[Evolution of 3 cases of glomerulonephritis of acute and oliguric evolution, treated by dialysis].
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Acute Disease↗
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Results for “evolution”
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[Retrospective study of the evolution of rheumatoid arthritis in children in its different forms and methods of treatment in the USSR and USA (a comparative study of the clinical aspects and evolution of the disease in the USSR and USA)].
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Adolescent↗
[Interactions of infants with adults in day care centers. Evolutive dependencies vs. counter-evolutive risks and characteristics of the mother-infant relationship].
As part of a broader research project on the construction of the self, six infants were observed longitudinally in day-care centers between the ages of five months and three years. Interviews were conducted with the six mothers in order to evaluate the intersubjective characteristics of the mother-infant relationship. For three of the six children, the mother was a caregiver in the center. This article deals with "propping" processes, defined as the affective-cognitive transformations by means of which infants develop networks of links with and between external and internal objects which are used for support during development and serve as a relay of the maternal object. The present analysis is limited to propping on the adults in the day-care center (caregivers, observer, and, for three of the children, mothers). Two factors were considered: the intersubjective quality of the mother-infant relation, and the presence or absence of the mother as a caregiver in the day-care center. The results showed that (1) even when very young, the infants under observation differentiated between the various functions of the adults, and adapted their behavior to them; (2) each child exhibited a unique and sometimes very creative way of using dependencies on an adult's psychic apparatus to construct his or her own modes of psychic functioning; and (3) the developmental dynamics and the richness of the observed transformations were found to depend on the quality of the contact and distancing in the mother-infant relationship and on the concrete conditions for its actualization, which can either promote or hinder, and sometimes even block, the construction of the mother's absence.
Adult↗
Evolution of the Joint National Committee reports, 1988-1997. Evolution of the science of treating hypertension.
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Cardiovascular Diseases↗
[Evolutionary histology and the theory of evolution (on the 100th anniversary of the birth of Academician A. A. Zavarzin].
Darwin's theory did not touch upon the problem of evolution of tissues. An attempt made by Heckel to explain phylogeny of tissues, basing on principles of selection and divergence, failed. It was not at once understood that evolution of separate levels of organization possessed certain specificity. The theory of parallelism, suggested by A. A. Zavarzin, stated the notion on specific regularities in evolution of tissues. Having analysed the correlation between the theory of evolution and evolutional histology, A. A. Zavarzin demonstrated that darwinism developed predominantly at the theory of speciation. This approach is correct for the period of the new evolutionary synthesis, too. The synthetic theory of evolution does not take into consideration evolution of tissues. A. A. Zavarzin's theory contributed to reorganization of methodology of the evolutional biology. The historical method was enriched by a certain principle on specific regularities of evolution for each level of organization in the alive. Simultaneously, the genesis of the parallelism theory discovered that correct explanation of the regularities in evolution of tissues is possible only under conditions that the evolution of histostructures can be inserted into the evolution of ontogenesis and species.
Biological Evolution↗
Effect of pH on chloroplast photosynthesis. Inhibition of O2 evolution by inorganic phosphate and magnesium.
