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PubMed1984

Large cell lymphomas. I. Differential diagnosis of centroblastic and B-immunoblastic subtypes by morphometry on histologic preparations.

Thirty-three large cell lymphomas, 18 centroblastic or large noncleaved follicle center cell lymphomas and 15 B-immunoblastic lymphomas, diagnosed by morphology and marker studies, were studied with morphometry. The following parameters were studied: nuclear and nucleolar area, nuclear shape, cytoplasm-to-nucleus ratio, number of nucleoli per nuclear cross section, location of the nucleolus within the nucleus as expressed by the relative nucleolar eccentricity (rNE), and the percentage of morphometrically defined immunoblasts. Mean values and standard deviations (SDs) were calculated and statistically analyzed. The two groups differed significantly in their nucleolar area (mean and SD), cytoplasm-to-nucleus ratio (mean), number of nucleoli per nuclear cross section (mean and SD), rNE (mean), and percentage of immunoblasts. Using nonlinear discriminant analysis, the possibility of classifying individual cases with the studied parameters was investigated. Twenty-nine cases were reliably classified (88%); three were classified correctly, but with less than a 95% certainty, and 1 case was misclassified. The results indicate a spectrum ranging from centroblastic to B-immunoblastic lymphoma. Transition forms occur and can be accurately defined with morphometry.

Adult↗
PubMed2000

Disruption of spatial organization and interjoint coordination in Parkinson's disease, progressive supranuclear palsy, and multiple system atrophy.

Patients with basal ganglia diseases may exhibit ideomotor apraxia. To define the nature of the impairment of the action production system, we studied a repetitive gesture of slicing bread by three-dimensional computergraphic analysis in eight nondemented patients with Parkinson's disease in the "on" state, five with progressive supranuclear palsy and four with multiple system atrophy. Two patients with Parkinson's disease and two with progressive supranuclear palsy showed ideomotor apraxia for transitive movements on standard testing. A Selspott II system was used for kinematic analysis of wrist trajectories and angular motions of the shoulder and elbow joints. Patients with Parkinson's disease, progressive supranuclear palsy, and even some with multiple system atrophy exhibited kinematic deficits in the spatial precision of movement and velocity-curvature relationships; in addition, they failed to maintain proper angle/angle relationships and to apportion their relative joint amplitudes normally. Spatial disruption of wrist trajectories was more severe in patients with ideomotor apraxia. We posit that the basal ganglia are part of the parallel parieto-frontal circuits devoted to sensorimotor integration for object-oriented behavior. The severity and characteristics of spatial abnormalities of a transitive movement would therefore depend on the location and distribution of the pathologic process within these circuits.

Aged↗
PubMed1983

Kinematics of cranial vault growth in rabbits.

To characterize mathematically the spatial rearrangement of cranial vault bones of the rabbit during growth, a longitudinal study was undertaken from age 4-20 weeks. Initially, at least three nonlinear tantalum bone markers were implanted in the parietal, frontal, and the combined nasal bones. Thereafter, the animals were followed regularly with roentgen stereophotogrammetrical analysis. The parietal bones were found to rotate laterally upward (3 degrees), while the frontal bones rotated downward (2 degrees) relative to their contralaterals. The frontal bones rotated rostrally upward (12 degrees) and outward (3 degrees) as well as laterally downward (5 degrees) in relation to the parietal bones. Due to the morphology of the rabbit head, the examination positioning used in this study, and the direction of the growth process, growth at the coronal suture correlated fairly well with longitudinal axis translations; but the growth at the frontonasal suture relative to the frontal bones was directed about 45 degrees downward. This points to the importance of the bone-marker positioning, so that their connecting line is directed along the axis of growth. Also, this approach makes it possible to obtain new information on the development and treatment of craniofacial aberrations.

Animals↗
PubMed1986

The correlation between craniofacial and long bone growth: an experimental investigation in normal rabbits.

The present study was undertaken to elucidate the relationships between craniofacial and long-bone growth. Nine male New Zealand white rabbits received spherical tantalum bone markers in the tibial epiphyses and in the nasal, frontal, and parietal bones. The animals were followed from 30 to 143 days of age. Growth changes were calculated with a roentgen stereometric system, and the results statistically evaluated. Except for the final interval when all variables varied at random, high correlations between tibial and frontonasal or coronal sutural growth were demonstrated; and the respective linear regression lines were homogeneously assembled. The relationship between the tibia and the sagittal suture displayed great variations between individual animals as well as between the suture's parts, although growth at the interfrontal suture was clearly correlated to tibial growth upon exclusion of the time factor. The first principal component of the three neurocranial sutures was calculated and seemed accurately correlated to long-bone growth. The present study concluded that growth at the frontonasal and coronal sutures normally seems to parallel general somatic development, while growth at the sagittal suture appears individually displaced in time. Nevertheless, when the principal component of the combination of the coronal suture and the neurocranial section of the sagittal suture was computed, this was highly correlated to body growth.

Age Factors↗
PubMed1990

Variability of measurements of cranial growth in the rabbit.

This study concerns techniques used in experimental cranial growth research: roentgen cephalometry, roentgen stereophotogrammetry, and gross measurements (osteometry). A comparison of the precision of these methods has not been found in the literature. Computation of technical errors is fundamental to the sound evaluation of registered findings, and such a presentation must be obligatory in all biometric reports. We compared the measurement error of roentgen cephalometric and osteometric data with that obtained by roentgen stereophotogrammetry (RSA). RSA demonstrates a superior replicability, and this technique gives possibilities for kinematic and volumetric determinations simultaneously with distance evaluation. Roentgen cephalometry has the advantage of enabling distance and angular measurements between any well-defined skeletal points or lines. This technique, preferably after implantation of bone markers, is a reliable alternative, but optimal results necessitates calculations of the magnification factor for each bone segment involved. Direct osteometry does not contribute additional information, but problems of image magnification are omitted. Preferably, one individual should perform all measurements regardless of the method used. Growth rates and values calculated by one technique cannot be directly transformed to some other approach. In all probability, assessments of distance changes would gain substantially by using one technical approach consistently throughout actual age intervals. The least variable measurements of sutural growth are made for sutures growing primarily in one plane and with substantial growth rates. One must realize that differences among studies may be due to the limitations of, in particular, the cephalometric and osteometric techniques.

Animals↗
PubMed1991

Photogrammetric evaluation in clinical genetics: theoretical considerations and experimental results.

As newer mathematical approaches are applied to the field of clinical genetics accurate methods of craniofacial measurement are increasingly necessary. If photogrammetric techniques are to be used certain theoretical and practical issues must be taken into account. Errors due to projection are particularly important, but systematic and random errors must also be considered. We discuss theoretical aspects of projection errors along with experimental measurements. Systematic errors in excess of 20% were found during simulations of typical clinical conditions, although smaller errors were obtained using techniques practical in a clinical setting. Photogrammetric measurements are potentially valuable in the field of clinical genetics but must be used cautiously.

Cephalometry↗
PubMed1985

Fringe patterns and measurement on dorsal moiré topography in Japanese children, aged 13 and 14.

Dorsal moiré topographies of 165 boys and 156 girls, aged 13 and 14, were investigated. Moiré fringe patterns were classified into seven types, of which type IV, thin and symmetric back, was most frequent (29% in boys and 22% in girls), and types I and II thoracic, fleshy back, were observed in 15% of boys and 29% of girls. Settling four prominent points on the back, length, depth (number of fringes), angles between these points, and the most depressed point on the lumbar region were measured. Neither bilateral or sex differences were detected in length and depth measurements, whereas larger right side angles were observed as a general tendency. In both sexes, significant correlation was detected between measurements on points situated in the inner part of the back, while on points situated in the outer parts only angle and length correlation was significant.

Adolescent↗
PubMed1979

Morphology of the atrioventricular node, bundle and proximal bundle branches: a study employing computerized reconstruction.

The morphology of the human atrioventricular node, atrioventricular bundle and bundle branches is described. A block of tissue bounded by the ostium of the coronary sinus, the pars membranacea, the septal leaflet of the tricuspid valve and the atrial and ventricular septa is removed. The block is then sectioned serially from the right endocardial surface in the frontal plane of the heart. Sectioning in this way produces fewer sections than from techniques previously described. Outlines of the atrioventricular node, atrioventricular bundle and proximal bundle branches are digitally registered and stored in a computer. Three dimensional reconstructions of the structures are then generated by computer and displayed on an oscilloscope so that the entire three dimensional image can be rotated in any plane. Stereoscopic image pairs are produced to assist perception of the shape of the atrioventricular node, bundle and branching patterns of the bundles. This technique is unique in that it describes a method from which a relatively small number of histologic sections are generated permitting not only a complete histologic examination, but also a study of the morphology of the area.

Adult↗
PubMed1985

Volumetric changes in the developing rabbit calvarium.

Tantalum bone markers were implanted in the frontal, parietal, and temporal bones, at least two in each bone segment, in seven male New Zealand white rabbits. Roentgen stereophotogrammetric analyses were performed for regular intervals between ages 30 to 142 days. With the exception of a few implants in the temporal bone, bone markers remained stable during the observation period. Volumetric and longitudinal growth data were compared. Calvarial polyhedron volumes increased linearly. Growth at the actual neurocranial sutures demonstrated an individually fluctuating pace. No obvious correlation between volumetric and longitudinal growth was noted. This might be explained by sagittal and temporal suture growth in periods being close to the methodological error and failure to document bone rotations. Previous observations on the linearity in cerebral weight increase during corresponding periods of time points to the decisive role of neural mass growth in calvarial development in rabbits. Suture growth characteristics are discussed.

Animals↗
PubMed1992

Formation of secretory granules in the Golgi apparatus of prolactin cells in the rat pituitary gland: a stereoscopic study.

The mode of secretory granule formation in prolactin cells was analyzed in thin or thick sections of pituitary glands from non-lactating or lactating female as well as from male rats. In all these animals, the Golgi apparatus of prolacting cells consists of a continuous twisted ribbon-like structure that branches and anastomoses to form a hollow sphere located in the juxtanuclear area. The early signs of secretory granule formation are observed along the trans-aspect of the Golgi ribbon where progranules appear as focal distensions simultaneously occurring anywhere in the last trans thiamine pyrophosphatase (TPPase)-containing Golgi element. In the transmost Golgi saccule, such dilatations usually contain several nodular masses of electron opaque material which are separated from each other and from the saccular membrane by a less intensely stained material. While this transmost saccule becomes more fenestrated, its focal polynodular distensions seemingly yield polynodular tubular progranules which are initially closely apposed and usually parallel to the trans face of the Golgi ribbon. Subsequently, these progranules, which frequently show small membranous tubules or tubular networks attached to them, are seen some distance from the Golgi stacks and progressively transform into the more compact polymorphous granules characteristic of prolactin cells. These observations suggest that the polynodular tubular progranules arise by fragmentation of portions of the trans-Golgi elements rather than by fusion of small uninodular granules budding from the edges of a trans-Golgi saccule. Once the progranules have been liberated, the rest of the transmost Golgi element appears to break down into small residual networks, tubules, and vesicles. Thus, in prolactin cells as in other glandular cells, the whole transmost Golgi element would fragment during formation of prosecretory granules.

Animals↗
PubMed1993

Stereological study of mouse uterine and in vitro grown blastocysts: cell numbers and volumes.

Mouse blastocysts were studied to determine if there were differences in cell number and volumes between those that were 1) derived from the uterus prior to implantation on the afternoon of day 4 of pregnancy and 2) those that were cultured for 72 hr from two-cell-stage embryos. Blastocysts were fixed, embedded in resin, and serially sectioned at 1.5 or 2 microns. Photographic prints of alternate sections were used to count the numbers of inner cell mass (ICM) and trophectoderm cells. Cavalieri's direct estimator was applied to the same prints to estimate the volume of the whole blastocyst. Point counting was used to determine the volumes of the ICM, trophectoderm, and zona pellucida. The number of cells and size of the ICM were similar between the two groups of blastocysts, although it was found that the ICM of uterine embryos that did not have a zona pellucida were smaller than the ICM of those that did. There were twice as many trophectoderm cells in the blastocysts that were cultured from two-cell embryos, and these cells were also found to be larger. Furthermore, the volume of the zona pellucida was less in the uterine blastocysts. This study indicates that, while trophectoderm proliferation is enhanced in vitro, the ICM is more constant and thus may be self-regulating and independent of the growth conditions of the blastocysts as a whole. This study also suggests partial zona lysis occurs in utero and occurs either at a reduced rate or not at all in vitro.

Animals↗
PubMed1994

Stereological and serial section analysis of chondrocytic enlargement in the proximal tibial growth plate of the rat.

BACKGROUND: It has been suggested that within the growth plate, the final volume and shape of hypertrophic chondrocytes are important variables in determining the rate of longitudinal bone growth. To better understand the organization and regulation of chondrocytic hypertrophy as related to longitudinal bone growth, the beginning and end, and the location and magnitude of chondrocytic volume and shape changes during the hypertrophic process were defined in the proximal tibial growth plate of 35-day-old rats. METHODS: In this study we used two different approaches, a stereological analysis of chondrocytes in unbiasedly defined, narrow growth plate strata, and a serial section reconstruction and measurement of individual cells. In both experiments chondrocytes were preserved using optimal chemical fixation. Proliferating chondrocytes were identified using bromodeoxyuridine labelling, and the rate of longitudinal bone growth was determined using oxytetracycline labelling. RESULTS: In both studies, immediately following cell division in the proliferative zone, chondrocytic volume gradually increased toward the mid-point of the growth plate. During this phase of about 30 hours, approximately 20% of the final cell volume was obtained. During the following 20 hours the remaining 80% was acquired. The estimated rate of cell volume increased changed from approximately 50 microns 3/hr during the first 30 hours to about 800 microns 3/hr during the last 20 hours. The increase in cell volume resulted in an increase in both the vertical and the horizontal chondrocytic diameters. Cell parameters did not change during the final five hours of the maturation process. CONCLUSIONS: In this study we demonstrated that chondrocytic enlargement starts immediately following cell division in the proliferative zone, and that chondrocytic enlargement consists of two morphologically distinguishable phases. The transition point between the first and the second phase of chondrocytic enlargement corresponded with the junction between the proliferative zone and the maturation zone.

Animals↗
PubMed1995

Estimation of capillary length density in skeletal muscle by unbiased stereological methods: I. Use of vertical slices of known thickness.

BACKGROUND: The unbiased estimation of the capillary length density in skeletal muscle tissue Lv(cap/mus) has been performed in this study applying a new stereological methodology based on the use of vertical slices and the intersections of cycloid test curves with capillaries in a three-dimensional space defined by systematically chosen fields of vision and the thickness of the sections. METHODS: The following simple requirements must be fulfilled: selection of a fixed vertical axis in skeletal muscle, adequate systematic muscle sampling, obtention of vertical slices of constant and known thickness but indifferent in magnitude, superposition of a cycloid test system with the minor axis of cycloid curves positioned perpendicularly to the vertical axis, and counting the intersections between cycloid curves and capillaries. In our study, the vertical axis was defined as that which is parallel to the natural, major axis of the muscle where fibres and capillaries are arranged parallel to this axis. The muscle sampling was performed using the fractionator method, and 25 microns thick sections were chosen. RESULTS: The application of the equation for estimation of Lv(cap/mus) permits determination of an average of 1,480 mm of capillaries per mm3 of muscle tissue, knowing the number of intersections, section thickness, and the points hitting the muscle with a known ratio between cycloid test curve length to a test point. CONCLUSIONS: The estimation of Lv(cap/mus) is efficient, unbiasedly obtained, and no assumptions on the degree of capillary anisotropy are required.

Animals↗
PubMed1995

Estimation of capillary length density in skeletal muscle by unbiased stereological methods: II. Use of vertical slices of unknown thickness.

BACKGROUND: The capillary network of the skeletal muscle was analyzed from a quantitative point of view with the purpose of determining the capillary length density--LV(cap/mus). A recent stereological method was applied to estimate this quantity using vertical slices of unknown thickness. METHODS: First, the whole muscle was systematically sampled according to the fractionator method. The capillary length density was estimated on each chosen field of vision where the vertical axis was always identified as parallel to the major axis of the muscle fibers. Three measurements were performed: count of intersections between capillaries and cycloid test lines, count of intersections between capillaries and straight test lines, and count of capillary end points corresponding to the intersections of capillaries with the parallel planes of the vertical slices. RESULTS: The estimated capillary length density was 1,578 mm per mm3 of skeletal muscle tissue. The average thickness of the vertical slices was also estimated as 23.4 microns, which is roughly 6% less than the thickness measured using the microcator information on the microscope stage displacement. CONCLUSIONS: The advantages of this methodology were based on two main features: the method is assumption-free on the degree of capillary and muscle anisotropy, and the thickness of the vertical slices need not be known nor constant.

Animals↗
PubMed1984

Direct visualization of particle velocity distribution by pseudostereoscopic viewing of time-lapsed sequential images: application to fast axonal transport.

We describe a simple method for direct visualization of the velocity distribution of particles moving against an immobile background. The technique involves pseudostereoscopic viewing of image pairs separated by an appropriate time interval in a sequential recording of the subject. Under these conditions, the positive or negative parallax arising from particle motion results in the binocular image of a particle being perceived as raised or lowered relative to an immobile background plane depending on its direction of movement, and with the degree of perceived elevation being proportional to its speed. In effect, the binocular optic axis becomes a velocity (speed) axis under these conditions. The technique is illustrated with examples of image pair sequences showing fast axonal transport in lobster and squid axons using video-enhanced differential interference contrast microscopy. However, the pseudostereoscopic method is quite generally applicable to both microscopic and macroscopic time-dependent phenomena. Particle speeds can be quantitated using standard procedures for measuring frame-to-frame particle displacements, or alternatively, by determination of parallax using stereogrammatic methods. It should be also readily adaptable for on-line monitoring of particle velocity distribution, particularly in video systems where frame buffers can be utilized to extract and present serial image pairs having any desired time separation from video-taped sequences.

Animals↗