bluuebunny/crossref_metadata_2025_split huggingface dataset:
Depolarization increases cellular light transmission
Authors: Tomita Minoru , Suzuki Norihiro , Tomita Yutaka , Toriumi Haruki , Osada Takashi , Unekawa Miyuki , Tatarishvili Jemal 
Published: July 2019

AbstractApplication of optical methods to human brain tissue in vivo, e.g., measuring oxyhemoglobin and deoxyhemoglobin concentration changes with near-infrared spectroscopy (NIRS), requires the a priori assumption that background optical properties remain unchanged during measurements1,2. However, fundamental knowledge about light scattering by brain cells per se remains sparse; many factors influence light transmission changes through living brain tissue, bringing into question what is being measured. We have observed slow wave-ring spreads of light transmission changes on the rat cerebral cortex during potassium-induced cortical spreading depression (CSD) and ascribed them to squeezing-out of blood from capillaries by swollen brain cells3,4. However, in rat hippocampal slices, where no blood components were involved, similar light transmission changes were observed during K+-induced CSD and ascribed to cell swelling and dendritic beading5,6,7. Here we show that two-dimensional light scattering changes occur through suspensions of osmotically swollen (depolarized) red blood cells, apparently arising from light scattering changes at the less curved, swollen surface of the steep electrochemical gradient coupled with water activity difference across the plasmic membrane. These optical property changes are likely to be relevant to interpretation of photometry or spectroscopy findings of brain tissue in vivo, where neurons are polarizing and depolarizing during brain function.
Significance tests for comparing digital gene expression profiles
Authors: Varuzza Leonardo , Gruber Arthur , Pereira Carlos 
Published: July 2019

Abstract Most of the statistical tests currently used to detect differentially expressed genes are based on asymptotic results, and perform poorly for low expression tags. Another problem is the common use of a single canonical cutoff for the significance level (p-value) of all the tags, without taking into consideration the type II error and the highly variable character of the sample size of the tags. This work reports the development of two significance tests for the comparison of digital expression profiles, based on frequentist and Bayesian points of view, respectively. Both tests are exact, and do not use any asymptotic considerations, thus producing more correct results for low frequency tags than the chi-square test. The frequentist test uses a tag-customized critical level which minimizes a linear combination of type I and type II errors. A comparison of the Bayesian and the frequentist tests revealed that they are linked by a Beta distribution function. These tests can be used alone or in conjunction, and represent an improvement over the currently available methods for comparing digital profiles.
Enforced expression of PPP1R13L increases tumorigenesis and invasion through p53-dependent and p53-independent mechanisms.
Authors: Laska Magdalena , Lowe Scott , Zender Lars , Hearn Stephen , Vogel Ulla , Jensen Uffe Birk , Bric Anka , Nexø Bjørn 
Published: July 2019

AbstractPPP1R13L was initially identified as a protein that binds to the NF-[kappa]B subunit p65/RelA and inhibits its transcriptional activity. It also binds p53 and inhibits its action. One set of experimental findings based on over-expression of PPP1R13L indicates that PPP1R13L blocks apoptosis. Another set of experiments, based on endogenous production of PPP1R13L, suggests that the protein may sometimes be pro-apoptotic. We have used primary mouse embryonic fibroblasts (MEFs), dually transformed by H-ras and Adenovirus E1A and differing in their p53 status, to explore the effects of PPP1R13L over-expression, thus examining the ability of PPP1R13L to act as an oncoprotein. We found that over-expression of PPP1R13L strongly accelerated tumor formation by ras/E1A and also resulted in an increased metastatic potential of the tumors. PPP1R13L over-expressing cells were depleted for both p53 and active p65/RelA and we found that both p53 dependent and independent apoptosis pathways were regulated by PPP1R13L. Finally, studies with the proteasome inhibitor MG132 revealed that over-expression of PPP1R13L causes faster p53 degradation, a likely explanation for the depletion of p53. Taken together, our results show that increased levels of PPP1R13L can increase tumorigenesis and furthermore pinpoint PPP1R13L as a gene that influences metastasis.
Dendritic spike induction of postsynaptic cerebellar LTP
Authors: Canepari Marco , Vogt Kaspar 
Published: July 2019

AbstractThe architecture of parallel fiber (PF) axons contacting cerebellar Purkinje neurons (PNs) retains spatial information over long distances. PF synapses can trigger local dendritic calcium spikes, but whether and how this calcium signal leads to plastic changes that decode the PF input organization is unknown. By combining voltage and calcium imaging, we show that PF-elicited calcium signals, mediated by voltage-gated calcium channels, increase non-linearly during high-frequency bursts of electrically constant calcium spikes because they locally and transiently saturate the endogenous buffer. We demonstrate that these non-linear calcium signals, independently of NMDA or metabotropic glutamate receptor activation, can induce PF long-term potentiation (LTP). Two-photon imaging in coronal slices revealed that calcium signals inducing LTP can be observed by stimulating either the PF or the ascending fiber pathway. We propose that local dendritic calcium spikes, evoked by synaptic potentials, provide a unique mechanism to spatially decode PF signals into cerebellar circuitry changes.
Guided Tissue Remineralization of Resin-Bonded Acid-Etched Dentin
Authors: Tay Franklin , Pashley David 
Published: July 2019

AbstractContemporary biomineralization strategies incorporate non-classical crystallization pathways of fluidic amorphous nanoprecursors and mesoscopic transformation. Using two functional biomimetic molecules, we previously regenerated mineralized dentin from acid-etched dentin using the Guided Tissue Remineralization (GTR) approach, with definitive intrafibrillar remineralization of type-I collagen. Degradation of denuded collagen within dentin adhesive resin-infiltrated dentin is a pertinent problem in dentin bonding. Here, we show that GTR provides a means of salvaging these degrading bonds by remineralizing resin-dentin interfaces. The GTR medium consists of a Portland cement/simulated body fluid that includes polyacrylic acid and polyvinylphosphonic acid biomimetic analogs for amorphous calcium phosphate dimension regulation and collagen targeting. Both interfibrillar and intrafibrillar apatites became readily discernible within the adhesive-bonded dentin after 2-4 months. Amorphous nanoprecursors created by GTR also penetrated the adhesive resin matrix to create nanocomposites. We anticipate GTR to be the starting point for more sophisticated strategies in extending the longevity of resin-dentin bonds.
Towards a model of non-equilibrium binding of a metal ion in a biological system
Authors: Beardmore James , Exley Christopher 
Published: July 2019

AbstractWe have used a systems biology approach to address the hitherto insoluble problem of the quantitative analysis of non-equilibrium binding of aqueous metal ions by competitive ligands in heterogeneous media. To-date, the relative proportions of different metal complexes in aqueous media have only been modelled at chemical equilibrium and there are no quantitative analyses of the approach to equilibrium1. While these models have improved our understanding of how metals are used in biological systems they cannot account for the influence of kinetic factors in metal binding, transport and fate2. Here we have modelled the binding of aluminium in blood serum by the iron transport protein transferrin (Tf) as it is widely accepted that the biological fate of this non-essential metal is not adequately described by experiments, in vitro and in silico, which have consistently demonstrated that at equilibrium 90% of serum Al(III) is bound by Tf3-5. We have coined this paradox &apos;the blood-aluminium problem&apos;6 and herein applied a systems biology approach which utilised well-found assumptions to pare away the complexities of the problem such that it was defined by a comparatively simple set of computational rules and, importantly, its solution assumed significant predictive capabilities. Here we show that our novel computational model successfully described the binding of Al(III) by Tf both at equilibrium and as equilibrium for AlTf was approached. The model provided an explanation of why the distribution of Al(III) in the body cannot be adequately described by its binding and transport by Tf and it highlighted the significance of kinetic in addition to thermodynamic constraints in defining the fate of metal ions in biological systems. This is the first model of non-equilibrium metal binding in a biological system and it should prove to be a valuable predictive tool in furthering our understanding of the bioinorganic chemistry of metals.
Community dynamics generates complex epidemiology through self-induced amplification and suppression
Authors: Zhao Zhenyuan , Calderon Juan Pablo , Xu Chen , Hui Pak Ming , Johnson Neil 
Published: July 2019

