Dynamics of non-covalent interactions during the P-O bond cleavage reaction by ribonuclease A.

In this work, an atomistic-scale investigation of the phosphodiester P-O bond cleavage reaction by the enzyme ribonuclease A was carried out using computer simulation techniques. It is shown that during the reaction the network of non-covalent interactions in the active center of the ribonuclease changes significantly, while the role of these non-covalent interactions is different: coordination of the corresponding groups, electron density transfer, and ligand holding in the active center. It is shown that the process of proton transfer from Asp121 to His119 is the first stage of this reaction; at the same time, the hydrogen bond between the phosphate ligand and the imino group of Arg39 is broken, which, although keeping the ligand in the active center, does not allow the ligand to orient itself more conveniently for subsequent proton transfers.

[Dinityrosyl Iron Complexes with Thiol-Containing Ligands as a Functionally Active "Working Form" of Nitric Oxide System in Living Organisms: A Review].

Experimental data were summarized to assume that dinitrosyl iron complexes (DNICs) with thiol-containing ligands are an endogenous "working form" of the nitric oxide (NO) system in living organisms. DNICs can function as donors of both neutral NO molecules, which are responsible for positive regulatory effects of the NO system on various physiological and biochemical processes in humans and animals, and nitrosonium cations (NO^(+)), which are responsible mostly for negative cytotoxic activity of the system. Special attention is paid to the finding that DNICs, especially in combination with dithiocarbamate derivatives, suppress SARS-CoV-2 infection in Syrian hamsters.

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.

Dynamics of γ-aminobutyric acid concentration in the human brain in response to short visual stimulation.

Objective: To find a possible quantitative relation between activation-induced fast (< 10 s) changes in the γ-aminobutyric acid (GABA) level and the amplitude of a blood oxygen level-dependent contrast (BOLD) response (according to magnetic resonance spectroscopy [MRS] and functional magnetic resonance imaging [fMRI]).

Materials And Methods: fMRI data and MEGA-PRESS magnetic resonance spectra [echo time (TE)/repetition time (TR) = 68 ms/1500 ms] of an activated area in the visual cortex of 33 subjects were acquired using a 3 T MR scanner. Stimulation was performed by presenting an image of a flickering checkerboard for 3 s, repeated with an interval of 13.

β-(1 → 3)(1 → 6)glucan from Schizophyllum commune 227E.32: High yield production via glucose/xylose co-metabolization.

A co-metabolization of xylose and glucose by Schizophyllum commune 227E.32 wild mushroom for exopolysaccharide (EPS) production is presented. Cultivations performed with S.

Graft and Patient Survival in Kidney Transplant with Deceased Donor Using KDRI (Kidney Donor Risk Index), KDPI (Kidney Donor Profile Index), and EPTS (Estimated Post-Transplant Survival) in Colombia.

BACKGROUND EPTS (Estimated Post-Transplant Survival), KDRI (Kidney Donor Risk Index), and KDPI (Kidney Donor Profile Index) were developed aiming to ameliorate donor-recipient longevity matching in kidney transplants. They are based on a prediction model made using the United States population; evidence of their use outside EEUU remains limited. The aim of this study was to describe the quality of deceased-donor kidneys and to determine recipient and graft survival, glomerular filtration rate, and incidence of delayed graft function in renal transplantation according to these indices in Cali, Colombia.

Cannabis sativa-based oils against aluminum-induced neurotoxicity.

The use of terpenoid compounds in different neural-related conditions is becoming useful for several illnesses. Another possible activity of these compounds is the reduction of nervous impairment. Cannabis sativa plants are known for their concentration of two important terpenoids, the delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD).

Neurotoxicological effects of venlafaxine on Caenorhabditis elegans and Danio rerio.

The growing consumption of psychoactive drugs, such as Venlafaxine (VFX), can negatively affect the organisms. Our main hypothesis is to investigate if VFX at human-used doses could exert effects on the behavioral, nervous, and antioxidant systems of two different organisms, zebrafish and C. elegans.

