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21.
Hartmut Rehbein Horst Karl 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1985,180(5):373-378
Summary The extraction of fish muscle protein using SDS containing solubilization buffers was studied varying the time and the temperature of solubilization, as well as pH and SDS concentration of the buffer. At pH < 6 the myofbrillar proteins were incompletely solubilized; temperatures of 80-100 °C resulted in protein degradation observable in the SDS-PAGE.Samples of fish muscle containing high amounts of formaldehyde (50 mmoles FA/kg wet weight) could only be solubilised at 100 °C; on the other hand it was possible to solubilize cooked and/or canned products under mild conditions (2% SDS, 1% 2-ME, pH 8.9, shaking for 2 h at 60 °C).
Abbreviations FA formaldehyde - IEF isoelectric focusing - 2-ME 2-mercaptoethanol - PA polyacrylamide - PAGE polyacrylamide gel electrophoresis - pI isoelectric point - SDS sodium dodecyl sulfate - TMAO trimethylamine oxide - Tris Tris (hydroxymethyl)methylamine 相似文献
Solubilisierung von Fischmuskelproteinen durch Natriumdodecylsulfathaltige Puffer
Zusammenfassung Der Einfluß von Solubilisierungszeit und -temperatur, des pH-Wertes und der SDS-Konzentration des Solubilisierungspuffers auf die Extraktion von Fischmuskelproteinen wurde überprüft. Bei pH-Werten < 6 wurden die myofbrillären Proteine nur unvollständig gelöst; Solubilisierungstemperaturen von 80 bis 100 °C führten zu einem in der SDS-PAGE sichtbaren Proteinabbau. Fischmuskelproben mit hohem Formaldehydgehalt (50 mmole FA/kg Feuchtgewicht) ließen sich nur bei 100 °C vollständig solubilisieren; demgegenüber gelang die weitgehende Solubilisierung gegarter und/oder sterilisierter Produkte unter milden Bedingungen (2% SDS, 1% 2-ME, pH 8,9; 2stündiges Schütteln bei 60 °C).
Abbreviations FA formaldehyde - IEF isoelectric focusing - 2-ME 2-mercaptoethanol - PA polyacrylamide - PAGE polyacrylamide gel electrophoresis - pI isoelectric point - SDS sodium dodecyl sulfate - TMAO trimethylamine oxide - Tris Tris (hydroxymethyl)methylamine 相似文献
22.
Genome-Wide Investigation of Multifocal and Unifocal Prostate Cancer—Are They Genetically Different?
Chinyere Ibeawuchi Hartmut Schmidt Reinhard Voss Ulf Titze Mahmoud Abbas Joerg Neumann Elke Eltze Agnes Marije Hoogland Guido Jenster Burkhard Brandt Axel Semjonow 《International journal of molecular sciences》2013,14(6):11816-11829
Prostate cancer is widely observed to be biologically heterogeneous. Its heterogeneity is manifested histologically as multifocal prostate cancer, which is observed more frequently than unifocal prostate cancer. The clinical and prognostic significance of either focal cancer type is not fully established. To investigate prostate cancer heterogeneity, the genetic profiles of multifocal and unifocal prostate cancers were compared. Here, we report observations deduced from tumor-tumor comparison of copy number alteration data of both focal categories. Forty-one fresh frozen prostate cancer foci from 14 multifocal prostate cancers and eight unifocal prostate cancers were subjected to copy number variation analysis with the Affymetrix SNP 6.0 microarray tool. With the investigated cases, tumors obtained from a single prostate exhibited different genetic profiles of variable degrees. Further comparison identified no distinct genetic pattern or signatures specific to multifocal or unifocal prostate cancer. Our findings suggest that samples obtained from multiple sites of a single unifocal prostate cancer show as much genetic heterogeneity and variability as separate tumors obtained from a single multifocal prostate cancer. 相似文献
23.
Martin Schmücker Hartmut Schneider Thomas Mauer Bernd Clauß 《Journal of the American Ceramic Society》2005,88(2):488-490
Grain growth kinetics of mullite in laboratory-produced and commercial (3M-Nextel 720) alumino silicate fibers was analyzed in the temperature range between 1500° and 1700°C. The lab fibers consist of mullite plus traces of α-alumina, while the phase content of the commercial Nextel 720 fibers is about 60 wt% mullite plus 40 wt%α-alumina. The temperature-induced grain coarsening of mullite follows the empirical law D 1/ n − D 0 1/ n = kt . Two different temperature regimes can be distinguished with respect to the grain growth exponents: above 1600°C the growth exponent is ≈1/3, while below 1600°C the growth exponent of ≈1/12 is exceptionally low. Laboratory-produced and commercial fibers show almost identical mullite grain growth kinetics. 相似文献
24.
Dr. Holger Siebeneicher Dr. Arwed Cleve Dr. Hartmut Rehwinkel Dr. Roland Neuhaus Dr. Iring Heisler Dr. Thomas Müller Dr. Marcus Bauser Dr. Bernd Buchmann 《ChemMedChem》2016,11(20):2261-2271
Despite the long‐known fact that the facilitative glucose transporter GLUT1 is one of the key players safeguarding the increase in glucose consumption of many tumor entities even under conditions of normal oxygen supply (known as the Warburg effect), only few endeavors have been undertaken to find a GLUT1‐selective small‐molecule inhibitor. Because other transporters of the GLUT1 family are involved in crucial processes, these transporters should not be addressed by such an inhibitor. A high‐throughput screen against a library of ~3 million compounds was performed to find a small molecule with this challenging potency and selectivity profile. The N‐(1H‐pyrazol‐4‐yl)quinoline‐4‐carboxamides were identified as an excellent starting point for further compound optimization. After extensive structure–activity relationship explorations, single‐digit nanomolar inhibitors with a selectivity factor of >100 against GLUT2, GLUT3, and GLUT4 were obtained. The most promising compound, BAY‐876 [N4‐[1‐(4‐cyanobenzyl)‐5‐methyl‐3‐(trifluoromethyl)‐1H‐pyrazol‐4‐yl]‐7‐fluoroquinoline‐2,4‐dicarboxamide], showed good metabolic stability in vitro and high oral bioavailability in vivo. 相似文献
25.
Rajendra P. Maskey Ines Kock Mohamed Shaaban Iris Grün-Wollny Elisabeth Helmke Frank Mayer Irene Wagner-Döbler Hartmut Laatsch 《Polymer Bulletin》2002,49(2-3):87-93
Summary
A new group of low-molecular weight channel-forming oligo(hydroxybutyric acids) (cPHBs, 1 with n = 8–30; main component MW ≈ 1300 dalton) was isolated from microorganisms of different origin. Inclusion bodies were
electron-microscopically visible in cells in the state of autolysis, not in cells in the exponential phase of growth. cPHB
and high-molecular poly(l3-hydroxybutyric acid) (sPHB) is cleaved by phenylethylamine and forms the corresponding monomeric
hydroxybutyramide and – under drastic conditions, the crotylamide. One of these compounds, the 3-hydroxy-N-phenethyl-butyramide
(5), was isolated as a new natural product now.
Received: 28 March 2002/Revised version: 26 July 2002/ Accepted: 26 July 2002
RID="*"
ID="*"Marine Bakterien, XVII. XVI: R.P. Maskey, R.N. Asolkar, E. Helmke, and H. Laatsch, Chalcomycin B, a new antibiotic from
a marine Streptomyces sp. B7064. J. Antibiot., submitted 2002
Correspondence to Hartmut Laatsch, e-mail: hlaatsc@gwdg.de, Fax: +49-551-399660 相似文献
26.
Die Verfahren zur Aufbesserung der Brennstoffeigenschaften von Biomasse orientieren sich weitgehend an der Vergasung oder Verflüssigung von Braunkohle. Die hydrierende Umsetzung der in der Biomasse vorliegenden Biopolymere (Cellulosen, Lignin und Lignocellulosen) erfordern vor dem hydrierenden Angriff den chemischen Abbau der komplexen Biopolymer-Matrix. Man unterscheidet pyrolytische Verfahren (350 bis 500°C, drucklos) von den unter Druck durchgeführten hydrolytischen, solvolytischen und extraktiven Verfahren. Die relativ hohen Investitionskosten der Iysierenden Verfahren erfordern wegen der “Economy of scale” eine Mindestanlagengröße von mehreren hundert MW. Die Biomassevergasung und die darauf aufbauende Wasserstoff und Methanol-Erzeugung aus Biomasse sind vom Investitionsaufwand her gesehen auch für kleinere Anlagen geeignet. In nächster Zukunft dürfte sich die energetische Biomassenutzung allerdings auf die direkte Verbrennung in Biomasse-Heizkraftwerken bzw. die Vergasung und Verstromung des Gases in Brennstoffzellen beschränken. 相似文献
27.
Anindita Ghosh Susanta Banerjee De‐Yi Wang Hartmut Komber Brigitte Voit 《应用聚合物科学杂志》2012,123(5):2959-2967
Three new siloxane containing grafted copolyimides have been prepared by one‐pot solution imidization technique. The polymers are made by the reaction of 4,4′‐(4,4′‐isopropylidenediphenoxy)bis(phthalic anhydride) (BPADA) with commercially available diamine 4,4′‐oxydianiline (ODA) with variation of silicon containing diamine, namely 3,5‐diaminobenzoate terminated polydimethylsiloxane (DBPDMS), as a comonomer to 10, 20, and 30 wt %. The films of the polymers were prepared by casting the polymer solution in dichloromethane. The polymers have been well‐characterized by GPC, IR, and NMR techniques. Thermal stabilities and decomposition behavior of the copolyimides were studied by DSC and TGA. The water contact angle values of the films indicate hydrophobic nature of the polymers. Thermal, flame retardant, mechanical, and surface properties of these polymers have been compared with the homopolyimide and with polyimides where polysiloxane is incorporated in the main chain. DSC revealed melting of the grafted siloxane chain at sub‐ambient temperature and a glass transition corresponding to the main polymer chain above 200°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
28.
Respiratory tract infections are common, and when affecting the lower airways and lungs, can result in significant morbidity and mortality. There is an unfilled need for simple, non-invasive tools that can be used to screen for such infections at the clinical point of care. The electronic nose (eNose) is a novel technology that detects volatile organic compounds (VOCs). Early studies have shown that certain diseases and infections can result in characteristic changes in VOC profiles in the exhaled breath. This review summarizes current knowledge on breath analysis by the electronic nose and its potential for the detection of respiratory diseases with and without infection. 相似文献
29.
Mohammad Mangir Murshed Malik Šehović Michael Fischer Anatoliy Senyshyn Hartmut Schneider Thorsten M. Gesing 《Journal of the American Ceramic Society》2017,100(11):5259-5273
The evolution of metric parameters of 2:1 and 3:2 mullites have been measured between 4 K and 1320 K using neutron and X‐ray powder diffraction. Negative thermal expansion was observed at low temperature for the a‐cell parameter and consequently for the cell‐volume, which is more pronounced for 2:1 mullite than those for 3:2 mullite. Each parameter is simulated using Grüneisen first‐order approximation for the zero pressure equation of state at 0 K, where the vibrational energy was calculated using microscopic approach. While the b‐ and c‐cell parameters require only one Debye term, a second Debye spectrum with negative Grüneisen parameter was required to fit the a‐cell parameter as well as the cell volume. At 4 K, 300 K and 1320 K the model, respectively, calculates the volume thermal expansion coefficients of 0.09x10?6 K?1, 9x10?6 K?1, and 17.3x10?6 K?1 for 2:1 mullite, and 0.09x10?6 K?1, 8.7x10?6 K?1, and 17.3x10?6 K?1 for 3:2 mullite. Temperature‐dependent Raman spectra and phonon density of states hint for the possible microscopic sources of the cell contraction at low temperature. A simple polynomial approach is presented to calculate the elastic stiffness coefficients of the 3:2 mullite, which are not available from experiments. 相似文献
30.
Surface Binding of TOTAPOL Assists Structural Investigations of Amyloid Fibrils by Dynamic Nuclear Polarization NMR Spectroscopy 下载免费PDF全文
Dr. Madhu Nagaraj Dr. Trent W. Franks Siavash Saeidpour Dr. Tobias Schubeis Dr. Hartmut Oschkinat Dr. Christiane Ritter Dr. Barth‐Jan van Rossum 《Chembiochem : a European journal of chemical biology》2016,17(14):1308-1311
Dynamic nuclear polarization (DNP) NMR can enhance sensitivity but often comes at the price of a substantial loss of resolution. Two major factors affect spectral quality: low‐temperature heterogeneous line broadening and paramagnetic relaxation enhancement (PRE) effects. Investigations by NMR spectroscopy, isothermal titration calorimetry (ITC), and EPR revealed a new substantial affinity of TOTAPOL to amyloid surfaces, very similar to that shown by the fluorescent dye thioflavin‐T (ThT). As a consequence, DNP spectra with remarkably good resolution and still reasonable enhancement could be obtained at very low TOTAPOL concentrations, typically 400 times lower than commonly employed. These spectra yielded several long‐range constraints that were difficult to obtain without DNP. Our findings open up new strategies for structural studies with DNP NMR spectroscopy on amyloids that can bind the biradical with affinity similar to that shown towards ThT. 相似文献