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3.
Anal Chem ; 96(37): 15042-15049, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39219053

RESUMEN

Despite many luminescent advantages including outstanding absorption coefficient and high quantum yield, pyrene and its derivatives have been suffering from a dramatic aggregation-caused quenching (ACQ) effect. Although the dramatic ACQ effect of pyrene-based fluorophores has been restrained in pyrene-doped metal-organic frameworks (MOFs), the low loading of fluorescent (FL) units substantially impedes the improved luminescent behaviors. Herein, pyrene-based MOFs hydrogel was synthesized with a high loading of pyrene as the unique organic linker blocks instead of a dopant in MOFs. The gel matrix contributed to rigidifying the location of the FL emitters and achieving intensive FL emission and high luminescent stability and therefore efficiently overcoming the ACQ effect. Furthermore, the protonation of pyrene in the MOFs hydrogel remarkably decreased the luminescent intensity, which endowed the FL hydrogel with highly pH-responsive activity in the broad range (pH 4-10). Interestingly, glucose oxidase was immobilized into ZIF-8 as a highly efficient luminescent quencher, which contributed to catalyzing the form of gluconic acid and thus drastically quenching the FL signal of the MOFs hydrogel. Furthermore, the emitter-quencher pair of pyrene-based MOFs hydrogel and glucose oxidase was successfully employed to develop an ultrasensitive FL immunoassay platform for cardiac troponin I (as a model analyte). The limit of detection for cardiac troponin I was 5.2 pg/mL (3σ). The proof-of-principle study demonstrated the thrilling auxiliary effect of tailorable MOFs hydrogel on boosting the feasibility of aqueous insoluble FL chromophores for trace analysis.


Asunto(s)
Hidrogeles , Estructuras Metalorgánicas , Pirenos , Troponina I , Pirenos/química , Estructuras Metalorgánicas/química , Troponina I/análisis , Troponina I/sangre , Concentración de Iones de Hidrógeno , Humanos , Hidrogeles/química , Inmunoensayo/métodos , Colorantes Fluorescentes/química , Fluorescencia
4.
J Am Heart Assoc ; 13(18): e034850, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39248254

RESUMEN

BACKGROUND: Higher cardiac troponin is associated with worse outcomes in patients with acute heart failure. The significance of repeat measurements over hours remains unclear. We assessed whether a repeat measurement and the Δ between measurements of high-sensitivity cardiac troponin I (hs-cTnI) were associated with outcomes in hypervolemic patients with acute heart failure without acute coronary syndrome. METHODS AND RESULTS: We analyzed 582 individuals from AKINESIS (Acute Kidney Injury Neutrophil Gelatinase-Associated Lipocalin Evaluation of Symptomatic Heart Failure Study) with hs-cTnI measured ≤12 hours from admission and repeated ≤6 hours thereafter. Associations between hs-cTnI levels and their Δ with short-term (death, intensive care unit admission, receipt of inotropes, or positive pressure ventilation during hospitalization) and long-term (death or heart failure readmission within 1 year) outcomes were assessed. The average age was 69±13 years, 62% were men, 65% were White, 46% had coronary artery disease, and 22% had chest pain. Median hs-cTnI levels were 27 (interquartile range [IQR], 13-62) ng/L initially and 28 (IQR, 14-68) ng/L subsequently, with a Δ of 0 [IQR, -2 to 4] ng/L over 3.4±1 hours. Only the second measurement was associated with short-term outcomes (odds ratio, 1.14 per 2-fold higher [95% CI, 1.02-1.28]). Both individual measurements and the Δ were associated with long-term outcomes (hazard ratios, 1.09, 1.12, and 1.16 for first, second, and Δ, respectively). Associated risk for the first and second measurements were not constant over the year but highest early after being measured and decreased over 1 year. CONCLUSIONS: Repeat measurements of hs-cTnI over hours can identify individuals with acute heart failure without acute coronary syndrome at risk for short- and long-term outcomes.


