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991.
Helton C. Silva Celso S. Nagano Luis A.G. Souza Kyria S. Nascimento Renato Isídro Plínio Delatorre Bruno Anderson M. Rocha Alexandre H. Sampaio Ana Maria S. Assreuy Alana F. Pires Luis Eduardo A. Damasceno Gabriela F.O. Marques-Domingos Benildo S. Cavada 《Process Biochemistry》2012,47(12):2347-2355
Vatairea guianensis seeds, a typical plant from the Brazilian Amazon region that belongs to the Dalbergieae tribe, possess a lectin that was isolated by precipitation with solid ammonium sulfate followed by guar gum affinity chromatography. This lectin was named VGL. The V. guianensis lectin strongly agglutinated rabbit erythrocytes and was inhibited by d-galactose and d-galactose-derived sugars, especially N-acetyl-d-galactosamine. VGL has been shown to be a stable protein, maintaining its hemagglutinating activity after incubation at a wide range of temperature and pH values and after incubation with ethylenediamine tetraacetic acid (EDTA). In a sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, the purified VGL exhibited an electrophoretic profile consisting of a major 30–32 kDa double band, which is termed the alpha-chain, and two minor components of 18 and 15 kDa, which are referred to as the beta- and gamma-chains, respectively. An analysis using electrospray ionization mass spectrometry also indicated that purified VGL contains a mixture of chains with molecular weights of 28,437 ± 2, 14,952 ± 2 and 12,332 ± 2. The complete amino acid sequence of VGL, as determined using tandem mass spectrometry, consists of 239 amino acid residues. VGL is a glycoprotein exhibiting high similarity in primary structure to other lectins from evolutionarily related plants, such as Vatairea macrocarpa lectin and lectins belonging to the Sophoreae tribe. VGL exhibits vasorelaxant activity in contracted rat aortas, an effect that is strictly dependent on the endothelium and involves nitric oxide and the lectin domain. 相似文献
992.
Tibana RA Prestes J Nascimento Dda C Martins OV De Santana FS Balsamo S 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(4):1027-1032
The aim of the present study was to compare the effect of 3 different rest intervals between sets on the total training volume, number of repetitions, ratings of perceived exertion (RPE), and resistance to fatigue in adolescents and adults during a resistance training session in the isoinertial chest press exercise. Fifteen male adolescents (15.2 ± 1.2 years; 20.7 ± 2.0 kg·m(-2); Tanner -4; 61.5 ± 8.9, 10 repetition maximum [RM]) and 15 adults (22.2 ± 2.7 years; 23.3 ± 2.0 kg·m(-2); Tanner -5; 84.3 ± 13.5, 10RM) without previous experience with resistance training participated in the study. After 10RM test-retest on 3 different occasions, participants were randomly assigned to a resistance training protocol with 30-, 60-, and 120-second rest interval between sets. The protocol consisted of 3 sets with 10RM. In all studied variables, with exception to total training volume and RPE, adolescents presented superior results as compared with adults (p < 0.001). On the other hand, both adults and adolescents exhibited a higher resistance to fatigue, total training volume, and number of repetitions with a longer rest interval (120 > 60 > 30 seconds) (p < 0.01). Thus, these results indicate that adolescents present a higher recovery capacity between sets in a resistance training session than adults and a longer rest interval results in a higher number of repetitions completed, total training volume, and resistance to fatigue. 相似文献
993.
