Phase specificity

Each of the above aspects shall now be treated individually in the sections that follows  

Broadly speaking the antineoplastic drugs may be categorized imder two heads, namely  

1 and 27.2 illustrate the cell-life cycle and the cell-cycle specificity respectively as given below  

S—DNA replication phase Gj—Resting phase Gj—Resting phase M—Mitosis phase 

Examples (a) Cancerous tumors having high growth fractions which are foimd to give adequate response to chemotherapy are, namely Hodgkin s disease, Burkitt s lymphoma, Wilm s tumour, acute leukemia in children, choriocarcinoma, chronic myelogenous leukemia, lymphocytic leukemia, and breast cancer. 

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Static This is a dense bed of solids in which each particle rests upon another at essentially the settled bulk density of the solids phase. Specifically, there is no relative motion among solids particles (Fig. 12-26). 

Figure 26-65 illustrates that Eq. (26-90) provides a linear approximation to the nonlinear relationship between two-phase specific volume and reciprocal pressure (v vs. P or vs. T ). For single components, me initial slope of the curve is found using me Clapeyron equation to give ... 

FIG. 26-65 Comp arison of predictions for two-phase specific volume as a function of pressure by the omega method for two alternative formulas to calculate omega. 

Nevertheless the spectra can give worthwhile evidence ofthe occurence and frequency of particular conformations of crystalline and glassy materials. However, the example of polyethylene shows that the MAS NMR technique does not offer this kind of information always and easily for the amorphous phase. Specific characteristics... 

Denef VJ, MA Patrauchan, C Florizone, J Park, TV Tsoi, W Verstraete, JM Tiedje, LD Eltis (2005) Growth substrate- and phase-specific expression of biphenyl, benzoate, and Cl metabolic pathways in Burkhold-eria xenovorans LB400. J Bacterial 187 7996-8005. 

The stimulant urge-impulses are seusitive to euviroumeutal cues such as retumiug home aud associated multiple situatioual stimuli (e.g., paraphernalia, friends, etc.). With continued drug availability, it is not unusual to observe repetitious cycles of bingeing with intervening crash and intermediate withdrawal phases over a period of months. It is noted that conditioned withdrawal responses are less pronounced than with opiates yet, withdrawal appears to have a phase-specific relation to the reemergence of cue-sensitive responses that deserves further research. 

The treatment of the two-phase SECM problem applicable to immiscible liquid-liquid systems, requires a consideration of mass transfer in both liquid phases, unless conditions are selected so that the phase that does not contain the tip (denoted as phase 2 throughout this chapter) can be assumed to be maintained at a constant composition. Many SECM experiments on liquid-liquid interfaces have therefore employed much higher concentrations of the reactant of interest in phase 2 compared to the phase containing the tip (phase 1), so that depletion and diffusional effects in phase 2 can be eliminated [18,47,48]. This has the advantage that simpler theoretical treatments can be used, but places obvious limitations on the range of conditions under which reactions can be studied. In this section we review SECM theory appropriate to liquid-liquid interfaces at the full level where there are no restrictions on either the concentrations or diffusion coefficients of the reactants in the two phases. Specific attention is given to SECM feedback [49] and SECMIT [9], which represent the most widely used modes of operation. The extension of the models described to other techniques, such as DPSC, is relatively straightforward. 

The study of separate mineral phases or of granulometric fractions is another approach which can be used to recover temporal information from radioactive disequilibria in weathering profiles. Such approaches rely on the assumption that the fractions only contain or concentrate minerals phases specific of a single or of few stages of formation and evolution of weathering profiles, and hence can help to characterise the time constants of the corresponding stages. 

Arion, D., Meijer, L., Brizuela, L., and Beach, D. (1988). cdc2 is a component of the M phase specific histone HI kinase evidence for identity withMPF. Cell 55 371-378. Balakier, H and Czolowska, R. (1977). Cytoplasmic control of nuclear maturation of mouse oocytes. Exp. Cell Res. 110 466-469. 

Gerhart, J., Wu, M., and Kirschner, M. (1984). Cell cycle dynamics of an M-phase-specific cytoplasmic factor in Xenopus laevis oocytes and eggs. J. Cell Biol. 98 1247-1255. 

In emulsion polymerization, a solution of monomer in one solvent forms droplets, suspended in a second, immiscible solvent. We often employ surfactants to stabilize the droplets through the formation of micelles containing pure monomer or a monomer in solution. Micelles assemble when amphiphilic surfactant molecules (containing both a hydrophobic and hydrophilic end) organize at a phase boundary so that their hydrophilic portion interacts with the hydrophilic component of the emulsion, while their hydrophobic part interacts with the hydrophobic portion of the emulsion. Figure 2.14 illustrates a micellized emulsion structure. To start the polymerization reaction, a phase-specific initiator or catalyst diffuses into the core of the droplets, starting the polymerization. 

This paper considers systems of lesser dimensionality than the previous study, namely, systems of two compounds, which (ignoring the vapor) can form only one or two phases. Specifically, excess enthalpies and phase compositions have been measured (at ambient pressure) by isoperibol calorimetry for n-butanol/water at 30.0 and 55.0 °C and for n-butoxyethanol/water at 55.0 and 65.0 °C. (Butanol, or C4E0, is C HgOH butoxyethanol, or C4E1, is C HgCX OH.) The miscibility... 

