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1.
J Econ Entomol ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38894631

RESUMEN

Molting is a key solution to growth restriction in insects. The periodic synthesis and degradation of chitin, one of the major components of the insect epidermis, is necessary for insect growth. MicroRNA (miRNA) have been implicated in molting regulation, yet their involvement in the interplay interaction between the chitin synthesis pathway and 20-hydroxyecdysone signaling remains poorly understood. In this study, soluble trehalase (Tre1) and phosphoacetylglucosamine mutase (PAGM) were identified as targets of conserved miR-8-3p and miR-2a-3, respectively. The expression profiles of miR-8-3p-SfTre1 and miR-2a-3-SfPAGM exhibited an opposite pattern during the different developmental stages, indicating a negative regulatory relationship between them. This relationship was confirmed by an in vitro dual-luciferase reporter system. Overexpression of miR-8-3p and miR-2a-3 by injection of mimics inhibited the expression of their respective target genes and increased mortality, leading to death in the pre-molting, and molting death phenomena. They also caused a decrease in chitin content and expression levels of key genes in the chitin synthesis pathway (SfTre1, SfTre2, SfHK, SfG6PI, SfGFAT, SfGNA, SfPAGM, SfUAP, SfCHS1, SfCHS1a, and SfCHS1b). Conversely, the injection of miRNA inhibitors resulted in the upregulation of the expression levels of these genes. Following 20E treatment, the expression levels of miR-8-3p and miR-2a-3 decreased significantly, while their corresponding target genes increased significantly. These results indicate that miR-8-3p and miR-2a-3 play a regulatory role in the molting of Sogatella furcifera by targeting SfTre1 and SfPAGM, respectively. These findings provide new potential targets for the development of subsequent new control strategies.

2.
Int J Mol Sci ; 25(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38892266

RESUMEN

Insects have developed sophisticated detoxification systems to protect them from plant secondary metabolites while feeding on plants to obtain necessary nutrients. As an important enzyme in the system, glycosyltransferase 1 (GT1) conjugates toxic compounds to mitigate their harm to insects. However, the evolutionary link between GT1s and insect plant feeding remains elusive. In this study, we explored the evolution of GT1s across different insect orders and feeding niches using publicly available insect genomes. GT1 is widely present in insect species; however, its gene number differs among insect orders. Notably, plant-sap-feeding species have the highest GT1 gene numbers, whereas blood-feeding species display the lowest. GT1s appear to be associated with insect adaptations to different plant substrates in different orders, while the shift to non-plant feeding is related to several losses of GT1s. Most large gene numbers are likely the consequence of tandem duplications showing variations in collinearity among insect orders. These results reveal the potential relationships between the evolution of GT1s and insect adaptation to plant feeding, facilitating our understanding of the molecular mechanisms underlying insect-plant interactions.


Asunto(s)
Adaptación Fisiológica , Duplicación de Gen , Glicosiltransferasas , Insectos , Animales , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Adaptación Fisiológica/genética , Plantas/genética , Plantas/metabolismo , Evolución Molecular , Filogenia , Herbivoria , Genoma de los Insectos , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo
3.
Front Psychiatry ; 15: 1363290, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38757140

RESUMEN

Objective: To investigate the intervention effect of computerized cognitive remediation therapy (CCRT) on mental time travel (MTT) in patients with schizophrenia(SCZ). Methods: From August 2020 to July 2021, 60 patients with SCZ were randomly allocated to either the study or the control group. The control group was treated with conventional drugs alone. The study group received CCRT and medical therapy for 40 minutes three times a week for 4 weeks. The participants underwent the MTT test before and after the training. Results: A total of 28 patients in the study group and 26 patients in the control group were included in the analysis. Before training, there was no significant difference in the concretization ratio of recalling past and imagining future events between the study group and the control group (P > 0.05). After 4 weeks of training, the specific event ratio of the study group was higher than that of the control group (P < 0.01). In terms of the emotional titer of the events, the concreteness of the positive events in the study group was higher than that of the neutral events and negative events (P < 0.01). The concreteness of negative events was higher than that of neutral events (P < 0.01). Conclusion: CCRT can improve the MTT ability of SCZ patients, which is manifested by an increase in the concretiveness of recalling past and imagining future events.

5.
Pestic Biochem Physiol ; 197: 105695, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38072550

RESUMEN

Nuclear receptors play a crucial role in various signaling and metabolic pathways, such as insect molting and development. Buprofezin (2-tert-butylimino-3-isopropyl-5-phenyl-perhydro-1, 3, 5-thiadiazin-4-one), a chitin synthesis inhibitor, causes molting deformities and slow death in insects by inhibiting chitin synthesis and interfering with their metabolism. This study investigated whether buprofezin affects insect ecdysteroid signaling pathway. The treatment of buprofezin significantly suppressed the transcription levels of SfHR3 and SfHR4, two nuclear receptor genes, in third-instar nymphs of Sogatella furcifera. Meanwhile, the transcription levels of SfHR3 and SfHR4 in first-day fifth-instar nymphs were induced at 12 h after 20E treatment. In addition, the silencing of SfHR3 and SfHR4 genes in first-day fifth-instar nymphs caused severe developmental delay and molting failure, resulting in a significant reduction of survival rates at 7.36% and 2.99% on the eighth day, respectively. Further analysis showed that the silencing SfHR3 and SfHR4 significantly inhibited the transcription levels of chitin synthesis and degradation-related genes. These results indicate that buprofezin can inhibits chitin synthesis and degradation by suppressing the signal transduction of 20E through SfHR3 and SfHR4, leading to molting failure and death. This study not only expands our understanding of the molecular mechanism of buprofezin in pest control but also lays a foundation for developing new control strategies of RNAi by targeting SfHR3 and SfHR4.


Asunto(s)
Hemípteros , Muda , Animales , Muda/genética , Hemípteros/metabolismo , Insectos , Receptores Citoplasmáticos y Nucleares/metabolismo , Quitina/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo
6.
ACS Nano ; 17(21): 22095-22105, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37916602

RESUMEN

Renewable-driven electrochemical CO2 reduction reaction (CO2RR) to syngas is an encouraging alternative strategy to traditional fossil fuel-based syngas production, and the development of industrial-level electrocatalysts is vital. Herein, based on theoretical optimization of metal species, hierarchical CoxNi1-x-N-C dual single-atom catalyst (DSAC) with individual NiN4 (CO preferential) and CoN4 (H2 preferential) moieties was constructed by a two-step pyrolysis route. The Co0.5Ni0.5-N-C exhibits a stable CO Faradaic efficiency of 50 ± 5% and an industrial-level current density of 101-365 mA cm-2 in an ultrawide potential window of -0.5 to -1.1 V. The CO/H2 ratio of syngas can be conveniently tuned by regulating the Co/Ni ratio. The coupled effect of NiN4 and CoN4 moieties under a local high-pH microenvironment is responsible for the regulation of the CO/H2 selectivity and yield for the CoxNi1-x-N-C catalyst, which is not present in the mixed Co-N-C and Ni-N-C catalyst. This study provides a promising DSAC strategy for achieving industrial-level syngas production via CO2RR.

7.
Biomolecules ; 13(10)2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37892115

RESUMEN

Glutamine: fructose-6-phosphate aminotransferase (GFAT), the fourth enzyme in the chitin synthesis pathway, exerts wide-ranging effects on the growth and development of organisms. However, the role of GFAT in Sogatella furcifera remains unknown. In this study, the functional significance of the GFAT gene of S. furcifera was analyzed using a reverse transcription-polymerase chain reaction and RNA interference (RNAi) analyses. The complementary DNA sequence of SfGFAT was 3162 bp in length and contained a 2067 bp open reading frame encoding 688 amino acid residues. Structural domain analysis indicated that the SfGFAT protein consisted of one glutamine aminotransferase class 2 domain and two sugar isomerase domains. Expression profile analysis revealed that SfGFAT was expressed throughout the egg, nymph, and adult phases and was strongly expressed on the first day of each nymph stage and in the integuments of five tissues. RNAi results revealed that SfGFAT gene silencing significantly inhibited the mRNA expression of the target gene and resulted in severe mortality among S. furcifera. In summary, these findings demonstrate that SfGFAT plays a critical role in the development of S. furcifera. Moreover, these results may aid in the development of methods to control the spread of S. furcifera.


