bluuebunny/crossref_metadata_2025_split huggingface dataset:
Are viruses a source of new protein folds for organisms? – Virosphere structure space and evolution
Authors: Abroi Aare , Gough Julian 
Published: June 2011

AbstractA crucially important part of the biosphere – the virosphere – is too often overlooked. Inclusion of the virosphere into the global picture of protein structure space reveals that 63 protein domain superfamilies in viruses do not have any structural and evolutionary relatives in modern cellular organisms. More than half of these have functions which are not virus‐specific and thus might be a source of new folds and functions for cellular life. The number of viruses on the planet exceeds that of cells by an order of magnitude and viruses evolve up to six orders of magnitude faster. As a result, cellular species are subject to a constitutive ‘flow‐through’ of new viral genetic material. Due to this and the relaxed evolutionary constraints in viruses, the transfer of domains between host‐to‐virus could be a mechanism for accelerated protein evolution. The virosphere could be an engine for the genesis of protein structures, and may even have been so before the last universal common ancestor of cellular life.
Polymorphisms in the toll-like receptor 9 gene associated with sepsis and multiple organ dysfunction after major blunt trauma
Authors: Chen K-H , Zeng L , Gu W , Zhou J , Du D-Y , Jiang J-X 
Published: June 2011

Abstract

Background
Toll-like receptor (TLR) 9 is the pattern recognition receptor for microbial DNA. Genetic variation within pattern recognition receptors for bacterial endotoxin and exotoxin has been shown to be associated with the risk of sepsis and organ dysfunction in critical illness. However, little is known about the clinical relevance of TLR9 gene polymorphisms in critical illness.

Methods
A total of 557 patients with major blunt trauma were included in the study. Genetic variation data for the entire TLR9 gene were obtained from the HapMap Project. The genotypes of TLR9 gene polymorphisms were determined using a pyrosequencing method. Whole peripheral blood samples obtained immediately after admission were stimulated with bacterial DNA and production of tumour necrosis factor (TNF) α was then determined. Sepsis morbidity rate and multiple organ dysfunction (MOD) scores were assessed.

Results
Of five single-nucleotide polymorphisms (SNPs) genotyped, four (rs187084, rs352139, rs352140 and rs352162) existed as common SNPs and were in strong linkage disequilibrium. Both rs187084 and rs352162 were significantly associated with TNF-α production by peripheral blood leucocytes in response to bacterial DNA stimulation and a higher sepsis morbidity rate in patients with major trauma. In addition, the rs352162 polymorphism was significantly associated with MOD scores, whereas rs187084 showed a trend to be associated with MOD score.

Conclusion
TLR9 polymorphisms rs187084 and rs352162 might be used to provide relevant risk estimates for the development of sepsis and MOD in patients with major trauma.
Five-year results of a randomized clinical trial comparing endovenous laser ablation with cryostripping for great saphenous varicose veins
Authors: Disselhoff B C V M , der Kinderen D J , Kelder J C , Moll F L 
Published: June 2011

Abstract

Background
This was the long-term follow-up of a previously reported randomized clinical trial comparing endovenous laser ablation (EVLA) with cryostripping for great saphenous varicose veins.

Methods
A total of 120 patients with great saphenous varicose veins were randomized 1:1 to EVLA or cryostripping. Principal outcome measures were freedom from incompetence or neovascularization on duplex imaging, and improvement in Venous Clinical Severity Score (VCSS) and Aberdeen Varicose Vein Severity Score (AVVSS) 5 years after treatment.

Results
Life-table analysis showed freedom from duplex-derived incompetence and neovascularization at 5 years in 62 (95 per cent confidence interval 50 to 76) per cent after EVLA and in 51 (39 to 66) per cent after cryostripping (P = 0·246). Neovascularization was more common after cryostripping, but incompetent tributaries were more common after EVLA. VCSS and AVVSS values improved significantly after treatment in both groups, and were maintained for 5 years, but with no significant difference between the groups.

