bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cognitive‐Performance Recovery of Alzheimer's Disease Model Mice by Modulation of Early Soluble Amyloidal Assemblies
Authors: Frydman‐Marom Anat , Rechter Meirav , Shefler Irit , Bram Yaron , Shalev Deborah E. , Gazit Ehud 
Published: November 2008

AbstractEin gezielt entworfener Oligomerisierungshemmer wechselwirkt mit frühen intermediären Aβ‐Aggregaten (Aβ=Amyloid‐β‐Polypeptid) und inhibiert so die Bildung der toxischen Oligomere, die die Alzheimer‐Krankheit verursachen. Das Bild zeigt das elektrostatische Potential der niederenergetischen Konformation des Dipeptid‐Inhibitors im Komplex mit Aβ.magnified image
Synthetic Study of (−)‐Norzoanthamine: Construction of the ABC Ring Moiety
Authors: Murata Yoshihisa , Yamashita Daisuke , Kitahara Katsushi , Minasako Yohei , Nakazaki Atsuo , Kobayashi Susumu 
Published: November 2008

AbstractAusgehend vom (−)‐Hajos‐Parrish‐Keton gelang eine hoch diastereoselektive Synthese des ABC‐Ringsystems von (−)‐Norzoanthamin (siehe Schema). Die drei quartären Kohlenstoffstereozentren am C‐Ring wurden durch eine 1,4‐Addition eingeführt, und eine intramolekulare Diels‐Alder‐Reaktion erzeugte das trans‐Decalin‐Gerüst für das AB‐Ringsystem.magnified image
Cognitive‐Performance Recovery of Alzheimer's Disease Model Mice by Modulation of Early Soluble Amyloidal Assemblies
Authors: Frydman‐Marom Anat , Rechter Meirav , Shefler Irit , Bram Yaron , Shalev Deborah E. , Gazit Ehud 
Published: November 2008

AbstractA rationally designed oligomerization inhibitor interacts with early intermediate assemblies of amyloid‐β polypeptide (Aβ) through the aromatic elements and inhibits their assembly into the toxic oligomers that cause Alzheimer's disease by a unique Cα‐methylation β‐breakage strategy. The electrostatic potential of the low‐energy conformation of the dipeptide inhibitor bound to Aβ is shown.magnified image
Incidence and risk factors of prosthetic joint infection after total hip or knee replacement in patients with rheumatoid arthritis
Authors: Bongartz Tim , Halligan Christine S. , Osmon Douglas R. , Reinalda Megan S. , Bamlet William R. , Crowson Cynthia S. , Hanssen Arlen D. , Matteson Eric L. 
Published: November 2008

AbstractObjectiveProsthetic joint infection is one of the most dreaded complications after total joint arthroplasty, a common procedure in patients with rheumatoid arthritis (RA). We conducted a study to evaluate potential risk factors of prosthetic joint infection and to clarify if RA is an independent predictor of this complication.MethodsThis study included all patients with RA who underwent total hip or knee replacement at the Mayo Clinic Rochester between January 1996 and June 2004. The association of potential risk factors with prosthetic joint infection was examined using Cox models. A matched cohort of patients with osteoarthritis (OA) was assembled to determine whether RA is an independent risk factor for prosthetic joint infection.ResultsWe identified 462 patients with RA who underwent a total of 657 hip or knee replacements. Overall, 23 (3.7%) joint arthroplasties were complicated by an infection during a mean ± SD followup of 4.3 ± 2.4 years. Revision arthroplasty (hazard ratio [HR] 2.99, 95% confidence interval [95% CI] 1.02–8.75) and a previous prosthetic joint infection of the replaced joint (HR 5.49, 95% CI 1.87–16.14) were significant predictors of postoperative prosthetic joint infection. Comparison of RA patients with a matched cohort of OA patients identified an increased risk of prosthetic joint infections (HR 4.08, 95% CI 1.35–12.33) in patients with RA.ConclusionPatients with RA who undergo total hip or knee replacement are at increased risk of prosthetic joint infection, which is further increased in the setting of revision arthroplasty and a previous prosthetic joint infection. These findings highlight the importance of perioperative prophylactic measures and vigilance during the postoperative period.
Risk of cardiovascular mortality in patients with rheumatoid arthritis: A meta‐analysis of observational studies
Authors: Aviña‐Zubieta J. Antonio , Choi Hyon K. , Sadatsafavi Mohsen , Etminan Mahyar , Esdaile John M. , Lacaille Diane 
Published: November 2008

