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1.
Small ; : e2405150, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39301975

RESUMO

Zeolites with band-like charge transport properties have exhibited their potential activities in sensing, optics, and electronics. Herein, a precisely designed Cu@ZSM-5 catalyst is presented with an ultra-wide bandgap of 4.27 eV, showing excellent photocatalytic activity in hydroxylation of benzene with benzene conversion 27.9% and phenol selectivity 97.6%. The SXRD and Rietveld refinement results illustrate that Cu@ZSM-5 has an average of 0.8 Cu atoms per unit cell and the single Cu atoms located in the cross-section of the sinusoidal and straight channels. XANES and EXAFS further demonstrate that the Cu atoms have an oxidation state of +2, coordinated with three OMFI-framework atoms and one ─OH group. Detailed characterizations demonstrate that the Cu@ZSM-5 with tailored bandgap is able to enhance the photoinduced electron-hole separation and hence promote selective hydroxylation of benzene to phenol via the superoxide radical route. This work may open a new way for designing electrically conductive zeolite-supported photocatalysts.

2.
Physiol Plant ; 176(5): e14538, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39344294

RESUMO

The nuclear factor Y (NF-Y) has been shown to be involved in plant growth and development in response to various environmental signals. However, the integration of these mechanisms into breeding practices for new cultivars has not been extensively investigated. In this study, the Arabidopsis gene AtNF-YB1 was introduced into rice, including inbred Kasalath and the hybrids Jinfeng × Chenghui 727 and Jinfeng × Chuanhui 907. The obtained transgenic rice showed early flowering under both natural long day (NLD) and natural short day (NSD) conditions. For the inbred Kasalath, the transgenic lines clearly showed a shorter plant height and lower grain yield, with a decrease in spike length and grain number but more productive panicles. However, the hybrids with AtNF-YB1 had much smaller or even zero reduction in spike length and grain number and more productive panicles. Thus, maintained or even increased grain yields of the transgenic hybrids were recorded under the NLD conditions. Quantitative PCR analysis indicated that the rice flowering initiation pathways were early activated via the suppression of Ghd7 induction in the transgenic rice. RNA-Seq further demonstrated that three pathways related to plant photosynthesis were markedly upregulated in both Jinfeng B and the hybrid Jinfeng × Chuanhui 907 with AtNF-YB1 expression. Moreover, physiological experiments showed an upregulation of photosynthetic rates in the transgenic lines. Taken together, this study suggests that AtNF-YB1 expression in rice not only induces early flowering but also benefits photosynthesis, which might be used to develop hybrid varieties with early ripening.


Assuntos
Flores , Regulação da Expressão Gênica de Plantas , Oryza , Plantas Geneticamente Modificadas , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/fisiologia , Oryza/metabolismo , Flores/genética , Flores/fisiologia , Flores/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fotossíntese/genética , Melhoramento Vegetal/métodos , Fator de Ligação a CCAAT/genética , Fator de Ligação a CCAAT/metabolismo
3.
Molecules ; 28(22)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38005396

RESUMO

Creating new insecticide lead compounds based on the design and modification of natural products is a novel process, of which chlorfenapyr is a typical successful example. Chlorfenapyr is an arylpyrrole derivative that has high biological activity, a wide insecticidal spectrum, and a unique mode of action. For decades, a series of chlorfenapyr derivatives were designed and synthesized continuously, of which many highly active insecticidal compounds were discovered sequentially. However, due to the widespread application of chlorfenapyr and its degradation properties, some adverse effects, including pest resistance and environmental toxicity, occurred. In this review, a brief history of the discovery and development of chlorfenapyr is first introduced. Then, the synthesis, structural modification, structure activity relationship, and action mechanism of arylpyrroles are summarized. However, challenges and limitations still exist, especially in regard to the connection with pest resistance and environmental toxicology, which is discussed at the end of this review. This comprehensive summary of chlorfenapyr further promotes its progress and sensible application for pest management.


