The Effect of a Subsequent Dose of Dexmedetomidine or Other Sedatives following an Initial Dose of Dexmedetomidine on Electrolytes, Acid-Base Balance, Creatinine, Glucose, and Cardiac Troponin I in Cats: Part II.

The administered dose of dexmedetomidine may occasionally fail to produce the anticipated sedative effects. Therefore, a subsequent dose or administration of another sedative may enhance sedation; however, patient safety may be affected. The safety of seven different drugs administered at the following time point after an insufficient dose of dexmedetomidine was evaluated in a crossover, blind, experimental study that included six healthy adult cats. All cats received an initial dose of dexmedetomidine and a subsequent dose of either dexmedetomidine (Group DD), NS 0.9% (DC), tramadol (DT), butorphanol (DBT), buprenorphine (DBP), ketamine (DK), or midazolam (DM). Animal safety was assessed using repeated blood gas analysis and measurement of electrolytes, glucose, cardiac troponin I, and creatinine to evaluate cardiac, respiratory, and renal function. The median values of creatinine, cardiac troponin I, pH, partial pressure of carbon dioxide, potassium, and sodium did not change significantly throughout the study. Heart rate was significantly decreased in all groups after administration of the drug combinations, except for in the DK group. Respiratory rate decreased significantly after administration of the initial dose of dexmedetomidine and in the DBP and DM groups. The partial pressure of oxygen, although normal, decreased significantly after the administration of dexmedetomidine, whereas the median concentration of glucose increased significantly following the administration of dexmedetomidine. The results of our study suggest that the drug combinations used did not alter the blood parameters above normal limits, while cardiac and renal function were not compromised. Therefore, a safe level of sedation was achieved. However, the administration of dexmedetomidine reduced the partial pressure of oxygen; thus, oxygen supplementation during sedation may be advantageous. Additionally, the increase in glucose concentration indicates that dexmedetomidine should not be used in cats with hyperglycaemia, whereas the decrease in haematocrit suggests that dexmedetomidine is not recommended in anaemic cats.

Myocardial injury in dogs: a retrospective analysis on etiological, echocardiographic, electrocardiographic, therapeutic, and outcome findings in 102 cases.

INTRODUCTION: In dogs, myocardial injury (MI) is a poorly characterized clinical entity; therefore, this study aimed to provide a detailed description of dogs affected by this condition. ANIMALS, MATERIALS, AND METHODS: Dogs diagnosed with MI according to the concentration of cardiac troponin I (cTnI) were retrospectively searched. Signalment, diagnostic, therapeutic, and outcome data were retrieved. Dogs were divided into six echocardiographic (dilated cardiomyopathy phenotype; hypertrophic cardiomyopathy phenotype; hypertrophic cardiomyopathy phenotype with systolic dysfunction; abnormal echogenicity only; endocarditis; and no echocardiographic abnormalities suggestive of MI), four electrocardiographic (abnormalities of impulse formation; abnormalities of impulse conduction; abnormalities of ventricular repolarization; and no electrocardiographic abnormalities suggestive of MI), and nine etiological (infective; inflammatory; neoplastic; metabolic; toxic; nutritional; immune-mediated; traumatic/mechanical; and unknown) categories. Statistical analysis was performed to compare cTnI values among different categories and analyze survival. RESULTS: One hundred two dogs were included. The median cTnI value was 3.71 ng/mL (0.2-180 ng/mL). Echocardiographic and electrocardiographic abnormalities were documented in 86 of 102 and 89 of 102 dogs, respectively. Among echocardiographic and electrocardiographic categories, the dilated cardiomyopathy phenotype (n = 52) and abnormalities of impulse formation (n = 67) were overrepresented, respectively. Among dogs in which a suspected etiological trigger was identified (68/102), the infective category was overrepresented (n = 20). Among dogs belonging to different echocardiographic, electrocardiographic, and etiological categories, cTnI did not differ significantly. The median survival time was 603 days; only eight of 102 dogs died due to MI. CONCLUSIONS: Dogs with MI often have an identifiable suspected trigger, show various echocardiographic and electrocardiographic abnormalities, and frequently survive to MI-related complications.

Comparison Between the Protective Effect of Isoflurane and Propofol on Myocardium During Coronary Artery Bypass Grafting: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

OBJECTIVE: Intravenous non-volatile anaesthetics like propofol are commonly used in cardiac surgeries across several countries. Volatile anaesthetics like isoflurane may help in protecting the myocardium and minimize ischaemia-reperfusion injury. Hence, we did this review to compare the cardioprotective effect of isoflurane and propofol among patients undergoing coronary artery bypass grafting (CABG). METHODS: We conducted a search in the databases Medical Literature Analysis and Retrieval System Online (or MEDLINE), Embase, PubMed Central®, ScienceDirect, Google Scholar, and Cochrane Library from inception until April 2021. We carried out a meta-analysis with random-effects model and reported pooled risk ratio (RR) or standardized mean difference (SMD) with 95% confidence interval (CI) depending on the type of outcome. RESULTS: We analysed 13 studies including 808 participants. Almost all were low-quality studies. For cardiac index, the pooled SMD was 0.14 (95% CI: -0.22 to 0.50); for cardiac troponin I, pooled SMD was 0.10 (95% CI: -0.28 to 0.48). For mortality, the RR was 3.00 (95% CI: 0.32 to 28.43); for MI, pooled RR was 1.58 (95% CI: 0.59 to 4.20); and for inotropic drug use, pooled RR was 1.04 (95% CI: 0.90 to 1.21). For length of intensive care unit stay, the pooled SMD was 0.13 (95% CI: -0.29 to 0.55), while pooled SMD for mechanical ventilation time was -0.02 (95% CI: -0.54 to 0.51). CONCLUSION: Isoflurane did not have significant cardioprotective effect compared to propofol following CABG. Hence, the anaesthetists need to check some viable alternatives to manage these patients and reduce the rate of postoperative complications.

Visual and quantitative lateral flow immunoassay based on Au@PS SERS tags for multiplex cardiac biomarkers.

Rapid and sensitive detection of multiple biomarkers by lateral flow immunoassay (LFIA) remains challenging for signal amplification for commonly used nanotags. Herein, we report a novel LFIA strip for visual and highly sensitive analysis of two cardiac biomarkers based on functionalized gold nanoparticles @ polystyrene microsphere (Au@PS）microcavity as surface-enhanced Raman scattering (SERS) tags. Antibody-modified Au@PS was designed as a SERS label. The evanescent waves propagating along the surface of the PS microcavity and the localized surface plasmons of the gold nanoparticles were coupled to enhance the light-matter interaction synergistically for Raman signal enhancement. In this strategy, the proposed Au@PS SERS tags-based LFIA was carried out to quantify the content of the heart failure and infarct biomarkers synchronously within 15 min and get the limits of detection of 1 pg/mL and 10 pg/mL for cardiac troponin I (cTnI) and N-terminal natriuretic peptide precursor (NT-proBNP), respectively. The results demonstrated 10-20 folds more sensitivity than that of the standard colloidal gold strip and fluorescent strip for the same biomarkers. This novel quantitative LFIA shows promise as a high-sensitive and visual sensing method for relevant clinical and forensic analysis.

Relationship between high sensitivity troponin I and clinical outcomes in non-acute coronary syndrome (non-ACS) acute heart failure patients - a one-year follow-up study.

OBJECTIVE: The primary objective of the study was to investigate the correlation between high-sensitivity troponin I (hsTropI) levels during hospitalization and the prognostic outcome in patients with non-acute coronary syndrome (non-ACS) acute heart failure, over a follow-up period of one year. The secondary objective was to assess and characterize acute heart failure during index hospitalization. METHODS: High sensitivity troponin I value was noted both at the time of admission and discharge. The correlation of admission hsTropI along with other parameters and risk factors with in-hospital mortality was studied. Patients of index hospitalization after discharge were followed up for one year and the composite endpoint of cardiovascular death or re-hospitalization for heart failure was noted. The correlation between admission and discharge hsTropI values with the composite endpoint was then analyzed. RESULTS: Out of 350 patients, 38 (10.8 %) patients died during index hospitalization while 142 patients (46 %) developed composite outcomes during follow-up. Age, previous history of heart failure, atrial fibrillation, low left ventricular ejection fraction, systolic blood pressure, and high values of hsTropI above 99th percentiles were independent in-hospital mortality predictors. The value of hsTropI at the time of admission was not associated with poor composite outcome during follow-up. However, patients who showed an increasing trend of hsTropI value at the time of discharge were found to have a significant increase in the composite outcome. CONCLUSION: High-sensitivity troponin I is a valuable biomarker that can predict in-hospital mortality and long-term follow-up outcomes in patients with acute heart failure. It plays a crucial role in developing improved strategies for heart failure surveillance and management in the community.

