bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel Structural Changes during Temperature‐Induced Self‐Assembling and Gelation of PLGA‐PEG‐PLGA Triblock Copolymer in Aqueous Solutions
Authors: Khorshid Neda Khameh , Zhu Kaizheng , Knudsen Kenneth D. , Bekhradnia Sara , Sande Sverre Arne , Nyström Bo 
Published: October 2016

The thermoresponsive amphiphilic block copolymer poly(d,l‐lactic acid‐co‐glycolic acid)‐block‐poly(ethylene glycol)‐block‐poly(d,l‐lactic acid‐co‐glycolic acid) (PLGA‐PEGn‐PLGA), which exhibits a reversible temperature‐induced sol–gel transition at higher polymer concentrations in aqueous solution has attached a great deal of interest because of its potential in biomedical applications. In the present work, the length of the hydrophobic PLGA blocks is kept constant, whereas the length of the hydrophilic PEG block is altered and this variation has a pronounced impact on the phase behavior of the aqueous samples and the structure of the polymer. A short PEG block promotes gelation at a low temperature, whereas a longer PEG block shifts the gelation point to higher temperature. By using a combination of turbidity, rheology, and small angle neutron scattering (SANS) methods, the authors have revealed dramatic temperature effects. In dilute solution, the SANS experiments expose asymmetric ellipsoid structures for the copolymer with the short PEG‐spacer, whereas spherical core–shell structure is observed for the polymer with long PEG‐spacer. In the semidilute concentration regime, SANS measurements disclose similar profiles for the two copolymers. In a broad temperature interval, the transition from spherical core–shell micelles to cylindrical structure and packing of cylinders is observed.
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Efficient Release of Affinity‐Captured Cells Using a Coiled‐Coil‐Based Molecular Trigger
Authors: Zhang Mengen , Shen Wei 
Published: October 2016

Affinity‐based cell separation is label‐free and highly specific, but it is difficult to efficiently and gently release affinity‐captured cells due to the multivalent nature of cell‐material interactions. To address this challenge, we have developed a platform composed of a capture substrate and a cell‐releasing molecular trigger. The capture substrate is functionalized with a cell‐capture antibody and a coiled‐coil A. The cell‐releasing molecular trigger B‐PEG (polyethylene glycol), a conjugate of a coiled‐coil B and polyethylene glycol, can drive efficient and gentle release of the captured cells, because A/B heterodimerization brings B‐PEG to the substrate and PEG chains adopt extended conformations and break nearby multivalent antibody‐biomarker interactions. No enzymes or excessive shear stress are involved, and the released cells have neither external molecules attached nor endogenous cell‐surface molecules cleaved, which is critical for the viability, phenotype, and function of sensitive cells.
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Hairy Nanoparticles with Hard Polystyrene Cores and Soft Polydimethylsiloxane Shells: One‐Pot Synthesis by Living Anionic Polymerization and Characterization
Authors: Zhou Guangchang , Person Vernecia , Khan Ishrat M. 
Published: October 2016

Hairy core–shell nanoparticles have emerged as a unique class of polymeric nanocomposites. Hairy nanoparticles (HNPs) with hard polystyrene (PS) cores and soft polydimethylsiloxane (PDMS) shells have been synthesized by living anionic polymerization via “one‐pot synthesis” approach. The size and composition of both core and shell components can be controlled. The synthetic approach produces an entirely new class of HNPs. Differential scanning calorimetry thermograms of the core–shell nanoparticles show two distinct transition temperatures corresponding to a glass transition temperature (Tg) of PS segment and a melting transition temperature (Tm) of PDMS segment indicating the formation of a phase separated system. The synthesized HNPs show different morphologies dependent on the content of PDMS due to the fusion of particles. Solvents play a crucial role in the fusion of particles. Diethyl ether can reduce the fusion of particles and generate almost uniform particles. The HNPs can self‐assemble into hierarchical suprastructures. The HNPs may have potential applications in emerging industries such as high‐density microelectronic materials and lithography.
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Gamma‐Cyclodextrin‐Recognition‐Responsive Characteristics of Poly(N‐isopropylacrylamide)‐Based Hydrogels with Benzo‐12‐crown‐4 Units as Signal Receptors
Authors: Wei Yun‐Yan , Liu Zhuang , Ju Xiao‐Jie , Shi Kun , Xie Rui , Wang Wei , Cheng Zhengdong , Chu Liang‐Yin 
Published: October 2016

Molecular‐recognition‐responsive characteristics of a novel poly(N‐isopropylacrylamide‐co‐benzo‐12‐crown‐4‐acrylamide) (PNB12C4) hydrogel have been investigated. In the prepared PNB12C4 hydrogel, benzo‐12‐crown‐4 (B12C4) groups act as guest molecules and γ‐cyclodextrin (γ‐CD)‐receptors, and poly(N‐isopropylacrylamide) (PNIPAM) networks act as phase‐transition actuators. The formation of stable γ‐CD/B12C4 complexes enhances the hydrophilicity of the PNB12C4 hydrogel networks, and induces positive shift of the volume phase transition temperature (VPTT) of PNB12C4 hydrogel. Moreover, the PNB12C4 hydrogel also shows thermoresponsive adsorption property selectively towards γ‐CD. The γ‐CD‐recognition sensitivity of PNB12C4 hydrogel can be dramatically improved by increasing γ‐CD concentration in solution or B12C4 content in PNB12C4 copolymer networks. The results in this study provide valuable information for developing crown ether‐based smart materials in various applications.
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Sulforaphane epigenetically enhances neuronal BDNF expression and TrkB signaling pathways
Authors: Kim Jisung , Lee Siyoung , Choi Bo‐Ryoung , Yang Hee , Hwang Youjin , Park Jung Han Yoon , LaFerla Frank M. , Han Jung‐Soo , Lee Ki Won , Kim Jiyoung 
Published: October 2016

ScopeBrain‐derived neurotrophic factor (BDNF) is a neurotrophin that supports the survival of existing neurons and encourages the growth and differentiation of new neurons and synapses. We investigated the effect of sulforaphane, a hydrolysis product of glucoraphanin present in Brassica vegetables, on neuronal BDNF expression and its synaptic signaling pathways.Methods and resultsMouse primary cortical neurons and a triple‐transgenic mouse model of Alzheimer's disease (3 × Tg‐AD) were used to study the effect of sulforaphane. Sulforaphane enhanced neuronal BDNF expression and increased levels of neuronal and synaptic molecules such as MAP2, synaptophysin, and PSD‐95 in primary cortical neurons and 3 × Tg‐AD mice. Sulforaphane elevated levels of synaptic TrkB signaling pathway components, including CREB, CaMKII, ERK, and Akt in both primary cortical neurons and 3 × Tg‐AD mice. Sulforaphane increased global acetylation of histone 3 (H3) and H4, inhibited HDAC activity, and decreased the level of HDAC2 in primary cortical neurons. Chromatin immunoprecipitation analysis revealed that sulforaphane increased acetylated H3 and H4 at BDNF promoters, suggesting that sulforaphane regulates BDNF expression via HDAC inhibition.ConclusionThese findings suggest that sulforaphane has the potential to prevent neuronal disorders such as Alzheimer's disease by epigenetically enhancing neuronal BDNF expression and its TrkB signaling pathways.
Combinatory estrogenic effects between the isoflavone genistein and the mycotoxins zearalenone and alternariol in vitro
Authors: Vejdovszky Katharina , Schmidt Verena , Warth Benedikt , Marko Doris 
Published: October 2016

ScopeThe isoflavone genistein, present in soy‐based food and dietary supplements, is known for its estrogenic potential. In addition to phytoestrogens, food may also contain mycotoxins with estrogenic properties like zearalenone or alternariol, raising the question on potential combinatory effects of these xenoestrogens.Methods and resultsCombinatory estrogenic effects of genistein with zearalenone or alternariol were studied in the human endometrial adenocarcinoma cell line Ishikawa as expression of alkaline phosphatase (AlP) activity. Combinations of genistein with either zearalenone or alternariol, showed synergism and antagonism in the AlP assay, depending on the combination ratios and the concentration range. For combinations of zearalenone with genistein synergistic effects dominated.ConclusionWe demonstrate that mixture effects of phyto‐ and mycoestrogens potentially pose unexpected risks to consumers. Our study highlights the necessity of according considerations regarding combinatory effects in future risk assessment. The applied in vitro study design represents a cost‐efficient screening method to discover interactive effects of estrogens as a basic decision tool for priority risk assessment.
Mis‐estimation and bias of hyperpolarized apparent diffusion coefficient measurements due to slice profile effects
Authors: Gordon Jeremy W. , Milshteyn Eugene , Marco‐Rius Irene , Ohliger Michael , Vigneron Daniel B. , Larson Peder E.Z. 
Published: October 2016

