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51.
Vincent S. D. Voet Gerrit ten Brinke Katja Loos 《Journal of polymer science. Part A, Polymer chemistry》2014,52(20):2861-2877
Poly(vinylidene fluoride) (PVDF) has reached the second largest production volume of fluoropolymers in recent years, and its popularity can be ascribed to high thermal stability and chemical inertness combined with its ferroelectric behavior. Copolymerization of vinylidene fluoride with other monomers leads to a wide variety of products with modified or improved properties. Besides commercially available fluorinated random copolymers, well‐defined block‐, graft, and alternating copolymers based on PVDF received more attention in recent years. PVDF‐containing block copolymers that may self‐assemble into well‐ordered morphologies are of particular interest, being potential precursors for functional nanostructured materials applicable in membranes and electronics. This Highlight provides an overview of the routes developed towards these materials via conventional and controlled polymerization techniques. In addition, it discusses their nanoscopic phase behavior and current and potential applications. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2861–2877 相似文献
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Maa Mavri Katja Spiess Mette Marie Rosenkilde Catrin Sian Rutland Milka Vrecl Valentina Kubale 《Molecules (Basel, Switzerland)》2020,25(23)
Endocytosis is a fundamental process involved in trafficking of various extracellular and transmembrane molecules from the cell surface to its interior. This enables cells to communicate and respond to external environments, maintain cellular homeostasis, and transduce signals. G protein-coupled receptors (GPCRs) constitute a family of receptors with seven transmembrane alpha-helical domains (7TM receptors) expressed at the cell surface, where they regulate physiological and pathological cellular processes. Several herpesviruses encode receptors (vGPCRs) which benefits the virus by avoiding host immune surveillance, supporting viral dissemination, and thereby establishing widespread and lifelong infection, processes where receptor signaling and/or endocytosis seem central. vGPCRs are rising as potential drug targets as exemplified by the cytomegalovirus-encoded receptor US28, where its constitutive internalization has been exploited for selective drug delivery in virus infected cells. Therefore, studying GPCR trafficking is of great importance. This review provides an overview of the current knowledge of endocytic and cell localization properties of vGPCRs and methodological approaches used for studying receptor internalization. Using such novel approaches, we show constitutive internalization of the BILF1 receptor from human and porcine γ-1 herpesviruses and present motifs from the eukaryotic linear motif (ELM) resources with importance for vGPCR endocytosis. 相似文献
54.
Katja Kavkler ?iga Šmit David JezeršekDiane Eichert Andrej Demšar 《Polymer Degradation and Stability》2011,96(6):1081-1086
We have examined specimens of historical biodeteriorated cellulose textiles using synchrotron radiation and conventional source FTIR spectroscopy. The main aim of our research was to investigate structural changes caused by ageing and biodeterioration in different types of cellulose fibres. We compared the results, obtained with both methods regarding spectral quality and information obtained with each method. Additionally, we obtained mapping images of the cross sections of the investigated specimens using synchrotron FTIR in order to analyze structural changes in cross sections, caused due to biodeterioration. 相似文献
55.
Dettmer K Nürnberger N Kaspar H Gruber MA Almstetter MF Oefner PJ 《Analytical and bioanalytical chemistry》2011,399(3):1127-1139
Trypsin/ethylenediaminetetraacetic acid (EDTA) treatment and cell scraping in a buffer solution were compared for harvesting
adherently growing mammalian SW480 cells for metabolomics studies. In addition, direct scraping with a solvent was tested.
Trypsinated and scraped cell pellets were extracted using seven different extraction protocols including pure methanol, methanol/water,
pure acetone, acetone/water, methanol/chloroform/water, methanol/isopropanol/water, and acid–base methanol. The extracts were
analyzed by GC-MS after methoximation/silylation and derivatization with propyl chloroformate, respectively. The metabolic
fingerprints were compared and 25 selected metabolites including amino acids and intermediates of energy metabolism were quantitatively
determined. Moreover, the influence of freeze/thaw cycles, ultrasonication and homogenization using ceramic beads on extraction
yield was tested. Pure acetone yielded the lowest extraction efficiency while methanol, methanol/water, methanol/isopropanol/water,
and acid–base methanol recovered similar metabolite amounts with good reproducibility. Based on overall performance, methanol/water
was chosen as a suitable extraction solvent. Repeated freeze/thaw cycles, ultrasonication and homogenization did not improve
overall metabolite yield of the methanol/water extraction. Trypsin/EDTA treatment caused substantial metabolite leakage proving
it inadequate for metabolomics studies. Gentle scraping of the cells in a buffer solution and subsequent extraction with methanol/water
resulted on average in a sevenfold lower recovery of quantified metabolites compared with direct scraping using methanol/water,
making the latter one the method of choice to harvest and extract metabolites from adherently growing mammalian SW480 cells. 相似文献
56.
Tareq M.A. Al-Shboul Lian Yu Katja Wimmer Helmar Görls Matthias Westerhausen 《Journal of organometallic chemistry》2011,696(1):216-5296
The calcium complex [(thf)4Ca(PPh2)2] (1) is a very effective catalyst for the hydrophosphanylation of substituted alkynes of the type R-CC-R (R = Me, Ph) yielding (E)-1,2-diphenyl-1-diphenylphosphanylethene (2a) and (Z)-1-phenyl-2-diphenylphosphanyl-1-propene (2b). The calcium-mediated hydrophosphanylation of butadiynes of the type R-CC-CC-R (R = Me, SiMe3, Ph, Mes, tBu) proceeds less selectively and diverse products are obtained such as 1,4-substituted 1,4-bis(diphenylphosphanyl)-1,3-butadienes (3), 1,4-diphenyl-1,2-bis(diphenylphosphanyl)-1,3-butadiene (4), and 1,4-di(tert-butyl)-1,4-bis(diphenylphosphanyl)buta-1,2-diene (5). Besides these regioisomers also several configuration isomers with respect to the C=C double bonds [(E)/(Z) isomerism] are obtained. A catalytic cycle can be formulated with the first addition of a Ca-P bond of the catalyst 1 to a CC triple bond always leading to the formation of an intermediate with the newly formed C-P bond in 1-position whereas the remaining phosphanido calcium fragment binds to the carbon in 2-position. The addition of a second diphenylphosphane is much faster and therefore, only two-fold hydrophosphanylated butadiynes are observed. Neither addition products with only one HPPh2 group nor those with more than two PPh2 substituents are obtained. 相似文献
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Vincent S. D. Voet Kamlesh Kumar Gerrit ten Brinke Katja Loos 《Macromolecular rapid communications》2015,36(19):1756-1760
The unique mechanical performance of nacre, the pearly internal layer of shells, is highly dependent on its complex morphology. Inspired by the structure of nacre, the fabrication of well‐ordered layered inorganic–organic nanohybrids is presented herein. This biomimetic approach includes the use of a block copolymer template, consisting of hydrophobic poly(vinylidene fluoride) (PVDF) lamellae covered with hydrophilic poly(methacrylic acid) (PMAA), to direct silica (SiO2) mineralization. The resulting PVDF/PMAA/SiO2 nanohybrid material resembles biogenic nacre with respect to its well‐ordered and layered nanostructure, alternating organic–inorganic phases, macromolecular template, and mild processing conditions.
59.
Maria Lasaosa Nathanaël Delmotte Christian G. Huber Katja Melchior Elmar Heinzle Andreas Tholey 《Analytical and bioanalytical chemistry》2009,393(4):1245-1256
The separation of complex peptide mixtures in shotgun proteome analysis using a 2D separation scheme encompassing reversed-phase
× ion-pair reversed-phase (IP-RP) liquid chromatography coupled online to electrospray ion trap mass spectrometry (MS) has
been shown earlier to be superior in terms of separation efficiency and technical robustness compared to the classically used
separation scheme encompassing strong cation exchange × IP-RP-chromatography in shotgun proteome analysis. In the present
study, this novel separation scheme was coupled offline to matrix-assisted laser desorption/ionization (MALDI) time-of-flight
(TOF)/TOF-MS for the analysis of the same sample, a tryptic digest of the cytosolic proteome of the bacterium Corynebacterium glutamicum. Compared to the earlier study, the MALDI-based platform led to a significantly increased number of peptides (7,416 vs. 2,709)
and proteins (1,208 vs. 468, without single peptide-based identifications), respectively. This represents the majority of
all predicted cytosolic proteins in C. glutamicum. The high proteome coverage, as well as the large number of low-abundant proteins identified with this improved analytical
platform, pave the way for new biological studies.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
60.