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1.
Front Pharmacol ; 15: 1302274, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711987

RESUMO

Objective: Unsafe medication practices and medication errors are a major cause of harm in healthcare systems around the world. This study aimed to explore the factors that influence the risk of medication and provide medication risk evaluation model for adults in Shanxi province, China. Methods: The data was obtained from the provincial questionnaire from May to December 2022, relying on the random distribution of questionnaires and online questionnaires by four hospitals in Shanxi Province. Multiple linear regression analysis was used to explore the factors affecting the KAP score of residents. Univariate and multivariate logistic regression was used to determine the independent risk factors, and the nomogram was verified by receiver operating characteristic curve, calibration and decision curve analysis. Results: A total of 3,388 questionnaires were collected, including 3,272 valid questionnaires. The average scores of drugs KAP were 63.2 ± 23.04, 33.05 ± 9.60, 23.67 ± 6.75 and 33.16 ± 10.87, respectively. On the evaluation criteria of the questionnaire, knowledge was scored "fair", attitude and practice were scored "good". Sex, monthly income, place of residence, insurance status, education level, and employment were regarded as independent risk factors for medication and a nomogram was established by them. Conclusion: Males, low-income, and low-educated people are important factors affecting the risk of medication. The application of the model can help residents understand the risk of their own medication behavior and reduce the harm of medication.

2.
BMC Public Health ; 24(1): 1193, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38679720

RESUMO

BACKGROUND: Residents' adoption of preventive behaviours proved beneficial in preventing the large-scale transmission of the virus during the early stages of the COVID-19 outbreak. It is critical to investigate how social media triggers residents' preventive behaviour decisions during the COVID-19 outbreak. METHODS: This paper selected online shopping as a specific preventive behaviour for empirical investigation. An online cross-sectional survey was conducted through the Sojump website from 1 to 15 March 2020, and a total of 1,289 valid questionnaires were collected from China. This paper uses multiple regression analysis to investigate the heterogeneous impacts of different information sources on residents' online shopping willingness and online shopping behaviour and the heterogeneous impacts of different information content in social media on the transformation of residents' online shopping willingness and online shopping behaviour. RESULTS: The findings indicate that both official-media and self-media positively promote residents' online shopping willingness and behaviour, with official-media having a stronger promotional effect than self-media. Furthermore, official-media and self-media can collaboratively promote residents' online shopping willingness and online shopping behaviour. The ease-of-use and usefulness of information significantly promoted the transformation of residents' online shopping willingness. CONCLUSIONS: This study analyses the heterogeneous impacts of social media on residents' preventive behaviours from the perspectives of information source differentiation and information content differentiation, which enriches related studies and provides feasible paths for promoting residents' preventive behaviours.


Assuntos
COVID-19 , Mídias Sociais , Humanos , Mídias Sociais/estatística & dados numéricos , COVID-19/prevenção & controle , COVID-19/epidemiologia , COVID-19/psicologia , Estudos Transversais , China/epidemiologia , Masculino , Feminino , Adulto , Inquéritos e Questionários , Pessoa de Meia-Idade , Adulto Jovem , Comportamentos Relacionados com a Saúde , Comportamento do Consumidor/estatística & dados numéricos
3.
Pestic Biochem Physiol ; 201: 105863, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685216

RESUMO

The whitefly Bemisia tabaci poses a significant threat to various crops and ornamental plants and causes severe damage to the agricultural industry. Over the past few decades, B. tabaci has developed resistance to several pesticides, including imidacloprid. Therefore, elucidating the mechanism that leads to insecticide detoxification is very important for controlling B. tabaci and managing whitefly resistance to neonicotinoid insecticides. Among insect detoxification enzymes, glutathione S-transferase (GST) is an important phase II detoxification enzyme that helps detoxify exogenous toxic substances. In this study, we cloned the BtGSTz1 gene and observed that its expression level was greater in imidacloprid-resistant populations than sensitive populations of B. tabaci. By silencing BtGSTz1 via RNA interference, we found a significant increase in the mortality of imidacloprid-resistant B. tabaci. Additionally, prokaryotic expression and in vitro metabolism studies revealed that the recombinant BtGSTz1 protein could metabolize 36.36% of the total imidacloprid, providing direct evidence that BtGSTz1 plays a crucial role in the detoxification of imidacloprid. Overall, our study elucidated the role of GSTs in physiological activities related to insecticide resistance, which helps clarify the resistance mechanisms conferred by GSTs and provides useful insights for sustainable integrated pest management.


Assuntos
Glutationa Transferase , Hemípteros , Resistência a Inseticidas , Inseticidas , Neonicotinoides , Nitrocompostos , Hemípteros/efeitos dos fármacos , Hemípteros/genética , Hemípteros/metabolismo , Animais , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , Glutationa Transferase/metabolismo , Glutationa Transferase/genética , Inseticidas/farmacologia , Inseticidas/metabolismo , Resistência a Inseticidas/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Interferência de RNA , Imidazóis/farmacologia , Imidazóis/metabolismo
4.
Front Immunol ; 15: 1343512, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38533503

RESUMO

Background: Despite early attempts, the relationship between immune characteristics and gastrointestinal tract cancers remains incompletely elucidated. Hence, rigorous and further investigations in this domain hold significant clinical relevance for the development of novel potential immunotherapeutic targets. Methods: We conducted a two-sample Mendelian randomization (MR) analysis using the tools available in the "TwoSampleMR" R package. The GWAS data for these 731 immune traits were sourced from the GWAS Catalog database. Concurrently, data on gastrointestinal tract cancers, encompassing malignant tumors in the esophagus, stomach, small intestine, colon, and rectum, were extracted from the FinnGen database. The immune traits subjected to MR analysis predominantly fall into four categories: median fluorescence intensities (MFI), relative cell (RC), absolute cell (AC), and morphological parameters (MP). To ensure the reliability of our findings, sensitivity analyses were implemented to address robustness, account for heterogeneity, and alleviate the impact of horizontal pleiotropy. Results: A total of 78 immune traits causally linked to gastrointestinal tract cancers were identified, encompassing esophageal cancer (12 traits), gastric cancer (13 traits), small intestine cancer (22 traits), colon cancer (12 traits), and rectal cancer (19 traits). Additionally, 60 immune traits were recognized as protective factors associated with gastrointestinal tract cancers, distributed across esophageal cancer (14 traits), gastric cancer (16 traits), small intestine cancer (7 traits), colon cancer (14 traits), and rectal cancer (9 traits). Furthermore, it was observed that seven immune traits are causally related to gastrointestinal tract cancers in at least two locations. These traits include "CCR2 on CD14- CD16+ monocyte," "CD19 on IgD+ CD38-," "CD19 on IgD+ CD38- naive," "CD25hi CD45RA+ CD4 not Treg AC," "CD27 on unsw mem," "CD28 on CD39+ activated Treg," and "CD45 on CD4+." Conclusion: This study elucidates a causal link between immune cells and gastrointestinal tract cancers at various sites through genetic investigation. The findings of this research open up new perspectives and resources for exploring tumor prevention strategies and immunotherapeutic targets.


Assuntos
Neoplasias do Colo , Neoplasias Esofágicas , Neoplasias Gastrointestinais , Neoplasias Retais , Neoplasias Gástricas , Humanos , Análise da Randomização Mendeliana , Reprodutibilidade dos Testes
5.
J Agric Food Chem ; 72(10): 5153-5164, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38427964

RESUMO

Being a destructive pest worldwide, the whitefly Bemisia tabaci has evolved resistance to neonicotinoid insecticides. The third-generation neonicotinoid dinotefuran has commonly been applied to the control of the whitefly, but its underlying mechanism is currently unknown. On the base of our transcriptome data, here we aim to investigate whether the cytochrome P450 CYP6EM1 underlies dinotefuran resistance in the whitefly. Compared to the susceptible strain, the CYP6EM1 gene was found to be highly expressed in both laboratory and field dinotefuran-resistant populations. Upon exposure to dinotefuran, the mRNA levels of CYP6EM1 were increased. These results demonstrate the involvement of this gene in dinotefuran resistance. Loss and gain of functional studies in vivo were conducted through RNAi and transgenic Drosophila melanogaster assays, confirming the role of CYP6EM1 in conferring such resistance. In a metabolism assay in vitro, the CYP6EM1 protein could metabolize 28.11% of dinotefuran with a possible dinotefuran-dm-NNO metabolite via UPLC-QTOF/MS. Docking of dinotefuran to the CYP6EM1 protein showed a good binding affinity, with an energy of less than -6.0 kcal/mol. Overall, these results provide compelling evidence that CYP6EM1 plays a crucial role in the metabolic resistance of B. tabaci to dinotefuran. Our work provides new insights into the mechanism underlying neonicotinoid resistance and applied knowledge that can contribute to sustainable control of a global pest such as whitefly.


