International journal for parasitology最新文献

{"title":"Bat microfilariae in the cityscape: a transmission tale between bats, mites, and bat flies.","authors":"Román Espinal-Palomino, Ana Celia Montes de Oca-Aguilar, Martha Pilar Ibarra-López, Víctor M Vidal-Martínez, Carlos N Ibarra-Cerdeña","doi":"10.1016/j.ijpara.2024.11.001","DOIUrl":"10.1016/j.ijpara.2024.11.001","url":null,"abstract":"<p><p>Litomosoides includes filarial nematodes capable of infecting various vertebrate species. While Litomosoides has been extensively studied in rodents, research on its association with bats remains limited. The transmission dynamics of this parasite are complex, involving moving between different invertebrate hosts before reaching the final host. Most investigations concerning microfilariae have concentrated on their morphological characteristics, with scant attention paid to ecological aspects, particularly in human-altered landscapes. This study represents the first known documentation of Litomosoides in bats within an urban environment. It investigates their response to urbanization in their interaction with the synanthropic bat Artibeus jamaicensis and its ectoparasites. The objective was to explore the influence of urban landscapes on Litomosoides prevalence in synanthropic hosts. Blood samples were collected along urban-rural gradients, and parasite presence was confirmed through direct observation in blood smears and PCR. Phylogenetic analysis based on the mitochondrial cytochrome c oxidase subunit 1 gene (COX1), which exhibited robust support values, indicates that the microfilaria found in A. jamaicensis is closely related to Litomosoides chandleri. However, it also suggests the possibility of an unidentified, and therefore potentially new, species within the genus Litomosoides. Additionally, Litomosoides DNA was detected in Periglischrus iheringi (Acari: Spinturnicidae) and in the bat fly Trichobius intermedius collected from the bat. The parasite sequences obtained from these three interacting species exhibited a genetic distance as low as 0.002. The highest prevalences were recorded in forested areas (28.6%) compared with urban areas (21.2%). However, within the urban landscape, prevalence varied from 3.8% to 21.2%, being highest in densely built-up areas. Analysis of the urban landscape suggested that the prevalence of Litomosoides in A. jamaicensis is the result of a multifactorial and synergistic process involving ectoparasite load, host abundance, and the extent of impervious surfaces (NDBI).</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mitogenomic analysis of the position of the Azygiidae and constituent genera, with a new species of Azygia.","authors":"Danimar López-Hernández, Florian B Reyda, Wenxiang Li, Hudson A Pinto, Sean A Locke","doi":"10.1016/j.ijpara.2024.11.002","DOIUrl":"10.1016/j.ijpara.2024.11.002","url":null,"abstract":"<p><p>The Azygiidae Looss, 1899 is a family of digeneans with a Holarctic distribution in which members of some genera mature in marine elasmobranchs while others occur only in freshwater teleosts. Some have questioned whether the marine genus Otodistomum Stafford, 1904 indeed belongs to the same family as the freshwater azygiid genera, namely Azygia Looss, 1899, Proterometra Horsfall, 1933, and Leuceruthrus Marshall and Gilbert, 1905. We present phylogenetic analyses based on mitochondrial genomes, rDNA operons, and partial cytochrome c oxidase I (Cox1) sequences from North American and Asian species that support the monophyly of Azygiidae, and placement of Azygioidea in the suborder Hemiurata, in contrast to recently published mitochondrial genome phylogenies. All phylogenies indicate that Azygia includes Leuceruthrus, which we therefore propose to be a junior synonym, together with suppression of the Leuceruthrinae. The status of Proterometra was equivocal, with support in some but not all analyses of 28S, but not in other markers. We describe a new species of Azygia from northeastern North America. Our results confirm the morphological variability of adults in Azygia, with worm size positively correlated with host size in Azygia angusticauda. Phylogenies suggest a marine origin for the Azygiidae, and a Palearctic origin for freshwater azygiids, with a single trans-Atlantic radiation to the Nearctic.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dense aquatic vegetation can reduce parasite transmission to amphibians.","authors":"Marin Milotic, Dino Milotic, Janet Koprivnikar","doi":"10.1016/j.ijpara.2024.11.003","DOIUrl":"https://doi.org/10.1016/j.ijpara.2024.11.003","url":null,"abstract":"<p><p>Submerged aquatic vegetation (macrophytes) can provide prey with refuges from predators and may perform a similar role for interactions with other natural enemies such as parasites. This could occur by interfering with the ability of free-swimming infectious parasite stages to locate or move towards hosts, reducing infections. Alternatively, infections may increase if macrophytes reduce host anti-parasite behaviours such as detection or evasion. Both scenarios could be affected by macrophyte density and structural complexity. Here we investigated whether experimental infection of tadpoles (Rana sylvatica and Rana pipiens) by parasitic flatworms (the trematodes Ribeiroia ondatrae and Echinostoma spp. was affected by the presence of artificial vegetation with varying density and complexity (simple versus branching), as well as tadpole activity under these conditions. Macrophyte presence significantly reduced tadpole infection loads only in the highest density treatment, but there was no effect of structural complexity. Related to this, tadpoles spent significantly more time near aquatic vegetation when it was dense but showed no preference for either structural type. Our results indicate that aquatic vegetation can reduce parasite transmission in certain scenarios, with further studies needed to explore how structural complexity in natural systems can affect host-parasite interactions, considering the massive physical alterations possible through eutrophication and the introduction of invasive plant species.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A footworm in the door: revising Onchocerca phylogeny with previously unknown cryptic species in wild North American ungulates.","authors":"Matthew R Kulpa, Emilie Lefoulon, Kimberlee B Beckmen, Samantha E Allen, Jennifer Malmberg, John A Crouse, Daniel P Thompson, Bridgett M Benedict, Dayna A Goldsmith, Sara McCarthy, Lee C Jones, Michael J Yabsley, James M Crum, Susan J Kutz, Guilherme G Verocai","doi":"10.1016/j.ijpara.2024.10.006","DOIUrl":"https://doi.org/10.1016/j.ijpara.2024.10.006","url":null,"abstract":"<p><p>Onchocerca is an important genus of vector-borne filarial nematodes that infect both humans and animals worldwide. Many Onchocerca spp., most of medical and veterinary health relevance, are the focus of a variety of diagnostic and molecular research. However, despite the importance of these parasites, there is growing evidence of previously unexplored genetic diversity of these nematodes, particularly among wild ungulate hosts in North America. These understudied parasites prevent us from comprehending the evolutionary history of the genus Onchocerca, monitoring potential One Health threats, and improving our filarioid diagnostic capabilities. In order to fill these knowledge gaps, we identified five uncharacterized Onchocerca lineages and compared them with other well-known filarioid species using single and concatenated gene regions (i.e., nd5, cox1, 12S, 18S, 28S, hsp70, MyoHC, rbp1). Phylogenetic analyses revealed that the novel Onchocerca lineages of wild North American ungulates segregate into two clades. One clade comprised Onchocerca lineages II, IV, and V and other species found mainly in domestic animals and humans, and the second comprised Onchocerca lineages I and III and other species from a variety of hosts including cervids, bovids, and equids. The formation of two clearly separate clades supports the idea of at least two independent expansion events of ancestral Onchocerca spp. into the North American continent via the Bering land bridge. Cophylogenetic analysis shows evidence of ancestral Onchocerca spp. of Bovidae host-switching to wild Cervidae and giving rise to the novel Onchocerca spp. Lastly, pairwise analysis confirms informative molecular markers of diagnostic relevance in both mitochondrial and nuclear gene regions of filarioid nematodes. The overall information provides greater context to the genus Onchocerca and emphasizes the need to discover, characterize, and monitor neglected parasites, especially those of wildlife origin.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The microRNAome of Strongylus vulgaris larvae and their excretory/secretory products with identification of parasite-derived microRNAs in horse arterial tissue.","authors":"Katrine Toft, Marie Louise Honoré, Nichol E Ripley, Martin K Nielsen, Bastian Fromm, Maibritt Mardahl, Lise N Nielsen, Peter Nejsum, Stig Milan Thamsborg, Susanna Cirera, Tina Holberg Pihl","doi":"10.1016/j.ijpara.2024.10.005","DOIUrl":"10.1016/j.ijpara.2024.10.005","url":null,"abstract":"<p><p>The equine bloodworm, Strongylus vulgaris, is a highly pathogenic parasite causing potentially fatal vascular and intestinal damage. Parasites express and release microRNAs (miRNAs) for internal regulation and to modulate host immunity. The complete set of miRNAs expressed by S. vulgaris (the S. vulgaris miRNAome) remains unannotated and the aim of this study was to annotate the miRNAome of L4 and L5 stages of S. vulgaris, and to examine differences in miRNA abundance between larval stages and sexes. Furthermore, we aimed to determine if miRNAs were detectable in excretory/secretory products (ESPs) from larvae and in arterial tissue from their predilection site, the cranial mesenteric artery (CMA). Larvae were collected from naturally infected foals, and categorized by sex and stage. A subset of larvae was snap-frozen, while those remaining were incubated and the (ESPs) collected. Arterial tissue samples were collected from the CMA. Small RNA sequencing, followed by a custom bioinformatic pipeline, was used for annotation. We identified 142 S. vulgaris miRNAs in larvae and 136 in ESPs. Significant differences in miRNA abundance were observed between larvae and ESPs, and between L5 females (L5Fs) and L5 males (L5Ms), L4s and L5Fs, and L4s and L5Ms. No differences were found between L4s and L5s overall. In ESPs, several miRNAs were differentially abundant across all groups. Validation through quantitative real-time PCR (qPCR) detected selected miRNAs and their differential abundance in larvae and ESPs. One parasite-derived miRNA was detected in some of the horse arterial tissue samples but at very low levels. This study provided the first annotation of the S. vulgaris miRNAome. Most of the annotated larval miRNAs were also detectable in ESPs, and differences in miRNA abundance between sexes were found for larvae, and between sexes and stages for ESPs. Parasite-derived miRNAs were, however, not consistently detectable in the surrounding host arterial tissue.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic and metagenomic analyses of the domestic mite Tyrophagus putrescentiae identify it as a widespread environmental contaminant and a host of a basal, mite-specific Wolbachia lineage (supergroup Q)","authors":"Pavel B. Klimov ,&nbsp;Jan Hubert ,&nbsp;Tomas Erban ,&nbsp;M. Alejandra Perotti ,&nbsp;Henk R. Braig ,&nbsp;Alex Flynt ,&nbsp;Qixin He ,&nbsp;Yubao Cui","doi":"10.1016/j.ijpara.2024.07.001","DOIUrl":"10.1016/j.ijpara.2024.07.001","url":null,"abstract":"<div><div><em>Tyrophagus putrescentiae</em> (mould mite) is a global, microscopic trophic generalist that commonly occurs in various human-created habitats, causing allergies and damaging stored food. Its ubiquity and extraordinary ability to penetrate research samples or cultures through air currents or by active walking through tights spaces (such as treads of screw caps) may lead to sample contamination and introduction of its DNA to research materials in the laboratory. This prompts a thorough investigation into potential sequence contamination in public genomic databases. The trophic success of <em>T. putrescentiae</em> is primarily attributed to the symbiotic bacteria housed in specialized internal mite structures, facilitating adaptation to varied nutritional niches. However, recent work suggests that horizontal transfer of bacterial/fungal genes related to nutritional functionality may also contribute to the mite’s trophic versatility. This aspect requires independent confirmation. Additionally, <em>T. putrescentiae</em> harbors an uncharacterized and genetically divergent bacterium, <em>Wolbachia</em>, displaying blocking and microbiome-modifying effects. The phylogenomic position and supergroup assignment of this bacterium are unknown. Here, we sequenced and assembled the <em>T. putrescentiae</em> genome, analyzed its microbiome, and performed detailed phylogenomic analyses of the mite-specific <em>Wolbachia</em>. We show that <em>T. putrescentiae</em> DNA is a substantial source of contamination of research samples. Its DNA may inadvertently be co-extracted with the DNA of the target organism, eventually leading to sequence contamination in public databases. We identified a diversity of bacterial species associated with <em>T. putrescentiae</em>, including those capable of rapidly developing antibiotic resistance, such as <em>Escherichia coli</em>. Despite the presence of diverse bacterial communities in <em>T. putrescentiae</em>, we did not detect any recent horizontal gene transfers in this mite species and/or in astigmatid (domestic) mites in general. Our phylogenomic analysis of <em>Wolbachia</em> recovered a basal, mite-specific lineage (supergroup Q) represented by two <em>Wolbachia</em> spp. from the mould mite and a gall-inducing plant mite. Fluorescence in situ hybridization confirmed the presence of <em>Wolbachia</em> inside the mould mite<em>.</em> The discovery of an early derivative <em>Wolbachia</em> lineage (supergroup Q) in two phylogenetically unrelated and ecologically dissimilar mites suggests that this endosymbiotic bacterial lineage formed a long-term association with mites. This finding provides a unique insight into the early evolution and host associations of <em>Wolbachia</em>. Further discoveries of <em>Wolbachia</em> diversity in acariform mites are anticipated.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 13","pages":"Pages 661-674"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141590232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chromosome-contiguous genome for the Haecon-5 strain of Haemonchus contortus reveals marked genetic variability and enables the discovery of essential gene candidates","authors":"Yuanting Zheng ,&nbsp;Neil D. Young ,&nbsp;Tulio L. Campos ,&nbsp;Pasi K. Korhonen ,&nbsp;Tao Wang ,&nbsp;Sunita B. Sumanam ,&nbsp;Aya C. Taki ,&nbsp;Joseph J. Byrne ,&nbsp;Bill C.H. Chang ,&nbsp;Jiangning Song ,&nbsp;Robin B. Gasser","doi":"10.1016/j.ijpara.2024.08.003","DOIUrl":"10.1016/j.ijpara.2024.08.003","url":null,"abstract":"<div><div>Millions of livestock animals worldwide are infected with the haematophagous barber’s pole worm, <em>Haemonchus contortus</em>, the aetiological agent of haemonchosis. Despite the major significance of this parasite worldwide and its widespread resistance to current treatments, the lack of a high-quality genome for the well-defined strain of this parasite from Australia, called Haecon-5, has constrained research in a number of areas including host-parasite interactions, drug discovery and population genetics. To enable research in these areas, we report here a chromosome-contiguous genome (∼280 Mb) for Haecon-5 with high-quality models for 19,234 protein-coding genes. Comparative genomic analyses show significant genomic similarity (synteny) with a UK strain of <em>H. contortus</em>, called MHco3(ISE).N1 (abbreviated as “ISE”), but we also discover marked differences in genomic structure/gene arrangements, distribution of nucleotide variability (single nucleotide polymorphisms (SNPs) and indels) and orthology between Haecon-5 and ISE. We used the genome and extensive transcriptomic resources for Haecon-5 to predict a subset of essential single-copy genes employing a “cross-species” machine learning (ML) approach using a range of features from nucleotide/protein sequences, protein orthology, subcellular localisation, single-cell RNA-seq and/or histone methylation data available for the model organisms <em>Caenorhabditis elegans</em> and <em>Drosophila melanogaster</em>. From a set of 1,464 conserved single copy genes, transcribed in key life-cycle stages of <em>H. contortus</em>, we identified 232 genes whose homologs have critical functions in <em>C. elegans</em> and/or <em>D. melanogaster</em>, and prioritised 10 of them for further characterisation; nine of the 10 genes likely play roles in neurophysiological processes, germline, hypodermis and/or respiration, and one is an unknown (orphan) gene for which no detailed functional information exists. Future studies of these genes/gene products are warranted to elucidate their roles in parasite biology, host-parasite interplay and/or disease. Clearly, the present Haecon-5 reference genome and associated resources now underpin a broad range of fundamental investigations of <em>H. contortus</em> and could assist in accelerating the discovery of novel intervention targets and drug candidates to combat haemonchosis.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 13","pages":"Pages 705-715"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142017329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micro RNA profiles of host extracellular vesicles are modulated by Ascaris suum infection but parasite extracellular vesicle miRNAs are systemically undetectable using in-depth miRNA sequencing","authors":"Bradley Whitehead ,&nbsp;Litten Sørensen Rossen ,&nbsp;Mads Zippor ,&nbsp;Anders T. Boysen ,&nbsp;Vineesh Indira Chandran ,&nbsp;Per Skallerup ,&nbsp;Stig M. Thamsborg ,&nbsp;Peter Nejsum","doi":"10.1016/j.ijpara.2024.08.001","DOIUrl":"10.1016/j.ijpara.2024.08.001","url":null,"abstract":"<div><div>The intestinal helminth <em>Ascaris lumbricoides</em> infects over 800 million people. Infections are often chronic and immunity is not sterilizing due to host-immune modulation, therefore reinfection is common after antihelmintic treatment. We have previously demonstrated a role for <em>Ascaris</em> spp. extracellular vesicles (EVs) in host immune modulation but whether EVs are recognized by the adaptive immune system and are present systemically in the host remains unknown. Therefore, we employed a well-established trickle infection model in pigs to mimic natural <em>Ascaris</em> infection in humans. EVs were isolated from adult <em>Ascaris suum</em> followed by immunoblotting of EV and EV-depleted secretory fractions using plasma from infected and uninfected pigs. Next, EVs were isolated from pig plasma at day 56 post first infection and subjected to deep small RNAseq analysis. RNAs were aligned to <em>A. suum</em> and <em>Sus scrofa</em> miRNA complements to detect <em>A. suum</em> EVs and elucidate the host EV micro RNA (miRNA) response to infection, respectively. Infection generates robust antibody responses against <em>A. suum</em> EVs that is distinct from EV-depleted fractions. However, <em>A. suum</em> miRNAs were not detectable in EVs from the peripheral blood. Notably, host plasma-derived EV miRNA profiles showed significant changes between infected and uninfected pigs, indicating that <em>Ascaris</em> infection drives systemic changes in host EV composition.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 13","pages":"Pages 691-696"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141906580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DNA N-glycosylases Ogg1 and EndoIII as components of base excision repair in Plasmodium falciparum organelles","authors":"Anupama Tiwari ,&nbsp;Neetu Verma ,&nbsp;Himadri Shukla ,&nbsp;Shivani Mishra ,&nbsp;Kit Kennedy ,&nbsp;Tribeni Chatterjee ,&nbsp;Jitendra Kuldeep ,&nbsp;Shahid Parwez ,&nbsp;MI Siddiqi ,&nbsp;Stuart A. Ralph ,&nbsp;Satish Mishra ,&nbsp;Saman Habib","doi":"10.1016/j.ijpara.2024.06.005","DOIUrl":"10.1016/j.ijpara.2024.06.005","url":null,"abstract":"<div><div>The integrity of genomes of the two crucial organelles of the malaria parasite — an apicoplast and mitochondrion in each cell − must