Simultaneous determination of cystine and other free aminothiols in blood plasma using capillary electrophoresis with pH-mediated stacking.

We developed a method of sensitive capillary electrophoresis using UV detection for the determination of certain free aminothiols (reduced cysteinylglycine (rCysGly), cysteine (rCys), glutathione (rGln), and cystine (CysS) in human blood plasma. The reduced thiols were derivatized with N-ethylmaleimide. The plasma was purified from proteins via ultrafiltration. Electrophoretic separation was performed using 115 mM Na phosphate with 7.5% (v/v) polyethylene glycol 600, pH 2.3. The in-capillary concentration of the analytes was achieved with a pH gradient created via the preinjection of triethanolamine and postinjection of phosphoric acid. The separation was carried out using a silica capillary (50 µm i.d.; total/effective separation length 42/35 cm) at a 25 kV voltage. The total analysis/regeneration time was 18 min. The quantification limits varied from 1.3 µM (rCysGly) to 5.4 µM (CysS). The accuracy was 95%-99%, and the repeatability and reproducibility were approximately 1.8%-3.8% and 1.9%-5.0%, respectively. An analysis of plasma samples from healthy volunteers (N = 41) showed that the mean levels of rCysGly, rCys, rGln, and CysS were 1.64, 10.6, 2.58, and 46.2 µM, respectively.

The Expression of Cell Cycle Cyclins in a Human Megakaryoblast Cell Line Exposed to Simulated Microgravity.

The study of the physiological and pathophysiological processes under extreme conditions facilitates a better understanding of the state of a healthy organism and can also shed light on the pathogenesis of diseases. In recent years, it has become evident that gravitational stress affects both the whole organism and individual cells. We have previously demonstrated that simulated microgravity inhibits proliferation, induces apoptosis, changes morphology, and alters the surface marker expression of megakaryoblast cell line MEG-01. In the present work, we investigate the expression of cell cycle cyclins in MEG-01 cells. We performed several experiments for 24 h, 72 h, 96 h and 168 h. Flow cytometry and Western blot analysis demonstrated that the main change in the levels of cyclins expression occurs under conditions of simulated microgravity after 96 h. Thus, the level of cyclin A expression showed an increase in the RPM group during the first 4 days, followed by a decrease, which, together with the peak of cyclin D, may indicate inhibition of the cell cycle in the G2 phase, before mitosis. In addition, based on the data obtained by PCR analysis, we were also able to see that both cyclin A and cyclin B expression showed a peak at 72 h, followed by a gradual decrease at 96 h. STED microscopy data also confirmed that the main change in cyclin expression of MEG-01 cells occurs at 96 h, under simulated microgravity conditions, compared to static control. These results suggested that the cell cycle disruption induced by RPM-simulated microgravity in MEG-01 cells may be associated with the altered expression of the main regulators of the cell cycle. Thus, these data implicate the development of cellular stress in MEG-01 cells, which may be important for proliferating human cells exposed to microgravity in real space.

Differential Expression of Subsets of Genes Related to HDL Metabolism and Atherogenesis in the Peripheral Blood in Coronary Artery Disease.

Differential expression of genes (DEGs) in coronary artery disease (CAD) and the association between transcript level and high-density lipoprotein cholesterol (HDL-C) were studied with 76 male patients with CAD and 63 control patients. The transcript level of genes related to HDL metabolism (24 genes) and atherosclerosis-prone (41 genes) in RNA isolated from peripheral blood mononuclear cells was measured by real-time RT-PCR. Twenty-eight DEGs were identified. The expression of cholesterol transporters, ALB, APOA1, and LCAT was down-regulated, while the expression of AMN, APOE, LDLR, LPL, PLTP, PRKACA, and CETP was up-regulated. The systemic inflammation in CAD is evidenced by the up-regulation of IL1B, TLR8, CXCL5, and TNFRSF1A. For the controls, TLR8 and SOAT1 were negative predictors of the HDL-C level. For CAD patients, PRKACG, PRKCQ, and SREBF1 were positive predictors, while PRKACB, LCAT, and S100A8 were negative predictors. For CAD patients, the efficiency of reverse cholesterol transport is 73-79%, and intracellular free cholesterol seems to accumulate at hyperalphalipoproteinemia. Both atheroprotective (via S100A8) and proatherogenic (via SREBF1, LCAT, PRKACG, PRKACB, and PRKCQ) associations of gene expression with HDL-C determine HDL functionality in CAD patients. The selected key genes and involved pathways may represent HDL-specific targets for the diagnosis and treatment of CAD and atherosclerosis.

