Post-treatment of ozonated wastewater with activated carbon and biofiltration compared to membrane bioreactors: Toxicity removal in vitro and in Potamopyrgus antipodarum.

Wastewater treatment plants are major point sources of (micro)pollutant emissions and advanced wastewater treatment technologies can improve their removal capacity. While abundant data on individual advanced treatment technologies is available, there is limited knowledge regarding the removal performance of ozonation combined with multiple post-treatments and stand-alone membrane bioreactors. This is especially true for the removal of in vitro and in vivo toxicity. Therefore, we investigated the removal of 40 micropollutants and toxicity by a pilot-scale ozonation with four post-treatments: non-aerated and aerated granular activated carbon and biological filtration. In addition, two stand-alone membrane bioreactors fed with untreated wastewater and one MBR operating with ozonated partial flow recirculation were analysed. Aqueous and extracted samples were analysed in vitro for (anti)estrogenic, (anti)androgenic and mutagenic effects. To assess in vivo effects, the mudsnail Potamopyrgus antipodarum was exposed in an on-site flow-through system. Multiple in vitro effects were detected in conventionally treated wastewater including estrogenic and anti-androgenic activity. Ozonation largely removed these effects, while anti-estrogenic and mutagenic effects increased suggesting the formation of toxic transformation products. These effects were significantly reduced by granular activated carbon being more effective than biological filtration. The membrane bioreactor performed similarly to the conventional treatment while the membrane bioreactor with ozonation had a comparable removal performance like ozonation. Conventionally treated wastewater increased the growth of P. antipodarum. Ozonation reduced the reproduction indicating a potential formation of toxic transformation products. In the post-treatments, these effects were compensated or remained unaffected. The effluents of the membrane bioreactors induced reproductive toxicity. Our results show that ozonation is effective in further reducing toxicity and micropollutant concentrations. However, the formation of toxicity requires a post-treatment. Here, ozonation coupled to granular activated carbon filtration seemed the most promising treatment process.

The role of BDNF methylation and Val66 Met in amygdala reactivity during emotion processing.

Epigenetic alterations of the brain-derived neurotrophic factor (BDNF) gene have been associated with psychiatric disorders in humans and with differences in amygdala BDNF mRNA levels in rodents. This human study aimed to investigate the relationship between the functional BDNF-Val66 Met polymorphism, its surrounding DNA methylation in BDNF exon IX, amygdala reactivity to emotional faces, and personality traits. Healthy controls (HC, n = 189) underwent functional MRI during an emotional face-matching task. Harm avoidance, novelty seeking and reward dependence were measured using the Tridimensional Personality Questionnaire (TPQ). Individual BDNF methylation profiles were ascertained and associated with several BDNF single nucleotide polymorphisms surrounding the BDNF-Val66 Met, amygdala reactivity, novelty seeking and harm avoidance. Higher BDNF methylation was associated with higher amygdala reactivity (x = 34, y = 0, z = -26, t(166) = 3.00, TFCE = 42.39, p(FWE) = .045), whereby the BDNF-Val66 Met genotype per se did not show any significant association with brain function. Furthermore, novelty seeking was negatively associated with BDNF methylation (r = -.19, p = .015) and amygdala reactivity (r = -.17, p = .028), while harm avoidance showed a trend for a positive association with BDNF methylation (r = .14, p = .066). The study provides first insights into the relationship among BDNF methylation, BDNF genotype, amygdala reactivity and personality traits in humans, highlighting the multidimensional relations among genetics, epigenetics, and neuronal functions. The present study suggests a possible involvement of epigenetic BDNF modifications in psychiatric disorders and related brain functions, whereby high BDNF methylation might reduce BDNF mRNA expression and upregulate amygdala reactivity.

Deficiency of the palmitoyl acyltransferase ZDHHC7 impacts brain and behavior of mice in a sex-specific manner.

The palmitoyl acyltransferase ZDHHC7 belongs to the DHHC family responsible for the covalent attachment of palmitic acid (palmitoylation) to target proteins. Among synaptic proteins, its main targets are sex steroid receptors such as the estrogen receptors. When palmitoylated, these couple to membrane microdomains and elicit non-genomic rapid responses. Such coupling is found particularly in cortico-limbic brain areas which impact structure, function, and behavioral outcomes. Thus far, the functional role of ZDHHC7 has not been investigated in this context. To directly analyze an impact of ZDHHC7 on brain anatomy, microstructure, connectivity, function, and behavior, we generated a mutant mouse in which the Zdhhc7 gene is constitutively inactivated. Male and female Zdhhc7-/- mice were phenotypically compared with wild-type mice using behavioral tests, electrophysiology, protein analyses, and neuroimaging with diffusion tensor-based fiber tractography. Zdhhc7-deficiency impaired excitatory transmission, synaptic plasticity at hippocampal Schaffer collateral CA1 synapses, and hippocampal structural connectivity in both sexes in similar manners. Effects on both sexes but in different manners appeared in medial prefrontal cortical synaptic transmission and in hippocampal microstructures. Finally, Zdhhc7-deficiency affected anxiety-related behaviors exclusively in females. Our data demonstrated the importance of Zdhhc7 for assembling proper brain structure, function, and behavior on a system level in mice in a sex-related manner. Given the prominent role of sex-specificity also in humans and associated mental disorders, Zdhhc7-/- mice might provide a promising model for in-depth investigation of potentially underlying sex-specifically altered mechanisms.

What you extract is what you see: Optimising the preparation of water and wastewater samples for in vitro bioassays.

The assessment of water quality is crucial for safeguarding drinking water resources and ecosystem integrity. To this end, sample preparation and extraction is critically important, especially when investigating emerging contaminants and the toxicity of water samples. As extraction methods are rarely optimised for bioassays but rather adopted from chemical analysis, this may result in a misrepresentation of the actual toxicity. In this study, surface water, groundwater, hospital and municipal wastewater were used to characterise the impacts of common sample preparation techniques (acidification, filtration and solid phase extraction (SPE)) on the outcomes of eleven in vitro bioassays. The latter covered endocrine activity (reporter gene assays for estrogen, androgen, aryl-hydrocarbon, retinoic acid, retinoid X, vitamin D, thyroid receptor), mutagenicity (Ames fluctuation test), genotoxicity (umu test) and cytotoxicity. Water samples extracted using different SPE sorbents (Oasis HLB, Supelco ENVI-Carb+, Telos C18/ENV) at acidic and neutral pH were compared for their performance in recovering biological effects. Acidification, commonly used for stabilisation, significantly altered the endocrine activity and toxicity of most (waste)water samples. Sample filtration did not affect the majority of endpoints but in certain cases affected the (anti-)estrogenic and dioxin-like activities. SPE extracts (10.4 × final concentration), including WWTP effluents, induced significant endocrine effects that were not detected in aqueous samples (0.63 × final concentration), such as estrogenic, (anti-)androgenic and dioxin-like activities. When ranking the SPE methods using multivariate Pareto optimisation an extraction with Telos C18/ENV at pH 7 was most effective in recovering toxicity. At the same time, these extracts were highly cytotoxic masking the endpoint under investigation. Compared to that, extraction at pH 2.5 enriched less cytotoxicity. In summary, our study demonstrates that sample preparation and extraction critically affect the outcome of bioassays when assessing the toxicity of water samples. Depending on the water matrix and the bioassay, these methods need to be optimised to accurately assess water quality.

Ecotoxicological impacts of surface water and wastewater from conventional and advanced treatment technologies on brood size, larval length, and cytochrome P450 (35A3) expression in Caenorhabditis elegans.

Anthropogenic micropollutants and transformation products (TPs) negatively affect aquatic ecosystems and water resources. Wastewater treatment plants (WWTP) represent major point sources for (micro)pollutants and TPs in urban water cycles. The aim of the current study was to assess the removal of micropollutants and toxicity during conventional and advanced wastewater treatment. Using wild-type and transgenic Caenorhabditis elegans, the endpoint reproduction, growth, and cytochrome P450 (CYP) 35A3 induction (via cyp-35A3::GFP) were assessed. Samples were collected at four WWTPs and a receiving surface water. One WWTP included the advanced treatments: ozonation followed by granular activated carbon (GAC) or biological filtration (BF), respectively. Relevant micropollutants and WWTP parameters (n = 111) were included. Significant reproductive toxicity was detected for one WWTP effluent (31-83% reduced brood size). Three of four effluents significantly promoted the growth of C. elegans larvae (49-55% increased lengths). This effect was also observed for the GAC (34-41%) and BF (30%) post-treatments. Markedly, significant cyp-35A3::GFP induction was detected for one effluent before and after ozonation, being more pronounced for the ozonated samples (5- and 7.4-fold above controls). While the advanced treatments decreased the concentrations of most micropollutants, the observed effects may be attributed to effects of residual target compounds and/or compounds not included in the target chemical analysis. This highlights the need for an integrated assessment of (advanced) wastewater treatment covering both biological and chemical parameters.

Association of Serotonin Transporter Gene AluJb Methylation with Major Depression, Amygdala Responsiveness, 5-HTTLPR/rs25531 Polymorphism, and Stress.

DNA methylation profiles of the serotonin transporter gene (SLC6A4) have been shown to alter SLC6A4 expression, drive antidepressant treatment response and modify brain functions. This study investigated whether methylation of an AluJb element in the SLC6A4 promotor was associated with major depressive disorder (MDD), amygdala reactivity to emotional faces, 5-HTTLPR/rs25531 polymorphism, and recent stress. MDD patients (n=122) and healthy controls (HC, n=176) underwent fMRI during an emotional face-matching task. Individual SLC6A4 AluJb methylation profiles were ascertained and associated with MDD, amygdala reactivity, 5-HTTLPR/rs25531, and stress. SLC6A4 AluJb methylation was significantly lower in MDD compared to HC and in stressed compared to less stressed participants. Lower AluJb methylation was particularly found in 5-HTTLPR/rs25531 risk allele carriers under stress and correlated with less depressive episodes. fMRI analysis revealed a significant interaction of AluJb methylation and diagnosis in the amygdala, with MDD patients showing lower AluJb methylation associated with decreased amygdala reactivity. While no joint effect of AluJb methylation and 5-HTTLPR/rs25531 existed, risk allele carriers showed significantly increased bilateral amygdala activation. These findings suggest a role of SLC6A4 AluJb methylation in MDD, amygdala reactivity, and stress reaction, partly interwoven with 5-HTTLPR/rs25531 effects. Patients with low methylation in conjunction with a shorter MDD history and decreased amygdala reactivity might feature a more stress-adaptive epigenetic process, maybe via theoretically possible endogenous antidepressant-like effects. In contrast, patients with higher methylation might possibly suffer from impaired epigenetic adaption to chronic stress. Further, the 5-HTTLPR/rs25531 association with amygdala activation was confirmed in our large sample.

Differential Abnormal Pattern of Anterior Cingulate Gyrus Activation in Unipolar and Bipolar Depression: an fMRI and Pattern Classification Approach.

Distinguishing bipolar disorder from major depressive disorder is a major challenge in psychiatric treatment. Consequently, there has been growing interest in identifying neuronal biomarkers of disorder-specific pathophysiological processes to differentiate affective disorders. Thirty-six depressed bipolar patients, 36 depressed unipolar patients, and 36 matched healthy controls (HCs) participated in an fMRI experiment. Emotional faces served as stimuli in a matching task. We investigated neural activation towards angry, fearful, and happy faces focusing on prototypical regions related to emotion processing, ie, the amygdala and the anterior cingulate gyrus (ACG). Furthermore, we employed a whole-brain and a multivariate pattern classification analysis. Unipolar patients showed abnormally reduced ACG activation toward happy and fearful faces compared with bipolar patients and HCs respectively. Furthermore, the whole-brain analysis revealed significantly increased activation in bipolar patients compared with unipolar patients in the fearful condition in the right frontal and parietal cortex. Moreover, the multivariate pattern classification analysis yielded significant classification rates of up to 72% based on ACG activation elicited by fearful faces. Our results question the rather 'amygdalocentric' neurobiological models of mood disorders. We observed patterns of abnormally reduced ventral and supragenual ACG activation, potentially indicating impaired bottom-up emotion processing and automatic emotion regulation specifically in unipolar but not in bipolar individuals.

Impact of an estrogenic sewage treatment plant effluent on life-history traits of the freshwater amphipod Gammarus pulex.

Despite efforts to upgrade sewage treatment plants (STPs) in the last decades, STPs are still a major source for the contamination of surface waters, including emerging pollutants such as pesticides, pharmaceuticals, personal care products and endocrine disrupting chemicals (EDCs). Because many of these substances are not completely removed in conventional STPs they are regularly detected in surface waters where they have the potential to affect local macroinvertebrate communities. The objective of the current work was to investigate the impact of an estrogenic wastewater effluent on the key life-history traits of the freshwater amphipod Gammarus pulex. G. pulex was exposed in artificial indoor flow-channels under constant conditions to different wastewater concentrations (0%, 33%, 66%, 100%). In parallel the estrogenic activity of wastewater samples was determined using the yeast estrogen screen (YES). Estrogenic activities in the STP effluent were up to 38.6 ng/L estradiol equivalents (EEQ). Amphipods exhibited an increasing body length with increasing wastewater concentrations. Furthermore, we observed a shift of the sex ratio in favour of females, a significantly increased fraction of brooding females and increased fecundity indices with increasing wastewater concentrations. The increased body length is likely to be attributed to the additional nutrient supply while the occurrence of EDCs in the wastewater is the probable cause for the altered sex ratio and fecundity in exposed Gammarus cohorts.

Combined effects of silver nanoparticles and 17α-ethinylestradiol on the freshwater mudsnail Potamopyrgus antipodarum.

Ecotoxicological studies have shown that nanosilver is among the most toxic nanomaterials to aquatic organisms. However, research has so far focused on the determination of acute effects. Combined effects of nanosilver with other substances have not yet been studied in aquatic organisms. The present study aimed to investigate the chronic toxicity of nanosilver as well as the potential of nanosilver to influence the effects of co-occurring substances on the freshwater mudsnail Potamopyrgus antipodarum. In 28-day chronic toxicity experiments, the effects of nanosilver on the reproduction of P. antipodarum were assessed. In order to evaluate the influence of nanosilver on other substances, 17α-ethinylestradiol (EE2) was chosen as model compound due to the well-characterized effects on P. antipodarum. In addition to effects on reproduction, exposure to nanosilver and EE2 was monitored by determining the expression of estrogen-responsive transcripts (estrogen receptor and vitellogenin encoding genes). Exposure to nanosilver decreased the reproduction of P. antipodarum (EC10: 5.57 µg l(-1); EC50: 15.0 µg l(-1)). Exposure to EE2 significantly stimulated the embryo production at 25 ng l(-1). The presence of nanosilver led to increased EE2 effects at EE2 concentrations that had no influence on reproduction when applied in absence of nanosilver. In contrast, combined exposure to nanosilver decreased EE2 effects at concentrations that stimulated reproduction and the expression of estrogen responsive genes when applied in the absence of nanosilver. This is the first study demonstrating an influence of nanosilver on the effects of co-contaminants on aquatic organisms. The study further highlights the need for chronic experiments to properly assess environmental risks of nanosilver and their effects on co-occurring contaminants.

Serotonin transporter gene methylation is associated with hippocampal gray matter volume.

BACKGROUND: The serotonin transporter (5-HTT) and the 5-HTTLPR/rs25531 polymorphisms in its gene (SLC6A4) have been associated with depression, increased stress-response, and brain structural alterations such as reduced hippocampal volumes. Recently, epigenetic processes including SLC6A4 promoter methylation were shown to be affected by stress, trauma, or maltreatment and are regarded to be involved in the etiology of affective disorders. However, neurobiological correlates of SLC6A4 promoter methylation have never been studied or compared to genotype effects by means of human neuroimaging hitherto METHODS: Healthy subjects were recruited in two independent samples (N = 94, N = 95) to obtain structural gray matter images processed by voxel-based morphometry (VBM8), focusing on hippocampal, amygdala, and anterior cingulate gyrus gray matter structure. SLC6A4 promoter methylation within an AluJb element and 5-HTTLPR/rs25531 genotypes were analyzed in view of a possible impact on local gray matter volume RESULTS: Strong associations of AluJb methylation and hippocampal gray matter volumes emerged within each sample separately, which in the combined sample withstood most conservative alpha-corrections for the entire brain. The amygdala, insula, and caudate nucleus showed similar associations. The 5-HTTLPR/rs25531 showed no main effect on gray matter, and the effect of methylation rates on hippocampal structure was comparable among the genotype groups CONCLUSIONS: Methylation within the AluJb appears to have strong effects on hippocampal gray matter volumes, indicating that epigenetic processes can alter brain structures crucially involved in stress-related disorders. Different ways of regulating SLC6A4 expression might involve exonization or transcription factor binding as potentially underlying mechanisms, which, however, is speculative and warrants further investigation.