bluuebunny/crossref_metadata_2025 huggingface dataset:
The acute cardiac electrophysiological effects of intravenous sotalol hydrochloride
Authors: Ward D. E. , Camm A. J. , Spurrell R. A. J.
Published: October 2013

The cardiac electrophysiological effects of sotalol were studied in ten patients (pts) aged 20‐65 years undergoing intracardiac stimulation studies for palpitations (7 pts) or dizzy spells (3 pts). The following measurements were made: 1. basic sinus cycle length (SCL); 2. sinus node recovery time (SNRT) following overdrive pacing; 3. intra‐atrial (PA), atrio‐His (AH) and His‐ventricular (HV) conduction intervals during regular atrial pacing; 4. effective refractory periods of the atria (AERP), AV node (AVERP) and ventricular myocardium (VERP). AV nodal functional refractoriness (AVFRP) was also determined. All measurements were repeated 10‐15 min after i.v. administration of 0.4 mg/kg of sotalol. Results were analysed by the Wilcoxon Signed Rank test. Significant increases in SCL (p < 0.01), AH (p < 0.01), SNRT (p < 0.01), AVERP (p < 0.02) and AVFRP (p < 0.01) were observed. These effects are consistent with the beta‐blocking action of sotalol. The acute increase in AERP (p < 0.01) is, however, not a common property of other betablockers and may be related to the ‘class III’ cellular effect of sotalol. These results are discussed in relationship to the electrophysiological effects of other beta‐blocking drugs.
Noninvasive assessment of cardiac motion: Comparison of the apexcardiogram and cardiokymogram
Authors: Hendel J. , Apstein C. S. , Jabbour S. , Vokonas P. S. , Hood W. B.
Published: October 2013

The apexcardiogram (ACG) and cardiokymogram (CKG) (displacement cardiogram) tracings were compared in 45 patients with a variety of cardiac diseases and in 16 normal subjects. The ACG and CKG were generally comparable in waveform and timing of standard tracing intervals; however, on a case by case comparison frequent discrepancies between the ACG and CKG were observed. In 13 patients where no ACG could be recorded, an interpretable CKG tracing was obtained. However, the CKG produced frequent artifacts, mirror images, was very sensitive to probe position, and was judged to be of limited advantage over the ACG.
Acute myocardial infarction: Intracoronary application of nitroglycerin and streptokinase
Authors: Rentrop K. P. , Blanke H. , Karsch K. R. , Wiegand V. , Köstering H. , Oster H. , Leitz K.
Published: October 2013

In five patients with acute myocardial infarction, the effects of both intracoronary nitroglycerin (NTG) and subsequent intracoronary streptokinase application were evaluated. In addition, transluminal recanalization was performed in one of these patients. Injection of NTG into the infarct‐related coronary artery resulted in improved distal filling of the subtotally occluded left circumflex artery in one patient, and in transient patency of the completely occluded right coronary artery in a second patient. In a third patient patency of the totally occluded left anterior descending artery (LAD) was achieved by transluminal recanalization with a guide wire. In a fourth patient with occlusion of the LAD, there was no response to intracoronary NTG and mechanical recanalization was not attempted. Subsequent intracoronary infusion of streptokinase (1,000‐2,000 U/min for 15‐60 min) resulted in a further and long‐term reduction of narrowing at the site of acute occlusion in patients I—III and in opening of the completely occluded LAD in patient IV. Improvement of lumen was paralleled by alleviation of symptoms. In a fifth patient, in whom the LAD was subtotally occluded, the degree of coronary obstruction could not be changed by intracoronary application of NTG or by lysis. In this patient, symptoms and ECG changes improved with reduction of pathologically elevated blood pressure values. The findings suggest that myocardial infarction had been caused by thrombotic occlusion in four patients, and that spasm of the infarct vessel could have been an additional factor in two of these patients. In the fifth patient, an increase of afterload in the presence of a subtotal lesion might have caused the critical imbalance between oxygen supply and demand, resulting in cell death.
Isolated chronic tricuspid insufficiency due to closed chest trauma: Report of a case with long‐term follow‐up
Authors: Vijayanagar R. , Bognolo D. A. , Harrison E. , Raju B. M. , Eckstein P. F. , Sbar S.
Published: October 2013

A case of isolated chronic tricuspid insufficiency due to closed chest trauma is described in this report. Studies for carcinoid syndrome were negative. At surgery the posterior leaflet of the tricuspid valve appeared to be torn and disrupted. The other leaflets were shortened and atrophic. The results of pre‐ and postoperative cardiac catheterization with long‐term follow‐up to the present, and the available literature on this rare entity has been briefly reviewed.
Hemoptysis, recurrent cerebrovascular accident, and emergency mitral valve replacement
Authors: Sambasivan V. , Edmiston W. A. , Veluz C. , Mendez M. A.
Published: October 2013

Hemoptysis in mitral stenosis may occur frequently, but massive pulmonary hemorrhage is uncommon. We describe a patient with mitral stenosis who had severe hemoptysis and required anticoagulation for recurrent embolic cerebrovascular accidents. The patient underwent successful mitral valve replacement with a Hancock bioprosthesis. There was no evidence of pulmonary bleeding following operation. This case illustrated that mitral valve operation may be performed in acutely ill patients for the relief of hemoptysis.
Usefulness and limitations of myocardial oxygen consumption indices
Authors: Baller D. , Zipfel J. , Hellige G.
Published: October 2013

Indirect indices of myocardial oxygen consumption (MV̇O2) are frequently applied to humans, both in health and disease, to estimate the energetic state of the myocardium. Despite widespread use, the validity of the previously reported oxygen consumption parameters has not yet been proven. Therefore, we designed experiments to examine any indices under maximal variations of hemodynamics and oxygen consumption with special reference to clinically applicable indices.
Effective use of captopril in postoperative paradoxical hypertension of coarctation of the aorta
Authors: Casta A. , Conti V. R. , Talabi A. , Brouhard B. H.
Published: October 2013

Severe systemic hypertension may complicate the postoperative course of patients undergoing surgical repair for coarctation of the aorta. The sympathetic and the renin‐angiotensin systems have been demonstrated as underlying mechanisms for this paradoxical phenomenon (Farrell et al., 1979; Rocchini et al., 1979). We recently utilized captopril, a competitive inhibitor of angiotensin converting enzyme, with success in the management of severe hypertension that developed in a 15‐year‐old male after successful surgical repair for coarctation of the aorta. To our knowledge, this is the first report on the use of captopril for the treatment of this paradoxical phenomenon.
The clinical diagnosis of nonanginal chest pain: The differentiation of angina from nonanginal chest pain by history
Authors: Constant J.
Published: October 2013

For the first time an attempt has been made to systematize nonanginal pain questions so that physicians will ask the nonanginal questions and not simply divide all angina‐like symptoms into the two categories of typical and atypical angina. A definite nonanginal chest pain category is defended with the possibility of avoiding diagnoses such as “atypical chest pain” or “atypical angina.” Confidence in diagnosing chest pains as nonanginal can be attained if attention is paid to new criteria for duration, the effect of respiration, arm or chest movement, local compression, and body position. Because of this novel approach to the diagnosis of chest pain, it has become necessary to point out many of the pitfalls into which the unwary may fall with each nonanginal question.
Correlation between R‐wave amplitude and left ventricular volume at rest and with exercise
Authors: Ohlmeier H. , Mannebach H. , Gleichmann U.
Published: October 2013

In 52 patients with exercise angiography (12 normals, 31 with coronary heart disease, 9 with congestive cardiomyopathy) exercise ECGs were examined for R‐wave changes. An increasing R‐wave amplitude was found an insensitive sign of ischemia in patients with coronary heart disease (sensitivity 29%, specificity 81%). Sensitivity and specificity of the observed ST depression in this study were 83% and 71%, respectively, as reported by others. There was no positive correlation between the changes in the R‐wave amplitude and left ventricular end‐diastolic volume during exercise, thus there was no proof of the existence of the so‐called Brody effect in humans.
Reliability of two‐dimensional echocardiography in diagnosing fungal endocarditis
Authors: Sarma R. , Prakash R. , Kaushik V. S. , Oparah S. S. , Mandal A.
Published: October 2013

Although the techniques of M‐mode and two‐dimensional (2D) echocardiography (echo) have been found to be useful in patients with bacterial endocarditis, the 2D findings of fungal endocarditis are not known. In this report, we present the case of a young female narcotic addict with Candida albicans endocarditis in whom we diagnosed a large vegetation by 2D echo. Decision for surgery was made solely on the basis of the 2D‐echo findings. We feel that 2D‐echo findings are reliable in diagnosing fungal endocarditis because, with this technique, the size, shape, mobility, and exact location of the vegetation can be better identified than by the M‐mode echo. In addition, early diagnosis of fungal endocarditis helps in treating the patients with medical and surgical therapy which may result in lower mortality.
Echocardiographic evaluation of responses to left ventricular volume loading by principal components and nomographic analysis
Authors: Conetta D. A. , Carter R. L. , Geiser E. A. , Conti C. R.
Published: October 2013

Changes in performance of left ventricles (LV) with volume overloads are difficult to determine by conventional clinical methods. This information, however, is important for the proper timing of therapeutic interventions to preserve LV function. Seven size‐adjusted (by regression with end‐diastolic diameter, EDD) LV performance parameters from 100 normal echocardiograms (echos) were entered into a principal component analysis (PCA). Two factors (linear combination of the 7 parameters) were obtained from the analysis. Prediction limits (95%) about these two factors used in combination, correctly classified 92% of the normal echos. More detailed analysis of the two PCA factors revealed that the majority of the variability within the factors was explained by size‐adjusted parameters resultant from the EDD posterior wall (factor 1) and EDD septal excursion (factor 2) regressions, respectively. Plots of the 95% prediction limits about these two regression lines provided nomograms. These nomograms used in combination, correctly classified 95% of the normal echos. When the performance parameters of 64 volume loaded ventricles were evaluated by PCA, four groups were identified. Ten ventricles (16%) were hypokinetic, 29 (45%) were hyperkinetic, 23 (36%) were nomokinetic, and 2 (3%) could not be classified. These classifications were supported by significant between group differences of shortening fraction, velocity of circumferential shortening, and velocity of circumferential expansion. Nomographic classification of the same volume loaded hearts was in excellent (94%) agreement with PCA classification. Nomographic analysis (derived from the PCA) is offered as a less complex, more clinically applicable echo method for evaluating LV performance of volume loaded hearts.
Precordial ST—Segment mapping: 6. Evaluation of serial changes in ST‐segment elevations and QRS complexes of precordial maps and standard ECGs in patients with acute myocardial infarction
Authors: Madias J. E.
Published: October 2013