AbstractObjectiveTo determine the magnitude of risk of cardiovascular mortality in patients with rheumatoid arthritis (RA) compared with the general population through a meta‐analysis of observational studies.MethodsWe searched Medline, EMBase, and Lilacs databases from their inception to July 2005. Observational studies that met the following criteria were assessed by 2 researchers: 1) prespecified RA definition, 2) clearly defined cardiovascular disease (CVD) outcome, including ischemic heart disease (IHD) and cerebrovascular accidents (CVAs), and 3) reported standardized mortality ratios (SMRs) and 95% confidence intervals (95% CIs). We calculated weighted–pooled summary estimates of SMRs (meta‐SMRs) for CVD, IHD, and CVAs using the random‐effects model, and tested for heterogeneity using the I2 statistic.ResultsTwenty‐four studies met the inclusion criteria, comprising 111,758 patients with 22,927 cardiovascular events. Overall, there was a 50% increased risk of CVD death in patients with RA (meta‐SMR 1.50, 95% CI 1.39–1.61). Mortality risks for IHD and CVA were increased by 59% and 52%, respectively (meta‐SMR 1.59, 95% CI 1.46–1.73 and meta‐SMR 1.52, 95% CI 1.40–1.67, respectively). We identified asymmetry in the funnel plot (Egger's test P = 0.002), as well as significant heterogeneity in all main analyses (P < 0.0001). Subgroup analyses showed that inception cohort studies (n = 4, comprising 2,175 RA cases) were the only group that did not show a significantly increased risk for CVD (meta‐SMR 1.19, 95% CI 0.86–1.68).ConclusionPublished data indicate that CVD mortality is increased by ∼50% in RA patients compared with the general population. However, we found that study characteristics may influence the estimate.
Short‐term improvement of endothelial function in rituximab‐treated rheumatoid arthritis patients refractory to tumor necrosis factor α blocker therapy
Authors: Gonzalez‐Juanatey Carlos , Llorca Javier , Vazquez‐Rodriguez Tomas R. , Diaz‐Varela Nicolas , Garcia‐Quiroga Hermitas , Gonzalez‐Gay Miguel A. 
Published: November 2008

AbstractObjectiveCardiovascular disease is the major cause of excessive mortality in rheumatoid arthritis (RA) and endothelial dysfunction plays a key role in atherosclerosis. The aim of the present study was to assess whether rituximab therapy was able to improve endothelial function in RA patients refractory to tumor necrosis factor α (TNFα) blockers.MethodsSix consecutive RA patients (5 women; age range 55–79 years) with active disease refractory to TNFα inhibitor therapy were studied. Patients received intravenous rituximab (1 course, consisting of 2 infusions of 1,000 mg each separated by 2 weeks). Flow‐mediated endothelium‐dependent vasodilatation (FMD%) and endothelium‐independent vasodilatation (postnitroglycerin) were measured at day 0 prior to the first rituximab infusion, at week 2 (before the second infusion), and at month 6.ResultsAt week 2, a dramatic increase in FMD% values was observed in all patients (mean ± SD 7.02 ± 2.31%, median 7.29%, range 3.2–9.75%) compared with those observed before the first infusion (mean ± SD 3.35 ± 1.58%, median 3.04%, range 1.69–5.89%). In addition, at month 6, FMD% values in all patients (mean ± SD 7.66 ± 1.73%, median 7.64%, range 5.61–9.98%) were greater than those found before the first infusion (P = 0.03). The dramatic improvement of FMD% was associated with a significant decrease in C‐reactive protein level and Disease Activity Score in 28 joints.ConclusionOur study demonstrates an active effect of rituximab on endothelial function in RA patients refractory to TNFα blockers.
Brain transport of neurotoxin‐I with PLA nanoparticles through intranasal administration in rats: a microdialysis study
Authors: Cheng Qiaoyuan , Feng Jian , Chen Jianming , Zhu Xuan , Li Fanzhu 
Published: November 2008

