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51.
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
52.
Henrique Barbosa Thais A. Costa-Silva Geanne A. Alves Conserva Adelson J. Araujo Ana Luísa L. Lordello Guilherme M. Antar Maiara Amaral Marisi G. Soares Andre G. Tempone João Henrique G. Lago 《化学与生物多样性》2021,18(4):e2001022
One new aporphine, dicentrine-β-N-oxide ( 1 ), together with five related known alkaloids dehydrodicentrine ( 2 ), predicentrine ( 3 ), N-methyllaurotetanine ( 4 ), cassythicine ( 5 ), and dicentrine ( 6 ) were isolated from the leaves of Ocotea puberula (Lauraceae). Antiprotozoal activity of the isolated compounds was evaluated in vitro against trypomastigote forms of Trypanosoma cruzi. Among the tested compounds, alkaloid 1 exhibited higher potential with EC50 value of 18.2 μM and reduced toxicity against NCTC cells (CC50>200 μM – SI>11.0), similar to positive control benznidazole (EC50 of 17.7 μM and SI=10.7). Considering the promising results of dicentrine-β-N-oxide ( 1 ) against trypomastigotes, the mechanism of parasite death caused by this alkaloid was investigated. As observed, this compound reached the plasma membrane electric potential directly after 2 h of incubation and triggered mitochondrial depolarization, which probably leads to trypomastigote death. Therefore, dicentrine-β-N-oxide ( 1 ), reported for the first time in this work, can contribute to future works for the development of new trypanocidal agents. 相似文献
53.
Mariem Khouja Rita C. Alves Diana Melo Anabela S. G. Costa M. Antonia Nunes Abdelhamid Khaldi M. Beatriz P. P. Oliveira Chokri Messaoud 《化学与生物多样性》2021,18(6):e2100071
The lipid fraction of seeds from different pine species and populations was studied regarding total lipid content, fatty acid profile and vitamin E composition. The investigated seeds contained a high percentage of lipid (13.6 to 31.5 %). Lipid fractions were found to be rich in vitamin E, which varied significantly among species and populations. P. halepensis (Ph−Hn) showed the highest content of vitamin E (256.3 mg/kg of seeds) and the uppermost content of α-tocopherol (44 mg/kg). However, P. halepensis (Ph−Kas) was the richest in γ-tocopherol (204.9 mg/kg). Lipid fractions had a low content of δ-tocopherol (1.2 to 3.6 mg/kg. The highest content of γ-tocotrienol (∼18 %) was determined for P. halepensis (Ph−Dc and Ph−Hn). Thirteen fatty acids were identified by GC-FID with significant variation between the investigated species. The linoleic acid was the major fatty acid followed by oleic acid and palmitic acid. The chemical differentiation among species for the composition of fatty acids and vitamin E was confirmed by PCA. Significant correlations were observed between the content of vitamin E and fatty acids and ecological parameters of P. halepensis populations. 相似文献
54.
Claudio Marcos Bedran Magalhães Renan Alves Resende Renata Noce Kirkwood 《Journal of electromyography and kinesiology》2013,23(5):1243-1249
The purpose of this study was to identify the gait strategies in women with mild and moderate knee osteoarthritis (OA). Forty women diagnosed with OA of the knee and 40 healthy women participated in the study. Toe-out progression angle, trunk lateral lean, hip internal abduction moment and gait speed were measured using Qualisys ProReflex System and two force plates. Principal component analysis was applied to extract features from the gait waveforms data that characterized the waveforms main modes of temporal variation. Discriminant analysis with a stepwise model was conducted to determine which strategies could best discriminate groups. According to the discriminant model, the PC2 of the internal abduction moment of the hip and the gait speed were the most discriminatory variables between the groups. The OA group showed decreased gait speed, decreased hip internal abduction moment during the loading response phase, and increased hip internal abduction moment during the mid and terminal stance phases. Interventions that may increase hip internal abduction moment, such as the strengthening of the hip abductors muscles, may benefit women with knee OA. Training slower than normal gait speeds must be considered in light of potential adverse implications on overall physical function, daily tasks, and safety. 相似文献
55.
J. Paulo Macedo Jorge Pereira João Faria J. Luis Alves José López-López 《Computer methods in biomechanics and biomedical engineering》2013,16(12):655-662
AbstractObjectives: The purpose of the present study was to evaluate the distribution and magnitude of stresses through the bone tissue surrounding Morse taper dental implants at different positioning relative to the bone crest. Materials and Methods: A mandibular bone model was obtained from a computed tomography scan. A three-dimensional (3D) model of Morse taper implant-abutment systems placed at the bone crest (equicrestal) and 2?mm bellow the bone crest (subcrestal) were assessed by finite element analysis (FEA). FEA was carried out on axial and oblique (45°) loading at 150 N relatively to the central axis of the implant. The von Mises stresses were analysed considering magnitude and volume of affected peri-implant bone. Results: On vertical loading, maximum von Mises stresses were recorded at 6-7?MPa for trabecular bone while values ranging from 73 up to 118?MPa were recorded for cortical bone. On oblique loading at the equiquestral or subcrestal positioning, the maximum von Mises stresses ranged from 15 to 21?MPa for trabecular bone while values at 150?MPa were recorded for the cortical bone. On vertical loading, >99.9vol.% cortical bone volume was subjected to a maximum of 2?MPa while von Mises stress values at 15?MPa were recorded for trabecular bone. On oblique loading, >99.9vol.% trabecular bone volume was subjected to maximum stress values at 5?MPa, while von Mises stress values at 35?MPa were recorded for >99.4vol.% cortical bone. Conclusions: Bone volume-based stress analysis revealed that most of the bone volume (>99% by vol) was subjected to significantly lower stress values around Morse taper implants placed at equicrestal or subcrestal positioning. Such analysis is commentary to the ordinary biomechanical assessment of dental implants concerning the stress distribution through peri-implant sites. 相似文献
56.
Régis A. Zanette Laerte Ferreiro Sydney H. Alves Francielli P.K. Jesus Claudia Lautert Andréia Spanamberg Janio M. Santurio 《Revista iberoamericana de micología》2013,30(4):264-266
BackgroundPythium insidiosum is an oomycete classified in the kingdom Stramenopila. P. insidiosum hyphae are not able to initiate infection without the secretion of hydrolytic enzymes, which are considered an important factor in microbial virulence.AimsTo evaluate the extracellular enzymatic activity of 14 Brazilian P. insidiosum isolates and a standard strain (ATCC 58637) by the API-ZYM System screening method.MethodsZoospores were grown in RPMI 1640 broth, and 65 μL of the liquid phase were inoculated in each cupule of the API-ZYM strips.ResultsDifferences in the enzymatic activities were observed among the isolates, although phosphohydrolases and ester hydrolases were conspicuous among all isolates. β-glucosidase was also present in most of the isolates. Enzymatic activities of α-glucosidase and chymotrypsin were not observed, differing from a previous study involving Australian isolates and intracellular enzymes.ConclusionsThe discrepancy in the enzymatic profile observed among Brazilian P. insidiosum isolates reflects the phenotypic variations found in susceptibility tests. 相似文献
57.
In vivo effects of two sublethal doses of chlorpyrifos and carbaryl were studied in Procambarus clarkii after 2 and 7 days of exposure, and after pesticide removal. Chlorpyrifos inhibited carboxylesterase activity in a concentration-dependent manner, but acetylcholinesterase was less sensitive. Compared with chlorpyrifos, carbaryl had a less marked effect on esterase activity. The effects of selected pesticides on biotransformation or oxidative stress biomarkers were contradictory. Chlorpyrifos lowered ethoxyresorufin-O-deethylase (EROD), catalase and oxidized glutathione (GSSG) levels but raised glutathione-S-transferase activity, while carbaryl raised EROD, catalase and glutathione-S-transferase, but lowered glutathione peroxidase and reduced glutathione (GSH) levels. The effects on protein expression patterns depending on pesticide type and the tissue used for analysis were studied in parallel by 2-DE. In gill and nervous tissue about 2000 spots (pI 4–7) were resolved, with quite different expression patterns. Chlorpyrifos altered 72 proteins, mostly in nervous tissue, and carbaryl 35, distributed evenly between organs. Several specific spots were selected as specific protein expression signatures for chlorpyrifos or carbaryl exposure in gills and nervous tissue, respectively. 相似文献
58.
Leandro Luiz Borges Fernanda Abreu Santana Isabel Samila Lima Castro Klever Márcio Antunes Arruda Humberto Josué de Oliveira Ramos Maurilio Alves Moreira Everaldo Gonçalves de Barros 《Molecular breeding : new strategies in plant improvement》2013,32(4):933-942
The common bean (Phaseolus vulgaris L.) is the main source of protein and an important source of minerals in several countries around the world. Angular leaf spot, caused by the fungus Pseudocercospora griseola, is one of the major diseases of the common bean. In this work, we used two-dimensional gel electrophoresis and mass spectrometry to analyze alterations in the proteome of common bean leaves challenged with an incompatible race of P. griseola. Twenty-three differentially expressed proteins were detected in leaves of cultivar AND 277 collected at 12, 24 and 48 h after inoculation. The proteins were digested with trypsin and submitted to MALDI-TOF/TOF and MicrOTOF-Q electrospray mass spectrometry. Nineteen of them were identified upon MS/MS fragmentation. Most of these proteins are involved with amino acid metabolism, terpenoid metabolism, phenylpropanoid biosynthesis, antioxidant systems, vitamin and cofactor metabolism, plant–pathogen interaction, carbohydrate metabolism, photosynthesis, or genetic information processing, showing that the interaction in this pathosystem affects different genes from various metabolic pathways and processes. 相似文献
59.
Lilian Da-Croce Greicy Helen Ribeiro Gambarini-Paiva Patrícia Caroline Angelo Eduardo Alves Bambirra Antônio Carlos Vieira Cabral Ana Lúcia Brunialti Godard 《Cell and tissue banking》2013,14(1):65-76
The tissue cryopreservation maintains the cellular metabolism in a quiescence state and makes the conservation possible for an indefinite period of time. The choice of an appropriate cryopreservation protocol is essential for maintenance of cryopreserved tissue banks. This study evaluated 10 samples of umbilical cord, from which small fragments of tissue (Wharton’s jelly and cord lining membrane) were subjected to two protocols of cryopreservation: slow cooling and vitrification. The samples were frozen for a period of time ranging from 5 to 78 days. The efficiency of cryopreservation was evaluated by testing cell viability, histological analysis, cell culture, cytogenetic analysis and comparison with the results of the fresh samples. The results showed that the slow cooling protocol was more efficient than the vitrification for cryopreservation of umbilical cord tissue, because it has caused fewer changes in the structure of tissue (edema and degeneration of the epithelium) and, despite the significant decrease cell viability compared to fresh samples, the ability of cell proliferation in vitro was preserved in most samples. In conclusion, this study showed that it is possible to cryopreserve small fragments of tissue from the umbilical cord and, to obtain viable cells capable of proliferation in vitro after thawing, contributing to the creation of a frozen tissue bank. 相似文献
60.
Karina Motta Melo Ingrid Reale Alves Julio Cesar Pieczarka José Augusto de Oliveira David Cleusa Yoshiko Nagamachi Cesar Koppe Grisolia 《Genetics and molecular biology》2013,36(3):425-429
The frequency of spontaneous micronucleus (MN) formation in fish species needs to be determined to evaluate their usefulness for genotoxic biomonitoring. The definition of a good bioindicator takes into account the current knowledge of its metabolic traits as well as other factors including its feeding behavior and relationship to the environment. In this study, we compared the basal frequencies of micronucleated erythrocytes and nuclear abnormalities (NA) among different species of the fish Order Gymnotiformes (Rhamphichthys marmoratus, Steatogenys elegans, Sternopygus macrurus, Parapteronotus hasemani, Gymnotus mamiraua, Gymnotus arapaima, Brachyhypopomus beebei, Brachyhypopomus n. sp. BENN) sampled in several localities of the Eastern Amazon. A baseline of MN and NA frequency in these fish was determined, enabling the identification of potentially useful species as models for genotoxicity studies. Only one impacted sample collected at a site in the River Caripetuba showed a significant number of NAs, which may be due to the release of wastewater by neighbouring mining industries and by the burnt fuel released by the small boats used by a local community. Our results may provide support for further studies in areas of the Eastern Amazon affected by mining, deforestation and other anthropogenic activities. 相似文献