Landbouweffectrapport Romeins Aquaduct Tongeren (Tongeren, provincie Limburg)

Het Romeins aquaduct in Tongeren is een uniek monument. Een gedeelte van het aquaduct (het deel op de Beukenberg) is al langer beschermd. Ten tijde van deze studie was er eveneens een beschermingsdossier in opmaak om ook een ander gedeelte te beschermen als archeologisch monument. De restanten van het aquaduct worden immers aangetast door bodemerosie, vooral veroorzaakt door de intensieve landbouw in het gebied. Het beschermingsdossier op zich zou weinig beperkingen opleggen aan de landbouw. Het doel van deze studie was dan ook enerzijds om dit dossier te onderbouwen, maar ook en vooral om te kijken of er een draagvlak aanwezig is om verder te gaan dan een bescherming die louter op papier bestaat. Binnen de perimeter van het aquaduct bevinden er zich 20,25ha landbouwgronden, die deel uitmaken van 38 percelen en in gebruik zijn bij 20 gebruikers. Het gaat om een erg waardevol landbouwgebied, vooral door de goede perceelsstructuren (een gevolg van ruilverkaveling Widooie), de algemene bemestingsnormen en de vruchtbare leemgronden. Het grondgebruik bestaat hoofdzakelijk uit akkerbouw, met in mindere mate fruitteelt en grove groenteteelt. Grasland komt slechts in zeer beperkte mate voor. De landbouwbedrijven met gronden in het gebied zijn in hoofdzaak akkerbouw- en vleesveebedrijven, met ook enkele fruittelers en varkenshouders. De meeste bedrijven zijn vrij grote, dynamische ondernemingen, al zitten er ook een paar hobbybedrijven tussen. De landbouwers zijn overwegend nog vrij jong of hebben opvolgers voor hun bedrijf. Slechts twee of drie bedrijven kunnen als uitbollend worden beschouwd. Deze factoren samen maken het moeilijk om maatregelen te nemen om het aquaduct te beschermen. De landbouwers zelf zijn overwegend ook vrij sceptisch en zien vaak het nut er niet van in. Voor de bescherming van het aquaduct zou het ideale scenario zijn dat de overheid de gronden binnen de perimeter zou kunnen verwerven en dat de percelen onder grasland zouden worden gelegd. Dit lijkt op dit moment echter weinig realistisch. Immers is er slechts één bedrijf op vrij korte termijn bereid om zijn gronden te verkopen. Nog enkele bedrijven zijn eventueel bereid om hun gronden in het gebied te ruilen tegen andere gronden in de omgeving, al dan niet via een lokale grondenbank. Hierbij blijft echter het probleem dat eerst in de omgeving grond verworven moet kunnen worden alvorens men kan ruilen. Bovendien hebben deze bedrijven de betrokken gronden meestal alleen maar in pacht en niet in eigendom, wat de ruilmogelijkheden sterk beperkt. Het inzetten van beheersovereenkomsten om de achteruitgang van het aquaduct tegen te gaan biedt allicht meer mogelijkheden. Vooral de beheersovereenkomsten erosiebestrijding zijn mogelijk interessant. Verschillende landbouwers bleken geïnteresseerd om hierin mee te stappen. Een gerichte inzet van deze beheersovereenkomsten, geconcentreerd op het gebied, zou mogelijk de verdere achteruitgang van het aquaduct kunnen afremmen. Toch zal men er rekening mee moeten houden dat de effectieve bescherming van het aquaduct een werk van lange adem zal zijn

Segregation of myoblast fusion and muscle-specific gene expression by distinct ligand-dependent inactivation of GSK-3β

Myogenic differentiation involves myoblast fusion and induction of muscle-specific gene expression, which are both stimulated by pharmacological (LiCl), genetic, or IGF-I-mediated GSK-3β inactivation. To assess whether stimulation of myogenic differentiation is common to ligand-mediated GSK-3β inactivation, myoblast fusion and muscle-specific gene expression were investigated in response to Wnt-3a. Moreover, crosstalk between IGF-I/GSK-3β/NFATc3 and Wnt/GSK-3β/β-catenin signaling was assessed. While both Wnt-3a and LiCl promoted myoblast fusion, muscle-specific gene expression was increased by LiCl, but not by Wnt-3a or β-catenin over-expression. Furthermore, LiCl and IGF-I, but not Wnt-3a, increased NFATc3 transcriptional activity. In contrast, β-catenin-dependent transcriptional activity was increased by Wnt-3a and LiCl, but not IGF-I. These results for the first time reveal a segregated regulation of myoblast fusion and muscle-specific gene expression following stimulation of myogenic differentiation in response to distinct ligand-specific signaling routes of GSK-3β inactivation

Harmonized human biomonitoring in European children, teenagers and adults: EU-wide exposure data of 11 chemical substance groups from the HBM4EU Aligned Studies (2014-2021)

As one of the core elements of the European Human Biomonitoring Initiative (HBM4EU) a human biomonitoring (HBM) survey was conducted in 23 countries to generate EU-wide comparable HBM data. This survey has built on existing HBM capacity in Europe by aligning national or regional HBM studies, referred to as the HBM4EU Aligned Studies. The HBM4EU Aligned Studies included a total of 10,795 participants of three age groups: (i) 3,576 children aged 6-12 years, (ii) 3,117 teenagers aged 12-18 years and (iii) 4,102 young adults aged 20-39 years. The participants were recruited between 2014 and 2021 in 11-12 countries per age group, geographically distributed across Europe. Depending on the age group, internal exposure to phthalates and the substitute DINCH, halogenated and organophosphorus flame retardants, per- and polyfluoroalkyl substances (PFASs), cadmium, bisphenols, polycyclic aromatic hydrocarbons (PAHs), arsenic species, acrylamide, mycotoxins (deoxynivalenol (total DON)), benzophenones and selected pesticides was assessed by measuring substance specific biomarkers subjected to stringent quality control programs for chemical analysis. For substance groups analyzed in different age groups higher average exposure levels were observed in the youngest age group, i.e., phthalates/DINCH in children versus teenagers, acrylamide and pesticides in children versus adults, benzophenones in teenagers versus adults. Many biomarkers in teenagers and adults varied significantly according to educational attainment, with higher exposure levels of bisphenols, phthalates, benzophenones, PAHs and acrylamide in participants (from households) with lower educational attainment, while teenagers from households with higher educational attainment have higher exposure levels for PFASs and arsenic. In children, a social gradient was only observed for the non-specific pyrethroid metabolite 3-PBA and di-isodecyl phthalate (DiDP), with higher levels in children from households with higher educational attainment. Geographical variations were seen for all exposure biomarkers. For 15 biomarkers, the available health-based HBM guidance values were exceeded with highest exceedance rates for toxicologically relevant arsenic in teenagers (40%), 3-PBA in children (36%), and between 11 and 14% for total DON, Sigma (PFOA + PFNA + PFHxS + PFOS), bisphenol S and cadmium. The infrastructure and harmonized approach succeeded in obtaining comparable European wide internal exposure data for a prioritized set of 11 chemical groups. These data serve as a reference for comparison at the global level, provide a baseline to compare the efficacy of the European Commission's chemical strategy for sustainability and will give leverage to national policy makers for the implementation of targeted measures

Harmonized human biomonitoring in European children, teenagers and adults: EU-wide exposure data of 11 chemical substance groups from the HBM4EU Aligned Studies (2014–2021)

As one of the core elements of the European Human Biomonitoring Initiative (HBM4EU) a human biomonitoring (HBM) survey was conducted in 23 countries to generate EU-wide comparable HBM data. This survey has built on existing HBM capacity in Europe by aligning national or regional HBM studies, referred to as the HBM4EU Aligned Studies. The HBM4EU Aligned Studies included a total of 10,795 participants of three age groups: (i) 3,576 children aged 6–12 years, (ii) 3,117 teenagers aged 12–18 years and (iii) 4,102 young adults aged 20–39 years. The participants were recruited between 2014 and 2021 in 11–12 countries per age group, geographically distributed across Europe. Depending on the age group, internal exposure to phthalates and the substitute DINCH, halogenated and organophosphorus flame retardants, per- and polyfluoroalkyl substances (PFASs), cadmium, bisphenols, polycyclic aromatic hydrocarbons (PAHs), arsenic species, acrylamide, mycotoxins (deoxynivalenol (total DON)), benzophenones and selected pesticides was assessed by measuring substance specific biomarkers subjected to stringent quality control programs for chemical analysis. For substance groups analyzed in different age groups higher average exposure levels were observed in the youngest age group, i.e., phthalates/DINCH in children versus teenagers, acrylamide and pesticides in children versus adults, benzophenones in teenagers versus adults. Many biomarkers in teenagers and adults varied significantly according to educational attainment, with higher exposure levels of bisphenols, phthalates, benzophenones, PAHs and acrylamide in participants (from households) with lower educational attainment, while teenagers from households with higher educational attainment have higher exposure levels for PFASs and arsenic. In children, a social gradient was only observed for the non-specific pyrethroid metabolite 3-PBA and di-isodecyl phthalate (DiDP), with higher levels in children from households with higher educational attainment. Geographical variations were seen for all exposure biomarkers. For 15 biomarkers, the available health-based HBM guidance values were exceeded with highest exceedance rates for toxicologically relevant arsenic in teenagers (40%), 3-PBA in children (36%), and between 11 and 14% for total DON, Σ (PFOA + PFNA + PFHxS + PFOS), bisphenol S and cadmium. The infrastructure and harmonized approach succeeded in obtaining comparable European wide internal exposure data for a prioritized set of 11 chemical groups. These data serve as a reference for comparison at the global level, provide a baseline to compare the efficacy of the European Commission's chemical strategy for sustainability and will give leverage to national policy makers for the implementation of targeted measures

Wnt5b stimulates adipogenesis by activating PPARgamma, and inhibiting the beta-catenin dependent Wnt signaling pathway together with Wnt5a.

Correct Wnt signaling is required for adipogenesis and alterations occur in Type 2 diabetes mellitus (T2DM). Gene expression studies showed that beta-catenin independent Wnt5b was down-regulated in T2DM preadipocytes, while its paralog Wnt5a was unchanged. Our study aimed at defining the expression profile and function of Wnt5a and Wnt5b during adipogenesis by determining their effect on aP2 and PPARgamma expression and assessing the level of beta-catenin translocation in mouse 3T3-L1 preadipocytes. Additionally, we explored the effect on adipogenic capacity by Wnt5b overexpression in combination with stimulation of the beta-catenin dependent or beta-catenin independent Wnt signaling. Expression of Wnt5b was, like Wnt5a, down-regulated upon induction of differentiation and both inhibit beta-catenin dependent Wnt signaling at the initiation of adipogenesis. Wnt5b additionally appears to be a potent enhancer of adipogenic capacity by stimulation of PPARgamma and aP2. Down-regulation of Wnt5b could therefore contribute to decreased adipogenesis observed in T2DM diabetic subjects. PMID: 19577541 [PubMed - indexed for MEDLINE

Wnt/frizzled signalling modulates the migration and differentiation of immortalized cardiac fibroblasts

The Wnt/frizzled (Fzd) signal transduction cascade has been implicated in the proliferation, differentiation, and migration of many cell types, but the role of this pathway in cardiac fibroblast differentiation is not known. Our lab previously showed an up-regulation of Fzd-1 and -2 expression in myofibroblasts after myocardial infarction (MI), indicating a potential role for the Fzd receptor in fibroblast-myofibroblast differentiation. The present study was performed to further define the role of specific Wnt and Fzd proteins in the proliferation, migration, and differentiation of cardiac fibroblasts. Because primary fibroblasts become senescent after a few passages and are difficult to transfect, we immortalized rat cardiac fibroblasts with telomerase [cardiac fibroblasts immortalized with telomerase (CFIT)]. Proliferation of CFIT was not significantly influenced by Wnt/Fzd signalling. The migration, however, was attenuated by all Wnt/Fzd combinations tested. Also, specific Wnt/Fzd combinations modulated the expression of the following myofibroblast markers: collagen I alpha 1, collagen III, fibronectin and its splice variants, and alpha-smooth muscle actin. The results indicate that myofibroblast migration and differentiation, but not proliferation, can be modulated by interventions in Wnt/Fzd signalling. Therefore, Wnt/Fzd signalling may serve as a novel therapeutic target to ameliorate wound healing after MI