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1.
Nat Commun ; 15(1): 4534, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806482

RESUMO

We report a breakthrough in the hardware implementation of energy-efficient all-spin synapse and neuron devices for highly scalable integrated neuromorphic circuits. Our work demonstrates the successful execution of all-spin synapse and activation function generator using domain wall-magnetic tunnel junctions. By harnessing the synergistic effects of spin-orbit torque and interfacial Dzyaloshinskii-Moriya interaction in selectively etched spin-orbit coupling layers, we achieve a programmable multi-state synaptic device with high reliability. Our first-principles calculations confirm that the reduced atomic distance between 5d and 3d atoms enhances Dzyaloshinskii-Moriya interaction, leading to stable domain wall pinning. Our experimental results, supported by visualizing energy landscapes and theoretical simulations, validate the proposed mechanism. Furthermore, we demonstrate a spin-neuron with a sigmoidal activation function, enabling high operation frequency up to 20 MHz and low energy consumption of 508 fJ/operation. A neuron circuit design with a compact sigmoidal cell area and low power consumption is also presented, along with corroborated experimental implementation. Our findings highlight the great potential of domain wall-magnetic tunnel junctions in the development of all-spin neuromorphic computing hardware, offering exciting possibilities for energy-efficient and scalable neural network architectures.

2.
Materials (Basel) ; 16(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36837206

RESUMO

The combined utilization of mineral accelerators and nano-seeding materials is a novel method to promote the early strength of cement-based materials. In this paper, the effects of nano-C-S-H seed (NCS) on the early compressive strength of the Portland cement (PC)- calcium sulfoaluminate cement (CSA) binder were investigated. The results showed that NCS and CSA synergistically contributed to the early strength of PC. In detail, a 326.3% increase in the 10 h compressive strength of PC paste was obtained through the addition of NCS (2 wt%) and CSA (5%) in common. This was higher than the sum of the increases observed with the single additions of CSA (157.9%) or NCS (87.6%), with the same above dosage, in PC. Meanwhile, the early strength enhancement effects of NCS and CSA, when used together in PC, lasted longer than the effects of either used alone. Moreover, the synergetic effect mechanism was analyzed by isothermal calorimeter, QXRD, TGA, MIP, and SEM techniques. The calorimetry, XRD, and TGA results demonstrated that the synergistic mechanism was associated with the synergistic promotion effects of CSA and NCS on the hydrates. The fast hydration of CSA produced large amounts of ettringite and also consumed partial free water to promote the performance of the seeding effect of NCS which, simultaneously, further accelerated the precipitation of C-S-H gel and CH. The high alkie environment was also beneficial for the continuous generation of ettringite. In addition, the results of MIP and SEM measurements showed that the micro-filling effect of NCS significantly optimized the pore structure of a PC-CSA blend-hardened paste. Thus, the synergistic strength enhancement effects of CSA and NCS on PC were attributed to the matching of the promotion of hydration generation and the optimization of pore structures in hardening cement paste. The results of this article provide a new approach to achieving the rapid development of the early strength of cementitious materials, with potential applications in precast concrete and low-temperature construction.

3.
Nat Commun ; 14(1): 1068, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36828856

RESUMO

Neuromorphic computing using nonvolatile memories is expected to tackle the memory wall and energy efficiency bottleneck in the von Neumann system and to mitigate the stagnation of Moore's law. However, an ideal artificial neuron possessing bio-inspired behaviors as exemplified by the requisite leaky-integrate-fire and self-reset (LIFT) functionalities within a single device is still lacking. Here, we report a new type of spiking neuron with LIFT characteristics by manipulating the magnetic domain wall motion in a synthetic antiferromagnetic (SAF) heterostructure. We validate the mechanism of Joule heating modulated competition between the Ruderman-Kittel-Kasuya-Yosida interaction and the built-in field in the SAF device, enabling it with a firing rate up to 17 MHz and energy consumption of 486 fJ/spike. A spiking neuron circuit is implemented with a latency of 170 ps and power consumption of 90.99 µW. Moreover, the winner-takes-all is executed with a current ratio >104 between activated and inhibited neurons. We further establish a two-layer spiking neural network based on the developed spintronic LIFT neurons. The architecture achieves 88.5% accuracy on the handwritten digit database benchmark. Our studies corroborate the circuit compatibility of the spintronic neurons and their great potential in the field of intelligent devices and neuromorphic computing.


