bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metallothionein deficiency impacts copper accumulation and redistribution in leaves and seeds of Arabidopsis
Authors: R. Benatti Matheus , Yookongkaew Nimnara , Meetam Metha , Guo Woei‐Jiun , Punyasuk Napassorn , AbuQamar Synan , Goldsbrough Peter 
Published: March 2014

Summary

Most angiosperm genomes contain several genes encoding metallothionein (MT) proteins that can bind metals including copper (Cu) and zinc (Zn). Metallothionein genes are highly expressed under various conditions but there is limited information about their function. We have studied Arabidopsis mutants that are deficient in multiple MTs to learn about the functions of MTs in plants.

T‐DNA insertions were identified in four of the five Arabidopsis MT genes expressed in vegetative tissues. These were crossed to produce plants deficient in four MTs (mt1a/mt2a/mt2b/mt3).

The concentration of Cu was lower in seeds but higher in old leaves of the quad‐MT mutant compared to wild‐type plants. Experiments with stable isotopes showed that Cu in seeds came from two sources: directly from roots and via remobilization from other organs. Mobilization of Cu out of senescing leaves was disrupted in MT‐deficient plants. Tolerance to Cu, Zn and paraquat was unaffected by MT deficiency but these plants were slightly more sensitive to cadmium (Cd). The quad‐MT mutant showed no change in resistance to a number of microbial pathogens, or in the progression of leaf senescence.

Although these MTs are not required to complete the plant's life cycle, MTs are important for Cu homeostasis and distribution in Arabidopsis.
The root indeterminacy‐to‐determinacy developmental switch is operated through a folate‐dependent pathway in Arabidopsis thaliana
Authors: Reyes‐Hernández Blanca Jazmín , Srivastava Avinash C. , Ugartechea‐Chirino Yamel , Shishkova Svetlana , Ramos‐Parra Perla A. , Lira‐Ruan Verónica , Díaz de la Garza Rocío I. , Dong Gaofeng , Moon Jun‐Cheol , Blancaflor Elison B. , Dubrovsky Joseph G. 
Published: March 2014

Summary

Roots have both indeterminate and determinate developmental programs. The latter is preceded by the former. It is not well understood how the indeterminacy‐to‐determinacy switch (IDS) is regulated.

We isolated a moots koom2 (mko2; ‘short root’ in Mayan) Arabidopsis thaliana mutant with determinate primary root growth and analyzed the root apical meristem (RAM) behavior using various marker lines. Deep sequencing and genetic and pharmacological complementation permitted the identification of a point mutation in the FOLYLPOLYGLUTAMATE SYNTHETASE1 (FPGS1) gene responsible for the mko2 phenotype.

Wild‐type FPGS1 is required to maintain the IDS in the ‘off’ state. When FPGS1 function is compromised, the IDS is turned on and the RAM becomes completely consumed. The polyglutamate‐dependent pathway of the IDS involves activation of the quiescent center independently of auxin gradients and regulatory modules participating in RAM maintenance (WUSCHEL‐RELATED HOMEOBOX5 (WOX5), PLETHORA, and SCARECROW (SCR)). The mko2 mutation causes drastic changes in folate metabolism and also affects lateral root primordium morphogenesis but not initiation.

We identified a metabolism‐dependent pathway involved in the IDS in roots. We suggest that the root IDS represents a specific developmental pathway that regulates RAM behaviour and is a different level of regulation in addition to RAM maintenance.
Le récit de soi : une mémoire au futur
Authors: Moioli Aurélie 
Published: March 2014

Cet article met en évidence la tension prospective de la mémoire romantique en comparant deux récits autobiographiques – la Konjektural‐Biographie de Jean Paul (1799) et les Ultime lettere di Jacopo Ortis d'Ugo Foscolo (1817). Il montre que le récit de soi pointe vers l'avenir et vers le possible. À rebours du geste rétrospectif qui caractérise traditionnellement l'autobiographie, les œuvres originales de Jean Paul et d'Ugo Foscolo imaginent la vie à venir du je. Elles sont prospectives parce qu'elles relèvent de la « conjecture » et de l'anticipation, de la prophétie et de la promesse. Ce regard prospectif est lié à la présence de la mort qui hante l'autobiographe et le transforme en spectre. La figure du spectre, qui se trouve au croisement d'une réflexion sur le temps et sur l'imagination, permet d’éclairer le fonctionnement complexe de la mémoire – de la mémoire individuelle et collective. Le récit de soi est un espace spectral qui disjoint le temps et qui cependant contient les germes du futur. Cette tension vers l'avenir a un sens éminemment politique et éthique pour Jean Paul et Ugo Foscolo qui écrivent ces vies conjecturales au sortir des révolutions et en réaction aux violences de l'Histoire.
Origins and early evolution of arthropods
Authors: Edgecombe Gregory D. , Legg David A. 
Published: March 2014