Assuntos
Guanidinas , Hemípteros , Inseticidas , Animais , Hemípteros/metabolismo , Drosophila melanogaster/metabolismo , Resistência a Inseticidas/genética , Neonicotinoides/metabolismo , Nitrocompostos/metabolismo , Inseticidas/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo
6.
PLoS Genet ; 20(2): e1011163, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38377137

RESUMO

Neonicotinoid insecticides, which target insect nicotinic acetylcholine receptors (nAChRs), have been widely and intensively used to control the whitefly, Bemisia tabaci, a highly damaging, globally distributed, crop pest. This has inevitably led to the emergence of populations with resistance to neonicotinoids. However, to date, there have been no reports of target-site resistance involving mutation of B. tabaci nAChR genes. Here we characterize the nAChR subunit gene family of B. tabaci and identify dual mutations (A58T&R79E) in one of these genes (BTß1) that confer resistance to multiple neonicotinoids. Transgenic D. melanogaster, where the native nAChR Dß1 was replaced with BTß1A58T&R79E, were significantly more resistant to neonicotinoids than flies where Dß1 were replaced with the wildtype BTß1 sequence, demonstrating the causal role of the mutations in resistance. The two mutations identified in this study replace two amino acids that are highly conserved in >200 insect species. Three-dimensional modelling suggests a molecular mechanism for this resistance, whereby A58T forms a hydrogen bond with the R79E side chain, which positions its negatively-charged carboxylate group to electrostatically repulse a neonicotinoid at the orthosteric site. Together these findings describe the first case of target-site resistance to neonicotinoids in B. tabaci and provide insight into the molecular determinants of neonicotinoid binding and selectivity.


Assuntos
Hemípteros , Inseticidas , Receptores Nicotínicos , Animais , Receptores Nicotínicos/genética , Inseticidas/farmacologia , Hemípteros/genética , Drosophila melanogaster , Neonicotinoides/farmacologia , Mutação
7.
Acta Pharmacol Sin ; 45(6): 1287-1304, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38360930

RESUMO

HER2-positive (HER2+) metastatic breast cancer (mBC) is highly aggressive and a major threat to human health. Despite the significant improvement in patients' prognosis given the drug development efforts during the past several decades, many clinical questions still remain to be addressed such as efficacy when combining different therapeutic modalities, best treatment sequences, interindividual variability as well as resistance and potential coping strategies. To better answer these questions, we developed a mechanistic quantitative systems pharmacology model of the pathophysiology of HER2+ mBC that was extensively calibrated and validated against multiscale data to quantitatively predict and characterize the signal transduction and preclinical tumor growth kinetics under different therapeutic interventions. Focusing on the second-line treatment for HER2+ mBC, e.g., antibody-drug conjugates (ADC), small molecule inhibitors/TKI and chemotherapy, the model accurately predicted the efficacy of various drug combinations and dosing regimens at the in vitro and in vivo levels. Sensitivity analyses and subsequent heterogeneous phenotype simulations revealed important insights into the design of new drug combinations to effectively overcome various resistance scenarios in HER2+ mBC treatments. In addition, the model predicted a better efficacy of the new TKI plus ADC combination which can potentially reduce drug dosage and toxicity, while it also shed light on the optimal treatment ordering of ADC versus TKI plus capecitabine regimens, and these findings were validated by new in vivo experiments. Our model is the first that mechanistically integrates multiple key drug modalities in HER2+ mBC research and it can serve as a high-throughput computational platform to guide future model-informed drug development and clinical translation.


Assuntos
Neoplasias da Mama , Receptor ErbB-2 , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Humanos , Feminino , Receptor ErbB-2/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Imunoconjugados/uso terapêutico , Imunoconjugados/farmacologia , Farmacologia em Rede , Modelos Biológicos , Antineoplásicos/uso terapêutico , Antineoplásicos/administração & dosagem , Camundongos , Linhagem Celular Tumoral , Metástase Neoplásica
8.
Pest Manag Sci ; 80(2): 341-354, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37688583

