bluuebunny/crossref_metadata_2025_split huggingface dataset:
PBDE developmental effects on embryonic zebrafish
Authors: Usenko Crystal Y , Robinson Eleanor M , Usenko Sascha , Brooks Bryan W , Bruce Erica D 
Published: May 2011

Abstract
Polybrominated diphenyl ethers (PBDEs) have become ubiquitous environmental contaminants with potential for bioaccumulation and maternal-fetal transfer that has led to regulatory bans and/or phasing out of several technical mixtures of PBDEs. In the present study, six PBDE congeners (BDE 28, BDE 47, BDE 99, BDE 100, BDE 153, BDE 183) were evaluated for developmental effects on embryonic zebrafish. These congeners were chosen because they are environmentally relevant and cover a wide range of physical-chemical properties. Alterations in behavior, physical malformations, and mortality were scored daily until 168 h postfertilization (hpf). A concentration-dependent increase in spontaneous movement indicated an early onset of behavioral responses to PBDE exposures. Spontaneous movement was affected the most by BDE 47 and BDE 28, whereas BDE 183 did not alter behavior at any concentration tested. Swimming rates were significantly increased by BDE 28 at 96 and 120 hpf, but decreased swimming activity at 168 hpf. Additionally, BDE 47 significantly decreased the swimming rate at 168 hpf. Other endpoints included malformations and mortality. Congeners with fewer bromines (BDE 28, 47, 99, and 100) also induced a curved body axis starting around 120 hpf, which was followed by mortality. BDEs 153 and 183, however, did not elicit these adverse effects. A relationship was found between log KOW and median lethal concentration (LC50) and median effective concentration (EC50). Structure–activity relationships in this study suggest that PBDE acute toxicity results from a receptor-mediated effect and further studies are necessary to determine these pathways. Environ. Toxicol. Chem. 2011; 30:1865–1872. © 2011 SETAC
Effects of predator cues on pesticide toxicity: Toward an understanding of the mechanism of the interaction
Authors: Qin Guangqiu , Presley Steven M , Anderson Todd A , Gao Weimin , Maul Jonathan D 
Published: May 2011

Abstract
Pesticide toxicity may be modified by a number of co-occurring environmental and ecological stressors. Coexposure to predator cues has been shown to potentiate and/or synergize toxicity of pesticides. However, the mechanisms behind these interactions are not well understood. Here we examine the effects of fish predator (bluegill, Lepomis macrochirus) cues on toxicity of five different pesticides to the freshwater cladoceran, Ceriodaphnia dubia. The purpose for examining patterns among pesticides was to test the idea that the mechanism of the interaction could be explained by a general stress response; that is, the interaction patterns would be similar regardless of the pesticide's mechanism of action [MOA]). Acute 96-h concentration–response experiments were conducted for pesticides with and without fish cues. Predator cues influenced the toxicity of pesticides and the interaction patterns varied among pesticides. Fipronil exhibited a synergistic interaction, while predator cues interacted antagonistically for bifenthrin and thiacloprid. Other compounds previously reported to potentiate toxicity (malathion) were found to act additively. The results demonstrate that factors such as pesticide bioavailability, KOC, and exposure concentration may be important for predicting the occurrence of these interactions and that patterns were not consistent among pesticides varying in MOA. Predator stress is an important component for structuring communities and ecosystem processes. Fully understanding how this process may interact with organic contaminants may best be achieved by examination at toxicokinetic and toxicodynamic scales. Environ. Toxicol. Chem. 2011; 30:1926–1934. © 2011 SETAC
Hedging under model misspecification: All risk factors are equal, but some are more equal than others …
Authors: Branger Nicole , Krautheim Eva , Schlag Christian , Seeger Norman 
Published: May 2011

AbstractIt is often difficult to distinguish among different option pricing models that consider stochastic volatility and/or jumps based on a cross‐section of European option prices. This can result in model misspecification. We analyze the hedging error induced by model misspecification and show that it can be economically significant in the cases of a delta hedge, a minimum‐variance hedge, and a delta‐vega hedge. Furthermore, we explain the surprisingly good performance of a simple ad‐hoc Black‐Scholes hedge. We compare realized hedging errors (an incorrect hedge model is applied) and anticipated hedging errors (the hedge model is the true one) and find that there are substantial differences between the two distributions, particularly depending on whether stochastic volatility is included in the hedge model. Therefore, hedging errors can be useful for identifying model misspecification. Furthermore, model risk has severe implications for risk measurement and can lead to a significant misestimation, specifically underestimation, of the risk to which a hedged position is exposed. © 2011 Wiley Periodicals, Inc. Jrl Fut Mark
Independent component analysis of DTI reveals multivariate microstructural correlations of white matter in the human brain
Authors: Li Yi‐Ou , Yang Fanpei G. , Nguyen Christopher T. , Cooper Shelly R. , LaHue Sara C. , Venugopal Sandya , Mukherjee Pratik 
Published: May 2011

AbstractIt has recently been demonstrated that specific patterns of correlation exist in diffusion tensor imaging (DTI) parameters across white matter tracts in the normal human brain. These microstructural correlations are thought to reflect phylogenetic and functional similarities between different axonal fiber pathways. However, this earlier work was limited in three major respects: (1) the analysis was restricted to only a dozen selected tracts; (2) the DTI measurements were averaged across whole tracts, whereas metrics such as fractional anisotropy (FA) are known to vary considerably within single tracts; and (3) a univariate measure of correlation was used. In this investigation, we perform an automated multivariate whole‐brain voxel‐based study of white matter FA correlations using independent component analysis (ICA) of tract‐based spatial statistics computed from 3T DTI in 53 healthy adult volunteers. The resulting spatial maps of the independent components show voxels for which the FA values within each map co‐vary across individuals. The strongest FA correlations were found in anatomically recognizable tracts and tract segments, either singly or in homologous pairs. Hence, ICA of DTI provides an automated unsupervised decomposition of the normal human brain into multiple separable microstructurally correlated white matter regions, many of which correspond to anatomically familiar classes of white matter pathways. Further research is needed to determine whether whole‐brain ICA of DTI represents a novel alternative to tractography for feature extraction in studying the normal microstructure of human white matter as well as the abnormal white matter microstructure found in neurological and psychiatric disorders. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.
Power spectrum scale invariance identifies prefrontal dysregulation in paranoid schizophrenia
Authors: Radulescu Anca R. , Rubin Denis , Strey Helmut H. , Mujica‐Parodi Lilianne R. 
Published: May 2011

AbstractTheory and experimental evidence suggest that complex living systems function close to the boundary of chaos, with erroneous organization to an improper dynamical range (too stiff or chaotic) underlying system‐wide dysregulation and disease. We hypothesized that erroneous organization might therefore also characterize paranoid schizophrenia, via optimization abnormalities in the prefrontal‐limbic circuit regulating emotion. To test this, we acquired fMRI scans from 35 subjects (N= 9 patients with paranoid schizophrenia andN= 26 healthy controls), while they viewed affect‐valent stimuli. To quantify dynamic regulation, we analyzed the power spectrum scale invariance (PSSI) of fMRI time‐courses and computed the geometry of time‐delay (Poincaré) maps, a measure of variability. Patients and controls showed distinct PSSI in two clusters (k1:Z= 4.3215,P= 0.00002 andk2:Z= 3.9441,P= 0.00008), localized to the orbitofrontal/medial prefrontal cortex (Brodmann Area 10), represented by β close to white noise in patients (β ≈ 0) and in the pink noise range in controls (β ≈ −1). Interpreting the meaning of PSSI differences, the Poincaré maps indicated less variability in patients than controls (Z= −1.9437,P= 0.05 fork1;Z= −2.5099,P= 0.01 fork2). That the dynamics identified Brodmann Area 10 is consistent with previous schizophrenia research, which implicates this area in deficits of working memory, executive functioning, emotional regulation and underlying biological abnormalities in synaptic (glutamatergic) transmission. Our results additionally cohere with a large body of work finding pink noise to be the normal range of central function at the synaptic, cellular, and small network levels, and suggest that patients show less supple responsivity of this region. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.
New quinoline‐2, ‐3, and 4‐yl‐(amino) methylphosphonates: Synthesis and study on the CP bond cleavage in quinoline‐2 and ‐4 derivatives under acidic conditions
Authors: Michalska Joanna , Boduszek Bogdan , Olszewski Tomasz K. 
Published: May 2011

