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Replenishing insulin-producing pancreatic ß cell mass will benefit both type I and type II diabetics. In adults, pancreatic ß cells are generated primarily by self-duplication. We report on a mouse model of insulin resistance that induces dramatic pancreatic ß cell proliferation and ß cell mass expansion. Using this model, we identify a hormone, betatrophin, that is primarily expressed in liver and fat. Expression of betatrophin correlates with ß cell proliferation in other mouse models of insulin resistance and during gestation. Transient expression of betatrophin in mouse liver significantly and specifically promotes pancreatic ß cell proliferation, expands ß cell mass, and improves glucose tolerance. Thus, betatrophin treatment could augment or replace insulin injections by increasing the number of endogenous insulin-producing cells in diabetics.
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Proliferação de Células , Células Secretoras de Insulina/metabolismo , Pâncreas/citologia , Hormônios Peptídicos/metabolismo , Tecido Adiposo Branco/metabolismo , Sequência de Aminoácidos , Proteína 8 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Animais , Feminino , Glucose/metabolismo , Humanos , Resistência à Insulina , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Pâncreas/metabolismo , Hormônios Peptídicos/química , Hormônios Peptídicos/genética , Peptídeos/administração & dosagem , Receptor de Insulina/antagonistas & inibidores , Alinhamento de SequênciaRESUMO
Plant inflorescence architecture is determined by inflorescence meristem (IM) activity and controlled by genetic mechanisms associated with environmental factors. In Arabidopsis (Arabidopsis thaliana), TERMINAL FLOWER1 (TFL1) is expressed in the IM and is required to maintain indeterminate growth, whereas LEAFY (LFY) is expressed in the floral meristems (FMs) formed at the periphery of the IM and is required to activate determinate floral development. Here, we address how Arabidopsis indeterminate inflorescence growth is determined. We show that the 26S proteasome subunit REGULATORY PARTICLE AAA-ATPASE 2a (RPT2a) is required to maintain the indeterminate inflorescence architecture in Arabidopsis. rpt2a mutants display reduced TFL1 expression levels and ectopic LFY expression in the IM and develop a determinate zigzag-shaped inflorescence. We further found that RPT2a promotes DNA METHYLTRANSFERASE1 degradation, leading to DNA hypomethylation upstream of TFL1 and high TFL1 expression levels in the wild-type IM. Overall, our work reveals that proteolytic input into the epigenetic regulation of TFL1 expression directs inflorescence architecture in Arabidopsis, adding an additional layer to stem cell regulation.
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Aging is characterized as the process of functional decline in an organism from adulthood, often marked by a progressive loss of cellular function and systemic deterioration of multiple tissues. Among the numerous molecular, cellular, and systemic hallmarks associated with aging, mitochondrial dysfunction is considered one of the pivotal factors that initiates the aging process. During aging, mitochondria undergo varying degrees of damage, resulting in impaired energy production and disruption of the homeostatic regulation of mitochondrial quality control systems, which in turn affects cellular energy metabolism and results in cellular dysfunction, accelerating the aging process. AMP-activated protein kinase (AMPK) and the mechanistic target of rapamycin complex 1 (mTORC1) are two central kinase complexes responsible for sensing intracellular nutrient levels, regulating metabolic homeostasis, modulating aging and play a crucial role in maintaining the homeostatic balance of mitochondria. Our previous studies found that the novel compound tetramethylpyrazine nitrone (TBN) can protect mitochondria via the AMPK/mTOR pathway in many animal models, extending healthy lifespan through the Nrf2 signaling pathway in nematodes. Building upon this foundation, we have posited a reasonable hypothesis, TBN can improve mitochondrial function to delay aging by regulating the AMPK/mTORC1 signaling pathway. This study focuses on the C. elegans, exploring the impact and underlying mechanisms of TBN on aging and mitochondrial function (especially the mitochondrial quality control system) during the aging process. The present studies demonstrated that TBN extends lifespan of wild-type nematodes and is associated with the AMPK/mTORC1 signaling pathway. TBN elevated ATP and NAD+ levels in aging nematodes while orchestrating mitochondrial biogenesis and mitophagy. Moreover, TBN was observed to significantly enhance normal activities during aging in C. elegans, such as mobility and pharyngeal pumping, concurrently impeding lipofuscin accumulation that were closely associated with AMPK and mTORC1. This study not only highlights the delayed effects of TBN on aging but also underscores its potential application in strategies aimed at improving mitochondrial function via the AMPK/mTOR pathway in C. elegans.
