bluuebunny/crossref_metadata_2025_split huggingface dataset:
Innate Immune Mechanisms: Nonself Recognition
Authors: Quah Ben JC , Parish Christopher R 
Published: August 2015

Abstract

The initial defence of the body against pathogens relies on the innate immune system. The innate immune system recognises unique molecular patterns expressed by pathogens, referred to as pathogen‐associated molecular patterns (
PAMPs
), through receptors known as pattern recognition molecules (
PRMs
).
PRMs
are a diverse range of molecules and include secreted proteins, transmembrane proteins and cytosolic proteins. These molecules sense extracellular and intracellular pathogens and induce a number of responses to help aid in pathogen destruction including phagocytosis through opsonisation, cytokine production and activation of complement. In addition to pathogen sensing, host cells express proteins, the complement regulatory proteins that protect them from attack by the alternative pathway of complement activation, whereas foreign organisms lack these protective proteins and are, therefore, susceptible to complement attack.

Key Concepts

The innate immune system recognises pathogen‐associated molecular patterns (PAMPs) that are unique to pathogens.

Cells of the innate immune system express a large range of pattern recognition molecules (PRM) that bind to PAMPs.

PRMs are a diverse range of molecules and include secreted proteins, membrane‐associated proteins and cytosolic proteins.

PRMs induce a number of host defence mechanisms upon recognition of PAMPs, including phagocytosis, cytokine production and complement activation.

Host cells express complement regulatory proteins that protect them from attack by innate mechanisms.
Tumour Antigens Recognised by Antibodies
Authors: Luborsky Judith 
Published: August 2015

Abstract

Humoral and cellular immune responses to tumour antigens occur during tumourigenesis. Since 1965, there has been an ongoing search for cancer‐specific antibodies as these have potential applications as specific diagnostic and therapeutic tools. Serum antibodies from cancer patients have been used to identify hundreds of tumour antigens. Owing to the biochemical heterogeneity of tumours, even of the same type, each patient has a slightly different repertoire of autoantibodies. However, there is an overall characteristic polyclonal signature for specific tumour types. Thus, multi‐antigen assays to detect cancer signatures are in development as diagnostic tests. For antigen‐targeted therapy, monoclonal antibodies to individual antigens have been produced and some are
FDA
approved for cancer treatment.

Key Concepts

Autoantibodies against aberrant or overexpressed tumour antigens are induced during tumour development.

Tumour‐associated autoantibodies have potential for cancer diagnosis and prognosis.

Individual autoantibodies have a relatively low sensitivity while multiplex antigen arrays that detect multiple autoantibodies provide a higher specificity and sensitivity for tumour detection.

Serum autoantibodies have been useful in identifying tumour antigens that can be used to characterise tumours and as therapeutic targets.

Monoclonal antibodies against specific tumour antigens can be produced in the laboratory.

Multiple monoclonal antibodies produced against cancer‐specific antigens have been FDA approved for cancer therapy.
Fluorescent Probes Used for Measuring Intracellular Calcium
Authors: Oheim Martin 
Published: August 2015

Abstract

Calcium (Ca
2+
) is a ubiquitous messenger in many intracellular signalling cascades. With resting Ca
2+
concentrations around 100
nM
and peak amplitudes of Ca
2+
transients of the order of 10–100 μM, the specificity of the diverse Ca
2+
signals comes to a lesser degree from the affinities of the different biological Ca
2+
sensors and from the spatio‐temporal compartmentalisation of the Ca
2+
signal into subcellular nano‐ and microdomains. The measurement of such local and short‐lived Ca
2+
signals presents a major experimental challenge. Ca
2+
imaging with fluorescent indicators has initially involved synthetic small‐molecule chemical Ca
2+
indicators. While a large choice exists among molecules with different hues and Ca
2+
affinities and these molecules come in salt and ester forms for single‐cell or bulk loading, respectively, the subcellular targeting of Ca
2+
indicators and their long‐term use in live animals have remained problematic. The advent of genetically encoded Ca
2+
indicators that can be linked to different retention and targeting domains now permits the readout of local Ca
2+
signals, the targeting to different subcellular regions or cell types in intact tissue, the measurement of organelle Ca
2+
as well as long‐term recordings over months. For the detection of Ca
2+
nanodomains, hybrid organic–inorganic Ca
2+
nanobiosensors start to emerge as a promising alternative.

