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PubMed1995

Coronary angiogenesis. From morphometry to molecular biology and back.

We have reviewed briefly the current state of knowledge relating to the regulation of angiogenesis, including the role of angiogenic growth factors, and we have described the major structural components of the vascular wall and their changes during formation of new channels. Finally, we have described quantitative evaluations of vascular growth in cardiac muscle. Examples of substantial angiogenesis during the early postnatal stages of normal development were used together with examples depicting a more moderate stimulation of capillary growth in adult rat hearts treated with nifedipine or thyroxine. Adequate capillary supply is a precondition for tissue survival and proper function. This is probably why vascular growth is so tightly regulated by several systems which may alternately stimulate or inhibit the formation of new vessels. Recent advances in molecular biology have enabled us to study the mechanisms of angiogenesis under both in vitro and in vivo conditions, but the final assessment of vascular growth should be accomplished through morphometric analysis.

Aging↗
PubMed1989

Optic disc morphometry in simple optic nerve atrophy.

This study was undertaken to evaluate the optic disc changes in eyes with non-glaucomatous optic nerve damage. The intra- and parapapillary region was evaluated morphometrically in 106 eyes of 56 patients with simple optic nerve atrophy (SONA) and in 107 normal eyes of 57 subjects. Colour stereo optic disc diapositives were used. Only one randomly chosen eye per subject and patient was taken for statistical analysis. Characteristics of SONA were: decreased visibility of the parapapillary retinal nerve fibers, diminished retinal vessel diameter, and area with pallor larger than area with cupping. Size and form of the optic disc, neuroretinal rim, peripapillary scleral ring, and zone Alpha and Beta of the parapillary chorioretinal atrophy were not significantly different. Also, distinctness of a tesselated fundus, frequency of optic disc haemorrhages and frequency of bared circumlinear or bared cilioretinal vessels did not differ significantly. These morphologic features are helpful in the diagnosis and differential diagnosis of SONA.

Adult↗
PubMed1983

Ultrastructural morphometry of the human sperm flagellum with a stereological analysis of the lengths of the dense fibres.

The dimensions of the various regions of the flagellum and the length of each of the dense fibres has been determined by transmission electron microscopy of a large number of spermatozoa from ten men. The overall mean length of the flagellum was 60.5 micron, and its diameter diminished from 0.88 micron in the midpiece to 0.17 micron at the terminal filament. The midpiece and terminal filament as measured in longitudinal sections had variable lengths among spermatozoa (3.4 +/- 0.5 (S.D.) micron and 3.1 +/- 1.0 micron respectively). Stereological analysis was used to estimate the length of the principal piece (53 micron) and the dense fibres. These latter fibres were of unequal length and extended along 60% of the length of the principal piece. They fell into 3 groups with respect to their lengths: (i) fibres 3 and 8 were short (6 micron); (ii) fibres 4, 2 and 7 were of medium length (17, 18 and 21 micron respectively); and (iii) the longest fibres were 5, 6, 9 (31, 32 and 31 micron respectively) and fibre 1 which was a little longer (35 micron). Although there was variation in the length of the various fibres among spermatozoa, the order of their termination was relatively constant. The relationship between these quantitative data regarding the structural characteristics of the dense fibres and the shape of the flagellar wave is discussed.

Cytoskeleton↗
PubMed1983

Morphometry of fetal Leydig cells in the monkey (Macaca fascicularis), correlation with plasma testosterone.

The evolution of Leydig cells in Macaca fascicularis fetuses was followed throughout gestation (50-150 d) by morphometric procedures (volume densities of: cells, SER, mitochondria and lipid droplets). Testosterone from umbilical artery plasma was radioimmunoassayed starting on day 57. After predifferentiation and differentiation phases, Leydig cells entered the maturity phase (57-66 d), they occupied 19% of testicular volume, SER and lipid droplets represented 19% and 5% respectively of cytoplasmic volume. Then Leydig cells regressed dramatically (involution phase I: 66-83 d), their volume density decreased to 8%, that of SER to 12% whereas lipids doubled. Leydig cell volume density diminished to 5% during the second half of gestation (involution phase II), but their ultrastructure was not significantly altered. High plasma testosterone level (2.4 ng/ml) was observed during the maturity phase of Leydig cells, decline of testosterone occurred during involution phases I and II (1.13 and 0.58 ng/ml respectively). Its was shown that from day 57 to the end of fetal development the evolution of the plasma testosterone level correlated with the Leydig cell volume density and the SER volume density.

Animals↗
PubMed1984

Morphometry of the ultrastructure of the blood-joint barrier in the rabbit knee.

The ultrastructure of the barrier to water and solute exchange between blood and a synovial cavity was studied morphometrically in five rabbit knees. The synovial surface consisted of 80% synoviocytes and 20% interstitium in direct contact with synovial fluid. The surface intercellular gaps were wide (0.1-5.5 microns). A rich network of capillaries lay just beneath the surface, the commonest (modal) depth of the capillary perimeter being 5 microns at its nearest point. Of these capillaries, 91% were fenestrated in adipose synovium, 44% in areolar synovium and 21% in posterior synovium; the remainder were continuous capillaries. The number of fenestrae per fenestrated capillary was low (approximately 0.5 micron-1, circumference: approximately 6 microns-2). The fenestrae (width 52 nm; membrane thickness 3-4 nm) occupied approximately 1% of the fenestrated endothelial surface-area. Nuclear segments and intercellular junctions were roughly twice as frequent in continuous capillaries as in fenestrated capillaries of the same circumference, indicating that continuous endothelial cells are of smaller surface area than fenestrated cells. The basement membranes of continuous and fenestrated synovial capillaries were relatively thick (98 and 110 nm respectively), perhaps supporting the synovial endothelium during joint motion. In both fenestrated and continuous capillaries the nuclei were preferentially oriented away from the synovial surface (92 and 67% respectively), which presumably facilitates exchange with the surface.

Animals↗
PubMed1991

A two-dimensional morphometry-based model of interstitial and transcapillary flow in rabbit synovium.

The synovial lining of a joint is a layer of specialized connective tissue, containing fenestrated capillaries, that regulates the volume and composition of fluid in the joint cavity. The hydraulic conductance of the synovial lining and of the plasma-to-cavity pathway is increased by high intra-articular pressures (IAP greater than 9 cmH2O) and this is accompanied by an increase in the interstitial pathway's area/pathlength ratio. In order to assess the contribution of the altered pathway geometry to the conductance changes, and also to evaluate the conductivity of the synovial interstitial matrix (Ki) and local flow patterns, a two-dimensional model of trans-synovial flow was developed from morphometric data at low IAP (5 cmH2O) and high IAP (25 cmH2O). Darcy's law was applied to finite elements within a 'unit cell' of synovium to compute a steady-state pressure field. Elements adjacent to limited discrete porous regions of the capillary wall were additionally subjected to the Starling principle. Appropriate values of Ki and capillary wall conductance were obtained by iteration to match the experimentally measured net conductances. The value of Ki that matched the data at low IAP was 1.4-2.1 x 10(-12) cm4 s-1 dyn-1 (1.4-2.1 x 10(-15) m4 s-1 N-1). This is in the range reported for some other fluid-confining tissues, namely scleral stroma and aortic wall. Comparison between a capillary model with localized porous regions and one with a uniformly distributed permeability showed that the uniformity assumption (commonly used in mathematical modelling) leads to severe underestimation of the local pericapillary pressure gradients. At high IAP, synovial deformation was found to account for 24-50% of the increased hydraulic conductances. To explain the remainder, it was necessary to postulate a rise in Ki, especially in the zone between the joint cavity and capillary wall. Possible mechanisms involving tissue hydration and/or glycosaminoglycan wash-out at high IAP are discussed. The model highlights a need for quantitative biochemical analysis.

Animals↗
PubMed1992

Endothelial cell morphometry of atherosclerotic lesions and flow profiles at aortic bifurcations in cholesterol fed rabbits.

Observations on shapes of endothelial cells both in sudanophilic and nonsudanophilic regions at bifurcations of the brachiocephalic (BC) and left subclavian (SA) arteries in hyperlipidemic rabbits were performed under a SEM. The stagnation point of flow and leading edges of flow dividers were nonsudanophilic and covered by round and long fusiform endothelial cells, respectively. The hips of flow dividers of both branchings, proven to be relatively low shear stress regions, by movement of microspheres in steady flow, were sudanophilic and covered by ellipsoidal cells. Similar studies were carried out in normolipidemic rabbits. It might be concluded that lipid deposition in hyperlipidemic rabbits occurs in relatively low shear stress regions, where endothelial cells are functionally activated, rather than in laminar high shear stress regions at the flow divider.

Animals↗
PubMed1984

Morphometry of cat's pulmonary arterial tree.

