Emanuela Vittoria

Retention of virulence in viable but non-culturable halophilic Vibrio spp.

The viable but non-culturable (VBNC) forms of two environmental strains of Vibrio alginolyticus 1 and Vibrio parahaemolyticus 66 and one strain of V. parahaemolyticus ATCC 43996 showing virulence characteristics (hemolysin production, adhesive and/or cytotoxic ability, in vivo enteropathogenicity) were obtained by culturing bacteria in a microcosm consisting of artificial sea water (ASW) and incubating at 5 degrees C with shaking. Every 2 days, culturability of the cells in the microcosm was monitored by spread plates on BHI agar and total count and the percentage of viable cells were determined by double staining with DAPI and CTC. When cell growth was not detectable (<0.1 CFU/ml), the population was considered non-culturable and, then, the VBNC forms were resuscitated in a murine model. For each strain, eight male Balb/C mice were intragastrically inoculated with 0.1 ml of concentrated ASW bacterial culture. Two mice from each group were sacrificed at 2, 4, 8, and 12 days after challenge for autopsy and re-isolation of the microorganisms from the intestinal tissue cultures. Isolation was obtained in 25% of the animals challenged with the VBNC V. alginolyticus strain, in 37.5% of those challenged with the VBNC V. parahaemolyticus strain of environmental origin and in 50% of the animals infected with VBNC V. parahaemolyticus ATCC 43996. The strains thus isolated were again subjected to biological assays to determine the retention of pathogenicity. The virulence characteristics that seemed to disappear after resuscitation in the mouse were subsequently reactivated by means of two consecutive passages of the strains in the rat ileal loop model. The results obtained indicate that VBNC forms of the strains examined can be resuscitated and retain their virulence properties.

Microbiological study of cosmetic products during their use by consumers: health risk and efficacy of preservative systems

Aim:  To evaluate the microbial contamination of 91 cosmetics (23 o/w emulsions, 47 tensiolytes, 21 aqueous pastes) in three different states of use (intact, in‐use, ending product) and the protection efficacy of the preservative systems most frequently used in the analysed cosmetic formulations.

In Vitro Synergistic Activities of Essential Oils and Surfactants in Combination with Cosmetic Preservatives Against Pseudomonas aeruginosa and Staphylococcus aureus

The aim of this study is to evaluate possible synergistic antimicrobial interactions between common cosmetic preservatives and selected essential oils or surfactants. The antimicrobial efficacy of six essential oils, three surfactants and five preservatives against Pseudomonas aeruginosa ATCC 9027 and Staphylococcus aureus ATCC 43387 was assessed by a broth micro-dilution assay. MICs for individual and combined antimicrobials were determined and then transformed to fractional inhibitory concentration (FIC) indexes. All essential oils exhibited antibacterial activity; among surfactants, bacteria resulted most susceptible to the cationic agent. Synergy was observed when essential oils of eucalyptus and mint were combined with methylparaben against P. aeruginosa, while essential oils of mint, oregano and sage combined with propylparaben and imidazolidinyl urea acted against S. aureus. Many binary mixtures of preservatives and surfactants produced synergistic activity with the most effective interactions involving the cationic and amphoteric compounds under study. FIC indexes demonstrated synergistic effects when preservatives were combined with either essential oils or surfactants against both bacterial strains. These results highlight the potential usefulness of essential oils and surfactants to enhance the activities of conventional biocides. This kind of study should contribute to the selection and optimization of preservative systems for cosmetic preparations.

Antimicrobial Activity of Two Propolis Samples Against Human Campylobacter jejuni

The aim of this study was to analyze the antimicrobial activity of two ethanolic extracts of propolis (EEPs) and selected flavonoids against 16 Campylobacter jejuni clinical isolates and several Gram-positive and Gram-negative human pathogens. The antimicrobial activity of EEPs and flavonoids was evaluated by the agar well diffusion method. The EEPs inhibited the growth of C. jejuni, Enterobacter faecalis, and Staphylococcus aureus. The most active flavonoid was galangin, with the highest percentage of sensitivity among C. jejuni strains (68.8%); lower percentages of sensitivity were observed for quercetin (50%). The minimal inhibitory concentrations (MICs) of EEPs and flavonoids for C. jejuni isolates were determined by the agar dilution method. EEPs showed MIC values of 0.3125-0.156 mg/mL for all C. jejuni strains; galangin and quercetin gave MICs ranging from 0.250 to 0.125 mg/mL. Thus propolis preparations could be used as support to traditional therapy for Campylobacter infection, especially when the antibiotic agents show no activity against this microorganism.

OSAS: valutazione della patologia e patente professionale

La sindrome delle apnee ostruttive del sonno e una patologia che colpisce indistintamente maschi e femmine. La OSAS (Obstructive Sleep Apnea Syndrome) e determinata da episodi ripetuti di ostruzione parziale o completa delle vie aeree superiori. I disturbi del sonno non solo si ripercuotono negativamente sulla salute e sulla qualita della vita di chi ne soffre, ma aumentano anche i rischi sulle strade. Il 19 febbraio 2016 e stato pubblicato sulla Gazzetta Ufficiale n. 41 il decreto dirigenziale 3 febbraio 2016 del Ministero della Salute, che fornisce gli indirizzi medico-legali da osservare per l’accertamento dell’idoneita psico-fisica alla guida per coloro che sono affetti, o che si sospetta possano essere affetti, da OSAS. The syndrome of obstructive sleep apneee is a condition that affects males and females without distinction. OSAS (Obstructive sleep apnea syndrome) is advanced by Repeated episodes of partial or complete obstruction of the upper airway. Sleep disorders not only have a negative effect on the health and quality of life of those who suffer, but also increase the risks on the roads. On February 19, 2016 it was published in the Official Gazette no. 41 of the Ministry of Health Decree of 3 February 2016, which contains the medical-legal guidelines to be observed for the assessment of the psycho-physical fitness to guide those who are affected, or who are suspected of being affected, by OSAS