AbstractSynthesis of new quinoline‐(amino)methylphosphonic acids, their phosphonate esters, and phosphine oxides is presented. The desired new compounds were efficiently obtained by nucleophilic addition of phosphorous species to quinoline‐derived Schiff bases. In addition, it was discovered that heating of quinolin‐2 and quinolin‐4‐yl‐(amino)‐methylphosphonates with aqueous HCl leads to their decomposition resulting in a rupture of the CP bond, rejecting of the phosphorus containing fragment, and formation of the corresponding secondary quinoline‐2 and quinoline‐4‐alkylamines. Two alternative mechanistic pathways for this cleavage are postulated. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:617–624, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20704
WEIGHT‐LOSS DIETING BEHAVIOR: AN ECONOMIC ANALYSIS
Authors: Rosin Odelia 
Published: May 2011

SUMMARYIn light of the widespread phenomena of diet failure and excessive dieting, this paper presents a theoretical economic analysis of the decision‐making process of weight‐loss dieting. The paper incorporates behavioral elements involved in the process of dieting: effort exerted in dieting, influence of social norms concerning body weight, time‐inconsistent present biased preferences, and a distinction between naiveté and sophistication. The model explains cyclic dieting and provides interesting insights on the extent of weight‐loss dieting. The extent of dieting is an increasing function of initial body weight and a decreasing function of the effort exerted in dieting and the strength of social norms concerning ideal weight. Income and diet strictness have an ambiguous effect. In addition, greater dieting efforts are not necessarily balanced against a slowdown in body metabolism or a higher initial body weight. Copyright © 2011 John Wiley & Sons, Ltd.
Dicitrinol, a Citrinin Dimer, Produced by Penicillium janthinellum
Authors: do Rosário Marinho Andrey M. , Rodrigues‐Fo. Edson 
Published: May 2011

AbstractA citrinin dimer, named dicitrinol (3), was isolated from extracts obtained from a rice cultivation of Penicillium janthinellum, a fungus found in fruits of Melia azedarach. Dicitrinol (3) was isolated by classical chromatographic procedures, and identified by MS, and 1D‐ and 2D‐NMR data. A biosynthetic scheme is proposed for this new dimerization of citrinin. Dicitrinol (3) was shown to be slightly weaker than citrinin regarding bacterial inhibition.
Diterpenoid Alkaloids from Delphinium tatsienense
Authors: Chen Feng‐Zheng , Chen Qiao‐Hong , Liu Xiao‐Yu , Wang Feng‐Peng 
Published: May 2011

AbstractThree new C20‐diterpenoid alkaloids, along with twenty‐two known alkaloids, were isolated from the whole herbs of Delphinium tatsienense. The new alkaloids include a vakognavine‐type C20‐diterpenoid alkaloid, designated as tatsienenseine A (1), and two hetisine‐type C20‐diterpenoid alkaloids, designated as tatsienenseines B (2) and C (3). Their structures were elucidated by IR, HR‐ESI‐MS, 1D‐ and 2D‐NMR analyses.
Fully automated pipeline for quantification and localization of white matter hyperintensity in brain magnetic resonance image
Authors: Jeon Seun , Yoon Uicheul , Park Jun‐Sung , Seo Sang Won , Kim Jung‐Hyun , Kim Sung Tae , Kim Sun I. , Na Duk L. , Lee Jong‐Min 
Published: May 2011

AbstractAutomated white matter hyperintensity (WMH) segmentation on magnetic resonance imaging is greatly advantageous for various clinical studies using large‐sample data. Accurate localization of WMH can provide more beneficial information for clinical studies, as differences of regional WMH existence may be linked to clinical symptoms. We suggest a fully automated method for WMH quantification and localization without human interaction using T1‐weighted and fluid‐attenuated inversion‐recovery (FLAIR) images. The known sources of false‐positive results in the subarachnoid space and brain‐cerebrospinal fluid (CSF) interface were removed by applying a WMH candidate‐region mask. WMH segmentation was performed based on the Markov random field model. The intensity‐substitution method was developed for the accurate localization of WMH, with proper tissue classification and nonlinear registration. The performance of the method was evaluated via comparison with manual delineation; the similarity index and the overlap ratio were 89.94 and 81.90, respectively. © 2011 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 21, 193–200, 2011
Decoding the nonstationary neural activity in motor cortex for brain machine interfaces
Authors: Zhang Shaomin , Liao Yuxi , Zheng Xiaoxiang , Chen Weidong , Wang Yiwen 
Published: May 2011

AbstractPrevious decoding algorithms used in brain machine interfaces (BMIs) usually seek a static functional mapping between the spatio‐temporal neural activity and behavior and assume that the neural spike statistics do not change over time. However, recent work indicates the significant variance in neural activities, which suggests the nonfeasibility of the stationary assumptions on the neural signal sequences. To track the time‐changing neural activity during the nonlinear decoding process, we developed a time‐varying approach based on general regression neural network (GRNN) with a dynamic pattern layer. Applied on both simulated neural activity and in vivo BMI data extracted from rat's motor cortex, the proposed method reconstructs the movement signals better than the original GRNN algorithm with static pattern layer, which raises the promise of successfully tracking the time‐varying neural activity for BMIs decoding. © 2011 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 21, 158–164, 2011
Subject and class specific frequency bands selection for multiclass motor imagery classification
Authors: Suk Heung‐Il , Lee Seong‐Whan 
Published: May 2011

AbstractEEG‐based discrimination among motor imagery states has been widely studied for brain‐computer interfaces (BCIs) due to the great potential for real‐life applications. However, in terms of designing a motor imagery‐based BCI system, a lot of research in the literature either uses a frequency band of interest selected manually based on the visual analysis of EEG data or is set to a general broad band, causing performance degradation in classification. In this article, we propose a novel method of selecting subject and class specific frequency bands based on the analysis of a channel‐frequency matrix, which we call a channel‐frequency map. We operate the classification process for each frequency band individually, i.e., spatial filtering, feature extraction, and classification, and determine a class label for an input EEG by considering the outputs from multiple classifiers together at the end. From our experiments on a public dataset of BCI Competition IV (2008) II‐a that includes four motor imagery tasks from nine subjects, the proposed algorithm outperformed the common spatial pattern (CSP) algorithm in a broad band and a filter bank CSP algorithm on average in terms of cross‐validation and session‐to‐session transfer rate. Furthermore, a considerable increase of classification accuracy has been achieved for certain subjects. We also would like to note that the proposed data‐driven frequency bands selection method is applicable to other kinds of single‐trial EEG classifications that are based on modulations of brain rhythms, by no means limited to motor imagery‐based BCI applications. © 2011 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 21, 123–130, 2011
Large sample group independent component analysis of functional magnetic resonance imaging using anatomical atlas‐based reduction and bootstrapped clustering
Authors: Anderson Ariana , Bramen Jennifer , Douglas Pamela K. , Lenartowicz Agatha , Cho Andrew , Culbertson Chris , Brody Arthur L. , Yuille Alan L. , Cohen Mark S. 
Published: May 2011

AbstractIndependent component analysis (ICA) is a popular method for the analysis of functional magnetic resonance imaging (fMRI) signals that is capable of revealing connected brain systems of functional significance. To be computationally tractable, estimating the independent components (ICs) inevitably requires one or more dimension reduction steps. Whereas most algorithms perform such reductions in the time domain, the input data are much more extensive in the spatial domain, and there is broad consensus that the brain obeys rules of localization of function into regions that are smaller in number than the number of voxels in a brain image. These functional units apparently reorganize dynamically into networks under different task conditions. Here we develop a new approach to ICA, producing group results by bagging and clustering over hundreds of pooled single‐subject ICA results that have been projected to a lower‐dimensional subspace. Averages of anatomically based regions are used to compress the single subject‐ICA results prior to clustering and resampling via bagging. The computational advantages of this approach make it possible to perform group‐level analyses on datasets consisting of hundreds of scan sessions by combining the results of within‐subject analysis, while retaining the theoretical advantage of mimicking what is known of the functional organization of the brain. The result is a compact set of spatial activity patterns that are common and stable across scan sessions and across individuals. Such representations may be used in the context of statistical pattern recognition supporting real‐time state classification. © 2011 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 21, 223–231, 2011
A review of studies on androgen and estrogen exposure in fish early life stages: effects on gene and hormonal control of sexual differentiation
Authors: Leet Jessica K. , Gall Heather E. , Sepúlveda Maria S. 
Published: May 2011