An unusual etiology in an 8-year-old girl with chest pain and elevated troponin-I.

Acute post-streptococcal glomerulonephritis (APSGN) is the most common glomerulonephritis of childhood, and clinical presentation can vary widely. This case report presents an atypical manifestation of APSGN in an 8-year-old female patient with pleuritic chest pain and elevated troponin-I, despite lacking classical kidney symptoms. Imaging studies showed cardiomegaly and interstitial lung opacities. Further investigations revealed hematuria and proteinuria, and the diagnosis was confirmed through elevated antistreptolysin-O (ASO) titers and low complement 3 (C3) levels. The patient was successfully managed with fluid restriction, diuretics, and antihypertensives, resulting in the resolution of symptoms and normalization of laboratory values. This case highlights the significance of recognizing atypical manifestations of APSGN for ensuring prompt diagnosis and proper management in the pediatric population.

Surface plasmon resonance biosensors for early troponin detection.

Acute myocardial infarction (AMI) is one of the life-threatening causes that decrease blood flow to the heart, leading to increased mortality and related complications. Recently, the measure of blood concentration of cardiac biomarkers has been suggested to overcome the limitations of electrocardiography (ECG) analyses for early diagnosis of this disease. Troponins, especially cardiac troponin I and cardiac troponin T, with high sensitivity and specificity, are considered the gold standards in myocardial diagnosis. Recently, the use of new biosensors such as surface plasmon resonance (SPR) for early detection of these biomarkers has been greatly appreciated. Due to the rapid, sensitive, real-time, and label-free detection of SPR-based biosensors, they can be applied for selective and nonspecific absorption that is intended to be used as an in situ cardiac biosensor. Here, we exclusively discussed the updated developments of these valuable predictors for the possible occurrence of AMI detected by SPR.

A cost-effectiveness evaluation of a high-sensitivity troponin I guided voluntary cardiovascular risk assessment program for asymptomatic women in Croatia.

Background: To estimate the effectiveness and cost-effectiveness of a high-sensitivity troponin I (hsTnI) guided cardiovascular risk assessment program in women in Croatia. Methods: An observational study of a voluntary program for cardiovascular disease (CVD) risk assessment in women aged above 45 years with no specific symptoms, no confirmed or known coronary artery disease was conducted (WHP). Participants were stratified into three categories according to their hsTnI level. Subjects in the moderate or high-risk class were referred to cardiac work-up and invasive cardiovascular investigation as appropriate. Study information were applied to a discrete-event simulation model to estimate the cost-effectiveness of WHP against current practice. The number of CVD events and deaths, costs, and quality-adjusted life years (QALY) were assessed over 10 years from a societal perspective. Results: Of 1034 women who participated in the program, 921 (89.1%), 100 (9.7%), and 13 (1.3%) subjects fall into the low, moderate, and high-risk class. Of 26 women referred for angiography, significant coronary artery disease (CAD) was diagnosed in 12 women (46.1%). WHP gained 15.8 (95%CI 12.8; 17.2) QALYs per 1000 subjects, increased costs by 490€ (95%CI 487; 500), decreased CVD-related mortality by 40%. At a willingness-to-pay threshold of 45,000 €/QALY, WHP was cost-effective with a probability of 90%. Model results were most sensitive to utility weights and cost of medical prevention. Conclusions: Assessing the cardiovascular risk in asymptomatic women with hsTnI and guiding those at higher risk to further cardiac testing, identified individuals with CAD, could reduce CVD related burden, and would be cost-effective.

Dual-Encoded Affinity Microbead Signature Combinatorial Profiling for Acute Myocardial Infarction High-Sensitivity Diagnosis.

