Serum Samples Research Articles

The components of arginine and methylarginine metabolism are indicative of altered kidney function in intrauterine growth-restricted neonates.

Intrauterine fetal growth restriction (IUGR) affects up to 10% of all pregnancies. Severe IUGR is associated with impaired kidney development, reduced nephron endowment, and chronic kidney disease later in life. Currently, no early predictive biomarker exists for detecting altered kidney function in neonates with IUGR. Because nephrons produce key enzymes for the metabolism of arginine and methylarginine components, we quantified and compared the concentrations of arginine and methylarginine metabolites between IUGR and non-IUGR neonates to identify potential biomarkers for the early detection of altered kidney function in IUGR neonates. Seventy-one IUGR and 123 non IUGR neonates were examined. Serum and Urine samples were obtained between 30 h and 5 days of life and between 5 and 70 days of life. Serum concentrations of creatinine, urea, symmetric and asymmetric-dimethylarginine metabolites (SDGV, SDMA, ADGV, and ADMA), guanidino-2-oxo-caproic acid (GOCA), citrulline, homocitrulline, arginine, and homoarginine were quantified using LC-MS/MS and standard clinical laboratory methods. Datasets were compared by Mann-Whitney--Wilcoxon or Chi-square tests for continuous and discrete parameters. P values were corrected for multiple comparisons using the Bonferroni method. After Bonferroni correction, we found that serum creatinine, urea, SDGV, ADGV, and GOCA levels were significantly lower in neonates with IUGR. Consequently, the ratios of SDGV/SDMA, ADGV/ADMA, and GOCA/homoarginine were significantly lower in IUGR neonates. Our study suggests that arginine and methylarginine are possible early biomarkers for detecting altered kidney function in IUGR neonates.

Rapid photothermal assay for ultrasensitive point-of-care detection of tumor markers based on a filter membrane.

Anultrasensitive photothermal assay was designed for point-of-care testing (POCT) of tumor markers based on a filter membrane. Firstly, Cu2-xSe was successfully encapsulated in liposome spheres with biotin on the surface and connected to carcinoembryonic antigen (CEA) aptamer with 3'end modified biotin by streptavidin. Secondly, the CEA antibody was successfully modified on the surface of the nitrocellulose membrane through simple incubation. Finally, the assay process was completed using a disposable syringe, and the temperature was recorded using a handheld infrared temperature detector. In the range 0-50 ng mL-1, the temperature change of the nitrocellulose membrane has a strong linear relationship with CEA concentration, and the detection limit is 0.097 ng mL-1. It is worth noting that the entire testing process can be easily performed in 10 min, much shorter than traditional clinical methods. In addition, this method was successfully applied tothe quantitative determinationof CEA levels in human serum samples with a recovery of 96.2-103.3%. This rapid assay can be performed by "one suction and one push" through a disposable syringe, which is simple to operate, and the excellent sensitivity reveals the great potential of the proposed strategy in the POCT of tumor biomarkers.

Electroactive Molecularly Imprinted Polymer Nanoparticles (eMIPs) for Label-free Detection of Glucose: Toward Wearable Monitoring.

The diagnosis of diabetes mellitus (DM) affecting 537 million adults worldwiderelies on invasive and costly enzymatic methods that have limited stability. Electroactive polypyrrole (PPy)-based molecularly imprinted polymer nanoparticles (eMIPs) have been developed that rival the affinity of enzymes whilst being low-cost, highly robust, and facile to produce. By drop-casting eMIPs onto low-cost disposable screen-printed electrodes (SPEs), sensors have been manufactured that can electrochemically detect glucose in a wide dynamic range (1 µm-10mm) with a limit of detection (LOD) of 26nm. The eMIPs sensors exhibit no cross reactivity to similar compoundsand negligible glucose binding tonon-imprinted polymeric nanoparticles (eNIPs). Measurements of serum samples of diabetic patients demonstrate excellent correlation (>0.93) between these eMIPs sensor and the current gold standard Roche blood analyzer test. Finally, the eMIPs sensors are highly durable and reproducible (storage >12 months), showcasing excellent robustness and thermal and chemical stability. Proof-of-application is provided via measuring glucose using these eMIPs sensor in a two-electrode configurationin spiked artificial interstitial fluid (AISF), highlighting its potential for non-invasive wearable monitoring. Due to the versatility of the eMIPs that can be adapted to virtually any target, this platform technology holds high promise for sustainable healthcare applications via providing rapid detection, low-cost, and inherent robustness.

