Volume 36, Issue 1

Metal nanoclusters (NCs) are novel materials with low cytotoxicity, high chemical stability, intense luminescence, etc. These characteristics are in great demand during biomarker detection and bioimaging. These properties of metal NCs are exploited by colorimetric, luminescent, and Raman tiny sensors. Neopterin (Nep) is used in medicine as a biomarker of inflammation and immune system activation, cancer, COVID-19, etc. The clusters of Au, Ag, and Cu with magic atom numbers m * equal to 2 and 10 were studied. Gibbs energy of complexation ( E b ) has been established using density functional theory (DFT). The highest E b was determined for the complexes of Au 2 + {\text{Au}}_{2}^{\text{+}} and Cu 2 + {\text{Cu}}_{2}^{\text{+}} in an alkaline aqueous solution. As a rule, clusters change their symmetry upon the interaction with Nep; their physicochemical properties are also changed. The detection of Nep with Au and Cu NCs seems to be prospective using Raman detection. In particular, Raman detection of Nep should be done using Cu 9 NC, which interacts with all three Nep functional groups (pyrazine, pyrimidine, and side substituent) and causes significant chemical enhancement and shift of the Raman signal. The usage of coinage metal clusters and nanoparticles is expected for precise Nep detection in the near future.

Objective Data mining was applied to explore the expression, functional enrichment, and signal pathway of methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) gene in non-small cell lung cancer (NSCLC) and its relationship with patient prognosis. Methods The expression of MTHFD2 gene in NSCLC and its adjacent tissues was studied by bioinformatics data analysis. The biological function and signal pathway of MTHFD2 gene were enriched, and the MTHFD2 protein–protein interaction (PPI) network was constructed in the string database. The relationship between MTHFD2 expression and overall survival (OS), disease free survival (DFS) of NSCLC patients was analyzed in GEPIA database. Results In NSCLC patients, the expression level of MTHFD2 in cancer tissues was significantly higher than that in adjacent normal tissues ( P < 0.05). There were 21 related proteins in the PPI network, and the interaction relationship between proteins was 173 with the average local clustering coefficient of 0.881. The biological process of MTHFD2 and relevant genes was mainly enriched in tetrahydrofolate metabolic process, one-carbon metabolic process, and folic acid metabolic process. The KEGG pathway of MTHFD2 and relevant genes was mainly enriched in one carbon pool by folate, metabolic pathways, and antifolate resistance pathway. The OS of patients with high expression of MTHFD2 gene in lung adenocarcinoma (LUAD) was significantly lower than that of patients with low expression (hazard ratio [HR] = 1.6, P = 0.0041), while the expression level of MTHFD2 was not related to DFS of LUAD (HR = 1.4, P = 0.05), lung squamous cell carcinoma (LUSC; HR = 1.3, P = 0.16), and OS of LUSC (HR = 0.82, P = 0.15). MTHFD2 expression level was correlated with B cells, CD8+ T ( r = 0.143, P < 0.05) and CD4+ T lymphocyte infiltration. Conclusion MTHFD2 gene is highly expressed in NSCLC and participates in the metabolism of folic acid and one carbon unit. Its high expression is related to the poor prognosis of patients and may apply as a potential new target for therapy of NSCLC. However, the primary findings are derived from bioinformatic analyses, which, while valuable, necessitate further validation through further empirical methods.

Helper T (Th) 1 inflammatory cytokines, like interferon gamma, play a role in the active inflammatory phase of ocular allergic diseases in addition to Th2-type cytokines, which are actively involved in the pathogenesis of allergies. Allergic conjunctivitis is one of the most common syndromes in ocular disorders, with a prevalence of 5–22% in the general population. The goal of this study was to evaluate the serum neopterin and immunoglobulin E (IgE) levels, as well as the kynurenine (Kyn)/tryptophan (Trp) ratio as an indicator of indoleamine 2,3-dioxygenase activation, in 44 pediatric patients with seasonal AC (SAC) in comparison with values from 33 healthy children. We also assessed the correlations between these biomarkers and symptom and sign scores. Serum neopterin levels were significantly higher in patients with SAC than in healthy controls ( p = 0.018) and were significantly correlated with all parameters except the sign score among the patients. Serum IgE was also higher ( p < 0.001) and Trp levels were significantly lower ( p = 0.017) among patients, while Kyn levels and the Kyn/Trp ratio did not differ between the groups. In conclusion, our study indicated that both Th1 and Th2 responses are active in SAC, confirming the complex involvement of both cytokines in this pathology.

