Morphology, growth and modelling of bone tissue

in Annales de Médecine Vétérinaire (2004), 148(1), 1-13

Bone is an essential part of the squeletton. Besides its mechanic properties, bone has an important role in metabolism regulation because it acts as a reservoir for the storage of minerals essential to ... [more ▼]

Bone is an essential part of the squeletton. Besides its mechanic properties, bone has an important role in metabolism regulation because it acts as a reservoir for the storage of minerals essential to provide homeostasy. This article describes bone morphology and different ways of classification of this tissue. It gives the composition of organic and mineral extracellular bone matrix, underlines the dynamic character of bone tissue, details the cellular morphology and the metabolism of the elements acting on the synthesis/resorption mechanisms : osteoprogenitor cells, osteoblasts, osteocyts and osteoclasts. It relates the histogenesis of bone tissue and develops the different types of ossification: intramembranous, periostic, endochondral and osteonal remodeling. The last part of this article describe some dietetary and hormonal influences on bone tissue. [less ▲]

Morphometric analysis of proposed evolutionary lineages of Early Devonian land plant spores

in Geological Magazine (2005), 142(3), 241-253

Early Devonian miospore assemblages from 'La Gileppe' (Eastern Belgium) include five varieties of trilete spore belonging to the genus Emphanisporites. These five varieties show a continuous variation of ... [more ▼]

Early Devonian miospore assemblages from 'La Gileppe' (Eastern Belgium) include five varieties of trilete spore belonging to the genus Emphanisporites. These five varieties show a continuous variation of their morphological characteristics. The variation in morphological characteristics can be related to the evolution of morphological features and allows us to define the Emphanisporites micromatus Morphon. A statistical evaluation of this population highlights the interdependence of almost all morphological parameters. This study proves the increase in size of ornamental and structural parameters over several million years. The biometric changes and the progressive replacement of older morphotypes by younger ones indicate that a temporal link exists between these different varieties. Two phylogenetic hypotheses for the E. micromatus Morphon are proposed. This morphological evolution is so far observed only on the Eastern Old Red Sandstone Continent and defines a palaeophytogeographic sinuosus-zavallatus Province. [less ▲]

Morphometric and metabolic profile of the distal segment of the internal mammary artery: caution on its use for coronary anastomoses.

in European Journal of Cardio - Thoracic Surgery (1996), 10(11), 965-70

OBJECTIVE: Elastic arteries were found to be less prone to intimal hyperplasia than muscular arteries. The internal mammary artery (IMA), which is elastic in its proximal segment, presents a gradual ... [more ▼]

OBJECTIVE: Elastic arteries were found to be less prone to intimal hyperplasia than muscular arteries. The internal mammary artery (IMA), which is elastic in its proximal segment, presents a gradual decrease of media elastic fibers along its downstream course. Metabolic and morphometric studies of the distal end of the IMA with regard to its local susceptibility to develop intimal changes were undertaken in order to evaluate the reliability of its use as an anastomotic site for bypass grafting. METHODS: Twenty distal segments of IMA were harvested from patients who had undergone myocardial revascularization. Histologic, enzyme-histochemical and morphometric studies were undertaken on these arterial segments. RESULTS: Histologic examinations indicated an elastomuscular structure in 13 patients, a muscular structure in 6 and an elastic structure in 1. Of the 20 IMAs, none was found to have intimal thickening of greater than 25% of the diameter of the lumen. The enzyme-histochemical profile of the proliferating cells found in the intimal thickening differed from normal contractile smooth muscle medial cells in the loss of myosin and mitochondrial ATPase, plasma membrane 5' nucleotidase, moderately decreased aerobic dehydrogenase and increased lactate dehydrogenase activity and ribonucleoprotein-linked pyroninophilia. Lysosomal beta-glucuronidase and sulfatase were strongly active. This enzyme behavior is unfavorable to contractile function and favorable to cell proliferation and lipid accumulation, two events strongly involved in the atherogenic process. CONCLUSION: Intimal proliferative changes were observed in the distal segment of the IMA. Although there was no histologic evidence of atherosclerotic plaque, the enzyme-histochemical profile of this intimal thickening was favorable to cell proliferation and lipid accumulation. These findings suggest that it may be beneficial to avoid coronary anastomoses with the distal end of the IMA and to use a more proximal/elastic segment. [less ▲]

Morphometric study of interphalangeal joints in Ardenner horses with juvenile osteoarthropathy

in Slovenian Veterinary Research (2007), 44

Morphometric Study of the Equine Navicular Bone: Age-Related Changes and Influence of Exercise

in Veterinary Research Communications (1999), 23(1), 15-40

Navicular bones from the four limbs of 95 horses, classified in 9 categories, were studied. The effects of age on navicular bone morphometry and histomorphometry were estimated, after adjustment of the ... [more ▼]

Navicular bones from the four limbs of 95 horses, classified in 9 categories, were studied. The effects of age on navicular bone morphometry and histomorphometry were estimated, after adjustment of the data to even out the effects of front and rear limbs, morphometrical type, sex, weight, and size. All the external measurements of the navicular bone decreased significantly with increasing age. From the histomorphometrical data, cortical bone volume decreased with age in most horses, whereas cancellous bone volume and, in particular, the marrow spaces increased. The increase in the cancellous bone volume could have resulted from tunnelling of the internal part of the cortex, which converted it progressively into a porous trabecular-like structure. Trabecular bone volume also decreased with age and the trabecular lattice changed dramatically to become disconnected in aged horses. These observations corresponded closely to those reported for ageing of the skeletal system in humans. However, in sporting horses, the navicular cortical bone volume increased with age and the cancellous bone volume decreased. Exercise appeared to have decreased bone resorption and increased bone formation at the endocortical junction. The cancellous bone architecture was also improved. in that the trabecular lattice and trabecular bone volume remained unchanged in aged sporting horses. Our findings confirmed that exercise may be good practice to prevent age-related bone loss. [less ▲]

Morphometric Study of the Equine Navicular Bone: Variations with Breeds and Types of Horse and Influence of Exercise

in Journal of Anatomy (1998), 193((Pt 4)), 535-49

Navicular bones from the 4 limbs of 95 horses, classified in 9 categories, were studied. The anatomical bases were established for the morphometry of the navicular bone and its variations according to the ... [more ▼]

Navicular bones from the 4 limbs of 95 horses, classified in 9 categories, were studied. The anatomical bases were established for the morphometry of the navicular bone and its variations according to the category of horse, after corrections were made for front or rear limb, sex, weight, size and age. In ponies, navicular bone measurements were smallest for light ponies and regularly increased with body size, but in horses, navicular bone dimensions were smallest for the athletic halfbred, intermediate for draft horse, thoroughbreds and sedentary halfbreds and largest for heavy halfbreds. The athletic halfbred thus showed reduced bone dimensions when compared with other horse types. Navicular bones from 61 horses were studied histomorphometrically. Light horses and ponies possessed larger amounts of cancellous bone and less cortical bone. Draft horses and heavy ponies showed marked thickening of cortical bone with minimum intracortical porosity, and a decrease in marrow spaces associated with more trabecular bone. Two distinct zones were observed for the flexor surface cortex: an external zone composed mainly of poorly remodelled lamellar bone, disposed in a distoproximal oblique direction, and an internal zone composed mainly of secondary bone, with a lateromedial direction for haversian canals. Flexor cortex external zone tended to be smaller for heavy ponies than for the light ponies. It was the opposite for horses, with the largest amount of external zone registered for draft horses. In athletic horses, we observed an increase in the amount of cortical bone at the expense of cancellous bone which could be the result of reduced resorption and increased formation at the corticoendosteal junction. Cancellous bone was reduced for the athletic horses but the number of trabeculae and their specific surfaces were larger. Increased bone formation and reduced resorption could also account for these differences. [less ▲]

Morphometric study of the stromal vascularization in peritoneal endometriosis.

in Fertility and Sterility (1993), 59(3), 681-4

To evaluate the stromal vascularization of different appearances of peritoneal endometriosis, biopsies were taken from peritoneal areas with endometriosis in a series of 135 infertile women and classified ... [more ▼]

To evaluate the stromal vascularization of different appearances of peritoneal endometriosis, biopsies were taken from peritoneal areas with endometriosis in a series of 135 infertile women and classified as typical (black), red, or white lesions. The number of capillaries per mm2 of stroma, their mean surface area, and the ratio of capillaries/stroma surface area, and the mitotic activity were analyzed in typical, red, and white lesions. Significant differences were found between the different subgroups. The higher vascularization and mitotic activity observed in red lesions suggested the hypothesis that such lesions are very active and probably the first stage of early implantation of endometrial glands and stroma. The poor vascularization and the absence of mitosis observed in white lesions suggested that these lesions are much less active than red lesions and are a quiescent stage of the disease. Our study proves that the "activity" of peritoneal endometriosis is related to the vascularity. This concept must be considered in the further discussion of American Fertility Society Endometriosis Classification. Typical, red and white lesions are three different stages of the peritoneal disease and their relative relation to infertility is also probably different. [less ▲]

Morphometrical study of the equine navicular bone: age-related changes and influence of exercise

in Veterinary Research Communications (1999), 23

Morphométrie du pied du cheval et maladie naviculaire

in Bulletin de l'Académie Vétérinaire de France (1999), 72

Morphométrie Euclidienne des Figures Planes - Application à l'analyse des matériaux granulaires

Doctoral thesis (1993)