Background: The 5-year multilevel epidemiological IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) study, launched under the Sixth ...Framework Programme of the European Commission, aims at counteracting the epidemic of dietary- and lifestyle-induced adverse health effects in children. To reveal possible links between overweight/obesity in childhood with taste sensitivity and taste preferences, special procedures were developed for application at the European level. This paper presents these newly developed procedures. Methods: Testing procedures to assess taste sensitivity for sucrose, sodium chloride, caffeine and monosodium glutamate and taste preferences for sweet, flavour, salty, fatty and umami tastes were developed with 191 children from nursery schools and preschools in northern Germany. To assess test–retest reliability, Cohen's kappa was calculated. Results: The study shows that it is possible to assess taste sensitivity and taste preferences even in young children, provided the framework of the procedures applied is adapted to this scenario. Test–retest reliability was calculated for the procedures applied and the results show that they are very reliable for assessing taste preferences and taste sensitivity in young children. Conclusion: It is possible to assess taste sensitivity and taste preferences even in young children, provided the methods applied are adapted to the special requirements that working with young children entail.
To analyze free prostate-specific antigen (f-PSA) in sera from patients with prostate cancer (PCa) and benign prostatic hyperplasia (BPH), and to detect possible differences in subtypes as potential ...diagnostic parameters.
PSA was purified from sera by an immunoaffinity procedure developed on the basis of oriented antibody immobilization, and subjected to size exclusion chromatography (SEC), Western blotting, and N-terminal amino acid sequencing.
The novel procedure allowed the purification of PSA with high yield from sera containing PSA <10 ng/ml. SEC under nonreducing conditions as well as Western blots demonstrated the presence of several molecular forms of f-PSA. Three of the smaller polypeptides exhibited the N-terminal sequence of PSA while one represented the C-terminal fragment Lys(146)-Pro(237). Shortening of some polypeptides by the N-terminal amino acid Ile(1) suggestive of aminopeptidase action was also observed. No propeptide sequence could be detected, and none of the bands from patient sera reacted with antibodies raised against propeptide antigens. BPH sera expressed higher proportions of smaller PSA fragments per unit p33, and contained significant amounts of fragments <14,000 which appeared to be very low or absent from most PCa sera.
f-PSA as obtained from BPH and PCa sera represents a heterogeneous fraction. The major component (p33) is not in the nicked form and does not contain proPSA. Diagnostic potential could arise from the quantitative differences of the smaller PSA derivatives seen between PCa and BPH sera.
Despite its conservation in organisms from bacteria to human and its general requirement for transcriptional silencing in yeast, the function of the Sir2 protein is unknown. Here we show that Sir2 ...can transfer labeled phosphate from nicotinamide adenine dinucleotide to itself and histones in vitro. A modified form of Sir2, which results from its automodification activity, is specifically recognized by anti-mono-ADP-ribose antibodies, suggesting that Sir2 is an ADP-ribosyltransferase. Mutation of a phylogenetically invariant histidine residue in Sir2 abolishes both its enzymatic activity in vitro and its silencing functions in vivo. However, the mutant protein is associated with chromatin and other silencing factors in a manner similar to wild-type Sir2. These findings suggest that Sir2 contains an ADP-ribosyltransferase activity that is essential for its silencing function.
Cell wall polysaccharides from black currants and bilberries were characterised in three approaches. First, compositions of skin, pulp, and seeds show the distribution of polysaccharides over these ...tissues. A sequential extraction of cell wall material with different aqueous extractants informs about the extractability of the different polysaccharides, viz. pectins, hemicellulose, and cellulose. Finally, by isolation of cell wall polysaccharides from juice and press cakes obtained by the conventional juice manufacturing. The polysaccharide distribution was followed during juice processing. The main difference between bilberries and black currants is the dominant sugar residue in seeds: mannose for black currants and xylose for bilberries. Most of the hemicellulolytic sugars and cellulose can be found back in the press cake. The sugar composition of the press cake is similar to the composition of the residue after sequential extraction. Black currants contain more pectic sugars than bilberries. Consequently, a commercial enzyme used during processing releases more pectic material into the juice.
