Proteoglycans are secreted into the extracellular matrix of virtually all cell types and function in several cellular processes. They consist of a core protein onto which glycosaminoglycans (e.g., heparan or chondroitin sulphates), are attached. Proteoglycans are important modulators of gradient formation and signal transduction. Impaired biosynthesis of heparan sulphate glycosaminoglycans causes osteochondroma, the most common bone tumour to occur during adolescence. Cytochemical staining with positively charged dyes (e.g., polyethyleneimine-PEI) allows, visualisation of proteoglycans and provides a detailed description of how proteoglycans are distributed throughout the cartilage matrix. PEI staining was studied by electron and reflection contrast microscopy in human growth plates, osteochondromas and five different proteoglycan-deficient zebrafish mutants displaying one of the following skeletal phenotypes: dackel (dak/ext2), lacking heparan sulphate and identified as a model for human multiple osteochondromas; hi307 (β3gat3), deficient for most glycosaminoglycans; pinscher (pic/slc35b2), presenting with defective sulphation of glycosaminoglycans; hi954 (uxs1), lacking most glycosaminoglycans; and knypek (kny/gpc4), missing the protein core of the glypican-4 proteoglycan. The panel of genetically well-characterized proteoglycan-deficient zebrafish mutants serves as a convincing and comprehensive study model to investigate proteoglycan distribution and the relation of this distribution to the model mutation status. They also provide insight into the distributions and gradients that can be expected in the human homologue. Human growth plate, wild-type zebrafish and fish mutants with mild proteoglycan defects (hi307 and kny) displayed proteoglycans distributed in a gradient throughout the matrix. Although the mutants pic and hi954, which had severely impaired proteoglycan biosynthesis, showed no PEI staining, dak mutants demonstrated reduced PEI staining and no gradient formation. Most chondrocytes from human osteochondromas showed normal PEI staining. However, approximately 10% of tumour chondrocytes were similar to those found in the dak mutant (e.g., lack of PEI gradients). The cells in the reduced PEI-stained areas are likely associated with loss-of-function mutations in the EXT genes, and they might contribute to tumour initiation by disrupting the gradients.
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http://dx.doi.org/10.1002/path.2886 | DOI Listing |
Polymers (Basel)
December 2024
CIRENYS, Escuela de Química y Farmacia, Facultad de Ciencias Médicas, Universidad Bernardo O'Higgins, General Gana 1702, Santiago 8370854, Chile.
Biofouling in membrane filtration systems poses significant operational challenges, leading to decreased permeate flux. The aim of this work was to study the anti-biofilm properties of new nanofiltration membranes produced via layer-by-layer, LBL, assembly by coating a polyvinylidene fluoride (PVDF) support with a polyethylenimine (PEI) and poly(acrylic acid)/graphene oxide (PAA-GO) mixture. The membranes were characterized according to contact angle, scanning electron microscopy (SEM), atomic force microscopy and their Z-potential.
View Article and Find Full Text PDFMolecules
December 2024
School of Water and Environment, Chang'an University, Xi'an 710054, China.
Platanus officinalis fibers (PFs) taking advantage of high-availability, eco-friendly and low-cost characteristics have attracted significant focus in the field of biomaterial application. Polyethyleneimine grafted with polydopamine on magnetic Platanus officinalis fibers (PEI-PDA@M-PFs) were prepared through a two-step process of mussel inspiration and the Michael addition reaction, which can work as an effective multifunctional biomass adsorbent for anionic dye with outstanding separation capacity and efficiency. The as-prepared PEI-PDA@M-PFs possess desirable hydrophilicity, magnetism and positive charge, along with abundant amino functional groups on the surface, facilitating efficient adsorption and the removal of Eriochrome Black T (EBT) dyes from water.
View Article and Find Full Text PDFJ Immunother Cancer
December 2024
Department of Radiology, and National Clinical Research Center for Geriatric Disorders, Xiangya Hospital Central South University, Changsha, Hunan, China
Background: Tertiary lymphoid structures (TLS) within the tumor microenvironment have been associated with cancer prognosis and therapeutic response. However, the immunological pattern of a high peritumoral TLS (pTLS) density and its clinical potential in hepatocellular carcinoma (HCC) remain poor. This study aimed to elucidate biological differences related to pTLS density and develop a radiomic classifier for predicting pTLS density in HCC, offering new insights for clinical diagnosis and treatment.
View Article and Find Full Text PDFJ Biomed Mater Res A
January 2025
Department of Image Center, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, China.
Triggered by the vulnerability to atherosclerotic plaques, cardiovascular diseases (CVDs) have become a main reason for high mortality worldwide. Thus, there is an urgent need to develop functional molecular imaging modalities to improve the detection rate of vulnerable plaques. In this study, polyethyleneimine (PEI) was coated on the surface of mesoporous silica nanoprobes (MSN) loaded with GdO (MSN@GdO), followed by coupling the fluorescent dye carboxylated heptamethine cyanine (IR808), and then the dextran sulfate (DS) was modified on the surface of MSN@GdO@IR808 by electrostatic adsorption, to construct a targeted and pH-responsive magnetic resonance (MR)/near-infrared fluorescence imaging (NIRF) dual-modal nanoprobe (MSN@GdO@IR808@DS nanoparticles).
View Article and Find Full Text PDFArterioscler Thromb Vasc Biol
December 2024
Department of Biochemistry and Molecular Biology, School of Basic Medicine, Hebei Medical University, Shijiazhuang, China. (Q.F., L.G., C.Y., X.L., Y.L., C.L., W.Z., Y.Z., W.Y., Y.M., R.W., L.L., Y.P., H.W., M.H., L.N.).
Background: Unwanted angiogenesis is involved in the progression of various malignant tumors and cardiovascular diseases, and the factors that regulate angiogenesis are potential therapeutic targets. We tested the hypothesis that DCBLD1 (discoidin, CUB, and LCCL domain-containing protein 1) is a coreceptor of VEGFR-2 (vascular endothelial growth factor receptor-2) and modulates angiogenesis in endothelial cells.
Methods: A carotid artery ligation model and retinal angiogenesis assay were used to study angiogenesis using globe knockout or endothelial cell-specific conditional knockout mice in vivo.
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