Membrane destruction

Imibenconazole is a triazole fungicide exhibiting direct cell membrane destruction as well as sterol biosynthesis inhibition for controlling major diseases of fruits, vegetables, cereals, ornamentals and turf. 

Lymphocyte Membrane Protection by Antioxidants against N02 Cell Membrane Destruction Is Shown by Cell Staining with Eosin... 

Other systems like electroporation have no lipids that might help in membrane sealing or fusion for direct transfer of the nucleic acid across membranes they have to generate transient pores, a process where efficiency is usually directly correlated with membrane destruction and cytotoxicity. Alternatively, like for the majority of polymer-based polyplexes, cellular uptake proceeds by clathrin- or caveolin-dependent and related endocytic pathways [152-156]. The polyplexes end up inside endosomes, and the membrane disruption happens in intracellular vesicles. It is noteworthy that several observed uptake processes may not be functional in delivery of bioactive material. Subsequent intracellular obstacles may render a specific pathway into a dead end [151, 154, 156]. With time, endosomal vesicles become slightly acidic (pH 5-6) and finally fuse with and mature into lysosomes. Therefore, polyplexes have to escape into the cytosol to avoid the nucleic acid-degrading lysosomal environment, and to deliver the therapeutic nucleic acid to the active site. Either the carrier polymer or a conjugated endosomolytic domain has to mediate this process [157], which involves local lipid membrane perturbation. Such a lipid membrane interaction could be a toxic event if occurring at the cell surface or mitochondrial membrane. Thus, polymers that show an endosome-specific membrane activity are favorable. 

Blood compatibility. It is important that cellular components of the blood are not disrupted and that serum- or plasma-based responses are not triggered by parenteral administration. Therefore, two mechanisms must be assessed regarding the blood compatibility of component materials. These include the material s effect on cellular components that cause membrane destruction and hemolysis and the activation of the clotting mechanism resulting in the formation of the thromboeboli. 

Polymeric vesicles could be of better use for such an antitumor therapy on a cellular level, since they have at least one of the properties required, namely an extraordinary membrane stability. For a successful application, however, the simple systems prepared so far must be varied to a great extent, because the stability of a model cell membrane is not the only condition to be fulfilled. Besides stability and possibilities for cell recognition as discussed above the presence of cell membrane destructing substances such as lysophospholipids is necessary. These could e.g. be incorporated into the membrane of stabilized liposomes without destruction of the polymeric vesicles. There have already been reports about thekilling of tumor cells by synthetic alkyl lysophospholipids (72). 

In conclusion, in the case of resistant E. coli cultures, the increase in antibacterial activity of the more lipophilic benzylpyrimidines is due not to a favorable influence on the transport through the cell membrane but to their interaction with membrane components leading to membrane destruction and cell death. 

Table IV attempts to summarize information relevant to electrical fields and their effects on biological membranes. Membrane destruction can be achieved with low frequency alternating fields of the order of some hundred millivolts across the membrane, as later described. The propagation of action potentials along nerves is initiated or interfered with by pulses or low frequency potentials of roughly 10 mV across the membrane. Cor-...

Membrane Destruction Action Potential (Excitation) Subtle Effects... 

Studies on the influence of boron have shown that its compounds as borate have inhibited some fermentative reactions. In addition, the influence of boron results in membrane destruction. ... 

Surface discoloration Pit membrane destruction Decomposition of structural polymers Mechanobiochemical Biochemical (decays)... 

Cell membrane destruction may also be caused by toxic enzymes. For example, many organisms secrete enzymes, called phospholipases, which cause the hydrolysis of membrane lipid molecules. Phospholipase A2 is found in the venom of several snakes. 

Under certain conditions, referred to collectively as oxidative stress, antioxidant mechanisms are overwhelmed and some damage may occur. Damage results primarily from enzyme inactivation, polysaccharide depolymerization, DNA breakage, and membrane destruction. Examples of circumstances that may cause serious oxidative damage include certain metabolic abnormalities, the overconsumption of certain drugs or exposure to intense radiation, or repeated contact with certain environmental contaminants (e.g., tobacco smoke). 

It should be noted that early herbicidal symptoms exhibited by higher plants may be different from aquatic microalgae. Membrane destruction caused by many diphenylethers in higher plants apparently leads... 

Electron micrograph illustrating PbS04 membrane destruction [52]. 

Local membrane destruction can be made by suddenly applying a short strong burst of suction. A hole is created in the cell membrane so that the pipette is in direct electrolytic contact with the cell interior. Electrical potentials and currents from the entire cell are measured and are therefore called the whole-cell recording technique. The hole may also be used to inject substances into the interior of the cell. 

More common configurations of PMRs are systems with suspended photocatalyst. In these PMRs various membrane techniques are utilized MF, UF, NF, dialysis, PV, or MD. The photocatalytic reaction in PMRs with suspended photocatalyst might be conducted in (a) a feed tank, (b) a membrane module or (c) an additional reservoir (photoreactor) which is located between the feed tank and the membrane module. Thus, the danger of polymer membrane destruction by UV light could be avoided by a proper selection of reactor configuration. 

The question was arlsed, how can resistant cells eliminate the Inhibition and membrane destruction effect of saponin and polyenes For this fatty acids had to be investigated (Table 4 and 6). 

One of the characteristic reactions of lipids which are exposed to oxygen is the formation of peroxides. Indeed, among non-enzymic chemical reactions which take place in the environment at ambient temperatures, the oxidation of unsaturated compounds is perhaps the most important both from an industrial and a medical point of view. In biological tissues, uncontrolled lipid peroxidation causes membrane destruction and is increasingly regarded as an important event in the control or development of diseases (section 8.11). In food, oxidation (either enzymically or chemically catalysed) can have desirable as well as adverse consequences (section 8.15). 

Our results coincide with those of other authors who studied the produced hyperkalemia due to jellyfish and fish poison injection (Larsen and Price, 1978 and Mansour et al, 1980) who attributed this result to cell membrane destruction. 

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