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Biomedical subjects

A Piattelli

Publications and source records attributed to A Piattelli.

At least 19 recordsLinked to original sources
PubMed2006

cAMP phosphodiesterase activity evaluation in human carcinoma of salivary glands.

The aim of this study was to evaluate differences of cAMP-PDE activity in human salivary glands, between a control group and some different benign tumours groups and, where present, with 2 malignant tumors groups. The value of the enzymatic activity in the groups analysed was 50% lower than control samples. The differences between the control group (82 +/- 7.9 nmols/mg of protein) and the 3 pathologic groups (Benign A: 44 +/- 6.2; Malignant A: 40 +/- 16; Benign B: 40 +/- 14.2; Malign A: 9.1; Benign C: 22 nmols/mg of protein) are statistically significant.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2006

CD10 expression in stromal cells of oral cavity squamous cell carcinoma: a clinic and pathologic correlation.

OBJECTIVE: CD10 is expressed on the majority of follicle-center lymphomas and Burkitt lymphomas. CD10 has also been shown to be present in a variety of other neoplasms. DESIGN: The aim of this study was a correlation of CD10 and several parameters: age, tumor size, presence of lymph node metastases, clinic stage, histologic grading, presence of local recurrences. MATERIALS AND METHODS: The tissues of 77 consecutive patients with oral cavity squamous cell carcinoma were evaluated using immunostaining with monoclonal antibody for CD10. MAIN OUTCOME MEASURES: Highly significant correlations were found with the lymph node status, the presence of local recurrences and the histologic grading. The presence of CD10-positive cells was not correlated with the age of patients, tumor size and clinic stage. RESULTS: The results of the present study show that in oral squamous cell carcinoma CD10 positivity is an indicator of worse prognosis. Another strong correlation was found with the presence of local recurrences. Also the histologic grade was significantly correlated with the CD10 positivity. CONCLUSION: Our results point to the fact that CD10 expression can, perhaps, have an important role in tumor invasion, probably facilitating the occurrence of metastases.

Adult↗
PubMed2006

Effects of Emdogain on osteoblast gene expression.

OBJECTIVE: Emdogain (EMD) is a protein extract purified from porcine enamel and has been introduced in clinical practice to obtain periodontal regeneration. EMD is composed mainly of amelogenins (90%), while the remaining 10% is composed of non-amelogenin enamel matrix proteins such as enamelins, tuftelin, amelin and ameloblastin. Enamel matrix proteins seem to be involved in root formation. EMD has been reported to promote proliferation, migration, adhesion and differentiation of cells associated with healing periodontal tissues in vivo. DESIGN: How this protein acts on osteoblasts is poorly understood. We therefore attempted to address this question by using a microarray technique to identify genes that are differently regulated in osteoblasts exposed to enamel matrix proteins. RESULTS: By using DNA microarrays containing 20,000 genes, we identified several upregulated and downregulated genes in the osteoblast-like cell line (MG-63) cultured with enamel matrix proteins (Emd). The differentially expressed genes cover a broad range of functional activities: (i) signaling transduction, (ii) transcription, (iii) translation, (iv) cell cycle regulation, proliferation and apoptosis, (v) immune system, (vi) vesicular transport and lysosome activity, and (vii) cytoskeleton, cell adhesion and extracellular matrix production. CONCLUSIONS: The data reported are the first genome-wide scan of the effect of enamel matrix proteins on osteoblast-like cells. These results can contribute to our understanding of the molecular mechanisms of bone regeneration and as a model for comparing other materials with similar clinical effects.

Animals↗
PubMed2006

Microvessel density and vascular endothelial growth factor expression in sinus augmentation using Bio-Oss.

AIM: The aim of this study was to evaluate microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression in sinus augmentation with Bio-Oss. METHODS: Twenty patients participated in this study. The sinuses were filled with 100% Bio-Oss. Implants were inserted after 3 months in group A, and 6 months in group B. A trephine was used to harvest bone cores. As control, the pre-existing subantral bone was used. RESULTS: The mean MVD in control bone was 23.6 +/- 1.8. In the sites augmented with Bio-Oss, at 3 months, the MVD was 23.3 +/- 2.1, while in the sites retrieved at 6 months the MVD was 29.5 +/- 2.4. The difference in MVD between the control bone and group A was not statistically significant. The difference between the control bone and group B was statistically significant (P < 0.05). The statistical analysis showed that the difference in MVD between group A and group B was statistically significant (P < 0.05). CONCLUSIONS: Bio-Oss seemed to induce an increase in MVD that reached a higher value after 6 months. The percentage of vessels positive to VEGF was higher in group A than in group B. Our data also showed a higher percentage of vessel and stromal cells positive to VEGF and higher MVD values in areas where there was newly formed bone compared with areas where maturation processes were occuring, and this fact could point to a close spatial relationship between angiogenesis and osteogenesis.

Adult↗
PubMed2005

p63 expression in odontogenic cysts.

A total of 123 cases of odontogenic cysts, distributed as follows: 30 follicular (FC), 35 radicular (RC), 53 keratocysts, 1 glandular odontogenic and 4 calcifying odontogenic cysts, were analysed by immunohistochemistry for expression of p63, a component of p53 protein family. In RCs p63 positivity was not only in basal and parabasal layers but also in the intermediate layer and about 1/3 of cases displayed a percentage of stained cells comprised between 0 and <5%, and about 2/3 between >5% and <50%. In FCs positivity was confined to basal and parabasal layers of the epithelium and in the majority of FCs the stained cells were comprised between 0 and <5%. OKCs displayed the most intense and diffuse p63 labeling. In conclusion, these data suggest that p63 expression may be useful to identify cysts type with more aggressive and invasive phenotype supporting the hypothesis of a suprabasal proliferative compartment in OKCs.

DNA-Binding Proteins↗
PubMed2004

Transforming growth factor-beta 1 (TGF-beta 1) expression in normal healthy pulps and in those with irreversible pulpitis.

AIM: To evaluate the Transforming Growth Factor-beta 1 (TGF-beta 1) expression in normal healthy pulps and in those with irreversible pulpitis. METHODOLOGY: Twenty-three normal, healthy pulps were removed from mandibular third molars, and 20 pulps were retrieved from teeth with irreversible pulpitis. TGF-beta 1 was evaluated in the odontoblastic and subodontoblastic layers, in the stromal cells (fibroblasts), and in the blood vessels. TGF-beta 1 expression was determined by evaluating 500 cells in the odontoblastic and subodontoblastic layers and 500 fibroblasts in the stroma for each specimen, and counting the number of positive cells. The number of the positive vessels was evaluated in 10 high power fields (HPF). In almost all cases, the cellular positivity was cytoplasmatic. Statistical analysis was performed using Mann-Whitney U- and Student's t-tests. RESULTS: A higher expression of TGF-beta 1 was found in the odontoblastic-subodontoblastic layer of the irreversible pulpitis specimens; this difference was statistically significant (P = 0.0002). No statistically significant difference was observed between the two groups in TGF-beta 1 expression in the stromal cells (P = 0.54) or in the vascular component (P = 0.94). CONCLUSIONS: The higher and statistically significant expression of TGF-beta 1 found in the odontoblastic-subodontoblastic layer of irreversible pulpitis specimens may indicate a role for TGF-beta 1 in the dentinal repair processes after pulp inflammation.

Adolescent↗
PubMed2004

Expression of transforming growth factor-beta 1 (TGF-beta 1) in odontogenic cysts.

AIM: To evaluate the positivity to transforming growth factor-beta 1 (TGF-beta 1) in different types of odontogenic cysts. METHODOLOGY: A total of 30 radicular cysts (RCs), 27 follicular cysts (FCs) and 28 odontogenic keratocysts (OKCs) were evaluated for immunohistochemical analysis of TGF-beta 1. TGF-beta 1 was evaluated in blood vessels, stromal cells (fibroblasts) and pluristratified squamous epithelium. TGF-beta 1 expression was determined by evaluating the number of positive elements. TGF-beta 1 expression was determined by evaluating 1000 cells in the pluristratified squamous epithelium (500 in the basal and parabasal layers, and 500 in the superficial layer) and 500 cells (the fibroblasts in the stroma) for each specimen, and counting the number of positive cells. The number of positive vessels was evaluated in 10 high power fields (HPF). The Chi-square test was used to evaluate differences between the two groups (RC + FC and OKC). A P-value <0.05 was considered to indicate statistical significance. RESULTS: A higher and statistically significant positivity was found in the basal-suprabasal epithelial layers (P=0.0011), superficial epithelium (P=0.053) and stromal cells (P=0.0002) of orthokeratotic and parakeratotic OKC as compared with RC and FC. CONCLUSIONS: These differences suggest that control of the cell cycle may be abnormal in orthokeratotic OKCs. These OKCs may have an intrinsic growth potential not present in other cyst types.

Cell Count↗
PubMed2004

P-cadherin expression predicts clinical outcome in oral squamous cell carcinomas.

P-cadherin, a transmembrane molecule similar to E-cadherin involved in the cell-cell adhesion, and catenins form complexes between its cytoplasmic domain and the cytoskeleton. Five cell lines, 108 specimens of oral squamous cell carcinomas (OSCC), 9 metastasis and 10 of normal oral mucosa were examined to evaluate P-cadherin expression and cellular localization by immunohistochemistry and western-blotting. In normal oral mucosa there was a membranous expression only in basal and parabasal layers. 91 cases (84%) showed membranous/cytoplasmic positivity, whereas 17 cases (16%) were negative. In particular, while well-differentiated carcinomas showed P-cadherin upregulation, the protein was homogeneously hypo- or unexpressed in low-differentiated carcinomas. There was a statistically significant correlation between P-cadherin expression and tumour grading: G3 tumours had a lower score than G1-G2 tumours (P<0.05). When analysed for prognostic significance, patients with no P-cadherin expression (score 0) had poorer overall and diseases-free survival rates than the P-cadherin-expressing group (score 1) (P=0.0463 and P=0.0471, respectively). Western blotting analysis of cell lines and tissue samples confirmed immunohistochemical findings. When cell staining pattern of positive cases was examined, 52 cases showed a prevalent membranous pattern, while 39 had a prevalent cytoplasmic pattern. Cases with prevalent cytoplasmic staining showed high rates of lymph node metastases (P>0.05), and regional relapse (P <0.05) and poorer survival rates than the group with prevalent membranous expression (P<0.0001). An absent P-cadherin expression could constitute a hallmark of aggressive biological behaviour in oral squamous cell carcinoma.

Adult↗
PubMed2003

Titanium-cell interaction: analysis of gene expression profiling.

Titanium and its alloys are used worldwide in surgery. Dental implants, screws and plates, prostheses, and surgical instruments are made with titanium-based metals. The favorable characteristics that make this material desirable for implantation are (a) mechanical proprieties and (b) biocompatibility. The latter has been demonstrated by in vivo studies with animal models and clinical trials over a 40-year period. However, the exact effect of titanium on cells is still not well characterized. Expression profiling by DNA microarray is a new molecular technology that allows the analysis of gene expression in a cell system. Several genes whose expression was significantly up- or downregulated in an osteoblast-like cell line (MG-63) on titanium were identified with the use of DNA microarrays containing 19,200 genes. The differentially expressed genes are associated with a broad range of functional activities, including apoptosis, vesicular transport, and structural function. It was also possible to detect some genes whose function is unknown. The data reported are, to the author's knowledge, the first genetic portrait of titanium-cell interaction. They may help to provide a better understanding of the molecular mechanisms of titanium biocompatibility and serve as a model for studying the biocompatibility of other materials.

Animals↗
PubMed2003

Genetic portrait of malignant granular cell odontogenic tumour.

Odontogenic tumours are rare neoplasms whose classification is sometime controversial. Among these entities, granular cell odontogenic tumour (GCOT) is extremely rare and usually has a benign clinical behaviour. While the histogenesis of GCOT remains to be clarified, we documented the existence of a malignant counterpart of this neoplasm and proposed the name of malignant GCOT. Expression profiling by cDNA microarrays is a molecular technology that enables a global gene expression analysis. By using cDNA microarrays, we identified in malignant GCOT several genes with significantly differentially regulated genes when compared to non neoplastic tissues. These cancer specific genes include a range of functional activities: (1) transcription, (2) signaling transduction, (3) cell-cycle regulation, (4) apoptosis, (5) differentiation and (6) angiogenesis. In conclusion, we show that cDNA microarrays is a useful approach to investigate the biology of tumours. Moreover, this technology might lead to identification of gene targets for cancer therapy and to molecular classification of odontogenic tumours.

Adult↗
PubMed2003

Nerve growth factor beta(NGF beta) delivery via a collagen/hydroxyapatite (Col/HAp) composite and its effects on new bone ingrowth.

In craniofacial surgery, bone is needed to augment misshapen areas and to fill gaps during repair of congenital anomalies and injuries resulting into bone deficiencies. Examples of conditions requiring bone tissue include missing alveolar bone in cleft palates, bony nasal pyramid defects following removal of fistulous tracts or cysts and defects following removal of sinus and mandibular tumors. Moreover, maxillofacial neurosensory deficiencies may be caused by various surgical procedures, such as tooth extraction, osteotomies, pre-prosthetic procedures, excision of tumors or cysts, surgery of TMJ, and surgical treatment of fractures and cleft lip/palate. Therefore, a tissue engineering approach to craniofacial surgery has a crucial importance: the use of various composites with osteoconductive ceramics, polymers, bioactive factors, cells, or a combination of them, offers the possibility of rapid tissue regeneration and integration with the host tissue. In this study, a composite consisting of two well-known biomaterials, collagen/hydroxyapatite (Col/HAp), was used as a drug delivery device for neurotrophin - nerve growth factor beta (NGF beta). This delivery device, enriched with neurogenic-osteogenic factor, was analyzed in vitro and in vivo. It was implanted into calvaria defects of 20 Wistar rats, weighing 200-250 g. Implants were left in place for different periods of time. Controls were as follows: (a) contralateral defect without any implant; and (b) contralateral defect implanted with composite without NGF factor. The rats were euthanized after 30 days, and the implant sites and explants were examined clinically, histologically, SEM and histomorphometrically. Our results evidenced stimulation of periosteal and endocortical woven and lamellar bone formation, with increases in bone mass and decreases in bone marrow. We found that NGF enhanced the remodeling activity in the intracortical region, and induced an increase in the intracortical cavity number and area by the end of the study. In vitro results were in line with in vivo ones. We believe that the composite proposed in this study has considerable advantages in tissue engineering and is very suitable as a biomaterial for the filling of irregular defects in maxillo-facial surgery. Two areas of clinical research will be impacted by this system. The first is pharmaceutical research on drug delivery and high-throughput screening of neurotrophic-osteogenic compounds. Transplantation research is the second area that will benefit from the system.

Journal Article↗
PubMed2003

Genetic expression profiling of six odontogenic tumors.

Odontogenic tumors are rare neoplasms arising from the odontogenic apparatus. We aimed to identify molecular characteristics associated with odontogenic tumorigenesis and malignancy. To this end, we investigated the expression level of human genes by using, for the first time in odontogenic tumors, the technique of expression profiling. Gene expression alterations common to all six odontogenic tumors were identified by the use of cDNA microarrays containing 19,000 human cDNAs. Statistical analysis on a subset of 4974 cDNAs present in the biopsies identified 506 distinct genes associated with the tumors (p-value < 0.01). Gene ontology analysis of the cellular processes which were differentially regulated in odontogenic tumors was accomplished by the use of a subset of 1409 annotated genes. Finally, 43 cDNAs differentiated the three malignant odontogenic tumors (ameloblastic carcinoma, clear cell odontogenic tumor, granular cell odontogenic tumor) from the three benign ameloblastoma biopsies (p < 0.01). The identified genes might help us better classify borderline odontogenic tumors.

Ameloblastoma↗
PubMed2002

Warthin's tumour: a study of 78 cases with emphasis on bilaterality, multifocality and association with other malignancies.

The authors reviewed the clinical records and the histopathological preparations of 78 cases of Warthin's tumours (WTs), treated at the Department of Dental Sciences, Centre for the Study of Oral Tumours, of the University of Bari. All the surgical specimens had been fixed in neutral buffered formalin, sampled according to the step-serial, whole-specimen sectioning technique, embedded in paraffin and stained with haematoxylin-eosin, periodic acid Schiff and Gomori's reticulin. The results showed that Warthin's tumours characteristically affect the parotid gland, and most frequently arise in adults (mean age=57 years) and in males (95%). Multiple tumours were detected in 16 cases (20.5%), and five of these were bilateral (6.5%). One of the multifocal tumours involved an intra-parotideal lymph node and the laryngeal piriform sinus. In addition, 13 cases (16.6%) were associated with other malignancies. These data indicate that multiple (synchronous or metachronous) WTs may occur more frequently than previously reported. The high rate of multiple WTs detected in the current study may result from extensive and accurate sampling of these neoplasms for histopathological evaluation. Consequently, complete preoperative work-up of patients harbouring parotideal tumours consistent with or suspicious for WT is necessary. The work-up should include CT scans and/or magnetic resonance imaging of both parotid glands, to exclude the occurrence of multiple tumours, which may be clinically undetectable. Also, fine needle aspiration biopsy may be an accurate tool for excluding malignant neoplasms and for better planning subsequent surgical procedures. These usually consist in (bilateral) superficial parotidectomy and should be followed by long term follow up of the patients, in view of possible metachronous WTs, even after prolonged time intervals.

Adenolymphoma↗
PubMed2002

Sebaceous adenoma of the cheek.

Sebaceous adenoma is a tumour only rarely located in the oral cavity. Less than 10 cases have been reported. Sebaceous adenoma represents 0.5-0.7% of all monomorphic adenomas. Sebaceous adenoma is mainly constituted by two types of cells, undifferentiated peripheral basaloid cells and cells showing different degrees of sebaceous differentiation located in the center of the lesion. The differential diagnosis must be made with sebaceous hyperplasia. Sebaceous adenomas are benign, and they do not recur after a conservative excision.

Adenoma↗
PubMed2002

p120(cat) Delocalization in cell lines of oral cancer.

UNLABELLED: p120(cat) is a novel component of the catenin family, a cytoplasmic molecule closely associated with the cell-cell adhesion molecule E (epithelial)-cadherin, by forming complexes between the cytoplasmic domain of E-cadherin and the cytoskeleton. Recent studies suppose a role for this molecule in human cancers and to date none report its expression in oral squamous cell carcinomas (SCCs). The goal of this study was to evaluate the role of this protein in the oral carcinogenetic process. A linked streptavidin-biotin-alkaline phosphatase technique was used to examine the immunoreactivity and cellular localisation of p120(cat) in five oral epithelial cell lines (NCTC 2544, normal and immortalized keratinocytes; KB, a poorly differentiated SCC cell line; OSC 20, a well differentiated oral SCC cell line; CAL 33 and CAL 27, moderately differentiated oral SCC cell lines) and 10 normal oral epithelium biopsies. RESULTS: As already reported for E-cadherin, beta- and gamma-catenin, p120 expression showed a homogeneous membranous localization in normal oral specimens. The intensity of staining for p120 progressively increased from basal and parabasal layers toward the intermediate spinous layer. No staining for p120 was observed in the upper layer. NCTC showed a membranous positivity. OSC 20, CAL 33 and CAL 27 showed a membranous positivity, even if polarized to cell-cell adhesion sites, in 40-50% of cells. OSC 20, CAL 33 and CAL 27 cells showed also a cytoplasmic delocalization. All positive KB cells showed a prevalent cytoplasmic staining and 10% of these cells showed a nuclear delocalization. In cancer cells, p120 showed an inverse relationship with the degree of differentiation for a progressive displacement of the signal toward the cytoplasm or nucleus in dedifferentiated cells. In conclusions, this nuclear delocalization for p120 could suppose its potential involvement in signalling and cancer transformation.

Carcinoma, Squamous Cell↗
PubMed2002

Clear cell odontogenic carcinoma.

Clear cell tumours, in the head and neck region, are usually derived from salivary or odontogenic tissues, or may be metastatic. A few clear cells may be present in odontogenic cysts, while, odontogenic neoplasms composed predominantly of clear cells are quite rare. They include calcifying epithelial odontogenic tumours (CEOT), ameloblastoma and odontogenic carcinoma. Clear cell odontogenic tumour (CCOT) has been classified in the last WHO classification as a benign tumour, but it is now recognized as a more sinister lesion and current opinion is that CCOT should be designated as a carcinoma. These tumours are characterized by aggressive growth, recurrences, and metastatic disease. A recent review of the literature has yielded 30 cases of tumours with similar characteristics. These tumours have a peak incidence in the 5th-7th decades, with a female predilection. The anterior portions of the jaws, especially the mandible, are most frequently affected. The aggressive potential of these neoplasms is well documented by the extensive invasion of adjacent tissues, multiple recurrences and regional or distant metastases.

Adenocarcinoma, Clear Cell↗
PubMed2001

Osteolipoma of the tongue.

Lipomas are common, benign tumours located in any part of the body in which fat is normally present. Some variants of lipoma have been described according to the type of tissue present. A rare variant consists of a lipoma with osseous or cartilaginous metaplasia. These lesions have been called chondrolipoma, osteolipoma, lipoma with chondroid or osseous metaplasia, lipoma with cartilaginous or osseous change, or ossifying lipoma. We present the case of an osteolipoma of the tongue in a 49-year-old female who was referred for a painless mass on the left lateral margin of the tongue, and present for about 8 years. Osteolipomas have been reported in middle-aged or elderly patients with a very long clinical history. These tumours tend to be large and to arise from the deep soft or subcutaneous tissues. The cartilage and bone is probably produced by metaplasia of fibroblasts in chondroblasts or osteoblasts. These lesions are benign and do not recur.

Diagnosis, Differential↗