Absorption de sodium, calcium et potassium lors d'interactions ioniques au cours de la phase de germination de Raphanus sativus

1982 ◽  
Vol 60 (9) ◽  
pp. 1639-1646 ◽  
Author(s):  
Gilles Guerrier
Keyword(s):  
Raphanus Sativus ◽  
External Solution ◽  
Sodium Content ◽  
The Other ◽  
Mineral Analysis ◽  
Sodium Calcium ◽  
Germination Medium ◽  
Other Hand ◽  
Raphanus Sativus L ◽  
High Concentrations

Na+–K+ and Na+–Ca2+ interactions are measured by mineral analysis of germinating plantlets of radish (Raphanus sativus L.) in nutritive solutions enriched in these three elements. With high concentrations of CaCl2, more than 2.5 mM, the absorption of sodium is stimulated especially when there is a high percentage of this element in the external solution. On the other hand, KCl brings about a decrease in the sodium content in the hypocotyl, cotyledons and root; no one organ is affected. Only the uptake of sodium is modified not its transport, which is always proportional to the quantity absorbed. The absorption of calcium and potassium does not evolve in proportion to their external amounts, and the inhibition of accumulation of these elements by sodium is not dependent on the concentration of NaCl. The uptake of calcium is more inhibited than that of potassium which varies with the quantities of KCl and NaCl in the germination medium. Thus, potassium inhibits the uptake of sodium more than sodium inhibits that of potassium. However, whereas the absorption of sodium is only slightly modified by calcium, the absorption of calcium depends highly on the concentration of sodium.

Nutritional Requirement for 4-Aminobenzoate Caused by Mutation of Dihydropteroate Synthetase

1976 ◽  
Vol 31 (5-6) ◽  
pp. 285-287 ◽  
Author(s):  
Helmut Rappold ◽  
Adelbert Bacher
Keyword(s):  
Parent Strain ◽  
The Other ◽  
Synthetase Activity ◽  
Nutritional Requirement ◽  
Wild Type ◽  
Aerobacter Aerogenes ◽  
Low Level ◽  
Other Hand ◽  
High Concentrations

Abstract Aerobacter aerogenes mutant 62-1 AC requires high concentrations of 4-aminobenzoate for growth. The mutant accumulates N-glucosyl-4-aminobenzoate and has an intact 4-aminobenzoate synthetase (Bacher, Gilch, Rappold, and Lingens, Z. Naturforsch. 28c, 614 - 617 [1973]). On the other hand the ability of the mutant to synthesize dihydropteroate is markedly reduced. The dihydropteroate synthetase level of mutant 62-1 AC is 1% as compared to the parent strain. Spontaneous revertants of mutant 62-1 AC show wild type levels of dihydropteroate synthetase. We conclude that the requirement for 4-aminobenzoate in mutant 62-1 AC is due to poor utilization of 4-aminobenzoate as a consequence of the low level of dihydropteroate synthetase activity.

Source of N-nitrosodimethylamine in river waters of the upper Tone River basin in Japan

2010 ◽  
Vol 62 (11) ◽  
pp. 2550-2557 ◽  
Author(s):  
K. Kosaka ◽  
K. Fukui ◽  
M. Asami ◽  
M. Akiba
Keyword(s):  
River Basin ◽  
The Other ◽  
Processing Plant ◽  
Sewage Effluent ◽  
River Waters ◽  
Industrial Discharge ◽  
Other Hand ◽  
High Concentrations ◽  
Kanto Region

The presence of N-nitrosodimethylamine (NDMA) in the Hirose River and its tributaries, located in the upper Tone River basin, in the Kanto region of Japan, was investigated. NDMA was detected at high levels in the Arato River, one of the tributaries of the Hirose River, at high concentrations (up to 2,100 ng/L). Due to the confluence of the Arato River, NDMA concentration in the Hirose River increased (up to 61 ng/L). The NDMA in the Arato River was due to industrial discharge from a livestock processing plant located near the river. There were three discharges at the plant, with NDMA concentrations of 78, 11, and 33,000 ng/L. The industrial discharges from the livestock processing plant did not contain significant amounts of NDMA precursors on chloramination. On the other hand, sewage effluent was shown to contain NDMA precursors. The amounts of NDMA precursors in the sewage effluent that were rapidly transformed into NDMA were considered to be lower than those slowly transformed into NDMA.

Specific Inhibition of Platelet Agglutination and Aggregation by Aromatic Amidino Compounds

1978 ◽  
Vol 39 (02) ◽  
pp. 411-425 ◽  
Author(s):  
J D Geratz ◽  
R R Tidwell ◽  
K M Brinkhous ◽  
S F Mohammad ◽  
O Dann ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Human Plasma ◽  
Inhibitory Effect ◽  
The Other ◽  
Specific Inhibition ◽  
Test Systems ◽  
Other Hand ◽  
Bovine Plasma ◽  
Inhibitory Activities ◽  
High Concentrations

SummaryA series of aromatic amidino compounds were investigated for their inhibitory effect on platelet agglutination and platelet aggregation. Agglutination of fresh or fixed platelets was produced by bovine plasma or by human plasma in combination with ristocetin, while aggregation of fresh platelets was induced by ADP, thrombin or collagen. Highly effective inhibitors were found for both types of platelet clumping, but there was no parallelism between the inhibitory activities in the two test systems. 5-(5-amidino-2-benzimidazolyl)-2-(4-hydroxyben-zene)benzimidazole suppressed agglutination exclusively. Pentamidine, on the other hand, strongly blocked the aggregation reactions, but did not interfere with agglutination, even at high concentrations. Compounds which inhibited aggregation also prevented the liberation of serotonin from the platelets.

Exploring the migration of Muslims, Hindus and Sikhs in Birmingham by ward concentration and deprivation

2021 ◽  
Vol 18 (3) ◽  
pp. 339-348
Author(s):  
Serena Hussain
Keyword(s):  
The Other ◽  
Economic Disadvantage ◽  
Other Hand ◽  
High Concentrations ◽  
The Relationship ◽  
Group Concentration

This paper explores the migration within as well as migration to Birmingham of Muslims, Hindus and Sikhs. It provides analysis and reflection on the relationship between migration, faith group concentration and deprivation. The findings demonstrate how Muslim, Hindu and Sikh migration trends differ for specific wards characterised by contrasting levels of both socio-economic disadvantage and faith group clustering. Hindus are shown to migrate to more affluent areas, however this does not necessarily translate to moving away from wards where there are clusters of the same faith group, as discussion on Hall Green illustrates. Muslims, on the other hand, displayed a greater propensity to move away from wards with high concentrations of the same faith group, yet this did not also result in moving to more affluent wards.

Adaptation of the PolychaeteNereis Diversicolorto Estuarine Sediments Containing High Concentrations of Zinc and Cadmium

1973 ◽  
Vol 53 (4) ◽  
pp. 839-857 ◽  
Author(s):  
G. W. Bryan ◽  
L. G. Hummerstone
Keyword(s):  
The Other ◽  
Estuarine Sediments ◽  
Nereis Diversicolor ◽  
Other Hand ◽  
High Concentrations

In the first paper of this series (Bryan & Hummerstone, 1971) it was shown that in the estuarine polychaeteNereis diversicolorO. F. Müller the concentration of copper is roughly proportional to that of the surrounding sediment. On the other hand, concentrations of zinc appeared to be relatively independent of those in the sediment and it was suggested that the level of zinc in the worm is regulated.

Distribution of recently absorbed zinc in subterranean clover (Trifolium subterraneum L.) determined by adding radioactive zinc to the culture soultion

1960 ◽  
Vol 11 (6) ◽  
pp. 887 ◽  
Author(s):  
DS Riceman ◽  
GB Jones
Keyword(s):  
Zinc Deficiency ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Main Axis ◽  
Leaf Primordia ◽  
The Other ◽  
Subsequent Growth ◽  
Other Hand ◽  
Radioactive Zinc ◽  
High Concentrations

The distribution of zinc recently absorbed as 65Zn into subterranean clover (T. subterraneum L. var. Bacchus Marsh) from culture solutions has been examined by means of radioautographs in normal plants and in plants recovering from a state of zinc deficiency. In normal plants which had been grown initially in cultures containing non-radioactive zinc, the recently absorbed zinc reached high concentrations in the roots, main axis, and youngest leaves but very little of it moved into the older, fully expanded leaves. In plants recovering from the deficiency, on the other hand, the recently absorbed zinc reached high concentrations in all the living organs, including the oldest leaves. Growth of the "little" leaves or other leaves affected by the deficiency was not resumed after the entry of zinc into their tissues. Recovery of the plant depended upon the production of new leaves by the leaf primordia and upon their subsequent growth and emergence.

EFFECT OF AN OVULATORY DOSE OF LUTEINIZING HORMONE ON THE CONCENTRATION OF OESTRONE, OESTRADIOL AND PROGESTERONE IN THE RABBIT OVARIAN FOLLICLES

1976 ◽  
Vol 82 (4) ◽  
pp. 792-800 ◽  
Author(s):  
Vasant V. Patwardhan ◽  
André Lanthier
Keyword(s):  
Luteinizing Hormone ◽  
Follicular Fluid ◽  
Ovarian Follicles ◽  
Mature Female ◽  
The Other ◽  
Other Hand ◽  
High Concentrations ◽  
Sexually Mature

ABSTRACT This study was done to determine the effect of an ovulatory dose of LH on the concentration of oestrone, oestradiol and progesterone in the follicular tissue and in follicular fluid of ovaries of sexually mature female rabbits. Eight animals were sacrificed without treatment while others (4 to a group) were sacrificed at 1, 3, 4, 6, 8 and 10 h after administration of LH (50 μg). In each animal follicles from both ovaries were pooled and the follicular tissue was separated from the fluid. Determination of oestrone, oestradiol and progesterone was done by radioimmunoassay separately in the follicular tissue and in fluid. One hour after LH treatment oestrogen levels were found elevated, as compared to the control, in the fluid but not in the tissue. Thereafter oestrogen levels declined and reached levels much below control at times nearing ovulation. On the other hand, progesterone levels were elevated over the control in both the tissue and fluid at 1 and 3 h. The tissue progesterone levels were, however, below control at and after 6 h. The sustained high concentrations of tissue progesterone in the earlier period after LH stimulation could play a role in the chain of events leading to follicular rupture.

EFFECT OF STEROIDS AND COFACTORS ON THE ACTIVITY AND STABILITY OF HUMAN PLACENTAL GLUTAMATE DEHYDROGENASE

1966 ◽  
Vol 51 (4) ◽  
pp. 599-608
Author(s):  
Dale M. Peterson ◽  
James C. Warren
Keyword(s):  
Glutamate Dehydrogenase ◽  
Sex Hormones ◽  
Human Placenta ◽  
Initial Velocity ◽  
Significant Inhibition ◽  
The Other ◽  
Other Hand ◽  
High Concentrations ◽  
The Stability ◽  
Uncompetitive Inhibitor

ABSTRACT Glutamate dehydrogenase (EC 1. 4. 1. 3.) has been purified approximately 3700 fold from human placenta. The effects of sex hormones and co-factors on the activity and stability of this preparation have been studied. NAD+ was noted to activate this enzyme at high concentrations while NADP+ did not. Mg2+ was shown to be a competitive activator of glutamate with NADP+ as cofactor and an uncompetitive inhibitor of glutamate with NAD+ as cofactor. With NAD+ as cofactor, steroids at concentrations physiological for placenta had no effect on activity while significant inhibition of initial velocity by 1.0 μm oestrone and 17β-oestradiol and 2.0 μm progesterone was seen with NADP+ as co-factor. The stability of the enzyme was uneffected by several steroids alone at 20 μm concentrations. The stability of the enzyme was markedly decreased by NADPH but natural steroids at physiological concentrations failed to potentiate this cofactor induced instability. Mg2+ ion, ATP and ADP at physiological concentrations, on the other hand, clearly protect the enzyme against NADPH. These observations militate against steroid effects on stability but do not exclude steroid inhibition of activity with NADP+ as cofactor as a possible mechanism of steroid action, at least in placenta.

Inactivation of Factor VIII by a Mechanism Independent of the Generation of Thrombin

1979 ◽  
Vol 42 (03) ◽  
pp. 838-847 ◽  
Author(s):  
D C Triantaphyllopoulos
Keyword(s):  
Factor Viii ◽  
Factor Xa ◽  
Factor Ix ◽  
The Other ◽  
Factor X ◽  
Complete Inactivation ◽  
Thrombin Activity ◽  
Other Hand ◽  
High Concentrations

SummaryThrombin first activates and then inactivates factor VIII and for this reason thrombin has been considered responsible for the inactivation of factor VIII which occurs during clotting. Experiments described in this paper indicated that the activity of factor VIII is not reduced in factor IX or factor X deficient sera, while on the other hand this factor becomes inactivated in blood anticoagulated with high concentrations of hirudin which inhibit thrombin activity completely. This suggests that some other factor, besides thrombin, which is generated only in trace amounts in factor IX or factor X deficient plasmas, is also able to inactivate factor VIII. Purified factor X activated with insolubilized trypsin was added to purified preparations of factor VIII, which were free of both fibrinogen and prothrombin. Factor Xa was allowed to act for 5-60 minutes and then inactivated with phenylmethanesul- fonyl fluoride. Depending on the duration of the action of factor X a partial or complete inactivation of factor VIII was observed. This inactivation was also observed in the presence of hirudin, thus excluding the possibility that the effect was due to contamination with trace amounts of thrombin.

scholarly journals Honey bee (Apis mellifera) distribution and behaviour on hybrid radish (Raphanus sativus L) crops

2011 ◽  
Vol 64 ◽  
pp. 32-36 ◽  
Author(s):  
L.J. Evans ◽  
R.M. Goodwin ◽  
M.K. Walker ◽  
B.G. Howlett
Keyword(s):  
Apis Mellifera ◽  
Seed Production ◽  
Honey Bees ◽  
Raphanus Sativus ◽  
The Other ◽  
Single Plant ◽  
Production Lines ◽  
Pollen Donor ◽  
Vegetable Seed ◽  
Raphanus Sativus L

Commercial hybrid vegetable seed production involves movement of pollen between two distinct groups of plants (parent lines) a pollen donor and seed production lines The aim of this study was to observe the distribution and behaviour of honey bees (Apis mellifera) on hybrid radish (Raphanus sativus L) crops in New Zealand Honey bees were observed to have an even distribution across the parent lines although individual bees largely maintained fidelity to the particular line on which they foraged Of the bees observed on malefertile flowers 72 did not switch to the other line When plants from the different lines were manipulated so that they appeared to be a single plant 695 of honey bees remained constant to the line visited To maximise the effectiveness of honey bees as pollinators of hybrid radish techniques should focus on better matching of lines or breeding of lines to reduce pollinator differentiation

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