bluuebunny/crossref_metadata_2025_split huggingface dataset:
Foam injection molding of poly(lactic) acid: Effect of back pressure on morphology and mechanical properties
Authors: Volpe Valentina , Pantani Roberto 
Published: July 2015

ABSTRACTFoam injection molding is a processing technology applied to produce a plastic part of a well‐defined shape, containing a significant fraction of voids and thus consuming less material without sacrificing mechanical properties. This technology is particularly interesting for biodegradable polymers and in particular for poly(lactic acid), PLA, since it can be adopted to save material and to avoid thermal degradation due to its high viscosity at high shear rates, which requires high temperatures in traditional injection molding process. In this work a traditional injection molding machine, modified just in the cylinder to allow the gas injection, was adopted to obtain foam injection molding of a PLA grade. In particular, the effect of back pressure on foaming was assessed. Back pressure is the pressure imposed at the back of the screw when it is returning back to prepare a new amount of material to be injected (batching phase) and thus is particularly relevant in the formation of the polymer−gas mixture. It was shown that on increasing the back pressure the percentage of foaming agent inside the injection chamber is smaller, and thus foaming is less effective. The obtained samples were characterized as far as density and mechanical properties are concerned and it was found that it was possible to reduce the density of about 25% without a significant loss of mechanical properties. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42612.
Isolation and Characterization of Multipotential Mesenchymal Stromal Cells from Congenital Pseudoarthrosis of the Tibia: Case Report
Authors: Diaz‐Solano Dylana , Wittig Olga , Mota Jose D. , Cardier Jose E. 
Published: July 2015

ABSTRACTCongenital pseudoarthrosis of the tibia (CPT) is an uncommon disease whose etiology and pathogenesis is unknown. Several evidences suggest that decreased osteogenic capacities, impaired local vascularization, and microenvironment alterations may play a role in the pathogenesis of CPT. Additionally, it is not clear if the pathogenesis of this disease is related to the absence of cells with osteogenic capacity of differentiation. In this work, a two‐year‐old patient diagnosed with CPT underwent an orthopedic surgery to promote bone union in a pseudoarthrosis lesion. Tissue from CPT lesion was excised, and histological evaluation and tissue culture were performed. Histologic analysis of the soft CPT lesion showed the presence of highly cellular fibrous tissue, vascularization, and abundant extracellular matrix. Fusiform cells of mesenchymal appearance were observed but osteoblasts, osteoclasts, chondrocytes, and adipose cells were not found. There was no evidence of osteogenesis. CPT tissue cultured as explants showed, after one month of culture, evidence of osteogenesis, chondrogenesis, and adipogenesis. Cells isolated from explants of CPT tissue showed a fibroblast‐like morphology and expressed the mesenchymal stromal cell (MSC) markers: CD105, CD73, and CD90 (CPT‐MSC). Functional analysis showed that CPT‐MSC differentiate, in vitro, into osteogenic, chondrogenic, and adipocytic cells. CPT‐MSC expressed osteocalcin and agrecan. CPT‐MSC produced collagen in the presence of ascorbic acid. MSC from BM of normal individuals were used as control. In summary, our results indicate that CPT tissue contains MSC with osteogenic capacity of differentiation. It is possible that CPT microenvironment may contribute to impair the osteogenic capacity of differentiation of CPT‐MSC. Anat Rec, 298:1804–1814, 2015. © 2015 Wiley Periodicals, Inc.
Direct Power Control of Dfig by Using Nonlinear Model Predictive Controller
Authors: Kalamian Nasrin , Verij Kazemi Mohammad , Gholomian S. Asghar 
Published: July 2015

AbstractThis paper proposes a nonlinear model predictive direct power control (PDPC) strategy for a double fed induction generator (DFIG)‐based wind energy generation system. Active and reactive power variations of DFIG are calculated based on machine rules, and a nonlinear model of DFIG is given. A nonlinear model predictive controller (NMPC) is presented based on the useful cost function and constraint that it results in more proximity between simulations and reality. The power and current ripples are reduced and the optimal rotor voltage is generated based on an objective function and the constraints. The rotor voltage vector is calculated in the synchronous reference frame and transferred into the rotor reference frame. Simulation results of a 2 MW DFIG system show good performance of the proposed method during variation of active and reactive powers, machine parameters, and wind speed. Also, the transient responses of active and reactive powers are within a few milliseconds.
Prokaryotic and Eukaryotic Aryl Sulfotransferases: Sulfation of Quercetin and Its Derivatives
Authors: Purchartová Kateřina , Valentová Kateřina , Pelantová Helena , Marhol Petr , Cvačka Josef , Havlíček Libor , Křenková Alena , Vavříková Eva , Biedermann David , Chambers Christopher S. , Křen Vladimír 
Published: July 2015

AbstractTwo types of sulfotransferases, namely recombinant rat liver aryl sulfotransferase AstIV and bacterial aryl sulfotransferase from Desulfitobacterium hafniense, were used for the sulfation of quercetin, its glycosylated derivatives (isoquercitrin and rutin), and dihydroquercetin ((+)‐taxifolin). The rat liver enzyme was able to sulfate only quercetin and taxifolin, whereas the quercetin glycosides remained intact. The D. hafniense enzyme sulfated isoquercitrin and rutin selectively at the C‐4′ position of the catechol moiety with very good yields. Taxifolin was sulfated at the C‐4′ position and a minor amount of the C‐3′ isomer was formed. Sulfation of quercetin proceeded preferentially at the C‐3′ position, but a lower proportion of the C‐4′ isomer was formed as well. A detailed analysis of the kinetics of this reaction is provided and a full structural analysis of all products is presented.
Quantitative Analysis of HAADF–STEM Images of MoVTeTaO M1 Phase Catalyst for Propane Ammoxidation to Acrylonitrile
Authors: Woo Jungwon , Borisevich Albina , Koch Christoph , Guliants Vadim V. 
Published: July 2015

AbstractHigh‐angle annular dark‐field scanning transmission electron microscopy (HAADF–STEM) image simulations were performed to determine accurate metal distributions in the MoVTeTaO M1 phase catalyst for propane ammoxidation. QSTEM simulation, based on a multislice method with the frozen phonon approximation, was chosen because of the excellent agreement between experimental and simulated HAADF–STEM images. This simulation method successfully provided accurate metal distributions in the MoVTeTaO M1 phase and indicated significantly lower V occupancies of the linking sites 1, 2, 3, 4, and 7, and higher Ta occupancy in site 9 than the previously reported metal occupancies. This novel methodology for accurate HAADF–STEM image analysis is a valuable tool for accurate analysis of local chemical compositions in a wide range of ordered catalytic materials.
Fast X‐ray Tomographic Microscopy: Investigating Mechanisms of Performance Drop during Freeze Starts of Polymer Electrolyte Fuel Cells
Authors: Mayrhuber Immanuel , Marone Federica , Stampanoni Marco , Schmidt Thomas J. , Büchi Felix N. 
Published: July 2015

AbstractThe success of a freeze start of a polymer electrolyte fuel cell depends on the state and spatial distribution of the water produced in the porous structures of the membrane electrode assembly (MEA), namely, the gas diffusion and catalyst layers. To improve understanding of performance loss that occurs during freeze starts, the water/ice phase is imaged in the MEA by means of X‐ray tomographic microscopy at temperatures between −10 and −20 °C. As the duration of the isothermal freeze starts can be as short as 20 s before a performance drop occurs, the acquisition time for one tomographic scan is reduced to only 4.9 s. Interpretation of the images and the voltage transients show three different mechanisms for the performance drop. The main difference between the three mechanisms is the lack or appearance of supercooled water in the gas diffusion layer. Fast X‐ray imaging is well suited to solve this challenge.
Selective Halogenation Using an Aniline Catalyst
Authors: Samanta Ramesh C. , Yamamoto Hisashi 
Published: July 2015

AbstractElectrophilic halogenation is used to produce a wide variety of halogenated compounds. Previously reported methods have been developed mainly using a reagent‐based approach. Unfortunately, a suitable “catalytic” process for halogen transfer reactions has yet to be achieved. In this study, arylamines have been found to generate an N‐halo arylamine intermediate, which acts as a highly reactive but selective catalytic electrophilic halogen source. A wide variety of heteroaromatic and aromatic compounds are halogenated using commercially available N‐halosuccinimides, for example, NCS, NBS, and NIS, with good to excellent yields and with very high selectivity. In the case of unactivated double bonds, allylic chlorides are obtained under chlorination conditions, whereas bromocyclization occurs for polyolefin. The reactivity of the catalyst can be tuned by varying the electronic properties of the arene moiety of catalyst.
Complex karyotype is a stronger predictor than del(17p) for an inferior outcome in relapsed or refractory chronic lymphocytic leukemia patients treated with ibrutinib‐based regimens
Authors: Thompson Philip A. , O'Brien Susan M. , Wierda William G. , Ferrajoli Alessandra , Stingo Francesco , Smith Susan C. , Burger Jan A. , Estrov Zeev , Jain Nitin , Kantarjian Hagop M. , Keating Michael J. 
Published: July 2015

