959 resultados para Morphological operator


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A morphological and histochemical study of the human vestibular fold was carried out using routine histological techniques. Seven μm-thick histological sections stained with hematoxylin-eosin (HE) and Calleja showed the presence of elastic collagen fibers and seromucous glands in the vestibular fold. Muscle fibers forming the ventricular muscle were also identified. Ultrastructural analyses of the epithelial layer by scanning electron microscopy (SEM) revealed ciliated cells and gland ducts opening on the epithelial surface. Histochemical analyses were performed on ventricular muscles submitted to nicotinamide-adenine-dinucleotide tetrazolium reductase (NADH-TR), succinate dehydrogenase (SDH), and myofibrillar adenosine triphosphatase (mATPase) reactions. Based on these reactions, it was observed that the muscle is formed by three types of muscle fibers: slow-twitch oxidative (SO), fast-twitch oxydative glycolytic (FOG) and fast-twitch glycolytic (FG) fibers distributed in a mosaic pattern. The fiber frequency was 22.7%, 69.9% and 7.4%, respectively. The higher frequency of SO and FOG fibers characterized the muscle as having aerobic metabolism and resistance to fatigue. The ventricular muscle was considered fast. The study of the neuromuscular junctions performed after nonspecific esterase reaction showed that they are of the en-plaque type and have multiple occurrences in the ventricular muscle.

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The evaluation of diversity in germplasm collections is important for both plant breeders and germplasm curators to optimize the use of the variability available. Diversity can be estimated by different genetic markers. The purpose of this study was to estimate the genetic divergence of 30 morphological and agronomic traits in 108 sesame genotypes by multivariate analysis. The Cole-Rodgers index was used to establish the dissimilarity matrices. The principal component analysis identified the traits that contributed most to the divergence and the genotypes were clustered by Tocher's optimization. Despite the narrow genetic basis, the markers were efficient to characterize the genotypes and identify the most similar groups or duplicate and divergent genotypes. Greatest variation was found for the traits number of capsules per plant and grain yield.

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The Phrynops hilarii specie of turtle has its characterization not well defined in the literature, it was proposed in this study the leukocyte characterization of the blood, stained by Leishman and analyzed under light and transmission electron microscope. It was not observe any cellular type with similar characteristics to neutrophils in mammalian group. We believed, based on the data obtained in this study that the heterophils have a morphofuncional analogy with another neutrophils belonged to mammalian group. This conclusion is being supported in many recent studies found in the literature.

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Background: Tacrolimus, an immunosuppressive drug used in organ transplantation, has been reported not to induce gingival overgrowth. However, prevalence studies are limited, and the methods used for assessing gingival overgrowth varies among studies. Objective: The purpose of this study was to evaluate the effects of up to 240 days of tacrolimus therapy on gingival tissues of rats. Materials and methods: Rats were treated for 60, 120, 180 and 240 days with daily subcutaneous injections of 1 mg/kg body weight of tacrolimus. After histological processing, the oral and connective tissue, volume densities of fibroblasts (Vf), collagen fibers (Vcf) and other structures (Vo) were assessed in the region of the lower first molar. Results: After 60 and 120 days of treatment with tacrolimus, gingival overgrowth was not observed. The gingival epithelium, connective tissue, as well as the values for Vf, Vcf, and Vo were similar to those of the control rats (P > 0.05). After 180 and 240 days of the treatment, gingival overgrowth was associated with a significant increase in the gingival epithelium and connective tissue as well as an increase in the V f and Vcf (P < 0.05). Conclusions: Within the limits of the experimental study, it may be concluded that the deleterious side effects of tacrolimus on the gingival tissues of rats may be time-related. © 2007 Blackwell Munksgaard All rights reserved.

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Fertility in female mammals may be affected by a variety of endocrine disrupters present in the environment. Herbicide atrazine is an example of endocrine disrupter employed in agriculture, which disrupts estrous cyclicity in rats. Aiming to characterize morphologically the effect of low and sublethal doses of atrazine on the ovaries of Wistar rats, in an effort to determine the possible intrafollicular target site through which this herbicide acts adult females were submitted to both subacute and subchronic treatments. Additionally, immunocytochemical labeling of 90 kDa heat shock protein (HSP90) was performed in order to evaluate the role played by this protein in the ovary, under stressed conditions induced by herbicide exposure. The results indicated that atrazine induced impaired folliculogenesis, increased follicular atresia and HSP90 depletion in female rats submitted to subacute treatment, while the subchronic treatment with low dose of atrazine could compromise the reproductive capacity reflected by the presence of multioocytic follicle and stress-inducible HSP90. © 2007 Elsevier Ltd. All rights reserved.

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Anurans may be brightly colored or completely cryptic. Generally, in the former situation, we are dealing with aposematism, and the latter is an example of camouflage. However, these are only simple views of what such colorations really mean and which defensive strategy is implied. For instance, a brightly colored frog may be part of a mimicry ring, which could be either Batesian, Müllerian, or Browerian. These are only examples of the diversity of color-usage systems as defensive strategies. Unfortunately, reports on the use of colors as defensive mechanisms are widespread in the available literature, and the possible functions are rarely mentioned. Therefore, we reviewed the literature and added new data to this subject. Then, we the use of colors (as defensive mechanism) into categories. Mimicry was divided into the subcategories camouflage, homotypy, and nondeceitful homotypy, and these groups were also subcategorized. Dissuasive coloration was divided into behavioral display of colors, polymorphism, and polyphenism. Aposematism was treated apart, but aposematic colorations may be present in other defensive strategies. Finally, we propose functions and forms of evolution for some color systems in post-metamorphic anurans and hope that this review can be the basis for future research, even on other animal groups. © 2009 L. F. Toledo and C. F. B. Haddad.

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Acetylacetone has been used as a chemical modifier for the synthesis of undoped and Tb3+-doped Y3Al5O12 powders. A systematic investigation concerning its influence on the structural and morphological properties of amorphous and crystallized samples has been carried out. These properties have been comparatively studied by means of X-ray diffraction, infrared spectroscopy, SEM, XAS and SAXS. 27Al NMR and EPR experiments have been performed to complete the study. The combined results have evidenced that acetylacetone promotes organic groups departure during calcination, entailing a better structural organization at lower temperatures compared with unmodified powders. Structuration has been proven to occur at short-scale range until a 600°C heating treatment before being extended by coalescence at higher temperatures. Finally, the presence of acac ligands on the alkoxides leads to a monomer-cluster aggregation process, and thus to a more open network. © 2010 The Royal Society of Chemistry.

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Clypearia is a rare genus of swarm-founding Neotropical wasp whose biology is very little known. Morphological castes differences, condition of ovaries, relative age, and color pattern differences were analyzed in three species of Clypearia. Physiological differences and low morphometric differentiation between queens and workers were present in all species studied, indicating that these species are characterized by physiological caste only. We suggest that caste determination in the three Clypearia species studied is postimaginal. © 2010 Giovanna Tocchini Felippotti et al.

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The aim of this study was to evaluate the incidence as well morphometry of the foramen of Vesalius in human skulls and analyzing their clinical importance. Dry human skulls (n = 80) and with gender distinction were used (40 male and 40 female). The results demonstrates an total incidence of 40%, 13.75% skulls with the bilateral presence of the foramen, 26.25% skulls with the unilateral presence of the foramen, 31.25% skulls with foramen only of the right side, 22.50% skulls with foramen only of the left side, 25% masculine skulls with at least 1 foramen and 52.25% skulls with at least 1 foramen. The morphometry showed an average diameter of 1.457 ± 1.043 mm on the right and 1592 ± 0938 mm to the left. The average distance to the foramen ovale was 1.853 ± 0.303 mm on the right side and 2.464 ± 0.311 mm on the left. It can be concluded that a deepened anatomical study of the foramen of Vesalius collaborates not only for anatomical knowledge of this structure, but also in clinical situations involving this foramen.

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Collagen makes up one third of the total protein in humans, being formed by the connection of three polypeptide chains arranged in a triple helix. This protein has fundamental importance in the formation of extracellular matrix of connective tissue. This study aimed to analyze the structural changes of collagen, which are resulting from inflammatory processes in oral mucosa, and to make the comparative analysis between the histopathology and the Raman spectra. The samples of tissues with inflammatory fibrous hyperplasia (IFH) and normal mucosa (NM) were evaluated by Raman Spectroscopy, hematoxylin-eosin and Massons trichrome stain. The histological analysis in both stains showed differences in collagen fibers, which was presented as thin fibers and arranged in parallel direction in NM and as collagen fibers are thick, mature and not organized, showing that these types of stain show morphological changes of collagen in IFH. The Raman Spectroscopy discriminate the groups of NM and IFH based on vibrational modes of proline, hydroxiproline and CH3, CH2. The histological stains only shows information from morphological data, and can be complemented by Raman spectra. This technique could demonstrate that inflammatory process caused some changes in collagen structure which is related to aminoacids such as proline and hidroxyproline. © 2011 SPIE-OSA.

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Purpose: This in vitro study aimed to evaluate the effect of different fruit juice drinks available in the Brazilian market on smear layer removal and dentinal tubules opening, as well as to verify the effect of toothbrushing subsequently to the juices exposure. Methods: Dentin specimens were prepared and randomly distributed into the control group (distilled water) and twelve types of fruit juice drinks (cashew, orange, mandarin, apple, passion fruit, guava, strawberry, grape, mango, pear, peach, pineapple). The following treatments were applied: immersion or immersion + brushing. After preparation for SEM, photomicrographs were assessed using an index of smear layer removal. Results: No significant differences regarding smear layer removal and dentinal tubules exposure could be observed between the groups after both treatments (Kruskal-Wallis, post-hoc paired comparisons, P>0.05). The control solution and the fruit juice drinks were not able to remove smear layer and to open dentinal tubules. Significant difference between the applied treatments was detected only for the mango juice group (Mann-Whitney, P<0.05). Conclusion: Under the experimental conditions, the different fruit juice drinks did not promote significant alterations on human radicular dentin morphology regardless of the subsequent application of brushing procedures. Copyright: © 2011 Zandim et al.

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Background: This study was undertaken to test the hypothesis that diabetes and pregnancy detrimentally affect the normal function of urethral striated muscles in rats, providing a model for additional studies related to urinary incontinence. The aim of this study was to evaluate morphological alterations in the urethral striated muscles of diabetic pregnant rats. Materials and Methods: Twenty female Wistar rats were distributed into four experimental groups of five rats as follows: virgin, pregnant, diabetic virgin, and diabetic pregnant. Diabetes was induced using streptozotocin administration (40 mg/kg i.v.). The rats were lethally anesthetized, and the urethra and vagina were extracted as a unit. Cryostat sections (6 μm thick) were cut and stained with hematoxylin-eosin, and immunohistochemical procedures were performed and subjected to morphological and semi quantitative analysis. Results: The urethral striated muscle from the diabetic pregnant rats presented with the following variations: thinning and atrophy, disorganization and disruption associated with the colocalization of fast and slow fibers and a steady decrease in the proportion of fast vs slow fibers. Conclusion: Diabetes and pregnancy impair the urethral striated muscle and alter its fiber type distribution. © Copyright G. Marini et al., 2011.

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New comparative data are presented on the reproductive morphology and anatomy of two genera closely related to grasses, Flagellaria and Joinvillea, in which the flowers are superficially similar, especially in stamen morphology. This investigation demonstrates some anatomical differences between the two genera. For example, both genera depart from the 'typical' condition of tepal vasculature (three-traced outer tepals and one-traced inner tepals): in Flagellaria, each tepal receives a single vascular bundle and, in Joinvillea, each tepal is supplied by three vascular bundles. Joinvillea possesses supernumerary carpel bundles, as also found in the related family Ecdeiocoleaceae, but not in Flagellaria or grasses. In the anther, the tapetum degenerates early in Flagellaria, and is relatively persistent in Joinvillea, in which the pollen grains remain closely associated with the tapetum inside the anther locule, indicating a correlation between peripheral pollen (a feature that is common in grasses) and a persistent tapetum. This study highlights the presence of a pollen-tube transmitting tissue (PTTT) or solid style in the gynoecium of Flagellaria, as also in many Poaceae, but not in Joinvillea or Ecdeiocoleaceae. We speculate that the presence of a PTTT could represent one of the factors that facilitated the subsequent evolution of the intimately connected gynoecia that characterize grasses. © 2012 The Linnean Society of London.

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The liver of P. expansa was characterized morphohistologically. To this end, twenty livers from clinically healthy male and female Podocnemis expansa, weighing from 2.0 to 4,5 kg, supplied by the commercial breeder Fazenda Moenda da Serra, in Araguapaz, state of Goiás, Brazil, were analyzed macro-and microscopically. The coelomatic cavity was opened and the topography of the fresh organs was examined visually. After the histological preparation, the slides were stained with Hematoxylin and Eosin (HE), Periodic Acid-Schiff (PAS), Gomori Trichrome, Reticulin and Picrosirius. The liver of P. expansa is a voluminous organ with an approximately rectangular shape and brown coloration, varying from light to dark shades, and is divided into a right lobe, left lobe, and a central portion. The right lobe is the largest of the three portions. The gall bladder is located in a depression in the caudal portion of the right lobe, where the gall duct begins and empties into the duodenum. Histologically, the hepatocytes are arranged in the form of double cords surrounded by winding sinusoidal capillaries. In cross section, they resemble acini containing approximately two to five hepatocytes surrounding a probable central biliary canaliculus. The hepatocytes are polyhedral or pyramidal in shape, of uniform size, with a few central nuclei and others displaced peripherally, and the cytoplasm is little eosinophilic when analyzed by the HE staining technique. The parenchyma is supported by delicate reticular fibers surrounding hepatocytes and sinusoids. The parenchyma and perisinusoidal spaces contain large quantities of melanomacrophages, mainly close to the portal spaces.