Comparative effects of retinoic acid or glycolic acid vehiculated in different topical formulations.

Retinoids and hydroxy acids have been widely used due to their effects in the regulation of growth and in the differentiation of epithelial cells. However, besides their similar indication, they have different mechanisms of action and thus they may have different effects on the skin; in addition, since the topical formulation efficiency depends on vehicle characteristics, the ingredients of the formulation could alter their effects. Thus the objective of this study was to compare the effects of retinoic acid (RA) and glycolic acid (GA) treatment on the hairless mouse epidermis thickness and horny layer renewal when added in gel, gel cream, or cream formulations. For this, gel, gel cream, and cream formulations (with or without 6% GA or 0.05% RA) were applied in the dorsum of hairless mice, once a day for seven days. After that, the skin was analyzed by histopathologic, morphometric, and stereologic techniques. It was observed that the effects of RA occurred independently from the vehicle, while GA had better results when added in the gel cream and cream. Retinoic acid was more effective when compared to glycolic acid, mainly in the cell renewal and the exfoliation process because it decreased the horny layer thickness.

Effects of zinc during lactation on the junctional epithelium and inserted gum in rats / Efectos del zinc durante la lactancia sobre el epitelio de unión y la encía insertada en ratas

The purpose of this study was to evaluate the effects of zinc, during lactation, on the junctional epithelium and inserted gum of the first upper molar of rats. The study used one-day old male rats, divided into two groups: those whose mother had been treated with 300 mg zinc chloride (ZnCl2) in the drinker water (treated group), and those whose mothers did not receive ZnCl2 (control group). After 21 days, the rat pups were sacrificed. Using karyometrical techniques, the greater (D) and smaller (d) nuclear diameters of the different layers of the junctional and inserted gum epithelia were determined, and the mean geometric diameter, D/d ratio, perimeter, area, volume, volume/area ratio, eccentricity, shape coefficient, and the contour index were estimated. The 100-point Merz grid was used with the purpose of evaluating the citoplasmatic and celular volume, the nucleus/citoplasm relationship, number density, outer surface/basal layer ratio, the thickness of epithelial layers, and the surface density. The results were submitted to statistical analysis using the Wilcoxon-Mann-Whitney test. The nuclei of the studied structures were significantly smaller, and the stereological results demonstrated that there were smaller cells, hence meaning a greater number of cells per mm3 of tissue, in the treated group. Zinc caused changes on the studied epitheliums, according to morphometric and stereological evaluations.

El objetivo de este estudio fue evaluar los efectos del zinc durante la lactancia, sobre el epitelio de unión y la encía insertada del primer molar superior de ratas. Fueron utilizadas ratas macho de un día de edad, divididas en dos grupos: aquellas cuyas madres habían sido tratadas con 300 mg de cloruro de zinc (ZnCl2) con agua del bebedero (grupo tratado) y aquellas cuyas madres no recibieron ZnCl2 (grupo control). Las crías fueron sacrificadas después de 21 días. Utilizando técnicas cariométricas fueron medidos los diámetros mayor (D) y menor (d) de los núcleos de las células de los diferentes estratos del epitelio de unión y de la encía insertada, estimándose el diámetro geométrico medio, la relación D/d, perímetro, área, volumen, relación volumen/área, excentricidad, coeficiente de forma e índice de contorno. Fue usada la rejilla de Merz, de 100 puntos, con la finalidad de evaluar el volumen celular y citoplasmático, la relación núcleo/citoplasma, densidad numérica, relación superficie externa/superficie basal, espesor de las capas epiteliales y densidad de superficie. Los resultados fueron sometidos a análisis estadístico mediante el test de Wilcoxon-Mann-Whitney. En el grupo tratado los núcleos celulares de las estructuras estudiadas fueron significativamente menores y los resultados estereológicos demostraron que las células eran menores, por lo tanto, con mayor número por mm3 de tejido. De acuerdo a los resultados morfométricos y estereológicos, el zinc provocó cambios en los epitelios estudiados.

Alteraciones histopatológicas de placentas de ratones infectadas con diferentes cepas de Trypanosoma cruzi / Histopathological alterations of placentas from mice infected by different Trypanosoma cruzi strains

El objetivo del presente estudio fue evaluar las alteraciones histopatológicas de las placentas provocadas por la infección materna durante la preñez con diferentes cepas de Trypanosoma cruzi. Ratones preñadas, de 60 días de edad, fueron inoculadas por la via intraperitoneal (i.p.) con 2 x 105 tripomastigotes sanguíneos de las cepas colombiana, Y, Bolivia o RC del T. cruzi. Los resultados mostraron que las cepas Bolivia y RC presentan mayor histotropismo por las células placentarias del ratón que las cepas colombiana e Y. El proceso inflamatorio afectó la decidua basal en todos los grupos de ratones infectados, mientras que la cepa colombiana causó intensa degeneración de la decidua basal, con células inflamatorias escasas o ausentes. Las placentas de todos los grupos infectados presentaron áreas de edema, degeneración, necrosis y calcificación, principalmente en la decidua basal. En los animales inoculados con la cepa RC del T. cruzi también fue afectado el trofoblasto de la zona esponjosa. El parasitismo más intenso fue observado en los animales infectados con las cepas Bolivia y RC, envolviendo todas las zonas placentarias, incluso las células trofoblásticas gigantes y el trofoblasto esponjoso. Los resultados permiten concluir que las placentas sufren procesos patológicos diferentes, característicos para cada cepa del T. cruzi.

