scholarly journals Metmyoglobin Oxidation during Electron Transport Reactions in Mitochondria

1965 ◽  
Vol 48 (4) ◽  
pp. 685-698 ◽  
Author(s):  
Ann E. Kaplan-Bresler
Keyword(s):  
Hydrogen Peroxide ◽  
Electron Transport ◽  
Dissolved Oxygen ◽  
Heart Muscle ◽  
Absorption Peak ◽  
Experimental Conditions ◽  
Simultaneous Oxidation

Studies of the intracellular role of myoglobin were carried out by recording spectrophotometric changes in acid metmyoglobin and oxymyoglobin during electron transport reactions with mitochondria prepared from pigeon heart muscle by the method of Chance and Hagihara. The absorption peak of metmyoglobin at 409 mµ disappeared when substrate was added to normal or antimycin-inhibited preparations, and was replaced by a new maximum at 423 to 424 mµ, identified as due to the oxidation to ferrylmyoglobin. Further investigation revealed that the oxidation of metmyoglobin took place with the simultaneous oxidation of reduced flavoprotein. Hydrogen peroxide, formed by the reaction of reduced flavoprotein with oxygen, was considered to be the probable intermediate for the oxidation of metmyoglobin in experiments in which catalase was added as a competitor for the oxidant. When DPNH was added to the reaction mixture, the reductant acted to resynthesize the ferri-derivative by reaction with ferrylmyoglobin. Oxymyoglobin could not be used in place of metmyoglobin in these systems. Under the experimental conditions, oxymyoglobin dissociated when dissolved oxygen was depleted from the medium by enzyme oxidations; the resultant ferromyoglobin underwent oxidation to metmyoglobin.

Role of iron oxidation byproducts in the removal of phosphate from aqueous solution

RSC Advances ◽  
2016 ◽  
Vol 6 (2) ◽  
pp. 1627-1636 ◽  
Author(s):  
Nathalie Sleiman ◽  
Véronique Deluchat ◽  
Mahmoud Wazne ◽  
Alexandra Courtin ◽  
Zeinab Saad ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Dissolved Oxygen ◽  
Adsorption Capacity ◽  
Iron Oxidation ◽  
Synthesis And Characterization ◽  
Phosphate Adsorption ◽  
Dissolved Oxygen Concentration ◽  
Experimental Conditions

Synthesis and characterization of iron oxidation byproducts, in different experimental conditions (aging and dissolved oxygen concentration); study of their phosphate adsorption capacity.

scholarly journals Water Contaminated by Industrial Textile Dye: Study on Decolorization Process

Environments ◽  
2019 ◽  
Vol 6 (9) ◽  
pp. 101 ◽  
Author(s):  
Pierantonio De Luca ◽  
Paola Foglia ◽  
Carlo Siciliano ◽  
Jànos B. Nagy ◽  
Anastasia Macario
Keyword(s):  
Hydrogen Peroxide ◽  
Titanium Oxide ◽  
Sodium Carbonate ◽  
Dye Degradation ◽  
Reaction Rates ◽  
Textile Dye ◽  
Reactive Black 5 ◽  
Experimental Conditions ◽  
Textile Industries

This work aims to investigate possible interferences due to the presence of sodium carbonate on the photodegradation of the reactive Black 5 azoic dye, both in systems containing only titanium oxide and those containing titanium oxide and hydrogen peroxide. The role of hydrogen peroxide is explicitly treated. Sodium carbonate, in fact, is often present in the wastewater of textile industries as it is used in the fiber dyeing phases. The use of TiO2 nanoparticles is emphasized, and the possible danger is underlined. Each system was subjected to ultraviolet irradiation (UV) by varying the exposure time. After the photodegrading tests, the resulting solutions were analyzed by UV-vis spectrophotometry and High-Resolution Nuclear Magnetic Resonance to measure the residual concentrations of dye. The dye degradation curves and reaction rates for different UV exposure times were obtained and discussed as a function of the used additives. All the data are repeated three times, and they differ only by a maximum of 5%. The results indicated a reduction of about 50% of the initial concentration of Reactive Black 5 after 30 min under optimal experimental conditions. The NMR analysis indicated the formation of a series of aromatic structures that were generated by the UV-induced photochemical fragmentation of the original molecule.

