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1.
Clin Transl Immunology ; 13(7): e1519, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38975278

RESUMO

Objectives: CAR-T cells are being investigated as a novel immunotherapy for glioblastoma, but clinical success has been limited. We recently described fibroblast activation protein (FAP) as an ideal target antigen for glioblastoma immunotherapy, with expression on both tumor cells and tumor blood vessels. However, CAR-T cells targeting FAP have never been investigated as a therapy for glioblastoma. Methods: We generated a novel FAP targeting CAR with CD3ζ and CD28 signalling domains and tested the resulting CAR-T cells for their lytic activity and cytokine secretion function in vitro (using real-time impedance, flow cytometry, imaging and bead-based cytokine assays), and in vivo (using a xenograft mimicking the natural heterogeneity of human glioblastoma). Results: FAP-CAR-T cells exhibited target specificity against model cell lines and potent cytotoxicity against patient-derived glioma neural stem cells, even when only a subpopulation expressed FAP, indicating a bystander killing mechanism. Using co-culture assays, we confirmed FAP-CAR-T cells mediate bystander killing of antigen-negative tumor cells, but only after activation by FAP-positive target cells. This bystander killing was at least partially mediated by soluble factors and amplified by IL-2 which activated the non-transduced fraction of the CAR-T product. Finally, a low dose of intravenously administered FAP-CAR-T cells controlled, without overt toxicity, the growth of subcutaneous tumors created using a mixture of antigen-negative and antigen-positive glioblastoma cells. Conclusions: Our findings advance FAP as a leading candidate for clinical CAR-T therapy of glioblastoma and highlight under-recognised antigen nonspecific mechanisms that may contribute meaningfully to the antitumor activity of CAR-T cells.

2.
J Cardiothorac Surg ; 19(1): 286, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734628

RESUMO

Acute type A aortic dissection is a severe cardiovascular disease characterized by rapid onset and high mortality. Traditionally, urgent open aortic repair is performed after admission to prevent aortic rupture and death. However, when combined with malperfusion syndrome, the low perfusion of the superior mesenteric artery can further lead to intestinal necrosis, significantly impacting the surgery's prognosis and potentially resulting in adverse consequences, bringing. This presents great significant challenges in treatment. Based on recent domestic and international research literature, this paper reviews the mechanism, current treatment approaches, and selection of surgical methods for poor organ perfusion caused by acute type A aortic dissection. The literature review findings suggest that central aortic repair can be employed for the treatment of acute type A aortic dissection with inadequate perfusion of the superior mesenteric artery. The superior mesenteric artery can be windowed and (/or) stented, followed by delayed aortic repair. Priority should be given to revascularization of the superior mesenteric artery, followed by central aortic repair. During central aortic repair, direct blood perfusion should be performed on the distal true lumen of the superior mesenteric artery, leading to resulting in favorable therapeutic outcomes. The research results indicate that even after surgical aortic repair, intestinal ischemic necrosis may still occur. In such cases, prompt laparotomy and necessary necrotic bowel resection are crucial for saving the patient's life.


Assuntos
Dissecção Aórtica , Artéria Mesentérica Superior , Necrose , Humanos , Dissecção Aórtica/cirurgia , Dissecção Aórtica/complicações , Artéria Mesentérica Superior/cirurgia , Intestinos/irrigação sanguínea , Intestinos/cirurgia , Isquemia Mesentérica/cirurgia , Isquemia/cirurgia , Aneurisma Aórtico/cirurgia , Aneurisma Aórtico/complicações , Doença Aguda
3.
J Cardiothorac Surg ; 19(1): 273, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702812

RESUMO

Acute type A aortic dissection is a life-threatening cardiovascular disease characterized by rapid onset and high mortality. Emergency surgery is the preferred and reliable treatment option. However, postoperative complications significantly impact patient prognosis. Hypoxemia, a common complication, poses challenges in clinical treatment, negatively affecting patient outcomes and increasing the risk of mortality. Therefore, it is crucial to study and comprehend the risk factors and treatment strategies for hypoxemia following acute type A aortic dissection to facilitate early intervention.


