Whole Saliva has a Dual Role on the Adherence of Candida albicans to Polymethylmetacrylate.

Adhesion of Candida albicans to acrylic of dental prostheses or to salivary macromolecules adsorbed on their surface is believed to be a critical event in the development of denture stomatitis. In previous studies our group has shown that adhesion of C. albicans germ tubes to polystyrene is decreased by saliva whereas C. albicans yeast cells adhesion to the same material is enhanced. The results presented in this study confirm this dual role played by whole saliva, since it decreased the adhesion of germ tubes but increased the adhesion of yeast cells to polymethylmetacrylate (PMMA). These effects mediated by whole saliva do not seem to be related to an inhibition of the germination of C. albicans, since similar levels of filamentation were observed in presence and absence of saliva. These results may give new insights into the conflicting role of saliva in the adhesion of C. albicans to acrylic resins of dental prostheses.

Inhibition of adherence of Candida albicans and Candida dubliniensis to a resin composite restorative dental material by salivary secretory IgA and monoclonal antibodies.

OBJECTIVE: The attachment of Candida to oral surfaces is a crucial step in the colonization of the oral cavity and the eventual development of oral diseases caused by this microorganism. Inhibition of adhesion is one of the strategies currently studied to prevent Candida infections. The main objective of this study was to investigate the inhibitory effect of the human salivary components on the adherence of Candida albicans and C. dubliniensis to Herculite, a widely used resin composite restorative dental material. We have also investigated the influence on the adherence of three monoclonal antibodies (mAbs) directed against C. albicans cell wall antigens. DESIGN: The adhesion of three strains of C. albicans and one strain of C. dubliniensis was studied by a visual method after incubating the fungus and the resin in presence and in absence of human whole saliva, secretory immunoglobulin A (sIgA) and three mAbs directed against C. albicans cell wall surface antigens. RESULTS: Adherence of C. albicans was inhibited by whole saliva (41.7%), salivary sIgA (55.7%) and the salivary components that bind to the cell wall (36.7%). Whole saliva significantly reduced the adhesion of C. dubliniensis to Herculite to 45.3% of the control level. Saliva previously adsorbed with fungal cells or sIgA depleted saliva had no effect on adherence. An inhibition in the adhesion of C. albicans and C. dubliniensis to Herculite similar to that shown by whole saliva was also observed when mAbs C7 and 26G7 were used. However, mAb 21E6 increased adhesion of all the strains to Herculite. CONCLUSIONS: The results suggest that sIgA, as well as whole saliva, are important in blocking adherence of C. albicans and C. dubliniensis to Herculite and that this effect can be reproduced with mAbs directed against the cell wall surface of C. albicans.

Enfermedad injerto contra huésped crónica / Chronic graft versus host disease

Antecedentes: La enfermedad injerto contra huésped (EIVH) se produce cuando las células inmunocompetentes del donante generan una reacción inflamatoria contra un tejido del huésped inmunodeprimido, la cual compromete la piel, el hígado, la mucosa oral y ocular, y el tracto gastrointestinal. En la piel las manifestaciones son múltiples, secuenciales e indicadoras del pronóstico de la enfermedad. Objetivo: presentar la evolución clínica completa, durante dos años de control evolutivo, de una enfermedad injerto contra huésped crónica desarrollada en una paciente de sexo masculino, de 17 años, con trasplante de médula ósea (stem cells) alogénico periférico, HLA idéntico emparentado (hermana), para que las lesiones sean reconocidas y diagnosticadas por los dermatólogos. Diseño: se registraron día a día, durante dos años, todas las manifestaciones dermatológicas que fueron surgiendo a lo largo del tiempo, como también las transformaciones de las lesiones típicas de la fase temprana o liquenoide de la enfermedad, en lesiones esclerodermiformes características de la fase tardía.Materiales y métodos: las lesiones fueron confirmadas con estudios histopatológicos. Se realizaron exámenes complementarios específicos que demostraron el compromiso sistemático en el paciente. Resultados: se registró la evolución completa de una enfermedad injerto contra huésped crónica; se confirmó afección en la piel, hepática, ocular y de la mucosa oral. Conclusiones: destacamos la importancia para los médicos dermatólogos de conocer las múltiples manifestaciones cutáneas en las distintas etapas de la enfermedad injerto contra huésped crónica, ya que sus manifestaciones en piel son prioritarias e indicadoras del pronóstico de la enfermedad

Enfermedad injerto contra huésped crónica / Chronic graft versus host disease

Antecedentes: La enfermedad injerto contra huésped (EIVH) se produce cuando las células inmunocompetentes del donante generan una reacción inflamatoria contra un tejido del huésped inmunodeprimido, la cual compromete la piel, el hígado, la mucosa oral y ocular, y el tracto gastrointestinal. En la piel las manifestaciones son múltiples, secuenciales e indicadoras del pronóstico de la enfermedad. Objetivo: presentar la evolución clínica completa, durante dos años de control evolutivo, de una enfermedad injerto contra huésped crónica desarrollada en una paciente de sexo masculino, de 17 años, con trasplante de médula ósea (stem cells) alogénico periférico, HLA idéntico emparentado (hermana), para que las lesiones sean reconocidas y diagnosticadas por los dermatólogos. Diseño: se registraron día a día, durante dos años, todas las manifestaciones dermatológicas que fueron surgiendo a lo largo del tiempo, como también las transformaciones de las lesiones típicas de la fase temprana o liquenoide de la enfermedad, en lesiones esclerodermiformes características de la fase tardía.Materiales y métodos: las lesiones fueron confirmadas con estudios histopatológicos. Se realizaron exámenes complementarios específicos que demostraron el compromiso sistemático en el paciente. Resultados: se registró la evolución completa de una enfermedad injerto contra huésped crónica; se confirmó afección en la piel, hepática, ocular y de la mucosa oral. Conclusiones: destacamos la importancia para los médicos dermatólogos de conocer las múltiples manifestaciones cutáneas en las distintas etapas de la enfermedad injerto contra huésped crónica, ya que sus manifestaciones en piel son prioritarias e indicadoras del pronóstico de la enfermedad (AU)

Aminopeptidase activity in human saliva.

In this work, different aminopeptidase activity levels in whole human saliva are described. Aminopeptidase activities were studied by measuring the rate of hydrolysis of the artificial substrates Ala-, pGlu-, Pro-, Arg-, Asp- y Cis-2-naphthylamides (fluorimetrically detected at 412 rim with excitation at 345 nm). The presence of these enzyme activities in the saliva suggests that the active levels of saliva peptides can be controlled by homeostatic mechanism similar to those that have been described in other tissues, such as plasma, the central nervous system, and immunocompetent cells.

Actividad aminopeptidásica en la saliva humana / Aminopeptidase activity in human saliva

En el presente trabajo se describe la presencia de diferentes actividades aminopeptidásicas en la saliva humana total. La determinación de las actividades enzimáticas se llevó a cabo midiendo el ratio de hidrólisis de las muestras sobre los sustratos cromogénicos Ala-, pGlu-, Pro-, Arg-, Asp- y Cis-2-naftilamidas (detectadas fluorimétricamente a 345 nm de excitación y 412 de emisión). La presencia de estas actividades enzimáticas en la saliva sugiere que los niveles de péptidos activos a este nivel pueden ser controlados por mecanismos homeostáticos similares a los descritos en otros tejidos, como el plasma, el sistema nervioso central y el sistema inmune (AU)

[Comparison of the effects of the administration of fluoxetine and sertraline on the immune markers of the mu opioid receptor in the rat brain]. / Comparación de los efectos de la administración de fluoxetina y sertralina sobre el inmunomarcaje del receptor opioide mu en el cerebro de la rata.

INTRODUCTION: Chronic fluoxetine or imipramine administration in rats can generate a similar increase in the number of neural cells immunostained for mu opioid receptors in several prosencephalic regions. OBJECTIVE: The aim of the present work was to describe the effects of chronic sertraline administration on mu opioid receptor immunostaining in several rat brain prosencephalic regions, in order to compare with previously described fluoxetine effects. MATERIALS AND METHODS: Experimental animals were chronically administered with sertraline (i.p.). An immunocytochemical method, with the aid of a computerized image analysis system, was used in order to measure the number of neural cells immunostained for mu opioid receptors in several prosencephalic regions. RESULTS: Although chronic sertraline administration in rats generates a significant increase in the number of neural cells immunostained for mu opioid receptors in the caudatus-putamen, dentate gyrus, lateral septum and the frontal, parietal and piriform cortices, slight regional differences, with respect to fluoxetine action, were found. Thus, a more marked action on parietal cortex and lateral septum, and a lesser action on the frontal cortex, were found. CONCLUSION: Regional differences in sertraline effects, with respect to fluoxetine, could be related to a lesser incidence of psychomotor impairment.

Infraorbital nerve transection increases NADPH-diaphorase activity in the rat mesencephalic trigeminal nucleus.

Complete information concerning possible alterations in nitric oxide production in the rat brainstem trigeminal system after peripheral nerve lesion is still lacking. This being the case, density of NADPH-diaphorase positive neurons in the trigeminal mesencephalic nucleus after experimental infraorbital nerve transection was studied. In the lesioned side, an ipsilateral increase in NADPH-d positive neurons was found at postoperative days 4 and 6 with respect to contralateral, without changes after a 2 months period. These data suggest that nitric oxide could be involved in regeneration of afferent fibers concerned with the periodontal receptors of maxillary teeth.

Effects of acute lidocaine administration on the rat prosencephalic enkephalinergic system.

Lidocaine is a local anesthetic widely used in therapeutics and as antiarrhythmic agent. However, information concerning possible alterations in the enkephalinergic system after acute treatment with this substance is not complete. This being the case, we focused on analyzing enkephalin immunostaining in several regions of the rat brain after lidocaine administration. We could not find significative changes in rat prosencephalon. These data might suggest that the enkephalinergic system is not altered by lidocaine.

Acid, basic and neutral soluble and membrane-bound aminopeptidase activities after lidocaine administration in discrete areas of the rat brain.

It has been suggested that aminopeptidase activity could play an important role in the regulation and biotransformation of several neuroactive peptides. Lidocaine is a local anesthetic widely used in therapeutics and as antiarrhythmic agent. However, information concerning possible alterations in the neuropeptide metabolism after treatment with this anesthetic is lacking. This being the case, in the present paper we have studied the activities of three aminopeptidases (Asp-, Leu- and Lys-aminopeptidase) in several brain areas after lidocaine administration. The study includes the activities of the soluble and membrane-bound forms. Soluble neutral and basic aminopeptidase activities show significant decreases after lidocaine administration in the frontal cortex. Soluble Lys-aminopeptidase also shows a significant decrease in the pituitary gland. On the other hand, membrane-bound Leu-aminopeptidase activity shows significant decreases not only in the frontal, but also in the parietal cortex and in the thalamus. These data might suggest that the neuropeptide transmission and/or modulation could be activated by lidocaine.