3,349 research outputs found

    Modeling lightning-NOx chemistry on a sub-grid scale in a global chemical transport model

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    For the first time, a plume-in-grid approach is implemented in a chemical transport model (CTM) to parameterize the effects of the nonlinear reactions occurring within high concentrated NO<sub><i>x</i></sub> plumes from lightning NO<sub><i>x</i></sub> emissions (LNO<sub><i>x</i></sub>) in the upper troposphere. It is characterized by a set of parameters including the plume lifetime, the effective reaction rate constant related to NO<sub><i>x</i></sub>–O<sub>3</sub> chemical interactions, and the fractions of NO<sub><i>x</i></sub> conversion into HNO<sub>3</sub> within the plume. Parameter estimates were made using the Dynamical Simple Model of Atmospheric Chemical Complexity (DSMACC) box model, simple plume dispersion simulations, and the 3-D Meso-NH (non-hydrostatic mesoscale atmospheric model). In order to assess the impact of the LNO<sub><i>x</i></sub> plume approach on the NO<sub><i>x</i></sub> and O<sub>3</sub> distributions on a large scale, simulations for the year 2006 were performed using the GEOS-Chem global model with a horizontal resolution of 2° × 2.5°. The implementation of the LNO<sub><i>x</i></sub> parameterization implies an NO<sub><i>x</i></sub> and O<sub>3</sub> decrease on a large scale over the region characterized by a strong lightning activity (up to 25 and 8 %, respectively, over central Africa in July) and a relative increase downwind of LNO<sub><i>x</i></sub> emissions (up to 18 and 2 % for NO<sub><i>x</i></sub> and O<sub>3</sub>, respectively, in July). The calculated variability in NO<sub><i>x</i></sub> and O<sub>3</sub> mixing ratios around the mean value according to the known uncertainties in the parameter estimates is at a maximum over continental tropical regions with ΔNO<sub><i>x</i></sub> [−33.1, +29.7] ppt and ΔO<sub>3</sub> [−1.56, +2.16] ppb, in January, and ΔNO<sub><i>x</i></sub> [−14.3, +21] ppt and ΔO<sub>3</sub> [−1.18, +1.93] ppb, in July, mainly depending on the determination of the diffusion properties of the atmosphere and the initial NO mixing ratio injected by lightning. This approach allows us (i) to reproduce a more realistic lightning NO<sub><i>x</i></sub> chemistry leading to better NO<sub><i>x</i></sub> and O<sub>3</sub> distributions on the large scale and (ii) to focus on other improvements to reduce remaining uncertainties from processes related to NO<sub><i>x</i></sub> chemistry in CTM

    25 hydroxyvitamin D deficiency and its relationship to autoimmune thyroid disease in the elderly

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    Background: Low 25(OH) vitamin D levels have been associated with several autoimmune diseases and recently with autoimmune thyroiditis (AT). The aim of the study was to investigate the association of AT with low 25(OH) vitamin D levels in the elderly. Methods: One hundred sixty-eight elderly subjects (mean age: 81.6 ± 9.4 years) were enrolled. Serum levels of 25(OH) vitamin D, anti-thyroid peroxidase (TPO-Ab), anti-thyroglobulin (TG-Ab) antibodies, free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) were measured. Results: The prevalence of AT was significantly higher in subjects with vitamin D deficiency (25(OH) vitamin D < 20 ng/mL) when compared with subjects with normal 25(OH) vitamin D (25(OH) vitamin D ≥ 20 ng/mL) levels (28% vs. 8%, respectively, p = 0.002). Patients with AT and vitamin D deficiency had a comparable hormonal profile compared to patients with AT and vitamin D sufficiency in terms of TSH (p = 0.39), FT3 (p = 0.30), FT4 (p = 0.31), TG-Ab (0.44) and TPO-Ab (0.35). Interestingly, a significant correlation between 25(OH) vitamin D and TPO-Ab (r = −0.27, p = 0.03) and FT3 (r = 0.35, p = 0.006) has been found in subjects with AT while no correlation was found between 25(OH) vitamin D levels and TG-Ab (r = −0.15, p = 0.25), TSH (r = −0.014, p = 0.09) and FT4 (r = 0.13, p = 0.32). Conclusions: These findings suggest that vitamin D deficiency was significantly associated with AT in the elderly. Therefore, the screening for AT should be suggested in subjects with vitamin D deficiency

    Biological effects of EF24, a curcumin derivative, alone or combined with mitotane in adrenocortical tumor cell lines

