Impressive advances in molecular genetic techniques allow to analyze the effects of natural selection on the development of human genome. For example, the trend towards blonde hair and blue eyes was documented. The approach to analyze possible effects of natural selection on the evolution of recent phenotypes with high risk of cardiovascular disease has not been described yet. A possible effect on the evolution of two main risk factors - hypercholesterolemia and hypertension - is presented. The close relationship of non-HDL cholesterol blood concentration to the proportion of pro-inflammatory macrophages in human visceral adipose tissue might be a result of long-lasting natural selection. Individuals with higher proportion of this phenotype might also display a higher ability to fight infection, which was very common in human setting from prehistory until Middle Ages. Successful battle against infections increased the probability to survive till reproductive age. Similar hypothesis was proposed to explain frequent hypertension in African Americans. A long-lasting selection for higher ability to conserve sodium during long-term adaptation to low sodium intake and hot weather was followed by a short-term (but very hard) natural selection of individuals during transatlantic slave transport. Only those with very high capability to retain sodium were able to survive. Natural selection of phenotypes with high plasma cholesterol concentration and/or high blood pressure is recently potentiated by high-fat high-sodium diet and overnutrition. This hypothesis is also supported by the advantage of familial hypercholesterolemia in the 19th century (at the time of high infection disease mortality) in contrast to the disadvantage of familial hypercholesterolemia during the actual period of high cardiovascular disease mortality.

• MeSH
• Genome, Human genetics   MeSH
• Cardiovascular Diseases epidemiology   genetics   MeSH
• Humans MeSH
• Evolution, Molecular * MeSH
• Risk MeSH
• Selection, Genetic genetics   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH

• MeSH
• Biological Evolution MeSH
• Threshold Limit Values MeSH
• Environmental Pollution MeSH

Most studies of bacterial pathogen populations have been based on isolates collected from individuals with disease, or their contacts, over short time periods. For commensal organisms that occasionally cause disease, such as Neisseria meningitidis, however, the analysis of isolates from long-term asymptomatic carriage is necessary to elucidate their evolution and population structure. Here, we use mathematical models to analyse the structuring and dynamics of three vaccine-candidate antigens among carried meningococcal isolates collected over nearly 30 years in the Czech Republic. The data indicate that stable combinations of antigenic alleles were maintained over this time period despite evidence for high rates of recombination, consistent with theoretical models in which strong immune selection can maintain non-overlapping combinations of antigenic determinants in the presence of recombination. We contrast this antigenic structure with the overlapping but relatively stable combinations of the housekeeping genes observed among the same isolates, and use a novel network approach to visualize these relationships.

• MeSH
• Alleles MeSH
• Antigens, Bacterial genetics   immunology   MeSH
• Bacterial Proteins genetics   MeSH
• Models, Biological MeSH
• Genetic Variation MeSH
• Humans MeSH
• Meningitis, Meningococcal microbiology   MeSH
• Evolution, Molecular * MeSH
• Neisseria meningitidis genetics   immunology   MeSH
• Porins genetics   immunology   MeSH
• Carrier State microbiology   MeSH
• Bacterial Outer Membrane Proteins genetics   immunology   MeSH
• Recombination, Genetic MeSH
• Selection, Genetic MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic MeSH

Due to the lack of fossil evidence, the timescales of bacterial evolution are largely unknown. The speed with which genetic change accumulates in populations of pathogenic bacteria, however, is a key parameter that is crucial for understanding the emergence of traits such as increased virulence or antibiotic resistance, together with the forces driving pathogen spread. Methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of hospital-acquired infections. We have investigated an MRSA strain (ST225) that is highly prevalent in hospitals in Central Europe. By using mutation discovery at 269 genetic loci (118,804 basepairs) within an international isolate collection, we ascertained extremely low diversity among European ST225 isolates, indicating that a recent population bottleneck had preceded the expansion of this clone. In contrast, US isolates were more divergent, suggesting they represent the ancestral population. While diversity was low, however, our results demonstrate that the short-term evolutionary rate in this natural population of MRSA resulted in the accumulation of measurable DNA sequence variation within two decades, which we could exploit to reconstruct its recent demographic history and the spatiotemporal dynamics of spread. By applying Bayesian coalescent methods on DNA sequences serially sampled through time, we estimated that ST225 had diverged since approximately 1990 (1987 to 1994), and that expansion of the European clade began in 1995 (1991 to 1999), several years before the new clone was recognized. Demographic analysis based on DNA sequence variation indicated a sharp increase of bacterial population size from 2001 to 2004, which is concordant with the reported prevalence of this strain in several European countries. A detailed ancestry-based reconstruction of the spatiotemporal dispersal dynamics suggested a pattern of frequent transmission of the ST225 clone among hospitals within Central Europe. In addition, comparative genomics indicated complex bacteriophage dynamics.

