Heterogeneity of sensitization profiles and clinical phenotypes among patients with seasonal allergic rhinitis in Southern European countries-The @IT.2020 multicenter study

BACKGROUND

Pollen allergy poses a significant health and economic burden in Europe. Disease patterns are relatively homogeneous within Central and Northern European countries. However, no study broadly assessed the features of seasonal allergic rhinitis (SAR) across different Southern European countries with a standardized approach.

OBJECTIVE

To describe sensitization profiles and clinical phenotypes of pollen allergic patients in nine Southern European cities with a uniform methodological approach.

METHODS

Within the @IT.2020 multicenter observational study, pediatric and adult patients suffering from SAR were recruited in nine urban study centers located in seven countries. Clinical questionnaires, skin prick tests (SPT) and specific IgE (sIgE) tests with a customized multiplex assay (Euroimmun Labordiagnostika, Lübeck, Germany) were performed.

RESULTS

Three hundred forty-eight children (mean age 13.1 years, SD: 2.4 years) and 467 adults (mean age 35.7 years SD: 10.0 years) with a predominantly moderate to severe, persistent phenotype of SAR were recruited. Grass pollen major allergenic molecules (Phl p 1 and/or Phl p 5) ranged among the top three sensitizers in all study centers. Sensitization profiles were very heterogeneous, considering that patients in Rome were highly poly-sensitized (sIgE to 3.8 major allergenic molecules per patient), while mono-sensitization was prominent and heterogeneous in other cities, such as Marseille (sIgE to Cup a 1: n = 55/80, 68.8%) and Messina (sIgE to Par j 2: n = 47/82, 57.3%). Co-sensitization to perennial allergens, as well as allergic comorbidities also broadly varied between study centers.

CONCLUSIONS

In Southern European countries, pollen allergy is heterogeneous in terms of sensitization profiles and clinical manifestations. Despite the complexity, a unique molecular, multiplex, and customized in-vitro IgE test detected relevant sensitization in all study centers. Nevertheless, this geographical diversity in pollen allergic patients imposes localized clinical guidelines and study protocols for clinical trials of SAR in this climatically complex region.

Synthesis and characterization of metastable β-Ag2WO4: an experimental and theoretical approach

The geometry, cluster coordination and electronic structure of metastable β-Ag₂WO₄ microcrystals were elucidated using experimental techniques and first-principles calculations.

Differences in exhaled breath condensate pH measurements between samples obtained with two commercial devices

BACKGROUND

The objective of this study was to determine differences in EBC pH between samples obtained by RTube and EcoScreen, and to identify the effect of storage at -80 degrees C on the pH values.

METHODS

Twenty-three nonsmoking subjects with asthma or allergic rhinitis or without respiratory disease performed two sequential exhaled breath condensate (EBC) collections, using the RTube collection system and the EcoScreen condenser. EBC pH was measured immediately after collection and after storage at -80 degrees C for 8 weeks, without deaeration and repeated following deaeration with Argon.

RESULTS

In EBC samples without deaeration, the EcoScreen pH values were significantly higher than the RTube pH values (mean difference, 0.32; 95% CI, 0.21-0.44, P < 0.0001). In deaerated EBC samples, the EcoScreen pH values were also significantly higher than the RTube pH values (mean difference, 0.12; 95% CI, 0.01-0.25, P=0.04). For both EBC collection systems, storage for 8 weeks had a significant influence on pH of nondeaerated samples.

CONCLUSIONS

The present study demonstrates that EBC pH value is dependent on the collection device used and that the storage for 8 weeks had a significant influence on the pH of samples analyzed without deaeration.