be maintained by DNA repair mediated by proteins targeted to these compartments. We explored the localisation and function of <em>Plasmodium falciparum</em><span> base excision repair (BER) DNA N-glycosylase homologs </span><em>Pf</em>EndoIII and <em>Pf</em>Ogg1. These N-glycosylases would putatively recognise DNA lesions prior to the action of apurinic/apyrimidinic (AP)-endonucleases. Both Ape1 and Apn1 endonucleases have earlier been shown to function solely in the parasite mitochondrion. Immunofluorescence localisation showed that <em>Pf</em>EndoIII was exclusively mitochondrial. <em>Pf</em>Ogg1 was not seen clearly in mitochondria when expressed as a <em>Pf</em>Ogg1_leader-GFP fusion, although chromatin immunoprecipitation assays showed that it could interact with both mitochondrial and apicoplast DNA. Recombinant <em>Pf</em>EndoIII functioned as a DNA N-glycosylase as well as an AP-lyase on thymine glycol (Tg) lesions. We further studied the importance of Ogg1 in the malaria life cycle using reverse genetic approaches in <em>Plasmodium berghei</em>. Targeted disruption of <em>Pb</em>Ogg1 resulted in loss of 8-oxo-G specific DNA glycosylase/lyase activity. <em>Pb</em>Ogg1 knockout did not affect blood, mosquito or liver stage development but caused reduced blood stage infection after inoculation of sporozoites in mice. A significant reduction in erythrocyte infectivity by <em>Pb</em>Ogg1 knockout hepatic merozoites was also observed, thus showing that <em>Pb</em>Ogg1 ensures smooth transition from liver to blood stage infection. Our results strengthen the view that the <em>Plasmodium</em><span> mitochondrial genome is an important site for DNA repair by the BER pathway.</span></div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 13","pages":"Pages 675-689"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141534413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The concentration McMaster method for diagnosis of patent Ascaris and Trichuris infections in humans","authors":"Sozan Kader ,&nbsp;Christine E. Helmersen ,&nbsp;Stig M. Thamsborg ,&nbsp;Lise T. Erikstrup ,&nbsp;Peter Nejsum","doi":"10.1016/j.ijpara.2024.08.004","DOIUrl":"10.1016/j.ijpara.2024.08.004","url":null,"abstract":"<div><div>In tropical and subtropical regions, soil-transmitted helminth (STH) infections such as <em>Ascaris lumbricoides</em>, <em>Trichuris trichiura</em>, and hookworms have a significant impact on public health. Globally, <em>A. lumbricoides</em> infects approximately 0.8 billion people, while <em>T. trichiura</em> infects around 500 million. This study involved a comparison of three diagnostic methods, Kato-Katz and two flotation methods (concentration McMaster, and simple McMaster), for the detection of <em>Ascaris</em> and <em>Trichuris</em> in human faeces. We conducted a comparison of the number of eggs in faeces (or faecal egg counts (FECs)) obtained with these methods using freshly collected samples that were positive for <em>T. trichiura</em> and spiked with a known quantity of <em>Ascaris</em> sp. eggs. Additionally, for the concentration McMaster method we assessed FECs after storing the samples at 5 °C for up to 21 days. The concentration McMaster method demonstrated superiority over the simple McMaster method in terms of higher detection levels for both helminths, while the Kato-Katz method yielded FEC values very close to the ’true’ spiking values. Importantly, the concentration McMaster method was considerably easier to read compared with the Kato-Katz method, and it allowed for sample storage at 5 °C for up to 14 days without affecting FEC results. Consequently, we conclude that the concentration McMaster method is an effective and user-friendly alternative for diagnosis of <em>Ascaris</em> and <em>Trichuris</em> infections in humans. Furthermore, it offers the advantage of sample storage before analysis, enhancing flexibility in the workflow.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"54 13","pages":"Pages 717-722"},"PeriodicalIF":3.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142107085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}