bluuebunny/crossref_metadata_2025_split huggingface dataset:
Topical cathelicidin (LL‐37) an innate immune peptide induces acute olfactory epithelium inflammation in a mouse model
Authors: Alt Jeremiah A. , Qin Xuan , Pulsipher Abigail , Orb Quinn , Orlandi Richard R. , Zhang Jianxing , Schults Austin , Jia Wanjian , Presson Angela P. , Prestwich Glenn D. , Oottamasathien Siam 
Published: September 2015

BackgroundCathelicidin (LL‐37) is an endogenous innate immune peptide that is elevated in patients with chronic rhinosinusitis (CRS). The role of LL‐37 in olfactory epithelium (OE) inflammation remains unknown. We hypothesized that: (1) LL‐37 topically delivered would elicit profound OE inflammation; and (2) LL‐37 induced inflammation is associated with increased infiltration of neutrophils and mast cells.MethodsTo test our hypothesis we challenged C57BL/6 mice intranasally with increasing concentrations of LL‐37. At 24 hours tissues were examined histologically and scored for inflammatory cell infiltrate, edema, and secretory hyperplasia. In separate experiments, fluorescently conjugated LL‐37 was instilled and tissues were examined at 0.5 and 24 hours. To test our last hypothesis, we performed tissue myeloperoxidase (MPO) assays for neutrophil activity and immunohistochemistry for tryptase to determine the mean number of mast cells per mm2.ResultsLL‐37 caused increased inflammatory cell infiltrate, edema, and secretory cell hyperplasia of the sinonasal mucosa, with higher LL‐37 concentrations yielding significantly more inflammatory changes (p < 0.01). Fluorescent LL‐37 demonstrated global sinonasal epithelial binding and tissue distribution. Further, higher concentrations of LL‐37 led to significantly greater MPO levels with dose‐dependent increases in mast cell infiltration (p < 0.01).ConclusionLL‐37 has dramatic inflammatory effects in the OE mucosa that is dose‐dependent. The observed inflammatory changes in the olfactory mucosa were associated with the infiltration of both neutrophils and mast cells. Our biologic model represents a new model to further investigate the role of LL‐37 in OE inflammation.
A Zinc(II) Photocage Based on a Decarboxylation Metal Ion Release Mechanism for Investigating Homeostasis and Biological Signaling
Authors: Basa Prem N. , Antala Sagar , Dempski Robert E. , Burdette Shawn C. 
Published: September 2015

AbstractMetal ion signaling in biology has been studied extensively with ortho‐nitrobenzyl photocages; however, the low quantum yields and other optical properties are not ideal for these applications. We describe the synthesis and characterization of NTAdeCage, the first member in a new class of Zn2+ photocages that utilizes a light‐driven decarboxylation reaction in the metal ion release mechanism. NTAdeCage binds Zn2+ with sub‐pM affinity using a modified nitrilotriacetate chelator and exhibits an almost 6 order of magnitude decrease in metal binding affinity upon uncaging. In contrast to other metal ion photocages, NTAdeCage and the corresponding Zn2+ complex undergo efficient photolysis with quantum yields approaching 30 %. The ability of NTAdeCage to mediate the uptake of 65Zn2+ by Xenopus laevis oocytes expressing hZIP4 demonstrates the viability of this photocaging strategy to execute biological assays.
Chiral Primary Amine/Palladium Dual Catalysis for Asymmetric Allylic Alkylation of β‐Ketocarbonyl Compounds with Allylic Alcohols
Authors: Zhou Han , Zhang Long , Xu Changming , Luo Sanzhong 
Published: September 2015

AbstractAn efficient dual catalytic system composed of a chiral primary amine and a palladium complex was developed to promote the direct asymmetric allylic alkylation (AAA) of β‐ketocarbonyl compounds. In particular, the synergistic dual catalytic system enabled the AAA reaction of challenging acyclic aliphatic ketones, such as β‐ketocarbonyl compounds and 1,3‐diketones.
Protein Electronic Conductors: Hemin–Substrate Bonding Dictates Transport Mechanism and Efficiency across Myoglobin
Authors: Raichlin Sara , Pecht Israel , Sheves Mordechai , Cahen David 
Published: September 2015

AbstractElectron transport (ETp) across met‐myoglobin (m‐Mb), as measured in a solid‐state‐like configuration between two electronic contacts, increases by up to 20 fold if Mb is covalently bound to one of the contacts, a Si electrode, in an oriented manner by its hemin (ferric) group, rather than in a non‐oriented manner. Oriented binding of Mb is achieved by covalently binding hemin molecules to form a monolayer on the Si electrode, followed by reconstitution with apo‐Mb. We found that the ETp temperature dependence (>120 K) of non‐oriented m‐Mb virtually disappears when bound in an oriented manner by the hemin group. Our results highlight that combining direct chemical coupling of the protein to one of the electrodes with uniform protein orientation strongly improves the efficiency of ET across the protein. We hypothesize that the behavior of reconstituted m‐Mb is due to both strong protein–substrate electronic coupling (which is likely greater than in non‐oriented m‐Mb) and direct access to a highly efficient transport path provided by the hemin group in this configuration.
Radical Formation in the Gas‐Phase Ozonolysis of Deprotonated Cysteine
Authors: Khairallah George N. , Maccarone Alan T. , Pham Huong T. , Benton Timothy M. , Ly Tony , da Silva Gabriel , Blanksby Stephen J. , O'Hair Richard A. J. 
Published: September 2015

AbstractAlthough the deleterious effects of ozone on the human respiratory system are well‐known, many of the precise chemical mechanisms that both cause damage and afford protection in the pulmonary epithelial lining fluid are poorly understood. As a key first step to elucidating the intrinsic reactivity of ozone with proteins, its reactions with deprotonated cysteine [Cys−H]− are examined in the gas phase. Reaction proceeds at near the collision limit to give a rich set of products including 1) sequential oxygen atom abstraction reactions to yield cysteine sulfenate, sulfinate and sulfonate anions, and significantly 2) sulfenate radical anions formed by ejection of a hydroperoxy radical. The free‐radical pathway occurs only when both thiol and carboxylate moieties are available, implicating electron‐transfer as a key step in this reaction. This novel and facile reaction is also observed in small cys‐containing peptides indicating a possible role for this chemistry in protein ozonolysis.
Herstellung mikrostrukturierter Polymerbürsten auf wiederbeschreibbaren Oberflächen durch Triazolindion‐Click‐Chemie
Authors: Roling Oliver , De Bruycker Kevin , Vonhören Benjamin , Stricker Lucas , Körsgen Martin , Arlinghaus Heinrich F. , Ravoo Bart Jan , Du Prez Filip E. 
Published: September 2015

AbstractTriazolindion‐Click‐Chemie und Mikrokontaktchemie wurden kombiniert, um Polymerbürsten auf Oberflächen zu drucken, zu löschen und anschließend erneut anzubinden. Die mikrostrukturierten Polymerbürsten wurden auf Alken‐ und Indol‐Monoschichten gebildet, indem zuerst ein mit Triazolindion (TAD) substituierter Atomtransferradikalpolymerisationinitiator (ATRP‐TAD) auf die Monoschichten gedruckt und anschließend eine oberflächeninitiierte Polymerisation durchgeführt wurde. Der dynamische Charakter des Alder‐En‐Addukts von TAD und Indol erlaubte es, die Polymerbürsten bei erhöhten Temperaturen von der Oberfläche zu löschen, während die regenerierten Indol‐Monoschichten neu strukturiert wurden. Der Zyklus aus Schreiben und Löschen konnte vier Mal durchlaufen werden, wodurch die Robustheit der Methode bewiesen ist.
Biomimetische [2Fe‐2S]‐Cluster mit stark delokalisierten gemischtvalenten Eisenzentren
Authors: Yao Shenglai , Meier Florian , Lindenmaier Nils , Rudolph Robert , Blom Burgert , Adelhardt Mario , Sutter Jörg , Mebs Stefan , Haumann Michael , Meyer Karsten , Kaupp Martin , Driess Matthias 
Published: September 2015

AbstractEine vollständige Serie von biomimetischen [2Fe‐2S]‐Clustern [(LDepFe)2(μ‐S)2] (3, LDep=CH[CMeN(2,6‐Et2C6H3)]2), [(LDepFe)2(μ‐S)2K] (4), [(LDepFe)2(μ‐S)2][Bu4N] (5, Bu=n‐butyl) und [(LDepFe)2(μ‐S)2K2] (6) wurde hergestellt und charakterisiert. Das homovalente [2Fe(3+/3+)‐2S]‐Cluster 3 ist durch die Reaktion von [(LDepFe)2(μ‐H)2] 2 mit elementarem Schwefel zugänglich. Die chemische Reduktion von 3 mit einem Moläquivalent elementaren Kalium ergibt das Kontaktionenpaar K+[2Fe‐2S]− (4) in Form eines eindimensionalen Koordinationspolymers, das sich wiederum mit [Bu4N]Cl zum separierten Ionenpaar [Bu4N]+[2Fe‐2S]− (5) umsetzen lässt. Weitere Reduktion von 4 mit Kalium erlaubt den Zugang zum superreduzierten homovalenten [2Fe(2+/2+)‐2S]‐Cluster 6. Bemerkenswert hierbei ist, dass es sich bei den Komplexen 4 und 5 um [2Fe‐2S]‐Cluster mit einem jeweils stark delokalisierten Fe2+Fe3+‐Paar handelt, was durch 57Fe‐Mößbauer‐, Röntgenabsorptions‐ und Röntgenemissionsspektroskopie (XAS, XES) in Übereinstimmung mit DFT‐Rechnungen gesichert ist.
Stepwise Reduction of 9,10‐Bis(dimesitylboryl)anthracene
Authors: Zheng Yang , Xiong Jiao , Sun Yangyang , Pan Xiaobo , Wu Jincai 
Published: September 2015

AbstractStepwise reduction of 9,10‐bis(dimesitylboryl)anthracene afforded an radical anion and a dianion, accompanied by stepwise changes of the aromaticity of the anthracene moiety. The radical has a planar semiquinoidal structure, while the dianion has a puckered quinoidal structure. The alteration of the geometries of the 9,10‐bis(dimesitylboryl)anthracene upon reduction is rationalized by the nature of the bonding. These results have been confirmed by cyclic voltammetry, X‐ray crystallography, NMR, EPR, and UV‐vis‐NIR spectroscopy, as well as DFT calculations.
Rewritable Polymer Brush Micropatterns Grafted by Triazolinedione Click Chemistry
Authors: Roling Oliver , De Bruycker Kevin , Vonhören Benjamin , Stricker Lucas , Körsgen Martin , Arlinghaus Heinrich F. , Ravoo Bart Jan , Du Prez Filip E. 
Published: September 2015

AbstractTriazolinedione (TAD) click reactions were combined with microcontact chemistry to print, erase, and reprint polymer brushes on surfaces. By patterning substrates with a TAD‐tagged atom‐transfer radical polymerization initiator (ATRP‐TAD) and subsequent surface initiated ATRP, it was possible to graft micropatterned polymer brushes from both alkene‐ and indole‐functionalized substrates. As a result of the dynamic nature of the Alder–ene adduct of TAD and indole at elevated temperatures, the polymer pattern could be erased while the regenerated indole substrate could be reused to print new patterns. To demonstrate the robustness of the methodology, the write–erase cycle was repeated four times.
Biomimetic [2Fe‐2S] Clusters with Extensively Delocalized Mixed‐Valence Iron Centers
Authors: Yao Shenglai , Meier Florian , Lindenmaier Nils , Rudolph Robert , Blom Burgert , Adelhardt Mario , Sutter Jörg , Mebs Stefan , Haumann Michael , Meyer Karsten , Kaupp Martin , Driess Matthias 
Published: September 2015

