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1.
Front Pharmacol ; 15: 1382256, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957393

RESUMO

Hepatocellular carcinoma (HCC) is one of the cancers that seriously threaten human health. Immunotherapy serves as the mainstay of treatment for HCC patients by targeting the programmed cell death protein 1/programmed cell death 1 ligand 1 (PD-1/PD-L1) axis. However, the effectiveness of anti-PD-1/PD-L1 treatment is limited when HCC becomes drug-resistant. Tumor-associated macrophages (TAMs) are an important factor in the negative regulation of PD-1 antibody targeted therapy in the tumor microenvironment (TME). Therefore, as an emerging direction in cancer immunotherapy research for the treatment of HCC, it is crucial to elucidate the correlations and mechanisms between TAMs and PD-1/PD-L1-mediated immune tolerance. This paper summarizes the effects of TAMs on the pathogenesis and progression of HCC and their impact on HCC anti-PD-1/PD-L1 immunotherapy, and further explores current potential therapeutic strategies that target TAMs in HCC, including eliminating TAMs in the TME, inhibiting TAMs recruitment to tumors and functionally repolarizing M2-TAMs (tumor-supportive) to M1-TAMs (antitumor type).

2.
Microsyst Nanoeng ; 10: 97, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015940

RESUMO

Exosomes derived from mesenchymal stem cells (MSCs) have been confirmed to enhance cell proliferation and improve tissue repair. Exosomes release their contents into the cytoplasmic solution of the recipient cell to mediate cell expression, which is the main pathway through which exosomes exert therapeutic effects. The corresponding process of exosome internalization mainly occurs in the early stage of treatment. However, the therapeutic effect of exosomes in the early stage remains to be further studied. We report that the three-dimensional cell traction force can intuitively reflect the ability of exosomes to enhance the cytoskeleton and cell contractility of recipient cells, serving as an effective method to characterize the therapeutic effect of exosomes. Compared with traditional biochemical methods, we can visualize the early therapeutic effect of exosomes in real time without damage by quantifying the cell traction force. Through quantitative analysis of traction forces, we found that endometrial stromal cells exhibit short-term cell roundness accompanied by greater traction force during the early stage of exosome therapy. Further experiments revealed that exosomes enhance the traction force and cytoskeleton by regulating the Rac1/RhoA signaling pathway, thereby promoting cell proliferation. This work provides an effective method for rapidly quantifying the therapeutic effects of exosomes and studying the underlying mechanisms involved.

3.
Front Vet Sci ; 11: 1431879, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38983770

RESUMO

Senecavirus A (SVA) is an emerging virus that causes the vesicular disease in pigs, clinically indistinguishable from other high consequence vesicular diseases. This virus belongs to the genus Senecavirus in the family Picornaviridae. Its genome is a positive-sense, single-stranded RNA, approximately 7,300 nt in length, with a 3' poly(A) tail but without 5'-end capped structure. SVA can efficiently propagate in different cells, including some non-pig-derived cell lines. A wild-type SVA was previously rescued from its cDNA clone using reverse genetics in our laboratory. In the present study, the BSR-T7/5 cell line was inoculated with the passage-5 SVA. At 12 h post-inoculation, SVA-infected and non-infected cells were independently collected for the analysis on comparative transcriptomics. The results totally showed 628 differentially expressed genes, including 565 upregulated and 63 downregulated ones, suggesting that SVA infection significantly stimulated the transcription initiation in cells. GO and KEGG enrichment analyses demonstrated that SVA exerted multiple effects on immunity-related pathways in cells. Furthermore, the RNA sequencing data were subjected to other in-depth analyses, such as the single-nucleotide polymorphism, transcription factors, and protein-protein interactions. The present study, along with our previous proteomics and metabolomics researches, provides a multi-omics insight into the interaction between SVA and its hosts.

4.
Small ; : e2401596, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38889398

RESUMO

All inorganic lead halide perovskites exhibit fascinating optical and optoelectronic characteristics for on-chip lasing, but the lack of precise control of wafer-scale fabrication for perovskite microstructure arrays restricts their potential applications in on-chip-integrated devices. In this work, a microstructure-template assisted crystallization method is demonstrated via a designed chemical vapor deposition process, achieving the controllable fabrication of homogeneous perovskite micro-hemispheroid (PeMH) arrays spanning the entire surface area of a 4-inch wafer. Benefiting from the low-loss whispering gallery resonance and plasmon-enhanced light-matter interactions in well-confined hybrid cavities, this CsPbX3/Ag (X = Cl, Br) plasmonic microlasers exhibit quite low thresholds below 10 µJ cm-2. Interestingly, these thresholds can be efficiently modulated through the manipulation of plasmonic resonance and electromagnetic field mode in PeMHs owning various diameters. This strategy not only provides a valuable methodology for the large-scale fabrication of perovskite microstructures but also endorses the potential of all-inorganic perovskite nanostructures as promising candidates for on-chip-integrated light sources.

5.
Sensors (Basel) ; 24(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38894098

RESUMO

Bolts have the advantages of simple installation and easy removal. They are widely applied in aerospace and high-speed railway traffic. However, the loosening of bolts under mixed loads can lead to nonlinear decreases in pre-loading. This affects the safety performance of the structure and may lead to catastrophic consequences. Existing techniques cannot be used to monitor the bolt performance status in time. This has caused significant problems with the safety and reliability of equipment. In order to study the relaxation law of bolt pre-loading, this paper carries out an experimental analysis for 8.8-grade hexagonal bolts and calibrates the torque coefficient. We also studied different loading waveforms, nickel steel plate surface roughnesses, tangential displacement frequencies, four different strengths and bolt head contact areas of the bolt, the initial pre-loading, and the effects of tangential cyclic displacement on pre-loading relaxation. This was done in order to accurately predict the degree of bolt pre-loading loosening under external loads. The laws are described using the allometric model function and the nine-stage polynomial function. The least squares method is used to identify the parameters in the function. The results show that bolts with a smooth surface of the connected structure nickel steel flat plate, high-frequency working conditions, half-sine wave, and a high-strength have better anti-loosening properties. Taking 5-10 cycles of cyclic loading as a boundary, the pre-loading relaxation is divided into two stages. The first stage is a stage of rapid decrease in bolt pre-loading, and the second stage is the slow decrease process. The performance prediction study shows that the allometric model function is the worst fitted, at 71.7% for the small displacement condition. Other than that, the allometric model function and the nine-stage polynomial function can predict more than 85.5% and 90.4%, which require the use of least squares to identify two and ten unknown parameters, respectively. The complexity of the two is different, but both can by better indicators than the pre-loading relaxation law under specific conditions. It helps to improve the monitoring of bolt loosening and the system use cycle, and it can provide theoretical support for complex equipment working for a long time.

6.
Cell Rep ; 43(6): 114366, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38879877

RESUMO

p53 regulates multiple signaling pathways and maintains cell homeostasis under conditions of DNA damage and oxidative stress. Although USP7 has been shown to promote p53 stability via deubiquitination, the USP7-p53 activation mechanism has remained unclear. Here, we propose that DNA damage induces reactive oxygen species (ROS) production and activates ATM-CHK2, and CHK2 then phosphorylates USP7 at S168 and T231. USP7 phosphorylation is essential for its deubiquitination activity toward p53. USP7 also deubiquitinates CHK2 at K119 and K131, increasing CHK2 stability and creating a positive feedback loop between CHK2 and USP7. Compared to peri-tumor tissues, thyroid cancer and colon cancer tissues show higher CHK2 and phosphorylated USP7 (S168, T231) levels, and these levels are positively correlated. Collectively, our results uncover a phosphorylation-deubiquitination positive feedback loop involving the CHK2-USP7 axis that supports the stabilization of p53 and the maintenance of cell homeostasis.


Assuntos
Quinase do Ponto de Checagem 2 , Estresse Oxidativo , Proteína Supressora de Tumor p53 , Peptidase 7 Específica de Ubiquitina , Ubiquitinação , Quinase do Ponto de Checagem 2/metabolismo , Peptidase 7 Específica de Ubiquitina/metabolismo , Humanos , Proteína Supressora de Tumor p53/metabolismo , Fosforilação , Retroalimentação Fisiológica , Dano ao DNA , Espécies Reativas de Oxigênio/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral , Estabilidade Proteica , Animais
7.
Org Lett ; 26(26): 5453-5457, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38913009

RESUMO

A copper-catalyzed intramolecular cascade reaction of conjugated enynones has been achieved via a pivotal 1,4-sulfinate migration step. This process leverages a cost-effective and ecofriendly copper salt as catalyst, enabling the efficient construction of five- and four-membered rings in a rapid, sequential manner, producing furan-tethered benzocyclobutenes in good to excellent yields under mild conditions. The reaction is characterized by 100% atom economy, outstanding efficiency, and excellent diastereoselectivity in the cases studied. The robustness of this method is evidenced by its compatibility with air exposure and the use of undistilled, commercially available solvents, further enhancing its practicality.

