Design of a Cryogenic Videocamera-Recorder and Image Processing System and Calculation of Volumes of Red Cells

Since Rowe reported that the storage technique for red cells at very low temperatures had been realized successfully (4, 5), many experts who work in the fields of cryobiology and medicine have turned their attention to this storage technique for tissues and organs (3). Since the first quantitative cryomicroscope was made successfully about 20 years ago (1), it has been possible to observe changes in shape and phase. Particularly the image processing technique has laid the foundation for quantitative analysis of the relationship between changes in shape and damage from freezing of cells and cooling rate and storage temperature. In this work, we constructed a system consisting of a cryomicroscope, a videocamera-recorder, and an image processor. We carried out many experiments with red cells in cold storage and have established a model for calculating the volumes of red cells. In our experiments we also dynamically traced the shape changes of cells with various experimental parameters.     

Analysis of the immunoadjuvant octadecyl tyrosine hydrochloride

A simple, rapid, high performance liquid chromatographic (HPLC) method for the analysis of the immunoadjuvant octadecyl tyrosine hydrochloride is described. The HPLC procedure can be applied to the direct determination of amino acid reactants present as contaminants in the adjuvant (tyrosine, ethyl tyrosine) and from this information the content of octadecanol reactant can be estimated. Further, these same determinations provide a means of monitoring immunoadjuvant stability in any vaccine preparation.     

The influence of polyunsaturated fatty acids on spermine inhibition of lipoperoxidation. Studies on liposomes prepared with microsomal and mitochondrial phospholipids of sea bass (Dicentrarchus labrax L.) and rat liver

1. Composition of phospholipids extracted from different organelles of European sea bass liver was determined and compared with that of phospholipids extracted from the same organelles of rat liver. 2. Spermine binding to the vesicles prepared from microsomal and mitochondrial phospholipids and their aggregation was studied: these parameters indicate that only the presence of acidic phospholipids and not their unsaturation was essential for polyamine action. 3. No correlation exists between polyunsaturated fatty acid and spermine inhibition of lipid peroxidation. In fact microsomal phospholipids, which have a low content of acidic phospholipids, and a prevalent presence of phosphatidylinositol, are not protected by spermine. 4. Mitochondrial phospholipids, which have high content of cardiolipin, elicit the capability of spermine to inhibit lipid peroxidation.     

Human MC4R variants affect endocytosis,trafficking and dimerization revealing multiple cellular mechanisms involved in weight regulation

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On the mechanism of inhibition of NADH oxidase by ubiquinone-3

The combined effects of rotenone and ubiquinone-3 on the kinetics of NADH dehydrogenase and NADH oxidase have been investigated. The two inhibitors do not show additivity; on the other hand, ubiquinone-3, when preincubated with the enzyme, partially removes rotenone sensitivity. The inhibition of NADH oxidase by ubiquinone-3 is the result of at least two combined effects: the competition of the less active ubiquinone-3 with endogenous ubiquinone-10 in the acceptor site of the dehydrogenase, and a nonspecific action on the structure of complex I. The latter effect is perhaps mediated by a physical change of the phospholipid bilayer similar to that observed with agents such as butanol, perturbing lipid-protein interactions in the membrane.     

Spontaneous sister chromatid exchange and chromosome aberration frequency in humans: the familial effect.

The possible effects of environmental and genetic factors on spontaneous frequencies of sister chromatid exchanges (SCEs) and cells with chromosome aberrations (CAs) in human lymphocytes were investigated by analysing 177 completed families (mother, father and at least one child). After removing the effects of methodological, biological and life-style factors by the use of multifactor analysis of variance (MANOVA), SCEs and CAs residuals were analysed by simple correlation analysis and principal component analysis. SCEs and CAs inter-familiar variability was higher than that found within families. A significant correlation was found between the average SCE frequencies shared by parents (the so-called 'midpoint parents', or 'midparent') and offspring (linear slope b=0.26+/-0.07, p<0.05), but also between mother and father (b=0.23+/-0.11, p<0.05) suggesting the presence of an effective environmental factor. The midparent-offspring correlation was found to be sustained by the mother-offspring relationship (b=0.28+/-0.08, p<0.05), being the father-offspring correlation not significant (b=0.16+/-0.11, p0.05). Concerning CAs, no statistically significant correlation between parents was found, but the strong relationship between mother and offspring was confirmed (b=0.468+/-0.11, p<0.001). The SCEs correlation between mother vs. offspring disappeared for older offspring (over 23 years old). The obtained findings strongly showed that the genetic make-up is barely detectable in the presence of domestic environment factors which are shown to play the major role in determining the interfamilial variability of SCE and CA in a general population. These results strengthen the suitability of the use of SCEs and CAs analysis in human cytogenetic surveillance for the detection of effective environmental factors.     

Coenzyme Q-3 as an antioxidant. Its effect on the composition and structural properties of phospholipid vesicles.

Coenzyme Q-3 incorporated into the lipid bilayer at physiological concentration provided an 80% inhibition of the lipid peroxidation induced by ferrous ions. In coenzyme Q-containing vesicles, the fluorescence lifetime and the fluorescence anisotropy decay of the probe, 1,6-diphenyl-1,3,5-hexatriene, were measured in order to find out if the presence of the quinone can cause variations in the membrane organization. Our data show that two distinct populations of the probe were present and that both populations were available to quenching by coenzyme Q. The overall effects of coenzyme Q on the static and dynamic properties of the model membranes were: a very small effect in the ordering of the fatty acid chain, and a more noticeable decrease of the probe correlation time and, therefore, an increase in membrane fluidity at increasing quinone concentration. When vesicles were peroxidized in the absence of the coenzyme Q, the fluidity markedly decreased; in its presence, the fluidity was nearly unchanged. The results suggest that the antioxidant properties of coenzyme Q can be ascribed to its ability to react with free radicals. The effect on the fluidity of the lipid bilayer might imply that a requisite for a molecule to act as an efficient antioxidant could be its ability to readily diffuse within the membrane.     

Incorporation of ubiquinones into lipid vesicles and inhibition of lipid peroxidation

Ubiquinone incorporation into vesicles to evaluate its antioxidative effect on lipid peroxidation has been studied. Only sonication and not vortication allows comparable incorporation patterns of the various ubiquinone homologues into lipid vesicles. The measure of malondialdehyde, a convenient index for determining the extent of autoxidation, shows that both the naturally occurring homologues and synthetic shorter-chain ones, also in the oxidized form, possess similar antioxidant efficiency.