Russie

Dans les années 1960, sont apparus deux centres sémiotiques d’importance : à Moscou (V.Vs. Ivanov, V.N. Toporov, V.A. Ouspenski et d’autres) et à Tartu (Y.M. Lotman, B.M. Gasparov, Z.G. Mintz). Mais on peut parler d’une seule école sémiotique de Moscou-Tartu (ou Tartu-Moscou) qui a réuni les chercheurs sur la base de principes communs concernant aussi bien son contenu que son organisation. Le courant sémiotique russe s’appuyait sur les travaux de divers prédécesseurs : l’école des « formalist..

The exine ultrastructure of Pretricolpipollenites bharadwajii from the Permian of Jordan

Dispersed trisulcate pollen grains of Pretricolpipollenites bharadwajii from the ?latest Permian of Jordan were studied with light, scanning, and transmission electron microscopy. The three sulci are located on the disal side. The median sulcus is usually longer, wider than the other two sulci, and has rounded aperture ends. The exine sculpturing and aperture membrane are scabrate. The ectexine includes a thick tectum, granular infratectum, and thin foot layer. The endexine is lamellate. A comparison with the closest similar genus Eucommiidites suggests overlapping characters; though the position of the three sulci on the distal side in Pretricolpipollenites bharadwajii and sulci on different sides in Eucommiidites indicates a possible distinguishing feature. Studies of exine ultrastructure of the other two Pretricolpipollenites species are needed to support or discard the distinction of Pretricolpipollenites and Eucommiidites

Some structural features of the peptide profile of myelin basic protein-hydrolyzing antibodies in schizophrenic patients

The antibodies of schizophrenic patients that hydrolyze myelin basic protein (MBP) have been actively studied recently, but the mechanism of the catalytic properties of immunoglobulin molecules remains unknown. Determination of specific immunoglobulin sequences associated with the high activity of MBP proteolysis will help to understand the mechanisms of abzyme catalysis. In the course of comparative mass spectrometric analysis of IgG peptides from the blood serum of patients with acute schizophrenia and healthy people, 12 sequences were identified, which were found only in antibodies that hydrolyze MBP. These sequences belong to IgG heavy chains and κ- and λ-type light chains, with eight of them belonging to variable domains. The content of peptides from the variable regions of the light chains does not correlate with the proteolytic activity of IgG to MBP in patients with schizophrenia, whereas for two sequences from the variable regions of the heavy chains (FQ(+0.98)GWVTMTR and *LYLQMN(+0.98)SLR), an increase in activity with increasing their concentration. The results suggest that these sequences may be involved in one way or another in MBP hydrolysis

Evaluation of Haptoglobin and Its Proteoforms as Glioblastoma Markers

Haptoglobin (Hp) is a blood plasma glycoprotein that plays a critical role in tissue protection and the prevention of oxidative damage. Haptoglobin is an acute-phase protein, its concentration in plasma changes in pathology, and the test for its concentration is part of normal clinical practice. Haptoglobin is a conservative protein and is the subject of research as a potential biomarker of many diseases, including malignant neoplasms. The Human Hp gene is polymorphic and controls the synthesis of three major phenotypes—homozygous Hp1-1 and Hp2-2, and heterozygous Hp2-1, determined by a combination of allelic variants that are inherited. Numerous studies indicate that the phenotype of haptoglobin can be used to judge the individual’s predisposition to various diseases. In addition, Hp undergoes various post-translational modifications (PTMs). Glioblastoma multiform (GBM) is the most malignant primary brain tumor. In our study, we have analyzed the state of Hp proteoforms in plasma and cells using 1D (SDS-PAGE) and 2D electrophoresis (2DE) with the following mass spectrometry (LC ES-MS/MS) or Western blotting. We found that the levels of α2- and β-chain proteoforms are up-regulated in the plasma of GBM patients. An unprocessed form of Hp2-2 (PreHp2-2, zonulin) with unusual biophysical parameters (pI/Mw) was also detected in the plasma of GBM patients and glioblastoma cells. Altogether, this data shows the possibility to use proteoforms of haptoglobin as a potential GBM-specific plasma biomarker

Synthesis and Biological Evaluation of New Isoxazolyl Steroids as Anti-Prostate Cancer Agents

Steroids with a nitrogen-containing heterocycle in the side chain are known as effective inhibitors of androgen signaling and/or testosterone biosynthesis, thus showing beneficial effects for the treatment of prostate cancer. In this work, a series of 3β-hydroxy-5-ene steroids, containing an isoxazole fragment in their side chain, was synthesized. The key steps included the preparation of Weinreb amide, its conversion to acetylenic ketones, and the 1,2- or 1,4-addition of hydroxylamine, depending on the solvent used. The biological activity of the obtained compounds was studied in a number of tests, including their effects on 17α-hydroxylase and 17,20-lyase activity of human CYP17A1 and the ability of selected compounds to affect the downstream androgen receptor signaling. Three derivatives diminished the transcriptional activity of androgen receptor and displayed reasonable antiproliferative activity. The candidate compound, 24j (17R)-17-((3-(2-hydroxypropan-2-yl)isoxazol-5-yl)methyl)-androst-5-en-3β-ol, suppressed the androgen receptor signaling and decreased its protein level in two prostate cancer cell lines, LNCaP and LAPC-4. Interaction of compounds with CYP17A1 and the androgen receptor was confirmed and described by molecular docking