bluuebunny/crossref_metadata_2025 huggingface dataset:
Cooling a mechanical resonator with nitrogen-vacancy centres using a room temperature excited state spin–strain interaction
Authors: MacQuarrie E. R. , Otten M. , Gray S. K. , Fuchs G. D.
Published: February 2017

Cooling a mechanical resonator mode to a sub-thermal state has been a long-standing challenge in physics. This pursuit has recently found traction in the field of optomechanics in which a mechanical mode is coupled to an optical cavity. An alternate method is to couple the resonator to a well-controlled two-level system. Here we propose a protocol to dissipatively cool a room temperature mechanical resonator using a nitrogen-vacancy centre ensemble. The spin ensemble is coupled to the resonator through its orbitally-averaged excited state, which has a spin–strain interaction that has not been previously studied. We experimentally demonstrate that the spin–strain coupling in the excited state is 13.5±0.5 times stronger than the ground state spin–strain coupling. We then theoretically show that this interaction, combined with a high-density spin ensemble, enables the cooling of a mechanical resonator from room temperature to a fraction of its thermal phonon occupancy.
Killing by Type VI secretion drives genetic phase separation and correlates with increased cooperation
Authors: McNally Luke , Bernardy Eryn , Thomas Jacob , Kalziqi Arben , Pentz Jennifer , Brown Sam P. , Hammer Brian K. , Yunker Peter J. , Ratcliff William C.
Published: February 2017

By nature of their small size, dense growth and frequent need for extracellular metabolism, microbes face persistent public goods dilemmas. Genetic assortment is the only general solution stabilizing cooperation, but all known mechanisms structuring microbial populations depend on the availability of free space, an often unrealistic constraint. Here we describe a class of self-organization that operates within densely packed bacterial populations. Through mathematical modelling and experiments withVibrio cholerae,we show how killing adjacent competitors via the Type VI secretion system (T6SS) precipitates phase separation via the ‘Model A’ universality class of order-disorder transition mediated by killing. We mathematically demonstrate that T6SS-mediated killing should favour the evolution of public goods cooperation, and empirically support this prediction using a phylogenetic comparative analysis. This work illustrates the twin role played by the T6SS, dealing death to local competitors while simultaneously creating conditions potentially favouring the evolution of cooperation with kin.
Foxn1-β5t transcriptional axis controls CD8+ T-cell production in the thymus
Authors: Uddin Muhammad Myn , Ohigashi Izumi , Motosugi Ryo , Nakayama Tomomi , Sakata Mie , Hamazaki Jun , Nishito Yasumasa , Rode Immanuel , Tanaka Keiji , Takemoto Tatsuya , Murata Shigeo , Takahama Yousuke
Published: February 2017

The thymus is an organ that produces functionally competent T cells that protect us from pathogens and malignancies. Foxn1 is a transcription factor that is essential for thymus organogenesis; however, the direct target for Foxn1 to actuate thymic T-cell production is unknown. Here we show that a Foxn1-binding cis-regulatory element promotes the transcription of β5t, which has an essential role in cortical thymic epithelial cells to induce positive selection of functionally competent CD8+ T cells. A point mutation in this genome element results in a defect in β5t expression and CD8+ T-cell production in mice. The results reveal a Foxn1-β5t transcriptional axis that governs CD8+ T-cell production in the thymus.
Innovation and constraint leading to complex multicellularity in the Ascomycota
Authors: Nguyen Tu Anh , Cissé Ousmane H. , Yun Wong Jie , Zheng Peng , Hewitt David , Nowrousian Minou , Stajich Jason E. , Jedd Gregory
Published: February 2017

The advent of complex multicellularity (CM) was a pivotal event in the evolution of animals, plants and fungi. In the fungal Ascomycota, CM is based on hyphal filaments and arose in the Pezizomycotina. The genus Neolecta defines an enigma: phylogenetically placed in a related group containing mostly yeasts, Neolecta nevertheless possesses Pezizomycotina-like CM. Here we sequence the Neolecta irregularis genome and identify CM-associated functions by searching for genes conserved in Neolecta and the Pezizomycotina, which are absent or divergent in budding or fission yeasts. This group of 1,050 genes is enriched for functions related to diverse endomembrane systems and their organization. Remarkably, most show evidence for divergence in both yeasts. Using functional genomics, we identify new genes involved in fungal complexification. Together, these data show that rudimentary multicellularity is deeply rooted in the Ascomycota. Extensive parallel gene divergence during simplification and constraint leading to CM suggest a deterministic process where shared modes of cellular organization select for similarly configured organelle- and transport-related machineries.
Redox preconditioning deep cratonic lithosphere for kimberlite genesis – evidence from the central Slave Craton
Authors: Yaxley G. M. , Berry A. J. , Rosenthal A. , Woodland A. B. , Paterson D.
Published: February 2017

We present the first oxygen fugacity (fO2) profile through the cratonic lithospheric mantle under the Panda kimberlite (Ekati Diamond Mine) in the Lac de Gras kimberlite field, central Slave Craton, northern Canada. Combining this data with new and existing data from garnet peridotite xenoliths from an almost coeval kimberlite (A154-N) at the nearby Diavik Diamond Mine demonstrates that the oxygen fugacity of the Slave cratonic mantle varies by several orders of magnitude as a function of depth and over short lateral distances. The lower part of the diamond-bearing Slave lithosphere (>120–130 km deep) has been oxidized by up to 4 log units in fO2, and this is clearly linked to metasomatic enrichment. Such coupled enrichment and oxidation was likely caused by infiltrating carbonate-bearing, hydrous, silicate melts in the presence of diamond, a process proposed to be critical for “pre-conditioning” deep lithospheric mantle and rendering it suitable for later generation of kimberlites and other SiO2-undersaturated magmas.
Microbial shifts in the porcine distal gut in response to diets supplemented with Enterococcus Faecalis as alternatives to antibiotics
Authors: Li Pinghua , Niu Qing , Wei Qingtian , Zhang Yeqiu , Ma Xiang , Kim Sung Woo , Lin Mingxin , Huang Ruihua
Published: February 2017

