Sapienza University of Rome

About: Sapienza University of Rome is a education organization based out in Rome, Lazio, Italy. It is known for research contribution in the topics: Population & Medicine. The organization has 62002 authors who have published 155468 publications receiving 4397244 citations. The organization is also known as: La Sapienza & Università La Sapienza di Roma.

The acquisition and development of language by bilingual children

Abstract: Analysing the gradual learning process through which a child becomes bilingual from early infancy, three stages can be distinguished: (1) the child has one lexical system which includes words from both languages; (2) the child distinguishes two different lexicons but applies the same syntactic rules to both languages; (3) the child has two linguistic codes, differentiated both in lexicon and in syntax, but each language is exclusively associated with the person using that language. Only at the end of this stage, when the tendency to categorize people in terms of their language decreases, can one say that a child is truly bilingual.

Effect of Conservative vs Conventional Oxygen Therapy on Mortality Among Patients in an Intensive Care Unit: The Oxygen-ICU Randomized Clinical Trial

Abstract: Importance Despite suggestions of potential harm from unnecessary oxygen therapy, critically ill patients spend substantial periods in a hyperoxemic state. A strategy of controlled arterial oxygenation is thus rational but has not been validated in clinical practice. Objective To assess whether a conservative protocol for oxygen supplementation could improve outcomes in patients admitted to intensive care units (ICUs). Design, Setting, and Patients Oxygen-ICU was a single-center, open-label, randomized clinical trial conducted from March 2010 to October 2012 that included all adults admitted with an expected length of stay of 72 hours or longer to the medical-surgical ICU of Modena University Hospital, Italy. The originally planned sample size was 660 patients, but the study was stopped early due to difficulties in enrollment after inclusion of 480 patients. Interventions Patients were randomly assigned to receive oxygen therapy to maintain Pao 2 between 70 and 100 mm Hg or arterial oxyhemoglobin saturation (Spo 2 ) between 94% and 98% (conservative group) or, according to standard ICU practice, to allow Pao 2 values up to 150 mm Hg or Spo 2 values between 97% and 100% (conventional control group). Main Outcomes and Measures The primary outcome was ICU mortality. Secondary outcomes included occurrence of new organ failure and infection 48 hours or more after ICU admission. Results A total of 434 patients (median age, 64 years; 188 [43.3%] women) received conventional (n = 218) or conservative (n = 216) oxygen therapy and were included in the modified intent-to-treat analysis. Daily time-weighted Pao 2 averages during the ICU stay were significantly higher ( P 2 , 102 mm Hg [interquartile range, 88-116]) vs the conservative group (median Pao 2 , 87 mm Hg [interquartile range, 79-97]). Twenty-five patients in the conservative oxygen therapy group (11.6%) and 44 in the conventional oxygen therapy group (20.2%) died during their ICU stay (absolute risk reduction [ARR], 0.086 [95% CI, 0.017-0.150]; relative risk [RR], 0.57 [95% CI, 0.37-0.90]; P = .01). Occurrences were lower in the conservative oxygen therapy group for new shock episode (ARR, 0.068 [95% CI, 0.020-0.120]; RR, 0.35 [95% CI, 0.16-0.75]; P = .006) or liver failure (ARR, 0.046 [95% CI, 0.008-0.088]; RR, 0.29 [95% CI, 0.10-0.82]; P = .02) and new bloodstream infection (ARR, 0.05 [95% CI, 0.00-0.09]; RR, 0.50 [95% CI, 0.25-0.998; P = .049). Conclusions and Relevance Among critically ill patients with an ICU length of stay of 72 hours or longer, a conservative protocol for oxygen therapy vs conventional therapy resulted in lower ICU mortality. These preliminary findings were based on unplanned early termination of the trial, and a larger multicenter trial is needed to evaluate the potential benefit of this approach. Trial Registration clinicaltrials.gov Identifier:NCT01319643

IL-10 prevents the differentiation of monocytes to dendritic cells but promotes their maturation to macrophages.

Abstract: Human monocytes cultured with granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-13 for 7 days differentiate into cells with the morphology and function of dendritic cells (DC). We have investigated the effect of IL-10 on this differentiation pathway. In the presence of IL-10 cells did not develop DC morphology, did not express CD1a and had lower levels of MHC class II. IL-10 promoted the differentiation of large cells with the morphology, cytochemistry and membrane phenotype of macrophages, including staining for nonspecific esterase and high levels of CD14, CD16 and CD68. The effect of IL-10 was dose dependent and was best appreciated when the cytokine was added at the initiation of the culture, as addition on day 3 was less inhibitory. When added to already differentiated DC on day 6, IL-10 caused only a modest reduction of MHC class II and CD1a expression, and no acquisition of the macrophage markers CD14, CD16 and CD68. Prolonged incubation up to 5 days with IL-10 did not induce a shift of differentiated DC to macrophages. On the other hand, the macrophages obtained by culturing for 7 days with GM-CSF+IL-13+IL-10 did not shift to DC upon removal of IL-10 for up to 3 days. Thus, the effect of IL-10 on monocyte differentiation, occurs only at the precursor level and confers an irreversible phenotype. From a functional point of view, cells cultured in the presence of IL-10 were poor stimulators of allogeneic cord blood T cells in mixed lymphocyte reaction (MLR) and presented tetanus toxin (TT) to specific T cell lines with much less efficiency than control DC. In contrast, IL-10-cultured DC showed 7 times greater endocytosis of FITC-dextran. This increased endocytosis was mostly mediated via the mannose receptor, as demonstrated by blocking with unlabeled mannose. In conclusion, IL-10 inhibits DC differentiation from monocytes and, in a substantial proportion of the cells, promotes the differentiation to mature macrophages. Intriguingly, IL-10 inhibits antigen presentation while it stimulates endocytic activity.

Generation of GTP-bound Ran by RCC1 is required for chromatin-induced mitotic spindle formation

Abstract: Chromosomes are segregated by two antiparallel arrays of microtubules arranged to form the spindle apparatus. During cell division, the nucleation of cytosolic microtubules is prevented and spindle microtubules nucleate from centrosomes (in mitotic animal cells) or around chromosomes (in plants and some meiotic cells). The molecular mechanism by which chromosomes induce local microtubule nucleation in the absence of centrosomes is unknown, but it can be studied by adding chromatin beads to Xenopus egg extracts. The beads nucleate microtubules that eventually reorganize into a bipolar spindle. RCC1, the guanine-nucleotide-exchange factor for the GTPase protein Ran, is a component of chromatin. Using the chromatin bead assay, we show here that the activity of chromosome-associated RCC1 protein is required for spindle formation. Ran itself, when in the GTP-bound state (Ran-GTP), induces microtubule nucleation and spindle-like structures in M-phase extract. We propose that RCC1 generates a high local concentration of Ran-GTP around chromatin which in turn induces the local nucleation of microtubules.