33 research outputs found
High-pressure enzyme kinetics Lactate dehydrogenase in an optical cell that allows a reaction to be started under high pressure
AbstractA newly designed optical cell allows an enzyme reaction to be started under high pressure and makes it possible to begin measurement of the reaction rate after a βdead timeβ no longer than 1β2 s. This device was used to study the kinetics of lactate dehydrogenase reaction at 1 kbar. At this pressure lactate dehydrogenase from rabbit muscle exhibited a rapid deactivation in the presence of NADH if pyruvate was absent. After addition of pyruvate the reaction was initiated and proceeded at a constant rate, i.e., without loss of enzyme activity. It is suggested that pyruvate markedly increases the association constant of this tetrameric enzyme
Activation of a complex of ATPase with the natural protein inhibitor in submitochondrial particles
AbstractAlmost all ATPase molecules in submitochondrial particles, isolated from beef heart mitochondria in the presence of MgATP, are in an inactive complex with the natural protein inhibitor (IF1). In de-energized particles at high ionic strength a slow and irreversible ATPase activation is found to occur due to a dissociation of the enzyme-inhibitor complex. The pH-dependence of this process points out that deprotonation of IF1 molecule is an essential step in the dissociation of the complex. Zn2+ sharply accelerates ATPase activation, probably via binding with the deprotonated form of IF1. ATPase activation is completely prevented by MgATP, indicating the formation of a transient enzyme-inhibitor complex retaining ATPase activit
Glueball plus Pion Production in Photon-Photon Collisions.
We here compute the reaction
for various glueball candidates and their assumed quantum states, using a
non-relativistic gluon bound-state model for the glueball.Comment: To appear in Zeit. fur Phys. C; Plain Latex file, 16 pages; 5 figures
appended as a uuencoded postscript file
Twist-3 Distribute Amplitude of the Pion in QCD Sum Rules
We apply the background field method to calculate the moments of the pion
two-particles twist-3 distribution amplitude (DA) in QCD sum
