Biological Properties of the Aggregated Form of Chitosan Magnetic Nanoparticle.

Background/aim: Chitosan-coated iron oxide nanoparticles (Chi-NP) have gained attention because of their biocompatibility, biodegradability, low toxicity and targetability under magnetic field. In this study, we investigated various biological properties of Chi-NP.

Materials And Methods: Chi-NP was prepared by mixing magnetic NP with chitosan FL-80.

Changes in Metabolic Profiles of Human Oral Cells by Benzylidene Ascorbates and Eugenol.

Sodium-5,6-benzylidene-L-ascorbate (SBA), and its component units, benzaldehyde (BA) and sodium ascorbate (SA), are known to exert antitumor activity, while eugenol exerts anti-inflammatory activity. To narrow down their intracellular targets, metabolomic analysis was performed. Viable cell number was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method.

Induction of Apoptosis in Human Oral Keratinocyte by Doxorubicin.

Background/aim: We have previously reported that doxorubicin (DXR) showed much higher cytotoxicity against human oral squamous cell carcinoma cell lines compared to normal human mesenchymal normal oral cells (gingival fibroblast, periodontal ligament fibroblast, pulp cell), yielding high tumor-specificity. However, we unexpectedly found that doxorubicin showed potent cytotoxicity against human normal oral keratinocytes and primary gingival epithelial cells. In the present study, we investigated the reproducibility, underlining mechanisms and generality of this unexpected finding.

Effects of 3-styrylchromones on metabolic profiles and cell death in oral squamous cell carcinoma cells.

4-1-benzopyran-4-ones (chromones) are important naturally-distributing compounds. As compared with flavones, isoflavones and 2-styrylchromones, there are only few papers of 3-styrylchromones that have been published. We have previously reported that among fifteen 3-styrylchromone derivatives, three new synthetic compounds that have OCH group at the C-6 position of chromone ring, ()-3-(4-hydroxystyryl)-6-methoxy-4-chromen-4-one (compound ), ()-6-methoxy-3-(4-methoxystyryl)-4-chromen-4-one (compound ), ()-6-methoxy-3-(3,4,5-trimethoxystyryl)-4-chromen-4-one (compound ) showed much higher cytotoxicities against four epithelial human oral squamous cell carcinoma (OSCC) lines than human normal oral mesenchymal cells.

Effects of TiO2 nano glass ionomer cements against normal and cancer oral cells.

Background/aim: Incorporation of nanoparticles (NPs) into the glass ionomer cements (GICs) is known to improve their mechanical and antibacterial properties. The present study aimed to investigate the possible cytotoxicity and pro-inflammation effect of three different powdered GICs (base, core build and restorative) prepared with and without titanium dioxide (TiO2) nanoparticles.

Materials And Methods: Each GIC was blended with TiO2 nanopowder, anatase phase, particle size <25 nm at 3% and 5% (w/w), and the GIC blocks of cements were prepared in a metal mold.

3D dynamic pituitary MR imaging with CAIPIRINHA: initial experience and comparison with 2D dynamic MR imaging.

Objectives: To evaluate the validity of 3D dynamic pituitary MR imaging with controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA), with special emphasis on demarcation of pituitary posterior lobe and stalk.

Methods: Participants comprised 32 patients who underwent dynamic pituitary MR imaging due to pituitary or parasellar lesions. 3D dynamic MR with CAIPIRINHA was performed at 3T with 20-s-interval, precontrast, 1st to 5th dynamic images.

Cytotoxicity and pro-inflammatory action of chemo-mechanical caries-removal agents against oral cells.

Background: Chemo-mechanical caries removal eliminates the outermost portion of the infected layer, leaving behind healthy dentine surfaces, with scarce dental tissue damage; however, the safety of caries solvents has not been established. The aim of the present study was to investigate the possible cytotoxicity of two popular chemo-mechanical caries removal agents.

Materials And Methods: The cytotoxicity of Carisolv, Papacarie Duo and control vehicle solution (0.

Quantitative structure-activity relationship analysis of cytotoxicity and anti-UV activity of 2-aminotropones.

Background: We newly synthesized twenty 2-aminotropones with different lengths of methylene units, with or without introduction of isopropyl group at C-4 position of the cycloheptatriene ring, which were then subjected to quantitative structure-activity relationship (QSAR) analysis.

Materials And Methods: Viable cell number was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The tumor specificity was determined by the ratio of the mean CC50 (50% cytotoxic concentration) for the normal cells (human gingival fibroblast, HGF) to that of the human oral squamous cell carcinoma (OSCC) cell line (Ca9-22) derived from gingival tissue.

Induction of prostaglandin E2 production by TiO2 nanoparticles in human gingival fibroblast.

Background: Despite recent progress in the research of nanoparticles (NPs) spanning in many scientific fields, study of NPs in dentistry is limited. This triggered us to investigate the effect of TiO2 NPs on the drug-sensitivity of oral squamous cell carcinoma and inflammation of human gingival fibroblasts (HGFs).

Materials And Methods: The number of viable HGF cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method.

Effects of TiO2 nanoparticles on cytotoxic action of chemotherapeutic drugs against a human oral squamous cell carcinoma cell line.

Background: Despite the rapid development of nanotechnology, the biological significance of TiO2 nanoparticles (NPs), possibly released from dental materials, is not well-understood. We investigated the effect of TiO2 NPs on the sensitivity of human oral squamous cell carcinoma (OSCC) cell line (HSC-2) to five popular chemotherapeutic agents.

Materials And Methods: Viable cell number was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method.

Non-apoptotic cell death induced by nutritional starvation in J774.1 mouse macrophage-like cell line.

The growth and amino acid utilization of a mouse macrophage-like cell line J774.1 was investigated in two different culture media supplemented with 10% fetal bovine serum (FBS). The J774.

Tumor-specific cytotoxicity and type of cell death induced by gefitinib in oral squamous cell carcinoma cell lines.

Gefitinib is an orally active, selective epidermal growth factor receptor-tyrosine kinase inhibitor. The present study was aimed at evaluating the antitumor activity of gefitinib alone or in combination with other antitumor agents. Gefitinib showed higher cytotoxicity against five human tumor cell lines (HSC-2, HSC-3, HSC-4, T98G and U87MG) than against three human normal oral cells (gingival fibroblast HGF, pulp cell HPC and periodontal ligament fibroblast HPLF).

Cell death induced by nutritional starvation in mouse macrophage-like RAW264.7 cells.

Amino acid utilization of mouse macrophage-like RAW264.7 cells was investigated. During the logarithmic growth stage, RAW264.

Tumor-specific cytotoxicity and type of cell death induced by peplomycin in oral squamous cell carcinoma cell lines.

The antitumor antibiotic peplomycin showed higher cytostatic antiproliferative effect on five cultured human oral squamous cell carcinoma (OSCC) cell lines (HSC-2, HSC-3, HSC-4, Ca9-22 and NA), as compared with three human oral normal cells (gingival fibroblast HGF, pulp cell HPC and periodontal ligament fibroblast HPLF). Although the antiproliferative activity of peplomycin declined with increasing cell density, peplomycin showed tumor-specific cytotoxicity at any cell density. The five OSCC cell lines showed considerable differences in sensitivity against peplomycin; the HSC-2 cells were the most sensitive, followed by the NA, HSC-3, Ca9-22 and HSC-4 cells.

Tumor-specific cytotoxicity and type of cell death induced by benzocycloheptoxazines in human tumor cell lines.

Twenty-six benzocycloheptoxazine derivatives were investigated for their tumor-specific cytotoxicity and apoptosis-inducing activity against three human normal cells (gingival fibroblast HGF, pulp cell HPC, periodontal ligament fibroblast HPLF) and four human tumor cell lines (squamous cell carcinoma HSC-2, HSC-3, HSC-4, promyelocytic leukemia HL-60). Benzo[b]cyclohepta[e][1,4]thiazine [1] exhibited very weak cytotoxicity, whereas its 6,8,10-tribromo derivative [3] exhibited higher cytotoxicity and tumor specificity (TS = 5.6).

Tumor-specific cytotoxicity and type of cell death induced by beta-cyclodextrin benzaldehyde inclusion compound.

The cytotoxicity of beta-cyclodextrin benzaldehyde inclusion compound (CDBA) against human normal and cancer cell lines was investigated. CDBA showed slightly higher cytotoxicity against human tumor cell lines, as compared to normal cells, with a tumor-specificity index of 2.2.

Rapid changes in amino acid and polyamine metabolism during copper-induced cell death of human gingival fibroblast.

There are very few studies on the interaction between dental alloys and oral tissues. The effect of direct contact with copper (Cu) on the cellular function of human gingival fibroblast (HGF) derived from the periodontal tissues was investigated. When HGF cells were inoculated onto a Cu plate, the viability of HGF cells immediately declined.

Tumor-specificity and type of cell death induced by trihaloacetylazulenes in human tumor cell lines.

Twenty trihaloacetylazulene derivatives with one atom of fluorine, chlorine, bromine or iodine was investigated for their tumor-specific cytotoxicity and apoptosis-inducing activity against three human normal cells (gingival fibroblast, HGF; pulp cell, HPC; periodontal ligament fibroblast, HPLF) and four human tumor cell lines (squamous cell carcinoma, HSC-2, HSC-3, HSC-4; promyelocytic leukemia, HL-60). There was no apparent difference in the cytotoxic activity between 2-methoxyazulenes [1a-1e, 2a-2e] and 2-ethoxyazulenes [3a-3e, 4a-4e]. Trichloroacetylazulenes [2a-2e, 4a-4e] generally showed higher cytotoxicity and tumor-specificity (expressed as a TS value) as compared with the corresponding trifluoroacetylazulenes [1a-1e, 3a-3e].

Enhancement of cytotoxic activity of sodium fluoride against human periodontal ligament fibroblasts by water pressure.

Whether or not water pressure enhances the cytotoxic activity of sodium fluoride (NaF) against human periodontal ligament fibroblast (HPLF) was investigated. Loading with water pressure (up to 5 g) alone did not affect the cell proliferation, but significantly enhanced the cytotoxic activity of millimolar concentrations of NaF. Cytotoxic activity of NaF was reduced by supplementation with Ca2+, whereas it was enhanced by removal of Ca2+ from the culture medium.

Cytotoxic activity of selected trifluoromethyl ketones against oral tumor cells.

Several trifluoromethyl ketones (TF1-4) and related non-fluorinated ketones (TF5 and 6) were tested for their relative cytotoxicity on four human tumor cell lines (oral squamous cell carcinoma HSC-2, HSC-3, HSC-4 and promyelocytic leukemia HL-60) and three normal human cells [gingival fibroblasts (HGF), pulp cells (HPC) and periodontal ligament fibroblasts (HPLF)]. Trifluoromethylated a-diketone (TF1, CF3COCOPh) and alpha-hydroxy ketones (TF2, CF3CH(OH)COPh; TF3, CF3CH(OH)COCH2Ph) showed higher tumor-specific cytotoxic activity than the corresponding non-fluorinated analogs (TF5, CH3COCOPh; TF6, CH3CH(OH)COPh), while the anti-tumor potency of trifluoromethyl ketone (TF4, CF3COCH2Ph) was lower. Among four tumor cell lines, HL-60 cells were the most sensitive to TF1-4, followed by HSC-2 and HSC-3 cells.

Re-evaluation of tumor-specific cytotoxicity of mitomycin C, bleomycin and peplomycin.

Three antitumor antibiotics, mitomycin C, bleomycin sulfate and peplomycin sulfate, were compared for their tumor-specific cytotoxicity, using human oral squamous cell lines (HSC-2, HSC-3, HSC-4, Ca9-22 and NA), human promyelocytic leukemic cell line HL-60 and human normal oral cell types (gingival fibroblast HGF, pulp cell HPC and periodontal ligament fibroblast HPLF). Among these three compounds, mitomycin C showed the highest tumor-specificity, due to its higher cytotoxic activity against human oral tumor cell lines than bleomycin and peplomycin. However, there was considerable variation of drug sensitivity among the six tumor cell lines.

Induction of non-apoptotic cell death by morphinone in human promyelocytic leukemia HL-60 cells.

As previously suggested, codeinone (oxidation product of codeine) induces non-apoptotic cell death, characterized by marginal caspase activation and the lack of DNA fragmentation in HL-60 human promyelocytic leukemia cells, which was inhibited by N-acetyl-L-cysteine. Whether, morphinone, an oxidative metabolite of morphine, also induced a similar type of cell death in HL-60 cells was investigated. Morphinone showed slightly higher cytotoxic activity against human tumor cell lines (oral squamous cell carcinoma HSC-2, HSC-3, HSC-4, NA, Ca9-22, promyelocytic leukemia HL-60, cervical carcinoma HeLa) than against normal oral human cells (gingival fibroblast HGF, pulp cells HPC, periodontal ligament fibroblast HPLF).

Biological impact of contact with metals on cells.

In order to investigate the in vivo effect of metals used in dentistry, we investigated the effect of direct contact with metal plates (20 x 20 x 0.5 mm3) made of gold (Au), silver (Ag), copper (Cu) or palladium (Pd) on human promyelocytic leukemic HL-60 cells grown in RPMI1640 medium supplemented with 10% fetal bovine serum. When 0.