bluuebunny/crossref_metadata_2025_split huggingface dataset:
Social information influences trust behaviour in adolescents
Authors: Lee Nikki C. , Jolles Jelle , Krabbendam Lydia 
Published: November 2015

ABSTRACTTrust plays an integral role in daily interactions within adolescents' social environment. Using a trust game paradigm, this study investigated the modulating influence of social information about three interaction partners on trust behaviour in adolescents aged 12–18 (N = 845). After receiving information about their interaction partners prior to the task, participants were most likely to share with a 'good' partner and rate this partner as most trustworthy. Over the course of the task all interaction partners showed similar levels of trustworthy behaviour, but overall participants continued to trust and view the good partner as more trustworthy than 'bad' and 'neutral' partners throughout the game. However, with age the ability to overcome prior social information and adapt trust behaviour improved: middle and late adolescents showed a larger decrease in trust of the good partner than early adolescents, and late adolescents were more likely to reward trustworthy behaviour from the negative partner.
Influence of amyloid and APOE on cognitive performance in a late middle‐aged cohort
Authors: Mielke Michelle M. , Machulda Mary M. , Hagen Clinton E. , Christianson Teresa J. , Roberts Rosebud O. , Knopman David S. , Vemuri Prashanthi , Lowe Val J. , Kremers Walter K. , Jack Clifford R. , Petersen Ronald C. 
Published: November 2015

AbstractIntroductionFew studies have examined the effects of amyloid and apolipoprotein E (APOE) genotype on cognition among middle‐aged individuals.MethodsWe included 464 cognitively normal, test‐naïve, participants with Pittsburgh compound B positron emission tomography amyloid imaging, mean age of 62.7 (range, 51–71 years), enrolled in the Mayo Clinic Study of Aging. Participants completed multiple cognitive assessments, including a standard neuropsychological battery and the CogState computerized battery, over 30 months of follow‐up. Linear mixed models were used to examine the effects of amyloid and APOE genotype on baseline cognition and cognitive decline.ResultsElevated amyloid was not associated with tests of episodic memory but did predict declines on tests of executive function. APOE genotype was not associated with cognition. Among APOE ɛ4 noncarriers, higher amyloid was predictive of decline on tests of executive function and on one episodic memory test.DiscussionElevated amyloidosis and APOE genotype do not appear to exert a dramatic influence on cognition in middle age.
Importance of home study visit capacity in dementia studies
Authors: Crane Paul K. , Gibbons Laura E. , McCurry Susan M. , McCormick Wayne , Bowen James D. , Sonnen Joshua , Keene C. Dirk , Grabowski Thomas , Montine Thomas J. , Larson Eric B. 
Published: November 2015

AbstractIntroductionThe importance of home research study visit capacity in Alzheimer's disease (AD) studies is unknown.MethodsAll evaluations are from the prospective Adult Changes in Thought study. Based on analyses of factors associated with volunteering for a new in‐clinic initiative, we analyzed AD risk factors and the relevance of neuropathologic findings for dementia comparing all data including home visits, and in‐clinic data only. We performed bootstrapping to determine whether differences were greater than expected by chance.ResultsOf the 1781 people enrolled during 1994–1996 with ≥1 follow‐up, 1369 (77%) had in‐clinic data, covering 61% of follow‐up time. In‐clinic data resulted in excluding 76% of incident dementia and AD cases. AD risk factors and the relevance of neuropathologic findings for dementia were both different with in‐clinic data.DiscussionLimiting data collection in AD studies to research clinics alone likely reduces power and also can lead to erroneous inferences.
Platelet-derived CXCL12 regulates monocyte function, survival, differentiation into macrophages and foam cells through differential involvement of CXCR4–CXCR7
Authors: Chatterjee M , von Ungern-Sternberg S N I , Seizer P , Schlegel F , Büttcher M , Sindhu N A , Müller S , Mack A , Gawaz M 
Published: November 2015

