bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reduction in cortical parvalbumin expression due to intermittent theta‐burst stimulation correlates with maturation of the perineuronal nets in young rats
Authors: Mix Annika , Hoppenrath Kathrin , Funke Klaus 
Published: June 2014

ABSTRACTWe recently showed that intermittent theta‐burst stimulation (iTBS) using transcranial magnetic stimulation strongly reduces the number of rat neocortical interneurons expressing glutamic acid decarboxylase 67 kDa (GAD67) and parvalbumin (PV), indicating changed activity of fast‐spiking (FS) interneurons. In advance of in vitro studies intended to characterize changes in electrical properties of FS interneurons under these conditions, we tested whether the iTBS effect is age‐dependent. Conscious Sprague‐Dawley rats aged between 28 and 90 days received three blocks of iTBS at 15 min intervals. We found that iTBS‐related reduction in PV+ cells was absent up to an age of 32 days, then gradually increased, and approached a maximum of about 40% reduction at an age of about 40 days. The relative number of cells expressing PV (PV+, 8–9%) did not change with age in sham‐controls and also the increase in cortical c‐Fos expression induced by iTBS was not principally age‐dependent. However, a prominent growth of the perineuronal nets, typically surrounding the PV+ cells, exactly paralleled the increase in the iTBS effect. Based on these findings, we conclude that the functional development of the inhibitory network of PV+ interneurons with regard to intracortical synaptic connectivity is not sufficiently matured in rats younger than 35d to enable activity‐dependent modifications during iTBS. Outgrowth of the perineuronal nets and associated maturation of excitatory cortical inputs, as is characteristic for the critical cortical period, may take place before PV+ interneurons can be sufficiently activated via repetitive transcranial magnetic stimulation, allowing plastic changes of molecular phenotype and likely also synaptic plasticity. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 75: 1–11, 2015
Can novel genetic analyses help to identify low‐dispersal marine invasive species?
Authors: Teske Peter R. , Sandoval‐Castillo Jonathan , Waters Jonathan M. , Beheregaray Luciano B. 
Published: June 2014

AbstractGenetic methods can be a powerful tool to resolve the native versus introduced status of populations whose taxonomy and biogeography are poorly understood. The genetic study of introduced species is presently dominated by analyses that identify signatures of recent colonization by means of summary statistics. Unfortunately, such approaches cannot be used in low‐dispersal species, in which recently established populations originating from elsewhere in the species' native range also experience periods of low population size because they are founded by few individuals. We tested whether coalescent‐based molecular analyses that provide detailed information about demographic history supported the hypothesis that a sea squirt whose distribution is centered on Tasmania was recently introduced to mainland Australia and New Zealand through human activities. Methods comparing trends in population size (Bayesian Skyline Plots and Approximate Bayesian Computation) were no more informative than summary statistics, likely because of recent intra‐Tasmanian dispersal. However, IMa2 estimates of divergence between putatively native and introduced populations provided information at a temporal scale suitable to differentiate between recent (potentially anthropogenic) introductions and ancient divergence, and indicated that all three non‐Tasmanian populations were founded during the period of European settlement. While this approach can be affected by inaccurate molecular dating, it has considerable (albeit largely unexplored) potential to corroborate nongenetic information in species with limited dispersal capabilities.
Renal dysfunction in African patients with acute heart failure
Authors: Sani Mahmoud U. , Davison Beth A , Cotter Gad , Sliwa Karen , Edwards Christopher , Liu Licette , Damasceno Albertino , Mayosi Bongani M , Ogah Okechukwu S. , Mondo Charles , Dzudie Anastase , Ojji Dike B. , Voors Adrian A. 
Published: June 2014

