106 research outputs found

    Molecular mechanisms of neurogenic aging in the adult mouse subventricular zone

    Get PDF
    In the adult rodent brain, the continuous production of new neurons by neural stem/progenitor cells (NSPCs) residing in specialized neurogenic niches and their subsequent integration into pre-existing cerebral circuitries supports odour discrimination, spatial learning, and contextual memory capabilities. Aging is recognized as the most potent negative regulator of adult neurogenesis. The neurogenic process markedly declines in the aged brain, due to the reduction of the NSPC pool and the functional impairment of the remaining NSPCs. This decline has been linked to the progressive cognitive deficits of elderly individuals and it may also be involved in the onset/progression of neurological disorders. Since the human lifespan has been dramatically extended, the incidence of age-associated neuropsychiatric conditions in the human population has increased. This has prompted efforts to shed light on the mechanisms underpinning the age-related decline of adult neurogenesis, whose knowledge may foster therapeutic approaches to prevent or delay cognitive alterations in elderly patients. In this review, we summarize recent progress in elucidating the molecular causes of neurogenic aging in the most abundant NSPC niche of the adult mouse brain: the subventricular zone (SVZ). We discuss the age-associated changes occurring both in the intrinsic NSPC molecular networks and in the extrinsic signalling pathways acting in the complex environment of the SVZ niche, and how all these changes may steer young NSPCs towards an aged phenotype

    Low-level 226Ra determination in groundwater by SF-ICP-MS: optimization of separation and pre-concentration methods

    Get PDF
    Inductively coupled plasma mass spectrometry (ICP-MS) techniques have been widely used for analysis of long-lived environmental radionuclides. In this paper, we present an optimization of the sector field (SF)-ICP-MS technique for the analysis of 226Ra in groundwater samples using a method of pre-concentration of radium in water samples. The separation protocol and a sequential application of ion exchange and extraction chromatography have been optimized, and related polyatomic interferences and matrix effects affecting the 226Ra signal were investigated. Analyzing 12 replicates (water spiking at 22 fg g−1 of 226Ra), the 226Ra recovery efficiency close to 100 % has been obtained. The instrumental 226Ra detection limit of 0.09 fg g−1 (3σ criterion) and the absolute detection limit of 0.05 fg in a 25-mL groundwater sample have been reached. An optimization of the radium separation method and a pre-concentration of radium in groundwater samples led to high radium recoveries, almost up to 100 %. The same could be said with respect to the separation of the interfering elements, important for the quantitative 226Ra analysis by SF-ICP-MS. The improvements in the separation and pre-concentration techniques also helped to improve the 226Ra detection limit down to 0.05 fg/25 mL of groundwater sample

    Surgical Management of Medication-Related Osteonecrosis of the Jaw Patients Related to Dental Implants

    Get PDF
    The aim of the present study is to report a case series of patients with peri-implant medication-related osteonecrosis of the jaw (MRONJ), in particular describing the onset of the condition and surgical treatment outcome

    Effect of different butyrate supplementations on growth and health of weaning pigs challenged or not with E. coli K88

    Get PDF
    In a full factorial design (4 diets X challenge, Yes/No), 72 weaning pigs were assigned to one of the diets: Control; experimental diets, obtained with the addition of 2 g/kg free sodium butyrate (fNaB), or 0.6 g/kg fat-protected sodium butyrate (pNaB), or 2 g/kg INVE-NutriAd commercial mixture (Mix, based on 75 g/kg protected butyrate). Oral challenge with Escherichia coli K88 was done on 2/3 of pigs on d 7. Pigs were slaughtered on d 13. The mortality in challenged pigs, tended to be higher in control group (50.0 %) than in the three supplemented groups (23.5%). Growth tended to be increased averagely by the supplements (P = 0.100) after the challenge, that also significantly reduced growth. In general the diet did not affect the fecal shedding of Escherichia coli and Lactobacilli, the K88-specific IgA activity in blood, the morphology of oxyntic mucosa and the expression of H+/K+-ATPase gene. The supplementations tended to increase villous length of jejunum (P = 0.101). On the whole, growth, villous height and surviving rate can be positively affected either when the supplementation is done by free butyrate, by protected butyrate or by the special Inve Nutri-Ad product and these effects are distributed both on pigs infected or not with Escherichia coli K88

    Mobile elites at Frattesina: flows of people in a Late Bronze Age ‘port of trade’ in northern Italy

    Get PDF
    Following a mid twelfth-century BC demographic crisis, Frattesina, in northern Italy, arose as a prominent hub linking continental Europe and the Mediterranean, as evidenced by the remarkable variety of exotic materials and commodities discovered at the site. Debate persists, however, about the extent to which migrants influenced the foundation and development of Frattesina. The authors present the results of strontium isotope analyses, which suggest significant migration to the site, particularly of elites, mostly from within a 50km radius. Among these non-indigenous people, the authors identify a \u2018warrior-chief\u2019, whom they interpret as representing a new, more hierarchical society

    The provenance of the raw material and the manufacturing technology of copper artefacts from the Copper Age hoard from Magyaregres, Hungary.

    Get PDF
    In 2016, a Stollhof-type copper hoard was found during an excavation in Magyaregres, Hungary. It was placed in a cooking pot, and deposited upside down within the boundaries of an Early Copper Age settlement. Similar hoards dating to the end of the 5th millennium BCE are well-known from Central Europe, however, this hoard represents the only one so far with thoroughly documented finding circumstances. The hoard contained 681 pieces of copper, 264 pieces of stone and a single Spondylus bead, along with 19 pieces of small tubular spiral copper coils, three spiral copper bracelets, and two large, spectacle spiral copper pendants. Until now, information on the provenance of raw materials and how such copper artefacts were manufactured has not been available. The artefacts were studied under optical microscopes to reveal the manufacturing process. Trace elemental composition (HR-ICP-MS) and lead isotope ratios (MC-ICP-MS) were measured to explore the provenance of raw materials. The ornaments were rolled or folded and coiled from thin sheets of copper using fahlore copper probably originating from the Northwestern Carpathians. A complex archaeological approach was employed to reveal the provenance, distribution and the social roles the ornaments could have played in the life of a Copper Age community. Evidence for local metallurgy was lacking in contemporaneous Transdanubian sites, therefore it is likely that the items of the hoard were manufactured closer to the raw material source, prior to being transported to Transdanubia as finished products. The method of deposition implies that such items were associated with special social contexts, represented exceptional values, and the context of deposition was also highly prescribed. The Magyaregres hoard serves as the first firm piece of evidence for the existence of a typologically independent Central European metallurgical circle which exploited the raw material sources located within its distribution

    Cryogenic Detectors for Rare Alpha Decay Search: A New Approach

    Get PDF
    The detection of 148^{148} Sm alpha decay with a precise measured half-life of (6.4−1.3+1.2)×1015y\left( {6.4_{-1.3}^{+1.2} }\right) \times 10^{15}y and a Q-value of 1987.3 ±\pm 0.5 keV was achieved by a new experimental approach, where a conventional ZnWO 4_{4} scintillating crystal doped with enriched 148^{148} Sm isotope is operated as a cryogenic scintillating bolometer (phonon and light channel) at mK-temperatures

    Investigation on rare nuclear processes in Hf nuclides

    Get PDF
    In this work, a review of recent studies concerning rare nuclear processes in Hf isotopes is presented. In particular, the investigations using HP-Ge spectrometry and Hf-based crystal scintillators are focused; the potentiality and the results of the "source = detector" approach are underlined. In addition, a short introduction concerning the impact of such kind of research in the context of astroparticle and nuclear physics is pointed out. In particular, the study of α decay and double beta decay of 174Hf, 176Hf, 177Hf, 178Hf, 179Hf, 180Hf isotopes either to the ground state or to the lower bounded levels have been discussed. The observation of α decay of 174Hf isotope to the ground state with a T1/2=7.0(1.2)×1016 y is reported and discussed. No decay was detected for α decay of 174Hf isotope at the first excited level of daughter and of 176Hf, 177Hf, 178Hf, 179Hf, 180Hf isotopes either to the ground state or to the lower bounded levels. The T1/2 lower limits for these decays are at the level of 1016–1020 y. Nevertheless, the T1/2 lower limits for the transitions of 176Hf→172Yb (0+→0+) and 177Hf→173Yb (7/2−→5/2−) are near to the theoretical predictions, giving hope to their observation in the near future. All the other experimental limits (∼1016–1020 y) are absolutely far from the theoretical expectations. The experiments investigating the 2ϵ and ϵβ+ processes in 174Hf are also reported; the obtained half-life limits are set at the level of 1016–1018 y. Moreover, we estimate the T1/2 of 2ν2ϵ of 174Hf decay at the level of (0.3–6) × 1021 y (at now the related measured lower limit is 7.1×1016 y)
    • …
    corecore