Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-38652766

RESUMO

Heterostructure catalysts are considered as promising candidates for promoting the oxygen evolution reaction (OER) process due to their strong electron coupling. However, the inevitable dissolution and detachment of the heterostructure catalysts are caused by the severe reconstruction, dramatically limiting their industrial application. Herein, the NiFe-layered double hydroxide (LDH) nanosheets attached on Mo-NiO microrods (Mo-NiO@NiFe LDH) by the preoxidation strategy of the core NiMoN layer are synthesized for ensuring the high catalytic performance and stability. Owing to the enhanced electron coupling and preoxidation process, the obtained Mo-NiO@NiFe LDH exhibits a superlow overpotential of 253 mV to achieve a practically relevant current density of 1000 mA cm-2 for OER with exceptional stability over 1200 h. Notably, the overall water splitting system based on Mo-NiO@NiFe LDH reveals remarkable stability, maintaining the catalytic activity at a current density of 1000 mA cm-2 for 140 h under industrial harsh conditions. Furthermore, the Mo-NiO@NiFe LDH demonstrates outstanding activity and long-term durability in a practical alkaline electrolyzer assembly with a porous membrane, even surpassing the performance of IrO2. This work provides a new sight for designing and synthesizing highly stable heterojunction electrocatalysts, further promoting and realizing the industrial electrocatalytic OER.

2.
Opt Lett ; 49(7): 1798-1801, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560866

RESUMO

Vectorial holography through a strongly scattering medium can facilitate various applications in optics and photonics. However, the realization of vectorial holography with arbitrary distribution of optical intensity is still limited because of experimental noise during the calibration of vectorial transmission matrix (TM) and reconstruction noise during the retrieval of input wavefront for a given holographic target. Herein, we propose and experimentally demonstrate the vectorial holography with arbitrary distribution of optical intensity over a multimode fiber (MMF) using the Tikhonov regularization. By optimizing the noise factor, the performance of vectorial holography over an MMF is improved compared with the conjugate transpose and inverse TM methods. Our results might shed new light on the optical communication and detection mediated by MMFs.

3.
Nat Commun ; 15(1): 1580, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383508

RESUMO

Orthogonality among channels is a canonical basis for optical multiplexing featured with division multiplexing, which substantially reduce the complexity of signal post-processing in demultiplexing. However, it inevitably imposes an upper limit of capacity for multiplexing. Herein, we report on non-orthogonal optical multiplexing over a multimode fiber (MMF) leveraged by a deep neural network, termed speckle light field retrieval network (SLRnet), where it can learn the complicated mapping relation between multiple non-orthogonal input light field encoded with information and their corresponding single intensity output. As a proof-of-principle experimental demonstration, it is shown that the SLRnet can effectively solve the ill-posed problem of non-orthogonal optical multiplexing over an MMF, where multiple non-orthogonal input signals mediated by the same polarization, wavelength and spatial position can be explicitly retrieved utilizing a single-shot speckle output with fidelity as high as ~ 98%. Our results resemble an important step for harnessing non-orthogonal channels for high capacity optical multiplexing.

4.
BMC Genomics ; 24(1): 347, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37353738

RESUMO

BACKGROUND: In large-scale high-throughput sequencing projects and biobank construction, sample tagging is essential to prevent sample mix-ups. Despite the availability of fingerprint panels for DNA data, little research has been conducted on sample tagging of whole genome bisulfite sequencing (WGBS) data. This study aims to construct a pipeline and identify applicable fingerprint panels to address this problem. RESULTS: Using autosome-wide A/T polymorphic single nucleotide variants (SNVs) obtained from whole genome sequencing (WGS) and WGBS of individuals from the Third China National Stroke Registry, we designed a fingerprint panel and constructed an optimized pipeline for tagging WGBS data. This pipeline used Bis-SNP to call genotypes from the WGBS data, and optimized genotype comparison by eliminating wildtype homozygous and missing genotypes, and retaining variants with identical genomic coordinates and reference/alternative alleles. WGS-based and WGBS-based genotypes called from identical or different samples were extensively compared using hap.py. In the first batch of 94 samples, the genotype consistency rates were between 71.01%-84.23% and 51.43%-60.50% for the matched and mismatched WGS and WGBS data using the autosome-wide A/T polymorphic SNV panel. This capability to tag WGBS data was validated among the second batch of 240 samples, with genotype consistency rates ranging from 70.61%-84.65% to 49.58%-61.42% for the matched and mismatched data, respectively. We also determined that the number of genetic variants required to correctly tag WGBS data was on the order of thousands through testing six fingerprint panels with different orders for the number of variants. Additionally, we affirmed this result with two self-designed panels of 1351 and 1278 SNVs, respectively. Furthermore, this study confirmed that using the number of genetic variants with identical coordinates and ref/alt alleles, or identical genotypes could not correctly tag WGBS data. CONCLUSION: This study proposed an optimized pipeline, applicable fingerprint panels, and a lower boundary for the number of fingerprint genetic variants needed for correct sample tagging of WGBS data, which are valuable for tagging WGBS data and integrating multi-omics data for biobanks.


Assuntos
Genoma , Sulfitos , Humanos , Sequenciamento Completo do Genoma , Genótipo , Metilação de DNA , DNA , Sequenciamento de Nucleotídeos em Larga Escala
5.
Opt Lett ; 47(13): 3359-3362, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35776624

RESUMO

Subwavelength all-dielectric resonators supporting Mie resonances are promising building blocks in nanophotonics. The coupling of dielectric resonators facilitates advanced shaping of Mie resonances. However, coupled dielectric resonators with anisotropic geometry can only be designed by time-consuming simulation utilizing parameter scanning, hampering their applications in nanophotonics. Herein, we propose and demonstrate that a combination of two fully connected networks can effectively design coupled dielectric resonators with targeted eigenfrequency and Q factor. Typical examples are given for validating the proposed network, where the normalized deviation rates of eigenfrequency and Q factor are 0.39% and 1.29%, respectively. The proposed neutral network might become a useful tool in designing coupled dielectric resonators and beyond.

6.
J Bone Miner Res ; 37(5): 885-895, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35279875

RESUMO

Osteosarcoma is characterized by diverse genetic mutations, including single-nucleotide variants (SNVs), which can complicate clinical outcomes of the treatment. This study identified key mutations or polymorphisms in genes that correlate with osteosarcoma prognoses. A total of 110 patients with osteosarcoma were assigned to "good" or "poor" cohorts depending on their 5-year disease-free survival (DFS) after surgery and chemotherapeutic treatment. We performed next-generation sequencing analysis of tumor tissues for prognosis-associated SNVs in 315 tumorigenesis-related genes, followed by modeling of clinical outcomes for these patients using random forest classification via a support vector machine (SVM). Data from the Chinese Millionome Database were used to compare SNV frequency in osteosarcoma patients and healthy people. SVM screening identified 17 nonsynonymous SNVs located in 15 genes, of which rs17224367 and rs3733406 (located in MSH2 and FAT1, respectively) were strongly correlated with osteosarcoma prognosis. These results were verified in a 26-patient validation cohort, confirming that these SNVs could be used to predict prognosis. These results demonstrated that two SNVs located in MSH2 and FAT1 are associated with prognosis of osteosarcoma patients. © 2022 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Neoplasias Ósseas , Caderinas , Proteína 2 Homóloga a MutS , Osteossarcoma , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , China , Humanos , Proteína 2 Homóloga a MutS/genética , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Prognóstico
7.
AMB Express ; 11(1): 32, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33630191

RESUMO

To investigate and compare the gut microbiota structures in complete intensive feeding pattern (CP) and extensive feeding pattern (EP) groups, a total of 20 pigs were divided into two groups and fed the same diet. The fecal microbial composition was profiled using 16S rRNA gene sequencing. Our results showed that seventeen predominant genera were present in each pig sample and constituted the phylogenetic core of the microbiota at the class level. The abundance of most of the core microbial flora were significantly higher in the CP group than in the EP group (P < 0.05), while the abundance of Gammaproteobacteria was significantly lower in the CP group than in the EP group (P < 0.05). The CP group had significantly greater community diversity, richness, and evenness than the EP group (P < 0.05). Functional prediction analysis indicated that intestinal microbial species potentially led to faster growth and an increased fat accumulation capacity in the CP group; however, disease resistance was weaker in the CP group than in the EP group. In conclusion, EP pigs have a wider range of activity and better animal welfare than CP pigs, which helps reduce the occurrence of diseases and neurological symptoms. To explore the effect of intestinal flora on disease resistance in pigs at the molecular level, Coprococcus, which is a key gut bacterium in the intestine, was selected for isolation and purification and cocultured with intestinal epithelial cells. qPCR was performed to determine the effect of Coprococcus on SLA-DRB gene expression in intestinal epithelial cells. The results showed that Coprococcus enhanced SLA-DRB gene expression in intestinal epithelial cells. The results provide useful reference data for further study on the relationship between intestinal flora and pig disease resistance.

8.
Oncol Lett ; 19(5): 3495-3505, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32269623

RESUMO

Lung cancer is the most common type of cancer and the leading cause of cancer-associated death worldwide. Malignant pleural effusion (MPE), which is observed in ~50% of advanced non-small cell lung cancer (NSCLC) cases, and most frequently in lung adenocarcinoma, is a common complication of stage III-IV NSCLC, and it can be used to predict a poor prognosis. In the present study, multiple oncogene mutations were detected, including 17 genes closely associated with initiation of advanced lung cancer, in 108 MPE samples using next generation sequencing (NGS). The NGS data of the present study had broader coverage, deeper sequencing depth and higher capture efficiency compared with NGS findings of previous studies on MPE. In the present study, using NGS, it was demonstrated that 93 patients (86%) harbored EGFR mutations and 62 patients possessed mutations in EGFR exons 18-21, which are targets of available treatment agents. EGFR L858R and exon 19 indel mutations were the most frequently observed alterations, with frequencies of 31 and 25%, respectively. In 1 patient, an EGFR amplification was identified and 6 patients possessed a T790M mutation. ALK + EML4 gene fusions were identified in 6 patients, a ROS1 + CD74 gene fusion was detected in 1 patient and 10 patients possessed a BIM (also known as BCL2L11) 2,903-bp intron deletion. In 4 patients, significant KRAS mutations (G12D, G12S, G13C and A146T) were observed, which are associated with resistance to afatinib, icotinib, erlotinib and gefitinib. There were 83 patients with ERBB2 mutations, but only two of these mutations were targets of available treatments. The results of the present study indicate that MPE is a reliable specimen for NGS based detection of somatic mutations.

9.
Genomics ; 112(1): 199-206, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30707936

RESUMO

Reproductive performance is a complex quantitative trait, that is determined by multiple genes, regulatory pathways and environmental factors. A list of major genes with large effect have been detected, although multiple QTLs are identified. To identify candidate genes for pig prolificacy, whole genome variants from five high- and five low-prolificacy Yorkshire sows were collected using whole-genome resequencing. A total of 13,955,609 SNPs and 2,666,366 indels were detected across the genome. Common differential SNPs and indels were identified between the two groups of sows. Genes encoding components of the TGF-beta signaling pathway were enriched with the variations, including BMP5, BMP6, BMP7, ACVR1, INHBA, ZFYVE9, TGFBR2, DCN, ID4, BAMBI, and ACVR2A. Several differential variants within these genes related to reproductive traits were identified to be associated with litter size. A comparison of selective regions and published QTL data suggests that NEDD9, SLC39A11, SNCA, and UNC5D are candidate genes for reproduction traits.


Assuntos
Reprodução/genética , Sus scrofa/genética , Animais , Mineração de Dados , Feminino , Fertilidade/genética , Genes , Mutação INDEL , Fenótipo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Sequenciamento Completo do Genoma
10.
Gene ; 688: 204-214, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30529098

RESUMO

Disease causes large economic losses to the pig industry worldwidely, immunity plays an important role in the process of resistance to disease. In the present study, to elucidate the molecular mechanisms underlying different levels of disease resistance, we obtained the miRNA and mRNA expression profiles from the spleens of three groups of sows, including 180-day-old Queshan Black (Q-F), 3-day-old Yorkshire (Y-N) and 180-day-old Yorkshire (Y-F) pigs. The results showed that 85 miRNAs and 5093 genes were differentially expressed in Y-F vs Y-N, and 20 miRNAs and 1283 genes were differentially expressed in Q-F vs Y-F. Gene ontology analysis of these differentially expressed genes revealed their critical roles in response to immune response-related signaling pathways. To investigate the molecular mechanisms underlying immune diversity based on differentially expressed miRNAs and genes, the regulatory network between the node miRNAs and genes were established using Cytoscape. The results showed that the identified candidate miRNAs and genes were associated with immune response, and also indicated their potential roles in disease resistance variance between different pig breeds and stages. From the above, this research detected the key factors that were involved in disease resistance, and provide useful information for disease resistance breeding.


