bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Small‐Molecule Protein–Protein Interaction Inhibitor of PARP1 That Targets Its BRCT Domain
Authors: Na Zhenkun , Peng Bo , Ng Shukie , Pan Sijun , Lee Jun‐Seok , Shen Han‐Ming , Yao Shao Q. 
Published: January 2015

AbstractPoly(ADP‐ribose)polymerase‐1 (PARP1) is a BRCT‐containing enzyme (BRCT=BRCA1 C‐terminus) mainly involved in DNA repair and damage response and a validated target for cancer treatment. Small‐molecule inhibitors that target the PARP1 catalytic domain have been actively pursued as anticancer drugs, but are potentially problematic owing to a lack of selectivity. Compounds that are capable of disrupting protein–protein interactions of PARP1 provide an alternative by inhibiting its activities with improved selectivity profiles. Herein, by establishing a high‐throughput microplate‐based assay suitable for screening potential PPI inhibitors of the PARP1 BRCT domain, we have discovered that (±)‐gossypol, a natural product with a number of known biological activities, possesses novel PARP1 inhibitory activity both in vitro and in cancer cells and presumably acts through disruption of protein–protein interactions. As the first known cell‐permeable small‐molecule PPI inhibitor of PAPR1, we further established that (−)‐gossypol was likely the causative agent of PARP1 inhibition by promoting the formation of a 1:2 compound/PARP1 complex by reversible formation of a covalent imine linkage.
Formation of silk fibroin hydrogel and evaluation of its drug release profile
Authors: de Moraes Mariana Agostini , Albrecht Mahl Cynthia Regina , Ferreira Silva Mariana , Beppu Marisa Masumi 
Published: January 2015

ABSTRACTSilk hydrogels are interesting materials to be used as matrix in controlled drug delivery devices. However, methods to accelerate fibroin gelation and allow the drug incorporation during the hydrogel preparation are needed in literature. In this article we report the preparation of silk fibroin hydrogels with addition of several contents of ethanol, used to accelerate fibroin gelation kinetics, and we also evaluate the potential of these hydrogels to be used as matrices for drug delivery. Chemical and conformational properties did not change despite the amount of ethanol incorporated in the hydrogel. Hydrogels containing diclofenac sodium dissolved in ethanol showed a faster initial release of the drug than hydrogels with the drug dissolved in water but equilibrium was reached later. This indicates a more sustained drug delivery from hydrogels in which the model drug was dissolved in ethanol. Fibroin hydrogels confirm their promising use as biopolymeric matrices for controlled drug release. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41802.
Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) films for food packaging: Physical–chemical and structural stability under food contact conditions
Authors: Chea Vorleak , Angellier‐Coussy Hélène , Peyron Stéphane , Kemmer Diana , Gontard Nathalie 
Published: January 2015

ABSTRACTThe objective of the present article is to bring new insights into the relationships between the structural and physical–chemical stability and the inertness of PHBV films with respect to the targeted food packaging application. It is concluded from overall migration tests that PHBV films can be used as food contact materials for any type of food. Functional properties of PHBV films (mechanical properties and water vapor permeability) were also very stable after contact at 40°C during 10 days with all food simulating liquids tested (water, acetic acid 3% (w/v), ethanol 20% (v/v), and iso‐octane), except with ethanol 95% (v/v). Ethanol 95% (v/v) was identified as the worst case for PHBV films, with a high sorption value and an increase in the water vapor permeability. This was mainly explained by a significant plasticizing effect, together with a decrease in both the molecular weight and the crystallinity degree of PHBV films. From an industrial point of view, it allows assessing that the packaging functions of PHBV are fulfilled all over the food supply chain. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 41850.
Fiber preparation and mechanical properties of recycled polypropylene for reinforcing concrete
Authors: Yin Shi , Tuladhar Rabin , Shanks Robert A. , Collister Tony , Combe Mark , Jacob Mohan , Tian Ming , Sivakugan Nagaratnam 
Published: January 2015

ABSTRACTPolypropylene (PP) fibers have been widely used to reinforce concrete footpaths as an alternative to steel mesh. The reinforcing effect of the PP fiber is directly proportional to its tensile strength and Young modulus. This research explored the feasibility of using an improved melt spinning and hot drawing process to produce virgin and recycled PP fibers of high mechanical properties in an industrial scale. Commercial grade granules of virgin PP, recycled PP and HPDE were mixed in different proportions in preparing five different types of fibers. All the fibers obtained high tensile strength and Young modulus. A relationship between the structural parameters and mechanical properties was then established. It was observed that the melt spinning and hot drawing process formed both α‐form and β‐form crystals in the PP fibers, and significantly improved crystallinity from about 50% to 80%. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41866.
Biodegradable high oxygen barrier membrane for chilled meat packaging
Authors: Dong Tungalag , Yun Xueyan , Li Mengting , Sun Wenxiu , Duan Yan , Jin Ye 
Published: January 2015

