bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular Editing and Assessment of the Cytotoxic Properties of Iejimalide and Progeny
Authors: Gagnepain Julien , Moulin Emilie , Nevado Cristina , Waser Mario , Maier Armin , Kelter Gerhard , Fiebig Heinz‐Herbert , Fürstner Alois 
Published: May 2011

AbstractSystematic variation of all substructures embedded into the framework of iejimalide B (2) led to a panel of synthetic analogues of this polyunsaturated macrolide, featuring structural modifications that are not accessible by derivatization of the natural lead compound itself. The assessment of the cytotoxicity of these compounds with the aid of a monolayer proliferation assay (12 human tumor cell lines in vitro) as well as a colony formation assay (24 human tumor xenografts ex vivo) revealed the exceptional potency of 2 and several of its synthetic congeners, with IC50 values in the picomolar range for the most sensitive cell lines. Whereas structural modifications of the macrocycle or of the side chain generally lead to a decrease in activity, changes of the peptidic terminus are not only well accommodated but engender increased tumor selectivity as well. 2 and two of the most promising analogues were selected for in vivo studies in mice, in which their activity against human tumor xenografts of breast cancer (MAXF 401) and prostate cancer (PRXF PC‐3M) was tested. In contrast to a previous report in the literature however, which had claimed in vivo activity for the parent iejimalides, these tests did not show a significant therapeutic effect against the chosen solid tumors upon intraperitoneal administration.
Pd‐Catalyzed [2+2+1] Coupling of Alkynes and Arenes: Phenol Diazonium Salts as Mechanistic Trapdoors
Authors: Schmidt Bernd , Berger René , Kelling Alexandra , Schilde Uwe 
Published: May 2011

AbstractAlkynes and phenol diazonium salts undergo a Pd‐catalyzed [2+2+1] cyclization reaction to spiro[4,5]decatetraene‐7‐ones. This structure was confirmed for one example by X‐ray single‐crystal structure analysis. The reaction is believed to proceed through oxidative addition of the phenol diazonium cation to Pd0, subsequent insertion of two alkynes, followed by irreversible spirocyclization.
Nanometer‐Sized Reactor—A Porphyrin‐Based Model System for Anion Species
Authors: Li Yong‐jun , Zhao Ying‐jie , Flood Amar H. , Liu Chao , Liu Hui‐biao , Li Yu‐liang 
Published: May 2011

AbstractAlthough many cagelike molecules can create a catalytic environment for promoting chemical reactions, the construction of receptors that can host anionic species and sensitize their reaction is novel. Here we report the photochemically induced dimerization of the anion radicals of TCNQ (7,7,8,8‐tetracyano‐para‐quinodimethane) in organic solvent under aerobic conditions when they are encapsulated inside a cationic photoactive receptor. There is clear evidence for a rate increase of over two orders of magnitude, photosensitization of the host, and demonstrated turnover of the catalyst.
Hydrolysis of a Basic Bismuth Nitrate—Formation and Stability of Novel Bismuth Oxido Clusters
Authors: Miersch Linda , Schlesinger Maik , Troff Ralf W. , Schalley Christoph A. , Rüffer Tobias , Lang Heinrich , Zahn Dirk , Mehring Michael 
Published: May 2011

AbstractThe synthesis of the nanoscaled bismuth oxido clusters [Bi38O45‐ (NO3)20(DMSO)28](NO3)4⋅4 DMSO (1 a) and [Bi38O45(OH)2(pTsO)8‐ (NO3)12(DMSO)24](NO3)2⋅4 DMSO⋅ 2 H2O (2) starting from the basic bismuth nitrate [Bi6O4(OH)4](NO3)6⋅H2O is reported herein. Single‐crystal X‐ray diffraction analysis, ESI mass spectrometry, thermogravimetric analysis, and molecular dynamics simulation were used to study the formation, structure, and stability of these large metal oxido clusters. Compounds 1 a and 2 are based on a [Bi38O45]24+ core, which is structurally related to δ‐Bi2O3. Examination of the fragmentation pathways of 1 a and 2 by infrared multi‐photon dissociation (IRMPD) tandem MS experiments allows the identification of novel bismuth oxido cluster species in the gas phase.
Correlation Between HLA‐DRB1, HLA‐DQB1 Polymorphism and Autoantibodies Against Angiotensin AT1 Receptors in Chinese Patients With Essential Hypertension
Authors: Zhu Feng , Sun Yanxiang , Wang Min , Ma Shihui , Chen Xiao , Cao Ailin , Chen Fen , Qiu Yan , Liao Yuhua 
Published: May 2011

