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BACKGROUND: In the past few decades, researchers have made promising progress, including the development of immune checkpoint inhibitors (ICIs) in the therapy of bladder cancer (BLCA). Existing studies mainly focus on single immune checkpoint inhibitors but lack relevant studies on the gene expression profiles of multiple immune checkpoints. METHODS: RNA-sequencing profiling data and clinical information of BLCA patients and normal human bladder samples were acquired from the Cancer Genome Atlas and Gene Expression Omnibus databases and analyzed to identify different expression profiles of immune checkpoint genes (ICGs) after consensus clustering analysis. Based on the 526 intersecting differentially expressed genes, the LASSO Cox regression analysis was utilized to construct the ICG signature. RESULTS: According to the expression of ICGs, BLCA patients were divided into three subtypes with different phenotypic and mechanistic characteristics. Furthermore, the developed ICG signature were independent predictors of outcome in BLCA patients, and was correlated with the immune infiltration, the expression of ICGs and chemotherapeutic effect. CONCLUSIONS: This study systematically and comprehensively analyzed the expression profile of immune checkpoint genes, and established the ICG signature to investigate the differences in ICGs expression and tumor immune microenvironment, which will help risk stratification and accelerate precision medicine. Finally, we identified KRT23 as the most critical model gene, and highlighted KRT23 as a potential target to enhance immunotherapy against BLCA.
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Microambiente Tumoral , Neoplasias de la Vejiga Urinaria , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biomarcadores de Tumor/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Proteínas de Punto de Control Inmunitario/genética , Proteínas de Punto de Control Inmunitario/metabolismo , Inmunoterapia/métodos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Pronóstico , Transcriptoma , Microambiente Tumoral/inmunología , Microambiente Tumoral/genética , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/inmunología , Neoplasias de la Vejiga Urinaria/terapia , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Queratinas Tipo I/genética , Queratinas Tipo I/metabolismoRESUMEN
TBX6 encodes transcription-factor box 6, a transcription factor critical to paraxial mesoderm segmentation and somitogenesis during embryonic development. TBX6 haploinsufficiency is believed to drive the skeletal and kidney phenotypes associated with the 16p11.2 deletion syndrome. Heterozygous and biallelic variants in TBX6 are associated with vertebral and rib malformations (TBX6-associated congenital scoliosis) and spondylocostal dysostosis, and heterozygous TBX6 variants are associated with increased risk of genitourinary tract malformations. Combined skeletal and kidney phenotypes in individuals harboring heterozygous or biallelic TBX6 variants are rare. Here, we present seven individuals with vertebral and rib malformations and structural kidney differences associated with heterozygous TBX6 gene deletion in trans with a hypomorphic TBX6 allele or biallelic TBX6 variants. Our case series highlights the association between TBX6 and both skeletal and kidney disease.
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Osteocondrodisplasias , Escoliosis , Humanos , Proteínas de Dominio T Box/genética , Escoliosis/genética , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/anomalías , Fenotipo , Factores de Transcripción/genética , Túbulos Renales ProximalesRESUMEN
The parking problem, which is caused by a low parking space utilization ratio, has always plagued drivers. In this work, we proposed an intelligent detection method based on deep learning technology. First, we constructed a TensorFlow deep learning platform for detecting vehicles. Second, the optimal time interval for extracting video stream images was determined in accordance with the judgment time for finding a parking space and the length of time taken by a vehicle from arrival to departure. Finally, the parking space order and number were obtained in accordance with the data layering method and the TimSort algorithm, and parking space vacancy was judged via the indirect Monte Carlo method. To improve the detection accuracy between vehicles and parking spaces, the distance between the vehicles in the training dataset was greater than that of the vehicles observed during detection. A case study verified the reliability of the parking space order and number and the judgment of parking space vacancies.