Key Concepts

Ca
2+
signals are local, both in space and time, and their spread and kinetics are shaped by the presence of endogeneous Ca
2+
‐binding molecules (Ca
2+
buffers).

Ca
2+
indicators are fluorescent exogeneous Ca
2+
buffers and as such distort the Ca
2+
signal to be measured.

Ca
2+
‐related fluorescence does not equal Ca
2+
concentration.

Genetically encoded Ca
2+
indicators are a powerful alternative to chemical small‐molecule organic indicators.

Measured Ca
2+
signals depend not only on the biological process studied and the properties of the fluorescent Ca
2+
indicator but also on the microscope and image acquisition parameters.

The measurement of local (rather than temporally and spatially averaged) Ca
2+
signals requires confinement of the dye volume, the fluorescence excitation volume, the fluorescence readout volume or a combination of these.
Glycolipid Presentation by
CD1
Authors: Layre Emilie , Mazurek Jolanta , Gilleron Martine 
Published: August 2015

Abstract

CD1
molecules constitute a family of nonpolymorphic,
MHC
class I‐like antigen‐presenting glycoproteins, which bind amphipathic lipid antigens and present them to T cells. These proteins are involved in presenting a broad range of self and foreign lipid antigens to variable T lymphocytes and natural killer T cells bearing a semi‐invariant T‐cell receptor (
iNKT
). It has become clear that the recognition of lipid antigens by T cells plays an important role in the detection and clearance of pathogens, immune response regulation and tissue surveillance.

Key Concepts

Self and microbial lipids and glycolipids are recognised by T cells.

Hydrophobic pockets of CD1 proteins allow lipid antigens to be loaded via their alkyl chains, while the hydrophilic part of the antigen is presented to T‐cell receptors.

CD1 proteins are non‐polymorphic and predominantly expressed on the surface of antigen‐presenting cells.

Glycolipids can be processed into smaller antigenic structures in the endosomal pathway.

CD1e, a soluble protein found in late endosomes, assists in lipid antigen editing and loading onto other CD1 proteins.

CD1‐restricted T cells express αβ or γδ TCR and are found in CD4
+
, CD8
+
or double‐negative T‐cell populations.

The frequency of autoreactive T cells is high among CD1‐restricted T cells.
A Polystyrene‐Bound Triphenylphosphine Gold(I) Catalyst for the Glycosylation of Glycosyl ortho‐Hexynylbenzoates
Authors: Zhu Yugen , Laval Stéphane , Tang Yu , Lian Gaoyan , Yu Biao 
Published: August 2015

AbstractThe efficacy of the heterogeneous polystyrene‐bound triphenylphosphine gold(I) catalyst 3 (PS‐[Ph3PAuINTf2]; PS=polystyrene; Tf=trifluoromethanesulfonyl) in the activation of glycosyl ortho‐hexynylbenzoates for glycosylation is demonstrated. The shelf‐stable catalyst 3 (and its precursor 2, PS‐[Ph3PAuICl]) were fully characterized by elemental analysis, X‐ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), and scanning electron microscopy (SEM), and showed remarkable catalytic activities and recyclability in glycosylation reactions as well as in the skeletal rearrangement of the 1,6‐enyne 4. EDS analysis demonstrated that the phosphine ligand binds the gold strongly and prevents the leaching of the metal.
Disulfonimid‐katalysierte asymmetrische Reduktion von N‐Alkyliminen
Authors: Wakchaure Vijay N. , Kaib Philip S. J. , Leutzsch Markus , List Benjamin 
Published: August 2015

