Perioperative Change of High-Sensitive Cardiac Troponin I Concentration in Cats According to Three Different Anaesthesia Protocols.

BACKGROUND: Cardiac troponin I, a particular biomarker, is released into the bloodstream in response to myocardial injury. OBJECTIVES: To evaluate perioperative changes in high-sensitivity cardiac troponin I (hs-cTnI) concentration during ovariohysterectomy in cats undergoing three different anaesthesia protocols. METHODS:  Twenty-one female mixed-breed cats owned by clients aged (2.2 ± 0.7 years) and weight (3.2 ± 0.5 kg) were included in our study. The cats were divided into three groups: propofol-isoflurane (PI) group (n = 7), xylazine-ketamine (XK) group (n = 7) and xylazine-isoflurane (XI) group (n = 7). After pre-anaesthetic propofol (6 mg/kg IV) was administered to cats in Group PI, a mask was placed, and anaesthesia was maintained with 3.0% isoflurane in oxygen. Cats in Group XK underwent general anesthetization with xylazine hydrochloride (2 mg/kg IM) and, 10 min later, ketamine hydrochloride (10 mg/kg IM). Cats in Group XI were administered xylazine hydrochloride (2 mg/kg IM), and then anaesthesia (3.0% isoflurane and oxygen) was continued with a mask. Blood samples were collected from all cats; preoperatively and postoperatively at 0 and 12 h (Pre-, Post-0 h and Post-12 h, respectively). Serum hs-cTnI concentrations were measured with the Advia Centaur TnI-Ultra. RESULTS: In all 21 cats, hs-cTnI concentration increased at Post-0 h and 12 h measurement points compared to Pre-. In the XK group, hs-cTnI concentrations exhibited a significant increase at the Post-0 h (51.30 ng/L) and Post-12 h (157.70 ng/L) time points compared to Pre- (6.70 ng/L) (p < 0.05). CONCLUSIONS: The XK group increased the concentration of hs-cTnI more than other protocols. In the PI group, the increase in hs-cTnI concentrations at Post-0 and 12 h increased less than the other two groups (p < 0.05). The PI group was found to induce less myocardial damage.

Evaluation of Changes in Cardiac Troponin I Levels After Direct Current Cardioversion in Patients With Atrial Fibrillation.

INTRODUCTION: Direct current cardioversion (DCCV) of atrial fibrillation (AF) is a procedure used to restore normal heart rhythm. Cardiac biomarkers, such as cardiac troponin I (cTnI), are elevated in situations where injury-myocardial cell necrosis is induced. AIM: The aim of the present study was to investigate the change in cTnI levels, i.e., whether a myocardial injury is present, in patients with AF whose elective treatment was synchronized DCCV via a biphasic defibrillator. METHODS: The study sample included 59 patients who underwent synchronized DCCV for AF reversion. Measurement of cTnI before and after DCCV (one, three, and six hours) was performed by blood sampling and subsequent assay. RESULTS: It was observed that the value of cTnI did not change (<0.1 ng/mL) after DCCV at the measurement time points (one, three, and six hours). In addition, the value of cTnI remained constant (<0.1 ng/mL) in relation to the energy delivered, before DCCV and after DCCV (one, three, and six hours). However, it was found that there was a correlation between the outcome (AF reversion or not) and the energy used (joules). CONCLUSIONS: Synchronized DCCV with a biphasic defibrillator did not cause myocardial injury in any of the patients, as there was no change in cTnI values before and after DCCV.

Significance of detecting cardiac troponin I and creatine kinase MB in critically Ill children without primary cardiac illness.

Objective: To investigate the incidence of myocardial injury in children with critically ill children without primary cardiac disease and the association between elevated cardiac troponin I (cTnl) and creatine kinase MB (CK-MB) concentrations and disease progression and prognosis to guide early treatment. Methods: The serum cTnI and CK-MB concentrations of 292 children with critically ill children without primary cardiac disease in Yantai Yuhuangding Hospital between January 2021 and January 2024 were retrospectively analyzed within 24 h after entering the Pediatric Intensive Care Unit (PICU). The children were divided into normal and abnormal groups according to the myocardial marker results. The abnormal group was further divided into the cTnI-elevated, CK-MB-elevated, single-elevated (cTnI- or CK-MB-elevated) and double-elevated (cTnI- and CK-MB-elevated) groups. The differences in the clinical indicators and their relationships with prognosis for the groups were compared. Results: The incidence of myocardial injury among the critically ill children without primary cardiac disease was 55.1%. The incidence of myocardial injury in children with infectious diarrhea combined with moderate and severe dehydration reached 85.19%. The pediatric critical illness score; frequency of use of vasoactive drugs; hypotension, shock, heart failure, respiratory failure, and multiple organ dysfunction syndrome; and mortality indexes differed significantly for the normal and abnormal myocardial marker groups (P < 0.05). The single-elevated and normal groups only showed a difference in mortality (P < 0.017). The cTnI and CK-MB concentrations were negatively correlated with prognosis (P < 0.01). Conclusion: Myocardial injury, as evidenced by elevated cardiac biomarkers, is common in critically ill children without primary cardiac illness. cTnI and CK-MB are associated with outcomes. Shock, heart failure, and multiple organ dysfunction syndromes are independently associated with simultaneous elevations of CK-MB and cTnI concentrations. Further prospective studies are needed to elucidate the clinical utility of these biomarkers.

Case Report: Acute myocarditis in a patient with Duchenne muscular dystrophy.

Background: Cardiovascular complications are the leading cause of death among individuals with Duchenne muscular dystrophy (DMD). However, due to the difficulty in evaluating individuals with inactive DMD, acute myocardial injury may be overlooked. Case presentation: An 11-year-old boy with DMD presented to the emergency department with a 5-day history of persistent nasal congestion, runny nose, and cough. He was regularly taking prednisolone acetate, angiotensin-converting enzyme (ACE) inhibitors, and ß-blockers for suspected DMD-associated cardiomyopathy. Upon presentation, a substantially elevated cardiac troponin I (cTnI) level of 19.8 µg/L and abnormal electrocardiogram (ECG) results were detected. Further cardiac magnetic resonance imaging (CMR) showed myocardial inflammation with localized T2 hyperintensity from the basal to middle lateral and inferior walls, as well as late gadolinium enhancement (LGE) from the basal to apical inferior lateral walls, supporting a diagnosis of acute myocarditis. Subsequently, the patient showed clinical improvement in response to combination treatment with intravenous immunoglobulin, oral prednisolone acetate, potassium chloride sustained-release tablets, anti-heart failure medication, and broad-spectrum antibiotics. Conclusions: We report a rare case of acute myocarditis in a patient with DMD, potentially due to upper respiratory tract infection. This case highlights the importance of early myocarditis recognition and treatment in patients with DMD.

Perioperative changes in plasma cardiac troponin I concentration during mitral valvuloplasty for severe mitral regurgitation in dogs.

Background: Mitral valvuloplasty (MVP) is a surgical procedure for treating severe mitral regurgitation in dogs. Although MVP is considered highly invasive, the extent of myocardial injury, postoperative complications, and recovery has not been evaluated. Aim: This study examined the degree of MVP invasiveness, the extent of myocardial damage, postoperative complications, cardiomyocyte recovery, and timing of hospital discharge. Methods: Cardiac troponin I (cTnI) was used to investigate the myocardial damage caused by cardiac arrest associated with a surgical approach to the myocardium in 13 patients with MVP and five controls with patent ductus arteriosus (PDA) who underwent similar anesthesia and thoracotomy. Results: The level of cTnI peaked 1 day after surgery and was significantly higher in the MVP group (median, 19.90 ng/ml) than in the control group (median, 1.50 ng/ml p < 0.001). At day 7, the cTnI level was significantly higher in the MVP group (1.9 ng/ml) than in the control group (0.1 ng/ml) (p < 0.001), and recovery to the preoperative level took 10 days in the MVP group but returned to the preoperative level at day 7 in the control group. Although the mean arterial pressure of cardiopulmonary bypass (CPB) at the time of use was 42.92 mmHg, the peak cTnI levels in the two patients who exhibited a temporary decrease of 20 mmHg or less (46.03 ng/ml) were significantly higher than in the other 11 patients (19.70 ng/ml) (p < 0.05). Preoperative cTnI levels were correlated with the severity of postoperative complications (P = 0.03, F = 0.71). Conclusion: The results showed that MVP caused temporary greater myocardial tissue damage than thoracotomy, but postoperative recovery was smoother. A high preoperative cTnI level requires relatively more careful postoperative management, and measuring the level of cTnI over time after surgery can provide information about the extent of myocardial damage and recovery from surgery and help determine the time of discharge.

