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1.
Entropy (Basel) ; 26(7)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39056957

RESUMO

Metro stray currents flowing into transformer-neutral points cause the high neutral DC and a transformer to operate in the DC bias state.Because neutral DC caused by stray current varies with time, the neutral DC value cannot be used as the only characteristic indicator to evaluate the DC bias risk level. Thus, unified characteristic extraction and assessment methods are proposed to evaluate the DC bias risk of a transformer caused by stray current, considering the signals of transformer-neutral DC and vibration. In the characteristic extraction method, the primary characteristics are obtained by comparing the magnitude and frequency distributions of transformer-neutral DC and vibration with and without metro stray current invasion. By analyzing the correlation coefficients, the final characteristics are obtained by clustering the primary characteristics with high correlation. Then, the magnitude and frequency characteristics are extracted and used as indicators to evaluate the DC bias risk. Moreover, to avoid the influence of manual experience on indicator weights, the entropy weight method (EWM) is used to establish the assessment model. Finally, the proposed methods are applied based on the neutral DC and vibration test data of a certain transformer. The results show that the characteristic indicators can be extracted, and the transformer DC bias risk can be evaluated by using the proposed methods.

2.
Analyst ; 147(22): 5248, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36214231

RESUMO

Correction for 'In situ synthesis of chiral AuNCs with aggregation-induced emission using glutathione and ceria precursor nanosheets for glutathione biosensing' by Mohamed Ibrahim Halawa et al., Analyst, 2022, https://doi.org/10.1039/d2an00939k.

3.
Analyst ; 147(20): 4525-4535, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36093981

RESUMO

In the present study, a mediator release test (MRT) strategy has been designed for the photoluminescent sensing of glutathione (GSH). On the basis of the redox reaction of GSH and cerium-based nanosheets (Ce(CO3)2 NSs), Ce3+ ions were released to act as a mediator for the photoluminescence emission of the Au-thiolate complexes through an aggregation-induced emission (AIE) process. Remarkably, AIE was also accompanied by high chirality for the in situ synthesis of AuNCs using Ce(CO3)2 NSs as a template and GSH as a releaser for oligomeric Au-thiolate complexes. Multiple characterization techniques, including high-resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), selected-area electron diffraction (SAED), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), were employed to check the structure and morphology of the Ce(CO3)2 NSs as well as the successful in situ fabrication of the AuNCs. Using this new MRT strategy, an eco-friendly, selective, biocompatible and label-free AIE probe was established for the sensitive sensing of GSH with a limit of detection (LOD) of 1.02 µM. Moreover, this switch-on luminescent nanoplatform of the conjugate probe of Au-thiolate/Ce-based NSs was successfully applied for the selective and reliable GSH detection in human serum samples.


Assuntos
Cério , Glutationa , Cério/química , Glutationa/química , Ouro/química , Humanos , Limite de Detecção , Luminescência , Espectroscopia Fotoeletrônica
4.
Molecules ; 27(14)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35889337

RESUMO

Dodonaea viscosa is a medicinal plant which has been used to treat various diseases in humans. However, the anti-insect activity of extracts from D. viscosa has not been evaluated. Here, we found that the total saponins from D. viscosa (TSDV) had strong antifeedant and growth inhibition activities against 4th-instar larvae of Spodoptera litura. The median antifeeding concentration (AFC50) value of TSDV on larvae was 1621.81 µg/mL. TSDV affected the detoxification enzyme system of the larvae and also exerted antifeedant activity possibly through targeting the γ-aminobutyric acid (GABA) system. The AFC50 concentration, the carboxylesterase activity, glutathione S-transferases activity, and cytochrome P450 content increased to 258%, 205%, and 215%, respectively, and likewise the glutamate decarboxylase activity and GABA content to 195% and 230%, respectively, in larvae which fed on TSDV. However, D. viscosa saponin A (DVSA) showed better antifeedant activity and growth inhibition activity in larvae, compared to TSDV. DVSA also exerted their antifeedant activity possibly through targeting the GABA system and subsequently affected the detoxification enzyme system. Further, DVSA directly affected the medial sensillum and the lateral sensillum of the 4th-instar larvae. Stimulation of Spodoptera litura. with DVSA elicited clear, consistent, and robust excitatory responses in a single taste cell.


Assuntos
Inseticidas , Sapindaceae , Saponinas , Animais , Humanos , Larva , Saponinas/farmacologia , Sementes , Spodoptera , Ácido gama-Aminobutírico
5.
J Environ Sci Health B ; 57(1): 54-61, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34983315

RESUMO

Acetylcholinesterase (AChE) is an enzyme that catalyzes acetylcholine into choline and acetic acid. Conventional pesticides, including organophosphates and carbamates target and inhibit the activity of AChE. To obtain more pesticide precursors that meet the safety requirements, more than 200 compounds were screened. Tirotundin and parthenolide identified as potential neurotoxins to nematodes were isolated from Tithonia diversifolia and Chrysanthemum parthenium, respectively. Their IC50 values were 6.89 ± 0.30 and 5.51 ± 0.23 µg/mL, respectively against the AChE isolated from Caenorhabditis elegans. AChE was inhibited in a dose-dependent manner using the two compounds. And the Lineweaver-Burk and Dixon plots indicated that tirotundin and parthenolide were reversible inhibitors against AChE, both inhibiting AChE in a mixed-type competitive manner and demonstrating these compounds may possess dual binding site AChE inhibitors. LC50 values of tirotundin and parthenolide against C. elegans were 9.16 ± 0.21 and 7.23 ± 0.48 µg/mL, respectively. These results provide a certain theoretical basis for the development and utilization of novel pesticides.


Assuntos
Acetilcolinesterase , Praguicidas , Acetilcolinesterase/metabolismo , Animais , Caenorhabditis elegans , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Lactonas , Praguicidas/toxicidade , Sesquiterpenos , Tanacetum parthenium/metabolismo , Tithonia
6.
Anal Bioanal Chem ; 413(2): 649-659, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33155132

RESUMO

In this work, we fabricated gold nanoparticles (AuNPs) capped with both polyvinyl pyrrolidone (PVP) and iodine (I2) to act as efficient chemiluminescent coreactants for luminol. AuNPs synthesis was based on the direct chemical reduction of Au3+ with NaBH4 in the presence of PVP-I2 complex. The successful synthesis of PVP-I2@AuNPs was confirmed with scanning electron microscopy (SEM) and UV-vis spectrophotometry. Chemiluminescence (CL) intensity of luminol was greatly enhanced, upon its chemical reaction with chemisorbed I2 on AuNPs surfaces owing to the excellent catalytic activity of AuNPs. The PVP-I2@AuNPs/luminol CL sensing system was successfully applied for determination of Hg2+ ions and the results displayed linearity in a wide range from 0.5 to 2000 nM and an ultrasensitive response to 1.0 nM Hg2+. The detection limit of Hg2+ ions was 0.1 nM, which was 100 times lower than the limit value (10 nM) defined by the U.S. Environmental Protection Agency in drinkable water. This ultrasensitive luminogenic system for Hg2+ detection also exhibited excellent selectivity among 13 types of metals, suggesting that the luminol/PVP-I2@AuNPs system is a promising sensor for real-time detection of Hg2+. Graphical abstract.

