Effect of carbon monoxide exposures on erythrocytic 2,3-DPG in rabbits

1976 ◽  
Vol 41 (5) ◽  
pp. 689-692 ◽  
Author(s):  
J. M. Ramsey ◽  
P. W. Casper
Keyword(s):  
Carbon Monoxide ◽  
Time Course ◽  
Exposure Period ◽  
Sampling Time ◽  
Quantitative Changes ◽  
2,3 Dpg

To determine if an exposure to lower levels of carbon monoxide (CO) produces quantitative changes in erythrocytic 2,3-diphosphoglycerate (2,3-DPG), eight rabbits were exposed to 100 ppm CO for 5 h resulting in approximately 20% carboxyhemoglobin (HbCO). 2,3-DPG was determined before exposure and immediately after exposure as well as every 3 h during the 24 h following exposure. To determine if intermittent CO exposures over a prolonged period of time affect 2,3-DPG, an additional 12 rabbits were exposed to 250 ppm CO for three intermittent periods totaling 300 min daily for 14 days (30% HbCO). 2,3-DPG was determined once per animal at the end of each day's exposure period. All animals served as their own controls in both experiments. Neither the results of the 24-h time course nor those of the 14-day time course showed significant differences in mean 2,3-DPG between controls and exposed animals at any sampling time. Apparently erythrocytic 2,3-DPG plays neither a compensating nor aggravating role in respect to the hypoxia induced by these levels of HbCO in the rabbit.

Postnatal regulation of 2,3-DPG in sheep erythrocytes

1983 ◽  
Vol 245 (3) ◽  
pp. H506-H512
Author(s):  
P. A. Mueggler ◽  
S. Carpenter ◽  
J. A. Black
Keyword(s):  
Fetal Sheep ◽  
L Cells ◽  
Erythrocyte Concentration ◽  
Glycolytic Control ◽  
Concentration Changes ◽  
Intracellular Activities ◽  
Quantitative Changes ◽  
Glycolytic Rate ◽  
2,3 Dpg

The erythrocyte 2,3-diphosphoglycerate (2,3-DPG) concentrations of sheep change markedly during the 1st mo following birth. From measurements of erythrocyte glycolytic enzymes and intermediate concentrations, we have identified the mechanism regulating erythrocyte 2,3-DPG in postnatal sheep. The postnatal changes in erythrocyte 2,3-DPG do not result from qualitative or quantitative changes in the intracellular activities of the Rapoport-Luebering shunt enzymes, 2,3-DPG mutase or 2,3-DPG phosphatase. The postnatal 2,3-DPG changes result from changes in the erythrocyte concentration of 1,3-DPG, which is controlled by other reactions in the glycolytic pathway. Neither changes in the glycolytic control enzymes (hexokinase, phosphofructokinase, and pyruvate kinase) nor changes in the intrinsic glycolytic rate can account for these 1,3-DPG concentration changes. 1,3-DPG concentrations are regulated by the in vivo glycolytic rate, which is controlled by the intracellular concentration of glucose, the glycolytic substrate. Glucose concentrations are 0.3 mmol/l cells in erythrocytes of fetal sheep (135-140 days gestational age), increase following birth to a peak of 3.8 mmol/l cells by the 1st wk of age, and then decline to the normal adult levels of 0.5 mmol/l cells by the end of the 1st mo.

scholarly journals A metabolomics characterisation of natural variation in the resistance of cassava to whitefly

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Laura Perez-Fons ◽  
Adriana Bohorquez-Chaux ◽  
Maria L. Irigoyen ◽  
Danielle C. Garceau ◽  
Kris Morreel ◽  
...  
Keyword(s):  
Time Course ◽  
Management Strategies ◽  
Resistance Mechanism ◽  
Central Africa ◽  
Susceptible Variety ◽  
Induced Response ◽  
Genotypic Differences ◽  
Germplasm Collections ◽  
Resistant Varieties ◽  
Quantitative Changes

