66 research outputs found

    Ultrafine Magnetite Nanopowder: Synthesis, Characterization, and Preliminary Use as Filler of Polymethylmethacrylate Nanocomposites

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    Magnetite (Fe3O4) nanoparticles prepared by microwave-assisted hydrothermal synthesis have been characterized in terms of morphological and structural features. Electron micrographs collected in both scanning (SEM) and transmission (TEM) modes and evaluations of X-ray powder diffraction (XRD) patterns have indicated the achievement of a monodispersed crystallite structure with particles having an average size around 15–20 nm. Structural investigations by Micro-Raman spectroscopy highlighted the obtainment of magnetite nanocrystals with a partial surface oxidation to maghemite (γ-Fe3O4). Preliminary attention has been also paid to the use of these magnetite nanoparticles as filler for a commercial polymethylmethacrylate resin. Hybrid formulations containing up to 3 wt% of nanoparticles were prepared by melt blending and characterized by calorimetric and thermogravimetric tests. For sake of comparison, same formulations containing commercial Fe3O4nanoparticles are also reported. Calorimetric characterization indicates an increase of both glass transition temperature and thermal stability of the nanocomposite systems when loaded with the synthesized magnetite nanoparticles rather then loaded with the same amount of commercial Fe3O4. This first observation represents just one aspect of the promising potentiality offered by the novel magnetic nanoparticles when mixed with PMMA

    Evaluation of neurocognitive abilities in children affected by obstructive sleep apnea syndrome before and after adenotonsillectomy

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    Obstructive sleep apnoea syndrome (OSAS) is the most severe form of sleep-related disordered breathing (SRDB) and is characterised by snoring, apnoeas, and/or hypopnoeas associated to hypoxia, hypercarbia, or repeated arousals from sleep. OSAS has three major categories of morbidities: neurobehavioural, cardiovascular and somatic growth failure. The gold standard for objective diagnosis of obstructive-SRDB severity is polysomnography (PSG). The indication for surgical treatment in children is moderate-severe OSAS (AHI, apnoea hypopnoea index > 5/h) and in mild OSAS (AHI 2-5/h) with complications or morbidity. The entire spectrum of PSG-defined SRDB (ranging from Primary Snoring to severe OSAS) may correlate with behavioural, attentional and executive function deficits relating to hypoxia and sleep disruption: in some cases, these alterations may mimic attention deficit hyperactivity disorder (ADHD). The aim of this research was to evaluate visuoperceptual and constructional abilities, paediatric sleep questionnaire and polysomnographic scores before and 6 months after adenotonsillectomy with objective and subjective information. We included 59 children who underwent neuropsychiatric and otolaryngologist clinical evaluation and the Beery-Buktenica Developmental Test of Visual-Motor Integration (VMI); children parents were asked to fill in the Paediatric Sleep Questionnaire (PSQ); each child underwent PSG. At 6 months after adenotonsillectomy, all patients were evaluated again. There is a significant difference in PSQ parameters, VMI standard, visual tests scores and PSG parameters before and after adenotonsillectomy in children affected by OSAS. These results showed the achievement of therapeutic benefits with improvement of the quality of life for both children and their parents

    Caratterizzazione della taspina ed attività  su cute umana coltivata di "sangre de grado" (<i>Croton lechleri</i> Müll. Arg.)

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    Tra le piante peruviane più interessanti per la loro azione antivirale ed immunomodulante spicca Croton lechleri (sangre de grado o de drago) al quale si attribuiscono effetti antinfiammatori, immunomodulatori ed antivirali che la rendono un candidato ideale per studi più approfonditi. Poiché Croton lechleri è una pianta da secoli conosciuta dalla popolazione peruviana come riparatore di ferite e disinfettante, abbiamo ritenuto interessante quantificare e caratterizzare la sostanza che viene considerata come la più importante per l’attività di questi estratti: la taspina

