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1.
Pestic Biochem Physiol ; 202: 105916, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879318

RESUMO

Lambda-cyhalothrin, a representative pyrethroid insecticide widely used for Spodoptera frugiperda control in China, poses challenges due to the development of resistance. This study investigates the realized heritability, inheritance pattern, cross-resistance, and resistance mechanisms to lambda-cyhalothrin. After 21 generations of selection, the lambda-cyhalothrin-resistant strain (G21) developed a 171.11-fold resistance compared to a relatively susceptible strain (RS-G9), with a realized heritability (h2) of 0.11. Cross-resistance assays revealed that lambda-cyhalothrin-resistant strains showed no significant cross-resistance to the majority of tested insecticides. Genetic analysis indicated that lambda-cyhalothrin resistance in S. frugiperda was autosomal, incompletely dominant, and polygenic inheritance. The P450 enzyme inhibitor PBO significantly enhanced lambda-cyhalothrin toxicity in the resistant strains. Compared with the RS-G9 strain, the P450 enzyme activity was significantly increased and multiple P450 genes were significantly up-regulated in the lambda-cyhalothrin-resistant strains. RNAi targeting the most overexpressed P450 genes (CYP337B5 and CYP321B1) significantly increased the susceptibility of resistant S. frugiperda larvae to lambda-cyhalothrin. This study provides comprehensive insights into lambda-cyhalothrin resistance in S. frugiperda, and the results are helpful for developing effective resistance management strategies of this pest.


Assuntos
Sistema Enzimático do Citocromo P-450 , Resistência a Inseticidas , Inseticidas , Nitrilas , Piretrinas , Spodoptera , Animais , Piretrinas/farmacologia , Nitrilas/farmacologia , Spodoptera/efeitos dos fármacos , Spodoptera/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Interferência de RNA , Larva/efeitos dos fármacos , Larva/genética
2.
New Phytol ; 239(1): 255-270, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37148193

RESUMO

As phospholipids of cell membranes, phosphatidylethanolamine (PE) and phosphatidylserine (PS) play crucial roles in glycerophospholipid metabolism. Broadly, some phospholipid biosynthesis enzymes serve as potential fungicide targets. Therefore, revealing the functions and mechanism of PE biosynthesis in plant pathogens would provide potential targets for crop disease control. We performed analyses including phenotypic characterizations, lipidomics, enzyme activity, site-directed mutagenesis, and chemical inhibition assays to study the function of PS decarboxylase-encoding gene MoPSD2 in rice blast fungus Magnaporthe oryzae. The Mopsd2 mutant was defective in development, lipid metabolism, and plant infection. The PS level increased while PE decreased in Mopsd2, consistent with the enzyme activity. Furthermore, chemical doxorubicin inhibited the enzyme activity of MoPsd2 and showed antifungal activity against 10 phytopathogenic fungi including M. oryzae and reduced disease severity of two crop diseases in the field. Three predicted doxorubicin-interacting residues are important for MoPsd2 functions. Our study demonstrates that MoPsd2 is involved in de novo PE biosynthesis and contributes to the development and plant infection of M. oryzae and that doxorubicin shows broad-spectrum antifungal activity as a fungicide candidate. The study also implicates that bacterium Streptomyces peucetius, which biosynthesizes doxorubicin, could be potentially used as an eco-friendly biocontrol agent.


Assuntos
Carboxiliases , Fungicidas Industriais , Magnaporthe , Oryza , Antifúngicos/farmacologia , Fungicidas Industriais/farmacologia , Oryza/microbiologia , Doenças das Plantas/microbiologia , Magnaporthe/genética
3.
BMC Infect Dis ; 23(1): 560, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37641024

RESUMO

INTRODUCTION: Talaromycosis is a common invasive fungal disease in patients with HIV. However, its association with bone destruction is unusual in AIDS patients with talaromycosis. CASE PRESENTATION: This report covers the case of a 38-year-old male AIDS patient coinfected with Talaromyces marneffei and Salmonella. The case, which involved bone destruction, was identified via metagenomic next-generation sequencing (mNGS). Following treatment with a combination of amphotericin B and piperacillin-tazobactam, the patient's elbow motion noticeably improved. Imaging findings revealed that the progression of bony destruction had halted. CONCLUSION: Bone damage due to Talaromyces marneffei infection is infrequent in HIV-positive patients. Therefore, healthcare professionals must be vigilant for potential bone lesions associated with this type of infection. Prompt diagnosis and antimicrobial treatment are crucial.


