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A. Pavlov G. D. García de Fernando O. Díaz M. Fernández D. López J. A. Ordóñez L. de la Hoz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1994,198(6):465-468
Changes in the -hydroxyacyl-CoA-dehydrogenase (HADH) activity of squid (Loligo vulgaris), mackerel (Scomber scombrus), tuna (Thunnus alalunga), sea bream (Pagellus centrodontus), sole (Solea solea), hake and small hake (Merluccius merluccius) meat due to freezing treatment at –10° C, –18° C, –35° C, –80° C or –196° C were investigated. With the exception of the small hake, the HADH activity of aqueous extracts from meat was significantly higher (p<0.0001) in all frozen/thawed fish species studied than in unfrozen animals because during freezing there was a release of HADH. HADH activity values of frozen/thawed squid, unfrozen mackerel, frozen/thawed and unfrozen sea bream and unfrozen hake were affected by the storage time in crushed ice.
Effekt des Gefrierens auf die-Hydroxyacyl-CoA-dehydrogenase (HADH)-Aktivität von Fischfleisch
Zusammenfassung Änderungen in der Aktivität der -Hydroxyacyl-CoA-dehydrogenase (HADH) im Fleisch von Tintenfisch, Makrele, Thunfisch, Seebrassen, Seezunge und Seehecht als Folge des Gefrierens bei –10 °C, –18 °C, –35 °C, –80 °C und –196 °C wurden untersucht. Mit Ausnahme kleiner Seehechte war die HADH-Aktivität wäßriger Extrakte des Fleisches bei allen gefrorenen und dann aufgetauten Fischen signifikant höher (p<0,0001) als bei ungefroren gelagerten Tieren. Dies ist Folge des Austrittes von HADH aus den Zellen während des Gefrierens. Die HADH-Aktivitäten von gefrorenem/aufgetautem Tintenfisch und Seebrassen sowie ungefrorenen Makrelen, Seebrassen und Seehechten wurden auch durch Lagern auf gestoßenem Eis beeinflußt.相似文献
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PM28A is a major intrinsic protein of the spinach leaf plasma membrane and the major phosphoprotein. Phosphorylation of PM28A is dependent in vivo on the apoplastic water potential and in vitro on submicromolar concentrations of Ca2+. Here, we demonstrate that PM28A is an aquaporin and that its water channel activity is regulated by phosphorylation. Wild-type and mutant forms of PM28A, in which putative phosphorylation sites had been knocked out, were expressed in Xenopus oocytes, and the resulting increase in osmotic water permeability was measured in the presence or absence of an inhibitor of protein kinases (K252a) or of an inhibitor of protein phosphatases (okadaic acid). The results indicate that the water channel activity of PM28A is regulated by phosphorylation of two serine residues, Ser-115 in the first cytoplasmic loop and Ser-274 in the C-terminal region. Labeling of spinach leaves with 32P-orthophosphate and subsequent sequencing of PM28A-derived peptides demonstrated that Ser-274 is phosphorylated in vivo, whereas phosphorylation of Ser-115, a residue conserved among all plant plasma membrane aquaporins, could not be demonstrated. This identifies Ser-274 of PM28A as the amino acid residue being phosphorylated in vivo in response to increasing apoplastic water potential and dephosphorylated in response to decreasing water potential. Taken together, our results suggest an active role for PM28A in maintaining cellular water balance. 相似文献
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N. P. Dubankova K. I. Kobrakov N. N. Pavlov T. E. Platova G. S. Stankevich V. A. Terent'eva E. M. Khitrova 《Fibre Chemistry》2003,35(1):12-16
The possibility of deliberately altering the biocidal and capillary properties of a fabric by combined treatment with solutions of metal salts and low-molecular-weight organic substances with special properties — dyeing, biocidal, etc., is demonstrated. 相似文献
27.
Tatyana Strekalova Dmitrii Pavlov Alexander Trofimov Daniel C. Anthony Andrei Svistunov Andrey Proshin Aleksei Umriukhin Alexei Lyundup Klaus-Peter Lesch Raymond Cespuglio 《International journal of molecular sciences》2022,23(4)
The phenomenon of individual variability in susceptibility/resilience to stress and depression, in which the hippocampus plays a pivotal role, is attracting increasing attention. We investigated the potential role of hippocampal cyclooxygenase-2 (COX-2), which regulates plasticity, neuroimmune function, and stress responses that are all linked to this risk dichotomy. We used a four-week-long chronic mild stress (CMS) paradigm, in which mice could be stratified according to their susceptibility/resilience to anhedonia, a key feature of depression, to investigate hippocampal expression of COX-2, a marker of microglial activation Iba-1, and the proliferation marker Ki67. Rat exposure, social defeat, restraints, and tail suspension were used as stressors. We compared the effects of treatment with either the selective COX-2 inhibitor celecoxib (30 mg/kg/day) or citalopram (15 mg/kg/day). For the celecoxib and vehicle-treated mice, the Porsolt test was used. Anhedonic (susceptible) but not non-anhedonic (resilient) animals exhibited elevated COX-2 mRNA levels, increased numbers of COX-2 and Iba-1-positive cells in the dentate gyrus and the CA1 area, and decreased numbers of Ki67-positive cells in the subgranular zone of the hippocampus. Drug treatment decreased the percentage of anhedonic mice, normalized swimming activity, reduced behavioral despair, and improved conditioned fear memory. Hippocampal over-expression of COX-2 is associated with susceptibility to stress-induced anhedonia, and its pharmacological inhibition with celecoxib has antidepressant effects that are similar in size to those of citalopram. 相似文献
28.
Radostin Stefanov Pavlov Juan B. Carda Castelló Vicente Blasco Marzá J. M. Hohembergerger 《Journal of the American Ceramic Society》2002,85(5):1197-1202
New high-stability red-shade ceramic pigments based on pyrochlore solid solutions Y2 Sn2− x Cr x O7−δ ( x = 0–1, 0 < δ= 0–1/2 x ) were developed employing conventional solid-state reaction synthesis. The relationship between their optical properties and microstructure was analyzed by X-ray diffractometry and ultraviolet–visible-light spectroscopy. Decomposition of the structure with formation of the perovskite YCrO3 observed for chromium substitutions x ≥ 5 was attributed mainly to high concentration of defects. The structural and optical parameters of the materials were found to correlate with the concentration of a species with higher oxidation state than Cr(III), such as Cr(IV) or Cr(V). 相似文献
29.
O. M. Pavleino V. A. Pavlov M. A. Pavleino 《Surface Engineering and Applied Electrochemistry》2010,46(5):440-446
This paper presents the computation results for the passage of a current through electrodes of various shapes. In particular,
cylindrically shaped contacts and rectangular current-carrying buses are considered. The effect of the electrode boundaries
and the location of the contact spots on the value of the contact resistance was estimated. It was shown when the contact
resistance can admittedly differ from the values found using the available analytical formulas. 相似文献
30.
O. S. Pavlov S. A. Karsakov S. Yu. Pavlov 《Theoretical Foundations of Chemical Engineering》2010,44(4):536-539
Economically efficient 2-methyl-2-butene production is an essential element of the promising isoprene manufacturing process using 2-methyl-2-butene epoxidation and the dehydration of the resulting epoxide. An efficient way of producing 2-methyl-2-butene is isopentane dehydrogenation followed by 2-methyl-2-butene recovery from the resulting C5 fraction by liquid-phase isomerization (preferably on sulfonic acid cation exchangers) and distillation. 相似文献