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PubMed2000

Phytochemistry and the systematics and ecology of Loasaceae and Gronoviaceae (Loasales).

A screening for iridoid compounds of 78 of 315 species from all major groups in Gronoviaceae and Loasaceae has been carried out. The results were compared to the systematic concepts in the family and distribution and ecology of the taxa. Iridoids are present in at least some species of all genera screened. Some simple, monomeric compounds (e.g., loganin, sweroside) are found in all major groups of the two families and represent the basic iridoid inventory. Other compounds are restricted to certain taxonomic groups: nine-carbon iridoids (e.g., deutzioside) are restricted to Mentzelia (Loasaceae subfam. Mentzelioideae), hetero-oligomeric iridoids (e.g., tricoloroside methyl ester, acerifolioside) are restricted to two small groups in Loasa (Loasa ser. Macrospermae and ser. Floribundae, Loasaceae subfam. Loasoideae), and oleosides (e.g., 10-hydroxyoleoside dimethyl ester) are restricted to the large genus Caiophora sensu Weigend). The distribution of certain iridoid compounds thus confirms some of the generic limits. Iridoid phytochemistry does not correlate with systematic entities above the generic level nor does it in any way correlate with the morphological evolution of taxa. Conversely, the amount and complexity of iridoid compounds present in taxa correlate positively with the aridity of their habitat and the extent of mammalian herbivore pressure.

Journal Article↗
PubMedDate not supplied

[HOX genes in embryo- and phylogenesis].

This review is concerned with the structure and function of the protein products and homeobox genes of the HOX complex. We also trace a relationship between morphological evolution and the evolution of the homeotic complex.

Animals↗
PubMedDate not supplied

[On the problem og higher fungi origin: Florideae hypothesis].

The history and current state of the hypothesis of the origin of higher fungi (Ascomycetes and Basidiomycetes) and red algae from the common ancestor (Florideae) were analysed. Initially the hypothesis was based on similarity of their vegetative and generative structures (Sachs, 1874; Dodge, 1914; Chadefaund, 1953, 1972, etc.), but later it was confirmed by ultrastructural data (Demoulin, 1974; Kohlmeyer, 1975). It appears to be very useful for the study of the development of terrestrial flora (Church, 1921; Kohlemeyer, Kohlmeyer, 1979; Atsatt, 1988) and regularities in morphological evolution of higher fungi (Corner, 1964, 1970; Chadefaud, 1960, 1982, 1984). Description of the order Spathulosporales (Kohlmeyer, 1973), combining the characters of Ascomycetes and parasitic Florideae, was one of the most important fact leading to the wide recognition of the hypothesis in 1970-80s (Cavalier-Smith, 1978; Taylor, 1978; Dodge, 1980; Hawksworth, 1982; Goff, 1983; Coff, Coleman, 1985). Today, however, Florideae hypothesis is not confirmed by molecular data and replaced by alternative hypothesis of Eumycota origin. Summarizing data on molecular systematic of fungi, one could affirm with confidence: 1). Chitincontaining fungi are closer to multicellular animals and green plants than to Rhodophyta; 2). Rhodophyta and Chlorophyta are monophyletic group; 3). There is no single-valued molecular data on taxonomic distance between higher fungi, Chytridiomycetes; Rhodophyta, Chlorophyta and Metazoa. Thus, the current data could not testify against Florideae hypothesis. It is possible to adjust them with the idea of B.M. Kozo-Polyansky (1927) about existence of "Chloroflorodeae" group that is original for terrestrial flora; the hypothesis about closeness of Chlorophyta and Rhodophyta, as well as Chlorophyta and Eumycota, does not contradict molecular data (Stiller, Hall, 1997). The author believes that we need molecular study of the whole "stem" of chlorobionta, especially groups that are close to its basis. It will will help to understand the relationships between Rhodophyta, giant conglomeration of "green algae", chitin-containing fungi, Prasinophyceae and different groups of zoomastigot with maximal resolution--the level of orders or groups of orders. Only such investigation could provide the material for molecular support of phylogenetic constructions. Up to moment Florideae hypothesis is able to exist together with the other ideas.

Ascomycota↗
PubMed2001

[Imaging of the female pelvis in adolescence].

