The chicken caecum is colonised by hundreds of different bacterial species. Which of these are targeted by immunoglobulins and how immunoglobulin expression shapes chicken caecal microbiota has been addressed in this study. Using cell sorting followed by sequencing of V3/V4 variable region of 16S rRNA, bacterial species with increased or decreased immunoglobulin coating were determined. Next, we determined also caecal microbiota composition in immunoglobulin knockout chickens. We found that immunoglobulin coating was common and major taxa were coated with immunoglobulins. Similarly, more taxa required immunoglobulin production for caecum colonisation compared to those which became abundant in immunoglobulin-deficient chickens. Taxa with low immunoglobulin coating such as Lactobacillus, Blautia, [Eubacterium] hallii, Megamonas, Fusobacterium and Desulfovibrio all encode S-layer proteins which may reduce interactions with immunoglobulins. Although there were taxa which overgrew in Ig-deficient chickens (e.g. Akkermansia) indicating immunoglobulin production acted to exclude them from the chicken caecum, in most of the cases, immunoglobulin production more likely contributed to fixing the desired microbiota in the chicken caecum.
- MeSH
- Bacteria klasifikace genetika MeSH
- cékum * mikrobiologie MeSH
- imunoglobuliny * MeSH
- kur domácí * mikrobiologie imunologie MeSH
- RNA ribozomální 16S * genetika MeSH
- střevní mikroflóra * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- imunoglobuliny * MeSH
- RNA ribozomální 16S * MeSH
Lake Sinai virus (LSV) is one of over 20 honey bee viruses. Variants of LSV have been classified as members of two officially recognised species, Lake Sinai virus 1 and Lake Sinai virus 2. However, there are currently a limited number of whole-genome sequences, and the genetic variability of the virus indicates that additional species may need to be established. Extracted nucleic acid of 209 honey bee samples was screened by PCR for 11 honey bee viruses. LSV was the third most abundant virus (36.9% of positive samples), after Apis mellifera filamentous virus (72.2%) and deformed wing virus (52.5%). LSV-positive samples were analyzed further by PCR with primers targeting the region encoding the viral RNA-dependent RNA polymerase. Subsequently, the PCR products were sequenced, and the resulting sequences were used for a first round of phylogenetic analysis. Based on those results, several isolates were selected for whole-genome sequencing, and the complete genome sequences were used for additional phylogenetic analysis. The results indicated the presence of at least three genetically distinct groups of LSV in the Czech Republic, the most prevalent one being related to LSV 2 but too dissimilar to be considered a member of the same species. Two sequences of a major LSV strain cluster native to the Czech Republic were determined, representing the first Czech LSV strains published to date.
- MeSH
- fylogeneze MeSH
- nukleové kyseliny * MeSH
- RNA-dependentní RNA-polymerasa MeSH
- RNA-viry * genetika MeSH
- včely MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
- Názvy látek
- nukleové kyseliny * MeSH
- RNA-dependentní RNA-polymerasa MeSH
Listeria monocytogenes (Lm) is a ubiquitous bacterium that causes listeriosis, a serious foodborne illness. In the nature-to-human transmission route, Lm can prosper in various ecological niches. Soil and decaying organic matter are its primary reservoirs. Certain clonal complexes (CCs) are over-represented in food production and represent a challenge to food safety. To gain new understanding of Lm adaptation mechanisms in food, the genetic background of strains found in animals and environment should be investigated in comparison to that of food strains. Twenty-one partners, including food, environment, veterinary and public health laboratories, constructed a dataset of 1484 genomes originating from Lm strains collected in 19 European countries. This dataset encompasses a large number of CCs occurring worldwide, covers many diverse habitats and is balanced between ecological compartments and geographic regions. The dataset presented here will contribute to improve our understanding of Lm ecology and should aid in the surveillance of Lm. This dataset provides a basis for the discovery of the genetic traits underlying Lm adaptation to different ecological niches.
New analytical techniques that overcome major drawbacks of current routinely used viral infection diagnosis methods, i.e., the long analysis time and laboriousness of real-time reverse-transcription polymerase chain reaction (qRT-PCR) and the insufficient sensitivity of "antigen tests", are urgently needed in the context of SARS-CoV-2 and other highly contagious viruses. Here, we report on an antifouling terpolymer-brush biointerface that enables the rapid and sensitive detection of SARS-CoV-2 in untreated clinical samples. The developed biointerface carries a tailored composition of zwitterionic and non-ionic moieties and allows for the significant improvement of antifouling capabilities when postmodified with biorecognition elements and exposed to complex media. When deployed on a surface of piezoelectric sensor and postmodified with human-cell-expressed antibodies specific to the nucleocapsid (N) protein of SARS-CoV-2, it made possible the quantitative analysis of untreated samples by a direct detection assay format without the need of additional amplification steps. Natively occurring N-protein-vRNA complexes, usually disrupted during the sample pre-treatment steps, were detected in the untreated clinical samples. This biosensor design improved the bioassay sensitivity to a clinically relevant limit of detection of 1.3 × 104 PFU/mL within a detection time of only 20 min. The high specificity toward N-protein-vRNA complexes was validated both by mass spectrometry and qRT-PCR. The performance characteristics were confirmed by qRT-PCR through a comparative study using a set of clinical nasopharyngeal swab samples. We further demonstrate the extraordinary fouling resistance of this biointerface through exposure to other commonly used crude biological samples (including blood plasma, oropharyngeal, stool, and nasopharyngeal swabs), measured via both the surface plasmon resonance and piezoelectric measurements, which highlights the potential to serve as a generic platform for a wide range of biosensing applications.
- Klíčová slova
- SARS-CoV-2, functional coatings, piezoelectric biosensor, polymer brush, rapid detection, zwitterionic materials,
- MeSH
- biosenzitivní techniky MeSH
- biotest MeSH
- bioznečištění MeSH
- COVID-19 diagnóza MeSH
- fosfoproteiny chemie MeSH
- hmotnostní spektrometrie MeSH
- ionty MeSH
- koronavirové nukleokapsidové proteiny chemie MeSH
- lidé MeSH
- limita detekce MeSH
- nazofarynx virologie MeSH
- nosní sliznice virologie MeSH
- odběr biologického vzorku MeSH
- polymerázová řetězová reakce s reverzní transkripcí MeSH
- polymery chemie MeSH
- reprodukovatelnost výsledků MeSH
- RNA virová metabolismus MeSH
- SARS-CoV-2 * MeSH
- senzitivita a specificita MeSH
- testování na COVID-19 * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- fosfoproteiny MeSH
- ionty MeSH
- koronavirové nukleokapsidové proteiny MeSH
- nucleocapsid phosphoprotein, SARS-CoV-2 MeSH Prohlížeč
- polymery MeSH
- RNA virová MeSH
A total of 152 aerosol and spider web samples were collected: 96 spider's webs in karst areas in 4 European countries (Czech Republic, France, Italy, and Slovakia), specifically from the surface environment (n = 44), photic zones of caves (n = 26), and inside (aphotic zones) of caves (n = 26), 56 Particulate Matter (PM) samples from the Sloupsko-Sosuvsky Cave System (speleotherapy facility; n = 21) and from aerosol collected from the nearby city of Brno (n = 35) in the Czech Republic. Nontuberculous mycobacteria (NTM) were isolated from 13 (13.5%) spider's webs: 5 isolates of saprophytic NTM (Mycobacterium gordonae, M. kumamotonense, M. terrae, and M. terrae complex) and 6 isolates of potentially pathogenic NTM (M. avium ssp. hominissuis, M. fortuitum, M. intracellulare, M. peregrinum and M. triplex). NTM were not isolated from PM collected from cave with the speleotherapy facility although mycobacterial DNA was detected in 8 (14.3%) samples. Temperature (8.2 °C, range 8.0-8.4 °C) and relative humidity (94.7%, range 93.6-96.6%) of air in this cave were relatively constant. The average PM2.5 and PM10 mass concentration was 5.49 µg m-3 and 11.1 µg m-3. Analysed anions (i.e., F-, Cl-, NO2-, SO42-, PO43- and NO3-) originating largely from the burning of wood and coal for residential heating in nearby villages in the surrounding area. The air in the caves with speleotherapy facilities should be monitored with respect to NTM, PM and anions to ensure a safe environment.
