scholarly journals Iron release from ferritin and its sensitivity to superoxide ions differs among vertebrates

1994 ◽  
Vol 301 (2) ◽  
pp. 385-389 ◽  
Author(s):  
L R Harris ◽  
M H Cake ◽  
D J Macey
Keyword(s):  
Superoxide Dismutase ◽  
Initial Rate ◽  
The Other ◽  
High Rate ◽  
Iron Release ◽  
Iron Protein ◽  
Liver Ferritin ◽  
Comparable Magnitude ◽  
Generating System ◽  
Subunit Size

The influence of the superoxide-generating system, xanthine oxidase, on the release of iron from various vertebrate ferritins was determined both in the presence and absence of superoxide dismutase. The initial rate of iron release in the presence of this system was higher for ferritins from human, trout and rat liver than for those from lamprey liver and horse spleen. The proportion of this iron release that was superoxide-dependent in the case of rat, human and trout ferritins was 92, 86 and 84% respectively, whereas no such superoxide-dependent iron release occurred from the ferritins of lamprey liver and horse spleen. On the other hand, the rate of superoxide-independent iron release was of comparable magnitude for all of the species examined. The rate of superoxide-dependent iron release was related neither to the iron: protein ratios nor to the subunit size of the ferritins. However, it is significant that the ferritins with a high rate of superoxide-dependent iron release came from tissues known to be susceptible to iron damage. It is thus proposed that the resistance of lamprey liver ferritin to the mobilization of iron by superoxide ions accounts in part for the tolerance of the lamprey liver to high iron loads.

scholarly journals Sugars and Respiration Profiles in Asparagus Spears and Changes during Storage

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 823F-823
Author(s):  
Silvanda Silva ◽  
Sven Verlinden ◽  
Robert Herner ◽  
Randolph Beaudry
Keyword(s):  
Respiration Rate ◽  
Initial Rate ◽  
The Other ◽  
Asparagus Officinalis ◽  
High Rate ◽  
Sucrose Content ◽  
Time Intervals ◽  
Respiration Rates

Base-to-tip profiles of sucrose, glucose, fructose, and respiration rate were measured for asparagus (Asparagus officinalis L.) spears stored at 0C. Fructose content was ≈3-fold and 4-fold higher than glucose and sucrose, respectively. The highest level of fructose was found in the base and was ≈15-fold higher than the tip. The changes in asparagus metabolism were characterized by loss of sucrose and a high rate of respiration within the first hours after harvest. Sucrose was more rapidly lost than the other sugars during this period. The respiration rate was measured along the length of intact spears at 0.5, 1, 2, and 3 h after harvest. Subsequent measurements were taken after larger time intervals for 23 days. The respiration rate declined rapidly to ≈60% of the initial rate within 12 h, decreasing more slowly thereafter. Initially, the respiration rate of the tip was about four times that of the base, but, after 23 days, the respiration rate of the tip was only twice that of the base. Sucrose content and respiration rates were closely correlated.

scholarly journals First Report of blaNDM-1 Bearing IncX3 Plasmid in Clinically Isolated ST11 Klebsiella pneumoniae from Pakistan

2021 ◽  
Vol 9 (5) ◽  
pp. 951
Author(s):  
Hazrat Bilal ◽  
Gaojian Zhang ◽  
Tayyab Rehman ◽  
Jianxion Han ◽  
Sabir Khan ◽  
...  
Keyword(s):  
Sequence Type ◽  
The Other ◽  
High Rate ◽  
Antibiotics Resistance ◽  
New Delhi ◽  
Molecular Type ◽  
Plasmid Analysis ◽  
First Time ◽  
Encoding Genes ◽  
Sequence Types

