85 research outputs found
Do contaminants originating from state-of-the-art treated wastewater impact the ecological quality of surface waters?
Since the 1980s, advances in wastewater treatment technology have led to considerably improved surface water quality in the urban areas of many high income countries. However, trace concentrations of organic wastewater-associated contaminants may still pose a key environmental hazard impairing the ecological quality of surface waters. To identify key impact factors, we analyzed the effects of a wide range of anthropogenic and environmental variables on the aquatic macroinvertebrate community. We assessed ecological water quality at 26 sampling sites in four urban German lowland river systems with a 0–100% load of state-of-the-art biological activated sludge treated wastewater. The chemical analysis suite comprised 12 organic contaminants (five phosphor organic flame retardants, two musk fragrances, bisphenol A, nonylphenol, octylphenol, diethyltoluamide, terbutryn), 16 polycyclic aromatic hydrocarbons, and 12 heavy metals. Non-metric multidimensional scaling identified organic contaminants that are mainly wastewater-associated (i.e., phosphor organic flame retardants, musk fragrances, and diethyltoluamide) as a major impact variable on macroinvertebrate species composition. The structural degradation of streams was also identified as a significant factor. Multiple linear regression models revealed a significant impact of organic contaminants on invertebrate populations, in particular on Ephemeroptera, Plecoptera, and Trichoptera species. Spearman rank correlation analyses confirmed wastewater-associated organic contaminants as the most significant variable negatively impacting the biodiversity of sensitive macroinvertebrate species. In addition to increased aquatic pollution with organic contaminants, a greater wastewater fraction was accompanied by a slight decrease in oxygen concentration and an increase in salinity. This study highlights the importance of reducing the wastewater-associated impact on surface waters. For aquatic ecosystems in urban areas this would lead to: (i) improvement of the ecological integrity, (ii) reduction of biodiversity loss, and (iii) faster achievement of objectives of legislative requirements, e.g., the European Water Framework Directive
Urinary concentrations of GHB and its novel amino acid and carnitine conjugates following controlled GHB administration to humans
Gamma-hydroxybutyrate (GHB) remains a challenging clinical/forensic toxicology drug. Its rapid elimination to endogenous levels mainly causes this. Especially in drug-facilitated sexual assaults, sample collection often occurs later than the detection window for GHB. We aimed to investigate new GHB conjugates with amino acids (AA), fatty acids, and its organic acid metabolites for their suitability as ingestion/application markers in urine following controlled GHB administration to humans. We used LC–MS/MS for validated quantification of human urine samples collected within two randomized, double-blinded, placebo-controlled crossover studies (GHB 50 mg/kg, 79 participants) at approximately 4.5, 8, 11, and 28 h after intake. We found significant differences (placebo vs. GHB) for all but two analytes at 4.5 h. Eleven hours post GHB administration, GHB, GHB-AAs, 3,4-dihydroxybutyric acid, and glycolic acid still showed significantly higher concentrations; at 28 h only GHB-glycine. Three different discrimination strategies were evaluated: (a) GHB-glycine cut-off concentration (1 µg/mL), (b) metabolite ratios of GHB-glycine/GHB (2.5), and (c) elevation threshold between two urine samples (> 5). Sensitivities were 0.1, 0.3, or 0.5, respectively. Only GHB-glycine showed prolonged detection over GHB, mainly when compared to a second time- and subject-matched urine sample (strategy c)
Interactive effects of mGlu5 and 5-HT2A receptors on locomotor activity in mice
RationaleMetabotropic glutamate (mGlu) receptors have been suggested to play a role in neuropsychiatric disorders including schizophrenia, drug abuse, and depression. Because serotonergic hallucinogens increase glutamate release and mGlu receptors modulate the response to serotonin (5-HT)(2A) activation, the interactions between serotonin 5-HT(2A) receptors and mGlu receptors may prove to be important for our understanding of these diseases.ObjectiveWe tested the effects of the serotonergic hallucinogen and 5-HT(2A) agonist, 2,5-dimethoxy-4-methylamphetamine (DOM), and the selective 5-HT(2A) antagonist, M100907, on locomotor activity in the mouse behavioral pattern monitor (BPM) in mGlu5 wild-type (WT) and knockout (KO) mice on a C57 background.ResultsBoth male and female mGlu5 KO mice showed locomotor hyperactivity and diminished locomotor habituation compared with their WT counterparts. Similarly, the mGlu5-negative allosteric modulator 2-methyl-6-(phenylethynyl)pyridine (MPEP) also increased locomotor hyperactivity, which was absent in mGlu5 KO mice. The locomotor hyperactivity in mGlu5 receptor KO mice was potentiated by DOM (0.5 mg/kg, subcutaneously (SC)) and attenuated by M100907 (1.0 mg/kg, SC). M100907 (0.1 mg/kg, SC) also blocked the hyperactivity induced by MPEP.ConclusionsThese studies demonstrated that loss of mGlu5 receptor activity either pharmacologically or through gene deletion leads to locomotor hyperactivity in mice. Additionally, the gene deletion of mGlu5 receptors increased the behavioral response to the 5-HT(2A) agonist DOM, suggesting that mGlu5 receptors either mitigate the behavioral effects of 5-HT(2A) hallucinogens or that mGlu5 KO mice show an increased sensitivity to 5-HT(2A) agonists. Taken together, these studies indicate a functional interaction between mGlu5 and 5-HT(2A) receptors
