Phenomenon of music-induced opening of the blood-brain barrier in healthy mice

Music plays a more important role in our life than just being an entertainment. For example, it can be used as an anti-anxiety therapy of human and animals. However, the unsafe listening of loud music triggers hearing loss in millions of young people and professional musicians (rock, jazz and symphony orchestra) owing to exposure to damaging sound levels using personal audio devices or at noisy entertainment venues including nightclubs, discotheques, bars and concerts. Therefore, it is important to understand how loud music affects us. In this pioneering study on healthy mice, we discover that loud rock music below the safety threshold causes opening of the blood-brain barrier (OBBB), which plays a vital role in protecting the brain from viruses, bacteria and toxins. We clearly demonstrate that listening to loud music during 2 h in an intermittent adaptive regime is accompanied by delayed (1 h after music exposure) and short-lasting to (during 1–4 h) OBBB to low and high molecular weight compounds without cochlear and brain impairments. We present the systemic and molecular mechanisms responsible for music-induced OBBB. Finally, a revision of our traditional knowledge about the BBB nature and the novel strategies in optimizing of sound-mediated methods for brain drug delivery are discussed.     

Endophytic bacteria of Sphagnum mosses as promising objects of agricultural microbiology

Sphagnum mosses serve as a unique habitat for microorganisms, which play an important role both for the host plants and the peatland ecosystems. The aim of the present study was to isolate endophytic bacteria from the tissues of Sphagnum mosses and to screen them for strains promising for further application in agricultural microbiology. About 50 samples of Sphagnum fallax (H. Klinggr.) H. Klinggr. and Sphagnum magellanicum Brid. were collected in the Austrian Alps and the Lenindgrad Region of Russia in 2009–2010. Endophytic bacteria were detected inside the moss plants using fluorescent in situ hybridization (FISH) followed by confocal laser scanning microscopy (CLSM). Altogether, 283 isolates were obtained by cultivation on the nutrient media. Examination of the isolates for the antagonistic activity revealed that more than 50% of them could suppress the growth of phytopathogenic and toxigenic fungi. More than 30% of isolates showed some antagonistic activity against microbial phytopathogens. The isolated strains could colonize crops and promote their growth. Molecular-genetic identification coupled with physiological/biochemical characterization showed that the dominant endophytic groups belonged to the genera Burkholderia, Pseudomonas, Flavobacterium, Serratia and Collimonas. The isolated endophytes were shown to be promising objects for the development of effective growth-promoting and protective microbiological preparations to be used in agriculture.     

How does a tigress balance the opposing constraints of raising cubs?

Mammal Research - The persistence of wildlife populations largely depends on females successfully rearing young through the earliest, most vulnerable period. During this period, mothers must...     

Electron microscopic study of the interaction between neoplastic fibroblasts and the substrate in tissue culture]

Electron microscope study of neoplastic L fibroblasts was carried out in 15, 30, 60, and 90 min after their attachment to solid substratum. Comparative analysis of neoplastic and normal fibroblasts at the same stages was carried out. Spreading rate of L fibroblasts proved slower than that of normal fibroblasts. Primary reaction of neoplastic cells was disturbed on the contact with substratum: it was morphologically manifested in changing of structure of the cell lower surface. Bundles of microfilaments were absent from the neoplastic fibroblasts' cytoplasm. The above changes, apparently, may entail the lesser degree of spreading and the weaker attachement of neoplastic fibroblasts to the substratum.     

2H-NMR comparative study of phosphocholine group conformation in bilayers composed of diacyl and dialkyl phosphatidylcholines

Model membranes formed from 1,2-dihexadecyl-, 1,2-dipalmitoyl-, 1,2-ditetradecyl- or 1,2-dimyristoyl-rac-glycero-3-phosphocholine, deuterium-labelled at choline groups, in an excess of water were compared using 2H-NMR spectroscopy. The dynamics and conformation of the labelled choline segments were estimated based on spin-lattice relaxation time and residual quadrupole splittings. The trimethylammonium group of dialkyl phosphatidylcholine was shown to be more distant from the bilayer surface as compared with that of the diacyl analogues.     

