Structural biology. Brazil network sees the light     

Vieira CL 《Science (New York, N.Y.)》2001,293(5535):1578

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Brazil. Tough placebo rules leave scientists out in the cold     

Vieira CL 《Science (New York, N.Y.)》2002,295(5553):264

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Detection of a novel hemoplasma based on 16S rRNA gene DNA in captive and free-ranging capybaras (Hydrochaeris hydrochaeris)     

Rafael F.C. Vieira  Marcelo B. Molento  Leonilda C. dos Santos  Wanderlei Moraes  Zalmir S. Cubas  Andrea P. Santos  Ana M.S. Guimaraes  Ahmed Mohamed  Ivan R. Barros Filho  Alexander W. Biondo  Joanne B. Messick 《Veterinary microbiology》2009,139(3-4):410-413

Two different species of hemoplasmas, Mycoplasma coccoides and M. haemomuris, are known to infect small rodents such as mice and rats. However, there are no previous reports of hemoplasma infection in capybara (Hydrochaeris hydrochaeris). The aim of our study was to determine whether these hemoplasmas might infect capybaras from Southern Brazil. Blood samples from 31 animals: 10 captive and 21 free-ranging capybaras were collected and packed cell volume and total plasma protein were measured. DNA was extracted and PCR assays for M. coccoides and M. haemomuris were performed. Using the M. coccoides-PCR assay 64% of the capybaras were positive, 80% free-ranging and 30% from captive animals. The prevalence of infection between the groups was significantly different (p = 0.001). Sequencing of the nearly entire 16S rRNA gene from the positive samples suggested a novel hemoplasma isolate with identity of 92% with M. coccoides and 86% with M. haemomuris. All capybara samples were negative for M. haemomuris infection. DNA of a housekeeping gene was successfully amplified from all samples. This is the first evidence of a hemoplasma infection in capybaras.  相似文献   

Anthelmintic activity of Cocos nucifera L. against sheep gastrointestinal nematodes     

L.M.B. Oliveira  C.M.L. Bevilaqua  C.T.C. Costa  I.T.F. Macedo  R.S. Barros  A.C.M. Rodrigues  A.L.F. Camurça-Vasconcelos  S.M. Morais  Y.C. Lima  L.S. Vieira  A.M.C. Navarro 《Veterinary parasitology》2009

The development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. Among these alternatives are several medicinal plants traditionally used as anthelmintics. This work evaluated the efficacy of Cocos nucifera fruit on sheep gastrointestinal parasites. The ethyl acetate extract obtained from the liquid of green coconut husk fiber (LGCHF) was submitted to in vitro and in vivo tests. The in vitro assay was based on egg hatching (EHT) and larval development tests (LDT) with Haemonchus contortus. The concentrations tested in the EHT were 0.31, 0.62, 1.25, 2.5 and 5 mg ml⁻¹, while in the LDT they were 5, 10, 20, 40 and 80 mg ml⁻¹. The in vivo assay was a controlled test. In this experiment, 18 sheep infected with gastrointestinal nematodes were divided into three groups (n = 6), with the following doses administered: G1—400 mg kg⁻¹ LGCHF ethyl acetate extract, G2—0.2 mg kg⁻¹ moxidectin (Cydectin^®) and G3—3% DMSO. The worm burden was analyzed. The results of the in vitro and in vivo tests were submitted to ANOVA and analyzed by the Tukey and Kruskal–Wallis tests, respectively. The extract efficacy in the EHT and LDT, at the highest concentrations tested, was 100% on egg hatching and 99.77% on larval development. The parameters evaluated in the controlled test were not statistically different, showing that despite the significant results of the in vitro tests, the LGCHF ethyl acetate extract showed no activity against sheep gastrointestinal nematodes.  相似文献   

Shrimp rearing in biofloc integrated with different mullet stocking densities     

Esmeralda Chamorro Legarda  Mateus Aranha Martins  Patriula Kaliana Moreira Pereira  Ramon Felipe Siqueira Carneiro  Isabela Claudiana Pinheiro  Walter Quadros Seiffert  Claudia Machado  Marco Antonio de Lorenzo  Felipe do Nascimento Vieira 《Aquaculture Research》2020,51(9):3571-3581

This work compared the effects of different densities of Mugil curema integrated in the rearing of Litopenaeus vannamei in a biofloc system on the yield and ecological performance of the system. For that, an experiment lasting 55 days was conducted. Four groups were evaluated as follows: (a) T0: shrimp reared without mullet, (b) T10: shrimp reared with 22 fish per tank, (c) T20: shrimp reared with 43 fish per tank, and (d) T30: shrimp reared with 65 fish per tank, each treatment with four replicates. The sludge:biomass ratio was higher in the T0 treatment, while the T10–T20 treatments were more efficient, producing more biomass and less sludge. The use of water was 17% more efficient in all treatments with mullet. Mullet survival was higher in the T10 and T20 treatments (mean: 84 ± 8%) than in the T30 (61 ± 5%) treatment. The fish final biomass and yield limits of the system were 0.37 kg and 3.7 kg/m³ respectively. Finally, there was no increase in the total nitrogen output of the system up to the T10 density. In conclusion, it is possible to integrate mullet up to 3.7 kg/m³, increasing the yield in 20% and decreasing water use.  相似文献   

