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1.
Nature ; 632(8026): 782-787, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39143208

RESUMO

Hot-carrier transistors are a class of devices that leverage the excess kinetic energy of carriers. Unlike regular transistors, which rely on steady-state carrier transport, hot-carrier transistors modulate carriers to high-energy states, resulting in enhanced device speed and functionality. These characteristics are essential for applications that demand rapid switching and high-frequency operations, such as advanced telecommunications and cutting-edge computing technologies1-5. However, the traditional mechanisms of hot-carrier generation are either carrier injection6-11 or acceleration12,13, which limit device performance in terms of power consumption and negative differential resistance14-17. Mixed-dimensional devices, which combine bulk and low-dimensional materials, can offer different mechanisms for hot-carrier generation by leveraging the diverse potential barriers formed by energy-band combinations18-21. Here we report a hot-emitter transistor based on double mixed-dimensional graphene/germanium Schottky junctions that uses stimulated emission of heated carriers to achieve a subthreshold swing lower than 1 millivolt per decade beyond the Boltzmann limit and a negative differential resistance with a peak-to-valley current ratio greater than 100 at room temperature. Multi-valued logic with a high inverter gain and reconfigurable logic states are further demonstrated. This work reports a multifunctional hot-emitter transistor with significant potential for low-power and negative-differential-resistance applications, marking a promising advancement for the post-Moore era.

2.
J Hum Genet ; 69(5): 197-203, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38374166

RESUMO

CAPZA2 encodes the α2 subunit of CAPZA, which is vital for actin polymerization and depolymerization in humans. However, understanding of diseases associated with CAPZA2 remains limited. To date, only three cases have been documented with neurodevelopmental abnormalities such as delayed motor development, speech delay, intellectual disability, hypotonia, and a history of seizures. In this study, we document a patient who exhibited seizures, mild intellectual disability, and impaired motor development yet did not demonstrate speech delay or hypotonia. The patient also suffered from recurrent instances of respiratory infections, gastrointestinal and allergic diseases. A novel de novo splicing variant c.219+1 G > A was detected in the CAPZA2 gene through whole-exome sequencing. This variant led to exon 4 skipping in mRNA splicing, confirmed by RT-PCR and Sanger sequencing. To our knowledge, this is the third study on human CAPZA2 defects, documenting the fourth unambiguously diagnosed case. Furthermore, this splicing mutation type is reported here for the first time. Our research offers additional support for the existence of a CAPZA2-related non-syndromic neurodevelopmental disorder. Our findings augment our understanding of the phenotypic range associated with CAPZA2 deficiency and enrich the knowledge of the mutational spectrum of the CAPZA2 gene.


Assuntos
Proteína de Capeamento de Actina CapZ , Deficiências do Desenvolvimento , Epilepsia , Heterozigoto , Hipotonia Muscular , Mutação , Pré-Escolar , Feminino , Humanos , Masculino , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Epilepsia/genética , Sequenciamento do Exoma , Deficiência Intelectual/genética , Deficiência Intelectual/patologia , Hipotonia Muscular/genética , Hipotonia Muscular/patologia , Fenótipo , Splicing de RNA/genética , Proteína de Capeamento de Actina CapZ/genética
3.
J Nat Prod ; 87(4): 893-905, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38417166

RESUMO

The bridged polycyclic sesquiterpenoids derived from sativene, isosativene, and longifolene have unique structures, and many chemical synthesis approaches with at least 10 steps have been reported. However, their biosynthetic pathway remains undescribed. A minimal biosynthetic gene cluster (BGC), named bip, encoding a sesquiterpene cyclase (BipA) and a cytochrome P450 (BipB) is characterized to produce such complex sesquiterpenoids with multiple carbon skeletons based on enzymatic assays, heterologous expression, and precursor experiments. BipA is demonstrated as a versatile cyclase with (-)-sativene as the dominant product and (-)-isosativene and (-)-longifolene as minor ones. BipB is capable of hydroxylating different enantiomeric sesquiterpenes, such as (-)-longifolene and (+)-longifolene, at C-15 and C-14 in turn. The C-15- or both C-15- and C-14-hydroxylated products are then further oxidized by unclustered oxidases, resulting in a structurally diverse array of sesquiterpenoids. Bioinformatic analysis reveals the BipB homologues as a discrete clade of fungal sesquiterpene P450s. These findings elucidate the concise and divergent biosynthesis of such intricate bridged polycyclic sesquiterpenoids, offer valuable biocatalysts for biotransformation, and highlight the distinct biosynthetic strategy employed by nature compared to chemical synthesis.


