bluuebunny/crossref_metadata_2025 huggingface dataset:
Ammonia increases paracellular permeability of rat brain endothelial cells by a mechanism encompassing oxidative/nitrosative stress and activation of matrix metalloproteinases
Authors: Skowrońska Marta , Zielińska Magdalena , Wójcik‐Stanaszek Luiza , Ruszkiewicz Joanna , Milatovic Dejan , Aschner Michael , Albrecht Jan
Published: January 2012

J. Neurochem. (2012) 121, 125–134.

Ammonia is responsible for cerebral edema associated with acute liver failure, but the role of the vasogenic mechanism has been a matter of dispute. Here, we tested the hypothesis that ammonia induces changes in blood–brain barrier (BBB) permeability by a mechanism coupled to oxidative/nitrosative stress (ONS) evoked in the BBB‐forming cerebral capillary endothelial cells. Treatment of a rat brain endothelial cell line with ammonia (5 mmol/L, 24 h) caused accumulation of ONS markers: reactive oxygen species, nitric oxide and peroxidation products of phospholipid‐bound arachidonic acid, F2‐isoprostanes. Concurrently, ammonia increased the activity of extracellular matrix metalloproteinases (MMP‐2/MMP‐9), increased cell permeability to fluorescein isothiocyanate‐dextran (40 kDa), and increased the expression of y+LAT2, a transporter that mediates the uptake to the cells of the nitric oxide precursor, arginine. The increase of cell permeability was ameliorated upon co‐treatment with a MMP inhibitor, SB‐3CT and with an antioxidant, glutathione diethyl ester, which also reduced F2‐isoprostanes. Ammonia‐induced ONS was attenuated by cytoprotective agents l‐ornithine, phenylbutyrate, and their conjugate l‐ornithine phenylbutyrate, an ammonia‐trapping drug used to treat hyperammonemia. The results support the concept that ONS and ONS‐related activation of MMPs in cerebral capillary endothelial cells contribute to the alterations in BBB permeability and to the vasogenic component of cerebral edema associated with acute liver failure.
Equity Risk Incentives and Corporate Tax Aggressiveness
Authors: REGO SONJA OLHOFT , WILSON RYAN
Published: January 2012

This study examines equity risk incentives as one determinant of corporate tax aggressiveness. Prior research finds that equity risk incentives motivate managers to make risky investment and financing decisions, since risky activities increase stock return volatility and the value of stock option portfolios. Aggressive tax strategies involve significant uncertainty and can impose costs on both firms and managers. As a result, managers must be incentivized to engage in risky tax avoidance that is expected to generate net benefits for the firm and its shareholders. We predict that equity risk incentives motivate managers to undertake risky tax strategies. Consistent with this prediction, we find that larger equity risk incentives are associated with greater tax risk and the magnitude of this effect is economically significant. Our results are robust across four measures of tax risk, but do not vary across several proxies for strength of corporate governance. We conclude that equity risk incentives are a significant determinant of corporate tax aggressiveness.
Option Prices Leading Equity Prices: Do Option Traders Have an Information Advantage?
Authors: JIN WEN , LIVNAT JOSHUA , ZHANG YUAN
Published: January 2012

Recent evidence shows that option volatility skews and volatility spreads between call and put options predict equity returns. This study investigates whether such predictive ability is driven by option traders’ information advantage. We examine the predictive ability of volatility skews and volatility spreads around significant information events including earnings announcements, other firm‐specific information events, and events that trigger significant market reactions. Consistent with option traders having an information advantage relative to equity traders before information events, we find that the option measures immediately before these events have higher predictive ability for short‐term event returns than they do in a more dated window or before a randomly selected pseudo‐event. We also find that option measures have predictive ability after information events. However, this predictive ability holds only for unscheduled corporate announcements, which suggests that, relative to equity traders, option traders have superior ability to process less anticipated information.
Natural triterpenes modulate immune‐inflammatory markers of experimental autoimmune encephalomyelitis: therapeutic implications for multiple sclerosis
Authors: Martín R , Hernández M , Córdova C , Nieto ML
Published: January 2012

BACKGROUND AND PURPOSE

Multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE), are inflammatory demyelinating diseases that develop as a result of deregulated immune responses causing glial activation and destruction of CNS tissues. Oleanolic acid and erythrodiol are natural triterpenes that display strong anti‐inflammatory and immunomodulatory activities. Oleanolic acid beneficially influences the course of established EAE. We now extend our previous observations to erythrodiol and address the efficacy of both compounds to protect against EAE, given under different regimens.

EXPERIMENTAL APPROACH

The utility of both triterpenes in disease prevention was evaluated at a clinical and molecular level: in vivo through their prophylactic administration to myelin oligodendrocyte protein‐immunized C57BL/6 mice, and in vitro through their addition to stimulated‐BV2 microglial cells.

KEY RESULTS

These triterpenes protected against EAE by restricting infiltration of inflammatory cells into the CNS and by preventing blood–brain barrier disruption. Triterpene‐pretreated EAE‐mice exhibited less leptin secretion, and switched cytokine production towards a Th2/regulatory profile, with lower levels of Th1 and Th17 cytokines and higher expression of Th2 cytokines in both serum and spinal cord. Triterpenes also affected the humoral response causing auto‐antibody production inhibition. In vitro, triterpenes inhibited ERK and rS6 phosphorylation and reduced the proliferative response, phagocytic properties and synthesis of proinflammatory mediators induced by the addition of inflammatory stimuli to microglia.

CONCLUSIONS AND IMPLICATIONS

Both triterpenes restricted the development of the characteristic features of EAE. We envision these natural products as novel helpful tools for intervention in autoimmune and neurodegenerative diseases including MS.
Upper normal threshold of serum alanine aminotransferase in identifying individuals at risk for chronic liver disease
Authors: Park Ha Na , Sinn Dong Hyun , Gwak Geum‐Youn , Kim Jee Eun , Rhee Sang Youl , Eo Sung June , Kim Yu Jin , Choi Moon Seok , Lee Joon Hyeok , Koh Kwang Cheol , Paik Seung Woon , Yoo Byung Chul
Published: January 2012

Background/Aims

Serum alanine aminotransferase (ALT) is an easily available, low‐cost screening tool for detecting silent chronic liver disease. Recent studies have suggested that the currently accepted healthy ALT thresholds be lowered.

Methods

In this retrospective cross‐sectional study, we determined upper thresholds for ALT values in a nationally representative healthy cohort (n = 3337) from the Fourth Korea National Health and Nutrition Examination Survey (KNHANES IV). Sensitivity and specificity of the currently used ALT threshold (40 IU/L, regardless of gender) was compared against study‐derived, gender‐specific ALT thresholds for detecting individuals at risk for chronic liver disease in 27 913 health check‐up participants.

Results

The 95th percentile levels for ALT in healthy weight, metabolically normal, liver disease‐free KNHANES participants were 34 IU/L for men and 25 IU/L for women. The prevalence of ALT elevation among health check‐up participants was 11.0% in currently used thresholds, and increased to 22.6% with study‐derived, gender‐specific thresholds. Of the population who were additionally defined to have elevated ALT levels under new ALT threshold, 65.7% were at risk for chronic liver disease. Sensitivity for detecting individuals at risk for chronic liver disease improved from 18 to 33% with new thresholds whereas a trade‐off in specificity (from 96 to 88%) was observed.

Conclusions

It is recommendable to lower the current ALT thresholds to better identify individuals at risk for chronic liver disease.
Democratic Politics between the Market and the Forum
Authors: Saunders Ben
Published: January 2012

Economic analyses of democracy often draw an analogy between democratic procedures and the ‘consumer sovereignty’ of the marketplace. In contrast, normative ideals of democracy often propose that voters should aim at the common good or justice. It is suggested that there is a fundamental difference between the appropriate norms of the market, in which self-interest is permitted, and those of the political forum, in which self-interest is prohibited. These ideals are apt, however, to invite charges of utopianism. While I accept that morality may sometimes be demanding, my aim in this article is to argue that the appropriate norms of the democratic forum are not as demanding as sometimes suggested; the market/forum contrast is often exaggerated. The market is not a state of nature, so some moral constraints apply even there. More importantly, self-interest is allowed some place in the political arena, at least where justice or the common good is indeterminate. There is no need for agents to set aside their private interests entirely in the political arena. Thus, the ultimate guiding principles of the market and the forum are the same: agents are free to promote their self-interest within the constraints established by justice or the rights of other agents. It may be that these constraints are more restrictive in politics than in the marketplace, but the difference between the two arenas is one of degree rather than kind. Unless we think that even constrained pursuit of self-interest is too demanding, we have no reason to regard these norms as utopian.
Tackling the Financial Crisis
Authors: Keaney Michael
Published: January 2012

Following the onset of the global financial crisis in 2007, there has been an abundance of books and articles purporting to explain its causes and consequences, with some offering tentative remedies. One of the major targets of criticism was the economics profession, which ignored the warnings of impending catastrophe prior to the onset of the crisis. As a result its public esteem suffered, much like that of the bankers and other professional groups implicated in the crisis. The books under review in this article represent a broad cross-section of work undertaken within the disciplinary boundaries of political science. As such, they provide complementary insights that yield deeper understanding of both the origins of the crisis and the nature of the solutions required to prevent a recurrence.
Politics and the Market in Twenty-First-Century China: Strategies of Authoritarian Management of State–Society Relations
Authors: Lin Kun-Chin
Published: January 2012

The four volumes reviewed in this article examine the common theme of the sustainability of China's authoritarian regime as it faces tremendous centripetal forces of market expansion, increased administrative complexity, and social differentiation brought about by the post-Mao Zedong reforms. I argue that the shared focus of several authors on the Chinese Communist party's exercise of individual-level controls – either through internal disciplinary and reward mechanisms or through the strategic co-optation of private interests and civil society groups – provides valuable insights into the organisational basis of authority and exchange emanating from the party-state. At the same time, this perspective manifests inherent biases in accurately assessing the authoritarian government's adaptive capacities under changing circumstances. Further research is needed on local structures where state power encounters social resistance, producing as yet un-institutionalised processes of insecure compromise.
Challenges to Interdisciplinary Research in Ecosystem‐Based Management
Authors: SIEVANEN LEILA , CAMPBELL LISA M. , LESLIE HEATHER M.
Published: January 2012

Abstract:  Despite its necessity, integration of natural and social sciences to inform conservation efforts has been difficult. We examined the views of 63 scientists and practitioners involved in marine management in Mexico's Gulf of California, the central California coast, and the western Pacific on the challenges associated with integrating social science into research efforts that support ecosystem‐based management (EBM) in marine systems. We used a semistructured interview format. Questions focused on how EBM was developed for these sites and how contextual factors affected its development and outcomes. Many of the traditional challenges linked with interdisciplinary research were present in the EBM projects we studied. However, a number of contextual elements affected how mandates to include social science were interpreted and implemented as well as how easily challenges could be addressed. For example, a common challenge is that conservation organizations are often dominated by natural scientists, but for some projects it was easier to address this imbalance than for others. We also found that the management and institutional histories that came before EBM in specific cases were important features of local context. Because challenges differed among cases, we believe resolving challenges to interdisciplinary research should be context specific.
Treating Chronically Ill People with Diabetes Mellitus with Limited Life Expectancy: Implications for Performance Measurement
Authors: Woodard LeChauncy D. , Landrum Cassie R. , Urech Tracy H. , Profit Jochen , Virani Salim S. , Petersen Laura A.
Published: January 2012

Objectives

To develop an algorithm to identify individuals with limited life expectancy and examine the effect of limited life expectancy on glycemic control and treatment intensification in individuals with diabetes mellitus.

Design

Individuals with diabetes mellitus and coexisting congestive heart failure, chronic obstructive pulmonary disease, dementia, end‐stage liver disease, and/or primary or metastatic cancer with limited life expectancy were identified. To validate the algorithm, 5‐year mortality was assessed in individuals identified as having limited life expectancy. Rates of meeting performance measures for glycemic control between individuals with and without limited life expectancy were compared. In individuals with uncontrolled glycosylated hemoglobin (HbA1c) levels, the effect of limited life expectancy on treatment intensification within 90 days was examined.

Setting

One hundred ten Department of Veterans Affairs facilities; October 2006 to September 2007.

Participants

Eight hundred eighty‐eight thousand six hundred twenty‐eight individuals with diabetes mellitus.

Measurements

HbA1c; treatment intensification within 90 days of index HbA1c reading.

Results

Twenty‐nine thousand sixteen (3%) participants had limited life expectancy. Adjusting for age, 5‐year mortality was five times as high in participants with limited life expectancy than in those without. Participants with limited life expectancy had poorer glycemic control than those without (glycemic control: 77.1% vs 78.1%; odds ratio (OR) = 0.84, 95% confidence interval (CI) = 0.81–0.86) and less‐frequent treatment intensification (treatment intensification: 20.9% vs 28.6%; OR = 0.71, 95% CI = 0.67–0.76), even after controlling for patient‐level characteristics.

Conclusion

Participants with limited life expectancy were less likely than those without to have controlled HbA1c levels and to receive treatment intensification, suggesting that providers treat these individuals less aggressively. Quality measurement and performance‐based reimbursement systems should acknowledge the different needs of this population.
Customer‐Perceived Positioning Effectiveness: Conceptualization, Operationalization, and Implications for New Product Managers
Authors: Fuchs Christoph , Diamantopoulos Adamantios
Published: January 2012

An extensive body of literature documents that positioning is a central success factor for the launch and overall performance of new products in the marketplace. Under certain circumstances, however, the measurement of positioning success can be problematic. Specifically, the application of attribute‐based measurement methods, which are frequently used in practice for this purpose, is subject to limitations in certain situations. For example, these methods can be problematic in product categories where products are evaluated as a whole or where they even lack attributes that create valuable differentiation. Their application can also be difficult in product markets in which the importance of product attributes is constantly shifting or in a cross‐national context where the importance of various attributes is likely to differ across countries. This paper introduces a new approach for measuring positioning effectiveness that helps overcome some key limitations of extant approaches and serves as a support tool for positioning‐related decisions. Positioning effectiveness is modeled as a customer‐based multidimensional construct capturing conceptually relevant dimensions of positioning success (namely dissimilarity, uniqueness, favorability, and credibility) at the holistic product level rather than the individual attribute level. Altogether seven studies show that the proposed positioning effectiveness measure is reliable, valid, and viable to be used across various types of branded products and distinct product categories. The results of the studies indicate the measure's ability to successfully predict important consumer behavior variables such as overall superiority or purchase intentions and demonstrate superior predictive performance compared with common attribute‐based approaches. The recognition of the relevance of different dimensions of positioning effectiveness should also enable new product managers to detect strengths and weaknesses of a product's current positioning, and thus serve as a tool to develop more effective product strategies. The general nature of the measurement instrument makes it particularly suitable for application in (1) longitudinal product‐tracking studies; (2) cross‐national studies involving comparisons of positioning effectiveness between products in different countries; (3) product categories characterized by technological turbulence (and hence attribute instability); and (4) studies aimed at comparing the positioning effectiveness of different products in a portfolio. Boundary conditions for the application of the measure and potential areas for further study are finally considered.
Stage‐to‐Stage Information Dependency in the NPD Process: Effective Learning or a Potential Entrapment of NPD Gates?
Authors: Jespersen Kristina Risom
Published: January 2012

The new product development (NPD) process is a sequence of stages and gates. Each stage consists of NPD activities that provide NPD managers with information input about the new product project progression. Information input is used for review decisions at gates. Over the course of an NPD process, managers learn about a new product project as to ensure successful launch. The view is that a new product project is shaped by the path of NPD activities it has traveled. Because learning is assumed to take place over the course of the NPD process, stage‐to‐stage information dependency is an assumption of NPD research. A concern raised is that development activities for each NPD stage are rigorously followed by NPD managers. In other words, stage‐to‐stage information dependency may potentially trap NPD managers rather than create effective learning from end to end of the development process. The purpose of this paper is to explore the assumption of stage‐to‐stage information dependency in NPD. The investigated research questions are whether the selection of NPD activities is linked between stages and whether these information dependencies strengthen NPD gate decisions. For the information dependencies identified in the study, the innovation experience characteristics of NPD managers pursuing them and the influence of information dependencies on NPD gate decisions are analyzed so as to provide insights for a discussion of information dependency versus information independency in the NPD process. The applied research method is an experiential simulation of NPD gate decision‐making—NPDGATES. One hundred thirty‐one NPD managers from international product development strategic business units (SBUs) situated in Denmark participated in the study. Logistic regressions were conducted as the basis for the calculation of stage‐to‐stage information dependency probabilities. Based on the study findings, the assumption about information dependency in the NPD process held by NPD research is found to be flawed. End‐to‐end information paths in the NPD process are rare. Further, market condition changes are found to significantly influence the stage‐to‐stage information dependencies demonstrated by NPD managers. It seems that competition becomes a reassurance of NPD efforts. Also, the results show that NPD experience creates inflexibility in relation to the selection of NPD activities. The need for strict process management is strong among experienced NPD managers. In relation to NPD gates, the results show that information dependencies increase priority given to financial decision criteria at gates and lower priority given to customer and market decision criteria. Overall, stage‐to‐stage information dependency seems to create inflexibility that hinders successful NPD process implementation.
New Venture Performance in China, Japan, and the United States: The Impact of Formalized Market Information Processes
Authors: Kawakami Tomoko , MacLachlan Douglas L. , Stringfellow Anne
Published: January 2012

New venture companies, starting from small entities comprising entrepreneurs and their teams, start to grow in scale by instigating formalized processes to enhance management efficiency. This includes the use of formalized processes for collecting and disseminating market information. Despite the fact that utilizing market information is one of the fundamental factors of market orientation, little is known about the way market information is processed in new venture companies. The first aim of this research was to investigate the impact of formalized market information acquisition and utilization on new venture performance. The second objective was to investigate the effect of organizational formalization on the acquisition and utilization of market information in new venture firms. The final goal was to explore the extent to which these relationships vary in different cultural contexts. Based on an extensive literature review and interviews with managers in China, Japan, and the United States, a conceptual framework is developed that relates formalized market information processes to new venture performance in the three countries. The conceptual model is tested with data collected from 453 new venture companies in these countries. The results suggest that the use of a formalized process of market information utilization has a positive effect on new venture performance regardless of country. The analysis also indicates that the effect of organizational formalization, in general, differs between countries. Organizational formalization is associated with increased formalized utilization of market information only in the United States; the relationship does not apply in the two Asian countries studied. Taken together, these results suggest that in the Asian countries, organizational formalization improves information collection, while in the United States, it also improves the utilization of information throughout the organization. One implication of these results may be the potential of added benefits accruing to organizational formalization in new ventures in countries with high levels of individualism and/or high levels of power distance, where organizational power is concentrated in formal vertical reporting relationships, as opposed to informal horizontal peer‐to‐peer networks.
What Are the Effective Strategic Orientations for New Product Success under Different Environments? An Empirical Study of Chinese Businesses
Authors: Yang Yan , Wang Qing , Zhu Hengyuan , Wu Guisheng
Published: January 2012