Association between the third trimester maternal serum metabolome and child growth and development through the first year of life

Evidence suggests that maternal metabolome may be associated with child health outcomes. We analyzed the association between the maternal metabolome between 28–35 gestational weeks and child growth and development during the first year. A prospective cohort of 98 mother–child dyads was followed at birth, 1, 6, and 12 months. Maternal serum samples were collected for targeted LC–MS/MS analysis, which measured 132 metabolites. The child's growth and development were assessed at each time-point. Z-scores were calculated based on WHO growth standards, and the domains of development were assessed using the Ages and Stages Questionnaires (ASQ-3). Multiple linear mixed-effects models were performed and confounders were identified using a Diagram Acyclic Graph. The Benjamini–Hochberg correction was used for multiple comparison adjustments. We found a positive association between lysophosphatidylcholines (14:0; 16:0; 16:1; 17:0; 18:0; 18:1; 18:2; 20:4) with the z-score of weight-for-age, and lysophosphatidylcholines (14:0; 16:0; 16:1; 18:0) and taurine with the z-score of weight-for-length, and lysophosphatidylcholines (14:0; 16:0; 16:1; 17:0; 18:0; 18:1; 18:2; 20:4) and glycine with the z-score of BMI-for-age. The leucine, methionine, tryptophan, and valine were negatively associated with the fine motor skills domain. We observed an association between maternal metabolome and the growth and child's development throughout the first year.

Utility of melatonin on brain injury, synaptic transmission, and energy metabolism in rats with sepsis.

Melatonin is a powerful endogenous antioxidant hormone. Its healing effects on energy balance and neuronal damage associated with oxidative metabolism disorders have been reported in pathologic conditions. We aimed to determinate the utility of melatonin on neuronal damage, synaptic transmission, and energy balance in the brain tissue of rats with sepsis induced with LPS. Rats was divided into four groups such as control, LPS (20mg/kg i.p.), melatonin (10mg/kg i.p. × 3), and LPS + Melatonin (LPS + Mel). After 6h from the first injection, rats were decapitated, and also tissue and serum samples were taken. Lipid peroxidation and neuron-specific enolase (NSE) levels were determined from the serum in all group. High energy compounds, creatine, and creatine phosphate are measured by HPLC methods from the homogenized tissue. Counts of living neurons are marked with NeuN (neuronal nuclei), degenerated neurons are marked with S100-ß and synaptic vesicles transmission is analyzed with synaptophysin antibodies immunoreactivities. One-way ANOVA and post hoc Tukey tests were used to statistical analysis. In LPS group, AMP, ATP, creatine, and creatine phosphate levels were significantly decreased (p < 0.05), and also ADP levels were significantly increased compared with the other groups (p < 0.01). Living neurons counts were significantly decreased in LPS (p < 0.01), melatonin, and LPS + Melatonin (p < 0.05) groups compared with control. Degenerated neurons counts were increased in LPS group compared with control (p < 0.01) and also decreased in both of melatonin and LPS + Melatonin groups (p < 0.01). Synaptophysin immunoreactivity was decreased in LPS group compared with the other groups (p < 0.05). We observed that melatonin administration prevents neuronal damage, regulates energy metabolism, and protects synaptic vesicle proteins from sepsis-induced reduction.

Ameliorative Effect of Polypodium vulgare L. Rhizome on Anxiety and Depressive-Like Behaviors in Restraint-Subjected Mice: Involvement of Inflammatory, Oxidative and Apoptotic Pathways

Background: Developing drugs with higher efficacy and fewer side effects for psychological disorders has always been of interest. The rhizome of Polypodium vulgare L. (common polypody) has been used as a mood stabilizer in Persian medicine (PM). Objectives: The present study evaluates the anxiolytic and antidepressant effects of the hydroethanolic extract of common polypody rhizome (PEE) and the possible underlying mechanisms in mice subjected to chronic restraint stress (CRS). Methods: Sixty NMRI male mice were exposed to CRS and received either a vehicle, fluoxetine, or PEE (at doses of 250, 500, 1000, and 1500 mg/kg-1). The forced swim test (FST), tail suspension test (TST), open-field test (OFT), and elevated-plus maze (EPM) were conducted to evaluate depressive-like and anxiety-like behavior. Oxidative, inflammatory, and apoptotic markers, as well as brain-derived neurotrophic factor (BDNF), were measured in the prefrontal cortex (PFC) and hippocampus (HIP). Corticosterone levels were also assessed in serum samples. Results: Polypody rhizome increased the time spent in the central zone of the OFT, as well as the time spent and the number of entries into the open arms of the EPM, while it decreased the immobility time in the FST and TST. Administration of PEE caused a significant decline in serum levels of corticosterone, as well as tissue levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and malondialdehyde (MDA). Additionally, it increased superoxide dismutase (SOD) activity in the PFC and HIP. Polypody rhizome also significantly restored total antioxidant capacity (TAC), glutathione peroxidase (GPx) activity, and BDNF expression in the HIP. Moreover, Bcl-2 levels increased in the PFC, and Bax and caspase-3 expressions were downregulated in both regions with PEE administration. Conclusions: Polypody rhizome exerted anxiolytic and antidepressant effects in behavioral tests and reversed CRS-induced oxidative, inflammatory, and apoptotic alterations.

Label-free fluorescence turn-on detection of alkaline phosphatase activity using the calcein-Ce3+ complex.

This study introduces an innovative approach for the real-time and efficient detection of alkaline phosphatase (ALP) activity, using a calcein fluorescence probe and leveraging the static quenching properties of calcein fluorescence by Ce3+ metal ions. In this method, calcein serves as the signal element, with its fluorescence effectively preserved through energy transfer or charge transfer when coordinated with Ce3+. Conversely, ALP catalyzes the phosphopeptide substrate to generate a substantial amount of Pi, preventing calcein fluorescence quenching due to the higher affinity between Pi and Ce3+ compared with that between calcein and Ce3+. The fluorescence intensity ratio (F-F0/F0) exhibited excellent linearity, facilitating sensitive ALP detection. The proposed ALP detection method covers a range from 0 to 1.4mU/mL (R2 = 0.9942), with the limit of detection at 0.069mU/mL (S/N = 3). Additionally, this method was successfully applied for detecting ALP in serum samples and studying its inhibitors. This research introduces a novel clinical diagnosis approach for ALP sensing while broadening the potential applications of calcein.

Evaluation of the Fluorion HCV QNP v3.0 real-time PCR assay for quantifying HCV RNA in Moroccan patients: A comparative study with COBAS AmpliPrep/COBAS TaqMan HCV v2.0

PurposeHepatitis C Virus (HCV) RNA quantification is crucial for diagnosing and monitoring chronic HCV treatment. Cost-effective methods are crucial to ensure accessibility. This study evaluated the Fluorion HCV QNP v3.0 Real-Time PCR assay's effectiveness in EDTA-plasma and serum, comparing it with the COBAS AmpliPrep/COBAS TaqMan HCV v2.0 (CAP/CTM HCV v2.0) test. Methods105 matched pairs of EDTA-plasma and serum specimens (91 positive and 14 negative) from HCV infected Moroccan patients were analyzed using the Fluorion HCV QNP v3.0 assay and compared to the CAP/CTM HCV v2.0 test, being the reference method. ResultsThe values obtained by the Fluorion HCV QNP v3.0 in plasma were slightly higher than those in serum (3.94 ± 2.23 log10 IU/mL versus 3.91 ± 2.22 log10 IU/mL) and were both significantly lower than those quantified by the CAP/CTM HCV v2.0 assay (4.34 ± 2.28 log10 IU/mL; p < 0.001). High correlations were observed between the Fluorion HCV QNP v3.0 serum and CAP/CTM HCV v2.0 (R2 = 0.9433), the Fluorion HCV QNP v3.0 plasma and CAP/CTM HCV v2.0 (R2 = 0.949) and the Fluorion HCV QNP v3.0 serum and plasma (R2 = 0.9954). HCV RNA was detected in all tested genotypes by both assays. ConclusionThe Fluorion HCV QNP v3.0 assay demonstrated excellent performance in comparison with the CAP/CTM HCV v2.0 on both plasma and serum samples which can be used interchangeably for HCV quantification. The test was shown to be suitable for disease monitoring including all HCV genotypes.

Serologically Confirmed Human Leptospirosis in Colombia, 2015-2020.

Leptospirosis, a bacterial infection transmitted through contact with infected animals or contaminated water sources, imposes a substantial health burden in Colombia. Since 2007, the National Institute of Health (INS) has mandated the notification and confirmation of all suspected leptospirosis cases. This passive surveillance program employs the microscopic agglutination test (MAT) on serum samples to ascertain confirmed cases of leptospirosis infection. However, the absence of a robust surveillance system has hindered our comprehensive understanding of the morbidity, mortality, geographical distribution, species/serovars, and strains responsible for severe disease. Our study aimed to provide an epidemiological overview of MAT-confirmed human leptospirosis cases reported over 6 years (2015-2020) in Colombia. In addition, we offer insights into the status of leptospirosis in the country, focusing on risk factors and proposing potential improvements for diagnosis and disease management. During the 6-year surveillance period, the laboratory at the INS received 3,535 serum samples from suspected human leptospirosis cases, with 880 (25%) confirmed through MAT. The incidence of leptospirosis was calculated at 1.9 cases per 100,000 people, with a higher prevalence among men (82.1%). Furthermore, 54 (6.1%) deaths were confirmed as leptospirosis, and cases were documented across nearly all regions of Colombia. Our findings emphasize the urgent need to strengthen leptospirosis laboratory surveillance, implement effective prevention measures, and enhance diagnostic capabilities in Colombia. The analysis conducted in this study provides the groundwork for estimating the impact of leptospirosis and raises awareness of its significance in public health.

The Seraph 100® Microbind Affinity Blood Filter Does Not Alter Levels of Circulating or Mucosal Antibodies in Critical COVID-19 Patients

PURIFY-OBS-1 is an observational study evaluating the safety and efficacy of Seraph 100® Microbind Affinity Blood Filter (Seraph 100) use for COVID-19 patients with respiratory failure admitted to the intensive care unit (ICU). The Seraph 100 is a hemoperfusion device containing heparin-coated beads that can bind to, and reduce levels of, some circulating pathogens and inflammatory molecules. This study evaluated whether treatment with the Seraph 100 affected circulating and mucosal antibody levels in critically ill COVID-19 subjects. SARS-CoV-2 anti-spike and anti-nucleocapsid IgG and IgA levels in serum were evaluated at enrollment and on days 1, 4, 7, and 28 after Seraph 100 application, while anti-spike and nucleocapsid IgG, IgA, and secretory IgA levels in tracheal aspirates were evaluated at enrollment and on days 1, 2, 3, 7, and 28. Serum samples were also collected from the pre- and post-filter lines at 1 and 4 h following Seraph 100 application to evaluate the direct impact of the filter on circulating antibody levels. Treatment with the Seraph 100 did not alter the levels of circulating or mucosal antibodies in critically ill COVID-19 subjects admitted to the ICU.

Determination of Gb3 and Lyso-Gb3 in Fabry Disease-Affected Patients by LC-MRM/MS

Limited or absent activity of the enzyme α-galactosidase A (α-Gal A), due to mutation in the related gene on the X chromosome, leads to the development of a rare hereditary and genetic disease known as Fabry disease (FD). This pathology involves a progressive accumulation in various organs of the substrates of the enzyme e.g., globotriaosylceramide (Gb3) and its deacylated form, globotriaosylsphingosine (Lyso-Gb3), suggesting these molecules as biomarkers of Fabry disease. The present paper describes the development of an analytical strategy for the identification and quantification of Gb3 and Lyso-Gb3, in serum and blood samples by using liquid chromatography (LC) coupled to mass spectrometry in multiple reaction monitoring (MRM/MS) ion mode. The best experimental conditions were obtained by extracting the glycolipids with chloroform/methanol/H2O (2/1/0.3) and by separating them on a C4 column with a linear gradient (A: H2O with 2 mM ammonium formate. B: methanol with 1 mM ammonium formate, both acidified with 0.2% formic acid). The best transitions (a combination of precursor and fragment ions—m/z) were 786.8 m/z &gt; 268.3 m/z for Lyso-GB3, 1137.3 m/z &gt; 264.3 m/z for Gb3, 1039.3 m/z &gt; 264.4 m/z for N-heptadecanoyl-ceramide trihexoside, and 843.5 m/z &gt; 264.3 m/z for N-glycinated lyso-ceramide trihexoside, the latter being used as an internal standard. The developed method provided a reliable, fast, and effective procedure for direct measurements of GB3 and Lyso-GB3 in serum and blood for diagnosis of Fabry disease, suggesting this method as a complementary assay to the current enzymatic test. Therefore, this approach could open new insights into the clinical diagnostics of lysosomal storage disorders.

Performance evaluation of microfluidic microplate-based fluorescent ELISA for qualitative detection of SARS-CoV-2–specific IgG and IgM

We evaluated the diagnostic performance of newly developed microfluidic microplate-based fluorescent ELISA for anti-SARS-CoV-2 antibody detection: the Veri-Q opti COVID-19 IgG and IgM ELISAs (hereafter, “Opti IgG/M”; MiCo BioMed, Gyeonggi-do, Republic of Korea), in comparison with conventional ELISAs. A total of 270 serum samples were analyzed, among which 90 samples were serially obtained from 25 COVID-19 patients. Another 180 samples were collected from 180 SARS-CoV-2–negative individuals. As comparative assays, we used SCoV-2 Detect IgG/M ELISA (hereafter, “InBios IgG/M”; InBios, Seattle, WA, USA) and Veri-Q COVID-19 IgG/IgM ELISA (hereafter, “Veri-Q IgG/M”; MiCo BioMed). Compared with conventional ELISAs, the Opti IgG yielded 97.1–100.0% positive percent agreement, 95.2–98.0% negative percent agreement, 96.3–97.8% total percent agreement, and kappa values of 0.90–0.94. Between the Opti IgM and the InBios IgM, the values were 93.7%, 96.6%, 95.9%, and 0.89, respectively. For the Opti IgG, sensitivities for the samples collected from 0–7, 8–14, 15–21, and ≥ 22 days after symptom onset were 40.0, 58.3, 94.1, and 100.0%, respectively. The values for the Opti IgM were 30.0, 54.2, 88.2, and 80%, respectively. The diagnostic specificities of the Opti IgG and IgM were 99.4 and 97.2%, respectively. The microfluidic microplate-based fluorescent ELISAs showed comparable diagnostic performance to conventional ELISAs for detecting anti-SARS-CoV-2 antibodies. With the combination of high throughput, a simplified workflow, and the ability to analyze reduced volumes, this new technology has great potential for improving SARS-CoV-2 serologic testing.

Graphene-based field-effect transistor biosensor for prostate-specific antigen detection

The development of a graphene-based field-effect transistor (GFET) aptasensor for prostate-specific antigen (PSA) detection. We present the novel use of 1-pyrenebutyric acid N-hydroxysuccinimide ester (PBASE) to functionalize the graphene surface, enabling covalent bonding of amine-functionalized PSA-binding aptamers. Under optimized conditions, the shift of the GFET aptasensor’s Dirac point voltage exhibited a systematic variation with PSA concentrations. The sensor demonstrated a relatively wide linear dynamic range spanning from 100 fM to 100 nM, with a detection limit of 3.5 pM. Importantly, it displayed satisfactory specificity against potential interfering proteins and demonstrated good reproducibility and stability. Furthermore, we successfully applied the proposed method for the quantification of PSA in human serum samples, indicating its potential for bioanalysis and clinical diagnostics. The GFET aptasensor’s potential in medical diagnostics and personalized healthcare, positioning it as a promising tool for rapid and accurate biomarker detection.

The ARDS microenvironment enhances MSC-induced repair via VEGF in experimental acute lung inflammation

Clinical trials investigating the potential of mesenchymal stromal cells (MSCs) for the treatment of inflammatory diseases, such as acute respiratory distress syndrome (ARDS), have been disappointing; with less than 50% of patients responding to treatment. Licensed MSCs show enhanced therapeutic efficacy in response to cytokine-mediated activation signals. There are two distinct sub-phenotypes of ARDS: hypo- and hyper-inflammatory. We hypothesised that pre-licensing MSCs in a hyper-inflammatory ARDS environment would enhance their therapeutic efficacy in acute lung inflammation (ALI). Serum samples from ARDS patients were segregated into hypo- and hyper-inflammatory categories based on IL-6 levels. MSCs were licensed with pooled serum from hypo- or hyper-inflammatory ARDS patients or healthy serum controls. Our findings show that hyper-inflammatory ARDS pre-licensed MSC conditioned medium (MSC-CMHyper) led to a significant enrichment in tight junction expression and enhanced barrier integrity in lung epithelial cells in vitro and in vivo; in a VEGF-dependent manner. Importantly, while both MSC-CMHypo and MSC-CMHyper significantly reduced IL-6 and TNFα levels in the bronchoalveolar lavage fluid (BALF) of LPS-induced ALI mice, only MSC-CMHyper significantly reduced lung permeability and overall clinical outcomes including weight loss and clinical score. Thus the hypo- and hyper-inflammatory ARDS environment may differentially influence MSC cytoprotective and immunomodulatory functions.

Animal and organoid models to elucidate the anti-fibrotic effect of steroid on biliary atresia

PurposeWe performed animal and organoid study to evaluate the anti-fibrotic effect of steroid on biliary atresia (BA) and the underlying patho-mechanism.MethodsBA animal models were created by inoculation of mice on post-natal day 1 with rhesus rotavirus (RRV). They received either 20 µl phosphate-buffered saline (PBS) or steroid from day 21 to day 34. On day 34, their serum samples were collected for hormonal markers. Necrosis, fibrosis and CK 19 expression in the liver were evaluated. Liver organoids were developed and their morphology as well as bulk RNA sequencing data were analyzed.ResultsTwenty-four mice developed BA features after RRV injection and were equally divided into steroid and PBS groups. On day 34, the weight gain of steroid group increased significantly than PBS group (p < 0.0001). All mice in the PBS group developed liver fibrosis but only one mouse in the steroid group did. Serum bilirubin and liver parenchymal enzymes were significantly lower in steroid group. The morphology of liver organoids were different between the two groups. A total of 6359 differentially expressed genes were found between steroid group and PBS group.ConclusionBased on our findings obtained from RRV-induced BA animal and organoid models, steroid has the potential to mitigate liver fibrosis in BA.

Molecular genetic characterization of hepatitis B virus in blood donors from South Vietnam

The problem of transfusion safety preventing parenteral viral hepatitis transmission remains relevant. Viral hepatitis B (HB) is the most common viral infection transmitted through transfusion procedures. One of the natural phases of a chronic viral hepatitis B (CHB) course is occult hepatitis B infection (OBI) characterized by undetectable HBsAg level (regardless of other serological marker levels) along with detected hepatic HBV DNA as well as blood viral load ranging from extremely low to undetectable. In Vietnam, prevention of transfusion-based HBV transmission is focused on donor screening; it is still based solely on HBsAg serology. As such, OBI remains a potential threat to blood transfusion safety. Assessing hepatitis B virus (HBV) DNA is a reliable preventive measure against HBV transmission from HBsAg– donors, especially in highly endemic regions. The aim of our work was HBV identification and molecular genetic characterization in blood donors from South Vietnam. The study material was presented by 500 donor serum samples. Subjects were examined for HBV markers with qualitative detection of HBsAg, HBs IgG, and HBcore IgG. Amplification and subsequent HBV sequencing were performed using nested PCR with overlapping primer pairs jointly flanking the complete HBV genome (S, P, C, X genes). Full-size HBV genome nucleotide sequences were obtained for 58 samples. Among blood donors, taking into account HBsAg+ and HBsAg– samples, HBV DNA was detected in 11.6%, including 8.6% OBI. HBV phylogenetic analysis showed genotypes B and C. Vaccine escape mutations and mutations that contribute to disease progression were identified. Current screening in Vietnam is insufficient for eliminating the risk of transfusion-transmitted HBV infection. The major risk factor is OBI. PCR testing for HBV should be considered for blood donor screening.

A hydrogen sulfide photoelectrochemical sensor based on BiVO4/Fe2O3 heterojunction.

A BiVO4/Fe2O3 heterojunction for non-enzymatic photoelectrochemical (PEC) determination of hydrogen sulfide (H2S) is reported. The BiVO4/Fe2O3 heterojunction promoted the separation of photo-generated carriers, reduced electron-hole recombination, and thus improved electron collection and photocurrent. The proposed BiVO4/Fe2O3/FTO sensor exhibited a linear range of 1-500μM and a detection limit of 0.51 nMH2S. In addition, high selectivity, good reproducibility, and stability were obtained for H2S sensing. Thedetection of H2S in water and serum samples demonstrated its feasibility. This work provides a new strategy to detect and understand the bio-function of H2S in the biological environment.

Copper(II)-Tannic Acid@Cu with In Situ Grown Gold Nanoparticles as a Bifunctional Matrix for Facile Construction of Label-Free and Ultrasensitive Electrochemical cTnI Immunosensor.

Sensitive detection of cardiac troponin I (cTnI) is of great significance in the diagnosis of a fatal acute myocardial infarction. A redox-active nanocomposite of copper(II)-tannic acid@Cu (CuTA@Cu) was herein prepared on the surface of a glassy carbon electrode by electrochemical deposition of metallic copper combined with a metal stripping strategy. Then, HAuCl4 was in situ reduced to gold nanoparticles (AuNPs) by strong reductive catechol groups in the TA ligand. The AuNPs/CuTA@Cu composite was further utilized as a bifunctional matrix for the immobilization of the cTnI antibody (anti-cTnI), producing an electrochemical immunosensor. Electrochemical tests show that the immunoreaction between anti-cTnI and target cTnI can cause a significant reduction of the electrochemical signal of CuTA@Cu. It can be attributed to the insulating characteristic of the immunocomplex and its barrier effect to the electrolyte ion diffusion. From the signal changes of CuTA@Cu, cTnI can be analyzed in a wide range from 10 fg mL-1 to 10 ng mL-1, with an ultralow detection limit of 0.65 fg mL-1. The spiked recovery assays show that the immunosensor is reliable for cTnI determination in human serum samples, demonstrating its promising application in the early clinical diagnosis of myocardial infarction.

Acute Q fever in patients with an influenza-like illness in regional New South Wales, Australia.

Query (Q) fever is a zoonosis caused by the bacterium Coxiella burnetii typically presenting as an influenza-like illness (ILI) with or without hepatitis. The infection may be missed by clinicians in settings of low endemicity, as the presentation is clinically not specific, and there are many more common differential diagnoses for ILI including SARS-CoV-2 infection. Residual serum samples were retrospectively tested for Phase 1 and 2 Q fever-specific IgM, IgG, IgA antibodies by indirect immunofluorescence and C. burnetii DNA by polymerase chain reaction. They had not been previously tested for Q fever, originating from undiagnosed patients with probable ILI, aged 10-70 years and living in regional New South Wales, Australia. The results were compared with contemperaneous data on acute Q fever diagnostic tests which had been performed based on clinicians requests from a geographically similar population. Only one (0.2%) instance of missed acute Q fever was identified after testing samples from 542 eligible patients who had probable ILI between 2016-2023. Laboratory data showed that during the same period, 731 samples were tested for acute Q fever for clinician-initiated requests and of those 70 (9.6%) were positive. Probability of being diagnosed with Q fever after a clinician initiated request was similar regardless of the patients sex, age and the calendar year of sampling. In this sample, Q fever was most likely to be diagnosed via clinician requested testing rather than by testing of undiagnosed patients with an influenza like illness.

Serum biomarkers at disease onset for personalized therapy in multiple sclerosis.

The potential of combining serum neurofilament light chain (sNfL) and glial fibrillary acidic protein (sGFAP) levels to predict disability worsening in multiple sclerosis (MS) remains underexplored. We aimed to investigate whether sNfL and sGFAP values identify distinct subgroups of patients according to the risk of disability worsening and their response to disease-modifying treatments (DMTs). This multicentre study, conducted across thirteen European hospitals, spanned from July 15, 1994, to August 18, 2022, with follow-up until September 26, 2023. We enrolled MS patients who had serum samples collected within 12 months from disease onset and before initiating DMTs. Multivariable regression models were used to estimate the risk of relapse-associated worsening (RAW), progression independent of relapse activity (PIRA), and Expanded Disability Status Scale (EDSS) score of 3. Of the 725 patients included, median age was 34.2 years (IQR, 27.6-42.4), and 509 patients (70.2%) were female. Median follow-up duration was 6.43 years (IQR, 4.65-9.81). Higher sNfL values associated with an elevated risk of RAW (HR of 1.45; 95% CI 1.19-1.76; P < 0.001), PIRA (HR of 1.43; 95% CI 1.13-1.81; P = 0.003), and reaching an EDSS of 3 (HR of 1.55; 95% CI 1.29-1.85; P < 0.001). Moreover, higher sGFAP levels were linked to a higher risk of achieving an EDSS score of 3 (HR of 1.36; 95% CI 1.06-1.74; P = 0.02) and, in patients with low sNfL values, to PIRA (HR of 1.86; 95% CI 1.01-3.45; P = 0.04). We further examined the combined effect of sNfL and sGFAP levels. Patients with low sNfL and sGFAP values (NLGL) exhibited a low risk of all outcomes and served as reference. Untreated patients with high sNfL levels showed a higher risk of RAW, PIRA, and reaching an EDSS of 3. Injectable or oral DMTs reduced the risk of RAW in these patients but failed to mitigate the risk of PIRA and reaching an EDSS of 3. Conversely, high-efficacy DMTs counteracted the heightened risk of these outcomes, except for the risk of PIRA in patients with high sNfL and sGFAP levels. Patients with low sNfL and high sGFAP values (NLGH) showed an increased risk of PIRA and achieving an EDSS of 3, which remained unchanged with either high-efficacy or other DMTs. In conclusion, evaluating sNfL and sGFAP levels at disease onset in MS may identify distinct phenotypes associated with diverse immunological pathways of disability acquisition and therapeutic response.