bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stem Cell Microenvironments ‐ Unveiling the Secret of How Stem Cell Fate is Defined
Authors: Votteler Miriam , Kluger Petra J. , Walles Heike , Schenke‐Layland Katja 
Published: August 2010

AbstractStem cells are defined as unspecialized cells that are capable of long term self‐renewal and differentiation into specialized cell types. These unique properties make them an attractive cell source for regenerative medicine applications. Although the functions of various stem cells have been extensively studied in the development of organisms and in diseases, the specific factors and conditions that control stem cell fate, specifically the conditions that allow them to remain unspecialized, are not well studied. It has been suggested that adult stem cell survival and maintenance, as well as proliferation and differentiation, are controlled by the three‐dimensional (3D) microenvironment, the so‐called niche. Major functional niche components include supporting niche cells, growth‐modulating soluble factors stored within the niches, and the extracellular matrix (ECM). In this article, we review work highlighting the growing complexity of stem cell‐ECM interactions and their impact on the fields of biomaterials research and regenerative medicine.
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The Use of Fibrous, Supramolecular Membranes and Human Tubular Cells for Renal Epithelial Tissue Engineering: Towards a Suitable Membrane for a Bioartificial Kidney
Authors: Dankers Patricia Y. W. , Boomker Jasper M. , der Vlag Ali Huizinga‐van , Smedts Frank M. M. , Harmsen Martin C. , van Luyn Marja J. A. 
Published: August 2010

AbstractA bioartificial kidney, which is composed of a membrane cartridge with renal epithelial cells, can substitute important kidney functions in patients with renal failure. A particular challenge is the maintenance of monolayer integrity and specialized renal epithelial cell functions ex vivo. We hypothesized that this can be improved by electro‐spun, supramolecular polymer membranes which show clear benefits in ease of processability. We found that after 7 d, in comparison to conventional microporous membranes, renal tubular cells cultured on top of our fibrous supramolecular membranes formed polarized monolayers, which is prerequisite for a well‐functioning bioartificial kidney. In future, these supramolecular membranes allow for incorporation of peptides that may increase cell function even further.
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Effects of alloying elements, microstructure, and inclusions on hydrogen induced cracking of X120 pipeline steel in wet H2S sour environment
Authors: Huang F. , Li X. G. , Liu J. , Qu Y. M. , Du C. W. 
Published: August 2010

AbstractHydrogen induced cracking (HIC) behavior of X120 pipeline steel with different amounts of Mn and Al was investigated using NACE standard TM0284‐2005 and back‐scattered electron imaging (BSE). The results demonstrated that inclusions and microstructure play significant roles in HIC susceptibility in X120 steels. The more the area and volume fraction of inclusions in the steel, the more the steel is susceptible to HIC. Three types of inclusions exist in the tested X120 steel and they play different roles in cracking. The critical size resulting in HIC cracks for pure MnS inclusions or mixed inclusions (inclusion clusters mainly composed of two or three different phases and compounds) of Mn/Al ratio >1 is smaller than that of pure Al2O3 inclusions or mixed inclusions of Mn/Al ratio <1. No HIC crack was observed at inclusions enriched in Si. The microstructure containing lath bainite and martensite/austenite (M/A) microconstituents is more susceptible to HIC than that with granular bainite and ferrite.
Preparation of Crosslinked Poly(2‐bromoethyl methacrylate) Microspheres and Decoration of Their Surfaces with Functional Polymer Brushes
Authors: Karagoz Bunyamin , Gunes Deniz , Bicak Niyazi 
Published: August 2010

AbstractSynthesis and crosslinking copolymerization of 2‐bromoethylmethacrylate in aqueous suspension is described for preparing bromoalkyl‐functional microbeads (125–420 µm). Highly transparent microspheres with a density of accessible bromoethyl groups of 1.55 mmol · g−1 were prepared in the suspension, stabilized with poly(N‐vinyl pyrrolidone), by using methyl methacrylate as diluting co‐monomer and ethylene glycol dimethacrylate as crosslinker. Bromoalkyl groups on the microparticles were employed as initiation sites for either surface‐initiated ATRP of glycidyl methacrylate or ring‐opening polymerization of 2‐methyl‐2‐oxazoline to generate epoxy‐ and N‐acetylethyleneimine‐functional hairy grafts, tethered to the particle surfaces with hydrolytically stable linkages.magnified image
Reconstruction of Achiral Polymer for Structural Chirality Using Cholesteric Liquid Crystal Medium and Light‐Driven Chiroptic Modulation
Authors: Goto Hiromasa , Ohta Reina 
Published: August 2010

