Evaluation of the size of the microsphere loss from the myocardium in rats in a chronic experiment

The loss of radioactive microspheres (15 microns in diameter) from the rat myocardium was investigated during chronic experiment. Microspheres were injected to donor rats, the hearts were removed 20-30 min later and the number of microspheres trapped in the heart was determined on gamma-counter. After that the hearts were transplanted into the abdominal cavity of recipient rats using microsurgery technique. 5-24 days later the recipients were killed, the transplanted hearts were removed and radioactivity was measured again. It was shown that not more than 10% of microspheres were lost from the myocardium over a 5-24-day period, with the value of microsphere loss independent of the time period.     

A new destruction of blood group substances. Isolation of glycopeptide containing O-glycosidic carbohydrate-peptide linkage

Degradation of blood group substances using chemical and enzymatic methods has been carried out. A glycopeptide with an O-glycosidic carbohydrate-peptide linkage has been isolated for the first time from biopolymers of such a type. It's structure has been determined as O-(N-acetyl-galactosaminyl)-Thr-Ala.     

A quantitative evaluation of the reactive and dystrophic changes in the cerebellar cortex of mice during malnutrition and subsequent food rehabilitation]

Neurones with chromatolysis, hyperchromatism and numerous nucleus have been counted of the paraffin cerebellar cortex sections coloured with kresil-violet and metil-green pironin. The alimentary deficiency has been shown to result in increase of cell number with chromatolysis and hyperchromatism and decrease of the number of numerous nucleus. The food rehabilitation doesn't take off completely damages caused by malnutrition. The use of carnitine leads to the complete rehabilitation that is due to the normalization of protein metabolism in cerebellum.     

Cluster of point mutations predetermined by a quasipalindromic nucleotide sequence in plasmid pBR322 DNA

Development of a cluster of point mutations due to the correction of an imperfect hairpin in plasmid DNA was investigated. Plasmid pBR322 DNA containing opposite double-strand DNA lesions in the region of a quasipalindrome was constructed. For this aim plasmid DNA was cleaved at the BamHI site, and cytosine residues of the sticky ends were modified by O-methylhydroxylamine. Modified linearized plasmid DNA was ligated and used for transformation of E.coli cells. Tetracycline-sensitive transformants were selected, and the mutants were characterized by restriction and sequencing analysis. One mutant contained a cluster of point mutations. The distribution of mutations was consistent with the cluster having arisen through correction of the imperfect hairpin formed by the quasipalindrome.     

Principles of Calcium Signal Generation and Transduction in Plant Cells

Calcium ions exhibit unique properties and a universal ability to transmit diverse signals in plant cells under the primary action of hormones, pathogens, light, gravity, and various abiotic stressors. In the last few years, considerable progress has been achieved in deciphering the mechanisms of Ca²⁺ involvement in the regulation of plant responses. Recent studies revealed the genes encoding Ca²⁺-permeable channels that conduct Ca²⁺ currents across the membranes during the transduction of the Ca²⁺ signal. These proteins comprise the ligand-gated Ca²⁺-permeable channels activated by cyclic nucleotides (CNGC) and amino acids (glutamate receptor-like channels, GLR), the voltage-gated tonoplast channel (two-pore channel, TPC1), mechanosensitive channels (MSL, MCA, OSCA1), and annexins. The role of Ca²⁺-ATPase and Ca²⁺/H⁺-exchangers in the active extrusion of excess cytoplasmic Ca²⁺ into the apoplast or cell organelles was examined in detail. The calmodulins (CaM), CaM-like proteins (CML), Ca²⁺-dependent protein kinases (CDPK), and complexes of calcineurin-B-like proteins (CBL) with CBL-interacting protein kinases (CIPK) were found to produce intricate signaling networks that decode Ca²⁺ signals and elicit plant responses to external stimuli. This review analyzes the data accumulated over the past decade on the principles of formation and propagation of the calcium signal in plant cells.     

Collision of Ion-Acoustic Solitary Waves in Plasma

The process of collision of ion-acoustic solitary waves in a collisionless plasma with cold ions and Boltzmann electrons is studied using numerical simulations. It is shown that solitary waves with sufficiently large amplitudes do not preserve their identity after the collision. Their amplitudes decrease, and the shapes change. It is found that the collision is accompanied by the generation of fast ions with velocities exceeding threefold the ion sound speed.     

角蝉科一新属一新种

角蝉科的昆虫,是世界著名的富于拟态性的昆虫。它们的畸形发达的前胸背板给人们以明显的识别的特征。这一科不少种类是果树、森林或农业的重要害虫,造成相当严重的灾害。角蝉科截至目前为止,全世界已记载的共324属2500余种;中国已知的20属152种。 本文记述角蝉科一新属及一新种。     

Look who’s talking—the crosstalk between oxidative stress and autophagy supports exosomal-dependent release of HCV particles

Autophagy is a highly conserved and regulated intracellular lysosomal degradation pathway that is essential for cell survival. Dysregulation has been linked to the development of various human diseases, including neurodegeneration and tumorigenesis, infection, and aging. Besides, many viruses hijack the autophagosomal pathway to support their life cycle. The hepatitis C virus (HCV), a major cause of chronic liver diseases worldwide, has been described to induce autophagy. The autophagosomal pathway can be further activated in response to elevated levels of reactive oxygen species (ROS). HCV impairs the Nrf2/ARE-dependent induction of ROS-detoxifying enzymes by a so far unprecedented mechanism. In line with this, this review aims to discuss the relevance of HCV-dependent elevated ROS levels for the induction of autophagy as a result of the impaired Nrf2 signaling and the described crosstalk between p62 and the Nrf2/Keap1 signaling pathway. Moreover, autophagy is functionally connected to the endocytic pathway as components of the endosomal trafficking are involved in the maturation of autophagosomes. The release of HCV particles is still not fully understood. Recent studies suggest an involvement of exosomes that originate from the endosomal pathway in viral release. In line with this, it is tempting to speculate whether HCV-dependent elevated ROS levels induce autophagy to support exosome-mediated release of viral particles. Based on recent findings, in this review, we will further highlight the impact of HCV-induced autophagy and its interplay with the endosomal pathway as a novel mechanism for the release of HCV particles.