Anti-Bacterial Adhesion on Abiotic and Biotic Surfaces of the Exopolysaccharide from the Marine Bacillus licheniformis B3-15.

The eradication of bacterial biofilm represents a crucial strategy to prevent a clinical problem associated with microbial persistent infection. In this study we evaluated the ability of the exopolysaccharide (EPS) B3-15, produced by the marine Bacillus licheniformis B3-15, to prevent the adhesion and biofilm formation of Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 29213 on polystyrene and polyvinyl chloride surfaces. The EPS was added at different times (0, 2, 4 and 8 h), corresponding to the initial, reversible and irreversible attachment, and after the biofilm development (24 or 48 h). The EPS (300 µg/mL) impaired the initial phase, preventing bacterial adhesion even when added after 2 h of incubation, but had no effects on mature biofilms. Without exerting any antibiotic activity, the antibiofilm mechanisms of the EPS were related to the modification of the (i) abiotic surface properties, (ii) cell-surface charges and hydrophobicity, and iii) cell-to-cell aggregation. The addition of EPS downregulated the expression of genes (lecA and pslA of P. aeruginosa and clfA of S. aureus) involved in the bacterial adhesion. Moreover, the EPS reduced the adhesion of P. aeruginosa (five logs-scale) and S. aureus (one log) on human nasal epithelial cells. The EPS could represent a promising tool for the prevention of biofilm-related infections.

Hydrating Capabilities of the Biopolymers Produced by the Marine Thermophilic Bacillus horneckiae SBP3 as Evaluated by ATR-FTIR Spectroscopy.

The surfactin-like lipopeptide (BS-SBP3) and the exopolysaccharide (EPS-SBP3) produced by the polyextremophilic Bacillus horneckiae SBP3 (DSM 103063) have been recently described as valuable biopolymers useful in biotechnological applications. To investigate the hydrating capabilities of BS-SBP3 and EPS-SBP3, here we evaluated (i) their wetting properties, measuring the contact angle; (ii) their moisture uptake abilities using the gravimetric method; and (iii) their hydrating states (from 0 to 160% w/w of water content) using ATR-FTIR spectroscopy. BS-SBP3 reduced the water contact angle on a hydrophobic surface from 81.7° to 51.3°, whereas the contact angle in the presence of EPS-SBP3 was 72.9°, indicating that BS-SBP3 improved the wettability of the hydrophobic surface. In the moisture uptake tests, EPS-SBP3 absorbed more water than BS-SBP3, increasing its weight from 10 mg to 30.1 mg after 36 h of 100% humidity exposure. Spectral distance and cross-correlation analyses were used to evaluate the molecular changes of the two biopolymers during the hydration process. As the water concentration increased, BS-SBP3 spectra changed in intensity in the two contributions of the OH-stretching band named "closed" and "open" (3247 and 3336 cm-1, respectively). Differently, the spectra of EPS-SBP3 exhibited a broader peak (3257 cm-1), which shifted at higher water concentrations. As evaluated by the spectral distance and the wavelet cross-correlation analysis, the OH-stretching bands of the BS-SBP3 and EPS-SBP3 changed as a function of water content, with two different sigmoidal trends having the inflection points at 80% and 48%, respectively, indicating peculiar water-properties of each biopolymer. As wetting agents, these biopolymers might replace industrially manufactured additives in agriculture and the food and cosmetic industries.

Web-based analysis on the role of Digital Media in Health Communication: the experience of VaccinarSinSardegna Website.

BACKGROUND AND AIM: Vaccinarsinsardegna.org website is a medical and scientific communication portal regarding vaccinations of Sardinia region. This article aims to present the structure of the portal, to demonstrate the actions carried out to provide accurate information for users and to analyse the website's activity from its launch until the current pandemic period in terms of dissemination and visibility. METHODS: Various metrics such as the number of visits to the site (sessions, number of users and average session duration), user behaviour (pages viewed, bounce rate and organic search) and the session acquisition path (direct traffic, referrals and social traffic) were recorded, extrapolated and processed with Google Analytics. Qualitative and normally distributed quantitative variables were summarised with absolute (relative) frequencies and means. The statistical differences between the two periods (before and during the anti-COVID-19 vaccination campaign) were evaluated applying the Wilkoxon runk-sum test. A two-tailed p-value less than 0.01 was considered to be statistically significant. RESULTS: The metrics recorded using Google Analytics show that from its publication to date, the VaccinarSinSardegna.org portal has significantly increased its visibility: in fact, the number of users who have accessed the site, the number of sessions and individual web pages visited have grown exponentially. These findings are confirmed by the increasing number of visits to both versions of the regional website (Italian- and English-language) during the COVID-19 emergency and COVID-19 vaccination campaign. When the total values recorded over the period were compared, an overall increase in metrics was observed-the number of individual users, visits and individual pageviews rose in a statistically significant way. CONCLUSIONS: Based on the success on VaccinarSinSardegna and given its potential for expansion to include further collaborations with national and international scientific bodies, the authors affirm that similar initiatives should be implemented in the fight against vaccine hesistancy.

Influenza Vaccination Strategies in Healthcare Workers: A Cohort Study (2018-2021) in an Italian University Hospital.

Vaccinating healthcare workers (HCWs) is the most effective intervention for preventing nosocomial influenza infection. However, influenza vaccination coverage (VC%) among HCWs remains low. The aim of the study was to analyse the trend of VC% among healthcare workers in an Italian hospital through a three-year vaccination project covering three influenza seasons (2018-2019, 2019-2020, and 2020-2021). A gap analysis was performed at the case base (2018-2019), on-site vaccination was trialled in the 2019-2020 season, and an integrated vaccination offer (on-site vaccination and the classic offer at a vaccination clinic) was implemented for the 2020-2021 season. For each unit of vaccinated HCWs, the following variables were recorded: main demographic details, area of affiliation (medical/surgical/services), and professional category. Logistic regression analyses were performed to assess the relationship between outcome (undergoing vaccination in 2020-2021) and other variables related to the healthcare workers' characteristics. In the three seasons, VC% values of 13.2%. 27.7%, and 58.9% were recorded, respectively (p < 0.005). The highest VC% was recorded among physicians (94.93%), in the medical area (63.27%), and males (62.59%) and in general among the youngest HCWs. Comparison of the coverage values recorded in the three seasons showed that in the last season considered (2020-2021) about 80% of health workers preferred to be vaccinated in the workplace instead of using the standard vaccination delivery method (invitation to attend the vaccination clinic). Our study suggests that the integrated vaccination offer may lead to an increase in VC% among HCWs compared to the classical offer modalities.

Thermal restraint of a bacterial exopolysaccharide of shallow vent origin.

To dynamically characterize the thermal properties of the fructose-rich exopolysaccharide (EPS1-T14), produced by the marine thermophilic Bacillus licheniformis T14, the Attenuated Total Reflectance Fourier Transform Infra-Red spectroscopy was coupled to variable temperature ranging from ambient to 80°C. The spectra were analyzed by the following innovative mathematical tools: i) non-ideal spectral deviation, ii) OH-stretching band frequency center shift, iii) spectral distance, and iv) wavelet cross-correlation analysis. The thermal restraint analysis revealed that the whole EPS1-T14 system possessed high stability until 80°C, and suggested that fucose was mainly involved in the EPS1-T14 thermal stability, whereas glucose was responsible for its molecular flexibility. Our results provide novel insights into the thermal stability properties of the whole EPS1-T14 and into the role of its main monosaccharidic units. As a new biopolymer, the thermostable EPS1-T14 could be used in traditional biotechnology fields and in new biomedical areas, as nanocarriers, requiring high temperature processes.

Anti-herpes simplex virus 1 and immunomodulatory activities of a poly-γ- glutamic acid from Bacillus horneckiae strain APA of shallow vent origin.

Herpes simplex virus type 1 (HSV-1) is responsible of common and widespread viral infections in humans through the world, and of rare, but extremely severe, clinical syndromes in the central nervous system. The emergence of resistant strains to drugs actually in use encourages the searching for novel antiviral compounds, including those of natural origin. In this study, the recently described poly-γ-glutamic acid (γ-PGA-APA), produced by the marine thermotolerant Bacillus horneckiae strain APA, and previously shown to possess biological and antiviral activity, was evaluated for its anti-HSV-1 and immunomodulatory properties. The biopolymer hindered the HSV-1 infection in the very early phase of virus replication. In addition, the γ-PGA-APA was shown to exert low cytotoxicity and noticeable immunomodulatory activities towards TNF-α and IL-1ß gene expression. Moreover, the capacity to positively modulate the transcriptional activity of the cytokine genes was paired with increased level of activation of the transcription factor NF-kB by γ-PGA-APA. Overall, as non-cytotoxic biopolymer able to contribute in the antiviral defense against HSV-1, γ-PGA-APA could lead to the development of novel natural drugs for alternative therapies.

