bluuebunny/crossref_metadata_2025 huggingface dataset:
The Synthesis and Properties of Free‐Base [14]Triphyrin(2.1.1) Compounds and the Formation of Subporphyrinoid Metal Complexes
Authors: Xue Zhao Li , Mack John , Lu Hua , Zhang Lei , You Xiao Zeng , Kuzuhara Daiki , Stillman Martin , Yamada Hiroko , Yamauchi Seigo , Kobayashi Nagao , Shen Zhen
Published: March 2011

The synthesis of [14]triphyrin(2.1.1) compounds is described. In contrast with conventional subporphyrins, which consistently contain a central boron atom, free‐base heteroaromatic compounds can be formed. A modified Lindsey method was used to prepare a range of different [14]triphyrins(2.1.1) in yields of up to 35 % based on the reaction of diethylpyrrole (1 a) and fused pyrroles of bicyclo[2.2.2]octadiene (BCOD) (2 a–e) and dihydroethanonaphthalene (4 a) with various aryl aldehydes. The concentration of BF3⋅OEt2 catalyst plays the key role in determining the yield of the [14]triphyrin(2.1.1) macrocycle relative to the conventional tetrapyrrole porphyrin product. Retro‐Diels–Alder reactions of 2 a–e and 4 a result in the formation of [14]tribenzotriphyrin (2.1.1) (3 a–e) and [14]trinaphthotriphyrin(2.1.1) (5 a). The effects of exocyclic ring annulation on the electronic structure are examined in detail based on optical spectroscopy, theoretical calculations, and electrochemical measurements. The availability of free‐base compounds enables the formation of [ReI(CO)3(triphyrin)] (6 a) and [RuII(CO)2Cl(triphyrin)] (7 a) complexes based on a modified retro‐Diels–Alder reaction. X‐ray structures are reported for 4 a and 6 a.
Cr/Ni‐Catalyzed Vinylation of Aldehydes: A Mechanistic Study on the Catalytic Roles of Nickel and Chromium
Authors: Harnying Wacharee , Kaiser André , Klein Axel , Berkessel Albrecht
Published: March 2011

The roles of nickel and chromium catalysts in the coupling reaction of vinyl halides and aldehydes, the so‐called Nozaki–Hiyama–Kishi (NHK) reaction, have been studied by UV/Vis spectroscopy, electrochemical, and spectroelectrochemical methods. Electrochemical studies revealed that nickel plays the central role in activating the vinyl halide by reductive cleavage, to form a rapidly decomposing vinyl–Ni species. The latter can, however, be stabilized in the presence of the Cr complex. The redox behavior of the Ni complexes in the presence of vinyl halide demonstrated that the vinyl halide activation results from interaction with a one‐electron reduced nickel species [formally NiI], not necessarily with a Ni0 species. It was furthermore shown by UV/Vis spectroscopy and spectroelectrochemical methods that low‐valent nickel [Ni0] results from the interaction of the NiII catalyst with CrCl2.
Design of Sinh‐Domain filters using complementary operators
Authors: Kasimis Chrisostomos , Psychalinos Costas
Published: March 2011

A new systematic method for designing Sinh‐Domain filters is introduced in this paper. This is achieved by employing an appropriate set of complementary operators, in order to transpose the conventional functional block diagram representation of each linear operation to the corresponding one into the Sinh‐Domain. The proposed method offers the benefits of facilitating the design procedure of high‐order Sinh‐Domain filters and of the absence of any restriction concerning the type and/or the order of the realized filter function. As an example, a third‐order Sinh‐Domain leapfrog filter is designed by employing the proposed set of operators. Two possible realizations are given and their performance has been evaluated and compared through simulation results. Copyright © 2011 John Wiley & Sons, Ltd.
Interleukin 32 promotes hematopoietic progenitor expansion and attenuates bone marrow cytotoxicity
Authors: Moldenhauer Anja , Futschik Matthias , Lu Huili , Helmig Melanie , Götze Patricc , Bal Gürkan , Zenke Martin , Han Wei , Salama Abdulgabar
Published: March 2011

The identification of soluble factors involved in stem cell renewal is a major goal in the assessment of the BM niche. We have previously shown that human endothelial cell (EC) supernatants can induce the proliferation of hematopoietic progenitor cells (HPCs), especially after stimulation with IL‐1β. To identify new potential growth factors, we compared the expression profile of IL‐1β‐stimulated ECs over 4, 8 and 16 h with non‐stimulated ECs using oligonucleotide microarrays covering more than 46 000 transcripts. Most significant changes were detected after 4 h. Utilization of Gene Ontology annotation for the stimulated EC transcriptome indicated multiple upregulated genes encoding extracellular proteins with a cell–cell signaling function. Using flow cytometry, delta, colony and cobblestone assays, we assessed the proliferative capacities of 11 gene products, i.e. IL‐8, IL‐32, FGF‐18, osteoprotegerin, Gro 1–3, ENA78, GCP‐2, CCL2 and CCL20, which are not known to induce HPC expansion. Notably, IL‐32 and to a lesser degree osteoprotegerin and Gro 3 significantly induced the proliferation of HPCs. Furthermore, IL‐32 attenuated chemotherapy‐related BM cytotoxicities by increasing the number of HPCs in mice. Our findings confirm that the combination of microarrays and gene annotation helps to identify new hematopoietic growth factors.
IL‐33‐activated dendritic cells are critical for allergic airway inflammation
Authors: Besnard Anne‐Gaëlle , Togbe Dieudonnée , Guillou Noëlline , Erard François , Quesniaux Valérie , Ryffel Bernhard
Published: March 2011

IL‐33, a new member of the IL‐1 family cytokine, is involved in Th2‐type responses in a wide range of diseases and signals through the ST2 receptor expressed on many immune cells. Since the effects of IL‐33 on DCs remain controversial, we investigated the ability of IL‐33 to modulate DC functions in vitro and in vivo. Here, we report that IL‐33 activates myeloid DCs to produce IL‐6, IL‐1b, TNF, CCL17 and to express high levels of CD40, CD80 OX40L and CCR7. Importantly, IL‐33‐activated DCs prime naive lymphocytes to produce the Th2 cytokines IL‐5 and IL‐13, but not IL‐4. In vivo, IL‐33 exposure induces DC recruitment and activation in the lung. Using an OVA‐induced allergic lung inflammation model, we demonstrate that the reduced airway inflammation in ST2‐deficient mice correlates with the failure in DC activation and migration to the draining LN. Finally, we show that adoptive transfer of IL‐33‐activated DCs exacerbates lung inflammation in a DC‐driven model of allergic airway inflammation. These data demonstrate for the first time that IL‐33 activates DCs during antigen presentation and thereby drives a Th2‐type response in allergic lung inflammation.
Reprogrammed quiescent B cells provide an effective cellular therapy against chronic experimental autoimmune encephalomyelitis
Authors: Calderón‐Gómez Elisabeth , Lampropoulou Vicky , Shen Ping , Neves Patricia , Roch Toralf , Stervbo Ulrik , Rutz Sascha , Kühl Anja A. , Heppner Frank L. , Loddenkemper Christoph , Anderton Stephen M. , Kanellopoulos Jean M. , Charneau Pierre , Fillatreau Simon
Published: March 2011

Activated B cells can regulate immunity and have been envisaged as a potential cell‐based therapy for treating autoimmune diseases. However, activated human B cells can also propagate immune responses, and the effects resulting from their infusion into patients cannot be predicted. This led us to consider resting B cells, which in contrast are poorly immunogenic, as an alternative cellular platform for the suppression of unwanted immunity. Here, we report that resting B cells can be directly engineered with lentiviral vectors to express antigens in a remarkably simple, rapid, and effective way. Notably, this neither required nor induced activation of the B cells. With this approach we were able to produce reprogrammed resting B cells that inhibited antigen‐specific CD4+ T cells, CD8+ T cells, and B cells upon adoptive transfer in mice. Furthermore, resting B cells engineered to ectopically express myelin oligodendrocyte glycoprotein antigen protected recipient mice from severe disability and demyelination in EAE, and even induced complete remission from disease in mice lacking functional natural Tregs, which otherwise developed chronic paralysis. In conclusion, our study introduces reprogrammed quiescent B cells as a novel tool for suppressing undesirable immunity.
Alternative activation of macrophages by IL‐4 requires SHIP degradation
Authors: Weisser Shelley B. , McLarren Keith W. , Voglmaier Nicole , van Netten‐Thomas Christina J. , Antov Andrey , Flavell Richard A. , Sly Laura M.
Published: March 2011

Alternatively activated macrophages are critical in host defense against parasites and are protective in inflammatory bowel disease, but contribute to pathology in asthma and solid tumors. The mechanisms underlying alternative activation of macrophages are only partially understood and little is known about their amenability to manipulation in pathophysiological conditions. Herein, we demonstrate that Src homology 2‐domain‐containing inositol‐5′‐phosphatase (SHIP)‐deficient murine macrophages are more sensitive to IL‐4‐mediated skewing to an alternatively activated phenotype. Moreover, SHIP levels are decreased in macrophages treated with IL‐4 and in murine GM‐CSF‐derived and tumor‐associated macrophages. Loss of SHIP and induction of alternatively activated macrophage markers, Ym1 and arginase I (argI), were dependent on phosphatidylinositol 3‐kinase (PI3K) activity and argI induction was dependent on the class IA PI3Kp110δ isoform. STAT6 was required to reduce SHIP protein levels, but reduced SHIP levels did not increase STAT6 phosphorylation. STAT6 transcription was inhibited by PI3K inhibitors and enhanced when SHIP was reduced using siRNA. Importantly, reducing SHIP levels enhanced, whereas SHIP overexpression or blocking SHIP degradation reduced, IL‐4‐induced argI activity. These findings identify SHIP and the PI3K pathway as critical regulators of alternative macrophage activation and SHIP as a target for manipulation in diseases where macrophage phenotype contributes to pathology.
Oil composition of advanced selections from an olive breeding program
Authors: León Lorenzo , Beltrán Gabriel , Aguilera Maria P. , Rallo Luis , Barranco Diego , De la Rosa Raúl
Published: March 2011

Fifteen genotypes coming from crosses between the cultivars Arbequina, Frantoio and Picual were selected on the basis of their agronomic characteristics in a breeding program initiated in 1991. In the present work, the main components of the olive oil of these 15 advances selections have been characterized and compared to their genitors. A wide range of variation was observed for all the fatty acids, minor components and related characteristics evaluated, with significant differences between genotypes for all of them except for β‐tocopherol content. These results confirm the strong genetic influence on olive oil quality previously reported on olive oil cultivar evaluations. The values obtained in the selections have extended the range of variation of their three genitors for all the characters evaluated, except for γ‐tocopherol. Selections UC‐I 7‐8, UC‐I 5‐44 and UC‐I 2‐68 showed the highest average values for tocopherols, polyphenol and C18:1 contents, respectively. Finally, multivariate analysis allowed the classification of genotypes in four groups according to their olive oil composition.

