Publications by authors named "Heidrun von Thien"

The pathogenesis of severe malaria involves cytoadhesive microvascular sequestration of infected erythrocytes, mediated by erythrocyte membrane protein 1 (PfEMP1). PfEMP1 variants are encoded by the highly polymorphic family of genes, the sequences of which are largely unknown in clinical samples. Previously, we published new approaches for gene profiling and classification of predicted binding phenotypes in clinical isolates (Wichers et al.

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Controlled human malaria infections (CHMI) are a valuable tool to study parasite gene expression in vivo under defined conditions. In previous studies, virulence gene expression was analyzed in samples from volunteers infected with the Plasmodium falciparum (Pf) NF54 isolate, which is of African origin. Here, we provide an in-depth investigation of parasite virulence gene expression in malaria-naïve European volunteers undergoing CHMI with the genetically distinct Pf 7G8 clone, originating in Brazil.

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Article Synopsis
  • - The study highlights the need to shift schistosomiasis control programs from focusing solely on school-aged children to include adults, which is crucial for eliminating the disease and achieving universal health coverage by 2030.
  • - Conducted in Madagascar, the research involved 1,482 adults, revealing high prevalence rates of schistosomiasis, particularly among males and those contributing to family income, with protective factors identified as being older and not working as a farmer.
  • - The findings indicate that adults represent a significant risk group for schistosomiasis, suggesting that public health strategies should adopt a more comprehensive approach to better address the needs of all affected populations.
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Malaria is responsible for hundreds of thousands of deaths every year. The lack of an effective vaccine and the global spread of multidrug resistant parasites hampers the fight against the disease and underlines the need for new antimalarial drugs. Central to the pathogenesis of malaria is the proliferation of Plasmodium parasites within human erythrocytes.

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Membrane transport proteins perform crucial roles in cell physiology. The obligate intracellular parasite Plasmodium falciparum, an agent of human malaria, relies on membrane transport proteins for the uptake of nutrients from the host, disposal of metabolic waste, exchange of metabolites between organelles, and generation and maintenance of transmembrane electrochemical gradients for its growth and replication within human erythrocytes. Despite their importance for cellular physiology, the functional roles of a number of membrane transport proteins remain unclear, which is particularly true for orphan membrane transporters that have no or limited sequence homology to transporter proteins in other evolutionary lineages.

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Intraerythrocytic malaria parasites proliferate bounded by a parasitophorous vacuolar membrane (PVM). The PVM contains nutrient permeable channels (NPCs) conductive to small molecules, but their relevance for parasite growth for individual metabolites is largely untested. Here we show that growth-relevant levels of major carbon and energy sources pass through the NPCs.

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During the symptomatic human blood phase, malaria parasites replicate within red blood cells. Parasite proliferation relies on the uptake of nutrients, such as amino acids, from the host cell and blood plasma, requiring transport across multiple membranes. Amino acids are delivered to the parasite through the parasite-surrounding vacuolar compartment by specialized nutrient-permeable channels of the erythrocyte membrane and the parasitophorous vacuole membrane (PVM).

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Sequestration of ()-infected erythrocytes to host endothelium through the parasite-derived erythrocyte membrane protein 1 (EMP1) adhesion proteins is central to the development of malaria pathogenesis. EMP1 proteins have diversified and expanded to encompass many sequence variants, conferring each parasite a similar array of human endothelial receptor-binding phenotypes. Here, we analyzed RNA-seq profiles of parasites isolated from 32 infected adult travellers returning to Germany.

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The inner membrane complex (IMC) is a defining feature of apicomplexan parasites, which confers stability and shape to the cell, functions as a scaffolding compartment during the formation of daughter cells and plays an important role in motility and invasion during different life cycle stages of these single-celled organisms. To explore the IMC proteome of the malaria parasite Plasmodium falciparum we applied a proximity-dependent biotin identification (BioID)-based proteomics approach, using the established IMC marker protein Photosensitized INA-Labelled protein 1 (PhIL1) as bait in asexual blood-stage parasites. Subsequent mass spectrometry-based peptide identification revealed enrichment of 12 known IMC proteins and several uncharacterized candidate proteins.

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Background: Over the last two decades, a significant spread of dirofilariasis has been observed in eastern and central Europe. However, data on the circulation of Dirofilaria spp. in Moldova were absent although direct neighbor states reported high incidence rates of human dirofilariasis.

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During the last two decades, Belarus faces an increase of human cases of Dirofilaria (Nematoda, Spirurida, Onchocercidae) infections. However, comprehensive analyses explaining this development and the identification of mosquito vector species are missing. Here, we present results using temperature data from Belarus and show that the annual number of human Dirofilaria cases is significantly correlated with the yearly average temperatures (Spearman's rho = 0.

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Mosquitoes and other arthropods may transmit medically important pathogens, in particular viruses such as West Nile virus. The presence of suitable hosts and competent vectors for those zoonotic viruses is essential for an enzootic transmission, which is a prerequisite for epidemics. To establish reliable risk projections, it is an urgent need for an exact identification of mosquito species, which is especially challenging in the case of sibling species, such as Culex.

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Background: Acute schistosomiasis constitutes a rare but serious condition in individuals experiencing their first prepatent Schistosoma infection. To circumvent costly and time-consuming diagnostics, an early and rapid diagnosis is required. So far, classic diagnostic tools such as parasite microscopy or serology lack considerable sensitivity at this early stage of Schistosoma infection.

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Diarrhea is an important cause of morbidity and mortality, worldwide. Giardia intestinalis, Cryptosporidium spp., and Entamoeba histolytica are the most common diarrhea-causing parasitic protozoa.

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A novel fecal antigen detection assay for fresh and frozen human samples that detects but does not differentiate Giardia spp, Cryptosporidium spp, and Entamoeba histolytica, the Tri-Combo parasite screen, was compared to three established enzyme-linked immunosorbent assays (ELISAs) at three international sites. It exhibited 97.9% sensitivity and 97.

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Malaria remains the single most frequent cause of death in Africa, killing one child every 30 s, but treatment decisions are often made only on clinical diagnosis, as laboratory techniques to confirm the clinical suspicion are labor intensive and costly. In this study, we evaluated the recently developed Partec rapid malaria test (PM) for the detection of Plasmodium spp. in human blood from patients in an area where malaria is endemic and compared the results with those of thick blood film Giemsa stain (GS) in terms of its performance and operational characteristics, using real-time (RT) PCR as the gold standard.

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