Intervertebral disc (IVD) degeneration is characterized by significant biochemical and histomorphological alterations, such as loss of extracellular matrix (ECM) integrity, by abnormal synthesis of ECM main components, resultant from altered anabolic/catabolic cell activities and cell death. Mesenchymal Stem/Stromal Cell (MSC) migration towards degenerated IVD may represent a viable strategy to promote tissue repair/regeneration. Here, human MSCs (hMSCs) were seeded on top of cartilaginous endplates (CEP) of nucleotomized IVDs of bovine origin and cultured ex vivo up to 3 weeks. hMSCs migrated from CEP towards the lesion area and significantly increased expression of collagen type II and aggrecan in IVD, namely in the nucleus pulposus. Concomitantly, hMSCs stimulated the production of growth factors, promoters of ECM synthesis, such as fibroblast growth factor 6 (FGF-6) and 7 (FGF-7), platelet-derived growth factor receptor (PDGF-R), granulocyte-macrophage colony-stimulating factor (GM-CSF) and insulin-like growth factor 1 receptor (IGF-1sR). Overall, our results demonstrate that CEP can be an alternative route to MSC-based therapies for IVD regeneration through ECM remodeling, thus opening new perspectives on endogenous repair capacity through MSC recruitment.

An analytical method based on solid-phase extraction followed by gas chromatography mass spectrometry (GC-MS) was developed and validated for the quantification of 39 pesticides with distinct physico-chemical characteristics (including some degradates), in estuarine water samples. The method includes pre-concentration of samples (2500-fold factor), in OASIS HLB cartridges, by solid phase extraction. The analysed pesticides included organochlorines, organophosphorous, triazines, pyrethroids and other miscellaneous compounds, that are usually analysed separately. Method detection limits were between 3.6 and 61.2 ng L⁻¹. The obtained sensitivity and accuracy, associated with the inherent confirmatory potential of GC-MS, validate the method as a toll in environmental monitoring. Analyses of water samples (n = 84) taken from the Douro River estuary, from March to May 2009, showed the presence of all assayed pesticides, among which 71.6% where above the limits of quantification. Besides, the feasibility of the method for chemical monitoring was highlighted by establishing a first pattern of spatial-temporal fluctuation for all classes of pesticides in the estuary, showing a significant increase of their concentrations in April and mainly at the margin bordering the city of Porto. Moreover, the finding of environmental hazardous amounts of hexachlorbenzene, endrin, endosulfan (all forms), DDTs, chlorfenvinfos Z and simazine pose a clear risk for local aquatic wildlife, and eventually to humans, by direct exposure or by consumption of contaminated fish.

This study focusses on the development of a magnetic zeolite nanocomposite as a suitable platform towards the design of a theranostic system. Herein, we explored its ability to act as a T₂-MRI contrast enhancer when magnetic nanoparticles are incorporated in its structure.

Spinocerebellar ataxia type 3 (SCA3) is caused by the expansion of a glutamine repeat in the protein ataxin-3, which is deposited as intracellular aggregates in affected brain regions. Despite the controversial role of ataxin-3 amyloid structures in SCA3 pathology, the identification of molecules with the capacity to prevent aberrant self-assembly and stabilize functional conformation(s) of ataxin-3 is a key to the development of therapeutic solutions. Amyloid-specific kinetic assays are routinely used to measure rates of protein self-assembly in vitro and are employed during screening for fibrillation inhibitors. The high tendency of ataxin-3 to assemble into oligomeric structures implies that minor changes in experimental conditions can modify ataxin-3 amyloid assembly kinetics. Here, we determine the self-association rates of ataxin-3 and present a detailed study of the aggregation of normal and pathogenic ataxin-3, highlighting the experimental conditions that should be considered when implementing and validating ataxin-3 amyloid progress curves in different settings and in the presence of ataxin-3 interactors. This assay provides a unique and robust platform to screen for modulators of the first steps of ataxin-3 aggregation—a starting point for further studies with cell and animal models of SCA3.