Publications by authors named "Radek Sima"

Syphilis, known as "the great mimicker," is caused by the spirochete Treponema pallidum and is characterized by a diverse array of clinical and histopathologic presentations. In secondary cutaneous syphilis, the most consistent morphological features include a superficial and deep perivascular infiltrate containing plasma cells, varying degrees of endothelial swelling, irregular acanthosis, elongation of rete ridges, a vacuolated pattern, and the presence of plasma cells. Although serologic tests are essential for definitive diagnosis, spirochetes can sometimes be directly identified in silver-stained tissue slides or through immunohistochemistry.

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  • Adenoid cystic carcinomas (AdCC) of salivary gland origin are primarily defined by the presence of specific gene fusions, notably MYB::NFIB and MYBL1::NFIB, with sinonasal AdCC being particularly aggressive and lacking effective treatments.
  • Researchers conducted an extensive analysis of 88 sinonasal AdCC cases using various techniques like NGS and FISH to identify gene fusions and mutations, finding that the majority harbored canonical fusions while some had noncanonical ones, with a few tumors showing no fusions at all.
  • Mutational analysis revealed that about 68% of AdCCs tested (21 out of 31) had mutations in key oncogenes, highlighting potential areas for targeted
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  • Aedes aegypti mosquitoes are key carriers of dengue, and factors like urbanization, climate change, and trade are affecting their populations.
  • Higher temperatures have been shown to impact insect mortality and fertility, with this study focusing on how heat influences the fertility of Ae. aegyti across different generations.
  • Results indicated that while mosquitoes can acclimate to heat, their fertility declines with increasing temperatures, affecting both male and female mosquitoes’ ability to reproduce and produce viable offspring, which could impact their populations in warmer climates.
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The vector competence of blood-feeding arthropods is influenced by the interaction between pathogens and the immune system of the vector. The Toll and IMD (immune deficiency) signaling pathways play a key role in the regulation of innate immunity in both the Drosophila model and blood-feeding insects. However, in ticks (chelicerates), immune determination for pathogen acquisition and transmission has not yet been fully explored.

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Lyme disease, a tick-borne illness caused by spirochetes, poses a significant threat to public health. While acaricides effectively control ticks on pets and livestock, their impact on pathogen transmission is often unclear. This study investigated the acaricidal efficacy of fipronil against ticks and its potential to block transmission.

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The structure and biochemical properties of protease inhibitors from the thyropin family are poorly understood in parasites and pathogens. Here, we introduce a novel family member, Ir-thyropin (IrThy), which is secreted in the saliva of ticks, vectors of Lyme borreliosis and tick-borne encephalitis. The IrThy molecule consists of two consecutive thyroglobulin type-1 (Tg1) domains with an unusual disulfide pattern.

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Ticks are ectoparasites that feed on blood and have an impressive ability to consume and process enormous amounts of host blood, allowing extremely long periods of starvation between blood meals. The central role in the parasitic lifestyle of ticks is played by the midgut. This organ efficiently stores and digests ingested blood and serves as the primary interface for the transmission of tick-borne pathogens.

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Background: Ticks can transmit a broad variety of pathogens of medical importance, including Borrelia afzelii, the causative agent of Lyme borreliosis in Europe. Tick microbiota is an important factor modulating, not only vector physiology, but also the vector competence. Anti-microbiota vaccines targeting keystone taxa of tick microbiota can alter tick feeding and modulate the taxonomic and functional profiles of bacterial communities in the vector.

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Methylation silencing of certain cellular genes is a sign of carcinogenesis progression and therefore tests that detect methylation could be used in the diagnosis or staging of malignant diseases. In the diagnosis of squamous cell carcinomas of the cervix which are almost 100% caused by long-term infection with highrisk human papillomavirus (HR-HPV), methylation silencing of certain cellular genes is a highly specific marker of advanced dysplastic lesions and appears to result from aberrant activation of the methyltransferase DNMT1 by viral oncoproteins E6 and E7. A methylation test performed on a cervicovaginal cytology specimen allows to increase the diagnostic value of this non-invasive test and to select patients with severe squamous cell lesions for follow-up.

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Introduction: Borrelia burgdorferi sensu lato, the causative agents of Lyme borreliosis, are transmitted by Ixodes ticks. Tick saliva proteins are instrumental for survival of both the vector and spirochete and have been investigated as targets for vaccine targeting the vector. In Europe, the main vector for Lyme borreliosis is Ixodes ricinus, which predominantly transmits Borrelia afzelii.

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Ixodes ricinus and Ixodes scapularis are the main vectors for the causative agents of Lyme borreliosis and a wide range of other pathogens. Repeated tick-bites are known to lead to tick rejection; a phenomenon designated as tick immunity. Tick immunity is mainly directed against tick salivary gland proteins (TSGPs) and has been shown to partially protect against experimental Lyme borreliosis.

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is the causative agent of tick-borne fever (TBF) and human granulocytic anaplasmosis (HGA) and is currently considered an emerging disease in the USA, Europe, and Asia. The increased prevalence of as a human pathogen requires the detailed characterization of human isolates and the implementation of appropriate animal models. In this study, we demonstrated that the dynamics of infection with the human isolate of NY-18 was variable in three different strains of mice (SCID, C3H/HeN, BALB/c).

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It has been demonstrated that impairing protein synthesis using drugs targeted against tRNA amino acid synthetases presents a promising strategy for the treatment of a wide variety of parasitic diseases, including malaria and toxoplasmosis. This is the first study evaluating tRNA synthetases as potential drug targets in ticks. RNAi knock-down of all tested tRNA synthetases had a strong deleterious phenotype on feeding.

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An anti-tick mRNA cocktail vaccine promotes tick detachment and prevents transmission of tick-borne infection in guinea pigs (Sajid ).

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In Europe, Ixodes ricinus is the most important vector of human infectious diseases, most notably Lyme borreliosis and tick-borne encephalitis virus. Multiple non-natural hosts of I. ricinus have shown to develop immunity after repeated tick bites.

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Lyme borreliosis is an emerging tick-borne disease caused by spirochetes sensu lato. In Europe, Lyme borreliosis is predominantly caused by and transmitted by . Although behavior throughout tick development is quite well documented, specific molecular interactions between and the tick have not been satisfactorily examined.

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Ixodes ricinus is the vector for Borrelia afzelii, the predominant cause of Lyme borreliosis in Europe, whereas Ixodes scapularis is the vector for Borrelia burgdorferi in the USA. Transcription of several I. scapularis genes changes in the presence of B.

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Regulatory factors controlling tick salivary glands (SGs) are direct upstream neural signaling pathways arising from the tick's central nervous system. Here we investigated the cholinergic signaling pathway in the SG of two hard tick species. We reconstructed the organization of the cholinergic gene locus, and then used in situ hybridization to localize mRNA encoding choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT) in specific neural cells in the Ixodes synganglion.

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A growing global health concern, Lyme disease has become the most common tick-borne disease in the United States and Europe. Caused by the bacterial spirochete sensu lato (sl), this disease can be debilitating if not treated promptly. Because diagnosis is challenging, prevention remains a priority; however, a previously licensed vaccine is no longer available to the public.

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Epigenetic mechanisms have not been characterized in ticks despite their importance as vectors of human and animal diseases worldwide. Our investigation identifies and functionally characterizes the orthologue of S-adenosylmethionine (SAM) binding methyltransferase enzyme, disruptor of telomeric silencing 1-like (DOT1L) in Ornithodoros moubata (OmDOT1L), a soft tick vector for the relapsing fever pathogen Borrelia duttonii and the African swine fever virus. The OmDOT1L tertiary structure was predicted and compared to the Homo sapiens DOT1L which had been co-crystalized with SGC0946, a DOT1L-specific inhibitor.

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Article Synopsis
  • Myxozoans are diverse endoparasites linked to serious fish diseases, and new gene expression techniques are being used to understand and manage these diseases.
  • A major focus of the study is the accuracy of gene expression measurements, which relies on normalizing data against reference genes.
  • The researchers analyzed eight common reference genes and found that GAPDH and EF2 were the most consistently expressed across different developmental stages in three key myxozoan species.
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Hematophagous arthropods are responsible for the transmission of a variety of pathogens that cause disease in humans and animals. Ticks of the Ixodes ricinus complex are vectors for some of the most frequently occurring human tick-borne diseases, particularly Lyme borreliosis and tick-borne encephalitis virus (TBEV). The search for vaccines against these diseases is ongoing.

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Background: Sphaerospora molnari is a myxozoan parasite causing skin and gill sphaerosporosis in common carp (Cyprinus carpio) in central Europe. For most myxozoans, little is known about the early development and the expansion of the infection in the fish host, prior to spore formation. A major reason for this lack of information is the absence of laboratory model organisms, whose life-cycle stages are available throughout the year.

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