Assuntos
Redes Neurais de Computação , Neurônios , Neurônios/fisiologia , Magnetismo
4.
BMC Med Genomics ; 15(1): 222, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36284275

RESUMO

INTRODUCTION AND OBJECTIVES: hepatocellular carcinoma (HCC) is the major form of liver cancer with a poor prognosis. Amino acid metabolism has been found to alter in cancers and contributes to malignant progression. However, the asparagine metabolism status and relevant mechanism in HCC were barely understood. METHODS: By conducting consensus clustering and the least absolute shrinkage and selection operator regression of HCC samples from three cohorts, we classified the HCC patients into two subtypes based on asparagine metabolism level. The Gene Ontology, Kyoto Encyclopedia of Genes and Genomes analyses and Gene Set Enrichment Analysis of the differentially expressed genes between two subgroups were conducted. Immune cell infiltration was evaluated using CIBERSORT algorithm. The prognostic values of genes were analyzed by univariate and multivariate cox regression, ROC curve and Kaplan-Meier survival estimate analyses. Cell types of sing-cell RNA sequencing (scRNA-seq) data were clustered utilizing UMAP method. RESULTS: HCC patients with higher asparagine metabolism level have worse prognoses. Moreover, we found the distinct energy metabolism patterns, DNA damage response (DDR) pathway activating levels, drug sensitivities to DDR inhibitors, immune cell compositions in the tumor microenvironment and responses to immune therapy between two subgroups. Further, we identified a potential target gene, glutamic-oxaloacetic transaminase 2 (GOT2). GOT2 downregulation was associated with worse HCC prognosis and increased infiltration of T regulatory cells (Tregs). ScRNA-seq revealed the GOT2 downregulation in cancer stem cells compared with HCC cells. CONCLUSIONS: Taken together, HCC subtype which is more reliant on asparagine and glutamine metabolism has a worse prognosis, and a core gene of asparagine metabolism GOT2 is a potential prognostic marker and therapeutic target of HCC. Our study promotes the precision therapy of HCC and may improve patient outcomes.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Asparagina/genética , Glutamina/genética , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica/métodos , Prognóstico , Aspartato Aminotransferases , Microambiente Tumoral
5.
Invest New Drugs ; 38(2): 229-245, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-30976957

RESUMO

The pharmacokinetic (PK) and potential effects of Emodin on liver cancer were systematically evaluated in this study. Both the intragastric administration (i.g.) and hypodermic injection (i.h.) of Emodin exhibited a strong absorption (absorption rate < 1 h) and elimination capacity (t1/2 ≈ 2 h). The tissue distribution of Emodin after i.h. was rapid and wide. The stability of Emodin in three species of liver microsomes wasrat >human> beagle dog. These PK data provided the basis for the subsequent animal experiments. In liver cancer patient tissues, the expression of vascular endothelial growth factor (VEGF)-induced signaling pathways, including phosphorylated VEGF receptor 2 (VEGFR2), AKT, and ERK1/2,were simultaneously elevated, but miR-34a expression was reduced and negatively correlated with SMAD2 and SMAD4. Emodin inhibited the expression of SMAD2/4 in HepG2 cells by inducing the miR-34a level. Subsequently, BALB/c nude mice received a daily subcutaneous injection of HepG2 cells with or without Emodin treatment (1 mg/kg or 10 mg/kg), and Emodin inhibited tumorigenesis and reduced the mortality rate in a dose-dependent manner. In vivo experiments showed that cell proliferation, migration, and invasion were promoted by VEGF or miR-34a signal treatment but were inhibited when combined with Emodin treatment. All these results demonstrated that Emodin inhibited tumorigenesis in liver cancer by simultaneously inhibiting the VEGFR2-AKT-ERK1/2signaling pathway and promoting a miR-34a-mediated signaling pathway.


Assuntos
Antineoplásicos/uso terapêutico , Emodina/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , MicroRNAs/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Proteínas Sanguíneas/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cães , Emodina/sangue , Emodina/farmacocinética , Emodina/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos
6.
Curr Cancer Drug Targets ; 20(1): 59-66, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31512996

RESUMO

BACKGROUND: Forkhead box C1 (FOXC1) is an important cancer-associated gene in tumor. PPAR-γ and C/EBPα are both transcriptional regulators involved in tumor development. OBJECTIVE: We aimed to clarify the function of PPAR-γ, C/EBPα in hepatocellular carcinoma (HCC) and the relationship of PPAR-γ, C/EBPα and FOXC1 in HCC. METHODS: Western blotting, immunofluorescent staining, and immunohistochemistry were used to evaluate protein expression. qRT-PCR was used to assess mRNA expression. Co-IP was performed to detect the protein interaction. And ChIP and fluorescent reporter detection were used to determine the binding between protein and FOXC1 promoter. RESULTS: C/EBPα could bind to FOXC1 promoter and PPAR-γ could strengthen C/EBPα's function. Expressions of C/EBPα and PPAR-γ were both negatively related to FOXC1 in human HCC tissue. Confocal displayed that C/EBPα was co-located with FOXC1 in HepG2 cells. C/EBPα could bind to FOXC1 promoter by ChIP. Luciferase activity detection exhibited that C/EBPα could inhibit FOXC1 promoter activity, especially FOXC1 promoter from -600 to -300 was the critical binding site. Only PPAR-γ could not influence luciferase activity but strengthen inhibited effect of C/EBPα. Further, the Co-IP displayed that PPAR-γ could bind to C/EBPα. When C/EBPα and PPAR-γ were both high expressed, cell proliferation, migration, invasion, and colony information were inhibited enormously. C/EBPα plasmid combined with or without PPAR-γ agonist MDG548 treatment exhibited a strong tumor inhibition and FOXC1 suppression in mice. CONCLUSION: Our data establish C/EBPα targeting FOXC1 as a potential determinant in the HCC, which supplies a new pathway to treat HCC. However, PPAR-γ has no effect on FOXC1 expression.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT/fisiologia , Carcinoma Hepatocelular/patologia , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , PPAR gama/fisiologia , Animais , Movimento Celular , Proliferação de Células , Fatores de Transcrição Forkhead/fisiologia , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Regiões Promotoras Genéticas
7.
Mol Med Rep ; 17(4): 5328-5335, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29393466

RESUMO

Intrahepatic cholangiocarcinoma (IHCC) is an aggressive cancer with a poor survival rate and is the second most common type of primary cancer of the hepatobiliary system. At present, the molecular mechanisms of IHCC initiation and progression remain unclear. Recent evidence has indicated that long non­coding RNAs (lncRNAs) serve a crucial role in cancer development; however, the functional role of lncRNAs in IHCC has not been investigated in detail. In the present study, a marked overexpression of lncRNA colon cancer­associated transcript 2 (CCAT2) was observed in IHCC cell lines and clinical specimens. Statistical analysis of IHCC clinicopathological characteristics and CCAT2 expression data revealed that high CCAT2 expression levels correlated with microvascular invasion, differentiation grade, tumor (T), lymph node (N), metastasis (M) and overall TNM stages of IHCC (P<0.05). Kaplan­Meier analysis demonstrated that CCAT2 upregulation was associated with poor overall survival and progression­free survival in IHCC. Furthermore, high CCAT2 expression was identified as an independent risk factor of IHCC poor prognosis in both univariate and multivariate Cox regression analyses. The role of CCAT2 in promoting IHCC cell proliferation, motility and invasion was further confirmed with in vitro assays. Therefore, CCAT2 may promote IHCC progression and metastasis, and may be a promising prognostic biomarker and therapeutic target in IHCC.


Assuntos
Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/mortalidade , Colangiocarcinoma/genética , Colangiocarcinoma/mortalidade , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Adulto , Idoso , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Proliferação de Células , Colangiocarcinoma/patologia , Progressão da Doença , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Curva ROC
8.
EBioMedicine ; 2(12): 2024-36, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26844283

RESUMO

BACKGROUND: Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease that causes a deficit of pancreatic islet ß cells. The complexities of overcoming autoimmunity in T1D have contributed to the challenges the research community faces when devising successful treatments with conventional immune therapies. Overcoming autoimmune T cell memory represents one of the key hurdles. METHODS: In this open-label, phase 1/phase 2 study, Caucasian T1D patients (N = 15) received two treatments with the Stem Cell Educator (SCE) therapy, an approach that uses human multipotent cord blood-derived multipotent stem cells (CB-SCs). SCE therapy involves a closed-loop system that briefly treats the patient's lymphocytes with CB-SCs in vitro and returns the "educated" lymphocytes (but not the CB-SCs) into the patient's blood circulation. This study is registered with ClinicalTrials.gov, NCT01350219. FINDINGS: Clinical data demonstrated that SCE therapy was well tolerated in all subjects. The percentage of naïve CD4(+) T cells was significantly increased at 26 weeks and maintained through the final follow-up at 56 weeks. The percentage of CD4(+) central memory T cells (TCM) was markedly and constantly increased at 18 weeks. Both CD4(+) effector memory T cells (TEM) and CD8(+) TEM cells were considerably decreased at 18 weeks and 26 weeks respectively. Additional clinical data demonstrated the modulation of C-C chemokine receptor 7 (CCR7) expressions on naïve T, TCM, and TEM cells. Following two treatments with SCE therapy, islet ß-cell function was improved and maintained in individuals with residual ß-cell function, but not in those without residual ß-cell function. INTERPRETATION: Current clinical data demonstrated the safety and efficacy of SCE therapy in immune modulation. SCE therapy provides lasting reversal of autoimmune memory that could improve islet ß-cell function in Caucasian subjects. FUNDING: Obra Social "La Caixa", Instituto de Salud Carlos III, Red de Investigación Renal, European Union FEDER Funds, Principado de Asturias, FICYT, and Hackensack University Medical Center Foundation.


Assuntos
Autoimunidade , Memória Imunológica , Imunomodulação , Transplante de Células-Tronco , Células-Tronco/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Adulto , Peptídeo C/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/terapia , Feminino , Seguimentos , Expressão Gênica , Humanos , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Receptores CCR7/genética , Receptores CCR7/metabolismo , Resultado do Tratamento , Adulto Jovem
9.
Zhonghua Zhong Liu Za Zhi ; 33(5): 358-62, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21875465

