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PubMed1989

Can tegumental morphology be used as a taxonomic criterion between Schistosoma haematobium, S. intercalatum, and S. bovis?

A comparative study of the evolution in time of the tegumental morphology of male adult Schistosoma haematobium from Niger, S. intercalatum from Cameroon and Zaire, and S. bovis from Spain and Sudan was carried out with scanning electron microscopy. Interindividual, interstrain, and interspecies variations are pointed out. The value of the morphological criterion (tegument with or without spines) is discussed. The tegumental morphology can be used for the identification of schistosome species showing strong phyletic affinities under precise experimental conditions. In the present work, this criterion permits the characterization of strains of S. bovis from Sudan and Spain.

Animals↗
PubMed1984

Rapid radiometric methods to detect and differentiate Mycobacterium tuberculosis/M. bovis from other mycobacterial species.

Rapid methods for the differentiation of Mycobacterium tuberculosis/M. bovis (TB complex) from other mycobacteria (MOTT bacilli) were developed and evaluated in a three-phase study. In the first phase, techniques for identification of Mycobacterium species were developed by using radiometric technology and BACTEC Middlebrook 7H12 liquid medium. Based on 14CO2 evolution, characteristic growth patterns were established for 13 commonly encountered mycobacterial species. Mycobacteria belonging to the TB complex were differentiated from other mycobacteria by cellular morphology and rate of 14CO2 evolution. For further differentiation, radiometric tests for niacin production and inhibition by Q-nitro-alpha-acetyl amino-beta-hydroxy-propiophenone (NAP) were developed. In the second phase, 100 coded specimens on Lowenstein-Jensen medium were identified as members of the TB complex, MOTT bacilli, bacteria other than mycobacteria, or "no viable organisms" within 3 to 12 (average 6.4) days of receipt from the Centers for Disease Control. Isolation and identification of mycobacteria from 20 simulated sputum specimens were carried out in phase III. Out of 20 sputum specimens, 16 contained culturable mycobacteria, and all of the positives were detected by the BACTEC method in an average of 7.3 days. The positive mycobacterial cultures were isolated and identified as TB complex or MOTT bacilli in an average of 12.8 days. The radiometric NAP test was found to be highly sensitive and specific for a rapid identification of TB complex, whereas the radiometric niacin test was found to have some inherent problems. Radiometric BACTEC and conventional methodologies were in complete agreement in Phase II as well as in Phase III.

Cells, Cultured↗
PubMed2004

The histological aspects of fillers complications.

The histological aspects of resorbable heterologous fillers (bovine collagen, acid hyaluronique), autologous fillers (lipofilling, dermis-fat graft), biodegradable fillers (New-Fill), and permanent fillers (silicone, Artecoll, Evolution, Aquamid, DermaLive, DermaDeep, Bioplastique, Paraffin) are described. This article relates the morphological aspect of these materials, the normal tissue reaction after injection, and its chronological evolution as the morphological aspects from the different side effects, more frequently observed for the permanent fillers. They mainly consist of granulomatous reactions which may appear long after injection.

Animals↗
PubMed2003

Convergence and coevolution in a mutualism: evidence from a molecular phylogeny of Ficus.

The interaction between Ficus (Moraceae) and their pollinating wasps (Chalcidoidea: Agaonidae; more than 700 species-specific couples) is one of the most specialized mutualisms found in nature. Both partners of this interaction show extensive variation in their respective biology. Here we investigate Ficus life-history trait evolution and fig/fig wasp coadaptation in the context of a well-resolved molecular phylogeny. Mapping out variations in Ficus life-history traits on an independently derived phylogeny constructed from ribosomal DNA sequences (external and internal transcribed spacer) reveals several parallel transitions in Ficus growth habit and breeding system. Convergent trait evolution might explain the discrepancies between morphological analyses and our molecular reconstruction of the genus. Morphological characters probably correlate with growth habit and breeding system and could therefore be subject to convergent evolution. Furthermore, we reconstruct the evolution of Ficus inflorescence characters that are considered adaptations to the pollinators. Our phylogeny reveals convergences in ostiole shape, stigma morphology, and stamen:ovule ratio. Statistical tests taking into account the phylogenetic relationship of the species show that transitions in ostiole shape are correlated with variation in wasp pollinator head shape, and evolutionary changes in stigma morphology and stamen:ovule ratio correlate with changes in the pollination behavior of the associated wasp. These correlations provide evidence for reciprocal adaptations of morphological characters between these mutualistic partners that have interacted over a long evolutionary time. In light of previous ecological studies on mutualism, we discuss the adaptive significance of these correlations and what they can tell us about the coevolutionary process occurring between figs and their pollinators.

Adaptation, Biological↗
PubMed1996

Climbing, brachiation, and terrestrial quadrupedalism: historical precursors of hominid bipedalism.

The vertical-climbing account of the evolution of locomotor behavior and morphology in hominid ancestry is reexamined in light of recent behavioral, anatomical, and paleontological findings and a more firmly established phylogeny for the living apes. The behavioral record shows that African apes, when arboreal, are good vertical climbers, and that locomotion during traveling best separates the living apes into brachiators (gibbons), scrambling/ climbing/brachiators (orangutans), and terrestrial quadrupeds (gorillas and chimpanzees). The paleontological record documents frequent climbing as an ancestral catarrhine ability, while a reassessment of the morphology of the torso and forelimb in living apes and Atelini suggests that their shared unique morphological pattern is best explained by brachiation and forelimb suspensory positional behavior. Further, evidence from the hand and foot points to a terrestrial quadrupedal phase in hominoid evolution prior to the adoption of bipedalism. The evolution of positional behavior from early hominoids to hominids appears to have begun with an arboreal quadrupedal-climbing phase and proceeded though an orthograde, brachiating, forelimb-suspensory phase, which was in turn followed by arboreal and terrestrial quadrupedal phases prior to the advent of hominid bipedality. The thesis that protohominids climbed down from the trees to become terrestrial bipeds needs to be reexamined in light of a potentially long history of terrestriality in the ancestral protohominid.

Animals↗
PubMed2006

Low-copy nuclear DNA, phylogeny and the evolution of dichogamy in the betel nut palms and their relatives (Arecinae; Arecaceae).

For the betel nut palm genus Areca and the other seven genera in subtribe Arecinae (Areceae; Arecoideae; Arecaceae) we collected DNA sequences from two low-copy nuclear genes, phosphoribulokinase (PRK) and the second largest subunit of RNA polymerase II (RPB2). The data were used to evaluate monophyly of the subtribe and its component genera, explore the radiation of the group across its range, and examine evolution of protandry and protogyny, which is particularly diverse in Arecinae. The subtribe and some genera are not monophyletic. Three lineages of Arecinae are recovered: one widespread, but centered on the Sunda Shelf, another endemic to the islands east of Wallace's line and a third, comprising the Sri Lanka endemic Loxococcus, that is most closely related to genera from outside subtribe Arecinae. Strong support is obtained for broadening the circumscription of the genus Hydriastele to include Gronophyllum, Gulubia and Siphokentia. In clarifying phylogenetic relationships, we have demonstrated that a perceived bimodal distribution of the subtribe across Wallace's line does not in fact exist. Character optimizations indicate that the evolution of protogyny, an unusual condition in palms, is potentially correlated with a large radiation in the genus Pinanga and possibly also to dramatic diversification in pollen morphology and genome size. The evolution of dichogamy in the clade endemic to the east of Wallace's line is complex and reveals a pattern of numerous transformations between protandry and protogyny that is in marked contrast with other Arecinae. We suggest that this contrast is most likely a reflection of differing geological histories and pollinator spectra in each region.

Arecaceae↗
PubMed2006

Evo-devo and constraints on selection.

Developmental bias, or genetic channeling, can influence the tempo and direction of evolution and, thus, become reflected in patterns of biodiversity. Twenty years ago, this notion rested on armchair descriptions of potential constraints on evolution. Now, a broad evo-devo approach involving both evolutionary and developmental genetics provides experimental analysis of such bias, revealing how shared genetic or developmental pathways among morphological traits contribute to the evolution of complexity and diversity, and that developmental bias itself evolves, generating variation in evolvability. As I discuss here, it is now possible to determine the relative importance of natural selection and of genetical and developmental architecture as determinants of organic diversity, particularly for examples of adaptive radiations and parallel evolution.

Animals↗
PubMed2004

Keeping sensory cells and evolving neurons to connect them to the brain: molecular conservation and novelties in vertebrate ear development.

The evolution of the mechanosensory cellular module and the molecular details that regulate its development has included morphological modifications of these cells as well as the formation of larger assemblies of mechanosensory cell aggregates among metazoans. This has resulted in a wide diversity of mechanosensory organs. The wide morphological diversity of organs, including the associated morphological modifications of the mechanosensory cells, suggests parallel evolution of these modules and their associated organs. This morphological diversity is in stark contrast to the molecular conservation of developmental modules across phyla. These molecular data suggest that the evolution of mechanosensory transduction might have preceded that of distinct cellular differentiation. However, once a molecular network governing development of specialized cells involved in mechanosensory transduction evolved, that molecular network was preserved across phyla. Present data suggest that at least the common ancestor of triploblastic organisms, perhaps even the common diploblastic ancestor of bilaterian metazoans, had molecular and cellular specializations for mechanosensation. It is argued that the evolution of multicellular organs dedicated to specific aspects of mechanosensation, such as gravity and sound perception, are evolutionary transformations that build on this conserved molecular network for cellular specialization, but reflect distinct morphological solutions. We propose that the sensory neurons, connecting the craniate ear with the brain, are a derived feature of craniates, and possibly chordates, that came about through diversification of the lineage forming mechanosensory cells during development. This evolutionarily late event suggests a heterochronic shift, so that sensory neurons develop in mammals prior to mechanosensory hair cells. However, sensory neuron development is connected to hair cell development, likely in a clonal relationship. The theme of cellular conservation is reiterated in two examples of chordate otic diversification: the evolution of the horizontal canal system and the evolution of the basilar papilla/cochlea. It is suggested that here again, cellular multiplication and formation of a special epithelium predates the functional transformation to an 'organ' system for horizontal angular acceleration and sound pressure reception, respectively. Overall, evolution of the vertebrate ear needs to be understood as an interplay between and utilization of two gene networks or modules. One is at the level of the molecularly and developmentally conserved mechanosensory cellular module. The other is an increased complexity in the morphology of both adult mechanosensory cells and organs by the addition of end-stage and novel features and associated gene networks to detect specific aspects of mechanosensory stimuli.

Animals↗
PubMed1993

Histologic assessment of the age of recent brain infarcts in man.

In order to design a dating system based on the microscopic picture of brain infarcts of recent onset, we performed the histological examination of 31 infarcts covering the first 4 weeks of evolution in 30 autopsy cases. The date of the cerebral vascular accident was clinically established in every case. There were 13 men and 17 women with a mean age of 65 years. Hemorrhagic infarcts were found in 15 cases and anemic infarcts in 16 cases. Based on the histological features four periods were identified: the first period, from day 1 through day 4, was characterized by the predominance of eosinophilic neurons and necrotic oligodendrocytes; the second period, from day 5 through day 7, differed from the first by the appearance of macrophages and of newly formed blood vessels; the third period, from day 8 through day 14, showed neuronal ghosts, macrophages, astrocytic proliferation, gemistocytes, and absence of neutrophils; and in the fourth period, from day 15 through day 27, there were no eosinophilic neurons, and neither necrotic oligodendrocytes nor myelin in the central portion of the infarct were identified. By assessing the histological features and accurately correlating the findings with the corresponding clinical data, we have been able to describe four distinct microscopic patterns of the first month of evolution of brain infarcts. The present findings may be considered useful morphological clues to better characterize the early evolutional phase of brain infarcts in humans.

Aged↗
PubMed1985

Primary structure of glucagon from an elasmobranchian fish. Torpedo marmorata.

Glucagon has been isolated from the pancreas of Torpedo marmorata, an elasmobranchian cartilaginous fish, and purified to homogeneity using only reverse-phase high-performance liquid chromatography. Amino acid sequence analysis indicates that the molecule differs from mammalian glucagon at position 3 (glutamic acid for glutamine), position 16 (asparagine for serine), and position 20 (lysine for glutamine). Extracts of T. marmorata intestine and brain were associated with glucagon-like immunoreactivity determined by radioimmunoassay using antisera directed against the C-terminal and N-terminal to central regions of porcine glucagon. Although elasmobranchian and teleostean fish are believed to have diverged from the main line of vertebrate evolution at about the same time, the structure of two glucagons from the teleost, Lophius americanus (anglerfish) differ from mammalian glucagon by seven and nine residues. This study supports the assertion that the structure of glucagon has been highly conserved during evolution and suggests that the considerable morphological development of the pancreas is teleosts was associated with an accelerated rate of molecular evolution.

Amino Acid Sequence↗
PubMed1977

Joint remodelling and the evolution of the human hand.

A funtional morphological study has been made of the joints of the primate hand, particular emphasis being placed upon the carpometacarpal and metacarpophalangeal joints. The presumptive evolutionary history of these joints has been charted by reference to a comparative series of mammals. It has been demonstrated that the human joints have been quite strikingly modified in a number of ways, and that these evolutionary changes may be logically correlated with the refined functional attributes of the human hand. The morphological background thus established has been applied in a preliminary study of the hand bones of various fossil hominids.

Animals↗
PubMed2003

Cytogenetic and morphologic typing of 58 papillary renal cell carcinomas: evidence for a cytogenetic evolution of type 2 from type 1 tumors.

We evaluated clinical characteristics, patient outcome (mean follow-up, 47 months), and cytogenetic abnormalities in the largest as yet reported cytogenetic series of 47 primary and 11 secondary papillary renal cell carcinomas for differences between the recently proposed type 1 and type 2 subtypes. Secondary tumors were more often of type 2 morphology (P = 0.02), whereas primary type 2 tumors were associated with higher clinical stage (P = 0.001) and worse patient outcome (P = 0.02). Although both subtypes had at least one of the primary chromosomal gains at 17q, 7, and 16q, type 2 tumors had moderately lower frequencies of primary gains at 17p (61 versus 94%; P = 0.007) and 17q (72 versus 97%; P = 0.02). On the other hand, type 2 tumors overall had more chromosomal alterations than type 1 tumors (P = 0.01), particularly gains of 1q (28 versus 3%; P = 0.02) and losses of 8p (33 versus 0%; P = 0.001), 11 (28 versus 3%; P = 0.02), and 18 (44 versus 9%; P = 0.01). Hierarchical clustering suggested cytogenetic patterns common but not restricted to type 2 morphology, one characterized by multiple additional gains, and another predominantly showing additional losses. These findings provide genetic evidence that type 1 and type 2 tumors arise from common cytogenetic pathways and that type 2 tumors evolve from type 1 tumors. Independently of type, losses of 9p were statistically correlated with advanced disease (P = 0.0008) and may serve as a potential adverse prognostic marker in papillary renal cell carcinomas.

Adult↗
PubMed1983

[Current concepts of the biology of the development of the human head. Observations and hypotheses].

Morphological dynamics controlling vertebrate embryo development, which takes place in flotation in a liquid medium, leads to the hypothesis that the pentameric symmetry of echinodermes, ancestors of the vertebrates, is conserved during evolution. This embryogenesis consists of morphological repetitions: synchronous growth of five expansions specialized in exploration and spatial deplacements (head and four limbs); each of these five expansions consists of five buds or five radii (facial buds, fingers and toes). Homomorphism of the mouth, of the hands, and of the feet--which are capture catastrophes over the environment, installed early during development--allows later functional and sensory connections. These morphological repetitions are also demonstrated by the association of facial, hand, and foot buds, malformations for which a topological correspondance can be shown. During vertebrate morphogenesis by flotation in a liquid medium, other phenomena take place. For instance, the palate is formed anteriorly by a triple junction resulting from the fusion of its three constitutive buds.

Congenital Abnormalities↗
PubMed1982

[New concepts of the biology of human cephalic development. Observations and hypotheses].

Morphological dynamics controlling vertebrate embryo development, which takes place in flotation in a liquid medium, leads to the hypothesis that the pentameric symmetry of echinodermes, ancestors of the vertebrates, is conserved during evolution. This embryogenesis consists of morphological repetitions: synchronous growth of five expansions specialized in exploration and spatial deplacements (head and four limbs); each of these five expansions consists of five buds or five radii (facial buds, fingers and toes). Homomorphism of the mouth, of the hands, and of the feet--which are capture catastrophes over the environment, installed early during development--allows later functional and sensory connections. These morphological repetitions are also demonstrated by the association of facial, hand, and foot buds, malformations for which a topological correspondence can be shown. During vertebrate morphogenesis by flotation in a liquid medium, other phenomena take place. For instance, the palate is formed anteriorly by a triple junction resulting from the fusion of its three constitutive buds.

Animals↗
PubMed1994

[Several comments and various considerations on Von Brunn nests].

Subsequent to a certain amount of aggression, the vesical epithelium can induce some histological changes which would range from the most innocent morphological vicarious forms to the most aggressive neoplastic types (transitional, squamous and/or glandular tumours). Co-existence in the same urothelium of metaplastic, dysplastic and/or neoplastic lesions should not therefore be a surprise. With the intention of assessing the urothelium evolutive potential, we present a morphological study of the male cervix-trigonal epithelium abnormally involved in the steroidal hormones immunosuppression and actions. The typical patches of "female cervical trigonitis" have not been seen in this epithelium although there has been a wide range of evolutive possibilities of squamous and/or glandular lineage. Both tissular options have a clear metaplastic etiology. They present neither atypia not dysplasia, but participate of the distinctive dynamics of Von Brunn nidi. (C. Pellicé Jr: Doctorate Thesis, 1990). Of all the various evolutive options displayed by the urothelium when subjected to aggression, this study will focus on the Von Brunn nidi because of their atypical behaviour, their peculiar histogenesis and their dubious and controversial participation in vesical carcinogenesis.

Epithelium↗
PubMed2006

Molecular phylogeny and biogeography of Picea (Pinaceae): implications for phylogeographical studies using cytoplasmic haplotypes.

The center of diversity is not necessarily the place of origin, as has been established by many plant molecular phylogenies. Picea is a complicated but very important genus in coniferous forests of the Northern Hemisphere, with a high species diversity in Asia. Its phylogeny and biogeography were investigated here using sequence analysis of the paternally inherited chloroplast trnC-trnD and trnT-trnF regions and the maternally inherited mitochondrial nad5 intron 1. We found that the North American P. breweriana and P. sitchensis were basal to the other spruces that were further divided into three clades in the cpDNA phylogeny, and that the New World species harbored four of five mitotypes detected, including two ancestral ones and three endemics. These results, combined with biogeographic analyses using DIVA and MacClade and fossil evidence, suggest that Picea originated in North America, and that its present distribution could stem from two times of dispersal from North America to Asia by the Beringian land bridge, and then from Asia to Europe. Most of the northeastern Asian species and the European P. abies could arise from a recent radiation given the very low interspecific genetic differentiation and pure mitotype of them. Considering that the ancestral mtDNA polymorphism can be preserved in many descendant species, even distantly related ones, we suggest that more species, at least the closely related ones, should be sampled in the phylogeographical study using cytoplasmic haplotypes if possible. In addition, we also discussed the evolution and phylogenetic utility of morphological characters in Picea.

Base Sequence↗
PubMed2001

Interrelationships and evolution of the tapeworms (Platyhelminthes: Cestoda).

Interrelationships of the tapeworms (Platyhelminthes: Cestoda) were examined by use of small (SSU) and large (LSU) subunit ribosomal DNA sequences and morphological characters. Fifty new complete SSU sequences were added to 21 sequences previously determined, and 71 new LSU (D1-D3) sequences were determined for the complementary set of taxa representing each of the major lineages of cestodes as currently understood. New sequences were determined for three amphilinidean taxa, but were removed from both alignments due to their excessively high degree of divergence from other cestode sequences. A morphological character matrix coded for supraspecific taxa was constructed by the modification of matrices from recently published studies. Maximum-parsimony (MP) analyses were performed on the LSU, SSU, LSU+SSU, and morphological data partitions, and minimum-evolution (ME) analyses utilizing a general time reversible model of nucleotide substitution including estimates of among-site rate heterogeneity were performed on the molecular data partitions. Resulting topologies were rooted at the node separating the Gyrocotylidea from the Eucestoda. The LSU data were found to be more informative than the SSU data and were more consistent with inferences from morphology, although nodal support was generally weak for most basal nodes. One class of transitions was found to be saturated for comparisons between the most distantly related taxa (gyrocotylideans vs cyclophyllideans and tetrabothriideans). Differences in the topologies resulting from MP and ME analyses were not statistically significant. Nonstrobilate orders formed the basal lineages of trees resulting from analysis of LSU data and morphology. Difossate orders were basal to tetrafossate orders, the latter of which formed a strongly supported clade. A clade including the orders Cyclophyllidea, Nippotaeniidea, and Tetrabothriidea was supported by all data partitions and methods of analysis. Paraphyly of the orders Pseudophyllidea, Tetraphyllidea, and Trypanorhyncha was consistent among the molecular data partitions. Inferences are made regarding a monozoic (nonsegmented) origin of the Eucestoda as represented by the Caryophyllidea and for the evolution of the strobilate and acetabulate/tetrafossate conditions having evolved in a stepwise pattern.

Animals↗