RESUMO

BACKGROUND: Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a major agricultural insect pest that causes severe economic losses worldwide. Several insecticides have been applied to effectively control this key pest. However, owing to the indiscriminate use of chemical insecticides, B. tabaci has developed resistance against these chemical compounds over the past several years. RESULTS: From 2019 to 2021, 23 field samples of B. tabaci were collected across China. Twenty species were identified as the Mediterranean 'Q' type (MED) and three were identified as MED/ Middle East-Asia Minor 1 mixtures. Subsequently, resistance of the selected populations to different insecticides was evaluated. The results showed that 13 populations developed low levels of resistance to abamectin. An overall upward trend in B. tabaci resistance toward spirotetramat, cyantraniliprole and pyriproxyfen was observed. In addition, resistance to thiamethoxam remained low-to-moderate in the 23 field populations. CONCLUSION: These findings suggest that the overall resistance of the field-collected B. tabaci populations has shown an upward trend over the years in China. We believe our study can provide basic data to support integrated pest management and insecticide resistance management of field B. tabaci in China. © 2023 Society of Chemical Industry.


Assuntos
Hemípteros , Inseticidas , Animais , Inseticidas/farmacologia , Resistência a Inseticidas , China , Tiametoxam
9.
Pest Manag Sci ; 80(2): 910-921, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37822143

RESUMO

BACKGROUND: Understanding the trade-offs between insecticide resistance and the associated fitness is of particular importance to sustainable pest control. One of the most devastating pest worldwide, the whitefly Bemisia tabaci, has developed resistance to various insecticides, especially the neonicotinoid group. Although neonicotinoid resistance often is conferred by P450s-mediated metabolic resistance, the relationship between such resistance and the associated fitness phenotype remains largely elusive. By gene cloning, quantitative reverse transcription (qRT)-PCR, RNA interference (RNAi), transgenic Drosophila melanogaster, metabolism capacity in vitro and 'two sex-age stage' life table study, this study aims to explore the molecular role of a P450 gene CYP4CS5 in neonicotinoid resistance and to investigate whether such resistance mechanism carries fitness costs in the whitefly. RESULTS: Our bioassay tests showed that a total of 13 field-collected populations of B. tabaci MED biotype displayed low-to-moderate resistance to thiamethoxam and clothianidin. Compared to the laboratory susceptible strain, we then found that an important P450 CYP4CS5 was remarkably upregulated in the field resistant populations. Such overexpression of CYP4CS5 had a good match with the resistance level among the whitefly samples. Further exposure to the two neonicotinoids resulted in an increase in CYP4CS5 expression. These results implicate that overexpression of CYP4CS5 is closely correlated with thiamethoxam and clothianidin resistance. RNAi knockdown of CYP4CS5 increased mortality of the resistant and susceptible populations after treatment with thiamethoxam and clothianidin in bioassay, but obtained an opposite result when using a transgenic line of D. melanogaster expressing CYP4CS5. Metabolic assays in vitro revealed that CYP4CS5 exhibited certain capacity of metabolizing thiamethoxam and clothianidin. These in vivo and in vitro assays indicate an essential role of CYP4CS5 in conferring thiamethoxam and clothianidin resistance in whitefly. Additionally, our life-table analysis demonstrate that the field resistant whitefly exhibited a prolonged development time, shortened longevity and reduced fecundity compared to the susceptible, suggesting an existing fitness cost as a result of the resistance. CONCLUSION: Collectively, in addition to the important role of CYP4CS5 in conferring thiamethoxam and clothianidin resistance, this resistance mechanism is associated with fitness costs in the whitefly. These findings not only contribute to the development of neonicotinoids resistance management strategies, but also provide a new target for sustainable whitefly control. © 2023 Society of Chemical Industry.


Assuntos
Guanidinas , Hemípteros , Inseticidas , Tiazóis , Animais , Tiametoxam/metabolismo , Drosophila melanogaster/genética , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , Oxazinas , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Inseticidas/farmacologia , Inseticidas/metabolismo , Animais Geneticamente Modificados , Resistência a Inseticidas/genética
10.
Pestic Biochem Physiol ; 196: 105635, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945266

RESUMO

The whitefly, Bemisia tabaci, comes up high metabolic resistance to most neonicotinoids in long-term evolution, which is the key problem of pest control. UGT glycosyltransferase, as a secondary detoxification enzyme, plays an indispensable role in detoxification metabolism. In this study, UGT inhibitors, 5-nitrouracil and sulfinpyrazone, dramatically augmented the toxic damage of neonicotinoids to B. tabaci. A UGT named UGT353G2 was identified in whitefly, which was notably up-regulated in resistant strain (3.92 folds), and could be induced by most neonicotinoids. Additionally, the using of RNA interference (RNAi) suppresses UGT353G2 substantially increased sensitivity to neonicotinoids in resistant strain. Our results support that UGT353G2 may be involved in the neonicotinoids resistance of whitefly. These findings will help further verify the functional role of UGTs in neonicotinoid resistance.


Assuntos
Hemípteros , Inseticidas , Animais , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Inseticidas/farmacologia , Inseticidas/metabolismo , Hemípteros/metabolismo , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , Resistência a Inseticidas/genética , Difosfato de Uridina/metabolismo
11.
In Vitro Cell Dev Biol Anim ; 59(8): 624-635, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37728854

RESUMO

PF4 is a pro-atherosclerotic molecule. Endothelial CD40, upon binding to its ligand CD40L, induces endothelial cell (EC) activation, which is a vital pathophysiological process in the initiation and progression of atherosclerosis. However, the relationship between PF4 and endothelial CD40 remains elusive. This study aims to investigate whether and how PF4 affects endothelial CD40 expression using primary HAECs. PF4 treatment down-regulated sirtuin 1 (SIRT1) expression but upregulated the expression of acetylated NF-κB p65 (Ac-p65) and CD40 in HAECs in a concentration- and time-dependent manner. Pretreatment with SIRT1 agonist (SRT1720 or RSV) or SIRT1-overexpressing lentivirus attenuated PF4-induced Ac-p65 and CD40 expression in HAECs, whereas preincubation with SIRT1 antagonist (NAM or EX527) or SIRT1 shRNA had the opposite effect. To investigate whether NF-κB/p65 signaling pathway modulates CD40 expression in PF4-treated HAECs, PDTC, a NF-κB inhibitor, and p65-shRNA were introduced. PDTC or p65-shRNA treatment down-regulated Ac-p65 expression in HAECs. PDTC or p65-shRNA preincubation suppressed CD40 expression in HAECs after PF4 treatment. To better determine whether SIRT1 regulates CD40 expression in PF4-treated HAECs via the NF-κB/p65 signaling pathway, p65-knockdown HAECs were preincubated with SIRT1 agonists before PF4 treatment. SIRT1 agonist preincubation further decreased CD40 expression in p65-knockdown HAECs treated with PF4. Moreover, PF4 treatment promoted p65 nuclear translocation in HAECs. The results of dual luciferase assay demonstrated that four NF-κB binding sites in the promoter of human CD40 gene were activated in PF4-treated HAECs. In conclusion, our findings suggest that PF4 treatment facilitates CD40 expression in HAECs through the SIRT1/NF-κB/p65 pathway.


Assuntos
NF-kappa B , Sirtuína 1 , Humanos , Animais , NF-kappa B/metabolismo , Sirtuína 1/genética , Células Endoteliais , Fator Plaquetário 4/metabolismo , Fator Plaquetário 4/farmacologia , Transdução de Sinais , RNA Interferente Pequeno/metabolismo
12.
Pestic Biochem Physiol ; 194: 105468, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532309

RESUMO

High level resistance for a variety of insecticides has emerged in Bemisia tabaci, a globally notorious insect. Neonicotinoid insecticides have been applied widely to control B. tabaci. Whether a differentially expressed gene CYP6DB3 discovered from transcriptome data of B. tabaci is involved in the resistance to neonicotinoid insecticides remains unclear. In the study, CYP6DB3 expression was significantly up-regulated in both thiamethoxam- and imidacloprid-resistant strains relative to the susceptive strains. We also found that CYP6DB3 expression was up-regulated after B. tabaci adults were exposed to thiamethoxam and imidacloprid. Moreover, knocking down CYP6DB3 expression via feeding corresponding dsRNA significantly reduced CYP6DB3 mRNA levels by 34.1%. Silencing CYP6DB3 expression increased the sensitivity of B. tabaci Q adults against both thiamethoxam and imidacloprid. Overexpression of CYP6DB3 gene reduced the toxicity of imidacloprid and thiamethoxam to transgenic D. melanogaster. In addition, metabolic studies showed that CYP6DB3 can metabolize 24.41% imidacloprid in vitro. Collectively, these results strongly support that CYP6DB3 plays an important role in the resistance of B. tabaci Q to imidacloprid and thiamethoxam. This work will facilitate a deeper insight into the part of cytochrome P450s in the evolution of insecticide resistance and provide a theoretical basis for the development of new integrated pest resistance management.


