bluuebunny/crossref_metadata_2025 huggingface dataset:
The Knowledge Economy
Authors: Powell Walter W. , Snellman Kaisa
Published: July 2004

We define the knowledge economy as production and services based on knowledge-intensive activities that contribute to an accelerated pace of technical and scientific advance, as well as rapid obsolescence. The key component of a knowledge economy is a greater reliance on intellectual capabilities than on physical inputs or natural resources. We provide evidence drawn from patent data to document an upsurge in knowledge production and show that this expansion is driven by the emergence of new industries. We then review the contentious literature that assesses whether recent technological advances have raised productivity. We examine the debate over whether new forms of work that embody technological change have generated more worker autonomy or greater managerial control. Finally, we assess the distributional consequences of a knowledge-based economy with respect to growing inequality in wages and high-quality jobs.
Narrative Explanation: An Alternative to Variable-Centered Explanation?
Authors: Abell Peter
Published: July 2004

The nature of narrative explanations is explored as an alternative to the better established variable-centered explanations. Narratives are conceived as di-graphs where the nodes are states of the world and the arcs are actions (causes). Comparative narratives are understood as mappings between di-graphs. Ethnographic and historical explanations, where the number of cases is small and causality complex, may depend upon a narrative depiction.
Comparative-Historical Methodology
Authors: Mahoney James
Published: July 2004

The last decade featured the emergence of a significant and growing literature concerning comparative-historical methods. This literature offers methodological tools for causal and descriptive inference that go beyond the techniques currently available in mainstream statistical analysis. In terms of causal inference, new procedures exist for testing hypotheses about necessary and sufficient causes, and these procedures address the skepticism that mainstream methodologists may hold about necessary and sufficient causation. Likewise, new techniques are available for analyzing hypotheses that refer to complex temporal processes, including path-dependent sequences. In the area of descriptive inference, the comparative-historical literature offers important tools for concept analysis and for achieving measurement validity. Given these contributions, comparative-historical methods merit a central place within the general field of social science methodology.
Explaining Criminalization: From Demography and Status Politics to Globalization and Modernization
Authors: Jenness Valerie
Published: July 2004

Organizing scholarship both chronologically and thematically, this article provides a review and critical evaluation of the literature that examines factors influencing criminalization. The first part of the paper examines three streams of inquiry and theorizing: (a) classic work that has shaped decades of scholarship on criminalization by focusing on the relationship between demographic changes, material and symbolic politics, and the emergence of criminal law; (b) contemporary work that unpacks the nature of the relationship between organizational, social movement, and state-related factors that structure and mediate the outcome of definitional and political processes involved in efforts to criminalize elements of social life; and (c) more recent work that envisions criminalization as a social process intimately connected to, and indeed arguably derivative of, larger processes of institutionalization, globalization, and modernization. The discussion and conclusion section summarizes the consequences of these three streams of inquiry and theorizing for our collective understanding of the structures and processes that underlie criminalization. Thereafter, the article concludes with a proposed agenda for subsequent research on criminalization and related topics.
Gender and Work in Germany: Before and After Reunification
Authors: Rosenfeld Rachel A. , Trappe Heike , Gornick Janet C.
Published: July 2004

New state and market arrangements were twice imposed on the residents of the eastern part of Germany, once when Germany was divided in 1949 and again when it was reunified in 1990; these changes produced a unique natural experiment concerning the effect of policies and institutions on the gendered nature of work. This review synthesizes research on gender equality in paid and unpaid work in East versus West Germany during the decades immediately preceding and following reunification. We consider empirical evidence on gender equality in five major dimensions of work: the prevalence of labor market attachment, time spent in paid work, wages, employment sector and occupation, and time spent in unpaid work in the home. Taken together, developments across these dimensions suggest that, following reunification, the two parts of the country converged toward the gendered arrangement in which men are employed full-time and their female partners hold part-time jobs—with some evidence of continuing differences between East and West.
The Sociology of Property Rights
Authors: Carruthers Bruce G. , Ariovich Laura
Published: July 2004

Property rights matter for their effects on economic inequality and economic performance, and they unfold at the intersection of law, the state, politics, and the economy. Five dimensions of property are discussed: the objects of property (what can be owned), the subjects of property (who can own), the uses of property (what can be done with it), the enforcement of rights (how property rules are maintained), and the transfer of property (how property moves between different owners). We offer examples of how property rights systems vary along these dimensions and how they change over time. We illustrate the arguments with two contemporary empirical cases: the transition economies of Eastern and Central Europe, Russia, and China, and the transformation of intellectual property rights.
Advocacy Organizations in the U.S. Political Process
Authors: Andrews Kenneth T. , Edwards Bob
Published: July 2004

We examine scholarship on the role and influence of advocacy organizations in the U.S. political process. We identify common theoretical questions in the disconnected literatures on social movements, interest groups, and nonprofits, and we propose a unifying conceptual framework for examining advocacy organizations. Focusing on the post-1960s growth in advocacy organizations, we examine major organizational characteristics including organizational structures, membership and participation, resources, and interorganizational networks and coalitions. Our analysis of organizational influence focuses on five dimensions of the policy process: (a) agenda setting, (b) access to decision-making arenas, (c) achieving favorable policies, (d) monitoring and shaping implementation, and (e) shifting the long-term priorities and resources of political institutions. Finally, we identify recurrent theoretical and methodological problems, including the compartmentalization of research within disciplines, an overreliance on studies of large national organizations, a disproportionate focus on recruitment and selective incentives, and limited research on the influence of advocacy organizations. We conclude by highlighting productive pathways for future scholarship.
Consumers and Consumption
Authors: Zukin Sharon , Maguire Jennifer Smith
Published: July 2004

