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1.
Naturwissenschaften ; 109(2): 17, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35138481

RESUMO

Climate change mediated by anthropogenic activity induces significant alterations on pest abundance and behavior and a potential increase in the use of agrochemicals for crop protection. Pesticides have been a tool in the control of pests, diseases, and weeds of agricultural systems. However, little attention has been given to their toxic effects on beneficial insect communities that contribute to the maintenance and sustainability of agroecosystems. In addition to pesticide-induced direct mortality, their sublethal effects on arthropod physiology and behavior must be considered for a complete analysis of their impact. This review describes the sublethal effects of pesticides on agriculturally beneficial insects and provides new information about the impacts on the behavior and physiology of these insects. The different types of sublethal effects of pesticides used in agriculture on pollinators, predators, parasitoids, and coprophagous insects were detailed.


Assuntos
Artrópodes , Praguicidas , Agricultura , Animais , Insetos , Praguicidas/toxicidade
2.
J Cell Physiol ; 236(5): 3599-3614, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33044004

RESUMO

TRPV4 is a nonselective cationic channel responsive to several physical and chemical stimuli. Defects in TRPV4 channel function result in human diseases, such as skeletal dysplasias, arthropathies, and peripheral neuropathies. Nonetheless, little is known about the role of TRPV4 in other cellular functions, such as nuclear Ca2+ homeostasis or Ca2+ -regulated transcription. Here, we confirmed the presence of the full-length TRPV4 channel in the nuclei of nonpolarized Madin-Darby canine kidney cells. Confocal Ca2+ imaging showed that activation of the channel increases cytoplasmic and nuclear Ca2+ leading to translocation of TRPV4 out of the nucleus together with ß-catenin, a transcriptional regulator in the Wnt signaling pathway fundamental in embryogenesis, organogenesis, and cellular homeostasis. TRPV4 inhibits ß-catenin transcriptional activity through a direct interaction dependent upon channel activity. This interaction also occurs in undifferentiated osteoblastoma and neuroblastoma cell models. Our results suggest a mechanism in which TRPV4 may regulate differentiation in several cellular contexts.


Assuntos
Cálcio/metabolismo , Núcleo Celular/metabolismo , Células Epiteliais/metabolismo , Rim/citologia , Modelos Biológicos , Canais de Cátion TRPV/metabolismo , Transcrição Gênica , beta Catenina/genética , Animais , Sinalização do Cálcio , Diferenciação Celular , Linhagem Celular Tumoral , Cães , Humanos , Ativação do Canal Iônico , Células Madin Darby de Rim Canino , Neuroblastoma/patologia , Osteossarcoma/patologia , Ligação Proteica , Domínios Proteicos , Transporte Proteico , Canais de Cátion TRPV/química , beta Catenina/metabolismo
3.
Circ Res ; 122(7): e49-e61, 2018 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-29467196

RESUMO

RATIONALE: The MR (mineralocorticoid receptor) antagonists belong to the current therapeutic armamentarium for the management of cardiovascular diseases, but the mechanisms conferring their beneficial effects are poorly understood. Part of the cardiovascular effects of MR is because of the regulation of L-type Cav1.2 Ca2+ channel expression, which is generated by tissue-specific alternative promoters as a long cardiac or short vascular N-terminal transcripts. OBJECTIVE: To analyze the molecular mechanisms by which aldosterone, through MR, modulates Cav1.2 expression and function in a tissue-specific manner. METHODS AND RESULTS: In primary cultures of neonatal rat ventricular myocytes, aldosterone exposure for 24 hours increased in a concentration-dependent manner long cardiac Cav1.2 N-terminal transcripts expression at both mRNA and protein levels, correlating with enhanced concentration-, time-, and MR-dependent P1-promoter activity. In silico analysis and mutagenesis identified MR interaction with both specific activating and repressing DNA-binding elements on the P1-promoter. The relevance of this regulation is confirmed both ex and in vivo in transgenic mice harboring the luciferase reporter gene under the control of the cardiac P1-promoter. Moreover, we show that this cis-regulatory mechanism is not limited to the heart. Indeed, in smooth muscle cells from different vascular beds, in which the short vascular Cav1.2 N-terminal transcripts is normally the major isoform, we found that MR signaling activates long cardiac Cav1.2 N-terminal transcripts expression through P1-promoter activation, leading to vascular contractile dysfunction. These results were further corroborated in hypertensive aldosterone/salt rodent models, showing notably a positive correlation between blood pressure and cardiac P1-promoter activity in aorta. This new vascular long cardiac Cav1.2 N-terminal transcripts molecular signature reduced sensitivity to the Ca2+ channel blocker, nifedipine, in aldosterone-treated vessels. CONCLUSIONS: Our results reveal that MR acts as a transcription factor to translate aldosterone signal into specific cardiac P1-promoter activation that might influence the therapeutic outcome of cardiovascular diseases.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Miócitos Cardíacos/metabolismo , Regiões Promotoras Genéticas , Receptores de Mineralocorticoides/metabolismo , Ativação Transcricional , Aldosterona/farmacologia , Animais , Canais de Cálcio Tipo L/genética , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Ratos , Ratos Wistar
4.
Ecotoxicol Environ Saf ; 189: 109978, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761554