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Proteínas Quinases Ativadas por AMP , Envelhecimento , Caenorhabditis elegans , Alvo Mecanístico do Complexo 1 de Rapamicina , Mitocôndrias , Pirazinas , Transdução de Sinais , Animais , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efeitos dos fármacos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Pirazinas/farmacologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Envelhecimento/metabolismo , Envelhecimento/efeitos dos fármacos , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Óxidos de Nitrogênio/metabolismoRESUMO
Solar thermal utilization has broad applications in a variety of fields. Currently, maximizing the photo-thermal conversion efficiency remains a research hotspot in this field. The exquisite plant structures in nature have greatly inspired human structural design across many domains. In this work, inspired by the photosynthesis of helical grass, a HM type solar absorber made in graphene-based composite sheets is used for solar thermal conversion. The unique design promoted more effective solar energy into thermal energy through multiple reflections and scattering of solar photons. Notably, the Helical Micropillar (HM) is fabricated using a one-step projection 3D printing process based on a special 3D helical beam. As a result, the solar absorber's absorbance value can reach 0.83 in the 400-2500 nm range, and the surface temperature increased by ≈128.3% relative to the original temperature. The temperature rise rate of the solar absorber reached 22.4 °C min-1, demonstrating the significant potential of the HM in practical applications of solar thermal energy collection and utilization.
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Ulcerative colitis (UC) is an idiopathic, chronic inflammatory condition of the colon, characterized by repeated attacks, a lack of effective treatment options, and significant physical and mental health complications for patients. The endoplasmic reticulum (ER) is a vital intracellular organelle in maintaining cellular homeostasis. Endoplasmic reticulum stress (ERS) is induced when the body is exposed to adverse external stimuli. Numerous studies have shown that ERS-induced apoptosis plays a vital role in the pathogenesis of UC. Mogroside V (MV), an active ingredient of Monk fruit, has demonstrated excellent anti-inflammatory and antioxidant effects. In this study, we investigated the therapeutic effects of MV on dextran sulfate sodium (DSS)-induced UC and its potential mechanisms based on ERS. The results showed that MV exerted a protective effect against DSS-induced UC in mice as reflected by reduced DAI scores, increased colon length, reduced histological scores of the colon, and levels of pro-inflammatory cytokines, as well as decreased intestinal permeability. In addition, the expression of ERS pathway including BIP, PERK, eIF2α, ATF4, CHOP, as well as the apoptosis-related protein including Caspase-12, Bcl-2 and Bax, was found to be elevated in UC. However, MV treatment significantly inhibited the UC and reversed the expression of inflammation signaling pathway including ERS and ERS-induced apoptosis. Additionally, the addition of tunicamycin (Tm), an ERS activator, significantly weakened the therapeutic effect of MV on UC in mice. These findings suggest that MV may be a therapeutic agent for the treatment of DSS-induced UC by inhibiting the activation of the ERS-apoptosis pathway, and may provide a novel avenue for the treatment of UC.
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Apoptose , Colite Ulcerativa , Sulfato de Dextrana , Estresse do Retículo Endoplasmático , Animais , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/metabolismo , Apoptose/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Colo/patologia , Colo/efeitos dos fármacos , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Camundongos , Citocinas/metabolismo , Permeabilidade/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
Modern human society is burdened with the pandemic of cardiovascular and metabolic diseases. Metrnl is a widely distributed secreted protein in the body, involved in regulating glucose and lipid metabolism and maintaining cardiovascular system homeostasis. In this review, we present the predictive and therapeutic roles of Metrnl in various cardiovascular and metabolic diseases, including atherosclerosis, ischemic heart disease, cardiac remodeling, heart failure, hypertension, chemotherapy-induced myocardial injury, diabetes mellitus, and obesity.
