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1.
Int J Mol Sci ; 24(12)2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37373039

RESUMEN

Autophagy plays important but complex roles in aging, affecting health and longevity. We found that, in the general population, the levels of ATG4B and ATG4D decreased during aging, yet they are upregulated in centenarians, suggesting that overexpression of ATG4 members could be positive for healthspan and lifespan. We therefore analyzed the effect of overexpressing Atg4b (a homolog of human ATG4D) in Drosophila, and found that, indeed, Atg4b overexpression increased resistance to oxidative stress, desiccation stress and fitness as measured by climbing ability. The overexpression induced since mid-life increased lifespan. Transcriptome analysis of Drosophila subjected to desiccation stress revealed that Atg4b overexpression increased stress response pathways. In addition, overexpression of ATG4B delayed cellular senescence, and improved cell proliferation. These results suggest that ATG4B have contributed to a slowdown in cellular senescence, and in Drosophila, Atg4b overexpression may have led to improved healthspan and lifespan by promoting a stronger stress response. Overall, our study suggests that ATG4D and ATG4B have the potential to become targets for health and lifespan interventions.


Asunto(s)
Drosophila melanogaster , Longevidad , Anciano de 80 o más Años , Animales , Humanos , Envejecimiento/metabolismo , Drosophila melanogaster/metabolismo , Estrés Oxidativo
2.
Phys Chem Chem Phys ; 24(3): 1237-1261, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-34935801

RESUMEN

The photocatalyst surface is central to photocatalytic reactions. However, it has been a challenge to explicitly understand both the surface configuration and the structure-dependent photocatalytic properties at the atomic level. First-principles density functional theory (DFT) calculations provide a versatile method that makes up for the lack of experimental surface studies. In DFT calculations, the initial surface model greatly affects the accuracy of the calculation results. Consequently, establishing a more realistic and more reliable material surface models is undoubtedly the first step and the most important link in theoretical calculations. The aim of this Perspective is to provide a general understanding of the methods for the surface modeling of photocatalytic materials in recent years. We begin with a discussion of the basic theories applied in photocatalytic surface research, followed by an explanation of the importance of surface modeling in photocatalysis. We then elaborate on the advantages and disadvantages of the basic surface model and briefly describe the latest surface modeling methods. Finally, we evaluate the rationality of current surface modeling methods. We summarize this Perspective by prospecting the developing directions of photocatalytic surface research in the future. It is believed that a reasonable surface model should be verified by both experimental characterization and theoretical computation with negative feedback.

3.
Int J Mol Sci ; 23(22)2022 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-36430913

RESUMEN

To identify new factors that promote longevity and healthy aging, we studied Drosophila CG13397, an ortholog of the human NAGLU gene, a lysosomal enzyme overexpressed in centenarians. We found that the overexpression of CG13397 (dNAGLU) ubiquitously, or tissue specifically, in the nervous system or fat body could extend fly life span. It also extended the life span of flies overexpressing human Aß42, in a Drosophila Alzheimer's disease (AD) model. To investigate whether dNAGLU could influence health span, we analyzed the effect of its overexpression on AD flies and found that it improved the climbing ability and stress resistance, including desiccation and hunger, suggesting that dNAGLU improved fly health span. We found that the deposition of Aß42 in the mushroom body, which is the fly central nervous system, was reduced, and the lysosomal activity in the intestine was increased in dNAGLU over-expressing flies. When NAGLU was overexpressed in human U251-APP cells, which expresses a mutant form of the Aß-precursor protein (APP), APP-p.M671L, these cells exhibited stronger lysosomal activity and and enhanced expression of lysosomal pathway genes. The concentration of Aß42 in the cell supernatant was reduced, and the growth arrest caused by APP expression was reversed, suggesting that NAGLU could play a wider role beyond its catalytic activity to enhance lysosomal activity. These results also suggest that NAGLU overexpression could be explored to promote healthy aging and to prevent the onset of neurodegenerative diseases, including AD.


