161 research outputs found

    Effects of ionizing radiation sterilization on microparticulate drug delivery systems based on poly-alfa-hydroxyacids: an overview.

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    Ionizing radiation treatment is particularly advantageous as a sterilization technique for polymeric drug delivery systems. In recent years several authors have investigated this topic with interesting and sometimes controversial results. This overview was aimed at gathering and critically discussing the studies performed on the effect of ionizing radiation sterilization on microparticulate drug delivery systems made of poly-α- hydroxyacids. The results reported in the literature showed that ionizing radiation always led to a decrease in poly-α-hydroxyacids molecular weight. This effect was strictly related to irradiation dose, irradiation conditions, and depended on the starting polymer molecular weight. The presence of a drug and/or an additive inside the polymeric micromatrix could affect polymer behavior upon irradiation and consequently drug release behavior. Electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) proved to be useful techniques to elucidate the radiolytic mechanisms and the drug /polymer interaction upon irradiation

    Biomarkes of aging.

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    Ageing is a complex process that negatively impacts the development of the different systems and its ability to function. On the other hand, the rate of ageing in humans is not uniform, due to genetic heterogeneity and the influence of environmental factors. Thus, the ageing rate, measured as the decline of functional capacity and stress resistance, seems to be different in every individual. Therefore, attempts have been made to analyse this individual age, the so-called biological age, in comparison to chronological age. Age-related changes in body function or composition that could serve as a measure of biological age and predict the onset of age-related diseases and/or residual lifetime are termed biomarkers of ageing. Such biomarkers of ageing should help on the one hand to characterise this biological age and, as age is a major risk factor in many degenerative diseases, could be subsequently used on the other hand to identify individuals at high risk of developing age-associated diseases or disabilities. Unfortunately, most of the markers under discussion are related to age-related diseases rather than to age, so none of these markers discussed in literature is a true biomarker of ageing. Hence, we discuss some disease-related biomarkers useful for a better understanding of ageing and the development of new strategies to counteract it, essential for improving the quality of life of the elderly population. Biomarkers discussed are based on immunosenescence, inflammatory responses and oxidative stress, since the review is based on data from author laboratories rather than on an extensive review of the literature. However, this kind of knowledge is useful to anti-ageing strategies aimed to slow ageing and to postpone death by preventing infectious diseases and delaying the onset of age-related diseases

    Biomarkers of aging

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    Aging is a complex process that negatively impacts the development of the different systems and its ability to function. Moreover, the Aging rate in humans is not the same, principally due to genetic heterogeneity and environmental factors. The aging rate is measured as the decline of functional capacity and stress resistance. Therefore, several attempts have been made to analyse the individual age, ( so-called biological age) compared to chronological age. The biomarkers of aging are age-related body function or composition, these markers aim to assess the biological age and predict the onset of age-related diseases and/or residual lifetime. Such biomarkers should help in one hand to characterise the biological age and on the other hand to identify individuals at high risk of developing age-associated diseases or disabilities. Unfortunately, most of the markers under discussion are related to age-related diseases rather than to age, so none of these markers discussed in literature is a true biomarker of aging. Hence, we discuss some disease-related biomarkers useful for a better understanding of aging and the development of new strategies to counteract it, essential for improving the quality of life of the elderly population

    Age-Related Inflammation: the Contribution of Different Organs, Tissues and Systems. How to Face it for Therapeutic Approaches

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    A typical feature of ageing is a chronic, low-grade inflammation characterized by a general increase in the production of proinflammatory cytokines and inflammatory markers (“inflamm-ageing”). This status may slowly damage one or several organs, especially when unfavorable genetic polymorphisms and epigenetic alterations are concomitant, leading to an increased risk of frailty together with the onset of age-related chronic diseases. The contribution of different tissues (adipose tissue, muscle), organs (brain, liver), immune system and ecosystems (gut microbiota) to age-related inflammation (“inflamm-ageing”) will be discussed in this review in the context of its onset/progression leading to site-restricted and systemic effects. Moreover, some of the possible strategies and therapies to counteract the different sources of molecular mediators which lead to the age-related inflammatory phenotype will be presente

    Breast cancer survival in the US and Europe: a CONCORD high-resolution study.

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    Breast cancer survival is reportedly higher in the US than in Europe. The first worldwide study (CONCORD) found wide international differences in age-standardized survival. The aim of this study is to explain these survival differences. Population-based data on stage at diagnosis, diagnostic procedures, treatment and follow-up were collected for about 20,000 women diagnosed with breast cancer aged 15-99 years during 1996-98 in 7 US states and 12 European countries. Age-standardized net survival and the excess hazard of death up to 5 years after diagnosis were estimated by jurisdiction (registry, country, European region), age and stage with flexible parametric models. Breast cancers were generally less advanced in the US than in Europe. Stage also varied less between US states than between European jurisdictions. Early, node-negative tumors were more frequent in the US (39%) than in Europe (32%), while locally advanced tumors were twice as frequent in Europe (8%), and metastatic tumors of similar frequency (5-6%). Net survival in Northern, Western and Southern Europe (81-84%) was similar to that in the US (84%), but lower in Eastern Europe (69%). For the first 3 years after diagnosis the mean excess hazard was higher in Eastern Europe than elsewhere: the difference was most marked for women aged 70-99 years, and mainly confined to women with locally advanced or metastatic tumors. Differences in breast cancer survival between Europe and the US in the late 1990s were mainly explained by lower survival in Eastern Europe, where low healthcare expenditure may have constrained the quality of treatment

    Measurement of the Ge 70 (n,γ) cross section up to 300 keV at the CERN n-TOF facility

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    ©2019 American Physical Society.Neutron capture data on intermediate mass nuclei are of key importance to nucleosynthesis in the weak component of the slow neutron capture processes, which occurs in massive stars. The (n,γ) cross section on Ge70, which is mainly produced in the s process, was measured at the neutron time-of-flight facility n-TOF at CERN. Resonance capture kernels were determined up to 40 keV neutron energy and average cross sections up to 300 keV. Stellar cross sections were calculated from kT=5 keV to kT=100 keV and are in very good agreement with a previous measurement by Walter and Beer (1985) and recent evaluations. Average cross sections are in agreement with Walter and Beer (1985) over most of the neutron energy range covered, while they are systematically smaller for neutron energies above 150 keV. We have calculated isotopic abundances produced in s-process environments in a 25 solar mass star for two initial metallicities (below solar and close to solar). While the low metallicity model reproduces best the solar system germanium isotopic abundances, the close to solar model shows a good global match to solar system abundances in the range of mass numbers A=60-80.Peer reviewedFinal Published versio

    Patients with migraine with aura have increased flow mediated dilation

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    <p>Abstract</p> <p>Background</p> <p>Endothelium-derived nitric oxide (NO) mediates the arterial dilation following a flow increase (i.e. flow-mediated dilation, FMD), easily assessed in the brachial artery. NO is also involved in cerebral hemodynamics and it is supposed to trigger vascular changes occurring during migraine. This study aimed at investigating whether migraine patients present an altered response to NO also in the peripheral artery system.</p> <p>Methods</p> <p>We enrolled 21 migraineurs (10 with aura [MwA], 11 without aura [MwoA]), and 13 controls. FMD was evaluated with ultrasound in all subjects by measuring the percentage increase of the brachial artery diameter induced by hyperaemia reactive to sustained cuff inflation around the arm above systolic pressure. FMD values were then normalized for shear stress.</p> <p>Results</p> <p>Normalized FMD values were higher in patients with MwA (28.5 10<sup>-2</sup>%.s) than in controls (9.0 10<sup>-2</sup>%.s) and patients with MwoA (13.7 10<sup>-2</sup>%.s) (p < 0.001). FMD was over the median value (19%) in 23.1% of controls, in 45.5% of the MwoA patients, and in 90% of the MwA patients.</p> <p>Conclusions</p> <p>Migraineurs with aura present an excessive arterial response to hyperaemia, likely as an effect of an increased sensitivity to endothelium-derived nitric oxide. This phenomenon observed peripherally might reflect similar characteristics in the cerebral circulation.</p

    The Immune Inhibitory Receptor LAIR-1 Is Highly Expressed by Plasmacytoid Dendritic Cells and Acts Complementary with NKp44 to Control IFNα Production

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    Plasmacytoid dendritic cells (pDCs) are a subset of dendritic cells endowed with the capacity of producing large amounts of IFNα. Here we show that the Leukocyte-Associated Ig-like Receptor-1 (LAIR-1) is abundantly expressed on pDCs (the highest expression among all leukocytes) and its cross-linking inhibits IFNα production in response to Toll-like receptor ligands. Remarkably, LAIR-1 expression in pDCs is down-regulated in the presence of interleukin (IL)-3, thus indicating coordinated functions with NKp44, another pDC inhibitory receptor, which is conversely induced by IL-3. Nevertheless, the expression of NKp44 in pDCs isolated from secondary lymphoid organs, which is thought to be influenced by IL-3, is not coupled to a decreased expression of LAIR-1. Interestingly, pDCs isolated from peripheral blood of systemic lupus erithematosus (SLE) patients express lower levels of LAIR-1 while displaying slight but consistent expression of NKp44, usually undetectable on pDCs derived from healthy donors. Using sera derived from SLE patients, we show that LAIR-1 and NKp44 display synergistic inhibitory effects on IFNα production by interleukin IL-3 cultured pDCs stimulated with DNA immunocomplexes. In conclusion, our results indicate that the inhibitory function of LAIR-1 may play a relevant role in the mechanisms controlling IFNα production by pDCs both in normal and pathological innate immune responses

    First Results of the 140^{140}Ce(n,γ)141^{141}Ce Cross-Section Measurement at n_TOF

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    An accurate measurement of the 140^{140}Ce(n,γ) energy-dependent cross-section was performed at the n_TOF facility at CERN. This cross-section is of great importance because it represents a bottleneck for the s-process nucleosynthesis and determines to a large extent the cerium abundance in stars. The measurement was motivated by the significant difference between the cerium abundance measured in globular clusters and the value predicted by theoretical stellar models. This discrepancy can be ascribed to an overestimation of the 140^{140}Ce capture cross-section due to a lack of accurate nuclear data. For this measurement, we used a sample of cerium oxide enriched in 140^{140}Ce to 99.4%. The experimental apparatus consisted of four deuterated benzene liquid scintillator detectors, which allowed us to overcome the difficulties present in the previous measurements, thanks to their very low neutron sensitivity. The accurate analysis of the p-wave resonances and the calculation of their average parameters are fundamental to improve the evaluation of the 140^{140}Ce Maxwellian-averaged cross-section
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