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Ytterbium(III) reagent supported on ion exchange resin is applied to the multicomponent condensation reactions under solvent-free conditions. One-pot synthesis of a library of 3,4-dihydropyrimidine-2(1H)-thiones and quinazolin-4(3H)-ones were described. The advantages of easy separation and recyclability of the catalysts were demonstrated. [ABSTRACT FROM AUTHOR]

In the presence of 10 mol% of La(O-i-Pr)3, a three-component condensation reaction of aldehyde, secondary amine and trimethylsilylcyanide proceeded smoothly to afford N,N-dialkyl-α-cyanoamine in good yield. [ABSTRACT FROM AUTHOR]

Various 4-substituted-1-methyltetrahydroquinolines are easily accessible from the one-pot condensation reaction of N-methylaniline with commercial formaldehyde solution and electron-rich alkenes in the presence of Dy(OTf)3 (1 mol %) under mild conditions at ambient temperature and in the absence of any organic solvents. [ABSTRACT FROM AUTHOR]

High-grade serous ovarian cancer (HGSOC) is the most common type of epigenetically heterogeneous ovarian cancer. Methylation typing has previously been used in many tumour types but not in HGSOC. Methylation typing in HGSOC may promote the development of personalized care. The present study used DNA methylation data from The Cancer Genome Atlas database and identified four unique methylation subtypes of HGSOC. With the poorest prognosis and high frequency of residual tumours, cluster 4 featured hypermethylation of a panel of genes, which indicates that demethylation agents may be tested in this group and that neoadjuvant chemotherapy may be used to reduce the possibility of residual lesions. Cluster 1 and cluster 2 were significantly associated with metastasis genes and metabolic disorders, respectively. Two feature CpG sites, cg24673765 and cg25574024, were obtained through Cox proportional hazards model analysis of the CpG sites. Based on the methylation level of the two CpG sites, the samples were classified into high- and low-risk groups to identify the prognostic information. Similar results were obtained in the validation set. Taken together, these results explain the epigenetic heterogeneity of HGSOC and provide guidance to clinicians for the prognosis of HGSOC based on DNA methylation sites. [ABSTRACT FROM AUTHOR]

Aims: Sphingosine-1-phosphate receptor 2 (S1PR2) is a G-protein-coupled receptor that regulates sphingosine-1-phosphate-triggered cellular response. However, the role of S1PR2 in diabetes-induced glomerular endothelial cell dysfunction remains unclear. This study aims to investigate the effect of S1PR2 blockade on the morphology and function of mitochondria in human renal glomerular endothelial cells (HRGECs).Methods: HRGECs were pretreated with a S1PR2 antagonist (JTE-013) or a Rho-associated coiled coil-containing protein kinase 1 (ROCK1) inhibitor (Y27632) for 30 min and then cultured with normal glucose (5.5 mM) or high glucose (30 mM) for 72 h. The protein expression levels of RhoA, ROCK1, and Dynmin-related protein-1(Drp1) were evaluated by immunoblotting; mitochondrial morphology was observed by electron microscopy; intracellular levels of ATP, ROS, and Ca2+ were measured by ATPlite, DCF-DA, and Rhod-2 AM assays, respectively. Additionally, the permeability, apoptosis, and migration of cells were determined to evaluate the effects of S1PR2 and ROCK1 inhibition on high glucose-induced endothelial dysfunction.Results: High glucose induced mitochondrial fission and dysfunction, indicated by increased mitochondrial fragmentation, ROS generation, and calcium overload but decreased ATP production. High glucose also induced endothelial cell dysfunction, indicated by increased permeability and apoptosis but decreased migration. However, inhibition of either S1PR2 or ROCK1 almost completely blocked these high glucose-mediated cellular responses. Furthermore, inhibiting S1PR2 resulted in the deceased expression of RhoA, ROCK1, and Drp1 while inhibiting ROCK1 led to the downregulated expression of Drp1.Conclusions: S1PR2 antagonist modulates the morphology and function of mitochondria in HRGECs via the positive regulation of the RhoA/ROCK1/Drp1 signaling pathway, suggesting that the S1PR2/ROCK1 pathway may play a crucial role in high glucose milieu. [ABSTRACT FROM AUTHOR]

