scholarly journals Parasitic nematodes simultaneously suppress and benefit from coccidian coinfection in their natural mouse host

Parasitology ◽  
2019 ◽  
Vol 146 (8) ◽  
pp. 1096-1106 ◽  
Author(s):  
Melanie Clerc ◽  
Andy Fenton ◽  
Simon A. Babayan ◽  
Amy B. Pedersen

AbstractWithin-host interactions among coinfecting parasites are common and have important consequences for host health and disease dynamics. However, these within-host interactions have traditionally been studied in laboratory mouse models, which often exclude important variation and use unnatural host–parasite combinations. Conversely, the few wild studies of within-host interactions often lack knowledge of parasite exposure and infection history. Here we exposed laboratory-reared wood mice (Apodemus sylvaticus) that were derived from wild-caught animals to two naturally-occurring parasites (nematode: Heligmosomoides polygyrus, coccidia: Eimeria hungaryensis) to investigate the impact of coinfection on parasite infection dynamics, and to determine if the host immune response mediates this interaction. Coinfection led to delayed worm expulsion and prolonged egg shedding in H. polygyrus infections and lower peak E. hungaryensis oocyst burdens. By comparing antibody levels between wild and colony-housed mice, we also found that wild mice had elevated H. polygyrus-IgG1 titres even if currently uninfected with H. polygyrus. Using this unique wild-laboratory system, we demonstrate, for the first time, clear evidence for a reciprocal interaction between these intestinal parasites, and that there is a great discrepancy between antibody levels measured in the wild vs those measured under controlled laboratory conditions in relation to parasite infection and coinfection.

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1300
Author(s):  
Xavier Blasco ◽  
Xavier Manteca ◽  
Manel López-Béjar ◽  
Anaïs Carbajal ◽  
Joaquim Castellà ◽  
...  

Housing conditions were assessed in different unowned multi-cat management models in order to evaluate their impact on the occurrence of intestinal parasites and fecal cortisol metabolite (FCM) levels. Fresh stool fecal samples were collected from rescue shelters, catteries and feline colonies for coprological analyses in order to detect intestinal parasite patency and fecal cortisol metabolites. A questionnaire provided information about the facilities, management and housing conditions of cats, including information about dog exposure, enclosure size, environment enrichment and changes to group composition. Overall, intestinal parasite infection was detected in 58.2% of fecal samples collected. The occurrence of intestinal parasites detected in free-roaming cats was 82.2%, mainly due to helminth infection. The parasite infection rate was 57.3% in rescue shelters and 34.6% in catteries. In confined cats, protozoa infection was more likely detected in rescue shelters than in catteries (RR = 2.02 (1.30–3.14), p = 0.0012). Although the FCM values were very variable between cats, the enclosure size and parasite infection were correlated with the average FCM. A small enclosure size was correlated with high fecal cortisol metabolites (p = 0.016). Protozoa-positive samples showed higher FCM levels than negative samples (p = 0.0150). High dog exposure was statistically associated with protozoa infection (p = 0.0006). The results indicated that improving housing, especially in terms of floor space and avoiding dog exposure, reduces stress and can thus be applied to make control strategies in multi-unowned-cat environments more efficient, especially when cats are confined.


2003 ◽  
Vol 33 (3) ◽  
pp. 139-143 ◽  
Author(s):  
G M Monawar Hosain ◽  
Subas Saha ◽  
Afroza Begum

This study was carried out in 1999–2000 in the northern part of Bangladesh to determine the impact of sanitary latrine use and of health education on intestinal parasites in school-aged children. The children were between 5 and 13 years of age and stool samples revealed that more than half (53%) of the study sample was still infected with one or more intestinal parasites even after 4 years of intervention. Ascariasis was found to have the highest prevalence rate (36.2%) and hookworm the lowest (10.7%). Intestinal parasite infection was significantly lower ( P<0.05) among those who used a sanitary latrine and received health education. This result is consistent with observations that the effect of sanitation and health education is slow to develop. Concerted primary healthcare activities with community development efforts should be undertaken to improve the overall living condition of the people of this area to control this problem.


2018 ◽  
Vol 86 (5) ◽  
Author(s):  
Mancheong Ma ◽  
Daniel A. Powell ◽  
Nathan J. Weyand ◽  
Katherine A. Rhodes ◽  
María A. Rendón ◽  
...  

ABSTRACTCommensals are important for the proper functioning of multicellular organisms. How a commensal establishes persistent colonization of its host is little understood. Studies of this aspect of microbe-host interactions are impeded by the absence of an animal model. We have developed a natural small animal model for identifying host and commensal determinants of colonization and of the elusive process of persistence. Our system couples a commensal bacterium of wild mice,Neisseria musculi, with the laboratory mouse. The pairing of a mouse commensal with its natural host circumvents issues of host restriction. Studies are performed in the absence of antibiotics, hormones, invasive procedures, or genetic manipulation of the host. A single dose ofN. musculi, administered orally, leads to long-term colonization of the oral cavity and gut. All mice are healthy. Susceptibility to colonization is determined by host genetics and innate immunity. ForN. musculi, colonization requires the type IV pilus. Reagents and powerful tools are readily available for manipulating the laboratory mouse, allowing easy dissection of host determinants controlling colonization resistance.N. musculiis genetically related to human-dwelling commensal and pathogenicNeisseriaand encodes host interaction factors and vaccine antigens of pathogenicNeisseria. Our system provides a natural approach for studyingNeisseria-host interactions and is potentially useful for vaccine efficacy studies.


2007 ◽  
Vol 47 (5) ◽  
pp. 620 ◽  
Author(s):  
B. L. Blair ◽  
G. R. Stirling

Damage to sugarcane caused by root-knot nematode (Meloidogyne spp.) is well documented in infertile coarse-textured soils, but crop losses have never been assessed in the fine-textured soils on which more than 95% of Australia’s sugarcane is grown. The impact of nematodes in these more fertile soils was assessed by repeatedly applying nematicides (aldicarb and fenamiphos) to plant and ratoon crops in 16 fields, and measuring their effects on nematode populations, sugarcane growth and yield. In untreated plant crops, mid-season population densities of lesion nematode (Pratylenchus zeae), root-knot nematode (M. javanica), stunt nematode (Tylenchorhynchus annulatus), spiral nematode (Helicotylenchus dihystera) and stubby-root nematode (Paratrichodorus minor) averaged 1065, 214, 535, 217 and 103 nematodes/200 mL soil, respectively. Lower mean nematode population densities were recorded in the first ratoon, particularly for root-knot nematode. Nematicides reduced populations of lesion nematode by 66–99% in both plant and ratoon crops, but control of root-knot nematode was inconsistent, particularly in ratoons. Nematicide treatment had a greater impact on shoot and stalk length than on shoot and stalk number. The entire community of pest nematodes appeared to be contributing to lost productivity, but stalk length and final yield responses correlated most consistently with the number of lesion nematodes controlled. Fine roots in nematicide-treated plots were healthier and more numerous than in untreated plots, and this was indicative of the reduced impact of lesion nematode. Yield responses averaged 15.3% in plant crops and 11.6% in ratoons, indicating that nematodes are subtle but significant pests of sugarcane in fine-textured soils. On the basis of these results, plant-parasitic nematodes are conservatively estimated to cost the Australian sugar industry about AU$82 million/annum.


2016 ◽  
Vol 4 (4) ◽  
pp. 28
Author(s):  
Sabri Braha ◽  
Petrit Rama

The purpose of this research is to determine the impact of the turf-only substrate and turf–perlite in the ratio 2:1 and of growth regulators in the quality of adventive roots ( the number and length) of well lignified one-year old branches without fruit buds in the Bluecrop cultivar (Vaccinium corymbosum L.) taken at the end of the latent period before budding at the February 15 th during the -2015 growing season. In order to support the increase of the number of roots and their length the hardwood cuttings are treated with different IBA and NAA concentrations (1500, 3000, 4500 ppm), while a part of cuttings were untreated control. The number and the length of roots have increased in relation to the increase of concentration from 1500 to 3000 ppm followed by a decline of these values in concentrations over 3000 ppm. Respectively, the number of roots (8) and the higher values of root length (4.6 cm) are achieved in the turf–perlite substrate, IBA 3000 ppm (compared to the turf-only substrate). The presence of perlite helps the aeration of the substrate and supports biochemical and physiological processes which lead to the inducing of adventive roots. Regarding the number and length of roots an important variation for (p<0.05) was observed between different concentrations of IBA and NAA. In general the effect of IBA was a lot better than the effect of NAA.


Genes ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 41
Author(s):  
Ernesto Picardi ◽  
Luigi Mansi ◽  
Graziano Pesole

ADAR1-mediated deamination of adenosines in long double-stranded RNAs plays an important role in modulating the innate immune response. However, recent investigations based on metatranscriptomic samples of COVID-19 patients and SARS-COV-2-infected Vero cells have recovered contrasting findings. Using RNAseq data from time course experiments of infected human cell lines and transcriptome data from Vero cells and clinical samples, we prove that A-to-G changes observed in SARS-COV-2 genomes represent genuine RNA editing events, likely mediated by ADAR1. While the A-to-I editing rate is generally low, changes are distributed along the entire viral genome, are overrepresented in exonic regions, and are (in the majority of cases) nonsynonymous. The impact of RNA editing on virus–host interactions could be relevant to identify potential targets for therapeutic interventions.


2004 ◽  
Vol 4 (4) ◽  
pp. 13-18 ◽  
Author(s):  
Jerrold J. Scharninghausen ◽  
Michael Faulde ◽  
Semra Cavaljuga

Viral studies have historically approached their phylogenetic analysis without consideration of the impact of the role the host plays in evolution. Our study examines host/viral interactions through analysis of the phylogenetic relationship between hantavirus genetic sequences and host cytochrome B sequences. Phylogenetic analysis of known Hantavirus genetic sequences were performed using PAUP 3.1.1 (vers. 4.0.0d64). Only sequences available through GENBANK were analyzed. Phylogenetic analysis of hantavirus sequences revealed distinct patterns based upon geographic area. These patterns coincided with the known ranges of reservoir hosts. Multiple hosts for individual viruses and multiple viruses in a single host species for hantaviruses have been described. This may be due to accidental exposure, host-switching, co-speciation, or broad co-accommodation. Since the host is the actual environment that the virus survives in, changes in the host over time could potentially directly influence changes in the virus. Multiple viruses and hosts collide in Southeastern Europe increasing the prospect of finding distinct viral/host relationships. Rodent Cytochrome B is very well conserved and can be used to tract host lineage. By tracking the relationship of infected hosts, we theorize that patterns in host DNA will emerge that will mirror patterns in viral sequences. This analysis of the host DNA could provide an understanding into the causes of variation in hantaviral sequences, pathogenicity, transmissibility, infectivity, viral range and expand our knowledge of viral/host interactions. Surveillance for viruses in the field should include analysis of the host DNA in combination with the viral analysis.


2020 ◽  
Vol 11 (2) ◽  
pp. 344-348
Author(s):  
O. O. Boyko ◽  
V. V. Brygadyrenko

The article describes a laboratory study of nematocidal properties of flavourings with antibacterial effect against Ascaris suum (Goeze, 1782) and Trichuris suis Schrank, 1788. In the experiments, eight concentrations of food additives with antibacterial properties were used: cinnamaldehyde, benzoic acid, formic acid, linalool, citral, β-ionone. Minimum LC50 value for eggs of A. suum was observed while using cinnamaldehyde and benzoic acid – 1.62 ± 0.37% and 1.69 ± 0.14%, and for eggs of T. suis – 0.57 ± 0.03% and 1.80 ± 0.11% respectively. The lowest influence on the development of eggs of nematodes of pigs’ A. suum and T. suis was exerted by formic acid, linalool, citral and β-ionone. In eggs of A. suum and T. suis, larvae formed in 21 and 50 days even during exposure to 3% emulsions of these substances. The strongest negative impact on the eggs of parasitic nematodes was displayed by cinnamaldehyde flavouring. Further study on nematocidal properties of flavourings, as well as their mixtures, would contribute to the development of preparations which would have a strong effect on eggs and larvae of nematodes of animals and humans.


2021 ◽  
Author(s):  
Massimo La Raja ◽  
Monia Pacenti ◽  
Ileana Grimaldi ◽  
Caterina Boldrin ◽  
Margherita Cattai ◽  
...  

From April 2020 through May 2021 in Padova Province 3395 COVID-19 recovered patients were recruited as potential convalescent plasma donors and tested for SARS-CoV-2 antibodies. Since January 2021 COVID-19 vaccination campaign began in Italy, the impact of vaccination on antibody levels and suspect vaccine breakthrough infections in these subjects were investigated. Post-vaccination anti-Sars-Cov-2 antibody level in 54 previously infected subjects had an exponential increase compared to pre-vaccination level regardless of the number of vaccine doses. However after 100 days from vaccination SARS-CoV-2 antibody level tends to decline. Post-vaccination primary infections were detected in 15 cases, with 3 possible breakthrough infections after a full vaccination course. In these cases, antibody response after infection was present but weaker than the one of subjects vaccinated after natural infection. A trend toward stronger antibody response was observed with increasing distance between natural infection and vaccination. Additionally, 2 cases of asymptomatic reinfections are also discussed.


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