Short-term handling of the slimming agent oleoyl-estrone in liposomes (Merlin-2) by the rat

Female adult rats were injected in the jugular vein with oleoyl-3H-estrone incorporated into liposomes. The label rapidly disappeared from the blood, being taken up by the tissues, mainly liver, spleen and lung, which filtered most of the label. However, many other tissues, such as the heart, brown adipose tissue, adrenals and visceral fat incorporated significant amounts of oleoyl-estrone. The analysis of the form in which the label remained 10 min after the injection showed that it was hydrolysed in a large proportion even in liver and lungs. However, in most tissues (brain, brown and white - periovaric - adipose tissues and ovaries), intact oleoyl-estrone accounted for less than one quarter of all tissue label, and less than 10% in the case of subcutaneous adipose tissue and uterus. This rapid destruction of oleoyl-estrone is in agreement with the active role of this compound in the control of body weight.     

Hybridized electronic states between CdSe nanoparticles and conjugated organic ligands: A theoretical and ultrafast photo-excited carrier dynamics study

Formation of densely packed thin films of semiconductor nanocrystals is advantageous for the exploitation of their unique optoelectronic properties for real-world applications. Here we investigate the fundamental role of the structure of the bridging ligand on the optoelectronic properties of the resulting hybrid film. In particular, we considered hybrid films formed using the same CdSe nanocrystals and two organic ligands that have the same bidentate dithiocarbamate binding moiety, but differ in their bridging structures, one bridged by ethylene, the other by phenylene that exhibits conjugation. Based on the results of photo-excited carrier dynamics experiments combined with theoretical calculations on the electronic states of bridged CdSe layers, we show that only the phenylene-based ligand presents a strong hybridization of the molecular HOMO state with CdSe layers, that is a marker of formation of an effective bridge. We argue that this hybridization spread favors the hopping of photo-excited carriers between nanocrystals, which may explain the reported larger photo-currents in phenylene-based hybrid films than those observed in ethylene-based ones.

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A strategic laboratory approach for the performance investigation of geogrids in flexible pavements

Nowadays, the increasing request in terms of road transport makes maintenance and rehabilitation of road infrastructures key tasks for road engineering. In recent years, numerous products/materials have been introduced on the market and can be used in combination or singly in order to extend pavement life and guarantee high performance. Among them, geosynthetics can play different roles in pavement structures, such as draining, reinforcement, filtering, separation, protection, and proofing. This research focuses on the validation of a strategic laboratory approach for the study of the mechanical performance of reinforced systems used in flexible pavements, combining repeated loading cycles in a four-point bending configuration with interlayer shear tests. This method can be used in further research analysis to compare unreinforced and reinforced double-layered systems. The results obtained in this investigation showed that the fiberglass grid used provides a relevant contribution to the performance of the asphalt concrete system studied.     

Tocotrienol-rich fraction from palm oil affects gene expression in tumors resulting from MCF-7 cell inoculation in athymic mice

It has recently been shown that tocotrienols are the components of vitamin E responsible for inhibiting the growth of human breast cancer cells in vitro, through an estrogen-independent mechanism. Although tocotrienols act on cell proliferation in a dose-dependent manner and can induce programmed cell death, no specific gene regulation has yet been identified. To investigate the molecular basis of the effect of tocotrienols, we injected MCF-7 breast cancer cells into athymic nude mice. Mice were fed orally with 1 mg/d of tocotrienol-rich fraction (TRF) for 20 wk. At end of the 20 wk, there was a significant delay in the onset, incidence, and size of the tumors in nude mice supplemented with TRF compared with the controls. At autopsy, the tumor tissue was excised and analyzed for gene expression by means of a cDNA array technique. Thirty out of 1176 genes were significantly affected. Ten genes were down-regulated and 20 genes up-regulated with respect to untreated animals, and some genes in particular were involved in regulating the immune system and its function. The expression of the interferon-inducible transmembrane protein-1 gene was significantly up-regulated in tumors excised from TRF-treated animals compared with control mice. Within the group of genes related to the immune system, we also found that the CD59 glycoprotein precursor gene was up-regulated. Among the functional class of intracellular transducers/effectors/modulators, the c-myc gene was significantly down-regulated in tumors by TRF treatment. Our observations indicate that TRF supplementation significantly and specifically affects MCF-7 cell response after tumor formation in vivo and therefore the host immune function. The observed effect on gene expression is possibly exerted independently from the antioxidant activity typical of this family of molecules.     

Endemic goiter in school children of Salta Province, Argentina

The Province of Salta, located in the northwest of Argentina, showed severe endemic goiter-cretinism. The purpose of our work, therefore, was to evaluate the results of the iodized salt prophylaxis measure implemented since 1963. In 1980-1981 the prevalence of goiter was determined in 16,935 school children whose ages ranged from four to 15 years. The urinary iodine/creatinine index was also determined in a subsample of 401 children. Findings revealed that the goiter prevalence in the Province was 16.1%. In 10 Departments of the Province, those with greater socioeconomic development and denser population, the prevalences found were below 10%, limit established as endemic. In the remaining 13 Departments, especially in those less developed--where mountainous regions make their access difficult and hence, their populations consume non-iodized salt obtained from natural salt basins--values exceeded this limit. The average ioduria was 104.0 micrograms I/g Cr, with 4.5% presenting values below 25 micrograms. After 20 years of prophylaxis, endemic goiter has therefore been partially eradicated. It is suggested, however, that consumption of iodized salt and, even the supply of iodized oil in those areas where prevalence is high, be recommended.     

Effect of the slimming agent oleoyl-estrone in liposomes on the body weight of rats fed a cafeteria diet

In previous studies we observed that inhibition of cyclic 3',5'-nucleotide phosphodiesterase (PDE) isozymes, namely isozyme PDE3, suppresses proliferation of rat renal glomerular mesangial cells in vitro and in vivo. To determine whether activation of the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signaling pathway coupled to specific PDE isozymes modulates accelerated proliferation of renal epithelial cells, we investigated the effect of selective PDE isozyme inhibition on renal epithelial cell proliferation induced in rats by injection of folic acid (FA). In extracts from suspensions of renal cortical tubules, cAMP was metabolized predominantly by isozyme PDE4; activity of PDE3 was about three times lower. The increase in proliferative activity of renal cortical tissue from FA-injected rats, evaluated by immunostaining with Mib-1 antibody, was limited to tubular epithelial cells. Administration of the PDE3 inhibitors cilostazol or cilostamide together with the PDE4 inhibitor rolipram blocked mitogenic synthesis of DNA, as determined by (3H)-thymidine incorporation into renal cortical DNA, in FA-treated rats. FA injection caused an increase of more than 10-fold in proliferating cell nuclear antigen (PCNA) in renal cortical tissue; administration of the potent PDE3 inhibitor lixazinone or, to a lesser degree, cilostazol suppressed these high PCNA levels, whereas rolipram alone had no effect. The results indicate that FA-stimulated in vivo proliferation of renal tubular epithelial cells is down-regulated by activation of a cAMP-PKA signaling pathway linked to PDE3 isozymes. These observations are consistent with the notion that negative crosstalk between cAMP signaling and mitogen-stimulated signaling pathways regulates mitogenesis of renal cells of different terminal differentiation, including tubular epithelial cells.     

Dynamics and characterization of yeasts during ripening of typical Italian dry-cured ham

The evolution of the yeast population during manufacturing and ripening of dry-cured Parma ham was investigated. Contamination levels ranged from 10(5) to 10(7) cfu/g on muscle surface, 10(4) to 10(6) cfu/g on covering fat and exceeded 10(7) cfu/g on spreadable fat mince ("sugna"). Two hundred and sixty one yeast isolates underwent identification test, showing that the predominant species of yeast population during the whole maturing process were Debaryomyces hansenii, Candida zeylanoides, Debaryomyces maramus, and to a lesser extent, Candida famata and Hyphopichia burtonii. The species Candida catenulata, Candida guilliermondii, Candida edax and other genera like Cryptococcus and Wingea were occasionally found. The yeast counts and species distribution changed according to the stage of processing and to the ham sampling location. At the end of the cold phase, the washing procedure was effective in lowering the yeast count in muscle and fat surface layers, but during the next ageing stages, yeast colonization of unskinned ham muscle increased again, though species distribution changed if compared to previous manufacturing phases. The ripening steps taken into account from the end of the cold phase to the final outcome, were always characterized by more than one yeast species, suggesting that yeasts other than Debaryomyces spp. could play a remarkable role on the sensory and safety properties of typical Italian dry-cured ham.