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Biomarcadores , Doenças Cardiovasculares , Doenças Metabólicas , Humanos , Doenças Metabólicas/metabolismo , Doenças Metabólicas/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Biomarcadores/metabolismo , AnimaisRESUMO
A novel actinobacterium strain, designated HUAS 2-6 T, was isolated from the rhizosphere soil of Camellia oleifera Abel collected from Taoyuan County, Northwestern Hunan Province, South China. This strain was subjected to a polyphasic taxonomic study. Strain HUAS 2-6 T is characterized by morphology typical of members of the genus Streptomyces, with deep purplish vinaceous aerial mycelia and deep dull lavender substrate mycelia. Strain HUAS 2-6 T, based on the full-length 16S rRNA gene sequence analysis, exhibited the highest similarities to S. puniciscabiei S77T (99.31%), S. filipinensis NBRC 12860 T (99.10%), S. yaanensis CGMCC 4.7035 T (99.09%), S. fodineus TW1S1T (99.08%), S. broussonetiae CICC 24819 T (98.76%), S. achromogenes JCM 4121 T (98.69%), S. barringtoniae JA03T (98.69%), and less than 98.70% with other validly species. In phylogenomic tree, strain HUAS 2-6 T was clustered together with S. broussonetiae CICC 24819 T, suggesting that they were closely related to each other. However, average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) between them were much less than the species cutoff values (ANI 96.7% and dDDH 70%). Moreover, in phenotypic and chemotaxonomic characteristics, strain HUAS 2-6 T is distinct from S. broussonetiae CICC 24819 T. On the basis of the polyphasic data, strain HUAS 2-6 T is proposed to represent a novel species, Streptomyces camelliae sp. nov. (= MCCC 1K04729T = JCM 35918 T).
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Camellia , DNA Bacteriano , Filogenia , RNA Ribossômico 16S , Rizosfera , Microbiologia do Solo , Streptomyces , Streptomyces/isolamento & purificação , Streptomyces/genética , Streptomyces/classificação , Camellia/microbiologia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , China , Ácidos Graxos/análise , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Composição de BasesRESUMO
Adhesion is the key functionality to pick-and-place objects in wet environments. Recently, various micropillars and external stimuli have been proposed to achieve reversible wet adhesion. However, their underlying mechanisms of liquid/solid regulations have not been sufficiently revealed. Herein, two kinds of magnetically responsive micropillar arrays with different terminals (pointed and flat) are developed using a spray self-assembly method. The coupling effect of geometric structures and external stimuli on the wet adhesion performance between a solid substrate and the developed surface is discussed. In situ observation and analysis of theoretical models demonstrate that changes in adhesive forces are mainly caused by the length of the liquid bridge and the apparent contact angle of the developed surface. The adhesion conversion efficiency in the presence of an on/off magnetic field can achieve a highest value of 72% for the micropillar arrays with flat terminals, which exceeds 3 times that of the micropillar arrays with pointed terminals. In addition, wet adhesion measurements during the process of repeatedly switching the magnetic field demonstrate the durability and cyclic reversibility of the magnetically responsive surface. Furthermore, the transportation of microcomponents verifies the application potential of the magnetically responsive surface, which may provide inspiration for transfer printing systems and wet climbing robots.
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Inflammatory bowel disease (IBD) is a chronic inflammatory disease involving the digestive tract, characterized by abdominal pain, diarrhea, rectal bleeding, and so on, which can make patients physically weakened and live difficultly. Although IBD has been recognized for many years, the pathogenesis of IBD has not yet been established and damage to intestinal barrier is thought to be closely associated with IBD. Intestinal barrier is an innate barrier that maintains the homeostasis of the intestinal environment and impedes pathogenic bacteria and toxins, and the endoplasmic reticulum (ER) has recently been found to be involved in maintaining the integrity of intestinal barrier. Endoplasmic reticulum stress (ERS) is a status of endoplasmic reticulum damaged when unfolded or misfolded proteins accumulate in excess of the degradation systematic clearance limit of the misfolded proteins. The regulation of ERS on protein folding synthesis and maintenance of cellular homeostasis is an important factor in influencing the integrity of the intestinal barrier. This paper mainly discusses the relationship between ERS and the intestinal barrier, aiming to understand the regulatory role of ERS on the intestinal barrier and the mechanism and to improve new solutions and notions for the treatment or prevention of IBD.
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Estresse do Retículo Endoplasmático , Doenças Inflamatórias Intestinais , Humanos , Estresse do Retículo Endoplasmático/fisiologia , Intestinos , Doenças Inflamatórias Intestinais/metabolismo , Dobramento de Proteína , Retículo Endoplasmático/metabolismo , Mucosa Intestinal/metabolismo , Resposta a Proteínas não DobradasRESUMO
With the widespread application of assisted reproductive technology, the health issues of offspring conceived through assisted reproductive technology have also received increasing attention. Animal experiments and clinical studies have found subclinical adverse changes in the cardiovascular system of assisted reproductive offspring. Assisted reproductive technology itself may be just one of the many factors contributing to this phenomenon, with epigenetics playing an important role. Ultrasound technology can be used to assess the morphological structure and function of the cardiovascular system in assisted reproductive offspring from the fetal stage, providing the possibility to study the potential cardiovascular damage in this large population. This review aims to explore the effects and mechanisms of assisted reproductive technology on the cardiovascular system of offspring and provide a review of the research progress in ultrasound technology in this area.
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Sistema Cardiovascular , Técnicas de Reprodução Assistida , Ultrassonografia , Técnicas de Reprodução Assistida/efeitos adversos , Sistema Cardiovascular/diagnóstico por imagemRESUMO
In this paper, we propose a novel distributed algorithm based on model predictive control and alternating direction multiplier method (DMPC-ADMM) for cooperative trajectory planning of quadrotor swarms. First, a receding horizon trajectory planning optimization problem is constructed, in which the differential flatness property is used to deal with the nonlinear dynamics of quadrotors while we design a relaxed form of the discrete-time control barrier function (DCBF) constraint to balance feasibility and safety. Then, we decompose the original trajectory planning problem by ADMM and solve it in a fully distributed manner with peer-to-peer communication, which induces the quadrotors within the communication range to reach a consensus on their future trajectories to enhance safety. In addition, an event-triggered mechanism is designed to reduce the communication overhead. The simulation results verify that the trajectories generated by our method are real-time, safe, and smooth. A comprehensive comparison with the centralized strategy and several other distributed strategies in terms of real-time, safety, and feasibility verifies that our method is more suitable for the trajectory planning of large-scale quadrotor swarms.
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Seven new pentasaccharides (1-7), rehmaglupentasaccharides A-G, were isolated from the air-dried roots of Rehmannia glutinosa. Their structures were established from the spectroscopic data obtained and by chemical evidence. The known verbascose (8) and stachyose (9) were also obtained in the current investigation, and the structure of stachyose was unequivocally defined using X-ray diffraction data. Compounds 1-9 were tested for their cytotoxicity against five human tumor cell lines, influence on dopamine receptor activation, and proliferation effects against Lactobacillus reuteri.
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Rehmannia , Humanos , Rehmannia/química , Linhagem Celular , Raízes de Plantas/químicaRESUMO
Herein we report a structure-unit-based asymmetric total synthesis of sinulochmodin C, a norcembranoid diterpenoid bearing a transannular strained ether bridge ß-keto tetrahydrofuran moiety. Our synthetic route features an intramolecular double Michael addition to construct stereospecifically the [7,6,5,5] tetracyclic skeleton, a vinylogous hydroxylation/oxidation procedure or a stereospecific epoxide opening/oxidation sequence to establish the γ-keto enone intermediate, a Lewis acid/Brønsted acid mediated transannular oxa-Michael addition to fuse the ß-keto tetrahydrofuran moiety, a Mukaiyama hydration/Pd-C hydrogenation to reverse the C1-configuration of the isopropenyl unit, and a bioinspired transformation of sinulochmodin C into scabrolide A.
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Although highly appealing for rapid access of molecular complexity, multi-functionalization of alkenes that allows incorporation of more than two functional groups remains a prominent challenge. Herein, we report a novel strategy that merges dipolar cycloaddition with photoredox promoted radical ring-opening remote C(sp3)-H functionalization, thus enabling a smooth 1,2,5-trifunctionalization of unactivated alkenes. A highly regioselective [3+2] cycloaddition anchors a reaction trigger onto alkene substrates. The subsequent halogen atom transfer (XAT) selectively initiates ring-opening process, which is followed by a series of 1,5-hydrogen atom transfer (1,5-HAT) and intermolecular fluorine atom transfer (FAT) events. With this method, site-selective introduction of three different functional groups is accomplished and a broad spectrum of valuable ß-hydroxyl-ε-fluoro-nitrile products are synthesized from readily available terminal alkenes.
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Antireflective microstructures fabricated using femtosecond laser possess wide-ranging applicability and high stability across different spectral bands. However, due to the limited aspect ratio of the focused light field, traditional femtosecond laser manufacturing faces challenges in efficiently fabricating antireflective microstructures with high aspect ratio and small period, which are essential for antireflection, on curved surfaces. In this study, we present a robust and efficient method for fabricating high-aspect-ratio and basal surface insensitive antireflective microstructures using a spatially shaped Bessel-like beam. Based on theoretical simulation, a redesigned telescopic system is proposed to flexibly equalize the intensity of the Bessel beam along its propagation direction, facilitating the fabrication of antireflective subwavelength structures on the entire convex lens. The fabricated microstructures, featuring a width of less than 2â µm and a depth of 1â µm, enhance transmittance from 75% to 85% on Diamond-ZnS composite material (D-ZnS) surfaces. Our approach enables the creation of high aspect ratio subwavelength structures with a z-position difference exceeding 600â µm. This practical, efficient, and cost-effective method is facilitated for producing antireflective surfaces on aero-optical components utilized in aviation.
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Applications of nanoparticles (NPs) in nanodrugs, food additives, and cosmetics can result in the presence of nanomaterials in the human circulatory system and their attachment to red blood cells (RBCs), which may lead to cytotoxic effects. To investigate the interactions of NPs with RBC membranes (RBCm), supported erythrocyte membranes (SRBCm) were developed on piezoelectric sensors in a quartz crystal microbalance with dissipation (QCM-D) at 25 °C. A well-dispersed RBCm suspension at 1 mM NaCl and 0.2 mM NaHCO3 was obtained from whole blood and comprised colloidal membrane fragments with the average hydrodynamic diameter and zeta potential of 390 nm and -0.53 mV, respectively, at pH 7.0. The thin and rigid SRBCm was formed mainly through the deposition of RBCm fragments on the poly-l-lysine-modified crystal sensor, leading to the average frequency shift of -26.2 Hz and the low ratio of the dissipation to frequency shift (7.2 × 10-8 Hz-1). The complete coverage of SRBCm was indicated by the plateau of the frequency shift in the stage of SRBCm formation and no deposition of negatively charged 106 nm polystyrene nanoparticles (PSNPs) on the SRBCm. Atomic force microscopy and immunofluorescence microscopy images showed that RBCm aggregates with the average size of 420 nm and erythrocyte membrane proteins existed on SRBCm, respectively. The methods of determining attachment efficiencies of model positively charged NPs (i.e., hematite NPs or HemNPs) and model negatively charged NPs (i.e., PSNPs) on SRBCm were demonstrated in 1 mM NaCl solution at pH 5.1 and pH 7.0, respectively. HemNPs exhibited a favorable deposition with an attachment efficiency of 0.99 while PSNPs did not show any attachment propensity toward SRBCm.
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Nanopartículas , Nanoestruturas , Humanos , Cloreto de Sódio , Nanopartículas/química , Membrana Eritrocítica , Técnicas de Microbalança de Cristal de QuartzoRESUMO
BACKGROUND: People with dementia often do not receive optimal person-centred care (PCC) in care settings. Family members can play a vital role as care partners to support the person with dementia with their psychosocial needs. Participatory research that includes the perspectives of those with lived experience is essential for developing high-quality dementia care and practices. OBJECTIVE: Throughout 2021-2022, a mobile app, called WhatMatters, was co-developed to provide easy-to-access and personalised support for people with dementia in hospitals and long-term care homes, with input from patients/residents, family partners and healthcare staff. This article discusses and critically reflects on the experiences of patients/residents, family partners, and healthcare staff involved in the co-design process. METHODS: For the app development, we applied a participatory co-design approach, guided by a User Experience (UX) model. The process involved co-design workshops and user testing sessions with users (patients/residents, family partners, healthcare staff) to co-develop the WhatMatters prototype. We also conducted focus groups and one on one interviews with staff and caregiver participants to explore their experiences. Our research team, which also included patient partners, took part in regular team meetings during the app's development, where we discussed and reflected on the co-design process. Reflexive thematic analysis was performed to identify themes that represent the challenges and rewarding experiences of the users involved in the co-design process, which guided our overall reflective process. FINDINGS: Our reflective analysis identified five themes (1) clarifying the co-design process, (2) ensuring inclusive collaborations of various users, and (3) supporting expression of emotion in a virtual environment, (4) feeling a sense of achievement and (5) feeling valued. IMPLICATIONS: WhatMatters offers potential for providing personally relevant and engaging resources in dementia care. Including the voices of relevant users is crucial to ensure meaningful benefits for patients/residents. We offer insights and lessons learned about the co-design process, and explore the challenges of involving people with lived experiences of dementia in co-design work, particularly during the pandemic.
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Demência , Aplicativos Móveis , Humanos , Hospitais , Assistência de Longa Duração , Assistência Centrada no Paciente , Demência/terapia , Demência/psicologiaRESUMO
INTRODUCTION: Immune checkpoint inhibitors can cause immune-related toxicity in various systems, with myocarditis being the most severe and life-threatening manifestation. This report presents a case in which myocarditis developed following administration of programmed cell death protein-1 (PD-1) inhibitors therapy. We describe the diagnosis and treatment of this patient in detail. CASE REPORT: We present the case of a 59-year-old female diagnosed with post-operative esophageal cancer and hepatic metastases. The patient underwent second-line treatment with domestically-made PD-1 inhibitor, camrelizumab, in combination with paclitaxel (albumin-bound) and carboplatin for two cycles. During the course of treatment, an electrocardiogram (ECG) revealed ST segment elevation in leads II, III, aVF, V2, V3, and V4, along with T wave changes in leads I and aVL. Laboratory examinations showed abnormal levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin T (cTnT). Despite the absence of clinical symptoms, the patient was routinely hospitalized three weeks later. Based on the findings from the ECG, cardiac biomarkers, echocardiography, echocardiogram, cardiac magnetic resonance, and angiography, she was diagnosed with immune-checkpoint-inhibitors-related myocarditis. MANAGEMENT AND OUTCOME: The patient received immunoglobulin (0.5â g/kg/day) and was initially given methylprednisolone (1000â mg/day). Methylprednisolone was gradually reduced to 40â mg/day in 2 weeks. During this time, the levels of biomarkers indicative of myocardial injury also exhibited a simultaneous decline. DISCUSSION: This case highlights the importance of early detection and prompt intervention, including initiating appropriate steroid therapy and discontinuing of immune checkpoint inhibitors. Such measures can effectively prevent morbidity and mortality, ultimately leading to an improved prognosis.