Autoregulation of periodontal ligament cell phenotype and functions by transforming growth factor-beta1.

During orthodontic tooth movement, mechanical forces acting on periodontal ligament (PDL) cells induce the synthesis of mediators which alter the growth, differentiation, and secretory functions of cells of the PDL. Since the cells of the PDL represent a heterogeneous population, we examined mechanically stress-induced cytokine profiles in three separate clones of human osteoblast-like PDL cells. Of the four pro-inflammatory cytokines investigated, only IL-6 and TGF-beta1 were up-regulated in response to mechanical stress.

Regulation of periodontal ligament cell functions by interleukin-1beta.

Periodontal ligament (PDL) cells maintain the attachment of the tooth to alveolar bone. These cells reside at a site in which they are challenged frequently by bacterial products and proinflammatory cytokines, such as interleukin-1beta (IL-1beta), during infections. In our initial studies we observed that IL-1beta down-regulates the osteoblast-like characteristics of PDL cells in vitro.

Synthesis of proinflammatory cytokines by human gingival fibroblasts in response to lipopolysaccharides and interleukin-1 beta.

We have examined the ability of gingival fibroblasts (GF) to participate in inflammatory response and function as accessory immune cells. The accessory immune function of GF cells was evaluated by their ability to elaborate proinflammatory cytokines following stimulation with lipopolysaccharides and interleukin-1 beta (IL-1 beta). Using three separate clonally derived and characterized human gingival fibroblast (GF) cell lines, we demonstrate that LPS from Actinobacillus actinomycetemcomitans (Aa) and Escherichia coli (Ec) induce mRNA and synthesis of proinflammatory cytokines, IL-1 beta, IL-6 and IL-8.

LPS responsiveness in periodontal ligament cells is regulated by tumor necrosis factor-alpha.

Gingival fibroblasts function as accessory immune cells and are capable of synthesizing cytokines in response to lipopolysaccharides (LPS) from Gram-negative microbes. Recently, we have isolated, cloned, and characterized two cell lines which exhibit characteristics of periodontal ligament (PDL) cells. In this report, we demonstrate that PDL cells showing osteoblast-like phenotype are not LPS-responsive cells.

Toxicity testing of sealants: a tissue implant study.

The toxicity of pit and fisure sealants implanted into the subcutaneous tissues of guinea pigs was tested using the protocol for toxicity testing derived from the ADA/ANSI Document No. 41, 1982. The materials tested were Delton autopolymerized and photopolymerized, and Concise White autopolymerized and photopolymerized.

Antifungal properties of 2-n-alkyn-1-ols.

Fourteen 2-n-alkynols (C3-C14, C16, and C18) were tested against Aspergillus oryzae, Aspergillus niger, Trichoderma viride, and Myrothecium verrucaria in Sabouraud dextrose agar at pH 5.6 and 7.0.

Use of lipids to potentiate the antibacterial activity of aminoglycosides.

Linolenyl alcohol has been shown to inhibit the in vitro growth of several species of gram-positive bacteria. Since the double bonds in linolenyl alcohol could undergo autooxidation, the antimicrobial activities of saturated primary alcohols of similar molecular sizes against Streptococcus mutans BHT were evaluated. Tridecan-1-ol was identified as the most active compound, eliciting a bacteriostatic effect at concentrations at which growth occurred in the presence of other saturated alcohols or linolenyl alcohol.

Effect of 2-alkynoic acids on in vitro growth of bacterial and mammalian cells.

3-Decynoyl-N-acetylcystamine is known to inhibit the in vitro growth of Escherichia coli but not of yeasts or mammalian cells. Neither the free acid nor the 2 positional isomer is active (L. R.

Effect of linolenyl alcohol on the in-vitro growth of the oral bacterium Streptococcus mutans.

The effect of primary aliphatic alcohols of varying chain length and degree of unsaturation on bacterial growth was assessed, using Strep. mutans BHT as the main test organism. Unsaturated alcohols, linoleyl and linolenyl, effectively inhibited bacterial growth.

Scanning electron microscopy of epithelial cells grown on enamel, glass and implant materials.

The purpose of the present study was to examine with scanning electron microscopy gingival epithelial cells grown in cell culture on tooth enamel, glass, Vitallium, titanium and vitreous carbon. SGL (Smulow-Glickman) gingival epithelial cells were grown for 5 days and processed using a critical point drying apparatus. Scanning electron microscopy carried out at X 1500 magnification revealed that the gingival epithelial cells gres equally well on all materials on either smooth or rough (sand-blasted) surfaces.