Assuntos
Hemípteros , Inseticidas , Animais , Tiametoxam/metabolismo , Inseticidas/farmacologia , Inseticidas/metabolismo , Hemípteros/genética , Hemípteros/metabolismo , Drosophila melanogaster/metabolismo , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , Resistência a Inseticidas/genética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo
13.
Pestic Biochem Physiol ; 194: 105469, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532310

RESUMO

Bemisia tabaci (Hemiptera: Gennadius) is a notorious pest that is capable of feeding on >600 kinds of agricultural crops. Imidacloprid is critical in managing pest with sucking mouthparts, such as B. tabaci. However, the field population of B. tabaci has evolved resistance because of insecticide overuse. The overexpression of the detoxification enzyme cytochrome P450 monooxygenase is considered the main mechanism of imidacloprid resistance, but the mechanism underlying gene regulation remains unclear. MicroRNAs are a type of endogenous small molecule compounds that is fundamental in regulating gene expression at the post-transcriptional level. Whether miRNAs are related to the imidacloprid resistance of B. tabaci remains unknown. To gain deep insight into imidacloprid resistance, we conducted on miRNAs expression profiling of two B. tabaci Mediterranean (MED) strains with 19-fold resistance through deep sequencing of small RNAs. A total of 8 known and 1591 novel miRNAs were identified. In addition, 16 miRNAs showed significant difference in expression levels between the two strains, as verified by quantitative reverse transcription PCR. Among these, novel_miR-376, 1517, and 1136 significantly expressed at low levels in resistant samples, decreasing by 36.9%, 60.2%, and 15.6%, respectively. Moreover, modulating novel_miR-1517 expression by feeding with 1517 inhibitor and 1517 mimic significantly affected B. tabaci imidacloprid susceptibility by regulating CYP6CM1 expression. In this article, miRNAs related to imidacloprid resistance of B. tabaci were systematically screened and identified, providing important information for the miRNA-based technological innovation for this pest management.


Assuntos
Hemípteros , Inseticidas , MicroRNAs , Animais , Hemípteros/metabolismo , Resistência a Inseticidas/genética , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Inseticidas/farmacologia , Inseticidas/metabolismo , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , MicroRNAs/genética
14.
Pest Manag Sci ; 79(10): 3883-3892, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37226658

RESUMO

BACKGROUND: Difference in physiology level between the immature and mature stages of insects likely contribute to different mechanisms of insecticide resistance. It is well acknowledged that insect 20-hydroxyecdysone (20E) plays an important role in many biological processes in the immature stage, whether 20E confers insecticide resistance at this specific stage is still poorly understood. By gene cloning, reverse transcription quantitative real-time PCR, RNA interference (RNAi) and in vitro metabolism experiments, this study aimed to investigate the potential role of 20E-related genes in conferring imidacloprid (IMD) resistance in the immature stage of the whitefly Bemisia tabaci Mediterranean. RESULTS: After identification of low to moderate IMD resistance in the whitefly, we found CYP306A1 of the six 20E-related genes was overexpressed in the nymph stage of the three resistant strains compared to a laboratory reference susceptible strain, but not in the adult stage. Further exposure to IMD resulted in an increase in CYP306A1 expression in the nymph stage. These results together imply that CYP306A1 may be implicated in IMD resistance in the nymph stage of the whitefly. RNAi knockdown of CYP306A1 increased the mortality of nymphs after treatment with IMD in bioassay, suggesting a pivotal role of CYP306A1 in conferring IMD resistance in the nymph stage. Additionally, our metabolism experiments in vivo showed that the content of IMD reduced by 20% along with cytochrome P450 reductase and heterologously expressed CYP306A1, which provides additional evidence for the important function of CYP306A1 in metabolizing IMD that leads to the resistance. CONCLUSION: This study uncovers a novel function of the 20E biosynthesis gene CYP306A1 in metabolizing imidacloprid, thus contributing to such resistance in the immature stage of the insect. These findings not only advance our understanding of 20E-mediated insecticide resistance, but also provide a new target for sustainable pest control of global insect pests such as whitefly. © 2023 Society of Chemical Industry.