Asunto(s)
Enfermedad de Alzheimer , Longevidad , Anciano de 80 o más Años , Animales , Humanos , Longevidad/genética , Drosophila/genética , Enfermedad de Alzheimer/genética , Ejercicio Físico , Lisosomas
4.
Genome Res ; 28(11): 1601-1610, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30352807

RESUMEN

Centenarians (CENs) are excellent subjects to study the mechanisms of human longevity and healthy aging. Here, we analyzed the transcriptomes of 76 centenarians, 54 centenarian-children, and 41 spouses of centenarian-children by RNA sequencing and found that, among the significantly differentially expressed genes (SDEGs) exhibited by CENs, the autophagy-lysosomal pathway is significantly up-regulated. Overexpression of several genes from this pathway, CTSB, ATP6V0C, ATG4D, and WIPI1, could promote autophagy and delay senescence in cultured IMR-90 cells, while overexpression of the Drosophila homolog of WIPI1, Atg18a, extended the life span in transgenic flies. Interestingly, the enhanced autophagy-lysosomal activity could be partially passed on to their offspring, as manifested by their higher levels of both autophagy-encoding genes and serum beclin 1 (BECN1). In light of the normal age-related decline of autophagy-lysosomal functions, these findings provide a compelling explanation for achieving longevity in, at least, female CENs, given the gender bias in our collected samples, and suggest that the enhanced waste-cleaning activity via autophagy may serve as a conserved mechanism to prolong the life span from Drosophila to humans.


Asunto(s)
Autofagia/genética , Longevidad/genética , Transcriptoma , Anciano , Anciano de 80 o más Años , Proteínas Relacionadas con la Autofagia/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Beclina-1/genética , Beclina-1/metabolismo , Catepsina B/genética , Catepsina B/metabolismo , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Femenino , Humanos , Lisosomas/metabolismo , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , ATPasas de Translocación de Protón Vacuolares/genética , ATPasas de Translocación de Protón Vacuolares/metabolismo
5.
Virol J ; 18(1): 26, 2021 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-33485391

RESUMEN

BACKGROUND: Herpes Simplex Virus type I (HSV-1) is a large double-stranded DNA virus that enters productive infection in epithelial cells and reorganizes the host nucleus. Cohesin, a major constituent of interphase and mitotic chromosomes comprised of SMC1, SMC3, and SCC1 (Mcd1/Rad21), SCC3 (SA1/SA2), have diverse functions, including sister chromatid cohesion, DNA double-stranded breaks repair, and transcriptional control. Little is known about the role of cohesin in HSV-1 lytic infection. METHODS: We measured the effect on HSV-1 transcription, genome copy number, and viral titer by depleting cohesin components SMC1 or Rad21 using RNAi, followed by immunofluorescence, qPCR, and ChIP experiments to gain insight into cohesin's function in HSV-1 transcription and replication. RESULTS: Here, we report that cohesion subunits SMC1 and Rad21 are recruited to the lytic HSV-1 replication compartment. The knockdown results in decreased viral transcription, protein expression, and maturation of viral replication compartments. SMC1 and Rad21 knockdown leads to the reduced overall RNA pol II occupancy level but increased RNA pol II ser5 phosphorylation binding on viral genes. Consistent with this, the knockdown increased H3K27me3 modification on these genes. CONCLUSIONS: These results suggest that cohesin facilitates HSV-1 lytic transcription by promoting RNA Pol II transcription activity and preventing chromatin's silencing on the viral genome.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Fibroblastos/virología , Herpesvirus Humano 1/genética , ARN Polimerasa II/metabolismo , Transcripción Genética , Proteínas de Ciclo Celular/clasificación , Proteínas de Ciclo Celular/genética , Línea Celular , Proteínas Cromosómicas no Histona/clasificación , Proteínas Cromosómicas no Histona/genética , Proteínas de Unión al ADN/metabolismo , Genoma Viral , Células HeLa , Interacciones Microbiota-Huesped , Humanos , Proteínas Nucleares/metabolismo , Unión Proteica , Cohesinas
6.
J Neurovirol ; 26(3): 391-403, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32301037

