bluuebunny/crossref_metadata_2025 huggingface dataset:
MULTIWAVELENGTH OBSERVATIONS OF PKS 0528+134 IN QUIESCENCE
Authors: BÖTTCHER MARKUS , PALMA NORMAN
Published: April 2012

We present results of multiwavelength observations of the ultraluminous radio-loud quasar PKS 0528+134 in quiescence in the Fall of 2009. Significant flux variability on a time-scale of several hours was found in the optical regime, accompanied by a weak trend of spectral softening with increasing flux. The optical flux is weakly polarized with rapid variations of the degree and direction of polarization. Optical spectropolarimetry suggests a trend of increasing degree of polarization with increasing wavelength. Together with the spectral variability, this provides evidence for an unpolarized, slowly variable emission component, possibly thermal emission from the accretion disk, contributing towards the blue end of the optical spectrum.

We find that even in the quiescent state, the bolometric luminosity of PKS 0528+134 is dominated by its γ-ray emission. A leptonic single-zone jet model produced acceptable fits to the SEDs with contributions to the high-energy emission from both synchrotron self-Compton radiation and Comptonization of direct accretion disk emission. The moderate variability on long time scales, compared to the expected radiative cooling time scales, implies the existence of on-going particle acceleration, while the observed optical polarization variability seems to point towards a turbulent acceleration process.
PARSEC-SCALE JET BEHAVIOR OF THE QUASAR 3C273 DURING A HIGH GAMMA-RAY STATE IN 2009–2010
Authors: JORSTAD S. , MARSCHER A. , SMITH P. , LARIONOV V. , AGUDO I. , GÓMEZ J. L. , CASADIO C. , MOLINA S. , GURWELL M.
Published: April 2012

We analyze total and polarized intensity images of the quasar 3C273 obtained at 43 GHz monthly during 2008-2010 with the VLBA. We find a strong increase of activity in the parsec-scale jet during a high γ-ray state lasting from 2009 June to 2010 May featuring an increase of the total and polarized flux in the mm-wave core and the appearance of superluminal knots in the jets. Although the optical variability is low, owing to strong contamination by the big blue bump, we observe an increase in optical polarization by a factor of 3 during a gamma-ray flare in 2010 April. We discuss the locations in the jet where high gamma-ray fluxes occur. These include stationary features in the jet flow that we identify with standing shocks.
AUTOMATIC QUENCHING OF γ-RAY EMISSION IN COMPACT ASTROPHYSICAL SOURCES
Authors: PETROPOULOU MARIA , MASTICHIADIS APOSTOLOS
Published: April 2012

We investigate automatic γ-ray photon quenching in compact non-thermal sources. This is an auto-regulating network of processes that consists of photon-photon absorption and synchrotron emission of the produced e- e+ pairs and operates non linearly whenever the γ-ray luminosity exceeds a critical value. We present expressions for this quantity and discuss our results.
JETS AND OUTFLOWS IN RADIO GALAXIES: IMPLICATIONS FOR AGN FEEDBACK
Authors: TORRESI ELEONORA , GRANDI PAOLA , COSTANTINI ELISA , PALUMBO GIORGIO G. C.
Published: April 2012

One of the main debated astrophysical problems is the role of the AGN feedback in galaxy formation. It is known that massive black holes have a profound effect on the formation and evolution of galaxies, but how black holes and galaxies communicate is still an unsolved problem. For Radio Galaxies, feedback studies have mainly focused on jet/cavity systems in the most massive and X–ray luminous galaxy clusters. The recent high–resolution detection of warm absorbers in some Broad Line Radio Galaxies allow us to investigate the interplay between the nuclear engine and the surrounding medium from a different perspective. We report on the detection of warm absorbers in two Broad Line Radio Galaxies, 3C 382 and 3C 390.3, and discuss the physical and energetic properties of the absorbing gas. Finally, we attempt a comparison between radio–loud and radio–quiet outflows.
ANISOTROPIC SCATTERING FROM THE CIRCUMSTELLAR DISC IN PSR B1259-63
Authors: VAN SOELEN B. , MEINTJES P. J.
Published: April 2012

The gamma-ray binary system PSR B1259-63 has recently passed through periastron and has been of particular interest as it was observed by Fermi near the December 2010 periastron passage. The system has been detected at very high energies with H.E.S.S. The most probable production mechanism is inverse Compton scattering between target photons from the optical companion and disc, and relativistic electrons in the pulsar wind. We present results of a full anisotropic inverse Compton scattering model of the system, taking into account the IR excess from the extended circumstellar disc around the optical companion.
Epinephrine and AICAR-induced PGC-1α mRNA expression is intact in skeletal muscle from rats fed a high-fat diet
Authors: Frier Bruce C. , Wan Zhongxiao , Williams Deon B. , Stefanson Amanda L. , Wright David C.
Published: April 2012

Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a master regulator of mitochondrial biogenesis and is controlled, at least in part, through AMP-activated protein kinase and p38-dependent pathways. There is evidence demonstrating that activation of these kinases and induction of PGC-1α in skeletal muscle are regulated by catecholamines. The purpose of the present study was to determine if consumption of a high-fat diet (HFD) impairs epinephrine and 5-aminoimidazole-4-carboxamide-1β-d-ribofuranoside (AICAR) signaling and induction of PGC-1α in rat skeletal muscle. Male Wistar rats were fed chow or a HFD for 6 wk and then given a weight-adjusted bolus injection of epinephrine (20, 10, or 5 μg/100 g body wt sc) or saline, and triceps muscles were harvested 30 min (signaling) or 2 and 4 h (gene expression) postinjection. Despite blunted increases in p38 phosphorylation, the ability of epinephrine to induce PGC-1α was intact in skeletal muscle from HFD-fed rats and was associated with normal increases in activation of PKA and phosphorylation of cAMP response element-binding protein, reputed mediators of PGC-1α expression. The attenuated epinephrine-mediated increase in p38 phosphorylation was independent of increases in MAPK phosphatase 1. At 2 h following AICAR treatment (0.5 g/kg body wt sc), AMP-activated protein kinase and acetyl-CoA carboxylase phosphorylation were similar in skeletal muscle from chow- and HFD-fed rats. Surprisingly, AICAR-induced increases in PGC-1α mRNA levels were greater in skeletal muscle from HFD-fed rats. Our results demonstrate that the ability of epinephrine and AICAR to induce PGC-1α remains intact in skeletal muscle from HFD-fed rats. These results question the existence of reduced β-adrenergic responsiveness in diet-induced obesity and demonstrate that increases in p38 phosphorylation are not required for induction of PGC-1α in muscle from obese rats.
Ablation of sarcolipin results in atrial remodeling
Authors: Xie Lai-Hua , Shanmugam Mayilvahanan , Park Ji Yeon , Zhao Zhenghang , Wen Hairuo , Tian Bin , Periasamy Muthu , Babu Gopal J.
Published: April 2012

Sarcolipin (SLN) is a key regulator of sarco(endo)plasmic reticulum (SR) Ca2+-ATPase (SERCA), and its expression is altered in diseased atrial myocardium. To determine the precise role of SLN in atrial Ca2+ homeostasis, we developed a SLN knockout ( sln−/−) mouse model and demonstrated that ablation of SLN enhances atrial SERCA pump activity. The present study is designed to determine the long-term effects of enhanced SERCA activity on atrial remodeling in the sln−/− mice. Calcium transient measurements show an increase in atrial SR Ca2+ load and twitch Ca2+ transients. Patch-clamping experiments demonstrate activation of the forward mode of sodium/calcium exchanger, increased L-type Ca2+ channel activity, and prolongation of action potential duration at 90% repolarization in the atrial myocytes of sln−/− mice. Spontaneous Ca2+ waves, delayed afterdepolarization, and triggered activities are frequent in the atrial myocytes of sln−/− mice. Furthermore, loss of SLN in atria is associated with increased interstitial fibrosis and altered expression of genes encoding collagen and other extracellular matrix proteins. Our results also show that the sln−/− mice are susceptible to atrial arrhythmias upon aging. Together, these findings indicate that ablation of SLN results in increased SERCA activity and SR Ca2+ load, which, in turn, could cause abnormal intracellular Ca2+ handling and atrial remodeling.
Inhibition of bladder overactivity by a combination of tibial neuromodulation and tramadol treatment in cats
Authors: Zhang Fan , Mally Abhijith D. , Ogagan P. Dafe , Shen Bing , Wang Jicheng , Roppolo James R. , de Groat William C. , Tai Changfeng
Published: April 2012

Our recent study in cats revealed that inhibition of bladder overactivity by tibial nerve stimulation (TNS) depends on the activation of opioid receptors. TNS is a minimally invasive treatment for overactive bladder (OAB), but its efficacy is low. Tramadol (an opioid receptor agonist) is effective in treating OAB but elicits significant adverse effects. This study was to determine if a low dose of tramadol (expected to produce fewer adverse effects) can enhance the TNS inhibition of bladder overactivity. Bladder overactivity was induced in α-chloralose-anesthetized cats by an intravesical infusion of 0.25% acetic acid (AA) during repeated cystometrograms (CMGs). TNS (5 Hz) at two to four times the threshold intensity for inducing toe movement was applied during CMGs before and after tramadol (0.3–7 mg/kg iv) to examine the interaction between the two treatments. AA irritation significantly reduced bladder capacity to 24.8 ± 3.3% of the capacity measured during saline infusion. TNS alone reversibly inhibited bladder overactivity and significantly increased bladder capacity to 50–60% of the saline control capacity. Tramadol administered alone in low doses (0.3–1 mg/kg) did not significantly change bladder capacity, whereas larger doses (3–7 mg/kg) increased bladder capacity (50–60%). TNS in combination with tramadol (3–7 mg/kg) completely reversed the effect of AA. Tramadol also unmasked a prolonged (>2 h) TNS inhibition of bladder overactivity that persisted after termination of the stimulation. The results suggest a novel treatment strategy for OAB by combining tibial neuromodulation with a low dose of tramadol, which is minimally invasive with a potentially high efficacy and fewer adverse effects.
The function and molecular identity of inward rectifier channels in vestibular hair cells of the mouse inner ear
Authors: Levin Michaela E. , Holt Jeffrey R.
Published: April 2012

Inner ear hair cells respond to mechanical stimuli with graded receptor potentials. These graded responses are modulated by a host of voltage-dependent currents that flow across the basolateral membrane. Here, we examine the molecular identity and the function of a class of voltage-dependent ion channels that carries the potassium-selective inward rectifier current known as IK1. IK1has been identified in vestibular hair cells of various species, but its molecular composition and functional contributions remain obscure. We used quantitative RT-PCR to show that the inward rectifier gene, Kir2.1, is highly expressed in mouse utricle between embryonic day 15 and adulthood. We confirmed Kir2.1 protein expression in hair cells by immunolocalization. To examine the molecular composition of IK1, we recorded voltage-dependent currents from type II hair cells in response to 50-ms steps from −124 to −54 in 10-mV increments. Wild-type cells had rapidly activating inward currents with reversal potentials close to the K+equilibrium potential and a whole-cell conductance of 4.8 ± 1.5 nS ( n = 46). In utricle hair cells from Kir2.1-deficient (Kir2.1−/−) mice, IK1was absent at all stages examined. To identify the functional contribution of Kir2.1, we recorded membrane responses in current-clamp mode. Hair cells from Kir2.1−/−mice had significantly ( P < 0.001) more depolarized resting potentials and larger, slower membrane responses than those of wild-type cells. These data suggest that Kir2.1 is required for IK1in type II utricle hair cells and contributes to hyperpolarized resting potentials and fast, small amplitude receptor potentials in response to current inputs, such as those evoked by hair bundle deflections.
Effects of repeated walking in a perturbing environment: a 4-day locomotor learning study
Authors: Blanchette Andreanne , Moffet Helene , Roy Jean-Sébastien , Bouyer Laurent J.
Published: April 2012

Previous studies have shown that when subjects repeatedly walk in a perturbing environment, initial movement error becomes smaller, suggesting that retention of the adapted locomotor program occurred (learning). It has been proposed that the newly learned locomotor program may be stored separately from the baseline program. However, how locomotor performance evolves with repeated sessions of walking with the perturbation is not yet known. To address this question, 10 healthy subjects walked on a treadmill on 4 consecutive days. Each day, locomotor performance was measured using kinematics and surface electromyography (EMGs), before, during, and after exposure to a perturbation, produced by an elastic tubing that pulled the foot forward and up during swing, inducing a foot velocity error in the first strides. Initial movement error decreased significantly between days 1 and 2 and then remained stable. Associated changes in medial hamstring EMG activity stabilized only on day 3, however. Aftereffects were present after perturbation removal, suggesting that daily adaptation involved central command recalibration of the baseline program. Aftereffects gradually decreased across days but were still visible on day 4. Separation between the newly learned and baseline programs may take longer than suggested by the daily improvement in initial performance in the perturbing environment or may never be complete. These results therefore suggest that reaching optimal performance in a perturbing environment should not be used as the main indicator of a completed learning process, as central reorganization of the motor commands continues days after initial performance has stabilized.
Characterization of the interactions of β‒amyloid peptides with glycolipid receptors by surface plasmon resonance
Authors: Valdes-Gonzalez Tania , Inagawa Junichi , Ido Tatsuo
Published: April 2012

Interactions between β‒amyloid (Aβ) peptides and neuronal membranes play an important role in Alzheimer′s disease (AD). Using surface plasmon resonance we assayed a kinetic model to study the interactions of Aβ25‒35, Aβ40 and Aβ42 with surfaces containing single glycolipids (Asialo‒GM1, GM1, GD1a or GT1b). The larger peptides interacted with gangliosides stronger than Aβ25‒35, which showed some significant bindings solely at high concentrations under acidic conditions. Only the interactions at low Aβ concentrations were useful to calculate the kinetic constants. The affinities increased at low pH. The specificity, but not the affinity correlated with the number of sialic acids in the ganglioside sugar moiety. The most important finding in this study, was a special group of sensorgrams with linear association phases that appeared for the interactions of Aβ with the membranes containing gangliosides, due to the following process: when Aβ is injected at a critical concentration, the first molecules that interact with the gangliosides remain fixed on the membrane. Next Aβ molecules bind to these fixed molecules, so that for each Aβ molecule bound, new binding sites are activated on the surface in a linear ratio, which explains the linear shape of the sensorgrams. This way a laminar‒arranged Aβ accumulate is progressively formed on the membrane surface and fixed there. These linear sensorgrams were not observe with asialo‒GM1 or DMPC, which indicates the main role of sialic acid in these interactions. This model for progressive Aβ deposition could simulate the initial stage of the Aβ peptide accumulation on cell surfaces.
New chaetoglobosins from maize infested by Phomopsis leptostromiformis fungi. Production, identification, and semi‒synthesis
Authors: Burlot Ludovic , Cherton Jean-Claude , Convert Odile , Correia Isabelle , Dennetiere Bruno
Published: April 2012

This paper deals with the cytotoxic chaetoglobosins obtained from culture on maize of the strains ATCC 26115 and MRC 2654 of the fungus Phomopsis leptostromiformis Both strains produced, in more or less important amounts, the known chaetoglobosins M (1) and N (2). In addition, the new chaetoglobosin O (3), was isolated from the ATCC 26115 strain and characterized by HRMS and 2D NMR experiments. With the MRC 2654 strain, a fungal metabolite 4, more polar than the chaetoglobosins M and N, was extracted and purified. Spectroscopic and chromatographic data of metabolite 4 led to its identification to the bridged chaetoglobosin named compound S, which previously has been obtained by intramolecular Michael reaction on the chaetoglobosin M. Moreover, a methylation under Williamson conditions of the chaetoglobosin 4 resulted in the formation of the trimethylated chaetoglobosin 5.
Microwave Synthesis, Spectral, Thermal and Antimicrobial Studies of Some Co(II), Ni(II) and Cu(II) Complexes Containing 2‐Aminothiazole Moiety
Authors: Mishra A. P. , Purwar H. , Jain Rajendra K. , Gupta S. K.
Published: April 2012

Some new Schiff base metal complexes of Co(II), Ni(II) and Cu(II) derived from 4‐chlorobenzylidene‐2‐aminothiazole (CAT) and 2‐nitrobenzylidene‐2‐aminothiazole (NAT) have been synthesized by conventional as well as microwave methods. These compounds have been characterized by elemental analysis, FT‐IR, FAB‐mass, molar conductance, electronic spectra, ESR, magnetic susceptibility, thermal, electrical conductivity and XRD analysis. The complexes are coloured and stable in air. Analytical data revealed that all the complexes exhibited 1:2 (metal:ligand) ratio with coordination number 4 or 6. FAB‐mass and thermal data show degradation pattern of the complexes. The thermal behavior of metal complexes shows that the hydrated complexes loses water molecules of hydration in the first step; followed by decomposition of ligand molecules in the subsequent steps. The crystal system, lattice parameter, unit cell volume and number of molecules in unit cell in the lattice of complexes have been determined by XRD analysis. XRD patterns indicate crystalline nature for the complexes. The solid state electrical conductivity of the metal complexes has also been measured. Solid state electrical conductivity studies reflect semiconducting nature of the complexes. The Schiff base and metal complexes show a good activity against the Gram‐positive bacteria; Staphylococcus aureus and Gram‐negative bacteria; Escherichia coli and fungi Aspergillus niger and Candida albicans.
Dysphagia due to Diffuse Idiopathic Skeletal Hyperostosis
Authors: Ohki Masafumi
Published: April 2012

Diffuse idiopathic skeletal hyperostosis (DISH) is usually asymptomatic. However, rarely, it causes dysphagia, hoarseness, dyspnea, snoring, stridor, and laryngeal edema. Herein, we present a patient with DISH causing dysphagia. A 70-year-old man presented with a 4-month history of sore throat, dysphagia, and foreign body sensation. Flexible laryngoscopy revealed a leftward-protruding posterior wall in the hypopharynx. Computed tomography and magnetic resonance imaging revealed a bony mass pushing, anteriorly, on the posterior hypopharyngeal wall. Ossification included an osseous bridge involving 5 contiguous vertebral bodies. Dysphagia due to DISH was diagnosed. His symptoms were relieved by conservative therapy using anti-inflammatory drugs. However, if conservative therapy fails and symptoms are severe, surgical treatments must be considered.
Implementation of Ring-Oscillators-Based Physical Unclonable Functions with Independent Bits in the Response
Authors: Bernard Florent , Fischer Viktor , Costea Crina , Fouquet Robert
Published: April 2012

The paper analyzes and proposes some enhancements of Ring-Oscillators-based Physical Unclonable Functions (PUFs). PUFs are used to extract a unique signature of an integrated circuit in order to authenticate a device and/or to generate a key. We show that designers of RO PUFs implemented in FPGAs need a precise control of placement and routing and an appropriate selection of ROs pairs to get independent bits in the PUF response. We provide a method to identify which comparisons are suitable when selecting pairs of ROs. Dealing with power consumption, we propose a simple improvement that reduces the consumption of the PUF published by Suh et al. in 2007 by up to 96.6%. Last but not least, we point out that ring oscillators significantly influence one another and can even be locked. This questions the reliability of the PUF and should be taken into account during the design.
Clinical Perspectives of Urocortin and Related Agents for the Treatment of Cardiovascular Disease
Authors: Ikeda Keiichi , Fujioka Kouki , Manome Yoshinobu , Tojo Katsuyoshi
Published: April 2012

The effects of corticotropin-releasing hormone, also known as corticotropin-releasing factor (CRF), on the cardiovascular system have been intensively researched since its discovery. Moreover, the actions of urocortin (Ucn) I on the cardiovascular system have also been intensively scrutinized following the cloning and identification of its receptor, CRF receptor type 2 (CRFR2), in peripheral tissues including the heart. Given the cardioprotective actions of CRFR2 ligands, the clinical potential of not only Ucn I but also Ucn II and III, which were later identified as more specific ligands for CRFR2, has received considerable attention from researchers. In addition, recent work has indicated that CRF type 1 receptor may be also involved in cardioprotection against ischemic/reperfusion injury. Here we provide a historical overview of research on Ucn I and related agents, their effects on the cardiovascular system, and the clinical potential of the use of such agents to treat cardiovascular diseases.
Reactive Oxygen Species and Nitric Oxide in Cutaneous Leishmaniasis
Authors: Horta Maria Fátima , Mendes Bárbara Pinheiro , Roma Eric Henrique , Noronha Fátima Soares Motta , Macêdo Juan Pereira , Oliveira Luciana Souza , Duarte Myrian Morato , Vieira Leda Quercia
Published: April 2012

Cutaneous leishmaniasis affects millions of people around the world. Several species ofLeishmaniainfect mouse strains, and murine models closely reproduce the cutaneous lesions caused by the parasite in humans. Mouse models have enabled studies on the pathogenesis and effector mechanisms of host resistance to infection. Here, we review the role of nitric oxide (NO), reactive oxygen species (ROS), and peroxynitrite (ONOO−) in the control of parasites by macrophages, which are both the host cells and the effector cells. We also discuss the role of neutrophil-derived oxygen and nitrogen reactive species during infection withLeishmania. We emphasize the role of these cells in the outcome of leishmaniasis early after infection, before the adaptive Th-cell immune response.
Guidance Stabilization of Satellites Using the Geomagnetic Field
Authors: Miranda Francisco
Published: April 2012

In the last years the small satellites have played an important role in the technological development. The attractive short period of design and low cost of them and the capacity to solve problems that are usually considered as problems to big and expensive spacecrafts lead us to study the control problem of these satellites. Active three-axis magnetic attitude stabilization of a low Earth orbit satellite is considered in this work. The control is created by interaction between the magnetic moment generated by magnetorquers mounted on the satellite body and the geomagnetic field. This problem is quite complex and difficult to solve. To overcome this difficulty guidance control is considered, where we use ε-strategies introduced by Pontryagin in the frame of differential games theory. Qualitative analysis and results of numerical simulation are presented.
Synthesis and Anticancer Activity of Some New Derivatives of Coumarin and Quinolinyl Mercaptotriazoles
Authors: Hosny Mona A. , Radwan Hyam A. , El-Sawi Emtithal A.
Published: April 2012

Pechmann condensation of ethylacetoacetate with derivatives of phenol by heating in absence of solvent and with montmorillonite clays K‐10 afforded coumarin derivatives (1a-e) in good yields which on reaction with thiosemicarbazide in anhydrous pyridine yielded coumarin‐quinolinyl mercaptotriazole (2a-e). The latter compounds were evaluated for their antimicrobial and anticancer activities. The newly synthesized compounds were characterized by IR, 1HNMR and mass spectra.
Synergistic and Antagonistic Effects of Sodium Molybdate‐Zn2+ System
Authors: Sahayaraj J. Wilson , Amalraj A. John , Rajendran Susai , Vijaya N.
Published: April 2012

The inhibition efficiency (IE) of sodium molybdate (SM) in controlling corrosion of carbon steel in an aqueous solution containing 120 ppm of Cl-, in the absence and presence of Zn2+ has been evaluated by weight‐loss method. A synergistic effect exists between SM and Zn2+ when the concentration of Zn2+ is 25 ppm and above. Inhibition efficiencies obtained are greater than 85%. Antagonistic effect exists between SM and Zn2+ when the concentration of Zn2+ is 10 ppm and below. The SM‐Zn2+ system shows excellent IE up to third day. Above third day IE decreases. Acceleration of corrosion takes place. Excellent IE is shown at pH 5,7 and 12. At pH 9, IE decreases since Zn2+ is precipitated as Zn(OH)2 in the bulk of the solution. Polarization study reveals that SM‐Zn2+ system functions as a mixed inhibitor. FTIR spectra reveal that the protective film consists of Fe2+‐SM complex and Zn(OH)2.
Development, Validation and Statistical Correlation of RP–LC Methods for Determination of Atazanavir Sulfate in Capsule Dosage Form
Authors: Behera A. , Sankar D. G. , Moitra S. K. , Si S. C.
Published: April 2012

To study the effective therapeutic bioavailability of Atazanavir Sulfate (ATV), administered singly or in combination with Ritonavir, a cost effective and rapid method is required. In order to assess an in‐depth study, it is primarily thought prudent to develop an effective analytical method for estimation of ATV in marketed dosage forms. The present work is to develop a simple and precise analytical method for in depth evaluation of therapeutic efficacy of ATV. The novelty of the method shows linearity in the concentration range of 10‐100 µg/mL at two wavelengths, i.e. 254 nm and 284 nm respectively. The chromatographic system consists of HiQSil C18HS column; an isocratic mobile phase consisted of methanol and tetrahydrofuran (95:5 v/v). The developed method is validated according to ICH guidelines in capsule dosage form. Validation of the developed method shows good result in range, linearity, accuracy and precision. Student’s t–test was used to correlate the two methods and applied to raw materials and capsule dosage form.
Analysis and Interpretation of the Field and Laboratory Geophysical Measurements of Black-Sand Beach Deposits, East Rosetta, Egypt
Authors: El-Sadek Mohamed A. , Ammar Ahmed A. , Elkhateeb Sayed A.
Published: April 2012

The present study deals with the analysis and interpretation of the results of field geophysical survey and laboratory geophysical measurements. The study of the magnetic and electrical methods was selected because the beach sands contain many minerals that have magnetic and electric properties. Analysis and interpretation of the field and laboratory magnetic and geoelectric maps demonstrated that the investigated beach-alluvial deposits can be subdivided according to their magnetic and geoelectric properties into three main zones striking nearly parallel to the shoreline of the Mediterranean Sea at the study area. The northern zone is more enriched in black sands than the central or southern zones. Field and laboratory magnetic susceptibility measurements provided very useful maps for the concentration of heavy minerals. The deep-seated magnetic response was calculated at an average depth of 239.6 m, while the near-surface magnetic responses were computed at average depths of 9.1, 57.9, and 81.8 m, respectively. The correlation between the geophysical features, recorded on the total magnetic field intensity, the electric resistivity, the IP chargeability, and the calculated metal factor, was found to agree to a great extent. The heavymineral concentration was found to decrease with depth. However, the heavyminerals show parallel zones below the surface, suggesting similar sedimentation environments.
Synthesis, Anti‐Bacterial and Anti‐Fungal Evaluation of Pyrazoline Derivatives
Authors: Panchal Ashvin D. , Patel Pravinkumar M.
Published: April 2012

The Series of N‐(5‐(Substituted phenyl)‐4,5‐dihydro‐1H‐pyrazol‐3‐yl)‐4H‐1,2,4‐triazol‐4‐amine compounds were prepared by reaction of 4‐amino‐1,2,4‐Triazole with Acetyl Chloride followed by different aromatic aldehydes and cyclization with hydrazine hydrate. The structures of new compounds were confirmed by IR and 1H‐NMR spectral data. Anti‐bacterial and Anti‐fungal activities were evaluated and compared with the standard drugs, some compounds of the series exhibited promising anti‐microbial and anti‐fungal activity compared to standard drugs.
Limb-Shaking Transient Ischemic Attacks Successfully Treated with External Carotid Artery Stenting
Authors: Kouvelos George N. , Nassis Christos , Papa Nektario , Papadopoulos George , Matsagkas Miltiadis I.
Published: April 2012

The external carotid artery (ECA) is one of the most important extracranial-to-intracranial sources of collateral circulation, contributing significantly to the cerebral blood flow especially when perfusion through the internal carotid artery (ICA) is compromised. Most of the endovascular studies so far have been dedicated to ICA, with little focus on the ECA. Limb-shaking transient ischemic attacks (TIAs) are a relatively rare manifestation of carotid artery disease that may present with repetitive shaking movements of the affected limbs. We report a case of an 80-year-old male with bilateral internal and contralateral external carotid artery occlusion who developed limb-shaking TIAs as a result of significant stenosis of the right ECA. Percutaneous revascularization of the ECA was performed by angioplasty and stenting. At the follow-up 12 months later, the patient remained neurologically intact with complete resolution of his symptoms. Stenting of the ECA should be considered as a reasonable alternative to conventional open repair especially in patients with contralateral carotid stenosis, insufficient circle of Willis, and significant comorbidities.
Solvent‐Free Synthesis of 1,8‐Dioxo‐octahydroxanthenes and 14‐Aryl‐14H‐dibenzo[a,j]xanthenes using Saccharin SulfonicAcid as an Efficient and Green Catalyst
Authors: Zare Abdolkarim , Mokhlesi Mohammad , Hasaninejad Alireza , Hekmat-Zadeh Tahereh
Published: April 2012

Saccharin sulfonic acid (SaSA) is utilized as a highly efficient, green and inexpensive sulfonic acid‐containing catalyst for the following one‐pot multi‐component organic transformations: (i) the condensation of dimedone (2 eq.) with aromatic aldehydes (1 eq.) leading to 1,8‐dioxo‐octahydroxanthenes, and (ii) the reaction of 2‐naphthol (2 eq.) with arylaldehydes (1 eq.) leading to 14‐aryl‐14H‐dibenzo[a,j]xanthenes. In these protocols, the title compounds are produced in high to excellent yields and in relatively short reaction times under solvent‐free conditions.
Investigation of Friedel‐Crafts Alkylation in the Presence of Supported Sulfonic Acid on Silica Gel
Authors: Kiasat A. R. , Karimi-Cheshmeali M. , Soleymani R. , Rajabzadeh H.
Published: April 2012

From the Reaction between cellulose and chloro sulfonic acid was prepared sulfuric acid cellulose composition as a new solid acid. The solid acid supported on silica gel and then as an effective catalyst in Friedel‐Crafts alkylation of alcohols and aromatic compounds was used. The reaction progress was controlled using thin layer chromatography and the reaction products were analyzed using IR spectroscopy devise. The results show this new catalyst is effective in the friedel crafts alkylation and C‐C bond formation was done in short time with very good yields.
Neuropathology of Temporal Lobe Epilepsy
Authors: Al Sufiani Fahd , Ang Lee Cyn
Published: April 2012

Pathologic findings in surgical resections from patients with temporal lobe epilepsy include a wide range of diagnostic possibilities that can be categorized into different groups on the basis of etiology. This paper outlines the various pathologic entities described in temporal lobe epilepsy, including some newly recognized epilepsy-associated tumors, and briefly touch on the recent classification of focal cortical dysplasia. This classification takes into account coexistent pathologic lesions in focal cortical dysplasia.
p53 Family: Role of Protein Isoforms in Human Cancer
Authors: Wei Jinxiong , Zaika Elena , Zaika Alexander
Published: April 2012

TP53,TP63, andTP73genes comprise the p53 family. Each gene produces protein isoforms through multiple mechanisms including extensive alternative mRNA splicing. Accumulating evidence shows that these isoforms play a critical role in the regulation of many biological processes in normal cells. Their abnormal expression contributes to tumorigenesis and has a profound effect on tumor response to curative therapy. This paper is an overview of isoform diversity in the p53 family and its role in cancer.
Advances in Corticosteroid Therapy for Ocular Inflammation: Loteprednol Etabonate
Authors: Comstock Timothy L. , DeCory Heleen H.
Published: April 2012

Topical corticosteroids are effective in reducing anterior segment inflammation but are associated with adverse drug reactions (ADRs) including elevation of intraocular pressure (IOP) and cataract formation. Retrometabolic drug design has advanced the development of new corticosteroids with improved therapeutic indices. Engineered from prednisolone, loteprednol etabonate (LE) has a 17α-chloromethyl ester, in lieu of a ketone group, and a 17β-etabonate group. LE is highly lipophilic and binds with high affinity to the glucocorticoid receptor; any unbound LE is metabolized to inactive metabolites. LE has been studied in several anterior segment inflammatory conditions (giant papillary conjunctivitis, allergic conjunctivitis, anterior uveitis, and keratoconjunctivitis sicca), and in postoperative ocular inflammation and pain. Combined with tobramycin, it is effective in blepharokeratoconjunctivitis. Elevations in IOP are infrequent with LE, and the absence of a C-20 ketone precludes formation of Schiff base intermediates with lens proteins, a common first step implicated in cataract formation with ketone steroids.
Study Structure and Properties of Nanocomposite Material Based on Unsaturated Polyester with Clay Modified by Poly(ethylene oxide)
Authors: Duy Thanh Tran , Dang Mao Nguyen , Kim Ngan Nguyen Thi , Chi Nhan Ha Thuc , Huy Ha Thuc , Grillet Anne-Cecile
Published: April 2012

In recent years, polymer clay nanocomposites have been attracting considerable interests in polymers science because of their advantages. There are many scientists who researched about this kind of material and demonstrated that when polymer matrix was added to little weight of clay, properties were enhanced considerably. Because clay is a hydrophilic substance so it is difficult to use as filler in polymer matrix having hydrophobic nature, so clay needs to be modified to become compatible with polymer. In this study, poly(ethylene oxide) was used as a new modifier for clay to replace some traditional ionic surfactants such as primary, secondary, tertiary, and quaternary alkyl ammonium or alkylphosphonium cations having the following disadvantages: disintegrate at high temperature, catalyze polymer degradation, and make nanoproducts colorific, and so forth. In order to evaluate modifying effect of poly(ethylene oxide), modified clay products were characterize d by X‐ray spectrum. Then organoclay was used to prepare nanocomposite based on unsaturated polyester. Morphology and properties of nanocomposites were measure d by X‐ray diffraction, transmission electron microscopy, tensile strength, and thermal stability. The results showed that clay galleries changed to intercalated state in the nanocomposites. Properties of nanocomposites were improved a lot when the loading of the organoclay was used at 1 phr.
Solution and Hyers‐Ulam‐Rassias Stability ofGeneralized Mixed Type Additive‐QuadraticFunctional Equations in Fuzzy Banach Spaces
Authors: Eshaghi Gordji M. , Azadi Kenary H. , Rezaei H. , Lee Y. W. , Kim G. H.
Published: April 2012

By using fixed point methods and direct method, we establish the
generalized Hyers‐Ulam stability of the following additive‐quadratic functional equation f(x + ky) + f(x − ky) = f(x + y) + f(x − y)+(2(k + 1)/k)f(ky) − 2(k + 1)f(y) for fixed integers k with k ≠ 0, ±1 in fuzzy Banach spaces.
Phase II Study of Single-Agent Navitoclax (ABT-263) and Biomarker Correlates in Patients with Relapsed Small Cell Lung Cancer
Authors: Rudin Charles M. , Hann Christine L. , Garon Edward B. , Ribeiro de Oliveira Moacyr , Bonomi Philip D. , Camidge D. Ross , Chu Quincy , Giaccone Giuseppe , Khaira Divis , Ramalingam Suresh S. , Ranson Malcolm R. , Dive Caroline , McKeegan Evelyn M. , Chyla Brenda J. , Dowell Barry L. , Chakravartty Arunava , Nolan Cathy E. , Rudersdorf Niki , Busman Todd A. , Mabry Mack H. , Krivoshik Andrew P. , Humerickhouse Rod A. , Shapiro Geoffrey I. , Gandhi Leena
Published: April 2012

Purpose: Bcl-2 is a critical regulator of apoptosis that is overexpressed in the majority of small cell lung cancers (SCLC). Nativoclax (ABT-263) is a potent and selective inhibitor of Bcl-2 and Bcl-xL. The primary objectives of this phase IIa study included safety at the recommended phase II dose and preliminary, exploratory efficacy assessment in patients with recurrent and progressive SCLC after at least one prior therapy.

Experimental Design: Thirty-nine patients received navitoclax 325 mg daily, following an initial lead-in of 150 mg daily for 7 days. Study endpoints included safety and toxicity assessment, response rate, progression-free and overall survival (PFS and OS), as well as exploratory pharmacodynamic correlates.

Results: The most common toxicity associated with navitoclax was thrombocytopenia, which reached grade III–IV in 41% of patients. Partial response was observed in one (2.6%) patient and stable disease in 9 (23%) patients. Median PFS was 1.5 months and median OS was 3.2 months. A strong association between plasma pro–gastrin-releasing peptide (pro-GRP) level and tumor Bcl-2 copy number (R = 0.93) was confirmed. Exploratory analyses revealed baseline levels of cytokeratin 19 fragment antigen 21-1, neuron-specific enolase, pro-GRP, and circulating tumor cell number as correlates of clinical benefit.

Conclusion: Bcl-2 targeting by navitoclax shows limited single-agent activity against advanced and recurrent SCLC. Correlative analyses suggest several putative biomarkers of clinical benefit. Preclinical models support that navitoclax may enhance sensitivity of SCLC and other solid tumors to standard cytotoxics. Future studies will focus on combination therapies. Clin Cancer Res; 18(11); 3163–9. ©2012 AACR.
Dibenzophenanthridines as Inhibitors of Glutaminase C and Cancer Cell Proliferation
Authors: Katt William P. , Ramachandran Sekar , Erickson Jon W. , Cerione Richard A.
Published: April 2012

One hallmark of cancer cells is their adaptation to rely upon an altered metabolic scheme that includes changes in the glycolytic pathway, known as the Warburg effect, and elevated glutamine metabolism. Glutaminase, a mitochondrial enzyme, plays a key role in the metabolism of glutamine in cancer cells, and its inhibition could significantly impact malignant transformation. The small molecule 968, a dibenzophenanthridine, was recently shown to inhibit recombinantly expressed glutaminase C, to block the proliferation and anchorage-independent colony formation of human cancer cells in culture, and to inhibit tumor formation in mouse xenograft models. Here, we examine the structure–activity relationship that leads to 968-based inhibition of glutaminase and cancer cell proliferation, focusing upon a “hot-spot” ring previously identified as critical to 968 activity. We find that the hot-spot ring must be substituted with a large, nonplanar functionality (e.g., a t-butyl group) to bestow activity to the series, leading us to a model whereby the molecule binds glutaminase at a previously undescribed allosteric site. We conduct docking studies to locate potential 968-binding sites and proceed to test a specific set of docking solutions via site-directed mutagenesis. We verify the results from our initial assay of 968 and its analogues by cellular studies using MDA-MB-231 breast cancer cells. Mol Cancer Ther; 11(6); 1269–78. ©2012 AACR.
Contribution of Impaired Mitochondrial Autophagy to Cardiac Aging
Authors: Dutta Debapriya , Calvani Riccardo , Bernabei Roberto , Leeuwenburgh Christiaan , Marzetti Emanuele
Published: April 2012

The prevalence of cardiovascular disease increases with advancing age. Although long-term exposure to cardiovascular risk factors plays a major role in the etiopathogenesis of cardiovascular disease, intrinsic cardiac aging enhances the susceptibility to developing heart pathologies in late life. The progressive decline of cardiomyocyte mitochondrial function is considered a major mechanism underlying heart senescence. Damaged mitochondria not only produce less ATP but also generate increased amounts of reactive oxygen species and display a greater propensity to trigger apoptosis. Given the postmitotic nature of cardiomyocytes, the efficient removal of dysfunctional mitochondria is critical for the maintenance of cell homeostasis, because damaged organelles cannot be diluted by cell proliferation. The only known mechanism whereby mitochondria are turned over is through macroautophagy. The efficiency of this process declines with advancing age, which may play a critical role in heart senescence and age-related cardiovascular disease. The present review illustrates the putative mechanisms whereby alterations in the autophagic removal of damaged mitochondria intervene in the process of cardiac aging and in the pathogenesis of specific heart diseases that are especially prevalent in late life (eg, left ventricular hypertrophy, ischemic heart disease, heart failure, and diabetic cardiomyopathy). Interventions proposed to counteract cardiac aging through improvements in macroautophagy (eg, calorie restriction and calorie restriction mimetics) are also presented.
Growth Factors, Nutrient Signaling, and Cardiovascular Aging
Authors: Fontana Luigi , Vinciguerra Manlio , Longo Valter D.
Published: April 2012

Growth factors regulated by specific macronutrients have been shown to promote aging and accelerate mortality in the majority of the organisms studied. In particular, the enzymes activated by growth hormone, insulin, and insulin-like growth factor-1 in mammals and their orthologs in simple model organisms represent perhaps the best-understood proteins involved in the aging process. Dietary restriction, which reduces the level of insulin-like growth factor-1 and of other growth factors, has been associated with protection from diabetes, cancer, and cardiovascular diseases, and deficiencies in growth hormone signaling and insulin-like growth factor-1 are strongly associated with protection from cancer and diabetes in both mice and humans; however, their role in cardiac function and cardiovascular diseases is controversial. Here, we review the link between growth factors, cardiac function, and heart disease with focus on the cardioprotective and sensitizing effect of growth factors in both model organisms and humans.
An Investigation into the Spatial Variability of Near-Surface Air Temperatures in the Detroit, Michigan, Metropolitan Region
Authors: Oswald Evan M. , Rood Richard B. , Zhang Kai , Gronlund Carina J. , O’Neill Marie S. , White-Newsome Jalonne L. , Brines Shannon J. , Brown Daniel G.
Published: April 2012

On an annual basis, heat is the chief cause of weather-related deaths in the United States. Therefore, understanding the temperature structure where people live is important for reducing the health burden imposed by hot weather. This study focused on the air temperatures in the Detroit, Michigan, metropolitan region during the summer of 2009. An observational network was established that included 1) monitors sited in the backyards of residential participants, 2) National Weather Service standard observations, and 3) a network of monitors operated by the State of Michigan. Daily high and low temperatures were analyzed for spatial pattern, magnitude of spatial variability, and relationships with weather conditions. The existence of spatial variability was confirmed specifically during weather that was considered to be dangerous to public health. The relationships between temperature observations and distance to water, distance to city center, and local percent of impervious surface were investigated. The spatial variability during the daily low was typically stronger in magnitude and the spatial pattern was more consistent than were those during the daily high. The largest correlation with land-cover and location attributes was between values of percent of impervious surface and daily low temperatures. Daily high temperatures were most correlated with distance to water. Consistent with previous studies on spatial variability in urban environments, the results suggest a need for sensitivity to the spatially variable nature of exposure to heat events in both public health and urban planning. For example, these results showed that the downtown area experienced elevated temperatures during nights and that the eastern portions of Detroit experienced decreased temperatures during afternoons.
Seasonal Variation of Surface Temperature–Modulating Factors in the Sonoran Desert in Northwestern Mexico
Authors: Tereshchenko Iryna , Zolotokrylin Alexander N. , Titkova Tatiana B. , Brito-Castillo Luis , Monzon Cesar Octavio
Published: April 2012

The authors explore a new approach to monitoring of desertification that is based on use of results on the relation between albedo and surface temperature for the Sonoran Desert in northwestern Mexico. The criteria of predominance of radiation by using the threshold value of Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS) normalized difference vegetation index (NDVI) were determined. The radiation mechanism for regulating the temperature of the surface and the definition of threshold values for AVHRR and MODIS NDVI have an objective justification for the energy budget, which is based on the dominance of radiation surface temperature regulation in relation to evapotranspiration. Changes in the extent of arid regions with AVHRR NDVI of <0.08 and MODIS NDVI of <0.10 can be considered to be a characteristic in the evolution of desertification in the Sonoran Desert region. This is true because, in a certain year, the time span of the period when radiation factor predominates is important for the desertification process.