Diabetic nephropathy (DNP) is a serious complication of type 2 diabetes mellitus (T2D), leading to early disability and mortality from end-stage renal failure. Experimental and clinical studies have shown the leading role of oxidative stress-induced damage to macromolecules, including DNA, in the development and progression of DNF against the background of hyperglycemia. On the contrary, repair of these DNA lesions serves as a signal to end ongoing oxidative stress. The key DNA repair enzyme is 8-oxoguanine DNA glycosylase, encoded by the OGG1 gene. The aim of this study was to analyze the associations of five polymorphic variants (rs2072668, rs1052133, rs293795, rs2304277, and rs6443265) of the OGG1 gene with the risk of developing DNF in patients with type 2 diabetes. The study included 1461 patients with type 2 diabetes, 577 of whom were diagnosed with DNF. DNA genotyping was performed by real-time polymerase chain reaction using allele-specific fluorescently labeled probes. Associations were established between the rs293795-G/G genotype (OR = 1.97, 95% CI = 1.23-3.16, p = 0.007) and the rs2072668C-rs1052133C-rs293795G-rs2304277G-rs6443265C haplotype (OR = 1.30, 95% CI = 1.06-1.60, p = 0.012) of the OGG1 gene with a predisposition to DNF in the background of T2D. Moreover, six OGG1 diplotypes associated with an increased risk of DNF and one diplotype associated with a reduced risk of DNF in patients with T2D were identified. Thus, in our study, we presented for the first time data on the association of the OGG1 gene polymorphism with DNF, which creates a scientific foundation for further research on the contribution of disturbances in the DNA oxidative damage repair system to the development of microvascular complications of T2D.
VIEWS 548
Follicular helper (Tfh) and follicular regulatory (Tfr) T cells play critical roles in inducing and controlling B cell responses, including the generation of high-affinity humoral immunity, the antibody class-switching, and the prevention of autoreactivity. Successful Tfh responses are linked to robust vaccine-induced neutralizing antibody production and efficient clearance of various pathogens. Conversely, dysregulation of follicular T cells is often linked to autoimmune diseases and allergic reactions. Furthermore, these cells are implicated in the formation of ectopic lymphoid structures (ELS), contribute to certain vascular pathologies, and hold prognostic value in several cancers. Consequently, the analysis of follicular T cell subpopulations in human peripheral blood is increasingly utilized to investigate the mechanisms underlying various diseases. In this opinion article, the current understanding of follicular T cell subsets, their functions, and the evolving methods for analyzing their circulating counterparts in human blood are discussed. In the author's opinion, the central unresolved questions remaining in the field are the precise phenotypic definition of circulating Tfr cell subpopulations, the elucidation of their developmental trajectory from precursors cells to mature regulatory forms, and the identification of their anatomical differentiation niches. The collection and translation of these essential data into reliable cellular signatures for peripheral blood analysis are critical for advancing personalized patient prognosis and developing tailored therapies.
VIEWS 493
Salmonellosis remains one of the leading causes of bacterial gastrointestinal infections in humans and animals. Molecular diagnostics has dramatically reshaped the diagnostic landscape for Salmonella infection; however, it remains time- and resource-intensive. Isothermal DNA amplification, for example loop isothermal amplification (LAMP), performed at a constant temperature, is the basis for the development of rapid diagnostic tests that can be adapted to the point-of-care (PoC) formats and implemented in resource-limited settings or remote from centralized laboratories. The aim of this study was to develop and validate a novel LAMP-based method for detecting Salmonella enterica in human stool samples, wherein amplification results are monitored using a loop primer labeled with a fluorophore and an internal quencher. The proposed method achieves a limit of detection (LoD95) of 250 copies per reaction, with a sensitivity of 86.84% (95% CI: 71.91–95.59%) and specificity of 96.49% (95% CI: 87.89–99.57%) relative to qPCR, and demonstrates increased robustness against DNA amplification inhibitors present in fecal samples. Incorporation of distinct fluorophores into loop primers for FLP-LAMP targeting different genes could potentially enable multiplexing and simultaneous detection of multiple pathogens, thereby expanding the diagnostic utility of isothermal amplification.
VIEWS 485
Experimental studies have demonstrated the protective role of ectonucleotidases — particularly CD39 and CD73 — in limiting inflammation connected to a liver pathology. However, their expression in metabolic-associated fatty liver disease (MAFLD) has not been thoroughly investigated. This study aimed to evaluate the mRNA levels of the ENTPD1 and NT5E genes, which encode CD39 and CD73, respectively, in patients with different forms of MAFLD (liver steatosis (LS) and metabolic-associated steatohepatitis (MASH)), and to assess the expression of CD39- and CD73-positive cells following immune cell activation in vitro. The sample included 29 healthy donors and 56 MAFLD patients. We measured the mRNA levels of the ENTPD1 and NT5E genes, pro-inflammatory cytokines (IL-6, TNFα), fragmented cytokeratin-18, and the blood content of CD39+ cells. Another parameter measured in vitro was the effect of immune cell activation on the proportion of CD39+ and CD73+ cells in patients with MASH and healthy donors. The expression of the ENTPD1 gene (p = 0.007 vs. control group; p = 0.010 vs. LS group) and the proportion of CD39+ cells among monocytes (p = 0.004 vs. control group; p = 0.003 vs. LS group) and lymphocytes (p = 0.034 vs. control group) were lower in the MASH group compared with both the control and LS groups. Activation of cells from MASH patients increased the proportion of CD39+ lymphocytes, but not that of CD14+ monocytes. It also increased the proportion of CD73+ cells among both lymphocytes and CD14+ monocytes. Thus, further investigation into the roles of CD39 and CD73 in the context of MAFLD progression represents a promising avenue for future research.
VIEWS 446
Personalization of selecting a target for rTMS is a problem, solving which can significantly increase the method efficacy. Stimulation of the key hubs of individual-level resting-state networks represents an approach to personalization. The study aimed to develop an rTMS personalization method based on the selection of individual frontoparietal control network (FPCN) hubs and assessment of their localization variability. To determine the FPCN hubs, individual maps were built using the FPCN group mask as a seed. The searchlight algorithm with the sphere radius of 5 mm was used to select targets within the dorsolateral prefrontal cortex (DLPFC) and posterior parietal cortex (PPC). The target spatial localization variability and correctness of using the routine “5 cm rule” for the DLPFC localization were analyzed. In 24 healthy volunteers (9 males, average age 29±7 years), high interindividual variability of targets was demonstrated. In no area is there a universal position of the stimulation coil that would effectively stimulate targets in all volunteers. Spatial dispersion of points is higher in the DLPFC (volumes of the polyhedra containing the point sets are 2095 mm3 in the DLPFC and 739 mm3 in the PPC). All individual targets in the DLPFC are located within the FPCN mask, while in the PPC some targets are outside this mask. The average distance between the М1 zones and DLPFC is 64±13 mm. In 75% of the subjects, this exceeds 5 cm, which confirms that it was incorrect to use the routine “5 cm rule” for coil positioning in the majority of subjects. An algorithm to select personalized targets for rTMS based on the resting-state fMRI data in the DLPFC and PPC being the key FPCN hubs has been developed.
VIEWS 480
In psychiatric practice, there is a need to develop simple, pathogenetically substantiated biomarkers for prediction of the patient’s current affective status and his/ her status short-term perspective. The study aimed to analyze the association of the affective status of patients with mood disorders with the peripheral blood catecholamine and serotonin levels. The Hospital Anxiety and Depression Scale (HADS) was used for affective status evaluation. Concentrations of catecholamines (adrenaline, norepinephrine, and dopamine) in blood plasma and serotonin in blood serum were assessed by high-performance liquid chromatography (HPLC). The study included 114 individuals with affective disorders, the average age was 34.57 (SD = 10.36) years, the share of females was 64%. We revealed no significant prognostic effects of peripheral blood neurotransmitter levels relative to the current affective status. The serotonin/norepinephrine ratio, the increase in which significantly decreases the risk of clinical depression according to HADS-D considering the patient's sex and age (p = 0.059), turned out to be the only marker at the level of trends. In patients diagnosed with recurrent depressive disorder or depressive episode, a slight decrease in serotonin levels (p = 0.068) compared to the patients diagnosed with the disorders beyond the category of mood disorders is reported. In the same group a negative correlation has been found between the HADS-A scores (anxiety) and norepinephrine levels (Rs = ‒0.410, p < 0.05). The findings suggest that it will be possible to confirm the preliminary results obtained and acquire new data in the expanded clinically homogenous samples.
VIEWS 500
The use of allogenic bone material as a ceramic filler for DLP printing makes it possible to obtain personalized complex-shaped implants combining the matrix biomimetic nature with the additive technology benefits. The study aimed to assess the possibility of using the calcined cortical bone allograft powder as part of photopolymerizable suspension for DLP printing and producing bioceramics with the characteristics comparable to that of synthetic hydroxyapatite by sintering. The bone allograft was subjected to multi-stage specialized treatment involving complete removal of cells with preservation of the intercellular matrix and collagen fiber structure. The calcined medical allograft was crushed, introduced into a photopolymerizable matrix, and used for DLP printing of the samples that were further sintered and analyzed by X-ray diffraction and energy-dispersive spectroscopy methods before and after additive production. The sintered material specific gravity was 81.5%, compressive strength — 75.8 MPa, tensile strength — 12 MPa, Young's modulus — 3.08 GPa, and Vickers hardness — 0.55 GPa, which was within the range of values for porous hydroxyapatite. After DLP printing and sintering the sample phase and elemental composition did not change considerably compared to the source calcined material. The calcined bone allograft powder is suitable for preparing photopolymerizable suspensions and subsequent DLP printing of ceramic samples without deteriorating the material phase and chemical stability. The resulting mechanical properties make it possible to consider this allogenic bone material as a promising candidate for production of personalized implants with sophisticated geometry.
VIEWS 863