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PubMed1979

[Echocardiographic diagnosis of obstructive myocardiopathies: study of the systolic anterior motion of the mitral valve and septal hypertrophy as compared with the hemodynamic and mechanographic findings. Evolution under medical treatment].

Characteristic echocardiographic features of hypertrophic obstructive cardiomyopathy were recorded in 24 patients, all of whom had asymmetric septal hypertrophy and systolic anterior motion of the mitral valve (SAM) at rest or after pharmacodynamic stimulation. The relationship between outflow tract obstruction and SAM was assessed by comparison with data obtained at cardiac catheterisation and external mechanography: SAM seems to be a non-specific phenomenon and may be recorded in cases of hypertrophic cardiomyopathy without obstruction during pharmacodynamic stimulation. In forms with obstruction, SAM and the severity of obstruction increase with the degree of spetal hypertrophy. The increased contractility of the left ventricular posterior wall appears to be an important factor in the mechanism of SAM which can be prevented by betablockade in moderate or labile forms. When SAM is permanent, whatever the gradient recorded, it is a sign of anatomical deformation of the left ventricle and may be an additional indication for cardiac surgery.

Adrenergic beta-Antagonists↗
PubMed1993

How are more complex brains different? One view and an agenda for comparative neurobiology.

Do more complex brains operate on the same principles as simpler brains, merely employing more of the same; or has evolution produced new principles? A neglected research agenda is the search for relevant differences between brains of animals belonging to different major grades of complexity and cognitive capacity. More complex brains are believed to be capable of more transactions, discriminations, memory and repertoire--functional criteria of 'better' brains. While comparative cognition needs to test these expectations to verify what would be one of the major consequences of evolution, comparative neurobiology needs to discover what, in detail, by all the methods and measures of neuroanatomy, neurophysiology and neurochemistry, is different in more complex brains and which of these differences are relevant to behavioral differences. Formerly it was fashionable to deny differences in the dimension that might be called higher and lower. The criterion of complexity, defined as the number of different parts, processes, interactions and behaviors, may be a useful index of advancement. Unequivocal advancement has occurred between some major taxa, although it is not inevitable. Anatomically, it is clear that novelties have evolved and complexity is more than size or number of the same components. Physiologically, new types of cells, local and larger circuits and emergent properties of assemblies have increased the complexity of operations and organization. It needs to be reasserted that more complex brains have evolved repeatedly, both among invertebrates and among vertebrates, because similar assertions have been incorrectly labeled as 'intuitive scaling' and anthropocentric or moral statements.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1998

Evolution of disc degeneration in lumbar spine: a comparative histological study between herniated and postmortem retrieved disc specimens.

This is a prospective comparative histological study on blood supply between lumbar herniated discs and postmortem retrieved ones. The aim of this study is to observe the evolution of disc degeneration in relation to its blood supply changes. Disc vascularization is present early in life, but the nucleus pulposus becomes avascular after adolescence. Vascularization of the annulus fibrosus (AF) probably also occurs late in life in association with degenerative changes and in response to trauma. Capillary neoformation and hypervascularity in degenerated discs have also been mentioned, based on animal cases. In the present study, intervertebral lumbar disc specimens were surgically removed from 84 patients with an average age of 41 years (range 24-60 years) operated on for disc herniation. In addition, control autopsy specimens were selected from 24 cadavera with an age of 39 years (range 24th gestation week to 80 years). The material was fixed in neutral buffered formalin, and 4-microm-thick sections were stained with hematoxylin-eosin and reticulin. In addition, with use of an immunohistochemical avidin-biotin complex technique, paraffin sections were stained for Ulex europaeus agglutinin receptors (UEA-1) after binding UEA-1 to the tissue. In surgical specimens, small blood vessels were identified in 45% of the disc cases. They were of the capillary-type vessels and were intermingled with proliferating endothelial cells, fibroblasts, and few mononuclear cells. All of them were located along the edges of the surgically retrieved fibrocartilage fragments. Sometimes thin bands of fibrin were attached to them and extravasated erythrocytes were occasionally seen. In autopsy specimens, blood vessels were identified in 78% of the retrieved discs. In contrast to the edge neovascularity observed in surgical specimens, capillaries were observed at the outer layer of AF surrounded by dense hyalinized and inactive-appearing collagen. From these results it is concluded that the blood vessels in extruded tissue from every type of herniation are newly formed, possibly through metaplasia of undifferentiated mesenchymal cells. It is also possible that they are derived from blood vessels that have invaded the AF as a result of disc degeneration. The finding of detection of progressive disc degeneration in both groups after 20-25 years seems to be of special interest because disc degeneration is a process that may not be directly correlated to disc herniation in these age groups.