RESUMEN

Herpes simplex virus type I (HSV-1) infection causes inflammation in the cornea known as herpes simplex virus keratitis (HSK), a common but serious corneal disease. It is not entirely clear whether the virus during recurring infection comes from the trigeminal ganglia or the eye tissue, including the retina and ciliary ganglion. Because the tree shrew is closely related to primates and tree shrew eye anatomic structures are similar to humans, we studied HSV-1 corneal infection in the tree shrew. We found that HSK symptoms closely mimic those found in human HSK showing typical punctiform and dendritic viral keratitis during the acute infection period. Following the HSV-specific lesions, complications such as stromal scarring, corneal thickening (primary infection), opacity, and neovascularization were observed. In the tree shrew model, following ocular inoculation, the cornea becomes infected, and viral protein can be detected using anti-HSV-1 antibodies in the epithelial layer and retina neuronal ganglion cells. The HSV-1 transcripts, ICP0, ICP4, and LAT can be detected at 3 days post-infection (dpi), peaking at 5 dpi. After 2 weeks, ICP4 and ICP0 transcripts are reduced to a basal level, but the Latency Associated Transcripts (LATs) continue to accumulate. Interestingly, after the acute infection, we still detected abundant active HSV-1 in tree shrew eyes. Further, we found HSV-1 persistent in the ciliary ganglion and cornea. These findings are discussed in support of the tree shrew as a non-human primate HSK model, which could be useful for mechanistic studies of HSK.


Asunto(s)
Córnea/virología , Regulación Viral de la Expresión Génica , Herpes Simple/virología , Herpesvirus Humano 1/genética , Queratitis Herpética/virología , Neovascularización Patológica/virología , Animales , Córnea/patología , Modelos Animales de Enfermedad , Femenino , Ganglios Parasimpáticos/patología , Ganglios Parasimpáticos/virología , Herpes Simple/patología , Herpesvirus Humano 1/crecimiento & desarrollo , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 1/patogenicidad , Humanos , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Queratitis Herpética/patología , MicroARNs/genética , MicroARNs/metabolismo , Neovascularización Patológica/patología , Neuronas/patología , Neuronas/virología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ganglio del Trigémino/patología , Ganglio del Trigémino/virología , Tupaia , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Latencia del Virus
8.
Virol J ; 17(1): 95, 2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32641145

RESUMEN

BACKGROUND: Following acute infection, Herpes Simplex virus-1 (HSV-1) establishes lifelong latency and recurrent reactivation in the sensory neurons of trigeminal ganglia (TG). Infected tree shrew differs from mouse and show characteristics similar to human infection. A detailed transcriptomic analysis of the tree shrew model could provide mechanistic insights into HSV-1 infection in humans. METHODS: We sequenced the transcriptome of infected TGs from tree shrews and mice, and 4 human donors, then examined viral genes expression up to 58 days in infected TGs from mouse and tree shrew, and compare the latency data with that in human TGs. RESULTS: Here, we found that all HSV-1 genes could be detected in mouse TGs during acute infection, but 22 viral genes necessary for viral transcription, replication and viral maturation were not expressed in tree shrew TGs during this stage. Importantly, during latency, we found that LAT could be detected both in mouse and tree shrew, but the latter also has an ICP0 transcript signal absent in mouse but present in human samples. Importantly, we observed that infected human and tree shrew TGs have a more similar LAT region transcription peak. More importantly, we observed that HSV-1 spontaneously reactivates from latently infected tree shrews with relatively high efficiency. CONCLUSIONS: These results represent the first longitudinal transcriptomic characterization of HSV-1 infection in during acute, latency and recurrent phases, and revealed that tree shrew infection has important similar features with human infection.


