Biology subjects

Villena, I.

Publications and source records attributed to Villena, I..

3 recordsLinked to original sources

bioRxiv2025

Effects of host sex, age and behaviour on co-infection patterns in a wild ungulate

Recent zoonotic disease emergences reveal the importance of studying wildlife parasite communities. As wild hosts frequently harbour diverse parasite species, understanding the drivers of multiple infection patterns in free-ranging hosts is critical for elucidating the ecological and epidemiological dynamics of parasite communities. In this study, we analysed co-infection patterns in European roe deer (Capreolus capreolus) inhabiting a fragmented rural landscape in southwestern France. Using data from 130 GPS-tracked roe deer, we examined the influence of proximity to livestock, host activity levels, age, sex, and between-parasite interactions on the presence of 11 parasitic taxa. Hierarchical modelling of species communities (HMSC) revealed that proximity to livestock significantly increased the likelihood of infection with orofecally transmitted parasites (Toxoplasma gondii, gastrointestinal parasites). Sex and age were other key predictors, with males and juveniles exhibiting a higher frequency of parasite presence, likely influenced by hormonal and immune system differences. Activity levels showed distinct age-related effects, with higher activity levels being positively associated with increased parasite prevalence in yearlings, but not in adults. In contrast, parasite association patterns within individual hosts were weak, suggesting minimal interactions between parasite species. Our findings highlight the interplay between exposure and susceptibility in shaping co-infection patterns and underscore the value of hierarchical modelling approaches in multi-parasite systems. Key FindingsO_LIParasite communities, studied in 130 GPS monitored roe deer, revealed frequent co-infection. C_LIO_LIProximity to livestock increased the risk of infection by parasite taxa shared with domestic animals. C_LIO_LIFor several parasitic taxa, males and younger roe deer had a higher probability of infection. C_LIO_LIThe effect of host activity on parasite infection was dependent on roe deer age. C_LIO_LIOnly slight between-parasite interactions were detected within individual hosts. C_LI

ecology↗

bioRxiv2024

Anti-Toxoplasma gondii screening of eight species and bio-guided identification of metabolites of Elaeis guineensis leaves, a preliminary study

The apicomplexan parasite Toxoplasma gondii causes toxoplasmosis, a ubiquitous and cosmopolitan parasitosis, generally asymptomatic and potentially dangerous for the fetus and highly immunocompromised patients. Pyrimethamine and sulfadiazine, supplemented with folic acid, are the drugs of choice to treating the disease, but they produce severe side effects and treatments fail due to drug resistance. New anti-Toxoplasma compounds are needed, and natural compounds can be a good source for obtaining them. The antiparasitic activity of 40 polar and non-polar extracts of eight antiparasitic medicinal plants used in Cote dIvoire, and selected based on ethnopharmacological survey, were evaluated in vitro against T. gondii. Among them, the hydromethanolic extract of the Elaeis guineensis leaves exhibited the best parasite growth inhibition (94% {+/-} 0.07) at 25 g/mL without being cytotoxic at the same dose. The fractionation of this extract did not allow the recovery of antitoxoplasmic activity in its individualized fractions. The 13C-NMR based dereplication of the produced fractions and the purification of one of them highlighted the presence of saccharides, terpenes, flavonoids, cardanols and aliphatic acids. The obtained clusters of 13C chemical shifts were assigned to their corresponding molecular structures with the help of open online databases, resulting in nine unambiguously identified compounds, whereas the purification of one of these fractions led to the identification of palmitic acid (10), palmitic acid methyl ester (11), 3-[12(E)-pentadecenyl]phenol (12), 3-[14(E)-heptadecenyl]phenol (13), ursolic acid (14) and stigmasta-4,24(28)-dien-3-one (15). A synergistic effect between these metabolites is thought to be responsible for the anti-Toxoplasma activity. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/600452v1_ufig1.gif" ALT="Figure 1"> View larger version (57K): org.highwire.dtl.DTLVardef@17a8885org.highwire.dtl.DTLVardef@198e909org.highwire.dtl.DTLVardef@1eb643borg.highwire.dtl.DTLVardef@1018053_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGRAPHICAL ABSTRACTC_FLOATNO C_FIG HighlightsO_LIAntiparasitic activity of 40 polar and non-polar extracts of eight plants were investigated C_LIO_LIThe hydromethanolic extract of the E. guineensis leaves exhibited 94% parasite growth inhibition C_LIO_LIThe fractionation of this extract did not allow the recovery of antitoxoplasmic activity C_LIO_LINine compounds were identified by 13C-NMR based dereplication C_LIO_LISix compounds were purified from the cytotoxic fraction C_LI

pharmacology and toxicology↗

bioRxiv2024

Detection of Echinococcus spp. and other taeniid species in lettuces and berries: two international multicenter studies from the MEmE project

Cystic and alveolar echinococcosis are severe zoonotic diseases characterized by long asymptomatic periods lasting months or years. Viable Echinococcus eggs released into the environment through the feces of canids can infect humans through accidental ingestion via hand-to-mouth contact or consumption of contaminated food or water. Both Echinococcus multilocularis and Echinococcus granulosus sensu lato are considered as foodborne parasites. However, when considering possible pathways of human infection, it appears that food and water-borne related variables do not significantly increase the risk of infection. Providing evidence-based data for the presence of DNA and, potentially, eggs in fresh produce is crucial in understanding foodborne transmission of Echinococcus spp. to humans. Two multicenter and multicountry studies were conducted within the One Health EJP framework to estimate the proportion of lettuces and berries contaminated by E. multilocularis, E. granulosus s.l., and other taeniid DNAs from 12 European countries, Tunisia and Pakistan. A total of 1,117 lettuces, 300 strawberries and 130 blueberries samples were collected and analyzed by washing, sequential sieving and real-time PCRs. Echinococcus multilocularis DNA was detected in 1.2% (7/570) of samples tested from the seven European endemic areas and in 2% (2/100) from Pakistan. In the five European endemic countries for E. granulosus s.l., E. granulosus sensu stricto DNA was identified in 1.3% of lettuces (9/695). The proportion of lettuces contaminated by E. granulosus sensu stricto DNA was 12% (9/75) in Tunisia and 4% (4/100) in Pakistan. Regarding berries, E. multilocularis DNA was detected in 5.4% of strawberries (n=11/202), 7.3% of blueberries (6/82) from the seven European endemic countries and 56% of blueberries (14/25) from Pakistan. High contamination rates of E. granulosus s.s were found outside of Europe, with 12.0% in blueberries (3/25) from Pakistan and 81.3%. DNA in strawberries (13/16) from Tunisia. The total contamination rate of all taeniid species DNA in lettuces (5.3%; 59/1,117) and berries (12.1%; 58/480) suggests that the transfer of taeniid eggs from carnivore feces to food is not uncommon. Although we assume that eggs are the source of the DNA detected in this study, the viability of such eggs is unknown. The detection of Echinococcus species in lettuces and berries suggests a potential risk of foodborne human infection. The relative contribution of this risk remains to be estimated. Further studies on food and environmental contamination are necessary to cover different epidemiological contexts and social habits, leading to a better understanding of human infections by Echinococcus eggs.

microbiology↗