Mesenchymal Stem Cells Early Response to Low-Dose Ionizing Radiation.

Introduction: Mesenchymal stem cells (MSCs) are applied as the therapeutic agents, e.g., in the tumor radiation therapy.

Opposite Pathways of Cholinergic Mechanisms of Hypoxic Preconditioning in the Hippocampus: Participation of Nicotinic α7 Receptors and Their Association with the Baseline Level of Startle Prepulse Inhibition.

(1) Background. A one-time moderate hypobaric hypoxia (HBH) has a preconditioning effect whose neuronal mechanisms are not studied well. Previously, we found a stable correlation between the HBH efficiency and acoustic startle prepulse inhibition (PPI).

[Neurological status and structural changes in the tracheal lymphoid tissue in rats with different resistance to emotional stress of experimental hemorrhagic stroke].

Objective: To study neurological status and structural changes in the tracheal lymphoid tissue in rats with different resistance to emotional stress in experimental hemorrhagic stroke.

Material And Methods: Evaluation of neurological deficit on the Menzies scale and a histological study of structural features of tracheal lymphoid tissue were performed on days 1, 3 and 7 of experimental hemorrhagic stroke in 98 Wistar male rats with different resistance to emotional stress. Stroke simulation was preceded by animal testing to determine individual stress resistance.

Identification of different cell clusters in the endothelium of atherosclerotic vessels and determination of inter-cluster gradient of proliferative and inflammatory activity as new diagnostic markers.

To characterize atherogenesis functionally, we studied the functional heterogeneity of endotheliocytes in carotid vessels with atherosclerotic plaques and identified several distinct cell clusters. We measured the Ki-67 labeling index (Ki-67 LI), percentage of Bcl-2 cells (CP) and expression of CCL5, IL 6 and VCAM1 in each cell cluster. We also investigated how these indicators change when the plaque becomes unstable and how they affect the risk of adverse cerebrovascular events in patients.

Copy number variations of satellite III (1q12) and ribosomal repeats in health and schizophrenia.

Objective: Earlier we studied the copy number variations (CNVs) of ribosomal repeat (rDNA) and the satellite III fragment (1q12) (f-SatIII) in the cells of schizophrenia patients (SZ) and healthy controls (HC). In the present study we pursued two main objectives: (1) to confirm the increased rDNA and decreased f-SatIII content in the genomes of enlarged SZ and HC samples and (2) to compare the rDNA and f-SatIII content in the same DNA samples of SZ and HC individuals.

Methods: We determined the rDNA CN and f-SatIII content in the genomes of leukocytes of 1770 subjects [HC (N = 814) and SZ (N = 956)].

1Q12 Loci Movement in the Interphase Nucleus Under the Action of ROS Is an Important Component of the Mechanism That Determines Copy Number Variation of Satellite III (1q12) in Health and Schizophrenia.

Genome repeat cluster sizes can affect the chromatin spatial configuration and function. Low-dose ionizing radiation (IR) induces an adaptive response (AR) in human cells. AR includes the change in chromatin spatial configuration that is necessary to change the expression profile of the genome in response to stress.

Peculiarities in Synthesis of Proteins Implicated in Memory Reconsolidation and Induction of Amnesia.

The peculiarities of implication of NMDA glutamate receptors and protein synthesis into the mechanisms responsible for impairment of memory reconsolidation were studied in edible snails conditioned to food aversion. Injections of NMDA glutamate receptor antagonists or protein synthesis inhibitor prior to reminding with conditioned food stimulus provoked development of amnesia after different latent periods. NMDA glutamate receptor antagonists gradually weakened the aversive reactions to conditioned stimulus presented in parallel with reminder during 1 h.

Role of nitric oxide in psychostimulant-induced neurotoxicity.

