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Partial discharge detection is considered a crucial technique for evaluating insulation performance and identifying defect types in cable terminals of high-speed electric multiple units (EMUs). In this study, terminal samples exhibiting four typical defects were prepared from high-speed EMUs. A cable discharge testing system, utilizing high-frequency current sensing, was developed to collect discharge signals, and datasets corresponding to these defects were established. This study proposes the use of the convolutional neural network (CNN) for the classification of discharge signals associated with specific defects, comparing this method with two existing neural network (NN)-based classification models that employ the back-propagation NN and the radial basis function NN, respectively. The comparative results demonstrate that the CNN-based model excels in accurately identifying signals from various defect types in the cable terminals of high-speed EMUs, surpassing the two existing NN-based classification models.
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Face morphing attacks have become increasingly complex, and existing methods exhibit certain limitations in capturing fine-grained texture and detail changes. To overcome these limitation, in this study, a detection method based on high-frequency features and progressive enhancement learning was proposed. Specifically, in this method, first, high-frequency information are extracted from the three color channels of the image to accurately capture the details and texture changes. Next, a progressive enhancement learning framework was designed to fuse high-frequency information with RGB information. This framework includes self-enhancement and interactive-enhancement modules that progressively enhance features to capture subtle morphing traces. Experiments conducted on the standard database and compared with nine classical technologies revealed that the proposed approach achieved excellent performance.
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Meteorological factors have been confirmed to affect the COVID-19 transmission, but current studied conclusions varied greatly. The underlying causes of the variance remain unclear. Here, we proposed two scientific questions: (1) whether meteorological factors have a consistent influence on virus transmission after combining all the data from the studies; (2) whether the impact of meteorological factors on the COVID-19 transmission can be influenced by season, geospatial scale and latitude. We employed a meta-analysis to address these two questions using results from 2813 published articles. Our results showed that, the influence of meteorological factors on the newly-confirmed COVID-19 cases varied greatly among existing studies, and no consistent conclusion can be drawn. After grouping outbreak time into cold and warm seasons, we found daily maximum and daily minimum temperatures have significant positive influences on the newly-confirmed COVID-19 cases in cold season, while significant negative influences in warm season. After dividing the scope of the outbreak into national and urban scales, relative humidity significantly inhibited the COVID-19 transmission at the national scale, but no effect on the urban scale. The negative impact of relative humidity, and the positive impacts of maximum temperatures and wind speed on the newly-confirmed COVID-19 cases increased with latitude. The relationship of maximum and minimum temperatures with the newly-confirmed COVID-19 cases were more susceptible to season, while relative humidity's relationship was more affected by latitude and geospatial scale. Our results suggested that relationship between meteorological factors and the COVID-19 transmission can be affected by season, geospatial scale and latitude. A rise in temperature would promote virus transmission in cold seasons. We suggested that the formulation and implementation of epidemic prevention and control should mainly refer to studies at the urban scale. The control measures should be developed according to local meteorological properties for individual city.
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COVID-19 , COVID-19/epidemiología , Humanos , Conceptos Meteorológicos , SARS-CoV-2 , Estaciones del Año , TemperaturaRESUMEN
Endoplasmic reticulum aminopeptidase 1 (ERAP1), a metallopeptidase belonging to the M1 peptidase family, plays an important role in antigen processing in vivo. Additionally, many diseases are caused by ERAP1 perturbation. Thus, an efficient method for monitoring its content is extremely important for disease diagnosis and treatment. However, few fluorescent probes have been reported for efficiently monitoring ERAP1 in living cells and tissues. In this work, a two-photon fluorescent probe (SNCL) containing 1,8-naphthalimide (two-photon fluorophore), l-leucine (trigger moiety), and a methyl sulfonamide moiety (endoplasmic reticulum-targeting group) for imaging ERAP1 activity in living cells is reported for the first time. The optimized probe exhibited high sensitivity toward ERAP1, with about a 95-fold fluorescence enhancement at 550 nm. Herein, we monitored ERAP1 with SNCL by introducing interferon-γ to induce ERAP1 activity in living cells. The content of ERAP1 was dependent on the redox state of the endoplasmic reticulum, which was demonstrated by using SNCL to monitor the enzymatic activity of ERAP1 under different redox conditions. Excitingly, SNCL was also successfully applied for monitoring ERAP1 in tumor tissue with an imaging depth of 50-120 µm. In conclusion, SNCL not only can be used for the sensitive detection of endogenous ERAP1 in living cells and tumor tissues but also can serve as a potentially useful tool to reveal ERAP1-related diseases.
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Aminopeptidasas/análisis , Retículo Endoplásmico/enzimología , Colorantes Fluorescentes/química , Antígenos de Histocompatibilidad Menor/análisis , Fotones , Aminopeptidasas/metabolismo , Animales , Colorantes Fluorescentes/síntesis química , Células HeLa , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Microscopía Fluorescente , Antígenos de Histocompatibilidad Menor/metabolismo , Estructura Molecular , Imagen Óptica , Oxidación-ReducciónRESUMEN
Vascular endothelial cell growth factor (VEGF)-C promotes tumorigenesis by allowing lymph node metastasis and lymphangiogenesis, among other actions. RNA interference (RNAi) is a novel technique for suppressing target gene expression and may increase the effectiveness of cancer treatments. The present study assessed the influence of VEGF-C RNAi on the apoptosis and proliferation of mouse breast cancer cells in vitro and in vivo. A total of three pairs of small interfering RNA (siRNA) targeting mouse VEGF-C were designed and synthesized prior to transfection into 4T1 cells via a liposomal approach. Reverse transcription polymerase chain reaction, western blot analysis, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Hoechst 33258 staining and flow cytometry were performed in vitro to analyze VEGF-C expression, cleaved caspase-3 protein expression and 4T1 cell proliferation and apoptosis. Experiments were also conducted in vivo on BALB/c mice with breast cancer. Tumor weight and volume were measured and the number of apoptotic cells in tumor tissues was assessed by a TUNEL assay. Immunohistochemical assays and an enzyme-linked immunosorbent assay were used to measure the expression of VEGF-C in tumor tissues. The results demonstrated that the three pairs of siRNA, particularly siV2, significantly reduced VEGF-C mRNA and protein levels in 4T1 cells. siV2 was deemed to be the most efficient siRNA and therefore was selected to be used in subsequent experiments. Furthermore, in vitro studies indicated that VEGF-C RNAi significantly decreased cell growth, induced apoptosis and upregulated the expression of cleaved caspase-3 protein. Tumor weight and volume in breast cancer in vivo models was reduced by the intratumoral injection of siV2. Antitumor efficacy was associated with decreased VEGF-C expression and increased induction of apoptosis. The present study therefore indicated that VEGF-C RNAi inhibited mouse breast cancer growth in vitro and in vivo and that it may be a novel targeted therapy for breast cancer.
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Metastasis constantly occurs in the majority of cases of primary breast cancer at late stage or following surgical treatment. Survivin, a member of the inhibitor of apoptosis protein family, has long been recognized as a promising anticancer target, but its antitumor effects remain largely unexplored. In order to elucidate the role of survivin in breast cancer metastasis, short interfering RNA (siRNA) was used in the present study to specifically downregulate survivin expression in the murine breast cancer cell line 4T1. The results demonstrated that blocking the expression of survivin by siRNA inhibited the proliferation, migration and invasion abilities of murine breast cancer cells in vitro. Vascular endothelial growth factor (VEGF)-C is a lymphatic endothelial cell-stimulating factor that may lead to the formation of lymphatic vessels in lymph nodes. In the present study, the inhibition of survivin by siRNA was able to reduce the overexpression of VEGF-C in 4T1 cells. Furthermore, intratumoral injections of the survivin-siRNA significantly inhibited the growth of orthotopically transplanted 4T1 tumors in vivo. In addition, the number of pulmonary metastases and the microlymphatic vessel density were significantly reduced in vivo, following transfection with survivin-siRNA. The results of the present study suggested that the Akt/hypoxia-inducible factor-1α signaling pathway participates in the survivin-mediated downregulation of VEGF-C expression observed in breast cancer cells treated with survivin-siRNA. Therefore, the use of siRNA specifically targeting survivin may be a potential anticancer method in the future.