scholarly journals Hydrogen peroxide discolors blood in the cavity of the hematoma under the nail and in the skin over the bruise

2020 ◽  
Vol 19 (2) ◽  
pp. 67-74
Author(s):  
A. L. Urakov ◽  
N. A. Urakova
Keyword(s):  
Hydrogen Peroxide ◽  
Venous Blood ◽  
Intradermal Injection ◽  
Alkaline Solutions ◽  
Experimental Conditions ◽  
Medical Standards ◽  
Subungual Hematoma ◽  
Clinical Conditions ◽  
Osmotic Activity

Purpose. Modern medical standards do not contain information about the urgent bleaching of nail hematomas and bruises. The aim of this work is developing of new ways and means for blood bleaching of the bruising and subungual hematomas for its immediate discoloration. Materials and methods. The peculiarities of hydrogen peroxide effect on blood color alteration in different environment have been studied in laboratory, by experiment and in clinical conditions. We studied the peroxide effect on liquid and dry venous blood in a Petri dishes, in bloody gauze bandages, on the surface of the skin, in hematoma under the nail in humans and in the skin over the bruise created by intradermal injection of pig blood. The studies take into account the role of local interaction such factors as the duration of interaction, the concentration of ingredients, local temperature, the value of alkaline and osmotic activity of the studied solutions. The results were recorded by color photo and video. Results. In laboratory and experimental conditions the red and blue blood as well as red, brown and/or blue stained tissues were shown to be urgently bleached by alkaline solutions of hydrogen peroxide. Hemoglobin was found to be the «dye» of blood-stained tissues. We listed the inventions to the intradermal bruising discoloration, subungual hematomas, and fresh and dried blood. The main ingredients of the inventions for intradermal and subungual hematomas bleaching are reported. The essence of the invented methods of skin and nail hematomas discoloration is presented. Conclusion. The alkaline solution of hydrogen peroxide can be used for emergency discoloration subungual hematoma, the skin in the area of bruise and the bandage stained with blood.

scholarly journals The application of statistical methods to indicators of triticale photosynthesis under chloride stress

2020 ◽  
Vol 61 (3) ◽  
pp. 105-111
Author(s):  
Viktor V. Ivanishchev ◽  
Keyword(s):  
Hydrogen Peroxide ◽  
Lipid Peroxidation ◽  
Cluster Analysis ◽  
Electron Transport ◽  
Carbonic Anhydrase ◽  
Correlation Coefficients ◽  
Analysis Method ◽  
Experimental Conditions ◽  
Close Relationship ◽  
Cluster Analysis Method

The paper presents the results of a study of the relationship between photosynthesis indicators of triticale shoots under conditions of short-term NaCl stress. For this, the principal component analysis (PCA) and cluster analysis were used. It was established that the characteristics of photosynthesis form three groups: (1) carbonic anhydrase and electron transport, (2) chlorophyll and carotenoids, (3) photosynthesis intensity. The correlation coefficients between the indicators are 0.85 and 0.97 for the first two groups, respectively. Using the cluster analysis method has led to similar results. Further analysis of the data with PCA for the characteristics of photosynthesis and oxidative stress showed that the indicators can also be combined into three groups: (1) stomatal conductivity, chlorine and sodium, (2) chlorophyll and carotenoids, (3) photosynthesis intensity and Rubisko activity. For physiological and biochemical parameters, the highest correlation coefficients were as follows: electron transport – lipid peroxidation (0.98), chlorophyll – carotenoids (0.97), carbonic anhydrase – LPO (0.86), carbonic anhydrase – electron transport (0.85), electron transport – hydrogen peroxide (0.63), LPO – hydrogen peroxide (0.62). The cluster analysis method suggests a close relationship between electron transport and the accumulation of hydrogen peroxide, carbonic anhydrase and lipid peroxidation. Based on the results obtained, conclusions are drawn about the close relationship between the activity of carbonic anhydrase and electron transport, and the magnitude of lipid peroxidation under experimental conditions, which, however, requires direct experimental evidence of such connections.

