bluuebunny/crossref_metadata_2025 huggingface dataset:
PATTERN FORMATION THROUGH GENETIC DRIFT AT EXPANDING POPULATION FRONTS
Authors: ALI ADNAN , GROSSKINSKY STEFAN
Published: July 2010

We investigate the nature of genetic drift acting at the leading edge of range expansions, building on recent results in [Hallatschek et al., Proc. Natl. Acad. Sci., 104(50): 19926–19930 (2007)]. A well-mixed population of two fluorescently labeled microbial species is grown in a circular geometry. As the population expands, a coarsening process driven by genetic drift gives rise to sectoring patterns with fractal boundaries, which show a non-trivial asymptotic distribution. Using simplified lattice-based Monte Carlo simulations as a generic caricature of the above experiment, we present detailed numerical results to establish a model for sector boundaries as time-changed Brownian motions. This is used to derive a general one-to-one mapping of sector statistics between circular and linear geometries, which leads to a full understanding of the sectoring patterns in terms of annihilating diffusions.
INSTABILITY OF PORTFOLIO OPTIMIZATION UNDER COHERENT RISK MEASURES
Authors: KONDOR IMRE , VARGA-HASZONITS ISTVÁN
Published: July 2010

It is shown that the axioms for coherent risk measures imply that whenever there is a pair of portfolios such that one of them dominates the other in a given sample (which happens with finite probability even for large samples), then there is no optimal portfolio under any coherent measure on that sample, and the risk measure diverges to minus infinity. This instability was first discovered in the special example of Expected Shortfall which is used here both as an illustration and as a springboard for generalization.
A FORMAL LANGUAGE THEORETIC APPROACH TO DISTRIBUTED COMPUTING ON DYNAMIC NETWORKS
Authors: ANNA LÁZÁR KATALIN
Published: July 2010

In this paper, we present a formal language theoretic approach to the behavior of complex systems of cooperating and communicating agents performing distributed computation on dynamic networks. In particular, we model peer-to-peer networks and the information harvest of Internet crawlers on the World Wide Web, employing grammar systems theoretical constructions. In grammar systems theory, the grammars can be interpreted as agents, whilst the generated language describes the behavior of the system. To characterize the various phenomena that may arise in peer-to-peer networks, we apply networks of parallel multiset string processors. The multiset string processors form teams, send and receive information through collective and individual filters. We deal with the dynamics of the string collections. To describe the information harvest of the crawlers, we employ certain regulated rewriting devices in eco-grammar systems. We illustrate the wide range of applicability of the regulated rewriting devices in the field of web crawling techniques. We demonstrate that these eco-grammar systems with rather simple component grammars suffice to identify any recursively enumerable language.
ALLOSTATIC CONTROL FOR ROBOT BEHAVIOR REGULATION: A COMPARATIVE RODENT-ROBOT STUDY
Authors: SANCHEZ-FIBLA MARTI , BERNARDET ULYSSES , WASSERMAN EREZ , PELC TATIANA , MINTZ MATTI , JACKSON JADIN C. , LANSINK CARIEN , PENNARTZ CYRIEL , VERSCHURE PAUL F. M. J.
Published: July 2010

Rodents are optimal real-world foragers that regulate internal states maintaining a dynamic stability with their surroundings. How these internal drive based behaviors are regulated remains unclear. Based on the physiological notion of allostasis, we investigate a minimal control system able to approximate their behavior. Allostasis is the process of achieving stability with the environment through change, opposed to homeostasis which achieves it through constancy. Following this principle, the so-called allostatic control system orchestrates the interaction of the homeostatic modules by changing their desired values in order to achieve stability. We use a minimal number of subsystems and estimate the model parameters from rat behavioral data in three experimental setups: free exploration, presence of reward, delivery of cues with reward predictive value. From this analysis, we show that a rat is influenced by the shape of the arena in terms of its openness. We then use the estimated model configurations to control a simulated and real robot which captures essential properties of the observed rat behavior. The allostatic reactive control model is proposed as an augmentation of the Distributed Adaptive Control architecture and provides a further contribution towards the realization of an artificial rodent.
AN AVERAGING PRINCIPLE FOR COMBINED INTERACTION GRAPHS — CONNECTIVITY AND APPLICATIONS TO GENETIC SWITCHES
Authors: KIRKILIONIS MARKUS , SBANO LUCA
Published: July 2010

Time-continuous dynamical systems defined on graphs are often used to model complex systems with many interacting components in a non-spatial context. In the reverse sense attaching meaningful dynamics to given "interaction diagrams" is a central bottleneck problem in many application areas, especially in cell biology where various such diagrams with different conventions describing molecular regulation are presently in use. In most situations these diagrams can only be interpreted by the use of both discrete and continuous variables during the modelling process, corresponding to both deterministic and stochastic hybrid dynamics. The conventions in genetics are well known, and therefore we use this field for illustration purposes. In [25] and [26] the authors showed that with the help of a multi-scale analysis stochastic systems with both continuous variables and finite state spaces can be approximated by dynamical systems whose leading order time evolution is given by a combination of ordinary differential equations (ODEs) and Markov chains. The leading order term in these dynamical systems is called average dynamics and turns out to be an adequate concept to analyze a class of simplified hybrid systems. Once the dynamics is defined the mutual interaction of both ODEs and Markov chains can be analyzed through the (reverse) introduction of the so-called Interaction Graph, a concept originally invented for time-continuous dynamical systems, see [5]. Here we transfer this graph concept to the average dynamics, which itself is introduced as a heuristic tool to construct models of reaction or contact networks. The graphical concepts introduced form the basis for any subsequent study of the qualitative properties of hybrid models in terms of connectivity and (feedback) loop formation.
The New Homelessness Revisited
Authors: Lee Barrett A. , Tyler Kimberly A. , Wright James D.
Published: July 2010

