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51.
Ghazaryan N. Movsisyan N. Macedo J. C. Vaz S. Ayvazyan N. Pardo L. Logarinho E. 《Molecular Biology》2021,55(3):405-412
Molecular Biology - Macrovipera lebetina obtusa (MLO) is a venomous snake endemic to Middle East. Here we describe the therapeutic potential of the MLO snake venom. In S-180 sarcoma-bearing mouse... 相似文献
52.
Joost Groot Yizhou Zhou Eric Marshall Patrick Cullen Thomas Carlile Dongdong Lin Chong-Feng Xu Justin Crisafulli Chao Sun Fergal Casey Baohong Zhang Christina Alves 《Biotechnology journal》2021,16(8):2000548
In recent years, High-Throughput Sequencing (HTS) based methods to detect mutations in biotherapeutic transgene products have become a key quality step deployed during the development of manufacturing cell line clones. Previously we reported on a higher throughput, rapid mutation detection method based on amplicon sequencing (targeting transgene RNA) and detailed its implementation to facilitate cell line clone selection. By gaining experience with our assay in a diverse set of cell line development programs, we improved the computational analysis as well as experimental protocols. Here we report on these improvements as well as on a comprehensive benchmarking of our assay. We evaluated assay performance by mixing amplicon samples of a verified mutated antibody clone with a non-mutated antibody clone to generate spike-in mutations from ∼60% down to ∼0.3% frequencies. We subsequently tested the effect of 16 different sample and HTS library preparation protocols on the assay's ability to quantify mutations and on the occurrence of false-positive background error mutations (artifacts). Our evaluation confirmed assay robustness, established a high confidence limit of detection of ∼0.6%, and identified protocols that reduce error levels thereby significantly reducing a source of false positives that bottlenecked the identification of low-level true mutations. 相似文献
53.
Liliane Bezerra de Lima Wliana Alves Viturino da Silva Ewelyn Cintya Felipe dos Santos Janaína Carla Barbosa Machado Thamara Figueiredo Procópio Maiara Celine de Moura Thiago Henrique Napoleão Magda Rhayanny Assunção Ferreira Luiz Alberto Lira Soares 《化学与生物多样性》2021,18(12):e2100538
The aim of this study was to evaluate the phytochemical composition, antioxidant, and antimicrobial potential of crude extract and fractions of Punica granatum leaves. The extract was produced by turbo extraction, after which hexanic, ethyl acetate, and aqueous fractions were obtained by partitioning. The chemical analyses were performed by thin layer chromatography and high-performance liquid chromatography, and the antioxidant activities were assayed by DPPH. and ABTS.+. Minimal inhibitory and bactericidal concentrations (MIC/MBC) were applied to twenty-two bacteria. Most strains susceptible to extract/fractions and resistant to antibiotics were selected, and ampicillin, azithromycin, ciprofloxacin, and gentamicin were associated with the ethyl acetate fraction (EAF) against multidrug-resistant strains in modulatory and checkboard models. The data from chromatographic analyses showed flavonoids and tannins in the extract, as well as the enrichment of EAF in phenols, mainly flavonoids. The flavonoids were connected to the electron transfer activity demonstrated in the DPPH. and ABTS.+ assays. Gram-positive strains are more susceptible to EAF. The subinhibitory concentrations of P. granatum enhanced the antimicrobial activity of the agents and reduced the EAF individual MIC, and the combination of EAF and antibiotics demonstrated a synergistic effect. These results present a promising approach for developing a therapy in which antioxidant extracts and fractions can be used in combination with antibiotics. 相似文献
54.
Lara Soares Aleixo de Carvalho Lívia Mara Silva Vinícius Carius de Souza Marcos Paulo Nascimento da Silva Priscila V. S. Z. Capriles Priscila de Faria Pinto Josué de Moraes Ademar Alves Da Silva Filho 《化学与生物多样性》2021,18(11):e2100604
Schistosomiasis, a neglected tropical disease caused by Schistosoma species, harms over 250 million people in several countries. The treatment is achieved with only one drug, praziquantel. Cardamonin, a natural chalcone with in vitro schistosomicidal activity, has not been in vivo evaluated against Schistosoma. In this work, we evaluated the in vivo schistosomicidal activities of cardamonin against Schistosoma mansoni worms and conducted enzymatic apyrase inhibition assay, as well as molecular docking analysis of cardamonin against potato apyrase, S. mansoni NTPDase 1 and S. mansoni NTPDase 2. In a mouse model of schistosomiasis, the oral treatment with cardamonin (400 mg/kg) showed efficacy against S. mansoni, decreasing the total worm load in 46.8 % and reducing in 54.5 % the number of eggs in mice. Cardamonin achieved a significant inhibition of the apyrase activity and the three-dimensional structure of the potato apyrase, obtained by homology modeling, showed that cardamonin may interact mainly through hydrogen bonds. Molecular docking studies corroborate with the action of cardamonin in binding and inhibiting both potato apyrase and S. mansoni NTPDases. 相似文献
55.
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
56.
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
57.
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
58.
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
59.
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
60.
Characterization of Indoor Environmental Quality in Primary Schools in Maia: A Portuguese Case Study
Scientific evidence associates indoor environment pollutants with respiratory effects (asthma and allergies), and children constitute one of most sensitive groups. Indoor air quality (IAQ) in schools may indeed be a significant health factor for children, with effects on school attendance and performance. Our aim was to characterize IAQ of classrooms in Maia County (north of Portugal) for which there was no information available. The study was conducted in 21 of the 40 primary schools, selected by stratified random sampling. Depending on the dimension, one or two classrooms were tested at each school. Walkthrough surveys of school grounds, buildings, and individual classrooms were done. Continuous measurements were taken of temperature, relative humidity, airborne respirable particles, total volatile organic compounds, and carbon dioxide, whereas bioaerosols were counted on Plate Count Agar during regular school activities. The indoor arithmetic mean for PM10, CO2, TCOV, and bioaerosol concentrations were 0.14 mg/m3, 999 ppm, 0.41 mg/m3, and 4140 UCF/m3, respectively. The values of PM10 and CO2 were close to their acceptable maximum values, but bioaerosols were much higher. This study supports previous studies conducted in school environments and emphasizes the need for proactive indoor air quality audits in school buildings. 相似文献