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1. Erysipelas in geese and ducks is an infectious disease causing considerable economic losses in the poultry sector in Poland. The aim of this study was to determine the distribution of erysipelas cases in age groups of geese and in periods of the calendar year and to assess macroscopic lesions in birds infected with Erysipelothrix rhusiopathiae. 2. The study used 286 geese and 16 ducks delivered to the laboratory for diagnosis in the years 2019–2021. The birds came from 99 different farms. E. rhusiopathiae from clinical samples were cultured on Columbia blood agar and identified by real-time PCR. Pathological lesions were characterised during anatomopathological examination. 3. Distribution of erysipelas cases in age groups of geese and periods of the calendar year differed significantly from the assumed even distribution. Most cases were noted in August and September in birds aged between 11 and 13 weeks. Necropsy of birds infected with E. rhusiopathiae showed anatomopathological lesions characteristic of generalised infection, affecting multiple organs. 4. The uneven distribution of erysipelas cases in geese in different age groups and periods of the calendar year suggested that both the age of the birds and climatic conditions are predisposing factors for infection. [ABSTRACT FROM AUTHOR]

Salmonella diarizonae (IIIb) is frequently isolated from reptiles and less frequently from birds and mammals. However, its isolation from invasive human infections has not been widely reported. Migratory mallard ducks are excellent bioindicators of pathogen presence and pathogen antibiotic resistance (AMR). We present the first isolation from a mallard duck in central Europe of the antibiotic-resistant Salmonella enterica subsp. diarizonae with the unique antigenic pattern 58:r:z 53 and report its whole-genome sequencing, serosequencing, and genotyping, which enabled the prediction of its pathogenicity and comparison with phenotypic AMR. The isolated strain was highly similar to S. diarizonae isolated from humans and food. Twenty-four AMR genes were detected, including those encoding aminoglycoside, fluoroquinolone, macrolide, carbapenem, tetracycline, cephalosporin, nitroimidazole, peptide antibiotic, and disinfecting agent/antiseptic resistance. Six Salmonella pathogenicity islands were found (SPI-1, SPI-2, SPI-3, SPI-5, SPI-9, and SPI-13). An iron transport system was detected in SPI-1 centisome C63PI. Plasmid profile analyses showed three to be present. Sequence mutations in the invA and invF genes were noted, which truncated and elongated the proteins, respectively. The strain also harbored genes encoding type-III secretion-system effector proteins and many virulence factors found in S. diarizonae associated with human infections. This study aims to elucidate the AMR and virulence genes in S. enterica subsp. diarizonae that may most seriously threaten human health.

Enterococcus spp. are normal intestinal tract microflorae found in poultry. However, the last decades have shown that several species, e.g., Enterococcus cecorum , have become emerging pathogens in broilers and may cause numerous losses in flocks. In this study, two combinations (H1 and H2) of menthol, 1,8-cineol, linalool, methyl salicylate, γ-terpinene, p-cymene, trans -anethole, terpinen-4-ol and thymol were used in an in vitro model, analyzing its effectiveness against the strains E. cecorum , E. faecalis , E. faecium , E. hirae and E. gallinarum isolated from broiler chickens from industrial farms. To identify the isolated strains classical microbiological methods and VITEK 2 GP cards were used. Moreover for E. cecorum a PCR test was used.. Antibiotic sensitivity (MIC) tests were performed for all the strains. For the composition H1, the effective dilution for E. cecorum and E. hirae strains was 1:512, and for E. faecalis , E. faecium and E. gallinarum , 1:1024. The second mixture (H2) showed very similar results with an effectiveness at 1:512 for E. cecorum and E. hirae and 1:1024 for E. faecalis , E. faecium and E. gallinarum . The presented results suggest that the proposed composition is effective against selected strains of Enterococcus in an in vitro model, and its effect is comparable to classical antibiotics used to treat this pathogen in poultry. This may suggest that this product may also be effective in vivo and provide effective support in the management of enterococcosis in broiler chickens.

Introduction: Universally, in microbiological diagnostics the detection of live bacteria is essential. Rapid identification of pathogens enables appropriate remedial measures to be taken. The identification of many bacteria simultaneously facilitates the determination of the characteristics of the accompanying microbiota and/or the microbiological complexity of a given environment., Material and Methods: The effectiveness of the VITEK2 Compact automated microbial identification system and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS), analytical profile index (API) and Remel RapID tests were compared in identification of bacteria isolated from the alpaca gastrointestinal tract., Results: Most isolates were Gram-positive, such as Bacillus cereus, Bacillus flexus, Bacillus licheniformis, Bacillus pumilus and Bacillus subtilis; Enterococcus faecium, Enterococcus gallinarum, Enterococcus hirae and Enterococcus casseliflavus; Staphylococcus aureus, Staphylococcus equorum , Staphylococcus lentus , Staphylococcus pseudintermedius and Staphylococcus sciuri ; Paenibacillus amylolyticus ; Cellulosimicrobium cellulans ; Leuconostoc mesenteroides ; Clostridium perfringens ; Corynebacterium stationis , Corynebacterium xerosis , and Corynebacterium diphtheriae (the last only isolated manually by API Coryne and the VITEK2 system and Corynebacteria (CBC) card). Corynebacterium diphtheriae was misidentified by MALDI-TOF MS as Candida lipolytica (currently Yarrowia lipolytica ). Gram-positive and Gram-variable Micrococcus luteus were also isolated. Gram-negative Enterobacter cloacae , Enterobacter gergoviae , Enterobacter hormaechei and Enterobacter ludwigii ; E. coli ; Klebsiella pneumoniae subsp. pneumoniae ; Citrobacter braakii and Citrobacter freundii ; Serratia liquefaciens , Serratia odorifera and Serratia marcescens ; Morganella morganii subsp. morganii ; Providencia alcalifaciens ; Pseudomonas aeruginosa ; Stenotrophomonas maltophilia ; Moraxella osloensis ; and Ochrobactrum intermedium were also found. The yeasts Candida albicans, Candida haemulonii and Candida ciferrii were also present., Conclusion: MALDI-TOF MS enabled the identification of pathogens and opportunistic pathogens from the alpaca gut which may represent a high risk to human and animal health., Competing Interests: Conflict of Interests Statement: The authors declare that there is no conflict of interests regarding the publication of this article., (© 2023 Joanna Pławińska-Czarnak et al., published by Sciendo.)

Salmonella is a common foodborne infection. Many serovars belonging to Salmonella enterica subsp. enterica are present in the gut of various animal species. They can cause infection in human infants via breast milk or cross-contamination with powdered milk. In the present study, Salmonella BO was isolated from human milk in accordance with ISO 6579-1:2017 standards and sequenced using whole-genome sequencing (WGS), followed by serosequencing and genotyping. The results also allowed its pathogenicity to be predicted. The WGS results were compared with the bacterial phenotype. The isolated strain was found to be Salmonella enterica subsp. enterica serovar Typhimurium 4:i:1,2_69M ( S. Typhimurium 69M); it showed a very close similarity to S. enterica subsp. enterica serovar Typhimurium LT2. Bioinformatics sequence analysis detected eleven SPIs (SPI-1, SPI-2, SPI-3, SPI-4, SPI-5, SPI-9, SPI-12, SPI-13, SPI-14, C63PI, CS54_island). Significant changes in gene sequences were noted, causing frameshift mutations in yeiG , rfbP , fumA , yeaL , ybeU (insertion) and lpfD , avrA , ratB , yacH (deletion). The sequences of several proteins were significantly different from those coded in the reference genome; their three-dimensional structure was predicted and compared with reference proteins. Our findings indicate the presence of a number of antimicrobial resistance genes that do not directly imply an antibiotic resistance phenotype., Competing Interests: The authors declare no conflict of interest.

Escherichia coli infections (including APEC) in broiler chickens are not only a health and economic problem of the flock, but also a significant health threat to poultry meat consumers. The prophylactic and therapeutic effects of the phytobiotic composition on E. coli in broiler chickens were previously described. However, most of the data were related to the reference strains (for both in vitro and in vivo models). Based on the previous studies in human and animals, E. coli strains seem to be multidrug resistance. This, in turn, makes it necessary to develop effective alternative methods of treating this type of infection already at the stage of poultry production. In the present study, the antibacterial activity against various strains of E. coli (including APEC) was assessed for two innovative phytobiotics mixtures: H1, containing thymol, menthol, linalool, trans -anethole, methyl salicylate, 1,8-cineol, and p -cymene; H2, in addition to compounds from H1, containing terpinen-4-ol and γ-terpinene. The unique mixtures of phytobiotics used in the experiment were effective against various strains of E. coli , also against APEC, isolated from broiler chickens from traditional industrial breeding, as well as against those showing colistin resistance. The minimum inhibitory concentration (MIC) values for these unique mixtures were: For H1 1:512 for APEC and non-APEC E. coli strains isolated from day old chicks (DOCs), 1:512 for non-APEC, and 1:1024 for non-APEC isolated from broilers sample. For mixture H2, MIC for APEC from both type of samples (DOCs and broilers) was 1:1024 and for non-APEC (DOCs and broilers) was 1:512. The results suggest that phytobiotic compositions used in this study can be successfully used as a natural alternative to antibiotics in the treatment of E. coli infections in broiler chickens. The promising results may be a crucial point for further analyses in broiler flocks exposed to E. coli infections and where it is necessary to reduce the level of antibiotics or completely eliminate them, thus reducing the risk of foodborne infections.

