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11.
Jéssica Fernanda da Silva Thaise Rosa da Silva Indra Elena Costa Escobar Ana Carla Resende Fraiz Jonnathan Whiny Moraes dos Santos Tailane Ribeiro do Nascimento João Marcos Rodrigues dos Santos Samuel James Windsor Peters Roseli Freire de Melo Diana Signor Paulo Ivan Fernandes-Júnior 《World journal of microbiology & biotechnology》2018,34(12):186
Sorghum [Sorghum bicolor (L.) Moench] is a multipurpose grass cultivated in drylands due to its adaptation to drought. However the characteristics of sorghum-associated bacteria are not known in the Brazilian drylands. The aim of this study was to isolate and evaluate the plant growth promotion potential bacteria from field-grown sorghum under two irrigation and manure application levels in a Brazilian semi-arid reagion. Sorghum was irrigated with 3 or 1 mm day?1 and fertilized or not with liquid goat manure. Bacteria were obtained from surface-disinfected roots applying two nitrogen-free semi-solid media. The bacteria were evaluated for the presence of nifH gene, 16S rRNA sequences, calcium-phosphate solubilization, production of auxins and siderophores and for sorghum growth promotion. We obtained 20 out of 24 positive bacteria for nifH. The isolates were classified as in six different genera. All isolates produced auxins “in vitro”, six bacteria produced siderophores and three Enterobacteriaceae solubilized calcium-phosphate. At least ten bacteria resulted in the increased total N content in the sorghum shoots, comparable to fertilization with 50 mg N plant?1 week?1 and to inoculation with Azospirillum brasilense Ab-V5. Enterobacter sp. ESA 57 was the best sorghum plant-growth promoting bacteria isolated in this study. 相似文献
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Roseli Santos de Freitas Camila Mika Kamikawa Adriana Pardini Vicentini 《Revista iberoamericana de micología》2018,35(1):27-31
Background
Current methods for the production of Histoplasma capsulatum antigens are problematic in terms of standardization, specificity, stability, repeatability and reproducibility.Aims
In this study, we sought to optimize the methodology for producing H. capsulatum antigens, and to evaluate its applicability.Methods
Antigenic preparations obtained from 12 H. capsulatum isolates were evaluated by double immunodiffusion and immunoblotting assays against homologous and heterologous sera.Results
The evaluated and optimized protocol allowed a more stable production, as well as repeatable, reproducible, with shorter culture time and less costly. By double immunodiffusion and immunoblotting assays, the best pattern of reactivity was observed for antigens obtained with 33 days of culture from the isolates 200 and 406 against the M antigen and for the isolate 200 with 15 days against H antigen. The SDS-PAGE presented antigenic components of molecular masses between 17 and 119 kDa. The immunoblotting sensitivity was 95.5% and 100% with histoplasmosis sera from ill patients and sera from H. capsulatum infected but otherwise healthy patients, respectively, to the antigen derived from isolates 200 and 406.Conclusions
We suggest the employment of the antigen from isolate 200, with 15 or 30 days of culture, in the double immunodiffusion and immunoblotting assays due to its good ability to discriminate both sera from patients with histoplasmosis illness and histoplasmosis infection, in addition to its high specificity against heterologous sera. 相似文献13.
Mouse pleurisy induced by carrageenan is used to determine the mechanism of anti-inflammatory action of 7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2-H-1,4-benzodiazepin-2 (Ro5-4864). Pre-treatment with Ro5-4864 inhibits different inflammatory parameters, such as neutrophil influx, MPO activity and NO levels in the early phase (4 h), as well as mononuclear cells and ADA activity in the late phase (48 h) of pleurisy. dl-Aminoglutethimide, inhibitor of steroidal synthesis, reverted the effect of Ro5-4864 on these different inflammatory parameters. Our results suggest that anti-inflammatory action of Ro5-4864 may be partly due to its capacity to inhibit leukocyte migration, as well as leukocyte activation and formation of NO by a mechanism dependent on glucocorticoids. 相似文献
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Romain Nattier Philippe Grandcolas Roseli Pellens Hervé Jourdan Arnaud Couloux Simon Poulain Tony Robillard 《PloS one》2013,8(12)
The grasshopper genus Caledonula, endemic to New Caledonia, was studied to understand the evolution of species distributions in relation to climate and soil types. Based on a comprehensive sampling of 80 locations throughout the island, the genus was represented by five species, four of which are new to science, of which three are described here. All the species have limited distributions in New Caledonia. Bioclimatic niche modelling shows that all the species were found in association with a wet climate and reduced seasonality, explaining their restriction to the southern half of the island. The results suggest that the genus was ancestrally constrained by seasonality. A molecular phylogeny was reconstructed using two mitochondrial and two nuclear markers. The partially resolved tree showed monophyly of the species found on metalliferous soils, and molecular dating indicated a rather recent origin for the genus. Adaptation to metalliferous soils is suggested by both morphological changes and radiation on these soils. The genus Caledonula is therefore a good model to understand the origin of microendemism in the context of recent and mixed influences of climate and soil type. 相似文献
