Structure and fate of a Pseudomonas aeruginosa population originating from a combined sewer and colonizing a wastewater treatment lagoon

The efficacy of a wastewater treatment lagoon (WWTL) at preventing the spread of Pseudomonas aeruginosa into natural aquatic habitats was investigated. A WWTL and its connected combined sewer and brook were exhaustively sampled. Physico-chemical analyses showed a stratification of the first pond according to pH, temperature and oxygen content. The P. aeruginosa counts partially matched this stratification with higher values among the bottom anaerobic waters of the first half of this pond. Genotyping of 494 WWTL P. aeruginosa strains was performed and led to the definition of 85 lineages. Dominant lineages were observed, with some being found all over the WWTL including the connected brook. IS5 was used as an indicator of genomic changes, and 1 to 12 elements were detected among 16 % of the strains. IS-driven lasR (genetic regulator) disruptions were detected among nine strains that were not part of the dominant lineages. These insertional mutants did not show significant elastase activities but showed better growth than the PAO1 reference strain in WWTL waters. Differences in growth patterns were related to a better survival of these mutants at an alkaline pH and a better ability at using some C-sources such as alanine. The opportunistic colonization of a WWTL by P. aeruginosa can involve several metabolic strategies which appeared lineage specific. Some clones appeared more successful than others at disseminating from a combined sewer toward the overflow of a WWTL.     

Treatment of Basic Red 29 dye solution using iron-aluminum electrode pairs by electrocoagulation and electro-Fenton methods

The aim of this study is the treatment of Basic Red 29 (BR29) dye solution using hybrid iron-aluminum electrodes by electrocoagulation and electro-Fenton methods. The effect of current density, initial pH, supporting electrolyte, H₂O₂, and initial dye concentration on dye removal efficiency was investigated, and the best experimental conditions were obtained. Time-coarse variation of UV-Vis spectra and toxicity and chemical oxygen demand (COD) removal were also examined at the best experimental conditions. Both systems were found very successful for the removal of BR29 dye. The removal efficiency of >95 % for BR29 dye solution was reached easily in a short time. At the best experimental conditions, for the initial BR29 concentration of 100 mg/L, >95 % BR29 dye and 71.43 % COD removal were obtained after 20 and 40 min of electrolysis, respectively. Additionally, toxicity results for electro-Fenton treatment of 100 mg/L BR29 were also very promising. According to the results obtained, although electro-Fenton is more effective, both systems can be used successfully to treat textile wastewater including dyes.     

Concentrations, distributions, and sources of polychlorinated biphenyls and polycyclic aromatic hydrocarbons in bed sediments of the water reservoirs in Slovakia

Dredging water reservoirs is necessary to maintain accumulation capacity and to prevent floodings. As a first step, the quality of the bed sediments in water reservoirs must be determined before dredging operations. In this study, sediment samples from 34 stations of three selected water reservoirs (Zemplinska Sirava, Velke Kozmalovce, and Ruzin) were collected to investigate concentrations, distributions, and hazards of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) and to predict their possible sources. Total PCB concentrations were in the range of 20.4 to 2,325?ng/g. The maximum concentrations of PCBs were found in sediments from Zemplinska Sirava, which is in the vicinity of a former manufacturer of PCBs. The composition of PCBs was characterized by tri- and hexa-CB congeners, indicating the influence of contamination from the use of specific Delor mixtures, formerly produced and massively used on the territory of Slovakia. The data showed that the highest total PAH concentrations were associated with the sediments from the Velke Kozmalovce, ranging from 7,910 to 29,538?ng/g. On the other hand, the lowest total PAH concentrations (84?C631?ng/g of dry weight) were found in the sediments of Zemplinska Sirava, an important recreational area in eastern Slovakia. The distribution of individual PAHs was similar among the three water reservoirs, and this, together with principal component analysis and diagnostic PAH ratios, suggests mainly pyrolytic contamination of the sediments. However, petrogenic inputs appear to be important in the Zemplinska Sirava sediments.     

A 1-Year Study on the Detection of Human Enteric Viruses in New Caledonia

Human enteric viruses occur in high concentrations in wastewater and can contaminate receiving environmental waters. Due to the lack of data on the prevalence of enteric viruses in New Caledonia, the presence and the concentrations of enteric viruses in wastewater and seawater were determined. Untreated wastewater and seawater samples were collected monthly for 1 year from a wastewater treatment plant (WWTP) and from the WWTP’s outlet, located directly on a popular recreational beach. Samples were tested for norovirus genogroups I and II (NoV GI and GII), astroviruses (AsV), sapoviruses (SaV), enteroviruses (EV), hepatitis A viruses (HAV), rotaviruses (RoV), human adenoviruses (HAdV) and human polyomaviruses (HPyV). To support these data, faecal samples from cases of gastroenteritis were tested for the first time for NoV and detected in the population. NoV GI, NoV GII, EV, SaV, HAdV and HPyV were detected in all wastewaters, RoV in 75 % and AsV in 67 %. HAV were not detected in wastewater. Overall, 92 % of seawater samples were positive for at least one virus. HPyV were detected most frequently in 92 % of samples and at concentrations up to 7.7 × 10³ genome copies/L. NoV GI, NoV GII, EV, SaV, RoV and HAdV were found in 33, 66, 41, 33, 16 and 66 % of seawater samples, respectively. AsV were not detected in seawater. This study reports for the first time the presence of NoV and other enteric viruses in New Caledonia and highlights the year-round presence of enteric viruses in the seawater of a popular beach.     

Negative correlation between nuptial throat colour and blood parasite load in male European green lizards supports the Hamilton–Zuk hypothesis

During female mate choice, conspicuous male sexual signals are used to infer male quality and choose the best sire for the offspring. The theory of parasite-mediated sexual selection (Hamilton–Zuk hypothesis) presumes that parasite infection can influence the elaboration of sexual signals: resistant individuals can invest more energy into signal expression and thus advertise their individual quality through signal intensity. By preferring these males, females can provide resistance genes for their offspring. Previous research showed that nuptial throat colour of male European green lizard, Lacerta viridis, plays a role in both inter- and intrasexual selections as a condition-dependent multiple signalling system. The aim of this study was to test the predictions of the Hamilton–Zuk hypothesis on male European green lizards. By blood sampling 30 adult males during the reproductive season, we found members of the Haemogregarinidae family in all but one individual (prevalence?=?96 %). The infection intensity showed strong negative correlation with the throat and belly colour brightness in line with the predictions of the Hamilton–Zuk hypothesis. In addition, we found other correlations between infection intensity and other fitness-related traits, suggesting that parasite load has a remarkable effect on individual fitness. This study shows that throat patch colour of the European green lizards not only is a multiple signalling system but also possibly acts as an honest sexual signal of health state in accordance with the Hamilton–Zuk hypothesis.     

Discordant non-invasive prenatal testing (NIPT) – a systematic review

With a high sensitivity and specificity, non-invasive prenatal testing (NIPT) is an incomparable screening test for fetal aneuploidy. However, the method is rather newly introduced, and experiences with discordant results are few. We did a systematic review of literature reporting details of false positive and false negative NIPT results. Discordant sex chromosome results were not included. We identified 22 studies reporting case details. In total, 206 discordant cases were included, of which 88% were false positive and 12% false negative. Details on maternal age, gestational age, platform/company, Z-score, fetal fraction, results and explanation were specified. The main reasons for discordant results were confined placental mosaicism, maternal copy number variation, vanished twin, maternal cancer and true fetal mosaicism. A very high percentage of cases (67%) were reported with no obvious biological or technical explanation for the discordant result. The included cases represent only a minor part of the true number of false positive or false negative NIPT cases identified in fetal medicine clinics around the world. To ensure knowledge exchange and transparency of NIPT between laboratories, we suggest a systematic recording of discordant NIPT results, as well as a quality assurance by external quality control and accreditation. © 2017 John Wiley & Sons, Ltd.     

Fetal cerebral hemorrhage due to X-linked GATA1 gene mutation

We report a multiplex family with a GATA1 gene mutation responsible for a massive fetal cerebral hemorrhage occurring at 36 weeks. Two other stillbirth cousins presented with fetal hydrops and congenital hemochromatosis' phenotype at 37 and 12 weeks of gestation. Molecular screening revealed the presence of a c.613G>A pathogenic allelic variation in exon 4 of GATA1 gene in the 3 male siblings and their carrier mothers. The diagnosis of a GATA1 gene mutation may be suspected in cases of male fetuses with intracerebral bleeding, particularly if a history of prior fetal loss(es) and mild maternal thrombocytopenia are also present.     

Occurrence and Trend of Hepatitis A Virus in Bivalve Molluscs Production Areas Following a Contamination Event

The aim of this study was to assess the trend of hepatitis A virus (HAV) in a coastal zone impacted by a contamination event, providing data for the development of management strategies. A total of 352 samples, including four bivalve mollusc species (Mytilus galloprovincialis, Solen vagina, Venus gallina and Donax trunculus), were taken over a period of 6 months from 27 production areas of the coast and analysis were performed according to ISO/TS 15216-1:2013. HAV presence was detected in 77 samples from 11 production areas and all positive results were related to samples collected in the first 3 months of the surveillance, during which HAV prevalence was 39.9% and values as high as 5096 genome copies/g were detected. A progressive reduction of viral contamination was evident during the first trimester of the monitoring, with prevalence decreasing from 78.8% in the first month, to 37.8% in the second and 3.9% in the third and quantitative levels reduced from an average value of 672 genome copies/g to 255 genome copies/g over a period of 4 weeks (virus half-life: 21.5 days). A regression analysis showed that, during the decreasing phase of the contamination, the data fitted a reciprocal quadratic model (Ra² = 0.921) and, based on the model, a residual presence of HAV could be estimated after negativization of the production areas. The statistical analysis of the results per shellfish species and per production area showed that there were limited differences in contamination prevalence and levels among diverse bivalve species, while a statistically significant difference was present in quantitative levels of one production area. These data could be useful for the development of both risk assessment models and code of practice for the management of viral contamination in primary production.