Morphometic data of the pulmonary artery in the cat's right lung are presented. Silicone elastomer casts of cat's right lung were made, and measured, counted and analyzed. The Strahler system is used to describe the branching pattern of the arterial vascular tree. These data are needed for any quantitative approach to the study of the pulmonary circulation. For all the pulmonary blood vessels of the cat lying between the main pulmonary artery and the capillary beds, there are a total of 10 orders of vessels in the right upper lobe, 9 orders of vessels in the right middle lobe and 11 orders of vessels in the right lower lobe. The ratio of the number of branches in successive orders of vessels or the branching ratio, is 3.58. The corresponding average diameter ratio is 1.72, whereas the average length ratio is 1.81.

Animals↗
PubMed2000

Sub-regional tissue morphometry in male athletes and controls using dual X-Ray absorptiometry (DXA).

Athletes have traditionally been evaluated for body composition by percent fat, percent muscle, and somatotype. Since the late 1980s, dual X-ray absorptiometry (DXA) has offered total and regional body composition of bone mineral content (BMC), lean tissue and fat, but studies involving athletes are rare (11) and have not included regional tissue distribution. In the present study, DXA was used to compare a total of 121 male subjects belonging to 9 different athletic groups and controls. ANOVA showed total tissue percent BMC, lean tissue, and fat were significantly different between the various athletic groups (p <.001). Regional differences in tissue distribution between different athletic groups affect BMC and lean tissue (p <.001), but not fat (p >.05). However, athletes of the leanest groups had different fat distribution to that of nonexercising controls (p <.01). It appears that fat distribution is nonspecific in its response to exercise, while lean and BMC distributions show highly specific adaptations to specific sports.

Absorptiometry, Photon↗
PubMed1977

Nuclear morphometry during the cell cycle.

Directly measured and derived geometric and densitometric parameters were obtained by means of the automated image analyzer Quantimet 720-D in Feulgen-stained HeLa cells synchronized by selective mitotic detachment. These data indicate substantial alteration of nuclear morphology during the entire cell cycle, even during the G1 and G2 phases, and the late G1-early S and late S-G2 transitions.

Cell Division↗
PubMed2004

Optic nerve head morphometry in healthy adults using confocal laser scanning tomography.

BACKGROUND/AIMS: To study the optic nerve head (ONH) characteristics in a cross sectional study with confocal laser scanning tomography using the Heidelberg retina tomograph (HRT I) and thereby to obtain a new HRT database for comparison of healthy and glaucomatous eyes. METHODS: White adults with no history of ocular pathology were eligible for the study. The examination comprised: assessment of visual acuity; slit lamp examination of the anterior and posterior segment; Goldmann applanation tonometry; computerised perimetry, and optic nerve head tomography with HRT. Eyes with ocular pathology were excluded. Mean (standard deviation, SD) and difference between right and left eye (RE-LE) were calculated for HRT I measurements. Differences in mean topographic parameters between male and female participants and between the age quartiles were analysed. The study included 1764 eyes of 882 healthy adults (154 females and 728 males, mean age of 46.8 (SD 8.6) years). The population investigated was larger and older in comparison with similar studies using confocal laser scanning tomography. RESULTS: With HRT I, a mean disc area of 1.82 (SD 0.39) mm(2), a mean cup area of 0.44 (SD 0.32) mm(2) and a mean cup:disc area ratio of 0.22 (SD 0.13) was observed. Right eyes showed a larger mean retinal nerve fibre layer thickness (RNFLT) (0.263 (SD 0.066) mm) compared with left eyes (0.252 (SD 0.065) mm, p<0.001). Higher values in younger volunteers (mean age 35.7 years) in comparison with elderly participants (mean age 59.1 years) were noted for disc area (1.84 mm(2)v 1.78 mm2) and mean RNFLT (0.263 (SD 0.06) mm v 0.249 (SD 0.07) mm) but were not significant (p>0.01). The presented results differ from published data on ONH measurements of healthy volunteers with different techniques. CONCLUSION: The observed differences in ONH measurements between left and right eyes seem not to be of clinical importance. This is also true for age or sex dependent changes in ONH topographies. The presented data provide a new basis for comparison of optic disc characteristics between healthy eyes and glaucomatous eyes.

Adult↗
PubMed1978

Metacarpal morphometry in adults with osteogenesis imperfecta.

Osteogenesis imperfecta is often regarded as a form of osteoporosis. In many cases, particularly those in whom the first fracture occurs outside the neonatal period, bones that have not been fractured may appear radiologically normal. In a group of 24 adults with osteogenesis imperfecta the thickness of the metacarpal cortex was normal but their bones were often slender. Osteoporosis is probably not an inevitable feature of such cases, and some of the radiological abnormalities reported may be the results of previous fractures and their treatment.

Adult↗
PubMed1975

Computer card morphometry of jejunal biopsies in childhood coeliac disease.

The histological changes in 95 jejunal biopsy specimens from children have been analyzed by a new mporphometric technique. The microscope image of the specimen is traced directly onto computer data cards. A simple sketch records accurate quantitative data in a matrix of 840 points, retaining the spatial arrangement of the tissue components. The data are fed via an optical mark data card reader, into a mini-computer. FORTRAN IV programs allow calculation of surface area, villous heights, and component volumes in metric units, and of volume proportions, volume-to-volume ratios, and surface-to-volume ratios. Pictorial and numerical printouts are produced, which are suitable for inclusion in the patient's notes. Jejunal biopsies from 37 controls and 26 untreated coeliac patients were clearly distinguished morphometrically. Sixteen pairs of biopsies from coeliac patients on long-term gluten-free diets before, and 12 weeks after, the reintroduction of dietary gluten significantly reflected the effects of gluten challenge. Comparison of control and abnormal biopsies showed a spatial redistribution of the components, more than a change in their absolute amounts. There was no significant differences in the total epithelial volumes in controls, treated or untreated patients, suggesting that the mucosal lesion in coeliac disease is not a true atrophy.

Adolescent↗
PubMed1980

Use of morphometry and immunohistochemistry of small intestinal biopsy specimens in the diagnosis of food allergy.

Eight babies with cow's milk protein intolerance and malabsorption, ages ranging from 2 weeks to 6 months, and five adult patients with a history of food allergy were studied. In the jejunal biopsies of the eight children with cow's milk protein intolerance we found partial villous atrophy with an increased number of interepithelial lymphocytes as determined by morphometric analysis. In the five adult patients no morphological changes of the jejunal mucosa were found. However, immunoperoxidase staining revealed a markedly increased number of IgE containing cells in the lamina propria of all jejunal biopsies studied. This proved to be specific for young and adult patients with food allergy. It is concluded that immunohistochemistry of jejunal biopsy specimens is of considerable value in the diagnosis of food allergy.

Adult↗
PubMed1981

Jejunal mucosal morphometry in children with and without gut symptoms and in normal adults.

Nineteen diagnostic peroral biopsy specimens from 18 children without diarrhoea, vomiting, or abdominal pain ('control' children) were compared with those taken from 23 children with diarrhoea of varying aetiology to establish the morphometric characteristics of jejunal mucosa in childhood. Comparison was also made with normal jejunal mucosa from adults. Statistical analysis of each characteristic individually showed no significant difference between the 'control' children and those with diarrhoea, but there were significant differences between the mucosae of 'control' children and those of adults; the villi tended to be shorter and the crypts longer in children. Thirty-seven per cent of specimens from the 'control' children showed a partial villous atrophy, that is, they were abnormal by adult criteria. Discriminant analysis of the features measured showed effective separation of the following groups: normal histology from partial villous atrophy in children, healthy adults from 'control' children, and normal histology in adults from normal histology in children.

Adult↗
PubMed1985

Morphometry of blood monocytes in malignant lymphoma.

Morphometric methods were used to study the ultrastructure of blood monocytes in 23 patients with Hodgkin's disease, 12 patients with non-Hodgkin's lymphoma, and 20 normal subjects. The results were analysed using both univariate and multivariate methods. Both analyses supported the interpretation that the total mitochondrial contribution to the cellular ultrastructure was less in Hodgkin's disease than in the other two groups, with smaller mitochondrial volume fractions, volumes, and surface areas being found. In the patients with non-Hodgkin's lymphoma univariate analysis suggested that monocyte nuclei were larger, with more euchromatin and a relatively smaller heterochromatin-euchromatin interface; the cell profile area was larger and the surface to volume ratio was smaller compared with normal subjects. Morphological changes have not previously been described in blood monocytes in malignant lymphoma, but they may be the counterpart of the known mononuclear phagocyte dysfunction.

Adolescent↗
PubMed1986

Morphometry of spermatozoa using semiautomatic image analysis.

Human sperm heads were detected and tracked using semiautomatic image analysis. Measurements of size and shape on two specimens from each of 26 men showed that the major component of variability both within and between subjects was the number of small elongated sperm heads. Variability of the computed features between subjects was greater than that between samples from the same subject.

Humans↗