bluuebunny/crossref_metadata_2025_split huggingface dataset:
Requirement of phospholipase C and protein kinase C in cholecystokinin‐mediated facilitation of NMDA channel function and anxiety‐like behavior
Authors: Xiao Zhaoyang , Jaiswal Manoj K. , Deng Pan‐Yue , Matsui Toshimitsu , Shin Hee‐Sup , Porter James E. , Lei Saobo 
Published: November 2011

AbstractAlthough cholecystokinin (CCK) has long been known to exert anxiogenic effects in both animal anxiety models and humans, the underlying cellular and molecular mechanisms are ill‐defined. CCK interacts with CCK‐1 and CCK‐2 receptors resulting in up‐regulation of phospholipase C (PLC) and protein kinase C (PKC). However, the roles of PLC and PKC in CCK‐mediated anxiogenic effects have not been determined. We have shown previously that CCK facilitates glutamate release in the hippocampus especially at the synapses formed by the perforant path and dentate gyrus granule cells via activations of PLC and PKC. Here we further demonstrated that CCK enhanced NMDA receptor function in dentate gyrus granule cells via activation of PLC and PKC pathway. At the single‐channel level, CCK increased NMDA single‐channel open probability and mean open time, reduced the mean close time, and had no effects on the conductance of NMDA channels. Because elevation of glutamatergic functions results in anxiety, we explored the roles of PLC and PKC in CCK‐induced anxiogenic actions using the Vogel Conflict Test (VCT). Our results from both pharmacological approach and knockout mice demonstrated that microinjection of CCK into the dentate gyrus concentration‐dependently increased anxiety‐like behavior via activation of PLC and PKC. Our results provide a novel unidentified signaling mechanism whereby CCK increases anxiety. © 2011 Wiley Periodicals, Inc.
A possible overestimation of the effect of acetylation on lysine residues in KQ mutant analysis
Authors: Fujimoto Hirofumi , Higuchi Mariko , Koike Manabu , Ode Hirotaka , Pinak Miroslav , Bunta Juraj Kotulic , Nemoto Toshiyuki , Sakudoh Takashi , Honda Naoko , Maekawa Hideaki , Saito Kimiaki , Tsuchida Kozo 
Published: November 2011

AbstractAcetylation of lysine residues, one of the most common protein post‐transcriptional modifications, is thought to regulate protein affinity with other proteins or nucleotides. Experimentally, the effects of acetylation have been studied using recombinant mutants in which lysine residues (K) are substituted with glutamine (Q) as a mimic of acetyl lysine (KQ mutant), or with arginine (R) as a mimic of nonacetylated lysine (KR mutant). These substitutions, however, have not been properly validated. The effects lysine acetylation on Ku, a multifunctional protein that has been primarily implicated in DNA repair and cell survival, are characterized herein using a series of computer simulations. The binding free energy was reduced in the KQ mutant, while the KR mutant had no effect, which is consistent with previous experimental results. Unexpectedly, the binding energy between Ku and DNA was maintained at almost the same level as in the wild type protein despite full acetylation of the lysine residues. These results suggest that the effects of acetylation may be overestimated when the KQ mutant is used as a mimic of the acetylated protein. © 2011 Wiley Periodicals, Inc. J Comput Chem 2012
Protective Effect of Calamintha officinalis Moench Leaves against Alcohol‐induced Gastric Mucosa Injury in Rats. Macroscopic, Histologic and Phytochemical Analysis
Authors: Monforte M. T. , Lanuzza F. , Pergolizzi S. , Mondello F. , Tzakou O. , Galati E. M. 
Published: November 2011

Calamintha officinalis Moench (Lamiaceae) is an aromatic plant used since ancient times for its preservative and medicinal properties. The plant, known as ‘Mentuccia’ in Central Italy, is used in cooking as an aromatizant and to impart aroma and flavour to food. The methanol extract of the leaves was subjected to phytochemical and biological investigations. The extract contains polyphenols, catechic tannins and terpenes and shows radical scavenger activity. By means of HPLC analysis, eriocitrin, eriodyctiol, acacetin, linarin, benzoic acid and some phenolic acids, such as caffeic, chlorogenic, p‐coumaric, were determined. The gastroprotective activity of the extract was investigated using ethanol‐induced ulcer in rats, with sucralfate as a reference drug. Samples of gastric mucosa, stained by PAS and haematoxylin/eosin, were observed by light microscopy. The efficacy of the extract was comparable to that of the reference drug.Probably the gastroprotective effect depends on a synergistic action of all the compounds occurring in C. officinalis leaves, even if the antioxidant potential of the leaves plays an important role by removing damaging agents from the gastric mucosa. Copyright © 2011 John Wiley & Sons, Ltd.
Barx2 Is Expressed in Satellite Cells and Is Required for Normal Muscle Growth and Regeneration
Authors: Meech Robyn , Gonzalez Katie N. , Barro Marietta , Gromova Anastasia , Zhuang Lizhe , Hulin Julie-Ann , Makarenkova Helen P. 
Published: November 2011

Abstract
Muscle growth and regeneration are regulated through a series of spatiotemporally dependent signaling and transcriptional cascades. Although the transcriptional program controlling myogenesis has been extensively investigated, the full repertoire of transcriptional regulators involved in this process is far from defined. Various homeodomain transcription factors have been shown to play important roles in both muscle development and muscle satellite cell-dependent repair. Here, we show that the homeodomain factor Barx2 is a new marker for embryonic and adult myoblasts and is required for normal postnatal muscle growth and repair. Barx2 is coexpressed with Pax7, which is the canonical marker of satellite cells, and is upregulated in satellite cells after muscle injury. Mice lacking the Barx2 gene show reduced postnatal muscle growth, muscle atrophy, and defective muscle repair. Moreover, loss of Barx2 delays the expression of genes that control proliferation and differentiation in regenerating muscle. Consistent with the in vivo observations, satellite cell-derived myoblasts cultured from Barx2−/− mice show decreased proliferation and ability to differentiate relative to those from wild-type or Barx2+/− mice. Barx2−/− myoblasts show reduced expression of the differentiation-associated factor myogenin as well as cell adhesion and matrix molecules. Finally, we find that mice lacking both Barx2 and dystrophin gene expression have severe early onset myopathy. Together, these data indicate that Barx2 is an important regulator of muscle growth and repair that acts via the control of satellite cell proliferation and differentiation.
Disclosure of potential conflicts of interest is found at the end of this article.
Guided Migration of Neural Stem Cells Derived from Human Embryonic Stem Cells by an Electric Field
Authors: Feng Jun-Feng , Liu Jing , Zhang Xiu-Zhen , Zhang Lei , Jiang Ji-Yao , Nolta Jan , Zhao Min 
Published: November 2011

Abstract
Small direct current (DC) electric fields (EFs) guide neurite growth and migration of rodent neural stem cells (NSCs). However, this could be species dependent. Therefore, it is critical to investigate how human NSCs (hNSCs) respond to EF before any possible clinical attempt. Aiming to characterize the EF-stimulated and guided migration of hNSCs, we derived hNSCs from a well-established human embryonic stem cell line H9. Small applied DC EFs, as low as 16 mV/mm, induced significant directional migration toward the cathode. Reversal of the field polarity reversed migration of hNSCs. The galvanotactic/electrotactic response was both time and voltage dependent. The migration directedness and distance to the cathode increased with the increase of field strength. (Rho-kinase) inhibitor Y27632 is used to enhance viability of stem cells and has previously been reported to inhibit EF-guided directional migration in induced pluripotent stem cells and neurons. However, its presence did not significantly affect the directionality of hNSC migration in an EF. Cytokine receptor [C-X-C chemokine receptor type 4 (CXCR4)] is important for chemotaxis of NSCs in the brain. The blockage of CXCR4 did not affect the electrotaxis of hNSCs. We conclude that hNSCs respond to a small EF by directional migration. Applied EFs could potentially be further exploited to guide hNSCs to injured sites in the central nervous system to improve the outcome of various diseases.
Disclosure of potential conflicts of interest is found at the end of this article.
Nonaddictive instrumental drug use: Theoretical strengths and weaknesses
Authors: Goudie Andrew J. , Gullo Matthew J. , Rose Abigail K. , Christiansen Paul , Cole Jonathan C. , Field Matt , Sumnall Harry 
Published: November 2011

