Publications by authors named "Andre van Wijnen"

Multipotent bone marrow mesenchymal stromal/stem cells (MSCs) respond to mechanical forces. MSCs perceive static and dynamic forces through focal adhesions, as well as cytoskeletal and intranuclear actin. Dynamic strain stimulates nuclear β-catenin (Ctnnb1) that controls gene expression and suppresses osteogenesis.

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The CRISPR/Cas9 system is a powerful tool for genome editing, utilizing the Cas9 nuclease and programmable single guide RNA (sgRNA). However, the Cas9 nuclease activity can be disabled by mutation, resulting in catalytically deactivated Cas9 (dCas9). By combining the customizable sgRNA with dCas9, researchers can inhibit specific gene expression (CRISPR interference, CRISPRi) or activate the expression of a target gene (CRISPR activation, CRISPRa).

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  • * This review examines how changes in the function of KAT3A and KAT3B are linked to neurodegenerative diseases like Huntington's and Alzheimer's, emphasizing their roles in chromatin regulation and cellular signaling pathways.
  • * The research highlights the importance of the KAT3 proteins in maintaining cellular function and suggests that understanding their regulatory processes could lead to new discoveries in neurodevelopment and treatments for neurodegenerative disorders.
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  • The study explores how the Vision Transformer (ViT) can be used for analyzing medical images, specifically for diagnosing osteoporosis from X-ray images.
  • Researchers compared the performance of ViT to traditional convolutional neural networks (CNNs) to see which method was more effective in classification tasks.
  • Results indicated that ViT outperforms CNNs, especially when there is ample training data available, leading to better solutions for medical image analysis.
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The epithelial to mesenchymal transition (EMT) is a multistep process involving structural and functional alterations that are required for cancer metastasis, as well as loss of epithelial markers (e.g., E-cadherin/CDH1) and gain of mesenchymal markers (e.

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Background & Aims: Restricted gastric motor functions contribute to aging-associated undernutrition, sarcopenia, and frailty. We previously identified a decline in interstitial cells of Cajal (ICC; gastrointestinal pacemaker and neuromodulator cells) and their stem cells (ICC-SC) as a key factor of gastric aging. Altered functionality of the histone methyltransferase enhancer of zeste homolog 2 (EZH2) is central to organismal aging.

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Regenerative dental medicine continuously expands to improve treatments for prevalent clinical problems in dental and oral medicine. Stem cell based translational opportunities include regenerative therapies for tooth restoration, root canal therapy, and inflammatory processes (e.g.

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  • Dupuytren's disease is a fibroproliferative condition that leads to serious hand deformities and currently relies on limited treatments that often only provide partial relief.
  • *The study emphasizes the need for a deeper understanding of the disease's systemic factors, like cytokines and growth factors, to improve treatment options and disease management.
  • *By identifying specific biomarkers linked to Dupuytren's disease, researchers hope to enhance diagnosis, monitor treatment responses, and potentially find new therapies that can also apply to other fibrotic disorders.*
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Many recent studies in evolutionary biology have expanded and refined definitions of biological evolution and natural selection. Current evolutionary models incorporate different adaptive and non-adaptive processes based on molecular genetic changes and how DNA is modified over time in unicellular species, or in germline versus somatic cells in metazoan species. Cogent arguments can be raised for the view that natural selection should be considered a biological law, consistent with quantitative mathematical equations that describe the fitness of individuals, as well as variations within and among populations.

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  • Traumatic conditions during surgery can lead to early immune responses, potentially leading to long-lasting changes in leukocyte (white blood cell) activity and increased health risks.
  • A study involving 13 patients undergoing elective cardiac surgery showed significant differences in gene expression in T cells and monocytes before and after surgery, indicating persistent changes in the immune system.
  • Monocytes displayed specific gene expressions related to protein degradation and inflammation over time, suggesting ongoing issues that could affect recovery and health, emphasizing the need for careful clinical consideration post-surgery.
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  • - Obesity negatively affects mesenchymal stem/stromal cells (MSCs), leading to tissue degeneration and lower healing potential, with unclear underlying mechanisms regarding mitochondrial gene alterations.
  • - A study compared MSCs from obese and non-obese individuals, revealing significant changes in hydroxymethylcytosine (5hmC) profiles and gene expression related to mitochondrial function, impacting processes like cell survival, energy production, and neuron formation.
  • - Findings showed that obese MSCs had structural and functional mitochondrial impairments, which could be partially reversed through epigenetic modulation, highlighting potential pathways for developing therapies to combat obesity-related health issues.
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Stem cell therapies hold promise in addressing the burden of neurodegenerative diseases with human embryonic neural stem cells (hNSC-H9s) and bone marrow-derived human mesenchymal stem cells (hMSCs) as viable candidates. The induction of hMSC neurospheres (hMSC-IN) generate a more lineage-restricted common neural progenitor-like cell population, potentially tunable by heparan sulfate proteoglycans (HSPGs). We examined CpG (5 mC) site methylation patterns using Illumina Infinium 850 K EPIC arrays in hNSC-H9, hMSCs and hMSC-IN cultures with HSPG agonist heparin at early and late phases of growth.

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  • Osteoarthritis (OA) causes pain and damage to the cartilage in joints.
  • Scientists created a special treatment called Nano-PAZII, which is a tiny particle version of an existing cancer drug that helps with OA.
  • In tests with mice, a single injection of Nano-PAZII reduced joint pain and protected cartilage without causing serious side effects.
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  • - Bone development and maintenance are influenced by environmental factors and hormones that activate signaling pathways, affecting gene expression in the nucleus.
  • - Gene expression related to bone is regulated by chromatin structure, which controls the accessibility of DNA sequences necessary for bone formation, especially during early embryonic stages to prevent premature mineralization.
  • - Key epigenetic regulators, including various enzymes, play crucial roles in either promoting or inhibiting bone cell differentiation and function, impacting the behavior of stem cells and their development into bone-forming cells (osteoblasts).
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Objective: This proof-of-concept study investigated an improved cell-based injection therapy combining mesenchymal stem cells (MSCs) and meniscus cells (MCs) to support superior meniscus allograft repopulation and early revival compared to injecting MSCs alone.

Design: In this controlled laboratory study, frozen meniscus allograft samples were injected vertically with a cell suspension containing different ratios of MSCs and MCs or control (lactated ringers) and cultured for 28 days. Samples were analyzed weekly for cell viability, migration, and metabolism using histological and biochemical assays.

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Osteoarthritis (OA) is a multifactorial degenerative joint disease of which the underlying mechanisms are yet to be fully understood. At the molecular level, multiple factors including altered signaling pathways, epigenetics, metabolic imbalance, extracellular matrix degradation, production of matrix metalloproteinases, and inflammatory cytokines, are known to play a detrimental role in OA. However, these factors do not initiate OA, but are mediators or consequences of the disease, while many other factors causing the etiology of OA are still unknown.

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Arthrofibrosis, which causes joint motion restrictions, is a common complication following total knee arthroplasty (TKA). Key features associated with arthrofibrosis include myofibroblast activation, knee stiffness, and excessive scar tissue formation. We previously demonstrated that adiponectin levels are suppressed within the knee tissues of patients affected by arthrofibrosis and showed that AdipoRon, an adiponectin receptor agonist, exhibited anti-fibrotic properties in human mesenchymal stem cells.

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The skeleton forms from multipotent human mesenchymal stem cells (hMSCs) competent to commit to specific lineages. Long noncoding RNAs (lncRNAs) have been identified as key epigenetic regulators of tissue development. However, regulation of osteogenesis by lncRNAs as mediators of commitment to the bone phenotype is largely unexplored.

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Pain is the prime symptom of osteoarthritis (OA) that directly affects the quality of life. Protein kinase Cδ (PKCδ/Prkcd) plays a critical role in OA pathogenesis; however, its significance in OA-related pain is not entirely understood. The present study investigated the functional role of PKCδ in OA pain sensation.

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The serotonin transporter (5-hydroxytryptamine transporter [5-HTT], Serotonin Transporter (SERT), SLC6A4) modulates the activity of serotonin via sodium-dependent reuptake. Given the established importance of serotonin in the control of pain, 5-HTT has received much interest in studies of pain states and as a pharmacological target for serotonin reuptake inhibitors (SRIs). Animal models expressing varying levels of 5-HTT activity show marked differences in pain behaviors and analgesic responses, as well as many serotonin-related physiological effects.

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 Chronic injuries to the scapholunate ligament (SLIL) alter carpal kinematics and may progress to early degenerative osteoarthritis. To date, there is no consensus for the best method for SLIL reconstruction. This study aims to assess the use of growth factors (bone morphogenetic protein [BMP]2 and growth and differentiation factor 5 [GDF5]) for compartmentalized regeneration of bone and ligament in this multiphasic scaffold in a rabbit knee model.

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Osteogenic differentiation of mesenchymal cells is controlled by epigenetic enzymes that regulate post-translational modifications of histones. Compared to acetyl or methyltransferases, the physiological functions of protein arginine methyltransferases (PRMTs) in osteoblast differentiation remain minimally understood. Therefore, we surveyed the expression and function of all nine mammalian PRMT members during osteoblast differentiation.

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Bivalent epigenomic regulatory domains containing both activating histone 3 lysine 4 (H3K4me3) and repressive lysine 27 (H3K27me3) trimethylation are associated with key developmental genes. These bivalent domains repress transcription in the absence of differentiation signals but maintain regulatory genes in a poised state to allow for timely activation. Previous studies demonstrated that enhancer of zeste homolog 2 (Ezh2), a histone 3 lysine 27 (H3K27) methyltransferase, suppresses osteogenic differentiation and that inhibition of Ezh2 enhances commitment of osteoblast progenitors in vitro and bone formation in vivo.

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Osteoblast differentiation is epigenetically suppressed by the H3K27 methyltransferase EZH2, and induced by the morphogen BMP2 and transcription factor RUNX2. These factors also regulate distinct G protein coupled receptors (GPRCs; e.g.

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