In recent decades, consumption of psychostimulants has been significantly increased all over the world, while exact mechanisms of neurochemical effects of psychomotor stimulants remained unclear. It is assumed that the neuronal messenger nitric oxide (NO) may be involved in mechanisms of neurotoxicity evoked by psychomotor stimulants. However, possible participation of NO in various pathological states is supported mainly by indirect evidence because of its short half-life in tissues.

Copy Number Variation of Satellite III (1q12) in Patients With Schizophrenia.

It was shown that copy number variations (CNVs) of human satellite III (1q12) fragment (f-SatIII) reflects the human cells response to stress of different nature and intensity. Patients with schizophrenia (SZ) experience chronic stress. The major research question: What is the f-SatIII CNVs in human leukocyte as a function of SZ? Biotinylated pUC1.

Long-term memory consolidation or reconsolidation impairment induces amnesia with key characteristics that are similar to key learning characteristics.

According to a common perspective, amnesia is a passive consequence of memory consolidation or reconsolidation impairment. The results of our own study, as well as literature data, allowed us to offer an interpretation of amnesia. Amnesia is an active process whose key characteristics are similar to those of other long-term plastic rearrangements of the brain, including learning processes.

Click histochemistry for whole-mount staining of brain structures.

Labeling of the replicating DNA with synthetic thymidine analogs is commonly used for marking the dividing cells. However, until now this method has only been applied to histological sections. A growing number of current approaches for three-dimensional visualization of large tissue samples requires detection of dividing cells within whole organs.

Accumulation of Circulating Cell-Free CpG-Enriched Ribosomal DNA Fragments on the Background of High Endonuclease Activity of Blood Plasma in Schizophrenic Patients.

Introduction: Schizophrenia (SZ) increases the level of cell death, leading to an increase in the concentration of circulating cell-free DNA (cfDNA). Ribosomal DNA (rDNA) contains many unmethylated CpG motifs that stimulate TLR9-MyD88-NF-B signaling and the synthesis of proinflammatory cytokines. The number of rDNA copies in the genomes of SZ patients is increased; therefore, we expect that the concentration of cell-free rDNA in the plasma of the SZ patients also increases.

Copy Number Variation of Human Satellite III (1q12) With Aging.

Human satellite DNA is organized in long arrays in peri/centromeric heterochromatin. There is little information about satellite copy number variants (CNVs) in aging and replicative cell senescence (RS). Biotinylated pUC1.

Oxidized Cell-Free DNA Role in the Antioxidant Defense Mechanisms under Stress.

The present study focuses on the investigation of the oxidized cell-free DNA (cfDNA) properties in several experimental models, including cultured cerebellum cells, peripheral blood lymphocytes (PBL), plasma, and hippocampus under an acute and chronic unpredictable stress model in rats. Firstly, our study shows that Spectrum Green fluorescence-labeled oxidized cfDNA fragments were transferred into the cytoplasm of 80% of the cerebellum culture cells; meanwhile, the nonoxidized cfDNA fragments do not pass into the cells. Oxidized cfDNA stimulates the antioxidant mechanisms and induction of transcription factor NRF2 expression, followed by an activation of NRF2 signaling pathway genes-rise of and gene expression and consequently NRF2 protein synthesis.

Near-Infrared Genetically Encoded Positive Calcium Indicator Based on GAF-FP Bacterial Phytochrome.

A variety of genetically encoded calcium indicators are currently available for visualization of calcium dynamics in cultured cells and in vivo. Only one of them, called NIR-GECO1, exhibits fluorescence in the near-infrared region of the spectrum. NIR-GECO1 is engineered based on the near-infrared fluorescent protein mIFP derived from bacterial phytochromes.

Slowly Reducible Genetically Encoded Green Fluorescent Indicator for In Vivo and Ex Vivo Visualization of Hydrogen Peroxide.

Hydrogen peroxide (HO) plays an important role in modulating cell signaling and homeostasis in live organisms. The HyPer family of genetically encoded indicators allows the visualization of HO dynamics in live cells within a limited field of view. The visualization of HO within a whole organism with a single cell resolution would benefit from a slowly reducible fluorescent indicator that integrates the HO concentration over desired time scales.