8.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38944841

RESUMO

Four new alkaloids, arecatines A-D (1-4), were isolated from the peels of Areca catechu. Compound 1 is an unusual piperidine-pyridine hybrid alkaloid, whereas compounds 2-4 feature bis-piperidine alkaloids. Their structures were elucidated by UV, IR, HRESIMS, and NMR spectra analysis. The molecular docking analysis indicated that compound 3 exhibited the best binding affinity with the GABAA receptor, indicating its potential anti-epilepsy activity.

9.
J Nanobiotechnology ; 22(1): 351, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902789

RESUMO

Spinal cord injury (SCI) often results in motor and sensory deficits, or even paralysis. Due to the role of the cascade reaction, the effect of excessive reactive oxygen species (ROS) in the early and middle stages of SCI severely damage neurons, and most antioxidants cannot consistently eliminate ROS at non-toxic doses, which leads to a huge compromise in antioxidant treatment of SCI. Selenium nanoparticles (SeNPs) have excellent ROS scavenging bioactivity, but the toxicity control problem limits the therapeutic window. Here, we propose a synergistic therapeutic strategy of SeNPs encapsulated by ZIF-8 (SeNPs@ZIF-8) to obtain synergistic ROS scavenging activity. Three different spatial structures of SeNPs@ZIF-8 were synthesized and coated with ferrostatin-1, a ferroptosis inhibitor (FSZ NPs), to achieve enhanced anti-oxidant and anti-ferroptosis activity without toxicity. FSZ NPs promoted the maintenance of mitochondrial homeostasis, thereby regulating the expression of inflammatory factors and promoting the polarization of macrophages into M2 phenotype. In addition, the FSZ NPs presented strong abilities to promote neuronal maturation and axon growth through activating the WNT4-dependent pathways, while prevented glial scar formation. The current study demonstrates the powerful and versatile bioactive functions of FSZ NPs for SCI treatment and offers inspiration for other neural injury diseases.


Assuntos
Antioxidantes , Nanopartículas , Espécies Reativas de Oxigênio , Selênio , Traumatismos da Medula Espinal , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Antioxidantes/farmacologia , Antioxidantes/química , Nanopartículas/química , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Selênio/química , Selênio/farmacologia , Neurônios/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Ratos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Células RAW 264.7 , Regeneração Nervosa/efeitos dos fármacos
10.
Opt Express ; 32(8): 13095-13110, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859288

RESUMO

Modulation format recognition (MFR) is a key technology for adaptive optical systems, but it faces significant challenges in underwater visible light communication (UVLC) due to the complex channel environment. Recent advances in deep learning have enabled remarkable achievements in image recognition, owing to the powerful feature extraction of neural networks (NN). However, the high computational complexity of NN limits their practicality in UVLC systems. This paper proposes a communication-informed knowledge distillation (CIKD) method that achieves high-precision and low-latency MFR with an ultra-lightweight student model. The student model consists of only one linear dense layer under a communication-informed auxiliary system and is trained under the guidance of a high-complexity and high-precision teacher model. The MFR task involves eight modulation formats: PAM4, QPSK, 8QAM-CIR, 8QAM-DIA, 16QAM, 16APSK, 32QAM, and 32APSK. Experimental results show that the student model based on CIKD can achieve comparable accuracy to the teacher model. After knowledge transfer, the prediction accuracy of the student model can be increased by up to 87%. Besides, it is worth noting that CIKD's inference accuracy can reach up to 100%. Moreover, the parameters constituting the student model in CIKD correspond to merely 18% of the parameters found in the teacher model, which facilitates the hardware deployment and online data processing of MFR algorithms in UVLC systems.

11.
ACS Nano ; 18(27): 17361-17368, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38913031

RESUMO

Lithium-air batteries (LABs) have aroused worldwide interest due to their high energy density as a promising next-generation battery technology. From a practical standpoint, one of the most pressing issues currently in LABs is their poor rate performance. Accelerating the mass transfer rate within LABs is a crucial aspect for enhancing their rate capability. In this Perspective, we have meticulously analyzed the ion and oxygen transport processes to provide readers with a comprehensive understanding of the mass transfer within LABs. Following this, we have discussed potential misconceptions in the existing literature and propose our recommendations for improving the rate performance of LABs. This Perspective provides a deep insight into the mass transfer process in LABs and offers promising strategies for developing other high-rate metal-O2 batteries.