Abstract Background Cassava whitefly outbreaks were initially reported in East and Central Africa cassava (Manihot esculenta Crantz) growing regions in the 1990’s and have now spread to other geographical locations, becoming a global pest severely affecting farmers and smallholder income. Whiteflies impact plant yield via feeding and vectoring cassava mosaic and brown streak viruses, making roots unsuitable for food or trading. Deployment of virus resistant varieties has had little impact on whitefly populations and therefore development of whitefly resistant varieties is also necessary as part of integrated pest management strategies. Suitable sources of whitefly resistance exist in germplasm collections that require further characterization to facilitate and assist breeding programs. Results In the present work, a hierarchical metabolomics approach has been employed to investigate the underlying biochemical mechanisms associated with whitefly resistance by comparing two naturally occurring accessions of cassava, one susceptible and one resistant to whitefly. Quantitative differences between genotypes detected at pre-infestation stages were consistently observed at each time point throughout the course of the whitefly infestation. This prevalent differential feature suggests that inherent genotypic differences override the response induced by the presence of whitefly and that they are directly linked with the phenotype observed. The most significant quantitative changes relating to whitefly susceptibility were linked to the phenylpropanoid super-pathway and its linked sub-pathways: monolignol, flavonoid and lignan biosynthesis. These findings suggest that the lignification process in the susceptible variety is less active, as the susceptible accession deposits less lignin and accumulates monolignol intermediates and derivatives thereof, differences that are maintained during the time-course of the infestation. Conclusions Resistance mechanism associated to the cassava whitefly-resistant accession ECU72 is an antixenosis strategy based on reinforcement of cell walls. Both resistant and susceptible accessions respond differently to whitefly attack at biochemical level, but the inherent metabolic differences are directly linked to the resistance phenotype rather than an induced response in the plant.

scholarly journals Changes in intermediate haemoglobins during autoxidation of haemoglobin

1981 ◽  
Vol 195 (2) ◽  
pp. 485-492 ◽  
Author(s):  
A Tomoda ◽  
Y Yoneyama ◽  
A Tsuji
Keyword(s):  
Isoelectric Focusing ◽  
Phosphate Buffer ◽  
Time Course ◽  
Inositol Hexaphosphate ◽  
Reaction Rate Constants ◽  
The Media ◽  
Beta 2 ◽  
Quantitative Changes ◽  
Ph Range ◽  
Experimental Values

The time course of haemoglobin autoxidation was studied under various conditions at 37 degrees C, and the changes in oxyhaemoglobin, intermediate haemoglobins and methaemoglobin during the reaction were analysed by isoelectric focusing on Ampholine/polyacrylamide-gel plates. Under various conditions (10 mM-phosphate buffer, 10 mM-phosphate buffer with 0.1 M-phosphate buffer, 10 mM-phosphate buffer with 0.1 M-NaCl, and 10 mM-phosphate buffer with 0.5 mM-inositol hexaphosphate; pH range 6.6-7.8 each case), the intermediate haemoglobins were found to be present as (alpha 2+ beta 3+)2 and (alpha 3+ beta 2+)2 valency hybrids from their characteristic positions on electrophoresis. Oxyhaemoglobin changed consecutively to (alpha 2+ beta 3+)2 and (alpha 3+ beta 2+)2, which were further oxidized to methaemoglobin, and the amounts of (alpha 3+beta 2+)2 were greater than those of (alpha 2+ beta 3+)2 during the reaction. The modes of the quantitative changes in oxyhaemoglobin, intermediate haemoglobins, and methaemoglobin were very similar in all the media used except for the inositol hexaphosphate addition. In the presence of inositol hexaphosphate, the autoxidation rates were considerably accelerated, and the modes of the changes in the haemoglobin derivatives were also considerably altered; the effects of this organic phosphate were maximal at acidic pH and minimal at alkaline pH. It was concluded that haemoglobin autoxidation proceeds by first-order kinetics through two paths: and (formula: see text). The reaction rate constants (k+1-k+4) best fitting all experimental values obtained by the isoelectric-focusing analysis were evaluated. By using these values, the mechanism of haemoglobin autoxidation is discussed.

Effect of Hydrogen on V-Type Pyrolysis Flame Synthesis of Carbon Nanotubes

2011 ◽  
Vol 221 ◽  
pp. 545-549
Author(s):  
Yuan Chao Liu ◽  
Bao Min Sun ◽  
Zhao Yong Ding
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Monoxide ◽  
Mass Flow ◽  
Experimental System ◽  
Catalyst Particle ◽  
Sampling Time ◽  
High Yield ◽  
Flame Synthesis ◽  
Novel Method ◽  
Synthesis Of Carbon Nanotubes

Synthesis of carbon nanotubes from V-type pyrolysis flame is a kind of novel method. It needs more simple equipments. The V-type pyrolysis flame experimental system is introduced. Carbon source is the carbon monoxide and heat source is from acetylene/air premixed flame. Pentacarbonyl iron is acted as catalyst. The sampling time was 5 minutes. This study aims to find the influence rule of hydrogen in synthesis of carbon nanotubes from the V-type pyrolysis flame. Carbon nanotubes with less impurity and high yield were captured successfully in the V-type pyrolysis flame. The diameter of carbon nanotubes was approximate between 10nm and 20nm, and its length was dozens of microns. Hydrogen played extremely important role in the flame synthesis of carbon nanotubes. The effect of hydrogen is to improve the pyrolysis of carbon monoxide and to decompose the carbide on the surface of catalyst particle. The flow or concentration of hydrogen will directly decide the surface roughness of carbon nanotubes from the pyrolysis flame. The carbon nanotubes with "carbon tumour" will appear when the relative flow of hydrogen in the reaction gases is too little. Not only the mass flow of hydrogen is important, but also the ratio of mass flow between carbon monoxide and hydrogen is very important according to the experiment results.

scholarly journals The time course of the heat effects in rapid chemical changes. Part II.—Some reactions of acids, bases, amino-acids and proteins

1930 ◽  
Vol 126 (802) ◽  
pp. 470-486 ◽  
Keyword(s):  
Carbon Monoxide ◽  
Chemical Reactions ◽  
Time Course ◽  
Carbonic Acid ◽  
Total Heat ◽  
Physical Factors ◽  
Single Experiment ◽  
Temperature Changes ◽  
Heat Effects ◽  
Acids And Bases

During the last 20 years the time relationships of the rapid heat changes in muscle and nerve have been the subject of exhaustive study, by Hill, Hartree, Meyerhof and many of their collaborators. The changes involved in such processes have turned out to be dependent both on physical factors and on the heat effects of a number of separate rapid chemical reactions. Hitherto, however, there seems to have been but little attempt, either by physical chemists or by physiologists, to study the time relationships involved in the heat effects of individual rapid chemical reactions themselves. Investigators, for instance, have contented themselves with measuring the total heat of such reactions, merely by mixing together in thermos flasks, or other suitable calorimeters, the reagents required, and by noting the temperature changes which ensue over the period subsequent to mixing. Since, as a rule, observations of this kind have to be extended over a period of some minutes in order to ensure that the heat liberated in the change is uniformly distributed through the calorimeter and its contents, no information is obtained as to whether the heat change under investigation is complete within say one minute or within the merest fraction of a second. Such information ought in certain cases to prove to be of great interest to chemistry, but of its importance in physiology when attempts are made to assess the rôle of separate chemical reactions in the rapid changes known to occur in muscle, nerve and blood there would seem to be no question. Recently a method has been worked out for this purpose, and a description of its experimental details and testings have been described fully above. It is sufficient to state here that the method has made it possible to mix together completely within a period of 0∙001 second or less the reagents, whose interaction it is desired to study, and to measure accurately the total heat evolved within a period of only 0·01 to 0·002 second after the reaction has been started by mixing the reagents. It has been shown that the total temperature change involved in such heat effects can be measured to an accuracy of 0·001°C., whilst in the case of “time” reactions in which the evolution or absorption heat takes place gradually over a period of 0·01 second or more the temperature changes between instants of time t 1 and t 2 can be determined almost to a further place of decimals, viz., 0·0001°C. to 0·0002°C. The present paper is of a preliminary kind and contains a description of the first applications of the method to the following rapid reactions: (α) the neutralisations of typical acids and bases (strong and weak); (β) the reactions of the simplest amino-acid, glycine, with acids, bases and buffers; (γ) the reactions of the blood proteins with acids and bases; and (δ) a single experiment on the reaction between carbon monoxide and hæmoglobin. It was to be anticipated that of the above reactions only those of carbonic acid with bases, of bicarbonate with acid, and of hæmoglobin with carbon monoxide, would fail to show completion of the heat change within 0·01 to 0·015 second. The experimental observations confirmed this expectation.