Assuntos
Dissecção Aórtica , Hipóxia , Complicações Pós-Operatórias , Humanos , Dissecção Aórtica/cirurgia , Dissecção Aórtica/complicações , Fatores de Risco , Hipóxia/etiologia , Doença Aguda , Aneurisma da Aorta Torácica/cirurgia
4.
J Immunother Cancer ; 12(5)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38754916

RESUMO

BACKGROUND: Chimeric antigen receptor (CAR) T cell therapies specific for the CD19 and B-cell maturation antigen have become an approved standard of care worldwide for relapsed and refractory B-cell malignancies. If CAR-T cell therapy for non-hematological malignancies is to achieve the same stage of clinical development, then iterative early-phase clinical testing can add value to the clinical development process for evaluating CAR-T cell products containing different CAR designs and manufactured under differing conditions. METHODS: We conducted a phase 1 trial of third-generation GD2-specific CAR-T cell therapy, which has previously been tested in neuroblastoma patients. In this study, the GD2-CAR-T therapy was evaluated for the first time in metastatic melanoma patients in combination with BRAF/MEK inhibitor therapy, and as a monotherapy in patients with colorectal cancer and a patient with fibromyxoid sarcoma. Feasibility and safety were determined and persistence studies, multiplex cytokine arrays on sera and detailed immune phenotyping of the original CAR-T products, the circulating CAR-T cells, and, in select patients, the tumor-infiltrating CAR-T cells were performed. RESULTS: We demonstrate the feasibility of manufacturing CAR-T products at point of care for patients with solid cancer and show that a single intravenous infusion was well tolerated with no dose-limiting toxicities or severe adverse events. In addition, we note significant improvements in CAR-T cell immune phenotype, and expansion when a modified manufacturing procedure was adopted for the latter 6 patients recruited to this 12-patient trial. We also show evidence of CAR-T cell-mediated immune activity and in some patients expanded subsets of circulating myeloid cells after CAR-T cell therapy. CONCLUSIONS: This is the first report of third-generation GD2-targeting CAR-T cells in patients with metastatic melanoma and other solid cancers such as colorectal cancer, showing feasibility, safety and immune activity, but limited clinical effect. TRIAL REGISTRATION NUMBER: ACTRN12613000198729.


Assuntos
Imunoterapia Adotiva , Melanoma , Receptores de Antígenos Quiméricos , Humanos , Melanoma/imunologia , Melanoma/terapia , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/efeitos adversos , Receptores de Antígenos Quiméricos/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Gangliosídeos/imunologia , Adulto , Idoso , Linfócitos T/imunologia , Resultado do Tratamento
6.
Asian J Surg ; 47(2): 982-989, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38030495

RESUMO

BACKGROUND: Surgery is the preferred treatment for acute Stanford type A aortic dissection (STAAD); however, due to the complexity of the procedure, cardiac ischaemia and cardiopulmonary bypass (CPB) time are longer than general heart surgery, leading to complications. In this present study, we used an integrated tetra-furcate graft for both modified aortic root and distal arch anastomoses (frozen elephant trunk technique, [FET]), and investigated postoperative outcomes associated with this technique in patients with STAAD. METHODS: We included a total of 140 patients who underwent total arch replacement and FET between January 2019 and June 2022 in the present study, 41 patients who underwent the modified technique, and 99 who underwent the graft eversion technique. We subsequently analyzed the perioperative outcomes to compare the differences between the two techniques. RESULTS: There were no statistically significant differences between the two groups in regards to the preoperative characteristics; however, the intraoperative CPB, cardiac ischaemia, and operation times of the modified technique group were significantly shorter than those of the eversion technique group (P = 0.02, P = 0.01, and P = 0.04, respectively), as were postoperative hypoxaemia, intensive care unit (ICU) stay, and ventilation times (P = 0.04, P = 0.03, and P = 0.04, respectively). Additionally, the degree of postoperative bilirubin elevation was milder in the modified technique group (P = 0.002 for direct bilirubin and P = 0.01 for indirect bilirubin). CONCLUSIONS: The modified anastomosis technique can significantly shorten CPB, cardiac ischemia, and operation times, and reduce the intraoperative FFP transfusion and postoperative hypoxemia times. This modified technique, therefore, is worth utilizing for patients with STAAD.


Assuntos
Dissecção Aórtica , Implante de Prótese Vascular , Humanos , Aorta Torácica/cirurgia , Implante de Prótese Vascular/métodos , Anastomose Cirúrgica , Bilirrubina , Isquemia/cirurgia , Estudos Retrospectivos , Stents , Resultado do Tratamento
7.
Biol Trace Elem Res ; 202(5): 1901-1909, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37578601

RESUMO

Female subfertility has been a growing concern for reproductive health. Assisted reproductive technologies make pregnancy possible, but the outcome rate is still suboptimal. Zinc is an essential factor for fertility and development. Zinc levels in follicular fluids were measured by electrochemical method, and we found that zinc in the follicular fluids was related to high-quality embryo rate (R = 0.39, p = 0.01). Basal estradiol levels and estradiol levels on the day of HCG injection were negatively correlated with zinc concentrations in the follicular fluid (R = - 0.53, p < 0.001; R = - 0.32, p < 0.05), and estradiol promoted ZnT 9 protein expression in cumulus granulosa cells in vitro and in vivo. When the zinc level was at 3.63-3.85 µg/mL, follicular fluid samples had the highest SOD activity. Therefore, zinc played an important role in improving oocyte development by increasing antioxidant capacity. Our results suggested that estradiol affected zinc homeostasis in follicles by controlling the expression of ZnT 9, which in turn influenced the potential of oocytes to develop into good-quality embryos. This study to provide tangible improvements to patient outcomes will make it a focus of both scientific and translational efforts in the future.


Assuntos
Estradiol , Folículo Ovariano , Gravidez , Humanos , Feminino , Estradiol/metabolismo , Progesterona/metabolismo , Fertilização in vitro , Zinco/metabolismo
8.
Mol Med Rep ; 29(2)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38131196

RESUMO

The quality of oocytes in patients with polycystic ovary syndrome (PCOS) decreases, which is closely related to the function of oocytes' mitochondria. If mitochondrial dysfunction is involved in PCOS, it is likely to affect the function of cumulus cells. However, the mechanism of mitochondrial dysfunction remains unclear. In the present study, granulosa cells were collected from women attending the Hebei Reproductive Health Hospital and were divided into the normal ovarian reserve group (CON group) and the PCOS group. The mitochondrial ultrastructure was observed by transmission electron microscope, and the mitochondrial function was determined by detecting the ATP content, reactive oxygen species levels, the number of mitochondria and the mitochondrial membrane potential. Additionally, western blotting was used to compare the expression levels of mitochondrial kinetic protein, the related channel protein, between the two groups. In the present study, it was found that patients with PCOS had abnormal granulosa cell morphology, increased mitochondrial abnormalities, decreased mitochondrial function and disturbed mitochondrial dynamics. In addition, the silent information regulator 1/phosphorylated­AMP­activated protein kinase/peroxisome proliferator­activated receptor­Î³ coactivator 1α pathway expression was decreased, and it was hypothesized that the decreased mitochondrial mass in the PCOS group was associated with it.


Assuntos
Doenças Mitocondriais , Síndrome do Ovário Policístico , Humanos , Feminino , Síndrome do Ovário Policístico/metabolismo , Células da Granulosa/metabolismo , Oócitos/metabolismo , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo
9.
Molecules ; 28(18)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37764423

RESUMO

(1) Background: Solanum nigrum L. is a plant of the genus Solanum in the family Solanaceae and is commonly used to treat tumors. Solasonin (SS) is a steroidal alkaloid extracted from Solanum nigrum L. that has anti-colorectal cancer (CRC) activity. (2) Methods: Column chromatography, semi-preparative HPLC and cellular activity screening were used to isolate potential anti-CRC active compounds in Solanum nigrum L., and structure identification using 1H-NMR and 13C-NMR techniques. Expression levels of HDAC in CRC were mined in the UALCAN database. The in vitro effects of SS on SW620 cell line and its mechanism were examined via Western blot, EdU staining, flow cytometry and immunofluorescence. CRC xenograft model and IHC staining were mainly used to evaluate the role of SS in vivo. (3) Results: The results showed that SS was the most potent anti-CRC component in Solanum nigrum L., which induced apoptosis and cell cycle arrest in the SW620 cell line. HDAC was highly expressed in CRC. The treatment of SW620 cell line with SS resulted in a significant downregulation of HDAC, an increase in the level of P53 acetylation and a subsequent increase in the level of P21. The in vivo validation results showed that SS could effectively inhibit CRC growth, which was associated with the downregulation of HDAC. (4) Conclusions: SS treatment for CRC mainly works through the induction of apoptosis and cycle arrest, and its mechanism of action is mainly related to HDAC-induced P53 acetylation, and the HDAC/P53 signaling pathway may be a potential pathway for the treatment of CRC.


Assuntos
Neoplasias , Solanum nigrum , Solanum , Humanos , Acetilação , Proteína Supressora de Tumor p53/genética , Regulação para Baixo
11.
Sci Total Environ ; 904: 166883, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37690764

RESUMO

Mature landfill leachate is a refractory organic wastewater, and needs physical and chemical pretreatments contemporaneously, e.g. iron-carbon micro-electrolysis (IC-ME). In this study, a novel iron-carbon (Fe-C) material was synthesized from waste activated sludge to be utilized in IC-ME for landfill leachate treatment. The pyrolysis temperature, mass ratio of iron to carbon, and solid-liquid ratio in leachate treatment were optimized as 900 °C with 1.59 and 34.7 g/L. Under these optimal conditions, the chemical oxygen demand (COD) removal efficiency reached 79.44 %, which was 2.6 times higher than that of commercial Fe-C material (30.1%). This excellent COD removal performance was indicated to a better mesoporous structure, and uniform distribution of zero-valent iron in novel Fe-C material derived from sludge. The contribution order of COD removal in IC-ME treatment for landfill leachate was proven as coagulation, adsorption, and redox effects by a contrast experiment. The removal of COD includes synthetic organic compounds, e.g. carcinogens, pharmaceuticals and personal care products. The contents of CHO, CHON, and CHOS compounds of dissolved organic matter (DOM) in the leachate were decreased, and both the molecular weight and unsaturation of lipids, lignin, and tannic acids concentration were also reduced. Some newly generated small molecular DOM in the treated leachate further confirmed the existence of the redox effect to degrade DOM in leachate. The total cost of sludge-derived Fe-C material was only USD$ 152.8/t, which could save 76% of total compared with that of commercial Fe-C materials. This study expands the prominent source of Fe-C materials with excellent performance, and deepens the understanding of its application for leachate treatment.

12.
J Agric Food Chem ; 71(37): 13889-13898, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37695809

RESUMO

Amatoxins are polypeptides that cause 90% of fatalities from accidental ingestion of poisonous mushrooms. Unfortunately, there are no specific antidotes against amatoxins poisoning, hence preparation of high-affinity antibodies, understanding the receptor (amatoxins) and ligand (antibody) mechanism, and establishing a straightforward screening approach are of great significance for confirming poison agents and clinical diagnosis. Here, anti-amatoxins monoclonal antibody (mAb) 9B2 was prepared and the recognition mechanism was investigated. The approach is useful for designing desirable immunogens, developing new antibodies with improved performance, and constructing effective immunoassays. Based on the mAb, we designed a centrifugal disk-like microfluidics chip and developed a fully automated immunoassay capable of detecting amatoxins poisoning in various samples including serum, urine, and mushrooms. The whole detection process could be automatically accomplished within 30 min, with a limit of detection of 0.08 to 0.12 µg/L for real samples, ∼30-fold more sensitive than conventional enzyme-linked immunosorbent assay (ELISA). Our platform not only provided a practical approach for performing poison agent confirmation and clinical diagnosis but also had important implications for improving the survival of patients with mushroom poisoning.