Consumption is a social, cultural, and economic process of choosing goods, and this process reflects the opportunities and constraints of modernity. Viewing consumption as an “institutional field,” the review suggests how consumption bridges economic and cultural institutions, large-scale changes in social structure, and discourses of the self. New technologies, ideologies, and delivery systems create consumption spaces in an institutional framework shaped by key social groups, while individual men and women experience consumption as a project of forming, and expressing, identity. Studying the institutional field requires research on consumer products, industries, and sites; on the role of consumption in constructing both the consuming subject and collective identity; and on historical transitions to a consumer society. Ethnography, interviews, and historical analysis show a global consumer culture fostered by media and marketing professionals yet subject to different local interpretations.
Endogenous Explanation in the Sociology of Culture
Authors: Kaufman Jason
Published: July 2004

This paper examines recent work in the sociology of culture devoted to providing endogenous explanations of cultural phenomena. The focus is on works that provide cultural explanations of cultural processes, as opposed to the social structural and “production of culture” explanations otherwise predominant in the literature. I examine three distinct approaches: a “post-hermeneutic” approach devoted not to the question of cultural interpretation but to the issue of subjects' manipulation of culture in the quest for meaning; a semiotic approach focused on the mechanics of symbol systems; and an ecological approach that emphasizes the role of competition and niche density in explaining both cultural stasis and change. The three approaches have in common a general lack of interest in traditional conceptions of meaning (verstehen), choosing instead to focus on issues related to the internal structure and dynamics of cultural expression. This marks a new opportunity for synthesis and exploration in a field traditionally devoted to extra-cultural explanation of cultural phenomena. Both endogenous and exogenous explanations are offered for the rise of this new trend in the sociology of culture.
Panel Models in Sociological Research: Theory into Practice
Authors: Halaby Charles N.
Published: July 2004

A selection of panel studies appearing in the American Sociological Review and the American Journal of Sociology between 1990 and 2003 shows that sociologists have been slow to capitalize on the advantages of panel data for controlling unobservables that threaten causal inference in observational studies. This review emphasizes regression methods that capitalize on the strengths of panel data for consistently estimating causal parameters in models for metric outcomes when measured explanatory variables are correlated with unit-specific unobservables. Both static and dynamic models are treated. Among the major subjects are fixed versus random effects methods, Hausman tests, Hausman-Taylor models, and instrumental variables methods, including Arrelano-Bond and Anderson-Hsaio estimation for models with lagged endogenous variables.
Reflections on a Half-Century of Organizational Sociology
Authors: Scott W. Richard
Published: July 2004

For the past half-century, the study of organizations has been an active area within sociology. I provide an overview of the emergence of this specialty during the second half of the twentieth century, its relation to the larger field of organization studies, and the important theoretical advances associated with the adoption of an open system framework during the 1960s. Among the recent trends I describe are changes in our conceptions of organization boundaries, strategies, and controls, and the beginning of a shift from an entity-based to a process-based view of organization. Evidence of success—the number of sociologists now employed in professional schools—simultaneously raises concerns about the source of future organizational sociologists.
Physical training may enhance β-cell function in type 2 diabetes
Authors: Dela Flemming , von Linstow Michael E. , Mikines Kári Joensen , Galbo Henrik
Published: July 2004

In healthy young subjects, training increases insulin sensitivity but decreases the capacity to secrete insulin. We studied whether training changes β-cell function in type 2 diabetic patients. Patients, stratified into “moderate” and “low” secretors according to individual C-peptide responses to an intravenous glucagon test, were randomly assigned to a training program [ergometer cycling 30–40 min/day, including at least 20 min at 75% maximum oxygen consumption (V̇o2 max), 5 days/wk for 3 mo] or a sedentary schedule. Before and after the intervention (16 h after last training bout), a sequential hyperglycemic (90 min at 11, 18, and 25 mM) clamp was performed. An intravenous bolus of 5 g of arginine was given at the end. Training increased V̇o2 max 17 ± 13% and decreased heart rate during submaximal exercise ( P < 0.05). During the 3 mo of sedentary lifestyle, insulin and C-peptide responses to the clamp procedures were unchanged in both moderate and low secretors. Likewise, no change in β-cell response was seen after training in the low secretors ( n = 5). In contrast, moderate secretors ( n = 9) showed significant increases in β-cell responses to 18 and 25 mM hyperglycemia and to arginine stimulation. Glucagon responses to arginine as well as measures of insulin sensitivity and Hb A1c levels were not altered by training. In conclusion, in type 2 diabetic patients, training may enhance β-cell function if the remaining secretory capacity is moderate but not if it is low. The improved β-cell function does not require changes in insulin sensitivity and Hb A1c concentration.
gp91phox-Dependent Expression of Platelet CD40 Ligand
Authors: Pignatelli P. , Sanguigni V. , Lenti L. , Ferro D. , Finocchi A. , Rossi P. , Violi F.
Published: July 2004

Background—

CD40 ligand (CD40L) expression on platelets is mediated by agonists, but the underlying mechanism is still unclear.

Methods and Results—

CD40L expression was measured in platelets from healthy subjects both with and without the addition of antioxidants or a phospholipase A2 (PLA2) inhibitor and in platelets from 2 patients with an inherited deficiency of gp91phox. Immunoprecipitation analysis was also performed to determine whether normal platelets showed gp91phox expression. Unlike catalase and mannitol, superoxide dismutase inhibited agonist-induced platelet CD40L expression in healthy subjects. Immunoprecipitation analysis also showed that platelets from healthy subjects expressed gp91phox. In 2 male patients with inherited gp91phox deficiency, collagen-, thrombin-, and arachidonic acid-stimulated platelets showed an almost complete absence of superoxide anion (O
2
−
) and CD40L expression. Incubation of platelets from healthy subjects with a PLA2 inhibitor almost completely prevented agonist-induced O
2
−
and CD40L expression.

Conclusions—

These data provide the first evidence that platelet CD40L expression occurs via arachidonic acid–mediated gp91phox activation.
Coronary Artery Spatial Distribution of Acute Myocardial Infarction Occlusions
Authors: Wang John C. , Normand Sharon-Lise T. , Mauri Laura , Kuntz Richard E.
Published: July 2004

Background—

Acute coronary occlusions leading to ST-segment elevation myocardial infarctions (STEMIs) are due primarily to rupture of atherosclerotic plaques. Present “vulnerable plaque” detection technology focuses on identifying individual plaques with no clear therapeutic plan beyond conventional risk factor reduction. We developed a spatial map of the distribution of acute coronary occlusions to test our hypothesis that plaque ruptures do not occur uniformly throughout the coronary tree.

Methods and Results—

We analyzed 208 consecutive patients who presented to the Brigham and Women’s Hospital with STEMI and mapped the location of the acute coronary occlusion. These occlusions were not uniformly distributed throughout each of the major epicardial coronary arteries but tended to cluster within the proximal third of each of the vessels (right coronary artery,
P
=0.001; left anterior descending artery,
P
=0.003; left circumflex artery,
P
=0.001). Furthermore, Poisson regression showed that for each 10-mm increase in distance from the ostium, the risk of an acute coronary occlusion was significantly decreased by 13% in the right coronary artery, 30% in the left anterior descending artery, and 26% in the left circumflex artery.

Conclusions—

Acute coronary occlusions leading to STEMI tend to cluster in predictable “hot spots” within the proximal third of the coronary arteries. Identification of these high-risk zones for acute coronary occlusions will lead to future advances in vulnerable plaque detection technology and potentially locally directed preventive strategies.
Evaluation and Clinical Implications of Aortic Valve Calcification Measured by Electron-Beam Computed Tomography
Authors: Messika-Zeitoun David , Aubry Marie-Christine , Detaint Delphine , Bielak Lawrence F. , Peyser Patricia A. , Sheedy Patrick F. , Turner Stephen T. , Breen Jerome F. , Scott Christopher , Tajik A. Jamil , Enriquez-Sarano Maurice
Published: July 2004

Background—

Electron-beam computed tomography (EBCT) is used to measure coronary calcification but not for aortic valve calcification (AVC). Its accuracy, association with aortic stenosis (AS) severity, and diagnostic and prognostic value with respect to AVC are unknown.

Methods and Results—

In 30 explanted aortic valves, the AVC score by EBCT (1125±1294 Agatston units [AU]) showed a strong linear correlation (
r
=0.96,
P
<0.0001) with valvular calcium weight (653±748 mg) by pathology that allowed estimation of calcium weight as AVC score/1.7, with a small standard error of the estimate (53 mg). In 100 consecutive clinical patients, we measured AVC by EBCT and AS severity by echocardiographic aortic valve area (AVA). The AVC score was 1316±1749 AU (range 0 to 7226 AU). Intraobserver and interobserver variabilities were excellent (4±4% and 4±10%, respectively). AVC and AVA were strongly associated (
r
=0.79,
P
<0.0001) but had a curvilinear relationship that suggested that AVC and AVA provide complementary information. AVC score ≥1100 AU provided 93% sensitivity and 82% specificity for diagnosis of severe AS (AVA <1 cm
2
), with a receiver operator characteristic curve area of 0.89. AVC assessment by echocardiography was often more severe than by EBCT (
P
<0.0001). During follow-up, 22 patients either died, developed heart failure, or required surgery. With adjustment for age, sex, symptoms, ejection fraction, and AVA, the AVC score was independently predictive of event-free survival (risk ratio 1.06 per 100-AU increment [1.02 to 1.10],
P
<0.001), even after adjustment for echocardiographic calcifications.

Conclusions—

AVC is accurately and reproducibly measured by EBCT and shows a strong association and diagnostic value for severe AS. The curvilinear relationship between AVC and AVA suggests these measures are complementary, and indeed, AVC provides independent outcome information. Thus, AVC is an important measurement in the evaluation of patients with AS.
Aldosterone Directly Induces Myocyte Apoptosis Through Calcineurin-Dependent Pathways
Authors: Mano Akiko , Tatsumi Tetsuya , Shiraishi Jun , Keira Natsuya , Nomura Tetsuya , Takeda Mitsuo , Nishikawa Susumu , Yamanaka Satoshi , Matoba Satoaki , Kobara Miyuki , Tanaka Hideo , Shirayama Takeshi , Takamatsu Tetsuo , Nozawa Yoshihisa , Matsubara Hiroaki
Published: July 2004

Background—

Aldosterone has recently attracted considerable attention for its involvement in the pathophysiology of heart failure, in which apoptotic cell loss plays a critical role. This study examined whether aldosterone directly induces myocyte apoptosis via its specific receptors.

Methods and Results—

Neonatal rat cardiac myocytes were exposed to aldosterone (10
−8
to 10
−5
mol/L). Nuclear staining with Hoechst 33258 showed that aldosterone induced myocyte apoptosis in a dose- and time-dependent fashion. Treatment of myocytes with 10
−5
mol/L aldosterone significantly increased the percentage of apoptosis (15.5±1.4%) compared with serum-deprived control (7.3±0.6%). Radio ligand binding assay revealed the existence of plasma membrane receptor with high affinity (
K
d
, 0.2 nmol/L) for aldosterone in cardiac myocytes but not in fibroblasts. Aldosterone rapidly (≈30 seconds) mobilized [Ca
2+
]
i
that was blocked by neomycin. Aldosterone induced dephosphorylation of the proapoptotic protein Bad, enhancement of mitochondrial permeability transition, decrease in mitochondrial membrane potential, and release of cytochrome c from the mitochondria into the cytosol with concomitant activation of caspase-3. These effects of aldosterone were inhibited by concurrent treatment with either an L-type Ca
2+
channel antagonist, nifedipine, or inhibitors for the Ca
2+
-dependent phosphatase calcineurin, cyclosporin A and FK506.

Conclusions—

The present study demonstrates for the first time that the specific plasma membrane receptor (coupled with phospholipase C) for aldosterone is present on cardiac myocytes and that aldosterone accelerates the mitochondrial apoptotic pathway through activation of calcineurin and dephosphorylation of Bad, suggesting that the proapoptotic action of aldosterone may directly contribute to the progression of heart failure.
Treatment of Left Anterior Descending Coronary Artery Disease With Sirolimus-Eluting Stents
Authors: Sawhney Neil , Moses Jeffrey W. , Leon Martin B. , Kuntz Richard E. , Popma Jeffrey J. , Bachinsky William , Bass Theodore , DeMaio Samuel , Fry Edward , Holmes David R. , Teirstein Paul S.
Published: July 2004

Background—

Revascularization strategies often hinge on the presence and degree of left anterior descending coronary artery (LAD) stenosis. A decision for bypass surgery is often based on the durability of surgical LAD revascularization compared with percutaneous approaches. By decreasing restenosis, drug-eluting stents may have reduced the “reintervention gap” between surgery and percutaneous intervention, making the percutaneous route preferable.

Methods and Results—

Of the 1101 patients in the SIRIUS trial, 459 with an LAD stenosis were randomized to percutaneous intervention with either sirolimus-eluting or bare-metal stents. Baseline demographic, clinical, and angiographic data were obtained. Patients had 1-year clinical and 8-month angiographic follow-up. Baseline characteristics were similar in both groups. The majority of lesions were tubular type B lesions (69.7%) with a mean diameter of 2.73 mm and a mean length of 14.0 mm. The binary in-stent restenosis rate was 2% for the sirolimus stent group and 41.6% for the bare-metal arm (relative risk, 0.05; 95% CI, 0.02 to 0.1;
P
<0.001). One-year major adverse events (defined as cardiac death, Q-wave and non–Q-wave myocardial infarction, or target vessel revascularization) was decreased 59% in the sirolimus-stent group (9.8% versus 24.9%; relative risk, 0.39; 95% CI, 0.26 to 0.61;
P
<0.001). Subgroup analysis of 135 patients with proximal LAD lesions showed similar benefits. In-stent restenosis was 0 in the proximal LAD sirolimus-eluting group (n=67), compared with 38% in the bare-metal arm (n=68), and major adverse events demonstrated a similar trend, with a 50% decrease compared with control patients (10.4% versus 20.6%,
P
=NS).

Conclusions—

Sirolimus-eluting stents significantly decrease revascularization rates in LAD lesions. At 1 year, sirolimus-eluting stent revascularization rates are comparable to historic single vessel bypass surgery revascularization rates.
Association of Atrial Fibrillation and Obstructive Sleep Apnea
Authors: Gami Apoor S. , Pressman Gregg , Caples Sean M. , Kanagala Ravi , Gard Joseph J. , Davison Diane E. , Malouf Joseph F. , Ammash Naser M. , Friedman Paul A. , Somers Virend K.
Published: July 2004

Background—

Obstructive sleep apnea (OSA) is associated with recurrent atrial fibrillation (AF) after electrocardioversion. OSA is highly prevalent in patients who are male, obese, and/or hypertensive, but its prevalence in patients with AF is unknown.

Methods and Results—

We prospectively studied consecutive patients undergoing electrocardioversion for AF (n=151) and consecutive patients without past or current AF referred to a general cardiology practice (n=312). OSA was diagnosed with the Berlin questionnaire, which is validated to identify patients with OSA. We also assessed its accuracy compared with polysomnography in a sample of the study population. Groups were compared with the 2-tailed
t
, Wilcoxon, and χ
2
tests. Logistic regression modeled the association of AF and OSA after adjustment for relevant covariates. Patients in each group had similar age, gender, body mass index, and rates of diabetes, hypertension, and congestive heart failure. The questionnaire performed with 0.86 sensitivity, 0.89 specificity, and 0.97 positive predictive value in our sample. The proportion of patients with OSA was significantly higher in the AF group than in the general cardiology group (49% versus 32%,
P
=0.0004). The adjusted odds ratio for the association between AF and OSA was 2.19 (95% CI 1.40 to 3.42,
P
=0.0006).

Conclusions—

The novel finding of this study is that a strong association exists between OSA and AF, such that OSA is strikingly more prevalent in patients with AF than in high-risk patients with multiple other cardiovascular diseases. The coinciding epidemics of obesity and AF underscore the clinical importance of these results.
CD34
+
and Endothelial Progenitor Cells in Patients With Various Degrees of Congestive Heart Failure
Authors: Valgimigli Marco , Rigolin Gian Matteo , Fucili Alessandro , Porta Matteo Della , Soukhomovskaia Olga , Malagutti Patrizia , Bugli Anna Maria , Bragotti Letizia Zenone , Francolini Gloria , Mauro Endri , Castoldi Gianluigi , Ferrari Roberto
Published: July 2004

Background—

Peripheral blood CD34
+
cells and circulating endothelial progenitor cells (EPCs) increase in myocardial infarction and vascular injuries as a reflection of endothelial damage. Despite the occurrence of endothelial dysfunction in heart failure (HF), no data are available on EPC mobilization in this setting. We investigated the pattern of CD34
+
cells and EPC mobilization during HF and their correlation with the severity and origin of the disease.

Methods and Results—

Peripheral blood CD34
+
cells (n=91) and EPCs (n=41), assessed both as CD34
+
cells coexpressing AC133 and vascular endothelial growth factor (VEGF) receptor-2 and as endothelial colony-forming units, were studied in HF patients (mean age 67±11 years) and 45 gender- and age-matched controls. Tumor necrosis factor-α (TNF-α) and its receptors (sTNFR-1 and sTNFR-2), VEGF, stromal derived factor-1 (SDF-1), granulocyte-colony stimulating factor (G-CSF), and B-type natriuretic peptide were also measured. CD34
+
cells, EPCs, TNF-α and receptors, VEGF, SDF-1, and B-type natriuretic peptide were increased in HF. CD34
+
cells and EPCs were inversely related to functional class and to TNF-α, being decreased in New York Heart Association class IV compared with class I and II and controls. No role was found for the origin of the disease.

Conclusions—

CD34
+
cells and EPC mobilization occurs in HF and shows a biphasic response, with elevation and depression in the early and advanced phases, respectively. This could be related to the myelosuppressive role of TNF-α.
Identification by a Differential Proteomic Approach of Heat Shock Protein 27 as a Potential Marker of Atherosclerosis
Authors: Martin-Ventura Jose Luis , Duran Mari Carmen , Blanco-Colio Luis Miguel , Meilhac Olivier , Leclercq Anne , Michel Jean-Baptiste , Jensen Ole N. , Hernandez-Merida Sergio , Tuñón José , Vivanco Fernando , Egido Jesús
Published: July 2004

Background—

We hypothesized that normal and pathological vessel walls display a differential pattern of secreted proteins. We have recently set up the conditions for comparing secretomes from carotid atherosclerotic plaques and control arteries using a proteomic approach to assess whether differentially secreted proteins could represent markers for atherosclerosis.

Methods and Results—

Normal endartery segments and different regions of endarterectomy pieces (noncomplicated/complicated plaques) were incubated in protein-free medium, and the released proteins were analyzed by 2D electrophoresis (2-DE). Among the differently secreted proteins, we have identified heat shock protein-27 (HSP27). Surprisingly, compared with control arteries, HSP27 release was drastically decreased in atherosclerotic plaques and barely detectable in complicated plaque supernatants. HSP27 was expressed primarily by intact vascular cells of normal arteries and carotid plaques (immunohistochemistry). Plasma detection of soluble HSP27 showed that circulating HSP27 levels are significantly decreased in the blood of patients with carotid stenosis relative to healthy subjects (0.19 [0.1 to 1.95] versus 83 [71.8 to 87.8]) ng/mL,
P
<0.0001).

Conclusions—

HSP27 secretion is decreased in complicated atherosclerotic plaques, and sHSP27 plasma levels are decreased in atherosclerotic patients compared with healthy subjects. Plasma sHSP27 levels could be a potential index of atherosclerosis, although further validation is needed in large patient cohorts.
Association of Anti–Heat Shock Protein 65 Antibodies With Development of Postoperative Atrial Fibrillation
Authors: Mandal Kaushik , Jahangiri Marjan , Mukhin Michael , Poloniecki Jan , Camm A. John , Xu Qingbo
Published: July 2004

Background—

Atrial fibrillation (AF) is a frequently encountered arrhythmia after cardiac surgery, but its underlying mechanisms are still unclear. We hypothesize that autoimmune and inflammatory responses against heat shock protein 65 (HSP65) may be involved and hence examined the relationship between HSP65 autoantibodies and occurrence of postoperative AF.