AbstractA series of optically inactive polythiophene derivatives bearing the azobenzene moiety are synthesized in an isotropic toluene solution. The polymers are then dissolved in a cholesteric liquid crystal (Ch*LC) medium within the liquid crystal (LC) temperature range. The dissolution process in Ch*LC produces intermolecular π‐stacking with structural chirality. Although the polymers thus prepared have no chiral center or axial chirality in the primary structure, they do exhibit consistent chiroptical activity derived from three‐dimensional chiral aggregations. Furthermore, photochemical cis–trans isomerization of the substituents allows light‐driven chiroptic modulation of the polymer.
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Synthesis of Well‐Defined Statistical and Diblock Copolymers of Acrylamide and Acrylic Acid by Inverse Miniemulsion Raft Polymerization
Authors: Ouyang Liu , Wang Lianshi , Schork F. Joseph 
Published: August 2010

AbstractWell‐defined statistical and diblock copolymers with acrylamide and acrylic acid were synthesized by inverse miniemulsion RAFT polymerization. Statistical copolymers with various composition ratios were synthesized. Compositional drift was observed during polymerization. Acrylamide was polymerized with a water‐soluble initiator (VA‐044) at 60 °C to give the RAFT‐agent‐containing acrylamide homopolymer with a narrow molecular‐weight distribution (PDI < 1.3), which was then chain‐extended with acrylic acid to obtain the diblock copolymer.magnified image
A New Dithienylbenzotriazole‐Based Poly(2,7‐carbazole) for Efficient Photovoltaics
Authors: Peng Bo , Najari Ahmed , Liu Bo , Berrouard Philippe , Gendron David , He Yuehui , Zhou Kechao , Zou Yingping , Leclerc Mario 
Published: August 2010

AbstractA new dithienyl benzotriazole‐based conjugated polymer was synthesized by Suzuki coupling reaction. The polymer was found to be soluble in common organic solvents, such as chloroform, tetrahydrofuran and chlorobenzene, with excellent film‐forming properties. The structure of the polymer was confirmed by 1H NMR, the molecular weights determined by GPC and the thermal properties investigated by TGA and DSC. The polymer films exhibited an absorption band in the wavelength range 300 to 610 nm. Preliminary photovoltaic cells based on the composite structure of indium tin oxide (ITO)/PEDOT:PSS/PCDTBTz:PC60BM (1:2 w/w)/Al showed an open‐circuit voltage of 0.92 V, a power conversion efficiency of 2.2% and a short circuit current of 5.33 mA cm−2.magnified image
Mesophase Tractable Metallopolymers Based on a Metal Carboxylate Backbone Prepared by Drastic Solid‐to‐Solid Transformation within Solvothermal Synthesis
Authors: Choi Eun‐Young , Lee Hong‐Jun , Gao Chunji , Kwon O‐Pil , Lee Suck‐Hyun 
Published: August 2010

AbstractA series of layer‐structured zinc‐containing metallopolymers were prepared through a solvothermal reaction of zinc acetate with 1,4‐benzene dicarboxylic acid derivatives bearing various nonpolar n‐alkyl groups as side chains. The resulting metallopolymers were investigated. The reaction time and the length of the alkyl substituents on the backbone have a marked effect on the mesophase structure and thermal behaviors of the metallopolymers. The metallopolymer with tetradecyloxy side chains prepared by solid‐to‐solid transformations within solvothermal synthesis exhibits a unique mesophasic behavior with melt tractability.magnified image
Surface Modification of PVC Membranes Using Fluorothiophenol Compounds
Authors: Corrales Marta , Bierbrauer Karina , Sacristan Javier , Mijangos Carmen 
Published: August 2010

AbstractThe controlled chemical surface modification of PVC films by means of three fluoride aromatic compounds, 4‐fluoro thiophenol, 3,4‐difluorothiophenol and penta fluorothiophenol is reported. To obtain information about the surface selectivity of the reactions, the degree of modification of the polymer across the film was determined by depth profiling carried out using confocal Raman microscopy. It is shown that the gradient of the modification degree and the surface selectivity depend on the relationship between the rate constants of the substitution reaction and the diffusion process of the reactant. Therefore it is function of reaction time, temperature and the proportion of solvent/non‐solvent used for the reaction.magnified image
Impact Modification of Polylactide with a Biodegradable Ethylene/Acrylate Copolymer
Authors: Afrifah Kojo A. , Matuana Laurent M. 
Published: August 2010

AbstractThe effectiveness and efficiency of an ethylene/acrylate copolymer in toughening semicrystalline and amorphous PLA through melt blending is studied. The mechanical properties, phase morphologies, miscibilities, and toughening mechanisms of the blends are assessed. The ethylene/acrylate impact modifier effectively improved the impact strength of the blends, regardless of the PLA type. The semicrystalline blends showed decreased tensile strength and modulus with increased impact modifier content. In contrast, the ductility, elongation at break, and energy to break increased significantly. The relatively low BDT temperature obtained for the PLA blends renders the ethylene/acrylate copolymer impact modifier a desirable additive to toughen PLA for use in cold temperatures.magnified image
Block Copolymer Directed Nanoporous Metal Thin Films
Authors: Arora Hitesh , Li Zihui , Sai Hiroaki , Kamperman Marleen , Warren Scott C. , Wiesner Ulrich 
Published: August 2010

AbstractPorous metal thin films have high potential for use in applications such as catalysis, electrical contacts, plasmonics, as well as energy storage and conversion. Structuring metal thin films on the nanoscale to generate high surface areas poses an interesting challenge as metals have high surface energy. In this communication, we demonstrate direct access to nanostructured metal nanoparticle hybrid thin films with high nanoparticle loadings through spin coating of a mixture of block copolymer and ligand stabilized platinum and palladium nanoparticles. Plasma cleaning to remove the organics results in a conductive metal thin film. We expect that the methods described here can be generalized to other metals, mixtures of metal nanoparticles, and intermetallics.magnified image
Crystalline/Crystalline Phase Transitions in Polymer Systems Consisting of Finite‐Size Crystals in Each Crystalline Phase: Generalized Gibbs‐Thomson Equation
Authors: Hirami Matsuo 
Published: August 2010

AbstractFor polymer systems of two crystalline phases of one polymer component, each phase being consisted of polymer crystals of a finite size, we derive the crystalline‐crystalline phase transition relationship, i.e., generalized Gibbs‐Thomson equation. Its application combined with the crystalline‐liquid transition relationship (usual Gibbs‐Thomson equation) to the phase behavior of PT phase diagram of polyethylene (PE) is investigated, where the orthorhombic‐hexagonal phase transition of PE crystal under high pressure being involved. Comparison with experimental data leads to the estimates of the structural characteristics such as the ratios of (the end surface free energy of polymer crystal/crystal length) for the respective crystalline phases.magnified image
Dietary calcium decreases plasma cholesterol by down‐regulation of intestinal Niemann–Pick C1 like 1 and microsomal triacylglycerol transport protein and up‐regulation of CYP7A1 and ABCG 5/8 in hamsters
Authors: Ma Ka Ying , Yang Nan , Jiao Rui , Peng Cheng , Guan Lei , Huang Yu , Chen Zhen‐Yu 
Published: August 2010

AbstractScope: It has been shown that calcium supplementation favorably modifies plasma lipoprotein profile in postmenopausal women. The present study investigated the interaction of dietary calcium with genes of transporters, receptors and enzymes involved in cholesterol metabolism.Methods and results: Forty‐eight ovariectomized hamsters were fed one of the four diets containing 0, 2, 6 and 8 g calcium per kg. Plasma total cholesterol (TC), triacylglycerols (TG), and non‐high density lipoprotein cholesterol were dose‐dependently decreased, whereas high‐density lipoprotein cholesterol (HDL‐C) was dose‐dependently increased with the increasing dietary calcium levels. Dietary calcium had no effect on protein mass of hepatic sterol regulatory element binding protein‐2 (SREBP), liver X receptor‐alpha (LXR), 3‐hydroxy‐3‐methylglutaryl‐CoA reductase (HMGR), LDL receptor (LDLR) and cholesterol‐7α‐hydroxylase (CYP7A1). However, dietary calcium up‐regulated the mRNA levels of hepatic CYP7A1 and intestinal ATP binding cassette transporters (ABCG5/8) whereas it down‐regulated the intestinal Niemann‐Pick C1 like 1 (NPC1L1) and microsomal triacylglycerol transport protein (MTP). In addition, dietary calcium increased the activity of intestinal acyl coenzyme A: cholesterol acyltransferase 2, while it decreased plasma cholesteryl ester transport protein (CETP).Conclusion: Beneficial modification of lipoprotein profile by dietary calcium was mediated by sequestering bile acid absorption and enhancing excretion of fecal cholesterol, via up‐regulation of mRNA CYP7A1 and intestinal ABCG 5/8 with down‐regulation of mRNA NPC1L1 and MTP.
High‐field continuous arterial spin labeling with long labeling duration: Reduced confounds from blood transit time and postlabeling delay
Authors: Lu Hanbing , Leoni Renata , Silva Afonso C. , Stein Elliot A. , Yang Yihong 
Published: August 2010

AbstractIn quantitative perfusion imaging using arterial spin labeling, variable blood transit times and postlabeling delays are two confounding factors that may compromise the accuracy of perfusion quantifications. In this study, theoretical analyses and experimental data at 9.4 T demonstrate that increasing labeling duration not only enhances the contrast of the arterial spin labeling signal but also minimizes the effect of variable postlabeling delays in multislice arterial spin labeling acquisitions. With a labeling duration of 6.4 sec, arterial spin labeling signal acquired in multislice mode (11 slices) is very similar to that acquired in single‐slice mode. Previous studies have shown that inserting a delay between the spin labeling pulse and the image acquisition pulse could reduce confounds resulting from variable blood transit times at the expense of arterial spin labeling sensitivity. Our simulations suggest that enhancing the contrast of arterial spin labeling signal offers the opportunity for extending the postlabeling delay to a longer duration, minimizing systematic errors associated with a wide range of blood transit times, which could have significant implications for applying arterial spin labeling techniques to perfusion imaging of pathological conditions in animal models. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Prenatal diagnosis and follow‐up of 23 cases of cardiac tumors
Authors: Niewiadomska‐Jarosik Katarzyna , Stańczyk Jerzy , Janiak Katarzyna , Jarosik Piotr , Moll Jacek Jan , Zamojska Justyna , Respondek‐Liberska Maria 
Published: August 2010

AbstractObjectiveTo evaluate the prenatal characteristics and postnatal outcome of cardiac tumors diagnosed at two prenatal Polish cardiology centers.MethodsDescriptive analysis of 23 fetuses with cardiac tumors (12 multiple and 11 single) diagnosed over 16 years (from 1993 to 2009). Congestive heart failure was diagnosed when the cardiovascular profile score was seven or less.ResultsAssociated structural congenital heart defects were present in three fetuses, extracardiac anomalies in three, and chromosomal anomalies in two. Congestive heart failure developed in five cases. Perinatal survival was not different between cases with and without cardiac failure (2/5 vs 12/18, p = 0.28). The main ultrasonographic signs observed prenatally in association with cardiac tumors were cardiomegaly, left ventricular outflow tract obstruction, pericardial effusion, and hypokinesis. A diagnosis of tuberous sclerosis was eventually made in all 12 fetuses with multiple tumors. Perinatal death occurred in 4/11 cases with single tumors and in 5/12 with multiple tumors (p = 0.57). Surgical resection of the tumor was performed in 3/11 neonates with single tumors (histopathologically: rhabdomyoma, teratoma, and fibroma) and in 2/12 with multiple tumors (both rhabdomyomas).ConclusionsSurvival is not different between neonates with single and multiple tumors and between those with and without congestive heart failure. Copyright © 2010 John Wiley & Sons, Ltd.
Prevalence of steroid sulfatase deficiency in California according to race and ethnicity
Authors: Craig Wendy Y. , Roberson Marie , Palomaki Glenn E. , Shackleton Cedric H. L. , Marcos Josep , Haddow James E. 
Published: August 2010

AbstractObjectiveEstimate steroid sulfatase deficiency (STSD) prevalence among California's racial/ethnic groups using data from a previous study focused on prenatal detection of Smith‐Lemli‐Opitz syndrome (SLOS). SLOS and STSD both have low maternal serum unconjugated estriol (uE3) levels.MethodsPrevalence was estimated using three steps: listing clinically identified cases; modeling STSD frequency at three uE3 intervals using diagnostic urine steroid measurements; applying this model to determine frequency in pregnancies not providing urine.ResultsOverall, 2151 of 777 088 pregnancies (0.28%) were screen positive; 1379 of these were explained and excluded. Fifty‐four cases were diagnosed clinically among 707 remaining pregnancies with a male fetus. Urine steroid testing identified 74 additional STSD cases: 66 (89.2%) at uE3 values < 0.15 MoM, 8 (10.8%) at 0.15–0.20 MoM, and 0 (0%) at > 0.20 MoM. Modeling estimated 107.5 STSD cases among 370 pregnancies without urine samples. In males, STSD prevalence was highest among non‐Hispanic Whites (1:1230) compared to Hispanics (1:1620) and Asians (1:1790), but differences were not significant. No STSD pregnancies were found among 65 screen positive Black women.ConclusionThe overall prevalence estimate of 1:1500 males is consistent with published estimates and is reasonable for counseling, except among Black pregnancies where no reliable estimate could be made. Copyright © 2010 John Wiley & Sons, Ltd.
Survey of diabetes centres 2009
Authors: Hawthorne G , Gosden C 
Published: August 2010

AbstractIn the 1990s the development of diabetes centres was regarded as one of the major advances in diabetes care. With today's emphasis on service redesign and reconfiguration, this survey set out to explore the role of diabetes centres in the 21st century.The survey found that a minimum standard for the term ‘diabetes centre’ needs to be defined and that out of hours support/access for people with diabetes was limited. Diabetes centres supported high quality multidisciplinary team working and this was facilitated by the team being co‐located. Many of the medical consultants had dual roles with acute trusts that included responsibilities for acute medicine, so easy access to acute trusts facilitated effective use of medical time. The future key role for diabetes centres is to be the hub for integration of diabetes services and actively support primary and community diabetes care. Copyright © 2010 John Wiley & Sons.
Hyperglycaemia as a result of stress and possible drug interactions: a case report
Authors: Puttanna A , Cunningham AR , Scanlon JEM 
Published: August 2010

AbstractWe report the case of a six‐year‐old male paediatric patient diagnosed with type 1 diabetes following an emergency department admission for treatment of an asthma attack.The patient's elevated blood glucose level of 22.9mmol/L was consistent with current guidelines for the diagnosis of diabetes. However, he remained on the same dose of insulin for three years (despite steady, normal growth). During this time he had no problems with blood glucose control and no hypoglycaemic attacks. The diagnosis of diabetes was, therefore, questioned. The values for steroid induced hyperglycaemia were markedly higher in this patient than anecdotal values. This prompted the suspicion that the steroid induced hyperglycaemia had been further exacerbated by salbutamol administration in the setting of an acute stress response.The findings of this case illustrate the importance of understanding drug induced hyperglycaemia in the presence of intercurrent illness. Copyright © 2010 John Wiley & Sons.
From history to reality: sodium glucose co‐transporter 2 inhibitors – a novel therapy for type 2 diabetes mellitus
Authors: Nair S , Joseph F , Ewins D , Wilding J , Goenka N 
Published: August 2010

AbstractThe human kidney has a key role in the regulation of blood glucose predominantly by reabsorption of glucose from the glomerular filtrate via sodium glucose co‐transporter 2 (SGLT‐2) channels. These are expressed in the proximal renal tubules and are blocked by SGLT‐2 inhibitors, which are novel pharmacological agents currently in development. Specific SGLT‐2 inhibition results in significant increases in renal glucose excretion causing a net calorie loss and consequent weight loss, coupled with a lowering of blood glucose due to removal of glucose from the circulation. The main side effect of SGLT‐2 inhibitors appears to be an increase in genital infections, although concerns remain about the potential adverse effects of dehydration and electrolyte imbalance. Dapagliflozin is the SGLT‐2 inhibitor that is the furthest along in development, and is currently in phase III clinical trials.In this review article we consider the role of the kidney in glucose homeostasis in normal and diabetic subjects. We also review the history and concept of SGLT‐2 inhibition, and discuss the future potential clinical utility of this promising new class of drugs. Copyright © 2010 John Wiley & Sons.
Thermal Sensitivity of HMX Crystals and HMX‐Based Explosives Treated under Various Conditions
Authors: Zhang Chaoyang , Peng Qiang , Wang Liyan , Wang Xiaochuan 
Published: August 2010

AbstractThe Five‐Second Explosion Point (5‐SEP) tests and the SEM detections in this research showed that the HMX crystals and the HMX‐based explosives treated under different conditions can possess different thermal sensitivities. That is to say, higher impurity, smaller granularity, and worse integrity of HMX crystals can make them more thermally sensitive. The addition of metal or metal oxide particles, especially nanoparticles to HMX can also enhance its thermal sensitivity. Meanwhile, coating of HMX crystals with polymers to form perfect PBX and to keep them undamaged are helpful to decrease their thermal sensitivity. Furthermore, the thermal sensitivity of temperature‐aged HMX changes differently in terms of the integrity of its particles. Therefore, it can be concluded that conditions which increase the surface energy of HMX crystals or which make the HMX molecules more active to decompose at lower temperature will increase the thermal sensitivity of HMX. Additionally, the variation in the thermal sensitivity of HMX treated under different conditions is generally more temperate than that of its mechanical sensitivity.