bluuebunny/crossref_metadata_2025 huggingface dataset:
Term Limits and Legislative‐Executive Conflict in the American States
Authors: Baker Travis J. , Hedge David M.
Published: April 2013

State governments have experienced considerable institutional change in the last several decades. None appeared at first glance to be as far‐reaching as the legislative term limits that were adopted by over 20 states in the 1990s. The evidence to date suggests that term limits have indeed changed the character of many of the states' legislatures, if not always as predicted by their advocates. We report data on veto dynamics over the period 1989–2008 to determine how term limits have impacted legislative‐executive relations. Our data both challenge and support what has become the conventional wisdom, i.e., that term limits will weaken legislatures relative to their governors. States with more stringent term limits experienced fewer gubernatorial vetoes but proved more likely to override those vetoes when they were issued. Taken together the evidence suggests that the relationship between governors and legislatures in the wake of term limits is more complex and variable than scholars and others had previously thought.
HCVclearance from saliva ofHIV–HCV‐coinfected patients on treatment with interferon plus ribavirin
Authors: Feijoo J , Eirea M , Limeres J , Abeleira M , Ramos I , Ocampo A , Diz P
Published: April 2013

Objective

To determine hepatitis C virus (HCV)RNAclearance from blood and saliva ofHIV–HCV‐coinfected patients undergoing combined therapy with pegylated interferon plus ribavirin (PEG‐IFN‐RIB).

Subjects and Methods

Study group was formed of 60HIV‐infected patients with chronic hepatitis C who were starting treatment withPEG‐IFN‐RIB. Blood and saliva samples were taken at baseline, at the end of treatment and 24 and 48 weeks later. A nestedRT‐PCRtechnique was used to detectHCV‐RNAin saliva.

Results

HCV‐RNAwas detected in saliva at baseline in 64.7% of patients. Thirty‐four patients completed follow‐up. The response rate (undetectableHCV‐RNA) in blood was 79.4% at the end of treatment; 55.8% at 24 weeks after the end of treatment and 50% at 48 weeks.HCVwas detected in saliva of 13 (38.2%) patients at the end of treatment and in 18 (52.9%) patients at 24 and 48 weeks later. Concordance ofHCVclearance from blood and saliva reached its maximum value at 48 weeks after the end of treatment (odds ratio, 112.51).

Conclusion

InHIV–HCV‐coinfected patients responders toPEG‐IFN‐RIB, the salivary glands do not appear to be a sanctuary site forHCV, although viral clearance from saliva may be slower than from blood.
The Interaction between Negative Emotionality and Effortful Control in Early Social‐emotional Development
Authors: Moran Lyndsey R. , Lengua Liliana J. , Zalewski Maureen
Published: April 2013

Interactions between reactive and regulatory dimensions of temperament may be particularly relevant to children's adjustment but are examined infrequently. This study investigated these interactions by examining effortful control as a moderator of the relations of fear and frustration reactivity to children's social competence, internalizing, and externalizing problems. Participants included 306 three‐year‐old children and their mothers. Children's effortful control was measured using observational measures, and reactivity was assessed with both observational and mother‐reported measures. Mothers reported on children's adjustment. Significant interactions indicated that children with higher mother‐reported fear or higher observed frustration and lower executive control showed higher externalizing problems whereas children with higher observed fear and higher delay ability demonstrated lower externalizing problems. These results highlight effortful control as a moderator of the relation between reactivity and adjustment, and may inform the development of interventions geared toward the management of specific negative affects.
Investigating Essential Characteristics of Scientific Practices in Elementary Science Learning Environments: The Practices of Science Observation Protocol (P‐SOP)
Authors: Forbes Cory T. , Biggers Mandy , Zangori Laura
Published: April 2013

Within the field of science education, there remains little agreement as to the definition and characteristics of classroom inquiry. The emerging emphasis on scientific practices in science education reform discourse is underpinned by a need to better articulate the constituent elements of inquiry‐based science. While a small number of observation‐based instruments have been developed to characterize science learning environments, few are explicitly aligned with theoretical constructs articulated by the National Research Council and/or have been substantially field‐tested. We employ a newly developed instrument, the Practices of Science Observation Protocol (P‐SOP), to investigate essential features of inquiry and scientific practices in which early learners engage in elementary classrooms. This research is part of a multiyear professional development program designed to support elementary teachers (K‐5) in a large, urban school district to learn to better engage students in scientific practices. Project teachers video‐recorded enacted science lessons (n = 124) which were used as data. Findings illustrate both essential features of inquiry and scientific practices observed in elementary classrooms, as well as establish the P‐SOP as a valid and reliable observation protocol. These findings have important implications for the design of elementary science learning environments and associated research and development efforts in the field.
Comparison of the two fully automated anti‐HCMV IgG assays: Abbott Architect CMV IgG assay and Biotest anti‐HCMV recombinant IgG ELISA
Authors: Juhl D. , Vockel A. , Luhm J. , Ziemann M. , Hennig H. , Görg S.
Published: April 2013

Objective and Background

To assess the performance characteristics of two fully automated human cytomegalovirus (HCMV) antibody tests.

Materials and Methods

Samples from negatively or not pre‐screened blood donors were tested by the Biotest anti‐HCMV recombinant IgG enzyme‐linked immunosorbent assay (ELISA) in comparison to the Abbott Architect CMV IgG assay [chemiluminescent microparticle immunoassay (CMIA)]. For clarification, samples with discordant results between both assays were subjected to supplemental testing for anti‐HCMV IgG, IgM and HCMV DNA in plasma.