AbstractPhylogenomics reconstructs an arthropod tree in which a monophyletic Arthropoda splits into Pycnogonida + Euchelicerata and Myriapoda + Pancrustacea. The same chelicerate–mandibulate groups are retrieved with morphological data sets, including those encompassing most taxa known from Palaeozoic Konservat‐Lagerstätten. With respect to the interrelationships of the three extant clades of Panarthropoda, a sister group relationship between Onychophora and Arthropoda is endorsed by transcriptomics and microRNAs, although this hypothesis forces homoplasy in characters of the segmental ganglia that are shared by tardigrades and arthropods. Cambrian lobopodians, dinocaridids, bivalved arthropods and fuxianhuiids document the successive appearance of characteristic arthropod features in the stem lineage of Euarthropoda (crown‐group arthropods). Molecular dating suggests that arthropods had their origin and initial diversification in the Ediacaran, but no convincing palaeontological evidence for Panarthropoda is available until the earliest Cambrian.
Nectar secretion dynamic links pollinator behavior to consequences for plant reproductive success in the ornithophilous mistletoe Psittacanthus robustus
Authors: Guerra T. J. , Galetto L. , Silva W. R. 
Published: March 2014

AbstractThe mistletoe Psittacanthus robustus was studied as a model to link flower phenology and nectar secretion strategy to pollinator behaviour and the reproductive consequences for the plant. The bright‐coloured flowers presented diurnal anthesis, opened asynchronously throughout the rainy season and produced copious dilute nectar as the main reward for pollinators. Most nectar was secreted just after flower opening, with little sugar replenishment after experimental removals. During the second day of anthesis in bagged flowers, the flowers quickly reabsorbed the offered nectar. Low values of nectar standing crop recorded in open flowers can be linked with high visitation rates by bird pollinators. Eight hummingbirds and two passerines were observed as potential pollinators. The most frequent flower visitors were the hummingbirds Eupetomena macroura and Colibri serrirostris, which actively defended flowering mistletoes. The spatial separation between anthers, stigma and nectar chamber promotes pollen deposition on flapping wings of hovering hummingbirds that usually probe many flowers per visit. Seed set did not differ between hand‐, self‐ and cross‐pollinated flowers, but these treatments set significantly more seeds than flowers naturally exposed to flower visitors. We suggest that the limitation observed in the reproductive success of this plant is not related to pollinator scarcity, but probably to the extreme frequency of visitation by territorial hummingbirds. We conclude that the costs and benefits of plant reproduction depend on the interaction strength between flowers and pollinators, and the assessment of nectar secretion dynamics, pollinator behaviour and plant breeding system allows clarification of the complexity of such associations.
Physical Attractiveness and Social Status
Authors: Frevert Tonya K. , Walker Lisa Slattery 
Published: March 2014

AbstractIn this article, we outline the evidence regarding the status effects of physical attractiveness, paying particular attention to outcomes in the areas of jobs, crime, performance evaluations, power, health perceptions, and exchange. The framework of status characteristics theory is used to guide our explication. The role of attractiveness in marketing is also discussed. While the literature generally supports the idea that attractiveness is good for people, we also consider evidence that beauty can be detrimental for some individuals in certain situations. Issues of race and gender are also considered as well as future research directions.
Hybrid Masculinities: New Directions in the Sociology of Men and Masculinities
Authors: Bridges Tristan , Pascoe C. J. 
Published: March 2014

