bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Geo‐Electric Field Variation of Sichuan Lushan MS7.0 and Wenchuan MS8.0 Earthquake
Authors: Zhang‐Hui AN , Xue‐Bin DU , Da‐Cheng TAN , Ying‐Ying FAN , Jun LIU , Teng‐Fa CUI
Published: February 2014

Applying the data of geo‐electric field observation stations surrounding the epicenter of Sichuan Lushan Ms7.0 and Wenchuan Ms8.0 earthquake, mainly using electric field waveform comparison and polarization orientation changes of two kinds of methods, and combining the observation log of stations, we study and analyze the data of the geo‐electric field station before the two earthquakes and conclude that, the anomalous waveform variation before the Lushan Ms7.0 and Wenchuan Ms8.0 earthquake showed mainly two forms: diurnal waveform distortion (such as Yanyuan station and Lugu Hu station) and the change of geo‐electric field frequency spectrum characteristics in the corresponding time, and these variations basically appeared in 1∼2 months before the earthquake. Using the daily mean value of geo‐electric field observed by part of stations around the epicenter of two earthquakes, we calculated the polarization of geo‐electric field before two earthquakes, and found a sharp change in the polarization direction before the earthquake, the largest change was 160°, and the minimum change was 10°. A preliminary study also found that, before the two earthquakes, the intersection region of the forward or reverse extension line of polarization orientation and the epicenter seem to have some sort of connection. For the results obtained in this study, a tentative theoretical explanation was given based on the generation mechanism of seismic electric signals and the focal mechanism of the two earthquakes.
On Near‐Fault Ground Motion Characteristics Through Multi‐Scale Method
Authors: Guo‐Chen ZHAO , Long‐Jun XU , Li‐Li XIE
Published: February 2014

Ground motion recorded in near‐fault regions that possesses long‐period pulse is a special destructive ground motion. For further research on the constituent of low‐frequency component and its pulse characteristics, a decomposition method based on multi‐scale analysis method in wavelet theory is proposed. Accordingly, an intact ground motion can be decomposed into multiple components having different frequency contents. Firstly, the validity and accuracy of this decomposition method are elaborated in three aspects which are the frequency domain, time domain and the dynamic response. Secondly, a suite of 53 typical near‐fault ground motions recorded from 12 recent major earthquakes are decomposed through this method, then a total of 266 ground motion components are obtained. Thirdly, a quantitative statistical study of the variation of the long period components contained in near‐fault ground motions with the impact of site and rupture distance is carried out in this paper. Lastly, predominant component is used as the simplified model of dominant pulse, and the variation of velocity amplitude and pulse period with the impact of magnitude and rupture distance is presented. It is concluded that: the period of the component which is the main ingredient of near‐fault ground motions is within 0.2∼2 s; the long‐period component contained in soil ground motions is richer than in rocks; in near‐fault area where the rupture distance is 0∼15 km, the proportion of the long period component decreases along with rupture distance increase; PGVp, the velocity amplitude of predominant component, is about 0.6 times of PGV, the velocity amplitude of original ground motion, and a clear linear relation is found between them; PGVp decreases as rupture distance increases, and will be larger in great earthquakes; logarithm of the pulse periods Tp increases linearly as magnitude increases.
Characteristics and Mechanisms of Rock Magnetic Enhancement in Underground Coal Spontaneous Combustion Areas—Examples of the Wuda Coal Mine of Inner Mongolia and Rujigou Coal Mine in Ningxia
Authors: Sheng‐Qing XIONG , Chang‐Chun YU
Published: February 2014

The temperature experiment and lithologic analysis were conducted on the samples obtained in the underground coal spontaneous combustion areas to study the mechanisms how rock magnetism changes with temperature. The samples were tested at different temperatures to analyze the characteristics and changing rules of the magnetic value, iron‐containing oxide percentage and structure. The results show that temperature change can cause variation of magnetism, which is very small below 400°C, and increases with temperature before it reaching the Curie temperature. Magnetism of the samples vanishes when the temperature is beyond the Curie temperature. Magnetism of samples increases obviously when they are cooled below the Curie temperature, and is higher than being heated before. The changes of magnetism are primarily related with mineral content and structure in iron‐containing oxides, such as pyrite, hematite, siderite, and limonite. The content of ferromagnetic mineral in rock samples increases obviously by heating samples to 700°C and cooling it to normal temperature. The structure of mineral is variable in the experiment and the size of particle is smaller than the before as well. Generally, the particle size is 10∼150 μm which belongs to multi‐domain structure (MD), some of which belongs to single‐domain structure. The main reason for magnetism enhancement is that new ferromagnetic minerals (pyrite, hematite, siderite, limonite etc.) are created from few iron‐contained minerals when the temperature is increased. The research results above are significant to explain magnetic anomalies in coal spontaneous combustion areas.
Influence of paramagnetic melanin on the MRI contrast in melanoma: a combined high‐field (11.7 T) MRI and EPR study
Authors: Godechal Q. , Mignion L. , Karroum O. , Magat J. , Danhier P. , Morandini R. , Ghanem G. E. , Leveque P. , Gallez B.
Published: February 2014

