bluuebunny/crossref_metadata_2025 huggingface dataset:
Productive Human Immunodeficiency Virus Type 1 Infection in Peripheral Blood Predominantly Takes Place in CD4/CD8 Double-Negative T Lymphocytes
Authors: Kaiser Philipp , Joos Beda , Niederöst Barbara , Weber Rainer , Günthard Huldrych F. , Fischer Marek
Published: July 2007

Human immunodeficiency virus type 1 (HIV-1) transcription is subject to substantial fluctuation during the viral life cycle. Due to the low frequencies of HIV-1-infected cells, and because latently and productively infected cells collocate in vivo, little quantitative knowledge has been attained about the range of in vivo HIV-1 transcription in peripheral blood mononuclear cells (PBMC). By combining cell sorting, terminal dilution of intact cells, and highly sensitive, patient-specific PCR assays, we divided PBMC obtained from HIV-1-infected patients according to their degree of viral transcription activity and their cellular phenotype. Regardless of a patient's treatment status, the bulk of infected cells exhibited a CD4+phenotype but transcribed HIV-1 provirus at low levels, presumably insufficient for virion production. Furthermore, the expression of activation markers on the surface of these CD4+T lymphocytes showed little or no association with enhancement of viral transcription. In contrast, HIV-infected T lymphocytes of a CD4−/CD8−phenotype, occurring exclusively in untreated patients, exhibited elevated viral transcription rates. This cell type harbored a substantial proportion of all HIV RNA+cells and intracellular viral RNAs and the majority of cell-associated virus particles. In conjunction with the observation that the HIV quasispecies in CD4+and CD4−/CD8−T cells were phylogenetically closely related, these findings provide evidence that CD4 expression is downmodulated during the transition to productive infection in vivo. The abundance of viral RNA in CD4−/CD8−T cells from viremic patients and the almost complete absence of viral DNA and RNA in this cell type during antiretroviral treatment identify HIV+CD4−/CD8 T cells as the major cell type harboring productive infection in peripheral blood.
Fusion of Cyclophilin A to Fv1 Enables Cyclosporine-Sensitive Restriction of Human and Feline Immunodeficiency Viruses
Authors: Schaller Torsten , Ylinen Laura M. J. , Webb Benjamin L. J. , Singh Shalene , Towers Greg J.
Published: July 2007

TRIM5α is a potent intracellular antiviral restriction factor governing species-specific retroviral replication. In the New World species owl monkey the coding region for the viral binding B30.2 domain of TRIM5α has been replaced by a cyclophilin A (CypA) pseudogene by retrotransposition. The resultant TRIM5-CypA fusion protein restricts human immunodeficiency virus type 1 (HIV-1), as well as feline immunodeficiency virus (FIV), by recruitment of the CypA domain to the incoming viral capsids. Infectivity is rescued by agents such as cyclosporine that disrupt CypA binding to its substrates. Mice encode an antiviral restriction factor called Fv1 (for Friend virus susceptibility gene 1), which is active against murine leukemia virus and related to endogenous gag sequences. Here we show that fusing CypA to Fv1 generates a restriction factor with the antiviral specificity of TRIMCyp but the antiviral properties of Fv1. Like TRIMCyp, Fv1-Cyp restricts HIV-1 and FIV and is sensitive to inhibition by cyclosporine. TRIM5α is known to have a short half-life and block infectivity before viral reverse transcription. We show that Fv1-Cyp has a long half-life and blocks after reverse transcription, suggesting that its longer half-life gives the restricted virus the opportunity to synthesize DNA, leading to a later block to infection. This notion is supported by the observation that infectivity of Fv1-Cyp restricted virus can be rescued by cyclosporine for several hours after infection, whereas virus restricted by TRIMCyp is terminally restricted after around 40 min. Intriguingly, the Fv1-Cyp-restricted HIV-1 generates closed circular viral DNA, suggesting that the restricted virus complex enters the nucleus.
Epochal Evolution of GGII.4 Norovirus Capsid Proteins from 1995 to 2006
Authors: Siebenga J. Joukje , Vennema Harry , Renckens Bernadet , de Bruin Erwin , van der Veer Bas , Siezen Roland J. , Koopmans Marion
Published: July 2007

Noroviruses are the causative agents of the majority of viral gastroenteritis outbreaks in humans. During the past 15 years, noroviruses of genotype GGII.4 have caused four epidemic seasons of viral gastroenteritis, during which four novel variants (termed epidemic variants) emerged and displaced the resident viruses. In order to understand the mechanisms and biological advantages of these epidemic variants, we studied the genetic changes in the capsid proteins of GGII.4 strains over this period. A representative sample was drawn from 574 GGII.4 outbreak strains collected over 15 years of systematic surveillance in The Netherlands, and capsid genes were sequenced for a total of 26 strains. The three-dimensional structure was predicted by homology modeling, using the Norwalk virus (Hu/NoV/GGI.1/Norwalk/1968/US) capsid as a reference. The highly significant preferential accumulation and fixation of mutations (nucleotide and amino acid) in the protruding part of the capsid protein provided strong evidence for the occurrence of genetic drift and selection. Although subsequent new epidemic variants differed by up to 25 amino acid mutations, consistent changes were observed in only five positions. Phylogenetic analyses showed that each variant descended from its chronologic predecessor, with the exception of the 2006b variant, which is more closely related to the 2002 variant than to the 2004 variant. The consistent association between the observed genetic findings and changes in epidemiology leads to the conclusion that population immunity plays a role in the epochal evolution of GGII.4 norovirus strains.
APPROXIMATIONS OF SINGULAR VERTEX COUPLINGS IN QUANTUM GRAPHS
Authors: EXNER PAVEL , TUREK ONDŘEJ
Published: July 2007

We discuss approximations of the vertex coupling on a star-shaped quantum graph of n edges in the singular case when the wave functions are not continuous at the vertex and no edge-permutation symmetry is present. It is shown that the Cheon–Shigehara technique using δ interactions with nonlinearly scaled couplings yields a 2n-parameter family of boundary conditions in the sense of norm resolvent topology. Moreover, using graphs with additional edges, one can approximate the [Formula: see text]-parameter family of all time-reversal invariant couplings.
ON THE EIGENVALUES OF THE LAPLACIAN FOR LEFT-INVARIANT RIEMANNIAN METRICS ON S3
Authors: MANGASULI ANANDATEERTHA
Published: July 2007

We show that if the Ricci curvature of a left-invariant metric g on S3 is greater than that of the standard metric g0, then the eigenvalues of Δg are greater than the corresponding eigenvalues of Δgo.
DYNAMIC HOLOGRAPHIC IMAGING USING PHOTOREFRACTIVE POLYMERS BASED ON A BORONATE-DERIVATIVE NONLINEAR CHROMOPHORE
Authors: MALDONADO J. L. , RAMOS-ORTÍZ G. , BARBOSA-GARCÍA O. , MENESES-NAVA M. A. , MÁRQUEZ L. , OLMOS-LÓPEZ M. , REYES H. , MUÑOZ B. , FARFÁN N.
Published: July 2007

We report dynamic holographic imaging with organic photorefractive polymer composites, doped with the electro-optic chromophore (2-(p-chlorophenyl)-(3′-nitrobenzo[d])-(4′′-methoxybenzo[h])-1,3-dioxa-6-aza-2-boracyclonon-6-ene, a push-pull molecule derived from a new class of boronates. The composites are based on the photoconductor poly(9-vinylcarbazole) (PVK) as the polymer matrix, and 9-ethylcarbazole (ECZ) as the plasticizer, with the fullerene C 60 as sensitizer. A tilted four-wave mixing geometry was used to record and reconstruct two-dimensional test objects, using a 10 mW He – Ne laser (632.8 nm). The recording response time was less than one second for a light intensity of ≈350 mW/cm 2 in each writing beam. The erasing time had a similar value. These composites have been used for over one year with no appreciable signs of degradation or crystallization.
PRESSURE COMPARISON BETWEEN THE SPHERICAL CELLULAR MODEL AND THE THOMAS-FERMI MODEL
Authors: BAKER GEORGE A.
Published: July 2007

The widely used Thomas Fermi model always produces pressure which is less than or equal to that of the ideal Fermi gas. On the other hand the spherical cellular model, in certain regions of the temperature-density plane, can produce pressures which are greater than that of the ideal gas. This phenomenon is investigated.
QUASIEXCITONS IN PHOTOLUMINESCENCE OF INCOMPRESSIBLE QUANTUM LIQUIDS
Authors: WÓJS A. , GŁADYSIEWICZ A. , QUINN J. J.
Published: July 2007

The problem of a trion (charged exciton) immersed in an incompressible quantum liquid formed by two-dimensional electrons in a high magnetic field is studied theoretically by combining the composite fermion model and exact numerical diagonalization. Laughlin correlation of the trion with the surrounding electrons is shown to lead to the formation of a family of novel many-body excitations called "quasiexcitons" (QXs). The residual charge of the most stable QX can be either zero or the fractional quantum ±e/3, depending on the presence of negative or positive Laughlin quasiparticles in the electron liquid (controlled by the Landau level filling factor ν), but also on the width of the quantum well, Zeeman spin splitting, etc. The prediction of the magnetic-field driven transition from negative to positive QXs is argued to explain the recently observed minute discontinuity in the photoluminescence spectra of sufficiently wide (w ≥ 20 nm ) asymmetric GaAs quantum wells at ν = 1/3. Conversely, the observed discontinuity is hence indirectly linked to the emergence of a fractional charge quantum in the electron liquid.
THE CONCEPT OF CORRELATED DENSITY AND ITS APPLICATION
Authors: MORAWETZ KLAUS , LIPAVSKÝ PAVEL , KOLÁČEK JAN , BRANDT ERNST HELMUT , SCHREIBER MICHAEL
Published: July 2007

The correlated density appears in many physical systems ranging from dense interacting gases up to Fermi liquids which develop a coherent state at low temperatures, the superconductivity. One consequence of the correlated density is the Bernoulli potential in superconductors which compensates forces from dielectric currents. This Bernoulli potential allows to access material parameters. Though within the surface potential these contributions are largely canceled, the bulk measurements with NMR can access this potential. Recent experiments are explained and new ones suggested. The underlying quantum statistical theory in nonequilibrium is the nonlocal kinetic theory developed earlier.
CONDENSED MATTER PHYSICS OF BIOMOLECULE SYSTEMS IN A DIFFERENTIAL GEOMETRIC FRAMEWORK
Authors: BOHR HENRIK , IPSEN JOHN H. , MARKVORSEN STEEN
Published: July 2007

In this contribution biomolecular systems are analyzed in a framework of differential geometry in order to derive important condensed matter physics information. In the first section lipid bi-layer membranes are examined with respect to statistical properties and topology, e.g. a relation between vesicle formation and the proliferation of genus number. In the second section differential geometric methods are used for analyzing the surface structure of proteins and thereby understanding catalytic properties of larger proteins.
STUDY OF WRIST POSTURE, LOADING AND REPETITIVE MOTION AS RISK FACTORS FOR DEVELOPING CARPAL TUNNEL SYNDROME
Authors: Fung B. K. K. , Chan K. Y. , Lam L. Y. , Cheung S. Y. , Choy N. K. , Chu K. W. , Chung L. Y. , Liu W. W. , Tai K. C. , Yung S. Y. , Yip S. L.
Published: July 2007

Occupational risk factors of carpal tunnel syndrome (CTS) are popular current research targets, with main emphasis put on wrist posture and dynamics. In this study, we do not intend to pinpoint individual occupations, but aim to identify high risk wrist postures and actions which may occur across various occupations. It is hoped that prevention can thus be instituted in a general population by directing at the particular causative wrist actions rather than exclusively targeting isolated occupations. We performed a case-control study with 166 cases and 111 controls recruited from different hospitals in Hong Kong in 2004. All cases and controls completed the survey on their general health condition, smoking status, wrist posture and motion as well as psychosocial status at the time of diagnosis of CTS. Frequent flexion OR = 4.436 (95% CI: 1.833–10.734), frequent extension OR = 2.691 (95% CI: 1.106–6.547) of the wrist were found to be associated with CTS. Frequent sustained forceful motion of the wrist OR = 2.588 (95% CI: 1.144–5.851) was also found to be associated with CTS. Neutral wrist position and repetitive wrist motion were not associated with CTS. Adjustment was made for age, sex, BMI, smoking and psychosocial stress. Our study confirms that frequent flexion, extension and sustained force of the wrist increase the risk of developing CTS.
HOMOGENEOUS HYPERBOLIC EQUATIONS WITH COEFFICIENTS DEPENDING ON ONE SPACE VARIABLE
Authors: SPAGNOLO SERGIO , TAGLIALATELA GIOVANNI
Published: July 2007

We investigate the Cauchy problem for homogeneous equations of order m in the (t,x)-plane, with coefficients depending only on x. Assuming that the characteristic roots satisfy the condition [Formula: see text] we succeed in constructing a smooth symmetrizer which behaves like a diagonal matrix: this allows us to prove the well-posedness in [Formula: see text].
TGF-Beta1 Release by Volatile Anesthetics Mediates Protection against Renal Proximal Tubule Cell Necrosis
Authors: Lee H. Thomas , Kim Mihwa , Kim Jeehee , Kim Nala , Emala Charles W.
Published: July 2007

Background/Aims:We have previously demonstrated that clinically utilized volatile anesthetics protect against renal ischemia reperfusion injury in rats in vivo and reduce necrosis in vitro via activation of ERK and Akt and by upregulating HSP70. In this study, we further deciphered the upstream cellular signaling mechanism(s) of volatile anesthetic-mediated antinecrotic effects in vitro. We hypothesized that volatile anesthetics perturb the structure of the plasma membrane lipid bilayer, causing externalization of phosphatidylserine (PS) to the outer surface on renal tubule cells leading to the increased generation of transforming growth factor-β1 (TGF-β1), a cytokine with antinecrotic properties. Methods and Results: In human proximal tubule (HK-2) cell culture, 16-hour exposure to volatile anesthetics (isoflurane, halothane, sevoflurane) caused membrane externalization of PS detected by positive annexin-V staining and increased the release of TGF-β1 into the cell culture media. Exogenous TGF-β1 induced protection and neutralizing TGF-β1 antibody prevented the cytoprotection by volatile anesthetics against hydrogen peroxide-induced HK-2 cell necrosis. Conclusions: Volatile anesthetics induce a cytoprotective signaling cascade in proximal tubule cells via membrane externalization of PS initiating TGF-β1-mediated cytoprotection.
Effect of Sarpogrelate, a 5-HT2A Antagonist, on Platelet Aggregation in Patients with Ischemic Stroke: Clinical-Pharmacological Dose-Response Study
Authors: Uchiyama Shinichiro , Ozaki Yukio , Satoh Kaneo , Kondo Kazuoki , Nishimaru Katsuya
Published: July 2007

Background and Purpose: It is widely accepted that antiplatelet therapy is effective for secondary prevention of atherosclerotic vascular diseases. We performed a double-blind, controlled clinical-pharmacological study to investigate the antiplatelet efficacy of sarpogrelate, a selective 5-hydroxytryptamine (5-HT2A) receptor antagonist, in patients with ischemic stroke, using a new assessment system employing combinations of 5-HT and epinephrine as agonists. Methods: Forty-seven patients with ischemic stroke were randomly assigned to three groups: 15 patients received 25 mg sarpogrelate (group L), 16 patients received 50 mg (group M), and 15 patients received 100 mg (group H) orally, three times daily for 7 days. The effect was expressed as maximum intensity of platelet aggregation on the last day of medication. Two combinations of agonists, 0.5 µmol/l 5-HT plus 3 µmol/l epinephrine, and 1 µmol/l 5-HT plus 3 µmol/l epinephrine, were used to induce platelet aggregation. Results: With both combinations of agonists, sarpogrelate treatment inhibited platelet aggregation dose-dependently (p < 0.025, Jonckheere test). In multiple-group comparison, the effect in group H was greater than that in group L or M (p < 0.025, Wilcoxon rank-sum test). Conclusion: Sarpogrelate treatment inhibited platelet aggregation dose-dependently in patients with ischemic stroke, as judged by a new assessment system employing combinations of 5-HT and epinephrine as agonists.
The Effect of Mild Hyperuricemia on Urinary Transforming Growth Factor Beta and the Progression of Chronic Kidney Disease
Authors: Talaat Khaled M. , El-Sheikh Amira R.
Published: July 2007

Although mild hyperuricemia is common in patients with renal disease, it has usually been considered a marker of reduced nephron mass rather than a risk factor for progression of kidney disease. On the other hand, experiments in a rat model demonstrated important deleterious effects of mild hyperuricemia on several aspects of renal structure and function. In the present investigation, the impact of the discontinuation of allopurinol therapy on the control of hypertension and the rate of progression of chronic kidney disease was considered. The present work involved 50 patients, suffering from stage 3 and 4 chronic kidney disease. All of them were on chronic allopurinol therapy for the treatment of mild hyperuricemia. Their blood pressure, serum creatinine and uric acid levels were followed for 12 months following allopurinol withdrawal. Urinary transforming growth factor beta-1 (TGF-β1) was assayed by a solid-phase enzyme-linked immunosorbent assay. After allopurinol withdrawal, significant worsening of hypertension, significant acceleration of the rate of loss of kidney function and a significant increase in the urinary excretion of TGF-β1 were observed in the group of patients who were not receiving pharmacological blockers of the renin-angiotensin system. In conclusion, asymptomatic hyperuricemia has a deleterious effect on the progression of chronic kidney disease and the control of hypertension. This effect was blocked by treatment with renin-angiotensin system blockers.
Noninvasive Ventilation Using a Mouthpiece in Patients with Chronic Obstructive Pulmonary Disease and Acute Respiratory Failure
Authors: Glerant J.C. , Rose D. , Oltean V. , Dayen C. , Mayeux I. , Jounieaux V.
Published: July 2007

Background: Noninvasive positive pressure ventilation (NPPV) delivered via a mouthpiece (mNPPV) has been successfully used in stable chronic restrictive respiratory insufficiency, but not in patients with chronic obstructive pulmonary disease (COPD) and acute respiratory failure (ARF). Objectives: The purpose of this matched case-control study was to compare the usefulness of mNPPV to noninvasive ventilation using a nasal or oronasal mask (nNPPV) or standard medical treatment (SMT) in COPD patients with ARF. Methods: Twenty-nine patients receiving mNPPV were matched with 29 patients receiving nNPPV and 29 patients receiving SMT regarding age, SAPSII, admission PaCO2 and pH. Results: In the mNPPV group, admission PaCO2 and pH were 78.6 ± 12 mm Hg and 7.30 ± 0.04, respectively. mNPPV and nNPPV avoided the need for endotracheal intubation in 27 and 25 patients, respectively (nonsignificant) whereas SMT resulted in a higher mechanical ventilation rate (13 patients). At the end of the treatment protocol, PaCO2 was lower in the mNPPV group (62.2 ± 9.6 mm Hg) than in the SMT group (72.4 ± 20.4 mm Hg, p < 0.018) leading to a significantly higher pH. No significant differences were observed between the mNPPV and nNPPV groups. Conclusions: In case of moderate respiratory acidosis, noninvasive ventilation using a mouthpiece significantly reduces the endotracheal intubation rate in comparison with SMT and therefore appears to be a second-line alternative to noninvasive ventilation delivered via a mask, especially when poorly tolerated.
Manufacturing Processes and Properties of Copper—Graphite Composites Produced by High Frequency Induction Heating Sintering
Authors: Dewidar Montasser M. , Lim Jae-Kyoo
Published: July 2007

In the present article, a study was made of copper/graphite powders and sintered compacts for industrial applications. The sintering behavior and mechanical properties of copper/graphite composite produced by high frequency induction heated sintering (HFIHS) as a novel sintering technique were studied. HFIHS allows very quick densification to near theoretical density of the composite. The copper was modified by addition of 2.5—15 wt.% graphite. A high dense product (97%) could be obtained within 3 min under simultaneous application of 60 MPa pressure. The wear testing was carried out using a pin-on-ring tribometer. The wear resistance increases with increasing the addition of graphite. The weight loss increases with both sliding distance and applied load. Metallographic investigation was carried out using both optical and scanning electron microscopy. For comparison, parallel compacts of pure copper were made under the same consolidation processing applied for copper—graphite composites.
`Healing the Scars of History': Projects, Skills and Field Strategies in Institutional Entrepreneurship
Authors: Perkmann Markus , Spicer André
Published: July 2007

We explore what institutional entrepreneurs do to propagate new organizational forms. Our findings are derived from a longitudinal study of the `Euroregion', an organizational form used by local authorities situated close to European borders for co-ordinating policies across borders. We find that the institutional entrepreneurs behind the Euroregion engaged in several types of institution-building projects, with a changing focus over time. While the initial emphasis was on interactional projects, this was followed by a focus on technical projects and finally cultural projects. The skills that the institutional entrepreneurs deployed changed accordingly. While in a first phase, predominantly political skills were used, later, analytical skills and finally cultural skills were added. Furthermore, the institutional entrepreneurs propagated the organizational form by switching their institution-building projects between different fields. We interpret these findings by outlining a process theory of institutional entrepreneurship that conceptualizes the institutional entrepreneur in light of its development as an innovating organization.
A comparison of radiographic signs of pulmonary inflammation during ECMO between silicon and poly-methyl pentene oxygenators
Authors: Khoshbin Espeed , Dux Anthony EW , Killer Hilliary , Sosnowski Andrzej W , Firmin Richard K , Peek Giles J
Published: July 2007

Introduction: The inflammatory response caused by extracorporeal membrane oxygenation (ECMO) is clearly visible within the first 24 h of cannulation. The inflammatory process affects all areas of the lung, even areas previously spared by the primary disease. Objective: To compare the change in the radiographic signs of inflammatory response to ECMO between poly-methyl pentene and silicon oxygenators. Study design: Retrospective review of neonates and adults pre- and post-replacement of silicon oxygenators with poly-methyl pentene devices. Data were collected from Extracorporeal Life Support Organisation (ELSO) registry forms and patient records. Results were analysed by quantitative and semi-quantitative methods. Results: There was a significant reduction in the radiographic signs of inflammatory response to ECMO, and a reduction in the time taken to revert to pre-ECMO state in the neonatal poly-methyl pentene group compared to silicon. However, there was no significant reduction in the duration of ECMO runs and the percentage survival between these groups in the neonates. In adults, there was no difference in severity of radiographic signs between groups. However, the inflammatory changes were relatively delayed in the adult poly-methyl pentene group. Conclusion: Poly-methyl pentene (Medos) oxygenators have reduced the host's response phenomenon `white out' in neonates, and caused a delayed response in adults. This is most likely a consequence of smaller blood contact surface area combined with the effect of heparin coating of the oxygenator membrane. However, recovery was not a function of the type of gas exchange device used. Perfusion (2007) 22, 15-21.
Modification of an extracorporeal life support circuit for intraoperative correction of complex congenital heart disease
Authors: Toomasian John M , Vricella Luca A , Black Michael D
Published: July 2007

Extracorporeal life support (ECLS) was established in a newborn infant diagnosed with severe respiratory failure secondary to complex congenital heart disease. After 4 days of ECLS support in the intensive care unit, the infant was brought to the operating room for repair of the primary lesion. Due to concerns related to recurrent respiratory failure associated with blood contact to a new extracorporeal circuit, the existing ECLS circuit was modified for use in the operating room. This report describes the circuit modification steps and challenges related to running a modified ECLS circuit for cardiopulmonary support during cardiac surgery. Perfusion (2007) 22, 35—40.
Effects of gelatine and medium molecular weight starch as priming fluid in cardiopulmonary bypass - a randomised controlled trial
Authors: Yap WW , Young D. , Pathi V.
Published: July 2007

Perioperative volume replacement after cardiopulmonary bypass is complicated by post-bypass systemic inflammatory process. The aim of this study was to assess the effects of using two different colloid solutions as priming fluids in cardiopulmonary bypass. The study's primary end point was to measure the amount of fluid replacement needed during and post-cardiopulmonary bypass; blood loss, change in blood profile and intraocular pressure were secondary end points, used as measures of plasma oncotic pressures. Patients undergoing coronary artery bypass grafting were recruited. Both patients and surgeons were blinded to receive either Gelofusine® or Voluven® as priming fluids. At fixed intervals during cardiopulmonary bypass, the patients had their intraocular pressures measured. Intra and postoperative fluid replacement was in the form of 4.5% human albumin and the amount was recorded for each subject. The result did not show any significant differences in the amount of fluid needed to be replaced, in blood loss or in blood profile between the two groups. However, it showed an increase in intraocular pressure in both groups once cardiopulmonary bypass commenced. The average intraocular pressure was higher in the Gelofusine ® group compared to the Voluven® group. The significant increase in intraocular pressure measurements in the Gelofusine® group compared to the Voluven® group support the hypothesis that Voluven maintains the plasma oncotic pressure better and reduces fluid shift. Perfusion (2007) 22, 57—62.
Effect of acetaminophen, a cyclooxygenase inhibitor, on Morris water maze task performance in mice
Authors: Ishida Takayuki , Sato Tomoaki , Irifune Masahiro , Tanaka Koh-ichi , Nakamura Norifumi , Nishikawa Takashige
Published: July 2007

Although the mechanism of action of acetaminophen (AAP) is not fully understood, some studies suggest that AAP and phenacetin (PHE) are selective cyclooxygenase (COX)-3 inhibitors. To examine the participation of COX-3 in memory formation, water maze performance was studied in mice treated with AAP, PHE or other COX inhibitors. Mice received intraperitoneal injections of drugs immediately after each training session. Administration of high-dose AAP [302.3 mg/kg (IC50 for COX-2)] or PHE [179.2 mg/kg (IC50 for COX-2)] and of non-specific (indomethacin: 20 mg/kg) or specific COX-2 (NS-398: 10 mg/kg) inhibitor impaired the performance in hidden platform (HP) not visible platform (VP) tasks, whereas low-dose (15.1 mg/kg) AAP facilitated performance in HP and VP tasks. The facilitation of performance by low-dose AAP was reversed by co-administration with a 5-HT1/2 receptor antagonist (methysergide: 0.47 mg/kg). The middle-dose [69.5 mg/kg (IC50 for COX-3)] of AAP, the PHE [17.9 mg/kg (IC50 for COX-3)] and a specific COX-1 inhibitor (piroxicam: 10—20 mg/kg) did not influence performance in either task. These results suggest that the memory impairment by high-dose AAP and PHE and facilitation of performance by low-dose AAP could involve endogenous COX-2 and serotonergic neuronal activity, but not COX-3, respectively.
Attention switching after dietary brain 5-HT challenge in high impulsive subjects
Authors: Markus C. Rob , Jonkman Lisa M.
Published: July 2007

High levels of impulsivity have adverse effects on performance in cognitive tasks, particularLy in those tasks that require high attention investment. Furthermore, both animal and human research has indicated that reduced brain serotonin (5-HT) function is associated with increases in impulsive behaviour or decreased inhibition ability, but the effects of 5-HT challenge have not yet been investigated in subjects vulnerable to impulsivity.

The present study aimed to investigate whether subjects with high trait impulsivity perform worse than low impulsive subjects in a task switching paradigm in which they have to rapidly shift their attention between two response rules, and to investigate the influence of a 5-HT enhancing diet. Healthy subjects with high ( n = 19) and low ( n = 18) trait impulsivity scores participated in a double-blind placebo-controlled study. All subjects performed the attention switch task in the morning following breakfast containing either tryptophan-rich alpha-lactalbumin (4.8 g/100 g TRP) or placebo protein (1.4 g/100 g TRP).

Whereas there were no baseline differences between high and low impulsive subjects in task switching abilities, high impulsive subjects made significantly more switch errors and responded slower after dietary 5-HT stimulation, whereas no dietary effects were found on task switching performance in low-impulsive subjects. The deterioration in task switching performance induced by the 5-HT enhancing diet in high impulsive subjects was suggested to be established by general arousal/attention-reducing effects of 5-HT, which might have a larger impact in high impulsive subjects due to either different brain circuitry involved in task switching in this group or lower baseline arousal levels.
Postarthroscopic Glenohumeral Chondrolysis
Authors: Hansen Brent P. , Beck Charles L. , Beck Elizabeth P. , Townsley Robert W.
Published: July 2007

Background

Recent reports have noted the appearance of postarthroscopic glenohumeral chondrolysis. Although this devastating process has been identified, no cause has been directly identified.

Hypothesis

A cause of postarthroscopic glenohumeral chondrolysis will be associated with a specific factor (ie, implanted device, surgical technique, etc), and this factor can be identified by a review and comparison of cases seen in the senior author's office.

Study Design

Case series; Level of evidence, 4.

Methods

Analyze possible etiologic factors with imaging studies, demographics, history, and physical examinations of 10 patients (12 shoulders) with postarthroscopic glenohumeral chondrolysis, and then compare perisurgical information with a focused chart review and comparison with the rest of the 177 arthroscopic shoulder surgeries in the same period of time.

Results

There were 12 cases of postarthroscopic glenohumeral chondrolysis (all were the senior author's patients). Four common factors were identified, and only high-flow intra-articular pain pump catheters filled with bupivacaine and epinephrine were a new addition to years of shoulder surgery by the senior author; 177 shoulders underwent arthroscopy in the identified time frame, and only 19 shoulders, of 30 with capsular procedures, had intra-articular pain pump catheters filled with bupivacaine and epinephrine. Of these, 12 have been identified with chondrolysis.

Conclusion

Use of intra-articular pain pump catheters eluting bupivacaine with epinephrine appear highly associated with postarthroscopic glenohumeral chondrolysis.

Clinical Relevance

Intra-articular pain pump catheters, especially those eluting bupivacaine with epinephrine, should be avoided until further investigation.
Heat-Related Illness in Athletes
Authors: Howe Allyson S. , Boden Barry P.
Published: July 2007

Heat stroke in athletes is entirely preventable. Exertional heat illness is generally the result of increased heat production and impaired dissipation of heat. It should be treated aggressively to avoid life-threatening complications. The continuum of heat illness includes mild disease (heat edema, heat rash, heat cramps, heat syncope), heat exhaustion, and the most severe form, potentially life-threatening heat stroke. Heat exhaustion typically presents with dizziness, malaise, nausea, and vomiting, or excessive fatigue with accompanying mild temperature elevations. The condition can progress to heat stroke without treatment. Heat stroke is the most severe form of heat illness and is characterized by core temperature >104°F with mental status changes. Recognition of an athlete with heat illness in its early stages and initiation of treatment will prevent morbidity and mortality from heat stroke. Risk factors for heat illness include dehydration, obesity, concurrent febrile illness, alcohol consumption, extremes of age, sickle cell trait, and supplement use. Proper education of coaches and athletes, identification of high-risk athletes, concentration on preventative hydration, acclimatization techniques, and appropriate monitoring of athletes for heat-related events are important ways to prevent heat stroke. Treatment of heat illness focuses on rapid cooling. Heat illness is commonly seen by sideline medical staff, especially during the late spring and summer months when temperature and humidity are high. This review presents a comprehensive list of heat illnesses with a focus on sideline treatments and prevention of heat illness for the team medical staff.
Satisfaction With Dental Appearance Among Diverse Groups of Dentate Adults
Authors: Xiaoxian Meng  , Gilbert Gregg H. , Duncan R. Paul , Heft Marc W.
Published: July 2007

Objectives: To quantify (a) the prevalence of dissatisfaction with dental appearance in a diverse sample of dentate adults and (b) the associations between dissatisfaction with dental appearance, sociodemographic factors, and other measures of oral health. Methods: Data were taken from the Florida Dental Care Study , a population-based longitudinal cohort study of oral health and related behaviors. The sample included 873 participants at baseline. Descriptive analysis and logistic regression were conducted to analyze the baseline data in the current report. Results: Females, problem-oriented dental attenders, and participants who had not completed high school were significantly more dissatisfied with their dental appearance than their respective counterparts. Dissatisfaction with dental appearance was also independently associated with six specific clinical and self-reported measures of oral health. Discussion: Dissatisfaction with dental appearance was common in this population-based sample of middle-aged and older adults, and was significantly associated with key sociodemographic and oral health factors.
Synthesis and Characterization of Organosoluble Optically Active Poly(ester-imide)s Derived from Trimellitic Anhydride, L-Methionine and Bisphenols
Authors: Mallakpour Shadpour , Meratian Shahrzad
Published: July 2007

The reaction of thionyl chloride in pyridine as a condensing agent was used for the direct polycondensation of N-trimellitylimido-L-methionine (4) with various aromatic diols such as bisphenol A (5a), phenolphthalein (5b), 1,5-naphthalendiol (5c), 2,6-dihydroxytoluene (5d), hydroquinone (5e), biphenyl-2,2'-diol (5f), 1,4-dihydroxyanthraquinone (5g). This reaction leads to the formation of novel optically active poly(ester-imide)s (PEI)s. The resulting PEIs were obtained in good yields and exhibited low to moderate inherent viscosities ranging from 0.15 to 0.40 dL g-1. All of the PEIs showed good solubility and readily dissolved in solvents such as N-methyl-2-pyrrolidinone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), pyridine and tetrahydrofuran. Thermogravimetric analysis showed that PEI 6b was stable, with 10% weight loss recorded above 370 oC in nitrogen. All of the above polymers were characterized by FTIR, specific rotation, and representative PEIs were also characterized by 1 H NMR, elemental analysis, and thermogravimetric analysis. The structural characterization and physical properties of these new optically active PEIs are reported.
The Non-isothermal Degradation Process of some Polyethers and Azo-polyethers
Authors: Hurduc Nicolae , Lisa Gabriela , Damian Cristina , Toader Violeta , Hurduc Natalia
Published: July 2007

The paper presents a non-isothermal kinetic study of the degradation process of some aromatic copolyethers containing a tetra-methylenic spacer. The polymers were synthesized using the phase transfer catalysis technique, starting from 1,4-dichlorobutane and various bisphenols (4,4'-dihidroxyazobenzene, 4,4'-dihydroxydiphenyl, bisphenol A and 2,7-dihydroxynaphthlene). Dynamic thermal analysis methods such as ATG, DTG and ATD were used. In order to work out the basic kinetic parameters and the reliance between activation energy and conversion degree, differential methods based on the `order reaction model' were applied and standard kinetic models were also used. The thermostability of the good samples up to 320°C was demonstrated. The degradation mechanism took place by successive reactions, controlled by a nucleation process influenced by the polymer molecular structure.
Radiation Effects on Thermal Properties of Polymers. II. Polytetrafluoroethylene
Authors: Briskman B.A. , Tlebaev K.B.
Published: July 2007

The second paper in a set of reviews of radiation effects on thermal properties of polymers is devoted to polytetrafluoroethylene (PTFE). The specificity of the radiation physics and chemistry of this material is relatively well investigated and it is widely used in different applications under radiation impact. Degradation of thermal and structure properties is discussed, and models for the description of these effects are presented. Specific problems such as the action of different kinds of radiation, dose rate effects, especially under vacuum, and deviation of PTFE structure from the two-phase model are also examined.
Lateglacial and Holocene wet—dry cycles in southern Patagonia: chronology, sedimentology and geochemistry of a lacustrine record from Laguna Potrok Aike, Argentina
Authors: Haberzettl Torsten , Corbella Hugo , Fey Michael , Janssen Stephanie , Lücke Andreas , Mayr Christoph , Ohlendorf Christian , Schäbitz Frank , Schleser Gerhard H. , Wille Michael , Wulf Sabine , Zolitschka Bernd
Published: July 2007

A high-resolution multiproxy geochemical approach was applied to the sediments of Laguna Potrok Aike in an attempt to reconstruct moist and dry periods during the past 16 000 years in southeastern Patagonia. The age—depth model is inferred from AMS 14C dates and tephrochronology, and suggests moist conditions during the Lateglacial and early Holocene (16 000—8700 cal. BP) interrupted by drier conditions before the beginning of the Holocene (13 200—11 400 cal. BP). Data also imply that this period was a major warm phase in southeastern Patagonia and was approximately contemporaneous with the Younger Dryas chronozone in the Northern Hemisphere (12 700—11 500 cal. BP). After 8650 cal. BP a major drought may have caused the lowest lake level of the record. Since 7300 cal. BP, the lake level rose and was variable until the `Little Ice Age', which was the dominant humid period after 8650 cal. BP.
Age and significance of aeolian sediment reworking on high plateaux in the Scottish Highlands
Authors: Morrocco Stefan M. , Ballantyne Colin K. , Spencer Joel Q.G. , Robinson Ruth A.J.
Published: July 2007

Holocene aeolian sand sheets at the margins of high-level deflation surfaces in the Scottish Highlands commonly comprise two units: a lower weathered unit representing slow accumulation throughout much or all of the Holocene, and an upper unit of structureless sand that is inferred to represent recent erosion of aeolian deposits and aeolisols from adjacent plateaux. OSL dating of samples from above and below the upper—lower unit contact at three sites in NW Scotland places the onset of upper unit sediment accumulation within the interval AD 1550—1700. Accumulation rates calculated from OSL ages confirm rapid accumulation of upper-unit deposits. The timing of the onset of upper-unit sand accumulation excludes expansion of sheep grazing, intrinsic instability and atmospheric pollution as triggers of plateau-surface vegetation degradation and consequent erosion, but favours climatic deterioration (increased wind stress and possibly prolonged snow-lie) during the `Little Ice Age' as the likely cause. This explanation does not, however, apply in all cases; at an OSL-dated site in the Grampian Highlands upper-unit aeolian sand accumulation commenced around AD 1900.
The Culture of Pregnancy and Infant Care in African American Women: An Ethnographic Study
Authors: Savage Christine L. , Anthony Jean , Lee Rebecca , Kappesser Mary L. , Rose Barbara
Published: July 2007

In Hamilton County, Ohio, the infant mortality rate for African American infants in 2002 was 18.1 per 1,000 live births compared with 14.4 for the United States. It is essential to engage community residents and leaders in identifying the underlying cultural factors contributing to this disparity. The purpose of the study was to explore the cultural contexts of prenatal and infant care practices among African American women of childbearing age living in an urban community located in Hamilton County, Ohio. This was an ethnographic community-based participatory research study. Seven participants were recruited for the study. Family support from mothers and sisters in obtaining needed resources related to pregnancy and child care emerged as the central theme. A strong family-based social network was core to the culture of pregnancy and infant care for these women. Nurses should consider developing family-centered interventions to reduce disparity in infant health.
An Investigation of Habitual and Incidental Physical Activity Among Costa Rican and Costa Rican American Teenage Girls
Authors: D'Alonzo Karen T. , Cortese Lauren B.
Published: July 2007

A comparative survey design was used to examine habitual and incidental physical activity among native Costa Rican (CR) and Costa Rican American (CRA) adolescent girls. The purposive sample included 17 girls (ages 12-19 years) living in Limon, Costa Rica (n = 11), and the metropolitan New York/New Jersey area (n = 6). Participants in the CR group had significantly higher levels of habitual (p = .04), incidental (p = .02), and combined (p = .03) physical activity as compared with those on the CRA group. Dance was a preferred form of activity for both groups. The relationship between habitual and incidental physical activity was not significant, underscoring the need to address both variables in assessment of total physical activity. The findings suggest a need to prioritize the promotion of physical activity among immigrant teenage girls using culturally valued methods.
Inequities in Screening for Sexually Transmitted Infections in African American Adolescents: Can Health Policy Help?
Authors: Roberson Donna W.
Published: July 2007

Although rates of sexually transmitted infections (STIs) in African Americans are higher than other populations, there are disparities in the screening and treatment of STIs for African American adolescents. Many African Americans distrust the health care system, resulting in a reluctance to seek health care. Adolescents may lack access to and the resources to pay for health care. This article reviews historical events believed to influence African American distrust of the health care system, discusses socioeconomic factors influencing adolescent access to services, and offers descriptions of services available to assist adolescents in receiving preventative services. Last, potential health policy solutions for nurses are noted.
Intersubjective Implosions
Authors: Borchard Kurt
Published: July 2007

In the past 8 years, five major structures on the Las Vegas Strip (The Dunes, Landmark, Hacienda, Sands, and Aladdin hotels) have been imploded. In this intersubjective ethnography, the author utilizes personal reflection to discuss the problematic intersection of biography, changes in the Las Vegas skyline, economic trends, and their connection to history. This intersubjective ethnography captures contradictions and paradoxes through interpretive accounts of the author's dynamic relationship to others and his environment.
Contradictory Subjectivity: Movies, Apartheid, and Postmodernism
Authors: Tomaselli Keyan G.
Published: July 2007

Most of the author's writing and film/video making until the mid-1990s was couched within an antiapartheid, explicitly Marxist framework. But, like all individuals, he has his contradictions. These are derived from his class, eth nic, and racial determinations. This reflexive article negotiates the author's experiences during the apartheid and postapartheid eras, from modernism to postmodernism. This chapter examines some of these influences on his professional experience, teaching, and research.
Problems of Cultural Analysis and Policy in the Information Age
Authors: McGuigan Jim
Published: July 2007

The term culture is now used in so many different ways that its analytical util ity is in doubt. For policy-oriented cultural studies, it is wisest to concentrate on practices that are first and foremost about signification, identity, and pleasure. Also, policy-oriented research should not be reduced to adminis trative usefulness. From a critical perspective, technological determinism in communications and culture must be treated with skepticism. In this connec tion, Manuel Castells's information age thesis is examined. The adequacy of his model of inclusion and exclusion is additionally called into question. Despite its many strengths, Castells's thesis distracts attention from pro cesses that are anterior to—albeit mediated by—the development of infor mation and communication technologies (ICTs), most notably exploitation on a global scale. In contrast, Naomi Klein's research focuses on the mate rial and ideological connections of branding culture—which is indeed "cul ture" because it foregrounds signification, identity, and pleasure—to the extreme exploitation of sweatshop labor.
In Pursuit of the Good Life: High School Students’ Constructions of Morality and the Implications for Educational Leadership
Authors: Mirón Louis F. , Bogotch Ira E. , Biesta Gert J. J.
Published: July 2007

In this interpretative study, the authors analyze the construction of three moral values in the context of inner-city high schools experiencing widespread poverty and racism. These values are trust, respect, and care. The authors demonstrate how the processes of social and discursive construction of morality differentially influence lived moral experiences for African American high school students from similar socioeconomic backgrounds. Differences are largely explained by the articulation of a strong African American tradition (racial-ethnic pride) in the magnet school, “City High.” By contrast, a profound lack of trust and respect for this tradition seems to hinder student voice and the pursuit of “moral equality” and access to quality public schooling in the comparative school, “Neighborhood High.”