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991.
José P. F. Bentivenha Vinícius F. Canassa Edson L. L. Baldin Milena G. Borguini Giuseppina P. P. Lima André L. Lourenção 《Arthropod-Plant Interactions》2018,12(2):311-320
The stink bug complex includes some of the most important soybean pests worldwide. Among these insects, Piezodorus guildinii (Westwood) (Hemiptera: Pentatomidae) is known for the severe damage it can cause and for its resistance to chemical management. Host plant resistance is considered as an important tool in the management of these pests. In particular, plant flavonoids, such as genistein and rutin, have been identified as compounds that might negatively affect the development of some pests; however, the effects of these compounds on some stink bug species are still unclear. We tested the resistance of soybean genotypes by evaluating the growth and survival of P. guildinii under laboratory conditions. In addition, the amounts of genistein and rutin were quantified in both infested and non-infested genotypes. The PI 274453, PI 274454, PI 227687, PI 229358, ‘IAC 100′, and ‘IAC 19′ genotypes showed antibiosis to P. guildinii. The genistein and rutin flavonoids appear to play a role in the resistance of these genotypes against P. guildinii; specifically, PI 274453, PI 274454, and ‘IAC 100′ showed induced resistance against the insect. Other defence mechanisms or flavonoids might be involved in resistance in the L1-1-01 and PI 171451 genotypes. These results help us better understand the role of flavonoids in plant defence mechanisms and might prove useful in breeding programmes aimed at developing resistant soybean plants. 相似文献
992.
Dajana Blagojević Olivera Babić Milena Rašeta Filip Šibul Ljiljana Janjušević Jelica Simeunović 《Journal of applied phycology》2018,30(4):2337-2346
In the present study, ethanolic extracts of ten cyanobacterial strains cultivated under different nitrogen conditions were assessed for the phenolic content and antioxidant activity. The amount of detected phenolic compounds ranged from 14.86 to 701.69 μg g?1 dry weight (dw) and HPLC-MS/MS analysis revealed gallic acid, chlorogenic acid, quinic acid, catechin, epicatechin, kaempferol, rutin and apiin. Only catechin, among the detected phenolics, was present in all the tested strains, while quinic acid was the most dominant compound in all the tested Nostoc strains. The results also indicated the possibility of increasing the phenolic content in cyanobacterial biomass by manipulating nitrogen conditions, such as in the case of quinic acid in Nostoc 2S7B from 70.83 to 594.43 μg g?1 dw. The highest radical scavenging activity in DPPH assay expressed Nostoc LC1B with IC50 value of 0.04?±?0.01 mg mL?1, while Nostoc 2S3B with IC50 =?9.47?±?3.61 mg mL?1 was the least potent. Furthermore, the reducing power determined by FRAP assay ranged from 8.36?±?0.08 to 21.01?±?1.66 mg AAE g?1, and it was significantly different among the tested genera. The Arthrospira strains exhibited the highest activity, which in the case of Arthrospira S1 was approximately twofold higher in comparison to those in nitrogen-fixing strains. In addition to this, statistical analysis has indicated that detected phenolics were not major contributor to antioxidant capacities of tested cyanobacteria. However, this study highlights cyanobacteria of the genera Nostoc, Anabaena, and Arthrospira as producers of antioxidants and phenolics with pharmacological and health-beneficial effects, i.e., quinic acid and catechin in particular. 相似文献
993.
Pavel Hulva Barbora Černá Bolfíková Vendula Woznicová Milena Jindřichová Markéta Benešová Robert W. Mysłajek Sabina Nowak Maciej Szewczyk Natalia Niedźwiecka Michał Figura Andrea Hájková Atilla D. Sándor Vladimír Zyka Dušan Romportl Miroslav Kutal Slavomír Finďo Vladimír Antal 《Diversity & distributions》2018,24(2):i-i
994.
Eduardo Flavio Oliveira Ribeiro Vitorino Modesto dos Santos Guilherme Teixeira Guimarães Paixão Leonardo Rodrigues Cruz Milena Zamian Danilow Vinicius Ferreira Campos 《Mycopathologia》2013,175(3-4):295-300
We report a 38-year-old woman presenting with febrile neutropenia, acute myeloid leukemia (AML) and invasive mucormycosis. Bone marrow aspirate was characteristic of AML minimally differentiated (WHO classification 2008). Flow cytometric immunophenotyping analysis showed blasts positive for CD7, CD33, CD34, CD71, CD117, HLA-DR, MPO, and TdT, with normal karyotype (46, XX), and the absence of the FLT3-ITD and NPM1 mutations. The patient’s management included chemotherapy with cytarabine and idarubicin, and treatment with liposomal amphotericin B, deferasirox, hyperbaric oxygen therapy, and antibiotics. Nowadays, she is in complete hematological remission, and CT images of control are normal. Invasive mucormycosis is an uncommon and severe condition, which involves diagnosis and treatment challenges. Clinical features and predisposing factors should be highlighted in order to enhance the suspicion index, contributing to early diagnosis and disease control. Our aim is to report classical features of this uncommon condition and to emphasize usual management challenges. 相似文献
995.
Dinesh Srinivasan Milena Mechkarska Yasser H.A. Abdel-Wahab Peter R. Flatt J. Michael Conlon 《Biochimie》2013
Peptidomic analysis of norepinephrine-stimulated skin secretions of the tetraploid clawed frog Xenopus laevis (Pipidae) led to the identification of 10 peptides with the ability to stimulate the release of insulin from the rat BRIN-BD11 clonal β cell line. These peptides were purified to near homogeneity and structural characterization showed that they belong to the magainin (2 peptides), peptide glycine-leucine-amide (PGLa) (1 peptide), xenopsin precursor fragment (1 peptide), and caerulein precursor fragment (CPF) (6 peptides) families. CPF-1, CPF-3, CPF-5 and CPF-6 were the most potent producing a significant (P < 0.05) increase in the rate of insulin release at concentration of 0.03 nM. CPF-7 (GFGSFLGKALKAALKIGANALGGAPQQ) produced the maximum stimulation of insulin release (571 ± 30% of basal rate at 3 μM). In addition, CPF-SE1 (GFLGPLLKLGLKGVAKVIPHLIPSRQQ), previously isolated from skin secretions of the tetraploid frog Silurana epitropicalis, produced a significant (P < 0.05) increase in the rate of insulin release at 0.03 nM with a 514 ± 13% increase over basal rate at 3 μM. No CPF peptide stimulated release of the cytosolic enzyme, lactate dehydrogenase from BRIN-BD11 cells at concentrations up to 3 μM indicating that the integrity of the plasma membrane had been preserved. The mechanism of action of the CPF peptides involves, at least in part, membrane depolarization and an increase in intracellular Ca2+ concentration. The CPF peptides show potential for development into agents for the treatment of Type 2 diabetes. 相似文献
996.
Luis Ricardo Peroza Alcindo Busanello Caroline Queiroz Leal Jivago Röpke Aline Augusti Boligon Daiane Meinerz Milena Libardoni Margareth Linde Athayde Roselei Fachinetto 《Neurochemical research》2013,38(4):789-796
Classical antipsychotics can produce motor disturbances like tardive dyskinesia in humans and orofacial dyskinesia in rodents. These motor side effects have been associated with oxidative stress production in specific brain areas. Thus, some studies have proposed the use of natural compounds with antioxidant properties against involuntary movements induced by antipsychotics. Here, we examined the possible antioxidant activity of Bauhinia forficata (B. forficata), a plant used in folk medicine as a hypoglycemic, on brain lipid peroxidation induced by different pro-oxidants. B. forficata prevented the formation of lipid peroxidation induced by both pro-oxidants tested. However, it was effective against lipid peroxidation induced by sodium nitroprusside (IC50 = 12.08 μg/mL) and Fe2+/EDTA (IC50 = 41.19 μg/mL). Moreover, the effects of B. forficata were analyzed on an animal model of orofacial dyskinesia induced by long-term treatment with haloperidol, where rats received haloperidol each 28 days (38 mg/kg) and/or B. forficata decoction daily (2.5 g/L) for 16 weeks. Vacuous chewing movements (VCMs), locomotor and exploratory activities were evaluated. Haloperidol treatment induced VCMs, and co-treatment with B. forficata partially prevented this effect. Haloperidol reduced the locomotor and exploratory activities of animals in the open field test, which was not modified by B. forficata treatment. Our present data showed that B. forficata has antioxidant potential and partially protects against VCMs induced by haloperidol in rats. Taken together, our data suggest the protection by natural compounds against VCMs induced by haloperidol in rats. 相似文献
997.
