Mauricio Garrido

Pro-oxidant status and matrix metalloproteinases in apical lesions and gingival crevicular fluid as potential biomarkers for asymptomatic apical periodontitis and endodontic treatment response

BackgroundOxidative stress and matrix metalloproteinases -9 and -2 are involved in periodontal breakdown, whereas gingival crevicular fluid has been reported to reflect apical status. The aim of this study was to characterize oxidant balance and activity levels of MMP -2 and -9 in apical lesions and healthy periodontal ligament; and second, to determine whether potential changes in oxidant balance were reflected in gingival crevicular fluid from asymptomatic apical periodontitis (AAP)-affected teeth at baseline and after endodontic treatment.MethodsPatients with clinical diagnosis of AAP and healthy volunteers having indication of tooth extraction were recruited. Apical lesions and healthy periodontal ligaments, respectively, were homogenized or processed to obtain histological tissue sections. Matrix metalloproteinase -9 and -2 levels and/or activity were analyzed by Immunowestern blot, zymography and consecutive densitometric analysis, and their tissue localization was confirmed by immunohistochemistry. A second group of patients with AAP and indication of endodontic treatment was recruited. Gingival crevicular fluid was extracted from AAP-affected teeth at baseline, after endodontic treatment and healthy contralateral teeth. Total oxidant and antioxidant status were determined in homogenized tissue and GCF samples. Statistical analysis was performed using STATA v10 software with unpaired t test, Mann-Whitney test and Spearmans correlation.ResultsActivity of MMP-2 and MMP-9 along with oxidant status were higher in apical lesions (p < 0.05). Total oxidant status correlated positively with matrix metalloproteinase-2 and lesion size (p < 0.05). Gingival crevicular fluid showed significantly lower levels of total antioxidant status in diseased teeth at baseline compared to controls and endodontically-treated groups.ConclusionsApical lesions display an oxidant imbalance along with increased activity of matrix metalloproteinase-2 and -9 and might contribute to AAP progression. Oxidant imbalance can also be reflected in GCF from AAP-affected teeth and was restored to normal levels after conservative endodontic treatment. These mediators might be useful as potential biomarkers for chair-side complementary diagnostic of apical status in GCF.

Diagnostic accuracy for apical and chronic periodontitis biomarkers in gingival crevicular fluid: an exploratory study

AIM The aim of this study was to assess the levels and diagnostic accuracy of a set of potential biomarkers of periodontal tissue metabolism in gingival crevicular fluid (GCF) from patients with chronic periodontitis (CP) and asymptomatic apical periodontitis ( AAP). MATERIALS AND METHODS Thirty one GCF samples from 11 CP patients, 44 GCF samples from 38 AAP patients and 31 GCF samples from 13 healthy volunteers were obtained (N = 106). Matrix metalloproteinases (MMPs) -2 and -9 were determined by zymography; levels of MMP-8 by ELISA and IFMA and MPO by ELISA. IL-1, IL-6, TNFα, DKK-1, Osteonectin, Periostin, TRAP-5 and OPG were determined by a multiplex quantitative panel. Statistical analysis was performed using linear mixed-effects models. RESULTS The MMP-9 and MMP-8 were higher in CP, followed by AAP, versus healthy individuals (p < 0.05). ProMMP-2, MPO, IL-1, IL-6, PTN, TRAP-5 and OPG were significantly higher in CP when compared with AAP and healthy patients (p < 0.05). The highest diagnostic accuracies were observed for ProMMP-2, ProMMP-9, MMP-8 and TRAP-5 (AUC > 0.97) in CP, and for the active form of MMP-9 and MMP-8 (AUC > 0.90) in AAP. CONCLUSION Gingival crevicular fluid composition is modified by CP and AAP. MMP-9 and MMP-8 show diagnostic potential for CP and AAP, whereas MMP-2 and TRAP-5 are useful only for CP.

Chemokine Monocyte Chemoattractant Protein-3 in Progressive Periodontal Lesions in Patients With Chronic Periodontitis

BACKGROUND Chemokines are central in the activation and direction of leukocyte subsets to target tissues. However, the monocyte chemoattractant protein-3 (MCP-3) has not been associated with chronic periodontitis. Chronic periodontitis is an infection showing episodic supporting tissue destruction. The aim of this study is to determine the levels and expression of MCP-3 in periodontal sites characterized by active periodontal connective tissue destruction. METHODS The study population consisted of 15 patients with a progression of periodontitis (15 of 56 patients), 18 patients with chronic periodontitis, and 10 healthy subjects without periodontal disease. As determined by the tolerance method, the 15 patients with moderate to advanced chronic periodontitis showed a progression of periodontitis over a 4-month period. Periodontitis was characterized by at least six sites with a probing depth >or=5 mm, clinical attachment level >or=3 mm, and radiographic bone loss. Gingival crevicular fluid was collected using a paper strip. The total protein concentration was determined. An enzyme-linked immunosorbent assay was performed to determine the total amount of MCP-3, and an immunoWestern blot was conducted to assess molecular MCP-3 forms. To determine the MCP-3 expression by immunohistochemistry, gingival biopsies were obtained from patients with chronic periodontitis and healthy subjects during third-molar extraction surgery. Statistical analyses were performed using statistical software. Data were expressed as subject means +/- SD, using the chi(2) and Student t tests. RESULTS The total amount and concentration of chemokine MCP-3 were significantly higher in patients with chronic periodontitis than in healthy subjects (8.25 pg versus 0.53 pg, P = 0.006 and 2.95 pg/microl versus 0.45 pg/microl, P = 0.04, respectively). Active sites showed a significantly higher total amount and concentration of MCP-3 than inactive sites (11.12 versus 2.88 pg, P value = 0.005 and 3.95 versus 1.02, P value = 0.005, respectively). Western blot and immunohistochemical staining confirmed the presence of MCP-3 in periodontal disease, with observable differences between patients with chronic periodontitis and healthy subjects. CONCLUSIONS MCP-3 was highly expressed in patients with chronic periodontitis, particularly in those with progressive periodontal lesions. MCP-3 could be involved in the recruitment of inflammatory cells toward periodontal tissues during the progression of the disease.