Association between age of cannabis initiation and gray matter covariance networks in recent onset psychosis
Cannabis use during adolescence is associated with an increased risk of developing psychosis. According to a current hypothesis, this results from detrimental effects of early cannabis use on brain maturation during this vulnerable period. However, studies investigating the interaction between early cannabis use and brain structural alterations hitherto reported inconclusive findings. We investigated effects of age of cannabis initiation on psychosis using data from the multicentric Personalized Prognostic Tools for Early Psychosis Management (PRONIA) and the Cannabis Induced Psychosis (CIP) studies, yielding a total sample of 102 clinically-relevant cannabis users with recent onset psychosis. GM covariance underlies shared maturational processes. Therefore, we performed source-based morphometry analysis with spatial constraints on structural brain networks showing significant alterations in schizophrenia in a previous multisite study, thus testing associations of these networks with the age of cannabis initiation and with confounding factors. Earlier cannabis initiation was associated with more severe positive symptoms in our cohort. Greater gray matter volume (GMV) in the previously identified cerebellar schizophrenia-related network had a significant association with early cannabis use, independent of several possibly confounding factors. Moreover, GMV in the cerebellar network was associated with lower volume in another network previously associated with schizophrenia, comprising the insula, superior temporal, and inferior frontal gyrus. These findings are in line with previous investigations in healthy cannabis users, and suggest that early initiation of cannabis perturbs the developmental trajectory of certain structural brain networks in a manner imparting risk for psychosis later in life
αCaMKII controls the establishment of cocaine's reinforcing effects in mice and humans
Although addiction develops in a considerable number of regular cocaine users, molecular risk factors for cocaine dependence are still unknown. It was proposed that establishing drug use and memory formation might share molecular and anatomical pathways. Alpha-Ca(2+)/calmodulin-dependent protein kinase-II (αCaMKII) is a key mediator of learning and memory also involved in drug-related plasticity. The autophosphorylation of αCaMKII was shown to accelerate learning. Thus, we investigated the role of αCaMKII autophosphorylation in the time course of establishing cocaine use-related behavior in mice. We found that αCaMKII autophosphorylation-deficient αCaMKII(T286A) mice show delayed establishment of conditioned place preference, but no changes in acute behavioral activation, sensitization or conditioned hyperlocomotion to cocaine (20 mg kg(-1), intraperitoneal). In vivo microdialysis revealed that αCaMKII(T286A) mice have blunted dopamine (DA) and blocked serotonin (5-HT) responses in the nucleus accumbens (NAcc) and prefrontal cortex after acute cocaine administration (20 mg kg(-1), intraperitoneal), whereas noradrenaline responses were preserved. Under cocaine, the attenuated DA and 5-HT activation in αCaMKII(T286A) mice was followed by impaired c-Fos activation in the NAcc. To translate the rodent findings to human conditions, several CAMK2A gene polymorphisms were tested regarding their risk for a fast establishment of cocaine dependence in two independent samples of regular cocaine users from Brazil (n=688) and Switzerland (n=141). A meta-analysis across both samples confirmed that CAMK2A rs3776823 TT-allele carriers display a faster transition to severe cocaine use than C-allele carriers. Together, these data suggest that αCaMKII controls the speed for the establishment of cocaine's reinforcing effects
Sensorimotor gating of schizophrenia patients is influenced by 5-HT2A receptor polymorphisms
Background: Schizophrenia patients exhibit impairment in prepulse inhibition (PPI) of the acoustic startle response (ASR) suggesting a sensorimotor gating deficit. The serotonin-2A receptor (5-HT2AR) has been implicated in both the pathogenesis of schizophrenia and the PPI deficits of schizophrenia patients. Moreover, both schizophrenia and PPI are thought to be inheritable. Thus, we investigated the impact of three 5-HT2AR polymorphisms (A-1438G, T102C, H452Y) on PPI in schizophrenia patients.
Methods: We analyzed the 5-HT2AR A-1438G, T102C, and H452Y polymorphisms and assessed startle reactivity, habituation, and PPI of ASR in 68 Caucasian schizophrenia inpatients. Patients were also examined with the Positive and Negative Syndrome Scale.
Results: The 5-HT2AR A-1438G and T102C polymorphisms were in complete linkage disequilibrium. Patients carrying the T102C TT and the A-1438G AA allele show significantly higher PPI levels and a faster early habituation compared to all other variants. 5-HT2AR A-1438G and T102C genotype explained about 11% of the PPI and early habituation variance. In contrast, the 5-HT2AR H452Y polymorphism did not affect startle parameter.
Conclusions: Our findings suggest that PPI and habituation are modulated by 5-HT2AR A-1438G and T102C genotype in schizophrenia. Consequently, alterations within brain 5-HT2ARs may contribute to the PPI deficits in schizophrenia
Löslichkeit und Korrosionsverhalten von Eisen, Stahl, Molybdän, Niob, Tantal, Vanadium, Wolfram und Chrom in Bleischmelzen bei höheren Temperaturen
Im Temperaturbereich zwischen 35O°C und 11OO°C wurde die Eisenlöslichkeit von Armco-Eisen sowie die der Stähle X 7 Cr 14 und X 20 Cr 13 in Blei bestimmt. Außerdem wurde bei einer Temperatur von 65O°C die Eisenlöslichkeit der Stähle X 8 CrTi 17 und X 8 CrNb 17 in Blei ermittelt. Dabei wurde bei dem kohlenstoffreichen Stahl X 20 Cr 13 eine geringere Eisenlöslichkeit festgestellt als beim Stahl X 7 Cr 14 und bei Armco-Eisen. Beim Armco-Eisen zeigte die Temperaturabhängigkeit der Eisenlöslichkeit in Blei oberhalb und unterhalb von 91O°C unterschiedlichen Verlauf. Daraus wurde auf eine unterschiedliche Löslichkeit der und -Phase des Eisens in Blei geschlossen. Anschließend wurden die Proben auf ihr Korrosionsverhalten metallographisch untersucht. Im allgemeinen zeigten siean den Stellen stärkeren Korrosionsangriff, an denen sie unter Spannung beansprucht wurden. Bei einer Armco-Eisen Probe, die 520 Stunden lang bei einer Temperatur von 950 C mit Blei in Kontakt war, wurde interkristalline Korrosion festgestellt. Die Stähle X 8 CrTi 17 und X CrNb 17 wurden durch die Bleischmelze bei 65O°C während einer Versuchsdauer von 1000 Stunden in der gleichen Weise angegriffen. In beiden Stählen betrug die Eindringtiefe unter diesen Versuchsbedingungen etwa 38 m. Die hochschmelzenden Metalle, wie Molybdän, Niöb, Tantal, Vanadium und Wolfram, zeigten bis zu etwa 1000 keine Löslichkeit im flüssigen Blei. Die metallographische Untersuchung ergab jedoch, daß Vanadium durch Blei bei 95O°C korrodiert wurde. Bei 1110°Cwurde es schon bei einer Versuchsdauer von 20 stunden stark angegriffen. In Tantal traten bei 925°C nach 324 Stunden im gebogenen Teil der Probe Risse auf, die vermutlich auf Materialspannung zurückzuführen sind. Bei einer Temperatur von 985°C wurde Chrom während der Versuchsdauer von 233 Stunden durch Blei stark angegriffen
Verbal memory deficits are correlated with prefrontal hypometabolism in (18)FDG PET of recreational MDMA users
