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Alcohol dependence potentiates substance P/neurokinin-1 receptor signaling in the rat central nucleus of amygdala.
Behavioral and clinical studies suggest a critical role of substance P (SP)/neurokinin-1 receptor (NK-1R) signaling in alcohol dependence. Here, we examined regulation of GABA transmission in the medial subdivision of the central amygdala (CeM) by the SP/NK-1R system, and its neuroadaptation following chronic alcohol exposure. In naïve rats, SP increased action potential-dependent GABA release, and the selective NK-1R antagonist L822429 decreased it, demonstrating SP regulation of CeM activity under basal conditions. SP induced a larger GABA release in alcohol-dependent rats accompanied by decreased NK-1R expression compared to naïve controls, suggesting NK-1R hypersensitivity which persisted during protracted alcohol withdrawal. The NK-1R antagonist blocked acute alcohol-induced GABA release in alcohol-dependent and withdrawn but not in naïve rats, indicating that dependence engages the SP/NK-1R system to mediate acute effects of alcohol. Collectively, we report long-lasting CeA NK-1R hypersensitivity corroborating that NK-1Rs are promising targets for the treatment of alcohol use disorder
Application of microsatellite markers to parentage studies in grapevine
The use of microsatellites in genetic analysis does not only allow differentiation but also identification and parentage analysis of grapevine cultivars. Many of the cultivars which are of great economic importance, like Cabernet Sauvignon, have been selected and propagated centuries ago and often lack reliable documentation about their origins. In our study, 51 grapevine cultivars were genotyped at 24 microsatellite loci and searched for possible parent-offspring combinations. Our data confirm the origin of Cabernet Sauvignon from a cross between Cabernet franc and Sauvignon blanc. Furthermore we proved the parentage of the cultivars Neuburger (Silvaner x Veltliner rot), Blauburger (Portugieser blau x Blaufränkisch), Zweigelt (Blaufränkisch x St. Laurent) and Müller-Thurgau (Rheinriesling x Chasselas de Courtillier) at 24 SSR loci
Genetic characterization of Croatian grapevine cultivars and detection of synonymous cultivars in neighboring regions
Twenty-two native Croatian grapevine varieties representing three different growing and climatic regions (Dalmatia, Istria, continental Croatia) have been genotyped at nine SSR loci. The identical genotypes of the Croatian cultivars Plavina and Brajdica confirmed the hypothesis they are the same variety. Comparing the SSR profiles of the Croatian cultivars with the profiles stored in a database containing about 300 European cultivars, further three pairs of synonyms were revealed: Teran Bijeli shares its genotype with the Italian cultivar Prosecco, Muskat Ruza Porecki corresponds to cv. Rosenmuskateller from North Italy and Moslavac is identical to the Hungarian variety Furmint. The microsatellite-based definitions of these synonyms are strongly supported by ampelographic observations. The genetic variability within the investigated Croatian cultivars was high with a genetic diversity of 75 %. A dendrogram based on allele sharing distances reflected neither common morphological features nor common geographic origins of the cultivars
Genetic analysis of grape berries and raisins using microsatellite markers
Microsatellite markers have been used recently for the identification and pedigree analysis of grapevines with leaves and wood as sources of vine DNA. To identify grapes after harvest and their products, we applied DNA extraction protocols to grape berries and raisins. DNA was obtained from both sources, but that of raisins was highly degraded. The suitability of DNA for PCR amplification of single genetic loci was shown by amplification of 11 microsatellite markers. 18 commercially available table grape samples were genotyped, and 11 (61 %) matched the corresponding genetic profile in our reference database. Four samples were shown to be defined incorrectly and 4 samples did not match any of the generic profiles present in the database. The investigated raisins were found to be cv. Sultanina. The results demonstrate that DNA-based cultivar identification methods can be applied to harvested grapes and raisins
Synthetic enzymes for synthetic substrates
In recent years, hydrolases like cutinases, esterases and lipases have been recognized as powerful tools for hydrolysis of synthetic polymers such as polyethylene terephthalate (PET) as an environmentally friendly alternative for environmentally harmful chemical recycling methods1. PET is currently the most common type of aromatic polyester, with widespread application as packaging material, beverage bottles, and synthetic textile fibers. So far, cutinases have been the most active enzyme class regarding PET degradation. In nature, cutinases catalyze the hydrolysis of the aliphatic biopolyester cutin, the structural component of plant cuticle. Although cutinases are able to act on natural insoluble polyesters, their activities on non-natural substrates are quit low. For this reason, different engineering strategies were established to optimize “polyesterases” for synthetic polymers (Fig.1). Thereby, development of rationale enzyme-engineering strategies led to remarkable enhancement of hydrolytic activities on polyesters and clearly showed that the affinity between the enzyme and the substrate plays a key role in the enzymatic hydrolysis of synthetic polyester.
