Pharmaceuticals and endocrine disrupting compounds modulate adverse effects of climate change on resource quality in freshwater food webs.

Freshwater biodiversity, ecosystem functions and services are changing at an unprecedented rate due to the impacts of vast number of stressors overlapping in time and space. Our study aimed at characterizing individual and combined impacts of pollution with pharmaceuticals (PhACs) and endocrine disrupting compounds (EDCs) and increased water temperature (as a proxy for climate change) on primary producers and first level consumers in freshwaters. We conducted a microcosm experiment with a simplified freshwater food web containing moss (Bryophyta) and shredding caddisfly larvae of Micropterna nycterobia (Trichoptera). The experiment was conducted with four treatments; control (C), increased water temperature + 4 °C (T2), emerging contaminants' mix (EC = 15 PhACs & 5 EDCs), and multiple stressor treatment (MS = EC + T2). Moss exhibited an overall mild response to selected stressors and their combination. Higher water temperature negatively affected development of M. nycterobia through causing earlier emergence of adults and changes in their lipidome profiles. Pollution with PhACs and EDCs had higher impact on metabolism of all life stages of M. nycterobia than warming. Multiple stressor effect was recorded in M. nycterobia adults in metabolic response, lipidome profiles and as a decrease in total lipid content. Sex specific response to stressor effects was observed in adults, with impacts on metabolome generally more pronounced in females, and on lipidome in males. Thus, our study highlights the variability of both single and multiple stressor impacts on different traits, different life stages and sexes of a single insect species. Furthermore, our research suggests that the combined impacts of warming, linked to climate change, and contamination with PhACs and EDCs could have adverse consequences on the population dynamics of aquatic insects. Additionally, these findings point to a potential decrease in the quality of resources available for both aquatic and potentially terrestrial food webs.

Effects of combining flow intermittency and exposure to emerging contaminants on the composition and metabolic response of streambed biofilm bacterial communities.

Freshwater ecosystems are characterised by the co-occurrence of stressors that simultaneously affect the biota. Among these, flow intermittency and chemical pollution severely impair the diversity and functioning of streambed bacterial communities. Using an artificial streams mesocosm facility, this study examined how desiccation and pollution caused by emerging contaminants affect the composition of stream biofilm bacterial communities, their metabolic profiles, and interactions with their environment. Through an integrative analysis of the composition of biofilm communities, characterization of their metabolome and composition of the dissolved organic matter, we found strong genotype-to-phenotype interconnections. The strongest correlation was found between the composition and metabolism of the bacterial community, both of which were influenced by incubation time and desiccation. Unexpectedly, no effect of the emerging contaminants was observed, which was due to the low concentration of the emerging contaminants and the dominant impact of desiccation. However, biofilm bacterial communities modified the chemical composition of their environment under the effect of pollution. Considering the tentatively identified classes of metabolites, we hypothesised that the biofilm response to desiccation was mainly intracellular while the response to chemical pollution was extracellular. The present study demonstrates that metabolite and dissolved organic matter profiling may be effectively integrated with compositional analysis of stream biofilm communities to yield a more complete picture of changes in response to stressors.

Fate and effects of microplastics in combination with pharmaceuticals and endocrine disruptors in freshwaters: Insights from a microcosm experiment.

Microplastic contamination of freshwater ecosystems has become an increasing environmental concern. To advance the hazard assessment of microplastics, we conducted a microcosm experiment in which we exposed a simplified aquatic ecosystem consisting of moss and caddisflies to microplastics (polyethylene, polystyrene and polypropylene) and pharmaceuticals and personal care products (1H-benzotriazole, bisphenol A, caffeine, gemfibrozil, ketoprofen, methylparaben, estriol, diphenhydramine, tris (1-chloro-2-propyl) phosphate) over the course of 60 days. We monitored the flux of microplastics within the microcosm, as well as the metabolic and total protein variation of organisms. This study offers evidence highlighting the capacity of moss to act as a sink for free-floating microplastics in freshwater environments. Moss is also shown to serve as a source and pathway for microplastic particles to enter aquatic food webs via caddisflies feeding off of the moss. Although most ingested microparticles were eliminated between caddisflies life stages, a small fraction of microplastics was transferred from aquatic to terrestrial ecosystem by emergence. While moss exhibited a mild response to microplastic stress, caddisflies ingesting microplastics showed stress comparable to that caused by exposure to pharmaceuticals. The molecular responses that the stressors triggered were tentatively identified and related to phenotypic responses, such as the delayed development manifested through the delayed emergence of caddisflies exposed to stress. Overall, our study provides valuable insights into the adverse effects of microplastics on aquatic species, compares the impacts of microplastics on freshwater biota to those of pharmaceuticals and endocrine disrupting compounds, and demonstrates the role aquatic organisms have in redistributing microplastics between aquatic and terrestrial ecosystems.

