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581.
Fabian St?gbauer Johanna Weigert Markus Neumeier Josef Wanninger Daniela Sporrer Markus Weber Andreas Sch?ffler Carlos Enrich Peta Wood Thomas Grewal Charalampos Aslanidis Christa Buechler 《Experimental & molecular medicine》2009,41(7):501-507
Adiponectin stimulates cholesterol efflux in macrophages and low adiponectin may in part contribute to disturbed reverse cholesterol transport in type 2 diabetes. Monocytes express high levels of annexin A6 that could inhibit cholesterol efflux and it was investigated whether the atheroprotective effects of adiponectin are accompanied by changes in annexin A6 levels. Adiponectin reduces annexin A6 protein whereas mRNA levels are not affected. Adiponectin-mediated activation of peroxisome proliferator-activated receptor α (PPARα) and AMP-activated protein kinase (AMPK) does not account for reduced annexin A6 expression. Further, fatty acids and lipopolysaccharide that are elevated in obesity do not influence annexin A6 protein levels. Annexin A6 in monocytes from overweight probands or type 2 diabetic patients is significantly elevated compared to monocytes of normal-weight controls. Monocytic annexin A6 positively correlates with body mass index and negatively with systemic adiponectin of the blood donors. Therefore, the current study demonstrates that adiponectin reduces annexin A6 in monocytes and thereby may enhance cholesterol efflux. In agreement with these in vitro finding an increase of monocytic annexin A6 in type 2 diabetes monocytes was observed. 相似文献
582.
Nathalie Lavignac Johanna L. Nicholls Paolo Ferruti Ruth Duncan 《Macromolecular bioscience》2009,9(5):480-487
Poly(amidoamine)s with amino pendant groups were prepared by hydrogen‐transfer polyaddition of primary and secondary amines to bis‐acrylamines. Dansyl cadaverine (DC) doxorubicin (Dox) were bound to the polymers via a cis‐aconityl spacer to give conjugates containing 3 µg of DC per mg of polymer and 28 to 35 µg of Dox per mg of polymer. Release of DC and Dox at physiological and acidic pH varied from 0 to 35% over 48 h and was pH dependent. Although the ISA1Dox conjugate (IC50 = 6 µg Dox · mL?1) presented similar toxicity as the parent polymer without Dox, ISA23Dox showed increased toxicity (IC50 = 10 µg Dox · mL?1). These results suggest that ISA23Dox is able to release biologically active Dox in vitro and that this conjugate might be suitable for further development.
583.
Neumair SC Knyrim JS Oeckler O Glaum R Kaindl R Stalder R Huppertz H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(46):13659-13670
The new borates Fe(II)(6)B(22)O(39)·H(2)O (colourless) and Co(II)(6)B(22)O(39)·H(2)O (dichroic: red/bluish) were synthesised under the high-pressure/high-temperature conditions of 6 GPa and 880 °C (Fe)/950 °C (Co) in a Walker-type multi-anvil apparatus. The compounds crystallise in the orthorhombic space group Pmn2(1) (Z=2) with the lattice parameters a=771.9(2), b=823.4(2), c=1768.0(4) pm, V=1.1237(4) nm(3), R(1)=0.0476, wR(2)=0.0902 (all data) for Fe(6)B(22)O(39)·H(2)O and a=770.1(2), b=817.6(2), c=1746.9(4) pm, V=1.0999(4) nm(3), R(1)=0.0513, wR(2)=0.0939 (all data) for Co(6)B(22)O(39)·H(2)O. The new structure type of M(6)B(22)O(39)·H(2)O (M=Fe, Co) is built up from corner-sharing BO(4) tetrahedra and BO(3) groups, the latter being distorted and close to BO(4) tetrahedra if additional oxygen atoms of the neighbouring BO(4) tetrahedra are considered in the coordination sphere. This situation can be regarded as an intermediate state in the formation of edge-sharing tetrahedra. The structure consists of corrugated multiple layers interconnected by BO(3)/BO(4) groups to form Z-shaped channels. Inside these channels, iron and cobalt show octahedral (M1, M3, M4, M5) and strongly distorted tetrahedral (M2, M6) coordination by oxygen atoms. Co(II)(6)B(22)O(39)·H(2)O is dichroic and the low symmetry of the chromophore [Co(II)O(4)] is reflected by the polarised absorption spectra (Δ(t)=4650 cm(-1), B=878 cm(-1)). 相似文献
584.
Different Synthesis Protocols for Co3O4–CeO2 Catalysts—Part 1: Influence on the Morphology on the Nanoscale 下载免费PDF全文
Dr. Jingxia Yang Liliana Lukashuk Dr. Johanna Akbarzadeh Dr. Michael Stöger‐Pollach Prof. Dr. Herwig Peterlik Dr. Karin Föttinger Prof. Dr. Günther Rupprechter Prof. Dr. Ulrich Schubert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):885-892
Co3O4‐modified CeO2 (Co/Ce 1:4) was prepared by a combination of sol–gel processing and solvothermal treatment. The distribution of Co was controlled by means of the synthesis protocol to yield three different morphologies, namely, Co3O4 nanoparticles located on the surface of CeO2 particles, coexistent Co3O4 and CeO2 nanoparticles, or Co oxide structures homogeneously distributed within CeO2. The effect of the different morphologies on the properties of Co3O4–CeO2 was investigated with regard to the crystallite phase(s), particle size, surface area, and catalytic activity for CO oxidation. The material with Co3O4 nanoparticles finely dispersed on the surface of CeO2 particles had the highest catalytic activity. 相似文献
585.
Light‐Triggered Capture and Release of DNA and Proteins by Host–Guest Binding and Electrostatic Interaction 下载免费PDF全文
Johanna Moratz Avik Samanta Dr. Jens Voskuhl Dr. Siva Krishna Mohan Nalluri Prof. Dr. Bart Jan Ravoo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3271-3277
The development of an effective and general delivery method that can be applied to a large variety of structurally diverse biomolecules remains a bottleneck in modern drug therapy. Herein, we present a supramolecular system for the dynamic trapping and light‐stimulated release of both DNA and proteins. Self‐assembled ternary complexes act as nanoscale carriers, comprising vesicles of amphiphilic cyclodextrin, the target biomolecules and linker molecules with an azobenzene unit and a charged functionality. The non‐covalent linker binds to the cyclodextrin by host–guest complexation with the azobenzene. Proteins or DNA are then bound to the functionalized vesicles through multivalent electrostatic attraction. The photoresponse of the host–guest complex allows a light‐induced switch from the multivalent state that can bind the biomolecules to the low‐affinity state of the free linker, thereby providing external control over the cargo release. The major advantage of this delivery approach is the wide variety of targets that can be addressed by multivalent electrostatic interaction, which we demonstrate on four types of DNA and six different proteins. 相似文献
586.
Emelie Westberg Ulla Hedebrant Johanna Haglund Tomas Alsberg Johan Eriksson Albrecht Seidel Margareta Törnqvist 《Analytical and bioanalytical chemistry》2014,406(5):1519-1530
Stable adducts to serum albumin (SA) from electrophilic and genotoxic compounds/metabolites can be used as biomarkers for quantification of the corresponding in vivo dose. In the present study, conditions for specific analysis of stable adducts to SA formed from carcinogenic polycyclic aromatic hydrocarbons (PAH) were evaluated in order to achieve a sensitive and reproducible quantitative method. Bulky adducts from diolepoxides (DE) of PAH, primarily DE of benzo[a]pyrene (BPDE) and also DE of dibenzo[a,l]pyrene (DBPDE) and dibenzo[a,h]anthracene (DBADE), were used as model compounds. The alkylated peptides obtained after enzymatic hydrolysis of human SA modified with the different PAHDE were principally PAHDE-His-Pro, PAHDE-His-Pro-Tyr and PAHDE-Lys. Alkaline hydrolysis under optimised conditions gave the BPDE-His as the single analyte of alkylated His, but also indicated degradation of this adduct. It was not possible to obtain the BPDE-His as one analyte from BPDE-alkylated SA through modifications of the enzymatic hydrolysis. The BPDE-His adduct was shown to be stable during the weak acidic conditions used in the isolation of SA. Enrichment by HPLC or SPE, but not butanol extraction, gave good recovery, using Protein LoBind tubes. A simple internal standard (IS) approach using SA modified with other PAHDE as IS was shown to be applicable. A robust analytical procedure based on digestion with pronase, enrichment by HPLC or SPE, and analysis with HPLC/MS-MS electrospray ionisation was achieved. A good reproducibility (coefficient of variation (CV) 11 %) was obtained, and the achieved limit of detection for the studied PAHDE, using standard instrumentation, was approximately 1 fmol adduct/mg SA analysing extract from 5 mg SA. Figure
An outline of the method for analysis of bulky SA-adducts. All steps/conditions were evaluated. 相似文献
587.
In this contribution, we recall and test a new methodology designed to identify the favorable reaction pathway between two reactants. Applied to the formation of the DNA guanine (G) –cytosine (C) pair, we successfully predict the best orientation between the base pairs held together by hydrogen bonds and leading to the formation of the typical Watson Crick structure of the GC pair. Beyond the global minimum, some local stationary points of the targeted pair are also clearly identified. 相似文献
588.
Wim Penninckx Desire L. Massart Johanna Smeyers-Verbeke 《Fresenius' Journal of Analytical Chemistry》1992,343(6):526-531
Summary A combination of 6 g palladium and 15 g magnesium nitrate is proposed as chemical modifier for lead determinations in biological materials and foodstuffs. The applicability of this modifier was investigated by the analysis of several types of samples, as compared to the classical NH4H2PO4 and Mg(NO3)2 modifier. Direct determinations of lead against aqueous standard solutions can be performed in 3-fold diluted urine, 2-fold diluted milk and 6-fold diluted blood, when the proposed modifier is added. A method for lead determinations in potatoes using the combined palladium and magnesium nitrate modifier, after a microwave acid digestion, is described. The optimum GFAAS pyrolysis temperature remains dependent on the matrix and should be determined for each type of sample. A wider linear range of the calibration curve is observed when the proposed Pd modifier is used. 相似文献
589.
Johanna Steen Margareta RamströmSophia Hober Jenny Ottosson 《Journal of chromatography. A》2009,1216(20):4457-4464
A completely automated procedure for the purification and desalting of proteins with a polyhistidine purification tag prior to mass spectrometry analysis is presented. The system is ideal for rapid quality control and optimization studies and it provides researchers with a straightforward, reliable tool for studies of recombinant proteins. Forty-eight samples can be prepared within 4.5 h and only small cultivation and buffer volumes are needed. In this proof of concept, 19,000–35,000 Da recombinant proteins from both crude and clarified cell lysates were successfully prepared for subsequent analysis by electrospray ionization and matrix-assisted laser desorption/ionization mass spectrometry as well as by gel electrophoresis. 相似文献
590.