The early diagnosis of acute myocardial infarction (AMI) is dependent on the combined feedback of multiple cardiac biomarkers. However, it remains challenging to precisely detect multicardiac biomarkers in complex blood early due to the lack of sensitive and specific diagnostic indicators and the low abundance and small size of associated biomarkers with high specificity (such as microRNAs). To make matters worse, spectral overlap significantly limits the multiplex analysis of cardiac biomarkers by fluorescent probes, leading to bias in the diagnosis of myocardial infarction. Herein, we developed a method for simultaneous detection of miRNAs and protein biomarkers using size- and color-coded microbeads that carry signature for target capture. We also constructed a microfluidic chip with different spacer arrays that segregate these microbeads in different chip regions according to their size to produce signature signals, indicating the level of different biomarkers. The signals on the microbeads were hugely amplified by catalytic hairpin assembly and rolling circle amplification. Notably, this strategy enables the simultaneous and in situ sensitive profiling of six kinds of biomarkers via adding two different fluorescent labels, removing the limitations of spectral overlap. We envision that the strategy has great potential for application in clinical diagnosis for AMI.

l-Cysteine-Tuned the Hierarchical Structure Based on Benzimidazole: Synthesis, Characterization, and Application in Ratiometric Electrochemiluminescence Immunoassay.

Efficient and robust electrochemiluminescence (ECL) emitters are crucial for enhancing the ECL immunosensor sensitivity. This study introduces a novel ECL emitter, CoBIM/Cys, featuring a hierarchical core-shell structure. The core of the structure is created through the swift coordination between the sulfhydryl and carboxyl groups of l-cysteine (l-Cys) and cobalt ions (Co2+), while the shell is constructed by sequentially coordinating benzimidazole (BIM) with Co2+. This design yields a greater specific surface area and a more intricate porous structure compared to CoBIM, markedly enhancing mass transfer and luminophore accessibility. Moreover, the l-Cys and Co2+ core introduces Co-S and Co-O catalytic sites, which improve the catalytic decomposition of H2O2, leading to an increased production of hydroperoxyl radicals (OOH•). This mechanism substantially amplifies the ECL performance. Leveraging the competitive interaction between isoluminol and BIM for OOH• during ECL emission, we developed a ratiometric immunosensor for cardiac troponin I (cTnI) detection. This immunosensor demonstrates a remarkably broad detection range (1 pg mL-1 to 10 ng mL-1), a low detection limit (0.4 pg mL-1), and exceptional reproducibility and specificity.

Clinical relevance and advances in detection of translational biomarker cardiac troponin.

Cardiovascular diseases (CVD) are a range of diseases, pointing the functional hindrances in the heart and blood vessels of the human system that contributes to 48.6 % of the world's adult death rate. The diagnosis of CVD relies upon the Electro Cardio Gram (ECG) and detection of muscle markers such as troponins. Among the cardiac trio, Cardiac Troponin I (cTnI) weighing 23 KiloDalton (kDa) is a sorted biomarker for CVD. cTnI remains high in the blood after 1-2 weeks of myocardial damage. Testing of cTnI in CVD patients aids in diagnosis and risk stratification of the disease. Different determination systems including optical, electrochemical, and acoustic have been put forward for monitoring the cTnI which are Point of Care (POC) that promotes simple and sensitive detection of cTnI. The modern era has paved way to high-sensitivity Troponin I (hscTnI) devices that can detect up to 0.01 ng/ml in human blood/plasma/serum. Yet, the practice of hscTnI is impracticable due to cost inefficiency. Development of new hscTnI devices with minimal investment and maximal detection range will meet the global requirement. This review gives an over view on different detection systems of cardiac troponin I which stands as a translational detection molecule for CVDs.

The Value of Combined Detection of Serum BNP, Cardiac Troponin-I and Dynamic Electrocardiogram in Early Clinical Diagnosis and Prognosis of Patients with Acute Myocardial Infarction.

BACKGROUND: Acute myocardial infarction (AMI) is a prevalent cardiovascular disease resulting from myocardial ischemia and necrosis due to coronary artery occlusion. AMI is characterized by a sudden onset and high mortality, underscoring the significance of early diagnosis and treatment for improving patient prognosis. This study endeavors to assess the utility of a combined assessment involving serum brain natriuretic peptide (BNP), cardiac troponin-I (cTnI), and dynamic electrocardiogram (ECG) in the early clinical diagnosis and prognosis prediction of AMI. METHODS: This paper constitutes a retrospective study. All enrolled patients underwent dynamic ECG examination. The study compared the serum levels of BNP and cTnI, along with pertinent dynamic ECG parameters [turbulence slope (TS) and standard deviation (SDNN) of the 24-hour interval between normal atrial depolarization and ventricular depolarization (R-R)], between the observation group (AMI patients) and the control group (patients with unstable angina (UA)). To evaluate the early diagnostic potential of AMI, we utilized receiver operating characteristic (ROC) curves to analyze serum BNP, cTnI, dynamic ECG, and their combined utility. Furthermore, a follow-up period of 6 months was conducted for AMI patients to record major adverse cardiovascular events (MACE). RESULTS: In the observation group, the serum levels of BNP and cTnI were significantly higher than those in the control group (p < 0.001), while dynamic ECG parameters, specifically TS and SDNN, were significantly lower in the observation group compared to the control group (p < 0.001). The results obtained from the ROC curve analysis revealed that the area under the curve (AUC) for BNP, cTnI, dynamic ECG, and their combination in early AMI diagnosis were 0.838, 0.887, 0.874, and 0.974, respectively. The 95% confidence intervals (CI) were 0.781~0.884, 0.836~0.926, 0.822~0.915, and 0.942~0.991, respectively. Sensitivity values were 64.29%, 82.14%, 91.07%, and 88.39%, and specificity values were 91.00%, 88.00%, 70.00%, and 98.00%, respectively. Significantly, the combination of all three markers demonstrated superior efficacy in early AMI diagnosis compared to any single index (p < 0.05). During the 6-month follow-up of 112 AMI patients, 22 experienced MACE. The MACE group exhibited notably higher serum BNP and cTnI levels compared to the non-MACE group. Additionally, dynamic electrocardiogram parameters TS and SDNN demonstrated a significant decrease (p < 0.05) in the MACE group. CONCLUSIONS: The combined assessment of serum BNP, cTnI, and dynamic electrocardiogram enhances the early clinical diagnostic potential for AMI and holds value in assessing the prognosis of AMI patients.

Serum Troponin I Assessments in 5- to 30-Year-Olds After BNT162b2 Vaccination.

INTRODUCTION: Rare myocarditis and pericarditis cases have occurred in coronavirus disease 2019 (COVID-19) messenger RNA (mRNA) vaccine recipients. Troponin levels, a potential marker of myocardial injury, were assessed in healthy participants before and after BNT162b2 vaccination. METHODS: Vaccine-experienced 12- to 30-year-olds in phase 3 crossover C4591031 Substudy B (NCT04955626) who had two or three prior BNT162b2 30-µg doses were randomized to receive BNT162b2 30 µg followed by placebo, or placebo followed by BNT162b2 30 µg, 1 month apart. A participant subset, previously unvaccinated against COVID-19, in the phase 3 C4591007 study (NCT04816643) received up to three vaccinations (BNT162b2 10 µg or placebo [5- to 11-year-olds]) or open-label BNT162b2 30 µg (12- to 15-year-olds). Blood samples collected pre-vaccination, 4 days post-vaccination, and 1-month post-vaccination (C4591031 Substudy B only) were analyzed. Frequencies of elevated troponin I levels (male, > 35 ng/l; female, > 17 ng/l) were assessed. RESULTS: Percentages of 12- to 30-year-olds (n = 1485) in C4591031 Substudy B with elevated troponin levels following BNT162b2 or placebo receipt were 0.5% and 0.8% before vaccination, 0.7% and 1.0% at day 4, and 0.7% and 0.5% at 1 month, respectively. In Study C4591007 (n = 1265), elevated troponin I levels were observed in 0.2, 0.4, and 0.2% of 5- to 11-year-old BNT162b2 recipients at baseline and 4 days post-dose 2 and 3, respectively; corresponding values in 12- to 15-year-olds were 0.4, 0.4, and 0.7%. No 5- to 11-year-old placebo recipients had elevated troponin levels. No myocarditis or pericarditis cases or deaths were reported. CONCLUSIONS: Among 5- to < 30-year-olds in both studies, troponin levels were rarely elevated (≤ 1.0%) and similar before and post-vaccination; troponin levels were also similar between BNT162b2 and placebo in 12- to 30-year-old and 5- to 11-year-old recipients in the respective studies. No myocarditis or pericarditis cases were reported. These findings did not provide evidence that BNT162b2 causes troponin elevations. No utility of routine measurement of troponin levels in asymptomatic BNT162b2 recipients was identified.

