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Cette étude décrit l'expression immunohistochimique de Pan-cadherin et E-cadherin de biopsies mises sous paraffine d'une muqueuse buccale normale (palais, surface dorsale de la tangue, gencive attachée et muqueuse buccale) ainsi que de diverses lésions (lichen planus, pemphigus vulgaris, carcinome in situ, carcinome de cellule squameuse, sarcome de Kaposi et kyste dentaire). La distribution, la localisation et l'intensité des taches apparaissant ont également été évaluées. Les réactions de taches positives, observées avec les deux anticorps sur toutes les sections de tissus normaux, étaient généralement limitées a la couche spinosum; des réactions impliquaient aussi les fibroblastes et les cellules endothéliales dans la lamina propria. Certaines sections de lichen planus, pemphigus vulgaris et kyste dentaire portaient des modeles de taches semblables, Les Cadherins et E-Cadherins étaient limités aux couches épithéliales supérieures et montraient en général une intensité des taches restreinte dans le carcinome in situ et dans le carcinome des cellules squameuses. Le sarcome de Kaposi montrait une faible tache de l'épithélium et aucune réaction de la part des fibroblastes et des cellules endothéliales. Nos observations confirment les données précédentes et constituent un examen supplémentaire pour la biochimie des lésions orales spécifiques.

Toe authors carried out a study on the correlations between TNF-a and fibroblasts. The purpose was to determine the capacity of TNF-a to induce a collagen production in human gingival fibroblasts "jn culture".The cultures treated with TNF-a were obtained from fibroblasts isolated from pathological human gingives.Collagen production indexes used were: -(3H)Proline incorporation - Protein synthesis - DNA synthesis Deterrninations on the cultures were canied out after a short/long treatment with TNF-a against controls on cultures not treated with TNF-a. The results obtained clearly showed the positive inductive action on collagen synthesis provoked by TNF-a in gingival fibroblasts. Furthermore this action

Biochemical variations of adenine and pyridine compounds in human gingival grafts during the period between excision and implantation have been studied. These groups of compounds are considered as «indicators» of the metabolic and energetic status of the living cells. Adenylic compounds such as ATP, ADP and AMP are involved in numerous metabolic processes as «modulators» of allosteric enzymes.NAD+ and NADP+ are involved in the carbohydrate metabolism as co-factors of many reactions of oxydoreduction. The exposure to air of the gingival tissue induces modifications in the energy state of the cells as well as in the ox-reox system. No variation is detectable in the intermediates of the pyridine compounds cycle., Dans des gencives humaines prélevées pour des greffes, ont été étudiées, à certains intervalles de temps entre le prélèvement et la greffe, les variations biochimiques des composés adényliques et pyridiniques, qui sont les «indicateurs» des conditions énergétiques et métaboliques du tissu. Des composés comme l’ATP, l’ADP et l’AMP participent à de nombreux processus métaboliques comme «modulateurs» des enzymes allostériques. NAD+ et NADP + participent au métabolisme des carbohydrates comme co-facteurs de nombreuses réactions d’oxydoréduction. Une brève exposition de la gencive à l’air provoque des changements dans le métabolisme des cellules et du système d’oxydoréduction. Il n’y a pas de variation notable dans les composés intermédiaires du cycle pyridinique.

The major goal endodontic therapy has been achieved by condensing filling materials into the root canal. It’s not uncommon to find excess material into the periapical tissue. It therefore becomes obligatory to use fillings materials that have acceptable biocompatibility.The purpose of this investigation was to obtain a «toxicity profile» of some endodontics materials and to compare our observations to results present in literature.The gutta-percha and five endodontic filling cements were tested «in vivo» and «in vitro».The in vivo biocompatibility involved the placement of the test material in 10 mm. Teflon tubes with an outer diameter of 1.3 mm which were implanted subcutaneously into rats. The implants were left in situ for periods of 30 and 90 days. The «hemolysis test» is designed for «in vitro» evaluations.The istological examination showed different intensity and extent cellular responses. In some cases severe infiltration of inflammatory cell and areas with necrotis were seen.At conclusion, the endodontics material evaluated showed slight, moderate and severe reactions; therefore a different pattern in tissue response., Dans le domaine odontologique, ainsi que dans les autres branches de la médecine, l’exigence d’améliorer constamment la biocompatibilité des matériaux utilisés comme thérapeutique, surtout quand ces matériaux sont destinés à «cohabiter» longtemps avec l’organisme, est de plus en plus ressentie.Dans le cadre d’un vaste programme de recherche, les auteurs se sont proposé d’évaluer la biocompatibilité réelle de quelques matériaux endodontiques choisis parmi les plus courants en Italie: c’est dans ce but qu’ont été effectués des tests «in vitro» (test de l’émolyse d’hématies de lapin) et «in vivo» (selon la technique de Safavi et al. qui prévoit l’implantation du matériel à tester dans le tissu sous-cutané du rat).Les résultats des tests ont démontré la variabilité du grade de biocompatibilité des matériaux soumis à l’expérimentation. Certains matériaux n’ont provoqué en effet qu’une légère réaction des tissus, d’autres ont déterminé la formation d’importants infiltrats de cellules inflammatoires, de macrophages, de cellules géantes de corps étranger et de colliquation nécrotique tissulaire.

Five enamel pearls were examined by Scanning Electron Microscope. Some external pearls presented a bare enamel surface, others were covered by a thin layer of cementum.The enamel pearls showed irregular dystrofic enamel surface or a thin layer without structure, rows of irregular Tome’s processes pits, enamel caps and focal holes. Some enamel pearls revealed little areas of enamel surface resorption like-resorbing lacunae with, in some cases, areas of tissue repair., La perle d’émail est une masse circulaire de matériel calcifié qui apparait le plus souvent dans la bifurcation des molaires et est attachée à la surface externe de la dent. Elle peut aussi être interne mais nous en savons très peu à ce sujet à cause du manque de publications. Cinq perles externes ont été observées au microscope électronique à balayage.Tandis que certaines perles externes présentent une surface à nu, d’autres sont recouvertes d’une fine couche de cément qui les protège. La surface de la perle d’émail présente des zones irrégulières d’hypominéralisation ou une fine couche sans structure, des rangées de petits trous irréguliers des processus de Tome et des trous focaux et des cratères.

The results of our recent microscopy studies clearly have demonstrated the constant presence of numerous metachromatic cells in healthy human gingival connective tissue. Despite the great number of studies on mast cell population in many human organs (lung, skin, uterus, and bowel), at the present time few are the studies regarding the morphostructural aspects of mast cells in the human gingiva. The aim of this study was to assess by transmission electron microscopy the presence of mast cells in the healthy human gingiva and to characterize the ultrastructural aspects of mast cells populations. 30 specimens of human gingival tissue were collected from 30 patients with informed consent. The samples were prepared for T.E.M. examination. In all the ultrathin sections observed we detected numerous and ubiquitarious mast cells. These exhibited several morphological types of cytoplasmic granules with characteristic subgranular architectural variety in shape and density. This allowed us to divide mast cells into two groups: cells with granules consisted of compact coiled scrolls, fine granular material and lattice - grating configuration, and cells containing granules with discrete scrolls formed by more concentric lamellae and particulate structure. The two ultrastructural aspects observed correspond to McTC and McT of the international literature. Therefore in the human gingival connective tissue, like in other organs, two types of mast cells are clearly present. Surprisingly, the human gingival tissue shows, like the lung, McT as the prevailing subpopulation, in contrast to the skin, uterus and gastrointestinal submucosa where McTC prevail., Dans le cadre d’une étude sur la population cellulaire du tissu conjonctif gingival humain nous avons constaté, en microscopie optique, la présence constante de nombreuses cellules metachromatiques. Pour définir la nature de telles cellules et pour en déterminer les aspects ultra-structuraux, nous avons étudié au microscope électronique à transmission 30 biopsies du tissu gingival humain, cliniquement sain. Dans tous les échantillons examinés nous avons observé de nombreux mastocytes dont le contenu granulaire nous est apparu caractérisé par un aspect « à particules » et « en rouleaux » ou bien, dans d’autres éléments cellulaires, par un aspect «en grillage». Les deux aspects ultrastructuraux décrits nous permettent de distinguer les mastocytes gingivaux en deux sous-populations, différentes comme l’ont confirmé plusieurs auteurs, selon la localisation anatomique, selon la structure intérieure et le contenu enzymatique des granules, et, enfin, selon la réaction à des substances sécrétagogues.

Five enamel pearls were examined by Scanning Electron Microscope. Some external pearls presented a bare enamel surface, others were covered by a thin layer of cementum.The enamel pearls showed irregular dystrofic enamel surface or a thin layer without structure, rows of irregular Tome’s processes pits, enamel caps and focal holes. Some enamel pearls revealed little areas of enamel surface resorption like-resorbing lacunae with, in some cases, areas of tissue repair. La perle d’émail est une masse circulaire de matériel calcifié qui apparait le plus souvent dans la bifurcation des molaires et est attachée à la surface externe de la dent. Elle peut aussi être interne mais nous en savons très peu à ce sujet à cause du manque de publications. Cinq perles externes ont été observées au microscope électronique à balayage.Tandis que certaines perles externes présentent une surface à nu, d’autres sont recouvertes d’une fine couche de cément qui les protège. La surface de la perle d’émail présente des zones irrégulières d’hypominéralisation ou une fine couche sans structure, des rangées de petits trous irréguliers des processus de Tome et des trous focaux et des cratères.

