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1.
Brain Sci ; 10(7)2020 Jul 12.
Article in English | MEDLINE | ID: mdl-32664704

ABSTRACT

Children with autism spectrum disorder (ASD) show worse oral health than their peers. Their access to health services is, at present, inadequate: few high-quality interventions have been designed and implemented to improve their care procedures so far. The purpose of this study is to describe an experience of dental care supported by Information and Communication Technologies (ICT), for children with ASD in a public health service. In our study, 59 children (mean age 9.9 years; SD = 5.43) participated in the MyDentist project. It integrates classic dental care techniques with new practices for desensitization and fear control, delivered through an enhanced customized ICT-based intervention aiming at familiarizing the child with ASD with the medical setting and procedures. Two questionnaires were filled out by parents to describe the acceptability of the MyDentist experience for their children. Significant results were shown from T0 (before initiating MyDentist) to T1 (after 6 months of the MyDentist experience) regarding improved oral hygiene and cooperation during dental treatments. Families positively assessed the use of ICT support. In conclusion, the project demonstrated acceptability by parents, suggesting that public health dental care and prevention can be successfully implemented without resorting to costly pharmacological interventions (with potential side effects), taking better care of children's health.

2.
PLoS One ; 10(10): e0141041, 2015.
Article in English | MEDLINE | ID: mdl-26484667

ABSTRACT

In the root apoplasm, V(V) and V(IV) toxicity can be alleviated through redox and complexation reactions involving phenolic substances and the polyuronic components. In such context we report the role of polygalacturonic acid (PGA) on the reducing activity of caffeic acid (CAF) towards V(V). The redox reaction was particularly effective at pH 2.8 leading to the formation of oxidation products with redox activity towards V(V). An o-quinone was identified as the first product of the reaction which is further involved in the formation of CAF dimers. At pH ≥ 3.6 the redox activity decreased and a yield in V(IV) equal to 38, 31, 21 and 14% was found at pH 3.6, 4.0. 5.0 and 6.0 respectively compared with that obtained at pH 2.8. The redox reaction was faster in the presence of PGA and a higher yield of V(IV) was found in the 4.0-6.0 pH range with respect to the CAF-V(V) binary system. The higher efficiency of the redox reaction in the presence of PGA was related with the ability of PGA to bind V(IV). The biological significance of the redox reaction between CAF and V(V), as well as the role of PGA in such reaction, was established "in vivo" using triticale plants. Results showed that PGA reduced significantly the phytotoxic effects of the V(V)-CAF system.


Subject(s)
Environmental Pollutants/toxicity , Pectins/metabolism , Plant Roots/metabolism , Vanadates/metabolism , Vanadates/toxicity , Caffeic Acids/chemistry , Environmental Pollutants/metabolism , Environmental Pollution/adverse effects , Inactivation, Metabolic , Oxidation-Reduction , Plants/drug effects
3.
Plant Physiol Biochem ; 48(12): 1008-14, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20951053

ABSTRACT

In order to better understand the processes that regulate the accumulation in the apoplasm of heavy metals and their mobilization by the plant metabolites it is essential to study the mechanisms that regulate the interactions between metal ions and pectins. In such a context, the sorption of Cd(II), Zn(II), Cu(II) and Pb(II) from single and multi-metal solutions, by a Ca-polygalacturonate gel with a degree of esterification of 18.0 (PGAM(1)) and 65.5% (PGAM(2)) was studied in the 3.0-6.0 pH range in the presence of CaCl(2) 2.5mM. The sorption of Cr(III) from single metal solution was also considered. The results show that the amount of each metal ion sorbed increases with increasing the initial metal ion concentration and pH. The data from the single metal solution tests show that at pH 6.0 the affinity of the metal ions towards the PGAM(1) matrix follows the order: Cr(III)>Cu(II)≅Pb(II)≫Zn(II)≅Cd(II). The simultaneous sorption of the bivalent metal ions by the PGAM(1) gels indicates that Pb(II) is selectively sorbed. The FT-IR spectra show that the carboxylate groups are mainly responsible for the metal ion coordination. The ability of PGAM(2) to accumulate Cr(III), Cu(II), and Pb(II) was lower than that found in the PGAM(1) systems whereas the sorption of Zn(II) and Cd(II) was negligible.


Subject(s)
Metals, Heavy/pharmacokinetics , Pectins/pharmacokinetics , Plant Roots/metabolism , Calcium/metabolism , Cations/pharmacokinetics , Gels , Hydrogen-Ion Concentration , Pectins/metabolism , Plant Roots/chemistry , Solutions
4.
Plant Physiol Biochem ; 47(7): 615-22, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19285877

ABSTRACT

The role of Fe(III) stored at the soil-root interface in the accumulation of arsenate and the influence of citric acid on the As(V) mobility were investigated by using Ca-polygalacturonate networks (PGA). The results indicate that in the 2.5-6.2 pH range Fe(III) interacts with As(V) leading to the sorption of As(V) on Fe(III) precipitates or Fe-As coprecipitates. The FT-IR analysis of these precipitates evidenced that the interaction produces Fe(III)-As(V) inner-sphere complexes with either monodentate or bidentate binuclear attachment of As(V) depending on pH. In the 3.0-6.0 pH range, As(V) diffuses freely through the polysaccharidic matrix that was found to exert a negligible reducing action towards As(V). At pH 6.0 citric acid is able to mobilize arsenate from the As-Fe-PGA network through the complexation of the Fe(III) polyions that leads to the release of As(V).


