Essential oils as phytochemical nematodicides with activity against plant parasitic nematodes

Synthetic pesticides used against plant parasitic nematodes (PPNs) have been discontinued due to serious environmental and public health concerns. Essential oils (EOs) are promising alternatives given they are easily accessible, show high biological activities, have low environmental impacts, and are subjected to less strict regulatory approval mechanismsWe reviewed the chemical composition of EOs with direct biological activity against the root-knot nematodes (RKNs), plant cyst nematodes (PCNs), and the pinewood nematode (PWN). The compositions (≥10%) of the top 10 most active EOs were compared

Biological interactions between nematophagous fungi, Esteya spp., and the pinewood nematode, Bursaphelenchus xylophilus

The pinewood nematode (PWN), Bursaphelenchus xylophilus, is a quarantine organism in several countries and the causal agent of pine wilt disease (PWD), a serious threat to pine forests worldwide. PWD results from complex interactions between the nematode, its insect vector, Monochamus spp., and host plants (conifers), being the nematode the common element in this interaction. The PWN is considered the sixth most economically important plant-parasitic nematode. In Europe, this pest was first reported in Portugal in 1999, in maritime pine, Pinus pinaster. Due to its economic importance and worldwide distribution, an enormous amount of effort is devoted to research on B. xylophilus and PWD. Scenarios strongly suggest that climate change is likely going to cause a spread of PWD and outbreaks in areas free of the disease. The urgent need for sustainable management strategies has led to an increasing interest in antagonists capable of suppressing the PWN. Nematophagous fungi belonging to the Esteya genus are reported as natural enemies of the PWN and promising biocontrol agents. There are currently two described species: E. vermicola and E. floridanum, the first of which is capable of mimicking volatile organic compounds produced naturally by Pinus spp. in order to attract PWN. However, few studies have been carried out on the development of Esteya spp. inside pine trees, and none using maritime pine, the main and most affected species in Portuguese forests and its largest carbon reservoir. It is therefore crucial to understand the plant-nematode-fungus interactions between P. pinaster, B. xylophilus and Esteya spp. In this sense, biological interactions between these two antagonists, the PWN and P. pinaster were investigated, namely fungus-fungus, fungus-nematode and fungus-tree, as well as feeding trials and chemotaxis assays, to determine the attractive power of both fungal species. These results will enlighten us on the most promising species for biocontrol and help us devise new ways to manage PWD

Nematode-Mycobiota interactions in Pine Wilt Disease

Pine wilt disease is one of the most important diseases for conifer forests worldwide. This complex disease involves the interaction between three primary biological elements - the plant parasitic nematode Bursaphelenchus xylophilus; the insect-vector Monochamus sp., and the host tree Pinus spp. – and other secondary elements such as endophytic bacteria and fungi. The development of B. xylophilus is strongly associated with fungi that colonize the declining trees, with special impact in their reproduction and number of individuals carried by the vector. In light of previous knowledge, we are focused in obtaining a detailed characterization of the structure and dynamics of the nematode-fungi interactions through culturable and non-culturable approaches with particular emphasis in metagenomics analysis. Our aim is to understand if nematode-associated mycobiota plays a key-role in the development of the disease, in interaction with nematode and insect-vector, and into which extend it can be used to disrupt the disease cycle

Cytotoxicity of the mycotoxins deoxynivalenol and ochratoxin A on Caco-2 cell line in presence of resveratrol

Exposure to mycotoxins through dietary food intake involves a highly complex scenario where co-contamination of different mycotoxins has been frequently demonstrated. On the other hand, the effect of the interaction of mycotoxins with other generally considered beneficial food components, as the antioxidants, has been scarcely studied. The main goal of the present work was to assess the cytotoxic effects on Caco-2 cells of the mycotoxins deoxynivalenol (DON) and ochratoxin A (OTA), alone or combined, and to explore potential protective effects of resveratrol (RES), an antioxidant frequently found in wine. In parallel, reactive oxygen species (ROS) production has also been studied as a first approach to understand the underlying mechanism of cytotoxicity. Results indicate a higher toxic effect of the mycotoxins when they are co-exposed. This increase in cytotoxicity was not accompanied by an increase in ROS production. The co-exposure of OTA or DON with RES did not result in a decrease in cytotoxicity; on the contrary, it resulted in increased cytotoxicity not associated with an increase in ROS production.The authors are grateful to the CYTED Action 109AC0371, to the INIA project (RTA 2012-00053-00-00) as well as the Spanish (Project AGL2011-24862) and Catalonian (XaRTA-Reference Network on Food Technology) Governments for their financial support. C.A. González-Arias thanks the Secretaria de Universitats i Recerca del Departament de Economia i Coneixement of the Generalitat de Catalunya for the pre-doctoral grant

Exponential energy decay of solutions for a system of viscoelastic wave equations of Kirchhoff type with strong damping

The initial boundary value problem for a system of viscoelastic wave equations of Kirchhoff type with strong damping is considered. We prove that, under suitable assumptions on relaxation functions and certain initial data, the decay rate of the solutions energy is exponential

Functional and molecular characterization of inherited platelet disorders in the Iberian Peninsula: results from a collaborative study