The objective of the present study was to evaluate the histopathological alterations of the placenta provoked by maternal infection during pregnancy by different Trypanosoma cruzi strains. Pregnant mice, 60 day-old, were i.p. inoculated with 2 x 105 bloodstream trypomastigotes of colombian, Y, Bolivia or RC strains of T. cruzi. The results demonstrated that the Bolivia and RC strains showed higher histotropism for the mouse placental cells than the colombian or Y strains. The inflammatory process in all the infected groups involved the basal decidua, but the colombian strain caused intense decidual degeneration, with rare or absent inflammatory cells. Placentas from all the infected groups displayed aéreas of edema, degeneration, necrosis and calcification, mainly in the basal decidua, but the group infected by the RC strain showed also involvement of the spongiotrophoblast. The highest parasitism was observed with the Bolivia and RC strains, involving all the placenta zones, including the trophoblast giant cells and the spongiotrophoblast. The results show that placentas undergo differentiated pathological processes, characteristic for each strain.

Ultrastructure of submandibular salivary glands of mouse: TEM and HRSEM observations.

The fine structure of submandibular glands of mouse were analyzed using light microscopy (LM), high resolution scanning electron microscopy (HRSEM), and transmission electron microscopy (TEM) methods. For LM, the specimens were embedded in Spurr resin, stained by toluidin blue solutions. For TEM, the tissues of submandibular salivary glands were fixed with modified Karnovsky solution and postfixed with osmium tetroxide. For HRSEM, the tissues were fixed with 2% osmium tetroxide solution in 1/15M sodium phosphate buffer (pH 7.4). The samples were immersed successively in dymethylsulphoxide and freeze cracked. The maceration was made in diluted osmium tetroxide for 24-48 h. The samples were examined by high resolution scanning electron microscopy. The intracellular components of acinar and ductal cells revealed clearly the Golgi apparatus, rough endoplasmic reticulum, secretory granules, and mitochondria. The end bulbs of Golgi lamellae and flattened cisterns of rough endoplasmic reticulum showed the luminal surface. A few mitochondria were identified intermingling between the rough endoplasmic reticulum and the mitochondriales cristae in three-dimensional HRSEM images. Secretory granules were numerous and presented different sizes. Small granules of ribosomes were attached on cistern surface, measuring 20-25 nm in diameter. Numerous arranged microvilli were found on the luminal surface of secretory canaliculus. The contact surfaces of acinar cells revealed complicated interdigitations by cytoplasmic processes. The mitochondria of duct cells were disposed vertically and surrounded by basal infoldings of plasma membranes. Basement membrane showed a spongy-like structure having an irregular surface with various strands and meshes of fine collagen fibrils.

Effect of sodium cyclamate on the rat fetal exocrine pancreas: a karyometric and stereological study / Efectos del ciclamato de sodio en el pancreas exocrino fetal de ratas: estudio cariométrico y estereológico

The cyclamate, a sweetner substance derived from N-cyclo-hexyl-sulfamic acid, is largely utilized as a non-caloric artificial edulcorant in foods and beverages as well as in the pharmaceutical industry. The objective of this study was to evaluate karyometric and stereological alterations in the rat fetal pancreas resulting from the intraperitoneal administration of sodium cyclamate. The exocrine pancreas of ten fetuses of rats were evaluated, five treated and five controls chosen at random, in which five rats that received from the 10th to 14th days of pregnancy an intraperitoneal daily injection of sodium cyclamate at 60 mg/Kg of body weight during 5 days. At the 20th day of gestation, the animals were removed and weighed, as were their placentas; the length of the umbilical cords also were measured. After the laboratory processing, semi-seriated 6mm cuts stained with haematoxyline and eosine were performed. In seven karyometric parameters (major, minor, and medium diameters, volume, area, perimeter, and volume-area ratio), the increase was statistically significant in the treated group when compared with control group. Stereological parameters showed in the treated group a significant increase in the cellular volume and a significant reduction in the numerical cellular density. These results showed that the sodium cyclamate in pregnant rats led to retardation of fetal development and hypertrophy in the exocrine pancreas of the rat fetuses.

El ciclamato, es una substancia derivada del ácido N-ciclo-hexil-sulfámico, bastante usada como edulcorante no calórico en los alimentos y bebidas, así como en la industria farmacéutica. El objetivo de este estudio fue evaluar las alteraciones cariométricas y estereológicos en páncreas fetal de rata tras la administración intraperitoneal de ciclamato de sodio. El páncreas exocrino de diez de los fetos de rata fueron evaluados, cinco tratados y cinco controles seleccionados al azar, en el que cinco ratas recibieron del día 10 al día 14 de preñez una inyección intraperitoneal diaria de ciclamato de sodio a 60 mg/Kg de peso corporal durante 5 días. En el día 20 de gestación, los animales fueron retirados y pesados, al igual que sus placentas. Asimismo, se midió la longitud de los cordones umbilicales. Después del procesamiento de laboratorio, cortes semi-seriados de 6µm, se tiñeron con hematoxilina-eosina. En siete parámetros cariométricos (diámetros mayor, menor y medio, volumen, área, perímetro y relación área/volumen). El aumento fue estadísticamente significativo en el grupo tratado comparado con el grupo control. Los parámetros estereológicos mostraron en el grupo tratado un aumento significativo del volumen celular y una reducción significativa en la densidad numérica celular. Estos resultados mostraron que el uso del ciclamato de sodio en las ratas preñadas causa retardo en el desarrollo fetal e hipertrofia en el páncreas exocrino de los fetos de rata.

Efectos del cloruro de cobalto sobre el epitelio de unión y epitelio reducido del esmalte del primer molar superior de rata / Effects of cobalt chloride in junctional epithelium and reduced enamel epithelium of the rat maxillary first molar

El cobalto es uno de los principales componentes de las aleaciones metálicas fundidas, usadas frecuentemente en odontología. El metal es el constituyente de 45 a 70 por ciento de los trabajos protéticos. En virtud de la existencia de evidencias que elementos metálicos pueden causar toxicidad sistémica y local, este trabajo tuvo como objetivo evaluar los efectos del cobalto sobre el epitelio de unión y el epitelio del esmalte del primer molar superior de rata, durante la lactancia. Con esa finalidad fueron usadas ratas con 1 día de vida postnatal, cuyas madres recibieron 300 mg de cloruro de cobalto por litro de agua destilada en el bebedero, durante a la lactancia. Al cabo de 21 días, las crías fueron sacrificadas con sobredosis anestésica. Las cabezas fueron separadas, fijadas en "alfac", descalcificadas e incluidas en parafina. Fueron utilizados cortes frontales seriados teñidos con hematoxilina y eosina. Fueron estimados los siguientes parámetros nucleares: diámetros mayor, menor y geométrico medio, relación entre diámetros, perímetro, área, volumen, relación entre volumen y área, excentricidad, coeficiente de forma e índice de contorno. Mediante métodos estereológicos fueron evaluados: relación núcleo/citoplasma, volumen celular, densidad numérica celular, relación superficie externa/camada basal, espesor de las camadas epiteliales y densidad de superficie. Todos los datos obtenidos fueron sometidos a análisis estadístico mediante la prueba no-paramétrica de Wilcoxon-Mann-Whitney. Los núcleos de los tejidos estudiados mostraron valores menores para diámetros, perímetro, área, volumen y relación volumen/área. Estereológicamente, fue posible observar en el epitelio de unión y en el epitelio reducido del esmalte, células menores con citoplasma más escaso, lo que se refleja en mayor número de células por mm3 de tejido. En este estudio, el cobalto ocasionó un cuadro de atrofia epitelial, sugiriendo una acción directa sobre los epitelios de unión y del esmalte.

Cobalt is one of the main components of cast metal alloys broadly used in dentistry. It is the constituent of 45 to 70 percent of numerous prosthetic works. There are evidences that metal elements cause systemic and local toxicity. The purpose of the present study was to evaluate the effects of cobalt on the junctional epithelium and reduced enamel epithelium of the first superior molar in rats, during lactation. To do this, 1-day old rats were used, whose mothers received 300mg of cobalt chloride per liter of distilled water in the drinker, during lactation. After 21 days, the rat pups were killed with an anesthetic overdose. The heads were separated, fixed in "alfac", decalcified and embedded in paraffin. Frontal sections stained with hematoxylin and eosin were employed. Karyometric methods allowed to estimate the following parameters: biggest, smallest and mean diameters, D/d ratio, perimeter, area, volume, volume/area ratio, eccentricity, form coefficient and contour index. Stereologic methods allow to evaluate: cytoplasm/nucleus ratio, cell and cytoplasm volume, cell number density, external surface/basal membrane ratio, thickness of the epithelial layers and surface density. All the collected data were subjected to statistic analysis by the non-parametric Wilcoxon-Mann-Whitney test. The nuclei of the studied tissues showed smaller values after karyometry for: diameters; perimeter, area, volume and volume/area ratio. Stereologically, it was observed, in the junctional epithelium and in the reduced enamel epithelium, smaller cells with scarce cytoplasm, reflected in the greater number of cells per mm3 of tissue. In this study, cobalt caused epithelial atrophy, indicating a direct action on the junctional and enamel epithelium.

Efectos del cadmio sobre las glándulas salivales de rata: durante la lactancia / Effects of cadmium on the rat salivary glands: during lactation

El cadmio (Cd), presente en el aire, agua potable y alimentos, tiene potencial para afectar la salud humana, principalmente en las regiones altamente industrializadas. El Cd además de afectar la función placentaria, puede atravesar la barrera placentaria y perjudicar directamente el desarrollo fetal. En virtud de que el organismo es particularmente susceptible a la exposición al Cd durante el período perinatal, y que ese metal puede ser excretado en la leche, el objetivo del presente trabajo fue estudiar los efectos de la exposición continua a agua potable conteniendo bajos niveles de Cd durante la lactancia sobre las glándulas salivales de la rata. Ratas hembra recibieron agua potable conteniendo 300mg/l de CdCl2 ad libitum durante toda la lactancia. Animales control recibieron un volumen similar de agua potable sin Cd. Las ratas lactantes (21 días de edad) fueron sacrificadas con una dosis letal de anestésico. Las glándulas salivales fueron separadas, fijadas en "alfac" por 24 h, y cortadas seriadamente. Cortes de 6 µm de espesor fueron teñidos con hematoxilina y eosina. Fueron estimados los parámetros nucleares, los volúmenes citoplasmático y celular, la relación núcleo/citoplasma, densidad numérica, densidad superficial, diámetros y espesor de las paredes de las estructuras glandulares. El peso medio corporal fue 34,86 g para la rata control y 18,56 g para la tratada. Histológicamente, los adenómeros glandulares fueron significativamente menores y los conductos glandulares fueron similares en ambos grupos. La estroma fue más abundante en los animales tratados. En conclusión, las glándulas salivales (submandibular, parótida y sublingual) mostraron retardo del crecimiento en los animales intoxicados por Cd.

Cadmium (Cd) in air, drinking water and food has the potential to affect the health of people, mainly those who live in highly industrialized regions. Cd affects placental function, can cross the placental barrier and directly modify fetal development. Once the organism is particularly susceptible to the exposition to the Cd during the perinatal period, and that this metal can be excreted in the milk, the aim of the present work was to study the effects of the constant exposition to drinkable water containing low levels of Cd during the lactation, on the salivary glands of the rat. Female rats received ad libitum drinking water containing 300mg/l of CdCl2 throughout the whole lactation. Control animals received a similar volume of water without Cd. Lactant rats, (21 day old) were killed by lethal dose of anesthetic. The salivary glands were separated, fixed in "alfac" solution for 24 h, and serially sectioned. The 6mm thick sections were stained with hematoxylin and eosin. Nuclear glandular parameters were estimated, as well as cytoplasm and cell volume, nucleus/cytoplasm ratio, number and surface density, diameters and cell thickness. Mean body weight was 34.86 g for the control group and 18,56 g for the Cd-treated group. Histologically, the glandular acini were significantly smaller, the gland ducts were similar in both groups studied. The connective tissue was more abundant. In conclusion, the salivary glands (submandibular, parotid and sublingual) showed retarded growth after Cd intoxication.

Histometric study of alveolar bone in rats submitted to ethanol during lactation

The present work studied the adverse effects of maternal exposure of rats to alcohol during lactation, on the development of their off spring. Histometric evaluation by karyometry and of the alveolar bone at the level of the first upper molar of the sucking was perfomed. Two groups of animals, one coming from mothers exposed to drinking water containing 20 percent ethanol during the total lactation period and the other of controls coming from mothers receiving only alcohol-free drinking water during this period. On the 21 first day of lactation the young of each group were aleatorily selected and following anesthesia, their heads severed; after histological treatment, serial 6 ìm sections on the frontal plane at the molar level, stained with hematoxilin and eosin, were obtained. The experimental results produced, suggest that sucking from ethanol-treated mothers, show retarded post-natal growth, their alveolar bones presenting scarce, little calcified trabeculae, and a more abundant bone marrow compared to controls.

Considerando que la lactancia es un período importante y vulnerable, y que la exposición materna al alcohol durante esta fase puede provocar efectos adversos en las crías en desarrollo, el propósito del presente trabajo es evaluar histométricamente (mediante cariometría y estereología), el hueso alveolar a nivel del primer molar superior, de ratas lactantes sometidas a los efectos del etanol. Con esa finalidad utilizamos dos grupos, uno que recibió etanol al 20 por ciento en el bebedero, durante todo el período de lactancia (21días), y otro que recibió solo agua. En el 21° día de lactancia, 5 ratas de cada grupo fueron aleatoriamente seleccionadas. Después de sacrificados, los animales fueron fijados en formol al 10 por ciento. Las cabezas, separadas de los cuerpos, fueron incluidas en parafina, y cortadas seriadamente con 6 Lim de grosor, a partir de un plano frontal al nivel de los molares, y teñidas con hematoxilina y eosina. Basados en los resultados presentes, es posible concluir que el etanol al 20 por ciento en el agua de beber, administrado a ratas lactantes, provoca los siguientes efectos: reducción significativa del peso corporal, alteraciones de las trabéculas del hueso alveolar, observadas estereológicamente, evidenciadas por trabéculas delicadas y poco calcificadas, con médula abundante, núcleos menores en osteoblastos y osteocitos y más achatados en los primeros, y con osteocitos de volúmenes citoplasmático y celular menor y densidad numérica mayor.

Estudio cariométrico de placentas de ratones con infección aguda por diferentes cepas de Trypanosoma cruzi / Karyometric study of placentas from mice with acute infection by different strains of Trypanosoma cruzi

El objetivo de este trabajo fue evaluar cariometricamente las alteraciones causadas por diferentes cepas de T. cruzi en la placenta del ratón. Ratones hembras de 60 días, grávidas, fueron inoculadas, intraperitonealmente, con 2 x 10(5) tripomastigotes sanguíneos de las cepas colombiana, Y, Solivia o RC del T. cruzi. Fueron observadas claras diferencias en las alteraciones cariométricas de las células trofoblásticas gigantes y de las células trofoblásticas de la zona esponjosa. Los resultados demostraron que las cepas colombiana y RC causan alteraciones tanto en las células trofoblásticas gigantes como en las células del trofoblasto esponjoso, mientras que las cepas Y y Bolivia provocan alteraciones solamente en las células trofoblásticas gigantes. Es posible concluir que cada cepa posee características propias y que, a pesar del tipo similar de transmisión, presenta matices diferenciales en el proceso de la patogénesis placentaria.

