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1.
2.
Guaraná (Paullinia cupana) is a woody vine or sprawling shrub native to the central Amazon Basin. The seeds are commercially produced on some 6,000 ha in the state of Amazonas near Manaus. The principal article of commerce is an amber-colored, carbonated soft drink. It is also widely used as a high caffeine stimulant and in local medicines. The plant is monoecious and is damaged by a number of diseases, the most severe being anthracnose. Prospects are excellent for greatly expanded international markets. 相似文献
3.
M. I. Zucchi R. P. V. Brondani J. B. Pinheiro C. Brondani R. Vencovsky 《Molecular ecology resources》2002,2(4):512-513
Cagaita (Eugenia dysenterica) is a widespread plant found in the Brazilian cerrado. Its fruit is used for popular consumption and for industrial purposes. A battery of 346 primer pairs developed for Eucalyptus spp. was tested on cagaita. Only 10 primer pairs were found to be transferable between the two species. Using a polyacrilamide gel, an average of 10.4 alleles per locus was detected, in a sample of 116 individuals from 10 natural populations of cagaita. Seven polymorphic loci allowed estimation of genetic parameters, including expected average heterozigosity HE = 0.442, diversity among populations, RST = 0.268 and gene flow Nm = 0.680. 相似文献
4.
Pedro Del Bianco Benedeti Lorrayny Galoro da Silva Eduardo Marostegan de Paula Teshome Shenkoru Marcos Inácio Marcondes Hugo Fernando Monteiro Brad Amorati Yenling Yeh Simon Roger Poulson Antonio Pinheiro Faciola 《PloS one》2015,10(11)
The objective of this study was to evaluate the effects of partially replacing dry ground corn with glycerin on ruminal fermentation using a dual-flow continuous culture system. Six fermenters (1,223 ± 21 ml) were used in a replicated 3x3 Latin square arrangement with three periods of 10 d each, with 7 d for diet adaptation and 3 d for sample collections. All diets contained 75% concentrate and three dietary glycerin levels (0, 15, and 30% on dry matter basis), totaling six replicates per treatment. Fermenters were fed 72 g of dry matter/d equally divided in two meals/d, at 0800 and 2000 h. Solid and liquid dilution rates were adjusted daily to 5.5 and 11%/h, respectively. On d 8, 9, and 10, samples of 500 ml of solid and liquid digesta effluent were mixed, homogenized, and stored at -20°C. Subsamples of 10 ml were collected and preserved with 0.2 mL of a 50% H2SO4 solution for later determination of NH3-N and volatile fatty acids. Microbial biomass was isolated from fermenters for chemical analysis at the end of each experimental period. Data were analyzed using the MIXED procedure in SAS with α = 0.05. Glycerin levels did not affect apparent digestibility of DM (P
Lin. = 0.13; P
Quad. = 0.40), OM (P
Lin. = 0.72; P
Quad. = 0.15), NDF (P
Lin. = 0.38; P
Quad. = 0.50) and ADF (P
Lin. = 0.91; P
Quad. = 0.18). Also, glycerin inclusion did not affect true digestibility of DM (P
Lin. = 0.35; P
Quad. = 0.48), and OM (P
Lin. = 0.08; P
Quad. = 0.19). Concentrations of propionate (P < 0.01) and total volatile fatty acids (P < 0.01) increased linearly and concentrations of acetate (P < 0.01), butyrate (P = 0.01), iso-valerate (P < 0.01), and total branched-chain volatile fatty acids, as well as the acetate: propionate ratio (P < 0.01) decreased with glycerin inclusion. Linear increases on NH3-N concentration in digesta effluent (P < 0.01) and on NH3-N flow (P < 0.01) were observed due to glycerin inclusion in the diets. Crude protein digestibility (P = 0.04) and microbial N flow (P = 0.04) were greater in the control treatment compared with the other treatments and responded quadratically with glycerin inclusion. Furthermore, the inclusion of glycerin linearly decreased (P = 0.02) non-ammonia N flow. Glycerin levels did not affect the flows of total N (P
Lin. = 0.79; P
Quad. = 0.35), and dietary N (P
Lin. = 0.99; P
Quad. = 0.07), as well as microbial efficiency (P
Lin. = 0.09; P
Quad. = 0.07). These results suggest that partially replacing dry ground corn with glycerin may change ruminal fermentation, by increasing total volatile fatty acids, and propionate concentration without affecting microbial efficiency, which may improve glucogenic potential of beef cattle diets. 相似文献
5.
6.
Alves Leticia Rodrigues Rossatto Davi Rodrigo Rossi Mônica Lanzoni Martinelli Adriana Pinheiro Gratão Priscila Lupino 《Protoplasma》2020,257(2):597-605
Protoplasma - The application of Se to plants growing under Cd contamination may become an alternative strategy to minimize Cd damage. However, there is no specific information available regarding... 相似文献
7.