Assuntos
MicroRNAs/genética , RNA Mensageiro/genética , Baço/metabolismo , Transcriptoma/genética , Animais , Cruzamento/métodos , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Redes Reguladoras de Genes/genética , Suínos
11.
Plant Cell ; 29(10): 2661-2675, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28874509

RESUMO

Maize (Zea mays) floury3 (fl3) is a classic semidominant negative mutant that exhibits severe defects in the endosperm but fl3 plants otherwise appear normal. We cloned the fl3 gene and determined that it encodes a PLATZ (plant AT-rich sequence and zinc binding) protein. The mutation in fl3 resulted in an Asn-to-His replacement in the conserved PLATZ domain, creating a dominant allele. Fl3 is specifically expressed in starchy endosperm cells and regulated by genomic imprinting, which leads to the suppressed expression of fl3 when transmitted through the male, perhaps as a consequence the semidominant behavior. Yeast two-hybrid screening and bimolecular luciferase complementation experiments revealed that FL3 interacts with the RNA polymerase III subunit 53 (RPC53) and transcription factor class C 1 (TFC1), two critical factors of the RNA polymerase III (RNAPIII) transcription complex. In the fl3 endosperm, the levels of many tRNAs and 5S rRNA that are transcribed by RNAPIII are significantly reduced, suggesting that the incorrectly folded fl3 protein may impair the function of RNAPIII. The transcriptome is dramatically altered in fl3 mutants, in which the downregulated genes are primarily enriched in pathways related to translation, ribosome, misfolded protein responses, and nutrient reservoir activity. Collectively, these changes may lead to defects in endosperm development and storage reserve filling in fl3 seeds.


Assuntos
Impressão Genômica/genética , Zea mays/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Ribossômico/genética , RNA Ribossômico 5S/genética , RNA de Transferência/genética
12.
Cell Biochem Funct ; 34(7): 491-496, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27650047

RESUMO

Dysregulation of microRNAs has been demonstrated to contribute to malignant progression of cancers, including hepatocellular carcinoma (HCC). MiR-24-3p was previously reported to be significantly upregulated in HCC. However, the potential role and mechanism of action of miR-24-3p in the initiation and progression of HCC remain largely unknown. Quantitative reverse transcription polymerase chain reaction demonstrated that miR-24-3p was significantly upregulated in HCC tumor tissues compared with nontumor tissues. The cell viability, colony formation assay, and tumorigenicity assays in nude mice showed that miR-24-3p could enhance HCC cell growth in vitro and in vivo. Metallothionein 1M was verified as an miR-24-3p target gene by using dual-luciferase reporter assays, quantitative reverse transcription polymerase chain reaction, and Western blotting, which was involved in miR-24-3p regulated HCC cell growth. These results indicated that miR-24-3p plays an important role in the initiation and progression of HCC by targeting metallothionein 1M, and the miR-24-3p/metallothionein 1M pathway may contribute to the development of novel therapeutic strategies for HCC in the future.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Metalotioneína/genética , MicroRNAs/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , Metalotioneína/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Regulação para Cima/genética
13.
ScientificWorldJournal ; 2013: 596724, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24363621

RESUMO

To improve the performance of distributed information retrieval in search engines, we propose a two-level cache structure based on the queries of the users' logs. We extract the highest rank queries of users from the static cache, in which the queries are the most popular. We adopt the dynamic cache as an auxiliary to optimize the distribution of the cache data. We propose a distribution strategy of the cache data. The experiments prove that the hit rate, the efficiency, and the time consumption of the two-level cache have advantages compared with other structures of cache.


Assuntos
Armazenamento e Recuperação da Informação/métodos , Ferramenta de Busca , Redes de Comunicação de Computadores/estatística & dados numéricos , Armazenamento e Recuperação da Informação/estatística & dados numéricos , Internet/estatística & dados numéricos , Ferramenta de Busca/estatística & dados numéricos
14.
ScientificWorldJournal ; 2013: 978548, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24174920

RESUMO

Aiming at the stalemate that precision, speed, robustness, and other parameters constrain each other in the parallel processed vision servo system, this paper proposed an adaptive load capacity balance strategy on the servo parameters optimization algorithm (ALBPO) to improve the computing precision and to achieve high detection ratio while not reducing the servo circle. We use load capacity functions (LC) to estimate the load for each processor and then make continuous self-adaptation towards a balanced status based on the fluctuated LC results; meanwhile, we pick up a proper set of target detection and location parameters according to the results of LC. Compared with current load balance algorithm, the algorithm proposed in this paper is proceeded under an unknown informed status about the maximum load and the current load of the processors, which means it has great extensibility. Simulation results showed that the ALBPO algorithm has great merits on load balance performance, realizing the optimization of QoS for each processor, fulfilling the balance requirements of servo circle, precision, and robustness of the parallel processed vision servo system.

15.
ScientificWorldJournal ; 2013: 827376, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24191145

RESUMO

It is of great significance to research the early warning system for large-scale network security incidents. It can improve the network system's emergency response capabilities, alleviate the cyber attacks' damage, and strengthen the system's counterattack ability. A comprehensive early warning system is presented in this paper, which combines active measurement and anomaly detection. The key visualization algorithm and technology of the system are mainly discussed. The large-scale network system's plane visualization is realized based on the divide and conquer thought. First, the topology of the large-scale network is divided into some small-scale networks by the MLkP/CR algorithm. Second, the sub graph plane visualization algorithm is applied to each small-scale network. Finally, the small-scale networks' topologies are combined into a topology based on the automatic distribution algorithm of force analysis. As the algorithm transforms the large-scale network topology plane visualization problem into a series of small-scale network topology plane visualization and distribution problems, it has higher parallelism and is able to handle the display of ultra-large-scale network topology.


Assuntos
Algoritmos , Redes de Comunicação de Computadores , Segurança Computacional , China , Modelos Teóricos
16.
J Integr Plant Biol ; 54(2): 87-98, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22353560

RESUMO

Gene expression in chloroplasts is regulated by many nuclear-encoded proteins. In this study, we isolated a rice (Oryza sativa subsp. japonica) mutant osotp51 with significant reduction in photosystem I (PSI). The osotp51 is extremely sensitive to light and accumulates a higher level of reactive oxygen species. Its leaves are almost albino when grown at 40 µmol photons/m(2) per s. However, grown at 4 µmol photons/m(2) per s, osotp51 has a similar phenotype to the wild-type. 77K chlorophyll fluorescence analysis showed a blue shift in the highest peak emission from PSI in osotp51. In addition, the level of PSI and PSII dimer is dramatically reduced in osotp51. OSOTP 51 encodes a pentatricopeptide repeats protein, homologous to organelle transcript processing 51 in Arabidopsis. Loss-of-function OSOTP51 affects intron splicing of a number of plastid genes, particularly the ycf3 coding a protein involved in the assembly of PSI complex. OSOTP51 is functionally conserved in higher plants. The mutation of osotp51 indirectly leads to a widespread change in the structure and functions of PSI, results in severe photoinhibition, and finally dies, even when grown under very low light intensity.


Assuntos
Luz , Mutação/genética , Oryza/genética , Oryza/efeitos da radiação , Complexo de Proteína do Fotossistema I/genética , Proteínas de Plantas/genética , Western Blotting , Clorofila/metabolismo , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Íntrons/genética , Nitroazul de Tetrazólio/metabolismo , Oryza/crescimento & desenvolvimento , Fenótipo , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Folhas de Planta/ultraestrutura , Proteínas de Plantas/metabolismo , Splicing de RNA/genética , Splicing de RNA/efeitos da radiação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Plântula/efeitos da radiação , Espectrometria de Fluorescência , Tilacoides/metabolismo , Tilacoides/efeitos da radiação , Tilacoides/ultraestrutura , Fatores de Tempo
17.
Oncol Rep ; 26(4): 877-85, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21687954

RESUMO

Non-small cell lung carcinoma (NSCLC) is a leading cause of cancer-related deaths. Aberrance of the two oncogenes MET and SOX2 are frequently encountered in NSCLC. Exons 18 through 21 of the EGFR gene were screened and MET and SOX2 immunostaining was conducted to analyze the immunohistological staining of MET and SOX2 and the EGFR mutation status. One hundred and fifty tissue samples were examined including 57 squamous cell carcinomas (SCCs), 80 adenocarcinomas (ADCs), 9 adenosquamous carcinomas (ADSCs) and 4 large cell carcinomas (LCCs). The 32 NSCLCs harboring an EGFR mutation included 28 ADCs, 3 SCCs and 1 ADSC. A higher level of SOX2 expression appeared in NSCLCs without the EGFR mutation compared to those with EGFR mutation (χ2=9.02, P=0.0027). Of the 28 ADCs, 24 (85.7%) with an EGFR mutation showed low level of SOX2 expression. ADCs with deletion in exon 19 overexpressed MET and showed low levels of SOX2. SOX2 expression was inversely correlated to the expression of MET in NSCLC and mainly present in non-mutated NSCLC (r=-0.42, P<0.0001). There was a tendency for SOX2 to be expressed in SCCs and particularly in the part of SCC among ADSCs, whereas MET was mainly expressed in the part of ADC among ADSCs and ADCs. High level of MET and SOX2 expression were respectively demonstrated in ADCs and SCCs; MET activation was accompanied with exon 19 deletion in ADCs. EGFR and MET coordinate to drive tumorigenesis. Detection of the activation of MET and EGFR may be used for targeted drug therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Mutação , Proteínas Proto-Oncogênicas c-met/genética , Fatores de Transcrição SOXB1/genética , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-met/biossíntese , Fatores de Transcrição SOXB1/biossíntese
18.
Int J Biochem Cell Biol ; 42(12): 2072-81, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20887798

