Starting from phenols R1,R2ArOH (5) and the anisole derivative 3,5‐di‐tert‐butyl‐2‐methoxybenzyl bromide (13), a series of new tacn‐based ligands (R1,R2ArOR3)3tacn (2) have been synthesized with ...substituents of varying bulkiness and electronic nature at the ortho and para positions with respect to the oxygen coordination site. It was observed that these groups not only determine the steric shielding and solubility properties of 2, but also deactivate the reactivity of the phenols in the modified Mannich reaction when electron‐withdrawing groups are introduced at the para position in 5. Treatment of the ligands with UCl4 in thf led to the isolation of four uranium(IV) chloro complexes {(R1,R2ArO)3tacn}UIVCl (14), which were characterized by different spectroscopic and physical methods (e.g., 1H NMR, UV/Vis, SQUID), corroborating the +4 oxidation state in 14. Single‐crystal X‐ray structure analyses revealed that 14a·CH2Cl2·CH3CN and 14b·1.25CH2Cl2 crystallize in the chiral, orthorhombic space group P212121 a = 24.934(3), b = 27.941(3), c = 9.045(1) Å, V = 6302(2) Å3, Z = 4 and the chiral, hexagonal space group P63 a = 22.097(3), c = 17.941(2) Å, V = 7587(2) Å3, Z = 4, respectively. Interestingly, complexes 14a,b self‐organize in the solid state into homochiral 1D polymeric superstructures as a result of weak intermolecular C–H···Cl contacts.
A series of tacn‐based ligands (R1,R2ArOR3)3tacn have been synthesized with substituents of varying bulkiness and electronic nature. Treatment of the ligands with UCl4 afforded uranium(IV) chloro complexes {(R1,R2ArO)3tacn}UIVCl, which self‐organize in the solid state into homochiral 1D polymeric strands as a result of weak intermolecular C–H···Cl contacts.
To cite this article: Schulten V, Nagl B, Scala E, Bernardi ML, Mari A, Ciardiello MA, Lauer I, Scheurer S, Briza P, Jürets A, Ferreira F, Jahn‐Schmid B, Fischer GF, Bohle B. Pru p 3, the nonspecific ...lipid transfer protein from peach, dominates the immune response to its homolog in hazelnut. Allergy 2011; 66: 1005–1013.
Background: Nonspecific lipid transfer proteins (nsLTPs) are important food allergens. Often, patients allergic to the nsLTP in peach suffer from allergy to hazelnuts. We aimed to analyse the T‐cell response to Cor a 8, the nsLTP in hazelnut and its immunological cross‐reactivity with the nsLTP in peach, Pru p 3.
Methods: Cor a 8‐reactive T‐cell lines (TCL) established from patients allergic to hazelnut and peach were stimulated with 12‐mer peptides representing the complete amino acid sequence of Cor a 8 to identify its T‐cell‐activating regions and with Pru p 3 to investigate cellular cross‐reactivity. T‐cell clones specific for different major T‐cell‐activating regions of Pru p 3 were stimulated with Cor a 8. Both nsLTPs were subjected to endolysosomal degradation assays. Immunoglobulin E (IgE) cross‐reactivity between Cor a 8 and Pru p 3 was assessed in inhibition enzyme‐linked immunosorbent assay.
Results: No major T‐cell‐activating region was found among 26 T‐cell‐reactive peptides identified in Cor a 8. Although generated with Cor a 8, 62% of the TCL responded more strongly to Pru p 3. This cross‐reactivity was mediated by T cells specific for the immunodominant region Pru p 361–75. Peptide clusters encompassing this region were generated during lysosomal degradation of both nsLTPs. Cor a 8 was more rapidly degraded by lysosomal proteases than Pru p 3. Pre‐incubation of sera with Pru p 3 completely abolished IgE binding to Cor a 8, which was not the case vice versa.
Conclusions: T‐cell reactivity to Cor a 8 is predominantly based on cross‐reactivity with Pru p 3, indicating that the latter initiates sensitisation to its homolog in hazelnut. The limited allergenic potential of Cor a 8 seems to be associated with rapid lysosomal degradation during allergen processing and the lack of major T‐cell‐activating regions.
Applications of hybrid QM/MM methods range from reactions in active sites of small enzymes to multiple sites in large bioenergetic complexes. By combining the widely used molecular dynamics and ...visualization programs NAMD/VMD with the quantum chemistry packages ORCA, and MOPAC, we provide an integrated, comprehensive, customizable, and easy-to-use suite. Through the QwikMD interface, setup, execution, visualization, and analysis are streamlined for all levels of expertise.
High-spin states in 105Rh were populated by the 96Zr(13C, p3n) reaction at beam energies of 51 and 58 MeV, and studied using the EUROBALL IV γ-ray spectrometer and the DIAMANT charged particle array. ...A pair of nearly degenerate ΔI=1 three-quasiparticle bands with the same spins and parity have been observed. Comparison of the experimental results with tilted axis cranking calculations confirms the chiral character of the two bands, while arguments based on the excitation of particles within the πg9/2ν(h11/2)2 configuration of the yrast band and comparison with the previously observed γ band exclude the other possible interpretations. This is the first experimental evidence for three-quasiparticle chiral structure in the A not, vert, similar 100 region, and the first simultaneous observation of a γ band and chiral partner bands in one nucleus.
The prevalence of infective endocarditis (IE) among children with Staphylococcus aureus bacteremia (SAB) is unknown. The objective of this study was to determine prospectively the prevalence of IE ...among pediatric patients with SAB in a large tertiary care center.
Between July 1998 and June 2001, all children who developed SAB whose parent/guardian signed informed consent underwent echocardiography. Clinical and follow-up results were collected prospectively. Endocarditis was classified according to the modified Duke criteria.
Fifty-one children developed SAB during the study interval. Definite (6 patients 11.8%) or possible (4 patients 7.8%) IE was present in 10 of 51 (20%) children with SAB. Most children (73%) developed bacteremia as a consequence of an infected intravascular device. Children with underlying congenital heart disease had a significantly higher prevalence of definite or possible IE, compared with those with structurally normal hearts (53% vs 3%). All patients with definite IE had multiple positive blood cultures. Mortality was high among patients with and without IE (40% vs 12%).
In this study, the prevalence of definite IE among children with SAB was approximately 12% and was frequently associated with congenital heart disease and multiple positive blood cultures. The mortality for children with SAB and definite or possible S aureus IE is high.
Die Umsetzung des CoI‐Komplexes (TIMMNmes)CoI(PF6) (1) (TIMMNmes=tris‐2‐(3‐Mesityl‐imidazolin‐2‐yliden)‐methylamin) mit Mesitylazid ergibt das CoIII‐Imid (TIMMNmes)CoIII(NMes)(PF6) (2). Folgende ...Oxidation mit FeCp2(PF6) ermöglicht den Zugang zu dem seltenen CoIII‐Imidylkomplex (TIMMNmes)Co(NMes)(PF6)2 (3). Einkristall‐Röntgenstrukturanalyse und ESR‐Spektroskopie bestätigen die molekulare Struktur von 3 und seinen S=1/2
Grundzustand. ENDOR, Röntgenabsorptionsspektroskopie und quantenchemische Rechnungen belegen eine ligandenbasierte Oxidation und damit eine Imidyl‐radikalische elektronische Struktur für 3. Die Insertion einer verfügbaren NHC‐Einheit in den Imidoliganden in 2 ergibt innerhalb 12 Stunden das CoI‐N‐heterocyclische Imin 4. Im Gegensatz dazu dauert es nur eine halbe Stunde, bis sich 3 in das CoII‐Kongener 5 umsetzt. Es wurde weiterhin festgestellt, dass die Insertionsreaktion von 2 zu 4 durch einen nukleophilen Angriff des Imidoliganden am NHC erfolgt, wohingegen sich 3 zu 5 durch einen nukleophilen Angriff des NHCs am elektrophilen Imidylliganden umsetzt. Der Reaktivitätswechsel bei der Oxidation von 2 zu 3 bestätigt eine Umpolung des Imidoliganden.
Ein direkter Zugang zu einem endständigen CoIII‐Imidylradikalkomplex wurde durch die Einelektronenoxidation eines terminalen CoIII‐Imidoausgangskomplexes erreicht. Die Oxidation des endständigen CoIII‐Imidos zu seinem Imidyl‐Redoxisomer erleichtert die intramolekulare migratorische Insertionsreaktion des Imidos mit einem NHC‐Liganden durch einen Wechsel des Mechanismus mittels Umpolung des Imidoliganden.
We consider superconductivity in the presence of impurities in a two-band model suited for the description of iron-based superconductors. We analyze the effect of interband scattering processes on ...superconductivity, allowing for orbital, i.e., nonspin-magnetic but time-reversal symmetry-breaking impurities. Pair breaking in such systems is described by a nontrivial phase in an interband-scattering matrix element. We find that the transition temperature of conventional superconductors can be suppressed due to interband scattering, whereas unconventional superconductors may be unaffected. We also discuss the stability of density wave phases in the presence of impurities. As an example, we consider impurities associated with imaginary charge density waves that are of interest for iron-based superconductors.
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