these three ligands behaved as antagonists of α4β1, as confirmed by integrin-mediated intracellular signalling with a functional selectivity over ERK1/2 signalling pathway. Notably, compound 4, a proline derivative, was an antagonist against α4β1 (IC50 15 ± 3 nM) and an agonist against αMβ2 integrin (EC50 23 ± 5 nM). Compound 2, a fluorinated β-lactam derivative, was a selective and potent agonist of α5β1 (EC50 45.98 ± 7.92 nM). Compound 5, although it seems to bind to a different site compared to LDV in α4β1 integrin, showed an agonist behaviour in cell adhesion mediated by α4β1 and α5β1 integrin (EC50 25 ± 3 and 4.8 ± 3.4 nM, respectively) and in activating α4β1 integrin-mediated ERK1/2 and Akt phosphorylation. Compound 8 was the most potent agonist of the series against αMβ2 (EC50 1.4 ± 0.2 nM). Overall, the present study provides new insights into the effects of new integrin ligands that could be considered as potential lead compounds for therapeutic applications in inflammatory diseases and cancer
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