Polyamines, particularly spermidine, play a vital role in regulating cellular functions and influencing processes such as proliferation, ageing, and immune modulation. This study explores the effects of spermidine on the immunoregulatory pathway of tryptophan breakdown, which is mediated by indoleamine 2,3-dioxygenase 1 (IDO-1), as well as on neopterin synthesis, in peripheral blood mononuclear cells. Spermidine treatment was found to suppress IDO-1 activity in mitogen-stimulated cells in a dose-dependent manner without affecting neopterin synthesis. This suppressive effect on tryptophan breakdown contributes to the debate surrounding the health-promoting antioxidant properties of spermidine. However, the divergent regulation of the two immunobiochemical pathways investigated, which share common upstream signalling events, requires further exploration.

Atherosclerosis is an inflammatory disease where activated immune cells are recruited into the artery wall forming artery plaques. Interferon-γ released by T-cells causes macrophage synthesis and release of 7,8-dihydroneopterin, an antioxidant and CD36 down-regulator. 7,8-Dihydroneopterin scavenging of superoxide and hypochlorite generates neopterin, whose measurement has been used as a marker for inflammation in cardiovascular disease. With low oxidative stress levels, 7,8-dihydroneopterin is likely to be the predominant product leading to an underestimate of macrophage activation when measuring neopterin alone. Here we measure both total-neopterin (7,8-dihydroneopterin plus neopterin) and neopterin along with IL-1β, in cardiovascular disease patients presenting with stroke. Plasma neopterin and total neopterin were measured by HPLC in 61 stroke patients undergoing carotid endarterectomy surgery and 61 age-matched controls. Plasma IL-1β was measured by ELISA. Neopterin, total-neopterin, and 7,8-dihydroneopterin were all significantly higher in carotid surgery patients than age-matched controls. Total-neopterin showed the greatest difference between patients and controls ( p  ≤ 0.001). There was no significant difference in IL-1β levels between the stroke patients and healthy controls. The study shows that macrophage inflammation is elevated in cardiovascular disease patients presenting with stroke and the measurement of total neopterin is a more effective indicator of macrophage activation than neopterin alone.

The study aimed to evaluate the effects of occupational exposure on the cellular immune response by measuring neopterin release and the kynurenine pathway and to assess trace element status and heavy metal exposure. The study group consisted of 30 male e-waste recycling workers who underwent detailed occupational anamnesis and a comprehensive physical examination. Concentrations of essential trace elements (Cr, Co, Cu, Mn, Mo, Ni, Se, and Zn) and heavy metals (Sb, Cd, and Pb) were measured in whole blood or serum samples using inductively coupled plasma mass spectrometry (ICP-MS). Serum tryptophan (Trp) and kynurenine (Kyn) levels were determined by high-performance liquid chromatography (HPLC), and serum neopterin concentrations were quantified using a commercial enzyme-linked immunosorbent assay (ELISA) kit. Serum neopterin, Trp, and Kyn concentrations were 7.8 ± 0.7 nmol/L, 54 ± 2 μmol/L, and 0.5 ± 0.04 μmol/L, respectively. The estimated indoleamine 2,3-dioxygenase (IDO) activity, expressed as the Kyn/Trp ratio, was 8.8 ± 0.8 μmol/mmol. Elevated levels of individual metals, except for Pb, did not significantly alter neopterin release or kynurenine pathway activity (all, p  > 0.05). Blood Pb levels showed positive correlations with both Sb and neopterin concentrations, whereas they were negatively correlated with Cu levels (all, p  < 0.05). These results indicate that e-waste recycling workers are exposed to multiple heavy metals, suggesting potential inhalation exposure, and that such exposure may influence trace element status, neopterin release, and the kynurenine pathway without inducing pronounced changes. Further studies with larger populations are warranted to confirm these findings and to better characterize the health impact of multiple metal exposure. Occupational safety measures should be strengthened to minimize such exposures.

Melatonin in human breast milk follows a circadian rhythmicity and serves as a crucial chronobiological signal for neonatal development. Preterm infants are particularly vulnerable to melatonin deficiency due to the immature pineal gland function. Accurate analytical methods are essential for characterizing temporal patterns and assessing clinical relevance. We developed and validated a sensitive LC-MS/MS method for melatonin quantification in breast milk using liquid-liquid extraction with ethyl acetate. The method employed melatonin-d4 as internal standard and scheduled multiple reaction monitoring. Validation followed Eurachem and FDA guidelines and the method was applied to paired daytime and nighttime breast milk samples from mothers of preterm infants ( n  = 80). The method demonstrated excellent analytical performance with an LLOQ of 4.8 pg/ml, intraday and interday precision <5 %, and 97 % extraction efficiency. Nighttime melatonin concentrations (27.5 ± 16.8 pg/ml) were significantly higher than daytime levels (9.0 ± 10.0 pg/ml, p < 0.0001). Circadian variation was maintained across all lactational stages (colostrum, transitional, and mature milk). This validated LC-MS/MS method enables reliable quantification of physiological melatonin concentrations in breast milk and confirms circadian rhythmicity across lactation stages. The simplified sample preparation and robust performance make it suitable for clinical studies investigating chrononutrition and neonatal chronobiological development.