Population structure of the critically endangered Brazilian guitarfish Pseudobatos horkelii (Rhinobatidae) revealed by double-digest restriction site-associated DNA sequencing     

Yan Torres  Matheus Marcos Rotundo  Marcelo Vianna  Patricia Charvet  Vicente Vieira Faria  Claudio Oliveira  Fausto Foresti  Vanessa Paes Cruz 《水产资源保护:海洋与淡水生态系统》2024,34(1):e4035

Evidence for new sources of NOX in the lower atmosphere     

EC Zipf  SS Prasad 《Science (New York, N.Y.)》1998,279(5348):211-213

Laboratory studies show that the reaction of short-lived O2(B3Sigmau) molecules (lifetime approximately 10 picoseconds) with N2 and the photodissociation of the N2:O2 dimer produce NOx in the stratosphere at a rate comparable to the oxidation of N2O by O(1D). This finding implies the existence of unidentified NOX sinks in the stratosphere. The NO2 observed in this experiment is isotopically heavy with a large 15N/14N enhancement. However, photodissociation of this NO2 unexpectedly produced NO molecules with a low 15N/14N ratio. The diurnal odd-nitrogen cycle in the stratosphere will be marked by a complex isotope signature that will be imprinted on the halogen and HOX catalytic cycles.  相似文献   

Autochthonous probiotic Lactobacillus sp. in the diet of bullfrog tadpoles Lithobates catesbeianus improves weight gain,feed conversion and gut microbiota          下载免费PDF全文

S.A. Pereira  G.T. Jerônimo  N. da Costa Marchiori  H.M. de Oliveira  M.S. Owatari  G.F.A. Jesus  P. Garcia  F. do Nascimento Vieira  M.L. Martins  J.L.P. Mouriño 《Aquaculture Nutrition》2017,23(5):910-916

Dietary supplementation with probiotics in animal production is an alternative to antibiotics. In frog culture, studies involving native strains of probiotic bacteria and their effects on the performance and intestinal histology of farmed animals are scarce. Therefore, this study aimed to evaluate a diet supplemented with Lactobacillus sp. in tadpoles of Lithobates catesbeianus. This randomized test was performed with two dietary treatments: non‐supplemented control diet and diet supplemented with Lactobacillus sp., with nine replications. The growth performance of Lactobacillus sp., including its bacterial enzymatic activity and stability in feed, as well as colonization and histology of the intestinal tract, was evaluated after 42 days of experimentation. Animals fed with a supplemented diet showed higher weight gain and concentration of lactic acid bacteria in the gut and lower feed conversion. No significant difference was observed in survival, total heterotrophic bacterial count or histological change in the gut between the two treatments. The Lactobacillus sp. strain was able to colonize the intestinal tract and feed and remain at a high concentration of 10⁷ and 10⁶ CFU g^?1, respectively. It produced several enzymes, which might have contributed to the greater weight gain and lower feed conversion in the supplemented animals, thus demonstrating its probiotic potential for use as a dietary supplement in bullfrog tadpoles.  相似文献   

Evaluation of Scymnus nubilus (Coleoptera: Coccinellidae) as a biological control agent against Aphis spiraecola and Cinara juniperi (Hemiptera: Aphididae)     

Roberto Meseguer Rosagro  Isabel Borges  Virgilio Vieira  Gemma Pons Sol  Antnio O Soares 《Pest management science》2020,76(2):818-826

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Water-use efficiency and evapotranspiration of mango orchard grown in northeastern region of Brazil     

Vicente de Paulo Rodrigues da Silva  Joo Hugo Baracuy da Cunha Campos  Pedro Vieira de Azevedo 《Scientia Horticulturae》2009,120(4):467-472

Knowledge of evapotranspiration (ET) and water-use efficiency (WUE) is essential in crops management mainly in arid and semiarid regions where water resources are scarce for irrigation. Field experiments were conducted at a commercial farm to obtain the WUE and ET of mango orchard growth in a semiarid environment of northeastern region of Brazil. Measurements were performed within a randomly selected experimental plot with the spacing of 10 m × 5 m between rows and plants. Soil water balance method was used to obtain the mango orchard evapotranspiration while the Penman–Monteith method (FAO/56) was used for determination reference evapotranspiration (ET_o). Soil water content was determined by six tensiometer sets installed at 0.20 m layer intervals from the soil surface down to 1.20 m soil depth. The experimental plot was irrigated with a sprinkler irrigation system based on four irrigation levels (T1 = 70%, T2 = 80%, T3 = 90% and T4 = 100% of ET_o. Results showed that ET and WUE are strongly influenced by soil water availability. Mango yield varied from a minimum value of 28.06 ton/ha in treatment T4 to a maximum value of 31.06 ton/ha in treatment T3. Such difference was found to be statistically significant (P < 0.05) by Tukey's test. Results also indicated that WUE values based on irrigation and evapotranspiration were maximum and minimum for low (treatment T1) and high (treatment T4) water levels, respectively.  相似文献