Gut microbiota plays an important role in host health and nutrient digestion of animals. Probiotics have become one of effective alternatives to antibiotics enhancing animal health and performance through modulating gut microbiota. Previously, our research demonstrated that dietary Enterococcus Faecalis UC-100 substituting antibiotics enhanced growth and health of weaned pigs. To investigate the alterations of microbiota in the distal gut of pigs fed E. faecalis UC-100 substituting antibiotics, this study assessed fecal microbiota in pigs from different dietary treatments: the basal diet group, the E. faecalis group, and the antibiotic group on d 0, 14, and 28 of feeding through 16 S rRNA sequencing. Twenty-one phyla and 137 genera were shared by all pigs, whereas 12 genera were uniquely identified in the E. faecalis group on d 14 and 28. Bacterial abundance and diversity in the E. faecalis group, bacterial diversity in the antibiotic group, especially abundances of Fibrobacteres phylum and 12 genera in the E. faecalis group and antibiotics group were lower than that in the basal diet group on d 28. These results showed that microbial shifts in the porcine gut in response to diets containing E. faecalis were similar to the response to which containing antibiotics.
Extinctions, genetic erosion and conservation options for the black rhinoceros (Diceros bicornis)
Authors: Moodley Yoshan , Russo Isa-Rita M. , Dalton Desiré L. , Kotzé Antoinette , Muya Shadrack , Haubensak Patricia , Bálint Boglárka , Munimanda Gopi K. , Deimel Caroline , Setzer Andrea , Dicks Kara , Herzig-Straschil Barbara , Kalthoff Daniela C. , Siegismund Hans R. , Robovský Jan , O’Donoghue Paul , Bruford Michael W.
Published: February 2017

The black rhinoceros is again on the verge of extinction due to unsustainable poaching in its native range. Despite a wide historic distribution, the black rhinoceros was traditionally thought of as depauperate in genetic variation, and with very little known about its evolutionary history. This knowledge gap has hampered conservation efforts because hunting has dramatically reduced the species’ once continuous distribution, leaving five surviving gene pools of unknown genetic affinity. Here we examined the range-wide genetic structure of historic and modern populations using the largest and most geographically representative sample of black rhinoceroses ever assembled. Using both mitochondrial and nuclear datasets, we described a staggering loss of 69% of the species’ mitochondrial genetic variation, including the most ancestral lineages that are now absent from modern populations. Genetically unique populations in countries such as Nigeria, Cameroon, Chad, Eritrea, Ethiopia, Somalia, Mozambique, Malawi and Angola no longer exist. We found that the historic range of the West African subspecies (D. b. longipes), declared extinct in 2011, extends into southern Kenya, where a handful of individuals survive in the Masai Mara. We also identify conservation units that will help maintain evolutionary potential. Our results suggest a complete re-evaluation of current conservation management paradigms for the black rhinoceros.
AMPK regulates lipid accumulation in skeletal muscle cells through FTO-dependent demethylation of N6-methyladenosine
Authors: Wu Weiche , Feng Jie , Jiang Denghu , Zhou Xihong , Jiang Qin , Cai Min , Wang Xinxia , Shan Tizhong , Wang Yizhen
Published: February 2017

Skeletal muscle plays important roles in whole-body energy homeostasis. Excessive skeletal muscle lipid accumulation is associated with some metabolic diseases such as obesity and Type 2 Diabetes. The energy sensor AMPK (AMP-activated protein kinase) is a key regulator of skeletal muscle lipid metabolism, but the precise regulatory mechanism remains to be elucidated. Here, we provide a novel mechanism by which AMPK regulates skeletal muscle lipid accumulation through fat mass and obesity-associated protein (FTO)-dependent demethylation ofN6-methyladenosine (m6A). We confirmed an inverse correlation between AMPK and skeletal muscle lipid content. Moreover, inhibition of AMPK enhanced lipid accumulation, while activation of AMPK reduced lipid accumulation in skeletal muscle cells. Notably, we found that mRNA m6A methylation levels were inversely correlated with lipid content in skeletal muscle. Furthermore, AMPK positively regulated the m6A methylation levels of mRNA, which could negatively regulate lipid accumulation in C2C12. At the molecular level, we demonstrated that AMPK regulated lipid accumulation in skeletal muscle cells by regulating FTO expression and FTO-dependent demethylation of m6A. Together, these results provide a novel regulatory mechanism of AMPK on lipid metabolism in skeletal muscle cells and suggest the possibility of controlling skeletal muscle lipid deposition by targeting AMPK or using m6A related drugs.
Schottky barrier at graphene/metal oxide interfaces: insight from first-principles calculations
Authors: Cheng Kai , Han Nannan , Su Yan , Zhang Junfeng , Zhao Jijun
Published: February 2017

Anode materials play an important role in determining the performance of lithium ion batteries. In experiment, graphene (GR)/metal oxide (MO) composites possess excellent electrochemical properties and are promising anode materials. Here we perform density functional theory calculations to explore the interfacial interaction between GR and MO. Our result reveals generally weak physical interactions between GR and several MOs (including Cu2O, NiO). The Schottky barrier height (SBH) in these metal/semiconductor heterostructures are computed using the macroscopically averaged electrostatic potential method, and the role of interfacial dipole is discussed. The calculated SBHs below 1 eV suggest low contact resistance; thus these GR/MO composites are favorable anode materials for better lithium ion batteries.
New Insights on Signal Propagation by Sensory Rhodopsin II/Transducer Complex
Authors: Ishchenko A. , Round E. , Borshchevskiy V. , Grudinin S. , Gushchin I. , Klare J. P. , Remeeva A. , Polovinkin V. , Utrobin P. , Balandin T. , Engelhard M. , Büldt G. , Gordeliy V.
Published: February 2017

The complex of two membrane proteins, sensory rhodopsin II (NpSRII) with its cognate transducer (NpHtrII), mediates negative phototaxis in halobacteria N. pharaonis. Upon light activation NpSRII triggers a signal transduction chain homologous to the two-component system in eubacterial chemotaxis. Here we report on crystal structures of the ground and active M-state of the complex in the space group I212121. We demonstrate that the relative orientation of symmetrical parts of the dimer is parallel (“U”-shaped) contrary to the gusset-like (“V”-shaped) form of the previously reported structures of the NpSRII/NpHtrII complex in the space group P21212, although the structures of the monomers taken individually are nearly the same. Computer modeling of the HAMP domain in the obtained “V”- and “U”-shaped structures revealed that only the “U”-shaped conformation allows for tight interactions of the receptor with the HAMP domain. This is in line with existing data and supports biological relevance of the “U” shape in the ground state. We suggest that the “V”-shaped structure may correspond to the active state of the complex and transition from the “U” to the “V”-shape of the receptor-transducer complex can be involved in signal transduction from the receptor to the signaling domain of NpHtrII.
Paeoniflorin Ameliorates Experimental Autoimmune Encephalomyelitis via Inhibition of Dendritic Cell Function and Th17 Cell Differentiation
Authors: Zhang Han , Qi Yuanyuan , Yuan Yuanyang , Cai Li , Xu Haiyan , Zhang Lili , Su Bing , Nie Hong
Published: February 2017

Paeoniflorin (PF) is a monoterpene glycoside and exhibits multiple effects, including anti-inflammation and immunoregulation. To date, the effect of PF on multiple sclerosis (MS) has not been investigated. In this study, we investigated the effect of PF in experimental autoimmune encephalomyelitis (EAE), an animal model for MS. After administered with PF, the onset and clinical symptoms of EAE mice were significantly ameliorated, and the number of Th17 cells infiltrated in central nervous system (CNS) and spleen was also dramatically decreased. Instead of inhibiting the differentiation of Th17 cells directly, PF influenced Th17 cells via suppressing the expression of costimulatory molecules and the production of interlukin-6 (IL-6) of dendritic cells (DCs)in vivoandin vitro, which may be attributable to the inhibition of IKK/NF-κB and JNK signaling pathway. When naïve CD4+T cells were co-cultured with PF-treated dendritic cells under Th17-polarizing condition, the percentage of Th17 cells and the phosphorylation of STAT3 were decreased, as well as the mRNA levels of IL-17, RORα, and RORγt. Our study provided insights into the role of PF as a unique therapeutic agent for the treatment of multiple sclerosis and illustrated the underlying mechanism of PF from a new perspective.
Anhedonia to music and mu-opioids: Evidence from the administration of naltrexone
Authors: Mallik Adiel , Chanda Mona Lisa , Levitin Daniel J.
Published: February 2017

Music’s universality and its ability to deeply affect emotions suggest an evolutionary origin. Previous investigators have found that naltrexone (NTX), a μ-opioid antagonist, may induce reversible anhedonia, attenuating both positive and negative emotions. The neurochemical basis of musical experience is not well-understood, and the NTX-induced anhedonia hypothesis has not been tested with music. Accordingly, we administered NTX or placebo on two different days in a double-blind crossover study, and assessed participants’ responses to music using both psychophysiological (objective) and behavioral (subjective) measures. We found that both positive and negative emotions were attenuated. We conclude that endogenous opioids are critical to experiencing both positive and negative emotions in music, and that music uses the same reward pathways as food, drug and sexual pleasure. Our findings add to the growing body of evidence for the evolutionary biological substrates of music.
A combinational CRISPR/Cas9 gene-editing approach can halt HIV replication and prevent viral escape
Authors: Lebbink Robert Jan , de Jong Dorien C. M. , Wolters Femke , Kruse Elisabeth M. , van Ham Petra M. , Wiertz Emmanuel J. H. J. , Nijhuis Monique
Published: February 2017

HIV presents one of the highest evolutionary rates ever detected and combination antiretroviral therapy is needed to overcome the plasticity of the virus population and control viral replication. Conventional treatments lack the ability to clear the latent reservoir, which remains the major obstacle towards a cure. Novel strategies, such as CRISPR/Cas9 gRNA-based genome-editing, can permanently disrupt the HIV genome. However, HIV genome-editing may accelerate viral escape, questioning the feasibility of the approach. Here, we demonstrate that CRISPR/Cas9 targeting of single HIV loci, only partially inhibits HIV replication and facilitates rapid viral escape at the target site. A combinatorial approach of two strong gRNAs targeting different regions of the HIV genome can completely abrogate viral replication and prevent viral escape. Our data shows that the accelerating effect of gene-editing on viral escape can be overcome and as such gene-editing may provide a future alternative for control of HIV-infection.
Spatial variation and inconsistency between estimates of onset of muscle activation from EMG and ultrasound
Authors: Dieterich Angela V. , Botter Alberto , Vieira Taian Martins , Peolsson Anneli , Petzke Frank , Davey Paul , Falla Deborah
Published: February 2017