Characterisation and toxicological activity of three different Pseudo-nitzschia species from the northern Adriatic Sea (Croatia).

Diatoms of the genus Pseudo-nitzschia are cosmopolitans spread in seas and oceans worldwide, with more than 50 described species, dozens of which have been confirmed to produce domoic acid (DA). Here, we characterized and investigated the toxicological activity of secondary metabolites excreted into the growth media of different Pseudo-nitzschia species sampled at various locations in the northern Adriatic Sea (Croatia) using human blood cells under in vitro conditions. The results revealed that three investigated species of the genus Pseudo-nitzschia were capable of producing DA indicating their toxic potential. Moreover, toxicological data suggested all three Pseudo-nitzschia species can excrete toxic secondary metabolites into the surrounding media in addition to the intracellular pools of DA, raising concerns regarding their toxicity and environmental impact. In addition, all three Pseudo-nitzchia species triggered oxidative stress, one of the mechanisms of action likely responsible for the DNA damage observed in human blood cells. In line with the above stated, our results are of great interest to environmental toxicologists, the public and policy makers, especially in light of today's climate change, which favours harmful algal blooms and the growth of DA producers with a presumed negative impact on the public health of coastal residents.

Bioaccumulation and bioamplification of pharmaceuticals and endocrine disruptors in aquatic insects.

Environmental fate of emerging contaminants such as pharmaceuticals and endocrine disrupting compounds at the aquatic terrestrial boundary are largely unexplored. Aquatic insects connect aquatic and terrestrial food webs as their life cycle includes aquatic and terrestrial life stages, thus they represent an important inter-habitat linkage not only for energy and nutrient flow, but also for contaminant transfer to terrestrial environments. We measured the concentrations of pharmaceuticals and endocrine disrupting compounds in the larval and adult tissues (last larval stages and teneral adults) of five Odonata species sampled in a wastewater-impacted river, in order to examine their bioaccumulation and bioamplification at different taxonomic levels. Twenty different compounds were bioaccumulated in insect tissues, with majority having higher concentrations (up to 90% higher) in aquatic larvae compared to terrestrial adults (reaching 88 ng/g for 1H-benzotriazole). However, increased concentration in adults was observed for seven compounds in at least one suborder (41% of the accumulated), confirming contaminants bioamplification across the metamorphosis. Both, bioaccumulation and bioamplification differed at various taxa levels; the order (Odonata), suborder (Anisoptera and Zygoptera) and species level. Highest variability was observed between Anisoptera and Zygoptera, due to the underlying differences in their ecology. Generally, Zygoptera had higher concentrations of contaminants in both larvae and adults. Additionally, we aimed at predicting effects of contaminant properties on bioaccumulation and bioamplification patterns using the commonly used physicochemical and pharmacokinetic descriptors on both order and suborder levels, however, neither of the two processes could be consistently predicted with simple linear models. Our study highlights the importance of taxonomy in studies aiming at advancing the understanding of contaminant exchange between aquatic and terrestrial food webs, as higher taxonomic categories include ecologically diverse groups, whose contribution to "the dark side of subsidies" could substantially differ.

Salivary Scca1, Scca2 and Trop2 in Oral Cancer Patients-A Cross-Sectional Pilot Study.

Oral squamous cell carcinoma (OSCC) is frequently diagnosed in the advanced stages. The purpose of this paper is to determine the salivary values of SCCA1, SCCA2 and TROP2 in patients with T1N0M0 OSCC and to compare them with the values obtained from healthy individuals. Unstimulated (UWS) and stimulated (SWS) saliva was sampled from 29 patients with T1N0M0 OSCC and 29 sex- and age-matched healthy individuals. Statistical difference was observed in SCCA1 and SCCA2 levels both in UWS and SWS samples. TROP2 was not measurable in most of the salivary samples. Both SCCA1 and SCCA2 could represent potential biomarkers for the early-stage OSCC. Research on a larger sample and biomarker validation is needed to assess the clinical potential of SCCA1 and SCCA2 in the OSCC early diagnostics.

The curious case of methylparaben: Anthropogenic contaminant or natural origin?

The widespread use of methylparaben as a preservative has caused increased exposure to natural aquatic systems in recent decades. However, current studies have suggested that exposure to this compound can result in endocrine disrupting effects, raising much concern regarding its environmental impact. In contast, methylparaben has also been found to be part of the metabolome of some organisms, prompting the question as to whether this compound may be more natural than previously assumed. Through a combination of field studies investigating the natural presence of methylparaben across different taxa, and a 54-day microcosm experiment examining the bioaccumulation and movement of methylparaben across different life stages of aquatic insects (order Trichoptera), our results offer evidence suggesting the natural origin of methylparaben in aquatic and terrestrial biota. This study improves our understanding of the role and impact this compound has on biota and challenges the current paradigm that methylparaben is exclusively a harmful anthropogenic contaminant. Our findings highlight the need for further research on this topic to fully understand the origin and role of parabens in the environment which will allow for a comprehensive understanding of the extent of environmental contamination and result in a representative assessment of the environmental risk that may pose.

Adsorption of a wide variety of antibiotics on graphene-based nanomaterials: A modelling study.

The knowledge on the sorption behaviour of antibiotics on nanomaterials is limited, especially regarding the reaction mechanism on the surface of carbon nanomaterials, which may determine both the adsorptive capacity and regeneration efficiency of graphene adsorbers. In this work, we used molecular modelling to generate the most comprehensive (to date) adsorption dataset for pristine and functionalised graphene interacting with 8 ß-lactams, 3 macrolide, 12 quinolone, 4 tetracycline, 15 sulphonamide, trimethoprim, 2 lincosamide, 2 phenicole and 4 nitroimidazole antibiotics, and their transformation products in water and n-octanol. Results show that various non-covalent interactions that operate simultaneously, including van der Waals dispersion forces, π-interactions, hydrophobic interaction and hydrogen bonding, facilitate adsorption. The molecular properties of antibiotics and graphene/graphene oxide, as well as the composition of the background solution regulate the magnitude of these interactions. Our findings demonstrate that the most efficient method for the removal of antibiotics from aquatic environments is the use of graphene at environmental pH. The subsequent regeneration of the sorbent is best achieved through washing with slightly basic (pH 8-10) non-polar solvents. The obtained theoretical insights expand and complement experimental observations and provide important information that can contribute to further exploration into the adsorbent properties of graphene-based materials, and towards the development of predictive adsorption models.

Plasma Membrane Calcium ATPase-Neuroplastin Complexes Are Selectively Stabilized in GM1-Containing Lipid Rafts.

The recent identification of plasma membrane (Ca2+)-ATPase (PMCA)-Neuroplastin (Np) complexes has renewed attention on cell regulation of cytosolic calcium extrusion, which is of particular relevance in neurons. Here, we tested the hypothesis that PMCA-Neuroplastin complexes exist in specific ganglioside-containing rafts, which could affect calcium homeostasis. We analyzed the abundance of all four PMCA paralogs (PMCA1-4) and Neuroplastin isoforms (Np65 and Np55) in lipid rafts and bulk membrane fractions from GM2/GD2 synthase-deficient mouse brains. In these fractions, we found altered distribution of Np65/Np55 and selected PMCA isoforms, namely PMCA1 and 2. Cell surface staining and confocal microscopy identified GM1 as the main complex ganglioside co-localizing with Neuroplastin in cultured hippocampal neurons. Furthermore, blocking GM1 with a specific antibody resulted in delayed calcium restoration of electrically evoked calcium transients in the soma of hippocampal neurons. The content and composition of all ganglioside species were unchanged in Neuroplastin-deficient mouse brains. Therefore, we conclude that altered composition or disorganization of ganglioside-containing rafts results in changed regulation of calcium signals in neurons. We propose that GM1 could be a key sphingolipid for ensuring proper location of the PMCA-Neuroplastin complexes into rafts in order to participate in the regulation of neuronal calcium homeostasis.

