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1.
IEEE Trans Biomed Circuits Syst ; 18(2): 347-360, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37878421

RESUMO

The study of neuron interactions and hardware implementations are crucial research directions in neuroscience, particularly in developing large-scale biological neural networks. The FitzHugh-Nagumo (FHN) model is a popular neuron model with highly biological plausibility, but its complexity makes it difficult to apply at scale. This paper presents a cost-saving and improved precision approximation algorithm for the digital implementation of the FHN model. By converting the computational data into floating-point numbers, the original multiplication calculations are replaced by adding the floating-point exponent part and fitting the mantissa part with piecewise linear. In the hardware implementation, shifters and adders are used, greatly reducing resource overhead. Implementing FHN neurons by this approximation calculations on FPGA reduces the normalized root mean square error (RMSE) to 3.5% of the state-of-the-art (SOTA) while maintaining a performance overhead ratio improvement of 1.09 times. Compared to implementations based on approximate multipliers, the proposed method achieves a 20% reduction in error at the cost of a 2.8% increase in overhead.This model gained additional biological properties compared to LIF while reducing the deployment scale by only 9%. Furthermore, the hardware implementation of nine coupled circular networks with eight nodes and directional diffusion was carried out to demonstrate the algorithm's effectiveness on neural networks. The error decreased to 60% compared to the single neuron of the SOTA. This hardware-friendly algorithm allows for the low-cost implementation of high-precision hardware simulation, providing a novel perspective for studying large-scale, biologically plausible neural networks.


Assuntos
Modelos Neurológicos , Redes Neurais de Computação , Análise Custo-Benefício , Neurônios/fisiologia , Simulação por Computador
2.
Eur Rev Med Pharmacol Sci ; 25(10): 3640, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34109599

RESUMO

The article "MicroRNA-185 inhibits cell proliferation and epithelial-mesenchymal transition in hepatocellular carcinoma by targeting Six2, by S.-M. Zhu, C.-M. Chen, Z.-Y. Jiang, B. Yuan, M. Ji, F.-H. Wu, J. Jin, published in Eur Rev Med Pharmacol Sci 2016; 20 (9): 1712-1719-PMID: 27212161" has been withdrawn from the authors due to some technical reasons. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/10739.

3.
Eur Rev Med Pharmacol Sci ; 24(16): 8251-8262, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32894531

RESUMO

OBJECTIVE: Intervertebral disc (IVD) degeneration (IDD) is a well-known consequence of low back pain, as characterized by aberrant cell proliferation and apoptosis of nucleus pulposus (NP) cells. In the present study, we aimed to investigate the effect of lncRNA small nucleolar RNA host gene 6 (SNHG6) on deregulated functions of degenerative NP cells. MATERIALS AND METHODS: After the establishment of rat IDD models, the mRNA and protein levels of collagen-I (Col-I) and collagen II (Col-II), and mRNA level of SNHG6 were detected by using reverse transcription quantitative Real Time-PCR (RT-qPCR) and Western blot. We further investigated the role and molecular mechanisms of SNHG6 by overexpressing or silencing it in degenerative NP cells. Cell proliferation was measured by MTT assay and EdU staning, and apoptosis was measured by flow cytometry. The target of SNHG6 was identified by starBase and Dual-Luciferase reporter assay. RESULTS: Upregulation of SNHG6 was found in IDD NP cells than in normal cells, associated with higher level of Col-I and lower level of Col-II. Overexpression of SNHG6 inhibited cell proliferation and enhanced apoptosis, accompanied by increased expression of Bax, caspase-3, and p21, as well as decreased expression of Bcl-2, which was in reverse to the treatment of SNHG6 silencing. Moreover, miR-101-3p was indicated as a target of SNHG6, and inhibition of miR-101-3p reversed the effects on proliferation and apoptosis induced by SNHG6. CONCLUSIONS: SNHG6 suppressed cell proliferation and induced apoptosis by increasing expression of Bax, caspase-3, p21 and decreasing Bcl-2 through targeting miR-101-3p, which suggested that SNHG6 could be a potential target in the treatment of IDD.


Assuntos
Apoptose , MicroRNAs/metabolismo , Núcleo Pulposo/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Proliferação de Células , MicroRNAs/genética , Núcleo Pulposo/patologia , RNA Longo não Codificante/genética , Ratos , Ratos Wistar
4.
Eur Rev Med Pharmacol Sci ; 20(9): 1712-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27212161

RESUMO

OBJECTIVE: Epithelial-mesenchymal transition (EMT) plays an important role in the malignant transformation of cancer. MicroRNAs are a group of small non-coding RNA molecules that down-regulate the expression of genes involved in tumorigenesis. Although microRNA-185 (miR-185) participates in the pathogenesis of several types of cancer, its relationship with EMT in human hepatocellular carcinoma (HCC) has not been investigated. The present study aims to elucidate the regulatory effects of miR-185 on EMT in HCC cells. MATERIALS AND METHODS: MTT and an in vitro wound-healing assay were performed to determine cell growth and metastasis potential, respectively. Real-time PCR was used to measure the mRNA expression of miR-185 and Six2. In addition, protein expression levels of Six2 and EMT-related markers were determined by western blot. RESULTS: Our study showed that miR-185 was significantly down-regulated in HCC cells. Also, a luciferase reporter gene assay confirmed Six2 as a direct target of miR-185. Functional analyses indicated that miR-185 up-regulation remarkably suppressed cell growth and the metastatic potential of HCC cells. We also found that ectopic expression of miR-185 reversed EMT via the up-regulation of E-cadherin and down-regulation of vimentin in epithelial and mesenchymal HCC cells. CONCLUSIONS: miR-185 suppresses cell growth and EMT progression by targeting Six2, providing a novel target for the molecular treatment of liver malignancies.


