124 research outputs found
Microbiome-gut-brain axis and toll-like receptors in parkinson\u2019s disease
Parkinson’s disease (PD) is a progressively debilitating neurodegenerative disease characterized by α-synucleinopathy, which involves all districts of the brain-gut axis, including the central, autonomic and enteric nervous systems. The highly bidirectional communication between the brain and the gut is markedly influenced by the microbiome through integrated immunological, neuroendocrine and neurological processes. The gut microbiota and its relevant metabolites interact with the host via a series of biochemical and functional inputs, thereby affecting host homeostasis and health. Indeed, a dysregulated microbiota-gut-brain axis in PD might lie at the basis of gastrointestinal dysfunctions which predominantly emerge many years prior to the diagnosis, corroborating the theory that the pathological process is spread from the gut to the brain. Toll-like receptors (TLRs) play a crucial role in innate immunity by recognizing conserved motifs primarily found in microorganisms and a dysregulation in their signaling may be implicated in α-synucleinopathy, such as PD. An overstimulation of the innate immune system due to gut dysbiosis and/or small intestinal bacterial overgrowth, together with higher intestinal barrier permeability, may provoke local and systemic inflammation as well as enteric neuroglial activation, ultimately triggering the development of alpha-synuclein pathology. In this review, we provide the current knowledge regarding the relationship between the microbiota-gut–brain axis and TLRs in PD. A better understanding of the dialogue sustained by the microbiota-gut-brain axis and innate immunity via TLR signaling should bring interesting insights in the pathophysiology of PD and provide novel dietary and/or therapeutic measures aimed at shaping the gut microbiota composition, improving the intestinal epithelial barrier function and balancing the innate immune response in PD patients, in order to influence the early phases of the following neurodegenerative cascade
Experiences on Using Intelligent Planning for Curriculum Personalization in Moodle
In this paper we discuss our experiences on using artificial intelligence to plan customized learning
paths in the Moodle platform. In particular, we found some limitations in defining students’ profiles,
complex relationships between activities and personalized views of the learning contents. We show
how we solved this kind of problems in order to create an integrated system for the application of our
planning approach in MoodleValentina Caputi thanks the European Commission, the European Social Fund, and the Regione
Calabria for financial support of her PhD fellowship and funding for her stay in Valencia.
This paper is co-funded with support from the European Commission, the European Social Fund and
the Regione Calabria. The paper was also partially funded by the Consolider AT project CSD2007-
0022 INGENIO 2010 of the Spanish Ministry of Science and Innovation, the MICINN project TIN2011-
27652-C03-01 and the Valencian Prometeo project 2008/051. The European Commission and the Regione Calabria disclaim any responsibility for the use that may
be made of the information contained in this publicationCaputi, V.; Garrido Tejero, A. (2013). Experiences on Using Intelligent Planning for Curriculum Personalization in Moodle. En EDULEARN13 Proceedings. IATED. 168-176. http://hdl.handle.net/10251/71817S16817
Functional and molecular alterations of the enteric nervous system in murine models of gut neuropathy
The interaction between cellular constituents of gastrointestinal (GI) tract and commensal microflora is essential for the maintenance of mucosal barrier, promotion of the development of the GI system and modulation of enteric functions such as motility, secretion, mucosal immunity and visceral sensitivity. Alterations in the composition of the gut microflora have been associated to several GI disorders (e.g. inflammatory bowel disease, IBD, and irritable bowel syndrome, IBS) while changes in intestinal microbiota during infancy and adolescence, caused by infection or antibiotic therapy, appear to predispose to the onset of these diseases. Furthermore, dysfunctions of the enteric nervous system (ENS) such structural abnormalities and/or changes in the content of neurotransmitters, have been associated with the onset of IBD and IBS. In this context, a sophisticated system of proteins, so-called Toll-like receptors (TLRs), plays a key role in mediating the inflammatory response against pathogens and triggers beneficial signals to ensure tissue integrity under physiological and pathological conditions. Polymorphisms in genes encoding TLRs, including TLR2 or TLR4, have been associated with different phenotypes of disease extent and severity in patients with GI disorders. In