A total of 21 patients, 10 with anterior and 11 with inferior myocardial infarction (MI) had serial precordial 49‐lead ECG maps or standard ECGs on admission, and 2, 6, 12, 24 hours, and 7 days thereafter, to evaluate the natural course of ST‐segment elevation (index of ischemic injury) and QRS changes (index of necrosis), and their relationship. ECG parameters used included the sum of ST‐segment elevations, number of sites showing such changes, the sum of R waves from all leads with ST‐segment elevations, and a QRS score of all leads showing ischemic injury on admission. Sums of ST‐segment elevations either did not show statistically significant change throughout the study or showed unexplained re‐elevation (anterior MI), or completed their downward course in 6 hours (inferior MI). The number of sites showing ST‐segment elevations either remained unchanged (inferior MI), or declined at 2 hours without further change. However changes in the sum of R waves or QRS scores were gradual and completed most of their overall course within 24 hours. Decline of sums of R waves correlated well with sums of ST‐segment elevations on admission (inferior MI), and the number of sites showing changes (anterior MI). The course of changes in QRS complexes is more reliable than the alterations of ST‐segment elevations for the monitoring of evolution of MI. The former, assessed frequently in the first 24 hours, should be useful in the evaluation of therapies for patients with MI.
Serial echocardiograms in patients with congestive cardiomyopathies: Lack of evidence for thrombus formation
Authors: Tobin R. , Slutsky R. A. , Higgins C. B.
Published: October 2013

We studied 90 patients with congestive myocardial disease documented at cardiac catheterization (46 idiopathic, 39 ischemic, and 5 hypertensive) who underwent M‐mode and two‐dimensional echocardiograms every 2–3 months for up to 7 years (mean 3.4 ± 1.6 years, ± 1 S.D.). All had angiographic evidence of severe left ventricular dysfunction (left ventricular ejection fraction < 40%), and were on a variety of inotropic, diuretic, and vasodilating drugs. Only 9 were ingesting anticoagulants (5 warfarin and 4 aspirin), those on warfarin had documented pulmonary emboli or deep venous thrombosis. All but 4 patients were in normal sinus rhythm. Only one subject in this group was found to have a myocardial (left ventricular) thrombus. Postmortem examinations of 27 patients confirmed the ultrasound data. Thus, we conclude that cardiac thrombi are unusual in patients with congestive cardiomyopathies and rarely develop over the course of the illness even in the absence of chronic anticoagulation.
PET Radiotracers for Imaging P‐glycoprotein: The Challenge for Early Diagnosis in AD
Authors: Leopoldo Marcello , Contino Marialessandra , Berardi Francesco , Perrone Roberto , Colabufo Nicola Antonio
Published: October 2013

PET radiotracer development to target in vivo P‐glycoprotein (P‐gp) could be an important strategy for the early diagnosis of neurodegenerative disorders such as Alzheimer’s disease (AD). Indeed, as a dysfunction of P‐gp is responsible for the accumulation of β‐amyloid plaques (a hallmark of AD) in brain parenchyma, P‐gp is the cause of AD onset. P‐gp substrates and inhibitors are useful for imaging the activity or expression of this protein, respectively; herein we discuss the in vivo evaluation of some 11C radiotracers with P‐gp‐inhibitory activity, such as [11C]MC18 and [11C]MC113, as well as P‐gp substrates [11C]MC266 and [11C]MC80. Moreover, the radiosynthesis of all these P‐gp probes is reported.
A Novel Mechanism for the Extraction of Metals from Water to Ionic Liquids
Authors: Janssen Camiel H. C. , Sánchez Antonio , Witkamp Geert‐Jan , Kobrak Mark N.
Published: October 2013

We present a novel mechanism for the extraction of metals from aqueous phases to room‐temperature ionic liquids (ILs) by use of a high‐temperature salt as an extraction agent. The mechanism capitalizes on the fact that charged metal complexes are soluble in ILs; this allows for extraction of charged complexes rather than the neutral species, which are formed by conventional approaches. The use of a well‐chosen extraction agent also suppresses the competing ion‐exchange mechanism, thus preventing degradation of the ionic liquid. The approach permits the use of excess extractant to drive the recovery of metals in high yield. This work presents both a thermodynamic framework for understanding the approach and experimental verification of the process in a range of different ILs. The method has great potential value in the recovery of metals, water purification and nuclear materials processing.
Toward a formalism of modeling and simulation using model theory
Authors: Diallo Saikou Y. , Padilla Jose J. , Gore Ross , Herencia‐zapana Heber , Tolk Andreas
Published: October 2013

This article proposes a Modeling and Simulation (M&S) formalism using Model Theory. The article departs from the premise that M&S is the science that studies the nature of truth using models and simulations. Truth in models and simulations is relative as they seek to answer specific modeling questions. Consequently, truth in M&S is relative because every model is a purposeful abstraction of reality. We use Model Theory to express the proposed formalism because it is built from the premise that truth is relative. The proposed formalism allows us to: (1) deduce formal definitions and explanations of areas of study in M&S, including conceptual modeling, validity, and interoperability, and (2) gain insight into which tools can be used to semi‐automate validation and interoperation processes. © 2013 Wiley Periodicals, Inc. Complexity 19: 56–63, 2014
Anticoagulation and Monitoring of a Novel and Reversible Factor IXa Inhibitor
Authors: Becker Richard C. , Chan Mark Y. , Vavalle John P. , Povsic Thomas J.
Published: October 2013

Clinical Development Phases I‐III Regulatory, Quality, Manufacturing

Thrombosis as a clinical phenotype is ubiquitous in human diseases and conditions, ranging from atherosclerosis and other vascular disorders to trauma, surgery, malignancy, infections, blood dyscrasias, auto‐immunity, and complications of pregnancy. While each condition carries its own distinct signature and predisposition for thrombosis as a nonphysiological event, there are several common themes that center on cellular and noncellular elements, including well‐characterized coagulation proteases. Over the past decade, our group has been actively involved with the development of a factor IXa inhibitor, pegnivacogin, and its complementary antidote or control agent, anivamersen. The following review provides a summary of fundamental constructs, milestones, and the current status of our translational journey.
The contrasted evolutionary fates of deep‐sea chemosynthetic mussels (Bivalvia, Bathymodiolinae)
Authors: Thubaut Justine , Puillandre Nicolas , Faure Baptiste , Cruaud Corinne , Samadi Sarah
Published: October 2013

Bathymodiolinae are giant mussels that were discovered at hydrothermal vents and harboring chemosynthetic symbionts. Due to their close phylogenetic relationship with seep species and tiny mussels from organic substrates, it was hypothesized that they gradually evolved from shallow to deeper environments, and specialized in decaying organic remains, then in seeps, and finally colonized deep‐sea vents. Here, we present a multigene phylogeny that reveals that most of the genera are polyphyletic and/or paraphyletic. The robustness of the phylogeny allows us to revise the genus‐level classification. Organic remains are robustly supported as the ancestral habitat for Bathymodiolinae. However, rather than a single step toward colonization of vents and seeps, recurrent habitat shifts from organic substrates to vents and seeps occurred during evolution, and never the reverse. This new phylogenetic framework challenges the gradualist scenarios “from shallow to deep.” Mussels from organic remains tolerate a large range of ecological conditions and display a spectacular species diversity contrary to vent mussels, although such habitats are yet underexplored compared to vents and seeps. Overall, our data suggest that for deep‐sea mussels, the high specialization to vent habitats provides ecological success in this harsh habitat but also brings the lineage to a kind of evolutionary dead end.
TLRs control hematopoiesis during infection
Authors: Yáñez Alberto , Goodridge Helen S. , Gozalbo Daniel , Gil M. Luisa
Published: October 2013

Recent research has shown that (i) Toll‐like receptor (TLR) agonists drive hematopoietic stem and progenitor cells (HSPCs) to proliferate and differentiate along the myeloid lineage in vitro, and (ii) direct TLR‐mediated stimulation of HSPCs also promotes macrophage differentiation in vivo following infection. These new insights demonstrate that TLR signaling in HSPCs, in addition to other TLR‐dependent mechanisms, can contribute to HSPC expansion and myeloid differentiation after infection. Evidence is, therefore, mounting that direct TLR‐induced programming of hematopoiesis plays a key role in host defense by rapidly replenishing the innate immune system with the cells needed to deal with pathogens.
Trinuclear Diamagnetic Nickel(II) Complexes with Bridging 3‐Arylpyrazolato Ligands
Authors: Salih Kifah S. M. , Bergner Susann , Kelm Harald , Sun Yu , Grün Anneken , Schmitt Yvonne , Schoch Roland , Busch Mark , Deibel Naina , Bräse Stefan , Sarkar Biprajit , Bauer Matthias , Gerhards Markus , Thiel Werner R.
Published: October 2013

Orange‐red trinuclear nickel(II) complexes are obtained by reacting Ni(ClO4)2(H2O)6 with 3(5)‐arylpyrazoles in the presence of a base. Herein, the diamagnetic nickel centers are coordinated in a square‐pyramidal manner by four pyrazolato ligands, each of which bridges two nickel sites. The structurally unique complexes were investigated by NMR, IR, fluorescence, and X‐ray spectroscopy. All seven compounds described here were structurally elucidated by single‐crystal X‐ray diffraction. With 3(5)‐ferrocenylpyrazole as the substrate, a nonametallic system that possesses six redox‐active ferrocenyl moieties was obtained.
Donor‐Stabilized Silylenes with Guanidinato Ligands
Authors: Mück Felix M. , Junold Konstantin , Baus Johannes A. , Burschka Christian , Tacke Reinhold
Published: October 2013

The first donor‐stabilized silylenes with guanidinato ligands, compounds 4 and 6, were synthesized and structurally characterized in the solid state and in solution. As demonstrated by single‐crystal X‐ray diffraction studies, compound 4 contains a bidentate and a monodentate guanidinato ligand of the type [iPrNC(NiPr2)NiPr]–, and compound 6 contains the bidentate guanidinato ligand [ArNC(NMe2)NAr]– (Ar = 2,6‐diisopropylphenyl) and the monodentate amido ligand [(Me3Si)2N]–. Both silicon(II) complexes exist also in solution.
The Voltammetry and Electroanalysis of Some Estrogenic Compounds at Modified Diamond Electrodes
Authors: Gan Patrick , Compton Richard G. , Foord John S.
Published: October 2013

The voltammetry of some estrogenic compounds (estradiol, nonylphenol, bisphenol A, ethynylestradiol, estrone, estriol) in aqueous solution at boron doped diamond electrodes is reported. For oxidised (hydrophilic) electrodes electrochemically irreversible kinetics were observed for the diffusing molecules allowing the inference of diffusion coefficients and transfer coefficients. In contrast for hydrogen terminated (hydrophobic) surfaces significant adsorption was observed. A limit of detection of 1–100 µM for the estrogenic compounds was found using the oxidised diamond electrode. Surface modification of the oxidised diamond with nano‐Carbon (so‐called Carbon Black) allowed preconcentration of the target by adsorption onto the Carbon Black prior to analysis and a corresponding reduction of the limit of detection by ca three orders of magnitude to 5–100 nM.
Square‐Wave Voltammetry: A Review on the Recent Progress
Authors: Mirceski Valentin , Gulaboski Rubin , Lovric Milivoj , Bogeski Ivan , Kappl Reinhard , Hoth Markus
Published: October 2013

A review on the recent progress of square‐wave voltammetry is presented, covering the period of the last five years. The review addresses the new theoretical development of the technique as well as its application for mechanistic purposes, electrode kinetic measurements, biochemical and analytical applications. Besides, a few novel methodological modifications are proposed that might expand the scope and application of the technique.
Recent advances in coupling capillary electrophoresis‐based separation techniques to ESI and MALDI‐MS
Authors: Zhong Xuefei , Zhang Zichuan , Jiang Shan , Li Lingjun
Published: October 2013

Coupling CE‐based separation techniques to MS creates a powerful platform for analysis of a wide range of biomolecules from complex samples because it combines the high separation efficiency of CE and the sensitivity and selectivity of MS detection. ESI and MALDI, as the most common soft ionization techniques employed for CE and MS coupling, offer distinct advantages for biomolecular characterization. This review is focused primarily on technological advances in combining CE and chip‐based CE with ESI and MALDI‐MS detection in the past five years. Selected applications in the analyses of metabolites, peptides, and proteins with recently developed CE‐MS platforms are also highlighted.
PRAS40 prevents development of diabetic cardiomyopathy and improves hepatic insulin sensitivity in obesity
Authors: Völkers Mirko , Doroudgar Shirin , Nguyen Nathalie , Konstandin Mathias H , Quijada Pearl , Din Shabana , Ornelas Luis , Thuerauf Donna J , Gude Natalie , Friedrich Kilian , Herzig Stephan , Glembotski Christopher C , Sussman Mark A
Published: October 2013

Diabetes is a multi‐organ disease and diabetic cardiomyopathy can result in heart failure, which is a leading cause of morbidity and mortality in diabetic patients. In the liver, insulin resistance contributes to hyperglycaemia and hyperlipidaemia, which further worsens the metabolic profile. Defects in mTOR signalling are believed to contribute to metabolic dysfunctions in diabetic liver and hearts, but evidence is missing that mTOR activation is causal to the development of diabetic cardiomyopathy. This study shows that specific mTORC1 inhibition by PRAS40 prevents the development of diabetic cardiomyopathy. This phenotype was associated with improved metabolic function, blunted hypertrophic growth and preserved cardiac function. In addition PRAS40 treatment improves hepatic insulin sensitivity and reduces systemic hyperglycaemia in obese mice. Thus, unlike rapamycin, mTORC1 inhibition with PRAS40 improves metabolic profile in diabetic mice. These findings may open novel avenues for therapeutic strategies using PRAS40 directed against diabetic‐related diseases.
Mathematical Model of Proton Exchange Membrane Fuel Cell with Consideration of Water Management
Authors: Yin K.‐M. , Hsuen H.‐K.
Published: October 2013

One‐dimensional model on the membrane electrode assembly (MEA) of proton exchange membrane fuel cell is proposed, where the membrane hydration/dehydration and the possible water flooding of the respective cathode and anode gas diffusion layers are considered. A novel approach of phase‐equilibrium approximation is proposed to trace the water front and the detailed saturation profile once water emerges in either anode or cathode gas diffusion layer. The approach is validated by a semi‐analytical method published earlier. The novel approach is applicable to the polarization regime from open circuit voltage to the limiting current density under practical operation conditions. Oxygen diffusion is limited by water accumulation in the cathode gas diffusion layer as current increases, caused by excessive water generation at the cathode catalyst layer and the electro‐osmotic drag across the membrane. The existence of liquid water in the anode gas diffusion layer is predicted at low current densities if high degrees of humidification in both anode and cathode feeds are employed. The influences of inlet relative humidity, imposed pressure drop, and cell temperature are correlated well with the cell performance. In addition, the overpotentials attributed from individual components of the MEA are delineated against the cell current densities.
Two‐Stage Oxidation of Glucose by an Enzymatic Bioanode
Authors: Matsumoto T. , Shimada S. , Yamamoto K. , Tanaka T. , Kondo A.
Published: October 2013

The present study reports the design of a novel bioanode to deeply oxidize glucose in an enzymatic biofuel cell (EFC). This enzymatic glucose cell utilizes three co‐immobilized enzymes: NAD‐dependent glucose dehydrogenase (GDH), NAD(P)+‐dependent gluconate‐5‐dehydrogenase (Ga5DH), and diaphorase (DI). Glucose is oxidized to gluconate by NAD‐dependent GDH, gaining two electrons per glucose; the gluconate obtained as a by‐product is oxidized at the C5 carbon to 5‐keto‐gluconate by Ga5DH. Operation of our bioanode enabled the oxidation of glucose in two stages, resulting in the gain of four electrons. The three‐enzyme EFC provides a maximum power density of 10.51 ± 1.72 μW cm–2, which is about 1.6 times higher than the maximum power density of an EFC using a bioanode based on the co‐immobilization of two enzymes (GDH and DI). Our results hold promise for increasing the current density of EFCs, and for application in glucose biosensor.
The Synthesis of N,N‐Bis(dialkoxyphosphinoylmethyl)‐ and N,N‐Bis(diphenylphosphinoylmethyl)glycine Esters by the Microwave‐Assisted Double Kabachnik–Fields Reaction
Authors: Bálint Erika , Fazekas Eszter , Drahos László , Keglevich György
Published: October 2013

The condensation of a glycine ester, two equivalents of paraformaldehyde, and the same quantity of a dialkyl phosphite or diphenylphosphine oxide afforded the title compounds as new bis(phospha‐Mannich) products under microwave (MW) conditions at 100°C. The dialkoxyphosphinoylmethyl derivatives were synthesized under solvent‐free conditions, whereas the diphenylphosphinoylmethyl derivatives were synthesized in acetonitrile solution. Comparative thermal experiments showed the beneficial role of MW in respect of efficiency.
Association between severe treatment‐related lymphopenia and progression‐free survival in patients with newly diagnosed squamous cell head and neck cancer
Authors: Campian Jian L. , Sarai Guneet , Ye Xiaobu , Marur Shanthi , Grossman Stuart A.
Published: October 2013

Background

Severe treatment‐related lymphopenia occurs commonly in many cancers and is associated with early tumor progression. Data are lacking as to whether this occurs in squamous cell head and neck cancer.

Methods

Serial total lymphocyte counts were retrospectively reviewed in patients with newly diagnosed squamous head and neck cancer undergoing chemoradiation and associated with treatment outcomes.

Results

The median baseline total lymphocyte count in 56 patients was 1660 cells/mm3, which fell by 73% to 445 cells/mm3 2 months after initiating chemoradiation (p < .0001). Human papillomavirus negative (HPV‐) patients with a total lymphocyte count <500 cells/mm3 at 2 months had significantly earlier disease progression than those with higher total lymphocyte counts (hazard ratio [HR], 5.75; p = .045).

Conclusion

Baseline total lymphocyte counts were normal, but at 2 months approximately 60% of patients had severe treatment‐related lymphopenia regardless of HPV status. Severe treatment‐related lymphopenia in HPV‐ patients is independently associated with earlier disease progression. Prospective studies are needed to confirm these findings, which suggest that immune preservation is important in this cancer. © 2014 Wiley Periodicals, Inc. Head Neck 36: 1747–1753, 2014
Age‐dependent role for Ras‐GRF1 in the late stages of adult neurogenesis in the dentate gyrus
Authors: Darcy Michael J. , Trouche Stéphanie , Jin Shan‐Xue , Feig Larry A.
Published: October 2013

The dentate gyrus of the hippocampus plays a pivotal role in pattern separation, a process required for the behavioral task of contextual discrimination. One unique feature of the dentate gyrus that contributes to pattern separation is adult neurogenesis, where newly born neurons play a distinct role in neuronal circuitry. Moreover, the function of neurogenesis in this brain region differs in adolescent and adult mice. The signaling mechanisms that differentially regulate the distinct steps of adult neurogenesis in adolescence and adulthood remain poorly understood. We used mice lacking RAS‐GRF1 (GRF1), a calcium‐dependent exchange factor that regulates synaptic plasticity and participates in contextual discrimination performed by mice, to test whether GRF1 plays a role in adult neurogenesis. We show Grf1 knockout mice begin to display a defect in neurogenesis at the onset of adulthood (∼2 months of age), when wild‐type mice first acquire the ability to distinguish between closely related contexts. At this age, young hippocampal neurons in Grf1 knockout mice display severely reduced dendritic arborization. By 3 months of age, new neuron survival is also impaired. BrdU labeling of new neurons in 2‐month‐old Grf1 knockout mice shows they begin to display reduced survival between 2 and 3 weeks after birth, just as new neurons begin to develop complex dendritic morphology and transition into using glutamatergic excitatory input. Interestingly, GRF1 expression appears in new neurons at the developmental stage when GRF1 loss begins to effect neuronal function. In addition, we induced a similar loss of new hippocampal neurons by knocking down expression of GRF1 solely in new neurons by injecting retrovirus that express shRNA against GRF1 into the dentate gyrus. Together, these findings show that GRF1 expressed in new neurons promotes late stages of adult neurogenesis. Overall our findings show GRF1 to be an age‐dependent regulator of adult hippocampal neurogenesis, which contributes to ability of mice to distinguish closely related contexts. © 2013 Wiley Periodicals, Inc.
Glial cell line‐derived neurotrophic factor sensitized the mechanical response of muscular thin‐fibre afferents in rats
Authors: Murase S. , Kato K. , Taguchi T. , Mizumura K.
Published: October 2013

Background

The role of glial cell line‐derived neurotrophic factor (GDNF) in pain and muscular nociceptor activities is not well understood. We examined pain‐related behaviour and mechanical response of muscular thin‐fibre afferents after intramuscular injection of GDNF in rats.

Methods

GDNF and antagonist to transient receptor potential V1 or acid‐sensing ion channels were injected into rat gastrocnemius muscle and muscular mechanical hyperalgesia was assessed with a Randall–Selitto analgesiometer. Activities of single C‐ (conduction velocity < 2.0 m/s) and Aδ‐fibres (conduction velocity 2.0–12.0 m/s) were recorded from extensor digitorum longus muscle–nerve preparations in vitro. The changes in the responses to mechanical stimuli before and after GDNF injection were recorded.

Results

Mechanical hyperalgesia was observed from 1 h to 1 day after GDNF (0.03 μM, 20 μL) injection. The decreased withdrawal threshold was temporarily reversed after intramuscular injection of amiloride (50 mM, 20 μL), but not capsazepine (50 μM, 20 μL). In single‐fibre recordings, both phosphate buffered saline (PBS) and GDNF failed to induce any significant discharges. GDNF significantly enhanced the mechanical response when compared with the PBS group, but only in Aδ‐fibre afferents. C‐fibres were not affected. Significantly lowered threshold and increased response magnitude to mechanical stimuli were observed 30 or 60–120 min after injection. These times are compatible with the timing of the onset of the hyperalgesic effect of GDNF.

Conclusions

These results suggest that GDNF increased the response of muscular Aδ‐fibre afferents to mechanical stimuli, resulting in muscular mechanical hyperalgesia.
Sources and sinks of entropy in the atmosphere
Authors: Raymond David J.
Published: October 2013

Moist entropy is generally treated as a conserved variable in atmospheric models in the absence of external heat and moisture sources such as radiation and surface fluxes. However, both irreversible generation and nonadvective transport of entropy occur in the atmosphere, with many of these associated with moisture and precipitation. These entropy sources and sinks are needed to balance the global entropy budget. Existing work on calculating the irreversible generation of entropy and nonadvective transport is extended to include the major effects of ice.
Hamiltonian replica‐exchange simulations with adaptive biasing of peptide backbone and side chain dihedral angles
Authors: Ostermeir Katja , Zacharias Martin
Published: October 2013

A Hamiltonian Replica‐Exchange Molecular Dynamics (REMD) simulation method has been developed that employs a two‐dimensional backbone and one‐dimensional side chain biasing potential specifically to promote conformational transitions in peptides. To exploit the replica framework optimally, the level of the biasing potential in each replica was appropriately adapted during the simulations. This resulted in both high exchange rates between neighboring replicas and improved occupancy/flow of all conformers in each replica. The performance of the approach was tested on several peptide and protein systems and compared with regular MD simulations and previous REMD studies. Improved sampling of relevant conformational states was observed for unrestrained protein and peptide folding simulations as well as for refinement of a loop structure with restricted mobility of loop flanking protein regions. © 2013 Wiley Periodicals, Inc.
Spectroscopic Analysis of the Products of the Cycloaddition Reaction of 1‐Aryl‐2‐chlorocyclopropenes and Cyclopentadiene
Authors: Ding Mei‐Fang , Lee Chuan‐Chen , Lin Lian‐Chun , Lin Shaw‐Tao
Published: October 2013

The treatment of a series of 1‐aryl‐2,2‐dihalocyclopropanes with t‐BuOK at −10 °C produces the corresponding 1‐aryl‐2‐halocyclopropenes, which react with cyclopentadiene to produce fairly good yield of [4+2]‐cycloaddition products with more than 90% of the endo‐isomer. The higher yield obtained from hexane medium then from methanol and ionic liquid demonstrates that the reaction is a nonpolar process.
Anode direct contact for enhancing power generation and biofouling reduction in ultrafiltration microbial fuel cells
Authors: Kim Kyoung‐Yeol , Yang Euntae , Lee Mi‐Young , Chae Kyu‐Jung , Kim Sung‐Jo , Kim In S.
Published: October 2013

BACKGROUND

An ultrafiltration microbial fuel cell (UF‐MFC) is a novel technology that can simultaneously produce high‐quality effluent and electricity during wastewater treatment. To increase the power density and mitigate the inevitable biofouling phenomena in UF‐MFCs, the anode direct contact (ADC) method was tested. ADC application in UF‐MFCs improves the power densities by reducing the distance between the anode electrode and UF membrane (lowering the internal resistance), and mitigates biofouling on the UF membrane surface due to the direct contact of the porous anode electrode with the membrane surface.

RESULTS

The maximum power density increased from 76.6 ± 2.5 mW m−2 to 129.4 ± 13.9 mW m−2 after applying the ADC, with the internal resistance decreasing from 0.49 Ω m2 to 0.23 Ω m2. The concentrations of extracellular polymeric substances (EPS) and total cell number were also analyzed as indicators for measuring biofouling on the UF membrane surface. EPS proteins and total cell numbers were reduced (62.8% and 64.9% each) with ADC application after 70 h operation, though no differences were observed in the specific permeate flux.

CONCLUSION

ADC application is simple and its use can enhance the power densities and mitigate the biofouling phenomena of UF‐MFCs. © 2013 Society of Chemical Industry
Synthesis and Structural Characterization of Pyrrole Heterocyclic Systems Bearing Amino Acid Units: Novel Pyrrol‐3‐ones, Pyrrolo[1,2‐a][3,1]benzoxazines, and Pyrrolo[2,1‐b][1,3]oxazoles
Authors: Koca İrfan , Saçmacı Mustafa , Yılmaz Filiz , Üngören Şevket Hakan
Published: October 2013

Furan‐3‐one derivatives 1 were converted into 2‐hydroxy‐pyrrole‐3‐ones 4 by reacting with various α‐ and β‐amino acids. In contrast, the reaction of furan‐3‐ones and 1‐aminocyclobutanecarboxylic acid afforded spiro‐pyrrolo[2,1‐b][1,3]oxazoles 5 via the pyrrole‐3‐one intermediate under the same reaction conditions. Some of 2‐hydroxy‐pyrrole‐3‐ones 3 derived from anthranilic acids were transformed to pyrrolo[1,2‐a][3,1]benzoxazines via intramolecular esterification.
What's cost got to do with it? Association between hospital costs and frequency of admissions among “high users” of hospital care
Authors: Kieu Nguyen Oanh , Tang Ning , Hillman John M. , Gonzales Ralph
Published: October 2013

BACKGROUND

Efforts to curb healthcare spending have included interventions that target frequently hospitalized individuals. It is unclear the extent to which the most frequently hospitalized individuals also represent the costliest individuals.

OBJECTIVE

To examine the relationship between 2 types of “high users” commonly targeted in cost‐containment interventions—those incurring the highest hospital costs (“high cost”) and those incurring the highest number of hospitalizations (“high admit”).

DESIGN, SETTING, AND PATIENTS

Cross‐sectional study of 2566 individuals with a primary care physician and at least 1 hospitalization within an academic health system from 2010 to 2011.

MEASUREMENTS

Overlap between the population constituting the top decile of hospital costs and the population constituting the top decile of hospitalizations; characteristics of the 3 resulting high user subgroups.

RESULTS

Only 48% of individuals who were high cost (>$65,000) were also high admit (≥3 hospitalizations). Compared to hospitalizations incurred by high cost–high admit individuals (n = 605), hospitalizations incurred by high cost–low admit individuals (n = 206) were more likely to be for surgical procedures (58 vs 22%, P < 0.001), had a higher cost ($68,000 vs $28,000, P < 0.001), longer length of stay (10 vs 5 days, P < 0.001), and were less likely to be a 30‐day readmission (17 vs 47%, P < 0.001).

CONCLUSIONS

Stratifying high admit individuals by costs and high cost individuals by hospitalizations yields 3 distinct high user subgroups with important differences in clinical characteristics and utilization patterns. Consideration of these distinct subgroups may lead to better‐tailored interventions and achieve greater cost savings. Journal of Hospital Medicine 2013;8:665–671. © 2013 Society of Hospital Medicine.
Gadoxetate disodium in patients with primary sclerosing cholangitis: An analysis of hepatobiliary contrast excretion
Authors: Ringe Kristina I. , Hinrichs Jan , Merkle Elmar M. , Weismüller Tobias J. , Wacker Frank , Meyer Bernhard C.
Published: October 2013

Purpose

To assess hepatobiliary excretion of gadoxetate disodium in patients with primary sclerosing cholangitis (PSC) over time and to determine a possible correlation with severity of the disease.

Materials and Methods

A total of 111 patients (36 females, 75 males, mean age 41.5 yr) with confirmed diagnosis of PSC who underwent gadoxetate disodium enhanced hepatic MRI were included in this retrospective institutional review board‐approved study. Hepatocyte phase images (10–493 min post injection [p.i.]) were evaluated by one radiologist for the presence of contrast agent in the intrahepatic bile ducts (IBD), common bile duct (CBD), gallbladder (GB), and duodenum. In 54 patients, in whom hepatocyte phase scans were acquired within 10–20 min p.i., hepatobiliary excretion was compared with data collected in a previous study from patients without liver disease (controls; Mann‐Whitney U‐test). Excretion was further correlated with liver function tests (Kruskal‐Wallis test).

Results

Compared with controls, excretion was significantly delayed in patients with PSC: 20 min p.i. gadoxetate disodium could be detected in the IBD in 55.6% (controls:100%), CBD 53.7% (controls:100%), GB 39.6% (controls:87%), duodenum 13% (controls:66%), respectively. Contrast appearance in different bile duct sections increased over time and correlated significantly with serum bilirubin and AP levels (P < 0.05).

Conclusion

Hepatobiliary excretion of gadoxetate disodium in PSC patients is significantly delayed. Excretion correlates with bilirubin levels, and thus indirectly with severity of disease. J. Magn. Reson. Imaging 2014;40:106–112. © 2013 Wiley Periodicals, Inc.
High prevalence of HCMV and viral load in tumor tissues and peripheral blood of glioblastoma multiforme patients
Authors: dos Santos Claudia Januário , Stangherlin Lucas Matheus , Figueiredo Eberval Gadelha , Corrêa Clemar , Teixeira Manoel Jacobsen , da Silva Maria Cristina Carlan
Published: October 2013

Glioblastoma multiforme is the most prevalent and malignant tumor of the central nervous system. In the last few years, accumulating evidence has suggested an association between human cytomegalovirus (HCMV) infection and glioblastoma multiforme. In this study, tumor tissues and peripheral blood of patients with glioblastoma multiforme were examined for the presence of HCMV DNA. Twenty‐two fresh surgical brain specimens and 20 peripheral blood samples were analyzed by real‐time PCR (qPCR) and hemi‐nested PCR (nPCR) for the presence of pp65 and (glycoprotein B) gB viral genomic regions, respectively. HCMV DNA was detected in the majority of the tumor samples analyzed (95% by qPCR and 91% by nPCR). About half of the patients with tumors positive for HCMV also had detectable viral DNA in their peripheral blood (47% by qPCR and 61% by nPCR). Genome copy numbers were determined and in the majority of the tumor samples cellular DNA outnumbers viral DNA (average of 1 infected cell in 33 cells). The gB genotypes were determined in HCMV‐positive samples and gB2 was the most prevalent genotype in the tumor and blood samples. The results show a high prevalence of HCMV in glioblastoma multiforme samples reinforcing a possible association between HCMV infection and tumor development. J. Med. Virol. 86:1953–1961, 2014. © 2013 Wiley Periodicals, Inc.
Surface enhanced Raman scattering of molecules related to highly ordered gold cavities
Authors: Gu Zhuomin , Tian Shu , Zhou Qun , Wei Wenjuan , Zhao Lili , Li Xiaowei , Zheng Junwei
Published: October 2013

We presented a controlled particles‐in‐cavity (PIC) pattern for surface‐enhanced Raman scattering (SERS) detection. The periodic gold cavity array was fabricated by electrodeposition using highly ordered polystyrene spheres as a template. The as‐prepared gold cavities can be used as a SERS active substrate with significant spectral enhancement and reproducibility, which was evaluated by SERS signals using 4‐mercaptobenzoic acid (4‐MBA) as probe molecules. The surface of these gold cavities was further functionalized with cetyltrimethylammonium bromide molecules, which may immobilize the 4‐MBA‐modified silver nanoparticles in the gold cavity to form a PIC structure via the electrostatic interaction. We have demonstrated that there exists a pH window for the immobilization of the nanoparticles inside cavities. Therefore, the silver nanoparticles can be selectively immobilized into the functionalized gold cavities under the optimized pH value of the media. Further enhancement of the Raman scattering of the labeled molecules can be achieved due to the interconnection between the silver nanoparticles and gold cavity. Copyright © 2013 John Wiley & Sons, Ltd.