bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vivo imaging of nuclear‐cytoplasmic deformation and partition during cancer cell death due to immune rejection
Authors: Amoh Yasuyuki , Hamada Yuko , Katsuoka Kensei , Hoffman Robert M. 
Published: September 2011

AbstractIn this report, we investigated the in vivo cell biology of cancer cells during immune rejection. The use of nestin‐driven green fluorescent protein (ND‐GFP) transgenic mice as hosts, in which nascent blood vessels express GFP, and implanted dual‐color mouse mammary tumor 060562 (MMT) cells, in which the cytoplasm expresses red fluorescent protein (RFP) and the nuclei express GFP, allowed very important novel observations of angiogenesis and subcellular death pathways during immune rejection of a tumor. Nascent blood vessels did not form in the initially‐growing mouse mammary tumor in ND‐GFP immunocompetent mice. In contrast, in ND‐GFP immunodeficient nude mice, numerous GFP‐expressing nascent blood vessels grew into the tumor. The results suggest that insufficient nascent tumor angiogenesis was important in tumor rejection. During immune rejection, the cancer cells deformed their cytoplasm and nuclei, which were readily imaged by RFP and GFP, respectively. The nuclear membrane of the cancer cells ruptured, and chromatin extruded during partition of cytoplasm and nuclei. T lymphocytes infiltrated into the initially‐growing tumor in the nestin‐GFP transgenic immunocompetent mice. The cytotoxic role of the sensitized T lymphocytes was confirmed in vitro when they were co‐cultured with MMT cells. The CD8a‐positive lymphocytes attached to the cancer cells and caused nuclear condensation, deformation, and partition from their cytoplasm, similar to what occurred in vivo. The color‐coded subcellular fluorescence‐imaging model of immune rejection of cancer cells can provide a comprehensive system for further testing of immune‐based treatment for cancer. J. Cell. Biochem. 113: 465–472, 2012. © 2011 Wiley Periodicals, Inc.
Oct‐3/4 promotes migration and invasion of glioblastoma cells
Authors: Kobayashi Kana , Takahashi Hisaaki , Inoue Akihiro , Harada Hironobu , Toshimori Shinichi , Kobayashi Yukako , Goto Katsuhiro , Sugimoto Kana , Yano Hajime , Ohnishi Takanori , Tanaka Junya 
Published: September 2011

AbstractAs a result of increased glioblastoma migration and invasion into normal brain parenchyma, treatment of local tumor recurrence following initial treatment in glioblastoma patients remains challenging. Recent studies have demonstrated increased Oct‐3/4 expression, a self‐renewal regulator in stem cells, in glioblastomas. However, little is known regarding the influence of Oct‐3/4 in glioblastoma cell invasiveness. The present study established Oct‐3/4‐overexpressing glioblastoma cells, which were prepared from human glioblastoma patients, to assess migration, invasion, and mRNA expression profiles of integrins and matrix metalloproteinases (MMPs). Compared with control cells, Oct‐3/4 expressing‐glioblastoma cells exhibited increased migration and invasion in wound healing and Matrigel invasion assays. Oct‐3/4 overexpression resulted in upregulated FAK and c‐Src expression, which mediate integrin signals. Vinculin accumulated along the leading edges of Oct‐3/4 expressing‐glioblastoma cells and associated with membrane ruffles during cell migration. Oct‐3/4 expressing‐cells exhibited increased MMP‐13 mRNA expression and MMP‐13 knockdown by shRNA suppressed cell invasion into Matrigel and organotypic brain slices. These results suggested that Oct‐3/4 enhanced degradation of surrounding extracellular matrix by increasing MMP‐13 expression and altering integrin signaling. Therefore, Oct‐3/4 might contribute to tumor promoting activity in glioblastomas. J. Cell. Biochem. 113: 508–517, 2012. © 2011 Wiley Periodicals, Inc.
A sequence‐based computational model for the prediction of the solvent accessible surface area for α‐helix and β‐barrel transmembrane residues
Authors: Wang Chengqi , Xi Lili , Li Shuyan , Liu Huanxiang , Yao Xiaojun 
Published: September 2011

