DNA Repair Polymorphisms in B-cell Chronic Lymphocytic Leukemia in Sufferers of Chernobyl Nuclear Power Plant Accident

An association between DNA repair gene polymorphisms, environmental factors, and development of some types of cancer has been suggested by several studies. Chronic lymphocytic leukemia (CLL) is the most common form of leukemia in the clean-up workers of the Chernobyl Nuclear Power Plant (NPP) accident and it has some specific features. Therefore, we have studied the possible differences in DNA repair gene polymorphisms in CLL patients depending on ionizing radiation (IR) exposure history and their clinical characterictics. Arg399Gln XRCC1, Thr241Met XRCC3, and Lys751Gln XPD polymorphisms were studied in 64 CLL patients, exposed to IR due to the Chernobyl NPP accident, 114 IR-non-exposed CLL patients, and 103 sex- and age-matched IR-exposed controls using polymerase chain reaction-restriction fragment-length polymorphism analysis. All investigated polymorphisms were equally distributed between two groups of CLL patients and IR-exposed controls, except that that there was a significant reduction of the common homozygous Lys/Lys XPD genotype among IR-exposed CLL patients (23.7%) compared with IR-exposed controls (45.6%), OR = 0.37; 95% CI = 0.18-0.75; (P = 0.005). The number of IR-non-exposed CLL patients (37.4%) with the Lys/Lys XPD genotype was also decreased compared to IR-exposed controls, although this difference was not significant (P = 0.223). These preliminary data suggest a possible modifying role of Lys751Gln XPD polymorphism for the development of CLL, expecially in radiation-exposed persons.     

Broad-spectrum anti-tumor and anti-metastatic DNA vaccine based on p62-encoding vector

Autophagy plays an important role in neoplastic transformation of cells and in resistance of cancer cells to radio- and chemotherapy. p62 (SQSTM1) is a key component of autophagic machinery which is also involved in signal transduction. Although recent empirical observations demonstrated that p62 is overexpressed in variety of human tumors, a mechanism of p62 overexpression is not known. Here we report that the transformation of normal human mammary epithelial cells with diverse oncogenes (RAS, PIK3CA and Her2) causes marked accumulation of p62. Based on this result, we hypothesized that p62 may be a feasible candidate to be an anti-cancer DNA vaccine. Here we performed a preclinical study of a novel DNA vaccine encoding p62. Intramuscularly administered p62-encoding plasmid induced anti-p62 antibodies and exhibited strong antitumor activity in four models of allogeneic mouse tumors – B16 melanoma, Lewis lung carcinoma (LLC), S37 sarcoma, and Ca755 breast carcinoma. In mice challenged with Ca755 cells, p62 treatment had dual effect: inhibited tumor growth in some mice and prolonged life in those mice which developed tumor size similar to control. P62-encoding plasmid has demonstrated its potency both as a preventive and therapeutic vaccine. Importantly, p62 vaccination drastically suppressed metastasis formation: in B16 melanoma where tumor cells where injected intravenously, and in LLC and S37 sarcoma with spontaneous metastasis. Overall, we conclude that a p62-encoding vector(s) constitute(s) a novel, effective broad-spectrum antitumor and anti-metastatic vaccine feasible for further development and clinical trials.     

Grain boundary formation through particle detachment during coarsening of nanoporous metals

Grain boundary formation during coarsening of nanoporous gold (NPG) is investigated wherein a nanocrystalline structure can form by particles detaching and reattaching to the structure. MicroLaue and electron backscatter diffraction measurements demonstrate that an in-grain orientation spread develops as NPG is coarsened. The volume fraction of the NPG sample is near the limit of bicontinuity, at which simulations predict that a bicontinuous structure begins to fragment into independent particles during coarsening. Phase-field simulations of coarsening using a computationally generated structure with a volume fraction near the limit of bicontinuity are used to model particle detachment rates. This model is tested by using the measured NPG structure as an initial condition in the phase-field simulations. We predict that up to ∼5% of the NPG structure detaches as a dealloyed Ag75Au25 sample is annealed at 300 °C for 420 min. The quantity of volume detached is found to be highly dependent on the volume fraction and volume fraction homogeneity of the nanostructure. As the void phase in the experiments cannot support independent particles, they must fall and reattach to the structure, a process that results in the formation of new grain boundaries. This particle reattachment process, along with other classic processes, leads to the formation of grain boundaries during coarsening in nanoporous metals. The formation of grain boundaries can impact a variety of applications, including mechanical strengthening; thus, the consideration and understanding of particle detachment phenomena are essential when studying nanoporous metals.

