bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct Bio‐electrocatalysis of O2 Reduction by Streptomyces coelicolor Laccase Orientated at Promoter‐Modified Graphite Electrodes
Authors: Lörcher Samuel , Lopes Paula , Kartashov Andrey , Ferapontova Elena E. 
Published: April 2013

AbstractBacterial laccase from Streptomyces coelicolor (SLAC) has been immobilised and orientated at promoter (pyrene and neocuproine)‐modified electrodes productively both for direct electron transfer (ET) between the electrode and the T1 Cu site of SLAC and direct (unmediated) bio‐electrocatalysis of dioxygen reduction. Its T1 Cu potential ranges between 471 and 318 mV versus the normal hydrogen electrode, at pH 5.5 and 8, respectively; this value is dependent both on the solution pH and electrode modification. In the presence of O2, Cu of the T2/T3 trinuclear centre is distinguished electrochemically at 748–623 mV. Depending on the promoter nature, different orientations of SLAC at pyrene‐ and neocuproine‐modified electrodes can be followed from the kinetic analysis of the ET rates. Bio‐electrocatalytic reduction of oxygen starts from the T1 Cu potentials of SLAC, and is most efficient at the promoter‐modified electrodes, thereby demonstrating good performance both in neutral and basic media and in solutions with a high NaCl content, such as sea water. The obtained results allow consideration of a broader bioenergetic application of laccases as biocathodes operating directly in such environmental media as sea water and physiological fluids.
Electron Interference in Molecular Photoionization by Attosecond Laser Pulses
Authors: Yuan Kai‐Jun , Lu Huizhong , Bandrauk André D. 
Published: April 2013

AbstractMolecular photoionization by intense attosecond linearly and circularly polarized X‐ray laser pulses is investigated from numerical solutions of time‐dependent Schrödinger equations for the one‐electron systems H2+ and H3++. Both momentum stripes and rings in photoelectron angular distributions are observed. The first with momentum intervals Δps=2 π/R, where R is the molecular internuclear distance, results from interference of the coherent continuum scattering electron wave packets, which is shown to be insensitive to the laser polarization and wavelength. Diffraction of the directly ionized electrons leads to the momentum rings defined by the angle ${\theta _{p^r R} = \cos ^{ - 1} \left( {2n\pi } \right)/p^r R}$ between the electron momentum pr and the molecular internuclear R axis. These patterns are well described by multi‐center interference models. Such complex patterns allow us to probe intermolecular structures.
Parkinson Disease and Exercise
Authors: Earhart Gammon M. , Falvo Michael J. 
Published: April 2013

AbstractParkinson disease (PD) is a progressive, neurodegenerative movement disorder. PD was originally attributed to neuronal loss within the substantia nigra pars compacta, and a concomitant loss of dopamine. PD is now thought to be a multisystem disorder that involves not only the dopaminergic system, but other neurotransmitter systems whose role may become more prominent as the disease progresses (). PD is characterized by four cardinal symptoms, resting tremor, rigidity, bradykinesia, and postural instability, all of which are motor. However, PD also may include any combination of a myriad of nonmotor symptoms (). Both motor and nonmotor symptoms may impact the ability of those with PD to participate in exercise and/or impact the effects of that exercise on those with PD. This article provides a comprehensive overview of PD, its symptoms and progression, and current treatments for PD. Among these treatments, exercise is currently at the forefront. People with PD retain the ability to participate in many forms of exercise and generally respond to exercise interventions similarly to age‐matched subjects without PD. As such, exercise is currently an area receiving substantial research attention as investigators seek interventions that may modify the progression of the disease, perhaps through neuroprotective mechanisms. © 2013 American Physiological Society.Compr Physiol3:833‐848, 2013.
Liver Immunology
Authors: Bogdanos Dimitrios P. , Gao Bin , Gershwin M. Eric 
Published: April 2013

AbstractThe liver is the largest organ in the body and is generally regarded by nonimmunologists as having little or no lymphoid function. However, such is far from accurate. This review highlights the importance of the liver as a lymphoid organ. Firstly, we discuss experimental data surrounding the role of liver as a lymphoid organ. The liver facilitates tolerance rather than immunoreactivity, which protects the host from antigenic overload of dietary components and drugs derived from the gut and it is instrumental to fetal immune tolerance. Loss of liver tolerance leads to autoaggressive phenomena, which if not controlled by regulatory lymphoid populations, may lead to the induction of autoimmune liver diseases. Liver‐related lymphoid subpopulations also act as critical antigen‐presenting cells. The study of the immunological properties of liver and delineation of the microenvironment of the intrahepatic milieu in normal and diseased livers provides a platform to understand the hierarchy of a series of detrimental events that lead to immune‐mediated destruction of the liver and the rejection of liver allografts. The majority of emphasis within this review will be on the normal mononuclear cell composition of the liver. However, within this context, we will discuss selected, but not all, immune‐mediated liver disease and attempt to place these data in the context of human autoimmunity. © 2013 American Physiological Society.Compr Physiol3:567‐598, 2013.
Renal Vascular Structure and Rarefaction
Authors: Chade Alejandro R. 
Published: April 2013

