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Due to digital micromirrors device (DMD) digital lithography limited by non-integer pixel errors, the edge smoothness of the exposed image is low and the sawtooth defects are obvious. To improve the image edge smoothness, an optimized pixel overlay method was proposed, which called the DMD digital lithography based on dynamic blur effect matching pixel overlay technology. The core of this method is that motion blur effect is cleverly introduced in the process of pixel overlap to carry out the lithography optimization experiment. The simulation and experimental results showed that the sawtooth edge was reduced from 1.666â µm to 0.27â µm by adopting the 1/2 dynamic blur effect to match pixel displacement superposition, which is far less than half of the sawtooth edge before optimization. The results indicated that the proposed method can efficiently improve the edge smoothness of lithographic patterns. We believe that the proposed optimization method can provide great help for high fidelity and efficient DMD digital lithography microfabrication.
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Loss of expression or protein kinase B (Akt1)-mediated post-translational modification of the RNA binding protein Poly r(C) binding protein 1 (PCBP1) is closely related to metastatic advancement of breast cancer. However, the role of PCBP1 in tumorigenesis is not completely defined. Using a xenograft orthotopic model of breast tumorigenesis (4T1-Pcbp1-/-), we show here that PCBP1 knockdown-induced tumorigenesis is inhibited by activation of the WNT signaling via treating with the glycogen synthase kinase 3 beta inhibitor TWS119, but not the Akt2/Akt3 inhibitor GSK690693. Mass cytometry-based evaluation of the tumor microenvironment (TME) revealed significantly more regulatory T cells (Tregs) and significantly less cytotoxic T cells in 4T1-Pcbp1-/-mice treated with saline control in comparison to mice treated with TWS119. Infiltrating cytotoxic T cells were phenotypically and functionally exhausted. Treatment with TWS119 resulted in rescue of cytotoxic T cell function and inhibition of suppressor activity of Tregs. Using cytotoxic T cells isolated from healthy donors, we show that TWS119-induced WNT signaling-mediated inhibition of cytotoxic T cell expansion is reliant on expression of PCBP1. In conclusion, decreased PCBP1 expression favors breast tumorigenesis by potentiating skewing of tumor infiltrating T cells towards Tregs, thereby effectively suppressing anti-tumor immunity.
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Neoplasias da Mama , Via de Sinalização Wnt , Animais , Feminino , Humanos , Camundongos , Carcinogênese , Transformação Celular Neoplásica , Proteínas de Ligação a DNA , Proteínas de Ligação a RNA/genética , Microambiente TumoralRESUMO
BACKGROUND: Patients with triple-negative breast cancer (TNBC) are better responders to neoadjuvant chemotherapy; however, they are poor in the durability of response with decreased overall and progression-free survival. METHODS: Given that significant improvements have been reported with PD-L1-PD-1 blockade in different cancers, we evaluated the in vitro and in vivo effectiveness of Tomivosertib (eFT-508), an anthracycline, adriamycin, and MNK1/2 inhibitor, which has been previously shown to inhibit translation of PD-L1 in mice model of liver cancer, alone or in combination using BC cell lines and an orthotopic xenograft mice model using the TNBC cell line MDA-MB-231. RESULTS: Within the context of The Cancer Genome Atlas (TCGA) dataset, expression of CD274 mRNA, which encodes programmed death-ligand 1 (PD-L1), was found to be significantly overexpressed in TNBC patients compared to patients with HER2 + or luminal breast cancer (BC). Even within TNBC sub-types, CD274 expression was significantly higher in the immune modulatory subtype (TNBC-IM). BC cells exhibited high IC50 = 0.85 ± 0.07 nM with Adriamycin and significantly lower IC50 = 0.23 ± 0.04 nM with eFT-508 (P < 0.01). Combination treatment showed in vitro synergism on chemosensitivity. Combination therapy also exhibited a synergistic effect on inhibition of tumor growth and lung colonization in vivo. Mass cytometry-based evaluation of the tumor microenvironment revealed significant attenuation of both PD-L1 and PD-L2 following mono- or combination therapy with eFT-508. CONCLUSIONS: Treatment with eFT-508 restored effector and cytotoxic function of tumor-infiltrating CD8 + T cells in mice. The remarkable efficacy observed both in vitro and in vivo, and clinical synergism with adriamycin, highlights the potential of eFT-508 as an alternative, yet more efficacious, therapeutic option for patients with TNBC.