Salivary melatonin in oral squamous cell carcinoma patients.

Melatonin's role in circadian rhythm is well documented, as are its' anti-oxidant, oncostatic and anti-inflammatory properties. Poor sleep quality has been associated as a potential risk factor for several malignancies, including head and neck cancers. The purpose of this study is to determine salivary melatonin (MLT) levels in oral squamous cell carcinoma (OSCC) patients, compare the salivary MLT levels with those in healthy individuals and compare the salivary and serum levels in OSCC patients. Furthermore, the aim is to investigate the potential relationship between sleep quality and salivary MLT levels in OSCC patients. Unstimulated (UWS) and stimulated (SWS) whole saliva was sampled from patients with T1N0M0 and T2N0M0 OSCC (N = 34) and 33 sex and age matched healthy subjects. Serum samples were taken from 11 OSCC patients. Sleep quality was measured using Pittsburgh Sleep Quality Index (PSQI) questionnaire. Melatonin levels in UWS and SWS were significantly higher in the OSCC group. Sleep quality was significantly lower in patients with OSCC (P = 0.0001). ROC analysis was found to be significant (P < 0.001) in evaluating MLT concentration limit in diagnosing OSCC. The expected relationship between sleep quality and salivary MLT levels in OSCC patients was not observed. Our results suggest salivary MLT as a potential biomarker that might facilitate non-invasive detection of early stage OSCC.

UV filters as a driver of the antibiotic pollution in different water matrices.

Antibiotic pollution is frequently detected in fresh waters and wastewaters where they represent an environmental risk for the development of global antibiotic resistance. Due to their excessive use in personal care products, UV filters have also been found to be pseudo-persistent in the aquatic environment. In contrast to antibiotics, which can undergo photodegradation, UV filters are compounds designed to stably absorb UV radiation. This study explored the light based remediation of representative antibiotics from seven classes of antibiotics (fluoroquinolones, tetracyclines, penicillins, macrolide, glycolpeptide, sulphonamides and trimethoprim) in order to assess whether antibiotic pollution persists longer in the presence of organic UV filters. We show that the presence of UV filters either completely supresses or significantly alters the photodegradation of antibiotics in water. Advanced technologies in wastewater treatment, such as the use of UV C radiation, both effectively minimise the effect of UV filters and degrade most of the tested antibiotics proving to be effective management strategy. However, the half-life of erythromycin and amoxicillin, widely used antibiotics from macrolide- and penicillin-like classes, is extended in the presence of UV filters, even during UV C irradiation. Overall, the UV filters present within environmental mixtures are identified as important drivers of mixture toxicity, as they prolong antibiotic contamination of aquatic and engineered environments. The ramification of such finding is that inadequate consideration of UV filters may result in an imperfect prediction of the solar and UV light-based remediation of antibiotics, lead to improper classification of antibiotics persistence in the environment and cause non-optimal chemical fate and transport model performance. Use of the more benign compounds and assessment of the UV filters were identified as feasible management options in minimizing the influence of UV filters onto the remediation of antibiotics in aquatic environments.

Holo- and hemimetabolism of aquatic insects: Implications for a differential cross-ecosystem flux of metals.

Increased metal concentrations in aquatic habitats come as a result of both anthropogenic and natural sources. Emerging aquatic insects that play an indispensable role in these environments, transferring resources and energy to higher trophic levels in both aquatic and terrestrial habitats, may inadvertently also act as biovectors for metals and other contaminants. This study measured levels of 22 different metals detected in biofilm, aquatic and terrestrial life stages of Trichoptera and Odonata, as well as riparian spiders, to examine the uptake and transfer from freshwater to terrestrial ecosystems. We show that emerging insects transfer metals from aquatic to terrestrial ecosystems, however with large losses observed on the boundary of these two environments. Significantly lower concentrations of most metals in adult insects were observed in both hemimetabolous (Odonata) and holometabolous insect orders (Trichoptera). In holometabolous Trichoptera, however, this difference was greater between aquatic life stages (larvae to pupae) compared to that between pupae and adults. Trophic transfer may have also played a role in decreasing metal concentrations, as metal concentrations generally adhered to the following pattern: biofilm > aquatic insects > terrestrial invertebrates. Exceptions to this observation were detected with a handful of essential (Cu, Zn, Se) and non-essential metals (Cd, Ag), which measured higher concentrations in adult aquatic insects compared to their larval counterparts, as well as in aquatic and terrestrial predators compared to their prey. Overall, all metals were found to be bioavailable and biotransferred from contaminated waters to terrestrial invertebrates to some degree, suggesting that risks associated with metal-contaminated freshwaters could extend to terrestrial systems through the emergence of these potential invertebrate biovectors.

Aquatic Insects Transfer Pharmaceuticals and Endocrine Disruptors from Aquatic to Terrestrial Ecosystems.

A wide range of pharmaceuticals and endocrine disrupting compounds enter freshwaters globally. As these contaminants are transported through aquatic food webs, understanding their impacts on both aquatic and terrestrial ecosystems remains a major challenge. Here, we provide the first direct evidence of the transfer of pharmaceuticals and endocrine disruptors through the aquatic-terrestrial habitat linkage by emerging aquatic insects. We also show that the type of insect metamorphosis and feeding behavior determine the bioaccumulation patterns of these contaminants. Adult Trichoptera, an important food source for riparian predators, showed an increased body burden of pharmaceuticals and endocrine disruptors. This implies that terrestrial predators, such as spiders, birds, and bats, are exposed to mixtures of pharmaceuticals and endocrine disruptors of aquatic origin, which may impact their physiology and population dynamics. Overall, our study provides valuable insights into the bioaccumulation patterns and trophic cross-ecosystem transfer of these contaminants, from aquatic primary producers to terrestrial predators.

Modelling of the adsorption of pharmaceutically active compounds on carbon-based nanomaterials.

Understanding and acquiring knowledge about the adsorption of pharmaceuticals on carbon-based nanomaterials (CNMs) is imperative to the chemical engineering applications of CNMs, as well as to risk assessment and pollution control of both CNMs and pharmaceuticals. A computational assessment of the mechanism and thermodynamics of the adsorption of 18 most common pharmaceuticals (acetaminophen, acetylsalicylic acid, atenolol, caffeine, carbamazepine, clofibric acid, diclofenac, fenofibric acid, fluoxetine, gemfibrozil, ibuprofen, ketoprofen, naproxen, phenazone, primidone, propranolol, salicylic acid, tramadol) on four different CNMs (pristine/functionalised graphene and carbon nanotube) in two different solvents (water and n-octanol) was provided. We show that the adsorption of pharmaceuticals on pristine CNMs is controlled by dispersion forces, π-interactions and hydrophobic interaction. On the other hand, adsorption on functionalised CNMs is controlled by hydrogen bonding and Coulombic interactions. Furthermore, we demonstrate how functionalization of CNM, CNM curvature and background solution properties modulate the intensity of non-covalent interactions and their contribution towards adsorption free energy. With this knowledge, we pinpoint functionalised graphene at environmental pH as the most effective setting for the removal of a given set of pharmaceuticals from water and wastewater. Finally, we show that CNMs may transport pharmaceuticals into living organisms and release them in nonpolar mediums such as cellular membranes and fat cells.

Aquatic macroinvertebrates under stress: Bioaccumulation of emerging contaminants and metabolomics implications.