The new homelessness has drawn sustained attention from scholars over the past three decades. Definitional inconsistencies and data limitations rendered early work during this period largely speculative in nature. Thanks to conceptual, theoretical, and methodological progress, however, the research literature now provides a fuller understanding of homelessness. Contributions by sociologists and other social scientists since the mid-1990s differentiate among types of homelessness, provide credible demographic estimates, and show how being homeless affects a person's life chances and coping strategies. Agreement also exists about the main macro- and micro-level causes of homelessness. Active lines of inquiry examine public, media, and governmental responses to the problem as well as homeless people's efforts to mobilize on their own behalf. Despite the obstacles faced when studying a stigmatized population marked by high turnover and weak anchors to place, recent investigations have significantly influenced homelessness policy. A greater emphasis on prevention should further strengthen the research-policy nexus.
Organizational Approaches to Inequality: Inertia, Relative Power, and Environments
Authors: Stainback Kevin , Tomaskovic-Devey Donald , Skaggs Sheryl
Published: July 2010

This article reviews recent theoretical and empirical research addressing organizations and workplace stratification, with an emphasis on the generic organizational mechanisms responsible for producing both stability and change in workplace inequality. We propose that an organizational approach to the study of stratification should examine status- and class-based inequalities at the intersection of (a) the inertial tendencies of organizational structure, logic, and practice; (b) the relative power of actors within workplaces; and (c) organizations' institutional and competitive environments. The interplay of these generic forces either reproduces static practices and structures or leads to dynamic processes of change. We conclude with theoretical and methodological implications for analyzing social stratification through an organizational lens.
The Political Consequences of Social Movements
Authors: Amenta Edwin , Caren Neal , Chiarello Elizabeth , Su Yang
Published: July 2010

Research on the political consequences of social movements has recently accelerated. We take stock of this research with a focus on movements in democratic polities and the United States in comparative and historical perspective. Although most studies demonstrate the influence of the largest movements, this research has not addressed how much movements matter. As for the conditions under which movements matter, scholars have been revising their initial hypotheses that the strategies, organizational forms, and political contexts that aid mobilization also aid in gaining and exerting political influence. Scholars are exploring alternative arguments about the productivity of different actions and characteristics of movements and movement organizations in the varied political contexts and institutional settings they face. Researchers are also employing more innovative research designs to appraise these more complex arguments. Scholarship will advance best if scholars continue to think through the interactions between strategies, organizations, and contexts; address movement influences on processes in institutional politics beyond the agenda-setting stage; situate case studies in comparative and historical perspective; and make more comparisons across movements and issues.
World Society, Institutional Theories, and the Actor
Authors: Meyer John W.
Published: July 2010

Much modern social theory depicts society as made up of autonomous and purposive individual and organized actors. In reaction, the new institutional theories build arguments about the wider social conditions supporting stable systems of such agentic actors. Phenomenological versions, which are especially relevant to analyses of modern integrating but stateless world society, treat actor identities as themselves constructed in the wider and now global cultural context. These ideas call attention to the modern collective construction of expansive models of actors, the rapid diffusion and adoption of elaborated models of actor agency and rights, the consequently decoupled character of actor identities and activities in the modern system, and the extraordinary mobilizing potential built into the elaborated models of individual and organizational actors in world society and into the inconsistencies between these models and activity.
Socioeconomic Disparities in Health Behaviors
Authors: Pampel Fred C. , Krueger Patrick M. , Denney Justin T.
Published: July 2010

The inverse relationships between socioeconomic status (SES) and unhealthy behaviors such as tobacco use, physical inactivity, and poor nutrition have been well demonstrated empirically but encompass diverse underlying causal mechanisms. These mechanisms have special theoretical importance because disparities in health behaviors, unlike disparities in many other components of health, involve something more than the ability to use income to purchase good health. Based on a review of broad literatures in sociology, economics, and public health, we classify explanations of higher smoking, lower exercise, poorer diet, and excess weight among low-SES persons into nine broad groups that specify related but conceptually distinct mechanisms. The lack of clear support for any one explanation suggests that the literature on SES disparities in health and health behaviors can do more to design studies that better test for the importance of the varied mechanisms.
Gender and Health Inequality
Authors: Read Jen'nan Ghazal , Gorman Bridget K.
Published: July 2010

This review synthesizes gender differences in U.S. health and systematically examines the attention that gender has received in the sociological literature on health disparities over the past three decades. Its goal is to map where we have been in order to identify new directions for sociological research. We begin by summarizing major differences in U.S. men's and women's health and by reviewing explanations for observed differences. We then assess the basis for this knowledge, namely publications in major sociology journals and funding by major granting agencies, focusing on both the quantity and substantive content of this work. We couch the discussion in the broader framework of the analysis of gender in sociology and conclude with promising avenues for future work.
Conservative and Right-Wing Movements
Authors: Blee Kathleen M. , Creasap Kimberly A.
Published: July 2010

In recent years, the right has become a powerful force in many parts of the world. This review focuses primarily on the United States, with comparisons to rightist movements elsewhere. Our focus is movements, not political parties or intellectual trends. The article begins with terms and definitions and distinguishes conservative from right-wing movements. We then review changing theoretical orientations and the major findings on ideologies and characteristics of these movements. We also survey contextual factors that influence rightist mobilization and strategies used by rightist movements. We pay particular attention to New Right and New Christian Right conservative movements and to right-wing skinhead and white supremacist movements. A final section examines methodological and ethical concerns that arise in studies of the right. The conclusion recommends directions for future research.
From the Sociology of Intellectuals to the Sociology of Interventions
Authors: Eyal Gil , Buchholz Larissa
Published: July 2010

This review suggests that the sociology of intellectuals is being converted into a sociology of interventions, i.e., instead of focusing on a certain social type, it analyzes the movement by which knowledge and expertise are mobilized to inform a value-laden intervention in the public sphere. We first demonstrate that the classical sociology of intellectuals was centered on a problematic of allegiance that no longer seems productive. In addition, we show that by focusing on a particular social type it remained limited to only one mode of intervention into the public sphere. We then review two literatures that distance themselves from the classical problematic and that could be integrated under the common rubric of a sociology of interventions: The first literature analyzes intellectual fields and markets. It moves away from the sociology of intellectuals by multiplying the relevant actors and depersonalizing the term “intellectual” so that it no longer stands for a social type but for the capacity to make a public intervention, a capacity to which many different actors lay claim. The second literature analyzes the public deployment of expertise. It multiplies not simply the actors laying claim to the mantle of the intellectual, but the formats and modes of intervention itself, i.e., the different ways in which knowledge and expertise can be inserted into the public sphere.
Causal Mechanisms in the Social Sciences
Authors: Hedström Peter , Ylikoski Petri
Published: July 2010

During the past decade, social mechanisms and mechanism-based explanations have received considerable attention in the social sciences as well as in the philosophy of science. This article critically reviews the most important philosophical and social science contributions to the mechanism approach. The first part discusses the idea of mechanism-based explanation from the point of view of philosophy of science and relates it to causation and to the covering-law account of explanation. The second part focuses on how the idea of mechanisms has been used in the social sciences. The final part discusses recent developments in analytical sociology, covering the nature of sociological explananda, the role of theory of action in mechanism-based explanations, Merton's idea of middle-range theory, and the role of agent-based simulations in the development of mechanism-based explanations.
Comparative Analyses of Public Attitudes Toward Immigrants and Immigration Using Multinational Survey Data: A Review of Theories and Research
Authors: Ceobanu Alin M. , Escandell Xavier
Published: July 2010

This article critically reviews the intersectional locus of public opinion scholarship and immigration studies that make use of data from multinational survey projects. Specifically, it emphasizes current cross-national research seeking to understand the causes, manifestations, and implications of attitudes toward immigrants and immigration in economically advanced countries of the world. Despite rapid expansion, the field suffers from several methodological challenges and theoretical constraints. A succinct exposure of trends and patterns is followed by presentations of influential theoretical perspectives and established individual- and contextual-level determinants. The review suggests that strengthening the conceptual apparatus and enlarging the analytical focus are priorities. It concludes with some observations on how to circumvent these problems and to bridge current research with future explorations of the embedded nature of such public attitudes.
Causal Inference in Sociological Research
Authors: Gangl Markus
Published: July 2010

Originating in econometrics and statistics, the counterfactual model provides a natural framework for clarifying the requirements for valid causal inference in the social sciences. This article presents the basic potential outcomes model and discusses the main approaches to identification in social science research. It then addresses approaches to the statistical estimation of treatment effects either under unconfoundedness or in the presence of unmeasured heterogeneity. As an update to Winship & Morgan's (1999) earlier review, the article summarizes the more recent literature that is characterized by a broader range of estimands of interest, a renewed interest in exploiting experimental and quasi-experimental designs, and important progress in the areas of semi- and nonparametric estimation of treatment effects, difference-in-differences estimation, and instrumental variable estimation. The review concludes by highlighting implications of the recent econometric and statistical literature for sociological research practice.
MicroRNA-146: Tiny Player in Neonatal Innate Immunity?
Authors: Lederhuber Hans , Baer Katharina , Altiok Ipek , Sadeghi Kambis , Herkner Kurt R. , Kasper David C.
Published: July 2010

Background: Concise regulation of the Toll signaling pathway is mandatory in neonatal innate immunity. The microRNA-146 family (miR-146a/b) was recently reported to be a regulator of Toll-like receptor 4 (TLR4) through a negative feedback loop mechanism. Acting as a potent regulator, miRNA helps to protect the organism from developing overwhelming proinflammatory immune responses leading to septic shock or chronic inflammatory diseases. Objective: We investigated for the first time whether miRNA-146a/b plays a regulatory role in human monocytes derived from infant cord or adult blood, and whether differences in miRNA-146 expression exist. Methods: Expression profiles of miR-146a/b and TLR4 were studied by real-time PCR upon stimulation with lipopolysaccharide. Results: Both members of the miRNA-146 family showed a time-dependent upregulation. For miR-146a, a statistically higher significant increase was found after 24 h of stimulation in monocytes from cord blood compared to those derived from adults. In contrast, no differences were found for miR-146b and TLR4, respectively. Conclusion: We conclude that differences between the negative regulatory role for miR-146a obviously exist in neonatal and adult TLR4 signaling, and suggest that more intense research in the involvement of miRNA in immune regulation will facilitate the understanding of the development and function of the innate immune system of neonates.
Clinical Criteria for the Diagnosis of Parkinson’s Disease
Authors: Reichmann Heinz
Published: July 2010

The diagnosis of Parkinson’s disease (PD) follows the UK Brain Bank Criteria, which demands bradykinesia and one additional symptom, i.e. rigidity, resting tremor or postural instability. The latter is not a useful sign for the early diagnosis of PD, because it does not appear before Hoehn and Yahr stage 3. Early symptoms of PD which precede the onset of motor symptoms are hyposmia, REM sleep behavioral disorder, constipation, and depression. In addition, an increasing number of patients whose PD is related to a genetic defect are being described. Thus, genetic testing may eventually develop into a tool to identify at-risk patients. The clinical diagnosis of PD can be supported by levodopa or apomorphine tests. Imaging studies such as cranial CT or MRI are helpful to distinguish idiopathic PD from atypical or secondary PD. SPECT and PET methods are valuable to distinguish PD tremor from essential tremor if this is clinically not possible. Using all of these methods, we may soon be able to make a premotor diagnosis of PD, which will raise the question whether early treatment is possible and ethically and clinically advisable.
Place Value of Transcranial Sonography in Early Diagnosis of Parkinson’s Disease
Authors: Berg Daniela , Gaenslen Alexandra
Published: July 2010

Transcranial B-mode sonography (TCS) is a relatively new method which has been proven to be helpful in the diagnosis of Parkinson’s disease (PD). Due to the underlying physical principles, supplementary information to other neuroimaging methods can be derived. Substantia nigra (SN) hyperechogenicity is the characteristic feature of idiopathic PD, which can help in the differentiation of atypical parkinsonian syndromes like multiple system atrophy or progressive supranuclear palsy. Besides, the quick ‘look into the brain’ can easily visualize an enlargement of the ventricular system, alterations of the basal ganglia like increased contents of calcium or trace metals, or a missing brain stem raphe, typically seen in depressive disorders, and can therefore give further diagnostic hints for symptomatic parkinsonian syndromes. Many studies indicate that SN hyperechogenicity constitutes a stable marker, irrespective of the disease stage. In a prospective study of patients with very first signs of yet unclear parkinsonism, a high predictive value of TCS for the diagnosis of PD could be proven. Moreover, there is accumulating evidence that SN hyperechogenicity could play a role in the premotor diagnosis of PD. In this review, the additional diagnostic value of TCS in the early diagnosis of PD as well as limitations of the method are being discussed.
Positron Emission Tomography in Diagnosis and Differential Diagnosis of Parkinson’s Disease
Authors: Tatsch Klaus
Published: July 2010

Parkinson’s disease (PD) and atypical Parkinsonian syndromes (aPS) belong to the most common neurologic illnesses. Diagnosis and differential diagnosis of these syndromes is primarily based on well-defined clinical criteria, however, may be difficult in early and particular preclinical/premotor stages. Molecular imaging with PET offers here a broad variety of tools supporting the classification of Parkinsonian syndromes including their early and differential diagnosis, assessment of disease progression and evaluation of the efficacy of therapies. The more widely applied PET imaging techniques have focused on the assessment of neurotransmitter systems, here predominantly the pre- and postsynaptic dopaminergic functions, but also others like the serotonergic and cholinergic system. Beyond, refined methods depict distinct patterns of glucose metabolism in the various Parkinsonian syndromes, and focus on further targets such as neuroinflammation, load of amyloid plaques, and cardiac sympathetic denervation. This overview discusses the important PET applications in the field with a main emphasis on their clinical utilization but also highlights scientific applications which may grant further insights in the pathophysiology of PD and aPS.
Is the JAK2 V617F Mutation a Hallmark for Different Forms of Thrombosis?
Authors: Zerjavic Katja , Zagradisnik Boris , Stangler Herodez Spela , Lokar Lidija , Glaser Krasevac Marjana , Kokalj Vokac Nadja
Published: July 2010

