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951.
Wendt Lucas Mallmann Soldateli Francis Júnior Both Vanderlei Thewes Fabio Rodrigo Ludwig Vagner Berghetti Magno Roberto Pasquetti dos Santos Ferrão Tassiane Wagner Roger Brackmann Auri 《Journal of Plant Growth Regulation》2023,42(2):701-718
Journal of Plant Growth Regulation - This study aimed to evaluate the interaction of ethylene management in the pre- and post-harvest stages using different storage techniques on the... 相似文献
952.
Ari S. O. Lemos Lara M. Campos Thalita F. Souza Priscila L. Paula João Victor G. Da Silva Elaine S. Coimbra Eugenio D. Hottz Paula R. B. Dib Jair A. K. Aguiar Richard M. Grazul Luciana M. Chedier Rodrigo L. Fabri 《化学与生物多样性》2023,20(1):e202200624
In recent years, natural products with biological activities have been increasingly researched. The elucidation of phytoconstituents is necessary for the development of drugs as a natural alternative for the treatment of various diseases. The work aimed to evaluate in vitro and in silico bioactivities of hexane (CCHE) and methanol (CCME) fractions of ethanolic extract from Centrosema coriaceum Benth (Fabaceae) leaves and elucidate their phytoconstituents. CCHE and CCME showed antifungal activity for Candida glabrata (MIC of 1000 μg/mL) with fungistatic effect and action in cell envelope by sorbitol and ergosterol assays. CCHE and CCME presented promising antioxidant activity against the DPPH radical with IC50 of 13.61±0.50 and 6.31±0.40 μg/mL, respectively, and relative antioxidant activity (RAA%) of 45.77±3.61/ 28.53±2.25 % for CCHE and 82.18±2.25/51.99±3.23 % for CCME when compared to rutin and quercetin, respectively. Moreover, these fractions demonstrated promising results for the inhibition of lipid peroxidation by β-carotene/linoleic acid assay. For anti-inflammatory and cytotoxicity activities, CCHE and CCME significantly inhibited the production of nitric oxide and TNF-α, without toxicity on murine intraperitoneal macrophages, respectively. Esters, alkanes, steroids, tocopherols, and terpenes were identified in CCHE by GC/MS. Flavonoids, phenolic acids, and disaccharides were detected in CCME by UFLC-QTOF-MS and FACE. Furthermore, rutin was purified from CCME. In silico predictions evidenced that compounds present in both fractions have high affinity to the fungal membrane besides antioxidant and anti-inflammatory activities. Based on these observations, CCHE and CCME have a noteworthy potential for the design of novel antifungal and anti-inflammatory agents that should be explored in future studies. 相似文献
953.
Rodrigo Infante Annalisa Rotondi Grazia Marino Francesca Fasolo 《In vitro cellular & developmental biology. Plant》1994,30(3):160-163
Summary Proliferating axillary shoots of kiwifruit (Actinidia deliciosa A. Chev., C. F. Liang and A. R. Ferguson), var.deliciosa, cv. ‘Hayward’ were grown under solar (SL), white (WL), and blue (BL) light regimens to determine the accumulation of fresh
and dry weight, proliferation rate, shoot growth (length), and the net leaf photosynthetic capacity at the CO2 concentration ranges of 200 to 350, 400 to 600, and 1200 to 1500 ppm. An histologic study determined the effects of light
source on leaf stomatal density and tissue morphology. Dry and fresh matter accumulation was greatest, but callus development
most limited under the SL regimen. Shoot proliferation was highest under WL and length under BL. Net photosynthetic capacity
was highest for leaves grown under SL and lowest for those under BL; the leaves exposed to the latter regimen were also thinner
and exhibited a less compact arrangement of palisade cells than those under WL and SL. Leaf stomata density was highest under
the BL source. 相似文献
954.
Esteban BoteroDelgadillo Vernica Quirici Silvina Ippi Rodrigo A. Vsquez Bart Kempenaers 《Ecology and evolution》2022,12(3)
Investigating whether mating patterns are biased in relation to kinship in isolated populations can provide a better understanding of the occurrence of inbreeding avoidance mechanisms in wild populations. Here, we report on the genetic relatedness (r) among breeding pairs in a relict population of Thorn‐tailed Rayadito (Aphrastura spinicauda) in north‐central Chile that has experienced a long‐term history of isolation. We used simulations based on 8 years of data to assess whether mating is random with respect to relatedness. We found that mean and median population values of pair relatedness tended to be lower than randomly generated values, suggesting that mating is not random with respect to kinship. We hypothesize that female‐biased dispersal is the main mechanism reducing the likelihood of mating among kin, and that the proportion of related pairs (i.e., r > 0.125) in the study population (25%) would presumably be higher in the absence of sex‐biased dispersal. The occurrence of other mechanisms such as extra‐pair copulations, delayed breeding, and active inbreeding avoidance through kin discrimination cannot be dismissed and require further study. 相似文献
955.
956.
Alan de Albuquerque Melo Victor Jos Bastos-Silva Felipe Arruda Moura Rodrigo Rico Bini Adriano Eduardo Lima-Silva Gustavo Gomes de Araujo 《Biology of sport / Institute of Sport》2021,38(4):517
We investigated the effects of caffeine mouth rinse on endurance performance, muscle recruitment (i.e., electromyographic activity of the vastus lateralis and rectus femoris), rating of perceived effort and heart rate. Twelve physically-active healthy men cycled at 80% of their respiratory compensation point until task failure. The participants rinsed their mouths for 10 seconds with placebo (PLA, 25 mL of a solution composed of non-caloric mint essence) or caffeine (CAF, 25 mL of 1.2% of anhydrous caffeine concentration with non-caloric mint essence) every 15 minutes of exercise. Time until exhaustion increased 17% (effect size = 0.70) in CAF compared to PLA (p = 0.04). The wavebands of low-frequency electromyographic activity (EMG) of the vastus lateralis and rectus femoris was lower in CAF group than PLA at 50% of the time until exhaustion (p = 0.04). The global EMG signal was lower in CAF group than PLA at 100% of the time until exhaustion (p = 0.001). The rating of perceived effort pooled was higher in CAF mouth rinse (p = 0.001) than PLA group. No effect was found on the heart rate between the groups (p > 0.05). Caffeine mouth rinse increases endurance performance, rating of perceived effort and decreases muscle activity during a moderate-intensity exercise. 相似文献
957.
Walter Pangborn Mary Erman Naiyin Li Brian M. Burkhart Vladimir Z. Pletnev William L. Duax Rodrigo Gutierrez Alessandra Peirano Jaime Eyzaguirre Daniel J. Thiel Debashis Ghosh 《Proteins》1996,24(4):523-524
Acetyl xylan esterase from Penicillium purpurogenum, a single-chain 23 kDa member of a newly characterized family of esterases that cleaves side chain ester linkages in xylan, has been crystallized. The crystals diffract to better than 1 Å resolution at the Cornell High Energy Synchrotron Source (CHESS) and are highly stable in the synchrotron radiation. The space group is P212121 and cell dimensions are a = 34.9 Å, b = 61.0 Å, c = 72.5 Å. 相似文献
958.
Susana Castro-Blanco Juan Manuel Encinas Julia Serrano David Alonso María Benita Gómez Jaime Sánchez Francisco Ríos-Tejada Paula Fernández-Vizarra Ana Patricia Fernández Ricardo Martínez-Murillo José Rodrigo 《Nitric oxide》2003,8(3):182-201
Changes in the nitric oxide (NO) system of the rat cerebral cortex were investigated by immunohistochemistry, immunoblotting, and NO synthase (NOS) activity assays in adult rats submitted for 30 min to hypoxia, in a hypobaric chamber at a simulated altitude of 38,000 ft (11000 m) (154.9 mm Hg). The cerebral cortex was studied after different survival times, 0 and 24 h, 5, 8, 15, and 30 days of reoxygenation. This situation led to morphological alterations in the large type I interneurons, as well as immunoreactive changes in the appearance and number of the small neurons (type II), both containing neuronal NOS (nNOS). Some of these small neurons showed immunoreactive cytoplasm and short processes; others, the more numerous during all reoxygenation periods, contained the immunoreactive product mainly related to a perinuclear ring. Ultrastructurally, these small neurons exhibited changes in nuclear structures as in the shape of the nuclear membrane, in the distribution of heterochromatin, and in the nucleolar morphology. The reaction product for nitrotyrosine, as a marker of protein nitration, showed modifications in distribution of the immunoreactive product. No expression was found for inducible NOS (iNOS). All these modifications were accompanied by increased nNOS and nitrotyrosine production as demonstrated by Western blotting and calcium-dependent activity, returning to control conditions after 30 days of reoxygenation, suggesting a reversible NO mechanism of action. 相似文献
959.
Choueri Rodrigo B.; Melao Maria Da Graca G.; Lombardi Ana T.; Vieira Armando A. H. 《Journal of plankton research》2007,29(4):339-345
The objective of the present investigation was to verify ifAnabaena spiroides exopolysaccharides sustains growth and reproductionof Ceriodaphnia cornuta. The animals were raised in controlledlaboratory conditions and fed exclusively on A. spiroides exopolysaccharides,which were obtained from filtered stationary growth phase A.spiroides cultures. A molecular weight cut-off of 1214kDa was used to separate the exopolysaccharides from low molecularweight materials. The lyophilized exopolysaccharides were dissolvedin filtered and autoclaved reservoir water at a concentrationof 15 mg L1 (0.22 ± 0.01 mg C animal1day1).These results were compared with animals fed on seston at naturalconcentration obtained by filtering (68 µm) Barra BonicaReservoir water (0.23 ± 0.01 mg C animal1day1).Several life history parameters (duration of embryonic development,generation time, reproductive performance, age-specific length,primipara age and length) were obtained during 15-day experiments.Growth rate (GR) and weight-specific secondary production werealso quantified. Exopolysaccharide-fed organisms had bettergrowth and reproductive performance (0.091 ± 0.004 GR;51 ± 4.59 eggs produced per female) than seston-fed individuals(0.078 ± 0.010 GR; 30.90 ± 7.25 eggs producedper female). These results show that such macromolecules area potential food source, fulfilling nutritional requirementsto sustain growth and reproduction of C. cornuta and supportstrophic relationships in aquatic ecosystems. 相似文献
960.
The use of Assisted Reproductive Technologies (ARTs) in modern cattle breeding is an important tool for improving the production of dairy and beef cattle. A frequently employed ART in the cattle industry is in vitro production of embryos. However, bovine in vitro produced embryos differ greatly from their in vivo produced counterparts in many facets, including developmental competence. The lower developmental capacity of these embryos could be due to the stress to which the gametes and/or embryos are exposed during in vitro embryo production, specifically ovarian hormonal stimulation, follicular aspiration, oocyte in vitro maturation in hormone supplemented medium, sperm handling, gamete cryopreservation, and culture of embryos. The negative effects of some ARTs on embryo development could, at least partially, be explained by disruption of the physiological epigenetic profile of the gametes and/or embryos. Here, we review the current literature with regard to the putative link between ARTs used in bovine reproduction and epigenetic disorders and changes in the expression profile of embryonic genes. Information on the relationship between reproductive biotechnologies and epigenetic disorders and aberrant gene expression in bovine embryos is limited and novel approaches are needed to explore ways in which ARTs can be improved to avoid epigenetic disorders. 相似文献