1. The pH optimum of CO2-dependent O2 evolution by barley (Hordeum vulgare L.) chloroplasts was found to be between 7.8 and 8.2. The addition of 1 mM MgCl2 in the dark inhibited O2 evolution over the entire pH range tested and resulted in a much sharper pH profile centered around pH 8.2. 2. The pH optimum for O2 evolution, in the presence and absence of 1 mM MgCl2, was acid-shifted 0.3--0.4 pH units by 2 mM NH4Cl. The pH optimum of O2 evolution, with and without 1 mM MgCl2, was base-shifted by 2 mM sodium acetate, approx. 0.5 pH units relative to the controls. 3. O2 evolution in the presence of bicarbonate plus 3-phosphoglycerate or ribose-5-phosphate was considerably less sensitive to pH than CO2-dependent O2 evolution in the absence of substrate. With these substrates, both in the presence and absence of 1 mM MgCl2, the pH optimum was broad and was centered around pH 7.8. 4. Inhibition of CO2-dependent O2 evolution by inorganic phosphate and magnesium increased as the pH of the reaction mixture was decreased below the optimum. Decreasing the pH from 8.2 to 7.6, reduced over 3-fold the concentration of inorganic phosphate required to inhibit O2 evolution completely. For magnesium, a similar change in pH reduced the concentration required to inhibit O2 evolution 50% approx. 5-fold. At pH 8.2, magnesium inhibition required inorganic phosphate. Magnesium was not required for inhibition of O2 evolution by inorganic phosphate, but incresaed the relative inhibition observed. 5. Illumination of intact barley chloroplasts increased the activity of NADP-glyceraldehyde-3-P dehydrogenase, phosphoribulokinase and fructose-1,6-diphosphatase. MgCl2 and inorganic phosphate prevented this increase in enzyme activity at concentrations that completely inhibited CO2-dependent O2 evolution. 6. The results obtained suggest that magnesium inhibition of O2 evolution may be caused by enhanced phosphate exchange across the chloroplast envelope.
Chloroplasts↗
Suppression of cytogenetic clonal evolution with interferon alfa therapy in patients with Philadelphia chromosome-positive chronic myelogenous leukemia.
PURPOSE: To investigate whether cytogenetic clonal evolution can be suppressed with interferon alfa (IFN-alpha) therapy in patients with chronic myelogenous leukemia (CML). PATIENTS AND METHODS: Ninety patients with CML and cytogenetic clonal evolution who received IFN-alpha-based regimens were analyzed. Clonal evolution was defined as the presence of karyotypic abnormalities in addition to the Philadelphia (Ph) chromosome. Patients were evaluated for the suppression of cytogenetic clonal evolution after therapy, the cytogenetic response, and survival. RESULTS: The median age of the population was 39 years (range, 15 to 70 years), median time from diagnosis to clonal evolution 14 months (range, 0 to 145 months), and median percentage of abnormal metaphases 18% (range, 4% to 100%). Fifty six patients (62%) achieved some suppression of cytogenetic clonal evolution; in 41 patients (46%), the suppression was complete. The overall median survival was 51 months, with 43% alive at 5 years. Patients who achieved a complete suppression of cytogenetic clonal evolution had a median survival of 66 months, with 51% alive at 5 years. Characteristics associated with a better response include a lower percentage of abnormal metaphases, time to cytogenetic clonal evolution of 24 months or less, and absence of other features of accelerated disease. A prognostic classification for cytogenetic clonal evolution defined three groups with complete response (CR) rates of 85%, 34%, and 0% (P < .0001) and median survival times of 58, 31, and 30 months, respectively (P=.02). CONCLUSION: Patients with cytogenetic clonal evolution can respond to IFN-alpha therapy, and this response is associated with longer survival. A previously described prognostic model separates patients into subsets with different probabilities of response to IFN-alpha and survival.
Adolescent↗
Evolution of neurotransmitter receptor systems.
The presence of hormones, neurotransmitters, their receptors and biosynthetic and degradative enzymes is clearly not only associated with the present and the recent past but with the past several hundred million years. Evidence is mounting which indicates substantial conservation of protein structure and function of these receptors and enzymes over these tremendous periods of time. These findings indicate that the evolution and development of the nervous system was not dependent upon the formation of new or better transmitter substances, receptor proteins, transducers and effector proteins but involved better utilization of these highly developed elements in creating advanced and refined circuitry. This is not a new concept; it is one that is now substantiated by increasingly sophisticated studies. In a 1953 article discussing chemical aspects of evolution (Danielli, 1953) Danielli quotes Medawar, "... endocrine evolution is not an evolution of hormones but an evolution of the uses to which they are put; an evolution not, to put it crudely, of chemical formulae but of reactivities, reaction patterns and tissue competences." To also quote Danielli, "In terms of comparative biochemistry, one must ask to what extent the evolution of these reactivities, reaction patterns and competences is conditional upon the evolution of methods of synthesis of new proteins, etc., and to what extent the proteins, etc., are always within the synthetic competence of an organism. In the latter case evolution is the history of changing uses of molecules, and not of changing synthetic abilities." (Danielli, 1953). Figure 4 outlines a phylogenetic tree together with an indication of where evidence exists for both the enzymes that determine the biosynthesis and metabolism of the cholinergic and adrenergic transmitters and their specific cholinergic and adrenergic receptors. This figure illustrates a number of important points. For example, the evidence appears to show that the transmitters and their associated enzymes existed for a substantial period before their respective receptor proteins. While the transmitters and enzymes appear to exist in single cellular organisms, there is no solid evidence for the presence of adrenergic or cholinergic receptors until multicellular organisms where the receptors appear to be clearly associated with specific cellular and neuronal communication (Fig. 4). One can only speculate as to the possible role for acetylcholine and the catecholamine in single cell organisms.(ABSTRACT TRUNCATED AT 400 WORDS)
Animals↗
Genetic variation: molecular mechanisms and impact on microbial evolution.
On the basis of established knowledge of microbial genetics one can distinguish three major natural strategies in the spontaneous generation of genetic variations in bacteria. These strategies are: (1) small local changes in the nucleotide sequence of the genome, (2) intragenomic reshuffling of segments of genomic sequences and (3) the acquisition of DNA sequences from another organism. The three general strategies differ in the quality of their contribution to microbial evolution. Besides a number of non-genetic factors, various specific gene products are involved in the generation of genetic variation and in the modulation of the frequency of genetic variation. The underlying genes are called evolution genes. They act for the benefit of the biological evolution of populations as opposed to the action of housekeeping genes and accessory genes which are for the benefit of individuals. Examples of evolution genes acting as variation generators are found in the transposition of mobile genetic elements and in so-called site-specific recombination systems. DNA repair systems and restriction-modification systems are examples of modulators of the frequency of genetic variation. The involvement of bacterial viruses and of plasmids in DNA reshuffling and in horizontal gene transfer is a hint for their evolutionary functions. Evolution genes are thought to undergo biological evolution themselves, but natural selection for their functions is indirect, at the level of populations, and is called second-order selection. In spite of an involvement of gene products in the generation of genetic variations, evolution genes do not programmatically direct evolution towards a specific goal. Rather, a steady interplay between natural selection and mixed populations of genetic variants gives microbial evolution its direction.
Bacteria↗
[Molecular bases of evolution].
The general notions of the theory of evolution are listed. The unity of the "engineering principles" of the living nature is emphasized. The generalists and specialists species are discussed. The estimation of their evolution rates must be different if it is expressed by the number of species or by the morphological changes. The principles of "protein engineering" of the organisms and the role of metals in protein evolution are discussed. It is suggested that in the presence of ions of transition metals and zinc the Fox's proteinoids can possess more specific forms of enzymatic activity. In the evolution of language the horizontal transfer plays a much more important role than in the biological evolution. However in this case also the initial basis of the language remains. The random drift is considered and it is shown that in concordance with the neutralist theory there are no grounds to replace the calculation of the rates of mutational changes per time unity by the calculation per generation. The molecular drive is the main source of the evolutionary novelties. The drive is connected with drift. The synonymic mutations and the mutations in non-functional DNA are evolutionary important. The future mathematical theory of evolution must be based on the theory of Markov's chains with the stochastic matrix changing along the chain and containing the set of the non-diagonal members equal to zero. The results obtained in the theory of ontogeny are presented. The evolution of species is the evolution of ontogenies, the formation of the molecular theory of evolution can be possible only on the basis of the molecular theory of ontogeny. The internal causes of extinction of species reduce the accumulation of neutral and pseudo-neutral mutations.
Animals↗
Experimental evolution reveals contrasting adaptive landscapes in lab and field environments.
Experimental evolution is widely used to infer microbial responses to environmental change, yet most laboratory studies impose constant, well-mixed conditions that differ fundamentally from fluctuating, spatially structured field environments. We compared genomic evolution in the leaf litter-associated bacterium Curtobacterium strain MMLR14_002 under control and warming treatments in laboratory culture and in a complementary field experiment. Laboratory-derived isolates accumulated more mutations per genome and exhibited stronger locus-level parallelism, with mutations recurring in a small number of coding loci. Field-derived isolates accumulated fewer mutations per genome, and these mutations rarely occurred in the same coding loci across replicate populations. Instead, field isolates exhibited a higher proportion of intergenic mutations, with mutations recurring in the same intergenic regions across independent field deployments. When coding mutations were detected in the field, they were distributed across functionally diffuse targets and more often involved metabolic pathways than the core cellular processes repeatedly targeted during laboratory evolution. Warming itself did not consistently influence mutation accumulation or the genomic distribution of mutations; instead, laboratory and field contexts primarily shaped the accumulation, targets, and repeatability of genomic change. These results suggest that laboratory thermal evolution identifies adaptive routes favored under sustained selection but may overestimate coding-level parallelism under heterogeneous field conditions. Bridging laboratory and field evolution will likely require experimental designs that incorporate temporal variability and spatial heterogeneity characteristic of natural systems.IMPORTANCEA central goal of experimental evolution is to infer how microbes evolve in nature from laboratory studies. Here, we evaluate this assumption by comparing genomic evolution of a leaf litter-associated Curtobacterium strain in laboratory and field warming experiments to identify broad patterns rather than isolate the contribution of any single environmental factor. We find that the strong parallelism at coding loci observed under laboratory conditions is reduced in the field, while mutations recurring in the same intergenic regions across field deployments suggest that parallel evolution in nature may more often involve regulatory noncoding regions rather than coding targets. These results show that environmental context reshapes adaptive landscapes and may limit the parallelism of coding-level genomic responses inferred from homogeneous laboratory conditions.
experimental evolution↗
Molecular evolution of the polypeptide hormones.
Any biological function is at least bimolecular and its evolution therefore is at least dual, with variations in two lines of molecules. The hormone specificity results from a particular fit between the three-dimensional structure of the agent and that of the receptor but, because receptors are not known at the structural level, a discussion on the evolution of the polypeptide hormones is mainly limited to the possible progressive changes of the latter. As for other proteins (enzymes, oxygen carriers etc.) two degrees of complexity can be distinguished according to whether the hormone comprises one or several polypeptide chains. Protein assembly can bring new biological properties, each subunit playing a particular role. In this case, the 'internal' evolution (chain-chain interactions) overlaps the 'external' evolution (hormone-receptor contacts). The 'monomeric' hormones present the following problems: evolution of the prohormone and of the converting enzyme (for insulin), duplication and differentiation of two lines of hormones either by amino acid substitutions (neurohypophysial hormones and neurophysins) or by substitutions and size modifications (corticotropin and lipotropin), duplication and fusion leading to internal homology in the single polypeptide chain (somatotropin, prolactin, placental lactogen). The 'dimeric' hormones lead to several problems: successive duplications giving different subunits, selective associations between subunits, unequal rates of evolution of the subunits, the function of each subunit (lutropin, follitropin, thyrotropin, choriogonadotropin). An attempt is made to integrate the evolution of polypeptide hormones in the frame of the evolution of proteins.
Amino Acid Sequence↗
The evolution of sexes.
It is very likely that sexual differentiation into two morphologically indistinguishable mating types has preceded the evolution of anisogamy. Therefore, the study of the evolution of mating types in an isogamous population is more informative for understanding the forces responsible for the evolution of different sexes than the study of the evolution of anisogamy; the latter represents the secondary problem of how, after the establishment of two sexes, an increasing degree of gamete dimorphism may evolve. Mating type evolution has been analyzed theoretically in population genetic models. These explorations show that mating types may evolve as a consequence of selection for more efficient gamete recognition, and also as a result of intragenomic conflict between nuclear and cytoplasmic DNA. However, in both cases the selection forces have to be very strong, which makes these possible explanations less convincing. Nearly all theories proposed for the evolution of anisogamy assume two conflicting selection forces to be relevant: selection for greater gamete productivity, and selection for greater zygote size. Although the explanation is intuitively plausible, the comparative evidence is a bit disappointing. Alternatively, anisogamy can be explained as a side-effect of selection for a greater efficiency in finding a mating partner by using sexual pheromones. Firm empirical evidence is lacking, however. In both problem areas--mating type evolution and anisogamy evolution--experimental work is badly needed.
Animals↗
A molecular description of the evolution of resistance.
BACKGROUND: In vitro evolution has been used to obtain nucleic acid molecules with interesting functional properties. The evolution process usually is carried out in a stepwise manner, involving successive rounds of selection, amplification and mutation. Recently, a continuous in vitro evolution system was devised for RNAs that catalyze the ligation of oligonucleotide substrates, allowing the evolution of catalytic function to be studied in real time. RESULTS: Continuous in vitro evolution of an RNA ligase ribozyme was carried out in the presence of a DNA enzyme that was capable of cleaving, and thereby inactivating, the ribozyme. The DNA concentration was increased steadily over 33.5 hours of evolution, reaching a final concentration that would have been sufficient to inactivate the starting population in one second. The evolved population of ribozymes developed resistance to the DNA enzyme, reducing their vulnerability to cleavage by 2000-fold but retaining their own catalytic function. Based on sequencing and kinetic analysis of the ribozymes, two mechanisms are proposed for this resistance. One involves three nucleotide substitutions, together with two compensatory mutations, that alter the site at which the DNA enzyme binds the ribozyme. The other involves enhancement of the ribozyme's ability to bind its own substrate in a way that protects it from cleavage by the DNA enzyme. CONCLUSIONS: The ability to direct the evolution of an enzyme's biochemical properties in response to the behavior of another macromolecule provides insight into the evolution of resistance and may be useful in developing enzymes with novel or enhanced function.
Base Sequence↗
Variable rates of SARS-CoV-2 evolution in chronic infections.
An important feature of the evolution of the SARS-CoV-2 virus has been the emergence of highly mutated novel variants, which are characterised by the gain of multiple mutations relative to viruses circulating in the general global population. Cases of chronic viral infection have been suggested as an explanation for this phenomenon, whereby an extended period of infection, with an increased rate of evolution, creates viruses with substantial genetic novelty. However, measuring a rate of evolution during chronic infection is made more difficult by the potential existence of compartmentalisation in the viral population, whereby the viruses in a host form distinct subpopulations. We here describe and apply a novel statistical method to study within-host virus evolution, identifying the minimum number of subpopulations required to explain sequence data observed from cases of chronic infection, and inferring rates for within-host viral evolution. Across nine cases of chronic SARS-CoV-2 infection in hospitalised patients we find that non-trivial population structure is relatively common, with five cases showing evidence of more than one viral population evolving independently within the host. The detection of non-trivial population structure was more common in severely immunocompromised individuals (p = 0.04, Fisher's Exact Test). We find cases of within-host evolution proceeding significantly faster, and significantly slower, than that of the global SARS-CoV-2 population, and of cases in which viral subpopulations in the same host have statistically distinguishable rates of evolution. Non-trivial population structure was associated with high rates of within-host evolution that were systematically underestimated by a more standard inference method.
