Perception and practice of sublingual immunotherapy among practicing allergists.

BACKGROUND: Currently, little information is available regarding who is using sublingual immunotherapy (SLIT) in the United States, what product they may be using, how they are dosing that product, and what perceived effect it may be having on patients. OBJECTIVE: To gather information regarding the perception and use of SLIT among practicing allergists in the United States. METHODS: On behalf of the American College of Allergy, Asthma and Immunology (ACAAI) Immunotherapy and Diagnostics Committee, an electronic survey was sent to all practicing allergists of the ACAAI in March 2007. RESULTS: The survey response rate was 25.7% (828/3,217) in which 92.5% of the respondents (766/828) practiced in the United States. For 61.7% (471/763) the most cited reason for not using SLIT was lack of approval by the Food and Drug Administration (FDA). If SLIT were an FDA-approved form of immunotherapy, 65.7% would use it to treat allergic rhinitis, 45.5% would use SLIT to treat patients younger than 5 years, and 40.9% would use it to treat moderate to severe asthma. A total of 5.9% (45/766) of US allergists reported using SLIT. Most perceived SLIT to be as effective (44.7%) or more effective (10.5%) than subcutaneous immunotherapy (SCIT). Most allergists who used SLIT (65.9%) had it reimbursed by patients paying out of pocket. The most commonly used extract (79.1%) was a commercially available extract used for SCIT. Some practitioners (53.5%) required their patients to administer doses of SLIT in their office, but 81.8% only required that this be done with the first dose. Practitioners gave epinephrine injectors to 41.5% of their patients receiving SLIT. CONCLUSIONS: Although only 5.9% of US allergists reported using SLIT, most of the 828 surveyed (766 US allergists) viewed SLIT as safe and effective and would consider using SLIT if it were an FDA-approved therapy.

CO adsorption on pure and binary-alloy gold clusters: a quantum chemical study.

We performed density-functional theory analysis of nondissociative CO adsorption on 22 binary Au-alloy (Au(n)M(m)) clusters: n=0-3, m=0-3, and m+n=2 (dimers) or 3 (trimers), M=Cu/Ag/Pd/Pt. We report basis-set superposition error corrections to adsorption energies and include both internal energy of adsorption (DeltaU(ads)) and Gibbs free energy of adsorption (DeltaG(ads)) at standard conditions (298.15 K and 1 atm). We found onefold (atop) CO binding on all the clusters except Pd2 (twofold/bridged), Pt2 (twofold/bridged), and Pd3 (threefold). In agreement with the experimental results, we found that CO adsorption is thermodynamically favorable on pure Au/Cu clusters but not on pure Ag clusters and also observed the following adsorption affinity trend: Pd>Pt>Au>Cu>Ag. For alloy dimers we found the following patterns: Au2>M Au>M2 (M=Ag/Cu) and M2>M Au>Au2 (M=Pd/Pt). Alloying Ag/Cu dimers with (more reactive) Au enhanced adsorption and the opposite effect was observed for PdPt dimers. The Ag-Au, Cu-Au, and Pd-Au trimers followed the trends observed on dimers: Au3>M Au2>M2Au>M3 (M=Ag/Cu) and Pd3>Pd2Au>PdAu2>Au3. Interestingly, Pt-Au trimers reacted differently and alloying with Au systematically increased the adsorption affinity: PtAu2>Pt2Au>Pt3>Au3. A strikingly different behavior of Pt is also manifested by the triplet spin state and onefold (atop) binding in Pt3-CO which is in contradiction with the singlet spin state and threefold binding in Pd3-CO. We found a linear correlation between CO binding energy (BE) and elongation of the CO bond. For Ag-Au and Cu-Au clusters, the increase in CO BE (and elongation of the C-O bond which is probably due to the back donation) is accompanied by the decrease in the cluster-CO distance suggesting that the donation (from 5sigma highest occupied molecular orbital in CO to cluster lowest unoccupied molecular orbital) mechanism also contributes to the BE. For Pd-Au clusters, the cluster-CO distance (and CO bond length) increases with increase in the BE, suggesting that the donation mechanism may not be important for those clusters. No clear trend was observed for Pt-Au clusters.