Genotoxic effects of zinc oxide nanoparticles in nasal mucosa cells are antagonized by titanium dioxide nanoparticles.

Titanium dioxide nanoparticles (TiO-NPs) and zinc oxide nanoparticles (ZnO-NPs) are often used in sunscreens and other consumer products due to their photoprotective properties. However, concern exists regarding them possibly causing cyto- and genotoxic effects. The aim of this study was to assess cyto- and genotoxicity of these nanomaterials after single or combined exposure.

The differentiation of hMSCs counteracts their migration capability and pro-angiogenic effects in vitro.

Human mesenchymal stem cells (hMSCs) have been applied therapeutically in numerous clinical trials. The pro-angiogenic effects of hMSCs, as well as their strong tumor tropism, have been shown both in vitro and in vivo. Some studies suggest using hMSCs as potential drug-carriers for tumor therapy.

Effects of salinomycin and CGP37157 on head and neck squamous cell carcinoma cell lines in vitro.

Surgery, radiation, chemotherapy or a combinations of these are all accepted modalities for the treatment of head and neck squamous cell carcinoma (HNSCC). Despite this, 40‑60% of patients suffering from HNSCC develop loco‑regional failure and/or distant metastases. Salinomycin has been demonstrated to be >100‑fold more effective than paclitaxel at causing cancer stem cell death, therefore, it may offer an important improvement in cancer therapy.

Nicotine derived genotoxic effects in human primary parotid gland cells as assessed in vitro by comet assay, cytokinesis-block micronucleus test and chromosome aberrations test.

Genotoxic effects of nicotine were described in different human cells including salivary gland cells. Based on the high nicotine concentration in saliva of smokers or patients using therapeutic nicotine patches, the current study was performed to evaluate the genotoxic potential of nicotine in human salivary gland cells. Therefore, primary salivary gland cells from 10 patients undergoing parotid gland surgery were exposed to nicotine concentrations between 1 μM and 1000 μM for 1 h in the absence of exogenous metabolic activation.

A hydrogel coating for cochlear implant arrays with encapsulated adipose-derived stem cells allows brain-derived neurotrophic factor delivery.

Conclusion: Human adipose-derived stem cells (ASCs), encapsulated in a fibrin-collagen hydrogel for the coating of an electrode array, produce sufficient amounts of neurotrophic factors and may be suitable for enhancing the bioelectric interface of cochlear implants (CIs).

Objectives: To evaluate different hydrogel compositions loaded with ASCs with regard to delivery of neuroactive substances and mechanical suitability for the coating of a CI electrode array.

Methods: ASCs were cultivated in hydrogels consisting of collagen and fibrin in varying fractions (0:1, 1:1, 1:2, and 1:0).

Human mesenchymal stem cells promote cancer motility and cytokine secretion in vitro.

Interactions of human mesenchymal stem cells (hMSC) with tumors are controversially discussed since there is evidence for both tumor progression as well as tumor inhibition by hMSC. The objective of the present study is to investigate whether hMSC support cell motility and cytokine secretion in a head and neck squamous cell carcinoma cell line (HLaC 78). A spheroid model was generated in which the ultrastructure of spheroids was analyzed using scanning electron microscopy (SEM).

Nanoparticle-induced photocatalytic head and neck squamous cell carcinoma cell death is associated with autophagy.

Aim: To characterize molecular mechanisms underlying photocatalytic cell death of head and neck squamous cell carcinoma (HNSCC) by zinc oxide nanoparticles (ZnO-NPs).

Materials & Methods: Human HNSCC-derived FaDu cells were incubated with ZnO-NPs followed by UVA-1 irradiation. Cytotoxicity was assessed by MTT assay and annexin-V propidium iodide test.

Nitrogen dioxide is genotoxic in urban concentrations.

In the discussion on toxic and genotoxic thresholds of air pollutants such as nitrogen dioxide (NO2), realistically low urban concentration ranges are of major interest. For NO2, the WHO defines the annual limit value as corresponding to 0.02 ppm.

Chromosomal aberrations and deoxyribonucleic acid single-strand breaks in adipose-derived stem cells during long-term expansion in vitro.

Background Aims: Adipose-derived stem cells (ASCs) are a promising mesenchymal cell source for tissue engineering approaches. To obtain an adequate cell amount, in vitro expansion of the cells may be required in some cases. To monitor potential contraindications for therapeutic applications in humans, DNA strand breaks and chromosomal aberrations in ASCs during in vitro expansion were examined.

Functional responses of human adipose tissue-derived mesenchymal stem cells to metal oxide nanoparticles in vitro.

Nanoparticles (NPs) are frequently applied in biomedical applications. The use of human mesenchymal stem cells (hMSC) in biomedicine is pivotal, especially in oncology and tissue engineering. Titanium dioxide (TiO2) and zinc oxide (ZnO) NPs are interesting agents in experimental oncology and stem cells are discussed to be a potential vehicle for NPs to tumor sites.

DiI labeling of human adipose-derived stem cells: evaluation of DNA damage, toxicity and functional impairment.

Introduction: Adipose tissue-derived stem cells (ASCs) have become the primary focus of tissue engineering research. To understand their functions and behavior in in vitro and in vivo models, it is mandatory to track the implanted cells and distinguish them from the resident or host cells. A common labeling method is the use of fluorescent dyes, e.

Dynamic changes of the neurogenic potential in the rat cochlear nucleus during post-natal development.

Neuronal stem cells have been described in the post-natal cochlear nucleus recently. The aim of the study was to analyse the neurogenic potential in the cochlear nucleus from the early post-natal days until adulthood. Cochlear nuclei from Sprague-Dawley rats from post-natal day P3 up to P40 were examined.

Effects of salinomycin on human bone marrow-derived mesenchymal stem cells in vitro.

Various hypotheses on the origin of cancer stem cells (CSCs) exist, including that CSCs develop from transformed human bone marrow mesenchymal stem cells (hBMSC). Since the polyether antibiotic salinomycin selectively kills CSCs, the present study aims to elucidate the effects of salinomycin on normal hBMSC. The immunophenotype of hBMSC after salinomycin exposure was observed by flow cytometry.

Antitumor activity of photo-stimulated zinc oxide nanoparticles combined with paclitaxel or cisplatin in HNSCC cell lines.

Zinc oxide nanoparticles (ZnO-NPs) exhibit photocatalytic properties and are used in sunscreen cosmetics and for the degradation of environmental pollutants. Furthermore, ZnO-NPs have proven to induce tumor-selective cell death in human squamous cell carcinoma (HNSCC) in vitro. The aim of the current study was to evaluate cytotoxic effects of UVA-1-activated ZnO-NPs in combination with paclitaxel and cisplatin in HNSCC.

Intraoperative monitoring using cochlear microphonics in cochlear implant patients with residual hearing.

Objectives: To describe a technique for the intraoperative monitoring of residual hearing during a cochlear implant (CI) procedure and, thus, to identify the time of occurrence and surgical steps leading to hearing loss.

Study Design: Prospective audiologic analysis in a patient series.

Setting: Tertiary referral center.

Ex vivo toxicity of nitrogen dioxide in human nasal epithelium at the WHO defined 1-h limit value.

Current pollution limits indicating potential harm to human health caused by nitrogen dioxide have prompted a variety of studies on the cytotoxicity and genotoxicity of nitrogen dioxide (NO₂) in vitro. The present study focuses on toxic effects of NO₂ at the WHO defined 1-h limit value of 200 μg NO₂/m(3) air, equivalent to 0.1 ppm NO₂.

Repetitive exposure to zinc oxide nanoparticles induces dna damage in human nasal mucosa mini organ cultures.

Data on the toxicological properties of zinc oxide nanoparticles (ZnO-NPs) is incomplete. ZnO-NPs may enter humans via inhalation or ingestion. The aim of the current study was to evaluate ZnO-NP-induced genotoxicity in three-dimensional (3D) mini organ cultures (MOCs) of human nasal mucosa following repeated exposure to ZnO-NP and regeneration.

The effect of wound fluid on adipose-derived stem cells in vitro: a study in human cell materials.

After surgery, wound healing begins with a well-orchestrated integration of several cytokines, cells, and extracellular matrix. Some studies show an involvement of stem cells in wound healing. However, little is known about the mechanism that leads to the migration of stem cells.

Growth behavior of cochlear nucleus neuronal cells on semiconductor substrates.

Auditory brainstem implants provide sound information by direct stimulation of the cochlear nucleus to patients with dysfunctional or absent cranial nerve VIII. In contrast to patients with cochlear implants, the use of the auditory brainstem implants is less successful. This cannot be fully explained by the difference location of stimulation but a rather unspecific neuronal stimulation.

Isolation and characterization of neural stem cells from the neonatal rat cochlear nucleus.

Neural stem cells have been identified in multiple parts of the postnatal mammalian brain, as well as in the inner ear. No investigation of potential neural stem cells in the cochlear nucleus has yet been performed. The aim of this study was to investigate potential neural stem cells from the cochlear nucleus by neurosphere assay and in histological sections to prove their capacity for self-renewal and for differentiation into progenitor cells and cells of the neuronal lineage.

Cytotoxic, genotoxic and pro-inflammatory effects of zinc oxide nanoparticles in human nasal mucosa cells in vitro.

Despite increasing application of zinc oxide nanoparticles (ZnO-NPs) for industrial purposes, data about potential toxic properties is contradictory. The current study focused on the cyto- and genotoxicity of ZnO-NPs in comparison to ZnO powder in primary human nasal mucosa cells cultured in the air-liquid interface. Additionally, IL-8 secretion as a marker for pro-inflammatory effects was measured.

Silver nanoparticles: evaluation of DNA damage, toxicity and functional impairment in human mesenchymal stem cells.

Silver nanoparticles (Ag-NPs) are the most frequent commercialized nanomaterial currently. Due to a distinct lack of information on hazardous properties of Ag-NPs in human cells, a study was conducted to evaluate Ag-NP induced DNA damage, cell death and functional impairment in human mesenchymal stem cells (hMSCs). Initially, Ag-NPs and their cellular distribution were characterized by transmission electron microscopy (TEM).

BMSC enhance the survival of paclitaxel treated squamous cell carcinoma cells in vitro.

The 5-year survival rate of patients suffering from head and neck squamous cell carcinoma (HNSCC) is unsatisfying despite the advances in carcinoma treatment. Recent studies suggest that stem cells can be used as a gene therapy carrier for cancer treatment. Stem cells produce different cytokines such as growth factors in a paracrine manner and cancer cells may show drug resistance in the presence of such growth factors.

Zinc oxide nanoparticles induce photocatalytic cell death in human head and neck squamous cell carcinoma cell lines in vitro.

The aim of this study was to determine the photocatalytic effects of zinc oxide (ZnO) NPs in combination with UVA-1 in human head and neck squamous cell carcinoma (HNSCC) cell lines in vitro. NP characteristics and intracellular distribution were described by transmission electron microscopy (TEM). After pre-incubation with ZnO NPs in concentrations of 0.

Multipotent stromal cells for autologous cell therapy approaches in the guinea pig model.

Multipotent stromal cells have become of increasing interest due to their potential to provide therapeutic approaches for autologous tissue repair. However, these cells are not well defined in the guinea pig, which represents an important model in hearing research. Adipose-tissue-derived stem cells (ADSC) and bone-marrow-derived stem cells (BMSC) were isolated from different donor sites, and growth curves were generated to judge the proliferation potential.