Mechanisms of Candida Resistance to Antimycotics and Promising Ways to Overcome It: The Role of Probiotics

Probiotics and Antimicrobial Proteins - Pathogenic Candida and infections caused by those species are now considered as a serious threat to public health. The treatment of candidiasis is...     

Exosomes from neuronal stem cells may protect the heart from ischaemia/reperfusion injury via JAK1/2 and gp130

Myocardial infarction requires urgent reperfusion to salvage viable heart tissue. However, reperfusion increases infarct size further by promoting mitochondrial damage in cardiomyocytes. Exosomes from a wide range of different cell sources have been shown to activate cardioprotective pathways in cardiomyocytes, thereby reducing infarct size. Yet, it is currently challenging to obtain highly pure exosomes in quantities enough for clinical studies. To overcome this problem, we used exosomes isolated from CTX0E03 neuronal stem cells, which are genetically stable, conditionally inducible and can be produced on an industrial scale. However, it is unknown whether exosomes from neuronal stem cells may reduce cardiac ischaemia/reperfusion injury. In this study, we demonstrate that exosomes from differentiating CTX0E03 cells can reduce infarct size in mice. In an in vitro assay, these exosomes delayed cardiomyocyte mitochondrial permeability transition pore opening, which is responsible for cardiomyocyte death after reperfusion. The mechanism of MPTP inhibition was via gp130 signalling and the downstream JAK/STAT pathway. Our results support previous findings that exosomes from non-cardiomyocyte-related cells produce exosomes capable of protecting cardiomyocytes from myocardial infarction. We anticipate our findings may encourage scientists to use exosomes obtained from reproducible clinical-grade stocks of cells for their ischaemia/reperfusion studies.     

Climatic Factors Influencing the Anthrax Outbreak of 2016 in Siberia,Russia

In 2016, an outbreak of anthrax killing thousands of reindeer and affecting dozens of humans occurred on the Yamal peninsula, Northwest Siberia, after 70 years of epidemiological situation without outbreaks. The trigger of the outbreak has been ascribed to the activation of spores due to permafrost thaw that was accelerated during the summer heat wave. The focus of our study is on the dynamics of local environmental factors in connection with the observed anthrax revival. We show that permafrost was thawing rapidly for already 6 years before the outbreak. During 2011–2016, relatively warm years were followed by cold years with a thick snow cover, preventing freezing of the soil. Furthermore, the spread of anthrax was likely intensified by an extremely dry summer of 2016. Concurrent with the long-term decreasing trend in the regional annual precipitation, the rainfall in July 2016 was less than 10% of its 30-year mean value. We conclude that epidemiological situation of anthrax in the previously contaminated Arctic regions requires monitoring of climatic factors such as warming and precipitation extremes.

     

New method of FACS analyzing and sorting of intact whole ovarian fragments (COPAS) after long time (24 h) cooling to 5 °C before cryopreservation

As recently announced by the American Society for Reproductive Medicine (ASRM), human ovarian tissue cryopreservation is an established option for fertility preservation in prepubertal girls and young women undergoing gonadotoxic treatments for cancer as well as some autoimmune diseases. Proper ovarian tissue assessment before and after cryopreservation is essential to increase success rates. Ovarian fragments from 16 patients were divided into small pieces in form of cortex with medulla, and randomly divided into the following two groups. Pieces of Group 1 (n?=?16) were frozen immediately after operation, thawed and just after thawing their quality was analyzed. Group 2 pieces (n?=?16) after operation were cooled to 5 °C for 24 h, then frozen after 24 h pre-cooling to 5 °C, thawed and just after thawing their quality was analyzed. The effectiveness of the pre-freezing cooling of tissue was evaluated by the development and viability of follicles (Calcein-AM and Propidium Iodide) using complex object parametric analyzer and sorter machine (COPAS). Positive effect of cooling of cells to low supra-zero temperatures on their future development after re-warming has been observed. New flow cytometry- technique is suitable for the evaluation and sorting of cryopreserved whole human whole intact ovarian fragments. Long time (24 h) cooling of ovarian tissue to 5 °C before cryopreservation has a trend of a cell viability increasing.

     

Oxidation-induced calcium-dependent dehydration of normal human red blood cells

Phenazine-methosulphate (PMS) is a strong oxidant that induces reactive oxygen species (ROS) formation in cells. Though it has been shown that PMS increases the red blood cell (RBC) membrane permeability to K⁺, the hypotheses on the mechanism of PMS-induced effects are contradictory and there are no data on volume changes induced by this oxidant. Therefore, the influence of the PMS + ascorbate oxidative system on the volume of normal human RBCs was studied. In a Ca^{2 +} -containing medium, PMS + ascorbate caused dehydration (shrinking) of RBCs judged by: (1) changes in the density and osmotic resistance distributions of RBCs, and (2) a decrease in their low-angle scattering assessed by FACS analysis. The dehydration resulted from activation of the Gardos channels, was PMS and ascorbate concentration-dependent, was associated with broadening of the density and osmotic resistance distributions of the RBCs, and decreased in the presence of the taxifolin and rutin antioxidants. These findings contribute to a better understanding of the physiology and pathology of oxidatively-modified RBCs and may be of practical significance in estimating the antioxidant activity of various substances.     

Peptide Mimetic of the S100A4 Protein Modulates Peripheral Nerve Regeneration and Attenuates the Progression of Neuropathy in Myelin Protein P0 Null Mice

We recently found that S100A4, a member of the multifunctional S100 protein family, protects neurons in the injured brain and identified two sequence motifs in S100A4 mediating its neurotrophic effect. Synthetic peptides encompassing these motifs stimulated neuritogenesis and survival in vitro and mimicked the S100A4-induced neuroprotection in brain trauma. Here, we investigated a possible function of S100A4 and its mimetics in the pathologies of the peripheral nervous system (PNS). We found that S100A4 was expressed in the injured PNS and that its peptide mimetic (H3) affected the regeneration and survival of myelinated axons. H3 accelerated electrophysiological, behavioral and morphological recovery after sciatic nerve crush while transiently delaying regeneration after sciatic nerve transection and repair. On the basis of the finding that both S100A4 and H3 increased neurite branching in vitro, these effects were attributed to the modulatory effect of H3 on initial axonal sprouting. In contrast to the modest effect of H3 on the time course of regeneration, H3 had a long-term neuroprotective effect in the myelin protein P₀ null mice, a model of dysmyelinating neuropathy (Charcot-Marie-Tooth type 1 disease), where the peptide attenuated the deterioration of nerve conduction, demyelination and axonal loss. From these results, S100A4 mimetics emerge as a possible means to enhance axonal sprouting and survival, especially in the context of demyelinating neuropathies with secondary axonal loss, such as Charcot-Marie-Tooth type 1 disease. Moreover, our data suggest that S100A4 is a neuroprotectant in PNS and that other S100 proteins, sharing high homology in the H3 motif, may have important functions in PNS pathologies.     

Synthesis and DNA Duplex Stabilities of Oligonucleotides Containing C-5-(3-Methoxypropynyl)-2′-deoxyuridine Residues

Abstract

5′-Dimethoxytrityl-5-(3-methoxypropynyl)-2′-deoxyuridine phosphoroamidite was synthesized with the use of commercial 3- methoxypropyne. Oligonucleotides (ODNs) containing 5-(3- ethoxypropynyl)- 2′-deoxyuridine in different positions were prepared. The stabilities of the duplexes formed by these ODNs with the complementary templates are increased in comparison with the unmodified counterparts. On average modified residue incorporated, the Tm is raised by 1°C.     

Reagents For The Selective Immobilization Of Oligonucleotides On Solid Supports

New reagents (CPGs and phosphoramidites) for automatic solid phase synthesis of modified oligonucleotides were designed. Three oligonucleotides carrying fluorescent label at the 5′-terminus and an anchor group at the 3′-terminus were prepared and their immobilization in orthogonal conditions on solid supports was studied.     

Synthesis and Application of Negatively Charged PNA Analogues

Negatively charged DNA mimics containing phosphonate analogues of peptide nucleic acids were designed, and their physicochemical and biological properties were evaluated in the comparison with natural oligonucleotides, classical peptide nucleic acids, and morpholino phosphorodiamidate oligonucleotide analogues. The results obtained revealed a high potential of phosphonate-containing PNA derivatives for a number of biological applications, such as diagnostic, nucleic acids analysis, and inhibition of gene expression.