AbstractHybrid masculinity refers to men's selective incorporation of performances and identity elements associated with marginalized and subordinated masculinities and femininities. We use recent theorization of hybrid masculinities to critically review theory and research that seeks to make sense of contemporary transformations in masculinity. We suggest that research broadly supports three distinct consequences associated with recent changes in performances and politics of masculinity that work to obscure the tenacity of gendered inequality. Hybrid masculinities (i) symbolically distance men from hegemonic masculinity; (ii) situate the masculinities available to young, White, heterosexual men as somehow less meaningful than the masculinities associated with various marginalized and subordinated Others; and (iii) fortify existing social and symbolic boundaries in ways that often work to conceal systems of power and inequality in historically new ways.
Drug Use Among Latino Youth: Two Popular Criminological Perspectives Infused with Latino Culture
Authors: Kopak Albert M. 
Published: March 2014

AbstractDrug use among Latino youth in the United States is a persistent problem which has been examined from a variety of academic disciplines, including psychology, sociology, and social work. These share significant overlap with mainstream criminological approaches to explaining delinquency and drug use, which have virtually ignored these issues or investigated them exclusively from an ethnocentric perspective. The naturally multidisciplinary topics of Latino youth, culture, and drug use can be readily situated within two popular frameworks (social control and strain), and these can also be enriched with core aspects of Latino culture. Complimentary cultural values enhance these two perspectives and significantly contribute to our criminological understanding of some of the reasons why Latino youth become involved in drug use. After reviewing our current knowledge on this subject, suggestions are made for ways future criminological research can more deeply explore these rich cultural reasons related to why some Latino youth use drugs. This can ultimately help inform more relevant drug use reduction strategies and also decrease the proportion of Latino youth who come into contact with the criminal justice system for drug‐related offenses.
Microparticle profile and procoagulant activity of fresh‐frozen plasma is affected by whole blood leukoreduction rather than 24‐hour room temperature hold
Authors: Chan Kasey Sze‐Kei , Sparrow Rosemary L. 
Published: March 2014

BackgroundMicroparticles (MPs) are small phospholipid‐containing vesicles that have procoagulant properties. MPs are thought to contribute to the hemostatic potential of plasma. This study investigated the effects of whole blood (WB) hold time and leukoreduction (LR) on the MP profile and hemostatic potential of fresh‐frozen plasma (FFP).Study Design and MethodsWB units (n = 12) from healthy donors were divided into two pairs and each pair was held at 20 to 24°C for 6 or 24 hours. At the designated hold time, 1 unit from the pair was LR while the other unit was not LR. FFP was prepared by standard procedures, aliquoted, and frozen. The MP content was determined by flow cytometry using an absolute count assay and specific labels for red blood cells (CD235a), platelets (CD41), and phosphatidylserine (PS). The hemostatic potential was determined by thrombelastography (TEG) and coagulation factor assays.ResultsCompared to non‐LR‐FFP, LR‐FFP had significantly lower numbers of MPs, particularly CD41+ MPs and PS‐positive MPs (p < 0.03). LR‐FFP, compared to non‐LR‐FFP, had a slower clot formation time (p = 0.002); lower clot strength (p < 0.001); and lower Factor (F)VIII, FXII, and fibrinogen levels (p < 0.01). With longer WB hold time, the TEG profile was unchanged, although FVIII levels were decreased as expected (p < 0.01). On average FFP units met quality requirements.ConclusionLR of WB resulted in lower hemostatic potential of FFP in conjunction with depletion of MPs and coagulation factors. Longer WB hold time did not significantly affect the hemostatic potential of FFP as measured by TEG. Acceptable hemostatic quality was maintained for all FFP processing conditions studied.
Histamine inhibits the melanin‐concentrating hormone system: implications for sleep and arousal
Authors: Parks Gregory S. , Olivas Nicholas D. , Ikrar Taruna , Sanathara Nayna M. , Wang Lien , Wang Zhiwei , Civelli Olivier , Xu Xiangmin 
Published: March 2014

Key points
Melanin‐concentrating hormone (MCH) neurons express histamine‐3 receptor (H3R) mRNA but not histamine‐1 (H1R) or histamine‐2 (H2R) receptor mRNA.
Histamine inhibits MCH neurons by activating postsynaptic H3R. This effect is mediated through G protein‐dependent inwardly rectifying potassium (GIRK) channels.
Histamine may function to silence MCH neurons during wakefulness.
AbstractMelanin‐concentrating hormone (MCH)‐producing neurons are known to regulate a wide variety of physiological functions such as feeding, metabolism, anxiety and depression, and reward. Recent studies have revealed that MCH neurons receive projections from several wake‐promoting brain regions and are integral to the regulation of rapid eye movement (REM) sleep. Here, we provide evidence in both rats and mice that MCH neurons express histamine‐3 receptors (H3R), but not histamine‐1 (H1R) or histamine‐2 (H2R) receptors. Electrophysiological recordings in brain slices from a novel line of transgenic mice that specifically express the reporter ZsGreen in MCH neurons show that histamine strongly inhibits MCH neurons, an effect which is TTX insensitive, and blocked by the intracellular presence of GDP‐β‐S. A specific H3R agonist, α‐methylhistamine, mimicks the inhibitory effects of histamine, and a specific neutral H3R antagonist, VUF 5681, blocks this effect. Tertiapin Q (TPQ), a G protein‐dependent inwardly rectifying potassium (GIRK) channel inhibitor, abolishes histaminergic inhibition of MCH neurons. These results indicate that histamine directly inhibits MCH neurons through H3R by activating GIRK channels and suggest that that inhibition of the MCH system by wake‐active histaminergic neurons may be responsible for silencing MCH neurons during wakefulness and thus may be directly involved in the regulation of sleep and arousal.
Modulating effect of SIRT1 activation induced by resveratrol on Foxo1‐associated apoptotic signalling in senescent heart
Authors: Sin Thomas K. , Yu Angus P. , Yung Benjamin Y. , Yip Shea Ping , Chan Lawrence W. , Wong Cesar S. , Ying Michael , Rudd John A. , Siu Parco M. 
Published: March 2014

Key points
Cardiac function is impaired and Foxo1/Bim‐related apoptotic signalling is up‐regulated in senescent heart
Activation of SIRT1 deacetylase activity by resveratrol attenuates the Foxo1/Bim signalling axis in senescent heart
AbstractElevations of cardiomyocyte apoptosis and fibrotic deposition are major characteristics of the ageing heart. Resveratrol, a polyphenol in grapes and red wine, is known to improve insulin resistance and increase mitochondrial biogenesis through the SIRT1–PGC‐1α signalling axis. Recent studies attempted to relate SIRT1 activation by resveratrol to the regulation of apoptosis in various disease models of cardiac muscle. In the present study, we tested the hypothesis that long‐term (8‐month) treatment of resveratrol would activate SIRT1 and improve the cardiac function of senescent mice through suppression of Foxo1‐associated pro‐apoptotic signalling. Our echocardiographic measurements indicated that the cardiac systolic function measured as fractional shortening and ejection fraction was significantly reduced in aged mice when compared with the young mice. These reductions, however, were not observed in resveratrol‐treated hearts. Ageing significantly reduced the deacetylase activity, but not the protein abundance of SIRT1 in the heart. This reduction was accompanied by increased acetylation of the Foxo1 transcription factor and transactivation of its target, pro‐apoptotic Bim. Subsequent analyses indicated that pro‐apoptotic signalling measured as p53, Bax and apoptotic DNA fragmentation was up‐regulated in the heart of aged mice. In contrast, resveratrol restored SIRT1 activity and suppressed elevations of Foxo1 acetylation, Bim and pro‐apoptotic signalling in the aged heart. In parallel, resveratrol also attenuated the ageing‐induced elevations of fibrotic collagen deposition and markers of oxidative damage including 4HNE and nitrotyrosine. In conclusion, these novel data demonstrate that resveratrol mitigates pro‐apoptotic signalling in senescent heart through a deacetylation mechanism of SIRT1 that represses the Foxo1–Bim‐associated pro‐apoptotic signalling axis.
Ponto‐medullary nuclei involved in the generation of sequential pharyngeal swallowing and concomitant protective laryngeal adduction in situ
Authors: Bautista Tara G. , Dutschmann Mathias 
Published: March 2014