12.
Eur J Pharm Biopharm ; 201: 114350, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38848783

RESUMO

Ginsenoside (GS), one of the main active components in ginseng, can enhance insulin sensitivity, improve the function of islet ß cells, and reduce cell apoptosis in the treatment of diabetes. However, the drawbacks of high lipid solubility, poor water solubility, and low oral availability in Ginsenoside Rg3 (G-Rg3) seriously limit further application of GS. In this work, a G-Rg3 PEGylated long-circulating liposome (PEG-L-Rg3) is designed and developed to improve symptoms in type 2 diabetic mice. The as-prepared PEG-L-Rg3 with a spherical structure shows a particle size of âˆ¼ 140.5 ± 1.4 nm, the zeta potential of -0.10 ± 0.05 mV, and a high encapsulation rate of 99.8 %. Notably, in vivo experimental results demonstrate that PEG-L-Rg3 exhibits efficient ability to improve body weight and food intake in streptozotocin-induced type 2 diabetic mice. Moreover, PEG-L-Rg3 also enhances fasting insulin (FINS) and insulin sensitivity index (ISI). In addition, the glucose tolerance of mice is significantly improved after the treatment of PEG-L-Rg3, indicating that PEG-L-Rg3 can be a potential drug for the treatment of type 2 diabetes, which provides a new way for the treatment of type 2 diabetes using ginsenosides.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Ginsenosídeos , Hiperglicemia , Resistência à Insulina , Lipossomos , Polietilenoglicóis , Animais , Ginsenosídeos/administração & dosagem , Ginsenosídeos/farmacologia , Ginsenosídeos/química , Camundongos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Experimental/tratamento farmacológico , Polietilenoglicóis/química , Masculino , Hiperglicemia/tratamento farmacológico , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Estreptozocina , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Insulina , Tamanho da Partícula
13.
Updates Surg ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839724

RESUMO

The current study aimed to investigate whether previous abdominal surgery (PAS) could affect the outcomes of colorectal cancer (CRC) surgery. We conducted the search strategy in three databases (PubMed, Embase, and the Cochrane Library) from inception to May 26, 2022. The short-term and long-term outcomes were compared between the PAS group and the non-PAS group. Odds ratios (ORs) and 95% confidence intervals (CIs) were pooled up. Stata (V.16.0) software was used for data analysis. We included 34,827 patients from 14 studies in the current study. After pooling up all the data, we found that there were higher proportions of overall complications (OR = 1.12, I2 = 4.65%, 95% CI 1.03 to 1.23, P = 0.01), ileus (OR = 1.96, I2 = 59.74%, 95% CI 1.12 to 3.44, P = 0.02) and mortality (OR = 1.26, I2 = 0.00%, 95% CI 1.11 to 1.42, P = 0.00) in the PAS group than the non-PAS group. Patients with a history of PAS had higher risks of overall complications and death following CRC surgery. However, it did not appear to significantly affect the short-term outcomes apart from ileus. Surgeons should raise awareness of patients with a history of PAS, and take steps to reduce postoperative complications and mortality.

