225 research outputs found
Distribuzione spaziale dei popolamenti a <i>Lithophyllum byssoides</i>, a <i>Patella ferruginea</i> e della frangia a <i>Cystoseira</i> sp. nell'Arcipelago di La Maddalena (Sardegna-Italia) = Spatial distribution of <i>Lithophyllum byssoides</i>, <i>Patella ferruginea</i> assemblage and <i>Cystoseira</i> sp. fringe in The Maddalena Archipelago (Sardinia-Italy)
A study on the distribution of Lithophyllum byssoides, Patella ferruginea and Cystoseira sp. fringe populations, has been carried out in the national Park of the La Maddalena archipelago. Those species has been protected from international conventions as rare species in danger of extinction. The results of the study shows a good conservation state of the examined islands
Functional neural architecture of cognitive control mediates the relationship between individual differences in bilingual experience and behaviour
Bilinguals have often, but not always, been found to outperform monolinguals on domain-general attentional control. Inconsistent findings have been argued to stem, at least partly, from treating bilingualism as a uniform category and from not considering how neural adaptations to bilingual experiences modulate behavioural outcomes. The present study investigated how patterns of language experience, including language switching behaviour, duration and intensity/diversity of bilingual language use, influence the brain processes underlying cognitive control, and how these in turn translate to cognitive control performance. We examined reaction times and spectral dynamics of the electroencephalograms (EEG) of two-hundred-and-thirty-nine participants (about 70% bilinguals) with diverse language experiences during two cognitive control paradigms testing interference suppression (flanker and Simon task). Using structural equation modelling, we found that different bilingual experience factors were related with neurocognitive measures, which in turn were related with behavioural interference effects, for the flanker but not the Simon task. More specifically, increased frequency of language switching and intensity/diversity of bilingual language usage was negatively related to induced top-down control measures (especially midline-frontal theta), which in turn was beneficial for interference control. In contrast, duration of bilingual engagement correlated negatively with evoked bottom-up control measures (especially P3) and was therefore detrimental to interference control. We demonstrate here for the first time how the different factors of bilingual experience lead to different neural adaptations which impact behavioural outcomes. Significance statement Like other intensive experiences, bilingualism leads to brain adaptations. It results in structural changes in language areas, and, due to demands on language control, in brain areas associated with domain-general cognitive control. Related to this, bilinguals often outperform monolinguals on cognitive control tasks. But what is often ignored is that bilingualism is a multi-dimensional phenomenon, with variations such as diversity of language usage and duration of language use. The present large-scale study of neural functioning in bilingualism revealed for the first time how individual differences in bilingual experience lead to adaptations to brain functioning which in turn affect cognitive control behaviour. It exemplifies how the complexity of individual experiences plays a fundamental role in brain function
Caratterizzazione fisiografica, geomorfologica e bionomica della <i>Rias</i> di Santa Teresa di Gallura: Sardegna nord-orientale = Physiographic, geomorphological and bionomic characterization of the Santa Teresa di Gallura <i>Rias</i> (N.E. Sardinia)
An underwater survey in the Rias of S. Teresa di Gallura was made to characterize the benthic environment by integrating three methods: Side Scan Sonar, ROV, SCUBA diving. The main bionomic features at different depths were described and mapped. The presence of Savalia savaglia, a rare Mediterranean species contributed to enhance the environmental value of the study area
Safety of Induced Sputum Collection in Children Hospitalized With Severe or Very Severe Pneumonia.
Background.: Induced sputum (IS) may provide diagnostic information about the etiology of pneumonia. The safety of this procedure across a heterogeneous population with severe pneumonia in low- and middle-income countries has not been described.
Methods.: IS specimens were obtained as part a 7-country study of the etiology of severe and very severe pneumonia in hospitalized childrenbefore, during, and after the procedure to record oxygen requirement, oxygen saturation, respiratory rate, consciousness level, and other evidence of clinical deterioration. Criteria for IS contraindications were predefined and serious adverse events (SAEs) were reported to ethics committees and a central safety monitor.
Results.: A total of 4653 IS procedures were done among 3802 children. Thirteen SAEs were reported in relation to collection of IS, or 0.34% of children with at least 1 IS specimen collected (95% confidence interval, 0.15%-0.53%). A drop in oxygen saturation that required supplemental oxygen was the most common SAE. One child died after feeding was reinitiated 2 hours after undergoing sputum induction; this death was categorized as possibly related to the procedure.
Conclusions.: The overall frequency of SAEs was very low, and the nature of most SAEs was manageable, demonstrating a low-risk safety profile for IS collection even among severely ill children in low-income-country settings. Healthcare providers should monitor oxygen saturation and requirements during and after IS collection, and assess patients prior to reinitiating feeding after the IS procedure, to ensure patient safety
Influence of Hashimoto thyroiditis on the development of thyroid nodules and cancer in children and adolescents
It is unclear whether patients with Hashimoto thyroiditis (HT) are predisposed to develop thyroid nodules and/or thyroid cancer. The objective of our study was therefore to assess the prevalence of thyroid nodules and/or cancer in patients with HT and to look for possible prognostic factors. A retrospective survey of 904 children/adolescents with HT (709 females, 195 males) regularly followed in nine Italian centers of pediatric endocrinology was performed. Median period of follow-up was 4.5 years (1.2 to 12.8 years). We evaluated free T4, TSH, thyroid peroxidase antibody (TPOAb), thyroglobulin antibodies, and thyroid ultrasound yearly. One hundred seventy-four nodules were detected, with an annual incidence rate of 3.5%. Ten nodules were malignant (8 papillary and 2 papillary follicular variant), giving a 5.7% prevalence of cancer among patients with nodules. The severity of hypo-echogenity at ultrasound, TPOAb, and free T4 serum concentrations were predictive for the appearance of new nodules. Furthermore, a positive correlation was observed between TPOAb titer and the development of thyroid cancer. In conclusion, HT seems to influence the development of thyroid nodules, but not cancer in children and adolescents
Kinetochore Microtubule Dynamics and Attachment Stability Are Regulated by Hec1
Mitotic cells face the challenging tasks of linking kinetochores to growing and shortening microtubules and actively regulating these dynamic attachments to produce accurate chromosome segregation. We report here that Ndc80/Hec1 functions in regulating kinetochore microtubule plus-end dynamics and attachment stability. Microinjection of an antibody to the N terminus of Hec1 suppresses both microtubule detachment and microtubule plus-end polymerization and depolymerization at kinetochores of PtK1 cells. Centromeres become hyperstretched, kinetochore fibers shorten from spindle poles, kinetochore microtubule attachment errors increase, and chromosomes severely mis-segregate. The N terminus of Hec1 is phosphorylated by Aurora B kinase in vitro, and cells expressing N-terminal nonphosphorylatable mutants of Hec1 exhibit an increase in merotelic attachments, hyperstretching of centromeres, and errors in chromosome segregation. These findings reveal a key role for the Hec1 N terminus in controlling dynamic behavior of kinetochore microtubules
Rhinosinusal polyposis and metals: morphological aspects
Metals have strong toxic effects in humans and can act as immunoregulatory factors. The purpose of our study was to determine whether the concentrations of metals are associated with the clinical course of nasal polyposis (NP). We measured the concentrations of 10 metals (Zn, Mn, Se, Fe, Cr, Ni, Pb, Al, Cd, and Cu) in 58 patients with NP, and 29 controls with a healthy nasal mucosa. We used electron microscopy to compare the ultrastructural features of the nasal mucosa between NP patients and healthy controls. Concentrations of metals in nasal polyps and healthy mucosa were determined by mass spectrometry. Transmission electron microscopic (TEM) and scanning electron microscopic (SEM) images of the nasal mucosa were obtained. The mean tissue concentrations of all 10 metals were significantly lower in NP patients than in healthy controls (P < 0.001). Tissue concentrations of each metal were lower in stages III and IV NP than in stages I and II NP, although the differences were not statistically significant. TEM and SEM revealed changes in the mucosal ultrastructure in NP with progression from isolated polyposis (stages I and II) to massive polyposis (stages III and IV) with progressive fibrosis, devascularisation, and inflammation. Tissue concentrations of metals were lower in NP patients than in healthy controls, and this was particularly evident in massive polyposis. Polyp structure could contribute to the lower concentrations of metals by exposing the tissue to increased oxidative stress
Evidence that Aurora B is implicated in spindle checkpoint signalling independently of error correction
Aurora B kinase corrects aberrant microtubule-chromosome attachments during mitosis. This function derives from Aurora B's role in the spindle assembly checkpoint, independently of its established role in the tension dependent microtubule-chromosome error correction mechanism
Novel styryl-indoles as small molecule inhibitors of 25-hydroxyvitamin D-24-hydroxylase (CYP24A1): Synthesis and biological evaluation
The synthesis of a series of imidazole styrylindoles and sulfonyl styrylindoles derivatives is described. Evaluation of binding affinity and inhibitory activity against CYP24A1 identified the imidazole styrylindoles as potent inhibitors with activity greater or comparable with the standard ketoconazole. Flexible alignment and docking studies of the inhibitors in the CYP24A1 enzyme active site confirmed that complete occupation of the vitamin D access tunnel is essential to inhibitory activity, allowing exposure to multiple hydrophobic binding interactions and optimal conformation for the interaction of the imidazole nitrogen lone pair and the active site haem
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