ABSTRACTTeleost fish are unique among vertebrates in that phenotypic sex or onset of sex inversion can be easily manipulated by hormonal treatments. In recent years, researchers have begun reporting concentrations of synthetic and natural hormones in the environment. Although concentrations are very low (in the parts per trillion to low parts per billion), they are still of concern because of the high potency of synthetic hormones and the enhanced susceptibility of teleost fishes, especially early life stages, to hormonal exposures. In this review, we will focus on sex differentiation in teleost fishes and how these processes in fish early life stages may be impacted by environmental hormones which are known to contaminate aquatic environments. We will start by reviewing information on sources and concentrations of hormones in the environment and continue by summarizing the state of knowledge of sex differentiation in teleost gonochoristic fishes, including information on genes involved (e.g. cyp19, dmrt1, sox9 and foxl2). We will end our review with a summary of studies that have examined the effects of androgens and estrogens on fish sex differentiation after exposure of fish embryos and larvae and with ideas for future research. Copyright © 2011 John Wiley & Sons, Ltd.
AMP‐activated protein kinase inhibits TGF‐β‐induced fibrogenic responses of hepatic stellate cells by targeting transcriptional coactivator p300
Authors: Lim Joong‐Yeon , Oh Min‐A , Kim Won Ho , Sohn Hee‐Young , Park Sang Ick 
Published: May 2011

AbstractLiver fibrosis is a common consequence of various chronic liver injuries, including virus infection and ethanol. Activated hepatic stellate cells (HSCs) contribute to liver fibrosis through the accumulation of extracellular matrix proteins, including type I alpha collagen (COL1A). The activation of adenosine monophosphate‐activated protein kinase (AMPK) modulates HSCs activation, but its underlying mechanism remains unclear. Here, we report that AMPK inhibits transforming growth factor (TGF)‐β‐induced fibrogenic property of HSCs by regulating transcriptional coactivator p300. We treated human (LX‐2) and rat (CFSC‐2G) HSC lines with TGF‐β to induce fibrogenic activation of HSCs. Pharmacological activation of AMPK by treatment with 5‐aminoimidazole‐4‐carboxamide‐1‐beta‐4‐ribofuranoside (AICAR), metformin, or adiponectin lowered TGF‐β‐induced expression of COL1A and myofibroblast marker alpha‐smooth muscle actin (α‐SMA). Transient transduction of constitutively active AMPKα (caAMPKα) was sufficient to attenuate COL1A and α‐SMA expression, whereas an AMPK inhibitor considerably abrogated the inhibitory effect of AICAR on fibrogenic gene expression. Although AMPK significantly suppressed Smad‐dependent transcription, it did not affect TGF‐β‐stimulated phosphorylation, nuclear localization, or DNA‐binding activity of Smad2/3. AICAR rather attenuated TGF‐β‐induced Smad3 interaction with transcriptional coactivator p300 accompanying with reduction of Smad3 acetylation. Moreover, AICAR induced not only physical interaction between AMPK and p300 but also proteasomal degradation of p300 protein. Our data provide substantial evidence that AMPK could be a novel therapeutic target for treatment of liver fibrosis, by demonstrating the underlying mechanism of AMPK‐induced antifibrotic function in HSCs. J. Cell. Physiol. 227: 1081–1089, 2012. © 2011 Wiley Periodicals, Inc.
Tensile force inhibits the proliferation of human periodontal ligament fibroblasts through Ras‐p38 MAPK up‐regulation
Authors: Kook Sung‐Ho , Lee Jeong‐Chae 
Published: May 2011

AbstractThe capacity of human periodontal ligament fibroblasts (PLF) to proliferate in response to mechanical force plays a critical role in orthodontic tooth movement. Extensive research has not fully revealed the mechanisms by which the PLF respond to mechanical force. The responses to force differ according to the origin of cells and the type of stress applied. In this study, we examined the proliferative response of PLF to tensile force. We also explored cellular mechanisms involved in the mechanosignal transduction of tensile force. Application to the force to PLF with 1.5% elongation for 1 h inhibited cell proliferation. This was accompanied by reductions in several cyclins and cyclin‐dependent kinases (CDKs) involved in the G1/S transition; however, p21 knockdown prevented these events. Pharmacological inhibitor of p38 MAPK suppressed the force‐mediated growth inhibition as well as the decrease in p21 expression. Ras inhibitor almost completely blocked the tension‐mediated increases in p‐p38 MAPK and p‐p21, and the attendant increase in PLF proliferation. These findings suggest that tension force activates Ras‐p38 MAPK pathways in PLF, which up‐regulate p21 and arrest cell cycle progression at the G1phase. J. Cell. Physiol. 227: 1098–1106, 2012. © 2011 Wiley Periodicals, Inc.