CORRELATION OF BLOOD AND SALIVARY TROPONIN IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION: PRELIMINARY STUDY / CORRELAÇÃO DA TROPONINA SANGUÍNEA E SALIVAR EM PACIENTES COM INFARTO AGUDO DO MIOCÁRDIO: ESTUDO PRELIMINAR

Introduction: In the event of myocardial injury, the identification of biomarkers that constitute the cardiac muscle cell, especially troponins, can be observed from blood and saliva samples. The preference for using saliva as a diagnostic fluid is supported by the ease of obtaining it using a non-invasive and potentially pre-hospital method. Objective: To verify the expression of troponin I in salivary fluid in acute myocardial infarction in emergency and pre-hospital screenings and correlate it with plasma troponin I levels. Method: Cross-sectional analytical study of diagnostic testing in 27 patients, 9 women and 18 men, with diagnostic confirmation of acute myocardial infarction. Blood and saliva samples were collected and stored and transported over a period of up to 24 hours for troponina I quantification. Results: The study demonstrated that 44.4% of patients were positive for troponin I in both analyses, with equal dichotomous results in 48.1% of cases. Thus, the salivary troponin test achieved 48% sensitivity and 50% specificity. Conclusion: It was possible to identify troponin in the saliva fluid of patients suffering from acute myocardial infarction, but the probability of a false positive result was 50% and a false negative result was 52%.

Introdução: Na ocorrência da lesão miocárdica, a identificação de biomarcadores constituintes da célula muscular cardíaca, em especial as troponinas, pode ser observada a partir de amostras de sangue e saliva. A preferência pela utilização da saliva como fluído diagnóstico é sustentada pela facilidade de obtenção a partir de método não invasivo e potencialmente pré-hospitalar. Objetivo: Verificar a expressão de troponina I do fluído salivar no infarto agudo do miocárdio em triagens de emergências e pré-hospitalares e correlacioná-la com os níveis plasmáticos da troponina I. Método: Estudo analítico transversal de teste diagnóstico em 27 pacientes, 9 mulheres e 18 homens, com confirmação diagnóstica de infarto agudo do miocárdio. Foram coletadas amostras de sangue e saliva armazenadas e transportadas em período de até 24 h para quantificação da troponina I. Resultados: O estudo demonstrou que 44,4% dos pacientes apresentaram positivação de troponina I em ambas as análises, com igualdade de resultados dicotômicos em 48,1% dos casos. Assim, o teste de troponina salivar obteve 48% de sensibilidade e 50% de especificidade. Conclusão: Foi possível identificar troponina I no fluido da saliva de pacientes em vigência de infarte agudo do miocárdio, mas a probabilidade de ela ter resultado falso positivo foi de 50% e de falso negativo de 52%.

CAN BLOOD AND SALIVARY TROPONIN BE EARLY SIGNALS OF ACUTE MYOCARDIAL INFARCTION? / PODEM A TROPONINA SANGUÍNEA E SALIVAR SER SINALISADORAS PRECOCES DO INFARTO AGUDO DO MIOCÁRDIO?

Introduction: Myocardial injury can be identified by biomarkers extracted from cardiac cells. Troponin is one of them and can be observed in blood and saliva. Saliva is preferred due to its ease of non-invasive and pre-hospital collection. Objective: To review whether the expression of troponin I in salivary fluid in acute myocardial infarction in emergency screening is viable compared to its plasma levels. Method: The literature review was carried out by collecting information published in SciELO, Bibliomed, VHL - Biblioteca Virtual em Saúde, Pubmed and Scopus in Portuguese and English. The search was based on descriptors related to the topic, identified as: "troponin, acute myocardial infarction, cardiac biomarkers, salivary fluid", with AND and OR searches. Results: Were included 109 articles correlated to the theme. Conclusion: Diagnosis based on saliva offers many options and could be a very interesting option for elucidating acute myocardial infarction for general practitioners, nursing homes and transport services quickly, aiding early treatment.

Introdução: A lesão miocárdica pode ser identificada por biomarcadores extraídos das células cardíacas. A troponina é uma delas e pode ser observada no sangue e saliva. A saliva é preferencial pela facilidade de coleta não invasiva e pré-hospitalar. Objetivo: Revisar se a expressão de troponina I do fluído salivar no infarto agudo do miocárdio em triagens de emergências é viável comparado aos seus níveis plasmáticos. Método: A revisão da literatura foi feita colhendo informações publicadas no SciELO, Bibliomed, BVS - Biblioteca Virtual em Saúde, Pubmed e Scopus em português e inglês. A busca foi baseada em descritores relacionados ao tema, identificados como: "troponina, infarto agudo do miocárdio, biomarcadores cardíacos, fluido salivar",  com busca AND e OR. Resultados: Foram incluídos 109 trabalhos. Conclusão: O diagnóstico baseado na saliva oferece muitas opções podendo vir a ser opção muito interessante para elucidação de infarto agudo do miocárdio para o clínico geral, lares de idosos e serviços de transporte com rapidez auxiliando precocidade no tratamento.

Perioperative changes of serum orphanin in diabetic patients and its relationship with sympathetic nervous system.

The occurrence of cardiovascular events in diabetic patients during the perioperative period is related to the activation of sympathetic nerves. Basic research shows that serum nociceptin/orphanin FQ (N/OFQ) levels in diabetic neuropathy rats increased, and N/OFQ reduces the release of norepinephrine (NE). We hypothesize that N/OFQ will affect the sympathetic nervous system during perioperative myocardium of diabetic patients. 66 patients with unilateral knee arthroplasty were divided into diabetes group (D group) and non-diabetes group (N group). Measured blood glucose, serum NE, N/OFQ concentrations at the 30 min before anesthesia (T0), 1 h after surgery (T1), 24 h after surgery (T2) and the cardiac troponinI (cTnI) concentration at T0 and T2. Compared with N group, the concentration of blood glucose, N/OFQ and cTnI in D group was higher and the NE was lower at T0 (P < 0.05). At T1, the blood glucose, N/OFQ, NE concentrations of D group increased, only the blood glucose increased in N group (P < 0.05). Serum N/OFQ of D group from T0 to T1 was correlated with the change trend of blood glucose, NE concentration from T0 to T1 and cTnI from T0 to T2(r = 0.386, P = 0.027; r = 0.350, P = 0.046; r = 0.363, P = 0.038). The outcomes demonstrated that the preoperative serum N/OFQ concentration in diabetic patients was increased, and the increase in N/OFQ concentration during the operation was related to the increase in NE and cTnI concentrations, perioperative N/OFQ may mediate myocardial injury through sympathetic nervous system.

Cardiac troponins and coronary artery calcium score: a systematic review.

An early diagnosis of atherosclerosis, particularly in subclinical status, can play a remarkable role in reducing mortality and morbidity. Because of coronary artery calcification (CAC) nature in radiation exposure, finding biomarkers associated with CAC could be useful in identifying individuals at high risk of CAC score. In this review, we focused on the association of cardiac troponins (hs-cTns) and CAC to achieve insight into the pathophysiology of CAC. In October 2022, we systematically searched Web of Science, Scopus, PubMed, and Embase databases to find human observational studies which have investigated the association of CAC with cardiac troponins. To appraise the included articles, we used the Newcastle Ottawa scale (NOS). Out of 520 records, 10 eligible studies were included. Based on findings from longitudinal studies and cross-sectional analyses, troponin T and I were correlated with occurrence of CAC and its severity. Two of the most important risk factors that affect the correlation between hs-cTns serum levels and CAC were age and gender. The elevation of cardiac troponins may affect the progression of CAC and future cardiovascular diseases. Verifying the association between cardiac troponins and CAC may lead to identify individuals exposed to enhanced risk of cardiovascular disease (CVD) complications and could establish innovative targets for pharmacological therapy.

Exercise training and high-sensitivity cardiac troponin-I in patients with heart failure with reduced ejection fraction.

