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COLLECTION AND EXAMINATION OF SMALL-BODIED, FRESHWATER FISH FOR HELMINTH PARASITES.

Small-bodied, freshwater fish are often used in parasitological studies because they host a variety of parasites. As a result, it is importa … ry collections are also a source of small-bodied fish hosts that can be used to describe historical host-parasite interactions and changes in parasite communities. However, using natural history collections presents issues that require careful consideration, including what specimens are available, where the specimens are housed, obtaining permission from curators, and perfo …

Fecal shedding level of Haemonchus contortus is associated with gastrointestinal bacterial microbial composition in naturally infected sheep.

A complex interaction of gastrointestinal parasites with sheep hosts may involve bacteria communities, parasite genera, parasitic genes, and biological pathways. Haemonchus contortus presents a global challenge for ruminants, and the bacterial community can influence sheep's resistance and susceptibility to these parasites. Thus, a better understanding of this complex interaction could contribute to the development of a new approach to parasite control. This study evaluated the bacterial community of Corriedale sheep naturally infected with H. contortus based on the fecal egg counts over ten m

Необычный двухгранный фиропин от Тика Саливы: структура решения NMR и высокоселективное ингибирование Cystein Cthepsins Moduled by Glycosaminoglycans.

Структурные и биохимические свойства ингибиторов выступов из семейства тиропинов плохо понимаются у паразитов и патогенов. Здесь мы представляем нового члена семьи Ир-тиропина (IrThy), который скрыт в слюне рикодовых клещей, векторов боррилеза Лайма и трансмисситного энцефалита. Молекулярная молекула IrThy состоит из двух последовательных тироглобулинов типа 1 (Tg1) с необычным дисульфидом. Было установлено, что рекомбинант Ирти препятствует выступам катепсина из человека с высокой спецификой для катепсинов V, K и L среди широкого круга катепсинов с различными эндо- и экопептидазами. Оба домен

Совпадение в аннотации оригинала
The structure and biochemical properties of protease inhibitors from the thyropin family are poorly understood in parasites and pathogens. H … tion of IrThy-the first investigated thyropin of parasite origin-and suggests its potential role in host-parasite interactions at the tick bite site.

Characterization of a novel glycosylated glutathione transferase of Onchocerca ochengi, closest relative of the human river blindness parasite.

Filarial nematodes possess glutathione transferases (GSTs), ubiquitous enzymes with the potential to detoxify xenobiotic and endogenous subs … e second reported and characterized glycosylated GST and our study highlights its potential role in host-parasite interactions and use in the study of human onchocerciasis.

Cryptosporidium pathogenicity and virulence.

Cryptosporidium is a protozoan parasite of medical and veterinary importance that causes gastroenteritis in a variety of vertebrate hosts. Several studies have reported different degrees of pathogenicity and virulence among Cryptosporidium species and isolates of the same species as well as evidence of variation in host susceptibility to infection. The identification and validation of Cryptosporidium virulence factors have been hindered by the renowned difficulties pertaining to the in vitro culture and genetic manipulation of this parasite. Nevertheless, substantial progress has been made in

Gastrointestinal parasites in free-ranging common marmosets (Callithrix jacchus Linnaeus, 1758) in the state of Sergipe, northeastern Brazil.

Ecological interactions resulting from human interference and environmental changes have implications for human health and the host animals involved in the parasite cycles. Considering the scarcity of surveys of the parasitic fauna of non-human primates in northeastern Brazil, the objective of this study was to investigate the infection by gastrointestinal parasites in free-ranging common marmosets (Callithrix jacchus) in the State of Sergipe. Fecal samples were collected from 52 animals captured in three protected areas. Most of the samples consisted of adult females and 57% were infected wit

What's eating you? An update on Giardia, the microbiome and the immune response.

Giardia intestinalis has been observed in human stools since the invention of the microscope. However, it was not recognized as a pathogen until experimental infections in humans in the 1950s resulted in diarrheal illness [1]. We now know that this protozoan is capable of inducing a malabsorptive diarrhea and that the parasite is a major contributor to stunting in young children [2]. However, the majority of infections with this parasite are not accompanied by overt diarrhea and several studies indicate that it actually has a protective effect against moderate-severe diarrhea [3]. There is the

Oxidative and nitrosative stresses in cerebral malaria: can we target them to avoid a bad prognosis?

There is currently a global effort to reduce malaria morbidity and mortality. However, malaria still results in the deaths of thousands of p … scuss the roles of reactive oxygen species and reactive nitrogen intermediates in CM as a result of host-parasite interactions. We also present evidence of the potential contribution of oxidative and nitrosative stress-based antimalarial drugs to disease treatment and control.

Microglia in neuropathology caused by protozoan parasites.

Involvement of the central nervous system (CNS) is the most severe consequence of some parasitic infections. Protozoal infections comprise a group of diseases that together affect billions of people worldwide and, according to the World Health Organization, are responsible for more than 500000 deaths annually. They include African and American trypanosomiasis, leishmaniasis, malaria, toxoplasmosis, and amoebiasis. Mechanisms underlying invasion of the brain parenchyma by protozoa are not well understood and may depend on parasite nature: a vascular invasion route is most common. Immunosuppress

Toxoplasma effector Tg WIP hijacks dendritic cell actin and motility via Nck1/Grb2 and the WAVE complex.

The intracellular parasite Toxoplasma gondii enhances its dissemination to distant organs by hijacking infected leukocytes via a Trojan Horse mechanism. Upon infecting dendritic cells (DCs), Toxoplasma induces a hypermigratory phenotype characterized by podosome dissolution and formation of F-actin stress fibers. We previously showed that these cytoskeletal changes depend on the effector protein Toxoplasma WAVE complex-interacting protein ( Tg WIP) secreted from parasites to infected leukocytes. Here, we identify the host adaptor proteins Non-catalytic region of tyrosine kinase adaptor protein

Transcriptomic signatures differentiating carrier and dead-end fish hosts of proliferative kidney disease.

INTRODUCTION: Tetracapsuloides bryosalmonae is the causative agent of proliferative kidney disease (PKD) in salmonids. Brown trout function … s of host-specific outcomes in PKD and highlights the role of transcriptional regulation in shaping host-parasite interactions.

Brain endothelial spheroids and cortical organoids reveal the impact of Toxoplasma gondii lineage and host-phagocyte-pathogen interactions on colonization.

Toxoplasma gondii chronically infects the central nervous system (CNS), but the mechanisms enabling its traversal of the blood-brain barrier (BBB) remain unclear. Here, we investigated BBB penetration using brain endothelial spheroids and cerebral tissue-derived organoids that recapitulate three-dimensional barrier features. We show that T. gondii tachyzoites efficiently colonize spheroids, without detectable barrier disruption or obligatory parasite replication. Following direct transmigration, tachyzoites invaded and replicated within deeper cell layers. Type I strains (RH, CPS) exhibited hi

Comparative epidemiology of gastrointestinal parasites in cattle and buffalo under smallholder systems in Thailand.

Gastrointestinal parasite (GIP) infections significantly limit livestock productivity in tropical smallholder systems, yet comparative epidemiological data between cattle and buffalo remain scarce. This study examined co-infection dynamics, parasite patterns, and risk factors in cattle and buffalo in Thailand. A cross-sectional study of 302 animals (30 farms) used fecal examinations to detect nematodes, rumen flukes, and Fasciola spp. Risk factors were assessed using univariable and multivariable logistic regression. Animal-level GIP prevalence was 69.54% (buffalo 78.07%; cattle 64.36%), with

The parasitic fauna of the Chiloe wigeon Mareca sibilatrix (Anseriformes: Anatidae) from Ñuble region, Chile.

The Chiloe wigeon, Mareca sibilatrix (Anseriformes: Anatidae), is a native duck distributed mainly in Chile and Argentina. Although it is a common species in the Neotropical realm, studies on its parasitic fauna remain limited. This study aimed to gather additional data on host-parasite associations in M. sibilatrix. Thus, 18 birds from Ñuble region, central Chile, were subjected to parasitic examination. Ectoparasites and endoparasites obtained were stored in 70 % and 80 % ethanol, respectively. A total of 787 parasite individuals were isolated; all birds were parasitized by at least one para

Divergent Egg-Rejection Strategies Between Laying and Incubation Periods in the Green-Backed Tit (Parus monticolus).

Egg recognition and rejection constitute essential host defenses against brood parasitism, with rejection decisions reflecting evolutionary … trategies. Our findings offer important implications for understanding the evolutionary dynamics of host-parasite interactions and establish a framework for investigating recognition behaviors in other cavity-nesting hosts.

Plasticity and redundancy among AMA-RON pairs ensure host cell entry of Toxoplasma parasites.

Malaria and toxoplasmosis are infectious diseases caused by the apicomplexan parasites Plasmodium and Toxoplasma gondii, respectively. These parasites have developed an invasion mechanism involving the formation of a moving junction (MJ) that anchors the parasite to the host cell and forms a ring through which the parasite penetrates. The composition and the assembly of the MJ, and in particular the presence of protein AMA1 and its interaction with protein RON2 at the MJ, have been the subject of intense controversy. Here, using reverse genetics, we show that AMA1, a vaccine candidate, interac

Immunobiology of experimental cutaneous leishmaniasis.

The study of the murine model of infection with Leishmania major is providing important insights into the understanding of the complex interactions between the host and intracellular pathogens. Using this model system, basic research is actively leading to the identification of host factors promoting or circumventing the development of immunity to L. major. Here, Geneviève Milon, Giuseppe Del Giudice and Jacques A. Louis review recent results related to the characterization of immunological host factors determining resistance and susceptibility to this parasite, and try to identify areas where

Parasite-specific essential bromodomain protein TgBDP4 is a key epigenetic reader and a potential drug target for the parasite Toxoplasma gondii.

Toxoplasma gondii, an apicomplexan parasite, relies heavily on epigenetic regulation of gene expression, which is controlled by chromatin-modifying enzymes and histone acetylation, to invade and establish infection in the host. Bromodomain proteins are important epigenetic regulators in parasites, acting as "readers" of histone lysine acetylation to control gene expression. While many bromodomain proteins are unique to parasites, only a few have been explored for therapeutic applications. In this study, we characterized the parasite-specific bromodomain protein TgBDP4 as a key epigenetic reade

Toxoplasma GRA15 expression on dendritic cells inhibits B cell differentiation and antibody production.

One of the dense granule proteins named GRA15 in Toxoplasma gondii (T. gondii), is known to support an innate immune response in host through activation of NF-κB. However, little is known about advantages of GRA15 for parasites. By examining the role of GRA15 in the host-parasite interactions, it was clarified that GRA15 in T. gondii suppressed acquired immune responses in host. Wild-type parasite infection to C57BL/6 mice resulted in lower titers of T. gondii antibody and lower plasma cell counts compared to Δgra15 T. gondii. To identify host cells in which GRA15 acts to suppress antibody pro…

Conservation of CD4+ T cell-dependent developmental mechanisms in the blood fluke pathogens of humans.

Schistosoma blood flukes are trematode parasites with a cosmopolitan distribution that infect over 200 million people globally. We previously showed that Schistosoma mansoni growth and development in the mammalian host is dependent on signals from host CD4+ T cells. To gain insight into the mechanisms that underlie this dependence, we sought to determine the evolutionary origins and limits of this aspect of the host-pathogen relationship. By infecting RAG-1-/- mice with a range of different schistosome species and strains, we tested several hypotheses concerning the time during Schistosoma evo