Barrier function regulation, angiogenic potential, and immune response modulation are only a few of the many roles of the vascular system that nowadays represent one of the main targets for environmental pollutants, in particular, pesticides. We have used human umbilical vein endothelial cells (HUVECs) as an in vitro model to investigate the effects of pesticides on the activation of the NALP3-CASP1-IL-1β inflammatory pathway using real time PCR (RT-PCR) and immunofluorescence investigations, reactive oxygen species (ROS) generation, and morphological alterations with scanning electron microscopy (SEM) analysis. Our findings offer a comprehensive evaluation of the cellular and molecular damage induced by pesticide exposure and show strong inflammasome activation.
View Article and Find Full Text PDFLymphatic vessels are essential for preventing the accumulation of harmful components within peripheral tissues, including the artery wall. Various endogenous mechanisms maintain adequate lymphatic function throughout life, with platelets being essential for preserving lymphatic vessel integrity. However, since lymph lacks platelets, their impact on the lymphatic system has long been viewed as restricted to areas where lymphatics intersect with blood vessels.
View Article and Find Full Text PDFIntroduction: Glass coverslips are used as a substrate since Harrison's initial nerve cell culture experiments in 1910. In 1974, the first study of brain cells seeded onto polylysine (PL) coated substrate was published. Usually, neurons adhere quickly to PL coating.
View Article and Find Full Text PDFGraphene oxide (GO), derived from graphene, has remarkable chemical-physical properties such as stability, strength, and thermal or electric conductivity and additionally shows antibacterial and anti-inflammatory properties. The present study aimed to evaluate the anti-inflammatory effects of polypropylene suture threads buttons (PPSTBs), enriched with two different concentrations of GO, in the modulation of the inflammatory pathway TLR4/MyD 88/NFκB p65/NLRP3 induced by the () lipopolysaccharide (LPS-E). The gene and the protein expression of inflammatory markers were evaluated in an in vitro model of primary human gingival fibroblasts (hGFs) by real-time PCR, western blotting, and immunofluorescence analysis.
View Article and Find Full Text PDFTitanium (Ti) nanotopography modulates the osteogenic response to exogenous bone morphogenetic protein 7 (BMP-7) in vitro, supporting enhanced alkaline phosphatase mRNA expression and activity, as well as higher osteopontin (OPN) mRNA and protein levels. As the biological effects of OPN protein are modulated by its proteolytic cleavage by serum proteases, this in vitro study evaluated the effects on osteogenic cells in the presence of a physiological blood clot previously formed on a BMP-7-coated nanostructured Ti surface obtained by chemical etching (Nano-Ti). Pre-osteoblastic MC3T3-E1 cells were cultured during 5 days on recombinant mouse (rm) BMP-7-coated Nano-Ti after it was implanted in adult female C57BI/6 mouse dorsal dermal tissue for 18 h.
View Article and Find Full Text PDFThis study evaluates the effects of the availability of exogenous BMP-7 on osteoblastic cells' differentiation on a nanotextured Ti surface obtained by chemical etching (Nano-Ti). The MC3T3-E1 and UMR-106 osteoblastic cell lines were cultured for 5 and 7 days, respectively, on a Nano-Ti surface and on a control surface (Control-Ti) in an osteogenic medium supplemented with either 40 or 200 ng/mL recombinant mouse (rm) BMP-7. The results showed that MC3T3-E1 cells exhibited distinct responsiveness when exposed to each of the two rmBMP-7 concentrations, irrespective of the surface.
View Article and Find Full Text PDFCells sense and respond to mechanical cues from the surrounding substrate through filopodia. Regulation of cellular biomechanics operates at the nanoscale. Therefore, a better understanding of the relationship between filopodia and nanoscale surface features is highly relevant for the rational design of implant surfaces.
View Article and Find Full Text PDFIn a systemic effort to survive environmental stress, organ systems fluctuate and adapt to overcome external pressures. The evolutionary drive back toward homeostasis makes it difficult to determine if an organism experienced a toxic exposure to stress, especially in early prenatal and neonatal periods of development. Previous studies indicate that primary human teeth may provide historical records of experiences related to stressors during that early time window.
View Article and Find Full Text PDFThe mouth environment comprises the second most significant microbiome in the body, and its equilibrium is critical in oral health. Secretory calcium-binding phosphoprotein proline-glutamine rich 1 (SCPPPQ1), a protein normally produced by the gingival epithelium to mediate its attachment to teeth, was suggested to be bactericidal. Our aim was to further explore the antibacterial potential of human SCPPPQ1 by characterizing its mode of action and identifying its active portions.
View Article and Find Full Text PDFMetabolic rewiring and redox balance play pivotal roles in cancer. Cellular senescence is a barrier for tumorigenesis circumvented in cancer cells by poorly understood mechanisms. We report a multi-enzymatic complex that reprograms NAD metabolism by transferring reducing equivalents from NADH to NADP.
View Article and Find Full Text PDFGlandular tumors of jaw bones present, most often, histopathologic features of salivary gland and, rarely, of cutaneous glandular neoplasms. They are thought to originate from odontogenic epithelium. An unusual maxillary tumor presenting as a radiolucency in the periapical area of the right permanent lateral incisor of a 74-year-old male is presented causing root resorption.
View Article and Find Full Text PDFChemical neurotransmission typically occurs through synapses. Previous ultrastructural examinations of monoamine neuron axon terminals often failed to identify a pre- and postsynaptic coupling, leading to the concept of "volume" transmission. Whether this results from intrinsic properties of these neurons remains undefined.
View Article and Find Full Text PDFThe gingival seal around teeth prevents bacteria from destroying the tooth-supporting tissues and disseminating throughout the body. Porphyromonas gingivalis, a major periodontopathogen, degrades components of the specialized extracellular matrix that mediates attachment of the gingiva to the tooth. Of these, secretory calcium-binding phosphoprotein proline-glutamine rich 1 (SCPPPQ1) protein has a distinctive resistance to degradation, suggesting that it may offer resistance to bacterial attack.
View Article and Find Full Text PDFAppl Environ Microbiol
March 2021
Endospore formation is used by members of the phylum Firmicutes to withstand extreme environmental conditions. Several recent studies have proposed endospore formation in species outside of Firmicutes, particularly in and , members of the phylum Proteobacteria. Here, we aimed to investigate endospore formation in these two species by using advanced imaging and analytical approaches.
View Article and Find Full Text PDFNanomaterials (Basel)
November 2020
Nanoscale surface modifications influence peri-implant cell fate decisions and implant loading generates local tissue deformation, both of which will invariably impact bone healing. The objective of this study is to determine how loading affects healing around implants with nanotopography. Implants with a nanoporous surface were placed in over-sized osteotomies in rat tibiae and held stable by a system that permits controlled loading.
View Article and Find Full Text PDFHere, we experimentally expand understanding of the reactions and enzymes involved in ATCC 19377 S and metabolism by developing models that integrate gene expression analyzed by RNA-Seq, solution sulfur speciation, electron microscopy and spectroscopy. The metabolism model involves the conversion of to , S and mediated by the sulfur oxidase complex (Sox), tetrathionate hydrolase (TetH), sulfide quinone reductase (Sqr), and heterodisulfate reductase (Hdr) proteins. These same proteins, with the addition of rhodanese (Rhd), were identified to convert S to , and polythionates in the S metabolism model.
View Article and Find Full Text PDFACS Appl Mater Interfaces
April 2020
We have evaluated the response to nanotopography of CHO-K1 cells that express wild-type paxillin or paxillin with mutations at serine 273 that inhibit phosphorylation. Cells were grown on nanoporous and polished titanium surfaces. With all cell types, immunofluorescence showed that adhesion and spreading were minimally affected on the treated surface and that the actin filaments were more abundant and well-aligned.
View Article and Find Full Text PDFJ Biomed Mater Res B Appl Biomater
April 2020
Experimental studies on the effect of micromotion on bone healing around implants are frequently conducted in long bones. In order to more closely reflect the anatomical and clinical environments around dental implants, and eventually be able to experimentally address load-management issues, we have developed a system that allows initial stabilization, protection from external forces, and controlled axial loading of implants. Screw-shaped implants were placed on the edentulous ridge in rat maxillae.
View Article and Find Full Text PDFCalcium phosphate minerals deposit on the elastin-rich medial layers of arteries in the majority of seniors, diabetic, and chronic kidney disease patients, causing severe cardiovascular complications. There is no cure for medial calcification, and the mechanism of mineral formation on elastin layers is unknown. Here we propose cross-linked elastin-like polypeptide membranes as models to study medial calcification.
View Article and Find Full Text PDFThe junctional epithelium (JE) is a specialized portion of the gingiva that seals off the tooth-supporting tissues from the oral environment. This relationship is achieved via a unique adhesive extracellular matrix that is, in fact, a specialized basal lamina (sBL). Three unique proteins - amelotin (AMTN), odontogenic ameloblast-associated (ODAM), and secretory calcium-binding phosphoprotein proline-glutamine rich 1 (SCPPPQ1) - together with laminin-332 structure the supramolecular organization of this sBL and determine its adhesive capacity.
View Article and Find Full Text PDFInt J Nanomedicine
February 2019
Background: Nanoscale surface modifications are widely touted to improve the biocompatibility of medically relevant materials. Immune cells, such as macrophages, play a critical role in the initial healing events following implantation.
Methods: To understand the response of macrophages to nanotopography better, we exposed U937-derived macrophages to a distinctive mesoporous titanium surface (TiNano) produced by a process of simple chemical nanocavitation, and to mechanically polished titanium (TiPolished) and glass coverslip (Glass) surfaces as controls.
Background: Dicer is a 219-kDa protein that plays key roles in gene regulation, particularly as the ribonuclease III enzyme responsible for cleaving precursor miRNA substrates. Its enzymatic activity is highly regulated by protein factors, and this regulation can impact on the levels of miRNAs and modulate the behavior of a cell. To better understand the underlying mechanisms of regulation, detailed enzymatic and structural characterization of Dicer are needed.
View Article and Find Full Text PDFDue to the technical challenges of large-scale microscopy and analysis, to date only limited knowledge has been made available about axon morphometry (diameter, shape, myelin thickness, volume fraction), thereby limiting our understanding of neuronal microstructure and slowing down research on neurodegenerative pathologies. This study addresses this knowledge gap by establishing a state-of-the-art acquisition and analysis framework for mapping axon morphometry, and providing the first comprehensive mapping of axon morphometry in the human spinal cord. We dissected, fixed and stained a human spinal cord with osmium tetroxide, and used a scanning electron microscope to image the entirety of 23 axial slices, covering C1 to L5 spinal levels.
View Article and Find Full Text PDFMany bacterial pathogens employ multicomponent protein complexes such as type IV secretion systems (T4SSs) to transfer virulence factors into host cells. Here we studied the interaction between two essential T4SS components: the very hydrophobic inner membrane protein VirB6, which may be a component of the translocation channel, and VirB10, which links the inner and outer bacterial membranes. To map the interaction site between these two T4SS components, we conducted alanine scanning and deleted six-amino acid stretches from the N-terminal periplasmic domain of VirB6 from Using the bacterial two-hybrid system to analyze the effects of these alterations on the VirB6-VirB10 interaction, we identified the amino acid regions 16-21 and 28-33 and Leu-18 in VirB6 as being required for this interaction.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
September 2018
When bone implants are loaded, they are inevitably subjected to displacement relative to bone. Such micromotion generates stress/strain states at the interface that can cause beneficial or detrimental sequels. The objective of this study is to better understand the mechanobiology of bone healing at the tissue-implant interface during repeated loading.
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