AIMS: The aims of this sub-study of the SMARTEX trial were (1) to evaluate the effects of a 12-week exercise training programme on serum levels of high sensitivity cardiac troponin I (hs-cTnI) in patients with moderate chronic heart failure (CHF), in New York Heart Association class II-III with reduced ejection fraction (HFrEF) and (2) to explore the associations with left ventricular remodelling, functional capacity and filling pressures measured with N-terminal pro brain natriuretic peptide (NT-proBNP). METHODS AND RESULTS: In this sub-study, 196 patients were randomly assigned to high intensity interval training (HIIT, n = 70), moderate continuous training (MCT, n = 59) or recommendation of regular exercise (RRE), (n = 67) for 12 weeks. To reveal potential difference between structured intervention and control, HIIT and MCT groups were merged and named supervised exercise training (SET) group. The RRE group constituted the control group (CG). To avoid contributing factors to myocardial injury, we also evaluated changes in patients without additional co-morbidities (atrial fibrillation, hypertension, diabetes mellitus, and chronic obstructive pulmonary disease). The relationship between hs-cTnI and left ventricular end-diastolic diameter (LVEDD), VO2peak, and NT-proBNP was analysed by linear mixed models. At 12 weeks, Hs-cTnI levels were modestly but significantly reduced in the SET group from median 11.9 ng/L (interquartile ratio, IQR 7.1-21.8) to 11.5 ng/L (IQR 7.0-20.7), P = 0.030. There was no between-group difference (SET vs. CG, P = 0.116). There was a numerical but not significant reduction in hs-cTnI for the whole population (P = 0.067) after 12 weeks. For the sub-group of patients without additional co-morbidities, there was a significant between-group difference: SET group (delta -1.2 ng/L, IQR -2.7 to 0.1) versus CG (delta -0.1 ng/L, IQR -0.4 to 0.7), P = 0.007. In the SET group, hs-cTnI changed from 10.9 ng/L (IQR 6.0-22.7) to 9.2 ng/L (IQR 5.2-20.5) (P = 0.002), whereas there was no change in the CG (6.4 to 5.8 ng/L, P = 0.64). Changes in hs-cTnI (all patients) were significantly associated with changes in; LVEDD, VO2peak, and NT-proBNP, respectively. CONCLUSIONS: In patients with stable HFrEF, 12 weeks of structured exercise intervention was associated with a modest, but significant reduction of hs-cTnI. There was no significant difference between intervention group and control group. In the sub-group of patients without additional co-morbidities, this difference was highly significant. The alterations in hs-cTnI were associated with reduction of LVEDD and natriuretic peptide concentrations as well as improved functional capacity.

Dendritic quinary PtRhMoCoFe high-entropy alloy as a robust immunosensing nanoplatform for ultrasensitive detection of biomarker.

Recently, high-entropy alloys have superior physicochemical properties as compared to conventional alloys for their glamorous "cocktail effect". Nevertheless, they are scarcely applied to electrochemical immunoassays until now. Herein, uniform PtRhMoCoFe high-entropy alloyed nanodendrites (HEANDs) were synthesized by a wet-chemical co-reduction method, where glucose and oleylamine behaved as the co-reducing agents. Then, a series of characterizations were conducted to illustrate the synergistic effect among multiple metals and fascinating structural characteristics of PtRhMoCoFe HEANDs. The obtained high-entropy alloy was adopted to build a electrochemical label-free biosensor for ultrasensitive bioassay of biomarker cTnI. In the optimized analytical system, the resultant sensor exhibited a dynamic linear range of 0.0001-200 ng mL-1 and a low detection limit of 0.0095 pg mL-1 (S/N = 3). Eventually, this sensing platform was further explored in serum samples with satisfied recovery (102.0 %). This research renders some constructive insights for synthesis of high-entropy alloys and their expanded applications in bioassays and bio-devices.

Differences in Troponin I and Troponin T Release in High-Performance Athletes Outside of Competition.

Troponin I and troponin T are critical biomarkers for myocardial infarction and damage and are pivotal in cardiological and laboratory diagnostics, including emergency settings. Rapid testing protocols have been developed for urgent care, particularly in emergency outpatient clinics. Studies indicate that strenuous physical activity can cause transient increases in these troponin levels, which are typically considered benign. This research focused on 219 elite athletes from national teams, evaluating their troponin I and T levels as part of routine sports medical exams, independent of competition-related physical stress. The results showed that 9.2% (18 athletes) had elevated troponin I levels above the reporting threshold, while their troponin T levels remained within the normal range. Conversely, only 0.9% (two athletes) had normal troponin I but raised troponin T levels, and 2.3% (five athletes) exhibited increases in both markers. No significant cardiovascular differences were noted between those with elevated troponin levels and those without. This study concludes that elevated troponin I is a common response to the intense physical training endured by high-performance endurance athletes, whereas troponin T elevation does not seem to be directly linked to physical exertion in this group. For cardiac assessments, particularly when ruling out cardiac damage in these athletes, troponin T might be a more reliable indicator than troponin I.