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Algoritmos , Redes Neurales de la Computación , Humanos , Reproducibilidad de los Resultados , ComputadoresRESUMEN
Currently, deep learning has been widely applied in the field of object detection, and some relevant scholars have applied it to vehicle detection. In this paper, the deep learning EfficientDet model is analyzed, and the advantages of the model in the detection of hazardous good vehicles are determined. The adaptive training model is built based on the optimization of the training process, and the training model is used to detect hazardous goods vehicles. The detection results are compared with Cascade R-CNN and CenterNet, and the results show that the proposed method is superior to the other two methods in two aspects of computational complexity and detection accuracy. Simultaneously, the proposed method is suitable for the detection of hazardous goods vehicles in different scenarios. We make statistics on the number of detected hazardous goods vehicles at different times and places. The risk grade of different locations is determined according to the statistical results. Finally, the case study shows that the proposed method can be used to detect hazardous goods vehicles and determine the risk level of different places.
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Aprendizaje Profundo , Redes Neurales de la Computación , Algoritmos , Recolección de Datos/métodosRESUMEN
As the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas12a (previously known as Cpf1) system cleaves double-stranded DNA and produces a sticky end, it could serve as a useful tool for DNA assembly/editing. To broaden its application, a variety of engineered FnCas12a proteins are generated with expanded protospacer adjacent motif (PAM) requirements. Two variants (FnCas12a-EP15 and EP16) increased the targeting range of FnCas12a by approximately fourfold. They can efficiently recognize a broad range of PAM sequences including YN (Y = C or T), TAC and CAA. Meanwhile, based on our demonstration that FnCas12a is active from 16 to 60°C, we developed an "improved CRISPR-Cas12a-assisted one-pot DNA editing" (iCOPE) method to facilitate DNA editing by combining the crRNA transcription, digestion, and ligation in one pot. By applying iCOPE, the editing efficiency reached 72-100% for two DNA fragment assemblies, and for the 21 kb large DNA construct modification, the editing efficiency can reach 100%. Thanks to the advantages of Cas12a, iCOPE with only one digestion enzyme could replace current a variety of restriction enzymes to perform the cloning in one pot with almost no sequence constraints. Taken together, this study offers an expanded DNA targeting scope of CRISPR systems and could serve as an efficient seamless one-pot DNA editing tool.
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Proteínas Bacterianas/genética , Proteínas Asociadas a CRISPR/genética , Sistemas CRISPR-Cas , ADN/genética , Endodesoxirribonucleasas/genética , Edición Génica/métodos , Clonación Molecular , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Escherichia coli/genética , Proteínas Luminiscentes/genética , Modelos Moleculares , Plásmidos/genética , Ingeniería de ProteínasRESUMEN
Background: The disulfide stress-induced cell death known as disulfidptosis is characterized by the disintegration of cytoskeletal proteins and F-actin as a result of an excessive buildup of disulfides within the cell. The relationship between disulfidptosis-associated long non-coding RNA (lncRNA) in hepatocellular carcinoma (HCC) progression is still not clearly understood. In this article, we aim to explore the crucial role of lncRNA in HCC. Methods: We initially obtained lncRNA related to HCC and clinical data from TCGA. The genes associated with disulfidptosis were identified through co-expression analysis, Cox regression, and Lasso regression. Additionally, we established a prognostic model for verification. Results: The risk model constructed with disulfidptosis-related lncRNA has been confirmed to be a good predictor of high and low-risk groups of HCC patients through survival curves, independent prognostic analysis, concordance index (C-index), ROC curves, and Kaplan-Meier plots. We also discovered differences in the response to immune targets and anticancer drugs between the two groups of patients, with GDC0810, Osimertinib, Paclitaxel, and YK-4-279 being more effective for patients in the high-risk group. Conclusion: In conclusion, we have developed a risk model that can guide future efforts to diagnose and treat HCC.
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Robust, sensitive, and rapid molecular detection tools are essential prerequisites for disease diagnosis and epidemiological control. However, the current mainstream tests necessitate expensive equipment and specialized operators, impeding the advancement of molecular diagnostics. The CRISPR-Cas system is an integral component of the bacterial adaptive immune system, wherein Cas proteins recognize PAM sequences by binding to CRISPR RNA, subsequently triggering DNA or RNA cleavage. The discovery of the CRISPR-Cas system has invigorated molecular diagnostics. With further in-depth research on this system, its application in molecular diagnosis is flourishing. In this review, we provide a comprehensive overview of recent research progress on the CRISPR-Cas system, specifically focusing on its application in molecular diagnosis.