Assuntos
Síndrome da Imunodeficiência Adquirida , Talaromyces , Masculino , Humanos , Adulto , Salmonella
4.
BMC Infect Dis ; 23(1): 769, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37936073

RESUMO

BACKGROUND: Nontuberculous mycobacteria disease is a common invasive infectious disease in patients with HIV. However, Mycobacterium thermoresistibile association with lymphadenectasis is unusual in AIDS patients. CASE PRESENTATION: This report covers the case of a 25-year-old male AIDS patient infected with Mycobacterium thermoresistibile. The case was identified via pathogen-targeted next-generation sequencing (ptNGS). CONCLUSION: This is the first report of disseminated M. thermoresistibile infection presented with lymphadenectasis in an AIDS patient. Prompt diagnosis and antimicrobial treatment are crucial.


Assuntos
Síndrome da Imunodeficiência Adquirida , Mycobacteriaceae , Infecções por Mycobacterium não Tuberculosas , Masculino , Humanos , Adulto , Síndrome da Imunodeficiência Adquirida/complicações , Infecções por Mycobacterium não Tuberculosas/complicações , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/genética
5.
Ecotoxicol Environ Saf ; 262: 115203, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37406606

RESUMO

Evaluating the sublethal effects of insecticide is crucial for protecting and utilizing natural enemies. In this study, we determined the sublethal effects of acetamiprid and afidopyropen on Harmonia axyridis (Pallas) and explored the potential molecular mechanisms underlying these effects through transcriptomics analysis. The results showed that sublethal concentrations of acetamiprid significantly reduced the adult fecundity and longevity of F0H. axyridis and decreased the survival time and survival rate of the F1 generation. Sublethal concentrations of afidopyropen prolonged the developmental time of 4th instar larvae in the F0 generation. Additionally, acetamiprid and afidopyropen treatments significantly decreased the predation of H. axyridis. Furthermore, transcriptome sequencing analysis revealed that several P450 and UGT genes expressed differently when H. axyridis were exposed to sublethal concentrations of acetamiprid and afidopyropen, suggesting that the differential expression of detoxifying genes might be involved in the response and detoxification metabolism of acetamiprid and afidopyropen in H. axyridis. Our findings demonstrate that sublethal concentrations of acetamiprid adversely influences the development and predation of H. axyridis, while afidopyropen has limited effects on H. axyridis. These results are helpful for protecting and utilizing natural enemies and guiding the scientific use of pesticides in the field.

6.
Pestic Biochem Physiol ; 194: 105522, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532306

RESUMO

Insects are frequently exposed to a range of insecticides that can alter the structure of the commensal microbiome. However, the effects of exposure to non-target pesticides (including non-target insecticides and fungicides) on insect pest microbiomes are still unclear. In the present study, we exposed Nilaparvata lugens to three target insecticides (nitenpyram, pymetrozine, and avermectin), a non-target insecticide (chlorantraniliprole), and two fungicides (propiconazole and tebuconazole), and observed changes in the microbiome's structure and function. Our results showed that both non-target insecticide and fungicides can disrupt the microbiome's structure. Specifically, symbiotic bacteria of N. lugens were more sensitive to non-target insecticide compared to target insecticide, while the symbiotic fungi were more sensitive to fungicides. We also found that the microbiome in the field strain was more stable under pesticides exposure than the laboratory strain (a susceptible strain), and core microbial species g_Pseudomonas, s_Acinetobacter soli, g_Lactobacillus, s_Metarhizium minus, and s_Penicillium citrinum were significantly affected by specifically pesticides. Furthermore, the functions of symbiotic bacteria in nutrient synthesis were predicted to be significantly reduced by non-target insecticide. Our findings contribute to a better understanding of the impact of non-target pesticides on insect microbial communities and highlight the need for scientific and rational use of pesticides.


Assuntos
Fungicidas Industriais , Hemípteros , Inseticidas , Microbiota , Praguicidas , Animais , Inseticidas/toxicidade , Praguicidas/farmacologia , Fungicidas Industriais/farmacologia , Bactérias , Resistência a Inseticidas
7.
Pestic Biochem Physiol ; 194: 105467, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532343

RESUMO

Nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductase (CPR), a crucial electron-transfer partner of P450 systems, is required for various biological reactions catalyzed by P450 monooxygenase. Our previous study indicated that enhanced P450 enzyme detoxification and CYP6ER1 overexpression contributed to sulfoxaflor resistance in Nilaparvata lugens. However, the association between CPR, sulfoxaflor resistance, and neonicotinoid cross-resistance in N. lugens remains unclear. In this study, the sulfoxaflor-resistant (SFX-SEL) (RR = 254.04-fold), resistance-decline (DESEL) (RR = 18.99-fold), and susceptible unselected (UNSEL) strains of N. lugens with the same genetic background were established. Real-time quantitative polymerase chain reaction (RT-qPCR) revealed that the N. lugens CPR (NlCPR) expression level in the SFX-SEL strain was 6.85-fold and 6.07-fold higher than in UNSEL and DESEL strains, respectively. NlCPR expression was significantly higher in the abdomens of UNSEL, DESEL, and SFX-SEL fourth-instar nymphs than in other tissues (thoraxes, heads, and legs). Additionally, sulfoxaflor stress significantly increased NlCPR mRNA levels in the UNSEL, SFX-SEL and DESEL strains. NlCPR silencing by RNA interference (RNAi) dramatically increased the susceptibility of the UNSEL, DESEL, and SFX-SEL strains to sulfoxaflor, but the recovery of SFX-SEL was more obvious. Furthermore, NlCPR silencing led to a significant recovery in susceptibility to nitenpyram, dinotefuran, clothianidin, and thiamethoxam across all strains (UNSEL, DESEL, and SFX-SEL), with the greatest degree of recovery in the sulfoxaflor-resistant strain (SFX-SEL). Our findings suggest that NlCPR overexpression contributes to sulfoxaflor resistance and neonicotinoid cross-resistance in N. lugens. This will aid in elucidating the significance of CPR in the evolution of P450-mediated metabolic resistance in N. lugens.


Assuntos
Hemípteros , Inseticidas , Animais , Inseticidas/farmacologia , NADPH-Ferri-Hemoproteína Redutase/genética , Neonicotinoides/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Hemípteros/metabolismo , Nitrocompostos/farmacologia , Resistência a Inseticidas/genética
8.
Microb Ecol ; 83(4): 1049-1058, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34302509

RESUMO

Understanding the composition of microorganismal communities hosted by insect pests is an important prerequisite for revealing their functions and developing new pest control strategies. Although studies of the structure of the microbiome of Nilaparvata lugens have been published, little is known about the dynamic changes in this microbiome across different developmental stages, and an understanding of the core microbiota is still lacking. In this study, we investigated the dynamic changes in bacteria and fungi in different developmental stages of N. lugens using high-throughput sequencing technology. We observed that the microbial diversity in eggs and mated adults was higher than that in nymphs and unmated adults. We also observed a notable strong correlation between fungal and bacterial α-diversity, which suggests that fungi and bacteria are closely linked and may perform functions collaboratively during the whole developmental period. Arsenophonus and Hirsutella were the predominant bacterial and fungal taxa, respectively. Bacteria were more conserved than fungi during the transmission of the microbiota between developmental stages. Compared with that in the nymph and unmated adult stages of N. lugens, the correlation between bacterial and fungal communities in the mated adult and egg stages was stronger. Moreover, the core microbiota across all developmental stages in N. lugens was identified, and there were more bacterial genera than fungal genera; notably, the core microbiota of eggs, nymphs, and mated and unmated adults showed distinctive functional enrichment. These findings highlight the potential value of further exploring microbial functions during different developmental stages and developing new pest management strategies.


Assuntos
Hemípteros , Microbiota , Animais , Bactérias/genética , Hemípteros/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Ninfa/microbiologia
9.
Pestic Biochem Physiol ; 176: 104875, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34119220

RESUMO

In the present study, the aryl hydrocarbon receptor (AhR) and aryl hydrocarbon receptor nuclear translocator (ARNT) of Nilaparvata lugens were cloned and identified. The NlAhR and NlARNT expression levels significantly increased after imidacloprid, etofenprox and isoprocarb treatments. Knockdowns of NlAhR and NlARNT increased the susceptibility of N. lugens to imidacloprid, etofenprox and isoprocarb, and the detoxification enzyme activities were also significantly decreased. In addition, NlCYP301A1, NlGSTt1 and NlCarE7 were significantly down-regulated after injections of dsNlAhR and dsNlARNT, with the NlCarE7 expression decreasing by greater than 80%. Moreover, after knocking down NlCarE7, the susceptibility of N. lugens to etofenprox and isoprocarb significantly increased. Both NlAhR and NlARNT bound the NlCarE7 promoter and significantly enhanced the transcriptional activity. Our research revealed the functional roles of transcription factors NlAhR and NlARNT in the detoxification metabolism of N. lugens. The results provide a theoretical basis for the pest management and comprehensive control of N. lugens and increase our knowledge of insect toxicology.


Assuntos
Translocador Nuclear Receptor Aril Hidrocarboneto , Hemípteros , Receptores de Hidrocarboneto Arílico , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Hemípteros/genética , Hemípteros/metabolismo , Resistência a Inseticidas/genética , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo
10.
Eur Radiol ; 30(4): 1856-1865, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31900704

RESUMO

BACKGROUND: Tumor shape is strongly associated with some tumor's genomic subtypes and patient outcomes. Our purpose is to find the relationship between risk stratification and the shape of GISTs. METHODS: A total of 101 patients with primary GISTs were confirmed by pathology and immunohistochemistry and underwent enhanced CT examination. All lesions' pathologic sizes were 1 to 10 cm. Points A and B were the extremities of the longest diameter (LD) of the tumor and points C and D the extremities of the small axis, which was the longest diameter perpendicular to AB. The four angles of the quadrangle ABCD were measured and each angle named by its summit (A, B, C, D). For regular lesions, we took angles A and B as big angle (BiA) and small angle (SmA). For irregular lesions, we compared A/B ratio and D/C ratio and selected the larger ratio for analysis. The chi-square test, t test, ROC analysis, and hierarchical or binary logistic regression analysis were used to analyze the data. RESULTS: The BiA/SmA ratio was an independent predictor for risk level of GISTs (p = 0.019). With threshold of BiA at 90.5°, BiA/SmA ratio at 1.35 and LD at 6.15 cm, the sensitivities for high-risk GISTs were 82.4%, 85.3%, and 83.8%, respectively; the specificities were 87.1%, 71%, and 77.4%, respectively; and the AUCs were 0.852, 0.818, and 0.844, respectively. LD could not effectively distinguish between intermediate-risk and high-risk GISTs, but BiA could (p < 0.05). Shape and Ki-67 were independent predictors of the mitotic value (p = 0.036 and p < 0.001, respectively), and the accuracy was 87.8%. CONCLUSIONS: Quantifying tumor shape has better predictive efficacy than LD in predicting the risk level and mitotic value of GISTs, especially for high-risk grading and mitotic value > 5/50HPF. KEY POINTS: • The BiA/SmA ratio was an independent predictor affecting the risk level of GISTs. LD could not effectively distinguish between intermediate-risk and high-risk GISTs, but BiA could. • Shape and Ki-67 were independent predictors of the mitotic value. • The method for quantifying the tumor shape has better predictive efficacy than LD in predicting the risk level and mitotic value of GISTs.


Assuntos
Neoplasias Gastrointestinais/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Feminino , Neoplasias Gastrointestinais/metabolismo , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/cirurgia , Tumores do Estroma Gastrointestinal/metabolismo , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Curva ROC , Medição de Risco , Carga Tumoral
11.
Proc Natl Acad Sci U S A ; 113(45): 12803-12808, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27791095

RESUMO

Mycoviruses are usually transmitted horizontally via hyphal anastomosis and vertically via sexual/asexual spores. Previously, we reported that a gemycircularvirus, Sclerotinia sclerotiorum hypovirulence-associated DNA virus 1 (SsHADV-1), could infect its fungal host extracellularly. Here, we discovered that SsHADV-1 could infect a mycophagous insect, Lycoriella ingenua, and use it as a transmission vector. Virus acquired by larvae feeding on colonies of a virus-infected strain of S. sclerotiorum was replicated and retained in larvae, pupae, adults, and eggs. Virus could be transmitted to insect offspring when larvae were injected with virus particles and allowed to feed on a nonhost fungus. Virus replication in insect cells was further confirmed by inoculating Spodoptera frugiperda cells with virus particles and analyzing with RT-PCR, Northern blot, immunofluorescence, and flow cytometry assays. Larvae could transmit virus once they acquired virus by feeding on virus-infected fungal colony. Offspring larvae hatched from viruliferous eggs were virus carriers and could also successfully transmit virus. Virus transmission between insect and fungus also occurred on rapeseed plants. Virus-infected isolates produced less repellent volatile substances to attract adults of L. ingenua Furthermore, L. ingenua was easily observed on Sclerotinia lesions in rapeseed fields, and viruliferous adults were captured from fields either sprayed with a virus-infected fungal strain or nonsprayed. Our findings may facilitate the exploration of mycoviruses for control of fungal diseases and enhance our understanding of the ecology of SsHADV-1 and other newly emerging SsHADV-1-like viruses, which were recently found to be widespread in various niches including human HIV-infected blood, human and animal feces, insects, plants, and even sewage.

12.
Pestic Biochem Physiol ; 156: 80-86, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31027584

RESUMO

The toxicity of insecticides is associated with a variety of factors including temperature, and global warming is bound to lead to the outbreak of pests; therefore, it is important to study the influence of temperature on insecticide toxicity and pest control. In this study, the influence of temperature on the toxicity of insecticides to Nilaparvata lugens (BPH) was determined. The results showed that the sensitivity of BPH to cycloxaprid (LC50 = 42.5-0.388 mg/L), nitenpyram (LC50 = 3.49-0.187 mg/L), triflumezopyrim (LC50 = 0.354-0.0533 mg/L) and chlorpyrifos (LC50 = 36.3-7.41 mg/L) increased significantly when the temperature changed from 18 °C to 36 °C. BPH sensitivity to etofenprox (LC50 = 9.04-54.2 mg/L) was also affected by temperature. Additionally, the feeding amount and the activities of three detoxification enzymes [cytochrome P450 (P450), glutathione S-transferase (GST) and carboxylesterase (CarE)] of BPH at different temperatures were also measured. The feeding amounts were positively correlated with temperature increases while the activities of P450 and GST were significantly inhibited. The correlation analysis showed that changes in P450 activity (but not GST activity) were closely related to the sensitivity of BPH to cycloxaprid, nitenpyram, chlorpyrifos, and etofenprox according to the variation in temperatures. This study provides a theoretical basis for the rational use of chemical pesticides under the global warming trend and provides a reference for the integrated management of BPH in the field.


Assuntos
Hemípteros/efeitos dos fármacos , Inseticidas/toxicidade , Animais , Clorpirifos/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Compostos Heterocíclicos com 3 Anéis/toxicidade , Resistência a Inseticidas , Neonicotinoides/toxicidade , Piridinas/toxicidade , Temperatura
13.
Pestic Biochem Physiol ; 154: 39-45, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30765055

RESUMO

The brown planthopper, Nilaparvata lugens (Stål), is one of the most economically important rice pests in Asia and has become resistant to various kinds of insecticides, including neonicotinoid insecticides. In this study, an N. lugens clothianidin-resistant (CLR) strain and a susceptible (CLS) strain were established, and the potential resistance mechanisms of N. lugens to clothianidin were elucidated. The cross-resistance studies showed that the clothianidin-resistant strain exhibited cross-resistance to most neonicotinoid insecticides, especially nitenpyram (99.19-fold) and dinotefuran (77.68-fold), while there was no cross-resistance to chlorpyrifos (1.79-fold). The synergism assays and the activities of the detoxification enzymes were performed, and we found that a cytochrome P450 conferred the clothianidin resistance. Two P450 genes (CYP6ER1 and CYP6AY1) were found to be significantly overexpressed in the CLR strain compared with the CLS strain based on qRT-PCR. In addition, the knockdown of CYP6ER1 by RNA interference dramatically increased the toxicity of clothianidin against N. lugens. These data demonstrated that the overexpression of CYP6ER1 could contribute to clothianidin resistance in N. lugens. Our findings will help to improve the design of effective resistance management strategies to control brown planthoppers.


Assuntos
Família 6 do Citocromo P450/genética , Guanidinas/toxicidade , Hemípteros/efeitos dos fármacos , Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Ninfa/efeitos dos fármacos , Tiazóis/toxicidade , Animais , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hemípteros/fisiologia , Ninfa/fisiologia
14.
Pestic Biochem Physiol ; 157: 26-32, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153474

RESUMO

Nitenpyram is very effective in controlling Nilaparvata lugens (brown planthopper, BPH), and its resistance has been reported in field populations; however, the resistance mechanism remains unclear. In the present study, cross-resistance and resistance mechanisms in nitenpyram-resistant BPH were investigated. A resistant strain (NR) with a high resistance level (164.18-fold) to nitenpyram was evolved through successive selection for 42 generations from a laboratory susceptible strain (NS). The bioassay results showed that the NR exhibited cross-resistance to imidacloprid (37.46-fold), thiamethoxam (71.66-fold), clothianidin (149.17-fold), dinotefuran (98.13-fold), sulfoxaflor (47.24-fold), cycloxaprid (9.33-fold), etofenprox (10.51-fold) and isoprocarb (9.97-fold) but not to triflumezopyrim, chlorpyrifos and buprofezin. The NR showed a 3.21-fold increase in cytochrome P450 monooxygenase (P450) activity compared to that in the NS, while resistance was also synergized (4.03-fold) with the inhibitor piperonyl butoxide (PBO), suggesting a role of P450. Furthermore, the mRNA expression levels of cytochrome P450 (CYP) genes by quantitative real-time PCR results indicated that twelve P450 genes were significantly overexpressed in the NR strain, especially CYP6ER1 (203.22-fold). RNA interference (RNAi) suppression of CYP6ER1 through injection of dsCYP6ER1 led to significant susceptibility in the NR strain. The current study expands our understanding of the nitenpyram resistance mechanism in N. lugens, provides an important reference for integrated pest management (IPM), and enriches the theoretical system of insect toxicology.


Assuntos
Hemípteros/efeitos dos fármacos , Neonicotinoides/farmacologia , Animais , Carbamatos/farmacologia , Guanidinas/farmacologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas , Nitrocompostos/farmacologia , Piretrinas/farmacologia , Piridinas/farmacologia , Pirimidinonas/farmacologia , Interferência de RNA , Tiazóis/farmacologia
15.
Pestic Biochem Physiol ; 140: 85-89, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28755699

RESUMO

Indoxacarb belongs to a class of insecticides known as oxadiazines and is the first commercialized pyrazoline-type voltage-dependent sodium channel blocker. A moderate level of resistance to indoxacarb has evolved in field populations of Plutella xylostella from Central China. In the present study, cross-resistance, resistance stability and metabolic mechanisms of indoxacarb resistance were investigated in this moth species. A P. xylostella strain with a high level of resistance to indoxacarb was obtained through continuous selection in the laboratory. The strain showed cross-resistance to metaflumizone, beta-cypermethrin and chlorfenapyr, but no resistance to cyantraniliprole, chlorantraniliprole, abamectin, chlorfluazuron, spinosad and diafenthiuron compared with the susceptible strain. Synergism tests revealed that piperonyl butoxide (PBO) (synergistic ratio, SR=7.8) and diethyl maleate (DEF) (SR=3.5) had considerable synergistic effects on indoxacarb toxicity in the resistant strain (F58). Enzyme activity data showed there was an approximate 5.8-fold different in glutathione S-transferase (GST) and a 6.8-fold different in cytochrome P450 monooxygenase between the resistant strain (F58) and susceptible strain, suggesting that the increased activity of these two enzymes is likely the main detoxification mechanism responsible for the species' resistance to indoxacarb. These results will be helpful for insecticide resistance management strategies to delay the development of indoxacarb resistance in fields.


Assuntos
Resistência a Inseticidas/genética , Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Oxazinas/farmacologia , Animais
16.
Pestic Biochem Physiol ; 139: 53-59, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28595922

RESUMO

The diamondback moth, Plutella xylostella (L.) has developed resistance to many types of insecticides in the field. To study inheritance and fitness cost of metaflumizone resistance, a susceptible strain of diamondback moth was continuously selected with metaflumizone during 37 generations under laboratory conditions. The resistance to metaflumizone was at a high level (resistance ratios from 250.37 to 1450.47-fold). We investigated a metaflumizone resistance strain (G27) and a susceptible strain of P. xylostella, using the age-stage, two-sex life table approach. Compared to the susceptible strain, egg duration, the developmental time of the first and second instar larvae, pupae duration, adult preoviposition period (APOP), total preoviposition period (TPOP), egg hatchability, the survival rate of second instar larva and the mean generation time (T) were significantly differences in the resistant strain. The resistant strain had a relative fitness of 0.78. The inheritance of metaflumizone resistance was also studied by crossing the metaflumizone resistant and susceptible populations. Results revealed an autosomal and incompletely recessive mode of inheritance for metaflumizone resistance in the resistant population of P. xylostella. The present study provided useful information for planning potential management strategies to delay development of metaflumizone resistance in P. xylostella.


Assuntos
Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Semicarbazonas/farmacologia , Animais , Resistência a Inseticidas , Larva/efeitos dos fármacos , Pupa/efeitos dos fármacos
17.
Pestic Biochem Physiol ; 132: 13-20, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27521908

RESUMO

The brown planthopper is a serious rice pest in China. Chemical insecticides have been considered a satisfactory means of controlling the brown planthopper. In the present study, we determined the susceptibility of twenty-one populations of Nilaparvata lugens to eleven insecticides by a rice-stem dipping method from 2012 to 2014 in eight provinces of China. These field-collected populations of N. lugens had developed high levels of resistance to imidacloprid (resistant ratio, RR=233.3-2029-fold) and buprofezin (RR=147.0-1222). Furthermore, N. lugens showed moderate to high levels of resistance to thiamethoxam (RR=25.9-159.2) and low to moderate levels of resistance to dinotefuran (RR=6.4-29.1), clothianidin (RR=6.1-33.6), ethiprole (RR=11.5-71.8), isoprocarb (RR=17.1-70.2), and chlorpyrifos (RR=7.4-30.7). In contrast, the susceptibility of N. lugens to etofenprox (RR=1.1-4.9), thiacloprid (RR=2.9-8.2) and acetamiprid (RR=2.7-26.2) remained susceptible to moderate levels of resistance. Significant correlations were detected between the LC50 values of imidacloprid and thiamethoxam, dinotefuran, buprofezin, and etofenprox, as well as between clothianidin and thiamethoxam, dinotefuran, ethiprole, acetamiprid, and thiacloprid. Similarly, significant correlations were observed between chlorpyrifos and etofenprox, acetamiprid and thiacloprid. Additionally, the activity of the detoxification enzymes of N. lugens showed a significant correlation with the log LC50 values of imidacloprid, dinotefuran and ethiprole. These results will be beneficial for effective insecticide resistance management strategies to prevent or delay the development of insecticide resistance.


Assuntos
Resistência a Inseticidas , Inseticidas , Animais , Carbamatos , China , Clorpirifos , Guanidinas , Hemípteros/química , Hemípteros/efeitos dos fármacos , Imidazóis , Inseticidas/análise , Neonicotinoides , Nitrocompostos , Oxazinas , Pirazóis , Piretrinas , Piridinas , Tiadiazinas , Tiametoxam , Tiazinas , Tiazóis
18.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(3): 308-11, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24758082

RESUMO

OBJECTIVE: To explore Chinese medical syndrome distribution features of Japanese encephalitis (JE), and to analyze its correlation between syndromes and features of etiologies and pathogeneses. METHODS: Recruited were 277 patients with confirmative diagnosis of JE from Wuhan Medical Treatment Center, Children's Hospital Affiliated to Chongqing Medical University, Fifth People's Hospital of Guiyang City, Hangzhou Sixth People's Hospital, and Chengdu Hospital of Infectious Diseases between July to September 2012. Chinese medical syndrome distribution features were summarized from their general materials and detailed records of clinical data, including medical history, symptoms and signs, tongue fur, and pulse figures.The frequency of symptoms and signs was calculated according to mild, ordinary, severe, extreme severe degrees. The distribution of Chinese medical syndromes was summarized. And its correlation between syndromes and features of etiologies and pathogeneses were analyzed. RESULTS: After clustering analysis, Chinese medical syndromes of JE could be categorized as four groups: toxicity accumulation in Fei and Wei syndrome (TAFWS), brain collateral impaired by poison syndrome (BCIPS), depression of toxicity in the pericardium syndrome (DTPS), exhaustion of yin and yang syndrome (EYYS). BCIPS and DTPS were dominated, accounting for 74.0% (205 cases). The main causes covered evil of summer heat [accounting for 92.42% (256/277 cases)], heat [accounting for 87.73% (243/277 cases)], and toxin [accounting for 99.64% (276/277 cases)]. CONCLUSIONS: The four Chinese medical syndrome types of JE met Chinese medical clinical features of encephalitis. It is induced by infestation of dampness-heat, resulting in toxicity accumulation in Fei and Wei, brain collateral impaired by poison, depression of toxicity in the pericardium. Yin fluid and blood is exhausted as time goes by. Qi and yin are impaired to form intermingled deficiency and excess, and finally causing exhaustion of yin and yang.


Assuntos
Encefalite Japonesa/diagnóstico , Encefalite Japonesa/patologia , Medicina Tradicional Chinesa/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Deficiência da Energia Yang/diagnóstico , Deficiência da Energia Yin/diagnóstico
19.
Infect Drug Resist ; 17: 1431-1437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38623529

RESUMO

Introduction: Kaposi sarcoma (KS) incidence has decreased since the initiation of combination antiretroviral therapy (cART), but it remains the most common cancer in people with HIV/AIDS (PWHA). PWHA with advanced immunosuppression who initiate antiretroviral therapy are susceptible to the occurrence of an immune reconstitution inflammatory syndrome (IRIS). Case Presentation: This report covers the case of a 25-year-old male with AIDS-related KS who relapsed after Liposomal Doxorubicin, but recovered well after administration of nab-paclitaxel (Nab-PTX). Conclusion: This is a rare case in choosing Nab-PTX to treat relapsed AIDS-KS and get good feedback. We report the case to provide a possible solution to treat AIDS-KS.

20.
J Agric Food Chem ; 72(21): 12146-12155, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38747516

RESUMO

In this study, an α-amylase-responsive controlled-release formulation was developed by capping polydopamine onto ß-cyclodextrin-modified abamectin-loaded hollow mesoporous silica nanoparticles. The prepared Aba@HMS@CD@PDA were subjected to characterization using various analytical techniques. The findings revealed that Aba@HMS@CD@PDA, featuring a loading rate of 18.8 wt %, displayed noteworthy release behavior of abamectin in the presence of α-amylase. In comparison to abamectin EC, Aba@HMS@CD@PDA displayed a significantly foliar affinity and improved rainfastness on lotus leaves. The results of field trail demonstrated a significantly higher control efficacy against Spodoptera litura Fabricius compared to abamectin EC at all concentrations after 7, 14, and 21 days of spaying, showcasing the remarkable persistence of Aba@HMS@CD@PDA. These results underscore the potential of Aba@HMS@CD@PDA as a novel and persistently effective strategy for sustainable on-demand crop protection. The application of nanopesticides can enhance the effectiveness and efficiency of pesticide utilization, contributing to more sustainable agricultural practices.


Assuntos
Proteção de Cultivos , Inseticidas , Nanopartículas , Spodoptera , alfa-Amilases , Animais , alfa-Amilases/química , alfa-Amilases/metabolismo , alfa-Amilases/antagonistas & inibidores , Nanopartículas/química , Proteção de Cultivos/métodos , Spodoptera/efeitos dos fármacos , Inseticidas/química , Inseticidas/farmacologia , Ivermectina/análogos & derivados , Ivermectina/química , Ivermectina/farmacologia , Polímeros/química , Dióxido de Silício/química , Controle de Insetos , Praguicidas/química , Praguicidas/farmacologia , Indóis/química , Indóis/farmacologia
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