Periostin (POSTN) overexpression observed in various cancer types is correlated with metastasis and tumor progression. However, its effect on the crosstalk between ovarian cancer cells and cancer-associated fibroblasts (CAFs) remains elusive. This study aims to ascertain the role of CAF-derived POSTN in the ovarian cancer microenvironment. POSTN expression in high-grade serous ovarian cancer (HGSC) was detected through immunochemistry. Transwell assay was conducted to determine cell migration and invasion. POSTN was knocked down or overexpressed using lentiviral vectors. The potential downstream effects of POSTN were explored and verified by RNA sequencing and western blotting, respectively. In vitro metastatic capability of ovarian cancer cells regulated by POSTN was determined by indirect co-culture. POSTN was highly enriched in HGSC stromal components, particularly in fibroblasts, while its overexpression was correlated with reduced overall survival (OS). CAF-derived POSTN functioned as a ligand for integrin αvβ3, fueling the migration and invasion of ovarian cancer cells by activating the PI3K/Akt pathway and inducing the epithelial-mesenchymal transition (EMT). Additionally, the pro-metastatic properties and the activation of fibroblasts induced by TGF-β1 partly relied on POSTN. Stromal-derived POSTN drives the remodeling of the pro-metastatic microenvironment, which might be as a potential therapeutic target in patients with ovarian cancer. • POSTN is overexpressed in ovarian cancer stroma, especially in activated fibroblasts. • CAF-derived POSTN promotes ovarian cancer metastasis through integrin-mediated activation of PI3K/Akt pathway. • Fibroblast activation and its pro-metastatic properties induced by TGF-β1 are partly relied on POSTN. [ABSTRACT FROM AUTHOR]

In this paper, we investigate CSS-quasinormality of maximal subgroups of Sylow subgroups of some Fitting subgroup and obtain a sufficient condition about the supersolvablity of finite groups, such that some known results about c-normality and SS-quasinormality are generalized and unified. [ABSTRACT FROM AUTHOR]

Background: The clinical significance of hematogenous and lymphatic metastasis in ovarian cancer has been increasingly addressed, as it plays an imperative role in the formation of both intraperitoneal and distant metastases. Our objective is to identify the key molecules and biological processes potentially related to this relatively novel metastatic route in serous ovarian cancer.Methods: Since lymphovascular space invasion (LVSI) is considered as the first step of hematogenous and lymphatic dissemination, we developed a gene signature mainly based on the transcriptome profiles with available information on LVSI status in the Cancer Genome Atlas (TCGA) dataset. We then explored the underlying biological rationale and prognostic value of the identified gene signature using multiple public databases.Results: We observe that primary tumors with increased risk of hematogenous and lymphatic metastasis highly express a panel of genes, namely POSTN, LUM, THBS2, COL3A1, COL5A1, COL5A2, FAP1 and FBN1. The identified geneset is characterized by enhanced deposition of extracellular matrix and extensive stromal activation. Mechanistically, both the recruitment and the activation of stromal cells, especially fibroblasts, are closely associated with lymphovascular metastasis. Survival analysis further reveals that the elevated expression of the identified genes correlates to cancer progression and poor prognosis in patients with serous ovarian cancer.Conclusions: Our findings indicate that tumor stroma supports the hematogenous and lymphatic spread of ovarian cancer, increasing tumor invasiveness and ultimately resulting in worse survival. Thus stroma-targeted therapies may improve the clinical outcomes in combination with cytoreductive surgery and chemotherapy. [ABSTRACT FROM AUTHOR]

To explore the differences in clinicopathological characteristics and prognosis between seromucinous borderline ovarian tumors (SMBOTs) and mucinous borderline ovarian tumors (MBOTs). Ninety-one patients with SMBOTs and MBOTs who underwent surgery at the Obstetrics and Gynecology Hospital of Fudan University from July 2006 to January 2015 were included. The median onset age of patients with SMBOTs (29 years, 20–77) was younger than that of patients with MBOTs (37 years, 16–71). SMBOTs were more likely to be exogenous and show bilateral ovarian involvement and had a smaller average tumor size of 10.63 cm, while MBOTs were more prone to endogenous growth and show unilateral involvement and had a larger average tumor size of 18.55 cm (p < 0.05). Compared with MBOTs, SMBOTs were characterized by the expression of Mullerian differentiation markers (p < 0.05). Recurrence occurred in 15.8% patients with SMBOT and 9.1% patients with MBOT. One case of SMBOT (2.6%) and one case of MBOT (2.3%) progressed to malignancy during follow-up, but no disease-related death was observed. Age less than 40 years was a risk factor for recurrence, while the effect of fertility-sparing surgery (FSS) on recurrence requires a larger sample size to be validated. The clinical characteristics of SMBOTs and MBOTs are similar but also quite different. High expression of Mullerian differentiation markers in SMBOT may indicate a better response to hormone therapy. Repeated FSS should be performed with caution and fully informed because of the risk of recurrence and progression to malignancy. [ABSTRACT FROM AUTHOR]

Vascular complications are the main cause of morbidity and mortality associated with type 2 diabetes mellitus. An early hallmark of the onset of vascular complications is endothelial dysfunction and apoptosis. We aimed to explore the role of sphingosine-1-phosphatereceptor 2 (S1PR2) in high glucose-induced endothelial cells apoptosis and to elaborate the underlying mechanism. Human umbilical vein endothelial cells (HUVECs) were cultured in a high glucose with or without S1PR2 antagonist. The apoptosis of the cells was measured by flow cytometry and mitochondrial membrane permeability was detected by the fluorescent probe JC-1. The expression of the related protein was determined by western blot. Cell apoptosis and the loss of mitochondrial membrane permeability were induced under high glucose conditions in HUVECs. The expression of mitochondrial apoptosis related protein bax increased and bcl-2 decreased in high glucose-induced HUVECs. The level of cytochrome c released into the cytoplasm increased when cells were exposed to high glucose. In addition, the expression of p-AKT and p-GSK3β was reduced when HUVECs were treated with high glucose. However, these effects were reversed in HUVECs when cells treated with S1PR2 antagonist. In conclusion, S1PR2 antagonist protects endothelial cells against high glucose-induced mitochondrial apoptosis through the Akt/GSK-3β signaling pathway. [ABSTRACT FROM AUTHOR]

Streptococcus iniae is a worldwide fish pathogen that cause tremendous economic losses to the global aquaculture industry. Vaccination is regarded as the most effective and safe way to control fish diseases. In our study, we developed a formalin-inactivated vaccine against S. iniae and evaluated its effect in golden pompano (Trachinotus ovatus). In addition, in order to clarify the molecular mechanisms underlying the vaccine protection, we compared the spleen transcriptomes of vaccinated and unvaccinated golden pompano at 1, 2 and 7 d post vaccination using the RNA-seq technology. The relative percentage survival (RPS) reached 71.1% at 28 days post-vaccination which suggested that the vaccine provided highly protection against S. iniae. KEGG pathway analysis revealed that phagosome, cytokine-cytokine receptor interaction, MAPK signaling pathway, and CAMs were activated by the vaccine. The most of strongly up-regulated genes in golden pompano spleen are involving in innate immunity. For adaptive immunity, the vaccine evoked a CD8+ CTL-mediated response by MHC Ⅰ pathway to achieve immune protection. • We developed a formalin-inactivated vaccine against Streptococcus iniae with a RPS of 71.1% in golden pompano. • To underlying the protective immune response of golden pompano, we analyzed the spleen transcriptomes of unvaccinated and vaccinated golden pompano at days 1, 2, and 7 after vaccination. • Immune-relevant KEGG pathways were activated by the vaccine, including phagosome, cytokine-cytokine receptor interaction, MAPK signaling pathway, and CAMs. • The vaccine evoked a CD8+ CTL-mediated response by MHC Ⅰ pathway to achieve immune protection. [ABSTRACT FROM AUTHOR]

Background: To compare the prognosis of lymphatic metastasis in type I and type II epithelial ovarian cancer (OC) and to identify the risk factors for pelvic lymph node metastases (PLNs) and para-aortic lymph node metastases (PALNs). Methods: Patients diagnosed with epithelial OC were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Overall survival (OS) and cancer-specific survival (CSS) were estimated. The Cox proportional hazards regression model was used to identify independent predictors of survival. Results: A total of 11,275 patients with OC were enrolled, including 31.2% with type I and 68.8% with type II. Type II and high tumour stage were risk factors for lymph node involvement (p < 0.05). The overall rate of lymph node metastasis in type I was 11.8%, and that in type II was 36.7%. In the type I group, the lymph node metastasis rates in stages T1, T2, T3 and TXM1 were 3.2%, 14.5%, 40.4% and 50.0%, respectively. In the type II group, these rates were 6.4%, 20.4%, 54.1% and 61.1%, respectively. Age and tumour size had little effect on lymph node metastasis, and grade 3 was not always a risk factor. For the type I group, the 10-year CSS rates of LN(-), PLN(+), PALN(+), and PLN + PALN(+) were 80.6%, 46.6%, 36.3%, and 32.3%, respectively. The prognosis of PLN (+) was better than that of PALN (+) in the type I group (p > 0.05). For the type II group, the 10-year CSS rates of LN(-), PLN(+), PALN(+), and PLN + PALN(+) were 55.6%, 18.5%, 25.7%, and 18.2%, respectively. PALN (+) had a significantly better prognosis than PLN (+) in the type II group (p < 0.05). Conclusions: The clinical characteristics and prognoses of patients with type I and type II OC differed greatly. Patients with type II and higher tumour stages had poorer prognoses. Type I with PALN metastasis and type II with PLN metastasis indicated a worse prognosis. Patients with stage TI did not require lymph node dissection, especially in the type I group. [ABSTRACT FROM AUTHOR]

The isothermal oxidation kinetic and oxidation behavior of Ni-based superalloy GH202 were investigated at temperatures from 800 °C to 1100 °C. The microstructure of GH202 was characterized by scanning electron microscope (SEM) and electron back-scattered diffraction (EBSD). The composition and morphologies of oxide scales of the surface and cross-section samples were examined by X-ray diffraction (XRD), electron probe microanalysis (EPMA), and SEM combined with energy-dispersive spectroscopy (EDS). The results show that the growth of the oxide scales on GH202 obeyed a parabolic law with an activation energy of 247.8 KJ·mol − 1 from 800 °C to 1100 °C. The continuous and dense oxide scales that formed at 800 °C and 900 °C were composed of Cr 2 O 3 , NiCr 2 O 4 and a small amount of TiO 2 . Beneath the oxide scales, aluminum-rich oxides formed along the grain boundaries due to internal oxidation. After treatment at 1000 °C for 150 h, the oxide scale was separated into two layers, the outer layer with sparse holes that was mainly composed of Cr 2 O 3 and TiO 2 and an inner layer of dense Cr 2 O 3 . At 1100 °C for 100 h the outer layer was spalled, due to the looser oxide scale with large blocks of TiO 2 and NiCr 2 O 4 which provided channels for oxygen diffusion. [ABSTRACT FROM AUTHOR]

Ferroptosis is an iron-dependent form of programmed cell death with the potential to reverse traditional cancer therapy resistance. The combination of ferroptosis with chemotherapy, photodynamic therapy and X-ray therapy has demonstrated remarkably improved therapeutic efficiency. Radiopharmaceutical therapy (RPT) is an emerging approach that achieves precise radiation to diseased tissues via radionuclide delivery. However, insufficient accumulation and retention of therapeutic radiopharmaceuticals in tumor region as well as cancer radioresistance impact treatment efficacy. Here, a nanoassembly of renal clearable ultrasmall iron nanoparticles (USINPs) and 131I-aPD-L1 is prepared via the affinity of fluorophenylboronic acid modified on the USINPs with 131I-aPD-L1. The 150 nm USINAs(131I-aPD-L1) nanoassembly is stable in blood circulation, effectively targets to the tumor and disassembles in the presence of ATP in the tumor microenvironment. Both in vitro and in vivo experiments prove that USINPs-induced ferroptosis boosted the tumor radiosensitization to 131I while 131I-mediated RPT further enhanced ferroptosis. Meanwhile, the immunogenic cell death caused by RPT and ferroptosis combined with PD-L1 immune checkpoint blockade therapy exhibits a strong antitumor immunity. This study provides a novel way to improve the tumor accumulation of ferroptosis inducer and radiopharmaceuticals, insights into the interaction between RPT and ferroptosis and an effective SPECT-guided ferroptosis-enhanced radio-immunotherapy. • This study assembled inorganic nanoparticles and antibody based radiopharmaceuticals in a single nanoplatform. • The assembly improved the tumor targeting and retention of USINPs and 131I, and maintained their bioactivity. • The study uncovers the link between ferroptosis and 131I-mediated radiopharmaceutical therapy. • USINAs(131I-aPD-L1) present an effective SPECT imaging guided ferroptosis enhanced radio-immunotherapeutic approach. [ABSTRACT FROM AUTHOR]

Background: Lymphovascular space invasion (LVSI) is the first step of hematogenous metastasis. Exploration of the differential miRNA expression profiles between LVSI-positive and LVSI-negative ovarian cancer tissues may help to identify key miRNAs involved in the hematogenous metastasis of ovarian cancer. This study is aimed to identify microRNAs (miRNAs) that are differentially expressed between LVSI-positive and LVSI-negative ovarian cancer tissues, followed by exploring their association with bevacizumab response in ovarian cancer patients. Methods: The Cancer Genome Altas (TGGA) dataset was used to identify the differentially expressed miRNAs between LVSI-positive and LVSI-negative ovarian cancer tissues. The prognostic value of the differentially expressed miRNAs was determined using GSE140082 dataset. Results: We showed that miR-25 and miR-142 were differentially expressed between LVSI-positive and LVSI-negative ovarian cancer tumors. Kaplan-Meier analysis indicated that high miR-25 expression was associated with increased progression free survival (PFS) and extended overall survival (OS). Moreover, patients with low miR-25 expression benefited significantly from bevacizumab treatment in terms of PFS. A similar trend was observed in terms of OS though without reaching statistical significance. In contrast, no significant survival benefits from bevacizumab were observed in patients with high miR-25 expression in terms of PFS and OS. There was no significant correlation between miR-142 expression and PFS. In contrast, high miR-142 expression was associated with reduced OS. Moreover, patients with high miR-142 expression benefited significantly from bevacizumab treatment in terms of PFS and OS. However, bevacizumab treatment conferred no significant improvements in both PFS and OS in patients with low miR-142 expression. The nomogram for PFS indicated that miR-25 expression had a larger contribution to PFS than debulking status and bevacizumab treatment. And the nomogram for OS illustrated both miR-25 expression and miR-142 expression as sharing a larger contribution to OS than bevacizumab treatment and debulking status. Conclusion: In conclusion, miR-25 expression correlates with a better PFS and OS in ovarian cancer. Patients with low miR-25 expression and high miR-142 expression could benefit from bevacizumab treatment significantly. [ABSTRACT FROM AUTHOR]

Objective: To enable a comparison of reported chemotherapy regimens in gestational trophoblastic neoplasia (GTN) patients with a International Federation of Gynecology and Obstetrics (FIGO) score ≥12.Study Design: Studies reporting cases of GTN with a FIGO score ≥12 were collected and screened for eligibility. A total of 17 studies encompassing 256 patients were included in final analysis.Results: In the first-line setting, etoposide-methotrexate-dactinomycin alternating with cyclophosphamide-vincristine (EMA/CO), etoposide-platinum alternating with EMA (EP/EMA), and floxuridine-dactinomycin-etoposide-vincristine (FAEV) were the three most commonly used regimens. The complete response (CR) rate was 55.2% for EMA/CO, 60.0% for EP/EMA, and 63.1% for FAEV. There was no significant difference in CR rate among EMA/CO, EP/EMA and FAEV in the first-line setting. While limited by low number, the CR rate was 66.67% for methotrexate-bleomycin -etoposide (MBE), and 25% for vincristine-dactinomycin-cyclophosphamide (VAC). Of the patients who failed initial therapy, EMA/CO, EP/EMA, and paclitaxel- cisplatin alternating with paclitaxel-etoposide (TP/TE) were the three most commonly used salvage regimens. The CR rate was 39.7% for EMA/CO, 35.0% for EP/EMA, and 11.8% for TP/TE. While limited by low number, MBE was used in 5 patients and yielded a 80% CR rate. Of the fatal cases, 21 (61.8%) patients had brain metastases, and 41.2% (14/34) of the deaths were early deaths.Conclusion: EMA/CO, EP/EMA, and FAEV yielded comparable CR rates in GTN patients with a FIGO score ≥12 in the first-line setting. [ABSTRACT FROM AUTHOR]

Routine coagulation test before intravenous tissue plasminogen activator (tPA) use increases the door to needle time (DNT). We sought to evaluate the safety of tPA use without coagulation results and its impact on prognosis. In our stroke registry, tPA was delivered with coagulation results from December 2015 to April 2016 and without coagulation results from May 2016 to December 2016. Differences of demographics, clinical characteristic, and prognosis between these two groups were analyzed. In addition, logistic regression analysis was conducted to identify predictors for DNT of over 60 min. A total of 201 stroke patients were included in the final analysis. Of these, 81 patients received tPA with coagulation results and 120 patients without coagulation results. Only one (0.8%) patient with abnormal coagulation results met the exclusion criteria of tPA use in patients without coagulation results. The difference of DNT between groups with (mean, 61.7 min) and without (mean, 41.9 min) coagulation results was significant (P = 0.00). The group without coagulation results had a higher rate of favorable 90-day outcome (74.2 vs 70.4%) and lower rates of symptomatic intracranial hemorrhage/nonintracranial hemorrhage (4.9 and 22.2% vs 1.7 and 19.2%) than the group with coagulation results did; these differences were not statistically significant. In multivariate analysis, only tPA use with coagulation results was the predictor for DNT of over 60 min (P = 0.0030, OR = 2.44, 95% CI 1.28-4.65). The present study suggests that tPA could be delivered safely without coagulation results in patients without suspected coagulopathy, and avoiding coagulation tests reduces significantly the DNT interval. [ABSTRACT FROM AUTHOR]

In this study, a combination of laser shock peening (LSP) and low-temperature annealing (LTA) was used to modulate the microstructures of Ti6Al4V, which can achieve an optimal combination of strength and plasticity. Microstructure observations showed that after LSP treatment, serious plastic deformation and grain refinement occurred. This resulted in the formation of non-equilibrium grain boundaries (GBs) composed of dislocations, twins, and martensite transformation. After LTA treatment, the dislocation density decreased as it rearranged, resulting in GB relaxation. The GB state can change from non-equilibrium to equilibrium. Additionally, LTA treatment can increase the activation energy and facilitate element diffusion from high to low concentration. The decrease in dislocation density and element diffusion results in GB with low excess energy, increasing the stability of the microstructural. The LSP composite LTA treatment showed a high tensile strength of 994 MPa and an excellent elongation of 17.4% compared to the untreated specimen. Excellent microstructure stability and mechanical properties are achieved in Ti6Al4V after combined post-treatment of LSP and LTA. • LSP could result serious plastic deformation and improve the tensile strength. • Dislocations, deformation twins and martensite transformation were induced by LSP. • LTA could induce dislocation rearrangement and achieve equilibrium grain boundary. • Element migration was found in martensite after LTA treatment. • LTA is a potential post-processing tool to increase mechanical performance. [ABSTRACT FROM AUTHOR]

Laser shock processing (LSP) is employed to improve the high temperature oxidation resistance of Ni-based superalloy GH202. Many crystal defects of the surface after treated were found by transmission electron microscope. The residual compressive stress (maximum −305 MPa) and the micro-hardness (maximum 579 HV) of specimens treated were improved significantly. The isothermal oxidation kinetics of GH202 before and after LSP showed that the weight gain of all the treated specimens slowed relatively, and it was more obviously at 900 °C. The oxidation film of the LSP-treated GH202 was mainly composed of Cr 2 O 3 , TiO 2 , NiCr 2 O 4 and a little of Al 2 O 3 . High density dislocations provided many channels of Cr 3+ diffusing to the surface of the LSP-treated GH202, which would facilitate formation of a denser protective oxidation film compared to untreated specimens. The results showed that the high temperature oxidation resistance of the LSP-treated GH202 was improved, especially more significantly at 900 °C. [ABSTRACT FROM AUTHOR]

The microstructures and isothermal oxidation behaviors of the CoCrAlYTSi coating prepared by plasma spaying on the surface of the Ni-based superalloy GH202 were investigated. The cross-sectional sheet of the coating was prepared by focused ion beam (FIB) and the resulting microstructures were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). After oxidization at 800 °C to 1000 °C for 100 h, complex oxides were formed on the coating surface. The oxides included Al 2 O 3 , Cr 2 O 3 , CoO, CoCr 2 O 4 , Ta 2 O 5 , and SiO 2 . The protective oxidation films of Al 2 O 3 formed readily on the coating due to the higher affinity of aluminum and oxygen. The addition of yttrium can increase the fineness of the coating microstructures and improve the adhesion of the coating. The oxidation of tantalum in the coating reduces the oxygen partial pressure in the oxidation scales and accelerates the formation of Al 2 O 3 . The addition of silicon element at less than 3 wt.% can slow the oxidation rate of the CoCrAlYTaSi coating, enhance the oxide scale adherence, and prevent outward diffusion of refractory elements (such as W and Mo) from the substrate. Overall, the presence of yttrium, tantalum, and silicon in the coating improved the resistance of high temperature oxidation and enhanced the bonding force of the coating and the alloy. [ABSTRACT FROM AUTHOR]