ABSTRACT“Chilled” meat is more nutritional, healthy and hygienic than the meat kept at ambient temperature. “Poly(propylene carbonate) (PPC) and poly(vinly alcohol) (PVA) were used to prepare biodegradable three‐layer PPC/PVA/PPC films with high barrier and tensile properties. The potential benefits of the developed films were also evaluated on the shelf life of chilled meat products. Compared to PPC film, using 20 wt % PVA as an intermediate layer in PPC/PVA/PPC film remarkably enhanced oxygen barrier performance at 0 and 50 RH % by about 500 times, tensile strength by about 8 times, and Young's modulus by nine times, but no beneficial effect on water vapor barrier performance has been observed. A new “sandwich” type of completely biodegradable material with high barrier was obtained. The application of PPC/PVA20/PPC film as the packaging material of chilled meat was effectively kept the total viable count (TVC) and total volatile basic nitrogen (TVB‐N) to acceptable levels in chilled meats until 19th day of storage at 4°C, however, the spoilage occurred within 11th and 14th days of refrigerated storage in term of TVC and TVB‐N, respectively, in the chilled meats packed with only PPC. Herein, we report that PPC/PVA/PPC three‐layer film can be a promising well‐defined biodegradable material with excellent potential in chilled meat packaging. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41871.
Thermal and mechanical properties of multiple‐component aliphatic degradable polyurethanes
Authors: Poręba Rafał , Kredatusová Jana , Hodan Jiří , Serkis Magdalena , Špírková Milena 
Published: January 2015

ABSTRACTMacroscopic thermal and mechanical properties of complex aliphatic polycarbonate‐based polyurethane (PU) films containing degradable ester units in PU backbone were studied by a combination of several experimental techniques. Differential scanning calorimetry (DSC) revealed that the synthesized oligomeric diol (DL‐L) contributes (in addition to polycarbonate diol) to the formation of soft‐segment domains, while the hard‐segment domains are formed from 1,6‐diisocyanatohexane (HDI) and butane‐1,4‐diol (BD). Three main phase transitions were detected by DSC and by dynamic mechanical thermal analysis. Thermogravimetric analysis (TGA) of two‐component PUs showed that the PU made from DL‐L and HDI is the least thermostable product, while the PU made from polycarbonate diol and HDI is the most stable one. The differences in the thermal stability of different four‐component PUs are not important. Tensile properties very sensitively reflect the changes in composition and in microstructure of PU samples; the best tensile properties exhibits the degradable sample containing the equimolar ratio of hydroxyl groups of macrodiol, oligomeric diol DL‐L and butane‐1,4‐diol. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41872.
Injury and Subsequent Regeneration of Muscles for Activation of Local Innate Immunity to Facilitate the Development and Relapse of Autoimmune Myositis in C57BL/6 Mice
Authors: Kimura Naoki , Hirata Shinya , Miyasaka Nobuyuki , Kawahata Kimito , Kohsaka Hitoshi 
Published: January 2015

ObjectiveTo determine whether injury and regeneration of the skeletal muscles induce an inflammatory milieu that facilitates the development and relapse of autoimmune myositis.MethodsThe quadriceps of C57BL/6 mice were injured with bupivacaine hydrochloride (BPVC) and evaluated histologically. Macrophages and regenerating myofibers in the treated muscles and differentiating C2C12 myotubes were examined for cytokine expression. Mice were immunized with C protein fragments at the base of the tail and in the right hind footpads (day 0) to evoke systemic anti–C protein immunity and to induce local myositis in the right hind limbs. The contralateral quadriceps muscles were injured with BPVC or phosphate buffered saline (PBS) on day 7 or after spontaneous regression of myositis (day 42). The quadriceps muscle in nonimmunized mice was injured with BPVC on day 7. The muscles were examined histologically 14 days after treatment.ResultsThe BPVC‐injured muscles had macrophage infiltration most abundantly at 3 days after the injection, with emergence of regenerating fibers from day 5. The macrophages expressed inflammatory cytokines, including tumor necrosis factor α, interleukin‐1β, and CCL2. Regenerating myofibers and C2C12 myotubes also expressed the cytokines. The BPVC‐injected muscles from nonimmunized mice had regenerating myofibers with resolved cell infiltration 14 days after treatment. In mice preimmunized with C protein fragments, the muscles injected with BPVC on day 7 as well as on day 42, but not those injected with PBS, had myositis accompanied by CD8+ T cell infiltration.ConclusionInjury and regeneration could set up an inflammatory milieu in the muscles and facilitate the development and relapse of autoimmune myositis.
Circulating Follicular Helper–Like T Cells in Systemic Lupus Erythematosus: Association With Disease Activity
Authors: Choi Jin‐Young , Ho John Hsi‐en , Pasoto Sandra G. , Bunin Viviane , Kim Sang Taek , Carrasco Solange , Borba Eduardo F. , Gonçalves Celio R. , Costa Priscila R. , Kallas Esper G. , Bonfa Eloisa , Craft Joseph 
Published: January 2015

ObjectiveTo assess circulating follicular helper T (Tfh)–like CD4+ T cells in patients with systemic lupus erythematosus (SLE) and determine their relationship to disease activity.MethodsBlood samples from patients with SLE, as well as blood samples from patients with Behçet's disease (BD) and healthy individuals as controls, were analyzed. In all samples, circulating Tfh‐like cells were enumerated by flow cytometry, using, as markers, expression of CXCR5, inducible T cell costimulator (ICOS), and programmed death 1 (PD‐1) protein, as well as secretion of interleukin‐21 (IL‐21). The frequency of circulating Tfh‐like cells was compared to that of circulating plasmablasts (CD19+IgD−CD38+). In addition, the possible association of circulating Tfh‐like cells with the SLE Disease Activity Index (SLEDAI) was evaluated.ResultsThe subset of circulating Tfh‐like T cells, identified as CXCR5highICOShighPD‐1high, was expanded in the blood of SLE patients compared to controls. Circulating Tfh‐like cells were found to produce IL‐21 and had lower expression of CCR7 as compared to that in circulating CXCR5high central memory T cells, thereby enabling their distinction. Expression of PD‐1, but not ICOS or CXCR5, was significantly elevated in circulating Tfh‐like cells from SLE patients compared to controls. PD‐1 expression among CXCR5high circulating Tfh‐like cells correlated with the SLEDAI, frequency of circulating plasmablasts, and anti–double‐stranded DNA antibody positivity, but not with disease duration or past organ injury; rather, this cell profile appeared to be a reflection of current active disease.ConclusionCirculating Tfh‐like cells are associated with disease activity in SLE, suggesting that their presence indicates abnormal homeostasis of T cell–B cell collaboration, with a causal relationship that is central to disease pathogenesis. These findings also suggest that circulating Tfh‐like cells provide a surrogate for aberrant germinal center activity in SLE, and that their PD‐1 expression offers a tool for measuring disease activity and monitoring the response to therapies.
Survival of Adults With Systemic Sclerosis Following Lung Transplantation: A Nationwide Cohort Study
Authors: Bernstein Elana J. , Peterson Eric R. , Sell Jessica L. , D'Ovidio Frank , Arcasoy Selim M. , Bathon Joan M. , Lederer David J. 
Published: January 2015

ObjectiveMany transplant programs are hesitant to offer lung transplantation to patients with systemic sclerosis (SSc) due to concerns about extrapulmonary involvement that might affect survival. The aim of this study was to determine whether adults with SSc have higher 1‐year mortality rates after lung transplantation compared to those with interstitial lung disease (ILD) or pulmonary arterial hypertension (PAH) not due to SSc.MethodsUsing data provided by the United Network for Organ Sharing, we performed a retrospective cohort study of 229 adults with SSc, 201 with PAH, and 3,333 with ILD who underwent lung transplantation in the US between May 4, 2005 and September 14, 2012. We examined associations between diagnosis and 1‐year survival after lung transplantation using stratified Cox models adjusted for recipient, donor, and procedure factors.ResultsAdults with SSc undergoing lung transplantation in the US had a multivariable‐adjusted 48% relative increase in the 1‐year mortality rate compared to those with non–SSc‐related ILD (hazard ratio 1.48 [95% confidence interval 1.01–2.17]). However, we did not detect a difference in the risk of death at 1 year between those with SSc and those with non–SSc‐related PAH (hazard ratio 0.85 [95% confidence interval 0.50–1.44]).ConclusionA diagnosis of SSc may confer an increased risk of death 1 year following lung transplantation compared to a diagnosis of ILD, but this risk is similar to that of PAH, a widely accepted indication for lung transplantation. Future work should identify modifiable risk factors that can improve transplant outcomes in this population.
Transition‐Metal‐Catalyzed π‐Bond‐Assisted CH Bond Functionalization: An Emerging Trend in Organic Synthesis
Authors: Gandeepan Parthasarathy , Cheng Chien‐Hong 
Published: January 2015