AbstractBackground:The autoantibodies (AAs) against angiotensin AT1 receptors (AT1‐AAs) have been discovered in patients with preeclampsia, malignant hypertension, and essential hypertension (EH); however, the mechanism of AA production remains to be investigated.Hypothesis:Polymorphisms of HLA‐DRB1 or HLA‐DQB1 are related to production of AAs in autoimmune diseases. We hypothesis that the polymorphisms of the HLA molecules are also associated with production of AT1‐AAs in patients with EH.Methods:We enrolled 394 patients with EH and 224 normotensive subjects in this study. Autoantibodies in sera of donors were detected by enzyme‐linked immunosorbent assay. The subjects' clinical data were collected, including gender, age, body mass index, blood pressure, smoking status, and diabetes. The patients and the normotensive subjects were classified respectively into AA‐positive and AA‐negative groups. Typing of DNA for HLA‐DRB1 and HLA‐DQB1 alleles was done by polymerase chain reaction amplification with sequence‐specific primers.Results:Thirteen HLA‐DRB1 and 7 HLA‐DQB1 alleles were found in this population. The frequencies of AT1‐AAs were related to blood pressure level. The frequency of AT1‐AAs in the EH group was higher than that in the normotensive group (P = 0.0001). The levels of AAs in different groups of EH show a significant difference (P = 0.027). In addition, HLA‐DRB1*04 and HLA‐DRB1*14 (odds ratio [OR]: 3.06, 95% confidence interval [CI]: 1.56–5.97, P = 0.001; and OR: 2.53, 95% CI: 1.080–5.91, P = 0.033, respectively) were related to AT1‐AA production in normotensive subjects after adjusting for covariants. The HLA‐DRB1*04 allele might be related to AT1‐AA production in hypertensive subjects, and the P value was of baseline statistical significance after adjusting for blood pressure and other covariants (OR: 1.63, 95% CI: 0.95–2.78, P = 0.070).Conclusions:These results suggest a difference in the immunogenetic background between the positive and negative AAs with hypertension or normotension. The HLA‐DRB1*04 allele increases the risk for AT1‐AA production. © 2011 Wiley Periodicals, Inc.The first two authors contributed equally to this work.This study was supported by a grant from the National Natural Science Foundation of China (No. 03600235). The authors have no other funding, financial relationships, or conflicts of interest to disclose.
Gender‐Related Differences in Patients With ST‐Elevation Myocardial Infarction: Results From the Registry Study of the ST Elevation Myocardial Infarction Network Essen
Authors: Hailer Birgit , Naber Christoph , Koslowski Bernd , van Leeuwen Peter , Schäfer Harald , Budde Thomas , Jacksch Rainer , Sabin Georg , Erbel Raimund ,   for the Myocardial Infarction Network Essen
Published: May 2011

AbstractBackground:The Myocardial Infarction Network Essen was initiated in order to establish a standardized procedure with immediate reopening of the infarcted vessel for patients with ST‐elevation myocardial infarction (STEMI) in the city of Essen, Germany. The present study aims to evaluate gender‐related differences in presentation of disease and clinical outcome.Hypothesis:Gender is associated with differences in presentation and outcome of STEMI.Methods:All patients with STEMI were included without exception. Parameters such as risk profile, mortality, and relevant time intervals were documented. The follow‐up period was 1 year.Results:For this study, 1365 patients (72.1% male) were recruited. Women were significantly older, with higher prevalence of diabetes (28.1% vs 20.3%, P = 0.004) and hypertension (76.5% vs 64.8%, P<0.0005). Analysis of time intervals between symptoms to actions showed no significant differences. However, women tended to wait longer before calling for medical assistance (358 vs 331 min, P = 0.091). In‐hospital mortality was comparable with respect to gender, whereas women had higher 1‐year mortality (18.6% vs 13.2%). Age and diabetes were associated with a higher mortality. Adjusted for age, gender is no longer an independent risk factor. In the follow‐up period, significantly more women were readmitted to the hospital without a difference in the frequency of reangiography, surgery, or target‐vessel revascularization.Conclusions:The present data display a successful implementation of a standardized procedure in patients with STEMI. Although differences between genders are not as obvious as expected, efforts should be taken to perform a gender‐specific risk analysis as well as to promote education about proper behavior in case of new onset of angina. © 2011 Wiley Periodicals, Inc.The authors have no funding, financial relationships, or conflicts of interest to disclose.
The Approach of Conformational Chimeras to Model the Role of Proline‐Containing Helices on GPCR Mobility: the Fertile Case of Cys‐LTR1
Authors: Bettinelli Ilaria , Graziani Davide , Marconi Cristina , Pedretti Alessandro , Vistoli Giulio 
Published: May 2011

AbstractThe homology modeling of GPCRs has benefitted vastly from the availability of some resolved structures, which allow the generation of many reliable GPCR models. However, the dynamic behavior of such receptors has been only minimally examined in silico, although several pieces of evidence have highlighted some conformational switches that can orchestrate the activation mechanism. Among such switches, Pro‐containing helices play a key role in determining bending in TM helices and thereby the width of the TM bundle. The approach proposed herein involves the generation of a set of possible models (conformational chimeras) by exhaustively combining the two main conformations (straight and bent) that a Pro‐containing helix can assume. This approach was validated by generating conformational chimeras for the Cys‐LTR1 receptor, which is involved in contractile and inflammatory processes. The generated chimeras were then used for docking a small set of representative ligands. The results revealed the flexibility mechanisms of Cys‐LTR1, showing how the docked agonists vary their stabilizing interactions, shifting from the open to closed state, and how the examined antagonists are able to block the receptor in an open and inactive conformation, thus behaving as inverse agonists. This study emphasizes the promising potential of chimera modeling, confirms the key role of proline residues in receptor activation, and suggests that docking results can be improved by considering the often‐overlooked flexibility of receptors.
Discovery of a Competitive Apelin Receptor (APJ) Antagonist
Authors: Macaluso N. J. Maximilian , Pitkin Sarah L. , Maguire Janet J. , Davenport Anthony P. , Glen Robert C. 
Published: May 2011

AbstractThe apelin receptor (APJ) is a class A G‐protein‐coupled receptor (GPCR) and is a putative target for the treatment of cardiovascular and metabolic diseases. Apelin‐13 (NH2‐QRPRLSHKGPMPF‐COOH) is a vasoactive peptide and one of the most potent endogenous inotropic agents identified to date. We report the design and discovery of a novel APJ antagonist. By using a bivalent ligand approach, we have designed compounds with two ′affinity′ motifs and a short series of linker groups with different conformational and non‐bonded interaction properties. One of these, cyclo(1–6)CRPRLC‐KH‐cyclo(9–14)CRPRLC is a competitive antagonist at APJ. Radioligand binding in CHO cells transfected with human APJ gave a Ki value of 82 nM, competition binding in human left ventricle gave a KD value of 3.2 μM, and cAMP accumulation assays in CHO‐K1‐APJ cells gave a KD value of 1.32 μM.
Cytopathology of “double‐hit” non‐Hodgkin lymphoma
Authors: Elkins Camille T. , Wakely Paul E. 
Published: May 2011

AbstractBACKGROUND:B‐cell lymphomas with concurrent IGH‐BCL2 and c‐MYC rearrangements (so‐called “double‐hit lymphomas” [DHL]) are a relatively rare, recently described category in the 2008 World Health Organization classification of hematopoietic neoplasms. Response to chemotherapy and survival are poor.METHODS:The authors reviewed files of cytogenetically documented DHL to identify cytologic features that would allow its possible recognition.RESULTS:Twelve fine‐needle aspirates (FNAs), 2 pleural fluids, and 1 touch imprint of cytogenetically proven DHL were uncovered. Primary DHL was correctly recognized in 3 of 12 FNA cases using Ki‐67 staining coupled with a positive bcl‐2 result as the basis for performing fluorescence in situ hybridization (FISH) analysis of c‐MYC and IGH‐BCL2 rearrangements. Remaining FNAs and non‐FNA cases were diagnosed as non‐Hodgkin lymphoma, B‐cell lymphoma, or atypical lymphocytosis. Ten cases had cell block material available. All cases had high cellularity with a dissociated smear pattern and background lymphoglandular bodies. Cell size ranged from intermediate to large. Nuclei were predominantly rounded or slightly irregular in contour; 4 FNAs had markedly cleaved nuclei. Some nuclei harbored discrete but small nucleoli, whereas in others coarse chromatin and indistinct or multiple small nucleoli existed. A variable number of mitotic figures, tingible body macrophages, and background apoptotic cells were also present.CONCLUSIONS:No specific cytomorphologic feature(s) were found to reliably identify DHL using FNA or exfoliative cytology. A high Ki‐67 proliferation index and positive bcl‐2 staining (on cytospin slides or cell block material) of cases not conforming to typical Burkitt lymphoma morphology should prompt FISH analysis for c‐MYC and/or IGH‐BCL2 rearrangements to identify DHL, particularly if tissue biopsy is not expected. Cancer (Cancer Cytopathol) 2011;. © 2011 American Cancer Society
Dancing on DNA: Kinetic Aspects of Search Processes on DNA
Authors: Tafvizi Anahita , Mirny Leonid A. , van Oijen Antoine M. 
Published: May 2011