AbstractThe purpose of this study was to encapsulate neurotoxin‐I (NT‐I) within polylactic acid (PLA) nanoparticles (NPs) and to evaluate their transport into the brain after intranasal administration (i.n.) using a microdialysis sampling technique. NT‐I‐NPs (NT‐I radiolabeled with sodium [125I]iodide) were prepared and characterized. Then, NT‐I‐NPs were administered i.n. or i.v. to rats and the radioactivities in the olfactory bulbs were monitored for up to 240 min. The nanoparticles prepared were spherical with a homogenous size distribution. The mean particle size, zeta potential and entrapment efficiency were −28.6±2.3 mV, 65 nm and 35.5±2.8%, respectively. The brain transport results showed that the time to reach the peak level (Tmax) of NT‐I‐NPs (i.n.) was 65 min, shorter than NT‐I‐NPs (i.v.) (95 min) or NT‐I (i.v.) (145 min). The concentration at peak level (Cmax) and the total area under the concentration–time curves from zero to 4 h (AUC0–4 h) of each group followed the following order: NT‐I‐NPs (i.n.)>NT‐I‐NPs (i.v.)>NT‐I (i.v.). The corresponding absolute bioavailabilities (Fabs) of NT‐I‐NPs (i.n.) were about 160%, 196% with NT‐I‐NPs (i.v.) and NT‐I (i.v.) as reference preparations, respectively. The brain delivery of NT‐I could be enhanced with PLA nanoparticles either through i.n. or i.v. administration. Furthermore, the enhancement was more significant for i.n. than for i.v. administration. Nanoparticles as carriers would be a potential way to improve the brain transport for centrally active peptides. Copyright © 2008 John Wiley & Sons, Ltd.
The Biochemistry of Drug Metabolism – An Introduction
Authors: Testa Bernard , Krämer Stefanie D. 
Published: November 2008

AbstractThis review continues a general presentation of the metabolism of drugs and other xenobiotics begun in three recent issues ofChemistry & Biodiversity.The presentPartis dedicated to reactions of conjugation, namely methylation, sulfonation, and phosphorylation, glucuronidation and other glycosidations, acetylation and other acylations, the formation and fate of coenzyme A conjugates, glutathione conjugation, and the reaction of amines with carbonyl compounds. It presents the many transferases involved, their nomenclature, relevant biochemical properties, catalytic mechanisms, and the reactions they catalyze. Nonenzymatic reactions, mainly of glutathione conjugation, also receive due attention. A number of medicinally, environmentally, and toxicologically relevant examples are presented and discussed.
Tetrathiafulvalene Porphyrins
Authors: Nielsen Kent A. , Levillain Eric , Lynch Vincent M. , Sessler Jonathan L. , Jeppesen Jan O. 
Published: November 2008

AbstractFour tetrathiafulvalene (TTF)‐annulated porphyrins 1–4 were synthesized and characterized. All contain a tetraphenylporphyrin (TPP) core onto which four, two, or one TTF subunits were annulated. Absorption and fluorescence spectroscopic studies together with electrochemical investigations reveal that interactions between the porphyrin system and the annulated TTF units take place in solution. The annulation of one or more TTF units to the porphyrin core has a profound effect on the reduction potentials associated with this latter framework, with positive shifts in the range of 0.105 to 0.355 V and 0.200 to 0.370 V for the first and second reduction potential, respectively, compared to the corresponding processes in the model compound TPP, 18. The redox potentials for the first oxidation of the TTF units are considerably shifted in 4 (ΔEox1=+0.285 V) and 2 (ΔEox1=−0.140 V), whereas for 1 and 3 these potentials remain within the region expected for a normal TTF unit. Considerable changes in the second oxidation potential associated with the TTF subunits were seen for 2 (ΔEox1=−0.085) and 3 (ΔEox1=−0.175). The emission spectra of 1–4 revealed that the porphyrin fluorescence is almost quenched in the neutral state of the TTF‐annulated porphyrins, a finding that is consistent with substantial electron transfer taking place from the TTF subunits to the porphyrin core. Oxidation of the TTF unit(s) (TTF→TTF.+) present in 1–4 leads to the emission intensity being restored.
Which Properties of a Spanning Network of Hydration Water Enable Biological Functions?
Authors: Brovchenko Ivan , Oleinikova Alla 
Published: November 2008

AbstractThe central role of water in biological functions is well‐recognized, but numerous questions concerning the physical mechanisms behind the importance of water for life remain unanswered. Water in biosystems exists mainly as hydration water. Analysis of the phase diagram of hydration water shows that biological functions are possible only when the surfaces of biomolecules are covered by spanning hydrogen‐bonded networks of hydration water. The comparative studies of the various properties of hydrated biosystems in the presence and in the absence of a spanning water network should clarify its specific physical properties, which are crucial for biological functions. Herein, we summarize the recent progress in these studies. The biological activity of the living organisms is maximal in a narrow temperature interval, where the spanning network of hydration water breaks up with heating via a percolation transition. The entropy of the hydration water related to the diversity of cluster size diverges at this percolation threshold. The possible role of this phenomenon in life processes is discussed.
Relating streamflow characteristics to specialized insectivores in the Tennessee River Valley: a regional approach
Authors: Knight Rodney R. , Brian Gregory M. , Wales Amy K. 
Published: November 2008

AbstractAnalysis of hydrologic time series and fish community data across the Tennessee River Valley identified three hydrologic metrics essential to habitat suitability and food availability for insectivorous fish communities in streams of the Tennessee River Valley: constancy (flow stability or temporal invariance), frequency of moderate flooding (frequency of habitat disturbance), and rate of streamflow recession. Initial datasets included 1100 fish community sites and 300 streamgages. Reduction of these datasets to sites with coexisting data yielded 33 sites with streamflow and fish community data for analysis. Identification of critical hydrologic metrics was completed using a multivariate correlation procedure that maximizes the rank correlation between the hydrologic metrics and fish community resemblance matrices. Quantile regression was used to define thresholds of potential ranges of insectivore scores for given values of the hydrologic metrics. Increased values of constancy and insectivore scores were positively correlated. Constancy of streamflow maintains wetted perimeter, which is important for providing habitat for fish spawning and increased surface area for invertebrate colonization and reproduction. Site scores for insectivorous fish increased as the frequency of moderate flooding (3 times the median annual streamflow) decreased, suggesting that insectivorous fish communities respond positively to less frequent disturbance and a more stable habitat. Increased streamflow recession rates were associated with decreased insectivore scores. Increased streamflow recession can strand fish in pools and other areas that are disconnected from flowing water and remove invertebrates as food sources that were suspended during high‐streamflow events. Copyright © 2008 John Wiley & Sons, Ltd.
A dam problem: simulated upstream impacts for a Searsville‐like watershed
Authors: Heppner Christopher S. , Loague Keith 
Published: November 2008

AbstractThe integrated hydrology model (InHM), a physics‐based hydrologic‐response model with sediment‐transport capabilities, was used to simulate upstream impacts from dam construction/removal for a generalized approximation of the Searsville watershed in Portola Valley, California. Four 10‐year simulation scenarios (pre‐dam, early dam, current and post‐dam) were considered. Each scenario was simulated using the same sequence of synthetically generated rainfall and evapotranspiration. For each scenario the boundary‐value problem was constructed based on the available watershed information (e.g. topography, soils, geology, reservoir bathymetry and land use). The results from the simulations are presented in terms of the temporal and spatial characteristics of hydrologic response and sediment transport. The commonalities/differences between the four Searsville‐like watershed scenarios are discussed. The effort demonstrates that heuristic physics‐based simulation can be a useful tool for the characterization of dam‐related impacts at the watershed scale. Copyright © 2008 John Wiley & Sons, Ltd.
Rapid determination of sterols in vegetable oils by CEC using methacrylate ester‐based monolithic columns
Authors: Lerma‐García María Jesús , Simó‐Alfonso Ernesto F. , Ramis‐Ramos Guillermo , Herrero‐Martínez José M. 
Published: November 2008

AbstractA method for the determination of sterols in vegetable oils by CEC with UV–Vis detection, using methacrylate ester‐based monolithic columns, has been developed. To prepare the columns, polymerization mixtures containing monomers of different hydrophobicities were tried. The influence of composition of polymerization mixture was optimized in terms of porogenic solvent, monomers/porogens and monomer/crosslinker ratios. The composition of the mobile phase was also studied. The optimum monolith was obtained with lauryl methacrylate monomer at 60:40% (wt:wt) lauryl methacrylate/ethylene dimethacrylate ratio and 60 wt% porogens with 20 wt% of 1,4‐butanediol (12 wt% 1,4‐butanediol in the polymerization mixture). Excellent resolution between sterols was achieved in less than 7 min with an 85:10:5 v/v/v ACN–2‐propanol–water buffer containing 5 mM Tris at pH 8.0. The limits of detection were lower than 0.04 mM, and inter‐day and column‐to‐column reproducibilities at 0.75 mM were better than 6.2%. The method was applied to the determination of sterols in vegetable oils with different botanical origins and to detect olive oil adulteration with sunflower and soybean oils.
Composite high resolution localized relaxation scheme based on upwinding for hyperbolic conservation laws
Authors: Dubey Ritesh Kumar , Kadalbajoo M. K. 
Published: November 2008

AbstractIn this work we present an upwind‐based high resolution scheme using flux limiters. Based on the direction of flow we choose the smoothness parameter in such a way that it leads to a truly upwind scheme without losing total variation diminishing (TVD) property for hyperbolic linear systems where characteristic values can be of either sign. Here we present and justify the choice of smoothness parameters. The numerical flux function of a high resolution scheme is constructed using wave speed splitting so that it results into a scheme that truly respects the physical hyperbolicity property. Bounds are given for limiter functions to satisfy TVD property. The proposed scheme is extended for non‐linear problems by using the framework of relaxation system that converts a non‐linear conservation law into a system of linear convection equations with a non‐linear source term. The characteristic speed of relaxation system is chosen locally on three point stencil of grid. This obtained relaxation system is solved using composite scheme technique, i.e. using a combination of proposed scheme with the conservative non‐standard finite difference scheme. Presented numerical results show higher resolution near discontinuity without introducing spurious oscillations. Copyright © 2008 John Wiley & Sons, Ltd.
Triterpenoids from Eucalyptus camaldulensisDehnh. Tissue Cultures
Authors: Tsiri Dimitroula , Aligiannis Nektarios , Graikou Konstantia , Spyropoulos Caroline , Chinou Ioanna 
Published: November 2008

AbstractA chemical study on tissue cultures from leaves and flowers of E. camaldulensis Dehnh. afforded the new natural product (2α,3β)‐2,3,23‐trihydroxy‐13,28‐epoxyurs‐11‐en‐28‐one (dryobalanolide) together with the known pentacyclic triterpenoids: betulinic acid, oleanolic acid, ursolic acid, (2α,3β)‐2,3,23‐trihydroxyolean‐12‐en‐28‐oic acid (arjunolic acid), (2α,3β)‐2,3,23‐trihydroxyurs‐12‐en‐28‐oic acid (asiatic acid), (2α)‐2‐hydroxyursolic acid, (2α)‐2‐hydroxyoleanolic acid (maslinic acid), as well as β‐sitosterol. The extracts and the isolated compounds were evaluated against eleven human pathogenic microorganisms, exhibiting a very interesting antibacterial spectrum of activities.
Indole Alkaloids from the Leaves of Anthocephalus chinensis
Authors: Zhou Hua , He Hong‐Ping , Kong Ning‐Chuan , Wang Tie‐Jun , Hao Xiao‐Jiang 
Published: November 2008

AbstractAnthocephalusine A (1) and 3β‐isodihydrocadambine 4‐oxide (2) were isolated from the leaves of Anthocephalus chinensis (Rubiaceae), together with five known compounds. The structures were established by spectroscopic methods including 2D‐NMR analyses.
Oligonucleotide Analogues with Integrated Bases and Backbones. Part 19.
Authors: Bogliotti Nicolas , Ritter Anne , Hebbe Séverine , Vasella Andrea 
Published: November 2008

AbstractThe A*[s]U(*) dinucleosides 1 and 2 form thermoreversible gels in organic solvents. The basis of the gelation is the formation of linear aggregates by base pairing following desolvation of the nucleobases. This is evidenced by the absence of gel formation by the C(6)‐deaminated analogue 3 of 1, the correlation of gelation with the anti‐conformation, as preferred for 1, and the temperature‐, concentration‐, and time‐dependent CD spectra. The gels were also characterized by the minimum gelation concentration, the gel–sol transition (melting) temperature, and rheological properties.
MiRNA expression in urothelial carcinomas: Important roles of miR‐10a, miR‐222, miR‐125b, miR‐7 and miR‐452 for tumor stage and metastasis, and frequent homozygous losses of miR‐31
Authors: Veerla Srinivas , Lindgren David , Kvist Anders , Frigyesi Attila , Staaf Johan , Persson Helena , Liedberg Fredrik , Chebil Gunilla , Gudjonsson Sigurdur , Borg Åke , Månsson Wiking , Rovira Carlos , Höglund Mattias 
Published: November 2008

AbstractWe analyzed 34 cases of urothelial carcinomas by miRNA, mRNA and genomic profiling. Unsupervised hierarchical clustering using expression information for 300 miRNAs produced 3 major clusters of tumors corresponding to Ta, T1 and T2‐T3 tumors, respectively. A subsequent SAM analysis identified 51 miRNAs that discriminated the 3 pathological subtypes. A score based on the expression levels of the 51 miRNAs, identified muscle invasive tumors with high precision and sensitivity. MiRNAs showing high expression in muscle invasive tumors included miR‐222 and miR‐125b and in Ta tumors miR‐10a. A miRNA signature for FGFR3 mutated cases was also identified with miR‐7 as an important member. MiR‐31, located in 9p21, was found to be homozygously deleted in 3 cases and miR‐452 and miR‐452* were shown to be over expressed in node positive tumors. In addition, these latter miRNAs were shown to be excellent prognostic markers for death by disease as outcome. The presented data shows that pathological subtypes of urothelial carcinoma show distinct miRNA gene expression signatures. © 2008 Wiley‐Liss, Inc.