AbstractThe development of quantitative models of outbreaks is key to their eventual control, from human and computer viruses through to social (and antisocial) activities. Standard epidemiological models can reproduce many general features of outbreaks. Unfortunately, the large temporal fluctuations which often dominate real-world data are thought to require more complicated, system-specific models involving super-spreaders, specific social network topologies and rewirings, and birth-death processes. However we show here that these large fluctuations have a generic explanation in terms of underlying community dynamics. Communities increasing (or decreasing) in size, act as instantaneous amplifiers (or suppressors) yielding a complex temporal evolution whose features vary dramatically according to the relative timescales of the community dynamics. We uncover, and provide an analytic theory for, a novel epidemiological phase transition driven by the population&apos;s response to an outbreak. An imminent epidemic will be suppressed if individual communities start to break up more frequently or join together less frequently, but will be amplified if the reverse is true.
Molecular implications of prolonged aggression experience: Th, Dat1, Snca and Bdnf gene expression in the ventral tegmental area of the victorious male mice
Authors: Bondar Natalia P. , Boyarskikh Ul’yana A. , Kovalenko Irina L. , Filipenko Maxim L. , Kudryavtseva Natalia 
Published: July 2019

AbstractTh, Dat1, Snca and Bdnf were the genes whose mRNA levels in the ventral tegmental area of the midbrain were measured in male mice that were victorious in 20 daily agonistic interactions and in a group of such victorious mice that had later not been allowed to fight for 14 days. This experiment demonstrated increased Th, Dat1 and Snca but not Bdnf mRNA levels in the former group as compared to the controls. In the latter group, the expression of the Th and Dat1 genes was still enhanced, while the level of Snca mRNA did not differ from that in the controls. These findings suggest that positive fighting experience enhances the expression of the genes concerned with dopaminergic systems and this enhanced expression is preserved for a long time afterwards. Significant positive correlations were found between the level of aggression and Th and Snca mRNA levels in the winners.
Molecular implications of prolonged aggression experience: Th, Dat1, Snca and Bdnf gene expression in the ventral tegmental area of the victorious male mice
Authors: Bondar N. , Boyarskikh U. , Kovalenko I. , Filipenko M. , Kudryavtseva N. 
Published: July 2019

AbstractTh, Dat1, Snca and Bdnf were the genes whose mRNA levels in the ventral tegmental area of the midbrain were measured in male mice that were victorious in 20 daily agonistic interactions and in a group of such victorious mice that had later not been allowed to fight for 14 days. This experiment demonstrated increased Th, Dat1 and Snca but not Bdnf mRNA levels in the former group as compared to the controls. In the latter group, the expression of the Th and Dat1 genes was still enhanced, while the level of Snca mRNA did not differ from that in the controls. These findings suggest that positive fighting experience enhances the expression of the genes concerned with dopaminergic systems and this enhanced expression is preserved for a long time afterwards. Significant positive correlations were found between the level of aggression and Th and Snca mRNA levels in the winners.
Feeding preferences of Microcerotermes championi (snyder) on different timbers dried at different temperatures under choice and no choice trials
Authors: Rasib Khalid Zamir 
Published: July 2019

AbstractTen species of wood were tested for their natural resistance and to reveal feeding preferences of M. championi. In "no choice" laboratory experiments, Abies pindrow was found highly resistant and Populus euramericana highly palatable. The impact of drying temperature (60°C, 70°C, 80°C, 90°C and 100°C) was studied. The amount of wood consumed in general, increased with increase in drying temperature indicating that heat contributed to the loss of natural resistance components of the woods. When M. championi was given a choice and the woods were offered in combination of two, this termite species repeated its instinct, easily identified the more preferred wood and consumed more of it. Consequently, M. championi showed maximum feeding on P. euramericana and the minimum on A. pindrow and the mean feeding propensity was significantly different (P < 0.0028). Based on the feeding propensity, the woods are arranged in descending order of preference: Populus euramericana > Azadirachta indica > Cedrus deodara > Pinus roxburghii > Morus alba > Tectona grandis > Mangifera indica > Acacia arabica > Thuja occidentalis > Abies pindrow. Although M. championi fed aggressively on P. roxburghii, the wooden blocks had undesirable effect on the survival of the species, manifesting toxic nature of the wood.
Mechanisms linking plant diversity to large herbivore performance
Authors: Wang Ling , Wang Deli , He Zhengbiao , Liu Guofang , Hodgkinson Ken 
Published: July 2019

