bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlation of the Kennedy Osteitis Score to clinico‐histologic features of chronic rhinosinusitis
Authors: Snidvongs Kornkiat , McLachlan Rohan , Sacks Raymond , Earls Peter , Harvey Richard J. 
Published: November 2012

BackgroundOsteitis is a feature of chronic rhinosinusitis (CRS) and often associated with recalcitrant disease. Radiological characteristics of osteitic sinus changes are commonly reported in practice but the clinical and pathologic significance is poorly defined. The objective of this study was to correlate the Kennedy Osteitis Score (KOS) to clinico‐histologic features of CRS.MethodsA cross‐sectional study of CRS patients undergoing sinus surgery was conducted. Osteitis was scored radiologically using the KOS. Associations between osteitis and histopathology, symptoms, 22‐item Sino‐Nasal Outcomes Test (SNOT‐22), endoscopy, computed tomography (CT) mucosal score, and seromarkers were assessed. Interobserver correlation coefficient was performed. Additionally, the KOS was correlated to an alternate Global Osteitis Score.ResultsA total of 88 patients were assessed (45.5% female, age 50.3 ± 13.6 years); 45 (51.1%) patients had osteitis. Patients with KOS >0, had greater endoscopy score (6.1 ± 2.9 vs 4.4 ± 3.6, p = 0.03) and CT score (14.0 ± 6.0 vs 10.1 ± 5.7, p < 0.01) than those without osteitis. There was no difference in symptom score (2.4 ± 1.3 vs 2.4 ± 1.1, p = 0.89) and SNOT‐22 (2.0 ± 1.0 vs 1.9 ± 1.1, p = 0.56) in patients with and without osteitis. KOS was higher in patients with tissue eosinophilia >10/high‐power field (HPF) (median 3.0 [IQR, 1.0–5.3] vs 0.0 [0.0–4.0], p = 0.03) and serum eosinophilia >0.3 × 109/L (4.0 [2.0–7.0] vs 1.0 [0.0–4.0], p < 0.01). Importantly, this was also true for those without prior surgery. The interobserver correlation coefficient was good (R = 0.86, p < 0.001). There was a significant correlation between the KOS and the Global Osteitis Score (R = 0.93, p < 0.001).ConclusionThe KOS is a simple, easy, and reproducible scale in assessing osteitic bones in patients with CRS and can predict measures of severity in eosinophilic rhinosinusitis.
Noninvasive Staphylococcus aureus biofilm determination in chronic rhinosinusitis by detecting the exopolysaccharide matrix component poly‐N‐acetylglucosamine
Authors: Foreman Andrew , Jervis‐Bardy Josh , Boase Samuel J. , Tan Lorwai , Wormald Peter‐John 
Published: November 2012

BackgroundThe role that bacterial biofilms might play in recalcitrant forms of chronic rhinosinusitis (CRS) is increasingly being recognized. However, the detection of bacteria existing in this form, using standard culture, is limited by their unique metabolically inactive properties. All current biofilm diagnostic modalities require invasive mucosal biopsies, which limit their use to the operating theatre.MethodsTwenty CRS patients and 5 controls were enrolled in a prospective study to assess the feasibility of noninvasively diagnosing S. aureus biofilms by detecting the biofilm matrix polysaccharide poly‐N‐acetylglucosamine (PNAG). An immunofluorescence protocol was developed for PNAG detection and compared with both standard microbiological cultures and fluorescence in situ hybridization (FISH).ResultsThirteen of 20 CRS patients had evidence of S. aureus biofilm formation using FISH. Of these, 12 had detectable PNAG. Interestingly none of the S. aureus FISH‐negative patients were PNAG‐positive despite the presence of coagulase‐negative Staphylococci biofilms, some of which may exhibit PNAG in their pathogenic forms. The development of a noninvasive S. aureus biofilm diagnostic test provides a reliable means to identify a high‐risk group of CRS patients who harbor S. aureus biofilms. The ability to be used outside of the perioperative period to assess surgical efficacy, guide management, and evaluate new treatment modalities provides a significant advance in this field of research and clinical practice.ConclusionThis study has confirmed the feasibility of noninvasive detection of S. aureus biofilms with a simple test that produces results comparable to the more invasive methods that are currently relied upon.
Numerical investigation of the effect of the heterogeneous reaction model on the thermal behavior of pulverized coal combustion
Authors: Nozawa Sohey , Matsushita Yohsuke 
Published: November 2012