Protein synthesis inhibitors induce both memory impairment and its recovery.

The involvement of protein synthesis in the mechanisms of conditioned food aversion memory impairment and recovery in grape snails was studied. It was found that protein synthesis inhibitor (cycloheximide) injections before a reminder by the conditioned stimulus (CS) caused amnesia development. Three days after amnesia induction, injections of cycloheximide or another protein synthesis inhibitor, anisomycin, combined with a reminder by four CSs resulted in memory retrieval, which was saved for 24 h.

The whither of bacteriophytochrome-based near-infrared fluorescent proteins: Insights from two-photon absorption spectroscopy.

We present one- and two-photon-absorption fluorescence spectroscopic analysis of biliverdin (BV) chromophore-based single-domain near-infrared fluorescent proteins (iRFPs). The results of these studies are used to estimate the internal electric fields acting on BV inside iRFPs and quantify the electric dipole properties of this chromophore, defining the red shift of excitation and emission spectra of BV-based iRFPs. The iRFP studied in this work is shown to fit well the global diagram of the red-shift tunability of currently available BV-based iRFPs as dictated by the quadratic Stark effect, suggesting the existence of the lower bound for the strongest red shifts attainable within this family of fluorescent proteins.

NTnC-like genetically encoded calcium indicator with a positive and enhanced response and fast kinetics.

The NTnC genetically encoded calcium indicator has an advantageous design because of its smaller size, GFP-like N- and C-terminal ends and two-fold reduced number of calcium binding sites compared with widely used indicators from the GCaMP family. However, NTnC has an inverted and modest calcium response and a low temporal resolution. By replacing the mNeonGreen fluorescent part in NTnC with EYFP, we engineered an NTnC-like indicator, referred to as YTnC, that had a positive and substantially improved calcium response and faster kinetics.

Cognitive Tagging of Neurons: CREMediated Genetic Labeling and Characterization of the Cells Involved in Learning and Memory.

In this study, we describe use of Cre-mediated recombination to obtain a permanent genetic labeling of the brain neuronal networks activated during a new experience in animals. This method utilizes bitransgenic Fos-Cre-eGFP mice in which a green fluorescent protein is expressed upon tamoxifen-induced Cre-recombination only in the cells where immediate early gene expression takes place due to the new experience. We used the classical fear conditioning model to show that microscopy of the eGFP protein in Fos-Cre-eGFP mice enables mapping of the neurons of the various brain regions that undergo Cre-recombination during acquisition of a new experience.

NMDA or 5-HT receptor antagonists impair memory reconsolidation and induce various types of amnesia.

Elucidation of amnesia mechanisms is one of the central problems in neuroscience with immense practical application. Previously, we found that conditioned food presentation combined with injection of a neurotransmitter receptor antagonist or protein synthesis inhibitor led to amnesia induction. In the present study, we investigated the time course and features of two amnesias: induced by impairment of memory reconsolidation using an NMDA glutamate receptor antagonist (MK-801) and a serotonin receptor antagonist (methiothepin, MET) on snails trained with food aversion conditioning.

Spatial geometry of stem cell proliferation in the adult hippocampus.

The modes of stem cell divisions (e.g., symmetric vs.

Genetically encoded calcium indicator with NTnC-like design and enhanced fluorescence contrast and kinetics.

Background: The recently developed genetically encoded calcium indicator (GECI), called NTnC, has a novel design with reduced size due to utilization of the troponin C (TnC) as a Ca-binding moiety inserted into the mNeonGreen fluorescent protein. NTnC binds two times less Ca ions while maintaining a higher fluorescence brightness at the basal level of Ca in neurons as compared with the calmodulin-based GECIs, such as GCaMPs. In spite of NTnC's high brightness, pH-stability, and high sensitivity to single action potentials, it has a limited fluorescence contrast (F/F) and slow Ca dissociation kinetics.