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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Confiabilidade das determinaÃÃes de localizadores eletrÃnicos foraminais: estudos ex vivo e in vivo / Determination of the reliability of electronic foramen locators: ex vivo and in vivo studies

Bruno Carvalho de Vasconcelos 23 September 2011 (has links)
nÃo hà / Os localizadores eletrÃnicos foraminais (LEFs) disponÃveis atualmente utilizam diversos mÃtodos de determinaÃÃo eletrÃnica da posiÃÃo foraminal, qual seja a medida entre o forame apical e uma referÃncia incisal/oclusal, definindo consequentemente o comprimento do canal radicular. Cada um desses mÃtodos procura oferecer maior precisÃo e menor sensibilidade a possÃveis interferÃncias no sistema de canais radiculares. Desta forma, procurou-se avaliar a precisÃo de alguns destes LEFs ex vivo e in vivo na realizaÃÃo de odontometrias eletrÃnicas em diferentes posiÃÃes (0,0 mm e -1,0 mm) e em condiÃÃes de uso clÃnico, respectivamente. No estudo ex vivo, 42 prÃ-molares inferiores tiveram seus comprimentos reais comparados a odontometrias eletrÃnicas realizadas com os LEFs Root ZX, Mini Apex Locator, Propex II, iPex e RomiApex A-15. Inicialmente, em funÃÃo dos displays dos aparelhos, determinaram-se mediÃÃes 1,0 mm aquÃm do forame apical (FA), e posteriormente as mediÃÃes no FA. Para o estudo in vivo, dez pacientes que apresentavam prÃ-molares com indicaÃÃo de exodontia como parte de seus planejamentos clÃnicos ortodÃnticos tiveram odontometrias eletrÃnicas realizadas com os LEFs Propex II e Root ZX previamente a exodontia. Os Ãltimos instrumentos utilizados foram fixados aos dentes que foram entÃo extraÃdos e tiveram 4,0 mm apicais de suas raÃzes expostos e analisados quanto à distÃncia entre as pontas dos instrumentos e os FA. No estudo ex vivo, considerando as mediÃÃes realizadas por cada um dos aparelhos a 0,0 mm e a -1,0 mm, a precisÃo dos LEFs foi: 70,6% e 47,1% (Root ZX), 61,8% e 52,9% (Mini Apex Locator), e 67,6% e 38,2% (Propex II), 61,8% e 38,2% (iPex), e 73,5% e 38,2% (RomiApex A-15), respectivamente (Â0,5 mm). DiferenÃas estatÃsticas foram encontradas para o Propex II, iPex e RomiApex A-15, quando comparadas suas leituras nas duas posiÃÃes (0,0mm X -1,0 mm). NÃo foram encontradas diferenÃas entre os LEFs a 0,0 mm, porÃm, a -1,0 mm o iPex foi estatisticamente inferior aos demais. Jà no estudo in vivo, o FA foi localizado em 75% (Root ZX) e 66,7% (Propex II), considerando margem de Â0,5 mm, tendo sido encontrada diferenÃa estatisticamente significante entre os LEFs. Diante do exposto, nas condiÃÃes do estudo, pode-se concluir que os LEFs sÃo ferramentas confiÃveis na determinaÃÃo de comprimentos reais, todavia, nÃo sÃo infalÃveis; que em condiÃÃes ex vivo, quando mantidos aquÃm do FA, todos os LEFs reduziram sua precisÃo, tendo o Propex II, iPex e RomiApex A-15 apresentado diferenÃas significantes; e que em condiÃÃes de uso clÃnico, o Root ZX apresentou maior confiabilidade do que o Propex II. / The electronic foramen locators (EFLs) currently available are based on different methods for determination of the distance between the apical foramen and a coronal reference, consequently presenting the real root canal length. Each of these methods aim to offer greater precision while presenting lower sensitivity to potential interferences found in the root canal system. With this in mind, the goal of this work was to evaluate the precision of some of these EFLs ex vivo and in vivo for electronic measurement of the root canal length at two different positions (0.0 mm and -1.0 mm) and under clinical conditions, respectively. In the ex vivo study, 42 mandibular bicuspids had their actual lengths compared to electronic measurements performed by the following EFLs: Root ZX, Mini Apex Locator, Propex II, iPex, and RomiApex A-15. Initial measurements were performed to positions identified by the devices as 1.0 mm short of the apical foramen (AF), and subsequent measurements were at the AF (0.0 mm). For the in vivo study, ten patients with bicuspids referred for extraction as part of their orthodontic clinical planning had electronic root length measurements using two EFLs, Propex II and Root ZX, prior to extraction. The last files used were fixated to the teeth, which were then extracted. Then, the apical 4 mm of the canals were exposed to allow assessment of the distance between the tip of the file and the AF. The percentages of precision from the ex vivo electronic measurements at 0.0 mm and -1.0 mm considering each device were: 70.6% and 47.1% (Root ZX); 61.8% and 52.9% (Mini Apex Locator); 67.6% and 38.2% (Propex II); 61.8% and 38.2% (iPex); and 73.5% and 38.2% (RomiApex A-15), respectively (Â0.5 mm). Statistical differences were observed for Propex II, iPex, and RomiApex A-15 when measurements at both positions were compared (0.0 mm X -1.0 mm). No significant differences between the EFLs were observed at 0. 0 mm. However, at -1.0 mm, the precision of iPex was statistically lower compared with the other devices. Regarding the in vivo study, the AF was located in 75% (Root ZX) and 66.7% of the teeth (Propex II), under a tolerance margin of Â0.5 mm. Statistically significant differences were observed between the two EFLs. Based on the results obtained and considering the conditions of this work, it was concluded that EFLs are reliable tools for determining the real length of the canal, but are not infallible. It was also observed in the ex vivo experiments that all EFLs had decreased precision in measurements with the instruments short of the AF, with significant differences observed between Propex II, iPex, and RomiApex A-15. Moreover, it was concluded that under clinical conditions, Root ZX was more reliable than Propex II.
52