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Sistemas CRISPR-Cas , Sistemas CRISPR-Cas/genética , Humanos , Patología Molecular/métodos , Técnicas de Diagnóstico MolecularRESUMEN
Background: Congenital scoliosis and congenital anomalies of the kidney and urinary tract are distinct genetic disorders with differing clinical manifestations. Clinically, their coexistence is not rare, but the etiologies of these complex diseases remain largely unknown, especially their shared genetic basis. Methods: We sequenced the genomes of 40 individuals diagnosed with both CS and CAKUT, alongside 2,764 controls from a Chinese Han population cohort. Our analyses encompassed gene-based and pathway-based weighted rare variant association tests, complemented by copy number variant association analyses, aiming to unravel the shared genomic etiology underlying these congenital conditions. Results: Gene-based analysis identified PTPN11 as a pivotal gene influencing both skeletal and urinary system development (P = 1.95E-21), participating in metabolic pathways, especially the MAPK/ERK pathway known to regulate skeletal and urinary system development. Pathway-based enrichment showed a significant signal in the MAPK/ERK pathway (P = 3E-04), reinforcing the potential role of PTPN11 and MAPK/ERK pathway in both conditions. Additionally, CNV analysis pinpointed IGFLR1 haploinsufficiency as a potential influential factor in the combined CS-CAKUT phenotypic spectrum. Conclusion: This study enriches our understanding of the intricate genomic interplay underlying congenital scoliosis and kidney and urinary tract anomalies, emphasizing the shared genetic foundations between these two disorders.
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In hepatocellular carcinoma (HCC), immunotherapy is vital for advanced-stage patients. However, diverse individual responses and tumor heterogeneity have resulted in heterogenous treatment outcomes. Our mechanistic investigations identified LAPTM4B as a crucial gene regulated by ETV1 (a transcription factor), especially in liver cancer stem cells (LCSCs). The influence of LAPTM4B on LCSCs is mediated via the Wnt1/c-Myc/ß-catenin pathway. CXCL8 secretion by LAPTM4B drove myeloid-derived suppressor cell (MDSC) migration, inducing unfavorable patient prognosis. LAPTM4B affected PD-L1 receptor expression in tumor microenvironment and enhanced tumor suppression induced by PD-L1 monoclonal antibodies in HCC patients. LAPTM4B up-regulation is correlated with adverse outcomes in HCC patients, sensitizing them to PD-L1 monoclonal antibody therapy.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Células Supresoras de Origen Mieloide , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Células Supresoras de Origen Mieloide/metabolismo , Antígeno B7-H1/genética , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Factores de Transcripción , Inmunoterapia/métodos , Proliferación Celular , Microambiente Tumoral , Proteínas de la Membrana/metabolismo , Proteínas Oncogénicas/metabolismoRESUMEN
Glycogen metabolism is a form of crucial metabolic reprogramming in cells. PYGB, the brain-type glycogen phosphorylase (GP), serves as the rate-limiting enzyme of glycogen catabolism. Evidence is mounting for the association of PYGB with diverse human diseases. This review covers the advancements in PYGB research across a range of diseases, including cancer, cardiovascular diseases, metabolic diseases, nervous system diseases, and other diseases, providing a succinct overview of how PYGB functions as a critical factor in both physiological and pathological processes. We present the latest progress in PYGB in the diagnosis and treatment of various diseases and discuss the current limitations and future prospects of this novel and promising target.
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Glucógeno Fosforilasa , Glucógeno , Humanos , Glucógeno/metabolismo , Encéfalo/metabolismoRESUMEN
Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. The discovery and research of effective biomarkers have become prevailing trends. SUMO-activating enzyme subunit 1 (sae1), an E1-activating enzyme, is indispensable for protein SUMOylation. In this study, we conducted a comprehensive analysis of database contents and found that sae1 is highly expressed in HCC and is correlated with poor prognosis. We also identified its regulated transcription factor, rad51, and related signaling pathways. We conclude that sae1 is a promising cancer metabolic biomarker with diagnostic and prognostic value in HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/diagnóstico , Detección Precoz del Cáncer , Biomarcadores de Tumor , Transducción de Señal , PronósticoRESUMEN
Salidroside (Sal) contains anti-carcinogenic, anti-hypoxic, and anti-inflammatory pharmacological activities. However, its underlying anti-breast cancer mechanisms have been only incompletely elucidated. Hence, this protocol intended to decode the potential of Sal in regulating the PI3K-AKT-HIF-1α-FoxO1 pathway in the malignant proliferation of human breast cancer MCF-7 cells. First, the pharmacological activity of Sal against MCF-7 was evaluated by CCK-8 and cell scratch assays. Moreover, the resistance of MCF-7 cells was measured by migration and Matrigel invasion assays. For cell apoptosis and cycle assays, MCF-7 cells were processed in steps with annexin V-FITC/PI and cell cycle-staining detection kits for flow cytometry analyses, respectively. The levels of reactive oxygen species (ROS) and Ca2+ were examined by DCFH-DA and Fluo-4 AM immunofluorescence staining. The activities of Na+-K+-ATPase and Ca2+-ATPase were determined using the corresponding commercial kits. The protein and gene expression levels in apoptosis and the PI3K-AKT-HIF-1α-FoxO1 pathway were further determined using western blot and qRT-PCR analyses, respectively. We found that Sal treatment significantly restricted the proliferation, migration, and invasion of MCF-7 cells with dose-dependent effects. Meanwhile, Sal administration also dramatically forced MCF-7 cells to undergo apoptosis and cell cycle arrest. The immunofluorescence tests showed that Sal observably stimulated ROS and Ca2+ production in MCF-7 cells. Further data confirmed that Sal promoted the expression levels of pro-apoptotic proteins, Bax, Bim, cleaved caspase-9/7/3, and their corresponding genes. Consistently, Sal intervention prominently reduced the expression of the Bcl-2, p-PI3K/PI3K, p-AKT/AKT, mTOR, HIF-1α, and FoxO1 proteins and their corresponding genes. In conclusion, Sal can be used as a potential herb-derived compound for treating breast cancer, as it may reduce the malignant proliferation, migration, and invasion of MCF-7 cells by inhibiting the PI3K-AKT-HIF-1α-FoxO1 pathway.
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Neoplasias de la Mama , Proteínas Proto-Oncogénicas c-akt , Humanos , Femenino , Células MCF-7 , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Neoplasias de la Mama/patología , Apoptosis , Proliferación CelularRESUMEN
BACKGROUND: The dysregulation of the dopamine system contributes to depressive-like behaviors in rats, and the neurological functions regulated by hypocretin are severely affected in depression. However, whether suvorexant plays a role in alleviating depression by affecting the dopamine system is unclear. METHODS: To preliminarily explore the mechanism of suvorexant (10 mg/kg) in the treatment of depression, the mRNA and protein expression of TH, Drd2, Drd3, GluN2A, DAT, and GluN2B in the striatum of rats was quantified by qPCR and western blotting. The plasma hypocretin-1 and dopamine levels and the striatal dopamine levels were determined by ELISA. RESULTS: i) Compared to those of the control group, chronic unpredictable mild stress (CUMS) rats showed depressive-like behaviors, which were subsequently reversed by treatment with suvorexant. ii) The mRNA and protein expressions of TH, Drd2, Drd3, GluN2A, and GluN2B in the striatum of CUMS were significantly increased compared with those in the controls, but decreased after suvorexant treatment. iii) Compared with those in the control group, the plasma and striatal dopamine levels of CUMS decreased while plasma hypocretin-1 levels increased, which was reversed after suvorexant treatment. LIMITATIONS: i) The suvorexant is a dual hypocretin receptor antagonist; however, the responsible receptor is unclear. ii) We only focused on related factors in the striatum but did not explore other brain regions, nor did we directly explore the relationship among these factors. CONCLUSION: Depressive-like behaviors induced by CUMS can be reversed by suvorexant, and the therapeutic effects of suvorexant may be mediated by affecting the dopamine system.
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Depresión , Dopamina , Animales , Ratas , Depresión/tratamiento farmacológico , Depresión/metabolismo , Modelos Animales de Enfermedad , Dopamina/metabolismo , Hipocampo/metabolismo , Orexinas/metabolismo , Ratas Sprague-Dawley , ARN Mensajero/metabolismo , Estrés Psicológico/metabolismoRESUMEN
PURPOSE: To perceive the dental undergraduate's policy of coping with online learning and their decision-making laws during the COVID-19 pandemic. METHODS: For dental undergraduate students from the 2016 grade to 2018 grade of Lishui University, two prospective questionnaire surveys were conducted before the online course starting and four weeks later. SPSS Modeler18.0 software was used to screen, review, and analyze the data. TAN (tree augmented naive) Bayesian network models were utilized to analyze and predict variables. Indicators like the overall prediction accuracy, receiver operating characteristic curve (ROC curve), and area under the ROC curve(AUC value) were applied to evaluate the model's predicting performances. RESULTS: The case score of each survey was 422 and 382, and the Cronbach's α coefficients of internal consistency were 0.91 and 0.82. Among the decision-making variables in the aspect of "whether to preview online learning materials", the top-two variables were "looking forward to the semester beginning" and "the validity of the network materials". In speaking of "whether the online courses meet the offline course standards", the top-three variables were "the rhythm of lecturing on live or in recorded videos", "how many online tasks', and" the data frame and organization". The overall prediction accuracy of each constructed TAN Bayesian network model was 89.42% and 87.82%, and their AUC values were 0.75 and 0.93, respectively. CONCLUSIONS: To truly make online courses comparable to the off-line curriculum, teachers should fully understand how the students cope with their online learning at first. Then, only by perceiving and recognizing the students' expectations for education, by efficiently preparing and organizing online materials with all-round, clearly-structured, vivid, comprehensible contents and moderate difficult tasks, by well interacting with students through different websites and social media, can we truly achieve " ongoing learning with suspended class".
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COVID-19 , Educación a Distancia , Humanos , Teorema de Bayes , Toma de Decisiones , Pandemias , Estudios Prospectivos , SARS-CoV-2 , EstudiantesRESUMEN
INTRODUCTION: Correct implant positioning is required to achieve adequate biomechanics. The greater trochanter is more medially or laterally positioned in some patients, known as trochanteric lateroversion. However, studies have not identified correlations between postoperative coronal alignment and variation in greater trochanteric lateroversion. The purpose of this study was to identify the effects of variation in greater trochanteric lateroversion on postoperative stem coronal alignment and to investigate other factors related to stem coronal alignment. METHODS: A total of 213 hips in 149 patients who underwent total hip arthroplasty were included in this prospective study. The greater trochanters were categorised into 5 groups according to the degree of variation in greater trochanteric lateroversion, and the stem coronal alignment angle and stem fit were measured on anteroposterior radiographs. RESULTS: Postoperative stem varus was positively correlated with greater trochanteric lateroversion (r = 0.26065, p = 0.0001) and negatively correlated with the stem fit (r = -0.16568, p = 0.0155). DISCUSSION: Excessive variation in greater trochanteric lateroversion was a risk factor for femoral stem varus, and the stem varus position was always accompanied by inadequate canal filling. When the tip of the trochanteric overhang exceeded the centreline of the femoral canal, the influence of lateroversion of the greater trochanter on the femoral stem remarkably increased. Appropriate measures should be implemented to avoid a stem varus position and inappropriate stem fit.
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Artroplastia de Reemplazo de Cadera/efectos adversos , Fémur/cirugía , Osteoartritis de la Cadera/cirugía , Complicaciones Posoperatorias , Adulto , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/diagnóstico , Estudios Prospectivos , Radiografía , Factores de RiesgoRESUMEN
BACKGROUND: Acute aortic dissection (AAD) is a devastating cardiovascular disease with a high rate of disability and mortality. This disease often rapidly progresses to fatal multiple organ hypoperfusion, and the incidence has been increasing in recent years. However, the molecular mechanisms have yet to be clarified. This study is aimed at identifying the differential abundance proteins (DAPs) of aortic arch tissues in patients with AAD by proteomics and select possible proteins involved in AAD pathogenesis. METHODS: The fresh aortic arch tissues obtained from 5 AAD patients and 1 healthy donor were analyzed by amine-reactive tandem mass tag (TMT) labelling and mass spectrometry; then, the pathological sections of another 10 healthy donors and 20 AAD patients were chosen to verify the proteomic results by immunohistochemistry. RESULTS: Of 809 proteins identified by proteomic analysis, 132 differential abundance proteins (DAPs) were screened, of which 100 proteins were significantly downregulated while 32 upregulated. Among 100 downregulated proteins, two proteins with known function, integrin alpha 3 (ITGA-3) and ITGA-5, were selected as target proteins involved in AAD pathogenesis. Two target DAPs were verified by immunohistochemisty, and the results showed that the integrated option density (IOD) of ITGA-3 and ITGA-5 in AAD patients was significantly lower than that in healthy donors, which were consistent with the proteomic results (P < 0.001). CONCLUSION: ITGA-3 and ITGA-5 represent novel biomarkers for the pathogenesis of AAD and might be a therapeutic target in the future.
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Aneurisma de la Aorta/genética , Disección Aórtica/genética , Enfermedades Cardiovasculares/genética , Integrina alfa3/genética , Integrinas/genética , Disección Aórtica/patología , Aorta Torácica/metabolismo , Aorta Torácica/patología , Aneurisma de la Aorta/patología , Biomarcadores/sangre , Enfermedades Cardiovasculares/patología , Femenino , Regulación de la Expresión Génica/genética , Humanos , Masculino , Espectrometría de Masas , Proteoma/genéticaRESUMEN
Neurological complications are very common after liver transplantation. This study focuses on clinical risk factors and susceptibility gene polymorphisms of neurological complications after liver transplantation. A better predictive model is obtained. This study proves that MTRR is an independent susceptibility gene for neurological complications. Compared with the independent risk factor of abdominal infection, MTRR has a more advantageous value in predicting neurological complications after liver transplantation.
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To solve the lack of wear resistance of titanium alloys for use in biological applications, various prepared coatings on titanium alloys are often used as wear-resistant materials. In this paper, TiC bioinert coatings were fabricated on Ti6Al4V by laser cladding using mixed TiC and ZrO2 powders as the basic pre-placed materials. A certain amount of CeO2 powder was also added to the pre-placed powders to further improve the properties of the TiC coatings. The effects of CeO2 additive on the phase constituents, microstructures and wear resistance of the TiC coatings were researched in detail. Although the effect of CeO2 on the phase constituents of the coatings was slight, it had a significant effect on the microstructure and wear resistance of the coatings. The crystalline grains in the TiC coatings, observed by a scanning electron microscope (SEM), were refined due to the effect of the CeO2. With the increase of CeO2 additive content in the pre-placed powders, finer and more compact dendrites led to improvement of the micro-hardness and wear resistance of the TiC coatings. Also, 5 wt % content of CeO2 additive in the pre-placed powders was the best choice for improving the wear properties of the TiC coatings.
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Using Ni60 alloy, C, TiN and Mo mixed powders as the precursor materials, in situ synthesized Ti(C,N) particles reinforcing Ni-based composite coatings are produced on Ti6Al4V alloys by laser cladding. Phase constituents, microstructures and wear properties of the composite coatings with 0 wt % Mo, 4 wt % Mo and 8 wt % Mo additions are studied comparatively. Results indicate that Ti(C,N) is formed by the in situ metallurgical reaction, the (Ti,Mo)(C,N) rim phase surrounding the Ti(C,N) ceramic particle is synthesized with the addition of Mo, and the increase of Mo content is beneficial to improve the wear properties of the cladding coatings. Because of the effect of Mo, the grains are remarkably refined and a unique core-rim structure that is uniformly dispersed in the matrix appears; meanwhile, the composite coatings with Mo addition exhibit high hardness and excellent wear resistance due to the comprehensive action of dispersion strengthening, fine grain strengthening and solid solution strengthening.