Background/Aims: The association between venous thrombosis outside the splanchnic area as well arterial thromboembolism and the JAK2 V617F mutation, an important marker for chronic myeloproliferative neoplasms (MPN), is not completely clear. Methods: Four hundred forty-four patients with venous thrombosis of the lower/upper limbs and/or pulmonary embolism and 60 patients with ischemic stroke were screened for the JAK2 V617F mutation, factor V Leiden, and factor II G20210A. Results: The JAK2 V617F mutation was detected in 1.4% of patients with venous thrombosis and in 3.3% of patients with ischemic stroke. Because 6 out of 2,430 control individuals with no medical history of venous thrombosis, stroke, or MPN were positive for the JAK2 V617F mutation, a significant association was observed (OR 5.53, CI 1.77–17.2, p = 0.0053 for venous thrombosis; OR 13.9, CI 2.75–70.5, p = 0.0145 for stroke). Conclusion: We provide evidence of the association between the JAK2 V617F mutation and different forms of thrombosis. This association is comparable with the association between inherited risk factors (factor V Leiden and factor II G20210A) and thrombotic events, but with a much lower prevalence of the mutation. Finally, the JAK2 V617F mutation is not absent from the general population despite being considered somatic and an acquired genetic variation.
A Rare Case of Chronic Lymphocytic Leukemia with Hypercalcemia Induced by Elevated Parathyroid Hormone-Related Peptides
Authors: Kampfenkel T. , Baraniskin A. , Teschendorf C. , Schmiegel W. , Massenkeil G.
Published: July 2010

Hypercalcemia in malignancies is a frequent complication, mostly affecting patients with solid tumors or multiple myeloma. Calcium elevation is induced by direct bone infiltration of a tumor mass or through calcium liberation from the skeleton by a humoral mediator. The latter mechanism is referred to as humoral hypercalcemia of malignancy (HHM). Frequent mediators of HHM are parathyroid hormone-related peptides (PTHrP). We report a patient with chronic lymphocytic leukemia and hypercalcemia induced by PTHrP. In contrast to solid tumors and myeloma, PTHrP-induced HHM is very rare in low-grad lymphoma including chronic lymphocytic leukemia. Therapeutical approaches consist of cytoreductive treatment and calcium-lowering therapy with bisphosphonates.
A Meta-Analysis of Placebo-Controlled Clinical Trials Assessing the Efficacy and Safety of Incretin-Based Medications in Patients with Type 2 Diabetes
Authors: Fakhoury Walid K.H. , LeReun Corinne , Wright Donna
Published: July 2010

Aims: A systematic review of the literature, in combination with a meta-analysis of randomized controlled trials comparing treatments with placebo, was conducted to provide an update on the clinical efficacy and safety of incretin-based medications in adult patients with type 2 diabetes. Methods: A literature search (2000–2009) identified 38 placebo-controlled trials (phase II or later – parallel design) comparing exenatide (n = 8), liraglutide (n = 7), vildagliptin (n = 11) and sitagliptin (n = 12) with placebo. Outcomes were change from baseline in HbA1c and in weight, and the number of patient-reported hypoglycemic episodes. HbA1c and weight outcomes were analyzed as weighted mean differences (WMD), and the number of hypoglycemic episodes as relative risks (RR). Results: Patients receiving liraglutide showed greater reduction in HbA1c in comparison to placebo (WMD = –1.03, 95% confidence interval, CI = –1.16 to –0.90, p < 0.001) than those on sitagliptin (WMD = –0.79, 95% CI = –0.93 to –0.65, p < 0.001), exenatide (WMD = –0.75, 95% CI = –0.83 to –0.67, p < 0.001) or vildagliptin (WMD = –0.67, 95% CI = –0.83 to –0.52, p < 0.001). Weight was statistically significantly negatively associated with exenatide (WMD = –1.10, 95% CI = –1.32 to –0.87, p < 0.001) and positively associated with sitagliptin (WMD = 0.60, 95% CI = 0.33–0.87, p < 0.001) and vildagliptin (WMD = 0.56, 95% CI = 0.27–0.84, p < 0.001). The number of patient-reported hypoglycemic episodes was statistically significantly associated with the use of sitagliptin (RR = 2.56, 95% CI = 1.23–5.33, p = 0.01) and exenatide (RR = 2.40, 95% CI = 1.30–4.11, p = 0.002). Conclusion: Incretin-based therapies are effective in glycemic control and also offer other advantages such as weight loss (exenatide and liraglutide). This may have an important impact on patient adherence to medication.
MRI Findings May Predict Early Neurologic Deterioration in Acute Minor Stroke or Transient Ischemic Attack due to Intracranial Atherosclerosis
Authors: Kim Joon-Tae , Kim Hye-Jin , Yoo Sung-Hee , Park Man-Seok , Kwon Sun U. , Cho Ki-Hyun , Kim Jong S. , Kang Dong-Wha
Published: July 2010