• MeSH
• Biological Evolution * MeSH
• Time MeSH
• DNA, Bacterial MeSH
• Methicillin-Resistant Staphylococcus aureus * genetics   MeSH
• Polymerase Chain Reaction MeSH
• Polymorphism, Genetic MeSH
• Population Dynamics MeSH
• Genetics, Population MeSH
• Staphylococcal Infections epidemiology   MeSH
• Chromatography, High Pressure Liquid MeSH
• Publication type
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Europe MeSH

Diatoms outcompete other phytoplankton for nitrate, yet little is known about the mechanisms underpinning this ability. Genomes and genome-enabled studies have shown that diatoms possess unique features of nitrogen metabolism however, the implications for nutrient utilization and growth are poorly understood. Using a combination of transcriptomics, proteomics, metabolomics, fluxomics, and flux balance analysis to examine short-term shifts in nitrogen utilization in the model pennate diatom in Phaeodactylum tricornutum, we obtained a systems-level understanding of assimilation and intracellular distribution of nitrogen. Chloroplasts and mitochondria are energetically integrated at the critical intersection of carbon and nitrogen metabolism in diatoms. Pathways involved in this integration are organelle-localized GS-GOGAT cycles, aspartate and alanine systems for amino moiety exchange, and a split-organelle arginine biosynthesis pathway that clarifies the role of the diatom urea cycle. This unique configuration allows diatoms to efficiently adjust to changing nitrogen status, conferring an ecological advantage over other phytoplankton taxa.

• MeSH
• Models, Biological MeSH
• Chloroplasts genetics   metabolism   MeSH
• Nitrates metabolism   MeSH
• Nitrogen metabolism   MeSH
• Metabolic Networks and Pathways genetics   MeSH
• Metabolomics methods   MeSH
• Mitochondria genetics   metabolism   MeSH
• Evolution, Molecular MeSH
• Seawater microbiology   MeSH
• Proteomics methods   MeSH
• Gene Expression Regulation MeSH
• Diatoms genetics   metabolism   MeSH
• Signal Transduction genetics   MeSH
• Gene Expression Profiling methods   MeSH
• Carbon metabolism   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

• MeSH
• Philosophy MeSH
• Linguistics MeSH

• Conspectus
• Věda. Všeobecnosti. Základy vědy a kultury. Vědecká práce
• NML Fields
• humanitní vědy a umění

BACKGROUND: Female promiscuity is highly variable among birds, and particularly among songbirds. Comparative work has identified several patterns of covariation with social, sexual, ecological and life history traits. However, it is unclear whether these patterns reflect causes or consequences of female promiscuity, or if they are byproducts of some unknown evolutionary drivers. Moreover, factors that explain promiscuity at the deep nodes in the phylogenetic tree may be different from those important at the tips, i.e. among closely related species. Here we examine the relationships between female promiscuity and a broad set of predictor variables in a comprehensive data set (N = 202 species) of Passerides songbirds, which is a highly diversified infraorder of the Passeriformes exhibiting significant variation in female promiscuity. RESULTS: Female promiscuity was highly variable in all major clades of the Passerides phylogeny and also among closely related species. We found several significant associations with female promiscuity, albeit with fairly small effect sizes (all R2 ≤ 0.08). More promiscuous species had: 1) less male parental care, particularly during the early stages of the nesting cycle (nest building and incubation), 2) more short-term pair bonds, 3) greater degree of sexual dichromatism, primarily because females were drabber, 4) more migratory behaviour, and 5) stronger pre-mating sexual selection. In a multivariate model, however, the effect of sexual selection disappeared, while the other four variables showed additive effects and together explained about 16% of the total variance in female promiscuity. Female promiscuity showed no relationship with body size, life history variation, latitude or cooperative breeding. CONCLUSIONS: We found that multiple traits were associated with female promiscuity, but these associations were generally weak. Some traits, such as reduced parental care in males and more cryptic plumage in females, might even be responses to, rather than causes of, variation in female promiscuity. Hence, the high variation in female promiscuity among Passerides species remains enigmatic. Female promiscuity seems to be a rapidly evolving trait that often diverges between species with similar ecologies and breeding systems. A future challenge is therefore to understand what drives within-lineage variation in female promiscuity over microevolutionary time scales.