Site of Lysosome Production During Hepatic Injury

1969 ◽  
Vol 27 ◽  
pp. 348-349
Author(s):  
Nalin J. Unakar
Keyword(s):  
Electron Microscopy ◽  
Golgi Apparatus ◽  
Mouse Liver ◽  
Hepatic Injury ◽  
Close Approximation ◽  
Experimental Conditions ◽  
Toxic Injury

The increased number of lysosomes as well as the close approximation of lysosomes to the Golgi apparatus in tissue under variety of experimental conditions is commonly observed. These observations suggest Golgi involvement in lysosomal production. The role of the Golgi apparatus in the production of lysosomes in mouse liver was studied by electron microscopy of liver following toxic injury by CCI4.

The role of ligands in electron transport in nanocrystal solids

Nanoscale ◽  
2020 ◽  
Vol 12 (45) ◽  
pp. 23028-23035
Author(s):  
Artem R. Khabibullin ◽  
Alexander L. Efros ◽  
Steven C. Erwin
Keyword(s):  
Electron Transport ◽  
Theoretical Modeling

Theoretical modeling of wavefunction overlap in nanocrystal solids elucidates the important role played by ligands in electron transport.

The role of copper ions in hydrogen peroxide bleaching: Their origin, removal, and effect on pulp quality

TAPPI Journal ◽  
2012 ◽  
Vol 11 (7) ◽  
pp. 37-46 ◽  
Author(s):  
PEDRO E.G. LOUREIRO ◽  
SANDRINE DUARTE ◽  
DMITRY V. EVTUGUIN ◽  
M. GRAÇA V.S. CARVALHO
Keyword(s):  
Hydrogen Peroxide ◽  
Copper Ions ◽  
Peroxide Bleaching ◽  
Metals Removal ◽  
Peroxide Decomposition ◽  
Equipment Corrosion ◽  
And Performance ◽  
And Control ◽  
Main Effects

This study puts particular emphasis on the role of copper ions in the performance of hydrogen peroxide bleaching (P-stage). Owing to their variable levels across the bleaching line due to washing filtrates, bleaching reagents, and equipment corrosion, these ions can play a major role in hydrogen peroxide decomposition and be detrimental to polysaccharide integrity. In this study, a Cu-contaminated D0(EOP)D1 prebleached pulp was subjected to an acidic washing (A-stage) or chelation (Q-stage) before the alkaline P-stage. The objective was to understand the isolated and combined role of copper ions in peroxide bleaching performance. By applying an experimental design, it was possible to identify the main effects of the pretreatment variables on the extent of metals removal and performance of the P-stage. The acid treatment was unsuccessful in terms of complete copper removal, magnesium preservation, and control of hydrogen peroxide consumption in the following P-stage. Increasing reaction temperature and time of the acidic A-stage improved the brightness stability of the D0(EOP)D1AP bleached pulp. The optimum conditions for chelation pretreatment to maximize the brightness gains obtained in the subsequent P-stage with the lowest peroxide consumption were 0.4% diethylenetriaminepentaacetic acid (DTPA), 80ºC, and 4.5 pH.

The Affiliative Role of Empathy in Everyday Interpersonal Interactions

2019 ◽  
Author(s):  
Whitney R. Ringwald ◽  
Aidan G.C. Wright
Keyword(s):  
Individual Differences ◽  
Structural Equation ◽  
Community Sample ◽  
Empirical Support ◽  
Interpersonal Behavior ◽  
Equation Modeling ◽  
Experimental Conditions ◽  
Student Sample ◽  
Ecological Momentary

Empathy theoretically serves an affiliative interpersonal function by satisfying motives for intimacy and union with others. Accordingly, empathy is expected to vary depending on the situation. Inconsistent empirical support for empathy’s affiliative role may be due to methodology focused on individual differences in empathy or differences between controlled experimental conditions, which fail to capture its dynamic and interpersonal nature. To address these shortcomings, we used ecological momentary assessment to establish typical patterns of empathy across everyday interactions. Associations among empathy, affect, and interpersonal behavior of self and interaction partner were examined in a student sample (N=330), then replicated in a pre-registered community sample (N=279). Multi-level structural equation modeling was used to distinguish individual differences in empathy from interaction-level effects. Results show people are more empathetic during positively-valanced interactions with others perceived as warm and when expressing warmth. By confirming the typically affiliative role of empathy, existing research to the contrary can be best understood as exceptions to the norm.

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