Chromatin folding in human spermatozoa. I. Dynamics of chromatin remodelling in differentiating human spermatids

Changes in chromatin structure at different stages of differentiation of human spermatids were studied. It was shown that, in nuclei of early spermatids, chromatin is loosely packed and its structural element is an 8-nm fiber. This “elementary” fiber is predominant at the initial stages of differentiation; in the course of maturation, it is replaced by globular elements approximately 60 nm in diameter. In intermediate spermatids, these globules start to condense into fibrillar aggregates and reduce their diameter to 30–40 nm. At all stages of spermatid maturation, except the final stages, these globules are convergence centers for elementary fibers. This remodelling process is vectored and directed from the apical (acrosomal) to the basal pole of the nucleus. In mature spermatids, the elementary 8-nm fibers are almost absent and the major components are 40-nm fibrillar aggregates. The nuclei of mature spermatids are structurally identical with the nuclei of spermatozoa with the so-called “immature chromatin,” which are commonly found in a low proportion in sperm samples from healthy donors and may prevail over the normal cells in spermiogenetic disorders. The cause of this differentiation blockade remains unknown. Possibly, the formation of intermolecular bonds between protamines, which are required for the final stages of chromatin condensation, is blocked in a part of spermatids. The results of this study are discussed in comparison with the known models of nucleoprotamine chromatin organization in human spermatozoa.     

Ethylene-Induced Activation of Xylanase in Adventitious Roots of Maize as a Response to the Stress Effect of Root Submersion

Submersion of roots of ten-day-old maize (Zea maysL.) seedlings was accompanied by a decrease in pO₂and an increase in pCO₂of the medium adjacent to the roots. These changes stimulated ethylene evolution in intact plants. Enhanced biosynthesis of ethylene was accompanied by xylanase activation in adventitious roots. As a result, an enhanced formation of aerenchyma was observed in the cortex of adventitious roots. Therefore, these processes resulted in the development of a ventilation system by which O₂can reach the root system exposed to hypoxia. The volume of aerenchyma was assessed by the volume of gas cavities (porosity). In contrast to the main root, the growth of adventitious roots was not inhibited under these conditions. Enlargement of the stem base and increase in the number of aerenchymatous adventitious roots facilitated the oxygen supply to the submerged organs of the plants.     

Hemopoiesis on Stromal Sublayers Formed by Constant Lines of Fibroblasts

We studied the formation of hemopoietic colonies on an artificial sublayer in the peritoneal cavity of mice under the influence of stromal sublayers consisting of fibroblasts of six constant cell limes. All studied lines of stromal cells supported the formation of granulocytic foci and some of them supported the formation of erythroid foci as well. It was shown that hemopoiesis was preserved or, in some cases, enhanced on sublayers of fixed (metabolically inactive) cells. The treatment of fibroblasts by E. coli lipopolysaccharide did not lead, as a rule, to significant stimulation of hemopoiesis.     

“Microbiological aging” by Mechnikov. How to interpret these ideas today?

Mechnikov’s hypothesis that the key to prolongation of life lies in the introduction of useful microflora to the gut was not proved. Any microflora needs nutrition and perceives the human body only as a nutrient substrate. Destruction of the basement membranes, that delimit the epithelium contacting with aggressive microbiological environment from the deeper parts of the body, can lead to chronic inflammatory diseases and aging of the skin as a consequence of invasion of microorganisms. At the ultrastructural level this has been shown by the example of prostatitis and skin aging changes. Coupled with the penetration of germs, a flux of immune cells may cause autoimmune reactions due to abrupt changes in the molecular design during intermembrane transport. Thus, the physiological process of macroorganism aging can be viewed as a consequence of its microbiological destruction.