234 research outputs found

    In-vitro application of a qatari burkholderia cepacia strain (QBC03) in the biocontrol of mycotoxigenic fungi and in the reduction of ochratoxin a biosynthesis by aspergillus carbonarius

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    Mycotoxins are secondary metabolites produced by certain filamentous fungi, causing human and animal health issues upon the ingestion of contaminated food and feed. Among the safest approaches to the control of mycotoxigenic fungi and mycotoxin detoxification is the application of microbial biocontrol agents. Burkholderia cepacia is known for producing metabolites active against a broad number of pathogenic fungi. In this study, the antifungal potential of a Qatari strain of Burkholderia cepacia (QBC03) was explored. QBC03 exhibited antifungal activity against a wide range of mycotoxigenic, as well as phytopathogenic, fungal genera and species. The QBC03 culture supernatant significantly inhibited the growth of Aspergillus carbonarius, Fusarium culmorum and Penicillium verrucosum in PDA medium, as well as A. carbonarius and P. verrucosum biomass in PDB medium. The QBC03 culture supernatant was found to dramatically reduce the synthesis of ochratoxin A (OTA) by A. carbonarius, in addition to inducing mycelia malformation. The antifungal activity of QBC03’s culture extract was retained following thermal treatment at 100 °C for 30 min. The findings of the present study advocate that QBC03 is a suitable biocontrol agent against toxigenic fungi, due to the inhibitory activity of its thermostable metabolites. View Full-TextFunding: Qatar National Research Fund (a member of Qatar Foundation) under National Priorities Research Program (NPRP) grant #NPRP8-392-4-003.Scopu

    New perspective for an old drug: Can naloxone be considered an antioxidant agent?

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    Background: Experimental evidence indicates that Naloxone (NLX) holds antioxidant properties. The present study aims at verifying the hypothesis that NLX could prevent oxidative stress induced by hydrogen peroxide (H2O2) in PC12 cells.Methods: To investigate the antioxidant effect of NLX, initially, we performed electrochemical experiments by means of platinum-based sensors in a cell-free system. Subsequently, NLX was tested in PC12 cells on H2O2induced overproduction of intracellular levels of reactive-oxygen-species (ROS), apoptosis, modification of cells' cycle distribution and damage of cells' plasma membrane.Results: This study reveals that NLX counteracts intracellular ROS production, reduces H2O2-induced apoptosis levels, and prevents the oxidative damage-dependent increases of the percentage of cells in G2/M phase. Likewise, NLX protects PC12 cells from H2O2- induced oxidative damage, by preventing the lactate dehydrogenase (LDH) release. Moreover, electrochemical experiments confirmed the antioxidant properties of NLX.Conclusion: Overall, these findings provide a starting point for studying further the protective effects of NLX on oxidative stress

    Simultaneous wireless and high-resolution detection of nucleus accumbens shell ethanol concentrations and free motion of rats upon voluntary ethanol intake

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    Highly sensitive detection of ethanol concentrations in discrete brain regions of rats voluntarily accessing ethanol, with high temporal resolution, would represent a source of greatly desirable data in studies devoted to understanding the kinetics of the neurobiological basis of ethanol's ability to impact behavior. In the present study, we present a series of experiments aiming to validate and apply an original high-tech implantable device, consisting of the coupling, for the first time, of an amperometric biosensor for brain ethanol detection, with a sensor for detecting the microvibrations of the animal. This device allows the real-time comparison between the ethanol intake, its cerebral concentrations, and their effect on the motion when the animal is in the condition of voluntary drinking. To this end, we assessed in vitro the efficiency of three different biosensor designs loading diverse alcohol oxidase enzymes (AOx) obtained from three different AOx-donor strains: Hansenula polymorpha, Candida boidinii, and Pichia pastoris. In vitro data disclosed that the devices loading H. polymorpha and C. boidinii were similarly efficient (respectively, linear region slope [LRS]: 1.98 ± 0.07 and 1.38 ± 0.04 nA/mM) but significantly less than the P. pastoris-loaded one (LRS: 7.57 ± 0.12 nA/mM). The in vivo results indicate that this last biosensor design detected the rise of ethanol in the nucleus accumbens shell (AcbSh) after 15 minutes of voluntary 10% ethanol solution intake. At the same time, the microvibration sensor detected a significant increase in the rat's motion signal. Notably, both the biosensor and microvibration sensor described similar and parallel time-dependent U-shaped curves, thus providing a highly sensitive and time-locked high-resolution detection of the neurochemical and behavioral kinetics upon voluntary ethanol intake. The results overall indicate that such a dual telemetry unit represents a powerful device which, implanted in different brain areas, may boost further investigations on the neurobiological mechanisms that underlie ethanol-induced motor activity and reward

    The transition of people’s preferences for the intervention of the government in the economy of re-unified Germany

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    Covering the first fifteen years immediately after German re- unification, this paper analyzes the people’s support to the transition. The focus is on individuals’ preferences for the intervention of the government in the economy and on the opinion about competition per se. Eastern German data are compared with Western German data. Using suitable data that allow for interpersonal comparisons, the paper shows that Eastern Germans have always preferred an intervention of the public hand in the economy deeper than Western Germans; these different positions have hardly converged during the examined period of time. However there are no significant differences with respect to how Germans perceive competition per se: it is considered as a good by the people living in both parts of the country.info:eu-repo/semantics/publishedVersio

    LRRK2 affects vesicle trafficking, neurotransmitter extracellular level and membrane receptor localization

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    The leucine-rich repeat kinase 2 (LRRK2) gene was found to play a role in the pathogenesis of both familial and sporadic Parkinson's disease (PD). LRRK2 encodes a large multi-domain protein that is expressed in different tissues. To date, the physiological and pathological functions of LRRK2 are not clearly defined. In this study we have explored the role of LRRK2 in controlling vesicle trafficking in different cellular or animal models and using various readouts. In neuronal cells, the presence of LRRK2(G2019S) pathological mutant determines increased extracellular dopamine levels either under basal conditions or upon nicotine stimulation. Moreover, mutant LRRK2 affects the levels of dopamine receptor D1 on the membrane surface in neuronal cells or animal models. Ultrastructural analysis of PC12-derived cells expressing mutant LRRK2(G2019S) shows an altered intracellular vesicle distribution. Taken together, our results point to the key role of LRRK2 to control vesicle trafficking in neuronal cells

    Pest categorisation of Xanthomonas citri pv. viticola

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    The EFSA Plant Health Panel performed a pest categorisation of Xanthomonas citri pv. viticola (Nayudu) Dye, a Gram-negative bacterium belonging to the Xanthomonadaceae family. The pathogen is a well-defined taxonomic unit and is the causal agent of the leaf spot and bacterial canker of Vitis vinifera. This bacterium is present in India and Brazil, where it affects table grape cultivation; the same pathogen is able to cause a disease on Azadirachta indica and on some weed species. Reports indicate that the bacterium is present in Thailand as well. The pathogen has never been reported from the EU territory and it is not included in EU Commission Implementing Regulation 2019/2072. The pathogen can be detected on its host plants using direct isolation, serological or PCR-based methods. Its identification is achieved using biochemical and nutritional assays, together with a multilocus sequence analysis based on seven housekeeping genes. The main pathway for the entry of the pathogen into the EU territory is plant propagation material. In the EU, there is large availability of host plants, with grapevine being one of the most important crops in Europe and more specifically in its Mediterranean areas. Since X. citri pv. viticola is only reported in tropical and subtropical areas (BSh and Aw climatic zones according to the Köppen–Geiger classification), there is uncertainty whether the climatic conditions in the EU territory are suitable for its establishment. Nevertheless, due to the great importance of grapevine for the EU agriculture, any disease outbreak may have a high-economic impact. Phytosanitary measures are available to prevent the introduction of the pathogen into the EU. X. citri pv. viticola satisfies the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest

    Pest categorisation of Pestalotiopsis microspora

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    Following an EFSA commodity risk assessment of bonsai plants (Pinus parviflora grafted on Pinus thunbergii) imported from China, the EFSA Plant Health Panel performed a pest categorisation of Pestalotiopsis microspora, a clearly defined plant pathogenic fungus of the family Pestalotiopsidaceae. The pathogen was reported on a wide range of monocotyledonous, dicotyledonous and gymnosperms, either cultivated or wild plant species, causing various symptoms such as leaf spot, leaf blight, scabby canker, fruit spot, pre- and post-harvest fruit rot and root rot. In addition, the fungus was reported as an endophyte on a wide range of asymptomatic plant species. This pest categorisation focuses on the hosts that are relevant for the EU and for which there is robust evidence that the pathogen was formally identified by a combination of morphology, pathogenicity and multilocus sequencing analyses. Pestalotiopsis microspora was reported in Africa, North, Central and South America, Asia and Oceania. In the EU, it was reported in the Netherlands. There is a key uncertainty on the geographical distribution of P. microspora worldwide and in the EU, because of the endophytic nature of the fungus, the lack of surveys, and because in the past, when molecular tools were not fully developed, the pathogen might have been misidentified as other Pestalotiopsis species or other members of the Pestalodiopsidaceae family based on morphology and pathogenicity tests. Pestalotiopsis microspora is not included in Commission Implementing Regulation (EU) 2019/2072. Plants for planting, fresh fruits, bark and wood of host plants as well as soil and other growing media associated with plant debris are the main pathways for the entry of the pathogen into the EU. Host availability and climate suitability in parts of the EU are favourable for the establishment and spread of the pathogen. The introduction and spread of the pathogen into the EU are expected to have an economic and environmental impact where susceptible hosts are grown. Phytosanitary measures are available to prevent the introduction and spread of the pathogen into the EU. Unless the restricted distribution in the EU is disproven, Pestalotiopsis microspora satisfies all the criteria that are within the remit of EFSA to assess for this species to be regarded as potential Union quarantine pest

    Pest categorisation of Plicosepalus acaciae

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    The EFSA Panel on Plant Health performed a pest categorisation of Plicosepalus acaciae (Zuccarini) Wiens & Polhill), the acacia strap flower, a hemiparasitic plant of the family Loranthaceae parasitising woody plants. Host plants include several species of the genera Vachellia, Tamarix and Ziziphus and various fruit crops. P. acaciae is present in the Middle East and Eastern Africa and is not known to occur in the EU. P. acaciae has a long flowering period of about 10 months, from June to April the following year, during which flowers are pollinated by insects and birds. P. acaciae produces single seeded red berries that are eaten by birds, which then disseminate the seeds. The only known bird observed to disseminate the seeds of P. acaciae is Pycnonotus xanthopygos, which has been recorded just once (Spain) but it is not established in the EU. P. acaciae could enter into the EU with host plants for planting. Host plants are present and suitable climatic conditions occur in parts of the EU. If a suitable bird would adapt to transfer the seeds, establishment and spread of P. acaciae within the EU would be possible. If P. acaciae would be able to establish and spread, impacts on some crop plants (e.g. Juglans regia, Ficus carica, Punica granatum, Pistacia vera), ornamental plants, as well as native vegetation could occur. P. acaciae fulfils the criteria that are within the remit of EFSA to assess for this species to be regarded as a potential Union quarantine pest. Uncertainty remains on bird species other than P. xanthopygos transferring P. acaciae, the magnitude of potential impacts and the host range

    Pest categorisation of carrot thin leaf virus

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    Following a request from the EU Commission, the EFSA Panel on Plant Health conducted a pest categorisation of carrot thin leaf virus (CTLV) for the EU territory. The identity of CTLV, a member of the genus Potyvirus (family Potyviridae), is well established and reliable detection methods are available. The pathogen is not included in the EU Commission Implementing Regulation 2019/2072. CTLV has been reported from the USA and Colombia. In the EU, the virus was reported in Germany and Slovenia and the NPPO of both countries confirmed these reports. No official national measures have been taken so far. In 2018, CTLV was reported from Greece on Torilis arvensis subsp. arvensis. Since then, no other reports exist. According to the NPPO, the virus did not establish in Greece. In natural conditions, CTLV infects plant species of the family Apiaceae (i.e., carrot, coriander, parsley and several wild weed species). The virus is transmitted in a non-persistent manner by the aphids Myzus persicae and Cavariella aegopodii, which are widely distributed in the EU. CTLV has been reported not to be transmitted by carrot seeds, while no information is available for the other hosts. Since transmission through seeds is not uncommon for potyvirids, it cannot be excluded that CTLV can be seed transmitted for some hosts. Plants for planting, including seeds for sowing, were identified as potential pathways for entry of CTLV into the EU. Cultivated and wild hosts of CTLV are distributed across the EU. Economic impact on the production of cultivated hosts is expected if further entry and spread in the EU occur. Phytosanitary measures are available to prevent further entry and spread of the virus on its cultivated hosts. Currently, CTLV does not fulfil the criterion of being absent or present with restricted distribution and under official control to be regarded as a potential Union quarantine pest, unless official control is implemented. This conclusion is associated with high uncertainty regarding the current virus distribution in the EU
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