bluuebunny/crossref_metadata_2025_split huggingface dataset:
The neuronal nicotinic α4β2 receptor has a high maximal probability of being open
Authors: Li Ping , Steinbach Joe H 
Published: March 2010

Background and purpose: A fundamental property of transmitter‐gated ion channels is the probability a channel will be open (Popen) when stimulated by a concentration of agonist that elicits a maximal response. This value is critical for interpreting steady‐state concentration–response relationships in terms of channel activation, and for understanding the actions of drugs that potentiate responses. We used analysis of non‐stationary noise to estimate the maximal probability the nicotinic α4β2 receptor is open.Experimental approach: HEK293 cells stably transfected to express human α4β2 nicotinic receptors were studied using whole‐cell voltage clamp. Nicotinic agonists (acetylcholine, nicotine, cytisine and 5‐iodo A‐85380) were applied, and the relationship between variance of the elicited whole‐cell current and mean current was analysed.Key results: The variance did not increase linearly with the mean current. For acetylcholine and nicotine the relationship between variance and mean indicates that the maximalPopenis greater than 0.8. The number of agonist‐activatable channels was estimated to be about 1000 per cell. The mean single channel conductance at −60 mV was indistinguishable when currents were elicited by acetylcholine (18 pS), nicotine (17 pS) or 5‐iodo A‐85380 (17 pS), whereas the value for cytisine was larger (24 pS).Conclusions and implications: The neuronal nicotinic α4β2 receptor has a maximal probability of being open that is greater than 0.8. This conclusion applies to the receptor containing three α4 and two β2 subunits (the low‐sensitivity stoichiometry), but may not apply to the receptor containing two α4 and three β2 subunits (the high‐sensitivity stoichiometry).This article is commented on by Papke, pp. 1903–1905 of this issue. To view this commentary visithttp://dx.doi.org/10.1111/j.1476‐5381.2010.00868.x
Celecoxib treatment restores pharmacosensitivity in a rat model of pharmacoresistant epilepsy
Authors: Schlichtiger J , Pekcec A , Bartmann H , Winter P , Fuest C , Soerensen J , Potschka H 
Published: March 2010

Background and purpose: A functional link between seizure‐induced P‐glycoprotein overexpression at the blood–brain barrier and therapeutic failure has been suggested by several studies using rodent epilepsy models and human epileptic tissue. Recently, we reported that interference with the mechanisms that up‐regulate P‐glycoprotein in response to seizure activity might provide a novel approach to control its expression in the epileptic brain. Based on these data, we hypothesized that blocking the appropriate signalling cascade by cyclooxygenase‐2 inhibition should improve brain penetration of antiepileptic drugs and help to overcome drug resistance.Experimental approach: Effects of the selective cyclooxygenase‐2 inhibitor celecoxib on the response to the P‐glycoprotein substrate, phenobarbital, was evaluated in a chronic model of drug‐resistant temporal lobe epilepsy in rats. Drug‐resistant rats selected from this model exhibit a marked overexpression of P‐glycoprotein in the hippocampus and other limbic brain regions.Key results: Responders and non‐responders were selected from a group of rats with spontaneous recurrent seizures after prolonged treatment with phenobarbital at maximum tolerated doses. The efficacy of phenobarbital was re‐evaluated following a 6 day treatment with celecoxib and the frequency of spontaneous recurrent seizures was significantly reduced in both groups of rats, phenobarbital responders or non‐responders selected from the previous drug trial.Conclusions and implications: Pretreatment with the cyclooxygenase‐2 inhibitor restored the anticonvulsant activity of phenobarbital in rats that failed to exhibit a relevant response before celecoxib treatment. Our data provide further support for a novel therapeutic approach to overcome transporter‐mediated drug resistance in epilepsies.
Disability and Incident Coronary Heart Disease in Older Community‐Dwelling Adults: The Three‐City Study
Authors: Plichart Matthieu , Barberger‐Gateau Pascale , Tzourio Christophe , Amouyel Philippe , Pérès Karine , Ritchie Karen , Jouven Xavier , Ducimetière Pierre , Empana Jean‐Philippe 
Published: March 2010