Adolescent↗
PubMed1977

Lloyd Morgan's theory of instinct: from Darwinism to neo-Darwinism.

Darwin's proposal of two sources of instinct--natural selection and inherited habit--fostered among late nineteenth century evolutionists a variety of conflicting notions concerning the mechanisms of evolution. The British comparative psychologist C. Lloyd Morgan was a cardinal figure in restructuring the orthodox Darwinian conception to relieve the confusion besetting it and to meet the demands of the new biology of Weismann. This paper traces the development of Morgan's ideas about instinct against the background of his philosophic assumptions and the views of instinct theorists from Darwin and Romanes to McDougall and Lorenz.

Animals↗
PubMedDate not supplied

Acne: evolution of the clinical practice and therapeutic management of acne between 1996 and 2000.

According to epidemiological studies, acne is a common condition affecting 80% of young people between 12 and 18 years of age. It is also the most common reason for consultation in private dermatology practices. Yet, paradoxically, very few studies have been concerned with the profile and therapeutic treatment of acne patients. The aim of this study was to compare both the evolution of the profile of acne patients and the therapies used by dermatologists between 1996 and 2000 through a survey. Two questionnaires had to be filled in by the dermatologists for all patients consulting for acne, the first in 1996 and the second in 2000. The purpose of these questions was to obtain information about the demographic characteristics of the patients, a clinical evaluation of the patients' acne, their quality of life and finally their treatment. The statistical tests used Chi2 tests and variance analysis. The alpha risk was fixed at 0.05. Two thousand two hundred and eighty four patients were included in the survey in 1996 and 2363 in 2000. The mean age was 21 7.6 in 1996 and 20.5 7.7 in 2000, the majority of whom were female (64.4% in 1996 and 63.6% in 2000). In 1996 37.4% were students, and 52.4% in 2000. For 81.1% of the patients, the consultations were spontaneous on their own initiative both in 1996 and 2000. As regards topical treatment, a decrease of antibiotic prescriptions was noted between 1996 and 2000 associated with a decrease of benzoyl peroxyde use. Concerning the systemic treatments, an increase of doxycyclin and isotretinoin prescriptions was reported together with a decrease of minocycline treatment. Prescription of zinc salts and hormonal treatments were stable. The frequency of biological investigations remained similar and low. The repercussions of acne on the patient's quality of life were more numerous in 1996 compared to 2000 but they remained equally intense for those who reported them. The profile of acne patients evolved slightly between 1996 and 2000 and interestingly the treatments were modified to take into account the information in the literature such as bacterial resistance or severe side effects.

Acne Vulgaris↗
PubMed2001

Comparative context of Plio-Pleistocene hominin brain evolution.

