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1.
Inorg Chem ; 63(29): 13636-13643, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38984766

RESUMO

In this contribution, we describe the preparation, by means of a precipitation reaction from aqueous solution at 40 °C, and the structural characterization of nanocrystalline powders of trigonal Tb1-xEuxPO4·nH2O (with x = 0, 0.005, 0.01, 0.05, and 0.1; n tentatively assigned as 0.67) which crystallize in the two possible P3121 or P3221 enantiomorphic space groups. While the volume of the crystal lattice is not significantly affected by the Tb3+/Eu3+ substitution, the average crystallite size seems to depend on the Eu3+ dopant concentration and ranges from 13 to 30 nm. The desired handedness of the crystals has been induced by using, during the synthesis, one of the two possible enantiomers of tartaric acid (l or d). The analysis of the luminescence excitation and emission spectra, together with the decay kinetics of the 5D4 Tb3+ excited state, suggests the presence of a very efficient Tb3+ → Eu3+ energy transfer process in the Eu3+-doped orthophosphates. Upon excitation of Tb3+ ions at 368 nm, the enantiomorphic powders grown with l- or d-tartaric acid (i.e., l-TbPO4·0.67H2O/d-TbPO4·0.67H2O, l-Tb0.995Eu0.005PO4·0.67H2O/d-Tb0.995Eu0.005PO4·0.67H2O, and l-Tb0.9Eu0.1PO4·0.67H2O/d-Tb0.9Eu0.1PO4·0.67H2O) exhibited mirror circularly polarized luminescence signals in the visible spectral region (in the green and/or in the red).

2.
Int J Mol Sci ; 25(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38256278

RESUMO

Extracellular vesicles (EVs), comprising exosomes and microvesicles, are small membranous structures secreted by nearly all cell types. They have emerged as crucial mediators in intercellular communication, playing pivotal roles in diverse physiological and pathological processes, notably within the realm of immunity. These roles go beyond mere cellular interactions, as extracellular vesicles stand as versatile and dynamic components of immune regulation, impacting both innate and adaptive immunity. Their multifaceted involvement includes immune cell activation, antigen presentation, and immunomodulation, emphasising their significance in maintaining immune homeostasis and contributing to the pathogenesis of immune-related disorders. Extracellular vesicles participate in immunomodulation by delivering a wide array of bioactive molecules, including proteins, lipids, and nucleic acids, thereby influencing gene expression in target cells. This manuscript presents a comprehensive review that encompasses in vitro and in vivo studies aimed at elucidating the mechanisms through which EVs modulate human immunity. Understanding the intricate interplay between extracellular vesicles and immunity is imperative for unveiling novel therapeutic targets and diagnostic tools applicable to various immunological disorders, including autoimmune diseases, infectious diseases, and cancer. Furthermore, recognising the potential of EVs as versatile drug delivery vehicles holds significant promise for the future of immunotherapies.


Assuntos
Micropartículas Derivadas de Células , Exossomos , Vesículas Extracelulares , Humanos , Imunidade Adaptativa , Comunicação Celular
3.
Int J Mol Sci ; 25(14)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39063030

RESUMO

Chemical pollution poses a significant threat to human health, with detrimental effects on various physiological systems, including the respiratory, cardiovascular, mental, and perinatal domains. While the impact of pollution on these systems has been extensively studied, the intricate relationship between chemical pollution and immunity remains a critical area of investigation. The focus of this study is to elucidate the relationship between chemical pollution and human immunity. To accomplish this task, this study presents a comprehensive review that encompasses in vitro, ex vivo, and in vivo studies, shedding light on the ways in which chemical pollution can modulate human immunity. Our aim is to unveil the complex mechanisms by which environmental contaminants compromise the delicate balance of the body's defense systems going beyond the well-established associations with defense systems and delving into the less-explored link between chemical exposure and various immune disorders, adding urgency to our understanding of the underlying mechanisms and their implications for public health.


Assuntos
Poluição Ambiental , Humanos , Poluição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Exposição Ambiental/efeitos adversos , Imunidade/efeitos dos fármacos , Sistema Imunitário/efeitos dos fármacos , Animais
4.
Epidemiol Prev ; 48(3): 210-219, 2024.
Artigo em Italiano | MEDLINE | ID: mdl-38995134

RESUMO

OBJECTIVES: to evaluate the risk profile of hypospadias in Gela, an Italian National Priority Contaminated Site (NPCS) located in Sicily Region (Southern Italy), characterized by a significant excess of hypospadias in newborn residents compared to data from reference on regional, national, and international basis and, until 2014, by the presence of a petrochemical plant. DESIGN: geographical analyses were conducted by comparing the prevalence of the Gela municipality to prevalence found in Sicily, in a territorial area bordering Gela (ALG), and in the NPCSs of Milazzo and Priolo. The geographical comparisons were conducted for the period 2010-2020, the trend within the Gela NPCS was evaluated by comparing two subperiods (2010-2014 and 2015-2020). SETTING AND PARTICIPANTS: children up to 1 year of age with hypospadias resident in the municipality of Gela in the period 2010-2020. MAIN OUTCOMES MEASURES: crude odds ratios (OR) and respective 95% confidence intervals (95%CI) were used to compare the prevalence observed in Gela and that detected in the comparison areas. RESULTS: excess risk for hypospadias was highlighted in 2010-2020 in Gela vs Sicily (OR 4.45; 95%CI 3.45-5.75), vs ALG (OR 4.29; 95%CI 3.02-6.10), and vs the NPCSs of Milazzo (OR 2.32; 95%CI 1.32-4.07) and Priolo (OR 2.37; 95%CI 1.55-3.62). The between-period comparisons in Gela did not show an important difference between 2010-2014 and 2015-2020 (OR 1.37; 95%CI 0.83-2.24), with a prevalence of 98.9 and 72.4 per 10,000, respectively. CONCLUSIONS: the prevalence of hypospadias in 2015-2020 remains very high, although decreasing when compared to 2010-2014 period. The Gela data, despite the refinery being closed after 2014, suggest a complex situation in which multiple risk factors may play a role.


Assuntos
Hipospadia , Humanos , Hipospadia/epidemiologia , Prevalência , Masculino , Sicília/epidemiologia , Lactente , Recém-Nascido , Itália/epidemiologia , Indústria de Petróleo e Gás , Exposição Ambiental/efeitos adversos , Fatores de Risco , Razão de Chances
5.
Inorg Chem ; 62(23): 8812-8822, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37262334

RESUMO

The complexes [Eu(bpcd)(tta)], [Eu(bpcd)(Coum)], and [Tb(bpcd)(Coum)] [tta = 2-thenoyltrifluoroacetyl-acetonate, Coum = 3-acetyl-4-hydroxy-coumarin, and bpcd = N,N'-bis(2-pyridylmethyl)-trans-1,2-diaminocyclohexane-N,N'-diacetate] have been synthesized and characterized from photophysical and thermodynamic points of view. The optical and chiroptical properties of these complexes, such as the total luminescence, decay curves of the Ln(III) luminescence, electronic circular dichroism, and circularly polarized luminescence, have been investigated. Interestingly, the number of coordinated solvent (methanol) molecules is sensitive to the nature of the metal ion. This number, estimated by spectroscopy, is >1 for Eu(III)-based complexes and <1 for Tb(III)-based complexes. A possible explanation for this behavior is provided via the study of the minimum energy structure obtained by density functional theory (DFT) calculations on the model complexes of the diamagnetic Y(III) and La(III) counterparts [Y(bpcd)(tta)], [Y(bpcd)(Coum)], and [La(bpcd)(Coum)]. By time-dependent DFT calculations, estimation of donor-acceptor (D-A) distances and of the energy position of the S1 and T1 ligand excited states involved in the antenna effect was possible. These data are useful for rationalizing the different sensitization efficiencies (ηsens) of the antennae toward Eu(III) and Tb(III). The tta ligand is an optimal antenna for sensitizing Eu(III) luminescence, while the Coum ligand sensitizes better Tb(III) luminescence {ϕovl = 55%; ηsens ≥ 55% for the [Tb(bpcd)(Coum)] complex}. Finally, for the [Eu(bpcd)(tta)] complex, a sizable value of glum (0.26) and a good quantum yield (26%) were measured.

6.
Molecules ; 28(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36903496

RESUMO

In this contribution, we present the spectroscopic study of two NIR emitting hydrophobic heteroleptic (R,R)-YbL1(tta) and (R,R)-NdL1(tta) complexes (with tta = 2-thenoyltrifluoroacetonate and L1 = N,N'-bis(2-(8-hydroxyquinolinate)methylidene)-1,2-(R,R or S,S)-cyclohexanediamine), both in methanol solution and embedded in water dispersible and biocompatible poly lactic-co-glycolic acid (PLGA) nanoparticles. Thanks to their absorption properties in a wide range of wavelengths extending from the UV up to the blue and green visible regions, the emission of these complexes can be effectively sensitized using visible radiation, which is much less harmful to tissues and skin than the UV one. The encapsulation of the two Ln(III)-based complexes in PLGA allows us to preserve their nature, making them stable in water and to test their cytotoxicity on two different cell lines, with the aim of using them in the future as potential bioimaging optical probes.

7.
Chemistry ; 28(37): e202200574, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35481882

RESUMO

We report the first example of very efficient NIR Circularly Polarized Luminescence (CPL) (around 970 nm) in water, obtained thanks to the combined use of a chiral Yb complex and of poly lactic-co-glycolic acid (PLGA) nanoparticles. [YbL(tta)2 ]CH3 COO (L=N, N'-bis(2-pyridylmethylidene)-1,2-(R,R+S,S) cyclohexanediamine and tta=2-thenoyltrifluoroacetonate) shows good CPL in organic solvents, because the tta ligands efficiently sensitize Yb NIR luminescence and the readily prepared chiral ligand L endows the complex with the necessary dissymmetry. PLGA nanoparticles incorporate the complex and protect the metal ion from the intrusion of solvent molecules, while ensuring biocompatibility, water solubility and stability to the complex. Hydrophilic NIR-CPL optical probes can find applications in the field of NIR-CPL bio-assays.


Assuntos
Luminescência , Nanopartículas , Ligantes , Medições Luminescentes , Água
8.
Chemistry ; 28(33): e202200200, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35394095

RESUMO

The chiral cationic complex [Ru(η1 -OAc)(CO)((R,R)-Skewphos)(phen)]OAc (2R ), isolated from reaction of [Ru(η1 -OAc)(η2 -OAc)(R,R)-Skewphos)(CO)] (1R ) with phen, reacts with NaOPiv and KSAc affording [RuX(CO)((R,R)-Skewphos)(phen)]Y (X=Y=OPiv 3R ; X=SAc, Y=OAc 4R ). The corresponding enantiomers 2S -4S have been obtained from 1S containing (S,S)-Skewphos. Reaction of 2R and 2S with (S)-cysteine and NaPF6 at pH=9 gives the diastereoisomers [Ru((S)-Cys)(CO)(PP)(phen)]PF6 (PP=(R,R)-Skewphos 2R -Cys; (S,S)-Skewphos 2S -Cys). The DFT energetic profile for 2R with (S)-cysteine in H2 O indicates that aquo and hydroxo species are involved in formation of 2R -Cys. The stability of the ruthenium complexes in 0.9 % w/v NaCl solution, PBS and complete DMEM medium, as well as their n-octanol/water partition coefficient (logP), have been evaluated. The chiral complexes show high cytotoxic activity against SW1736, 8505 C, HCT-116 and A549 cell lines with EC50 values of 2.8-0.04 µM. The (R,R)-Skewphos derivatives show higher cytotoxicity compared to their enantiomers, 4R (EC50 =0.04 µM) being 14 times more cytotoxic than 4S against the anaplastic thyroid cancer 8505 C cell line.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Rutênio , Antineoplásicos/farmacologia , Cátions , Linhagem Celular Tumoral , Complexos de Coordenação/toxicidade , Cisteína , Estereoisomerismo
9.
Inorg Chem ; 61(41): 16333-16346, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36201622