Preparation and Properties of the Full Series of Cuboidal Clusters [MoxW4-xSe4(H2O)12]n+ (n = 4−6) and Their Derivatives

Hydrothermal reactions between incomplete cuboidal cluster aqua complexes [M3Q4(H2O)9]4+ and M(CO)6 (M = Mo, W; Q = S, Se) offer easy access to the corresponding cuboidal clusters M4Q4. The complete series of homometal and mixed Mo/W clusters [Mo(x)W4-xQ4(H2O)12]n+ (x = 0-4, n = 4-6) has been prepared. Upon oxidation of the mixed-metal clusters, it is the W atom which is lost, allowing selective preparation of new trinuclear clusters [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+. The aqua complexes were converted by ligand exchange reactions into dithiophosphato and thiocyanato complexes, and crystal structures of [W4S4((EtO)2PS2)6], [MoW3S4((EtO)2PS2)6], [Mo4Se4((EtO)2PS2)6], [W4Se4((i-PrO)2PS2)6], and (NH4)6[W4Se4(NCS)12]-4H20 were determined. Cyclic voltammetry was performed on [Mo(x)W4-xCO4(H2O)12]n+, showing reversible redox waves 6+/5+ and 5+/4+. The lower oxidation states are more difficult to access as the number of W atoms increases. The [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+ species were derivatized into [Mo2WSe4(acac)3(py)3]+ and [MoW2Se4(acac)3(py)3]+, which were also studied by CV. When appropriate, the products were also characterized by FAB-MS and NMR (31P, 1H) data.

Synthesis, structure, and optical-limiting properties of heterobimetallic [M(3)CuS(4)] cuboidal clusters (M = Mo or W) with terminal phosphine ligands

Cubane-type clusters of formula [Mo(3)CuS(4)Cl(4)(dmpe)(3)](PF(6)) (4), [Mo(3)CuS(4)Br(4)(dmpe)(3)](PF(6)) (5), and [W(3)CuS(4)Br(4)(dmpe)(3)](PF(6)) (6) have been prepared by reacting the incomplete cuboidal trimers [Mo(3)S(4)Cl(3)(dmpe)(3)](PF(6)) (1), [Mo(3)S(4)Br(3)(dmpe)(3)](PF(6)) (2), and [W(3)S(4)Br(3)(dmpe)(3)](PF(6)) (3), respectively, with CuX (X = Cl or Br) or the mononuclear copper complex [Cu(CH(3)CN)(4)](+) in THF. The reaction takes place without global changes in the metal oxidation states, and compounds 4-6 with a [M(3)CuS(4)](5+) core possess 16 e(-) for metal-metal bonding. X-ray structural analysis of 4-6 revealed an effective C(3v) symmetry for the M(3)Cu unit with the M-M distances being statistically the same for M = Mo or W. However, the M-Cu distance is 0.04 and 0.1 A longer than the M-M bond length for Mo and W, respectively. There is no significant structural rearrangement of the ligand-metal bonding in proceeding from [M(3)S(4)X(3)(dmpe)(3)](+) to [M(3)CuS(4)X(4)(dmpe)(3)](+). The cyclic voltammograms of the [Mo(3)CuS(4)] cubane clusters show one quasi-reversible reduction process at E(1/2) = -0.31 V for 4 and at E(1/2) = -0.23 V for 5 and one irreversible reduction at -0.69 and -0.58 V for 4 and 5, respectively. The tungsten cluster 6 shows a unique quasi-reversible reduction wave at E(1/2) = -0.71 V. The incorporation of copper into the incomplete [M(3)S(4)] cuboidal complexes produces a decrease of the reduction potential for both molybdenum and tungsten. Absorption spectra of 1-6 are broadly similar; replacing Mo by W in proceeding from 2 to 3 or from 5 to 6 and replacing Br by Cl in proceeding from 2 to 1 or from 5 to 4 results in a blue shift of the three UV-visible absorption bands. All six clusters exhibit optical limiting, as measured by the Z-scan technique at 523 nm using 40 ns pulses. The power-limiting mechanism remains obscure, but under the conditions employed, threshold-limiting fluence decreases on replacing W by Mo on proceeding from 3 to 2 or 6 to 5 and on proceeding from tetranuclear cluster (4-6) to trinuclear precursor (1-3, respectively). For all six clusters, values of the excited-state cross section sigma(eff) are larger than those of the corresponding ground-state cross section sigma(0); i.e., all clusters are efficient optical limiters.

[Fe(Phen)(CN)4]-: a versatile building block for the design of heterometallic systems. Crystal structures and magnetic properties of PPh4[Fe(Phen)(CN)4]*2H2O and [[Fe(Phen)(CN)4]2M(H2O)2]*4H2O [Phen = 1,10-phenanthroline; M = Mn(II) and Zn(II)]

The mononuclear PPh4[Fe(phen)(CN)4]*2H2O (1) complex and the cyanide-bridged bimetallic [[Fe(phen)(CN)4]2M(H2O)2]*4H2O compounds [M = Mn(II) (2) and Zn(II) (3); phen = 1,10-phenanthroline; PPh4 = tetraphenylphosphonium cation] have been synthesized and structurally and magnetically characterized. Complex 1 crystallizes in the monoclinic system, space group P2(1)/c, with a = 9.364(4) A, b = 27.472(5) A, c = 14.301(3) A, beta = 97.68(2) degrees, and Z = 4. Complexes 2 and 3 are isostructural and they crystallize in the monoclinic system, space group P2(1)/n, with a = 7.5292(4) A, b = 15.6000(10) A, c = 15.4081(9) A, beta = 93.552(2) degrees, and Z = 2 for 2 and a = 7.440(1) A, b = 15.569(3) A, c = 15.344(6) A, beta = 93.63(2) degrees, and Z = 2 for 3. The structure of complex 1 is made up of mononuclear [Fe(phen)(CN)4]- anions, tetraphenyphosphonium cations, and water molecules of crystallization. The iron(III) is hexacoordinate with two nitrogen atoms of a chelating phen (2.018(6) and 2.021(6) A for Fe-N) and four carbon atoms of four terminal cyanide groups (Fe-C bond lengths varying in the range 1.906(8)-1.95(1) A) building a distorted octahedron around the metal atom. The structure of complexes 2 and 3 consists of neutral double zigzag chains of formula [[Fe(phen)(CN)4]2M(H2O)2] and crystallization water molecules. The [Fe(phen)(CN)4]- entity of 1 is present in 2 and 3 acting as a bridging ligand toward M(H2O)2 units [M = Mn(II) (2) and Zn(II) (3)] through two cyanide groups in cis positions, the other two cyanide remaining terminal. Two water molecules in trans positions and four cyanide-nitrogen atoms from four [Fe(phen)(CN)4]- units build a distorted octahedral surrounding Mn(II) (2) and Zn(II) (3). The M-O bond lengths are 2.185(3) (2) and 2.105(3) A (3), whereas the M-N bond distances vary in the ranges 2.210(3)-2.258(3) A (2) and 2.112(3)-2.186(3) A (3). The structure of the [Fe(phen)(CN)4]- complex ligand in 2 and 3 is as in 1. The shorter intrachain Fe-M distances through bridging cyano are 5.245(5) and 5.208(5) A in 2 and 5.187(1) and 5.132(1) A in 3. The magnetic properties of 1-3 have been investigated in the temperature range 2.0-300 K. Complex 1 is a low-spin iron(III) complex with an appreciable orbital contribution. The magnetic properties of 3 correspond to the sum of two magnetically isolated spin triplets, the magnetic coupling between the low-spin iron(III) centers through the -CN-Zn-NC- bridging skeleton (iron-iron separation larger than 10.2 A) being negligible. More interestingly, 2 exhibits one-dimensional ferrimagnetic behavior due to the noncompensation of the local interacting spins (S(Mn) = 5/2 and S(Fe) = 1/2) which interact antiferromagnetically through bridging cyano groups. A comparison between the magnetic properties of the isostructural compounds 2 and 3 allow us to check the antiferromagnetic coupling in 2.