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CD44 is a transmembrane receptor for hyaluronic acid. CD44 pre-mRNA contains 19 exons, 9 of which are alternatively spliced. Among the CD44 spliced variants, the v4-7 variant, one of the v6 exon-containing isoforms that contains variable exon 4, 5, 6 and 7, confers metastatic potential to non-metastatic cells. Splicing of CD44 and the function of CD44 isoforms are different in breast cancer cells. hnRNP A1 is a ubiquitously expressed protein with an inhibitory function in pre-mRNA splicing. We showed that CD44v6 isoform, which includes all of the v6-containing mRNA isoforms, had the highest expression level in non-metatatic breast cancer cells (MCF7) when compared to the level in metastatic breast cancer cells (MDA-MB-231) and normal breast cells (MCF10A). Furthermore we showed that hnRNP A1 knockdown regulated splicing of CD44 differently in breast cancer cells. We showed here that CD44 isoform expression is completely different in MDA-MB-231 cells than that in MCF7 and MCF10A cells, whereas MCF7 and MCF10A cells had a similar expression pattern of CD44 isoforms. RT-PCR analysis of CD44v6 showed that MCF7 and MCF10A cells predominantly expressed the c5v6v7v8v9v10c6 isoform. However, in addition to this isoform, MDA-MB-231 cells also expressed the c5v6v8v9v10c6 and c5v6c6 isoforms. We also found that knockdown of hnRNP A1 significantly reduced the expression of c5v6v7v8v9v10c6 and c5v6v8v9v10c6, and promoted the expression of c5v6c6. hnRNP A1 knockdown significantly induced cell death. In addition, hnRNP A1 knockdown induced a decrease in cell invasion in the MDA-MB-231 cells. Our results indicate that the knockdown of hnRNP A1 has a specific function on the splicing of CD44 in breast cancer cells.
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Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/biosíntesis , Receptores de Hialuranos/genética , Invasividad Neoplásica/genética , Empalme Alternativo , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Supervivencia Celular/genética , Femenino , Técnica del Anticuerpo Fluorescente , Regulación Neoplásica de la Expresión Génica/fisiología , Técnicas de Silenciamiento del Gen , Ribonucleoproteína Nuclear Heterogénea A1 , Humanos , Receptores de Hialuranos/biosíntesis , Immunoblotting , Invasividad Neoplásica/patología , Isoformas de Proteínas , ARN Interferente Pequeño , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , TransfecciónRESUMEN
Gastric carcinoma is the fourth most common cancer worldwide, with a high rate of death and low 5-year survival rate. However, the mechanism underling gastric cancer is still not fully understood. Here in the present study, we identify the RNA-binding protein PCBP2 as an oncogenic protein in human gastric carcinoma. Our results show that PCBP2 is up-regulated in human gastric cancer tissues compared to adjacent normal tissues, and that high level of PCBP2 predicts poor overall and disease-free survival. Knockdown of PCBP2 in gastric cancer cells inhibits cell proliferation and colony formation in vitro, whereas opposing results are obtained when PCBP2 is overexpressed. Our in vivo subcutaneous xenograft results also show that PCBP2 can critically regulate gastric cancer cell growth. In addition, we find that PCBP2-depletion induces apoptosis in gastric cancer cells via up-regulating expression of pro-apoptotic proteins and down-regulating anti-apoptotic proteins. Mechanically, we identify that miR-34a as a target of PCBP2, and that miR-34a is critically essential for the function of PCBP2. In summary, PCBP2 promotes gastric carcinoma development by regulating the level of miR-34a.
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MicroARNs/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Unión al ARN/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Animales , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Femenino , Técnicas de Silenciamiento del Gen , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/genética , Persona de Mediana Edad , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Proteínas de Unión al ARN/antagonistas & inhibidores , Proteínas de Unión al ARN/genética , Neoplasias Gástricas/genética , Ensayo de Tumor de Célula MadreRESUMEN
A number of JmjC domain-containing histone demethylases have been identified and biochemically characterized in mammalian. JMJD2A is a transcriptional cofactor and enzyme that catalyzes demethylation of histone H3 lysines 9 and 36. Here in this study, we aim to explore the role of JMJD2A in human gastric cancer. Quantitative real-time PCR, Western blot and immunohistochemistry analyses reveal higher expression of JMJD2A in clinical gastric cancer tissues than that in normal gastric mucosa. JMJD2A expression is associated with tumor stage and nodal status, and high level of JMJD2A predicts poor overall and disease-free survival. Univariate and multivariate survival analyses demonstrate that JMJD2A could serve as an independent prognostic factor. Furthermore, we show that inhibition the expression of JMJD2A attenuates the growth and transformation of three lines of gastric cancer cells. Mechanically, JMJD2A knockdown induces apoptosis of gastric cancer cells by up-regulating the expression of pro-apoptotic proteins and by down-regulating anti-apoptotic protein. Finally, we show that JMJD2A level is correlated with the level of the pro-apoptotic microRNA miR-34a in gastric cancer tissues and JMJD2A represses the expression of miR-34a by decreasing its promoter activity. Those findings demonstrate that JMJD2A regulates gastric cancer growth and serves as an independent prognostic factor, and implicate that JMJD2A may be a promising target for intervention.