La quarta edizione del terzo volume del Trattato di Anatomia Umana vede un'estesa revisione sia della parte iconografica che del testo con (i) l'adeguamento della terminologia all'ultima edizione della "Terminologia Anatomica", (ii) l'analisi del particolare anatomico incentrata sulla sua diretta attinenza clinica o fisiologica, (iii) l'introduzione di box per evidenziare importanti correlati morfofunzionali e (iv) l'inserimento di numerosi correlati clinici

In this work it is discussed whether and how Kretchmer's psychopathological reflections about sensitive delusion of reference can offer a relevant interpretative key for clinicians who face cases of acute persecutory psychosis. It is argued the utility and topicality of those psychopathological concepts that aren't commonly investigated, especially in the evaluation and management of onset paranoid psychosis in an emergency ward.We provide clinical vignettes of two young patients, admitted in the emergency psychiatry ward, who represent a concrete example of the dynamic-affective comprehension of delusional elaboration, through its embodiment in the individual biographical development.An interpretative key, based on this specific conceptual frame, seems to provide an integrated intervention tool that aims both to a causal comprehension and demolition of the delusional solution in onset psychotic cases.The rediscovery of classical psychopathological concepts appears to be a necessary process, especially in the clinical management of onset psychotic disorders. Further and more accurate researches are, in any case, needed.

During embryonic and foetal development, the masseter is formed from two successive generations of muscle fibers in a manner which is very similar to that which has been previously described for other skeletal muscles. This phenotypeis characterised by the persisten ce of ontogenic myosin isoforms ( embryonic and foetal myosin heavy chains, embryonic light chain) and by the presence of two distinct populations of fibers : small diameter fibers which coexpress theembryonic, foetal and fast isoforms of the myosin heavy chains but never express the slow isoform; large diameter fibers which express the slow myosin heavy chain either exclusively or in variable associations with the other isoforms.These characteristics of the human masseter muscle probably correspond not only to its embryological origin and its special innervation, but also to the functional constraints to which it is submitted after birth., Le développement du masséter s'effectue pendaQt la vie embryo-fa:tale en deux générations de fibres suivant un schéma tres comparable a la plupart des a u tres muscles de l 'organisme. Apres la naissance, un phénotype particulier se caractérise par l'expression persistante d'isoformes ontogéniques de la myosine (isoformes embryonnaire et fa:tale des chaines lourdes, isoforme embryonnaire des chaines légeres) et par l'individualisation de deux populations de fibres: de petite taille coexprimant les isoformes embryonnaire, fa:tale et rapide des chaines lourdes de la myosine mais n'exprimant pas l'isoforme lente; de grande taille exprimant l'isoforme lente des chaines lourdes de la myosine seule ou diversement associée aux autres isoformes.II est vraisemblable que les spécificités du masséter humain traduisent non seulement son origine embryologique et son innervation particuliere mais également les contraintes fonctionnelles qu'il subit apres la naissance.

span style="font-size: 12px; line-height: 14px" class="Apple-style-span"Dental amalgam (AMG) is the most diffused dental filling material. Since it is constituted for at least 40-45% of Hg, many questions have raised about its safe use. Hg particles from dental amalgam dissolve in saliva and, being ingested, they reach the blood stream through the intestinal mucosa. It has been demonstrated that amalgam fillings continuously release Hg vapour and that there is detectable Hg in expired and inspired air of amalgam owners. It is not yet fully accepted that AMG fillings represent the principal source of Hg for man and the aim of this study was to evaluate if the mercury level in saliva: 1) was higher within people bearing dental amalgam restorations than in people with no restorations; 2) was different between males or females; 3) increased in relation to the surface of amalgam restorations. The results showed a correlation between number of fillings and salivary Hg, between amalgam surface and salivary Hg. The Authors could finally assert that AMG fillings represented the principal source of salivary Hg in the subjects studied./span

span style="font-size: 12px; line-height: 14px" class="Apple-style-span"In order to evaluate the influence of mercury (Hg) levels on antioxidant power in human plasma, 26 healthy people were evaluated by a dentist and their plasma analyzed for Hg content by atomic absorption and total antioxidant activity (TAA) by FRAP method. Hg plasma concentration correlated with number of amalgam restorations, suggesting that Hg released from fillings is a source of Hg in non-occupational exposed people. Fish consumption, in fact, showed no influence on Hg plasma levels, perhaps because Italian subjects examined in the present group used low quantity of fish at week or kinds of fish with light contamination. TAA negatively correlated with Hg plasma revealing a pro-oxidant role of Hg released from amalgam fillings./span

span style="font-size: 12px; line-height: 14px" class="Apple-style-span"Meckel's cartilage plays an important role in the topographical organisation and in the differentiation of the facial structure during the embryonal and even much later during the foetal period. Our observations on serial sections carried out in two human foetuses aged 12 and 16 weeks indicate that the two dorsal (tympanic) and ventral (mandibular) branches of Meckel's cartilage are perfectly defined at 16 weeks. In the dorsal branch, the primordia of the incus and of head of the malleus are still composed on non-ossified cartilage. In the ventral branch, it is also possible to describe at 16 weeks three posterior, medial and anterior parts which are composed of cartilage. The initiating role played by the ventral part of Meckel's cartilage on the ossification of the mandible leads during the embryonal period to the formation of the mandibular primary growth center, which is therefore clearly defined in our first stage at 12 weeks. The partial fibrous evolution and the regression of the major part of the ventral branch of Meckel's cartilage only start after 16 weeks of intrauterine life./span