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91.
Bernadette B. Bagon Ju Kyoung Oh Valerie Diane V. Valeriano Edward Alain B. Pajarillo Dae-Kyung Kang 《Molecules (Basel, Switzerland)》2021,26(18)
Lactobacillus sp. have long been studied for their great potential in probiotic applications. Recently, proteomics analysis has become a useful tool for studies on potential lactobacilli probiotics. Specifically, proteomics has helped determine and describe the physiological changes that lactic acid bacteria undergo in specific conditions, especially in the host gut. In particular, the extracellular proteome, or exoproteome, of lactobacilli contains proteins specific to host– or environment–microbe interactions. Using gel-free, label-free ultra-high performance liquid chromatography tandem mass spectrometry, we explored the exoproteome of the probiotic candidate Lactobacillus mucosae LM1 subjected to bile treatment, to determine the proteins it may use against bile stress in the gut. Bile stress increased the size of the LM1 exoproteome, secreting ribosomal proteins (50S ribosomal protein L27 and L16) and metabolic proteins (lactate dehydrogenase, phosphoglycerate kinase, glyceraldehyde-3-phosphate dehydrogenase and pyruvate dehydrogenases, among others) that might have moonlighting functions in the LM1 bile stress response. Interestingly, membrane-associated proteins (transporters, peptidase, ligase and cell division protein ftsH) were among the key proteins whose secretion were induced by the LM1 bile stress response. These specific proteins from LM1 exoproteome will be useful in observing the proposed bile response mechanisms via in vitro experiments. Our data also reveal the possible beneficial effects of LM1 to the host gut. 相似文献
92.
93.
A benzophenone‐naphthalimide derivative as versatile photoinitiator of polymerization under near UV and visible lights 下载免费PDF全文
Jing Zhang Nicolas Zivic Frédéric Dumur Pu Xiao Bernadette Graff Didier Gigmes Jean Pierre Fouassier Jacques Lalevée 《Journal of polymer science. Part A, Polymer chemistry》2015,53(3):445-451
A benzophenone‐naphthalimide derivative (BPND) bearing tertiary amine groups has been developed as a high‐performance photoinitiator in combination with 2,4,6‐tris(trichloromethyl)‐1,3,5‐triazine or an iodonium salt for both the free radical polymerization (FRP) of acrylates and the cationic polymerization (CP) of epoxides upon exposure to near UV and visible LEDs (385–470 nm). BPND can even produce radicals without any added hydrogen donor. The photochemical mechanisms are studied by molecular orbital calculations, steady state photolysis, electron spin resonance spin trapping, fluorescence, cyclic voltammetry and laser flash photolysis techniques. These novel BPND based photoinitiating systems exhibit an efficiency higher than that of the well‐known camphorquinone‐based systems (FRP and CP) or comparable to that of bis(2,4,6‐trimethylbenzoyl)‐phenylphosphineoxide (FRP at λ ≤ 455 nm). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 445–451 相似文献
94.
Binita SutharAnuar Aldongarov Irina S. IrgibaevaMitra Moazzen Bernadette T. Donovan-MerkertJon W. Merkert Thomas A. Schmedake 《Polyhedron》2012,31(1):754-758
Various salts of tetracationic tris(2,2′-bipyridine)silicon(IV) and bis(2,2′;6′,2″-terpyridine)silicon(IV) were synthesized by reaction of SiI4 with the appropriate ligand followed by metathesis reactions. The resulting salts exhibit multiple, chemically reversible one-electron reduction waves that are significantly shifted to less negative reduction potentials than the corresponding ruthenium analogs. The salts also exhibit anion dependent ion pair charge transfer bands throughout the visible spectrum. Weak, low energy emission is observed from Si(bipy)3Br4 and Si(terpy)2Br4 in the solid state at 77 K when the sample is excited in the ion pair charge transfer band. 相似文献
95.
Sara J. Fraser Arun K. Natarajan Austina S. S. Clark Bernadette K. Drummond Keith C. Gordon 《Journal of Raman spectroscopy : JRS》2015,46(2):202-210
Raman spectroscopy was used to chemically map lesions associated with molar–incisor hypomineralisation in human teeth. Three teeth with hypomineralised lesions of differing severity, described as white, yellow or brown, were mapped using integral ratios of major component bands (hydroxyapatite, amide I and b‐type carbonate) and principal component analysis scores values. These lesions were found to contain depleted levels of mineral (hydroxyapatite) compared with those of healthy enamel. Principal component analysis also highlighted changes in the phosphate structure and variations in various organic constituents. These variations were consistent with increased disorder in the mineral component of the hypomineralised tooth lesions. Scanning electron microscopy–energy dispersive X‐ray spectroscopy supported the findings based on Raman spectroscopy. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
96.
Julien Gigault Wenjing Zhang Gaetane Lespes Bernadette Charleux Bruno Grassl 《Analytica chimica acta》2014
The aim of this work is to present a method based on asymmetric flow-field-flow-fractionation coupled on-line to a static light scattering (AF4-UV-SLS) detector to characterize self-assembled nanofibers (NFs). The method developed herein allows the determination of both the length distribution of the NFs as well as the distribution in terms of aggregation number per unit length (Agg). Given the remaining synthetic challenges of better controlling the structural homogeneity and particle dimensions, the NF length and aggregation number per unit length are becoming essential for the improvement and control of their chemical processes and a better understanding of their properties. The results obtained with this AF4-UV-SLS method indicate that a well-resolved NF length distribution characterization and Agg determination were attained. These results provide critical information concerning the physical properties of the investigated NFs and open the door to the characterization of new self-assembled polymers with various asymmetrical architectures. 相似文献
97.
Actis P Caulliez G Shul G Opallo M Mermoux M Marcus B Boukherroub R Szunerits S 《Langmuir : the ACS journal of surfaces and colloids》2008,24(12):6327-6333
The paper reports on the chemical functionalization of glassy carbon electrodes with 4-bromobenzene (4-BBDT) and 4-(4'-nitrophenylazo)benzene diazonium tetrafluoroborate (4-NAB) salts in ionic liquids. The reaction was carried out at room temperature in air without any external electrical bias in either hydrophobic (1-butyl-3-methylimidazolium hexafluorophosphate) or hydrophilic (1-butyl-3-methylimidazolium methyl sulfate) ionic liquids. The resulting surfaces were characterized using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and electrochemical measurements. Electrochemical reduction of the terminal nitro groups allowed the determination of surface coverage and formation of an amine-terminated carbon surfaces. The results were compared to glassy carbon chemically modified in an aqueous solution in the presence of 1% sodium dodecyl sulfate (SDS) with the same diazonium salt. Furthermore, Raman spectroscopy coupled with electrochemical measurements allowed to distinguish between the reduction of -NO2 to -NH2 group and the -N=N- to -NH-NH- bond. 相似文献
98.
Coaxial metal and magnetic alloy nanotubes in polycarbonate templates by electroless deposition 总被引:1,自引:0,他引:1
James F. Rohan Declan P. Casey Bernadette M. Ahern Fernando M.F. Rhen Saibal Roy David Fleming Simon E. Lawrence 《Electrochemistry communications》2008,10(9):1419-1422
We present a novel technique for the preparation of coaxial metal and magnetic alloy nanotubes, which is demonstrated for the coaxial nanotubes of Ni/Co and Ni/CoNiFe alloys deposited in activated polycarbonate templates using electroless plating. For each metal or alloy the tube wall thickness was controlled to be less than 100 nm. The process involved two consecutive deposition steps from hypophosphite and/or borane reducing agent based electroless plating solutions. We further characterise the magnetic properties of the ternary magnetic alloy films and coaxial nanotubes. The coaxial tubes show homogenous wall thickness and composition, which is delineated from the magnetic measurements. 相似文献
99.
de Almeida Leone P Carroll AR Towerzey L King G McArdle BM Kern G Fisher S Hooper JN Quinn RJ 《Organic letters》2008,10(12):2585-2588
Bioassay-guided fractionation of the methanol extract of the Australian sponge Neopetrosia exigua led to the isolation of exiguaquinol (2), a new pentacyclic hydroquinone that inhibited Helicobacter pylori glutamate racemase (MurI) with an IC(50) of 4.4 microM. Its structure and relative configuration were assigned on the basis of spectroscopic data. Exiguaquinol (2), bearing a novel pentacyclic ring skeleton, is the first natural product to show inhibition of H. pylori MurI. Its protein-ligand modeling is also discussed. 相似文献
100.
Dr. Claudia Herrera León Noel Angelo Kalacas Dr. Alejandra Mier Dr. Peyman Sakhaii Dr. Franck Merlier Elise Prost Dr. Irene Maffucci Dr. Valentina Montagna Dr. Helena Mora-Radó Dr. Pradeep K. Dhal Dr. Bernadette Tse Sum Bui Prof. Dr. Karsten Haupt 《Angewandte Chemie (International ed. in English)》2023,62(34):e202306274
Tumor Necrosis Factor-α (TNF-α) is a cytokine that is normally produced by immune cells when fighting an infection. But, when too much TNF-α is produced as in autoimmune diseases, this leads to unwanted and persistent inflammation. Anti-TNF-α monoclonal antibodies have revolutionized the therapy of these disorders by blocking TNF-α and preventing its binding to TNF-α receptors, thus suppressing the inflammation. Herein, we propose an alternative in the form of molecularly imprinted polymer nanogels (MIP-NGs). MIP-NGs are synthetic antibodies obtained by nanomoulding the 3-dimensional shape and chemical functionalities of a desired target in a synthetic polymer. Using an in-house developed in silico rational approach, epitope peptides of TNF-α were generated and ‘synthetic peptide antibodies’ were prepared. The resultant MIP-NGs bind the template peptide and recombinant TNF-α with high affinity and selectivity, and can block the binding of TNF-α to its receptor. Consequently they were applied to neutralize pro-inflammatory TNF-α in the supernatant of human THP-1 macrophages, leading to a downregulation of the secretion of pro-inflammatory cytokines. Our results suggest that MIP-NGs, which are thermally and biochemically more stable and easier to manufacture than antibodies, and cost-effective, are very promising as next generation TNF-α inhibitors for the treatment of inflammatory diseases. 相似文献