The Impact of NO on Epithelial Barrier Integrity of a Primary Cell-Based Air-Liquid Interface Model of the Nasal Respiratory Epithelium.

Nitrogen dioxide (NO) is a pervasive gaseous air pollutant with well-documented hazardous effects on health, necessitating precise toxicological characterization. While prior research has primarily focused on lower airway structures, the upper airways, serving as the first line of defense against airborne substances, remain understudied. This study aimed to investigate the functional effects of NO exposure alone or in combination with hypoxia as a secondary stimulus on nasal epithelium and elucidate its molecular mechanisms because hypoxia is considered a pathophysiological factor in the onset and persistence of chronic rhinosinusitis, a disease of the upper airways.

Ag- but Not ZnO-Nanoparticles Disturb the Airway Epithelial Barrier at Subtoxic Concentrations.

Inhalation is considered to be the most relevant source of human exposure to nanoparticles (NPs); however, only a few investigations have addressed the influence of exposing the respiratory mucosal barrier to subcytotoxic doses. In the nasal respiratory epithelium, cells of the mucosa represent one of the first contact points of the human organism with airborne NPs. Disruption of the epithelial barrier by harmful materials can lead to inflammation in addition to potential intrinsic toxicity of the particles.

Influence of Wound Fluid on the Transdifferentiation of Human Mesenchymal Bone Marrow Stem Cells into Cancer-Associated Fibroblasts.

Cancer-associated fibroblasts (CAF) in the tumor microenvironment have a decisive influence on tumor growth and metastatic behavior. The cellular origins as well as the stimuli leading to CAF formation are heterogenous, impeding a precise characterization. Aim of this study was to analyze the influence of cytokines secreted in the process of wound healing, tumor cell-associated paracrine-secreted factors, and direct cell-cell contact on the expression of the CAF-associated markers fibroblast activation protein (FAP), α-smooth muscle actin (α-SMA), thrombospondin-1 (THBS1), and tenascin-c (TNC) by RT-PCR in mesenchymal stem cells (MSC).

Cultivation of Head and Neck Squamous Cell Carcinoma Cells with Wound Fluid Leads to Cisplatin Resistance via Epithelial-Mesenchymal Transition Induction.

Locoregional recurrence is a major reason for therapy failure after surgical resection of head and neck squamous cell carcinoma (HNSCC). The physiological process of postoperative wound healing could potentially support the proliferation of remaining tumor cells. The aim of this study was to evaluate the influence of wound fluid (WF) on the cell cycle distribution and a potential induction of epithelial-mesenchymal transition (EMT).

Investigation of the Immune Modulatory Potential of Zinc Oxide Nanoparticles in Human Lymphocytes.

Zinc oxide nanoparticles (ZnO-NP) are commonly used for a variety of applications in everyday life. In addition, due to its versatility, nanotechnology supports promising approaches in the medical sector. NP can act as drug-carriers in the context of targeted chemo- or immunotherapy, and might also exhibit autonomous immune-modulatory characteristics.

The Radiosensitizing Effect of Zinc Oxide Nanoparticles in Sub-Cytotoxic Dosing Is Associated with Oxidative Stress In Vitro.

Radioresistance is an important cause of head and neck cancer therapy failure. Zinc oxide nanoparticles (ZnO-NP) mediate tumor-selective toxic effects. The aim of this study was to evaluate the potential for radiosensitization of ZnO-NP.

Toxicological characterization of ZnO nanoparticles in malignant and non-malignant cells.

The increasing usage of zinc oxide nanoparticles (ZnO-NPs) in industrial applications as well as in consumer products raises concern regarding their potential adverse effects to a greater extend. Numerous studies have demonstrated toxic properties of NPs, however there is still a lack of knowledge concerning the underlying mechanisms. This study was designed to systematically investigate cytotoxicity, apoptosis, cell cycle alterations, and genotoxicity induced by ZnO-NP.