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Antígeno B7-H1 , Neoplasias de Mama Triplo Negativas , Animais , Antígeno B7-H1/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Humanos , Camundongos , Piridinas , Pirimidinas , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Microambiente TumoralRESUMO
OBJECTIVE: To investigate the impact of long noncodingRNA (lncRNA) colorectal neoplasia differentially expressed (CRNDE) on hepatocellular cancer (HCC) cell propagation, invasion, and migration by mediating miR-203/ BCAT1 axis. METHODS: Microarray analysis was based on 25 pairs of HCC cancerous tissues and adjacent tissues. The expression levels of CRNDE, miR-203, and BCAT1 in HCC tissues were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). The liver cell line L-02 and HCC cell lines HepG2 and Huh-7 were utilized to assess the regulatory eï¬ects of CRNDE and miR-203 on HCC progression in vitro. Western blot was used to qualify BCAT1 protein expression level. Cell proliferation and apoptosis were evaluated using CCK-8 and flow cytometry analysis, whereas cell invasion and migration assay were performed by the Transwell assay. The relationship among CRNDE, miR-203, and BCAT1 was validated by dual luciferase assay. Tumor Xenograft study was established to verify the pathological effect of CRNDE on HCC development in vivo. RESULTS: The expression levels of the CRNDE and BCAT1 were upregulated in HCC tissues and cells, whereas miR-203 was downregulated in HCC. Knockdown of CRNDE or miR-203 overexpression would inhibit HCC cell propagation and metastasis, and induced cell apoptosis. Moreover, miR-203 was negatively correlated with CRNDE, the same as miR-203 with BCAT1. Dual luciferase assay showed that miR-203 was an inhibitory target of CRNDE, and BCAT1 was directly targeted by miR-203 as well. CONCLUSION: LncRNA CRNDE could enhance HCC tumorgenesis by sponging miR-203 and mediating BCAT1. LncRNA CRNDE might facilitate HCC cell propagation, invasiveness, and migration through regulating miR-203/ BCAT1 axis.
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Carcinoma Hepatocelular/genética , Movimento Celular/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologiaRESUMO
OBJECTIVE: This study endeavored to explore the relationship between exosome-derived lncRNA Double Homeobox A Pseudogene 8 (DUXAP8) and Chondroitin Polymerizing Factor 2 (CHPF2), and their roles in the pathogenesis of intracranial aneurysm (IA). METHODS: The shared targeted molecules (DUXAP8 and CHPF2) were detected via GSE122897 and GSE75436 datasets. A total of 312 patients with IAs were incorporated into this study. Exosomes were isolated from serum samples, and their identity was confirmed using Western blotting for exosomal markers (CD9, CD63 and ALIX). Inflammatory responses in IA tissues were evaluated using Hematoxylin-Eosin staining. CHPF2 protein concentration and the expression levels of DUXAP8 and CHPF2 mRNA in exosomal samples were assessed using Immunochemistry (IHC), Western Blotting, and qRT-PCR, respectively. Cell-based assays involving Human Umbilical Vein Endothelial Cells (HuvECs), including transfection with exosomal DUXAP8, Western Blotting, qRT-PCR, and Cell Counting Kit-8, were conducted. Receiver Operating Characteristic (ROC) curves were derived using SPSS. RESULTS: DUXAP8 level affects the level of CHPF2. DUXAP8 expression within exosomes was associated with increased CD9, CD63, ALIX and CHPF2 levels during IA development and inflammatory stress. In HuvECs, transfection with exosomes carrying DUXAP8 siRNA resulted in reduced CHPF2 expression, whereas DUXAP8 mimic increased CHPF2 concentrations. The Area Under the ROC Curve (AUC) for exosomal DUXAP8 expression and CHPF2 levels, and aneurysm size was 0.768 (95% CI, 0.613 to 0.924), 0.937 (95% CI, 0.853 to 1.000), and 0.943 (95% CI, 0.860, 1.000), respectively. CONCLUSION: Exosome-derived DUXAP8 promotes IA progression by affecting CHPF2 expression.
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Exossomos , Aneurisma Intracraniano , N-Acetilgalactosaminiltransferases , RNA Longo não Codificante , Humanos , Exossomos/genética , Exossomos/metabolismo , Genes Homeobox , Células Endoteliais da Veia Umbilical Humana/metabolismo , Aneurisma Intracraniano/genética , Aneurisma Intracraniano/metabolismo , MicroRNAs/metabolismo , Pseudogenes , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , N-Acetilgalactosaminiltransferases/metabolismoRESUMO
Pressure-sensitive paints (PSP) enable non-intrusive visualization of surface pressure distribution on model surface which is important for aerodynamic studies. However, conventional PSP materials suffer from photobleaching and inadequate sensitivity. In this work, we rationally designed and synthesized novel dendritic oxygen probes (PT1 and PT2) by covalently grafting fluorinated dendrons onto platinum tetrakis(pentafluorophenyl)porphyrin (PT0) (a common oxygen probe). Subsequently, PT2 loaded nanofibers membranes from polycaprolactone (PCL) were fabricated by electrospinning. Fabricated membranes showed high oxygen sensitivity (I0/I100 = 35.3) with excellent flexibility, good reversibility, and outstanding photostability (merely 2.0% intensity loss after prolonged irradiation). The pressure sensitivity was found around 0.73 % per kilopascal. Furthermore, significant variation in emission intensity with respect to the variation in air pressure (1.3-101.32 kPa), facilitates the naked eye visualization of the pressure distribution on the membrane surface. Such excellent oxygen and pressure sensitivity and photostability might be due to high fluorine contents of complex dendritic structure of PT2. This flexible fluorine-functionalized dendritic oxygen probe puts forward a facile and effective strategy to develop advanced PSP materials enabling accurate pressure mapping for aerodynamic studies.
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Microgroove structures with helical pitches in a wavelength level are increasingly required in optical areas. However, conventional manufacturing techniques generate relatively high stresses during pressing, resulting in poor precision when forming microgrooves. This paper reports on the mechanism of the ultrasonic vibration-assisted microgroove forming of precise hot-pressed optical glass. A finite element (FE) thermocompression model of the viscoelastic material was developed and the entire forming process was numerically simulated using coupled thermal-structural analysis. The analysis of several process parameters was carried out using orthogonal experiments, from which the optimum combination of parameters was selected. The glass thermoforming process is also assisted by ultrasonic vibration. The thermal and mechanical effects of vibration improved material flow and optimized forming results. The average maximum stress in the glass during the forming process was only 3.04 × 10-3 Mpa, while the maximum stress in the hot-pressing stage without ultrasound was 1.648 Mpa. The stress results showed that the material-forming stress is significantly reduced.
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Numerous studies have shown that long noncoding RNAs (lncRNAs) play a critical role in the malignant progression of cancer. However, the potential involvement of lncRNAs in colon adenocarcinoma (COAD) remains unexplored. In this study, the expression of lncRNA SNHG7 in colon cancer tissues and its correlation with clinical characteristics were analyzed based on data from The Cancer Genome Atlas (TCGA) database. SNHG7 was found to be highly expressed in 17 types of cancer, including COAD. Next, TCGA data were further investigated to identify differentially expressed genes, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed. In addition, the relationship between SNHG7 expression and clinical features were analyzed. SNHG7 expression was found to be a potentially valuable indicator for COAD diagnosis and prognosis. Finally, gene set enrichment analysis showed that SNHG7 may affect lupus erythematosus and reactome cellular senescence, possibly influencing the prognosis of patients with COAD. Altogether, these results suggest that SNHG7 may be associated with the occurrence and development of COAD, having potential diagnostic and prognostic value.
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OBJECTIVE: Hepatic ischemia/reperfusion injury (IRI) is an unsettled and intractable conundrum in clinical treatment after liver transplantation and resection. Cellular communication network factor 1 (CCN1) is upregulated in liver IRI and may play a key role in this process. The objective of this study is to investigate the regulatory mechanism of CCN1 in liver IRI, which may provide new insight into liver IRI clinical treatment. METHODS: The hepatic ischemia/reperfusion model was established in male C57BL/6 mice by occlusion of vessels in the liver followed by reperfusion. The mice were transfected with two small interfering RNAs (siRNAs) against CCN1 for CCN1 knockdown. The hypoxia/reoxygenation (HR) model was established in vitro using mouse hepatic cells followed by transfection with a siRNA and treatment with an ERK activator TPA to confirm the effects of CCN1 on the MEK/ERK pathway in liver IRI. RESULTS: In hepatic IRI, CCN1 was upregulated and its knockdown reduced alanine aminotransferase and aspartate transaminase levels, myeloperoxidase activity, and the levels of IL-6 and TNF-α. CCN1 downregulation alleviated inflammatory cell infiltration and apoptosis in the liver. The expressions of cleaved caspase-9, cleaved caspase-3, Bax, and CHOP were decreased with an increased Bcl-2 level after CCN1 knockdown. The phosphorylation and activation of proteins in ER stress and MEK/ERK pathway were inhibited by CCN1 knockdown. In vitro, the levels of proinflammatory cytokines, apoptosis-inducing proteins, and proteins in ER stress and MEK/ERK pathway, which were decreased by CCN1 knockdown in HR, were restored by TPA, confirming that the activation of ERK aggravated cell apoptosis after reoxygenation. CONCLUSION: Overall, CCN1 knockdown may suppress the inflammation, apoptosis during hepatic IRI by reducing the MEK/ERK pathway activation, which may be a breakthrough point in clinical alleviation of hepatic IRI caused by liver transplantation and resection.
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Sistema de Sinalização das MAP Quinases , Traumatismo por Reperfusão , Animais , Apoptose , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Transdução de SinaisRESUMO
Following the publication of this article, the authors have realized that Table I contained an error: The number of patients who were alive in the Rab22a high expression group should have been written as 77 instead of 772.
A corrected version of the Table is shown on the next page (the corrected datum is highlighted in bold). The authors sincerely apologize for the error that was introduced during the preparation of this Table, and regret any inconvenience that this mistake has caused. [the original article was published in International Journal of Molecular Medicine 45: 1037-1046, 2020; DOI: 10.3892/ijmm.2020.4486].
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RATIONALE: Follicular dendritic cell sarcoma (FDCS) is a rare malignant tumor that originates from germinal center follicular dendritic cells, and can occur at both nodal and extranodal sites. There are very few described cases of FDCS arising in the chest wall. PATIENT CONCERNS: A 44-year-old male patient presented with a history of right chest wall pain for 5 months. DIAGNOSES: Positron emission tomography/computed tomography showed a significant increase in F-fluorodeoxyglucose uptake and multiple small axillary lymph nodes without hypermetabolic lesions. Immunohistochemistry results of a core-needle biopsy indicated FDCS, which was consistent with the postoperative pathological examination. INTERVENTIONS: The patient underwent tumor resection with lymphadenectomy of level I axillary nodes. No metastasis in the lymph nodes was observed in the postoperative pathological examination. The patient did not accept chemotherapy or radiotherapy. OUTCOMES: After 18 months, the patient remains in good condition with no evidence of disease recurrence. LESSONS: This report highlights a rare case of a FDCS arising in the chest wall. Accurate clinical diagnosis and staging of this rare malignant sarcoma is essential for the developmnt of effective treatment strategies. Preoperative F-fluorodeoxyglucose positron emission tomography/computed tomography scanning combined with core-needle biopsy could provide differentiation between benign and malignant tumors, as well as lymph node involvement and metastatic status.
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Sarcoma de Células Dendríticas Foliculares/diagnóstico , Neoplasias Torácicas/diagnóstico , Parede Torácica , Adulto , Biópsia com Agulha de Grande Calibre , Dor no Peito/etiologia , Sarcoma de Células Dendríticas Foliculares/patologia , Sarcoma de Células Dendríticas Foliculares/cirurgia , Fluordesoxiglucose F18 , Humanos , Imuno-Histoquímica , Excisão de Linfonodo , Linfonodos/patologia , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Torácicas/patologia , Neoplasias Torácicas/cirurgia , Parede Torácica/diagnóstico por imagem , Parede Torácica/patologia , Parede Torácica/cirurgiaRESUMO
BACKGROUND: Wntless (Wls) is an essential protein that is necessary for the secretion of Wnt proteins. While numerous researches have demonstrated that aberrations in Wnt/ß-catenin expression lead to tumorigenesis and progression in many cancer types, the effects of Wls in breast cancer (BC) are less studied. METHODS: The mRNA and protein expression of Wls in BC cell lines were detected by RT-qPCR and Western blot; the protein expression of patient samples was detected by immunohistochemistry (IHC). The associations between Wls expression and clinicopathological factors as well as survival time, including overall survival (OS) and disease-free survival (DFS) were analyzed. Bioinformatics analysis was used to reveal the correlation between Wls genes and associated genes or pathways. RESULTS: Wls was overexpressed in BC cell lines and tissues. The expression level of Wls was significantly correlated with tumor size, estrogen receptor (ER), progesterone receptor (PR), Ki-67, molecular classification, and follow-up status. Spearman correlation analysis showed that Wls protein expression was negatively correlated with ER and PR, which was confirmed by bioinformatics analysis in mRNA level. However, there were positive relationships with MBNG (modified Black's nuclear grade), tumor size, Ki-67, molecular classification, follow-up, and vital status. Univariate and multivariate analysis showed that Wls was an independent prognostic factor for OS and DFS in BC patients. Moreover, Wls was a significant prognostic indicator of OS and DFS in a hormone receptor-positive (HR+) subgroup. GSEA showed that estrogen and androgen response, as well as epithelial-mesenchymal transition pathways, were up-regulated in the Wls high-expression group. CONCLUSION: Overexpression of Wls is a significant marker of worse prognosis in BC and might play a crucial role in the HR+ subgroup.