The aim of this chapter is to familiarize the radiologists with the evolutive morphological features of the female genital apparatus, as it can be seen during the puberty, and to view the pathologies panel which may occur in ths period of life. This chapter is going to illustrate the morphological sonographic modifications from the childhood to the adolescence, emphasing the signs of pubertal maturation (uterus and ovaries shape, size and vascularization). Through clinical signs (delayed sexual maturation, primary or secondary amenorrhea, menstrual dysfunction, acute, cyclic, chronic pelvic pain and pelvic mass) the different pathologies are viewed, illustrating the important role of ultrasonography, but not an exclusive role.

Adolescent↗
PubMedDate not supplied

Aetiology of endomyocardial fibrosis (EMF).

On epidemiological basis EMF behaves like a vector transmitted disease. The cardiac pathologies of EMF and HES are identical. In some cases of HES, hypereosinophilia may return to normal, leaving residual heart disease that is exactly like EMF. Most temporary residents from Europe and North America who developed EMF while resident in the endemic areas of Africa had hypereosinophilia that was induced by helminths. In our case studies from the EMF endemic areas of Nigeria, most children with acute idiopathic myocarditis associated with helminth induced hypereosinophilia, developed clinical EMF on follow up. We showed also that the rate of decline in the incidence of hypereosinophilia in EMF cases was significantly related to the duration of symptoms. Our studies and other observations show that EMF, like HES is a multiple system disease with similar organ damage. The morphologic evolution of cardiac damage in EMF appears similar to that reported for HES; with a stage of myocarditis/pericarditis, followed by a stage of cardiac necrosis, a stage of thrombosis and by the chronic fibrotic stage. Also during larval migration, all the helminths associated with EMF induce the same spectrum of damage in the central and peripheral nervous system, in the lungs, kidneys and skin, as are reported for HES. The cardiovascular damage reported for these worms (which include hypersensitivity vasculitis, acute myocarditis/ pericarditis) are also similar to what is reported for HES. Acute endomyocardial necrosis and thrombosis that are similar to what is found in HES, have been documented in Trichinella Spiralis and in filariasis. Increased cerium concentrations have been documented in the endocardium of EMF cases from South India. It remains to be established whether cerium excess, which is known to stimulate collagen synthesis does accelerate the process of endomyocardial fibrosis, following cardiac necrosis (which may have been triggered by helminths and the associated hypereosinophilia).

Animals↗
PubMed1992

[A study on the morphogenesis, tumor marker and DNA content in early gastric signet ring cell carcinoma].

From the study of 20 specimens of micro-signet ring cell carcinoma of stomach, it was noticed that fusiform epithelioid or round monocytoid carcinoma cells were usually found prior to the appearance of signet ring cells. Therefore, from the point of view in morphogenesis, cells of this tumor might be considered better to be differentiated into two stages--early and late stage, which not only represented a morphological evolution of these carcinoma cells, but also expressed their biological characteristics, as it was shown that the expressions of associated antigen to MCab MG-7 and receptors of PNA, PHA reached the highest degree in the monocytoid carcinoma cells, but was markedly attenuated in the signet ring cells and the difference present was 20 times quantitatively additionally, the nuclear DNA content was increased significantly in cancer cells of the early stage, especially the monocytoid cells, with a pattern of aneuploid and polyploid. On the contrary, signet ring cells usually belong to diploid. It seemed logical that monocytoid carcinoma cells would have the greatest value in the early diagnosis of this carcinoma.

Adenocarcinoma, Mucinous↗
PubMed2005

[Gene duplications specific to the amphioxus lineage].

The union of the two complementary disciplines, developmental biology and evolutionary biology resulted in a new division of evolutionary developmental biology, namely "Evo-Devo". Recently, the research on this field has been fruitful in understanding the origin and development of vertebrates. The cephalochordate amphioxus, which remains in relatively invariant morphology since the divergence from the vertebrate lineage, is the closest living relative to vertebrates. The vertebrate-like simple body plan and preduplicative genome provide amphioxus genes the privilege to serve as key landmark to understand morphological evolution. However, the amphioxus genome has not escaped evolution. In this paper several examples of independent gene (Hox; Evx; HNF-3 and Calmodulin-like) duplications in the cephalochordate lineage were summarized. These particularities and oddities remind the fact that amphioxus is not an immediate ancestor of the vertebrates but 'only' the closest living relative to the ancestor, with a mix of prototypical and amphioxus-specific features in its genome.

Animals↗
PubMed2005

Hypertrophic cardiomyopathy with progression from apical hypertrophy to asymmetrical septal hypertrophy: a case report.