AbstractThere is established concern that loss of biodiversity will affect ecosystem productivity, nutrient cycling, carbon storage, stability and other properties^1,2^. Interactions between trophic levels are thought to link changes to biodiversity and ecosystem processes^3-6^. However, there is a lack of empirical studies linking plant diversity with altered trophic levels^7,8^, especially for large herbivores, the important but often neglected, controlling trophic level in terrestrial systems. Here we examine responses in performance of the large generalist herbivore to changes in plant diversity, using an indoor cafeteria trial and a field experiment. Our results show that increased plant diversity improves herbivore performance but it is depressed at highest plant diversity levels. We propose the Disturbance Selection Hypothesis for explaining plant diversity effects on primary consumers. Increasing the number of plant species in grassland, increases consumption and enhances nutrient intake (presumably improving animal fitness) by modifying nutrient balance, toxin dilution and taste modulation. High plant diversity simultaneously intensifies animal diet switching frequency, and weakens the herbivore's ability to select food, thereby increasing foraging cost and disturbing the herbivore's selection of forage. Thus, the consequence of plant diversity for large herbivore performance depends on the trade-off between the positive and negative effects. At highest plant diversity the positive effects weaken and negative effects strengthen. We suggest knowledge of the mechanisms is the means for understanding relationships between biodiversity and ecosystem functioning, and the management of large herbivores on rangelands used for conservation and grazing.
Cortical responses reflecting inhibition of return (IOR): a magnetoencephalographic study
Authors: Hashimoto Akiko , Takeshima Yasuyuki , Inui Koji , Kakigi Ryusuke 
Published: July 2019

AbstractInhibition of return (IOR) is a phenomenon whereby the reaction time (RT) to detect a second stimulus (target) presented at the same location as the first stimulus (cue) is longer than when the target is presented at an un-cued location. In the present study, we investigated cortical activities under a standard IOR paradigm by recording visual evoked magnetic fields (VEFs). In Experiment 1, subjects directed their attention to the target at the periphery of the screen and the RT was measured. In Experiment 2, they paid attention to the center of the screen and the RT was not measured. In both experiments, the peak latency of the major deflection of VEFs in the occipito-temporal area was greater for the cued target than un-cued target. This is the first study to report the IOR response of the visual cortex, and our results support the pre-attentive nature of the IOR phenomenon.
Reservoir of Bacterial Exotoxin Genes in the Environment
Authors: Casas Veronica , Magbanua Joseph , Sobrepeña Gerico , Maloy Stanley 
Published: July 2019

AbstractThis is the first report of an environmental reservoir of a bacterial exotoxin gene harbored in an atypical host in the environment. Screening bacterial isolates from the environment via sea-specific PCR identified an isolate with a DNA sequence >95% identical to the Staphylococcus aureus enterotoxin A gene (sea). 16S DNA sequence comparisons identified the environmental isolate as a Pseusodomonad. Laboratory studies confirmed that this Pseudomonad is psychrophilic. The results indicate that the sea gene is present in an alternative bacterial host, providing the first evidence for an environmental reservoir of exotoxin genes in bacteria. Transfer of these genes between phage and alternative bacterial hosts may promote the evolution of novel human diseases.
Oilseed Rape straw for Cultivation of Oyster Mushroom
Authors: Peyvast Gholamali , Nowroozi Ahmad , Olfati Jamal-Ali 
Published: July 2019

AbstractOyster mushroom [Pleurotus ostreatus var. sajor caju (Fr.) Singer] cultivation can play an important role in managing organic waste. It can be cultivated on a wide rang of substrates containing lignin and cellulose. Oyster mushroom was grown on five substrates: Rise straw (Oryza sativa L. var. Alikazemi), Rise straw + Oilseed Rape straw (Brassica napus var. Hyola 401) (75:25 dw /dw), Rise straw + Oilseed Rape straw (50:50 dw /dw), Rise straw + Oilseed Rape straw (25:75 dw /dw) and Oilseed Rape straw alone. Oilseed Rape straw alone and Rise straw + Oilseed Rape straw (25:75 dw /dw) were best for fruit body production of P. ostreatus. Time to fruiting for P. ostreatus was also shorter on Oilseed Rape straw. Protein content of the fruit bodies obtained from Oilseed Rape straw was higher than those from other substrates. Using Oilseed Rape straw as a substrate appears to be suitable for oyster mushroom production.
Caloric restriction causes symmetric cell division and delays aging in Escherichia coli
Authors: Watve Milind , Watve Samit , Belsare Prajakta , Lele Uttara , Bari Snehal , Karande Sarika 
Published: July 2019

AbstractAging is one of the most intriguing processes of biology and despite decades of research, many aspects of aging are poorly understood. Aging is known to occur in bacteria and yeast that divide with morphological asymmetry. Morphologically symmetrically dividing bacteria such as Escherichia coli were assumed not to age until they were shown to divide with functional asymmetry leading to aging and death of some of the cells even in exponentially growing cultures. In asymmetrically dividing E. coli the newly synthesized components are presumed to occupy one pole so that after division one of the daughter cells receives newly synthesized components whereas the other retains the older components. Mathematical models predicted that at the population level, asymmetric growth should result in higher growth rate and symmetric growth in higher growth yield. Therefore, arguably symmetric cell division should be selected in low nutrient environments and asymmetric division in nutrient rich environments. A further prediction was that lower substrate concentrations should strengthen repair mechanisms and suppress aging whereas higher substrate concentrations suppress repair and enhance aging. We show here that E. coli divides more symmetrically under caloric restriction, that both genetic selection and phenotypic plasticity are important determinants of cell division symmetry and also that the proportion of cells that stop dividing and therefore are presumably dead is significantly lower in symmetrically dividing cultures. However, contrary to the prediction, symmetry was not always accompanied by reduced growth rate. These results demonstrate that asymmetry of division in E. coli is not hardwired but responsive to the nutritional environment. This provides a new perspective on why caloric restriction increases lifespan in organisms ranging from microbes to mammals. Symmetry of division may be a mechanism spanning across the width of life forms but regulating aging in different ways in different forms.
Body Fat is Associated with Decreased Endocrine and Cognitive Resilience to Acute Emotional Stress
Authors: Mujica-Parodi Lilianne , Renelique Rudolph , Taylor Marcus 
Published: July 2019

Abstract
*Objective:*
Cortisol is elevated both in individuals with increased emotional stress as well as with higher percentages of body fat. Cortisol is also known to affect cognitive performance, particularly spatial processing, selective attention, and working memory. We hypothesized that increased body fat might therefore be associated with decreased performance on a spatial processing task, in response to an acute real-world stressor. *Design:* We tested two separate samples of subjects undergoing their first (tandem) skydive. In the first sample (N=78), subjects were tested for salivary cortisol and state-anxiety (Spielberger State Anxiety Scale) during the plane's fifteen-minute ascent to altitude in immediate anticipation of the jump. In a second sample (N=20), subjects were tested for salivary cortisol, as well as cardiac variables (heart rate, autonomic regulation via heart rate variability) and performance on a cognitive task of spatial processing, selective attention, and working memory.

*Results:*
In response to the skydive, individuals with greater body fat percentages showed significantly increased reactivity for both cortisol (on both samples) and cognition, including decreased accuracy of our task of spatial processing, selective attention, and working memory. These cognitive effects were restricted to the stress response and were not found under baseline conditions. There were no body fat interactions with cardiac changes in response to the stressor, suggesting that the cognitive effects were specifically hormone-mediated rather than secondary to general activation of the autonomic nervous system.

*Conclusions:*
Our results indicate that, under real-world stress, increased body fat may be associated with endocrine stress-vulnerability, with consequences for deleterious cognitive performance.