7.
Pestic Biochem Physiol ; 170: 104701, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32980054

RESUMO

Fifteen flavonoids isolated from the Eupatorium adenophorum showed inhibitory activities against acetylcholinesterase (AChE) isolated from Caenorhabditis elegans and Spodoptera litura. Their IC50 values ranged from 12.54 to 89.06µg/mL and 12.08 to 86.01µg/mL, respectively against the AChE isolated from the nematode and insect species. AChE was inhibited in a dose-dependent manner by all tested flavonoids, The isolated compound quercetagetin-7-O-(6-O-caffeoyl-ß-D-glucopyranoside) displayed the highest inhibitory effect against AChE from C. elegans and S. litura, with IC50 values of 12.54 µg/mL and 12.58 µg/mL, respectively. The structure-activity relationship of flavonoids on the inhibitory activities indicated that additional phenolic hydroxyl groups in the glucose were favorable for their inhibitory effects and the degree of increase in inhibitory activity also depended on the number of phenolic hydroxyl groups. The Lineweaver-Burk and Dixon plots indicated that quercetagetin-7-O-(6-O-caffeoyl-ß-d-glucopyranoside) is a reversible inhibitor against AChE. Quercetagetin-7-O-(6-O-caffeoyl-ß-d-glucopyranoside), 5,4'-Dihydroxytlavone and quercetin-3-O-ß-d-glucopyranoside inhibited AChE in a mixed-type competitive manner and these compounds might be the dual binding site AChE inhibitors. Further, nine compounds showed poisonous effects against C. elegans and inhibitory effects on the growth and development of S. litura.


Assuntos
Acetilcolinesterase , Ageratina , Animais , Caenorhabditis elegans , Inibidores da Colinesterase/farmacologia , Flavonoides/farmacologia
8.
Rev Argent Microbiol ; 51(3): 268-277, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30670299

RESUMO

Phytophthora parasitica is an important oomycete that causes disease in a variety of plants, dimethomorph fungicides being specific for oomycetes. The aim of this study was to use RNA-seq to rapidly discover the mechanism by which dimethomorph acts in the treatment of P. parasitica. We found that the expression of 832 genes changed significantly after the dimethomorph treatment, including 365 up-regulated genes and 467 down-regulated genes. According to the Gene Ontology (GO) enrichment analysis, pathway enrichment and verification test results, the following conclusions are obtained: (i) the treatment of P. parasitica with dimethomorph causes changes in the expression levels of genes associated with the cell wall and cell wall synthesis; (ii) dimethomorph treatment results in reduced permeability of the cell membrane and changes in the expression of certain transport-related proteins; (iii) dimethomorph treatment increased reactive oxygen species and reduced the expression of genes related to the control of oxidative stress.


Assuntos
Fungicidas Industriais/farmacologia , Morfolinas/farmacologia , Phytophthora/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA-Seq , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Permeabilidade da Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/genética , Parede Celular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Estresse Oxidativo/genética , Phytophthora/genética , Doenças das Plantas/parasitologia , RNA Mensageiro/genética , Espécies Reativas de Oxigênio , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , beta-Glucanas/análise
9.
Arch Insect Biochem Physiol ; 98(2): e21451, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29399896

RESUMO

Venom is a prominently maternal virulent factor utilized by parasitoids to overcome hosts immune defense. With respect to roles of this toxic mixture involved in manipulating hosts immunity, great interest has been mostly restricted to Ichneumonoidea parasitoids associated with polydnavirus (PDV), of which venom is usually considered as a helper component to enhance the role of PDV, and limited Chalcidoidea species. In contrast, little information is available in other parasitoids, especially ectoparasitic species not carrying PDV. The ectoparasitoid Scleroderma guani injects venom into its host, Tenebrio molitor, implying its venom was involved in suppression of hosts immune response for successful parasitism. Thus, we investigated the effects of parasitism and venom of this parasitoid on counteracting the cellular immunity of its host by examining changes of hemocyte counts, and hemocyte spreading and encapsulation ability. Total hemocyte counts were elevated in parasitized and venom-injected pupae. The spreading behavior of both granulocytes and plasmatocytes was impaired by parasitization and venom. High concentration of venom led to more severely increased hemocyte counts and suppression of hemocyte spreading. The ability of hemocyte encapsulation was inhibited by venom in vitro. In addition to immediate effects observed, venom showed persistent interference in hosts cellular immunity. These results indicate that venom alone from S. guani plays a pivotal role in blocking hosts cellular immune response, serving as a regulator that guarantees the successful development of its progenies. The findings provide a foundation for further investigation of the underlying mechanisms in immune inhibitory action of S. guani venom.


Assuntos
Hemócitos/fisiologia , Interações Hospedeiro-Parasita/imunologia , Imunidade Celular/efeitos dos fármacos , Tenebrio/parasitologia , Venenos de Vespas/toxicidade , Vespas/fisiologia , Animais , Feminino , Masculino , Pupa/efeitos dos fármacos , Tenebrio/efeitos dos fármacos , Tenebrio/imunologia
10.
Sensors (Basel) ; 17(6)2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28604641

RESUMO

Remote sensing technologies have been widely applied in urban environments' monitoring, synthesis and modeling. Incorporating spatial information in perceptually coherent regions, superpixel-based approaches can effectively eliminate the "salt and pepper" phenomenon which is common in pixel-wise approaches. Compared with fixed-size windows, superpixels have adaptive sizes and shapes for different spatial structures. Moreover, superpixel-based algorithms can significantly improve computational efficiency owing to the greatly reduced number of image primitives. Hence, the superpixel algorithm, as a preprocessing technique, is more and more popularly used in remote sensing and many other fields. In this paper, we propose a superpixel segmentation algorithm called Superpixel Segmentation with Local Competition (SSLC), which utilizes a local competition mechanism to construct energy terms and label pixels. The local competition mechanism leads to energy terms locality and relativity, and thus, the proposed algorithm is less sensitive to the diversity of image content and scene layout. Consequently, SSLC could achieve consistent performance in different image regions. In addition, the Probability Density Function (PDF), which is estimated by Kernel Density Estimation (KDE) with the Gaussian kernel, is introduced to describe the color distribution of superpixels as a more sophisticated and accurate measure. To reduce computational complexity, a boundary optimization framework is introduced to only handle boundary pixels instead of the whole image. We conduct experiments to benchmark the proposed algorithm with the other state-of-the-art ones on the Berkeley Segmentation Dataset (BSD) and remote sensing images. Results demonstrate that the SSLC algorithm yields the best overall performance, while the computation time-efficiency is still competitive.

11.
J Insect Sci ; 14: 116, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25368060

RESUMO

Natural populations of Boettcherisca (Sarcophaga) peregrina Robineau-Desvoidy (Diptera: Sarcophagidae) were maintained for 20 generations and reared either on unpolluted diet or on polluted diet containing copper at a median lethal concentration (LC50) determined every five generations. This resulted in two reliable strains: the relative susceptible strain (S) and the copperresistant strain (R). The metal accumulation, growth and development, reproduction, and antioxidant enzymes were analyzed in the two strains. The results showed that compared with the S strain, the R strain showed increased metal accumulation and fecundity of female adults. Regardless of whether larvae were fed on diet with or without Cu(2+), the R strain showed higher activity of superoxide dismutase and glutathione S-transferase than the S strain, although without statistical significance. Moreover, the activity of superoxide dismutase and glutathione S-transferase increased when B. peregrina larvae were exposed to Cu(2+) at 100 µg/g but decreased when they were exposed to Cu(2+) at 800 µg/g. Larval catalase activity in the R strain was higher than in the S strain when larvae were fed on diet with or without Cu(2+), although these differences were significant only at the 100 µg/g concentration. Moreover, the activity of catalase decreased when larvae were exposed to experimental Cu(2+). Beyond all expectations, larval glutathione reductase activity was not significantly different between the two strains but changed slightly when larvae were exposed to experimental Cu(2+). These results indicate that copper resistance in B. peregrina larvae is mediated by superoxide dismutase, catalase, and glutathione S-transferase. These results also help in establishing a physiological link between antioxidase activity and the resistance level of B. peregrina to copper.


Assuntos
Catalase/metabolismo , Cobre/toxicidade , Dípteros/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Glutationa Transferase/metabolismo , Superóxido Dismutase/metabolismo , Animais , Antioxidantes/metabolismo , Cobre/metabolismo , Dieta , Dípteros/enzimologia , Resistência a Medicamentos , Feminino , Fertilidade/efeitos dos fármacos , Especificidade da Espécie
12.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 1): m20, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24526948

RESUMO

The title compound, [Bi(C4H8NOS2)2I(C12H8N2)], is monomeric, with the Bi(III) atom chelated by the two S atoms of two morpholine-4-carbodi-thio-ate ligands and the two N atoms of a 1,10-phenanthroline ligand. An iodide ligand completes the coordination sphere, with the seven-coordinate Bi(III) atom adopting a highly distorted monocapped octa-hedral geometry.

13.
Genes (Basel) ; 15(3)2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38540402

RESUMO

Fenugreek (Trigonella foenum-graecum L.) is a traditional medicinal plant for treating human diseases that is widely cultivated in many countries. However, the component and related metabolic pathways are still unclear. To understand the changes in expression of the component and related genes during seed development, this study employed metabolomic and transcriptomic analyses and integrative analysis to explore the metabolites and pathways involved in the growth of fenugreek. The antifungal activity of the fenugreek seeds was also analyzed. A total of 9499 metabolites were identified in the positive ion mode, and 8043 metabolites were identified in the negative ion mode. Among them, the main components were fatty acyls, prenol lipids, steroids, steroid derivatives, flavonoids, and isoflavonoids. Among these enriched pathways, the top 20 pathways were "flavone and flavonol biosynthesis", "isoflavonoid biosynthesis", and "flavonoid biosynthesis". 3,7-Di-O-methylquercetin, flavonoids, pseudobaptigenin, isoflavonoids, methylecgonine, alkaloids, and derivatives were the most significantly upregulated metabolites. There were 38,137 differentially expressed genes (DEGs) identified via transcriptomic analysis. According to the KEGG pathway enrichment analysis, 147 DEGs were significantly enriched in "flavonoid biosynthesis". Ten DEGs of the six key enzymes were found to be involved in three pathways related to flavonoid and alkaloid synthesis in fenugreek. The antifungal activity test revealed the inhibitory effect of the ethanol extract of fenugreek seeds on Alternaria tenuissima (Kunze)Wiltshire and Magnaporthe oryzae. These findings further prove that the use of botanical pesticides in fenugreek fruit has research value.


Assuntos
Trigonella , Humanos , Trigonella/genética , Antifúngicos/metabolismo , Extratos Vegetais/metabolismo , Flavonoides/metabolismo , Sementes/genética , Sementes/química
14.
Nat Prod Res ; : 1-6, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940256

RESUMO

A series of bis(indolyl)-hydrazide-hydrazone derivatives were synthesised, and their structures were characterised using 1H-NMR and HRMS. The antifungal activity of the prepared compounds was evaluated against Pyricularia oryzae Cav., Colletotrichum -gloeosporioides Penz., Botrytis cinerea Pers.: Fr. and Rhizoctonia solani Kühn using the mycelial growth rate method. The preliminary bioassays revealed that most of the synthesised compounds exhibited antifungal activity against the four tested fungi and displayed a remarkable inhibitory effect on the mycelium growth of R. solani. In particular, compounds 3b, 3c, and 3k demonstrated significant antifungal activity against R. solani, with EC50 values of 26.42, 20.74, and 22.41 µM, respectively, outperforming the positive control shenqinmycin (47.18 µM) and carvacrol (49.13 µM).

15.
Int J Genomics ; 2024: 8846747, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567257

RESUMO

The MC4-2 bacterium strain was isolated and purified from the Periplaneta americana intestine as a biocontrol agent with good antagonistic effect against the pathogens of a soil-borne disease called tobacco black shank. The MC4-2 strain was found to have good broad-spectrum inhibition by plate stand-off test. Based on 16S rRNA and gyrB genes, ANI analysis, and other comparative genomics methods, it was determined that the MC4-2 strain was Bacillus subtilis. The complete genome sequence showed that the genome size was 4,076,630 bp, the average GC content was 43.78%, and the total number of CDSs was 4,207. Genomic prediction analysis revealed that a total of 145 genes were annotated by the CAZy, containing mainly GH and CE enzymes that break down carbohydrates such as glucose, chitin, starch, and alginate, and a large number of enzymes involved in glycosylation were present. A total of ten secondary metabolite clusters were predicted, six clusters of which were annotated as surfactin, bacillaene, fengycin, bacillibactin, subtilosin A, and bacilysin. The present investigation found the biological control mechanism of B. subtilis MC4-2, which provides a strong theoretical basis for the best use of this strain in biological control methods and provides a reference for the subsequent development of agents of this bacterium.

16.
J Sci Food Agric ; 93(5): 1010-5, 2013 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-23400827

RESUMO

BACKGROUND: The production of watermelon in China has been seriously hampered by fruit blotch disease and limited control measures are now applied. Chitosan has been employed to control a variety of plant diseases and is considered to be the most promising biochemical to control this disease. RESULTS: The in vitro antibacterial effect of chitosan and its ability in protection of watermelon seedlings from bacterial fruit blotch were evaluated. Results showed that three types of chitosan, in particular, chitosan A at 0.40 mg mL⁻¹ significantly inhibited the growth of Acidovorax citrulli. The antibacterial activity of chitosan A was affected by chitosan concentration and incubation time. The direct antibacterial activity of chitosan may be attributed to membrane lysis evidenced by transmission electron microscopic observation. The disease index of watermelon seedlings planted in soil and the death rate of seedlings planted in perlite were significantly reduced by chitosan A at 0.40 mg mL⁻¹ compared to the pathogen control. Fresh and dry weight of watermelon seedlings planted in soil was increased by chitosan seed treatment, but not by chitosan leaf spraying. CONCLUSION: The results indicated that chitosan solution may have a potential in controlling bacterial fruit blotch of watermelon.


Assuntos
Agroquímicos/farmacologia , Antibacterianos/farmacologia , Quitosana/farmacologia , Citrullus/efeitos dos fármacos , Comamonadaceae/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Plântula/efeitos dos fármacos , Acetilação , Agroquímicos/química , Óxido de Alumínio , Antibacterianos/química , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , China , Quitosana/química , Citrullus/enzimologia , Citrullus/crescimento & desenvolvimento , Citrullus/microbiologia , Contagem de Colônia Microbiana , Comamonadaceae/crescimento & desenvolvimento , Comamonadaceae/isolamento & purificação , Comamonadaceae/ultraestrutura , Frutas/efeitos dos fármacos , Frutas/enzimologia , Frutas/crescimento & desenvolvimento , Frutas/microbiologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Peso Molecular , Concentração Osmolar , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Plântula/enzimologia , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Sementes/efeitos dos fármacos , Sementes/enzimologia , Sementes/crescimento & desenvolvimento , Sementes/microbiologia , Dióxido de Silício , Solo
17.
Front Plant Sci ; 14: 1074184, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36844064

RESUMO

Plant-derived natural products are important resources for pesticide discovery. Acetylcholinesterase (AChE) is a well-validated pesticide target, and inhibiting AChE proves fatal for insects. Recent studies have shown that the potential of various sesquiterpenoids as AChE inhibitors. However, few studies have been conducted with eudesmane-type sesquiterpenes with AChE inhibitory effects. Therefore, in this research, we isolated two new sesquiterpenes, laggeranines A (1) and B (2), along with six known eudesmane-type sesquiterpenes (3-8) from Laggera pterodonta, and characterized their structures and the inhibitory effect they exerted on AChE. The results showed that these compounds had certain inhibitory effects on AChE in a dose-dependent manner, of which compound 5 had the best inhibitory effect with IC50 of 437.33 ± 8.33 mM. As revealed by the Lineweaver-Burk and Dixon plots, compound 5 was observed to suppress AChE activity reversibly and competitively. Furthermore, all compounds exhibited certain toxicity levels on C. elegans. Meanwhile, these compounds had good ADMET properties. These results are significant for the discovery of new AChE targeting compounds, and also enrich the bioactivity activity repertoire of L. pterodonta.

18.
Cell Stress Chaperones ; 28(3): 303-320, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37071342

RESUMO

Heat shock proteins (HSP) are molecular chaperones involved in many normal cellular processes and environmental stresses. At the genome-wide level, there were no reports on the diversity and phylogeny of the heat shock protein family in Procecidochares utilis. In this study, 43 HSPs were identified from the genome of P. utilis, including 12 small heat shock proteins (sHSPs), 23 heat shock protein 40 (DNAJs), 6 heat shock protein 70 (HSP70s), and 2 heat shock protein 90 (HSP90s). The characteristics of these candidates HSP genes were analyzed by BLAST, and then phylogenetic analysis was carried out. Quantitative real-time PCR (qRT-PCR) was used to analyze the spatiotemporal expression patterns of sHSPs and HSP70s in P. utilis after temperature stress. Results showed that most sHSPs could be induced under heat stress during the adult stage of P. utilis, while a few HSP70s could be induced at the larval stage. This study provides an information framework for the HSP family of P. utilis. Moreover, it lays an important foundation for a better understanding of the role of HSP in the adaptability of P. utilis to various environments.


Assuntos
Proteínas de Choque Térmico , Chaperonas Moleculares , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Temperatura , Filogenia , Chaperonas Moleculares/genética , Proteínas de Choque Térmico HSP70/genética
19.
Front Physiol ; 14: 1248354, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795265

RESUMO

The predatory natural enemy Eocanthecona furcellata plays a crucial role in agricultural ecosystems due to its effective pest control measures and defensive venom. Predator venom contains serine protease inhibitors (SPIs), which are the primary regulators of serine protease activity and play key roles in digestion, development, innate immunity, and other physiological regulatory processes. However, the regulation mechanism of SPIs in the salivary glands of predatory natural enemies is still unknown. In this study, we sequenced the transcriptome of E. furcellata salivary gland and identified 38 SPIs genes named EfSPI1∼EfSPI38. Through gene structure, multiple sequence alignment and phylogenetic tree analysis, real-time quantitative PCR (RT-PCR) expression profiles of different developmental stages and different tissues were analyzed. RNAi technology was used to explore the gene function of EFSPI20. The results showed that these 38 EfSPIs genes contained 8 SPI domains, which were serpin, TIL, Kunitz, Kazal, Antistasin, Pacifastin, WAP and A2M. The expression profile results showed that the expression of different types of EfSPIs genes was different at different developmental stages and different tissues. Most of the EfSPIs genes were highly expressed in the egg stage. The EfSPI20, EfSPI21, EfSPI22, and EfSPI24 genes of the Pacifastin subfamily and the EfSPI35 gene of the A2M subfamily were highly expressed in the nymphal and adult stages, which was consistent with the RT-qPCR verification results. These five genes are positively correlated with each other and have a synergistic effect on E. furcellata, and they were highly expressed in salivary glands. After interfering with the expression of the EfSPI20 gene, the survival rate and predatory amount of male and female adults were significantly decreased. Taken together, we speculated some EfSPIs may inhibit trypsin, chymotrypsin, and elastase, and some EfSPIs may be involved in autoimmune responses. EfSPI20 was essential for the predation and digestion of E. furcellata, and the functions of other EfSPIs were discussed. Our findings provide valuable insights into the diversity of EfSPIs in E. furcellata and the potential functions of regulating their predation, digestion and innate immunity, which may be of great significance for developing new pest control strategies.

20.
Sci Prog ; 106(2): 368504231172613, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37198909

RESUMO

As the largest consumer of coal energy, coal-fired power plants emit large amounts of PbCl2 each year, which is of wide concern due to its high toxicity, global migration, and accumulation. Unburned carbon is considered a promising adsorbent for effective PbCl2 removal. However, there is a problem that the current unburned carbon model cannot show the structure of carbon defects on the actual unburned carbon surface. Therefore, it is important to construct defective unburned carbon models with practical significance. In addition, the adsorption mechanism of PbCl2 by an unburned model is not studied deeply enough and the reaction mechanism is not clear yet. This has seriously affected the development of effective adsorbents. To reveal the adsorption mechanism of PbCl2 on unburned carbon, the adsorption mechanism of PbCl2 on defective unburned carbon surfaces was analyzed by using the density flooding theory to investigate the adsorption process of PbCl2 on different unburned carbon models. This will provide theoretical guidance for the design and development of adsorbents for the removal of PbCl2 from coal-fired power plants.

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