BACKGROUND: The diagnostic evaluation of inherited platelet disorders (IPDs) is complicated and time-consuming, resulting in a relevant number of undiagnosed and incorrectly classified patients. In order to evaluate the spectrum of IPDs in individuals with clinical suspicion of these disorders, and to provide a diagnostic tool to centers not having access to specific platelets studies, we established the project "Functional and Molecular Characterization of Patients with Inherited Platelet Disorders" under the scientific sponsorship of the Spanish Society of Thrombosis and Haemostasis. PATIENTS/METHODS: Subjects were patients from a prospective cohort of individuals referred for clinical suspicion of IPDs as well as healthy controls. Functional studies included light transmission aggregation, flow cytometry, and when indicated, Western-blot analysis of platelet glycoproteins, and clot retraction analysis. Genetic analysis was mainly performed by sequencing of coding regions and proximal regulatory regions of the genes of interest. RESULTS: Of the 70 cases referred for study, we functionally and molecularly characterized 12 patients with Glanzmann Thrombasthenia, 8 patients with Bernard Soulier syndrome, and 8 with other forms of IPDs. Twelve novel mutations were identified among these patients. The systematic study of patients revealed that almost one-third of patients had been previously misdiagnosed. CONCLUSIONS: Our study provides a global picture of the current limitations and access to the diagnosis of IPDs, identifies and confirms new genetic variants that cause these disorders, and emphasizes the need of creating reference centers that can help health care providers in the recognition of these defects

Profiling mycobiota communities associated with the Pine Wilt Disease

Pine wilt Disease (PWD) is one of the most damaging diseases for conifer forests worldwide. This complex disease involves the interaction between three primary biological elements - the pinewood nematode (PWN) Bursaphelenchus xylophilus, the insect-vector Monochamus sp., and the host tree Pinus spp. – and other secondary elements such as endophytic bacteria and fungi. The development of B. xylophilus is strongly associated with fungi that colonize the declining trees, with special impact in their reproduction and number of individuals carried by the vector. In light of previous knowledge, we are focused in obtaining a detailed characterization of the structure and dynamics of the nematode-fungi interactions. Using the ITS2 amplicon-based metagenomic approach, we compared the fungal communities from PWN infected and non-infected P. pinaster trees collected in two distint study sites, Tróia (location where PWN was first detected in 1999) and Seia (northwestern of Portugal)

Development of Cheaper Embryo Vitrification Device Using the Minimum Volume Method

[EN] This study was designed to compare the efficiency of the Cryotop and Calibrated plastic inoculation loop (CPIL) devices for vitrification of rabbit embryos on in vitro development and implantation rate, offspring rate at birth and embryonic and fetal losses. CPIL is a simple tool used mainly by microbiologists to retrieve an inoculum from a culture of microorganisms. In experiment 1, embryos were vitrified using a Cryotop device and a CPIL device. There were no significant differences in hatched/hatching blastocyst stage rates after 48 h of culture among the vitrified groups (62±4.7% and 62±4.9%, respectively); however, the rates were significantly lower (P<0.05) than those of the fresh group (95±3.4%). In experiment 2, vitrified embryos were transferred using laparoscopic technique. The number of implanted embryos was estimated by laparoscopy as number of implantation sites at day 14 of gestation. At birth, total offspring were recorded. Embryonic and fetal losses were calculated as the difference between implanted embryos and embryos transferred and total born at birth and implanted embryos, respectively. The rate of implantation and development to term was similar between both vitrification devices (56±7.2% and 50±6.8% for implantation rate and 40±7.1% and 35±6.5% for offspring rate at birth); but significantly lower than in the fresh group (78±6.6% for implantation rate and 70±7.2% for offspring rate at birth, P<0.05). Likewise, embryonic losses were similar between both vitrification devices (44±7.2% and 50±6.8%), but significantly higher than in the fresh group (23±6.6%, P < 0.05). However, fetal losses were similar between groups (10±4.4%, 15±4.8% and 8±4.2%, for vitrified, Cryotop or CPIL and fresh, respectively). These results indicate that the CPIL device is as effective as the Cryotop device for vitrification of rabbit embryos, but at a cost of 0.05 per device.This research was supported by the projects Spanish Research project AGL2014-53405-C2-1-P Comision Interministerial de Ciencia y Tecnologia (FMJ, JSV) and Generalitat Valenciana research program (Prometeo II 2014/036, JSV, FMJ).Marco Jiménez, F.; Jiménez Trigos, ME.; Almela-Miralles, V.; Vicente Antón, JS. (2016). Development of Cheaper Embryo Vitrification Device Using the Minimum Volume Method. PLoS ONE. 11(2):1-9. https://doi.org/10.1371/journal.pone.0148661S1911

Temporal resolution of protein–protein interactions in the live-cell plasma membrane

We have recently devised a method to quantify interactions between a membrane protein (“bait”) and a fluorophore-labeled protein (“prey”) directly in the live-cell plasma membrane (Schwarzenbacher et al. Nature Methods 5:1053–1060 2008). The idea is to seed cells on surfaces containing micro-patterned antibodies against the exoplasmic domain of the bait, and monitor the co-patterning of the fluorescent prey via fluorescence microscopy. Here, we characterized the time course of bait and prey micropattern formation upon seeding the cells onto the micro-biochip. Patterns were formed immediately after contact of the cells with the surface. Cells were able to migrate over the chip surface without affecting the micropattern contrast, which remained constant over hours. On single cells, bait contrast may be subject to fluctuations, indicating that the bait can be released from and recaptured on the micropatterns. We conclude that interaction studies can be performed at any time-point ranging from 5 min to several hours post seeding. Monitoring interactions with time opens up the possibility for new assays, which are briefly sketched in the discussion section