Host preference
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The two stork species that nest in Central Europe, Ciconia ciconia and Ciconia nigra, have been repeatedly shown to host the digenetic trematode Cathaemasia hians (Rudolphi, 1809) in their esophagus and muscular stomach. These host species differ in their habitat and food preferences, and the morphologic characters of C. hians isolates ex Ci. nigra and Ci. ciconia are not identical. These differences led to a previous proposal of two subspecies, Cathaemasia hians longivitellata Macko, 1960, and Cathaemasia hians hians Macko, 1960. We hypothesize that the Cathaemasia hians isolates ex Ci. nigra and Ci. ciconia represent two independent species. Therefore, in the present study, we performed the first molecular analyses of C. hians individuals that were consistent with the diagnosis of C. hians hians (ex Ci. nigra) and C. hians longivitellata (ex Ci. ciconia). The combined molecular and comparative morphological analyses of the central European Cathaemasia individuals ex Ci. nigra and Ci. ciconia led to the proposal of a split of C. hians into C. hians sensu stricto (formerly C. hians hians) and C. longivitellata sp. n. (formerly C. hians longivitellata). Morphological analyses confirmed that the length of the vitellaria is the key identification feature of the two previously mentioned species. Both Cathaemasia spp. substantially differ at the molecular level and have strict host specificity, which might be related to differences in the habitat and food preferences of the two stork species.
The genomic signature of an organism captures the characteristics of repeated oligonucleotide patterns in its genome 1, such as oligomer frequencies, GC content, and differences in codon usage. Viruses, however, are obligate intracellular parasites that are dependent on their host cells for replication, and information about genomic signatures in viruses has hitherto been sparse.Here, we investigate the presence and specificity of genomic signatures in 2,768 eukaryotic viral species from 105 viral families, aiming to illuminate dependencies and selective pressures in viral genome evolution. We demonstrate that most viruses have highly specific genomic signatures that often also differ significantly between species within the same family. The species-specificity is most prominent among dsDNA viruses and viruses with large genomes. We also reveal consistent dissimilarities between viral genomic signatures and those of their host cells, although some viruses present slight similarities, which may be explained by genetic adaptation to their native hosts. Our results suggest that significant evolutionary selection pressures act upon viral genomes to shape and preserve their genomic signatures, which may have implications for the field of synthetic biology in the construction of live attenuated vaccines and viral vectors.
Myxozoans are microscopical parasites widely distributed in fish, with over 2,600 described species, but their actual diversity is still underestimated. Among salmonids, more than 70 myxozoan species have been identified. This study focuses on species of Chloromyxum Mingazzini, 1890 that infect salmonid kidneys, particularly C. majori Yasutake et Wood, 1957 and C. schurovi Shulman et Ieshko, 2003. Despite their similar spore morphology, they exhibit distinct host preferences, tissue affinities and geographical distributions. Chloromyxum schurovi predominantly infects the renal tubules of Salmo salar Linnaues and S. trutta Linnaeus in Europe, while C. majori targets the glomeruli of Oncorhynchus mykiss (Walbaum) and O. tshawytscha (Walbaum) in North America. The sequence data for C. majori and C. schurovi have been either missing or questionable. In our study, we examined the kidneys of two salmonid species for chloromyxid infections, using both morphological and molecular data to characterise Chloromyxum species in salmonids. The sequence of C. schurovi obtained in our study did not match the previously published parasite data. Instead, it clustered as an independent lineage sister to the Paramyxidium Freeman et Kristmundsson, 2018 clade gathering the species from various fish organs, including the urinary tract. Our findings clarified the taxonomic origin of the previous C. schurovi sequence as Myxidium giardi Cépède, 1906, highlighting the risks associated with the presence of myxozoan blood stages in the bloodstream of their fish host and the challenges of non-specific PCR amplification. We redescribe C. schurovi, thus contributing to a better understanding of the diversity and phylogeny of kidney-infecting species of Chloromyxum.
- MeSH
- fylogeneze * MeSH
- ledviny parazitologie MeSH
- Myxozoa * klasifikace genetika anatomie a histologie izolace a purifikace MeSH
- nemoci ryb * parazitologie MeSH
- parazitární nemoci u zvířat * parazitologie epidemiologie MeSH
- pstruh * parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
An increasing number of older patients with acute myeloid leukemia (AML) are offered an allogeneic hematopoietic stem cell transplantation (allo-HSCT). Normally, older patients have older matched related donors (MRD). Matched unrelated donors (MUD) are an important alternative, but it remains unclear whether a younger MUD is associated with better outcomes, especially in the context of post-transplant cyclophosphamide (PTCy). We compared outcomes of patients older than 50 years with AML in first complete remission (CR1) and receiving a first HSCT from a 10/10 MUD aged younger than 40 years to those receiving a graft from a MRD aged older than 50 years, using PTCy and with well-known transplant conditioning intensity (TCI) score. A total of 345 consecutive patients were included and classified according to TCI score as low, intermediate, or high. On multivariable analysis in the TCI-intermediate/high group, MUD was associated with better graft-versus-host disease-free, relapse-free survival, lower non-relapse mortality and lower relapse incidence. For patients receiving a TCI-low regimen, outcomes are independent on the type of donor. In patients with AML in CR1, older than 50 years and receiving a TCI-intermediate/high conditioning regimen using PTCy, a MUD younger than 40 years is preferable over a MRD older than 50 years.
- MeSH
- akutní myeloidní leukemie * terapie mortalita farmakoterapie patologie MeSH
- cyklofosfamid * terapeutické užití aplikace a dávkování MeSH
- dospělí MeSH
- homologní transplantace MeSH
- indukce remise * MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- nemoc štěpu proti hostiteli etiologie MeSH
- nepříbuzný dárce MeSH
- příprava pacienta k transplantaci * metody MeSH
- prognóza MeSH
- senioři MeSH
- transplantace hematopoetických kmenových buněk * metody MeSH
- věkové faktory MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
There is a paucity of information on how to select the most appropriate unrelated donor (UD) in hematopoietic stem cell transplantation (HSCT) using posttransplant cyclophosphamide (PTCy). We retrospectively analyzed the characteristics of 10/10 matched UDs (MUDs) and 9/10 mismatched UDs (MMUDs) that may affect transplant outcomes in patients with acute myeloid leukemia (AML) in first or second complete remission (CR1 or CR2). The primary end point was leukemia-free survival (LFS). Overall, 1011 patients were included with a median age of 54 years (range, 18-77). Donors had a median age of 29 years (range, 18-64); 304 (30%) were females, of which 150 (15% of the whole group) were donors to male recipients, and 621 (61%) were MUDs; 522 (52%) had negative cytomegalovirus (CMV-neg) serostatus, of which 189 (19%) were used for CMV-neg recipients. Donor age older than 30 years had a negative impact on relapse (hazard ratio [HR], 1.38; 95% confidence interval [CI], 1.06-1.8), LFS (HR, 1.4; 95% CI, 1.12-1.74), overall survival (HR 1.45; 95% CI, 1.14-1.85) and graft-versus-host disease (GVHD) free, relapse-free survival (HR, 1.29; 95% CI, 1.07-1.56). In addition, CMV-neg donors for CMV-neg recipients were associated with improved LFS (HR, 0.74; 95% CI, 0.55-0.99). The use of MMUD and female donors for male recipients did not significantly impact any transplant outcomes. For patients undergoing HSCT from a UD with PTCy for AML, donor age <30 years significantly improves survival. In this context, donor age might be prioritized over HLA match considerations. In addition, CMV-neg donors are preferable for CMV-neg recipients. However, further research is needed to validate and refine these recommendations.
- MeSH
- akutní myeloidní leukemie * terapie mortalita MeSH
- cyklofosfamid terapeutické užití MeSH
- dospělí MeSH
- HLA antigeny imunologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- nemoc štěpu proti hostiteli etiologie MeSH
- nepříbuzný dárce * MeSH
- přežití bez známek nemoci MeSH
- retrospektivní studie MeSH
- senioři MeSH
- testování histokompatibility MeSH
- transplantace hematopoetických kmenových buněk * MeSH
- věkové faktory MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Infekční choroby představují i ve 21. století závažný zdravotnický, sociální a ekonomický problém. V článku jsou diskutovány nové možnosti léčby virem HIV a virové hepatitidy D, narůstající výskyt virové hepatitidy E a alveolární echinokokózy v České republice. Ve všech případech se jedná o vysoce aktuální témata, které jsou významná v České republice i v mezinárodním měřítku. Dlouhodobě působící pomalu uvolňovaná antiretrovirová léčba (long-acting slow effective release antiretroviral therapy, LASER ART) představuje nejmodernější formu modifikace antiretrovirové léčby (ART). V České republice je k dispozici od února 2023. Podle klinických studií preferuje dlouhodobý léčebný režim 90–98 % pacientů. Bulevirtid (BLV) je syntetický lipopeptid, skládající se ze 47 aminokyselin z domény preS1 velkého proteinu HBsAg, který se váže na vspecifický receptor (sodium taurocholate cotransporting polypetide – NTCP) na povrchu jaterních buněk, a tím brání stupu HDV do hepatocytu. BLV je první schválený antivirový lék pro léčbu hepatitidy D u pacientů s kompenzovaným jaterním onemocněním. Počet hlášených případů akutní hepatitidy E v České republice byl v letech 2016–2021 většinou kolem 200–250 případů ročně. V roce 2022 došlo k nárůstu na 319 a v roce 2023 dokonce na 684 případů akutní hepatitidy E. Co je toho příčinou, není zatím definitivně určeno, ale je velmi pravděpodobné, že tento nárůst souvisí se zvýšenou prevalencí infekce HEV u rezervoárových zvířat. Alveolární echinokokózu způsobuje tasemnice Echinococcus multilocularis sensu lato. V Evropě jsou nejčastějším definitivním hostitelem lišky a mezihostitelem hlodavci (myši, hraboši atd.). K přenosu infekce dochází pozřením vajíček obsažených ve stolici definitivních hostitelů: lesní plody, houby, medvědí česnek a jiné potraviny kontaminované trusem nakažených lišek. Klinicky se onemocnění manifestuje jako invazivní jaterní proces podobný svým růstem a šířením malignímu nádoru, a to i možností metastatického šíření do jiných orgánů.
Infectious diseases are still a major health, social and economic problem in the 21st century. New treatment options for HIV and viral hepatitis D, the increasing incidence of viral hepatitis E and alveococcosis in the Czech Republic are discussed. In all cases, these are highly topical issues that are important in the Czech Republic and internationally. Long-acting slow effective release antiretroviral therapy (LASER ART) represents the most advanced form of modification of antiretroviral therapy (ART). It has been available in the Czech Republic since February 2023. According to clinical trials, 90-98 % of patients prefer a long-term regimen. Bulevirtide (BLV) is a synthetic lipopeptide, consisting of 47 amino acids from the preS1 domain of the large HBsAg protein, which binds to a specific receptor (sodium taurocholate cotransporting polypeptide - NTCP) on the surface of liver cells, thereby preventing HDV from entering the hepatocyte. BLV is the first approved antiviral drug for the treatment of hepatitis D in patients with compensated liver disease. The number of reported cases of acute hepatitis E in the Czech Republic from 2016-2021 was mostly around 200-250 cases per year. There will be an increase to 319 cases of acute hepatitis E in 2022 and even 684 cases in 2023. What is causing this is not yet definitively determined, but it is very likely that this increase is related to the increased prevalence of HEV infection in reservoir animals. Alveolar echinococcosis is caused by tapeworm Echinococcus multilocularis sensu lato. In Europe, foxes are the most common definitive host and rodents (mice, voles, etc.) are intermediate hosts. Transmission of infection occurs by ingestion of eggs contained in the faeces of definitive hosts: berries, mushrooms, wild garlic and other foods contaminated with the faeces of infected foxes. Clinically, the disease manifests itself as an invasive hepatic process similar in growth and spread to a malignant tumour, including the possibility of metastatic dissemination to other organs.
- MeSH
- antiretrovirové látky aplikace a dávkování MeSH
- Echinococcus multilocularis patogenita MeSH
- echinokokóza jater diagnóza etiologie přenos terapie MeSH
- hepatitida D farmakoterapie MeSH
- hepatitida E epidemiologie prevence a kontrola MeSH
- HIV infekce farmakoterapie terapie MeSH
- infekční lékařství * trendy MeSH
- kombinovaná farmakoterapie metody MeSH
- lidé MeSH
- transplantace MeSH
- virová hepatitida u lidí epidemiologie farmakoterapie MeSH
- virus hepatitidy E genetika patogenita MeSH
- Check Tag
- lidé MeSH
Influenza A viruses, causing seasonal epidemics and occasional pandemics, rely on interactions with host proteins for their RNA genome transcription and replication. The viral RNA polymerase utilizes host RNA polymerase II (Pol II) and interacts with the serine 5 phosphorylated (pS5) C-terminal domain (CTD) of Pol II to initiate transcription. Our study, using single-particle electron cryomicroscopy (cryo-EM), reveals the structure of the 1918 pandemic influenza A virus polymerase bound to a synthetic pS5 CTD peptide composed of four heptad repeats mimicking the 52 heptad repeat mammalian Pol II CTD. The structure shows that the CTD peptide binds at the C-terminal domain of the PA viral polymerase subunit (PA-C) and reveals a previously unobserved position of the 627 domain of the PB2 subunit near the CTD. We identify crucial residues of the CTD peptide that mediate interactions with positively charged cavities on PA-C, explaining the preference of the viral polymerase for pS5 CTD. Functional analysis of mutants targeting the CTD-binding site within PA-C reveals reduced transcriptional function or defects in replication, highlighting the multifunctional role of PA-C in viral RNA synthesis. Our study provides insights into the structural and functional aspects of the influenza virus polymerase-host Pol II interaction and identifies a target for antiviral development.IMPORTANCEUnderstanding the intricate interactions between influenza A viruses and host proteins is crucial for developing targeted antiviral strategies. This study employs advanced imaging techniques to uncover the structural nuances of the 1918 pandemic influenza A virus polymerase bound to a specific host protein, shedding light on the vital process of viral RNA synthesis. The study identifies key amino acid residues in the influenza polymerase involved in binding host polymerase II (Pol II) and highlights their role in both viral transcription and genome replication. These findings not only deepen our understanding of the influenza virus life cycle but also pinpoint a potential target for antiviral development. By elucidating the structural and functional aspects of the influenza virus polymerase-host Pol II interaction, this research provides a foundation for designing interventions to disrupt viral replication and transcription, offering promising avenues for future antiviral therapies.
- MeSH
- chřipka lidská virologie MeSH
- elektronová kryomikroskopie * MeSH
- fosforylace MeSH
- genetická transkripce MeSH
- lidé MeSH
- molekulární modely MeSH
- proteinové domény MeSH
- replikace viru MeSH
- RNA virová metabolismus genetika MeSH
- RNA-dependentní RNA-polymerasa * metabolismus chemie MeSH
- RNA-polymerasa II * metabolismus chemie MeSH
- vazba proteinů MeSH
- virové proteiny * metabolismus chemie genetika MeSH
- virus chřipky A * metabolismus genetika enzymologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The unicellular parasite Leishmania has a precisely defined cell architecture that is inherited by each subsequent generation, requiring a highly coordinated pattern of duplication and segregation of organelles and cytoskeletal structures. A framework of nuclear division and morphological changes is known from light microscopy, yet this has limited resolution and the intrinsic organisation of organelles within the cell body and their manner of duplication and inheritance is unknown. Using volume electron microscopy approaches, we have produced three-dimensional reconstructions of different promastigote cell cycle stages to give a spatial and quantitative overview of organelle positioning, division and inheritance. The first morphological indications seen in our dataset that a new cell cycle had begun were the assembly of a new flagellum, the duplication of the contractile vacuole and the increase in volume of the nucleus and kinetoplast. We showed that the progression of the cytokinesis furrow created a specific pattern of membrane indentations, while our analysis of sub-pellicular microtubule organisation indicated that there is likely a preferred site of new microtubule insertion. The daughter cells retained these indentations in their cell body for a period post-abscission. By comparing cultured and sand fly derived promastigotes, we found an increase in the number and overall volume of lipid droplets in the promastigotes from the sand fly, reflecting a change in their metabolism to ensure transmissibility to the mammalian host. Our insights into the cell cycle mechanics of Leishmania will support future molecular cell biology analyses of these parasites.
- MeSH
- buněčné dělení MeSH
- buněčný cyklus MeSH
- Leishmania mexicana * genetika MeSH
- Leishmania * MeSH
- paraziti * MeSH
- Psychodidae * parazitologie MeSH
- savci MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Rearing common bed bugs (Cimex lectularius L.) and other hematophagous insects is essential for basic, medical, and pest-control research. Logistically, acquiring fresh blood can be a challenge, while biologically, the eventual effects of different rearing and blood preparation protocols on bed bug genotype and phenotype pose a risk of biased research results. Using bed bug populations that are either bat- (BL) or human-related (HL), we tested the short- and long-term effects of rearing bugs on live bats or human volunteers, or artificially on CPDA (citrate phosphate dextrose, adenine)-treated blood, measuring meal size, body size, and fertility. We found that artificial feeding did not affect meal size compared with feeding on natural hosts. Long-term rearing across many generations of HL on CPDA-preserved blood led to reduced body size and fertility compared with populations reared on human volunteers. Blood preservatives increased the proportion of sterile eggs even after a single feed. Finally, our results indicated that laboratory reared bed bugs were smaller, regardless of the blood source, than wild bugs. Similar effects of artificial feeding or laboratory rearing alone should be considered in future studies using bed bug cultures to choose an appropriate rearing protocol. With regard to switching between bat and human hosts, HL took smaller meals and BL had lower fertility when fed on bats than when fed on humans. We attribute these results to methodological constrains, specifically the inconsistency of bat feeding, rather than to host specialization. Nevertheless, BL can be easily reared using human blood and artificial feeding systems.
- MeSH
- Chiroptera * MeSH
- fertilita MeSH
- Heteroptera * MeSH
- lidé MeSH
- štěnice * MeSH
- stravovací zvyklosti MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This paper represents the results of screening a diversity of fungal endophytes associated with Vitis vinifera leaves and canes in the Czech Republic. The characterization of strains is based on morphological and phylogenetic analyses of ITS, EF1α and TUB2 sequence data. Our strain selection covers 16 species and seven orders belonging to Ascomycota and Basidiomycota. Together with ubiquitous fungi, we report on several poorly known plant-associated fungi, Angustimassarina quercicola (= A. coryli, a synonym proposed in this study) and Pleurophoma pleurospora. Other species, such as Didymella negriana, D. variabilis, Neosetophoma sp. (species identical or sister to N. rosae), Phragmocamarosporium qujingensis and Sporocadus rosigena, have so far been little known and rarely found, but are frequent on V. vinifera in different parts of the world and obviously belong to a microbiota with a strong preference for this plant. Detailed taxonomical identification allowed us to identify species with apparent stable associations with V. vinifera, for which further interactions with V. vinifera can be expected. Our study is the first to focus on V. vinifera endophytes in Central Europe and expands the knowledge about their taxonomy, ecology and geography.
- MeSH
- Basidiomycota * MeSH
- endofyty genetika MeSH
- fylogeneze MeSH
- houby MeSH
- Vitis * mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH