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1.
Alexander Pavlov Gonzalo D Garcia De Fernando Juan A Ordoez Lorenzo Hoz 《Journal of the science of food and agriculture》1994,64(2):141-143
The β-hydroxyacyl-CoA-dehydrogenase (HADH) activity of unfrozen and thawed frog legs was investigated. The enzyme was extracted by either immersing frog legs in phosphate buffer 0.1 M, pH 6.0 at 25°C for 15 min or pressing them between trichinoscopy glasses. The enzyme activity was assayed using acetoacetyl-CoA as substrate and measured spectrophotometrically at 340 nm. It was possible by both extraction methods to distinguish between thawed and unfrozen samples although when the juice was obtained by pressing the HADH activity of the dilution was ~ 1.5 times higher than that obtained by immersion. The HADH activity was significantly higher (P≤0·001) in frozen-thawed frogs than in unfrozen legs because during freezing there is a release of HADH. No significative differences were found in the HADH activity in samples frozen in the temperature range -10 to -196°C. HADH activity was not affected by the storage time in crushed ice up to 6 days. 相似文献
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A. V. Ikonnikov K. V. Marem’yanin S. V. Morozov V. I. Gavrilenko A. Yu. Pavlov N. V. Shchavruk R. A. Khabibullin R. R. Reznik G. E. Cirlin A. E. Zhukov Zh. I. Alferov 《Technical Physics Letters》2017,43(4):362-365
I–V and radiative characteristics of multilayer quantum-cascade GaAs/AlGaAs heterostructures with a double metal waveguide are investigated. The I–V characteristics typical of the quantum-cascade lasers are seen. The observed threshold-intensity growth and narrow radiation spectrum are characteristic of laser generation. The measured radiation frequency was found to be about 3 THz, which coincides with the calculated value. Thus, fully domestic terahertz quantum-cascade lasers are demonstrated for the first time. 相似文献
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Aleksandra Ochneva Yana Zorkina Olga Abramova Olga Pavlova Valeriya Ushakova Anna Morozova Eugene Zubkov Konstantin Pavlov Olga Gurina Vladimir Chekhonin 《International journal of molecular sciences》2022,23(22)
Mental disorders represent common brain diseases characterized by substantial impairments of social and cognitive functions. The neurobiological causes and mechanisms of psychopathologies still have not been definitively determined. Various forms of brain proteinopathies, which include a disruption of protein conformations and the formation of protein aggregates in brain tissues, may be a possible cause behind the development of psychiatric disorders. Proteinopathies are known to be the main cause of neurodegeneration, but much less attention is given to the role of protein impairments in psychiatric disorders’ pathogenesis, such as depression and schizophrenia. For this reason, the aim of this review was to discuss the potential contribution of protein illnesses in the development of psychopathologies. The first part of the review describes the possible mechanisms of disruption to protein folding and aggregation in the cell: endoplasmic reticulum stress, dysfunction of chaperone proteins, altered mitochondrial function, and impaired autophagy processes. The second part of the review addresses the known proteins whose aggregation in brain tissue has been observed in psychiatric disorders (amyloid, tau protein, α-synuclein, DISC-1, disbindin-1, CRMP1, SNAP25, TRIOBP, NPAS3, GluA1, FABP, and ankyrin-G). 相似文献
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The goal of this work is to analyze various classes of finite and total monomial orderings. The concept of monomial ordering plays the key role in the theory of Gröbner bases: every basis is determined by a certain ordering. At the same time, in order to define a Gröbner basis, it is not necessary to know ordering of all monomials. Instead, it is sufficient to know only a finite interval of the given ordering. We consider combinatorics of finite monomial orderings and its relationship with cells of a universal Gröbner basis. For every considered class of orderings (weakly admissible, convex, and admissible), an algorithm for enumerating finite orderings is discussed and combinatorial integer sequences are obtained. An algorithm for computing all minimal finite orderings for an arbitrary Gröbner basis that completely determine this basis is presented. The paper presents also an algorithm for computing an extended universal Gröbner basis for an arbitrary zero-dimensional ideal. 相似文献
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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
10.
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