Humans↗
Comparative Genomics Reveals Convergent Evolution Between Avivorous Bats (Ia io and Nyctalus aviator).
Investigating the genetic basis of dietary specialization can provide insights into the evolution of niche breadth. In this study, we employed comparative genomics to investigate the adaptive mechanisms enabling two bat species (Nyctalus aviator and Ia io) to shift from insectivory to seasonal bird consumption (avivorous bats). Our findings revealed adaptation related to immune response and lipid metabolism in avivorous bat species. Avivorous bats exhibit strong positive selection and convergent evolution in immune-related genes, which are under heightened selective pressure compared to those of non-avivorous bats. These species also display significantly fewer endogenous retroviral elements. These findings emphasized the significance of immune-driven adaptive evolution in avivory. Additionally, our results showed that the dietary evolution of avivorous bats is accompanied by convergent evolution associated with the lipid metabolism. Notably, CEPT1, the upstream gene required for the activation of the PPAR pathway, underwent positive selection and convergence, which may have affected lipid metabolism. These adaptations may enable avivorous bat species to face the challenge of immune response and nutrition during dietary niche expansion. These findings not only provide comprehensive insights into the adaptive evolution driving the unique diet of avivorous bats but also offered novel perspectives on the molecular mechanisms underlying ecological niche evolution in a dietary context.
Animals↗
Clinical and cytogenetic significance of myelodysplastic syndromes with disease evolution.
We performed a retrospective study of 83 patients with myelodysplastic syndrome (MDS) to clarify the clinical and cytogenetic implications of disease evolution. Twenty-three patients showed disease progression; six of the 11 patients whose disease evolved within 100 days showed complex cytogenetic aberrations and most of them died within 300 days. Of the patients who survived more than 300 days, those with high bone marrow (BM) blast percentages experienced significant disease progression, but we noted no cytogenetic indicators for disease evolution at the later phase. Sixty percent of patients showing karyotypic evolution without disease evolution had deletion-type chromosome changes. The most frequent anomaly in patients with disease evolution who survived more than 300 days was an additional numerical change, whereas patients with disease evolution who survived less than 300 days showed karyotypic instability. It was difficult to predict disease progression for patients whose disease evolved more than 300 days after diagnosis, but in some patients the presence of additional numerical changes was related to disease progression. The cutoff level of early disease evolution was 100 days after diagnosis, and most patients with complex abnormalities survived less than 300 days with or without disease evolution.
Adult↗
Long-term evolution of gut inflammation in patients with spondyloarthropathy.
BACKGROUND & AIMS: Intestinal inflammation has been observed in patients with spondyloarthropathy (SpA). This prospective study reports the evolution of the intestinal inflammation observed in patients with SpA. METHODS: One hundred twenty-three patients with SpA who had undergone initial endoscopy were clinically reassessed. Intestinal evolution was evaluated by ileocolonoscopy and the histological study of biopsy specimens in 49 patients. RESULTS: Articular remission rates were independent of initial gut inflammation and associated with endoscopic and histological remission. Persistent gut inflammation was observed in active joint disease. Gut inflammation rarely disappeared, despite the persistence of articular complaints. Initial chronic gut inflammation implied a high risk of evolution to ankylosing spondylitis. Evolution to inflammatory bowel disease (IBD) was observed in 7% of patients. Mainly patients with initial chronic inflammation and mild complaints of diarrhea were at risk. Sulfasalazine was more frequently needed in the treatment of patients with gut inflammation with a beneficial effect on articular and intestinal evolution but did not prevent evolution to IBD. CONCLUSIONS: This study supports the etiopathogenetic role of the gut in SpA. Presence of chronic gut inflammation and mild complaints of diarrhea implies a high risk of evolution to ankylosing spondylitis and IBD. Sulfasalazine has a beneficial effect on articular activity by controlling gut inflammation, but it cannot prevent evolution to overt IBD.
Adolescent↗