Pasqualina Laganà

Natural iron chelators: Protective role in A549 cells of flavonoids-rich extracts of Citrus juices in Fe(3+)-induced oxidative stress.

Exogenous iron in particulate matter and imbalanced iron homeostasis cause deleterious effects on health. Natural and synthetic iron chelators may be of therapeutic benefit, therefore we evaluated the protective effect of Citrus flavonoids-rich extracts from bergamot and orange juices in iron overloaded human lung epithelial cells. Cytofluorimetric, biochemical and genotoxic analyses were performed in Fe2(SO4)3 exposed A549, pretreated with each extract whose chemical composition was previously detected. Chelating activity was assessed in cells by a calcein ester. Both extracts reduced the generation of reactive oxygen species and membrane lipid peroxidation, improved mitochondrial functionality, and prevented DNA-oxidative damage in iron-exposed cells. Antioxidant effects were attributed to the chelating property, blocking upstream the redox activity of iron. Flavonoid-rich extracts also induced antioxidant catalase. The bergamot and orange juice extracts had a broad-spectrum protective effect. Their use prevents iron oxidative injury and these natural iron chelators could be used as therapeutic agents.

Legionella spp., amoebae and not-fermenting Gram negative bacteria in an Italian university hospital water system

INTRODUCTION In hospital and other health care facilities, contamination of water systems by potentially infectious microorganisms, such as bacteria, viruses and protozoa, is a source of nosocomial infections, which may originate fromcolonization of water pipes, cooling towers, spa pools, taps, showers and water supplies. Objective. The study focuses on the occurrence of Legionella spp., free-living amoebae and non-fermenting Gram-negative microorganisms in a University hospital water system located in the town of Messina (Sicily, Italy), which had never been examined previously. MATERIALS AND METHODS From January 2008 - March 2009, hot tap water samples were collected from 10 wards. Legionella spp. recovered on selective culture medium were identified by microagglutination latex test; free-living amoebae were cultured using Escherichia coli as a food source. Non-fermenting Gram negative microorganisms were identified by API 20 NE strips. RESULTS Legionella spp. were found in 33.33% of the samples. L. pneumophila serogroup 1 was recovered from the Laboratory Diagnostic and Anaesthesia-Neurology Wards, with a peak of 3.5 × 10(4) cfu/L in May 2008. L. pneumophila serogroups 2-14 were found in the Othorhinolaryngology, Pathologic Anatomy, Paediatrics and Surgery Wards, and peaked (4 × 10(4) cfu/L) in April 2008. Pseudomonadaceae and Hyphomycetes were also detected. Legionella spp. were recovered from samples positive for non-pathogenic amoebae Hartmannella spp. CONCLUSION This first study of a Messina hospital water system suggested potential health risks related to the detection of Hartmannella spp., as reservoirs for Legionella spp., and Pseudomonas aeruginosa, a Gram negative non-fermenting bacterium frequently causing nosocomial pneumonia. The urgent need for monitoring programmes and prevention measures to ensure hospital water safety is stressed.

Serological and molecular identification of Legionella spp. isolated from water and surrounding air samples in Italian healthcare facilities

BACKGROUND Legionella is an intracellular microorganism living in natural and artificial aquatic environments. Although its transmission to humans is linked to the inhalation of contaminated aerosols, there is no validated air sampling method for the control and prevention of the disease. The aim of the present study was to provide more information on the distribution of Legionella spp. in indoor environments and to determine whether the same Legionella strains are isolated from air and water samples. METHODS Ten healthcare facilities located in seven regions of Italy were enrolled. The serological typing of Legionella spp. from water samples and the surrounding air by active and passive sampling was assessed using polyvalent and monovalent antisera. Subsequently, the strains identified as Legionella pneumophila (Lpn) underwent molecular typing by sequence-based typing (SBT) using seven genes (flaA, pilE, asd, mip, mompS, proA, and neuA). The allelic profile number was assigned using the European Working Group for Legionella Infections-SBT database. RESULTS Lpn serogroup 6 was the most prevalent serogroup; it was found simultaneously in the air and water samples of three different healthcare facilities. In the remaining seven hospitals, Lpn serogroups 1, 6, 7, 9, and 12 were isolated exclusively from water samples. The molecular investigation showed that Lpn strains in the water and air samples of each positive healthcare facility had the same allelic profile. Strains, identified as sequence types (STs) 728 and ST 1638+ST 1324, were isolated in two respective healthcare facilities, and a new strain, identified as ST 1989, was obtained in one healthcare facility. CONCLUSION The application of the SBT method allowed to verify the homology among Legionella strains from water samples and the surrounding air. The results showed that the same Lpn strains were present in the air and water samples, and a new Legionella strain was identified.

Psoriasis and Cardiovascular Risk: Correlation Between Psoriasis and Cardiovascular Functional Indices:

Evidence suggests that psoriasis together with other cardiovascular (CV) risk factors is associated with increased vascular morbidity, but it is not clear whether psoriasis is an independent risk factor. Consecutive patients (n = 33; 35.6 ± 5.7 years; 13 females) with mild psoriasis (Psoriasis Area and Severity Index <10) without comorbidities and 33 healthy participants (36.3 ± 5.9 years; 15 females) were enrolled. Both groups underwent echocardiography, speckle tracking (2-dimensional strain echocardiography [2D-SE]), and pulse wave velocity (PWV) testing. Clinical and conventional echocardiographic characteristics were comparable between both groups. Global longitudinal strain (GLS) was significantly lower (P = .002) in the psoriasis group (22.39% ± 2.28%) than in controls (24.15% ± 2.17%). The PWV was significantly lower (P = .004) in controls (8.06 ± 1.68 m/s) than in the psoriasis group (9.23 ± 1.53 m/s). Significant correlations between GLS and disease duration (r = −.66, P < .0001) and between GLS and patient age at diagnosis (r = .48, P = .0043) were found. Psoriasis may be an independent CV risk factor, causing cardiac and vascular impairment. Both 2D-SE and PWV may be useful tools for the screening of CV risk in these patients.

Evaluation of Legionella Air Contamination in Healthcare Facilities by Different Sampling Methods: An Italian Multicenter Study

Healthcare facilities (HF) represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis®μ) and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis®μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT) methods. Air contamination was found in four HF (36.4%) by at least one of the culturable methods. The culturable investigation by Coriolis®μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis®μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations.

Chemistry and Hygiene of Food Additives

Chemistry and hygiene of food additives. , Chemistry and hygiene of food additives. , کتابخانه دیجیتالی دانشگاه علوم پزشکی و خدمات درمانی شهید بهشتی

Brief Notes About Biofilms

The biofilm is a microbial community characterised by sessile bacterial cells strongly adherent to a substrate and/or an interface and incorporated in a polymeric matrix of microbial origin. In this condition, microbial cells exhibit an altered phenotype in comparison to corresponding free or planktonic forms. Life in a biofilm represents probably the prevailing mode of growth for microbes in several environments. After the development of new observation methods and the modification of different procedures, biofilms may be identified on known substrates and on new sites. The concept of biofilm has acquired the importance that still plays in the health sector, especially in areas where the use of invasive instruments and the continuous temporal localisation is expected. An important role is also played in the food industry because of the direct presence on food surfaces.

Biological Toxins from Marine and Freshwater Microalgae

In the last decades the increased occurrence of intoxications caused by biological toxins produced from marine and freshwater microalgae has underlined their relevance as emerging risks for food safety. Biological toxins from algae (i.e. saxitoxin, brevetoxin, okadaic acid, domoic acid) are recognised as a major threat for human and animal health, especially where Harmful Algal Blooms phenomena develop. Many of these toxins are responsible for severe illness or death, mostly related to consumption of seafood contaminated by toxic algae. The present book summarises current knowledge and perspectives for future research on marine and freshwater algal toxins. Specific topics are: overview of the different species producing toxins, their survival strategies in the environment; typologies of toxins, their chemical structure and mechanisms of actions; methods currently in use for their monitoring; emerging issues and future outlooks for their control. The importance of biotoxin monitoring in the framework of the European Marine Strategy Framework Directive is also discussed.

Bacterial isolates from the Arctic region (Pasvik River, Norway): assessment of biofilm production and antibiotic susceptibility profiles

Bacterial biofilm production is recognized as a strategy that helps aquatic bacteria in resisting to the presence of several kinds of pollutants, including antibiotics, in the bulk environment. The Pasvik River, located between Norway, Russia and Finland, is a sub-Arctic site polluted by wastes from metallurgic and mining activities. In order to study whether and to what extent bacteria are able to produce biofilms, and to assess whether this physiological characteristic influences their resistance to antibiotics, an investigation was performed on bacteria isolated from water and sediment collected along the Pasvik River course during two surveys (May and July). Bacterial strains were screened for their biofilm production and profiles of susceptibility to antibiotics. Results showed that biofilm formation was a widespread characteristic of the isolates. Most of them were also resistant to several antibiotics, such as ampicillin (100% of the isolates) as well as cefazolin, cefoxitin, ceftriaxone, mezlocillin, nitrofurantoin and sisomicin (90% of the total strains). This study shows a significant association between biofilm formation and antibiotic resistance at inner stations both in water and in sediments in May only. This suggests that in Pasvik River colder temperature may stimulate bacterial aggregation into biofilm and simultaneously decrease bacterial susceptibility to antibiotics; since the occurrence of antibiotic resistance has frequently been linked to the presence of pollutants, this result could represent a strategy of bacterial survival under altered environmental conditions.

Use and Overuse of Food Additives in Edible Products: Health Consequences for Consumers

The aim of this chapter was to address the issue of uses and overuses of additives with consequent impacts on human health. Modern food additives have an important role in food production. At present, the number of individuals engaged in food primary production is dramatically decreasing; on the other hand, consumers seems to search for many food choices, including ready-to-eat foods, with annexed higher safety and hygiene standards (and food additives may be a concern). The most part of consumers have still confidence in the work of official commissions in defense of food safety; on the other hand, some people may find deem discrepancies between their own sense of security and the complex of laws or practices in defense of the human health. Main worries concern the enormous economic power of certain multinational groups in the field of food production; the absolute discretion of Committees to judge eligible or not eligible available researches on certain food additives; the choice of research methods and the lack of studies concerning synergist effects of different food additives.