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1.
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
2.
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
3.
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
4.
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
5.
Plant J ; 112(3): 694-708, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36086899

RESUMO

Rapid callose accumulation has been shown to mediate defense in certain plant-virus interactions. Exposure to the green leaf volatile (Z)-3-hexenol (Z-3-HOL) can prime tomato (Solanum lycopersicum) for an enhanced defense against subsequent infection by whitefly-transmitted Tomato yellow leaf curl virus (TYLCV). However, the molecular mechanisms affecting Z-3-HOL-induced resistance are poorly understood. Here, we explored the mechanisms underlying Z-3-HOL-induced resistance against whitefly-transmitted TYLCV infection and the role of callose accumulation during this process. Tomato plants pre-treated with Z-3-HOL displayed callose priming upon whitefly infestation. The callose inhibitor 2-deoxy-d-glucose abolished Z-3-HOL-induced resistance, confirming the importance of callose in this induced resistance. We also found that Z-3-HOL pre-treatment enhanced salicylic acid levels and activated sugar signaling in tomato upon whitefly infestation, which increased the expression of the cell wall invertase gene Lin6 to trigger augmented callose deposition against TYLCV infection resulting from whitefly transmission. Using virus-induced gene silencing, we demonstrated the Lin6 expression is relevant for sugar accumulation mediated callose priming in restricting whitefly-transmitted TYLCV infection in plants that have been pre-treated with Z-3-HOL. Moreover, Lin6 induced the expression of the callose synthase gene Cals12, which is also required for Z-3-HOL-induced resistance of tomato against whitefly-transmitted TYLCV infection. These findings highlight the importance of sugar signaling in the priming of callose as a defense mechanism in Z-3-HOL-induced resistance of tomato against whitefly-transmitted TYLCV infection. The results will also increase our understanding of defense priming can be useful for the biological control of viral diseases.


Assuntos
Begomovirus , Hemípteros , Solanum lycopersicum , Animais , Begomovirus/genética , Solanum lycopersicum/genética , Hemípteros/genética , Doenças das Plantas/genética , Açúcares
6.
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
7.
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
8.
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
9.
Immunopharmacol Immunotoxicol ; 45(1): 83-88, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35997274

RESUMO

BACKGROUND: To assess the clinical value of serum complement component 1q (C1q) and immunoglobulin G (IgG) levels in predicting the response to combined immunotherapy in patients with esophageal squamous cell carcinoma. METHODS: We conducted a retrospective study of 44 patients with esophageal squamous cell carcinoma who received combined immunotherapy in our hospital. Serum IgG and C1q levels were collected before and three weeks after immunotherapy treatment, together with other data on clinical and demographic characteristics. RESULTS: Twenty seven patients (61.4%) showed partial response (PR), 13 (29.5%) stable disease (SD), and 4 (9.1%) progressive disease (PD). None of the patients presented complete response (CR). The PR group displayed lower IgG and higher C1q levels both before and after immunotherapy than patients showing SD or PD. The IgG reduction (59.3%) and C1q increment (70.3%) in the PR group three weeks post-treatment were significantly larger than those in patients showing SD or PD. Moreover, the pretreatment C1q level and the post-treatment change of C1q levels were strongly associated with the immunotherapy response. CONCLUSIONS: High pre- and post-treatment C1q levels and reduced post-treatment IgG levels correlate with efficacy of combined immunotherapy in patients with esophageal squamous cell carcinoma. Serum baseline C1q level may predict immunotherapy response in such patients.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/terapia , Complemento C1q , Estudos Retrospectivos , Neoplasias Esofágicas/terapia , Imunoglobulina G , Imunoterapia
10.
Mol Ther ; 27(6): 1114-1125, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30962163

RESUMO

By fusing the extracellular domain of the natural killer (NK) cell receptor NKG2D to DAP12, we constructed a chimeric antigen receptor (CAR) to improve NK cell tumor responses. An RNA electroporation approach that provides transient expression of the CAR was adopted as a risk mitigation strategy. Expression of the NKG2D RNA CAR significantly augmented the cytolytic activity of NK cells against several solid tumor cell lines in vitro and provided a clear therapeutic benefit to mice with established solid tumors. Three patients with metastatic colorectal cancer were then treated with local infusion of the CAR-NK cells. Reduction of ascites generation and a marked decrease in number of tumor cells in ascites samples were observed in the first two patients treated with intraperitoneal infusion of low doses of the CAR-NK cells. The third patient with metastatic tumor sites in the liver was treated with ultrasound-guided percutaneous injection, followed by intraperitoneal infusion of the CAR-NK cells. Rapid tumor regression in the liver region was observed with Doppler ultrasound imaging and complete metabolic response in the treated liver lesions was confirmed by positron emission tomography (PET)- computed tomographic (CT) scanning. Our results highlight a promising therapeutic potential of using RNA CAR-modified NK cells to treat metastatic colorectal cancer.


Assuntos
Transferência Adotiva/métodos , Transplante de Células/métodos , Neoplasias Colorretais/terapia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/transplante , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Receptores de Antígenos Quiméricos/imunologia , Transferência Adotiva/efeitos adversos , Animais , Engenharia Celular/métodos , Transplante de Células/efeitos adversos , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Citotoxicidade Imunológica/genética , Estudos de Viabilidade , Feminino , Vetores Genéticos , Células HCT116 , Humanos , Células Matadoras Naturais/metabolismo , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Projetos Piloto , RNA Mensageiro/genética , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Zhongguo Zhong Yao Za Zhi ; 44(24): 5363-5367, 2019 Dec.
Artigo em Zh | MEDLINE | ID: mdl-32237381

RESUMO

As a natural plant source of artemisinin,a first-line drug against malaria,Artemisia annua directly affects the extraction process of artemisinin and the source of artemisinin. At present,traditional breeding methods combined with tissue culture are often used to breed high-yield artemisinin-containing new varieties of A. annua. However,the breeding method has the disadvantages of low efficiency and continuous selection. In this study,heavy ion beam irradiation technology was used to observe the specific germplasm resources of A. annua,and the morphological characteristics,agronomic traits and artemisinin content were used as indicators to observe the selection materials and materials. The cultivated new varieties were compared with trials and regional trials. In addition,the new variety of A. annua was identified by SRAP molecular marker technology. The results showed that the new variety of A. annua, " Kehao No.1",had an average yield of 235. 0 kg of dry leaf per mu,which was more than 20% higher than that of the control. Especially,the average artemisinin content was 2. 0%,which was 45% higher than that of the control,and the " Kehao No.1" has high anti-white powder disease,high-yield and high-quality new varieties. Therefore,mutagenic breeding of heavy ion beam irradiation can significantly improve the yield and artemisinin content of the " Kehao No. 1" and it has a good promotion value.


Assuntos
Artemisia annua/genética , Artemisininas/análise , Melhoramento Vegetal , Plantas Medicinais/genética , Artemisia annua/química , Íons Pesados , Mutagênese , Fenótipo , Plantas Medicinais/química
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(6): 891-894, 2018 Nov.
Artigo em Zh | MEDLINE | ID: mdl-32677399

RESUMO

OBJECTIVE: To investigate the expressions of sphingosine 1-phosphate (S1P) and S1P G-protein-coupled receptor 1 (S1PR1) in pulmonary ischemia reperfusion injury (PIRI) tissues and explore their relationship. METHODS: The model of PIRI was established in vivo male C57BL/6 mice (n=8). The left pulmonary hilum was occluded for 30 min with a microvascular clamp through a left thoracotomy. Reperfusion began with removal of the clamp. Normal group (n=8) and sham group (n=8) were set as control. The hematoxylin and eosin (HE) staining of ultrastructural changes and wet-to-dry mass ratio in lung tissues were measured for judging the succeed model. The mRNA expressions of sphingosine kinase 1 (SphK1) and S1PR1 were determined by real-time PCR, and ELISA was used to detect the concentrations of S1P and S1PR1 in the lung tissues. RESULTS: The mRNA expressions of SphK1, S1PR1 and the concentrations of S1P and S1PR1 and wet-to-dry mass ratio of the lung tissues in ischemia-reperfusion mice were higher than those normal mice and sham operation mice (P<0.05). CONCLUSIONS: The increased expressions of S1P and S1PR1 in lung tissues after PIRI suggest that the S1P/S1PR1 signal pathway is involved in the pathophysiological process of PIRI, and may be a potential therapeutic target for it.

