Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Heliyon ; 10(9): e30408, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38726146

RESUMO

Background: Low-dose colchicine has been shown to lower major adverse cardiovascular events (MACE) among those with cardiovascular disease (CVD). It remains unclear how long a CVD patient needs to live to potentially benefit from colchicine. Our study aimed to determine the time to benefit (TTB) of colchicine in individuals with CVD. Methods: Literature searches were performed in PubMed for the cardiovascular outcome trial of colchicine in patients with CVD until October 12, 2023. The primary outcome measured was MACE. Reconstructed individual participant data (IPD) and the stratified Cox proportional hazards model were used to calculate the hazard ratio (HR) and 95 % confidence interval (CI) to estimate the efficacy of colchicine, and Weibull survival curves were fitted to estimate TTB for specific absolute risk reduction (ARR) thresholds (0.002, 0.005, and 0.01). Results: Four trials randomizing 11,594 adults aged between 59.8 and 66.5 years were included (follow-up duration: 12-28.6 months). Compared with placebo, colchicine reduced the risk of MACE (HR 0.68, 95 % CI: 0.60 to 0.78) but had no impact on cardiovascular and all-cause mortality. A TTB of 11.0 months (95 % CI: 0.59 to 21.3) was estimated to be needed to prevent 1 MACE in 100-colchicine-treated patients. The TTB for acute coronary syndrome was similar compared to stable coronary artery disease (10.7 vs. 11.2 months for ARR = 0.010). Conclusions: By using reconstructed IPD, this pooled analysis demonstrated that colchicine was associated with reduced nonfatal MACE, and the TTB was approximately 11.0 months to prevent 1 MACE per 100 patients.

2.
Materials (Basel) ; 17(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38612208

RESUMO

The microstructures and mechanical properties of equiatomic CoCrFeMnNi high-entropy alloys (HEAs) treated with various processing parameters of laser surface heat treatment are studied in this paper. The typical inverse gradient-grained structure, which is composed of a hard central layer and a soft surface layer, can be obtained by laser surface heat treatment. A much narrower gradient layer leads to the highest yield strength by sacrificing ductility when the surface temperature of the laser-irradiated region remains at ~850 °C, whereas the fully recrystallized microstructure, which exists from the top surface layer to the ~1.05 mm depth layer, increases the ductility but decreases the yield strength as the maximum heating temperature rises to ~1050 °C. Significantly, the superior strength-ductility combination can be acquired by controlling the surface temperature of a laser-irradiated surface at ~1000 °C with a scanning speed of ~4 mm/s due to the effect of hetero-deformation-induced strengthening and hardening, as well as the enhanced interaction between dislocation and nanotwins by the hierarchical nanotwins. Therefore, retaining the partial recrystallized microstructure with a relatively high microhardness in the central layer, promoting the generation of hierarchical nanotwins, and increasing the volume proportion of gradient layer can effectively facilitate the inverse gradient-grained CoCrFeMnNi HEAs to exhibit a desirable strength-ductility synergy.

3.
Dev Comp Immunol ; 146: 104737, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37236330

RESUMO

Melanization is a component of the humoral immune defense of insects and is induced by serine protease-mediated phenoloxidase (PO) catalysis. Prophenoloxidase (PPO) in the midgut of Plutella xylostella is activated by the CLIP domain serine protease (clip-SP) in response to Bacillus thuringiensis (Bt) infection, but the detailed signaling cascade following this activation is unknown. Here, we report that activation of clip-SP enhances PO activity in the P. xylostella midgut by cleaving three downstream PPO-activating proteases (PAPs). First, the expression level of clip-SP1 was increased in the midgut after Bt8010 infection of P. xylostella. Then, purified recombinant clip-SP1 was able to activate three PAPs - PAPa, PAPb and PAP3 - which in turn enhanced their PO activity in the hemolymph. Furthermore, clip-SP1 showed a dominant effect on PO activity compared to the individual PAPs. Our results indicate that Bt infection induces the expression of clip-SP1, which is upstream of a signaling cascade, to efficiently activate PO catalysis and mediate melanization in the midgut of P. xylostella. And it provides a basis for studying the complex PPO regulatory system in the midgut during Bt infection.