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Biomarcadores de Tumor/análisis , Histona Demetilasas con Dominio de Jumonji/análisis , Neoplasias Gástricas/química , Anciano , Anciano de 80 o más Años , Animales , Proliferación Celular , China/epidemiología , Supervivencia sin Enfermedad , Femenino , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis Linfática , Masculino , Ratones , Persona de Mediana Edad , Estadificación de Neoplasias , Prevalencia , Pronóstico , Medición de Riesgo , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Tasa de Supervivencia , Carga Tumoral , Células Tumorales CultivadasRESUMEN
BACKGROUND: Vascular endothelial growth factor-C (VEGF-C), which contributes to lymphatic metastasis (LM) in malignant disease, is one of the most important factors involved in physical and pathological lymphangiogenesis. Some VEGF-C related factors such as sine oculis homeobox homolog (SIX) 1, contactin (CNTN) 1 and dual specificity phosphatase (DUSP) 6 have been extensively studied in malignancies, but their expression levels and associations have still to be elucidated in stomach cancer. METHODS: We detected their expression levels in 30 paired stomach cancer tissues using quantitative real-time reverse transcription-PCR (qRT-PCR). The expression and clinical significance of each factor was analyzed using Wilcoxon signed rank sum test. The correlation among all the factors was performed by Spearman rank correlation analysis. RESULTS: The results suggest that VEGF-C and CNTN1 are significantly correlated with tumor size, SIX1 with the age and CNTN1 also with the cTNM stage. There are significant correlations of expression levels among VEGF-C, SIX1, CNTN1 and DUSP6. CONCLUSIONS: There exists an important regulatory crosstalk involving SIX1, VEGF-C, CNTN1 and DUSP6 in stomach cancer.
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Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Factor C de Crecimiento Endotelial Vascular/genética , Adulto , Anciano , Contactina 1/genética , Fosfatasa 6 de Especificidad Dual/genética , Femenino , Proteínas de Homeodominio/genética , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Three novel polyoxometalates (POMs) containing [Ni6(µ3-OH)3](9-) and [P2W15O56](12-) units were first made, showing the first hexa-nuclearity transition-metal substituted POMs (TMSPs) based on monomeric lacunary Dawson fragments, which further indicates that the hydrothermal technique can offer an effective way for making new TMSPs through lacunary POM fragments incorporated with high-nuclear TM clusters.
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OBJECTIVE: To assess the association between 2 single nucleotide polymorphisms (SNPs) of ETS1 gene and susceptibility to systemic lupus erythematosus (SLE) in a northern Chinese Han population. METHODS: Two SNPs within the ETS1 gene mapped to 11q23 were selected based on HapMap data. Genotyping was conducted with Taqman method in 231 patients with SLE and 474 healthy controls from Qilu Hospital, Shandong and analyzed with PLINK1.07 software. Haplotypes were analyzed with SHEsis software. RESULTS: A statistically significant difference was detected in the distribution of rs1128334 and rs4937333 genotypes between the two groups (all P< 0.01). For rs1128334, the frequency of the minor allele was 0.291 and 0.428 in controls and cases, respectively. For rs4937333, the minor allele frequency was 0.381 and 0.476 in controls and cases respectively. An A-C haplotype was found to be strongly associated with increased risk for SLE, while another haplotype G-C may reduce this risk. CONCLUSION: Our study has suggested that rs1128334 and rs4937333 are strongly associated with the risk for SLE in northern Chinese Han population.