Sex chromatin is a conspicuous body that occurs in polyploid nuclei of most lepidopteran females and consists of numerous copies of the W sex chromosome. It is also a cytogenetic tool used to rapidly assess the W chromosome presence in Lepidoptera. However, certain chromosomal features could disrupt the formation of sex chromatin and lead to the false conclusion that the W chromosome is absent in the respective species. Here we tested the sex chromatin presence in 50 species of Geometridae. In eight selected species with either missing, atypical, or normal sex chromatin patterns, we performed a detailed karyotype analysis by means of comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). The results showed a high diversity of W chromosomes and clarified the reasons for atypical sex chromatin, including the absence or poor differentiation of W, rearrangements leading to the neo-W emergence, possible association with the nucleolus, and the existence of multiple W chromosomes. In two species, we detected intraspecific variability in the sex chromatin status and sex chromosome constitution. We show that the sex chromatin is not a sufficient marker of the W chromosome presence, but it may be an excellent tool to pinpoint species with atypical sex chromosomes.
- Klíčová slova
- Geometridae, Lepidoptera, W chromosome, comparative genomic hybridization, intraspecific chromosomal variability, neo-sex chromosomes, sex chromatin, sex chromosome evolution,
- MeSH
- druhová specificita MeSH
- hybridizace in situ fluorescenční MeSH
- karyotyp MeSH
- můry genetika MeSH
- pohlavní chromozomy genetika MeSH
- sexchromatin metabolismus MeSH
- srovnávací genomová hybridizace MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In this study, we addressed the origin of chicken gut microbiota in commercial production by a comparison of eggshell and feed microbiota with caecal microbiota of 7-day-old chickens, using microbiota analysis by 16S rRNA sequencing. In addition, we tested at which timepoint during prenatal or neonatal development it is possible to successfully administer probiotics. We found that eggshell microbiota was a combination of environmental and adult hen gut microbiota but was completely different from caecal microbiota of 7-day-old chicks. Similarly, we observed that the composition of feed microbiota was different from caecal microbiota. Neither eggshell nor feed acted as an important source of gut microbiota for the chickens in commercial production. Following the experimental administration of potential probiotics, we found that chickens can be colonised only when already hatched and active. Spraying of eggs with gut anaerobes during egg incubation or hatching itself did not result in effective chicken colonisation. Such conclusions should be considered when selecting and administering probiotics to chickens in hatcheries. Eggshells, feed or drinking water do not act as major sources of gut microbiota. Newly hatched chickens must be colonised from additional sources, such as air dust with spores of Clostridiales. The natural colonisation starts only when chickens are already hatched, as spraying of eggs or even chickens at the very beginning of the hatching process did not result in efficient colonisation.
- Klíčová slova
- caecum, chicken, eggshell, feed, hatchery, microbiota,
- Publikační typ
- časopisecké články MeSH
AIMS: Granulation tissue (GT) and specialized pro‑resolving mediators such as lipoxins and resolvins are key elements in the successful resolution of periodontitis. Aspirin‑triggered lipoxins and resolvins are even more powerful than their natural analogues. Their biosynthesis can be accelerated by omega-3 fatty acids. The aim of this study was to evaluate the use of GT enriched by aspirin and omega-3 fatty acids during the surgical treatment of periodontitis in an experimental animal model (rabbit). METHODS: In each of 24 rabbits, two experimental periodontal defects were created. In total, 47 defects were treated with open-flap debridement and one of three procedures: (1) GT extracted and soaked with aspirin and omega-3 fatty acids (ASA+OMEGA3 group); (2) GT soaked with saline (PLACEBO group); or (3) GT left untreated (CONTROL group). Then, the GT was replaced in situ. Primary evaluated criteria were the probing pocket depth (PPD) and the clinical attachment level (CAL). Necropsies were harvested 2, 6, and 12 weeks after surgery. The samples were used for histological and molecular biological assessment. RESULTS: A trend of greater PPD and CAL in the ASA+OMEGA3 group was observed at 6 weeks. However, there was no significant difference between them. During the observation period, tissue levels of FGF-7, IL-1β and TIMP-1 showed a statistically significant decrease (P<0.05). For the other variables, the ASA+OMEGA3 group was comparable with the PLACEBO and CONTROL groups. CONCLUSION: This experiment did not demonstrate the superiority of the proposed approach. However, the enriched granulation tissue did not impair healing outcomes.
- Klíčová slova
- granulation tissue, inflammation mediators, lipoxin, oral surgery, periodontitis,
- MeSH
- Aspirin farmakologie MeSH
- granulační tkáň MeSH
- králíci MeSH
- kyseliny mastné omega-3 * farmakologie MeSH
- lipoxiny * MeSH
- parodontitida * farmakoterapie MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- Aspirin MeSH
- kyseliny mastné omega-3 * MeSH
- lipoxiny * MeSH
Porcine circovirus causes the post-weaning multi-systemic wasting syndrome. Despite the existence of commercial vaccines, the development of more effective and cheaper vaccines is expected. The usage of chimeric antigens allows serological differentiation between naturally infected and vaccinated animals. In this work, recombinant pentameric vaccination protein particles spontaneously assembled from identical subunits-chimeric fusion proteins derived from circovirus capsid antigen Cap and a multimerizing subunit of mouse polyomavirus capsid protein VP1 were purified and characterized using asymmetric flow field-flow fractionation (AF4) coupled with UV and MALS/DLS (multi-angle light scattering/dynamic light scattering) detectors. Various elution profiles were tested, including constant cross-flow and decreasing cross-flow (linearly and exponentially). The optimal sample retention, separation efficiency, and resolution were assessed by the comparison of the hydrodynamic radius (Rh) measured by online DLS with the Rh values calculated from the simplified retention equation according to the AF4 theory. The results show that the use of the combined elution profiles (exponential and constant cross-flow rates) reduces the time of the separation, prevents undesirable sample-membrane interaction, and yields better resolution. Besides, the results show no self-associations of the individual pentameric particles into larger clusters and no sample degradation during the AF4 separation. The Rg/Rh ratios for different fractions are in good correlation with morphological analyses performed by transmission electron microscopy (TEM). Additionally to the online analysis, the individual fractions were subjected to offline analysis, including batch DLS, TEM, and SDS-PAGE, followed by Western blot.
- Klíčová slova
- Asymmetric flow field-flow fractionation (AF4), Circovirus, Recombinant antigen,
- MeSH
- buněčné linie MeSH
- Circovirus chemie MeSH
- frakcionace tokem v poli přístrojové vybavení metody MeSH
- multimerizace proteinu MeSH
- myši MeSH
- rekombinantní fúzní proteiny analýza izolace a purifikace MeSH
- Theilovirus chemie MeSH
- virové proteiny analýza izolace a purifikace MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- rekombinantní fúzní proteiny MeSH
- virové proteiny MeSH
We present epidemiological, clinical and laboratory findings of five Czech patients diagnosed with autochthonous mosquito-borne disease-four patients with confirmed West Nile virus (WNV) and one patient with Usutu virus (USUV) infections, from July to October 2018, including one fatal case due to WNV. This is the first documented human outbreak caused by WNV lineage 2 in the Czech Republic and the first record of a neuroinvasive human disease caused by USUV, which illustrates the simultaneous circulation of WNV and USUV in the country.
- Klíčová slova
- Usutu virus, West Nile virus, human, mosquito-borne infections,
- Publikační typ
- časopisecké články MeSH
