bluuebunny/crossref_metadata_2025_split huggingface dataset:
Roles of the mitochondrial Na+-Ca2+ exchanger, NCLX, in B lymphocyte chemotaxis
Authors: Kim Bongju , Takeuchi Ayako , Hikida Masaki , Matsuoka Satoshi 
Published: June 2016

AbstractLymphocyte chemotaxis plays important roles in immunological reactions, although the mechanism of its regulation is still unclear. We found that the cytosolic Na+-dependent mitochondrial Ca2+ efflux transporter, NCLX, regulates B lymphocyte chemotaxis. Inhibiting or silencing NCLX in A20 and DT40 B lymphocytes markedly increased random migration and suppressed the chemotactic response to CXCL12. In contrast to control cells, cytosolic Ca2+ was higher and was not increased further by CXCL12 in NCLX-knockdown A20 B lymphocytes. Chelating intracellular Ca2+ with BAPTA-AM disturbed CXCL12-induced chemotaxis, suggesting that modulation of cytosolic Ca2+ via NCLX, and thereby Rac1 activation and F-actin polymerization, is essential for B lymphocyte motility and chemotaxis. Mitochondrial polarization, which is necessary for directional movement, was unaltered in NCLX-knockdown cells, although CXCL12 application failed to induce enhancement of mitochondrial polarization, in contrast to control cells. Mouse spleen B lymphocytes were similar to the cell lines, in that pharmacological inhibition of NCLX by CGP-37157 diminished CXCL12-induced chemotaxis. Unexpectedly, spleen T lymphocyte chemotaxis was unaffected by CGP-37157 treatment, indicating that NCLX-mediated regulation of chemotaxis is B lymphocyte-specific, and mitochondria-endoplasmic reticulum Ca2+ dynamics are more important in B lymphocytes than in T lymphocytes. We conclude that NCLX is pivotal for B lymphocyte motility and chemotaxis.
Long-term survival in permanent middle cerebral artery occlusion: a model of malignant stroke in rats
Authors: Shanbhag Nagesh C. , Henning Robert H. , Schilling Lothar 
Published: June 2016

AbstractOcclusion of the middle cerebral artery (MCA) by an intraluminal filament is widely used to study focal brain ischemia in male Sprague-Dawley rats. However, permanent occlusion goes along with a high fatality. To overcome this drawback we designed a new filament carrying a bowling pin-shaped tip (BP-tip) and compared this with three conventionally tipped filaments. Follow-up periods were 24 h (all groups) and 72 and 120 h in BP-tip group. Ischemic damage and swelling were quantified using silver nitrate staining. Collateral flow via the posterior cerebral artery (PCA) was assessed using selective dye perfusion of the internal carotid artery. Despite a comparable decrease of brain perfusion in all groups, ischemic damage was significantly smaller in BP-tips (p < 0.05). Moreover, BP-tip significantly reduced mortality from 60% to 12.5% and widely spared the occipital region and hypothalamus from ischemic damage. Conventional but not BP-tip filaments induced vascular distortion, measured as gross displacement of the MCA origin, which correlated with occipital infarction size. Accordingly, BP-tip occluded rats showed a significantly better collateral filling of the PCA territory. Ischemic volume significantly increased in BP-tip occlusion at 72 h follow-up. BP-tip filaments offer superior survival in permanent MCA occlusion, while mimicking the course of a malignant stroke in patients.
Construction and application of a co-expression network in Mycobacterium tuberculosis
Authors: Jiang Jun , Sun Xian , Wu Wei , Li Li , Wu Hai , Zhang Lu , Yu Guohua , Li Yao 
Published: June 2016

AbstractBecause of its high pathogenicity and infectivity, tuberculosis is a serious threat to human health. Some information about the functions of the genes in Mycobacterium tuberculosis genome was currently available, but it was not enough to explore transcriptional regulatory mechanisms. Here, we applied the WGCNA (Weighted Gene Correlation Network Analysis) algorithm to mine pooled microarray datasets for the M. tuberculosis H37Rv strain. We constructed a co-expression network that was subdivided into 78 co-expression gene modules. The different response to two kinds of vitro models (a constant 0.2% oxygen hypoxia model and a Wayne model) were explained based on these modules. We identified potential transcription factors based on high Pearson’s correlation coefficients between the modules and genes. Three modules that may be associated with hypoxic stimulation were identified, and their potential transcription factors were predicted. In the validation experiment, we determined the expression levels of genes in the modules under hypoxic condition and under overexpression of potential transcription factors (Rv0081, furA (Rv1909c), Rv0324, Rv3334, and Rv3833). The experimental results showed that the three identified modules related to hypoxia and that the overexpression of transcription factors could significantly change the expression levels of genes in the corresponding modules.
Defining and quantifying the resilience of responses to disturbance: a conceptual and modelling approach from soil science
Authors: Todman L. C. , Fraser F. C. , Corstanje R. , Deeks L. K. , Harris J. A. , Pawlett M. , Ritz K. , Whitmore A. P. 
Published: June 2016