Costa M, Cantoni O, DeMars M, et al. 1982. Toxic metals produce S-phase-specific cell cycle block. Res Commun Chem Pathol Pharmacol 38 405-419. 

Appleton, J.A. and McGregor, D.D. (1985b) Life-phase specific induction and expression of rapid expulsion in rats suckling Trichinelki spiralis-infected dams. Immunology 55, 225—232. 

Bell, R.G., McGregor, D.D. and Despommier, D. (1979) Trichinella spiralis . Mediation of the intestinal component of protective immunity in the rat by multiple, phase-specific, antiparasitic responses. Experimental Parasitology 47, 140-157. 

Cytarabine -antimetabolite which is S-phase specific during DNA... 

Gemcitabine - nucleoside analogue antimetabolite S-phase specific cytotoxicity -bone marrow suppression—most commonly thrombocytopenia -nausea and vomiting -fever during administration -elevated transaminases -rash... 

Vinblastine -vinca alkaloid inhibits tubulin polymerization G2 phase specific -bone marrow suppression -vesicant if extravasated -nausea and vomiting -constipation (often secondary to neuropathy induced ileus) -neuropathy (jaw pain, peripheral neuropathy, autonomic neuropathy) -SIADH -tumor pain... 

The Lovelace work was later converted in Ref. 46 to scaled curves for combinations of peak incident overpressure and positive phase specific impulse. These curves are reproduced here as Fig. 40. Hirsch s work (Ref. 44) can also be given as pressure-impulse combinations for ear injury, and this also was done in Ref. 46. 

Equation (23-60) represents a linear relationship between the two- or three-phase specific volume and reciprocal pressure (v versus P 1 or Z... 

For multicomponent systems with boiling range greater than 80°C, a single adiabatic flash calculation to 80 to 90 percent of the inlet pressure P0 yields the two-phase specific volume oI at pressure P1 and co is calculated from (Nazario and Leung, Sizing Pressure Relief Valves in Flashing and Two-Phase Service An Alternative Procedure, J. Loss Prev. Process lnd. 5(5), pp. 263-269, 1992)... 

Specific separation effects can be understood from the multicomponent solubility parameter theory. Specific effects for nonpolar compounds are predictable with perfluorinated and graphitized carbon black stationary phases. Specific selectivity for polar compounds in reversed-phase HPLC can be realized with polar additives to the mobile phase. 

An interesting example of MIP-LC analytics was presented in a paper, which focused on the separation of antibiotics of similar structures. Columns are (commercially) available to separate penicillins ( 3-lactams) from other antibiotics. However, if the quantification of each of the 3-lactam compounds is required, a more selective stationary phase has to be found. Molecular imprinting allows the fabrication of phases specifically for each 3-lactam. If for instance the concentration of the P-lactam oxacillin in a food sample has to be selectively determined, a polymer imprinted with oxacillin is the right choice. Compared to a standard stationary phase, which only allowed the separation of the entire group of (5-lactams from other non-(3-lactam analytes (e. g., bacitracin), the MIP enables the separation of the imprinted species from the pair of non-imprinted 3-lactams penicillin V and penicillin G see Fig. 6 [29,30]. 

Sena G, Onado C, Cappella P, Montalenti F, Ubezio P. Measuring the complexity of cell cycle arrest and killing of drugs kinetics of phase-specific effects induced by taxol. Cytometry. 1999 Oct 1 37(2) 113-24. 

In addition to heterochromatic silencing, SUV39H1 H3 methyltransferase and HPl are involved in repression of euchromatic genes. The transcription factor E2F has a pivotal role in regulating the expression of S-phase-specific genes. Repression of these genes is through the retinoblastoma (Rb) protein which binds to E2F. 

The cytotoxic activity of cell cycle phase specific drugs (type II drugs) is time-dependent, and is different for cells in the sensitive phase (As) and in the resistant phase (Ar), as described as follows [2,27,28] ... 

The progression of the cell cycle is regulated by interconversion processes, in each phase, special Ser/Thr-specific protein kinases are formed, which are known as cyclin-depen-dent kinases (CDKs). This term is used because they have to bind an activator protein (cyclin) in order to become active. At each control point in the cycle, specific CDKs associate with equally phase-specific cyclins. if there are no problems (e.g., DNA damage), the CDK-cyclin complex is activated by phosphorylation and/or dephosphorylation. The activated complex in turn phosphorylates transcription factors, which finally lead to the formation of the proteins that are required in the cell cycle phase concerned (enzymes, cytoskeleton components, other CDKs, and cyclins). The activity of the CDK-cyclin complex is then terminated again by proteolytic cyclin degradation. 

Horton VL, Sleet RB,John-GreeneJA, etal Developmental phase-specific and dose-related teratogenic effects of ethylene glycol monomethyl ether in CD-I mice. Toxicol Appl Pharmacol 80 108-118, 1985... 

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