Estudo anatômico das dimensões e do padrão vascular do retalho lateral do braço ampliado distalmente ao epicôndilo lateral / Anatomic study of the dimensions and the vascular pattern of distal part to lateral epicondyle of the extended lateral arm flap

Renato Ribeiro Gonçalves 28 April 2003 (has links)
Foram realizadas dissecções anatômicas de 45 membros superiores de cadáveres, com o objetivo de avaliar as dimensões e o padrão vascular da porção distal ao epicôndilo lateral do retalho lateral do braço. Todos os casos deste estudo eram do sexo masculino, com idade superior a 21 anos. Os casos foram divididos em grupos A, B, e C e submetidos a injeção de contraste diretamente na artéria colateral radial posterior. Nos cadáveres do Grupo A, foi injetado contraste a base de azul de metileno e serviu para avaliar o maior comprimento e largura de pele corada pelo contraste, tendo como local para início das medidas o epicôndilo lateral do úmero. No Grupo B foi utilizada a mesma metodologia do Grupo A, sendo acrescentado para cada cadáver em estudo, uma ficha com os dados antropométricos e serviu para avaliar a extensão de pele corada pelo contraste e correlacioná-la com os dados antropométricos individuais. Nos cadáveres do Grupo C foi utilizado contraste a base de látex e serviu para avaliar o padrão vascular da artéria colateral radial posterior encontrado distalmente ao epicôndilo lateral. Em todos os casos a pele foi corada pelo contraste distalmente ao epicôndilo lateral, com o comprimento variando de 4 cm a 12 cm, com média de 7,5 cm e a largura variando de 3 cm a 10 cm, com média de 6 cm. Houve em todas as dissecções um padrão plexiforme da artéria colateral radial posterior distalmente ao epicôndilo lateral. Ocorreu uma correlação entre os comprimentos do braço e do antebraço e as dimensões da área corada pelo contraste, distalmente ao epicôndilo lateral. O autor conclui que é possível a confecção do retalho lateral do braço na forma ampliada, incluindo a pele da região proximal do antebraço, sendo os limites de 7,5 cm de comprimento por 6 cm de largura, distalmente ao epicôndilo lateral, limites seguros para a confecção deste tipo de retalho. A artéria colateral radial posterior apresenta um padrão arterial plexiforme, distalmente ao epicôndilo lateral do úmero. Existe uma relação direta entre o comprimento do retalho lateral do braço ampliado distalmente ao epicôndilo lateral e os comprimentos do braço e do antebraço / Anatomical dissections of forty-five upper limbs of cadavers were made in order to evaluate the dimensions and the vascular pattern of distal part to lateral epicondyle of lateral arm flap. All cases of this study were male, with more than twenty-one years old. The cases were divided into groups A, B and C and they were submitted to a contrast injection directly on posterior radial collateral artery. Into cadavers of Group A it was injected contrast a basis of methylene blue to evaluate the longest length and width of coloured skin by contrast. The place for beginning of measures was the lateral epicondyle of humerus. In the group B, it was used the same methodology of group A, and a record card with anthropometric data of each cadaver. With them it was possible to evaluate the extension of coloured skin by contrast and correlate it with individual anthropometric data. In the cadavers of group C was used contrast a basis of latex in order to evaluate the vascular pattern of posterior radial collateral artery which was found distally to lateral epicondyle. In all cases the skin was coloured by contrast distally to lateral epicondyle, with the length changing from 4 cm to 12 cm, mean length was 7,5 cm and the width changing from 3 cm to 10 cm, mean width was 6 cm. In all dissections, there was a plexiform pattern of posterior radial collateral artery distally to lateral epicondyle. There was a correlation between the length of forearm and the dimensions of coloured area by contrast distally to lateral epicondyle. The author concluded that it is possible the confection of lateral arm flap in enlarged way, including the skin of proximal region of forearm, distally to lateral epicondyle, with distal limits 7,5 cm of length to 6 cm of width to lateral epicondyle, secure limits for confection of this flap. The posterior radial collateral artery presents a plexiform arterial pattern, distally to lateral epicondyle. There is a direct relation between the length of lateral arm flap enlarged distally to lateral epicondyle and the legths of arm and forearm
53

A behavioral and anatomical examination of the intramodal and intramodal effects of early stimulation history and selective posterior cortical lesions in the rat

Buhrmann, Kristin January 1990 (has links)
The aim of this study was to investigate the intra- and intermodal impact of different kinds of early sensory experience on the development of specific neural/perceptual systems. The manipulations of the rats' early experience involved a combination of early binocular deprivation through dark-rearing, somatosensory restriction through cauterization of mystacial vibrissae, and multimodal enrichment through rearing in a complex environment. Specific lesions to somatosensory (Parl) and visual (Oc2M) cortex in differentially reared animals were included in an attempt to gain further insight into the plasticity surrounding manipulations of early stimulation history. Five tasks were used to assess these effects of early rearing condition in combination with later cortical lesions. Behavioral assessment focused on the ability of the animals to encode, abstract, and remember specific relationships between stimuli within the deprived modality itself, their ability to do so with information presented in other modalities, and on the basic species specific behavior. The only effect found was a main effect for rearing condition. Basically, complex-reared rats were more competent on several of the behavioral tasks than were dark-reared rats. However, this result provided little behavioral support for ideas of modality interdependence. Dendritic proliferation is considered to be a general mechanism supporting behavioral change. The subsequent neuroanatomical assessment focused on dendritic branching of neurons in specific cortical areas thought to be most affected by early environmental manipulations. Animals that were raised in a complex environment, but had experienced early tactile restriction through cauterization of vibrissae, showed significantly more dendritic branching than animals from all other rearing conditions in all cortical areas measured. This finding is consistent with ideas of both intra- and intermodal compensation following damage to an early developing modality, as well as behavioral demand acting as a significant factor in determining the impact of early somatosensory restriction. It is reasonable to assume that anatomical changes should be manifested behaviorally. Suggestions for smaller, more restricted studies, that would be more effective in describing the behavioral impact of early manipulations of the environment, were outlined. / Arts, Faculty of / Psychology, Department of / Graduate
54

A morphological and cytological study of Audouinella porphyrae and A. vaga (Rhodophyta)