Assuntos
Sistema Enzimático do Citocromo P-450 , Família Multigênica , Estrutura Molecular , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sesquiterpenos/metabolismo , Sesquiterpenos/química , Vias Biossintéticas/genética , Sesquiterpenos Policíclicos/química , Sesquiterpenos Policíclicos/metabolismo , Estereoisomerismo
4.
BMC Pediatr ; 24(1): 44, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218765

RESUMO

BACKGROUND: High mobility group box-1 (HMGB1) is an endogenous danger signal that mediates activation of the innate immune response including NLR pyrin domain containing 3 (NLRP3) inflammasome activation and proinflammatory cytokine release. Although HMGB1 and NLRP3 have been implicated in the pathophysiology of seizures, the correlation between HMGB1 and NLRP3 expression has not been determined in children with febrile seizures (FS). To explore the relationship between extra-cellular HMGB1 and NLRP3 in children with FS, we analyzed serum HMGB1, NLRP3, caspase-1, and proinflammatory cytokines in patients with FS. METHODS: Thirty children with FS and thirty age-matched febrile controls were included in this study. Blood was obtained from the children with FS within 1 h of the time of the seizure; subsequently, the serum contents of HMGB1, NLRP3, caspase-1, interleukin (IL)-1ß, interleukin (IL)-6, and tumour necrosis factor-α (TNF-α) were determined by enzyme-linked immunosorbent assay. The Mann‒Whitney U test was used to compare serum cytokine levels between FS patients and controls. Spearman's rank correlation coefficient was calculated to detect significant correlations between cytokine levels. RESULTS: Serum levels of HMGB1, NLRP3, caspase-1, IL-1ß, IL-6, and TNF-α were significantly higher in FS patients than in febrile controls (p < 0.05). Serum levels of HMGB1 were significantly correlated with levels of NLRP3 and caspase-1 (both, p < 0.05). Serum levels of caspase-1 were significantly correlated with levels of IL-1ß (p < 0.05). Serum levels of IL-1ß were significantly correlated with levels of IL-6 and TNF-α (p < 0.05). CONCLUSIONS: HMGB1 is up-regulated in the peripheral serum of FS patients, which may be responsible, at least in part, for the increased expression of NLRP3 and Caspase-1. Increased expression of caspase-1 was significantly associated with elevated serum levels of IL-1ß. Given that activated Caspase-1 directly regulates the expression of mature IL-1ß and positively correlates with activation of the NLRP3 inflammasome, our data suggest that increased levels of peripheral HMGB1 possibly mediate IL-1ß secretion through the activation of the NLRP3 inflammasome in children with FS. Thus, both HMGB1 and NLRP3 might be potential targets for preventing or limiting FS.


Assuntos
Proteína HMGB1 , Convulsões Febris , Criança , Humanos , Estudos de Casos e Controles , Caspases , Citocinas , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6 , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fator de Necrose Tumoral alfa
5.
Zhongguo Zhong Yao Za Zhi ; 49(2): 509-517, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403326

RESUMO

This study investigated the absorption profile of Wuwei Qingzhuo San in different intestinal segments and the absorption characteristics of its alkaloids(piperine, piperanine, piperlonguminine, and dihydropiperlonguminine). The everted gut sac model was established, and the chemical components of Wuwei Qingzhuo San in different intestinal segments were detected by UPLC-Q-TOF-MS. The content of piperine, piperanine, piperlonguminine, and dihydropiperlonguminine in intestinal absorption fluid was determined by UPLC-Q-TRAP-MS and the absorption parameters were calculated. The absorption characteristics in different intestinal segments at different time were analyzed. As a result, 27, 27, 8, and 6 absorbent components from Wuwei Qingzhuo San were detected in the intestinal cyst fluid of jejunum, ileum, duodenum, and colon by UPLC-Q-TOF-MS technology, respectively. It was also found that piperine, piperanine, piperlonguminine, and dihydropiperlonguminine from Wuwei Qingzhuo San showed linear absorption in various intestinal segments, with r values exceeding 0.9. In terms of absorption content, the components were ranked as piperine>piperanine>dihydropiperlonguminine>piperlonguminine in various intestinal segments, but the absorption rate and mechanism of each component varied. The results demonstrate that the absorption of the components of Wuwei Qingzhuo San in different intestinal segments is selective and is not a simple semi-permeable membrane permeation process.


