Oxidative stress may play a role in the recurrent miscarriage (RM) with no known etiology. This study was conducted to investigate the association of polymorphisms in oxidative stress-related genes with idiopathic RM. A total of 331 idiopathic RM patients and 197 controls were genotyped for ABCB1 rs1045642, CYP1A1 rs1048943 and rs4646903, COMT rs4680, CAT rs17880664, GCLC rs17883901, GPX4 rs713041, NRF2 rs6721961, SOD2 rs4880, and OGG1 rs1052133. A protective effect of COMT rs4680-G allele on RM was shown in individual SNP analysis: P = 0.0016, OR = 0.47, 95% CI 0.29–0.75. The multi-factor dimensionality reduction (MDR) approach revealed gene–gene interactions for ABCB1, COMT, GPX4, and OGG1 genes. Cumulative gene risk score analysis demonstrated that more than three risk alleles in the genes ABCB1 (rs1045642-T), COMT (rs4680-A), GPX4 (rs713041-T), and OGG1 (rs1052133-G) were associated with idiopathic RM P = 1.2 × 10^{− 3}, OR = 1.97, 95% CI 1.31–2.97. In silico data interpreting by GeneMANIA analysis revealed genetic, physical, pathway, and coexpression networks for these four genes.

COVID-19 patients with acute respiratory distress syndrome (ARDS) have an immune imbalance when systemic inflammation and dysfunction of circulating T and B cells lead to a more severe disease. Using TREC/KREC analysis, we studied the level of mature naive T and B cells in peripheral blood of COVID-19 patients and its relationship with clinical and laboratory data. TREC/KREC analysis was performed by multiplex real-time quantitative PCR on a sample of 36 patients aged 45 years or younger. The reduced TREC/KREC level was observed in ARDS patients compared with non-ARDS patients, and similar results were found for the deceased patients. During days 6 to 20 of hospitalization, a higher neutrophil-to-lymphocyte ratio (NLR) was detected in ARDS patients compared with non-ARDS patients. TREC/KREC negatively correlated with NLR; the highest correlation was recorded for TREC per 100,000 cells with the coefficient of determination R² = 0.527. Thus, TREC/KREC analysis is a potential prognostic marker for assessing the severity and outcome in COVID-19.

Pneumonia is an acute infectious disease with high morbidity and mortality rates. Pneumonia’s development, severity and outcome depend on age, comorbidities and the host immune response. In this study, we combined theoretical and experimental investigations to characterize pneumonia and its comorbidities as well as to assess the host immune response measured by TREC/KREC levels in patients with pneumonia. The theoretical study was carried out using the Columbia Open Health Data (COHD) resource, which provides access to clinical concept prevalence and co-occurrence from electronic health records. The experimental study included TREC/KREC assays in young adults (18–40 years) with community-acquired (CAP) (n = 164) or nosocomial (NP) (n = 99) pneumonia and healthy controls (n = 170). Co-occurring rates between pneumonia, sepsis, acute respiratory distress syndrome (ARDS) and some other related conditions common in intensive care units were the top among 4170, 3382 and 963 comorbidities in pneumonia, sepsis and ARDS, respectively. CAP patients had higher TREC levels, while NP patients had lower TREC/KREC levels compared to controls. Low TREC and KREC levels were predictive for the development of NP, ARDS, sepsis and lethal outcome (AUC_TREC in the range 0.71–0.82, AUC_KREC in the range 0.67–0.74). TREC/KREC analysis can be considered as a potential prognostic test in patients with pneumonia.