Assuntos
Inseticidas , Piretrinas , Ecotoxicologia , Piretrinas/toxicidade , Inseticidas/farmacologia , Controle de Mosquitos
4.
Molecules ; 27(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36080487

RESUMO

Chlorfenapyr (CHL) is a type of insecticide with a wide range of insecticidal activities and unique targets. The extensive use of pesticides has caused an increase in potential risks to the environment and human health. However, the potential toxicity of CHL and its mechanisms of action on humans remain unclear. Therefore, human liver cells (HepG2) were used to investigate the cytotoxic effect and mechanism of toxicity of CHL at the cellular level. The results showed that CHL induced cellular toxicity in HepG2 cells and induced mitochondrial damage associated with reactive oxygen species (ROS) accumulation and mitochondrial calcium overload, ultimately leading to apoptosis and autophagy in HepG2 cells. Typical apoptotic changes occurred, including a decline in the mitochondrial membrane potential, the promotion of Bax/Bcl-2 expression causing the release of cyt-c into the cytosol, the activation of cas-9/-3, and the cleavage of PARP. The autophagic effects included the formation of autophagic vacuoles, accumulation of Beclin-1, transformation of LC3-II, and downregulation of p62. Additionally, DNA damage and cell cycle arrest were detected in CHL-treated cells. These results show that CHL induced cytotoxicity associated with mitochondria-mediated programmed cell death (PCD) and DNA damage in HepG2 cells.


Assuntos
Apoptose , Mitocôndrias , Autofagia , Dano ao DNA , Células Hep G2 , Humanos , Potencial da Membrana Mitocondrial , Mitocôndrias/metabolismo , Piretrinas , Espécies Reativas de Oxigênio/metabolismo
5.
Appl Microbiol Biotechnol ; 105(5): 2017-2032, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33555361

RESUMO

In the present study, the complete mitogenome of Turbinellus floccosus was sequenced, assembled, and compared with other basidiomycete mitogenomes. The mitogenome of T. floccosus consists of a circular DNA molecule, with a size of 62,846 bp. Gene arrangement analysis indicated that large-scale gene rearrangements occurred in the levels of family and genus of basidiomycete species, and the mitogenome of T. floccosus contained a unique gene order. A significant correlation between the number of introns and the mitochondrial genome size of Basidiomycota were detected (P < 0.01). A total of 896 introns were detected in the core protein-coding genes (PCGs) of 74 basidiomycete species, and the cox1 gene was the largest host gene of basidiomycete introns. Intron position class (Pcls) P383 in the cox1 gene was the most common intron in Basidiomycota, which distributed in 40 of 74 basidiomycete species. In addition, frequent intron loss/gain events were detected in basidiomycete species. More than 50% of bases around insertion sites (- 15 bp to 15 bp) of Pcls from different species were conservative, indicating site preferences of intron insertions in Basidiomycota. Further analysis showed that 76.09% of introns tended to insert downstream to a T base in Basidiomycota. Phylogenetic analysis for 74 basidiomycetes indicated mitochondrial genes are effective molecular markers for phylogeny of basidiomycetes. The study served as the first report on the mitogenome from the family Gomphaceae, which will help to understand the intron origin and evolution in Basidiomycota. KEY POINTS: • The mitogenome of Turbinellus floccosus had a unique gene arrangement. • Intron loss/gain events were detected in the 74 basidiomycete species. • Introns tend to insert downstream of a T base in basidiomycete mitogenomes.


Assuntos
Basidiomycota , Genoma Mitocondrial , Basidiomycota/genética , Rearranjo Gênico , Íntrons , Filogenia
6.
Pestic Biochem Physiol ; 171: 104735, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357557

RESUMO

Stellera chamaejasme L. is a Chinese traditional herb. It has a long history and many medicinal usages. Biflavones, one of the main active ingredients in S. chamaejasme's roots, possess excellent insecticidal activities both in vivo and in vitro. However, the mechanism of these compounds and its potential molecular targets on insect cell were still not clear. Here the whole cell patch clamp technique was used to investigate whether biflavones affects voltage-gated potassium channels (Kv) on insect neuronal cells (AW1 and WG2). The results confirmed that both the three biflavones: neochamaejasmin A (NCA), neochamaejasmin B (NCB) and isochamaejasmin A (ICM) can significantly inhibit the A-type potassium current (IA) than delayed rectifier potassium current (IK) expressed on insect cells. Moreover, ICM stood out as the strongest inhibition activity on IA with IC50 value of 106.75 µM. Multiple results suggest that the inhibition of potassium current was related to the gating modification of biflavones. ICM produced concentration dependent hyperpolarizing shifts in the voltage dependence of channel steady-state activation and inactivation. Maximal shifts of the ICM-induced V0.5, were -15.1 mV for activation and -6.93 mV for inactivation. ICM also prolonged recovery from inactivation of current. Moreover, the biflavones could inhibited AW1 cell survival in both dose- and time-dependent manners with well correlation of K+ inhibitory activity. Our study showed that biflavones from S. chamaejasme exhibiting significant blocked effects on Kv of AW1 cells and inhibited cell proliferation. These findings may not only show the toxic mechanisms of biflavones on insect cells, but also suggest that Kv channel play an important role in biflavones' mode of action and may be the new targets for designing novel insecticides.


Assuntos
Canais de Potássio de Abertura Dependente da Tensão da Membrana , Potássio , Animais , Insetos , Técnicas de Patch-Clamp , Canais de Potássio
7.
Chemistry ; 25(65): 14771-14774, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31529655

RESUMO

Cuprous oxide microcrystals with {111}, {111}/{100}, and {100} exposed facets were synthesized. 31 P MAS NMR using trimethylphosphine as the probe molecule was employed to study the acidic properties of samples. It was found that the total acidic density of samples increases evidently after sulfation compared with the pristine cuprous oxide microcrystals. During sulfation, new {100} facets are formed at the expense of {111} facets and lead to the generation of two Lewis acid sites due to the different binding states of SO4 2- on {111} and {100} facets. Moreover, DFT calculation was used to illustrate the binding models of SO4 2- on {111} and {100} facets. Also, a Pechmann condensation reaction was applied to study the acidic catalytic activity of these samples. It was found that the sulfated {111} facet has better activity due to its higher Lewis acid density compared with the sulfated {100} facet.

8.
Pestic Biochem Physiol ; 157: 169-177, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153465

RESUMO

To explore the toxicity mechanisms of neochamaejasmin A (NCA), extracted from Stellera chamaejasme L., we first evaluated its cytotoxicity on the Spodoptera frugiperda (Sf9) cell line. The results confirmed that NCA inhibited Sf9 cell survival in both a dose- and time-dependent manner. Then, intracellular biochemical assays showed that NCA induced apoptosis in Sf9 cells. Evidence of apoptosis was confirmed by morphological changes and the activation of caspases-3/9. We also observed that NCA induced apoptosis via mitochondrial-dependent intrinsic apoptotic pathway by upregulating cytochrome c and proapoptotic protein (Bax) and downregulating the mitochondrial membrane potential (MMP) and antiapoptotic protein (Bcl-2). Moreover, we found a dose-dependent increase in reactive oxygen species (ROS), accumulation of lipid peroxidation product and an inactivation of the antioxidant enzymes in treated cells. Additionally, the cleavage of PARP and G2/M arrest were also detected in Sf9 cells exposed to NCA. These findings provide critical information that NCA effectively induced apoptosis in Sf9 cells through mitochondrial pathways.


Assuntos
Biflavonoides/química , Biflavonoides/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Thymelaeaceae/química , Animais , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Células Sf9 , Transdução de Sinais/efeitos dos fármacos , Spodoptera
9.
Int J Mol Sci ; 20(20)2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31635252

RESUMO

In the present study, we assembled and compared two mitogenomes from the Rhizopogon genus. The two mitogenomes of R. salebrosus and R. vinicolor comprised circular DNA molecules, with the sizes of 66,704 bp and 77,109 bp, respectively. Comparative mitogenome analysis indicated that the length and base composition of protein coding genes (PCGs), rRNA genes and tRNA genes varied between the two species. Large fragments aligned between the mitochondrial and nuclear genomes of both R. salebrosus (43.41 kb) and R. vinicolor (12.83 kb) indicated that genetic transfer between mitochondrial and nuclear genomes has occurred over evolutionary time of Rhizopogon species. Intronic regions were found to be the main factors contributing to mitogenome expansion in R. vinicolor. Variations in the number and type of introns in the two mitogenomes indicated that frequent intron loss/gain events occurred during the evolution of Rhizopogon species. Phylogenetic analyses based on Bayesian inference (BI) and Maximum likelihood (ML) methods using a combined mitochondrial gene set yielded identical and well-supported tree topologies, wherein Rhizopogon species showed close relationships with Agaricales species. This is the first study of mitogenomes within the genus Rhizopogon, and it provides a basis for understanding the evolution and differentiation of mitogenomes from the ectomycorrhizal fungal genus.


Assuntos
Variação Genética , Genoma Mitocondrial , Genômica , Íntrons , Micorrizas/classificação , Micorrizas/genética , Filogenia , Códon , Evolução Molecular , Rearranjo Gênico , Genes Mitocondriais , Genômica/métodos , RNA de Transferência/química , RNA de Transferência/genética
10.
Molecules ; 24(3)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717097

RESUMO

Three morphology-controlled CeO2, namely nanorods (NRs), nanocubes (NCs), and nanopolyhedra (NPs), with different mainly exposed crystal facets of (110), (100), and (111), respectively, have been used as supports to prepare Ru (3 wt.%) nanoparticle-loaded catalysts. The catalysts were characterized by H2-temperature programmed reduction (H2-TPR), CO⁻ temperature programmed desorption (CO-TPD), N2 adsorption⁻desorption, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM) and energy-dispersive X-ray spectroscopy (XDS). The characterization results showed that CeO2-NRs, CeO2-NCs, and CeO2-NPs mainly expose (110), (100) and (111) facets, respectively. Moreover, CeO2-NRs and CeO2-NCs present higher oxygen vacancy concentration than CeO2-NPs. In the CO2 reforming of methane reaction, Ru/CeO2-NR and Ru/CeO2-NC catalysts showed better catalytic performance than Ru/CeO2-NPs, indicating that the catalysts with high oxygen vacancy concentration are beneficial for promoting catalytic activity.


Assuntos
Cério/química , Técnicas de Química Sintética , Metano/química , Nanopartículas/química , Rutênio/química , Adsorção , Dióxido de Carbono/química , Catálise , Hidrogênio/química , Nanopartículas/ultraestrutura , Oxirredução , Oxigênio/química
11.
Bioorg Med Chem ; 26(9): 2280-2286, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29699910

RESUMO

Novel pyrazole carboxamides with a diarylamine-modified scaffold were modified based on the bixafen (Bayer) fungicide, which has excellent activity against Rhizoctonia solani, Rhizoctonia cerealis and Sclerotinia sclerotiorum. To discover the potential insecticidal activity of these novel pyrazole carboxamides, the present study explored their possible cytoactivity on the insect neuronal cells (RP-HzVNC-AW1) in Helicoverpa zea. The preliminary bioassays showed that some of the target compounds exhibited good cytoactivity against AW1 cells. Among them, compounds a5 and b4-b7 showed good activity in vitro with IC50 values of 11.28, 10.46, 9.04, 11.72 and 12.19 µM, respectively. Notably, the IC50 value of compound b5 was better than 11.81 µM for fipronil. We subsequently attempted to illustrate the mechanism of b5. Intracellular biochemical assays showed that b5 induced AW1 cell apoptosis with a decrease in themitochondrial membrane potential, as well as a significantly increased intracellular calcium ion concentration and caspase-3 activity. A significant decrease in Bcl-2 levels and a marked augmentation of cytochrome-c and Bax were also detected. These results indicate that a mitochondrially dependent intrinsic pathway contributes to compound b5-induced apoptosis in AW1 cells. This study suggests that b5 may act as a potential insecticide that can be used for further optimization.


