Biomedical subjects

C Rubini

Publications and source records attributed to C Rubini.

77 records · Page 5Linked to original sources

PubMedDate not supplied

Vascular endothelial growth factor and microvessel density around healthy and failing dental implants.

Inflammatory infiltrate may be important in the evolution of inflammatory processes involving peri-implant tissues. Angiogenesis is an important feature of inflammation and healing, but its role in the development and progression or in the healing of periodontal lesions has not been elucidated. Vascular endothelial growth factor (VEGF) is a potent inducer of endothelial cell proliferation. The aim of the present study was to conduct a comparative immunohistochemical evaluation of VEGF and microvessel density (MVD) in normal keratinized gingiva and in peri-implant soft tissues surrounding failing implants. Fifteen patients participated in this study. Ten biopsies were taken from healthy keratinized gingiva, and 10 were taken from peri-implant soft tissues surrounding failing non-submerged implants. In healthy sites, the endothelial lining cells of the vessels always tested positive for VEGF; also, VEGF intensity was high in most cases. Stromal cells were positive for VEGF in 70% to 90% of samples. The MVD was 60.250 +/- 5.123. In peri-implantitis samples, the cells of the inflammatory infiltrate were positive for VEGF in 80% to 100% of cases, and the VEGF intensity was low in all cases. The stromal cells were positive for VEGF in 90% to 100% of cases, and in most cases the intensity was low. The MVD was 101.800 +/- 11.256. The difference in MVD between healthy sites and peri-implantitis was statistically significant (P = .0158). Expression of VEGF was lower in peri-implantitis samples, and this difference was statistically significant (P = .0373). Because of its extensive presence, VEGF is probably a factor in both the maintenance of periodontal physiology and in the progression of peri-implant inflammatory disease.

Adult↗

PubMedDate not supplied

Evolution of the changes of the ileal pouch mucosa over a long follow-up period.

BACKGROUND/AIMS: The mucosa of the ileal pouch after restorative proctocolectomy develops relevant adaptative changes but the real mechanisms and the evolution over time of these alterations are still unclear. The aims of the present work were to study the distribution of the mucosal changes at different levels in the reservoir and to evaluate the evolution of these alterations over a long follow-up period. METHODOLOGY: The severity of chronic and acute inflammation, villous atrophy, colonic-type mucins production and proliferative index were evaluated in the bioptical specimens from 46 patients (30 males, 16 females, mean age 38 years) with functioning pouch. We compared the histology of the upper pouch mucosa with the lower one. Then we divided the 46 patients into Group A-24 patients with a median follow-up of 11 years (range 9-16); Group B-22 patients with a median follow-up of 4 years (range 2-8), comparing the results from the two groups. Finally we performed a prospective evaluation in the 24 patients who were controlled in 3 subsequent follow-ups (1993-1994, 1996-97, 1999-2000). RESULTS: At the topographic evaluation only the acute inflammation was significantly more pronounced in the lower pouch area (p = 0.031). All the morphological changes showed a trend of greater severity in the group A patients, in particular villous atrophy (p = 0.005) and colonic-like mucins secretion (p = 0.006). At the prospective evaluation, the chronic inflammation showed a significant progressive worsening over time (p = 0.011). CONCLUSIONS: Our experience showed that the transformation of the mucosa represents an "organ" response to the luminal environment and may progress over time.

Adult↗

PubMedDate not supplied

Scatter factor receptor (c-Met) as possible prognostic factor in patients with oral squamous cell carcinoma.

This report was performed to study the biological role of c-Met in oral tumorigenesis by analyzing its expression in relation to clinicopathological features. Seventy-three cases of oral squamous cell carcinoma and 10 of normal mucosa were analysed for c-Met expression by immunohistochemistry. Normal oral squamous epithelium showed absent or low membranous positivity in the intermediate (malpighian-spinous) layer. Fifty-seven cases (78%) of carcinoma showed immunopositivity, with a prevalently membranous positivity and scattered areas also showing a cytoplasmic localization. Sixteen cases of carcinoma (22%) showed no positivity for c-Met. Among positive tumours, well-differentiated areas showed low or absent cytoplasmic positivity, while low-differentiated areas showed both membranous and cytoplasmic positivity. There was no statistically significant correlation between c-Met expression and sex, recurrence, staging or grading. The frequency of lymph node metastases was higher in c-Met-positive tumours (17/57, 29%) than in c-Met-negative ones (4/16, 25%). When analysed for prognostic significance, patients with negative/reduced c-Met expression had better survival rates than patients with high expression. The difference between survival rates was statistically significant (p<0.05). These data suggest that c-Met expression may be useful to identify cases of oral squamous cell carcinoma with a more aggressive and invasive phenotype.

Adult↗

PubMedDate not supplied

Beta-catenin gene analysis in oral squamous cell carcinoma.

The molecular mechanisms involved in the development of oral squamous cell carcinomas (OSCC) are not yet well understood. Evidence of recent studies suggests that aberrant beta-catenin signalling may participate in the neoplastic transformation and that it is implicated in the development of several tumours. Beta-catenin is a component of the catenin family and plays a crucial role in cadherin mediated cell adhesion. However, it has recently been shown that beta-catenin is also involved in other functions such as intracellular signalling and the regulation of gene transcription. The aim of this study is to evaluate the presence of mutation in exon 3 of the beta-catenin gene in 20 OSCC cell lines. DNA was extracted using Qiagen Qiamp DNA minikit and a region encompassing the exon 3 of beta-catenin gene was amplified using a single PCR assay. The PCR products were analysed by SSCP and direct sequencing to detect any mutation of the gene. Most of the cell lines examined showed, by immunofluorescence, a beta-catenin delocalization. SSCP and sequence analysis of the PCR products did not show any mutation of the beta-catenin gene in any of the cell lines. In conclusion, although aberrant expressions or abnormal localization of beta-catenin have been detected in several OSCC cells, it appears that this finding has no relationship with beta-catenin gene mutations.

Carcinoma, Squamous Cell↗

PubMedDate not supplied

cGMP phosphodiesterase activity evaluation in human carcinoma of salivary glands.

The aim of this study was to evaluate differences of cGMP-PDE activity in salivary glands, between a control group and different benign tumour groups and, where present, with malign tumour groups. Endogen cGMP was evaluated too. The enzymatic reaction used the method of Spoto et al., with minor variations. The samples were organized in six groups: A (Adenolymphoma and Warthins tumour); B (Pleomorphic Adenoma); C (Basaloid Adenoma); D (Myoepitelioma). The control group was represented by healthy patients. In A and B groups, we have analyzed malign pathologies (Adenocarcinoma and Parotid Lymphoma) The benign tumours have more activity than controls, especially in Myoepitelioma (D) but with a decrement in the C group, which presents lower values of cGMP than the other three groups, where the concentration is similar. Between A and B groups, the activity values of malign tumours are similar, higher than controls and than the other benign pathologies, but not higher than in myoepitelioma. The cyclic concentration is similar for malign pathologies, with concentrations lower than controls, similar to Basaloid Adenoma (C).

3',5'-Cyclic-GMP Phosphodiesterases↗