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In order to evaluate the evolution (progression and regression) of coronary atherosclerosis, 61 patients (8 with stable angina, 9 with unstable angina, 15 with a recent myocardial infarction, 29 with multivessel coronary artery disease and treated with successful one-vessel angioplasty) were enrolled in a prospective study. In the angioplasty group, only untreated vessels were considered for the analysis. All patients underwent coronary angiography before hospital discharge and after one year, in accordance with the study protocol. In 13 patients (21%) a repeat angiography was performed at 6.3 +/- 2.7 months for clinical reasons (myocardial infarction, changing pattern angina, angina recurrence). All patients were asymptomatic or mildly symptomatic on medical therapy between the angiographic studies. Progression (decrease in internal luminal diameter at the site of stenosis greater than or equal to 20%; new onset of lesions, new episodes of total occlusions) was found in 16 out of 216 stenoses (7%) and in 14 out of 61 patients (23%). Regression (increase greater than or equal to 20% in internal luminal diameter; reopening of a previously occluded vessel) was found in 11 out of 227 lesions (5%) and in 7 out 61 patients (11%). At repeat angiography, the increase in severity was found more frequently in stenoses greater than 5 mm in length and with a reduction of greater than or equal to 75% in luminal diameter. Regression was more frequent in the occluded vessel supplying a recently infarcted area. No significant relationship was observed between lesion morphology (concentric, eccentric, with plaque ulceration, thrombi, border irregularities) and progression or regression. Lesions with plaque ulceration (with or without superimposed thrombi) were found only in patients submitted to coronary angiography close to an acute ischemic attack. Morphologic regression (disappearance of ulceration, border irregularities, thrombi) was also observed, without any significant changes occurring in the severity of the underlying stenosis. Progression may occur independently of worsening in the clinical status; on the contrary, regression was only found in patients without new cardiac events. Nevertheless, clinical status does not seem to be closely correlated to progression, regression, or changes in plaque morphology.
BACKGROUND/AIMS: Little is known about the evolution of morphological changes in pelvic ileal-pouch mucosa. This study evaluates prospectively the sequence of early morphological, histochemical, and phenotypic features in pouch mucosal biopsy specimens. METHODS: Twenty-two patients with pelvic ileal pouches constructed after total colectomy for chronic ulcerative colitis had biopsies performed at the time of ileostomy closure and after 6 weeks and 6 months of pouch function and were evaluated to assess the type and degree of inflammation, villus atrophy, Paneth's cell hyperplasia, mucin histochemical changes, the mucosal proliferative activity using the murine monoclonal antibody 1 (MIB-1), and the expression of the enzyme sucrase-isomaltase. RESULTS: Early changes (6 weeks) were characterized by neutrophilic and eosinophilic inflammation, mild villus atrophy, Paneth's cell hyperplasia, a partial transition to colonic mucin phenotype, and an increased MIB-1 proliferation index. These features remained relatively stable after 6 months, except for a greater degree of mononuclear infiltration, a progressive increase in the degree of eosinophilic inflammation and a new higher steady state level of crypt epithelial kinetics. Expression of sucrase-isomaltase remained stable. CONCLUSIONS: Pelvic ileal pouches develop inflammatory, phenotypic, and kinetic changes early in the course of function but have only a limited potential for colonic type metaplasia. The persistence of these changes is evidence in support of an adaptive response to a new luminal environment.
Serial morphological and cytogenetic investigations were performed in 46 patients with the myelodysplastic syndrome (MDS). Twenty-one patients (45.5%) progressed to AML (greater than 30% blasts in bone marrow smears). Based on sequential determinations of percentages of bone marrow blasts, three patterns of evolution were observed in MDS. Patients with evolution pattern A (48%) had an apparently stable disease with minimal or no increase in bone marrow blasts. Exceptionally they developed new or additional chromosomal anomalies during the course of their disease. Cases in this group, who showed no abnormal localization of immature myeloid precursors (ALIP) at time of diagnosis experienced prolonged survival (median: 43 months), while ALIP positive patients had shorter survival times (median: 14 months), with high probability of early death from infections and/or bleeding problems. Patients with evolution pattern B (28%) initially had a morphologically stable disease, comparable to cases with evolution pattern A, but showed an abrupt shift from MDS to AML. Most of these patients (82%) were ALIP positive and a substantial proportion (46%) showed karyotype anomalies at diagnosis. The abrupt shift to AML in these patients was frequently (61.5%) associated with additional cytogenetic anomalies. Patients with evolution pattern C (24%) showed a gradual increase in bone marrow blasts. The majority of these cases (8/11) ultimately developed acute myeloid leukaemia (gradual progression to AML), whereas some patients (3/11) died from infections and/or haemorrhagic complications before they had reached the level of clinical AML. All of these patients were ALIP positive at diagnosis and no additional cytogenetic alterations occurred during evolution. Acquisition of new karyotypic anomalies during the course of MDS was almost invariably associated with abrupt shift to AML. From this retrospective study we conclude that evolution in MDS shows two important aspects, which seem to be preponderant in determining the course and outcome of the disease: one is the proliferative capacity and resulting growth advantage of the neoplastic clone over normal haematopoiesis, as measured by increasing percentages of bone marrow blasts in sequential aspirates; the other one is instability of the clone. Unstable clones have a high propensity to further intraclonal changes; they are expressed morphologically by the abrupt increase in bone marrow blasts and cytogenetically by the acquisition of new or additional karyotype anomalies.(ABSTRACT TRUNCATED AT 400 WORDS)
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Developmental biology holds keys to our understanding of morphological pattern formation whether these patterns are expressed in the fossil record or among extant species. Though much is known about osseous growth at the cellular level (e.g. Hall, 1991), we have minimal understanding of the coordinated processes that combine to produce a complex, three-dimensional form. We have proposed a framework for the coordinate-free representation of form, a statistical method for comparing and modelling growth trajectories for complex morphologies, and a means for the eventual elucidation of the role of growth in the evolution of morphology. Our method uses the coordinate locations of biological landmarks to represent form as a matrix of all possible linear distances between landmarks, the form matrix. When two forms are expressed in this way, comparison of these forms is accomplished by computing the ratios of like linear distances, the form difference matrix. When the forms being compared are from a growth series, the matrix of ratios is called a growth matrix. Patterns of growth for two groups can be compared by computing the growth difference matrix. We applied growth difference matrix analysis to the study of sexual dimorphism of ontogeny in the M. fascicularis craniofacial skeleton. Growth matrices describing growth in male and female M. fascicularis were presented along with the growth difference matrix that describes sexual dimorphism of growth to underscore the detailed information available from this analytical technique. The method is quite general and can be applied to two- or three-dimensional data sets of landmark coordinates (cross-sectional or longitudinal) collected from almost any developing structure. The methods that we propose enable us to go beyond a mathematical summary of the comparison of forms and the comparison of growth patterns. We provide examples of how growth patterns might be used in the study of phylogenetic relationships. Our plans for use of this method in the study of evolutionary change assumes that morphological change in the craniofacial skeleton results from evolutionary change in developmental units (as defined by Atchley & Hall, 1991) that underlie morphological structure. We believe we have the basic tools to ultimately propose informed phylogenies based solely on developmental data. This task requires the identification of 'growth features' and the polarization of these features as primitive or derived. It is also advisable to determine a set of primitive growth features for the groups of interest. This will necessitate the inclusion of outgroups in our growth analysis.(ABSTRACT TRUNCATED AT 400 WORDS)
Cerebral infarction is the result of cerebrovascular insufficiency and itself creates complex changes in cerebral hemodynamics. To allow recognition of patterns of change in regional cerebral blood flow (r-CBF) caused by cerebral infarction, the authors present an atlas of Tc-99m hexamethylpropyleneamine oxime (Tc-99m HMPAO) SPECT brain scan sections for a variety of strokes demonstrating typical vascular territorial involvements and evolution of morphologic and r-CBF change. Sections from MRI or CT are shown with SPECT images of the stroke lesion for comparison of the complementary information provided by regional cerebroperfusion and by morphology. Examples of SPECT during acute, subacute, and chronic stages of stroke are provided. To illustrate the temporal evolution of stroke and accompanying changes in the "stroke penumbra," case examples of acute tissue necrosis, luxury perfusion, ischemia, and diaschisis are presented. Methods for semiquantitative analysis of morphologic versus r-CBF defect size after acute stroke are described. How brain SPECT scans conducted during Diamox initiated cerebrovascular stress tests can complement the information obtained from baseline studies and assist in the interpretation of r-CBF abnormalities is also demonstrated.
A bibliographic review of a new subject-pemphigus with eosinophilic spongiosis accomplished: Three clinical courses are recognized: a) pemphigus in its initial phase, b) pemphigus markedly seborrheic, which presents during its evolution, some morphologic anomalies, c) pemphigus that appear like an authentic Duhring in its initial phase and during part of its evolution. On studying the histopathology three aspects are observed; 1) pure eosinophilic spongiosis with two modalites: diffuse or vesiculate; 2) mixed eosinophilic spongiosis and, 3) alternate eosinophilic spongiosis. The review report the study of this new observation and discusses the nosological situation as well as its pausible causation.
Five hundred and fifty Wistar rats were investigated to determine the frequency of secondary intestinal perforations after exposure to nonperforating blasts and the evolution of the morphological changes from hematoma through to necrosis and gangrene. The animals were observed at different times for a period of 14 days from the moment that the injury was inflicted. Microscopic findings showed that alterations began in the mucosal layer where they were most extensive, then spread to the submucosal layer, muscular layer, and serosal layer, respectively. Examination of the intestinal wall revealed an evolution of the injury from hematoma to necrosis to gangrene, resulting in secondary intestinal perforation. The secondary wounds had centrifugal patterns, opposite those of the original wound pathways. Based on these observations, the mechanism of evolution of primary nonperforating intestinal blast injury into secondary intestinal perforations is presented.
The authors analyzed the results of a 2-year study of a course of diabetic microangiopathy on the basis of clinical tests and morphological control over microvessels of skin biopsy specimens from 61 patients with diabetes mellitus, of whom 36 regularly received coronary vasodilators (diamicron, pentoxifylline and dipyridamole). The rest of the patients (25) with diabetes mellitus were taken as controls: 10 patients were with unsatisfactory compensation of diabetes mellitus and 15 with a stable metabolic control. A possibility of stabilization and regression of diabetic microangiopathy during prolonged regular administration of coronary vasodilators was shown.
An attempt has been made for identifying different types of granulosa cells in the wall of cavitary ovarian follicles. Human, porcine and rat ovaries have been examined at the light and electron microscopes. Some smears of granulosa cells as well as human foetal ovaries have been also studied. These preliminary results seem to confirm that in the granulosa layer of evolutive follicles the cells may present some different morphological and histochemical features.
A fully automated image analyzing system was developed for the quantitative study of cells in culture. It was able to count cells, to classify cells according to their morphological characteristics and to follow cell culture development. A specific procedure was designed to process Hoffman modulation contrast images. It detects local gray level differences while using conditional dilation techniques. We were able to successfully detect aggregated unstained cells, presently a technical limit in image segmentation. Living cells can be studied in a noninvasive and nondestructive way with this system. An improved automatic focusing algorithm was developed which ensured an accurate prediction of the optimal focus position. A strictly defined sampling procedure was applied to estimate unbiasedly cell density and obtain precisely cell contours. The evaluation of the system was carried out on Chinese hamster ovary (CHO-NTR) cell cultures treated with a newly developed neurotensin agonist JMV449. Chinese hamster ovary cell division was found to be retarded 20 hours after the JMV449 treatment, while the morphology of CHO-NTR cells has already undergone significant changes 12 hours after the treatment. This image analyzing system provides the possibility to follow cell culture development (e.g., cell density evolution, cell morphological changes) under various experimental conditions.
Suramin, a polysulfonated naphtylurea, has been shown to bind to a wide variety of tumor growth factors, and to exhibit anti-proliferative effects on several cell lines. We have followed the suramin-induced (100 micrograms/ml) evolution of morphological, biochemical and electrophysiological changes in HT29-D4 human colonic adenocarcinoma cell clone as a function of culture time. After 5 days of culture in the presence of the drug the cells were polarized and exhibited apical brush border and tight junctions. The polarization process of carcino-embryonic antigen (CEA) in the apical membrane domain was achieved after 8 days of treatment, while the correct localization of HLA class-I molecules in the basolateral membrane domain occurred after 14 days of culture in the presence of suramin. Spontaneous potential difference (PD) and transepithelial resistance (Rt) were recorded from the 9th day of treatment and reached maximum values at day 15 (PD = 3 mV; RT = 450 omega cm2), giving evidence that the differentiation process triggered by suramin concerned virtually all cells in the monolayer. Untreated cells were consistently found to be electrically inactive. Finally, from day 10 of suramin treatment, the lysosomal system was perturbed including accumulation of large autophagic vacuoles and, later, typical lamellar inclusion bodies. These structures were never seen when cells were induced to differentiate in suramin-containing serum-free medium. Moreover, similar perturbations of the lysosomal system could be obtained by adding BSA in the suramin-containing defined medium, suggesting that the lysosomal storage disorder occurring upon suramin treatment was due to endocytosis of suramin-BSA complexes. We conclude that lysosomal impairment due to the presence of BSA in the culture medium did not prevent HT29-D4 cells from differentiating and that it was not an early event which could be involved in the mechanism of action of suramin. However, this perturbation might account for some of the toxic effects occurring during chronic suramin treatment in humans.
Traditionally, living cetaceans (order Cetacea) are classified into two highly distinct suborders: the echolocating toothed whales, Odontoceti, and the filter-feeding baleen whales, Mysticeti. A molecular phylogeny based on 1,352 base pairs of two mitochondrial ribosomal gene segments and the mitochondrial cytochrome b gene for all major groups of cetaceans contradicts this long-accepted taxonomic subdivision. One group of toothed whales, the sperm whales, is more closely related to the morphologically highly divergent baleen whales than to other odontocetes. This finding suggests that the suborder Odontoceti constitutes an unnatural grouping and challenges the conventional scenario of a long, independent evolutionary history of odontocetes and mysticetes. The superfamily Delphinoidea (dolphins, porpoises, and white whales) appears to be monophyletic; the Amazon River dolphin, Inia geoffrensis, is its sister species. This river dolphin is genetically more divergent from the morphologically similar marine dolphins than the sperm whales are from the morphologically dissimilar baleen whales. The phylogenetic relationships among the three families of Delphinoidea remain uncertain, and we suggest that the two cladogenetic events that generated these three clades occurred within a very short period of time. Among the baleen whales, the bowhead is basal, and the gray whale is the sister species to the rorquals (family Balaenopteridae). The phylogenetic position of beaked whales (Ziphioidea) remains weakly supported by molecular data. Based on molecular clock assumptions, the mitochondrial-DNA data suggest a more recent origin of baleen whales (approximately 25 mya) than has been previously assumed (> 40 mya). This revised phylogeny has important implications for the rate and mode of evolution of morphological and physiological innovations in cetaceans.
A morphological study at light and electron microscopy, of 61 cases of intraepithelial epithelioma allowed the authors to distinguish two types of carcinoma: undifferentiated intraepithelial epithelioma arising from the exo-endocervical junction, probably by proliferation of vestigial cells which derived from persistent sinusal remnants; differentiated intraepithelial epithelioma developing upon the mature exocervical epithelium modified by inflammatory processes. These two types of "in situ" epitheliomas have different evolution. The undifferentiated form, supported by an uninterrupted membrane consisting of imbricated reticulin fibres has a slow evolution. The differentiated form, often multifocal, supported by a basal membrane frequently disrupted, has a rapid evolution. These morphological studies allowed the authors to refuse the theory of metaplasia from subcylindrical reserve cells in the genesis of intraepithelial epitheliomas of the cervix.
Since Mivart (1865), Cacajao, Chiropotes, and Pithecia have been grouped into a single taxon, which he called the subfamily Pitheciinae but which I, following Rosenberger (this issue), refer to as the living members of the tribe Pitheciini. While few today doubt the association of these three living genera, not all would place them together with Aotus and Callicebus in the subfamily Pitheciinae. This is an attempt to sort out the behavioral and morphological features of feeding and dental morphology in these taxa. Extant members of the tribe Pitheciini are adapted for sclerocarpic foraging, morphological evidence for which is found in the fossils of Soriacebus and Cebupithecia. Sclerocarpic foraging in living pitheciins is a two-stage process of seed predation involving 1) specialized features of the anterior dentition that allow removal of a hard pericarp that protects a seed or seeds, followed by 2) mastication by the posterior dentition having low cusp relief to triturate nutritious seeds of a relatively soft and uniformly pliable consistency. The dentitions of fossil pitheciins, Soriacebus and Cebupithecia, demonstrate that the hypertrophy of lower incisors plus the robustness and flaring of the canine precede development of low cusp relief on molars and premolars in the evolution of morphological features associated with sclerocarpic foraging. Features of sclerocarpic foraging are found less uniformly in the other two pitheciines, Callicebus and Aotus.
At late stages of anthropogenesis a high positive "hand--foot" structural correlation was disturbed. In paleoanthropuses from the Sxul group and in the fossil man from Sungiry, an excessive development of the fibular components of the foot ("lateralization") was revealed. Certain evolutional and morphological causes contributing to the appearance of this rare variant are considered. A conclusion is made that development of lateralization in the foot can support the hypothesis on transition towards a leading role of the hand at the natural selection of the "hand--foot" system only at the latest stages of anthropogenesis.