Search results for "gate"
showing 10 items of 1811 documents
Albumin-Folate Conjugates for Drug-targeting in Photodynamic Therapy.
2016
Photodynamic therapy (PDT) is based on the cytotoxicity of photosensitizers in the presence of light. Increased selectivity and effectivity of the treatment is expected if a specific uptake of the photosensitizers into the target cells, often tumor cells, can be achieved. An attractive transporter for that purpose is the folic acid receptor α (FRα), which is overexpressed on the surface of many tumor cells and mediates an endocytotic uptake. Here, we describe the synthesis and photobiological characterization of polar β-carboline derivatives as photosensitizers covalently linked to folate-tagged albumin as the carrier system. The particles were taken up by KB (human carcinoma) cells within …
Toxic Tau Oligomers Modulated by Novel Curcumin Derivatives
2019
AbstractThe pathological aggregation and accumulation of tau, a microtubule-associated protein, is a common feature amongst more than 18 different neurodegenerative diseases that are collectively known as tauopathies. Recently, it has been demonstrated that the soluble and hydrophobic tau oligomers are highly toxic in vitro due to their capacity towards seeding tau misfolding, thereby propagating the tau pathology seen across different neurodegenerative diseases. Modulating the aggregation state of tau oligomers through the use of small molecules could be a useful therapeutic strategy to target their toxicity, regardless of other factors involved in their formation. In this study, we screen…
Synthesis and antiproliferative activity of a natural like glycoconjugate polycyclic compound
2016
Abstract A natural like O -glycoconjugate polycyclic compound 4 was obtained by a multistep procedure starting from N -(3-methyl-1-(4-nitrophenyl)-1 H -pyrazol-5-yl)acetamide. The glycosyl derivative 4 showed antiproliferative activity against all the tumoral cell lines of the NCI panel in the range 0.47–5.43 μ M. Cytofluorimetric analysis performed on MDA-MB231, a very aggressive breast cancer cell line, which does not express estrogen, progesterone and HER-2/neu receptors, showed that 4 is able to induce prolonged cell cycle arrest at G2/M phase and morphological signs of differentiation. These events are correlated with down-regulation of both cyclin B1 and cdc2, the cyclins involved in…
Self-adjuvanting C18 lipid vinil sulfone-PP2A vaccine: study of the induced immunomodulation against Trichuris muris infection
2017
Despite the importance of the adjuvant in the immunization process, very few adjuvants merge with the antigens in vaccines. A synthetic self-adjuvant oleic-vinyl sulfone (OVS) linked to the catalytic region of recombinant serine/threonine phosphatase 2A from the nematode Angiostrongylus costaricensis (rPP2A) was used for intranasal immunization in mice previously infected with Trichuris muris . The animal intranasal immunization with rPP2A-OVS showed a reduction of 99.01% in the number of the nematode eggs and 97.90% in adult. The immunohistochemical analysis of the intestinal sections showed that in immunized animals with lipopeptide the mucus was significantly higher than in the other ex…
Dual proteotoxic stress accelerates liver injury via activation of p62‐Nrf2
2021
Protein accumulation is the hallmark of various neuronal, muscular, and other human disorders. It is also often seen in the liver as a major protein-secretory organ. For example, aggregation of mutated alpha1-antitrypsin (AAT), referred to as PiZ, is a characteristic feature of AAT deficiency, whereas retention of hepatitis B surface protein (HBs) is found in chronic hepatitis B (CHB) infection. We investigated the interaction of both proteotoxic stresses in humans and mice. Animals overexpressing both PiZ and HBs (HBs-PiZ mice) had greater liver injury, steatosis, and fibrosis. Later they exhibited higher hepatocellular carcinoma load and a more aggressive tumor subtype. Although PiZ and H…
Design, synthesis and preliminary evaluation of dopamine-amino acid conjugates as potential D1 dopaminergic modulators.
2016
Abstract The dopamine-amino acid conjugate DA-Phen was firstly designed to obtain a useful prodrug for the therapy of Parkinson's disease, but experimental evidence shows that it effectively interacts with D1 dopamine receptors (D1DRs), leading to an enhancement in cognitive flexibility and to the development of adaptive strategies in aversive mazes, together with a decrease in despair-like behavior. In this paper, homology modelling, molecular dynamics, and site mapping of D1 receptor were carried out with the aim of further performing docking studies on other dopamine conjugates compared with D1 agonists, in the attempt to identify new compounds with potential dopaminergic activity. Two n…
First international descriptive and interventional survey for cholesterol and non-cholesterol sterol determination by gas- and liquid-chromatography–…
2019
International audience; Serum concentrations of lathosterol, the plant sterols campesterol and sitosterol and the cholesterol metabolite 5alpha-cholestanol are widely used as surrogate markers of cholesterol synthesis and absorption, respectively. Increasing numbers of laboratories utilize a broad spectrum of well-established and recently developed methods for the determination of cholesterol and non-cholesterol sterols (NCS). In order to evaluate the quality of these measurements and to identify possible sources of analytical errors our group initiated the first international survey for cholesterol and NCS. The cholesterol and NCS survey was structured as a two-part survey which took place…
Transient Multivalent Nanobody Targeting to CD206-Expressing Cells via PH-Degradable Nanogels
2020
To target nanomedicines to specific cells, especially of the immune system, nanobodies can be considered as an attractive tool, as they lack the Fc part as compared to traditional antibodies and, thus, prevent unfavorable Fc-receptor mediated mistargeting. For that purpose, we have site-specifically conjugated CD206/MMR-targeting nanobodies to three types of dye-labeled nanogel derivatives: non-degradable nanogels, acid-degradable nanogels (with ketal crosslinks), and single polymer chains (also obtained after nanogel degradation). All of them can be obtained from the same reactive ester precursor block copolymer. After incubation with naï
Stability of Alkyl Chain-Mediated Lipid Anchoring in Liposomal Membranes
2020
Lipid exchange among biological membranes, lipoprotein particles, micelles, and liposomes is an important yet underrated phenomenon with repercussions throughout the life sciences. The premature loss of lipid molecules from liposomal formulations severely impacts therapeutic applications of the latter and thus limits the type of lipids and lipid conjugates available for fine-tuning liposomal properties. While cholesterol derivatives, with their irregular lipophilic surface shape, are known to readily undergo lipid exchange and interconvert, e.g., with serum, the situation is unclear for lipids with regular, linear-shaped alkyl chains. This study compares the propensity of fluorescence-label…
Linear biocompatible glyco-polyamidoamines as dual action mode virus infection inhibitors with potential as broad-spectrum microbicides for sexually …
2016
AbstractThe initial steps of viral infections are mediated by interactions between viral proteins and cellular receptors. Blocking the latter with high-affinity ligands may inhibit infection. DC-SIGN, a C-type lectin receptor expressed by immature dendritic cells and macrophages, mediates human immunodeficiency virus (HIV) infection by recognizing mannose clusters on the HIV-1 gp120 envelope glycoprotein. Mannosylated glycodendrimers act as HIV entry inhibitors thanks to their ability to block this receptor. Previously, an amphoteric, but prevailingly cationic polyamidoamine named AGMA1 proved effective as infection inhibitor for several heparan sulfate proteoglycan-dependent viruses, such …