One of the distinguishing features of Homo sapiens is its absolutely and relatively large brain. This feature is also seen in less extreme form in some fossil Homo species. However, are increases in brain size during the Plio-Pleistocene only seen in Homo, and is brain enlargement among Plio-Pleistocene primates confined to hominins? This study examines evidence for changes in brain size for species and lineage samples of three synchronic East African fossil primate groups, the two hominin genera Homo and Paranthropus, and the cercopithecoid genus Theropithecus. Hominin endocranial capacity data were taken from the literature, but it was necessary to develop an indirect method for estimating the endocranial volume of Theropithecus. Bivariate and multivariate regression equations relating measured endocranial volume to three external cranial dimensions were developed from a large (ca. 340) sample of modern African cercopithecoids. These equations were used to estimate the endocranial volumes of 20 Theropithecus specimens from the African Plio-Pleistocene. Spearman's rho and the Hubert nonparametric test were used to search for evidence of temporal trends in both the hominin and Theropithecus data. Endocranial volume apparently increased over time in both Homo and Paranthropus boisei, but there was no evidence for temporal trends in the endocranial volume of Theropithecus. Thus, hypotheses which suggest a mix of environmental, social, dietary, or other factors as catalysts for increasing brain in Plio-Pleistocene primates must accommodate evidence of brain enlargement in both Homo and Paranthropus, and explain why this phenomenon appears to be restricted to hominins.

Africa, Eastern↗
PubMed1992

The male reproductive organs in experimental Chagas' disease. II. Morphometric study of the vas deferens in the chronic phase of the disease.

A previous study showed that the vas deferens of mice in the acute phase of Chagas' disease had a slight increase in the muscle layer area associated with a small decrease in the luminal area. The vas deferens of chronic chagasic mice, investigated in the present experiment, presented a marked increase in the luminal area in addition to a significant thinning of the muscle and epithelium layers. The structural alterations of the vas deferens observed in the acute and chronic phases of Chagas' disease were compared with the evolution of chagasic esophagopathy.

Acute Disease↗
PubMed1990

Vocalizations of adult gelada baboons (Theropithecus gelada): acoustic structure and behavioural context.

Vocalizations and accompanying behaviors of adult gelada baboons were studied in four one-male groups kept in large outdoor enclosures in the zoos of Stuttgart and Rheine. Twenty-two acoustically different vocal patterns were determined. According to behavioural context, they were grouped into two categories: (1) contact calls and (2) aggressive and defensive calls. Frequency of calling and the production of different vocalizations were related to social rank and to the age of the sender. Vocalizations in species of the closely related genera Papio and Macaca are compared and their evolution is discussed.

Age Factors↗
PubMed1988

Evolution of Swan-Ganz catheter-related pulmonary valve nonbacterial endocarditis.

Invasive resuscitative and supportive therapy subsequent to accidental trauma, assault, or medical mishap may create lesions that forensic pathologists must interpret. Pulmonary valve nonbacterial endocarditis sometimes complicates placement of flow-directed pulmonary artery (Swan-Ganz) catheters. We examined ten cases of endocarditis from patients dying 0-10 days after removal of a Swan-Ganz catheter, and compared the natural evolution of vegetations in critically ill patients with the reported evolution of similar vegetations in experimental animals in the Freedman model. There was wide variation in macroscopic, as well as in the light- and scanning electron-microscopic, appearances in our cases and we could not establish a direct relationship between vegetation structure and time elapsed after removal of the catheter. These findings suggest that parameters related to critical illness and species account for the differences between this disease in human and animal models.

Catheterization, Swan-Ganz↗
PubMed1996

Comparative analysis of the cattle and human genomes: detection of ZOO-FISH and gene mapping-based chromosomal homologies.

Comparative chromosome painting with individual human chromosome-specific libraries (CSLs) on cattle metaphase chromosomes delineated 46 homologous chromosomal segments between the two species. Continuous arrangement of these segments on individual cattle chromosomes demonstrates a nearly complete coverage of the bovine karyotype and shows physical boundaries of bovine chromosomal segments homologous to individual human chromosomes. Alignment of the available comparative gene mapping data with the homologous segments strongly supports the detected gross homologies between the karyotypes of the two species. In addition to cattle, four human CSLs were hybridized to sheep metaphase chromosomes also, to further verify the known karyotype homology within the Bovidae. Besides its application to karyotype evolution research, the comparative knowledge provides for rapid expansion of the much needed Type I locus-based bovine gene map.

