Inhibitory effects of elevated endogenous cytokinins on nitrate reductase in ipt -expressing tobacco are eliminated by short-term exposure to benzyladenine

2002 ◽  
Vol 115 (2) ◽  
pp. 284-290 ◽  
Author(s):  
Matej Lexa ◽  
Todor Genkov ◽  
Břetislav Brzobohatý
Keyword(s):  
Nitrate Reductase ◽  
Inhibitory Effects ◽  
Short Term ◽  
Short Term Exposure ◽  
Endogenous Cytokinins

Short-term effects of nitrate on nitrate reductase activity and symbiotic dinitrogen fixation in faba bean and pea

1988 ◽  
Vol 66 (8) ◽  
pp. 1639-1645 ◽  
Author(s):  
Francois-P. Chalifour ◽  
Louise M. Nelson
Keyword(s):  
Nitrate Reductase ◽  
Faba Bean ◽  
Nitrite Reductase ◽  
Nitrate Reductase Activity ◽  
Reductase Activity ◽  
Inhibitory Effects ◽  
Short Term ◽  
Pisum Sativum L ◽  
Vicia Faba L ◽  
Legume Symbiosis

The effects of a short-term supply of combined nitrogen (N) on the Rhizobium–legume symbiosis were studied in faba bean (Vicia faba L.) and pea (Pisum sativum L.) nodulated by R. leguminosarum biovar viceae isolate 175F5 or 175F19 and subjected to increasing levels of [Formula: see text] (0, 5, 10, or 20 mol∙m−3) from 28 to 36 days after planting. Trends in N2-fixing activity (acetylene reduction) showed that faba bean was more tolerant to [Formula: see text] than pea with isolate 175F5 but not with isolate 175F19. Nitrite reductase activities in the leaf, root, and nodule cytosol fractions were severalfold higher than nitrate reductase activities for both hosts. The levels of these enzymes in the nodule cytosol, the absence of bacteroid nitrate reductase and the lack of induction of bacteroid nitrite reductase in response to [Formula: see text] addition are consistent with the lack of [Formula: see text] accumulation in nodules of both hosts. Therefore, it is unlikely that the inhibitory effects of [Formula: see text] on N2 fixation are due to [Formula: see text] inhibition of nitrogenase. The relative levels of nitrate reductase activity in the root and nodule cytosol fractions were, respectively, higher and lower in the two faba bean symbioses ([Formula: see text] tolerant) and in the pea–175F5 symbiosis ([Formula: see text] sensitive) than in the pea–175F19 symbiosis ([Formula: see text] tolerant).

scholarly journals Short-Term and Long-Term Inhibitory Effects of Copper on Anammox Process

Proceedings ◽  
2018 ◽  
Vol 2 (11) ◽  
pp. 657 ◽  
Author(s):  
Cigdem Kalkan Aktan ◽  
Ayse Ekin Uzunhasanoglu ◽  
Kozet Yapsakli ◽  
Bulent Mertoglu
Keyword(s):  
Competitive Inhibition ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Anammox Bacteria ◽  
Inhibitory Effects ◽  
Short Term ◽  
Inhibition Model ◽  
Short Term Exposure ◽  
Anammox Process

The main goal of this study is to evaluate the short-term and long-term inhibitory effects of Cu (II) on Anammox process. To investigate the short-term inhibition level, four different concentrations (1, 2.5, 5 and 10 mg L−1 as Cu2+) were tested in batch reactors. IC50 levels for short-term exposure deduced as 4.57mg L−1 (R2: 0.97) from the modified non-competitive inhibition model. Lab-scale continuous flow up-flow fixed bed reactor with Kaldness biofilm carriers was operated 240 days with gradually increased Cu concentrations (from 0.2 to 8 mg L−1). To identify the IC50 levels in case of prolonged exposure of Cu(II), experimental data were fitted with a modified non-competitive inhibition model, and calculated as 6.77 mg L−1 (R2: 0.95). The results show that the IC50 level for copper in long-term exposure was higher than in short-term exposure and the possible reason for that is the self-adaptation of Anammox bacteria.

scholarly journals Hemin attenuates response of primary rat adipocytes to adrenergic stimulation

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12092
Author(s):  
Tomasz Szkudelski ◽  
Karina Frąckowiak ◽  
Katarzyna Szkudelska
Keyword(s):  
Inhibitory Effect ◽  
Heme Oxygenase 1 ◽  
Adrenergic Stimulation ◽  
Inhibitory Effects ◽  
Short Term ◽  
Isolated Cells ◽  
Lactate Release ◽  
Rat Adipocytes ◽  
Beneficial Effects ◽  
Short Term Exposure

Hemin is an activator of heme oxygenase-1 (HO-1), an enzyme catalyzing heme degradation. Up-regulation of HO-1 is observed in response to various pathological conditions. Moreover, pharmacological activation of HO-1 is associated with numerous beneficial effects in the organism. Hemin was shown to exert, among other, anti-diabetic and anti-obesity properties. These effects are strongly linked with adipose tissue. However, the direct influence of hemin on metabolism of the fat cells have not been explored. The present study aimed to determine the short-term effects of hemin on metabolism of the primary rat adipocytes. We focused on processes directly related to lipid accumulation, such as lipogenesis and lipolysis. For this purpose, the isolated cells were subjected for 2 h to 40 µM hemin, and effects of this compound on insulin-stimulated glucose conversion to lipids, lactate release, lipolysis induced by various stimuli, and also on the antilipolytic action of insulin were determined. It was shown that hemin did not affect insulin-induced lipogenesis and lactate release. However, hemin significantly decreased lipolysis stimulated by epinephrine. The inhibitory effect of hemin on epinephrine-induced lipolysis was not abolished in the presence of SnMP, an inhibitor of HO-1, which suggests hemin action irrespective of this enzyme. Similar inhibitory effects on epinephrine-induced lipolysis were observed in the presence of 3 and 12 mM glucose. Moreover, hemin was shown to reduce epinephrine-induced lipolysis also when glucose was replaced by alanine or by succinate. Apart from changes in epinephrine action, it was found that the lipolytic response of the adipocytes to isoproterenol was also diminished by hemin. However, hemin failed to affect lipolysis stimulated by dibutyryl-cAMP (a direct activator of protein kinase A), forskolin (an activator of adenylate cyclase), and also by DPCPX (an adenosine A1 receptor antagonist). Additionally, epinephrine-induced lipolysis was shown to be decreased by insulin, and this effect was deepened in the presence of hemin. These results indicate that short-term exposure of the adipocytes to hemin does not affect processes related to glucose metabolism, such as lipogenesis and lactate release. However, hemin was found to decrease the lipolytic response to adrenergic stimulation, which is associated with reduced lipid release from adipocytes. Moreover, our results indicate that hemin is also capable of diminishing the exaggerated lipolysis, which occurs in the presence of supraphysiological concentrations of glucose.

A short-term exposure of cucumber plants to rising atmospheric CO 2 increases leaf carbohydrate content and enhances nitrate reductase expression and activity

Planta ◽  
2001 ◽  
Vol 212 (2) ◽  
pp. 305-312 ◽  
Author(s):  
Bibiana Larios ◽  
Eloisa Agüera ◽  
Purificación de la Haba ◽  
Rafael Pérez-Vicente ◽  
José M. Maldonado
Keyword(s):  
Nitrate Reductase ◽  
Carbohydrate Content ◽  
Short Term ◽  
Short Term Exposure ◽  
Expression And Activity

The Effect of Dimethyl Sulfoxide on In Vitro Platelet Function

1976 ◽  
Vol 36 (01) ◽  
pp. 221-229 ◽  
Author(s):  
Charles A. Schiffer ◽  
Caroline L. Whitaker ◽  
Morton Schmukler ◽  
Joseph Aisner ◽  
Steven L. Hilbert
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Dimethyl Sulfoxide ◽  
Platelet Function ◽  
Platelet Volume ◽  
Short Term ◽  
Platelet Factor ◽  
Short Term Exposure ◽  
Structural Abnormalities

SummaryAlthough dimethyl sulfoxide (DMSO) has been used extensively as a cryopreservative for platelets there are few studies dealing with the effect of DMSO on platelet function. Using techniques similar to those employed in platelet cryopreservation platelets were incubated with final concentrations of 2-10% DMSO at 25° C. After exposure to 5 and 10% DMSO platelets remained discoid and electron micrographs revealed no structural abnormalities. There was no significant change in platelet count. In terms of injury to platelet membranes, there was no increased availability of platelet factor-3 or leakage of nucleotides, 5 hydroxytryptamine (5HT) or glycosidases with final DMSO concentrations of 2.5, 5 and 10% DMSO. Thrombin stimulated nucleotide and 5HT release was reduced by 10% DMSO. Impairment of thrombin induced glycosidase release was noted at lower DMSO concentrations and was dose related. Similarly, aggregation to ADP was progressively impaired at DMSO concentrations from 1-5% and was dose related. After the platelets exposed to DMSO were washed, however, aggregation and release returned to control values. Platelet aggregation by epinephrine was also inhibited by DMSO and this could not be corrected by washing the platelets. DMSO-plasma solutions are hypertonic but only minimal increases in platelet volume (at 10% DMSO) could be detected. Shrinkage of platelets was seen with hypertonic solutions of sodium chloride or sucrose suggesting that the rapid transmembrane passage of DMSO prevented significant shifts of water. These studies demonstrate that there are minimal irreversible alterations in in vitro platelet function after short-term exposure to DMSO.

Short-term exposure and long-term consequences of neonatal exposure to Δ9-tetrahydrocannabinol (THC) and ibuprofen in mice

2016 ◽  
Vol 307 ◽  
pp. 137-144 ◽  
Author(s):  
Gaëtan Philippot ◽  
Fred Nyberg ◽  
Torsten Gordh ◽  
Anders Fredriksson ◽  
Henrik Viberg
Keyword(s):  
Neonatal Exposure ◽  
Short Term ◽  
Short Term Exposure ◽  
Long Term Consequences

scholarly journals The impact of long- and short-term exposure to different ambient air pollutants on cognitive function in China

2021 ◽  
Vol 151 ◽  
pp. 106416
Author(s):  
Huaxi Gao ◽  
Jieran Shi ◽  
Hongguang Cheng ◽  
Yaqin Zhang ◽  
Yan Zhang
Keyword(s):  
Cognitive Function ◽  
Air Pollutants ◽  
Ambient Air ◽  
Short Term ◽  
Ambient Air Pollutants ◽  
Short Term Exposure ◽  
The Impact
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