Results

From 4938 samples tested, 362 delivered positive results in both assays (7·3%). 91 (1·8%) samples were discordant. Of 43 (two not further tested) samples positive only by ELISA, 41 were false positive, one true positive and one indeterminate. Of 45 (one not further tested) samples positive only by CMIA, 20 were false positive, 9 indeterminate and 16 true positive. Anti‐HCMV IgM and HCMV DNA testing from the plasma were negative in indeterminate samples. Considering the results of supplemental testing, the CMIA achieved altogether better results concerning resolved sensitivity, resolved specificity as well as negative predictive value. Both assays had an inferior positive predictive value, with a better result for CMIA.

Conclusion

Overall, the performance characteristics of the CMIA were better than those of the ELISA. Owing to the inferior positive predictive value, positive test results require confirmation if blood products from donors with remote HCMV infection should be administered.
Direct Evidence of a Dinuclear Copper Intermediate in Cu(I)-Catalyzed Azide-Alkyne Cycloadditions
Authors: Worrell B. T. , Malik J. A. , Fokin V. V.
Published: April 2013

How Copper Clicks

The copper-catalyzed coupling of azides and alkynes has been termed a “click” reaction on account of its efficiency and versatility, but despite its widespread use, the mechanism remains somewhat unclear. Through a series of kinetic and isotopic labeling studies,

Worrell
et al.

(p.
457
, published online 4 April) show that, in the case of terminal alkynes (capped at one end by an H atom), two equivalents of copper participate in activating each molecule's reactivity toward azide. Surprisingly, the reaction also appears to proceed through an intermediate in which the two copper centers become equivalent and functionally exchangeable, despite initially coordinating to distinct sites on the alkyne.
Neural Decoding of Visual Imagery During Sleep
Authors: Horikawa T. , Tamaki M. , Miyawaki Y. , Kamitani Y.
Published: April 2013

Reading Dreams

How specific visual dream contents are represented by brain activity is unclear. Machine-learning–based analyses can decode the stimulus- and task-induced brain activity patterns that represent specific visual contents.

Horikawa
et al.

(p.
639
, published online 4 April) examined patterns of brain activity during dreaming and compared these to waking responses to visual stimuli. The findings suggest that the visual content of dreams is represented by the same neural substrate as observed during awake perception.
An Inhibitor of Mutant IDH1 Delays Growth and Promotes Differentiation of Glioma Cells
Authors: Rohle Dan , Popovici-Muller Janeta , Palaskas Nicolaos , Turcan Sevin , Grommes Christian , Campos Carl , Tsoi Jennifer , Clark Owen , Oldrini Barbara , Komisopoulou Evangelia , Kunii Kaiko , Pedraza Alicia , Schalm Stefanie , Silverman Lee , Miller Alexandra , Wang Fang , Yang Hua , Chen Yue , Kernytsky Andrew , Rosenblum Marc K. , Liu Wei , Biller Scott A. , Su Shinsan M. , Brennan Cameron W. , Chan Timothy A. , Graeber Thomas G. , Yen Katharine E. , Mellinghoff Ingo K.
Published: April 2013

IDHology

Among the most exciting drug targets to emerge from cancer genome sequencing projects are two related metabolic enzymes, isocitrate dehydrogenases 1 and 2 (IDH1, IDH2). Mutations in the
IDH1
and
IDH2
genes are common in certain types of human cancer. Whether inhibition of mutant IDH activity might offer therapeutic benefits is unclear (see the Perspective by

Kim and DeBerardinis

).

F. Wang
et al.

(p.
622
, published online 4 April) isolated a small molecule that selectively inhibits mutant IDH2, describe the structural details of its binding to the mutant enzyme, and show that this compound suppresses the growth of patient-derived leukemia cells harboring the
IDH2
mutation.

Rohle
et al.

(p.
626
, published online 4 April) show that a small molecule inhibitor of IDH1 selectively slows the growth of patient-derived brain tumor cells with the
IDH1
mutation.
Draft Genome Sequence of VIM-2-Producing Multidrug-Resistant Pseudomonas aeruginosa ST175, an Epidemic High-Risk Clone
Authors: Viedma Esther , Juan Carlos , Otero Joaquín R. , Oliver Antonio , Chaves Fernando
Published: April 2013

The VIM-2-producing multidrug-resistant high-risk clone
Pseudomonas aeruginosa
sequence type (ST) 175 was isolated in the setting of a large outbreak in Hospital Universitario 12 de Octubre (Spain) from 2007 to 2010. This strain was resistant to all β-lactams, fluoroquinolones, and aminoglycosides, with the exception of amikacin, and has become an endemic clone in our institution.
Draft Genome Sequence of Dihydroxyacetone-Producing Gluconobacter thailandicus Strain NBRC 3255
Authors: Matsutani Minenosuke , Kawajiri Erika , Yakushi Toshiharu , Adachi Osao , Matsushita Kazunobu
Published: April 2013

Here, we report the draft genome sequence of the acetic acid bacterium
Glucnobacter thailandicus
strain NBRC 3255. The draft genome sequence is composed of 109 contigs in 3,305,227 bp and contains 3,225 protein-coding genes. Two paralogous sets of
sldAB
operons, which are responsible for dihydroxyacetone production from glycerol, were identified.
Juvenile Huntington's disease: a population-based study using the General Practice Research Database
Authors: Douglas Ian , Evans Stephen , Rawlins Michael D , Smeeth Liam , Tabrizi Sarah J , Wexler Nancy S
Published: April 2013

Background

The juvenile form of Huntington's disease (HD) is a rare disorder. There are no population-based estimates of either its incidence or prevalence in any population in the world. The present study was undertaken to estimate the frequency of juvenile HD in the UK and to examine the range of pharmacological treatments used in its management.

Method

The records of individuals under the age of 21 who had recorded diagnoses of HD were retrieved from the General Practice Research Database from 1990 through 2010. From these data estimates of incidence and prevalence were made as well as the specific treatments used in the treatment of its physical and psychological manifestations.

Results

12 incident and 21 prevalent patients with juvenile HD were identified. The 21 prevalent cases included the 12 incident cases. The minimum population-based estimate of incidence is 0.70 (95% CI 0.36 to 1.22) per million patient-years. The minimum estimate of prevalence is 6.77/million (95% CI 5.60 to 8.12) per million patient-years. Patients were most frequently prescribed antidepressants, hypnotics, antipsychotics and treatments for motor abnormalities.

Conclusions

In the UK, juvenile HD is an extremely rare and complex disorder. The prescribing data demonstrate that the clinical management of juvenile HD is undertaken with no formal evidence base for the efficacy or safety of the treatments used. Research into the safety and efficacy of appropriate therapies is urgently required to offset the haphazard nature of prescribing. Multinational collaboration will be necessary to enrol sufficient numbers. Exploratory studies, though, should begin now.
A qualitative study of GP, NP and patient views about the use of rapid streptococcal antigen detection tests (RADTs) in primary care: ‘swamped with sore throats?’
Authors: Leydon Gerry M , McDermott Lisa , Moore Mike , Williamson Ian , Hobbs F D Richard , Lambton Tessa , Cooper Rebecca , Henderson Hugo , Little Paul
Published: April 2013

Objective

To explore patient and healthcare professionals’ (HCP) views of clinical scores and rapid streptococcal antigen detection tests (RADTs) for acute sore throat.

Design

Qualitative semistructured interview study.

Setting

UK primary care.

Participants

General practitioners (GPs), nurse practitioners (NPs) and patients from general practices across Hampshire, Oxfordshire and the West Midlands who were participating in the Primary Care Streptococcal Management (PRISM) study.

Method

Semistructured, face-to-face and phone interviews were conducted with GPs, NPs and patients from general practices across Hampshire, Oxfordshire and the West Midlands.

Results

51 participants took part in the study. Of these, 42 were HCPs (29 GPs and 13 NPs) and 9 were patients. HCPs could see a positive role for RADTs in terms of reassurance, as an educational tool for patients, and for aiding inexperienced practitioners, but also had major concerns about RADT use in clinical practice. Particular concerns included the validity of the tests (the role of other bacteria, and carrier states), the tension and possible disconnect with clinical assessment and intuition, the issues of time and resource use and the potential for medicalisation of self-limiting illness. In contrast, however, experience of using RADTs over time seemed to make some participants more positive about using the tests. Moreover, patients were much more positive about the place of RADTs in providing reassurance and in limiting their antibiotic use.

Conclusions

It is unlikely that RADTs will have a (comfortable) place in clinical practice in the near future until health professionals’ concerns are met, and they have direct experience of using them. The routine use of clinical scoring systems for acute upper respiratory illness also face important barriers related to clinicians’ perceptions of their utility in the face of clinician experience and intuition.
EFFECTS OF HALL CURRENT ON THE FLOW AND HEAT TRANSFER OF A NANOFLUID OVER A STRETCHING SHEET WITH PARTIAL SLIP
Authors: ABD EL-AZIZ MOHAMED
Published: April 2013

The problem of a steady boundary layer MHD slip flow over a stretching sheet in a water-based nanofluid containing different type of nanoparticles: Cu , Al2O3 and Ag has been investigated. An external strong magnetic field is applied perpendicular to the plate and the Hall effect is taken into consideration. The surface of the stretching sheet is assumed to move with a linear velocity and subject to power-law variation of the surface temperature. The governing partial differential equations are transformed into nonlinear ordinary differential equations using a similarity transformation, before being solved numerically by a Runge–Kutta–Fehlberg method with shooting technique. Effects of the physical parameters on the primary velocity, the secondary velocity and the temperature as well as on the wall shear stress and the rate of heat transfer have been presented graphically and discussed in detail. Investigated results indicate that the nanoparticle volume fraction and the slip parameter produce opposite effects on the skin friction coefficients of the primary and secondary flow. Also, the nanoparticle volume fraction and the types of nanoparticles demonstrate a more pronounced influence on the secondary flow than that on the primary flow and temperature distribution.
THERMAL EQUILIBRIUM STATES OF A LINEAR SCALAR QUANTUM FIELD IN STATIONARY SPACE–TIMES
Authors: SANDERS KO
Published: April 2013

The linear scalar quantum field, propagating in a globally hyperbolic space–time, is a relatively simple physical model that allows us to study many aspects in explicit detail. In this review, we focus on the thermal equilibrium (KMS) states of such a field in a stationary space–time. Our presentation draws on several existing sources and aims to give a unified exposition, while weakening certain technical assumptions. In particular we drop all assumptions on the behavior of the time-like Killing field, which is important for physical applications to the exterior region of a stationary black hole.

Our review includes results on the existence and uniqueness of ground and KMS states, as well as an evaluation of the evidence supporting the KMS-condition as a characterization of thermal equilibrium. We draw attention to the poorly understood behavior of the temperature of the quantum field with respect to locality.

If the space–time is standard static, the analysis can be done more explicitly. For compact Cauchy surfaces we consider Gibbs states and their properties. For general Cauchy surfaces we give a detailed justification of the Wick rotation, including the explicit determination of the Killing time dependence of the quasi-free KMS states.
Porphyrin doping of dichloride-bis(5,7-dichloroquinolin-8-olato)tin(IV) complex for electroluminescence
Authors: Janghouri Mohammad , Mohajerani Ezeddin , Amini Mostafa M. , Safari Naser
Published: April 2013

A method for obtaining red emission from an organic-light emitting diode has been developed by dissolving red and yellow dyes in a common solvent and thermally evaporating the mixture in a single furnace. Dichlorido-bis(5,7-dichloroquinolin-8-olato)tin(IV) complex ( Q2SnCl2, Q = 5,7-dichloro-8-hydroxyquinoline) has been synthesized for using as a fluorescent material in organic light-emitting diodes (OLEDs). The electronic states HOMO (Highest Occupied Molecular Orbital)/LUMO (Lowest Occupied Molecular Orbital) energy levels explored by means of cyclic voltammetry measurements. A device with fundamental structure of ITO/PEDOT:PSS (55nm)/PVK (90nm)/ Q2SnCl2/Al (180nm) was fabricated and its electroluminescence performance at various thicknesses of light emitting layer (LEL) of Q2SnCl2is reported. By following this step, an optimal thickness for the doping effect was also identified and explained. Finally a device with fundamental structure of ITO/PEDOT:PSS (55nm)/PVK (90nm)/meso-tetraphenylporphyrin (TPP): Q2SnCl2(75nm)/ Al (180nm) was fabricated and its electroluminescence performance at various concentrations of dye has been investigated. It is shown that this new method is promising candidate for fabrication of low cost OLEDs at more homogeneous layer.
Structural Glycomic Analyses at High Sensitivity: A Decade of Progress
Authors: Alley William R. , Novotny Milos V.
Published: April 2013

The field of glycomics has recently advanced in response to the urgent need for structural characterization and quantification of complex carbohydrates in biologically and medically important applications. The recent success of analytical glycobiology at high sensitivity reflects numerous advances in biomolecular mass spectrometry and its instrumentation, capillary and microchip separation techniques, and microchemical manipulations of carbohydrate reactivity. The multimethodological approach appears to be necessary to gain an in-depth understanding of very complex glycomes in different biological systems.
Nanowire Heterostructures
Authors: Hyun Jerome K. , Zhang Shixiong , Lauhon Lincoln J.
Published: April 2013

The nanoscale diameter and high aspect ratio of nanowires are the foundation of fascinating structure-property relationships derived from confinement, interface effects, and mechanical degrees of freedom. When heterostructures are formed by high-quality growth of dissimilar materials on or within nanowires, the interactions of the low-dimensional components and their interfaces can give rise to electronic, photonic, magnetic, and thermal characteristics that are superior to those of (or unattainable in) planar geometries. This tutorial review provides a brief overview of heterostructures with a semiconductor nanowire as the central component, describes the properties of nanoscale components and interfaces, and distills the advantages that arise from the unique structure-property relationships. A select set of these concepts are further elaborated by highlighting electronic, optoelectronic, and energy-related applications that have successfully exploited these advantages.
The Principles of Experimental Design and Their Application in Sociology
Authors: Jackson Michelle , Cox D.R.
Published: April 2013

In light of an increasing interest in experimental work, we provide a review of some of the general issues involved in the design of experiments and illustrate their relevance to sociology and to other areas of social science of interest to sociologists. We provide both an introduction to the principles of experimental design and examples of influential applications of design for different types of social science research. Our aim is twofold: to provide a foundation in the principles of design that may be useful to those planning experiments and to provide a critical overview of the range of applications of experimental design across the social sciences.
Oral consumption of electrokinetically modified water attenuates muscle damage and improves postexercise recovery
Authors: Borsa Paul A. , Kaiser Kelly L. , Martin Jeffrey S.
Published: April 2013

The purpose of this study was to assess the effects of consuming electrokinetically modified water (EMW) on attenuating muscle damage and improving functional recovery following a single bout of isokinetic resistance exercise. Subjects were randomly assigned to an EMW ( n = 20) or a placebo control ( n = 20) group. Subjects consumed EMW or placebo water daily for 23 days. On day 19 subjects completed an exercise protocol for the biceps brachii to induce muscle damage. The protocol consisted of three sets of 20 repetitions using concentric and eccentric contractions of the elbow flexors. Blood draw and clinical measurements were performed preexercise as well as 24, 48, and 96 h postexercise. Clinical measures included maximal isometric strength, muscle soreness, pain with elbow extension, relaxed elbow angle (RANG), and self-report arm disability. Plasma samples were analyzed to determine concentrations of creatine kinase (CK) and high-sensitivity C-reactive protein (hsCRP). Pain with elbow extension and self-report arm disability were significantly higher in the placebo group compared with the EMW group at 48 h ( P < 0.01) and 96 h ( P < 0.01) after exercise, while RANG was significantly higher in the EMW group compared with placebo at 48 h ( P < 0.01) and 96 h ( P < 0.01) after exercise. Similarly, plasma concentrations for hsCRP and CK were significantly lower in the EMW group compared with placebo at 48 h ( P < 0.05) and 96 h ( P < 0.01) after exercise. Oral consumption of EMW significantly reduced exercise-induced muscle damage and inflammation and improved functional recovery.
The effects of isometric resistance training on stretch reflex induced tremor in the knee extensor muscles
Authors: Durbaba Rade , Cassidy Angela , Budini Francesco , Macaluso Andrea
Published: April 2013

This study examines the effect of 4 wk of high-intensity isometric resistance training on induced tremor in knee extensor muscles. Fourteen healthy volunteers were assigned to either the training group ( n = 7) or the nontraining control group ( n = 7). Induced tremor was assessed by measuring force fluctuations during anisometric contractions against spring loading, whose compliance was varied to allow for preferential activation of the short or long latency stretch reflex components. Effects of high-intensity isometric resistance training on induced tremor was assessed under two contraction conditions: relative force matching, where the relative level of activity was equal for both pre- and post-training sessions, set at 30% maximum voluntary contraction (MVC), and absolute force matching, where the level of activity was set to 30% pretrained MVC. The training group experienced a 26.5% increase in MVC in contrast to the 0.8% for the control group. For relative force-matching contractions, induced tremor amplitude and frequency did not change in either the training or control group. During absolute force-matching contractions, induced tremor amplitude was decreased by 37.5% and 31.6% for the short and long components, respectively, with no accompanying change in frequency, for the training group. No change in either measure was observed in the control group for absolute force-matching contractions. The results are consistent with high-intensity isometric resistance training induced neural changes leading to increased strength, coupled with realignment of stretch reflex automatic gain compensation to the new maximal force output. Also, previous reported reductions in anisometric tremor following strength training may partly be due to changed stretch reflex behavior.
Muscle fascicle strains in human gastrocnemius during backward downhill walking
Authors: Hoffman B. W. , Cresswell A. G. , Carroll T. J. , Lichtwark G. A.
Published: April 2013

Extensive muscle damage can be induced in isolated muscle preparations by performing a small number of stretches during muscle activation. While typically these fiber strains are large and occur over long lengths, the extent of exercise-induced muscle damage (EIMD) observed in humans is normally less even when multiple high-force lengthening actions are performed. This apparent discrepancy may be due to differences in muscle fiber and tendon dynamics in vivo; however, muscle and tendon strains have not been quantified during muscle-damaging exercise in humans. Ultrasound and an infrared motion analysis system were used to measure medial gastrocnemius fascicle length and lower limb kinematics while humans walked backward, downhill for 1 h (inducing muscle damage), and while they walked briefly forward on the flat (inducing no damage). Supramaximal tibial nerve stimulation, ultrasound, and an isokinetic dynamometer were used to quantify the fascicle length-torque relationship pre- and 2 h postexercise. Torque decreased ∼23%, and optimal fascicle length shifted rightward ∼10%, indicating that EIMD occurred during the damage protocol even though medial gastrocnemius fascicle stretch amplitude was relatively small (∼18% of optimal fascicle length) and occurred predominantly within the ascending limb and plateau region of the length-torque curve. Furthermore, tendon contribution to overall muscle-tendon unit stretch was ∼91%. The data suggest the compliant tendon plays a role in attenuating muscle fascicle strain during backward walking in humans, thus minimizing the extent of EIMD. As such, in situ or in vitro mechanisms of muscle damage may not be applicable to EIMD of the human gastrocnemius muscle.
Another Ace up the Sleeve
Authors: Kleinsasser Axel T. , Lindner Karl H.
Published: April 2013

No abstract available
Diesel Exhaust Induces Systemic Lipid Peroxidation and Development of Dysfunctional Pro-Oxidant and Pro-Inflammatory High-Density Lipoprotein
Authors: Yin Fen , Lawal Akeem , Ricks Jerry , Fox Julie R. , Larson Tim , Navab Mohamad , Fogelman Alan M. , Rosenfeld Michael E. , Araujo Jesus A.
Published: April 2013

Objective—

To evaluate whether exposure to air pollutants induces oxidative modifications of plasma lipoproteins, resulting in alteration of the protective capacities of high-density lipoproteins (HDLs).

Approach and Results—

We exposed apolipoprotein E–deficient mice to diesel exhaust (DE) at ≈250 µg/m
3
for 2 weeks, filtered air (FA) for 2 weeks, or DE for 2 weeks, followed by FA for 1 week (DE+FA). DE led to enhanced lipid peroxidation in the brochoalveolar lavage fluid that was accompanied by effects on HDL functionality. HDL antioxidant capacity was assessed by an assay that evaluated the ability of HDL to inhibit low-density lipoprotein oxidation estimated by 2′,7′-dichlorofluorescein fluorescence. HDL from DE-exposed mice exhibited 23 053±2844 relative fluorescence units, higher than FA-exposed mice (10 282±1135 relative fluorescence units,
P
<0.001) but similar to the HDL from DE+FA-exposed mice (22 448±3115 relative fluorescence units). DE effects on HDL antioxidant capacity were negatively correlated with paraoxonase enzymatic activity, but positively correlated with levels of plasma 8-isoprostanes, 12-hydroxyeicosatetraenoic acid, 13-hydroxyoctadecadienoic acid, liver malondialdehyde, and accompanied by perturbed HDL anti-inflammatory capacity and activation of the 5-lipoxygenase pathway in the liver.

Conclusions—

DE emissions induced systemic pro-oxidant effects that led to the development of dysfunctional HDL. This may be one of the mechanisms by which air pollution contributes to enhanced atherosclerosis.
Dietary Carnosine Prevents Early Atherosclerotic Lesion Formation in Apolipoprotein E–Null Mice
Authors: Barski Oleg A. , Xie Zhengzhi , Baba Shahid P. , Sithu Srinivas D. , Agarwal Abhinav , Cai Jian , Bhatnagar Aruni , Srivastava Sanjay
Published: April 2013

Objective—

Atherosclerotic lesions are associated with the accumulation of reactive aldehydes derived from oxidized lipids. Although inhibition of aldehyde metabolism has been shown to exacerbate atherosclerosis and enhance the accumulation of aldehyde-modified proteins in atherosclerotic plaques, no therapeutic interventions have been devised to prevent aldehyde accumulation in atherosclerotic lesions.

Approach and Results—

We examined the efficacy of carnosine, a naturally occurring β-alanyl-histidine dipeptide, in preventing aldehyde toxicity and atherogenesis in apolipoprotein E–null mice. In vitro, carnosine reacted rapidly with lipid peroxidation-derived unsaturated aldehydes. Gas chromatography mass-spectrometry analysis showed that carnosine inhibits the formation of free aldehydes 4-hydroxynonenal and malonaldialdehyde in Cu
2+
-oxidized low-density lipoprotein. Preloading bone marrow–derived macrophages with cell-permeable carnosine analogs reduced 4-hydroxynonenal–induced apoptosis. Oral supplementation with octyl-D-carnosine decreased atherosclerotic lesion formation in aortic valves of apolipoprotein E–null mice and attenuated the accumulation of protein-acrolein, protein-4-hydroxyhexenal, and protein-4-hydroxynonenal adducts in atherosclerotic lesions, whereas urinary excretion of aldehydes as carnosine conjugates was increased.

Conclusions—

The results of this study suggest that carnosine inhibits atherogenesis by facilitating aldehyde removal from atherosclerotic lesions. Endogenous levels of carnosine may be important determinants of atherosclerotic lesion formation, and treatment with carnosine or related peptides could be a useful therapy for the prevention or the treatment of atherosclerosis.
Pulmonary Vein Isolation Using a Visually Guided Laser Balloon Catheter
Authors: Dukkipati Srinivas R. , Kuck Karl-Heinz , Neuzil Petr , Woollett Ian , Kautzner Josef , McElderry H. Thomas , Schmidt Boris , Gerstenfeld Edward P. , Doshi Shephal K. , Horton Rodney , Metzner Andreas , d’Avila Andre , Ruskin Jeremy N. , Natale Andrea , Reddy Vivek Y.
Published: April 2013

Background—

Because of the technical difficulty with achieving pulmonary vein (PV) isolation in the treatment of patients with paroxysmal atrial fibrillation, novel catheter designs to facilitate the procedure are in development. A visually guided laser ablation (VGLA) catheter was designed to allow the operator to directly visualize target tissue for ablation and then deliver laser energy to perform point-to-point circumferential ablation. Single-center studies have demonstrated favorable safety and efficacy. We sought to determine the multicenter feasibility, efficacy, and safety of performing PV isolation using the VGLA catheter.

Methods and Results—

This study includes the first 200 paroxysmal atrial fibrillation patients treated with the VGLA catheter (33 operators, 15 centers). After transseptal puncture, the VGLA catheter was used to perform PV isolation. Electric isolation was assessed using a circular mapping catheter. Using the VGLA catheter, 98.8% (95% confidence interval, 97.8%–99.5%) of targeted PVs were isolated using a mean of 1.07 catheters per patient. Fluoroscopy and procedure times were 31±21 (mean±SD) and 200±54 minutes, respectively, and improved with operator experience. There were no instances of stroke, transient ischemic attack, atrioesophageal fistulas, or significant PV stenosis. There was a 2% incidence of cardiac tamponade and a 2.5% incidence of phrenic nerve palsy. At 12 months, the drug-free rate of freedom from atrial arrhythmias after 1 or 2 procedures was 60.2% (95% confidence interval, 52.7%–67.4%).

Conclusions—

In this multicenter experience of the first 200 patients treated with the VGLA catheter, PV isolation can be achieved in virtually all patients using a single VGLA catheter with an efficacy similar to radiofrequency ablation.
Chronic Pain Syndromes After Ischemic Stroke
Authors: O’Donnell Martin J. , Diener Hans-Christoph , Sacco Ralph L. , Panju Akbar A. , Vinisko Richard , Yusuf Salim
Published: April 2013

Background and Purpose—

Chronic pain syndromes are reported to be common after stroke, but most previous epidemiological studies have generally included small cohorts of patients with relatively short-term follow-up. In a large cohort with ischemic stroke (Prevention Regimen for Effectively avoiding Second Stroke [PRoFESS] trial), we determined the prevalence, risk factors, and clinical consequence of new poststroke pain syndromes.

Methods—

Within the PRoFESS trial (mean follow-up 2.5 years), a standardized chronic pain questionnaire was administered (at the penultimate follow-up visit) to all participants who reported chronic pain since their stroke and did not have a history of chronic pain before their index stroke. Multivariable logistic regression analyses were used to determine risk factors for poststroke pain (and pain subtypes), and the association between poststroke pain and cognitive (≥3 reduction in Mini-Mental State Examination score) and functional decline (≥1 increase in m-Rankin).

Results—

In total, 15 754 participants were included; of which 1665 participants (10.6%) reported new chronic poststroke pain, and included 431 participants (2.7%) with central poststroke pain, 238 (1.5%) with peripheral neuropathic pain, 208 (1.3%) with pain from spasticity, and 136 participants (0.9%) with pain from shoulder subluxation. More than 1 pain subtype was reported in 86 participants (0.6%). Predictors of poststroke pain included increased stroke severity, female sex, alcohol intake, statin use, depressive symptoms, diabetes mellitus, antithrombotic regimen, and peripheral vascular disease. A new chronic pain syndrome was associated with greater dependence (odds ratio, 2.16; 95% confidence interval, 1.82–2.56). Peripheral neuropathy and pain from spasticity/shoulder subluxation were associated with cognitive decline.

Conclusions—

Chronic pain syndromes are common after ischemic stroke and are associated with increased functional dependence and cognitive decline.
Airway management using a supraglottic airway device without endotracheal intubation for positive ventilation of anaesthetized rats
Authors: Cheong S H , Lee J H , Kim M H , Cho K R , Lim S H , Lee K M , Park M Y , Yang Y I , Kim D K , Choi C S
Published: April 2013

Endotracheal intubation is often necessary for positive pressure ventilation of rats during open thoracic surgery. Since endotracheal intubation in rats is technically difficult and is associated with numerous complications, many techniques using various devices have been described in the scientific literature. In this study, we compared the effectiveness of airway management of a home-made supraglottic airway device (SAD), which is cheap to fabricate and easy to place with that of an endotracheal intubation tube in enflurane-anaesthetized rats. Twenty male Sprague-Dawley rats (200–300 g) were randomly assigned to two equal groups for positive pressure mechanical ventilation using either the SAD or an endotracheal intubation tube. The carotid artery of each rat was cannulated for continuous blood pressure measurements and obtaining blood samples for determination of oxygen tension, carbon dioxide tension, and blood acidity before, during and after SAD placement or endotracheal intubation. Proper placement of the SAD was confirmed by observing chest wall movements that coincided with the operation of the mechanical ventilator. No complications and adverse events were encountered in the rats in which the SAD was placed, during SAD placement and immediate removal, during their mechanical ventilation through the SAD, and one week after SAD removal. From the results of blood gas analyses, we conclude that anaesthetized rats can be successfully ventilated using an SAD for open thoracic surgery.
The preliminary exploration of 64-slice volume computed tomography in the accurate measurement of pleural effusion
Authors: Guo Zhi-Jun , Lin Qiang , Liu Hai-Tao , Lu Jun-Ying , Zeng Yan-Hong , Meng Fan-Jie , Cao Bin , Zi Xue-Rong , Han Shu-Ming , Zhang Yu-Huan
Published: April 2013

Background

Using computed tomography (CT) to rapidly and accurately quantify pleural effusion volume benefits medical and scientific research. However, the precise volume of pleural effusions still involves many challenges and currently does not have a recognized accurate measuring.

Purpose

To explore the feasibility of using 64-slice CT volume-rendering technology to accurately measure pleural fluid volume and to then analyze the correlation between the volume of the free pleural effusion and the different diameters of the pleural effusion.

Material and Methods

The 64-slice CT volume-rendering technique was used to measure and analyze three parts. First, the fluid volume of a self-made thoracic model was measured and compared with the actual injected volume. Second, the pleural effusion volume was measured before and after pleural fluid drainage in 25 patients, and the volume reduction was compared with the actual volume of the liquid extract. Finally, the free pleural effusion volume was measured in 26 patients to analyze the correlation between it and the diameter of the effusion, which was then used to calculate the regression equation.

Results

After using the 64-slice CT volume-rendering technique to measure the fluid volume of the self-made thoracic model, the results were compared with the actual injection volume. No significant differences were found, P = 0.836. For the 25 patients with drained pleural effusions, the comparison of the reduction volume with the actual volume of the liquid extract revealed no significant differences, P = 0.989. The following linear regression equation was used to compare the pleural effusion volume (V) (measured by the CT volume-rendering technique) with the pleural effusion greatest depth (d): V = 158.16 × d − 116.01 (r = 0.91, P = 0.000). The following linear regression was used to compare the volume with the product of the pleural effusion diameters (l × h × d): V = 0.56 × (l × h × d) + 39.44 (r = 0.92, P = 0.000).

Conclusion

The 64-slice CT volume-rendering technique can accurately measure the volume in pleural effusion patients, and a linear regression equation can be used to estimate the volume of the free pleural effusion.
Measurement of the uniaxial mechanical properties of rat brains infected by Plasmodium berghei ANKA
Authors: Karimi Alireza , Navidbakhsh Mahdi , Motevalli Haghi Afsaneh , Faghihi Shahab
Published: April 2013

Degenerative and demyelinating diseases are known to alter the mechanical properties of brain tissue. While few studies have characterized these biomechanical changes, it is clear that accurate characterization of the mechanical properties of diseased brain tissue could be a substantial asset to neuronavigation and surgery simulation through haptic devices. In this study, samples of brain tissue from rats infected with Plasmodium berghei ANKA, an African murine malaria parasite, are evaluated using a uniaxial tensile test machine. Infected brains having different levels of parasitemia are mounted on the testing machine and extended until failure of the tissue. The stress–strain curve of each sample is obtained and compared to healthy rat brain tissue. Young’s modulus of each sample is extracted from the Hookean part of the stress–strain diagram. Young’s modulus of rats’ brain shows considerable difference among the samples having various levels of parasitemia compared with the controls. For instance, the brains with 0% (control), 1.5%, and 9% parasitemia showed a Young’s modulus of 46.15, 54.54, and 266.67 kPa, respectively. This suggests sequestration of the stiffened and less deformable parasitized red blood cells in the brain microvasculature.
Women’s Experiences of Coping With Pregnancy Termination for Fetal Abnormality
Authors: Lafarge Caroline , Mitchell Kathryn , Fox Pauline
Published: April 2013

Pregnancy termination for fetal abnormality (TFA) can have significant psychological consequences. Most previous research has been focused on measuring the psychological outcomes of TFA, and little is known about the coping strategies involved. In this article, we report on women’s coping strategies used during and after the procedure. Our account is based on experiences of 27 women who completed an online survey. We analyzed the data using interpretative phenomenological analysis. Coping comprised four structures, consistent across time points: support, acceptance, avoidance, and meaning attribution. Women mostly used adaptive coping strategies but reported inadequacies in aftercare, which challenged their resources. The study’s findings indicate the need to provide sensitive, nondirective care rooted in the acknowledgment of the unique nature of TFA. Enabling women to reciprocate for emotional support, promoting adaptive coping strategies, highlighting the potential value of spending time with the baby, and providing long-term support (including during subsequent pregnancies) might promote psychological adjustment to TFA.
Association study of OPRM1 polymorphisms with Schizophrenia in Han Chinese population
Authors: Ding Saidan , Chen Bicheng , Zheng Yong , Lu Qin , Liu Leping , Zhuge Qǐ-Chuan
Published: April 2013

Background

The expression of μ-opioid receptor has important role in cognitive dysfunction in Schizophrenia (SZ). The results of studies about the association of polymorphisms of μ-opioid receptor gene (OPRM1) with SZ were inconsistent.

Methods

We conducted a case–control study to investigate the genetic association between OPRM1 polymorphisms and SZ among the Han chinese population. 264 SZ patients and 264 age-matched control subjects were recruited. Four SNPs of OPRM1 were successfully genotyped by using PCR-RFLP.

Results

Of four polymorphisms, rs1799971 and rs2075572 were shown to associate with SZ. Compared with the A allele of rs1799971 and C allele of rs2075572, the G allele of rs1799971 and rs2075572 was associated with an almost 0.46-fold risk (OR = 0.46, 95% CI: 0.357-0.59, P < 0.01) and 0.7-fold risk (OR = 0.707, 95% CI: 0.534-0.937, P = 0.015) of the occurrence of SZ,. When subjects were divided by gender, rs1799971 remained significant difference only in males (OR = 0.309, 95% CI: 0.218-0.439 for G allele, P < 0.01), and rs2075572 only in females (OR = 0.399, 95% CI: 0.246-0.648 for G allele, P < 0.01). In secondary analysis with subsets of patients, the G allele of rs1799971 (compared to the A allele) was associated with a decreased risk of all patients and male patients with apathy symptoms (OR = 0.086, 95% CI: 0.048-0.151, P = 0.01; OR = 0.083, 95% CI: 0.045-0.153, P < 0.01), and the G allele of rs2075572 (compared to the C allele) was associated with a decreased risk of all patients and female patients with positive family history (OR = 0.468, 95% CI: 0.309-0.71, P < 0.01; OR = 0.34, 95% CI: 0.195-0.593, P < 0.01). In addition, haplotype analysis revealed that two SNP haplotypes (A-C-C-G and G-C-C-A) were associated with decreased risks of SZ (P < 0.01). The other two (G-C-C-G and G-G-C-G) with increased risks of SZ (P < 0.01).

Conclusions

The present study demonstrated for the first time that the OPRM1 polymorphism may be a risk factor for schizophrenia in the Han Chinese. Further studies are needed to give a global view of this polymorphism in pathogenesis of schizophrenia in a large-scale sample, family-based association design or well-defined subgroups of schizophrenia.
Application of Structural Equation Modeling in EFL Testing: A Report of Two Iranian Studies
Authors: Alavi Mohammad , Ghaemi Hamed
Published: April 2013

Structural equation modeling (SEM) is a statistical method used for testing and estimating causal relations using a combination of statistical data and qualitative causal assumptions. This paper reports two studies done by the researchers through the application of SEM. In the first study the relationship between EFL learners' affective constructs and their English achievement was assessed using SEM. Since both Structural coefficient and Goodness of fit are high, we conclude that not only is the model accepted but also the relationship between EFL learners' affective constructs and their English achievement is statistically significant. The second study investigated the relationship between Affective constructs and Study Process of EFL learners through the application of SEM. In this study the Goodness of Fit Index (GFI) turned out to be 0.99. Again like the previous study, since the Goodness of Fit Index (GFI) and structural coefficient are high, we conclude that there is a statistically strong relationship between affective constructs and study process of EFL learners.