this study we characterized structural and functional alterations of murine ENS induced by: i) anomalies in the composition of the microbiota, ii) changes in innate immunity response, mediated by TLR2 and/or TLR4 following recognition of gut commensal microflora, iii) alterations in the expression of the protein catechol-O-methyltransferase (COMT), involved in the turnover of several neurotransmitters present in both the ENS and the central nervous system, such as dopamine and other catecholamines. Functional and structural studies in male mice C57BL/6J WT and TLR2-/- (21 ± 5 days old) highlighted the presence of significant alterations of intestinal contractility and ENS architecture in ileal preparations of genetically modified mice. Once demonstrated that the deletion of the gene encoding for TLR2 determines ENS structural and functional abnormalities, it was examined whether TLR2-mediated functional anomalies were hematopoietic cell-independent. Therefore, bone marrow chimeric mice were generated and experimental transfers were as follows: WT donors into WT recipients (WT?WT), WT donors into TLR2-/- recipients (WT? TLR2-/-), TLR2-/- donors into TLR2-/- recipients (TLR2-/-? TLR2-/-), and TLR2-/- donors into WT recipients (TLR2-/-? WT). Contractility experiments conducted in bone marrow chimeric mice evidenced that the structure and function of ENS were similar in WT mice given either WT or TLR2?/? bone marrow, indicating that TLR2 signaling in nonhematopoietic cells is a main contributor to ENS health. To investigate the role of the TLR2-microbiota axis in the homeostasis of ENS and enteric smooth muscle we depleted gut microbiota by intragastric administration of a cocktail of broad spectrum antibiotics (50 mg/kg vancomycin, 100 mg/kg neomycin, 100 mg/kg metronidazol and 100 mg/kg ampicillin) twice a day for 14 days in adolescent mice (aged 21 ± 5, ABX). Mice resulted to be successfully depleted after antibiotic treatment and displayed significantly smaller spleens and enlarged ceca, macroscopically phenocopying germ-free mice. This condition, already highlighted in IBS subjects, appears to be due to a delayed emptying of feces from enlarged cecum, due to impaired motility. Functional studies in ABX mice revealed a significant decrease in gastrointestinal transit, accompanied by alterations in the rate of fecal pellet expulsion and stool water content, to suggest that continuous presence of microbial stimuli is required to control intestinal motility and potentially mucosal barrier permeability. Immunohistochemical analysis of ileal preparations from ABX mice showed abnormalities in the distribution and expression of the the pan-neuronal marker HuC/D, the glial structural protein GFAP (glial fibrillary acidic protein) and the cytoplasmatic and nuclear glial calcium-binding protein S100?. Overall these observations highlight the primary role of commensal microbiota in the preservation of the structural integrity of the enteric neuronal and glial network. Given the importance of proper composition of commensal microbiota in the maintenance of neuronal network and neurochemical coding of the ENS intestinal contractility was evaluated in isolated ileal segments from control and ABX mice. These analyses evidenced impaired neuromuscular function associated to antibiotic treatment to further underline that proper neuromuscular function relies on a correct composition of gut microbiota.
The primary role of TLR2 signaling in controlling gut motor function was further confirmed by testing the effect of TLR2 engagement by Pam3-CSK4 (a TLR2/TLR1 agonist) in ABX mice. Intraperitoneal supplementation with Pam3CSK4, during the second week of antibiotic treatment, partially corrected these anomalies in ENS structure and intestinal contraction, supporting the presence of a dialogue between commensal microbiota and TLR2, essential for the modulation of neuromuscular function. To highlight the key role of gut microbiota?TLR2-ENS axis in maintaining intestinal function and development of the ENS, male C57Bl/6 mice (2 weeks old) were daily treated subcutaneously with OxPAPC (a TLR2 and TLR4 inhibitor) for 7 days. In vivo inhibition of both TLR2 and TLR4 determined a significant alteration of receptor and non-receptor-mediated neuromuscular responses, in a manner similar to that found in TLR2-deficient mice, providing evidence that TLR2 and TLR4 signaling is essential in ensuring the structural and functional integrity of the SNE during adolescence. Then, we investigate changes in gene expression of GluN1 subunit of N-Methyl-D-Aspartate (NMDA) receptor of the neurotransmitter glutamate in the myenteric plexus of ileal preparations from control and ABX mice. Antibiotic-mediated depletion of commensal microflora determined increased mRNA levels of GluN1, suggesting that commensal microbiota is involved in modulating visceral sensitivity.
Finally, the role of brain-gut axis in ENS homeostasis was assessed in an animal model of psychiatric disease, characterized by the genetic reduction of catechol-o-methyltransferase (COMT), an enzyme responsible for the degradation of catecholamines. In female animals genetic-driven COMT defective activity determined increased levels of NO associated to altered ENS architecture, neurochemical coding and visceral sensitivity. We cannot exclude that such changes may be involved in the pathogenesis of IBS in female patients, underlining a potential link with psychiatric disorders
The influence of emotional picture thematic content on exploratory eye movements
In picture viewing, emotional vs. neutral stimuli could play a different role in eye movement parameters and in the spatial progression of the scanpath. The aim of this paper is to investigate exploratory behaviour of normal subjects during the vision of emotional vs. non-emotional stimuli, by considering to what extent the thematic content (animate vs. inanimate) is likely to influence the observer’s eye movements. Sixty-five subjects’ eye movement patterns were measured while looking to emotional (pleasant and unpleasant) and neutral pictures depicting animate or inanimate contents. Results showed that the number of fixations and the gaze duration were greater for emotional pictures than for neutral ones, and animate pictures were fixated longer than inanimate ones. Both emotional and animate pictures may affect eye movements and constitute privileged stimuli of adaptive behavioural tendencies
Saccharomyces boulardii CNCM I-745 supplementation reduces gastrointestinal dysfunction in an animal model of IBS
We evaluated the effect of Saccharomyces boulardii CNCM I-745 on intestinal neuromuscular anomalies in an IBS-type mouse model of gastrointestinal motor dysfunctions elicited by Herpes Simplex Virus type 1 (HSV-1) exposure.Mice were inoculated intranasally with HSV-1 (102 PFU) or vehicle at time 0 and 4 weeks later by the intragastric (IG) route (108 PFU). Six weeks after IG inoculum, mice were randomly allocated to receive oral gavage with either S. boulardii (107 CFU/day) or vehicle. After 4 weeks the following were determined: a) intestinal motility using fluorescein-isothiocyanate dextran distribution in the gut, fecal pellet expulsion, stool water content, and distal colonic transit of glass beads; b) integrity of the enteric nervous system (ENS) by immunohistochemistry on ileal whole-mount preparations and western blot of protein lysates from ileal longitudinal muscle and myenteric plexus; c) isometric muscle tension with electric field and pharmacological (carbachol) stimulation of ileal segments; and d) intestinal inflammation by levels of tumor necrosis factor α, interleukin(IL)-1β, IL-10 and IL-4.S. boulardii CNCM I-745 improved HSV-1 induced intestinal dysmotility and alteration of intestinal transit observed ten weeks after IG inoculum of the virus. Also, the probiotic yeast ameliorated the structural alterations of the ENS induced by HSV-1 (i.e., reduced peripherin immunoreactivity and expression, increased glial S100β protein immunoreactivity and neuronal nitric oxide synthase level, reduced substance P-positive fibers). Moreover, S. boulardii CNCM I-745 diminished the production of HSV-1 associated pro-inflammatory cytokines in the myenteric plexus and increased levels of anti-inflammatory interleukins.S. boulardii CNCM I-745 ameliorated gastrointestinal neuromuscular anomalies in a mouse model of gut dysfunctions typically observed with irritable bowel syndrome
Toll-Like Receptor 4 Modulates Small Intestine Neuromuscular Function through Nitrergic and Purinergic Pathways
Objective: Toll-like receptors (TLRs) play a pivotal role in the homeostatic microflora-host crosstalk. TLR4-mediated modulation of both motility and enteric neuronal survival has been reported mainly for colon with limited information on the role of TLR4 in tuning structural and functional integrity of enteric nervous system (ENS) and in controlling small bowel motility.