rules. In this paper,we do not use the equation of motion for the quarks inside
the pion since they are not on shell and introduce a new parameter to
be determined. We get the parameter in this approach. If
assuming the expansion of in the series in Gegenbauer polynomials
, one can obtain its approximate expression which can be
determined by its first few moments.Comment: 12 pages, 3 figure
Uncoupling of oxidative phosphorylation and antioxidants affect fusion of primary human myoblasts in vitro
Reactive oxygen species are at the origin of muscular fatigue and atrophy. They are also linked to muscular dystrophies, a group of human genetic diseases. Several studies point to the benefits of application of antioxidants and uncouplers of oxidative phosphorylation to improve the functional activity of normal and pathological muscles. Other studies point to potential dangers of these compounds. Aim. To study the effect of mitochondria-targeted antioxidants and uncouplers of oxidative phosphorylation on muscle differentiation. Methods. Muscle differentiation was induced by serum starvation and monitored by troponin T staining. Results. the mitochondria-targeted uncoupler of oxidative phosphorylation C12TPP, but not the mitochondria-targeted antioxidant SkQ1, inhibit fusion of primary myoblasts upon their differentiation, but do not affect the synthesis of troponin T, a protein marker of muscle differentiation. Conclusion. The effect of C12TPP could be at least partially mediated by inhibition of reactive oxygen species (ROS) production since antioxidant N-acetylcysteine at high doses also inhibited differentiation of myoblasts.ΠΠΊΡΠΈΠ²Π½Ρ ΡΠΎΡΠΌΠΈ ΠΊΠΈΡΠ½Ρ (ΠΠ€Π) ΠΌΠΎΠΆΡΡΡ Π²ΠΈΠΊΠ»ΠΈΠΊΠ°ΡΠΈ ΠΌ'ΡΠ·ΠΎΠ²Ρ Π²ΡΠΎΠΌΡ Ρ Π°ΡΡΠΎΡΡΡ ΠΌ'ΡΠ·ΡΠ². ΠΠ€Π ΡΠ°ΠΊΠΎΠΆ ΠΏΠΎΠ²'ΡΠ·Π°Π½Ρ Π· ΠΌ'ΡΠ·ΠΎΠ²ΠΈΠΌΠΈ Π΄ΠΈΡΡΡΠΎΡΡΡ. ΠΠ΅Π·Π»ΡΡ Π΄ΠΎΡΠ»ΡΠ΄ΠΆΠ΅Π½Ρ Π²ΠΊΠ°Π·ΡΡ Π½Π° ΠΏΠΎΠ·ΠΈΡΠΈΠ²Π½ΠΈΠΉ Π²ΠΏΠ»ΠΈΠ² Π°Π½ΡΠΈΠΎΠΊΡΠΈΠ΄Π°Π½ΡΡΠ² Ρ ΡΠ°Π·ΠΎΠ±ΡΡΡΠ΅Π»Π΅ΠΉ ΠΎΠΊΠΈΡΠ½ΠΎΠ³ΠΎ ΡΠΎΡΡΠΎΡΠΈΠ»ΡΠ²Π°Π½Π½Ρ Π½Π° ΡΡΠ½ΠΊΡΡΠΎΠ½Π°Π»ΡΠ½Ρ Π°ΠΊΡΠΈΠ²Π½ΡΡΡΡ ΠΌ'ΡΠ·ΡΠ² Π² Π½ΠΎΡΠΌΡ ΡΠ° ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΡΡ. ΠΠ΅ΡΠ°. ΠΠΈΠ²ΡΠΈΡΠΈ Π²ΠΏΠ»ΠΈΠ² ΠΌΡΡΠΎΡ
ΠΎΠ½Π΄ΡΡΠ°Π»ΡΠ½ΠΎΡ-ΡΠΏΡΡΠΌΠΎΠ²Π°Π½ΠΈΡ
Π°Π½ΡΠΈΠΎΠΊΡΠΈΠ΄Π°Π½ΡΡΠ² Ρ ΡΠ°Π·ΠΎΠ±ΡΡΡΠ΅Π»Π΅ΠΉ ΠΎΠΊΠΈΡΠ½ΠΎΠ³ΠΎ ΡΠΎΡΡΠΎΡΠΈΠ»ΡΠ²Π°Π½Π½Ρ Π½Π° Π΄ΠΈΡΠ΅ΡΠ΅Π½ΡΡΡΠ²Π°Π½Π½Ρ ΠΏΠ΅ΡΠ²ΠΈΠ½Π½ΠΈΡ
ΠΌΡΠΎΠ±Π»Π°ΡΡΡΠ² Π»ΡΠ΄ΠΈΠ½ΠΈ. ΠΠ΅ΡΠΎΠ΄ΠΈ. Π Π΅Π·ΡΠ»ΡΡΠ°ΡΠΈ. ΠΌΡΡΠΎΡ
ΠΎΠ½Π΄ΡΡΠ°Π»ΡΠ½ΠΎΡ-ΡΠΏΡΡΠΌΠΎΠ²Π°Π½ΠΈΠΉ ΡΠ°Π·ΠΎΠ±ΡΠΈΡΠ΅Π»Ρ ΠΎΠΊΠΈΡΠ½ΠΎΠ³ΠΎ ΡΠΎΡΡΠΎΡΠΈΠ»ΡΠ²Π°Π½Π½Ρ C12TPP, Π°Π»Π΅ Π½Π΅ ΠΌΡΡΠΎΡ
ΠΎΠ½Π΄ΡΡΠ°Π»ΡΠ½ΠΎΡ-ΡΠΏΡΡΠΌΠΎΠ²Π°Π½ΠΈΠΉ Π°Π½ΡΠΈΠΎΠΊΡΠΈΠ΄Π°Π½Ρ SkQ1, ΠΏΡΠΈΠ³Π½ΡΡΡΡ Π·Π»ΠΈΡΡΡ ΠΌΡΠΎΠ±Π»Π°ΡΡΡΠ² ΠΏΡΠΈ Π΄ΠΈΡΠ΅ΡΠ΅Π½ΡΡΡΠ²Π°Π½Π½Ρ, ΠΏΡΠΈ ΡΡΠΎΠΌΡ Π½Π΅ Π²ΠΏΠ»ΠΈΠ²Π°ΡΡΠΈ Π½Π° Π΅ΠΊΡΠΏΡΠ΅ΡΡΡ ΡΡΠΎΠΏΠΎΠ½ΠΈΠ½Π° Π’, Π±ΡΠ»ΠΊΠΎΠ²ΠΎΠ³ΠΎ ΠΌΠ°ΡΠΊΠ΅ΡΠ° ΠΌ'ΡΠ·ΠΎΠ²ΠΎΡ Π΄ΠΈΡΠ΅ΡΠ΅Π½ΡΡΡΠ²Π°Π½Π½Ρ. ΠΠΈΡΠ½ΠΎΠ²ΠΊΠΈ. ΠΠΏΠ»ΠΈΠ² C12TPP ΠΌΠΎΠΆΠ΅ Π±ΡΡΠΈ ΡΠ°ΡΡΠΊΠΎΠ²ΠΎ Π²ΠΈΠΊΠ»ΠΈΠΊΠ°Π½ΠΎ ΠΏΡΠΈΠ³Π½ΡΡΠ΅Π½Π½ΡΠΌ ΠΠ€Π, ΡΠ°ΠΊ ΡΠΊ Π²ΠΈΡΠΎΠΊΡ ΠΊΠΎΠ½ΡΠ΅Π½ΡΡΠ°ΡΡΡ ΠΊΠ»Π°ΡΠΈΡΠ½ΠΎΠ³ΠΎ Π°Π½ΡΠΈΠΎΠΊΡΠΈΠ΄Π°Π½ΡΡ N-Π°ΡΠ΅ΡΠΈΠ»ΡΠΈΡΡΠ΅ΡΠ½Ρ ΡΠ°ΠΊΠΎΠΆ ΡΠ½Π³ΡΠ±ΡΠ²Π°Π»ΠΈ Π΄ΠΈΡΠ΅ΡΠ΅Π½ΡΡΡΠ²Π°Π½Π½Ρ ΠΌΡΠΎΠ±Π»Π°ΡΡΡΠ² Π»ΡΠ΄ΠΈΠ½ΠΈ.ΠΠΊΡΠΈΠ²Π½ΡΠ΅ ΡΠΎΡΠΌΡ ΠΊΠΈΡΠ»ΠΎΡΠΎΠ΄Π° (ΠΠ€Π) ΠΌΠΎΠ³ΡΡ Π²ΡΠ·ΡΠ²Π°ΡΡ ΠΌΡΡΠ΅ΡΠ½ΡΡ ΡΡΡΠ°Π»ΠΎΡΡΡ ΠΈ Π°ΡΡΠΎΡΠΈΡ ΠΌΡΡΡ. ΠΠ€Π ΡΠ°ΠΊΠΆΠ΅ ΡΠ²ΡΠ·Π°Π½Ρ Ρ ΠΌΡΡΠ΅ΡΠ½ΡΠΌΠΈ Π΄ΠΈΡΡΡΠΎΡΠΈΡΠΌΠΈ. ΠΠ½ΠΎΠΆΠ΅ΡΡΠ²ΠΎ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠΉ ΡΠΊΠ°Π·ΡΠ²Π°Π΅Ρ Π½Π° ΠΏΠΎΠ»ΠΎΠΆΠΈΡΠ΅Π»ΡΠ½ΠΎΠ΅ Π²Π»ΠΈΡΠ½ΠΈΠ΅ Π°Π½ΡΠΈΠΎΠΊΡΠΈΠ΄Π°Π½ΡΠΎΠ² ΠΈ ΡΠ°Π·ΠΎΠ±ΡΠΈΡΠ΅Π»Π΅ΠΉ ΠΎΠΊΠΈΡΠ»ΠΈΡΠ΅Π»ΡΠ½ΠΎΠ³ΠΎ ΡΠΎΡΡΠΎΡΠΈΠ»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ Π½Π° ΡΡΠ½ΠΊΡΠΈΠΎΠ½Π°Π»ΡΠ½ΡΡ Π°ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ ΠΌΡΡΡ Π² Π½ΠΎΡΠΌΠ΅ ΠΈ ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΠΈ. Π¦Π΅Π»Ρ. ΠΠ·ΡΡΠΈΡΡ Π²Π»ΠΈΡΠ½ΠΈΠ΅ ΠΌΠΈΡΠΎΡ
ΠΎΠ½Π΄ΡΠΈΠ°Π»ΡΠ½ΠΎ-Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½Π½ΡΡ
Π°Π½ΡΠΈΠΎΠΊΡΠΈΠ΄Π°Π½ΡΠΎΠ² ΠΈ ΡΠ°Π·ΠΎΠ±ΡΠΈΡΠ΅Π»Π΅ΠΉ ΠΎΠΊΠΈΡΠ»ΠΈΡΠ΅Π»ΡΠ½ΠΎΠ³ΠΎ ΡΠΎΡΡΠΎΡΠΈΠ»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ Π½Π° Π΄ΠΈΡΡΠ΅ΡΠ΅Π½ΡΠΈΡΠΎΠ²ΠΊΡ ΠΏΠ΅ΡΠ²ΠΈΡΠ½ΡΡ
ΠΌΠΈΠΎΠ±Π»Π°ΡΡΠΎΠ² ΡΠ΅Π»ΠΎΠ²Π΅ΠΊΠ°. ΠΠ΅ΡΠΎΠ΄Ρ. Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ. ΠΌΠΈΡΠΎΡ
ΠΎΠ½Π΄ΡΠΈΠ°Π»ΡΠ½ΠΎ-Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½Π½ΡΠΉ ΡΠ°Π·ΠΎΠ±ΡΠΈΡΠ΅Π»Ρ ΠΎΠΊΠΈΡΠ»ΠΈΡΠ΅Π»ΡΠ½ΠΎΠ³ΠΎ ΡΠΎΡΡΠΎΡΠΈΠ»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ C12TPP, Π½ΠΎ Π½Π΅ ΠΌΠΈΡΠΎΡ
ΠΎΠ½Π΄ΡΠΈΠ°Π»ΡΠ½ΠΎ-Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½Π½ΡΠΉ Π°Π½ΡΠΈΠΎΠΊΡΠΈΠ΄Π°Π½Ρ SkQ1, ΠΈΠ½Π³ΠΈΠ±ΠΈΡΡΠ΅Ρ ΡΠ»ΠΈΡΠ½ΠΈΠ΅ ΠΌΠΈΠΎΠ±Π»Π°ΡΡΠΎΠ² ΠΏΡΠΈ Π΄ΠΈΡΡΠ΅ΡΠ΅Π½ΡΠΈΡΠΎΠ²ΠΊΠ΅, ΠΏΡΠΈ ΡΡΠΎΠΌ Π½Π΅ Π²Π»ΠΈΡΡ Π½Π° ΡΠΊΡΠΏΡΠ΅ΡΡΠΈΡ ΡΡΠΎΠΏΠΎΠ½ΠΈΠ½Π° Π’, Π±Π΅Π»ΠΊΠΎΠ²ΠΎΠ³ΠΎ ΠΌΠ°ΡΠΊΠ΅ΡΠ° ΠΌΡΡΠ΅ΡΠ½ΠΎΠΉ Π΄ΠΈΡΡΠ΅ΡΠ΅Π½ΡΠΈΡΠΎΠ²ΠΊΠΈ. ΠΡΠ²ΠΎΠ΄Ρ. ΠΠ»ΠΈΡΠ½ΠΈΠ΅ C12TPP ΠΌΠΎΠΆΠ΅Ρ Π±ΡΡΡ ΡΠ°ΡΡΠΈΡΠ½ΠΎ Π²ΡΠ·Π²Π°Π½ΠΎ ΠΈΠ½Π³ΠΈΠ±ΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ ΠΠ€Π, ΡΠ°ΠΊ ΠΊΠ°ΠΊ Π²ΡΡΠΎΠΊΠΈΠ΅ ΠΊΠΎΠ½ΡΠ΅Π½ΡΡΠ°ΡΠΈΠΈ ΠΊΠ»Π°ΡΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π°Π½ΡΠΈΠΎΠΊΡΠΈΠ΄Π°Π½ΡΠ° N-Π°ΡΠ΅ΡΠΈΠ»ΡΠΈΡΡΠ΅ΠΈΠ½Π° ΡΠ°ΠΊΠΆΠ΅ ΠΈΠ½Π³ΠΈΠ±ΠΈΡΠΎΠ²Π°Π»ΠΈ Π΄ΠΈΡΡΠ΅ΡΠ΅Π½ΡΠΈΡΠΎΠ²ΠΊΡ ΠΌΠΈΠΎΠ±Π»Π°ΡΡΠΎΠ² ΡΠ΅Π»ΠΎΠ²Π΅ΠΊΠ°
Mitochondrial ATP hydrolysis and ATP depletion in thymocytes and Ehrlich ascites carcinoma cells
Prolonged lipid oxidation after photodynamic treatment. Study with oxidation-sensitive probe C11-BODIPY581/591
AbstractPhotodynamic treatment (PDT) is an emerging procedure for the therapy of cancer, based on photosensitizers, compounds that generate highly reactive oxygen species on illumination with visible light. Photodynamic peroxidation of cellular lipids is a consequence of PDT associated with cytolethality. We used chloromethyl dichlorodihydrofluorescein diacetate and a novel fluorescent ratiometric oxidation-sensitive probe, C11-BODIPY581/591 (C11-BO), which reports on lipid peroxidation, for visualizing oxidative stress in cells subjected to PDT with a phthalocyanine photosensitizer Pc4. With C11-BO loaded into the cells before or immediately after PDT, we observed a prolonged oxidation, which continued up to 30min after illumination. In contrast, H2O2 caused oxidation of C11-BO only when the cells were in direct contact with H2O2. PDT-induced oxidative stress was most pronounced in vesicular perinuclear organelles, most likely photodamaged lysosomes. We hypothesize that the lysosomal localization of the prolonged oxidative stress is a consequence of the presence of redox-active iron in lysosomes. In conclusion, we have found that oxidative stress induced in cells by PDT differs from one induced by H2O2 in respect of induction of prolonged oxidation of lipids