Assuntos
Lepidópteros , Serina Endopeptidases , Animais , Larva , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Serina Proteases/genética , Serina Proteases/metabolismo , Precursores Enzimáticos/metabolismo , Monofenol Mono-Oxigenase , Proteínas de Insetos/metabolismo
4.
Int J Biol Macromol ; 242(Pt 1): 124678, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37141972

RESUMO

Plutella xylostella has evolved resistance to Bacillus thuringiensis Cry1Ac toxin over a long evolutionary period. Enhanced immune response is an important factor in insect resistance to a variety of insecticides, and whether phenoloxidase (PO), an immune protein, is involved in resistance to Cry1Ac toxin in P. xylostella remains unclear. Here, spatial and temporal expression patterns showed that prophenoloxidase (PxPPO1 and PxPPO2) in the Cry1S1000-resistant strain was more highly expressed in eggs, 4th instar, head, and hemolymph than those in G88-susceptible strain. The results of PO activity analysis showed that after treatment with Cry1Ac toxin PO activity was about 3 times higher than that before treatment. Furthermore, knockout of PxPPO1 and PxPPO2 significantly increased the susceptibility to Cry1Ac toxin. These findings were further supported by the knockdown of Clip-SPH2, a negative regulator of PO, which resulted in increased PxPPO1 and PxPPO2 expression and Cry1Ac susceptibility in the Cry1S1000-resistant strain. Finally, the synergistic effect of quercetin showed that larval survival decreased from 100 % to <20 % compared to the control group. This study will provide a theoretical basis for the analysis of immune-related genes (PO) genes involved in the resistance mechanism and pest control of P. xylostella.


Assuntos
Bacillus thuringiensis , Mariposas , Animais , Bacillus thuringiensis/genética , Mariposas/metabolismo , Endotoxinas/metabolismo , Toxinas de Bacillus thuringiensis/metabolismo , Larva , Monofenol Mono-Oxigenase/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Proteínas Hemolisinas/metabolismo , Proteínas de Bactérias/metabolismo
5.
Toxins (Basel) ; 15(4)2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-37104211

RESUMO

Many insects, including the Plutella xylostella (L.), have developed varying degrees of resistance to many insecticides, including Bacillus thuringiensis (Bt) toxins, the bioinsecticides derived from Bt. The polycalin protein is one of the potential receptors for Bt toxins, and previous studies have confirmed that the Cry1Ac toxin can bind to the polycalin protein of P. xylostella, but whether polycalin is associated with the resistance of Bt toxins remains controversial. In this study, we compared the midgut of larvae from Cry1Ac-susceptible and -resistant strains, and found that the expression of the Pxpolycalin gene was largely reduced in the midgut of the resistant strains. Moreover, the spatial and temporal expression patterns of Pxpolycalin showed that it was mainly expressed in the larval stage and midgut tissue. However, genetic linkage experiments showed that the Pxpolycalin gene and its transcript level were not linked to Cry1Ac resistance, whereas both the PxABCC2 gene and its transcript levels were linked to Cry1Ac resistance. The larvae fed on a diet containing the Cry1Ac toxin showed no significant change in the expression of the Pxpolycalin gene in a short term. Furthermore, the knockout of polycalin and ATP-binding cassette transporter subfamily C2 (ABCC2) genes separately by CRISPR/Cas9 technology resulted in resistance to decreased susceptibility to Cry1Ac toxin. Our results provide new insights into the potential role of polycalin and ABCC2 proteins in Cry1Ac resistance and the mechanism underlying the resistance of insects to Bt toxins.


