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Dopamine transmission in the prefrontal cortex (PFC) supports working memory (WM), the temporary holding, processing and manipulation of information in one's mind. The gene coding the catechol‐O‐methyltransferase (COMT) enzyme, which degrades dopamine, in particular in the PFC, has a common single nucleotide polymorphism leading to two versions of the COMT enzyme which vary in their enzymatic activity. The methionine (Met) allele has been associated with higher WM performance and lower activation of the PFC in executive function tasks than the valine (Val) allele. In a previous study, COMT genotype was associated with performance on verbal and visuospatial WM tasks in adults, as well as with performance on a novel social WM paradigm that requires participants to maintain and manipulate information about the traits of their friends or family over a delay. Here, data collected in children and adolescents (N = 202) were compared to data from the adult sample (N = 131) to investigate possible age differences in genetic associations. Our results replicate and extend previous work showing that the pattern of superior WM performance observed in Met/Met adults emerges during development. These findings are consistent with a decrease in prefrontal dopamine levels during adolescence. Developmentally moderated genetic effects were observed for both visuospatial and social WM, even when controlling for non‐social WM performance, suggesting that the maintenance and manipulation of social information may also recruit the dopamine neurotransmitter system. These findings show that development should be considered when trying to understand the impact of genetic polymorphisms on cognitive function., Rs4680 is a genetic polymorphism with two allelic variants (Met vs. Val) that affects the enzymatic activity of the catechol‐O‐methyltransferase (COMT) enzyme, which degrades dopamine. Met/Met adults have been found to have better performance and lower prefrontal cortex activity during working memory (WM) tasks. This study shows that the genetic association with visuospatial WM, but not verbal WM performance, emerges during development, and that the same pattern can be observed in a WM task requiring participants to manipulate social information. These results are consistent with a decrease in prefrontal dopamine levels during development and suggest an involvement of dopaminergic neurotransmission in social cognition.

Background and aim: Inflammation has been extensively implicated in the pathogenesis of Alzheimer’s disease (AD). Although there is evidence of a key role for cytokines in neuroinflammation processes, so far the proinflammatory cytokine interleukin (IL)-18 has not been associated with AD. The aim of this study was to investigate the impact of two polymorphisms of the human IL-18 gene promoter at positions −607 (C/A) and −137 (G/C) on both susceptibility to and progression of AD. Results: The results revealed that the genotype distribution of the −607 (C/A) polymorphism was different between patients with AD and control subjects (χ 2 = 7.99, df = 2, p = 0.0184). In particular, carriers of the CC genotype were at increased risk of developing AD (OR 2.33; 95% CI 1.29 to 4.22; p = 0.0052). The observed genotypes were in Hardy–Weinberg equilibrium, as for the −607 polymorphism, whereas the −137 polymorphism appeared in Hardy–Weinberg disequilibrium only in the patient group (p = 0.0061). Finally, in a 2 year follow-up study, the −137 CC genotype was strongly and specifically associated with a faster cognitive decline (F = 4.024; df = 4,192; p = 0.0037 for time by IL-18 −137 G/C group interaction) with no interaction effect with the apolipoprotein E e4/non-e4 allele presence. Conclusion: As IL-18 cytokine promoter gene polymorphisms have been previously described to have functional consequences on IL-18 expression, it is possible that individuals with a prevalent IL-18 gene variant have a dysregulated immune response, suggesting that IL-18 mediated immune mechanisms may play a crucial role in AD.

A well-known industrial fungus for enzyme production, Aspergillus niger, was selected to produce the feruloyl esterase FAEA by homologous overexpression for pulp bleaching application. The gpd gene promoter was used to drive FAEA expression. Changing the nature and concentration of the carbon source nature (maltose to glucose; from 2.5 to 60 g l-1), improved FAEA activity 24.5-fold and a yield of 1 g l-1 of the corresponding protein in the culture medium was achieved. The secreted FAEA was purified 3.5-fold to homogeneity in a two-step purification procedure with a recovery of 69%. The overproduced protein was characterised and presented properties in good agreement with those of native FAEA. The recombinant FAEA was tested for wheat straw pulp bleaching, with or without a laccase mediator system and xylanase. Best results were obtained using a bi-sequential process with a sequence including xylanase, FAEA and laccase, and yielded very efficient delignification - close to 75% - and a kappa number of 3.9. This is the first report on the potential application of recombinant FAEA in the pulp and paper sector. Chemicals/CAS: hemicellulose, 63100-39-0, 63100-40-3, 9034-32-6; laccase, 80498-15-3; xylan endo 1,3 beta xylosidase, 37278-89-0, 9025-55-2; Carboxylic Ester Hydrolases, EC 3.1.1.-; Endo-1,4-beta Xylanases, EC 3.2.1.8; feruloyl esterase, EC 3.1.1.73; Laccase, EC 1.10.3.2; Recombinant Proteins

Molecular genetic techniques were used to establish new characteristics in the animals and plants. Fishes are good animal protein resources and are suitable for genetic researches because of their short maturation time, high number of egg production in each spawning, and easy rearing. New characteristic can be establishes by it's related gene transfer. Transgenic researches in the fishes started about ten years ago. Different gene constructs were used in these researches. More than 60% of works were pure research to find the principal of gene transfers in the fishes. About 37.5% of research used growth hormone gene to improve fish growth; the rest of researches used anti-freeze protein gene. Adjustment of DNA forms, buffer contents transferring method for gene transfer are the main factors in the success of fish transgenic. There are different published researches to meet these problems in the last decade. In this paper these research is going to be reviewed and discussed......