Functional diversity (FD) has the potential to address many ecological questions, from impacts of global change on biodiversity to ecological restoration. There are several methods estimating the different components of FD. However, most of these methods can only be computed at limited spatial scales and cannot account for intraspecific trait variability (ITV), despite its significant contribution to FD. Trait probability density (TPD) functions (which explicitly account for ITV) reflect the probabilistic nature of niches. By doing so, the TPD approach reconciles existing methods for estimating FD within a unifying framework, allowing FD to be partitioned seamlessly across multiple scales (from individuals to species, and from local to global scales), and accounting for ITV. We present methods to estimate TPD functions at different spatial scales and probabilistic implementations of several FD concepts, including the primary components of FD (functional richness, evenness, and divergence), functional redundancy, functional rarity, and solutions to decompose beta FD into nested and unique components. The TPD framework has the potential to unify and expand analyses of functional ecology across scales, capturing the probabilistic and multidimensional nature of FD. The R package TPD (https://CRAN.R-project.org/package=TPD) will allow users to achieve more comparative results across regions and case studies.

• MeSH
• Biodiversity * MeSH
• Ecology * MeSH
• Phenotype MeSH
• Likelihood Functions MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Root-hemiparasitic plants of the genus Rhinanthus acquire resources through a water-wasting physiological strategy based on high transpiration rate mediated by the accumulation of osmotically active compounds and constantly open stomata. Interestingly, they were also documented to withstand moderate water stress which agrees with their common occurrence in rather dry habitats. Here, we focused on the water-stress physiology of Rhinanthus alectorolophus by examining gas exchange, water relations, stomatal density, and biomass production and its stable isotope composition in adult plants grown on wheat under contrasting (optimal and drought-inducing) water treatments. We also tested the effect of water stress on the survival of Rhinanthus seedlings, which were watered either once (after wheat sowing), twice (after wheat sowing and the hemiparasite planting) or continuously (twice and every sixth day after that). Water shortage significantly reduced seedling survival as well as the biomass production and gas exchange of adult hemiparasites. In spite of that drought-stressed and even wilted plants from both treatments still considerably photosynthesized and transpired. Strikingly, low-irrigated plants exhibited significantly elevated photosynthetic rate compared with high-irrigated plants of the same water status. This might relate to biochemical adjustments of these plants enhancing the resource uptake from the host. Moreover, low-irrigated plants did not acclimatize to water stress by lowering their osmotic potential, perhaps due to the capability to tolerate drought without such an adjustment, as their osmotic potential at full turgor was already low. Contrary to results of previous studies, hemiparasites seem to close their stomata in response to severe drought stress and this happens probably passively after turgor is lost in guard cells. The physiological traits of hemiparasites, namely the low osmotic potential associated with their parasitic lifestyle and the ability to withstand drought and recover from the wilting likely enable them to grow in dry habitats. However, the absence of osmotic adjustment of adults and sensitivity of seedlings to severe drought stress demonstrated here may result in a substantial decline of the hemiparasitic species with ongoing climate change.

• MeSH
• Biomass MeSH
• Dehydration MeSH
• Photosynthesis MeSH
• Stress, Physiological physiology   MeSH
• Plant Roots MeSH
• Plant Leaves anatomy & histology   physiology   MeSH
• Orobanchaceae anatomy & histology   physiology   MeSH
• Plant Stomata anatomy & histology   physiology   MeSH
• Seedlings anatomy & histology   physiology   MeSH
• Plant Transpiration MeSH
• Water * metabolism   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

BACKGROUND: Parasite evolution is hypothesized to select for levels of parasite virulence that maximise transmission success. When host population densities fluctuate, low levels of virulence with limited impact on the host are expected, as this should increase the likelihood of surviving periods of low host density. We examined the effects of Morogoro arenavirus on the survival and recapture probability of multimammate mice (Mastomys natalensis) using a seven-year capture-mark-recapture time series. Mastomys natalensis is the natural host of Morogoro virus and is known for its strong seasonal density fluctuations. RESULTS: Antibody presence was negatively correlated with survival probability (effect size: 5-8% per month depending on season) but positively with recapture probability (effect size: 8%). CONCLUSIONS: The small negative correlation between host survival probability and antibody presence suggests that either the virus has a negative effect on host condition, or that hosts with lower survival probability are more likely to obtain Morogoro virus infection, for example due to particular behavioural or immunological traits. The latter hypothesis is supported by the positive correlation between antibody status and recapture probability which suggests that risky behaviour might increase the probability of becoming infected.

• MeSH
• Survival Analysis MeSH
• Arenavirus immunology   isolation & purification   MeSH
• Behavior, Animal MeSH
• Arenaviridae Infections mortality   veterinary   MeSH
• Murinae * MeSH
• Rodent Diseases mortality   virology   MeSH
• Antibodies, Viral blood   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

BACKGROUND AND AIMS: Orchids are known to be particularly sensitive to environmental changes due to their narrow ranges of secondary successional habitats. Lack of data at the community level limits our ability to evaluate how traits of different species influence their responses to habitat change. Here, we used a diachronic survey of Mediterranean orchid communities in Corsica to examine this question. METHODS: Using data from two field surveys conducted 27 years apart (1982-84 and 2009-11) at the same 45 sites in Corsica, we evaluated the impact of increase in woody plant cover (WPC) on (i) the richness and composition and (ii) the local extinction/colonization dynamics of orchids. We applied a Bayesian multispecies site-occupancy model to each of the 36 orchid species recorded at these sites to estimate the detection probability of each species, enabling us to account for under-detection in estimating their dynamics. KEY RESULTS: Between 1982 and 2011, WPC changed at 82·3 % of sites (increasing at 75·6 %, decreasing at 6·7 %). Despite marked changes in composition of orchid communities at the local scale, no significant change was detected in species richness at the regional scale. Canopy closure affected the probability of new colonization of sites, but had no significant influence on the probability of local extinction. However, the abundance of shade-intolerant species declined more sharply than that of shade-requiring species. Among orchid species, the detection probability was significantly and positively correlated with population density and plant height. CONCLUSIONS: This study reveals contrasted dynamics of orchid communities between local and regional scales in Corsica. Although high turnover in communities was found at the local scale, regional species richness was maintained despite major land-use changes. Conserving landscape mosaics could provide locally suitable habitats for orchids of different ecologies to maintain diversity at larger spatial scales.

• MeSH
• Biodiversity MeSH
• Ecosystem * MeSH
• Orchidaceae physiology   MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• France MeSH

Few data are available about the regional or local extinction of tropical butterfly species. When confirmed, local extinction was often due to the loss of host-plant species. We used published lists and recent monitoring programs to evaluate changes in butterfly composition on Barro Colorado Island (BCI, Panama) between an old (1923-1943) and a recent (1993-2013) period. Although 601 butterfly species have been recorded from BCI during the 1923-2013 period, we estimate that 390 species are currently breeding on the island, including 34 cryptic species, currently only known by their DNA Barcode Index Number. Twenty-three butterfly species that were considered abundant during the old period could not be collected during the recent period, despite a much higher sampling effort in recent times. We consider these species locally extinct from BCI and they conservatively represent 6% of the estimated local pool of resident species. Extinct species represent distant phylogenetic branches and several families. The butterfly traits most likely to influence the probability of extinction were host growth form, wing size and host specificity, independently of the phylogenetic relationships among butterfly species. On BCI, most likely candidates for extinction were small hesperiids feeding on herbs (35% of extinct species). However, contrary to our working hypothesis, extinction of these species on BCI cannot be attributed to loss of host plants. In most cases these host plants remain extant, but they probably subsist at lower or more fragmented densities. Coupled with low dispersal power, this reduced availability of host plants has probably caused the local extinction of some butterfly species. Many more bird than butterfly species have been lost from BCI recently, confirming that small preserves may be far more effective at conserving invertebrates than vertebrates and, therefore, should not necessarily be neglected from a conservation viewpoint.

• MeSH
• Ecosystem MeSH
• Extinction, Biological * MeSH
• Phylogeny * MeSH
• Butterflies genetics   physiology   MeSH
• Islands MeSH
• DNA Barcoding, Taxonomic * MeSH
• Tropical Climate MeSH
• Animals MeSH
• Check Tag
• Animals 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
• Geographicals
• Islands MeSH
• Panama MeSH

1. Changes in embryonic development and growth were analysed in relation to direct changes in postnatal growth and correlated responses in egg parameters using Japanese quail lines selected for more than 30 generations for high (HG) and low (LG) relative gain of body weight (BW) between 11 and 28 d of age, and constant BW at 49 d of age. 2. During the first 42 h as well as at the end of incubation, LG embryos were developmentally accelerated in comparison with their HG counterparts. An expected increase of line divergence across generations was observed only in traits analysed at the end of incubation. 3. In contrast to early generations, LG embryos continuously exhibited a higher BW than HG embryos and this difference temporarily disappeared only around incubation d 8. Analogous to early generations, the HG compared with LG embryos showed two periods of transient growth retardation compensated subsequently by a higher growth rate (incubation d 3-8 and 8-16). 4. More pronounced growth retardation of HG versus LG embryos in late versus early generations corresponded to more distinct decrease of HG versus LG growth rate during the first post-hatch days. Likewise, a disappearance of line BW differences on incubation d 8 characterising the late generations corresponded to the elimination of line differences in adult BW. 5. Alterations of growth pattern were associated with changes of egg size. While HG quail maintained a relatively constant adult BW and egg size across generations, the gradually increasing incidence of large eggs in the LG line allowed selection of birds with higher growth potential, which in turn amplified the line differences in the embryonic BW and eliminated the line differences in adult BW. Line differences in egg composition (larger albumen with lower density in LG compared with HG eggs) apparently contributed to the strengthening of line developmental divergence during incubation. 6. Transient lack of nutrient supply to HG embryos due to their developmental delay is probably responsible for a higher HG versus LG embryo mortality.

• MeSH
• Time Factors MeSH
• Coturnix embryology   genetics   growth & development   MeSH
• Embryonic Development genetics   MeSH
• Selection, Genetic * MeSH
• Body Weight genetics   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH

BACKGROUND: About 30% of people on Earth have latent toxoplasmosis. Infected subjects do not express any clinical symptoms, however, they carry dormant stages of parasite Toxoplasma for the rest of their life. This form of toxoplasmosis is mostly considered harmless, however, recent studies showed its specific effects on physiology, behaviour and its associations with various diseases, including psychiatric disorders such as schizophrenia. Individuals who suffer from schizophrenia have about 2.7 times higher prevalence of Toxoplasma-seropositivity than controls, which suggests that some traits characteristic of schizophrenic patients, including the sex difference in schizophrenia onset, decrease of grey matter density in specific brain areas and modification of prepulse inhibition of startle reaction could in fact be caused by toxoplasmosis for those patients who are Toxoplasma-seropositive. METHODOLOGY/PRINCIPAL FINDINGS: We measured the effect of prepulse inhibition/facilitation of the startle reaction on reaction times. The students, 170 women and 66 men, were asked to react as quickly as possible to a startling acoustic signal by pressing a computer mouse button. Some of the startling signals were without the prepulse, some were 20 msec. preceded by a short (20 msec.) prepulse signal of lower intensity. Toxoplasma-seropositive subjects had longer reaction times than the controls. Acoustic prepulse shorted the reaction times in all subjects. This effect of prepulse on reaction times was stronger in male subjects and increased with the duration of infection, suggesting that it represented a cumulative effect of latent toxoplasmosis, rather than a fading out after effect of past acute toxoplasmosis. CONCLUSIONS: Different sensitivity of Toxoplasma-seropositive and Toxoplasma-seronegative subjects on effect of prepulses on reaction times (the toxoplasmosis-prepulse interaction) suggested, but of course did not prove, that the alternations of prepulse inhibition of startle reaction observed in schizophrenia patients probably joined the list of schizophrenia symptoms that are in fact caused by latent toxoplasmosis.

• MeSH
• Adult MeSH
• Humans MeSH
• Young Adult MeSH
• Reaction Time MeSH
• Schizophrenic Psychology MeSH
• Schizophrenia immunology   parasitology   physiopathology   MeSH
• Sex Factors MeSH
• Toxoplasma physiology   MeSH
• Toxoplasmosis immunology   parasitology   physiopathology   psychology   MeSH
• Reflex, Startle physiology   MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Cíl studie: Na základě soudobých studií podat přehled o hlavních biologických funkcích lipoproteinů o vysoké hustotě (HDL), zejména ve vztahu k reverznímu transportu cholesterolu a k jejich protizánětlivému působení. Popsat pravděpodobné mechanismy vzniku dysfunkčních prozánětlivých HDL a uvést některé parametry asociované s tímto procesem. Podat přehled o laboratorních metodách stanovení kvantitativních, strukturních a funkčních vlastností HDL, včetně moderních metod založených na hmotové spektrometrii. Typ studie: přehledový článek Závěr: V případě systémového zánětu a/nebo oxidačního stresu dochází ke vzniku dysfunkčních HDL akumulujících oxidanty. Probíhá strukturní modifikace apolipoproteinu AI, což vede mimo jiné k inhibici reverzního transportu cholesterolu a tvorbě prozánětlivých HDL. Na ztrátě příznivých vlastností HDL se podílí modifikace proteinové i lipidové složky HDL. Izolované měření HDL cholesterolu nemusí u některých syndromů bezvýhradně korelovat s mírou kardiovaskulárního rizika a v některých situacích je vhodné stanovit markery mapující strukturu a funkci HDL.

Objective: On the basis of recent studies to make an overview concerning the crucial biological functions of high density lipoproteins (HDL), with emphasis on the role in reverse cholesterol transport and their antiinflammatory traits. The aim was to describe probable mechanisms of dysfunctional proinflammatory HDL formation with introduction some of associated parameters. To present laboratory methods for determination of quantitative, structural and functional qualities of HDL, including advanced mass spectrometry techniques. Study design: review Conclusion: In the case of systemic inflammation and/or oxidative stress, the formation of dysfunctional HDL accumulating oxidants takes place, including apo AI structural modifications. This process can lead to the inhibition of reverse cholesterol transport and proinflammatory HDL generation, among others. Loss of beneficial qualities results from modification of both lipid and protein components of HDL. In some cases, an isolated quantitative measurement of HDL cholesterol may not fully correlate with cardiovascular risk and it is eligible to determine some of structural and/or functional markers of HDL.

• MeSH
• Adiponectin analysis   therapeutic use   MeSH
• Apolipoproteins analysis   MeSH
• Aryldialkylphosphatase analysis   therapeutic use   MeSH
• Adult MeSH
• Cholesterol, HDL analysis   MeSH
• Mass Spectrometry MeSH
• Myocardial Ischemia diagnosis   prevention & control   MeSH
• Cardiovascular Diseases diagnosis   prevention & control   MeSH
• Clinical Laboratory Techniques methods   utilization   MeSH
• Humans MeSH
• Lipoproteins, HDL * physiology   classification   MeSH
• Peroxidase analysis   therapeutic use   MeSH
• Proteomics * MeSH
• Aged MeSH
• Cholesterol Ester Transfer Proteins MeSH
• Chromatography, High Pressure Liquid MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Research Support, Non-U.S. Gov't MeSH

The genes that cause or increase susceptibility to essential hypertension (EH) and related animal models remain unknown. Their identification is unlikely to be realized with current genetic approaches, because of ambiguities in the genotype-phenotype relationships in these polygenic disorders. In turn, the phenotype is not just an aggregate of traits, but needs to be related to specific components of the circulatory control system at different stages of EH. Hence, clues about important genes must come through the phenotype, reversing the order of current approaches. A recent systems analysis has highlighted major differences in circulatory control in the two main syndromes of EH: 1) stress-and-salt-related EH (SSR-EH) – a constrictor hypertension with low blood volume; 2) hypertensive obesity – SSR-EH plus obesity. Each is initiated through sensitization of central synapses linking the cerebral cortex to the hypothalamic defense area. Several mechanisms are probably involved, including cerebellar effects on baroreflexes. The result is a sustained increase in sympathetic neural activity at stimulus levels that have no effect in normal subjects. Subsequent progression of EH is largely through interactions with non-neural mechanisms, including changes in concentration of vascular autacoids (e.g. nitric oxide) and the amplifying effect of structural changes in large resistance vessels. The rising vasoconstriction increases heterogeneity of blood flow, causing rarefaction (decreased microvascular density) and deterioration of vital organs. SSR-EH also increases food intake in response to stress, but only 40% of these individuals develop hypertensive obesity. Their brain ignores the adiposity signals that normally reduce eating. Hyperinsulinemia masks the sympathetic vasoconstriction through its dilator action, raises blood volume, whilst renal nephropathy and other diabetic complications are common. In each syndrome the neural and non-neural determinants of hypertension provide targets for identifying high BP genes. Reading the genome from the phenotype will require new approaches, such as those used in developmental genetics. In addition, transgenic technology may help verify hypotheses and examine whether an observed effect is through single or multiple mechanisms. To obtain answers will require substantial collaborative efforts between physiologists and geneticists.

• MeSH
• Phenotype MeSH
• Hyperinsulinism complications   MeSH
• Hypertension epidemiology   genetics   MeSH
• Humans MeSH
• Obesity genetics   MeSH
• Vasoconstriction physiology   genetics   MeSH
• Check Tag
• Humans MeSH

• MeSH
• Behavior MeSH
• Molecular Biology MeSH
• Nervous System Diseases MeSH
• Nervous System MeSH
• Neurochemistry MeSH
• Neurophysiology MeSH
• Neurons MeSH
• Neurosciences MeSH
• Publication type
• Monograph MeSH

• Conspectus
• Fyziologie člověka a srovnávací fyziologie
• NML Fields
• neurovědy
• biologie