Asunto(s)
Genes Virales , Herpes Simple/veterinaria , Herpesvirus Humano 1/genética , Transcriptoma , Ganglio del Trigémino/virología , Tupaiidae/virología , Enfermedad Aguda , Adulto , Animales , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Herpes Simple/virología , Herpesvirus Humano 1/fisiología , Humanos , Estudios Longitudinales , Masculino , Ratones , Ratones Endogámicos BALB C , RNA-Seq , Proteínas Virales/genética , Latencia del Virus , Replicación Viral
9.
Proc Natl Acad Sci U S A ; 114(41): 10912-10917, 2017 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-28973861

RESUMEN

CTCF is an essential epigenetic regulator mediating chromatin insulation, long-range regulatory interactions, and the organization of large topological domains in the nucleus. Phenotypes of CTCF haploinsufficient mutations in humans, knockout in mice, and depletion in cells are often consistent with impaired genome stability, but a role of CTCF in genome maintenance has not been fully investigated. Here, we report that CTCF maintains genome stability, is recruited to sites of DNA damage, and promotes homologous recombination repair of DNA double-strand breaks (DSBs). CTCF depletion increased chromosomal instability, marked by chromosome breakage and end fusions, elevated genotoxic stress-induced genomic DNA fragmentation, and activated the ataxia telangiectasia mutated (ATM) kinase. We show that CTCF could be recruited to drug-induced 53BP1 foci and known fragile sites, as well as to I-SceI endonuclease-induced DSBs. Laser irradiation analysis revealed that this recruitment depends on ATM, Nijmegen breakage syndrome (NBS), and the zinc finger DNA-binding domain of CTCF. We demonstrate that CTCF knockdown impaired homologous recombination (HR) repair of DSBs. Consistent with this, CTCF knockdown reduced the formation of γ-radiation-induced Rad51 foci, as well as the recruitment of Rad51 to laser-irradiated sites of DNA lesions and to I-SceI-induced DSBs. We further show that CTCF is associated with DNA HR repair factors MDC1 and AGO2, and directly interacts with Rad51 via its C terminus. These analyses establish a direct, functional role of CTCF in DNA repair and provide a potential link between genome organization and genome stability.


Asunto(s)
Factor de Unión a CCCTC/metabolismo , Daño del ADN , Inestabilidad Genómica , Osteosarcoma/genética , Reparación del ADN por Recombinación , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Factor de Unión a CCCTC/antagonistas & inhibidores , Factor de Unión a CCCTC/genética , Humanos , Osteosarcoma/metabolismo , Osteosarcoma/patología , ARN Interferente Pequeño/genética , Recombinasa Rad51/genética , Recombinasa Rad51/metabolismo , Células Tumorales Cultivadas
10.
Virol J ; 16(1): 17, 2019 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-30717754

RESUMEN

In the original publication of this article [1], two grants from National Science Foundation of China and Yunnan Provincial Government (U1602226) and by National Science Foundation of China (2016YFC1200404) were omitted in the 'Funding' section. The correct 'Funding' section is below.