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Breast cancer (BC) is the most common female malignant tumor worldwide. The mechanism of tumorigenesis is still unclear. Rasrelated proteins in brain (Rab)22a belongs to the Ras superfamily, which may act as an oncogene and participate in carcinogenesis. The present study aims to identify whether Rab22a could be a novel biomarker of prognosis and determine the effects of Rab22a on BC cell progression. A total 258 BC and 56 paratumor or nontumor formalin fixed paraffin embedded tissues were stained through immunohistochemistry. The association between Rab22a expression and clinicopathological features, as well as overall survival status were analyzed. The expression level of Rab22a in breast cell lines were detected using reverse transcriptionquantitative PCR and western blotting. SKBR3 cells were infected with Rab22a short hairpin RNA lentivirus and the ability of cell proliferation, migration and invasion were measured. Gene Set Enrichment Analysis (GSEA) was employed to analyze the pathways involved in the Rab22a mRNA high level group. Rab22a was found to be overexpressed in BC tissues and upregulated in BC cells. High expression of Rab22a was related to a poor prognosis of patients with BC. Knockdown of Rab22a decreased the proliferation, migration and invasion ability of BC cells. GSEA indicated that certain pathways, including mammalian target of rapamycin complex 1 and protein secretion were upregulated, while pathways, such as hypoxia and KRas were downregulated in the Rab22a high level group. Rab22a is of prognostic value for BC and necessary for BC cell proliferation.
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Biomarcadores Tumorais/biossíntese , Neoplasias da Mama , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Proteínas rab de Ligação ao GTP/biossíntese , Adulto , Neoplasias da Mama/enzimologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Taxa de SobrevidaRESUMO
Nanoparticles are emerging as a new therapeutic modality due to their high stability, precise targeting, and high biocompatibility. Branched Au-Ag nanoparticles with polydopamine coating (Au-Ag@PDA) have strong near-infrared absorbance and no cytotoxicity but high photothermal conversion efficiency. However, the photothermal activity of Au-Ag@PDA in vivo and in vitro has not been reported yet, and the mechanism underlying the effects of photothermal nanomaterials is not clear. Therefore, in this study, the colorectal cancer cell line HCT-116 and nude mice xenografts were used to observe the photothermal effects of Au-Ag@PDA in vivo and in vitro. The results suggest that Au-Ag@PDA NPs significantly inhibited cell proliferation and induced apoptosis in colorectal cancer cells. Moreover, Au-Ag@PDA NP-mediated photothermal therapy inhibited the growth of tumors at doses of 50 and 100⯵g in vivo. The mechanisms through which Au-Ag@PDA NPs induced colorectal cancer cell death involved multiple pathways, including caspase-dependent and -independent apoptosis, mitochondrial damage, lysosomal membrane permeability, and autophagy. Thus, our findings suggest that Au-Ag@PDA NPs could be used as potential antitumor agents for photothermal ablation of colorectal cancer cells.
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Apoptose , Materiais Revestidos Biocompatíveis , Neoplasias Colorretais , Ouro , Hipertermia Induzida , Indóis , Nanopartículas Metálicas , Fototerapia , Polímeros , Prata , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacocinética , Materiais Revestidos Biocompatíveis/farmacologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Ouro/química , Ouro/farmacocinética , Ouro/farmacologia , Células HCT116 , Humanos , Indóis/química , Indóis/farmacocinética , Indóis/farmacologia , Masculino , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Polímeros/química , Polímeros/farmacocinética , Polímeros/farmacologia , Prata/química , Prata/farmacocinética , Prata/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Aggressive fibromatosis (AF) is a rare benign tumor, which occurs in the deep part of bone and muscle fibrous tissue. Clinical and pathological features can be challenging for definitive diagnosis. Here, we report a rare case of a large AF in the axilla. Interestingly, 18 F-fluorodeoxyglucose-positron emission tomography/computed tomography showed significant increase in standard uptake value. Surgical resection yielded a spindle cell tumor likely of fibromatosis origin which was positive for ß-catenin expression.
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CYP24A1 is overexpressed in colorectal cancer, and the reason for the dysregulation of CYP24A1 in colorectal cancer is still unknown. In the present study, experiments were designed to test whether CYP24A1 inhibition facilitated the antiproliferative effect of 1,25(OH)2D3. In addition, the role of methylation in the regulation of CYP24A1 expression in human colorectal cancer was investigated. The expression of CYP24A1 in SW480 and Caco2 colorectal cancer cells was inhibited by RNAi. CYP24A1 inhibition significantly increased the antiproliferative effects of 1,25(OH)2D3 in SW480 cells compared with 1,25(OH)2D3 treatment alone (16.78% ± 2.08% vs. 33.53% ± 2.47%, p < 0.05). In addition, CYP24A1 inhibition sensitized Caco2 cells to 1,25(OH)2D3. We also found that CYP24A1 inhibition induced ß-catenin to translocate from the nucleus to the plasma membrane in SW480 cells and enhanced the inhibitory effect of 1,25(OH)2D3 on C-myc. Furthermore, CYP24A1 mRNA expression in Caco2 cells was increased after demethylation treatment, and the expression of CYP24A1 induced by 1,25(OH)2D3 was significantly higher in cells treated with 5-aza-2'-deoxycytidine (DAC) than in an untreated group. In conclusion, inhibition of CYP24A1 expression enhances the antitumor effect of 1,25(OH)2D3 in colorectal cancer, and DNA methylation is involved in the regulation of CYP24A1 expression in a cell-dependent manner.
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Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/patologia , Metilação de DNA , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Vitamina D3 24-Hidroxilase/antagonistas & inibidores , Vitamina D3 24-Hidroxilase/genética , Vitamina D/análogos & derivados , Via de Sinalização Wnt , Antineoplásicos/farmacologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Humanos , RNA Interferente Pequeno/genética , Células Tumorais Cultivadas , Vitamina D/farmacologia , Vitamina D3 24-Hidroxilase/metabolismoRESUMO
The Anderson insulating states in Au nanoparticle assembly are identified and studied under the application of magnetic fields and gate voltages. When the inter-nanoparticle tunneling resistance is smaller than the quantum resistance, the system showing zero Mott gap can be insulating at very low temperature. In contrast to Mott insulators, Anderson insulators exhibit great negative magnetoresistance, inferring charge delocalization in a strong magnetic field. When probed by the electrodes spaced by ~200 nm, they also exhibit interesting gate-modulated current similar to the multi-dot single electron transistors. These results reveal the formation of charge puddles due to the interplay of disorder and quantum interference at low temperatures.
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Piezoresistive responses of nanoparticle thin-film strain sensors on flexible polyimide substrates were studied. Disordered interparticle tunneling introduces microscopic detour of charge conduction so as to reduce gauge factors. The disorder also results in large resistance change when current flows in the direction perpendicular to a unidirectional strain, reducing response anisotropy. For practical usages, stability and endurance of these strain sensors are confirmed with 7 × 10(4) bending cycles. Cracks form in devices under prolonged cyclic bending and slightly reduce gauge factor.
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How the interparticle tunnelling affects the charge conduction of self-assembled gold nanoparticles is studied by three means: tuning the tunnel barrier width by different molecule modification and by substrate bending, and tuning the barrier height by high-dose electron beam exposure. All approaches indicate that the metal-Mott insulator transition is governed predominantly by the interparticle coupling strength, which can be quantified by the room temperature sheet resistance. The Hubbard gap, following the prediction of quantum fluctuation theory, reduces to zero rapidly as the sheet resistance decreases to the quantum resistance. At very low temperature, the fate of devices near the Mott transition depends on the strength of disorder. The charge conduction is from nearest-neighbour hopping to co-tunnelling between nanoparticles in Mott insulators whereas it is from variable-range hopping through charge puddles in Anderson insulators. When the two-dimensional nanoparticle network is under a unidirectional strain, the interparticle coupling becomes anisotropic so the average sheet resistance is required to describe the charge conduction.