A Comparative Study of the Cardiovascular Effects of a Lower Dose of Heat-Stable Carbetocin Versus the Standard Dose in the Prevention of Postpartum Hemorrhage During Elective Cesarean Delivery: A Single-Blinded, Randomized, Parallel-Group Trial.

INTRODUCTION: Oxytocin is a uterotonic drug that acts on receptors in the myometrium, causing uterine contractions. However, oxytocin receptors are also present in other organs, including the myocardium. Heat-stable carbetocin, a long-acting analog of oxytocin, is also known to act on these oxytocin receptors. As carbetocin has a long half-life of 40 minutes, its duration of action on the myocardium may be relatively longer than that of oxytocin. Therefore, this study aimed to study the cardiovascular effects of using a lower dose of carbetocin (50 mcg) compared to the standard dose (100 mcg) during elective cesarean delivery. MATERIALS AND METHODS: A total of 212 full-term pregnant women were randomized into two groups: group I received 50 mcg of intravenous carbetocin, and group II received 100 mcg of intravenous carbetocin. Heart rate, blood pressure (BP), oxygen saturation, electrocardiogram changes, and pre- and postoperative (12 hours after cesarean delivery) high-sensitivity cardiac troponin I levels were compared between the groups. RESULTS: No statistically significant differences were observed between the groups with respect to heart rate, BP, electrocardiogram changes, or difference in pre- and postoperative high-sensitivity cardiac troponin I levels (p > 0.05). CONCLUSION: Carbetocin's cardiovascular effects were similar in both groups. None of the participants had adverse cardiovascular effects from the drug, and there were no differences in cardiovascular effects between the groups.

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.

An Electrochemical Biosensor for the Detection of Pulmonary Embolism and Myocardial Infarction.

Due to the clinical similarities between pulmonary embolism (PE) and myocardial infarction (MI), physicians often encounter challenges in promptly distinguishing between them, potentially missing the critical window for the correct emergency response. This paper presents a biosensor, termed the PEMI biosensor, which is designed for the identification and quantitative detection of pulmonary embolism or myocardial infarction. The surface of the working electrode of the PEMI biosensor was modified with graphene oxide and silk fibroin to immobilize the mixture of antibodies. Linear sweep voltammetry was employed to measure the current-to-potential mapping of analytes, with the calculated curvature serving as a judgment index. Experimental results showed that the curvature exhibited a linear correlation with the concentration of antigen FVIII, and a linear inverse correlation with the concentration of antigen cTnI. Given that FVIII and cTnI coexist in humans, the upper and lower limits were determined from the curvatures of a set of normal concentrations of FVIII and cTnI. An analyte with a curvature exceeding the upper limit can be identified as pulmonary embolism, while a curvature falling below the lower limit indicates myocardial infarction. Additionally, the further the curvature deviates from the upper or lower limits, the more severe the condition. The PEMI biosensor can serve as an effective detection platform for physicians.

Utility of Cardiac Troponin-I in the Prediction of In-Hospital Mortality of Patients With COVID-19: A Retrospective Cohort Study in Central India.

Laboratory tests have been used as prognostic markers in various diseases, especially those with infectious etiology, but the information on the role of biochemical parameters in the risk assessment of patients with COVID-19 is limited. We designed this retrospective cohort study to investigate the utility of troponin-I in predicting the in-hospital mortality of patients with COVID-19 admitted to our tertiary care hospital in central India. We strategically recorded the history, findings on physical examination, comorbid conditions, clinical diagnosis, results of the biochemical parameters, and adverse outcomes (in terms of survival or death) in order to assess the utility of troponin-I estimation done within the first 24 hours of admission in predicting the in-hospital mortality of patients with COVID-19. Appropriate statistical methods were used depending on the data generated to justify the aim of our study. P-values ​​less than 0.05 were considered significant. We observed a statistically higher (p=0.004) prevalence of mortality in the patients with higher troponin-I levels. We also observed a statistically significant association of other biochemical parameters with the mortality of these patients. Our study highlights the utility of troponin-I in predicting the in-hospital mortality of patients with COVID-19.

Specific reference interval for high-sensitivity cardiac troponin I among healthy children in Wuhan, China.

Background: Troponin (Tn) is of an important biomarker for the diagnosis and prognosis of myocardial injury and for evaluating the severity of cardiac involvement due to other systemic diseases in children. Unfortunately, high-sensitivity cardiac troponin I (hs-cTnI) specific reference intervals (RIs) are extremely limited. This study aimed to establish a preliminary pediatric hs-cTnI RI for newborns, children, and adolescents in Wuhan, China. Methods: A total of 1,355 healthy participants (1 day to 19 years) were recruited from a cross-sectional study implemented in Wuhan Children's Hospital from September 2022 to August 2023. Serum hs-cTnI levels were detected via the Mindray automated chemiluminescence immunoassay analyzer (CL-6000i). Specific serum hs-cTnI RIs were established according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. The RIs were defined by the nonparametric median (P50), and 2.5th, 97.5th [P50 (P2.5-P97.5)] intervals. Results: Of the 1,355 pediatric participants, serum hs-cTnI concentrations of 1,332 children were measured. The serum overall P50 and 95% interval range (P2.5-P97.5) of serum hs-cTnI was 0.41 (0.00, 44.31) ng/L. This was higher in males of 0.47 (0.00, 44.90) ng/L than in females of 0.36 (0.00, 44.17) ng/L (P<0.01). Age- and sex-specific differences in hs-cTnI levels were observed. The levels were highly variable in children under 1 year of age (especially in newborns), deriving a P50 (P2.5-P97.5) of 22.06 (1.04, 154.22) ng/L, and gradually narrowed and decreased with increasing age, with a markedly lower established P50 (P2.5-P97.5) of 0.36 (0.00, 2.16) ng/L. However, the levels began to increase slightly at the age of 9-12 years and reached a small peak at the age range of 15 to 18 years in males with 0.71 (0.03, 3.29) ng/L, while females were less affected by puberty. Sex- and age-specific RIs for hs-cTnI were established: 5 age-specific RIs in males, 1 day-1 month: 30.16 (8.67, 171.81) ng/L; >1-12 months: 13.20 (0.63, 61.91) ng/L; >1-15 years: 0.36 (0.00, 1.86) ng/L; >15-18 years: 0.71 (0.03, 3.29) ng/L; >18-19 years: 0.52 (0.00, 1.92) ng/L; and 4 age-specific RIs in females, 1 day-1 month: 43.93 (18.82, 146.38) ng/L; >1-12 months: 5.22 (0.92, 42.54) ng/L; >1-6 years: 0.54 (0.00, 2.74) ng/L; >6-19 years: 0.23 (0.00, 1.56) ng/L. Conclusions: This study preliminarily established age- and sex-specific serum hs-cTnI RIs using the Mindray CL-6000i system in healthy children in Wuhan, China.

Fouling-Free electrochemical strategy based on vertically-aligned peptide layer for cardiac troponin I sensitive detection in human serum.

BACKGROUND: Cardiac troponin I (CTnI) is demonstrated as one of the most promising disease biomarkers for early diagnosing acute myocardial infarction (AMI). To date, electrochemical immunosensors have been extensively studied in the field of cTnI determination. But highly accurate and sensitive cTnI detection by this method is still a challenge due to non-specific adsorption on electrode interfaces in complex human serum. As a result, it is necessary to develop an antifouling electrochemical immunosensor with high sensitivity for the detection of cTnI. RESULTS: In this work, an antifouling electrochemical immunosensor was constructed based on vertically-aligned peptide layer consisting of Au nanoparticles (AuNPs) and amphiphilic CEAK16 peptide (CEAK16@AuNPs) for sensitive and accurate detection of cTnI in human serum. The vertically-aligned CEAK16@AuNPs interface provided a stable hydration layer originated from attraction of water molecules by amino acids on the hydrophilic side of the CEAK16, which effectively reduced non-specific adsorption and enhanced electron transfer rate. The cTnI immunosensor possessed great analytical performance with a wide range from 1 fg mL-1 to 1 µg mL-1 and a low detection limit of 0.28 fg mL-1 (S/N = 3). Additionally, the proposed CEAK16@AuNPs sensing interface showed excellent long-term antifouling performance and electrochemical activity that preserved 80 % of the initial signal after 20-days exposure in human serum samples. Consequently, the cTnI immunosensor displayed excellent detection accuracy compared to clinical methods and owned good selectivity, stability and reproducibility. SIGNIFICANCE: The development of this strategy provides a versatile tool for accurate quantitative cTnI analysis in real human serum, thus helping to achieve early AMI diagnosis effectively and holding the promising potentials for other immunosensor in disease diagnosis.

Association of cigarette smoking with cardiometabolic risk factors: A cross-sectional study.

INTRODUCTION: Despite strong and consistent epidemiological evidence linking cigarette smoking to several cardiovascular diseases (CVDs), the association between smoking intensity and CVD risk factors remains unclear. This study aimed to explore the possible effects of cigarette smoking on cardiometabolic risk in healthy individuals. METHODS: This cross-sectional study was conducted between November 2022 and June 2023. Consecutive sampling was performed to include 160 healthy participants: 100 smokers with 60 males and 40 females; and 60 age- and sex-matched non-smokers with 36 males and 24 females. Blood samples were taken from each participant to assess their cardiometabolic function: lipid profile, von Willebrand factor (vWF), high-sensitivity cardiac troponin I (hs-cTnI), and fibrinogen levels; and liver function using an automated enzymatic method. In addition, blood sugar level, body mass index (BMI), and blood pressure were recorded. RESULTS: Smokers had significantly higher vWF functional activity and hs-cTnI but significantly lower albumin and total bilirubin levels than non-smokers (65.87 ± 19.07 vs 56.45 ± 6.59, respectively, p<0.001; 0.0382 ± 0.0077 vs 0.0147 ± 0.0105, respectively, p<0.001; and 4.63 ± 0.32 vs 4.74 ± 0.28, respectively, p=0.026). The number of cigarettes consumed daily was associated positively and significantly with plasma levels of low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, vWF functional activity, and hs-cTnI but were negatively associated with total bilirubin. Moreover, heavy smokers had a significantly higher BMI and waist-to-hip ratio among male smokers than non-smokers. CONCLUSIONS: Cigarette smoking was associated with increased dyslipidemia, BMI, and central obesity, in addition to higher vWF functional activity. Altogether, increased hs-cTnI levels in smokers indicate a higher susceptibility to CVD.

Liposome-embedded PtCu nanozymes for improved immunoassay of accurate myocardial infarction.

Herein, we developed a platinum-copper nano-enzyme-linked immunosorbent assay (NLISA) based split diagnostic platform for the ultrasensitive detection of cardiac troponin I (cTnI). The PtCu nanozyme synthesized by one-pot synthesis exhibited ultra-high peroxidase-like activity (35.17 U mg-1), which was about 4.5 times higher than that of the unmodified Pt nanozyme (8.83 U mg-1). Due to the efficient peroxidase-like activity of the copper-platinum complexed nanozyme, transduction and sequential amplification of cTnI biological signals were achieved in combination with a liposome-embedded amplification strategy. The encapsulation efficiency was calculated by introducing a liposomal bilayer model, which showed that the introduction of a single liposomal molecule could amplify the signal up to 870-fold, thus promising a high sensitivity test. Notably, the dynamic response of cTnI was in the range of 0.1-5000 pg mL-1 with an ultra-low detection limit (0.048 pg mL-1). The developed NLISA analysis system provides a new way to discover efficient and sensitive alternatives to ELISA kits, which can meet the practical needs of community healthcare testing conditions and rapid testing in hospitals.

Correlation between serum cardiac troponin I level and PDAI score in patients with pemphigus vulgaris.

Pemphigus vulgaris (PV) is a rare, yet serious autoimmune disorder primarily affecting the skin and mucous membranes. While the dermatological and mucosal aspects of PV are well-documented, the potential for systemic involvement, particularly cardiac complications, remains under-explored. This study aimed to investigate the serum cardiac troponin I (cTnI) level in patients with PV versus healthy controls. The relationship between serum cardiac troponin I (cTnI) levels and various demograpgics, clinical and laboratory characteristics in patients with PV was also dealt with. This cross-sectional study was conducted on 59 patients with pemphigus vulgaris and 59 age- and sex- matched healthy controls, visited at a tertiary care hospital from August 2021 to May 2023. After thorough history taking and physical examination, troponin level was measured by the ECL (Electrochemiluminescence) method. The correlation between serum cTnI level and various variables was evaluated using Pearson's correlation coefficient. The mean serum cardiac troponin I (cTnI) level in patient group was 0.104 ± 0.05 ng/mL, with a range of 0.01 to 0.25 ng/mL. Despite mean cTnI level in patients was greater than controls, this difference was not reach to the significance level (P value: 0.058). The analysis revealed a significant positive correlation (r = 0.52, p = 0.005310), suggesting that higher PDAI scores were associated with elevated cTnI level. The correlation between serum cardiac troponin I (cTnI) level and PDAI score, even without any clinical sign or risk factor for cardiovascular disease suggests a potential link between the severity of PV and subtle cardiac involvement, highlighting the importance of cardiac monitoring in these patients.

Diagnostic value of galectin-3, fractalkine, IL-6, miR-21 and cardiac troponin I in human ischemic cardiomyopathy.

OBJECTIVE: The primary objective of this study was to assess the diagnostic potential of galectin-3 (Gal-3), fractalkine (FKN), interleukin (IL)-6, microRNA(miR)-21, and cardiac troponin I (cTnI) in patients with ischemic cardiomyopathy (ICM). METHOD: A total of 78 ICM patients (Case group) and 80 healthy volunteers (Control group) admitted to our hospital for treatment or physical examination from Aug. 2018 to Feb. 2020 were included in the current study. The serum concentration of Gal-3, FKN, IL-6, miR-21, and plasma expression of cTnI of both groups were determined. The severity of ICM was classified using New York Heart Association (NYHA) scale. RESULTS: When compared with the control group, the case group had a significantly high blood concentration of Gal-3, FKN, IL-6, miR-21, and cTnI (P < 0.001). NYHA class II patients had lower blood levels of Gal-3, FKN, IL-6, miR-21, and cTnI than that in patients of NYHA class III and IV without statistical significance (P > 0.05). However, statistical significance could be achieved when comparing the above-analyzed markers in patients classified between class III and IV. Correlation analysis also revealed that serum levels of Gal-3, FKN, IL-6, miR-21, and cTnI were positively correlated with NYHA classification (R = 0.564, 0.621, 0.792, 0.981, P < 0.05). CONCLUSION: Our study revealed that up-regulated serum Gal-3, FKN, IL-6, miR-21, and cTnI levels were closely related to the progression of ICM. This association implies that these biomarkers have diagnostic potential, offering a promising avenue for early detection and monitoring of ICM progression.

A novel integrated lateral flow immunoassay platform for the detection of cardiac troponin I using hierarchical dendritic copper-nickel nanostructures.

Cardiac troponin I (cTnI) is a critical biomarker for the diagnosis of acute myocardial infarction (AMI). Herein, we report a novel integrated lateral flow immunoassay (LFIA) platform for highly sensitive point-of-care testing (POCT) of cTnI using hierarchical dendritic copper-nickel (HD-nanoCu-Ni) nanostructures. The electrodeposited HD-nanoCu-Ni film (∼22 µm thick) on an ITO-coated glass substrate exhibits superior capillary action and structural integrity. These properties enable efficient sample transport and antibody immobilization, making it a compelling alternative to conventional multi-component paper-based LFIA test strips, which are often plagued by structural fragility and susceptibility to moisture damage. The biofunctionalized HD-nanoCu-Ni substrates were laser-etched with lateral flow channels, including a sample loading/conjugate release zone, a test zone, and a control zone. Numerical simulations were used to further optimize the design of these channels to achieve optimal fluid flow and target capture. The HD-nanoCu-Ni LFIA device utilizes a fluorescence quenching based sandwich immunoassay format using antibody-labeled gold nanoparticles (AuNPs) as quenchers. Two different fluorescent materials, fluorescein isothiocyanate (FITC) and CdSe@ZnS quantum dots (QDs), were used as background fluorophores in the device. Upon the formation of a sandwich immunocomplex with cTnI on the HD-nanoCu-Ni device, introduced AuNPs led to the fluorescence quenching of the background fluorophores. The total assay time was approximately 15 min, demonstrating the rapid and efficient nature of the HD-nanoCu-Ni LFIA platform. For FITC, both inner filter effect (IFE) and fluorescence resonance energy transfer (FRET) contributed to the AuNP-mediated quenching. In the case of CdSe@ZnS QDs, IFE dominated the AuNP-induced quenching. Calibration curves were established based on the relationship between the fluorescence quenching intensity and cTnI concentration in human serum samples, ranging from 0.5 to 128 ng/mL. The limits of detection (LODs) were determined to be 0.27 ng/mL and 0.40 ng/mL for FITC and CdSe@ZnS QDs, respectively. A method comparison study using Passing-Bablok regression analysis on varying cTnI concentrations in human serum samples confirmed the equivalence of the HD-nanoCu-Ni LFIA platform to a commercial fluorescence cTnI LFIA assay kit, with no significant systematic or proportional bias observed.

A rapid and ultrasensitive cardiac troponin I aptasensor based on an ion-sensitive field-effect transistor with extended gate.

Acute myocardial infarction (AMI) is a life-threatening disease with a short course and a high mortality rate. However, it is still a great challenge to achieve the on-site diagnosis of this disease within minutes, meaning there is an urgent need to develop an efficient technology for realizing the rapid diagnosis and early warning of AMI in clinical emergencies. In this study, an ultrasensitive electrochemical aptasensor based on an extended-gate ion-sensitive field-effect transistor (EGISFET) was designed to achieve the quantitative assay of cardiac troponin I (cTnI), which is a highly sensitive and specific biomarker of AMI, within only 5 min. The EGISFET exhibits extremely high detection sensitivity due to its separated structure with a large sensing area and the surface-modified Prussian blue-gold nanoparticles (PB-AuNPs) composite, which serves as a signal magnifier and DNA loading platform for good electrocatalytic ability with a large specific area. Additionally, a target-induced strand-release strategy is proposed to shorten the recognition time of cTnI using a particular DNA strand. Under optimal conditions, the as-prepared aptasensor exhibits a wide linear range of 1-1000 pg/mL, an ultralow detection limit of 0.3 pg/mL, and reliable detection results in real serum samples. It is highly anticipated that this EGISFET-based aptasensor will have broad applications in the early warning and rapid diagnosis of AMI and other acute diseases in emergency treatment.

High-performance assaying cardiac troponin I using Bi-doped tin-based heterojunction in photoelectrochemical biosensing with the quencher of yolk-shell nanostructure.

Cardiac troponin I (cTnI), a protein regulating myocardial contraction, stands the premier biomarker for diagnosing acute myocardial infarction and stratifying heart disease risk. Photoelectrochemical (PEC) biosensing combines traditional PEC analysis with high bioconjugation specificity, rendering a prospective avenue for disease biomarker analysis. However, the performance of sensors often falls short due to inadequate photoelectric materials. Hence, designing heterojunctions with proper band alignment, effective transport and separation of photogenerated carriers is highly expected for PEC sensors. Meanwhile, doping as a synergistic strategy to tune the energy band edges and improve carrier transport in heterojunctions, can also enhance the sensing performance. In this work, bismuth-doped tin oxide and tin disulfide heterojunction (Bi-SnOS) was prepared via a simple one-step hydrothermal method and utilized as a highly sensitive platform. Integrating copper sulfide-coated nano-gold (Au@CuS), a yolk-shell shaped nanocomposites, as the double quenching probe, an excellent PEC biosensor was fabricated to assay cTnI via sandwich immunorecognition. Under optimal conditions, the proposed biosensor displayed a high-performance for cTnI in the range from 0.1 pg/mL to 5.0 ng/mL with a low detection limit (44.7 fg/mL, 3σ). The strong photocurrent response, high stability and suitable selectivity point out that the synergistic effect between heterojunction and doping provides a promising prospect for the design of new PEC materials.

Increased cTnI Predicts Early Death in Patients with Severe Fever with Thrombocytopenia: A Multicenter Study in North China.

Background: Myocardial injury is common in severe fever with thrombocytopenia syndrome (SFTS) patients. Currently, research on the prognostic value of cardiac troponin I (cTnI) for predicting the mortality of SFTS patients, especially death within 7 days is limited. Methods: Between May 2011 and October 2022, clinical and laboratory data on admission of consecutive SFTS cases were collected from six medical centres in China. The clinical endpoint was in-hospital all-cause death within seven days. Risk factors of myocardial injury and death were analysed using multivariable regression models. Prognostic models were established using Cox regression and performance of indicators was evaluated in terms of calibration, discrimination. Results: A total of 1379 laboratory-confirmed patients were enrolled, in which 686 subjects were included for analysis. The median age was 66 years, with 48.1% of male. Eighty-seven patients died within seven days and 396 patients diagnosed with myocardial injury during hospitalization. Non-survivors had significant higher levels of cardiac indices than survivors, including cTnI, aspartic transaminase (AST) and lactate dehydrogenase (LDH). Elevated levels of cTnI (HR = 1.058, 95% CI:1.032-1.085), AST (HR = 1.191, 95% CI:1.150-1.234) and LDH (HR = 1.019, 95% CI:1.009-1.029) predicted risk of early in-hospital mortality. cTnI model performed best, with area under curve of 0.850 (0.774-0.926) and concordance index of 0.842, respectively. Statistical differences were found between high and low levels of cTnI for mortality (P<0.001) using 0.35 ng/mL as the optimal cut-off. Conclusion: The risk of early in-hospital death can be predicted by cTnI. Clinical doctors should remind vigilant concerning the elevation of cardiac enzyme as soon as possible.

The Utility of Troponin Dynamics in Influenza Myopericarditis: A Literature Review.

Influenza, typically recognized as a respiratory ailment, can manifest severe cardiac complications, notably, myocarditis and pericarditis, with potential fatal outcomes. Interestingly, influenza B demonstrates a reduced occurrence of troponin I elevation despite the risk of cardiac issues, such as isolated pericarditis. Interpreting the absence of troponin elevation as an indication of no cardiac involvement in cases of influenza B-related pericarditis may be contributing to poorer clinical outcomes. This trend may stem from the cellular tropism and unique affinity of certain influenza strains for pericardial cells rather than myocardiocytes. A thorough grasp of troponin dynamics in influenza is pivotal for customizing approaches aimed at improving clinical outcomes in myopericarditis cases.