Asunto(s)
Biomarcadores , Insuficiencia Cardíaca , Troponina I , Humanos , Masculino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , Insuficiencia Cardíaca/mortalidad , Anciano , Femenino , Enfermedad Aguda , Persona de Mediana Edad , Biomarcadores/sangre , Troponina I/sangre , Factores de Tiempo , Anciano de 80 o más Años , Pronóstico , Valor Predictivo de las Pruebas , Factores de Riesgo , Estudios Prospectivos , Readmisión del Paciente/estadística & datos numéricos
5.
Physiol Res ; 73(4): 543-552, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39264077

RESUMEN

In this study, we investigated the mechanism underlying electrocardiogram (ECG) alterations in a rabbit model of acute pulmonary thromboembolism (PTE). Twelve healthy adult New Zealand white rabbits were used, with eight in the experimental group (PTE group) and four in the control group. After developing the rabbit model of acute PTE, ECG and coronary angiography were performed. HE staining was conducted on the right and left ventricular tissues, and polymerase chain reaction (PCR) was used to determine brain natriuretic peptide (BNP), tumor necrosis factor-alpha (TNF-?), and Troponin I (TNI) mRNA expression in the myocardium. There were considerable changes in the ST segment of the ECG in the PTE group. Coronary angiography revealed the absence of spasm, stenosis, and occlusion. In the plasma of the PTE group, the levels of D-dimer, BNP, TNF-?, and TNI were significantly elevated, and these changes were statistically significant (P<0.05). PCR analysis of ventricular myocardial tissue indicated significantly higher levels of BNP, TNF-?, and TNI mRNA in the PTE group than in the control group. These differences were statistically significant (P<0.05). The ST-T variations on the ECG of rabbits with acute PTE correlate strongly with the temporary changes in right heart volume caused by acute PTE. Keywords: Animal model of pulmonary embolism, B-type natriuretic peptide, Electrocardiogram, Pulmonary thromboembolism, Troponin I, Tumor necrosis factor-alpha.


Asunto(s)
Modelos Animales de Enfermedad , Electrocardiografía , Embolia Pulmonar , Animales , Conejos , Embolia Pulmonar/fisiopatología , Embolia Pulmonar/sangre , Masculino , Troponina I/sangre , Troponina I/metabolismo , Enfermedad Aguda , Péptido Natriurético Encefálico/sangre , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/genética
6.
J Am Heart Assoc ; 13(17): e035053, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39190583

RESUMEN

BACKGROUND: Acute myocardial injury is associated with poor outcomes in patients with acute ischemic stroke, but its prognostic significance in patients with spontaneous intracerebral hemorrhage remains unclear. We investigated whether acute myocardial injury and the direction of the cardiac troponin I (cTnI) change (rising versus falling) affect post-intracerebral hemorrhage outcomes. METHODS AND RESULTS: We re-analyzed the FAST (Factor-Seven-for-Acute-Hemorrhagic-Stroke) trial. Acute myocardial injury was defined as at least 1 cTnI value above the upper reference limit with a rise/fall of >20%. Logistic regression tested for associations (1) between acute myocardial injury (presence versus absence) and poor outcome (modified Rankin Scale 4-6) and mortality at 15 and 90 days; (2) among 3 groups (rising versus falling versus no acute myocardial injury) and outcomes. Among the 841 FAST participants, 785 patients were included. Acute myocardial injury was detected in 29% (n=227); 170 had rising cTnI. At 15 and 90 days, respectively, those with acute myocardial injury had higher odds of poor outcome (adjusted odds ratio) ([aOR] 2.3 [95% CI, 1.3-3.9]); and adjusted odds ratio 2.5 [95% CI, 1.6-3.9];, and higher odds of mortality (adjusted odds ratio 2.4 [95% CI, 1.4-4.3]; and adjusted odds ratio 2.2 [CI, 1.3-3.6]) than patients without. There was no interaction between FAST group assignment and myocardial injury, and associations between myocardial injury and outcomes were consistent across group assignments. Rising cTnI was associated with the highest risk of poor outcomes and mortality. CONCLUSIONS: In this secondary analysis of the FAST trial, acute myocardial injury was common and associated with poor outcomes. The direction of the cTnI change might provide additional risk stratification after intracerebral hemorrhage.


Asunto(s)
Biomarcadores , Troponina I , Humanos , Masculino , Femenino , Troponina I/sangre , Anciano , Persona de Mediana Edad , Biomarcadores/sangre , Pronóstico , Hemorragia Cerebral/mortalidad , Hemorragia Cerebral/sangre , Hemorragia Cerebral/diagnóstico , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo
7.
Zhonghua Er Ke Za Zhi ; 62(9): 872-876, 2024 Sep 02.
Artículo en Chino | MEDLINE | ID: mdl-39192446

RESUMEN

Objective: To analyze the clinical characteristics, treatment, and outcomes of children with complete left bundle branch block (CLBBB) mediated by maternal autoantibodies. Methods: A retrospective analysis was conducted on nine children diagnosed with maternal autoantibody-mediated CLBBB, treated at Beijing Anzhen Hospital and Fujian Provincial Hospital from March 2015 to August 2023. Their clinical characteristics, electrocardiographic and echocardiographic findings before and after treatment were reviewed. Paired sample t-test was used for inter-group comparison. Results: Among the mothers, 6 had positive antinuclear antibodies (ANA), 5 had anti-Sjogren syndrome antigen A antibodies, and 3 had anti-Ro-52 antibodies. The cohort included one female and eight male children, diagnosed with CLBBB at the age of 1 (2, 13) months. The positive autoantibodies in the infants, consisted with maternal antibodies, were detected within the first 3 months of life among 3 cases. Treatments included anti-heart failure therapy, myocardial nutritional support, intravenous immunoglobulin (IVIG) and glucocorticoids. Before treatment, the levels of troponin I (0.175 (0.060, 10.270) µg/L) and N-terminal pro-B-type natriuretic peptide (420 (327, 12 865) ng/L) were elevated, which normalized in most cases after treatment. Post-treatment, the QRS duration significantly shortened compared to pre-treatment ((137±15) vs.(169±25) ms, t=3.76, P<0.001), and the QTc interval significantly decreased ((433±41) vs. (514±27) ms, t=4.95, P=0.001). Before treatment, varying degrees of mitral and tricuspid regurgitation and marked interventricular septal dyskinesia were observed in echocardiography. After treatment, valve regurgitation and ventricular septum motion significantly improved, with a marked increase in left ventricular ejection fraction ((51±13)% vs. (27±6)%, t=-6.66, P<0.001). Conclusions: Maternal autoantibody-mediated CLBBB in children presents with chronic heart failure in infancy. Early treatment with anti-heart failure medications, IVIG and glucocorticoids can improve clinical symptoms.


Asunto(s)
Anticuerpos Antinucleares , Autoanticuerpos , Bloqueo de Rama , Electrocardiografía , Humanos , Femenino , Estudios Retrospectivos , Masculino , Autoanticuerpos/sangre , Anticuerpos Antinucleares/sangre , Lactante , Ecocardiografía , Inmunoglobulinas Intravenosas/uso terapéutico , Péptido Natriurético Encefálico/sangre , Troponina I/sangre , Glucocorticoides/uso terapéutico , Fragmentos de Péptidos/inmunología , Madres
8.
Int J Mol Sci ; 25(16)2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39201603

RESUMEN

Immunodetection of cardiac isoforms of troponin I (cTnI) and troponin T (cTnT) in blood samples is widely used for the diagnosis of acute myocardial infarction. The cardiac troponin complex (ITC-complex), comprising cTnI, cTnT, and troponin C (TnC), makes up a large portion of troponins released into the bloodstream after the necrosis of cardiomyocytes. However, the stability of the ITC-complex has not been fully investigated. This study aimed to investigate the stability of the ITC-complex in blood samples. A native ITC-complex was incubated in buffer solutions, serum, and citrate, heparin, or EDTA plasma at various temperatures. Western blotting and gel filtration were performed, and troponins were detected using specific monoclonal antibodies. The ITC-complex dissociated at 37 °C in buffers with or without anticoagulants, in citrate, heparin, and EDTA plasmas, and in serum, into a binary cTnI-TnC complex (IC-complex) and free cTnT. In plasma containing heparin and EDTA, the IC-complex further dissociated into free TnC and cTnI. No dissociation was found at 4 °C or at room temperature (RT) in all matrices within 24 h except for EDTA plasma. After incubation at 37 °C in EDTA plasma and serum, dissociation was accompanied by proteolytic degradation of both cTnI and cTnT. The presence of anti-troponin autoantibodies in the sample impeded dissociation of the ITC-complex. The ITC-complex dissociates in vitro to form the IC-complex and free cTnT at 37 °C but is mostly stable at 4 °C or RT. Further dissociation of the IC-complex occurs at 37 °C in plasmas containing heparin and EDTA.


