884 research outputs found

    Vibrational analysis of d-PCL(530)/siloxane based hybrids doped with two lithium salts

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    Published online: 22 May 2013The present study has been focused on environmentally friendly sol-gel derived electrolytes based on a di-urethane cross-linked d-PCL(530)/siloxane network (where d represents di, PCL identifies the poly(ε–caprolactone) biopolymer and 530 is the average molecular weight in g.mol-1) doped with a wide range of concentration of lithium perchlorate (LiClO4) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). Fourier Transform Infrared and Raman (FT-IR and FT-Raman, respectively) spectroscopies have been applied to evaluate the extent of ionic association. Characteristic bands of the PCL(530) segments, of the urethane cross-links and of the anions have been examined to gain insight into the cation/biopolymer, cation/anion and cation/cross-link interactions. In both electrolyte systems “free” ions and contact ions have been identified. The addition of salt modifies the hydrogen-bonded array of the host matrix, causing the destruction/formation of the urethane/urethane aggregates.Fundação para a Ciência e a Tecnologia (FCT

    Safety and immunomodulatory effects of three probiotic strains isolated from the feces of breast-fed infants in healthy adults: SETOPROB study

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    We previously described the isolation and characterization of three probiotic strains from the feces of exclusively breast-fed newborn infants: Lactobacillus paracasei CNCM I-4034, Bifidobacterium breve CNCM I-4035 and Lactobacillus rhamnosus CNCM I-4036. These strains were shown to adhere to intestinal mucus in vitro, to be sensitive to antibiotics and to resist biliary salts and low pH. In the present study, a multicenter, randomized, double-blind, placebo-controlled trial with 100 healthy volunteers in three Spanish cities was carried out to evaluate the tolerance, safety, gut colonization and immunomodulatory effects of these three probiotics. Volunteers underwent a 15-day washout period, after which they were randomly divided into 5 groups that received daily a placebo, a capsule containing one of the 3 strains or a capsule containing a mixture of two strains for 30 days. The intervention was followed by another 15-day washout period. Patients did not consume fermented milk for the entire duration of the study. Gastrointestinal symptoms, defecation frequency and stool consistency were not altered by probiotic intake. No relevant changes in blood and serum, as well as no adverse events occurred during or after treatment. Probiotic administration slightly modified bacterial populations in the volunteers’ feces. Intestinal persistence occurred in volunteers who received L. rhamnosus CNCM I-4036. Administration of B. breve CNCM I-4035 resulted in a significant increase in fecal secretory IgA content. IL-4 and IL-10 increased, whereas IL-12 decreased in the serum of volunteers treated with any of the three strains. These results demonstrate that the consumption of these three bacterial strains was safe and exerted varying degrees of immunomodulatory effects.Part of the research currently in progress in the authors' laboratory is funded by the company Hero Spain, S. A. through the grant #3582 managed by the Fundacion General Empresa-Universidad de Granada

    Inadequate control of thyroid hormones sensitizes to hepatocarcinogenesis and unhealthy aging

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    An inverse correlation between thyroid hormone levels and longevity has been reported in several species and reduced thyroid hormone levels have been proposed as a biomarker for healthy aging and metabolic fitness. However, hypothyroidism is a medical condition associated with compromised health and reduced life expectancy. Herein, we show, using wild-type and the Pax8 ablated model of hypothyroidism in mice, that hyperthyroidism and severe hypothyroidism are associated with an overall unhealthy status and shorter lifespan. Mild hypothyroid Pax8 +/- mice were heavier and displayed insulin resistance, hepatic steatosis and increased prevalence of liver cancer yet had normal lifespan. These pathophysiological conditions were precipitated by hepatic mitochondrial dysfunction and oxidative damage accumulation. These findings indicate that individuals carrying mutations on PAX8 may be susceptible to develop liver cancer and/or diabetes and raise concerns regarding the development of interventions aiming to modulate thyroid hormones to promote healthy aging or lifespan in mammals

    Ghrelin Modulates the fMRI BOLD Response of Homeostatic and Hedonic Brain Centers Regulating Energy Balance in the Rat

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    The orexigenic gut-brain peptide, ghrelin and its G-protein coupled receptor, the growth hormone secretagogue receptor 1a (GHS-R1A) are pivotal regulators of hypothalamic feeding centers and reward processing neuronal circuits of the brain. These systems operate in a cooperative manner and receive a wide array of neuronal hormone/transmitter messages and metabolic signals. Functional magnetic resonance imaging was employed in the current study to map BOLD responses to ghrelin in different brain regions with special reference on homeostatic and hedonic regulatory centers of energy balance. Experimental groups involved male, ovariectomized female and ovariectomized estradiol-replaced rats. Putative modulation of ghrelin signaling by endocannabinoids was also studied. Ghrelin-evoked effects were calculated as mean of the BOLD responses 30 minutes after administration. In the male rat, ghrelin evoked a slowly decreasing BOLD response in all studied regions of interest (ROI) within the limbic system. This effect was antagonized by pretreatment with GHS-R1A antagonist JMV2959. The comparison of ghrelin effects in the presence or absence of JMV2959 in individual ROIs revealed significant changes in the prefrontal cortex, nucleus accumbens of the telencephalon, and also within hypothalamic centers like the lateral hypothalamus, ventromedial nucleus, paraventricular nucleus and suprachiasmatic nucleus. In the female rat, the ghrelin effects were almost identical to those observed in males. Ovariectomy and chronic estradiol replacement had no effect on the BOLD response. Inhibition of the endocannabinoid signaling by rimonabant significantly attenuated the response of the nucleus accumbens and septum. In summary, ghrelin can modulate hypothalamic and mesolimbic structures controlling energy balance in both sexes. The endocannabinoid signaling system contributes to the manifestation of ghrelin’s BOLD effect in a region specific manner. In females, the estradiol milieu does not influence the BOLD response to ghrelin

    Classical Simulation of Relativistic Quantum Mechanics in Periodic Optical Structures

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    Spatial and/or temporal propagation of light waves in periodic optical structures offers a rather unique possibility to realize in a purely classical setting the optical analogues of a wide variety of quantum phenomena rooted in relativistic wave equations. In this work a brief overview of a few optical analogues of relativistic quantum phenomena, based on either spatial light transport in engineered photonic lattices or on temporal pulse propagation in Bragg grating structures, is presented. Examples include spatial and temporal photonic analogues of the Zitterbewegung of a relativistic electron, Klein tunneling, vacuum decay and pair-production, the Dirac oscillator, the relativistic Kronig-Penney model, and optical realizations of non-Hermitian extensions of relativistic wave equations.Comment: review article (invited), 14 pages, 7 figures, 105 reference

    Current and Future Drug Targets in Weight Management

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    Obesity will continue to be one of the leading causes of chronic disease unless the ongoing rise in the prevalence of this condition is reversed. Accumulating morbidity figures and a shortage of effective drugs have generated substantial research activity with several molecular targets being investigated. However, pharmacological modulation of body weight is extremely complex, since it is essentially a battle against one of the strongest human instincts and highly efficient mechanisms of energy uptake and storage. This review provides an overview of the different molecular strategies intended to lower body weight or adipose tissue mass. Weight-loss drugs in development include molecules intended to reduce the absorption of lipids from the GI tract, various ways to limit food intake, and compounds that increase energy expenditure or reduce adipose tissue size. A number of new preparations, including combinations of the existing drugs topiramate plus phentermine, bupropion plus naltrexone, and the selective 5-HT2C agonist lorcaserin have recently been filed for approval. Behind these leading candidates are several other potentially promising compounds and combinations currently undergoing phase II and III testing. Some interesting targets further on the horizon are also discussed

    Association of a single nucleotide polymorphism combination pattern of the Klotho gene with non-cardiovascular death in patients with chronic kidney disease