RESUMO

Myostatin (Mstn) is a secreted growth factor predominately expressed in skeletal muscle that negatively regulates skeletal muscle mass. Recent studies have indicated that loss function of myostatin not only increases muscle mass but also improves insulin sensitivity in vivo. In the present report, we demonstrated that myostatin regulates glucose metabolism by promoting glucose consumption and glucose uptake, increasing glycolysis, and inhibiting glycogen synthesis in skeletal muscle cells. Microarray analysis revealed that myostatin upregulates several genes involved in regulating glucose metabolism such as Glut1, Glut4, Hk2, and IL-6. Further investigation of the molecular basis of these phenomena revealed that AMP-activated protein kinase (AMPK), a key component for maintaining energy homeostasis, was activated by myostatin for promotion of glycolysis. Taken together, these findings provide the first experimental evidence that myostatin regulates glucose metabolism through the AMPK signal pathway in muscle cells. Importantly, our findings highlight that continued investigation of the metabolic function of myostatin is necessary for a comprehensive understanding of its active role in the regulation of skeletal muscle energy metabolism.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Glucose/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Miostatina/farmacologia , Animais , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Glicogênio/biossíntese , Glicólise/efeitos dos fármacos , Células HeLa , Humanos , Insulina/metabolismo , Insulina/farmacologia , Camundongos , Camundongos Knockout , Músculo Esquelético/enzimologia , Ratos , Transdução de Sinais/efeitos dos fármacos
19.
Biochem Biophys Res Commun ; 388(1): 112-6, 2009 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-19646957

RESUMO

Myostatin is a strong inhibitor of muscle growth, and its expression is increased in several types of muscle atrophy. However, whether or not myostatin expression is altered in muscle atrophy associated with type 1 diabetes (T1D) remains uncertain. In this study, we provided experimental evidence to show that myostatin mRNA increased in the early stage of T1D but came back to control levels later on. This expression pattern was closely correlated with the loss of body weight and atrogin-1 expression. Furthermore, induction of myostatin expression could be attenuated by insulin in T1D mice. Taken together, our findings indicate that the upregulation of myostatin expression most likely contributes to the muscle atrophy process during insulin deficiency.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/farmacologia , Atrofia Muscular/genética , Miostatina/genética , Animais , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Musculares/genética , Músculo Esquelético , Atrofia Muscular/etiologia , Miostatina/fisiologia , Proteínas Ligases SKP Culina F-Box/genética , Estreptozocina , Regulação para Cima/efeitos dos fármacos , Redução de Peso/genética
20.
Cell Signal ; 20(8): 1452-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18472397

RESUMO

Myostatin is a negative regulator of skeletal muscle growth and affects numerous genes expression involved in cell proliferation, differentiation and metabolism. However, the molecular mechanisms underlying myostatin-regulated genes expression remain to be elucidated. In this study, we showed that myostatin blocked the recruitment of p300 to the cyclin D1 promoter, resulting in the silence of cyclin D1 expression. Our data further demonstrated that myostatin decreased the protein level of p300 by inducing p300 degradation via the ubiquitin-proteasome system. In addition, we provided experimental evidence to show that myostatin-induced p300 degradation was mediated by the phosphatidylinositol 3-kinase/PTEN/Akt signaling pathway and this could be antagonized by IGF-1 or insulin. Results presented in this study uncovered an epigenetic control of genes expression in response to myostatin.


Assuntos
Ciclina D1/genética , Inativação Gênica , Transdução de Sinais , Fator de Crescimento Transformador beta/farmacologia , Fatores de Transcrição de p300-CBP/metabolismo , Animais , Linhagem Celular , Insulina/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Mioblastos/efeitos dos fármacos , Mioblastos/enzimologia , Mioblastos/metabolismo , Miostatina , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Regiões Promotoras Genéticas , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/antagonistas & inibidores , Ubiquitina/metabolismo , Fatores de Transcrição de p300-CBP/análise , Fatores de Transcrição de p300-CBP/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA