Nematicidal effect of volatile organic compounds (VOCs) on the plant-parasitic nematode Meloidogyne javanica

Previous studies have demonstrated that volatile organic compounds (VOCs), produced by the yeast Saccharomyces cerevisiae, were able to inhibit the development of phytopathogenic fungi. In this context, the nematicidal potential of the synthetic mixture of VOCs, constituted of alcohols and esters, was evaluated for the control of the root-knot nematode Meloidogyne javanica, which causes losses to crops of high economic value. The fumigation of substrate containing second-stage juveniles with VOCs exhibited nematicidal effect higher than 30% for the lowest concentration tested (33.3 µL g-1 substrate), whereas at 66.6 and 133.3 µL g-1 substrate, the nematode mortality was 100%. The present results stimulate other studies on VOCs for nematode management.

Estudio de la presencia de peligros (aflatoxinas) y fraudes (uso no declarado de cereal transgénico) en el gofio producido en Gran Canaria

[ES] Todavía hoy, los cereales son en gran medida el alimento más importante de la humanidad. En las Islas Canarias existe un alimento muy típico elaborado a base de cereales tostados y molidos conocido como gofio, que ya era consumido por los primeros habitantes de las islas. Se considera como un alimento seguro por su baja humedad y por alcanzar temperaturas de 130ºC durante su elaboración. Sin embargo, puede contener sustancias tóxicas conocidas como micotoxinas y, por otro lado, es posible que se elabore gofio con productos transgénicos sin declararse en la etiqueta. Debido a la actual exigencia de los consumidores de productos de calidad, se consideró de interés hacer un estudio sobre la presencia de aflatoxinas (una clase de micotoxinas) y de transgénicos en el gofio comercializado en la isla de Gran Canaria.

Study of innovative methods of control in the cereal productive chain for the production of beer and spirits

Researches performed during the PhD course intended to assess innovative applications of near-infrared spectroscopy in reflectance (NIR) in the production chain of beer. The purpose is to measure by NIR the "malting quality" (MQ) parameter of barley, to monitor the malting process and to know if a certain type of barley is suitable for the production of beer and spirits. Moreover, NIR will be applied to monitor the brewing process. First of all, it was possible to check the quality of the raw materials like barley, maize and barley malt using a rapid, non-destructive and reliable method, with a low error of prediction. The more interesting result obtained at this level was that the repeatability of the NIR calibration models developed was comparable with the one of the reference method. Moreover, about malt, new kinds of validation were used in order to estimate the real predictive power of the proposed calibration models and to understand the long-term effects. Furthermore, the precision of all the calibration models developed for malt evaluation was estimated and statistically compared with the reference methods, with good results. Then, new calibration models were developed for monitoring the malting process, measuring the moisture content and other malt quality parameters during germination. Moreover it was possible to obtain by NIR an estimate of the "malting quality" (MQ) of barley and to predict whether if its germination will be rapid and uniform and if a certain type of barley is suitable for the production of beer and spirits. Finally, the NIR technique was applied to monitor the brewing process, using correlations between NIR spectra of beer and analytical parameters, and to assess beer quality. These innovative results are potentially very useful for the actors involved in the beer production chain, especially the calibration models suitable for the control of the malting process and for the assessment of the “malting quality” of barley, which need to be deepened in future studies.

The nematode parasite fauna in three odontocete species: Phocoena phocoena, Lagenorhynchus albirostris, Lagenorhynchus acutus from Northern Scotland and its relationships with diet composition

Food items and nematode parasites were identified from the stomachs of 42 individuals of Phocoena phocoena, 6 of Lagenorhynchus acutus and 8 of L. albirostris stranded off the coastal waters of Northern Scotland between 2004 and 2014. Post-mortem examinations have revealed heavy parasitic worm burdens. Four nematode species complex as Anisakis spp., Contracaeucum spp., Pseudoterronova spp., and Hysterothylacium spp. were recorded. Data on presence of the anisakid species in cetaceans, reported a significative relationship between the presence of Hysterothylacium and the month of host stranding; suggesting a decrease of larval H. aduncum abundance in the period between April and August due to a seasonal effect related to prey availability. Similarly, the parasite burden of the all anisakid genera was related to the year fraction of stranding, and a relationship statistically significant was found just for L. albirostris with an increase between April and October. This finding is explained by a seasonality in occurrence of white-beaked dolphins, with a peak during August, that might be related to movements of shared prey species and competition with other species (Tursiops truncatus). Geographical differences were observed in parasites number of all anisakid species, which was the highest in cetaceans from the East area and lowest in the North coast. The parasites number also increased significantly with the length of the animal and during the year, but with a significant seasonal pattern only for P. phocoena. Regarding diet composition, through a data set consisting of 34 harbour porpoises and 1 Atlantic white-sided dolphins, we found a positive association between parasite number and the cephalopods genus Alloteuthis. This higher level of parasite infection in squid from this area, is probably due to a quantitative distribution of infective forms in squid prey, an abundance of the final host and age or size maturity of squid.

Cerebral air embolism caused by a bronchogenic cyst

An unusual case is presented of a tourist who developed fatal cerebral air embolism, pneumomediastinum and pneumopericardium while ascending from low altitude to Europe's highest railway station. Presumably the air embolism originated from rupture of the unsuspected bronchogenic cyst as a result of pressure changes during the ascent. Cerebral air embolism has been observed during surgery, in scuba diving accidents, submarine escapes and less frequently during exposure to very high altitude. People with known bronchogenic cysts should be informed about the risk of cerebral air embolism and surgical removal should be considered. Cerebral air embolism is a rare cause of coma and stroke in all activities with rapid air pressure changes, including alpine tourism, as our unfortunate tourist illustrates.