Methods and Results—

A prospective study of 329 patients undergoing elective primary CABG was undertaken. Cardiovascular risk factors, ECG characteristics, medications, and intraoperative and postoperative features were documented. Anti-HSP65 antibodies and C-reactive protein levels were measured in all preoperative blood samples with ELISA. Postoperative AF was defined as the characteristic arrhythmia, lasting for at least 15 minutes and confirmed on 12-lead ECG and occurring within the first postoperative week. This occurred in 62 patients (19%). In univariate analysis, HSP65 antibodies were significantly higher in patients with postoperative AF (
P
=0.02). History of previous myocardial infarction, duration of bypass, number of distal anastomosis, and duration of ventilation were also associated with AF (
P
<0.05), but C-reactive protein levels were not (
P
=0.13). Multivariate analysis confirmed the positive association of HSP65 antibodies with postoperative AF (OR, 1.41;
P
=0.04) independent of age, sex, other cardiovascular risk factors, severity of coronary artery disease, duration of ventilation, duration of bypass, and left ventricular function.

Conclusions—

We report a novel association between anti-HSP65 antibodies and occurrence of postoperative AF, indicating a possible role for antibody-mediated immune response in its pathogenesis.
Bradykinin Regulates Cyclooxygenase-2 in Rat Renal Thick Ascending Limb Cells
Authors: Rodriguez Jorge A. , Vio Carlos P. , Pedraza Paulina L. , McGiff John C. , Ferreri Nicholas R.
Published: July 2004

Cyclooxygenase-2 (COX-2) is constitutively expressed in a subset of thick ascending limb cells in the cortex and medulla and increases when the renin-angiotensin and kallikrein-kinin systems are activated. Although the contribution of angiotensin II to the regulation of COX-2 is known, the effects of bradykinin on COX-2 expression have not been determined in this nephron segment. We evaluated expression of B2 bradykinin receptors in thick ascending limb cells containing COX-2 and the effect of bradykinin on COX-2 expression in primary cultured medullary thick ascending cells. The presence of B2 receptors was studied in renal sections by immunohistochemistry with antibodies against B2, COX-2, and Tamm-Horsfall glycoprotein. B2 receptors were detected on the apical and basolateral portion of the thick ascending cells. These cells also contained COX-2, suggesting that COX-2 expression may be regulated via B2 receptor. Incubation of cultured medullary thick ascending cells with bradykinin (10
−7
to 10
−5
mol/L) induced a significant increase on COX-2 protein expression. Maximal expression of COX-2 was observed 4 hours after exposure to bradykinin (10
−7
mol/L), effect abolished by a B2 receptor antagonist (HOE-140; 10
−6
mol/L). Prostaglandin E
2
production increased when these cells were challenged with bradykinin for 4 hours, indicating that COX-2 was enzymatically active. We have demonstrated (1) the presence of B2 receptors in thick ascending limb cells expressing COX-2 and (2) the stimulatory effect of bradykinin on COX-2 protein expression, via B2 receptors, in cultured medullary thick ascending cells. We suggest that bradykinin can affect ion transport in the thick ascending limb via a COX-2–mediated mechanism.
Effect of Angiotensin-Converting Enzyme Inhibition on Survival in 3773 Chinese Type 2 Diabetic Patients
Authors: So Wing Yee , Ozaki Risa , Chan Norman N. , Tong Peter C.Y. , Ho Chung Shun , Lam Christopher W.K. , Ko Gary T.C. , Chow Chun Chung , Chan Wing Bun , Ma Ronald C.W. , Chan Juliana C.N.
Published: July 2004

We assessed the effects of angiotensin-converting enzyme (ACE) inhibition on survival and cardiorenal outcomes in a consecutive cohort of Chinese type 2 diabetic patients with varying degree of albuminuria, ranging from normoalbuminuria to macroalbuminuria. A total of 3773 consecutive Chinese type 2 diabetic patients were followed prospectively for a mean period of 35.8 months. Clinical end points included all-cause mortality, with cardiovascular end point defined as first hospitalization because of ischemic heart disease, congestive heart failure, revascularization procedures, or cerebrovascular accident as well as renal end point defined as dialysis, doubling of baseline plasma creatinine, or plasma creatinine ≥500 μmol/L. The use of ACE inhibitor was 26.3% in normoalbuminuric (NA), 70.1% in microalbuminuric (MI), and 82.6% in macroalbuminuric (MA) groups. Albuminuria was a major predictor for all-cause mortality with 4-fold difference between NA and MA patients. The 7-year cumulative mortality rate was 7.1%, 10.8%, and 21.7% in the NA, MI, and MA groups, respectively. The use of ACE inhibition was associated with significant reduction of mortality (hazard ratio 0.41 and 95% confidence interval, 0.29, 0.58) in the entire group and was most evident in high-risk patients who had cardiorenal complications or retinopathy at baseline for all albuminuric groups (NA 0.76 [0.31,1.87]; MI 0.32 [0.16, 0.65]; and MA 0.20 [0.13, 0.33]). The prognostic value of albuminuria for death in type 2 diabetes and the beneficial effects of ACE inhibitors in Chinese type 2 diabetic patients with micro- or macroalbuminuria has been confirmed. The effects of ACE inhibitors in type 2 diabetic patients with normoalbuminuria require further evaluation.
Impaired Endothelial Release of Tissue-Type Plasminogen Activator in Patients With Chronic Kidney Disease and Hypertension
Authors: Hrafnkelsdóttir Thórdís , Ottosson Pia , Gudnason Thorarinn , Samuelsson Ola , Jern Sverker
Published: July 2004