Asunto(s)
Anticoagulantes , Troponina I , Troponina T , Anticoagulantes/farmacología , Humanos , Troponina I/sangre , Troponina T/sangre , Troponina C/sangre , Ácido Edético/química , Ácido Edético/farmacología , Heparina , Ácido Cítrico
9.
Biosensors (Basel) ; 14(8)2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39194610

RESUMEN

Exercise-induced muscle injury is one of the most common types of sports injuries. Skeletal muscle troponin I (skTnI) serves as an ideal biomarker in assessing such injuries, facilitating timely detection and evaluation. In this study, we develop a fluorescent sandwich lateral flow immunoassay (LFIA) combined with a desktop analyzer for rapid detection of skTnI. Through optimizing the reaction system, the assay achieves a satisfying detection performance, reaching a limit of detection (LOD) of 0.5 ng/mL with a turnaround time of 15 min. The proposed detection platform offers portability, ease of use, and high sensitivity, which facilitates the monitoring of exercise-induced muscle injuries at the point of care. This feature is particularly advantageous for end users, enabling timely detection of sports-related injuries and ultimately enhancing prognosis and sports life.


Asunto(s)
Músculo Esquelético , Sistemas de Atención de Punto , Troponina I , Troponina I/sangre , Humanos , Inmunoensayo , Músculo Esquelético/lesiones , Biomarcadores/sangre , Técnicas Biosensibles , Límite de Detección
10.
Biosensors (Basel) ; 14(8)2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39194616

RESUMEN

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.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Infarto del Miocardio , Embolia Pulmonar , Embolia Pulmonar/diagnóstico , Infarto del Miocardio/diagnóstico , Humanos , Grafito/química , Electrodos , Troponina I/análisis
11.
Nat Cardiovasc Res ; 3(8): 987-1002, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39196031

RESUMEN

Cardiac troponin I (cTnI) is a key regulator of cardiomyocyte contraction. However, its role in mitochondria is unknown. Here we show that cTnI localized to mitochondria in the heart, inhibited mitochondrial functions when stably expressed in noncardiac cells and increased the opening of the mitochondrial permeability transition pore under oxidative stress. Direct, specific and saturable binding of cTnI to F1FO-ATP synthase was demonstrated in vitro using immune-captured ATP synthase and in cells using proximity ligation assay. cTnI binding doubled ATPase activity, whereas skeletal troponin I and several human pathogenic cTnI variants associated with familial hypertrophic cardiomyopathy did not. A rationally designed peptide, P888, inhibited cTnI binding to ATP synthase, inhibited cTnI-induced increase in ATPase activity in vitro and reduced cardiac injury following transient ischemia in vivo. We suggest that cTnI-bound ATP synthase results in lower ATP levels, and releasing this interaction during cardiac ischemia-reperfusion may increase the reservoir of functional mitochondria to reduce cardiac injury.


Asunto(s)
Mitocondrias Cardíacas , ATPasas de Translocación de Protón Mitocondriales , Troponina I , Animales , Humanos , Masculino , Ratones , Ratas , Adenosina Trifosfato/metabolismo , Modelos Animales de Enfermedad , Células HEK293 , Ratones Endogámicos C57BL , Mitocondrias Cardíacas/metabolismo , Poro de Transición de la Permeabilidad Mitocondrial/metabolismo , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Isquemia Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Estrés Oxidativo/efectos de los fármacos , Unión Proteica , Troponina I/metabolismo
12.
Open Heart ; 11(2)2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39097328

RESUMEN

BACKGROUND: Guidelines recommend the use of risk scores to select patients for further investigation after myocardial infarction has been ruled out but their utility to identify those with coronary artery disease is uncertain. METHODS: In a prospective cohort study, patients with intermediate high-sensitivity cardiac troponin I concentrations (5 ng/L to sex-specific 99th percentile) in whom myocardial infarction was ruled out were enrolled and underwent coronary CT angiography (CCTA) after hospital discharge. History, ECG, Age, Risk factors, Troponin (HEART), Emergency Department Assessment of Chest Pain Score (EDACS), Global Registry of Acute Coronary Event (GRACE), Thrombolysis In Myocardial Infarction (TIMI), Systematic COronary Risk Evaluation 2 and Pooled Cohort Equation risk scores were calculated and the odds ratio (OR) and diagnostic performance for obstructive coronary artery disease were determined using established thresholds. RESULTS: Of 167 patients enrolled (64±12 years, 28% female), 29.9% (50/167) had obstructive coronary artery disease. The odds of having obstructive disease were increased for all scores with the lowest and highest increase observed for an EDACS score ≥16 (OR 2.2 (1.1-4.6)) and a TIMI risk score ≥1 (OR 12.9 (3.0-56.0)), respectively. The positive predictive value (PPV) was low for all scores but was highest for a GRACE score >88 identifying 39% as high risk with a PPV of 41.9% (30.4-54.2%). The negative predictive value (NPV) varied from 77.3% to 95.2% but was highest for a TIMI score of 0 identifying 26% as low risk with an NPV of 95.2% (87.2-100%). CONCLUSIONS: In patients with intermediate cardiac troponin concentrations in whom myocardial infarction has been excluded, clinical risk scores can help identify patients with and without coronary artery disease, although the performance of established risk thresholds is suboptimal for utilisation in clinical practice. TRIAL REGISTRATION NUMBER: NCT04549805.


Asunto(s)
Síndrome Coronario Agudo , Biomarcadores , Angiografía Coronaria , Enfermedad de la Arteria Coronaria , Troponina I , Humanos , Femenino , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo/métodos , Biomarcadores/sangre , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/epidemiología , Síndrome Coronario Agudo/sangre , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/epidemiología , Anciano , Troponina I/sangre , Factores de Riesgo , Angiografía por Tomografía Computarizada , Valor Predictivo de las Pruebas , Pronóstico
13.
ACS Appl Bio Mater ; 7(8): 5258-5267, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39103296

RESUMEN

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.


Asunto(s)
Cobre , Técnicas Electroquímicas , Oro , Ensayo de Materiales , Nanopartículas del Metal , Troponina I , Oro/química , Cobre/química , Troponina I/sangre , Troponina I/análisis , Troponina I/inmunología , Nanopartículas del Metal/química , Humanos , Inmunoensayo/métodos , Técnicas Biosensibles , Materiales Biocompatibles/química , Tamaño de la Partícula , Polifenoles
14.
J Am Heart Assoc ; 13(16): e034382, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39158569

RESUMEN

BACKGROUND: The implications of exercise-induced cardiac troponin elevation in healthy individuals are unclear. This study aimed to determine if individuals with a high exercise-induced cardiac troponin I (cTnI) response have alterations in myocardial function following high-intensity endurance exercise compared with normal-cTnI responders. METHODS AND RESULTS: Study individuals were recruited from previous participants in a 91-km mountain bike cycling race (the North Sea Race) and were classified as high- (n=34) or normal-cTnI responders (n=25) based on maximal cTnI values after the recruitment race. The present study exposed all participants to 2 prolonged high-intensity exercises: a combined lactate threshold and cardiopulmonary exercise test and repeated participation in the North Sea Race. Echocardiography was performed before, immediately after, and 24 hours following exercise. All study individuals (n=59) had normal coronary arteries, and were aged 51±10 years; 46 (74%) were men. There were no differences in baseline characteristics between the high- and normal-cTnI responders. Maximal cTnI levels 3 hours after exercise were significantly higher in the high- compared with normal-cTnI group (P<0.001-0.027). Following exercise, there were no differences in global ventricular function between the 2 groups. In contrast, high-cTnI responders had significantly lower regional strain in the anteroseptal segments following exercise, with more profound changes after the race. CONCLUSIONS: High-cTnI responders had lower anteroseptal segmental strain shortly after exercise than normal-cTnI responders. However, there were no permanent alterations in myocardial strain, indicating no short- or long-term adverse consequences of these exercise-induced alterations in myocardial function. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02166216.


Asunto(s)
Biomarcadores , Troponina I , Función Ventricular Izquierda , Humanos , Masculino , Troponina I/sangre , Femenino , Persona de Mediana Edad , Función Ventricular Izquierda/fisiología , Adulto , Biomarcadores/sangre , Ejercicio Físico/fisiología , Prueba de Esfuerzo , Ciclismo/fisiología , Regulación hacia Arriba , Ecocardiografía
15.
Open Vet J ; 14(7): 1625-1633, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39175974

RESUMEN

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.