The objective of this work was to evaluate karyometrically the alterations caused by different strains of Trypanosoma cruzi in the mouse placenta. Pregnant mice, 60-day old, were intraperitoneally inoculated with 2 x 10(5) bloodstream trypomastigotes of the Colombian, Y, Bolivia or RC strain of T cruzi. There were observed clear differences in the karyometric alterations of the trophoblast giant cells and in the spongiotrophoblast cells. The results demonstrate that the Colombian and RC strains cause alterations both in the trophoblast giant cells and in the spongiotrophoblast cells, whereas the Y and Bolivia strains provoke alterations only in the trophoblast giant cells. It is possible concluding that each strain has its own characteristics and that, in spite of the similar type of transmission, it show differential nuances in the placental pathogenic process.

Análise morfológica e morfométrica do tecido subcutâneo de ratos submetidos àação de pasta de hidróxido de cálcio e óleo de Ricinus communis / Morphological and morphometrical analysis of the subcutaneous tissue of rats submitted to the action of calcium hydroxide paste and Ricinus communis oil

Neste presente estudo foram comparadas duas composições de pastas medicamentosas para utilização intracanal: pasta de hidróxido de cálcio e óleo de Ricinus communis e pasta de hidróxido de cálcio e polietilenoglicol. Tubos de polietileno foram implantados no tecido subcutâneo de 9 ratos, sendo 2 escapulares e 2 pélvicos, totalizando 4 tubos por animal, cada par com uma das pastas. O grupo controle foi definido pela lateral do tubo. Após 7, 21 e 42 dias os animais foram sacrificados e os tecidos processados para obtenção dos cortes histológicos e posterior análise histopatológica. Os resultadosforam classificados quanto à severidade da reação inflamatória e quantificados em relação aos eventos presentesnas áreas pré-determinadas. Observou-se à análise morfológica, que ambas as pastas apresentaram índice de inflamação intenso aos 7 dias - pasta A (29,7) e pasta B (39,3), persistindo até aos 21 dias (pasta A – 27,1; pasta B – 27,9). Aos 42 dias a reação tecidual foi moderada (pasta A – 12,4; pasta B – 13,0). Comparando-se ao grupo controle, percebeu-se que este apresentava reação tecidual indo do moderado (14,2 aos 7 dias e 10,0 aos 21 dias) ao discreto (7,8 aos 42 dias).Quando submetidos à análise estatística (ANOVA – Tukey – p< .01) esses valores apresentaram diferença estatisticamente significante para todas as pastas e grupo controle. Concluiu-se que ambas as pastas apresentaram-se como irritantes ao tecido conjuntivo, permitindo colagenização progressiva da cápsula junto à abertura tubular. Porém, a pasta com óleo de Ricinus communis (Pasta A) apresentou potencial irritativo estatisticamente menor que a Pasta B.

Histometría de la glándula sublingual de ratones (Mus musculus) machos y hembras infectados con la cepa RAL del parásito de Chagas, Trypanosoma cruzi

Histometry of the sublingual gland in male and female mice (Mus musculus) infected with the RAL strain of the Chagas parasite, Trypanosoma cruzi. The aim of this work was to analyze histologically and histometrically the sublingual gland of mice infected with the RAL strain of T. cruzi, according to the sex. Swiss mice (Mus musculus) were inoculated with 2x104 blood trypomastigotes of the RAL strain of T. cruzi. in the peak of the parasitemia (12th day) the mice were sacrificed, and the sublingual glands were fixed in ALFAC. HE-stained histological sections were evaluated histometrically. The parasitemia was higher in females. Histopatologically, acini of the infected animals were smaller, with scanty production of secretion, and smaller striated ducts. The nuclei of the demilunes were smaller and showed amastigote nests in the cytoplasm. Karyometrically, nuclei of the acini, demilunes and striated ducts were smaller in the infected mice. Stereologically, it was observed that relative volumes of acini and ducts were smaller and, inversely, relative volumen were greater for the conjunctive tissue in the infected males. The surface densities of acini and ducts were bigger and the diameter and thickness of the wall were smaller in this group. On the other hand, relative volume of acini was smaller and those of the ducts and conjunctive tissue were bigger in the infected females. The diameter and thickness of the wall of acini were smaller, and those of the striated ducts were bigger in this group. The RAL strain of T. cruzi caused general atrophy in the sublingual gland, with numerous nests of parasites in the glandular parenchyma. Rev. Biol. Trop. 56 (2): 459-471. Epub 2008 June 30.

Analizamos morfológica e histométricamente la glándula sublingual de ratones infectados con la cepa RAL del Trypanosoma cruzi, en machos y hembras. Usamos ratones albinos (Mus musculus), variedad Swiss, inoculados con 2x104 tripomastigotes sanguíneos de la cepa RAL del T. cruzi.. Sacrificamos los animales en el pico de la parasitemia (12º día) y fijamos las glándulas sublinguales en ALFAC. Los cortes histológicos teñidos con HE fueron evaluados histométricamente (cariometría y estereología). La parasitemia fue más elevada en las hembras. Histopatológicamente, los "ácinos" (acini) de los animales infectados eran menores, con escasa secreción, y conductos estriados menores. Los núcleos de las "medialunas" eran menores y había nidos de amastigotes en el citoplasma. Cariométricamente, los núcleos de los ácinos, medialunas y conductos estriados eran menores en los ratones infectados. Estereológicamente, los volúmenes relativos ocupados por ácinos y conductos estriados fueron menores e, inversamente, fue mayor el volumen para el tejido conjuntivo de los machos infectados. Las densidades de superficie de ácinos y conductos fueron mayores, y el diámetro y el espesor de la pared menores, en este grupo. Por otro lado, la densidad de ácinos fue menor, y las de los conductos estriados y tejido conjuntivo, fueron mayores en las hembras infectadas. Las densidades de superficie de ácinos y conductos estriados fueron mayores, mientras que el diámetro y espesor de la pared de los ácinos fueron menores (y las de los conductos estriados mayores), en este grupo. La cepa RAL del T. cruzi causó un cuadro general de atrofia general en la glándula sublingual, con numerosos nidos de parásitos.

[Histometry of the sublingual gland in male and female mice (Mus musculus) infected with the RAL strain of the Chagas parasite, Trypanosoma cruzi]. / Histometria de la glándula sublingual de ratones (Mus musculus) machos y hembras infectados con la cepa RAL del parásito de Chagas, Trypanosoma cruzi.

The aim of this work was to analyze histologically and histometrically the sublingual gland of mice infected with the RAL strain of T. cruzi, according to the sex. Swiss mice (Mus musculus) were inoculated with 2 x 10(4) blood trypomastigotes of the RAL strain of T. cruzi. In the peak of the parasitemia (12th day) the mice were sacrificed, and the sublingual glands were fixed in ALFAC. HE-stained histological sections were evaluated histometrically. The parasitemia was higher in females. Histopatologically, acini of the infected animals were smaller, with scanty production of secretion, and smaller striated ducts. The nuclei of the demilunes were smaller and showed amastigote nests in the cytoplasm. Karyometrically, nuclei of the acini, demilunes and striated ducts were smaller in the infected mice. Stereologically, it was observed that relative volumes of acini and ducts were smaller and, inversely, relative volumen were greater for the conjunctive tissue in the infected males. The surface densities of acini and ducts were bigger and the diameter and thickness of the wall were smaller in this group. On the other hand, relative volume of acini was smaller and those of the ducts and conjunctive tissue were bigger in the infected females. The diameter and thickness of the wall of acini were smaller, and those of the striated ducts were bigger in this group. The RAL strain of T. cruzi caused general atrophy in the sublingual gland, with numerous nests of parasites in the glandular parenchyma.

Newly formed bone in mandible decortication experimental model using rhBMP-2 evaluated by densitometric study / Tejido óseo neoformado en el modelo experimental de la retirada de la cortical ósea mandibular utilizando rhBMP-2

The purpose of this study was to evaluate the newly formed bone, comparing two different carriers for rhBMP-2, using the decortication and nondecorticatication surgical technique in Wistar rat mandibles, evaluated by radiographic densitometry method. It was used fifty six animals according to specific treatment, which were sacrificed after 3 and 6 weeks after this. It was concluded that the decortication surgical technique was able to optimize the osteoinduction properties of the rhBMP-2, independently of the material carrier used and the period of time, according to radiographic densitometry technique.

El propósito de este estudio es evaluar la neoformación ósea con la densitometría radiográfica, comparando dos transportadores diferentes para el rhBMP-2, mediante la técnica quirúrgica con o sin la retirada previa de la cortical ósea, en mandíbulas de ratas Wistar. Fueron utilizados 56 animales, de acuerdo con el tratamiento específico, sacrificados después de 3 y 6 semanas. La densitometría radiográfica permitió concluir que la técnica quirúrgica de retirada de la cortical puede optimizar las características osteoinductoras del rhBMP-2, independientemente del transportador usado y del tiempo transcurrido.

Histometric Study of the Epithelium of Rats Submitted to Ethanol During Lactation / Estudio Histométrico del Epitelio de Ratas Sometidas al Etanol Durante la Lactancia

The present work studied the adverse effects of maternal exposure of rats to alcohol during lactation, on the development of their offspring. Histometric evaluation by karyometry and of the palatine epithelium of the sucking was performed. Two groups of animals, one coming from mothers exposed to drinking water containing 20% ethanol during the total lactation period and the other of controls coming from mothers receiving only alcohol-free drinking water during this period. On the 21 first day of lactation the young of each group were aleatorily selected and following anesthesia, their heads severed; after histological treatment, serial 6 -J,m sections on the frontal plane at the molar level, stained with hematoxilin and eosin, were obtained. The experimental results produced, suggest that suckling from ethanol-treated mothers, show a significant decrease of body weight, significant alterations of karyometric and stereological measurements that determined hypotrophy of palatine epithelial cells and toxicity of ethanol at the palatine epithelium.