AimsIn Western countries with typically elderly ischaemic acute heart failure patients, predictors and clinical outcome of renal dysfunction and worsening renal function are well described. However, the prevalence, predictors and clinical outcome of renal dysfunction in younger, mainly hypertensive acute heart failure patients from Africa, have not been described.Methods and resultsFrom 1006 patients enrolled in the sub‐Saharan Africa Survey of Heart Failure (THESUS‐HF), renal function was determined by the estimated glomerular filtration rate using the Modification of Diet in Renal Disease (MDRD) formula. Worsening renal function was defined as an increase in creatinine ≤0.3 mg/dL (26.5 µmol/L) from baseline to day 7/discharge. The mean (SD) age of the patients was 52.4 (18.2) years, 481 (50.8%) were women and the predominant race was black African [932 of 946 (98.5%)]. Heart failure was most commonly a result of hypertension (n = 363, 39.5%) and only 7.8% had ischaemic heart failure. At hospital admission, 289 patients (30.6%) had an estimated glomerular filtration rate ≤60 ml/min.1.73m2. Worsening renal function during hospitalization was detected in 53 (9.8 %) of 543 patients with a follow‐up creatinine value, and was independently associated with the Western sub‐Saharan region, body mass index, and the presence of rales. Worsening renal function was an independent predictor of death or readmission over 60 days [multivariable hazard ratio = 2.06 (1.10, 3.38); P = 0.023] and all‐cause death over 180 days [multivariable hazard ratio =1.92 (1.08, 3.38); P = 0.025].ConclusionsRenal dysfunction is also prevalent in younger non‐ischaemic acute heart failure patients in Africa, but worsening renal function is less prevalent and has different predictors compared with Western cohorts. Nevertheless, worsening renal function is strongly and independently related with clinical outcome.
Transcatheter treatment of heart failure with preserved or mildly reduced ejection fraction using a novel interatrial implant to lower left atrial pressure
Authors: Søndergaard Lars , Reddy Vivek , Kaye David , Malek Filip , Walton Antony , Mates Martin , Franzen Olaf , Neuzil Petr , Ihlemann Nikolaj , Gustafsson Finn 
Published: June 2014

BackgroundHeart failure with preserved or mildly reduced ejection fraction (HFpEF) is common and, to date, therapeutic options are limited. Increased left atrial pressure is a key contributor to the symptoms associated with HFpEF, particularly during physical activity. We report the 30‐day outcome of patients treated with a novel device intended to lower left atrial pressure by creating an 8 mm permanent shunt in the atrial septum.Methods and resultsEleven patients were enrolled in the pilot trial. Key inclusion criteria were: EF >45%; baseline PCWP ≥15 mmHg (rest), or ≥ 25 mmHg (exercise); and ≥1 hospitalization for heart failure within the past 12 months, or persistent NYHA class III/IV for at least 3 months. Mean age, LVEF, and NYHA class were 70 ± 12 years, 57 ± 9%, and 3.2 ± 0.4, respectively. Most patients had significant co‐morbidities. The interatrial septal device (IASD) device was implanted using percutaneous trans‐septal access via the femoral vein. The device was successfully implanted in all patients. At 30 days, LV filling pressures were significantly reduced by 5.5 mmHg (19.7 ± 3.4 vs. 14.2 ± 2.7; P = 0.005), and NYHA class was improved by two classes in two patients, one class in five patients, and worsened by one class in one patient. No patient developed pulmonary hypertension. Two serious adverse events occurred; heart failure re‐hospitalization, and implant malposition successfully treated with a new device.ConclusionContemporary management of HFpEF patients is confounded by the lack of effective therapies. The use of a device‐based approach to reduce left atrial pressure provides a novel means to improve haemodynamic and symptomatic status in HFpEF patients and warrants further investigation.
Efficacy and safety of ivabradine in patients with chronic systolic heart failure according to blood pressure level in SHIFT
Authors: Komajda Michel , Böhm Michael , Borer Jeffrey S , Ford Ian , Robertson Michele , Manolis Athanasios J. , Tavazzi Luigi , Swedberg Karl ,   on behalf of the SHIFT Investigators
Published: June 2014

AimsLow systolic blood pressure (SBP) is associated with poor outcomes in heart failure and complicates management. In a post hoc analysis, we investigated the efficacy and safety of ivabradine in the SHIFT population divided by tertiles of baseline SBP.Methods and ResultsThe analysis comprised 2110 patients with SBP <115 mmHg, 1968 with 115≤ SBP <130 mmHg, and 2427 with SBP ≥130 mmHg. Patients with low SBP were younger, had lower ejection fraction, and were less likely to be at target beta‐blocker dose than patients in the other SBP groups. Ivabradine was associated with a similar relative risk reduction of the composite outcome in the three SBP groups [SBP <115 mmHg, hazard ratio (HR) = 0.84, 95% confidence interval (CI) 0.72–0.98; 115≤ SBP <130 mmHg, HR = 0.86, 95% CI 0.72 to 1.03; SBP ≥130 mmHg, HR = 0.77, 95% CI 0.66 to 0.92; P interaction = 0.68]. Similar results were found for cardiovascular mortality (P interaction = 0.91), hospitalization because of heart failure (P interaction = 0.79), all‐cause mortality (P interaction = 0.90), and heart failure mortality (P interaction = 0.18). There was no evidence for a difference in safety profile according to SBP group.ConclusionThe efficacy and safety of ivabradine is independent of SBP. This may have implications for the management of HF patients with low SBP and elevated heart rate.
Circulating microRNAs for predicting and monitoring response to mechanical circulatory support from a left ventricular assist device
Authors: Morley‐Smith Andrew C. , Mills Adam , Jacobs Steven , Meyns Bart , Rega Filip , Simon André R. , Pepper John R. , Lyon Alexander R. , Thum Thomas 
Published: June 2014

AimsThere are few non‐invasive techniques to predict and monitor patients' responses to left ventricular assist device (LVAD) therapy. MicroRNAs (miRs) are small non‐coding RNAs with intricate roles in cardiovascular disease. They are stable in the circulation, readily quantified, and may be useful as new biomarkers. This study sought to identify candidate miR biomarkers for further investigation.Methods and resultsWe studied 53 plasma and 20 myocardial samples from 19 patients who underwent HeartMate II LVAD implantation, and used a screening microarray to analyse the change in expression of 1113 miRs after 6 months LVAD support. Twelve miRs showed significant variation and underwent validation, yielding miR‐1202 and miR‐483‐3p as candidate biomarkers. In the test cohort, circulating miR‐483‐3p showed early and sustained up‐regulation with LVAD support, with median (interquartile range) fold changes from baseline of 2.17 (1.43–2.62; P = 0.011), 2.27 (1.12–2.42; P = 0.036), 1.87 (1.64–4.36; P = 0.028), and 2.82 (0.70–10.62; P = 0.249) at 3, 6, 9, and 12 months, respectively, whilst baseline plasma miR‐1202 identified good vs. poor LVAD responders [absolute expression 1.296 (1.293–1.306) vs. 1.311 (1.310–1.318) arbitrary units; P = 0.004]. Both miRs are enriched in ventricular myocardium, suggesting the heart as the possible source of the plasma fraction.ConclusionsThis is the first report of circulating miR biomarkers in LVAD patients. We demonstrate the feasibility of this approach, report the potential for miR‐483‐3p and miR‐1202, respectively, to monitor and predict response to LVAD therapy, and propose further work to study these hypotheses and elucidate roles for miR‐483‐3p and miR‐1202 in clinical practice and in underlying biological processes.
A Trinuclear Zinc–Schiff Base Complex: Biocatalytic Activity and Cytotoxicity
Authors: Dey Dhananjay , Kaur Gurpreet , Ranjani Anandan , Gayathri Loganathan , Chakraborty Prateeti , Adhikary Jaydeep , Pasan Jorge , Dhanasekaran Dharumadurai , Choudhury Angshuman R. , Akbarsha Mohammad A. , Kole Niranjan , Biswas Bhaskar 
Published: June 2014