Assuntos
Bacillus thuringiensis , Mariposas , Animais , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis/metabolismo , Sistemas CRISPR-Cas , Endotoxinas/genética , Endotoxinas/farmacologia , Endotoxinas/metabolismo , Larva , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Proteínas Hemolisinas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Proteínas de Bactérias/metabolismo , Resistência a Inseticidas/genética , Proteínas de Insetos/metabolismo
6.
Int J Biol Macromol ; 194: 74-83, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34861270

RESUMO

The rapid development of insecticide resistance has hampered the use of Bacillus thuringiensis (Bt), a widely used bio-pesticide. Plutella xylostella (L.) is a globally distributed lepidopteran pest of cruciferous vegetables and has developed severe field resistance to the Bt toxin. Vacuolar H+-ATPases (VHA) are multi-subunit complexes and participate in multiple physiological processes. However, the characterization and functional studies of VHA genes are lacking in insects. This study performed a genome-wide analysis and identified 35 VHA gene family members divided into 15 subfamilies in P. xylostella. We cloned a V-ATPase subunit G gene, PxVHA-G1, in our previous midgut transcriptome profiles. Quantitative reverse transcriptase-polymerase chain reaction results showed that PxVHA-G1 was upregulated in the Cry1S1000-resistant strain than in the G88-susceptible strain, and its expression profile revealed that the midgut, Malpighian tubules, and larva stages generally showed high expression levels. RNAi-mediated knockdown of the PxVHA-G1 gene increased the susceptibility of P. xylostella (G88 and Cry1S1000) to Cry1Ac toxin. Our study is the first to explore the role of PxVHA-G1 on regulating Cry1Ac toxicity in P. xylostella, thus, providing new insights into the role of VHAs in the development of Cry1Ac resistance and sustainable development of pest management.


Assuntos
Toxinas de Bacillus thuringiensis/metabolismo , Bacillus thuringiensis/fisiologia , Resistência à Doença , Endotoxinas/metabolismo , Estudo de Associação Genômica Ampla , Proteínas Hemolisinas/metabolismo , Interações Hospedeiro-Patógeno , Mariposas/genética , ATPases Vacuolares Próton-Translocadoras/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Toxinas de Bacillus thuringiensis/química , Clonagem Molecular , Resistência à Doença/genética , Endotoxinas/química , Proteínas Hemolisinas/química , Mariposas/classificação , Mariposas/enzimologia , Filogenia , ATPases Vacuolares Próton-Translocadoras/metabolismo
7.
Insects ; 12(12)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34940179

RESUMO

The diamondback moth, Plutella xylostella, is a lepidopteran insect that mainly harms cruciferous vegetables, with strong resistance to a variety of agrochemicals, including Bacillus thuringiensis (Bt) toxins. This study intended to screen genes associated with Bt resistance in P. xylostella by comparing the midgut transcriptome of Cry1Ac-susceptible and -resistant strains together with two toxin-treated strains 24 h before sampling. A total of 12 samples were analyzed by BGISEQ-500, and each sample obtained an average of 6.35 Gb data. Additionally, 3284 differentially expressed genes (DEGs) were identified in susceptible and resistant strains. Among them, five DEGs for cadherin, 14 for aminopeptidase, zero for alkaline phosphatase, 14 for ATP binding cassette transport, and five heat shock proteins were potentially involved in resistance to Cry1Ac in P. xylostella. Furthermore, DEGs associated with "binding", "catalytic activity", "cellular process", "metabolic process", and "cellular anatomical entity" were more likely to be responsible for resistance to Bt toxin. Thus, together with other omics data, our results will offer prospective genes for the development of Bt resistance, thereby providing a brand new reference for revealing the resistance mechanism to Bt of P. xylostella.

