In vitro antifungal and physicochemical properties of polymerized acrylic resin containing strontium-modified phosphate-based glass.

Acrylic resins are widely used as the main components in removable orthodontic appliances. However, poor oral hygiene and maintenance of orthodontic appliances provide a suitable environment for the growth of pathogenic microorganisms. In this study, strontium-modified phosphate-based glass (Sr-PBG) was added to orthodontic acrylic resin at 0% (control), 3.75%, 7.5%, and 15% by weight to evaluate the surface and physicochemical properties of the novel material and its in vitro antifungal effect against Candida albicans (C. albicans). Surface microhardness and contact angle did not vary between the control and 3.75% Sr-PBG groups (p > 0.05), and the flexural strength was lower in the experimental groups than in the control group (p < 0.05), but no difference was found with Sr-PBG content (p > 0.05). All experimental groups showed an antifungal effect at 24 and 48 h compared to that in the control group (p < 0.05). This study demonstrated that 3.75% Sr-PBG exhibits antifungal effects against C. albicans along with suitable physicochemical properties, which may help to minimize the risk of adverse effects associated with harmful microbial living on removable orthodontic appliances and promote the use of various materials.

Identification of the dichotomous role of age-related LCK in calorie restriction revealed by integrative analysis of cDNA microarray and interactome.

Among the many experimental paradigms used for the investigation of aging, the calorie restriction (CR) model has been proven to be the most useful in gerontological research. Exploration of the mechanisms underlying CR has produced a wealth of data. To identify key molecules controlled by aging and CR, we integrated data from 84 mouse and rat cDNA microarrays with a protein-protein interaction network. On the basis of this integrative analysis, we selected three genes that are upregulated in aging but downregulated by CR and two genes that are downregulated in aging but upregulated by CR. One of these key molecules is lymphocyte-specific protein tyrosine kinase (LCK). To further confirm this result on LCK, we performed a series of experiments in vitro and in vivo using kidneys obtained from aged ad libitum-fed and CR rats. Our major significant findings are as follows: (1) identification of LCK as a key molecule using integrative analysis; (2) confirmation that the age-related increase in LCK was modulated by CR and that protein tyrosine kinase activity was decreased using a LCK-specific inhibitor; and (3) upregulation of LCK leads to NF-κB activation in a ONOO(-) generation-dependent manner, which is modulated by CR. These results indicate that LCK could be considered a target attenuated by the anti-aging effects of CR. Integrative analysis of cDNA microarray and interactome data are powerful tools for identifying target molecules that are involved in the aging process and modulated by CR.