Methods: Male TLR4 knockout (TLR4-/-, 9 \ub1 1 weeks old) and sex- and age-matched wild-type (WT) C57BL/6J mice were used for the experiments. Alterations in ENS morphology and neurochemical code were assessed by immunohistochemistry whereas neuromuscular function was evaluated by isometric mechanical activity of ileal preparations following receptor and non-receptor-mediated stimuli and by gastrointestinal transit.
Results: The absence of TLR4 induced gliosis and reduced the total number of neurons, mainly nNOS+ neurons, in ileal myenteric plexus. Furthermore, a lower cholinergic excitatory response with an increased inhibitory neurotransmission was found together with a delayed gastrointestinal transit. These changes were dependent on increased ileal non-adrenergic non-cholinergic (NANC) relaxations mediated by a complex neuronal-glia signaling constituted by P2X7 and P2Y1 receptors, and NO produced by nNOS and iNOS.
Conclusion: We provide novel evidence that TLR4 signaling is involved in the fine-tuning of P2 receptors controlling ileal contractility, ENS cell distribution, and inhibitory NANC neurotransmission via the combined action of NO and adenosine-5\u2032-triphosphate (ATP). For the first time, this study implicates TLR4 at regulating the crosstalk between glia and neurons in small intestine and helps to define its role in gastrointestinal motor abnormalities during dysbiosis
Depression and cardiovascular disease: The deep blue sea of women's heart
Abstract Cardiovascular disease (CVD) constitutes a leading worldwide health problem, with increasing evidence of differences between women and men both in epidemiology, pathophysiology, clinical management, and outcomes. Data from the literature suggest that women experience a doubled incidence of CVD related deaths, while angina, heart failure and stroke are increasingly prevalent in females. About 20–25% of women go through depression during their life, and depressive symptoms have been considered a relevant emergent, non-traditional risk factor for CVD in this part of the general population. Underlying mechanisms explaining the link between depression and CVD may range from behavioral to biological risk factors, including sympathetic nervous system hyperactivity and impairment in hypothalamic-pituitary-adrenal function. However, the neuroendocrine-driven background could only partially explain the differences mentioned above for chronic systemic inflammation, altered hemostasis and modulation of cardiac autonomic control. In addition, some evidence also suggests the existence of gender-specific differences in biological responses to mental stress. Given these premises, we here summarize the current knowledge about depression and CVD relationship in women, highlighting the sex differences in physiopathology, clinical presentation and treatments
Genomic and comparative analysis of the T cell receptor gamma locus in two Equus species
The genus Equus is the only extant genus of the Equidae family, which belongs to Perissodactyla, an order of mammals characterized by an odd number of toes (odd-toes ungulates). Taking advantage of the latest release of the genome assembly, we studied, for the first time in two organisms belonging to the Equus genus, the horse (Equus caballus) and the donkey (Equus asinus), the T cell receptor gamma (TRG) locus encoding the gamma chain of the γδ T cell receptor. Forty-five Variable (TRGV) genes belonging to the seven IMGT-NC validated mammalian TRGV subgroups, 25 Joining (TRGJ) and 17 Constant (TRGC) genes organized in 17 V-J-(J)-C cassettes, in tandem on about 1100 Kb, characterize the horse TRG locus, making the horse TRG locus the one with the greatest extension and with a significantly higher number of genes than the orthologous loci of the other mammalian species. A clonotype analysis of an RNA-seq transcriptomic dataset derived from spleen of an adult healthy horse, using the complete set of the horse TRGJ germline gene sequences as a probe, revealed that, in addition to the most prominent V-J rearrangements within each cassette, there is a relevant proportion of trans-cassette V-J recombination, whereby the same TRGV genes can recombine with different TRGJ genes spliced to the corresponding TRGC genes. This recombinant event strongly contributes to the diversity of the γ chain repertoire. In the donkey TRG locus, 34 TRGV, 21 TRGJ and 14 TRGC genes distributed in 14 V-J-(J)-C cassettes were found in a region of approximately 860 kb. Although the donkey’s TRG is smaller than that of the horse, in Equus genus, this is still the second largest locus so far found in any mammalian species. Finally, the comparative analysis highlighted differences in size and gene content between the horse and donkey TRG loci, despite belonging to the same genus, indicating a good level of diversification within Equus. These data is in agreement with the evolutionary idea of the existence of a Equus recent common ancestor in rapid evolution, for which a mutation rate between horses and donkeys is more comparable to that between species belonging to different genera rather than to species of the same genus
Student-oriented planning of e-learning contents for Moodle
We present a way to automatically plan student-oriented learning contents in Moodle. Rather than
offering the same contents for all students, we provide personalized contents according to the students'
background and learning objectives. Although curriculum personalization can be faced in several ways,
we focus on artificial intelligence (AI) planning as a very useful formalism for mapping actions, i.e.
