Indirect immunofluorescence technique to study expression of toll-like receptor 4 in chronic periodontitis.

AIM: The aim of this study was to analyze the expression level and localization of Toll-like receptor (TLR) 4 in gingival samples of healthy and chronic periodontitis subjects by indirect immunofluorescence technique (IFT). MATERIALS AND METHODS: In this study, gingival tissue samples were obtained from 25 healthy and 25 periodontitis individuals. The tissues were processed and the initial characterization was done by hematoxylin and eosin staining. The expression and localization of the TLR4 receptor were determined in the epithelial and connective layer cells of the gingival tissue using the indirect IFT. Immunofluorescence images were acquired and quantitative expression of TLRs was analyzed by calculating the percentage of cells showing positive results. RESULTS: We found that the healthy control group exhibited significantly lower values of TLR4 expression in comparison with the periodontitis patients. We also found that in patients with periodontitis the concentration of TLR4 was higher in the epithelium as compared to their expression in connective tissue cells. CONCLUSIONS: These data suggested a definite involvement of TLR4 in initiating and progression of an inflammatory response in periodontitis.

Analysis of Expression and Localization of TLR-2 by Immunofluorescent Technique in Healthy and Inflammed Oral Tissues.

INTRODUCTION: Toll-like receptors (TLRs) are an important component of immune system. Among them, TLR-2 plays a dominant role in the oral tissues in initiating inflammation in chronic periodontitis. Not many studies have been done on quantitative expression of TLR-2 by using immunofluorescent techniques (IFT) in oral tissues. In this study, the expression and localisation of TLR-2 were detected in gingival tissues of chronic periodontitis patients and healthy individuals. MATERIAL AND METHODS: Immuno Fluorescent Technique (IFT) was used for the expression and localization of TLR-2 in gingival tissue samples from 25 chronic periodontitis patients and from 25 healthy controls. Haematoxylin and Eosin staining was also done for all the samples to determine the histological characteristics of the gingival tissue samples. RESULT: Both healthy and periodontitis gingival tissues expressed TLR-2. We found that the expression level of TLR-2 was higher in all the periodontitis patients than in healthy individuals. We also found out that the expression of TLR-2 was higher in the epithelial cells than in the connective tissue cells. CONCLUSION: These data suggest a definite involvement of TLR-2 in initiating an inflammatory response in periodontal tissues. More studies are required to define the mechanisms and expression levels of TLR-2 in oral health and diseases.

Effects of diesel exhaust particles on human alveolar macrophage ability to secrete inflammatory mediators in response to lipopolysaccharide.

Ambient particulate matter (PM) has been shown to be associated with mortality and morbidity. Diesel exhaust particles (DEP) contribute to ambient PM. Alveolar macrophages (AM) are important targets for PM effects in the lung. The effects of DEP exposure on human AM response to lipopolysachharide (LPS; from gram-negative bacteria) challenge in vitro were determined by monitoring the production of interleukin 8 (IL-8), tumor necrosis factor-alpha (TNF-alpha) and prostaglandin E(2) (PGE(2)). The roles of organic compounds and carbonaceous core of DEP in response to LPS were evaluated by comparing the DEPs effect to that of carbon black (CB), a carbonaceous particle with few adsorbed organic compounds. AMs were exposed in vitro to Standard Reference Material (SRM) DEP 2975, SRM DEP 1650, SRM 1975 (a dichloromethane extract of SRM DEP 2975) and CB particles for 24 h. DEPs induced a decreased secretion of IL-8, TNF-alpha and PGE(2) in response to a subsequent LPS stimulation. DEPs also show suppressive effect on the release of inflammatory mediators when stimulated with lipoteichoic acid, a product of gram positive bacteria. In summary, in vitro exposure of human AM to DEPs significantly suppress AM responsiveness to gram-negative and positive bacterial products, which may be a contributing factor to the impairment of pulmonary defense.

Modeling and optimising alcohol production by fermentation of dextrose-xylose mixed feed using a fluorosensor.

Dextrose with differing amounts of xylose (mixed substrate medium) has been fermented at 28 degree Celsius with sacchromyces cerevisiae (Baker's Yeast) as seeding. The progress of the reaction was recorded by measuring the fluorescent signal due to intracellular reduced nicotinamide adenine di nucleotide (NADH) present in the cells with a Dr. Ingold (Switzerland) fluorosensor which has an excitation wavelength of 360 nm and measurement wavelength of 450 nm. The concentration of xylose in the xylose-dextrose feed was varied from 0.7% to 5.0% by weight. The optimum concentration of xylose at which the production of alcohol was a maximum was found to be 3.4 percent xylose. The fluorescent voltage data for different concentration of xylose fitted a first order model with an average absolute deviation of less than one percent. Development of this model is useful in design of model predictive controllers.