Delayed onset of muscle activation can be a descriptor of impaired motor control. Activation onset can be estimated from electromyography (EMG)-registered muscle excitation and from ultrasound-registered muscle motion, which enables non-invasive measurements in deep muscles. However, in voluntary activation, EMG- and ultrasound-detected activation onsets may not correspond. To evaluate this, ten healthy men performed isometric elbow flexion at 20% to 70% of their maximal force. Utilising a multi-channel electrode transparent to ultrasound, EMG and M(otion)-mode ultrasound were recorded simultaneously over the biceps brachii muscle. The time intervals between automated and visually estimated activation onsets were correlated with the regional variation of EMG and muscle motion onset, contraction level and speed. Automated and visual onsets indicated variable time intervals between EMG- and motion onset, median (interquartile range) 96 (121) ms and 48 (72) ms, respectively. In 17% (computed analysis) or 23% (visual analysis) of trials, motion onset was detected before local EMG onset. Multi-channel EMG and M-mode ultrasound revealed regional differences in activation onset, which decreased with higher contraction speed (Spearman ρ ≥ 0.45, P < 0.001). In voluntary activation the heterogeneous motor unit recruitment together with immediate motion transmission may explain the high variation of the time intervals between local EMG- and ultrasound-detected activation onset.
The interaction of perceptual biases in bistable perception
Authors: Zhang Xue , Xu Qian , Jiang Yi , Wang Ying
Published: February 2017

When viewing ambiguous stimuli, people tend to perceive some interpretations more frequently than others. Such perceptual biases impose various types of constraints on visual perception, and accordingly, have been assumed to serve distinct adaptive functions. Here we demonstrated the interaction of two functionally distinct biases in bistable biological motion perception, one regulating perception based on the statistics of the environment – the viewing-from-above (VFA) bias, and the other with the potential to reduce costly errors resulting from perceptual inference – the facing-the-viewer (FTV) bias. When compatible, the two biases reinforced each other to enhance the bias strength and induced less perceptual reversals relative to when they were in conflict. Whereas in the conflicting condition, the biases competed with each other, with the dominant percept varying with visual cues that modulate the two biases separately in opposite directions. Crucially, the way the two biases interact does not depend on the dominant bias at the individual level, and cannot be accounted for by a single bias alone. These findings provide compelling evidence that humans robustly integrate biases with different adaptive functions in visual perception. It may be evolutionarily advantageous to dynamically reweight diverse biases in the sensory context to resolve perceptual ambiguity.
Enhancing the biocatalytic manufacture of the key intermediate of atorvastatin by focused directed evolution of halohydrin dehalogenase
Authors: Luo Yu , Chen Yangzi , Ma Hongmin , Tian ZhenHua , Zhang Yeqi , Zhang Jian
Published: February 2017

Halohydrin dehalogenases (HHDHs) are biocatalytically interesting enzymes due to their ability to form C-C, C-N, C-O, and C-S bonds. One of most important application of HHDH was the protein engineering of HheC (halohydrin dehalogenase from Agrobacterium radiobacter AD1) for the industrial manufacturing of ethyl (R)-4-cyano-3-hydroxybutanoate (HN), a key chiral synthon of a cholesterol-lowering drug of atorvastatin. During our development of an alternative, more efficient and economic route for chemo-enzymatic preparation of the intermediate of atorvastatin, we found that the HheC2360 previously reported for HN manufacture, had insufficient activity for the cyanolysis production of tert-butyl (3 R,5 S)-6-cyano-3,5-dihydroxyhexanoate (A7). Herein, we present the focused directed evolution of HheC2360 with higher activity and enhanced biocatalytic performance using active site mutagenesis. Through docking of the product, A7, into the crystal structure of HheC2360, 6 residues was selected for combined active sites testing (CASTing). After library screening, the variant V84G/W86F was identified to have a 15- fold increase in activity. Time course analysis of the cyanolysis reaction catalyzed by this variant, showed 2- fold increase in space time productivity compared with HheC2360. These results demonstrate the applicability of the variant V84G/W86F as a biocatalyst for the efficient and practical production of atorvastatin intermediate.
Interplay between the static ordering and dynamical heterogeneities determining the dynamics of rotation and ordinary liquid phases in 1,6-anhydro-β-D-glucose
Authors: Madejczyk O. , Kaminski K. , Kaminska E. , Jurkiewicz K. , Tarnacka M. , Burian A. , Paluch M.
Published: February 2017

In this letter, we reported thorough the structural and molecular dynamics studies on 1,6-anhydro-β-D-glucose, the second compound reported so far that is capable to form rotator and supercooled liquid phases. In contrast to the data presented for ethanol, temperature dependences of structural dynamics in both phases are very comparable. On the other hand, X ray measurements revealed unusually long range ordering/correlations between molecules in the ODIC (d ≈ 95 Å) and supercooled phases (d ≈ 30–40 Å) of this carbohydrate. Our consideration clearly demonstrated that the interplay between length scales of static range ordering and dynamical heterogeneities as well as internal molecular arrangement seem to be the key to understanding the molecular dynamics of different materials characterized by varying degree of disorder in the vicinity of the glass transition temperature.
Characterization of Adipogenic Chemicals in Three Different Cell Culture Systems: Implications for Reproducibility Based on Cell Source and Handling
Authors: Kassotis Christopher D. , Masse Lauren , Kim Stephanie , Schlezinger Jennifer J. , Webster Thomas F. , Stapleton Heather M.
Published: February 2017

