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71.
Dentinho MT Moreira OC Pereira MS Bessa RJ 《Animal : an international journal of animal bioscience》2007,1(5):645-650
Cistus ladanifer L. (CL) is a perennial shrub abundant in dry woods and dry land of Mediterranean zone, with high level of tannins. Tannins bind to protein, preventing its degradation in the digestive compartments. This tannin/protein complex may be advantageous when partially protecting good-quality feed protein from excessive rumen protein degradation. The objective of this trial was to use a CL phenol crude extract to prevent excessive rumen degradation of soya-bean meal protein. The phenolic compounds were extracted using an acetone/water solution (70:30, v/v). Soya-bean meal was then treated with this crude CL extract, containing 640 g of total phenols (TP) per kg of dry matter (DM), in order to obtain mixtures with 0, 12.5, 25, 50, 100 and 150 g of TP per kg DM. Three rumen-cannulated rams were used to assess in sacco rumen degradability of DM and nitrogen (N). The three-step in vitro procedure was used to determine intestinal digestibility. Increasing extract concentrations quadratically decreased the N-soluble fraction a (R2 = 0.96, P = 0.0001) and increased the non-soluble degradable fraction b (R2 = 0.92, P = 0.005). The rate of degradation c linearly decreased with CL extract doses (R2 = 0.44, P = 0.0065). For the effective rumen degradability of N, a linear reduction (R2 = 0.94, P < 0.0001) was observed. The in vitro intestinal digestibility of protein (ivID) quadratically decreased (R2 = 0.99, P < 0.0001) with TP inclusion and the rumen undegradable protein (RUP) showed a quadratic increase (R2 = 0.94, P = 0.0417). Total intestinal protein availability, computed from the RUP and ivID, linearly decreased with TP inclusion level (R2 = 0.45, P = 0.0033). 相似文献
72.
Gene flow from transgenic to nontransgenic soybean plants in the Cerrado region of Brazil 总被引:1,自引:0,他引:1
Abud S de Souza PI Vianna GR Leonardecz E Moreira CT Faleiro FG Júnior JN Monteiro PM Rech EL Aragão FJ 《Genetics and molecular research : GMR》2007,6(2):445-452
Evaluation of transgenic crops under field conditions is a fundamental step for the production of genetically engineered varieties. In order to determine if there is pollen dispersal from transgenic to nontransgenic soybean plants, a field release experiment was conducted in the Cerrado region of Brazil. Nontransgenic plants were cultivated in plots surrounding Roundup Ready transgenic plants carrying the cp4 epsps gene, which confers herbicide tolerance against glyphosate herbicide, and pollen dispersal was evaluated by checking for the dominant gene. The percentage of cross-pollination was calculated as a fraction of herbicide-tolerant and -nontolerant plants. The greatest amount of transgenic pollen dispersion was observed in the first row, located at one meter from the central (transgenic) plot, with a 0.52% average frequency. The frequency of pollen dispersion decreased to 0.12% in row 2, reaching 0% when the plants were up to 10 m distance from the central plot. Under these conditions pollen flow was higher for a short distance. This fact suggests that the management necessary to avoid cross-pollination from transgenic to nontransgenic plants in the seed production fields should be similar to the procedures currently utilized to produce commercial seeds. 相似文献
73.
Doriguetto AC Martins FT Ellena J Salloum R dos Santos MH Moreira ME Schneedorf JM Nagem TJ 《化学与生物多样性》2007,4(3):488-499
The crystal structure of '2,2',4-trihydroxybenzophenone' (=(2,4-dihydroxyphenyl)(2-hydroxyphenyl)methanone; 1) was determined, and its molecular structure, along with intra- and intermolecular H-bonds, was analyzed. The anti-inflammatory potential of 1, evaluated by means of the rat-paw-edema assay, with carrageenan as inflammation stimulus, was found to be similar high as that of indomethacin. In contrast, benzophenone proper (2) was hardly active in this assay. Our results indicate that these anti-inflammatory effects are related to the action of kinins and prostaglandins. The radical-scavenging properties of 1 towards DPPH were found to be similar as those of typical phenolics, but somewhat lower than that of ascorbic acid. The structure-activity relationship (SAR) of 1 is discussed. 相似文献
74.
75.
Srgio Henrique Borges Fabricio Baccaro Marcelo Moreira Erik Lacerda Choueri 《Biotropica》2019,51(6):903-912
The principles of island biogeography are rarely applied to the animal assemblages of Amazonian river islands. Here, we compare bird assemblages of Amazonian river islands with a variety of mainland habitats. We also examine how bird species diversity and composition are related to island physical attributes. Birds were sampled with mist nets and qualitative censuses on 11 river islands and 24 mainland sites on the lower reaches of the Rio Negro in the Brazilian Amazon. Island bird assemblages were characterized by lower species richness and a higher abundance of a few dominant species. Additionally, the species composition of the islands was distinct from that of the mainland, including the nearby floodplain habitats. The number of bird species increased with island size and habitat diversity, and decreased with degree of isolation. In addition, small islands tended to harbor an impoverished subset of the species present on larger ones. Bird species diversity and composition on Amazonian river islands are likely influenced by the ecological succession and historical events affecting island formation. Considering their small total area across the Amazon basin, these insular fluvial communities could be disproportionately threatened by river channel disturbances related to climate change or hydroelectric dam development. Abstract in Portughese is available with online material. 相似文献
76.
Taciana S. do Carmo Felipe S. Moreira Bruna V. Cabral Raquel C. C. Dantas Vicelma L. Cardoso 《Geomicrobiology journal》2019,36(3):195-203
In this paper, we are presenting a biological process to recover phosphorus by solubilizing low-grade phosphate rocks. To this end, the efficiency of different phosphate-solubilizing microorganism (PSM) species for solubilizing P from phosphate rocks using both pure cultures and associations. Nutritional conditions, phosphate rock concentrations, and reactor designs were tested. The genus Bacillus, especially Bacillus megaterium (ATCC 14581), was found to be the most promising PSM for solubilizing P. Production of organic acids and acidic pH values were shown to be directly related to P solubilizing. However, associations between tested microorganisms did not significantly enhance process efficiency. We conclude that nutritional factors of the medium are important to solubilization, and lower phosphate rock concentrations lead to better solubilization. The Air Lift reactor was promising for B. megaterium (ATCC 14581), but adaptations are needed for further tests. 相似文献
77.
Rodrigo Fortes-Silva Fabiola De Oliveira Paes Leme Túlio Pacheco Boaventura Helena Corrêa Pinto De Mendonça Jane Prado Leite Moreira Pedro Hugo Henriques Cunha 《Chronobiology international》2019,36(2):276-287
The aim of this study was to investigate the daily rhythms of hematological, biochemical and enzymatic parameters of the blood of a nocturnal model of fish (Lophiosilurus alexandri) bred in the laboratory (F1). Thirty-six juveniles were stocked in six tanks of a recirculation aquaculture system for 20 days. The fish were exposed to a light:dark cycle of 12:12 h and were fed 1% of biomass twice a day with commercial diet. The daily rhythms of hematological, biochemical and enzymatic parameters were then measured at six sampling times “zeitgeber time = ZT” at four-hour intervals under light:dark 12:12 h (lights on = ZT0, at 8.00 a.m). No differences were observed to alkaline phosphatase, glucose, cortisol, aspartate aminotransferase, superoxide dismutase, total protein and hematocrit (p > 0.05). However, white blood cell count, Lymphocytes (LYN), Neutrophils (NEU), Eosinophil and Neutrophils to Lymphocytes ratio were significant different between sample times (p < 0.05). Also, a significant difference in alanine transaminase was observed, with a peak of production at nighttime. In contrast, glutathione peroxidase peaked at 8:00. Uric acid, magnesium and Calcium (Ca++) showed statistically significant differences (p < 0.05). A significant difference was observed (p < 0.05), with a peak of albumin at 08:00 and triglycerides at 12:00, while cholesterol was low (p < 0.05) at 08:00 and higher from 12:00 to 04:00. Cosinor analysis revealed also rhythmicity to SOD, UA, Mg and Ca++, ALB and CHO (p < 0.05). In conclusion, the time of day must be considered a key factor when using blood parameters as biomarkers for disease, health and welfare in the L. alexandri aquaculture. 相似文献
78.
Marcelo Massa Alexandre Moreira Renato A. Costa Marcelo R. Lima Carlos R. Thiengo Walter Q. Marquez Aaron J. Coutts Marcelo S. Aoki 《Biology of sport / Institute of Sport》2022,39(2):435
This study examined the influence of birth date, salivary testosterone [sT] concentration, sexual maturity status, and general strength on the selection process of an elite Brazilian soccer club during a 12-month period, which was a 2nd phase of a 24-month selection process. The stature, body mass, sT, sexual maturity status [Tanner scale], and hand grip strength were assessed for 143 players during 2 weeks. From these 143 players, 100 players were dismissed [DIS] and 43 players were selected to integrate the club’s under-14 squad. Following 1-year training period, the under-14 team was assembled with 9 players designated as starters [STA], and then, comparisons were conducted taking into account a group of non-starters (selected; SEL = 34 players) and STA (n = 09). The DIS, SEL, STA players, and reference population, were compared for birth distribution. A greater proportion of players was born in the first trimester in the STA [75.0%], SEL [57.1%] and DIS [50.0%] groups compared to the reference population [25.8%]. One-way ANOVA showed a higher sT for STA group [516.0 ± 129.9 pmol·L-1], compared to SEL [415.5 ± 117.9 pmol·L-1] and DIS groups [390.9 ± 84.9 pmol·L-1; p = 0.003), and Kruskall-Wallis test showed a higher gonadal development for STA compared to DIS [p = 0.001]. The current findings suggest a strong influence of birth date and biological maturation on young soccer players selection process. Soccer coaches should consider these influences when making decisions about player selection of elite youth players. 相似文献
79.
Manuela G. Neuman Helmut K. Seitz Rolf Teschke Stephen Malnick Kamisha L. Johnson-Davis Lawrence B. Cohen Anit German Nicolas Hohmann Bernhardo Moreira George Moussa Mihai Opris 《Current issues in molecular biology》2022,44(3):1294
Hepatic cells are sensitive to internal and external signals. Ethanol is one of the oldest and most widely used drugs in the world. The focus on the mechanistic engine of the alcohol-induced injury has been in the liver, which is responsible for the pathways of alcohol metabolism. Ethanol undergoes a phase I type of reaction, mainly catalyzed by the cytoplasmic enzyme, alcohol dehydrogenase (ADH), and by the microsomal ethanol-oxidizing system (MEOS). Reactive oxygen species (ROS) generated by cytochrome (CYP) 2E1 activity and MEOS contribute to ethanol-induced toxicity. We aimed to: (1) Describe the cellular, pathophysiological and clinical effects of alcohol misuse on the liver; (2) Select the biomarkers and analytical methods utilized by the clinical laboratory to assess alcohol exposure; (3) Provide therapeutic ideas to prevent/reduce alcohol-induced liver injury; (4) Provide up-to-date knowledge regarding the Corona virus and its affect on the liver; (5) Link rare diseases with alcohol consumption. The current review contributes to risk identification of patients with alcoholic, as well as non-alcoholic, liver disease and metabolic syndrome. Additional prevalence of ethnic, genetic, and viral vulnerabilities are presented. 相似文献
80.