BACKGROUNDIbrutinib is active in patients with relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL). In patients treated with ibrutinib for R/R CLL, del(17p), identified by interphase fluorescence in situ hybridization (FISH), is associated with inferior progression‐free survival despite equivalent initial response rates. Del(17p) is frequently associated with a complex metaphase karyotype (CKT); the prognostic significance of CKT in ibrutinib‐treated patients has not been reported.METHODSThis study reviewed 88 patients treated for R/R CLL at The University of Texas MD Anderson Cancer Center with investigational ibrutinib‐based regimens from 2010 to 2013. Pretreatment FISH and lipopolysaccharide‐stimulated metaphase cytogenetic analysis were performed on bone marrow.RESULTSAn adequate pretreatment metaphase karyotype was available for 56 of the 88 patients. The karyotype was complex in 21 of the 56 cases; 17 of the 21 had del(17p) according to FISH. The overall response rate, including partial remission with persistent lymphocytosis, was 94%; 18% had complete responses. In a multivariate analysis (MVA), only CKT was significantly associated with event‐free survival (EFS; hazard ratio [HR], 6.6 [95% CI 1.7‐25.6]; P = .006). Fludarabine‐refractory CLL (HR, 6.9 [95% CI 1.8‐27.1], P = .005) and CKT (HR 5.9 [95% CI 1.6‐22.2], P = .008) were independently associated with inferior overall survival (OS) in MVA. Del(17p) by FISH was not significantly associated with EFS or OS in MVA.CONCLUSIONSCKT is a powerful predictor of outcomes for ibrutinib‐treated patients with R/R CLL and may be a stronger predictor of biological behavior than del(17p) by FISH. Because of their relatively poor outcomes, patients with CKT are ideal candidates for studies of consolidative treatment strategies or novel treatment combinations. Cancer 2015 © 2015 American Cancer Society. Cancer 2015;121:3612–3621. © 2015 American Cancer Society.
miR‐124 Contributes to the functional maturity of microglia
Authors: Svahn Adam J. , Giacomotto Jean , Graeber Manuel B. , Rinkwitz Silke , Becker Thomas S. 
Published: July 2015

ABSTRACTDuring early development of the central nervous system (CNS), a subset of yolk‐sac derived myeloid cells populate the brain and provide the seed for the microglial cell population, which will self‐renew throughout life. As development progresses, individual microglial cells transition from a phagocytic amoeboid state through a transitional morphing phase into the sessile, ramified, and normally nonphagocytic microglia observed in the adult CNS under healthy conditions. The molecular drivers of this tissue‐specific maturation profile are not known. However, a survey of tissue resident macrophages identified miR‐124 to be expressed in microglia. In this study, we used transgenic zebrafish to overexpress miR‐124 in the mpeg1 expressing yolk‐sac‐derived myeloid cells that seed the microglia. In addition, a systemic sponge designed to neutralize the effects of miR‐124 was used to assess microglial development in a miR‐124 loss‐of‐function environment. Following the induction of miR‐124 overexpression, microglial motility and phagocytosis of apoptotic cells were significantly reduced. miR‐124 overexpression in microglia resulted in the accumulation of residual apoptotic cell bodies in the optic tectum, which could not be achieved by miR‐124 overexpression in differentiated neurons. Conversely, expression of the miR‐124 sponge caused an increase in the motility of microglia and transiently rescued motility and phagocytosis functions when activated simultaneously with miR‐124 overexpression. This study provides in vivo evidence that miR‐124 activity has a key role in the development of functionally mature microglia. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 507–518, 2016
Synthesis and NMR Spectroscopic Study of the Self‐Aggregation of 2‐Substituted Benz­ene‐1,3,5‐tricarboxamides
Authors: Invernizzi Christian , Dalvit Claudio , Stoeckli‐Evans Helen , Neier Reinhard 
Published: July 2015

AbstractThe self‐assembly of N,N′,N″‐trialkylbenzene‐1,3,5‐tricarboxamides (BTAs) 1 or of “crowded” BTAs 11 and 12 lead to supramolecular columnar‐stacked structures with attractive material properties. The introduction of three alkoxy groups is reported to reinforce the self‐assembly process. The influence of a single substituent introduced onto the aromatic core of BTA significantly affects the self‐assembly process. The aggregation process of 2‐substituted BTAs in the bulk and in solution, as studied by DSC, POM, X‐ray diffraction and 1H NMR experiments, is impaired by hydrogen‐bond‐accepting substituents but strengthened by non‐hydrogen‐bond‐accepting substituents.
α‐Oxo‐Iminoxyls of Isoxazolones, Pyrazol­ones and 1,2,3‐Triazolone
Authors: Koch Rainer , Wollweber Hans‐Joachim , Müller‐Starke Hans , Wentrup Curt 
Published: July 2015

AbstractA series of α‐oxo‐iminoxyls was obtained by PbO2 oxidation of 4‐oximinoisoxazol‐5(4H)‐ones, 4‐oximinopyrazol‐5(4H)‐ones, and 1‐phenyl‐4‐oximino‐1,2,3‐triazol‐5(4H)‐one and characterized by electron spin resonance spectroscopy in conjunction with DFT calculations of structures, energies, and hyperfine coupling constants. The iminoxyls are σ‐radicals existing largely in the Z configuration with respect to the C=O group, but minor amounts of the E isomers were observable in several cases. Couplings of the free‐radical electron with N1, N2, N3, C4 and C5 ring nuclei as well as the imine nitrogen N6 were observed, and some isomers were also observed to couple with a CH3 group in position 3 and with the ortho‐H atoms of an aryl group in position 3. The lower energies of the Z isomers relative to the E isomers can be ascribed to a stabilizing interaction between a singly occupied orbital on the oxime oxygen and a lone pair orbital on the carbonyl oxygen.
Understanding the complexities of Salmonella–host crosstalk as revealed by in vivo model organisms
Authors: Verma Smriti , Srikanth Chittur V. 
Published: July 2015

AbstractFoodborne infections caused by non‐typhoidal Salmonellae, such as Salmonella enterica serovar Typhimurium (ST), pose a major challenge in the developed and developing world. With constant rise of drug‐resistant strains, understanding the epidemiology, microbiology, pathogenesis and host–pathogen interactions biology is a mandatory requirement to enable health systems to be ready to combat these illnesses. Patient data from hospitals, at least from some parts of the world, have aided in epidemiological understanding of ST‐mediated disease. Most of the other aspects connected to Salmonella–host crosstalk have come from model systems that offer convenience, genetic tractability and low maintenance costs that make them extremely valuable tools. Complex model systems such as the bovine model have helped in understanding key virulence factors needed for infection. Simple systems such as fruit flies and Caenorhabditis elegans have aided in identification of novel virulence factors, host pathways and mechanistic details of interactions. Some of the path‐breaking concepts of the field have come from mice model of ST colitis, which allows genetic manipulations as well as high degree of similarity to human counterpart. Together, they are invaluable for correlating in vitro findings of ST‐induced disease progression in vivo. The current review is a compilation of various advances of ST–host interactions at cellular and molecular levels that has come from investigations involving model organisms. © 2015 IUBMB Life, 67(7):482–497, 2015
Dual biofunctional polymer modifications to address endothelialization and smooth muscle cell integration of ePTFE vascular grafts
Authors: Bastijanic Jennifer M. , Kligman Faina L. , Marchant Roger E. , Kottke‐Marchant Kandice 
Published: July 2015

AbstractExpanded polytetrafluoroethylene (ePTFE) grafts were coated on the luminal surface with a cell‐adhesive fluorosurfactant (FSP) polymer to promote endothelialization, followed by ethanol hydration to degas the pores and subsequent cell‐adhesive, enzymatically degradable poly(ethylene glycol)‐based hydrogel incorporation into the graft interstices to accommodate potential smooth muscle cell integration in the graft wall. The FSP coating on ePTFE was stable as demonstrated by a significantly reduced receding water contact angle on FSP‐coated ePTFE (14.5 ± 6.4°) compared to uncoated ePTFE (105.3 ± 4.5°, P < 0.05) after ethanol exposure. X‐ray photoelectron spectroscopy analysis of the same surfaces confirmed FSP presence. Localization of the FSP and hydrogel within the ePTFE graft construct was assessed using fluorescently labeled polymers, and demonstrated hydrogel infiltration throughout the thickness of the graft wall, with FSP coating limited to the lumen and adventitial surfaces. FSP at the luminal surface on dual‐coated grafts was able to bind endothelial cells (EC) (98.7 ± 23.1 cells/mm2) similar to fibronectin controls (129.4 ± 40.7 cells/mm2), and significantly higher than uncoated ePTFE (31.6 ± 19 cells/mm2, P < 0.05). These results indicate that ePTFE grafts can be simultaneously modified with two different polymers that have potential to directly address both endothelialization and intimal hyperplasia. Such a construct is a promising candidate for an off‐the‐shelf synthetic graft for small‐diameter graft applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 71–81, 2016.
Nanometer‐sized extracellular matrix coating on polymer‐based scaffold for tissue engineering applications
Authors: Uchida Noriyuki , Sivaraman Srikanth , Amoroso Nicholas J. , Wagner William R. , Nishiguchi Akihiro , Matsusaki Michiya , Akashi Mitsuru , Nagatomi Jiro 
Published: July 2015