ABSTRACTTo achieve high efficiency in pulverized coal combustion furnace and burner, the detailed estimation of the burn‐off time and thermal behavior of pulverized coal particles is important. The volume reaction and unreacted core models have been employed as solid–gas reaction model for a pulverized coal particle. Moreover, the possibility that the heat of reaction generated on the particle surface does not fully contribute as heating source to the coal particle should be considered. In this study, the heat and mass transfer around a single pulverized coal char particle exposed to a simplified heating environment are numerically analyzed to investigate the influence of the different coal ranks in their reactivity, coal char particle diameter, and reaction models for the burn‐off time and thermal behavior of the pulverized coal particle. From the sensitivity analysis of the reaction models for the burn‐off time, the importance of model selection when dealing the coal char particle with high reaction rates is indicated. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Squaric Acid Mediated Chemoselective PEGylation of Proteins: Reactivity of Single‐Step‐Activated α‐Amino Poly(ethylene glycol)s
Authors: Dingels Carsten , Wurm Frederik , Wagner Manfred , Klok Harm‐Anton , Frey Holger 
Published: November 2012

AbstractThe covalent attachment of poly(ethylene glycol) (PEG) to therapeutically active proteins (PEGylation) has become an important method to deal with the pharmacological difficulties of these polypeptides, such as short body‐residence times and immunogenicity. However, the derivatives of PEG used for PEGylation lack further functional groups that would allow the addition of targeting or labeling moieties. Squaric acid diethyl ester was used for the chemoselective single‐step activation of poly(ethylene glycol)s into the respective ester amides. The resultant selective protein‐reactive poly(ethylene glycol)s were investigated with respect to their selectivity towards amino acid residues in bovine serum albumin (as a model protein). The presented procedure relies on a robust two‐step protocol and was found to be selective towards lysine residues; the activated polyethers are efficient and stoichiometric PEGylation agents with a remarkable hydrolytic stability over a period of several days. By adjusting the pD value of the conjugation mixture, the chemoselectivity of the activated PEGs towards the α‐ and ε‐amino groups of lysine methyl ester was effectively changed.
Boronium‐Cation‐Based Ionic Liquids as Hypergolic Fluids
Authors: Wang Kai , Zhang Yanqiang , Chand Deepak , Parrish Damon A. , Shreeve Jean'ne M. 
Published: November 2012

AbstractTwo series of boronium‐cation‐based ionic liquids were prepared and fully characterized by 1H, 13C, and 11B NMR and infrared spectroscopy, differential scanning calorimetry (DSC), and elemental analysis. The structure of bis(1‐methyl‐1H‐imidazole‐3‐yl)dihydroboronium dicyanoborohydride (5 a) was determined by single‐crystal X‐ray diffraction. The densities of these ionic liquids range from 1.05 to 1.28 g cm−3, and the heats of formation, predicted on the basis of Gaussian 03 calculations, fall between −164.6 and 430.5 kJ mol−1. Compound 5 b, bis(1‐allyl‐1H‐imidazole‐3‐yl)dihydroboronium dicyanoborohydride, exhibits the lowest viscosity (35 mPa s) and shortest ignition‐delay time (14 ms) in combination with 100 % HNO3.
IR‐Monitored Photolysis of CO‐Inhibited Nitrogenase: A Major EPR‐Silent Species with Coupled Terminal CO Ligands
Authors: Yan Lifen , Pelmenschikov Vladimir , Dapper Christie H. , Scott Aubrey D. , Newton William E. , Cramer Stephen P. 
Published: November 2012

AbstractFourier transform infrared spectroscopy (FTIR) was used to observe the photolysis and recombination of a new EPR‐silent CO‐inhibited form of α‐H195Q nitrogenase from Azotobacter vinelandii. Photolysis at 4 K reveals a strong negative IR difference band at $\tilde \nu $=1938 cm−1, along with a weaker negative feature at 1911 cm−1. These bands and the associated chemical species have both been assigned the label “Hi‐3”. A positive band at $\tilde \nu $=1921 cm−1 was assigned to the “Lo‐3” photoproduct. By using an isotopic mixture of 12C 16O and 13C 18O, we show that the Hi‐3 bands arise from coupling of two similar CO oscillators with one uncoupled frequency at approximately $\tilde \nu $=1917 cm−1. Although in previous studies Lo‐3 was not observed to recombine, by extending the observation range to 200–240 K, we found that recombination to Hi‐3 does indeed occur, with an activation energy of approximately 6.5 kJ mol−1. The frequencies of the Hi‐3 bands suggest terminal CO ligation. This hypothesis was tested with DFT calculations on models with terminal CO ligands on Fe2 and Fe6 of the FeMo‐cofactor. An S=0 model with both CO ligands in exo positions predicts symmetric and asymmetric stretches at $\tilde \nu $=1938 and 1909 cm−1, respectively, with relative band intensities of about 3.5:1, which is in good agreement with experiment. From the observed IR intensities, Hi‐3 was found to be present at a concentration about equal to that of the EPR‐active Hi‐1 species. The relevance of Hi‐3 to the nitrogenase catalytic mechanism and its recently discovered Fischer–Tropsch chemistry is discussed.
Chiral Supramolecular Switches Based on (R)‐Binaphthalene–Bipyridinium Guests and Cucurbituril Hosts
Authors: Gao Chao , Silvi Serena , Ma Xiang , Tian He , Credi Alberto , Venturi Margherita 
Published: November 2012