INTRODUCTION: 3,4-Methylenedioxymethamphetamine (MDMA, "ecstasy") is a recreational club drug with supposed neurotoxic effects selectively on the serotonin system. MDMA users consistently exhibit memory dysfunction but there is an ongoing debate if these deficits are induced mainly by alterations in the prefrontal or mediotemporal cortex, especially the hippocampus. Thus, we investigated the relation of verbal memory deficits with alterations of regional cerebral brain glucose metabolism (rMRGlu) in recreational MDMA users. METHODS: Brain glucose metabolism in rest was assessed using 2-deoxy-2-((18)F)fluoro-D-glucose positron emission tomography ((18)FDG PET) in 19 male recreational users of MDMA and 19 male drug-naïve controls. (18)FDG PET data were correlated with memory performance assessed with a German version of the Rey Auditory Verbal Learning Test. RESULTS: As previously shown, MDMA users showed significant impairment in verbal declarative memory performance. PET scans revealed significantly decreased rMRGlu in the bilateral dorsolateral prefrontal and inferior parietal cortex, bilateral thalamus, right hippocampus, right precuneus, right cerebellum, and pons (at the level of raphe nuclei) of MDMA users. Among MDMA users, learning and recall were positively correlated with rMRGlu predominantly in bilateral frontal and parietal brain regions, while recognition was additionally related to rMRGlu in the right mediotemporal and bihemispheric lateral temporal cortex. Moreover, cumulative lifetime dose of MDMA was negatively correlated with rMRGlu in the left dorsolateral and bilateral orbital and medial PFC, left inferior parietal and right lateral temporal cortex. CONCLUSIONS: Verbal learning and recall deficits of recreational MDMA users are correlated with glucose hypometabolism in prefrontal and parietal cortex, while word recognition was additionally correlated with mediotemporal hypometabolism. We conclude that memory deficits of MDMA users arise from combined fronto-parieto-mediotemporal dysfunction
Urinary concentrations of GHB and its novel amino acid and carnitine conjugates following controlled GHB administration to humans
Gamma-hydroxybutyrate (GHB) remains a challenging clinical/forensic toxicology drug. Its rapid elimination to endogenous levels mainly causes this. Especially in drug-facilitated sexual assaults, sample collection often occurs later than the detection window for GHB. We aimed to investigate new GHB conjugates with amino acids (AA), fatty acids, and its organic acid metabolites for their suitability as ingestion/application markers in urine following controlled GHB administration to humans. We used LC–MS/MS for validated quantification of human urine samples collected within two randomized, double-blinded, placebo-controlled crossover studies (GHB 50 mg/kg, 79 participants) at approximately 4.5, 8, 11, and 28 h after intake. We found significant differences (placebo vs. GHB) for all but two analytes at 4.5 h. Eleven hours post GHB administration, GHB, GHB-AAs, 3,4-dihydroxybutyric acid, and glycolic acid still showed significantly higher concentrations; at 28 h only GHB-glycine. Three different discrimination strategies were evaluated: (a) GHB-glycine cut-off concentration (1 µg/mL), (b) metabolite ratios of GHB-glycine/GHB (2.5), and (c) elevation threshold between two urine samples (> 5). Sensitivities were 0.1, 0.3, or 0.5, respectively. Only GHB-glycine showed prolonged detection over GHB, mainly when compared to a second time- and subject-matched urine sample (strategy c).ISSN:2045-232
- …