AbstractTransition‐metal‐catalyzed CH activation is considered to be an important tool in organic synthesis and has been accepted and widely used by chemists because it is straightforward, cost‐effective, and environmentally friendly. A variety of functional groups have been used to direct metal complexes and achieve regioselective CH activation. Most directing is achieved through the σ‐bond coordination of functional groups to the metal catalyst, followed by ortho‐selective CH bond cleavage. However, recent work has demonstrated that π‐coordinating functional groups can also assist in guiding metal complexes for site‐selective CH bond activation. This emerging approach significantly expands the scope of CH activation reactions in organic synthesis. Herein, recent developments in this field are summarized.
TPτ Model Transformation: A Systematic Modelling Framework to Handle Internal Time Delays in Control Systems
Authors: Galambos Péter , Baranyi Péter 
Published: January 2015

AbstractVarying time delays are inherent and unavoidable properties of a large set of control systems causing stability issues in most cases. Control design methods that guarantee the stability, such as those based on the Lyapunov–Krasovskii functional, are mathematically highly complicated and therefore have hardly spread into everyday engineering practice. This paper introduces a systematic modelling and control design schema enabling a gateway between the different delayed system representations and the tensor product (TP) type convex polytopic models which allows the direct use of linear matrix inequality (LMI)‐based controller and observer synthesis. The approach presented assumes known, bounded, time‐varying internal time‐delays where the delay derivative is not considered. The proposed modelling scheme is demonstrated via a numerical example.
Expanding the substrate scope of chitooligosaccharide oxidase from Fusarium graminearum by structure‐inspired mutagenesis
Authors: Ferrari Alessandro R. , Lee Misun , Fraaije Marco W. 
Published: January 2015

ABSTRACTChitooligosaccharide oxidase from Fusarium graminearum (ChitO) oxidizes N‐acetyl‐D‐glucosamine (GlcNAc) and its oligomers with high efficiency at the C1‐hydroxyl moiety while it shows poor or no activity with other carbohydrates. By sequence and structural comparison with other known carbohydrate oxidases (glucooligosaccharide oxidase from Acremonium strictum and lactose oxidase from Microdochium nivale) eleven mutants were designed to redirect the catalytic scope of ChitO for improved oxidation of lactose, cellobiose and maltose. The catalytic properties of the most interesting mutants were further improved by combining single mutations. This has resulted in the creation of a set of ChitO variants that display totally different substrate tolerances. One ChitO variant shows a dramatic improvement in catalytic efficiency towards oxidation of glucose, cellobiose, lactose, and maltose. We also describe a ChitO variant with the highest catalytic efficiency in GlcNAc oxidation so far reported in the literature. Biotechnol. Bioeng. 2015;112: 1074–1080. © 2015 Wiley Periodicals, Inc.
Engineering a thermostable fungal GH10 xylanase, importance of N‐terminal amino acids
Authors: Song Letian , Tsang Adrian , Sylvestre Michel 
Published: January 2015

ABSTRACTXylanases are used in many industrial processes including pulp bleaching, baking, detergent, and the hydrolysis of plant cell wall in biofuels production. In this work we have evolved a single domain GH10 xylanase, Xyn10A_ASPNG, from Aspergillus niger to improve its thermostability. We introduced a rational approach involving as the first step a computational analysis to guide the design of a mutagenesis library in targeted regions which identified thermal important residues that were subsequently randomly mutagenized through rounds of iterative saturation mutagenesis (ISM). Focusing on five residues, four rounds of ISM had generated a quintuple mutant 4S1 (R25W/V29A/I31L/L43F/T58I) which exhibited thermal inactivation half‐life (t1/2) at 60°C that was prolonged by 30 folds in comparison with wild‐type enzyme. Whereas the wild‐type enzyme retained 0.2% of its initial activity after a heat treatment of 10 min at 60°C and was completely inactivated after 2 min at 65°C, 4S1 mutant retained 30% of its initial activity after 15 min heating at 65°C. Furthermore, the mutant melting temperature (Tm) increased by 17.4°C compared to the wild type. Each of the five mutations in 4S1 was found to contribute to thermoresistance, but the dramatic improvement of enzyme thermoresistance of 4S1 was attributed to the synergistic effects of the five mutations. Comparison of biochemical data and model structure between 4S1 and the wild‐type enzyme suggested that the N‐terminal coil of the enzyme is important in stabilizing GH10 xylanase structure. Based on model structure analyses, we propose that enforced hydrophobic interactions within N‐terminal elements and between N‐ and C‐terminal ends are responsible for the improved thermostability of Xyn10A_ASPNG. Biotechnol. Bioeng. 2015;112: 1081–1091. © 2015 Wiley Periodicals, Inc.
Hybrids of Copolymers of Fluorene and C60‐Carrying‐Carbazole with Semiconducting Single‐Walled Carbon Nanotubes
Authors: Toshimitsu Fumiyuki , Ozawa Hiroaki , Nakashima Naotoshi 
Published: January 2015

AbstractThree different copolymers of C60‐carrying‐carbazole and fluorene units with different copolymer composition ratios were designed and synthesized. On the basis of photoluminescence, atomic force microscopy, and Vis‐NIR and Raman spectroscopic analysis, we found that these copolymers solubilize only semiconducting single‐walled carbon nanotubes (sem‐SWNTs) to form copolymer/sem‐SWNT hybrids, in which energy transfer from the copolymer/C60 moieties to the SWNTs was revealed. By comparing two possible hybrid structures with molecular‐mechanics simulations, the greatest stabilization was found when the C60 moieties lay on the sem‐SWNT surfaces.
Expedient Synthesis of C‐Aryl Carbohydrates by Consecutive Biocatalytic Benzoin and Aldol Reactions
Authors: Hernández Karel , Parella Teodor , Joglar Jesús , Bujons Jordi , Pohl Martina , Clapés Pere 
Published: January 2015

AbstractThe introduction of aromatic residues connected by a CC bond into the non‐reducing end of carbohydrates is highly significant for the development of innovative structures with improved binding affinity and selectivity (e.g., Caril‐sLex). In this work, an expedient asymmetric “de novo” synthetic route to new aryl carbohydrate derivatives based on two sequential stereoselectively biocatalytic carboligation reactions is presented. First, the benzoin reaction of aromatic aldehydes to dimethoxyacetaldehyde is conducted, catalyzed by benzaldehyde lyase from Pseudomonas fluorescens biovar I. Then, the α‐hydroxyketones formed are reduced by using NaBH4 yielding the anti diol. After acetal hydrolysis, the aldol addition of dihydroxyacetone, hydroxyacetone, or glycolaldehyde catalyzed by the stereocomplementary D‐fructose‐6‐phosphate aldolase and L‐rhamnulose‐1‐phosphate aldolase is performed. Both aldolases accept unphosphorylated donor substrates, avoiding the need of handling the phosphate group that the dihydroxyacetone phosphate‐dependent aldolases require. In this way, 6‐C‐aryl‐L‐sorbose, 6‐C‐aryl–L‐fructose, 6‐C‐aryl–L‐tagatose, and 5‐C‐aryl‐L‐xylose derivatives are prepared by using this methodology.
Poren nach Maß – Struktur‐Eigenschafts‐Beziehungen unter der chemiedidaktischen Lupe
Authors: Herzog Stefanie , Finlayson Odilla , Hickmann Katharina , Parchmann Ilka 
Published: January 2015

AbstractEin Verständnis von Struktur‐Eigenschafts‐Beziehungen ist relevant, wenn beobachtbare Eigenschaften auf Grundlage mikroskopischer Strukturen unter Einbeziehung verschiedener Modelle erklärt oder vorhergesagt werden sollen. Dabei ist es vor allem entscheidend, neben den einzelnen Atomen und funktionellen Gruppen auch auf das „große Ganze“ submikroskopischer Strukturen zu schauen, da häufig erst die vorhandenen Zwischenräume in Makromolekülen deren makroskopische Eigenschaften bedingen. Im vorliegenden Beitrag werden solche Wechselwirkungen zwischen Modellen und Eigenschaften auf verschiedenen Ebenen entlang eines forschend‐entwickelnden Unterrichtsgangs zum Thema „Poren nach Maß“ dargelegt und ausgewählte Aspekte einer Umsetzung für die Sekundarstufe I präsentiert. Die verschiedenen Niveaustufen bieten Zugänge für Lernende aller Altersklassen, und es werden neben den geforderten Methoden zur Erkenntnisgewinnung auch verfahrenstechnische bzw. industrielle Fragen zur Produktoptimierung aufgeworfen, denen die Lernenden nachgehen können.