Thiamine pyrophosphate: An essential cofactor for the α-oxidation in mammals – implications for thiamine deficiencies?

The identification of 2-hydroxyphytanoyl-CoA lyase (2-HPCL), a thiamine pyrophosphate (TPP)-dependent peroxisomal enzyme involved in the α-oxidation of phytanic acid and of 2-hydroxy straight chain fatty acids, pointed towards a role of TPP in these processes. Until then, TPP had not been implicated in mammalian peroxisomal metabolism. The effect of thiamine deficiency on 2-HPCL and α-oxidation has not been studied, nor have possible adverse effects of deficient α-oxidation been considered in the pathogenesis of diseases associated with thiamine shortage, such as thiamine-responsive megaloblastic anemia (TRMA). Experiments with cultured cells and animal models showed that α-oxidation is controlled by the thiamine status of the cell/tissue/organism, and suggested that some pathological consequences of thiamine starvation could be related to impaired α-oxidation. Whereas accumulation of phytanic acid and/or 2-hydroxyfatty acids or their α-oxidation intermediates in TRMA patients given a normal supply of thiamine is unlikely, this may not be true when malnourished. Received 23 December 2005; received after revision 10 April 2006; accepted 28 April 2006     

Etude de la consommation d'oxygène et de la teneur en acide désoxyribonucléique du foie à divers âges chez le rat

Summary The quantitative study of whole liver DNA and liver nuclei DNA at various ages, and the simultaneous study of oxygen uptake shows the following facts:(1) The rate of oxygen consumption to the fresh weight or to the DNA or to diploid chromosomes group is the same for the adult or the young aged 8 days. The values of oxygen consumption calculated for one cell or for one nucleus (taking notice of the fact that the mean level of liver nuclei DNA varies with the age) at 8 days is only the half of the adult value. Even at two months the value is 20% lower than in the adult.(2) In older animals there is a decrease of oxygen uptake which is more noticeable on a cellular scale than with the classical rate to fresh or dry weight. We affirm the fact that the diminution of the oxygen uptake of each cell is compensated by the increase of the number of cells.     

Spatial quantum noise interferometry in expanding ultracold atom clouds

In a pioneering experiment, Hanbury Brown and Twiss (HBT) demonstrated that noise correlations could be used to probe the properties of a (bosonic) particle source through quantum statistics; the effect relies on quantum interference between possible detection paths for two indistinguishable particles. HBT correlations--together with their fermionic counterparts--find numerous applications, ranging from quantum optics to nuclear and elementary particle physics. Spatial HBT interferometry has been suggested as a means to probe hidden order in strongly correlated phases of ultracold atoms. Here we report such a measurement on the Mott insulator phase of a rubidium Bose gas as it is released from an optical lattice trap. We show that strong periodic quantum correlations exist between density fluctuations in the expanding atom cloud. These spatial correlations reflect the underlying ordering in the lattice, and find a natural interpretation in terms of a multiple-wave HBT interference effect. The method should provide a useful tool for identifying complex quantum phases of ultracold bosonic and fermionic atoms.     

Denitrifying bacteria of genus Alcaligenes isolated from soil]

The organism isolated is a small non-sporulating Gram-negative rod, motile by means of peritrichous flagellae. It is an oxidase-positive chemo-organotroph utilizing O2,NO-3,NO-2 and N2O as resiratory substrates. Primary alcohols as well as numerous organic and amino acids are utilized as carbon and energy sources. Carbohydrates are not assimilated. Poly-beta-hydroxybutyrate is accumulated intracellularly. The bacterium is assigned to the genus Alcaligenes and its phenotype characteristics are compared with those of A. faecalis.