The potential for chemical exposures to exacerbate the development and/or prevalence of metabolic disorders, such as obesity, is currently of great societal concern. Various in vitro assays are available to assess adipocyte differentiation, though little work has been done to standardize protocols and compare models effectively. This study compares several adipogenic cell culture systems under a variety of conditions to assess variability in responses. Two sources of 3T3-L1 preadipocytes as well as OP9 preadipocytes were assessed for cell proliferation and triglyceride accumulation following different induction periods and using various tissue culture plates. Both cell line and cell source had a significant impact on potencies and efficacies of adipogenic chemicals. Gene expression analyses suggested that differential expression of nuclear receptors involved in adipogenesis underlie the differences between OP9 and 3T3-L1 cells; however, there were also differences based on 3T3-L1 cell source. Induction period modulated potency and efficacy of response depending on cell line and test chemical, and large variations were observed in triglyceride accumulation and cell proliferation between brands of tissue culture plates. Our results suggest that the selection of a cell system and differentiation protocol significantly impacts the detection of adipogenic chemicals, and therefore, influences reproducibility of these studies.
A versatile assay to determine bacterial and host factors contributing to opsonophagocytotic killing in hirudin-anticoagulated whole blood
Authors: van der Maten Erika , de Jonge Marien I. , de Groot Ronald , van der Flier Michiel , Langereis Jeroen D.
Published: February 2017

Most bacteria entering the bloodstream will be eliminated through complement activation on the bacterial surface and opsonophagocytosis. However, when these protective innate immune systems do not work optimally, or when bacteria are equipped with immune evasion mechanisms that prevent killing, this can lead to serious infections such as bacteremia and meningitis, which is associated with high morbidity and mortality. In order to study the complement evasion mechanisms of bacteria and the capacity of human blood to opsonize and kill bacteria, we developed a versatile whole blood killing assay wherein both phagocyte function and complement activity can easily be monitored and modulated. In this assay we use a selective thrombin inhibitor hirudin to fully preserve complement activity of whole blood. This assay allows controlled analysis of the requirements for active complement by replacing or heat-inactivating plasma, phagocyte function and bacterial immune evasion mechanisms that contribute to survival in human blood.
Human embryonic and induced pluripotent stem cells maintain phenotype but alter their metabolism after exposure to ROCK inhibitor
Authors: Vernardis Spyros I. , Terzoudis Konstantinos , Panoskaltsis Nicki , Mantalaris Athanasios
Published: February 2017

Human pluripotent stem cells (hPSCs) are adhesion-dependent cells that require cultivation in colonies to maintain growth and pluripotency. Robust differentiation protocols necessitate single cell cultures that are achieved by use of ROCK (Rho kinase) inhibitors. ROCK inhibition enables maintenance of stem cell phenotype; its effects on metabolism are unknown. hPSCs were exposed to 10 μM ROCK inhibitor for varying exposure times. Pluripotency (TRA-1-81, SSEA3, OCT4, NANOG, SOX2) remained unaffected, until after prolonged exposure (96 hrs). Gas chromatography–mass spectrometry metabolomics analysis identified differences between ROCK-treated and untreated cells as early as 12 hrs. Exposure for 48 hours resulted in reduction in glycolysis, glutaminolysis, the citric acid (TCA) cycle as well as the amino acids pools, suggesting the adaptation of the cells to the new culture conditions, which was also reflected by the expression of the metabolic regulators, mTORC1 and tp53 and correlated with cellular proliferation status. While gene expression and protein levels did not reveal any changes in the physiology of the cells, metabolomics revealed the fluctuating state of the metabolism. The above highlight the usefulness of metabolomics in providing accurate and sensitive information on cellular physiological status, which could lead to the development of robust and optimal stem cell bioprocesses.
Risk profile and HIV testing outcomes of women undergoing community-based testing in San Diego 2008–2014
Authors: Graves Susannah K. , Little Susan J. , Hoenigl Martin
Published: February 2017

Women comprised 19% of new HIV diagnoses in the United States in 2014, with significant racial and ethnic disparities in infection rates. This cross-sectional analysis of women enrolled in a cohort study compares demographics, risk behaviour, and sexually transmitted infections (STI) in those undergoing HIV testing in San Diego County. Data from the most recent screening visit of women undergoing voluntary HIV screening April 2008 –July 2014 was used. HIV diagnosis, risk behaviour and self-reported STIs were compared among women aged ≤24, 25–49, and ≥50, as well as between HIV-infected and uninfected women and between Hispanic and non-Hispanic women. Among the 2535 women included, Hispanic women were less likely than other women to report unprotected vaginal intercourse (p = 0.026) or stimulant drug use (p = 0.026), and more likely to report one or fewer partners (p < 0.0001), but also more likely to report sex with an HIV-infected individual (p = 0.027). New HIV infection was significantly more prevalent among Hispanic women (1.6% vs. 0.2%; p < 0.001). Hispanic women were more likely than other women to be diagnosed with HIV despite significantly lower rates of risk behaviour. Culturally specific risk reduction interventions for Hispanic women should focus on awareness of partner risk and appropriate testing.
Angle-independent pH-sensitive composites with natural gyroid structure
Authors: Xue Ruiyang , Zhang Wang , Sun Peng , Zada Imran , Guo Cuiping , Liu Qinglei , Gu Jiajun , Su Huilan , Zhang Di
Published: February 2017

pH sensor is an important and practical device with a wide application in environmental protection field and biomedical industries. An efficient way to enhance the practicability of intelligent polymer composed pH sensor is to subtilize the three-dimensional microstructure of the materials, adding measurable features to visualize the output signal. In this work, C. rubi wing scales were combined with pH-responsive smart polymer polymethylacrylic acid (PMAA) through polymerization to achieve a colour-tunable pH sensor with nature gyroid structure. Morphology and reflection characteristics of the novel composites, named G-PMAA, are carefully investigated and compared with the original biotemplate, C. rubi wing scales. The most remarkable property of G-PMAA is a single-value corresponding relationship between pH value and the reflection peak wavelength (λmax), with a colour distinction degree of 18 nm/pH, ensuring the accuracy and authenticity of the output. The pH sensor reported here is totally reversible, which is able to show the same results after several detection circles. Besides, G-PMAA is proved to be not influenced by the detection angle, which makes it a promising pH sensor with superb sensitivity, stability, and angle-independence.
Magnetic hard gap due to bound magnetic polarons in the localized regime
Authors: Rimal Gaurab , Tang Jinke
Published: February 2017