In unstimulated interphase bovine epithelial (MDBK) cells, both regulatory (R II) and catalytic (C) subunits of the type II enzyme of cAMP‐dependent protein kinase (cAMP‐dPK II) are associated with ...the Golgi complex. However, as demonstrated by indirect immunofluorescence microscopy, within 5 min after stimulation of adenylate cyclase by forskolin, the C subunit dissociates from the Golgi‐associated R II and becomes diffusely distributed. With increasing time of forskolin treatment, C subunits accumulate in the nucleus, while R II subunits remain associated with the Golgi complex. The effect of forskolin is rapidly reversible in that C subunits begin to reassociate with the Golgi complex within a few minutes after drug removal. C subunit translocations similar to those produced by forskolin also occur after treatment of MDBK cells with dibutyryl‐cAMP, confirming that the observed effects are most likely mediated by elevation of intracellular cAMP levels. These results suggest that nuclear translocation of activated protein kinase subunits may represent an important link between hormonal stimuli and physiological responses.
The subcellular distribution of the type II enzyme of cAMP-dependent protein kinase (cAMP-dPK II) in epithelial and fibroblastic cells was determined by indirect immunofluorescence microscopy. In ...interphase cells both regulatory (R II) and catalytic (C) subunits were concentrated in a perinuclear area. By comparison of the R II distribution with the location of a bona fide Golgi membrane constituent, this area was identified as the Golgi complex. The cytochemical localization of R II was confirmed by subcellular fractionation. In addition, cAMP-dPK II was associated with microtubule-organizing centers, in particular with mitotic spindle poles. These distributions of cAMP-dPK II probably represent important factors in mediating the effects of cAMP on basic cellular activities ranging from secretion and proliferation to cell shape and motility.
Antibodies against pig thymus poly(ADP-ribose) polymerase were obtained with enzyme-hemocyanin conjugates and used for immunoquantitation. The quick-blot procedure used allowed the determination of ...amounts as low as 1 ng of enzyme from whole cell trichloracetic acid precipitates. When applied to analysis of various human, rodent, and bovine cell types, surprisingly similar amounts of polymerase were found (1-5 ng of pig thymus polymerase equivalents/micrograms of DNA, 2 X 10(5) polymerase molecules/HeLa cell). Also, no significant difference was seen between normal and transformed cells. Polymerase tended to decline in several fibroblast cultures upon reaching confluency, which was not reflected by total polymerase activity. Divergence between total activity and immunogenic equivalents was also seen in alkylated cells and in rat liver treated with phenobarbital. Trichloroacetic acid-insoluble fractions dissolved in sodium dodecyl sulfate buffer could also be used to analyze, by Western blotting, the size distribution of poly(ADP-ribose) polymerase in vivo. Application to various cell types revealed that all mouse and rat cells tested had two immunogenic bands (116 and 98 kDa) of similar intensity. A highly conserved structure of poly(ADP-ribose) polymerase may be deduced from the existence of immunogenic and renaturable 116-kDa polypeptide bands even in the low eukaryotes Physarum polycephalum and Dictyostelium discoideum.
Rhamnogalacturonan II (RG II) can play an important role during processing of berries due to its enzyme resistance and its possible role as a pectic cross-linker. This article describes the presence ...of RG II in cell walls, in juice and in press cake of bilberries and black currants. RG II was identified and quantified via its diagnostic sugar residues. RG II, which was released from homogalacturonan, was probably present in its dimeric form in muro. Juice contained the free RG II dimer, while from press cake dimeric RG II was released by enzymatic degradation of homogalacturonan. A higher amount of RG II was present in juice than in press cake. During juice processing a cross-linker RG II might improve gel formation, which hinders the processability of berries. In addition, enzymes used during juice processing release dimeric RG II from pectin molecules and accumulate RG II in the juice.
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