PurposeThe purpose of this work was to explore the impact of slice profile effects on apparent diffusion coefficient (ADC) mapping of hyperpolarized (HP) substrates.MethodsSlice profile effects were simulated using a Gaussian radiofrequency (RF) pulse with a variety of flip angle schedules and b‐value ordering schemes. A long T1 water phantom was used to validate the simulation results, and ADC mapping of HP [13C,15N2]urea was performed on the murine liver to assess these effects in vivo.ResultsSlice profile effects result in excess signal after repeated RF pulses, causing bias in HP measurements. The largest error occurs for metabolites with small ADCs, resulting in up to 10‐fold overestimation for metabolites that are in more‐restricted environments. A mixed b‐value scheme substantially reduces this bias, whereas scaling the slice‐select gradient can mitigate it completely. In vivo, the liver ADC of hyperpolarized [13C,15N2]urea is nearly 70% lower (0.99 ± 0.22 vs 1.69 ± 0.21 × 10−3 mm2/s) when slice‐select gradient scaling is used.ConclusionSlice profile effects can lead to bias in HP ADC measurements. A mixed b‐value ordering scheme can reduce this bias compared to sequential b‐value ordering. Slice‐select gradient scaling can also correct for this deviation, minimizing bias and providing more‐precise ADC measurements of HP substrates. Magn Reson Med 78:1087–1092, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Intraindividual genomic heterogeneity of high‐grade serous carcinoma of the ovary and clinical utility of ascitic cancer cells for mutation profiling
Authors: Choi Youn Jin , Rhee Je‐Keun , Hur Soo Young , Kim Min Sung , Lee Sung Hak , Chung Yeun‐Jun , Kim Tae‐Min , Lee Sug Hyung 
Published: October 2016

AbstractIntraindividual tumoural heterogeneity (ITH) is a hallmark of solid tumours and impedes accurate genomic diagnosis and selection of proper therapy. The aim of this study was to identify ITH of ovarian high‐grade serous carcinomas (OSCs) and to determine the utility of ascitic cancer cells as a resource for mutation profiling in spite of ITH. We performed whole‐exome sequencing, copy number profiling and DNA methylation profiling of four OSC genomes by using multiregional biopsies from 13 intraovarian lesions, 12 extraovarian tumour lesions (omentum/peritoneum), and ascitic cells. We observed substantial levels of heterogeneity in mutations and copy number alterations (CNAs) of the OSCs. We categorized the mutations into ‘common’, ‘shared’ and ‘private’ according to the regional distribution. Six common, eight shared and 24 private mutations were observed in known cancer‐related genes. Common mutations had a higher mutant allele frequency, and included TP53 mutations in all four OSCs. Region‐specific chromosomal amplifications and deletions involving BRCA1, PIK3CA and RB1 were also identified. It is of note that the mutations detected in ascitic cancer cells represented 92.3–100% of overall somatic mutations in the given case. Phylogenetic analyses of ascitic genomes predicted a polyseeding origin of somatic mutations in ascitic cells. Our results demonstrate that, despite ITH, somatic mutations, CNAs and DNA methylations in both ‘common’ category and cancer‐related genes were highly conserved in ascitic cells of OSCs, highlighting the clinical relevance of genome analysis of ascitic cells. Ascitic tumour cells may serve as a potential resource for discovering somatic mutations of primary OSC with diagnostic and therapeutic relevance. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Hepcidin knockout mice spontaneously develop chronic pancreatitis owing to cytoplasmic iron overload in acinar cells
Authors: Lunova Mariia , Schwarz Peggy , Nuraldeen Renwar , Levada Kateryna , Kuscuoglu Deniz , Stützle Michael , Vujić Spasić Maja , Haybaeck Johannes , Ruchala Piotr , Jirsa Milan , Deschemin Jean‐Christophe , Vaulont Sophie , Trautwein Christian , Strnad Pavel 
Published: October 2016

