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Item Post-embryonic development of intramandibular glands of Friesella schrottkyi (Friese, 1900) (Hymenoptera: Apidae) workers(Papéis Avulsos de Zoologia, 2017) Oliveira, André Henrique de; Lisboa, Luciane Cristina de Oliveira; Serrão, José Eduardo; Zanuncio, José Cola; Souza, Edmilson Amaral deExocrine glands play important role in social organization of insects, such as caste and inter-caste differentiation. Due their functional and structural plasticity, morphological studies on such glands contribute to better understanding the biology of social bees. Therefore, the aim of the study was to characterize the sequence of the post-embryonic development of intramandibular glands of Friesella schrottkyi (Friese, 1900) (Hymenoptera: Apidae) workers using histological and histochemical analyses. The mandibles of pupae at different developmental stages and newly emerged adults were analyzed. The intramandibular glands of F. schrottkyi presented two types: class I glands, in the mandible epidermis and class III glands, inside the mandible cavity that open onto external surface. The intramandibular glands of F. schrottkyi developed during the transition from the prepupae to the white-eyed pupae, as shown by the morphological changes. Black-eyed pupae of F. schrottkyi presented fully developed intramandibular glands.Item Exposure to insecticides reduces populations of Rhynchophorus palmarum in oil palm plantations with bud rot disease(Insects, 2019-04) Martínez, Luis Carlos; Plata-Rueda, Angelica; Rodríguez-Dimaté, Francisco Andrés; Campos, Juliana Mendonça; Santos Júnior, Valdeir Celestino dos; Rolim, Gabriela Da Silva; Fernandes, Flavio Lemes; Silva, Wiane Meloni; Wilcken, Carlos Frederico; Zanuncio, José Cola; Serrão, José EduardoThe South American palm weevil (SAPW), Rhynchophorus palmarum Linnaeus (Coleoptera: Curculionidae) is the main pest of Elaeis guineensis and damages palm trees with bud rot disease in the Americas. The effects of six neurotoxic insecticides (abamectin, carbaryl, deltamethrin, fipronil, imidacloprid and spinosad) were evaluated against SAPW for toxicity, survival, reproduction, and mortality. Abamectin (LC50 = 0.33 mg mL−1 ), Carbaryl (LC50 = 0.24 mg mL−1 ), deltamethrin (LC50 = 0.17 mg mL−1 ), and fipronil (LC50 = 0.42 mg mL−1 ) were the most toxic to SAPW. Adult survival was 95% without exposure to insecticides, decreasing to 78–65% in insects treated with the LC25 and 49–35% in insects exposed to LC50 . Sublethal doses of carbaryl, fipronil and imidacloprid showed significant effect on the reproduction of this insect. Mortality of SAPW populations caused by insecticides had similar effects in the laboratory and field conditions. The results suggest that carbaryl, deltamethrin, fipronil, and imidacloprid caused significantly higher mortality as compared to the control in SAPW and may be used to control its populations in oil palm trees where bud rot appears as the key disease for SAPW attraction and infestation.Item Histochemistry, immunohistochemistry and cytochemistry of the anterior midgut region of the stingless bee Melipona quadrifasciata and honey bee Apis mellifera (Hymenoptera: Apidae)(Micron, 2018-10) Carneiro, Lenise Silva; Gonçalves, Wagner Gonzaga; Fernandes, Kenner Morais; Zanuncio, José Cola; Serrão, José Eduardo; Teixeira, Stéphanie Asséf Millen ValenteThe anterior midgut region of stingless bees is anatomically differentiated with tall and narrow cells, whereas in other social and solitary bees this anatomical gut region is lacking. The objective of the present study was to describe the histochemistry, immunohistochemistry and cytochemistry of the anterior midgut region of the stingless bee Melipona quadrifasciata in comparison with the honey bee Apis mellifera. The anterior midgut region of both species was evaluated for identification of the enzymes β- galactosidase, glucose-6-phosphatase, acid phosphatase, and alkaline phosphatase, the membrane transporter aquaporin, the hormone FMRF-amide, and lysosomes. Histology of the anterior midgut region showed that this region in M. quadrifasciata workers did not present external folds of the wall, whereas the following midgut wall presented many. In A. mellifera, folds in the midgut wall occur starting from the fore- midgut transition region. Despite these morphological differences, the tests evaluated were similar in both species. β-galactosidase was not found in the anterior midgut cells. Glucose-6-phosphatase and acid phosphatase occurred in the apical region of the gut epithelium. Alkaline phosphatase occurred in vesicles in apical cytoplasm and in the basal plasma membrane infoldings of the epithelial cells. Aquaporin was found in the basal region of the midgut epithelium and in the associated visceral muscles. FMRF-amide was found only in nerve endings in the anterior midgut region. All cells in the anterior midgut region were rich in lysosomes. These results suggest that in both bee species, although they have anatomically different anterior midgut regions, these regions present high metabolic activity and function in cellular homeostasis, lipid absorption and are under neurohormone control.Item Squamocin induce histological and ultrastructural changes in the midgut cells of Anticarsia gemmatalis (Lepidoptera: Noctuidae)(Ecotoxicology and Environmental Safety, 2018-07-30) Fiaz, Muhammad; Martínez, Luis Carlos; Costa, Marilza da Silva; Cossolin, Jamile Fernanda Silva; Plata-Rueda, Angelica; Gonçalves, Wagner Gonzaga; Sant’Ana, Antônio Euzébio Goulart; Zanuncio, José Cola; Serrão, José EduardoAnnonaceous 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.Item Toxicological and morphological effects of tebufenozide on Anticarsia gemmatalis (Lepidoptera: Noctuidae) larvae(Chemosphere, 2018-12) Fiaz, Muhammad; Martínez, Luis Carlos; Plata-Rueda, Angelica; Gonçalves, Wagner Gonzaga; Shareef, Muhammad; Zanuncio, José Cola; Serrão, José EduardoThe velvetbean caterpillar, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), is an important soybean pest in the Americas. Tebufenozide, a novel nonsteroidal ecdysone agonist is used to control this pest. Bioassays were conducted to assess tebufenozide toxicity and their ultrastructural effects on midgut of A. gemmatalis. The toxicity, survivorship, behavior response, and respiration rate for A. gemmatalis larvae after exposure to tebufenozide were evaluated. Also, A. gemmatalis larvae were treated with LC50 obtained from tebufenozide and changes were observed on their midgut cells after 24, 48 and 96 h. Tebufenozide was toxic to A. gemmatalis (LC50 = 3.86 mg mL−1 and LC90 = 12.16 mg mL−1) and survivorship was 95% for adults that had not been exposed to tebufenozide, decreasing to 52% with LC50 and 27% with LC90 estimated value. Damage to midgut cells was increased with exposure time. These cells show damaged striated border with release of protrusions to the midgut lumen, damaged nuclear membrane and nucleus with condensed chromatin and increase in amount of autophagic vacuoles. Mitochondria were modified into nanotunnels which might be an evidence that tebufenozide induces damage to cells, resulting in cell death, proved by immunofluorescence analyses. This insecticide also caused paralysis movement with change in homeostasis and compromised larval respiration. Thus, sublethal exposure to tebufenozide is sufficient to disturb the ultrastructure of A. gemmatalis midgut, which might compromise insect fitness, confirming tebufenozide a possible controlling insecticide.Item Toxicity and cytotoxicity of the insecticide imidacloprid in the midgut of the predatory bug, Podisus nigrispinus(Ecotoxicology and Environmental Safety, 2019-01-15) Martínez, Luis Carlos; Plata-Rueda, Angelica; Gonçalves, Wagner Gonzaga; Freire, André Filipe Penha Aires; Zanuncio, José Cola; Bozdoğan, Hakan; Serrão, José EduardoThe 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.Item Ultrastructure and cytochemistry of salivary glands of the predator Podisus nigrispinus (Hemiptera: Pentatomidae)(Protoplasma, 2014-05) Martínez, Luis Carlos; Zanuncio, José Cola; Serrão, José Eduardo; Fialho, Maria do Carmo QueirozPodisus nigrispinus Dallas (Hemiptera: Pentatomidae) is a zoophytophagous insect with a potential for use as a biological control agent in agriculture because nymphs and adults actively prey on various insects by inserting mouthparts and regurgitating the contents of the salivary glands inside the prey, causing rapid paralysis and death. However, the substances found in saliva of P. nigrispinus that causes the death of the prey are unknown. As a first step to identify the component of the saliva of P. nigrispinus, this study evaluated the ultrastructure and cytochemistry of the salivary glands of P. nigrispinus. The salivary system of P. nigrispinus has a pair of principal salivary glands, which are bilobed with a short anterior lobe and a long posterior lobe, and a pair of tubular accessory glands. The principal gland epithelium is composed of a single layer of cells enclosing a large lumen. Epithelial cells of the principal salivary gland vary from cubic to columnar shape, with one or two spherical and well-developed nuclei. Cells of the anterior lobe of the principal salivary gland have an apical surface with narrow, short, and irregular plasma membrane foldings; apical and perinuclear cytoplasm rich in rough endoplasmic reticulum; and mitochondria with tubular cristae. The basal portion of the secretory cells has mitochondria associated with many basal plasma membrane infoldings that are short but form large extracellular canals. Secretory granules with electron-dense core and electron-transparent peripheral are dispersed throughout the cytoplasm. Cells of the posterior lobe of the principal salivary gland are similar to those of the anterior lobe, except for the presence of mitochondria with transverse cristae. The accessory salivary gland cells are columnar with apical microvilli, have well-developed nucleus and cytoplasm rich in rough endoplasmic reticulum, and have secretory granules. Cytochemical tests showed positive reactions for carbohydrate, protein, and acid phosphatase in different regions of the glandular system. The principal salivary glands of P. nigrispinus do not have muscle cells attached to its wall, suggesting that saliva-releasing mechanism may occurs with the participation of some thorax muscles. The cytochemical and ultrastructural features suggest that the principal and accessory salivary glands play a role in protein synthesis of the saliva.Item Ointment of Brassica oleracea var. capitata matures the extracellular matrix in skin wounds of Wistar rats(Evidence-Based Complementary and Alternative Medicine, 2015) Sarandy, Mariáurea Matias; Novaes, Rômulo Dias; Matta, Sérgio Luiz Pinto da; Mezencio, Jose Mario da Silveira; Silva, Marcelo Barreto da; Zanuncio, José Cola; Gonçalves, Reggiani VilelaWound healing is a complex process that aims to restore damaged tissue. Phytotherapeutics, such as cabbage, Brassica oleracea var. capitata (Brassicaceae), and sunflower, Helianthus annuus L. (Asteraceae) oil, are used as wound healers. Five circular wounds, each 12 mm in diameter, were made in the dorsolateral region of each rat. The animals were divided into four groups: balsam (B. oleracea); ointment (B. oleracea); sunflower oil (Helianthus annuus); control (saline solution 0.9%). These products were applied daily for 20 days and every four days the tissues of different wounds were removed. The wound contraction area, total collagen, types I and III collagen, glycosaminoglycans, and tissue cellularity were analyzed. In the groups that received ointment and balsam there was reduction in the wound area on days 4, 8, 12, and 20. Throughout the trial period, the balsam and ointment groups showed a higher amount of total collagen, type I collagen, and glycosaminoglycan compared to the others groups. The rats in the groups treated with B. oleracea var. capitata showed a higher number of cells on days 8, 16, and 20. B. oleracea was effective in stimulating the maturation of collagen and increasing the cellularity, as also in improving the mechanical resistance of the newly formed tissue.Item Vitellogenin transcytosis in follicular cells of the honeybee Apis mellifera and the wasp Polistes simillimus(Protoplasma, 2018-11) Dohanik, Virgínia Teles; Gonçalves, Wagner Gonzaga; Oliveira, Leandro Licursi; Zanuncio, José Cola; Serrão, José EduardoVitellogenin receptor (VgR) is a low-density lipoprotein receptor responsible for the mediated endocytosis of vitellogenin (Vg) during egg formation in insects. The maturing oocyte is enveloped by a follicular epithelium, which has large intercellular spaces during Vg accumulation (patency). However, Vg has been reported in the cytoplasm of follicular cells, indicating that there may be a transcellular route for its transport. This study verified the presence of VgR in the follicular cells of the ovaries of the honeybee Apis mellifera and the wasp Polistes simillimus in order to evaluate if Vg is transported via transcytosis in these insects. Antibodies specific for vitellogenin receptor (anti-VgR), vitellogenin (anti-Vg), and clathrin (anti-Clt) were used for immunolocalization. The results showed the presence of VgR on the apical and basal plasma membranes of follicular cells of the vitellogenic follicles in both species, indicating that VgR may have been transported from the basal to the apical cell domain, followed by its release into the perivitelline space, evidenced by the presence of apical plasma membrane projections containing VgR. Co-localization proved that Vg bind to VgR and that the transport of this protein is mediated by clathrin. These data suggest that, in these social insects, Vg is transported via clathrin-mediated VgR transcytosis in follicular cells.Item Diversity of Hemiptera (Arthropoda: Insecta) and their natural enemies on Caryocar brasiliense (Malpighiales: Caryocaraceae) trees in the Brazilian Cerrado(Florida Entomologist, 2016) Leite, Germano Leão Demolin; Veloso, Ronnie Von dos Santos; Zanuncio, José Cola; Alonso, Jatnel; Ferreira, Paulo Sérgio Fiuza; Almeida, Chrystian Iezid Maia; Fernandes, Geraldo Wilson; Serrão, José EduardoThe Cerrado occupies about 23% of the Brazilian territory and is characterized by great diversity of plants and insects and a great degree of endemism, and Caryocar brasiliense A. St.-Hil. (Malpighiales: Caryocaraceae) is widely distributed in this region. The diversity and abundance of hemipterans and their natural enemies were studied on trees of C. brasiliense in the Cerrado, pasture, and anthropic area in Montes Claros, Minas Gerais State, Brazil. We observed 1 rare, 8 common, and 1 frequent species of sucking insects; and 2 rare, 7 common, and 6 frequent species of natural enemies. Sucking insects and their natural enemies were most abundant in the pasture and least abundant in the Cerrado. Increasing diversity indices and numbers of species and individuals of sucking insects were followed by similar trends in the populations of natural enemies. Increasing populations of sucking insects led to greater numbers of individuals of ants, green lacewings, predator thrips, and ladybeetles. Aluminum level positively affected the number of species and individuals, and the pH of the soil reduced those of sucking insects. Leafhoppers had greater numbers on plants on soils with low pH values and high aluminum levels, but the opposite was noted for the aphids.