Asunto(s)
Glutamina , Hemípteros , Animales , Secuencia de Aminoácidos , Glutamina/metabolismo , Hemípteros/genética , Transaminasas/metabolismo , Crecimiento y Desarrollo
8.
Small ; 19(36): e2301992, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37127857

RESUMEN

High-performance microwave absorption (MA) materials have attracted more and more attention because they can effectively prevent microwave radiation and interference from electronic devices. Herein, a new type of MA composite is constructed by introducing carbon nanotubes (CNTs)-anchored metal-organic framework derivatives (MOFDs) into a conductive carbon nanocoil (CNC) network, denoted as CNC/CNT-MOFD. The CNC/MOFD shows a wide effective absorption band of 6.7 GHz under a filling ratio of only 9% in wax-matrix. This is attributed to the hierarchical and porous structures of MOFD bridged by the uniformly dispersed conductive CNC network and the cross-polarization induced by the 3D spiral CNCs. Besides, the as-grown 1D CNTs improve space utilization, porosity, and polarization loss of the composites, resulting in the increase of imaginary permittivity, which further realizes impedance matching and energy attenuation. The Ni nanoparticles in layers of MOFD and at the tips of CNTs generate magnetic loss, promoting the low-frequency absorption ability. Resultantly, RCS values of the optimized composite in all tested theta (θ) ranges are less than -25 dB m2 at 9.5 GHz, effectively reducing the probability of the target detected by the radar.

9.
Pestic Biochem Physiol ; 191: 105347, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36963929

RESUMEN

Dicer1 plays a vital role in the formation of mature miRNA and regulates the growth, development, and reproduction of insects. However, it remains to be clarified whether Dicer1 is involved in regulating the biological processes underlying molting and reproduction of Sogatella furcifera (Horváth). Herein, SfDicer1 expression fluctuated in all the developmental stages of S. furcifera and increased as molting progressed. SfDicer1 exhibited high expression in the integument, head, fat body, and ovary of the insects. SfDicer1 dsRNA injection into 1-day-old fourth instar nymphs of S. furcifera substantially decreased the survival rate and expression of the lethal phenotypes of wing malformation and molting defects and significantly inhibited the expression of four conserved miRNAs associated with molting development. Subsequently, following the knockdown of SfDicer1 in the newly emerged (1-12 h) females of S. furcifera, SfVg and SfVgR expression levels were decreased, thereby delaying ovarian development, decreasing the number of eggs, and considerably reducing the hatching rate compared with those of the control. Finally, after silencing SfDicer1 for 48 h, the comparative transcriptome analysis of differentially expressed genes revealed considerable enrichment of the Gene Ontology terms structural constituent of cuticle, structural molecule activity, chitin metabolic process, amino sugar metabolic process, and intracellular anatomical structure, indicating that SfDicer1 inhibition affects the transcription of genes associated with growth and development. Thus, our results suggest that SfDicer1 is essential in the molting, survival, ovarian development, and fecundity of S. furcifera and is a suitable target gene for developing an RNAi-based strategy targeting the most destructive rice insect pest.


Asunto(s)
Hemípteros , MicroARNs , Animales , Femenino , Muda/genética , Perfilación de la Expresión Génica , Hemípteros/genética , Transcriptoma , Reproducción
10.
Biomolecules ; 12(11)2022 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-36421713

RESUMEN

Trehalase (Tre) is a crucial enzyme involved in trehalose metabolism, and it plays pivotal roles in insect development and metamorphosis. However, the biological function of Tre genes in Sogatella furcifera remains unclear. In the present study, two Tre genes-SfTre1 and SfTre2-were cloned and identified based on the S. furcifera transcriptome data. Bioinformatic analysis revealed that the full-length complementary DNA of SfTre1 and SfTre2 genes were 3700 and 2757 bp long, with 1728- and 1902-bp open reading frame encoding 575 and 633 amino acid residues, respectively. Expression analysis indicated that SfTre1 and SfTre2 were expressed at all developmental stages, with the highest expression in day two adults. Furthermore, the highest expression levels of SfTre1 and SfTre2 were observed in the ovary; enriched expression was also noted in head tissues. The knockdown of SfTre1 and SfTre2 via injecting double-stranded RNAs decreased the transcription levels of the corresponding mRNAs and led to various malformed phenotypes and high lethality rates. The results of our present study indicate that SfTre1 and SfTre2 play crucial roles in S. furcifera growth and development, which can provide referable information for Tre genes as a potential target for planthopper control.