RESUMO

OBJECTIVE: To investigate the expression of RKIP, p65 and pERK in hepatocellular carcinoma (HCC) and theIr correlation with invasion and metastasis of HCC. METHODS: Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression of RKIP mRNA. The expression levels of RKIP, p65 and pERK proteins in HCC tumor and peritumoral tissues were determined by immunohistochemistry and Western blot analysis. Statistical analysis was performed to determine the relationship between their expression and clinicopathological parameters. RESULTS: RKIP protein expression level (RKIP/actin) was 0.579 ± 0.380 in HCCs, 1.178 ± 0.659 in peritumoral tissues and 1.115 ± 0.442 in normal liver tissues. The pERK protein level was 1.023 ± 0.478, 0.605 ± 0.367 and 0.461 ± 0.293, p65 protein level was 0.83 ± 0.376, 0.63 ± 0.337 and 0.466 ± 0.345, respectively. Immunohistochemistry analysis showed that the RKIP positive rates in HCCs, peritumoral tissues and normal liver tissues, were 22.2%, 86.0%, and 93.8%, positive rates of p65 were 73.6%, 56.0% and 37.5%, positive rates of pERK were 65.3%, 38.0% and 31.3%, respectively. Statistical analysis revealed that there was a significant difference in RKIP protein expression levels (P < 0.05), but no significant difference in RKIP mRNA expression levels (P > 0.05) among HCC tumors, peritumoral tissues and normal liver tissues. The p65-positive and pERK-positive rates were higher in tumor tissues than that in peritumoral tissues and in normal liver tissues (P < 0.05), but RKIP-positive rates were lower in tumor tissues than that in paritumoral tissues and normal liver tissues (P < 0.05). RKIP protein expression levels were significantly lower in HCCs with intrahepatic or lymphatic metastasis than that in without. The RKIP positive rates in moderately and well differentiated HCCs were significantly higher than that in poorly differentiated HCCs. There was a relationship between RKIP and pERK expressions (P = 0.04), but RKIP expression was not correlated with p65 expression in HCCs (P = 0.143). CONCLUSIONS: Our findings indicate that the down-regulation of RKIP expression may serve as a predictive marker for HCC development, progression and metastasis, which may contribute to the elevated ERK activity. The inhibiting effect of RKIP on invasion and metastasis of liver cancer cells may be due to the down-regulation of pERK expression rather than p65 expression.


Assuntos
Carcinoma Hepatocelular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Hepáticas , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Adulto , Idoso , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteína de Ligação a Fosfatidiletanolamina/genética , Fosforilação , RNA Mensageiro/metabolismo , Fator de Transcrição RelA/metabolismo
10.
World J Gastroenterol ; 12(2): 280-6, 2006 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-16482630

RESUMO

AIM: To study the expression of vascular endothelial growth factor A (VEGF-A) and VEGF-C and to determine whether the presence of VEGF-A and VEGF-C was associated with the clinicopathologic characteristics of pancreatic cancer. METHODS: VEGF-A and VEGF-C mRNA transcripts were examined by Northern blot in 6 human pancreatic cancer cell lines and 8 normal pancreatic tissues and 8 pancreatic carcinoma specimens. The expression of VEGF-A and VEGF-C proteins was examined by Western blot in the tested cell lines and by immunohistochemical stain in 50 pancreatic carcinoma samples. RESULTS: VEGF-A and VEGF-C mRNA transcripts were present in all the 6 human pancreatic cancer cell lines. Immunoblotting revealed the presence of VEGF-A and VEGF-C proteins in all the cell lines. Northern blot analysis of total RNA revealed 3.0-fold and 3.6-fold increase in VEGF-A and VEGF-C mRNA transcript in the cancer samples, respectively. Immunohistochemical analysis confirmed the expression of VEGF-A and VEGF-C in cancer cells within the tumor mass. Immunohistochemical analysis of 50 pancreatic cancer tissue samples revealed the presence of VEGF-A and VEGF-C immunoreactivity in 50% and 80% of the cancer tissue samples, respectively. The presence of VEGF-A in these cells was associated with larger tumor size and enhanced local spread (c2 = 6.690, P = 0.035<0.05) but was not associated with decreased patient survival. However, the presence of VEGF-C in the cancer cells was associated with increased lymph node metastasis (c2 = 5.710, P = 0.017 < 0.05), but was not associated with decreased patient survival. There was no correlation between the expression of VEGF-A and VEGF-C in the same cancer cells. CONCLUSION: VEGF-A and VEGF-C are commonly overexpressed in human pancreatic cancer and may contribute to tumor growth and lymph node metastasis. There is no relationship between the expression of VEGF-A and VEGF-C in pancreatic cancer.


Assuntos
Neoplasias Pancreáticas/química , Fator A de Crescimento do Endotélio Vascular/análise , Fator C de Crescimento do Endotélio Vascular/análise , Adulto , Idoso , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Pâncreas/química , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , RNA Mensageiro/análise , Fator A de Crescimento do Endotélio Vascular/genética , Fator C de Crescimento do Endotélio Vascular/genética
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