Assuntos
Alcaloides , Piperidinas , Alcamidas Poli-Insaturadas , Benzodioxóis , Absorção Intestinal
6.
Pak J Pharm Sci ; 37(2): 327-336, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38767100

RESUMO

Pancreatic cancer (PC) is heterogeneous cancer having a high death rate and poor prognosis. The perioperative variables, such as anesthetics, may affect the cancer progression. Ciprofol is an intravenous anesthetic widely used recently. We aimed to explore the influence of ciprofol on PC and investigate its possible pathway. The proliferation, migration and invasion roles and apoptosis of ciprofol in human PC cells were examined using methylthiazolyldiphenyl-tetrazolium bromide, trans well and flow cytometery analysis. Then the putative targeted genes were examined using RNA-sequencing (RNA-seq) analysis. When differentially expressed genes (DEGs) were found, a protein-protein interaction network and pathway analyses were made. Moreover, MMP1 gene expression was confirmed in PC cells using quantitative real-time PCR. PANC-1 cells of PC were significantly suppressed with ciprofol in a dose-dependent and time-dependent way, and 20µg/mL ciprofol significantly suppressed tumor cell aggressiveness. Additionally, the RNA-seq analysis demonstrated that ciprofol controls the expression of 929 DEGs. 5 of 20 hub genes with increased connection were selected. Survival analysis demonstrated that MMP1 may be involved in the carcinogenesis and establishment of PC, reflecting the possible roles associated with ciprofol. Moreover, one target miRNA (hsa-miR-330-5p) of MMP1 was identified.


Assuntos
Movimento Celular , Proliferação de Células , Metaloproteinase 1 da Matriz , Invasividade Neoplásica , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Mapas de Interação de Proteínas
7.
Nat Chem Biol ; 17(5): 585-592, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33707784

RESUMO

YcaO enzymes catalyze several post-translational modifications on peptide substrates, including thioamidation, which substitutes an amide oxygen with sulfur. Most predicted thioamide-forming YcaO enzymes are encoded adjacent to TfuA, which when present, is required for thioamidation. While activation of the peptide amide backbone is well established for YcaO enzymes, the function of TfuA has remained enigmatic. Here we characterize the TfuA protein involved in methyl-coenzyme M reductase thioamidation and demonstrate that TfuA catalyzes the hydrolysis of thiocarboxylated ThiS (ThiS-COSH), a proteinaceous sulfur donor, and enhances the affinity of YcaO toward the thioamidation substrate. We also report a crystal structure of a TfuA, which displays a new protein fold. Our structural and mutational analyses of TfuA have uncovered conserved binding interfaces with YcaO and ThiS in addition to revealing a hydrolase-like active site featuring a Ser-Lys catalytic pair.


Assuntos
Proteínas Arqueais/química , Euryarchaeota/enzimologia , Methanobacteriaceae/enzimologia , Methanocaldococcus/enzimologia , Oxirredutases/química , Tioamidas/química , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Sítios de Ligação , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Euryarchaeota/genética , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Histidina/química , Histidina/genética , Histidina/metabolismo , Cinética , Lectina de Ligação a Manose/química , Lectina de Ligação a Manose/genética , Lectina de Ligação a Manose/metabolismo , Methanobacteriaceae/genética , Methanocaldococcus/genética , Modelos Moleculares , Mutação , Oligopeptídeos/química , Oligopeptídeos/genética , Oligopeptídeos/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Peptídeos/química , Peptídeos/genética , Peptídeos/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Especificidade por Substrato , Tioamidas/metabolismo
8.
PLoS Biol ; 18(2): e3000507, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32092071

RESUMO

The enzyme methyl-coenzyme M reductase (MCR) plays an important role in mediating global levels of methane by catalyzing a reversible reaction that leads to the production or consumption of this potent greenhouse gas in methanogenic and methanotrophic archaea. In methanogenic archaea, the alpha subunit of MCR (McrA) typically contains four to six posttranslationally modified amino acids near the active site. Recent studies have identified enzymes performing two of these modifications (thioglycine and 5-[S]-methylarginine), yet little is known about the formation and function of the remaining posttranslationally modified residues. Here, we provide in vivo evidence that a dedicated S-adenosylmethionine-dependent methyltransferase encoded by a gene we designated methylcysteine modification (mcmA) is responsible for formation of S-methylcysteine in Methanosarcina acetivorans McrA. Phenotypic analysis of mutants incapable of cysteine methylation suggests that the S-methylcysteine residue might play a role in adaption to mesophilic conditions. To examine the interactions between the S-methylcysteine residue and the previously characterized thioglycine, 5-(S)-methylarginine modifications, we generated M. acetivorans mutants lacking the three known modification genes in all possible combinations. Phenotypic analyses revealed complex, physiologically relevant interactions between the modified residues, which alter the thermal stability of MCR in a combinatorial fashion that is not readily predictable from the phenotypes of single mutants. High-resolution crystal structures of inactive MCR lacking the modified amino acids were indistinguishable from the fully modified enzyme, suggesting that interactions between the posttranslationally modified residues do not exert a major influence on the static structure of the enzyme but rather serve to fine-tune the activity and efficiency of MCR.


Assuntos
Aminoácidos/metabolismo , Methanosarcina/enzimologia , Oxirredutases/química , Oxirredutases/metabolismo , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Domínio Catalítico , Methanosarcina/genética , Methanosarcina/crescimento & desenvolvimento , Methanosarcina/metabolismo , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Modelos Moleculares , Mutação , Óperon , Oxirredutases/genética , Fenótipo , Processamento de Proteína Pós-Traducional/genética , Subunidades Proteicas , Temperatura
9.
J Nat Prod ; 86(10): 2333-2341, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37819880

RESUMO

Linaridins are a family of underexplored ribosomally synthesized and post-translationally modified peptides despite the prevalence of their biosynthetic gene clusters (BGCs) in microbial genomes, as shown by bioinformatic studies. Our genome mining efforts reveal that 96 putative oxidoreductase genes, namely, LinC, are encoded in linaridin BGCs. We heterologously expressed two such LinC-containing linaridin BGCs, yan and ydn, from Streptomyces yunnanensis and obtained three new linaridins, named yunnanaridins A-C (1-3). Their structures are characterized by Z-configurations of the dehydrobutyrines and the presence of a variety of epimerized amino acid residues. Yunnanaridin A (1) is the sixth member of the family of type-B linaridins, whereas yunnanaridins B (2) and C (3) represent the first examples of expressed type-C linaridins. Interestingly, heterologous expression of the same BGCs with LinC in-frame knockouts produced the same compounds. This work expands the structural diversity of linaridins and provides evidence for the notion that the widespread LinCs may not be involved in linaridin biosynthesis.


Assuntos
Biologia Computacional , Peptídeos , Peptídeos/química , Família Multigênica , Aminoácidos
10.
Ecotoxicol Environ Saf ; 266: 115594, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37856982

RESUMO

In the environmental safety area, the widespread use of the herbicide Paraquat (PQ) poses a great threat to hydrobionts and mammals. Due to the lack of specific antidote, it may lead to irreversible pulmonary fibrosis with a mortality rate of 60%. Therefore, it is necessary to develop an effective and specific PQ antidote. The g-C3N4 (HPCN) with excellent surface physicochemical properties was prepared by a two-step calcination method using urea and dicyandiamide as raw materials, showing a significant photocatalyst against environmental PQ pollution. The SEM results showed that HPCN possesses a porous layered structure. X-ray diffraction and infrared spectroscopy indicated that the conjugated aromatic rings were orderly stacked, forming a 2D layered structure of g-C3N4. The HPCN had a larger specific surface area (56.84 m2 g-1) and pore volume (0.2718 cm3 g-1), which enhanced its adsorption capacity and photocatalytic activity. HPCN exhibited an effective adsorption rate of 38.25% for PQ in water under light. Compared with the PQ group (54.8%), the cell viability of the HPCN group (91.4%) significantly increased by 36.6%, and the SEM observation revealed the restoration of normal cell morphology. The HPCN effectively reduced PQ content in zebrafish and mice in vivo, resulting in an approximately 70% increase in survival rate. The UV-Vis results indicated that the adsorption rate of HPCN for PQ in zebrafish was 43.5%. The enhanced catalytic performance of HPCN provides a promising solution for the detoxification of PQ and of other environmental pollutants.