AbstractRecognition and binding of specific sites on DNA by proteins is central for many cellular functions such as transcription, replication, and recombination. In the search for its target site, the DNA‐associated protein is facing both thermodynamic and kinetic difficulties. The thermodynamic challenge lies in recognizing and tightly binding a cognate (specific) site among the billions of other (non‐specific) sequences on the DNA. The kinetic difficulty lies in finding a cognate site in mere seconds amidst the crowded cellular environment that is filled with other DNA sequences and proteins. Herein, we discuss the history of the DNA search problem, the theoretical background and the various experimental methods used to study the kinetics of proteins searching for target sites on DNA.
Composition and morphology control of Fex(PO4)y(OH)z·nH2O microcrystals
Authors: Ming Hai , Yu Hang , Wei Huaixin , Liu Yang , Li Haitao , He Xiaodie , Huang Hui , Kang Zhenhui 
Published: May 2011

AbstractA series of Fex(PO4)y(OH)z·nH2O microcrystals were prepared by the hydrothermal reaction at 150 °C. The ratio of Fe2+/Fe3+ in Fex(PO4)y(OH)z·nH2O microcrystals can be adjusted by using Na2S2O3·5H2O as a reducing agent. The morphology control of Fex(PO4)y(OH)z·nH2O microcrystals was realized through regulating the molar ratio of LiAc·2H2O/FeCl3. Further, the morphology, structure and composition of Fex(PO4)y(OH)z·nH2O microcrystals were also investigated by x‐ray diffraction (XRD), x‐ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) techniques. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis of Biobased Succinonitrile from Glutamic Acid and Glutamine
Authors: Lammens Tijs M. , Le Nôtre Jérôme , Franssen Maurice C. R. , Scott Elinor L. , Sanders Johan P. M. 
Published: May 2011

AbstractSuccinonitrile is the precursor of 1,4‐diaminobutane, which is used for the industrial production of polyamides. This paper describes the synthesis of biobased succinonitrile from glutamic acid and glutamine, amino acids that are abundantly present in many plant proteins. Synthesis of the intermediate 3‐cyanopropanoic amide was achieved from glutamic acid 5‐methyl ester in an 86 mol % yield and from glutamine in a 56 mol % yield. 3‐Cyanopropanoic acid can be converted into succinonitrile, with a selectivity close to 100 % and a 62 % conversion, by making use of a palladium(II)‐catalyzed equilibrium reaction with acetonitrile. Thus, a new route to produce biobased 1,4‐diaminobutane has been discovered.
Peak‐to‐average power ratio reduction and digital predistortion effects in power amplifiers in OFDM system
Authors: Varahram Pooria , Ali Borhanuddin Mohd 
Published: May 2011

SUMMARYIn this paper, the effects of peak‐to‐average power ratio reduction in nonlinear power amplifiers (PAs) by considering memory effects and of digital predistortion are investigated. A new predistortion technique is proposed, which is called the complex gain memory predistortion (CGMP) method. The CGMP is applied to compensate the dynamic memory effects of PAs. The conventional partial transmit sequence method is applied for peak‐to‐average power ratio reduction, and combining it with the CGMP results in efficiency enhancement and spectrum efficiency improvement. Simulation and results are examined with the two types of PAs and with an OFDM signal with quadrature phase‐shift keying modulation. Copyright © 2011 John Wiley & Sons, Ltd.
Marital functioning and binge eating disorder in married women
Authors: Whisman Mark A. , Dementyeva Anastasia , Baucom Donald H. , Bulik Cynthia M. 
Published: May 2011

AbstractObjective:The purpose of this study was to evaluate the association between marital functioning and binge eating disorder (BED).Method:In a population‐based survey of 2,084 married women, women with current (i.e., occurring in the past 12 months) BED were compared on three measures of marital functioning (marital satisfaction, negative interaction, and positive interaction) to women with (a) other current Axis I disorders and (b) no current disorder.Results:Women with BED reported lower levels of marital satisfaction and higher levels of negative interaction than women with other disorders, who in turn reported poorer functioning than women with no disorder. Women with other disorders reported lower levels of positive interaction than women with BED, who in turn reported lower levels than women with no disorder.Discussion:Findings suggest that marital functioning for women with BED is comparable to or worse than for women with other psychiatric disorders, which supports the need for continued investigation into the marital functioning of people with BED. © 2011 by Wiley Periodicals, Inc. (Int J Eat Disord 2012;)
The predictive validity of the DEBQ‐external eating scale for eating in response to food commercials while watching television
Authors: van Strien Tatjana , Peter Herman C. , Anschutz Doeschka 
Published: May 2011

