Occurrence and dynamics of potentially pathogenic vibrios in the wet-dry tropics of northern Australia

Bacteria from the Vibrio genus are a ubiquitous component of coastal and estuarine ecosystems with several pathogenic Vibrio species displaying preferences for warm tropical waters. We studied the spatial and temporal abundance of three key human potential pathogens V. parahaemolyticus, V. cholerae and V. vulnificus in northern tropical Australia, over the wet and dry seasons, to identify environmental parameters influencing their abundance. Quantitative PCR (qPCR) analysis revealed that V. parahaemolyticus occurred more frequently and in higher abundance than V. cholerae and V. vulnificus across all locations examined. All three species were more abundant during the wet season, with V. parahaemolyticus abundance correlated to temperature and conductivity, whereas nutrient concentrations and turbidity best explained V. vulnificus abundance. In addition to these targeted qPCR analyses, we assessed the composition and dynamics of the entire Vibrio community using hsp60 amplicon sequencing. Using this approach, 42 Vibrio species were identified, including a number of other pathogenic species such as V. alginolyticus, V. mimicus and V. fluvialis. The Vibrio community was more diverse in the wet season, with temperature and dissolved oxygen as the key factors governing community composition. Seasonal differences were primarily driven by a greater abundance of V. parahaemolyticus and V. vulnificus during the wet season, while spatial differences were driven by different abundances of V. harveyi, V. campbellii, V. cholerae and V. navarrensis. When we related the abundance of Vibrio to other bacterial taxa, defined using 16S rRNA gene amplicon sequencing, V. parahaemolyticus was negatively correlated to several taxa, including members of the Rickettsiales and Saccharimonadales, while V. vulnificus was negatively correlated to Rhobacteriaceae and Cyanobiaceae. In contrast, V. alginolyticus, V. harveyi and V. mediterranei were all positively correlated to Cyanobacteria. These observations highlight the dynamic nature of Vibrio communities and expands current understanding of the processes governing the occurrence of potentially pathogenic Vibrio spp. in tropical coastal ecosystems

Pearl Oyster Bacterial Community Structure Is Governed by Location and Tissue-Type, but Vibrio Species Are Shared Among Oyster Tissues.

Diseases of bivalves of aquacultural importance, including the valuable Australian silver-lipped pearl oyster (Pinctada maxima), have been increasing in frequency and severity. The bivalve microbiome is linked to health and disease dynamics, particularly in oysters, with putative pathogens within the Vibrio genus commonly implicated in oyster diseases. Previous studies have been biased toward the Pacific oyster because of its global dominance in oyster aquaculture, while much less is known about the microbiome of P. maxima. We sought to address this knowledge gap by characterizing the P. maxima bacterial community, and we hypothesized that bacterial community composition, and specifically the occurrence of Vibrio, will vary according to the sampled microenvironment. We also predicted that the inside shell swab bacterial composition could represent a source of microbial spillover biofilm into the solid pearl oyster tissues, thus providing a useful predictive sampling environment. We found that there was significant heterogeneity in bacterial composition between different pearl oyster tissues, which is consistent with patterns reported in other bivalve species and supports the hypothesis that each tissue type represents a unique microenvironment for bacterial colonization. We suggest that, based on the strong effect of tissue-type on the pearl oyster bacterial community, future studies should apply caution when attempting to compare microbial patterns from different locations, and when searching for disease agents. The lack of association with water at each farm also supported the unique nature of the microbial communities in oyster tissues. In contrast to the whole bacterial community, there was no significant difference in the Vibrio community among tissue types nor location. These results suggest that Vibrio species are shared among different pearl oyster tissues. In particular, the similarity between the haemolymph, inside shell and solid tissues, suggests that the haemolymph and inside shell environment is a source of microbial spillover into the oyster tissues, and a potentially useful tool for non-destructive routine disease testing and early warning surveillance. These data provide important foundational information for future studies identifying the factors that drive microbial assembly in a valuable aquaculture species

Removal of reactive black 5 dye from aqueous solutions by Fe3O4@SiO2-APTES nanoparticles

In this study, Fe3O4@SiO2-APTES nanoparticles were successfully synthesized via a one-pot route in order to remove reactive black 5 dye from aqueous solutions. To obtain optimal conditions on the dye removal efficiency, the effects of various parameters were investigated including solution pH, initial dye concentration, and absorbent dosage. According to the experimental results, the removal efficiency of the dye decreased with increasing in pH and initial dye concentration, as well as with decreased adsorbent dosage. In fact, about 100.00 % of reactive black 5 was removed from aqueous solution using Fe3O4@SiO2-APTES NPs at the adsorbent amount of 0.4 g L^-1 and pH = 3 in 90 min. The kinetics were found well match with pseudo-second-order equation. The isotherm analysis indicated that the equilibrium data were well fitted to the Langmuir isotherm model, showing a monolayer adsorption manner of the dyes on homogeneous surface of nanoparticles. Also, the results of absorbent recycling showed that this nanoparticle could be reused up to 6 times with high efficiency

Photocatalytic degradation of Metronidazole with illuminated TiO<inf>2</inf> nanoparticles

Metronidazole (MNZ) is a brand of nitroimidazole antibiotic, which is generally used in clinical applications and extensively used for the treatment of infectious diseases caused by anaerobic bacteria and protozoans. The aim of this investigation was to degrade MNZ with illuminated TiO2 nanoparticles at different catalyst dosage, contact time, pH, initial MNZ concentration and lamp intensity. Maximum removal of MNZ was observed at near neutral pH. Removal efficiency was decreased by increasing dosage and initial MNZ concentration. The reaction rate constant (kobs) was decreased from 0.0513 to 0.0072 min−1 and the value of electrical energy per order (EEo) was increased from 93.57 to 666.67 (kWh/m3 ) with increasing initial MNZ concentration from 40 to 120 mg/L, respectively. The biodegradability estimated from the BOD5/COD ratio was increased from 0 to 0.098. The photocatalyst demonstrated proper photocatalytic activity even after five successive cycles. Finally, UV/TiO2 is identified as a promising technique for the removal of antibiotic with high efficiency in a relatively short reaction time

Harcèlement et abus (violence non accidentelle) dans le sport : synthèse ReFORM de la position de consensus du Comité International Olympique

editorial reviewe

Optimization of dimethyl phthalate degradation parameters using zero-valent iron nanoparticles by response surface methodology: Determination of degradation intermediate products and process pathway

Background and purpose: Phthalic acid esters (PAEs) are a group of organic compounds that are used as additives in plastic industry. Among PAEs, dimethyl phthalate (DMP), the simplest compound in phthalates, is an aromatic pollutant that disturbs endocrine function. The aim of this study was to assess the effect of zero-valent iron nanoparticles (NZVI) on the DMP degradation. Materials and methods: NZVI were prepared by reduction of ferric chloride using sodium borohydride. Physical properties of nanoparticles were determined using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), and Vibrating Sample Magnetometer (VSM). Then, the effect of pH, DMP concentrations, the amount of NZVI, and contact time were investigated on DMP removal efficiency. Response surface methodology based on Box- Behnken was used to study the interaction between variables. Results: Maximum efficiency (99) of DMP removal by NZVI was achieved in optimum conditions (pH=3, NZVI dosage =0.6 g/l, DMP concentration = 2 mg/l, and contact time= 65 min). The Box-Behnken analysis confirmed that pH and NZVI dosage have had the highest and lowest effect in the process of DMP removal by NZVI, respectively. Conclusion: According to findings, NZVI in small amounts have a proper efficiency in DMP removal. Also, DMP degradation efficiency did not change much, after being used in five consecutive cycles of degradation reactions. This shows a potential application prospect of the synthesized NZVI in real water treatment. © 2015 Journal of Mazandaran University of Medical Sciences. All Rights Reserved

Optimization of dimethyl phthalate degradation parameters using zero-valent iron nanoparticles by response surface methodology: Determination of degradation intermediate products and process pathway

Background and purpose: Phthalic acid esters (PAEs) are a group of organic compounds that are used as additives in plastic industry. Among PAEs, dimethyl phthalate (DMP), the simplest compound in phthalates, is an aromatic pollutant that disturbs endocrine function. The aim of this study was to assess the effect of zero-valent iron nanoparticles (NZVI) on the DMP degradation. Materials and methods: NZVI were prepared by reduction of ferric chloride using sodium borohydride. Physical properties of nanoparticles were determined using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), and Vibrating Sample Magnetometer (VSM). Then, the effect of pH, DMP concentrations, the amount of NZVI, and contact time were investigated on DMP removal efficiency. Response surface methodology based on Box- Behnken was used to study the interaction between variables. Results: Maximum efficiency (99) of DMP removal by NZVI was achieved in optimum conditions (pH=3, NZVI dosage =0.6 g/l, DMP concentration = 2 mg/l, and contact time= 65 min). The Box-Behnken analysis confirmed that pH and NZVI dosage have had the highest and lowest effect in the process of DMP removal by NZVI, respectively. Conclusion: According to findings, NZVI in small amounts have a proper efficiency in DMP removal. Also, DMP degradation efficiency did not change much, after being used in five consecutive cycles of degradation reactions. This shows a potential application prospect of the synthesized NZVI in real water treatment. © 2015 Journal of Mazandaran University of Medical Sciences. All Rights Reserved

Prevalence of echinococcosis in humans, livestock and dogs in northern Italy

AbstractThe presence of Echinococcus sp. cysts was investigated in 822 sheep, 123 goats and 112,521 cattle from Lombardy region, North Italy. Faecal samples from 40 sheepdogs were also analyzed, with 9 samples containing taeniid eggs (22.5 %), 8 samples being coproantigen-positive (20 %), and one dog from a northern province (Lecco) positively confirmed by PCR. Cystic Echinococcosis (CE) was detected in 0.36 % of sheep and in 0.29 % of cattle in 2004. No goat resulted to be infected. Data from CE patients treated in Lombardy were collected by inspecting hospital discharge records. In 2004, 156 CE-related admissions (62 % male and 38 % female) were reported in Lombardy. Total hospital stay was 1,372 days (1,286 for inpatients, 86 for outpatients). Most patients (72.4 %) were residents in Lombardy and 1.9 % were from Piedmont; the remaining patients were from central and southern Italy. According to acquired data CE resulted hypoendemic in animals in Lombardy. Prevalence rates in humans were higher than expected in this region, usually considered as non-endemic. Assessment of the prevalence of CE in humans remains a difficult, costly, time-consuming and labourintensive task. The present study suggests establishing a National Registry of Cystic Echinococcosis with the aim to highlight regional risk factors and to benefit from its matching both clinical and epidemiological data

Salvage therapy with high dose Intravenous Immunoglobulins in acquired Von Willebrand Syndrome and unresponsive severe intestinal bleeding

A 91-year-old woman affected with acquired Von Willebrand (VW) syndrome and intestinal angiodysplasias presented with severe gastrointestinal bleeding (hemoglobin 5\ua0g/dl). Despite replacement therapy with VW factor/factor VIII concentrate qid, bleeding did not stop (eleven packed red blood cell units were transfused over three days). High circulating levels of anti-VW factor immunoglobulin M were documented immunoenzimatically. Heart ultrasound showed abnormalities of the mitral and aortic valves with severe flow alterations. When intravenous immunoglobulins were added to therapy, prompt clinical and laboratory responses occurred: complete cessation of bleeding, raise in hemoglobin, VW factor antigen, VW ristocetin cofactor and factor VIII levels as well as progressive reduction of the anti-VWF autoantibody levels