• MeSH
• Biological Evolution * MeSH
• Breeding MeSH
• Ecology MeSH
• Phylogeny MeSH
• Pair Bond MeSH
• Sexual Behavior, Animal * MeSH
• Body Size MeSH
• Songbirds genetics   physiology   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

After having shortly presented Abbott, a genious, the first one who could cure scoliosis, and briefly described the main principles of bracing and the way the other schools are bracing now, the authors present the model that one of them has conceived. It is build with polyethylene. Fifty four zones are taken in account on the scoliosis body.Wide and deep spaces must be managed on concave areas. It has to be adjusted to patient,immediately after delivery, regularly during the duration of a brace and occasionally if necessary. The height, width and breadth as well as many details can be adjusted at least as well as in all other methods. Nine kinds of mechanisms, 4 active and 5 passive, contribute altogether to the correction of scoliosis. A series of short term results is presented, where angle according to Cobb, rotation, rib static and wedge shape are evaluated. All those features had got an average bettering of 41 to 60 %.

• MeSH
• Humans MeSH
• Orthopedic Fixation Devices history   classification   utilization   MeSH
• Orthotic Devices classification   utilization   MeSH
• Scoliosis history   physiopathology   therapy   MeSH
• Outcome and Process Assessment, Health Care methods   utilization   MeSH
• Braces history   classification   utilization   MeSH
• Spinal Curvatures complications   physiopathology   therapy   MeSH
• Ribs physiopathology   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Review MeSH

• MeSH
• Clinical Medicine MeSH
• Contact Lenses MeSH
• Curriculum MeSH
• Ophthalmology MeSH
• Optics and Photonics MeSH
• Refraction, Ocular MeSH
• Science MeSH

• Conspectus
• Ortopedie. Chirurgie. Oftalmologie
• Učební osnovy. Vyučovací předměty. Učebnice
• NML Fields
• věda a výzkum
• oftalmologie
• NML Publication type
• učebnice vysokých škol

Aims: To investigate the associations of physical-activity trajectories with the level of cognitive performance and its decline in adults 50 years of age or older. Methods: We studied 38729 individuals (63 ± 9 years; 57% women) enrolled in the Survey of Health, Ageing and Retirement in Europe (SHARE). Physical activity was self-reported and cognitive performance was assessed based on immediate recall, verbal fluency, and delayed recall. Physical-activity trajectories were estimated using growth mixture modelling and linear mixed effects models were used to investigate the associations between the trajectories and cognitive performance. Results: The models identified two physical-activity trajectories of physical activity: constantly-high physical activity (N=27634: 71%) and decreasing physical activity (N=11095; 29%). Results showed that participants in the decreasing physical-activity group exhibited a lower level of cognitive performance compared to the high physical-activity group (immediate recall: ß=0.94; 95% confidence interval [CI]=0.92 to 0.95; verbal fluency: ß=0.98; 95% CI=0.97 to 0.98; delayed recall: ß=0.95; 95% CI=0.94 to 0.97). Moreover, compared with participants in the constantly-high physical-activity group, participants in the decreasing physical-activity group showed a steeper decline in all cognitive measures (immediate recall: ß=-0.04; 95% CI=-0.05 to -0.04; verbal fluency: ß=-0.22; 95% CI=-0.24 to -0.21; delayed recall: ß=-0.04; 95% CI=-0.05 to -0.04). Conclusions: Physical-activity trajectories are associated with the level and evolution of cognitive performance in adults over 50 years. Specifically, our findings suggest that a decline in physical activity over multiple years is associated with a lower level and a steeper decline in cognitive performance.

• MeSH
• Exercise MeSH
• Cognition MeSH
• Cognitive Dysfunction * epidemiology   MeSH
• Memory, Short-Term MeSH
• Humans MeSH
• Aging MeSH
• Health Surveys MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH