bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of imaging mass spectrometry for the molecular diagnosis of human breast tumors
Authors: Mao Xinxin , He Jiuming , Li Tiegang , Lu Zhaohui , Sun Jian , Meng Yunxiao , Abliz Zeper , Chen Jie 
Published: February 2016

AbstractDistinguishing breast invasive ductal carcinoma (IDC) and breast ductal carcinoma in situ (DCIS) is a key step in breast surgery, especially to determine whether DCIS is associated with tumor cell micro-invasion. However, there is currently no reliable method to obtain molecular information for breast tumor analysis during surgery. Here, we present a novel air flow-assisted ionization (AFAI) mass spectrometry imaging method that can be used in ambient environments to differentiate breast cancer by analyzing lipids. In this study, we demonstrate that various subtypes and histological grades of IDC and DCIS can be discriminated using AFAI-MSI: phospholipids were more abundant in IDC than in DCIS, whereas fatty acids were more abundant in DCIS than in IDC. The classification of specimens in the subtype and grade validation sets showed 100% and 78.6% agreement with the histopathological diagnosis, respectively. Our work shows the rapid classification of breast cancer utilizing AFAI-MSI. This work suggests that this method could be developed to provide surgeons with nearly real-time information to guide surgical resections.
Structural Insights into the Tetrameric State of Aspartate-β-semialdehyde Dehydrogenases from Fungal Species
Authors: Li Qinqin , Mu Zhixia , Zhao Rong , Dahal Gopal , Viola Ronald E. , Liu Tao , Jin Qi , Cui Sheng 
Published: February 2016

AbstractAspartate-β-semialdehyde dehydrogenase (ASADH) catalyzes the second reaction in the aspartate pathway, a pathway required for the biosynthesis of one fifth of the essential amino acids in plants and microorganisms. Microarray analysis of a fungal pathogen T. rubrum responsible for most human dermatophytoses identified the upregulation of ASADH (trASADH) expression when the fungus is exposed to human skin, underscoring its potential as a drug target. Here we report the crystal structure of trASADH, revealing a tetrameric ASADH with a GAPDH-like fold. The tetramerization of trASADH was confirmed by sedimentation and SAXS experiments. Native PAGE demonstrated that this ASADH tetramerization is apparently universal in fungal species, unlike the functional dimer that is observed in all bacterial ASADHs. The helical subdomain in dimeric bacteria ASADH is replaced by the cover loop in archaeal/fungal ASADHs, presenting the determinant for this altered oligomerization. Mutations that disrupt the tetramerization of trASADH also abolish the catalytic activity, suggesting that the tetrameric state is required to produce the active fungal enzyme form. Our findings provide a basis to categorize ASADHs into dimeric and tetrameric enzymes, adopting a different orientation for NADP binding and offer a structural framework for designing drugs that can specifically target the fungal pathogens.
Multisensory body representation in autoimmune diseases
Authors: Finotti Gianluca , Costantini Marcello 
Published: February 2016

AbstractBody representation has been linked to the processing and integration of multisensory signals. An outstanding example of the pivotal role played by multisensory mechanisms in body representation is the Rubber Hand Illusion (RHI). In this paradigm, multisensory stimulation induces a sense of ownership over a fake limb. Previous work has shown high interindividual differences in the susceptibility to the RHI. The origin of this variability remains largely unknown. Given the tight and bidirectional communication between the brain and the immune system, we predicted that the origin of this variability could be traced, in part, to the immune system’s functioning, which is altered by several clinical conditions, including Coeliac Disease (CD). Consistent with this prediction, we found that the Rubber Hand Illusion is stronger in CD patients as compared to healthy controls. We propose a biochemical mechanism accounting for the dependency of multisensory body representation upon the Immune system. Our finding has direct implications for a range of neurological, psychiatric and immunological conditions where alterations of multisensory integration, body representation and dysfunction of the immune system co-exist.
Choroidal vascularity index as a measure of vascular status of the choroid: Measurements in healthy eyes from a population-based study
Authors: Agrawal Rupesh , Gupta Preeti , Tan Kara-Anne , Cheung Chui Ming Gemmy , Wong Tien-Yin , Cheng Ching-Yu 
Published: February 2016

AbstractThe vascularity of the choroid has been implicated in the pathogenesis of various eye diseases. To date, no established quantifiable parameters to estimate vascular status of the choroid exists. Choroidal vascularity index (CVI) may potentially be used to assess vascular status of the choroid. We aimed to establish normative database for CVI and identify factors associated with CVI in healthy eyes. In this population-based study on 345 healthy eyes, choroidal enhanced depth imaging optical coherence tomography scans were segmented by modified image binarization technique. Total subfoveal choroidal area (TCA) was segmented into luminal (LA) and stromal (SA) area. CVI was calculated as the proportion of LA to TCA. Linear regression was used to identify ocular and systemic factors associated with CVI and subfoveal choroidal thickness (SFCT). Subfoveal CVI ranged from 60.07 to 71.27% with a mean value of 65.61 ± 2.33%. CVI was less variable than SFCT (coefficient of variation for CVI was 3.55 vs 40.30 for SFCT). Higher CVI was associated with thicker SFCT, but not associated with most physiological variables. CVI was elucidated as a significant determinant of SFCT. While SFCT was affected by many factors, CVI remained unaffected suggesting CVI to be a more robust marker of choroidal diseases.
A Biotin Biosynthesis Gene Restricted to Helicobacter
Authors: Bi Hongkai , Zhu Lei , Jia Jia , Cronan John E. 
Published: February 2016

AbstractIn most bacteria the last step in synthesis of the pimelate moiety of biotin is cleavage of the ester bond of pimeloyl-acyl carrier protein (ACP) methyl ester. The paradigm cleavage enzyme is Escherichia coli BioH which together with the BioC methyltransferase allows synthesis of the pimelate moiety by a modified fatty acid biosynthetic pathway. Analyses of the extant bacterial genomes showed that bioH is absent from many bioC-containing bacteria and is replaced by other genes. Helicobacter pylori lacks a gene encoding a homologue of the known pimeloyl-ACP methyl ester cleavage enzymes suggesting that it encodes a novel enzyme that cleaves this intermediate. We isolated the H. pylori gene encoding this enzyme, bioV, by complementation of an E. coli bioH deletion strain. Purified BioV cleaved the physiological substrate, pimeloyl-ACP methyl ester to pimeloyl-ACP by use of a catalytic triad, each member of which was essential for activity. The role of BioV in biotin biosynthesis was demonstrated using a reconstituted in vitro desthiobiotin synthesis system. BioV homologues seem the sole pimeloyl-ACP methyl ester esterase present in the Helicobacter species and their occurrence only in H. pylori and close relatives provide a target for development of drugs to specifically treat Helicobacter infections.
Subtropical Potential Vorticity Intrusion Drives Increasing Tropospheric Ozone over the Tropical Central Pacific
Authors: Nath Debashis , Chen Wen , Graf Hans-F. , Lan Xiaoqing , Gong Hainan , Nath Reshmita , Hu Kaiming , Wang Lin 
Published: February 2016

AbstractDrawn from multiple reanalysis datasets, an increasing trend and westward shift in the number of Potential Vorticity intrusion events over the Pacific are evident. The increased frequency can be linked to a long-term trend in upper tropospheric equatorial westerly wind and subtropical jets during boreal winter to spring. These may be resulting from anomalous warming and cooling over the western Pacific warm pool and the tropical eastern Pacific, respectively. The intrusions brought dry and ozone rich air of stratospheric origin deep into the tropics. In the tropical upper troposphere, interannual ozone variability is mainly related to convection associated with El Niño/Southern Oscillation. Zonal mean stratospheric overturning circulation organizes the transport of ozone rich air poleward and downward to the high and midlatitudes leading there to higher ozone concentration. In addition to these well described mechanisms, we observe a long-term increasing trend in ozone flux over the northern hemispheric outer tropical (10–25°N) central Pacific that results from equatorward transport and downward mixing from the midlatitude upper troposphere and lower stratosphere during PV intrusions. This increase in tropospheric ozone flux over the Pacific Ocean may affect the radiative processes and changes the budget of atmospheric hydroxyl radicals.
Structure of ring-shaped Aβ42 oligomers determined by conformational selection
Authors: Tran Linh , Basdevant Nathalie , Prévost Chantal , Ha-Duong Tâp 
Published: February 2016

AbstractThe oligomerization of amyloid beta (Aβ) peptides into soluble non-fibrillar species plays a critical role in the pathogenesis of Alzheimer’s disease. However, it has been challenging to characterize the tertiary and quaternary structures of Aβ peptides due to their disordered nature and high aggregation propensity. In this work, replica exchange molecular dynamics simulations were used to explore the conformational space of Aβ42 monomer. Among the most populated transient states, we identified a particular conformation which was able to generate ring-shaped pentamers and hexamers, when docked onto itself. The structures of these aggregates were stable during microsecond all-atom MD simulations in explicit solvent. In addition to high resolution models of these oligomers, this study provides support for the conformational selection mechanism of Aβ peptide self-assembly.
The time course of visuo-spatial working memory updating revealed by a retro-cuing paradigm
Authors: Schneider Daniel , Mertes Christine , Wascher Edmund 
Published: February 2016

AbstractWe investigated the influence of non-cued working memory representations on further information processing. A retro-cue indicated if items on the left or right side of a previous memory array remained relevant. Subsequently, a central probe item was presented with a varying stimulus onset asynchrony (SOA: 300, 400, 600, 1000, 1800 ms). Participants had to state whether this stimulus was shown on the cued side of the memory array. The probe was either a cued, non-cued or new item. Non-cued probes were associated with delayed response times and an increased frontal negativity from 400–600 ms indicating a higher processing conflict compared to new probes. These effects were strongest for the 300 and 400 ms SOAs and decreased in longer SOA conditions, pointing toward a benefit when there was sufficient time for working memory updating. Furthermore, contralateral negativities at posterior (PCN) and anterior sites (ADAN) reflected the attentional orienting toward cued information while selective retention was associated with a sustained suppression of posterior induced alpha power contralateral to retro-cue direction. Results suggest that retro-cue induced updating of visuo-spatial working memory requires about 500 ms to transfer the non-cued contents into a passive and fragile short-term memory state with less impact on ongoing information processing.
A synergistic blocking effect of Mg2+ and spermine on the inward rectifier K+ (Kir2.1) channel pore
Authors: Huang Chiung-Wei , Kuo Chung-Chin 
Published: February 2016

AbstractInward rectifier K+ channels (Kir2.1) exhibit an extraordinary rectifying feature in the current–voltage relationship. We have previously showed that the bundle–crossing region of the transmembrane domain constitutes the crucial segment responsible for the polyamine block. In this study, we demonstrated that the major blocking effect of intracellular Mg2+ on Kir2.1 channels is also closely correlated with K+ current flow and the coupled movements of Mg2+ and K+ seem to happen in the same flux–coupling segment of the pore as polyamines. With a preponderant outward K+ flow, intracellular Mg2+ would also be pushed to and thus stay at the outermost site of a flux–coupling segment in the bundle–crossing region of Kir2.1 channels to block the pore, although with a much lower apparent affinity than spermine (SPM). However, in contrast to the evident possibilities of outward exit of SPM through the channel pore especially during strong membrane depolarization, intracellular Mg2+ does not seem to traverse the Kir2.1 channel pore in any case. Intracellular Mg2+ and SPM therefore may have a synergistic action on the pore–blocking effect, presumably via prohibition of the outward exit of the higher–affinity blocking SPM by the lower–affinity Mg2+.
Residual force enhancement following shortening is speed-dependent
Authors: Fortuna Rafael , Power Geoffrey A. , Mende Esther , Seiberl Wolfgang , Herzog Walter 
Published: February 2016

AbstractThe steady-state isometric force following active muscle shortening or lengthening is smaller (force depression; FD) or greater (residual force enhancement; RFE) than a purely isometric contraction at the corresponding length. The mechanisms underlying these phenomena are not explained within the context of the cross-bridge theory and are rarely studied in concert. Previous studies have shown RFE to be speed-independent. In the present study, we investigated if RFE preceded by active shortening is time-dependent by electrically evoking RFE in the human adductor pollicis muscle. The results shown that a slow stretch following FD fully re-established RFE compared to higher speeds of stretch. The mechanism(s) responsible for the recovery of RFE following a preceding shortening contraction (FD) might be associated with the recovery of cross-bridge based force and/or the re-engagement of a passive structural element (titin). Voluntary interaction with one’s environment involves highly coordinated shortening and lengthening muscle contractions. Therefore comprehending these history-dependent muscle properties in the context of movement control is paramount in understanding the behavior of in vivo motor control.
Chromatic-aberration-corrected diffractive lenses for ultra-broadband focusing
Authors: Wang Peng , Mohammad Nabil , Menon Rajesh 
Published: February 2016

AbstractWe exploit the inherent dispersion in diffractive optics to demonstrate planar chromatic-aberration-corrected lenses. Specifically, we designed, fabricated and characterized cylindrical diffractive lenses that efficiently focus the entire visible band (450 nm to 700 nm) onto a single line. These devices are essentially pixelated, multi-level microstructures. Experiments confirm an average optical efficiency of 25% for a three-wavelength apochromatic lens whose chromatic focus shift is only 1.3 μm and 25 μm in the lateral and axial directions, respectively. Super-achromatic performance over the continuous visible band is also demonstrated with averaged lateral and axial focus shifts of only 1.65 μm and 73.6 μm, respectively. These lenses are easy to fabricate using single-step grayscale lithography and can be inexpensively replicated. Furthermore, these devices are thin (<3 μm), error tolerant, has low aspect ratio (<1:1) and offer polarization-insensitive focusing, all significant advantages compared to alternatives that rely on metasurfaces. Our design methodology offers high design flexibility in numerical aperture and focal length and is readily extended to 2D.
Seasonal variability of faecal indicator bacteria numbers and die-off rates in the Red River basin, North Viet Nam
Authors: Nguyen Huong Thi Mai , Le Quynh Thi Phuong , Garnier J. , Janeau J.-L. , Rochelle-Newall E. 
Published: February 2016

AbstractThe Red River is the second largest river in Viet Nam and constitutes the main water source for a large percentage of the population of North Viet Nam. Here we present the results of an annual survey of Escherichia coli (EC) and Total Coliforms (TC) in the Red River basin, North Viet Nam. The objective of this work was to obtain information on faecal indicator bacteria (FIB) numbers over an annual cycle and, secondly, to determine the die-off rates of these bacterial indicators. Monthly observations at 10 stations from July 2013–June 2014 showed that TC and EC reached as high as 39100 cfu (colony forming units) 100 ml−1 and 15300 colonies 100 ml−1, respectively. We observed a significant seasonal difference for TC (p < 0.05) with numbers being higher during the wet season. In contrast, no significant seasonal difference was found for EC. The FIB die-off rates ranged from 0.01 d−1 to a maximum of 1.13 d−1 for EC and from 0.17 d−1 to 1.33 d−1 for TC. Die-off rates were significantly higher for free bacteria than for total (free + particle attached) bacteria, suggesting that particle attachment provided a certain level of protection to FIB in this system.
Prediction of orthostatic hypotension in multiple system atrophy and Parkinson disease
Authors: Sun Zhanfang , Jia Dandan , Shi Yuting , Hou Xuan , Yang Xiaosu , Guo Jifeng , Li Nan , Wang Junling , Sun Qiying , Zhang Hainan , Lei Lifang , Shen Lu , Yan Xinxiang , Xia Kun , Jiang Hong , Tang Beisha 
Published: February 2016

AbstractOrthostatic hypotension (OH) is common in multiple system atrophy (MSA) and Parkinson disease (PD), generally assessed through a lying-to-standing orthostatic test. However, standing blood pressure may not be available due to orthostatic intolerance or immobilization for such patients. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were successively measured in supine, sitting, and standing positions in patients with MSA and PD. Receiver operating characteristic analysis was used to evaluate diagnostic performance of the drops of sitting SBP or DBP. OH and severe OH were respectively regarded as “gold standard”. The drops of SBP in standing position were associated with increased disease severity for MSA and correlated with age for PD. In MSA group, drops in sitting SBP ≥ 14 mmHg or DBP ≥ 6 mmHg had highest validity for prediction of OH, and drops in sitting SBP ≥ 18 mmHg or DBP ≥ 8 mmHg for severe OH. In PD group, drops in sitting SBP ≥ 10 mmHg or DBP ≥ 6 mmHg had highest validity for prediction of OH. The lying-to-sitting orthostatic test is an alternative method for detection of OH in MSA and PD, especially when standing BP could not be validly measured due to various reasons.
Characterization of SCO4439, a D-alanyl-D-alanine carboxypeptidase involved in spore cell wall maturation, resistance and germination in Streptomyces coelicolor
Authors: Rioseras Beatriz , Yagüe Paula , López-García María Teresa , Gonzalez-Quiñonez Nathaly , Binda Elisa , Marinelli Flavia , Manteca Angel 
Published: February 2016

AbstractThis work contributes to the understanding of cell wall modifications during sporulation and germination inStreptomycesby assessing the biological function and biochemical properties of SCO4439, a D-alanyl-D-alanine carboxypeptidase (DD-CPase) constitutively expressed during development. SCO4439 harbors a DD-CPase domain and a putative transcriptional regulator domain, separated by a putative transmembrane region. The recombinant protein shows thatDD-CPase activity is inhibited by penicillin G. The spores of theSCO4439::Tn5062mutant are affected in their resistance to heat and acid and showed a dramatic increase in swelling during germination. The mycelium of theSCO4439::Tn5062mutant is more sensitive to glycopeptide antibiotics (vancomycin and teicoplanin). The DD-CPase domain and the hydrophobic transmembrane region are highly conserved inStreptomycesand both are essential for complementing the wild type phenotypes in the mutant. A model for the biological mechanism behind the observed phenotypes is proposed, in which SCO4439 DD-CPase releases D-Ala from peptidoglycan (PG) precursors, thereby reducing the substrate pool for PG crosslinking (transpeptidation). PG crosslinking regulates spore physical resistance and germination and modulates mycelium resistance to glycopeptides. This study is the first demonstration of the role of a DD-CPase in the maturation of the spore cell wall.
Auditory word recognition across the lifespan
Authors: Blumenfeld Henrike K. , Schroeder Scott R. , Bobb Susan C. , Freeman Max R. , Marian Viorica 
Published: February 2016

Abstract
Recent research suggests that bilingual experience reconfigures linguistic and nonlinguistic cognitive processes. We examined the relationship between linguistic competition resolution and nonlinguistic cognitive control in younger and older adults who were either bilingual or monolingual. Participants heard words in English and identified the referent among four pictures while eye-movements were recorded. Target pictures (e.g., cab) appeared with a phonological competitor picture (e.g., cat) and two filler pictures. After each eye-tracking trial, priming probes assessed residual activation and inhibition of target and competitor words. When accounting for processing speed, results revealed that age-related changes in activation and inhibition are smaller in bilinguals than in monolinguals. Moreover, younger and older bilinguals, but not monolinguals, recruited similar inhibition mechanisms during word identification and during a nonlinguistic Stroop task. Results suggest that, during lexical access, bilinguals show more consistent competition resolution and recruitment of cognitive control across the lifespan than monolinguals.
The effect of language skills on dementia in a Swedish longitudinal cohort
Authors: Ljungberg Jessica K. , Hansson Patrik , Adolfsson Rolf , Nilsson Lars-Göran 
Published: February 2016

Abstract
Recent findings indicate that bilingualism delay the onset of dementia. Using data from the Betula longitudinal cohort study on memory, health and aging (www.betula.su.se) the issue of a possible protective effect of bilingualism was addressed.
Monolingual (n = 736) and bilingual (n = 82) participants (≥ 60 years) without dementia at inclusion were followed for incident dementia over a time-period up to 10 years. In total, 112 participants developed dementia. Analyses were performed with Cox proportional hazards regression adjusted for age, sex, and presence/absence of the Apolipoprotein E (APOE) ɛ4 allele, with dementia outcome as the dependent variable.
Results showed no delayed onset of dementia in bilinguals compared to monolinguals. However, because of the findings from a study using participants from the same population showing beneficial longitudinal effects of bilingualism on episodic memory; we argue that our results may depend on the frequency of use of the second language after retirement.