Macrophages derived from LPS-stimulated monocytes from individuals with subclinical atherosclerosis were characterized by increased pro-inflammatory activity.

OBJECTIVE: Atherosclerosis is characterized by chronic inflammation in the vascular wall. Currently the violation of immune tolerance of innate immune cells is considered as a possible mechanism of chronification of inflammation. The aim of this study is to assess the inflammatory activity and tolerance of monocytes and macrophages in subclinical atherosclerosis. METHODS: A total of 55 individuals free from clinical manifestations of atherosclerosis-associated cardiovascular disease with a presence or absence of atherosclerotic plaques in the carotid arteries were included in this study. CD14+ monocytes were isolated from individuals' blood and stimulated with a single dose of lipopolysaccharide (LPS) on day 1 or with double doses of LPS on day 1 and day 6. The secretion of cytokines TNF, IL-1ß, IL-6, IL-8, IL-10 and CCL2 were evaluated using ELISA. RESULTS: Our findings demonstrate that macrophages derived from LPS-stimulated monocytes in individuals with subclinical atherosclerosis exhibited increased secretion of IL-6, IL-10 and CCL2, which was associated with intima-media thickness, body mass index, but not with individuals' age. Moreover, macrophages from individuals with atherosclerotic plaques exhibited impaired tolerance towards the second LPS stimulation manifested by elevated secretion of the chemoattractant CCL2. CONCLUSION: Increased secretion of these cytokines by macrophages may contribute to chronic local inflammation in the vascular wall by recruiting other immune cells.

The Role of Impaired Mitochondrial Transport in the Development of Neurodegenerative Diseases.

The fight against neurodegenerative diseases is one of the key direction of modern medicine. Unfortunately, the difficulties in understanding the factors underlying the development of neurodegeneration hinder the development of breakthrough therapeutics that can stop or at least greatly slow down the progression of these diseases. In this review, it is considered the disruption of mitochondrial transport as one of the pathogenesis factors contributing to neurodegeneration using the examples of Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease. Here, the mechanism of mitochondrial transport under normal conditions and the mechanisms of disturbances for the indicated diseases will be considered.

Atheroprotective Aspects of Heat Shock Proteins.

Atherosclerosis is a major global health problem. Being a harbinger of a large number of cardiovascular diseases, it ultimately leads to morbidity and mortality. At the same time, effective measures for the prevention and treatment of atherosclerosis have not been developed, to date. All available therapeutic options have a number of limitations. To understand the mechanisms behind the triggering and development of atherosclerosis, a deeper understanding of molecular interactions is needed. Heat shock proteins are important for the normal functioning of cells, actively helping cells adapt to gradual changes in the environment and survive in deadly conditions. Moreover, multiple HSP families play various roles in the progression of cardiovascular disorders. Some heat shock proteins have been shown to have antiatherosclerotic effects, while the role of others remains unclear. In this review, we considered certain aspects of the antiatherosclerotic activity of a number of heat shock proteins.

Novel Molecular Vehicle-Based Approach for Cardiac Cell Transplantation Leads to Rapid Electromechanical Graft-Host Coupling.

Myocardial remodeling is an inevitable risk factor for cardiac arrhythmias and can potentially be corrected with cell therapy. Although the generation of cardiac cells ex vivo is possible, specific approaches to cell replacement therapy remain unclear. On the one hand, adhesive myocyte cells must be viable and conjugated with the electromechanical syncytium of the recipient tissue, which is unattainable without an external scaffold substrate. On the other hand, the outer scaffold may hinder cell delivery, for example, making intramyocardial injection difficult. To resolve this contradiction, we developed molecular vehicles that combine a wrapped (rather than outer) polymer scaffold that is enveloped by the cell and provides excitability restoration (lost when cells were harvested) before engraftment. It also provides a coating with human fibronectin, which initiates the process of graft adhesion into the recipient tissue and can carry fluorescent markers for the external control of the non-invasive cell position. In this work, we used a type of scaffold that allowed us to use the advantages of a scaffold-free cell suspension for cell delivery. Fragmented nanofibers (0.85 µm ± 0.18 µm in diameter) with fluorescent labels were used, with solitary cells seeded on them. Cell implantation experiments were performed in vivo. The proposed molecular vehicles made it possible to establish rapid (30 min) electromechanical contact between excitable grafts and the recipient heart. Excitable grafts were visualized with optical mapping on a rat heart with Langendorff perfusion at a 0.72 ± 0.32 Hz heart rate. Thus, the pre-restored grafts' excitability (with the help of a wrapped polymer scaffold) allowed rapid electromechanical coupling with the recipient tissue. This information could provide a basis for the reduction of engraftment arrhythmias in the first days after cell therapy.

Determination of glutathione in blood via capillary electrophoresis with pH-mediated stacking.

A new approach has been developed for the direct determination of reduced (glutathione [GSH]) and oxidized (glutathione disulfide [GSSG]) GSH in whole blood by means of capillary electrophoresis. Its features include GSH-stabilizing sample preparation, the use of an internal standard, and pH-mediated stacking. Blood stabilized with acid citrate and K3 EDTA was treated with acetonitrile with N-ethylmaleimide, and then the analytes were extracted with diethyl ether. The total analysis time was 8 min using a 50-µm (i.d.) by 32.5-cm (eff. length) silica capillary. The background electrolyte was 0.075-M citrate Na pH 5.8 with 200-µM cetyltrimethylammonium bromide and 5-µM sodium dodecyl sulfate, and the separation voltage was -14 kV. The quantification limit (S/N = 15) of the method was 1.5 µM for GSSG. The accuracy levels of GSH and GSSG analysis were 104% and 103%, respectively, and between-run precision levels were 2.6% and 3.2%, respectively. Analysis of blood samples from healthy volunteers (N = 24) showed that the levels of GSH and GSSG and the GSH/GSSG ratio in the whole blood were 1.05 ± 0.14 mM, 3.9 ± 1.25 µM, and 256 ± 94, respectively. Thus, the presented approach can be used in clinical and laboratory practice.

The Brønsted-Evans-Polanyi relationship in oxygen exchange of fuel cell cathode material SrCo0.9Ta0.1O3-δ with the gas phase.

Perovskite related oxides ABO3-δ exhibiting mixed ionic-electronic conductivity (MIEC) possess large deviations from the oxygen stoichiometry. When providing excellent application potential, this feature also makes it very difficult to study the reaction mechanism between such oxides and molecular oxygen, also known as the oxygen reduction reaction. The complexity of the theoretical interpretation of kinetic experiments originates from the significant dependence of the kinetic and equilibrium properties of MIEC oxides on δ. It is proposed to consider such grossly nonstoichiometric oxides having different oxygen nonstoichiometry as chemical homologues participating in the oxygen exchange reaction and forming a series continuous in δ. The continuous homologous series approach is considered using the example of SrCo0.9Ta0.1O3-δ, an SOFC cathode material. The equilibrium and kinetic properties of the oxide were studied by new methods of oxygen partial pressure relaxation and oxygen release. Linear free-energy relationships have been discovered in the homologous series: thermodynamic and kinetic enthalpy-entropy compensations, as well as the Brønsted-Evans-Polanyi relation. A relationship has been established between the change in the observed LFERs and the morphotropic phase transition in the oxide.

Laser intensity-dependent nonlinear-optical effects in organic whispering gallery mode cavity microstructures.

Nonlinear microresonators are very desired for a wide variety of applications. Up-conversion processes responsible for the transformation of IR laser radiation into visible are intensity-dependent and thus rather sensitive to all involved effects, which can mask each other. In this work we study the phenomena that are the most important for possible lasing in 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4 H-pyran dye spherical microresonators: the two-photon absorption and photobleaching. Based on the suggested model of the threshold-like dependence of the two-photon luminescence (TPL) on pump power, we demonstrate the role of intensity-dependent photobleaching in the appearance of the TPL and find a good agreement with the experiment. This finding is important for the analysis of lasing in nonlinear dye-based resonators.