AbstractPredicting the solvent accessible surface area (ASA) of transmembrane (TM) residues is of great importance for experimental researchers to elucidate diverse physiological processes. TM residues fall into two major structural classes (α‐helix membrane protein and β‐barrel membrane protein). The reported solvent ASA prediction models were developed for these two types of TM residues respectively. However, this prevents the general use of these methods because one cannot determine which model is suitable for a given TM residue without information of its type. To conquer this limitation, we developed a new computational model that can be used for predicting the ASA of both TM α‐helix and β‐barrel residues. The model was developed from 78 α‐helix membrane protein chains and 24 β‐barrel membrane protein. Its prediction ability was evaluated by cross validation method and its prediction result on an independent test set of 20 membrane protein chains. The results show that our model performs well for both types of TM residues and outperforms other prediction model which was developed for the specific type of TM residues. The prediction results also proved that the random forest model incorporating conservation score is an effective sequence‐based computational approach for predicting the solvent ASA of TM residues. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Initiation of BMP2 signaling in domains on the plasma membrane
Authors: Bonor Jeremy , Adams Elizabeth L. , Bragdon Beth , Moseychuk Oleksandra , Czymmek Kirk J. , Nohe Anja 
Published: September 2011

AbstractBone morphogenetic protein 2 (BMP2) is a potent growth factor crucial for cell fate determination. It directs the differentiation of mesenchymal stem cells into osteoblasts, chondrocytes, adipocytes, and myocytes. Initiation of BMP2 signaling pathways occurs at the cell surface through type I and type II serine/threonine kinases housed in specific membrane domains such as caveolae enriched in the caveolin‐1 beta isoform (CAV1β, caveolae) and clathrin‐coated pits (CCPs). In order for BMP2 to initiate Smad signaling it must bind to its receptors on the plasma membrane resulting in the phosphorylation of the BMP type Ia receptor (BMPRIa) followed by activation of Smad signaling. The current model suggests that the canonical BMP signaling pathway, Smad, occurs in CCPs. However, several recent studies suggested Smad signaling may occur outside of CCPs. Here, we determined; (i) The location of BMP2 binding to receptors localized in caveolae, CCPs, or outside of these domains using AFM and confocal microscopy. (ii) The location of phosphorylation of BMPRIa on the plasma membrane using membrane fractionation, and (iii) the effect of down regulation of caveolae on Smad signaling. Our data indicate that BMP2 binds with highest force to BMP receptors (BMPRs) localized in caveolae. BMPRIa is phosphorylated in caveolae and the disruption of caveolae‐inhibited Smad signaling in the presence of BMP2. This suggests caveolae are necessary for the initiation of Smad signaling. We propose an extension of the current model of BMP2 signaling, in which the initiation of Smad signaling is mediated by BMPRs in caveolae. J. Cell. Physiol. 227: 2880–2888, 2012. © 2011 Wiley Periodicals, Inc.
Engineered endothelial progenitor cells that overexpress prostacyclin protect vascular cells
Authors: Liu Qi , Xi Yutao , Terry Toya , So Shui‐Ping , Mohite Anita , Zhang Jia , Wu Geru , Liu Xiaobing , Cheng Jie , Ruan Ke‐He , Willerson James T. , Dixon Richard A.F. 
Published: September 2011

AbstractProstacyclin (PGI2) is a potent vasodilator and important mediator of vascular homeostasis; however, its clinical use is limited because of its short (<2‐min) half‐life. Thus, we hypothesize that the use of engineered endothelial progenitor cells (EPCs) that constitutively secrete high levels of PGI2 may overcome this limitation of PGI2 therapy. A cDNA encoding COX‐1‐10aa‐PGIS, which links human cyclooxygenase‐1 (COX‐1) to prostacyclin synthase (PGIS), was delivered via nucleofection into outgrowth EPCs derived from rat bone marrow mononuclear cells. PGI2‐secreting strains (PGI2‐EPCs) were established by continuous subculturing of transfected cells under G418 selection. Genomic PCR, RT‐PCR, and Western blot analyses confirmed the overexpression of COX‐1‐10aa‐PGIS in PGI2‐EPCs. PGI2‐EPCs secreted significantly higher levels of PGI2 in vitro than native EPCs (P < 0.05) and showed higher intrinsic angiogenic capability; conditioned medium (CM) from PGI2‐EPCs promoted better tube formation than CM from native EPCs (P < 0.05). Cell‐ and paracrine‐mediated in vitro angiogenesis was attenuated when COX‐1‐10aa‐PGIS protein expression was knocked down. Whole‐cell patch‐clamp studies showed that 4‐aminopyridine‐sensitive K+ current density was increased significantly in rat smooth muscle cells (rSMCs) cocultured under hypoxia with PGI2‐EPCs (7.50 ± 1.59 pA/pF; P < 0.05) compared with rSMCs cocultured with native EPCs (3.99 ± 1.26 pA/pF). In conclusion, we successfully created EPC strains that overexpress an active novel enzyme resulting in consistent secretion of PGI2. PGI2‐EPCs showed enhanced intrinsic proangiogenic properties and provided favorable paracrine‐mediated cellular protections, including promoting in vitro angiogenesis of native EPCs and hyperpolarization of SMCs under hypoxia. J. Cell. Physiol. 227: 2907–2916, 2012. © 2011 Wiley Periodicals, Inc.
Transplacental fetal therapy for junctional ectopic tachycardia
Authors: Ishikawa Kaori , Kikuchi Akihiko , Matsui Hikoro , Tamaru Shunsuke , Imada Shinya , Horikoshi Tsuguhiro , Takagi Kimiyo 
Published: September 2011

AbstractJunctional ectopic tachycardia (JET) is a rare type of tachyarrhythmia. A 39‐year‐old woman was transferred to our hospital for fetal tachyarrhythmia at 32 weeks' gestation. Fetal cardiac sonography revealed atrial and ventricular rates of 120–130 and 175–230 bpm, respectively, without 1:1 atrioventricular relationship. As ventricular tachycardia was considered to be the most probable diagnosis, transplacental therapy with digoxin and sotalol was done with partial response. Diagnosis of JET was made after birth. Although fetal JET is rare and prenatal diagnosis and treatment of this condition is still a challenge, differential diagnosis of fetal tachyarrhythmia should include this disorder. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound 40:119–123, 2012
Selectivity of some basic solutes on a poly(methyltetradecylsiloxane)‐silica stationary phase
Authors: Borges Endler M. , Collins Carol H. 
Published: September 2011

AbstractComplex analyses of polar compounds, especially basic ones, require more selective stationary phases. The present paper describes a stationary phase prepared by thermal immobilization of poly(methyltetradecylsiloxane) onto chromatographic silica (PMTDS‐SiO2). This stationary phase presents hydrophobic and ion‐exchange interactions that confer both high retention and unique selectivities for basic solutes. The influence of ion‐exchange interactions is confirmed by the increase in retention factors of basic solutes when the mobile‐phase pH changes from acidic to neutral and by the decrease in retention factors when the mobile‐phase pH changes from neutral to alkaline. The ion‐exchange properties of the stationary phase are enriched in neutral mobile phase (pH 7–7.5) using soft Lewis bases such as tricine and tris as buffers but are suppressed in both acidic (pH 2.5–6) and highly alkaline mobile phases (pH≤10). Increasing both temperature and flow rate permits more rapid separations while maintaining the selectivity. The stability of the stationary phase is evaluated with acid, neutral and alkaline mobile phases.
Practical comparison of LC columns packed with different superficially porous particles for the separation of small molecules and medium size natural products
Authors: Yang Peilin , McCabe Terry , Pursch Matthias 
Published: September 2011

AbstractCommercial C18 columns packed with superficially porous particles of different sizes and shell thicknesses (Ascentis Express, Kinetex, and Poroshell 120) or sub‐2‐μm totally porous particles (Acquity BEH) were systematically compared using a small molecule mixture and a complex natural product mixture as text probes. Significant efficiency loss was observed on 2.1‐mm id columns even with a low dispersion ultra‐high pressure liquid chromatography system. The Kinetex 4.6‐mm id column packed with 2.6‐μm particles exhibited the best overall efficiency for small molecule separations and the Poroshell 120 column showed better performance for mid‐size natural product analytes. The Kinetex 2.1‐mm id column packed with 1.7‐μm particles did not deliver the expected performance and the possible reasons besides extra column effect have been proved to be frictional heating effect and poor column packing quality. Different column retentivities and selectivities have been observed on the four C18 columns of different brands for the natural product separation. Column batch‐to‐batch variability that has been previously observed on the Ascentis Express column was also observed on the Kinetex and Poroshell 120 column.
Resveratrol derivative‐rich melinjo (Gnetum gnemon L.) seed extract suppresses multiple angiogenesis‐related endothelial cell functions and tumor angiogenesis
Authors: Kunimasa Kazuhiro , Ohta Toshiro , Tani Hiroko , Kato Eishin , Eguchi Ryoji , Kaji Kazuhiko , Ikeda Katsumi , Mori Hideki , Mori Mari , Tatefuji Tomoki , Yamori Yukio 
Published: September 2011

AbstractAngiogenesis is a promising target for cancer prevention and treatment. This study aimed to determine the antiangiogenic effects of melinjo (Gnetum gnemon L.) seed extract and its resveratrol derivative components, such as gnetin C (GC), gnetin L (GL), gnemonoside A (GMA), gnemonoside C (GMC), and gnemonoside D (GMD). An ethanol extract of melinjo seeds (EEMS) and the two gnetins markedly inhibited the proliferation and tube formation of human umbilical vein endothelial cells (HUVEC) stimulated with vascular endothelial growth factor and basic fibroblast growth factor. The inhibitory effects of GC and GL were much stronger than those of resveratrol. GMC and GMD inhibited only proliferation, whereas GMA had almost no effect on the two endothelial cell functions. The EEMS and GC also reduced the cell viability of tube‐forming HUVEC, with accompanying ERK1/2 inactivation, and suppressed the migration of HUVEC. Furthermore, dietary intake of EEMS significantly inhibited tumor angiogenesis in a mouse dorsal air sac assay. In conclusion, we found that the EEMS and its resveratrol derivatives, particularly GC, suppress multiple angiogenesis‐related endothelial cell functions and/or tumor angiogenesis, indicating that the melinjo seeds and the natural resveratrol derivatives may be useful for cancer prevention and treatment.
Analysis of industrial c‐Si solar cell's front metallization by advanced numerical simulation
Authors: Yang Yang , Altermatt Pietro P. , Zhu Weihua , Liang Xueqin , Shen Hui 
Published: September 2011

ABSTRACTThe influence of the front metallization on the performance of industrially fabricated c‐Si solar cells is quantified by means of a combination of optical, semiconductor, and circuit modeling. Special attention is given to the front metallization of conventionally processed emitters. First, we verify our model by reproducing the measured I–V curves of industrially fabricated cells. Based on this, the potential changes in performance are predicted by variations in finger spacing, finger resistivity, busbar numbers, and contact resistivity. We also assess the benefits derived from the higher aspect ratios of the fingers: if the fingers are 120 (or 60 µm) wide, increasing the finger height from 15 to 25 µm increases their efficiency by 0.06% (or 0.7%) absolute if a conventional emitter is used. This implies that, if the fingers cannot be made as narrow as 60 µm in industrial mass production, the economic gains from higher aspect ratios may be rather limited, because there is a trade‐off between improved cell efficiency and the increasing cost of silver. Simulations show that, for the light‐induced plating approach, the seed layer must be made as narrow as 50 µm in order to achieve an efficiency gain of 1% absolute with a plating of 10 µm silver. Copyright © 2011 John Wiley & Sons, Ltd.
On the purification of CVD grown boron doped single‐walled carbon nanotubes
Authors: Ruiz‐Soria G. , Ayala P. , Puchegger S. , Kataura H. , Yanagi K. , Pichler T. 
Published: September 2011

AbstractIn this paper, we report a facile purification method of boron‐doped single‐walled carbon nanotubes (SWCNTs) produced by high vacuum chemical vapor deposition (HV‐CVD). The raw material was doped in situ during growth, with a B content below 0.5 at.%, estimated by means of X‐ray photoelectron spectroscopy (XPS). Using ultracentrifugation combined with a mild acid solution pH neutralization, we have proved it is feasible to purify this material, which originally contains synthesis byproducts that differ from the typical catalytic remaining in pristine carbon nanotube samples produced with a similar method. The diameter size and distribution – previous and after purification – have been monitored by multi‐frequency Raman spectroscopy.
USE OF HYDRAULIC MODELLING TO ASSESS PASSAGE FLOW CONNECTIVITY FOR SALMON IN STREAMS
Authors: Grantham T. E. 
Published: September 2011

ABSTRACTThe maintenance of hydrologic connectivity in river networks has become an important principle for guiding management and conservation planning for threatened salmon populations, yet our understanding of how fish movement is impaired by spatial and temporal variation in connectivity remains limited. In this study, a two‐dimensional hydraulic modelling approach is presented to evaluate flow connectivity in relation to passage requirements of adult steelhead trout (Oncorhynchus mykiss) in coastal California streams. High‐resolution topographic data of stream reaches with distinct channel morphology were collected using terrestrial light detection and ranging surveys and linked with water surface measurements to calibrate hydraulic model simulations. Quantitative metrics of longitudinal flow connectivity were developed to assess fish passage suitability in relation to stream discharge. Measured flow data from the 2008–2009 winter season and simulated long‐term records indicated that suitable passage flows occur with relatively low frequency and duration at all sites, suggesting that instream flow protections for fish passage are warranted. Results from the hydraulic modelling simulations were then compared with two alternative methods for assessing passage flows. A regional formula used by the State of California to identify minimum instream flow needs provided conservative estimates of passage flow requirements, whereas an approach based on riffle crest water depths underestimated flow needs. The hydraulic modelling approach appears well suited for simulating flows for fish passage studies and may be particularly useful for testing alternative environmental flow assessment methods and evaluating habitat–flow relationships in stream reaches of importance, such as critical habitat for threatened fish species. Copyright © 2011 John Wiley & Sons, Ltd.
Secured hierarchical secret sharing using ECC based signcryption
Authors: Basu Atanu , Sengupta Indranil , Sing Jamuna Kanta 
Published: September 2011

ABSTRACTMost of the existing hierarchical secret‐sharing schemes are unconditionally (non‐cryptographically) secured, and they cannot survive from various types of attacks especially when the participants use resource‐constrained wireless mobile devices. In our proposed secured hierarchical secret‐sharing scheme, the participants are partitioned into different levels according to their ranks in any organization. In this hierarchy‐based secret‐sharing scheme, the trusted dealer distributes the delegated secret keys as shares to the participants through our proposed signcryption scheme that reduces computational cost and communication overhead. Again, the participants submit the signcrypted shares to the trusted dealer for reconstruction of the secret key. The proposed scheme distinguishes each level of hierarchy qualitatively, and any type of active or passive adversary or colluding participants cannot reconstruct the secret key. The novelty of our scheme is that it is conditionally (cryptographically) as well as unconditionally secured, and the participants may use resource‐constrained wireless mobile devices. The access structure chosen for our scheme increases the resilience of our scheme. Our proposed scheme is perfect and ideal. Copyright © 2011 John Wiley & Sons, Ltd.
VeriEST: verification via primary user emulation signal‐based test for secure distributed spectrum sensing in cognitive radio networks
Authors: Kim Mihui , Chung Min Young , Choo Hyunseung 
Published: September 2011

ABSTRACTSecure distributed spectrum sensing (DSS) schemes in cognitive radio networks (CRNs) have been proposed to reliably detect the signals of the primary users (PUs) even when compromised nodes generate forged sensing reports. However, they have limited sensing accuracy for PU signals because of the absence of exact signal patterns of PUs. This is caused by Federal Communications Commission restriction on (no modification of) PUs, and thus, the CRNs cannot communicate with the PUs to obtain such patterns. We propose a verification framework utilizing primary user emulation signals that can be applied to existing DSS schemes to address this challenge. This will reinforce the robustness against forged sensing values. We then develop a concrete verification scheme based on this framework and an existing secure DSS scheme. We evaluate our approach via in‐depth simulation and analysis compared with the existing scheme. Results show that our approach improves sensing accuracy and fusion speed in the cases of attack. Copyright © 2011 John Wiley & Sons, Ltd.
α‐Amylase immobilization on functionalized nano CaCO3 by covalent attachment
Authors: Demir Serap , Gök Sevda Burcu , Kahraman Memet Vezir 
Published: September 2011

AbstractIn this study, α‐amylase was immobilized on glutaraldehyde activated silanized calcium carbonate nanoparticles by a using covalent binding method. The surface modified nano calcium carbonate (CaCO3) were characterized using FTIR and SEM. Immobilization yield was found as 199.43 mg/g of calcium carbonate nanoparticles. The maximum activity was observed at pH 6.5. The immobilized enzyme had a higher activity at elevated temperature (50–90°C) than the free one. Reuse studies demonstrated that the immobilized enzyme could reuse 25 times while retaining 18.2% of its activity. Free enzyme lost its activity completely within 15 days. Vmax values for the free and immobilized enzymes were calculated as 10 and 0.35 mg/mL/min, respectively.
Characterisation of normal corn starch using asymmetrical flow field‐flow fractionation
Authors: Juna Shazia , Huber Anton 
Published: September 2011

AbstractThe apparent average molar masses (Mw,app), apparent average radii of gyration (Rg,app), diffusion co‐efficients (DT), and hydrodynamic radii (Rh) of normal corn (maize) starch and fractions were determined using asymmetrical flow field‐flow fractionation coupled with multi‐angle light scattering and refractive index detectors (AF4/MALS/RI). AM‐type (Fraction A) and AP‐type (Fraction B) were chemically separated from normal corn starch. Normal corn starch and Fractions (A–B) were dissolved in 1 M KSCN using a high pressure microwave vessel. The effect of varying cross flow rates at a fixed channel flow rate upon the Mw,app and Rg,app distributions of normal corn starch and Fractions (A–B) were investigated. The average Mw,app of normal corn starch, Fractions (A) and Fraction (B) were 41 × 106, 1.4 × 106 and 39 × 106 g/mol, respectively, with Rg,app values of 129, 60 and 129 nm, respectively.