Practical applications: Olive oil composition is considered one of the most important objectives in breeding programs aiming at obtaining new olive cultivars. In the last decades olive breeding programs are being carried out in the main olive‐producing countries and several new cultivars and advanced selections have been described. The results of this work provide an initial characterization of virgin olive oils of advanced selections coming from crosses between the cultivars Arbequina, Frantoio and Picual and suggest a strong genetic influence on fatty acid composition, several minor components and related characteristics. These results, together with the agronomic characterization of these selections previously reported, will be used for the final selection of the best genotypes to be registered as new cultivars.
Developments in Chiral Binaphthyl‐Derived Brønsted/Lewis Acids and Hydrogen‐Bond‐Donor Organocatalysis
Authors: Schenker Sebastian , Zamfir Alexandru , Freund Matthias , Tsogoeva Svetlana B.
Published: March 2011

In recent years, binaphthyl compounds have found frequent applications in the design of various asymmetric organocatalysts, because binaphthyl structures are an attractive platform for organocatalyst development, particularly in light of their axial chirality characteristic. In this review, we discuss recent achievements in developing enantioselective transformations by using catalysts derived from axially chiral binaphthyls: Brønsted acids (different from BINOL‐phosphates), Lewis acids, and hydrogen‐bond donors. Results published after 2004 through 2010 are presented.
Dynamic Kinetic Resolution of β‐Amino Esters by a Heterogeneous System of a Palladium Nanocatalyst and Candida antarctica Lipase A (Eur. J. Org. Chem. 10/2011)
Authors: Engström Karin , Shakeri Mozaffar , Bäckvall Jan‐E.
Published: March 2011

The cover picture shows the dynamic kinetic resolution of β‐amino esters, where racemization catalyzed by palladium nanoparticles is combined with enantioselective resolution by Candida antarctica lipase A (CALA). β‐Amino acids and esters are essential components of many biologically active compounds. Natural products containing β‐amino acids and esters have been found to hold many interesting properties, including insecticidal, antifungal and antitumor activity. Details are discussed in the Short Communication by J.‐E. Bäckvall et al. on p. 1827 ff. Background photo by Sixten Engström.
Electrolysis‐reducing electrodes for electrokinetic devices
Authors: Erlandsson Per G. , Robinson Nathaniel D.
Published: March 2011

Direct current electrokinetic systems generally require Faradaic reactions to occur at a pair of electrodes to maintain an electric field in an electrolyte connecting them. The vast majority of such systems, e.g. electrophoretic separations (capillary electrophoresis) or electroosmotic pumps (EOPs), employ electrolysis of the solvent in these reactions. In many cases, the electrolytic products, such as H+ and OH− in the case of water, can negatively influence the chemical or biological species being transported or separated, and gaseous products such as O2 and H2 can break the electrochemical circuit in microfluidic devices. This article presents an EOP that employs the oxidation/reduction of the conjugated polymer poly(3,4‐ethylenedioxythiophene), rather than electrolysis of a solvent, to drive flow in a capillary. Devices made with poly(3,4‐ethylenedioxythiophene) electrodes are compared with devices made with Pt electrodes in terms of flow and local pH change at the electrodes. Furthermore, we demonstrate that flow is driven for applied potentials under 2 V, and the electrodes are stable for potentials of at least 100 V. Electrochemically active electrodes like those presented here minimize the disadvantage of integrated EOP in, e.g. lab‐on‐a‐chip applications, and may open new possibilities, especially for battery‐powered disposable point‐of‐care devices.
Evaluating restoration of man‐made slopes: a threshold approach balancing vegetation and rill erosion
Authors: Moreno‐de las Heras Mariano , Díaz‐Sierra Rubén , Nicolau José M. , Zavala Miguel A.
Published: March 2011

The management of reclaimed slopes derived from industrial and civil activities (e.g. surface mining and road construction) requires the development of practical stability analysis approaches that integrate the processes and mechanisms that rule the dynamics of these ubiquitous emerging ecosystems. This work describes a new modelling approach focused on stability analysis of water‐limited reclaimed slopes, where interactive relationships between rill erosion and vegetation regulate ecosystem stability. Our framework reproduces two main groups of possible trends along the temporal evolution of reclaimed slopes: successful trends, characterized by widespread vegetation development and the effective control of rill erosion processes; and gullying trends, characterized by the progressive loss of vegetation and a sharp logistic increase in erosion rates. Furthermore, this analytical approach allows the determination of threshold values for the state variables (i.e. vegetation cover and rill erosion) that drive the system's stability, facilitating the identification of critical situations that require specific human intervention (e.g. revegetation or, in very problematic cases, revegetation combined with rill network destruction) to ensure the long‐term sustainability of the restored ecosystem. The application of our threshold analysis framework in Mediterranean‐dry reclaimed slopes derived from surface coal mining (the Teruel coalfield in central‐eastern Spain) showed a good field‐based performance. Therefore, we believe that this model is a valuable contribution for the management of water‐limited reclaimed systems, including those associated with rill erosion, as it provides a tool for the evaluation of restoration success and can play an important role in decision‐making during ecosystem restoration in severely disturbed landscapes. Copyright © 2011 John Wiley & Sons, Ltd.
Kraft mill effluent survey: Progress toward best management practices for reducing effects on fish reproduction
Authors: Kovacs Tibor G , Martel Pierre H , O'Connor Brian I , Parrott Joanne L , McMaster Mark E , Van Der Kraak Glen J , MacLatchy Deborah L , van den Heuvel Michael R , Hewitt L. Mark
Published: March 2011

Pulp and paper mill effluents have been linked to effects on fish reproduction for more than 25 years. To date, the causes of these effects and remedial strategies have eluded investigators. Recent work has shown that the degree of reproductive effect caused by a mill effluent is related to the overall organic content. If verified, this could lead to breakthroughs for best management practices (BMPs). For this study, the effluents from seven kraft mills were assessed for their ability to reduce egg production in fathead minnow (Pimephales promelas) in the laboratory. At the same time, the effluents were analyzed for three parameters thought to be good indicators of organic losses: biochemical oxygen demand (BOD), methyl-substituted 2-cyclopentenones (cellulose degradation products), and a gas chromatographic (GC) profile index, which integrates the total area of the chromatographic peaks of solvent-extracted effluents using low-resolution mass spectrometry. The results showed that the degree to which the effluents reduced egg production increased with increased organic losses as characterized by BOD and the GC profile index. Therefore, these parameters could be used to guide BMPs at kraft mills according to specific targets: BOD < 20 mg/L and GC profile index equivalent to effluent with BOD of 20 mg/L. Such targets should be achievable by good in-plant control of organic losses and optimized effluent biotreatment systems. Environ. Toxicol. Chem. 2011; 30:1421–1429. © 2011 SETAC
Mechanisms of copper accumulation in isolated mantle cells of the marine clam Mesodesma mactroides
Authors: Lopes Thaís Martins , Barcarolli Indianara Fernanda , de Oliveira Camila Bento , de Souza Marta Marques , Bianchini Adalto
Published: March 2011

In vivo copper accumulation was determined in tissues (mantle, gills, digestive gland, and hemolymph) following exposure to Cu (5 µM) for up to 96 h. Mantle was the tissue that accumulated the most Cu, followed by gill, digestive gland, and hemolymph. Therefore, in vitro Cu accumulation was evaluated in isolated mantle cells exposed to 0.5, 1.0, 2.5, and 5.0 µM Cu for 1 and 3 h. After both exposure times, no change in cell viability was observed. However, a significant Cu accumulation was observed in cells exposed to 2.5 and 5.0 µM Cu. Cell exposure to 2.5 µM Cu for 1 h did not affect the ionic (Na+, K+, Ca2+, and Cl−) content of isolated mantle cells, characterizing an “ideal” noneffect concentration for the study of the involvement of different ion-transporting proteins (Na+, K+, and Cl− channels; Na+/K+2Cl− and Na+/Cl− cotransporters; Na+/Ca2+, Cl−/HCO 3−, and Na+/H+ exchangers; Na+/K+-ATPase; V-ATPase; and carbonic anhydrase) in Cu accumulation. Isolated cells were pre-exposed (30 min) to specific blockers or inhibitors of the ion-transporting proteins and then exposed (1 h) to Cu (2.5 µM) in the presence of the drug. A significant increase of 29.1 and 24.3% in Cu accumulation was observed after cell incubation with acetozalamide (carbonic anhydrase inhibitor) and NPPB (Cl− channels blocker), respectively. On the other hand, a significant decrease (48.2%) in Cu accumulation was observed after incubation with furosemide (Na+/K+/2Cl− blocker). Taken together, these findings indicate the mantle as an important route of Cu entry in M. mactroides, pointing to the cotransporter Na+/K+/2Cl− as a major mechanism of Cu accumulation in mantle cells of the clam. Environ. Toxicol. Chem. 2011; 30:1586–1592. © 2011 SETAC
Effect of copper on ion content in isolated mantle cells of the marine clam Mesodesma mactroides
Authors: Lopes Thaís Martins , Barcarolli Indianara Fernanda , de Oliveira Camila Bento , de Souza Marta Marques , Bianchini Adalto
Published: March 2011

The effect of copper on ion content (Na+, K+, Ca2+, and Cl−) was evaluated in isolated mantle gills of the marine clam Mesodesma mactroides. Clams were collected at the Mar Grosso Beach (São José do Norte, Rio Grande do Sul [RS], southern Brazil), cryoanesthetized, and had their mantles dissected. Mantle cells were isolated and incubated in a calcium-free phosphate solution without (control) or with Cu (CuCl2). Cells were exposed to Cu for 1 h (5 µM) or 3 h (2.5 and 5 µM). In cells incubated with 2.5 µM Cu, a significant decrease in intracellular Cl− content was observed. However, in cells incubated with 5.0 µM Cu, significant reductions in Na+, K+, and Cl− intracellular content were observed. Given the mechanisms involved in ion transport in mantle cells of the marine clam M. mactroides, the findings described here suggest that Cu exposure inhibits carbonic anhydrase and Na+/K+-ATPase activity. Also, it can be suggested that Cu is competing with Na+ for the same mechanisms of ion transport in the cell membrane, such as the Na+ channels and the Na+/K+/2Cl− cotransporter. Results from the present study also clearly indicate that processes involved in cellular anion regulation are more sensitive to Cu exposure than those associated with the cellular cation regulation. Characterization of sites for Cu accumulation and toxicity in aquatic animals is important for derivation of metal binding constants at the biotic ligand. Also, identification of the mechanism of metal toxicity is needed for modeling metal accumulation in the biotic ligand and its consequent toxicity. Therefore, the findings reported here are extremely valuable for the development of a biotic ligand model version for marine and estuarine waters. Environ. Toxicol. Chem. 2011; 30:1582–1585. © 2011 SETAC
Teratogenic effects of injected methylmercury on avian embryos
Authors: Heinz Gary H , Hoffman David J , Klimstra Jon D , Stebbins Katherine R , Kondrad Shannon L , Erwin Carol A
Published: March 2011

