Alveolization: does "A" stand for appropriate morphometry?
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Animals↗
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Results for “morphometry”
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Betamethasone and the rhesus fetus: effect on lung morphometry and connective tissue.
Pregnant rhesus monkeys (Macaca mulatta) at 67 to 85% of term pregnancy were treated with betamethasone for 3 days and then delivered by cesarean section. These treated fetuses had larger lung volumes (32.6 +/- 1.8 ml/kg of body weight) compared to gestational age-matched controls (22.9 +/- 3.2 ml/kg of body weight; P less than 0.025) but no alterations in surfactant properties as measured by amniotic fluid L/S ratios, alveolar deflation stability, or lung phosphatidylcholine. These findings suggest that betamethasone effects an increase in fetal lung volume by some method other than alteration in alveolar surfactant concentrations. Results also demonstrated an 11% increase in the collagen to elastin concentration in the treated fetuses as compared to the control animals (P less than 0.01), suggesting alterations in lung connective tissue. Morphometric studies done on the air-fixed inflated lung demonstrated a decrease in the number of alveoli per unit volume of lung among the treated animals (0.95 +/- 0.07 x 10(6)) compared to the control animals (1.19 +/- 0.08 x 10(6); P less than 0.025) and a reduction in the mean surface area of the lungs of the treated animals (506 +/- 10 cm2 per cm3) compared to the control animals (561 +/- 9 cm2 per cm3; P less than 0.005). These findings suggest that at least part of the increased maximal lung volumes is related to increased alveolar distensibility. Together, these pressure volume findings, biochemical studies, and morphometric analyses indicate that a major effect of betamethasone on the rhesus fetal lung is to alter lung connective tissue characteristics. Alterations in lung surfactant appear to be of less functional significance in this rhesus fetal model. The disparity between these findings and other animal studies might be due to differences in species, the preparation, or the method of glucocorticoid administration.
Animals↗
Morphometry of hypoplastic fetal guinea pig lungs following amniotic fluid leak.
Deficient quantity of amniotic fluid causes fetal guinea pig lung hypoplasia. Oligohydramnios that lasts only 5 days in early gestation is sufficient to reduce fetal lung growth significantly. We quantitated lung structural alterations at 50 days gestation (term is 67 days) of fetal guinea pigs whose amniotic fluid was drained on day 45 gestation. The study period spans the late canalicular-early saccular phases of guinea pig lung growth. Compared to littermate controls (n = 4), experimental fetuses (n = 5) have reduced lung:body weight ratio (2.81 +/- 0.16 versus 3.21 +/- 0.20 X 10(-2), p less than 0.01), indicating lung hypoplasia. Lung volume is significantly decreased in the experimental fetuses (1.17 +/- 0.15 versus 1.34 +/- 0.07 ml, p less than 0.05). The proportion of lung containing parenchyma (i.e. developing alveoli and alveolar ducts) is reduced following oligohydramnios (0.83 +/- 0.04 versus 0.90 +/- 0.02, p less than 0.025). The hypoplastic lungs contain fewer saccules (fetal "alveoli") (46 +/- 20 versus 69 +/- 23 X 10(6), p less than 0.1) and the surface area that would be available for gas exchange is decreased (698 +/- 234 versus 974 +/- 80 cm2, p less than 0.05). Lung volume and volume proportion of parenchyma are reduced in the experimental lung and therefore diminished parenchymal elastic tissue is anticipated. However, the total length of parenchymal elastic tissue in the experimental lungs is decreased to a surprising degree and is little more than half the length in control lungs (504 +/- 222 versus 974 +/- 70 m, p less than 0.0025). Such marked reduction in total length suggests that factors other than smaller lung size have contributed to the decrease of elastic tissue in the experimental group. In fact, elastic tissue length per unit volume is significantly reduced (509 +/- 189 versus 809 +/- 115 m/cm3, p less than 0.025) indicating an absolute decrease in parenchymal elastic tissue in the hypoplastic lungs.(ABSTRACT TRUNCATED AT 250 WORDS)
Amniotic Fluid↗
Antenatal endotoxin and glucocorticoid effects on lung morphometry in preterm lambs.
In utero inflammation may accelerate fetal lung maturation but may also play a role in the pathogenesis of chronic lung disease. We examined the impact of endotoxin, a potent proinflammatory stimulus, on structural and functional maturation of preterm sheep lungs. Date bred ewes received 20 mg Escherichia coli endotoxin or saline by ultrasound guided intra-amniotic injection at 119 d gestation. A comparison group of animals received 0.5 mg/kg betamethasone, a known maturational agent, at 118 d gestation. Lambs were delivered by cesarean section at 125 d (term = 150 d) and ventilated for 40 min. Lung function data are reported elsewhere. Total and differential white cell counts were performed on amniotic fluid and fetal lung fluid samples. Morphometric analyses were performed on inflation fixed right upper lobes. Total cell count increased slightly but not significantly in both amniotic fluid and fetal lung fluid. Both endotoxin and betamethasone had similar effects on alveolarization: average alveolar volume increased by approximately 20% and total alveolar number decreased by almost 30%. Both treatments led to thinning of alveolar walls, although this was statistically significant in the betamethasone-treated group only. Although antenatal endotoxin leads to striking improvements in postnatal lung function, this may be at the expense of normal alveolar development.
Amniotic Fluid↗
The association between bone mineral density, metacarpal morphometry, and upper limb fractures in children: a population-based case-control study.
The aim of this population-based case-control study was to examine the association between bone mass and upper limb fractures in children aged 9-16 yr. Areal bone mineral density and bone mineral apparent density (BMAD) were measured by both dual energy absorptiometry (DXA) and metacarpal index (MI) by hand radiograph. A total of 321 fracture cases and 321 randomly selected individually matched controls were studied. For all fractures, cases had lower DXA measures at all sites (1.1-3.3%; all P < 0.05). A larger reduction was observed for those with wrist and forearm fractures (1.2-4.5%; all P < 0.05, except total body BMAD) but not other upper limb fractures (hand, -1.6 to +1.2%; upper arm: 0.9-4.8%; all P > 0.05). For metacarpal measures, cases had a thinner cortical width and lower MI for wrist and forearm fractures only. In multivariate modeling, both spine BMAD (odds ratio, 1.4/SD reduction) and MI (odds ratio, 1.5/SD reduction) remained statistically significant predictors of wrist and forearm fractures. In conclusion, both DXA measures and MI are independently associated with wrist and forearm but not other upper limb fractures. The magnitude of this association is somewhat weaker than in adults but suggests that optimizing age-appropriate bone mass will lessen the risk of fracture in children.
Absorptiometry, Photon↗
Morphometry and histology of gonads from twelve children and adolescents with the androgen insensitivity (testicular feminization) syndrome.
Gonadal histology was investigated by means of stereology and Conventional microscopy in 12 patients, aged 2 months to 19 yr, with the androgen insensitivity syndrome (AIS). Eight patients had the incomplete variant of the syndrome and 4 patients had the complete form. Testicular tissue was removed as a prophylactic measure in all patients. In 6 patients less than 5 yr of age testicular histology was normal, except for slightly decreased mean tubular diameters, and, in 1 of the patients, abnormal morphology of the germ cells including a carcinoma-in-situ pattern. The number of germ cells was within the normal range in these 6 patients. In contrast, in older patients (greater than 7 yr of age), germ cells were absent or present only in small foci. In patients with the complete AIS the testicular histology also was immature after puberty, whereas some maturation and subsequent degeneration was found in adolescent patients with the incomplete form of the syndrome. In addition, 2 of these latter patients had a carcinoma-in-situ germ cell pattern. Although patients with the AIS have no reduction of the number of germ cells during the first years of life, this syndrome is associated with abnormal morphology of the germ cells, including patterns of carcinoma-in-situ and impaired pubertal maturation of the seminiferous tubules and the germ cells, in older patients.
Adult↗
Frequency of nerve fiber degeneration of peripheral motor and sensory neurons in amyotrophic lateral sclerosis. Morphometry of deep and superficial peroneal nerves.
Among 10 patients with amyotrophic lateral sclerosis who had combined biopsy of muscle and cutaneous nerves, two had a history of paresthesia that suggested involvement of peripheral afferent neurons. Of four patients without paresthesia, two had unequivocal abnormalities of touch-pressure sensation of the toe. On morphometric evaluations of lateral fascicles of deep peroneal nerve, one nerve had an abnormally low myelinated fiber density and seven of 10 had abnormally high frequencies of teased-fiber abnormalities. Teased fibers in which myelin was degenerating into linear rows of myelin ovoids and balls occurred in 10.5 percent of fibers in amyotrophic lateral sclerosis nerves as compared with 1.7 percent in control nerves (0.01 less than p less than 0.025). Estimates of density of myelinated fibers were less sensitive than estimates of the frequency of various changes in teased fibers for detecting abnormality.
Aged↗
Quantitative CT analysis of brain morphometry in adult Down's syndrome at different ages.
Quantitative CT demonstrated that healthy adults with Down's syndrome (DS) have smaller brains and smaller intracranial volumes than controls. Normalized volumes of CSF, ventricles, and brain parenchyma did not differ in patients and controls. Both DS subjects and controls showed similar significant age-related increments in volumes of CSF and ventricles. Of seven older DS subjects, one was demented, whereas the group as a whole showed reductions in cognitive test scores as compared with younger DS subjects. The results demonstrate cognitive decline in older DS subjects, but no brain atrophy other than that expected with aging.
Adult↗
Selective neuroanatomic abnormalities in Down's syndrome and their cognitive correlates: evidence from MRI morphometry.
We examined the pattern of neuroanatomic abnormalities in adults with Down's syndrome (DS) and the cognitive correlates of these abnormalities. Specifically, we compared this pattern with what would be predicted by the hypotheses attributing DS pathology to either premature aging or Alzheimer's disease. We measured a number of brain regions on MRIs of 25 subjects: 13 persons with the DS phenotype and 12 age- and sex-matched healthy volunteers. Study participants had no history of cardiovascular disease, diabetes, thyroid dysfunction, or seizure disorder. After statistical adjustment for differences in body size, we found that, in comparison with controls, DS subjects had substantially smaller cerebral and cerebellar hemispheres, ventral pons, mammillary bodies, and hippocampal formations. In the cerebellar vermis of DS subjects, we observed smaller lobules VI to VIII without appreciable differences in other regions. In addition, we noted trends for shrinkage of the dorsolateral prefrontal cortex, anterior cingulate gyrus, inferior temporal and parietal cortices, parietal white matter, and pericalcarine cortex in DS subjects compared with normal controls. The parahippocampal gyrus was larger in DS subjects. We found no significant group differences in the volumes of the prefrontal white matter, the orbitofrontal cortex, the pre- and postcentral gyri, or the basal ganglia. We conclude that the pattern of selective cerebral damage in DS does not clearly fit the predictions of the premature aging or Alzheimer's disease hypotheses. To examine the relationship between brain abnormalities and cognitive deficits observed in DS, we correlated the size of brain regions that were significantly reduced in DS with performance on tests of intelligence and language. The correlation analysis suggested age-related decline in the DS subjects in general intelligence and basic linguistic skills. General intelligence and mastery of linguistic concepts correlated negatively with the volume of the parahippocampal gyrus. There was no relationship between total brain size and the cognitive variables.
Adult↗
Brain morphometry in Tourette's syndrome: the influence of comorbid attention-deficit/hyperactivity disorder.
Three separate groups, using MRI, have reported basal ganglia abnormalities in Tourette's syndrome (TS). We found similar abnormalities in boys with attention-deficit/hyperactivity disorder (ADHD). Because TS and ADHD are frequently comorbid, we contrasted ADHD boys with and without TS along with control subjects. As expected, we found a significant loss of the normal globus pallidus asymmetry in the patients, but presence or absence of TS did not differentiate the ADHD groups. We conclude that accounting for ADHD comorbidity will be important in future TS morphometric studies.
Adolescent↗
Midline cerebral morphometry distinguishes frontotemporal dementia and Alzheimer's disease.
We investigated and contrasted midline cerebral structures in frontotemporal dementia (FTD) and Alzheimer's disease (AD). FTD and AD may be difficult to distinguish clinically. FTD typically affects frontal and anterior temporal regions, whereas AD tends to involve more posterior temporal and parietal areas. We hypothesized that disease-specific cerebral alterations would be differentially reflected in corresponding regions of the corpus callosum (CC), pericallosal CSF space (PCS), or their ratio (CC:PCS). Regions-of-interest (ROIs) from midsagittal MRIs in 17 AD, 16 FTD, and 12 elderly control (EC) subjects were analyzed. ROIs were divided into four regions using an anatomic landmark-based computer algorithm and were adjusted for head size variation. FTD subjects had a much smaller anterior CC region and significantly larger PCS area, particularly in anterior regions. AD and EC subjects did not differ significantly in any total or regional ROI measure. Total and anterior CC:PCS ratios were markedly lower in FTD patients. Across groups, total CC:PCS correlated significantly with midsagittal cerebral area and was similarly associated with Mini-Mental State Examination score. Anterior CC (AD) and PCS (FTD) regions exhibited disease-specific relationships to these variables. A discriminant model using two ROI variables correctly classified 91% of AD and FTD patients, comparing favorably with blind clinical MRI diagnostic ratings. Midline cerebral structural alterations reflect differential patterns of cerebral degeneration in AD and FTD, yielding morphometric indices that may facilitate the study of brain-behavior relationships and differential diagnosis of dementia.
Aged↗
Hat size, brain size, intelligence, and dementia: what morphometry can tell us about brain function and disease.
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Aged↗
Cell versus nuclear morphometry of serum-stimulated fibroblasts: nuclear changes precede cell changes.
Changes in the cell and nuclear morphology of sparsely plated WI38 fibroblasts were followed as a function of time after increasing the serum concentration from 0.3% to 10%. Quantitative measurements were carried out in parallel on Feulgen-stained nuclei and Wright-stained cells using the Quantimet 720-D image analysis system. We report a rapid, significant change in nuclear morphology indicative of nuclear rounding taking place within 30 min after increasing the serum concentration. In contrast, cell morphology showed only a slight change within the first 30 min but showed a significant change, also indicative of cell rounding, between 30 min and 3 h after increasing the concentration. Thus our results indicate a coupling between cell and nuclear morphology, but one in which nuclear changes precede cellular changes. As variations in both cell and nuclear morphology have been linked to the control of cell growth and transformation we also discuss briefly the implications of our results in relation to the regulation of cell growth and transformation.
Blood↗
Regional and developmental variations of blood vessel morphometry in the chick embryo chorioallantoic membrane.
Avian eggs contain all the necessary materials for embryonic development except for oxygen, which diffuses in from the environment via pores in the hard, calcified eggshell to the chorioallantoic membrane (CAM), the respiratory organ, which is rich in blood vessels. An air cell is formed at the blunt pole of the egg between the two membranes of the eggshell and enlarges during incubation due to water vapor loss. In this study of the CAM of chicken eggs, we compared blood vessel numerical density [N(A(v))], area fraction of blood vessels [A(A(v))], CAM thickness (D(CAM)), total length of blood vessels (L) and surface area of the CAM attached to the eggshell (CAMre) with those under the air cell (CAMac) during incubation. We found that N(A(v)), A(A(v)), D(CAM) and L of the CAM increase with embryonic age and development. The N(A(v)), A(A(v)) and L under the air cell were higher in relation to the rest of the CAM at all ages tested, while the D(CAM) under the air cell was always lower than around the rest of the egg. Since the eggshell over the air cell has a relatively greater porosity, and the respiratory gas exchange ratio there is higher than at other areas of the egg, there is a correlation between all the above morphometric data and the eggshell porosity. This suggests optimization of embryonic gas exchange in the chicken egg. We would like to propose that, during natural incubation, an increased gas diffusion under the air cell, together with increased blood vessel numerical density, may compensate for covering of the central part of the eggshell by the incubating parent.
