Purification of tapioca leaf rhodanese

Tapioca (Manihot esculenta, kekabu variety) leaf rhodanese was purified 7.8 fold by column chromatography on Sephadex G-10, acetone fractionation a     

Application of oligo-(14-amino-3,6,9,12-tetraoxatetradecanoic acid) lipid conjugates as steric barrier molecules in liposomal formulations.

Lipid conjugates of oligo-(14-amino-3,6,9,12-tetraoxatetradecanoic acid) (ATTAn) were synthesized as monodisperse analogues of poly(ethylene glycol) (PEG) derivatives used in liposomal drug delivery systems. The new lipids were shown to be at least equivalent to MePEGA-2000-DSPE in assays designed to evaluate the effectiveness of polymers as steric barrier molecules in liposomes. Liposomes containing 1-5% of ATTA8-DSPE (octamer) showed comparable long circulation behavior relative to PEG-2000-DSPE analogues. Surprisingly, the shorter ATTA4-DSPE (tetramer) appeared to be quite effective in reducing clearance. Liver enzyme levels and systemic single dose tolerability of ATTA8-DSPE liposomes were comparable to controls, suggesting that the new materials are nontoxic. Prolonged exposure of ATTA8-DSPE liposomes to splenocytes in vitro showed no evidence of mitogenicity relative to controls or MePEGA-2000-DSPE liposomes. ATTA8-DSPE was as effective as MePEGC-2000-DSPE in preventing complement activation by cationic liposome systems. Repeat dosage in vivo regimes in ICR mice using DSPC/cholesterol liposomes, with and without 5% ATTA8-DSPE and MePEGC-2000-DSPE, showed no evidence of enhanced clearance on successive doses. Splenocytes recovered after repeat doses showed no significant evidence of mitogenicity on restimulation with liposomes. Cellular differentiation and activation marker levels in splenocytes recovered after the fourth in vivo administration were at normal levels. These results suggest that ATTAn oligomers do not induce an immune response in isolation. It was demonstrated that ATTA8-DSPE could be used to replace PEG-lipids in the formulation of doxorubicin, plasmid DNA and oligonucleotides using a variety of formulation techniques. The study demonstrates that ATTAn oligomers can be safely and effectively used in place of poly(ethylene glycol) as well-defined biomaterials in liposomal applications where reproducible behavior is critical.     

Biotic elicitation at different feeding time in cell suspension cultures of Eurycoma longifolia Jack,a valuable medicinal plant,for enhancement of cytotoxic activity of bioactive compounds against human colon cancer cell line

In Vitro Cellular & Developmental Biology - Plant - The root extract of Eurycoma longifolia Jack has been shown to be effective against different type of cancers. Present study was carried out...     

Establishment of <Emphasis Type="Italic">Cyperus aromaticus</Emphasis> cell suspension cultures for the production of Juvenile hormone III

Cell suspension cultures of Cyperus aromaticus were established from the yellow friable callus derived from the root explants of in vitro plantlets. Four callus cell lines were selected based on their growth index from two populations of callus cultures originated from the mother plants grown in two different locations. The selected four cell lines (Z1, Z6, P4, P9) showed uniform cell growth but produced different amounts of juvenile hormone III (JHIII). The Z1 cell line possessed fast-growing characteristics, produced a high JHIII content, and was chosen as the elite cell line for an optimization study of C. aromaticus cell suspension cultures. An inoculum cell mass of 0.3 g from 12-d cultures in 30 ml culture medium was found to be the optimum inoculum size and culture age for establishing the cell suspension culture of C. aromaticus. MS basal medium supplemented with 4.5 mg/l 2,4-D and 5.5 mg/l NAA was found to be the best medium for production of maximum cell biomass and JHIII. These results indicated that JHIII can be produced from suspension culture of C. aromaticus using a single-stage cell-culture system.     

A dye-binding induced conformational transition of poly-(methacrylic acid) by Auramine O in aqueous solutions. I. Experimental results

Binding of auramine O to poly-(methacrylic acid) (PMA) has been established over a large range of C⁰_p/C⁰_d values using spectroscopic methods (UV absorption and visible fluorescence emission spectra), equilibrium and sedimentation dialysis, potentiometric and viscosimetric titrations. All the results show qualitative agreement with those obtained previously with the system crystal violet-PMA although the binding seems to be less strong for auramine O than for crystal violet. From dialysis experiments binding isotherms were obtained at three different degrees of neutralization α'; at α' = 0.10 the results could be fitted to a Langmuir isotherm but at α' equal to 0.40 and 0.65 deviations with respect to such an isotherm occur. The results of potentiometric and viscosimetric titrations confirm that the conformational transition which the dye-free PMA exhibits upon ionization is affected by the dye binding. The region in which the conformational transion occurs is broadened and is less sharply defined in the presence of auramine O.     

Estimation of prediction error variances via Monte Carlo sampling methods using different formulations of the prediction error variance

Calculation of the exact prediction error variance covariance matrix is often computationally too demanding, which limits its application in REML algorithms, the calculation of accuracies of estimated breeding values and the control of variance of response to selection. Alternatively Monte Carlo sampling can be used to calculate approximations of the prediction error variance, which converge to the true values if enough samples are used. However, in practical situations the number of samples, which are computationally feasible, is limited. The objective of this study was to compare the convergence rate of different formulations of the prediction error variance calculated using Monte Carlo sampling. Four of these formulations were published, four were corresponding alternative versions, and two were derived as part of this study. The different formulations had different convergence rates and these were shown to depend on the number of samples and on the level of prediction error variance. Four formulations were competitive and these made use of information on either the variance of the estimated breeding value and on the variance of the true breeding value minus the estimated breeding value or on the covariance between the true and estimated breeding values.