Lack of Competence of US Mosquito Species for Circulating Oropouche Virus.

Given recent outbreaks of Oropouche virus in Latin America and >100 confirmed travel-associated cases in the United States, we evaluated the competence of US vectors, including Aedes albopictus, Culex quinquefasciatus, Culex pipiens, and Anopheles quadrimaculatus mosquitoes. Results with historic and recent isolates suggest transmission potential for those species is low.

Oropouche Virus Disease Among U.S. Travelers - United States, 2024.

Beginning in late 2023, Oropouche virus was identified as the cause of large outbreaks in Amazon regions with known endemic transmission and in new areas in South America and the Caribbean. The virus is spread to humans by infected biting midges and some mosquito species. Although infection typically causes a self-limited febrile illness, reports of two deaths in patients with Oropouche virus infection and vertical transmission associated with adverse pregnancy outcomes have raised concerns about the threat of this virus to human health.

Fatty acid elongases 1-3 have distinct roles in mitochondrial function, growth, and lipid homeostasis in Trypanosoma cruzi.

Trypanosomatids are a diverse group of uniflagellate protozoan parasites that include globally relevant pathogens such as Trypanosoma cruzi, the causative agent of Chagas disease. Trypanosomes lack the fatty acid synthase system typically used for de novo fatty acid (FA) synthesis in other eukaryotes. Instead, these microbes have evolved a modular FA elongase (ELO) system comprised of individual ELO enzymes (ELO1-4) that can operate processively to generate long chain- and very long chain-FAs.

Endogenous Sterol Synthesis Is Dispensable for Epimastigote Growth but Not Stress Tolerance.

In addition to scavenging exogenous cholesterol, the parasitic kinetoplastid can endogenously synthesize sterols. Similar to fungal species, synthesizes ergostane type sterols and is sensitive to a class of azole inhibitors of ergosterol biosynthesis that target the enzyme lanosterol 14α-demethylase (CYP51). In the related kinetoplastid parasite , CYP51 is essential, yet in , the cognate enzyme is dispensable for growth; but not heat resistance.

Metabolic flexibility in Trypanosoma cruzi amastigotes: implications for persistence and drug sensitivity.

Throughout their life cycle, parasitic organisms experience a variety of environmental conditions. To ensure persistence and transmission, some protozoan parasites are capable of adjusting their replication or converting to distinct life cycle stages. Trypanosoma cruzi is a 'generalist' parasite that is competent to infect various insect (triatomine) vectors and mammalian hosts.

Glutamine metabolism modulates azole susceptibility in amastigotes.

The mechanisms underlying resistance of the Chagas disease parasite, to current therapies are not well understood, including the role of metabolic heterogeneity. We found that limiting exogenous glutamine protects actively dividing amastigotes from ergosterol biosynthesis inhibitors (azoles), independent of parasite growth rate. The antiparasitic properties of azoles are derived from inhibition of lanosterol 14α-demethylase (CYP51) in the endogenous sterol synthesis pathway.

Methods for the Investigation of Trypanosoma cruzi Amastigote Proliferation in Mammalian Host Cells.

In its mammalian host, the kinetoplastid protozoan parasite, Trypanosoma cruzi, is obliged to establish intracellular residence in order to replicate. This parasite can infect and replicate within a diverse array of cell and tissue types across many mammalian host species. The establishment of quantitative assays to assess the replicative capacity of intracellular T.

A Novel Antiparasitic Compound Kills Ring-Stage Plasmodium falciparum and Retains Activity Against Artemisinin-Resistant Parasites.

Spreading antimalarial resistance threatens effective treatment of malaria, an infectious disease caused by Plasmodium parasites. We identified a compound, BCH070, that inhibits asexual growth of multiple antimalarial-resistant strains of Plasmodium falciparum (half maximal inhibitory concentration [IC50] = 1-2 µM), suggesting that BCH070 acts via a novel mechanism of action. BCH070 preferentially kills early ring-form trophozoites, and, importantly, equally inhibits ring-stage survival of wild-type and artemisinin-resistant parasites harboring the PfKelch13:C580Y mutation.

Generation of Transmission-Competent Human Malaria Parasites with Chromosomally-Integrated Fluorescent Reporters.

Malaria parasites have a complex life cycle that includes specialized stages for transmission between their mosquito and human hosts. These stages are an understudied part of the lifecycle yet targeting them is an essential component of the effort to shrink the malaria map. The human parasite Plasmodium falciparum is responsible for the majority of deaths due to malaria.

Stress-Induced Proliferation and Cell Cycle Plasticity of Intracellular Amastigotes.

The mammalian stages of the parasite , the causative agent of Chagas disease, exhibit a wide host species range and extensive within-host tissue distribution. These features, coupled with the ability of the parasites to persist for the lifetime of the host, suggest an inherent capacity to tolerate changing environments. To examine this potential, we studied proliferation and cell cycle dynamics of intracellular amastigotes experiencing transient metabolic perturbation or drug pressure in the context of an infected mammalian host cell.

Host triacylglycerols shape the lipidome of intracellular trypanosomes and modulate their growth.

Intracellular infection and multi-organ colonization by the protozoan parasite, Trypanosoma cruzi, underlie the complex etiology of human Chagas disease. While T. cruzi can establish cytosolic residence in a broad range of mammalian cell types, the molecular mechanisms governing this process remain poorly understood.

Modulation of host central carbon metabolism and in situ glucose uptake by intracellular Trypanosoma cruzi amastigotes.

Obligate intracellular pathogens satisfy their nutrient requirements by coupling to host metabolic processes, often modulating these pathways to facilitate access to key metabolites. Such metabolic dependencies represent potential targets for pathogen control, but remain largely uncharacterized for the intracellular protozoan parasite and causative agent of Chagas disease, Trypanosoma cruzi. Perturbations in host central carbon and energy metabolism have been reported in mammalian T.

Bioenergetic profiling of Trypanosoma cruzi life stages using Seahorse extracellular flux technology.

Energy metabolism is an attractive target for the development of new therapeutics against protozoan pathogens, including Trypanosoma cruzi, the causative agent of human Chagas disease. Despite emerging evidence that mitochondrial electron transport is essential for the growth of intracellular T. cruzi amastigotes in mammalian cells, fundamental knowledge of mitochondrial energy metabolism in this parasite life stage remains incomplete.

Impact of the post-weaning nutritional history on the response to an experimental Haemonchus contortus infection in Creole goats and Black Belly sheep.

In small ruminants, the response against gastrointestinal nematode (GIN) infections is influenced not only by the host genotype and the physiological stage but also by environmental factors, particularly the nutritional status at the time of infection. In this study we evaluated the long-term effect and the interaction between the host species and the nutritional history on the response to GIN infection in two animal models differing in their phenotypic growth and their level of GIN resistance: Black Belly sheep and Creole goats. Lambs and kids were subjected to three distinct nutritional conditions at weaning: low dietary conditions (100% of the theoretical energy requirement for maintenance, corresponding to 548v.

Flow Cytometry Based Detection and Isolation of Plasmodium falciparum Liver Stages In Vitro.

Malaria, the disease caused by Plasmodium parasites, remains a major global health burden. The liver stage of Plasmodium falciparum infection is a leading target for immunological and pharmacological interventions. Therefore, novel approaches providing specific detection and isolation of live P.

Dynamics of the major histocompatibility complex class I processing and presentation pathway in the course of malaria parasite development in human hepatocytes: implications for vaccine development.

Control of parasite replication exerted by MHC class I restricted CD8+ T-cells in the liver is critical for vaccination-induced protection against malaria. While many intracellular pathogens subvert the MHC class I presentation machinery, its functionality in the course of malaria replication in hepatocytes has not been characterized. Using experimental systems based on specific identification, isolation and analysis of human hepatocytes infected with P.

Effect of experimental infection with Haemonchus contortus on parasitological and local cellular responses in resistant and susceptible young Creole goats.

This study was carried out to evaluate the relationships of cellular changes in the abomasal mucosa and parasitological parameters, by comparing resistant and susceptible young Creole goats (kids) after experimental infection with Haemonchus contortus. The kids were infected over 2 periods (challenges 1 and 2) of 7 and 6 weeks, respectively. Fecal egg count (FEC), blood eosinophilia, packed cell volume (PCV), and body weight were weekly monitored.

Various PfRH5 polymorphisms can support Plasmodium falciparum invasion into the erythrocytes of owl monkeys and rats.

Aotus nancymaae, the owl monkey, provides a useful laboratory model for research to develop drugs and vaccines against human falciparum malaria; however, many Plasmodium falciparum parasites are unable to invade A. nancymaae erythrocytes, rendering the parasites noninfective to the monkeys. In previous work, we identified a key polymorphism that determined the inheritance of erythrocyte invasion in a genetic cross of two P.

A fast and cost-effective approach to develop and map EST-SSR markers: oak as a case study.

Background: Expressed Sequence Tags (ESTs) are a source of simple sequence repeats (SSRs) that can be used to develop molecular markers for genetic studies. The availability of ESTs for Quercus robur and Quercus petraea provided a unique opportunity to develop microsatellite markers to accelerate research aimed at studying adaptation of these long-lived species to their environment. As a first step toward the construction of a SSR-based linkage map of oak for quantitative trait locus (QTL) mapping, we describe the mining and survey of EST-SSRs as well as a fast and cost-effective approach (bin mapping) to assign these markers to an approximate map position.

Fatal hypoxic hepatitis in a patient with hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber's disease).

Hypoxic (ischemic) hepatitis generally requires the concurrence of an underlying condition which chronically exposes the liver to some degree of hypoxia (for example, congestive heart failure) combined with a triggering event (for example, arrhythmia) which further decreases the oxygen supply. We report a case of hypoxic hepatitis in which hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber's disease) constituted this underlying condition and gastrointestinal hemorrhage was the triggering event. To our knowledge, this is the first reported case of hypoxic hepatitis in hereditary hemorrhagic telangiectasia with the exception of therapeutic ligation or embolization of the hepatic artery so as to decrease shunting of liver blood.

[Systemic hypertension and sports practice. Epidemiology and therapeutics].

Hypertension, the most common cardiovascular disorder, also affects patients who want to practice a sport. Before counselling them, the physician should know the acute and chronic physiological effects of various sports. Is the activity authorised in a hypertensive? Yes, some physical activities are recommended and contribute to lower blood pressure readings.

A novel EH domain protein of Saccharomyces cerevisiae, Ede1p, involved in endocytosis.

Sequencing of the entire genome of S. cerevisiae has revealed the existence of five proteins containing EH domains. These are protein-protein interaction modules first described in mammalian Eps15, a protein that is involved in clathrin-dependent endocytosis.

Functional analysis of six genes from chromosomes XIV and XV of Saccharomyces cerevisiae reveals YOR145c as an essential gene and YNL059c/ARP5 as a strain-dependent essential gene encoding nuclear proteins.

We report here basic functional analysis of strains deleted for six open reading frames (ORFs), YNL059c and YNL148c from chromosome XIV and YOR145c, YOR152c, YOR161c and YOR162c from chromosome XV of Saccharomyces cerevisiae. ORFs were replaced with the KanMX4 resistance marker using a long flanking homology PCR strategy in FY1679 and W303 diploid strains. Replacement cassettes were constructed in plasmid pUG7 and the cognate wild-type genes were recovered by gap repair.