Controlled laboratory studies with game farm mallards (Anas platyrhynchos) and chickens (Gallus gallus) have demonstrated that methylmercury can cause teratogenic effects in birds, but studies with wild species of birds are lacking. To address this need, doses of methylmercury chloride were injected into the eggs of 25 species of birds, and the dead embryos and hatched chicks were examined for external deformities. When data for controls were summed across all 25 species tested and across all types of deformities, 24 individuals out of a total of 1,533 (a rate of 1.57%) exhibited at least one deformity. In contrast, when data for all of the mercury treatments and all 25 species were summed, 188 deformed individuals out of a total of 2,292 (8.20%) were found. Some deformities, such as lordosis and scoliosis (twisting of the spine), misshapen heads, shortening or twisting of the neck, and deformities of the wings, were seldom observed in controls but occurred in much greater frequency in Hg-treated individuals. Only 0.59% of individual control dead embryos and hatchlings exhibited multiple deformities versus 3.18% for Hg-dosed dead embryos and hatchlings. Methylmercury seems to have a widespread teratogenic potential across many species of birds. Environ. Toxicol. Chem. 2011; 30:1593–1598. © 2011 SETAC
The influence of sediment particle size and organic carbon on toxicity of copper to benthic invertebrates in oxic/suboxic surface sediments
Authors: Strom David , Simpson Stuart L , Batley Graeme E , Jolley Dianne F
Published: March 2011

The use of sediment quality guidelines to predict the toxicity of metals in sediments is limited by an inadequate understanding of exposure pathways and by poor causal links between exposure and effects. For a 10-d exposure to Cu-spiked sediments, toxicity to the amphipod Melita plumulosa was demonstrated to occur through a combination of dissolved and dietary Cu exposure pathways, but for the bivalves Spisula trigonella and Tellina deltoidalis, toxicity occurred primarily by exposure to dissolved Cu. For relatively oxidized sediments that had moderate amounts of organic carbon (2.6–8.3% OC), silt (20–100% <63-µm particles) but low acid-volatile sulfide (AVS), acute toxicity thresholds for the three species were derived based on the OC-normalized Cu concentration of the less than 63-µm sediment fraction. For all three species, no effects were observed at concentrations below 10 µg/L dissolved Cu (in pore water and overlying water) or below 12 mg Cu/g OC (for <63 µm sediment). For sediments with silt/OC properties of 20/0.5, 50/1, or 70/4%, the particulate Cu-based threshold equated to 60, 120, or 480 mg Cu/kg, respectively. For oxic/suboxic sediments in which AVS is not limiting metal availability, sediment quality guidelines of this form will provide adequate protection against toxicity and improve the prediction of effects for sediments with varying properties. Environ. Toxicol. Chem. 2011; 30:1599–1610. © 2011 SETAC
An initial probabilistic hazard assessment of oil dispersants approved by the united states national contingency plan
Authors: Berninger Jason P , Williams E. Spencer , Brooks Bryan W
Published: March 2011

Dispersants are commonly applied during oil spill mitigation efforts; however, these industrial chemicals may present risks to aquatic organisms individually and when mixed with oil. Fourteen dispersants are listed on the U.S. Environmental Protection Agency (U.S. EPA) National Oil and Hazardous Substances Pollution Contingency Plan (NCP). Availability of environmental effects information for such agents is limited, and individual components of dispersants are largely proprietary. Probabilistic hazard assessment approaches including Chemical Toxicity Distributions (CTDs) may be useful as an initial step toward prioritizing environmental hazards from the use of dispersants. In the present study, we applied the CTD approach to two acute toxicity datasets: NCP (the contingency plan dataset) and DHOS (a subset of NCP listed dispersants reevaluated subsequent to the Deepwater Horizon oil spill). These datasets contained median lethal concentration (LC50) values for dispersants alone and dispersant:oil mixtures, in two standard marine test species, Menidia beryllina and Mysidopsis bahia. These CTDs suggest that dispersants alone are generally less toxic than oil. In contrast, most dispersant:oil mixtures are more toxic than oil alone. For the two datasets (treated separately because of differing methodologies), CTDs would predict 95% of dispersant:oil mixtures to have acute toxicity values above 0.32 and 0.76 mg/L for Mysidopsis and 0.33 mg/L and 1.06 mg/L for Menidia (for DHOS and NCP, respectively). These findings demonstrate the utility of CTDs as a means to evaluate the comparative ecotoxicity of dispersants alone and in mixture with different oil types. The approaches presented here also provide valuable tools for prioritizing prospective and retrospective environmental assessments of oil dispersants. Environ. Toxicol. Chem. 2011; 30:1704–1708. © 2011 SETAC
Common and distinct neural regions for the guidance of selection by visuoverbal information held in memory: Converging evidence from fMRI and rTMS
Authors: Soto David , Rotshtein Pia , Hodsoll John , Mevorach Carmel , Humphreys Glyn W.
Published: March 2011

Recent research indicates that working memory (WM) and attention interact, with attention automatically biased to stimuli that match the contents of WM. Though there is behavioral evidence for verbal guidance (written words) as well as guidance by more visual cues in WM, we have limited understanding of how these two representational formats influence the guidance of visual selection at a neural level. Here, we present converging evidence from functional MRI and transcranial magnetic stimulation (TMS), which indicates that both common and distinct neural regions mediate the influence of visuoverbal representations on WM. Colored shapes, but not words, in WM activated the superior frontal gyrus (SFG) and recognition memory areas in the temporal lobe when the contents of WM matched a stimulus in a subsequent search display. rTMS to the SFG disrupted WM effects from colored shapes. The lateral occipital cortex, however, tended to be more activated with written word cues, and rTMS to the lateral occipital complex tended to disrupt effects from written words more than from colored shapes in WM. There was also evidence for cue validity effects from colored shapes and written stimuli operating through different subthalamic nuclei. We discuss the evidence for understanding the neural systems mediating attention effects from WM. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Activation in parietal operculum parallels motor recovery in stroke
Authors: Forss Nina , Mustanoja Satu , Roiha Kristina , Kirveskari Erika , Mäkelä Jyrki P. , Salonen Oili , Tatlisumak Turgut , Kaste Markku
Published: March 2011

Motor recovery after stroke requires continuous interaction of motor and somatosensory systems. Integration of somatosensory feedback with motor programs is needed for the automatic adjustment of the speed, range, and strength of the movement. We recorded somatosensory evoked fields (SEFs) to tactile finger stimulation with whole‐scalp magnetoencephalography in 23 acute stroke patients at 1 week, 1 month, and 3 months after stroke to investigate how deficits in the somatosensory cortical network affect motor recovery. SEFs were generated in the contralateral primary somatosensory cortex (SI) and in the bilateral parietal opercula (PO) in controls and patients. In the patients, SI amplitude or latency did not correlate with any of the functional outcome measures used. In contrast, the contralateral PO (cPO) amplitude to the affected hand stimuli correlated significantly with hand function in the acute phase and during recovery; the weaker the PO activation, the clumsier the hand was. At 1 and 3 months, enhancement of the cPO activation paralleled the improvement of the hand function. Whole‐scalp magnetoencephalography measurements revealed that dysfunction of somatosensory cortical areas distant from the ischemic lesion may affect the motor recovery. Activation strength of the PO paralleled motor recovery after stroke, suggesting that the PO area is an important hub in mediating modulatory afferent input to motor cortex. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Neural processing of social rejection: The role of schizotypal personality traits
Authors: Premkumar Preethi , Ettinger Ulrich , Inchley‐Mort Sophie , Sumich Alexander , Williams Steven C.R. , Kuipers Elizabeth , Kumari Veena
Published: March 2011

A fear of being rejected can cause perceptions of more insecurity and stress in close relationships. Healthy individuals activate the dorsal anterior cingulate cortex (dACC) when experiencing social rejection, while those who are vulnerable to depression deactivate the dACC presumably to downregulate salience of rejection cues and minimize distress. Schizotypal individuals, characterized by unusual perceptual experiences and/or odd beliefs, are more rejection sensitive than normal. We tested the hypothesis, for the first time, that individuals with high schizotypy also have an altered dACC response to rejection stimuli. Twenty‐six healthy individuals, 14 with low schizotypy (LS) and 12 with high schizotypy (HS), viewed depictions of rejection and acceptance and neutral scenes while undergoing functional MRI. Activation maps in LS and HS groups during each image type were compared using SPM5, and their relation to participant mood and subjective ratings of the images was examined. During rejection relative to neutral scenes, LS activated and HS deactivated the bilateral dACC, right superior frontal gyrus, and left ventral prefrontal cortex. Across both groups, a temporo‐occipito‐parieto‐cerebellar network was active during rejection, and a left fronto‐parietal network during acceptance, relative to neutral scenes, and the bilateral lingual gyrus during rejection relative to acceptance scenes. Our finding of dACC‐dorso‐ventral PFC activation in LS, but deactivation in HS individuals when perceiving social rejection scenes suggests that HS individuals attach less salience to and distance themselves from such stimuli. This may enable them to cope with their higher‐than‐normal sensitivity to rejection. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Orientation‐selective functional magnetic resonance imaging adaptation in primary visual cortex revisited
Authors: Weigelt Sarah , Limbach Katharina , Singer Wolf , Kohler Axel
Published: March 2011

The processing of orientations is at the core of our visual experience. Orientation selectivity in human visual cortex has been inferred from psychophysical experiments and more recently demonstrated with functional magnetic resonance imaging (fMRI). One method to identify orientation‐selective responses is fMRI adaptation, in which two stimuli—either with the same or with different orientations—are presented successively. A region containing orientation‐selective neurons should demonstrate an adapted response to the “same orientation” condition in contrast to the “different orientation” condition. So far, human primary visual cortex (V1) showed orientation‐selective fMRI adaptation only in experimental designs using prolonged pre‐adaptation periods (∼40 s) in combination with top‐up stimuli that are thought to maintain the adapted level. This finding has led to the notion that orientation‐selective short‐term adaptation in V1 (but not V2 or V3) cannot be demonstrated using fMRI. The present study aimed at re‐evaluating this question by testing three differently timed adaptation designs. With the use of a more sensitive analysis technique, we show robust orientation‐selective fMRI adaptation in V1 evoked by a short‐term adaptation design. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Movement related cortical potentials of cued versus self‐initiated movements: Double dissociated modulation by dorsal premotor cortex versus supplementary motor area rTMS
Authors: Lu Ming‐Kuei , Arai Noritoshi , Tsai Chon‐Haw , Ziemann Ulf
Published: March 2011

The dorsal premotor cortex (PMd) is thought to play a significant role in movement preparation cued by sensory information rather than in self‐initiated movements. The evidence in humans for this contention is still circumstantial. Here we explored the effects of modulation of PMd by excitability decreasing 1 Hz repetitive transcranial magnetic stimulation (rTMS) versus excitability increasing 5 Hz rTMS on two forms of movement related cortical potentials: contingent negative variation (CNV) versus Bereitschaftspotential (BP) reflecting externally cued versus self‐triggered movement preparation. Ten healthy right‐handed subjects performed visually cued or self‐triggered simple sequential finger movements with their right hand. CNV and BP were recorded by 25 EEG electrodes covering the fronto‐centro‐parietal cortex and divided into an early (1500–500 ms before a go‐signal or movement onset) and a late potential (500–0 ms). MRI‐navigated 1 Hz rTMS of the left PMd resulted in significant increase of the late CNV over the left central region predominantly contralateral to the prepared right hand movement, while 5 Hz rTMS had no effect on CNV. In contrast, 1 and 5 Hz rTMS did not modify BP. Control experiments of 1 Hz rTMS of the supplementary motor area (SMA) and of low‐intensity 1 Hz rTMS of the left primary motor cortex did not change CNV, but 1 Hz SMA‐rTMS increased late BP. This double dissociation of effects of PMd‐rTMS versus SMA‐rTMS on CNV versus BP provides direct evidence that the left PMd in humans is more involved in preparatory processes of externally cued rather than self‐initiated movements, contrasting with an opposite role of the SMA. Hum Brain Mapp 2012. © 2011 Wiley Periodicals, Inc.
Tracking emotional valence: The role of the orbitofrontal cortex
Authors: Goodkind Madeleine S. , Sollberger Marc , Gyurak Anett , Rosen Howard J. , Rankin Katherine P. , Miller Bruce , Levenson Robert
Published: March 2011

Successful navigation of the social world requires the ability to recognize and track emotions as they unfold and change dynamically. Neuroimaging and neurological studies of emotion recognition have primarily focused on the ability to identify the emotion shown in static photographs of facial expressions, showing correlations with the amygdala as well as temporal and frontal brain regions. In this study, we examined the neural correlates of continuously tracking dynamically changing emotions. Fifty‐nine patients with diverse neurodegenerative diseases used a rating dial to track continuously how positive or how negative the character in a film clip felt. Tracking accuracy was determined by comparing participants' ratings with the ratings of 10 normal control participants. The relationship between tracking accuracy and regional brain tissue content was examined using voxel‐based morphometry. Low tracking accuracy was primarily associated with gray matter loss in the right lateral orbitofrontal cortex (OFC). Our finding that the right OFC is critical to the ability to track dynamically changing emotions is consistent with previous research showing right OFC involvement in both socioemotional understanding and modifying responding in changing situations. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Gender differences in brain functional connectivity density
Authors: Tomasi Dardo , Volkow Nora D.
Published: March 2011

The neural bases of gender differences in emotional, cognitive, and socials behaviors are largely unknown. Here, magnetic resonance imaging data from 336 women and 225 men revealed a gender dimorphism in the functional organization of the brain. Consistently across five research sites, women had 14% higher local functional connectivity density (lFCD) and up to 5% higher gray matter density than men in cortical and subcortical regions. The negative power scaling of the lFCD was steeper for men than for women, suggesting that the balance between strongly and weakly connected nodes in the brain is different across genders. The more distributed organization of the male brain than that of the female brain could help explain the gender differences in cognitive style and behaviors and in the prevalence of neuropsychiatric diseases (i.e., autism spectrum disorder). Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Hemispheric specialization during mental imagery of brisk walking
Authors: Crémers Julien , Dessoullières Aurélie , Garraux Gaëtan
Published: March 2011

Objectives:

Brisk walking, a sensitive test to evaluate gait capacity in normal and pathological aging such as parkinsonism, is used as an alternative to classical fitness program for motor rehabilitation and may help to decrease the risk of cognitive deterioration observed with aging. In this study, we aimed to identify brain areas normally involved in its control.

Methods:

We conducted a block‐design blood oxygen level dependent function magnetic resonance imaging (BOLD fMRI) experiment in 18 young healthy individuals trained to imagine themselves in three main situations: brisk walking in a 25‐m‐long corridor, standing or lying. Imagined walking time (IWT) was measured as a control of behavioral performance during fMRI.

Results:

The group mean IWT was not significantly different from the actual walking time measured during a training session prior to the fMRI study. Compared with other experimental conditions, mental imagery (MI) of brisk walking was associated with stronger activity in frontal and parietal regions mainly on the right, and cerebellar hemispheres, mainly on the left. Presumed imagined walking speed (2.3 ± 0.4 m/s) was positively correlated with activity levels in the right dorsolateral prefrontal cortex and posterior parietal lobule along with the vermis and the left cerebellar hemisphere.

Interpretations:

A new finding in this study is that MI of brisk walking in young healthy individuals strongly involves processes lateralized in right fronto‐parietal regions along with left cerebellum. These results show that brisk walking might be a non automatic locomotor activity requiring a high‐level supraspinal control. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Delayed-onset caspase-dependent massive hepatocyte apoptosis upon fas activation in bak/bax-deficient mice
Authors: Hikita Hayato , Takehara Tetsuo , Kodama Takahiro , Shimizu Satoshi , Shigekawa Minoru , Hosui Atsushi , Miyagi Takuya , Tatsumi Tomohide , Ishida Hisashi , Li Wei , Kanto Tatsuya , Hiramatsu Naoki , Shimizu Shigeomi , Tsujimoto Yoshihide , Hayashi Norio
Published: March 2011

Abstract:

The proapoptotic Bcl-2 family proteins Bak and Bax serve as an essential gateway to the mitochondrial pathway of apoptosis. When activated by BH3-only proteins, Bak/Bax triggers mitochondrial outer membrane permeabilization leading to release of cytochrome c followed by activation of initiator and then effector caspases to dismantle the cells. Hepatocytes are generally considered to be type II cells because, upon Fas stimulation, they are reported to require the BH3-only protein Bid to undergo apoptosis. However, the significance of Bak and Bax in the liver is unclear. To address this issue, we generated hepatocyte-specific Bak/Bax double knockout mice and administered Jo2 agonistic anti-Fas antibody or recombinant Fas ligand to them. Fas-induced rapid fulminant hepatocyte apoptosis was partially ameliorated in Bak knockout mice but not in Bax knockout mice, and was completely abolished in double knockout mice 3 hours after Jo2 injection. Importantly, at 6 hours, double knockout mice displayed severe liver injury associated with repression of XIAP, activation of caspase-3/7 and oligonucleosomal DNA breaks in the liver, without evidence of mitochondrial disruption or cytochrome c–dependent caspase-9 activation. This liver injury was not ameliorated in a cyclophilin D knockout background nor by administration of necrostatin-1, but was completely inhibited by administration of a caspase inhibitor after Bid cleavage. Conclusion: Whereas either Bak or Bax is critically required for rapid execution of Fas-mediated massive apoptosis in the liver, delayed onset of mitochondria-independent, caspase-dependent apoptosis develops even in the absence of both. The present study unveils an extrinsic pathway of apoptosis, like that in type I cells, which serves as a backup system even in type II cells. (HEPATOLOGY 2011 )
Ethnic differences in viral dominance patterns in patients with hepatitis B virus and hepatitis C virus dual infection
Authors: Nguyen Long H. , Ko Steve , Wong Shane S. , Tran Pelu S. , Trinh Huy N. , Garcia Ruel T. , Ahmed Aijaz , Lutchman Glen A. , Keeffe Emmet B. , Nguyen Mindie H.
Published: March 2011

Studies of hepatitis B virus (HBV)/hepatitis C virus (HCV) dual infection are limited. Most are small, conducted outside the United States, and compare dual infection with HCV monoinfection. The goal of this study was to characterize HBV/HCV dual infection in a large multiethnic, matched, case-control study of dual-infected and HBV-monoinfected patients at two United States centers. Using an International Classification of Disease Version 9 electronic query and chart review, we identified 115 HBV/HCV dual-infected patients with serial HBV DNA, HCV RNA, and alanine aminotransferase (ALT) levels. As a control, 115 HBV-monoinfected patients were chosen randomly and matched with cases by age ±10 years, sex, Asian versus non-Asian ethnicity, and study site. Both groups had similar sex, ethnic, and age distributions (68% male, 83% Asian, age 52 ± 14 years). The median follow-up times were 33 and 38 months for the dual-infected and monoinfected groups, respectively. More monoinfected patients received HBV antiviral therapy than dual-infected patients (43% versus 24%; P = 0.002). No significant difference was detected between the proportion of monoinfected versus dual-infected patients with ALT above 40 U/L at presentation or during follow-up. Dual infection patients exhibited very little HBV/HCV codominance at baseline and throughout follow-up: patients had either HBV viremia with low or absent HCV RNA or detectable HCV RNA with low or absent HBV DNA. Asian ethnicity was predictive of HBV dominance after adjusting for sex, age, and baseline ALT elevation (odds ratio 7.35; P = 0.01). Conclusion: HBV/HCV dual-infected and HBV-monoinfected patients had similar clinical characteristics. Asian ethnicity is a major independent predictor of HBV-dominant disease, and HCV dominance with undetectable HBV DNA is more common in non-Asian individuals. Larger studies are needed to further characterize the natural history of HBV/HCV dual infection in Asian and non-Asian individuals. (HEPATOLOGY 2011;)
The contributions of human resource development research across disciplines: A citation and content analysis
Authors: Jeung Chang‐Wook , Yoon Hea Jun , Park Sunyoung , Jo Sung Jun
Published: March 2011

The primary purpose of the current study is to identify how human resource development (HRD) research has contributed to the knowledge base across social science disciplines during the past two decades. We identified the top 20 Academy of Human Resource Development (AHRD) journal articles that have been most frequently cited in research articles published in journals other than the four AHRD journals. With the use of content analysis of the most‐cited articles, three key research themes were identified: (a) training transfer and evaluation, (b) learning in organizations, and (c) knowledge sharing and knowledge creation. The research contributions of HRD within the field of HRD and across disciplines are discussed.