Assuntos
Apoptose/efeitos dos fármacos , Inseticidas/farmacologia , Lepidópteros/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Pirazóis/farmacologia , Animais , Cálcio/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Citocromos c/metabolismo , Ensaios de Triagem em Larga Escala , Proteínas de Insetos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
12.
Foods ; 13(16)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39200551

RESUMO

Plant-derived edible nanovesicles serve as crucial nanocarriers for targeted delivery of bioactive substances, including miRNAs and phytochemicals, to specific tissues. They have emerged as a significant focus in precision nutrient delivery research. In this study, Tartary-buckwheat-derived nanoparticles (TBDNs) were isolated and purified using a combination of differential centrifugation and PEG precipitation. A response surface test was employed to optimize the extraction process of TBDNs in terms of yield, total phenol and flavonoid content, as well as antioxidant activity. The results demonstrated that TBDNs exhibited the highest yield and activity at a 10% concentration of PEG, pH 5, and centrifugation temperature of 4 °C. Under these conditions, the measured yield of TBDNs was 1.7795 g/kg, with a total phenol content of 178.648 mg/100 g, total flavonoid content of 145.421 mg/100 g, and DPPH-radical-scavenging rate reaching 86.37%. Characterization through a transmission electron microscope and nanoparticle-size-tracking analyzer revealed that TBDNs possessed a teato-type vesicle structure with dispersed vesicle clusters present within them. Furthermore, the extracted TBDNs were found to have an average particle size of 182.8 nm with the main peak observed at 162.8 nm when tested for particle size distribution analysis. These findings provide a novel method for extracting TBDNs while laying the groundwork for future investigations into their activities.

13.
Front Microbiol ; 15: 1424687, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39314884

RESUMO

Introduction: Thus far, the impact of kaolin mining activities on the surrounding native plants and rhizosphere microecology has not been fully understood. Methods: In this study, we used 16S rRNA high-throughput sequencing to examine the impact of kaolin mining on the rhizosphere bacterial communities and functions of three local plant species: Conyza bonariensis, Artemisia annua, and Dodonaea viscosa. Results: The results showed that kaolin mining significantly reduced the diversity of rhizosphere bacteria in these plants, as indicated by the Shannon, Simpson, Chao1, and observed species indices (p < 0.05). Kaolin mining had an impact on the recruitment of three rhizosphere bacteria native to the area: Actinoplanes, RB41, and Mycobacterium. These bacteria were found to be more abundant in the rhizosphere soil of three local plants than in bulk soil, yet the mining of kaolin caused a decrease in their abundance (p < 0.05). Interestingly, Ralstonia was enriched in the rhizosphere of these plants found in kaolin mining areas, suggesting its resilience to environmental stress. Furthermore, the three plants had different dominant rhizosphere bacterial populations in kaolin mining areas, such as Nocardioides, Pseudarthrobacter, and Sphingomonas, likely due to the unique microecology of the plant rhizosphere. Kaolin mining activities also caused a shift in the functional diversity of rhizosphere bacteria in the three local plants, with each plant displaying different functions to cope with kaolin mining-induced stress, such as increased abundance of the GlpM family and glucan-binding domain. Discussion: This study is the first to investigate the effects of kaolin mining on the rhizosphere microecology of local plants, thus contributing to the establishment of soil microecological health monitoring indicators to better control soil pollution in kaolin mining areas.

14.
iScience ; 27(7): 110360, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39071884

RESUMO

Direct and stable conversion of CO2 to aromatics (CTA) is an attractive route for reducing CO2 emissions. However, due to the chemical inertness of CO2, direct CTA reaction with high aromatics selectivity is still challenging. In this work, a tandem catalyst Zn0.1Ti0.9Ox/HZSM-5 with appropriate density and strength of acid sites exhibits a high aromatics selectivity of 67.2% and long-term stability over 100 h. Furthermore, the total selectivity of benzene, toluene, and xylene achieves 24.1% over Zn0.1Ti0.9Ox/HZSM-5 with a modified hydrophilic surface. In addition, the CTA via the formate route has been determined in this reaction system.

15.
Foods ; 13(4)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38397590

RESUMO

The physicochemical traits of highland barley prominently affect the quality of Tsampa. To find out the relevance between the physicochemical properties of raw material and the texture parameters of processed products, twenty-five physicochemical traits and ten quality parameters for seventy-six varieties of highland barley were measured and analyzed. The results showed that there was a significant difference between the physicochemical indexes for highland barleys of various colors. The dark highland barley generally has more fat, protein, total dietary fiber, phenolic, Mg, K, Ca, and Zn and less amylose, Fe, Cu, and Mo than light colored barley. Then, these highland barleys were made into Tsampa. A comprehensive quality evaluation model based on the color and texture parameters of Tsampa was established through principal component analysis. Then, cluster analysis was used to classify the tested samples into three edible quality grades predicated on the above evaluation model. At last, the regression analysis was applied to establish a Tsampa quality predictive model according to the physicochemical traits of the raw material. The results showed that amylose, protein, ß-Glucan, and a* and b* could be used to predict the comprehensive quality of Tsampa. The predicted results indicated that 11 of 14 validated samples were consistent with the actual quality, and the accuracy was above 78.57%. Our study built the approach of the appropriate processing varieties evaluation. It may provide reference for processing specific highland barley.

16.
Foods ; 13(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38472825

RESUMO

Plant-derived exosome-like nanovesicles (PELNs) are bilayer membrane-enclosed nanovesicles secreted by plant cells, serving as carriers of various substances such as proteins, RNA, and metabolites. The mounting evidence suggests that PELN plays a crucial role in transmembrane signaling, nutrient transportation, apoptosis, and regulation of gut microbiota composition. This makes it a promising "dark nutrient" for plants to modulate human physiology and pathogenesis. A comprehensive understanding of PELN formation, uptake, and functional mechanisms can offer novel insights into plant nutrition and functional properties, thereby facilitating the precise development of plant-based foods and drugs. This article provides a summary of PELN extraction and characterization, as well as absorption and delivery processes. Furthermore, it focuses on the latest discoveries and underlying physiological mechanisms of PELN's functions while exploring future research directions.

17.
Dalton Trans ; 52(29): 10058-10063, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37417339

RESUMO

A new manganese(II)-peroxomolybdate complex, Cs4[Mn(OH2)2(Mo7O22(O2)2)]·4.25H2O (Cs-1), was isolated from an aqueous solution containing manganese(II) sulfate, sodium heptamolybdate and hydrogen peroxide by the addition of Cs+ salt. Cs-1 was characterized by single crystal X-ray diffraction, thermogravimetry (TG), IR spectroscopy, powder X-ray diffraction (PXRD), cyclic voltammetry (CV) and ultraviolet-visible spectroscopy (UV-vis). The diperoxoheptamolybdate [Mo7O22(O2)2]6- units were linked by Mn(II) ions to form a one-dimensional infinite chain of [Mn(OH2)2(Mo7O22(O2)2)]n4n-, which represents a unique structure with the coexistence of the oxidant-reductant pair O22-/Mn2+. The interconversion between [MnII(OH2)2(Mo7O22(O2)2)]4- and [MnMo9O32]6- in the aqueous solution was monitored by UV-vis spectrophotometry. It indicates that 1 is a key intermediate during the redox cycle of Mn(II) and Mn(IV) in the Mn-polyoxometalate-H2O2 system. In the oxidation process of 3,3',5,5'-tetramethylbenzidine and ortho-phenylenediamine by H2O2, Cs-1 shows notable activity as an enzyme mimetic catalyst.

18.
Insects ; 14(2)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36835673

RESUMO

During the past decades, research on insect cell culture has grown tremendously. Thousands of lines have been established from different species of insect orders, originating from several tissue sources. These cell lines have often been employed in insect science research. In particular, they have played important roles in pest management, where they have been used as tools to evaluate the activity and explore the toxic mechanisms of insecticide candidate compounds. This review intends to first briefly summarize the progression of insect cell line establishment. Then, several recent studies based on insect cell lines coupled with advanced technologies are introduced. These investigations revealed that insect cell lines can be exploited as novel models with unique advantages such as increased efficiency and reduced cost compared with traditional insecticide research. Most notably, the insect cell line-based models provide a global and in-depth perspective to study the toxicology mechanisms of insecticides. However, challenges and limitations still exist, especially in the connection between in vitro activity and in vivo effectiveness. Despite all this, recent advances have suggested that insect cell line-based models promote the progress and sensible application of insecticides, which benefits pest management.

19.
J Agric Food Chem ; 71(40): 14396-14412, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37782460

RESUMO

Obesity and related metabolic syndromes pose a serious threat to human health and quality of life. A proper diet is a safe and effective strategy to prevent and control obesity, thus maintaining overall health. However, no consensus exists on the connotations of proper diet, and it is attributed to various factors, including "nutritional dark matter" and the "matrix effect" of food. Accumulating evidence confirms that obesity is associated with the in vivo levels of miRNAs, which serve as potential markers and regulatory targets for obesity onset and progression; food-derived miRNAs can regulate host obesity by targeting the related genes or gut microbiota across the animal kingdom. Host miRNAs mediate food nutrient-gut microbiota-obesity interactions. Thus, miRNAs are important correlates of diet and obesity onset. This review outlines the recent findings on miRNA-mediated food interventions for obesity, thereby elucidating their potential applications. Overall, we provide new perspectives and views on the evaluation of dietary nutrition, which may bear important implications for dietary control and obesity prevention.


Assuntos
Microbioma Gastrointestinal , MicroRNAs , Animais , Humanos , MicroRNAs/genética , Qualidade de Vida , Obesidade/metabolismo , Dieta , Microbioma Gastrointestinal/fisiologia
20.
Nanomaterials (Basel) ; 13(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38063749

RESUMO

CuZn-based catalysts are widely used in CO2 hydrogenation, which may effectively convert CO2 to methanol and alleviate CO2 emission issues. The precise design of a model catalyst with a clear atomic structure is crucial in studying the relationship between structure and catalytic activity. In this work, a one-pot strategy was used to synthesize CuZn@ZSM-5 catalysts with approximately two Cu atoms and one Zn atom per unit cell. Atomic Cu and Zn species are confirmed to be located in the [54.6.102] and [62.104] tilings, respectively, by using magic-angle spinning nuclear magnetic resonance spectroscopy (MAS NMR), synchrotron X-ray powder diffraction (SXRD) and high-signal-to-noise-ratio annular dark field scanning transmission electron microscopy (High SNR ADF-STEM). Catalytic hydrogenation of CO2 to methanol was used as a model reaction to investigate the activity of the catalyst with confined active species. Compared to the Cu@ZSM-5, Zn@ZSM-5 and their mixture, the CuZn@ZSM-5 catalyst with a close Cu-Zn distance of 4.5 Å achieves a comparable methanol space-time yield (STY) of 92.0 mgmethanol·gcatal-1·h-1 at 533 K and 4 MPa with high stability. This method is able to confine one to three metal atoms in the zeolite channel and avoid migration and agglomeration of the atoms during the reaction, which maintains the stability of the catalyst and provides an efficient way for adjustment of the type and number of metal atoms along with the distances between them in zeolites.

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