We have shown that the capacity for local release of tissue-type plasminogen activator (tPA) from the vascular endothelium is impaired in patients with primary hypertension. Because this response is an important protective mechanism against intravascular clotting, we investigated whether this system is also defective in patients with advanced chronic kidney disease and hypertension. Nine nondiabetic nonsmoking men with chronic kidney disease (glomerular filtration rate 11 to 28 mL/min×1.73 m
2
; aged 33 to 75 years) were compared with age-matched healthy controls. Intraarterial infusions of desmopressin, methacholine, and sodium nitroprusside were given locally in the brachial artery. Forearm blood flow was measured by venous occlusion plethysmography and blood collected repeatedly during the desmopressin infusion for determination of stimulated net and total cumulated release of tPA. The maximal release rate of active tPA (
P
<0.05) and the capacity for acute tPA release were markedly impaired in the renal patients as compared with healthy subjects (ANOVA,
P
=0.013). Accordingly, the accumulated release of tPA was 1905 (SEM 366) and 3387 (718) ng/L tissue, respectively (
P
<0.05). However, there were no significant differences in vasodilator responses between the groups. Thus, patients with advanced chronic kidney disease and hypertension have a markedly impaired capacity for acute release of tissue plasminogen activator, despite preserved endothelium-dependent vasodilation. This defect may contribute to a defective local defense against arterial thrombosis.
Scalable 3D Representation for 3D Video in a Large-Scale Space
Authors: Kitahara Itaru , Ohta Yuichi
Published: July 2004

In this paper, we introduce our research aimed at realizing a 3D video system in a very large-scale space such as a soccer stadium or concert hall. We propose a method for describing the shape of a 3D object with a set of planes in order to effectively synthesize a novel view of the object. The most effective layout of the planes can be determined based on the relative locations of the observer's viewing position, multiple cameras, and 3D objects. We describe a method for controlling the LOD of the 3D representation by adjusting the planes' orientation, interval, and resolution. The data size of the 3D model and the processing time can be reduced drastically. The effectiveness of the proposed method is demonstrated by our experimental results.
System and Interface Framework for SCAPE as a Collaborative Infrastructure
Authors: Hua Hong , Brown Leonard D. , Gao Chunyu
Published: July 2004

We have developed a multi-user collaborative infrastructure, SCAPE (an acronym for Stereoscopic Collaboration in Augmented and Projective Environments), which is based on recent advancement in head-mounted projective display (HMPD) technology. SCAPE combines the functionalities of an interactive workbench and a room-sized immersive display to concurrently create both exocentric and egocentric perspectives. SCAPE intuitively provides a shared space in which multiple users can simultaneously interact with a 3D synthetic environment from their individual viewpoints, and each user has concurrent access to the environment from multiple perspectives at multiple scales. SCAPE also creates a platform to merge the traditionally separate paradigms of virtual and augmented realities. In this paper, we discuss the design principles we have followed to conceptualize the SCAPE system and briefly summarize SCAPE's hardware implementation. Furthermore, we discuss in detail the high-level design and implementation of the SCAPE architecture, and present a set of unique widget interfaces currently available in our implementation that enable and facilitate interaction and cooperation. Finally, we demonstrate SCAPE's unique visualization and interface capabilities via a testbed application— Aztec Explorer.
A small proportion of mesenchymal stem cells strongly expresses functionally active CXCR4 receptor capable of promoting migration to bone marrow
Authors: Wynn Robert F. , Hart Claire A. , Corradi-Perini Carla , O'Neill Liam , Evans Caroline A. , Wraith J. Ed , Fairbairn Leslie J. , Bellantuono Ilaria
Published: July 2004

Homing of bone marrow stromal cells (MSCs) to bone and bone marrow after transplantation, important for the correction of conditions such as metabolic storage disorders, can occur but with poor efficiency. Substantial improvements in engraftment will be required in order to derive a clinical benefit from MSC transplantation. Chemokines are the most important factors controlling cellular migration. Stromal-derived factor-1 (SDF-1) has been shown to be critical in promoting the migration of cells to the bone marrow, via its specific receptor CXCR4. The aim of our study was to investigate CXCR4 expression on MSCs and its role in mediating migration to bone marrow. We show that CXCR4, although present at the surface of a small subset of MSCs, is important for mediating specific migration of these cells to bone marrow. (Blood. 2004; 104:2643-2645)
Adolescent Brain Development: A Period of Vulnerabilities and Opportunities. Keynote Address
Authors: DAHL RONALD E.
Published: July 2004

Abstract: This article introduces and summarizes the goals of the symposium. It also provides an overview of a conceptual framework for understanding adolescence, which emphasizes how the very nature of this developmental transition requires an interdisciplinary approach—one that focuses on brain/behavior/social‐context interactions during this important maturational period. More specifically it describes a set of neurobehavioral changes that appear to be linked to pubertal development, which appear to have a significant effect on motivation and emotion, and considers these puberty‐specific changes in affect in relation to a much larger set of developmental changes in adolescence. This framework is used to argue for the need for a transdisciplinary dialogue that brings together work in several areas of neuroscience (including animal models) and normal development with clinical and social policy research aimed at early intervention and prevention strategies.
Adolescent Brain Development and Animal Models
Authors: SPEAR LINDA PATIA
Published: July 2004