Transformation of diamond to fullerene-type onions at pressure 70 GPa and temperature 2400 K.

We report the observation of a phase transition of diamond to denser than diamond carbon phase composed from 2 to 3 fullerene-type shells of onions. Raman spectra indicate the fullerene-type of the onions shells. The onions phase is a stable phase in a diamond instability zone of a phase diagram of carbon at pressure 70 GPa and temperature 2400 K. A mixture of diamond and Ni powders was heated by a laser beam under pressure in a diamond anvil cell. Both direct and catalytic diamond to onions transitions were observed during heating. The catalytic transformation includes the following steps. Melting of Ni during the laser heating at pressure 70 GPa, a 'diamond solution' (a transfer of carbon atoms from diamond) in liquid Ni and the formation of an equilibrium carbon phase from the supersaturated solution upon cooling. The catalytic process is a reverse one relative to the catalytic synthesis of diamond in a diamond stability zone at pressure around 6 GPa. The main result of our study is the presence of fullerene-type structures in the phase diagram of carbon in the region of diamond instability under high sub-Mbar pressure and wide range of temperatures.

Phase diagram of carbon and the factors limiting the quantity and size of natural diamonds.

Phase diagrams of carbon, and those focusing on the graphite-to-diamond transitional conditions in particular, are of great interest for fundamental and applied research. The present study introduces a number of experiments carried out to convert graphite under high-pressure conditions, showing a formation of stable phase of fullerene-type onions cross-linked by sp3-bonds in the 55-115 GPa pressure range instead of diamonds formation (even at temperature 2000-3000 K) and the already formed diamonds turn into carbon onions. Our results refute the widespread idea that diamonds can form at any pressure from 2.2 to 1000 GPa. The phase diagram built within this study allows us not only to explain the existing numerous experimental data on the formation of diamond from graphite, but also to make assumptions about the conditions of its growth in Earth's crust.

Visceral fat is associated with brain structure independent of human immunodeficiency virus infection status.

The combined effects of human immunodeficiency virus (HIV), obesity, and elevated visceral adipose tissue (VAT) on brain structure are unknown. In a cross-sectional analysis of Multicenter AIDS Cohort Study (MACS) participants, we determined associations between HIV serostatus, adiposity, and brain structure. Men (133 HIV+, 84 HIV-) in the MACS Cardiovascular 2 and magnetic resonance imaging (MRI) sub-studies with CT-quantified VAT and whole brain MRI measured within 1 year were assessed. Voxel-based morphometry analyzed brain volumes. Men were stratified by elevated (eVAT, ≥100cm2) or "normal" (nVAT, <100cm2) VAT. Forward stepwise modeling determined associations between clinical and demographic variables and regional brain volumes. eVAT was present in 67% of men. Groups were similar in age and education, but eVAT men were more likely to be HIV+ and have hypertension, diabetes mellitus, body mass index >25 kg/m2, smaller gray and white matter volumes, and larger cerebrospinal fluid volume than nVAT men. In multivariate analysis, hypertension, higher adiponectin, higher interleukin-6, age, diabetes mellitus, higher body mass index, and eVAT were associated with brain atrophy (p < 0.05, ordered by increasing strength of association), but HIV serostatus and related factors were generally not. No interactions were observed. Greater VAT was associated with smaller bilateral posterior hippocampus and left mesial temporal lobe and temporal stem white matter volume. Traditional risk factors are more strongly associated with brain atrophy than HIV serostatus, with VAT having the strongest association. However, HIV+ MACS men had disproportionately greater VAT, suggesting the risk for central nervous system effects may be amplified in this population.

Inflammatory Hematological Ratios in Adolescents with Mental Disorders: A Scoping Review.