AbstractA complete series of biomimetic [2Fe‐2S] clusters, [(LDepFe)2(μ‐S)2] (3, LDep=CH[CMeN(2,6‐Et2C6H3)]2), [(LDepFe)2(μ‐S)2K] (4), [(LDepFe)2(μ‐S)2][Bu4N] (5, Bu=n‐butyl), and [(LDepFe)2(μ‐S)2K2] (6), could be synthesized and characterized. The all‐ferric [2Fe‐2S] cluster 3 is readily accessible through the reaction of [(LDepFe)2(μ‐H)2] (2) with elemental sulfur. The chemical reduction of 3 with one molar equivalent of elemental potassium affords the contact ion pair K+[2Fe‐2S]− (4) as a one‐dimensional coordination polymer, which in turn reacts with [Bu4N]Cl to afford the separate ion pair [Bu4N]+[2Fe‐2S]− (5). Further reduction of 4 with potassium furnishes the super‐reduced all‐ferrous [2Fe‐2S] cluster 6. Remarkably, complexes 4 and 5 are [2Fe‐2S] clusters with extensively delocalized Fe2+Fe3+ pairs as evidenced by 57Fe Mössbauer, X‐ray absorption and emission spectroscopy (XAS, XES) and in accordance with DFT calculations.
Potato peeling costreams as raw materials for biopolymer film preparation
Authors: Rommi Katariina , Rahikainen Jenni , Vartiainen Jari , Holopainen Ulla , Lahtinen Panu , Honkapää Kaisu , Lantto Raija 
Published: September 2015

ABSTRACTPotato peel mass is a costream produced in large quantities by the food industry. Its availability and the presence of starch (46%), pectin, and cellulose make it a potential renewable raw material for polymer products. In this study, biopolymer films were produced from potato peel mass and glycerol. High‐pressure homogenization (HPH) and HPH combined with heat treatment were investigated as pretreatment technologies before film casting. HPH‐treated potato peel mass yielded biopolymer films with similar barrier and mechanical properties as films prepared from pure potato starch, including complete impermeability to grease. Additional heat treatment of the peel mass enhanced starch gelatinization, resulting in improved barrier properties and smoother surface topography of the films. Films with similar appearance and quality were also obtained from starch‐free potato peel mass, indicating that potato fiber rich in pectin and cellulose is likewise a suitable material for biopolymer film preparation after HPH treatment. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42862.
Similar substrate specificity of cynomolgus monkey cytochrome P450 2C19 to reported human P450 2C counterpart enzymes by evaluation of 89 drug clearances
Authors: Hosaka Shinya , Murayama Norie , Satsukawa Masahiro , Uehara Shotaro , Shimizu Makiko , Iwasaki Kazuhide , Iwano Shunsuke , Uno Yasuhiro , Yamazaki Hiroshi 
Published: September 2015

ABSTRACTCynomolgus monkeys are used widely in preclinical studies as non‐human primate species. The amino acid sequence of cynomolgus monkey cytochrome P450 (P450 or CYP) 2C19 is reportedly highly correlated to that of human CYP2C19 (92%) and CYP2C9 (93%). In the present study, 89 commercially available compounds were screened to find potential substrates for cynomolgus monkey CYP2C19. Of 89 drugs, 34 were metabolically depleted by cynomolgus monkey CYP2C19 with relatively high rates. Among them, 30 compounds have been reported as substrates or inhibitors of, either or both, human CYP2C19 and CYP2C9. Several compounds, including loratadine, showed high selectivity to cynomolgus monkey CYP2C19, and all of these have been reported as human CYP2C19 and/or CYP2C9 substrates. In addition, cynomolgus monkey CYP2C19 formed the same loratadine metabolite as human CYP2C19, descarboethoxyloratadine. These results suggest that cynomolgus monkey CYP2C19 is generally similar to human CYP2C19 and CYP2C9 in its substrate recognition functionality. Copyright © 2015 John Wiley & Sons, Ltd.
Two star‐shaped tetranuclear Ru(II) complexes containing uncoordinated imidazole groups: synthesis, characterization, photophysical and pH sensing properties
Authors: Cheng Feixiang , Yu Shiwen , He Chixian , Ren Mingli , Yin Hongju 
Published: September 2015