AbstractEine durch ein chirales Disulfonimid (DSI) katalysierte asymmetrische Reduktion von N‐Alkyliminen mit Hantzsch‐Estern als Wasserstoffquelle in Gegenwart von Boc2O wurde entwickelt. Diese Reaktion liefert Boc‐geschützte N‐Alkylamine mit ausgezeichneten Ausbeuten und Enantioselektivitäten. Die Methode toleriert viele verschiedene Alkylamine, was die Möglichkeit einer allgemeinen reduktiven Kreuzkupplung von Ketonen mit verschiedenen Aminen aufzeigt, und wurde in der Synthese der Wirkstoffe (S)‐Rivastigmin, NPS‐R‐568‐Hydrochlorid und (R)‐Fendiline angewendet.
Quantitative Measurement of Transmitters in Individual Vesicles in the Cytoplasm of Single Cells with Nanotip Electrodes
Authors: Li Xianchan , Majdi Soodabeh , Dunevall Johan , Fathali Hoda , Ewing Andrew G. 
Published: August 2015

AbstractThe quantification of vesicular transmitter content is important for studying the mechanisms of neurotransmission and malfunction in disease, and yet it is incredibly difficult to measure the tiny amounts of neurotransmitters in the attoliter volume of a single vesicle, especially in the cell environment. We introduce a novel method, intracellular vesicle electrochemical cytometry. A nanotip conical carbon‐fiber microelectrode was used to electrochemically measure the total content of electroactive neurotransmitters in individual nanoscale vesicles in single PC12 cells as these vesicles lysed on the electrode inside the living cell. The results demonstrate that only a fraction of the quantal neurotransmitter content is released during exocytosis. These data support the intriguing hypothesis that the vesicle does not open all the way during the normal exocytosis process, thus resulting in incomplete expulsion of the vesicular contents.
Conversion of Carbon Dioxide by Methane Reforming under Visible‐Light Irradiation: Surface‐Plasmon‐Mediated Nonpolar Molecule Activation
Authors: Liu Huimin , Meng Xianguang , Dao Thang Duy , Zhang Huabin , Li Peng , Chang Kun , Wang Tao , Li Mu , Nagao Tadaaki , Ye Jinhua 
Published: August 2015

AbstractA novel CO2 photoreduction method, CO2 conversion through methane reforming into syngas (DRM) was adopted as an efficient approach to not only reduce the environmental concentration of the greenhouse gas CO2 but also realize the net energy storage from solar energy to chemical energy. For the first time it is reported that gold, which was generally regarded to be inactive in improving the performance of a catalyst in DRM under thermal conditions, enhanced the catalytic performance of Rh/SBA‐15 in DRM under visible‐light irradiation (1.7 times, CO2 conversion increased from 2100 to 3600 μmol g−1 s−1). UV/Vis spectra and electromagnetic field simulation results revealed that the highly energetic electrons excited by local surface plasmon resonances of Au facilitated the polarization and activation of CO2 and CH4 with thermal assistance. This work provides a new route for CO2 photoreduction and offers a distinctive method to photocatalytically activate nonpolar molecules.
Visible‐Light‐Driven Photoisomerization and Increased Rotation Speed of a Molecular Motor Acting as a Ligand in a Ruthenium(II) Complex
Authors: Wezenberg Sander J. , Chen Kuang‐Yen , Feringa Ben L. 
Published: August 2015

