The Lactobacillus flora in vagina and rectum of fertile and postmenopausal healthy Swedish women

<p>Abstract</p> <p>Background</p> <p><it>Lactobacillus </it>species are the most often found inhabitants of vaginal ecosystem of fertile women. In postmenopausal women with low oestrogen levels, <it>Lactobacillus </it>flora is diminishing or absent. However, no studies have been performed to investigate the correlation between oestrogen levels and the lactobacilli in the gut. The aim of the present study was to investigate the relation in healthy women between vaginal and rectal microbial flora as well as possible variations with hormone levels.</p> <p>Methods</p> <p>Vaginal and rectal smears were taken from 20 healthy fertile women, average 40 years (range 28-49 years), in two different phases of the menstrual cycle, and from 20 postmenopausal women, average 60 years (range 52-85 years). Serum sex hormone levels were analyzed. Bacteria from the smears isolated on Rogosa Agar were grouped by Randomly Amplified Polymorphic DNA and identified by multiplex PCR and partial 16S rRNA gene sequencing.</p> <p>Results</p> <p><it>Lactobacillus crispatus </it>was more often found in the vaginal flora of fertile women than in that of postmenopausal (p = 0.036). Fifteen of 20 fertile women had lactobacilli in their rectal smears compared to 10 postmenopausal women (p = 0.071). There was no correlation between the number of bacteria in vagina and rectum, or between the number of bacteria and hormonal levels. Neither could any association between the presence of rectal lactobacilli and hormonal levels be found.</p> <p>Conclusion</p> <p><it>Lactobacillus crispatus </it>was more prevalent in the vaginal flora of fertile women, whereas the <it>Lactobacillus </it>flora of rectum did not correlate to the vaginal flora nor to hormonal levels.</p

Commercially available natural inhibitors of trichothecene production in Fusarium graminearum: A strategy to manage Fusarium head blight of wheat

Fusarium Head Blight (FHB) is one of the most important diseases affecting wheat production. The disease causes yield and quality losses and hinders commercialization because of frequent grain contamination with trichothecenes, sesquiterpene mycotoxins that are harmful to human and animals and act as pathogenicity factors for FHB. Although not always effective, application of fungicides is the most common method for FHB management; thus, there is an urgent need to develop new efficient and sustainable tools. We analyzed the inhibitory activity of a group of commercially available naturally occurring compounds on the production of trichothecenes and on the severity of FHB on field-grown wheat spikes inoculated with Fusarium graminearum. The gene TRI5 codifies trichodiene synthase, the enzyme that catalyzes the synthesis of trichodiene, a volatile intermediate to trichothecenes. Our first aim was to obtain a trichothecene non-producing mutant of the pathogen by gene disruption of this gene. Seventeen putative ΔTRI5 mutants produced in the laboratory were characterized for pathogenicity and trichothecene production. The target gene was correctly and efficiently replaced in more than 75% of the transformants obtained, indicating a high efficacy of the approach used for gene disruption. Selected commercially available natural inhibitors -eugenol, apocynin, caffeic acid and propyl gallate-, were used to test their effect on trichodiene production in vitro and in field-grown wheat spikes inoculated with F. graminearum, using a ΔTRI5 mutant as non-trichodiene production control. Fungal volatile organic compounds production was measured by gas chromatography coupled to mass spectrometry. Caffeic acid, apocynin and eugenol produced a significant reduction of trichodiene production in vitro. In field assays, sesquiterpene inhibition was also significant at 2 days post inoculation (dpi), showing that effective inhibition of the trichothecene precursor can be achieved through the action of commercially available naturally occurring compounds. However, at later stages (>7 dpi) the production of trichodiene was similar to that of the F. graminearum-inoculated control. At 21 dpi, FHB severity did not differ between the treatments with inhibitors and the inoculated control. Hence, further experiments are required to identify the most appropriate inhibitors concentrations and formulations to improve their bioavailability and to achieve long lasting protection against F. graminearum infections.Fil: Malbrán, Ismael. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Departamento de Ciencias Biológicas. Centro de Investigaciones de Fitopatología. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones de Fitopatología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Mourelos, Cecilia Alejandra. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Departamento de Ciencias Biológicas. Centro de Investigaciones de Fitopatología. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones de Fitopatología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Pardi, Martín. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Oufensou, Safa. Università Degli Studi Di Sassari; ItaliaFil: Balmas, Virgilio. Università Degli Studi Di Sassari; ItaliaFil: Delogu, Giovanna. Istituto Di Chimica Biomolecolare; ItaliaFil: Migheli, Quirico. Università Degli Studi Di Sassari; ItaliaFil: Lori, Gladys. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Departamento de Ciencias Biológicas. Centro de Investigaciones de Fitopatología. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones de Fitopatología; ArgentinaFil: Juarez, Marta Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Girotti, Juan Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; Argentin