Subcellular localization and distribution of the reduced folate carrier in normal rat tissues

The reduced folate carrier (Rfc1; Slc19a1) mediated transport of reduced folates and antifolate drugs such as methotrexate (MTX) play an essential role in physiological folate homeostasis and MTX cancer chemotherapy. As no systematic reports are as yet available correlating Rfc1 gene expression and protein levels in all tissues crucial for folate and antifolate uptake, storage or elimination, we investigated gene and protein expression of rat Rfc1 (rRfc1) in selected tissues. This included the generation of a specific anti-rRfc1 antibody. Rabbits were immunised with isolated rRfc1 peptides producing specific anti-rRfc1 antiserum targeted to the intracellular C-terminus of the carrier. Using RT-PCR analysis, high rRfc1 transcript levels were detected in colon, kidney, brain, thymus, and spleen. Moderate rRfc1 gene expression was observed in small intestine, liver, bone marrow, lung, and testes whereas transcript levels were negligible in heart, skeletal muscle or leukocytes. Immunohistochemical analyses revealed strong carrier expression in the apical membrane of tunica mucosa epithelial cells of small intestine and colon, in the brush-border membrane of choroid plexus epithelial cells or in endothelial cells of small vessels in brain and heart. Additionally, high rRfc1 protein levels were localized in the basolateral membrane of renal tubular epithelial cells, in the plasma membrane of periportal hepatocytes, and sertoli cells of the testes. Taken together, our results demonstrated that rRfc1 is expressed almost ubiquitously but to very different levels. The predominant tissue distribution supports the essential role of Rfc1 in physiological folate homeostasis. Moreover, our results may contribute to understand antifolate pharmacokinetics and selected organ toxicity associated with MTX chemotherapy

The West against the rest? Democracy versus autocracy promotion in Venezuela

Venezuela provides a strong test case for the weakening of democracy and the strengthening of autocracy promotion. External actors are a key part of the domestic political game: the European Union and the United States (EUUS) promote ‘democracy by coercion’ and recognised Juan Guaidó as president, whereas China, Cuba and Russia (CCR) bolster the regime of Nicolás Maduro. A comparative foreign policy analysis argues that, firstly, EUUS sanctions have resulted in strengthening CCR's autocratic leverage and linkage; and secondly, the division ‘between the West and the Rest’ has posed an additional obstacle for a transition to democracy and national reconstructio

Temperature extremes of 2022 reduced carbon uptake by forests in Europe

The year 2022 saw record breaking temperatures in Europe during both summer and fall. Similar to the recent 2018 drought, close to 30% (3.0 million km2) of the European continent was under severe summer drought. In 2022, the drought was located in central and southeastern Europe, contrasting the Northern-centered 2018 drought. We show, using multiple sets of observations, a reduction of net biospheric carbon uptake in summer (56-62 TgC) over the drought area. Specific sites in France even showed a widespread summertime carbon release by forests, additional to wildfires. Partial compensation (32%) for the decreased carbon uptake due to drought was offered by a warm autumn with prolonged biospheric carbon uptake. The severity of this second drought event in 5 years suggests drought-induced reduced carbon uptake to no longer be exceptional, and important to factor into Europe’s developing plans for net-zero greenhouse gas emissions that rely on carbon uptake by forests

Seroepidemiological study on the spread of SARS-CoV-2 in Germany:

The SARS-CoV-2 coronavirus has spread rapidly across Germany. Infections are likely to be under-recorded in the notification data from local health authorities on laboratory-confirmed cases since SARS-CoV-2 infections can proceed with few symptoms and then often remain undetected. Seroepidemiological studies allow the estimation of the proportion in the population that has been infected with SARS-CoV-2 (seroprevalence) as well as the extent of undetected infections. The ‘CORONA-MONITORING bundesweit’ study (RKI-SOEP study) collects biospecimens and interview data in a nationwide population sample drawn from the German Socio-Economic Panel (SOEP). Participants are sent materials to self-collect a dry blood sample of capillary blood from their finger and a swab sample from their mouth and nose, as well as a questionnaire. The samples returned are tested for SARS-CoV-2 IgG antibodies and SARS-CoV-2 RNA to identify past or present infections. The methods applied enable the identification of SARS-CoV-2 infections, including those that previously went undetected. In addition, by linking the data collected with available SOEP data, the study has the potential to investigate social and health-related differences in infection status. Thus, the study contributes to an improved understanding of the extent of the epidemic in Germany, as well as identification of target groups for infection protection

Report from the EPAA workshop: In vitro ADME in safety testing used by EPAA industry sectors

AbstractThere are now numerous in vitro and in silico ADME alternatives to in vivo assays but how do different industries incorporate them into their decision tree approaches for risk assessment, bearing in mind that the chemicals tested are intended for widely varying purposes? The extent of the use of animal tests is mainly driven by regulations or by the lack of a suitable in vitro model. Therefore, what considerations are needed for alternative models and how can they be improved so that they can be used as part of the risk assessment process? To address these issues, the European Partnership for Alternative Approaches to Animal Testing (EPAA) working group on prioritisation, promotion and implementation of the 3Rs research held a workshop in November, 2008 in Duesseldorf, Germany. Participants included different industry sectors such as pharmaceuticals, cosmetics, industrial- and agro-chemicals. This report describes the outcome of the discussions and recommendations (a) to reduce the number of animals used for determining the ADME properties of chemicals and (b) for considerations and actions regarding in vitro and in silico assays. These included: standardisation and promotion of in vitro assays so that they may become accepted by regulators; increased availability of industry in vivo kinetic data for a central database to increase the power of in silico predictions; expansion of the applicability domains of in vitro and in silico tools (which are not necessarily more applicable or even exclusive to one particular sector) and continued collaborations between regulators, academia and industry. A recommended immediate course of action was to establish an expert panel of users, developers and regulators to define the testing scope of models for different chemical classes. It was agreed by all participants that improvement and harmonization of alternative approaches is needed for all sectors and this will most effectively be achieved by stakeholders from different sectors sharing data

Seroepidemiologische Studie zur bundesweiten Verbreitung von SARS-CoV-2 in Deutschland: Studienprotokoll von CORONA-MONITORING bundesweit (RKI-SOEP-Studie)

Das Coronavirus SARS-CoV-2 hat sich in kurzer Zeit bundesweit ausgebreitet. In den Meldedaten der Gesundheitsämter zu laborbestätigten Infektionsfällen ist von einer Untererfassung des Infektionsgeschehens auszugehen, da Infektionen häufig unentdeckt bleiben, zum Beispiel weil sie symptomarm verlaufen. In seroepidemiologischen Studien kann der Bevölkerungsanteil mit durchgemachter SARS-CoV-2-Infektion (Seroprävalenz) wie auch der Umfang unentdeckter Infektionen abgeschätzt werden. In der Studie CORONA-MONITORING bundesweit (RKI-SOEP-Studie) werden Bioproben und Befragungsdaten in einer deutschlandweiten Bevölkerungsstichprobe des Sozio-oekonomischen Panels (SOEP) erhoben. Den Teilnehmenden werden Materialien zur selbstständigen Gewinnung einer Trockenblutprobe aus Kapillarblut des Fingers und einer Abstrichprobe aus Mund und Nase sowie ein Fragebogen postalisch zugesendet. Die zurückgesendeten Proben werden auf SARS-CoV-2-IgG-Antikörper und SARS-CoV-2-RNA zur Identifikation einer durchgemachten oder aktuellen Infektion untersucht. Die eingesetzten Methoden ermöglichen es, auch solche SARS-CoV-2-Infektionen zu erkennen, die bislang unentdeckt blieben. Durch die Verknüpfung mit bereits vorhandenen SOEP-Daten hat die Studie das Potenzial, auch soziale und gesundheitsbezogene Unterschiede im Infektionsstatus zu untersuchen. So kann die Studie zu einem verbesserten Verständnis des Ausmaßes der Epidemie in Deutschland wie auch zur Identifikation von Zielgruppen für den Infektionsschutz beitragen