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Technetium (Tc) is an element originating mostly from the fission of ²³⁵U and ²³⁹Pu with a yield of 6%.¹ Therefore, ⁹⁹Tc is mainly found in high-level radioactive waste, e.g. from nuclear power or reprocessing plants.² The waste disposal is the subject of numerous studies due to the long half-life of many radionuclides (e.g. ⁹⁹Tc: 2.1 · 10⁵ years)¹ and their high radiotoxicity. One of the most widely accepted strategies is the deep geological underground repository. This approach relies on a multi-barrier system designed to minimize the risk of a worst-case scenario, where water intrusion could lead to the corrosion of the waste canister and the subsequent release of radionuclides. For the long-term safety, including the construction of effective barriers, it is essential to study the interaction of radionuclides with the various minerals present in the repository at a fundamental level. Tc poses a particular challenge due to its complex redox chemistry high mobility in its oxidized form TcO₄¯, under oxidising conditions. However, Tc migration decreases significantly when Tc(VII) is reduced to Tc(IV), as it then forms precipitates or becomes immobilized by mineral surfaces such as Fe(II) minerals.³ Vivianite (Fe₃(PO₄)₂ · 8 H₂O) is a naturally occurring Fe(II) mineral under reducing conditions⁵ and can be formed by microorganisms.⁶ Phosphate phases are already being considered as an immobilisation matrix for other radionuclides relevant in deep geological repositories (e.g. ²³⁵U, ²³⁷Np, ²³⁹Pu, ²⁴³Am).⁷ ⁸ This study investigates the retention of Tc by synthetic vivianite particles as a function of pH, Tc concentration and ionic strength on a macroscopic and molecular scale. In addition, Tc(IV) reoxidation experiments were performed.⁴ The synthesis of vivianite was carried out by precipitation from a solution mixture of an iron(II) sulphate and ammonium hydrogen phosphate, as described by Roldán et al..⁹ The product was characterised by Raman microscopy, Mössbauer spec

Technetium (Tc) is an element originating mostly from the fission of ²³⁵U and ²³⁹Pu with a yield of 6%.¹ Therefore, ⁹⁹Tc is mainly found in high-level radioactive waste, e.g. from nuclear power or reprocessing plants.² The waste disposal is the subject of numerous studies due to the long half-life of many radionuclides (e.g. ⁹⁹Tc: 2.1 · 10⁵ years)¹ and their high radiotoxicity. One of the most accepted concepts is the deep geological underground repository. A multiple barrier system is planned to reduce the risk of a worst-case scenario, when water ingress could induce the corrosion of the canister containing the waste and, thus, radionuclide release. For the long-term safety, including the construction of effective barriers, the interaction of the radionuclides with different minerals present in the repository needs to be studied at a fundamental level. Tc shows a complex redox chemistry and is considered very mobile compared to cationic radionuclides, due to the presence of the negatively charged TcO₄⁻ under oxidising conditions. However, Tc migration decreases when Tc(VII) is reduced to Tc(IV) since it forms precipitates or is immobilized by mineral surfaces, e.g. with Fe(II) minerals (Fig. 1).³ Vivianite (Fe₃(PO₄)₂ · 8 H₂O) is a naturally occurring Fe(II) mineral under reducing conditions⁵ and can be formed by microorganisms.⁶ Phosphate phases are already being considered as an immobilisation matrix for other radionuclides relevant in deep geological repositories (e.g. ²³⁵U, ²³⁷Np, ²³⁹Pu, ²⁴³Am).⁷ ⁸ This study investigates the retention of Tc by synthetic vivianite particles as a function of pH, Tc concentration and ionic strength on a macroscopic and molecular scale. In addition, Tc(IV) reoxidation experiments were performed.⁴ The synthesis of vivianite was carried out by precipitation from a solution mixture of an iron(II) sulphate and ammonium hydrogen phosphate, as described by Roldán et al..⁹ The product was characterised by Raman microscopy, Mössbauer spec

Technetium-99 (⁹⁹Tc) ist ein langlebiges Spaltprodukt (2,13∙10⁵ Jahre) von Uran-235 (²³⁵U) und Plutonium-239 (²³⁹Pu) und daher von großer Bedeutung für die langfristig sichere Entsorgung von radioaktiven Abfällen aus Kern-kraftwerken. Die Migration von Tc in der Umwelt wird stark von den Redoxbedingungen beeinflusst, da Tc in verschiedenen Oxidationsstufen vorliegen kann. In der Umgebung eines Endlagers dürfte Tc unter oxidierenden Bedingungen hauptsächlich als Tc(VII) und unter reduzierenden Bedin-gungen als Tc(IV) auftreten. Es ist bekannt, dass das Anion Pertechnetat (Tc(VII)O₄ ⁻) kaum mit mineralischen Oberflächen interagiert, was wiederum seine Migration im Grundwasser und seinen Eintritt in die Biosphäre begünstigt. Im Gegensatz dazu schränkt die Bildung von Tc(IV) die Migration von Tc ein, da es einen schwerlöslichen Feststoff (TcO₂) und/oder Spezies bildet, deren Wechselwirkung mit Mineralien günstiger ist. In vergangenen Untersuchungen lag der Fokus auf der Reduktion von Tc(VII) zu Tc(IV) durch verschiedene Reduktionsmittel wie Fe(II), Sn(II) oder S(-II), die entweder in Lösung vorliegen, an mineralischen Strukturen beteiligt sind (Pearce et al.) oder metabolisch durch mikrobielle Kaskaden induziert werden (Newsome et al.). Die meisten der veröffentlichten Studien konzentrierten sich auf binäre Systeme, d. h. auf die Untersuchung der Wechselwirkung von Tc mit einem bestimmten Reduktionsmittel. Die Umwelt ist jedoch ein komplexes System, in dem verschiedene Komponenten oft voneinander abhängen und sich gegenseitig beeinflussen. Daher ist die Tc-Migration anfällig und variiert je nach Umweltbedingungen und sollte nicht isoliert untersucht werden. Die Arbeiten der vom BMBF geförderte Nachwuchsforschungsgruppe TecRad (TecRad 2023) zielen darauf ab die Tc-Chemie aus einer breiteren Perspektive zu analysieren. Daher untersuchen wir das biogeochemische Verhalten von Tc mit i) Mikroorganismen, ii) Metaboliten, und iii) Fe(II)-Mineralen. Weiterhin möchten wir die We

Migraine is a severe neurovascular disorder of which the pathophysiology is not yet fully understood. Besides the role of inflammatory mediators that interact with the trigeminovascular system, cyclic fluctuations in sex steroid hormones are involved in the sex dimorphism of migraine attacks. In addition, the pituitary-derived hormone prolactin and the hypothalamic neuropeptide oxytocin have been reported to play a modulating role in migraine and contribute to its sex-dependent differences. The current narrative review explores the relationship between these two hormones and the pathophysiology of migraine. We describe the physiological role of prolactin and oxytocin, its relationship to migraine and pain, and potential therapies targeting these hormones or their receptors. In summary, oxytocin and prolactin are involved in nociception in opposite ways. Both operate at peripheral and central levels, however, prolactin has a pronociceptive effect, while oxytocin appears to have an antinociceptive effect. Therefore, migraine treatment targeting prolactin should aim to block its effects using prolactin receptor antagonists or monoclonal antibodies specifically acting at migraine-pain related structures. This action should be local in order to avoid a decrease in prolactin levels throughout the body and associated adverse effects. In contrast, treatment targeting oxytocin should enhance its signalling and antinociceptive effects, for example using intranasal administration of oxytocin, or possibly other oxytocin receptor agonists. Interestingly, the prolactin receptor and oxytocin receptor are co-localized with estrogen receptors as well as calcitonin gene-related peptide and its receptor, providing a positive perspective on the possibilities for an adequate pharmacological treatment of these nociceptive pathways. Nevertheless, many questions remain to be answered. More particularly, there is insufficient data on the role of sex hormones in men and the correct dosing ac

Technetium-99 (⁹⁹Tc) is a long-lived fission product (2.13∙10⁵ years) of uranium-235 (²³⁵U) and plutonium-239 (²³⁹Pu) and therefore, of great concern for the long-term safe management of nuclear waste. The migration of Tc in the environment is highly influenced by the redox conditions, since Tc may be present in various oxidation states. Under environmental conditions, Tc is expected to mainly occur as Tc(VII) under oxidizing conditions and as Tc(IV) under reducing conditions. The anion pertechnetate (Tc(VII)O₄⁻) is known to barely interact with mineral surfaces; this, in turn, enhances its migration in groundwater and favors its entry in the biosphere. On the contrary, the formation of Tc(IV) limits the migration of Tc since it forms a low soluble solid (TcO2) and/or species whose interaction with minerals is more favorable. In the last decades Tc migration has been focused on the reduction of Tc(VII) to Tc(IV) by various reductants, such as Fe(II), Sn(II) or S(-II) either present in solution, taking part in mineral structures, [1] or metabolically induced by microbial cascades [2]. Most of the published studies have been focused on binary systems i.e., studies of the interaction of Tc with a given reductant. However, the environment is a complex system where different components often depend on and modify each other. Thus, Tc migration is susceptible and varies upon environmental conditions and should not be studied in an isolated manner. The young investigator group TecRad [3], funded by the German Federal Ministry of Education and Research, aims at analyzing Tc chemistry from a wider perspective. Our goal is to study the biogeochemical behavior of Tc when it interacts with: i) microorganisms, ii) metabolites, iii) Fe(II) minerals, and iv) Fe(II) minerals in presence of metabolites. An important part of this project deals with implementing new spectro-electrochemical methods to monitor in situ the behavior of Tc in solution and at interfaces as a function of the

Technetium-99 (⁹⁹Tc) is a long-lived fission product (2.13∙10⁵ years) of uranium-235 (²³⁵U) and plutonium-239 (²³⁹Pu) and therefore, of great concern for the long-term safe management of nuclear waste. The migration of Tc in the environment is highly influenced by the redox conditions since Tc may be present in various oxidation states. Depending on the chemical properties of environmental relevant systems Tc is expected to mainly occur as Tc(VII) and as Tc(IV) under oxidizing and reducing conditions, respectively. The anion pertechnetate (Tc(VII)O₄⁻) is known to barely interact with mineral surfaces; this, in turn, enhances its migration in groundwater and favours its entry into the biosphere. On the contrary, the formation of Tc(IV) limits the migration of Tc since it forms a low soluble solid (TcO₂) and/or species whose interaction with minerals is more favourable. In the last decades Tc migration has been focused on the reduction of Tc(VII) to Tc(IV) by various reductants, such as Fe(II), Sn(II) or S(-II) either present in solution, taking part in mineral structures, (Pearce et al., 2019) or metabolically induced by microbial cascades (Newsome et al., 2014). We have studied the immobilization of Tc by various Fe(II)-containing phases: Fe²⁺ pre-sorbed on alumina nanoparticles (Mayordomo et al., 2020), Fe(II)-Al(III) layered double hydroxide (Mayordomo et al., 2021), and Fe(II) sulfides (Rodriguez et al., 2020; Rodríguez et al., 2021). We have combined sorption experiments, with microscopic and spectroscopic techniques (scanning electron microscopy, Raman microscopy, X-ray photoelectron spectroscopy, infrared spectroscopy, and X-ray absorption spectroscopy) to elucidate the mechanisms responsible of Tc(VII) reductive immobilization. Those works have been focused on binary systems i.e., studies of the interaction of Tc with a given reductant. However, the environment is a complex system where different components often depend on and modify each other. Thus, Tc migr

Technetium (Tc, Ordnungszahl 43) ist das leichteste Element, welches keine stabilen Isotope besitzt. Das Hauptvorkommen von Tc stammt aus anthropogen Quellen, wie abgebrannten Brennstoffen aus Kernkraftwerken, Atomwaffentests, sowie nuklearen Unfällen. Das Radionuklid Tc-99 entsteht hierbei als ein Spaltprodukt mit rund 6% Ausbeute und ist somit im nuklearen Abfall vorhanden, welcher im geologischen Tiefenendlager für 1Mio Jahre gelagert werden soll. Zusätzlich wird Tc-99m als Kontrastmittel in der Medizindiagnostik angewendet, welches zu Tc-99 zerfällt und in das Abwasser gelangt. Aus diesen Gründen besteht die Notwendigkeit, die Interaktion von Tc mit Mineralen zu untersuchen, um Möglichkeiten zur immobilisierung zu finden. Das in Wasser mobile Pertechnetat (Tc(VII)O₄⁻) kann durch Sorption und Reduktion zu schwerlöslichem TcO₂ an Fe(II)-haltigen Mineralen zurückgehalten werden. In dieser Arbeit wurde die Retention an Vivianit (Fe₃(PO₄)₂·8 H₂O) untersucht. Das türkisfarbene Mineral wurde erfolgreich über eine Präzipitation unter Inertgas synthetisch hergestellt. Mittels XRD und Raman konnte die Übereinstimmung mit Referenzspektren für Vivianit bei dem Gleichwichts-pH-Wert pH 6,7 festgestellt werden. Bei einer Verringerung des pH-Wertes auf pH 5 ist Vivianit weiterhin stabil, während bei einem pH-Wert von pH 12 eine Phasenänderung zu Amakinit (Fe(II)(OH)₂) stattfindet. TcO₄− kann durch suspendiertes Vivianit aus der Lösung bei pH 8 im Verlauf von 20 d entfernt werden, während bei pH 6,5 die Immobilisierung nicht stattfindet. Mit steigender Konzentration an Vivianit in der Lösung steigt auch die Entfernung von TcO₄− bei pH 6,5. Bei pH 8 hingegen sinkt die Entfernung mit größerer Mineralkonzentration bei 3 d Sorptionszeit, wobei nach 10 d Tc in der Lösung nicht mehr detektierbar ist. Vermutet wird die Bildung löslicher Tc-phosphate. Mit steigendem pH-Wert steigt die Immobilisierung von Tc aus der Lösung. Bei niedrigen pH-Werten ist die geringe Sorption auf die hohe Lö

Psychotic experiences have been proposed to lie on a spectrum, ranging from subclinical experiences to treatment-resistant schizophrenia. We aimed to characterize functional connectivity and brain network characteristics in relation to the schizophrenia spectrum and bipolar disorder with psychosis to disentangle neural correlates to psychosis. Additionally, we studied antipsychotic medication and lithium effects on network characteristics. We analyzed functional connectivity strength and network topology in 487 resting-state functional MRI scans of individuals with schizophrenia spectrum disorder (SCZ), bipolar disorder with a history of psychotic experiences (BD), treatment-naïve subclinical psychosis (SCP), and healthy controls (HC). Since differences in connect

Radiation therapy is an important and effective treatment option for prostate cancer, but high-risk patients are prone to relapse due to radioresistance of cancer cells. Molecular mechanisms that contribute to radioresistance are not fully understood. Novel computational strategies are needed to identify radioresistance driver genes from hundreds of gene copy number alterations. We developed a network-based approach based on lasso regression in combination with network propagation for the analysis of prostate cancer cell lines with acquired radioresistance to identify clinically relevant marker genes associated with radioresistance in prostate cancer patients. We analyzed established radioresistant cell lines of the prostate cancer cell lines DU145 and LNCaP and compared their gene copy number and expression profiles to their radiosensitive parental cells. We found that radioresistant DU145 showed much more gene copy number alterations than LNCaP and their gene expression profiles were highly cell line specific. We learned a genome-wide prostate cancer-specific gene regulatory network and quantified impacts of differentially expressed genes with directly underlying copy number alterations on known radioresistance marker genes. This revealed several potential driver candidates involved in the regulation of cancer-relevant processes. Importantly, we found that ten driver candidates from DU145 (ADAMTS9, AKR1B10, CXXC5, FST, FOXL1, GRPR, ITGA2, SOX17, STARD4, VGF) and four from LNCaP (FHL5, LYPLAL1, PAK7, TDRD6) were able to distinguish irradiated prostate cancer patients into early and late relapse groups. Moreover, in-depth in vitro validations for VGF (Neurosecretory protein VGF) showed that siRNA-ediated gene silencing increased the radiosensitivity of DU145 and LNCaP cells. Our computational approach enabled to predict novel radioresistance driver gene candidates. Additional preclinical and clinical studies are required to further validate the role of VGF and other