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    Background: Curcumin has numerous properties and is used in many preclinical conditions, including cancer. It has low bioavailability, while its derivative EF24 shows enhanced solubility. However, its effects have never been explored in adrenocortical tumor cell models. The efficacy of EF24 alone or combined with mitotane (reference drug for adrenocortical cancer) was evaluated in two adrenocortical tumor cell lines, SW13 and H295R. Method and Results: EF24 reduced cell viability with an IC50 (half maximal inhibitory concentration) of 6.5 \ub1 2.4 \ub5M and 4.9 \ub1 2.8 \ub5M for SW13 and H295R cells, respectively. Combination index (EF24 associated with mitotane) suggested an additivity effect in both cell lines. Cell cycle analysis revealed an increase in subG0/G1 phase, while motility assay showed a decrease in migratory cell capacity, and similarly, clonogenic assay indicated that EF24 could reduce colony numbers. Furthermore, Wnt/\u3b2-catenin, NF-\u3baB, MAPK, and PI3k/Akt pathways were modulated by Western blot analysis when treating cells with EF24 alone or combined with mitotane. In addition, intracellular reactive oxygen species levels increased in both cell lines. Conclusion: This work analyzed EF24 in adrenocortical tumor cell lines for the first time. These results suggest that EF24 could potentially impact on adrenocortical tumors, laying the foundation for further research in animal models

    Robust entanglement of a micromechanical resonator with output optical fields

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    We perform an analysis of the optomechanical entanglement between the experimentally detectable output field of an optical cavity and a vibrating cavity end-mirror. We show that by a proper choice of the readout (mainly by a proper choice of detection bandwidth) one can not only detect the already predicted intracavity entanglement but also optimize and increase it. This entanglement is explained as being generated by a scattering process owing to which strong quantum correlations between the mirror and the optical Stokes sideband are created. All-optical entanglement between scattered sidebands is also predicted and it is shown that the mechanical resonator and the two sideband modes form a fully tripartite-entangled system capable of providing practicable and robust solutions for continuous variable quantum communication protocols

    No association between frailty index and epigenetic clocks in Italian semi-supercentenarians

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    Centenarians experience successful ageing, although they still present high heterogeneity in their health status. The frailty index is a biomarker of biological age, able to capture such heterogeneity, even at extreme old age. At the same time, other biomarkers (e.g., epigenetic clocks) may be informative the biological age of the individual and potentially describe the ageing status in centenarians. In this article, we explore the relationship between epigenetic clocks and frailty index in a cohort of Italian centenarians. No association was reported, suggesting that these two approaches may describe different aspects of the same ageing process

    Gender differences in internet addiction: A study on variables related to its possible development

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    Internet addiction and its related variables (i.e., internet gaming addiction, social media addiction, fear of missing out, phubbing) have mostly been investigated in the general population without considering possible gender differences. The present study aimed to investigate the specific characteristics of men and women in the possible development of pathological behaviors related to internet addiction. A total of 276 participants (of ages ranging from 18 to 30 years old) were recruited in the study (46.7% were males) and responded to online questionnaires on variables related to internet addiction and psychological traits. The results showed that gender represents a key factor in explaining why individuals are addicted to the internet in different ways. Stepwise linear regression analyses showed that both genders shared social media addiction as the primary predictor of internet addiction but also exclusive predictors for each gender. Knowing the variables underlying the development of internet Addiction can be useful for both prevention and treatment and tailoring intervention for this addictive behavior

    Effect of human rotavirus vaccine on severe diarrhea in African infants.