Assuntos
Herbicidas , Fibrose Pulmonar , Animais , Camundongos , Paraquat/toxicidade , Peixe-Zebra , Antídotos , Herbicidas/toxicidade , Mamíferos
11.
Sensors (Basel) ; 23(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37687918

RESUMO

A tunnel health monitoring (THM) system ensures safe operations and effective maintenance. However, how to effectively process and denoise several data collected by THM remains to be addressed, as well as safety early warning problems. Thus, an integrated method for Savitzky-Golay smoothing (SGS) and Wavelet Transform Denoising (WTD) was used to smooth data and filter noise, and the coefficient of the non-uniform variation method was proposed for early warning. The THM data, including four types of sensors, were attempted using the proposed method. Firstly, missing values, outliers, and detrend in the data were processed, and then the data were smoothed by SGS. Furthermore, data denoising was carried out by selecting wavelet basis functions, decomposition scales, and reconstruction. Finally, the coefficient of non-uniform variation was employed to calculate the yellow and red thresholds. In data smoothing, it was found that the Signal Noise Ratio (SNR) and Root Mean Square Error (RMSE) of SGS smoothing were superior to those of the moving average smoothing and five-point cubic smoothing by approximately 10% and 30%, respectively. An interesting phenomenon was discovered: the maximum and minimum values of the denoising effects with different wavelet basis functions after selection differed significantly, with the SNR differing by 14%, the RMSE by 8%, and the r by up to 80%. It was found that the wavelet basis functions vary, while the decomposition scales are consistently set at three layers. SGS and WTD can effectively reduce the complexity of the data while preserving its key characteristics, which has a good denoising effect. The yellow and red warning thresholds are categorized into conventional and critical controls, respectively. This early warning method dramatically improves the efficiency of tunnel safety control.

12.
Int J Mol Sci ; 24(16)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37628967

RESUMO

Tumor-associated macrophages M2 (TAM2), which are highly prevalent infiltrating immune cells in the stroma of pancreatic cancer (PC), have been found to induce an immunosuppressive tumor microenvironment, thus enhancing tumor initiation and progression. However, the immune therapy response and prognostic significance of regulatory genes associated with TAM2 in PC are currently unknown. Based on TCGA transcriptomic data and single-cell sequencing data from the GEO database, we identified TAM2-driven genes using the WGCNA algorithm. Molecular subtypes based on TAM2-driven genes were clustered using the ConsensusClusterPlus algorithm. The study constructed a prognostic model based on TAM2-driven genes through Lasso-COX regression analysis. A total of 178 samples obtained by accessing TCGA were accurately categorized into two molecular subtypes, including the high-TAM2 infiltration (HMI) cluster and the low-TAM2 infiltration (LMI) cluster. The HMI cluster exhibits a poor prognosis, a malignant tumor phenotype, immune-suppressive immune cell infiltration, resistance to immunotherapy, and a high number of genetic mutations, while the LMI cluster is the opposite. The prognostic model composed of six hub genes from TAM2-driven genes exhibits a high degree of accuracy in predicting the prognosis of patients with PC and serves as an independent risk factor. The induction of TAM2 was employed as a means of verifying these six gene expressions, revealing the significant up-regulation of BCAT1, BST2, and MERTK in TAM2 cells. In summary, the immunophenotype and prognostic model based on TAM2-driven genes offers a foundation for the clinical management of PC. The core TAM2-driven genes, including BCAT1, BST2, and MERTK, are involved in regulating tumor progression and TAM2 polarization, which are potential targets for PC therapy.


Assuntos
Neoplasias Pancreáticas , Macrófagos Associados a Tumor , Humanos , c-Mer Tirosina Quinase , Sequência de Bases , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Análise de Sequência de RNA , Microambiente Tumoral/genética , Transaminases , Neoplasias Pancreáticas
13.
Int J Mol Sci ; 24(14)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37511038

RESUMO

Iron(Fe) is a trace metal element necessary for plant growth, but excess iron is harmful to plants. Natural resistance-associated macrophage proteins (NRAMPs) are important for divalent metal transport in plants. In this study, we isolated the MsNRAMP2 (MN_547960) gene from alfalfa, the perennial legume forage. The expression of MsNRAMP2 is specifically induced by iron excess. Overexpression of MsNRAMP2 conferred transgenic tobacco tolerance to iron excess, while it conferred yeast sensitivity to excess iron. Together with the MsNRAMP2 gene, MsMYB (MN_547959) expression is induced by excess iron. Y1H indicated that the MsMYB protein could bind to the "CTGTTG" cis element of the MsNRAMP2 promoter. The results indicated that MsNRAMP2 has a function in iron transport and its expression might be regulated by MsMYB. The excess iron tolerance ability enhancement of MsNRAMP2 may be involved in iron transport, sequestration, or redistribution.


Assuntos
Sobrecarga de Ferro , Nicotiana , Nicotiana/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Ferro/metabolismo , Medicago sativa/genética , Sobrecarga de Ferro/genética , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
14.
Entropy (Basel) ; 25(11)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37998191

RESUMO

In this paper, we employ PCA and t-SNE analyses to gain deeper insights into the behavior of entangled and non-entangled mixing operators within the Quantum Approximate Optimization Algorithm (QAOA) at various depths. We utilize a dataset containing optimized parameters generated for max-cut problems with cyclic and complete configurations. This dataset encompasses the resulting RZ, RX, and RY parameters for QAOA models at different depths (1L, 2L, and 3L) with or without an entanglement stage within the mixing operator. Our findings reveal distinct behaviors when processing the different parameters with PCA and t-SNE. Specifically, most of the entangled QAOA models demonstrate an enhanced capacity to preserve information in the mapping, along with a greater level of correlated information detectable by PCA and t-SNE. Analyzing the overall mapping results, a clear differentiation emerges between entangled and non-entangled models. This distinction is quantified numerically through explained variance in PCA and Kullback-Leibler divergence (post-optimization) in t-SNE. These disparities are also visually evident in the mapping data produced by both methods, with certain entangled QAOA models displaying clustering effects in both visualization techniques.

15.
Entropy (Basel) ; 25(2)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36832623

RESUMO

Understanding the evolutionary patterns of real-world complex systems such as human interactions, biological interactions, transport networks, and computer networks is important for our daily lives. Predicting future links among the nodes in these dynamic networks has many practical implications. This research aims to enhance our understanding of the evolution of networks by formulating and solving the link-prediction problem for temporal networks using graph representation learning as an advanced machine learning approach. Learning useful representations of nodes in these networks provides greater predictive power with less computational complexity and facilitates the use of machine learning methods. Considering that existing models fail to consider the temporal dimensions of the networks, this research proposes a novel temporal network-embedding algorithm for graph representation learning. This algorithm generates low-dimensional features from large, high-dimensional networks to predict temporal patterns in dynamic networks. The proposed algorithm includes a new dynamic node-embedding algorithm that exploits the evolving nature of the networks by considering a simple three-layer graph neural network at each time step and extracting node orientation by using Given's angle method. Our proposed temporal network-embedding algorithm, TempNodeEmb, is validated by comparing it to seven state-of-the-art benchmark network-embedding models. These models are applied to eight dynamic protein-protein interaction networks and three other real-world networks, including dynamic email networks, online college text message networks, and human real contact datasets. To improve our model, we have considered time encoding and proposed another extension to our model, TempNodeEmb++. The results show that our proposed models outperform the state-of-the-art models in most cases based on two evaluation metrics.

16.
Entropy (Basel) ; 25(7)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37509934

RESUMO

In this study, we investigate the position and momentum Shannon entropy, denoted as Sx and Sp, respectively, in the context of the fractional Schrödinger equation (FSE) for a hyperbolic double well potential (HDWP). We explore various values of the fractional derivative represented by k in our analysis. Our findings reveal intriguing behavior concerning the localization properties of the position entropy density, ρs(x), and the momentum entropy density, ρs(p), for low-lying states. Specifically, as the fractional derivative k decreases, ρs(x) becomes more localized, whereas ρs(p) becomes more delocalized. Moreover, we observe that as the derivative k decreases, the position entropy Sx decreases, while the momentum entropy Sp increases. In particular, the sum of these entropies consistently increases with decreasing fractional derivative k. It is noteworthy that, despite the increase in position Shannon entropy Sx and the decrease in momentum Shannon entropy Sp with an increase in the depth u of the HDWP, the Beckner-Bialynicki-Birula-Mycielski (BBM) inequality relation remains satisfied. Furthermore, we examine the Fisher entropy and its dependence on the depth u of the HDWP and the fractional derivative k. Our results indicate that the Fisher entropy increases as the depth u of the HDWP is increased and the fractional derivative k is decreased.

