1,720,971 research outputs found
Natural Compounds as Beneficial Antioxidant Agents in Neurodegenerative Disorders: A Focus on Alzheimer’s Disease
Full text linkThe positive role of nutrition in chronic neurodegenerative diseases (NDs) suggests that dietary interventions represent helpful tools for preventing NDs. In particular, diets enriched with natural compounds have become an increasingly attractive, non-invasive, and inexpensive option to support a healthy brain and to potentially treat NDs. Bioactive compounds found in vegetables or microalgae possess special properties able to counteract oxidative stress, which is involved as a triggering factor in neurodegeneration. Here, we briefly review the relevant experimental data on curcuminoids, silymarin, chlorogenic acid, and compounds derived from the microalga Aphanizomenon flos aquae (AFA) which have been demonstrated to possess encouraging beneficial eects on neurodegeneration, in particular on Alzheimer’s disease models
TRPM8 channel activation reduces the spontaneous contractions in human distal colon
Full text linkThe transient receptor potential-melastatin 8 (TRPM8) is a non-selective Ca2+-permeable
channel, activated by cold, membrane depolarization, and different cooling compounds.
TRPM8 expression has been found in gut mucosal, submucosal, and muscular nerve endings.
Although TRPM8 plays a role in pathological conditions, being involved in visceral pain and
inflammation, the physiological functions in the digestive system remain unclear as yet. The aims of
the present study were: (i) to verify the TRPM8 expression in human distal colon; (ii) to examine
the effects of TRPM8 activation on colonic contractility; (iii) to characterize the mechanism of
action. Reverse transcriptase-polymerase chain reaction (RT-PCR) and western blotting were used
to analyze TRPM8 expression. The responses of human colon circular strips to different TRPM8
agonists [1-[Dialkyl-phosphinoyl]-alkane (DAPA) 2–5, 1-[Diisopropyl-phosphinoyl]-alkane (DIPA)
1–7, DIPA 1–8, DIPA 1–9, DIPA 1–10, and DIPA 1–12) were recorded using a vertical organ bath.
The biomolecular analysis revealed gene and protein expression of TRPM8 in both mucosal and
smooth muscle layers. All the agonists tested, except-DIPA 1–12, produced a concentration-dependent
decrease in spontaneous contraction amplitude. The effect was significantly antagonized by
5-benzyloxytryptamine, a TRPM8 antagonist. The DIPA 1–8 agonist resulted in the most efficacious
and potent activation among the tested molecules. The DIPA 1–8 effects were not affected by
tetrodotoxin, a neural blocker, but they were significantly reduced by tetraethylammonium chloride,
a non-selective blocker of K+ channels. Moreover, iberiotoxin, a blocker of the large-conductance
Ca2+-dependent K+-channels, but not apamin, a blocker of small-conductance Ca2+-dependent K+
channels, significantly reduced the inhibitory DIPA 1–8 actions. The results of the present study
demonstrated that TRPM8 receptors are also expressed in human distal colon in healthy conditions
and that ligand-dependent TRPM8 activation is able to reduce the colonic spontaneous motility,
probably by the opening of the large-conductance Ca2+-dependent K+-channels
Composizione comprendente indicaxantina per uso per la prevenzione e il trattamento del diabete mellito di tipo 2, obesità, stress ossidativo e patologie infiammatorie.
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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
A Natural Dietary Supplement with a Combination of Nutrients Prevents Neurodegeneration Induced by a High Fat Diet in Mice
Full text linkObesity and metabolic disorders can be risk factors for the onset and development of
neurodegenerative diseases. The aim of the present study was to investigate the protective effects of
a natural dietary supplement (NDS), containing Curcuma longa, silymarin, guggul, chlorogenic acid
and inulin, on dysmetabolism and neurodegeneration in the brains of high fat diet (HFD)-fed mice.
Decrease in the expression of FACL-4, CerS-1, CerS-4, cholesterol concentration and increase in the
insulin receptor expression and insulin signaling activation, were found in brains of NDS-treated
HFD brains in comparison with HFD untreated-mice, suggesting that NDS is able to prevent brain
lipid accumulation and central insulin resistance. In the brains of NDS-treated HFD mice, the levels
of RNS, ROS and lipid peroxidation, the expression of p-ERK, H-Oxy, i-NOS, HSP60, NF-kB, GFAP,
IL-1, IL-6 and CD4 positive cell infiltration were lower than in untreated HFD mice, suggesting
antioxidant and anti-inflammatory effects of NDS. The decreased expression of p-ERK and GFAP in
NDS-treated HFD mice was confirmed by immunofluorescence. Lastly, a lower number of apoptotic
nuclei was found in cortical sections of NDS-treated HFD mice. The present data indicate that NDS
exerts neuroprotective effects in HFD mice by reducing brain fat accumulation, oxidative stress and
inflammation and improving brain insulin resistance
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
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