RESUMO

In this work, we investigated from a theoretical point of view the dynamics of the energy transfer process from the ligand to Eu(III) ion for 12 isomeric species originating from six different complexes differing by nature of the ligand and the total charge. The cationic complexes present the general formula [Eu(L)(H2O)2]+ (where L = bpcd2- = N,N'-bis(2-pyridylmethyl)-trans-1,2-diaminocyclohexane N,N'-diacetate; bQcd2- = N,N'-bis(2-quinolinmethyl)-trans-1,2-diaminocyclohexane N,N'-diacetate; and bisoQcd2- = N,N'-bis(2-isoquinolinmethyl)-trans-1,2-diaminocyclohexane N,N'-diacetate), while the neutral complexes present the Eu(L)(H2O)2 formula (where L = PyC3A3- = N-picolyl-N,N',N'-trans-1,2-cyclohexylenediaminetriacetate; QC3A3- = N-quinolyl-N,N',N'-trans-1,2-cyclohexylenediaminetriacetate; and isoQC3A3- = N-isoquinolyl-N,N',N'-trans-1,2-cyclohexylenediaminetriacetate). Time-dependent density functional theory (TD-DFT) calculations provided the energy of the ligand excited donor states, distances between donor and acceptor orbitals involved in the energy transfer mechanism (RL), spin-orbit coupling matrix elements, and excited-state reorganization energies. The intramolecular energy transfer (IET) rates for both singlet-triplet intersystem crossing and ligand-to-metal (and vice versa) involving a multitude of ligand and Eu(III) levels and the theoretical overall quantum yields (ϕovl) were calculated (the latter for the first time without the introduction of experimental parameters). This was achieved using a blend of DFT, Judd-Ofelt theory, IET theory, and rate equation modeling. Thanks to this study, for each isomeric species, the most efficient IET process feeding the Eu(III) excited state, its related physical mechanism (exchange interaction), and the reasons for a better or worse overall energy transfer efficiency (ηsens) in the different complexes were determined. The spectroscopically measured ϕovl values are in good agreement with the ones obtained theoretically in this work.

10.
Epidemiol Prev ; 46(1-2): 84-91, 2022.
Artigo em Italiano | MEDLINE | ID: mdl-35354271

RESUMO

OBJECTIVES: to evaluate and validate the adoption of an algorithm for the identification of cases of congenital anomalies (CAs) to improve the performance of the Congenital Malformations Registry of Sicily Region (Southern Italy). DESIGN: an algorithm was used to identify congenital anomalies on a sample of hospital discharge records (SDO) with ICD-9-CM code between 740-759 on any of the diagnoses within the first year of life, together with a sample of healthy births equal to 5% of total births for the same period. The identified cases were evaluated through the clinical record analysis. SETTING AND PARTICIPANTS: the analysed sample was composed of 4,271 cases identified between June 2013 and December 2014 along with 3,993 SDO without any code of MC (5% of the total volume of births in the same period). MAIN OUTCOME MEASURES: positive predictive value (VPP) and negative predictive value (VPN) were computed by means of the comparison between the algorithm outcomes and the clinical record verification. RESULTS: 4,271 potentially malformed records involving 3,381 subjects born in the Sicilian territory have been identified. Among the hospital discharge records that it was possible to verify, the application of the algorithm led to the exclusion of 924 cases: of these, 62 proved to be false negatives (VPN: 93.3). The valid cases were 1,179, while the cases to be evaluated 617: the comparison between algorithm and clinical record analysis led to a VPP of 91.7 and 72.1, respectively, for valid and to be evaluated. CONCLUSIONS: the tested algorithm proved to be a useful tool for identifying SDO potentially related to congenital anomalies. In the overall sample, the algorithm provided an outcome consistent with the clinical record assessment in 87.4% (2,379) of cases.


Assuntos
Registros Hospitalares , Alta do Paciente , Algoritmos , Hospitais , Humanos , Sicília/epidemiologia
11.
J Chem Phys ; 155(10): 104301, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34525822

RESUMO

In this paper, we present a comparative study of the redox properties of the icosahedral [Rh12E(CO)27]n- (n = 4 when E = Ge or Sn and n = 3 when E = Sb or Bi) family of clusters through in situ infrared spectroelectrochemistry experiments and density functional theory computational studies. These clusters show shared characteristics in terms of molecular structure, being all E-centered icosahedral species, and electron counting, possessing 170 valence electrons as predicted by the electron-counting rules, based on the cluster-borane analogy, for compounds with such metal geometry. However, in some cases, clusters of similar nuclearity, and beyond, may show multivalence behavior and may be stable with a different electron counting, at least on the time scale of the electrochemical analyses. The experimental results, confirmed by theoretical calculations, showed a remarkable electron-sponge behavior for [Rh12Ge(CO)27]4- (1), [Rh12Sb(CO)27]3- (3), and [Rh12Bi(CO)27]3- (4), with a cluster charge going from -2 to -6 for 1 and 3 and from -2 to -7 for cluster 4, making them examples of molecular electron reservoirs. The [Rh12Sn(CO)27]4- (2) derivative, conversely, presents a limited ability to exist in separable reduced cluster species, at least within the experimental conditions, while in the gas phase it appears to be stable both as a penta- and hexa-anion, therefore showing a similar redox activity as its congeners. As a fallout of those studies, during the preparation of [Rh12Sb(CO)27]3-, we were able to isolate a new species, namely, [Rh11Sb(CO)26]2-, which presents a Sb-centered nido-icosahedral metal structure possessing 158 cluster valence electrons, in perfect agreement with the polyhedral skeletal electron pair theory.

12.
Inorg Chem ; 59(7): 4300-4310, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32207932

RESUMO

The reactivity of [Rh7(CO)16]3- with SbCl3 has been deeply investigated with the aim of finding a new approach to prepare atomically precise metalloid clusters. In particular, by varying the stoichiometric ratios, the reaction atmosphere (carbon monoxide or nitrogen), the solvent, and by working at room temperature and low pressure, we were able to prepare two large carbonyl clusters of nanometer size, namely, [Rh20Sb3(CO)36]3- and [Rh21Sb2(CO)38]5-. A third large species composed of 28 metal atoms was isolated, but its exact formulation in terms of metal stoichiometry could not be incontrovertibly confirmed. We also adopted an alternative approach to synthesize nanoclusters, by decomposing the already known [Rh12Sb(CO)27]3- species with PPh3, willing to generate unsaturated fragments that could condense to larger species. This strategy resulted in the formation of the lower-nuclearity [Rh10Sb(CO)21PPh3]3- heteroleptic cluster instead. All three new compounds were characterized by IR spectroscopy, and their molecular structures were fully established by single-crystal X-ray diffraction studies. These showed a distinct propensity for such clusters to adopt an icosahedral-based geometry. Their characterization was completed by ESI-MS and NMR studies. The electronic properties of the high-yield [Rh21Sb2(CO)38]5- cluster were studied through cyclic voltammetry and in situ infrared spectroelectrochemistry, and the obtained results indicate a multivalent nature.

13.
Inorg Chem ; 59(21): 16016-16026, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33086004

RESUMO

The reaction of [Ni6(CO)12]2- as a [NBu4]+ salt in CH2Cl2 with 0.8 equiv of PCl3 afforded [Ni14P2(CO)22]2-. In contrast, the reactions of [Ni6(CO)12]2- as a [NEt4]+ salt with 0.4-0.5 equiv of POCl3 afforded [Ni22-xP2(CO)29-x]4- (x = 0.84) or [Ni39P3(CO)44]6- by using CH3CN and thf as a solvent, respectively. Moreover, by using 0.7-0.9 mol of POCl3 per mole of [NEt4]2[Ni6(CO)12] both in CH3CN and thf, [Ni23-xP2(CO)30-x]4- (x = 0.82) was obtained together with [Ni22P6(CO)30]2- as a side product. [Ni23-xP2(CO)30-x]4- (x = 0.82) and [Ni22P6(CO)30]2- were separated owing to their different solubility in organic solvents. All the new molecular nickel phosphide carbonyl nanoclusters were structurally characterized through single crystal X-ray diffraction (SC-XRD) as [NBu4]2[Ni14P2(CO)22] (two different polymorphs, P21/n and C2/c), [NEt4]4[Ni23-xP2(CO)30-x]·CH3COCH3·solv (x = 0.82), [NEt4]2[Ni22P6(CO)30]·2thf, [NEt4]4[Ni22-xP2(CO)29-x]·2CH3COCH3( x = 0.84) and [NEt4]6[Ni39P3(CO)44]·C6H14·solv. The metal cores' sizes of these clusters range from 0.59 to 1.10 nm, and their overall dimensions including the CO ligands are 1.16-1.63 nm. In this respect, they are comparable to ultrasmall metal nanoparticles, molecular nanoclusters, or atomically precise metal nanoparticles. The environment of the P atoms within these molecular Ni-P-CO nanoclusters displays a rich diversity, that is, Ni5P pentagonal pyramid, Ni7P monocapped trigonal prism, Ni8P bicapped trigonal prism, Ni9P monocapped square antiprism, Ni10P sphenocorona, Ni10P bicapped square antiprism, and Ni12P icosahedron.

14.
Org Biomol Chem ; 18(43): 8793-8809, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33084717

RESUMO

Sulfur ylides first disclosed in 1930 started to gain more attention in the 1960s, thanks mainly to the studies by Corey and Chaykovsky on their use for the preparation of strained rings. More recently, the chemistry of these compounds has experienced important growth, in part due to the similarity of their reactivities with diazo compounds. This short review provides an overview on the great assortment of reactions of sulfoxonium ylides, outlining a comparison between the chemistry of these ylides and their congeners: sulfonium ylides and diazo compounds. Insertion reactions, cyclisation reactions and ring-opening reactions are highlighted, giving particular attention to catalytic asymmetric methodologies.

15.
Acc Chem Res ; 51(11): 2748-2755, 2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30346730

RESUMO

Chemical research in synthesizing metal nanoparticles has been a major topic in the last two decades, as nanoparticles can be of great interest in many fields such as biology, catalysis, and nanotechnology. However, as their chemical and physical properties are size-dependent, the reliable preparation of nanoparticles at a molecular level is highly desirable. Despite the remarkable advances in recent years in the preparation of thiolate- or p-MBA or PA-protected gold and silver nanoclusters ( p-MBA = p-mercaptobenzoic acid; PA = phenylalkynyl), as well as the large palladium clusters protected by carbonyl and phosphine ligands that initially dominated the field, the synthesis of monodispersed and atomically precise nanoparticles still represents a great challenge for chemists. Carbonyl cluster compounds of high nuclearity have become more and more part of a niche chemistry, probably owing to their handling issues and expensive synthesis. However, even in large size, they are known at a molecular level and therefore can play a relevant role in understanding the structures of nanoparticles in general. For instance the icosahedral pattern, proper of large gold nanoparticles, is also found in some Au-Fe carbonyl cluster compounds. Rh clusters in general can also be employed as precursors in homo- and heterogeneous catalysis, and the possibility of doping them with other elements at the molecular level is an important additional feature. The fact that they can be obtained as large crystalline species, with dimensions of about 2 nm, allows one to place them not only in the nanometric regime, but also in the ultrafine-metal-nanoparticle category, which lately has been attracting growing attention. In fact, such small nanoparticles possess an even higher density of active catalytic sites than their larger (up to 100 nm) equivalents, hence enhancing atom efficiency and reducing the cost of precious-metal catalysts. Finally, the clusters' well-defined morphology could, in principle, contribute to expand the studies on the shape effects of nanocatalysts. In this Account, we want to provide the scientific community with some insights on the preparation of rhodium-containing carbonyl compounds of increasing nuclearity. Among them, we present the synthesis and molecular structures of two new heterometallic nanoclusters, namely, [Rh23Ge3(CO)41]5- and [Rh16Au6(CO)36]6-, which have been obtained by reacting a rhodium-cluster precursor with Ge(II) and Au(III) salts. The growth of such clusters is induced by redox mechanisms, which allow going from mononuclear complexes up to clusters with over 20 metal atoms, thus entering the nanosized regime.

16.
Indoor Air ; 29(2): 276-290, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30580463

RESUMO

This study aimed at surveying lower secondary schools in southern Italy, in a highly polluted area. A community close to an industrial area and three villages in rural areas was investigated. Indoor temperature, relative humidity (RH), gaseous pollutants (CO2 and NO2 ), selected biological pollutants in indoor dust, and the indoor/outdoor mass concentration and elemental composition of PM2.5 were ascertained. Temperature and RH were within, or close to, the comfort range, while CO2 frequently exceeded the threshold of 1000 ppm, indicating inadequate air exchange rate. In all the classrooms, median NO2 levels were above the WHO threshold value. Dermatophagoides p. allergen concentration was below the sensitizing threshold, while high endotoxin levels were detected in the classrooms, suggesting schools may produce significant risks of endotoxin exposure. Concentration and solubility of PM2.5 elements were used to identify the sources of indoor particles. Indoor concentration of most elements was higher than outdoors. Resuspension was responsible for the indoor increase in soil components. For elements from industrial emission (Cd, Co, Ni, Pb, Sb, Tl, V), the indoor concentration depended on penetration from the outside. For these elements, differences in rural vs industrial concentrations were found, suggesting industrial sources may influence indoor air quality nearby schools.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Monóxido de Carbono/análise , Poeira/análise , Metais Pesados/análise , Dióxido de Nitrogênio/análise , Material Particulado/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Humanos , Umidade , Região do Mediterrâneo , Tamanho da Partícula , População Rural , Instituições Acadêmicas , Sicília , Temperatura , Ventilação
17.
Environ Res ; 165: 71-80, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29674239

RESUMO

Cigarette smoke is the main source of indoor chemical and toxic elements. Cadmium (Cd), Thallium (Tl), Lead (Pb) and Antimony (Sb) are important contributors to smoke-related health risks. Data on the association between Rare Earth Elements (REE) Cerium (Ce) and Lanthanum (La) and domestic smoking are scanty. To evaluate the relationship between cigarette smoke, indoor levels of PM2.5 and heavy metals, 73 children were investigated by parental questionnaire and skin prick tests. The houses of residence of 41 "cases" and 32 "controls" (children with and without respiratory symptoms, respectively) were evaluated by 48-h PM2.5 indoor/outdoor monitoring. PM2.5 mass concentration was determined by gravimetry; the extracted and mineralized fractions of elements (As, Cd, Ce, La, Mn, Pb, Sb, Sr, Tl) were evaluated by ICP-MS. PM2.5 and Ce, La, Cd, and Tl indoor concentrations were higher in smoker dwellings. When corrected for confounding factors, PM2.5, Ce, La, Cd, and Tl were associated with more likely presence of respiratory symptoms in adolescents. We found that: i) indoor smoking is associated with increased levels of PM2.5, Ce, La, Cd, and Tl and ii) the latter with increased presence of respiratory symptoms in children.


Assuntos
Poluentes Atmosféricos , Habitação , Metais Terras Raras , Material Particulado , Fumar , Adolescente , Poluentes Atmosféricos/química , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Criança , Habitação/estatística & dados numéricos , Humanos , Itália , Metais/química , Metais Terras Raras/química , Material Particulado/química
18.
Pediatr Allergy Immunol ; 28(7): 675-682, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28783215

RESUMO

BACKGROUND: Indoor allergens are risk factors for asthma: Thus, the characterization of indoor air quality is important for studying environment-health relationships in children. In particular, Dermatophagoides pteronyssinus is the dominant allergen for asthma. We cross-sectionally investigated the relationships among respiratory symptoms and function, airway inflammation, allergen sensitization, and indoor allergen concentration. METHODS: One hundred and thirty-two children aging 10-14 years and living in a Southern Mediterranean area were evaluated by parental questionnaires. Spirometry, exhaled nitric oxide (FeNO), skin prick tests, total, and specific serum IgE analyses were performed along with the evaluation of home dust samples for the content in Der p 1 allergen. Three clusters were created on the basis of the presence/absence of wheeze in the last 12 months (Wh12m) and Der p 1-specific IgE level. RESULTS: Cluster 1 (Wh12m+/high Der p 1 IgE) presented higher FeNO and poorer pulmonary function (lower FEV1 and FEF25%-75% ), while its symptom score was not different from Cluster 2 (Wh12m+/low Der p 1 IgE). Cluster 3 (Wh12m-/low IgE) showed the lowest FeNO values and pulmonary function similar to Cluster 2. Within Cluster 1, both Der p 1-specific IgE and FeNO were positively correlated with dust Der p 1. CONCLUSIONS: Similar asthma phenotypes may occur in children despite differences in their atopic state. In atopic children, sensitizing allergens in the indoor environment may increase airway inflammation worsening pulmonary function. Moreover, environmental exposures may contribute to the development of asthma-like symptoms also in the absence of atopic sensitization, thus contributing to asthma overdiagnosis.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Alérgenos/imunologia , Asma/diagnóstico , Pyroglyphidae/imunologia , Adolescente , Poluição do Ar em Ambientes Fechados/efeitos adversos , Animais , Criança , Análise por Conglomerados , Estudos Transversais , Exposição Ambiental , Feminino , Humanos , Imunoglobulina E/sangue , Masculino , Região do Mediterrâneo/epidemiologia , Óxido Nítrico/análise , Fenótipo , Fatores de Risco , Testes Cutâneos , Espirometria , Inquéritos e Questionários
19.
Inorg Chem ; 56(11): 6343-6351, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28520423

RESUMO

The reaction of [Rh7(CO)16]3- with BiCl3 under N2 and at room temperature results in the formation of the new heterometallic [Bi@Rh12(CO)27]3- cluster in high yields. Further controlled addition of BiCl3 leads first to the formation of the dimeric [(Bi@Rh12(CO)26)2Bi]5- and the closo-[Bi@Rh14(CO)27Bi2]3- species in low yields, and finally, to the [Bi@Rh17(CO)33Bi2]4- cluster. All clusters were spectroscopically characterized by IR and electrospray ionization mass spectrometry, and their molecular structures were fully determined by X-ray diffraction studies. Notably, they represent the first examples of Bi atoms interstitially lodged in metallic cages that, in this specific case, are all based on an icosahedral geometry. Moreover, [Bi@Rh14(CO)27Bi2]3- forms an exceptional network of infinite zigzag chains in the solid state, thanks to intermolecular Bi-Bi distances.

20.
Environ Res ; 138: 8-16, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25682253

RESUMO

BACKGROUND: High levels of indoor NO2 are associated with increased asthma symptoms and decreased expiratory peak flows in children. We investigated the association of exposure to domestic indoor NO2, objectively measured in winter and spring, with respiratory symptoms and lung function in a sample of adolescents from a southern Mediterranean area. METHODS: From a large school population sample (n=2150) participating in an epidemiological survey in the urban area of the City of Palermo (southern Italy), a sub-sample of 303 adolescents was selected which furnished an enriched sample for cases of current asthma. All subjects were evaluated by a health questionnaire, skin prick tests and spirometry. One-week indoor NO2 monitoring of their homes was performed by diffusive sampling during spring and again during winter. RESULTS: We found that about 25% of subjects were exposed to indoor NO2 levels higher than the 40µg/m(3) World Health Organization limit, during both spring and winter. Moreover, subjects exposed to the highest indoor NO2 concentrations had increased frequency of current asthma (p=0.005), wheeze episodes in the last 12 months (p<0.001), chronic phlegm (p=0.013), and rhinoconjunctivitis (p=0.008). Finally, subjects with a personal history of wheeze ever had poorer respiratory function (FEF25-75%, p=0.01) when exposed to higher indoor NO2 concentrations. CONCLUSIONS: Home exposure to high indoor NO2 levels frequently occurs in adolescents living in a southern Mediterranean urban area and is significantly associated with the risks for increased frequency of both respiratory symptoms and reduced lung function.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar em Ambientes Fechados , Exposição Ambiental , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Dióxido de Nitrogênio/toxicidade , Doenças Respiratórias/fisiopatologia , Adolescente , Criança , Cidades , Estudos Transversais , Meio Ambiente , Monitoramento Ambiental , Feminino , Humanos , Itália , Masculino , Testes de Função Respiratória , Doenças Respiratórias/induzido quimicamente , Estações do Ano , Fatores Socioeconômicos
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