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The dominant rodent species in Central European agricultural landscapes are granivorous mouse species and herbivorous common voles. Although our knowledge of European wood mice is relatively good, there is a distinct lack of information on pygmy field mice inhabiting Central and Eastern Europe and Central Asia. In this study, we examine the food quality of pygmy field mice in relation to environmental and population factors, and compare the food quality of related mouse species and common voles living in the same study plots. The dietary quality of the pygmy field mouse is similar to that of other mouse species; however, the food quality of pygmy field mice and common voles differed substantially, with mice having lower and more variable nitrogen content. For both rodent species, factors such as body size, age and sex had no influence on diet quality. Pygmy field mouse diet was mainly dependent on season, while total abundance had greatest influence on common vole diet.
Microscopic inclusions have been observed in 7 out of 106 European eel (Anguilla anguilla L.) sagittae using polarizing microscope and scanning electron microscope meanwhile the annual increments were studied to characterize the age structure of the population living in Lake Balaton. The presence of vaterite, a rare calcium carbonate polymorph was observed in these inclusions using Raman spectroscopy. Vateritic sagittae in wild fish are usually considered as symptom of physiological stress. The observed fusiform inclusions represent a new morphological type of vaterite inclusions in eel otolith. Two alternatives are hypothesized to explain their formation: 1) metabolic disorder, such as erroneous protein synthesis; 2) introduction of an alien protein into the eel’s inner ear. The origin and physiological significance of this new morphological type of vateritic inclusions is still an open question. Same as whether it can be found in other species or specific only to eel otoliths.
The association between terrestrial plants and arbuscular mycorrhizal (AM) fungi is one of the most common and widespread mutualistic plant-fungi interaction. AM fungi are of beneficial effects on the water and nutrient uptake of plants and increase plant defense mechanisms to alleviate different stresses. The aim of this study was to determine the level of polyphenol oxidase (PPO), guaiacol peroxidase (POX) and glutathione S-transferase (GST) enzyme activities and to track the expression of glutathione S-transferase (GST) gene in plant-arbuscular mycorrhizal system under temperature- and mechanical stress conditions. Our results suggest that induced tolerance of mycorrhizal sunflower to high temperature may be attributed to the induction of GST, POX and PPO enzyme activities as well as to the elevated expression of GST. However, the degree of tolerance of the plant is significantly influenced by the age which is probably justified by the energy considerations.
A pot experiment was conducted to study the response of barley (Hordeum vulgare) to inoculation with Glomus fasciculatum in unsterilised organic matter amended soils on the colonization of barley roots by (V)-Arbuscular mycorrhizal (AM) fungi and other rhizosphere microflora. The populations of bacteria, fungi and actinomycetes were higher in amended than in control soils. Paddy straw compost (PSC) stimulated all three groups of organisms (bacteria, fungi and actinomycetes) more than city compost (CC). The fungal and actinomycetes populations decreased with increasing plant age. The effect was more pronounced in the rhizosphere of paddy straw-amended soils. The mycorrhizal spore count and the colonization of barley roots by (V)-AM were more pronounced in soils amended with PSC than in those amended with CC.
Concentration of carbon (C), oxygen (O), nitrogen (N), magnesium (Mg), aluminium (Al), silicon (Si), phosphorus (P), mercury (Hg), sulphur (S), lead (Pb), chlorine (Cl), potassium (K), cadmium (Cd), calcium (Ca), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), copper (Cu) and zinc (Zn), in the form of weight percentage, in the needles of different age classes, current and previous year one, of two sites, Risnjak National Park and Donja Dobra (control), were measured by X-ray microanalysis (EDAX) in the Scanning Electron Microscope in silver fir trees (Abies alba Mill.). The analysis suggests that accumulation of elements, in both years, particularly that of heavy metals, appeared in polluted site, like Risnjak, in the higher amount, whereas in non polluted, like Donja Dobra, in the lower amount. Moreover, it seems likely that elements at the first sites were accumulated and contaminated in very young current year needles, while in non polluted in somewhat older, the previous year ones.