BACKGOUND: Inflammatory hematological ratios (IHRs), such as neutrophil to lymphocyte, monocyte to lymphocyte, and platelet to lymphocyte ratios, are associated with mental disorders, symptoms severity, and the disease phase. Evidence from the studies in adult patients has been summarized in systematic reviews and meta-analyses. The results of the studies in adolescents remain poorly systematized. AIM: To summarize the findings from the studies that investigated the relationship of IHRs with mental disorders in adolescent patients. METHODS: This scoping review included studies of IHRs in patients aged 10-19 years with mental disorders (other than anorexia nervosa), published in English by December 31, 2023. The search for relevant papers was performed in MEDLINE. The studies were categorized into two groups: studies with external controls (healthy adolescents) and studies with internal controls (patients in different phases of mental disorder, with or without self-harm/suicidal behaviors). RESULTS: A total of 11 studies were included in the review (all cross-sectional ones). The results of these studies demonstrate that 1) adolescents with mental disorders (major depressive disorder, psychotic disorders, obsessive-compulsive disorder, attention deficit hyperactivity disorder, substance use disorders) have higher IHR values than individuals of the same age without corresponding disorders (5 studies); 2) IHR values are positively correlated with the severity of psychopathological symptoms (1 study); 3) higher IHR values are associated with the phase of the mental disorder - manic episode in bipolar disorder (1 study) and exacerbation of psychosis in psychotic disorders (1 study); and 4) higher IHR values are associated with self-harm/suicidal behaviors - suicide attempts (1 study) and non-suicidal self-injury (1 study). CONCLUSION: IHRs are associated with mental disorders in adolescents, and higher IHR values are associated with a more severe/acute clinical presentation (severity of symptoms, mania, acute psychosis, self-harm/suicidal behaviors). Further studies of higher methodological quality are needed to evaluate the diagnostic and prognostic value of IHRs as biomarkers of mental disorders in adolescence.

Significance of Mitochondrial Dysfunction in the Pathogenesis of Parkinson's Disease.

Parkinson's disease (PD) is characterized by the degeneration of the dopaminergic neurons of the corpus striatum, which can be caused by the disruption of processes of mitochondrial homeostasis, including mitophagy, mitochondrial fusion and division, mitochondrial transport, accumulation of reactive oxygen species (ROS), and calcium signaling. Dopaminergic neurons are particularly vulnerable to mitochondrial dysfunction due to their polarized and expanded structure and high bioenergy needs. The molecular basis of these disorders is manifested in mutations of mitochondrial homeostasis proteins. Understanding the functions of these proteins and the disorders caused by these mutations can be used to create therapeutics for the treatment of PD and diagnostic biomarkers of PD. A comprehensive analysis of research papers to identify promising therapeutic targets and drug compounds that target them, as well as biomarkers of mitochondrial dysfunction that can be used in clinical practice for the treatment of PD has been conducted in the current review. This practical approach advantageously emphasizes the difference between this work and other reviews on similar topics. The selection of articles in this review was carried out using the following keyword searches in scientific databases: PubMed, Google Scholar, NSBI, and Cochrane. Next, the most relevant and promising studies were re-selected.

Cholesteryl Ester Transfer Protein (CETP) Variations in Relation to Lipid Profiles and Cardiovascular Diseases: An Update.

Lipid metabolism plays an essential role in the pathogenesis of cardiovascular and metabolic diseases. Cholesteryl ester transfer protein (CETP) is a crucial glycoprotein involved in lipid metabolism by transferring cholesteryl esters (CE) and triglycerides (TG) between plasma lipoproteins. CETP activity results in reduced HDL-C and increased VLDL- and LDL-C concentrations, thus increasing the risk of cardiovascular and metabolic diseases. In this review, we discuss the structure of CETP and its mechanism of action. Furthermore, we focus on recent experiments on animal CETP-expressing models, deciphering the regulation and functions of CETP in various genetic backgrounds and interaction with different external factors. Finally, we discuss recent publications revealing the association of CETP single nucleotide polymorphisms (SNPs) with the risk of cardiovascular and metabolic diseases, lifestyle factors, diet and therapeutic interventions. While CETP SNPs can be used as effective diagnostic markers, diet, lifestyle, gender and ethnic specificity should also be considered for effective treatment.

Coronary atherosclerotic plaque regression strategies.

Atherosclerosis poses a significant and widespread problem at the population level. Consequently, there is a pressing need to develop effective methods to reduce the risk associated with this condition, which holds a prominent position in cardiology research. The primary manifestation of atherosclerosis involves plaque formation on the walls of coronary arteries. These plaques not only disrupt blood flow but also raise the likelihood of thrombosis and subsequent cardiovascular events. Unfortunately, atherosclerosis itself is usually asymptomatic, resulting in challenges with diagnosis and a delayed initiation of treatment. Hence, strategies focusing on the regression of existing plaques within blood vessels play a crucial role. The present review encompasses comprehensive data on the regression of coronary atherosclerotic plaques, examining both the underlying mechanisms and a range of regression strategies, encompassing lifestyle modifications to medical interventions.

Atherosclerosis originating from childhood: Specific features.

Atherosclerosis is extremely widespread. Traditionally, it is considered a disease of older people, who most often experience problems with the heart and blood vessels. While much attention from the scientific community has been paid to studying the association between aging and atherosclerosis, as well as its consequences, there is evidence that atherosclerosis occurs at an early age. Atherosclerosis may form both during intrauterine development and in childhood. Nutrition plays an important role in childhood atherosclerosis, along with previous infectious diseases and excess weight of both the child and the mother. In the present review, we examined the development of atherosclerosis and the prerequisites in childhood.

Non-rodent Models of Atherosclerosis: Repurposing of Existing Drugs and Search for Novel Treatment Strategies.

Atherosclerosis and associated cardiovascular diseases are the leading causes of illness and mortality worldwide. The development of atherosclerosis is a complex process involving oxidative stress, surplus lipid deposition and retention, endothelial dysfunction, and chronic inflammation. Developing novel anti-atherogenic and repurposing existing drugs requires the use of suitable animal models to characterise the fundamental mechanisms underlying atherosclerosis initiation and progression and to evaluate potential therapeutic effects. Commonly used rodent models, however, are not always appropriate, and other models may be required to translate these discoveries into valuable preventive and treatment agents for human applications. Recent advances in gene-editing tools for large animals have allowed the creation of animals that develop atherosclerosis faster and more similarly to humans in terms of lesion localisation and histopathology. In this review, we discuss the major advantages and drawbacks of the main non-rodent animal models of atherosclerosis, particularly rabbits, pigs, zebrafish, and non-human primates. Moreover, we review the application of recently invented novel therapeutic methods and agents, and repurposed existing drugs (such as antidiabetic and anticancer) for atherosclerosis treatment, the efficacy of which is verified on non-rodent animal models of atherosclerosis. In total, the proper selection of a suitable animal model of atherosclerosis facilitates reproducible and rigorous translational research in repurposing of existing drugs, discovering new therapeutic strategies, and validating novel anti-atherosclerotic drugs.

Analysis of Mutational Burden of Mitochondrial Genome in Cells of Different Human Organs and Tissues.

BACKGROUND: Cells of different human organs and tissues contain different numbers of mitochondria. In these organelles, there are different copies of the mitochondrial genome, which is characteristic of a certain organ or tissue. OBJECTIVE: The aim of the investigation was to analyze the results of scientific works dedicated to the analysis of heteroplasmy levels of mitochondrial genome mutations in a number of organs and tissues. METHODS: Based on literature data, the level of heteroplasmy of mitochondrial genome mutations was analyzed in organs such as the liver, lungs, muscles, small intestine, large intestine, spleen, kidney, brain, heart, and hair. In addition, this parameter was studied in such tissues as leukocytes, buccal epithelium, and epithelial cells from urine. RESULTS: Significant differences in the mutational burden of the mitochondrial genome were found in various samples of organs and tissues. The highest heteroplasmy level for mtDNA mutations was in muscles; it was lower in buccal epithelium; and in human blood cells, the heteroplasmy level of mitochondrial mutations turned out to be significantly lower compared to other tissues. During the comparison of samples of patients with different diseases and healthy people, significant differences were found in the heteroplasmy level between some organs and tissues. CONCLUSION: The heteroplasmy level of mitochondrial genome mutations can significantly differ in the organs and tissues of individuals. In addition, in a number of literature sources, it is noted that there is a dependence on the mutational burden of the mitochondrial genome from the type of disease, sex, and age of a person.