AbstractA novel trinuclear zinc(II) complex [Zn3L2(μ‐O2CCH3)2(CH3OH)4] (1) that contains an N,O‐donor Schiff base ligand {H2L = 2‐[(2‐hydroxyphenylimino)methyl]‐6‐methoxyphenol} has been synthesized and crystallographically characterized. The X‐ray crystal structure of 1 contains three zinc(II) centers, which have distorted‐octahedral coordination geometry, and the molecule crystallizes in the Pbcn space group. The zinc(II) complex displays significant catecholase oxidation activity in methanolic medium through a ligand‐centered radical pathway. This is the first example of catecholase oxidation through a trinuclear zinc(II)–Schiff base complex by means of the formation of a mononuclear intermediate as [ZnL(dtbc)] (dtbc = 3,5‐di‐tert‐butylcatechol). The fluorescence property of 1 indicates that it can serve as a potential photoactive material. It effectively cleaves the double strand of pBR 322 plasmid DNA at a given concentration (25 μM). The complex shows remarkable cytotoxicity against a human hepatocarcinoma cell line (HepG2).
Structural and Electrochemical Studies of Copper(I) Complexes with Diethoxyphosphoryl‐1,10‐phenanthrolines
Authors: Mitrofanov Alexander , Manowong Machima , Rousselin Yoann , Brandès Stéphane , Guilard Roger , Bessmertnykh‐Lemeune Alla , Chen Ping , Kadish Karl M. , Goulioukina Nataliya , Beletskaya Irina 
Published: June 2014

AbstractTwo series of copper(I) complexes with diethoxyphosphoryl‐substituted 1,10‐phenanthroline ligands were synthesized and characterized in the solid state and in solution. The first comprised mixed‐ligand CuI complexes with phenanthroline and triphenylphosphine. The second series includes bis‐chelates with two phenanthroline ligands. According to the X‐ray data for the six complexes, the ditopic phenanthroline ligands exhibit bidentate coordination to the copper(I) atom through two nitrogen atoms in both series. Solution equilibria involving different phenanthroline copper(I) species were studied by 1H and 31P NMR spectroscopy, electrochemistry, and spectroelectrochemistry. The solution speciation of these labile complexes is different for these two series and depends on the nature of solvent and the location of the phosphorus substituent on the phenanthroline backbone. Coordinating solvents can replace a bromide, triphenylphosphine, and even a phenanthroline ligand in the inner coordination sphere of the metal center. Copper(I) complexes with α‐substituted phenanthrolines easily dissociate even in noncoordinating solvents such as CH2Cl2 and CHCl3. Ligand‐exchange reactions leading to less sterically hindered species were observed under the utilized solution conditions. The coordination mode of the phenanthroline chelators does not change under any of the utilized solution conditions, and binding of the phosphoryl group to the metal center was never observed by spectroscopic or spectroelectrochemical methods.
A NiII–Bis(diphosphine)–Hydride Complex Containing Proton Relays – Structural Characterization and Electrocatalytic Studies
Authors: Das Parthapratim , Stolley Ryan M. , van der Eide Edwin F. , Helm Monte L. 
Published: June 2014

AbstractThe synthesis of the 1,5‐diphenyl‐3,7‐diisopropyl‐1,5‐diaza‐3,7‐diphosphacyclooctane ligand, PiPr2NPh2, is reported. Two equivalents of the ligand react with [Ni(CH3CN)6](BF4)2 to form the bis(diphosphine)–NiII complex [Ni(PiPr2NPh2)2](BF4)2, which acts as a proton reduction electrocatalyst. In addition to [Ni(PiPr2NPh2)2]2+, we report the synthesis and structural characterization of the Ni0 complex Ni(PiPr2NPh2)2 and the NiII–hydride complex [HNi(PiPr2NPh2)2]BF4. The [HNi(PiPr2NPh2)2]BF4 complex represents the first NiII–hydride in the [Ni(PR2NR′2)2]2+ family of compounds to be structurally characterized. In addition to the experimental data, the mechanism of electrocatalysis facilitated by [Ni(PiPr2NPh2)2]2+ is analyzed by using linear free energy relationships recently established for the [Ni(PR2NR′2)2]2+ family.
Tuning the Electronic Properties of Piezoresistive Bilayer Films Based on α‐(BEDT‐TTF)2I3
Authors: Lebedev Victor , Laukhina Elena , Laukhin Vladimir , Rovira Concepció , Veciana Jaume 
Published: June 2014

AbstractWe present a study of the influence of the iodine/solvent annealing temperature on the properties of piezoresistive bilayer films with layers of α‐(BEDT‐TTF)2I3 [BEDT‐TTF = bis(ethylenedithio)tetrathiafulvalene]. The formation of the conductive layers was tested by XRD, direct current (dc) conductivity measurements, and SEM, and the electromechanical properties have also been studied. We demonstrate that it is possible to form bilayer (BL) films with an invariant gauge factor of ca. 10 but with the temperature dependence of the resistance variable from metallic to semiconductor‐like by control of the annealing temperature. This control even permits the preparation of a BL film with temperature‐independent resistance.
A Facile Route for Stabilizing Highly Reactive ArTeCl Species Through the Formation of T‐Shaped Tellurenyl Chloride Adducts:quasi‐Planar Zwitterionic [HPy*]TeCl2and [HPm*]TeCl2; Py* = 2‐pyridyl, Pm* = 2‐(4,6‐dimethyl)pyrimidyl
Authors: Khrustalev Victor N. , Matsulevich Zhanna V. , Lukiyanova Julia M. , Aysin Rinat R. , Peregudov Alexander S. , Leites Larissa A. , Borisov Alexander V. 
Published: June 2014

AbstractTwo new stable T‐shaped tellurenyl chloride adducts, viz., [HPy*]TeCl2(1) and [HPm*]TeCl2(2) [Py* = 2‐pyridyl, Pm* = 2‐(4,6‐dimethyl)pyrimidyl], act as close chemical analogs of highly unstable monomeric Py*TeCl and Pm*TeCl. Thequasi‐planar zwitterionic structures of1and2have been studied by experimental (X‐ray diffraction, multinuclear NMR, IR and Raman spectroscopy) and theoretical (DFT and QTAIM) methods. Thus, a novel facile route to stabilize highly reactive Ar*TeCl species (Ar* =N‐functionalized aryl) by the addition of a hydrochloric acid molecule has been demonstrated.
Mechanistic Insights into the Palladium‐Catalyzed Domino Synthesis of 10,11‐Dihydro‐5H‐dibenzo[b,e][1,4]diazepines
Authors: Laha Joydev K. , Satyanarayana Tummalapalli K. S. , Gupta Ankur 
Published: June 2014

AbstractA palladium‐catalyzed domino approach to the synthesis of 10,11‐dihydro‐5H‐dibenzo[b,e][1,4]diazepines starting from o‐phenylenediamines and 2‐bromobenzyl bromides or tosylates has been developed. Mechanistic studies support the following domino sequence. Intermolecular mono‐N‐benzylation of the o‐phenylenediamine through oxidative palladium insertion, primarily at the benzylic position of the 2‐bromobenzyl bromide, is followed by intramolecular N′‐arylation. The intramolecular N′‐arylation is demonstrated to be facilitated by coordination of a remote auxiliary nitrogen atom to the palladium atom.
Carbene‐Catalyzed Aroylation of a 2‐Chloroquinoxaline N‐Oxide with Aromatic Aldehydes at Room Temperature
Authors: Maichrowski Jan , Bhasin Aman , Sasse Florenz , Kaufmann Dieter E. 
Published: June 2014