The New Delhi Metallo-β-lactamase (NDM) is among the most threatening forms of carbapenemases produced by K. pneumoniae, well-known to cause severe worldwide infections. The molecular epidemiology of blaNDM-1-harboring K. pneumoniae is not well elucidated in Pakistan. Herein, we aim to determine the antibiotics-resistance profile, genes type, molecular type, and plasmid analysis of 125 clinically isolated K. pneumoniae strains from urine samples during July 2018 to January 2019 in Pakistan. A total of 34 (27.2%) K. pneumoniae isolates were carbapenemases producers, and 23 (18.4%) harbored the blaNDM-1 gene. The other carbapenemases encoding genes, i.e., blaIMP-1 (7.2%), blaVIM-1 (3.2%), and blaOXA-48 (2.4%) were also detected. The Multi Locus Sequence Typing (MLST) results revealed that all blaNDM-1-harboring isolates were ST11. The other sequence types detected were ST1, ST37, and ST105. The cluster analysis of Xbal Pulsed Field Gel Electrophoresis (PFGE) revealed variation amongst the clusters of the identical sequence type isolates. The blaNDM-1 gene in all of the isolates was located on a 45-kb IncX3 plasmid, successfully transconjugated. For the first time, blaNDM-1-bearing IncX3 plasmids were identified from Pakistan, and this might be a new primary vehicle for disseminating blaNDM-1 in Enterobacteriaceae as it has a high rate of transferability.

A Multiregion Model with Capital Accumulation and Endogenous Amenities

2007 ◽  
Vol 39 (9) ◽  
pp. 2248-2270 ◽  
Author(s):  
Wei-Bin Zhang
Keyword(s):  
Capital Accumulation ◽  
Comparative Statics ◽  
The Other ◽  
High Rate ◽  
Unique Equilibrium ◽  
Economic Activities ◽  
Technological Differences ◽  
National Output ◽  
Simulation Results ◽  
Wage Disparities

The author develops a multiregional growth model with endogenous amenity and capital accumulation for any number of regions. The simulation results demonstrate that the national dynamics have a unique equilibrium. Comparative statics analysis shows that, if environmental improvement occurs in the technologically advanced (less advanced) region, the national output rises (falls). As a region improves its technology, the other two regions' aggregated output levels fall—not only in relative, but also in absolute, terms. This implies that if any region has a high rate of technological change and the other regions remain technologically stationary, then economic activities will tend to be concentrated in the technologically advancing region. It is also shown that technological differences appear to play only a small role in accounting for spatial wage disparities and endowments.

Voluntary intake, digestibility and rate of passage of a hay and a silage fed to horses and to cattle

1995 ◽  
Vol 1995 ◽  
pp. 164-164
Author(s):  
B. McLean ◽  
A. Afzalzadeh ◽  
L. Bates ◽  
R.W. Mayes ◽  
F.D.DeB. Hovell
Keyword(s):  
Sugar Beet ◽  
Microbial Degradation ◽  
Poor Quality ◽  
The Other ◽  
Alternative Strategy ◽  
High Rate ◽  
Beet Pulp ◽  
Voluntary Intake ◽  
Hind Gut ◽  
Adequate Nutrient

It is well established that the intake and digestibility of roughages by ruminants is positively correlated with rate of passage (ARC, 1980), presumably to enable as complete a microbial degradation of the poorer roughages as possible. On the other hand hind gut fermenters such as horses have been thought to have adopted the alternative strategy of using a high rate of passage to ‘cream’ off the rapidly degradable material of poor quality roughages so as to maintain adequate nutrient intakes. Surprisingly, there are remarkably few actual comparisons between ruminants and hindgut fermenters in the literature. Traditionally dried roughages (hay) and cereal and ‘by-product concentrates’ have been used as horse feeds (grains, brans sugar beet pulp). Recently there has been more interest in the use of silages with horses (eg Smoulders and Hobiers, 1988). However the information as to the utilisation of silages by horses is limited.

scholarly journals Simulation of the electron-paramagnetic-resonance spectrum of the iron-protein of nitrogenase. A prediction of the existence of a second paramagnetic centre

1978 ◽  
Vol 175 (3) ◽  
pp. 955-957 ◽  
Author(s):  
D J Lowe
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Electron Paramagnetic Resonance Spectrum ◽  
Complex Formation ◽  
Resonance Spectrum ◽  
The Other ◽  
Paramagnetic Centre ◽  
Paramagnetic Resonance ◽  
Iron Protein ◽  
Integrated Intensities ◽  
Electron Paramagnetic

The e.p.r. spectra of the Fe-proteins of nitrogenase from all sources studied have unusual features in that they have very anisotropic linewidths and low integrated intensities. These characteristics can be explained by assuming that one of the two electrons accepted by these proteins is located at a rapidly relaxing paramagnetic centre that is unobservable by e.p.r., but causes anisotropic broadening of the e.p.r. signal of the other electron. Complex-formation between Fe-proteins and MgATP is described in terms of a 50-60 degrees rotation of the e.p.r.-observable centre.

Cellular Sites of Hepatic Ferritin Activation and Inactivation

1957 ◽  
Vol 192 (1) ◽  
pp. 181-185 ◽  
Author(s):  
Silvio Baez ◽  
S. G. Srikantia ◽  
Anne Carleton
Keyword(s):  
Traumatic Shock ◽  
The Other ◽  
Anaerobic Incubation ◽  
Other Hand ◽  
Liver Ferritin ◽  
Parenchymal Cells

Studies with viable reticulo-endothelial (RE) and parenchymal cells separated from the liver show that the parenchymal cells contain most of the liver ferritin. This ferritin is vasoinert, and anaerobic incubation of the parenchymal cells does not release it in vasoactive form. Aerobic parenchymal cells readily inactivate exogenous vasoactive ferritin. Parenchymal cells isolated from the liver of normal rats subjected to traumatic shock contain vasoactive ferritin and have lost their ferritin inactivating capacity, whereas those from resistant rats subjected to the same trauma contain only vasoinert ferritin and are still able to inactivate added ferritin. On the other hand, RE cells contain smaller amounts of vasoinert ferritin but readily release it in vasoactive form on anaerobic incubation. RE cells are not able to inactivate exogenous ferritin. When a small amount of a vasoinert, clear extract, prepared from homogenized RE cells, is added to parenchymal cells during anaerobic incubation, the parenchymal cells release their ferritin in vasoactive form. The ‘activator’ obtained from the RE cells has not been identified.

Oxidative damage of canine erythrocytes after treatment with non-steroidal anti-inflammatory drugs

2021 ◽  
Vol 49 (06) ◽  
pp. 407-413
Author(s):  
Julia Lieser ◽  
Claudia Schwedes ◽  
Maria Walter ◽  
Judith Langenstein ◽  
Andreas Moritz ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Oxidative Damage ◽  
Hemoglobin Concentration ◽  
The Other ◽  
Severe Illness ◽  
Heinz Bodies ◽  
Significant Difference ◽  
Gluthathione Peroxidase ◽  
Inflammatory Drugs ◽  
Anti Inflammatory

Abstract Objective To investigate oxidative erythrocyte damage in dogs treated with different non-steroidal anti-inflammatory drugs. Material and methods Case-controlled prospective observational study using blood obtained from dogs presenting for lameness examinations or standard surgical procedures to a private referral clinic. Sampling was performed from April 2018 to July 2019. Groups comprised dogs receiving either metamizole (dipyrone) (22 dogs), carprofen (20 dogs) or meloxicam (20 dogs) for a minimum of 10 days. Dogs with gastrointestinal hemorrhage were excluded from the study. A complete hematological, as well as a basic biochemical profile were performed in every dog. Pappenheim stained blood smears were evaluated for eccentrocytes and brilliant cresyl blue stained smears for Heinz bodies. EDTA blood was frozen at –80°C immediately after sampling for measurement of superoxide dismutase and gluthathione peroxidase activity at an external laboratory. Hemoglobin concentration, superoxide dismutase and gluthathione peroxidase activities, reticulocyte count, eccentrocyte and Heinz body numbers were determined prospectively as key parameters for further statistical assessment with Kruskal-Wallis test and Dunn’s multiple comparisons test. Results Dogs receiving metamizole showed a significant increase in eccentrocyte (median 14.5/500 cells vs. 0/500 cells in the other groups, p < 0.0001) and reticulocyte number (median 191.4 × 109/l vs. 31.6–37.9 × 109/l, p < 0.0001) and a significant decrease in hemoglobin concentration (median 8.4 mmol/l vs. 10.1–10.5 mmol/l, p < 0.0003). No significant difference in superoxide dismutase and gluthathione peroxidase activities was observed between dogs receiving metamizole and the other groups. Heinz bodies were not found in any of the dogs. Conclusion Treatment with metamizole for 10 or more days resulted in decreased hemoglobin concentration, eccentrocytosis and reticulocytosis in dogs in this study. This might be a sign of increased oxidative damage caused by this drug. Clinical significance Prolonged metamizole therapy should be evaluated critically in patients already affected by severe illness or underlying anaemia.