Asunto(s)
Hemípteros , Trehalasa , Femenino , Animales , Trehalasa/genética , Hemípteros/genética , Interferencia de ARN , ARN Bicatenario , Ovario
11.
Plant Dis ; 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36040221

RESUMEN

Sambucus chinensis, belonging to the Caprifoliaceae family, is an economically large herb plant that is widely cultivated in southern China for its good ornamental characteristics, edible properties, and medicinal values. In July 2021, symptoms of leaf spot were observed on Sambucus chinensis plants in two fields of Chongqing Medicinal Botanical Garden (29º8'26" N, 107º13'23" E) in Nanchuan city, Chongqing, China. Disease incidence was approximately 35 and 50% for each field. The symptoms were initially yellow or black irregular spots on leaves, and then increased to larger dark brown lesions. Finally, the entire infected leaf was blighted, withering, curl and abscission. Ten blight leaves were randomly sampled from fields. Tissues were cut into small pieces and surface sterilized with 75% ethanol for 30 s and sterilized in 2% sodium hypochlorite for 2 min, rinsed thrice with sterile distilled water, plated on potato dextrose agar (PDA) plates, and incubated at 25°C for 7 days in the dark. Later, 20 isolates were obtained from the infected leaves and had similar characteristics. Three isolates were randomly selected (CQ81, CQ82, CQ83) for the further study. Colonies on PDA were olive-green to brown with a velvety texture. Conidia (n=30) were pale- to olive-brown, smooth to verruculose and produced in long, branched chains which were easily disarticulate, single celled, and elliptical to limoniform, and measured as 2.51~4.29 × 1.63~2.14 µm. Conidiophores were solitary, straight or flexous, often unbranched. The DNA of three isolates were extracted and the internal transcribed spacer (ITS) region and translation elongation factor 1-alpha (TEF1-α) were sequenced using primer pairs ITS1/ITS4 (White et al. 1990) and EF1-728F/EF1-986R (Carbone and Kohn 1999), respectively. The sequences of three isolates were 100% identical, and one representative isolate CQ82 were deposited in GenBank (ON387641, ITS; and ON409522, TEF). BLASTn analysis of these sequences showed 99 to 100% nucleotide identity with the sequences of C. cladosporioides CPC 14705 in Korea (Bensch et al. 2010). Phylogenetic analysis using Neighbor-joining method and concatenated sequences (ITS +TEF1) with MEGA7 placed isolate CQ82 in C. cladosporioides with 99% bootstrap support. On the basis of morphological and molecular characteristics, the isolates were identified as C. cladosporioides (Bensch et al. 2010; Nam et al. 2015). A total of sixteen healthy potted plants of S. chinensis were conducted for the pathogenicity test. Eight plants were selected and one shoot of each plant was randomly used for inoculation. Leaves from the shoot of each plant were brushed with 106 conidia/ml suspension of isolate CQ82. Another 8 plants were performed in the same procedure, inoculated with sterile distilled water as control. All plants were covered with plastic bags for two days and then arranged in a greenhouse with 80% relative humidity at 25°C. The pathogenicity test was repeated thrice. After 15 days inoculation, the similar symptoms were observed on the inoculated leaves, whereas controls remained healthy. The pathogen was reisolated from blight tissue and identified as C. cladosporioides by the methods described above. Although this fungus was previously reported to cause leaf disease on many plants (Meneses et al. 2018; Sun et al. 2017), this is the first report of C. cladosporioides causing leaf blight on S. chinensis in China. This study will establish a foundation for controlling the disease.

12.
Genes (Basel) ; 13(8)2022 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-35893078

RESUMEN

UDP-N-acetylglucosamine pyrophosphorylase (UAP) is a key enzyme in the chitin biosynthesis pathway of insects. Here, we described the gene SfUAP in the white-backed planthopper Sogatella furcifera (Horváth) with an open reading frame of 1470 bp. Quantitative real-time polymerase chain reaction (qPCR) suggested that SfUAP exhibits a different developmental expression pattern and a higher expression after molting. The highest expression of SfUAP was observed in the integument tissues of adults, whereas head tissues showed negligible expression. RNAi-based gene silencing decreased the mRNA transcript levels in S. furcifera nymphs injected with double-stranded RNA of SfUAP. Finally, SfUAP silencing led to 84% mortality and malformed phenotypes in nymphs. Thus, our results can help better understand the role of SfUAP in S. furcifera.


