Biomedical subjects

N Staffolani

Publications and source records attributed to N Staffolani.

At least 19 recordsLinked to original sources

PubMed1998

PAF levels in saliva are regulated by inflammatory cells.

Platelet activating factor (PAF), a powerful inflammatory phospholipid mediator, has been detected in normal human saliva and found to be increased in periodontitis. The cellular source of PAF in saliva is controversial although several data suggest an origin related to the presence of inflammatory cells. PAF levels in biological fluids are regulated by PAF-producing cells and by the PAF-degrading acetylhydrolase. Although in normal human saliva acetylhydrolase activity is very low, no information is available on the levels of this enzyme in inflammatory conditions of the mouth. The aim of our study was to assess the contribution of inflammatory cells to the levels of PAF in saliva in normal subjects and in patients with periodontitis. PAF was measured by radioimmunoassay (RIA) in mixed uncentrifuged saliva and in cell-free saliva from healthy subjects, before and after tooth brushing, and in patients with periodontitis. In healthy subjects PAF levels were significantly higher in whole saliva than in centifuged saliva (1.51 +/- 0.22 vs. 0.92 +/- 0.04 ng/ml, p < 0.0039). A significant increase in the amount of PAF was detected in whole saliva, but not in centifuged saliva, 2 h after tooth brushing. In patients with periodontitis PAF levels were not different from those of healthy individuals when using centrifuged saliva but were significantly higher when using whole, uncentrifuged saliva. Exogenous radiolabelled PAF was degraded much more rapidly by the saliva of periodontitis patients than by that of normal subjects. In conclusion, our study shows that inflammatory cells regulate the levels of PAF in saliva contributing to its production and degradation. The differential degradation of PAF in normal and inflammatory saliva highlights the absolute need of a series of methodological precautions when performing studies on salivary PAF.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗

PubMed1997

Phenotype expression of human bone cells cultured on implant substrates.

Bone cells derived from the human jaw were cultured on titanium, titanium coated with hydroxyapatite (THA) or with plasma spray (TPS) to study the behaviour of the cells anchored to implant substrates. Bone cells were cultured in MEM with the addition of [3H]-thymidine to evaluate cellular proliferation, and [3H]-glucosamine to evaluate GAG synthesis and accumulation in the extra-cellular matrix (ECM). Moreover, to study the degradation of GAG bone cells were cultured in the presence of NH4Cl, an amine known to inhibit lysosomal activity. Our results show that TPS is the substrate that favours both cellular proliferation and the accumulation of GAG in the ECM.

Ammonium Chloride↗

PubMed1997

Phenotype expression of gingival fibroblasts cultured on membranes used in guided tissue regeneration.

Human gingival fibroblasts were cultured in vitro using as substrates an extracellular matrix (matrix) and polytetrafluoride (PTFE) membranes, which are used in guided tissue regeneration. To test the degree of biocompatibility of these membranes, the cellular proliferation and the accumulation of extracellular matrix (ECM) macromolecules were considered as parameters. The fibroblasts were cultured in vitro for 24 and 48 hours without serum on plastic, matrix, and PTFE membranes in the presence of 3H-thymidine, 3H-glucosamine, and 3H-proline to study the neo-synthesis of DNA, glycosaminoglycans (GAG), and collagen proteins, respectively. Studies on cell proliferation showed that fibroblasts grown on matrix membrane significantly increased 3H-thymidine incorporation, while fibroblasts grown on PTFE membrane decreased 3H-thymidine incorporation, compared to plastic used as a control. Moreover, the PTFE membrane induced a marked decrease of collagen and GAG accumulation both in the cellular and extracellular pool, while the matrix membrane provoked a decrease of the two macromolecules in the cellular pool and an increase in the extracellular one, compared to the control. The data we obtained demonstrate that matrix membranes are the most suitable to stimulate both cellular proliferation and ECM macromolecule accumulation.

Adult↗

PubMed1997

[Etiopathogenic hypotheses on dental ankylosis].

The authors review the literature about the different etiopathogenetic hypotheses of tooth ankylosis. They classified the ankylosis in three big groups: traumatic ankylosis due to direct and indirect injuries to the tooth, iatrogenic ankylosis due to unadvised maneuvers made by the dentist, and atraumatic ankylosis. The last is the most important group caused by metabolic problems and with family characteristics. Furthermore they underline the important role played by GAG and corresponding lytic enzymes in the development of atraumatic ankylosis. They described, the therapeutical procedures to be used in the different cases. The clinical cases presented are representative of the different therapeutical approaches.

Ankylosis↗

PubMed1996

Metal substrates influence the release of glycosaminoglycan and transforming growth factor beta by human bone cells.

Bone cells derived from human jaw were isolated from explants and grown in vitro. Subcultures were cultured on plastic (control) and metal substrates for 24 and 48 hours in medium containing 3H-glucosamine and labeled glycosaminoglycan (GAG) accumulation was measured. In bone cells cultured on metal substrates there was an evident reduction in the synthesis and secretion of radiolabeled macromolecules compared to bone cells cultured on plastic. Moreover, the accumulation of single GAG classes was specific for each substrate tested. The results showed that titanium was the only metal substrate studied in which the percentage of individual GAG classes remained the same as control cultures. GAG reduction was due to a decreased synthesis and not to an increased degradation as shown by the decrement of exoglycosidase activity. The metals also reduced the activity of transforming growth factor beta (TGF beta), measured using interleukin-1 assay method, a factor involved in the various phases of bone remodeling; in this case, too, cells grown on titanium showed the highest TGF beta activity compared to the other metal substrates studied. The results indicate that the substrate to which the cells adhere do exhibit specific differences in GAG composition and TGF beta activity. The differences observed may be important during in vivo events such as guided tissue regeneration and bone deposition.

Acetylglucosaminidase↗

PubMed1996

[The measurement of PAF (platelet activating factor) in human saliva: standardization of the method].

The evaluation of the salivary PAF has possible by using the radio immuno assay method (RIA). We wanted to study the presence of such substance in the saliva under physiological conditions and particularly in relation to possible existence of a circadian rhythm or periodical oscillations. The work has been developed in two phases. In the first one we evaluated the daily salivary PAF amount while in the second phase of the study we verified the existence of a possible circadian rhythm. The results encouraged us to extend the study to the typical, different physiological aspects of such phospholipid having as objective the control of the salivary PAF amount in pathological conditions.

Circadian Rhythm↗

PubMed1995

[Maxillofacial-dental anomalies in cleidocranial dysostosis].

The authors evaluated the dento-maxillofacial anomalies in cleido-cranial dysplasia; the use of a removable orthodontic appliance can solve orthodontic problems particularly the deficiency of anchorage.

Abnormalities, Multiple↗

PubMed1994

[Maxillofacial and dental anomalies in multiple-abnormality syndromes. The clinical and therapeutic aspects in Sotos' syndrome].

The authors describe the maxillo-facial and dental anomalies present in a rare polymalformative syndrome: Sotos' syndrome. After having examined the syndrome and reported a case, they propose a therapeutic approach for the treatment of young handicapped cooperating patients.

Abnormalities, Multiple↗

PubMed1994

[An in-vitro study of the antimicrobial activity of copper and zinc salts on pure and mixed microbial cultures].

The authors evaluated the in vitro antimicrobial activity of some copper and zinc salts. The results showed high antimicrobial activity of copper salts versus S. mutans and versus the bacterial association tested in this study.

Candida albicans↗

PubMed1990

Orthodontic/surgical management of dentofacial disharmonies.

The rationale for orthodontic/surgical management of dentofacial deformities was reviewed for single and double jaw problems. Coordinated interdisciplinary work-ups and treatment modalities can produce predictable results. In well-selected cases, esthetics and functional stability are greatly enhanced by the combined technique.

Adolescent↗

PubMed1990

[The role of tympanometric examination in the orthodontic study of mouth breathers].

The mouth breathing is a multidisciplinary problem; in fact, when the orthodontist finds a patient with altered dento-skeletal growth due to this abnormal mode of breathing, to establish a correct treatment planning, he needs to be supported [correction of comforted] by ear, nose and throat examinations. Among these, the tympanogram, because of its simple execution and of the interesting data obtained, has a very important role in the orthodontic approach of the oral breather.

Acoustic Impedance Tests↗

PubMed1989

[Hormonal receptors in gingival inflammation].

An empiric correlation between the inflamed gingiva and hormonal variations during physiological conditions such as pregnancy and menstrual cycle is already known. The demonstration of specific steroid receptors in human gingiva has suggested a relationship between the ovarian hormones and the dimensional changes of the gingiva. In this work, estrogen and progesterone receptors in healthy and inflamed gingiva have been studied.

Adolescent↗

PubMed1982