Biochar-immobilized Bacillus spp. for heavy metals bioremediation: A review on immobilization techniques, bioremediation mechanisms and effects on soil.

Heavy metals contamination present risks to ecosystems and human health. Bioremediation is a technology that has been applied to minimize the levels of heavy metals contamination. However, the efficiency of this process varies according to several biotic and abiotic aspects, especially in environments with high concentrations of heavy metals.

Beneficial Effects of Dinitrosyl Iron Complexes on Wound Healing Compared to Commercial Nitric Oxide Plasma Generator.

Nitric oxide (NO) is a gaseous molecule which plays a key role in wound healing. Previously, we identified the optimal conditions for wound healing strategies using NO donors and an air plasma generator. The aim of this study was to compare the wound healing effects of binuclear dinitrosyl iron complexes with glutathione (B-DNIC-GSH) and NO-containing gas flow (NO-CGF) at their optimal NO doses (0.

Human rights violations in normalizing procedures on intersex children.

Intersex children in Brazil are still subjected to "normalizing" surgical procedures and subsequent bodily interventions to make their bodies conform to binary views of sex. Resolution n. 1,664/2003 of the Brazilian Federal Council of Medicine legitimizes interventions upon intersex bodies, being the only national normative instrument that address the subject.

The Cytostatic Action of Dinitrosyl Iron Complexes with Glutathione on Cells Is Mediated by Nitrosonium Cations Released from These Complexes.

This study demonstrates a bacteriostatic effect of binuclear dinitrosyl iron complexes with glutathione on TN300 cells. It has been quantified by the colony formation assay. The bacteriostatic effect exerted by these complexes increases considerably in the presence of diethyldithiocarbamate.

Antiviral Activity of Nitrosonium Cations against SARS-CoV-2 on a Syrian Hamster Model.

The antiviral action of binuclear dinitrosyl iron complexes with glutathione along with diethyldithiocarbamate against the SARS-CoV-2 virus has been demonstrated on a Syrian hamster model after aerosol exposure of SARS-CoV-2-infected animals to the solutions of said compounds. EPR assays in analogous experiments on intact hamsters have demonstrated that the iron complexes and diethyldithiocarbamate are predominantly localized in lung tissues. These results have been compared with similar measurements on intact mice, which have shown the equal localization of these agents in both the lungs and liver.

Positive (Regulatory) and Negative (Cytotoxic) Effects of Dinitrosyl Iron Complexes on Living Organisms.

The proposed in our studies mechanism of dinitrosyl iron complex (DNIC) formation through the main step of disproportionation of two NO molecules in complex with Fe2+ ion leads to emergence of the resonance structure of dinitrosyl-iron fragment of DNIC, [Fe2+(NO)(NO)]. The latter allowed suggesting capacity of these complexes to function as donor of both neutral NO molecules as well as nitrosonium cations (NO), which has been demonstrated in experiments. Analysis of biological activity of DNICs with thiol-containing ligands presented in this review demonstrates that NO molecules and nitrosonium cations released from the complexes exert respectively positive (regulatory) and negative (cytotoxic) effects on living organisms.

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.

Why do patients with low back pain seek care at emergency department? A cross-sectional study.

Background: It is unclear why patients with low back pain seek care in emergency departments.

Objectives: We aim to describe the demographic, physical, and psychological characteristics, and reasons for seeking care at emergency departments due to an episode of low back pain.

Methods: This is a cross-sectional study conducted in an emergency department of a public hospital in São Paulo, Brazil, from September 2018 to May 2019.

Household prallethrin-based insecticide toxicity on different C. elegans life stage: A possible sign of Huntington Disease.

Household insecticide is largely used for insect and ectoparasite control, in city centers as well as in the countryside. The pyrethroids are the most used class of insecticide, these compounds in low doses have low toxicity for mammalians, in comparison to other compounds, with insecticide effects. The contact of these compounds in sublethal doses begins in early life and many cases, in intrauterine life.

Dietary transference of 17α-ethinylestradiol changes the biochemical and behavioral biomarkers in adult zebrafish (Danio rerio).

The endocrine disruptors (ED), even in low concentration, can change the homeostasis of an organism through the biochemical and physiological pathways; and are gaining more relevance due to their well-reported presence in the natural environment. EDs mainly affect non-target animals, which can bioaccumulate, leading to changes in metabolism. Another problem is due to several organisms that compose the aquatic biota serving as a basis of the food chain and transferring it to higher trophic levels.

Neuroprotective potential of Cannabis sativa-based oils in Caenorhabditis elegans.

Substances from the Cannabis sativa species, especially cannabidiol (CBD) and Delta-9-tetrahydrocannabinol (Δ9-THC), have attracted medical attention in recent years. The actions of these two main cannabinoids modulate the cholinergic nervous system (CholNS) involving development, synaptic plasticity, and response to endogenous and environmental damage, as a characteristic of many neurodegenerative diseases. The dynamics of these diseases are mediated by specific neurotransmitters, such as the GABAergic nervous system (GNS) and the CholNS.

Photobiomodulation Therapy Combined with Static Magnetic Field Reduces Pain in Patients with Chronic Nonspecific Neck and/or Shoulder Pain: A Randomized, Triple-Blinded, Placebo-Controlled Trial.

Photobiomodulation therapy (PBMT) has been used to treat patients with chronic neck and/or shoulder pain. However, it is unknown whether the concurrent use of PBMT and static magnetic field (PBMT-sMF) also has positive effects in these patients. The aim of this study was to investigate the effects of PBMT-sMF versus placebo on pain intensity, range of motion (ROM) and treatment satisfaction in patients with chronic nonspecific neck and/or shoulder pain.

Management of acute low back pain in emergency departments in São Paulo, Brazil: a descriptive, cross-sectional analysis of baseline data from a prospective cohort study.

Objective: To describe management strategies used in public emergency departments in a middle-income country for patients with acute non-specific low back pain.

Design: A descriptive, cross-sectional analysis of baseline data from a prospective cohort study.

Setting And Participants: A study with 600 patients with low back pain presenting in four public emergency departments from São Paulo, Brazil was conducted.

Neuroprotective and antioxidant effects of pitaya fruit on Cu-induced stress in adult zebrafish.

The harmful effects of heavy metals on organisms have not been fully described. At present, there is a close relationship between neurodegenerative diseases and copper toxicity. In addition, the copper effect on the central nervous system is followed by high levels of free radicals in different body tissues.

Synthetic estrogen bioaccumulates and changes the behavior and biochemical biomarkers in adult zebrafish.

Estrogen is considered to be an endocrine disrupter and is becoming increasingly more prevalent in the daily life of humans. In some cases, estrogen is not fully metabolized by organisms and may be excreted in either its original form or in organic complex forms, into water residue systems reaching concentrations of 0.05 ng.

Spray with Nitric Oxide Donor Accelerates Wound Healing: Potential Off-the-Shelf Solution for Therapy?

Background: Ditrosyl iron complexes (DNIC) are endogenous donors of nitric oxide. The possibility of their application to stimulate regeneration has been studied for more than 15 years. However, the most effective dose and form of delivery have not yet been determined.

High Dose Inhalation with Gaseous Nitric Oxide in COVID-19 Treatment.

A method of treatment of a new coronavirus infection COVID-19 in patients undergoing high flow oxygenation is proposed and technically implemented; the method is based on high-dose inhalation of gaseous nitric oxide (NO) with the patient's spontaneous breathing. The results of the treatment of this disease demonstrating the high efficiency of the new method are presented. A possible mechanism of the blocking effect of high doses of inhaled nitric oxide on the replication of the SARS-CoV-2 virus is discussed; it is based on the formation of dinitrosyl iron complexes in the respiratory tract and lungs of COVID-19 patients with thiol-containing ligands acting as donors of NO and nitrosonium NO cations in a living organism that have a cytotoxic effect on the SARS CoV-2 virus.