Background: Patients with intracranial atherosclerosis (ICAS) are at high risk of early recurrence or neurologic deterioration. Although minor stroke and transient ischemic attack (TIA) seem benign, their occurrence in patients with ICAS may lead to early neurological deterioration (END). We aimed to identify factors associated with END in ICAS patients presenting with acute minor stroke or TIA, with a focus on early MRI findings. Methods: This was a retrospective analysis of consecutive patients with acute minor stroke or TIA admitted within 12 h of symptom onset. Patients with moderate-severe stenosis of the middle cerebral artery or basilar artery (BA) were included. All patients underwent MRI, including diffusion-weighted imaging (DWI), and magnetic resonance angiography. DWI lesion patterns were classified as perforating artery infarcts, pial infarcts, territorial infarcts and border zone infarcts (BIs). END was diagnosed as an increase of ≧4 points on the National Institutes of Health Stroke Scale from baseline during the 1st week. Results: Of the 95 patients enrolled in the study, 14 (14.7%) developed END. Independent predictors of END were the presence of BIs on baseline DWI (odds ratio, OR, 7.21; 95% confidential interval, CI, 1.88–27.66; p = 0.004) and BA disease (OR, 4.33; 95% CI, 1.11–16.92; p = 0.035). Conclusions: ICAS patients with BI and BA disease are at high risk of END after minor stroke or TIA. Early radiological findings may be helpful in predicting END and guiding early treatment strategies.
Optimisation of Cosolvent Concentration for Topical Drug Delivery III – Influence of Lipophilic Vehicles on Ibuprofen Permeation
Authors: Watkinson R.M. , Guy R.H. , Oliveira G. , Hadgraft J. , Lane M.E.
Published: July 2010

Previously, we have reported the effects of water, ethanol, propylene glycol and various binary and ternary mixtures of these solvents on the permeation of ibuprofen in model membranes and in skin. The present study investigates the influence of lipophilic vehicles on the transport of ibuprofen in silicone membrane and in human skin. The permeation of ibuprofen was measured from mineral oil (MO), Miglyol® 812 (MG) and binary mixtures of MO and MG. The solubility of ibuprofen was 5-fold higher in MG than in MO, however, the permeation of ibuprofen from the pure vehicles and combinations of both was comparable in silicone membrane. Additionally, there were no significant differences in skin permeation for MO and MG vehicles. When the permeation of various hydrophilic and lipophilic vehicles is considered, a trend between flux values for the model membrane and skin is evident (r2 = 0.71). The findings suggest that silicone membrane may provide information on qualitative trends in skin permeation for vehicles of diverse solubility and partition characteristics.
The ‘Strip Method’: A Simple Method for Plaque pH Assessment
Authors: Carlén A. , Hassan H. , Lingström P.
Published: July 2010

Aim: The aim of the study was to evaluate if pH indicator strips could be used for measurements of plaque pH acidogenicity in situ. Method: Interproximal plaque pH was measured before and up to 60 min after a 10% sucrose rinse in 30 healthy volunteers using pH indicator strips and the microtouch method in parallel. Results: It was found that the ‘strip method’ could determine changes in plaque pH to the same extent as the microtouch method (correlation coefficient 0.99). Conclusion: Since the ‘strip method’ is inexpensive and easy to handle, it may be applicable for assessment of plaque acidogenicity in the clinic.
Efficacy and Effectiveness of Antidepressants: Current Status of Research
Authors: Pigott H. Edmund , Leventhal Allan M. , Alter Gregory S. , Boren John J.
Published: July 2010

Background: This paper examines the current status of research on the efficacy and effectiveness of antidepressants. Methods: This paper reviews four meta-analyses of efficacy trials submitted to America’s Food and Drug Administration (FDA) and analyzes STAR*D (Sequenced Treatment Alternatives to Relieve Depression), the largest antidepressant effectiveness trial ever conducted. Results: Meta-analyses of FDA trials suggest that antidepressants are only marginally efficacious compared to placebos and document profound publication bias that inflates their apparent efficacy. These meta-analyses also document a second form of bias in which researchers fail to report the negative results for the pre-specified primary outcome measure submitted to the FDA, while highlighting in published studies positive results from a secondary or even a new measure as though it was their primary measure of interest. The STAR*D analysis found that the effectiveness of antidepressant therapies was probably even lower than the modest one reported by the study authors with an apparent progressively increasing dropout rate across each study phase. Conclusions: The reviewed findings argue for a reappraisal of the current recommended standard of care of depression.
No Effect of Adding Brief Dynamic Therapy to Pharmacotherapy in the Treatment of Obsessive-Compulsive Disorder with Concurrent Major Depression
Authors: Maina Giuseppe , Rosso Gianluca , Rigardetto Sylvia , Chiadò Piat Simone , Bogetto Filippo
Published: July 2010

Background: Until now no studies have investigated the benefits of adding brief dynamic therapy (BDT) to medication in obsessive-compulsive disorder (OCD), while a number of recent investigations have demonstrated the efficacy of supplemental BDT among patients with major depressive disorders (MDD). The objective of the present study was to explore the efficacy of BDT combined with pharmacotherapy in comparison with pharmacotherapy alone in the treatment of OCD with concurrent MDD. Methods: A 12-month randomized clinical trial compared a standard selective serotonin reuptake inhibitor treatment with (n = 27) or without (n = 30) supplemental BDT in patients with OCD and concurrent MDD. Supplemental BDT was added during the first 16-week trial; all patients continued to be treated with only pharmacotherapy in the following continuation phase. The primary efficacy assessments were the Yale-Brown Obsessive Compulsive Scale and the 17-item Hamilton Rating Scale for Depression; the secondary efficacy measures included the Clinical Global Impression scale and the Global Assessment of Functioning. The data analysis was conducted on the ‘intent-to-treat (ITT) efficacy patient sample’. Results: Fifty patients completed the study. No difference between the 2 treatment groups was found at any point by any assessment method in the ITT study sample. Conclusions: Supplemental BDT in the treatment of patients with OCD with concurrent MDD who are receiving effective medication has no significant clinical effect on both obsessive and depressive symptoms.
Long-Term Follow-Up of the First Patients to Undergo Transcatheter Alcohol Septal Ablation
Authors: Lyne J.C. , Kilpatrick T. , Duncan A. , Knight C.J. , Sigwart U. , Fox K.M.
Published: July 2010

We describe the 10-year outcome of the first-in-human series of 12 patients with hypertrophic cardiomyopathy treated with alcohol septal ablation. There was no 30-day mortality. Survival free of death, internal cardiac defibrillator discharge for treatment of ventricular fibrillation or tachycardia, severe New York Heart Association (NYHA) class III/IV and/or Canadian Cardiovascular Society class III/IV symptoms and the need for surgical myectomy in this cohort was 91% at 1 year and 73% at 10 years. The reduction in outflow tract gradient was maintained over the 10 years, from a mean preoperative gradient of 70 mm Hg to a median of 3 mm Hg at 126 months of follow-up (p < 0.01). Two patients (16%) underwent a further ablation procedure. Two patients (16%) suffered sudden cardiac death, 91 and 102 months after the procedure. Long-term symptom benefit was experienced by all patients, with a reduction in mean NYHA class from 2.7 ± 0.6 before the procedure to 1 after the procedure at the last follow-up (p < 0.01). This historic small cohort study demonstrates that septal ablation can provide long-term haemodynamic and symptomatic benefit.
Disinfection of Bovine Enamel by Microwave Irradiation: Effect on the Surface Microhardness and Demineralization/Remineralization Processes
Authors: Viana P.S. , Machado A.L. , Giampaolo E.T. , Pavarina A.C. , Vergani C.E.
Published: July 2010

Enamel specimens need to be disinfected before being used in intraoral appliances and the disinfection method must not affect the integrity of the tooth. This study evaluated the effectiveness of microwave bovine enamel disinfection and its effect on the surface microhardness (SMH) and cross-sectional microhardness (CSMH) of sound, demineralized and remineralized enamel. Forty enamel specimens were divided into two groups (n = 20): control (nonirradiated) and microwave. Microwave specimens were immersed in water and irradiated (650 W/3 min). Specimens were incubated at 37°C for 7 days under aerobic and anaerobic conditions. An aliquot was removed for counting, plated at serial dilutions on blood agar plates, which were incubated aerobically and anaerobically. The colony-forming units were calculated. Other 20 enamel specimens (4 × 4 mm) were embedded in acrylic resin, polished and sliced into two halves: one of the fragments was reserved as control while the other was microwaved. SMH and CSMH of sound enamel were analyzed for both groups. The CSMH was further evaluated after demineralization and remineralization cycles. The Knoop integral (ΔKI) was also calculated. Data were analyzed statistically by paired Student’s t test (α = 0.05). While control specimens showed microbial growth, those microwaved were disinfected. There were no significant differences in SMH, CSMH and ΔKI between the control and microwave groups. Microwave irradiation for 3 min at 650 W was effective for the complete disinfection of bovine enamel specimens without affecting the SMH and CSMH of sound, demineralized and remineralized enamel.
Is the Use of β-Blockers in COPD Still an Unresolved Dilemma?
Authors: Foresi Antonio , Cavigioli Giampaolo , Signorelli Giordano , Pozzoni Maria Beatrice , Olivieri Dario
Published: July 2010

β-Blockers are competitive antagonists at β-adrenergic receptors (β-AR) and are a life-saving form of treatment in different cardiovascular diseases (CVD). Despite current guidelines supporting the use of selective β1-blockers in patients with CVD and especially in heart failure (HF), they are still largely underused, mostly as a consequence of the presence of chronic obstructive pulmonary disease (COPD). In primary care, prevalence of COPD in patients with HF is approximately 25%, and it will rise in the next years. In the general population, only 20% of COPD patients with HF are treated with β-blockers. β-Blockers may result in pulmonary adverse effects that are relevant to COPD patients. Bronchoconstriction may be the consequence of: absence of cardioselectivity; loss of cardioselectivity at high doses, and unopposed stimulation of cholinergic muscarinic M2 receptors. The concern of inducing bronchospasm is the more likely explanation of a poor prescription of β-blockers in patients with CVD also suffering from COPD. However, under carefully controlled conditions, which include close monitoring of lung function and appropriate selection of the drug and titration of the dose on a case-by-case basis, selective β1-blockers can be safely administered to most patients with COPD. Pneumologists and cardiologists should develop a detailed and standardized protocol to guide the use of selective β1-blockers in everyday practice, which could significantly reduce the physicians’ mistrust of β-blockers in COPD patients.
Comparative Effectiveness of Low- and High-Fidelity Bronchoscopy Simulation for Training in Conventional Transbronchial Needle Aspiration and User Preferences
Authors: Davoudi Mohsen , Wahidi Momen M. , Zamanian Rohani Nazanin , Colt Henri G.
Published: July 2010

Background: Conventional transbronchial needle aspiration (TBNA) can be learned using high-fidelity virtual-reality platforms and low-fidelity models comprised of molded silicone or excised animal airways. Objectives: The purpose of this study was to determine perceptions and preferences of learners and instructors regarding the comparative effectiveness of low-fidelity and high-fidelity bronchoscopy simulation for training in TBNA. Methods: During the 2008 annual CHEST conference, a prospective randomized crossover design was used to train study participants in three methods of conventional TBNA using low- and high-fidelity models. Likert style questions were administered to learners and instructors in order to elicit preferences and opinions regarding educational effectiveness of the models. Results were tabulated and depicted in graphic format, with medians calculated. Results: Learners felt that the models were equally enjoyable (13–13) and enthusiasm generating (low 17-high 15). There was preference for low-fidelity in terms of realism (23–17), ease of learning (20–6), and learning all three TBNA methods (31–7 for hub-against-wall, 31–6 for jabbing, 29–6 for piggyback). Low-fidelity was preferred as an ideal model overall (19–11). Instructors thought that low-fidelity was more useful in teaching TBNA (9–0 for all three methods). Instructors perceived the low-fidelity model overall as an ideal tool for learning TBNA (8–0) and a more effective teaching instrument (8–0). Conclusion: Based on learner and instructor perceptions, a low-fidelity model is superior to a high-fidelity platform for training in three methods of conventional TBNA.
Predictive Value of Cancer Stem-Like Cells and Cancer-Associated Genetic Markers for Peritoneal Recurrence of Colorectal Cancer in Patients after Curative Surgery
Authors: Nakamura Keisuke , Iinuma Hisae , Aoyagi Yoshiko , Shibuya Hajime , Watanabe Toshiaki
Published: July 2010

Objective: The new concept of cancer stem cells has implications in terms of possible application for novel diagnostic and therapeutic procedures. Recently, the CD133 molecule was reported as a marker of cancer stem-like cells in colorectal cancer (CRC). In this study, we examined the prognostic value of free cancer cells in peritoneal washings from CRC patients after curative resection using multiple molecular markers, including cancer stem-like cells. Methods: A total of 170 CRC patients who had undergone curative surgery were studied. Peritoneal washings of the Douglas cavity were collected and used for cytology and molecular diagnosis. Real-time RT-PCR for carcinoembryonic antigen (CEA), cytokeratin 20 (CK20) and CD133 mRNA was performed to detect free cancer cells. Results: Molecular detection of CEA, CK20 and/or CD133 (CEA/CK20/CD133) mRNA of the peritoneal washings showed a significant correlation with lymph node metastasis and the tumor stage. The overall survival (OS) rates and peritoneal recurrence-free survival (PFS) rates in CEA/CK20/CD133 mRNA-positive patients were significantly lower than those of marker gene-negative patients. CD133/CEA/CK20 mRNAs in peritoneal washings were independent prognostic factors for OS and PFS. Conclusion: Molecular detection of free cancer cells using multimarkers, including cancer stem-like cells in peritoneal washings of post-curative surgery CRC patients, are useful in prognosis prediction.
Coffee, Decaffeinated Coffee, Caffeine, and Tea Consumption in Young Adulthood and Atherosclerosis Later in Life
Authors: Reis Jared P. , Loria Catherine M. , Steffen Lyn M. , Zhou Xia , van Horn Linda , Siscovick David S. , Jacobs David R. , Carr J. Jeffrey
Published: July 2010

Objective—

To determine the association of coffee, decaffeinated coffee, caffeine, and tea consumption in young adulthood with the presence and progression of coronary artery calcified (CAC) plaque and carotid intima-media thickness later in life.

Methods and Results—

The Coronary Artery Risk Development in Young Adults (CARDIA) Study is a cohort of 5115 white and black adults who were aged 18 to 30 years when they completed a baseline clinic examination from 1985 to 1986. Subsequent examinations were conducted 2, 5, 7, 10, 15, and 20 years later. After multivariable adjustment, no association was observed between average coffee, decaffeinated coffee, or caffeine consumption (years 0 and 7) and presence of CAC (score, >0 Agatston units at year 15 or 20), CAC progression (incident CAC at year 20 or increase in CAC score by ≥20 Agatston units), or high carotid intima-media thickness (>80th percentile, year 20). However, tea consumption displayed a nonsignificant trend for an inverse association with CAC (
P
=0.08 for trend) and an inverse association with CAC progression (
P
=0.04 for trend) but no association with high carotid intima-media thickness (
P
>0.20 for trend). Stratification of the coffee analyses by sex, race, or smoking yielded similar nonsignificant patterns.

Conclusion—

We observed no substantial association between coffee or caffeine intake and coronary and carotid atherosclerosis. However, our results suggested an inverse association between tea and CAC but not carotid atherosclerosis.