AbstractIron is both an essential and a potentially toxic element, and its systemic homeostasis is controlled by the iron hormone hepcidin. Hepcidin binds to the cellular iron exporter ferroportin, causes its degradation, and thereby diminishes iron uptake from the intestine and the release of iron from macrophages. Given that hepcidin‐resistant ferroportin mutant mice show exocrine pancreas dysfunction, we analysed pancreata of aging hepcidin knockout (KO) mice. Hepcidin and Hfe KO mice were compared with wild‐type (WT) mice kept on standard or iron‐rich diets. Twelve‐month‐old hepcidin KO mice were subjected to daily minihepcidin PR73 treatment for 1 week. Six‐month‐old hepcidin KO mice showed cytoplasmic acinar iron overload and mild pancreatitis, together with elevated expression of the iron uptake mediators DMT1 and Zip14. Acinar atrophy, massive macrophage infiltration, fatty changes and pancreas fibrosis were noted in 1‐year‐old hepcidin KO mice. As an underlying mechanism, 6‐month‐old hepcidin KO mice showed increased pancreatic oxidative stress, with elevated DNA damage, apoptosis and activated nuclear factor‐κB (NF‐κB) signalling. Neither iron overload nor pancreatic damage was observed in WT mice fed iron‐rich diet or in Hfe KO mice. Minihepcidin application to hepcidin KO mice led to an improvement in general health status and to iron redistribution from acinar cells to macrophages. It also resulted in decreased NF‐κB activation and reduced DNA damage. In conclusion, loss of hepcidin signalling in mice leads to iron overload‐induced chronic pancreatitis that is not seen in situations with less severe iron accumulation. The observed tissue injury can be reversed by hepcidin supplementation. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
MIIP haploinsufficiency induces chromosomal instability and promotes tumour progression in colorectal cancer
Authors: Sun Yan , Ji Ping , Chen Tao , Zhou Xinhui , Yang Da , Guo Yuhong , Liu Yuexin , Hu Limei , Xia Dianren , Liu Yanxue , Multani Asha S , Shmulevich Ilya , Kucherlapati Raju , Kopetz Scott , Sood Anil K , Hamilton Stanley R , Sun Baocun , Zhang Wei 
Published: October 2016

AbstractThe gene encoding migration and invasion inhibitory protein (MIIP), located on 1p36.22, is a potential tumour suppressor gene in glioma. In this study, we aimed to explore the role and mechanism of action of MIIP in colorectal cancer (CRC). MIIP protein expression gradually decreased along the colorectal adenoma–carcinoma sequence and was negatively correlated with lymph node and distant metastasis in 526 colorectal tissue samples (p < 0.05 for all). Analysis of The Cancer Genome Atlas (TCGA) data showed that decreased MIIP expression was significantly associated with MIIP hemizygous deletion (p = 0.0005), which was detected in 27.7% (52/188) of CRC cases, and associated with lymph node and distant metastasis (p < 0.05 for both). We deleted one copy of the MIIP gene in HCT116 CRC cells using zinc finger nuclease technology and demonstrated that MIIP haploinsufficiency resulted in increased colony formation and cell migration and invasion, which was consistent with the results from siRNA‐mediated MIIP knockdown in two CRC cell lines (p < 0.05 for all). Moreover, MIIP haploinsufficiency promoted CRC progression in vivo (p < 0.05). Genomic instability and spectral karyotyping assays demonstrated that MIIP haploinsufficiency induced chromosomal instability (CIN). Besides modulating the downstream proteins of APC/CCdc20, securin and cyclin B1, MIIP haploinsufficiency inhibited topoisomerase II (Topo II) activity and induced chromosomal missegregation. Therefore, we report that MIIP is a novel potential tumour suppressor gene in CRC. Moreover, we characterized the MIIP gene as a novel CIN suppressor gene, through altering the stability of mitotic checkpoint proteins and disturbing Topo II activity. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Structure–property relations of nylon‐6 and polytetramethylene glycol based multiblock copolymers with microphase separation prepared through reactive processing
Authors: Kong Weibo , Yang Yunyun , Liu Zhimeng , Jiang Liang , Zhou Changlin , Lei Jingxin 
Published: October 2016

AbstractA series of poly(urethane‐urea‐amide) thermoplastic elastomers (PUUAs) based on polytetrahydrofuran (polytetramethylene glycol, PTMG), nylon‐6 and 4,4′‐diphenylmethane diisocyanate were synthesized through reactive processing. This method solved the incompatibility of nylon‐6 and PTMG, and these model elastomers were used to gain insight into the structure–property relations of block polymers. The target products were solvent resistant, transparent and melting‐processable. Fourier transform infrared spectroscopy, XRD, DSC, TEM, dynamic mechanical analysis, tensile testing and TGA were used to study the structure, crystallization, morphology, mechanical properties and thermostability of the PUUAs. The Fourier transform infrared results proved the successful preparation of PUUAs from nylon‐6 and PTMG. TEM examination showed that all samples exhibit microphase separated morphology with the nylon‐6 domain dispersed in the PTMG phase. The results of tensile testing indicated that the elastomers exhibit excellent mechanical properties with stress at break and strain at break exceeding 40 MPa and 600% respectively. The TGA results implied that the PUUAs can be fabricated by transitional processing at proper temperature without any thermodegradation. These favorable features were related to the microphase separated structure of the PUUAs. © 2016 Society of Chemical Industry
Thiol‐acrylate main‐chain liquid‐crystalline elastomers with tunable thermomechanical properties and actuation strain
Authors: Saed Mohand O. , Torbati Amir H. , Starr Chelsea A. , Visvanathan Rayshan , Clark Noel A. , Yakacki Christopher M. 
Published: October 2016

ABSTRACTThe purpose of this study was to investigate the influence of cross‐linking on the thermomechanical behavior of liquid‐crystalline elastomers (LCEs). Main‐chain LCE networks were synthesized via a thiol‐acrylate Michael addition reaction. The robust nature of this reaction allowed for tailoring of the behavior of the LCEs by varying the concentration and functionality of the cross‐linker. The isotropic rubbery modulus, glass transition temperature, and strain‐to‐failure showed strong dependence on cross‐linker concentration and ranged from 0.9 MPa, 3 °C, and 105% to 3.2 MPa, 25 °C, and 853%, respectively. The isotropic transition temperature (Ti) was shown to be influenced by the functionality of the cross‐linker, ranging from 70 °C to 80 °C fortri‐ andtetra‐functional cross‐linkers. The magnitude of actuation can be tailored by controlling the amount of cross‐linker and applied stress. Actuation increased with increased applied stress and decreased with greater amounts of cross‐linking. The maximum strain actuation achieved was 296% under 100 kPa of bias stress, which resulted in work capacity of 296 kJ/m3for the lowest cross‐linked networks. Overall, the experimental results provide a fundamental insight linking thermomechanical properties and actuation to a homogenous polydomainnematicLCE networks with order parameters of 0.80 when stretched. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys.2017,55, 157–168
Unusual dynamics of ring probes in linear matrices
Authors: Shanbhag Sachin 
Published: October 2016

ABSTRACTWe perform Monte Carlo simulations of ring and linear polymers in linear matrices, and investigate the diffusivity of the probes. As the matrix chain length Nm is increased from 10 to 300 monomers, the diffusivity Dl of a linear probe (Nl = 300) decreases monotonically, while that of a ring probe Dr varies non‐monotonically, with a peak around
. We perform additional simulations with a single probe molecule (
) in a linear matrix (
). The non‐monotonicity in Dr persists even after ring–ring interactions are eliminated. Topology dependent differences in the short‐time dynamics of the probes are observed; unlike linear probes, mean‐squared displacements of ring probes depend on Nm. Primitive path analysis suggests that the difference in dynamics originates from differences in entanglement structure. For linear probes, the degree of entanglement is independent of Nm. For ring probes, we observe two regimes: when Nm is small, the number of threadings decreases as Nm increases, eventually transitioning to a plateau. In the small Nm regime, the change in the degree of entanglement offsets the change in the mobility of the matrix chains, leading to a non‐monotonic variation in Dr. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 169–177
Respiratory syncytial virus hospitalization and mortality: Systematic review and meta‐analysis
Authors: Stein Renato T. , Bont Louis J. , Zar Heather , Polack Fernando P. , Park Caroline , Claxton Ami , Borok Gerald , Butylkova Yekaterina , Wegzyn Colleen 
Published: October 2016

SummaryBackground: Respiratory syncytial virus (RSV) is a major public health burden worldwide. We aimed to review the current literature on the incidence and mortality of severe RSV in children globally. Methods: Systematic literature review and meta‐analysis of published data from 2000 onwards, reporting on burden of acute respiratory infection (ARI) due to RSV in children. Main outcomes were hospitalization for severe RSV‐ARI and death. Results: Five thousand two hundred and seventy‐four references were identified. Fifty‐five studies were included from 32 countries. The global RSV‐ARI hospitalization estimates, reported per 1,000 children per year (95% Credible Interval (CrI), were 4.37 (2.98, 6.42) among children <5 years, 19.19 (15.04, 24.48) among children <1 year, 20.01 (9.65, 41.31) among children <6 months and 63.85 (37.52, 109.70) among premature children <1 year. The RSV‐ARI global case‐fatality estimates, reported per 1,000 children, (95% Crl) were 6.21 (2.64, 13.73) among children <5 years, 6.60 (1.85, 16.93) for children <1 year, and 1.04 (0.17, 12.06) among preterm children <1 year. Conclusions: A substantial proportion of RSV‐associated morbidity occurs in the first year of life, especially in children born prematurely. These data affirm the importance of RSV disease in the causation of hospitalization and as a significant contributor to pediatric mortality and further demonstrate gestational age as a critical determinant of disease severity. An important limitation of case‐fatality ratios is the absence of individual patient characteristics of non‐surviving patients. Moreover, case‐fatality ratios cannot be translated to population‐based mortality. Pediatr Pulmonol. 2017;52:556–569. © 2016 The Authors. Pediatric Pulmonology. Published by Wiley Periodicals, Inc.