972 resultados para Morphometric


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Buffalo ovaries were collected from a slaughterhouse (Frigol, Brazil) and transported to the laboratory in saline solution at 36 degrees C. The ovaries were dissected to realize the evaluations (weight, length, width and height of the ovary; corpus luteum and dominant follicle diameters). The Cumulus-oocyte complexes (COCs) were recovered by aspiration of 2-8 mm follicles. Selected COCs were matured in TCM 199 supplemented with 10% fetal bovine serum, sodium pyruvate, LH, FSH, estradiol and gentamicin. In vitro maturation was carried out at 38.5 degrees C for 22-24 h and 34-36 h. For the evaluation of the nuclear maturation the oocytes were placed in TCM 199 medium added with type v hialuronidase where the granulosa cells were extracted. The denuded oocytes were transferred to 10 mu l of Hoescht 33342 and the chromosomic configuration was evaluated. The oocytes were classified according to meiosis stage in: Germinal Vesicle, Germinal Vesicle Breakdown, Metaphase I, Metaphase II and Degenerated. The means of weight, length, width and height of the ovary were 3.83 g, 2.27 cm, 1.08 cm and 1.56 cm, respectively. The means of corpus luteum and dominant follicle diameters were 1.40 cm and 7.77 mm. The proportion of oocytes that reached metaphase II stage was: 36.68%.

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The maintenance of the avulsed teeth in appropriate media for preserving the cellular viability has been important for repairing the periodontal ligament and preventing the root resorption after tooth reimplantation. Propolis is a substance capable of preserving cellular viability. This study aimed to analyze the propolis substance as a storage media for maintaining the avulsed teeth, besides to determine the ideal time period for keeping the tooth inside it. Thus, 60 maxillary right central incisors of rats were extracted and divided into five groups. In groups I and II, teeth were kept in propolis for 60 min and 6 h, respectively; in group III, teeth were kept in milk for 6 h; in group IV, teeth were kept dry for 60 min; and in group V, they were immediately reimplanted. All teeth had their root canals filled with calcium hydroxide paste. Following, teeth were reimplanted in their sockets. After 15 and 60 days, animals were killed and the obtained samples were processed in laboratory for microscopic and morphometric analyzing. The results showed that the occurrence of inflammatory resorption, dental ankylosis and the formation of the connective tissue parallel to the root surface were similar among groups. It could be verified a greater occurrence of replacement resorption in group IV when comparing to other groups. In groups I and IV, the presence of periodontal ligament-like connective tissue was substantially smaller than the other groups. Regarding to the cementum amount over the root, it could be observed that this was present in smaller amount in groups I and IV. Group II was similar to groups III and IV. Therefore, according to the results of this study, the use of propolis as a storage media for maintaining avulsed teeth could be highlighted, and the 6-h period was more appropriate than the 60-min period.

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Furcation involvement in periodontal disease has been a challenge for the dentist. Objective: The aim of this study was to investigate root dimensions in the furcation area of 233 mandibular first molars. Material and Methods: Digital photomicrographs were used to obtain the following measurements on the buccal and lingual surfaces of each tooth: root trunk height (RT), horizontal interadicular distance obtained 1 mm (D1) and 2 mm (D2) below the fornix and interadicular angle (IA). Results: Mean standard deviation of buccal and lingual furcation measurements were, respectively, 1.37 +/- 0.78 mm and 2.04 +/- 0.89 mm for RT; 0.86 +/- 0.39 mm and 0.71 +/- 0.42 mm for D1; 1.50 +/- 0.48 mm and 1.38 +/- 0.48 mm for D2; 41.68 +/- 13.20 degrees and 37.78 +/- 13.18 degrees for IA. Statistically significant differences were found between all measured parameters for buccal and lingual sides (p<0.05, paired t test). Conclusions: In conclusion, the lingual furcation of mandibular first molars presented narrower entrance and longer root trunk than the buccal furcation, suggesting more limitation for instrumentation and worse prognosis to lingual furcation involvements in comparison to buccal lesions.

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Objectives: The aim of this study was to compare two methods for the evaluation of periapical lesion changes following endodontic therapy (digital subtraction technique and morphometric analysis) by outlining the radiolucent area.Methods: 13 human anterior teeth with pulp necrosis and chronic periapical lesions were used. Periapical radiographs were taken immediately after endodontic therapy (0) and then 2 months, 4 months and 6 months post treatment, using an intraoral radiographic film holder stabilized with impression material. The films were processed in a standard manner and the digitized images were submitted to digital subtraction using Adobe Photoshop 6.0. New bone formation or bone resorption areas were then measured. In the morphometric analysis, the periapical lesions were outlined using VixWin 2000 and the area (in square millimetres) was recorded. The obtained data were submitted to agreement analysis for comparison of the two techniques.Results: There was no correlation between the areas of radiographic changes detected by digital subtraction and periapical lesion outline (r=0.02-0.45). The new bone formation areas observed by digital subtraction presented higher values, with bone changes being especially evident in the 2 month follow-up radiographs, which suggests a higher sensitivity for this method.Conclusions: Both methods are suitable for the evaluation of periapical lesion changes, but the digital subtraction technique is more sensitive for detecting radiographic periapical changes. Dentomaxillofacial Radiology (2009) 38, 438-444. doi: 10.1259/dmfr/53304677

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The aim of this study was to perform a morphometric analysis of the various parts of the intestine of the domestic quail. Twenty-four female quails (Coturnix coturnix japonica) aged 37 weeks were used and accommodated in laying cages for 12 weeks. Each group was fed a standardized diet containing different quantities of calcium: 2.0%, 2.5%. 3.0% and 3.5%. The birds were weighed, killed, and samples of 1 cm were collected from the duodenum, jejunum and ileum and submitted to the histological routine. The sections obtained were stained in haematoxylin & eosin (H&E). For morphometric analysis, 30 villi and 30 crypts of each segment of the small intestine were measured in order to determine the height and area of the villi, as well as the depth of the crypts. The results showed that although the integrity of the gastrointestinal tract was maintained in all the birds treated with the different calcium levels, a calcium level of 3.0% showed the most promise, as the levels of 2.0% and 2.5% did not cause any alteration in the intestinal tract. Furthermore, a calcium level of 3.5% led to a significant reduction in the height of the villosities, and in consequence reduced the digestive and absorptive capabilities.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The morphological and structural alterations that occur in the neuromuscular junctions of the denervated rat diaphragm were studied. Fifteen adult male albino rats (Rattus norvegicus) aged about 60 days and with a mean weight of 200 g were used. Chronically denervated diaphragms were obtained and the animals were sacrificed after 4, 8 and 12 weeks of denervation. The left antimere of the diaphragm was denervated by section of the phrenic nerve and the right antimere was used as control. Each antimere was divided into three fragments: one was used for histochemical (nonspecific esterase) and morphometric study of neuromuscular junctions, and the other two were used for transmission and scanning electron microscopy (SEM) analysis. Histochemical analysis of the diaphragm neuromuscular junctions after denervation showed only small changes in junction morphology. However, these junctions became smaller and elongated and presented less visible contours with increasing time of denervation. Ultrastructural analysis of neuromuscular junctions after 12 weeks showed more or less organized junctional folds on the muscle fiber surface. The junctional cytoplasm exhibited important alterations such as mitochondrial degeneration and the presence of numerous filaments. SEM revealed the presence of deep primary synaptic grooves with peripheral excavations which housed the nerve terminal boutons and exhibited internally the secondary synaptic clefts present among the junctional folds of the sarcolemma. This study showed that some of the morphological changes demonstrated in other denervated striated skeletal muscles are not repeated at the same intensity or in the same temporal pattern in the rat diaphragm.

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The ultrastructural characteristics and the morphometric evaluation of the different types of neurons present in the dorsal root ganglia (DRG) of the South American opossum (Didelphis albiventris) were studied. Four adult male animals were used and the neurons from cervical and lumbar DRG were removed and processed for histological and transmission electron microscopy observations. The morphometric data were obtained from serial sections stained by H/E and Masson's trichrome. The number of neurons in cervical and lumbar DRG was 22 300 and 31 000, respectively. About 68% of the cervical neurons and 62.5% of the lumbar neurons presented areas up to 1300 mu m(2) and were considered as the small neurons of the DRG. The ultrastructural observations revealed two morphological types of neurons: clear large neurons and dark small neurons. The nuclei of both cell types are spherical and the chromatin is disperse and rarefected. The cytoplasm of the dark small neuron is more electron dense and shows a regular distribution of small mitochondria and many rough reticulum cisterns in the periphery. A small Golgi apparatus was close to the nucleus and many disperse neurofilaments occupy most parts of the cytoplasm. Smooth reticulum cisterns are rare and lipofucsin-like inclusions are present at some points. In the clear large neurons, the organelles are homogenously scattered through the cytoplasm. The neurofilaments are close packed forming bundles and small mitochondria and rough reticulum cisterns are disperse. Lipofucsin-like inclusions are more frequent in these cells.

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Muscle growth in Nile tilapia (Oreochromis niloticus) was studied focusing on histochemical, ultrastructural, and morphometric characteristics of muscle fibers. Based on body length (cm), we studied four groups: G1 = 1.36+/-0.09, G2 = 3.38+/-0.44, G3 = 8.90+/-1.47, and G4 = 28.30+/-3.29 (mean+/-S.D.). All groups showed intense reaction to NADH-TR in subdermal fibers and weak or no reaction in deep layer fibers. In G3 and G4, an intermediate layer was also observed with fibers presenting weak reaction; in G4, groups of fibers with intense reaction were observed in the subdermal region. The myosin ATPase (m-ATPase) activities were acid-stable and alkali-labile in subdermal fibers; most deep layer fibers were alkali-stable and acid-labile. Intermediate fibers were acid-labile and alkali-stable. Two fiber populations were observed near deep muscle layer: one large presenting weak acid- and alkali-stable and the other small alkali-stable.During growth, muscle fiber hypertrophy was more evident in intermediate and white fibers for G3 and G4. However, in these groups, the presence of fiber diameters less than or equal to21 mum suggested that there is still substantial fiber recruitment, confirmed by ultrastructural study, but hypertrophy is the main mechanism contributing to increase in muscular mass. (C) 2003 Elsevier B.V. Ltd. All rights reserved.

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Histochemical, ultrastructural and morphometric methods were used to study growth patterns of red, pink and white muscle fibres and their relation to body weight and total length in the fast-growing freshwater fish Piaractus mesopotamicus Holmberg. The correlations amongst body weight, body length and diameter of red, pink and white fibres were low. From 10-15 to 40 50 cm, body weight increased 102.7 times, while the diameter of each type of fibro increased by factors of 0.94, 0.74 and 0.70, respectively. Muscle fibres revealed different morphological and histochemical stages of maturation. The frequencies of < 20 mu-m fibres of red, pink and white muscle tissue in the youngest and oldest classes were 64.5 and 11.0, 38.2 and 7.7 and 24.0 and 1.4%, respectively. In 30-40 cm fish, the frequency of < 20 mu-m fibres in the red and pink tissue was 24.5 and 25.5%, while in the white tissue it was 11.5%. During sexual maturity (40-50 cm), the recruitment of < 20 pm fibres in white muscle was 1.4%. Muscle fibres of this species showed continuous growth by both hyperplastic and hypertrophic mechanisms, and hyperplasia was particularly active in the juvenile phase.