11.
Virol J ; 14(1): 217, 2017 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-29116029

RESUMEN

BACKGROUND: The Zika virus (ZIKV) is a mosquito-borne flavivirus that causes microcephaly and Guillain-Barré syndrome in infected individuals. To obtain insights into the mechanism of ZIKV infection and pathogenesis, we analyzed the transcriptome of ZIKV infected human neural progenitor cells (hNPCs) for changes in alternative splicing (AS), gene isoform (ISO) composition and long noncoding RNAs (lncRNAs) expression. METHODS: We analyzed differentially expressed lncRNAs, AS, ISO from RNA-seq data in ZIKV infected hNPCs. RESULTS: We obtained 149 differentially expressed lncRNAs, including potential viral targets to modulate cellular processes such as cell cycle, apoptosis and immune response. The infection induced 262 cases of AS occurring in 229 genes, which were enriched in cell death, RNA processing, transport, and neuron development. Among 691 differentially expressed ISOs, upregulated ISOs were enriched in signaling, regulation of transcription, and amino acid biosynthesis, while downregulated ISOs were mostly enriched in cell cycle. Importantly, these analyses revealed specific links between ZIKV induced changes in cellular pathways and the type of changes in the host transcriptome, suggesting important regulatory mechanisms. CONCLUSIONS: Our analyses revealed candidate lncRNAs, AS events and ISOs which may function in ZIKV infection induced cell cycle disruption, apoptosis and attenuation of neurogenesis, and shed light on the roles of lncRNAs, AS and ISOs in virus-host interactions, and would facilitate future studies of ZIKV infection and pathogenesis.


Asunto(s)
Empalme Alternativo/genética , Células-Madre Neurales/virología , Infección por el Virus Zika/virología , Virus Zika/genética , Apoptosis , Ciclo Celular , Bases de Datos de Ácidos Nucleicos , Perfilación de la Expresión Génica , Ontología de Genes , Interacciones Huésped-Patógeno/genética , Humanos , Isoformas de Proteínas/genética , ARN Largo no Codificante/genética , Transcriptoma
12.
Virol J ; 13: 137, 2016 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-27496175

RESUMEN

BACKGROUND: One of the most important functions of long noncoding RNAs (lncRNAs) is to control protein coding gene transcription by acting locally in cis, or remotely in trans. Herpes Simplex Virus type I (HSV-1) latently infects over 80 % of the population, its reactivation from latency usually results in productive infections in human epithelial cells, and is responsible for the common cold sores and genital Herpes. HSV-1 productive infection leads to profound changes in the host cells, including the host transcriptome. However, how genome wide lncRNAs expressions are affected by the infection and how lncRNAs expression relates to protein coding gene expression have not been analyzed. METHODS: We analyzed differentially expressed lncRNAs and their potential targets from RNA-seq data in HSV-1 infected human foreskin fibroblast (HFF) cells. Based on correlations of expression patterns of differentially expressed protein-coding genes and lncRNAs, we predicted that these lncRNAs may regulate, either in cis or in trans, the expression of many cellular protein-coding genes. RESULTS: Here we analyzed HSV-1 infection induced, differentially expressed lncRNAs and predicted their target genes. We detected 208 annotated and 206 novel differentially expressed lncRNAs. Gene Ontology and Pathway enrichment analyses revealed potential lncRNA targets, including genes in chromatin assembly, genes in neuronal development and neurodegenerative diseases and genes in the immune response, such as Toll-like receptor signaling and RIG-I-like receptor signaling pathways. CONCLUSIONS: We found that differentially expressed lncRNAs may regulate the expression of many cellular protein-coding genes involved in pathways from native immunity to neuronal development, thus revealing important roles of lncRNAs in the regulation of host transcriptional programs in HSV-1 infected human cells.


Asunto(s)
Fibroblastos/metabolismo , Prepucio/virología , Herpes Simple/genética , Herpesvirus Humano 1/fisiología , ARN Largo no Codificante/genética , Fibroblastos/virología , Prepucio/metabolismo , Regulación de la Expresión Génica , Herpes Simple/metabolismo , Herpes Simple/virología , Herpesvirus Humano 1/genética , Humanos , Masculino , ARN Largo no Codificante/metabolismo
13.
Virol J ; 13: 65, 2016 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-27062411

RESUMEN

BACKGROUND: Replication of viral genome is the central event during the lytic infectious cycle of herpes simplex virus 1 (HSV-1). However, the details of HSV-1 replication process are still elusive due to the limitations of current molecular and conventional fluorescent microscopy methods. Stimulated emission depletion (STED) microscopy is one of the recently available super-resolution techniques allowing observation at sub-diffraction resolution. METHODS: To gain new insight into HSV-1 replication, we used a combination of stimulated emission depletion microscopy, fluorescence in situ hybridization (FISH) and immunofluorescence (IF) to observe the HSV-1 replication process. RESULTS: Using two colored probes labeling the same region of HSV-1 genome, the two probes highly correlated in both pre-replication and replicating genomes. In comparison, when probes from different regions were used, the average distance between the two probes increased after the virus enters replication, suggesting that the HSV-1 genome undergoes dynamic structure changes from a compact to a relaxed formation and occupies larger space as it enters replication. Using FISH and IF, viral single strand binding protein ICP8 was seen closely positioned with HSV-1 genome. In contrast, ICP8 and host RNA polymerase II were less related. This result suggests that ICP8 marked regions of DNA replication are spatially separated from regions of active transcription, represented by the elongating form of RNA polymerase II within the viral replication compartments. Comparing HSV-1 genomes at early stage of replication with that in later stage, we also noted overall increases among different values. These results suggest stimulated emission depletion microscopy is capable of investigating events during HSV-1 replication. CONCLUSION: 1) Replicating HSV-1 genome could be observed by super-resolution microscopy; 2) Viral genome expands spatially during replication; 3) Viral replication and transcription are partitioned into different sub-structures within the replication compartments.


Asunto(s)
Herpesvirus Humano 1/fisiología , Microscopía/métodos , Replicación Viral , Células Cultivadas , Fibroblastos/virología , Humanos
14.
Adv Mater ; 36(24): e2314346, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38582970

RESUMEN

Electrowetting-on-dielectric (EWOD), recognized as the most successful electrical droplet actuation method, is essential in diverse applications, ranging from thermal management to microfluidics and water harvesting. Despite significant advances, it remains challenging to achieve repeatability, high speed, and simple circuitry in EWOD-based droplet manipulation on superhydrophobic surfaces. Moreover, its efficient operation typically requires electrode arrays and sophisticated circuit control. Here, a newly observed droplet manipulation phenomenon on superhydrophobic surfaces with orbital EWOD (OEW) is reported. Due to the asymmetric electrowetting force generated on the orbit, flexible and versatile droplet manipulation is facilitated with OEW. It is demonstrated that OEW droplet manipulation on superhydrophobic surfaces exhibits higher speed (up to 5 times faster), enhanced functionality (antigravity), and manipulation of diverse liquids (acid, base, salt, organic, e.g., methyl blue, artificial blood) without contamination, and good durability after 1000 tests. It is envisioned that this robust droplet manipulation strategy using OEW will provide a valuable platform for various processes involving droplets, spanning from microfluidic devices to controllable chemical reactions. The previously unreported droplet manipulation phenomenon and control strategy shown here can potentially upgrade EWOD-based microfluidics, antifogging, anti-icing, dust removal, and beyond.

15.
Virol Sin ; 38(1): 108-118, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36436797

RESUMEN

Herpes simplex virus-1 (HSV-1) is a widespread neurotropic virus that can reach the brain and cause a rare but acute herpes simplex encephalitis (HSE) with a high mortality rate. Most patients present with changes in neurological and behavioral status, and survivors suffer long-term neurological sequelae. To date, the pathogenesis leading to brain damage is still not well understood. HSV-1 induced encephalitis in the central nervous system (CNS) in animals are usually very diffuse and progressing rapidly, and mostly fatal, making the analysis difficult. Here, we established a mouse model of HSE via intracerebral inoculation of modified version of neural-attenuated strains of HSV-1 (deletion of ICP34.5 and inserting a strong promoter into the latency-associated transcript region), in which the LMR-αΔpA strain initiated moderate productive infection, leading to strong host immune and inflammatory response characterized by persistent microglia activation. This viral replication activity and prolonged inflammatory response activated signaling pathways in neuronal damage, amyloidosis, Alzheimer's disease, and neurodegeneration, eventually leading to neuronal loss and behavioral changes characterized by hypokinesia. Our study reveals detailed pathogenic processes and persistent inflammatory responses in the CNS and provides a controlled, mild and non-lethal HSE model for studying long-term neuronal injury and increased risk of neurodegenerative diseases due to HSV-1 infection.