Asunto(s)
Hemípteros , Animales , Nucleotidiltransferasas/genética , Ninfa/genética , Interferencia de ARN
13.
Insect Mol Biol ; 31(6): 798-809, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35899838

RESUMEN

Sogatella furcifera is one of the most serious insect pests that affect rice in Asia. One class of small RNAs (sRNAs; ~22 nt long) is miRNAs, which participate in various biological processes by regulating the expression of target genes in a spatiotemporal manner. However, the role of miRNAs in nymph-to-adult transition in S. furcifera remains unknown. In this study, we sequenced sRNA libraries of S. furcifera prepared from individuals at three different developmental stages (pre-moult, moulting and early adult). A total of 253 miRNAs (134 known and 119 novel) were identified, of which 12 were differentially expressed during the nymph-to-adult developmental transition. Moreover, Real time quantitative PCR (RT-qPCR) analysis revealed that all 12 miRNAs were differentially expressed among five different nymph tissues and 14 different developmental stages (first to fifth instar nymphs and 1-day-old adults). Injection of miR-2a-2 mimic/antagomir and miR-305-5p-1 mimic/antagomir into 1-day-old fifth instar nymphs significantly increased the mortality rate. In addition, a defective moulting phenotype was observed in nymphs injected with miR-2a-2 and miR-305-5p-1, suggesting that these miRNAs are involved in S. furcifera nymph-adult transition. In conclusion, these results reveal the function of critical miRNAs in S. furcifera nymph-adult transition, and also provide novel potential targets of insecticides for the long-term sustainable management of S. furcifera.


Asunto(s)
Hemípteros , Insecticidas , MicroARNs , Animales , Ninfa/genética , Antagomirs , Hemípteros/genética
14.
J Environ Manage ; 319: 115690, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35834853

RESUMEN

Due to the environmental and production problems of emulsion, it is important to efficiently separate oil-water emulsion to meet the refinery requirement and clean up oil spills. Synthesis of a universal demulsifier is not an easy task because the physical properties of crude oil vary, which makes its characterization and demulsification procedure difficult. To overcome this problem, hydrophilic and magnetically recoverable poly (methyl methacrylate-acrylic acid)/iron oxide magnetic composite nanoparticles ((P(MMA-AA)/Fe3O4 NPs) were developed as an efficient and economical demulsifier via soap-free emulsion polymerization. To characterize the magnetic composite NPs for their appropriate surface morphology and magnetic domain, TEM, FTIR, VSM, and TGA analyses were carried out. The newly synthesized NPs displayed good hydrophilic properties as they migrated quickly to the aqueous emulsion phase, which was also reassured by their water contact angle of 75°. They exhibit strong magnetic characteristics (20 amu/g) in the oil-water emulsion, makings the hydrophilic wettability capable and attractive to the external magnet. Experimental results revealed that the prepared magnetic composite NPs separated 99% of the water from stable emulsion in 30 min and could be recycled 8 times through magnetic separation. The recycled magnetic composite NPs maintain their hydrophilic wettability and efficiency in separating oil-water emulsion, making them economical and commercially viable. The migration of magnetic composite NPs to the aqueous phase in the stable emulsion with a strong magnetic domain explains the coalescence of emulsified water droplets and their quick separation from the stable emulsions through the external magnet.


Asunto(s)
Nanoestructuras , Agua , Acrilatos , Emulsiones , Compuestos Férricos , Fenómenos Magnéticos , Metacrilatos , Metilmetacrilato , Aceites , Humectabilidad
15.
Arch Insect Biochem Physiol ; 110(1): e21879, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35247285

RESUMEN

The Decapentaplegic gene controls wing patterning and spreading by regulating downstream genes in many insect species. However, the molecular characteristics, expression, and biological function of Dpp in Sogatella furcifera remain poorly understood. In this study, we cloned the Dpp gene from S. furcifera and examined its expression levels in different development stages, wing typed adults, and tissues. Then, the function of SfDpp gene was analyzed using an RNA interference (RNAi)-based approach. The results showed that the full-length complementary DNA  of the SfDpp gene consists of 1034 bp and contains a 954-bp open reading frame encoding 317 amino acids. SfDpp has a transforming growth factor-ß (TGF-ß) propeptide superfamily domain and a TGF-ß superfamily domain, typical of members of the TGF-ß superfamily. Quantitative real-time polymerase chain reaction showed that the expression of SfDpp reached its highest expression level 40 min after eclosion. RNAi-based gene silencing inhibited transcript levels of the corresponding messenger RNA in S. furcifera nymphs injected with double-stranded RNA of SfDpp and resulted in death of 29.17% and 26.67% of 4th and 5th instar nymphs, respectively. The wing deformity rate of the adults was 74.12% and 3.41% after SfDpp gene silencing in 4th and 5th instar nymphs, respectively. Examining wing development-associated genes showed that two target genes of Dpp (Vestigial and Spalt) were both dramatically downregulated after SfDpp was silenced. Our results demonstrate that downregulated SfDpp in early development causes wing expansion failure in S. furcifera. Thus, Dpp may be a target gene for restricting the migration of rice-damaging planthoppers.


Asunto(s)
Hemípteros , Animales , Hemípteros/genética , Metamorfosis Biológica , Ninfa/genética , Factor de Crecimiento Transformador beta , Alas de Animales
16.
Insects ; 13(2)2022 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-35206747

RESUMEN

The juvenile hormone (JH) is crucial for insect reproduction, and isopentenyl pyrophosphate isomerase (IPPI) is a key enzyme in the JH synthesis pathway. However, few studies have investigated how IPPI regulates insect reproduction. This study identifies and characterizes the IPPI gene (SfIPPI) from the important agricultural pest Sogatella furcifera. A phylogenetic analysis reveals a high homology of SfIPPI with the IPPI amino acid sequences of Laodelphax striatellus and Nilaparvata lugens (Stål). Furthermore, SfIPPI is expressed at various developmental stages and in various tissues of S. furcifera, and is significantly higher on the 5th day of adult emergence and in integument tissue, while lower levels are found on the 3rd day of adult emergence and in fat body and gut tissue. After silencing SfIPPI using RNA interference, the ovarian development is significantly inhibited and the fecundity is significantly reduced when compared with the control group. Additionally, SfIPPI silencing significantly decreases the expression levels of downstream JH signal transduction pathway genes (SfJHAMT, SfFAMeT, and SfKr-h1) and SfVg. Our findings are helpful in elucidating the molecular mechanism underlying the regulation of insect reproduction through genes in the JH synthesis pathway, and they provide a theoretical basis for the development of pest control treatments targeting SfIPPI.

17.
J Colloid Interface Sci ; 608(Pt 2): 1894-1906, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34752977

RESUMEN

Surface modification and composition control for nanomaterials are effective strategies for designing high-performance microwave absorbing materials (MWAMs). Herein, we have successfully fabricated Co-anchored and N-doped carbon layers on the surfaces of helical carbon nanocoils (CNCs) by wet chemical and pyrolysis methods, denoted as Co@N-Carbon/CNCs. It is found that pure CNCs show a very good microwave absorption performance under a filling ratio of only 6%, which is attributed to the uniformly dispersed conductive network and the cross polarization induced by the unique chiral and spiral morphology. The coating of N-doped carbon layers on CNCs further enriches polarization losses and the uniform anchoring of Co nanoparticles in these layers generates magnetic losses, which enhance the absorption ability and improve the low frequency performance. As compared with the pure CNCs-filling samples, the optimized Co@N-Carbon/CNCs-2.4 enhances the absorption capacity in the lower frequency range under the same thickness, and realizes the decreased thickness from 3.2 to 2.8 mm in the same X band, as well as the decreased thickness from 2.2 to 1.9 mm in the Ku band. Resultantly, a specific effective absorption wave value of 22 GHz g-1 mm-1 has been achieved, which enlightens the synthesis of ultrathin and light high-performance MWAMs.

18.
PeerJ ; 9: e11694, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34414022

RESUMEN

BACKGROUND: Accurate diagnosis of major depressive disorder (MDD) remains difficult, and one of the key challenges in diagnosing MDD is the lack of reliable diagnostic biomarkers. The objective of this study was to explore gene networks and identify potential biomarkers for MDD. METHODS: In the present study, we performed a comprehensive analysis of the mRNA expression profiles using blood samples of four patients with MDD and four controls by RNA sequencing. Differentially expressed genes (DEGs) were screened, and functional and pathway enrichment analyses were performed using the Database for Annotation, Visualization, and Integrated Discovery. All DEGs were inputted to the STRING database to build a PPI network, and the top 10 hub genes were screened using the cytoHubba plugin of the Cytoscape software. The relative expression of 10 key genes was identified by quantitative real-time polymerase chain reaction (qRT-PCR) of blood samples from 50 MDD patients and 50 controls. Plasma levels of SQSTM1 and TNFα were measured using an enzyme-linked immunosorbent assay in blood samples of 44 MDD patients and 44 controls. A sucrose preference test was used to evaluate depression-like behavior in chronic unpredictable mild stress (CUMS) model rats. Immunofluorescence assay and western blotting were performed to study the expression of proteins in the brain samples of CUMS model rats. RESULTS: We identified 247 DEGs that were closely associated with MDD. Gene ontology analyses suggested that the DEGs were mainly enriched in negative regulation of transcription by RNA polymerase II promoter, cytoplasm, and protein binding. Moreover, Kyoto Encyclopedia of Genes and Genomes pathway analysis suggested that the DEGs were significantly enriched in the MAPK signaling pathway. Ten hub genes were screened through the PPI network, and qRT-PCR assay revealed that one and six genes were downregulated and upregulated, respectively; however, SMARCA2, PPP3CB, and RAB5C were not detected. Pathway enrichment analysis for the 10 genes showed that the mTOR signaling pathway was also enriched. A strong positive correlation was observed between SQSTM1 and TNFα protein levels in patients with MDD. LC3 II and SQSTM1 protein levels were increased in the CUMS rat model; however, p-mTOR protein levels were decreased. The sucrose preference values decreased in the CUMS rat model. CONCLUSIONS: We identified 247 DEGs and constructed an MDD-specific network; thereafter, 10 hub genes were selected for further analysis. Our results provide novel insights into the pathogenesis of MDD. Moreover, SQSTM1, which is related to autophagy and inflammatory reactions, may play a key role in MDD. SQSTM1 may be used as a promising therapeutic target in MDD; additionally, more molecular mechanisms have been suggested that should be focused on in future in vivo and in vitro studies.

19.
J Insect Sci ; 21(4)2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34333649

RESUMEN

Chitin deacetylases (CDAs) are chitin-degrading enzymes that play a key role in insect molting. In this study, we identified and characterized four full-length cDNAs of CDAs from Sogatella furcifera (Horváth). Developmental expression showed that SfCDA1 and SfCDA2 were expressed at all nymph developmental stages, SfCDA3 and SfCDA4 were mainly expressed in the third-instar to fifth-instar nymph stages, whereas tissue-specific analyses indicated that four CDA genes were mainly high expressed in the integument and head during the fifth-instar nymph. RNA interference (RNAi) results revealed that SfCDA1, SfCDA2, and SfCDA4 are associated with molting defect and high mortality with nymph-adult molting. Furthermore, transcripts of chitin synthase 1 variants (SfCHS1, SfCHS1a, and SfCHS1b) were significantly downregulated and causing significant changes in the expression levels of trehalases (TRE1 and TRE2) in the SfCDA1, SfCDA2, and SfCDA4 dsRNA treatment groups. By contrast, no significant phenotypic characteristics were observed after dsSfCDA3 injection. Taken together, our results suggest that SfCDA1, SfCDA2, and SfCDA4 play a vital role in nymph-adult transition, and these genes could regulate chitin biosynthesis expression levels.


Asunto(s)
Amidohidrolasas/genética , Hemípteros , Animales , Quitina/biosíntesis , Quitina/genética , ADN Complementario , Genes de Insecto , Hemípteros/genética , Proteínas de Insectos/genética , Muda/genética , Ninfa/genética , Filogenia , Interferencia de ARN , Alas de Animales/crecimiento & desarrollo
20.
Mol Biol Rep ; 48(10): 6949-6958, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34432218

RESUMEN

Drug-induced liver injury (DILI) caused by the ingestion of medications, herbs, chemicals or dietary supplements, is a clinically widespread health problem. The underlying mechanism of DILI is the formation of reactive metabolites, which trigger mitochondrial oxidative stress and the opening of mitochondrial permeability transition (MPT) pores through direct toxicity or immune response, leading to cell inflammation, apoptosis, and necrosis. Traditionally, mitochondria play an indispensable role in maintaining the physiological and biochemical functions of cells by producing ATP and mediating intracellular signal transduction; drugs can typically stimulate the mitochondria and, in the case of sustained stress, can eventually cause impairment of mitochondrial function and metabolic activity. Meanwhile, the mitochondrial stress response, as an adaptive protective mechanism, occurs when mitochondrial homeostasis is threatened. In this review, we summarize the relevant frontier researches of the protective effects of mitochondrial stress response in DILI as well as the potential related mechanisms, thus providing some thoughts for the clinical treatment of DILI.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Mitocondrias/patología , Estrés Fisiológico , Animales , Humanos , Modelos Biológicos , Preparaciones Farmacéuticas
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