VHL-gene deletion in single renal tubular epithelial cells and renal tubular cysts: further evidence for a cyst-dependent progression pathway of clear cell renal carcinoma in von Hippel-Lindau disease

Inheritance of a mutant allele of the von Hippel-Lindau tumor suppressor gene predisposes affected individuals to develop renal cysts and clear cell renal cell carcinoma. Von Hippel-Lindau gene inactivation in single renal tubular cells has indirectly been showed by immunohistochemical staining for the hypoxia-inducible factor alpha target gene product carbonic anhydrase IX. In this study we were able to show von Hippel-Lindau gene deletion in carbonic anhydrase IX positive nonneoplastic renal tubular cells, in epithelial cells lining renal cysts and in a clear cell renal cell carcinoma of a von Hippel-Lindau patient. This was carried out by means of laser confocal microscopy and immunohistochemistry in combination with fluorescence in situ hybridization. Carbonic anhydrase IX negative normal renal tubular cells carried no von Hippel-Lindau gene deletion. Furthermore, recent studies have indicated that the von Hippel-Lindau gene product is necessary for the maintenance of primary cilia stability in renal epithelial cells and that disruption of the cilia structure by von Hippel-Lindau gene inactivation induces renal cyst formation. In our study, we show a significant shortening of primary cilia in epithelial cells lining renal cysts, whereas, single tubular cells with a von Hippel-Lindau gene deletion display to a far lesser extent signs of cilia shortening. Our in vivo results support a model in which renal cysts represent precursor lesions for clear cell renal cell carcinoma and arise from single renal tubular epithelial cells owing to von Hippel-Lindau gene deletion.

Trichilemmal cyst nevus with a sebaceous nevus component

A 23-year-old man with a typical trichilemmal cyst nevus is reported. This recently described disorder is sufficiently characteristic to differentiate it from sebaceous nevus, nevus comedonicus, porokeratotic eccrine nevus, nevus corniculatus, follicular basaloid hamartoma, Munro's nevus and Gardner's syndrome.

Monepantel allosterically activates DEG-3/DES-2 channels of the gastrointestinal nematode Haemonchus contortus

Monepantel is the first drug of a new family of anthelmintics, the amino acetonitrile derivatives (AAD), presently used to treat ruminants infected with gastrointestinal nematodes such as Haemonchus contortus. Monepantel shows an excellent tolerability in mammals and is active against multidrug-resistant parasites, indicating that its molecular target is absent or inaccessible in the host and is different from those of the classic anthelmintics. Genetic approaches with mutant nematodes have suggested acetylcholine receptors of the DEG-3 subfamily as the targets of AADs, an enigmatic clade of ligand-gated ion channels that is specific to nematodes and does not occur in mammals. Here we demonstrate direct interaction of monepantel, its major active metabolite monepantel sulfone, and other AADs with potential targets of the DEG-3 subfamily of acetylcholine receptors. H. contortus DEG-3/DES-2 receptors were functionally expressed in Xenopus laevis oocytes and were found to be preferentially activated by choline, to permeate monovalent cations, and to a smaller extent, calcium ions. Although monepantel and monepantel sulfone did not activate the channels by themselves, they substantially enhanced the late currents after activation of the channels with choline, indicating that these AADs are type II positive allosteric modulators of H. contortus DEG-3/DES-2 channels. It is noteworthy that the R-enantiomer of monepantel, which is inactive as an anthelmintic, inhibited the late currents after stimulation of H. contortus DEG-3/DES-2 receptors with choline. In summary, we present the first direct evidence for interaction of AADs with DEG-3-type acetylcholine receptors and discuss these findings in the context of anthelmintic action of AADs.

The nasopalatine duct cyst: an analysis of the relation between clinical symptoms, cyst dimensions, and involvement of neighboring anatomical structures using cone beam computed tomography

This study evaluates the dimensions of nasopalatine duct cysts (NPDCs) and the involvement of neighboring anatomical structures using standardized limited cone beam computed tomography (CBCT) and a possible correlation to the patient's age, gender, preoperative symptoms, and postsurgical complications.

Molecular characterization of Neospora caninum MAG1, a dense granule protein secreted into the parasitophorous vacuole, and associated with the cyst wall and the cyst matrix

SUMMARY: In Neospora caninum and Toxoplasma gondii, the parasitophorous vacuole (PV) is synthesized at the time of infection. During tachyzoite-to-bradyzoite stage conversion, the PV is later transformed into a tissue cyst that allows parasites to survive in their host for extended periods of time. We report on the characterization of NcMAG1, the N. caninum orthologue of T. gondii MAG1 (matrix antigen 1; TgMAG1). The 456 amino acid predicted NcMAG1 protein is 54% identical to TgMAG1. By immunoblotting, a rabbit antiserum raised against recombinant NcMAG1 detected a major product of approximately 67 kDa in extracts of N. caninum tachyzoite-infected Vero cells, which was stained more prominently in extracts of infected Vero cells treated to induce in vitro bradyzoite conversion. Immunofluorescence and TEM localized the protein mainly within the cyst wall and the cyst matrix. In both tachyzoites and bradyzoites, NcMAG1 was associated with the parasite dense granules. Comparison between NcMAG1 and TgMAG1 amino acid sequences revealed that the C-terminal conserved regions exhibit 66% identity, while the N-terminal variable regions exhibit only 32% identity. Antibodies against NcMAG1-conserved region cross-reacted with the orthologuous protein in T. gondii but those against the variable region did not. This indicates that the variable region possesses unique antigenic characteristics.