Innovation is an organization's spanning process that must continually change in response to, and in anticipation of, changing business environments. Research in the fields of marketing and management has examined individual strategic orientations (SOs) (such as market orientation) and their relationship to innovation performance. Few studies, however, have compared the effectiveness of different SOs for innovation performance in a single study. It is also not clear from previous research whether the business environment influences the effectiveness of the SOs. The objective of this paper is therefore twofold: it aims to evaluate (1) whether a focus on the customer, the technology, the competitor, or the interfunctional coordination, will have the greatest impact on new product success, and (2) whether the effectiveness of a specific SO varies with the environment. Data were collected from more than 500 senior executives in a wide range of manufacturing and service firms in China. Using cluster analysis and an ordinary least squares (OLS) regression model, which are commonly adopted to examine the effects of environments on the relationship between strategy and performance, we identified four subgroups of firms facing distinctively different market and competitive environments. As predicted, the results show that all four SOs have (albeit to a different degree) a significant and positive relationship with innovation performance. More importantly, the results point to the relative advantage in pursuing a specific SO by taking into account its effect under different environments and the effects of other SOs. However, the particularly strong effect of technology orientation compared to that of the other SOs on new product performance across all clusters is somewhat surprising. We offer some tentative explanations for this finding, though further research will be required to fully understand it. Overall, our findings indicate the need for managers to be responsive to environmental contexts and to allocate resources to pursue the effective (hence appropriate) strategic orientations for the specific context.
From There to Here: Punctuated Equilibrium to the General Punctuation Thesis to a Theory of Government Information Processing
Authors: Jones Bryan D. , Baumgartner Frank R.
Published: January 2012

In this introduction to the Policy Study Journal's special issue on punctuated equilibrium, we provide an overview of the approach, how it evolved, some of the major critiques directed at it, and some of the major developments it has spawned. We argue that the most important aspect of a theory or framework is not whether it is right or wrong, but the extent to which it is fruitful; that is, the extent to which it stimulated further research. Finally, we review the articles in this issue and put them in context.
Pet Sounds: Subsystems, Regimes, Policy Punctuations, and the Neglect of African American Farmers, 1935–2006
Authors: Worsham Jeff , Stores Chaun
Published: January 2012

Punctuated equilibrium theory (PET) has reoriented the study of public policy and American politics in particular. In this study, we documented how a policy punctuation that appears to take hold at the macro level of the polity in the form of a policy regime has difficulty penetrating subsystem politics. We drew on subsystems theory, PET, and the latest work on policy regimes to document the resistance of the agriculture subsystem to efforts to add a civil rights dimension to agriculture policy between 1935 and 2006. We concluded that the issue evolution of agricultural support programs, and their insulation from civil rights policy, is a prime example of how subsystems use negative feedback to resist change.
Amniotic membrane‐derived cells inhibit proliferation of cancer cell lines by inducing cell cycle arrest
Authors: Magatti Marta , De Munari Silvia , Vertua Elsa , Parolini Ornella
Published: January 2012

Cells derived from the amniotic foetal membrane of human term placenta have drawn particular attention mainly for their plasticity and immunological properties, which render them interesting for stem‐cell research and cell‐based therapeutic applications. In particular, we have previously demonstrated that amniotic mesenchymal tissue cells (AMTC) inhibit lymphocyte proliferation in vitro and suppress the generation and maturation of monocyte‐derived dendritic cells. Here, we show that AMTC also significantly reduce the proliferation of cancer cell lines of haematopoietic and non‐haematopoietic origin, in both cell–cell contact and transwell co‐cultures, therefore suggesting the involvement of yet‐unknown inhibitory soluble factor(s) in this ‘cell growth restraint’. Importantly, we provide evidence that the anti‐proliferative effect of AMTC is associated with induction of cell cycle arrest in G0/G1 phase. Gene expression analyses demonstrate that AMTC can down‐regulate cancer cells' mRNA expression of genes associated with cell cycle progression, such as cyclins (cyclin D2, cyclin E1, cyclin H) and cyclin‐dependent kinase (CDK4, CDK6 and CDK2), whilst they up‐regulate cell cycle negative regulator such as p15 and p21, consistent with a block in G0/G1 phase with no progression to S phase. Taken together, these findings warrant further studies to investigate the applicability of these cells for controlling cancer cell proliferation in vivo.
Upward shift in elevational plant species ranges in Sikkilsdalen, central Norway
Authors: Felde Vivian Astrup , Kapfer Jutta , Grytnes John‐Arvid
Published: January 2012

Phytosociological studies can be an important tool to detect temporal vegetation changes in response to global climate change. In this study, we present the results of a resurvey of a plot‐based phytosociological study from Sikkilsdalen, central Norway, originally executed between 1922 and 1932. By using a detailed phytosociological study we are able to investigate several aspects of elevational shifts in species ranges. Here we tested for upward and downward shifts in observed upper and lower distribution limits of species, as well as changes in species optima along an elevational gradient, and related the observed range shifts to species traits that could explain the observed trends.

More species shifted upwards than downwards, independently of whether we were investigating shifts in species’ upper or lower distribution ranges or in species optima. However, shifts in species upper range margins changed independently of their lower range margins. Linking different species traits to the magnitude of shifts we found that species with a higher preference for prolonged snow cover shifted upwards more in their upper elevational limits and in their optima than species that prefer a shorter snow cover, whereas no species traits were correlated with the magnitude of changes in lower limits.

