Membrane interation

Kramer, S. D. Jakits-Deiser, C. Wunderli-Allenspach, H., Free-fatty acids cause pH-dependent changes in the drug-lipid membrane interations around the physiological pH,... 

The aforementioned studies employing various kinetic boundary conditions (uptake by the monolayers on a plastic substrate, efflux from the apical (AP) membrane of plastic-grown cells pre-equilibrated with drug, and efflux from the basolateral (BL) membrane of filter-grown cells pre-equilibrated with drug) permit the mechanistic and quantitative dissection of the kinetic process of apical-to-basolateral translocation of membrane-interative compounds in the presence and absence of BSA. The mathematical model for transmonolayer kinetics follows. 

Toxicity Cyto- Micro- topoiso- Telo- Membrane inter- DNA of protein... 

JW and JS stand for the solvent and solute membrane flux, respectively. A and B are the parameters related with the nature of the membrane material. AP, AX and AC, stand for the pressure difference, the osmotic pressure difference and the solute concentration difference between inside and outside of the membrane, respectively. The basic principle is to use the selective permeability of polymer membrane and the driving force of the concentration gradient, pressure gradient, the osmotic pressure gradient to transfer mass between the membrane inter-phase to achieve separation and purification of different components. Inorganic salts can pass through NF membrane. The osmotic pressure of NF membrane is lower than the RO membrane. 

D.W. Chen, Y.-H. Hsu, J.-Y. Liao, S.-J. Liu, J.-K. Chen, and S.W.-N. Ueng, Sustainable release of vancomycin, gentamicin and lidocaine from novel electrospun sandwich-structured PLGA/collagen nanofibrous membranes. Inter. J. Pharm., 430 (1-2), 335-341,2012. 

Cytochrome c 12.3 kDa 1 C type heme Inter membrane space, loosely associated with inner membrane 0.8-1.02 ... 

Figure 1. Immunofluorescent labeling of dystrophin in the Xp21 muscular dystrophies. In normal muscle, clear uniform labeling is present at the membrane of each muscle fiber. In Becker muscular dystrophy (BMD), there is inter- and intrafiber variation in labeling intensity. In Duchenne muscular dystrophy (DMD), most fibers are devoid of labeling (note, however, that in most biopsies occasional fibers exhibit weak labeling). In the biopsy from a manifesting carrier, some fibers show normal labeling and others are negative. In the former, the normal X-chromosome is active while in the latter the abnormal X-chromosome is active.

Various findings together suggest that organotins may have an effect at the level of the cell membrane and/or cytoskeleton, resulting in disturbances of inter-and intracellular communication processes, which are of crucial importance to thymocyte maturation (Pieters et al., 1994a). 

S-layer ultrafiltration membranes (SUMs) are isoporous structures with very sharp molecular exclusion limits (see Section III.B). SUMs were manufactured by depositing S-layer-carrying cell wall fragments of B. sphaericus CCM 2120 on commercial microfiltration membranes with a pore size up to 1 pm in a pressure-dependent process [73]. Mechanical and chemical resistance of these composite structures could be improved by introducing inter- and intramolecular covalent linkages between the individual S-layer subunits. The uni-... 

The above describes the major pathway of proteins destined for the mitochondrial matrix. However, certain proteins insert into the outer mitochoiidrial membrane facilitated by the TOM complex. Others stop in the intermembrane space, and some insert into the inner membrane. Yet others proceed into the matrix and then return to the inner membrane or intermembrane space. A number of proteins contain two signaling sequences—one to enter the mitochondrial matrix and the other to mediate subsequent relocation (eg, into the inner membrane). Certain mitochondrial proteins do not contain presequences (eg, cytochrome Cy which locates in the inter membrane space), and others contain internal presequences. Overall, proteins employ a variety of mechanisms and routes to attain their final destinations in mitochondria. 

Design parameters of the anode catalyst for the polymer electrolyte membrane fiiel cells were investigated in the aspect of active metal size and inter-metal distances. Various kinds of catalysts were prepared by using pretreated Ketjenblacks as support materials. The prepared electro-catalysts have the morphology such as the sizes of active metal are in the range from 2.0 to 2.8nm and the inter-metal distances are 5.0 to 14.2nm. The electro-catalysts were evaluated as an electrode of PEMFC. In Fig. 1, it looked as if there was a correlation between inter-metal distances and cell performance, i.e. the larger inter-metal distances are related to the inferior cell performance. 

Figure 2.9 Hyperpolarisation-activated cation current 4 and its role in pacemaking in a guinea-pig thalamic relay neuron. (Adapted from Figs 2 and 14 in McCormick, DA and Pape, H-C (1990) J. Physiol. 431 291-318. Reproduced by permission of the Physiological Society.) (a) Records showing the time-dependent activation of the h-current by hyperpolarisation and its deactivation on repolarising, (b) Interpretation of rhythmic activity in a thalamic relay neuron. (1) The inter-spike hyperpolarisation activates 7h to produce a slowly rising pacemaker depolarisation. (2) This opens T-type Ca " channels to give a more rapid depolarisation, leading to (3) a burst of Na" spikes (see Fig. 2.8). At (4) the depolarisation has closed (deactivated) the h-channels and has inactivated the T-channels. The membrane now hyperpolarises, assisted by outward K+ current (5). This hyperpolarisation now removes T-channel in-activation and activates 7h (6), to produce another pacemaker potential...

PRINCE R L and DICK I (1997) Oestrogen effects on calcium membrane transport a new view of the inter-relationship between oestrogen deficiency and age-related osteoporosis. Osteoporosis Int 7, S150-S154. 

Figure 18.6 Energetics of the ORR at the heme/Cu site of CcO the enzyme couples oxidation of ferroc3ftochrome c (standard potential about —250 mV all potentials are listed with respect to a normal hydrogen electrode) to reduction of O2 (standard potential at pH 7 800 mV). Of the 550 mV difference, only 100 mV is dissipated to drive the reaction 220 mV is expanded to translocate four protons from the basic matrix compartment to the acidic IMS (inter-membrane space). In addition 200 mV is converted into transmembrane electrostatic potential as ferroc3ftochrome is oxidized in the IMS, but the charge-compensating protons are taken from the matrix. The potentials are approximate.

The method utilizing ID NMR is simple and eonvenient. Henee the NMR method diseussed here ean be applied to the systematie investigation of the membrane irug inter-aetions, elosely related to the vital function in biomembranes. It is expected that the application can be extended to the lipid-peptide interaction and protein uptake. We are now applying the method to apolipoprotein binding with lipid bilayers and emulsions. Preferential protein binding sites in membranes can be specified by NMR on the molecular level. 

The images obtained from the SPAN module (Figure 4.6.3(c and d)) show completely different characteristics compared with those from the SMC module. Noticeable features are the dense and evenly packed capillary membranes and the lower quality and inhomogeneities in the images. As already discussed for the ID profile (Figure 4.6.2(b)), both intra- and inter-membrane flow seems unhindered... 

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