14.
J Transl Med ; 22(1): 546, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849907

RESUMO

BACKGROUND: The pathogenesis of thyroid-associated orbitopathy (TAO) remains incompletely understand. The interaction between immunocytes and orbital fibroblasts (OFs) play a critical role in orbital inflammatory and fibrosis. Accumulating reports indicate that a significant portion of plasma exosomes (Pla-Exos) are derived from immune cells; however, their impact upon OFs function is unclear. METHODS: OFs were primary cultured from inactive TAO patients. Exosomes isolated from plasma samples of patients with active TAO and healthy controls (HCs) were utilized for functional and RNA cargo analysis. Functional analysis in thymocyte differentiation antigen-1+ (Thy-1+) OFs measured expression of inflammatory and fibrotic markers (mRNAs and proteins) and cell activity in response to Pla-Exos. RNA cargo analysis was performed by RNA sequencing and RT-qPCR. Thy-1+ OFs were transfected with miR-144-3p mimics/inhibitors to evaluate its regulation of inflammation, fibrosis, and proliferation. RESULTS: Pla-Exos derived from active TAO patients (Pla-ExosTAO-A) induced stronger production of inflammatory cytokines and hyaluronic acid (HA) in Thy-1+ OFs while inhibiting their proliferation. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and single sample gene set enrichment analysis (ssGSEA) suggested that the difference in mRNA expression levels between Pla-ExosTAO-A and Pla-ExosHC was closely related to immune cells. Differential expression analysis revealed that 62 upregulated and 45 downregulated miRNAs in Pla-ExosTAO-A, with the elevation of miR-144-3p in both Pla-Exos and PBMCs in active TAO group. KEGG analysis revealed that the target genes of differentially expressed miRNA and miR-144-3p enriched in immune-related signaling pathways. Overexpression of the miR-144-3p mimic significantly upregulated the secretion of inflammatory cytokines and HA in Thy-1+ OFs while inhibiting their proliferation. CONCLUSION: Pla-Exos derived from patients with active TAO were immune-active, which may be a long-term stimulus casual for inflammatory and fibrotic progression of TAO. Our finding suggests that Pla-Exos could be used as biomarkers or treatment targets in TAO patients.


Assuntos
Exossomos , Fibroblastos , Fibrose , Oftalmopatia de Graves , Inflamação , MicroRNAs , Órbita , Humanos , Exossomos/metabolismo , Oftalmopatia de Graves/patologia , Oftalmopatia de Graves/sangue , Oftalmopatia de Graves/genética , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/sangue , Fibroblastos/metabolismo , Fibroblastos/patologia , Órbita/patologia , Inflamação/patologia , Feminino , Masculino , Proliferação de Células , Pessoa de Meia-Idade , Adulto , Ácido Hialurônico/sangue , Ácido Hialurônico/metabolismo , Citocinas/metabolismo , Antígenos Thy-1/metabolismo
15.
Small ; : e2401939, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924354

RESUMO

3D carbon-based porous sponges are recognized for significant potential in oil absorption and electromagnetic interference (EMI). However, their widespread application is hindered by a common compromise between high performance and affordability of mass production. Herein, a novel approach is introduced that involves laser-assisted micro-zone heating melt-blown spinning (LMHMS) to address this challenge by creating pitch-based submicron carbon fibers (PSCFs) sponge with 3D interconnected structures. These structures bestow the resulting sponge exceptional characteristics including low density (≈20 mg cm-3), high porosity (≈99%), remarkable compressibility (80% maximum strain), and superior conductivity (≈628 S m-1). The resultant PSCF sponges realize an oil/organic solvent sorption capacity over 56 g/g and possess remarkable regenerated ability. In addition to their effectiveness in cleaning up oil/organic solvent spills, they also demonstrated strong electromagnetic shielding capabilities, with a total shielding effectiveness (SE) exceeding 60 dB across the X-band GHz range. In virtue of extreme lightweight of ≈20 mg cm-3, the specific SE of the PSCF sponge reaches as high as ≈1466 dB cm3 g-1, surpassing the performance of numerous carbon-based porous structures. Thus, the unique blend of properties renders these sponges promising for transforming strategies in addressing oil/organic solvent contaminations and providing effective protection against EMI.

16.
Opt Lett ; 49(10): 2805-2808, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748166

RESUMO

The advancement demands of high-speed wireless data link ask for higher requirements on visible light communication (VLC), where wide coverage stands as a critical criterion. Here, we present the design and implementation of a transmitter structure capable of emitting a high-power wide-coverage white light laser. This laser source exhibits excellent stability, with an irradiation range extending to a half-angle of 20°. Its high brightness satisfies the needs of indoor illumination while maintaining excellent communication performance. Utilizing bit-loading discrete multi-tone modulation, a peak data transmission rate of 3.24 Gbps has been achieved, spanning 1 to 5 m. Remarkably, the data rates exceed 2.5 Gbps within a 40° range at a distance of 5 m, enabling a long-distance, wide coverage, high-speed VLC link for future mobile network applications.

17.
BMC Plant Biol ; 24(1): 361, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38702620

RESUMO

BACKGROUND: Solanum muricatum is an emerging horticultural fruit crop with rich nutritional and antioxidant properties. Although the chromosome-scale genome of this species has been sequenced, its mitochondrial genome sequence has not been reported to date. RESULTS: PacBio HiFi sequencing was used to assemble the circular mitogenome of S. muricatum, which was 433,466 bp in length. In total, 38 protein-coding, 19 tRNA, and 3 rRNA genes were annotated. The reticulate mitochondrial conformations with multiple junctions were verified by polymerase chain reaction, and codon usage, sequence repeats, and gene migration from chloroplast to mitochondrial genome were determined. A collinearity analysis of eight Solanum mitogenomes revealed high structural variability. Overall, 585 RNA editing sites in protein coding genes were identified based on RNA-seq data. Among them, mttB was the most frequently edited (52 times), followed by ccmB (46 times). A phylogenetic analysis based on the S. muricatum mitogenome and those of 39 other taxa (including 25 Solanaceae species) revealed the evolutionary and taxonomic status of S. muricatum. CONCLUSIONS: We provide the first report of the assembled and annotated S. muricatum mitogenome. This information will help to lay the groundwork for future research on the evolutionary biology of Solanaceae species. Furthermore, the results will assist the development of molecular breeding strategies for S. muricatum based on the most beneficial agronomic traits of this species.


Assuntos
Genoma Mitocondrial , Filogenia , Edição de RNA , Solanum , Solanum/genética , Genoma de Planta
18.
Plant Physiol Biochem ; 211: 108718, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38733939

RESUMO

Plant secondary metabolites (PSMs) are a large class of structurally diverse molecules, mainly consisting of terpenoids, phenolic compounds, and nitrogen-containing compounds, which play active roles in plant development and stress responses. The biosynthetic processes of PSMs are governed by a sophisticated regulatory network at multiple levels. Noncoding RNAs (ncRNAs) such as microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs) may serve as post-transcriptional regulators for plant secondary metabolism through acting on genes encoding either transcription factors or participating enzymes in relevant metabolic pathways. High-throughput sequencing technologies have facilitated the large-scale identifications of ncRNAs potentially involved in plant secondary metabolism in model plant species as well as certain species with enriched production of specific types of PSMs. Moreover, a series of miRNA-target modules have been functionally characterized to be responsible for regulating PSM biosynthesis and accumulation in plants under abiotic or biotic stresses. In this review, we will provide an overview of current findings on the ncRNA-mediated regulation of plant secondary metabolism with special attention to its participation in plant stress responses, and discuss possible issues to be addressed in future fundamental research and breeding practice.


Assuntos
Plantas , RNA de Plantas , RNA não Traduzido , Metabolismo Secundário , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Metabolismo Secundário/genética , Plantas/metabolismo , Plantas/genética , RNA de Plantas/genética , RNA de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , MicroRNAs/genética , MicroRNAs/metabolismo
19.
Sensors (Basel) ; 24(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38793940

RESUMO

Mobile visible light communication (VLC) is key for integrating lighting and communication applications in the 6G era, yet there exists a notable gap in experimental research on mobile VLC. In this study, we introduce a mobile VLC system and investigate the impact of mobility speed on communication performance. Leveraging a laser-based light transmitter with a wide coverage, we enable a light fidelity (LiFi) system with a mobile receiving end. The system is capable of supporting distances from 1 m to 4 m without a lens and could maintain a transmission rate of 500 Mbps. The transmission is stable at distances of 1 m and 2 m, but an increase in distance and speed introduces interference to the system, leading to a rise in the Bit Error Rate (BER). The mobile VLC experimental system provides a viable solution to the issue of mobile access in the integration of lighting and communication applications, establishing a solid practical foundation for future research.

20.
Sci Rep ; 14(1): 11368, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762528

RESUMO

High-speed GaN-based lasers play a pivotal role in visible light communication (VLC) systems; however, the causes of the limited modulation response of our fabricated laser diode (LD) are not fully understood. Accordingly, we constructed an equivalent circuit model for both the LD and its packaging. This model enabled us to analyze the series resistance and parallel capacitance of the LD at different injection currents. Experiments and simulations were performed to investigate the intrinsic responses of the LD. The series resistance and parallel capacitance are responsible for S21 roll-off at low frequencies. Determination of the packaging design parameters on the modulation response of a transistor outline (TO)-can packaged LD was investigated which is important to achieve the impedance match in the future. The value of each discrete component was determined by fitting the scattering parameters of the equivalent circuit model to the packaged LD. Reducing the series resistance and parallel capacitance improved the modulation response. Our study firstly illustrates the design and manufacture of violet-blue-green laser transmitters with a large modulation bandwidth for ultra-high-speed VLC from the point of the impedance influence.

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