Asunto(s)
Encefalitis por Herpes Simple , Herpes Simple , Herpesvirus Humano 1 , Ratones , Animales , Herpesvirus Humano 1/fisiología , Encefalitis por Herpes Simple/complicaciones , Encefalitis por Herpes Simple/patología , Encéfalo/patología , Inflamación
16.
J Gerontol A Biol Sci Med Sci ; 78(12): 2251-2259, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37738989

RESUMEN

Aging of the organism is associated diminished response to external stimuli including weakened immune function, resulting in diseases that impair health and lifespan. Several dietary restriction modalities have been reported to improve health and lifespan in different animal models, but it is unknown whether any of the lifespan-extending dietary treatments could be combined to achieve an additive effect. Here, we investigated the effects of halving amino acids components in the HUNTaa diet, a synthetic medium known to extend lifespan in Drosophila. We found that dietary restriction by halving the entire amino acid components (DR group) could further extend lifespan and improve resistance to oxidative stress, desiccation stress, and starvation than flies on HUNTaa diet alone (wt group). Transcriptome analysis of Drosophila at 40, 60, and 80 days of age revealed that genes related to cell proliferation and metabolism decreased with age in the wt group, whereas background stimulus response and amino acid metabolism increased with age. However, these trends differed in the DR group, that is, the DR flies had downregulated stress response genes, including reduced background immune activation. Infection experiments demonstrated that these flies survived longer after feeding infection with Serratia marcescens and Enterococcus faecalis, suggesting that these flies had stronger immune function, and therefore reduced immune senescence. These results demonstrated that halving the entire amino acid components in the HUNTaa diet further extended health and lifespan and suggested that lifespan-extending diet and dietary restriction treatment could be combined to achieve additive beneficial results.


Asunto(s)
Drosophila melanogaster , Longevidad , Animales , Longevidad/fisiología , Drosophila melanogaster/genética , Dieta con Restricción de Proteínas , Drosophila , Aminoácidos , Restricción Calórica
17.
Brain Sci ; 12(12)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36552109

RESUMEN

Graph convolutional neural networks (GCN) have attracted much attention in the task of electroencephalogram (EEG) emotion recognition. However, most features of current GCNs do not take full advantage of the causal connection between the EEG signals in different frequency bands during the process of constructing the adjacency matrix. Based on the causal connectivity between the EEG channels obtained by Granger causality (GC) analysis, this paper proposes a multi-frequency band EEG graph feature extraction and fusion method for EEG emotion recognition. First, the original GC matrices between the EEG signals at each frequency band are calculated via GC analysis, and then they are adaptively converted to asymmetric binary GC matrices through an optimal threshold. Then, a kind of novel GC-based GCN feature (GC-GCN) is constructed by using differential entropy features and the binary GC matrices as the node values and adjacency matrices, respectively. Finally, on the basis of the GC-GCN features, a new multi-frequency band feature fusion method (GC-F-GCN) is proposed, which integrates the graph information of the EEG signals at different frequency bands for the same node. The experimental results demonstrate that the proposed GC-F-GCN method achieves better recognition performance than the state-of-the-art GCN methods, for which average accuracies of 97.91%, 98.46%, and 98.15% were achieved for the arousal, valence, and arousal-valence classifications, respectively.

