Workflow for the identification of biotransformation products of amine-containing psychotropic drugs in the aquatic environment

Pharmaceuticals are continuously discarded Pharmaceuticals are continuously discarded into the aquatic system through wastewater treatment plants (WWTPs). The microbial degradation of these organic micropollutants and formation of transformation products (TPs) under aerobic conditions is the fundamental process for their elimination. It is of paramount importance to understand the microbial metabolic pathways so as to obtain knowledge of how fast micropollutants degraded and to assess the exposure to their potential TPs as they can be more polar and consequently environmentally persistent. In this study, batch reactors seeded with activated sludge from the WWTP of Athens were set up to assess biotic, abiotic and sorption losses of selective psychotropic drugs, containing amine moieties. Biodegradation and transformation products were identified using liquid chromatography quadrupole-time-offlight mass spectrometry (LC-QToF-MS). A workflow for target, suspect and non-target screening was developed. Data treatment was performed by using metabolite tools accompanying Bruker’s maxis impact ESI-QToF-MS and the structure elucidation of the candidate transformation products was based on accurate mass and isotopic pattern measurements by HRMS and tentative interpretation of MS/MS spectra. Finally four biotransformation products were identified for both lidocaine and ephedrine. Despite the structure similarities, different degradation constants were calculated for each compound

Biotransformation of citalopram: Insights from identification of transformation products by LC-QToF-MS

Biodegradation is considered to be the key process for the elimination of the majority of pharmaceuticals in the environment. During wastewater treatment or once they are disposed in the aquatic environment, pharmaceuticals may transformed to new, structurally-related compounds which are called transformation products (TPs). Since most of these compounds are unknowns, their identification is essential not only to provide a comprehensive risk assessment on micropollutants in the environment, but also to design improved removal technologies for (pseudo)persistent trace contaminants. In this study, batch reactors seeded with activated sludge from the WWTP of Athens were set up to assess biotic, abiotic and sorption losses of a SSRI drug, citalopram. TPs were identified by reversed-phase liquid chromatography quadrupole-time-of-flight mass spectrometry (RPLC-QToF-MS). Hydrophilic interaction liquid chromatography (HILIC) was also used as a complementary, orthogonal, technique for the identified TPs, instead of NMR. A workflow for suspect and non-target screening was developed. A suspect list of possible TPs was compiled by literature and in silico prediction tools (EAWAG-BBD Pathway Prediction System and Bruker’s Metabolite Predict). Structure elucidation of TPs was based on accurate mass and isotopic pattern measurements and interpretation of MS/MS spectra by the observed fragmentation pattern and library-spectrum match. In total, thirteen TPs were identified. Four out of them were fully identified and confirmed by reference standards (desmethylcitalopram, citalopram amide, citalopram carboxylic acid and 3-oxo-citalopram). A probable structure based on diagnostic evidence and tentative candidates were proposed for the additional five and four TPs, respectively. Finally, a transformation pathway based on the identified compounds was presented

Targeted determination of more than 1500 micropollutants & transformation products in wastewater samples by liquid chromatography quadrupole-time-of-flight mass spectrometry with an accurate-mass database

High resolution mass spectrometry has dramatically improved the possibilities of the environmental analysis. The present study describes the development of an analytical method, based on liquid chromatography quadrupole-time-of-flight mass spectrometry (LC–QToF-MS) for the target determination of more than 1500 contaminants of emerging concern (CECs) and transformation products (TPs) including, among others, pharmaceuticals, illicit drugs, personal care products, pesticides, industrial chemicals, and sweeteners in wastewater. Analytes were extracted from wastewater samples by mixed mode solid-phase extraction, and data were acquired through broad-band Collision Induced Dissociation (bbCID) mode, providing MS and MS/MS spectra, simultaneously, in both positive and negative ionization mode (two separate runs). The in-house mass spectral database was built by injection of standard solution of the analytes and it includes information of the retention time, parent ions and adducts, as well as fragment ions. The raw data were analyzed with Bruker Target Analysis 1.3 software. Retention time, accurate mass of the precursor ion and adducts, isotopic pattern, in combination with absence of the peak in the procedural blank were the parameters used for confirmation of the target compounds. Experimental fragment ions were also considered, along with the ion ratio, intensity and isotopic pattern. Furthermore, semi-quantitation of these contaminants was possible. The method herein presented, in addition of providing accurate information about the presence of a large number of relevant substances, has the advantage that the data generated can be further processed for suspect and non-target screening, expanding the information on the samples. An important advantage of this method is that retrospective investigation of the data is available to look for the presence of additional CECs and their TPs, which were not considered at the time of the analysi

Cheese whey processing: integrated biorefinery concepts and emerging food applications

Cheese whey constitutes one of the most polluting by-products of the food industry, due to its high organic load. Thus, in order to mitigate the environmental concerns, a large number of valorization approaches have been reported; mainly targeting the recovery of whey proteins and whey lactose from cheese whey for further exploitation as renewable resources. Most studies are predominantly focused on the separate implementation, either of whey protein or lactose, to configure processes that will formulate value-added products. Likewise, approaches for cheese whey valorization, so far, do not exploit the full potential of cheese whey, particularly with respect to food applications. Nonetheless, within the concept of integrated biorefinery design and the transition to circular economy, it is imperative to develop consolidated bioprocesses that will foster a holistic exploitation of cheese whey. Therefore, the aim of this article is to elaborate on the recent advances regarding the conversion of whey to high value-added products, focusing on food applications. Moreover, novel integrated biorefining concepts are proposed, to inaugurate the complete exploitation of cheese whey to formulate novel products with diversified end applications. Within the context of circular economy, it is envisaged that high value-added products will be reintroduced in the food supply chain, thereby enhancing sustainability and creating “zero waste” processes

AC-feasible Local Flexibility Market with Continuous Trading

This paper proposes a novel continuous Local Flexibility Market where active power flexibility located in the distribution system can be traded. The market design engages the Market Operator, the Distribution System Operator and Market Participants with dispatchable assets. The proposed market operates in a single distribution system and considers network constraints via AC network sensitivities, calculated at an initial network operating point. Trading is possible when AC network constraints are respected and when anticipated network violations are alleviated or resolved. The implementation allows for partial bid matching and is computationally light, therefore, suitable for continuous trading applications. The proposed design is thoroughly described and is demonstrated in a test distribution system. It is shown that active power trading in the proposed market design can lead to resolution of line overloads.Comment: In proceedings of the 11th Bulk Power Systems Dynamics and Control Symposium (IREP 2022), July 25-30, 2022, Banff, Canad

Gata3 targets Runx1 in the embryonic haematopoietic stem cell niche.

Runx1 is an important haematopoietic transcription factor as stressed by its involvement in a number of haematological malignancies. Furthermore, it is a key regulator of the emergence of the first haematopoietic stem cells (HSCs) during development. The transcription factor Gata3 has also been linked to haematological disease and was shown to promote HSC production in the embryo by inducing the secretion of important niche factors. Both proteins are expressed in several different cell types within the aorta-gonads-mesonephros (AGM) region, in which the first HSCs are generated; however, a direct interaction between these two key transcription factors in the context of embryonic HSC production has not formally been demonstrated. In this current study, we have detected co-localisation of Runx1 and Gata3 in rare sub-aortic mesenchymal cells in the AGM. Furthermore, the expression of Runx1 is reduced in Gata3 -/- embryos, which also display a shift in HSC emergence. Using an AGM-derived cell line as a model for the stromal microenvironment in the AGM and performing ChIP-Seq and ChIP-on-chip experiments, we demonstrate that Runx1, together with other key niche factors, is a direct target gene of Gata3. In addition, we can pinpoint Gata3 binding to the Runx1 locus at specific enhancer elements which are active in the microenvironment. These results reveal a direct interaction between Gata3 and Runx1 in the niche that supports embryonic HSCs and highlight a dual role for Runx1 in driving the transdifferentiation of haemogenic endothelial cells into HSCs as well as in the stromal cells that support this process.This work was supported by an Intermediate Fellowship (K.O.) and a Junior Fellowship (S.R.F.) from the Kay Kendall Leukaemia Fund, a British Society for Haematology Early Stage Investigator Fellowship (K.O.) as well as funding from Bloodwise (N.K.W. and B.G.), MRC (N.K.W. and B.G.) and the Wellcome Trust (N.K.W. and B.G.). MdB is funded by a programme in the MRC Molecular Hematology Unit Core award (Grant number: MC_UU_12009/2). Core facilities are supported by Strategic Award WT100140, equipment grant 093026 and centre grant MR/K017047/1

Coxsackievirus and adenovirus receptor expression in human endometrial adenocarcinoma: possible clinical implications

The coxsackievirus and adenovirus receptor (CAR) is a crucial receptor for the entry of both coxsackie B viruses and adenoviruses into host cells. CAR expression on tumor cells was reported to be associated with their sensitivity to adenoviral infection, while it was considered as a surrogate marker for monitoring and/or predicting the outcome of adenovirus-mediated gene therapy. The aim of the present study was to evaluate the clinical significance of CAR expression in endometrial adenocarcinoma. CAR expression was assessed immunohistochemically in tumoral samples of 41 endometrial adenocarcinoma patients and was statistically analyzed in relation to various clinicopathological parameters, tumor proliferative capacity and patient survival. CAR positivity was noted in 23 out of 41 (56%) endometrial adenocarcinoma cases, while high CAR expression in 8 out of 23 (35%) positive ones. CAR intensity of immunostaining was classified as mild in 11 (48%), moderate in 10 (43%) and intense in 2 (9%) out of the 23 positive cases. CAR positivity was significantly associated with tumor histological grade (p = 0.036), as well differentiated tumors more frequently demonstrating no CAR expression. CAR staining intensity was significantly associated with tumor histological type (p = 0.016), as tumors possessing squamous elements presented more frequently intense CAR immunostaining. High CAR expression showed a trend to be correlated with increased tumor proliferative capacity (p = 0.057). Patients with tumors presenting moderate or intense CAR staining intensity were characterized by longer survival times than those with mild one; however, this difference did not reach statistical significance. These data reveal, for the first time, the expression of CAR in clinical material obtained from patients with endometrial adenocarcinoma in relation to important clinicopathological parameters for their management. As CAR appears to modulate the proliferation and characteristics of cancer cells, its expression could be considered of possible clinical importance for future (gene) therapy applications