13.
Microb Pathog ; 113: 412-415, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29170040

RESUMO

Chronic hepatitis B (CHB) infection is a typical inflammatory disease characterized by a dysregulated expression of cytokines, which contributes to the pathogenesis of chronic Hepatitis B virus (HBV) infection. IL-36 cytokines (IL-36α, IL-36ß, IL-36γ and IL-36Ra) are important players in infection and immunity. However, their roles in the pathogenesis of chronic HBV infection remain unknown. Here the circulating concentrations of IL-36 cytokines from 50 CHB patients and 30 healthy controls were determined by enzyme-linked immunosorbent assay (ELISA). Sera concentrations of IL-36α were found to be significantly elevated in CHB patients, while the concentrations of IL-36ß, IL-36γ and IL-36Ra were not significantly different in comparison to healthy donors. Furthermore, increased IL-36α concentrations correlated positively with HBV-DNA levels in CHB patients. Our study suggests that IL-36α production was up-regulated during CHB infection, which could be directly related to HBV-DNA loads in CHB patients. The immunoregulatory role of IL-36α in the pathogenesis of chronic HBV infection should be further studied.


Assuntos
Citocinas/metabolismo , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Interleucina-1/metabolismo , Carga Viral/imunologia , Adulto , Povo Asiático , Citocinas/sangue , DNA Viral , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Inflamação/imunologia , Interleucina-1/sangue , Masculino , Pessoa de Meia-Idade
14.
Pest Manag Sci ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984846

RESUMO

BACKGROUND: Elucidating fitness cost associated with field-evolved insect resistance to insecticide is of particular importance to current sustainable pest control. The global pest whitefly Bemisia tabaci has developed resistance to many members of neonicotinoids, but little is known about whitefly resistance to neonicotinoid nitenpyram and its associated fitness cost. Using insecticide bioassay and life-table approach, this study aims to investigate nitenpyram resistance status in field-collected whitefly populations, and to explore whether such resistance is accompanied by a fitness cost. RESULTS: The bioassay results revealed that 14 of 29 whitefly populations displayed moderate to extremely high resistance to nitenpyram, demonstrating a widespread field-evolved resistance to nitenpyram. This field-evolved resistance in the whitefly has increased gradually over the past 3 years from 2021 to 2023. Further life-table study showed that two resistant whitefly populations exhibited longer developmental time, shorter lifespans of adult, and lower fecundity compared with the most susceptible population. The relative fitness cost of the two resistant populations was calculated as 0.69 and 0.56 by using net productive rate R0, which suggests that nitenpyram resistance comes with fitness cost in the whitefly, especially on reproduction. CONCLUSION: Overall, these results represent field-evolved high resistance to nitenpyram in the whitefly. The existing fitness costs associated with nitenpyram resistance are helpful to propose a suitable strategy for sustainable control of whiteflies by rotation or mixture of insecticide with different modes of action. © 2024 Society of Chemical Industry.

15.
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
16.
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
17.
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
18.
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
19.
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.

20.
Zhonghua Yi Xue Za Zhi ; 93(19): 1490-3, 2013 May 21.
Artigo em Zh | MEDLINE | ID: mdl-24029575

RESUMO

OBJECTIVE: To discuss the role of sonic hedgehog (SHH) pathway in PDGF-induced vascular smooth muscle cell proliferation. METHOD: Human vein VSMC were cultured in vitro. Laser confocal microscopy and Western blot were used to detect the expression of SHH pathway related proteins. The cell proliferation was evaluated by Ki-67 staining and BrdU incorporation after treatment by siRNA of Gli2 or shh pathway inhibitor cyclopamine. RESULTS: The results of laser confocal microscopy and Western blot showed that SHH pathway protein which including shh, Patched1 and Gli2 were activated in the PDGF-induced VSMC proliferation.BrdU incorporation assay and Ki-67 staining showed that the cell proliferation which induced by PDGF was inhibited by Gli2-siRNA and cyclopamine which can both block SHH pathway. CONCLUSION: SHH pathway play an important role in PDGF-induced VSMC proliferation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Proteínas Hedgehog/metabolismo , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Células Cultivadas , Humanos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Transdução de Sinais
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