OBJECTIVES: To prospectively assess the association between disability and incident fatal and nonfatal coronary heart disease (CHD) in older adults free of cardiovascular disease (CVD).DESIGN: A French multicenter prospective population‐based cohort of 9,294 subjects, aged 65 and older at baseline, recruited between 1999 and 2001 and followed for 6 years.SETTING: Three cities in France: Bordeaux in the southwest, Dijon in the northeast, and Montpellier in the southeast.PARTICIPANTS: Seven thousand three hundred fifty‐four participants with no history of CVD and with available information on disability status. Subjects were categorized at baseline as having no disability, mild disability (mobility only), and moderate or severe disability (mobility plus activities of daily living or instrumental activities of daily living).MEASUREMENTS: Incident fatal and nonfatal coronary events (angina pectoris, myocardial infarction, revascularization procedures, and CHD death).RESULTS: At baseline, the mean level of the risk factors increased gradually with the severity of disability. After a median follow‐up of 5.2 years, 264 first coronary events, including 55 fatal events, occurred. After adjustment for cardiovascular risk factors, participants with moderate or severe disability had a 1.7 times (95% confidence interval (CI)=1.0–2.7) greater risk of overall CHD than nondisabled subjects, whereas those with mild disability were not at greater CHD risk. An association was also found with fatal CHD, for which the risk increased gradually with the severity of disability (hazard ratio (HR)mild disability=1.7, 95% CI=0.8–3.6; HRmoderate/severe disability=3.5, 95% CI=1.3–9.3; P for trend=.01).CONCLUSION: In older community‐dwelling adults, the association between disability and incident CHD is mostly due to an association with fatal CHD.
Variation in Prostate‐Specific Antigen Screening in Men Aged 80 and Older in Fee‐for‐Service Medicare
Authors: Bynum Julie , Song Yunjie , Fisher Elliott 
Published: March 2010

OBJECTIVES: To determine the rate of prostate‐specific antigen (PSA) screening in men aged 80 and older in Medicare and to examine geographic variation in screening rates across the U.S.DESIGN: Retrospective cohort study of variation across hospital referral regions using administrative data.SETTING: National random sample in fee‐for‐service Medicare.PARTICIPANTS: Medicare beneficiaries aged 80 and older in 2003.MEASUREMENTS: Percentage of men aged 80 and older screened using the PSA test.RESULTS: The national rate of PSA screening in men aged 80 and older was 17.2%, but there was wide variation across regions (<2–38%). Higher PSA screening in a region was positively associated with greater total costs (correlation coefficient (r)=0.49, P<.001), greater intensive care unit use at the end of life (r=0.46, P<.001), and greater number of unique physicians seen (r=0.36, P<.001). PSA screening was negatively associated with proportion of beneficiaries using a primary care physician as opposed to a medical subspecialist for the predominance of ambulatory care (r=−0.38, P<.001).CONCLUSION: PSA screening in men aged 80 and older is common practice, although its frequency is highly variable across the United States. Its association with fragmented physician care and aggressive end‐of‐life care may reflect less reliance on primary care and consequent difficulty informing patients of the potential harms and low likelihood of benefit of this procedure.
Delirium: An Independent Predictor of Functional Decline After Cardiac Surgery
Authors: Rudolph James L. , Inouye Sharon K. , Jones Richard N. , Yang Frances M. , Fong Tamara G. , Levkoff Sue E. , Marcantonio Edward R. 
Published: March 2010

OBJECTIVES: To determine whether patients who developed delirium after cardiac surgery were at risk of functional decline.DESIGN: Prospective cohort study.SETTING: Two academic hospitals and a Veterans Affairs Medical Center.PARTICIPANTS: One hundred ninety patients aged 60 and older undergoing elective or urgent cardiac surgery.MEASUREMENTS: Delirium was assessed daily and was diagnosed according to the Confusion Assessment Method. Before surgery and 1 and 12 months postoperatively, patients were assessed for function using the instrumental activities of daily living (IADL) scale. Functional decline was defined as a decrease in ability to perform one IADL at follow‐up.RESULTS: Delirium occurred in 43.1% (n=82) of the patients (mean age 73.7±6.7). Functional decline occurred in 36.3% (n=65/179) at 1 month and in 14.6% (n=26/178) at 12 months. Delirium was associated with greater risk of functional decline at 1 month (relative risk (RR)=1.9, 95% confidence interval (CI)=1.3–2.8) and tended toward greater risk at 12 months (RR=1.9, 95% CI=0.9–3.8). After adjustment for age, cognition, comorbidity, and baseline function, delirium remained significantly associated with functional decline at 1 month (adjusted RR=1.8, 95% CI=1.2–2.6) but not at 12 months (adjusted RR=1.5, 95% CI=0.6–3.3).CONCLUSION: Delirium was independently associated with functional decline at 1 month and had a trend toward association at 12 months. These findings provide justification for intervention trials to evaluate whether delirium prevention or treatment strategies might improve postoperative functional recovery.
Prevalence and 10‐Year Outcomes of Frailty in Older Adults in Relation to Deficit Accumulation
Authors: Song Xiaowei , Mitnitski Arnold , Rockwood Kenneth 
Published: March 2010