AbstractAn intact microcirculation is vital for diffusion of oxygen and nutrients and for removal of toxins of every organ and system in the human body. The functional and/or anatomical loss of microvessels is known as rarefaction, which can compromise the normal organ function and have been suggested as a possible starting point of several diseases. The purpose of this overview is to discuss the potential underlying mechanisms leading to renal microvascular rarefaction, and the potential consequences on renal function and on the progression of renal damage. Although the kidney is a special organ that receives much more blood than its metabolic needs, experimental and clinical evidence indicates that renal microvascular rarefaction is associated to prevalent cardiovascular diseases such as diabetes, hypertension, and atherosclerosis, either as cause or consequence. On the other hand, emerging experimental evidence using progenitor cells or angiogenic cytokines supports the feasibility of therapeutic interventions capable of modifying the progressive nature of microvascular rarefaction in the kidney. This overview will also attempt to discuss the potential renoprotective mechanisms of the therapeutic targeting of the renal microcirculation. © 2013 American Physiological Society.Compr Physiol3:817‐831, 2013.
Immune and Inflammatory Role in Renal Disease
Authors: Imig John D. , Ryan Michael J. 
Published: April 2013

Abstract

Chronic and acute renal diseases, irrespective of the initiating cause, have inflammation and immune system activation as a common underlying mechanism. The purpose of this review is to provide a broad overview of immune cells and inflammatory proteins that contribute to the pathogenesis of renal disease, and to discuss some of the physiological changes that occur in the kidney as a result of immune system activation. An overview of common forms of acute and chronic renal disease is provided, followed by a discussion of common therapies that have anti‐inflammatory or immunosuppressive effects in the treatment of renal disease. © 2013 American Physiological Society.
Compr Physiol
3:957‐976, 2013.
Lanthanide‐Functionalized SBA‐15 Mesoporous Hybrids – Ultraviolet‐Visible Excitation and Visible–NIR Emission
Authors: Gu Yan‐Jing , Yan Bing 
Published: April 2013

Abstract9‐Hydroxy‐2‐methyl‐phenalenone (MHPO) was synthesized and modified with 3‐(triethoxysilyl)propyl isocyanate (TEPIC) through a hydrogen atom addition reaction to achieve a new chemical linkage (named as MHPOSi). SBA‐15 mesoporous silica organically functionalized with MHPOSi was synthesized. The MHPOSi was linked to tetraethoxysilane (TEOS) through a condensation process in the presence of Pluronic P123 surfactant as a template. New Ln3+ (Eu3+, Nd3+, Yb3+) organic–inorganic mesoporous hybrid materials were prepared, in which the Ln3+ complexes are covalently attached to SBA‐15 and have 1,10‐phenanthroline (phen) as a second ligand. The resultant mesoporous hybrids were characterized by FTIR spectroscopy, small‐angle X‐ray diffraction, N2 adsorption–desorption measurements, thermal analysis, and UV/Vis spectroscopy. They all have high surface areas, uniform mesostructures, and good crystallinity. The photophysical properties of the functionalized mesoporous SBA‐15 networks are discussed in detail and they still present excitation capability in the visible region despite the modification of the organic silane. Subsequently, they exhibit characteristic visible (Eu3+) and near‐infrared (NIR) luminescence (Nd+ and Yb3+).
Concise Chemoenzymatic Three‐Step Total Synthesis of Isosolenopsin through Medium Engineering
Authors: Simon Robert C. , Fuchs Christine S. , Lechner Horst , Zepeck Ferdinand , Kroutil Wolfgang 
Published: April 2013

AbstractA short and efficient total synthesis of the alkaloid isosolenopsin and its enantiomer has been achieved. The key step was a ω‐transaminase‐catalysed regioselective monoamination of the diketone pentadecane‐2,6‐dione, which was obtained in a single step through the application of a Grignard reaction. Initial low conversions in the biotransformation could be overcome by optimisation of the reaction conditions employing suitable cosolvents. In the presence of 20 vol.‐% N,N‐dimethylformamide (DMF) or n‐heptane the best results were obtained by employing two enantiocomplementary ω‐transaminases originating from Arthrobacter at 30–40 °C; under these conditions, conversions of more than 99 % and perfect stereocontrol (ee > 99 %) were achieved. Diastereoselective chemical reduction (H2/Pd/C) of the biocatalytic product gave the target compound. The linear three‐step synthesis provided the natural product isosolenopsin in diastereomerically pure form (ee > 99 %, dr = 99:1) with an overall yield of 64 %.
Conithiaquinones A and B, Tetracyclic Cytotoxic Meroterpenes from the Mediterranean Ascidian Aplidium conicum
Authors: Menna Marialuisa , Aiello Anna , D'Aniello Filomena , Imperatore Concetta , Luciano Paolo , Vitalone Rocco , Irace Carlo , Santamaria Rita 
Published: April 2013

AbstractChemical investigation of the Mediterranean ascidian A. conicum resulted in the isolation of two new meroterpenes, the conithiaquinones A (1) and B (2), in addition to two previously reported chromenols (3 and 4) and conicaquinones (5 and 6). The structures of conithiaquinones A and B were determined by interpretation of spectroscopic data, and regiochemical and stereochemical assignments were achieved with the aid of computational methods, including the recently developed DP4 NMR spectral prediction method. Both conithiaquinones A and B showed significant effects on the growth and viability of cells, with 1 showing interesting cytotoxicity against human breast cancer cells.
Highly Selective and Sensitive Graphene Based Electrochemical Sensor for Quantification of Receptor Agonist Rizatriptan
Authors: Jain Rajeev , Tiwari D.C , Pandey Preeti 
Published: April 2013

AbstractA highly selective and sensitive electrochemical sensor has been developed by modification of a glassy carbon electrode (GCE) with graphene (GRP) for quantification of Rizatriptan. The significant increase of the peak current and the improvement of the oxidation peak potential indicate that the electrochemical sensor facilitates the electron transfer of Rizatriptan. The oxidation peak current was proportional to the Rizatriptan concentration in the range from 100 to 600 µg/mL with detection (LOD) and quantification limit (LOQ) of 36.52 and 121.73 µg/mL, respectively. The developed method was successfully employed for quantification of Rizatriptan in pharmaceutical formulations. The sensor shows great promise for simple, sensitive and quantitative detection of Rizatriptan.
Assessment of stretched vortex subgrid‐scale models for LES of incompressible inhomogeneous turbulent flow
Authors: Shetty Dinesh A. , Frankel Steven H. 
Published: April 2013

SUMMARYThe physical space version of the stretched vortex subgrid scale model is tested in LES of the turbulent lid‐driven cubic cavity flow. LES is carried out by using a higher order finite‐difference method. The effects of different vortex orientation models and subgrid turbulence spectrums are assessed through comparisons of the LES predictions against DNS. Three Reynolds numbers 12000, 18000, and 22000 are studied. Good agreement with the DNS data for the mean and fluctuating quantities is observed. Copyright © 2013 John Wiley & Sons, Ltd.
Blood pro‐inflammatory cytokines in Alzheimer's disease in relation to the use of acetylcholinesterase inhibitors
Authors: Richardson Cassandra , Gard Paul R. , Klugman Anthony , Isaac Mokhtar , Tabet Naji 
Published: April 2013

ObjectiveA potential anti‐inflammatory role for acetylcholinesterase inhibitors (AChEIs) has been supported by animal studies. As very limited data exist from individuals with Alzheimer's disease (AD), the aim of this study was to assess the potential influence of AChEIs on blood pro‐inflammatory cytokines. We hypothesized that pro‐inflammatory cytokine concentrations were lower in individuals with AD stabilized on AChEIs.MethodsBlood interleukin‐1 beta, interleukin‐6, and tumor necrosis factor‐alpha concentrations were assessed using specific enzyme‐linked immunosorbent assays in three groups of participants: patients with AD stabilized on a therapeutic dose of an AChEI (n = 42); AChEIs drug naïve patients (n = 24); and a cognitively unimpaired control group (n = 35). Patients in the AChEIs group had received medication for an average of one year.ResultsPatients stabilized on an AChEI did not differ significantly from drug naïve patients in relation to the concentrations of interleukin‐1 beta, interleukin‐6, and tumor necrosis factor‐alpha (p = 0.874, 0.225, and 0.978, respectively). Within the group taking AChEIs, the levels of cytokines did not differ between those taking donepezil, rivastigmine, or galantamine (p = 0.368, 0.851, and 0.299, respectively).ConclusionsResults from animal studies suggesting a modulatory anti‐inflammatory role for AChEIs was not advanced in this study. In individuals with AD, very limited evidence currently exists to support the hypothesis that AChEIs may influence inflammatory blood markers and function beyond the enhancement of neuronal transmission. However, further studies assessing a wider range of inflammatory markers and processes are still needed before this hypothesis can be ruled out. Copyright © 2013 John Wiley & Sons, Ltd.
An experimental study of the influence of graphite on the electrical conductivity of olivine aggregates
Authors: Wang Duojun , Karato Shun‐ichiro , Jiang Zhenting 
Published: April 2013

