Implementation of an extended ZINB model in the study of low levels of natural gastrointestinal nematode infections in adult sheep

Background: In this study, two traits related with resistance to gastrointestinal nematodes (GIN) were measured in 529 adult sheep: faecal egg count (FEC) and activity of immunoglobulin A in plasma (IgA). In dry years, FEC can be very low in semi-extensive systems, such as the one studied here, which makes identifying animals that are resistant or susceptible to infection a difficult task. A zero inflated negative binomial model (ZINB) model was used to calculate the extent of zero inflation for FEC; the model was extended to include information from the IgA responses. Results: In this dataset, 64 % of animals had zero FEC while the ZINB model suggested that 38 % of sheep had not been recently infected with GIN. Therefore 26 % of sheep were predicted to be infected animals with egg counts that were zero or below the detection limit and likely to be relatively resistant to nematode infection. IgA activities of all animals were then used to decide which of the sheep with zero egg counts had been exposed and which sheep had not been recently exposed. Animals with zero FEC and high IgA activity were considered resistant while animals with zero FEC and low IgA activity were considered as not recently infected. For the animals considered as exposed to the infection, the correlations among the studied traits were estimated, and the influence of these traits on the discrimination between unexposed and infected animals was assessed. Conclusions: The model presented here improved the detection of infected animals with zero FEC. The correlations calculated here will be useful in the development of a reliable index of GIN resistance that could be of assistance for the study of host resistance in studies based on natural infection, especially in adult sheep, and also the design of breeding programs aimed at increasing resistance to parasites

Preservation of Quercus robur germplasm by cryostorage of embryogenic cultures derived from mature trees and rapd analysis of genetic stability

This study reports on the cryostorage of embryogenic lines derived from selected mature Quercus robur trees, following application of the PVS2-vitrification based procedure. In seven oak genotypes, embryo recovery levels ranging from 57-92% were obtained when 4-6 mg embryo clumps were precultured for 3 days on 0.3 M sucrose basal medium, treated with PVS2 solution for 60 min at 24ºC, and then immersed in liquid nitrogen (LN). Embryos of six out of seven lines were cryostored for one week and one year and used to evaluate cryopreservation tolerance, germination ability and to assess genetic fidelity by random amplified polymorphic DNA (RAPD) markers. There were no significant differences between the recovery frequencies of samples retrieved from LN after 1 week and 1 year of cryostorage. In five out of six lines, RAPD profiles of cryopreserved somatic embryos and regenerated plantlets were identical to those of the controls. Although polymorphisms were detected in only one cryostored embryo of one genotype, no genetic instability was found in the regenerated plantlets. This methodology appears to be suitable for long-term storage of this valuable germplasm, as the recovered plantlets were found to be genetically stable.Xunta de Galicia project: PGIDIT03RFO40001PR MEC (Spain) project: AGL2006-01387/FORPeer reviewe

Implementation of an extended ZINB model in the study of low levels of natural gastrointestinal nematode infections in adult sheep

[EN] Background: In this study, two traits related with resistance to gastrointestinal nematodes (GIN) were measured in 529 adult sheep: faecal egg count (FEC) and activity of immunoglobulin A in plasma (IgA). In dry years, FEC can be very low in semi-extensive systems, such as the one studied here, which makes identifying animals that are resistant or susceptible to infection a difficult task. A zero inflated negative binomial model (ZINB) model was used to calculate the extent of zero inflation for FEC; the model was extended to include information from the IgA responses. Results: In this dataset, 64 % of animals had zero FEC while the ZINB model suggested that 38 % of sheep had not been recently infected with GIN. Therefore 26 % of sheep were predicted to be infected animals with egg counts that were zero or below the detection limit and likely to be relatively resistant to nematode infection. IgA activities of all animals were then used to decide which of the sheep with zero egg counts had been exposed and which sheep had not been recently exposed. Animals with zero FEC and high IgA activity were considered resistant while animals with zero FEC and low IgA activity were considered as not recently infected. For the animals considered as exposed to the infection, the correlations among the studied traits were estimated, and the influence of these traits on the discrimination between unexposed and infected animals was assessed. Conclusions: The model presented here improved the detection of infected animals with zero FEC. The correlations calculated here will be useful in the development of a reliable index of GIN resistance that could be of assistance for the study of host resistance in studies based on natural infection, especially in adult sheep, and also the design of breeding programs aimed at increasing resistance to parasitesSIThis work was supported by a competitive grant from the Castilla and León regional government (Junta de Castilla y León) (Ref. LE245A12-2); the EC-funded Innovative Training Network (ITN) NematodeSystemHealth (M. A. and J. M. P., P7-KBBE-2009-3-245140); the BBSRC grant BB/L004004070/1; the Spanish “Ramón y Cajal” Programme from the Spanish Ministry of Economy and Competitiveness (B. G. G., RYC-2012-10230) and a postdoctoral Jae-Doc contract from the Consejo Superior de Investigaciones Científicas (CSIC) and co-funded by the European Social Fund (M. M. V.

The Puente Piedra Group in the Lima area and the demise of Jurassic arc volcanism along the Gondwana margin of Peru: The conundrum of The Oyotun Formation and its bewilldering correlation with the Misahualli Formation

The lower part of the Puente Piedra Group consists of thick bedded porphyritic to aphanitic basalts and basaltic andesite lava flows interbedded with medium bedded lithic to crystal lapilli tuffs known as the Tambo Inga Formation. The middle unit consists of varycolor tuffaceous shales interbedded with ash tuffs and thinly bedded fine grained lapilli tuffs that contain a rich Berriasian to Tithonian age fauna known as the Puente Inga Formation. The uppermost unit consists thick bedded massive porphyritic to aphanitic interbedded with coarse grained lapilli tuffs with rests of plants and well stratified pyroclastic breccias that toward the top contain abundant calcareous lapilli tuffs and recurrent varycolor tuffaceous shales that resemble the Middle unit and it is known as the Ventanilla Formation. Northward, between Piedras Gordas and Playa Ancon this unit is more than 1523 meters and it is dominated by porphyritic massive lava flows with abundant hyaloclastic breccias. The Puente Piedra Group and the correlative Oyotun and Guaneros formation documents the last stages of the Jurassic arc. Indeed, the Mesozoic arc initiated in Central Chile Margin during the Early Triassic continued throughout the Cretaceous along the Chilean margin. However; near the Peru-Chile border, this volcanic arc suddenly fades away during the Neocomian approach and subduction of an oceanic plateau. As a result, the subduction shallowed and was accompanied by extensional uplift of the Maranon and Paracas terranes and concomitant quartz-rich provenance change nourished by these terranes. Although, the Puente Piedra Group and the Guaneros and Oyotun formations have very similar normalized chondrite patterns that fluctuate from E-MORB and OIB caused by hyper-extension that boudinage the crust and brought up deeper fertile mantle during adiabatic decompression melting. However, while the Puente Piedra and Upper Guaneros have a gentle LREE slope and almost concave HREE with subtle negative Eu anomaly, the samples from the Oyoutun Formation have a spiky pattern with a distinctive signature branded by Tb-enrichment that it is difficult to explain (Fig. 1). Because of the pervasive intraplate extension coeval with enriched mantle upwelling, the Misahualli has similar chondrite pattern which perhaps was correlated with this unusual arc sequences. Indeed, while the Misahualli Formation was associated to a regional intraplate volcanism and extension prior to the opening of the South Atlantic, the Late Jurassic units along the coast of Peru were linked to a volcanic arc that underwent hyper-extension during oblique convergence. Finally, it is difficult to conceive a geotectonic correlation between the Misahualli Formation and the Jurassic Oyotun-Colan-Traposa formations. While the first unit has only been mapped east of the accreted Paleozoic terranes in Ecuador and it was developed during intraplate extension; the coastal units occurred only east of the Maranon Block and was part of a continental arc characterized by important E-MORB and OIB signatures. The broad variation in high in this diagram is related to removal of olivine, plagioclases and pyroxenes during fractionation and the relatively flat HREE perhaps reflects the absence of deep garnet. The normalized N-MORB diagram depicts a strong correlation between the Upper Guaneros and Oyotun formations with the Puente Piedra. The diagram shows a strong enrichment in LIL that is less pronounced in the Oyotun samples, however there is a slight depletion in the more HFS with higher enrichment in Pb and Sr and strong depletion in Nb typical of subduction related volcanic arcs

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Unusual Vermamoeba Vermiformis Strain Isolated from Snow in Mount Teide, Tenerife, Canary Islands, Spain

Background: Free-living amoebae (FLA) are protozoa that are widely distributed in the environment mainly in water and soil related habitats. Thermophilic amoebae are among the most common FLA in water bodies, being Vermamoeba vermiformis one of the most common species reported worldwide from these sources. Interestingly, V. vermiformis has often been reported to survive at high temperatures and osmotic pressure worldwide.Materials and Methods: In this study, snow samples were collected from Mount Teide, Tenerife, Canary Islands during the winter season of 2014. The samples were culture on non nutrient agar plates and checked daily for the presence of FLA. After a week, V. vermiformis amoebae were observed in the plates incubated at room temperature and 37ºC.Results: Molecular characterization was carried out by amplifying the 18S rDNA gene and DNA sequencing, confirmed that the isolated strain belonged to Vermamoeba vermiformis species.Conclusion: To the best of our knowledge, this is the first report of Vermamoeba vermiformis isolation from such an inusual habitat (low temperatures and high altitude) and the first report of these species in the Canary islands

Identification of compounds responsible for the anthelmintic effects of chicory (Cichorium intybus) by molecular networking and bio-guided fractionation