Asunto(s)
Enfermedades de los Perros , Insuficiencia de la Válvula Mitral , Troponina I , Perros , Animales , Troponina I/sangre , Insuficiencia de la Válvula Mitral/veterinaria , Insuficiencia de la Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/sangre , Enfermedades de los Perros/cirugía , Enfermedades de los Perros/sangre , Masculino , Femenino , Periodo Perioperatorio/veterinaria
16.
Physiol Rep ; 12(16): e70012, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39169429

RESUMEN

Aging is associated with cardiac contractile abnormalities, but the etiology of these contractile deficits is unclear. We hypothesized that cardiac contractile and regulatory protein expression is altered during aging. To investigate this possibility, left ventricular (LV) lysates were prepared from young (6 months) and old (24 months) Fischer344 rats. There are no age-related changes in SERCA2 expression or phospholamban phosphorylation. Additionally, neither titin isoform expression nor phosphorylation differed. However, there is a significant increase in ß-isoform of the myosin heavy chain (MyHC) expression and phosphorylation of TnI and MyBP-C during aging. In permeabilized strips of papillary muscle, force and Ca2+ sensitivity are reduced during aging, consistent with the increase in ß-MyHC expression and TnI phosphorylation. However, the increase in MyBP-C phosphorylation during aging may represent a mechanism to compensate for age-related contractile deficits. In isolated cardiomyocytes loaded with Fura-2, the peak of the Ca2+ transient is reduced, but the kinetics of the Ca2+ transient are not altered. Furthermore, the extent of shortening and the rates of both sarcomere shortening and re-lengthening are reduced. These results demonstrate that aging is associated with changes in contractile and regulatory protein expression and phosphorylation, which affect the mechanical properties of cardiac muscle.


Asunto(s)
Envejecimiento , Contracción Miocárdica , Miocitos Cardíacos , Ratas Endogámicas F344 , Animales , Masculino , Contracción Miocárdica/fisiología , Envejecimiento/metabolismo , Envejecimiento/fisiología , Ratas , Fosforilación , Miocitos Cardíacos/metabolismo , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Cadenas Pesadas de Miosina/metabolismo , Proteínas de Unión al Calcio/metabolismo , Conectina/metabolismo , Troponina I/metabolismo , Calcio/metabolismo , Proteínas de Unión a Calmodulina/metabolismo , Proteínas Portadoras
17.
J Am Coll Cardiol ; 84(8): 726-740, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39142727

RESUMEN

BACKGROUND: Point-of-care (POC) high-sensitivity cardiac troponin assays may further accelerate the diagnosis of myocardial infarction (MI). OBJECTIVES: This study sought to assess the clinical and analytical performance of the novel high-sensitivity cardiac troponin I (hs-cTnI)-SPINCHIP POC test. METHODS: Adult patients presenting with acute chest discomfort to the emergency department were enrolled in an international, diagnostic, multicenter study. The final diagnosis was centrally adjudicated by 2 independent cardiologists using all clinical information. We compared the discriminatory performance of hs-cTnI-SPINCHIP with current established central laboratory assays and derived an assay-specific hs-cTnI-SPINCHIP 0/1-hour algorithm. Secondary analyses included sample type comparisons (whole blood, fresh/frozen plasma, and capillary finger prick) and precision analysis. RESULTS: MI was the adjudicated final diagnosis in 214 (19%) of 1,102 patients. Area under the receiver-operating characteristic curve was 0.94 (95% CI: 0.92-0.95) for hs-cTnI-SPINCHIP vs 0.94 (95% CI: 0.92-0.95) for hs-cTnI-Architect (P = 0.907) and 0.93 (95% CI: 0.91-0.95) for high-sensitivity cardiac troponin T Elecsys (P = 0.305). A cutoff <7 ng/L at presentation (if chest pain onset was >3 hours) or <7 ng/L together with a 0/1-hour delta of <4 ng/L ruled out 51% with a sensitivity and negative predictive value of 100% (95% CI: 97.7%-100%) and 100% (95% CI: 99.0%-100%), respectively. A hs-cTnI-SPINCHIP concentration ≥36 ng/L or a 0/1-hour delta ≥11 ng/L ruled in 27% with a specificity and positive predictive value of 90.9% (95% CI: 88.3%-92.9%) and 72.9% (95% CI: 66.4%-78.6%), respectively. Bootstrap internal validation confirmed excellent diagnostic performance. High agreement was observed between different sample types. CONCLUSIONS: The SPINCHIP hs-cTnI POC test has very high diagnostic accuracy. Its assay-specific 0/1-hour algorithm achieved very high sensitivity/negative predictive value and specificity/positive predictive value for rule-out/in MI. (Advantageous Predictors of Acute Coronary Syndromes Evaluation [APACE] Study [APACE]; NCT00470587).