The observed change in species ranges concord both with studies on other mountains in the region and with studies from other alpine areas. Furthermore, our study indicates that different factors are influencing species ranges at the upper and lower range limits. Increased precipitation rates and increased temperatures are considered the most important factors for the observed changes, probably mainly through altering the pattern in snow cover dynamics in the area.
Biogeographical contrasts to assess local and regional patterns of invasion: a case study with two reciprocally introduced exotic maple trees
Authors: Lamarque Laurent J. , Delzon Sylvain , Sloan Margaret H. , Lortie Christopher J.
Published: January 2012

Quantitative comparisons of distribution and abundance of exotic species in their native and non‐native ranges represent a first step when studying invaders. However, this approach is rarely applied 2 particularly to tree species. Using biogeographical contrasts coupled with regional dispersal surveys, we assessed whether two exotic maple tree species, Acer negundo and Acer platanoides, can be classified as invasive in the non‐native regions surveyed. We also examined the importance of biogeography in determining the degree of invasion by exotic species using this reciprocal approach. Local‐scale surveys were conducted in a total of 34 forests to compare density, relative abundance, age structure of native and introduced populations, and whether the two introduced maple species negatively affected native tree species density. Regional‐scale surveys of a total of 136 forests were then conducted to assess distribution in the introduced regions. Introduced populations of A. negundo were denser than populations measured in their native range and negatively related to native tree species density. Age structure did not differ between regions for this species. At the regional scale, this species has invaded most of the riparian corridors sampled in France. Conversely, the density of A. platanoides introduced populations was similar to that of native populations and was not related to native tree species density. Although seedling recruitment was higher away than at home, this species has invaded only 9% of the forests sampled in southern Ontario, Canada. Although reported invasive, these two exotic maple species differed in their relative demographic parameters and regional spread. Acer negundo is currently invasive in southern France while A. platanoides is not aggressively invasive in southern Ontario. Importantly, this study effectively demonstrates that biogeography through structured contrasts provide a direct means to infer invasion of exotic species.
Immune tolerance induction in patients with severe hemophilia with inhibitors: expert panel views and recommendations for clinical practice
Authors: Benson Gary , Auerswald Günter , Elezović Ivo , Lambert Thierry , Ljung Rolf , Morfini Massimo , Remor Eduardo , Šalek Silva Zupančić
Published: January 2012

For hemophilia patients with inhibitors, immune tolerance induction (ITI) may help to restore clinical response to factor (F) VIII or FIX concentrates. Several ITI regimens and protocols exist; however, despite 30 yr of progressive investigation, the ITI evidence base relies mainly on observational data. Expert opinion, experience, and interpretation of the available evidence are therefore valuable to support clinical decision‐making. At the Sixth Zürich Haemophilia Forum, an expert panel considered recent data and consensus to distill key practice points relating to ITI. The panel supported current recommendations that, where feasible, ITI should be offered early to children and adults (ideally ≤5 yr of inhibitor detection) when inhibitor titers are <10 Bethesda units (BU) and should be stopped when successful tolerance is achieved. For hemophilia A inhibitor patients, ITI can be founded on recombinant FVIII at high doses. The panel considered that patients with a high bleeding frequency should be offered additional prophylaxis with a bypassing agent. For patients with hemophilia B, there may be a benefit of genetic testing to indicate the risk for inhibitors. ITI is often less effective and associated with a greater risk of side effects in these patients. For high‐titer inhibitor (≥5 BU) hemophilia B patients, the panel advised that bypassing agents could be offered on demand in addition to ITI. Within future ITI regimens, there may be a role for additional immunosuppressant therapies. Participants agreed that research is needed to find alternatives to ITI therapy that offer durable and sustained effects and reduced rates of complications.
Intrinsic predictive factors for ankle sprain in active university students: A prospective study
Authors: de Noronha M. , França L. C. , Haupenthal A. , Nunes G. S.
Published: January 2012

The ankle is the joint most affected among the sports‐related injuries. The current study investigated whether certain intrinsic factors could predict ankle sprains in active students. The 125 participants were submitted to a baseline assessment in a single session were then followed‐up for 52 weeks regarding the occurrence of sprain. The baseline assessment were performed in both ankles and included the questionnaire Cumberland ankle instability tool – Portuguese, the foot lift test, dorsiflexion range of motion, Star Excursion Balance Test (SEBT), the side recognition task, body mass index, and history of previous sprain. Two groups were used for analysis: one with those who suffered an ankle sprain and the other with those who did not suffer an ankle sprain. After Cox regression analysis, participants with history of previous sprain were twice as likely to suffer subsequent sprains [hazard ratio (HR) 2.21 and 95% confidence interval (CI) 1.07–4.57] and people with better performance on the SEBT in the postero‐lateral (PL) direction were less likely to suffer a sprain (HR 0.96 and 95% CI 0.92–0.99). History of previous sprain was the strongest predictive factor and a weak performance on SEBT PL was also considered a predictive factor for ankle sprains.
Isometric handgrip training lowers blood pressure and increases heart rate complexity in medicated hypertensive patients
Authors: Millar P. J. , Levy A. S. , McGowan C. L. , McCartney N. , MacDonald M. J.
Published: January 2012

Hypertension is characterized by elevated blood pressure (BP) and autonomic dysfunction, both thought to be improved with exercise training. Isometric handgrip (IHG) training may represent a beneficial, time‐effective exercise therapy. We investigated the effects of IHG training on BP and traditional and nonlinear measures of heart rate variability (HRV). Pre‐ and post‐measurements of BP and HRV were determined in 23 medicated hypertensive participants (mean ± SEM, 66 ± 2 years) following either 8 weeks of IHG training (n = 13) or control (n = 10). IHG exercise consisted of four unilateral 2‐min isometric contractions at 30% of maximal voluntary contraction, each separated by 4 min of rest. IHG training was performed 3 days/week for 8 weeks. IHG training decreased systolic BP (125 ± 3 mmHg to 120 ± 2 mmHg, P < 0.05) and mean BP (90 ± 2 mmHg to 87 ± 2 mmHg, P < 0.05), while sample entropy was increased (1.07 ± 0.1 to 1.35 ± 0.1, P < 0.05) and the fractal scaling distance score was decreased (0.34 ± 0.1 to 0.19 ± 0.1, P < 0.05). No significant changes were observed in traditional spectral or time‐domain measures of HRV or control participants. IHG training improves nonlinear HRV, but not traditional HRV, while reducing systolic and mean BP. These results may highlight the benefits of IHG training for patients with primary hypertension.
Effects of local osteoprotegerin gene transfection on orthodontic root resorption during retention: an in vivo micro‐CT analysis
Authors: Zhao N. , Liu Y. , Kanzaki H. , Liang W. , Ni J. , Lin J.
Published: January 2012

Zhao N., Liu Y., Kanzaki H., Liang W., Ni J., Lin J. Effects of local osteoprotegerin gene transfection on orthodontic root resorption during retention: an in vivo micro‐CT analysis.  Orthod Craniofac Res 2012;15:10–20 © John Wiley & Sons A/S

Structured Abstract

Objectives –  External root resorption (ERR) is a serious complication of orthodontic treatment. Aim of this study was to evaluate the effects of local osteoprotegerin (OPG) gene transfection on ERR during retention.

Material and Methods –  Eighteen 6‐week‐old male Wistar rats were divided into three groups. All the rats were subjected to 2 weeks of orthodontic tooth movement followed by a 2‐week retention period. During retention, the three groups of rats received local OPG gene transfection (OPG transfection group, n = 6), mock vector transfection (mock group, n = 6), or no injections (control group, n = 6). ERR of all three groups was evaluated with in vivo micro‐CT analysis at three different time points: baseline, the last day of orthodontic tooth movement, and the last day of retention.

Results –  In the OPG transfection group, there was no significant difference between ERR at the baseline and ERR on the last day of retention. By the last day of retention, the repair ratio of ERR in the OPG transfection group was statistically higher in relation to the repair ratio of the other groups (p < 0.001).

Conclusion –  The results indicated that local OPG gene transfection significantly enhanced the repair of ERR during retention. Local OPG gene transfection might therefore be a useful tool for ERR repair during retention.
Orthopedic protraction of the maxilla may affect cranial base synchondroses indicated by increased expressions of growth factors
Authors: Feng J. , Zhao N. , Zhao J. , Rabie A. B. , Shen G.
Published: January 2012

Feng J., Zhao N., Zhao J., Rabie A. B., Shen G. Orthopedic protraction of the maxilla may affect cranial base synchondroses indicated by increased expressions of growth factors.  Orthod Craniofac Res 2012;15:62–70 © John Wiley & Sons A/S

Structured Abstract

Objectives –  To examine the biological adaptation of cranial base synchondroses (CBS) when the maxilla was forward positioned by orthopedic force.

Setting and Sample Population –  The Department of Orthodontics at Shanghai Jiao Tong University. 50 Sprague–Dawley rats, 4 weeks of age, were divided into experimental (n = 30) and control groups (n = 20).

Material and Methods –  An orthopedic appliance was fitted to the cranio‐maxillary complex to advance the maxilla forward. The animals in the experimental group, together with the counterparts in the control group, were sacrificed at days 1, 3, 5, 7, and 14, respectively. The whole cranial base housing both the spheno‐ethmoid (SES) and spheno‐occipital synchondroses (SOS) was removed for tissue processing and immunotest of Sox9, Core‐binding factor α 1 (Cbfa1), and vascular endothelial growth factor (VEGF), three carefully selected growth factors that are markers of chondrogenesis in different stages and its transition to endochondral ossification. Semiquantitative analysis was also conducted by using a computerizing imaging system.

Results –  The temporal tendency of the changes in the expressions of the three growth factors featured an increase from Day 3 and onwards for Cbfa1 and VEGF, and a following decline after Day 5 for Sox9. In both SES and SOS, the expressions of the three growth factors were significantly stronger in the experimental groups than that in groups (p < 0.05).

Conclusions –  Protractive orthopedic force imposed on the maxilla provokes an enhancement of chondrogenic process in CBS.
Spatial pattern and composition of the Florida scrub seed bank and vegetation along an anthropogenic disturbance gradient
Authors: Navarra Jennifer J. , Quintana‐Ascencio Pedro F.
Published: January 2012

Question

How does spatial pattern and composition of the seed bank and its relationship to above‐ground cover vary across an anthropogenic disturbance gradient of intact Florida rosemary scrub, degraded scrub and improved pasture?

Location

Florida rosemary scrub, Lake Wales Ridge, Highlands County, FL, USA (27° 11′N, 81° 21′W).

Methods

In nine grid plots located in intact Florida rosemary scrub, degraded scrub and improved pasture, we assessed percentage vegetation cover and seed bank composition.

Results

The vegetation was dominated by long‐lived perennials, while the seed bank was dominated by short‐lived species. Shrubs were the dominant above‐ground cover in rosemary scrub, sub‐shrubs and the spike moss Selaginella arenicola in degraded scrub and non‐native grasses in pastures. Scrub forbs were dominant in the seed bank of rosemary scrub, similar amounts of sedges, ruderal forbs and scrub forbs in degraded scrub, and ruderal species and sedges in pastures. Species absent from the vegetation were randomly distributed in the seed bank, while species present above‐ground had an aggregated spatial distribution. In rosemary scrub, scrub forb seed banks were spatially aggregated and were positively associated with conspecific species above‐ground and with litter cover. These patterns were not observed in degraded scrub, perhaps due to reduced shrub and increased bare ground.

Conclusion

Our results suggest that reduced shrub cover and increased bare ground in the degraded scrub may explain why there is less spatial aggregation of scrub forbs in the seed bank. Restoration of Florida rosemary scrub in pasture sites will require species reintroduction of appropriate scrub species; restoration of degraded scrub should emphasize increasing shrub cover to restore habitat spatial structure.
The kynurenine pathway and quinolinic acid: pivotal roles in HIV associated neurocognitive disorders
Authors: Kandanearatchi Apsara , Brew Bruce J.
Published: January 2012

This brief review will first consider HIV associated neurocognitive disorder followed by the current understanding of its neuropathogenesis. Against this background the role of the kynurenine pathway will be detailed. Evidence both direct and indirect will be discussed for involvement of the kynurenine pathway at each step in the neuropathogenesis of HIV associated neurocognitive disorder.
A Molecular Carrier to Transport and Deliver Cisplatin into Endometrial Cancer Cells
Authors: Borrelli Antonella , Schiattarella Antonietta , Musella Alessandra , Mancini Roberto , Capasso Clemente , De Luca Viviana , Carginale Vincenzo , Sanseverino Marina , Tornesello Anna Lucia , Gori Enrico , Pica Alessandra , Di Santi Annalisa , Basile Filomena , Iacobellis Francesca , Colacurci Nicola , Cobellis Luigi , Mancini Aldo
Published: January 2012

The leader peptide of a recombinant manganese superoxide dismutase (rMnSOD‐Lp) acts as a molecular carrier. Clonogenic tests on normal (MRC‐5) and endometrial adenocarcinoma cells (HTB‐112) were carried out in the presence of rMnSOD‐Lp, cisplatin alone (CC) or cisplatin conjugated to the rMnSOD‐Lp (rMnSOD‐Lp‐CC). The platinum delivered into the cells was measured by atomic spectrophotometric absorbance. The treatments on tumor and normal cells were finally evaluated by LM and TM microscopy. Tumor cell death in the case of 0.5 μm cisplatin on its own was minimal, while in the presence of 0.5 μm rMnSOD‐Lp‐CC, no tumor cells survived. Atomic absorbance analysis showed that rMnSOD‐Lp‐CC delivered approximately four times more cisplatin into HTB‐112 cells than the amount delivered using cisplatin alone. By LM observation, the cells treated with rMnSOD‐Lp‐CC showed signs of nuclear and cytoplasmic fragmentation, that is, apoptosis induced by the treatment. The therapeutic effect of rMnSOD‐Lp‐CC on endometrial cancer cells was significant, while on the normal cells it showed only a minimal toxicity. We believe that rMnSOD‐Lp deserves to be considered as a molecular carrier to deliver cisplatin directly into tumor cells, thus transforming its antireplicative activity into a specific and selective antitumor agent.
Induction of gut IgA production through T cell‐dependent and T cell‐independent pathways
Authors: Bemark Mats , Boysen Preben , Lycke Nils Y.
Published: January 2012

The gut immune system protects against mucosal pathogens, maintains a mutualistic relationship with the microbiota, and establishes tolerance against food antigens. This requires a balance between immune effector responses and induction of tolerance. Disturbances of this strictly regulated balance can lead to infections or the development inflammatory diseases and allergies. Production of secretory IgA is a unique effector function at mucosal surfaces, and basal mechanisms regulating IgA production have been the focus of much recent research. These investigations have aimed at understanding how long‐term IgA‐mediated mucosal immunity can best be achieved by oral or sublingual vaccination, or at analyzing the relationship between IgA production, the composition of the gut microbiota, and protection from allergies and autoimmunity. This research has lead to a better understanding of the IgA system; but at the same time seemingly conflicting data have been generated. Here, we discuss how gut IgA production is controlled, with special focus on how differences between T cell‐dependent and T cell‐independent IgA production may explain some of these discrepancies.