Induced leakage

Fan-assisted exhaust ventilation Extract ventilation of a space by means of a fan, with the supply air provided by induced leakage into the building. 

Induced leakage Leakage into an enclosure to equalize a pressure difference due to natural or mechanical ventilation. 

Allen T, Cleland L. Serum-induced leakage of liposome contents. Biochim Biophys Acta 1980 597 418. 

In principle, liposomes can enter (target) cells through different pathways by direct fusion of liposomes and the plasma membrane (1) or by an endo-cytic uptake mechanism. Other liposome-cell interactions that have been described in the literature are absorption, phospholipid and protein exchange, and cell-induced leakage of liposome contents (2,3). 

Holan proposed that the benzylic substituents of DDT analogs would fit into the channel of a pore in the cell membrane to induce leakage of Na+ ion 80). He demonstrated that the optimum dimension in diameter of the benzylic substituents is about... 

Another interesting effect related to H3 receptors is its possible interference in the airway microvascular leakage (AML) induced by a variety of stimuli. Activation of H3 receptors inhibits NANC-induced leakage by reducing neuropeptides release from sensory fibers (Ichinose et al., 1990). Hence, H3 receptors may act as a safety device in asthmatic diseases to prevent, not only bronchoconstriction, but also increased airway permeability. On the other hand, it was also demonstrated that H3 receptor activation inhibits sympathetic tone, which, in turn, reduces antigen-induced AML (Danko et al., 1994). Therefore, the authors conclude that the blockade of H3 receptors may have therapeutic potential in inflammatory pulmonary... 

Membrane permeabilization activity of peptides is currently measured by the use of artificial membrane bilayers, such as liposomes or erythrocytes. The hposome leakage assay can be performed by using spectrofluorimetry with a concentration-dependent quenching of a dye (calcein, carboxyfluorescein) encapsulated in liposomes. Disruption of hposomes in the presence of peptide-inducing leakage will lead to an increase in the fluorescence intensity of the liposome solution. Erythrocyte lysis assay is based on the absorption of hemoglobin, which can be measured once released into the extracellular medium upon erythrocyte lysis in the presence of peptide. 

Although this was an essentially static model based on optimized interactions between the peptide and the phospholipids treated as rigid bodies, the results agreed well with experimental data, showing that increasing PG content in the membrane was paralleled with a nisin-induced leakage. 

Andersson, A., J. Danielsson, A. Graslund, and L. Maler (2007) Kinetic models for peptide-induced leakage from vesicles and cells. Eur. Biophys. J. 36, 621-635. 

Most CPPs are considered to display low toxicity and to be devoid of side effects in cultured cells. According to the MTT assay, the viability of different cell types in the presence of CPPs at 10 to 50 pM concentrations has been reported to be excellent (33). However, the amphipathic CPPs, especially MAP, induce leakage of the plasma membrane at concentrations below 5 pM (31). The toxicity of polyarginine peptides increases with the peptide length and polymers with molecular mass of 12 kDa are cytotoxic at concentrations less than 1 pM (34). 

To evaluate evaporative loss of fluid from the capillary gap, the instrument was programmed to dispense 100 )xL of colored tap water into the gaps created between coverplates and clean, blank slides. The waste tray was filled with 50 mL of water, and the instrument lid was closed. Slides were observed for a 2-h period, and fluid loss was assessed. For the first 60 min, there was no appreciable fluid loss. At 90 min, an average of 7 mm (fluid height in the gap) was lost. At 120 min, an average of 12 mm of fluid was lost. These measurements correspond to a total loss of fluid from the gap of 24% over the 2-h period. Whether the fluid loss was the result of evaporation or slow, gravity-induced leakage from the capillary gap was not assessed. 

Copeland, E.S., Alving, C.R., and Grenan, M.M. (1976) Light-induced leakage of spin label marker from liposomes in the presence of phototoxic phenothiazines, Photochem. Photobiol., 24, 41-48. 

P. Li. Critical path analysis considering temperature, power supply variations and temperature induced leakage. Proceedings of 2006 IEEE Inti. Symp. Quality Electronic Design, 2006. 

T. M. Allen, L. G. Cleland, Serum-induced leakage of hposome contents, Biochim. Biophys. Acta., 1980, 597, 418-426. 

Early on, pluronics were found to seal defects in phospholipid membranes, but mechanistic membrane studies did not begin until considerably later. One such study involves the examination of fibroblast cells loaded with a calcium-sensitive dye and wounded by tetanus toxin to induce leakage of the dye. Leakage reduced the fluorescence of the cells. The time required for the polymer to stop leaking dye was defined as the Tesealing time, from which a rate number is derived. The... 

The covalent attachment of PEAA to LUVs allowed the pH-induced leakage of calcein. This system was much more sensitive when compared to PEAA in solution. Fusion was suggested based on changes in fluorescence. The covalently attached PEAA induced 60-80% fiision compared to 30% when added to solution. 

A number of sesterterpenes from the genera Helminthospor-ium and Cochliobolus are phytoxins for their plant hosts. Ophiobolin A (105) is found in many species of these two genera. Ophiobolins induce chlorosis and necrosis of rice shoots and induce leakage of betacyanins from beet roots (Ballio, 1981). 

The risk of a disturbance to the SNF containers that may damage existing barriers, perhaps inducing leakage and weakening containment structures. 

Grunwald (1968, 1971) found that the ethanol- and methanol-induced leakage of plant tissues can be prevented by sterols. While free cholesterol was effective even at 0.1 ftM, concentrations of cholesteryl palmitate and cho-lesteryl glucoside at 0.1-100 ftM had no effect on the leakage. The actual penetration of these substances into the plasma membranes of plant cells would be worthy of study. 

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