AbstractPresence of graphite is one of the mechanisms to explain enhanced electrical conductivity. Because the conductivity of graphite is highly anisotropic and the connectivity of graphite depends strongly on the geometry of the crystals, the key issue is the geometry of graphite in a rock including their crystallographic orientation and the shape of graphite crystals. We explored the role of graphite on electrical conductivity in olivine‐rich aggregates. To obtain well‐defined results, we conducted an experimental study at high pressure and temperature conditions. Olivine aggregates containing diamonds were annealed to transform diamond to graphite with nearly equilibrium morphology. Graphite formed by the transformation from diamond has thin disk‐shape morphology, the plane being the highly conductive (0001) plane. When the concentration of graphite exceeds the percolation threshold (~ 1 wt%), electrical conductivity is significantly enhanced. Some of the observed high conductivity regions may represent regions of high concentration of graphite.
Buoyant currents arrested by convective dissolution
Authors: MacMinn Christopher W. , Juanes Ruben 
Published: April 2013

AbstractWhen carbon dioxide (CO2) dissolves into water, the density of water increases. This seemingly insubstantial phenomenon has profound implications for geologic carbon sequestration. Here we show, by means of laboratory experiments with analog fluids, that the up‐slope migration of a buoyant current of CO2 is arrested by the convective dissolution that ensues from a fingering instability at the moving CO2‐groundwater interface. We consider the effectiveness of convective dissolution as a large‐scale trapping mechanism in sloping aquifers, and we show that a small amount of slope is beneficial compared to the horizontal case. We study the development and coarsening of the fingering instability along the migrating current and predict the maximum migration distance of the current with a simple sharp‐interface model. We show that convective dissolution exerts a powerful control on CO2 plume dynamics and, as a result, on the potential of geologic carbon sequestration.
Deducing the spatial variability of exchange within a longitudinal channel water balance
Authors: Schmadel Noah M. , Neilson Bethany T. , Kasahara Tamao 
Published: April 2013

AbstractDeveloping an appropriate data collection scheme to infer stream–subsurface interactions is not trivial due to the spatial and temporal variability of exchange flowpaths. Within the context of a case study, this paper presents the results from a number of common data collection techniques ranging from point to reach scales used in combination to better understand the spatial complexity of subsurface exchanges, infer the hydrologic conditions where individual influences of hyporheic and groundwater exchange components on stream water can be characterized, and determine where gaps in information arise. We start with a tracer‐based, longitudinal channel water balance to quantify hydrologic gains and losses at a sub‐reach scale nested within two consecutive reaches. Next, we look at groundwater and stream water surface levels, shallow streambed vertical head gradients, streambed and aquifer hydraulic conductivities, water chemistry, and vertical flux rates estimated from streambed temperatures to provide more spatially explicit information. As a result, a clearer spatial understanding of gains and losses was provided, but some limitations in interpreting results were identified even when combining information collected over various scales. Due to spatial variability of exchanges and areas of mixing, each technique frequently captured a combination of groundwater and hyporheic exchange components. Ultimately, this study provides information regarding technique selection, emphasizes that care must be taken when interpreting results, and identifies the need to apply or develop more advanced methods for understanding subsurface exchanges. Copyright © 2013 John Wiley & Sons, Ltd.
Quantification of doxorubicin in biofluids using white light excitation fluorescence
Authors: Prakash John , Mishra Ashok Kumar 
Published: April 2013

AbstractA fiber optic spectrometer setup was designed for white light excitation fluorescence ‘WLEF’ based measurements. Using this setup, two different analytical methods, a self referencing ratio‐metric and a difference WLEF methods, were developed for the quantification of doxorubicin (DXR) in biofluids. It was seen that Acetonitrile (ACN) acts as an efficient and transparent extracting medium for DXR. The figures of merit and the percent recoveries of DXR in blood serum, even in presence of external fluorophores and in urine samples are comparable with existing analytical methods. The compact spectrometer is expected to be useful for easy quantification of fluorescent pharmaceuticals in biofluids. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Facile One‐pot Synthesis of Substituted Dihydropyrrol‐2‐ones via Four‐component Domino Reaction of Amines, Dialkyl Acetylenedicarboxylates and Formaldehyde
Authors: Sajadikhah Seyed Sajad , Hazeri Nourallah , Maghsoodlou Malek Taher , Habibi‐Khorassani Sayyed Mostafa 
Published: April 2013

AbstractA mild and efficient method for the one‐pot synthesis of substituted dihydropyrrol‐2‐one derivatives is described via four‐component domino reaction of amines, dialkyl acetylenedicarboxyaltes and formaldehyde in the presence of 1‐methyl‐2‐oxopyrrolidinium hydrogen sulfate ([Hpyro][HSO4]) as ionic liquid catalyst. This facile approach proceeded smoothly in good to high yields and pure products are separated from the reaction mixture by simple filtration.
Targeting deregulated epigenetic control in cancer
Authors: Zaidi Sayyed K. , Van Wijnen Andre J. , Lian Jane B. , Stein Janet L. , Stein Gary S. 
Published: April 2013

AbstractCancer is a multifaceted disease that involves acquisition of genetic mutations, deletions, and amplifications as well as deregulation of epigenetic mechanisms that fine‐tune gene regulation. Key epigenetic mechanisms that include histone modifications, DNA methylation, and non‐coding RNA‐mediated gene silencing are often deregulated in a variety of cancers. Subnuclear localization of key proteins in the interphase nucleus and bookmarking of genes by lineage commitment factors in mitosis—a new dimension to epigenetic control of fundamental biological processes—is also modified in cancer. In this review, we discuss the various aspects of epigenetic control that are operative in a variety of cancers and their potential for risk assessment, early detection, targeted therapy, and personalized medicine. J. Cell. Physiol. 228: 2103–2108, 2013. © 2013 Wiley Periodicals, Inc.
Hyperpolarized 3He and 129Xe MRI: Differences in asthma before bronchodilation
Authors: Svenningsen Sarah , Kirby Miranda , Starr Danielle , Leary Del , Wheatley Andrew , Maksym Geoffrey N. , McCormack David G. , Parraga Grace 
Published: April 2013

PurposeTo compare hyperpolarized helium‐3 (3He) and xenon‐129 (129Xe) MRI in asthmatics before and after salbutamol inhalation.Materials and MethodsSeven asthmatics provided written informed consent and underwent spirometry, plethysmography, and MRI before and after salbutamol inhalation. 3He and 129Xe ventilation defect percent (VDP) and ventilation coefficient of variation (COV) were measured. To characterize the airways spatially related to ventilation defects, wall area percent (WA%) and lumen area (LA) were evaluated for two subjects who had thoracic x‐ray computed tomography (CT) acquired 1 year before MRI.ResultsBefore salbutamol inhalation, 129Xe VDP (8 ± 5%) was significantly greater than 3He VDP (6 ± 5%, P = 0.003). Post‐salbutamol, there was a significant improvement in both 129Xe (5 ± 4%, P < 0.0001) and 3He (4 ± 3%, P = 0.001) VDP, and the improvement in 129Xe VDP was significantly greater (P = 0.008). 129Xe MRI COV (Pre: 0.309 ± 0.028, Post: 0.296 ± 0.036) was significantly greater than 3He MRI COV (Pre: 0.282 ± 0.018, Post: 0.269 ± 0.024), pre‐ (P < 0.0001) and post‐salbutamol (P < 0.0001) and the decrease in COV post‐salbutamol was significant (129Xe, P = 0.002; 3He, P < 0.0001). For a single asthmatic, a sub‐segmental 129Xe MRI ventilation defect that was visible only before salbutamol inhalation but not visible using 3He MRI was spatially related to a remodeled fourth generation sub‐segmental airway (WA% = 78%, LA = 2.9 mm2).ConclusionIn asthma, hyperpolarized 129Xe MRI may help reveal ventilation abnormalities before bronchodilation that are not observed using hyperpolarized 3He MRI. J. Magn. Reson. Imaging 2013;38:1521–1530. © 2013 Wiley Periodicals, Inc.