bluuebunny/crossref_metadata_2025_split huggingface dataset:
Beta-adrenergic Modulation of Cognitive Flexibility during Stress
Authors: Alexander Jessica K. , Hillier Ashleigh , Smith Ryan M. , Tivarus Madalina E. , Beversdorf David Q. 
Published: March 2007

Abstract
Stress-induced activation of the locus ceruleus-norepinephrine (LC-NE) system produces significant cognitive and behavioral effects, including enhanced arousal and attention. Improvements in discrimination task performance and memory have been attributed to this stress response. In contrast, for other cognitive functions that require cognitive flexibility, increased activity of the LC-NE system may produce deleterious effects. The aim of the present study was to determine the effect of pharmacological modulation of the LC-NE system on stress-induced impairments in cognitive flexibility performance in healthy individuals. Cognitive performance, plus psychological and physiological parameters for 16 adults without any history of anxiety disorders, was assessed during four test sessions: stress and no-stress, with each condition tested after administration of propranolol and placebo. The Trier Social Stress Test, a public-speaking and mental arithmetic stressor, was presented to participants for the stress sessions, whereas a similar, but nonstressful, control task (reading, counting) was utilized for the no-stress sessions. Tests of cognitive flexibility included lexical-semantic and associative problem-solving tasks (anagrams, Compound Remote Associates Test). Visuo-spatial memory and motor processing speed tests served as control tasks. Results indicate that (1) stress impaired performance on cognitive flexibility tasks, but not control tasks; (2) compared to placebo, cognitive flexibility improved during stress with propranolol. Therefore, psychological stress, such as public speaking, negatively impacts performance on tasks requiring cognitive flexibility in normal individuals, and this effect is reversed by beta-adrenergic antagonism. This may provide support for the hypothesis that stress-related impairments in cognitive flexibility are related to the noradrenergic system.
Placing the Wild in the City: "Thinking with" Melbourne's Bats
Authors: Thomson Melanie 
Published: March 2007

AbstractThis paper uses academic and lay discourses to examine the ways in which "the city" is constructed in its relationship to "wildlife." The paper examines the negative and essentialized ways in which the city's relationship to wildlife has been represented in postcolonial theory and animal geography. The paper further explores these theoretical framings of the city in the empirical context of the relocation of an urban, flying fox colony, which provides opportunities to reconsider these bounded conceptualizations of the city.
Public Opinion and Foreign Threats: Eisenhower's Response to Sputnik
Authors: Payne Rodger A. 
Published: March 2007

Renewed attention to the role of public opinion on foreign policy outcomes in quantitative correlational studies indicates that opinion influences foreign policy. However, authors of these studies note that their conclusions could be flawed if elites simply manipulate public opinion, rather than responding to it. Both realist and neorealist perspectives on public opinion are consistent with a manipulation perspective. As urged by those using quantitative data, this article examines a case using declassified archival information in order to examine responsiveness in a situation ripe for manipulation. Specifically, U.S. reactions to Soviet Sputnik launches are scrutinized. President Eisenhower was much less concerned about Soviet actions than was the general public but nonetheless substantially altered many defense programs in order to meet perceived public demands. The President acknowledged privately that at least two-thirds of a spending supplement was used to meet public fears, not real security needs. This finding is inconsistent with prevailing realist theories and standard historical interpretations.
The Army's War against Malaria: Collaboration in Drug Research during World War II
Authors: Condon-Rall Mary Ellen 
Published: March 2007

During the second half of World War II, U.S. and Allied military and civilian scientists cooperated in helping the armed forces combat malaria. They worked through the Offices of the Surgeon General of the U.S. Army and the U.S. Navy, the National Research Council, the Board for the Coordination of Malarial Studies, the Office of Scientific Research and Development, the Australian Military Mission, and the British Medical Research Council, all in Washington, D.C. The Board for the Coordination of Malarial Studies, which the National Research Council established in November 1943 to guide research expansion and coordinate joint efforts, became the focal point for collaboration on research. These alliances produced hundreds of malaria studies and thousands of new compounds, some of which tested superior to traditional antimalarial drugs. This cooperative effort improved chemotherapy for the prevention and treatment of malaria after years of neglect in the development of antimalarial drugs. This article focuses on the establishment of the Board for the Coordination of Malarial Studies, the development of new antimalarial drugs, and collaboration with allies on drug research. The latter produced special U.S.-Australian and U.S.-Britain relationships.
Political Violence and Time in ower
Authors: Whitten Guy D. , Bienen Henry S. 
Published: March 2007

With this article we hope to add something new to explanations for violence within polities. We examine the consequences of time in power for political violence. We are interested in the length of time a leader is in power and the time when political violence occurs. We start with a simple hypothesis: the longer a leader is in power, the less likely it is that there will be occurrences of large-scale political violence. We are not aware of any theories of violence that have taken account of leadership duration. We do not argue below that leadership duration and the timing of violence explain all variation in violent political outcomes. Rather, it is our assertion that theories of violence have ignored an important factor: the length of time that a leader has been in power. Throughout the analyses presented in this article we have found a relationship between the number of years a leader has been in power and the probability and volume of political violence that the nation that they are governing is likely to experience. As the length of a leader's time in power increases, the probability of political violence declines. This relationship has been demonstrated to be significant in both statistical and substantive terms in a number of different statistical settings that make a variety of assumptions about the quality of the data we are working with and the underlying relationships we are investigating.
Investment or Overkill: Should Military Child Development Centers Be Accredted?
Authors: Zellman Gail L. , Johansen Anne S. 
Published: March 2007

This study examines whether accreditation of military child development centers (CDCs) pays off in a context of rigorous quality standards and aggressive compliance monitoring under the Military Child Care Act (MCCA) of 1989. To collect information about the value of accreditation, we reviewed accreditation standards and inspection documents, fielded a military-wide survey of child development directors, and conducted one-on-one interviews at four Major Commands and on 17 installations with Command, Morale, Welfare, and Recreation (MWR), child development, and youth activities staff. We found that while the four annual unannounced inspections that the MCCA requires of each CDC have substantially improved staffing, facility quality, and health and safety procedures, the inspection process focuses on compliance with largely structural standards that are relatively easily monitored. In contrast, the accreditation process focuses on interactive aspects of caregiving and actively engages caregivers in self-evaluation designed to improve their caregiving behavior. Although we could not directly assess the impact of accreditation on children's outcomes, there was near-consensus that improvements in caregiving precipitated by the accreditation process benefit children. Given minimal incremental costs, we conclude that universal accreditation is desirable and achievable.
Ligand density dramatically affects integrin αIIbβ3-mediated platelet signaling and spreading
Authors: Jiroušková Markéta , Jaiswal Jyoti K. , Coller Barry S. 
Published: March 2007

AbstractThe impact of ligand density on integrin-mediated cell adhesion and outside-in signaling is not well understood. Using total internal reflection fluorescent microscopy, conformation-specific antibodies, and Ca2+ flux measurements, we found that the surface density of fibrinogen affects αIIbβ3-mediated platelet signaling, adhesion, and spreading. Adhesion to fibrinogen immobilized at low density leads to rapid increases in cytosolic Ca2+ and sequential formation of filopodia and lamellipodia. In contrast, adhesion to high-density fibrinogen results in transient or no increases in Ca2+ and simultaneous formation of filopodia and lamellipodia. αIIbβ3 receptors at the basal surface of platelets engage fibrinogen in a ringlike pattern at the cell edges under both conditions. This engagement is, however, more dynamic and easily reversed on high-density fibrinogen. Src and Rac activity and actin polymerization are important for adhesion to low-density fibrinogen, whereas PKC/PI3 kinases contribute to platelet spreading on high-density fibrinogen. We conclude that 2 fundamentally different signaling mechanisms can be initiated by a single integrin receptor interacting with the same ligand when it is immobilized at different densities.
Gossypin, a pentahydroxy glucosyl flavone, inhibits the transforming growth factor beta-activated kinase-1-mediated NF-κB activation pathway, leading to potentiation of apoptosis, suppression of invasion, and abrogation of osteoclastogenesis
Authors: Kunnumakkara Ajaikumar B. , Nair Asha S. , Ahn Kwang Seok , Pandey Manoj K. , Yi Zhengfang , Liu Mingyao , Aggarwal Bharat B. 
Published: March 2007

AbstractGossypin, a flavone originally isolated from Hibiscus vitifolius, has been shown to suppress angiogenesis, inflammation, and carcinogenesis. The mechanisms of these activities, however, are unknown. Because nuclear factor-κB (NF-κB) is associated with inflammation, carcinogenesis, hyperproliferation, invasion, and angiogenesis, we hypothesized that gossypin mediates its effects through modulation of NF-κB activation. In the present study, we demonstrate that gossypin (and not gossypetin, an aglycone analog) inhibited NF-κB activation induced by inflammatory stimuli and carcinogens. Constitutive NF-κB activation in tumor cells was also inhibited by this flavone. Inhibition of IκBα kinase by gossypin led to the suppression of IκBα phosphorylation and degradation, p65 nuclear translocation, and NF-κB-regulated gene expression. This, in turn, led to the down-regulation of gene products involved in cell survival (IAP2, XIAP, Bcl-2, Bcl-xL, survivin, and antiFas-associated death domain–like interleukin-1β–converting enzyme-inhibitory protein), proliferation (c-myc, cyclin D1, and cyclooxygenase-2), angiogenesis (vascular endothelial growth factor), and invasion (matrix metalloprotease-9). Suppression of these gene products by gossypin enhanced apoptosis induced by tumor necrosis factor and chemotherapeutic agents, suppressed tumor necrosis factor–induced cellular invasion, abrogated receptor activator of NF-κB ligand–induced osteoclastogenesis, and vascular endothelial growth factor–induced migration of human umbilical vein endothelial cells. Overall, our results demonstrate that gossypin inhibits the NF-κB activation pathway, which may explain its role in the suppression of inflammation, carcinogenesis, and angiogenesis.
Noninvasive ventilation during walking in patients with severe COPD: a randomised cross-over trial
Authors: Dreher M. , Storre J. H. , Windisch W. 
Published: March 2007

It was hypothesised that noninvasive positive-pressure ventilation (NPPV) applied during walking prevents exercise-induced hypoxaemia and improves exercise performance in severe chronic obstructive pulmonary disease (COPD) patients already receiving long-term NPPV.A total of 20 COPD patients (mean±sdage 65.1±8.7 yrs, forced expiratory volume in one second 27±8% predicted and total lung capacity 116±27% pred) reporting dyspnoea, even during mild exertion, underwent two 6-min walking tests with a rollator and supplemental oxygen (2.1±0.9 L·min−1) in a randomised cross-over design: with and without pressure-limited NPPV as used at home (inspiratory:expiratory pressure 2.9±0.44:0.4±0.1 kPa (29±4:4±1 mbar), respiratory frequency 20±2 breaths·min−1).The arterial oxygen tension significantly increased by 1.39±1.43 kPa (95% confidence interval (CI) 0.71–2.07 kPa) after walking with NPPV, but significantly decreased by 1.43±1.06 kPa (95% CI −1.92 – −0.94 kPa) without NPPV. Dyspnoea, as assessed by the Borg dyspnoea scale, significantly decreased from 6 (interquartile range (IQR) 4.5–10) to 4 (1.5–4.5) and walking distance significantly increased from 209 (IQR 178–279) to 252 (203–314) m when walking was NPPV-aided.In chronic hypercapnic chronic obstructive pulmonary disease, high-intensity noninvasive positive-pressure ventilation can also be administered during walking with unchanged ventilator settings compared with settings used at rest, thus resulting in improved oxygenation, decreased dyspnoea and increased walking distance. Therefore, noninvasive positive-pressure ventilation during walking could prevent hypoxia-induced complications and could, in future, play a role in palliative care.
Cellular origin of pro-coagulant and (anti)-fibrinolytic factors in bleomycin-injured lungs
Authors: Wygrecka M. , Markart P. , Ruppert C. , Petri K. , Preissner K. T. , Seeger W. , Guenther A. 
Published: March 2007

Excessive pro-coagulant and decreased fibrinolytic activities in the alveolar compartment have been repeatedly documented for inflammatory and fibrotic lung diseases. The current authors determined the contribution of different resident lung cells to the altered local production of coagulation- and fibrinolysis-system components in bleomycin-injured mouse lungsviacell-specific and quantitative assessment of mRNA levels of various pro-coagulant and (anti)-fibrinolytic factors.Laser-assisted microdissection technology was used to sample specific cell populations in combination with subsequent mRNA analysis by real-time quantitative reverse transcriptase-PCR. Additionally, western blot analysis, immunohistochemistry and activity assays were performed.Following bleomycin challenge, the strongest induction of tissue factor and plasminogen activator inhibitor (PAI)-1 mRNA expression was observed in alveolar macrophages (∼250- and 60-fold induction, respectively). These factors were also upregulated in alveolar type II cells, but to an approximately six-fold lesser extent. In contrast, PAI-2 expression was induced exclusively in alveolar macrophages. A slight increase of urokinase-type plasminogen activator (uPA) expression was also observed in alveolar macrophages (two-fold induction), but uPA activity was reduced due to a disproportionate increase of PAI production.Alveolar macrophages and, to a lesser extent, alveolar type II cells are the main sources of locally produced pro-coagulant and anti-fibrinolytic factors in bleomycin-injured lungs.
Bacteria and mould components in house dust and children's allergic sensitisation
Authors: Gehring U. , Heinrich J. , Hoek G. , Giovannangelo M. , Nordling E. , Bellander T. , Gerritsen J. , de Jongste J. C. , Smit H. A. , Wichmann H-E. , Wickman M. , Brunekreef B. 
Published: March 2007

It has been suggested that early childhood exposure to microbial agents decreases the risk of allergies in children. The current authors studied the association between microbial agents in house dust and allergic sensitisation in children aged 2–4 yrs.Nested case-control studies were performed within ongoing birth cohort studies in Germany, the Netherlands and Sweden and ∼180 sensitised and 180 nonsensitised children were selected per country. Levels of bacterial endotoxin, β(1,3)-glucans and fungal extracellular polysaccharides (EPS) were measured in dust samples from the children’s mattresses and the living-room floors.Combined across countries, higher amounts of mattress dust and higher mattress dust loads of endotoxin, β(1,3)-glucans and EPS were associated with a significantly decreased risk of sensitisation to inhalant allergens. After mutual adjustment, only the protective effect of the amount of mattress dust remained significant (odds ratio (95% confidence interval) 0.57(0.39–0.84)).Higher amounts of mattress dust may decrease the risk of allergic sensitisation to inhalant allergens. The effect might be partly attributable to endotoxin, β(1,3)-glucans and extracellular polysaccharides, but could also reflect (additional) protective effects of (microbial) agents other than the ones measured. It is not possible to distinguish with certainty which component relates to the effect, since their levels are highly correlated.
Mechanism of G1 arrest in the Drosophilaeye imaginal disc
Authors: Escudero Luis M , Freeman Matthew 
Published: March 2007

Abstract
Background
Most differentiating cells are arrested in G1-phase of the cell cycle and this proliferative quiescence appears important to allow differentiation programmes to be executed. An example occurs in the Drosophila eye imaginal disc, where all cells are synchronized and arrested in G1 phase prior to making a fate choice either to initiate the first round of photoreceptor differentiation or to re-enter one terminal mitosis.

Results
We have analysed the mechanism of this temporally regulated G1-phase in order to develop an integrated model of this proliferative regulation. We find that an overlapping set of cell cycle inhibitors combine to form an efficient barrier to cell cycle progression. This barrier depends on both the primary secreted signals that drive retinal development, Dpp and Hh. Each of these has distinct, as well as partially overlapping functions, in ensuring that Cyclin E and dE2F1 are kept in check. Additionally, inhibition of Cyclin A by Roughex is essential, and this regulation is independent of Dpp and Hh.

Conclusion
One implication of these results is to further support the idea that Cyclin A has important functions in S-phase entry as well as in mitosis. The unexpectedly complex network of regulation may reflect the importance of cells being uniformly ready to respond to the inductive signals that coordinate retinal differentiation.
Silencing of beta-carotene hydroxylase increases total carotenoid and beta-carotene levels in potato tubers
Authors: Diretto Gianfranco , Welsch Ralf , Tavazza Raffaela , Mourgues Fabienne , Pizzichini Daniele , Beyer Peter , Giuliano Giovanni 
Published: March 2007

Abstract

Background
Beta-carotene is the main dietary precursor of vitamin A. Potato tubers contain low levels of carotenoids, composed mainly of the xanthophylls lutein (in the beta-epsilon branch) and violaxanthin (in the beta-beta branch). None of these carotenoids have provitamin A activity. We have previously shown that tuber-specific silencing of the first step in the epsilon-beta branch, LCY-e, redirects metabolic flux towards beta-beta carotenoids, increases total carotenoids up to 2.5-fold and beta-carotene up to 14-fold.

Results
In this work, we silenced the non-heme beta-carotene hydroxylases CHY1 and CHY2 in the tuber. Real Time RT-PCR measurements confirmed the tuber-specific silencing of both genes . CHY silenced tubers showed more dramatic changes in carotenoid content than LCY-e silenced tubers, with beta-carotene increasing up to 38-fold and total carotenoids up to 4.5-fold. These changes were accompanied by a decrease in the immediate product of beta-carotene hydroxylation, zeaxanthin, but not of the downstream xanthophylls, viola- and neoxanthin. Changes in endogenous gene expression were extensive and partially overlapping with those of LCY-e silenced tubers: CrtISO, LCY-b and ZEP were induced in both cases, indicating that they may respond to the balance between individual carotenoid species.

Conclusion
Together with epsilon-cyclization of lycopene, beta-carotene hydroxylation is another regulatory step in potato tuber carotenogenesis. The data are consistent with a prevalent role of CHY2, which is highly expressed in tubers, in the control of this step. Combination of different engineering strategies holds good promise for the manipulation of tuber carotenoid content.
A pragmatic randomised controlled trial of hydrotherapy and land exercises on overall well being and quality of life in rheumatoid arthritis
Authors: Eversden Lis , Maggs Fiona , Nightingale Peter , Jobanputra Paresh 
Published: March 2007

AbstractBackgroundHydrotherapy is highly valued by people with rheumatoid arthritis yet few studies have compared the benefits of exercises in heated water against exercises on land. In particular, data on quality of life is rarely reported. This is especially important because patients treated with hydrotherapy often report an enhanced sense of well-being. We report a randomised controlled trial in which we compared the effects of hydrotherapy with exercises on land on overall response to treatment, physical function and quality of life in patients with rheumatoid arthritis.MethodsOne hundred and fifteen patients with RA were randomised to receive a weekly 30-minute session of hydrotherapy or similar exercises on land for 6 weeks. Our primary outcome was a self-rated global impression of change – a measure of treatment effect on a 7-point scale ranging from 1(very much worse) to 7 (very much better) assessed immediately on completion of treatment. Secondary outcomes including EuroQol health related quality of life, EuroQol health status valuation, HAQ, 10 metre walk time and pain scores were collected at baseline, after treatment and 3 months later. Binary outcomes were analysed by Fisher's exact test and continuous variables by Wilcoxon or Mann-Whitney tests.ResultsBaseline characteristics of the two groups were comparable. Significantly more patients treated with hydrotherapy (40/46, 87%) were much better or very much better than the patients treated with land exercise (19/40, 47.5%), p < 0.001 Fisher's exact test. Eleven patients allocated land exercise failed to complete treatment compared with 4 patients allocated hydrotherapy (p = 0.09). Sensitivity analyses confirmed an advantage for hydrotherapy if we assumed non-completers would all not have responded (response rates 70% versus 38%; p < 0.001) or if we assumed that non-completers would have had the same response as completers (response rates 82% versus 55% p = 0.002). Ten metre walk time improved after treatment in both cases (median pre-treatment time for both groups combined 10.9 seconds, post-treatment 9.1 s, and 3 months later 9.6 s). There was however no difference between treatment groups. Similarly there were no significant differences between groups in terms of changes to HAQ, EQ-5D utility score, EQ VAS and pain VAS.ConclusionPatients with RA treated with hydrotherapy are more likely to report feeling much better or very much better than those treated with land exercises immediately on completion of the treatment programme. This perceived benefit was not reflected by differences between groups in 10-metre walk times, functional scores, quality of life measures and pain scores.