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    BACKGROUND: Rotavirus is the most common cause of severe gastroenteritis among young children worldwide. Data are needed to assess the efficacy of the rotavirus vaccine in African children. METHODS: We conducted a randomized, placebo-controlled, multicenter trial in South Africa (3166 infants; 64.1% of the total) and Malawi (1773 infants; 35.9% of the total) to evaluate the efficacy of a live, oral rotavirus vaccine in preventing severe rotavirus gastroenteritis. Healthy infants were randomly assigned in a 1:1:1 ratio to receive two doses of vaccine (in addition to one dose of placebo) or three doses of vaccine--the pooled vaccine group--or three doses of placebo at 6, 10, and 14 weeks of age. Episodes of gastroenteritis caused by wild-type rotavirus during the first year of life were assessed through active follow-up surveillance and were graded with the use of the Vesikari scale. RESULTS: A total of 4939 infants were enrolled and randomly assigned to one of the three groups; 1647 infants received two doses of the vaccine, 1651 infants received three doses of the vaccine, and 1641 received placebo. Of the 4417 infants included in the per-protocol efficacy analysis, severe rotavirus gastroenteritis occurred in 4.9% of the infants in the placebo group and in 1.9% of those in the pooled vaccine group (vaccine efficacy, 61.2%; 95% confidence interval, 44.0 to 73.2). Vaccine efficacy was lower in Malawi than in South Africa (49.4% vs. 76.9%); however, the number of episodes of severe rotavirus gastroenteritis that were prevented was greater in Malawi than in South Africa (6.7 vs. 4.2 cases prevented per 100 infants vaccinated per year). Efficacy against all-cause severe gastroenteritis was 30.2%. At least one serious adverse event was reported in 9.7% of the infants in the pooled vaccine group and in 11.5% of the infants in the placebo group. CONCLUSIONS: Human rotavirus vaccine significantly reduced the incidence of severe rotavirus gastroenteritis among African infants during the first year of life. (ClinicalTrials.gov number, NCT00241644.

    Prunus spinosa extract loaded in biomimetic nanoparticles evokes in vitro anti-inflammatory and wound healing activities

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    Prunus spinosa fruits (PSF) contain different phenolic compounds showing antioxidant and anti-inflammatory activities. Innovative drug delivery systems such as biomimetic nanoparti-cles could improve the activity of PSF extract by promoting (i) the protection of payload into the lipidic bilayer, (ii) increased accumulation to the diseased tissue due to specific targeting properties, (iii) improved biocompatibility, (iv) low toxicity and increased bioavailability. Using membrane proteins extracted from human monocyte cell line THP-1 cells and a mixture of phospholipids, we formulated two types of PSF-extract-loaded biomimetic vesicles differing from each other for the presence of either 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) or 1,2-dioleoyl-sn-glycero-3-phospho-(1\u2032-rac-glycerol) (DOPG). The biological activity of free extract (PSF), compared to both types of extract-loaded vesicles (PSF-DOPCs and PSF-DOPGs) and empty vesicles (DOPCs and DOPGs), was evaluated in vitro on HUVEC cells. PSF-DOPCs showed preferential incorporation of the extract. When enriched into the nanovesicles, the extract showed a significantly increased anti-inflammatory activity, and a pronounced wound-healing effect (with PSF-DOPCs more efficient than PSF-DOPG) compared to free PSF. This innovative drug delivery system, combining nutraceuti-cal active ingredients into a biomimetic formulation, represents a possible adjuvant therapy for the treatment of wound healing. This nanoplatform could be useful for the encapsulation/enrichment of other nutraceutical products with short stability and low bioavailability

    A Novel 3D In Vitro Platform for Pre-Clinical Investigations in Drug Testing, Gene Therapy, and Immuno-oncology.

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    Tumors develop within complex cell-to-cell interactions, with accessory cells playing a relevant role starting in the early phases of cancer progression. This event occurs in a three-dimensional (3D) environment, which to date, has been difficult to reproduce in vitro due to its complexity. While bi-dimensional cultures have generated substantial data, there is a progressive awareness that 3D culture strategies may rapidly increase the understanding of tumor development and be used in anti-cancer compound screening and for predicting response to new drugs utilizing personalized approaches. However, simple systems capable of rapidly rebuilding cancer tissues ex-vivo in 3D are needed and could be used for a variety of applications. Therefore, we developed a flat, handheld and versatile 3D cell culture bioreactor that can be loaded with tumor and/or normal cells in combination which can be monitored using a variety of read-outs. This biocompatible device sustained 3D growth of tumor cell lines representative of various cancers, such as pancreatic and breast adenocarcinoma, sarcoma, and glioblastoma. The cells repopulated the thin matrix which was completely separated from the outer space by two gas-permeable membranes and was monitored in real-time using both microscopy and luminometry, even after transportation. The device was tested in 3D cytotoxicity assays to investigate the anti-cancer potential of chemotherapy, biologic agents, and cell-based therapy in co-cultures. The addition of luciferase in target cancer cells is suitable for comparative studies that may also involve parallel in vivo investigations. Notably, the system was challenged using primary tumor cells harvested from lung cancer patients as an innovative predictive functional assay for cancer responsiveness to checkpoint inhibitors, such as nivolumab. This bioreactor has several novel features in the 3D-culture field of research, representing a valid tool useful for cancer investigations, drug screenings, and other toxicology approaches
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