17.
Entropy (Basel) ; 25(9)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37761596

RESUMO

In this work, we investigate the Shannon entropy of four recently proposed hyperbolic potentials through studying position and momentum entropies. Our analysis reveals that the wave functions of the single-well potentials U0,3 exhibit greater localization compared to the double-well potentials U1,2. This difference in localization arises from the depths of the single- and double-well potentials. Specifically, we observe that the position entropy density shows higher localization for the single-well potentials, while their momentum probability density becomes more delocalized. Conversely, the double-well potentials demonstrate the opposite behavior, with position entropy density being less localized and momentum probability density showing increased localization. Notably, our study also involves examining the Bialynicki-Birula and Mycielski (BBM) inequality, where we find that the Shannon entropies still satisfy this inequality for varying depths u¯. An intriguing observation is that the sum of position and momentum entropies increases with the variable u¯ for potentials U1,2,3, while for U0, the sum decreases with u¯. Additionally, the sum of the cases U0 and U3 almost remains constant within the relative value 0.01 as u¯ increases. Our study provides valuable insights into the Shannon entropy behavior for these hyperbolic potentials, shedding light on their localization characteristics and their relation to the potential depths. Finally, we extend our analysis to the Fisher entropy F¯x and find that it increases with the depth u¯ of the potential wells but F¯p decreases with the depth.

18.
Chembiochem ; 23(24): e202200389, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36271784

RESUMO

Competitive proteome profiling is a powerful approach for the identification of targets of small molecules. This approach usually employs an inhibitor-derived probe or a cysteine-reactive probe such as an IA-alkyne in a comparison between inhibitor-treated and untreated samples, thus enabling distinction between genuine targets and nonspecific labeling. We have developed an active probe derived from an EGFR inhibitor, afatinib, and a cysteine reactive probe, an alkyne-containing α,ß-unsaturated amide, to compare their characterization of cellular targets. In both approaches, myosin heavy chain 9 (MYH9) was identified as an off-target. Subsequent functional validation experiments suggested that MYH9 might be involved in the function of afatinib.


Assuntos
Cisteína , Proteoma , Afatinib , Alcinos
19.
J Transl Med ; 20(1): 192, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35509084

RESUMO

Acute pancreatitis (AP) is a common clinical abdominal emergency, with a high and increasing incidence each year. Severe AP can easily cause systemic inflammatory response syndrome, multiple organ dysfunction and other complications, leading to higher hospitalization rates and mortality. Currently, there is no specific treatment for AP. Thus, we still need to understand the exact AP pathogenesis to effectively cure AP. With the rise of transcriptomics, RNA molecules, such as microRNAs (miRNAs) transcribed from nonprotein-coding regions of biological genomes, have been found to be of great significance in the regulation of gene expression and to be involved in the occurrence and development of many diseases. Increasing evidence has shown that miRNAs, as regulatory RNAs, can regulate pancreatic acinar necrosis and apoptosis and local and systemic inflammation and play an important role in the development and thus potentially the diagnosis and treatment of AP. Therefore, here, the current research on the relationship between miRNAs and AP is reviewed.


Assuntos
MicroRNAs , Pancreatite , Doença Aguda , Apoptose , Humanos , Inflamação , MicroRNAs/genética , Pancreatite/genética , Pancreatite/terapia
20.
Opt Lett ; 47(4): 917-920, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35167558

RESUMO

The angle-sensitive photonic bandgap (PBG) is one of the typical features of one-dimensional photonic crystals. Based on the phase-variation compensation effect between the dielectric and hyperbolic metamaterials (HMMs), angle-insensitive PBGs can be realized in photonic hypercrystals. However, since hypercrystals are usually constructed using metal components, these angle-insensitive PBGs are mostly limited to narrow bandwidths in visible range. Here, we replace metal with indium tin oxide (ITO) to construct HMMs in the near-infrared range. In these ITO-based HMMs, we experimentally demonstrate the negative refraction of light in transverse magnetic polarization. With this HMM component, we realize a photonic hypercrystal with an angle-insensitive PBG in the wavelength range of 1.15-2.02 µm. These ITO-based hypercrystals with large angle-insensitive PBGs can find applications in near-infrared reflectors or filters.

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