Key points
Laryngeal adduction is a major mechanism in sealing off entry to the trachea to prevent aspiration during swallowing.
An experimental protocol to reliably elicit sequential swallowing by oral injection of small volumes of water was developed in the in situ perfused brainstem preparation of juvenile rats.
The sequential swallowing motor pattern consists of two distinct components: (i) phasic swallowing, indicated by rhythmic sequential vagal nerve bursting, and (ii) protective laryngeal adduction, indicated by background tonic vagal discharge.
Pharmacological manipulation of the Kölliker–Fuse nucleus revealed that it specifically mediates the protective tonic laryngeal adduction, while GABAergic neurotransmission is needed in the nucleus of the solitary tract for the generation of the sequential swallowing motor pattern.
We conclude that sequential swallow motor patterning, including effective airway protection, requires balanced excitatory–inhibitory synaptic interaction within the nucleus of the solitary tract and the Kölliker–Fuse nucleus, as well as between the two nuclei.
AbstractBoth swallowing and respiration involve postinspiratory laryngeal adduction. Swallowing‐related postinspiratory neurons are likely to be located in the nucleus of the solitary tract (NTS) and those involved in respiration are found in the Kölliker–Fuse nucleus (KF). The function of KF and NTS in the generation of swallowing and its coordination with respiration was investigated in perfused brainstem preparations of juvenile rats (n = 41). Orally injected water evoked sequential pharyngeal swallowing (s‐PSW) seen as phasic, spindle‐shaped bursting of vagal nerve activity (VNA) against tonic postinspiratory discharge. KF inhibition by microinjecting isoguvacine (GABAA receptor agonist) selectively attenuated tonic postinspiratory VNA (n = 10, P < 0.001) but had no effect on frequency or timing of s‐PSW. KF disinhibition after bicuculline (GABAA receptor antagonist) microinjections caused an increase of the tonic VNA (n = 8, P < 0.01) resulting in obscured and delayed phasic s‐PSW. Occurrence of spontaneous PSW significantly increased after KF inhibition (P < 0.0001) but not after KF disinhibition (P = 0.14). NTS isoguvacine microinjections attenuated the occurrence of all PSW (n = 5, P < 0.01). NTS bicuculline microinjections (n = 6) resulted in spontaneous activation of a disordered PSW pattern and long‐lasting suppression of respiratory activity. Pharmacological manipulation of either KF or NTS also triggered profound changes in respiratory postinspiratory VNA. Our results indicate that the s‐PSW comprises two functionally distinct components. While the primary s‐PSW is generated within the NTS, a KF‐mediated laryngeal adductor reflex safeguards the lower airways from aspiration. Synaptic interaction between KF and NTS is required for s‐PSW coordination with respiration as well as for proper gating and timing of s‐PSW.
Spatio‐temporal texture (SpTeT) for distinguishing vulnerable from stable atherosclerotic plaque on dynamic contrast enhancement (DCE) MRI in a rabbit model
Authors: Wan Tao , Madabhushi Anant , Phinikaridou Alkystis , Hamilton James A. , Hua Ning , Pham Tuan , Danagoulian Jovanna , Kleiman Ross , Buckler Andrew J. 
Published: March 2014

Purpose:To develop a new spatio‐temporal texture (SpTeT) based method for distinguishing vulnerable versus stable atherosclerotic plaques on DCE‐MRI using a rabbit model of atherothrombosis.Methods:Aortic atherosclerosis was induced in 20 New Zealand White rabbits by cholesterol diet and endothelial denudation. MRI was performed before (pretrigger) and after (posttrigger) inducing plaque disruption with Russellˈs‐viper‐venom and histamine. Of the 30 vascular targets (segments) under histology analysis, 16 contained thrombus (vulnerable) and 14 did not (stable). A total of 352 voxel‐wise computerized SpTeT features, including 192 Gabor, 36 Kirsch, 12 Sobel, 52 Haralick, and 60 first‐order textural features, were extracted on DCE‐MRI to capture subtle texture changes in the plaques over the course of contrast uptake. Different combinations of SpTeT feature sets, in which the features were ranked by a minimum‐redundancy‐maximum‐relevance feature selection technique, were evaluated via a random forest classifier. A 500 iterative 2‐fold cross validation was performed for discriminating the vulnerable atherosclerotic plaque and stable atherosclerotic plaque on per voxel basis. Four quantitative metrics were utilized to measure the classification results in separating between vulnerable and stable plaques.Results:The quantitative results show that the combination of five classes of SpTeT features can distinguish between vulnerable (disrupted plaques with an overlying thrombus) and stable plaques with the best AUC values of 0.9631 ± 0.0088, accuracy of 89.98% ± 0.57%, sensitivity of 83.71% ± 1.71%, and specificity of 94.55% ± 0.48%.Conclusions:Vulnerable and stable plaque can be distinguished by SpTeT based features. The SpTeT features, following validation on larger datasets, could be established as effective and reliable imaging biomarkers for noninvasively assessing atherosclerotic risk.