Assuntos
Hemípteros , Inseticidas , Animais , Inseticidas/farmacologia , Inseticidas/metabolismo , Ninfa/genética , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Insetos , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo , Resistência a Inseticidas/genética
15.
J Econ Entomol ; 116(4): 1342-1351, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37208311

RESUMO

Cytochrome P450 monooxygenases (P450s) are well-known for their crucial roles in the detoxification of xenobiotics. However, whether CYP6CX2 and CYP6CX3, 2 genes from our Bemisia tabaci (B. tabaci) MED/Q genome data were associated with detoxification metabolism and confer resistance to thiamethoxam is unclear. In this study, we investigated the role of CYP6CX2 and CYP6CX3 in mediating whitefly thiamethoxam resistance. Our results showed that mRNA levels of CYP6CX2 and CYP6CX3 were up-regulated after exposure to thiamethoxam. Transcriptional levels of 2 genes were overexpressed in laboratory and field thiamethoxam resistant strains by RT-qPCR. These results indicate that the enhanced expression of CYP6CX2 and CYP6CX3 appears to confer thiamethoxam resistance in B. tabaci. Moreover, linear regression analysis showed that the expression levels of CYP6CX2 and CYP6CX3 were positively correlated with thiamethoxam resistance levels among populations. The susceptibility of whitefly adults was markedly increased after silencing 2 genes by RNA interference (RNAi) which further confirming their major role in thiamethoxam resistance. Our findings provide information to better understand the roles of P450s in resistance to neonicotinoids and suggest that these genes may be applied to develop target genes for sustainable management tactic of agricultural pests such as B. tabaci.


Assuntos
Hemípteros , Inseticidas , Animais , Tiametoxam/metabolismo , Hemípteros/genética , Hemípteros/metabolismo , Nitrocompostos/farmacologia , Resistência a Inseticidas/genética , Neonicotinoides , Inseticidas/farmacologia , Inseticidas/metabolismo
16.
J Agric Food Chem ; 71(19): 7221-7229, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37157975

RESUMO

The sweet potato whitefly, Bemisia tabaci, (Gennadius) (Hemiptera:Aleyrodidae) is a global pest of crops. Neonicotinoids are efficient insecticides used for control of this pest. Insecticidal targets of neonicotinoids are insect nicotinic acetylcholine receptors (nAChRs). Here, we characterized and cloned the full length of the nAChR ß1 subunit (BTß1) in B. tabaci and confirmed the consistency of BTß1 in B. tabaci MEAM1 and MED. Expression levels of BTß1 in different developmental stages and body parts of adults were investigated and compared in B. tabaci MED. dsRNA was prepared to knock down BTß1 in adult B. tabaci and significantly decreases the susceptibility to five neonicotinoid insecticides, including imidacloprid, clothianidin, thiacloprid, nitenpyram, and dinotefuran. This study indicated BTß1 as a notable site influencing the susceptibility of B. tabaci to neonicotinoids.


Assuntos
Hemípteros , Inseticidas , Receptores Nicotínicos , Animais , Inseticidas/toxicidade , Inseticidas/metabolismo , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Resistência a Inseticidas/genética , Neonicotinoides/metabolismo , Nitrocompostos/farmacologia , Nitrocompostos/metabolismo
17.
Front Psychol ; 14: 1075211, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968725

RESUMO

Introduction: This study explored the formation mechanism of consumers' self-protective behavior during the COVID-19 pandemic, which is very important for policy settings to regulate consumer behavior. Based on the basic framework of the Protective Action Decision Model (PADM), this study analyzed the formation mechanism of consumers' self-protective willingness from the perspective of risk information, and explained the deviation between consumers' self-protective willingness and behavior from the perspective of protective behavior attributes. Methods: Based on 1,265 consumer survey data during the COVID-19 pandemic, the empirical test was carried out. Results and Discussion: The amount of risk information has a significant positive impact on the consumers' self-protective willingness, where the credibility of risk information plays a positive moderating role between them. Risk perception plays a positive mediating role between the amount of risk information and the consumers' self-protective willingness, and the positive mediating effect of risk perception is negatively moderated by the credibility of risk information. In the protective behavior attributes, hazard-related attributes play a positive moderating role between the consumers' self-protective willingness and behavior, while resource-related attributes play the opposite role. Consumers pay more attention to hazard-related attributes than resource-related attributes, and they are willing to consume more resources to reduce risk.

