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Sex hormones are often administered to mice in vaginal microbial studies in order to synchronize estrous. Our objective was to evaluate the effect of estradiol-hemisuccinate (EH) or medroxyprogesterone-acetate (MPA) administration on estrous cycle, vaginal microbiota, and immune cell populations of various organs in a murine model. Two-month-old female BALB/c mice were intramuscularly injected with EH (day -2) or MPA (day -5) to induce estrous (E) or diestrous (DE), respectively. On sampling days (Sd) 0, 2, 6 and 8, vaginal washings (v.w.), vagina, blood, spleen and bone marrow (BM) samples were taken. Most of the animals remained in E or DE states until Sd 6 after EH or MPA administration, respectively. The number of cultivable vaginal bacteria was not modified by hormonal treatments; higher quantities were detected in mice in E. Only EH administration modified serum sex hormone levels, increasing serum estradiol on Sd 0. In v.w., myeloid population was dominant while lymphoid populations were not detected. Only MPA administration induced a reduction in myeloid cells on Sd 0. Hormonal treatments did not affect myeloid populations in BM but caused a slight decrease in T and B cells. In spleen, hormonal administration did not affect B or T population size while an increase in mature B cells and a decrease in immature B cells were observed in MPA-treated mice compared with EH-treated mice. Thus, although both hormonal treatments induced slight changes in some of the parameters evaluated compared to control animals, adequately standardized and consistent experimental protocols were established for further studies., Scandinavian Journal of Laboratory Animal Sciences, Vol. 44 (2018)

Organic compounds have been produced for industrial applications for decades and they are some of the widest spread and most persistent pollutants found in air, water, and sediments. Those so-called persistent organic pollutants (POPs) include to polycyclic aromatic hydrocarbons (PAHs) comprising several of the most prioritized compounds on the US EPAs lists because of its detrimental biological effects, including toxicity, mutagenicity, and carcinogenicity. Its remediation is a priority. A wide diversity of bacteria has been isolated from soils and sediments with the ability to use PAHs as their sole carbon and energy source. The objective of this chapter is to provide an overview of the strategies for bioremediation of PAHs by immobilized biomass and biotransformation that have been applied based on the benefits from the biofilm mode of growth. In the following sections, general concepts about some microbial immobilization processes will be explained. In later sections, different case studies concerning microbial immobilization systems used for hydrocarbon decontamination in waters and soils will be reviewed. Fil: Alessandrello, Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Juárez Tomás, María Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina Fil: Isaac, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Transferencia de Villa María. Universidad Nacional de Villa María. Centro de Investigaciones y Transferencia de Villa María; Argentina Fil: Vullo, Diana Lia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de General Sarmiento; Argentina Fil: Ferrero, Marcela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina

Aims: To evaluate the phenotypic expression of auto-aggregation, adhesion to mucin and biofilm formation of lactobacilli isolated from human vagina and the presence of related genes. Methods and Results: Seven different strains of three Lactobacillus species (Lactobacillus gasseri, Lactobacillus rhamnosus and Lactobacillus reuteri) were evaluated. The auto-aggregation property was determined by spectrophotometric assay and flow cytometry. Adhesion and biofilm formation were assayed by crystal violet staining. The presence of the genes encoding sortases, pilin subunits and surface proteins was evaluated by polymerase chain reactions. The two Lact. reuteri strains assayed showed high auto-aggregation, adhesion to mucin and biofilm formation ability. In these strains, the genes encoding three adhesion proteins were identified. In Lact. rhamnosus CRL (Centro de Referencia para Lactobacilos Culture Collection) 1332, pilus-encoding genes were detected. In all Lact. rhamnosus strains assayed, two genes encoding for other surface proteins related to adhesion and biofilm formation were detected. Conclusions: The vaginal lactobacilli assayed exhibited phenotypic and genetic characteristics that were specific for each strain. Significance and Impact of the Study: This is the first study on auto-aggregation, adhesion and biofilm formation of vaginal Lactobacillus strains by phenotypic and genetic assays. Fil: Leccese Terraf, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina Fil: Mendoza, Lucia Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina Fil: Juárez Tomás, María Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina Fil: Silva, C.. Universidad Nacional de Tucumán; Argentina Fil: Nader, Maria Elena Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina

Lactic acid bacteria are constituents of most of the indigenous microbiota or mucosarelated ecosystems, both in humans or animals. During the last years, many bacteriocins produced by bacteria classified into this group were described. Bacteriocins are ribosomally-synthesized antimicrobial peptides produced by a wide range of bacteria. Historically, they were used as bioactive compounds to prevent the growth of pathogen or spoilage microorganisms in foods. The most widely used is nisin, produced by Lactococcus lactis, that is included in the CODEX and has the GRAS (Generally Recognized as Safe) status to be incorporated into different types of processed or longterm storage foods. As bacteriocins are active against many pathogens, potentially pathogens or some drug-resistant pathogens, some of them have been thought as alternative bioactive substances to avoid the broad side-effects and alarming resistance dissemination produced by the use of classical antibiotics. Our research group is working in the design of a beneficial product to prevent prevent women urogenital infections, and we were the first to describe salivaricin CRL 1328, a bacteriocin produced by Lactobacillus salivarius isolated from human vagina. This bioactive compound is heat-stable, and active against a wide variety of urogenital pathogens. The molecular characterization of salivaricin indicates that is constituted by two structural peptides and the evaluation of the mechanism of action reveals that acts by dissipating the proton motive force of the sensitive pathogens. As we are interested to incorporate salivaricin into a pharmaceutical product, the optimization of the culture media and physico-chemical conditions for the higher production were determined. And also the stability to the freeze-drying process and to the long term storage conditions was studied. Some of these experiments were performed by the application of statistical methods that allowed a faster and easier interpretation of the experimental results obtained. The incorporation of bacteriocins as bioactive compounds in a pharmaceutical product needs different type of studies to demonstrate the no existence of adverse effects, which must be performed both in in vitro and in in vivo experimental systems. Most of the bacteriocins do not exert significant cytoxicity or hemolytic activity against human erythrocytes in in vitro assays. Experiments in animal models have shown the success of some lantibiotics for the treatment of infections produced by Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA), and also in the prevention of gingivitis. Nisin is included into a pharmaceutical product to prevent cow mastitis, and is proposed as spermicidal for human use. In this chapter, a revision of many of the bacteriocins described for prevention of human health are reviewed, together with those available commercially, evaluated by in vitro or in vivo assays. Up today, the use of bacteriocins as bioactive compounds into pharmaceutical products for human use has not been accepted yet by the regulators or reference organizations. There are a wide variety of bacteriocins produced by different bacterial genera that must be further studied. More complex experiments are needed to encourage and support the inclusion of these types of bioactive substances into products that could be applied to prevent or treat many of the wide arrays of pathogenic microorganisms that affect human and animal health. Fil: Nader, Maria Elena Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina Fil: Vera Pingitore, Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina Fil: Juárez Tomás, María Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina