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81.
dos Santos Fernanda Marcelia Pflüger Pricila Fernandes Lazzarotto Leticia Uczay Mariana de Aguida Wesley Roberto da Silva Lisiane Santos Boaretto Fernanda Brião Menezes de Sousa Jayne Torres Picada Jaqueline Nascimento da Silva Torres Iraci Lucena Pereira Patrícia 《Neurochemical research》2021,46(8):2066-2078
Neurochemical Research - Gamma-decanolactone (GD) has been shown to reduce epileptic behavior in different models, inflammatory decreasing, oxidative stress, and genotoxic parameters. This study... 相似文献
82.
Rodrigues Augusto Pereira Fabrício F. Barbosa Paulo R.R. Silva-Torres Christian S.A. Torres Jorge B. 《Journal of Insect Behavior》2021,34(3):71-81
Journal of Insect Behavior - Control of the sugarcane borers, Diatraea saccharalis and Diatraea impersonatella (= D. flavipennella) (Lepidoptera: Crambidae), in Brazil, is based on mass release of... 相似文献
83.
84.
Alberto Cornejo Julio Caballero Mario Simirgiotis Vanessa Torres Luisa Snchez Nicols Díaz Marcela Guimaraes Marcos Hernndez Carlos Areche Sergio Alfaro Leonardo Caballero Francisco Melo 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):154
Parkinson''s disease (PD) is a neurodegenerative disorder that affects adult people whose treatment is palliative. Thus, we decided to test three dammarane triterpenes 1, 1a, 1b, and we determined that 1 and 1a inhibit β-aggregation through thioflavine T rather than 1b. Since compound 1 was most active, we determined the interaction between α-synuclein and 1 at 50 µM (Kd) through microscale thermophoresis. Also, we observed differences in height and diameter of aggregates, and α-synuclein remains unfolded in the presence of 1. Also, aggregates treated with 1 do not provoke neurites'' retraction in N2a cells previously induced by retinoic acid. Finally, we studied the potential sites of interaction between 1 with α-synuclein fibrils using molecular modelling. Docking experiments suggest that 1 preferably interact with the site 2 of α-synuclein through hydrogen bonds with residues Y39 and T44. 相似文献
85.
Daniel Silva Torres Bruna Alves de Oliveira Lígia Souza d Silveira Marcos Paulo da Silva Vinícius Rodrigues Durães Pereira Josué Moraes Mara Rúbia Costa Couri Rafaella Fortini Grenfell e Queiroz Patrícia Martins Parreiras Márcio Roberto Silva Lara Azevedo Alves Vinícius Carius de Souza Priscila Vanessa Zabala Capriles Goliatt Eveline Gomes Vasconcelos Ademar Alves da Silva Filho Priscila de Faria Pinto 《化学与生物多样性》2021,18(11):e2100439
In this work, two synthetic aurones revealed moderate schistosomicidal potential in in vitro and in vivo assays. Aurones ( 1 ) and ( 2 ) promoted changes in tegument integrity and motor activity, leading to death of adult Schistosoma mansoni worms in in vitro assays. When administered orally (two doses of 50 mg/kg) in experimentally infected animals, synthetic aurones ( 1 ) and ( 2 ) promoted reductions of 56.20 % and 57.61 % of the parasite load and stimulated the displacement towards the liver of the remaining adult worms. The oogram analysis revealed that the treatment with both aurones interferes with the egg development kinetics in the intestinal tissue. Seeking an action target for compounds ( 1 ) and ( 2 ), the connection with NTPDases enzymes, recognized as important therapeutic targets for S. mansoni, was evaluated. Molecular docking studies have shown promising results. The dataset reveals the anthelmintic character of these compounds, which can be used in the development of new therapies for schistosomiasis. 相似文献
86.
Vania Rebolledo María Carolina Otero Jos Manuel Delgado Fernando Torres Michelle Herrera Miguel Ríos Mauricio Cabaas Jos L. Martinez Mait Rodríguez-Díaz 《Saudi Journal of Biological Sciences》2021,28(1):1052
The Andean tree Schinus areira L. has multiple traditional uses, from the treatment of bronchitis and rheumatic diseases to menstrual cycle regulation and wound healing. With reported hypotensive, analgesic, antitumoral and anti-inflammatory properties, it acts predominantly against diseases related to oxidative stress. This study focuses on the antioxidant activity and phytochemical profile of the extracts of Schinus areira L.Serial extraction of the fruits was performed both by maceration and by Soxhlet. Total phenols and flavonoids were measured using the Folin-Ciocalteu method and AlCl3, respectively. In vitro antioxidant activity was determined by FRAP and DPPH.Results were similar for both extraction methods. Primary metabolites detected included carbohydrates, proteins and amino acids; secondary metabolites included tannins, flavonoids, saponins, steroids and triterpenes. Antioxidant activity was confirmed for ethyl acetate, methanolic and aqueous extracts. The methanolic extract had both the highest polyphenol content (>195 mg GAE/ g dry weight) and the highest antioxidant activity [EC50 > 476 μg/mL; >273 mg AA/g dry weight (DPPH); >301 mg AA/ g dry weight (FRAP)]. The extract does not produce macrophage cytotoxicity in RAW 264.7, which is indicated by an average cytotoxicity of 2% over 24 h.Our study serves as a starting point for future research on the pharmacological properties of Schinus areira L. 相似文献
87.
Agna R.S. Rodrigues Jorge B. Torres Herbert A.A. Siqueira Daniel P.A. Lacerda 《Biological Control》2013,64(3):217-224
Lambda-cyhalothrin is a pyrethroid insecticide widely used to control pests in various crop ecosystems, in which the lady beetle occurs naturally. Therefore, lady beetle populations are exposed to lambda-cyhalothrin sprays that may foster tolerance to this insecticide. This study was conducted to confirm the occurrence of resistance in the lady beetle Eriopis connexa (Germar) (Coleoptera: Coccinellidae) to lambda-cyhalothrin and to characterize the inheritance of resistance after eight progressive selection with insecticide dosages based on the LD50 determined for the F1 generation. Dose–mortality curves were determined for parental populations, F1 hybrids and backcross progenies. Parameters regarding the heritability of resistance to lambda-cyhalothrin in E. connexa allow estimating 10-fold increase in the initial LD50 after 54.5 generations of successive selections. The resistance of E. connexa to lambda-cyhalothrin was characterized as autosomally inherited and incompletely dominant, and influenced by a major gene with possible influence of secondary genes. Additionally, the resistance in E. connexa varies from functionally dominant to functionally recessive depending on the dose used. These findings indicate that insecticide resistance in E. connexa can be selected in the field as determined for field-collected individuals, and subsequently enhanced under laboratory conditions. Its characterization presented here is an important step toward linking biological and chemical control within pest management regarding the lady beetle and lambda-cyhalothrin targeting different pest groups. 相似文献
88.
89.
Griselda Torres Fernando Izquierdo Virginia Capó Ledy X. López María C. López Daniel Limonta Soledad Fenoy Carmen Del Águila Fernando J. Bornay-Llinares 《Revista iberoamericana de micología》2013,30(1):47-50
BackgroundMicrosporidiosis is a life threatening opportunistic infection of AIDS patients. The infection is usually restricted to specific anatomical areas, but could become systemic depending on the involved species. Genital microsporidiosis in female patients is rare.ObjectiveTo report genital microsporidiosis in female AIDS patients.MethodsTissues samples from the genital tract (ovary, fallopian tubes and uterus) of eight deceased women who died of wasting syndrome associated to AIDS and disseminated microsporidiosis at the Institute of Tropical Medicine Pedro Kourí were collected between 1997 and 2005. Using an indirect immunohistochemistry assay the microsporidia species involved in those cases were identified.ResultsWe report several cases of microsporidial infection of the female genital tract. Six out of eight women with the disseminated form of the disease showed the presence of microsporidia in the genital tract. Encephalitozoon cuniculi and Encephalitozoon hellem were identified in the internal lining epithelium of the fallopian tubes and endometrium.ConclusionsMicrosporidia species could disseminate to other organs and become systemic in severe immunocompromised cases. To our knowledge this is the greatest number of female genital tract microsporidiosis cases so far reported in humans. 相似文献
90.
Aspergillus fumigatus produces heavily melanized infectious conidia. The conidial melanin is associated with fungal virulence and resistance to various environmental stresses. This 1,8-dihydroxynaphthalene (DHN) melanin is synthesized by enzymes encoded in a gene cluster in A. fumigatus, including two laccases, Abr1 and Abr2. Although this gene cluster is not conserved in all aspergilli, laccases are critical for melanization in all species examined. Here we show that the expression of A. fumigatus laccases Abr1/2 is upregulated upon hyphal competency and drastically increased during conidiation. The Abr1 protein is localized at the surface of stalks and conidiophores, but not in young hyphae, consistent with the gene expression pattern and its predicted role. The induction of Abr1/2 upon hyphal competency is controlled by BrlA, the master regulator of conidiophore development, and is responsive to the copper level in the medium. We identified a developmentally regulated putative copper transporter, CtpA, and found that CtpA is critical for conidial melanization under copper-limiting conditions. Accordingly, disruption of CtpA enhanced the induction of abr1 and abr2, a response similar to that induced by copper starvation. Furthermore, nonpigmented ctpAΔ conidia elicited much stronger immune responses from the infected invertebrate host Galleria mellonella than the pigmented ctpAΔ or wild-type conidia. Such enhancement in eliciting Galleria immune responses was independent of the ctpAΔ conidial viability, as previously observed for the DHN melanin mutants. Taken together, our findings indicate that both copper homeostasis and developmental regulators control melanin biosynthesis, which affects conidial surface properties that shape the interaction between this pathogen and its host. 相似文献