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Mycotoxin exposure and human cancer risk : a systematic review of epidemiological studies
In recent years, there has been an increasing interest in investigating the carcinogenicity of mycotoxins in humans. This systematic review aims to provide an overview of data linking exposure to different mycotoxins with human cancer risk. Publications (2019 and earlier) of case–control or longitudinal cohort studies were identified in PubMed and EMBASE. These articles were then screened by independent reviewers and their quality was assessed according to the Newcastle–Ottawa scale. Animal, cross‐sectional, and molecular studies satisfied criteria for exclusion. In total, 14 articles were included: 13 case–control studies and 1 longitudinal cohort study. Included articles focused on associations of mycotoxin exposure with primary liver, breast, and cervical cancer. Overall, a positive association between the consumption of aflatoxin‐contaminated foods and primary liver cancer risk was verified. Two case–control studies in Africa investigated the relationship between zearalenone and its metabolites and breast cancer risk, though conflicting results were reported. Two case–control studies investigated the association between hepatocellular carcinoma and fumonisin B1 exposure, but no significant associations were observed. This systematic review incorporates several clear observations of dose‐dependent associations between aflatoxins and liver cancer risk, in keeping with IARC Monograph conclusions. Only few human epidemiological studies investigated the associations between mycotoxin exposures and cancer risk. To close this gap, more in‐depth research is needed to unravel evidence for other common mycotoxins, such as deoxynivalenol and ochratoxin A. The link between mycotoxin exposures and cancer risk has mainly been established in experimental studies, and needs to be confirmed in human epidemiological studies to support the evidence‐based public health strategies
Carboxylation of phenols and asymmetric nucleophile addition across C=C bond
The regioselective carboxylation of electron-rich (hetero)aromatics employing decarboxylases in the redox-neutral (reverse) carboxylation reaction using bicarbonate or CO2(g) is currently exploited for the biocatalytic synthesis of carboxylic acids.1 Three enzyme classes exert complementary regioselectivities through diverse mechanisms: (i) Whereas the o-carboxylation of phenols (an equivalent to the Kolbe-Schmitt reaction) is mediated by Zn2+-dependent o-benzoic acid (de)carboxylases,2 (ii) the -carboxylation of hydroxystyrenes is catalysed by phenolic/ferulic acid (de)carboxylases acting via a pair of Tyr-Arg residues.3 (iii) Surpringly, these enzymes also exhibit a catalytic promiscuity for the nucleophile addition of H2O,4 NH2-OMe, cyanide and n-Pr-SH across the vinyl C=C bond via a quinone-methide intermediate, which yields the corresponding (S)-configurated adducts in up to 91% e.e.5 (iv) In search of ATP-independent regio-complementary p-benzoic acid (de)carboxylases, we discovered that 3,4-dihydroxybenzoic acid decarboxylase from Enterobacter cloacae6 (DHBDC_Ec) surprisingly depends on prenylated FMN7 as cofactor. In an attempt to propose a mechanism for the carboxylation of catechol by DHBDC_Ec, QM calculations revealed that the transient formation of a 1,3-dipolar cycloaddition product (as suggested for the decarboxylation of cinnamic acid with ferulic acid decarboxylase from S. cerevisiae8) was highly disfavored (\u3e30 kcal/M). As an alternative, we propose a mono-covalent nucleophile adduct involving a prFMN iminium electrophile (~14 kcal/M).
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Enzymatic surface hydrolysis of PET : effect of structural diversity on kinetic properties of cutinases from thermobifida
In this study cutinases from Thermobifida cellulosilytica DSM44535 (Thc_Cut1 and Thc_Cut2) and Thermobifida fusca DSM44342 (Thf42_Cut1) hydrolyzing poly(ethylene terephthalate) (PET) were successfully cloned and expressed in E.coli BL21-Gold(DE3). Their ability to hydrolyze PET was compared with other enzymes hydrolyzing natural polyesters, including the PHA depolymerase (ePhaZmcl) from Pseudomonas fluorescens and two cutinases from T. fusca KW3. The three isolated Thermobifida cutinases are very similar (only a maximum of 18 amino acid differences) but yet had different kinetic parameters on soluble substrates. Their kcat and Km values on pNP–acetate were in the ranges 2.4–211.9 s–1 and 127–200 μM while on pNP–butyrate they showed kcat and Km values between 5.3 and 195.1 s–1 and between 1483 and 2133 μM. Thc_Cut1 released highest amounts of MHET and terephthalic acid from PET and bis(benzoyloxyethyl) terephthalate (3PET) with the highest concomitant increase in PET hydrophilicity as indicated by water contact angle (WCA) decreases. FTIR-ATR analysis revealed an increase in the crystallinity index A1340/A1410 upon enzyme treatment and an increase of the amount of carboxylic and hydroxylic was measured using derivatization with 2-(bromomethyl)naphthalene. Modeling the covalently bound tetrahedral intermediate consisting of cutinase and 3PET indicated that the active site His-209 is in the proximity of the O of the substrate thus allowing hydrolysis. On the other hand, the models indicated that regions of Thc_Cut1 and Thc_Cut2 which differed in electrostatic and in hydrophobic surface properties were able to reach/interact with PET which may explain their different hydrolysis efficiencies.This study was performed within the Austrian Centre of Industrial Biotechnology ACIB, the MacroFun project and COST Action 868. This work has been supported by the Federal Ministry of Economy, Family and Youth (BMWFJ), the Federal Ministry of Traffic, Innovation and Technology (bmvit), the Styrian Business Promotion Agency SFG, the Standortagentur Tirol and ZIT - Technology Agency of the City of Vienna through the COMET-Funding Program managed by the Austrian Research Promotion Agency FFG. Financial support was also given from Sachsisches Staatsministerium fur Umwelt und Landwirtschaft, Germany. PET was kindly provided by Dr. Vincent Nierstrasz from Ghent University
Computers from plants we never made. Speculations
We discuss possible designs and prototypes of computing systems that could be
based on morphological development of roots, interaction of roots, and analog
electrical computation with plants, and plant-derived electronic components. In
morphological plant processors data are represented by initial configuration of
roots and configurations of sources of attractants and repellents; results of
computation are represented by topology of the roots' network. Computation is
implemented by the roots following gradients of attractants and repellents, as
well as interacting with each other. Problems solvable by plant roots, in
principle, include shortest-path, minimum spanning tree, Voronoi diagram,
-shapes, convex subdivision of concave polygons. Electrical properties
of plants can be modified by loading the plants with functional nanoparticles
or coating parts of plants of conductive polymers. Thus, we are in position to
make living variable resistors, capacitors, operational amplifiers,
multipliers, potentiometers and fixed-function generators. The electrically
modified plants can implement summation, integration with respect to time,
inversion, multiplication, exponentiation, logarithm, division. Mathematical
and engineering problems to be solved can be represented in plant root networks
of resistive or reaction elements. Developments in plant-based computing
architectures will trigger emergence of a unique community of biologists,
electronic engineering and computer scientists working together to produce
living electronic devices which future green computers will be made of.Comment: The chapter will be published in "Inspired by Nature. Computing
inspired by physics, chemistry and biology. Essays presented to Julian Miller
on the occasion of his 60th birthday", Editors: Susan Stepney and Andrew
Adamatzky (Springer, 2017
Narrow genetic base in forest restoration with holm oak (Quercus ilex L.) in Sicily
In order to empirically assess the effect of actual seed sampling strategy on
genetic diversity of holm oak (Quercus ilex) forestations in Sicily, we have
analysed the genetic composition of two seedling lots (nursery stock and
plantation) and their known natural seed origin stand by means of six nuclear
microsatellite loci. Significant reduction in genetic diversity and significant
difference in genetic composition of the seedling lots compared to the seed
origin stand were detected. The female and the total effective number of
parents were quantified by means of maternity assignment of seedlings and
temporal changes in allele frequencies. Extremely low effective maternity
numbers were estimated (Nfe 2-4) and estimates accounting for both
seed and pollen donors gave also low values (Ne 35-50). These values
can be explained by an inappropriate forestry seed harvest strategy limited to
a small number of spatially close trees
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