    The blue lizard spandrel and the island syndrome

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    <p>Abstract</p> <p>Background</p> <p>Many small vertebrates on islands grow larger, mature later, lay smaller clutches/litters, and are less sexually dimorphic and aggressive than their mainland relatives. This set of observations is referred to as the 'Island Syndrome'. The syndrome is linked to high population density on islands. We predicted that when population density is low and/or fluctuating insular vertebrates may evolve correlated trait shifts running opposite to the Island Syndrome, which we collectively refer to as the 'reversed island syndrome' (RIS) hypothesis. On the proximate level, we hypothesized that RIS is caused by increased activity levels in melanocortin receptors. Melanocortins are postranslational products of the proopiomelanocortin gene, which controls pleiotropically pigmentation, aggressiveness, sexual activity, and food intake in vertebrates.</p> <p>Results</p> <p>We tested the RIS hypothesis performing a number of behavioral, genetic, and ontogenetic tests on a blue colored insular variant of the Italian Wall lizard <it>Podarcis sicula</it>, living on a small island off the Southern Italian coast. The population density of this blue-colored variant was generally low and highly fluctuating from one year to the next.</p> <p>In keeping with our predictions, insular lizards were more aggressive and sexually dimorphic than their mainland relatives. Insular males had wide, peramorphic heads. The growth rate of insular females was slower than growth rates of mainland individuals of both sexes, and of insular males. Consequently, size and shape dimorphism are higher on the Island. As predicted, melanocortin receptors were much more active in individuals of the insular population. Insular lizards have a higher food intake rate than mainland individuals, which is consistent with the increased activity of melanocortin receptors. This may be adaptive in an unpredictable environment such as Licosa Island. Insular lizards of both sexes spent less time basking than their mainland relatives. We suspect this is a by-product (spandrel) of the positive selection for increased activity of melanocortins receptors.</p> <p>Conclusions</p> <p>We contend that when population density is either low or fluctuating annually as a result of environmental unpredictability, it may be advantageous to individuals to behave more aggressively, to raise their rate of food intake, and allocate more energy into reproduction.</p

    Fertility-Sparing Treatment for Early-Stage Cervical Cancer ≥ 2 cm: A Problem with a Thousand Nuances—A Systematic Review of Oncological Outcomes.

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    BACKGROUND: Fertility-sparing treatments (FSTs) have played a crucial role in the management of early-stage cervical cancer (ECC). The guidelines have recognized various approaches, depending on the tumor stage and other risk factors such as histotype and lymphovascular positivity. Much more debate has centered around the boundary within which these treatments should be considered. Indeed, these are methods to be reserved for ECC, but tumor size may represent the most significant limitation. In particular, there is no consensus on the strategy to be adopted in the case of ECC ≥ 2 cm. Therefore, this systematic review was to collect the literature evidence regarding the management of these patients. METHODS: Following the recommendations in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, we systematically searched the Pubmed and Scopus databases was conducted in April 2022, from the date of the first publication. We made no limitation on the country. We included all studies containing data on disease-free survival, overall survival, recurrence rate (RR), or complete response rate (CRR) to chemotherapy. RESULTS: Twenty-six studies fulfilled the inclusion criteria, and 691 patients were analyzed regarding FST. Surgery-based FST showed an RR of between 0 and 42.9%, which drops to 12.9% after excluding the vaginal or minimally invasive approaches. Furthermore, papers regarding FST based on the neoadjuvant chemotherapy (NACT) approach showed a CRR of between 21.4 and 84.5%, and an RR of between 0 and 22.2% CONCLUSION: This paper focused on the significant heterogeneity present in the clinical management of FST of ECC ≥ 2 cm. Nevertheless, from an oncological point of view, approaches limited to the minimally invasive or vaginal techniques showed the highest RR. Vice versa, the lack of standardization of NACT schemes and the wealth of confounders to be attributed to the histological features of the tumor make it difficult, if not impossible, to set a standard of treatment. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1245/s10434-022-12436-w

    Analisi fitochimica e attività biologica in vitro di <i>Minthostachys setosa</i> (Biq. Epling.)

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    Il nostro studio si è basato sulla caratterizzazione fitochimica dell’olio essenziale e dei vari estratti ottenibili dalla Minthostachys setosa non trascurando la loro attività antibatterica e antifunginea sia su patogeni umani che vegetali per trovare conferma scientifica dell’uso fatto dalle popolazioni andine sia come antisettico sia come conservante di derrate alimentari

    Effect of Aqueous Extract of Maca Addition to an Extender for Chilled Canine Semen