AbstractTetrapodal ligands H4L1 and H4L2 containing imidazole groups have been synthesized by the reaction of 1,10‐phenanthroline‐5,6‐dione with 1,2,4,5‐tetrakis[(4‐formylphenoxy)methyl]benzene and 1,2,4,5‐tetrakis[(3‐formylphenoxy)methyl]benzene, respectively, in presence of NH4OAc. Two star‐shaped complexes [{Ru(bpy)2}4(μ4‐H4L1)](PF6)8 and [{Ru(bpy)2}4(μ4‐H4L2)](PF6)8 (bpy = 2,2′‐bipyridine) have been prepared by refluxing Ru(bpy)2Cl2·2H2O and each ligand in ethylene glycol. The deprotonated complexes [{Ru(bpy)2}4(μ4‐L1)](PF6)4 and [{Ru(bpy)2}4(μ4‐L2)](PF6)4 have been obtained by the reaction of sodium methoxide with [{Ru(bpy)2}4(μ4‐H4L1)](PF6)8 and [{Ru(bpy)2}4(μ4‐H4L2)](PF6)8, respectively, in methanol. The pH effects on the UV–vis light absorption and emission spectra of both complexes have been studied, and ground‐ and excited‐state ionization constants of both complexes have been derived. The photophysical properties of both complexes are strongly dependent on the solution pH. They act as proton‐induced off–on–off luminescent sensors through two successive deprotonation processes of imidazole groups, with a maximum on–off ratio of 8 in buffer solution at room temperature. Theoretical calculations for the highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital (LOMO) orbitals of bridging ligand are also presented for plausible explanations of the fluorescence changes. Copyright © 2015 John Wiley & Sons, Ltd.
Human whole‐blood culture system for ex vivo characterization of designer‐cell function
Authors: Schukur Lina , Geering Barbara , Fussenegger Martin 
Published: September 2015

ABSTRACTEncapsulated designer cells implanted into mice are currently used to validate the efficacy of therapeutic gene networks for the diagnosis and treatment of various human diseases in preclinical research. Because many human conditions cannot be adequately replicated by animal models, complementary and alternative procedures to test future treatment strategies are required. Here we describe a novel approach utilizing an ex vivo human whole‐blood culture system to validate synthetic biology‐inspired designer cell‐based treatment strategies. The viability and functionality of transgenic mammalian designer cells co‐cultured with primary human immune cells were characterized. We demonstrated that transgenic mammalian designer cells required adequate insulation from the human blood microenvironment to maintain viability and functionality. The biomaterial alginate‐(poly‐l‐lysine)‐alginate used to encapsulate the transgenic designer cells did neither affect the viability of primary granulocytes and lymphocytes nor the functionality of lymphocytes. Additionally, alginate‐encapsulated transgenic designer cells remained responsive to the release of the pro‐inflammatory cytokine tumor necrosis factor (TNF) from the whole‐blood culture upon exposure to bacterial lipopolysaccharide (LPS). TNF diffused into the alginate capsules, bound to the specific TNF receptors on the transgenic designer cells’ surface and triggered the expression of the reporter gene SEAP (human placental secreted alkaline phosphatase) that was rewired to the TNF‐specific signaling cascade. Human whole‐blood culture systems can therefore be considered as valuable complementary assays to animal models for the validation of synthetic circuits in genetically modified mammalian cells and may speed up preclinical research in a world of personalized medicine. Biotechnol. Bioeng. 2016;113: 588–597. © 2015 Wiley Periodicals, Inc.
Three‐dimensional printing of human skeletal muscle cells: An interdisciplinary approach for studying biological systems
Authors: Bagley James R. , Galpin Andrew J. 
Published: September 2015

AbstractInterdisciplinary exploration is vital to education in the 21st century. This manuscript outlines an innovative laboratory‐based teaching method that combines elements of biochemistry/molecular biology, kinesiology/health science, computer science, and manufacturing engineering to give students the ability to better conceptualize complex biological systems. Here, we utilize technology available at most universities to print three‐dimensional (3D) scale models of actual human muscle cells (myofibers) out of bioplastic materials. The same methodological approach could be applied to nearly any cell type or molecular structure. This advancement is significant because historically, two‐dimensional (2D) myocellular images have proven insufficient for detailed analysis of organelle organization and morphology. 3D imaging fills this void by providing accurate and quantifiable myofiber structural data. Manipulating tangible 3D models combats 2D limitation and gives students new perspectives and alternative learning experiences that may assist their understanding. This approach also exposes learners to 1) human muscle cell extraction and isolation, 2) targeted fluorescence labeling, 3) confocal microscopy, 4) image processing (via open‐source software), and 5) 3D printing bioplastic scale‐models (×500 larger than the actual cells). Creating these physical models may further student's interest in the invisible world of molecular and cellular biology. Furthermore, this interdisciplinary laboratory project gives instructors of all biological disciplines a new teaching tool to foster integrative thinking. © 2015 by The International Union of Biochemistry and Molecular Biology, 43:403–407, 2015.
Influence of verapamil on pharmacokinetics of pristimerin in rats
Authors: Gao Xiaodong , Zhang Yongjie , Wang Yongdong , Zhang Yijie , Wang Yixin , Liu Shuya , Gao Xiaohong 
Published: September 2015

AbstractThe aim of this study was to investigate the effects of verapamil on the pharmacokinetics of pristimerin in rats. A sensitive and reliable LC‐MS/MS method was developed and applied for the determination of pristimerin in rat plasma. The pharmacokinetics of orally administered pristimerin with and without verapamil pretreatment was investigated. The results indicated that, when the rats were pretreated with verapamil, the peak concentration of pristimerin increased from 189.13 to 277.53 ng/mL (46.7%), and the AUC0–t increased by approximately 82.0%. Additionally, the effects of verapamil on the absorption and metabolic stability of pristimerin were investigated using the Caco‐2 cell transwell model and rat liver microsomes. A markedly higher transport of pristimerin across the Caco‐2 cells was observed in the basolateral‐to‐apical direction and was abrogated in the presence of the P‐gp inhibitor, verapamil. These results indicated that P‐gp might be involved in the absorption of pristimerin. Of note, the metabolic half‐life of pristimerin was prolonged by the pretreatment with verapamil. In conclusion, verapamil could affect the pharmacokinetics of pristimerin, and it might work through increasing the absorption of pristimerin by inhibiting P‐gp, or through slowing down the metabolism of pristimerin in the rat liver. Copyright © 2015 John Wiley & Sons, Ltd.
Novel biomarker pipeline to probe the oxidation sites and oxidation degrees of hemoglobin in bovine erythrocytes exposed to oxidative stress
Authors: Zong Wansong , Wang Xiaoning , Yang Chuanxi , Du Yonggang , Sun Weijun , Xu Zhenzhen 
Published: September 2015

AbstractResearch on biomarkers for protein oxidation might give insight into the mechanistic mode of oxidative stress. In the work present here, a novel pipeline was established to probe the oxidation mechanism of bovine hemoglobin (Hb) with its oxidation products serving as the biomarkers. Reactive oxygen species generated by irradiation were used to mimic oxidative stress conditions to oxidize Hb in bovine erythrocytes. After Hb extraction and digestion, oxidized peptides in the tryptic fragments were assigned by comparison with the extracted ion chromatography spectra of native peptide from the control sample. Subsequent tandem mass spectrometry analysis of these peptides proved that oxidation was limited to partially exposed amino acid residues (α‐Phe36, β‐Met1, β‐Trp14, for instance) in Hb. Quantitation analysis on these oxidized peptides showed that oxidation degrees of target sites had positive correlations with the extended oxidation dose and the oxidation processes were also controlled by residues types. Compared with the conventional protein carbonyl assay, the identified oxidized products were feasibility biomarkers for Hb oxidation, indicating that the proposed biomarker pipeline was suitable to provide specific and valid information for protein oxidation. Copyright © 2015 John Wiley & Sons, Ltd.