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1.
Pest Manag Sci ; 79(6): 2206-2219, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36750418

ABSTRACT

BACKGROUND: Spodoptera frugiperda (J. E. Smith) is a widespread agricultural pest with several records of resistance to different insecticides and Bt proteins, including the neurotoxic insecticides chlorpyrifos (organophosphate) and lambda-cyhalothrin (pyrethroid). Here, we (i) characterized and monitored the susceptibility of field populations of S. frugiperda to chlorpyrifos (194 populations) and lambda-cyhalothrin (197 populations) collected from major maize-growing regions of Brazil from 2003 to 2016, and (ii) compared gene expression levels of laboratory-selected, chlorpyrifos- and lambda-cyhalothrin-resistant strains to a susceptible reference strain (Sf-ss) of S. frugiperda. RESULTS: The susceptibility monitoring detected average survival ranging from 29.3% to 36.0% for chlorpyrifos, and 23.1% to 68.0% for lambda-cyhalothrin. The resistance ratio of the chlorpyrifos-resistant strain (Clo-rr) was 25.4-fold and of the lambda-cyhalothrin-resistant strain (Lam-rr) was 21.5-fold. We identified 1098 differentially expressed genes (DEGs) between Clo-rr and Sf-ss, and 303 DEGs between Lam-rr and Sf-ss. Functional analyses of the DEGs revealed the up-regulation of several detoxification enzymes, mainly cytochrome P450 belonging to CYP3 and CYP6 clans. Genes associated with regulatory processes, such as the forkhead box class O (FoxO) transcription factor were also up-regulated. Variant analysis of target-site mutations for both pesticides identified the A201S and F290V mutations in acetylcholinesterase-1, both occurring in heterozigosis in the Clo-rr S. frugiperda strain. CONCLUSION: Our data show that the overexpression of the enzymatic detoxification machinery is the main difference to explain the resistance of Clo-rr and Lam-rr strains of S. frugiperda to chlorpyrifos and lambda-cyhalothrin, although a target-site mutation also contributes to the Clo-rr resistance to chlorpyrifos. © 2023 Society of Chemical Industry.


Subject(s)
Chlorpyrifos , Insecticides , Pyrethrins , Animals , Insecticides/pharmacology , Chlorpyrifos/pharmacology , Spodoptera/genetics , Acetylcholinesterase/genetics , Insecticide Resistance/genetics , Pyrethrins/pharmacology , Gene Expression
2.
Hematol., Transfus. Cell Ther. (Impr.) ; 44(2): 156-162, Apr.-June 2022. tab
Article in English | LILACS | ID: biblio-1385046

ABSTRACT

Abstract Introduction Studies have shown that the loss of the FOXO3 transcriptional function is involved in the pathophysiology of some chronic erythroid disorders, including beta-thalassemia (β-thal). Therefore, the single nucleotide polymorphism (SNP) rs3800231 (35-2764A > G) could contribute to alterations in its transcriptional activity, acting as a modifier of β-thal phenotypic manifestations. Objective and method In order to better understand the genotypic and/or allelic distributions among β-thal patients, we evaluated 83 β-thal heterozygous and 20 homozygous, compared to 117 individuals without hemoglobinopathies (control group). Additionally, we verified any influence of the FOXO3 polymorphism on clinical manifestations among β-thal homozygotes. Results We obtained higher frequencies of the wild-type homozygous (AA) and the wild-type allele (A) in the β-thal group (p< 0.0001 and p= 0.00014, respectively). The most common clinical manifestations found among β-thal homozygotes were iron overload (90%), splenomegaly (65%) and bone complications (35%), e.g., osteopenia/osteoporosis. We observed that close to 80% of the patients presenting such manifestations had the genotype AA. However, we did not find any significant involvement of the FOXO3 polymorphism in clinical manifestation occurrences. Conclusion Thus, we concluded that the SNP rs3800231 did not play a significant role as a modifier of the clinical manifestations observed in the β-thal homozygotes studied.