AbstractPlatelets store and release CXCL12 (SDF-1), which governs differentiation of hematopoietic progenitors into either endothelial or macrophage-foam cells. CXCL12 ligates CXCR4 and CXCR7 and regulates monocyte/macrophage functions. This study deciphers the relative contribution of CXCR4–CXCR7 in mediating the effects of platelet-derived CXCL12 on monocyte function, survival, and differentiation. CXCL12 and macrophage migration inhibitory factor (MIF) that ligate CXCR4–CXCR7 induced a dynamic bidirectional trafficking of the receptors, causing CXCR4 internalization and CXCR7 externalization during chemotaxis, thereby influencing relative receptor availability, unlike MCP-1. In vivo we found enhanced accumulation of platelets and platelet-macrophage co-aggregates in peritoneal fluid following induction of peritonitis in mice. The relative surface expression of CXCL12, CXCR4, and CXCR7 among infiltrated monocytes was also enhanced as compared with peripheral blood. Platelet-derived CXCL12 from collagen-adherent platelets and recombinant CXCL12 induced monocyte chemotaxis specifically through CXCR4 engagement. Adhesion of monocytes to immobilized CXCL12 and CXCL12-enriched activated platelet surface under static and dynamic arterial flow conditions were mediated primarily through CXCR7 and were counter-regulated by neutralizing platelet-derived CXCL12. Monocytes and culture-derived-M1–M2 macrophages phagocytosed platelets, with the phagocytic potential of culture-derived-M1 macrophages higher than M2 involving CXCR4–CXCR7 participation. CXCR7 was the primary receptor in promoting monocyte survival as exerted by platelet-derived CXCL12 against BH3-mimetic induced apoptosis (phosphatidylserine exposure, caspase-3 activation, loss of mitochondrial transmembrane potential). In co-culture experiments with platelets, monocytes predominantly differentiated into CD163+ macrophages, which was attenuated upon CXCL12 neutralization and CXCR4/CXCR7 blocking antibodies. Moreover, OxLDL uptake by platelets induced platelet apoptosis, like other platelet agonists TRAP and collagen-related peptide (CRP). CXCL12 facilitated phagocytosis of apoptotic platelets by monocytes and M1–M2 macrophages, also promoted their differentiation into foam cells via CXCR4 and CXCR7. Thus, platelet-derived CXCL12 could regulate monocyte-macrophage functions through differential engagement of CXCR4 and CXCR7, indicating an important role in inflammation at site of platelet accumulation.
SOX4 contributes to the progression of cervical cancer and the resistance to the chemotherapeutic drug through ABCG2
Authors: Sun R , Jiang B , Qi H , Zhang X , Yang J , Duan J , Li Y , Li G 
Published: November 2015

AbstractSOX4, a member of the SOX (sex-determining region Y-related HMG box) transcription factor family, has been reported to be abnormally expressed in a wide variety of cancers, and to exert a pleiotropic function. However, its function in progression of cervical cancer (CC) remains unknown. In this study, we found that SOX4 was highly expressed in CC cells and tissues, and overexpression of SOX4 in CC CaSki cells enhanced tumor clone formation and cell proliferation, and accelerated cell cycle progress. Meanwhile, downregulation of SOX4 by shRNA in CaSki cells inhibited cell proliferation, and slowed cell cycle progress, indicating that SOX4 contributes to the development of CC. In addition, SOX4 overexpression by gene transfer reduced the sensitivity of CaSki cells in response to the chemotherapeutic drug cisplatin, and SOX4 downregulation by RNA interference increased the sensitivity of CaSki cells in response to cisplatin. Moreover, SOX4 overexpression upregulated multiple drug resistant gene ABCG2, and SOX4 downregulation inhibited ABCG2 expression. Taken together, these results suggested that SOX4 functions to modulate cancer proliferation by regulation of cell cycle, and inhibit cancer cell sensitivity to therapeutic drug via upregulation of ABCG2. Thus, SOX4 may be a target for CC chemotherapy.
Histone H1-mediated epigenetic regulation controls germline stem cell self-renewal by modulating H4K16 acetylation
Authors: Sun Jin , Wei Hui-Min , Xu Jiang , Chang Jian-Feng , Yang Zhihao , Ren Xingjie , Lv Wen-Wen , Liu Lu-Ping , Pan Li-Xia , Wang Xia , Qiao Huan-Huan , Zhu Bing , Ji Jun-Yuan , Yan Dong , Xie Ting , Sun Fang-Lin , Ni Jian-Quan 
Published: November 2015

AbstractEpigenetics plays critical roles in controlling stem cell self-renewal and differentiation. Histone H1 is one of the most critical chromatin regulators, but its role in adult stem cell regulation remains unclear. Here we report that H1 is intrinsically required in the regulation of germline stem cells (GSCs) in the Drosophila ovary. The loss of H1 from GSCs causes their premature differentiation through activation of the key GSC differentiation factor bam. Interestingly, the acetylated H4 lysine 16 (H4K16ac) is selectively augmented in the H1-depleted GSCs. Furthermore, overexpression of mof reduces H1 association on chromatin. In contrast, the knocking down of mof significantly rescues the GSC loss phenotype. Taken together, these results suggest that H1 functions intrinsically to promote GSC self-renewal by antagonizing MOF function. Since H1 and H4K16 acetylation are highly conserved from fly to human, the findings from this study might be applicable to stem cells in other systems.
Two-dimensional membrane as elastic shell with proof on the folds revealed by three-dimensional atomic mapping
Authors: Zhao Jiong , Deng Qingming , Ly Thuc Hue , Han Gang Hee , Sandeep Gorantla , Rümmeli Mark H 
Published: November 2015

AbstractThe great application potential for two-dimensional (2D) membranes (MoS2, WSe2, graphene and so on) aroused much effort to understand their fundamental mechanical properties. The out-of-plane bending rigidity is the key factor that controls the membrane morphology under external fields. Herein we provide an easy method to reconstruct the 3D structures of the folded edges of these 2D membranes on the atomic scale, using high-resolution (S)TEM images. After quantitative comparison with continuum mechanics shell model, it is verified that the bending behaviour of the studied 2D materials can be well explained by the linear elastic shell model. And the bending rigidities can thus be derived by fitting with our experimental results. Recall almost only theoretical approaches can access the bending properties of these 2D membranes before, now a new experimental method to measure the bending rigidity of such flexible and atomic thick 2D membranes is proposed.
Delaying aging is neuroprotective in Parkinson’s disease: a genetic analysis in C. elegans models
Authors: Cooper Jason F , Dues Dylan J , Spielbauer Katie K , Machiela Emily , Senchuk Megan M , Van Raamsdonk Jeremy M 
Published: November 2015

AbstractAging is the greatest risk factor for the development of Parkinson’s disease (PD). However, the role of aging in the pathogenesis of PD is not known and it is currently uncertain why the symptoms take many decades to develop when inherited mutations that cause the disease can be present from birth. We hypothesize that there are specific changes that take place during the aging process that make cells susceptible to disease-causing mutations that are well-tolerated at younger ages. If so, then interventions that increase lifespan should be beneficial in the treatment of PD. To test this hypothesis, we used the powerful genetics of C. elegans, as this worm has been used extensively in aging research. We crossed transgenic worm models of PD expressing either human mutant α-synuclein (A53T) or LRRK2 (G2019S) with the long-lived insulin-IGF1 receptor mutant, daf-2. The daf-2 mutation increased the lifespan of both PD mutants. The increase in lifespan resulting from the daf-2 mutation rescued the degeneration of dopamine neurons in both worm models of PD and importantly rescued deficits in dopamine-dependent behaviors including basal slowing, ethanol avoidance, and area-restricted searching. Increasing lifespan through daf-2 mutation also delayed the formation of small aggregates in a worm model of PD expressing α-synuclein in the body wall muscle and rescued deficits in resistance to different stresses that were present in the PD mutant worms. Overall, this work suggests that slowing down the aging process may provide an effective treatment for PD.
Structural and electrical properties of catalyst-free Si-doped InAs nanowires formed on Si(111)
Authors: Park Dong Woo , Jeon Seong Gi , Lee Cheul-Ro , Lee Sang Jun , Song Jae Yong , Kim Jun Oh , Noh Sam Kyu , Leem Jae-Young , Kim Jin Soo 
Published: November 2015

AbstractWe report structural and electrical properties of catalyst-free Si-doped InAs nanowires (NWs) formed on Si(111) substrates. The average diameter of Si-doped InAs NWs was almost similar to that of undoped NWs with a slight increase in height. In the previous works, the shape and size of InAs NWs formed on metallic catalysts or patterned structures were significantly changed by introducing dopants. Even though the external shape and size of the Si-doped NWs in this work were not changed, crystal structures inside the NWs were significantly changed. For the undoped InAs NWs, both zincblende (ZB) and wurzite (WZ) structures were observed in transmission-electron microscope images, where the portion of WZ structure was estimated to be more than 30%. However, only ZB was observed with an increase in stacking fault (SF) for the Si-doped NWs. The undoped and Si-doped InAs NWs were used as channels of four-point electrical measurements with Al/Ni electrodes to investigate electrical properties. The resistivity calculated from the current-voltage curve of a Si-doped InAs NW showed 1.32 × 10−3 Ωcm, which was dramatically decreased from 10.14 × 10−3 Ωcm for the undoped InAs NW. A relatively low resistivity of catalyst-free Si-doped InAs NWs was achieved without significant change in structural dimensions.
Ligand-driven conformational changes of MurD visualized by paramagnetic NMR
Authors: Saio Tomohide , Ogura Kenji , Kumeta Hiroyuki , Kobashigawa Yoshihiro , Shimizu Kazumi , Yokochi Masashi , Kodama Kota , Yamaguchi Hiroto , Tsujishita Hideki , Inagaki Fuyuhiko 
Published: November 2015

