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ABSTRACT: Viridans streptococci possess a family of immunologically and structurally related cell-surface proteins, termed antigen I/II, which may function as adhesins and enable oral streptococci to adhere to saliva-coated surfaces and matrix proteins. Here we used atomic force microscopy in the molecular force mode to measure the specific interaction forces between antigen I/II and two matrix proteins, collagen and fibronectin. These matrix proteins provide important binding sites for adherence of oral streptococcal in dentinal caries and endocarditis, respectively. Antigen I/II-coated cantilever tips were brought into contact with collagen- or fibronectin-coated silica coverslips. For the protein I/II-fibronectin interaction experiments, the mean strength of the last ruptures was 216 pN, with most of the detachments located around 125 pN. In antigen I/II-collagen interaction experiments, the mean strength of the last rupture forces corresponded to 136 pN, with the most frequent unbinding force around 75 pN. Thus, our findings definitely suggest that, under the present experimental conditions, antigen I/II binds more strongly to fibronectin than to type I collagen. This might be of relevance for the attachment of viridians streptococci to surfaces exposed to strong hydrodynamic shearing forces under in vivo conditions.
European Journal Of Oral Sciences 12/2010; 118(6):590-5. · 1.88 Impact Factor
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ABSTRACT: Chromogranin A is present in secretion granules of nerve, endocrine and immune cells and is a precursor of several peptides with antibacterial and antifungal properties at micromolar concentrations.Our aim in this prospective, double blind study, was to determine the expression of chromogranin A and its peptides at protein level in saliva of type 2 diabetic patients and thereby to obtain a new non-invasive diagnostic means for the future.Saliva was taken from 30 type 2 diabetic patients and 30 healthy individuals at the same time interval in the morning without any oral stimuli. Circadianic periodics in protein productions have been avoided. The presence of chromogranin A and its derived peptides was determined in whole saliva, after centrifugation at 40C for 12 min at 14 000 rpm, by SDS-PAGE electrophoresis and Immunoblotting (Western Blot). To ensure same protein concentrations Bradford protein quantification assay has been performed before.For the first time, we have determined an overexpression of chromogranin A in saliva of diabetic patients in 100% of the individuals. Chromogranin A, a circulating biomarker for epithelial tumours, is also overexpressed in saliva of type 2 diabetic patients. To confirm our results, more studies with a large amount of patients is necessary.
Bosnian journal of basic medical sciences / Udruzenje basicnih mediciniskih znanosti = Association of Basic Medical Sciences 02/2010; 10(1):2-8. · 0.25 Impact Factor
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ABSTRACT: Regenerative therapy with enamel matrix proteins derivative (EMD) was shown to induce periodontal regeneration in intrabony defects. However, the contribution of papilla preservation technique (PPT), to the clinical outcome of regenerative therapy is still not clarified. Therefore, we conducted the present study to evaluate clinically measurable results of a combined therapy by PPT and EMD in the treatment of isolated intrabony defects.
Sixty isolated intrabony defects in 25 patients were surgically assessed with EMD and PPT. The clinical parameters: clinical attachment level (CAL), probing depth (PD) and gingival recession (GR) were evaluated at baseline and at three years.
The primary outcome variable was CAL. The sites treated with enamel matrix proteins demonstrated mean CAL change from 6.6+/-1.2 mm to 3.4+/-1.3 mm (p<0.001) and the mean PD was reduced from 5.9+/-1.0 mm to 2.7+/-0.8 mm (p<0.001) after three years. The mean GR decreased from 0.71+/-1.2 mm to 0.64+/-1.1 mm (p<0.821).
The results of the present case cohort study indicate that PPT combined with EMD resulted in significant improvement of the clinical parameters in the treatment of intrabony defects in chronic periodontitis.
Stomatologija / issued by public institution "Odontologijos studija" ... [et al.] 01/2008; 10(1):22-6.
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ABSTRACT: Background, aims: The aim of our study was to investigate the patterns of several metalloproteinases (MMP-1, MMP-2 and MT1-MMP) mRNAs expression using a semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and to correlate them with clinical parameters and bacteriological diagnosis in healthy versus diseased human gingiva.Methods: To identify the cell origin of MMP production, in situ hybridization (ISH) was also performed for the MMPs on the same samples. 17 gingival biopsies were collected (13 affected by advanced periodontitis and 4 healthy used as controls) and plaque index, gingival index, pocket depth and bleeding on probing were measured. Subgingival microbial samples were also collected to be analysed by a DNA probe technique. The biopsies were processed both for RT-PCR and ISH. We also investigated a model for bacterial induced MMP expression in human gingival fibroblasts (HGF) infected by Eikenella corrodens.Results: We found an expression of the mRNA encoding MMP-1 only in diseased gingiva but at low levels relative to β-actin (mean±SD: diseased versus healthy: 0.013±0.024 versus 0). Although the frequencies and levels of mRNA encoding for MMP-2 or MT1-MMP are not significantly different between each group (mean±SD: 0.329±0.344 versus 0.137±0.219 for MMP-2; 0.485±0.374 versus 0.466±0.296 for MT1-MMP), using ISH, we observed an expression of both mRNAs in fibroblasts of pathological specimens at sites that histologically showed signs of chronic inflammation and connective tissue remodelling. In vitro infection of HGF by Eikenella corrodens stimulated 3-fold the production of the mRNA encoding MMP-2 while other mRNAs remained unchanged.Conclusion: Our results did not reveal significant differences in the expression of mRNAs encoding for the MMPs between healthy and periodontitis-affected patients, reflecting the great heterogeneity in the periodontal status of individuals. However, they indicate that gingival fibroblasts are an active source of MMP-2 production in response to a periopathogen.
Journal Of Clinical Periodontology 01/2001; 28(2):128 - 136. · 3.00 Impact Factor
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http://dx.doi.org/10.1051/mbcb/2010013.