RESUMO

The endoparasitoid wasp Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae) is used to control defoliating lepidopteran pests. Chemical insecticides are not compatible with natural enemies, but bioinsecticides, such as Bacillus thuringiensis Berliner (Bt), have great potential for use in integrated pest management. However, interactions between Bt and P. elaeisis still need to be investigated. This study aimed to evaluate the effects of Bt on parental and first-generation P. elaeisis parasitizing Bt-susceptible and -resistant Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). An additional aim was to determine the toxicity of Bt to susceptible third-instar S. frugiperda larvae. Larvae were exposed to lethal concentrations (LC50 and LC90) of Bt and then allowed to be parasitized by P. elaeisis. Parasitoid longevity, immature production, reproductive performance, and behavioral responses were evaluated. Bt repelled P. elaeisis and reduced immature production. Parental and first filial generation parasitoids of both sexes emerged from Bt-treated larvae showed lower survivorship than controls. Parasitoids had poorer reproductive performance in Bt-susceptible and -resistant pupae than in untreated pupae. Palmistichus elaeisis emerged from Bt-susceptible and -resistant S. frugiperda showed altered host-searching behavior and reproductive parameters, which indicates low compatibility between the bioinsecticide agent and the parasitoid wasp.


Assuntos
Bacillus thuringiensis/fisiologia , Himenópteros/fisiologia , Inseticidas/efeitos adversos , Controle Biológico de Vetores/métodos , Animais , Feminino , Inseticidas/farmacologia , Larva/fisiologia , Longevidade/efeitos dos fármacos , Masculino , Pupa/microbiologia , Pupa/parasitologia , Reprodução/efeitos dos fármacos , Spodoptera/microbiologia , Spodoptera/parasitologia
5.
Int J Mol Sci ; 21(22)2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33238586

RESUMO

Risk of cardiovascular disease (CVD) increases considerably as renal function declines in chronic kidney disease (CKD). Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) has emerged as a novel innate immune receptor involved in both CVD and CKD. Following activation, NOD1 undergoes a conformational change that allows the activation of the receptor-interacting serine/threonine protein kinase 2 (RIP2), promoting an inflammatory response. We evaluated whether the genetic deficiency of Nod1 or Rip2 in mice could prevent cardiac Ca2+ mishandling induced by sixth nephrectomy (Nx), a model of CKD. We examined intracellular Ca2+ dynamics in cardiomyocytes from Wild-type (Wt), Nod1-/- and Rip2-/- sham-operated or nephrectomized mice. Compared with Wt cardiomyocytes, Wt-Nx cells showed an impairment in the properties and kinetics of the intracellular Ca2+ transients, a reduction in both cell shortening and sarcoplasmic reticulum Ca2+ load, together with an increase in diastolic Ca2+ leak. Cardiomyocytes from Nod1-/--Nx and Rip2-/--Nx mice showed a significant amelioration in Ca2+ mishandling without modifying the kidney impairment induced by Nx. In conclusion, Nod1 and Rip2 deficiency prevents the intracellular Ca2+ mishandling induced by experimental CKD, unveiling new innate immune targets for the development of innovative therapeutic strategies to reduce cardiac complications in patients with CKD.


Assuntos
Rim/metabolismo , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/genética , Insuficiência Renal Crônica/genética , Animais , Cálcio/metabolismo , Sinalização do Cálcio/genética , Modelos Animais de Doenças , Humanos , Rim/patologia , Camundongos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , NF-kappa B/genética , Proteína Adaptadora de Sinalização NOD1/ultraestrutura , Conformação Proteica , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/ultraestrutura , Insuficiência Renal Crônica/patologia , Retículo Sarcoplasmático/genética , Retículo Sarcoplasmático/patologia
6.
Ecotoxicol Environ Saf ; 167: 69-75, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30296698

RESUMO

The selectivity of insecticides on natural enemies in pest control are an important strategy for Integrated Pest Management. However, insecticides can have side effects on non-target organisms such as natural enemies. This study evaluated the histological and cytological changes mediated by the sublethal concentration of the imidacloprid insecticide on the midgut of non-target predator Podisus nigrispinus (Heteroptera: Pentatomidae), used in the biological control of pests. Imidacloprid was toxic for P. nigrispinus with LC50 = 3.75 mg L-1 and survival of 51.8%. This sublethal concentration of imidacloprid causes histological alterations in the midgut epithelium and cytotoxic features were irregular border epithelium, cytoplasmic vacuolation, and apocrine secretions in the first 6 h after exposure with the insecticide. Apoptosis in the digestive cells occurs after 12 h of exposure in the midgut. These results suggest that imidacloprid may affect the digestive physiology of P. nigrispinus and compromise the effective predation of this insect a biological control agent. The associated use of this insecticide with the predator in pest control should be carefully evaluated.


Assuntos
Trato Gastrointestinal/efeitos dos fármacos , Heterópteros/efeitos dos fármacos , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Animais , Agentes de Controle Biológico , Trato Gastrointestinal/metabolismo , Heterópteros/metabolismo , Dose Letal Mediana , Comportamento Predatório/efeitos dos fármacos , Testes de Toxicidade
7.
Ecotoxicol Environ Saf ; 172: 53-58, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30682633

RESUMO

Hypothenemus hampei Ferrari (Coleoptera: Curculionidae) is the main pest of coffee crops, and effective methods for pest management are needed urgently. Bioassays were conducted to assess the effects of the insecticide chlorantraniliprole on H. hampei adults. Toxicity, survivorship, larval production, respiration rate, and behavioral responses to six concentrations of chlorantraniliprole were evaluated. Chlorantraniliprole was toxic to H. hampei (LD50 = 0.49 mg mL-1 and LD90 = 1.21 mg mL-1). Survivorship was 98% in adults not exposed to chlorantraniliprole, decreasing to 52% in insects exposed to LD50 and 2% in insects treated with LD90. H. hampei showed reduced mobility on insecticide-treated surfaces. The insecticide promoted a decrease in the respiration rate of H. hampei for up to 3 h after exposure, altering behavioral responses and locomotor activity. Chlorantraniliprole was shown to have lethal and sublethal effects on H. hampei and, thus, can be used rotationally in integrated pest management programs to control of this pest in coffee crops and retard of insect resistance.


Assuntos
Besouros/efeitos dos fármacos , Inseticidas , Controle Biológico de Vetores/métodos , ortoaminobenzoatos , Animais , Coffea , Besouros/fisiologia , Frutas , Larva/efeitos dos fármacos , Larva/fisiologia , Testes de Toxicidade
8.
Rev Invest Clin ; 71(4): 226-236, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31448784

RESUMO

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a potentially lethal disease, whose characteristic ventricular tachycardias are adrenergic-dependent. Although rare, CPVT should be considered in the differential diagnosis of young individuals with exercise-induced syncope. Mutations in five different genes (RYR2, CASQ2, CALM1, TRDN, and TECRL) are associated with the CPVT phenotype, although RYR2 missense mutations are implicated in up to 60 % of all CPVT cases. Genetic testing has an essential role in the diagnosis, management, pre-symptomatic diagnosis, counseling, and treatment of the proband; furthermore, genetic information can be useful for offspring and relatives. By expert consensus, CPVT gene testing is a Class I recommendation for patients with suspected CPVT. Beta-adrenergic and calcium-channel blockers are the cornerstones of treatment due to the catecholaminergic dependence of the arrhythmias. Unresponsive patients are treated with an implantable cardioverter-defibrillator to reduce the risk of sudden cardiac death. In the present article, a brief review of the genetic and molecular mechanisms of this intriguing disease is provided.


Assuntos
Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Taquicardia Ventricular/diagnóstico , Diagnóstico Diferencial , Testes Genéticos , Humanos , Mutação , Síncope/diagnóstico , Taquicardia Ventricular/genética , Taquicardia Ventricular/terapia
9.
Ecotoxicol Environ Saf ; 156: 263-270, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29554611

RESUMO

This study evaluated toxic effects, repellency and respiration rate caused by terpenoid constituents of cinnamon and clove essential oils and against Sitophilus granarius L. (Coleoptera: Curculionidae). The lethal concentrations (LC50 and LC90), repellent effect, and behavior repellency response on adults of S. granarius after exposure to six concentrations of each essential oil and terpenoids were evaluated. The chemical composition of the cinnamon oil was also determined and primary compounds were eugenol (10.5%), trans-3-caren-2-ol (10.2%), benzyl benzoate (9.99%), caryophyllene (9.34%), eugenyl acetate (7.71%), α-phellandrene (7.41%), and α-pinene (7.14%). In clove essential oil, the primary compounds were eugenol (27.1%), caryophyllene (24.5%), caryophyllene oxide (18.3%), 2-propenoic acid (12.2%), α-humulene (10.8%), γ-cadinene (5.01%), and humulene oxide (4.84%). Cinnamon and clove essential oil was toxic to S. granarius. In toxic terpenoids compounds, eugenol has stronger contact toxicity in S. granarius than caryophyllene oxide, followed by α-pinene, α-humulene, and α-phellandrene. Insects reduced their respiratory rates after being exposed to essential oil terpenoids and avoided or reduced their mobility on terpenoid-treated surfaces. Cinnamon and clove essential oil, and their terpenoid constituents were toxic and repellent to adult S. granarius and, therefore, have the potential to prevent or retard the development of insecticide resistance.


Assuntos
Cinnamomum zeylanicum/toxicidade , Óleo de Cravo/toxicidade , Óleos Voláteis/toxicidade , Syzygium/toxicidade , Gorgulhos/efeitos dos fármacos , Animais , Cinnamomum zeylanicum/química , Óleo de Cravo/química , Inseticidas , Óleos Voláteis/química , Controle de Pragas/métodos , Syzygium/química
10.
Ecotoxicol Environ Saf ; 156: 1-8, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29524778

RESUMO

Annonaceous acetogenins (Annona squamosa Linnaeus) comprises of a series of natural products which are extracted from Annonaceae species, squamocin proved to be highly efficient among those agents. Squamocin is mostly referred as a lethal agent for midgut cells of different insects, with toxic effects when tested against larva of some insects. In present study, LC50 and LC90 of squamocin for A. gemmatalis Hübner (Lepidoptera: Noctuidae) were calculated using probit analysis. Morphological changes in midgut cells were analyzed under light, fluorescence and transmission electron microscopes when larvae were treated with LC50 and LC90 of squamocin for 24, 48 and 72 h. Results revealed that the maximum damage to midgut cells was found under LC90 where it showed digestive cells with enlarged basal labyrinth, highly vacuolated cytoplasm, damaged apical surface, cell protrusions to the gut lumen, autophagy and cell death. The midgut goblet cells showed a strong disorganization of their microvilli. Likewise, in insects treated with squamocin, mitochondria were not marked with Mitotracker fluorescent probe, suggesting some molecular damage in these organelles, which was reinforced by decrease in the respiration rate in these insects. These results demonstrate that squamocin has potential to induce enough morphological changes in midgut through epithelial cell damage in A. gemmatalis.


Assuntos
Furanos/toxicidade , Lactonas/toxicidade , Lepidópteros/efeitos dos fármacos , Animais , Autofagia , Sistema Digestório/anatomia & histologia , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/ultraestrutura , Larva/anatomia & histologia , Larva/efeitos dos fármacos , Larva/ultraestrutura , Lepidópteros/anatomia & histologia , Lepidópteros/crescimento & desenvolvimento , Lepidópteros/ultraestrutura
11.
An Acad Bras Cienc ; 90(4): 3541-3549, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30184013

