In vitro susceptibility of ten Haemonchus contortus isolates from different geographical origins towards acetone:water extracts of two tannin rich plants

The aim of the study was to examine the variation in the in vitro susceptibility of ten Haemonchus contortus isolates from different geographical origins using respective egg hatch assays (EHA) with acetone:water extracts of two tannin containing plants, chimay (Acacia pennatula) and sainfoin (Onobrychis viciifolia). Fresh eggs were incubated in PBS with different concentrations of each extract (0, 600, 1200, 2400, 3600, 5000 and 8000μg/ml PBS). Additional concentrations were tested for O. viciifolia (75, 100, 200 and 400μg/ml PBS). Effective concentrations 50% (EC50), with the corresponding 95% confidence interval (95% CI), were calculated for every isolate with both extracts. Moreover, a resistance ratio (RR) was calculated to compare the isolates, using the most susceptible isolate for each extract as the respective reference. A second set of incubations were made using polyvinylpolypyrrolidone (PVPP) (0, 5000μg/ml, 5000μg/ml+PVPP) to determine the influence of polyphenols on the AH effect. The proportion of morulated eggs, eggs with L1 larvae failing eclosion (%LFE), and emerged larvae were estimated at different extract concentrations. Data of each isolate was used to calculate the effective concentration 50% (EC50) for each extract. The EC50 of each isolate was used to determine resistance ratio (RR) for the different isolates. For the 2 extracts, a susceptibility variation in egg hatching was observed for the different H. contortus isolates. The EC50 values for A. pennatula ranged from 2203 to 14106μg (RR from 2.01 to 6.40). The O. viciifolia extract showed higher variability with EC50 values ranging from 104 to 4783μg (RR from 3.66 to 45.74). The main AH effects of the two extracts tested on the ten isolates consisted in blocking the emergence of L1 larvae (higher% LFE). Additional observations on emerged larvae showed that extract exposure caused alterations in the internal structure, separating the cuticle from the pharynx, bulb and intestinal cells. The use of PVPP revealed that (a) condensed tannins were not the sole plant secondary metabolites responsible for the AH effects, and (b) different H. contortus isolates showed variability in the role of tannins either on the ovicidal effect or the %LFE

Susceptibility of ten Haemonchus contortus isolates from different geographical origins towards acetone:water extracts of polyphenol-rich plants. Part 2: Infective L 3 larvae

This study explored the variation in susceptibility to acetone:water plant extracts between infective larvae (L3) of ten Haemonchus contortus isolates from different geographical origin. The L3 of 10 different isolates were exposed either to the acetone:water extract of a temperate plant (Onobrychis viciifolia) or a tropical plant (Acacia pennatula) and were evaluated with the larval exsheathment inhibition assay (LEIA). The L3 of each isolate were incubated with different concentrations of each extract (0, 25, 50, 100, 200, 400, 600, 800, 1000 and 1200μg/mL of phosphate buffered saline (PBS)). After incubation, the exsheathment process of L3 was induced using a solution with sodium hypochlorite (2%) and sodium chloride (16.5%). The proportion of exsheathed L3 was determined for each concentration at 0, 20, 40 and 60min. Effective concentrations 50% (EC50) and the corresponding 95% confidence intervals (95% CI) were calculated for every isolate with both extracts. Moreover, a resistance ratio (RR) was calculated for each extract to compare isolates, using the most susceptible isolate as the respective reference for each extract. To determine the role of polyphenols on the reported effect, a second set of incubations was made for each isolate and each extract, using the extracts at a concentration of 1200μg/mL PBS with or without polyvinylpolypyrrolidone (PVPP), a polyphenol blocking agent, and controls without extract. The ten different H. contortus isolates showed variation in susceptibility for each of the 2 extracts tested (P<0.05). The EC50 values for A. pennatula extract ranged from 36 to 501μg/mL (RR: 2.11–13.68). Meanwhile, the EC50 values for O. viciifolia extract ranged from 128 to 1003μg/mL (RR: 1.25–7.82). The use of PVPP revealed that polyphenols were responsible for the anthelmintic activity recorded for both extracts. However, tested H. contortus isolates suggested that susceptibility to one polyphenol-rich extract did not determine the susceptibility to the other polyphenol rich extract. The latter result indicated that the different H. contortus isolates varied in their susceptibility to the polyphenols present in each extract evaluated

Variabilidad en el contenido de polifenoles, actividad biológica y antihelmíntica de extractos metanol:agua de las hojas de Gymnopodium floribundum Rolfe

The effect of the harvest month and age of the leaves of Gymnopodium floribundum on the content of polyphenolic compounds (total phenols (TP), total tannins (TT) and condensed tannins (CT)) of methanol:water extracts was determined. In addition, the biological activity of polyphenols measured as the ability to precipitate protein (PP), inhibit egg hatching (EH), and larval exsheathment (LEI) of Haemonchus contortus was determined. G. floribundum leaves were harvested in 4 mo of the year: December, March, June and September. Twenty-four methanol:water extracts (70:30) were obtained, 12 produced from leaves of varied age (VA) and 12 from 90-d-old leaves (A90). All extracts caused similar PP regardless of age and harvest month. EH inhibition was only significant for December VA extract (EC50 = 374.4 μg/mL; P 1,500 μg/mL in December, June and September. Although all extracts inhibited larval exsheathment (LEI), the lowest EC50 was that of the VA leaf extract of June (EC50 = 80.4 μg/mL; P 1500 μg/ml en diciembre, junio y septiembre. Aunque todos los extractos inhibieron el desenvaine larval (IDL), la menor CE50 fue la del extracto de hojas EV de junio (CE50 = 80.4 μg/ml; P<0.05). La incubación de extractos con polivinilpolipirrolidona (PVPP) limitó la IDL (P<0.05), pero los polifenoles solo explicaron parte de esa actividad. En conclusión, el contenido de TC de los extractos de hojas de G. floribundum depende de su edad y mes de cosecha. Los polifenoles mostraron actividad de PP y se asociaron parcialmente con la IDL. Sin embargo, los polifenoles no explican la actividad contra huevos de H. contortus

A Review of Deep Learning Fundamentals – the XOR Neural Network Model

This paper explores the fundamentals of Deep Learning by searching a simple Neural Network model of the XOR function for the forward and backward signals flowing through this model. Our purpose is to reach a deeper understanding of some outstanding concepts of Deep Learning, which would enable us to get the significance of it while the Neural Network model of the XOR function is trained by the backpropagation algorithm. The chosen Neural Network model contains just one hidden layer with four neurons and an output layer with one neuron. Although this model is not a deep neural network, its hidden layer carries the enough concepts of Deep Learning. The sigmoid is used as the activation function in all neurons. A derivation of a simple version of the Stochastic Gradient Descent algorithm is presented, which is used to minimize the output error, and then by backpropagating it we come to the backpropagation algorithm. Numerical results are presented, which shows the convergence of the output error and that of a selected weight and their analysis summarize the understanding of the fundamental concepts of Deep Learning

Frequency of Trypanosoma cruzi Infection in Synanthropic and Wild Rodents Captured in a Rural Community in Southeast of Mexico

The protozoan parasite Trypanosoma cruzi is the causative agent of the Chagas disease, which is endemic in southeastern Mexico and is transmitted by the vector Triatoma dimidiata (triatomide). T. cruzi infect a great variety of domestic and wild mammals; rodents are considered one of the most important reservoirs of the parasite in the transmission cycles of T. cruzi. The objective of this study was to determine the frequency of T. cruzi infection and to determine the parasitic load in synanthropic and wild rodents from the rural community of southern Mexico. A total of 41 blood samples and 68 heart tissue samples were collected from various species of synanthropic (n= 48 in 2 species) and wild rodents (n= 35 in 5 species). DNA was extracted from samples to detect the presence of T. cruzi through quantitative PCR (qPCR). T. cruzi DNA was detected in the 9.75% of the blood samples of the synanthropic species (4/41) (14.28%) for Rattus rattus samples and 25% for Ototylomys phyllotis samples, with an average of parasitic load of 4.80 ± 1.17 parasites/μL. In the case of heart tissue samples, 10.29% were positive for T. cruzi (7/68) (8.7% for Rattus rattus, 40% for Peromyscus yucatanicus, and 42.8% for Ototylomys phyllotis) with an average parasite load of 3.15 ± 1.98 eq-parasites/mg. The active and chronic infection of T. cruzi in synanthropic or wild rodents of the rural community of southern Mexico evidences the natural infection in these reservoirs which contribute to maintaining the agent in the wild and domestic environments and can represent a risk of infection for the human population when the vector is present

In vitro Evaluation of the Nutraceutical Potential of Theobroma cacao pod Husk and Leaf Extracts for Small Ruminants

International audiencePurpose: Some agroindustrial by-products could be used as nutraceutical materials for small ruminants helping with their nutrition while controlling their gastrointestinal nematodes. This study evaluated the potential in vitro nutraceutical value of pod husks and leaves of three varieties of Theobroma cacao using two Haemonchus contortus isolates with different polyphenol susceptibility.Methods: Leaves and husks from three T. cacao varieties (AZT, CAL and CEY) were evaluated for their bromatological composition, in vitro dry matter digestibility and polyphenol content. Acetone:water extracts (70:30) of each plant variety were evaluated using the egg hatch and larval exsheathment inhibition tests, using two isolates (FESC and PARAISO) of H. contortus. Effective concentrations 50% (EC50) were determined for both tests. The role of polyphenols was confirmed using polyvinylpolypyrrolidone. L3 exposed to CAL leaf extract were submitted to transmission electron microscopy.Results: Both plant materials showed a good nutritional value to complement protein-rich diets for small ruminants. Extracts inhibited exsheathment of H. contortus L3 more effectively than the egg hatching, and the leaf extracts were more active than husk extracts in the L3 exsheathment inhibition. The FESC isolate was more sensitive to extracts. Polyphenols blocked exsheathment inhibition of leaf extracts. Structural damage was observed in the sheath and muscles of L3 exposed to CAL leaf extracts.Conclusion: The two T. cacao materials tested showed their potential to be used as ruminant feeds. Extracts affected H. contortus by blocking L3 exsheathment, particularly with the leaf extracts. The in vivo nutraceutical value should be confirmed in small ruminants

Patterns of oral anticoagulant use and outcomes in Asian patients with atrial fibrillation: a post-hoc analysis from the GLORIA-AF Registry

Background: Previous studies suggested potential ethnic differences in the management and outcomes of atrial fibrillation (AF). We aim to analyse oral anticoagulant (OAC) prescription, discontinuation, and risk of adverse outcomes in Asian patients with AF, using data from a global prospective cohort study. Methods: From the GLORIA-AF Registry Phase II-III (November 2011-December 2014 for Phase II, and January 2014-December 2016 for Phase III), we analysed patients according to their self-reported ethnicity (Asian vs. non-Asian), as well as according to Asian subgroups (Chinese, Japanese, Korean and other Asian). Logistic regression was used to analyse OAC prescription, while the risk of OAC discontinuation and adverse outcomes were analysed through Cox-regression model. Our primary outcome was the composite of all-cause death and major adverse cardiovascular events (MACE). The original studies were registered with ClinicalTrials.gov, NCT01468701, NCT01671007, and NCT01937377. Findings: 34,421 patients were included (70.0&nbsp;±&nbsp;10.5 years, 45.1% females, 6900 (20.0%) Asian: 3829 (55.5%) Chinese, 814 (11.8%) Japanese, 1964 (28.5%) Korean and 293 (4.2%) other Asian). Most of the Asian patients were recruited in Asia (n&nbsp;=&nbsp;6701, 97.1%), while non-Asian patients were mainly recruited in Europe (n&nbsp;=&nbsp;15,449, 56.1%) and North America (n&nbsp;=&nbsp;8378, 30.4%). Compared to non-Asian individuals, prescription of OAC and non-vitamin K antagonist oral anticoagulant (NOAC) was lower in Asian patients (Odds Ratio [OR] and 95% Confidence Intervals (CI): 0.23 [0.22-0.25] and 0.66 [0.61-0.71], respectively), but higher in the Japanese subgroup. Asian ethnicity was also associated with higher risk of OAC discontinuation (Hazard Ratio [HR] and [95% CI]: 1.79 [1.67-1.92]), and lower risk of the primary composite outcome (HR [95% CI]: 0.86 [0.76-0.96]). Among the exploratory secondary outcomes, Asian ethnicity was associated with higher risks of thromboembolism and intracranial haemorrhage, and lower risk of major bleeding. Interpretation: Our results showed that Asian patients with AF showed suboptimal thromboembolic risk management and a specific risk profile of adverse outcomes; these differences may also reflect differences in country-specific factors. Ensuring integrated and appropriate treatment of these patients is crucial to improve their prognosis. Funding: The GLORIA-AF Registry was funded by Boehringer Ingelheim GmbH

Correction to: Comparative effectiveness and safety of non-vitamin K antagonists for atrial fibrillation in clinical practice: GLORIA-AF Registry

International audienceIn this article, the name of the GLORIA-AF investigator Anastasios Kollias was given incorrectly as Athanasios Kollias in the Acknowledgements. The original article has been corrected