bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antiangiogenic agents and late anastomotic complications
Authors: Deshaies Isabelle , Malka David , Soria Jean‐Charles , Massard Christophe , Bahleda Rastio , Elias Dominique 
Published: December 2009

AbstractAnticancer agents targeting circulating vascular endothelial growth factor (VEGF) (e.g., bevacizumab and aflibercept) are strong angiogenesis inhibitors. As such, they may hamper the healing process, notably in the early postoperative period. Whether antiangiogenic agents may be associated with late postoperative healing complications is less known. We reviewed three cases of patients with anastomotic complications under antiangiogenic treatment occurring more than 1 year after initial surgery and we conducted a review of the literature. We report the first case of delayed anastomotic leakage which occurred under aflibercept therapy 13 months after a bilioenteric anastomosis and two cases of delayed rectal anastomotic complications associated with bevacizumab treatment 18 and 78 months after surgery. Fifteen similar cases of late gastrointestinal anastomotic complications were found in the English literature. Antiangiogenic agents are probably not deleterious to a healed wound. However, they appear to be associated with an increased risk of complications in a subgroup of patients. According to the 18 cases reported, the main risk factors appear to be low anterior resection for rectal cancer, perioperative radiotherapy, and early postoperative leak which heals through the formation of abundant and hypervascularized granulation tissue. J. Surg. Oncol. 2010;101:180–183. © 2009 Wiley‐Liss, Inc.
Does intrahepatic cholangiocarcinoma have better prognosis compared to perihilar cholangiocarcinoma?
Authors: Guglielmi Alfredo , Ruzzenente Andrea , Campagnaro Tommaso , Pachera Silvia , Valdegamberi Alessandro , Capelli Paola , Pedica Federica , Nicoli Paola , Conci Simone , Iacono Calogero 
Published: December 2009

AbstractBackground and ObjectivesCholangiocarcinoma can be classified as intrahepatic (ICC) or perihilar (PCC). The objectives of this study is to evaluate the surgical outcomes of patients with PCC and ICC, identify the main prognostic factors related to survival and compare the outcome and the prognostic factors of PCC and ICC.MethodsNinety‐five out of 152 patients observed between January 1990 and December 2007 at Surgical Division of University of Verona Medical School underwent the resection of ICC (33 patients) or PCC (62 patients).ResultsOverall median survival was 24 months with a 3‐ and 5‐year survival rate of 45% and 23%, respectively. Prognostic factors for survival were macroscopic types of the tumor, the resection of extrahepatic bile duct, radical resection, lymph node metastases, and macro‐vascular invasion. Survival was related with the macroscopic type of the tumors with a 5‐year survival rate of 26% and 13% for ICC and PCC, respectively. Univariate analysis identified that negative clinico‐pathological factors where significant more frequently found in PCC compared to ICC.ConclusionWe identified that ICC have longer survival rate compared to PCC. PCC showed a higher frequency of negative clinico‐pathological factors such as non‐radical (R+) resection, perineural infiltration and macro‐vascular invasion. J. Surg. Oncol. 2010;101:111–115. © 2009 Wiley‐Liss, Inc.
ZnO‐Based UV Nanocomposites for Wood Coatings in Outdoor Applications
Authors: Weichelt Franziska , Emmler Rico , Flyunt Roman , Beyer Evelin , Buchmeiser Michael R. , Beyer Mario 
Published: December 2009

AbstractNanocomposite UV coatings with adjustable properties for use on wood substrates in outdoor conditions were developed. Nanoscale ZnO was shown to be an efficient light absorber. Coatings were characterized in terms of elongation at brake, residual PI and double bond conversion, universal hardness, transparency, hydrophobicity, and yellowing. Coated samples were artificially weathered and studied with regard to their optical and mechanical properties, as well as to changes in brightness, transparency, hydrophobicity, and water permeability. The prepared wood coatings showed an increased weather fastness and improved optical properties. The suitability for use in outdoor conditions was assured by optimizing the elasticity of the coating and decreasing its water permeability.magnified image
Absorption Properties of Microgel‐PVP Composite Nanofibers Made by Electrospinning
Authors: Díaz Juan Esteban , Barrero Antonio , Márquez Manuel , Fernández‐Nieves Alberto , Loscertales Ignacio G. 
Published: December 2009

AbstractThe absorption and desorption of water, as well as the retention of certain molecules within a polymeric network, have special interest in a wide range of applications, including drug delivery, biosensing, chemical separation, catalysis, and optics. In this communication, we report the encapsulation by electrospinning of poly(N‐isopropylacrylamide)‐based monodisperse microgels within microfibers of crosslinked poly(vinylpyrrolidone), which is a hydrogel itself, up to concentrations of 40 wt.‐% of the microgels. We present an optical characterization of these composite microfibers and quantify their absorbance, which can be as large as 17 times their de‐swollen weight. Interestingly, this absorbance can be tuned by controlling the values of the temperature and the pH of the medium.magnified image
Polymer Vesicles with a Red Cell‐like Surface Charge: Microvascular Imaging and in vivo Tracking with Near‐Infrared Fluorescence
Authors: Christian David A. , Garbuzenko Olga B. , Minko Tamara , Discher Dennis E. 
Published: December 2009

AbstractPolymersomes are block copolymer‐based vesicles whose long circulation times or “stealth” in vivo coupled with the loading and controlled release of drugs, siRNA, and other compounds has made them attractive for delivery. A brushy corona of non‐ionic polyethylene glycol (PEG) likely contributes stealth, but red blood cells (RBCs) possess a negatively charged glycocalyx and circulate much longer. Polyanionic block copolymers were therefore mixed into polymersomes which were also labeled with a near IR fluorophore to quantify biodistribution in live mice and excised organs. Charge shifts tissue distribution, and high resolution imaging of vesicles in blood capillaries further shows that organ cultures can provide deeper insight into microscale transport within tissue microenvironments.magnified image
Compartmentalization of Gold Nanocrystals in Polymer Microparticles using Electrohydrodynamic Co‐Jetting
Authors: Lim Dong Woo , Hwang Sangyeul , Uzun Oktay , Stellacci Francesco , Lahann Joerg 
Published: December 2009

AbstractPolymer particles with micro‐ and nanoscale anisotropy have received increasing interest for their ability to simultaneously present different physical‐ and chemical properties. In this communication, we demonstrate that gold nanocrystals (NCs) can be selectively incorporated into one compartment of anisotropic polymer particles. Stable bicompartmental particles were prepared via electrohydrodynamic co‐jetting of aqueous nanoparticle suspensions followed by thermal cross‐linking. Bicompartmental particle populations with different NC densities were obtained by varying the NC concentration in the jetting suspension. While NC‐loaded polymer particles showed different optical properties depending on the NC density, they still maintained discrete interfaces between two compartments. Moreover, the fraction of the bicompartmental particles was higher than 98% based on flow cytometry. This study delineates a new approach for preparation of inorganic/organic composite particles with precisely engineered, anisotropic nanoparticle distributions and may contribute to further developments in emerging scientific areas, such as smart materials or particle‐based diagnostics.magnified image
Reduced Graphene Oxide/Poly(3‐hexylthiophene) Supramolecular Composites
Authors: Chunder Anindarupa , Liu Jianhua , Zhai Lei 
Published: December 2009

AbstractPoly(3‐hexylthiophene) (P3HT) supramolecular structures are fabricated on P3HT‐dispersed reduced graphene oxide (RGO) monolayers and surfactant‐free RGO monolayers. P3HT is able to disperse RGO in hot anisole/N,N‐dimethylformamide solvents, and forms nanowires on RGO surfaces through a RGO induced crystallization process. The TEM and AFM investigation of the resultant P3HT/RGO composites shows that P3HT nanowires grow from RGO, and connect individual RGO monolayers. Raman spectroscopy confirms the interaction between P3HT and RGO, which allows the manipulation of the RGO electrical properties. Such a bottom‐up approach provides interesting graphene‐based composites for nanometer‐scale electronics.magnified image
Liquid Crystalline Period Variations in Self‐Assembled Block Copolypeptides–Surfactant Ionic Complexes
Authors: Li Chaoxu , Li Jingguo , Zhang Xiuqiang , Zhang Afang , Mezzenga Raffaele 
Published: December 2009

AbstractWe investigate the complexation of ampholytic poly(N‐isopropylacylamide)‐block‐poly‐ (L‐glutamic acid)‐block‐poly(L‐lysine) (PNiPAM‐b‐PLG‐b‐PLLys) triblock copolymers and PNiPAM‐block‐(PLG‐co‐PLLys) diblock copolymers with counter charged anionic and cationic surfactants. Both triblock and diblock copolymers are able to selectively form complexes through either L‐glutamic acid–cationic surfactant or L‐lysine–anionic surfactant ionic pairs, depending on the protonated or deprotonated states of the ampholytic peptide units. The complexes show ordering at multiple length scales: i) the block copolymer length scale (101 nm), ii) the liquid crystalline length scale (100 nm), and, iii) the peptidic secondary structures length scale (100 nm). We show that the liquid crystalline period can be tuned by varying the random/block copolypeptide architectures and the composition of the ampholytic amino acid species.magnified image
Bis(germyl)ketones: Toward a New Class of Type I Photoinitiating Systems Sensitive Above 500 nm?
Authors: Tehfe Mahamad‐Ali , Blanchard Nicolas , Fries Cedric , Lalevée Jacques , Allonas Xavier , Fouassier Jean Pierre 
Published: December 2009

AbstractThe ability of a bis(germyl)ketone Ph3GeCOGePh3 to act as a photoinitiator of free radical polymerization under visible light is investigated. The results suggest that this compound could be the starting point of a new high performance class of photoinitiators. The excited state processes, as well as the generation and the reactivity of the germyl radicals, are studied by laser flash photolysis, ESR spin trapping experiments, and molecular orbital calculations; they are compared to the results obtained on a mono‐ (germyl)ketone CH3COGePh3. Time dependent density functional theory calculations allow discussion of the strongly red‐shifted ground state absorption of Ph3GeCOGePh3.magnified image
Inhibition of tyrosine phosphorylation of sperm flagellar proteins, outer dense fiber protein‐2 and tektin‐2, is associated with impaired motility during capacitation of hamster spermatozoa
Authors: Mariappa Daniel , Aladakatti Ravindranath H. , Dasari Santosh K. , Sreekumar Arun , Wolkowicz Michael , van der Hoorn Frans , Seshagiri Polani B. 
Published: December 2009

AbstractIn mammals, acquisition of fertilization competence of spermatozoa is dependent on the phenomenon of sperm capacitation. One of the critical molecular events of sperm capacitation is protein tyrosine phosphorylation. In a previous study, we demonstrated that a specific epidermal growth factor receptor (EGFR)‐tyrosine kinase inhibitor, tyrphostin‐A47, inhibited hamster sperm capacitation, accompanied by a reduced sperm protein tyrosine phosphorylation. Interestingly, a high percentage of tyrphostin‐A47‐treated spermatozoa exhibited circular motility, which was associated with a distinct hypo‐tyrosine phosphorylation of flagellar proteins, predominantly of Mr 45,000–60,000. In this study, we provide evidence on the localization of capacitation‐associated tyrosine‐phosphorylated proteins to the nonmembranous, structural components of the sperm flagellum. Consistent with this, we show their ultrastructural localization in the outer dense fiber, axoneme, and fibrous sheath of spermatozoa. Among hypo‐tyrosine phosphorylated major proteins of tyrphostin‐A47‐treated spermatozoa, we identified the 45 kDa protein as outer dense fiber protein‐2 and the 51 kDa protein as tektin‐2, components of the sperm outer dense fiber and axoneme, respectively. This study shows functional association of hypo‐tyrosine‐phosphorylation status of outer dense fiber protein‐2 and tektin‐2 with impaired flagellar bending of spermatozoa, following inhibition of EGFR‐tyrosine kinase, thereby showing the critical importance of flagellar protein tyrosine phosphorylation during capacitation and hyperactivation of hamster spermatozoa. Mol. Reprod. Dev. 77: 182–193, 2010. © 2009 Wiley‐Liss, Inc.
Temporal and noninvasive monitoring of inflammatory‐cell infiltration to myocardial infarction sites using micrometer‐sized iron oxide particles
Authors: Yang Yidong , Yang Yuhui , Yanasak Nathan , Schumacher Autumn , Hu Tom C.‐C. 
Published: December 2009

AbstractMicrometer‐sized iron oxide particles (MPIO) are a more sensitive MRI contrast agent for tracking cell migration compared to ultrasmall iron oxide particles. This study investigated the temporal relationship between inflammation and tissue remodeling due to myocardial infarction (MI) using MPIO‐enhanced MRI. C57Bl/6 mice received an intravenous MPIO injection for cell labeling, followed by a surgically induced MI seven days later (n = 7). For controls, two groups underwent either sham‐operated surgery without inducing an MI post‐MPIO injection (n = 7) or MI surgery without MPIO injection (n = 6). The MRIs performed post‐MI showed significant signal attenuation around the MI site for the mice that received an intravenous MPIO injection for cell labeling, followed by a surgically induced MI seven days later, compared to the two control groups (P < 0.01). The findings suggested that the prelabeled inflammatory cells mobilized and infiltrated into the MI site. Furthermore, the linear regression of contrast‐to‐noise ratio at the MI site and left ventricular ejection function suggested a positive correlation between the labeled inflammatory cell infiltration and cardiac function attenuation during post‐MI remodeling (r2 = 0.98). In conclusion, this study demonstrated an MRI technique for noninvasively and temporally monitoring inflammatory cell migration into the myocardium while potentially providing additional insight concerning the pathologic progression of a myocardial infarction. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
Quantification of punctate iron sources using magnetic resonance phase
Authors: McAuley Grant , Schrag Matthew , Sipos Pál , Sun Shu‐Wei , Obenaus Andre , Neelavalli Jaladhar , Haacke E. Mark , Holshouser Barbara , Madácsi Ramóna , Kirsch Wolff 
Published: December 2009

AbstractIron‐mediated tissue damage is present in cerebrovascular and neurodegenerative diseases and neurotrauma. Brain microbleeds are often present in these maladies and are assuming increasing clinical importance. Because brain microbleeds present a source of pathologic iron to the brain, the noninvasive quantification of this iron pool is potentially valuable. Past efforts to quantify brain iron have focused on content estimation within distributed brain regions. In addition, conventional approaches using “magnitude” images have met significant limitations. In this study, a technique is presented to quantify the iron content of punctate samples using phase images. Samples are modeled as magnetic dipoles and phase shifts due to local dipole field perturbations are mathematically related to sample iron content and radius using easily recognized geometric features in phase images. Phantoms containing samples of a chitosan‐ferric oxyhydroxide composite (which serves as a mimic for hemosiderin) were scanned with a susceptibility‐weighted imaging sequence at 11.7 T. Plots relating sample iron content and radius to phase image features were compared to theoretical predictions. The primary result is the validation of the technique by the excellent agreement between theory and the iron content plot. This research is a potential first step toward quantification of punctate brain iron sources such as brain microbleeds. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
Quantitative susceptibility map reconstruction from MR phase data using bayesian regularization: Validation and application to brain imaging
Authors: de Rochefort Ludovic , Liu Tian , Kressler Bryan , Liu Jing , Spincemaille Pascal , Lebon Vincent , Wu Jianlin , Wang Yi 
Published: December 2009

AbstractThe diagnosis of many neurologic diseases benefits from the ability to quantitatively assess iron in the brain. Paramagnetic iron modifies the magnetic susceptibility causing magnetic field inhomogeneity in MRI. The local field can be mapped using the MR signal phase, which is discarded in a typical image reconstruction. The calculation of the susceptibility from the measured magnetic field is an ill‐posed inverse problem. In this work, a bayesian regularization approach that adds spatial priors from the MR magnitude image is formulated for susceptibility imaging. Priors include background regions of known zero susceptibility and edge information from the magnitude image. Simulation and phantom validation experiments demonstrated accurate susceptibility maps free of artifacts. The ability to characterize iron content in brain hemorrhage was demonstrated on patients with cavernous hemangioma. Additionally, multiple structures within the brain can be clearly visualized and characterized. The technique introduces a new quantitative contrast in MRI that is directly linked to iron in the brain. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
Multivariate statistical mapping of spectroscopic imaging data
Authors: Young Karl , Govind Varan , Sharma Khema , Studholme Colin , Maudsley Andrew A. , Schuff Norbert 
Published: December 2009

AbstractFor magnetic resonance spectroscopic imaging studies of the brain, it is important to measure the distribution of metabolites in a regionally unbiased way; that is, without restrictions to a priori defined regions of interest. Since magnetic resonance spectroscopic imaging provides measures of multiple metabolites simultaneously at each voxel, there is furthermore great interest in utilizing the multidimensional nature of magnetic resonance spectroscopic imaging for gains in statistical power. Voxelwise multivariate statistical mapping is expected to address both of these issues, but it has not been previously employed for spectroscopic imaging (SI) studies of brain. The aims of this study were to (1) develop and validate multivariate voxel‐based statistical mapping for magnetic resonance spectroscopic imaging and (2) demonstrate that multivariate tests can be more powerful than univariate tests in identifying patterns of altered brain metabolism. Specifically, we compared multivariate to univariate tests in identifying known regional patterns in simulated data and regional patterns of metabolite alterations due to amyotrophic lateral sclerosis, a devastating brain disease of the motor neurons. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
In vivo generalized diffusion tensor imaging (GDTI) using higher‐order tensors (HOT)
Authors: Liu Chunlei , Mang Sarah C. , Moseley Michael E. 
Published: December 2009

AbstractGeneralized diffusion tensor imaging (GDTI) using higher‐order tensor (HOT) statistics generalizes the technique of diffusion tensor imaging by including the effect of nongaussian diffusion on the signal of MRI. In GDTI‐HOT, the effect of nongaussian diffusion is characterized by higher‐order tensor statistics (i.e., the cumulant tensors or the moment tensors), such as the covariance matrix (the second‐order cumulant tensor), the skewness tensor (the third‐order cumulant tensor), and the kurtosis tensor (the fourth‐order cumulant tensor). Previously, Monte Carlo simulations have been applied to verify the validity of this technique in reconstructing complicated fiber structures. However, no in vivo implementation of GDTI‐HOT has been reported. The primary goal of this study is to establish GDTI‐HOT as a feasible in vivo technique for imaging nongaussian diffusion. We show that probability distribution function of the molecular diffusion process can be measured in vivo with GDTI‐HOT and be visualized with three‐dimensional glyphs. By comparing GDTI‐HOT to fiber structures that are revealed by the highest resolution diffusion‐weighted imaging (DWI) possible in vivo, we show that the GDTI‐HOT can accurately predict multiple fiber orientations within one white matter voxel. Furthermore, through bootstrap analysis we demonstrate that in vivo measurement of HOT elements is reproducible, with a small statistical variation that is similar to that of diffusion tensor imaging. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.
On the optimum support size in meshfree methods: A variational adaptivity approach with maximum‐entropy approximants
Authors: Rosolen Adrian , Millán Daniel , Arroyo Marino 
Published: December 2009

AbstractWe present a method for the automatic adaption of the support size of meshfree basis functions in the context of the numerical approximation of boundary value problems stemming from a minimum principle. The method is based on a variational approach, and the central idea is that the variational principle selects both the discretized physical fields and the discretization parameters, here those defining the support size of each basis function. We consider local maximum‐entropy approximation schemes, which exhibit smooth basis functions with respect to both space and the discretization parameters (the node location and the locality parameters). We illustrate by the Poisson, linear and non‐linear elasticity problems the effectivity of the method, which produces very accurate solutions with very coarse discretizations and finds unexpected patterns of the support size of the shape functions. Copyright © 2009 John Wiley & Sons, Ltd.
A constrained non‐linear system approach for the solution of an extended limit analysis problem
Authors: Tangaramvong S. , Tin‐Loi F. 
Published: December 2009

AbstractA number of recent papers (see, e.g. (Int. J. Mech. Sci. 2007; 49:454–465; Eur. J. Mech. A/Solids 2008; 27:859–881; Eng. Struct. 2008; 30:664–674; Int. J. Mech. Sci. 2009; 51:179–191)) have shown that classical limit analysis can be extended to incorporate such important features as geometric non‐linearity, softening and various so‐called ductility constraints. The generic formulation takes the form of a challenging (nonconvex and nonsmooth) optimization problem referred to in the mathematical programming literature as a mathematical program with equilibrium constraints (MPEC). Similar to a classical limit analysis, the aim is to compute in a single step a bound (upper bound, in the case of the extended problem) to the maximum load. The solution algorithm so far proposed to solve the MPEC is to convert it into an iterative non‐linear programming problem and attempts to process this using a standard non‐linear optimizer. Motivated by the fact that no method is guaranteed to solve such MPECs and by the need to avoid the use of an optimization approach, which is unfamiliar to most practising engineers, we propose, in the present paper, a novel numerical scheme to solve the MPEC as a constrained non‐linear system of equations. We illustrate the application of this approach using the simple class of elastoplastic softening skeletal structures for which certain ductility conditions are prescribed. Copyright © 2009 John Wiley & Sons, Ltd.