AbstractThe potential to instrumentalize drug use based upon the detection of very many different drug states undoubtedly exists, and such states may play a role in psychiatric and many other drug uses. Nevertheless, nonaddictive drug use is potentially more parsimoniously explained in terms of sensation seeking/impulsivity and drug expectations. Cultural factors also play a major role in nonaddictive drug use.
The planet companion around β Pictoris
Authors: Lagrange Anne-Marie , Bonnefoy Mickaël , Chauvin Gael , Apai Daniel , Ehrenreich David , Boccaletti Anthony , Gratadour Damien , Rouan Daniel , Mouillet David , Lacour Sylvestre , Kasper Markus 
Published: November 2011

AbstractThe β Pic disk of dust and gas has been regarded as the prototype of young planetary systems since the 1980s and has revealed over the years an impressive amount of indirect signs pointing toward the presence of at least one giant planet. We present here the recently detected first giant planet around this star. We show how this planet could explain some very peculiar features of the star environment (disk, spectroscopic variability), and how it constrains the scenarios of planetary system formation (timescales, mechanisms).
High-resolution simulations of planetesimal formation in turbulent protoplanetary discs
Authors: Johansen Anders , Klahr Hubert , Henning Thomas 
Published: November 2011

AbstractWe present high resolution computer simulations of dust dynamics and planetesimal formation in turbulence triggered by the magnetorotational instability. Particles representing approximately meter-sized boulders clump in large scale overpressure regions in the simulation box. These overdensities readily contract due to the combined gravity of the particles to form gravitationally bound clusters with masses ranging from a few to several ten times the mass of the dwarf planet Ceres. Gravitationally bound clumps are observed to collide and merge at both moderate and high resolution. The collisional products form the top end of a distribution of planetesimal masses ranging from less than one Ceres mass to 35 Ceres masses. It remains uncertain whether collisions are driven by dynamical friction or underresolution of clumps.
The properties of super-Earth atmospheres
Authors: Kempton Eliza M. R. 
Published: November 2011

AbstractExtrasolar super-Earths likely have a far greater diversity in their atmospheric properties than giant planets. Super-Earths (planets with masses between 1 and 10 M⊕) lie in an intermediate mass regime between gas/ice giants like Neptune and rocky terrestrial planets like Earth and Venus. While some super-Earths (especially the more massive ones) may retain large amounts of hydrogen either from accretion processes or subsequent surface outgassing, other super-Earths should have atmospheres composed of predominantly heavier molecules, similar to the atmospheres of the rocky planets and moons of our Solar System. Others still may be entirely stripped of their atmospheres and remain as bare rocky cores. Of the two currently known transiting super-Earths one (GJ 1214b) likely falls into the former category with a thick atmosphere, while the other (CoRoT-7b) falls into the latter category with a very thin or nonexistent atmosphere. I review some of the theoretical work on super-Earth atmospheres, and I present methods for determining the bulk composition of a super-Earth atmosphere.
Hamiltonian model of capture into mean motion resonance
Authors: Mustill Alexander J. , Wyatt Mark C. 
Published: November 2011

AbstractMean motion resonances are a common feature of both our own Solar System and of extrasolar planetary systems. Bodies can be trapped in resonance when their orbital semi-major axes change, for instance when they migrate through a protoplanetary disc. We use a Hamiltonian model to thoroughly investigate the capture behaviour for first and second order resonances. Using this method, all resonances of the same order can be described by one equation, with applications to specific resonances by appropriate scaling. We focus on the limit where one body is a massless test particle and the other a massive planet. We quantify how the the probability of capture into a resonance depends on the relative migration rate of the planet and particle, and the particle's eccentricity. Resonant capture fails for high migration rates, and has decreasing probability for higher eccentricities, although for certain migration rates, capture probability peaks at a finite eccentricity. We also calculate libration amplitudes and the offset of the libration centres for captured particles, and the change in eccentricity if capture does not occur. Libration amplitudes are higher for larger initial eccentricity. The model allows for a complete description of a particle's behaviour as it successively encounters several resonances. The model is applicable to many scenarios, including (i) Planet migration through gas discs trapping other planets or planetesimals in resonances; (ii) Planet migration through a debris disc; (iii) Dust migration through PR drag. The Hamiltonian model will allow quick interpretation of the resonant properties of extrasolar planets and Kuiper Belt Objects, and will allow synthetic images of debris disc structures to be quickly generated, which will be useful for predicting and interpreting disc images made with ALMA, Darwin/TPF or similar missions. Full details can be found in Mustill & Wyatt (2011).
Monitoring and analyzing exoplanetary transits from Argentina
Authors: Fernández-Lajús Eduardo , Miguel Yamila , Fortier Andrea , Di Sisto Romina P. 
Published: November 2011

AbstractPhotometric observations of transits can be used to derive physical and orbital parameters of the system, like the planetary and stellar radius, orbital inclination and mean density of the star. Furthermore, monitoring possible periodic variations in transit timing of planets is important, since small changes can be caused by the presence of other planets or moons in the system. On the other hand, long term changes in the transit length can be due to the orbital precession of the planets. For these reasons we started an observational program dedicated to observe transits of known exoplanets with the aim of contributing to a better understanding of these planetary systems. In this work we present our first results obtained using the observational facilities in Argentina including the 2.15 telescope at CASLEO.
Non-convergence of the critical cooling timescale for fragmentation of self-gravitating discs
Authors: Meru Farzana , Bate Matthew R. 
Published: November 2011

AbstractWe carry out a resolution study on the fragmentation boundary of self-gravitating discs. We perform three-dimensional Smoothed Particle Hydrodynamics (SPH) simulations of discs to determine whether the critical value of the cooling timescale in units of the orbital timescale, βcrit, converges with increasing resolution. Using particle numbers ranging from 31,250 to 16 million (the highest resolution simulations to date) we do not find convergence. Instead, fragmentation occurs for longer cooling timescales as the resolution is increased. These results certainly suggest that βcrit is larger than previously thought. However, the absence of convergence also questions whether or not a critical value exists. In light of these results, we caution against using cooling timescale or gravitational stress arguments to deduce whether gravitational instability may or may not have been the formation mechanism for observed planetary systems.
A survey of M stars in the field of view of Kepler space telescope
Authors: Oshagh Mahmoudreza , Haghighipour Nader , Santos Nuno C. 
Published: November 2011

AbstractM dwarfs constitute more than 70% of the stars in the solar neighborhood. They are cooler and smaller than Sun-like stars and have less-massive disks which suggests that planets around these stars are more likely to be Neptune-size or smaller. The transit depths and transit times of planets around M stars are large and well-matched to the Kepler temporal resolution. As a result, M stars have been of particular interest for searching for planets in both radial velocity and transit photometry surveys. We have recently started a project on searching for possible planet-hosting M stars in the publicly available data from Kepler space telescope. We have used four criteria, namely, the magnitude, proper motion, H-Ks and J-H colors, and searched for M stars in Q0 and Q1 data sets. We have been able to find 108 M stars among which 54 had not been previously identified among Kepler's targets. We discuss the details of our selection process and present the results.
SKP1 is involved in abscisic acid signalling to regulate seed germination, stomatal opening and root growth in Arabidopsis thaliana
Authors: LI CHIJUN , LIU ZUOJUN , ZHANG QIRUI , WANG RUOZHONG , XIAO LANGTAO , MA HONG , CHONG KANG , XU YUNYUAN 
Published: November 2011

ABSTRACTAbscisic acid (ABA) regulates many aspects of plant development, including seed dormancy and germination, root growth and stomatal closure. Plant SKP1 proteins are subunits of the SCF complex E3 ligases, which regulate several phytohormone signalling pathways through protein degradation. However, little is known about SKP1 proteins participating in ABA signalling. Here, we report that the overexpression of Triticum aestivum SKP1‐like 1 (TSK1) in Arabidopsis thaliana (Arabidopsis) resulted in delayed seed germination and hypersensitivity to ABA. The opening of stomatal guard cells and the transcription of several ABA‐responsive genes were affected in transgenic plants. In contrast, Arabidopsis skp1‐like 1 (ask1)/ask1 ASK2/ask2 seedlings exhibited reduced ABA sensitivity. Furthermore, the transcription of ASK1 and ASK2 was down‐regulated in abi1‐1 and abi5‐1 mutants compared with that in wild type. ASK1 or ASK2 overexpression could rescue or partially rescue the ABA insensitivity of abi5‐1 mutants, respectively. Our work demonstrates that SKP1 is involved in ABA signalling and that SKP1‐like genes may positively regulate ABA signalling by SCF‐mediated protein degradation.
Animal fibre: The forgotten nutrient in strict carnivores? First insights in the cheetah
Authors: Depauw S. , Hesta M. , Whitehouse‐Tedd K. , Vanhaecke L. , Verbrugghe A. , Janssens G. P. J. 
Published: November 2011

SummaryAs wild felids are obligate carnivores, it is likely that poorly enzymatically digestible animal tissues determine hindgut fermentation, instead of plant fibre. Therefore, faecal concentrations of short‐chain fatty acids (SCFA, including branched‐chain fatty acids, BCFA), indole and phenol were evaluated in 14 captive cheetahs, fed two different diets differing in proportion of poorly enzymatically digestible animal tissue. Using a cross‐over design, the cheetahs were fed exclusively whole rabbit or supplemented beef for 1 month each. Feeding whole rabbit decreased faecal propionic (p < 0.001) and butyric (p = 0.013) acid concentrations, yet total SCFA was unaltered (p = 0.146). Also, a remarkably higher acetic acid to propionic acid ratio (p = 0.013) was present when fed whole rabbit. Total BCFA (p = 0.011) and putrefactive indole (p = 0.004) and phenol (p = 0.002) were lower when fed whole rabbit. Additionally, serum indoxyl sulphate, a toxic metabolite of indole, was analysed and showed a quadratic decrease (p = 0.050) when fed whole rabbit. The divergent SCFA ratios and the decrease in putrefaction when fed whole rabbit could be caused by the presence of undigested tissue, such as skin, bone and cartilage, that might have fibre‐like functions. The concept ofanimal fibreis an unexplored area of interest relevant to gastrointestinal health of captive cheetahs and likely other felids.
Perioperative opiate requirements in children with previous opiate infusion
Authors: Fanning Jeffrey J. , Stucke Astrid G. , Christensen Melissa A. , Cassidy Laura D. , Berens Richard J. 
Published: November 2011

SummaryBackground:  Critically ill children often require continuous opiate infusions. Tolerance may develop requiring a weaning strategy to prevent withdrawal symptoms. These children may also require subsequent surgical procedures. This is the first study to investigate whether previously opiate‐tolerant patients require higher doses of opiates for adequate pain management perioperatively.Methods:  A retrospective study was conducted at a tertiary children’s hospital to investigate whether children previously exposed to continuous opiates for 10 or more days with subsequent weaning from those opiates will have similar or increased perioperative opiate requirements when compared to opioid‐naïve controls. Study patients included 31 children with previous continuous opiate exposure for 10 or more days followed by weaning and without signs of withdrawal for at least 72 h prior to the surgical procedure. Excluded were patients over 18 years of age, those whose surgical procedures would be unlikely to require perioperative opiates, oncological patients, burn patients, neurologically devastated patients, and patients who received regional anesthesia in addition to perioperative narcotics. The control group consisted of 31 age‐ and case‐matched opiate‐naïve patients who underwent a surgical procedure during a similar time frame as the study patient. The medication administration record was reviewed for the length of continuous opiate exposure, date of last opiate use prior to a subsequent surgical procedure, and opiate use during the perioperative period. Opiate use was calculated as morphine equivalents per kilogram body weight (MSEQ·kg−1). The Wilcoxon rank sum test was used for univariate comparisons between matched pairs, and P‐values <0.05 were considered statistically significant.Results:  The perioperative opiate requirements in opiate‐exposed patients (median, interquartile range: 0.14, 0.08–0.25 MSEQ·kg−1) were not significantly different from opiate‐naïve patients (median, interquartile range 0.10, 0.05–0.2 MSEQ·kg−1, P = 0.19). Pain scores indicated that patients were generally comfortable in the perioperative period.Conclusions:  The perioperative opiate requirements of pediatric patients who were successfully weaned after prolonged opiate use were similar to opiate‐naïve patients. A history of prolonged opiate use alone does not necessitate special pain management for future procedures.