Conclusion
In this study, no significant difference was demonstrated in late outcome after EVLA or cryostripping in patients with great saphenous varicose veins. Registration number: ISRCTN33832691 (http://www.controlled-trials.com).
Hydride Mobility in Trinuclear Sulfido Clusters with the Core [Rh3(μ‐H)(μ3‐S)2]: Molecular Models for Hydrogen Migration on Metal Sulfide Hydrotreating Catalysts
Authors: Jiménez M. Victoria , Lahoz Fernando J. , Lukešová Lenka , Miranda José R. , Modrego Francisco J. , Nguyen Duc H. , Oro Luis A. , Pérez‐Torrente Jesús J. 
Published: June 2011

AbstractThe treatment of [{Rh(μ‐SH){P(OPh)3}2}2] with [{M(μ‐Cl)(diolef)}2] (diolef=diolefin) in the presence of NEt3 affords the hydrido–sulfido clusters [Rh3(μ‐H)(μ3‐S)2(diolef){P(OPh)3}4] (diolef=1,5‐cyclooctadiene (cod) for 1, 2,5‐norbornadiene (nbd) for 2, and tetrafluorobenzo[5,6]bicyclo[2.2.2]octa‐2,5,7‐triene (tfb) for 3) and [Rh2Ir(μ‐H)(μ3‐S)2(cod){P(OPh)3}4] (4). Cluster 1 can be also obtained by treating [{Rh(μ‐SH){P(OPh)3}2}2] with [{Rh(μ‐OMe)(cod)}2], although the main product of the reaction with [{Ir(μ‐OMe)(cod)}2] was [RhIr2(μ‐H)(μ3‐S)2(cod)2{P(OPh)3}2] (5). The molecular structures of clusters 1 and 4 have been determined by X‐ray diffraction methods. The deprotonation of a hydrosulfido ligand in [{Rh(μ‐SH)(CO)(PPh3)}2] by [M(acac)(diolef)] (acac=acetylacetonate) results in the formation of hydrido–sulfido clusters [Rh3(μ‐H)(μ3‐S)2(CO)2(diolef)(PPh3)2] (diolef=cod for 6, nbd for 7) and [Rh2Ir(μ‐H)(μ3‐S)2(CO)2(cod)(PPh3)2] (8). Clusters 1–3 and 5 exist in solution as two interconverting isomers with the bridging hydride ligand at different edges. Cluster 8 exists as three isomers that arise from the disposition of the PPh3 ligands in the cluster (cis and trans) and the location of the hydride ligand. The dynamic behaviour of clusters with bulky triphenylphosphite ligands, which involves hydrogen migration from rhodium to sulfur with a switch from hydride to proton character, is significant to understand hydrogen diffusion on the surface of metal sulfide hydrotreating catalysts.
Two Cu21 Clusters with Pseudo‐D3 Symmetry Derived from the D‐Saccharate Pentaanion, C6H5O85−
Authors: Abrahams Brendan F. , McCormick Laura J. , Moubaraki Boujemaa , Murray Keith S. , Robson Richard , Waters Tom 
Published: June 2011

AbstractThe combination of Cu(NO3)2, potassium hydrogen saccharate (KC6H9O8) and 1,10‐phenanthroline (phen) yields a pair of chiral cluster compounds, each with composition Cu21(C6H5O8)6(phen)12(NO3)12⋅solvate. One of the compounds forms as orthorhombic crystals, while the other forms cubic crystals. Each of the clusters has D3 or approximate D3 symmetry, but the arrangement of the saccharate ion in the clusters is quite different in the two cases. The clusters in the cubic form interact with neighbouring clusters through face‐to‐face π interactions involving the phen ligands, an association that leads to the generation of very large solvent‐filled spaces in the crystal structure. In contrast the clusters in the orthorhombic form are much more densely packed. At the centre of each cluster that crystallises in the orthorhombic form is a nitrate anion that binds to six CuII centres. ESI mass spectral studies indicate that the Cu21 clusters exist in solution. Solid‐state magnetic studies of the cubic form of Cu21 show that antiferromagnetic coupling occurs to leave a non‐zero‐spin ground state, and comparisons are made to the magnetic data for other large CuII clusters.
Design, Synthesis, ADME Properties, and Pharmacological Activities of β‐Alanyl‐D‐histidine (D‐Carnosine) Prodrugs with Improved Bioavailability
Authors: Orioli Marica , Vistoli Giulio , Regazzoni Luca , Pedretti Alessandro , Lapolla Annunziata , Rossoni Giuseppe , Canevotti Renato , Gamberoni Luca , Previtali Massimo , Carini Marina , Aldini Giancarlo 
Published: June 2011

Abstractβ‐Alanyl‐D‐histidine (D‐CAR, the enantiomer of the natural dipeptide carnosine) is a selective and potent sequestering agent of reactive carbonyl species (RCS) that is stable against carnosinase, but is poorly absorbed in the gastrointestinal tract. Herein we report a drug discovery approach aimed at increasing the oral bioavailability of D‐CAR. In our study we designed, synthesized, and evaluated a series of novel lipophilic D‐CAR prodrugs. The considered prodrugs can be divided into two categories: 1) derivatives with both terminal groups modified, in which the carboxyl terminus is always esterified while the amino terminus is protected by an amidic (N‐acetyl derivatives) or a carbamate (ethyloxy or benzyloxy derivatives) function; 2) derivatives with only one terminus modified, which can be alkyl esters as well as amidic or carbamate derivatives. The prodrugs were designed considering their expected lipophilicity and their hydrolysis predicted by docking simulations on the most important human carboxylesterase (hCES1). The stability and metabolic profile of the prodrugs were studied by incubating them with rat and human serum and liver fractions. The octyl ester of D‐CAR (compound 13) was chosen as a candidate for further pharmacological studies due to its rapid hydrolysis to the bioactive metabolite in vitro. Pharmacokinetic studies in rats confirmed the in vitro data and demonstrated that the oral bioavailability of D‐CAR is increased 2.6‐fold if given as an octyl ester relative to D‐CAR. Compound 13 was then found to dose‐dependently (at daily doses of 3 and 30 mg kg−1 equivalent of D‐CAR) decrease the development of hypertension and dyslipidemia, to restore renal functions of Zucker fa/fa obese rats, and to inhibit the carbonylation process (AGEs and pentosidine) as well as oxidative stress (urinary 8‐epi‐prostaglandin F2α and nitrotyrosine). A plausible mechanism underlying the protective effects of 13 is RCS sequestration, as evidenced by the significant increase in the level of adduct between CAR and 4‐hydroxy‐trans‐2‐nonenal (HNE, the main RCS generated by lipid oxidation) in the urine of treated animals.
Alternating‐Current Measurements in Scanning Electrochemical Microscopy, Part 1: Principle and Theory
Authors: Trinh Dao , Keddam Michel , Novoa Xosé R. , Vivier Vincent 
Published: June 2011

AbstractThe development of the scanning electrochemical microscope in ac mode is presented from both experimental and theoretical point of views. The experiments are performed with the ferri/ferrocyanide redox mediator as model system. Based on analysis of the frequency‐dependent collection efficiency, diffusion between the probe and the substrate is investigated, and analysis of time constants allows evaluation of the size of the sensing area under investigation. The experimental results are in good agreement with numerical simulations.
Catalytic Production of Conjugated Fatty Acids and Oils
Authors: Philippaerts An , Goossens Steven , Jacobs Pierre A. , Sels Bert F. 
Published: June 2011

AbstractThe reactive double bonds in conjugated vegetable oils are of high interest in industry. Traditionally, conjugated vegetable oils are added to paints, varnishes, and inks to improve their drying properties, while recently there is an increased interest in their use in the production of bioplastics. Besides the industrial applications, also food manufactures are interested in conjugated vegetable oils due to their various positive health effects. While the isomer type is less important for their industrial purposes, the beneficial health effects are mainly associated with the c9,t11, t10,c12 and t9,t11 CLA isomers. The production of CLA‐enriched oils as additives in functional foods thus requires a high CLA isomer selectivity. Currently, CLAs are produced by conjugation of oils high in linoleic acid, for example soybean and safflower oil, using homogeneous bases. Although high CLA productivities and very high isomer selectivities are obtained, this process faces many ecological drawbacks. Moreover, CLA‐enriched oils can not be produced directly with the homogeneous bases. Literature reports describe many catalytic processes to conjugate linoleic acid, linoleic acid methyl ester, and vegetable oils rich in linoleic acid: biocatalysts, for example enzymes and cells; metal catalysts, for example homogeneous metal complexes and heterogeneous catalysts; and photocatalysts. This Review discusses state‐of‐the‐art catalytic processes in comparison with some new catalytic production routes. For each category of catalytic process, the CLA productivities and the CLA isomer selectivity are compared. Heterogeneous catalysis seems the most attractive approach for CLA production due to its easy recovery process, provided that the competing hydrogenation reaction is limited and the CLA production rate competes with the current homogeneous base catalysis. The most important criteria to obtain high CLA productivity and isomer selectivity are (1) absence of a hydrogen donor, (2) absence of catalyst acidity, (3) high metal dispersion, and (4) highly accessible pore architecture.
Genome‐wide association studies (GWAS): impact on elucidating the aetiology of diabetes
Authors: Hakonarson Hakon , Grant Struan F. A. 
Published: June 2011

AbstractIt has proven to be challenging to isolate the genes underlying the genetic components conferring susceptibility to type 1 and type 2 diabetes. Unlike previous approaches, ‘genome‐wide association studies’ have extensively delivered on the promise of uncovering genetic determinants of complex diseases, with a number of novel disease‐associated variants being largely replicated by independent groups. This review provides an overview of these recent breakthroughs in the context of type 1 and type 2 diabetes, and outlines strategies on how these findings will be applied to impact clinical care for these two highly prevalent disorders. Copyright © 2011 John Wiley & Sons, Ltd.
Early viral replication in lymph nodes provides HIV with a means by which to escape NK‐cell‐mediated control
Authors: Luteijn Rutger , Sciaranghella Gaia , van Lunzen Jan , Nolting Anne , Dugast Anne‐Sophie , Ghebremichael Musie S. , Altfeld Marcus , Alter Galit 
Published: June 2011

AbstractAcute HIV infection is marked by dramatic viral replication associated with preferential replication within secondary lymphoid tissues, such as lymph nodes (LNs), that is rapidly but incompletely contained to a viral setpoint. Accumulating evidence supports a role for natural killer (NK) cells in the early control of HIV infection; however, little is known about the location of their antiviral control. Given that HIV replicates profusely in LNs during early infection, we sought to define whether changes occurred in the NK cell infiltrate within these sites during the first year of HIV infection. Surprisingly, NK cell numbers and distribution were unaltered during early HIV infection. LN NK cells expressed decreased inhibitory receptors, were more highly activated, and expressed elevated TRAIL, potentially conferring a superior capacity for NK cells to become activated and control infection. Most noticeably, KIR+ NK cells were rarely detected in the LN during HIV infection, associated with diminished migratory capacity in the setting of reduced expression of CX3CR1 and CXCR1. Thus, incomplete control of HIV viral replication during early disease may be due to the inefficient recruitment of KIR+ NK cells to this vulnerable site, providing HIV a niche where it can replicate unabated by early NK‐cell‐mediated innate pressure.
TLR activation enhances C5a‐induced pro‐inflammatory responses by negatively modulating the second C5a receptor, C5L2
Authors: Raby Anne‐Catherine , Holst Benjamin , Davies James , Colmont Chantal , Laumonnier Yves , Coles Barbara , Shah Sanjoy , Hall Judith , Topley Nicholas , Köhl Jörg , Morgan B. Paul , Labéta Mario O. 
Published: June 2011

AbstractTLR and complement activation ensures efficient clearance of infection. Previous studies documented synergism between TLRs and the receptor for the pro‐inflammatory complement peptide C5a (C5aR/CD88), and regulation of TLR‐induced pro‐inflammatory responses by C5aR, suggesting crosstalk between TLRs and C5aR. However, it is unclear whether and how TLRs modulate C5a‐induced pro‐inflammatory responses. We demonstrate a marked positive modulatory effect of TLR activation on cell sensitivity to C5a in vitro and ex vivo and identify an underlying mechanistic target. Pre‐exposure of PBMCs and whole blood to diverse TLR ligands or bacteria enhanced C5a‐induced pro‐inflammatory responses. This effect was not observed in TLR4 signalling‐deficient mice. TLR‐induced hypersensitivity to C5a did not result from C5aR upregulation or modulation of C5a‐induced Ca2+ mobilization. Rather, TLRs targeted another C5a receptor, C5L2 (acting as a negative modulator of C5aR), by reducing C5L2 activity. TLR‐induced hypersensitivity to C5a was mimicked by blocking C5L2 and was not observed in C5L2KO mice. Furthermore, TLR activation inhibited C5L2 expression upon C5a stimulation. These findings identify a novel pathway of crosstalk within the innate immune system that amplifies innate host defense at the TLR‐complement interface. Unravelling the mutually regulated activities of TLRs and complement may reveal new therapeutic avenues to control inflammation.
ZnII–2,2′:6′,2″‐Terpyridine‐Based Complex as Fluorescent Chemosensor for PPi, AMP and ADP
Authors: Das Priyadip , Ghosh Amrita , Kesharwani Manoj K. , Ramu Vadde , Ganguly Bishwajit , Das Amitava 
Published: June 2011

AbstractA new ZnII–2,2′:6′,2″‐terpyridine complex, derivatized with a coumarin moiety (L1Zn), acts as a fluorescent chemosensor for different biologically important phosphates like PPi, AMP and ADP in mixed aqueous media. Depending on the proportion of the aqueous fraction present in the solvent mixture, L1Zn shows a preference for different phosphate moieties at physiological pH. In an aqueous acetonitrile (2:3, v/v) medium this reagent shows a preference for AMP as compared to ADP, ATP and PPi. The binding affinities of L1Zn with different phosphate ions and associated shifts in the electronic spectra were rationalized by DFT calculations. Such an example of a receptor that is selective for AMP under physiological conditions is rare in the literature.
Guanidino‐Functionalised Aromatic Electron Donors at Work: Competing Hydrogen‐ and Electron‐Transfer Reactions in the Course of the Synthesis of Gold Acetylide Complexes
Authors: Emeljanenko Dimitri , Kaifer Elisabeth , Himmel Hans‐Jörg 
Published: June 2011

AbstractIn this work reactions between [AuCl(PPh3)] and HC≡CAr (Ar = phenyl, pyridinyl, biphenyl or p‐acetylphenyl) in the presence of the nitrogen base and organic electron donor1,2,4,5‐tetrakis(N,N′‐dimethyl‐N,N′‐ethyleneguanidino)benzene (1) were studied. Two different product types were isolated and characterised: the neutral AuI acetylides[Au(C≡CAr)PPh3] and the salts (1)[Au(C≡CAr)2]2. They can be easily separated from each other by crystallisation under different conditions. The yields strongly depend on the applied acetylene. While the first product type underlines the basic properties of 1, the second product type highlights its electron‐donor capacity. The experimental results indicate reduction of the C−H protons to H2 and two‐electron oxidation of 1. Thermal decomposition of (1)[Au(C≡CAr)2]2 (Ar = Ph) leads back to the neutral guanidine and Au nanoparticles (accompanied by oxidative coupling of the two acetylide ligands).
Tetrahedratic Mesophases, Ambidextrous Chiral Domains and Helical Superstructures Produced by Achiral 1,1′‐Disubstituted Ferrocene Derivatives
Authors: Kim Eun Ho , Kadkin Oleg Nikolaevich , Kim So Yeon , Choi Moon‐Gun 
Published: June 2011

AbstractA series of symmetrically and asymmetrically 1,1′‐disubstituted mesogenic ferrocene derivatives exhibiting nonconventional lamellar and nematic phases has been synthesized. Liquid‐crystal properties of these compounds were investigated by polarizing optical microscopy (POM), thermal analysis (DSC) and X‐ray scattering methods (XRD). XRD patterns and optical textures of the mesophases have a complex appearance, standing apart from the signatures of previously classified liquid crystals. The most important features of the new mesophases are their spontaneous separation into large macroscopic chiral domains of opposite handednesses, intricate helical and myelinic supramolecular structures and a few signs of possible optical biaxiality. A reasonable explanation of these findings can be drawn from the tetrahedral liquid crystal order. Free rotation of the cyclopentadiene rings in the ferrocene moiety around their normal axis makes viable bent conformations of the rod‐like molecules and further stabilization of the conformational enantiomers through assembly into tetrahedral molecular associates. Thus, fundamentally new types of mesophases arise from such a molecular arrangement. In addition, a nontrivial case of mixed packing of bent and nonbent molecules into columnar mesophases was detected in one of the symmetrically substituted ferrocene derivatives. Basic relationships between mesomorphic properties, supramolecular organization and chemical structures of the ferrocenomesogens have been outlined.
Oxo Boron Clusters and Their Open Frameworks
Authors: Lin Zhi‐En , Yang Guo‐Yu 
Published: June 2011

AbstractThis review article briefly summarizes the recent research advances in the field of crystalline oxo boron clusters and their open frameworks. By using different amine molecules and transition metal complexes or inorganic ions as the charge‐balancing agents, different oxo boron clusters, such as [B3O3(OH)4]–, [B4O5(OH)4]2–, [B5O6(OH)4]–, [B7O9(OH)5]2–, [B8O10(OH)6]2–, [B9O12(OH)6]3–, and [B14O20(OH)6]4– polyanions, have been successfully isolated and structurally characterized. These polyborate anions may act as the main building blocks to create new open‐framework compounds with layered and three‐dimensional structures. Odd ring channels and helical channels are noteworthy in open‐framework borate structures. Besides their traditional zeolitic properties, open‐framework borates exhibit interesting optical properties including photoluminescence and second harmonic generation, suggesting their potential applications in catalysis, nonlinear optics, display and lighting devices.