Structural and morphometrical study in glandular parenchyma from alcoholic sialosis.

BACKGROUND: The aim of this work was to determine morphometrical changes in lingual, labial and submaxillar salivary glands from alcoholic chronics. METHODS: Five samples of each type of gland were obtained from autopsies of chronic alcoholics and equal number of samples from individuals whose death cause was accidental (controls). Serous acini in von Ebner and submaxillar glands and mucous acini in labial and Blandin-Nühn glands were analysed. In the ductal system, intra and interlobular striated ducts were studied. A digital-image analyser was used to measure different parameters in the acini and ducts. RESULTS: Statistical analysis revealed that lingual and submaxillar salivary glands presented a significant acinar hypertrophy and hyperplasy. These changes were not observed in labial salivary glands. All studied glands showed significant structural modifications in the striated ducts. CONCLUSION: These results indicate that the significant variations together with the histological qualitative pattern could be useful as confident indicators for the differential histopathological diagnosis with other sialosis from different aetiology.

Osteoprotegerin (OPG) and RANKL expression and distribution in developing human craniomandibular joint.

During embryogenesis the bone tissue of craniomandibular joint (CMJ) is formed through two pathways: intramembranous ossification and endochondral ossification. The development process is under the control of regulatory factors. The osteoprotegerin (OPG) and the receptor activator of nuclear factor (NF)-kappaB ligand are key regulators of osteoclastogenesis. The aim of this study is the localization of OPG and RANKL mRNA and protein in the foetal CMJ by immunohistochemistry (IHC) and in situ hybridization (ISH). The main results were: OPG and RANKL mRNA and protein were co-localized in the same cell types; OPG and RANKL were specially immunolocated in osteogenic cells; immunolabeling was often seen in the nucleus and cytoplasm of otherwise negative hypertrophic chondrocytes; IHC and ISH labeling decreased from proliferative to hypertrophic chondrocytes; early osteocytes showed dual protein expression and some of the mature osteocytes were ISH-negative; periosteal osteoclasts and chondroclasts were mostly stained by IHC and variably labeled by ISH; the new bone matrix and trabecular borders showed intense immunolabeling. The co-expression of OPG and RANKL in the same bone cell types confirms their strictly coupled action in the regulation of bone metabolism in the CMJ development and their extracellular presence in the new bone matrix and trabecular borders suggests a local regulatory role.

Estudio estructural y microanalítico de los tejidos duros en molares primarios / A structural and microanalytical study of hard tissues in primary molars

El presente trabajo se realizó con el objeto de corroborar y relacionar los aspectos estructurales de los molares primarios observados con MO y MEB y aplicar las técnicas de histoquímica microanalítica para determinar los patrones cuantitativos de mineralización del esmalte y dentina. Se utilizó un total de 30 molares (1º y 2º) clínicamente sanos, exfoliados. El estudio para microscopía óptica (MO) fue mediante la técnica por desgaste y cortes procesados y metalizados para la electrónica de barrido (MEB). En el esmalte se identificó la zona aprismática periférica, la línea neonatal, abundantes husos, conductillos dentinarios remanentes y microdefectos (laminillas o cracks de morfología y longitud variables). La dentina se caracterizó por la amplitud de los túbulos y escasa o nula dentina intertubular a nivel circumpulpar. El microanálisis con energía dispersiva de rayos X puso de relieve que el índice calcio/fósforo, tanto en esmalte como en dentina, alcanza el valor de 1.7, lo que sugiere que en la configuración de los cristales de apatita existen aniones carbonato. Los hallazgos de frecuentes microdefectos y la presencia de numerosas estructuras sin esmalte (husos y conductillos penetrantes) en la conexión amelodentinaria, especialmente en la porción coronaria oclusal nos advierte de los cuidados o precauciones a tomar en el momento de usar ácidos grabadores. Asimismo, la existencia de patrones de mineralización similares entre elementos primarios y permanentes, permite inferir que la terapéutica odontológica basada en la naturaleza de lamineralización podría aplicarse con idénticas pautas, pero respetando las variaciones estructurales respectivas

Estudio estructural y microanalítico de los tejidos duros en molares primarios / A structural and microanalytical study of hard tissues in primary molars

El presente trabajo se realizó con el objeto de corroborar y relacionar los aspectos estructurales de los molares primarios observados con MO y MEB y aplicar las técnicas de histoquímica microanalítica para determinar los patrones cuantitativos de mineralización del esmalte y dentina. Se utilizó un total de 30 molares (1º y 2º) clínicamente sanos, exfoliados. El estudio para microscopía óptica (MO) fue mediante la técnica por desgaste y cortes procesados y metalizados para la electrónica de barrido (MEB). En el esmalte se identificó la zona aprismática periférica, la líne

Estudio estructural y microanalítico de los tejidos duros en molares primarios / A structural and microanalytical study of hard tissues in primary molars

El presente trabajo se realizó con el objeto de corroborar y relacionar los aspectos estructurales de los molares primarios observados con MO y MEB y aplicar las técnicas de histoquímica microanalítica para determinar los patrones cuantitativos de mineralización del esmalte y dentina. Se utilizó un total de 30 molares (1º y 2º) clínicamente sanos, exfoliados. El estudio para microscopía óptica (MO) fue mediante la técnica por desgaste y cortes procesados y metalizados para la electrónica de barrido (MEB). En el esmalte se identificó la zona aprismática periférica, la línea neonatal, abundantes husos, conductillos dentinarios remanentes y microdefectos (laminillas o cracks de morfología y longitud variables). La dentina se caracterizó por la amplitud de los túbulos y escasa o nula dentina intertubular a nivel circumpulpar. El microanálisis con energía dispersiva de rayos X puso de relieve que el índice calcio/fósforo, tanto en esmalte como en dentina, alcanza el valor de 1.7, lo que sugiere que en la configuración de los cristales de apatita existen aniones carbonato. Los hallazgos de frecuentes microdefectos y la presencia de numerosas estructuras sin esmalte (husos y conductillos penetrantes) en la conexión amelodentinaria, especialmente en la porción coronaria oclusal nos advierte de los cuidados o precauciones a tomar en el momento de usar ácidos grabadores. Asimismo, la existencia de patrones de mineralización similares entre elementos primarios y permanentes, permite inferir que la terapéutica odontológica basada en la naturaleza de lamineralización podría aplicarse con idénticas pautas, pero respetando las variaciones estructurales respectivas (AU)

Nucleolar organizer regions (NORs) evaluation of lingual salivary glands of chronic alcoholics.

BACKGROUND: Chronic alcoholism has been associated with structural and physiological changes in salivary glands. Studies on a variety of pathologies have suggested that variation in number of nucleolar organizer regions (NORs) reveals conditions of cellular activity. The aim of this work was to examine, through the AgNOR technique, changes in number and size of NORs in lingual salivary glands of chronic alcoholics. METHODS: Samples of mucous and serous lingual salivary glands were obtained from tongues from autopsies of individuals whose cause of death was hepatic alcoholic cirrhosis. Lingual organs from individuals whose cause of death was accidental were used as controls. Number and size of the AgNORs and nuclear area, in ductal and acinar cells, were evaluated through a digital image analyzer. RESULTS: Statistical analysis revealed differences (P < or = 0.05) in number of AgNORs in mucous acini and ductal cells. Also, we observed changes in the area of the NORs. CONCLUSION: These results suggest that in alcoholics the activity of glandular cells, mainly in ductal epithelium, could be affected, modifying synthesis, transport and salivary secretions.

Cambios estructurales del complejo articular temporomandibular (CATM) humano en distintas edades gestacionales / Human temporomandibular articular complex structural changes in different gestational ages

Se analizaron los cambios estructurales de los distintos componentes del CATM en fetos humanos de 16, 18, 24 y 37 semanas de gestación, con el propósito de identificar el grado de maduración tisular y asociarlo con su posible capacidad funcional para efectuar los movimientos mandibulares. Se emplearon técnicas histoquímicas de rutina y de inmunomarcación. Los anticuerpos utilizados fueron proteína de neurofilamentos (NE14), vimentina y mioglobina mediante el sistema avidina-biotina, DAB. Las variaciones observadas en las distintas edades gestacionales se encontraron principalmente, a nivel del disco articular y cóndilo mandibular. Entre las 16 y 18 semanas, el disco mostró fibrillas PAS positivas y abundantes fibras argirófilas dispuestas en plexos. Las fibras elásticas fueron escasas y muy delgadas en la zona bilaminar póstero-superior. A las 24 semanas, el CATM mostró un aumento notable en las dimensiones de todos sus componentes. El disco de mayor espesor exibió una proporción más elevada de fibras colágenas y elásticas, mientras que las fibrillas argirófilas organizadas en haces adquirieron una disposición específica. Se identificaron nervios inmunorreactivos con NE14 en la zona anterior y en el espacio laminar póstero-inferior próximo al cóndilo. En los especímenes de mayor edad, los cortes sagitales del disco aislado, mostraron diferentes regiones según el espesor y la disposición de las fibras colágenas. Algunos haces musculares del pterigoideo dispuestos en zig-zag y con apariencia de un estado de semicontracción, no expresaron la mioglobina. A las 24 semanas, los componentes del CATM presentaron, en general, características similares a las observadas en los fetos de término. La maduración de los músculos asociados y de los tejidos articulares, en especial del disco, permite sugerir que los componentes del CATM estarían capacitados para desarrollar actividades de apertura y cierre mandibular a partir de esta etapa prenatal.

Scanning electron microscopy and calcification in amelogenesis imperfecta in anterior and posterior human teeth.

Teeth fragments from members of a family clinically and genetically diagnosed as having amelogenesis imperfecta were studied by scanning electron microscopy and X-ray microprobe analysis to establish the morphological patterns and the quantitative concentration of calcium in the enamel of anterior (canine, incisor) and posterior (premolar and molar) teeth. The prism patterns in the enamel of teeth from both regions were parallel or irregularly decussate, with occasional filamentous prisms accompanied by small, irregularly rounded formations. Prismless enamel showed the R- and P-type patterns. Calcium levels in enamel of amelogenesis imperfecta and control teeth differed significantly between anterior and posterior teeth, indicating that the factors that influence normal mineralization in different regions of the dental arch are not altered in the process of amelogenesis imperfecta.

Mineralization of human premolar occlusal fissures. A quantitative histochemical microanalysis.

The mechanisms of cariogenesis in occlusal fissures remain elusive because of limited information about fissure structure and wall mineralization. The purpose of the present study was to determine the correlation between morphological patterns in occlusal fissures in human premolars and quantitative histochemical patterns of mineralization in the walls of these formations. We used scanning electron microscopy and quantitative X-ray microanalysis with the peak-to-local background ratio method and microcrystalline calcium salts as standards. We distinguished three morphological patterns of fissures in scanning electron microscopic images. The wall of the fissures was less mineralized than the control enamel in all three types of fissures. Because the fissure walls are hypomineralized, we suggest that practicing dentists should take into account the degree of mineralization when they are preparing the fissures for the application of sealant.

A structural and immunocytochemical study of palatine and labial salivary glands from chronic alcoholics.

In the present study we investigated tissue changes in palatine (PG) and labial (LG) minor salivary glands from individuals who had died of alcoholic hepatic cirrhosis, to characterize histopathological parameters of alcoholic sialosis, that may be used for differential diagnosis. Samples obtained from autopsies were processed using cytochemical techniques for mucosubstances and immunocytochemical labelling for cytokeratines, PS 100 and T-cells. Both PG and LG showed dilated excretory ducts with atrophic epithelium, which contained PAS+ metachromatic material and detached cells. Intra and interlobular ductal hyperplasia was present in some areas, mainly in PG. CK expression was heterogeneous in ductal cells, and negative in acinar cells. Most of the acinar cell nuclei were normal, but some of them were atypical in shape and distribution. Myoepithelial cells, serous demilunes and the basal region of the cells of the striated ducts expressed PS 100. In PG, 85% of the mononuclear infiltrates expressed T-cell markers, whereas in LG only 40% of these cells were T-cells. These findings, in addition to other histopathological parameters seen in previous studies, may be used as indicators for differential diagnosis with other gland pathologies.

A structural and immunocytochemical study of palatine and labial salivary glands from chronic alcoholics

In the present study we investigated tissue changes in palatine (PG) and labial (LG) minor salivary glands from individuals who had died of alcoholic hepatic cirrhosis, to characterize histopathological parameters of alcoholic sialosis, that may be used for differential diagnosis. Samples obtained from autopsies were processed using cytochemical techniques for mucosubstances and immunocytochemical labelling for cytokeratines, PS 100 and T-cells. Both PG and LG showed dilated excretory ducts with atrophic epithelium, which contained PAS+ metachromatic material and detached cells. Intra and interlobular ductal hyperplasia was present in some areas, mainly in PG. CK expression was heterogeneous in ductal cells, and negative in acinar cells. Most of the acinar cell nuclei were normal, but some of them were atypical in shape and distribution. Myoepithelial cells, serous demilunes and the basal region of the cells of the striated ducts expressed PS 100. In PG, 85

of the mononuclear infiltrates expressed T-cell markers, whereas in LG only 40

of these cells were T-cells. These findings, in addition to other histopathological parameters seen in previous studies, may be used as indicators for differential diagnosis with other gland pathologies.

A structural and immunocytochemical study of palatine and labial salivary glands from chronic alcoholics.

In the present study we investigated tissue changes in palatine (PG) and labial (LG) minor salivary glands from individuals who had died of alcoholic hepatic cirrhosis, to characterize histopathological parameters of alcoholic sialosis, that may be used for differential diagnosis. Samples obtained from autopsies were processed using cytochemical techniques for mucosubstances and immunocytochemical labelling for cytokeratines, PS 100 and T-cells. Both PG and LG showed dilated excretory ducts with atrophic epithelium, which contained PAS+ metachromatic material and detached cells. Intra and interlobular ductal hyperplasia was present in some areas, mainly in PG. CK expression was heterogeneous in ductal cells, and negative in acinar cells. Most of the acinar cell nuclei were normal, but some of them were atypical in shape and distribution. Myoepithelial cells, serous demilunes and the basal region of the cells of the striated ducts expressed PS 100. In PG, 85

of the mononuclear infiltrates expressed T-cell markers, whereas in LG only 40

of these cells were T-cells. These findings, in addition to other histopathological parameters seen in previous studies, may be used as indicators for differential diagnosis with other gland pathologies.

Histological study of parotid, submaxillary and von Ebner salivary glands in chronic alcoholics.

Samples from parotid, submaxillary, and von Ebner salivary glands of six chronic alcoholic individuals who had died of alcoholic hepatic cirrhosis were analyzed by topographic and histochemical routine stains and marked for cytokeratins; two normal adult individuals were used as control. Modifications in the acinar cells were found, but the most evident changes were observed in the ductal system: enlargement of major ducts, heterogeneous expression of cytokeratins and athrophy in epithelial cells, desquamated cells and stasis of content, and ductal hyperplasia in von Ebner glands. The lymphoplasmocytic infiltration does not represent the typical lymphocytic focus on Sjögren's syndrome or other connective tissue pathologies. Our findings indicate that functional and structural variations are produced both in serous acini and ducts parotid, submaxilar and von Ebner glands affected by alcoholic sialosis.

Histological study of parotid, submaxillary and von Ebner salivary glands in chronic alcoholics

Samples from parotid, submaxillary, and von Ebner salivary glands of six chronic alcoholic individuals who had died of alcoholic hepatic cirrhosis were analyzed by topographic and histochemical routine stains and marked for cytokeratins; two normal adult individuals were used as control. Modifications in the acinar cells were found, but the most evident changes were observed in the ductal system: enlargement of major ducts, heterogeneous expression of cytokeratins and athrophy in epithelial cells, desquamated cells and stasis of content, and ductal hyperplasia in von Ebner glands. The lymphoplasmocytic infiltration does not represent the typical lymphocytic focus on Sj÷gren’s syndrome or other connective tissue pathologies. Our findings indicate that functional and structural variations are produced both in serous acini and ducts parotid, submaxilar and von Ebner glands affected by alcoholic sialosis.

Histological study of parotid, submaxillary and von Ebner salivary glands in chronic alcoholics.

Samples from parotid, submaxillary, and von Ebner salivary glands of six chronic alcoholic individuals who had died of alcoholic hepatic cirrhosis were analyzed by topographic and histochemical routine stains and marked for cytokeratins; two normal adult individuals were used as control. Modifications in the acinar cells were found, but the most evident changes were observed in the ductal system: enlargement of major ducts, heterogeneous expression of cytokeratins and athrophy in epithelial cells, desquamated cells and stasis of content, and ductal hyperplasia in von Ebner glands. The lymphoplasmocytic infiltration does not represent the typical lymphocytic focus on Sj÷grens syndrome or other connective tissue pathologies. Our findings indicate that functional and structural variations are produced both in serous acini and ducts parotid, submaxilar and von Ebner glands affected by alcoholic sialosis.

Electron probe microanalysis of permanent human enamel and dentine. A methodological and quantitative study.

Sample preparation of dental tissues for quantitative electron microprobe analysis has not been critically examined because of the highly mineralized nature of these structures. The present study was designed to establish the most suitable method for the electron probe quantitative determination of calcium in human permanent enamel and dentine while preserving the morphological features. Comparisons of quantitative data obtained with air-drying and freeze-drying methods showed that calcium in enamel was more accurately measured in specimens prepared with cryopreservation and freeze-drying. No significant differences between the methods tested were found in dentine although cryopreservation and freeze-drying yielded less statistical variability. Moreover this approach did not modify morphological features of interest. We recommend this combination of processing techniques for human permanent teeth not only because it was found the most accurate and least variable in determining calcium concentration, but also because of its potential usefulness in studies of alterations in tooth mineralization.

Comparative study of AgNOR and PCNA in experimental carcinogenesis of salivary glands of rats.

Previous studies regarding experimental carcinogenesis demonstrated that submaxillar glands (GSM) submitted to DMBA present cellular modifications of progressive gravity in different periods after eight days of the experiment (J. Dent. Res 59: 1067, 1980). This current work pursues the objective of determining, quantitatively, regions of nucleolar organizations (AgNOR) and immunomarkation of the antigen of nuclear proliferation (PCNA) for their possible link with the morphostructural findings previously described. By means of argentic impregnation, the AgNOR were identified. The histometric was performed according to the numeric parameters of AgNOR per nucleus (CABRINI et al. 1992) immersed 1000x. A triple blind reading of the five randomly chosen studies from each of the twenty cases studies with distinct experimentation stages was completed. The results were compared to the normal areas (control group). The PCNA was determined immunohistochemically (Avidina-Biotina System Dako). The average number of AgNOR was 11 after eight days; 16 after fifteen days and 12 after twenty days of the experiment (100% adenocarcinoma). In the control group, the average number of AgNOR did not exceed 6. The PCNA after eight days was negative. The reaction in the tumor area was between 20 and 30% positive. The results indicate an increase in the number of AgNOR in relation to the neoplastic proliferation, corroborated by PCNA immunodetection.

Age-related histochemical and immunohistochemical changes in human labial salivary glands.

We here in determined the histochemical and immunological changes that salivary glands experience as a result of the ageing process. Samples from the inferior lip of children, youngsters and young adults were analyzed by histochemical techniques, Periodic-acid-Schiff, (PAS) Alcian blue (AB) (pHs 1.0 and 2.5) and Toluidine blue for mucosubstances and immunohistochemical staining of S 100 protein and cytokeratin 20, avidin-biotin system (DAB). In children, the techniques used evidenced various reaction degrees in the acinar cells, even within a single acinous. They displayed a slight metachromasia and were alcianophilic at pH 2.5. In youngsters, and especially in adults, glands showed a notable PAS positivity and alcianophilia at both pH levels, and an intense metachromasia. PS 100 was positive in the basal area of the acini and serous demilunes of all groups, the reactivity being higher in adults. Cytokeratin 20 was better observed in ductal cells from children glands. These findings suggest modifications at cytological level and in the chemical composition of the secretory granules, indicating possible functional variations in lip salivary glands related to the ageing process.