AbstractWe designed and synthesized the three molecular tweezers1 a–c4+containing an electron acceptor 4,4′‐bipyridinium (BPY2+) unit in each of the two arms and an (R)‐2,2′‐dioxy‐1,1′‐binaphthyl (BIN) unit that plays the role of chiral centre and the hinge of the structure. Each BPY2+unit is connected to the BIN hinge by an alkyl chain formed by two‐ (1 a4+), four‐ (1 b4+), or six‐CH2(1 c4+) groups. The behavior of1 a–c4+upon chemical or photochemical reduction in the absence and in the presence of cucurbit[8]uril (CB[8]) or cucurbit[7]uril (CB[7]) as macrocyclic hosts for the bipyridinium units has been studied in aqueous solution. A detailed analysis of the UV/Vis absorption and circular dichroism (CD) spectra shows that the helicity of the BIN unit can be reversibly modulated by reduction of the BPY2+units, or by association with cucurbiturils. Upon reduction of1 a–c4+compounds, the formed BPY+.units undergo intramolecular dimerization with a concomitant change in the BIN dihedral angle, which depends on the length of the alkyl spacers. The alkyl linkers also play an important role in association to cucurbiturils. Compound1 a4+, because of its short carbon chain, associates to the bulky CB[8] in a 1:1 ratio, whereas in the case of the smaller host compound CB[7] a 1:2 complex is obtained. Compounds1 b4+and1 c4+, which have longer linkers, associate to two cucurbiturils regardless of their sizes. In all cases, association with CB[8] causes an increase of the BIN dihedral angle, whereas the formation of CB[7] complexes causes an angle decrease. Reduction of the CB[8] complexes results in an enhancement of the BPY+.dimerization with respect to free1 a–c4+and causes a noticeable decrease of the BIN dihedral angle, because the BPY+.units of the two arms have to enter into the same macrocycle. The dimer formation in the CB[8] complexes characterized by a 1:2 ratio implies the release of one macrocycle showing that the binding stoichiometry of these host–guest complexes can be switched from 1:2 to 1:1 by changing the redox state of the guest. When the reduction is performed on the CB[7] complexes, dimer formation is totally inhibited, as expected because the CB[7] cavity cannot host two BPY+.units.
Total Synthesis of (−)‐Zampanolide and Structure–Activity Relationship Studies on (−)‐Dactylolide Derivatives
Authors: Zurwerra Didier , Glaus Florian , Betschart Leo , Schuster Julia , Gertsch Jürg , Ganci Walter , Altmann Karl‐Heinz 
Published: November 2012

AbstractA new total synthesis of the marine macrolide (−)‐zampanolide (1) and the structurally and stereochemically related non‐natural levorotatory enantiomer of (+)‐dactylolide (2), that is, ent‐2, has been developed. The synthesis features a high‐yielding, selective intramolecular Horner–Wadsworth–Emmons (HWE) reaction to close the 20‐membered macrolactone ring of 1 and ent‐2. The β‐keto phosphonate/aldehyde precursor for the ring‐closure reaction was obtained by esterification of a ω‐diethylphosphono carboxylic acid fragment and a secondary alcohol fragment incorporating the THP ring that is embedded in the macrocyclic core structure of 1 and ent‐2. THP ring formation was accomplished through a segment coupling Prins‐type cyclization. Employing the same overall strategy, 13‐desmethylene‐ent‐2 as well as the monocyclic desTHP derivatives of 1 and ent‐2 were prepared. Synthetic 1 inhibited human cancer cell growth in vitro with nM IC50 values, while ent‐2, which lacks the diene‐containing hemiaminal‐linked side chain of 1, is 25‐ to 260‐fold less active. 13‐Desmethylene‐ent‐2 as well as the reduced versions of ent‐2 and 13‐desmethylene‐ent‐2 all showed similar cellular activity as ent‐2 itself. The same activity level was attained by the monocyclic desTHP derivative of 1. Oxidation of the aldehyde functionality of ent‐2 gave a carboxylic acid that was converted into the corresponding N‐hexyl amide. The latter showed only μM antiproliferative activity, thus being several hundred‐fold less potent than 1.
Mixed (PS/PO)‐Stabilized Geminal Dianion: Facile Diastereoselective Intramolecular CH Activations by a Related Ruthenium–Carbene Complex
Authors: Heuclin Hadrien , Le Goff Xavier F. , Mézailles Nicolas 
Published: November 2012

AbstractA new unsymmetrical geminal dianion that contained both a phosphine oxide moiety and a phosphine sulfide moiety has been synthesized. Its reactivity towards RuII was explored, which led to the formation of a highly reactive carbene complex that evolved at room temperature to yield a kinetic orthometalated RuII complex through CH activation of the phenyl group of the phosphine oxide moiety. This insertion was found to be thermally reversible and a second CH insertion occurred at a phenyl group of the phosphine sulfide moiety to form the thermodynamic orthometalated RuII complex in a diastereospecific manner. DFT calculations fully rationalized the experimental findings in terms of the relative energies of the kinetic and thermodynamic products and allowed the mechanism of this process to be fully understood.
Copper, BDNF and Its N‐terminal Domain: Inorganic Features and Biological Perspectives
Authors: Travaglia Alessio , La Mendola Diego , Magrì Antonio , Nicoletti Vincenzo Giuseppe , Pietropaolo Adriana , Rizzarelli Enrico 
Published: November 2012

AbstractBrain‐derived neurotrophic factor (BDNF) is a neurotrophin that influences development, maintenance, survival, and synaptic plasticity of central and peripheral nervous systems. Altered BDNF signaling is involved in several neurodegenerative disorders including Alzheimer’s disease. Metal ions may influence the BDNF activity and it is well known that the alteration of Cu2+ homeostasis is a prominent factor in the development of neurological pathologies. The N‐terminal domain of BDNF represents the recognition site of its specific receptor TrkB, and metal ions interaction with this protein domain may influence the protein/receptor interaction. In spite of this, no data inherent the interaction of BDNF with Cu2+ ions has been reported up to now. Cu2+ complexes of the peptide fragment BDNF(1–12) encompassing the sequence 1–12 of N‐terminal domain of human BDNF protein were characterized by means of potentiometry, spectroscopic methods (UV/Vis, CD, EPR), parallel tempering simulations and DFT‐geometry optimizations. Coordination features of the acetylated form, Ac‐BDNF(1–12), were also characterized to understand the involvement of the terminal amino group. Whereas, an analogous peptide, BDNF(1–12)D3N, in which the aspartate residue was substituted by an asparagine, was synthesized to provide evidence on the possible role of carboxylate group in Cu2+ coordination. The results demonstrated that the amino group is involved in metal binding and the metal coordination environment of the predominant complex species at physiological pH consisted of one amino group, two amide nitrogen atoms, and one carboxylate group. Noteworthy, a strong decrease of the proliferative activity of both BDNF(1–12) and the whole protein on a SHSY5Y neuroblastoma cell line was found after treatment in the presence of Cu2+. The effect of metal addition is opposite to that observed for the analogous fragment of nerve growth factor (NGF) protein, highlighting the role of specific domains, and suggesting that Cu2+ may drive different pathways for the BDNF and NGF in physiological as well as pathological conditions.
Flexible, Scalable and Configurable Single‐Use Systems for Biopharmaceutical Research and Manufacture
Authors: Szarafinski Detlev 
Published: November 2012

AbstractSingle‐use (SU) components are a common standard in the biopharmaceutical industry. Mixing units for buffer and media preparation, bioreactors for cell cultivation, bags for storage of liquids etc. have meanwhile become integral SU components within many biopharmaceutical manufacturing processes. However, there is still a lack of SU systems incorporating multiple process steps into a SU system which constitutes a dedicated unit operation for research and development and production of e.g. monoclonal antibodies. The FlexAct® approach fills this gap and has been developed to supply scalable and configurable SU systems for upstream‐ and downstream processing. Typical unit operations are, e.g., buffer and media preparation, cell harvest, virus inactivation and ultrafiltration.
How is 68Ga Labeling of Macrocyclic Chelators Influenced by Metal Ion Contaminants in 68Ge/68Ga Generator Eluates?
Authors: Šimeček Jakub , Hermann Petr , Wester Hans‐Jürgen , Notni Johannes 
Published: November 2012

AbstractTo assess the influence of Zn2+, Cu2+, Fe3+, Al3+, TiIV, and SnIV on incorporation of 68Ga3+ into pendant‐arm macrocyclic chelators, the 68Ga labeling of 1,4,7‐triazacyclononane‐1,4,7‐triacetic acid (NOTA), 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid (DOTA), 1,4,7‐triazacyclononane‐1,4,7‐tris[methyl(2‐carboxyethyl)phosphinic acid]) (TRAP), and 1,4,7‐triazacyclononane‐1‐[methyl(2‐carboxyethyl)phosphinic acid]‐4,7‐bis[methyl(2‐hydroxymethyl)phosphinic acid] (NOPO), as well as their peptide conjugates, was investigated in the presence of varying concentrations of these metal ions. The 68Ga labeling yield for carboxylate‐type chelators NOTA and DOTA is decreased at lower metal ion contaminant concentrations compared with phosphinate‐type chelators TRAP and NOPO. The latter are able to rapidly exchange coordinated ZnII with 68Ga3+, as confirmed by mass spectrometry and 31P NMR spectroscopy. 68Ga labeling of ZnII complexes of TRAP and NOPO proceeds as efficient as labeling of neat NOTA; this applies also to the corresponding peptide conjugates of these chelators. This behavior results in substantially improved selectivity for Ga3+ and, therefore, in more robust and reliable 68Ga labeling procedures. In addition, none of the investigated chelators binds 68Ge, rendering post‐labeling purification protocols, for example, solid‐phase extraction, a reliable means of removal of 68Ge contamination from 68Ga radiopharmaceuticals.
Isolation of erythrocytes infected with viable early stages of Plasmodium falciparum by flow cytometry
Authors: Philipp Stephan , Oberg Hans‐Heinrich , Janssen Ottmar , Leippe Matthias , Gelhaus Christoph 
Published: November 2012

AbstractThe erythrocytic life cycle of Plasmodium falciparum is highly associated with severe clinical symptoms of malaria that causes hundreds of thousands of death each year. The parasite develops within human erythrocytes leading to the disruption of the infected red blood cell (iRBC) prior to the start of a new cycle of erythrocyte infection. Emerging mechanisms of resistance against antimalarial drugs require improved knowledge about parasite's blood stages to facilitate new alternative antimalarial strategies. For the analysis of young blood stages of Plasmodium at the molecular level, the isolation of ring stages is essential. However, early stages can hardly be separated from both, late stages and non‐infected red blood cells using conventional methods. Here, iRBCs were stained with the DNA‐binding dyes Vybrant® DyeCycle™ Violet and SYBR® Green I. Subsequently, cells were subjected to flow‐cytometric analysis. This enabled the discrimination of early stage iRBCs as well as late‐stage iRBCs from non‐infected erythrocytes and the properties of the used dyes were evaluated. Moreover, early stage iRBCs were isolated with high purity (>98%) by FACS. Subsequently, development of sorted early stages of the parasite was monitored over time and compared with control cultures. The described flow cytometry method, based on staining with Vybrant DyeCycle Violet, allows the isolation of viable ring stages of the malarial agent P. falciparum, and thereby provides the basis for new, broad‐range molecular investigations of the parasite. © 2012 International Society for Advancement of Cytometry
Dinuclear Macrocyclic Palladium Dithiocarbamates Derived from the Homologous Series of Aliphatic 1,x‐Diamines (x = 4–10)
Authors: Torres‐Huerta Aarón , Höpfl Herbert , Tlahuext Hugo , Hernández‐Ahuactzi Irán F. , Sánchez Mario , Reyes‐Martínez Reyna , Morales‐Morales David 
Published: November 2012

AbstractSeven dinuclear macrocyclic palladium(II) dithiocarbamates have been prepared from a homologous series of aliphatic 1,x‐diamines (x = 4–10); the objective was to vary systematically the size of the cavity. The resulting complexes were characterized by IR and NMR (1H, 13C) spectroscopy, high‐resolution FAB mass spectrometry, and in one case additionally by single‐crystal X‐ray diffraction analysis. Geometry‐optimizations using the B3LYP functional in combination with the def2‐SVP basis set were performed for the complete series of 22‐ to 36‐membered macrocycles and showed that these can be divided into two classes. Palladium(II) dithiocarbamates with an even number of methylene spacer groups yield macrocycles of rectangular shape with overall dimensions that vary from 6.0 × 14.5 × 12.7 to 6.0 × 15.7 × 19.9 Å3, whereas an odd number generates hexagon‐shaped assemblies with overall dimensions in the range 5.0 × 16.3 × 13.0 to 6.0 × 21.1 × 18.7 Å3. The computational analysis ruled out the possibility that monomeric structures had formed and indicated that for the creation of strain‐free mononuclear macrocyclic structures at least 14 methylene groups are required in the spacer.