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    Antioxidant supplementation has been proposed as a new strategy to improve the long-term preservation of semen. The aim of this study was to evaluate the effect of Maca supplementation of semen extender on quality-related canine semen parameters during cooling. Ejaculates from nine dogs were cooled for 7 days in the absence (control group) or in the presence of 10, 20 and 50 μL/mL of an aqueous extract of Maca. Sperm were evaluated for sperm viability, motility, DNA fragmentation and lipid peroxidation after 3 h, 24 h, 4 days and 7 days of storage. The addition of 10 μL/mL of Maca preserved sperm DNA and plasma membrane integrity at 3 h and increased sperm curvilinear velocity after 24 h. Treatment with 20 and 50 μL/mL of Maca increased the percentage of hyperactivated sperm after 3 h. Moreover, semen treated with 20 μL/mL of Maca decreased lipid peroxidation at 24 h. A significant reduction of sperm DNA and plasma membrane integrity as well as of kinetics parameters between 3 and 24 h of refrigerated storage with the higher concentration tested was observed. Although Maca was not able to protect canine semen with extended refrigeration storage time, it increased hyperactivation and preserved DNA integrity in short-term storage

    Mystery(n) Phenotypic Presentation in Europeans: Report of Three Further Novel Missense RNF213 Variants Leading to Severe Syndromic Forms of Moyamoya Angiopathy and Literature Review

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    Moyamoya angiopathy (MMA) is a rare cerebral vasculopathy in some cases occurring in children. Incidence is higher in East Asia, where the heterozygous p.Arg4810Lys variant in RNF213 (Mysterin) represents the major susceptibility factor. Rare variants in RNF213 have also been found in European MMA patients with incomplete penetrance and are today a recognized susceptibility factor for other cardiovascular disorders, from extracerebral artery stenosis to hypertension. By whole exome sequencing, we identified three rare and previously unreported missense variants of RNF213 in three children with early onset of bilateral MMA, and subsequently extended clinical and radiological investigations to their carrier relatives. Substitutions all involved highly conserved residues clustered in the C-terminal region of RNF213, mainly in the E3 ligase domain. Probands showed a de novo occurring variant, p.Phe4120Leu (family A), a maternally inherited heterozygous variant, p.Ser4118Cys (family B), and a novel heterozygous variant, p.Glu4867Lys, inherited from the mother, in whom it occurred de novo (family C). Patients from families A and C experienced transient hypertransaminasemia and stenosis of extracerebral arteries. Bilateral MMA was present in the proband's carrier grandfather from family B. The proband from family C and her carrier mother both exhibited annular figurate erythema. Our data confirm that rare heterozygous variants in RNF213 cause MMA in Europeans as well as in East Asian populations, suggesting that substitutions close to positions 4118-4122 and 4867 of RNF213 could lead to a syndromic form of MMA showing elevated aminotransferases and extracerebral vascular involvement, with the possible association of peculiar skin manifestations

    Modulation of biliary cancer chemo-resistance through microRNA-mediated rewiring of the expansion of CD133+ cells

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    Changes in single microRNA (MIR) expression have been associated with chemo-resistance in Biliary Tract Cancer (BTC). However, a global assessment of the dynamic role of the microRNome has never been performed to identify potential therapeutic targets that are functionally relevant in the BTC cell response to chemotherapy. APPROACH AND RESULTS: high-throughput-screening of 997 LNA-MIR-inhibitors was performed in 6 CCA cell lines treated with Cisplatin-Gemcitabine (CG) seeking changes in cell viability. Validation experiments were performed with miRvana probes. MIR and gene expression was assessed by TaqMan-assay, RNA-sequencing and in-situ-hybridization in 4 indepedent cohorts of human BTC. Knock-out of microRNA was achieved by CRISPR-CAS9 in CCLP cells (MIR1249KO) and tested for effects on chemotherapy sensitivity in-vitro and in-vivo. High-throughput-screening revealed that MIR1249-inhibition enhanced chemotherapy sensitivity across all cell lines. MIR1249 expression was increased in 41% of cases in human BTC. In validation experiments, MIR1249-inhibition did not alter cell viability in untreated or DMSO-treated cells; however it did increase CG effect. MIR1249 expression was increased in CD133+ biliary cancer cells freshly isolated from the stem niche of human BTC, as well as in CD133+ chemo-resistant CCLP cells. MIR1249 modulated the chemotherapy-induced enrichment of CD133+ cells by controlling their clonal expansion via the Wnt-regulator FZD8. MIR1249KO cells had impaired expansion of the CD133+ subclone and its enrichment after chemotherapy, reduced expression of Cancer-Stem-Cell markers, and increased chemosensitivity. MIR1249KO xenograft BTC models showed tumour shrinkage after exposure to weekly CG, while WT models showed only stable disease over treatment
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