Polarized epithelial cells convert into migratory invasive cells during a number of developmental processes, as well as when tumors metastasize. Much has been learned recently concerning the molecules and mechanisms that are responsible for generating and maintaining epithelial cell polarity. However, less is known about what becomes of epithelial polarity proteins when various cell types become migratory and invasive. Here, we report the localization of several apical epithelial proteins, Par-6, Par-3/Bazooka and aPKC, during border cell migration in the Drosophila ovary. All of these proteins remained asymmetrically distributed throughout migration. Moreover, depletion of either Par-6 or Par-3/Bazooka by RNAi resulted in disorganization of the border cell cluster and impaired migration. The distributions of several transmembrane proteins required for migration were abnormal following Par-6 or Par-3/Bazooka downregulation, possibly accounting for the migration defects. Taken together, these results indicate that cells need not lose apical/basal polarity in order to invade neighboring tissues and in some cases even require such polarity for proper motility. 相似文献
8.
Paula Zaghetto Almeida Josana Maria Messias Marita Gimenez Pereira Vanessa Elisa Pinheiro Lummy Maria Oliveira Monteiro Paulo Ricardo Heinen 《Biocatalysis and Biotransformation》2018,36(5):389-395
Starch has great importance in human diet, since it is a heteropolymer of plants, mainly found in roots, as potato, cassava and arrowroots. This carbohydrate is composed by a highly-branched chain: amylopectin; and a linear chain: amylose. The proportion between the chains varies according to the botanical source. Starch hydrolysis is catalyzed by enzymes of the amilolytic system, named amylases. Among the various enzymes of this system, the glucoamylases (EC 3.2.1.3 glucan 1,4-alpha-glucosidases) are the majority because they hydrolyze the glycosidic linkages at the end of starch chains releasing glucose monomers. In this work, a glucoamylase secreted in the culture medium, by the ascomycete Aspergillus brasiliensis, was immobilized in Dietilaminoetil Sepharose-Polyethylene Glycol (DEAE-PEG), since immobilized biocatalysts are more stable in long periods of hydrolysis, and can be recovered from the final product and reused for several cycles. Glucoamylase immobilization has shown great thermal stability improvement over the soluble enzyme, reaching 66% more activity after 6?h at 60?°C, and 68% of the activity after 10 hydrolysis cycles. A simplex centroid experimental mixture design was applied as a tool to characterize the affinity of the immobilized enzyme for different starchy substrates. In assays containing several proportions of amylose, amylopectin and starch, the glucoamylase from A. brasiliensis mainly hydrolyzed the amylopectin chains, showing to have preference by branched substrates. 相似文献
9.
Dorothy Koveal Anderson S. Pinheiro Wolfgang Peti Rebecca Page 《Biomolecular NMR assignments》2011,5(1):39-41
The backbone and side chain resonance assignments of the murine KSR1 CA1 domain have been determined based on triple-resonance
experiments using uniformly [13C, 15N]-labeled protein. This assignment is the first step towards the determination of the three-dimensional structure of the
unique KSR1 CA1 domain. 相似文献
10.
C. C. Marques A. C. Nunes T. Pinheiro P. A. Lopes M. C. Santos A. M. Viegas-Crespo M. G. Ramalhinho M. L. Mathias 《Biological trace element research》2006,109(1):75-89
Time-dependent effects of lead (Pb) toxicity were studied in Algerian mice (Mus spretus) treated with Pb acetate via drinking water (1 g Pb acetate/L) for different periods of exposure (15, 45, and 90 d). End
points included the determination of hepatic Pb concentration and the assessment of some morphophysiological, biochemical
and cytogenetical parameters. A control group receiving distilled water was also monitored for comparative purposes. Hepatic
Pb accumulation increased with the time of exposure and was significantly higher in treated mice when compared to controls.
In association with significant body mass loss in Pb-exposed mice, for 15 and 45 d, a significant increase in the relative
spleen mass was observed after 45 d of intoxication. Pb-exposed mice also showed significant decreases in red blood cells,
hematocrit, and mean corpuscular hemoglobin. On the contrary, changes in plasma transferases (aspartate aminotransferase and
alanine aminotransferase) and hepatic superoxide dismutase activities did not reach statistical significance. A significant
increase in the frequency of micronucleated polychromatic bone marrow erythrocytes was also found in the 90-d-exposed mice,
compared to nontreated mice and the other exposed groups. Exposure to Pb acetate resulted also in a slight time-dependent
decrease of the polychromatic-normochromatic ratio. These results support the concept that a long-term chronic exposure to
Pb induced alterations upon some morphophysiological and genetic paramaters in Algerian mice. 相似文献