Global pressure from consumers to improve animal welfare, and reduce microbiological risks or the use of antibiotics pose new challenges for the meat industry. Today's livestock production, despite many undertaken measures, is still far from being sustainable. This forced the need to work on alternative protein types that come from plants, insects, fungi, or cell culture processes. Due to some technical and legal barriers, cultivated meat is not present on the European market, however, in 2020 it was approved in Singapore and in 2022 in the USA. While the technology of obtaining cell cultures from animal muscles has been known and successfully practiced for years, the production of a stable piece of meat with appropriate texture, taste, and smell, is still a problem for several scientific groups related to subsequent companies trying to obtain the highest quality product, in line with the expectations of customers. Although the work on optimal cell meat production has been going on for years, it is still in an early stage, mainly due to several limitations that represent milestones for industrial production. The most important are: the culture media (without animal serum), which will provide an environment for optimal muscle development, natural or close to natural (but still safe for the consumer) stable scaffolds for growing cells. Here, we review the actual knowledge about the above-mentioned challenges which make the production of cellular meat not yet developed on an industrial scale.

Salmonella spp. is the most frequent cause of foodborne diseases, and the increasing occurrence of MDR strains is an additional and increasing problem. We collected Salmonella spp. strains isolated from meat (poultry and pork) and analysed their antibiotic susceptibility profiles and the occurrence of resistance genes. To determine the susceptibility profiles and identify MDR strains, we used two MIC methods (MICRONAUT and VITEC2 Compact) and 25 antibiotics. Phenotypic tests showed that 53.84% strains were MDR. Finally, molecular analysis strains revealed the presence of bla SHV , bla PSE-1 , bla TEM , but not bla CTX-M genes. Moreover, several genes were associated with resistance to aminoglycosides, cephalosporins, fluorochinolones, sulfonamides, and tetracyclines. This suggests that further research on the prevalence of antibiotic resistance genes (ARGs) in foodborne strains is needed, especially from a One Health perspective.

Background: The identification of natural antibacterial agents from various sources that can act effectively against disease-causing foodborne bacteria is one of the major concerns throughout the world. In the present study, a unique phytobiotics mixture containing thymol, menthol, linalool, trans -anethole, methyl salicylate, 1,8-cineole, and p -cymene was evaluated for antibacterial activity against selected strains of Salmonella spp., Results: The phytobiotics mixture was effective against Salmonella enterica subsp. enterica serovars Enteritidis, Typhimurium, and Kentucky. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of this unique mixture for these three pathogens were 1:256. Among these three strains, one S . Kentucky presented the most extensive resistance profiles to 18 antibiotics belonging to 5 classes of antibiotics. One of S. Typhimurium presents extensive resistance profiles to 14 antibiotics belonging to 5 classes of antibiotics., Conclusions: The results suggest that the phytobiotics mixture used in the experiment can be used as a strong natural antibacterial agent against Gram-negative foodborne pathogens such as S. Typhimurium, S. Kentucky, and S. Enteritidis. This is a preliminary analysis of the effectiveness of a phytobiotic product in an in vitro model, which may be the starting point for further studies, including in vivo animal models.

The "One Health" approach increasingly demonstrates the global spread of pathogenic microorganisms and their antimicrobial resistance in the environment, both in animals and humans. Salmonella enterica subsp. diarizonae is nowadays very often isolated from cold-blooded reptiles to a lesser extent from sheep, but unfortunately more and more often from humans. However, there are a few studies describing the isolation of Salmonella enterica subsp. diarizonae from migratory wild birds. The mallard duck ( Anas platyrhynchos ), a wild animal that traverses the continent of Eurasia, can be an excellent indicator of the spread of intestinal microbes as well as their resistance to antibiotics. This is the first report of the Salmonella enterica subsp. diarizonae detection in Poland in a migrating mallard duck. This research presented the identification difficulties associated with the isolation of Salmonella enterica subsp. diarizonae using three different biochemical tests and advanced serology tests. At the same time, we detected very high antimicrobial resistance in the isolated strain. By using the minimum inhibitory concentration (MIC) method, it was found that the isolated strain of S. enterica subsp. diarizonae has high antibiotic resistance against 14 of the 33 tested antimicrobials agents. The resistance genes that have been identified in S. enterica subsp. diarizonae include aadA , strA/strB , and bla TEM .

Background: Globally, Salmonella enterica is one of the leading causes of foodborne illness in humans. Food of animal origin is obligatorily tested for the presence of this pathogen. Unfortunately, in meat and meat products, this is often hampered by the presence of background microbiota, which may present as false-positive Salmonella ., Methods: For the identification of Salmonella spp. from meat samples of beef, pork, and poultry, the authorized detection method is PN-EN ISO 6579-1:2017-04 with the White-Kauffmann-Le Minor scheme, two biochemical tests: API 20E and VITEK II, and a real-time PCR-based technique., Results: Out of 42 presumptive strains of Salmonella , 83.3% Salmonella enterica spp. enterica , 14.3% Citrobacter braakii , and 12.4% Proteus mirabilis were detected from 180 meat samples., Conclusions: Presumptive strains of Salmonella should be identified based on genotypic properties such as DNA-based methods. The aim of this study was the isolation and identification of Salmonella spp. from miscellaneous meat sorts: beef, pork, and poultry.

Non-melanoma skin cancers (NMSCs), including basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), are the most frequently diagnosed cancers in humans, however, their exact pathogenesis is not fully understood. In recent years, it has been hypothesized that the recently discovered Hippo pathway could play a detrimental role in cutaneous carcinogenesis, but no direct connections have been made. The Hippo pathway and its effector, YAP, are responsible for tissue growth by accelerating cell proliferation, however, YAP upregulation and overexpression have also been reported in numerous types of tumors. There is also evidence that disrupted YAP/Hippo signaling is responsible for cancer growth, invasion, and metastasis. In this short review, we will explore whether the Hippo pathway is an important regulator of skin carcinogenesis and if it could be a promising target for future therapies.

1,25-dihydroxyvitamin-D 3 plays a central role in the immune system via binding to the vitamin D receptor. VDR polymorphisms have been associated with multiple autoimmune disorders, including psoriasis. Until now, five VDR polymorphisms, FokI , ApaI , BsmI , TaqI and TaaI /Cdx2, have been studied in psoriasis, with contradicting results. Therefore, this study aimed to evaluate the association of VDR polymorphisms with susceptibility to psoriasis, effectiveness of NB-UVB phototherapy and concentration of proinflammatory cytokines and vitamin D amongst the Polish population. VDR polymorphisms were analyzed by PCR-RFLP or real-time PCR. We found that the frequency of the TaaI /Cdx-2 GG genotype was significantly higher in psoriasis patients and was associated with regulation of IL-17 and IL-23 concentration. Moreover, TaaI /Cdx-2 AA might have a significant effect on the response to phototherapy amongst patients with psoriasis. Our results suggest that VDR is a susceptibility factor for psoriasis development. Moreover, TaaI /Cdx-2 variants have a significant effect on the response to phototherapy amongst patients with psoriasis and regulation of inflammatory response via decrease of IL-17 and IL-23 level after UVB phototherapy in the Polish population. Results of our study provide some evidence in support of the hypothesis that the vitamin D signaling pathway may be of relevance for pathogenesis and treatment of psoriasis.

Inflammasomes are key innate immune system receptors that detect pathogenic endo- and exogenous stressors like microorganisms or ultraviolet radiation (UVR) which activate the highly proinflammatory cytokines interleukin-1β and interleukin-18. Inflammasomes are not only involved in inflammation, but also in carcinogenesis and tumor progression. Due to the dynamic increase in non-melanoma skin cancers (NMSC), it has become necessary to determine how UVR, which plays a key role in NMSC development, can regulate the structure and function of inflammasomes. In the present study, the regulatory mechanisms of NOD-Like Receptor Family Pyrin Domain Containing 1 and 3 inflammasome activation as well as an effective inflammasome-mediated immune response after UVR exposition are discussed. The differences and similarities between these molecular complexes that monitor cellular health, inflammation, and skin carcinogenesis are also highlighted. Despite numerous scientific data, more studies are still required to better understand the biology of inflammasomes in skin cancer development and to explore their therapeutic potential., (Copyright: © Ciążyńska et al.)

Basal cell carcinoma (BCC) is the most common skin malignancy type in the Caucasian population, with a continuously increasing incidence rate. The etiology of BCC remains unknown, but it appears to have a multifactorial origin resulting from intrinsic and extrinsic factors, including short-wavelength ultraviolet B radiation. The role of specific proteins in BCC that are known to be responsible for the regulation of cell division and are involved in skin aging, including transforming growth factor (TGF)-β, Smad2, matrix metalloproteinases (MMPs)-1, -3, -8 and -9, cathepsin-K and progerin, remains unknown. The aim of the present study was to assess the mRNA and protein expression profile of samples with diagnosed nodular BCC (nBCC) compared with that of healthy skin samples collected from matched areas. The study group included 22 patients (10 men and 12 women; mean age, 59 years; range, 44-82 years) with pathologically confirmed nBCC, and 22 healthy volunteers (10 men and 12 women; mean age, 59 years; range, 43-78 years) as a control group. The expression of the studied proteins was assessed in all samples by western blotting and reverse transcription-quantitative polymerase chain reaction analysis. Statistically significant increases in the expression of TGF-β, Smad2, cathepsin-K, progerin and MMP-1, -3, -8 and -9 were detected in skin biopsies with diagnosed nBCC compared with the control group, confirming the important role of these proteins in skin carcinogenesis.

Ultraviolet radiation (UVR) is one of the most important environmental factors involved in photoaging. Exposure to UVR leads to dysregulation of expression of cell cycle-related proteins which play key role in skin photodegradation that pretends to develop carcinogenesis. This study examines the role of various UVB doses on the expression of transforming growth factor beta (TGF-β), Smad2, cathepsin K, progerin and matrix metalloproteinases (MMPs)-1,-3,-8,-9. A group consisting of 63 healthy individuals underwent one of the following treatments: (1) whole body exposed to UVB irradiation on each of 10 consecutive days with 0.7 MED, or (2) whole-body irradiation as described followed by a single erythemal UVB dose on a small body area, or (3) irradiated only with a single erythemal UVB dose on small body area, or (4) were not irradiated at all (control group). When we compared all irradiated groups to the control group, there was significantly higher expression of TGF-β, MMP-1,-3,-9 and cathepsin K proteins evaluated by Western blot method. The results suggest the role of UVB in impairment of proteins expression that is involved in cell cycle's regulation. Changes in the protein expression involved by acute and chronic UVR confirm its essential role in skin photodestruction. Moreover, obtained result indicates the tendency to occurrence of photoadaptation phenomenon., (© 2017 The American Society of Photobiology.)

The effects of LTs are mediated by GPCRs: cysLTs interact with CYSLTR1, CYSLTR2, or GPR17, and LTB 4 acts via BLT1R or BLT2R. Data relating to the presence of these receptors in mature tissue mast cells are not entirely known. By confocal microscopy with image analyses and flow cytometry, we established that native rat mast cells isolated from peritoneal cavity constitutively express all studied receptors. Moreover, we clearly documented that LTs by themselves can influence their own receptor expression. Low concentrations of LTs induce translocation of LT receptors from cell interior to plasma membrane, which can lead to increased mast cell responsiveness to LT stimulation. High concentrations of LTs cause internalization and, in consequence, reduction in the number of receptors on the cell surface, and it may result in desensitization of mast cells to subsequent LT stimulation. These observations may imply a physiological feedback mechanism regulating mast cell sensitivity to LT activation within tissues., (Copyright © 2017. Published by Elsevier Inc.)

Within the last decade, several antimicrobial peptides (AMPs) have been discovered. Cathelicidins are one family of AMPs characterized by a conserved cathelin domain and a variable C-terminal cationic antimicrobial domain. These peptides are produced by different cells, including leukocytes, epithelial cells and keratinocytes. Besides their direct antimicrobial function, cathelicidins can also regulate the course of inflammation and influence the mechanisms of innate immunity. In this review we discuss the biology of animal cathelicidins, their structure, expression and function.

Study Aim: Evaluation of detection and drug resistance of Mycobacterium tuberculosis in patients from the Łódzkie Voivodship in the period 2009 - 2013., Material and Methods: The data presented in the study include information obtained while diagnosing patients from the Łódzkie Voivodship in order to detect infections with Mycobacterium tuberculosis in the period 2009-2013., Results: In 2009-2013 we analyzed clinical specimens for the purpose of detection of Mycobacterium tuberculosis. Tubercle bacilli were confirmed in 5621 specimens in 2196 patients; positive bacterioscopy results were observed in 1724 clinical specimens. In the study period 18 clinical specimens obtained from children contained tubercle bacilli. In the period 2009-2013 we noted multi-drug resistant (MDR) strain in 41 clinical specimens, which made up 1.8% of strains with known results of drug-sensitivity. In 5 clinical specimens we observed extensively-drug resistant (XDR) strain, which made up 0.2% of strains with known results of drug-sensitiveness. 12 clinical specimens appeared to contain pre-XDR strain, which constituted 0.6% of strains with known results of drug-sensitivity., Summary and Conclusions: Despite advances in the diagnostics and treatment of tuberculosis (TB) this diseases still poses a serious medical problem. The detection level in the period 2009-2013 is relatively unchanged, with regards to both bacterioscopy and culture methods. Thus, the laboratory detection of tuberculosis bacilli is similar. It directly results from the enforcement of strict procedures regarding the quality of specimens collected for microbiological purposes and the control of the performed tests, which contributes to a greater number of confirmed cases of TB. In the study period the number of new cases of the infectious diseases is variable. Only in children this number remains stable over the years. Researchers observe that tubercle bacilli are resistant to basic first-line treatment drugs. They also note the occurrence of MDR, pre-XDR and XDR strains. Hence, it is important to regularly and carefully monitor the sensitivity of Mycobacterium tuberculosis to antibiotics administered in a long-term anti-tuberculosis therapy.

Archaea is a group of microorganisms described by Carl Woese in 1977. Although Archaea have a similar cellular organization to bacteria, their cell wall and cell membrane are quite unique. Archaeal cell wall lacks peptidoglican and cell membrane is composed of ether-lipids which are far more stable than bacteria-specific esther-lipids. Besides, Archaea have some specific external structures, like: archaella, pili, hami and cannulae but their exact functions are still unclear. Most of Archaea obtain energy via anaerobic processes of simple inorganic or organic compounds, however some of these organisms are also able to generate methane in the process known as methanogesis. They reproduce by cell division or budding-like process and some studies demonstrated the mechanisms of genetic transfer such as conjugation, transduction and natural transformation for the Archaea. They are capable of forming biofilms also in interaction with bacteria. Some archaeons, such as Haloferax mediterranei and Sulfolobus islandicus can synthesize antimicrobial agents which are called archaeocins. In recent years huge progress has been made in understanding of Archaea but many aspects of their biology remain still unknown. In this review, we present recent advances in Archaea biology focusing mainly on archaeal morphology, metabolism and reproduction.

Mast cells are numerous at anatomical sites close to external environment, virtually at the portals of infection. A few data indicated that these cells express cytoplasmic Toll-like receptors (TLRs) recognizing virus-derived molecules. Accordingly, mast cells could participate in anti-viral defense or/and in viral-related diseases. However, data concerning the influence of viruses on mast cell activity are limited. Thus, the aim of our study was to determine mast cell response to TLR7 ligand, i.e. resiquimod (R848), a synthetic mimic of viral ssRNA. Since mast cells play a central role in allergic reactions the effect of TLR7 agonist was also investigated on FcepsilonRI-dependent mast cell response. Experiments were carried out in vitro on freshly isolated fully mature rat peritoneal mast cells. Mast cells exhibit constitutive TLR7 molecule expression and its up-regulation after the agonist challenge. TLR7-mediated mast cell stimulation resulted in cysteinyl leukotriene (cysLT) and interferon (IFN)-beta synthesis, whereas no histamine and CXCL8 secretion was stated. Moreover, mast cell priming with TLR7 ligand caused the reduction in anti-IgE-induced histamine release. The results suggest that ssRNA viruses could directly activate mast cells to alter their phenotype and to release of potent proinflammatory mediators or indirectly modulate IgE-dependent allergic processes.

Archaea, along with bacteria and eucarya are the three domains of life. These microorganisms inhabit variable natural environments but they are also important part of human physiological flora. In this paper we describe archaeal morphology and physiology. We also review the state of knowledge about archaea associated with human microbiome. The potential role of these microorganisms in etiopathogenesis of some human diseases is discussed, as well. Finally, we consider archaeal susceptibility/resistance to antimicrobial agents, including antibiotics.