656 research outputs found

    Pomacea canaliculata ampullar proteome: A nematode-based bio-pesticide induces changes in metabolic and stress-related pathways

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    Pomacea canaliculata is a freshwater gastropod known for being both a highly invasive species and one of the possible intermediate hosts of the mammalian parasite Angiostrongylus cantonensis. With the aim of providing new information concerning P. canaliculata biology and adaptability, the first proteome of the ampulla, i.e., a small organ associated with the circulatory system and known as a reservoir of nitrogen-containing compounds, was obtained. The ampullar proteome was derived from ampullae of control snails or after exposure to a nematode-based molluscicide, known for killing snails in a dose-and temperature-dependent fashion. Proteome analysis revealed that the composition of connective ampulla walls, cell metabolism and oxidative stress response were affected by the biopesticide. Ultrastructural investigations have highlighted the presence of rhogocytes within the ampullar walls, as it has been reported for other organs containing nitrogen storage tissue. Collected data suggested that the ampulla may belong to a network of organs involved in controlling and facing oxidative stress in different situations. The response against the nematode-based molluscicide recalled the response set up during early arousal after aestivation and hibernation, thus encouraging the hypothesis that metabolic pathways and antioxidant defences promoting amphibiousness could also prove useful in facing other challenges stimulating an oxidative stress response, e.g., immune challenges or biocide exposure. Targeting the oxidative stress resistance of P. canaliculata may prove helpful for increasing its susceptibility to bio-pesticides and may help the sustainable control of this pest’s diffusion

    Effect of grain refinement on enhancing critical current density and upper critical field in undoped MgB2 ex-situ tapes

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    Ex-situ Powder-In-Tube MgB2 tapes prepared with ball-milled, undoped powders showed a strong enhancement of the irreversibility field H*, the upper critical field Hc2 and the critical current density Jc(H) together with the suppression of the anisotropy of all of these quantities. Jc reached 104 A/cm2 at 4.2 K and 10 T, with an irreversibility field of about 14 T at 4.2 K, and Hc2 of 9 T at 25 K, high values for not-doped MgB2. The enhanced Jc and H* values are associated with significant grain refinement produced by milling of the MgB2 powder, which enhances grain boundary pinning, although at the same time also reducing the connectivity from about 12% to 8%. Although enhanced pinning and diminished connectivity are in opposition, the overall influence of ball milling on Jc is positive because the increased density of grains with a size comparable with the mean free path produces strong electron scattering that substantially increases Hc2, especially Hc2 perpendicular to the Mg and B planes.Comment: 26 pages, 9 figures, submitted to J. Appl. Phy

    Comparasion between European elite senior and junior female table tennis players

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    The aim of the study was to compare elite junior and senior women table tennis players, using three parameters of the table tennis: rally length, serve and receive analysis. Twentyfive junior and twenty-five elite senior matches were analysed (total: 263 sets and 4958 points) between players ranked in Top 25 in ETTU rankings in the last two years. All the athletes used an offensive style of play. The results of non-parametric Mann-Whitney U Test, showed a significantly higher rally length in senior compared to junior category (4.46 vs. 3.93). Moreover, the results of Pearson’s Chi-square tests show an association between the age categories and selected parameters (laterality, technique and placement) for both serve and receive. Different behavior between the two categories was noted. The senior players used more the flip technique (22.2 % vs 14.7 %) and short push to return the services of the opponents (32.5 % vs 26.0 %). These results provide useful information to analyze junior players’ behavior compared to the senior players in order to plan specific training sessions. It can be also useful to identify some parameters as predictors of the future success for junior players

    Exposure to particulate matter and risk of amyotrophic lateral sclerosis: A case-control study in Northern Italy

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    Background: Amyotrophic lateral sclerosis (ALS) is progressive neurodegenerative disease with still unknown etiology. Role of occupational and environmental risk factors has been investigated, including outdoor air pollutants, which have been recently associated to an excess disease risk. We carried out a case-control study in order to assess if environmental exposure to particulate matter ≤10 µm (PM10) may increase ALS risk. Methods: We recruited patients referred to the Modena Neurology Unit between 1994-2015 and controls from the Modena province population. Using a validated geographical information system-based dispersion model, we geocoded subjects’ addresses of residence at the time of diagnosis and we estimated outdoor air PM10 concentrations for each subjects. We computed odds ratio (OR) and 95% confidence interval (CI) of ALS according to increasing PM10 exposure, using an unconditional logistic regression model age- and sex-adjusted. Results: For the 132 study participants (52 cases/80 controls), mean of annual average and maximum PM10 concentrations were 5.2 and 38.6µg/m3, respectively. Using fixed cutpoints at 5, 10 and 20 of average annual PM10 concentrations, compared with subjects <5µg/m3, we did not find evidence for an excess ALS risk associated with PM10 exposure, since OR was 0.87 (95% CI 0.39-1.96), 0.94 (0.24-3.70), and 0.87 (0.05-15.01) at 5-10, 10-20 and ≥20µg/m3, respectively. Using maximum annual PM10 concentrations, we found an excess ALS risk for subjects exposed at 10-20µg/m3 (OR=4.27, 0.69-26.51) compared with exposure below 10µg/m3, although the risk tended to decrease at higher PM10 concentrations, with OR of 1.49 (0.39-5.75) at 20-50, and 1.16 (0.98-4.82) at ≥50µg/m3. Conclusions:Our findings do not suggest that PM10exposure is associated with ALS risk. However, some evidence of an increased risk associated with maximum annual exposure concentrations, although statistically imprecise, suggests the need of further investigations, also considering the high concentrations of particulate matter characterizing Northern Italy

    Immune contribution to tentacle regeneration in adult mollusc and cnidarian models

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    Histological studies focusing on the early cephalic tentacle regeneration in P. canaliculata, have demonstrated that wound closure and blastema formation took place within 24 h post amputation (hpa). A Matlab® plugin allowed the semi-automated identification and quantification of a phagocytic hemocyte sub-population in the blastema. Flow cytometry analysis showed that the injection of the phagocyte-specific drug Clophosome® (45 µg/g snail) could transiently remove circulating hemocytes, that recovered the pre-treatment level within 24 h. Consistently, histological experiment demonstrated that rare hemocytes were present in the early regenerating tentacles of Clophosome®-injected snail

    Recent X-ray Observations and the Evolution of Hot Gas in Elliptical Galaxies: Evidence for Circumgalactic Gas

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    X-ray emitting gaseous halos, such as that in elliptical galaxies like NGC 4472, cannot have been produced solely from gas expelled from galactic stars. In traditional models for the evolution of hot interstellar gas (cooling flows) in ellipticals, the galaxies are assumed to have been cleared of gas by SNII-driven winds at some early time then gas is subsequently replenished by mass loss from an evolving population of old stars. To test this, we accurately determine the stellar and dark halo mass of NGC 4472 using hydrostatic equilibrium, then solve the standard time-dependent cooling flow equations to recover the observed hot gas temperature and density distributions when evolved to the present time. This procedure fails: the computed gas density gradient is too steep, the total gas mass is too low, and the gas temperatures are much too low. All variants on this basic procedure also fail: increasing the SNIa rate, using the mass dropout assumption, arbitrarily adjusting uncertain coefficients, etc. However, agreement is achieved if the galaxy is supplied with additional, spatially-extended hot gas early in its evolution. This old ``circumgalactic'' gas can be retained to the present time and may be related to cosmological ``secondary infall''.Comment: 15 pages in two-column AASTEX LaTeX including 1 table and 8 figures; abstract corrected in replacement; accepted by Astrophysical Journa

    Type 3 hypersensitivity in COVID-19 vasculitis

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    Coronavirus Disease 2019 (COVID-19) is an ongoing public health emergency and new knowledge about its immunopathogenic mechanisms is deemed necessary in the attempt to reduce the death burden, globally. For the first time in worldwide literature, we provide scientific evidence that in COVID-19 vasculitis a life-threatening escalation from type 2 T-helper immune response (humoral immunity) to type 3 hypersensitivity (immune complex disease) takes place. The subsequent deposition of immune complexes inside the vascular walls is supposed to induce a severe inflammatory state and a cytokine release syndrome, whose interleukin-6 is the key myokine, from the smooth muscle cells of blood vessels
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