Assuntos
Carcinoma Hepatocelular , Transição Epitelial-Mesenquimal/genética , MicroRNAs , Antígenos CD , Caderinas , Proliferação de Células/genética , Humanos , MicroRNAs/genética
5.
Genet Mol Res ; 14(4): 12692-8, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26505420

RESUMO

Stylosanthes guianensis is an elite and important forage legume species, which is extensively cultivated in tropical areas. Polyploid breeding via exposure to colchicine is a conventional and practical method to improve varieties of S. guianensis. Terminal buds of S. guianensis Reyan No.5 seedlings were treated with different concentrations of colchicine (0.00, 0.05, 0.10, 0.15, 0.20, and 0.25%) for 24, 48, and 72 h. Morphological and cytological variants were observed at a frequency of <96% among transplanted seedlings. The cytogenetic analysis of young leaf cells was conducted on all variants to identify their ploidy levels. The most efficient procedure for tetraploid production was the treatment of seedling apical buds with 20% colchicine for 48 h, with the tetraploid induction rate being 10%. This is a relatively simple and reliable method for the production of tetraploidy in S. guianensis.


Assuntos
Fabaceae/citologia , Fabaceae/metabolismo , Tetraploidia , Cromossomos de Plantas/efeitos dos fármacos , Cromossomos de Plantas/genética , Colchicina/farmacologia , Fabaceae/efeitos dos fármacos , Plântula/citologia , Plântula/efeitos dos fármacos , Plântula/metabolismo
6.
Curr Med Chem ; 22(19): 2392-403, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25989911

RESUMO

Alzheimer's disease (AD) is the most common type of dementia that leads to increasing death and mental disability among humans. Current therapy of AD mainly relies on the use of acetylcholinesterase inhibitors (AChEIs) or antagonists of N-methyl-D-aspartate receptors (NMDARs), which only relieve the symptoms of the disease but not halt its progression. Nevertheless, Traditional Chinese medicines (TCM) are highly prized as many bioactive components isolated from TCM are beneficial for treating AD. In this review, we summarize the latest information on TCM and the bioactive components according to their mechanistic role in alleviating AD. They act as modulators of α- and ß-secretases, and inhibitors of betaamyloid (Aß) aggregation. Some of them suppress Aß-induced neuronal cytotoxicity and inflammation. Hence, this work has demonstrated the feasibility of applying TCM in AD therapy and the possibility of screening of constituents in TCM in the near future.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Animais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Humanos
7.
Tree Physiol ; 29(6): 847-56, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19324693

RESUMO

Although bamboo is one of the most important woody crops in Asia, information on its genome is still very limited. To investigate the relationship among Poaceae members and to understand the mechanism of albino mutant generation in vitro, the complete chloroplast genome of two economically important bamboo species, Dendrocalamus latiflorus Munro and Bambusa oldhamii Munro, was determined employing a strategy that involved polymerase chain reaction (PCR) amplification using 443 novel primers designed to amplify the chloroplast genome of these two species. The lengths of the B. oldhamii and D. latiflorus chloroplast genomes are 139,350 and 139,365 bp, respectively. The organization structure and the gene order of these two bamboos are identical to other members of Poaceae. Highly conserved chloroplast genomes of Poaceae facilitated sequencing by the PCR method. Phylogenetic analysis using both chloroplast genomes confirmed the results obtained from studies on chromosome number and reproductive organ morphology. There are 23 gaps, insertions/deletions > 100 bp, in the chloroplast genomes of 10 genera of Poaceae compared in this study. The phylogenetic distribution of these gaps corresponds to their taxonomic placement. The sequences of these two chloroplast genomes provide useful information for studying bamboo evolution, ecology and biotechnology.


Assuntos
Bambusa/genética , Genoma de Cloroplastos/genética , Poaceae/genética , Bambusa/classificação , Filogenia , Poaceae/classificação , Reação em Cadeia da Polimerase
8.
J Protein Chem ; 15(8): 721-9, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9008295

RESUMO

For the 11 types of most frequently occurring supersecondary motifs, we used a new method--the vector projection method--to predict a protein's supersecondary structure. In a training set of peptides and a test set of peptides we obtained a satisfactory result, with a prediction accuracy of about 90%. The high prediction accuracy indicates that this method is reasonable for predicting the folding motifs of proteins. This work provides insight into the problem of predicting a protein's local structure accurately, and is of particular value in protein modeling, prediction, and molecule design.


Assuntos
Peptídeos/química , Estrutura Secundária de Proteína , Aminoácidos/química , Bases de Dados Factuais , Modelos Moleculares , Probabilidade , Conformação Proteica , Dobramento de Proteína , Software
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