OBJECTIVES: To evaluate the prevalence and 10‐year outcomes of frailty in older adults in relation to deficit accumulation.DESIGN: Prospective cohort study.SETTING: The National Population Health Survey of Canada, with frailty estimated at baseline (1994/95) and mortality follow‐up to 2004/05.PARTICIPANTS: Community‐dwelling older adults (N=2,740, 60.8% women) aged 65 to 102 from 10 Canadian provinces. During the 10‐year follow‐up, 1,208 died.MEASUREMENTS: Self‐reported health information was used to construct a frailty index (Frailty Index) as a proportion of deficits accumulated in individuals. The main outcome measure was mortality.RESULTS: The prevalence of frailty increased with age in men and women (correlation coefficient=0.955–0.994, P<.001). The Frailty Index estimated that 622 (22.7%, 95% confidence interval (CI)=21.0–24.4%) of the sample was frail. Frailty was more common in women (25.3%, 95% CI=23.2–27.5%) than in men (18.6%, 95% CI=15.9–21.3%). For those aged 85 and older, the Frailty Index identified 39.1% (95% CI=31.3–46.9%) of men as frail, compared with 45.1% (95% CI=39.7–50.5%) of women. Frailty significantly increased the risk of death, with an age‐ and sex‐adjusted hazard ratio for the Frailty Index of 1.57 (95% CI=1.41–1.74).CONCLUSION: The prevalence of frailty increases with age and at any age lessens survival. The Frailty Index approach readily identifies frail people at risk of death, presumably because of its use of multiple health deficits in multidimensional domains.
The New Economic Sociology of Prices: An Analysis Inspired by the Austrian School of Economics
Authors: Fillieule Renaud 
Published: March 2010

AbstractThe new economic sociology includes some reference studies on the sociology of prices. They have not until now been studied by economists, and this article attempts to fill that gap by offering a detailed analysis, inspired by the Austrian School of Economics, of their object and approach. We first show that, from a theoretical point of view, the explanations advanced by these sociologists are based implicitly on basic models of economics, such as the “law of supply and demand” and the “law of costs,” and that they cannot therefore replace economic explanations of prices. Secondly, from a methodological point of view, these studies are based on field surveys that provide concrete information on certain markets but they lose sight of an aspect that is fundamental to the Austrian School, the interdependence of prices in different markets. And when this interdependence is taken into account, namely, in the case of the relationship between cost and price, the causal link postulated by sociologists goes from cost to price when Austrian economists argue that it goes in the opposite direction.
From W. N. Hohfeld to J. R. Commons, and Beyond? A “Law and Economics” Enquiry on Jural Relations
Authors: Vatiero Massimiliano 
Published: March 2010

AbstractIn this article we try to reformulate the approaches of Wesley Newcomb Hohfeld and John Rogers Commons on jural relations speculating on the concept of positionality as introduced by Fred Hirsch in his original work on positional good and competition. Furthermore, by placing Hohfeld's jural lowest common denominator within the Commonsian transaction, we propose a more structured economic description of the jural relations theory.
Acting up or acting out? Unlocking children's talk in literature circles
Authors: Pearson Caroline 
Published: March 2010

AbstractIt is generally accepted that talk enriches children's interpretations of texts in literature circle discussions. However, the nature of that talk and exactly how it facilitates interpretation of texts has not been much analysed. This article describes some work undertaken with a class of Scottish children, aged 9–10, to introduce them to the idea of literature circles. The literature circle discussions were then recorded and analysed. The purpose of the project was to record the kinds of exchanges, chains of comment and range of discourses and voices that children used when talking among themselves, and to reflect on their function and value. It was found that a lot of the talk was exploratory though not always in the sense proposed by Mercer. In his terms much was ‘cumulative’. Some talk veered towards anecdotal chat. The children also frequently put on voices not their own, mimicking characters in the story they were reading, and other people they knew. These forms of talk are not always encouraged in the classroom, their effectiveness for learning being in doubt. This article argues that cumulative talk, the telling of anecdotes and the performing of different characters' voices all have a useful function in discussions of books: they can encourage engagement, be helpful in bringing texts to life and advance children's thinking about literature.
Collapse of a molecular cloud core to stellar densities: the radiative impact of stellar core formation on the circumstellar disc
Authors: Bate Matthew R. 
Published: March 2010

Abstract
We present results from the first three-dimensional radiation hydrodynamical calculations to follow the collapse of a molecular cloud core beyond the formation of the stellar core. We find that the energy released by the formation of the stellar core, within the optically thick first hydrostatic core, is comparable to the binding energy of the disc-like first core. This heats the inner regions of the disc, drives a shock wave through the disc, dramatically decreases the accretion rate on to the stellar core and launches a temporary bipolar outflow perpendicular to the rotation axis that travels in excess of 50 au into the infalling envelope.
This outburst may assist the young protostar in launching a conventional magnetic jet. Furthermore, if these events are cyclic, they may provide a mechanism for intense bursts of accretion separated by long periods of relatively quiescent accretion which can potentially solve both the protostellar luminosity problem and the apparent age spread of stars in young clusters. Such outbursts may also provide a formation mechanism for the chondrules found in meteorites, with the outflow transporting them to large distances in the circumstellar disc.
Monitoring the response of canine hyperadrenocorticism to trilostane treatment by assessment of acute phase protein concentrations
Authors: Arteaga A. , Dhand N. K. , McCann T. , Knottenbelt C. M. , Tebb A. J. , Evans H. , Eckersall P. David , Ramsey I. K. 
Published: March 2010

Background: Acute phase proteins (APPS) include haptoglobin (Hp), C‐reactive protein (CRP) and serum amyloid A (SAA). Increased Hp concentrations may be induced by endogenous or exogenous glucocorticoids in dogs.Objectives: To assess whether control of hyperadrenocorticism (HAC) affects the concentrations of Hp, CRP, SAA, alkaline phosphatase (ALKP) and cholesterol, to determine whether these analytes can be used to assess control of HAC following trilostane treatment, and whether a combination of these tests offers a valid method of assessing disease control.Methods: Hp, CRP, SAA, ALKP and cholesterol were assessed in 11 dogs with spontaneous HAC before and after treatment with trilostane. Adequate control of HAC was defined as post‐ACTH cortisol less than 150 nmol/l.Results: Significant reductions in Hp, ALKP, cholesterol and SAA (P<0·05) but not of CRP were found after control of HAC. Only Hp, cholesterol and ALKP were moderately informative (Se& Sp>0·7) of disease control when compared to adrenocorticotropin or corticotropin (ACTH) stimulation test. SAA and CRP were unhelpful (Se & Sp<0·7). The analysis of the combination of the analytes did not improve the correlation with ACTH stimulation test.ClinicalRelevance: Relying on these analytes does not provide additional information over ACTH stimulation test results when assessing control of HAC treated with trilostane.
Disproportional effects in populations of concern for pandemic influenza: insights from seasonal epidemics in Wisconsin, 1967–2004
Authors: Lofgren Eric T. , Wenger Julia B. , Fefferman Nina H. , Bina David , Gradus Steve , Bhattacharyya Sanjib , Naumov Yuri N. , Gorski Jack , Naumova Elena N. 
Published: March 2010