Subject(s)
Humans , Male , Female , Adult , beta-Thalassemia/genetics , Forkhead Box Protein O3 , Polymorphism, Genetic , Signs and Symptoms
3.
Hematol Transfus Cell Ther ; 44(2): 156-162, 2022.
Article in English | MEDLINE | ID: mdl-33309469

ABSTRACT

INTRODUCTION: Studies have shown that the loss of the FOXO3 transcriptional function is involved in the pathophysiology of some chronic erythroid disorders, including beta-thalassemia (ß-thal). Therefore, the single nucleotide polymorphism (SNP) rs3800231 (35-2764A > G) could contribute to alterations in its transcriptional activity, acting as a modifier of ß-thal phenotypic manifestations. OBJECTIVE AND METHOD: In order to better understand the genotypic and/or allelic distributions among ß-thal patients, we evaluated 83 ß-thal heterozygous and 20 homozygous, compared to 117 individuals without hemoglobinopathies (control group). Additionally, we verified any influence of the FOXO3 polymorphism on clinical manifestations among ß-thal homozygotes. RESULTS: We obtained higher frequencies of the wild-type homozygous (AA) and the wild-type allele (A) in the ß-thal group (p < 0.0001 and p = 0.00014, respectively). The most common clinical manifestations found among ß-thal homozygotes were iron overload (90%), splenomegaly (65%) and bone complications (35%), e.g., osteopenia/osteoporosis. We observed that close to 80% of the patients presenting such manifestations had the genotype AA. However, we did not find any significant involvement of the FOXO3 polymorphism in clinical manifestation occurrences. CONCLUSION: Thus, we concluded that the SNP rs3800231 did not play a significant role as a modifier of the clinical manifestations observed in the ß-thal homozygotes studied.

4.
Insect Mol Biol ; 30(3): 277-286, 2021 06.
Article in English | MEDLINE | ID: mdl-33427366

ABSTRACT

Social insects are notable for having two female castes that exhibit extreme differences in their reproductive capacity. The molecular basis of these differences is largely unknown. Vitellogenin (Vg) is a powerful antioxidant and insulin-signalling regulator used in oocyte development. Here we investigate how Royal Jelly (the major food of honeybee queens) and queen mandibular pheromone (a major regulator of worker fertility), affect the longevity and reproductive status of honey bee workers, the expression of Vg, its receptor VgR and associated regulatory proteins. We find that Vg is expressed in the ovaries of workers and that workers fed a queen diet of Royal Jelly have increased Vg expression in the ovaries. Surprisingly, we find that expression of Vg is not associated with ovary activation in workers, suggesting that this gene has potentially acquired non-reproductive functions. Therefore, Vg expression in the ovaries of honeybee workers provides further support for the Ovarian Ground Plan Hypothesis, which argues that genes implicated in the regulation of reproduction have been co-opted to regulate behavioural differences between queens and workers.


Subject(s)
Bees/physiology , Biological Evolution , Gene Expression , Insect Proteins/genetics , Life History Traits , Vitellogenins/genetics , Animals , Bees/genetics , Female , Insect Proteins/metabolism , Ovary/metabolism , Reproduction/genetics , Social Behavior , Vitellogenins/metabolism
5.
Tissue Barriers ; 3(1-2): e978720, 2015.
Article in English | MEDLINE | ID: mdl-25838983

ABSTRACT

The barrier properties of endothelial cells are critical for the maintenance of water and protein balance between the intravascular and extravascular compartments. An impairment of endothelial barrier function has been implicated in the genesis and/or progression of a variety of pathological conditions, including pulmonary edema, ischemic stroke, neurodegenerative disorders, angioedema, sepsis and cancer. The altered barrier function in these conditions is often linked to the release of soluble mediators from resident cells (e.g., mast cells, macrophages) and/or recruited blood cells. The interaction of the mediators with receptors expressed on the surface of endothelial cells diminishes barrier function either by altering the expression of adhesive proteins in the inter-endothelial junctions, by altering the organization of the cytoskeleton, or both. Reactive oxygen species (ROS), proteolytic enzymes (e.g., matrix metalloproteinase, elastase), oncostatin M, and VEGF are part of a long list of mediators that have been implicated in endothelial barrier failure. In this review, we address the role of blood borne cells, including, neutrophils, lymphocytes, monocytes, and platelets, in the regulation of endothelial barrier function in health and disease. Attention is also devoted to new targets for therapeutic intervention in disease states with morbidity and mortality related to endothelial barrier dysfunction.

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