[en] Human paraoxonase 1 (PON1) is a lipoprotein-associated enzyme involved in the detoxification of organophosphate pesticides (OPs) by hydrolyzing the bioactive oxons. Polymorphisms of the PON1 gene are responsible for variation in the expression and catalytic activity of PON1 enzyme. In the present study, we have determined (a) the prevalence of two common PON1 polymorphisms, (b) the activity of PON1 and acetylcholinesterase enzymes, and (c) the influence of PON1 genotypes and phenotypes variation on DNA damage in workers exposed to OPs. We examined 230 subjects including 115 workers exposed to OPs and an equal number of normal healthy controls. The results revealed that PON1 activity toward paraoxon (179.19 ± 39.36 vs. 241.52 ± 42.32 nmol/min/ml in controls) and phenylacetate (112.74 ± 17.37 vs. 134.28 ± 25.49 μmol/min/ml in controls) was significantly lower in workers than in control subjects (p < 0.001). No significant difference was observed in the distribution of genotypes and allelic frequencies of PON1₁₉₂QR (Gln/Arg) and PON1₅₅LM (Leu/Met) in workers and control subjects (p > 0.05). The PON1 activity toward paraoxonase was found to be significantly higher in the R/R (Arg/Arg) genotypes than Q/R (Gln/Arg) and lowest in Q/Q (Gln/Gln) genotypes in both workers and control subjects (p < 0.001). For PON1₅₅LM (Leu/Met), PON1 activity toward paraoxonase was observed to be higher in individuals with L/L (Leu/Leu) genotypes and lowest in individuals with M/M (Met/Met) genotypes in both groups (p < 0.001). No influence of PON1 genotypes and phenotypes was seen on the activity of acetylcholinesterase and arylesterase. The DNA damage was observed to be significantly higher in workers than in control subjects (p < 0.05). Further, the individuals who showed least paraoxonase activity i.e., those with (Q/Q [Gln/Gln] and M/M [Met/Met]) genotypes showed significantly higher DNA damage compared to other isoforms in workers exposed to OPs (p < 0.05). The results indicate that the individuals with PON1 Q/Q and M/M genotypes are more susceptible toward genotoxicity. In conclusion, the study suggests wide variation in enzyme activities and DNA damage due to polymorphisms in PON1 gene, which might have an important role in the identification of individual risk factors in workers occupationally exposed to OPs.

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[en] Cuphea is a herbaceous summer annual plant native to Central America. Its seed oil contains high amounts of medium chain fatty acids, depending on the species with C8, C10 and C12, respectively, amounting to sometimes more than 80% of the total fatty acids. The report summarizes over 10 years' research on the domestication of this genus. From extensive tests on the production potentials, some of these on a worldwide scale, a few most promising genotypes of the section Heterodon have been selected from among 45 species and 180 accessions for further genetic improvements. Chemical mutagenesis was effective in promoting the domestication programme and mutants have been obtained with, e.g. non-sticky hairiness, monoculm stem, and determinate growth by stem fasciation. However, the most desired mutation to indehiscent fruits has not yet been discovered within the selected productive Cuphea species. This problem of early seed dispersal in Cuphea may alternatively necessitate technical solutions, which also have been developed with a vacuum picking machine for multiple harvests. From the findings presented, some general considerations are deduced regarding the mutability of traits characterizing interspecific variation as well as regarding the need for improving the genetic background of mutants by recurrent selection procedures. (author). 17 refs, 2 figs, 9 tabs

[en] Palmitic rich interesterified (IE) fats exert detrimental effects on atherogenicity in animals but less significant effects in animal and human plasma lipids. Thus, it is important to investigate the role IE fats on lipid sub- fractions and hepatic gene expression involved in lipoprotein regulation. F1B male Golden Syrian hamsters (Mesocricetus auratus) were fed high-fat diets ad libitum containing 0.1% dietary cholesterol and 30.0% energy from dietary fat, either native or IE fats namely palm olein (PO), chemically IE palm olein (CIEPO), sal fat blend (SFB) and chemically IE sal fat blend (CIESFB) for 12 weeks. Plasma lipid profiles, low density lipoprotein (LDL) and high density lipoprotein (HDL) sub-fractions and hepatic gene expression levels were determined. PO and CIEPO fed hamsters had 38% and 27% higher plasma HDL levels compared to SFB and CIESFB, respectively. Animals given PO diet had greater proportion of the larger HDL particles than SFB and CIESFB fed animals (p<0.05). Whereas, animals fed with SFB and CIESFB had greater proportion of larger LDL particles compared to both palmitic counterparts. All diets upregulated genes involved in liver fat accumulation such as CXCL16, VLDR and APO E. SFB diet showed significant (p<0.05) 16-fold upregulation in CXCL16 gene. Gene expression for ABCA1, APO A1 and CETP were upregulated all groups in response of reverse cholesterol transport (RCT). Palmitic-rich diets presented significant upregulation in APO A1 gene (p<0.05). LDL metabolism related genes such as LDLR, PCSK9, APO B, CYP7A1, PCSK9 were downregulated in all diets. In conclusion, native and IE saturated high-fat diets, induce liver steatosis in hamsters as shown in CXCL16, VLDLR and APOE expression. In this condition, cholesterol clearance via RCT was activated with expression of related genes such as ABCA1, LCAT, APO A1 and CETP. However, these effects on plasma level HDL cholesterol and large HDL sub-fractions were only seen in palmitic rich fats. Whereas, LDLR mediated cholesterol clearance was downregulated with suppression of LDLR gene with similar effects on plasma LDL in all diets. (author)

[en] In the medical field, the oxidation phenomenon is the source of several pathologies (diabetes, cystic fibrosis, cancers,...). The natural oxidants are used as food preserving and skin ageing moderators. Several plant extracts with antioxidant activity were studied, this important antioxidant activity is probably due to their richness of compounds: polyphenols, phenolic acids, tocopherols, carotenoids, flavonoids,... Many techniques for evaluation and reactional mechanism study of the antioxidative activity are used. After selection, extraction, fractionation, activity screening, chemical analyses of molecules contained in the best active extracts, biological properties research of isolated redox pharmacophore, we have : - determined the structure of active products by spectroscopy and chromatography; - studied the antioxidative properties by EPR and spin trapping of the obtained extracts and molecules. The results of this first part of our work consists in evaluating the antioxidative degree of a great number of natural active principles, extracted from moroccan plants and pur obtained products. The second part consists in studying the action mechanisms using the LDL labelling (F. M.)

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[en] Limnanthes (family Limnanthaceae) species are herbaceous winter annuals with seed oil consisting of a high proportion of long chain fatty acids (C₂₀, C₂₂) with many potential industrial uses. Domestication efforts have largely involved biosystematic studies on genetic resources, agronomic evaluation of yield and cultural practices, and population improvement using mass and family selection methods. Significant gains which have been made in seed yield and its various components clearly make it a promising new crop. However, a wide variety of intra- and interspecific hybrid materials have only now become available for basic genetic research and accelerated breeding work. A search for both naturally occurring and induced mutations for modifying plant architecture, seed retention and increased self-fertility is highly recommended in order to facilitate commercial production as well as further gains in yield and adaptability, utilizing a combination of Mendelian and biometrical approaches. In parallel with Cuphea and other industrial crop breeding experience, Limnanthes research clearly illustrates the need for sustained and larger investments, a broadbased scientific approach, and some serendipitous (e.g. marketing) developments. (author). 25 refs, 1 fig., 5 tabs

[en] We demonstrate spectra of slabs of plasmonic 1D nanostructures and show their ability to detect a specific binding of low-density lipoproteins. Optical spectra of the slabs exhibiting a spectrally sharp resonant peak have been analyzed numerically to demonstrate responses of biosensors under study. We show that the sensitivity to biomolecular binding can be considerably increased by utilizing magnetooptical materials as constituent element of plasmonic 1D nanostructures. (paper)

[en] Lipoprotein-associated phospholipase A₂ (Lp-PLA₂) is a crucial enzyme in atherosclerosis as a potential drug target. The most remarkable Lp-PLA₂ inhibitory drug is Darapladib. We determined the binding pose of Darapladib to Lp-PLA₂ through docking study. Darapladib formed two hydrogen bonding interactions with the side chain of Tyr160 and Gln352 and several pi-pi interactions with aromatic and aliphatic hydrophobic residues of Lp-PLA₂. It is known that the dietylpropan-amine moiety of Darapladib has influence on the improvement of its oral bioavailability and we supposed this in our docking results