MicroRNAs are short non-coding molecules which regulate translation in a gene-specific manner. MicroRNA isoforms that differ by few extra or missing nucleotides at the 5'-terminus (5'-isomiR) show strikingly different target specificity. This study aimed to identify functional roles of 5′-isomiR in colorectal cancers. Transcriptomic targets of microRNA isoforms were predicted using bioinformatics tools miRDB and TargetScan. The sets of putative targets identified for 5′-isomiR were integrated with mRNA and microRNA sequencing data for primary colorectal tumors retrieved from The Cancer Genome Atlas Colon Adenocarcinoma (TCGA-COAD) database. The network of interactions among miRNA, their targets and transcription factors was built using the miRGTF-net algorithm. The results indicate that microRNA isoforms highly expressed in colorectal cancer and differing by a single nucleotide position at the 5'-terminus have ≤ 30% common targets. The regulatory network of interactions enables identification of the most engaged microRNA isoforms. Anti-correlated expression levels of canonical microRNA hsa-miR-148a-3p and its putative targets including CSF1, ETS1, FLT1, ITGA5, MEIS1, MITF and RUNX2 proliferation regulators suggest an anti-tumor role for this molecule. The canonical microRNA hsa-miR-203a-3p|0 and its 5′-isoform bind different sets of anti-correlated putative targets, although both of them interact with genes involved in the epithelial-mesenchymal transition: SNAI2 and TNC.
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Chronic myeloproliferative disorders (CMPD) include hemoblastoses with abnormal proliferation of myeloid lineages and concomitant alterations in the peripheral blood indicators. The aim of this study was to assess the frequency and structure of ophthalmic complications as a quality of life factor in patients with CMPD. A group of patients with hemoblastoses of this type (n = 41) were surveyed using National Eye Institute Visual Function Questionnaire-25 along with a comprehensive examination by noninvasive ophthalmological techniques. The patients typically reported impaired visual acuity, visual discomfort and foreign body sensation in the eyes. Though many of the patients assessed their general health and vision as satisfactory, the vast majority (68.3%) expressed serious concerns about their visual abilities. The ophthalmological examination revealed various defects including refractive errors (61%), corkscrew dilation and tortuosity of conjunctival and retinal vessels (77.9%), recurrent subconjunctival hemorrhages (39%) and dilated optic nerve sheaths (36.6%). The survey data indicate that visual impairments significantly affect quality of life in patients with CMPD. Overall, the results underscore the importance of interdisciplinary approach in the management of patients with CMPD to enable early diagnosis and feasible correction of the ophthalmic component.
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Systemic nature of the human body response to SARS-CoV-2 requires dedicated analysis at the molecular level. COVID-19 during pregnancy affects maternal health and may entail complications in the early neonatal period and possibly long-term consequences for the offspring. The aim of the study was to assess the impact of COVID-19 on amino acid profiles in maternal venous blood, amniotic fluid and umbilical cord blood in order to develop a diagnostic panel accounting for possible consequences. The main group included 29 pregnant patients with a confirmed diagnosis of COVID-19 and the control group included 17 somatically healthy pregnant women. Amino acid profiles of the biological fluids were measured by high-performance liquid chromatography combined to mass spectrometry (HPLC-MS) and assessed in logistic regression models. The analysis revealed altered content of certain amino acids, their biosynthetic precursors and metabolites in the biological fluids collected from patients with COVID-19 possibly reflecting the development of systemic inflammatory reaction and associated changes in gene expression profiles. These findings may guide further research into health outcomes for neonates born from mothers infected with SARS-CoV-2 during pregnancy. The study may help to develop advanced recommendations and differential care protocols for pregnant women and newborns diagnosed with COVID-19.
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The spread of Mycobacterium tuberculosis drug resistance accentuates the demand for anti-tuberculosis drugs with a fundamentally new mechanism of action without conferring cross-resistance. G-quadruplexes (G4, non-canonical DNA structures) are plausible new drug targets. Although G4-stabilizing ligands have been shown to inhibit mycobacterial growth, the exact mechanism of their action is uncertain. The aim of this study was to assess a possible correlation between putative G4 elements in a model mycobacterial strain M. smegmatis MC2155 and transcriptomic changes under the action of subinhibitory concentrations of G4 ligands BRACO-19 and TMPyP4. We also planned to compare the results with corresponding data previously obtained by us using higher, inhibitory concentrations of these ligands. For BRACO-19, we identified 589 (316↑; 273↓) and 865 (555↑; 310↓) differentially expressed genes at 5 µМ and 10 µМ, respectively. For TMPyP4, we observed the opposite trend, the number of differentially expressed genes decreased at higher concentration of the ligand: 754 (337↑; 417↓) and 702 (359↑; 343↓) for 2 µМ and 4 µМ, respectively. Statistical analysis revealed no correlation between ligand-induced transcriptomic changes and genomic localization of the putative quadruplex-forming sequences. At the same time, the data indicate certain functional specificity of the ligand-mediated transcriptomic effects, with TMPyP4 significantly affecting expression levels of transcription factors and arginine biosynthesis genes and BRACO-19 significantly affecting expression levels of iron metabolism and replication and reparation system genes.
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