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101.
Faustino Verônica Aparecida de Almeida Barros Rafael da Silva Júnior Neilier Rodrigues Barbosa Samuel Lessa Vital Camilo Elber da Silva Felipe Lopes Cabrera Yaremis Beatriz Meriño Campos Wellington Garcia de Oliveira Ramos Humberto Josué de Almeida Oliveira Maria Goreti 《Phytoparasitica》2021,49(4):491-500
Phytoparasitica - Soybean plants are exposed to multiple stresses during development. Co-occurring stresses can activate common defense pathways on plants, increasing end products concentrations,... 相似文献
102.
VRP Barros AYP Cavalcante TJS Macedo RS Barberino TLB Lins BB Gouveia VG Menezes MAA Queiroz VR Araújo RC Palheta Jr MCP Leite MHT Matos 《Reproduction in domestic animals》2013,48(6):1025-1033
The expression of melatonin type 1 (MT1) and FSH (FSHR) receptors in caprine ovaries and the effects of these hormones on the in vitro development of isolated pre‐antral follicles were evaluated. Follicles (≤200 μm) were cultured for 12 days in α‐MEM (control) or melatonin (100 or 1000 pg/ml) or sequential melatonin medium (100 pg/ml: from day 0 to day 6; 1000 pg/ml: from day 6 to day 12; experiment 1) and in control or sequential FSH (100 ng/ml from day 0 to day 6; 500 ng/ml from day 6 to day 12) or sequential melatonin or this latter plus sequential FSH (experiment 2). MT1 and FSHR expressions were observed in granulosa cells from secondary and antral follicles. The oocytes from primordial and primary follicles also express FSHR. Sequential melatonin increased the percentage of normal follicles and oocyte recovery compared with the control or melatonin (1000 pg/ml) at day 12. In experiment 2, all the treatments increased the normal follicles and growth compared with the control. In conclusion, this study demonstrated the presence of MT1 and FSHR in caprine ovaries. The addition of increased concentrations of melatonin (sequential medium) or FSH can be used to promote the in vitro development of caprine pre‐antral follicles. 相似文献
103.
F. M. Da Matta M. Maestri R. S. Barros A. J. Regazzi 《The Journal of Horticultural Science and Biotechnology》2013,88(5):741-746
Coffee plants of five Arabica and one Canephora genotypes were raised in containers with 0.02 nr1 of soil, under a clear plastic shelter. When they were 18 months old, irrigation was withheld until the first signs of wilting appeared. This occurred four to five days after withholding irrigation, when the pre-dawn water potential of young fully expanded leaves of the plagiotropic branches was about -2.4 MPa. Control plants remained under daily irrigation. The pressure-volume technique was used to estimate volume averaged water relations properties of sample leaves. The turgor loss point was approximately -1.6 MPa for control plants and -2.0 MPa for stressed plants, an osmotic adjustment of approximately 22%. The Canephora genotype showed a slightly higher adjustment. The relative water content at the turgor loss point remained at approximately 93%, irrespective of genotype or treatment. The maximum bulk modulus of elasticity did not change significantly with water deficit, remaining at about 24 MPa, except for a slight increase in the Canephora genotype. The specific leaf area of the Arabica genotypes decreased about 20%, as compared with a 10% decrease for the Canephora genotype. 相似文献
104.
Margarida Costa Jo?o Costa-Rodrigues Maria Helena Fernandes Piedade Barros Vitor Vasconcelos Rosário Martins 《Marine drugs》2012,10(10):2181-2207
Marine cyanobacteria have been considered a rich source of secondary metabolites with potential biotechnological applications, namely in the pharmacological field. Chemically diverse compounds were found to induce cytoxicity, anti-inflammatory and antibacterial activities. The potential of marine cyanobacteria as anticancer agents has however been the most explored and, besides cytotoxicity in tumor cell lines, several compounds have emerged as templates for the development of new anticancer drugs. The mechanisms implicated in the cytotoxicity of marine cyanobacteria compounds in tumor cell lines are still largely overlooked but several studies point to an implication in apoptosis. This association has been related to several apoptotic indicators such as cell cycle arrest, mitochondrial dysfunctions and oxidative damage, alterations in caspase cascade, alterations in specific proteins levels and alterations in the membrane sodium dynamics. In the present paper a compilation of the described marine cyanobacterial compounds with potential anticancer properties is presented and a review on the implication of apoptosis as the mechanism of cell death is discussed. 相似文献
105.
Caroline Pelegrina Teixeira Margarida Maria Barros Luiz Edivaldo Pezzato Ademir Calvo Fernandes Jr João Fernando Albers Koch Carlos Roberto Padovani 《Aquaculture Research》2012,43(8):1081-1088
In order to assess the effect of dietary pyridoxine supplementation on the growth performance of Nile tilapia and the haematological response under heat stress, 192 fingerlings (8.41 ± 0.22 g) were randomly distributed into eight tanks and fed practical diets supplemented with increasing levels of pyridoxine (0.0; 5.0; 10.0 and 20.0 mg of pyridoxal HCl kg?1 diet) for 91 days. The fish were then weighed and the diet was quantified to determine the growth performance [weight gain (WG), feed intake, feed conversion ratio, protein efficiency rate, protein retention (PR) and survival percentage]. Haematological analyses (red blood cell count, haematocrit, haemoglobin, total leucocyte and differentiation, mean corpuscular volume, mean corpuscular haemoglobin concentration, albumin, globulin and albumin/globulin ratio) were carried out and then 32 fish were transferred and subjected to heat stress (32 °C) for 3 days, after which the haematological parameters were analysed. The fish fed the unsupplemented diet showed the lowest WG and PR. For the normal growth and health of the Nile tilapia, the Pyridoxine requirement in a practical diet is 10.0 mg of pyridoxine HCl kg?1. 相似文献
106.
Cátia dos Santos Branco Émilin Dreher de Lima Elisa Pavão Lúcia Rosane Bertholdo-Vargas Neiva Monteiro de Barros 《国际虫害防治杂志》2014,60(2):114-120
Plant-derived products have been considered as an important alternative to common pesticides. Araucaria angustifolia extract (AAE) contains high levels of polyphenols, which are correlated with mortality in defoliating insects. Therefore, this study aimed to evaluate the effects of AAE treatments on A. gemmatalis larvae. Results showed that AAE was able to induce lipid, protein, and DNA damage in the larvae via oxidative stress. AAE treatment did not induce larvae mortality; however, there was an increase in the number of malformed pupae, along with a decrease in the emergence of the insects. These biological effects may be correlated with the polyphenol content of the AAE. 相似文献
107.
Phacoemulsification has been successfully employed in humans and animals for lens extraction. This ultrasonic extracapsular surgical technique induces hydroxyl radical formation in the anterior chamber, which accumulates despite irrigation and aspiration. In this paper we determined the total antioxidant status of aqueous humor after phacoemulsification by measuring aqueous humor ascorbic acid levels. Mixed-breed dogs (n = 11; weighing about 10 kg) with normal eyes as determined by slit-lamp biomicroscopy, applanation tonometry, and indirect ophthalmoscopy had phacoemulsification performed in one eye with the other eye used as a control. Samples of aqueous humor were obtained by anterior chamber paracentesis before surgery and at days 1, 2, 3, 7, and 15 after surgery. Total aqueous humor antioxidant status was inferred from the capacity of aqueous humor to inhibit free radical generation by 2,2-azobis (2-amidopropane) chlorine. Ascorbic acid concentrations were measured by high-pressure liquid chromatography with UV detection. Protein content was determined with the biuret reagent. Statistical analysis was performed by anova followed by the paired t-test. Total antioxidant capacity was reduced from 48 to 27 min during the first 24 h with a gradual increase thereafter, remaining statistically lower than the control eye until 7 days postoperatively. Reduced levels of ascorbic acid followed this reduction in antioxidant capacity (from 211 to 99 microm after 24 h), remaining lower than the control eye until 15 days postoperatively. Protein concentration in aqueous humor increased from 0.62 mg/mL to 30.8 mg/mL 24 h after surgery, remaining statistically lower than the control eye until 15 days postoperatively. Paracentesis alone did not significantly alter the parameters measured. These results indicate that after phacoemulsification, the aqueous humor ascorbic acid levels and antioxidant defenses in aqueous humor are reduced, indirectly corroborating free radical production in the anterior chamber as a result of phacoemulsification. The inflammatory process consequent to the surgical procedure demonstrated by increased protein content in aqueous humor can also contribute to free radical production and ascorbic acid consumption. 相似文献
108.
Falkoski DL Guimarães VM Callegari CM Reis AP de Barros EG de Rezende ST 《Journal of agricultural and food chemistry》2006,54(26):10184-10190
Galactooligosaccharides (GO) are responsible for intestinal disturbances following ingestion of legume-derived products. Enzymatic reduction of GO level in these products is highly desirable to improve their acceptance. For this purpose, plant and microbial semipurified alpha-galactosidases were used for GO hydrolysis in soybean flour and soy molasses. alpha-Galactosidases from soybean germinating seeds, Aspergillus terreus, and Penicillium griseoroseum presented maximal activities at pH 4.0-5.0 and 45-65 degrees C. The KM,app values determined for raffinose by the soybean, A. terreus, and P. griseoroseum alpha-galactosidases were 3.44, 19.39, and 20.67 mM, respectively. The enzymes were completely inhibited by Ag+ and Hg2+, whereas only soybean enzyme was inhibited by galactose. A. terreus alpha-galactosidase was more thermostable than the enzymes from the other two sources. This enzyme maintained about 100% of its original activity after 3 h at 60 C. The microbial alpha-galactosidases were more efficient for reducing GO in soybean flour and soy molasses than soybean enzyme. 相似文献
109.
da Silva Fialho L Guimarães VM de Barros EG Moreira MA Dos Santos Dias LA de Almeida Oliveira MG José IC de Rezende ST 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):87-89
Common beans have a high nutritional value, but contain galactooligosaccharides (GO), which cause flatulence and intestinal discomfort in humans. The biochemical composition of ten bean cultivars was determined to select those of high protein and low GO contents. The cultivars varied in carbohydrate (47.02-60.17%), GO (3.12-5.71%), protein (22.17-33.50%), lipid (1.13-1.81%), moisture (11.42-12.93%) and ash contents (4.08-5.61%). 'Mexico 222' presented the highest alpha-galactosidase activity. Protein and GO contents were positively correlated. 'Perry Marrow' combined high protein and low GO concentrations, indicating it can be used in improvement programs aiming at high-quality cultivars for human consumption. 相似文献
110.
Google Earth® provides free access to satellite images and has been used in several areas that require cartographic information. The present study assessed the inconsistencies between geo-referencing of livestock premises by GPS and the acquisition of geographic coordinates by remote sensing (RS) images provided by Google Earth® in the Brazilian states of Bahia, Distrito Federal, Minas Gerais and Parana. The overall mean and standard deviation of the distances in the study were 30.98 ± 19.89 m. The mean distance differences between the two techniques were, for these states, 37.20 ± 19.75 m, 28.38 ± 17.38 m, 31.61 ± 15.72 m, 28.43 ± 24.30 m, respectively. Despite the fact that there is variation between the geo-referencing points using GPS and RS, geographical localization of health inspections should be useful as long as the errors between the results of the two methodologies are considered. 相似文献