AbstractStarting from easily accessible 2‐chloro‐3‐(cyclopentyloxy)‐7‐fluoroquinoxaline 1‐oxide, 12 new biologically promising aroylquinoxaline N‐oxides were synthesized through carbene‐catalyzed aroylation of the chloro nitrone unit with different aromatic aldehydes in the presence of 1,3‐dimethylimidazolium iodide as the carbene precursor. The optimized reaction conditions tolerated a broad bandwidth of aldehydes and allowed the synthesis of the corresponding ketones in yields up to 87 %. Studies of their biological activities resulted in interesting specific cytotoxic effects against tumor cell lines.
Protecting‐Group‐Free Solid‐Phase Anchoring of Polyphenolic C‐Glucosidic Ellagitannins and Synthesis of 1‐Alkylamino‐Vescalagin Derivatives
Authors: Douat Céline , Berni Emanuela , Jacquet Rémi , Pouységu Laurent , Deffieux Denis , Quideau Stéphane 
Published: June 2014

AbstractThe C‐glucosidic ellagitannins vescalagin and vescalin are among the plant polyphenols that have been shown to interact with protein targets in a specific manner. This work describes a protecting‐group‐free method to immobilize these protein‐binding natural products on a solid support, and a functionalizing cleavage method, which is adaptable to the solution‐phase synthesis of vescal(ag)in derivatives, and which advantageously permitted the preparation of 1‐alkylamino derivatives of vescalagin.
A Unified Strategy for Kainoid Synthesis
Authors: Fujii Masaya , Yokoshima Satoshi , Fukuyama Tohru 
Published: June 2014

AbstractA unified strategy for kainoid synthesis was developed. The key features of the strategy involve a Claisen–Ireland rearrangement to construct the contiguous stereogenic centers and a palladium‐catalyzed formation of the pyrrolidine ring with complete stereoselectivity. The present protocol has enabled rapid access to a wide range of kainoids with diverse types of substituents (alkenyl, aryl, and alkyl groups) at the 4‐position of the pyrrolidine ring, starting from the common intermediate and appropriate acetic acid derivatives. To test the generality of the strategy, we have accomplished the syntheses of kainic acid, o‐methoxyphenyl derivative (MFPA), and a novel cyclopropyl derivative (CPKA), using 3‐methylbut‐3‐enoic acid, 2‐(2‐methoxyphenyl)acetic acid, and 2‐cyclopropylacetic acid, respectively.
Assignment of the Absolute Configuration and Total Synthesis of (+)‐Caripyrin
Authors: Andernach Lars , Opatz Till 
Published: June 2014

AbstractThe antifungal secondary metabolite (+)‐caripyrin was studied by vibrational circular dichroism spectroscopy. Analysis of the recorded data, with the Boltzmann weighted‐average of the spectra calculated at the B3LYP/6‐311G(d,p) level of theory for all relevant conformers, unequivocally proved the (R,R)‐configuration for the dextrorotatory natural product. Based on this finding, a short enantioselective synthesis of (+)‐caripyrin was developed.
Diazocines on Molecular Platforms
Authors: Tellkamp Tobias , Shen Jun , Okamoto Yoshio , Herges Rainer 
Published: June 2014

AbstractNew diazocines as photochromic switches for the surface functionalization via the “platform approach” were synthesized and characterized. Symmetric diazocines as well as asymmetric molecules based on an indane scaffold were obtained and their photochromic properties were investigated. In a final step, the diazocines were mounted on molecular platforms (triazatriangulenium ions).
Selective Synthesis of Tetrasubstituted 4‐(Tetrazol‐5‐yl)‐1H‐imidazoles from 2‐(Tetrazol‐5‐yl)‐2H‐azirines
Authors: Cardoso Ana Lúcia , Lemos Américo , Pinho e Melo Teresa M. V. D. 
Published: June 2014

AbstractThe reactivity of 2‐(tetrazol‐5‐yl)‐2H‐azirines towards imines in the presence of Lewis acids was explored, which opened a way to new tetrazol‐5‐yl‐1H‐imidazole derivatives. The Zn(OTf)2‐catalyzed reaction allowed the selective synthesis of 4‐(tetrazol‐5‐yl)‐1H‐imidazole derivatives. The presence of phenyl or heteroaromatic substituents in both reactants permitted the synthesis of a wide range of multisubstituted imidazoles, which are molecules with potential relevance in medicinal chemistry.