The TH17 vs. TREG Imbalance in the Pathogenesis of Periodontitis: New Approach for Dichotomy TH1 vs. TH2

Abstract For decades several authors have directed their efforts to elucidate the nature of the immune response in periodontitis. The subject has been matter of controversy, and answers remain unclear. The present review intends to summarize the character of the inflammatory response in periodontitis, with emphasis on the T helper imbalance produced during the development of the disease.

Change of support using non-additive variables with Gibbs Sampler: Application to metallurgical recovery of sulphide ores

Abstract Flotation tests at laboratory scale describe the metallurgical behavior of the minerals that will be processed in the operational plant. This material is generally composed of ore and gangue minerals. These tests are usually scarce, expensive and sampled in large supports. This research proposes a methodology for the geostatistical modelling of metallurgical recovery, covering the change of support problems through additive auxiliary variables. The methodology consists of simulating these auxiliary variables using a Gibbs Sampler in order to infer the behavior of samples with smaller supports. This allows downscaling a large sample measurement into smaller ones, reproducing the variability at different scales considering the physical restrictions of additivity balance of the metallurgical recovery process. As a consequence, it is possible to apply conventional multivariate geostatistical tools to data at different supports, such as multivariable exploratory analysis, calculation of cross-variograms, multivariate estimations, among others. The methodology was tested using a drillhole database from an ore deposit, modelling recovery at a smaller support than that of the metallurgical tests. The support allowed for the use of the geochemical database, to consistently model the metal content in the feed and in the concentrate, in order to obtain a valid recovery model. Results show that downscaling the composite size reduces smoothing in the final model.

Oral fluid matrix metalloproteinase (MMP)-8 as a diagnostic tool in chronic periodontitis

Periodontal diseases that affect the marginal and apical periodontium result from the interaction between bacterial biofilm and the host response. Oral fluid biomarkers might aid clinical diagnosis. Matrix metalloproteinases (MMPs) are a family of 24 proteases that act in physiological and pathological conditions. They can degrade almost all extracellular matrix constituents and regulate inflammatory processes. They are mainly inhibited by tissue inhibitors of metalloproteinases. The aim of this study was to perform a current literature review with a special reference on the diagnostic and clinical utility of oral fluid MMPs, especially MMP-8, and their inhibitors in periodontal and oral diseases. MMP-8 is the main collagenolytic MMP detected in oral fluids, such as saliva, oral mouthrinse, gingival crevicular fluid, and peri-implant fluid. MMP-8, and potentially MMP-9, in oral fluids represent strong biomarker candidates associated especially with periodontal disease diagnosis, severity, progression, and follow-up. Additionally, they show diagnostic potential for systemic conditions, such as pregnancy, myo- cardial infarction, and smoking. A commercially available mouthrinse, active MMP-8 chair-side/ point-of-care lateral flow immunoassay, shows enough sensitivity and specificity to detect clinical signs of periodontitis. The current literature supports that high MMP-8 levels reflect the loss of periodontal supporting tissues rather than inflammation, representing a potentially useful side-

Expresión de Factor Estimulante de Colonias-1 (CSF-1) y Catepsina-K en Lesiones Periapicales

Periapical Lesions (PLs) represent an immunoinflammatory disease of infectious origin, characterized by periapical tissue destruction. PLs are linked to the expression of various inflammatory mediators: Colony Stimulating Factor-1 (CSF-1) that stimulates differentiation of osteoclast precursor cells and Cathepsin K, an enzyme associated with bone destruction, could be related to osteolysis during PL. The aim of this study was to characterize the expression of these mediators in inflammatory radicular cyst, periapical granuloma and healthy periodontal tissue. Materials and Methods: We selected 13 individuals with clinical diagnosis of Apical Periodontitis (AP) and indication of extraction. Healthy subjects having indication of extraction for orthodontic reasons were also included. After extraction, specimens were biopsied and histological diagnosis was made. Subsequently, immunohistochemical staining was carried out to identify the mediators in study, and finally the samples were examined in a light microscope. Results: CSF-1 and Cathepsin K expression was distributed similarly in apical granulomas and radicular cysts. They were mainly immunolocalized to inflammatory infiltrates. Also lining epithelium, cyst capsule, and vascular endothelium were mildly immunopositive. No immunoreactivity was observed in healthy periodontium. Conclusions: CSF-1 and Cathepsin K are expressed in PLs and may participate in the pathogenesis of AP. Rev. Clin. Periodoncia Implantol. Rehabil. Oral Vol. 2(3); 179-181, 2009.