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3.
Vet Rec ; 186(15): 496-497, 2020 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-32358121
4.
Iran J Kidney Dis ; 14(3): 167-172, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32361692

RESUMO

Coronaviruses primarily cause zoonotic infections, however in the past few decades several interspecies transmissions have occurred, the last one by SARS-CoV-2, causing COVID-19 pandemic, posing serious threat to global health. The SARS-CoV-2 spike (S) protein plays an important role in viral attachment, fusion and entry. However, other structural and non-structural SARS-CoV-2 proteins are potential influencers in virus pathogenicity. Among these proteins; Orf3, Orf8, and Orf10 show the least homology to SARSCoV proteins and therefore should be further studied for their abilities to modulate antiviral and inflammatory responses. Here, we discuss how SARS-COV-2 interacts with our immune system.


Assuntos
Betacoronavirus , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Genoma Viral/genética , Sistema Imunitário/virologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Proteínas Virais/genética , Proteínas Virais/metabolismo , Animais , Betacoronavirus/genética , Betacoronavirus/imunologia , Ordem dos Genes , Humanos , Pandemias , Vírus da SARS/genética , Vírus da SARS/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Estruturas Virais/genética , Internalização do Vírus
6.
J Environ Manage ; 264: 110349, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32364957

RESUMO

Biological invasions are one of the major threats to biodiversity at the global scale, causing numerous environmental impacts and having high direct and indirect costs associated with their management, control and eradication. In this work, we present a system-dynamic modelling approach for the biocontrol of the invasive plant species Alternanthera philoxeroides using its natural predator, Agasicles hygrophila, as a biocontrol agent. We have simulated different scenarios in the Finisterre region (Spain), where a single population of the invasive plant has been recently described. To assess the effectiveness of A. hygrophila as a biocontrol agent in the region, a population dynamic model was developed in order to include the life-cycle of both species, as well as the interaction among them. The results of the simulations indicate that the control of this new invasive plant is possible, as long as several releases of the biocontrol agent are made over time. The proposed model can support the control or even the eradication of the population of A. philoxeroides with a minimal impact on the environment. Additionally, the proposed framework also represents a versatile dynamic tool, adjustable to different local management specificities (objectives and parameters) and capable of responding under different contexts. Hence, this approach can be used to guide eradication efforts of new invasive species, to improve the applicability of early management measures as biocontrol, and to support decision-making by testing several alternative management scenarios.


Assuntos
Amaranthaceae , Besouros , Animais , Espécies Introduzidas , Plantas , Espanha
7.
Biosens Bioelectron ; 159: 112214, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32364936

RESUMO

Recent advances in electrochemical biosensors for pathogen detection are reviewed. Electrochemical biosensors for pathogen detection are broadly reviewed in terms of transduction elements, biorecognition elements, electrochemical techniques, and biosensor performance. Transduction elements are discussed in terms of electrode material and form factor. Biorecognition elements for pathogen detection, including antibodies, aptamers, and imprinted polymers, are discussed in terms of availability, production, and immobilization approach. Emerging areas of electrochemical biosensor design are reviewed, including electrode modification and transducer integration. Measurement formats for pathogen detection are classified in terms of sample preparation and secondary binding steps. Applications of electrochemical biosensors for the detection of pathogens in food and water safety, medical diagnostics, environmental monitoring, and bio-threat applications are highlighted. Future directions and challenges of electrochemical biosensors for pathogen detection are discussed, including wearable and conformal biosensors, detection of plant pathogens, multiplexed detection, reusable biosensors for process monitoring applications, and low-cost, disposable biosensors.


Assuntos
Bactérias/isolamento & purificação , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas , Eucariotos/isolamento & purificação , Técnicas Microbiológicas/instrumentação , Vírus/isolamento & purificação , Animais , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Eletrodos , Humanos , Técnicas Microbiológicas/normas , Técnicas Microbiológicas/tendências , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia
9.
Pol Merkur Lekarski ; 48(284): 112-119, 2020 Apr 22.
Artigo em Polonês | MEDLINE | ID: mdl-32352944

RESUMO

According to the Situation Report 65 of the World Health Organization of March 25, 2020, the COVID-19 incidence rate indicates 413 467 confirmed cases and 18 433 deaths. Genetic diversification of the Corona virus has resulted in strains that cause severe respiratory tract infections in humans via drip and animal mediation. S-proteins covering its surface, which bind to the cell receptor - angiotensin converting enzyme 2 (ACE-2) and transmembrane serine protease (TMPRSS2) are important in shaping virus activity. The course of infection varies from mild to severe. The ability to control infection is limited because there are no drugs that fully inhibit 2019-nCoV. Interferon-alpha (5 million U twice daily by inhalation), lopinavir/ritonavir (400/100 mg twice daily orally), as well as chloroquine (500 mg twice daily orally for 10 days) and azithromycin (500 mg twice per day) cause a milder course of the disease and reduce the duration of treatment. The administration of glucocorticosteroids and research drugs (tocilizumab) is acceptable for massive infiltrative lesions in the pulmonary parenchyma causing severe lung injury (ALI) and acute respiratory distress syndrome (ARDS). In the system operation it is necessary to create the socalled a safety matrix that would take into account the existing threat on the one hand and all available services and resources on the other. Precise analysis and separation of individual tasks can enable the creation of a real crisis management plan.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus , Coronavirus , Pandemias , Pneumonia Viral , Animais , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Gestão de Recursos da Equipe de Assistência à Saúde , Humanos , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão
11.
Pestic Biochem Physiol ; 165: 104553, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359535

RESUMO

Thrips tabaci is a key pest of onions, especially in the Pacific Northwestern USA. Management of T. tabaci is dominated by the application of various insecticides. However, T. tabaci is known to develop insecticide resistance which possibly leads to control failures, crop loss, and environmental concern. Here, we evaluated resistance status of T. tabaci populations from conventional and organic commercial onion fields to three widely used insecticides: oxamyl, methomyl, and abamectin with on-field concentration-mortality bioassays. The biochemistry and molecular mechanisms underlying resistance to these insecticides were also investigated by using enzymatic assays and detecting resistance-associated mutations. Field-evolved resistance to oxamyl, methomyl and abamectin were detected in most of the T. tabaci populations collected from conventional onion farms. At the labeled field rate, all the tested insecticides, particularly methomyl and oxamyl, had significantly reduced efficacy. Enzymatic assays of insecticide target and detoxification enzymes indicated that T. tabaci populations in Western USA onions harbor multiple mechanisms of resistance including enhanced activities of detoxification enzymes and target site insensitivity. Our results provide new information in understanding the dynamics of T. tabaci adaptation to multiple insecticides, which will help to design sustainable insecticide resistance management strategies for T. tabaci. Furthermore, this study provides the foundation for future research in identifying the biochemical and molecular markers associated with insecticide resistance in T. tabaci.


Assuntos
Inseticidas , Tisanópteros , Animais , Resistência a Inseticidas , Metomil , Cebolas
12.
Pestic Biochem Physiol ; 165: 104552, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359537

RESUMO

The fruit fly, Drosophila melanogaster, is predominantly found in overripe, rotten, fermenting, or decaying fruits and is constantly exposed to chemical stressors such as acetic acid, ethanol, and 2-phenylethanol. D. melanogaster has been employed as a model system for studying the molecular bases of various types of chemical-induced tolerance. Expression profiling using Illumina sequencing has been performed for identifying changes in gene expression that may be associated with evolutionary adaptation to exposure of acetic acid, ethanol, and 2-phenylethanol. We identified a total of 457 differentially expressed genes that may affect sensitivity or tolerance to three chemicals in the chemical treatment group as opposed to the control group. Gene-set enrichment analysis revealed that the genes involved in metabolism, multicellular organism reproduction, olfaction, regulation of signal transduction, and stress tolerance were over-represented in response to chemical exposure. Furthermore, we also detected a coordinated upregulation of genes in the Toll- and Imd-signaling pathways after the chemical exposure. Quantitative reverse transcription PCR analysis revealed that the expression levels of nine genes within the set of genes identified by RNA sequencing were up- or downregulated owing to chemical exposure. Taken together, our data suggest that such differentially expressed genes are coordinately affected by chemical exposure. Transcriptional analyses after exposure of D. melanogaster with three chemicals provide unique insights into subsequent functional studies on the mechanisms underlying the evolutionary adaptation of insect species to environmental chemical stressors.


Assuntos
Ácido Acético , Drosophila melanogaster , Animais , Drosophila , Etanol , Perfilação da Expressão Gênica , Álcool Feniletílico
13.
Pestic Biochem Physiol ; 165: 104544, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359538

RESUMO

The present study was aimed to evaluate the toxic effects of quinestrol (a synthetic estradiol) in male lesser bandicoot rat, Bandicota bengalensis. Effect was studied on body weight, weight of vital organs, changes in level of biochemical parameters and genotoxicity. Feeding of bait containing 0.01% quinestrol in bi-choice and 0.02 and 0.03% quinestrol in no-choice for a period of 10 days resulted in total ingestion of 19.50, 67.60 and 243.30 mg/kg bwt, respectively of the active ingredient. Autopsy of rats after 15 and 30 days of treatment withdrawal revealed no significant effect on body weight and weights of vital organs of rats. A significant decrease in the testicular levels of 17-beta hydroxysteroid dehydrogenase and increase in total soluble proteins was observed in rats treated with 0.02 and 0.03% quinestrol. The plasma levels of lipid peroxidation in the form of malondialdehyde concentration and lactate dehydrogenase increased significantly whereas the level of testosterone decreased significantly in treated rats. The plasma levels of acid and alkaline phosphatases, superoxide dismutase and total proteins differed non-significantly among rats of treated and untreated groups. The effect was found reversed partially in rats autopsied after 60 days of treatment withdrawal. No micronuclei in bone marrow cells, no aberrations in chromosomes and no DNA damage in blood cells during comet assay indicated no genotoxic effect of quinestrol on B. bengalensis at the test doses administered. The results thus revealed that quinestrol causes reversible toxic effects in the form of oxidative stress, increased lytic enzyme activity and decreased steroidogenesis which may further lead to testicular damage thereby inhibiting reproductive function. Also more effect was shown at higher doses ingested in no-choice test as compared to low doses ingested in bi-choice tests.


Assuntos
Murinae , Quinestrol , Animais , Peso Corporal , Estrogênios , Masculino , Ratos , Testículo
14.
Pestic Biochem Physiol ; 165: 104549, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359540

RESUMO

This study proposes a biochemical and molecular model for the interaction between the Drosophila suzukii type 1 tyramine receptor (DsTAR1) and monoterpenes. A preliminary molecular and functional characterization of DsTAR1 cDNA revealed that a 1.8 kb long ORF codes for a 600 amino acid polypeptide featuring seven transmembrane domains, as expected for a GPCR. A stable HEK 293 cell line expressing DsTAR1 was tested for responsiveness to tyramine (TA) and octopamine (OA). In intracellular calcium mobilization studies, TA led to a concentration-dependent increase in [Ca2+]i (pEC50 ~ 6.40), completely abolished by pre-incubation with the antagonist yohimbine 1 µM. Besides, in dynamic mass redistribution (DMR) studies, TA evoked a positive DMR signal in a concentration-dependent manner (pEC50 ~ 6.80). The recombinant cell line was then used to test three monoterpenes (thymol, carvacrol and α-terpineol) as putative ligands for DsTAR1. The terpenoids showed no agonist effects in both DMR and calcium mobilization assays, but they increased the potency of the endogenous ligand, TA, acting as positive allosteric modulators. Moreover, expression analysis on adults D. suzukii, exposed for 24, 72 or 120 h to a sublethal concentration of the three monoterpenes, showed a downregulation of DsTAR1. This evidence has led to hypothesize that the downregulation of DsTAR1 might be a compensatory mechanism in response to the positive allosteric modulation of the receptor induced by monoterpenes. Therefore, these findings might be useful for the development of a new generation of biopesticides against Drosophila suzukii, targeting TAR1.


Assuntos
Agentes de Controle Biológico , Drosophila , Animais , Células HEK293 , Humanos , Monoterpenos , Receptores de Amina Biogênica
15.
Pestic Biochem Physiol ; 165: 104563, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359542

RESUMO

Bradysia odoriphaga is a destructive insect pest, damaging more than 30 crop species. Nicotinic acetylcholine receptors (nAChRs) mediating fast excitatory transmission in the central nervous system in insects are the molecular targets of some economically important insecticides including imidacloprid, which has been widely used to control B. odoriphaga in China since 2013. However, the clear characterization about nAChRs in B. odoriphaga is still unknown. Hence, our objective is to identify and characterize the nAChR gene family in B. odoriphaga based on the transcriptome database and sequence, phylogenetic and expression profiles analysis. In this study, we cloned seven nAChR subunit genes from B. odoriphaga, including Boα1, Boα2, Boα3, Boα7, Boα8, Boß1 and Boß3. Sequence analysis revealed that the seven nAChR subunits of B. odoriphaga shared the typical structural features with Drosophila melanogaster nAChR α1 subunit, including an extracellular N-terminal domain containing six functional loops (loop A-F), a signature Cys-loop with two disulfide bond-forming cysteines separated by 13 amino acid residues, and four typical transmembrane helices (TM1-TM4) in the C-terminal region. Phylogenetic analysis suggested that seven nAChR subunit genes in B. odoriphaga are evolutionarily conserved among four model insects, including D. melanogaster, Bombyx mori, Apis mellifera and Tribolium castaneum. Meanwhile, nAChR α4, α5, α6 and ß2 subunit genes may potentially exist in B. odoriphaga, which need further study. Furthermore, quantitative real-time PCR analysis revealed the specific expression pattern of nAChR subunits in three body parts including head, thorax and abdomen, and developmental expression pattern of nAChR subunits throughout the B. odoriphaga life cycle. These results provided necessary information for further investigating the diverse functions of nAChRs in B. odoriphaga.