The current knowledge on bioaccumulation of emerging contaminants (ECs) in aquatic invertebrates exposed to the realistic environmental concentrations is limited. Even less is known about the effects of chemical pollution exposure on the metabolome of aquatic invertebrates. We conducted an in situ translocation experiment with passive filter-feeding caddisfly larvae (Hydropsyche sp.) in an effluent-influenced river in order to i) unravel the bioaccumulation (and recovery) dynamics of ECs in aquatic invertebrates, and ii) test whether exposure to environmentally realistic concentrations of ECs will translate into metabolic profile changes in the insects. The experiment was carried out at two sites, upstream and downstream of the discharge of an urban wastewater treatment plant effluent. The translocated animals were collected at 2-week intervals for 46 days. Both pharmaceuticals and endocrine disrupting compounds (EDCs) were detected in water (62 and 7 compounds, respectively), whereas in Hydropsyche tissues 5 EDCs accumulated. Overall, specimens from the upstream site translocated to the impacted site reached higher ECs concentrations in their tissues, as a reflection of the contaminants' water concentrations. However, bioaccumulation was a temporary process susceptible to change under lower contaminant concentrations. Non-targeted metabolite profiling detected fine metabolic changes in translocated Hydropsyche larvae. Both translocations equally induced stress, but it was higher in animals translocated to the impacted site.

Photocatalytic Degradation of Azithromycin by Nanostructured TiO2 Film: Kinetics, Degradation Products, and Toxicity.

In this paper, nanostructured TiO2 film was prepared by the by sol-gel process and dip-coating technique with titanium tetraisopropoxide as a precursor. After heat treatment at 550 °C, the deposited film was characterized by means of micro-Raman spectroscopy and atomic force microscopy (AFM). It was found that the TiO2 film consisted of only the TiO2 anatase phase and showed a granular microstructure. Photocatalytic degradation of azithromycin by using sol-gel nanostructured TiO2 film was studied to define the most effective degradation process for potential use in wastewater treatment. Different factors were evaluated during photocatalysis, such as pH (3, 7, and 10), water matrix (ultrapure water and synthetic municipal waste water effluent), influence of another pharmaceutically active compound (sulfamethoxazole, one of the most often detected pharmaceutic compounds in waste waters), and radiation sources (low pressure ultraviolet (UV) mercury lamps with a UV-A and UV-C range; a light-emitting diode (LED) lamp with a radiation peak at 365 nm). The most effective degradation process was achieved with the UV-C irradiation source in matrices at pH 10. The water matrix had little effect on the photocatalytic degradation rates of azithromycin. The presence of sulfamethoxazole in the water matrix decreased the degradation rate of azithromycin, however, only in matrices with a pH level adjusted to 10. During the experiments, five azithromycin degradation products were identified and none of them showed toxic properties, suggesting effective removal of azithromycin. LED 365 nm as the irradiation source was not as effective as the UV-C lamp. Nevertheless, considering the cost, energy efficiency, and environmental aspects of the irradiation source, the LED lamp could be a "real-life" alternative.

Extraction and cleansing of data for a non-targeted analysis of high-resolution mass spectrometry data of wastewater.

We provide a workflow to extract unidentified signals from chromatography-high resolution mass spectrometry (LC-HRMS) data of wastewater samples as a pre-step of a non-targeted analysis of dissolved organic matter (DOM). We provide detailed methodology on data processing and cleanup using MS processing software MZmine 2 and an own set of functions in R developed for wastewater analysis. The processing involves signal extraction, linear mass correction, reduction of noise, grouping of isotopologues, molecular formula assignment and merging of replicates. The article contains software settings and reasoning behind the choice of data extraction options. The supplementary information contains a script for the correction of signal masses using internal standards and templates of internal standard lists. We included a reproducible example as an R notebook with data cleansing workflow and data exported from MZmine. The data were used according to the described methodology in the article "A non-targeted high-resolution mass spectrometry data analysis of dissolved organic matter in wastewater treatment" by Verkh et al., 2018. •Includes a linear mass correction algorithm for LC-HRMS signals.•Describes a pipeline of non-targeted processing of LC-HRMS data of wastewater using free software.•Provides tests and reasons for parameter choice in non-targeted LC-HRMS wastewater data extraction.

A non-targeted high-resolution mass spectrometry data analysis of dissolved organic matter in wastewater treatment.

The dissolved organic matter (DOM) in wastewater is typically described by a limited number of concentration measurements of select DOM fractions or micro-contaminants, which determine the removal efficiency in a wastewater treatment. Current methods do not necessarily reflect the true performance of the treatment with regard to environmental and public health risk. Herein we describe the development and application of a non-targeted liquid chromatography-high resolution mass spectrometry (LC-HRMS) data analysis for the evaluation of wastewater treatment processes. Our data analysis approach was applied to a real wastewater system with secondary biological treatment and tertiary treatment consisting of sand filtration, UV-treatment, and chlorination. We identified significant changes in DOM during wastewater treatment. The secondary treatment removed 1617 of 2409 (67%) detected molecular features (grouped isotopologues belonging to the same molecule) from the influent while 255 of 1047 (24%) new molecular features appeared in the secondary effluent. A reduction in the number of large molecules (>450 Da) and an increase in unsaturated molecular features of the effluent organic matter was observed. Van Krevelen plots revealed the distribution of unsaturation and heteroatoms and Kendrick mass defect plots uncovered CH2 homologous series implying a removal of heavy constituents in that fraction. The demonstrated approach is a step towards a more comprehensive monitoring of DOM in wastewater and contributes to the understanding of current treatment technologies.

Effects of chronic pollution and water flow intermittency on stream biofilms biodegradation capacity.

A mesocosm case study was conducted to gain understanding and practical knowledge on biofilm emerging contaminants biodegradation capacity under stressor and multiple stressor conditions. Two real life scenarios: I) biodegradation in a pristine intermittent stream experiencing acute pollution and II) biodegradation in a chronically polluted intermittent stream, were examined via a multifactorial experiment using an artificial stream facility. Stream biofilms were exposed to different water flow conditions i.e. permanent and intermittent water flow. Venlafaxine, a readily biodegradable pharmaceutical was used as a measure of biodegradation capacity while pollution was simulated by a mixture of four emerging contaminants (erythromycin, sulfisoxazole, diclofenac and imidacloprid in addition to venlafaxine) in environmentally relevant concentrations. Biodegradation kinetics monitored via LC-MS/MS was established, statistically evaluated, and used to link biodegradation with stress events. The results suggest that the effects of intermittent flow do not hinder and may even stimulate pristine biofilm biodegradation capacity. Chronic pollution completely reduced biodegradation in permanent water flow experimental treatments while no change in intermittent streams was observed. A combined effect of water flow conditions and emerging contaminants exposure on biodegradation was found. The decrease in biodegradation due to exposure to emerging contaminants is significantly greater in streams with permanent water flow suggesting that the short and medium term biodegradation capacity in intermittent systems may be preserved or even greater than in perennial streams.

Aberrant ganglioside composition in glioblastoma multiforme and peritumoral tissue: A mass spectrometry characterization.

Tumor cells are characterized by aberrant glycosylation of the cell surface glycoconjugates. Gangliosides are sialylated glycosphingolipids highly abundant in neural tissue and considered as tumor markers and therapeutic targets. In this study, a detailed characterization of native ganglioside mixtures from glioblastoma multiforme, corresponding peritumoral tissue and healthy human brain was performed using mass spectrometry and high performance thin layer chromatography in order to elucidate their roles as tumor-associated antigens. Distinctive changes in ganglioside expression were determined in glioblastoma compared to healthy brain tissue showing 5 times lower total ganglioside content and higher abundance of simple gangliosides. Glioblastoma gangliosides were characterized by highly diverse ceramide composition with fatty acyl chains varying from 16 to 24 carbon atoms, while in normal and peritumoral tissue mostly C18 chains were found. The most abundant ganglioside in glioblastoma was GD3 (d18:1/18:0), followed by GD3 (d18:1/24:0) that was exclusively detected in glioblastoma tissue. Peritumoral tissue expressed higher abundance of GD3- and nLM1/GM1-species while lower GT1-species vs. normal brain. O-Ac-GD1, known as neurostatin, was detected in normal and peritumoral tissue, but not in glioblastoma. O-Ac-GD3 species were found exclusively in glioblastoma; MS structural characterization of the isomeric form possessing the O-acetylation at the inner sialic acid residue confirmed our previous finding that this isomer is glioma-associated. This, to our knowledge, the most detailed characterization of ganglioside composition in glioblastoma and peritumoral tissue, especially addressing the ceramide variability and O-acetylation of tumor-associated gangliosides, could contribute to recognition of new molecular targets for glioblastoma treatment and sub-classification.