18.
Int J Biol Macromol ; 233: 123647, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36780959

RESUMO

Cuticular proteins (CPs) play an important role in protecting insects from adverse environmental conditions, like neonicotinoid insecticides, which are heavily used for numerous pests and caused environmental problems and public health concerns worldwide. However, the relationship between CPs and insecticides resistance in Bemisia tabaci, a serious and developed high insecticide resistance, is lacking. In this study, 125 CPs genes were identified in B. tabaci. Further phylogenetic tree showed the RR-2-type genes formed large gene groups in B. tabaci. Transcriptional expression levels of CPs genes at different developmental stages revealed that some CPs genes may play a specific role in insect development. The TEM results indicated that the cuticle thickness of susceptible strain was thinner than imidacloprid-resistance strain. Furthermore, 16 CPs genes (5 in RR-1 subfamily, 7 in RR-2 subfamily, 3 in CPAP3 subfamily and 1 in CPCFC subfamily) were activated in response to imidacloprid. And RNAi results indicated that CP9 and CP83 involved in imidacloprid resistance. In conclusion, this study was the first time to establish a basic information framework and evolutionary relationship between CPs and imidacloprid resistance in B. tabaci, which provides a basis for proposing integrated pest management strategies.


Assuntos
Hemípteros , Inseticidas , Animais , Inseticidas/farmacologia , Inseticidas/metabolismo , Hemípteros/metabolismo , Filogenia , Neonicotinoides/farmacologia , Neonicotinoides/metabolismo , Nitrocompostos/farmacologia
19.
J Agric Food Chem ; 71(5): 2333-2343, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36705580

RESUMO

Bemisia tabaci has developed high resistance to many insecticides and causes substantial agricultural and economic losses annually. The insecticide resistance of whitefly has been widely reported in previous studies; however, the underlying mechanism remains little known. In this study, we cloned two P450 genes: CYP6DW3 and CYP6DW5v1; these genes were markedly overexpressed in imidacloprid-resistant whitefly populations compared with susceptible populations, and knockdown of these genes decreased the imidacloprid resistance of whitefly. Moreover, heterologous expression of whitefly P450 genes in SF9 cells and metabolic studies showed that the CYP6DW3 protein could metabolize 14.11% imidacloprid and produced imidacloprid-urea in vitro. Collectively, the expression levels of CYP6DW3 and CYP6DW5v1 are positively correlated with imidacloprid resistance in B. tabaci. Our study further reveals that cytochrome P450 enzymes affect the physiological activities related to resistance in insects, which helps scholars more deeply understand the resistance mechanism, and contributes to the development of integrated pest management framework.


Assuntos
Hemípteros , Inseticidas , Animais , Hemípteros/metabolismo , Neonicotinoides/metabolismo , Inseticidas/farmacologia , Nitrocompostos/metabolismo , Resistência a Inseticidas/genética
20.
Insect Sci ; 30(1): 173-184, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35633508

RESUMO

Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is often used for biological control of small arthropod pests in greenhouse vegetable production systems in Asia. In addition to feeding on arthropod prey, O. sauteri consumes small quantities of plant material. Previous studies demonstrated that tomato plant chemistry confers antixenosis resistance to phloem-feeding whiteflies, but the potential nontarget effects of phytochemicals on the beneficial predator O. sauteri are unknown. Comparison of O. sauteri confined to near-isogenic lines (NILs) of tomatoes producing high levels of flavonoids (NIL-purple hypocotyl; resistant to whiteflies) and low levels of flavonoids (NIL-green hypocotyl; susceptible to whiteflies) revealed that O. sauteri had reduced oviposition, nymphal survival, and development on resistant plants, even if they were also provided with prey that did not feed on the host plant. Moreover, O. sauteri showed a significant ovipositional preference in choice assays, laying significantly more eggs on susceptible than on resistant plants. Molecular gut content analysis using the specific chloroplast trnL gene from tomato confirmed that adult and immature O. sauteri feed on both resistant and susceptible genotypes, and feeding behavior assays revealed that resistance did not affect plant feeding or prey acceptance by O. sauteri adults. These results demonstrate a direct negative effect of phytochemicals on a nontarget beneficial species and indicate that resistance mediated by phytochemicals can affect organisms that do not solely feed on phloem sap. The results also indicate that the mode of action and the potential ecological effects of phytochemical-mediated resistance are broader than previously recognized.


Assuntos
Hemípteros , Heterópteros , Solanum lycopersicum , Feminino , Animais , Agentes de Controle Biológico/farmacologia , Comportamento Alimentar , Oviposição
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