Time course of end-expired carbon monoxide concentration is important in studies of cigarette smoking

1987 ◽  
Vol 73 (5) ◽  
pp. 553-555 ◽  
Author(s):  
G. Woodman ◽  
D. M. Wintoniuk ◽  
R. G. Taylor ◽  
S. W. Clarke
Keyword(s):  
Carbon Monoxide ◽  
Cigarette Smoking ◽  
Time Course ◽  
Slow Phase ◽  
Fast Phase ◽  
Carbon Monoxide Concentration ◽  
The Mean

1. Fifteen asymptomatic habitual smokers each smoked one of their usual cigarettes, not having smoked for 2 h. End-expired carbon monoxide concentration (EECO) was measured with an Ecolyzer 2000 series analyser before smoking (pre-S value), 1 min after finishing smoking (post-S value) and then at intervals up to 1 h. 2. The mean EECO boost (increase) over all subjects declined biphasically after smoking, with an initial fast phase from 1 to 5 min, and then a slow phase from 5 to 60 min. EECO fell by as much in the first 5 min as in the next hour. 3. Post-S EECO was related to pre-S EECO (r = 0.89, P < 0.001), but EECO boost was not related to pre-S (r = 0.00). EECO boost was unaffected by the sampling manoeuvre. 4. EECO measurements in epidemiological and smoking studies should not be made for at least 5 min after a cigarette is finished

Synthesis of Carbon Nanotubes with Typical Structure from the Pyrolysis Flame

2011 ◽  
Vol 221 ◽  
pp. 99-103 ◽  
Author(s):  
Yuan Chao Liu ◽  
Na Na Zheng ◽  
Jing Dong Huang ◽  
Bao Min Sun
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Monoxide ◽  
Mass Production ◽  
Sampling Time ◽  
High Yield ◽  
Typical Structure ◽  
Catalyst Nanoparticles ◽  
Transmission Electron ◽  
Synthesis Of Carbon Nanotubes ◽  
Key Parameter

Synthesis of carbon nanotubes from V-type pyrolysis flame is a kind of new method. It has potential for carbon nanotubes preparation in mass production. Carbon monoxide was as carbon source and the acetylene/air premixed gas provides heat by combustion. Hydrogen/helium premixed gas acted as diluted and protection gas. Pentacarbonyl iron was served as catalyst. Carbon nanotubes with less impurity and high yield were captured successfully in the V-type pyrolysis flame. The diameter of carbon nanotubes was approximate between 10nm and 20nm, and its length was dozens of microns. The size of catalyst nanoparticles approximately was from 5 nm to 8nm in diameter. This study aims to examine the formation process of typical carbon nanotubes from pyrolysis flame and to characterize their morphology and structure. The morphology and structural of carbon nanotubes were characterized by scanning electron microscope and transmission electron microscopy respectively. Temperature was the key parameter in the process of synthesis carbon nanotubes. The concentration of catalyst had important influence on the synthesis of carbon nanotubes. Sampling time directly determined whether carbon nanotubes formation was completely. The carbon “dissolved-proliferation-separate out” theory can be used to explain that pentacarbonyl iron catalyses carbon monoxide in the process of carbon nanotube formation.

PIXE STUDIES ON POTASSIUM AND CALCIUM IN MOUSE BLOOD PLASMA AFTER TRANSPLANTATION OF EL-4 TUMOR CELLS

1995 ◽  
Vol 05 (04) ◽  
pp. 255-264 ◽  
Author(s):  
ITSURO TAMANOI ◽  
AKEMI NAKAMURA ◽  
KIYOFUSA HOSHIKAWA ◽  
MUTSUMI KACHI ◽  
KUNIO OOHASHI ◽  
...  
Keyword(s):  
Blood Plasma ◽  
Tumor Cells ◽  
Time Course ◽  
The Other ◽  
Histocompatibility Antigens ◽  
Mouse Blood ◽  
Major Histocompatibility Antigens ◽  
The Difference ◽  
Quantitative Changes ◽  
Pixe Method

The quantitative changes in the elements, amounts of Cl, K, Ca, in blood plasma were measured by PIXE method. The samples were obtained at appropriate intervals after transplantation of EL-4 tumor cells in three strains of mice, C57BL/6J (H-2b), C57BL/10J (abbreviation: B10; H-2b) and A/J (H-2a). Transplanted EL-4 tumor cells proliferated in both strains of C57BL/6J and B10. In A/J mice, transplanted EL-4 cells proliferated about 10 days and then were rejected completely by the immunological reaction according to the difference of major histocompatibility antigens. The amounts of Cl in plasma remained at similar level in the time course in any strains, but K fluctuated in C57BL/6J and B10, and less in A/J. On the other hand, Ca showed always higher values in C57BL/6J than other two strains of mice. In B10 mice, Ca increased just before death, but in A/J it decreased at the time of healing by rejection. These changes of Ca in the three strains of mice were related quantitatively 10 the hematocrit values of these strains of mice after transplantation of EL-4 cells.

scholarly journals Control of oxygen affinity of hemoglobin in K562 cells induced by hemin

Blood ◽  
1984 ◽  
Vol 63 (6) ◽  
pp. 1447-1452 ◽  
Author(s):  
Y Wu ◽  
A Dean ◽  
W Egan ◽  
AN Schechter
Keyword(s):  
Time Course ◽  
31P Nmr ◽  
Oxygen Affinity ◽  
K562 Cells ◽  
Hill Coefficient ◽  
Oxygen Dissociation ◽  
Oxygen Affinity Of Hemoglobin ◽  
Dissociation Curves ◽  
The Relationship ◽  
2,3 Dpg

Abstract The oxygen affinity of hemoglobin in K562 cells induced by hemin and the relationship between levels of 2,3-diphosphoglycerate (2,3-DPG) and hemoglobin have been investigated. Absorption spectra of induced cells indicate that the hemoglobin is oxygenated; oxygen dissociation curves are symmetric, with a P50 of 20 +/- 0.9 mm Hg, Hill coefficient of 2.5, and a normal temperature dependence. The intracellular pH measured by phosphorus 31 nuclear magnetic resonance (NMR) was 7.3. The amount of 2,3-DPG was determined by an enzymatic method and by 31P NMR. The level of 2,3-DPG in uninduced K562 cells, containing 0.5 pg of hemoglobin per cell, was low (5 +/- 0.5 mumole/10(8) cells), but increased to 64 +/- 5 mumole/10(8) cells upon induction of hemoglobin accumulation (to a final level of 20 pg hemoglobin/cell). For several experiments, there was a closely coordinated relationship between 2,3-DPG and hemoglobin levels, at about 1:1 stoichiometry of the two molecules. The time course of induction of hemoglobin, and of 2,3-DPG levels, are very similar; both processes are reversible. These data suggest that induction of hemoglobin synthesis in K562 cells by hemin results in hemoglobin-containing cells with normal oxygenation properties and that 2,3-DPG and hemoglobin levels are coordinately controlled in these cells. Elucidation of the mechanism of this effect should be of importance in understanding the erythroid-like differentiation of these cells.

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