INFLUENCE OF SEROLOGICAL MARKERS OF BLOOD GROUPS UPON THE DEVELOPMENT OF VISUAL MEMORY IN HIGH SCHOOLERS AND STUDENTS.

OBJECTIVE: The aim: To investigate the influence of serological markers of blood groups of the AB0 system upon the development of short-term visual memory in high schoolers and students. PATIENTS AND METHODS: Materials and methods: The research involved 13-16-year-old high schoolers (boys) (n = 139) who were involved in various sports: group A - speed and strength sports (n = 74); group B - endurance sports (n = 65). The control group consisted of 13-16-year-old high schoolers (n = 106) and 17-20-year-old students (n = 212) who were not engaged in sports. The study of short-term visual memory was conducted using the "Memory for geometric shapes" method. RESULTS: Results: It was found that high schoolers and students with the 0(I) blood group have the best associative coupling with the properties of short-term visual memory. CONCLUSION: Conclusions: The use of serological markers of blood groups according to the AB0 system is possible in the genetic prediction of the development of visual memory in high schoolers and students. Herewith, the associative coupling is more pronounced in juvenility than in adolescence.

Long interspersed nuclear element-1 methylation status in the circulating DNA from blood of patients with malignant and chronic inflammatory lung diseases.

Along with other malignant diseases, lung cancer arises from the precancerous lung tissue state. Aberrant DNA methylation (hypermethylation of certain genes and hypomethylation of retrotransposons) is known as one of the driving forces of malignant cell transformation. Epigenetic changes were shown to be detectable in DNA, circulating in the blood (cirDNA) of cancer patients, indicating the possibility to use them as cancer markers. The current study is the first to compare the Long interspersed nuclear element-1 (LINE-1) methylation level in the blood from lung cancer patients before treatment versus different control groups as healthy subjects, patients with bronchitis and patients with chronic obstructive pulmonary disease (COPD). The concentration of LINE-1 methylated fragments, region 1 (LINE-1 methylated, LINE-1-met) was estimated by quantitative methyl-specific PCR. The total concentration of the circulating LINE-1 copies was measured by qPCR specific for LINE-1 region 2, which was selected due to its CpG methylation-independent sequence (LINE-1-Ind). Both LINE-1 methylation level and LINE-1 methylation index (LINE-1-met/LINE-1-Ind ratio) was decreased in lung cancer patients compared with the joint control group (healthy subjects + patients with bronchitis + COPD patients) (Mann-Whitney U-test, P = 0.016). We also found that the tendency of LINE-1 methylation index decreases in the cirDNA from lung cancer patients versus COPD patients (Mann-Whitney U-test, P = 0.07). Our data indicate that the quantitative analysis of the LINE-1 methylation level in the cirDNA is valuable for discrimination of lung cancer patients from patients with chronic inflammatory lung diseases.

Cell-Free miRNA-141 and miRNA-205 as Prostate Cancer Biomarkers.

Expression levels of five miRNAs (miR-19b, miR-21, miR-126, miR-141, miR-205) were measured in the plasma of healthy donors and prostate cancer patients. It was shown that miR-141 expression level efficiently discriminates early stage prostate cancer patients and correlates with the Gleason score.

A phenol-free method for isolation of microRNA from biological fluids.

MicroRNAs (miRNAs) found in biological fluids such as blood and urine have been identified as promising biomarkers for many human disorders, including cancer, cardiopathies, and neurodegenerative diseases. However, circulating miRNAs are either encapsulated into vesicles or found in complexes with proteins and lipoproteins and, thus, require a special approach to their isolation. Acid phenol-chloroform extraction can solve this problem, but it is a labor-intensive procedure that relies heavily on the use of hazardous chemicals. Here we describe a fast and simple phenol-free protocol for miRNA isolation from biofluids. MiRNA is extracted from complexes with biopolymers by a high concentration of guanidine isothiocyanate combined with water/organic composition of solvents. Purification is finished using silica-based spin columns. Comparison of miRNA isolation from blood plasma and urine using the single-phase method and acid phenol-chloroform extraction by means of radioisotope spike-ins and quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) showed similar performance of the two methods.

A comparative study of cell-free apoptotic and genomic DNA using FISH and massive parallel sequencing.

OBJECTIVE: Study of circulating DNA (cirDNA) generation mechanisms with respect to their influence on the content of cirDNA is very important since it could indicate the best molecular targets for diagnostic applications. Since apoptosis was shown to be one of the main sources of cirDNA, we performed in vitro comparative study of cell-free apoptotic and genomic DNA (gDNA). METHODS: DNA isolated from culture medium of apoptotic human umbilical vein endothelial cells (cm-apoDNA) and the gDNA from the same living cells was analyzed using FISH and sequenced on SOLiD 3 platform. RESULTS/CONCLUSIONS: FISH demonstrates overrepresentation of C-positive chromosome regions in cm-apoDNA. SOLiD 3 data show enrichment of cm-apoDNA for Alu repeats: the content of AluJ, AluS and AluY repeats was, respectively, 2.47-fold (standard deviation (SD) 3.6%), 2.45-fold (SD 5.5%) and 2.79-fold (SD 6.1%) higher in cm-apoDNA. By contrast, some of L1 elements were underrepresented in cm-apoDNA: the content of L1MA and L1ME was, respectively, 1.4-fold (SD 22%) and 1.45-fold (SD 9%) lower in cm-apoDNA. In contrast to FISH, these data and the predominant location of Alu repeats in euchromatic regions evidence the non-uniform gDNA degradation during apoptosis leading to the enrichment of cm-apoDNA with coding sequences.