15 research outputs found
Correction: Differences between experimental and placebo arms in manual therapy trials: a methodological review (BMC Medical Research Methodology, (2022), 22, 1, (219), 10.1186/s12874-022-01704-8)
No full textFollowing publication of the original article [1], the authors reported an error in the presentation of author names. The given name and family name were swapped. The correct author names are as follows: Giandomenico D’Alessandro, Nuria Ruffini, Alessandro Aquino, Matteo Galli, Mattia Innocenti, Marco Tramontano, Francesco Cerritelli. The author group has been updated above and the original article [1] has been corrected
Alkylation of carbonyl compounds in water: formation of C-C and C-O bonds in the presence of surfactants
No full textAn effective simulation of aqueous micellar aggregates by computational models
No full textWe have computationally studied the interaction modes, localization and orientation of a benzene (Bz) molecule on the surface of micelles formed by cetyltrimethylammonium salts CTAX. Experimental H-1-NMR data on complexation shifts induced by Bz on the polar head hydrogens and on the adjacent methylene hydrogens of CTAX have been interpreted using a computational approach that combines an automatic molecular docking procedure with a calculation module that accounts for NMR complexation shifts due to ring current diamagnetic anisotropy. Three different models were used to reduce the complexity of the micellar system. Computational results, in good agreement with available experimental data, point to a preferential localization of the Bz molecule along the CTAX alkyl tail, about 3.9 angstrom away from the charged nitrogen. The Bz molecular plane is predicted perpendicular to the C-H bonds of the alkyl tail. The good results obtained with the simplest model suggest that it could be used to study more complex systems involving surfactants endowed with molecular recognition or catalytic abilities
Supramolecular Assemblies as Promoters of Iodohydrin Formation
No full textFinding alternative reaction media to replace polluting organic solvents is one aim of green chemistry. The ultimate green solvent, water, is the cheapest, non-toxic and most readily available reaction medium: three properties which make it an environmentally and economically attractive solvent. However, a fundamental problem in performing reactions in water is that many organic substrates are hydrophobic and not soluble in water. Several approaches are possible in solubilizing these compounds in aqueous media, one of which is carrying out reactions in aqueous solutions of surfactants at concentrations above their critical micellar concentration (cmc). Reactions of iodine with cyclohexene, 1-octene and styrene in water or in the presence of cationic surfactants do not give useful amounts of iodohydrins, but reactions in anionic surfactants give good yields. Iodohydrins are important functionalizable compounds and are readily prepared in the presence of sodium dodecyl sulfate (SDS) or sodium N-dodecanoyl sarcosinate (SANa). The critical conditions for these reactions were optimized with a rigorous statistical approach, the experimental design method. Use of these newly optimized reaction conditions gave high yields in short times for all of the alkenes examined. The use of anionic surfactants in water to form iodohydrins is a valid alternative to methods previously described
Alkylation of carbonyl compounds in water: formation of C-C and C-O bonds in the presence of surfactants
No full textThe formation of C[BOND]C and C[BOND]O bonds by the reaction of enolate intermediates with electrophilic substrates commonly requires strong bases, aprotic solvents and very low temperatures. A way of performing the same reactions with sodium hydroxide at moderate temperatures in aqueous surfactant solutions is presented. Different halides, ketones and surfactants (cationic, zwitterionic and anionic) have been used. The results obtained show that the amount of ketone alkylation is much higher and that the reactions are faster in the presence than in the absence of surfactant aggregates. The hydrolysis of the halide is minimised in the presence of cationic or zwitterionic surfactants
Breakdown kinetics of aggregates from poly(ethylene glycol-bl-propylene sulfide) di- and triblock copolymers induced by a non-ionic surfactant
No full textWe explored the effects of addition of the nonionic surfactant Triton X-100 on the stability of aggregates of poly(ethylene glycol-bl-propylene sulfide) di- and triblock copolymers. Fluorescence spectra of pyrene, used as a probe molecule, elucidated the various stages of transformation from pure copolymeric micelles to surfactant-rich micelles. Turbidity measurements yielded insight into the mechanism of the interaction, the hydrophobicity of the copolymer driving the process. Triton X-100 tends to strongly interact with highly hydrophobic copolymers by inserting into the core of the micellar aggregates. On the other hand, Triton X-100 tends to interact with the corona of micelles formed by less hydrophobic copolymers which, for this reason, are more stable upon addition of this destabilizing agent. Kinetic data give evidence that only monomers, not micelles of surfactant, interact with the copolymer micelles. (C) 2008 Wiley Periodicals, Inc.LMR
Sulle tracce del segno scritti di Alberto Veca anni settanta - duemila ; Mario Benedetti, Irma Blank, Eros, Bonamini, Carlo Bonfà, Giovanni Campus, Loriana Castano, Alberto Cavalieri, Carlo Cioni, Dadamaino, Claudio D'Angelo, Sandro De Alexandris, Fernanda Fedi, Maria Cristina Galli, Gino Gini, Gino Gorza, Vincentiu Grigorescu, Maria Luisa Grimani, Cosimo Lerose, Marco Magrini, Lucia Pescador, Elisabeth Scherffig, Guido Strazza, Nanni Varale, Simona Weller
No full textAggregation Behavior of Poly(ethylene glycol-bl-propylene sulfide) Di- and Triblock Copolymers in Aqueous Solution
No full textBlock copolymers of poly(ethylene glycol)-bl-poly(propylene sulfide) (PEG-PPS) have recently emerged as a new macromolecular amphiphile capable of forming a wide range of morphologies when dispersed in water. To understand better the relationship between stability and morphology in terms of the relative and absolute block compositions, we have synthesized a collection of PEG-PPS block copolymers and quantified their critical aggregation concentration and observed their morphology using cryogenic transmission electron microscopy after thin film hydration with extrusion and after solvent dispersion from tetrahydrofuran, a solvent for both blocks. By understanding the relationship between aggregate character and block copolymer architecture, we have observed that whereas the relative block lengths control morphology, the stability of the aggregates upon dilution is determined by the absolute block length of the hydrophobic PPS block. We have compared results obtained with PEG-BPS to those obtained with poly(ethylene glycol)-bl-poly(propylene oxide)-bl-poly(ethylene glycol) block copolymers (Pluronics). The results reveal that the PEG-PPS aggregates are substantially more stable than Pluronic aggregates, by more than an order of magnitude. PEG-PPS can form a wide variety of stable or metastable morphologies in dilute solution within normal time and temperature ranges, whereas Pluronics can generally form only spherical micelles under the same conditions. On the basis of these results, block copolymers of PEG with poly(propylene sulfide) may present distinct advantages over those with poly(propylene glycol) for a number of applications.LMR
Data_Sheet_1_The Neonatal Assessment Manual scorE: A Reliability Study on Hospitalized Neonates.docx
No full textDespite clinical improvements in neonatal intensive care units (NICUs), prematurity keeps causing several comorbidities. To enhance the management of such conditions, in previous studies we devised the Neonatal Assessment Manual scorE (NAME) model, a structured touch-based assessment that aims to evaluate how newborns respond to gentle touch-based stimuli. The present study aimed to begin assessing the NAME interrater reliability and specific agreements. At the “Vittore Buzzi” Pediatric Hospital NICU ward in Milan, Italy, we enrolled 144 newborns, 85 male and 59 female, with a mean age of 35.9 weeks (±4.1) and a weight of 2,055.3 g (±750.6). Two experienced manual professionals performed the NAME procedure on all the infants. Regarding the total sample and the analysis by sex, we found moderate and statistically significant results for the interrater reliability (p < 0.001) and the specific agreements (p < 0.05), in particular for the “Marginal” score. Furthermore, interrater reliability significantly (p < 0.05) increased as age and weight increased, whereas there was an almost constant moderate and significant (p < 0.05) agreement especially for the “Marginal” score. Therefore, we found preliminary results showing that the NAME could be a reliable diagnostic tool for assessing the newborns' general condition.</p
Data_Sheet_1_Newborns' clinical conditions are correlated with the neonatal assessment manual scorE (NAME).PDF
No full textObjectiveTo investigate the relationship between the Neonatal Assessment Manual scorE (NAME) and newborns' clinical condition on a large number of infants. The NAME model was developed as an instrument to assess the infant's general conditions, especially in NICUs, by evaluating how the infant's body responds to an external stressor such as static touch. Previous studies, employing experienced assessors, showed good validity indices as well as high inter-rater reliability.Study designNewborns were recruited at the “Vittore Buzzi” Pediatric Hospital NICU ward in Milan and their clinical conditions were collected through a standardized form—the complexity index. Two manual practitioners assessed all eligible newborns using the NAME scores. Data was analyzed using Kendall's τ correlation and odds ratio (OR) to assess the relationship between the NAME scores and the complexity index.ResultsTwo hundred two newborns (46% female; 34.1 w ± 4.3; birth weight of 2,093.4 gr ± 879.8) entered the study. The Kendall's correlation between the clinical conditions (complexity index) and the NAME score was −0.206 [95% CI: (−0.292, −0.116), p-value ConclusionThe present paper adds evidence to the NAME model validity by demonstrating its applicability in the clinical neonatological context.</p