AbstractToward the development of visible‐light‐driven molecular rotary motors, an overcrowded alkene‐based ligand and the corresponding ruthenium(II) complex is presented. In our design, a 4,5‐diazafluorenyl coordination motif is directly integrated into the motor function. The photochemical and thermal isomerization behavior has been studied by UV/Vis and NMR spectroscopy. Upon coordination to a RuII bipyridine complex, the photoisomerization process can be driven by visible (λmax=450 nm) instead of UV light and furthermore, a large increase of the speed of rotation is noted. DFT calculations point to a contraction of the diazafluorenyl lower half upon metal‐coordination resulting in reduced steric hindrance in the “fjord region” of the molecule. Consequently, it is shown that metal‐ligand interactions can play an important role in the adjustment of both photophysical and thermodynamic properties of molecular motors.
Mononuclear Nonheme Iron(III)‐Iodosylarene and High‐Valent Iron‐Oxo Complexes in Olefin Epoxidation Reactions
Authors: Wang Bin , Lee Yong‐Min , Seo Mi Sook , Nam Wonwoo 
Published: August 2015

AbstractHigh‐spin iron(III)‐iodosylarene complexes are highly reactive in the epoxidation of olefins, in which epoxides are formed as the major products with high stereospecificity and enantioselectivity. The reactivity of the iron(III)‐iodosylarene intermediates is much greater than that of the corresponding iron(IV)‐oxo complex in these reactions. The iron(III)‐iodosylarene species—not high‐valent iron(IV)‐oxo and iron(V)‐oxo species—are also shown to be the active oxidants in catalytic olefin epoxidation reactions. The present results are discussed in light of the long‐standing controversy on the one oxidant versus multiple oxidants hypothesis in oxidation reactions.
Chiral γ‐Lactams by Enantioselective Palladium(0)‐Catalyzed Cyclopropane Functionalizations
Authors: Pedroni Julia , Cramer Nicolai 
Published: August 2015

AbstractCyclopropanes fused to pyrrolidines are important structural features found in a number of marketed drugs and development candidates. Typically, their synthesis involves the cyclopropanation of a dihydropyrrole precursor. Reported herein is a complementary approach which employs a palladium(0)‐catalyzed CH functionalization of an achiral cyclopropane to close the pyrrolidine ring in an enantioselective manner. In contrast to aryl–aryl couplings, palladium(0)‐catalyzed CH functionalizations involving the formation of C(sp3)C(sp3) bonds of saturated heterocycles are very scarce. The presented strategy yields cyclopropane‐fused γ‐lactams from chloroacetamide substrates. A bulky Taddol phosphonite ligand in combination with adamantane‐1‐carboxylic acid as a cocatalyst provides the γ‐lactams in excellent yields and enantioselectivities.
Optical, electrical, and electrochemical properties of graphene based water soluble polyaniline composites
Authors: Meriga Venkanna , Valligatla Sreeramulu , Sundaresan Sivaprakash , Cahill Caroline , Dhanak Vinod R. , Chakraborty Amit K. 
Published: August 2015

ABSTRACTPolyaniline (PANI) is one of the most common polymers known for its conducting properties. However, poor water solubility limits its applications. In this work, PANI has been functionalized with sulfonic acid groups to produce sulfonated PANI (SPANI) offering excellent solubility in water. To compensate for the decrease of electrical conductivity due to functionalization, SPANI was combined with reduced graphene oxide (RGO) to form SPANI/RGO composites with interesting optical, thermal, and electrical properties. The composites have been characterized using X‐ray diffraction (XRD), field emission scanning electron microscopy, UV–vis absorption spectroscopy, Raman spectroscopy, Fourier‐transform infrared spectroscopy, X‐ray photoelectron spectroscopy, thermogravimetric analysis, cyclic voltammetry, and four probe electrical conductivity measurement. The SPANI/RGO composites show increased thermal stability, reduced optical band gap and improved electrochemical properties compared with the pure polymer. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 42766.
Heterologous production of a feruloyl esterase from Pleurotus sapidus synthesizing feruloyl‐saccharide esters
Authors: Kelle Sebastian , Nieter Annabel , Krings Ulrich , Zelena Katerina , Linke Diana , Berger Ralf G. 
Published: August 2015

AbstractThe feruloyl esterase (FAE) gene EST1 from the basidiomycete Pleurotus sapidus was heterologously expressed in Escherichia coli and Pichia pastoris. Catalytically active recombinant Est1 was secreted using P. pastoris as a host. For expression in P. pastoris, the expression vector pPIC9K was applied. The EST1 gene was cloned with an N‐terminal α‐mating factor pre–pro sequence and expressed under the control of a methanol inducible alcohol oxidase 1 promotor. Est1 was purified to homogeneity using ion exchange and hydrophobic interaction chromatography. The recombinant Est1 showed optima at pH 5.0 and 50 °C, and released ferulic acid from saccharide esters and from the natural substrate destarched wheat bran. Substrate specificity profile and descriptor‐based analysis demonstrated unique properties, showing that Est1 did not fit into the current FAE classification model. Transferuloylation synthesis of feruloyl‐saccharide esters was proven for mono‐ and disaccharides.
Intensified fractionation of brewery yeast waste for the recovery of invertase using aqueous two‐phase systems
Authors: De León‐González Grecia , González‐Valdez José , Mayolo‐Deloisa Karla , Rito‐Palomares Marco 
Published: August 2015

AbstractThe potential recovery of high‐value products from brewery yeast waste confers value to this industrial residue. Aqueous two‐phase systems (ATPS) have demonstrated to be an attractive alternative for the primary recovery of biological products and are therefore suitable for the recovery of invertase from this residue. Sixteen different polyethylene glycol (PEG)–potassium phosphate ATPS were tested to evaluate the effects of PEG molecular weight (MW) and tie‐line length (TLL) upon the partition behavior of invertase. Concentrations of crude extract from brewery yeast waste were then varied in the systems that presented the best behaviors to intensify the potential recovery of the enzyme. Results show that the use of a PEG MW 400 g mol−1 system with a TLL of 45.0% (w/w) resulted in an invertase bottom phase recovery with a purification factor of 29.5 and a recovery yield of up to 66.2% after scaling the system to a total weight of 15.0 g. This represents 15.1 mg of invertase per mL of processed bottom phase. With these results, a single‐stage ATPS process for the recovery of invertase is proposed.
Now or Later? Attentional Processing and Intertemporal Choice
Authors: Franco‐Watkins Ana M. , Mattson Richard E. , Jackson Marc D. 
Published: August 2015

AbstractThe tendency to discount future prospects in lieu of smaller immediate outcomes is known as temporal discounting. The current work used eye‐tracking methodology to examine attentional processing to different elements of choice during an intertemporal decision task. Our findings reveal that those who tend to prefer the immediate option demonstrate attentional biases that were predictive of choice. When losses were at stake, selective attention biases also predicted unique variance in self‐report measures of risk taking, impulsivity, and self‐control beyond what was accounted for by a discounting parameter (k), a typical method for summarizing intertemporal choice data. Overall, our findings suggest that eye‐tracking measures of selective attention may allow for a better theoretical understanding of the mechanisms and processes involved in intertemporal choice. Copyright © 2015 John Wiley & Sons, Ltd.
Synergy between Palladium and Potassium Species for Efficient Activation of Carbon Monoxide in the Synthesis of Dimethyl Carbonate
Authors: Dong Yuanyuan , Shen Yongli , Zhao Yujun , Wang Shengping , Ma Xinbin 
Published: August 2015

AbstractThe front cover artwork for Issue 16/2015 is provided by Prof. Xinbin Ma and co‐workers from Tianjin University (P.R. China). The image shows the cooperative effect of Pd and K species for the activation of CO in the carbonylation of methyl nitrite to synthesize dimethyl carbonate. See the Full Paper itself at http://dx.doi.org/10.1002/cctc.201500317.
Comparison of Cyclic and Square Wave Voltammetry of Irreversible EC Mechanisms
Authors: Čižmek Lara , Komorsky‐Lovrić Šebojka , Lovrić Milivoj 
Published: August 2015

AbstractA theoretical model of EC mechanism that consists of reversible electrode reaction and totally irreversible chemical reaction is developed for cyclic and square wave voltammetry. Critical kinetic parameters are calculated and their application for the determination of rate constant of chemical reaction is demonstrated. It is shown that this constant may be used for the estimation of enhanced activity of antioxidants.
Far‐Red Emitting Fluorescent Dyes for Optical Nanoscopy: Fluorinated Silicon–Rhodamines (SiRF Dyes) and Phosphorylated Oxazines
Authors: Kolmakov Kirill , Hebisch Elke , Wolfram Thomas , Nordwig Lars A. , Wurm Christian A. , Ta Haisen , Westphal Volker , Belov Vladimir N. , Hell Stefan W. 
Published: August 2015

AbstractFar‐red emitting fluorescent dyes for optical microscopy, stimulated emission depletion (STED), and ground‐state depletion (GSDIM) super‐resolution microscopy are presented. Fluorinated silicon–rhodamines (SiRF dyes) and phosphorylated oxazines have absorption and emission maxima at about λ≈660 and 680 nm, respectively, possess high photostability, and large fluorescence quantum yields in water. A high‐yielding synthetic path to introduce three aromatic fluorine atoms and unconventional conjugation/solubilization spacers into the scaffold of a silicon–rhodamine is described. The bathochromic shift in SiRF dyes is achieved without additional fused rings or double bonds. As a result, the molecular size and molecular mass stay quite small (<600 Da). The use of the λ=800 nm STED beam instead of the commonly used one at λ=750–775 nm provides excellent imaging performance and suppresses re‐excitation of SiRF and the oxazine dyes. The photophysical properties and immunofluorescence imaging performance of these new far‐red emitting dyes (photobleaching, optical resolution, and switch‐off behavior) are discussed in detail and compared with those of some well‐established fluorophores with similar spectral properties.
Ruthenium(II) and Osmium(II) Vinyl Complexes as Highly Sensitive and Selective Chromogenic and Fluorogenic Probes for the Sensing of Carbon Monoxide in Air
Authors: Toscani Anita , Marín‐Hernández Cristina , Moragues María E. , Sancenón Félix , Dingwall Paul , Brown Neil J. , Martínez‐Máñez Ramón , White Andrew J. P. , Wilton‐Ely James D. E. T. 
Published: August 2015

AbstractThe detection of carbon monoxide in solution and air has been achieved using simple, inexpensive systems based on the vinyl complexes [M(CHCHR)Cl(CO)(BTD)(PPh3)2] (R=aryl, BTD=2,1,3‐benzothiadiazole). Depending on the nature of the vinyl group, chromogenic and fluorogenic responses signalled the presence of this odourless, tasteless, invisible, and toxic gas. Solutions of the complexes in CHCl3 underwent rapid change between easily differentiated colours when exposed to air samples containing CO. More significantly, the adsorption of the complexes on silica produced colorimetric probes for the naked‐eye detection of CO in the gas phase. Structural data for key species before and after the addition of CO were obtained by means of single X‐ray diffraction studies. In all cases, the ruthenium and osmium vinyl complexes studied showed a highly selective response to CO with exceptionally low detection limits. Naked‐eye detection of CO at concentrations as low as 5 ppb in air was achieved with the onset of toxic levels (i.e., 100 ppm), thus resulting in a remarkably clear colour change. Moreover, complexes bearing pyrenyl, naphthyl, and phenanthrenyl moieties were fluorescent, and greater sensitivities were achieved (through turn‐on emission fluorescence) in the presence of CO both in solution and air. This behaviour was explored computationally using time‐dependent density functional theory (TDDFT) experiments. In addition, the systems were shown to be selective for CO over all other gases tested, including water vapour and common organic solvents. Supporting the metal complexes on cellulose strips for use in an existing optoelectronic device allows numerical readings for the CO concentration to be obtained and provision of an alarm system.