learning contents, in terms of preconditions (precedence relationships) and causal effects to find plans,
i.e. learning paths that best fit the needs of each student. A key feature is that the learning path is
generated and shown in Moodle in a seamless way for both the teacher and student, respectively. We
also include some experimental results to demonstrate the scalability and viability of our approach.
& 2015 Elsevier Ltd. All rights reservedThis paper is co-funded with support from the European Commission, the European Social Fund and the Regione Calabria. The paper was also partially funded by the Consolider AT project CSD2007-0022 INGENIO 2010 of the Spanish Ministry of Science and Innovation, the MICINN project TIN2011-27652-C03-01 and the Valencian Prometeo project II/2013/019.Caputi, V.; Garrido Tejero, A. (2015). Student-oriented planning of e-learning contents for Moodle. Journal of Network and Computer Applications. 53:115-127. https://doi.org/10.1016/j.jnca.2015.04.001S1151275
Comparative Effectiveness of Biosimilar, Reference Product and Other Erythropoiesis-Stimulating Agents (ESAs) Still Covered by Patent in Chronic Kidney Disease and Cancer Patients: An Italian Population-Based Study
Background Since 2007 biosimilars of erythropoiesis-stimulating agents (ESAs) are available on the Italian market. Very limited post-marketing data exist on the comparative effectiveness of biosimilar and originator ESAs. Aim This population-based study was aimed to compare the effects of biosimilars, reference product and other ESAs still covered by patent on hemoglobinemia in chronic kidney disease (CKD) and cancer patients in a Local Health Unit (LHU) from Northern Italy. Methods A retrospective cohort study was conducted during the years 2009-2014 using data from Treviso LHU administrative database. Incident ESA users (no ESA dispensing within 6 months prior to treatment start, i.e. index date (ID)) with at least one hemoglobin measurement within one month prior to ID (baseline Hb value) and another measurement between 2nd and 3rd month after ID (follow-up Hb value) were identified. The strength of the consumption (as total number of defined daily dose (DDD) dispensed during the follow-up divided by days of follow-up) and the difference between follow-up and baseline Hb values [delta Hb (ΔHb)] were evaluated. Based on Hb changes, ESA users were classified as non-responders (ΔHb≤0 g/dl), responders (0Delta;Hb≤2 g/dl), and highly responders (ΔHb>2 g/ dl). A multivariate ordinal logistic regression model to identify predictors for responsiveness to treatment was performed. All analyses were stratified by indication for use and type of dispensed ESA at ID. Results Overall, 1,003 incident ESA users (reference product: 252, 25.1%; other ESAs covered by patent: 303, 30.2%; biosimilars: 448, 44.7%) with CKD or cancer were eligible for the study. No statistically significant difference in the amount of dose dispensed during the follow-up among biosimilars, reference product and other ESAs covered by patent was found in both CKD and cancer. After three months from treatment start, all ESAs increased Hb values on average by 2g/dl. No differences in ΔHb as well as in frequency of non-responders, responders and highly responders among different types of ESAs were observed in both indications of use. Overall, around 15-20% of ESA users were non-responders. Strength of treatment, but no type of dispensed ESAs was found to be predictor of responsiveness to treatment. Conclusions No difference on the effects on hemoglobinemia among users of either biosimilars or reference product or ESAs covered by patent was observed in a general population from Northern Italy, despite a comparable dispensed dose of the different ESAs during the first three months of treatment
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