Melanoma is the most dangerous form of skin cancer and its incidence is rising each year. Because the current methods of diagnosis based on the visual aspect of the tumor show limitations, several new techniques are emerging to help in this diagnosis, amongst which are magnetic resonance imaging (MRI) and electron paramagnetic resonance (EPR). The origin of the typical contrast pattern observable in melanoma in T1‐ and T2‐weighted images remains to be elucidated and is a source of controversy. In addition, melanin could create sufficient magnetic inhomogeneities to allow its visualization on T2*‐weighted images using high‐field MRI. In order to elucidate the possible role of melanin in the MRI contrast of melanoma, the present study was designed to correlate the paramagnetic content in melanin pigment to the contrast on T1‐, T2‐ and T2*‐weighted images. MR images were obtained in vivo at 11.7 T using four types of experimental tumors with different pigmentations (B16, HBL, LND1 melanomas and KHT sarcomas). The paramagnetic content in melanin pigment was measured by EPR. No significant correlation was observed between the content in melanin and the relaxation times T1, T2 and T2*, emphasizing that the presence of pigment alone has negligible effect on the MRI contrast. Copyright © 2014 John Wiley & Sons, Ltd.
National trends in prostate cancer screening among older American men with limited 9‐year life expectancies: Evidence of an increased need for shared decision making
Authors: Drazer Michael W. , Prasad Sandip M. , Huo Dezheng , Schonberg Mara A. , Dale William , Szmulewitz Russell Z. , Eggener Scott E.
Published: February 2014

BACKGROUND

Prostate‐specific antigen (PSA) screening for prostate cancer remains controversial. Most groups recommend informed decision making for men with 10 years of remaining life expectancy. The primary objective of this observational cohort study was to investigate the association between predicted 9‐year mortality and prostate cancer screening among American men aged ≥65 years in 2005 and 2010. The second objective was to analyze the proportions of men who discussed screening with their physicians.

METHODS

Data were extracted from the 2005 and 2010 National Health Interview Surveys. Men aged ≥65 years without prostate cancer were divided into predicted 9‐year mortality quartiles. The proportions of men confirming a screening PSA within the prior year were determined. Logistic regression was used to compare screening rates.

RESULTS

Screening rates for men aged ≥65 years were 48% in 2005 and 48% in 2010 (P = .9). Men ages 65 to 74 years who had <27% predicted 9‐year mortality were most commonly screened, with 56% screened in 2010, compared with 34% of men aged ≥75 years with >75% predicted 9‐year mortality. Approximately 55% of screened men aged ≥75 years who had ≥53% predicted 9‐year mortality recalled discussing the advantages of screening, whereas 25% recalled discussing the disadvantages.

CONCLUSIONS

Prostate cancer screening with PSA did not differ significantly between 2005 and 2010 for men aged ≥65 years based on predicted 9‐year mortality. Approximately 33% of older men with a high likelihood of 9‐year mortality were screened despite minimal clinical benefit. Twice as many men recalled discussing the potential advantages of screening compared with the disadvantages. Cancer 2014;120:1491–1498. © 2014 American Cancer Society.
Adenosine triphosphate‐induced photoreceptor death and retinal remodeling in rats
Authors: Vessey Kirstan A. , Greferath Ursula , Aplin Felix P. , Jobling Andrew I. , Phipps Joanna A. , Ho Tracy , De Iongh Robbert U. , Fletcher Erica L.
Published: February 2014

Many common causes of blindness involve the death of retinal photoreceptors, followed by progressive inner retinal cell remodeling. For an inducible model of retinal degeneration to be useful, it must recapitulate these changes. Intravitreal administration of adenosine triphosphate (ATP) has recently been found to induce acute photoreceptor death. The aim of this study was to characterize the chronic effects of ATP on retinal integrity. Five‐week‐old, dark agouti rats were administered 50 mM ATP into the vitreous of one eye and saline into the other. Vision was assessed using the electroretinogram and optokinetic response and retinal morphology investigated via histology. ATP caused significant loss of visual function within 1 day and loss of 50% of the photoreceptors within 1 week. At 3 months, 80% of photoreceptor nuclei were lost, and total photoreceptor loss occurred by 6 months. The degeneration and remodeling were similar to those found in heritable retinal dystrophies and age‐related macular degeneration and included inner retinal neuronal loss, migration, and formation of new synapses; Müller cell gliosis, migration, and scarring; blood vessel loss; and retinal pigment epithelium migration. In addition, extreme degeneration and remodeling events, such as neuronal and glial migration outside the neural retina and proliferative changes in glial cells, were observed. These extreme changes were also observed in the 2‐year‐old P23H rhodopsin transgenic rat model of retinitis pigmentosa. This ATP‐induced model of retinal degeneration may provide a valuable tool for developing pharmaceutical therapies or for testing electronic implants aimed at restoring vision. J. Comp. Neurol. 522:2928–2950, 2014. © 2014 Wiley Periodicals, Inc.
Accurate cross‒architecture performance modeling for sparse matrix‒vector multiplication (SpMV) on GPUs
Authors: Guo Ping , Wang Liqiang
Published: February 2014

This paper presents an integrated analytical and profile‒based cross‒architecture performance modeling tool to specifically provide inter‒architecture performance prediction for Sparse Matrix‒Vector Multiplication (SpMV) on NVIDIA GPU architectures. To design and construct the tool, we investigate the inter‒architecture relative performance for multiple SpMV kernels. For a sparse matrix, based on its SpMV kernel performance measured on a reference architecture, our cross‒architecture performance modeling tool can accurately predict its SpMV kernel performance on a target architecture. The prediction results can effectively assist researchers in making choice of an appropriate architecture that best fits their needs from a wide range of available computing architectures. We evaluate our tool with 14 widely‒used sparse matrices on four GPU architectures: NVIDIA Tesla C2050, Tesla M2090, Tesla K20m, and GeForce GTX 295. In our experiments, Tesla C2050 works as the reference architecture, the other three are used as the target architectures. For Tesla M2090, the average performance differences between the predicted and measured SpMV kernel execution times for CSR, ELL, COO, and HYB SpMV kernels are 3.1%, 5.1%, 1.6%, and 5.6%, respectively. For Tesla K20m, they are 6.9%, 5.9%, 4.0%, and 6.6% on the average, respectively. For GeForce GTX 295, they are 5.9%, 5.8%, 3.8%, and 5.9% on the average, respectively. Copyright © 2014 John Wiley & Sons, Ltd.
Data resource discovery model based on hybrid architecture in data grid environment
Authors: Ma Tinghuai , Lu Yinhua , Shi Sunyuan , Tian Wei , Wang Xin , Guan Donghai
Published: February 2014

Today, the management of massive data collections draws much attention as data grids have been developed to deal with large computational problems and provide the opportunity for sharing geographically distributed resources for large‒scale data‒intensive applications. Therefore, finding an effective approach to discover data resources in order to promote better interactions between application communities or virtual organizations becomes a critical challenge. Traditional grid resource discovery models are mostly based on central and hierarchical architecture that can lead to bottlenecking with the expansion of the grid scale. Although the Peer‒to‒Peer (P2P) technique is integrated into the grid in order to improve the performance in recent years, each P2P structure still has drawbacks that require several compensatory strategies. In this paper, based on the unstructured super‒node‒based architecture from the P2P system, we design a structured logic resource tree in each domain in order to effectively alleviate the load on the super‒node, and we propose a query recording learning algorithm based on this hybrid architecture to reduce traffic in the network and greatly shorten the response time. The model and algorithm are validated by simulations and compared with the traditional super‒peer model and the flooding‒based approach. Copyright © 2014 John Wiley & Sons, Ltd.
High‐performance gas‐sensing properties of octahedral NiO crystals prepared via one‐step controllable synthesis route
Authors: Lv Yaohui , Huang Kai , Zhang Wei , Ran Songlin , Chi Fangli , Yang Bin , Liu Xianguo
Published: February 2014

Octahedrally shaped NiO powders have been synthesized via a one‐step composite‐hydroxide‐mediated method without any surfactant. The synthesized materials are characterized by XRD, EDS, TEM and FESEM techniques. Each particle exhibited a nearly perfect octahedron shape with sharp edges and corners as well as smooth surfaces. The octahedral NiO particles performed better gas‐sensitivity toward ethanol than that of NiO nanopowders, which was attributed to the exposed ｛111｝ facets of octahedron. The result was confirmed by the first‐principle calculation which indicated that the (111) facet was more active than (100) and (110) facet.
Frequency resource allocation strategy with QoS support in hybrid cellular and Device‐to‐Device networks
Authors: Wang Zhibo , Tian Hui , Yang Kun , Liu Ziqiang
Published: February 2014

Hybrid networks, comprising a conventional cellular network overlaid with Device‐to‐Device (D2D), offer efficient way to improve system throughput. In this paper, a novel orthogonal frequency‐division multiple access channel‐assignment method is proposed for hybrid network. The proposed approach is optimal in terms of throughput and is subjected to a sensible QoS requirement, which guarantees that macrocell and D2D achieve a prescribed data rate and outage probability, respectively. Our solution consists of two phases. In the first phase, the minimum sub‐channels are allocated to the macrocell to satisfy their data rate requirements. This problem is mapped to the 0‐1 Knapsack Problem and solved by integer programming based Lagrange dual approach. In the second phase, the redundant sub‐channels are allocated to D2D pairs to maximize the throughput of D2D networks. An interference management scheme is proposed to guarantee the outage probability of D2D communications. A cluster is taken as the unit for frequency reuse among D2D pairs. The problem of clustering is mapped to the MAX k‐CUT problem in graph theory and is solved by graph‐based heuristic algorithm. Extensive simulations demonstrate the superior performance of the proposed solution compared with the existing scheme. Copyright © 2014 John Wiley & Sons, Ltd.
Nutrients other than carbohydrates: their effects on glucose homeostasis in humans
Authors: Heer Martina , Egert Sarah
Published: February 2014

Besides carbohydrates, other nutrients, such as dietary protein and amino acids; the supply of fat, vitamin D, and vitamin K; and sodium intake seem to affect glucose homeostasis. Although their effect is less pronounced than that of the amount and composition of carbohydrates, it seems reasonable to consider how nutrient intake habits may be modified to support an improved glucose homeostasis. For instance, taking into account the effect of some nutrients to lower blood glucose concentration on a day‐by‐day basis might support improvement of glucose homeostasis in the long run. On the other hand, lowering sodium intake too much, as recommended to avoid the development of hypertension, particularly in sodium‐sensitive people, might lead to insulin resistance and thereby might risk increasing fasting as well as postprandial blood glucose concentrations. This review summarizes the state of our knowledge of how several nutrients other than carbohydrates, such as protein, fatty acids, vitamin D, vitamin K, magnesium, zinc, chromium, and sodium, affect blood glucose concentrations. Sufficient evidence exists to show that, in prospective studies based on randomized controlled trials, these selected nutrients affect blood glucose regulation. The review describes potential mechanisms leading to the observed effect. As much as is possible from the available data, the extent of the effect, is considered. Copyright © 2014 John Wiley & Sons, Ltd.
Growth factors and early mesoderm morphogenesis: Insights from the sea urchin embryo
Authors: Adomako‐Ankomah Ashrifia , Ettensohn Charles A.
Published: February 2014

The early morphogenesis of the mesoderm is critically important in establishing the body plan of the embryo. Recent research has led to a better understanding of the mechanisms that underlie this process, and growth factor signaling pathways have emerged as key regulators of the directional movements of mesoderm cells during gastrulation. In this review, we undertake a comparative analysis of the various essential functions of growth factor signaling pathways in regulating early mesoderm morphogenesis, with an emphasis on recent advances in the sea urchin embryo. We focus on the roles of the vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) pathways in the migration of primary mesenchyme cells and the formation of the embryonic endoskeleton. We compare the functions of VEGF and FGF in sea urchins with the roles that these and other growth factors play in regulating mesoderm migration during gastrulation in Drosophila and vertebrates. genesis 52:158–172. © 2014 Wiley Periodicals, Inc.
Plasticity of source‐water acquisition in epiphytic, transitional and terrestrial growth phases of Ficus tinctoria
Authors: Liu Wenjie , Wang Pingyuan , Li Jintao , Liu Wenyao , Li Hongmei
Published: February 2014

Despite continued studies on the ecology and physiology of strangling hemiepiphytes, there is little quantitative information about the variations in source‐water uptake by these species under different growth phases. In this study, the water acquisition patterns of a hemiepiphyte, Ficus tinctoria, is investigated in relation to growth phase (epiphytic, transitional and terrestrial) and season (foggy, hot‐dry and rainy). Stable isotope compositions of water in xylem, soil, canopy humus, fog and rainfall were sampled on seasonally distinct dates, and soil water content and leaf carbon isotope composition were measured in order to determine the proportion of different water sources. Results indicated that F. tinctoria displayed a high degree of plasticity in source‐water acquisition associated with the growth‐phase transition from purely canopy‐rooted epiphyte to transitional plant to terrestrial tree. During the foggy season and the hot‐dry season, epiphytes utilized a combination of recently received rainwater (82–89%) and fog water (11–18%) present in canopy humus soil, whereas terrestrial trees exclusively depended on shallow and deep terrestrial soil water and exhibited marked flexibility in depth of soil water uptake. Transitional‐phase plants relied predominantly on shallow soil water (79–86%) and extracted only a small fraction of canopy humus water (14–21%). During the rainy season, epiphytes relied almost exclusively on recent rainwater (96%) and had a negligible water uptake from fog, whereas trees extracted their water primarily from the shallow soil and less from the deep soil. Plants in transitional‐phase drew a considerable fraction of water from canopy humus soil. This plasticity of source‐water uptake to cope with radical changes in rooting environment is likely the key feature enabling hemiepiphytic species to thrive and successfully establish in the tropical rainforests. Copyright © 2014 John Wiley & Sons, Ltd.
Japanese encephalitis virus expands regulatory T cells by increasing the expression of PD‐L1 on dendritic cells
Authors: Gupta Nimesh , Hegde Pushpa , Lecerf Maxime , Nain Minu , Kaur Manpreet , Kalia Manjula , Vrati Sudhanshu , Bayry Jagadeesh , Lacroix‐Desmazes Sébastien , Kaveri Srini V.
Published: February 2014

The mechanisms underlying Japanese encephalitis virus (JEV) pathogenesis need to be thoroughly explored to delineate therapeutic approaches. It is believed that JEV manipulates the innate and adaptive compartments of the host's immune system to evade immune response and cross the blood–brain barrier. The present study was thus designed to investigate the functional modulation of DCs after exposure to JEV and to assess the consequences on CD4+ T‐lymphocyte functions. Human monocyte‐derived DCs were either infected with 1 MOI of live virus, UV‐inactivated virus, or were mock‐infected. Replication‐competent JEV induced a significant increase in the expression of maturation markers 48 h postinfection, along with that of programmed cell death 1 ligand 1 (PD‐L1; also called B7‐H1 and CD274). JEV‐infected DCs expanded the Treg cells in allogenic mixed lymphocyte reactions. The expansion of Treg cells by JEV‐infected DCs was significantly reduced upon blocking PD‐L1 using an antagonist. In addition, JEV‐infected DCs significantly altered the proliferation and reduced the polarization of Th cells toward the Th1‐cell phenotype. The results, for the first time, suggest that JEV evades the host's immune system by modulating the crosstalk between DCs and T lymphocytes via the PD‐L1 axis.
Gimap and T cells: A matter of life or death
Authors: Ciucci Thomas , Bosselut Rémy
Published: February 2014

GTPase immune‐associated proteins (Gimap) genes encode evolutionarily conserved GTP‐binding proteins that are preferentially expressed in immune cells. Specific members have been shown to be involved in lymphocyte development, or are associated with inflammatory and autoimmune diseases. However, the function of these proteins remains poorly understood, both at the cellular and molecular levels. A new study in this issue of the European Journal of Immunology [Eur. J. Immunol. 2014. 44: 561–572] points to the distinct but partly overlapping functions of two members of this family, Gimap3 and Gimap5, and offers new insight into their potential functions in T cells.
Tailoring Peptide–Nucleotide Conjugates (PNCs) for Nucleotide Delivery in Bacterial Cells
Authors: De Swarup , Groaz Elisabetta , Herdewijn Piet
Published: February 2014

The design and synthesis of peptide‐2′‐deoxythymidine‐5′‐O‐monophosphate conjugates as potential active delivery systems for nucleotides into auxotrophic E. coli strains is presented. A series of oligopeptides were allowed to react with 5′‐O‐(dibenzylphosphate)‐2′‐deoxythymidine or its suitably 3′‐derivatized analogues to give the relevant peptide–nucleotide adducts, by the formation of a biolabile chemical connection. Using strategies based on the principles of orthogonal protection and activation, rational variations were made to the linker and the peptide moiety in order to tune the metabolic stability of the conjugates.
High Yield SNAr on 8‐Halogenophenyl‐BODIPY with Cyclic and Acyclic Polyamines
Authors: Volkova Yulia , Brizet Bertrand , Harvey Pierre D. , Denat Franck , Goze Christine
Published: February 2014

Selective nucleophilic aromatic substitutions with several polyamines were performed in very good yields on halogeno‐phenyl BODIPY derivatives containing an activating nitro group.
Anionic microemulsion to solvent stacking for on‐line sample concentration of cationic analytes in capillary electrophoresis
Authors: Kukusamude Chunyapuk , Srijaranai Supalax , Quirino Joselito P.
Published: February 2014

The common SDS microemulsion (i.e. 3.3% SDS, 0.8% octane, and 6.6% butanol) and organic solvents were investigated for the stacking of cationic drugs in capillary zone electrophoresis using a low pH separation electrolyte. The sample was prepared in the acidic microemulsion and a high percentage of organic solvent was included in the electrolyte at anodic end of capillary. The stacking mechanism was similar to micelle to solvent stacking where the micelles were replaced by the microemulsion for the transport of analytes to the organic solvent rich boundary. This boundary is found between the microemulsion and anodic electrolyte. The effective electrophoretic mobility of the cations reversed from the direction of the anode in the microemulsion to the cathode in the boundary. Microemulsion to solvent stacking was successfully achieved with 40% ACN in the anodic electrolyte and hydrodynamic sample injection of 21 s at 1000 mbar (equivalent to 30% of the effective length). The sensitivity enhancement factors in terms of peak height and corrected peak area were 15 to 35 and 21 to 47, respectively. The linearity R2 in terms of corrected peak area were >0.999. Interday precisions (%RSD, n = 6) were 3.3–4.0% for corrected peak area and 2.0–3.0% for migration time. Application to spiked real sample is also presented.
Buffer salt effects in off‐line coupling of capillary electrophoresis and mass spectrometry
Authors: Marák Jozef , Staňová Andrea
Published: February 2014

In this work, the impact of buffer salts/matrix effects on the signal in direct injection MS with an electrospray interface (DI‐ESI‐MS) following pITP fractionation of the sample was studied. A range of buffers frequently used in CE analyses (pH 3–10) was prepared containing 10, 50, and 90% v/v of ACN, respectively. The sets of calibration solutions of cetirizine (an antihistaminic drug with an amphiprotic character) within a 0.05–2.0 mg/L concentration range were prepared in different buffers. The greatest enhancements in the MS signal (in terms of change in the slope of the calibration line) were obtained for the beta‐alanine buffer (pH 3.5) in positive ionization and for the borate buffer (pH 9.2) in negative ionization, respectively. The procedure was successfully applied to the analysis of buserelin (a peptidic drug). The slope of the calibration line for solutions containing the beta‐alanine buffer with 50% of ACN was 4 times higher than for water or urine, respectively. This study clearly demonstrates that the buffer salt/matrix effects in an off‐line combination of pITP and DI‐ESI‐MS can also play a positive role, as they can enhance the signal in MS. A similar influence of the above effects can also be presumed in the CE techniques combined on‐line with ESI‐MS.
Determination of cell type‐specific proteome signatures of primary human leukocytes, endothelial cells, keratinocytes, hepatocytes, fibroblasts and melanocytes by comparative proteome profiling
Authors: Slany Astrid , Paulitschke Verena , Haudek‐Prinz Verena , Meshcheryakova Anastasia , Gerner Christopher
Published: February 2014

