bluuebunny/crossref_metadata_2025_split huggingface dataset:
Azatryptophans as tools to study polarity requirements for folding of green fluorescent protein
Authors: Hoesl Michael Georg , Larregola Maud , Cui Haissi , Budisa Nediljko 
Published: July 2010

AbstractAequorea victoria green fluorescent protein and its widely used mutants enhanced green fluorescent protein and enhanced cyan fluorescent protein (ECFP) are ideal target proteins to study protein folding. The spectral signals of their chromophores are directly correlated with the folding status of the surrounding protein matrix. Previous studies revealed that tryptophan at position 57 (Trp57) plays a crucial role for the green fluorescent protein's structural and functional integrity. To precisely dissect its role in ECFP folding, we performed its substitution with the isosteric analogs 4‐azatryptophan [(4‐Aza)Trp] and 7‐azatryptophan [(7‐Aza)Trp]. Although Trp is moderately hydrophobic, these isosteric analogs are hydrophilic, which makes them an almost ideal tool to study the role of Trp57 in ECFP folding. We achieved high‐level expression of both (4‐Aza)Trp‐ECFP and (7‐Aza)Trp‐ECFP. However, great portions (70–90%) of protein samples were insoluble and did not contain a maturated chromophore. All attempts to refold the insoluble protein fractions failed. Nevertheless, low amounts of fully labeled, soluble, chromophore containing fractions with altered spectral features were also isolated and identified. The most probable reason for the high yield of misfolding is the introduction of strong hydrophilicity at position 57 which strongly interferes with productive and efficient folding of ECFP. In addition, the results support a strong correlation between translational kinetics of non‐canonical amino acids in the ribosome and in vivo folding of the related modified protein sequence. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Red ginseng extract improves coronary flow reserve and increases absolute numbers of various circulating angiogenic cells in patients with first ST‐segment elevation acute myocardial infarction
Authors: Ahn Chul Min , Hong Soon Jun , Choi Seung Cheol , Park Jae Hyung , Kim Jae Sang , Lim Do‐Sun 
Published: July 2010

AbstractThe effects of red ginseng extract on circulating angiogenic cell mobilization and improvement of microvascular integrity were evaluated in ST‐elevation acute myocardial infarction (AMI) patients during 8‐month follow‐up. AMI patients (n = 50) were randomly assigned to the red ginseng group (3 g/day, n = 25) or the placebo group (n = 25) after coronary stenting. Coronary flow reserve (CFR) was measured at baseline and at 8 months with an intracoronary Doppler wire. Serial changes in the absolute numbers of circulating angiogenic cells such as CD34+, CXCR4+, CD117+, CD133+ and C‐met+ were measured at baseline, 1 day, 5 days and at 8 months.CFR were similar between the two groups at baseline, and CFR was significantly higher in the red ginseng group than in the placebo group (2.80 ± 0.91 and 2.56 ± 0.77, p < 0.05, respectively) after 8 months of red ginseng administration. The absolute numbers of circulating CD34+, CXCR4+ and CD117+ cells were significantly higher in the red ginseng group at 1 and 5 days after stenting. Significant positive correlations were found between the numbers of circulating angiogenic cells at day 1 and the changes from baseline in CFR for CD34+, CXCR4+, CD117+ and C‐met+ cells. Red ginseng extract increased CD34+, CXCR4+ and CD117+ circulating angiogenic cell mobilization and decreased inflammation in AMI patients, thereby improving CFR during the 8‐month follow‐up. Copyright © 2010 John Wiley & Sons, Ltd.
Analytical expressions for entrainment and detrainment in cumulus convection
Authors: de Rooy Wim C. , Pier Siebesma A. 
Published: July 2010

AbstractAnalytical expressions for entrainment and detrainment are derived based on general total water specific humidity and mass budget equations. From these expressions, containing a small‐scale turbulent and a larger‐scale organized term, a physical picture emerges for a shallow cumulus cloud ensemble in which the individual clouds have a massive entrainment at the bottom, lateral turbulent mixing with constant mass flux between bottom and top, and massive detrainment at the top. Combining these results with the general budget equation for vertical velocity, new formulae for entrainment and detrainment rates can be expressed in terms of buoyancy, vertical velocity and cloud fraction. For a variety of shallow convection cases, results from large‐eddy simulations show a good correspondence of these new formulae with more traditional methods to diagnose entrainment and detrainment rates. Moreover, the formulae give insight into the behaviour and the physical nature of the mixing coefficients. They explain the observed large variability of the detrainment. The formulae cannot be directly applied as a parametrization. However, it is demonstrated how they can be used to evaluate existing parametrization approaches and as a sound physical base for future parametrization developments. Copyright © 2010 Royal Meteorological Society
Zap70 Functions to Maintain Stemness of Mouse Embryonic Stem Cells by Negatively Regulating Jak1/Stat3/c-Myc Signaling
Authors: Cha Young , Moon Bo-hyun , Lee Mi-ok , Ahn Hee-jin , Lee Hye-jin , Lee Kyung-ah , Fornace Albert J. , Kim Kwang-soo , Cha Hyuk-jin , Park Kyung-soon 
Published: July 2010

Abstract
Zeta-chain-associated protein kinase-70 (Zap70), a Syk family tyrosine kinase, has been reported to be present exclusively in normal T-cells, natural killer cells, and B cells, serving as a pivotal regulator of antigen-mediated receptor signaling and development. In this study, we report that Zap70 is expressed in undifferentiated mouse embryonic stem cells (mESCs) and may critically regulate self-renewal and pluripotency in mESCs. We found that Zap70 knocked-down mESCs (Zap70KD) show sustained self-renewal and defective differentiation. In addition, we present evidence that the sustained self-renewal in Zap70KD is associated with enhanced Jak/Stat3 signaling and c-Myc induction. These altered signaling appears to result from upregulated leukemia inhibitory factor receptor and downregulated src homology region 2 domain containing phosphatase 1 (SHP-1) phosphatase activity. On the basis of these results, we propose that in undifferentiated mESCs, Zap70 plays important roles in modulating the balance between self-renewal capacity and pluripotent differentiation ability as a key regulator of the Jak/Stat3/c-Myc signaling pathway.
Reflection and transmission of water waves in a two‐layer fluid flowing through a channel with undulating bed
Authors: Mohapatra S. , Bora S.N. 
Published: July 2010

AbstractWithin the framework of two‐dimensional linear water wave theory, we consider the problem of normal surface wave propagation over small undulations in a channel flow consisting of a two‐layer fluid with the upper layer bounded by a fixed wall, considered as an approximation to the free surface, and the lower one by a bottom surface which has small undulations. The effects of surface tension at the surface of separation is neglected. Assuming irrotational motion, a perturbation analysis is employed to calculate the first order corrections to the velocity potentials in the two‐layer fluid by using Fourier transform appropriately and also to calculate the reflection and transmission coefficients in terms of integrals involving the shape function c (x) representing the bottom undulation. Two special forms of the shape function are considered for which explicit expressions for reflection and transmission coefficients are evaluated. For the specific case of a patch of sinusoidal ripples having the same wave number throughout, the reflection coefficient up to the first order is an oscillatory function in the quotient of twice the interface wave number and the ripple wave number. When this quotient is one, the theory predicts a resonant interaction between the bed and the interface, and the reflection coefficient becomes a multiple of the number of ripples. But the theory breaks down at resonance and it is applicable only to infinitesimal reflection when the reflection coefficient cannot assume large value, and away from resonance. Hence, the results demonstrated here is valid for up to the near resonant cases only. Again, when a patch of sinusoidal ripples having two different wave numbers is considered, the resonant interaction between the bed and the interface attains in the neighborhood of two (singular) points along x‐axis (when the ripple wave numbers of the bottom undulation become twice as large as interface wave number). The theoretical observations are presented in graphical form.
Water‐waves modes trapped in a canal by a near‐surface rough body
Authors: Cardone G. , Durante T. , Nazarov S.A. 
Published: July 2010

AbstractThe problem about a body in a three dimensional infinite channel is considered in the framework of the theory of linear water‐waves. The body has a rough surface characterized by a small parameter ε > 0 while the distance of the body to the water surface is also of order ε. Under a certain symmetry assumption, the accumulation effect for trapped mode frequencies is established, namely it is proved that, for any given d > 0 and integer N > 0, there exists a number ε (d, N) > 0 such that the problem has at least N eigenvalues in the interval (0, d) of the continuous spectrum in the case ε ∈ ( 0, ε (d, N)). The corresponding eigenfunctions decay exponentially at infinity, have finite energy, and imply trapped modes.
Autologous bone marrow cell infusion therapy for liver cirrhosis patients
Authors: Terai Shuji , Sakaida Isao 
Published: July 2010

AbstractWe developed a novel cell therapy, autologous bone marrow cell infusion (ABMi) therapy, using autologous bone marrow, for liver cirrhosis patients. Our study depends on the findings from basic studies that bone marrow cell infusion repairs liver fibrosis in the cirrhotic liver, and improves liver function and the survival rate. Beginning in November 2003, we started a clinical study and found that ABMi therapy was safe and effective for liver cirrhosis patients. Multicenter trials in Japan and Korea have also shown the effectiveness of ABMi therapy. In this review, we report the current status of ABMi therapy for liver cirrhosis patients.
Solvent Extraction: Kinetic Study of Major and Minor Compounds
Authors: Baümler Erica R. , Crapiste Guillermo H. , Carelli Amalia A. 
Published: July 2010

AbstractThe effects of temperature and contact time on lipid extraction from sunflower collets was investigated in a batch extractor with hexane as solvent. The total removed material varied in quantity and composition due to changes in temperature and contact time. Higher temperatures enhanced oil extraction as well as increased the tocopherol and phospholipid contents of the oil. The kinetic data for triglycerols, phospholipid and tocopherols extraction were interpreted by using an equation that considers extraction as the sum of two components: diffusion and washing. Effective diffusion coefficients for oil, tocopherols and phospholipid at different temperatures were determined. Control of temperature and contact time are essential to obtain good quality oil and reduce refining costs. Extraction at 60 °C and short contact times (30 min) obtained high oil yield (98%) accompanied by significant tocopherol extraction (>99%) and reduced phospholipid extraction (66%).
Host species critical for offspring fitness and sex ratio for an oligophagous parasitoid: implications for host coexistence
Authors: Stenberg J.A. , Hambäck P.A. 
Published: July 2010

AbstractIn theory, inferior apparent competitors sharing a natural enemy with superior apparent competitors should be excluded in the absence of stabilising factors. Nevertheless, plentiful examples of coexisting apparent competitors exist. In this paper, we show that parasitoid resource competition within hosts affects both parasitoid sex ratio and female body size, with implication for population growth and apparent competition between the two closely related hosts experiencing a strong asymmetry in their interaction. While the superior competitor delivers parasitoids with higher fitness to the shared parasitoid pool, the inferior competitor delivers a higher proportion of female parasitoids. Hence, the inferior host experience an inflow of fit parasitoids from the superior competitor, which should increase the risk of exclusion, but also an outflow of parasitoid females, which should reduce the risk of exclusion and increase stability. We conclude that differential outcomes of parasitoid resource competition in different host species may have profound effects on shared parasitoid populations and should be included in future studies of apparent competition between hosts.
Feeding ecology of the Brazilian silversideAtherinella brasiliensis(Atherinopsidae) in a sub-tropical estuarine ecosystem
Authors: Contente R.F. , Stefanoni M.F. , Spach H.L. 
Published: July 2010

The feeding ecology of the Brazilian silverside,Atherinella brasiliensis, in a sub-tropical estuary of Brazil was investigated through the gut analysis of 1431 individuals. We described dietary composition and analysed seasonal, estuarine habitat, and body size variations in the diet; trophic level; feeding diversity; and gut fullness indices. Results reveal thatA. brasiliensisis a typical, generalistic and opportunistic predator that makes use of a wide array of prey types (at least 89 different types), with zooplankton (mainly calanoids), diatoms, terrestrial insects, and plant detritus making up the bulk of the overall diet. The exotic calanoidTemora turbinataranked as the primary prey. A wide feeding diversity (meanH′ = 2.26), low trophic level (meanTROPH = 2.57), and high gut replenishment were persistent across seasons and habitats. Diet composition varied largely and significantly with respect to habitat, season, and body size. A closer assessment showed that habitat and season had a stronger effect on diet than fish size.
Spatial aggregation patterns of free-living marine nematodes in contrasting sandy beach micro-habitats
Authors: Gingold Ruth , Ibarra-Obando Silvia E. , Rocha-Olivares Axayácatl 
Published: July 2010

In the absence of chemical or physical gradients, random displacement of organisms can result in unpredictable distribution patterns. In spite of a limited locomotive capability, marine nematodes may choose where to settle after re-suspension and may maintain their position in the sediment under calm conditions, leading to small-scale (<1 m) spatial variability. However, in more energetic environments, nematodes become re-suspended with sediments and re-distributed at distances dependent on prevalent hydrodynamic regimes, from metre- to decametre-scale or more. In this study, we tested the hypothesis that micro-habitats (i.e. runnels and sandbars) in a macrotidal sandy beach influence the distribution patterns of free-living marine nematodes by exhibiting contrasting hydrodynamic regimes. Specifically, we predicted patchier distributions in the calmer environment (runnel). We sampled nematodes in each habitat from <1 m to decametre scales. Our results show more heterogeneous spatial distributions in the runnel, presumably owing to a predominance of active displacement under calmer conditions and sediment cohesion by algal films. Biological similarity among runnel replicates was low, whereas replicates from the sandbar exhibited higher similarity, presumably because of homogenization of the sediment and inhabiting fauna by tidal currents. A significant negative correlation between biological similarity and sampling distance was found in the runnel, but not in the sandbar. The most similar samples were the closest in the runnel and the most distant in the sandbar. More patchily distributed taxa were found in the runnel and a larger fraction of homogeneously or randomly distributed taxa in the sandbar. We conclude that different hydrodynamic regimes in contrasting intertidal micro-habitats significantly influenced the nematofaunal distribution, resulting in different spatial patterns next to one another in the same beach. This has significant implications for sampling and monitoring designs and begs the need for detailed studies about the physical and biological processes governing meiobenthic communities.
Neuroendocrine features of attachment in infants and nonhuman primates
Authors: Seltzer Leslie J. , Pollak Seth D. 
Published: July 2010

AbstractThe translation of research findings from other primates to humans, and from infants to adults within our own species, requires great care. If the many neurological, behavioral and adaptive distinctions between these groups are not precisely defined and considered, erroneous conclusions about evolutionary history and developmental processes may result.
The impact of individual quotas on technical efficiency: does quality matter?
Authors: DRESDNER JORGE , CAMPOS NÉLYDA , CHÁVEZ CARLOS 
Published: July 2010

ABSTRACTWe estimate the technical efficiency gains of introducing individual quotas (IQs) in fisheries. Our estimates are based on two samples of vessels, considering a potential self-selection bias and controlling for quality changes in landings induced by the IQ system. The results suggest that the introduction of IQs has an important positive impact on fleet efficiency, and that properly measuring this impact requires controlling for the self-selection bias and quality changes induced by the regulatory shift.
Climate change and its impacts: growing stress factors for human societies
Authors: Beniston Martin 
Published: July 2010

AbstractThe realization that human beings need to be concerned about the only ‘life-support system’ that the Earth and its environment provides stems perhaps in part from the fact that, until fairly recently, the evolution of humankind was largely dependent on the quality of the environment and the resources it provides in terms of water, food, and favourable health conditions. These are as vital as ever, despite current levels of technology and apparent resilience in the face of often degraded environments in many parts of the world. Today, the conditions for human sustainability (i.e. water quality and quantity, food security, and health) are potentially under threat as a result of numerous human-induced factors; among these, climate change is certainly one of the more durable aspects of anthropogenic disruptions to natural resources. This article will therefore focus on the possible evolution of climate in the course of the twenty-first century and on a number of key climate impacts that may determine the future course of human societies, as well as issues that may confront them such as rivalries over natural resources and possible environmentally driven conflicts and migrations.
Axon‐to‐glia signalling is mediated by n‐acetylaspartylglutamate (NAAG) in crayfish
Authors: Lieberman E. M. , Urazaev A. K. , Fletcher P. L. , Gafurov B. S. , Grossfeld R. M. 
Published: July 2010

Action potential generation in the medial giant axon of the crayfish causes the associated periaxonal glia to hyperpolarize by mechanisms sensitive to metabotropic glutamate receptor (mGLUR) and cholinergic receptor blockade. This response can be mimicked by the application of nanomolar NAAG or glutamate (GLU). Axons and glia synthesize NAAG from GLU or glutamine (GLN) and release it during electrical stimulation of the axon. NAAG is hydrolyzed to N‐acetylaspartate and GLU by glutamate carboxypeptidase II (GCPII), whose activity is increased by nerve fiber stimulation. When GCPII activity is blocked pharmacologically, NAAG's electrophysiological action on the glia is mediated solely by Group II mGLURs. When the enzyme is activated, GLU, the hydrolysis product of NAAG, contributes to glial hyperpolarization through a mechanism sensitive to NMDA receptor blockade. Both NAAG and GLU cause an increase in glial Ca2+ that may be a common link to a transduction cascade that hyperpolarizes glia by reducing Cl– permeability. A consequence of these changes is the modulation of K+ homeostasis of the neuronal microenvironment, preserving the ability of the axon to generate impulses at high frequency. GLU formed by NAAG hydrolysis is avidly accumulated by periaxonal glia, where it is converted to GLN and NAAG. The uptake of GLN and conversion to GLU and NAAG by axons provides a possible mechanism for recycling of the axon‐to‐glia signalling agent(s) in crayfish nerve fibers. Together, these results suggest that NAAG is the primary axon‐to‐glia signalling agent and source of signalling GLU at nonsynaptic regions of crayfish nerve fibers.Acknowledgements:  Supported by NIH grant NS34799 and Guilford Pharmaceuticals (Baltimore, MD).
CIP98, a novel PDZ domain protein, is expressed in the central nervous system and interacts with calmodulin‐dependent serine kinase
Authors: Yap Chan Choo , Liang Fengyi , Yamazaki Yasuhiro , Muto Yuko , Kishida Haruo , Hayashida Tsuyako , Hashikawa Tsutomu , Yano Ryoji 
Published: July 2010

AbstractReceptors and various molecules in neurons are localized at precise locations to perform their respective functions, especially in synaptic sites. Among synaptic molecules, PDZ domain proteins play major roles in scaffolding and anchoring membrane proteins for efficient synaptic transmission. In the present study, we isolated CIP98, a novel protein (98 kDa) consisting of three PDZ domains and a proline‐rich region, which is widely expressed in the central nervous system. In situ hybridization and immunohistochemical staining patterns demonstrate that CIP98 is expressed strongly in certain types of neurons, i.e. pyramidal cells in layers III–V of the cerebral cortex, projecting neurons in the thalamus and interneurons in the cerebellum. The results of immunocytochemical staining and electron microscopy revealed that CIP98 is localized both in dendrites and axons. Interestingly, CIP98 interacts with CASK (calmodulin‐dependent serine kinase), a member of the membrane‐associated guanylate kinase (MAGUK) family that plays important roles in the molecular organization of proteins at synapses. CIP98 was shown to co‐localize with CASK along the dendritic processes of neurons. In view of its direct association with CASK, CIP98 may be involved in the formation of CASK scaffolding proteins complex to facilitate synaptic transmission in the CNS.
Dephosphorylation of pCREB by protein serine/threonine phosphatases is involved in inactivation ofAanatgene transcription in rat pineal gland
Authors: Koch Marco , Mauhin Viviane , Stehle Jörg H. , Schomerus Christof , Korf Horst‐Werner 
Published: July 2010

AbstractThe rat pineal gland is a suitable model to investigate neurotransmitter‐controlled gene expression, because it is well established that the stimulation of melatonin biosynthesis by norepinephrine (NE) depends on the activation of the gene that encodes arylalkylamineN‐acetyltransferase (AANAT), the melatonin rhythm enzyme. The mechanisms responsible for downregulation ofAanattranscription are less clear. In thisin vitrostudy we investigated the role of pCREB dephosphorylation for termination ofAanatgene transcription. Immunosignals for pCREB, strongly induced after NE stimulation, rapidly decreased after withdrawal of NE. The immunoreactivity of the inhibitory transcription factor ICER increased twofold after NE treatment for 6 h, but did not change within 30 min after removal of the stimulus. Application of protein serine/threonine phosphatase (PSP) inhibitors prevented pCREB dephosphorylation and blocked the decreases inAanatmRNA levels, AANAT protein amount and melatonin biosynthesis all of which occurred rapidly after NE withdrawal. PSPs in the rat pineal gland were characterized by immunocytochemistry and immunoblotting. NE‐stimulation for 8 h induced accumulation of PSP1‐catalytic subunit (CSU) in pinealocyte nuclei, but did not affect the distribution of PSP2A‐CSU. The results identify dephosphorylation of pCREB by PSPs as an essential mechanism for downregulation ofAanattranscription in the rat pineal gland.