Preliminary Study on the In vitro and In vivo Effects of Asparagopsis taxiformis Bioactive Phycoderivates on Teleosts.

Several compounds from marine organisms have been studied for their potential use in aquaculture. Among the red algae, Asparagopsis taxiformis is considered one of the most promising species for the production of bioactive metabolites with numerous proposed applications. Here, the in vitro antibacterial activity, the easy handling and the absence of adverse effects on marine fish species are reported. Depending on the seasonal period of sampling, ethanol extracts of A. taxiformis exhibited significantly different inhibitory activity against fish pathogenic bacteria. The extract obtained in late spring showed strong antibacterial activity against Aeromonas salmonicida subsp. salmonicida, Vibrio alginolyticus, and V. vulnificus, and moderate activity against Photobacterium damselae subsp. damselae, P. damselae subsp. piscicida, V. harveyi and V. parahaemolyticus. Sea bass and gilthead sea bream were fed with pellets supplied with the alga and algal extracts. The absence of undesired effects on fish was demonstrated. Hematological and biochemical investigations allowed to confirm that the whole alga and its extracts could be proposed for a future application in aquaculture.

In Vitro Antibiofilm Activity of an Exopolysaccharide from the Marine Thermophilic Bacillus licheniformis T14.

The development of antibiofilm strategies is of major interest in contrasting bacterial pathogenic biofilms. A novel fructose and fucose rich exopolysaccharide (EPS1-T14) produced by the recently described thermophilic Bacillus licheniformis T14, isolated from a shallow hydrothermal vent of Panarea Island (Eolian Island, Italy), was evaluated for its effects on biofilm formation by multiresistant clinical strains of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus. The antibiofilm activity of EPS1-T14 was assessed by microtiter plate assays and visualized by confocal laser scanning microscopic images. EPS1-T14, with molecular weight of 1000 kDa, reduced biofilm formation on abiotic surfaces without affecting bacterial vitality. The novel EPS1-T14 is a water-soluble, noncytotoxic exopolymer able to prevent biofilm formation and its use may represent a promising therapeutic strategy for combating bacterial biofilm-associated infections. EPS1-T14 as antiadhesive biomolecule could be useful for novel prospective in medical and nonmedical applications.

Bacterial Exopolysaccharide of Shallow Marine Vent Origin as Agent in Counteracting Immune Disorders Induced by Herpes Virus.

Herpes simplex virus type 2 (HSV-2) is responsible of the continuously increasing viral infections in humans. In a previous study we demonstrated that the exopolysaccharide produced by Bacillus licheniformis strain B3-15 (EPS-B3-15), was able to hinder the HSV-2 replication in peripheral blood mononuclear cells (PBMC) and this antiviral activity appear to be related to a significant stimulation of the Th1-cytokines. In this study we analyse the role of EPS-B3-15 on Th2 cytokine production by PBMC infected or not with HSV-2. EPS-B3-15 demonstrate the ability to induce a particular cytokine network with consequent effects on the immune cells during HSV-2 infection.

Role of Bacterial Exopolysaccharides as Agents in Counteracting Immune Disorders Induced by Herpes Virus.

Extreme marine environments, such as the submarine shallow vents of the Eolian Islands (Italy), offer an almost unexplored source of microorganisms producing unexploited and promising biomolecules for pharmaceutical applications. Thermophilic and thermotolerant bacilli isolated from Eolian vents are able to produce exopolysaccharides (EPSs) with antiviral and immunomodulatory effects against Herpes simplex virus type 2 (HSV-2). HSV-2 is responsible for the most common and continuously increasing viral infections in humans. Due to the appearance of resistance to the available treatments, new biomolecules exhibiting different mechanisms of action could provide novel agents for treating viral infections. The EPSs hinder the HSV-2 replication in human peripheral blood mononuclear cells (PBMC) but not in WISH (Wistar Institute Susan Hayflic) cells line, indicating that cell-mediated immunity was involved in the antiviral activity. High levels of Th1-type cytokines were detected in PBMC treated with all EPSs, while Th2-type cytokines were not induced. These EPSs are water soluble exopolymers able to stimulate the immune response and thus contribute to the antiviral immune defense, acting as immunomodulators. As stimulants of Th1 cell-mediated immunity, they could lead to the development of novel drugs as alternative in the treatment of herpes virus infections, as well as in immunocompromised host.

Insulin resistance possible risk factor for cognitive impairment in fibromialgic patients.

To evaluate glucose metabolism and/or insulin resistance (IR) in 96 patients with Fibromyalgia (FM), associated or not to cognitive impairment. We investigated glucose metabolism in 96 FM patients. Enrolled patients were divided into two groups: 48 patients with memory deficit (group A) and 48 without memory deficit (control group). We evaluated glucose and insulin levels after a 2 h-Oral-Glucose-Tolerance-Test (2 h-OGTT) and insulin resistance (IR) by the homeostasis model assessment formula (HOMA). Body Mass Index (BMI), waist-to-hip-ratio (WHR), anxiety level, fasting plasma insulin and Non-Steroidal Anti-Inflammatory agents use were higher in patients with FM with memory impairment; while age, sex, waist circumference, education level, fasting plasma glucose, glycate hemoglobin, triglycerides, blood lipid profile, C- Reactivity-Protein (CRP), blood pressure and smoking habits were similar in both groups. Following OGTT the prevalence of glucose metabolism abnormalities was significantly higher in group A. IR was present in 79% patients, of whom 23% had also impaired glucose tolerance, 4% newly diagnosed diabetes mellitus and 52% IR only. Obesity and overweight prevailed in group A. IR, but not BMI or WHR was associated to an increased risk of memory impairment (OR = 2,6; 95% CI: 1,22-3,7). The results of this study suggest that IR may represent a risk factor for memory impairment in fibromialgic patients.

A novel EPS-producing strain of Bacillus licheniformis isolated from a shallow vent off Panarea Island (Italy).

A haloalkaliphilic, thermophilic Bacillus strain (T14), isolated from a shallow hydrothermal vent of Panarea Island (Italy), produced a new exopolysaccharide (EPS). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain T14 was highly related (99 % similarity) to Bacillus licheniformis DSM 13(T) and Bacillus sonorensis DSM 13779(T). Further DNA-DNA hybridization analysis revealed 79.40 % similarity with B. licheniformis DSM 13(T) and 39.12 % with B. sonorensis DSM 13779(T). Sucrose (5 %) was the most efficient carbon source for growth and EPS production. The highest EPS production (366 mg l(-1)) was yielded in fermenter culture at 300 rpm after 48 h of incubation. The purified fraction EPS1 contained fructose/fucose/glucose/galactosamine/mannose in a relative proportion of 1.0:0.75:0.28:tr:tr and possessed a molecular weight of 1,000 kDa displaying a trisaccharide unit constituted by sugars with a ß-manno-pyranosidic configuration. Screening for biological activity showed anti-cytotoxic effect of EPS1 against Avarol in brine shrimp test, indicating a potential use in the development of novel drugs.

Effects of insulinic therapy on cognitive impairment in patients with Alzheimer disease and diabetes mellitus type-2.

BACKGROUND: Type-2 Diabetes Mellitus (DM-2) is an important risk factor for Alzheimer disease (AD) and vascular dementia (VD). The role of insulinic therapy on cognitive decline is controversial. OBJECTIVE: To evaluate cognitive impairment in patients with AD and DM-2 treated with either oral antidiabetic drugs or combination of insulin with other diabetes medications. METHODS: 104 patients with mild-to-moderate AD and DM-2 were divided into two groups, according to antidiabetic pharmacotherapy: group A, patients treated with oral antidiabetic drugs and group B, patients treated with insulin combined with other oral antidiabetic medications. Cognitive functions were assessed by the Mini Mental State Examination (MMSE) and the Clinician's Global Impression (CGI), with a follow-up of 12 months. RESULTS: At the end of the study, the MMSE scores showed a significant worsening in 56.5% patients of group A and in 23.2% patients of group B, compared to baseline MMSE scores (P=.001). Also CGI-C scores showed a significant worsening for all domains after 12 months in group A vs group B (P=.001). The two groups were matched for body mass index, serum lipids, triglycerides, Apo epsilon4 allele and smoke habit. Conversely, ischemic heart disease and hypertension were significantly higher in group B (P=.002). After adjustment for this risk variables, our results remained significant (P=.001). CONCLUSIONS: Our study suggests that insulinic therapy could be effective in slowing cognitive decline in patients with AD.