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131.
132.
The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected. 相似文献
133.
Denise P. Silva Gustavo Duarte Helena D.M. Villela Henrique F. Santos Phillipe M. Rosado Joo Gabriel Rosado Alexandre S. Rosado Edir M. Ferreira Adriana U. Soriano Raquel S. Peixoto 《Ecology and evolution》2019,9(9):5172-5185
Although numerous studies have been carried out on the impacts of oil spills on coral physiology, most have relied on laboratory assays. This scarcity is partly explained by the difficulty of reproducing realistic conditions in a laboratory setting or of performing experiments with toxic compounds in the field. Mesocosm systems provide the opportunity to carry out such studies with safe handling of contaminants while reproducing natural conditions required by living organisms. The mesocosm design is crucial and can lead to the development of innovative technologies to mitigate environmental impacts. Therefore, this study aimed to develop a mesocosm system for studies simulating oil spills with several key advantages, including true replication and the use of gravity to control flow‐through that reduces reliance on pumps that can clog thereby decreasing errors and costs. This adaptable system can be configured to (a) have continuous flow‐through; (b) operate as an open or closed system; (c) be fed by gravity; (d) have separate mesocosm sections that can be used for individual and simultaneous experiments; and (e) simulate the migration of oil from ocean oil spills to the nearby reefs. The mesocosm performance was assessed with two experiments using the hydrocoral Millepora alcicornis and different configurations to simulate two magnitudes of oil spills. With few exceptions, physical and chemical parameters remained stable within replicates and within treatments throughout the experiments. Physical and chemical parameters that expressed change during the experiment were still within the range of natural conditions observed in Brazilian marine environments. The photosynthetic potential (Fv/Fm) of the algae associated with M. alcicornis decreased in response to an 1% crude‐oil contamination, suggesting a successful delivery of the toxic contaminant to the targeted replicates. This mesocosm is customizable and adjustable for several types of experiments and proved to be effective for studies of oil spills. 相似文献
134.
Daniel Pereira Maria Cristina Dreher Mansur Leandro D. S. Duarte Arthur Schramm de Oliveira Daniel Mansur Pimpão Cláudia Tasso Callil Cristián Ituarte Esperanza Parada Santiago Peredo Gustavo Darrigran Fabrizio Scarabino Cristhian Clavijo Gladys Lara Igor Christo Miyahira Maria Teresa Raya Rodriguez Carlos Lasso 《Hydrobiologia》2014,735(1):15-44
Based on literature review and malacological collections, 168 native freshwater bivalve and five invasive species have been recorded for 52 hydrographic regions in South America. The higher species richness has been detected in the South Atlantic, Uruguay, Paraguay, and Amazon Brazilian hydrographic regions. Presence or absence data were analysed by Principal Coordinate for Phylogeny-Weighted. The lineage Veneroida was more representative in hydrographic regions that are poorer in species and located West of South America. The Mycetopodidae and Hyriidae lineages were predominant in regions that are richest in species toward the East of the continent. The distribution of invasive species Limnoperna fortunei is not related to species richness in different hydrographic regions there. The species richness and its distribution patterns are closely associated with the geological history of the continent. The hydrographic regions present distinct phylogenetic and species composition regardless of the level of richness. Therefore, not only should the richness be considered to be a criterion for prioritizing areas for conservation, but also the phylogenetic diversity of communities engaged in services and functional aspects relevant to ecosystem maintenance. A plan to the management of this fauna according to particular ecological characteristics and human uses of hydrographic regions is needed. 相似文献
135.
Nathália Delvaux Vanessa Duarte da Costa Maristella Matos da Costa Livia Melo Villar Henrique Sérgio Moraes Coelho Eliane Bordalo Cathalá Esberard Priscila Pollo Flores Carlos Eduardo Brand?o-Mello Cristiane Alves Villela-Nogueira Adilson José de Almeida Elisabeth Lampe 《Memórias do Instituto Oswaldo Cruz》2015,110(5):636-643
Inosine triphosphatase (ITPA) single nucleotide polymorphisms (SNPs) are stronglyassociated with protection against ribavirin (RBV)-induced anaemia in European,American and Asian patients; however, there is a paucity of data for Brazilianpatients. The aim of this study was to evaluate the ITPA SNP (rs7270101/rs1127354)frequency in healthy and hepatitis C virus (HCV)-infected patients from Brazil andthe association with the development of severe anaemia during antiviral therapy. ITPASNPs were determined in 200 HCV infected patients and 100 healthy individuals bysequencing. Biochemical parameters and haemoglobin (Hb) levels were analysed in 97patients who underwent antiviral therapy. A combination of AArs7270101+CCrs1127354(100% ITPase activity) was observed in 236/300 individuals. Anaemia was observed in87.5% and 86.2% of treated patients with AA (rs7270101) and CC genotypes (rs1127354),respectively. Men with AA (rs7270101) showed a considerable reduction in Hb at week12 compared to those with AC/CC (p = 0.1475). In women, there was no influence ofgenotype (p = 0.5295). For rs1127354, men with the CC genotype also showed a suddenreduction in Hb compared to those with AC. Allelic distribution of rs7270101 andrs1127354 shows high rates of the genotypes AA and CC, respectively, suggesting thatthe study population had a great propensity for developing RBV-induced anaemia. Aprogressive Hb reduction during treatment was observed; however, this reduction wasgreater in men at week 12 than in women. 相似文献
136.
The armored catfish Hypostomus affinis is a widespread Loricariidae fish in the Lajes Reservoir (22 degrees 42'-22 degrees 50' S; 43 degrees 53'-44 degrees 05' W), the largest lentic environment in the Rio de Janeiro State, but little is known about their reproductive biology. One hundred and twenty five females, captured from January 1996 to December 1997, were used to assess ovarian development (29 were used to determine fecundity). The oocyte distribution by size-diameter classes revealed the occurrence of two modes suggesting an asynchronic development of the ovaries. The total fecundity ranged from 1235 to 4304, averaging 2374. An exponential relationship between fecundity and total length was determined, and a direct linear relationship was found between fecundity and total weight and gonad weight. 相似文献
137.
L. D. Sette M. R. Z. Passarini C. Delarmelina F. Salati M. C. T. Duarte 《World journal of microbiology & biotechnology》2006,22(11):1185-1195
Endophytic filamentous fungi from coffee plants (Coffea arabica and C. robusta) deposited in the Brazilian Collection of Environmental and Industrial Microorganisms (CBMAI) were characterized taxonomically by using molecular tools and investigated concerning their antimicrobial activity against different human pathogenic bacteria. Thirty-seven out of 39 CBMAI strains investigated were identified to at least at genus level by ITS and rDNA D1/D2 sequencing and phylogenetic analyses. Bioactivity screening of fungal extracts against Salmonella choleraesuis (CBMAI 484), Staphylococcus aureus (CBMAI 485), Pseudomonas aeruginosa (CBMAI 489) and against four different Escherichia coli serotypes showed that 17 fungi inhibited at least one of the bacteria studied. The endophytic fungi Trichoderma harzianum (CBMAI 43), Guignardia sp. (CBMAI 69) and Phomopsis sp. (CBMAI 164) inhibited from four to five bacterial species, while five fungi were active against all pathogenic bacteria tested and were identified as Aspergillus
versicolor (CBMAI 46), Fusarium oxysporum (CBMAI 53), Glomerella sp. (CBMAI 63) and Cladosporium spp. (CBMAI 64 and CBMAI 66). The Minimal Inhibitory Concentration (MIC) for the fungus extracts varied from 0.025 to 1.0 mg ml−1, demonstrating antimicrobial potential of some of these fungi. 相似文献
138.
Francinaldo Soares Silva Jefferson Mesquita Brito Benedita Maria Costa Neta Shelre Emile Pereira Duarte Lobo 《Memórias do Instituto Oswaldo Cruz》2015,110(6):801-803
Hoover Pugedo light traps were modified for use with green and blue-light-emitting
diodes to trap phlebotomine sandflies in northeastern Brazil. A total of 2,267
specimens belonging to eight genera and 15 species were sampled. The predominant
species were Nyssomyia whitmani(34.41%) and Micropygomyia
echinatopharynx(17.25%).The green LED trap prevailed over the blue and
control lights; however, no statistically significant difference could be detected
among the three light sources. Even without statistical significance, we suggest
using LEDs as an attractant for the capture of sandflies because of several
advantages over the conventional method with incandescent lamps. 相似文献
139.
L A Gomes R Duarte D C Lima B S Diniz M L Serr?o N Labarthe 《Memórias do Instituto Oswaldo Cruz》2001,96(5):693-695
The identification of arthropod bloodmeals is important in many epidemiological studies, as, the understanding of the life cycle of vectors and the pathogens they transmit, as well as helping to define arthropods' control strategies. The precipitin test has been used for decades, but ELISA is slowly becoming more popular. To compare the two tests for sensitivity, specificity and accuracy to detect small insect bloodmeals, Aedes aegypti or Ae. fluviatilis mosquitoes were fed either on feline, canine or human hosts. Mosquitoes were frozen at 6, 12, 24, 48 or 72 h after feeding. Precipitin test showed better specificity and accuracy and ELISA test showed higher sensitivity. Better results with both tests were achieved when mosquitoes were frozen within 48 h from feeding. 相似文献
140.
Maria M. Romeiras Maria Cristina Duarte Arnoldo Santos‐Guerra Brett Jestrow Javier Francisco‐Ortega 《Curtis's Botanical Magazine》2018,35(2):166-189
Euphorbia tuckeyana is a dendroid spurge endemic to Cabo Verde. It belongs to E. subgenus Esula section Aphyllis subsection Macaronesicae, a monophyletic group of eleven species restricted to the Canaries, Madeira archipelago, the Selvagens islands, Cabo Verde, a small area of Atlantic Morocco, and Portugal, that have high horticultural potential for xeric gardens. Among them E. tuckeyana grows well in tropical environments with a summer rainy season. History of early collections and records is reviewed. The species has been previously depicted on one postage stamp and in papers focusing on the Cabo Verde flora. Three other phylogenetically distant groups of dendroid spurges, also with leaves spirally arranged in clusters located on stem tips, occur in the West Indies, Africa, and Asia. They also show high potential for tropical gardens. We present a previously unpublished ink‐drawing of E. tuckeyana that was made by the great Spanish plant illustrator Eugeni Sierra Ràfols (1919–1999). The name is lectotypified with a specimen housed in the Muséum National d'Histoire Naturelle (Paris) that was collected by the Portuguese naturalist João da Silva Feijó in the late 18th century. 相似文献