RESUMO

The sweet potato is an alternative energy source, but its sustainability depends on efficient water use. The objective of this study was to evaluate sweet potato morpho-physiological characteristics, and water use efficiency (WUE). Irrigation depths of 50, 75, 100, and 125% of crop evapotranspiration (ETc) were applied. The morpho-physiological indicators, WUE, leaf area index (LAI), leaf water potential, leaf temperature, and leaf chlorophyll index (ICF), were evaluated. The WUE of the sweet potato cultivars increased until the 75% water depth of the ETc. The LAI of these cultivars increased with irrigation depth, with higher values at 100% of the ETc. The leaf water potential of the two sweet potato cultivars was lowest with the lower irrigation depth. Leaf temperature was closer to that of ambient temperatures in treatments with greater irrigation depth. The increase of the WUE with the greater accumulation of dry biomass is due to greater CO2 diffusion by stomata. The reduction in the growth of these plants is due to water stress limiting stomatal conductance, transpiration, leaf growth (LAI) and chlorophyll concentration, proportional to soil moisture conditions. The functional relationship between soil moisture and growth is essential to optimize irrigation management at different growth stages.


Assuntos
Irrigação Agrícola/métodos , Ipomoea batatas/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Estômatos de Plantas/fisiologia
12.
J Cell Physiol ; 232(7): 1794-1807, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27869310

RESUMO

TRPV4 (transient receptor potential vanilloid 4) is a cation channel activated by hypotonicity, moderate heat, or shear stress. We describe the expression of TRPV4 during the differentiation of a corneal epithelial cell model, RCE1(5T5) cells. TRPV4 is a late differentiation feature that is concentrated in the apical membrane of the outmost cell layer of the stratified epithelia. Ca2+ imaging experiments showed that TRPV4 activation with GSK1016790A produced an influx of calcium that was blunted by the specific TRPV4 blocker RN-1734. We analyzed the involvement of TRPV4 in RCE1(5T5) epithelial differentiation by measuring the development of transepithelial electrical resistance (TER) as an indicator of the tight junction (TJ) assembly. We showed that TRPV4 activity was necessary to establish the TJ. In differentiated epithelia, activation of TRPV4 increases the TER and the accumulation of claudin-4 in cell-cell contacts. Epidermal Growth Factor (EGF) up-regulates the TER of corneal epithelial cultures, and we show here that TRPV4 activation mimicked this EGF effect. Conversely, TRPV4 inhibition or knock down by specific shRNA prevented the increase in TER. Moreover, TRPP2, an EGF-activated channel that forms heteromeric complexes with TRPV4, is also concentrated in the outmost cell layer of differentiated RCE1(5T5) sheets. This suggests that the EGF regulation of the TJ may involve a heterotetrameric TRPV4-TRPP2 channel. These results demonstrated TRPV4 activity was necessary for the correct establishment of TJ in corneal epithelia and as well as the regulation of both the barrier function of TJ and its ability to respond to EGF. J. Cell. Physiol. 232: 1794-1807, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Diferenciação Celular , Epitélio Corneano/citologia , Modelos Biológicos , Canais de Cátion TRPV/metabolismo , Junções Íntimas/metabolismo , Células 3T3 , Animais , Cálcio/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Claudina-4/metabolismo , Impedância Elétrica , Fator de Crescimento Epidérmico/farmacologia , Ativação do Canal Iônico/efeitos dos fármacos , Camundongos , Transporte Proteico/efeitos dos fármacos , Coelhos , Frações Subcelulares/metabolismo , Junções Íntimas/efeitos dos fármacos , Fatores de Tempo
13.
J Econ Entomol ; 109(2): 962-5, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26791821

RESUMO

Rhynchophorus palmarum (L.) causes great losses to the oil palm plantations, and therefore, the spatial and temporal distribution of this insect should be studied, to manage its populations. Insect sampling was done for 2 yr in an oil palm plantation from Colombia. In total, 60 pheromone traps were used in healthy palm trees and infected ones with the Bud Rot disease. On the other hand, developmental stages of this insect were quantified on healthy and diseased palms for two consecutive years. Number of adult R. palmarum per sampling was higher in the plantation with diseased palm trees, 3.85 and 74.7 insects per trap, than in those with healthy ones, 1.91 and 9.48 insects per trap, in the first and second years, respectively. After the integration of pheromone traps, there was a significant increase in the infestation level at all stages of development of the insect. For the first time, the presence of R. palmarum attracted to diseased palms is reported. The association between R. palmarum and the Bud Rot disease is a cause of death and great loss to the oil palm plantations.


Assuntos
Arecaceae/microbiologia , Arecaceae/parasitologia , Besouros/fisiologia , Interações Hospedeiro-Parasita , Phytophthora/fisiologia , Animais , Doenças das Plantas , Crescimento Demográfico
14.
Microsc Microanal ; 21(6): 1514-1522, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26601683

RESUMO

Podisus distinctus (Hemiptera: Pentatomidae) is a zoophytophagous insect with significant potential for use as a biological control agent in agriculture and forestry because their nymphs and adults actively prey on diverse insect species. The saliva of this insect possesses active substances that cause paralysis and death of the prey. As the first step in identifying compounds of P. distinctus saliva, this study describes the ultrastructure of the salivary glands of this predator. The salivary system of P. distinctus possesses a pair of main salivary glands with a short anterior lobe, a long posterior lobe, and a pair of tubular accessory glands. The main salivary gland of P. distinctus has no associated muscles, suggesting that the saliva-release mechanism occurs with the help of certain thorax muscles. The main salivary gland epithelium has a single layer of cells (varying from cubical to columnar) with cytoplasm rich in rough endoplasmic reticulum, spherical granules of different sizes, a nucleus with a predominance of decondensed chromatin, and nucleolus. The apical cell region has a few short microvilli and the basal region has plasma membrane infoldings. The epithelium of the accessory salivary glands possesses a single-layered epithelium of cubic cells delimiting a narrow lumen. The apical cell region has a high density of microvilli and pleomorphic mitochondria, whereas the central cell region is rich in rough endoplasmic reticulum with a well-developed nucleus and decondensed chromatin. The basal cell region is characterized by the presence of several basal plasma membrane infoldings associated with mitochondria and numerous openings to the hemocoel forming large channels. The ultrastructural characteristics suggest that the main salivary glands and accessory salivary glands play a vital role in protein synthesis for saliva production and that the accessory glands are involved in transport of materials of the hemolymph.

15.
J Insect Sci ; 152015.
Artigo em Inglês | MEDLINE | ID: mdl-25843587

RESUMO

Demotispa neivai Bondar (Coleoptera: Chrysomelidae) damage oil palm fruits, which makes it necessary to develop products to control this insect. The mortality, repellency, and antifeeding effects on adults of D. neivai of six plant extracts of Azadirachta indica A. Juss. (Sapindales: Meliaceae), Ricinus communis (L.) (Malpighiaes: Euphorbiaceae), Citrus sinensis Oesbek (Sapindales: Rutaceae), Nicotiana tabacum (L.) (Slanales: Solanaceae), Capsicum annuum (L.) (Solanales: Solanaceae), and Artemisia absinthium (L.) (Asterales: Asteraceae) were determined: 1) the lethal concentration LC50-90, lethal time of D. neivai was evaluated after spraying the fruits of oil palm; 2) repellent effects of each ingredient were evaluated by calculating the index of repellency; 3) antifeeding effects with the rate of inhibition calculated between doses of 20 and 24 g/liter. The mortality of D. neivai was higher with the extracts Ci. sinensis, R. communis, N. tabacum, and Ca. annuum. The mortality of D. neivai increased in the first 72 hr in all treatments. The extracts of N. tabacum, Ca. annuum, and A. indica were more repellent to D. neivai that those of Ci. sinensis, Ar. Absinthium, and R. communis. Antifeeding effect was higher with Ci. sinensis and R. communis. The increased mortality of D. neivai by Ci. sinensis can be explained by the effect of this compound on the respiratory system of insects. Extracts of Ci. sinensis, R. communis, N. tabacum, and Ca. annuum repelled and caused mortality of D. neivai and, thus, can be used in integrate pest management programs of this pest in oil palm plantations.


Assuntos
Besouros , Controle de Insetos , Inseticidas , Extratos Vegetais , Animais , Feminino , Magnoliopsida/química , Masculino
16.
Artigo em Inglês | MEDLINE | ID: mdl-38913262

RESUMO

The caterpillar Anticarsia gemmatalis (Lepidoptera: Noctuidae) is a prevalent pest in soybean plantations, managed using both natural and synthetic chemical products. However, the emergence of resistance in some populations emphasizes the need to explore alternative insecticides. Flupyradifurone, a neurotoxic insecticide, has not been previously used for controlling A. gemmatalis. This study evaluated the potential of flupyradifurone in the management of A. gemmatalis. Initially, the toxicity and anti-feeding effects, as well as histopathological and cytotoxic impacts, of flupyradifurone on A. gemmatalis were evaluated. Subsequently, the indirect effects of flupyradifurone on the midgut and fat body of the predator Podisus nigrispinus (Hemiptera: Pentatomidae) were verified. The results indicate the susceptibility of caterpillars to flupyradifurone, with an LC50 of 5.10 g L-1. Furthermore, the insecticide adversely affects survival, induces an anti-feeding response, and inflicts damage on the midgut of the caterpillars. However, flupyradifurone also leads to side effects in the predator P. nigrispinus through indirect intoxication of the caterpillars, including midgut and fat body damage. While flupyradifurone demonstrates toxicity to A. gemmatalis, suggesting its potential for the chemical control of this pest, the indirect negative effects on the predator indicate the need for its controlled use in integrated pest management programs with the insecticide and the predator.

17.
Front Physiol ; 13: 834220, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360237

RESUMO

In mesenteric arteries (MAs), aldosterone (ALDO) binds to the endogenous mineralocorticoid receptor (MR) and increases the expression of the voltage-gated L-type Cav1.2 channel, an essential ion channel for vascular contraction, sarcoplasmic reticulum (SR) Ca2+ store refilling, and Ca2+ spark generation. In mesenteric artery smooth muscle cells (MASMCs), Ca2+ influx through Cav1.2 is the indirect mechanism for triggering Ca2+ sparks. This process is facilitated by plasma membrane-sarcoplasmic reticulum (PM-SR) nanojunctions that drive Ca2+ from the extracellular space into the SR via Sarco/Endoplasmic Reticulum Ca2+ (SERCA) pump. Ca2+ sparks produced by clusters of Ryanodine receptors (RyRs) at PM-SR nanodomains, decrease contractility by activating large-conductance Ca2+-activated K+ channels (BKCa channels), which generate spontaneous transient outward currents (STOCs). Altogether, Cav1.2, SERCA pump, RyRs, and BKCa channels work as a functional unit at the PM-SR nanodomain, regulating intracellular Ca2+ and vascular function. However, the effect of the ALDO/MR signaling pathway on this functional unit has not been completely explored. Our results show that short-term exposure to ALDO (10 nM, 24 h) increased the expression of Cav1.2 in rat MAs. The depolarization-induced Ca2+ entry increased SR Ca2+ load, and the frequencies of both Ca2+ sparks and STOCs, while [Ca2+]cyt and vasoconstriction remained unaltered in Aldo-treated MAs. ALDO treatment significantly increased the mRNA and protein expression levels of the SERCA pump, which counterbalanced the augmented Cav1.2-mediated Ca2+ influx at the PM-SR nanodomain, increasing SR Ca2+ content, Ca2+ spark and STOC frequencies, and opposing to hyperpolarization-induced vasoconstriction while enhancing Acetylcholine-mediated vasorelaxation. This work provides novel evidence for short-term ALDO-induced upregulation of the functional unit comprising Cav1.2, SERCA2 pump, RyRs, and BKCa channels; in which the SERCA pump buffers ALDO-induced upregulation of Ca2+ entry at the superficial SR-PM nanodomain of MASMCs, preventing ALDO-triggered depolarization-induced vasoconstriction and enhancing vasodilation. Pathological conditions that lead to SERCA pump downregulation, for instance, chronic exposure to ALDO, might favor the development of ALDO/MR-mediated augmented vasoconstriction of mesenteric arteries.

18.
Pest Manag Sci ; 78(1): 126-133, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34453875

RESUMO

BACKGROUND: The potential of Beauveria bassiana and Metarhizium anisopliae isolates obtained from naturally infected oil palm pests was evaluated to control Demotispa neivai as an alternative for organophosphate insecticide use in oil palm crops in Latin America. Two B. bassiana (Bb-0018 and Bb-0025) and two M. anisopliae (Ma-0002 and Ma-0003) isolates were tested against D. neivai adults for hydrophobicity, virulence, survival, adhesion to host cuticle, and mortality in semi-field conditions. RESULTS: Concentration-mortality bioassays demonstrate that isolates had lethal effect on D. neivai adults with Bb-0025 [median lethal concentration (LC50 ) = 3.45 × 107 conidia mL-1 ] and Bb-0018 (LC50  = 3.75 × 107 conidia mL-1 ) being the most effective followed by Ma-0003 (LC50  = 3.38 × 108 conidia mL-1 ) and Ma-0002 (5.33 × 108 conidia mL-1 ). Adult survival was 99% without exposure to fungal isolates, decreasing to 21.65% in insects exposed to Ma-0002, 19.41% with Ma-0003, 20.13% with Bb-0018, and 0.17% with Bb-0025. Mortality of D. neivai adults caused by the entomopathogenic fungal isolates was similar in both laboratory and semi-field conditions. Also, vegetative growth of the entomopathogenic fungal isolates was found in infected D. neivai adults in the field. CONCLUSION: Our data suggest that the tested entomopathogenic fungal isolates are effective against D. neivai with potential to be used as biological control agents contributing to the decrease of the use of chemical insecticides to control this oil palm pest. © 2021 Society of Chemical Industry.


Assuntos
Beauveria , Besouros , Metarhizium , Animais , Controle Biológico de Vetores , Esporos Fúngicos
19.
Environ Sci Pollut Res Int ; 29(20): 29967-29975, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34997483

RESUMO

Forestry pest management includes biological and chemical methods of pest control. Using insecticides and natural enemies can be compatible in forest pest management programs. The compatibility of the predatory stink bug Podisus distinctus with the insecticide indoxacarb, used in forestry, needs to be evaluated in Brazil. This study investigated the mortality, survival, respiration, preference, prey consumption, and locomotor activity of P. distinctus adults exposed to indoxacarb. In concentration-mortality bioassays, the lethality of indoxacarb (LC50 = 2.62 g L-1 and LC90 = 6.11 g L-1) was confirmed in P. distinctus adults. The survival rate was 100% in predator insects not exposed to indoxacarb, declining to 40.7% in predator insects exposed to 2.62 g L-1 and 0.1% in predators treated with 6.11 g L-1. Indoxacarb reduced the respiration of P. distinctus from 18.45 to 14.41 µL CO2 h-1 at 2.62 g L-1 for up to 3 h after insecticide exposure, inhibiting food consumption and displaying hyperexcitation. The harmful effects of indoxacarb to the natural enemy suggest that it should be better assessed for use with P. distinctus for pest management in forestry.


Assuntos
Hemípteros , Heterópteros , Inseticidas , Animais , Inseticidas/farmacologia , Oxazinas/farmacologia , Comportamento Predatório
20.
Turk J Urol ; 48(5): 331-338, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36197140

RESUMO

OBJECTIVE: To evaluate the impact on continence rate during 1-year follow-up of a preservation technique that included nonligation of the dorsal vascular complex and sparing of the puboprostatic ligaments and the endopelvic fascia during laparoscopic radical prostatectomy. MATERIAL AND METHODS: Information from 30 patients who underwent the preservation technique was prospectively collected and compared with data from 60 patients who underwent the nonpreservation traditional technique. A single surgeon performed all procedures. RESULTS: Demographic and preoperative characteristics were similar. The mean patient age was 59 years in both groups. All patients were stage cT1c or cT2. Operative time was significantly lower in the preservation technique group (229.6 vs. 262.7 minutes, P < .001). There were no significant differences in intraoperative bleeding, discharge hemoglobin level, blood transfusion rate, length of hospitalization, and drop in the hemoglobin level. The probability of continence recovery was significantly higher in the preservation technique group than in the traditional technique group (hazard ratio = 0.50, 95% CI = 0.31-0.81). The continence rate (0 pads/day) for the preservation technique group versus the traditional technique group at 1, 3, 6, and 12 months was, respectively, 53.3% versus 30% (P = .031), 90% versus 45% (P < .001), 90% versus 63.3% (P = .008), and 96.6% versus 78.3% (P = .024). There were no significant differences between the groups regarding potency and oncologic outcomes. CONCLUSION: Nonligation of the dorsal vascular complex and preservation of the puboprostatic ligaments and the endopelvic fascia improved urinary continence compared with the traditional nonpreservation technique, with no impact in terms of bleeding and oncologic outcomes.

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