Timoteo T. Watanabe Fabiana A. Nascimento Fernando L. Mantelatto Fernando J. Zara 《Journal of morphology》2020,281(12):1660-1678
We described the ultrastructure and histochemistry of the reproductive system of five Callinectes species, and evaluate the seasonal variation in weight of the reproductive system and hepatopancreas by comparing annual changes of somatic indices. The somatic indices changed little throughout the year. In Callinectes, spermatogenesis occurs inside the lobular testes and, within each lobule, the cells are at the same developmental stage. Spermatogenesis and spermiogenesis follow the same development pattern in all Callinectes studied. Mature spermatozoa are released into the seminiferous ducts through the collecting ducts. Cells of the vas deferens are secretory as evidenced by rough endoplasmic reticulum, Golgi complex, and secretory vesicles that produce the seminal fluid. The anterior vas deferens shows two portions: proximal and distal. In proximal portion (AVDp), spermatozoa are clustered and embedded in an electron-dense, basophilic glycoproteinaceous secretion Type I. In the distal portion (AVDd), the spermatophore wall is formed by incorporation of a less electron-dense glycoproteinaceous secretion Type II. The secretion Type I change to an acid polysaccharide-rich matrix that separates the spermatophores from each other. The median vas deferens (MVD) stores the spermatophores and produces the granular glycoproteinaceous seminal fluid. The posterior vas deferens (PVD) has few spermatophores. Its epithelium has many mitochondria and the PVD seminal fluid changes into a liquid and homogeneous glycoprotein. Many outpocketings in the PVD and MVD help to increase the fluid production. Overall, the reproductive pattern of Callinectes is similar to other species that produce sperm plugs. The secretions of AVD, MVD, and PVD are responsible for the polymerization that forms the solid, waxy plug in the seminal receptacle. The traits identified here are common to all Portunidae species studied so far. 相似文献
994.
da Silva Nayara Tayane Silva Lázara Aline Simões Reis Aryane Campos Machado Mariana de Matos Elyabe Monteiro Viccini Lyderson Facio Otoni Wagner Campos de Carvalho Ilio Fealho Rocha Diego Ismael da Silva Maurecilne Lemes 《Plant Cell, Tissue and Organ Culture》2020,142(3):613-624
Plant Cell, Tissue and Organ Culture (PCTOC) - Triploid plants represent an important resource for the breeding of fruit and ornamental plants. Here, we report a facile and robust system for... 相似文献
995.
André Luís Branco de Barros Valbert Nascimento Cardoso Luciene das Graças Mota Elaine Amaral Leite Mônica Cristina de Oliveira Ricardo José Alves 《Bioorganic & medicinal chemistry letters》2009,19(9):2497-2499
A d-glucose-MAG3 derivative was successfully synthesized and radiolabeled in high labeling yield. Biodistribution studies in Ehrlich tumor-bearing mice were performed. This compound showed high accumulation in tumor tissue with high tumor-to-muscle ratio and moderate tumor-to-blood ratio. Thus, d-glucose-MAG3 is a potential agent for tumor diagnosis. 相似文献
996.
Nascimento Ana Carolina Erustes Adolfo G. Reckziegel Patrícia Bincoletto Claudia Ureshino Rodrigo P. Pereira Gustavo J. S. Smaili Soraya S. 《Neurochemical research》2020,45(11):2749-2761
Neurochemical Research - Although the etiology of Parkinson's disease (PD) is multifactorial, it has been linked to abnormal accumulation of α-synuclein (α-syn) in dopaminergic... 相似文献
997.
Alexandre T. Amaral Nascimento Lucia A.J. Schmidlin Claudio B. Valladares‐Padua Eliana R. Matushima Luciano M. Verdade 《American journal of primatology》2011,73(11):1114-1126
The critically endangered black‐faced lion tamarin, Leontopithecus caissara, has a restricted geographical distribution consisting of small mainland and island populations, each with distinct habitats in coastal southeastern Brazil. Necessary conservation management actions require an assessment of whether differences in habitats are reflected in use of space by the species. We studied two tamarin groups on the mainland at São Paulo state between August 2005 and March 2007, and compared the results with data from Superagui Island. Three home range estimators were used: minimum convex polygon (MCP), Kernel, and the new technique presented dissolved monthly polygons (DMP). These resulted, respectively, in home ranges of 345, 297, and 282ha for the 12‐month duration of the study. Spatial overlap of mainland groups was extensive, whereas temporal overlap was not, a pattern that indicates resource partitioning is an important strategy to avoid intraspecific competition. L. caissara large home ranges seem to be dynamic, with constant incorporation of new areas and abandonment of others through time. The main difference between mainland and island groups is the amount and variety of sleeping sites. A better understanding of the home range sizes, day range lengths, and territorial behavior of this species will aid in developing better management strategies for its protection. Additionally, the presented DMP protocol is a useful improvement over the MCP method as it results in more realistic home range sizes for wildlife species. Am. J. Primatol. 73:1114–1126, 2011. © 2011 Wiley Periodicals, Inc. 相似文献
998.
Katharina Fitzian Anne Brückner Laura Brohée Reinhard Zech Claudia Antoni Stephan Kiontke Raphael Gasper Anna Livia Linard Matos Stephanie Beel Sabine Wilhelm Volker Gerke Christian Ungermann Mark Nellist Stefan Raunser Constantinos Demetriades Andrea Oeckinghaus Daniel Kümmel 《Molecular cell》2021,81(13):2705-2721.e8
999.
Fernanda Borowsky da Rosa Victor Costa de Souza Tatiana Amaral Pires de Almeida Valdinete Alves do Nascimento Felicien Gon?alves Vásquez Maria da Gra?a Souza Cunha Felipe Gomes Naveca 《Memórias do Instituto Oswaldo Cruz》2013,108(5):572-577
The aim of this study was to investigate sensitivity disorders in the
oral cavity related to the presence of Mycobacterium leprae in
the saliva of treatment-naïve patients with leprosy in the state of Amazonas,
Brazil. A cross-sectional study was conducted involving 45 subjects with
leprosy. The subjects were interviewed to evaluate the sensitivity of the oral
cavity. For the detection of M. leprae, saliva and slit-skin
smear samples were collected. The samples were analysed using a bacteriological
index (BI) protocol and the real-time quantitative polymerase chain reaction
(qPCR). The results indicated that 15 of the 45 (33.3%) subjects with leprosy
showed decreased oral sensitivity, which confirmed the importance of the oral
cavity sensitivity evaluation. There was not a direct relationship between the
presence of M. leprae in saliva and changes in oral
sensitivity. Positive saliva qPCR results from six (31.6%) of 19 paucibacillary
(PB) patients suggested the possibility of a new site for sample collection.
Positive results using these diagnostic techniques (BI, slit-skin smear and
saliva qPCR) increased to 55.5%, thus opening the possibility of combining these
different techniques to increase the rate of positive diagnoses, especially in
PB patients. 相似文献
1000.
Joana Rocha-Pereira Dirk Jochmans Yannick Debing Erik Verbeken Maria S. J. Nascimento Johan Neyts 《Journal of virology》2013,87(21):11798-11805
Human noroviruses are a major cause of food-borne illness, accountable for 50% of all-etiologies outbreaks of acute gastroenteritis (in both developing and developed countries). There is no vaccine or antiviral drug for the prophylaxis or treatment of norovirus-induced gastroenteritis. We recently reported the inhibitory effect of 2′-C-methylcytidine (2CMC), a hepatitis C virus polymerase inhibitor, on the in vitro replication of murine norovirus (MNV). Here we evaluated the inhibitory effect of 2CMC on in vitro human norovirus replication through a Norwalk virus replicon model and in a mouse model by using AG129 mice orally infected with MNV. Survival, weight, and fecal consistency were monitored, and viral loads in stool samples and organs were quantified. Intestines were examined histologically. 2CMC reduced Norwalk virus replicon replication in a dose-dependent manner and was able to clear cells of the replicon. Treatment of MNV-infected AG129 mice with 2CMC (i) prevented norovirus-induced diarrhea; (ii) markedly delayed the appearance of viral RNA and reduced viral RNA titers in the intestine, mesenteric lymph nodes, spleen, lungs, and stool; (iii) completely prevented virus-induced mortality; and (iv) resulted in protective immunity against a rechallenge. We demonstrate for the first time that a small-molecule inhibitor of norovirus replication protects from virus-induced disease and mortality in a relevant animal model. These findings pave the way for the development of potent and safe antivirals as prophylaxis and therapy of norovirus infection. 相似文献