Cells gain their functional specialization by different protein synthesis. A lot of knowledge with respect to cell type‐specific proteins has been collected during the last thirty years. This knowledge was built mainly by using antibodies. Nowadays, modern MS, which supports comprehensive proteome analyses of biological samples, may render possible the search for cell type‐specific proteins as well. However, a therefore necessary systematic MS study comprising many different cell types has not been performed until now. Here we present a proteome analysis strategy supporting the automated and meaningful comparison of any biological samples. We have presently applied this strategy to six different primary human cell types, namely leukocytes, endothelial cells, keratinocytes, hepatocytes, fibroblasts, and melanocytes. Comparative analysis of the resulting proteome profiles allowed us to select proteins specifically identified in one of the six cell types and not in any of the five others. Based on these results, we designated cell type‐specific proteome signatures consisting each of six such characteristic proteins. These signatures independently reproduced well‐known marker proteins already established for FACS analyses in addition to novel candidate marker proteins. We applied these signatures for the interpretation of proteome profiles obtained from the analyses of hepatocellular carcinoma‐associated tissue homogenates and normal liver tissue homogenates. The identification of members of the above described signatures gave us an indication of the presence of characteristic cells in the diseased tissues and thus supported the interpretation of the proteomics data of these complex biological samples.
Genetic polymorphisms of 20 short tandem repeat loci from the Han population in Henan, China
Authors: Wang Hong‐Dan , Wu Dong , Feng Zhan‐Qi , Jing Zhi‐An , Li Tao , Guo Qian‐Nan , Zhang Xian‐Ping , Hou Qiao‐Fang , Guo Liang‐Jie , Kang Bing , Zhang Hui , Zhu Bo‐Feng , Liao Shi‐Xiu
Published: February 2014

The aim of this study was to investigate the genetic polymorphism of 20 short tandem repeat (STR) loci including D1S1656, D2S1338, D3S1358, D5S818, D6S1043, D7S820, D8S1179, D12S391, D13S317, D16S539, D18S51, D19S433, D21S11, CSF1PO, FGA, Penta D, Penta E, TH01, TPOX, and vWA in Han population of Henan, China and to assess its value in forensic science. Genomic DNA was extracted from 274 blood samples of unrelated healthy individuals in the Henan Han population. Alleles were amplified with PowerPlex® 21 system kit and PCR products were detected with ABI3130 genetic analyzer (Applied Biosystems) and the data were analyzed with modified PowerStats v1.2. A total of 229 alleles were observed in this Han population and the allelic frequencies ranged from 0.0020 to 0.5090 in the present study. Observed genotype distributions for each locus do not show deviations from Hardy–Weinberg equilibrium expectations (p< 0.05). The combined power of discrimination, combined power of exclusion, and combined matching probability of this 20 STR loci were 0.999999999, 0.999999994603, and 4.0433 × 10−24, respectively. The 20 STR loci are highly polymorphic in the Han population of Henan, China and they may be of great value in forensic science and human population genetics.
Hydrophobic supplements in cell‐free systems: Designing artificial environments for membrane proteins
Authors: Hein Christopher , Henrich Erik , Orbán Erika , Dötsch Volker , Bernhard Frank
Published: February 2014

Membrane proteins (MPs) are of central interest for the pharmaceutical industry but their production is usually a challenging task. The complex folding mechanisms of newly synthesized MPs often require interactions with specific compounds for improved stability. Conditions for the production of high‐quality samples are therefore difficult to predict and frequently cannot be provided in conventional protein expression platforms. Cell‐free (CF) biosynthetic systems allow, in contrast to living cells, nonrestricted access to the protein production machinery. Reaction conditions can be adjusted according to particular requirements and modified by supplementing single additives or even cocktails of compounds. These options have initiated completely new research fields for the cotranslational stabilization and folding of MPs in artificial environments. Based on established and efficient CF production protocols, a recent focus was to explore and define suitable supplements for CF expression reactions that are useful for the generation of high‐quality MP samples. Besides classical detergents and lipids, a variety of new compounds with interesting properties have been discovered and synthesized. We compile the currently available toolbox for MP solubilization in CF systems and summarize new developments and perspectives for the directed modulation of CF biosynthetic environments.
Simulation of scree‐slope dynamics: investigating the distribution of debris avalanche events in an idealized two‐dimensional model
Authors: Bithell Mike , Richards Keith S. , Bithell Erica G.
Published: February 2014

We present a two‐dimensional model of the development of scree slopes using the discrete‐element method. We concentrate on the dynamics of the accumulating debris at the cliff foot rather than on the failure modes of the cliff‐face or shape of the underlying rock surface. The evolution of this unconsolidated material is intermittent and systematically changing over time, with an early high disturbance regime, dominated by a characteristic event size (where 65% of particles in the debris are in motion to some extent), replaced at later times by many shallow slides interspersed with infrequent large events that involve motion through almost the full scree depth. These large slides lead to a stratigraphy in which the layers of material are stretched almost horizontal near the base of the slope. The scree surface thus shows a gradient in age with most recent rock‐fall close to the cliff and the oldest rock‐fall debris outcropping at the foot. The final surface slope tends to show little curvature, and the final mean slope is well correlated with the angle of internal friction of the particles, although the change is very small over a wide range of friction angles [final slope (in degrees relative to horizontal) ~ 0.043 × internal friction angle + 17.49, with a correlation coefficient of 0.89, p‐value 0.0001]. Some weak size‐segregation of the debris is found, but this seems to have little to do with individual particles bounding down the slope. The shape of the rock core agrees largely with the analytic forms given by Fisher–Lehmann and Bakker–Le Heux expressions, but the original simple Fisher quadratic can give the best fit. Overall the evolution shows a remarkable insensitivity to the model parameters, suggesting that the controls on dry scree‐slope evolution are primarily geometric in character. Copyright © 2014 John Wiley & Sons, Ltd.
Co‐channel interference in two‐tier heterogeneous networks: analytical model and ergodic capacity
Authors: Li Yuan , Peng Mugen , Manzoor Ahmed , Wang Chonggang
Published: February 2014

The modelling of co‐channel interference in heterogeneous networks (HetNets) is increasingly highlighted for the spectrum underlay mechanism where the macro base stations (MBSs) and low‐power nodes (LPNs) share the same radio resources. To clarify the characteristics of co‐channel interference, an analytical interference model is developed in this paper for the two‐tier hierarchical HetNets in Long‐Term‐Evolution‐Advanced systems, which consists of MBSs with deterministic locations and LPNs locating with a random Poisson field. The distribution of aggregate interference is analysed, and the parameters impacting the proposed interference model are evaluated. In the proposed aggregate interference model, the success probability is derived on the basis of the moment generation function. Further, the ergodic capacity is developed in high signal‐to‐noise ratio region, and its closed‐form expressions are derived for both MBSs and LPNs. Simulation results are presented to validate the analytical results of proposed interference model. Copyright © 2014 John Wiley & Sons, Ltd.
Prognostic value of changes in resting‐state functional connectivity patterns in cognitive recovery after stroke: A 3T fMRI pilot study
Authors: Dacosta‐Aguayo R. , Graña M. , Savio A. , Fernández‐Andújar M. , Millán M. , López‐Cancio E. , Cáceres C. , Bargalló N. , Garrido C. , Barrios M. , Clemente I. C. , Hernández M. , Munuera J. , Dávalos A. , Auer T. , Mataró M.
Published: February 2014

Resting‐state studies conducted with stroke patients are scarce. First objective was to explore whether patients with good cognitive recovery showed differences in resting‐state functional patterns of brain activity when compared to patients with poor cognitive recovery. Second objective was to determine whether such patterns were correlated with cognitive performance. Third objective was to assess the existence of prognostic factors for cognitive recovery. Eighteen right‐handed stroke patients and eighteen healthy controls were included in the study. Stroke patients were divided into two groups according to their cognitive improvement observed at three months after stroke. Probabilistic independent component analysis was used to identify resting‐state brain activity patterns. The analysis identified six networks: frontal, fronto‐temporal, default mode network, secondary visual, parietal, and basal ganglia. Stroke patients showed significant decrease in brain activity in parietal and basal ganglia networks and a widespread increase in brain activity in the remaining ones when compared with healthy controls. When analyzed separately, patients with poor cognitive recovery (n = 10) showed the same pattern as the whole stroke patient group, while patients with good cognitive recovery (n = 8) showed increased activity only in the default mode network and fronto‐temporal network, and decreased activity in the basal ganglia. We observe negative correlations between basal ganglia network activity and performance in Semantic Fluency test and Part A of the Trail Making Test for patients with poor cognitive recovery. A reverse pattern was observed between frontal network activity and the abovementioned tests for the same group. Hum Brain Mapp 35:3819–3831, 2014. © 2014 The Authors. Human Brain Mapping published by Wiley Periodicals, Inc.
Reactivity of sensorimotor oscillations is altered in children with hemiplegic cerebral palsy: A magnetoencephalographic study
Authors: Pihko Elina , Nevalainen Päivi , Vaalto Selja , Laaksonen Kristina , Mäenpää Helena , Valanne Leena , Lauronen Leena
Published: February 2014

Cerebral palsy (CP) is characterized by difficulty in control of movement and posture due to brain damage during early development. In addition, tactile discrimination deficits are prevalent in CP. To study the function of somatosensory and motor systems in CP, we compared the reactivity of sensorimotor cortical oscillations to median nerve stimulation in 12 hemiplegic CP children vs. 12 typically developing children using magnetoencephalography. We also determined the primary cortical somatosensory and motor representation areas of the affected hand in the CP children using somatosensory‐evoked magnetic fields and navigated transcranial magnetic stimulation, respectively. We hypothesized that the reactivity of the sensorimotor oscillations in alpha (10 Hz) and beta (20 Hz) bands would be altered in CP and that the beta‐band reactivity would depend on the individual pattern of motor representation. Accordingly, in children with CP, suppression and rebound of both oscillations after stimulation of the contralateral hand were smaller in the lesioned than intact hemisphere. Furthermore, in two of the three children with CP having ipsilateral motor representation, the beta‐ but not alpha‐band modulations were absent in both hemispheres after affected hand stimulation suggesting abnormal sensorimotor network interactions in these individuals. The results are consistent with widespread alterations in information processing in the sensorimotor system and complement current understanding of sensorimotor network development after early brain insults. Precise knowledge of the functional sensorimotor network organization may be useful in tailoring individual rehabilitation for people with CP. Hum Brain Mapp 35:4105–4117, 2014. © 2014 Wiley Periodicals, Inc.
Longitudinal growth and morphology of the hippocampus through childhood: Impact of prematurity and implications for memory and learning
Authors: Thompson Deanne K. , Omizzolo Cristina , Adamson Christopher , Lee Katherine J. , Stargatt Robyn , Egan Gary F. , Doyle Lex W. , Inder Terrie E. , Anderson Peter J.
Published: February 2014