AbstractThere are several conceptual definitions of resilience pertaining to environmental systems and, even if resilience is clearly defined in a particular context, it is challenging to quantify. We identify four characteristics of the response of a system function to disturbance that relate to “resilience”: (1) degree of return of the function to a reference level; (2) time taken to reach a new quasi-stable state; (3) rate (i.e. gradient) at which the function reaches the new state; (4) cumulative magnitude of the function (i.e. area under the curve) before a new state is reached. We develop metrics to quantify these characteristics based on an analogy with a mechanical spring and damper system. Using the example of the response of a soil function (respiration) to disturbance, we demonstrate that these metrics effectively discriminate key features of the dynamic response. Although any one of these characteristics could define resilience, each may lead to different insights and conclusions. The salient properties of a resilient response must thus be identified for different contexts. Because the temporal resolution of data affects the accurate determination of these metrics, we recommend that at least twelve measurements are made over the temporal range for which the response is expected.
Random-phase metasurfaces at optical wavelengths
Authors: Pors Anders , Ding Fei , Chen Yiting , Radko Ilya P. , Bozhevolnyi Sergey I. 
Published: June 2016

AbstractRandom-phase metasurfaces, in which the constituents scatter light with random phases, have the property that an incident plane wave will diffusely scatter, hereby leading to a complex far-field response that is most suitably described by statistical means. In this work, we present and exemplify the statistical description of the far-field response, particularly highlighting how the response for polarised and unpolarised light might be alike or different depending on the correlation of scattering phases for two orthogonal polarisations. By utilizing gap plasmon-based metasurfaces, consisting of an optically thick gold film overlaid by a subwavelength thin glass spacer and an array of gold nanobricks, we design and realize random-phase metasurfaces at a wavelength of 800 nm. Optical characterisation of the fabricated samples convincingly demonstrates the diffuse scattering of reflected light, with statistics obeying the theoretical predictions. We foresee the use of random-phase metasurfaces for camouflage applications and as high-quality reference structures in dark-field microscopy, while the control of the statistics for polarised and unpolarised light might find usage in security applications. Finally, by incorporating a certain correlation between scattering by neighbouring metasurface constituents new types of functionalities can be realised, such as a Lambertian reflector.
The role of the residence-effect on the outcome of intergroup encounters in Verreaux’s sifakas
Authors: Koch Flávia , Signer Johannes , Kappeler Peter M. , Fichtel Claudia 
Published: June 2016

AbstractIntergroup competition has an important impact on the survival and fitness of individuals in group-living species. However, factors influencing the probability of winning an encounter are not fully understood. We studied the influence of numerical advantage and location of the encounter on the chances of winning in eight neighboring groups of Verreaux’s sifakas (Propithecus verreauxi), in Kirindy Forest, western Madagascar. Intergroup encounters were inferred from spatial data collected via GPS loggers over a period of two years. Location, i.e., the proximity to the respective core area, rather than the numerical advantage of a group in a given encounter, influenced the probability of winning. Accordingly, the high value that resident groups attribute to exclusive and intensively used areas increased their motivation in defending these locations against intruders. Moreover, losers used the encounter area less often than winners within a month after the encounter, suggesting that losing also entails long-term costs. Thus, our results suggest that in gregarious animals the particular circumstances of each encounter, such as the location, can outweigh group characteristics and predict the chances of winning an intergroup encounter.
Multiscale conformal pattern transfer
Authors: Lodewijks Kristof , Miljkovic Vladimir , Massiot Inès , Mekonnen Addis , Verre Ruggero , Olsson Eva , Dmitriev Alexandre 
Published: June 2016

AbstractWe demonstrate a method for seamless transfer from a parent flat substrate of basically any lithographic top-down or bottom-up pattern onto essentially any kind of surface. The nano- or microscale patterns, spanning macroscopic surface areas, can be transferred with high conformity onto a large variety of surfaces when such patterns are produced on a thin carbon film, grown on top of a sacrificial layer. The latter allows lifting the patterns from the flat parent substrate onto a water-air interface to be picked up by the host surface of choice. We illustrate the power of this technique by functionalizing broad range of materials including glass, plastics, metals, rough semiconductors and polymers, highlighting the potential applications in in situ colorimetry of the chemistry of materials, anti-counterfeit technologies, biomolecular and biomedical studies, light-matter interactions at the nanoscale, conformal photovoltaics and flexible electronics.
Serum Uric Acid Levels were Dynamically Coupled with Hemoglobin A1c in the Development of Type 2 Diabetes
Authors: Wei Fengjiang , Chang Baocheng , Yang Xilin , Wang Yaogang , Chen Liming , Li Wei-Dong 
Published: June 2016

AbstractThe aim of the study was to decipher the relationship between serum uric acid (SUA) and glycated hemoglobin A1c (HbA1c) or fasting plasma glucose (FPG) in both type 2 diabetes mellitus (T2DM) patients and normal subjects. A total of 2,250 unrelated T2DM patients and 4,420 Han Chinese subjects from a physical examination population were recruited for this study. In T2DM patients SUA levels were negatively correlated with HbA1c (rs = −0.109, P = 0.000) and 2 h plasma glucose levels (rs = −0.178, P = 0.000). In the physical examination population, SUA levels were inversely correlated with HbA1c (rs = −0.175, P = 0.000) and FPG (rs = −0.131, P = 0.009) in T2DM patients but positively correlated with HbA1c (rs = 0.040, P = 0.012) and FPG (rs = 0.084, P = 0.000) in normal-glucose subjects. Multivariate analyses showed that HbA1c was significantly negatively associated with HUA both in T2DM patients (OR = 0.872, 95% CI: 0.790~0.963) and in the physical examination T2DM patients (OR = 0.722, 95% CI: 0.539~0.968). Genetic association studies in T2DM patients showed that alleles of two glucose-uric acid transporter genes, ABCG2 and SLC2A9 were significantly associated with SUA levels (P < 0.05). SUA level is inversely correlated with HbA1c in T2DM patients but positively correlated with HbA1c in normal-glucose subjects. The reverse transporting of uric acid and glucose in renal tubules might be accounted for these associations.
Structural insights of a hormone sensitive lipase homologue Est22
Authors: Huang Jing , Huo Ying-Yi , Ji Rui , Kuang Siyun , Ji Chaoneng , Xu Xue-Wei , Li Jixi 
Published: June 2016

AbstractHormone sensitive lipase (HSL) catalyzes the hydrolysis of triacylglycerols into fatty acids and glycerol, thus playing key roles in energy homeostasis. However, the application of HSL serving as a pharmaceutical target and an industrial biocatalyst is largely hampered due to the lack of high-resolution structural information. Here we report biochemical properties and crystal structures of a novel HSL homologue esterase Est22 from a deep-sea metagenomic library. Est22 prefers short acyl chain esters and has a very high activity with substrate p-nitrophenyl butyrate. The crystal structures of wild type and mutated Est22 with its product p-nitrophenol are solved with resolutions ranging from 1.4 Å to 2.43 Å. The Est22 exhibits a α/β-hydrolase fold consisting with a catalytic domain and a substrate-recognizing cap domain. Residues Ser188, Asp287, and His317 comprise the catalytic triad in the catalytic domain. The p-nitrophenol molecule occupies the substrate binding pocket and forms hydrogen bonds with adjacent residues Gly108, Gly109, and Gly189. Est22 exhibits a dimeric form in solution, whereas mutants D287A and H317A change to polymeric form, which totally abolished its enzymatic activities. Our study provides insights into the catalytic mechanism of HSL family esterase and facilitates the understanding for further industrial and biotechnological applications of esterases.
Paradoxical augmented relapse in alcohol-dependent rats during deep-brain stimulation in the nucleus accumbens
Authors: Hadar R , Vengeliene V , Barroeta Hlusicke E , Canals S , Noori H R , Wieske F , Rummel J , Harnack D , Heinz A , Spanagel R , Winter C 
Published: June 2016

AbstractCase reports indicate that deep-brain stimulation in the nucleus accumbens may be beneficial to alcohol-dependent patients. The lack of clinical trials and our limited knowledge of deep-brain stimulation call for translational experiments to validate these reports. To mimic the human situation, we used a chronic-continuous brain-stimulation paradigm targeting the nucleus accumbens and other brain sites in alcohol-dependent rats. To determine the network effects of deep-brain stimulation in alcohol-dependent rats, we combined electrical stimulation of the nucleus accumbens with functional magnetic resonance imaging (fMRI), and studied neurotransmitter levels in nucleus accumbens-stimulated versus sham-stimulated rats. Surprisingly, we report here that electrical stimulation of the nucleus accumbens led to augmented relapse behavior in alcohol-dependent rats. Our associated fMRI data revealed some activated areas, including the medial prefrontal cortex and caudate putamen. However, when we applied stimulation to these areas, relapse behavior was not affected, confirming that the nucleus accumbens is critical for generating this paradoxical effect. Neurochemical analysis of the major activated brain sites of the network revealed that the effect of stimulation may depend on accumbal dopamine levels. This was supported by the finding that brain-stimulation-treated rats exhibited augmented alcohol-induced dopamine release compared with sham-stimulated animals. Our data suggest that deep-brain stimulation in the nucleus accumbens enhances alcohol-liking probably via augmented dopamine release and can thereby promote relapse.
Nucleus accumbens deep-brain stimulation efficacy in ACTH-pretreated rats: alterations in mitochondrial function relate to antidepressant-like effects
Authors: Kim Y , McGee S , Czeczor J K , Walker A J , Kale R P , Kouzani A Z , Walder K , Berk M , Tye S J 
Published: June 2016

AbstractMitochondrial dysfunction has a critical role in the pathophysiology of mood disorders and treatment response. To investigate this, we established an animal model exhibiting a state of antidepressant treatment resistance in male Wistar rats using 21 days of adrenocorticotropic hormone (ACTH) administration (100 μg per day). First, the effect of ACTH treatment on the efficacy of imipramine (10 mg kg−1) was investigated alongside its effect on the prefrontal cortex (PFC) mitochondrial function. Second, we examined the mood-regulatory actions of chronic (7 day) high-frequency nucleus accumbens (NAc) deep-brain stimulation (DBS; 130 Hz, 100 μA, 90 μS) and concomitant PFC mitochondrial function. Antidepressant-like responses were assessed in the open field test (OFT) and forced swim test (FST) for both conditions. ACTH pretreatment prevented imipramine-mediated improvement in mobility during the FST (P<0.05). NAc DBS effectively improved FST mobility in ACTH-treated animals (P<0.05). No improvement in mobility was observed for sham control animals (P>0.05). Analyses of PFC mitochondrial function revealed that ACTH-treated animals had decreased capacity for adenosine triphosphate production compared with controls. In contrast, ACTH animals following NAc DBS demonstrated greater mitochondrial function relative to controls. Interestingly, a proportion (30%) of the ACTH-treated animals exhibited heightened locomotor activity in the OFT and exaggerated escape behaviors during the FST, together with general hyperactivity in their home-cage settings. More importantly, the induction of this mania-like phenotype was accompanied by overcompensative increased mitochondrial respiration. Manifestation of a DBS-induced mania-like phenotype in imipramine-resistant animals highlights the potential use of this model in elucidating mechanisms of mood dysregulation.
Micro‐Doppler‐based in‐home aided and unaided walking recognition with multiple radar and sonar systems
Authors: Gurbuz Sevgi Zubeyde , Clemente Carmine , Balleri Alessio , Soraghan John J. 
Published: June 2016

The potential for using micro‐Doppler signatures as a basis for distinguishing between aided and unaided gaits is considered in this study for the purpose of characterising normal elderly gait and assessment of patient recovery. In particular, five different classes of mobility are considered: normal unaided walking, walking with a limp, walking using a cane or tripod, walking with a walker, and using a wheelchair. This presents a challenging classification problem as the differences in micro‐Doppler for these activities can be quite slight. Within this context, the performance of four different radar and sonar systems – a 40 kHz sonar, a 5.8 GHz wireless pulsed Doppler radar mote, a 10 GHz X‐band continuous wave (CW) radar, and a 24 GHz CW radar – is evaluated using a broad range of features. Performance improvements using feature selection is addressed as well as the impact on performance of sensor placement and potential occlusion due to household objects. Results show that nearly 80% correct classification can be achieved with 10 s observations from the 24 GHz CW radar, whereas 86% performance can be achieved with 5 s observations of sonar.
Temperature effect on morphology and electrochemical properties of nanostructured ZnO as anode for lithium ion batteries
Authors: Zhang Lifeng , He Wenjie , Liu Yi , Zheng Peng , Yuan Xiaoyan , Guo Shouwu 
Published: June 2016

Nanostructured zinc oxide (ZnO) with different morphology has been synthesised by a facile hydrothermal method combining calcination procedure at different temperatures. The effect of calcination temperature on the morphology and electrochemical properties of as‐synthesised ZnO is investigated. X‐ray diffraction, scanning electron microscopy and transmission electron microscopy were applied to characterise the phase composition and microstructure of the synthesised samples. The electrochemical tests of as‐synthesised ZnO as an anode material for lithium ion batteries (LIBs) reveal that ZnO nanoparticles prepared at 700°C deliver the largest capacity of 1815.8 mAh g−1, while cabbage‐like ZnO nanosheets prepared at lower temperatures display better cycling stability. It is believed that the diverse morphologies of nanostructured ZnO crucially affect their electrochemical properties as an anode material for LIBs.
Residency and Movement of Juvenile Chinook Salmon at Multiple Spatial Scales in a Tidal Marsh of the Columbia River Estuary
Authors: McNatt Regan A. , Bottom Daniel L. , Hinton Susan A. 
Published: June 2016

AbstractUse of the Columbia River estuary by juvenile Pacific salmon Oncorhynchus spp. is garnering more attention as managers look to improve salmon survival through estuary restoration. Studies have shown that juvenile salmon are abundant in shallow‐water habitats within the Columbia River estuary, but information on how juveniles exploit specific estuarine habitats is lacking. We used a combination of physical marks and PIT tag technology to record residence time, movement, and growth of juvenile Chinook Salmon O. tshawytscha, particularly subyearlings, within an emergent marsh of the Columbia River estuary during 2005, 2006, and 2008. We documented marsh‐scale residency and movement within the marsh complex and channel‐scale residency and movement within two small secondary channels. Many juvenile Chinook Salmon remained in the marsh for 2–4 weeks and increased in FL by 10–20 mm, with an average growth rate of 0.53 mm/d. Chinook Salmon entered secondary channels most frequently in late afternoon and occasionally did so against the tide. Our results indicate that subyearling Chinook Salmon take advantage of shallow estuarine habitat in the Columbia River to a greater extent than previously documented.Received January 8, 2016; accepted March 21, 2016 Published online June 21, 2016
Emergence of microbial diversity due to cross-feeding interactions in a spatial model of gut microbial metabolism
Authors: Van Hoek Milan JA , Merks Roeland MH 
Published: June 2016

AbstractBackgroundThe human gut contains approximately 1014bacteria, belonging to hundreds of different species. Together, these microbial species form a complex food web that can break down food sources that our own digestive enzymes cannot handle, including complex polysaccharides, producing short chain fatty acids and additional metabolites,e.g., vitamin K. The diversity of microbial diversity is important for colonic health: Changes in the composition of the microbiota have been associated with inflammatory bowel disease, diabetes, obestity and Crohn’s disease, and make the microbiota more vulnerable to infestation by harmful species,e.g., Clostridium difficile. To get a grip on the controlling factors of microbial diversity in the gut, we here propose a multi-scale, spatiotemporal dynamic flux-balance analysis model to study the emergence of metabolic diversity in a spatial gut-like, tubular environment. The model features genome-scale metabolic models of microbial populations, resource sharing via extracellular metabolites, and spatial population dynamics and evolution.ResultsIn this model, cross-feeding interactions emerge readily, despite the species’ ability to metabolize sugars autonomously. Interestingly, the community requires cross-feeding for producing a realistic set of short-chain fatty acids from an input of glucose, If we let the composition of the microbial subpopulations change during invasion of adjacent space, a complex and stratifed microbiota evolves, with subspecies specializing on cross-feeding interactions via a mechanism of compensated trait loss. The microbial diversity and stratification collapse if the flux through the gut is enhanced to mimic diarrhea.ConclusionsIn conclusion, thisin silicomodel is a helpful tool in systems biology to predict and explain the controlling factors of microbial diversity in the gut. It can be extended to include,e.g., complex food source, and host-microbiota interactions via the gut wall.