The herbarium of Paulus Kitaibel (1757–1817) has been preserved in good condition and can still be used for the investigation of problematic questions. There happens to be a misidentified specimen on the back of one of the sheets. Although it has been studied by several botanists, it has proved impossible to identify this species because important morphological traits have been lost due to the age of the preserved material. The complete ITS region of the over 200-year-old herbarium specimen has been amplified by PCR. Sequence analysis and the secondary structure modelling of the ITS2 RNA transcript clearly provided, that the specimen is Solanum scabrum , thus settling the controversy surrounding this question. This result is particularly interesting, as the presence of S. scabrum in the Hungarian flora, has never been officially documented.
Abstract
Mycobacterium tuberculosis, the causative agent of Tuberculosis has plagued humankind for ages and has surfaced stronger than ever with the advent of drug resistance. Mycobacteria are adept at evading the host immune system and establishing infection by engaging host factors and secreting several virulence factors. Hence these secretion systems play a key role in mycobacterial pathogenesis. The type VII secretion system or ESX (early secretory antigenic target (ESAT6) secretion) system is one such crucial system that comprises five different pathways having distinct roles in mycobacterial proliferation, pathogenesis, cytosolic escape within macrophages, regulation of macrophage apoptosis, metal ion homeostasis, etc. ESX 1–5 systems are implicated in the secretion of a plethora of proteins, of which only a few are functionally characterized. Here we summarize the current knowledge of ESX secretion systems of mycobacteria with a special focus on ESX-1 and ESX-5 systems that subvert macrophage defenses and help mycobacteria to establish their niche within the macrophage.
Changes in species composition during the succession of ecological communities potentially reflect the differential effects of environmental filters and limiting similarity on structuring communities. As ecological succession can represent community assembly in action, understanding how successional time affects the functional and phylogenetic structure of communities can reveal the influence of different factors on the assembly process. We analysed functional patterns of multiple traits related to the succession of tropical forests to answer if there are trait convergence and/or divergence with regeneration age, and if functional and phylogenetic diversity can be predicted by forest age. We compiled checklists from studies of 23 successional forests in Brazilian Atlantic Forest, ranging from 4 to 120 years old. We also compiled functional traits for a total of 355 species. We analysed the data by a method that includes scaling-up trait-based data to the community level and matrix correlations of multiple traits. We built linear models to show the relationship between each trait and diversity (taxonomic, functional and phylogenetic) with successional time. We found no phylogenetic signal at the species pool and metacommunity levels, but significant trait divergence (tree guild, leaf slenderness, leaf area, pollination entomophilous generalist and pollination by vertebrate) and trait convergence (arboreal habitus, tree guild, leaf compoundness, pollination entomophilous generalist) patterns related to the successional gradient. Also, functional diversity increased during succession, with a significant increase in leaf slenderness and zoochoric dispersal and decrease in tree guild. Phylogenetic diversity also increased along the successional gradient. We found that the communities in the studied successional gradient are structured by both environmental (measured by trait convergence) and biotic (measured by trait divergence) filtering. The species turnover and diversification at taxonomic level are followed by well-defined patterns of trait turnover, revealing that community assembly is constrained by environmental filters at the beginning and by limiting similarity at the advanced stages of the succession.
Matkovic, V., Ilich, J. Z., Skugor, M., Badenhop, N. E., Goel, P., Clairmont, A., Klisovic, D., Nahhas, R. W., Landoll, J. D. (1997) Leptin is inversely related to age at menarche in human females. J. Clin. Endocrinol. Metab. 82 , 3239
841 846 Pang, S. F., Tsang, C. W., Hong, G. X., Vip, P. C., Tang, P. L., Brown, G. M. (1990) Fluctuation of blood melatonin concentrations with age: result of changes in pineal