Assuntos
Drosophila melanogaster , Receptores Nicotínicos , Sequência de Aminoácidos , Animais , Abelhas , China , Filogenia
16.
Pestic Biochem Physiol ; 165: 104555, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359544

RESUMO

The development of genetic based techniques, specifically RNA interference (RNAi), has emerged as a powerful tool in novel pest management strategies for pestiferous coleoptera. The 28-spotted ladybird beetle, Henosepilachna vigintioctopunctata, is a dynamic foliar pest of solenaceous plants, primarily potato plants, and has quickly become one of the most important pests attacking many crops in Asian countries. In this study, we demonstrate the efficacy of dietary RNAi targeting vATPase B, which led to significant gene silencing. Downstream effects of vATPase B silencing appeared to be both time- and partial dose-dependent. Our results indicate that silencing of vATPase B caused a significant decrease in survival rate, as well as reduced the food stuffs consumption and inhibited the overall development of H. vigintioctopunctata. Furthermore, results demonstrate expression of insect melanism related genes, TH and DDC, was significantly up regulated under the dsvATPase B (RNAi molecule designed against vATPase B) treatment. The impact of oral dsvATPase B delivery on the survival of 1st, 3rd instars, and adults was investigated through bacterially expressed dsRNA. The effectiveness of RNAi-based gene silencing in H. vigintioctopunctata provides a powerful reverse genetic tool for the functional annotation of its genes. This study demonstrates that vATPase B may represent a candidate gene for RNAi-based control of H. vigintioctopunctata.


Assuntos
Besouros , RNA de Cadeia Dupla , Animais , Dieta , Controle de Pragas , Interferência de RNA
17.
Pestic Biochem Physiol ; 165: 104554, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359545

RESUMO

Dinotefuran (DTF) is a systemic neonicotinoid insecticide characterized by a tetrahydrofuran ring. In the present study, we examined the characteristics of DTF binding to native nicotinic acetylcholine receptors (nAChRs) expressed in the American cockroach Periplaneta americana using radioligand-binding methods. The Scatchard analysis, using [3H]imidacloprid (IMI), indicated that IMI has a single class of high-affinity binding sites in the P. americana nerve cord. In contrast, the Scatchard analysis using [3H]DTF indicated that DTF has two different classes of binding sites. Both DTF and IMI were found to bind to one of the classes, for which DTF showed low affinity. The other class, for which DTF showed high affinity, was localized in the abdominal nerve cord but not in the thoracic nerve cord. IMI showed low affinity for the high-affinity DTF binding sites. Our data suggest that DTF binds with high affinity to a nAChR subtype distinct from the high-affinity subtype for IMI. This difference might be responsible, at least in part, for the difference in resistance development to DTF and IMI in P. americana.


Assuntos
Baratas , Inseticidas , Periplaneta , Receptores Nicotínicos , Animais , Sítios de Ligação , Guanidinas , Neonicotinoides , Nitrocompostos
18.
Pestic Biochem Physiol ; 165: 104464, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359546