8.
Brain Behav ; 10(8): e01731, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32639688

RESUMO

BACKGROUND: Cognitive impairment often arises in patients suffered from stroke. Acupuncture is a recommended treatment option for stroke by the World Health Organization (WHO) and has been shown to improve the cognitive function of patients with poststroke cognitive impairment (PSCI). METHODS: In the present study, we assessed the efficacy of scalp acupuncture with cluster needling on PSCI patients. Fifty six PSCI patients were randomly separated into the reference group who received drug treatment only and the treatment group who received cluster needling of scalp acupuncture on top of drug treatment. Cognitive function was compared between the two groups before and after treatment. We also took the advantage of functional near-infrared spectroscopy to assess the cerebral hemoglobin levels. RESULTS: We reveal that applying cluster needling of scalp acupuncture on top of drug treatment can significantly improve the cognitive function and elevate the cerebral hemoglobin levels compared to patients treated with drug only. CONCLUSIONS: Our results suggest that cluster needling of scalp acupuncture is an effective treatment against PSCI and shed light on its application on other neurological disorders.


Assuntos
Terapia por Acupuntura , Disfunção Cognitiva , Acidente Vascular Cerebral , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Feminino , Humanos , Masculino , Couro Cabeludo , Espectroscopia de Luz Próxima ao Infravermelho , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Resultado do Tratamento
9.
Int J Mol Sci ; 13(1): 56-70, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22312238

RESUMO

Genistein, a major phytoestrogen of soy, is considered a potential drug for the prevention and treatment of post-menopausal osteoporosis. Mounting evidence suggested a positive correlation between genistein consumption and bone health both in vivo and in vitro. Earlier studies have revealed that genistein acted as a natural estrogen analogue which activated estrogen receptor and exerted anti-osteoporotic effect. However, it remains unclear whether PTH, the most crucial hormone that regulates mineral homeostasis, participates in the process of genistein-mediated bone protection. In the present study, we compared the therapeutic effects between genistein and nilestriol and investigated whether PTH and its specific receptor PTHR1 altered in response to genistein-containing diet in the animal model of ovariectomy. Our results showed that genistein administration significantly improved femoral mechanical properties and alleviates femoral turnover. Genistein at all doses (4.5 mg/kg, 9.0 mg/kg and 18.0 mg/kg per day, respectively) exerted improved bending strength and b-ALP limiting effects than nilestriol in the present study. However, genistein administration did not exert superior effects on bone protection than nilestriol. We also observed circulating PTH restoration in ovariectomized rats receiving genistein at the dose of 18 mg/kg per day. Meanwhile, PTHR1 abnormalities were attenuated in the presence of genistein as confirmed by RT-PCR, Western blot and immunohistochemistry. These findings strongly support the idea that besides serving as an estrogen, genistein could interact with PTH/PTHR1, causing a superior mineral restoring effect than nilestriol on certain circumstance. In conclusion, our study reported for the first time that the anti-osteoporotic effect of genistein is partly PTH/PTHR1-dependent. Genistein might be a potential option in the prevention and treatment of post-menopausal osteoporosis with good tolerance, more clinical benefits and few undesirable side effects.


Assuntos
Fêmur/efeitos dos fármacos , Genisteína/farmacologia , Hormônio Paratireóideo/metabolismo , Fitoestrógenos/farmacologia , Substâncias Protetoras/farmacologia , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo , Fosfatase Alcalina/sangue , Animais , Densidade Óssea/efeitos dos fármacos , Creatinina/sangue , Creatinina/urina , Modelos Animais de Doenças , Estriol/análogos & derivados , Estriol/química , Estriol/farmacologia , Feminino , Fêmur/fisiologia , Genisteína/química , Genisteína/uso terapêutico , Humanos , Rim/metabolismo , Rim/patologia , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/prevenção & controle , Ovariectomia , Hormônio Paratireóideo/sangue , Hormônio Paratireóideo/urina , Fitoestrógenos/química , Fitoestrógenos/uso terapêutico , Substâncias Protetoras/química , Substâncias Protetoras/uso terapêutico , Quinestrol/análogos & derivados , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Hormônio Paratireóideo/genética , Resistência à Tração
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA