Virulence associated factors in bacteria from water bodies in Belem, Para, Brazil: bacteriological composition and threat to public health

Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Microbiologia Ambiental. Ananindeua, PA, Brasil.Federal University of Pará. Belém, PA, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Microbiologia Ambiental. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Microbiologia Ambiental. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Microbiologia Ambiental. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Biologia Molecular. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Laboratório de Microbiologia Ambiental. Ananindeua, PA, Brasil.A lack of sewage treatment contaminates water bodies threatening human health by spreading waterborne gastroenteritis. This is a particular problem for developing countries, where the risks associated with surface water contamination remain largely unknown. To understand the risk associated with sewage contamination of water bodies, we evaluated the microbiological indicators of water quality and isolated bacterial strains from water bodies from the city of Belém, Pará, Brazil. The strains were identified by biochemical and serological tests and polymerase chain reactions (PCRs). The thermotolerant coliforms and Escherichia coli presented values above 1,000 (NMP/ 100 mL) biweekly from August 2012 to November 2015, without a significant statistical difference between sampling periods (Kruskal–Wallis p > 0.05). The water of the Tucunduba river presented contamination levels similar to those in a sewage pumping station (Dunn test p > 0.05). From 240 bacterial isolates, we identified 163 Vibrio cholerae, 8 Vibrio mimicus, 24 E. coli, and 5 Salmonella spp. The isolates of V. cholerae demonstrated N-acetylglucosamine (NAG) profile (Non-O1 and NonO139) and 18 expressed the stn/sto gene. No E. coli was shown to be potentially pathogenic. The results revealed that water bodies in Belém were constantly contaminated by sewage and fecal microorganisms, including the potential circulation of pathogens in viable and cultivable form

Population and Genetic Study of <i>Vibrio cholerae</i> from the Amazon Environment Confirms that the <i>WASA-1</i> Prophage Is the Main Marker of the Epidemic Strain that Circulated in the Region

<div><p><i>Vibrio cholerae</i> is a natural inhabitant of many aquatic environments in the world. Biotypes harboring similar virulence-related gene clusters are the causative agents of epidemic cholera, but the majority of strains are harmless to humans. Since 1971, environmental surveillance for potentially pathogenic <i>V. cholerae</i> has resulted in the isolation of many strains from the Brazilian Amazon aquatic ecosystem. Most of these strains are from the non-O1/non-O139 serogroups (NAGs), but toxigenic O1 strains were isolated during the Latin America cholera epidemic in the region (1991-1996). A collection of environmental <i>V. cholerae</i> strains from the Brazilian Amazon belonging to pre-epidemic (1977-1990), epidemic (1991-1996), and post-epidemic (1996-2007) periods in the region, was analyzed. The presence of genes related to virulence within the species and the genetic relationship among the strains were studied. These variables and the information available concerning the strains were used to build a Bayesian multivariate dependency model to distinguish the importance of each variable in determining the others. Some genes related to the epidemic strains were found in environmental NAGs during and after the epidemic. Significant diversity among the virulence-related gene content was observed among O1 strains isolated from the environment during the epidemic period, but not from clinical isolates, which were analyzed as controls. Despite this diversity, these strains exhibited similar PFGE profiles. PFGE profiles were significant while separating potentially epidemic clones from indigenous strains. No significant correlation with isolation source, place or period was observed. The presence of the <i>WASA-1</i> prophage significantly correlated with serogroups, PFGE profiles, and the presence of virulence-related genes. This study provides a broad characterization of the environmental <i>V. cholerae</i> population from the Amazon, and also highlights the importance of identifying precisely defined genetic markers such as the <i>WASA-1</i> prophage for the surveillance of cholera.</p> </div

Distribution of genotypes among NAG strains.

<p>The presence or absence of virulence-related genes are represented, respectively, by blue and white squares. The histogram below each figure correspond to the frequency of each gene. The colors highlighting the strains’ keys correspond to the isolation sources. Strains highlighted pink were isolated from wastewater, blue from superficial water, green from superficial stream water, yellow from fish, and brown from copepods.</p

Geographical distribution of <i>V. cholerae</i> isolates.

<p>The geographical location of rivers, streams, and wastewater plants from where the strains that were used in this study were isolated are indicated in the map. The sizes of markers indicate the number of strains in each location, markers are centered in the cities where the strains were isolated (see Table S1). Belem (yellow), Barcarena (light green), Maruda (pink), Macapá (dark green), Oiapoque (light blue), Manaus (red), Tabatinga (light blue), Rio Branco (purple), and Santa Rosa (orange). Quantities of strains isolated in each period are indicated in the bar graphs. </p

Dependency model of multivariate data from strains.

<p>Bayesian network representing conditional probabilities of variables that were available for the strains. Arcs are colored according to the impact in the posterior probability of the model when the arc is removed. The network represents the end result of the evaluation of 4.5 * 10⁷ different topologies, in which the last 1.4 * 10⁷ evaluations did not yield a better model. The network was constructed using the online B-Course software [42]. </p

O1 genotypes.

<p>The presence and absence of virulence-related genes are represented, respectively, by blue and white squares. The strains are grouped in colored bars according to their PFGE cluster (Fig. 4): from top to bottom are groups 1 (purple), 2 (red), 3 (blue), 9 (yellow), 6 (orange), and 8 (green). The colors highlighting the strain keys correspond to the isolation sources. Strains highlighted pink were isolated from wastewater, blue from superficial water, green from superficial stream water, and black from clinical sources.</p

Lycopene from Red Guava (<i>Psidium guajava</i> L.): From Hepatoprotective Effect to Its Use as Promising Self-Emulsifying Drug Delivery System for Anti-Inflammatory and Antioxidant Applications

Lycopene is a carotenoid with potential use in the treatment of chronic illnesses. Here, different formulations of lycopene were studied: lycopene-rich extract from red guava (LEG), purified lycopene from red guava (LPG) and a self-emulsifying drug delivery system loaded with LPG (nanoLPG). The effects of administering orally various doses of LEG to hypercholesterolemic hamsters were evaluated regarding the liver function of the animals. The cytotoxicity of LPG in Vero cells was analyzed by a crystal violet assay and by fluorescence microscopy. In addition, nanoLPG was employed in stability tests. LPG and nanoLPG were tested for their cytotoxic effect on human keratinocytes and antioxidant capacity on cells in an endothelial dysfunction model in an isolated rat aorta. Finally, the effect of different nanoLPG concentrations on the expression of immune-related genes (IL-10, TNF-α, COX-2 and IFN-γ) from peripheral blood mononuclear cells (PBMC) using real-time PCR was also analyzed. Results suggest that LEG, despite not being able to improve blood markers indicative of liver function in hypercholesterolemic hamsters, reduced hepatic degenerative changes. Additionally, LPG did not show cytotoxicity in Vero cells. In relation to nanoLPG, the effects produced by heat stress evaluated by Dynamics Light Scattering (DLS) and visually were loss of color, texture change and phase separation after 15 days without interfering with the droplet size, so the formulation proved to be efficient in stabilizing the encapsulated lycopene. Although LPG and nanoLPG showed moderate toxicity to keratinocytes, which may be related to cell lineage characteristics, both revealed potent antioxidant activity. LPG and nanoLPG showed vasoprotective effects in aortic preparations. The gene expression assay indicates that, although no significant differences were observed in the expression of IL-10 and TNF-α, the PBMCs treated with nanoLPG showed a reduction in transcriptional levels of IFN-γ and an increased expression of COX-2. Thus, the work adds evidence to the safety of the use of lycopene by humans and shows that tested formulations, mainly nanoLPG due to its stability, stand out as promising and biosafe products for the treatment of diseases that have oxidative stress and inflammation in their etiopathology