RESUMO

The glutathione S-transferases (GSTs) are enzymes involved in several distinct biological processes. In insects, the GSTs, especially delta and epsilon classes, play a key role in the metabolism of xenobiotics used to control insect populations. Here, we investigated its potential role in temephos resistance, examining the GSTE2 gene from susceptible (RecL) and resistant (RecR) strains of the mosquito Aedes aegypti, vector for several pathogenic arboviruses. Total GST enzymatic activity and the GSTE2 gene expression profile were evaluated, with the GSTE2 cDNA and genomic loci sequenced from both strains. Recombinant GSTE2 and mutants were produced in a heterologous expression system and assayed for enzyme kinetic parameters. These proteins also had their 3D structure predicted through molecular modeling. Our results showed that RecR has a profile of total GST enzymatic activity higher than RecL, with the expression of the GSTE2 gene in resistant larvae increasing six folds. Four exclusive RecR mutations were observed (L111S, I150V, E178A and A198E), which were absent in the laboratory susceptible strains. The enzymatic activity of the recombinant GSTE2 showed different kinetic parameters, with the GSTE2 RecR showing an enhanced ability to metabolize its substrate. The I150V mutation was shown to induce significant changes in catalytic parameters and a 3D modeling of GSTE2 mapped two of the RecR changes (L111S and I150V) near the enzyme's catalytic pocket, also implying an impact on its catalytic activity. Our results reinforce a potential role for GSTE2 in the metabolic resistance phenotype while contributing to the understanding of the molecular basis for the resistance mechanism.


Assuntos
Aedes , Inseticidas , Animais , Resistência a Inseticidas , Mosquitos Vetores , Temefós
19.
Pestic Biochem Physiol ; 165: 104467, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359547

RESUMO

RNA interference (RNAi) has proven to be a very promising prospect for insect pest control. However, low RNAi efficacy limits further development of this biotechnology for use on lepidopteran insects, including the rice striped stem borer (SSB) (Chilo suppressalis), one of the major destructive rice pests. In this work, the application of various nanoparticles (NPs) by which double-stranded RNA (dsRNA) could be encapsulated was evaluated as an alternative delivery strategy to potentially increase the bioactivity of dsRNA. Three NPs, chitosan, carbon quantum dot (CQD), and lipofectamine2000, complexed with dsRNA (to target the glyceraldehyde-3-phosphate dehydrogenase gene (G3PDH)) were tested to examine their use in controlling SSB. Relative mRNA expressions were quantified using qPCR to evaluate knockdown efficiency of NP-dsRNA treated larvae, and the correlated dsRNA-mediated SSB larval mortality was tested. Thereafter, the content dynamics of hemolymph dsRNA after ingesting different NP-dsRNA were monitored in vivo; the hemolymph dsRNA content was in ratios of 5.67, 9.43, and 1 with chitosan, CQD, and lipofectamine2000 induced samples, respectively. The results demonstrated that all three tested NPs led to efficient feeding delivery by improving both dsRNA stability and cellular uptake equally. Furthermore, there was a strong correlation (r= 0.9854) between the hemolymph dsRNA contents and the average RNAi depletions in the non-gut tissues of SSB. Overall, our results strongly suggest that due to its strong endosomal escaping ability, CQD was the most efficient carrier for inducing systemic RNAi, and thereby causing effective gene silencing and mortality in SSB.


Assuntos
Mariposas , Nanopartículas , Animais , Larva , Interferência de RNA , RNA de Cadeia Dupla
20.
Pestic Biochem Physiol ; 165: 104550, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359548

RESUMO

The two-spotted spider mite, Tetranychus urticae, is a polyphagous pest feeding on over 1100 plant species, including numerous highly valued economic crops. The control of T. urticae largely depends on the use of acaricides, which leads to pervasive development of acaricide resistance. Cytochrome P450-mediated metabolic detoxification is one of the major mechanisms of acaricide resistance in T. urticae. NADPH-cytochrome P450 reductase (CPR) plays as a crucial co-factor protein that donates electron(s) to microsomal cytochrome P450s to complete their catalytic cycle. This study seeks to understand the involvement of CPR/P450 in acaricide resistance in T. urticae. The full-length cDNA sequence of T. urticae's CPR (TuCPR) was cloned and characterized. TuCPR was ubiquitously transcribed in different life stages of T. urticae and the highest transcription was observed in the nymph and adult stages. TuCPR was constitutively over-expressed in six acaricide resistant populations compared to a susceptible one. TuCPR transcriptional expression was also induced by multiple acaricides in a time-dependent manner. Down-regulation of TuCPR via RNA interference (RNAi) in T. urticae led to reduced enzymatic activities of TuCPR and cytochrome P450s, as well as a reduction of resistance to multiple acaricides, abamectin, bifenthrin, and fenpyroximate. The outcome of this study highlights CPR as a potential novel target for eco-friendly control of T. urticae and other related plant-feeding pests.


Assuntos
Acaricidas , Tetranychidae , Animais , Sistema Enzimático do Citocromo P-450 , NADPH-Ferri-Hemoproteína Redutase , Interferência de RNA
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