Solangy Usme-Romero Milena Alonso Helena Hernandez-Cuervo Emilio J. Yunis Juan J. Yunis 《Genetics and molecular biology》2013,36(2):149-157
We analyzed the frequency of four mitochondrial DNA haplogroups in 424 individuals from 21 Colombian Amerindian tribes. Our results showed a high degree of mtDNA diversity and genetic heterogeneity. Frequencies of mtDNA haplogroups A and C were high in the majority of populations studied. The distribution of these four mtDNA haplogroups from Amerindian populations was different in the northern region of the country compared to those in the south. Haplogroup A was more frequently found among Amerindian tribes in northern Colombia, while haplogroup D was more frequent among tribes in the south. Haplogroups A, C and D have clinal tendencies in Colombia and South America in general. Populations belonging to the Chibcha linguistic family of Colombia and other countries nearby showed a strong genetic differentiation from the other populations tested, thus corroborating previous findings. Genetically, the Ingano, Paez and Guambiano populations are more closely related to other groups of south eastern Colombia, as also inferred from other genetic markers and from archeological data. Strong evidence for a correspondence between geographical and linguistic classification was found, and this is consistent with evidence that gene flow and the exchange of customs and knowledge and language elements between groups is facilitated by close proximity. 相似文献
998.
Eva Bauer Matthieu Falque Hildrun Walter Cyril Bauland Christian Camisan Laura Campo Nina Meyer Nicolas Ranc Renaud Rincent Wolfgang Schipprack Thomas Altmann Pascal Flament Albrecht E Melchinger Monica Menz Jesús Moreno-González Milena Ouzunova Pedro Revilla Alain Charcosset Olivier C Martin Chris-Carolin Sch?n 《Genome biology》2013,14(9):R103
Background
In sexually reproducing organisms, meiotic crossovers ensure the proper segregation of chromosomes and contribute to genetic diversity by shuffling allelic combinations. Such genetic reassortment is exploited in breeding to combine favorable alleles, and in genetic research to identify genetic factors underlying traits of interest via linkage or association-based approaches. Crossover numbers and distributions along chromosomes vary between species, but little is known about their intraspecies variation.Results
Here, we report on the variation of recombination rates between 22 European maize inbred lines that belong to the Dent and Flint gene pools. We genotype 23 doubled-haploid populations derived from crosses between these lines with a 50 k-SNP array and construct high-density genetic maps, showing good correspondence with the maize B73 genome sequence assembly. By aligning each genetic map to the B73 sequence, we obtain the recombination rates along chromosomes specific to each population. We identify significant differences in recombination rates at the genome-wide, chromosome, and intrachromosomal levels between populations, as well as significant variation for genome-wide recombination rates among maize lines. Crossover interference analysis using a two-pathway modeling framework reveals a negative association between recombination rate and interference strength.Conclusions
To our knowledge, the present work provides the most comprehensive study on intraspecific variation of recombination rates and crossover interference strength in eukaryotes. Differences found in recombination rates will allow for selection of high or low recombining lines in crossing programs. Our methodology should pave the way for precise identification of genes controlling recombination rates in maize and other organisms. 相似文献999.
1000.
Mariangela Rondanelli Annalisa Opizzi Simone Perna Milena Anna Faliva 《Endocrinología y nutrición》2013,60(4):197-210
Osteoporosis is a leading cause of morbidity and mortality in the elderly and influences quality of life, as well as life expectancy. Currently, there is a growing interest among the medical scientists in search of specific nutrients and/or bioactive compounds of natural origin for the prevention of disease and maintenance of bone health. Although calcium and vitamin D have been the primary focus of nutritional prevention of osteoporosis, a recent research has clarified the importance of several additional nutrients and food constituents. Based on this review of the literature, supplementation with vitamins B, C, K, and silicon could be recommended for proper maintenance of bone health, although further clinical studies are needed. The results of studies on long-chain polyunsaturated fatty acids, potassium, magnesium, copper, selenium, and strontium are not conclusive, although studies in vitro and in animal models are interesting and promising. 相似文献