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971.
972.
Rosa Karla Nogueira Pestanana Edson Perito Amorim Cláudia Fortes Ferreira Vanusia Batista de Oliveira Amorim Larissa Santos Oliveira Carlos Alberto da Silva Ledo Sebastião de Oliveira e Silva 《Euphytica》2011,178(2):151-158
Bananas are tropical fruits grown worldwide playing a key role in market trade and especially used as main food source for
low income populations. In Brazil, bananas are mainly consumed in natura, occupying the second largest internal market. Nevertheless, this crop presents low availability of productive commercial
varieties with good agronomic characteristics. A strategy undertaken to solve this problem is the development of new cultivars
through conventional genetic breeding methods. However, this strategy presents some obstacles such as female sterility and
low number of seeds. In order to overcome these shortcomings, use of mutation induction aiming the selection of mutants with
desirable agronomic characteristics seems to have great potential for developing new cultivars. The objective of the present
work was to evaluate the genetic variability in putative banana ‘Pacovan’ (AAB genome, subgroup Prata Type) mutants submitted
to gamma ray irradiation, using a set of agronomical and molecular data (ISSR markers). The distance between the putative
‘Pacovan’ mutants varied from 0.26 to 0.64 with cophenetic correlation coefficient of 0.7669. Four mutants were selected based
on best agronomical characteristics and height. This data also shows that there is variability that can be explored after
the irradiation of ‘Pacovan’ banana mutants, which can be used in the genetic breeding program of banana aiming to develop
short new varieties that also present good agronomic characteristics. This is the first attempt to use combined data in order
to evaluate the genetic variability in putative banana mutants. 相似文献
973.
Kelsey M Schubach Reinaldo F Cooke Courtney L Daigle Alice P Brando Bruna Rett Vitor S M Ferreira Giovanna N Scatolin Eduardo A Colombo Genevieve M DSouza Ky G Pohler Bruno I Cappellozza 《Journal of animal science》2020,98(9)
This experiment evaluated the impacts of administering a bovine appeasing substance (BAS) to beef calves at weaning on their performance, physiological responses, and behavior during a 42-d preconditioning program. Eighty calves (40 heifers and 40 steers; 90% British × 10% Nellore) were weaned at 233 ± 2 d of age (day 0); ranked by sex, weaning age, and body weight (BW); and assigned to receive BAS (IRSEA Group, Quartier Salignan, France; n = 40) or placebo (diethylene glycol monoethyl ether; CON; n = 40). Treatments (5 mL) were topically applied to the nuchal skin area of each animal following dam separation. Within treatment, calves were allocated to one of eight drylot pens (four pens per treatment; pen being the experimental unit) and received a free-choice total mixed ration (TMR) from day 0 to 42, intake of which was assessed daily. Live behavior observations were conducted on days 1, 2, 4, 8, 16, and 32. Temperament was assessed and blood samples were collected via jugular venipuncture on days −21, 0, 3, 7, 14, 28, and 42. Hair samples were collected from the tail switch on days 0, 14, 28, and 42. Calves were vaccinated against bovine respiratory disease viruses on days −21 and 0. Average daily gain from day 0 to 42 did not differ between treatments (P = 0.57) but was greater (P = 0.05) in BAS vs. CON calves from day 0 to 28. Intake of TMR was greater (P = 0.05) during the first week for BAS vs. CON calves (treatment × week; P = 0.08). The mean proportion of calves feeding simultaneously and performance of social and play behaviors were greater (P ≤ 0.05) for BAS vs. CON calves. Escape attempts were greater (P < 0.01) for BAS vs. CON calves on day 1 (treatment × day; P = 0.03). Exit velocity was greater (P = 0.04) for CON vs. BAS calves on day 14 and tended (P = 0.10) to be greater for CON vs. BAS calves on day 7 (treatment × day; P = 0.03). Mean plasma concentrations of haptoglobin were greater (P = 0.02) in CON vs. BAS calves. Hair cortisol concentrations were greater (P = 0.05) in CON vs. BAS calves on day 14 (treatment × day; P = 0.03). Mean serum concentrations of antibodies against bovine viral diarrhea virus were greater (P = 0.02) in BAS vs. CON calves. Collectively, BAS administration to beef calves at weaning alleviated stress-induced physiological reactions, improved temperament evaluated via chute exit velocity, enhanced humoral immunity acquired from vaccination, and appeared to have accelerated adaptation to novel management scheme and environment. 相似文献
974.
de Araújo Hosaneide Gomes da Silva Juliana Trajano Álvares Felipe Boniedj Ventura Ferreira Larissa Claudino Azevedo Sérgio Santos Vilela Vinícius Longo Ribeiro 《Tropical animal health and production》2020,52(1):379-385
Tropical Animal Health and Production - In northeastern Brazil, with has a predominantly dry climate, farmers seek alternative sources of income and livelihood by the rearing pigs. The... 相似文献
975.
Malikouski Renan Garcia Alves Rodrigo Silva Peixoto Marco Antônio Ferreira Filipe Manoel do Nascimento Emanuel Ferrari de Morais Andréia Lopes Zucoloto Moises das Graças Dias Kaio Olimpio Bhering Leonardo Lopes 《Euphytica》2022,218(11):1-21
Euphytica - Drought tolerance in maize is a complex and polygenic trait, especially in the seedling stage. In plant breeding, complex genetic traits can be improved by genomic selection (GS), which... 相似文献
976.