A 41-year-old man was referred to our hospital for further examination because of abnormal electrocardiography findings at a health-check examination. Transthoracic echocardiography showed left ventricular hypertrophy confined to the most distal portion of the left ventricle, which is a typical feature of apical hypertrophic cardiomyopathy. Ten years later, he was again admitted for the evaluation of chest pain. Echocardiography showed asymmetrical septal hypertrophy in addition to apical hypertrophy. These findings demonstrate morphologic evolution in hypertrophic cardiomyopathy from apical hypertrophy to asymmetrical septal hypertrophy.

Adult↗
PubMed2005

Origin of the serpentine-endemic herb Layia discoidea from the widespread L. glandulosa (Compositae).

Phylogenetic analyses of nuclear rDNA sequences uphold Gottlieb et al.'s hypothesis that Layia discoidea, a morphologically unusual, serpentine-endemic herb of narrow distribution in central California, "budded off" recently (less than one million years ago) from a nearby lineage of the widespread L. glandulosa, which occurs on sandy soils across much of far western North America. Although L. discoidea and L. glandulosa retain complete interfertility, nuclear rDNA data for the two species are almost free of evolutionary noise, without evidence of gene flow between them; allopatric divergence of L. discoidea cannot be ruled out. Molecular data are consistent with a hypothesis of accelerated morphological evolution of L. discoidea and Gottlieb et al.'s suggestion that the closest relatives of L. discoidea are populations of L. glandulosa with yellow, rather than white, ray corollas, in accord with Clausen, Keck, and Hiesey's evidence of a gene for yellow ray coloration in the rayless L. discoidea.

Asbestos, Serpentine↗
PubMed1990

[Morphologic study of the embryonic development of the Amazonian turtle Podocnemis expansa, Pelomedusidae].

Two egg groups from four clutches of the Amazon turtle, Podocnemis expansa, were incubated at 32-34 degrees C and 35-38 degrees C, respectively. The incubation of the first group lasted approximately 47 days and the second 43 days. To standardize the stages, a series of 25 stages was recorded, based on observation of morphological evolution related to incubation duration and its respective temperatures.

Animals↗
PubMedDate not supplied

Biomechanical interpretations of some bony structures in the skull.

For the causal understanding of some evolutive morphological particularities at the level of the lateral wall of orbits (in mammals and in man), the authors have resorted to biomechanical interpretations of bony structures at the cranium level. To this effect some stress factors as well as the modeling effect on the local bone morphogenesis have been analysed.

Animals↗
PubMed1987

[Comparative anatomy of the velopharyngeal complex in human and non-human primates (2)].

The authors describe the soft palatal-pharyngeal unity, composed of the levator palati and palatopharyngeus muscles in the adult man, the new-born and the Saimiri. They recall the importance of the soft palatal-pharyngeal sphincter in the man's phonation. After having described the general evolution of the aerodigestive tract in the no human mammals and the man, notions of evolutive morphology of the soft palatal-pharyngeal unity are established. They are characterized by the gradual divergence of the axis of the 2 muscles forming the soft palatal-pharyngeal unity ending in the appearance met in the adult man, indispensable in view of a soft palatal-pharyngeal ability allowing a articulated language.

Adult↗
PubMed1987

The development of retina and the optic tectum of petromyzon marinus, L. A light microscopic study.

Morphological evolution of the retina and optic tectum along the stage of ammocoete, transformation and young adult of sea lampreys (Petromyzon marinus L.) was studied using light microscopic techniques and quantitative morphometry. A retinal differentiated zone surrounding the optic nerve head with a kind of differentiated photoreceptors is present through all the stages studied until stage VI of transformation and its extension is almost unchanged since 60 mm. larve. From this length larval retina grows by extension of the lateral undifferentiated retina, that in large larvae subdivides in a lateral germinal zone and an intermediate differentiating zone more thickened were ganglion cells and the optic fibre layer differentiate early. In the largest larvae outer and inner neuroblastic layers were also recognized in these intermediate zone except in the most lateral retina. Mitotic activity was observed both in germinal and intermediate differentiating zones near the optic ventricle. The germinal zone disappears after the formation of an irideal retina in transforming stages and, with the exception of the photoreceptor layer, retinal layers were differentiated since stage III along the neural retina. The photoreceptor layer develops in the early stage VI along the retina. Adult pattern of retinal pigmentation is found in these stage. A periventricular and a lateral region were recognizable in the optic tectum of the larval period. Tectum of large larvae shows an outline of laminar organization. In the stage III of transformation the tectal lamination is the same of the young adults: the periventricular cell layer is subdivided by fibre bands and in the lateral region a stratum cellulare centralis and a stratum cellulare et fibrosum externum were distinguishable. A comparison between retinal and tectal growths was made. Most retinal and tectal growth and differentiation occurs before adult photoreceptors develop.

Aging↗
PubMed1974

Schwann cell properties. II. The identity of phagocytes in the degenerating nerve.

The present study was undertaken to identify the cells from which phagocytes originate following traumatic injury to the sciatic nerves in rats. The morphologic evolution of the phagocytes was correlated daily with changes in axon, myelin, Schwann cell and neurilemmal tube at light and electron microscopic levels. Autoradiography with tritiated thymidine was employed to label the proliferative cells immediately before and following the injury. The result indicated that degeneration of Schwann cells occurred with the onset of myelin breakdown and that the degenerated products of myelin, axon and Schwann cells were removed by macrophages. While most of the macrophages were originally blood monocytes, some were derived from vascular pericytes. They penetrated the neurilemmal tubes on the third postoperative day and began engulfing first the Schwann cells and then the myelin and axons. Having filled their cytoplasm with debris, some macrophages moved out of the neurilemmal tube while others remained temporarily inside the envelopes formed by the persisting neurilemmal tubes-thus the macrophages can inherit a basal lamina from degenerated Schwann cells.

Animals↗
PubMed1979

Morphologic observations on experimental corneal vascularization in the rat.

The morphologic evolution of the early events of corneal vascularization in the rat cornea induced by silver nitrate cautery were followed by light and electron microscopy. An initial acute inflammatory response occurred within the first 6 hours after cautery as evidenced by vascular dilation, diapedesis of leukocytes, and an increased vascular permeability, as manifested by distended lymphatics and the presence of extravascular fibrin. At 24 hours after injury, the hypertrophy and the prominence of nucleoli and the presence of abundant polyribosomes were the initial suggestion that vascular endothelial cells and pericytes had entered the mitotic cycle. Nine hours later, at 33 hours after cautery, the first new vessels were observed as sprouts from the capillary arcade and postcapillary venules. The experiments reemphasize the association of acute inflammation and corneal vascularization in this model and underscore the early occurrence of vascular endothelial cell replication.

Animals↗
PubMed1995

[The first experience in Russia of using DNA diagnosis in Alport's syndrome in a family with a unique morphological picture of the kidney lesion].

Clinicomorphological findings are reported for two children from families with hereditary predisposition to hematuria characterized by early occurrence of chronic renal insufficiency, neurosensory hypoacusis, congenital ocular abnormalities inherited by sex-linked dominant type. Light microscopy of nephrobiopsies revealed diffuse mesangial proliferation in both children. Final diagnosis of Alport's syndrome was feasible only on molecular-genetic level after polymerase chain reactions had identified mutation in collagen type 4 alpha-5-chain gene on a long arm of X-chromosome in genotypes of both patients and their mothers. Genetical, clinical, morphological, evolutional and diagnostic aspects of Alport's syndrome are reviewed.

Adolescent↗
PubMed1993

Variable morphology of human immunodeficiency virus-associated lymphomas with c-myc rearrangements. The French Study Group of Pathology for Human Immunodeficiency Virus-Associated Tumors, I.

Burkitt lymphoma (BL) and immunoblastic lymphoma (IL) are the most frequent lymphoid tumors encountered in human immunodeficiency virus (HIV)-infected patients. Tumors with a morphology intermediate between BL and IL, and the existence of Burkitt's type translocations in some IL cases makes the classification of these tumors sometimes unclear. We have studied 14 cases of BL and IL in HIV-seropositive individuals with regard to clonality, Epstein-Barr virus (EBV) association, and the presence of c-myc rearrangement. Of seven tumors with morphology of BL, all were monoclonal, six showed a c-myc rearrangement and four were associated with EBV. Five tumors with morphology of IL were associated with EBV and devoid of c-myc rearrangement. Three were polyclonal representing EBV-driven lymphoproliferations similar to those observed in transplant recipients. Two tumors, one with a morphology of IL and the other intermediate between IL and BL were monoclonal, associated with EBV, and harbored a c-myc rearrangement. We propose that these last two tumors represent cases of BL that have adopted an immunoblastic morphotype in the context of acquired immunodeficiency syndrome (AIDS), reflecting the morphologic evolution of Burkitt lymphoma cells observed in culture.

Adult↗