We investigate the low temperature electron transport properties of manganese doped lead sulfide films. The system shows variable range hopping at low temperatures that crosses over into an activation regime at even lower temperatures. This crossover is destroyed by an applied magnetic field which suggests a magnetic origin of the hard gap, associated with bound magnetic polarons. Even though the gap forms around the superconducting transition temperature of lead, we do not find evidence of this being due to insulator-superconductor transition. Comparison with undoped PbS films, which do not show the activated transport behavior, suggests that bound magnetic polarons create the hard gap in the system that can be closed by magnetic fields.
Primary macrophages and J774 cells respond differently to infection with Mycobacterium tuberculosis
Authors: Andreu Nuria , Phelan Jody , de Sessions Paola F. , Cliff Jacqueline M. , Clark Taane G. , Hibberd Martin L.
Published: February 2017

Macrophages play an essential role in the early immune response to Mycobacterium tuberculosis and are the cell type preferentially infected in vivo. Primary macrophages and macrophage-like cell lines are commonly used as infection models, although the physiological relevance of cell lines, particularly for host-pathogen interaction studies, is debatable. Here we use high-throughput RNA-sequencing to analyse transcriptome dynamics of two macrophage models in response to M. tuberculosis infection. Specifically, we study the early response of bone marrow-derived mouse macrophages and cell line J774 to infection with live and γ-irradiated (killed) M. tuberculosis. We show that infection with live bacilli specifically alters the expression of host genes such as Rsad2, Ifit1/2/3 and Rig-I, whose potential roles in resistance to M. tuberculosis infection have not yet been investigated. In addition, the response of primary macrophages is faster and more intense than that of J774 cells in terms of number of differentially expressed genes and magnitude of induction/repression. Our results point to potentially novel processes leading to immune containment early during M. tuberculosis infection, and support the idea that important differences exist between primary macrophages and cell lines, which should be taken into account when choosing a macrophage model to study host-pathogen interactions.
CXCL12/CXCR4 axis induced miR-125b promotes invasion and confers 5-fluorouracil resistance through enhancing autophagy in colorectal cancer
Authors: Yu Xinfeng , Shi Wenna , Zhang Yuhang , Wang Xiaohui , Sun Shiyue , Song Zhiyu , Liu Man , Zeng Qiao , Cui Shuxiang , Qu Xianjun
Published: February 2017

The activation of CXCL12/CXCR4 axis is associated with potential progression of cancer, such as invasion, metastasis and chemoresistance. However, the underlying mechanisms of CXCL12/CXCR4 axis and cancer progression have been poorly explored. We hypothesized that miRNAs might be critical downstream mediators of CXCL12/CXCR4 axis involved in cancer invasion and chemoresistance in CRC. In human CRC cells, we found that the activation of CXCL12/CXCR4 axis promoted epithelial-mesenchymal transition (EMT) and concurrent upregulation of miR-125b. Overexpression of miR-125b robustly triggered EMT and cancer invasion, which in turn enhanced the expression of CXCR4. Importantly, the reciprocal positive feedback loop between CXCR4 and miR-125b further activated the Wnt/β-catenin signaling by targeting Adenomatous polyposis coli (APC) gene. There was a negative correlation of the expression of miR-125b with APC mRNA in paired human colorectal tissue specimens. Further experiments indicated a role of miR-125b in conferring 5-fluorouracil (5-FU) resistance in CRC probably through increasing autophagy both in vitro and in vivo. MiR-125b functions as an important downstream mediator upon the activation of CXCL12/CXCR4 axis that involved in EMT, invasion and 5-FU resistance of CRC. These findings shed a new insight into the role of miR-125b and provide a potential therapeutic target in CRC.
PARP inhibitor increases chemosensitivity by upregulating miR-664b-5p in BRCA1-mutated triple-negative breast cancer
Authors: Song Wei , Tang Lin , Xu Yumei , Xu Jing , Zhang Wenwen , Xie Hui , Wang Shui , Guan Xiaoxiang
Published: February 2017

Emerging evidence has shown that adding poly(ADP-ribose) polymerase (PARP) inhibitors to chemotherapy regimens is superior to the control regimens alone in BRCA1-mutated triple-negative breast cancer (TNBC) patients, but their underlying mechanisms have not been fully elucidated. In this study, using miRNA microarray analysis of two BRCA1-mutated TNBC cell lines, we found that miR-664b-5p expression was increased after adding a PARP inhibitor, olaparib, to a carboplatin (CBP) plus gemcitabine (GEM) therapy regimen. Functional assays showed miR-664b-5p overexpression inhibited proliferation, migration and invasion in BRCA1-mutated TNBC cells. CCNE2 was identified as a novel functional target of miR-664b-5p, and CCNE2 knockdown revealed effects similar to those observed with miR-664b-5p overexpression. Both CCNE2 knockdown and miR-664b-5p overexpression significantly increased the chemosensitivity of BRCA1-mutated TNBC cells. In addition, in vivo studies indicated that miR-664b-5p inhibited tumour growth compared with the control in tumour xenograft models, and we also found that CCNE2 expression was inversely correlated with miR-664b-5p expression in 90 TNBC patient samples. In conclusion, miR-664b-5p functions as a tumour suppressor and has an important role in the regulation of PARP inhibitors to increase chemosensitivity by targeting CCNE2. This may be one of the possible mechanisms by which PARP inhibitors increase chemosensitivity in BRCA1-mutated TNBC.
Modified forelimb grip strength test detects aging-associated physiological decline in skeletal muscle function in male mice
Authors: Takeshita Hikari , Yamamoto Koichi , Nozato Satoko , Inagaki Tadakatsu , Tsuchimochi Hirotsugu , Shirai Mikiyasu , Yamamoto Ryohei , Imaizumi Yuki , Hongyo Kazuhiro , Yokoyama Serina , Takeda Masao , Oguro Ryosuke , Takami Yoichi , Itoh Norihisa , Takeya Yasushi , Sugimoto Ken , Fukada So-ichiro , Rakugi Hiromi
Published: February 2017

The conventional forelimb grip strength test is a widely used method to assess skeletal muscle function in rodents; in this study, we modified this method to improve its variability and consistency. The modified test had lower variability among trials and days than the conventional test in young C57BL6 mice, especially by improving the variabilities in male. The modified test was more sensitive than the conventional test to detect a difference in motor function between female and male mice, or between young and old male mice. When the modified test was performed on male mice during the aging process, reduction of grip strength manifested between 18 and 24 months of age at the group level and at the individual level. The modified test was similar to the conventional test in detecting skeletal muscle dysfunction in young male dystrophic mice. Thus, the modified forelimb grip strength test, with its improved validity and reliability may be an ideal substitute for the conventional method.
Alleviation of drought stress by mycorrhizas is related to increased root H2O2 efflux in trifoliate orange
Authors: Huang Yong-Ming , Zou Ying-Ning , Wu Qiang-Sheng
Published: February 2017

The Non-invasive Micro-test Technique (NMT) is used to measure dynamic changes of specific ions/molecules non-invasively, but information about hydrogen peroxide (H2O2) fluxes in different classes of roots by mycorrhiza is scarce in terms of NMT. Effects of Funneliformis mosseae on plant growth, H2O2, superoxide radical (O2·−), malondialdehyde (MDA) concentrations, and H2O2 fluxes in the taproot (TR) and lateral roots (LRs) of trifoliate orange seedlings under well-watered (WW) and drought stress (DS) conditions were studied. DS strongly inhibited mycorrhizal colonization in the TR and LRs, whereas mycorrhizal inoculation significantly promoted plant growth and biomass production. H2O2, O2·−, and MDA concentrations in leaves and roots were dramatically lower in mycorrhizal seedlings than in non-mycorrhizal seedlings under DS. Compared with non-mycorrhizal seedlings, mycorrhizal seedlings had relatively higher net root H2O2 effluxes in the TR and LRs especially under WW, as well as significantly higher total root H2O2 effluxes in the TR and LRs under WW and DS. Total root H2O2 effluxes were significantly positively correlated with root colonization but negatively with root H2O2 and MDA concentrations. It suggested that mycorrhizas induces more H2O2 effluxes of the TR and LRs, thus, alleviating oxidative damage of DS in the host plant.
A paper-based platform for detection of viral RNA
Authors: Zhang Daohong , Broyles David , Hunt Eric A. , Dikici Emre , Daunert Sylvia , Deo Sapna K.
Published: February 2017

Viral detection presents a host of challenges for even the most sensitive analytical techniques, and the complexity of common detection platforms typically preclude portability.
Retinal oxidative stress at the onset of diabetes determined by synchrotron FTIR widefield imaging: towards diabetes pathogenesis
Authors: Aboualizadeh Ebrahim , Ranji Mahsa , Sorenson Christine M. , Sepehr Reyhaneh , Sheibani Nader , Hirschmugl Carol J.
Published: February 2017

A mechanistic understanding of oxidative damage in the retina and the significance of photoreceptors at the onset of diabetic retinopathy are reported.
High-throughput analysis of endogenous fruit glycosyl hydrolases using a novel chromogenic hydrogel substrate assay
Authors: Schückel Julia , Kračun Stjepan Krešimir , Lausen Thomas Frederik , Tycho Willats William George , Jørgensen Bodil
Published: February 2017

A broad range of enzyme activities can be found in a wide range of different fruits and fruiting bodies and we demonstrate how many samples and diverse activities can be handled in a high-throughput and efficient manner.
Improving gelation efficiency and cytocompatibility of visible light polymerized thiol-norbornene hydrogels via addition of soluble tyrosine
Authors: Shih Han , Liu Hung-Yi , Lin Chien-Chi
Published: February 2017

A biomimetic PEG-peptide hydrogel was developed through tyrosine-assisted visible-light thiol-norbornene crosslinking. Soluble tyrosine improves crosslinking and enhances the cytocompatibility of hydrogels.
Trapping shape-controlled nanoparticle nucleation and growth stages via continuous-flow chemistry
Authors: LaGrow Alec P. , Besong Tabot M. D. , AlYami Noktan M. , Katsiev Khabiboulakh , Anjum Dalaver H. , Abdelkader Ahmed , Costa Pedro M. F. J. , Burlakov Victor M. , Goriely Alain , Bakr Osman M.
Published: February 2017

Trapping nucleation and growth stages of shape controlled nanoparticles with second time resolution and high throughputs via continuous flow chemistry.
Electrochemical probing of hydrogelation induced by the self-assembly of a donor–acceptor complex comprising pyranine and viologen
Authors: Datta Sougata , Dey Nilanjan , Bhattacharya Santanu
Published: February 2017

We report the electrochemical analysis of a donor–acceptor type two-component hydrogelation by an electroactive co-assembly of pyranine and n-dodecyl methyl viologen.
A facile approach for the synthesis of hydroxyl-rich microporous organic networks for efficient CO2capture and H2storage
Authors: Mondal Sujan , Kundu Sudipta K. , Bhaumik Asim
Published: February 2017

A new series of porous organic networks (PONs) with N-donor sites and free hydroxyl groups in the backbone have been synthesized under high vacuum sealed tube conditions. These PONs possess high BET surface area and showed excellent H2and CO2storage capacities.
Brønsted acid-catalyzed stereoselective [4+3] cycloadditions of ortho-hydroxybenzyl alcohols with N,N′-cyclic azomethine imines
Authors: Mei Guang-Jian , Zhu Zi-Qi , Zhao Jia-Jia , Bian Chen-Yu , Chen Jie , Chen Ruo-Wei , Shi Feng
Published: February 2017

The first [4+3] cycloaddition of ortho-hydroxybenzyl alcohols has been established to construct biologically important seven-membered heterocyclic scaffolds in good yields and excellent diastereoselectivities (up to 92% yield, most >95 : 5 dr).
Dendritic poly-chelator frameworks for multimeric bioconjugation
Authors: Reich Dominik , Wurzer Alexander , Wirtz Martina , Stiegler Veronika , Spatz Philipp , Pollmann Julia , Wester Hans-Jürgen , Notni Johannes
Published: February 2017

Dendrimers built of chelators show unparalleled Ga(III) complexation efficiency and allow for synthesis of highly symmetrical bifunctional poly-bioconjugates via Click-Chemistry.
A combined high-temperature experimental and theoretical kinetic study of the reaction of dimethyl carbonate with OH radicals
Authors: Khaled Fethi , Giri Binod Raj , Szőri Milán , Mai Tam V.-T. , Huynh Lam K. , Farooq Aamir
Published: February 2017

The reaction kinetics of dimethyl carbonate (DMC) and OH radicals were investigated behind reflected shock waves over the temperature range of 872–1295 K and at pressures near 1.5 atm.
New insights into the electroreduction of ethylene sulfite as an electrolyte additive for facilitating solid electrolyte interphase formation in lithium ion batteries
Authors: Sun Youmin , Wang Yixuan
Published: February 2017

The electroreduction of ES, an additive of the electrolyte of lithium-ion batteries was theoretically reinvestigated. The newly located concerted pathway has lower energy barrier than the stepwise pathway in literature.
Ligand effects in rhodium-catalyzed hydroformylation with bisphosphines: steric or electronic?
Authors: Jiao Yunzhe , Torne Marta Serrano , Gracia Jose , Niemantsverdriet J. W. (Hans) , van Leeuwen Piet W. N. M.
Published: February 2017

Do wide bite angles lead to high linear regioselectivity in hydroformylation, or is an electronic effect operative?
A heteroelectrode structure for solar water splitting: integrated cobalt ditelluride across a TiO2-passivated silicon microwire array
Authors: Bazri Behrouz , Lin Yu-Chen , Lu Tzu-Hsiang , Chen Chih-Jung , Kowsari Elaheh , Hu Shu-Fen , Liu Ru-Shi
Published: February 2017

CoTe2@TiO2-Si-MWs provide active sites for proton reduction and combine surface hydrogen atoms into molecular hydrogen.
Structural transformations of layered structures constructed from Cu(ii)–chloranilate monomer compounds
Authors: Yagishita Sadahiro , Himegi Akiko , Kanazashi Ken , Ohishi Tomomi , Ishikawa Ryuta , Hamaguchi Tomohiko , Kawata Satoshi
Published: February 2017

New organic–inorganic hybrid layered compounds, which have flexibilities both in the inter- and intra-layers, have been prepared and characterized.
Highly efficient hydrogen evolution from seawater by a low-cost and stable CoMoP@C electrocatalyst superior to Pt/C
Authors: Ma Yuan-Yuan , Wu Cai-Xia , Feng Xiao-Jia , Tan Hua-Qiao , Yan Li-Kai , Liu Yang , Kang Zhen-Hui , Wang En-Bo , Li Yang-Guang
Published: February 2017

A low-cost CoMoP@C electrocatalyst exhibits high efficiency and stable HER performance superior to commercial 20% Pt/C, and can directly work in seawater for the HER with a Faradaic efficiency of 92.5%.
Synergetic effects of K+and Mg2+ion intercalation on the electrochemical and actuation properties of the two-dimensional Ti3C2MXene
Authors: Gao Qiang , Come Jeremy , Naguib Michael , Jesse Stephen , Gogotsi Yury , Balke Nina
Published: February 2017

Two-dimensional materials, such as MXenes, are attractive candidates for energy storage and electrochemical actuators due to their high volume changes upon ion intercalation. Of special interest for boosting energy storage is the intercalation of multivalent ions such as Mg2+, which suffers from sluggish intercalation and transport kinetics due to its ion size. By combining traditional electrochemical characterization techniques with electrochemical dilatometry and contact resonance atomic force microscopy, the synergetic effects of the pre-intercalation of K+ions are demonstrated to improve the charge storage of multivalent ions, as well as tune the mechanical and actuation properties of the Ti3C2MXene. Our results have important implications for quantitatively understanding the charge storage processes in intercalation compounds and provide a new path for studying the mechanical evolution of energy storage materials.
Physicochemical properties of kafirin protein and its applications as building blocks of functional delivery systems
Authors: Xiao Jie , Chen Yunjiao , Huang Qingrong
Published: February 2017

The unique physicochemical properties of kafirin highlight its potential as an attractive resource for gluten-free products and building blocks for functional delivery systems.