AbstractSurface modification can play a crucial role in enhancing cell adhesion to synthetic polymer‐based scaffolds in tissue engineering applications. Here, we report a novel approach for layer‐by‐layer (LbL) fabrication of nanometer‐size fibronectin and gelatin (FN‐G) layers on electrospun fibrous poly(carbonate urethane)urea (PCUU) scaffolds. Alternate immersions into the solutions of fibronectin and gelatin provided thickness‐controlled FN‐G nano‐layers (PCUUFN‐G) which maintained the scaffold's 3D structure and width of fibrous bundle of PCUU as evidenced by scanning electron miscroscopy. The PCUUFN‐G scaffold improved cell adhesion and proliferation of bladder smooth muscles (BSMCs) when compared to uncoated PCUU. The high affinity of PCUUFN‐G for cells was further demonstrated by migration of adherent BSMCs from culture plates to the scaffold. Moreover, the culture of UROtsa cells, human urothelium‐derived cell line, on PCUUFN‐G resulted in an 11–15 μm thick multilayered cell structure with cell‐to‐cell contacts although many UROtsa cells died without forming cell connections on PCUU. Together these results indicate that this approach will aid in advancing the technology for engineering bladder tissues in vitro. Because FN‐G nano‐layers formation is based on nonspecific physical adsorption of fibronectin onto polymer and its subsequent interactions with gelatin, this technique may be applicable to other polymer‐based scaffold systems for various tissue engineering/regenerative medicine applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 94–103, 2016.
PTH Signaling in Osteoprogenitors Is Essential for B-Lymphocyte Differentiation and Mobilization
Authors: Panaroni Cristina , Fulzele Keertik , Saini Vaibhav , Chubb Rhiannon , Pajevic Paola Divieti , Wu Joy Y 
Published: July 2015

ABSTRACT

Cells of the osteoblast lineage provide critical support for B lymphopoiesis in the bone marrow (BM). Parathyroid hormone (PTH) signaling in osteoblastic cells through its receptor (PPR) is an important regulator of hematopoietic stem cells; however, its role in regulation of B lymphopoiesis is not clear. Here we demonstrate that deletion of PPR in osteoprogenitors results in a significant loss of trabecular and cortical bone. PPR signaling in osteoprogenitors, but not in mature osteoblasts or osteocytes, is critical for B-cell precursor differentiation via IL-7 production. Interestingly, despite a severe reduction in B-cell progenitors in BM, mature B-lymphocytes were increased 3.5-fold in the BM of mice lacking PPR in osteoprogenitors. This retention of mature IgD+ B cells in the BM was associated with increased expression of vascular cell adhesion molecule 1 (VCAM1) by PPR-deficient osteoprogenitors, and treatment with VCAM1 neutralizing antibody increased mobilization of B lymphocytes from mutant BM. Our results demonstrate that PPR signaling in early osteoblasts is necessary for B-cell differentiation via IL-7 secretion and for B-lymphocyte mobilization via VCAM1. © 2015 American Society for Bone and Mineral Research.
Pilot evaluation of the population pharmacokinetics of bumetanide in term newborn infants with seizures
Authors: Jullien Vincent , Pressler Ronit M. , Boylan Geraldine , Blennow Mats , Marlow Neil , Chiron Catherine , Pons Gerard ,   for the NEMO Consortium Neonatal Seizure Treatment With Medication Off‐Patent
Published: July 2015

AbstractRecent experimental data suggest bumetanide as a possible therapeutic option in newborn infants with seizures after birth asphyxia. Because pharmacokinetic (PK) data are lacking in this population, who very often benefit from therapeutic cooling, which can modify the PK behavior of a drug, a PK study was conducted in term infants with seizures caused by hypoxic‐ischemic encephalopathy. Fourteen infants were included, 13 of them being cooled. Forty‐nine blood samples were available for the determination of the plasma concentration of bumetanide. Concentration‐time data were analyzed by the use of a population approach performed with Monolix Software. Bumetanide was found to follow a 2‐compartment model. The mean values were 0.063 L/h for clearance, 0.28 and 0.44 L for the central and peripheral distribution volumes, respectively, and 0.59 L/h for the distribution clearance. Birth body weight explained the interindividual variability of bumetanide clearance via an allometric model. No relationship was found between bumetanide exposure and its efficacy (reduction in seizure burden) or its toxicity (hearing loss). This study describes the first PK model of bumetanide in hypothermia‐treated infants with seizures.