That destroy membrane integrity

Liposome Delivery Systems Membrane Transport A Clinical Perspective Antibiotics That Destroy Membrane Integrity... 

Lysophosphatidylcholine is a frequent product of oxidized phospholipid hydrolysis and shows structural similarities to its diacyl counterparts containing a short acyl chain in sn-2 position. Therefore, its cellular activities deserve particular attention, especially in the context of its cytotoxicity. The effects of phospholipid oxidation products and lyso-PC depend not only on their concentration but also on the cell type. Lyso-PC containing a long acyl chain in sn- position (e.g. C16 0, C18 0) is an amphiphilic phospholipid that is generated by phospholipase-catalyzed hydrolysis of phosphatidylcholine or extensive oxidation leading to loss of the entire sn-2 acyl chain. Its critical micellar concentration (CMC) is around 50 pM. It is easily taken up into lipid membranes and increases their fluidities . Above the CMC it forms micelles that destroy membrane integrity also by removal of proteins as shown in erythrocytes (Bierbaum et al., 1979 Colics and Chisholm, 2000). Lyso-PC exerts apoptotic effects in rVSMCs at concentrations below its CMC and induces necrotic cell death at concentrations above its CMC (Hsieh et al.,... 

Mechanism of Action An antifungal agent that inhibits ergosterol synthesis. Therapeutic Effect Destroys cytoplasmic membrane integrity of fungi. Fungicidal. Pharmacokinetics Low systemic absorption. Absorbed and distributed in each layer... 

In adapting water-insoluble catalysts for use in biological systems it is necessary to introduce the catalyst into the membrane using a solvent vector. Solvents such as tetrahydrofuran and dimethyl sulfoxide have been found to be useful. The introduction of catalyst in a minimum amount of solvent, which is miscible with water, causes the insoluble complex to partition into the hydrophobic domain created by the lipid substrate. The catalyst obviously cannot be removed subsequently from the substrate without destroying the integrity of the membrane. It is also important to verify that the solvent used to introduce the catalyst does not perturb the stability of the membrane. 

Finally, chlorine will oxidize the membrane polymer and, in effect, destroy the integrity of the membranes. Specifically, the chlorine attacks the amide functional group that destroys the hydrogen-bond linkages in the polymer. " ... 

Valli et al. (88) suggested that intracellular nitroreductases may be involved in 2,4-DNT reduction by R chrysosporium. Even though intracellular nitroreductases of R chrysosporium probably exist, there is no current evidence that supports their involvement in TNT reduction. Conversely, there are a number of experiments which suggest that TNT is reduced by a plasma membrane redox system in R chrysosporium (81). TNT reduction requires live, intact mycelia. Any condition that disrupts the integrity of the plasma membranes (freeze-thawing or grinding) destroys the reduction activity. Also, no significant reduction is observed with either supplemented (NADPH, NADH, or ATP) or unsupplemented extracellular or intracellular fractions of the culture, under aerobic or anaerobic conditions (81). 

Table 3 shows pA values for practolol and propranolol against isoprenaline induced tachycardia in the guinea pig atria, relaxation of the tracheal chain, and adenylate cyclase activity of purified membrane fragments prepared from guinea pig heart and lung. While practolol is clearly cardioselective in the tissue preparations it becomes non-selective on the membrane fragments. It is conceivable that in the purification of the membranes the integrity of the micro-environment which controls access to the receptors in the different tissues, is destroyed. 

Alkalies cause toxicity by liquefaction necrosis, meaning that the alkali destroys the cell membrane and cell integrity and thereby causes cell lysis. 

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