AbstractProteins, especially multi-domain proteins, often undergo drastic conformational changes upon binding to ligands or by post-translational modifications, which is a key step to regulate their function. However, the detailed mechanisms of such dynamic regulation of the functional processes are poorly understood because of the lack of an efficient tool. We here demonstrate detailed characterization of conformational changes of MurD, a 47 kDa protein enzyme consisting of three domains, by the use of solution NMR equipped with paramagnetic lanthanide probe. Quantitative analysis of pseudocontact shifts has identified a novel conformational state of MurD, named semi-closed conformation, which is found to be the key to understand how MurD regulates the binding of the ligands. The modulation of the affinity coupled with conformational changes accentuates the importance of conformational state to be evaluated in drug design.
The accumulation mechanism of the hypoxia imaging probe “FMISO” by imaging mass spectrometry: possible involvement of low-molecular metabolites
Authors: Masaki Yukiko , Shimizu Yoichi , Yoshioka Takeshi , Tanaka Yukari , Nishijima Ken-ichi , Zhao Songji , Higashino Kenichi , Sakamoto Shingo , Numata Yoshito , Yamaguchi Yoshitaka , Tamaki Nagara , Kuge Yuji 
Published: November 2015

Abstract18F-fluoromisonidazole (FMISO) has been widely used as a hypoxia imaging probe for diagnostic positron emission tomography (PET). FMISO is believed to accumulate in hypoxic cells via covalent binding with macromolecules after reduction of its nitro group. However, its detailed accumulation mechanism remains unknown. Therefore, we investigated the chemical forms of FMISO and their distributions in tumours using imaging mass spectrometry (IMS), which visualises spatial distribution of chemical compositions based on molecular masses in tissue sections. Our radiochemical analysis revealed that most of the radioactivity in tumours existed as low-molecular-weight compounds with unknown chemical formulas, unlike observations made with conventional views, suggesting that the radioactivity distribution primarily reflected that of these unknown substances. The IMS analysis indicated that FMISO and its reductive metabolites were nonspecifically distributed in the tumour in patterns not corresponding to the radioactivity distribution. Our IMS search found an unknown low-molecular-weight metabolite whose distribution pattern corresponded to that of both the radioactivity and the hypoxia marker pimonidazole. This metabolite was identified as the glutathione conjugate of amino-FMISO. We showed that the glutathione conjugate of amino-FMISO is involved in FMISO accumulation in hypoxic tumour tissues, in addition to the conventional mechanism of FMISO covalent binding to macromolecules.
Application of density gradient for the isolation of the fecal microbial stool component and the potential use thereof
Authors: Hevia Arancha , Delgado Susana , Margolles Abelardo , Sánchez Borja 
Published: November 2015

AbstractThe idea of considering the gut microbiota as a virtual human organ has led to the concept of fecal microbiota transplantation (FMT), which has recently been extremely successful in the treatment of cases of recurrentClostridium difficileinfection. Administration of safe, viable and representative fecal microbiota is crucial for FMT. To our knowledge, suitable techniques and systematic conditions for separating the fecal microbiota from stool samples have not been thoroughly investigated. In this work we show the potential to separate stool microorganisms from the rest of fecal material using a procedure with a Nycodenz® density gradient, yielding 1010viable bacteria per two grams of feces. This procedure did not affect the original microbiota composition in terms of viability, distribution and proportions, as assessed by a phylogenetic metagenomic approach. Obtaining the fecal microbiota by concentration and separation of the microorganisms from the rest of the stool components would allow the standardization of its recovery and its long-term preservation. FMT or similar microbiota restoration therapies could be used for the treatment of several disorders, or even for aesthetic purposes, so the method described in our work may contribute to the setting of the basis for the development of safe and standardized products.
Morphology and Performance of Polymer Solar Cell Characterized by DPD Simulation and Graph Theory
Authors: Du Chunmiao , Ji Yujin , Xue Junwei , Hou Tingjun , Tang Jianxin , Lee Shuit-Tong , Li Youyong 
Published: November 2015

AbstractThe morphology of active layers in the bulk heterojunction (BHJ) solar cells is critical to the performance of organic photovoltaics (OPV). Currently, there is limited information for the morphology from transmission electron microscopy (TEM) techniques. Meanwhile, there are limited approaches to predict the morphology /efficiency of OPV. Here we use Dissipative Particle Dynamics (DPD) to determine 3D morphology of BHJ solar cells and show DPD to be an efficient approach to predict the 3D morphology. Based on the 3D morphology, we estimate the performance indicator of BHJ solar cells by using graph theory. Specifically, we study poly (3-hexylthiophene)/[6, 6]-phenyl-C61butyric acid methyl ester (P3HT/PCBM) BHJ solar cells. We find that, when the volume fraction of PCBM is in the region 0.4 ∼ 0.5, P3HT/PCBM will show bi-continuous morphology and optimum performance, consistent with experimental results. Further, the optimum temperature (413 K) for the morphology and performance of P3HT/PCBM is in accord with annealing results. We find that solvent additive plays a critical role in the desolvation process of P3HT/PCBM BHJ solar cell. Our approach provides a direct method to predict dynamic 3D morphology and performance indicator for BHJ solar cells.
New HDAC6-mediated deacetylation sites of tubulin in the mouse brain identified by quantitative mass spectrometry
Authors: Liu Ningning , Xiong Yun , Li Shanshan , Ren Yiran , He Qianqian , Gao Siqi , Zhou Jun , Shui Wenqing 
Published: November 2015

AbstractThe post-translational modifications (PTMs) occurring on microtubules have been implicated in the regulation of microtubule properties and functions. Acetylated K40 of α-tubulin, a hallmark of long-lived stable microtubules, is known to be negatively controlled by histone deacetylase 6 (HDAC6). However, the vital roles of HDAC6 in microtubule-related processes such as cell motility and cell division cannot be fully explained by the only known target site on tubulin. Here, we attempt to comprehensively map lysine acetylation sites on tubulin purified from mouse brain tissues. Furthermore, mass spectrometry-based quantitative comparison of acetylated peptides from wild-type vs HDAC6 knockout mice allowed us to identify six new deacetylation sites possibly mediated by HDAC6. Thus, adding new sites to the repertoire of HDAC6-mediated tubulin deacetylation events would further our understanding of the multi-faceted roles of HDAC6 in regulating microtubule stability and cellular functions.
Effective Temperature and Universal Conductivity Scaling in Organic Semiconductors
Authors: Abdalla Hassan , van de Ruit Kevin , Kemerink Martijn 
Published: November 2015

AbstractWe investigate the scalability of the temperature- and electric field-dependence of the conductivity of disordered organic semiconductors to ‘universal’ curves by two different but commonly employed methods; by so-called universal scaling and by using the effective temperature concept. Experimentally both scaling methods were found to be equally applicable to the out-of-plane charge transport in PEDOT:PSS thin films of various compositions. Both methods are shown to be equivalent in terms of functional dependence and to have identical limiting behavior. The experimentally observed scaling behavior can be reproduced by a numerical nearest-neighbor hopping model, accounting for the Coulomb interaction, the high charge carrier concentration and the energetic disorder. The underlying physics can be captured in a simple empirical model, describing the effective temperature of the charge carrier distribution as the outcome of a heat balance between Joule heating and (effective) temperature-dependent energy loss to the lattice.
Ionic liquids and their bases: Striking differences in the dynamic heterogeneity near the glass transition
Authors: Grzybowska K. , Grzybowski A. , Wojnarowska Z. , Knapik J. , Paluch M. 
Published: November 2015

AbstractIonic liquids (ILs) constitute an active field of research due to their important applications. A challenge for these investigations is to explore properties of ILs near the glass transition temperature Tg, which still require our better understanding. To shed a new light on the issues, we measured ILs and their base counterparts using the temperature modulated calorimetry. We performed a comparative analysis of the dynamic heterogeneity at Tgfor bases and their salts with a simple monoatomic anion (Cl–). Each pair of ionic and non-ionic liquids is characterized by nearly the same chemical structure but their intermolecular interactions are completely different. We found that the size of the dynamic heterogeneity of ILs near Tgis considerably smaller than that established for their dipolar counterparts. Further results obtained for several other ILs near Tgadditionally strengthen the conclusion about the relatively small size of the dynamic heterogeneity of molecular systems dominated by electrostatic interactions. Our finding opens up new perspectives on designing different material properties depending on intermolecular interaction types.