Please cite this paper as: Lofgren et al. (2010) Disproportional effects in populations of concern for pandemic influenza: insights from seasonal epidemics in Wisconsin, 1967–2004. Influenza and Other Respiratory Viruses 4(4), 205–212.Background  Influenza infections pose a serious burden of illness in the United States. We explored age, influenza strains, and seasonal epidemic curves in relation to influenza‐associated mortality.Methods  The state of Wisconsin death records for the years 1967–2004 were analyzed for three distinct populations: children, general population, and elderly. Yearly parameters of duration, intensity, and peak timing were obtained from Annual Harmonic Regression coefficients.Results  Overall, elderly had the highest rate and intensity of influenza mortality. The children and infant subpopulations showed an earlier and wider range in duration of peak timing than elderly. During A/Hong Kong/1/68 pandemic years, the elderly subpopulation showed no change in mortality rates while a sharp increase was observed for the children and infant subpopulations. In epidemic years such as 1966–1969, children and infants showed a dramatic decrease in the severity of influenza outbreaks over time. The elderly had increased baseline mortality in years (1986–1987) where predominant strain was characterized as A/Singapore/6/86.Conclusions  Our findings indicate that the younger populations may have benefited from the lack of a major shift in viral strains for a number of decades. Furthermore, we demonstrate considerable heterogeneity in the spread of seasonal influenza across age categories, with implications both for the modeling of influenza seasonality, risk assessment, and effective distribution and timing of vaccine and prophylactic interventions.
Impacting the Science Attitudes of Minority High School Youth
Authors: Ellis Ronald S. 
Published: March 2010

AbstractA study involving urban, minority high school students in a supplemental education program was conducted during 1989 to test the null hypothesis that no relationship exists between exposure to program activities and changes in mathematics performance or attitude towards science. The treatment activities integrated science, with language arts, mathematics, computers and counseling and enabled students to discuss matters of concern and the relationship of these concerns to their academic work and to future success in careers based in science and mathematics. Mathematics performance data were analyzed using ANOVA (premath X group, postmath X group), and t‐test/pairs (premath vs. postmath). Pre‐ and postreatment data on attitude towards science were rank ordered, paired and analyzed using the Wilcoxin Matched‐Pairs Signed Ranks Test.The findings reveal a significantly positive treatment effect. In spite of the caution suggested by the limited sample, exposure to the treatment has resulted in an increased positive effect, not only upon attitude towards science, but also upon mathematics performance.
Corporate Diversification, Relatedness, and Firm Value: Evidence from Korean Firms*
Authors: Bae Sung C. , Kwon Taek Ho , Lee Jang Woo 
Published: March 2010

AbstractWe examine the valuation effects of diversification activities for Korean firms by diversification type and the occasion of the Korean financial crisis. Employing a unique dataset of 2,894 firm‐years for the entire manufacturing industries, we find that diversification by Korean firms on average decreases firm value but its effect varies by the type of diversification. While unrelated diversification erodes firm value, related diversification is associated with a non‐negative effect on firm value. These valuation effects are more pronounced before the crisis than after the crisis. Our results also show an important role of a firm's affiliation to a large business group, known as chaebols, that related diversification by chaebol‐affiliated firms comes with a significant value gain. We further find that the different valuation effects of unrelated and related diversification are closely related to a firm's ownership concentration and financial leverage. Our results are robust to different samples and regression model specifications.
Volatility, Market Structure, and the Bid‐Ask Spread*
Authors: Chung Kee H. , Kim Youngsoo 
Published: March 2010

AbstractWe test the conjecture that the specialist system on the New York Stock Exchange (NYSE) provides better liquidity services than the NASDAQ dealer market in times of high return volatility when adverse selection and inventory risks are high. We motivate our conjecture from the observation that there is a designated specialist for each stock on the NYSE who is directly responsible for maintaining a reasonable level of liquidity (i.e., the bid‐ask spread) as the ‘liquidity provider of last resort’ whereas there is no such designated dealer on NASDAQ. Empirical evidence is consistent with our conjecture. In a similar vein, we show that the specialist system provides better liquidity than the dealer market in thin markets.
Option Pricing with Extreme Events: Using Câmara and Heston(2008)‘s Model*
Authors: Kim Sol 
Published: March 2010

AbstractFor the KOSPI 200 Index options, we examine the effect of extreme events for pricing options. We compare Black and Scholes (1973) model with Câmara and Heston (2008)'s options pricing model that allows for both big downward and upward jumps. It is found that Câmara and Heston (2008)'s extreme events option pricing model shows better performance than Black and Scholes (1973) model does for both in‐sample and out‐of‐sample pricing. Also downward jumps are a more important factor for pricing stock index options than upward jumps. It is consistent with the empirical evidence that reports the sneers or negative skews in the stock index options market.