Rafaela Guimarães Lillian Barros Ricardo C. Calhelha Ana Maria Carvalho Maria João R. P. Queiroz Isabel C. F. R. Ferreira 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(1):37-42
Arbutus unedo, Prunus spinosa, Rosa micrantha and Rosa canina are good sources of phenolic compounds, including anthocyanins. These compounds have potent antioxidant properties, which have been related to anticancer activity. Herein, the in vitro antioxidant and antitumor properties of enriched phenolic extracts (non-anthocyanin phenolic compounds enriched extract- PE and anthocyanins enriched extract- AE) of the mentioned wild fruits were evaluated and compared. PE gave higher bioactive properties than the corresponding AE. It was observed a high capacity of A. unedo phenolic extract to inhibit lipid peroxidation in animal brain homogenates (EC50?=?7.21 μg/mL), as also a high antitumor potential against NCI-H460 human cell line (non-small lung cancer; GI50?=?37.68 μg/mL), which could be related to the presence of galloyl derivatives (exclusively found in this species). The bioactivity of the studied wild fruits proved to be more related to the phenolic compounds profile than to the amounts present in each extract, and could be considered in the design of new formulations of dietary supplements or functional foods. 相似文献
977.
Ferreira Diego Henrique Moreira Rafaele Regina Silva Junior Geraldo José Behlau Franklin 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):891-906
European Journal of Plant Pathology - Citrus canker and citrus black spot are two of the most important diseases in the São Paulo (SP) citrus belt, Brazil. Canker control was based on an... 相似文献
978.
Marisa Rangel Joyce C. G. Martins Angélica Nunes Garcia Geanne A. A. Conserva Adriana Costa-Neves Célia Leite Sant’Anna Luciana Retz de Carvalho 《Marine drugs》2014,12(1):508-524
Cyanobacteria are common members of the freshwater microbiota in lakes and drinking water reservoirs, and are responsible for several cases of human intoxications in Brazil. Pseudanabaena galeata and Geitlerinema splendidum are examples of the toxic species that are very frequently found in reservoirs in Sao Paulo, which is the most densely populated area in Brazil. In the search for toxic strains collected from water reservoirs and maintained in the Cyanobacterial Culture Collection (CCIBt) of the Institute of Botany of Brazil, the acetic acid extracts (AE) of P. galeata CCIBt 3082 and G. splendidum CCIBt 3223 were analyzed by planar chromatography, which indicated the absence of cyanotoxins. Animal tests were then carried out, and both extracts were found to induce toxic effects in mice when administered intraperitoneally. The present study aimed to investigate whether the oral ingestion of the above mentioned cyanobacteria extracts would also induce toxic effects in mice. Necropsy and histopathological studies were conducted using tissue samples from the animals, which were euthanized one week after the administration of the extracts. The AE of P. galeata did not cause death but did induce transient symptoms, including eyebrow ptosis, straub tail, and pain. The euthanized animals presented hemorrhage in the liver, whereas the histological analysis showed disorganization of the hepatic parenchyma, necrosis, hyperemia, and proximity of the centrilobular vein in the liver. In addition, alterations in the convoluted tubules of the kidneys were observed, and the lungs were unaffected. The AE of G. splendidum caused only one death, and induced transient symptoms, such as dyspnea, paralysis, and pain, in the other mice. The necropsy of the euthanized mice showed hemorrhage in the lungs and liver. The lungs presented hemorrhagic focuses, alveolar collapse, and granulomatous foci. The liver presented hemorrhagic and enlarged sinusoids, hyperemia, proximity of the centrilobular vein, and disorganization of the hepatic parenchyma. Some areas also exhibited an inflammatory infiltrate and calcified tissue inside blood vessels. Necrosis and rupture of the convoluted tubule cells were observed in the kidneys. Further analysis of the both extracts indicated the lack of hemolytic activity, and the presence of two unknown anti-AChE substances in the AE of G. splendidum. Thus, P. galeata and G. splendidum are producers of novel toxins that affect mammals when administered orally. 相似文献
979.
Alessandra Mirtes Marques Neves Gon?alves Aline Brito de Lima Maria Cristina da Silva Barbosa Luiz Fernando de Camargos Júlia Teixeira de Oliveira Camila de Souza Barbosa José Augusto Ferreira Perez Villar André Carvalho Costa Isabella Viana Gomes da Silva Luciana Maria Silva Fernando de Pilla Varotti Fabio Vieira dos Santos Gustavo Henrique Ribeiro Viana 《Marine drugs》2014,12(8):4361-4378
Cancer continues to be one of the most important health problems worldwide, and the identification of novel drugs and treatments to address this disease is urgent. During recent years, marine organisms have proven to be a promising source of new compounds with action against tumoral cell lines. Here, we describe the synthesis and anticancer activity of eight new 3-alkylpyridine alkaloid (3-APA) analogs in four steps and with good yields. The key step for the synthesis of these compounds is a Williamson etherification under phase-transfer conditions. We investigated the influence of the length of the alkyl chain attached to position 3 of the pyridine ring on the cytotoxicity of these compounds. Biological assays demonstrated that compounds with an alkyl chain of ten carbon atoms (4c and 5c) were the most active against two tumoral cell lines: RKO-AS-45-1 and HeLa. Micronucleus and TUNEL assays showed that both compounds are mutagenic and induce apoptosis. In addition, Compound 5c altered the cellular actin cytoskeleton in RKO-AS-45-1 cells. The results suggest that Compounds 4c and 5c may be novel prototype anticancer agents. 相似文献
980.
Miyahira Roberta Fontanive de Lima Pena Fabíola Fabiano Giovanna Alexandre de Oliveira Lopes Jean Ponte Luis Gustavo Saboia da Cunha Diogo Thimoteo Bezerra Rosangela Maria Neves Antunes Adriane Elisabete Costa 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(2):233-240
Plant Foods for Human Nutrition - The consumption of sprouts has increased as the germination process causes changes in the chemical composition of the seeds, improving their nutritional value. The... 相似文献