18.
Front Neurosci ; 16: 974673, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36161187

RESUMEN

EEG emotion recognition based on Granger causality (GC) brain networks mainly focus on the EEG signal from the same-frequency bands, however, there are still some causality relationships between EEG signals in the cross-frequency bands. Considering the functional asymmetric of the left and right hemispheres to emotional response, this paper proposes an EEG emotion recognition scheme based on cross-frequency GC feature extraction and fusion in the left and right hemispheres. Firstly, we calculate the GC relationship of EEG signals according to the frequencies and hemispheres, and mainly focus on the causality of the cross-frequency EEG signals in left and right hemispheres. Then, to remove the redundant connections of the GC brain network, an adaptive two-stage decorrelation feature extraction scheme is proposed under the condition of maintaining the best emotion recognition performance. Finally, a multi-GC feature fusion scheme is designed to balance the recognition accuracy and feature number of each GC feature, which comprehensively considers the influence of the recognition accuracy and computational complexity. Experimental results on the DEAP emotion dataset show that the proposed scheme can achieve an average accuracy of 84.91% for four classifications, which improved the classification accuracy by up to 8.43% compared with that of the traditional same-frequency band GC features.

19.
Front Neurorobot ; 16: 995552, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36247357

RESUMEN

Objective: Brain-computer interface (BCI) can translate intentions directly into instructions and greatly improve the interaction experience for disabled people or some specific interactive applications. To improve the efficiency of BCI, the objective of this study is to explore the feasibility of an audio-assisted visual BCI speller and a deep learning-based single-trial event related potentials (ERP) decoding strategy. Approach: In this study, a two-stage BCI speller combining the motion-onset visual evoked potential (mVEP) and semantically congruent audio evoked ERP was designed to output the target characters. In the first stage, the different group of characters were presented in the different locations of visual field simultaneously and the stimuli were coded to the mVEP based on a new space division multiple access scheme. And then, the target character can be output based on the audio-assisted mVEP in the second stage. Meanwhile, a spatial-temporal attention-based convolutional neural network (STA-CNN) was proposed to recognize the single-trial ERP components. The CNN can learn 2-dimentional features including the spatial information of different activated channels and time dependence among ERP components. In addition, the STA mechanism can enhance the discriminative event-related features by adaptively learning probability weights. Main results: The performance of the proposed two-stage audio-assisted visual BCI paradigm and STA-CNN model was evaluated using the Electroencephalogram (EEG) recorded from 10 subjects. The average classification accuracy of proposed STA-CNN can reach 59.6 and 77.7% for the first and second stages, which were always significantly higher than those of the comparison methods (p < 0.05). Significance: The proposed two-stage audio-assisted visual paradigm showed a great potential to be used to BCI speller. Moreover, through the analysis of the attention weights from time sequence and spatial topographies, it was proved that STA-CNN could effectively extract interpretable spatiotemporal EEG features.

20.
ACS Nano ; 14(11): 15394-15402, 2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-33179494

RESUMEN

Aquatic microbots have drawn great research interest due to the demands in aquatic environmental monitoring, inspection, and confined space exploration. Current actuation methods heavily rely on mechanical motion powered by large-amplitude and high-frequency sources, which limit the applications with portability and concealment requirements. Herein we propose a triboelectric nanogenerator (TENG)-enabled electrowetting-on-dielectric (EWOD) actuator (TENG-EWA) for aquatic microbots. The transferred tribo-charges of a disc TENG alternatively modify the surface energy of the EWOD actuator, yielding a capillary wave propagation. The reaction force of the capillary wave actuates the microbot on the water surface. The characteristics of the TENG induced capillary wave are analyzed experimentally and modeled theoretically. An optical transparent microbot (weight of 0.07 g, body length of 1 cm) was actuated forward at a maximum locomotion velocity of 1 cm/s. Diverse locomotion functions are demonstrated: with a load of 3 times to the robot net weight, in seawater, at a silicone-oil/deionized water interface. Besides, the locomotion of the microbot was demonstrated by a wind-driven TENG, and a good concealment performance was achieved under infrared camera and decibel meter. The proposed aquatic TENG-Bot not only shows the potential of converting environmental energy into actuation force for microbots but also reveals advantages in optical, sonic, and infrared concealment.

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