Asunto(s)
Infarto del Miocardio , Troponina I , Humanos , Troponina I/sangre , Masculino , Femenino , Persona de Mediana Edad , Anciano , Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Sistemas de Atención de Punto , Biomarcadores/sangre , Estudios Prospectivos , Sensibilidad y Especificidad
18.
Sci Rep ; 14(1): 18113, 2024 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103434

RESUMEN

Tracer antibodies, which are labelled with fluorescent or other type of reporter molecules, are widely employed in diagnostic immunoassays. Time-resolved fluorescence immunoassay (TRFIA), recognized as one of the most sensitive immunoassay techniques, utilizes tracers labelled with lanthanide ion (Ln) chelates. The conventional approach for conjugating isothiocyanate (ITC) Ln-chelates to antibodies involves random chemical targeting of the primary amino group of Lys residues, requiring typically overnight exposure to an elevated pH of 9-9.3 and leading to heterogeneity. Moreover, efforts to enhance the sensitivity of the assays by introducing a higher number of Ln-chelates per tracer antibody are associated with an elevated risk of targeting critical amino acid residues in the binding site, compromising the binding properties of the antibody. Herein, we report a method to precisely label recombinant antibodies with a defined number of Ln-chelates in a well-controlled manner by employing the SpyTag/SpyCatcher protein ligation technology. We demonstrate the functionality of the method with a full-length recombinant antibody (IgG) as well as an antibody fragment by producing site-specifically labelled antibodies for TRFIA for cardiac troponin I (cTnI) detection with a significant improvement in assay sensitivity compared to that with conventionally labelled tracer antibodies. Overall, our data clearly illustrates the benefits of the site-specific labelling strategy for generating high-performing tracer antibodies for TRF immunoassays.


Asunto(s)
Elementos de la Serie de los Lantanoides , Humanos , Elementos de la Serie de los Lantanoides/química , Anticuerpos/inmunología , Anticuerpos/química , Inmunoensayo/métodos , Troponina I/inmunología , Troponina I/análisis , Inmunoglobulina G , Quelantes/química , Coloración y Etiquetado/métodos
19.
BMJ Case Rep ; 17(8)2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39117364

RESUMEN

A 22-kg female in early childhood with a history of reactive airway disease presented to a paediatric emergency department with acute shortness of breath, tachypnoea and wheezing. Despite treatment with albuterol and corticosteroids, her bronchospasm persisted, prompting the administration of terbutaline. The patient received 220 mcg (10 mcg/kg) terbutaline intravenously, followed immediately by an inadvertent supratherapeutic intravenous dose of 10 000 mcg (454.5 mcg/kg). The patient's laboratory results obtained minutes after the medication error were notable for: potassium, 3.1 mmol/L, lactate, 2.6 mmol/L and troponin I, 0.30 ng/mL (normal <0.03 ng/mL). Over the next 48 hours, serial serum troponin values decreased. The patient was discharged home approximately 72 hours after the initial presentation and she remained well based on follow-up calls over the next several months. Given the timing and trend of troponin concentrations, we do not believe the terbutaline overdose to be responsible for the myocardial injury.


Asunto(s)
Sobredosis de Droga , Terbutalina , Humanos , Terbutalina/administración & dosificación , Femenino , Broncodilatadores/administración & dosificación , Administración Intravenosa , Troponina I/sangre , Preescolar
20.
Arch Dermatol Res ; 316(7): 466, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990351

RESUMEN

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.


Asunto(s)
Pénfigo , Troponina I , Humanos , Troponina I/sangre , Masculino , Femenino , Pénfigo/sangre , Pénfigo/diagnóstico , Estudios Transversales , Persona de Mediana Edad , Adulto , Estudios de Casos y Controles , Biomarcadores/sangre , Índice de Severidad de la Enfermedad , Anciano
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