Genotyping of Streptococcus agalactiae strains isolated from fish,human and cattle and their virulence potential in Nile tilapia     

U.P. Pereira  G.F. Mian  I.C.M. Oliveira  L.C. Benchetrit  G.M. Costa  H.C.P. Figueiredo 《Veterinary microbiology》2010,140(1-2):186-192

Streptococcus agalactiae (Lancefield group B; GBS) is a pathogen that causes meningoencephalitis in fish, mastitis in cows, and neonatal sepsis in humans. The objective of this study was to characterize S. agalactiae isolated from fish (n = 27), cows (n = 9), and humans (n = 10) using pulsed-field gel electrophoresis (PFGE) and to investigate the virulence of the identified strains in Nile tilapia (Oreochromis niloticus). The PFGE types were determined by dendogram analyses and the in vivo virulence was evaluated by experimental infection (using i.p. and immersion routes) of Nile tilapia. Among the fish strains, 5 different PFGE patterns were observed and 21 strains showed the same genetic pattern. In some farms two or three profiles occurred simultaneously. The bovine and human strains exhibited high genetic diversity and few relationships were established among S. agalactiae strains from the three host origins analyzed. Eight S. agalactiae strains from fish caused high mortality of Nile tilapia. Three bovine strains infected Nile tilapia (by i.p. route) and two of those strains caused clinical signs of meningoencephalitis. All human strains (n = 5) infected Nile tilapia (by i.p. route) and meningoencephalitis was induced by one strain (by both i.p. and immersion routes). In conclusion, the analyzed strains from the three natural hosts did not show genetic relatedness, yet some of the bovine and human strains were able to infect fish and cause meningoencephalitis. We suggest that genetic linkage is not a prerequisite for S. agalactiae to cross the host-specific barrier.  相似文献   

Polymorphic microsatellite marker set for <Emphasis Type="Italic">Carica papaya</Emphasis> L. and its use in molecular-assisted selection     

Eder Jorge de Oliveira  Aline dos Santos Silva  Fabiana Moraes de Carvalho  Lucas Ferraz dos Santos  Juliana Leles Costa  Vanusia Batista de Oliveira Amorim  Jorge Luiz Loyola Dantas 《Euphytica》2010,173(2):279-287

Conventional methods for the selection of papaya pure lines are time-consuming. Procedures involving the use of molecular markers and the indirect selection of homozygous plants can reduce this time considerably. The objective of this study was to evaluate the informativeness of a microsatellite marker set when used in marker-assisted selection (MAS) for the development of new papaya lines. Eighty-three lines originating from two segregating F₃ populations and from papaya germplasm were used for the molecular analysis of 27 microsatellite primers. Twenty polymorphic microsatellite primers were identified, allowing the identification of 86 alleles, with an average of 3.18 alleles per primer. The observed heterozygosity values were low for both the markers (0.00–0.29) and the individual lines (0.00–0.35). The inbreeding coefficient (f) ranged from 0.634 to 1.00. Eleven lines with f = 1.00 and 18 lines with f varying from 0.953 to 0.961 were identified. In addition, papaya lines showed high genetic diversity, which will certainly contribute to the development of new varieties. Our results show that the use of microsatellites in MAS is a quick and effective procedure for the development of papaya lines.  相似文献   

Potential of the electronic-nose for the diagnosis of bacterial and fungal diseases in fruit trees     

F. Spinelli  M. Noferini  J. L. Vanneste  G. Costa 《EPPO Bulletin》2010,40(1):59-67

The electronic-nose instrumentation has advanced rapidly during the past decade, as the need for highly sensitive, fast and accurate analytical measurements have considerably stimulated the interest in developing these sensors as diagnostic tools. Given that the pathogen-induced plant responses also include changes in emission of volatiles, the electronic-nose may represent a powerful and operator-friendly alternative for rapid and reliable screening of asymptomatic plant material. In the present study, the electronic nose EOS⁸³⁵ (Sacmi, Imola, Italy), based on metal oxide semiconductors, was used. EOS⁸³⁵ was able to detect asymptomatic apple and pear plants experimentally infected with Erwinia amylovora (fire blight). The electronic nose was also successfully tested for discriminating Botrytis and Sclerotinia rots on both green and yellow kiwifruits. Even if the electronic-nose can be successfully used in experimental conditions for early diagnosis of both pre- and post-harvest diseases, its practical application in open fields, nurseries and packing houses still requires further studies.  相似文献   

Emergent Sources of Prebiotics: Seaweeds and Microalgae     

Maria Filomena de Jesus Raposo  Alcina Maria Miranda Bernardo de Morais  Rui Manuel Santos Costa de Morais 《Marine drugs》2016,14(2)

In recent years, scientists have become aware that human microbiota, in general, and gut microbiota, in particular, play a major role in human health and diseases, such as obesity and diabetes, among others. A large number of evidence has come to light regarding the beneficial effects, either for the host or the gut microbiota, of some foods and food ingredients or biochemical compounds. Among these, the most promising seem to be polysaccharides (PS) or their derivatives, and they include the dietary fibers. Some of these PS can be found in seaweeds and microalgae, some being soluble fibers, such as alginates, fucoidans, carrageenans and exopolysaccharides, that are not fermented, at least not completely, by colonic microbiota. This review gives an overview of the importance of the dietary fibers, as well as the benefits of prebiotics, to human health. The potential of the PS from marine macro- and microalgae to act as prebiotics is discussed, and the different techniques to obtain oligosaccharides from PS are presented. The mechanisms of the benefits of fiber, in general, and the types and benefits of algal fibers in human health are highlighted. The findings of some recent studies that present the potential effects of prebiotics on animal models of algal biomass and their extracts, as well as oligo- and polysaccharides, are presented. In the future, the possibility of using prebiotics to modulate the microbiome, and, consequently, prevent certain human diseases is foreseen.  相似文献   

Histological and antioxidant responses in Rhamdia quelen sedated with propofol          下载免费PDF全文

Luciane Tourem Gressler  Fernando Jonas Sutili  Luiza Loebens  Etiane Medianeira Hundertmark Saccol  Tanise Silva Pês  Taylise Vey Parodi  Sílvio Teixeira da Costa  Maria Amália Pavanato  Bernardo Baldisserotto 《Aquaculture Research》2016,47(7):2297-2306

Morphometry of gills and antioxidant/oxidant status in gills, brain, liver and blood of Rhamdia quelen sedated with propofol were studied. The purpose was to investigate structural and functional responses upon administration of the drug in order to validate its use for the species. The fish were exposed to 0, 0.4 or 0.8 mg L^?1 propofol for 1, 6 or 12 h, which are times normally used in live fish transport. Propofol induced an increase in chloride cell in the non‐respiratory epithelium of the gill. Standard biochemical assays (thiobarbituric acid reactive substances and lipid hydroperoxides) indicated that the lowest concentration of propofol did not induce lipoperoxidation in gills, brain, liver or blood. The oxidative status of enzymatic (catalase, superoxide dismutase and glutathione‐S‐transferase) and non‐enzymatic (non‐protein thiols) antioxidants differed among the tested sites. Apart from the blood, superoxide dismutase was the enzyme to show the highest activity in the presence of propofol, which is known to possess antioxidant properties that resemble those of vitamin E. The absence of chloride cells in the respiratory epithelium (lamella) in association with the stability of the lamellar structure (i.e. lamellar area, total height of lamella and width of lamella) indicate that ion and oxygen uptake were preserved under propofol sedation. Thus, 0.4 mg L^?1 propofol should be considered to sedate R. quelen during lengthy procedures, such as transport, for it was able to maintain ionic and respiratory homeostasis as well as prevent peroxidative damage in vital organs.  相似文献   

Marine ornamental fish imports in the European Union: an economic perspective          下载免费PDF全文

Miguel Costa Leal  Marcela Carraro Melo Vaz  João Puga  Rui Jorge Miranda Rocha  Chris Brown  Rui Rosa  Ricardo Calado 《Fish and Fisheries》2016,17(2):459-468

The marine ornamental fish trade (MOFT) is a worldwide industry that targets a remarkable quantity and diversity of reef fish species and provides an important source of revenue for exporting countries, particularly developing nations in Southeast Asia. Here we provide, for the first time, an economic assessment of the MOFT to the European Union (EU), one of the key players of the marine aquarium trade, along with the USA and Japan. Data from EUROSTAT (the European Statistical System) was analysed for the MOFT between 2000 and 2011. Results show that this industry was not affected by the economic crisis and accounted for a total of 135 million Euros during the study period. Both the UK and Indonesia have been reinforcing their importance as leading importer and exporter countries, respectively. The long‐term temporal pattern of the MOFT by EU and non‐EU countries is described, as well as its diversity and evenness between importing and exporting countries. The present economic assessment also identifies the key players of this industry, and ultimately contributes to management and conservation practices that may enhance the sustainable use of world's coral reefs.  相似文献   

Anthelmintic activity of Cocos nucifera L. on intestinal nematodes of mice     

C.T.C. Costa  S.M. Morais  A.L.F. Camurça-Vasconcelos  M.V. Maciel  R.R. Braga  L.M.B. Oliveira 《Research in veterinary science》2010,88(1):101-103

In this study, we evaluated the anthelmintic activity of the liquid extracted from the bark of the green coconut (LBGC), as well as butanol extract obtained from LBGC, on mouse intestinal nematodes. Thirty-six naturally infected mice were distributed into six groups receiving the following treatments: Group I: 1000 mg/kg of LBGC; Group II: 2000 mg/kg of LBGC; Group III: 500 mg/kg of butanol extract; Group IV: 1000 mg/kg of butanol extract; Group V: 0.56 mg/kg febendazole; and Group VI: 3% dimethylsulfoxide. The chemical composition of the LBGC and its butanol extract was determined by phytochemical tests. A dose of 1000 mg/kg of butanol extract had 90.70% efficacy in reducing the mouse worm burden (p < 0.05). Phytochemical tests revealed the presence of triterpens, saponnins and condensed tannins in the LBGC and butanol extracts. These results suggest that Cocos nucifera extracts may be useful in the control of intestinal nematodes.  相似文献   

Seroprevalence of and risk factors for Toxoplasma gondii in sheep raised in the Jaboticabal microregion, São Paulo State, Brazil     

Welber Daniel Zanetti Lopes  Thaís Rabelo dos Santos  Ricardo dos Santos da Silva  Walter Matheus Rossanese  Fernando Augusto de Souza  Joana D’Ark de Faria Rodrigues  Rafael Paranhos de Mendonça  Vando Edésio Soares  Alvimar José da Costa 《Research in veterinary science》2010,88(1):104-106

Seroprevalence of and risk factors for toxoplasmosis in sheep from different properties in the Jaboticabal microregion, São Paulo State, Brazil were determined. Antibodies to Toxoplasma gondii were found in sera of 52.0% of 488 sheep tested by indirect fluorescent antibody test (IFAT ? 64). T. gondii seropositivity in sheep was significantly associated with gender of the sheep, pasturing system, contact with cats, and the use of mineral supplements and the type of feed.  相似文献   

Active Versus Passive Biomonitoring of Air Quality: Genetic Damage and Bioaccumulation of Trace Elements in Flower Buds of Tradescantia pallida var. purpurea     

Gustavo Marques da Costa  Camila Tamires Petry  Annette Droste 《Water, air, and soil pollution》2016,227(7):229

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Molecular characterization of accessions of a rare genetic resource: sugary cassava (Manihot esculenta Crantz) from Brazilian Amazon     

Elisa Ferreira Moura  Nelcimar Reis Sousa  Mônika Fecury Moura  Miguel Costa Dias  Everton Diel Souza  João Tomé de Farias Neto  José Edson Sampaio 《Genetic Resources and Crop Evolution》2016,63(4):583-593

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