Age Factors↗
The respiratory development of Atlantic salmon. I. Morphometry of gills, yolk sac and body surface
During development from larva to juvenile in Atlantic salmon, Salmo salar, there is a change in the anatomical potential for gas exchange among gills, body skin and yolk sac as the larvae resorb yolk, grow and develop gills. Newly hatched Atlantic salmon have poorly developed gills but do have a high skin area to mass ratio and a large well-vascularized yolk sac. Cutaneous surfaces accounted for over 95 % of the total area available for respiration in newly hatched Atlantic salmon (body mass 0.032­0.060 g). The branchial contribution to total area increased rapidly, however, so that by the end of yolk absorption (body mass 0.19­0.23 g) it constituted 22 % of the total area and overtook cutaneous surface area between 5 and 6 g wet body mass. Harmonic mean diffusion distance across the skin increased through development from 20 µm at hatch (14 µm across the yolk sac) to 70 µm in an 11 g fish. Diffusion distances across both the filaments and lamellae of the gills decreased through development, from 3.7 to 2.4 µm for lamellae and from 14.5 to 10.8 µm for filaments. The total anatomical diffusion factor (ADF, mass-specific surface area per unit diffusion distance) remained constant over early development and appeared to be higher than in adult fish. The distribution of ADF changed over early development from 50 % yolk sac, 42 % body surface and 8 % branchial in newly hatched fish to 68 % branchial and 32 % cutaneous at the end of yolk resorption. Generally, early post-hatch development of gills, ADF and some cutaneous surfaces showed high mass exponents. After yolk resorption (body mass 0.2 g), however, these coefficients were lower and closer to unity. The change in scaling at the end of yolk resorption in this study may reflect the completion of larva to juvenile metamorphosis in Atlantic salmon. Comparison between our data and values in the literature suggests that the timing of gill development is related more to developmental stage than to body size.
Journal Article↗
Three-dimensional morphometry of spinal cord injury following polyethylene glycol treatment.
We are developing a novel means of restoring function after severe acute spinal cord injury. This involves a brief application of polyethylene glycol (PEG) to the site of injury. In the companion paper, we have shown that a delayed application of PEG can produce strikingly significant physiological and behavioral recovery in 90-100 % of spinal-cord-injured guinea pigs. In the present paper, we used three-dimensional computer reconstructions of PEG-treated and sham-treated spinal cords to determine whether the pathological character of a 1-month-old injury is ameliorated by application of PEG. Using a novel isocontouring algorithm, we show that immediate PEG treatment and treatment delayed by up to 7 h post-injury statistically increased the volume of intact spinal parenchyma and reduced the amount of cystic cavitation. Furthermore, in PEG-treated animals, the lesion was more focal and less diffuse throughout the damaged segment of the spinal cord, so that control cords showed a significantly extended lesion surface area. This three-dimensional computer evaluation showed that the functional recovery produced by topical application of a hydrophilic polymer is accompanied by a reduction in spinal cord damage.
Administration, Topical↗
Three-dimensional morphometry in ultrasound.
The clinical use of three-dimensional (3D) ultrasound has rapidly spread to many specialities over the last ten years. The reason is easy to see, namely that single two-dimensional (2D) scans are often difficult to interpret and the mental correlation of multiple 2D scans to form a 3D image of anatomical morphology is taxing and uncertain. The rapid development of techniques for the realtime tracking of the spatial position and orientation of ultrasound probes and the development of computer graphics techniques for the presentation of anatomical images have made 3D ultrasound a realistic diagnostic tool. The authors describe the range of methods of data acquisition and display and provide illustrations of some current clinical applications.
Adult↗
Measurement imprecision in vertebral morphometry of spinal radiographs obtained in the European Prospective Osteoporosis Study: consequences for the identification of prevalent and incident deformities.
Several algorithms are currently in use for evaluating vertebral deformities from plain lateral radiographs of the lumbar and thoracic spine. However, the effects of measurement imprecision as well as uncertainties over image magnification on the correct identification of prevalent and incident vertebral deformities with these algorithms has been little studied. In a pilot study for the European Prospective Osteoporosis Study (EPOS), plain radiographs were submitted to a single central evaluating centre for measurement of vertebral height from T4 to L4. The thoracic and lumbar spines were imaged on separate films, and we have assessed the precision of measurement of vertebral heights and height ratios. The standard deviation of the differences between films of each of three height measurements ranged from 1.1 to 1.2 mm. A two-stage strategy for identifying incident deformities was devised. This required that the vertebra be a prevalent deformity at the time of the second radiograph and also that at least one of the vertebral ratios should have changed significantly since the first radiograph. The second stage removed all but two of the 18 vertebrae flagged positive in the first stage but not considered to be certain incident fractures by clinical reading of the radiographs.
Aged↗