Biomarkers of Disease: Discovery and Clinical Applications

Background: Small cell lung cancer (SCLC) carries a dismal prognosis with limited biomarkers for risk stratification. This study aimed to identify circulating prognostic biomarkers. Methods: We prioritized SCLC risk-associated genes using Summary-data-based Mendelian Randomization of pQTL/eQTL, differential expression, and weighted gene co-expression network analysis. Five machine learning approaches were compared to develop a diagnostic model based on ACE, AGER, and IL18R1, trained on GSE149507 and validated in GSE60052. We conducted single-cell transcriptomic analysis using public datasets (GSE150766 and GSE279570) and peripheral blood mononuclear cells (PBMCs) from our extensive-stage cohort. Finally, prioritizing the lead candidate IL18R1, we enrolled a prospective clinical cohort to assess its prognostic utility. A LASSO–Cox prognostic model incorporating plasma IL18R1 and clinical variables was internally validated (7:3 split) for progression-free survival (PFS) prediction. Results: Integrative multi-omics identified ACE, AGER, and IL18R1 as SCLC-protective genes. Elastic Net machine learning identified a two-gene predictive signature (AGER and IL18R1) with robust diagnostic accuracy. Single-cell RNA sequencing revealed the predominant downregulation of ACE, AGER, and IL18R1 in T cells and alveolar type II cells from SCLC patients. PBMC analysis further supported IL18R1 downregulation in CD8⁺ T cells, NK cells, and dendritic cells. In an independent prospective cohort (n = 300), lower plasma IL18R1 levels were independently associated with shorter PFS (HR = 0.997 per unit increase; 95% CI: 0.995–0.999; and p = 0.003), with time-dependent AUCs of 0.77–0.86. Performance in limited-stage disease was inconsistent and requires further validation. A prognostic model incorporating plasma IL18R1 and 11 clinical parameters stratified patients into distinct risk groups (HR = 5.19), showing a strong discriminative ability in extensive-stage SCLC. Conclusions: We identified ACE, AGER, and IL18R1 as protective factors against SCLC progression. Integration of plasma IL18R1 with clinical parameters provides a prognostic tool for extensive-stage SCLC. Full article

Background: Podocyte injury leads to the shedding of podocyte-derived molecules into the urine, which may serve as biomarkers of kidney disease. These molecules could be useful for the early detection of glomerular damage and for monitoring the progression of chronic kidney disease (CKD). Methods: A prospective cohort study was conducted in pediatric patients with CKD stages 1–4 treated at a tertiary care hospital between October 2019 and January 2023. Urinary podocalyxin and creatinine were measured at baseline. Renal function was assessed at baseline and at 12 and 24 months of follow-up. Patients were stratified by CKD stage. Changes in glomerular filtration rate (ΔGFR) were calculated, and correlations with baseline podocalyxin were evaluated using Spearman’s test. Multiple linear regression was used to adjust for confounders. Results: A total of 169 patients were included (median age 11 years). Glomerulopathies were the most frequent etiology (40.8%), and stage 1 was the most prevalent. At 12 months, stage 4 CKD patients showed a positive correlation with ΔGFR (r = 0.709, p = 0.003) and a negative correlation with proteinuria (r = −0.864, p < 0.001). At 24 months, a positive correlation was observed with ΔGFR (r = 0.949, p < 0.001), while an inverse association was observed with GFR. Associations varied according to CKD etiology. Conclusions: The podocalyxin-to-creatinine ratio was positively associated with renal function and negatively with proteinuria in stage 4 CKD, but showed no utility in stages 1–3. Full article

Background: Lung adenocarcinoma (LUAD) is the most common type of lung cancer and a major cause of cancer death. Zinc finger proteins (ZNFs) have been implicated in LUAD progression, functioning either as oncogenes or tumor suppressors. Therefore, an in-depth investigation of ZNFs may contribute to the development of novel diagnostic and therapeutic strategies for LUAD. Methods: Transcriptomic and clinical data were obtained from the TCGA and GEO databases. Prognosis-related ZNF genes were identified using univariate Cox, LASSO, and multivariate Cox regression analyses. An eight-gene ZNF-based prognostic signature was constructed and validated in two independent external cohorts (GSE50081 and GSE26939). A nomogram integrating independent prognostic factors was developed. Immune infiltration, somatic mutation profiles, and drug sensitivity were systematically analyzed. We further focused on FGD3, a key gene from the signature, examining its expression in LUAD cells and tissues, including lorlatinib-resistant models. Results: The prognostic signature comprising TRIM6, TRIM29, CTCFL, FGD3, GATA4, CASZ1, TRAF2, and ZNF322 effectively stratified patients into distinct risk groups with significantly different overall survival (p < 0.05). The risk score, together with T and N stage, served as independent prognostic predictors (n = 500, p < 0.05). High-risk patients exhibited an immune-desert phenotype, increased tumor mutational burden, and distinct drug sensitivity patterns. Notably, FGD3 expression was downregulated in LUAD tissues (n = 14, p < 0.0001) and lorlatinib-resistant cells, and its restoration suppressed resistant cell proliferation and partially reversed drug resistance. Conclusions: This study establishes a promising ZNF-based prognostic model for LUAD, providing a potential tool for risk stratification and individualized therapeutic decision-making. The identification of FGD3 as a potential mediator of drug resistance highlights its promise as a candidate biomarker and therapeutic target in LUAD. Full article

Accurate analysis of prostate cancer (PC)-related biomarkers requires sensing platforms capable of sensitive and multiplex detection in complex biological environments. Herein, we propose a signal-on electrochemical aptamer-based sensor (E-AB) for the simultaneous detection of L-lactate (L-Lac) and prostate-specific antigen (PSA). To maximize analytical performance, two Lac aptamer sensing configurations, single-stranded (ssLac201) and double-stranded (dsLac201), were constructed and comparatively evaluated. The dsLac201 structure displayed more effective background suppression and enhanced target induced signal response. Under optimized conditions, the dsLac201-based sensor exhibited a wide linear range from 500 nM to 10 mM for L-Lac, with a low detection limit of 157 nM and high selectivity. Based on this optimized design, a dual-aptamer electrochemical platform was further engineered through programmable nucleic acid assembly, enabling simultaneous detection of L-Lac and PSA via dual-input signal integration. The dual-target sensor showed broad analytical ranges for both biomarkers (L-Lac: 500 nM–10 mM; PSA: 10 pg mL⁻¹–500 ng mL⁻¹) and retained promising performance in serum samples. This work demonstrates a simple and versatile strategy for multiplex electrochemical biosensing and provides a promising platform for PC-related biomarker monitoring and clinical biomedical analysis. Full article

Background: Pancreatic cancer is an aggressive malignancy with poor survival. Most patients are diagnosed at advanced or metastatic stages because early disease is often asymptomatic and effective screening tools are lacking. We evaluated a three-marker model comprising serum CA19-9 in combination with the plasma proteins ITIH3 and CEACAM1 for pancreatic ductal adenocarcinoma (PDAC) detection. Methods: Matched plasma and serum samples were collected from 649 participants (250 PDAC cases and 399 controls). Plasma proteins were enriched using high-surface area magnetic covalent organic framework (COF) polymers. Serum CA19-9 was measured using the Tosoh Bioscience immunoassay. The marker panel was trained using a radial-based SVM with repeated 10-fold cross-validation using a set-aside training sample set. The derived model along with a fixed cutoff corresponding to 95% sensitivity in training samples were independently validated using a blinded sample set. Results: In the independent blinded validation, the combined panel of serum CA19-9 with plasma ITIH3 and CEACAM1 achieved an AUC of 0.917 indicating that the three-marker panel maintained strong performance in distinguishing PDAC from controls. At the prefixed threshold, the three-marker panel had a specificity of 53.3% (95% CI: 46.8–59.7%), significantly outperforming CA19-9 alone at 14.5% (95% CI: 10.4–19.7%). Conclusions: In independently blinded validation, combining plasma ITIH3 and CEACAM1 with serum CA19-9 substantially improved diagnostic performance for PDAC, achieving high specificity while maintaining 95% sensitivity compared with serum CA19-9 alone. These findings support further validation of this three-marker panel as a potential PDAC monitoring and detection approach in larger, multicenter studies. Full article

Background: Acute type A aortic dissection complicated by mesenteric malperfusion syndrome (ATAAD-MMPS) is a highly lethal emergency with diagnostic challenges due to rapid progression and non-specific symptoms. This pilot study aimed to characterize the serum metabolomic and lipidomic alterations specific to ATAAD-MMPS and identify potential early diagnostic biomarkers. Methods: Serum samples from healthy controls, patients with uncomplicated ATAAD, and patients with ATAAD-MMPS were analyzed using targeted metabolomics and lipidomics. Multivariate statistical analyses were performed to discriminate between groups and identify differentially abundant metabolites and lipids. Pathway analysis was conducted to explore underlying pathological mechanisms. Results: Metabolomic profiles clearly distinguished ATAAD-MMPS from uncomplicated ATAAD, whereas lipidomic changes were primarily associated with ATAAD itself rather than the presence of mesenteric malperfusion. Metabolic pathway analysis revealed significant perturbations in the citric acid cycle, suggesting mitochondrial involvement as a potential pathological feature. Notably, methylguanidine was uniquely and markedly elevated in the ATAAD-MMPS group, demonstrating potential diagnostic value in distinguishing this lethal complication from uncomplicated ATAAD in this exploratory cohort (AUC = 0.923). Conclusions: This pilot study identifies distinct metabolic signatures associated with mesenteric malperfusion in ATAAD, with mitochondrial metabolic perturbations emerging as a potential contributing mechanism. Methylguanidine represents a candidate early diagnostic biomarker for ATAAD-MMPS, warranting validation in larger prospective studies. These findings provide a foundation for improved diagnostic strategies for this devastating condition. Full article

Background: Heterogeneous nuclear ribonucleoprotein L-like (HNRNPLL) is an RNA-binding protein involved in alternative splicing and immune regulation; however, its role in liver hepatocellular carcinoma (LIHC) remains unclear. Methods: We performed integrative multi-omics analyses using data from TCGA, GEO, and the Human Protein Atlas to evaluate the expression patterns, prognostic value, and potential biological functions of HNRNPLL. Functional enrichment and immune-related analyses were conducted to explore associated pathways. Experimental validation was performed in LIHC cell lines using Western blotting, RT-qPCR, CCK-8, colony formation, and Transwell assays, along with a xenograft mouse model. Results: HNRNPLL was significantly upregulated in LIHC at both transcriptomic and proteomic levels and was associated with advanced clinicopathological features and poor overall survival. Multivariate Cox regression analysis identified HNRNPLL as an independent prognostic factor. Enrichment analyses suggested that HNRNPLL-related genes are mainly involved in cell cycle regulation, mitotic progression, epithelial–mesenchymal transition, and immune-related pathways. In addition, HNRNPLL expression was correlated with immune cell infiltration, tumor mutational burden, microsatellite instability, ferroptosis-related genes, and m6A methylation regulators. Functional experiments demonstrated that HNRNPLL knockdown suppressed proliferation, migration, and invasion of liver cancer cells and inhibited tumor growth in vivo. Conclusions: These findings suggest that HNRNPLL may act as a potential regulator of LIHC progression and is associated with tumor-related biological processes and immune features. HNRNPLL may serve as a candidate biomarker for prognosis and a potential therapeutic target in LIHC, although further mechanistic studies are required. Full article

Background: Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection and remains a leading cause of mortality in intensive care units (ICUs). Although the Sequential Organ Failure Assessment (SOFA) score is widely used for prognostic stratification, organ dysfunction represents a downstream manifestation of sepsis, whereas immune and inflammatory dysregulation may precede overt organ failure. Monocyte distribution width (MDW) is a novel hematological parameter reflecting monocyte activation and is approved for the diagnosis of sepsis; however, its prognostic value and potential role within composite biomarker models in critically ill surgical patients with sepsis remain incompletely defined. Methods: We conducted a prospective, observational, single-center pilot study in two surgical intensive care units between November 2022 and December 2023. Adult patients with sepsis defined according to Sepsis-3 criteria were enrolled. Laboratory and clinical variables—including MDW, neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), procalcitonin (PCT), and SOFA score—were measured on admission and during the first five days of ICU stay. Patient-level median values across five days were used for analysis. The primary outcome was in-hospital mortality. Prognostic performance was assessed using receiver operating characteristic (ROC) curve analysis and logistic regression. A composite bioscore was constructed by combining dichotomized MDW, NLR, CRP, and PCT values. Results: Sixty patients were included; 24 (40%) died during hospitalization. Non-survivors were older and had significantly higher SOFA scores. MDW, NLR, CRP, and PCT were significantly higher in non-survivors. SOFA demonstrated the strongest discriminative ability for mortality prediction (AUC 0.839, 95% CI 0.730–0.948). Among biomarkers, NLR (AUC 0.741) and PCT (AUC 0.714) showed good discriminative performance, while MDW (AUC 0.690) and CRP (AUC 0.662) showed moderate discrimination; MDW exhibited the highest specificity (80.6%). In multivariable analysis with individual biomarkers, only SOFA remained an independent predictor of mortality. The composite bioscore demonstrated good discriminative ability (AUC 0.805) and, when evaluated alongside SOFA, remained independently associated with fatal outcome (OR 11.92, 95% CI 1.76–80.75); however, given the modest sample size and wide confidence intervals, this finding should be interpreted with caution. Repeated-measures correlation analysis revealed no strong collinearity among biomarkers. Conclusions: A composite bioscore incorporating MDW, NLR, CRP, and PCT provides prognostic information comparable to SOFA and remains independently associated with mortality. This approach may complement organ dysfunction-based assessment and support early risk stratification in sepsis. Full article

Background: Traumatic head injury (THI) includes a diverse range of hemorrhagic brain lesions (HBL), which are distinct phenotypes with characteristic pathophysiological mechanisms. Computed tomography (CT) is the cornerstone of the initial assessment and diagnosis; however, its sensitivity is limited, especially in mild head injury. Blood-derived biomarkers, including Neuron-Specific Enolase (NSE) and S-100B, have been extensively studied; however, their efficacy in distinguishing HBL subtypes remains unclear. We evaluated whether circulating serum levels of S-100B and NSE can discriminate between distinct intracranial HBLs and extracranial hemorrhagic lesions (ECH). Methods: This is an interim analysis of a prospective, randomized, double-blind clinical trial including 434 adult patients with blunt THI. HBL phenotypes identified by CT scan included subarachnoid hemorrhage (SAH), subdural hematoma (SDH), epidural hematoma (EDH), and brain contusion (BC). Unique lesions were considered while overlapping lesions were excluded. Subgaleal hematoma (SGH) was included as an example of ECH. Serum S-100B was assessed within 6 h post-injury, while serum NSE was evaluated at admission, 24 h, and 48 h thereafter. Serum NSE and inflammatory cytokines were quantified in duplicates using a Human Magnetic Luminex 5-plex assay, while serum S-100B concentrations were measured separately. Serum epinephrine concentrations were quantified using an ELISA. Biomarker profiles were analyzed based on lesion phenotype, lesion multiplicity, injury pattern, and clinical outcomes, including hospital length of stay (HLOS) and the Glasgow Outcome Scale—Extended (GOSE). Results: Admission median S-100B levels were higher in patients with SAH (495 pg/mL) and lower in those with SGH (191 pg/mL); however, they did not show statistically significant difference among HBL phenotypes. They were significantly higher in patients with polytrauma TBI (420 pg/mL) compared to isolated TBI (258 pg/mL). Baseline and 48 h NSE concentrations were significantly higher in SDH (25,089 and 28,438 pg/mL) than in other THI lesions (p = 0.04). There were no statistically significant changes in NSE values over time across all THI lesions except for SDH in which they raised more after 48 h (p = 0.02). They had a significant drop in polytrauma over the time (p = 0.001). Compared to intracranial lesions, S-100 B levels were significantly lower in SGH and in skull fractures without intracranial hematomas. Both S-100B and NSE levels were elevated in individuals with unfavorable GOSE scores. Conclusions: In this secondary exploratory analysis, elevated serum NSE and S-100B levels discriminate between extra- and intracranial lesions and appear to represent distinct but complementary aspects of THI, indicating neuronal damage and its temporal evolution, and predicting clinical and functional outcomes. The present findings reflect association and not causation. Future studies incorporating larger or multicenter cohorts, volumetric imaging, and long-term outcomes are required to validate and refine biomarker-guided algorithms for personalized THI care. Full article

Background/Objective: Major depressive disorder (MDD) is a common mental illness that lacks objective diagnostic biomarkers and has a complicated pathogenesis. Peripheral blood-based gene expression profiling provides a potential, non-invasive method to identify the molecular markers associated with risk stratification and depression severity.This study aimed to investigate the gene expression of five candidate genes—CD19, MTPAP, PER3, GAR1, and SLC25A26—in the peripheral blood of drug-naïve patients with MDD and to evaluate their potential as diagnostic biomarkers. Methods: Peripheral blood samples were collected from 100 newly diagnosed, drug-naïve MDD patients and 100 age- and sex-matched healthy controls. The total RNA was extracted and reverse-transcribed for quantitative real-time PCR analysis. Fold change and ∆∆Ct values were calculated for each gene, followed by statistical analysis using t-tests and ANOVA. Receiver operating characteristic (ROC) curves were used to evaluate diagnostic performance. Gene co-expression and pathway enrichment analyses were conducted to explore functional relevance. Results: Significant upregulation was observed for CD19 (fold change = 6.15, p = 6.17 × 10⁻¹⁰), MTPAP (fold change = 3.99, p = 1.74 × 10⁻⁸), and PER3 (fold change = 2.42, p = 5.33 × 10⁻⁶) in MDD. GAR1 showed modest upregulation (fold change = 1.26, p = 0.47), while SLC25A26 (fold change = 1.24, p = 0.47) was not significantly altered. Combined ROC analysis yielded an AUC of 0.885, indicating a strong discriminative ability. Gene expression correlated with depression severity (HAM-D and PHQ-9). Conclusions: This study identifies CD19, MTPAP, and PER3 as promising peripheral blood biomarkers for MDD, with potential implications for early diagnosis, severity assessment, and personalized treatment strategies. Full article

Background/Objectives: Natural killer (NK) cells are essential mediators of innate immune defense and play a key role in tumor surveillance following liver transplantation (LT). Despite this, the prognostic relevance of pre-transplant NK cell activity in living donor LT (LDLT) has not been fully established. Methods: This retrospective analysis included 134 adult patients who underwent LDLT. NK cell activity was evaluated prior to transplantation using interferon-γ release assays and classified as low (<10 pg/mL) or high (≥10 pg/mL). Overall survival (OS) was assessed for all participants, whereas recurrence-free survival (RFS) was analyzed patients with HCC. Results: Patients classified as having high NK activity (≥10 pg/mL) experienced significantly better overall survival compared to those with low activity (log-rank p = 0.032). In the multivariate analysis, high NK activity showed a strong trend toward improved overall survival (HR, 0.52; 95% CI, 0.26–1.04; p = 0.063). Among recipients with HCC, high NK activity was associated with a markedly improved recurrence-free survival (log-rank p = 0.004). Multivariate Cox regression further established NK activity as an independent factor for tumor recurrence (HR, 0.27; 95% CI, 0.08–0.87; p = 0.028). Conclusions: Pre-transplant NK cell activity independently predicts both survival and recurrence following LDLT. Full article

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by complex immune cell associations and continuous joint damage. Personalized clinical assessment and treatment options for RA remain hindered by a precision gap due to an inability to precisely match current global treatment strategies to individual molecular and spatial disease profiles. Recent advances in spatial transcriptomics and proteomics offer unprecedented opportunities to map molecular heterogeneity and spatial heterogeneity within RA tissues by identifying immune microenvironments activated during the disease, thus enabling precise therapeutic targeting. These techniques address the precision gap in RA by identifying distinct pathogenic subpopulations and cellular niches, providing insights into the biomolecules that possess significant therapeutic responses and are involved in disease progression. This review synthesizes recent findings demonstrating how spatial omics technologies, including spatial transcriptomics and proteomics, together with artificial intelligence, are transforming precision rheumatology. Full article

Background/Objectives: Intensive care unit-acquired weakness (ICUAW) is a frequent complication characterized by symmetrical and proximal limb muscle weakness. Its diagnosis is primarily based on clinical symptoms; however, ICUAW assessment can often be uncertain. Blood biomarkers have not yet been widely investigated for this purpose. Serum gelsolin (GSN) is synthesized by skeletal muscle cells. It plays a crucial role in binding extracellular actin filaments and pro-inflammatory cytokines. In sepsis-associated ICUAW, GSN levels might massively decrease due to their buffering activity and muscle wasting. We elucidated the predictive capacity of GSN regarding ICUAW and its additional diagnostic/prognostic potential in sepsis compared to classical parameters. Methods: We recruited septic and non-septic ICU patients for our follow-up study. Patients were retrospectively categorized into ICUAW positive (n = 26) and negative (n = 47) groups based on their clinical characteristics. Sera were collected on the 1st, 2nd and 3rd days of ICU stay. Ambulatory patients (n = 34) served as controls. GSN levels were measured by our previously developed automated immunoturbidimetric assay. Clinical and laboratory parameters were collected from our hospital information system. Results: Admission GSN levels were significantly reduced in ICU patients compared to controls (median: 11.60 vs. 75.99 mg/L). ICUAW positive patients had significantly lower admission GSN levels than ICUAW negative patients (median: 8.10 vs. 14.30 mg/L), and a similar tendency was observed during follow-up. GSN showed predictive capacity regarding ICUAW (ROC AUC: 0.711, p < 0.01), especially when combined with albumin (ROC AUC: 0.750, p < 0.01). The combination of admission GSN, albumin, and procalcitonin demonstrated significant diagnostic performance (ROC AUC: 0.803) regarding the requirement for invasive ventilation, and GSN had prognostic value for 28-day mortality as well. Conclusions: GSN might serve as an intriguing marker in the prediction of ICUAW, especially when combined with albumin. The parallel decline of GSN and albumin could reflect the combined effects of systemic inflammation and muscle wasting seen in ICUAW. Full article

Background: Approximately half of patients with diabetes mellitus (DM) develop diabetic distal symmetric sensorimotor polyneuropathy (DM-DSPN), yet no reliable biomarkers for its early detection exist. This study assesses cystatin C (CysC), a naturally occurring protein, in diabetic persons with and without large-fiber DM-DSPN. Methods: This study involved persons with diabetes (HbA1c > 6.5%) visiting specialized diabetic clinics at King Saud University Medical City (KSUMC) in Riyadh, Saudi Arabia. Clinical features, laboratory data, nerve conduction findings, and serum CysC levels were assessed. DM-DSPN was diagnosed if signs of large nerve fiber impairment were present in the lower extremity in a symmetric and length-dependent pattern. Participants were designated as diabetic with or without large-fiber DSPN (+DM/+DSPN and +DM/−DSPN, respectively) based on validated composite scores of nerve conduction attributes. Results: A total of 52 persons with diabetes were included for analysis (24 with +DM/+DSPN and 28 with +DM/−DSPN). One participant had type 1 DM; all remaining participants had type 2 DM. In multivariate regression, serum CysC ≥ 0.88 mg/L was significantly associated with DM-DSPN. Serum CysC was significantly associated with peroneal and ulnar compound muscle action potential amplitudes (p-value = 0.003 and p-value = 0.03, respectively) and peroneal and tibial motor nerve conduction velocities (p-value = 0.009 and p-value = 0.0003, respectively). Conclusions: Serum CysC levels > 0.9 mg/L are associated with DM-DSPN (86% sensitivity and 81% specificity), independently of HbA1c or GFR. Serum CysC is also associated with peroneal and ulnar compound muscle action potential amplitudes and peroneal and tibial motor nerve conduction velocities. Larger studies are needed to determine the role of CysC as a potential biomarker of DM-DSPN. Full article

Background/Objectives: The COVID-19 pandemic has emphasized the urgent need for non-invasive diagnostic strategies. While breath analysis has been widely investigated, sweat and sebum remain largely unexplored, despite being abundant, chemically diverse, and easily collected. This exploratory study presents a proof-of-concept workflow to evaluate their potential for infection biomarker discovery. Methods: Samples from 51 subjects were analyzed by headspace solid-phase microextraction coupled with gas chromatography and time-of-flight mass spectrometry (HS-SPME-GC/ToF-MS). Over 8000 untargeted volatile compounds were detected, reflecting the high complexity of these matrices. Results: Data refinement and chemometric modelling using principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) revealed robust separation between SARS-CoV-2-positive Patients and Controls. Classification accuracies consistently exceeded 95%, demonstrating the robust discriminative performance of the approach. Among the detected volatiles, 2-methylbenzenemethanol acetate emerged as the most informative compound, representing a potential biomarker candidate. Conclusions: This work shows that the sweat and sebum volatilome can be exploited for clinical applications. The workflow integrates non-invasive sampling, comprehensive chromatographic profiling, and advanced statistical modelling, representing a methodological contribution to analytical chemistry. Beyond COVID-19, the strategy provides a potential framework for volatile organic compound (VOC)-based diagnostics across different diseases and supports future development of sensor technologies for translation into healthcare practice. Full article

Background: Routine admission inflammatory and metabolic biomarkers have been proposed as adjunctive tools in mild traumatic brain injury (mTBI). However, their association with specific traumatic intracranial lesion types remains unclear. Methods: We conducted a prospective observational study including adult patients with isolated mTBI who underwent head computed tomography (CT) on admission. Admission laboratory parameters included the platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and glucose-to-potassium ratio (GPR). Two predefined endpoints were assessed. The first compared biomarker values between CT-positive and CT-negative patients. The second evaluated associations between biomarkers and individual intracranial lesion subtypes, including analyses restricted to isolated lesions. Results: A total of 125 patients were included, of whom 95 (76%) were CT-positive. No significant differences were observed between CT-positive and CT-negative patients for PLR (p = 0.793), GPR (p = 0.531), or SII (p = 0.291). In lesion-specific analyses including all intracranial injuries, subdural hematoma (SDH) was associated with higher GPR compared with patients without SDH (p = 0.016). In analyses restricted to patients with isolated lesions, SDH was associated with higher PLR (p = 0.018) and higher GPR (p = 0.015). No significant associations were observed between any biomarker and intraparenchymal hemorrhage, subarachnoid hemorrhage, or epidural hematoma (all p > 0.05). Patients with multiple intracranial injuries exhibited higher PLR (p = 0.012) and higher SII (p = 0.021) compared with those with isolated lesions. After correction for multiple comparisons, none of the observed associations remained statistically significant. Conclusions: These findings suggest that routine systemic biomarkers have limited global discriminatory value in mTBI. Exploratory lesion-specific associations with SDH did not remain significant after correction for multiple comparisons, underscoring the preliminary nature of these findings. Full article

Background: Atherosclerosis and its associated chronic inflammation of the arterial wall disrupt fatty acid metabolism, leading to changes in plasma fatty acid composition. These alterations can be used to improve disease diagnosis and risk stratification by the development and application of specific lipidomic indices. Objectives: The objectives of this study are to evaluate the performance of conventional fatty acid indices and enhance diagnostic efficiency in atherosclerosis by introducing novel index based on plasma PUFA n-6 and n-3 content (Omega-6/3 Balance Index, O6/3-BI), as well as the perspective SFA/MUFA ratio (stearic/oleic acid ratio, C18:0/C18:1n-9) and a logit function combining PUFA and SFA/MUFA biomarkers. Methods: Plasma fatty acids were quantified by LC-MS/MS in healthy controls (n = 50) and patients with carotid atherosclerosis (n = 52), stratified by atorvastatin, rosuvastatin, or no statin therapy. The conventional indices (the Omega-3 Status (EPA + DHA), AA/EPA, and the omega-6/omega-3 ratio), and pathway ratios (C18:0/C18:1n-9; and C20:4n-6/C22:4n-6), as well as the newly introduced PUFA index and combined PUFA-SFA/MUFA logit function, were calculated. Their diagnostic performance for distinguishing atherosclerosis was assessed by a receiver operating characteristic (ROC) analysis with the cross-validation and calculation of Cliff’s Δ effect size. Results: The conventional parameters demonstrated a poor to low discrimination ability of the atherosclerosis patients’ groups from healthy controls (area under the ROC curve, AUC 0.548–0.711). In statin-treated patients, these conventional markers lost significance. The newly introduced PUFA index and SFA/MUFA ratio demonstrated improved patients’ discrimination with AUC 0.734–0.780 for the former and strong predictive power with AUC 0.831–0.858 for the latter marker and maintained their diagnostic value under statin therapy. The most significant positive effect size was observed for the SFA/MUFA ratio with Cliff’s Δ = 0.67–0.71. The combined PUFA-SFA/MUFA logit function also demonstrated a strong predictive power with AUC = 0.880 (Cliff’s Δ = −0.76), outperforming any single index. Conclusions: The newly introduced lipidomic index based on the PUFA content, SFA/MUFA ratio, and a logit function combining PUFA-SFA/MUFA biomarkers demonstrated a substantially better discrimination of atherosclerosis-related fatty acid metabolic disturbances than conventional fatty acid biomarkers. Full article

Background/Objective: Sepsis remains a major cause of morbidity and mortality worldwide, making early risk stratification and prognosis critical. Vascular endothelial dysfunction is a hallmark of sepsis pathogenesis, with evidence suggesting that endothelial injury may occur early, preceding organ failure. Brachial flow-mediated dilation (FMD), a validated noninvasive ultrasound technique measuring endothelium-dependent vasodilation, serves as a surrogate marker of endothelial function, where lower FMD values reflect impaired function. This systematic review and meta-analysis aimed to evaluate the validity and quality of evidence on using FMD to measure vascular endothelial dysfunction in septic patients by comparing FMD (i) between septic patients and non-septic controls and (ii) between sepsis non-survivors and survivors. Methods: PubMed, Embase, Scopus, and Web of Science were searched until November 2024 for clinical studies assessing FMD in septic patients. A random-effects model was used for the meta-analysis, and quality of studies was assessed using the Newcastle–Ottawa Scale. Results: Eight studies were included, and seven underwent quantitative synthesis (385 septic patients, 106 non-survivors and 217 survivors). Compared with non-septic controls, septic patients demonstrated significantly lower FMD (pooled standardized mean difference (SMD) = −2.1617; 95% CI −3.8349 to −0.4885; p = 0.0113; I² = 98.2939%). Within the sepsis cohort, non-survivors showed significantly attenuated FMD compared to survivors (pooled SMD = −0.7003; 95% CI −1.1133 to −0.2873; p = 0.001; I² = 60.5593%). Conclusions: FMD shows potential as a surrogate marker of endothelial dysfunction for sepsis risk assessment, as evident by lower FMD in septic patients, particularly non-survivors. Full article

Programmed death-ligand 1 (PD-L1) biomarker testing in gastric cancer is required to identify patients suitable for immunotherapy. However, the PD-L1 testing landscape is complex, with various PD-L1 tests available and multiple algorithms that combine tumor and immune cell staining. To provide guidance on the best practices for PD-L1 testing in gastric cancer, we reviewed the literature and incorporated our extensive experience using the PD-L1 IHC PharmDx 22C3 and 28-8 assays and scoring with the combined positive score (CPS) algorithm. This review summarizes inter-reader agreement and PD-L1 assay concordance studies in gastric cancer, highlights practical challenges and pitfalls encountered in our own laboratory, and proposes solutions to address them. Accurate and consistent interpretation of PD-L1 CPS in gastric cancer is challenging, but can be improved with training, experience, and close attention to interpretation guidelines. Techniques are available that can optimize the automated staining of PharmDx PD-L1 assays using the Autostainer Link 48 to ensure consistent staining performance. The PD-L1 IHC PharmDx 22C3 and PD-L1 IHC PharmDx 28-8 assays show high concordance when used according to manufacturers’ guidelines. Full article

Objectives: Although angiopoietin-like 4 (ANGPTL4) is highly associated with glucose hemostasis and lipid metabolism, the relationships between the serum ANGPTL4 level, glucose status and hepatic steatosis remain unclear. Therefore, this study aimed to quantify the independent effects of glucose intolerance and hepatic steatosis on circulating ANGPTL4 concentrations. Methods: A total of 348 age- and sex-matched participants with normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and newly diagnosed diabetes (NDD) with or without hepatic steatosis were recruited for this cross-sectional study. Serum ANGPTL4 levels were measured, and multivariate linear regression analysis was used to evaluate the relationship between ANGPTL4, glycemic status and hepatic steatosis. Results: Compared with NGT, both IGT and NDD were associated with significantly higher serum ANGPTL4 concentrations, irrespective of hepatic steatosis status. Serum ANGPTL4 did not differ by the presence versus absence of hepatic steatosis. In multiple regression analysis, body mass index, homeostasis model assessment of insulin resistance, NGT vs. IGT, and NGT vs. NDD were independently associated with ANGPTL4 levels after adjustment for cardiovascular risk factors and adiponectin, whereas hepatic steatosis was not. Conclusions: Elevated serum ANGPTL4 concentrations were independently associated with prediabetes and diabetes, irrespective of hepatic steatosis. Full article

Extracellular Vesicle-associated microRNAs (EV-miRNAs) are emerging as pivotal regulators of corneal health and disease, holding exceptional promise for transforming both diagnostics and therapeutics. These vesicles carry distinct miRNA signatures in biofluids such as tears, offering a powerful, non-invasive approach for early detection, risk stratification, and dynamic monitoring of corneal disorders. In addition, EV-miRNAs act as key mediators of critical biological processes, including inflammation, fibrosis, and tissue repair. Consequently, they represent attractive therapeutic targets; for example, engineered EVs loaded with miRNA mimics or inhibitors can precisely modulate these pathways to promote regeneration and suppress disease progression. Yet, despite this considerable promise, the translation of EV-miRNA research into clinical practice remains constrained by several challenges. Topmost among these are the lack of standardized EV isolation methods, variability in miRNA quantification, and the pressing need for regulatory frameworks tailored to the complexity of these biological therapeutics. Addressing these barriers is essential to ensure reproducibility, scalability, and safety in clinical applications. Accordingly, this review synthesizes current knowledge on EV-miRNA profiles in corneal diseases, critically evaluates their diagnostic and therapeutic potential, and highlights strategies to overcome existing technical and regulatory limitations. Ultimately, the successful integration of EV-miRNA-based approaches into personalized medicine frameworks could revolutionize the management of corneal diseases and substantially improve patient outcomes. Full article

Background: Glioblastoma is an aggressive brain tumor that invariably recurs despite treatment, partly due to metabolic adaptations, including altered lipid metabolism. This study investigates plasma lipidomic profiles in patients with glioblastoma to explore their potential as a liquid biopsy for disease monitoring. Methods: Plasma samples were collected from 36 patients with histopathologically confirmed IDH wild-type glioblastoma at four treatment stages: pre-surgery (n = 36), post-surgery (n = 32), pre-radiation (n = 28), and post-radiation (n = 17). Untargeted lipidomics analysis was performed using liquid chromatography-high resolution mass spectrometry (LC-HR-MS/MS). Results: Plasma lipidomic signatures differed significantly across treatment stages. Specifically, the lipidomic profile prior to surgery was statistically distinct from those at subsequent stages, demonstrating an increased compound abundance of numerous lipids that are decreased at subsequent stages, including linoleic acid (fold-change 2.58, p = 4.21 × 10⁻¹¹), behenic acid (fold-change 2.09, p = 9.3 × 10⁻¹⁰), and linolenic acid (fold-change 4.44, p = 5.83 × 10⁻⁶). Random forest modeling could predict pre-surgical samples with 85.7% accuracy. Conclusions: Plasma lipidomics shows promise as a potential liquid biopsy approach for monitoring glioblastoma treatment but future studies will need to examine these findings in larger and well-controlled cohorts. Full article

Sepsis represents a life-threatening organ dysfunction caused by a dysregulated host response to infection, and is considered a medical emergency. Therefore, quick diagnosis and treatment are required in order to improve survivability. Currently, patient evaluation in sepsis is based on the Sequential Organ Failure Assessment (SOFA) score to determine the severity of the disease; however, novel biomarkers are also actively researched with the aim to develop quicker diagnostic tools and better therapy. Endothelin-1 is one of the most potent vasoconstrictors found in the human body and is involved in the pathophysiology of both sepsis and other conditions involving organs that make up the SOFA score. In this narrative review, we aimed to gather information of this peptide’s multiple effects and to help determine whether or not it could prove a valuable biomarker in the evaluation of patients with multi-organ dysfunction in sepsis. Full article

Background: Head and neck squamous cell carcinoma (HNSCC) is a prevalent malignancy with poor clinical outcomes. microRNA-7-5p (miR-7-5p) has been described as both a tumour suppressor and an oncomiR depending on the tissue context, but its role in HNSCC remains unclear. This study aimed to clarify the clinical significance and biological function of miR-7-5p in HNSCC by integrating data from multiple sources. Methods: A systematic review of the literature was conducted to identify studies analysing miRNA expression in human head and neck tissues. A meta-analysis of individual patient data from Gene Expression Omnibus (GEO), ArrayExpress, and The Cancer Genome Atlas (TCGA) was performed to assess miR-7-5p expression in tumours and normal tissues, and its associations with clinical parameters and prognostic outcomes. Bioinformatics analyses were used to predict miR-7-5p target genes, classify hub genes, and perform gene ontology enrichment analysis. MicroRNA in situ hybridisation (miRNA ISH) and real-time quantitative PCR (RT-qPCR) were conducted on tissue samples, HNSCC cell lines, and an in vitro model of oral oncogenesis to validate miR-7-5p expression patterns. Results: miR-7-5p was significantly upregulated in tumours compared to normal tissues and associated with larger tumour size, HPV-negative status, poor disease-specific survival, and shorter progression-free intervals. Bioinformatics analysis highlighted miR-7-5p target genes enriched in pathways related to cell growth, survival, and tumourigenesis. Despite evidence supporting the anti-cancer role of exogenous miR-7-5p in preclinical models, the observed endogenous upregulation in tumours suggests that miR-7-5p expression may represent a compensatory or stress-responsive mechanism during tumourigenesis, rather than acting as a primary oncogenic driver. Conclusions: This study provides new insights into the complex role of miR-7-5p in HNSCC, supporting its potential as both a biomarker and a therapeutic target. Understanding the context-specific functions of miR-7-5p is essential for its development as an RNA-based therapeutic in HNSCC. Full article

Background: Recently, the incidence of diabetes has increased. A rapid method for the diagnosis of prediabetes is needed. Although granulin levels are associated with obesity and insulin resistance, it remains unclear whether serum granulin concentration may serve as a biomarker of prediabetes and diabetes. Here, we examined the association between serum granulin and glycemic status in a clinical population. Methods: In total, 180 age- and sex-matched participants with normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and newly diagnosed diabetes (NDD) were recruited. Serum granulin levels were measured via an enzyme-linked immunosorbent assay. Multivariate linear regression analysis was performed to evaluate the relationships between the level of granulin and different glycemic statuses. The utility of the granulin concentration for diagnosis of prediabetes and diabetes was evaluated with a receiver operating characteristic (ROC) curve. Results: Serum granulin concentrations were significantly greater in the IFG, IGT and NDD groups than in the NGT group. Multiple linear regression analysis revealed that obesity and glycemic status were independently associated with granulin concentrations. The ROC curve analysis revealed an area under the curve of 0.781 (95% CI, 0.709–0.853; p < 0.001). Conclusions: An elevated serum granulin concentration has potential utility as a biomarker for screening prediabetes and diabetes. Full article

The cGAS-STING pathway initiates the core cascade of innate immune defense by recognizing pathogen-associated and self-derived abnormal nucleic acids, and key molecules (such as cGAS, STING, downstream IFN-β, IL-6, etc.) may serve as biomarkers in various diseases. The diverse mechanisms by which distinct nucleic acids activate this pathway provide novel insights for therapeutic strategies targeting infectious diseases, cancer, and autoimmune disorders. To prevent aberrant cGAS-STING pathway activation, cells employ multiple regulatory mechanisms, including restricting self-DNA recognition and terminating downstream signaling. Strategies to mitigate pathological activation involve reducing nucleic acid accumulation through nuclease degradation (e.g., of mitochondrial DNA or neutrophil extracellular traps, NETs) or directly inhibiting cGAS or STING. This review elucidates the molecular mechanism of nucleic acid-mediated regulation of cGAS-STING and its role in disease regulation. Full article

Elevated human epididymis protein 4 (HE4) levels decreased in patients with CF (pwCF) in response to CFTR-specific drugs and negatively correlated with FEV1% predicted values (ppFEV1). Objectives: Although elexacaftor/tezacaftor/ivacaftor (ETI, Kaftrio^®) demonstrates more substantial effectiveness than lumacaftor/ivacaftor (LUM/IVA, Orkambi^®) in pwCF, plasma biomarkers have not been used to compare treatment efficacy. Hence, our aim was to correlate the change in HE4 levels and the clinical effects of these CFTR modulators (CFTRm). Methods: Serum HE4 concentrations were measured in a total of 123 pwCF homozygous for the p.Phe508del-CFTR variant before treatment and 1–6 months after either ETI or LUM/IVA administration. A correlation between serum HE4 and ppFEV1 was assessed using the Spearman test. HE4 protein levels were also analyzed in the supernatants of p.Phe508del-CFTR CFBE 41o- cells before and after treatment with these CFTRm, and their direct effect on CFTR function was monitored by the whole-cell patch-clamp technique. Results: Serum HE4 levels were reduced below baseline after 3 months of either ETI or LUM/IVA (mean delta HE4: −38.5 vs. −18.5 pmol/L, respectively) when the mean change of ppFEV1 was 13.6 vs. 1.6% and remained decreased up to 6 months. A significant inverse correlation between HE4 and ppFEV1 was observed in both study cohorts (r = −0.537 and r = −0.575, respectively; p < 0.0001). In agreement with ex vivo results, the effect on p.Phe508del-CFTR was more pronounced by ETI than LUM/IVA in CFBE cells, showing a larger improvement in p.Phe508del-CFTR function and reductions in HE4 levels at 24 h. Conclusions: Serum HE4 negatively correlates with lung function improvement and monitors better drug efficacy in pwCF under ETI than LUM/IVA. Full article

Background/Objectives: Intrinsic biomarkers, such as serum vitamin D levels and the conjunctival ultraviolet autofluorescence (CUVAF) area, have been proposed to quantify sunlight exposure. Evidence suggests that reduced outdoor activity during the SARS-CoV-2 pandemic accelerated the progression of myopia; however, there is little information on the impact of such restrictions on vitamin D levels and CUVAF area in populations with myopia. This study aims to assess the association between serum vitamin D levels and conjunctival ultraviolet autofluorescence area (CUVAF) in young adults with myopia during and after the pandemic, as well as its relationship with sun exposure habits and the use of skin protection measures. Methods: A prospective observational study was carried out. A total of 59 students participated, 32 with a diagnosis of myopia and 27 controls, during SARS-CoV-2 pandemic. Two serological tests for total 25-hydroxy vitamin D (D2 + D3) (Calciferol) were taken, activity habits and sun exposure were identified using the Intermountain Live Well Institute tool, and CUVAF images were taken post-pandemic. Results: In the 59 participants, we observed similar vitamin D concentrations between the myopic and control groups during and after the pandemic. However, analysis of CUVAF areas after the pandemic revealed that myopes had significantly smaller areas compared to controls (p < 0.05). Conclusions: The study demonstrated that using vitamin D as a biomarker for outdoor activity requires additional investigation; the CUVAF biomarker showed a significant association with myopia. Full article

Background/Objectives: Borderline personality disorder (BPD) is a psychiatric disorder characterized by emotional instability, impulsive behavior, and impaired interpersonal relationships. It is associated with a high prevalence of childhood trauma and neurobiological changes. This study aimed to compare ophthalmologic parameters, namely, optic nerve sheath diameter, intraocular pressure, and dry eye, in patients with BPD with healthy controls and to investigate the relations between these parameters and childhood trauma. Methods: This study included 51 female patients with BPD between the ages of 18 and 35 years, who were not using psychotropic medication, and 51 healthy controls matched for age and educational level. Optic nerve sheath diameter, intraocular pressure, and tear break-up time were measured, and trauma history was evaluated using the Childhood Trauma Questionnaire-Short Form. Independent t-test and Pearson correlation analysis were used in statistical analyses. Results: Patients with BPD were found to have significantly higher mean optic nerve sheath diameter scores (left: 3.94 ± 0.43, right: 3.97 ± 0.47) compared with healthy controls (left: 3.76 ± 0.44, right: 3.78 ± 0.45) (p < 0.05). The groups showed no significant difference in intraocular pressure and dry eye parameters (p > 0.05). A significant positive correlation was noted between emotional abuse scores and the optic nerve sheath diameter of the left eye in patients with BPD (p < 0.05; r = 0.364). Conclusions: An increased optic nerve sheath diameter may be a potential peripheral biomarker reflecting chronic stress or changes in intracranial physiology in patients with BPD. This increase is particularly associated with a history of emotional abuse. Ophthalmological parameters may contribute to understanding the neurobiological basis of BPD and serve as peripheral biomarkers or indicators of neurobiological changes. Full article

Background: Septic arthritis is an orthopedic emergency. However, optimal biomarkers and diagnostic criteria remain unclear. The study aimed to evaluate the diagnostic performance of routinely used and novel biomarkers, including serum C-reactive protein (CRP), synovial white blood cells (WBC), pentraxin-3 (PTX3), interleukin-6 (IL-6), and presepsin, in distinguishing septic from non-septic arthritis. Methods: Thirty-one patients undergoing arthrocentesis were included. Patients were categorized into septic and non-septic arthritis groups. Synovial fluid and serum samples were analyzed for five biomarkers. Diagnostic performance was assessed by calculating the area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Results: Synovial WBC demonstrated the highest diagnostic performance among single biomarkers (AUC = 0.837, p = 0.012). Among novel biomarkers, PTX3 showed the highest accuracy and sensitivity. The serum CRP and synovial WBC combination yielded an AUC of 0.853, with 100% sensitivity, 68.0% specificity, 42.9% PPV, and 100% NPV. Adding all three novel biomarkers to this combination increased the AUC to 0.887 (p = 0.004), maintaining 100% sensitivity and NPV. When individually added, PTX3 achieved 100% sensitivity and NPV, while presepsin showed the highest specificity (96.0%), PPV (75.0%), and accuracy (87.1%). Conclusions: Serum CRP and synovial WBC remain essential biomarkers for diagnosing septic arthritis; however, combining them with PTX3, IL-6, and presepsin improved diagnostic accuracy. PTX3 is best suited for ruling out septic arthritis due to its high sensitivity and NPV, whereas presepsin is more useful for confirmation, given its specificity and PPV. These results support a tailored biomarker approach aligned with diagnostic intent. Full article

Background/objectives: Polycystic ovary syndrome (PCOS) and metabolic dysfunction-associated steatotic liver disease (MASLD) are common co-morbidities in women of reproductive age. PCOS is highly heterogeneous and is, therefore, divided into four phenotypes. MASLD leads to numerous systemic complications. Studies to date have shown an association between PCOS and MASLD. This study was designed to compare the FIB-4 score (based on age, alanine aminotransferase, aspartate aminotransferase and platelet count) and the results of shear wave elastography in assessing the risk of developing MASLD by patients with PCOS divided by phenotypes. Methods: The study enrolled 242 women age 18–35 years with PCOS diagnosed according to Rotterdam criteria, hospitalized at the Department of Gynaecological Endocrinology of the University Clinical Centre in Katowice. The study subjects were assigned to phenotypes A to D. Clinical and biochemical assessments were performed (including androgens and metabolic parameters), and the FIB-4 index was calculated. Liver fibrosis was evaluated by shear wave elastography. To balance the group sizes of phenotypes, oversampling with replacement was applied (PROC SURVEYSELECT, SAS), increasing the number of observations for phenotypes B, C, and D fivefold. Statistical analyses were performed based on data distribution (Shapiro–Wilk test), using ANOVA or the Kruskal–Wallis test with Dunn’s correction. Statistical significance was set at p < 0.05. Results: The FIB-4 score was the highest in phenotype B patients (0.50 ± 0.15), and the lowest in phenotypes A and C (0.42 ± 0.14). The highest rate of positive elastography findings was recorded in phenotype A patients (34.7%) and the lowest in phenotype C group (13.5%). Significant differences between the phenotypes were also found in terms of androgen levels, insulin, HOMA-IR, and the lipid profile. Among patients with positive elastography, the highest FIB-4 scores were recorded in phenotype C group (0.44 ± 0.06), but the differences between the phenotypes were not statistically significant. Conclusions: The FIB-4 score was the highest in phenotype B patients and differed significantly from phenotypes A, C and D. In the elastography exam, the fibrosis index was statistically significantly higher in phenotype A compared to other phenotypes. No correlation was detected between the FIB-4 index and positive elastography. The findings suggest that the FIB-4 index may be used for MASLD screening, but its usefulness as a predictor of eligibility for elastography requires more research. Full article

Background/Objectives: Frailty is a key determinant of outcomes in older adults with heart failure (HF). The free triiodothyronine/free thyroxine (FT₃/FT₄) ratio has emerged as a promising frailty biomarker that reflects metabolic and systemic resilience. This study investigates its association with frailty, nutrition, muscle strength, inflammation, and one-year mortality in very old patients with HF. Methods: In this longitudinal, single-center study, we enrolled 193 older outpatients (mean age, 86.5 ± 6.1 years; 56% women) recently discharged after acute HF. All patients underwent physical examination, blood testing, and comprehensive geriatric assessment, including handgrip strength (HGS). Participants were stratified by FT₃/FT₄ ratio (<1.7 vs. ≥1.7). Associations with the Clinical Frailty Scale (CFS) were examined using multivariable linear regression. Spearman’s correlations assessed relationships with inflammatory and nutritional biomarkers. Cox regression evaluated the association with all-cause mortality. Results: Patients with a low FT₃/FT₄ ratio (31.1%) exhibited greater frailty (CFS: median [IQR], 6 [2] vs. 4 [3]; p = 0.020), poorer nutritional status (Mini Nutritional Assessment: 10 [4] vs. 12 [3]; p = 0.008), and lower HGS (mean ± SD, 16.8 ± 3.7 kg vs. 20.3 ± 4.8 kg; p = 0.002). An inverse association was identified between the FT₃/FT₄ ratio and frailty (adjusted β = −0.09; p = 0.019). Individuals with low FT₃/FT₄ also showed elevated inflammatory markers and had more than double the one-year mortality rate compared to those with higher ratios [HR 2.32 (95% CI, 1.24–4.34; p = 0.007)]. Conclusions: In very old adults recently hospitalized for HF, a lower FT₃/FT₄ ratio was associated with frailty, malnutrition, inflammation, and increased mortality, supporting its potential role as a marker of biological vulnerability. Full article

Background/Objective: Neurofilament light chain (Nf-L), neurofilament heavy chain (Nf-H), and chitinase 3-like 1 (CHI3L1) are cerebrospinal fluid (CSF) biomarkers of neuroaxonal damage and inflammation in multiple sclerosis (MS). Their longitudinal response to disease-modifying therapies and association with clinical and radiological outcomes remain incompletely understood. The aim of this study is to evaluate the impact of interferon beta (IFN-β) therapy on CSF levels of Nf-L, Nf-H, and CHI3L1 in early relapsing–remitting MS (RRMS) and assess their association with long-term clinical outcomes and MRI activity. Methods: We conducted a prospective two-year observational study involving 14 treatment-naive RRMS patients who initiated IFN-β therapy. CSF levels of Nf-L, Nf-H, and CHI3L1 were measured at baseline and after two years. Clinical disability was assessed via the Expanded Disability Status Scale (EDSS) and by studying brain MRI activity. A 15-year clinical follow-up was performed for 12 patients. Results: Nf-L levels significantly decreased after two years of IFN-β treatment (p = 0.039), while CHI3L1 levels significantly increased (p = 0.001). Nf-H levels remained stable. Nf-L and CHI3L1 levels at baseline and follow-up correlated with relapse rate and long-term EDSS. Nf-H levels correlated with EDSS scores but not with relapse or MRI activity. A trend toward a positive correlation between increasing Nf-L levels and MRI activity was observed (p = 0.07). Conclusions: CSF biomarkers demonstrate differential responses to IFN-β therapy in early RRMS. Nf-L emerges as a sensitive biomarker of treatment response and disease activity, while CHI3L1 may reflect ongoing tissue remodeling and inflammation. These findings support the utility of CSF biomarker monitoring for personalized treatment strategies in MS. Full article