Assuntos
Agaricales , Venenos , Humanos , Imunoensaio , Ensaio de Imunoadsorção Enzimática , Anticorpos
13.
Aging (Albany NY) ; 15(17): 8537-8551, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37659107

RESUMO

This article presents a formula for modeling the lifetime incidence of cancer in humans. The formula utilizes a Poisson distribution-based "np" model to predict cancer incidence, with "n" representing the effective number of cell turnover and "p" representing the probability of single-cell transformation. The model accurately predicts the observed incidence of cancer in humans when a reduction in cell turnover due to aging is taken into account. The model also suggests that cancer development is ultimately inevitable. The article proposes a theory of aging based on this concept, called the "np" theory. According to this theory, an organism maintains its order by balancing cellular entropy through continuous proliferation. However, cellular "information entropy" in the form of accumulated DNA mutations increases irreversibly over time, restricting the total number of cells an organism can generate throughout its lifetime. When cell division slows down and fails to compensate for the increased entropy in the system, aging occurs. Essentially, aging is the phenomenon of running out of predetermined cell resources. Different species have evolved separate strategies to utilize their limited cell resources throughout their life cycle.


Assuntos
Envelhecimento , Neoplasias , Humanos , Distribuição de Poisson , Neoplasias/epidemiologia , Neoplasias/genética , Divisão Celular , Entropia
14.
Front Cardiovasc Med ; 10: 1205373, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485265

RESUMO

Background: Aortic dissection (AD) is a severe cardiovascular disease characterized by aortic rupture, aortic valve insufficiency, aortic branch lumen stenosis, and occlusion. Acute ST-segment elevation myocardial infarction may be the primary manifestation when aortic dissection affects the coronary artery, leading to delayed or missed diagnosis of aortic dissection, and preventing patients from receiving timely and comprehensive treatment. Simultaneous aortic repair and coronary artery bypass grafting surgery are controversial because of their high mortality rates. Personalized and optimal treatment plans for patients should be taken seriously based on their different conditions and treatment options. Case presentation: A 42-year-old man who experienced 1 h of persistent precordialgia was admitted to a local second-level hospital for emergency treatment. Electrocardiogram (ECG) showed evidence of ST-segment elevation, and myocardial enzyme levels were CK-MB 18.35 ng/ml and troponin 0.42 ng/ml. The patient was treated for acute myocardial infarction (AMI) and urgently sent to the interventional catheter room. Coronary angiography showed stenosis of the starting part of the right coronary artery trunk. Thus, stent implantation was performed, and the stenosis section recovered patency; however, postoperative precordialgia was not alleviated. Computed tomography angiography (CTA) revealed a type A AD. The patient was immediately transferred to a higher-level hospital, underwent emergency surgery with cardiopulmonary bypass (CPB) ascending aorta replacement, SUN's procedure (total arch replacement and stented elephant trunk implantation), and simultaneous implantation of extracorporeal membrane oxygenation (ECMO), and regained consciousness within intensive care unit care. ECMO was discontinued when hemodynamics stabilized. The patient ultimately recovered well and was discharged. Conclusion: This case demonstrated that precordialgia is not limited to myocardial infarction but may also be accompanied by aortic dissection. Percutaneous coronary intervention (PCI) can timely and effectively restore coronary artery perfusion, strive for the opportunity of aortic repair surgery, and can overcome pump failure caused by myocardial infarction, cardiopulmonary bypass, heart block time, and myocardial ischemia-reperfusion injury. Personalized treatment is crucial for patients with complex type A aortic dissection.

16.
JAMA ; 330(4): 372-373, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37418277

RESUMO

A previously healthy 7-year-old had 1 week of fevers, productive cough, and lethargy, which did not improve after 3 days of oral cefuroxime. He lived in a rural area and had close contact with dogs, cattle, and sheep. White blood cell count was 8000/µL, with 25.8% eosinophils; computed tomography showed a ruptured right upper lobe pulmonary cyst and 3 liver cysts. What is the diagnosis and what would you do next?


Assuntos
Cistos , Hepatopatias , Pneumopatias , Criança , Humanos , Cistos/etiologia , Hepatopatias/etiologia , Pneumopatias/etiologia
17.
Int Wound J ; 20(9): 3794-3801, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37350616

RESUMO

A meta-analysis research was executed to appraise the effect of platelet-rich plasma (PRP) on sternal wound healing (SWH). Inclusive literature research till April 2023 was done and 1098 interconnected researches were revised. The 11 picked researches, enclosed 8961 cardiac surgery (CS) persons were in the utilised researchers' starting point, 3663 of them were utilising PRP, and 5298 were control. Odds ratio (OR) and 95% confidence intervals (CIs) were utilised to appraise the effect of PRP on the SWH by the dichotomous approach and a fixed or random model. PRP had significantly lower sternal wound infection (SWI) (OR, 0.11; 95% CI, 0.03-0.34, p < 0.001), deep SWI (OR, 0.29; 95% CI, 0.16-0.51, p < 0.001), and superficial SWI (OR, 0.20; 95% CI, 0.13-0.33, p < 0.001), compared to control in CS persons. PRP had significantly lower SWI, deep SWI, and superficial SWI, compared to control in CS persons. However, caution must be taken when interacting with its values since there was a low sample size of some of the nominated research found for the comparisons in the meta-analysis.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Plasma Rico em Plaquetas , Humanos , Infecção da Ferida Cirúrgica/terapia , Cicatrização , Esterno/cirurgia
19.
J Chem Theory Comput ; 19(10): 3007-3021, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37115781

RESUMO

Covalent drug design is an important component in drug discovery. Traditional drugs interact with their target in a reversible equilibrium, while irreversible covalent drugs increase the drug-target interaction duration by forming a covalent bond with targeted residues and thus may offer a more effective therapeutic approach. To facilitate the design of this class of ligands, computational methods can be used to help identify reactive nucleophilic residues, frequently cysteines, on a target protein for covalent binding, to test various warhead groups for their potential reactivities, and to predict noncovalent contributions to binding that can facilitate drug-target interactions that are important for binding specificity. To further aid covalent drug design, we extended a functional group mapping approach based on explicit solvent all-atom molecular simulations (SILCS: site identification by ligand competitive saturation) that intrinsically considers protein flexibility, functional group, and protein desolvation along with functional group-protein interactions. Through docking of a library of representative warhead fragments using SILCS-Monte Carlo (SILCS-MC), reactive cysteines can be correctly identified for proteins being tested. Furthermore, a machine learning model was trained to quantify the effectiveness of various warhead groups for proteins using metrics from SILCS-MC as well as experimental model compound warhead reactivity data. The ability to rank covalent molecular binders with similar warheads using SILCS ligand grid free energy (LGFE) ranking was also tested for several proteins. Based on these tools, an integrated SILCS-based workflow was developed, named SILCS-Covalent, which can both qualitatively and quantitatively inform covalent drug discovery.


Assuntos
Desenho de Fármacos , Proteínas , Ligantes , Fluxo de Trabalho , Proteínas/química , Sítios de Ligação
20.
J Mol Graph Model ; 118: 108354, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36209593

RESUMO

In order to research the effect pattern of MnS inclusions on free-cutting steel, we study the microstructure evolution, the damage mechanism and the mechanical properties in free-cutting steel in the presence of MnS inclusions. Spindle shaped MnS is added as inclusions within the free-cutting steel. The mechanical properties were found to change when inclusions were present. The gained results show that the formation of voids causing fracture starts from the interface inside the matrix close to the MnS. From the point of view of nanocomposite strength, the main effect of MnS inclusions is related to stress concentration, leading to the effect of increased stresses near the interface between the interior of the matrix and the inclusions. The inclusions have lower Young's modulus and lower dislocation activity, resulting in smaller deformation of the alloy system, larger interfacial stress concentrations and earlier hole formation. The maximum strain and stress regions of the alloy also appear near the MnS inclusions, which leads to the formation of defects near the MnS inclusions and then fracture of the alloy. MnS inclusions adversely affect the tensile properties of the alloy, such as Young's modulus, yield stress and yield strain. By comparing the stress-strain curves of single crystal iron and alloy containing MnS inclusions, it is indicated that the yield strength of the latter decreases. Slip bands and dislocation lines are first generated around the MnS inclusion, and the phase transition is induced from the original single BCC structure to FCC, HCP and amorphous structures, and the atoms of FCC, HCP and amorphous structures increase with increasing strain, while those of BCC structure decrease, especially after yield strain. This study is significant for understanding the effect of inclusions on the mechanical laws and fracture mechanisms of the alloy.

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