AbstractObjective:To challenge the conclusion by Jansen et al., Int J Eat Disord 2011; 44:164–168, that the widely used Dutch Eating Behavior Questionnaire (DEBQ) External Eating subscale (DEBQ‐EX) lacks validity for external eating, because of limitations of that study.Method:In a seminaturalistic setting we measured participants' intake of crisps and M&Ms while they watched food commercials or neutral commercials spliced into a film. To avoid misclassification due to the use of median splits we used extreme scores on the DEBQ‐ex (n = 60) in addition to the full range of scores (n = 125).Results:As was expected, high external eaters in the food commercial condition ate more crisps than did high external eaters in the neutral commercial condition, whereas low external eaters did not eat more crisps in one condition than in the other. No such moderator effect was found for emotional eating. No significant moderator effect was found for external eating in the original sample (n = 125) using the median‐split procedure.Discussion:The DEBQ scale for external eating has validity and specificity for external eating provided that the participants have sufficiently extreme external eating scores and a natural setting is used. © 2011 by Wiley Periodicals, Inc. (Int J Eat Disord 2012)
Antiferromagnetic Co–Gd Interactions in a Tetranuclear [CoGd]2 Complex with Low‐Spin Square‐Planar Co Ions – Role of the Singly Occupied 3d Co Magnetic Orbital
Authors: Gómez Verónica , Vendier Laure , Corbella Montserrat , Costes Jean‐Pierre 
Published: May 2011

AbstractA trianionic ligand H3L [2‐hydroxy‐N‐(2‐{[(2‐hydroxyphenyl)methylene]amino}‐2‐methylpropyl)benzamide] with an inner N2O2 coordination site and an oxygen atom coming from an amide function not involved in this site yields a monoanionic LCo‐pipH+ complex, in which the CoII ion is in a square‐planar environment and a low‐spin state S = 1/2. Further reaction with GdCl3·6H2O and tetramethylheptanedione (Hthd) yields a dinuclear Co–Gd complex that self‐assembles into a tetranuclear species, as demonstrated by the structural determination of the [LCoGd(thd)2(MeOH)]2 complex. This genuine entity is the first example in which a CoII ion in a low‐spin state is associated with a gadolinium ion. The magnetic studies confirm that two antiferromagnetic interactions are active through the double phenoxo bridge (J = –1.0 cm–1) and through the single amide bridge (j = –0.1 cm–1). Contrary to the large majority of 3d–Gd complexes that present ferromagnetic interactions, the involvement of a dxy or dyz cobalt orbital is responsible for the presence of an antiferromagnetic interaction.
The Al50Cp*12 Cluster – A 138‐Electron Closed Shell (L = 6) Superatom
Authors: Clayborne Peneé A. , Lopez‐Acevedo Olga , Whetten Robert L. , Grönbeck Henrik , Häkkinen Hannu 
Published: May 2011

AbstractMetal clusters stabilized by a surface ligand shell represent an interesting intermediate state of matter between molecular metal–ligand complexes and bulk metal. Such “metalloid” clusters are characterized by the balance between metal–metal bonds in the core and metal–ligand bonds at the exterior of the cluster. In previous studies, the electronic stability for the Al50Cp*12 cluster was not fully understood. We show here that the known cluster Al50Cp*12 can be considered as an analogue to a giant atom (“superatom”) with 138 sp electrons organized in concentric angular momentum shells up to L = 6 symmetry.
Simple Electrodeposition of Dendritic Au Rods from Sulfite‐Based Au(I) Electrolytes with High Electrocatalytic and SERS Activities
Authors: Hyun Myeounghee , Choi Suhee , Lee Young Wook , Kwon Soo Han , Han Sang Woo , Kim Jongwon 
Published: May 2011

AbstractFabrication of dendritic Au rod (DAR) structures on Au surfaces via a simple electrodeposition from sulfite‐based electrolytes containing Au(I) has been demonstrated. Scanning electron microscopic images show that the DAR structures contain highly faceted star‐shaped protrusions in sub‐100 nm scale. Electrochemical and X‐ray diffraction results reveal that the DAR structures retain high amount of (110) and (100) crystalline domains on their surfaces. The unique morphology and surface orientation of DAR provide high electrocatalytic activities for glucose oxidation and oxygen reduction and efficient surface‐enhanced Raman scattering activities.