10 páginas, 7 figuras.Increasing resistance towards anthelmintic drugs has necessitated the search for alternative treatments for the control of gastrointestinal nematode parasites. Animals fed on chicory (Cichorium intybus L.), a temperate (pasture) crop, have reduced parasite burdens, hence making C. intybus a potentially useful source for novel anthelmintic compounds or a diet-based preventive/therapeutic option. Here, we utilized in vitro bioassays with the parasitic nematode Ascaris suum and molecular networking techniques with five chicory cultivars to identify putative active compounds. Network analysis predicted sesquiterpene lactones (SL) as the most likely group of anthelmintic compounds. Further bioassay-guided fractionation supported these predictions, and isolation of pure compounds demonstrated that the SL 8-deoxylactucin (8-DOL) is the compound most strongly associated with anti-parasitic activity. Furthermore, we showed that 8-DOL acts in a synergistic combination with other SL to exert the anti-parasitic effects. Finally, we established that chicory-derived extracts also showed activity against two ruminant nematodes (Teladorsagia circumcincta and Cooperia oncophora) in in vitro assays. Collectively, our results confirm the anti-parasitic activity of chicory against a range of nematodes, and pave the way for targeted extraction of active compounds or selective breeding of specific cultivars to optimize its future use in human and veterinary medicine.We are very grateful for the guidance and support by Dr. Thomas Ostenfeld Larsen and Christopher Phippen, Technical University of Denmark, Natural product discovery, and the laboratory assistance of Mette Schjelde, University of Copenhagen. This work was funded by the Danish Council for Independent Research (Grant DFF–6111-00394). Fractionation and purification of compounds were further supported by the Green Development and Demonstration Program (GUDP) (Project No. 34009-17-1220). MPE was supported by CONICYT Chile (FONDE-CYT Postdoctorado #317087

Effects of sardine-enriched diet on metabolic control, inflammation and gut microbiota in drug-naïve patients with type 2 diabetes: a pilot randomized trial.

Nutrition therapy is the cornerstone of treating diabetes mellitus. The inclusion of fish (particularly oily fish) at least two times per week is recommended by current international dietary guidelines for type 2 diabetes. In contrast to a large number of human studies examining the effects of oily fish on different cardiovascular risk factors, little research on this topic is available in patients with type 2 diabetes. The aims of this pilot study were to investigate the effects of a sardine-enriched diet on metabolic control, adiponectin, inflammatory markers, erythrocyte membrane fatty acid (EMFA) composition, and gut microbiota in drug-naïve patients with type 2 diabetes. 35 drug-naïve patients with type 2 diabetes were randomized to follow either a type 2 diabetes standard diet (control group: CG), or a standard diet enriched with 100 g of sardines 5 days a week (sardine group: SG) for 6 months. Anthropometric, dietary information, fasting glycated hemoglobin, glucose, insulin, adiponectin, inflammatory markers, EMFA and specific bacterial strains were determined before and after intervention. There were no significant differences in glycemic control between groups at the end of the study. Both groups decreased plasma insulin (SG: -35.3%, P = 0.01, CG: -22.6%, P = 0.02) and homeostasis model of assessment--insulin resistance (HOMA-IR) (SG: -39.2%, P = 0.007, CG: -21.8%, P = 0.04) at 6-months from baseline. However only SG increased adiponectin in plasma compared to baseline level (+40.7%, P = 0.04). The omega-3 index increased 2.6% in the SG compared to 0.6% in the CG (P = 0.001). Both dietary interventions decreased phylum Firmicutes (SG and CG: P = 0.04) and increased E. coli concentrations (SG: P = 0.01, CG: P = 0.03) at the end of the study from baseline, whereas SG decreased Firmicutes/Bacteroidetes ratio (P = 0.04) and increased Bacteroides-Prevotella (P = 0.004) compared to baseline. Although enriching diet with 100 g of sardines 5 days a week during 6 months to a type 2 diabetes standard diet seems to have neutral effects on glycemic control in drug-naïve patients with type 2 diabetes, this nutritional intervention could have beneficial effects on cardiovascular risk. Furthermore, both dietary interventions decreased HOMA-IR and altered gut microbiota composition of drug-naïve patients with type 2 diabetes. Trial number and name of the registry: NCT02294526, ClinicalTrials.gov

First Report of Vermamoeba vermiformis in the Island of El Hierro, Canary Islands, Spain

Background: Free-living amoebae (FLA) are group of protozoa distributed worldwide in many habitats mainly water and soil related sources. Some members of FLA are able to act as opportunistic pathogens and are environmental carriers of other pathogenic agents such as bacteria and viruses. Vermamoeba vermiformis is a highly abundant FLA species in water bodies and has recently gained environmental importance as it acts as a vehicle of many pathogenic bacteria such as Legionella pneumophila.Cases Report: In this study, water samples were collected from the island of El Hierro, Canary Islands, Spain during 2015. El Hierro island was designated by UNESCO as a biosphere reserve and it is currently the less populated of the Canary Islands. The water samples were culture on 2 % Non-Nutrient Agar (NNA) plates covered with a thin layer of heat killed E. coli and checked daily for the presence of FLA. After a week, V. vermiformis amoebae were observed in the plates incubated at room temperature and 37 ºC. Molecular characterization was carried out by amplifying the 18S rDNA gene and DNA sequencing, confirming that the isolated strain belonged to Vermamoeba vermiformis species.Conclusion: To the best of our knowledge, this is the first report of Vermamoeba vermiformis isolation in the island of El Hierro and the second report of this species in the Canary Islands