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    Chronic kidney disease (CKD) is associated with an elevated risk of all-cause mortality, with cardiovascular death being extensively investigated. However, non-cardiovascular mortality represents the biggest percentage, showing an evident increase in recent years. Klotho is a gene highly expressed in the kidney, with a clear influence on lifespan. Low levels of Klotho have been linked to CKD progression and adverse outcomes. Single nucleotide polymorphisms (SNPs) of the Klotho gene have been associated with several diseases, but studies investigating the association of Klotho SNPs with noncardiovascular death in CKD populations are lacking. The main aim of this study was to assess whether 11 Klotho SNPs were associated with non-cardiovascular death in a subpopulation of the National Observatory of Atherosclerosis in Nephrology (NEFRONA) study (n ¼ 2185 CKD patients). After 48 months of follow-up, 62 cardiovascular deaths and 108 non-cardiovascular deaths were recorded. We identified a high non-cardiovascular death risk combination of SNPs corresponding to individuals carrying the most frequent allele (G) at rs562020, the rare allele (C) at rs2283368 and homozygotes for the rare allele (G) at rs2320762 (rs562020 GG/AG þ rs2283368 CC/CT þ rs2320762 GG). Among the patients with the three SNPs genotyped (n ¼ 1016), 75 (7.4%) showed this combination. Furthermore, 95 (9.3%) patients showed a low-risk combination carrying all the opposite genotypes (rs562020 AA þ rs2283368 TT þ rs2320762 GT/TT). All the other combinations [n ¼ 846 (83.3%)] were considered as normal risk. Using competing risk regression analysis, we confirmed that the proposed combinations are independently associated with a higher fhazard ratio [HR] 3.28 [confidence interval (CI) 1.51-7.12]g and lower [HR 6 × 10- (95% CI 3.3 × 10--1.1 × 10-)] risk of suffering a non-cardiovascular death in the CKD population of the NEFRONA cohort compared with patients with the normal-risk combination. Determination of three SNPs of the Klotho gene could help in the prediction of non-cardiovascular death in CKD

    Search for resonances in the mass spectrum of muon pairs produced in association with b quark jets in proton-proton collisions at root 8 and 13 TeV

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    A search for resonances in the mass range 12-70 GeV produced in association with a b quark jet and a second jet, and decaying to a muon pair, is reported. The analysis is based on data from proton-proton collisions at center-of-mass energies of 8 and 13 TeV, collected with the CMS detector at the LHC and corresponding to integrated luminosities of 19.7 and 35.9 fb(-1), respectively. The search is carried out in two mutually exclusive event categories. Events in the first category are required to have a b quark jet in the central region (|| 2.4) and at least one jet in the forward region (|| > 2.4). Events in the second category are required to have two jets in the central region, at least one of which is identified as a b quark jet, no jets in the forward region, and low missing transverse momentum. An excess of events above the background near a dimuon mass of 28 GeV is observed in the 8 TeV data, corresponding to local significances of 4.2 and 2.9 standard deviations for the first and second event categories, respectively. A similar analysis conducted with the 13 TeV data results in a mild excess over the background in the first event category corresponding to a local significance of 2.0 standard deviations, while the second category results in a 1.4 standard deviation deficit. The fiducial cross section measurements and 95% confidence level upper limits on those for a resonance consistent with the 8 TeV excess are provided at both collision energies

    Search for supersymmetry in proton-proton collisions at 13 TeV using identified top quarks

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    A search for supersymmetry is presented based on proton-proton collision events containing identified hadronically decaying top quarks, no leptons, and an imbalance p(T)(miss) in transverse momentum. The data were collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV, and correspond to an integrated luminosity of 35.9 fb(-1). Search regions are defined in terms of the multiplicity of bottom quark jet and top quark candidates, the p(T)(miss) , the scalar sum of jet transverse momenta, and themT2 mass variable. No statistically significant excess of events is observed relative to the expectation from the standard model. Lower limits on the masses of supersymmetric particles are determined at 95% confidence level in the context of simplified models with top quark production. For a model with direct top squark pair production followed by the decay of each top squark to a top quark and a neutralino, top squark masses up to 1020 GeVand neutralino masses up to 430 GeVare excluded. For amodel with pair production of gluinos followed by the decay of each gluino to a top quark-antiquark pair and a neutralino, gluino masses up to 2040 GeVand neutralino masses up to 1150 GeVare excluded. These limits extend previous results.Peer reviewe
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