[Evolution of the larynx from the viewpoint of comparative anatomy].
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Animals↗
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Phylogenetic analysis among the families of the Cyclophyllidea (Eucestoda) based on comparative morphology, with new hypotheses for co-evolution in vertebrates.
Phylogenetic analysis of the families of the Cyclophyllidea based on comparative morphology revealed support for monophyly of the order. Four equal length trees (CI = 0.71) resulted from analysis of 42 binary and multistate characters. Major conclusions are the following: (1) a basal position for the arostellate groups, with Mesocestoididae + Nematotaeniidae representing the basal subclade; (2) polyphyly for the Anoplocephalidae with sister-group associations postulated respectively for Anoplocephalinae + Thysanosomatinae and Linstowiinae + Inermicapsiferinae; (3) recognition within the rostellate cyclophyllideans of taeniid, dilepidid and davaineid subclades and the Dipylidiidae: (4) designation of Metadilepididae + Paruterinidae as sister taxa; (5) monophyly for the Davaineidae with all inclusive subfamilies; and (6) a close relationship for the Hymenolepididae and acoleate cyclophyllideans. Monophyly for such classically defined groups as the Mesocestoididae, Taeniidae and Davaineidae is corroborated. Polyphyly of the Dilepididae sensu lato, with independence of the Dipylidiidae, Dilepididae sensu Bona (1994), the Metadilepididae + Paruterinidae, and the Gryporhynchidae is confirmed. As presented these constitute testable hypotheses for monophyly and relationships among the families of the Cyclophyllidea. Initial diversification of the cyclophyllideans occurred in mammalian hosts and three independent events of colonisation of avian taxa are postulated. Origins of the cyclophyllideans extend into the Mesozoic or earlier, with extant taxa representing lineages that were persistent across the extinction event that defines the Cretaceous-Tertiary boundary.
Anatomy, Comparative↗
Analysis of corneal surface evolution after moderate alkaline burns by using impression cytology.
PURPOSE: To compare corneal surface evolution after moderate alkaline burns by impression cytology in patients treated with medical therapy or with amniotic membrane transplantation (AMT). METHODS: A prospective study of 24 eyes from 18 patients (13 men and 5 women) with moderate alkaline burns was performed. All patients were divided according to the clinical ocular severity and the therapy used. Twelve eyes were treated surgically with AMT and the other 12 eyes received only medical therapy. Corneal cytology was obtained immediately after the burns, and 1, 2, 5, and 9 months later. We differentiated between samples obtained from affected areas and areas not affected by the burns. Cellular size, nuclear size, and nuclear-cytoplasmic (N:C) ratio were examined in corneal epithelial cells, as was the presence of goblet cells in corneal epithelium. RESULTS: Nuclear size, cellular size, and N:C ratio in non-burn-affected corneal areas had no significant alterations in comparison with normal eyes. In contrast, in burn-affected corneal areas, these parameters were significantly worse, and the presence of goblet cells in corneal epithelium was frequent 1 month after severe burns. Cellular size, nuclear size, N:C ratio, and corneal conjunctivalization improved during the study in all patients, but corneal reepithelialization occurred earlier in patients treated with AMT than in patients with only medical therapy. CONCLUSION: Morphologic and morphometric analysis of corneal cells by impression cytology after ocular burns permits the establishment of cellular reepithelialization patterns in relation with limbal deficiency level and with clinical ocular severity. AMT improves corneal reepithelialization earlier than medical therapy in moderate alkaline burns.
Alkalies↗
[Karyotypic evolution in man and chimpanzees. A comparative study of band topographies after controlled denaturation].
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Animals↗
Extreme differences in charge changes during protein evolution.
The maintenance of a proper distribution of charged amino acid residues might be expected to be an important factor in protein evolution. We therefore compared the inferred changes in charge during the evolution of 43 protein families with the changes expected on the basis of random base substitutions. It was found that certain proteins, like the eye lens crystallins and most histones, display an extreme avoidance of changes in charge. Other proteins, like phospholipase A2 and ferredoxin, apparently have sustained more charged replacements than expected, suggesting a positive selection for changes in charge. Depending on function and structure of a protein, charged residues apparently can be important targets for selective forces in protein evolution. It appears that actual biased codon usage tends to decrease the proportion of charged amino acid replacements. The influence of nonrandomness of mutations is more equivocal. Genes that use the mitochondrial instead of the universal code lower the probability that charge changes will occur in the encoded proteins.
Biological Evolution↗
Enlarged similarity of nucleic acid sequences.
The concept of nucleic acid sequence base alternations is presented. The number of base alterations for the sequences of different length is established. The definition of "enlarged similarity" of nucleic acids sequences on the basis of sequence base alterations is introduced. Mutual information between sequences is used as a quantitative measure of enlarged similarity for two compared sequences. The method of mutual information calculation is developed considering the correlation of bases in compared sequences. The definitions of correlated similarity and evolution similarity between compared sequences are given. Results of the use of enlarged similarity approach for DNA sequences analysis are discussed.
Base Sequence↗
Comparative analysis and insights into the evolution of gene clusters for glycopeptide antibiotic biosynthesis.
The bal, cep, dbv, sta and tcp gene clusters specify the biosynthesis of the glycopeptide antibiotics balhimycin, chloroeremomycin, A40926, A47934 and teicoplanin, respectively. These structurally related compounds share a similar mechanism of action in their inhibition of bacterial cell wall formation. Comparative sequence analysis was performed on the five gene clusters. Extensive conserved synteny was observed between the bal and cep clusters, which direct the synthesis of very similar compounds but originate from two different species of the genus Amycolatopsis. All other cluster pairs show a limited degree of conserved synteny, involving biosynthetically functional gene cassettes: these include those involved in the synthesis of the carbon backbone of two non-proteinogenic amino acids; in the linkage of amino acids 1--3 and 4--7 in the heptapeptide; and in the formation of the aromatic cross-links. Furthermore, these segments of conserved synteny are often preceded by conserved intergenic regions. Phylogenetic analysis of protein families shows several instances in which relatedness in the chemical structure of the glycopeptides is not reflected in the extent of the relationship of the corresponding polypeptides. Coherent branchings are observed for all polypeptides encoded by the syntenous gene cassettes. These results suggest that the acquisition of distinct, functional genetic elements has played a significant role in the evolution of glycopeptide gene clusters, giving them a mosaic structure. In addition, the synthesis of the structurally similar compounds A40926 and teicoplanin appears as the result of convergent evolution.
Actinomycetales↗
[ATC and EphMRA classifications: evolution from 1996 to 2003 and comparative analysis].
In their daily practice, health practitioners use one or more pharmacotherapeutic classifications. This diversity of classifications impairs the exchange of drug information, while the use of international or European classifications facilitates this diffusion. The "Hospital National Center of Drugs Information" (CNHIM) has integrated ATC (Anatomical Therapeutic Chemical) and EphMRA (European Pharmaceutical Marketing Research Association) classifications into its "Thériaque" database and has given the ATC official status in France by publishing a French translation. The objective of this article was to analyse the evolution of these two classification systems between 1996 and 2003, and to compare their allocations (of codes) with those for the drugs present in Thériaque in January 2002. The ATC comprises 14 principal groups and five levels of hierarchy, while the EphMRA comprises 16 principal groups and three to four levels. In Thériaque, the ATC is linked to active substances and drugs, and the EphMRA to drugs. Data-processing requests have made it possible to make a comparative analysis. Each year, the two classification systems evolve in terms of addition, suppression, modification and subdivision. Two principal differences are evident in the allocations in Thériaque (class EphMRA K "Hospital solutions" versus class ATC B "Blood and blood forming organ"; class EphMRA T "Diagnostic agents" versus class ATC V "Various"). Classifications evolve in parallel or independently, and although they are closely related to one another, they retain their specificities in terms of structure and uses.
Drug Information Services↗
Correlated evolution of male and female morphologles in water striders.
Sexually antagonistic coevolution may be an important force in the evolution of sexual dimorphism. We undertake a comparative study of correlated evolution of male and female morphologies in a clade of 15 water strider species in the genus Gerris (Heteroptera: Gerridae). Earlier studies have shown that superfluous matings impose costs on females, including increased energetic expenditure and predation risk, and females therefore resist males with premating struggles. Males of some species possess grasping structures and females of some species exhibit distinct antigrasping structures, which are used to further the interests of each sex during these premating struggles. We use this understanding, combined with coevolutionary theory, to derive a series of a priori predictions concerning both the types of traits in the two sexes that are expected to coevolve and the coevolutionary dynamics of these traits expected under sexually antagonistic coevolution. We then assess the actual pattern of correlated evolution in this clade with new morphometric methods combined with standard comparative techniques. The results were in agreement with the a priori predictions. The level of armament (different abdominal structures in the two sexes) was closely correlated between the sexes across species. Males are well adapted to grasping females in species in which females are well adapted to thwart harassing males and vice versa. Furthermore, our comparative analyses supports the prediction that correlated evolution of armament in the two sexes should be both rapid and bidirectional.
Animals↗
The evolution of Runx genes I. A comparative study of sequences from phylogenetically diverse model organisms.
BACKGROUND: Runx genes encode proteins defined by the highly conserved Runt DNA-binding domain. Studies of Runx genes and proteins in model organisms indicate that they are key transcriptional regulators of animal development. However, little is known about Runx gene evolution. RESULTS: A phylogenetically broad sampling of publicly available Runx gene sequences was collected. In addition to the published sequences from mouse, sea urchin, Drosophila melanogaster and Caenorhabditis elegans, we collected several previously uncharacterised Runx sequences from public genome sequence databases. Among deuterostomes, mouse and pufferfish each contain three Runx genes, while the tunicate Ciona intestinalis and the sea urchin Strongylocentrotus purpuratus were each found to have only one Runx gene. Among protostomes, C. elegans has a single Runx gene, while Anopheles gambiae has three and D. melanogaster has four, including two genes that have not been previously described. Comparative sequence analysis reveals two highly conserved introns, one within and one just downstream of the Runt domain. All vertebrate Runx genes utilize two alternative promoters. CONCLUSIONS: In the current public sequence database, the Runt domain is found only in bilaterians, suggesting that it may be a metazoan invention. Bilaterians appear to ancestrally contain a single Runx gene, suggesting that the multiple Runx genes in vertebrates and insects arose by independent duplication events within those respective lineages. At least two introns were present in the primordial bilaterian Runx gene. Alternative promoter usage arose prior to the duplication events that gave rise to three Runx genes in vertebrates.
Amino Acid Sequence↗
Experimental evolution of propanediol oxidoreductase in Escherichia coli. Comparative analysis of the wild-type and mutant enzymes.
A model for the study of experimental evolution is provided by the novel metabolic system responsible for the progressive utilization of L-1,2-propane-diol by mutants of Escherichia coli (strains 3 and 430). In these mutant strains, propanediol oxidoreductase, which serves as L-lactaldehyde reductase in fucose fermentation by wild-type cells, became a key enzyme for aerobic catabolism of propanediol. In the wild-type strain (strain 1), the enzyme is inducible only anaerobically; in strains 3 and 430, the enzyme is synthesized constitutively even in the presence of air. The propanediol oxidoreductase from all three strains was purified to homogeneity by the same procedure. The enzyme of strain 3 clearly differed from that of strain 1 in several respects: Km and V in both directions of the reaction, energy of activation, thermal stability, pH optimum and substrate specificity. However, no difference in any of the above characteristics was found between the enzymes of strains 3 and 430. All three enzymes presented the same electrophoretic mobility. According to immunological data, all three strains differed in their intracellular enzyme level.
Alcohol Oxidoreductases↗
Utilization of Inorganic Carbon by Ulva lactuca.
Thalli discs of the marine macroalga Ulva lactuca were given inorganic carbon in the form of HCO(3) (-), and the progression of photosynthetic O(2) evolution was followed and compared with predicted O(2) evolution as based on calculated external formation of CO(2) (extracellular carbonic anhydrase was not present in this species) and its carboxylation (according to the K(m)(CO(2)) of ribulose-1,5-bisphosphate carboxylase/oxygenase), at two different pHs, assuming a photosynthetic quotient of 1. The K(m)(inorganic carbon) was some 2.5 times lower at pH 5.6 than at the natural seawater pH of 8.2, whereas V(max) was similar under the two conditions, indicating that the unnaturally low pH per se had no adverse effect on U. lactuca's photosynthetic performance. These results, therefore, could be evaluated with regard to differential CO(2) and HCO(3) (-) utilization. The photosynthetic performance observed at the lower pH largely followed that predicted, with a slight discrepancy probably reflecting a minor diffusion barrier to CO(2) uptake. At pH 8.2, however, dehydration rates were too slow to supply CO(2) for the measured photosynthetic response. Given the absence of external carbonic anhydrase activity, this finding supports the view that HCO(3) (-) transport provides higher than external concentrations of CO(2) at the ribulose-1,5-bisphosphate carboxylase/oxygenase site. Uptake of HCO(3) (-) by U. lactuca was further indicated by the effects of potential inhibitors at pH 8.2. The alleged band 3 membrane anion exchange protein inhibitor 4,4'-diisothiocyanostilbene-2,2'disulphonate reduced photosynthetic rates only when HCO(3) (-) (but not CO(2)) could be the extracellular inorganic carbon form taken up. A similar, but less drastic, HCO(3) (-)-competitive inhibition of photosynthesis was obtained with Kl and KNO(3). It is suggested that, under ambient conditions, HCO(3) (-) is transported into cells at defined sites either via facilitated diffusion or active uptake, and that such transport is the basis for elevated internal [CO(2)] at the site of ribulose-1,5-bisphosphate carboxylase/oxygenase carboxylation.
Journal Article↗
Evolution and significance of circulating procalcitonin levels compared with IL-6, TNF alpha and endotoxin levels early after thermal injury.
To determine the evolution and significance of circulating procalcitonin (ProCT), IL-6 TNF alpha and endotoxin levels early after thermal injury, we performed a prospective, single unit, longitudinal study. Forty burn patients with total body surface area (TBSA) > 30 per cent were studied, of whom 33 suffered an inhalation injury. Blood samples were taken on the day of admission, every 4 h during the first day and daily during the first week. All patients had increased ProCT and IL-6 levels without any proven infection. Endotoxin and TNF alpha levels remained very low or undetectable. ProCT and IL-levels correlated well with the severity of skin burn injury (respectively, p < 0.006 and p < 0.028, using the non-parametric Kruskal-Wallis test). ProCT levels are not associated with smoke inhalation. ProCT and IL6 are prognostic factors of mortality at the time of admission but less reliable than the clinical UBS (unit burn standard) score. Endotoxin and TNF alpha were undetectable, suggesting that the problem of the early gut bacterial translocation remains to be proven.
Adult↗
The evolution of human longevity.
In the comparatively short history of human evolution man's lifespan has doubled, posing the question, by what means was this prolongation of life achieved. One line of thought correlates lifespan with oxygen consumption and energy generation, pointing out that small homeothersms which expend energy at a very high rate, are invariable short lived, while animals living more economically in terms of energy expenditure, like some heterotherms and large homeotherms, can attain greatly increased lifespan potentials. The correlation between lifespan and energy expenditure is generally valid, but some animals with low energy needs, notably tropical animals and some lethargic, inactive animals, do not live as long as expected on the basis of the theory. The present paper suggest that the aging process could be accelerated by hyperthermia and the longevity of some homeotherms, beside its connection with energy needs, could also be correlated with the evolution of temperature regulating mechanisms, resulting in more accurate thermal homeostasis. Man's uniquely capacious sweating mechanism, for example, may play a part in the attainment of his long life.
Aging↗
Evaluation of the clinical benefit of permixon and tamsulosin in severe BPH patients-PERMAL study subset analysis.
OBJECTIVE: To compare the efficacy of the lipido-sterolic extract of Serenoa repens, Permixon, to that of the alpha-blocker, tamsulosin, in the treatment of severe low urinary tract symptoms (LUTS) of benign prostatic hyperplasia (BPH). METHODS: In a 12-month, double-blind, randomized study that showed equivalent efficacy of Permixon 320 mg/day and tamsulosin 0.4 mg/day ("PERMAL study"), 685 BPH patients with IPSS > or =10 had been analyzed for efficacy. Of these, the 124 patients with severe LUTS (IPSS >19) at randomization were retained for this subset analysis. After a 4-week run-in period, 59 and 65 patients had been randomized to tamsulosin and Permixon groups, respectively. Both treatment groups were compared regarding the evolution from baseline of total IPSS and its irritative and obstructive subscores, LUTS-related QoL, prostate volume, Q(max) and MSF-4 (sexual activity questionnaire) at different time points over 1 year. An analysis of variance of changes from baseline to end point was performed for all the parameters. The over-time evolutions of total, irritative and obstructive IPSS were further compared using a variance analysis for repeated measurements. RESULTS: At 12 months, total IPSS decreased by 7.8 with Permixon and 5.8 with tamsulosin (p=0.051); the irritative symptoms improved significantly more (p=0.049) with Permixon (-2.9 versus -1.9 with tamsulosin). The superiority of Permixon in reducing irritative symptoms appeared as soon as month 3 and was maintained up to month 12 (p=0.03). CONCLUSION: Permixon 320 mg/day was shown to be slightly superior to tamsulosin 0.4 mg/day in reducing LUTS in severe BPH patients after 3 months and up to 12 months of treatment.
Adrenergic alpha-Antagonists↗
[Evaluation of the clinical benefit of Permixon and tamsulosin in severe BPH patients--PERMAL study subset analysis].
OBJECTIVE: To compare the efficacy of the lipido-sterolic extract of Serenoa repens, Permixon, to that of the a-blocker, tamsulosin, in the treatment of severe low urinary tract symptoms (LUTS) of benign prostatic hyperplasia (BPH). METHODS: In a 12-month, double-blind, randomized study that showed equivalent efficacy of Permixon 320 mg/day and tamsulosin 0.4 mg/day ("PERMAL study"), 685 BPH patients with IPSS > 10 had been analyzed for efficacy. Of these, the 124 patients with severe LUTS (IPSS > 19) at randomization were retained for this subset analysis. After a 4-week run-in period, 59 and 65 patients had been randomized to tamsulosin and Permixon groups, respectively. Both treatment groups were compared regarding the evolution from baseline of total IPSS and its irritative and obstructive subscores. LUTS-related QpL, prostate volume, Qmax and MSF-4 (sexual activity questionnaire) at different time points over 1 year An analysis of variance of changes from baseline to end point was performed for all the parameters. The over-time evolutions of total, irritative and obstructive IPSS were further compared using a variance analysis for repeated measurements. RESULTS: At 12 months, total IPSS decreased by 7.8 with Permixon and 5.8 with tamsulosin (p = 0.051); the irritative symptoms improved significantly more (p = 0.049) with Permixon (- 2.9 versus - 1.9 with tamsulosin). The superiority of Permixon in reducing irritative symptoms appeared as soon as month 3 and was maintained up to month 12 (p = 0.03). CONCLUSION: Permixon 320 mg/day was shown to be slightly superior to tamsulosin 0.4 mg/day in reducing LUTS in severe BPH patients after 3 months and up to 12 months of treatment.
Adrenergic alpha-Antagonists↗
Intervening sequences in paralogous genes: a comparative genomic approach to study the evolution of X chromosome introns.
The enlargement of the genome size and the decrease in genome compactness with increase in the number and size of introns is a general pattern during the evolution of eukaryotes. Among the possible mechanisms for modifying intron size, it has been suggested that the insertion of transposable elements might have an important role in driving intron evolution. The analysis of large portions of the human genome demonstrated that a relatively recent (50 to 100 MYA) accumulation of transposable elements appears to be biased, favoring a preferential insertion of LINE1 transposons into sex chromosomes rather than into autosomes. In the present work, the effect of chromosomal location on the increase in size of introns was evaluated with a comparative analysis performed on pairs of human paralogous genes, one located on the X chromosome and the second on an autosome. A phylogenetic analysis was also performed on the X-encoded proteins and their paralogs to confirm orthology-paralogy and to approximately estimate the time of gene duplication. Statistical analysis of total intron length for each pair of paralogous genes provided no evidence for a larger size of introns in the gene copies located on the X chromosome. On the opposite, introns of autosomal genes were found to be significantly longer than introns of their X-linked paralogs. Likewise, LINE1 elements were not significantly more frequent in X-chromosome introns, whereas the frequency of SINE elements showed a marginally significant bias toward autosomal introns.
Animals↗
Evolution of longevity in animals. A comparative approach. Proceedings of the 34th Brookhaven Symposium in Biology on Aging processes in animals. October 19-22, 1986, Upton, New York. Dedicated to George Sacher.
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Aging↗