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PubMed1992

[RNA synthesis and transport in the rat liver under the effects of pesticide cotoran (fluometuron)].

The experiments on the investigation of pesticide cotoran-effect on RNA synthesis and transport were carried out. Cotoran was shown to destroy considerably the processes of RNA biosynthesis in rat liver, that results in the decrease of RNA transport from nuclei into cytoplasm. By special experiments it was established that functional activity and the integrity of nuclear membrane (according to the alteration in the activity of nuclear membrane enzyme Mg2-dependent ATP-ase) was not destroyed.

Animals↗
PubMed1992

[Effects of pesticide fluometuron (cotoran) on template synthesis of RNA].

The experiments on the investigation of pesticide fluometuron (cotoran) influence on nuclease sensitivity and template activity of rat liver chromatin were carried out. Cotoran was found to bind specifically with non-histone proteins of chromatin. It was shown that this pesticide considerably decreases template activity of chromatin and its sensitivity to the action of nucleases. It suggests, that certain conformation changes occur in chromatin upon the action of cotoran.

Animals↗
PubMed2003

Metallothionein induction in the aquatic oligochaete Tubifex tubifex exposed to the herbicide isoproturon.

Metallothioneins (MTs), are low molecular weight proteins, mainly involved in metal ion detoxification. Recently it has been demonstrated that MTs participate in several cellular functions such as regulation of growth, and anti-oxidative defenses. Moreover, pesticides can induce their synthesis. The aim of the current work was to determine the effects of isoproturon either pure or formulated as Matin (suspension containing 500 g x l(-1) isoproturon) on the metallothionein and total protein content of the aquatic worm Tubifex tubifex. MT levels in exposed worms increased significantly after 7 and 15 days of exposure to 50 mg x l(-1) of herbicide. Isoproturon reduced metal (Cu, Zn, and Cd) content of metallothioneins, and it also increased total protein content of the worms. The results suggest that MT induction may not be considered as a specific biomarker of metal exposure but it can be used as a non specific biomarker of isoproturon effect in the worm.

Animals↗
PubMed2004

Effect of different chemical and mechanical defolation methods on the skin quality of potatoes.

Without foliage destruction an efficient harvest is impossible. Potatoes for the fresh market are often harvested when the foliage is still heavy green due to tuber size and starch content that must be limited. Tubers from immature vines are typically very susceptible to skinning and mechanical injury during harvest. Young tubers from immature vines need more time after foliage destruction to set periderm than tubers from senescent vines where the formation of periderm is already started. Spray schemes based on metoxuron, carfentrazone-ethyl and diquat at a dose of 300 g/ha caused slower leaf and stem desiccation. Over the 3 growing seasons it could be concluded that mechanical foliage destruction in combination with carfentrazone-ethyl + mineral oil promoted periderm formation better than the other desiccation schemes tested. A split treatment with diquat at 300 g/ha or carfentrazone-ehtyl + mineral oil followed by a second application of diquat or carfentrazone-ethyl can led to a slower periderm formation and even give secondary growth. A double treatment of diquat (300 g/ha) or carfentrazone-ethyl + mineral oil followed by diquat (600 g/ha) after 3 days gave satisfactory results. Rhizoctonia tuber infection increased with a longer field period after treatment. In general the increase was more pronounced for the spray schemes where skin set of the tubers was less fast.

Belgium↗
PubMedDate not supplied

Binding of Salmonella strains to immobilized intestinal mucosal preparations from broiler chickens.

The binding kinetics of radiolabeled Salmonella california 1989/O (mannose-sensitive hemagglutinin-positive [MSHA+]) to immobilized mucus or enterocytes isolated from broiler ceca and inhibition of binding by D-mannose and sodium metaperiodate were characteristic of adherence of mannose-sensitive type 1 fimbriae of bacteria to eukaryotic mannose-containing receptors. Binding by radiolabeled strains 1989/O (in the presence of D-mannose) and S. typhimurium S 7471 N (MSHA-, non-fimbriated) indicated non-specific binding that was characterized by less binding to enterocytes and mucus and lack of inhibition by carbohydrates or prior treatment with sodium metaperiodate. Inhibition of non-specific binding to enterocytes by pretreatment with various enzymes or by the presence of tetramethylurea or p-nitrophenol (known to disrupt hydrophobic interactions) indicate involvement of multiple sites and hydrophobic bonding. Strain-specific outer-membrane preparations inhibited non-specific binding to a greater extent than did lipopolysaccharide, Escherichia coli outer-membrane preparations, or bovine serum albumin.

Animals↗
PubMedDate not supplied

[Reduction paths of reaction centers of photosystem I of photosynthesis].

The behaviour of ESR signal I in blue-green algae and chloroplasts is considered under various illumination and with various previous treatment. It is shown that the main process determining the kinetics of P700 plus reduction is the reaction with reduced components of the electron transfer chain between the two photosystems. If the accumulation of the products is inhibited by any way, then the reduction rate depends on the reactions with reducing agents in the incubation medium accumulated under irradiation before experiment. These exogenic reducing agents may be removed from the chloroplasts with repeated washings, and from algae-by means of the dark incubation for a long time. The relation of cyclic and noncyclic electron transfer is considered with and without artificial cyclic flow mediator.

Chloroplasts↗
PubMedDate not supplied

[Kinetics of dark reduction of P700 centers in photosynthesis].

Relationship between the rate of dark fall of ESR I signal in the chloroplasts and light intensity 710 nm was studied. It is shown that the kinetics of the signal drop at sufficiently high levels of intensity is a biphase one. The fast phase (2 sec) disappears in the presence of an inhibitor of noncyclic electron transfer. It is concluded that the kinetics of electron transport is not described within the concept of the linear chain of electron carriers and a suggestion is put forward concerning a possible mechanism of this process which depends on the participation of plastoquinone in electron transport.

Chloroplasts↗
PubMed1991

[The translocation and specific binding of the pesticide fluometuron (cotoran) with the proteins of rat liver nuclei].

Intracellular distribution of labeled cotoran was studied. 3H-cotoran was shown to penetrate through the nuclear membrane to accumulate uneventfully in the intranuclear components. An insignificant amount of 3H-cotoran was associated with the nucleoplasm and the outer nuclear membrane. At the same time, essential radioactivity was observed in the proteins of the nuclear matrix (up to 30%) and in non-histone proteins of chromatin (up to 60%). Acception of 3H-cotoran on metaphase chromosomes of cultured cells as well as specificity of cotoran binding with non-histone proteins of chromatin in vivo and in vitro was studied by radioautography. It was revealed that cotoran was translocated into the interphase nuclei to be accepted by metaphase chromosomes of the HeLa line cells and fibroblasts in human embryo, and specifically, in receptor-like manner, bound to chromatin proteins.

Animals↗
PubMed1991

Monuron.

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Air Pollutants, Occupational↗
PubMed1990

Dermal toxicity to rats of isoproturon technical and formulation.

Information on the toxicity of urea-based herbicides is meagre and no data are available on the subacute dermal toxicity of isoproturon and its formulation. Repeated applications of isoproturon technical (IPT) and its wettable powder formulation (IPF) to the skin of male and female rats for 21 days caused mild to moderate toxic effects. IPT was more toxic to male rats as evidenced by animal mortality and enzymatic and hematological changes. The toxicity of IPF was less to both sexes. No dose response relationship could be established since the enzymatic and hematological changes produced by 3 different dose levels were equal.

Alanine Transaminase↗