El presente trabajo tiene por objetivo estudiar en ratas los efectos adversos de la exposición materna al alcohol durante la lactancia, en el desarollo de sus crías. Fue evaluado histométricamente (cariometría y estereología) el epitelio palatino de las críass. Fueron utilizados dos grupos: uno tratado con etanol al 20% en agua de bebedero, durante toda la lactancia; y control, recibió solamente agua. En el día 21° de la lactancia, cinco crías de cada uno de los grupos, fueron seleccionadas al azar, anestasiadas las cabezas de ellas fueron separadas de los cuerpos. Después del tratamiento histológico, fueron obtenidos cortes seriados de 6 um del plano frontal, a nivel de los molares y coloreados con hematoxilina eosina. Los resultados sugieren que lactantes de las madres tratadas con etanol al 20% en el bebedero, presentaron disminución significativa del peso corporal, alteraciones importantes de las medidas cariométricas y estereológicas, que determinaron hipotrofia de las células epiteliales del paladar y toxicidad del etanol en el epitelio palatino.

Uso de uma técnica histológica adequada para análise microscópica dos tecidos corono-radiculares de dentes permanentes, variando-se a solução descalcificadora / Histological technique suitable to microscopic analysis of tissues of permanent teeth

A escolha do fixador e do tempo de fixação, a técnica de descalcificação e as soluções usadas com esse objetivo são fatores importantes na obtenção de uma preparação correta para as mais diversas análises ao microscópio de luz. Assim, no presente trabalho de pesquisa, foi selecionada a técnica mais adequada de preparo de cortes histológicos para dentes permanentes, variando-se as soluções descalcificadoras. Para tanto, 8 terceiros molares humanos recém-extraídos, divididos randomicamente em 2 grupos de 4 dentes, foram fixados durante 7 dias em uma solução de Formol à 10 por cento e, em seguida, descalcificados por um período de 27 dias em uma solução de Ácido Nítrico a 4 por cento (Grupo I) e 42 dias em uma solução de Citrato de Sódio a 20 por cento + Ácido Fórmico a 30 por cento, em partes iguais (Grupo II). As etapas laboratoriais seguintes foram àquelas utilizadas rotineiramente e a coloração, segundo as técnicas da Hematoxilina-Eosina e doTricrômico de Gomori. Os cortes histológicos assim obtidos foram selecionados, analisados microscopicamente e fotografados. Pôde-se, assim, concluir, a partir dos resultados obtidos pela análise microscópica, que a técnica Histológica com a solução descalcificadora constituída pelo Citrato de Sódio a 20 por cento + Ácido Fórmico a 30 por cento obteve melhor desempenho, pois apresentou uma preservação mais satisfatória dos tecidos dentais observados.

Biochemical Analysis by Calcium Determination on the Newly Formed Bone in Critical Bone Defects Submitted to Different Treatments: A Pilot Study / Análisis Bioquímico para la Determinación de Calcio en Hueso Neoformado con Defectos Críticos Sometidos a Diferentes Tratamientos: Estudio Piloto

The aim of this study was to evaluate the calcium dosage of the newly formed bone, in critical bone defects created on the calvarial tissue and filled by different substances, in male Wistar rats. A cylindrical critical bone defect (6x2mm) was created in the posterior portion, left side, on the calvarial bone in nine animals and filled with: animals' coagulum, monoolein gel, poloxamer gel, monoolein gel + 1µg rhBMP-2, monoolein gel + 3µg rhBMP-2, monoolein gel + 7µg rhBMP-2, poloxamer gel + 1µg rhBMP-2, poloxamer gel + 3µg rhBMP-2, poloxamer gel + 7µg rhBMP-2. The results of this study showed a positive correlation between the calcium dosage analysis and the newly formed bone.

El propósito de este estudio fue evaluar el contenido de calcio del hueso neoformado, en defectos óseos críticos provocados en la bóveda craneana y rellenados con diferentes substancias, en ratas Wistar machos. Un defecto crítico cilindrico (6x2mm) fue provocado en el lado izquierdo de la porción posterior del hueso de la bóveda craneana, en nueve animales y rellenado con coágulo sanguíneo del propio animal, gel de monoleina, gel de poloxamer, gel de monoleina + 1µg,g de rhBMP-2, gel de monoleina + 3µg rhBMP-2, gel de monoleina + 7µg rhBMP-2, gel de poloxamer + 1µg rhBMP-2, gel de poloxamer + 3µg rhBMP-2, gel de poloxamer + 7µg rhBMP-2. Los resultados de este estudio mostraron una correlación positiva entre el contenido de calcio y el hueso neoformado.

PRP: A Possibility in Regenerative Therapy / PRP: Una Posibilidad en Terapia Regenerativa

Arecent innovation in dentistry is the preparation and use of platelet-rich plasma (PRP), a concentrated suspension of the growth factors found in platelets. PRP is involved in wound healing and are postulated as promoters of tissue regeneration. This review represents an update of the uses, applications, mechanism of action and clinical benefits of PRP.

Innovaciones recientes en odontología son la preparación y uso de plasma enriquecido de plaquetas (platelet-rich plasma, PRP), una suspensión concentrada de factores de crecimiento presentes en las plaquetas. El PRP está involucrado en la cicatrización y se postula su acción como promotor de la regeneración tisular. Esta revisión corresponde a una actualización de los usos, aplicaciones, mecanismos de acción y beneficios clínicos del PRP.

Morfometría de la parótida de ratón infectado por la cepa RAL de Trypanosoma cruzi en función del sexo / Morphometry of the parotid Gland in mice infected by the RAL strain of Trypanosoma cruzi in function of the sex

Fueron estudiadas las alteraciones y el nivel de deterioro de las parótidas de animales infectados con la cepa RAL de Trypanosoma cruzi. Se utilizaron ratones albinos (Mus musculus) de ambos sexos, debido al dimorfismo sexual de las glándulas salivares, inoculados con 2 x 104 tripomastigotes sanguíneos de la cepa RAL del T. cruzi. Los animales fueron sacrificados al 12° día de infección, coincidiendo con el pico parasitémico. La parótida fue procesada histológicamente y, posteriormente, evaluada histopatológica y morfométricamente. Los resultados permitieron verificar intenso parasitismo en la glándula, la que presentó desorganización estructural y atrofia generalizada de acinos y conductos, más intensos en las hembras. Concluyendo, la cepa RAL del T. cruzi mostró un comportamiento atípico en relación a otras cepas, causando modificaciones más evidentes en las hembras, debido, posiblemente, a alteraciones hormonales desencadenadas por el T. cruzi.

They were studied the alterations and the level of deterioration of the parotid gland in mice infected with the RAL strain oí Trypanosoma cruzi. They were used albino mice (Mus musculus) of both sexes, due to the existence of sexual dimorphism of the salivary glands, inoculated with 2 x 104 blood trypomastigotes of the RAL strain of T cruzi. The animals were sacrificed at the 12th day of infection, coinciding with the parasitemic peak, and the parotid gland was histologically processed and histopathologically and histometrically studied. The results allow verifying intense parasitism in the parotid gland with structural disorganization and widespread atrophy of acini and ducts, more marked in the females. Concluding, the RAL strain of T cruzi shows an atypical behavior in relation to other strains, provoking more clear modifications in the females, probably due to the hormonal alterations motivated by the T cruzi.

Ultrastructure of the adhesion of bacteria to the epithelial cell membrane of three-day postnatal rat tongue mucosa: a transmission and high-resolution scanning electron microscopic study.

Togue mucosa surface of 3-day postnatal rats was examined under transmission electron microscopy (TEM) and high-resolution scanning electron microscopy (HRSEM). For HRSEM analysis, the specimens were fixed in the same solution for 24 h, postfixed in 2% osmiun tetroxide, critical-point dried and coated with platinum-palladium. For TEM analysis, the specimens were fixed using modified Karnovsky solution and embedded in Spurr resin. The results revealed the presence of numerous microplicae in the membrane surface of keratinized epithelial cells to which groups of bacteria were attached. These bacteria were staphylococcus and coccus organized either in rows or at random, which were visualized in three-dimensional HRSEM images. At high magnification, the TEM images revealed the adhesion of bacteria to the cell membrane through numerous filamentous structures comprising the glycocalyx. The fine fibrillar structures rising from each bacterium and from cell membrane were clearly seen. These characteristics on bacteria structure may be used for future control or prevention of bacterial diseases and for installation of the oral native flora.

Ultrastructure of the adhesion of bacteria to the epithelial cell membrane of three-day postnatal rat tongue mucosa: a transmission and high-resolution scanning electron microscopic study

Togue mucosa surface of 3-day postnatal rats was examined under transmission electron microscopy (TEM) and high-resolution scanning electron microscopy (HRSEM). For HRSEM analysis, the specimens were fixed in the same solution for 24 h, postfixed in 2 percent osmiun tetroxide, critical-point dried and coated with platinum-palladium. For TEM analysis, the specimens were fixed using modified Karnovsky solution and embedded in Spurr resin. The results revealed the presence of numerous microplicae in the membrane surface of keratinized epithelial cells to which groups of bacteria were attached. These bacteria were staphylococcus and coccus organized either in rows or at random, which were visualized in three-dimensional HRSEM images. At high magnification, the TEM images revealed the adhesion of bacteria to the cell membrane through numerous filamentous structures comprising the glycocalyx. The fine fibrillar structures rising from each bacterium and from cell membrane were clearly seen. These characteristics on bacteria structure may be used for future control or prevention of bacterial diseases and for installation of the oral native flora.

A superfície lingual de ratos de três dias de idade foi examinada em microscópia eletrônica de transmissão (MET) e em microscópia eletrônica varredura de alta resolução (MEVAR). Para o método de MEVAR, os espécimes foram fixados na mesma solução por 24 h, pós fixados em solução de tetróxido de ósmio a 2 por cento, secos em ponto crítico e cobertos com platina- paládio. Para análise em MET, os espécimes foram fixados utilizando-se solução de Karnovsky modificada e emblocadas em resina Spurr. Os resultados mostraram a presença de numerosas micropregas na membrana superficial das células epiteliais queratinizadas, nas quais estavam aderidos grupos de bactérias. Estas bactérias eram estafilococos e cocos, organizados em fileiras ou a esmo, e puderam ser observadas em imagens tri-dimensionais em MEVAR. Em maiores aumentos, as imagens em MET revelaram a adesão de bactérias nas células por meio de numerosas estruturas filamentares compondo o glicocálice. As delicadas estruturas filamentares na periferia das bactérias e das células foram nitidamente identificadas. Estas características da estrutura bacteriana podem ser utilizadas, no futuro, para controle e prevenção de doenças bacteriana, bem como para a instalação da flora oral nativa.