Histological evaluation of the response of apical tissues to glass ionomer and zinc oxide eugenol based sealers in dog teeth after root canal treatment

The object of the study was to compare two commercial root canal sealers: Ketac-Endo (a glass ionomer cement) and Fill Canal (a zinc oxide-eugenol cement). A total of 34 root canals from dog premolars with vital pulps were used. After instrumentation, the root canals were sealed with Ketac-Endo and Fill Canal cements using gutta-percha and a lateral condensation technique. After 270 days the animals were sacrificed with an anesthetic overdose and the maxillae and mandibles were removed and fixed in formalin for 48 h. After routine histological processing the sections were stained with hematoxylin-eosin and Mallory trichrome stains. Microscopic analysis revealed that Ketac-Endo cement presented better results than Fill Canal cement.

FTY720 prevents renal T-Cell infiltration after ischemia/reperfusion injury

Ischemia/reperfusion (I/R) injury, a common early feature in renal transplantation, results from both free radical species generation and local inflammatory responses that attract different types of cells. The interaction with infiltrating leukocytes could promote damage and death of resident renal cells contributing to worsening of renal function. It has been shown that depletion of host T cells protects against kidney damage after I/R injury, although the mechanism is not fully understood. FTY720, a synthetic analog of a natural product extracted from Isaria sincclairii has shown modulatory properties in experimental models of autoimmune disease, transplantation, and I/R injury. FTY720 alters lymphocyte responses to chemokine homing signals, thereby decreasing the number of lymphocytes in inflammatory sites. We evaluated renal function in mice at 3, 5, and 7 days after I/R injury in the presence or absence of FTY720 treatment. FTY720 treatment promoted earlier recovery of renal function associated with a lower number of renal-infiltrating lymphocytes. These findings confirm previous results showing a protective effect of FTY720 in I/R injury models.

Uterine leucocyte infiltration after artificial insemination in bitches

In the present study, polymorphonuclear neutrophils (PMN) were enumerated to evaluate acute uterine inflammation after artificial insemination in the bitch. It was concluded that the canine seminal plasma possessed an immunomodulating action. However, the most commonly used extender for freezing canine semen (Tris glucose with egg yolk and glycerol) was a potential inducer of uterine inflammation. (c) 2006 Published by Elsevier B.V.

Analysis of Apical Root Transportation Associated with Protaper Universal F3 and F4 Instruments by Using Digital Subtraction Radiography

Introduction: The aim of this study was to assess the occurrence of apical root transportation after the use of Pro Taper Universal rotary files sizes 3 (F3) and 4 (F4). Methods: Instruments were worked to the apex of the original canal, always by the same operator. Digital subtraction radiography images were produced in buccolingual and mesiodistal projections. A total of 25 radiographs were taken from root canals of human maxillary first molars with curvatures varying from 23-31 degrees. Quantitative data were analyzed by intraclass correlation coefficient and Wilcoxon nonparametric test (P = .05). Results: Buccolingual images revealed a significantly higher degree of apical transportation associated with F4 instruments when compared with F3 instruments in relation to the original canal (Wilcoxon test, P = .007). No significant difference was observed in mesiodistal images (P = .492). Conclusions: F3 instruments should be used with care in curved canals, and F4 instruments should be avoided in apical third preparation of curved canals. (J Endod 2010;36:1052-1055)

Spatial variability of infiltration and its relationship to some physical properties

Water infiltration into soil is one of the basic factors for estimating irrigation intensity according to the plants' requirements; this is aimed at avoiding problems of surface run-off and degradation. The purpose of the present investigation was to determine the spatial variation of infiltration and its relationship to some physical properties of soil by means of geostatistical techniques in Typic Plinthaquult soils having average texture and flat relief. A 113 point mesh was designned, having a regular distance of 10 m between points, samples being taken from 0 to 0.20 meters depth. Sand, silt and clay content, bulk density, macroporosity, microporosity and total porosity were determined. Infiltration tests were carried out in the field by means of a 15 cm diameter ring. Descriptive statistics and geostatistics were used for analysing the data. Infiltration, silt and microporosity data did not fit a normal distribution curve. Infiltration had high variability, having an average 36.03 mm h(-1). Total porosity was 56.73%, this being the only property that did not show spatial dependency. The smallest ranges were observed for bulk density, macroporosity and microporosity, having values of less than 40 m. The smallest degrees of spatial dependence were observed for infiltration, silt and clay, evidence also being shown of the influence of silt and clay on infiltration rate. Contour maps were constructed; fitting them to the semivariogram models, together with studying the correlations, led to establishing relationships between the properties.

Vernalização e corte do terço apical dos bulbos na produção e qualidade de sementes de cebola

The onion (Allium cepa L.) belongs to the family Alliaceae, and the second vegetables in economic importance. It horticultural culture of high relevance, in central-south and in the far south, is highlighting the states of São Paulo, Rio Grande do Sul, Santa Catarina and Parana. The bulbificacion only begins when the combination of the determinants of bulbificacion (photoperiod and temperature) of each cultivar is reached. It Can be grown in tropical regions with the use of vernalization of the bulbs. The objective of this study is to identify the efficiency in the production of seed, onion depending on the cut or not the bulb before the period of vernalization. The analysis of the variables consisted: humidity; number of seeds; mass of seeds for umbel; umbels number; number of seeds for umbel; total number of flowers and of fecundated flowers; number of seeds for capsule; total mass of seeds; emergency percentage; vigor percentage; index of emergency speed and mass of 100 seeds humidity; number of seeds; mass of seeds for umbel; umbels number; number of seeds for umbel; total number of flowers and of fecundated flowers; number of seeds for capsule; total mass of seeds; emergency percentage; vigor percentage; index of emergency speed and mass of 100 seeds, using the cultivars Baia Periforme and Texas Grano. The experimental design was randomized blocks with four replicates, there was 80 plants for replicate, each parcel was conduced with 20 plants distributed in 4 lines of 5 plants with spacing of 20cm between plants and lines which was avaliated the 6 central plants. The seeds production not variated between cultivars Texas Grano e Baia Periforme. The cultivar Texas Grano showed seeds with more physiological quality. The cut or not cut of the bulbs not changed the physiological quality of the seeds. But utilization of whole bulbs resulted more yield of seeds with more flowers number and fertilized flower in Baia Periforme, more value of the total mass of seeds, number of seeds by plant and number and mass of seed by umbel in two cultivars.

Presença de detritos na região apical de dentes de cães apos o preparo biomecánico com ou sem o emprego de substância auxiliar cremosa.

The subject of this work is to observe if the employment of a cream (ENDO-PTC) during the root canal preparation contributes or not to the condensation of debris in the apical region. Twenty root canals of dogs teeth were divided into two experimental groups: in the first one, the biomechanical preparation was carried out up to the n. 50 Kerr file by using irrigation and aspiration with sodium hypochlorite. In the second experimental group the canal negotiation was done in the same way but using a cream (ENDO-PTC) with sodium hypochlorite as a lubrication substance. A final irrigation and aspiration with sodium hypochlorite was also done in this group. The animal was killed and the pieces prepared for histological analysis. The histological results show us that the employment of a cream during the negotiation of the root canal contributes to a higher condensation of debris in the apical area.

Radiographic and microbiologic evaluation of posttreatment apical and periapical repair of root canals of dogs' teeth with experimentally induced chronic lesion

The objective of the present study was to evaluate radiographically and bacteriologically apical and periapical repair in dogs' teeth with induced chronic periapical lesions with the use of two different operative techniques (techniques 1 and 2). The study was conducted on 40 root canals of upper and lower premolars from two dogs aged approximately 12 months. Periapical lesions were induced by leaving the root canals exposed to the oral environment for 5 days and then sealing them with zinc oxide-eugenol for 45 days. After this period, radiographic examination revealed the occurrence of a radiolucent lesion and endodontic treatment was started. The two techniques did not differ in terms of chemomechanical preparation, final filling, or type of cement, but differed in terms of irrigating solution and the presence of an antibacterial dressing. Thus 4% to 6% hypochlorite and hydrogen peroxide (10 volumes) were used in technique 1 during chemomechanical preparation and an antibacterial dressing based on calcium hydroxide was applied between sessions, whereas Dakin's fluid (0.5% sodium hypochlorite solution) and a final filling with no antibacterial dressing were used in technique 2. After chemomechanical preparation, the root canals were filled with gutta-percha cones and Sealapex (Sealapex-Sybron, Kerr, Sao Paulo, Brazil), and the animals were killed 270 days after the final filling. Blocks were cut into 6-μm sections and stained by the Brown and Brenn method. Radiographic, histomicrobiologic and statistical analysis permitted us to conclude the following: radiographically there was a marked reduction or even the disappearance of the radiolucent area present before treatment with greater success in the group treated with technique 1 (group I) than in the group treated with technique 2 (group II); the extent of bacterial invasion of dentinal tubules was greater and more intense in group II than in group I; and the amount of microorganisms detected in the ramifications of the apical delta and in the lumen of the root canal was intense in group II and mild or absent in group I. © 1994.