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1.
Pest Manag Sci ; 80(7): 3665-3674, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38459943

RESUMO

BACKGROUND: The ladybeetle, Coccinella septempunctata, an important predator, is widely used to control aphids, whiteflies, mites, thrips, and lepidopteran pests. Diapause control technology is key to extending C. septempunctata shelf-life and commercialization. Lipid accumulation is a major feature of reproductive diapause, but the function of AKH signaling as a regulator of lipid mobilization in reproductive diapause remains unclear. This study aimed to identify and characterize AKH and AKHR genes, and clarify their functions in reproductive diapause. RESULTS: The relative expression levels of CsAKH and CsAKHR were the highest in the head and fat body, respectively, and were significantly decreased under diapause conditions, both in developmental stages and tissues (head, midgut, fat body, and ovary). Furthermore, CsAKH and CsAKHR expression was increased significantly after juvenile hormone (JH) injection, but CsMet silencing significantly inhibited CsAKH and CsAKHR expression, whereas CsMet knockdown blocked the induction effect of JH. CsAKH and CsAKHR knockdown significantly reduced water content, increased lipid storage, and promoted the expression of genes related to lipid synthesis, but significantly blocked ovarian development, and induced forkhead box O (FOXO) gene expression in C. septempunctata under reproduction conditions. By contrast, injection of AKH peptide significantly inhibited FOXO expression, reduced lipid storage, and increased water content in C. septempunctata under diapause conditions. CONCLUSION: These results indicate that CsAKH and CsAKHR are involved in the regulation of lipid accumulation and ovarian development during diapause in C. septempunctata, and provide a promising target for manipulating C. septempunctata diapause. © 2024 Society of Chemical Industry.


Assuntos
Besouros , Diapausa de Inseto , Hormônios de Inseto , Proteínas de Insetos , Oligopeptídeos , Ácido Pirrolidonocarboxílico , Reprodução , Transdução de Sinais , Animais , Hormônios de Inseto/metabolismo , Hormônios de Inseto/genética , Besouros/fisiologia , Besouros/metabolismo , Besouros/crescimento & desenvolvimento , Besouros/genética , Ácido Pirrolidonocarboxílico/análogos & derivados , Ácido Pirrolidonocarboxílico/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Oligopeptídeos/metabolismo , Feminino , Metabolismo dos Lipídeos
2.
Sci Rep ; 14(1): 5227, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38433279

RESUMO

Electrical cables, often referred to as 'blood vessels' and 'nerves' of the industry, play a vital role in the connection of electrical devices. However, traditional cables that lack distributed filtering functions are usually the primary coupling path for electromagnetic compatibility (EMC) problems. An innovative design for a filtering cable, which incorporates insulated electrical wires coated with a specific defected conductor layer (DCL), enables it to achieve distributed filtering advantages along its axis. Microwave network analysis is employed to build the two-port network model of filtering cable, which efficiently analyzes the cascading characteristics of periodic or aperiodic filtering cables. To validate, the flexible printed circuit board (FPCB) with sawtooth dumbbell-shaped DCL and mounted by capacitors is wrapped around the stripped section of the coaxial cable to manufacture a multi-stopband filtering cable. Simulated and measured results demonstrate that the proposed filtering cable can be effectively suppressed in the stopband, which can be adjusted by changing the values of capacitors.

3.
Antioxidants (Basel) ; 11(10)2022 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-36290762

RESUMO

The ultrasonic-assisted aqueous two-phase extraction (UAATPE) of flavonoid glycosides from Malvaviscus arboreous Cav. flower (MACF) was developed using ethanol/ammonia sulfate systems, followed by the ultrasonic-assisted acid hydrolysis (UAAH) of the top extract with HCl solution. The optimization of UAATPE and UAAH processes was accomplished by single-factor experiments and response surface methodology. As a result, the flavonoid glycosides enriched in the top phase could achieve a maximum yield of 35.9 ± 1.1 mg/g by UAATPE and were completely hydrolyzed by UAAH deglycosylation. The flavonoid glycosides and their hydrolyzates were separated and characterized by high-performance liquid chromatography and ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. Ultrasonic enhancement of the extraction and hydrolysis was explored by comparative study. Furthermore, the in vitro activity of the flavonoid glycosides and the aglycones were comprehensively evaluated by antioxidant activity assays, including ferric-reducing antioxidant power and scavenging DPPH, hydroxyl, and superoxide radicals. All of the IC50 values suggest that the antioxidant activity of flavonoid aglycones was stronger than that of their glucosides and even vitamin C, revealing that the deglycosylated flavonoids from MACF were the more powerful antioxidants. This study provided an effective and eco-friendly strategy for the extraction, separation, and purification of flavonoids from MACF, as well as for the development of the potential flavonoid antioxidants.

4.
J Agric Food Chem ; 66(21): 5359-5367, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29732888

RESUMO

Excess ultraviolet (UV) radiation causes numerous forms of skin damage. The aim of the present study was to assess and compare the photoprotective effects of cyanidin-3- O-glucoside (C3G) alone and encapsulated in chitosan nanoparticles (Nano-C3G) in a UVB-induced acute photodamage mouse model. Nano-C3G was developed from chitosan and sodium tripolyphosphate (TPP) by ionic gelation. The particle size, zeta potential, entrapment efficiency, drug loading, and in vitro release in 6 days were determined. Kunming (KM) mice were treated with Nano-C3G (125, 250, 500 µM) or C3G (500 µM) after part of the dorsal skin area was dehaired and then exposed to 2 J/cm2 of UVB. The nanocapsules were successfully produced and had a uniform and complete spherical shape without agglomeration. The size, zeta potential, entrapment efficiency, and drug loading of Nano-C3G was 288 nm, +30 mV, 44.90%, and 4.30%, respectively. C3G in the nanocapsules was released quite rapidly, and the release rate slowed down at higher pH. The animal experiment demonstrated that Nano-C3G could effectively reduce the UVB-induced lipid peroxidation, malondialdehyde, and 8-hydroxy-2'-deoxyguanosine contents; downregulate p53, Bcl-2-associated X (Bax), and caspase-3 and -9 expression; and balance the B-cell lymphoma-2/leukemia-2 ratio. Moreover, Nano-C3G (125, 250, 500 µM) improved the visual appearance, skin moisture, histologic appearance, and apoptotic index (based on TUNEL staining) under UVB exposure. In conclusion, these results suggest that Nano-C3G can reduce UVB-induced epidermal damage through the p53-mediated apoptosis signaling pathway. Moreover, Nano-C3G was more efficient than C3G at the same concentration (500 µM).


Assuntos
Antocianinas/administração & dosagem , Apoptose/efeitos dos fármacos , Epiderme/efeitos da radiação , Glucosídeos/administração & dosagem , Nanopartículas , Protetores contra Radiação , Raios Ultravioleta/efeitos adversos , Animais , Biomarcadores/análise , Quitosana/química , Dano ao DNA/efeitos dos fármacos , Feminino , Camundongos , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Transtornos de Fotossensibilidade/etiologia , Transtornos de Fotossensibilidade/prevenção & controle , Polifosfatos/química , Queimadura Solar , Proteína Supressora de Tumor p53/fisiologia
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