Tam, Carol Elizabeth January 1985 (has links)
A comparative study was made between two similar red algal endophytes, Audouinella porphyrae (Drew) Garbary and Audouinella vaga (Drew) Garbary, Hansen et Scagel, (Acrochaetiaceae, Acrochaetiales) and their red algal hosts Porphyra spp. and Pterosiphonia bipinnata, respectively. Both endophytes have axial, stellate chloroplasts with a central pyrenoid and reside in their host's cell walls, producing erect portions outside the host that may bear monosporangia. The endophytes were cultured "free" from their hosts and morphological and cytological features of the free-living forms were compared with field material. Although the two endophytes differ significantly in cell dimensions and branching patterns, the free-living forms do not retain these differences. Cell dimensions, branching patterns and developmental patterns are identical in the two free-living forms. Asexual reproduction with regeneration by monospores was observed. Sexual reproduction was not observed in either endophytic or free-living forms of the endophytes. Free-living forms were used for re-infection and cross-infection experiments. Under all experimental conditions, the endophytes showed only epiphytic growth. The hosts seem to have some effect on both of the endophytes. Epiphytes, Audouinella porphyrae and A. vaga were not selective and grew on both hosts, Porphyra torta and Pterosiphonia bipinnata. Both epiphtyes growing on blades of Porphyra tended to branch and have more extensive prostrate portions (3-5 cells) whereas both epiphytes on Pterosiphoni a bipinnata tend not to branch and have only 1-2 cells in the prostrate portions. Ultrastructural studies of both endophytes showed typical florideophycean features. Ultrastructural features of field material of the two endophytes were similar and free-living, cultured endophytes were similar to field material. A large vacuole was observed in sections of the field material of both prostrate and erect portions whereas this was not observed in cultured material. Based on the results of this study it is proposed that the two endophytes are conspecific. Audouinella vaga is referred to synonymy in Audouinella porphyrae (Drew) Garbary, Hansen et Scagel. / Science, Faculty of / Botany, Department of / Graduate
55

The ontogeny of morphological variation : an example from yellow-cedar [Chamaecyparis nootkatensis (D. Don Sprach)]

Banerjee, Satindranath Mishtu January 1990 (has links)
The papers in this thesis represent a series of attempts — empirical and theoretical — to integrate developmental biology with population level studies of variation; to initiate a "developmental population biology" which would complement the well established fields of population ecology and population genetics. The introductory chapter traces the development of the conceptual ideas from the context of the maturation of a single research group. There follow three empirical chapters based on population studies of yellow cedar (Chamaecyparis nootkatensis). The first of these chapters examines the interdependency of progeny growth variation on parentage and stand structure and argues that parentage, developmental history and environmental contingencies can interact in complex ways to structure the variation observed in natural stands. The second chapter examines time related changes in patterns of variation for mainstem growth and needle initiation data of seedlings, and finds that the majority of the increase in variation with time results from differentiation among individual seedlings. The third chapter examines the nature of intra-individual variation in needle (from seedlings) and scale (from mature trees) data from the perspective of the concept of morphological integration, the amount and structure of covariation within an individual. The results of this chapter demonstrate that the nature of morphological integration changes during the course of development, and that variation in morphological integration — that is the pattern of variable relationships or covariance structure — distinguishes individuals. The final chapter is more theoretically oriented, and demonstrates how the patterns of increasing variation with time, and changing covariation with development (Chapters 2, 3) may be unified and explained in the context of developmental trajectories, where such trajectories represent the development of the form of individual organs through time in terms of point trajectories through a multivariate space. The nature of such developmental trajectories is ultimately a manifestation of cell division and elongation in various planes, resulting in the external form of the organs. Three increasingly complex graphical models of developmental trajectories are presented and it is argued that when developmental trajectories diverge from each other in a nonlinear manner, changes can occur in both correlation and covariance structures, coincident with changes in size. The relation between developmental trajectories and the production of variation within populations is further elaborated from the context of dynamical systems theory. / Science, Faculty of / Botany, Department of / Graduate
56

The rat ovarian surface epithelium in vitro

Adams, Anne Theresa January 1982 (has links)
The ovarian surface epithelium, a very small portion of the total mass of the ovary, is generally thought to be the site of origin of over 85% of ovarian cancers. Such cancers are classified with the "Common Epithelial Tumours" of the ovary. In most industrialized countries, malignancies of the ovary rank fourth in cancer deaths in women; over 70% of these neoplasms have spread beyond the ovary when first diagnosed. Experimental approaches to the study of carcinogenesis in this tissue have been limited by the lack of pure populations of ovarian surface epithelial cells. Studies done on rodents in vivo suggest that both chemicals and C-type RNA viruses can induce ovarian cancers similar to those which are said to arise from the surface epithelium. However, the cell of origin cannot be proven in such studies. The purpose of this project was to develop a model for ovarian cancers of surface epithelial origin based on-carcinogenesis in vitro. To this end a method was devised to culture the rat ovarian surface epithelium in pure form. These cultured cells, whose identity has been confirmed by morphological, histochemical and ultrastructural means, are polygonal with clear cytoplasm, have well-defined borders, and grow in confluent monolayers. Their morphology is quite distinct from those of other ovarian cells in vitro. Cultured rat ovarian surface epithelial cells are histochemically positive for 17β-hydroxysteroid dehydrogenase, and negative for Δ5-3β-hydroxysteroid dehydrogenase, the same as in frozen sections of whole rat ovary. Ultrastructurally, cultured surface epithelial cells have basal laminae, microvilli, apical intercellular junctions, large nuclei, abundant rough endoplasmic reticulum, Golgi complexes, perinuclear bundles of microfilaments, and numerous vesicles. Although the ovarian suface epithelium is suspected of being an estrogen target tissue, there is no previous report of estrogen receptors in these cells. In this study cultured rat ovarian surface epithelial cells have been shown by autoradiographic means to exhibit estrogen receptor-like activity. Translocation of tritiated estradiol from cytoplasm to nucleus, and estrogen-specific binding have been demonstrated. Estradiol was shown to be mitogenic for cultured ovarian surface epithelial cells. From these results, the surface epithelial .cells of the ovary should be considered an estrogen target tissue. Kirsten murine sarcoma virus was used to produce three transformed cell lines from pure, first passage cultures of these cells. These three lines retained 170-hydroxysteroid dehydrogenase activity and showed slight Δ5-3β-hydroxysteroid dehydrogenase activity. Tumours resulting when these cells were injected into immunosuppressed female rats were highly malignant and resembled histologically human endometrioid stromal sarcomas of the ovary. This neoplasm is classed with the "Common Epithelial Tumours" of the ovary, but is generally not considered a derivative of the surface epithelium. In light of this study, perhaps this tumour should: be considered, to be of surface epithelial origin. A continuous cell line arising from pure cultures of rat ovarian surface epithelial cells produced structures in vitro resembling those found in ovarian serous papillary cystadenomas of borderline malignancy. This tumour is classed as a common epithelial ovarian tumour. Hence, in this study the rat ovarian surface epithelium has been cultured in pure form, has been characterized for a number of properties by several investigative techniques, and has been shown to be susceptible to transformation by an oncogenic virus; This work supports the theory that the "Common Epithelial Tumours" of the ovary are, in fact, derived from the surface epithelium. The availability of cultured ovarian surface epithelial cells should allow investigation into factors which make this tissue so susceptible to malignant transformation. From such cultures could come markers suitable for use in tests to detect ovarian cancers at an early stage. The culture of pure rat ovarian surface epithelium, as described herein, could readily be used to study chemical, physical and viral carcinogenesis in this tissue to produce experimental models of cancers arising in the ovarian surface epithelium. / Science, Faculty of / Zoology, Department of / Graduate
57

Neuron-glial interactions in dendrite growth

Le Roux, Peter David January 1995 (has links)
Interactions between neurons and glia occupy a central role in many aspects of development, maintenance, and function of the central nervous system (CNS). A fundamental event in CNS development is the elaboration of two distinct neuronal processes, axons and dendrites. The overall aim of this research was to characterize the interactions between central nervous system neurons and astroglial cells that regulate dendrite growth from cerebral cortical neurons. Embryonic (E18) mouse cerebral cortical neurons were cocultured with early postnatal (P4) rat astroglia derived from cerebral cortex, retina, olfactory bulb, mesencephalon, striatum and spinal cord. Axon and dendrite outgrowth from isolated neurons was quantified using morphological and double-labeling immunohistochemical techniques at 18 hours and 1, 3 and 5 days in vitro. Neurons initially extended the same number of neurites, regardless of the source of glial monolayer; however, astroglial cells differed in their ability to maintain primary dendrites. Homotypic cortical astroglia maintained the greatest number of primary dendrites. Astroglia derived from the olfactory bulb and retina maintained intermediate numbers of dendrites, whereas only a small number of primary dendrites were maintained by astroglia derived from striatum, spinal cord or mesencephalon. Initially longer axons were observed from neurons grown on astroglia that did not maintain dendrite number. After 5 days in vitro, axon growth was similar on the various monolayers, total primary dendrite outgrowth, however, was nearly threefold greater on astroglia derived from the cortex, retina and olfactory bulb than on astroglia derived from mesencephalon, striatum or spinal cord. This effect was principally on the number of primary dendrites rather than the elongation of individual dendrites and was independent of neuron survival. Similar morphological differences were observed after 5 days in vitro when cortical neurons were grown on polylysine in either a noncontact coculture system where astroglia continuously conditioned the culture medium or in astroglial conditioned medium. Preliminary biochemical analysis of the medium conditioned by cortical astroglia using heat and trypsin degradation, ultracentrifugation, dialysis, and heparin affinity chromatography suggested that a heparin binding protein with a molecular weight between 10 and 100kDa may be responsible for astroglial mediated dendrite growth. Neurons that were grown in medium conditioned by either mesencephalic or cortical astroglia for the first 24 hours followed by culture medium from astroglia of the alternate source for 4 days in vitro, confirmed that astroglia maintained, rather than initiated, the outgrowth of the primary dendritic arbor. In the next series of experiments, E18 mouse cortical neurons were cocultured with neonatal (P4) or mature (P12) rat astroglia derived from cortex and mesencephalon or astroglia derived from P4 and P12 lesioned cortex. After 5 days in vitro, the maturational age of astroglia did not appear to alter the extent of primary dendrite growth; instead dendrite growth reflected the region of the CNS from which the astroglia were derived. By contrast, a reduced ability to support axon growth from mouse cortical neurons in culture was observed on astroglia derived from mature rat cortex or mesencephalon. Reactive astroglia demonstrated similar neurite supporting characteristics to mature astroglia and were able to maintain dendrite growth, principally primary dendrite number. Axon elongation, however, was reduced on both neonatal and mature reactive astroglia. Neuron survival did not correlate with the ability of the various astroglia to support process outgrowth. Collectively these results indicate: 1) neuron-glial interactions are critical for the regulation of process outgrowth from embryonic cortical neurons in vitro, 2) axon and dendrite growth appear to be differently controlled by astroglia, 3) CNS astroglia demonstrate regional differences in maintaining, but not initiating growth of the primary dendritic arbor, 4) this effect may be due, in part, to release of a diffusible heparin binding protein factor, and 5) mature and reactive astroglia support primary dendrite, but limited axon growth. We propose therefore that the local astroglial environment maintains primary dendrite growth from neurons until synaptic contacts can be established. A mechanism that maintains the primary dendritic arbor and allows separate regulation of axon and dendrite growth, prior to the arrival of afferents, may be critical for establishing appropriate and specific synaptic connections. These findings have important implications in understanding development and function of the mammalian central nervous system and may lead to novel strategies for intervention in acute and chronic neurological disorders.
58

Basics in paleodemography: a comparison of age indicators applied to the early medieval skeletal sample of Lauchheim

Wittwer-Backofen, U., Buckberry, J., Czarnetzki, A., Doppler, S., Grupe, G., Hotz, G., Kemkes, A., Larsen, C. S., Prince, D., Wahl, J., Fabig, A., Weise, S. January 2008 (has links)
Recent advances in the methods of skeletal age estimation have rekindled interest in their applicability to paleodemography. The current study contributes to the discussion by applying several long established as well as recently developed or refined aging methods to a subsample of 121 adult skeletons from the early medieval cemetery of Lauchheim. The skeletal remains were analyzed by 13 independent observers using a variety of aging techniques (complex method and other multimethod approaches, Transition Analysis, cranial suture closure, auricular surface method, osteon density method, tooth root translucency measurement, and tooth cementum annulation counting). The age ranges and mean age estimations were compared and results indicate that all methods showed smaller age ranges for the younger individuals, but broader age ranges for the older age groups.
59

Estudo da anatomia do nervo tibial e seus ramos ao nível do terço distal da perna / Study of the anatomy of the tibial nerve and its branches at the distal third of the leg

Torres, André Leal Gonçalves 06 June 2011 (has links)
INTRODUÇÃO: Estudos experimentais e clínicos, realizados por diversos autores, demonstraram a susceptibilidade à compressão nervosa periférica na vigência da diabetes mellitus e modificações na evolução natural da doença após descompressões nervosas cirúrgicas dos sítios propícios a constrição neural. Em membros inferiores, a síndrome do túnel do tarso sobreposta às neuropatias vigentes ainda gera conflitos na literatura. A anatomia do nervo tibial e seus ramos ao nível do terço distal da perna e túnel do tarso apresentam variações importantes que não são contempladas nos livros texto e atlas de anatomia. OBJETIVO: Determinar, através de dissecção em cadáveres frescos, a anatomia topográfica do nervo tibial e seus ramos ao nível do tornozelo, em relação ao túnel do tarso. MATERIAL E MÉTODOS: O estudo foi realizado através da dissecção anatômica bilateral de 26 cadáveres frescos. Foi fixada, entre o cento do maléolo medial e o centro do calcâneo, uma linha de referência (eixo maleolar-calcaneal). Com base nesse eixo as localizações da bifurcação do nervo tibial e dos ramos calcâneos mediais e inferiores foram aferidas em milímetros. Para as bifurcações foi estabelecida uma classificação por tipos de I a V, baseada no posicionamento em relação ao túnel do tarso (definido como dois centímetros proximais e distais ao eixo). Para os ramos calcâneos, a quantidade e seus respectivos nervos de origens também foram analisados. Os resultados foram transformados em taxas (porcentagem) e comparados aos achados de outros estudos. RESULTADOS: Vinte e seis cadáveres (50 pernas) foram pesquisados. A bifurcação do nervo tibial ocorreu sob o túnel em 88% dos casos e proximalmente em 12%. Tivemos o tipo I em 52%, tipo II em 14%, tipo III em 22%, tipo IV em 12% e o tipo V não foi visualizado. Quanto ao ramo calcâneo medial encontramos: um (58%), dois (34%) e três (8%), com a origem mais comum ocorrendo do nervo tibial (90%). De um total de 75 ramos calcâneos mediais dissecados, 40 tiveram sua origem fora do túnel proximalmente (53,3%) e os demais dentro. Com referência ao ramo calcâneo inferior, constatou-se a presença de um único ramo por perna, com 92% emergindo sob o retináculo flexor, 4% proximalmente e 4% distalmente a ele. A origem mais comum foi do nervo plantar lateral (70%), seguida do nervo tibial (18%). CONCLUSÕES: 1- A bifurcação do nervo tibial nos ramos plantares medial e lateral ocorreu sob o retináculo flexor em 88% das pernas, localizando-se, em 70% das vezes, em uma área compreendida entre 10 mm proximais e distais ao EMC. 2- O ramo calcâneo medial apresentou grande variação tanto na sua origem e número de ramos quanto na sua localização em relação ao túnel do tarso. A apresentação de um ramo com origem do nervo tibial, no túnel ou proximalmente a ele, foi a mais observada (58%). 3- O ramo calcâneo inferior esteve sempre presente e com certo grau de variação quanto a sua origem. A apresentação de ramo único oriundo do nervo plantar lateral foi a mais constante (70%) / INTRODUCTION: Experimental and clinical studies developed by several authors displayed the susceptibility to peripheral nerve compression in the presence of diabetes mellitus and changes in the natural evolution of the disease after surgical nerve decompressions of the propitious sites of neural constriction. In lower members, the tarsal tunnel syndrome overlapped on neuropathies still generates conflicts in the available literature. The tibial nerve and its branches anatomy at the distal leg level present significant variations that are not contemplated in textbooks and anatomy atlas. OBJECTIVE: Determine through dissection in fresh cadavers, the topographic anatomy of the tibial nerve and its branches at the ankle, in relation to the tarsal tunnel. MATERIAL AND METHODS: The study was accomplished through bilateral anatomical dissection of 26 fresh cadavers. A reference line was fixed between the center of medial malleolus and the center of calcaneus (malleolarcalcaneal axis - MCA). Based on this axis, the locations of the tibial nerve bifurcation and its medial and lower calcaneal branches were measured in millimeters. For the bifurcations, it was established a classification by types I to V, based in positioning related to the tarsal tunnel (defined as two centimeters proximal and distal to the axis). For the calcaneal branches, the amount and their respective nerves of origin were also analyzed. The results were transformed in rates (percentages) and compared with findings of other studies. RESULTS: Twenty six cadavers (50 legs) were investigated. The tibial nerve bifurcation occurred under the tunnel in 88% of the cases and proximally in 12%. The study had the type I in 52%, type II in 14%, type III in 22%, type IV in 12% and type V was not visualized. As for the medial calcaneal branch it was found: one (58%), two (34%) and three (8%), with the most common source occurring in the tibial nerve (90%). A total of 75 medial calcaneal branches dissected, 40 had their origin outside the tunnel proximally (53.3%) and others had within. With reference to the lower calcaneal branch, it was detected the presence of a single branch per leg, with 92% emerging under the flexor retinaculum, 4% proximally and 4% distally to it. The most common origin was the plantar lateral nerve (70%) followed by the tibial nerve (18%). CONCLUSIONS: 1- The bifurcation of the tibial nerve in the medial and lateral plantar branches occurred under the flexor retinaculum in 88% of the legs, locating, 70% of the time, in an area between 10 mm proximal and distal to the MCA. 2- The medial calcaneal branch presented wide variation as much in its origin as in its location in relation to the tarsal tunnel. The presentation of one branch originating from the tibial nerve in the tunnel or proximally to it was the most observed (58%). 3- The lower calcaneal branch was always present and with a certain degree of variation related to its origin. The presentation of a single branch from the lateral plantar nerve was the most constant (70%)
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"Estudo anatômico da distribuição, tamanho e número dos linfonodos mediastinais em brasileiros adultos" / Anatomical study of distribution, size and number of the mediastinal lymph nodes in Brazilian adults

Schmidt Junior, Aurelino Fernandes 13 December 2004 (has links)
Para analisar o número e tamanho dos linfonodos mediastinais, cinqüenta cadáveres de brasileiros adultos foram dissecados de acordo com o mapa de Naruke/ATS-LCSG (1997). Foram retirados 1742 linfonodos, com 2,58±1,89 linfonodos por região, e realizadas suas medidas por processo digital. O tamanho médio da área, eixo maior e menor foi maior na cadeia 7 (195mm2, 18,75mm e 10,92mm) e 4R (115mm2, 13,72mm e 8,30mm), apresentando média de 49,41mm2, 9,40mm e 5,76mm para as demais regiões, respectivamente. A distribuição, número e tamanho dos linfonodos não mudou de acordo com a idade, sexo, raça, peso ou altura, contudo o tamanho aumentou em função da coalescência por processos granulomatosos prévios, com diminuição do número total de linfonodos / To analyze the number and sizes of the lymph nodes in the mediastinum, fifth human adult cadavers were dissected according to the Naruke/ATS-LCSG map (1997). It were removed 1742 lymph nodes, with 2,58±1,89 nodes for each region, and measured by a digital process. The mean area, long and minor axis were larger in regions 7 (195mm2, 18,75mm and 10,92mm) and 4R (115mm2, 13,72mm and 8,30mm), with a mean of 49,41mm2, 9,40mm and 5,76mm in the other regions, respectively. The distribution, number and size of the lymph nodes did not showed changes according age, sex, race, weight or high, however the size increases as function of coalescence by previous granulomatous processes, with decrease of the total number of lymph nodes

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