Abstract: Research examining brain development during adolescence is escalating rapidly along multiple dimensions, as illustrated by the remarkable diversity of trans‐disciplinary work shown in this symposium. Ontogenetic transitions characteristics of adolescence are common among mammalian species. Although no other species demonstrates the full complexity of brain and behavioral function seen in human adolescents, adolescence appears to be a highly conserved developmental stage, its characteristics sculpted to meet common evolutionary pressures that include the avoidance of inbreeding at this time of sexual emergence. Numerous similarities are found between human adolescents and adolescents of other species in terms of developmental history and genetic constraints, as well as neurobehavioral and physiological characteristics. These similarities provide face and construct validity to support use of animal models as tools for the study of adolescence and the unique opportunities and vulnerabilities afforded by this developmental transition.
Limbic Corticostriatal Systems and Delayed Reinforcement
Authors: CARDINAL RUDOLF N. , WINSTANLEY CATHARINE A. , ROBBINS TREVOR W. , EVERITT BARRY J.
Published: July 2004

Abstract: Impulsive choice, one aspect of impulsivity, is characterized by an abnormally high preference for small, immediate rewards over larger delayed rewards, and can be a feature of adolescence, but also attention‐deficit/hyperactivity disorder (ADHD), addiction, and other neuropsychiatric disorders. Both the serotonin and dopamine neuromodulator systems are implicated in impulsivity; manipulations of these systems affect animal models of impulsive choice, though these effects may depend on the receptor subtype and whether or not the reward is signaled. These systems project to limbic cortical and striatal structures shown to be abnormal in animal models of ADHD. Damage to the nucleus accumbens core (AcbC) causes rats to exhibit impulsive choice. These rats are also hyperactive, but are unimpaired in tests of visuospatial attention; they may therefore represent an animal model of the hyperactive‐impulsive subtype of ADHD. Lesions to the anterior cingulate or medial prefrontal cortex, two afferents to the AcbC, do not induce impulsive choice, but lesions of the basolateral amygdala do, while lesions to the orbitofrontal cortex have had opposite effects in different tasks measuring impulsive choice. In theory, impulsive choice may emerge as a result of abnormal processing of the magnitude of rewards, or as a result of a deficit in the effects of delayed reinforcement. Recent evidence suggests that AcbC‐lesioned rats perceive reward magnitude normally, but exhibit a selective deficit in learning instrumental responses using delayed reinforcement, suggesting that the AcbC is a reinforcement learning system that mediates the effects of delayed rewards.
High‐Risk Behavior during Adolescence: Comments on Part I
Authors: BARDO MICHAEL T.
Published: July 2004

Abstract: Cardinal and Steinberg provide evidence from both laboratory animal and human studies indicating that behavior is controlled by two distinct brain systems, one activational and the other inhibitory. This conceptual framework continues to be a useful integrative framework in developmental neurobiology and psychology. Despite the conceptual framework that posits a two‐system control of high‐risk behavior, it is notable that the bulk of research related to this topic has focused on one system in isolation from the other. Since the activational and inhibitory systems are constructs that are amenable to investigation using both laboratory animals and human subjects, it seems that a fruitful avenue for future interdisciplinary research would be to ascertain the interactive effect of these systems across the periadolescent period.
Postnatal Development of Prefrontal Inhibitory Circuits and the Pathophysiology of Cognitive Dysfunction in Schizophrenia
Authors: LEWIS DAVID A. , CRUZ DIANNE , EGGAN STEPHEN , ERICKSON SUSAN
Published: July 2004

Abstract: The typical appearance of the clinical features of schizophrenia during late adolescence or early adulthood suggests that adolescence‐related neurodevelopmental events may contribute to the pathophysiology of this disorder. Here the role that GABA‐mediated inhibition in the dorsal lateral prefrontal cortex (DLPFC) plays in regulating working memory, a core cognitive process that matures late and that is disturbed in schizophrenia, is reviewed. Recent studies are summarized that demonstrate (1) that certain pre‐ and postsynaptic markers of GABA neurotransmission in the monkey DLPFC exhibit striking changes during adolescence, and (2) that these same markers are markedly altered in the DLPFC of subjects with schizophrenia. The implications of these findings for treatment and prevention strategies are discussed.
Puberty, Ovarian Steroids, and Stress
Authors: YOUNG ELIZABETH A. , ALTEMUS MARGARET
Published: July 2004

Abstract: Puberty is accompanied by a number of changes, among them increased risk for development of major depression. The most common etiology of major depression is stressful life events, being present in approximately 90% of first episodes of depression. The hypothalamic‐pituitary‐adrenal (HPA) axis is one of the major systems involved in responses to stress, and this system is clearly influenced by ovarian hormones. Normal women demonstrate resistance to negative feedback of both cortisol in the fast‐feedback paradigm and dexamethasone in the standard delayed‐feedback paradigm. Depressed premenopausal women show greater increases in baseline cortisol than postmenopausal depressed women and than depressed men. Studies in rodents suggest a similar resistance to glucocorticoid feedback but suggest that estradiol can function to inhibit stress responsiveness. Studies of premenopausal depressed women demonstrate lower estradiol, which suggests that there is less inhibitory feedback of estradiol on the HPA axis, while normal progesterone continues to augment stress responses further. The onset of these reproductive hormonal changes modulating stress systems at puberty may sensitize girls to stressful life events, which become more frequent at the transition to puberty and young adulthood.