Subject(s)
Arsenates/pharmacokinetics , Citric Acid/metabolism , Ferric Compounds/metabolism , Pectins/metabolism , Adsorption , Arsenites/pharmacokinetics , Calcium/chemistry , Hydrogen-Ion Concentration , Plant Roots/metabolism , Soil
5.
Plant Physiol Biochem ; 46(4): 435-43, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18362075

ABSTRACT

With the aim to verify if Fe(III) ions accumulated in a network of Ca-polygalacturonate (PGA) may promote the oxidation of caffeic acid (CAF) the interaction at pH 5.0 between CAF and Fe(III) ions trapped in a PGA was studied. The sorption kinetics evidenced a great affinity of CAF towards the Fe-PGA matrix. Chromatographic tests showed that the interaction leads to the formation of products which can be considered as CAF oligomers characterized by FT-IR spectra similar to those of natural humic acids. Tests carried out under nitrogen suggest that at pH 5.0 oxygen does not affect the nature of these oxidation products. Oxygen was hypothesized to exert a direct action on the redox process by oxidizing the Fe(II) ions, produced by oxidation of CAF, to Fe(III) thus regenerating oxidizing sites. A possible mechanism of formation of the polymers was proposed that implies that the CAF oxidation leads to highly reactive species such as semiquinones which give rise, by an oxidative coupling reaction, to the formation of oligomers that can aggregate through secondary bonds to produce more complex structures as those that characterize humic acids.


Subject(s)
Benzoquinones/chemistry , Caffeic Acids/chemistry , Iron/chemistry , Oxygen/chemistry , Pectins/chemistry , Cations/chemistry , Humic Substances , Hydrogen-Ion Concentration , Oxidation-Reduction
6.
Plant Physiol Biochem ; 45(5): 341-9, 2007 May.
Article in English | MEDLINE | ID: mdl-17481911

ABSTRACT

With the aim to investigate the role of the polyuronic components in the accumulation of iron and phosphate at the soil-root interface, the interactions of Ca-polygalacturonates (PGAs) with Fe(III) and P ions and of Fe(III)-Ca-polygalacturonates (Fe-PGAs) with P ions were studied at pH 4.7. The role of citric, malic and pyruvic acids in the mobilization of Fe(III) and P, in the presence and absence of Ca(II) 2.5mM, was also investigated. The sorption kinetics evidenced that P diffuses freely through the calcium polysaccharidic matrix whereas Fe(III) accumulates as an hydroxypolymer. The sorption kinetics of P by the Fe-PGA indicated that the amount of P sorbed increases with increasing its initial concentration up to a constant value equal to 0.98micromol/3.87micromolmg(-1) of Fe(III)-polymer trapped. The FT-IR spectra of the P-Fe-PGA systems, show bands attributable to P-O(H) stretching vibrations. The study of systems with a constant initial P amount and varying Fe(III) amounts allowed to hypothesize that phosphate settles down inside holes formed by the carboxylate groups of galacturonic units. Citric and malic acids showed to be active in the mobilization of both Fe and P whereas pyruvic acid appeared inactive.


Subject(s)
Iron/metabolism , Phosphates/metabolism , Plant Roots/metabolism , Soil/analysis , Uronic Acids/metabolism , Carbohydrate Conformation , Citric Acid/chemistry , Iron/chemistry , Kinetics , Malates/chemistry , Pectins/chemistry , Phosphates/chemistry , Pyruvic Acid/chemistry , Time Factors
7.
Chemosphere ; 67(10): 1919-26, 2007 May.
Article in English | MEDLINE | ID: mdl-17240421

ABSTRACT

In the soil-plant system, the Cr(VI) toxicity can be moderated through redox reactions involving phenolic substances. In such a context, we report the reducing activity of caffeic acid (CAF) towards Cr(VI) in aqueous phase. The redox reaction between Cr(VI) and CAF was studied as a function of both time and pH at different initial metal concentrations. The reaction was particularly effective at pH 2.5. The kinetic data indicate that the reaction proceeds through two steps: the first is faster and involves four electrons, the latter, which is slower, five electrons. The chromatograms evidence the formation of oxidation products (OP) with a different redox activity towards Cr(VI). A yield of Cr(III) equal to that obtained at pH 2.5 and pH 3.1 in about 7 and 25 h, respectively, was reached at pH 4.2 only after a much longer reaction time (50h). At pH>4.2 the reaction occurred even more slowly, and its kinetic trend was more and more difficult to study at pH values higher than 5.0 due to the formation of precipitates. Other phenolics investigated (o-, m-, p-coumaric acids) showed a reducing activity negligible compared to that of CAF: about 30% of p-coumaric acid was oxidized at pH 2.5 only after two months of reaction.


Subject(s)
Caffeic Acids/chemistry , Chromium/analysis , Soil Pollutants/analysis , Biodegradation, Environmental , Chromium/chemistry , Hydrogen-Ion Concentration , Models, Chemical , Oxidation-Reduction , Soil Pollutants/chemistry , Time Factors
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