bluuebunny/crossref_metadata_2025 huggingface dataset:
Sca-1
+
Progenitors Derived From Embryonic Stem Cells Differentiate Into Endothelial Cells Capable of Vascular Repair After Arterial Injury
Authors: Xiao Qingzhong , Zeng Lingfang , Zhang Zhongyi , Margariti Andriana , Ali Ziad A , Channon Keith M. , Xu Qingbo , Hu Yanhua
Published: August 2006

Background—

Embryonic stem cells possess the ability to differentiate into endothelium. The ability to produce large volumes of endothelium from embryonic stem cells could provide a potential therapeutic modality for vascular injury. We describe an approach that selects endothelial cells using magnetic beads that may be used therapeutically to treat arterial injury.

Methods and Results—

Large numbers of endothelial cells (ECs) with high purity were produced using Sca-1
+
cells isolated with magnetic beads from predifferentiated embryonic stem cells (ESCs) cultured in α-MEM containing 10 ng/mL VEGF
165
for a minimum of 21 days (esEC). The transcription regulator histone deacetylase (HDAC3) was essential for VEGF-induced EC differentiation. Immunofluorescence or fluorescence-activated cell sorter (FACS) analysis revealed that esECs expressed a full range of EC lineage-specific markers including CD31, CD106, CD144, Flk-1, Flt-1, and von Willebrand factor (vWF). FACS analysis confirmed that 99% of esECs were CD31-positive and 75% vWF-positive. Furthermore, almost all cells were positive for DiI-acLDL uptake. When matrigel containing esECs was subcutaneously implanted into mice, various vessel-like structures were observed indicating their endothelial cell like phenotype. In keeping with this, when esECs infected with adenovirus-LacZ were injected into denuded femoral arteries of mice, they were found to form a neo-endothelium that covered the injured areas (86%±13.6%), which resulted in a 73% decrease in neointimal area 2 weeks after injury.

Conclusions—

We conclude that Sca-1
+
cells can differentiate into functional ECs via activation of HDAC3, accelerating re-endothelialization of injured arteries and reducing neointima formation.
High-Molecular-Weight Kininogen Fragments Stimulate the Secretion of Cytokines and Chemokines Through uPAR, Mac-1, and gC1qR in Monocytes
Authors: Khan Mohammad M. , Bradford Harlan N. , Isordia-Salas Irma , Liu Yuchuan , Wu Yi , Espinola Ricardo G. , Ghebrehiwet Berhane , Colman Robert W.
Published: August 2006

Objective—

Plasma high-molecular-weight kininogen (HK) is cleaved in inflammatory diseases by kallikrein to HKa with release of bradykinin (BK). We postulated a direct link between HKa and cytokine/chemokine release.

Methods and Results—

HKa, but not BK, releases cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and chemokines IL-8 and MCP-1 from isolated human mononuclear cells. At a concentration of 600 nM, glutathione-S-transferase (GST) fusion proteins of kininogen domain 3 (D3), a fragment of domain 3, E7P (
aa
G255-Q292), HK domain 5 (D5), the D5 recombinant peptides HG (aa K420-D474) and HGK (aa H475-S626) stimulated secretion of IL-1β from mononuclear cells. Monoclonal antibodies (MAbs) specific for D5 or specific for D3 blocked release of IL-1β by HKa, supporting the importance of both domains. Antibodies to HK receptors on leukocytes including Mac-1, LFA-1, uPAR, and C1qR inhibited IL-1β secretion induced by tKa 98%, 89%, 85%, and 62%, respectively. Fractionation of mononuclear cells identified the responsible cell, a blood monocyte. Inhibitors of signaling pathways NFkB, JNK, and p38 but not extracellular signal-regulated kinase (ERK) decreased cytokine release from mononuclear cells. HKa increased the synthesis of IL-1β as deduced by an increase of IL-1β mRNA at 1 to 2 hours.

Conclusions—

HKa domains 3 and 5 may contribute to the pathogenesis of inflammatory diseases by releasing IL-1β from human monocytes using intracellular signaling pathways initiated by uPAR, β2 integrins and gC1qR.
Lipoprotein-Associated Phospholipase A
2
and Prognosis After Myocardial Infarction in the Community
Authors: Gerber Yariv , McConnell Joseph P. , Jaffe Allan S. , Weston Susan A. , Killian Jill M. , Roger Véronique L.
Published: August 2006

Objective—

We evaluated the role of lipoprotein-associated phospholipase A
2
(Lp-PLA
2
), an inflammatory biomarker, in defining risk after myocardial infarction (MI).

Methods and Results—

Olmsted County, Minn, residents who experienced an MI meeting standardized criteria between 2003 and 2005 (n=271) were prospectively identified and followed. Lp-PLA
2
levels were measured at baseline and evaluated along with traditional risk indicators. Lp-PLA
2
was modestly associated with total and low-density lipoprotein cholesterol, smoking, and age (inversely) but not with MI characteristics or severity, comorbidities, C-reactive protein, or the time from symptom onset to blood sampling. During the first year of follow-up, 42 deaths occurred. The survival estimates (95% confidence intervals [CI]) at 1 year were 92% (86% to 98%), 85% (78% to 93%), and 74% (65% to 84%) in the lowest, middle, and upper Lp-PLA
2
tertiles, respectively (
P
=0.007). After adjustment for age and sex, the hazard ratios for death in the middle and upper Lp-PLA
2
tertiles were 2.20 (95% CI: 0.88 to 5.54) and 4.93 (95% CI: 2.10 to 11.60), compared with the lowest tertile, respectively (
P
trend
<0.001). Further adjustment for other risk indicators resulted in even stronger associations. Lp-PLA
2
also contributed to risk discrimination as indicated by the increases in the area under the receiver operating characteristic curves obtained in each of the models examined (all
P
≤0.05).

Conclusions—

Among community subjects presenting with MI, increased Lp-PLA
2
levels measured early after MI are strongly and independently associated with mortality and provide incremental value in risk discrimination over traditional predictors.
Serum Levels of Mannose-Binding Lectin and the Risk of Future Coronary Artery Disease in Apparently Healthy Men and Women
Authors: Keller Tymen T. , van Leuven Sander I. , Meuwese Marijn C. , Wareham Nicholas J. , Luben Robert , Stroes Erik S. , Hack C. Erik , Levi Marcel , Khaw Kay-Tee , Boekholdt S. Matthijs
Published: August 2006

Objective—

To determine the association between serum levels of mannose-binding lectin (MBL) and the risk of future coronary artery disease (CAD) in apparently healthy men and women.

Methods and Results—

We performed a prospective case-control study among apparently healthy men and women nested in the EPIC-Norfolk cohort. Baseline concentrations of MBL were measured in serum samples of 946 patients who experienced a myocardial infarction or died of CAD during follow-up, and 1799 matched controls who remained free of CAD. Among men, median MBL levels were 1.63 ng/mL (interquartile range [IQR]: 0.59 to 3.80) in cases and 1.20 ng/mL (IQR: 0.48 to 3.37) in controls. Among women, median MBL levels were 1.02 ng/mL (IQR: 0.43 to 2.95) in cases and 1.01 ng/mL (IQR: 0.43 to 2.94) in controls. After adjustment, the odds ratio in men for future CAD was 1.59 (95% confidence interval [CI]: 1.09 to 2.32;
P
for linearity=0.01) for those in the highest quartile compared with those in the lowest quartile. In women no such relation was observed.

Conclusions—

Elevated levels of MBL are associated with an increased risk of future CAD in apparently healthy men but not in women. The sex difference merits further exploration.
In Vivo Characterization and Quantification of Atherosclerotic Carotid Plaque Components With Multidetector Computed Tomography and Histopathological Correlation
Authors: de Weert Thomas T. , Ouhlous Mohamed , Meijering Erik , Zondervan Pieter E. , Hendriks Johanna M. , van Sambeek Marc R.H.M. , Dippel Diederik W.J. , van der Lugt Aad
Published: August 2006

Objective—

In a previous in vitro study we have demonstrated that atherosclerotic plaque components can be characterized with multidetector computed tomography (MDCT) based on differences in Hounsfield values (HV). Now we evaluated the use of MDCT in vivo to characterize and quantify atherosclerotic carotid plaque components compared with histology as reference standard.

Methods and Results—

Fifteen symptomatic patients with carotid stenosis (>70%) underwent MDCT angiography before carotid endarterectomy (CEA). From each CEA specimen 3 histological sections and corresponding MDCT images were selected. The HV of the major plaque components were assessed. The measured HV were: 657±416HU, 88±18HU, and 25±19HU for calcifications, fibrous tissue, and lipid core, respectively. The cut-off value to differentiate lipid core from fibrous tissue and fibrous tissue from calcifications was based on these measurements and set at 60 HU and 130 HU, respectively. Regression plots showed good correlations (
R
2
>0.73) between MDCT and histology except for lipid core areas, which had a good correlation (
R
2
=0.77) only in mildly calcified (0% to 10%) plaques.

Conclusions—

MDCT is able to quantify total plaque area, calcifications, and fibrous tissue in atherosclerotic carotid plaques in good correlation with histology. Lipid core can only be adequately quantified in mildly calcified plaques.
Induction of Monocytic Tissue Factor Expression After Rewarming From Hypothermia In Vivo Is Counteracted by Heat Shock in c-Jun–Dependent Manner
Authors: Egorina Elena M. , Sovershaev Mikhail A. , Kondratiev Timofei V. , Olsen Jan O. , Tveita Torkjel , Østerud Bjarne
Published: August 2006

Objective—Triggering of tissue factor (TF)-mediated blood coagulation leads to the development of disseminated intravascular coagulation during rewarming from hypothermia. We studied post-rewarming TF levels, activity, and surface redistribution, along with the regulation of TF gene transcription in mononuclear cells (MNCs) obtained from an in vivo rat model.

Methods and Results—Rewarming after a 5-hour episode of 15°C hypothermia caused an increase in TF activity, protein levels, and externalization of TF antigen in rat MNCs. This was accompanied by a dramatic elevation of c-Jun and JNK phosphorylation, and the absence of EGR-1 and NF-κB activation. To search for a stimulus to counteract c-Jun–mediated induction of TF activity in MNCs from rewarmed rats, we applied heat shock pretreatment one day before the hypothermia/rewarming experiment. This restored post-rewarming TF activity, protein levels, and surface-to-total TF ratio in rat MNCs to normothermic levels. Furthermore, in heat shock-pretreated animals, rewarming failed to increase phosphorylated c-Jun and JNK levels. We attribute this to the profound overexpression of heat shock protein 70 and inhibition of JNK.

Conclusions—MNCs respond to rewarming from hypothermia by an induction of active TF antigen. This effect is dependent on c-Jun activation and is abolished by heat shock pretreatment.
Activation of D3Dopamine Receptor Decreases Angiotensin II Type 1 Receptor Expression in Rat Renal Proximal Tubule Cells
Authors: Zeng Chunyu , Liu Yan , Wang Zheng , He Duofen , Huang Lan , Yu Peiying , Zheng Shaopeng , Jones John E. , Asico Laureano D. , Hopfer Ulrich , Eisner Gilbert M. , Felder Robin A. , Jose Pedro A.
Published: August 2006

The dopaminergic and renin angiotensin systems interact to regulate blood pressure. Disruption of the D3dopamine receptor gene in mice produces renin-dependent hypertension. In rats, D2-like receptors reduce angiotensin II binding sites in renal proximal tubules (RPTs). Because the major D2-like receptor in RPTs is the D3receptor, we examined whether D3receptors regulate angiotensin II type 1 (AT1) receptors in rat RPT cells. The effect of D3receptors on AT1receptors was studied in vitro and in vivo. The D3receptor agonist PD128907 decreased AT1receptor protein and mRNA in WKY RPT cells and increased it in SHR cells. PD128907 increased D3receptors in WKY cells but had no effect in SHR cells. D3/AT1receptors colocalized in RPT cells; D3receptor stimulation decreased the percent amount of D3receptors that coimmunoprecipitated with AT1receptors to a greater extent in WKY than in SHR cells. However, D3receptor stimulation did not change the percent amount of AT1receptors that coimmunoprecipitated with D3receptors in WKY cells and markedly decreased the coimmunoprecipitation in SHR cells. The D3receptor also regulated the AT1receptor in vivo because AT1receptor expression was increased in kidneys of D3receptor–null mice compared with wild type littermates. D3receptors may regulate AT1receptor function by direct interaction with and regulation of AT1receptor expression. One mechanism of hypertension may be related to increased renal expression of AT1receptors due decreased D3receptor regulation.
Spatially Discordant Alternans in Cardiac Tissue
Authors: Sato Daisuke , Shiferaw Yohannes , Garfinkel Alan , Weiss James N. , Qu Zhilin , Karma Alain
Published: August 2006

Spatially discordant alternans, where the action potential duration (APD) and intracellular calcium transient (Ca
i
) alternate with opposite phase in different regions of tissue, is known to promote wave break and reentry. However, this phenomenon is not completely understood. It is known that alternans at the cellular level can be caused by dynamical instabilities arising from either membrane voltage (
V
m
) attributable to steep APD restitution or to calcium (Ca) cycling. Here, we used a mathematical model of intracellular Ca cycling, coupled with membrane ion currents, to investigate the dynamics of
V
m
and Ca
i
transient alternans in an isolated cell, in two electrotonically coupled cells, and in 1D spatially homogeneous tissue. Our main finding is a novel instability mechanism in which the bidirectional coupling of
V
m
and Ca
i
can drive the Ca
i
transient of two neighboring cells to be out of phase. This instability is manifested in cardiac tissue by the dynamical formation of spatially discordant alternans. In this case, Ca
i
transient alternans can reverse phase over a length scale of one cell, whereas APD alternans reverses phase over a much longer length scale set by the electrotonic coupling. We analyze this mechanism in detail and show that it is a robust consequence of experimentally established properties of the bidirectional coupling between Ca cycling and
V
m
dynamics. Finally, we address the experimental relevance of these findings and suggest physiological conditions under which these patterns can be observed.
Carotid Artery Stenting
Authors: Cremonesi Alberto , Setacci Carlo , Bignamini Angelo , Bolognese Leonardo , Briganti Francesco , Di Sciascio Germano , Inzitari Domenico , Lanza Gaetano , Lupattelli Luciano , Mangiafico Salvatore , Pratesi Carlo , Reimers Bernard , Ricci Stefano , de Donato Gianmarco , Ugolotti Ugo , Zaninelli Augusto , Gensini Gian Franco
Published: August 2006

Background and Purpose—

The prevention of stroke and the correct treatment of carotid artery stenosis represent today a major debate in cardiovascular medicine. Beside carotid endarterectomy, carotid angioplasty and stenting is becoming more widely performed for the treatment of severe carotid obstructive disease, and is now accepted as a less invasive technique that may provide an alternative for selected patients, particularly those with significant comorbidities. An Italian multidisciplinary task force, in which converged the most representative scientific societies involved in carotid treatment, was created to provide neurologists, radiologist, cardiologists, vascular surgeons, and all those involved in prevention and treatment of carotid disease with a simple, clear and updated evidence-based consensus document.

Summary of Review—

This First Consensus Document of the ICCS (Italian Consensus Carotid Stenting)/SPREAD group addressed the main issues related to methodology, definition of symptomatic and asymptomatic carotid stenosis, indication and procedures for carotid artery stenting, including the use of devices for preventing procedural embolic complications. Special attention was paid to credentials and competency for physicians qualifications to perform vascular angioplasty and stent placement, including training, acceptable complication rates and certification.

Conclusions—

As any guideline or consensus statement, also this document is valid as long as the evidence on which it is based remains up-to-date. In such a fast-evolving field of medicine as the management of carotid stenosis, it is mandatory to stimulate a continuous and fruitful discussion among all the professionals involved in this very evolutionary field.
Long-Term Effects of 6-Week Whole-Body Vibration on Balance Recovery and Activities of Daily Living in the Postacute Phase of Stroke
Authors: van Nes Ilse J.W. , Latour Hilde , Schils Fanny , Meijer Ronald , van Kuijk Annet , Geurts Alexander C.H.
Published: August 2006

Background and Purpose—

The long-term effects of 6-weeks whole-body vibration, as a novel method of somatosensory stimulation, on postural control and activities of daily living were compared with those of 6 weeks of exercise therapy on music of the same intensity in the postacute phase of stroke.

Methods—

Fifty-three patients with moderate to severe functional disabilities were randomized within 6 weeks poststroke and within 3 days after admission to a rehabilitation center to either whole-body vibration or exercise therapy on music in addition to a regular inpatient rehabilitation program. The whole-body vibration group received 4×45-second stimulation on the Galileo 900 (30-Hz frontal plane oscillations of 3-mm amplitude) for 5 days per week during 6 weeks. The exercise therapy on music group received the same amount of exercise therapy on music. Outcome variables included the Berg Balance Scale, Trunk Control Test, Rivermead Mobility Index, Barthel Index, Functional Ambulation Categories, Motricity Index, and somatosensory threshold at 0, 6, and 12 weeks follow up.

Results—

At baseline, both groups were comparable in terms of prognostic factors and outcome measures. Both at 6 and 12 weeks follow up, no clinically relevant or statistical differences in outcome were observed between the groups. No side effects were reported.

Conclusions—

Daily sessions of whole-body vibration during 6 weeks are not more effective in terms of recovery of balance and activities of daily living than the same amount of exercise therapy on music in the postacute phase of stroke.
Intravenous Tissue Plasminogen Activator in Patients With Stroke Increases the Bioavailability of Insulin-Like Growth Factor-1
Authors: Wilczak Nadine , Elting Jan Willem , Chesik Daniel , Kema Ido P. , De Keyser Jacques
Published: August 2006

Background and Purpose—

Insulin-like growth factor (IGF)-1 has potent neuroprotective properties. We investigated the effects of intravenous administration of tissue plasminogen activator (tPA) on serum levels of IGF-1 and IGF-binding protein (IGFBP)-3 in patients with acute ischemic stroke.

Methods—

Serum levels of total IGF-1, free IGF-1, and IGFBP-3 were measured by radioimmunoassay in 10 patients with ischemic stroke treated with intravenous tPA (0.9 mg/kg body weight) and 10 untreated controls.

Results—

During tPA treatment, total IGF-1 and IGFBP-3 serum levels did not change, but there was an &70% increase in free IGF-1 serum levels from 0.98±0.25 at baseline to 1.69±0.18 nmol/L at the end of the 1-hour infusion (
P
=0.01).

Conclusions—

Intravenous therapy with tPA enhances the bioavailability of IGF-1.
White Matter Lesions Are Associated With Progression of Medial Temporal Lobe Atrophy in Alzheimer Disease
Authors: de Leeuw Frank-Erik , Korf Esther , Barkhof Frederik , Scheltens Philip
Published: August 2006

Background and Purpose—

Medial temporal lobe atrophy (MTA) is a hallmark of Alzheimer disease (AD). Its progression is often seen during the course of AD, but its frequency and risk factors remain unclear.

Methods—

We investigated MTA in 35 patients with AD from whom sequential magnetic resonance imaging scans were available. White matter lesions (WML; for the periventricular [PV] and subcortical [SC] regions separately) and MTA were rated semiquantitatively.

Results—

In approximately two thirds of all patients, progression of MTA was found. The mean MTA progression was 0.8 (standard deviation: 0.5) and 0.3 (standard deviation: 0.4) for patients with or without PVWML at baseline (
P
=0.01). Patients who showed progression of PVWML over the course of their disease had a significantly higher mean progression of MTA than those without PVWML progression (0.9 [SD: 0.4]) and 0.4 [SD: 0.5];
P
=0.01). Patients with PVWML at baseline had a 40-fold increased risk for progression of MTA compared with those without baseline PVWML (odds ratio=40.0, 95% CI=1.3 to 1.2×10
3
,
P
=0.03). Patients with progression of PVWML during the course of the disease had an increased risk for MTA progression (odds ratio=3.7 per unit increase of progression of PVWML, 95% CI=1.1 to 12.9,
P
=0.04). There was higher risk for progression of MTA for those with progression of PVWML than those without (odds ratio=10.9, 95% CI=1.0 to 122.5,
P
=0.05). This was not found for SCWML.

Conclusions—

Our findings suggest that the presence and the progression of WML are associated with progression of MTA in AD. WML may be a predictor of the course of the disease and a potential treatment target in AD.
Sinus Venosus-Type Atrial Septal Defect
Authors: Cakmak Serkan , Goldman Christine , Bozio André , Nighoghossian Norbert , Derex Laurent , Trouillas Paul
Published: August 2006

Background and Purpose—

Sinus venosus defect is a rare cardiac abnormality, provoking an interatrial shunting outside the interatrial septum. Echographic diagnosis is difficult and may require examination by a specialized cardiologist.

Summary of Case—

We report the case of a young woman who presented with repeated episodes of hemiparesis.

Conclusions—

Surgical correction of sinus venosus defect led to disappearance of neurological symptoms.
Development of Complex Interventions in Stroke Care
Authors: Redfern Judith , McKevitt Christopher , Wolfe Charles D.A.
Published: August 2006

Background and Purpose—

Stroke care is complex, requiring input from professionals, patients and carers. Identifying and developing appropriate intervention components to meet these complex needs is difficult. The Medical Research Council (MRC) Framework for developing and evaluating ‘complex’ (nonpharmacological) interventions aims to improve intervention development. This study uses the Framework to review complex interventions in stroke care.

Methods—

Systematic review with multiple search strategies (electronic databases, recent journals, gray literature) was used. The MRC Framework was used to guide the search strategy and assess study quality. ‘Complex interventions’ were defined as educational/psychosocial interventions to change knowledge, beliefs or behaviors.

Results—

Sixty-seven studies were included: 39 randomized controlled trials (RCT) and 28 other designs. Complex interventions targeted healthcare professionals (17), and patients, carers and the general population (21 targeting primary or secondary prevention; 30 targeting adjustment and recovery after stroke). Compared with recovery studies, primary and secondary prevention studies were significantly less likely to have been evaluated in RCTs. Interventions evaluated in RCTs were significantly less likely to influence primary outcomes (26%) compared with other designs (44%). Theoretical grounding to support intervention choice was reported in 40 studies but only 14 were theoretically ‘well developed’; 21 RCTs listed multiple primary outcome measures, with 10 listing 5 or more. Of these only 3 reported considering statistical power before recruitment and none was sufficiently powered.

Conclusion—

Few complex interventions in stroke care have been adequately developed or evaluated. This may explain failures to demonstrate efficacy. In future, greater attention is needed to theoretical development and methodological quality.
Associations of
PPARGC1A
Haplotypes With Plaque Score but Not With Intima-Media Thickness of Carotid Arteries in Middle-Aged Subjects
Authors: Iglseder Bernhard , Oberkofler Hannes , Felder Thomas K. , Klein Kerstin , Paulweber Bernhard , Krempler Franz , Tregouet David A. , Patsch Wolfgang
Published: August 2006

Background and Purpose—

Peroxisome proliferator activated receptor γ coactivator 1α (PGC-1α,
PPARGC1A
) integrates the transcriptional program of mitochondrial biogenesis. Mitochondria are the main source of cellular reactive oxygen species implicated in atherogenesis. We therefore ascertained associations of
PPARGC1A
polymorphisms with asymptomatic carotid atherosclerosis.

Methods—

Eight single nucleotide polymorphisms tagging two haplotype blocks within
PPARGC1A
were studied in 1379 participants of the Salzburg Atherosclerosis Prevention Program in Subjects at High Individual Risk. Early atherosclerosis was assessed by intima-media thickness and extent of plaques (B-score) of the carotid arteries.

Results—

No associations of carotid artery intima-media thickness measurements with block 1 or 2 haplotype distributions or individual haplotypes were observed. However, the block 1 haplotype carrying the variant C nucleotide at −3974 relative to the transcription start site was associated with disease status defined by the presence of more than one minimal lesion and the −3974 C allele was associated with decreased risk (odds ratio=0.60,
P
=0.007) after adjustment for linkage disequilibrium between single nucleotide polymorphisms.

Conclusions—

These result are consistent with the concept that risk factors for distinct carotid phenotypes may vary and suggest, but do not prove, that PGC-1α may contribute to the regulation of atherogenic pathways.
A Step Forward in Studying the Compact Genetic Algorithm
Authors: Rastegar Reza , Hariri Arash
Published: August 2006

The compact Genetic Algorithm (cGA) is an Estimation of Distribution Algorithm that generates offspring population according to the estimated probabilistic model of the parent population instead of using traditional recombination and mutation operators. The cGA only needs a small amount of memory; therefore, it may be quite useful in memory-constrained applications. This paper introduces a theoretical framework for studying the cGA from the convergence point of view in which, we model the cGA by a Markov process and approximate its behavior using an Ordinary Differential Equation (ODE). Then, we prove that the corresponding ODE converges to local optima and stays there. Consequently, we conclude that the cGA will converge to the local optima of the function to be optimized.
Automated Global Structure Extraction for Effective Local Building Block Processing in XCS
Authors: Butz Martin V. , Pelikan Martin , Llorà Xavier , Goldberg David E.
Published: August 2006

Learning Classifier Systems (LCSs), such as the accuracy-based XCS, evolve distributed problem solutions represented by a population of rules. During evolution, features are specialized, propagated, and recombined to provide increasingly accurate subsolutions. Recently, it was shown that, as in conventional genetic algorithms (GAs), some problems require efficient processing of subsets of features to find problem solutions efficiently. In such problems, standard variation operators of genetic and evolutionary algorithms used in LCSs suffer from potential disruption of groups of interacting features, resulting in poor performance. This paper introduces efficient crossover operators to XCS by incorporating techniques derived from competent GAs: the extended compact GA (ECGA) and the Bayesian optimization algorithm (BOA). Instead of simple crossover operators such as uniform crossover or one-point crossover, ECGA or BOA-derived mechanisms are used to build a probabilistic model of the global population and to generate offspring classifiers locally using the model. Several offspring generation variations are introduced and evaluated. The results show that it is possible to achieve performance similar to runs with an informed crossover operator that is specifically designed to yield ideal problem-dependent exploration, exploiting provided problem structure information. Thus, we create the first competent LCSs, XCS/ECGA and XCS/BOA, that detect dependency structures online and propagate corresponding lower-level dependency structures effectively without any information about these structures given in advance.
A Business Ethics National Index (BENI)
Authors: Schwartz Mark S. , Weber James
Published: August 2006

A research instrument is developed and preliminarily validated to formally measure the level of national business ethics activity for any country in the world. The seven dimensions measured include (a) academia, (b) business, (c) social or ethical investment, (d) business ethics organizations, (e) government activity, (f) social activist groups, and (g) media coverage. Results from the validation survey and examples are provided for each of the dimensions. The article concludes with future research directions for the instrument.
The Effectiveness of Global Prohibition Regimes
Authors: Getz Kathleen A.
Published: August 2006

An increasing number of global policy regimes are intended to influence international business practices, but their effectiveness is uncertain. This article presents a conceptual framework for understanding the effectiveness of regimes, with seven propositions. The case of the evolving global anticorruption regime is described and used to test the propositions. Two key conclusions are (a) the difficulty of the problem being addressed is a key factor in limiting regime effectiveness and (b) this problem, as well as others, can be addressed in part by careful development of formal regime policies. Implications for scholarship and practice are presented.
Ethical Attitudes of Future Business Leaders
Authors: Albaum Gerald , Peterson Robert A.
Published: August 2006

Corporations have multiple stakeholder groups. One stakeholder group consists of undergraduate business students, who collectively constitute the future leadership of corporations. Given the so-called ethical and legal lapses that have occurred in the early 2000s in such companies as Enron, WorldCom, Arthur Andersen, and Tyco, it is increasingly important to know the ethical perspectives of future business leaders so that their future behavior can be anticipated. This article reports on a survey of nearly 3,000 undergraduate business students from 58 universities and colleges in 32 states regarding certain general ethics-related attitudes and the degree of ethicality these students possess. Survey findings are relatively consistent with those generally reported in the literature—female survey participants are slightly but significantly more ethically inclined than male survey participants, and survey participants who report being very religious are slightly but significantly more ethically inclined than survey participants who are less religious.
The Not So Clear-Cut Nature of Organizational Legitimating Mechanisms in the Canadian Forest Sector
Authors: Driscoll Cathy
Published: August 2006

The Canadian forest sector provides a rich contextual basis for examining organizational legitimacy and legitimating mechanisms. The author used qualitative methods and discourse analysis to explore how the Canadian forest sector exhibits a hybrid mix of substantive and symbolic management of legitimacy and of procedural and symbolic processes of legitimation. Findings support the mystifying nature of “green” legitimation and the superficial and mystifying nature of some of the discourse that is being used in this sector. In some cases, language is being used to attempt to change definitions of social legitimacy to enhance a record of sustainable forest management practice.
Universal Intracultural and Intercultural Dimensions of the Recalled Frequency of Emotional Experience
Authors: Kuppens Peter , Ceulemans Eva , Timmerman Marieke E. , Diener Ed , Kim-Prieto Chu
Published: August 2006

This study examined the relative contribution and the nature of dimensions underlying intracultural and intercultural differences in the recalled frequency of emotional experience. From 48 nations, 9,300 participants provided self-reports of the frequency of experienced emotions and several other variables relevant to emotional experience. The data were analyzed by means of multilevel component analysis, which decomposes the data into intracultural and intercultural components. The results showed that positive affect and negative affect emerged as universal dimensions underlying intracultural differences, accounting for the relatively largest part of variance in the data (40%). These dimensions were related to life satisfaction and other variables reflecting positive and negative affectivity. Two dimensions, reflecting positive emotions and inter-personal (negative) emotions, emerged as dimensions underlying nation-level differences, accounting for a smaller proportion of the variance (6%). Intercultural differences on these dimensions were related to nation-level life satisfaction, individualism, and the cultural appropriateness of experiencing corresponding emotions. Differences among individuals affect recalled emotional experience to a greater extent than differences among nations.
Convergent Evidence for the Multidimensionality of Self-Construal
Authors: Hardin Erin E.
Published: August 2006

Two studies test the multidimensional structure underlying the Self-Construal Scale. Study 1 cross-validated a multidimensional structure in new samples of Latino or Latina ( n= 350), African American ( n= 110), and European American ( n= 350) college students, supporting the generalizability of the multidimensional structure. Study 2 explored the utility of the six dimensions of self-construal in samples of Asian ( n= 59), Asian American ( n= 89), and European American ( n= 192) college students. Specific dimensions of self-construal accounted for more variance in social anxiety than the broader constructs of independence and interdependence did for the Asian Americans and European Americans, supporting the utility of measuring multidimensional self-construal in at least some groups. Implications for the measurement of multidimensional self-construal are discussed.
Evaluating Multilevel Models in Cross-Cultural Research
Authors: Cheung Mike W.-L. , Leung Kwok , Au Kevin
Published: August 2006

To assess how culture influences the behavior of people, multilevel models are an immediate choice for modeling the relationship at the levels of the individual and culture. The authors propose structural equation modeling (SEM) to test the universality of psychological processes at the individual and culture levels. Specifically, the structural equivalence of the measurement (where the instrument is measuring the same construct across countries) is first tested with meta-analytic SEM. If the measurement is structurally equivalent, cross-level equivalence (where the instrument is measuring similar constructs at different levels) will then be tested with multilevel SEM. A large data set on social axioms with 7,590 university students from 40 cultural groups was used to illustrate the procedures. The results showed that the structural equivalence of the social axioms was well supported at the individual level across 40 cultural groups, whereas the cross-level equivalence was partially supported. The superiority of the SEM approach and the theoretical meaning of its solution are discussed.
Acculturation Gap And Family Adjustment
Authors: Birman Dina
Published: August 2006

This study examined the impact of “acculturation gaps” on family adjustment of 115 adolescent refugees from the former Soviet Union and their parents. Acculturation and acculturation gaps were assessed with respect to the American and Russian culture and separately for identity, behavioral, and language competence dimensions of acculturation. Acculturation gaps were operationalized in two different ways in analyses: Difference scores were computed between parent and adolescent acculturation levels and used to predict family conflict and disagreement, and moderated regression analyses examined the main effects and interactions of parent and adolescent acculturation variables in predicting family conflict and disagreement. Results suggest the importance of some gaps for family discord, not others. In particular, gaps in American identity, American behavior, and Russian language were associated with greater family discord. Results also suggest the relative advantages of using the moderated regression approach to assess the impact of the acculturation gap and using bidirectional and multidimensional acculturation measures in acculturation gap research.
Neither Fight Nor Flight
Authors: Stanger-Ross Jordan
Published: August 2006

This article uses case studies of two Philadelphia synagogues to argue that postwar cities remained places of opportunity for creative local institutions and that the geographic flexibility of synagogues did not necessarily entail flight from declining urban areas. After their North Philadelphia Jewish residential enclave dissipated, Mikveh Israel and Rodeph Shalom recast the meaning of community and membership to accommodate their dispersed congregations. Rather than remaining neighborhood synagogues, Mikveh Israel and Rodeph Shalom connected members dispersed across the metropolitan area who were committed to preserving their religious institutions at the center of the city. Postwar Jewish community at these two synagogues developed metropolitan contours.
“From Protest to Politics”
Authors: Countryman Matthew J.
Published: August 2006

This article traces the origins of black independent electoral activism in Philadelphia during the 1970s to the Black Power movement of the 1960s. Specifically, it argues that Black Power activists in Philadelphia turned to electoral strategies to consolidate their efforts to achieve community control over public institutions in the city's black working-class neighborhoods. Finally, the article concludes with a brief evaluation of the careers of African American activist state legislators David Richardson and Roxanne Jones and W. Wilson Goode, Philadelphia's first African American mayor.
Strength in Numbers
Authors: Wood Andrew , Baer James A.
Published: August 2006

Tenant mobilization in cities across the Americas during the early twentieth century was rooted in local social networks articulated among women in tenement houses, neighborhood residents, ethnic groups, church members, and other forms of informal, nonworkplace association. What distinguishes tenant mobilization during the early twentieth century from earlier examples of urban popular protest is the changing nature of civil society and the state. A shift toward more broad-based democratic governance and a corresponding discourse of citizens’ rights provided renters a powerful new framework from which to articulate their grievances. Collective action on the part of tenants required not only ample resources “from below” but also an opening for such protest afforded “from above.” Critical support for popular mobilization can also be seen, as relatively new political elites broadened their popular base as they battled with more established powers
Interaction of Arch Type and Footwear on Running Mechanics
Authors: Butler Robert J. , Davis Irene S. , Hamill Joseph
Published: August 2006

Background

Running shoes are designed to accommodate various arch types to reduce the risk of lower extremity injuries sustained during running. Yet little is known about the biomechanical changes of running in the recommended footwear that may allow for a reduction in injuries.

Purpose

To evaluate the effects of motion control and cushion trainer shoes on running mechanics in low-and high-arched runners.

Study Design

Controlled laboratory study.

Methods

Twenty high-arched and 20 low-arched recreational runners (>10 miles per week) were recruited for the study. Three-dimensional kinematic and kinetics were collected as subjects ran at 3.5 ms-1 ± 5% along a 25-m runway. The motion control shoe evaluated was the New Balance 1122, and the cushioning shoe evaluated was the New Balance 1022. Repeated-measures analyses of variance were used to determine if low- and high-arched runners responded differently to motion control and cushion trainer shoes.

Results

A significant interaction was observed in the instantaneous loading rate such that the low-arched runners had a lower instantaneous loading rate in the motion control condition, and the high-arched runners had a lower instantaneous loading rate in the cushion trainer condition. Significant main effects for shoe were observed for peak positive tibial acceleration, peak-to-peak tibial acceleration, mean loading rate, peak eversion, and eversion excursion.

Conclusion

These results suggest that motion control shoes control rearfoot motion better than do cushion trainer shoes. In addition, cushion trainer shoes attenuate shock better than motion control shoes do. However, with the exception of instantaneous loading rate, these benefits do not differ between arch type.

Clinical Relevance

Running footwear recommendations should be based on an individual's running mechanics. If a mechanical analysis is not available, footwear recommendations can be based empirically on the individual's arch type.
Corticosteroids Reduce the Tensile Strength of Isolated Collagen Fascicles
Authors: Haraldsson Bjarki Thor , Langberg Henning , Aagaard Per , Zuurmond Anne-Marie , van El Benno , DeGroot Jeroen , Kjær Michael , Magnusson S. Peter
Published: August 2006

Background

Overuse tendon injuries are frequent. Corticosteroid injections are commonly used as treatment, although their direct effects on the material properties of the tendon are poorly understood.

Purpose

To examine the influence of corticosteroids on the tensile strength of isolated collagen fascicles.

Study Design

Controlled laboratory study.

Methods

Single strands (300-500 [.mu]m) of rat-tail collagen fascicles were incubated in either high (1 mL of 40 mgmL-1 mixed with 0.5 mL saline 9%) or low (1 mL of 40 mgmL-1 mixed with 2 mL saline 9%) concentration of methylprednisolone acetate (Depomedrol) for 3 or 7 days, while the control segment from the same fascicle was kept in saline (N = 64). After the incubation period, the fascicles underwent displacement to failure in a mechanical test rig at 0.13 mm/s, and thereafter hydroxylysyl pyridinoline and lysyl pyridinoline cross-link content was evaluated in a high-performance liquid chromatography system. Data for each group were analyzed with a 2-way analysis of variance (time × incubation) for ultimate stress (mean ± standard deviation).

Results

In the high-concentration groups, strength was reduced after 3 (16.6 ± 4.6 MPa) and 7 (8.6 ± 1.7 MPa) days compared to the controls (30.2 ± 5.0 MPa and 25.6 ± 4.6 MPa, respectively; P <. 05). In the low-concentration groups, strength was reduced after 3 (12.0 ± 3.1 MPa) and 7 days (10.9 ± 2.5 MPa) compared to the controls (31.5 ± 5.0 MPa and 32.4 ± 5.6 MPa, respectively; P <. 05). The amount of cross-linking was unaffected by the intervention.

Conclusion

Data show that the tensile strength of isolated fascicles is markedly reduced after 3-and 7-day incubation in both high and low concentration of corticosteroids, although the observed effect on whole tendon remains unknown.

Clinical Relevance

Corticosteroids may weaken specific regions of the injected tendon and leave it more prone to rupture. This weakening effect is manifested in the individual collagen fascicles that constitute the tendon.
Long–term Results of Arthroscopic Bankart Repair with a Bioabsorbable Tack
Authors: Marquardt Björn , Witt Kai–Axel , Götze Christian , Liem Dennis , Steinbeck Jörn , Pötzl Wolfgang
Published: August 2006

Background

Short-term to midterm data are available on arthroscopic shoulder stabilization using bioabsorbable tacks or suture anchors. It remains unknown whether these techniques can equal the success of open Bankart repair in the long term.

Purpose

To assess the long-term outcome of arthroscopic Bankart repair using bioabsorbable tacks in patients with traumatic anterior shoulder instability with a minimum follow-up of 7 years.

Study Design

Case series; Level of evidence, 4.

Methods

Treatment outcomes were determined prospectively according to the Rowe score and retrospectively according to the Constant and American Shoulder and Elbow Surgeons scores. Included in this study were 18 consecutive patients with a mean age of 26.8 years (range, 16-62 years) who underwent arthroscopic Bankart repair using bioabsorbable tacks for traumatic anterior shoulder instability. The study group consisted of 14 male and 4 female patients. The mean follow-up was 8.7 years (range, 7.0-9.8 years).

Results

One patient had recurrent dislocations requiring further surgery, for an overall failure rate of 5.6%. An additional patient had 1 traumatic subluxation episode within the first postoperative year that did not recur. According to the Rowe score, which increased to 90.3 (17.8) from 32.8 (8.3) points preoperatively, 15 patients (83.3%) achieved a good or excellent result. The mean Constant score was 91.3 (SD, 6.9) points, and the mean American Shoulder and Elbow Surgeons score was 92.1 (SD, 6.9) points postoperatively. A return to the preinjury level of sports competition was reported by 64% of patients. No signs of synovitis occurred in any patient postoperatively.

Conclusion

Arthroscopic Bankart repair for the treatment of recurrent traumatic anterior shoulder instability repair using bioabsorbable tacks offers reliable results with respect to failure rate, range of motion, and shoulder function during a minimum follow- up of 7.0 years. In contrast to previous reports on arthroscopic Bankart repair, results did not deteriorate during follow-up.
Medial Ulnar Collateral Ligament Reconstruction of the Elbow in Throwing Athletes
Authors: Dodson Christopher C. , Thomas Adrian , Dines Joshua S. , Nho Shane J. , Williams Riley J. , Altchek David W.
Published: August 2006

Background

Medial ulnar collateral ligament insufficiency of the elbow can be a devastating injury in the throwing athlete. Reconstruction of the medial ulnar collateral ligament was initially described by Jobe and associates; good clinical results have been described after this procedure. The authors' experience with this technique raised several concerns, and thus the “docking” procedure was developed as an alternative method for medial ulnar collateral ligament reconstruction of the elbow. The early results of the docking technique were good. The authors wish to investigate the intermediate-term clinical results of this method in a large group of athletes.

Hypothesis

The docking technique can return overhead-throwing athletes to sport with minimal perioperative morbidity.

Study Design

Case series; Level of evidence, 4.

Methods

During a 3-year period, 100 consecutive overhead-throwing athletes were treated with surgical reconstruction using the docking technique. The inclusion criteria were as follows: (1) a history of medial elbow pain that prevented throwing, (2) a preoperative standard noncontrast magnetic resonance image demonstrating medial ulnar collateral ligament injury, (3) clinically apparent medial ulnar collateral ligament insufficiency, and (4) an overhead-throwing athlete. At the time of surgery, all patients underwent routine arthroscopic assessment. The ulnar nerve was transposed in 22 cases. The mean follow-up was 36 months (range, 24-60 months).

Results

Ninety of 100 (90%) patients were able to compete at the same or a higher level than before medial ulnar collateral ligament injury for more than 12 months as noted at the follow-up interval; 7 patients were able to compete at a lower level. Only 3 patients suffered postoperative complications.

Conclusion

The docking technique reliably returns athletes to competitive throwing with a low perioperative morbidity.