scholarly journals An Investigation into Sub-Critical Choke Flow Performance in High Rate Gas Condensate Wells

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3992
Author(s):  
Nasriani ◽  
Khan ◽  
Graham ◽  
Ndlovu ◽  
Nasriani ◽  
...  
Keyword(s):  
Flow Rate ◽  
Parameter Variation ◽  
Gas Condensate ◽  
The Other ◽  
High Rate ◽  
Production Data ◽  
Empirical Correlations ◽  
New Correlation ◽  
Production Wells ◽  
Data Points

There have been some correlations in the literature to predict the gas and liquid flow rate through wellhead chokes under subcritical flow conditions. The majority of these empirical correlations have been developed based on limited production data sets that were collected from a small number of fields. Therefore, these correlations are valid within the parameter variation ranges of those fields. If such correlations are used elsewhere for the prediction of the subcritical choke flow performance of the other fields, significant errors will occur. Additionally, there are only a few empirical correlations for sub-critical choke flow performance in high rate gas condensate wells. These led the authors to develop a new empirical correlation based on a wider production data set from different gas condensate fields in the world; 234 production data points were collected from a large number of production wells in twenty different gas condensate fields with diverse reservoir conditions and different production histories. A non-linear regression analysis method was applied to their production. The new correlation was validated with a new set of data points from some other production wells to confirm the accuracy of the established correlation. The results show that the new correlation had minimal errors and predicted the gas flow rate more accurately than the other three existing models over a wider range of parameter variation ranges.

scholarly journals Making Acoustic Computer Music: The Rumentarium project

2013 ◽  
Vol 18 (3) ◽  
pp. 242-254 ◽  
Author(s):  
Andrea Valle
Keyword(s):  
Computer Music ◽  
The Other ◽  
Sound Sources ◽  
Sound Installation ◽  
Dc Motors ◽  
Design Production ◽  
Computer Based ◽  
Anthropological Approach ◽  
Generating System ◽  
Sound Generator

The article describes the design, production and usage of the ‘Rumentarium’, a computer-based sound generating system involving physical objects as sound sources. The Rumentarium is a set of handmade resonators, acoustically excited by DC motors, interfaced to the computer by means of various microcontrollers. Following an ecological/anthropological approach, in the Rumentarium discarded materials are used as sound sources. Every instrument is ‘produced while designed’ in an improvisation-like manner, starting from available materials. In this way, hardware is ‘softened’: that is, it can be continuously modified as in software development. Analogously, the onsite setup is very light, so that components can be added or removed on the fly, even while the Rumentarium is at work. Differently from typical computer music, the Rumentarium, while entirely computationally controlled, is an acoustic sound generator. On one hand, the Rumentarium can be played like an instrument in conjunction with a MIDI controller, for use in live musical performance. On the other side, it can be driven by algorithmic strategies. In this way, the Rumentarium can be configured also as a sound installation, in a standalone mode. Some artistic works are discussed while introducing the various control modalities that have been specifically developed for the Rumentarium.

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