Nanoporous metals are prototypical bicontinuous structures with a network of pores and ligaments. They are created by a number of metallic dealloying processes (1–6) allowing nearly any bulk metal to be transformed into a bicontinuous two-phase mixture of metal and void phase (7). These metals have a large interfacial area per volume enabling exciting applications in oxygen reduction (8), electromechanical devices (9), battery electrodes (10), actuators (11), and catalysts (12). Given the large surface area per volume, nanoporous structures frequently undergo coarsening when annealed at elevated temperatures. Nanoporous metals coarsen by surface diffusion (13–15), a process where the characteristic length, L, increases in time, t, according to the power law L∼t1/4 (16). Coarsening decreases the total interfacial energy of the structure, which greatly affects its material properties. For instance, coarsening is used to select the length scale in the structure, which alters the sizes of pores and ligaments (7, 17–20), ultimately impacting optical, chemical, and mechanical properties (21, 22), such as the elastic modulus (23). Nanoporous gold (NPG) often serves as a prototype for studying nanoporous metals (7). This paper investigates grain boundary formation as NPG coarsens and shows that the formation of a significant number of these boundaries is from particle detachment and subsequent reattachment.Metallic samples prior to dealloying have grain sizes on the order of 10 to 100 μm (24). Dealloying and annealing of bulk nanoporous metals are typically believed to preserve the grain orientation of the original metallic sample. This was demonstrated through electron backscatter diffraction (EBSD) measurements (1) and scanning electron microscopy (SEM) images (25) for NPG. However, these techniques provide information only about the external surfaces, not the bulk structure. The formation of an in-grain orientation spread would demonstrate that nanoporous metals can develop nanocrystallinity. Some recent work has observed a developed nanocrystalline structure in nanoporous metallic samples after dealloying and annealing. Sun et al. (26) observed grain boundary formation during annealing of NPG but assumed that the varying orientations formed due to the small grain size in the original alloy. High-resolution transmission electron microscopy (HRTEM) (27) and X-ray diffraction (28) were used to identify a nanocrystalline structure in NPG postdealloying. Nanocrystalline structures have also been identified in nanoporous platinum (29) and copper (30) postdealloying. Theories of how these grain boundaries form during dealloying and annealing have not been fully investigated. Dealloyed NPG samples have been shown to contain lattice dislocations (24). It is possible that there are driving forces for dislocations to form low-angle grain boundaries in the structure when coarsening at elevated temperatures.Coarsening of nanoporous metals is often compared to simulations that coarsen computationally generated (CG) bicontinuous structures, e.g., those formed in simulations of spinodal decomposition (31). Evolution of these structures has been studied with phase-field (31–35) and kinetic Monte Carlo (KMC) (36–38) methods. In certain volume fraction ranges, particle detachment is observed during simulations of coarsening, altering the topology of the structure. This breaking of ligaments in the structure is due to a Rayleigh–Plateau instability (38), the same mechanism causing ligament pinch-off (a ligament breaking in one place) during coarsening of nanoporous metals (13, 39, 40). The topology of an object in three dimensions (3D) is quantified by the Betti numbers: β0, the number of independent objects; β1, the number of handles (genus); and β2, the number of enclosed voids in the structure. Assuming no enclosed voids, the Euler characteristic of a 3D structure is given by χ=β0−β1 (41). When a particle detaches from the microstructure, β0 increases by 1. As particles detach from the end of ligaments, β1 remains the same. If a ligament breaks in one place (a process that is referred to as a ligament pinch-off), β1 decreases by 1 and β0 remains the same. Here we define particle detachment as the process of creating small (in size when compared to the main bicontinuous structure) isolated bodies.Simulations have demonstrated that the topology of a structure has a strong dependence on the minority phase volume fraction, ϕ, and can vary drastically within a small range of ϕ (34, 38). Using KMC, Li et al. (38) investigated coarsening via surface diffusion of structures initialized as leveled Gaussian random fields with ϕ of 22, 25, and 27% and increments of 5% from 30 to 50%. By investigating the topology, they found that structures with a ϕ lower than 30% are evolving toward a particle-dominated system, while structures with a ϕ higher than 40% are evolving as a fully connected system (β0=1). As the topological changes are related to how particles detach, we establish two regimes of topological evolution. In the particle-dominated regime (low ϕ), the structure evolves toward a state where the number of handles (β1) is either zero or low compared to the number of particles (β0). In the ligament-dominated regime (high ϕ), the structure evolves toward a state where there is a low number of particles (β0) compared to the number of handles (β1). In between these regimes (intermediate ϕ), the structure evolves to a state with an intermediate number of particles and handles, and any transition to the particle-dominated regime or the ligament-dominated regime occurs too slowly to be feasibly observed. We define this approximate boundary between regimes as the limit of bicontinuity, as the structure begins to break up while still maintaining a high degree of connectivity. Due to the approximate nature of this definition, a range of ϕ (e.g., 30 to 35%) may be considered to be “at” the limit of bicontinuity. We are most likely to observe particle detachment in structures with a ϕ at the limit of bicontinuity, where β0 might be stable or increasing throughout coarsening (signifying particle detachment) while a majority of the solid volume is contained in the main bicontinuous structure. Simulations with a ϕ in the range 30 to 35% have not yet been extensively studied despite the many coarsening experiments of nanoporous metals that are within this range.Experiments commonly study NPG samples with a ϕ between 25 and 36% postdealloying and report fully connected bicontinuous structures (17, 19, 20, 42–47). In this case, the minority phase volume fraction, ϕ, corresponds to the gold volume fraction. These ϕ values are just below or at the limit of bicontinuity predicted by simulation. However, the stability of the structures during coarsening is not always investigated, especially at lower ϕ. Detachment of particles from the bicontinuous structure can be kinetically inhibited due to short coarsening times or slow coarsening rates. However, experiments that coarsen NPG for sufficiently long times such that the mean ligament diameter increased by a factor of 16 have still reported fully connected bicontinuous structures (19, 20). The bicontinuity does not necessarily indicate that disconnections do not occur during the evolution; since the vapor phase cannot support independent particles, any particles that detach would presumably fall under their own weight and reattach elsewhere, leading to a fully connected bicontinuous structure and the formation of grain boundaries.As the ϕ of many NPG samples is at the limit of bicontinuity, we show that particles detach as NPG coarsens, and we hypothesize that the reattachment of particles leads to the formation of many of the grain boundaries that are observed in the microstructure. The results of microLaue and EBSD measurements of coarsened NPG samples with a ϕ at the limit of bicontinuity identify large in-grain orientation spreads that develop during coarsening. Phase-field simulations of coarsening of a CG bicontinuous structure with a ϕ at the limit of bicontinuity are conducted to investigate how particle detachment occurs in this regime. Subsequently, the morphology of the CG and NPG structures is characterized to search for evidence of particle reattachment phenomena. A coarsened NPG structure is then used as an initial condition in a phase-field simulation to observe how particle detachment would occur if the sample had continued to coarsen. These calculations that begin with the experimentally measured structure have identified the critical role of volume fraction homogeneity in particle detachment phenomena.     

Identification of Nordic Berries with Beneficial Effects on Cognitive Outcomes and Gut Microbiota in High-Fat-Fed Middle-Aged C57BL/6J Mice

High-fat diets are associated with neuronal and memory dysfunction. Berries may be useful in improving age-related memory deficits in humans, as well as in mice receiving high-fat diets. Emerging research has also demonstrated that brain health and cognitive function may be related to the dynamic changes in the gut microbiota. In this study, the impact of Nordic berries on the brain and the gut microbiota was investigated in middle-aged C57BL/6J mice. The mice were fed high-fat diets (60%E fat) supplemented with freeze-dried powder (6% dwb) of bilberry, lingonberry, cloudberry, blueberry, blackcurrant, and sea buckthorn for 4 months. The results suggest that supplementation with bilberry, blackcurrant, blueberry, lingonberry, and (to some extent) cloudberry has beneficial effects on spatial cognition, as seen by the enhanced performance following the T-maze alternation test, as well as a greater proportion of DCX-expressing cells with prolongation in hippocampus. Furthermore, the proportion of the mucosa-associated symbiotic bacteria Akkermansia muciniphila increased by 4–14 times in the cecal microbiota of mice fed diets supplemented with lingonberry, bilberry, sea buckthorn, and blueberry. These findings demonstrate the potential of Nordic berries to preserve memory and cognitive function, and to induce alterations of the gut microbiota composition.     

Inhibition of IK,ACh current may contribute to clinical efficacy of class I and class III antiarrhythmic drugs in patients with atrial fibrillation

Inward rectifier potassium currents I_K1 and acetylcholine activated I_K,ACh are implicated in atrial fibrillation (AF) pathophysiology. In chronic AF (cAF), I_K,ACh develops a receptor-independent, constitutively active component that together with increased I_K1 is considered to support maintenance of AF. Here, we tested whether class I (propafenone, flecainide) and class III (dofetilide, AVE0118) antiarrhythmic drugs inhibit atrial I_K1 and I_K,ACh in patients with and without cAF. I_K1 and I_K,ACh were measured with voltage clamp technique in atrial myocytes from 58 sinus rhythm (SR) and 35 cAF patients. The M-receptor agonist carbachol (CCh; 2 μM) was employed to activate I_K,ACh. In SR, basal current was not affected by either drug indicating no effect of these compounds on I_K1. In contrast, all tested drugs inhibited CCh-activated I_K,ACh in a concentration-dependent manner. In cAF, basal current was confirmed to be larger than in SR (at −80 mV, −15.2 ± 1.2 pA/pF, n = 88/35 vs. −6.5 ± 0.4 pA/pF, n = 194/58 [myocytes/patients]; P < 0.05), whereas CCh-activated I_K,ACh was smaller (−4.1 ± 0.5 pA/pF vs. −9.5 ± 0.6 pA/pF; P < 0.05). In cAF, receptor-independent constitutive I_K,ACh contributes to increased basal current, which was reduced by flecainide and AVE0118 only. This may be due to inhibition of constitutively active I_K,ACh channels. In cAF, all tested drugs reduced CCh-activated I_K,ACh. We conclude that in cAF, flecainide and AVE0118 reduce receptor-independent, constitutively active I_K,ACh, suggesting that they may block I_K,ACh channels, whereas propafenone and dofetilide likely inhibit M-receptors. The efficacy of flecainide to terminate AF may in part result from blockade of I_K,ACh.     

COVID-19 vaccinations and rates of infections,hospitalizations, ICU admissions,and deaths in Europe during SARS-CoV-2 Omicron wave in the first quarter of 2022

The vaccination campaigns brought hope to minimizing the coronavirus disease 2019 (COVID-19) burden. However, the emergence of novel, highly transmissible Omicron lineage of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the waning of neutralizing antibodies a few months after vaccination has brought concerns over the vaccine efficacy. The present work analyzed the relationships between COVID-19 vaccine coverage (completion of primary course and booster dose intake) in the European Economic Area and rates of infection, hospitalizations, admissions to intensive care units (ICU), and deaths during the Omicron wave in the first quarter of 2022 (January–April). As demonstrated, infection rates were not correlated to vaccine coverage in any considered month. For January and February, the rates of hospitalizations, intensive care unit (ICU) admissions, and death due to COVID-19 were strongly negatively correlated (r =− 0.54 to −0.82) with the percentage of individuals who completed initial vaccination protocol and the percentage of those who received a booster dose. However, in March and April, the percentage of the population with primary vaccination course correlated negatively only with ICU admissions (r = −0.77 and −0.46, respectively). The uptake of boosters in March still remained in significant negative correlation with hospitalizations (r = −0.45), ICU admissions (r = −0.70) and deaths due to COVID-19 (r = −0.37), although in April these relationships were no longer observed. The percentage of individuals with confirmed SARS-CoV-2 infection did not correlate with the pandemic indices for any considered month. The study indicates that COVID-19 vaccination, including booster administration, was beneficial in decreasing the overwhelming of healthcare systems during the Omicron wave, but novel vaccine strategies may be required in the long term to enhance the effectiveness and durability of vaccine-induced protection during future waves of SARS-CoV-2 infections.     

Synthesis and biological evaluation of substituted (thieno[2,3-d]pyrimidin-4-ylthio)carboxylic acids as inhibitors of human protein kinase CK2

A novel series of substituted (thieno[2,3-d]pyrimidin-4-ylthio)carboxylic acids has been synthesized and tested in vitro towards human protein kinase CK2. It was revealed that the most active compounds inhibiting CK2 are 3-{[5-(4-methylphenyl)thieno[2,3-d]pyrimidin-4-yl]thio}propanoic acid and 3-{[5-(4-ethoxyphenyl)thieno[2,3-d]pyrimidin-4-yl]thio}propanoic acid (IC₅₀ values are 0.1 μM and 0.125 μM, respectively). Structure-activity relationships of 28 tested thienopyrimidine derivatives have been studied and binding mode of this chemical class has been predicted. Evaluation of the inhibitors on seven protein kinases revealed considerable selectivity towards CK2.     

Study of Concrete under Combined Action of Aggressive Environment and Long-Term Loading

A significant part of reinforced concrete structures is subjected to intensive environmental impact during operation. This can cause local destruction and failure of buildings if obligatory measures are not taken to protect them from corrosion. This is especially true for industrial buildings, where the environment could be contaminated with aggressive products or waste. An important issue is the development of methods for calculating the load-bearing capacity and serviceability of reinforced concrete structures with corrosion damage. The main reason for this is the necessity to determine the durability and reliability of buildings and structures and the estimation of their safe operation time. As corrosion damages of concrete are a critical issue, more detailed experimental studies are needed. This paper presents experimental studies of concrete prisms under the simultaneous action of an aggressive environment and a constant level of compressive force. In total, 32 prisms under different loading conditions and in different aggressive medium were tested. Samples were divided in series, for which different load levels were chosen (0.25fck, 0.35fck, 0.45fck). Additionally, control samples in the air and immersed in water were tested. During the experiment, different parameters were monitored and recorded: decrease of cross-sectional size, the temperature and environmental humidity. Results of the study showed that destruction occurred due to the presence of corrosion damages of concrete and a reduction of the cross-sectional area. The stresses in the concrete at the destruction stage were less than the value of the prism strength by 10–12%. It was established that along the contour of the section, there is a partially degraded layer of concrete of 1.5–3.7 mm thickness, with corrosion microcracks and corrosion products. Additionally, experimental and theoretical diagrams of concrete with corrosion damages were obtained and compared. The ultimate deformations of concrete with corrosion damage, which correspond to the prismatic strength of concrete, in comparison with undamaged concrete were lower by 11–18%. Therefore, the concrete strength is decreased during exploitation under loading in an aggressive environment, which needs to be taken into account during calculations.     

Multimarker Responses of Zebrafish to the Effect of Ibuprofen and Gemfibrozil in Environmentally Relevant Concentrations

Pharmaceutical pollution of water bodies is among the top-notch environmental health risks all over the world. The aim of the present study was to investigate the effects of two common pharmaceuticals namely ibuprofen and gemfibrozil on zebrafish at environmentally relevant concentrations. In zebrafish liver, gemfibrozil caused a decrease in glutathione and glutathione transferase and an increase in catalase but had no effect on lipid peroxidation and protein carbonylation. Ibuprofen altered the antioxidant defense system, promoted protein carbonylation in zebrafish liver, and increased vitellogenin-like protein in the blood. Ibuprofen and particularly gemfibrozil induced lysosomes biogenesis. Lactate dehydrogenase in the blood was also found to be higher in the studied groups. Studied pharmaceuticals did not affect complex II of the electron respiratory chain. Ibuprofen affects zebrafish health status more profoundly than gemfibrozil. Our results showed that pharmaceuticals even in low, environmentally realistic concentrations, induced profound changes in the stress-responsive systems of zebrafish.