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This study characterizes mycorrhiza helper bacteria (MHB) from selected unpolluted locations as well as subjected to industrial emissions. To determine the species of bacteria isolated from the roots of ectomycorrhizal pine and birch, a method based on the sequence analysis of a 16S rRNA gene was used. The isolated bacteria were initially characterized by available biochemical methods and phenotypic observation. On the selected bacteria representatives isolation of DNA was performed, on which the PCR reaction was carried out. In this way amplified samples were automatically sequenced and the obtained results were compared to public databases. Among the isolated bacteria Pseudomonas fluorescens SBW25 and Burkholderia xenovorans LB400 species were dominant.

It is estimated that each year more than 2 million people suffer from diarrheal diseases, resulting from the consumption of contaminated meat. Foodborne infections are most frequently caused by small Gram-negative rods Campylobacter. The hosts of these bacteria are mainly birds wherein they are part of the normal intestinal flora. During the commercial slaughter, there is a likelihood of contamination of carcasses by the bacteria found in the intestinal content. In Europe, up to 90% of poultry flocks can be a reservoir of the pathogen. According to the European Food Safety Authority report from 2015, the number of reported and confirmed cases of human campylobacteriosis exceeds 200 thousands per year, and such trend remains at constant level for several years. The occurrence of growing antibiotic resistance in bacteria forces the limitation of antibiotic use in the animal production. Therefore, the European Union allows only using stringent preventive and hygienic treatment on farms. Achieving Campylobacter free chickens using these methods is possible, but difficult to implement and expensive. Utilization of bacterial viruses - bacteriophages, can be a path to provide the hygienic conditions of poultry production and food processing. Formulations applied in the food protection should contain strictly lytic bacteriophages, be non-pyrogenic and retain long lasting biological activity. Currently, on the market there are available commercial bacteriophage preparations for agricultural use, but neither includes phages against Campylobacter. However, papers on the application of bacteriophages against Campylobacter in chickens and poultry products were published in the last few years. In accordance with the estimates, 2-logarithm reduction of Campylobacter in poultry carcases will contribute to the 30-fold reduction in the incidence of campylobacteriosis in humans. Research on bacteriophages against Campylobacter have cognitive and economic importance. The paper presents current state of research on bacteriophages targeted against Campylobacter. [ABSTRACT FROM AUTHOR]

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Interferons are a family of proteins that are released by a variety of cells in response to infections caused by viruses. Currently, we distinguish three types of interferons. They are classified based on the nucleotide sequence, interaction with specific receptors, chromosomal location, structure and physicochemical properties. The following interferons are classified as type I: α, β, ω, κ, ε, ζ, τ, δ, ν. They are recognized and bound by a receptor formed by two peptides, IFN-αR1 and IFN-αR2. Representative of type II interferons is interferon-γ. It binds to a receptor composed of chains IFNGR-1 and IFNGR-2. The recently classified type III interferons comprise IFN-λ1, IFN-λ2, and IFN-λ3. They act on receptors formed by λR1 IFN-and IL-10R2 subunits. A high level of antiviral protection is achieved by IFN-α, IFN-β and IFN-λ. Antiviral activity of interferons is based on the induction and regulation of innate and acquired immune mechanisms. By binding to transmembrane receptors, IFN interacts with target cells mainly by activating the JAK/STAT, but also other signaling pathways. This leads to induction and activation of many antiviral agents, such as protein kinase RNA-activated (PKR), ribonuclease 2-5A pathway, and Mx proteins, as well as numerous apoptotic pathways. As a result of the protective effect of interferons, the virus binding to cells and viral particles penetration into cells is stopped, and the release of the nucleocapsid from an envelope is suppressed. Disruption of transcription and translation processes of the structural proteins prevents the formation of virions or budding of viruses, and as a result degradation of the viral mRNA; the started processes inhibit the chain synthesis of viral proteins and therefore further stimulate the immune system cells.

All-trans retinoic acid (ATRA) is considered to be a potential chemotherapeutic drug due to its capability to regulate cell growth and differentiation. The effects of ATRA on the proliferation of cells and gene regulation are mediated by retinoid receptors (RAR and RXR), which belong to the nuclear receptor superfamily of ligand- inducible transcription factors. ATRA can act either as a growth inhibitor or growth promoter, according to the functional state of retinoic receptors. Thus, we have established the effect of ATRA on the proliferation of cervical cancer cells line HeLa and CaSki and expression of retinoids receptors as well as the viral HPV oncogenic proteins E6 and E7. ATRA had no effect on proliferation CaSki cells, but it stimulated the growth of HeLa cells, which depended on the incubation time and the concentration of ATRA in cell culture. The overexpression of RAR alpha in HeLa cells after the administration of 10(-7) mM ATRA was also observed 72 hours, and the decrease of CaSki by 60-90%. In the study of cervical cancer cell lines, the very low levels of other endogenous RAR and RXR receptors were observed. ATRA does not repress the expression of two viral oncoproteins E6 and E7 HPV16/18, which play a key role in carcinogenesis of the cervix. Our results support the suggestions that the cell response to vitamin A, and other retinoids in the diet, may depend on cell type, and that the cancer cells are differentially resistant to retinoids. Thus, despite the important biological functions of retinoids, the effects of retinoids in a supplementation in supra-physiological doses as well as their physiological action are difficult to define.

The ectocervical epithelium is the target of the oncogenic human papillomavirus (HPV), which acts as an etiological agent in the development of cervical carcinoma. However, the HPV-mediated transformation of human epithelial cells is a multi-step process dependant on unknown factors additional to the virus, which is a necessary but, in and of itself, insufficient catalyst. In the present study, we characterized the role of insulin-like growth factor-I (IGF-I) in this process. IGF-I is an endocrine hormone with an autocrine and paracrine role in many tissues. Our data demonstrated that autocrine secretion of IGF-I can contribute to HPV-induced carcinogenesis of the epithelium. An immunohistochemical study showed that IGF-I was present in the nuclei of the reproductive layer of the paraepidermal epithelium in 89% of cases of intraepithelial neoplasia (CIN I-III) and 60% of cases of invasive cervical cancer. The presence of IGF-I at a nuclear localization in the cells studied suggests that it may also have intranuclear actions.