Photo-physical mechanism of near-IR femtosecond laser-induced refractive-index change in PMMA.

Micromodification in bulk undoped polymethylmethacrylate (PMMA) by single focused (numerical aperture (NA) = 0.25), 1030-nm 250-fs laser pump pulses was explored by pump self-transmittance; optical, 3D-scanning confocal photoluminescence (PL); Raman micro-spectroscopy; and optical polarimetric and interferometric microscopy. Starting from the threshold pulse energy  = 0.

Evaluation of the agronomic traits and correlation analysis of phenotypes of proso millet (Panicum miliaceum L.) germplasm in Kazakhstan.

Proso millet is a valuable short-term crop of universal use cultivated all over the world. However, due to the lack of genetic improvement, the yield of this crop does not provide stable in-come for farmers. The research is aimed to test proso millet germplasm of different geographical origin under different agro-climatic regions in Kazakhstan.

Ugi bisamides based on pyrrolyl-β-chlorovinylaldehyde and their unusual transformations.

By one-pot four- and three-component Ugi reactions involving convertible isocyanides and unexplored pyrrole-containing β-chlorovinylaldehyde, a small library of 20 bisamides with unusual behavior in post-Ugi transformations was prepared and characterized. Surprisingly, a well-documented approach to obtain peptide-containing carboxylic acids through acid hydrolysis of the convertible isocyanide moiety in the Ugi bisamides proceeded in an unexpected manner in our case, leading to the formation of derivatives of amides of heterylidenepyruvic acid. An optimized synthetic protocol for this transformation was elaborated and a plausible sequence involving the elimination of the 2-chloroacetamide moiety and the conversion of the β-chlorovinyl fragment into a vinyl one is provided.

Phosphorylation of (Ser 291) in the linker insert of Syk negatively regulates ITAM signaling in platelets.

Receptor-induced tyrosine phosphorylation of spleen tyrosine kinase (Syk) has been studied extensively in hematopoietic cells. Metabolic mapping and high-resolution mass spectrometry, however, indicate that one of the most frequently detected phosphorylation sites encompassed S297 (S291 in mice) located within the linker B region of Syk. It has been reported that Protein kinase C (PKC) phosphorylates Syk S297, thus influencing Syk activity.

[Outcomes of extended depth of focus intraocular lenses implantation].

Unlabelled: Extended depth of focus (EDOF) intraocular lenses (IOLs) are the latest IOL designs. In recent years, several models of EDOF IOLs have become available in Russia, two of which (Tecnis Symfony and Acrysof IQ Vivity) are implanted in our clinic. Comparative studies devoted to the results of implantation of the new EDOF IOLs are rare in the available literature.

[Circumscribed choroidal hemangioma and non-pigmented choroidal melanoma: clinical, instrumental and molecular genetic features].

Unlabelled: Circumscribed choroidal hemangioma (CCH) and early non-pigmented choroidal melanoma (CM) have similar clinical, ultrasound and morphometric features, which in some cases makes their differential diagnosis difficult. There are few studies in the literature devoted to a comparative analysis of the molecular genetic features of CCH and non-pigmented CM, and the results of those studies are contradictory.

Purpose: This study attempts to develop a method of non-invasive molecular genetic differential diagnostics of CCH and non-pigmented CM.

Role of Tula-Family Proteins in Cell Signaling and Activation: Advances and Challenges.

This Special Issue entitled "Role of Tula-Family Proteins in Cell Signaling and Activation: Advances and Challenges" is focused on a relatively novel vertebrate gene/protein family termed alternatively TULA, UBASH3, or STS [...

The Pediatric and Young Adult Choroidal and Ciliary Body Melanoma Genetic Study, A Survey by the European Ophthalmic Oncology Group.

Purpose: To explore the genetic background of choroidal and ciliary body melanoma among children and young adults, with special focus on BAP1 germline variants in this age group.

Methods: Patients under the age of 25 and with confirmed choroidal or ciliary body melanoma were included in this retrospective, multicenter observational study. Nuclear BAP1 immunopositivity was used to evaluate the presence of functional BAP1 in the tumor.

VII Congress of Russian Biophysicists-2023, Krasnodar, Russia.

This special issue of Biophysical Reviews contains the materials presented at the VII Congress of Biophysicists of Russia, held from 17 to 23 April in Krasnodar. We believe that we have managed to prepare a selection of articles that well reflects the current state of biophysical science in Russia and its place in the world science. The VII Russian Congress on Biophysics was held in Krasnodar in April 2023, continuing the tradition of the series of biophysics conferences held every 4 years.

Photosystem II for photoelectrochemical hydrogen production.

Unlabelled: Water is a primary source of electrons and protons for photosynthetic organisms. For the production of hydrogen through the process of mimicking natural photosynthesis, photosystem II (PSII)-based hybrid photosynthetic systems have been created, both with and without an external voltage source. In the past 30 years, various PSII immobilization techniques have been proposed, and redox polymers have been created for charge transfer from PSII.

Biochemical characterization of spleen tyrosine kinase (SYK) isoforms in platelets.

Alternate splicing is among the regulatory mechanisms imparting functional diversity in proteins. Studying protein isoforms generated through alternative splicing is therefore critical for understanding protein functions in many biological systems. Spleen tyrosine kinase (Syk) plays an essential role in ITAM/hemITAM signaling in many cell types, including platelets.

Association of BARD1 and BRIP1 Gene Polymorphisms with the Risk of Uveal Melanoma.

Considering the limited information about the role of hereditary predisposition to the development of uveal melanoma, we have performed an analysis of the frequencies of BARD1 (rs1048108, rs2229571, rs2070094) and BRIP1 (rs4986764) gene polymorphisms in patients with uveal melanoma and benign choroidal nevus in comparison with healthy volunteers (control). It has been found that the minor alleles of BRIP1 rs4986764 and BARD1 rs2070094 polymorphisms, as well as the homozygosity of T allele at the BARD1 rs1048108 locus are common genetic markers for the predisposition to uveal melanoma and benign choroidal nevus, while the homozygous genotype GG for the BARD1 rs2229571 polymorphism is a specific marker for the predisposition to uveal melanoma and progressive choroidal nevus. We have also found that the heterozygous genotype at BARD1 rs1048108 polymorphic locus is a specific marker for protection against uveal melanoma and progressive choroidal nevus.

TULA Proteins in Men, Mice, Hens, and Lice: Welcome to the Family.

The two members of the UBASH3/STS/TULA protein family have been shown to critically regulate key biological functions, including immunity and hemostasis, in mammalian biological systems. Negative regulation of signaling through immune receptor tyrosine-based activation motif (ITAM)- and hemITAM-bearing receptors mediated by Syk-family protein tyrosine kinases appears to be a major molecular mechanism of the down-regulatory effect of TULA-family proteins, which possess protein tyrosine phosphatase (PTP) activity. However, these proteins are likely to carry out some PTP-independent functions as well.

Synthesis of imidazo[1,2-]pyridine-containing peptidomimetics by tandem of Groebke-Blackburn-Bienaymé and Ugi reactions.

Peptidomimetics with a substituted imidazo[1,2-]pyridine fragment were synthesized by a tandem of Groebke-Blackburn-Bienaymé and Ugi reactions. The target products contain substituted imidazo[1,2-]pyridine and peptidomimetic moieties as pharmacophores with four diversity points introduced from readily available starting materials, including scaffold diversity. A small focused compound library of 20 Ugi products was prepared and screened for antibacterial activity.

Phosphorylation of spleen tyrosine kinase at Y346 negatively regulates ITAM-mediated signaling and function in platelets.

Spleen tyrosine kinase (Syk) is expressed in a variety of hemopoietic cells. Upon phosphorylation of the platelet immunoreceptor-based activation motif of the glycoprotein VI (GPVI)/Fc receptor gamma chain collagen receptor, both the tyrosine phosphorylation and activity of Syk are increased leading to downstream signaling events. Although it has been established that the activity of Syk is regulated by tyrosine phosphorylation, the specific roles of individual phosphorylation sites remain to be elucidated.

TULA-Family Regulators of Platelet Activation.

The two members of the UBASH3/TULA/STS-protein family have been shown to critically regulate cellular processes in multiple biological systems. The regulatory function of TULA-2 (also known as UBASH3B or STS-1) in platelets is one of the best examples of the involvement of UBASH3/TULA/STS proteins in cellular regulation. TULA-2 negatively regulates platelet signaling mediated by ITAM- and hemITAM-containing membrane receptors that are dependent on the protein tyrosine kinase Syk, which currently represents the best-known dephosphorylation target of TULA-2.

An open call for contributions to a special issue of highlighting the research themes of VII Congress of Russian Biophysicists 2023.

We announce a call for contributions to a Special Issue of associated with the VII Congress of Russian Biophysicists (to be held in Krasnodar, Russia, 17-23 April 2023). The Congress is the main biophysical meeting held within Russia and is organized every four years. The Congress will focus on both the physical principles and mechanisms of biological processes occurring at different levels of structural organization, from molecular to cellular to organism and to population levels.

[Outcomes of bilateral implantation of trifocal and extended depth of focus IOLs].

Unlabelled: In recent years, a new class of extended depth of focus (EDOF) intraocular lenses (IOLs) has become available on the market. There is only a limited number of scientific papers comparing trifocal and EDOF IOL data, and the results are often contradictory.

Purpose: Comparative analysis of the results of trifocal and EDOF IOL implantation in patients with presbyopia and/or cataract.

Hydrogen Production by CO Deprived Photoautotrophic Chlamydomonas reinhardtii Cultures.

Light-dependent hydrogen production by microalgae attracts attention of researchers because of the potential practical application. It is generally recognized that Calvin-Benson-Bassham cycle competes with hydrogen production process for electrons, and substrate (CO2) limitation of the cycle can increase hydrogen production rate. Furthermore, photosystem II is not destroyed by CO2 deficiency.

Sodium Hypophosphite as a Bulk and Environmentally Friendly Reducing Agent in the Reductive Amination.

NaHPO was found to promote reductive amination. Being nontoxic, stable, environmentally benign, and available in bulk amounts, this reducing agent showed a powerful potential to compete with classical reductants applied in the target process. An factor of 1 was achieved for the substrate scope.

The relationship between photosystem II regulation and light-dependent hydrogen production by microalgae.

Certain microalgae species are capable of light-dependent hydrogen production under conditions of dark anaerobic incubation or nutrient deprivation. From the biotechnological point of view, this phenomenon is a process of synthesizing the energy carrier H while consuming light energy. Here, we overview the functional connection between the photosynthetic machinery and light-dependent hydrogen production and assess the physiological significance of this process.

"Microalgae as converters of light energy into biofuels and high-value products": a session of the Russian Photobiology Society 9th Congress (Shepsi, Krasnodar region, Russia; September, 12-19, 2021).

An outline of the "Microalgae as converters of light energy into biofuels and high-value products" section of the 9th Congress of the Russian Photobiological Society is presented. Key talks and poster presentations are briefly introduced along with key findings made by their authors. We conclude that this section was a success with many interesting talks and a vigorous follow-up discussion indicative of the keen interest of Russian researchers in microalgae and biotechnologies based on these microorganisms.

Commentary to "Biophotonics of molecules and nanoparticles": a session of the Russian Photobiology Society 9th Congress Shepsi, Krasnodar region, Russia; September 12-19, 2021.

Commentaries on the section "Biophotonics of molecules and nanoparticles" of the 9th Congress of the Russian Photobiological Society are presented. Presentations are briefly introduced along with the main conclusions made by their authors. This section included a plenary lecture, oral presentations, and posters with interesting talks and follow-up discussions.

Fluoride Additive as a Simple Tool to Qualitatively Improve Performance of Nickel-Catalyzed Asymmetric Michael Addition of Malonates to Nitroolefins.

Nowadays, design of the new chiral ligands for organometallic catalysts is often based on the step-by-step increase in their complexity to improve efficiency. Herein we describe that simple in situ addition of the fluoride source to the asymmetric organometallic catalyst can improve not only activity but also enantioselectivity. Bromide-nickel diimine complexes were found to catalyze asymmetric Michael addition in low yields and ee, but activation with fluoride leads to a significant improvement in catalyst performance.