卷 71, 编号 4 (2016)

Phenotypic plasticity, i.e., the ability of a genotype to produce various phenotypes in response to changes in the environment, plays an important, although poorly understood and often underestimated, role in evolution. Both adaptive and nonadaptive phenotypic plasticity modulate the strength and direction of selection acting on a population and can, depending on conditions, either accelerate or inhibit adaptation, divergence, and speciation. Phenotypic plasticity also affects the direction of evolutionary change, which can either coincide with the direction of plastic changes (genetic assimilation) or be the opposite (genetic compensation). A special case of phenotypic plasticity is phenotypic change of the host caused by changes in its symbiotic microbiota. In the current review, we discuss the main forms of phenotypic plasticity and the current data on their impact on the rate and direction of evolutionary change. Special attention is paid to the results of recent experimental work, including the long-term evolutionary experiment on Drosophila melanogaster, which is being held at the Department of Evolutionary Biology, School of Biology, Moscow State University.

The article provides information on the mean age of death (MAD) for 54 256 men professionally involved in research work and assigned to one of the six categories, namely, physics, chemistry, medicine and biology, mathematics, economics, and humanities. In addition, the effect of teaching activity on MAD and longevity has been evaluated for scientists of different specialties. Special attention has been paid to the analysis of MAD of the deceased members of the Russian Academy of Sciences, including members of the USSR Academy of Sciences (1724–2013). The minimum MAD has been found for mathematicians (72.1 ± 0.21 years) and the maximum MAD for scientists in economics (74.6 ± 0.26 years). The relative number of surviving ≥90 years and ≥100 years is minimal for mathematicians (7.59 and 0.37%, respectively), whereas those numbers for economists reveal the maximum values (10.26 and 0.96%, respectively). Indicators of MAD and proportion of centenarians among the scientists who received public recognition strongly depend on the specialty. Similarly, the members of the Russian Academy of Sciences and the USSR Academy of Sciences have the highest MAD in economics (74.7 ± 1.05 years) and the lowest in mathematics (70.6 ± 0.74 years). MAD has proven to be 3.5 years higher for scientists involved in teaching at university or college compared to those who were not involved in teaching. In this case, the “gain” is significant, ranging from 3.1 years for economists and humanitarians to 4.9 years for mathematicians. The results of the study lead to the conclusion that intense scientific work contributes to an increase in life expectancy and longevity.

In the review, the main types of autophagy (macroautophagy, microautophagy, and chaperonemediated autophagy) are shortly described. Data about the character of the influence of autophagy on the aging process and on the development of some neurodegenerative diseases in various organisms are analyzed. It is noted that this effect is usually (though not always) beneficial. Results of investigations of the phenomenon in experiments on mice, nematodes, fruit flies, bacteria, yeast, and cell cultures of higher organisms are considered. Obvious relationship between autophagy activation and cell proliferation restriction is emphasized. The latter, in our opinion, is the main cause of age-related accumulation of various defects (the most important of them is DNA damage) in cells and tissues, which leads to an increase in the death probability (i.e., to aging). It is concluded that studies of the role of autophagy in the aging process on the models of chronological aging in yeast or stationary phase aging of cell cultures could be considered as the most appropriate approach to the problem solution.

We have developed microcarriers made from silk fibroin. Microcarriers can be used as a substrate for cell cultivation and cell delivery during cell-based therapy and for the construction of bioengineered tissue. Fibroin microcarriers were mineralized, which led to the appearance of calcium phosphate crystals on their surface. The ability of mineralized and nonmineralized microcarriers to support osteogenic differentiation of the osteoblast-like cell line MG-63 was estimated by alkaline phosphatase activity, an early marker of bone formation. The experiment showed cells actively proliferating on the surface of both mineralized and nonmodified microcarriers. Culturing MG-63 on the surface of fibroin microcarriers resulted in an increase of alkaline phosphatase activity indicative of osteogenic differentiation of MG-63 cells in the absence of inductors. The level of alkaline phosphatase was higher when mineralized microcarriers were used. Alkaline phosphatase activity of MG-63 cells cultivated using traditional two-dimensional approaches were close to zero. As opposed to conventional monolayer culturing, microcarrier culture cells are in a three-dimensional environment that is closer to physiological conditions. This can have a significant impact on their morphology and functional properties. During this study, we also characterized mechanical properties of porous scaffolds used for microcarriers.

In the marine mycobiota of decaying plant materials near Pertsov White Sea Biological Station, numerous fungi were found, two of them are new to the White Sea. Residues of littoral halophytes were collected in August 2009 and 2015 in the supralittoral area; the work was carried out by noncultural methods. New to the White Sea species Phaeosphaeria neomaritima (R.V. Gessner et Kohlm.) Shoemaker et C.E. Babc. were found on 11 fragments, mostly on the residues of halophyte plants Juncus atrofuscus (rush). P. neomaritima is detected in both years in different points of the investigated area. Ascocarps of this fungus were immature. Apparently, they mature later than mid-August in the White Sea. The second species, Pleospora triglochinicola Webster, is new not only for White Sea but also for all Russian Seas. It is found in the 12 fragments of halophyte Triglochin maritima, in both years, on different points of investigated area. Both species are common in the study area. The article contains descriptions and photographs, as well as discussions on the environmental and geographical distribution of these species.

Characteristics of four natural water samples from urban and rural areas and the efficiency of a new purifying agent, potassium ferrate K₂FeO₄, were studied by bacterial luminescence bioassay for 30 minutes. It was revealed that two samples of water from the urban areas are toxic, while the other two samples (one from urban and one from rural environment) are nontoxic. Numerous data obtained on the increase in toxicity index with time allow reasonable conclusions to be made about the chemical nature of substances present in the test water samples. Toxic natural water samples were likely to contain heavy metals and were well purified using potassium ferrate, including via their adsorption. In nontoxic natural water samples, toxic complexes with organic compounds present in water could form at the addition of potassium ferrate. The obtained data call for further studying the properties of potassium ferrate complexes with organic compounds. Bacterial luminescence bioassay is a promising method for the rapid assessment of properties of various water sources (their integral toxicity and presumable chemical composition) and new reagents for their purification (effective concentrations, bactericidal properties, and mechanisms of interacting with heavy metals and organic substances in water).

Amplification of sea buckthorn Hippophae rhamnoides L. 5S rDNA nontranscribed spacer with coding border anneal primers showed existence of a single fragment. The fragment was cloned and sequenced. It was shown that length of the Hippophae rhamnoides L. 5S rDNA nontranscribed spacer is 807 bp. Analysis of the sequence allowed to detect a high homology with early described microsatellite locuses of Hippophae rhamnoides L., russian olive Elaeagnus angustifolia L., and Calligonum mongolicum Turcz. that include a (GA)₉ motif. These results may be useful to study a ribosomal RNA gene organization.

Protective effect of the natural dipeptide carnosine on the antioxidant system of rats under conditions of oxidative stress caused by chronic cadmium administration was investigated. Oxidative status of experimental animals were evaluated based on a number of informative parameters of iron-induced chemiluminescence. It was shown that the introduction of cadmium for 7 days reduces the duration of the latent period of chemiluminescence in the brain, liver, and blood plasma suggesting the depletion of endogenous antioxidant defense. Coexposure to carnosine and cadmium led to significant increase in the level of antioxidant protection in plasma, liver, and brain of animals. Carnosine also prevented the increase of lipid hydroperoxides in the brain and prevented the development of lipid peroxidation content in liver and plasma of animals. Mechanism of the protective effect of carnosine under conditions of oxidative stress induced by cadmium administration was shown on human neuroblastoma SH-SY5Y cell culture. Addition of the cadmium to the incubation medium to a final concentration of 5 μM reduced cell viability of a culture, as was determined by MTT assay; simultaneous addition of carnosine (0.25 mM final concentration) with cadmium resulted in increased cell viability during 24 hours of incubation. Thus, carnosine in a final concentration of 1 mM effectively prevented the development of necrotic lesions of neuroblastoma cells, inhibiting the formation of reactive oxygen species as measured by flow cytometry. The results indicate the ability of carnosine to prevent the development of oxidative stress under the toxic action of cadmium.

The aim of this study was to investigate the relationship between individual electroencephalogram (EEG) characteristics in the resting state and the level of nonverbal intelligence. The study involved 77 students of Demidov Yaroslavl State University. Analysis of the relationship between IQ and spectral parameters of EEG theta, alpha, and two subbands of beta oscillations revealed that the amplitude and power of alphaband EEG oscillations and low frequency beta-band EEG oscillations were positively correlated with the performance in the nonverbal intelligence test. The variety of brain periodic regimes was assessed using the correlation dimension (CD) of EEG. The correlation dimension can be used to quantify the degree of complexity of the nonlinear dynamical system. It was found that the value of the EEG correlation dimension was positively associated with the level of intelligence. The periodicity of the EEG signal was studied using autocorrelation analysis. It was shown that the autocorrelogram duration was negatively associated with IQ and the autocorrelogram amplitude was positively associated with IQ. A regression equation for predicting the level of nonverbal intelligence based on the power of theta- and beta-band oscillations, alpha-band oscillation indexes, and the amplitude and autocorrelation characteristics of the EEG signal was obtained.