Usefulness of New Neutrophil-Related Hematologic Parameters in Patients with Myelodysplastic Syndrome.

Myelodysplastic syndromes (MDS) are common malignant disorders with a poor prognosis. It is necessary to search for new rapid diagnostic methods to detect MDS patients with cytogenetic changes. The aim of the study was to assess new hematological neutrophil- and monocyte- related parameters I then bone marrow of MDS patient with and without cytogenetic changes.

Boron Clusters as Enhancers of RNase H Activity in the Smart Strategy of Gene Silencing by Antisense Oligonucleotides.

Boron cluster-conjugated antisense oligonucleotides (B-ASOs) have already been developed as therapeutic agents with "two faces", namely as potential antisense inhibitors of gene expression and as boron carriers for boron neutron capture therapy (BNCT). The previously observed high antisense activity of some B-ASOs targeting the epidermal growth factor receptor (EGFR) could not be rationally assigned to the positioning of the boron cluster unit: 1,2-dicarba--dodecaborane (0), [(3,3'-Iron-1,2,1',2'-dicarbollide) (1-), FESAN], and dodecaborate (2-) in the ASO chain and its structure or charge. For further understanding of this observation, we performed systematic studies on the efficiency of RNase H against a series of B-ASOs models.

2-Selenouridine, a Modified Nucleoside of Bacterial tRNAs, Its Reactivity in the Presence of Oxidizing and Reducing Reagents.

The 5-substituted 2-selenouridines are natural components of the bacterial tRNA epitranscriptome. Because selenium-containing biomolecules are redox-active entities, the oxidation susceptibility of 2-selenouridine (Se2U) was studied in the presence of hydrogen peroxide under various conditions and compared with previously reported data for 2-thiouridine (S2U). It was found that Se2U is more susceptible to oxidation and converted in the first step to the corresponding diselenide (Se2U), an unstable intermediate that decomposes to uridine and selenium.

tRNA 2-Selenouridine Synthase (SelU): Elucidation of Substrate Specificity to Understand the Role of -Geranyl-tRNA in the Conversion of 2-Thio- into 2-Selenouridines in Bacterial tRNA.

The bacterial enzyme tRNA 2-selenouridine synthase (SelU) is responsible for the conversion of 5-substituted 2-thiouridine (R5S2U), present in the anticodon of some bacterial tRNAs, into 5-substituted 2-selenouridine (R5Se2U). We have already demonstrated using synthetic RNAs that transformation S2U→Se2U is a two-step process, in which the S2U-RNA is geranylated and the resulting geS2U-RNA is selenated. Currently, the question is how SelU recognizes its substrates and what the cellular pathway of R5S2U→R5Se2U conversion is in natural tRNA.

Escherichia coli tRNA 2-selenouridine synthase SelU selects its prenyl substrate to accomplish its enzymatic function.

Bacterial tRNA 2-selenouridine synthase (SelU) in vitro converts S2U-RNA to its selenium analog (Se2U-RNA) in a two-step process: (i) geranylation of S2U-RNA (with geranyl pyrophosphate, gePP), and (ii) selenation of the resulting geS2U-RNA (with the selenophosphate anion, SePO). Using an S2U-containing anticodon stem-loop fragment derived from tRNA (S2U-RNA) and recombinant SelU with an MBP tag, we found that only geranyl (C) pyrophosphate is the substrate for this enzyme, while other pyrophosphates such as isopentenyl (C), dimethylallyl (C), farnesyl (C) and geranylgeranyl (C) are not. Interestingly, methyl (C)- and C-, C-, and C-prenyl-containing S2U-RNAs (which were chemically obtained) underwent the selenation reaction promoted by SelU, although the Se2U-RNA product was obtained in decreasing yields in the following order: geranyl ≥ farnesyl > dimethylallyl ≫ methyl.

Synthesis and properties of the anticodon stem-loop of human mitochondrial tRNA containing the disease-related G or mG nucleosides at position 37.

A single point mutation (A4435G) in the human mitochondrial tRNA (hmt-tRNA) gene causes severe mitochondrial disorders associated with hypertension, type 2 diabetes and LHON. This mutation leads to the exchange of A in the anticodon loop of hmt-tRNA for G and 1-methylguanosine (mG). Here we present the first synthesis and structural/biophysical studies of the anticodon stem and loop of pathogenic hmt-tRNAs.

Neutrophil Maturation, Reactivity and Granularity Research Parameters to Characterize and Differentiate Convalescent Patients from Active SARS-CoV-2 Infection.

Studying the dynamics changes of neutrophils during innate immune response in coronavirus 2019 (COVID-19) can help understand the pathogenesis of this disease. The aim of the study was to assess the usefulness of new neutrophil activation parameters: Immature Granulocyte (IG), Neutrophil Reactivity Intensity (NEUT-RI), Neutrophil Granularity Intensity (NEUT-GI), and data relating to granularity, activity, and neutrophil volume (NE-WX, NE-WY, NE-WZ) available in hematology analyzers to distinguish convalescent patients from patients with active SARS-CoV-2 infection and healthy controls (HC). The study group consisted of 79 patients with a confirmed positive RT-PCR test for SARS-CoV2 infection, 71 convalescent patients, and 20 HC.

Composites of Nucleic Acids and Boron Clusters (CBH) as Functional Nanoparticles for Downregulation of EGFR Oncogene in Cancer Cells.

Epidermal growth factor receptor (EGFR) is one of the most promising molecular targets for anticancer therapy. We used boron clusters as a platform for generation of new materials. For this, functional DNA constructs conjugated with boron clusters (B-ASOs) were developed.

Usefulness of the New Hematological Parameter: Reactive Lymphocytes RE-LYMP with Flow Cytometry Markers of Inflammation in COVID-19.

Identification of patients with activation of the immune system which indicates the presence of infection is essential, especially in the times of the global coronavirus 2019 (COVID-19) pandemic. The aim of the present study was to evaluate the reactive lymphocytes (RE-LYMP) parameter in COVID-19 and to correlate it with activation lymphocytes markers by flow cytometry. The study group consisted of 40 patients: with COVID-19 infection ( = 20) and with others virus infections without COVID-19 (COVID-19(-) virus ( = 20)) and 20 healthy donors (HC).

Evaluation and comparison of the new Mindray BC-6200 hematology analyzer with ADVIA 2120i.

Background: The Mindray BC-6200 is a new automatic hematology analyzer that quantifies the parameters of blood morphology and leukocyte differential in five populations (5-Diff). The aim of the study was to evaluate the BC-6200 and compare it with the Siemens ADVIA 2120i analyzer.

Materials And Methods: The comparison between BC-6200 and ADVIA 2120i analyzers was performed using 390 whole blood samples collected on K EDTA.

Formation of an RNA Quadruplex-Duplex Hybrid in Living Cells between mRNA of the Epidermal Growth Factor Receptor (EGFR) and a G-Rich Antisense Oligoribonucleotide.

Antisense DNA oligonucleotides, short interfering RNAs (siRNAs), and CRISPR/Cas9 genetic tools are the most useful therapeutic nucleic acids regulating gene expression based on the antisense specificity towards messenger RNA. Here, we present an effective novel strategy for inhibiting translation based on the antisense-controlled formation of an RNA quadruplex-duplex hybrid (QDH) between a G-rich RNA antisense oligoribonucleotide (Q-ASO) and specific mRNA, comprising two distant G-tracts. We selected epidermal growth factor receptor (EGFR) as a well-established target protein in anticancer therapy.

Different Oxidation Pathways of 2-Selenouracil and 2-Thiouracil, Natural Components of Transfer RNA.

Sulfur- and selenium-modified uridines present in the wobble position of transfer RNAs (tRNAs) play an important role in the precise reading of genetic information and tuning of protein biosynthesis in all three domains of life. Both sulfur and selenium chalcogens functionally operate as key elements of biological molecules involved in the protection of cells against oxidative damage. In this work, 2-thiouracil (S2Ura) and 2-selenouracil (Se2Ura) were treated with hydrogen peroxide at 1:0.

Metallacarborane Complex Boosts the Rate of DNA Oligonucleotide Hydrolysis in the Reaction Catalyzed by Snake Venom Phosphodiesterase.

Antisense oligonucleotides conjugated with boron clusters (B-ASOs) have been described as potential gene expression inhibitors and carriers of boron for boron neutron capture therapy (BNCT), providing a dual-action therapeutic platform. In this study, we tested the nucleolytic stability of DNA oligonucleotides labeled with metallacarborane [(3,3'-iron-1,2,1',2'-dicarbollide)(-1)]ate [Fe(CBH)] (FESAN) against snake venom phosphodiesterase (svPDE, 3'→5'-exonuclease). Contrary to the previously observed protective effect of carborane (CBH) modifications, the B-ASOs containing a metallacarborane moiety at the 5'-end of the oligonucleotide chain were hydrolyzed faster than their parent nonmodified oligomers.

Boron clusters as a platform for new materials: composites of nucleic acids and oligofunctionalized carboranes (CBH) and their assembly into functional nanoparticles.

Nucleic acids are key biomolecules in all life forms. These biomolecules can encode and transfer information via Watson-Crick base-pairing interactions and can form double-stranded structures between complementary sequences with high precision. These properties make nucleic acids extremely successful in applications in materials science as nanoconstruction materials.

Cytochrome c Catalyzes the Hydrogen Peroxide-Assisted Oxidative Desulfuration of 2-Thiouridines in Transfer RNAs.

The 5-substituted 2-thiouridines (R5S2Us) present in the first (wobble) position of the anticodon of transfer RNAs (tRNAs) contribute to accuracy in reading mRNA codons and tuning protein synthesis. Previously, we showed that, under oxidative stress conditions in vitro, R5S2Us were sensitive to hydrogen peroxide (H O ) and that their oxidative desulfuration produced 5-substituted uridines (R5Us) and 4-pyrimidinone nucleosides (R5H2Us) at a ratio that depended on the pH and an R5 substituent. Here, we demonstrate that the desulfuration of 2-thiouridines, either alone or within an RNA/tRNA chain, is catalyzed by cytochrome c (cyt c).

N-Acyl-phosphoramidates as potential novel form of gemcitabine prodrugs.

Gemcitabine (dFdC) is a cytidine analog remarkably active against a wide range of solid tumors. Inside a cell, gemcitabine is phosphorylated by deoxycytidine kinase to yield gemcitabine monophosphate, further converted to gemcitabine di- and triphosphate. The most frequent form of acquired resistance to gemcitabine in vitro is the deoxycytidine kinase deficiency.

Synthesis and an antiviral activity evaluation of nucleoside 5´-O-(N-acyl) phosphoramidates.

Background: pyrimidine nucleoside analogues represent an established class of clinically useful antiviral agents. Once inside the cell, they are activated by a series of intracellular phosphorylation steps to produce 5´-triphosphate derivatives. In many cases, nucleoside analogues are poor substrates for the cellular kinases needed for their activation.