Animals↗
PubMed2026

Comparative genomic and proteomic analysis reveals orthogroup structured evolution of tick protease inhibitors.

Protease inhibitors (PIs) play central roles in regulating endogenous proteolysis and host-parasite interactions in ticks. However, the evolutionary architecture underlying their diversification across tick lineages remains insufficiently resolved. Here, we performed a genome-wide comparative analysis of predicted proteomes from 14 tick species to systematically characterize PI repertoires. In total, 4931 putative PIs were identified and grouped into 20 families using the MEROPS classification system. Further, PI families such as Antistasin, WAP-type, and Pacifastin, which have not previously been systematically reported in tick genomes, were classified. Orthogroup inference demonstrated that PI expansion is structured at the level of evolutionary lineages rather than uniformly across families. By stratifying orthogroups according to duplication burden and taxonomic conservation, we identified a broadly conserved single-copy core under strong purifying selection. Motif level analysis of serpin reactive center loops further revealed conservation of inhibitory specificity within single copy orthogroups and diversification of key functional residues in duplication-associated lineages. Integration of secretion prediction and tissue-resolved proteomics from Hyalomma anatolicum and Rhipicephalus microplus demonstrated that evolutionary stratification is reflected at the protein level. Together, these findings provide an orthogroup-resolved evolutionary framework linking duplication dynamics, molecular evolution, and tissue-level protein deployment. This integrative approach offers a systematic basis for prioritizing conserved and diversified PI lineages for future functional and anti-tick intervention studies.

Animals↗
PubMed1991

[Impaired fibrinolytic response to the venous occlusion test in patients with cryptogenic colitis].

The fibrinolytic response to venous occlusion was studied in 17 patients with inflammatory bowel disease: 7 with Crohn's disease, 10 with ulcerative colitis and compared with those obtained in 20 controls. Patients with inflammatory bowel disease showed decreased tissue-type plasminogen activator antigen release (t-PA Ag), no significant Von Willebrand antigen release (vWF Ag), and a residual plasminogen activator inhibitor activity (PAI activity) after venous occlusion. These modifications were more important in the evolutive colitis group compared with the remission group. Hypofibrinolysis, as defined by a defective t-PA release, and a residual PAI activity after venous occlusion might contribute to digestive and/or extra digestive thrombotic manifestations observed during the course of inflammatory bowel diseases.

Adult↗
PubMed2002

Prognostic accuracy of cerebral blood flow measurement by perfusion computed tomography, at the time of emergency room admission, in acute stroke patients.

The purpose of this study was to determine the prognostic accuracy of perfusion computed tomography (CT), performed at the time of emergency room admission, in acute stroke patients. Accuracy was determined by comparison of perfusion CT with delayed magnetic resonance (MR) and by monitoring the evolution of each patient's clinical condition. Twenty-two acute stroke patients underwent perfusion CT covering four contiguous 10mm slices on admission, as well as delayed MR, performed after a median interval of 3 days after emergency room admission. Eight were treated with thrombolytic agents. Infarct size on the admission perfusion CT was compared with that on the delayed diffusion-weighted (DWI)-MR, chosen as the gold standard. Delayed magnetic resonance angiography and perfusion-weighted MR were used to detect recanalization. A potential recuperation ratio, defined as PRR = penumbra size/(penumbra size + infarct size) on the admission perfusion CT, was compared with the evolution in each patient's clinical condition, defined by the National Institutes of Health Stroke Scale (NIHSS). In the 8 cases with arterial recanalization, the size of the cerebral infarct on the delayed DWI-MR was larger than or equal to that of the infarct on the admission perfusion CT, but smaller than or equal to that of the ischemic lesion on the admission perfusion CT; and the observed improvement in the NIHSS correlated with the PRR (correlation coefficient = 0.833). In the 14 cases with persistent arterial occlusion, infarct size on the delayed DWI-MR correlated with ischemic lesion size on the admission perfusion CT (r = 0.958). In all 22 patients, the admission NIHSS correlated with the size of the ischemic area on the admission perfusion CT (r = 0.627). Based on these findings, we conclude that perfusion CT allows the accurate prediction of the final infarct size and the evaluation of clinical prognosis for acute stroke patients at the time of emergency evaluation. It may also provide information about the extent of the penumbra. Perfusion CT could therefore be a valuable tool in the early management of acute stroke patients.

Acute Disease↗
PubMed1991

Molecular phylogeny of plethodonine salamanders and hylid frogs: statistical analysis of protein comparisons.

The bootstrapping method of determining confidence in the topology of phylogenetic trees has been applied to electrophoretic protein data for two groups of amphibians: salamanders of two North American genera (Aneides and Plethodon) of the tribe Plethodontini and Holarctic hylid frogs. Some current methods of phylogenetic reconstruction for electrophoretic protein data have been evaluated by comparing the trees obtained from molecular data sets with available morphological data. Molecular data on the phylogenetic relationships of Aneides and Plethodon, data obtained from electrophoretic and immunological studies, indicate that Aneides probably was derived from western Plethodon subsequent to the separation of eastern and western Plethodon. Thus Plethodon very likely is a paraphyletic genus. The extremely low rate of morphological evolution in Plethodon compared with that in Aneides causes difficulty in indicating their evolutionary relationships taxonomically because there are no synapomorphic morphological characters that define either eastern or western Plethodon, whereas there are several for the genus Aneides. Thus molecular data alone probably indicate the evolutionary relationships of the species in these genera. Highton and Larson's (1979) arrangement of species of Plethodon into eight species groups is supported. The topologies of the unweighted pair-group method using arithmetic means (UPGMA) and distance Wagner trees were compared with independent morphological and molecular data on the relationships of the 28 plethodonine species. It was found that UPGMA trees indicate relationships that are more in agreement with other information than are those provided by distance Wagner trees. The use of the bootstrap technique indicates that the topologies of UPGMA trees are better supported statistically than are the topologies of distance Wagner trees. Moreover, different addition criteria produce a variety of distance Wagner trees with different topologies, each with several groupings that are not supported statistically. It is concluded that considerable caution should be used in interpreting the topology of distance Wagner trees. Very similar results were obtained with a second data set on 30 taxa of Holarctic hylid frogs. Trees obtained by the neighbor-joining method are more in agreement with UPGMA phenograms and other data, so this method of phylogenetic reconstruction may be useful to systematists not willing to assume constant rates of evolution.(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acid Sequence↗
PubMed1979

Analysis of the constancy of DNA sequences during development and evolution of the nematode Caenorhabditis elegans.

In order to test for the occurrence of rearrangements in DNA during development and to assess the rate of DNA divergence during evolution, we have compared restriction fragments derived from DNA from four sources: sperm cells and somatic tissues of one strain of the nematode Caenorhabditis elegans, somatic tissues of a second strain of the same species, and whole animals of a closely related species. Restriction fragments were detected by hybridizing radioactive cloned fragments to restriction digests that had been fractionated by size on agarose gels and transferred to nitrocellulose sheets. In this way, approximately 50 BamHI restriction fragments were visualized and compared. Fragments from sperm and somatic DNAs were found to be identical; 15% differed in size between the two strains. Little cross homology was found between the two species. We conclude that, if rearrangements occur in C. elegans DNA during development, they must affect fewer than a few percent of the restriction fragments or restriction sites. The difference found between the two strains and the two species is surprisingly great.

Animals↗
PubMed1985

The myelodysplastic syndromes: different evolution patterns based on sequential morphological and cytogenetic investigations.

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)

Adult↗