The effects of prematurity on hippocampal development through early childhood are largely unknown. The aims of this study were to (1) compare the shape of the very preterm (VPT) hippocampus to that of full‐term (FT) children at 7 years of age, and determine if hippocampal shape is associated with memory and learning impairment in VPT children, (2) compare change in shape and volume of the hippocampi from term‐equivalent to 7 years of age between VPT and FT children, and determine if development of the hippocampi over time predicts memory and learning impairment in VPT children. T1 and T2 magnetic resonance images were acquired at both term equivalent and 7 years of age in 125 VPT and 25 FT children. Hippocampi were manually segmented and shape was characterized by boundary point distribution models at both time‐points. Memory and learning outcomes were measured at 7 years of age. The VPT group demonstrated less hippocampal infolding than the FT group at 7 years. Hippocampal growth between infancy and 7 years was less in the VPT compared with the FT group, but the change in shape was similar between groups. There was little evidence that the measures of hippocampal development were related to memory and learning impairments in the VPT group. This study suggests that the developmental trajectory of the human hippocampus is altered in VPT children, but this does not predict memory and learning impairment. Further research is required to elucidate the mechanisms for memory and learning difficulties in VPT children. Hum Brain Mapp 35:4129–4139, 2014. © 2014 Wiley Periodicals, Inc.
Lactation‐induced reduction in hippocampal neurogenesis is reversed by repeated stress exposure
Authors: Hillerer Katharina M. , Neumann Inga D. , Couillard‐Despres Sebastien , Aigner Ludwig , Slattery David A.
Published: February 2014

The peripartum period is a time of high susceptibility for mood and anxiety disorders, some of which have recently been associated with alterations in hippocampal neurogenesis. Several factors including stress, aging, and, perhaps unexpectedly, lactation have been shown to decrease hippocampal neurogenesis. Intriguingly, lactation is also a time of reduced stress responsivity suggesting that the effect of stress on neurogenic processes may differ during this period. Therefore, the aim of the present study was to assess the effect of repeated stress during lactation [2 h restraint stress from lactation day (LD) 2 to LD13] on brain weight, hippocampal volume, cell proliferation and survival, and on neuronal and astroglial differentiation. In addition to confirming the known lactation‐associated decrease in cell proliferation and survival, we could reveal that stress reversed the lactation‐induced decrease in cell proliferation, while it did not affect survival of newly born cells, nor the number of mature neurons , nor did it alter immature neuron production or the number of astroglial cells in lactation. Stress exposure increased relative brain weight and hippocampal volume mirroring the observed changes in neurogenesis. Interestingly, hippocampal volume and relative brain weight were lower in lactation as compared to nulliparous females under nonstressed conditions. This study assessed the effect of stress during lactation on hippocampal neurogenesis and indicates that stress interferes with important peripartum adaptations at the level of the hippocampus. © 2014 Wiley Periodicals, Inc.
VEGF and VEGFR genotyping in the prediction of clinical outcome for HCC patients receiving sorafenib: The ALICE‐1 study
Authors: Scartozzi Mario , Faloppi Luca , Svegliati Baroni Gianluca , Loretelli Cristian , Piscaglia Fabio , Iavarone Massimo , Toniutto Pierluigi , Fava Giammarco , De Minicis Samuele , Mandolesi Alessandra , Bianconi Maristella , Giampieri Riccardo , Granito Alessandro , Facchetti Floriana , Bitetto Davide , Marinelli Sara , Venerandi Laura , Vavassori Sara , Gemini Stefano , D'Errico Antonietta , Colombo Massimo , Bolondi Luigi , Bearzi Italo , Benedetti Antonio , Cascinu Stefano
Published: February 2014

Although new treatment modalities changed the global approach to hepatocellular carcinoma (HCC), this disease still represents a medical challenge. Currently, the therapeutic stronghold is sorafenib, a tyrosine kinase inhibitor (TKI) directed against the vascular endothelial growth factor (VEGF) family. Previous observations suggested that polymorphisms of VEGF and its receptor (VEGFR) genes may regulate angiogenesis and lymphangiogenesis and thus tumour growth control. The aim of our study was to evaluate the role of VEGF and VEGFR polymorphisms in determining the clinical outcome of HCC patients receiving sorafenib. From a multicentre experience 148 samples (tumour or blood samples) of HCC patients receiving sorafenib were tested for VEGF‐A, VEGF‐C and VEGFR‐1,2,3 single nucleotide polymorphisms (SNPs). Patients' progression‐free survival (PFS) and overall survival (OS) were analysed. At univariate analysis VEGF‐A alleles C of rs25648, T of rs833061, C of rs699947, C of rs2010963, VEGF‐C alleles T of rs4604006, G of rs664393, VEGFR‐2 alleles C of rs2071559, C of rs2305948 were significant predictors of PFS and OS. At multivariate analysis rs2010963, rs4604006 and BCLC (Barcelona Clinic Liver Cancer) stage resulted to be independent factors influencing PFS and OS. Once prospectively validated, the analysis of VEGF and VEGFR SNPs may represent a clinical tool to better identify HCC patients more likely to benefit from sorafenib. On the other hand, the availability of more accurate predictive factors could help avoiding unnecessary toxicities to potentially resistant patients who may be optimal candidates for different treatments interfering with other tumour molecular pathways.