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Adriana Sanchez Roseli Soncini Tobias Wang Pia Koldkjaer Edwin W. Taylor Mogens L.Glass 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2001,130(4):86-687
Lungfishes (Dipnoi) occupy an evolutionary transition between water and air breathing and possess well-developed lungs and reduced gills. The South American species, Lepidosiren paradoxa, is an obligate air-breather and has the lowest aquatic respiration of the three extant genera. To study the relative importance, location and modality of reflexogenic sites sensitive to oxygen in the generation of cardio-respiratory responses, we measured ventilatory responses to changes in ambient oxygen and to reductions in blood oxygen content. Animals were exposed to aquatic and aerial hypoxia, both separately and in combination. While aerial hypoxia elicited brisk ventilatory responses, aquatic hypoxia had no effect, indicating a primary role for internal rather than branchial receptors. Reducing haematocrit and blood oxygen content by approximately 50% did not affect ventilation during normoxia, showing that the specific modality of the internal oxygen sensitive chemoreceptors is blood PO(2) per se and not oxygen concentration. In light of previous studies, it appears that the heart rate responses and the changes in pulmonary ventilation during oxygen shortage are similar in lungfish and tetrapods. Furthermore, the modality of the oxygen receptors controlling these responses is similar to tetrapods. Because the cardio-respiratory responses and the modality of the oxygen receptors differ from typical water-breathing teleosts, it appears that many of the changes in the mechanisms exerting reflex control over cardio-respiratory functions occurred at an early stage in vertebrate evolution. 相似文献
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Mouse paw oedema induced by carrageenan is used to determine if glucocorticoids are involved in the anti-inflammatory effects of peripheral benzodiazepine receptor ligands. The anti-inflammatory responses elicited by i.p. treatment with 1-(2-chlorophenyl)-N-methyl-N (1-methyl-propyl)-3-isoquinoline carboxamide (PK11195) and 7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2-H-1, 4-benzodiazepin-2 (Ro5-4864) were reversed by aminoglutethimide, an inhibitor of steroidal synthesis. Intraplantar injection into the ipsilateral paw of Ro5-4864, but not PK11195, inhibited the formation of paw oedema and this effect was reversed by aminoglutethimide. These results suggest that glucocorticoids are involved in the systemic and local anti-inflammatory effects of Ro5-4864 and only in the systemic response to PK11195. 相似文献
19.
da Silva Gomes RA Batista RP Costa de Almeida A da Fonseca DN Juliano L Hial V 《Analytical biochemistry》2003,316(1):11-14
An intramolecularly quenched fluorogenic peptide containing o-aminobenzoyl (Abz) and ethylenediamine 2,4-dinitrophenyl (Eddnp) groups at amino- and carboxyl-terminal amino acid residues, Abz-Lys-Pro-Ile-Glu-Phe-Phe-Arg-Leu-Eddnp, was hydrolyzed by purified human pepsin, gastricsin, and gastric juice uniquely at the Phe-Phe bond. Kinetic parameters determined for purified pepsin were K(m)=0.68+/-0.11 microM; k(cat)=6.3+/-0.16s(-1); k(cat)/K(m)=9.26s(-1) microM(-1); Gastricsin showed K(m)=2.69+/-0.18 microM; k(cat)=0.03+/-0.005s(-1); k(cat)/K(m)=0.011s(-1) microM(-1). Gastric juice (21 samples) from subjects without gastric disorders at endoscopy examination showed activities varying from 0.0008 to 9.72 micromolml(-1)min(-1). Pepstatin A inhibition of gastric juice enzymatic activity was complete at 3.4x10(-5)M (final concentration) inhibitor. In the proposed method the presence of a unique scissile bond in the synthetic substrate provides a direct ratio between enzymatic activity and amount of substrate hydrolyzed, and a unique step reaction facilitates the use of this assay for the determination of the activity of aspartic proteinases in biological fluids and during enzyme purification procedures. 相似文献
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Marcelo Tatit Sapienza Fabio Luiz Navarro Marques Miriam Roseli Yoshie Okamoto Fausto Haruki Hironaka Carlos Alberto Buchpiguel 《Cellular and molecular biology, including cyto-enzymology》2002,48(5):511-516
Animal models are currently used to verify the biodistribution of different radiopharmaceuticals before its clinical application in Nuclear Medicine; however, there may be some limitations. The utilization of labelled anti-tumor monoclonal antibodies (MoAb) in experimental models often requires implant of human antigens (usually a cellular implant), which cannot be achieved in immunocompetent animals. Our purpose was to label an anti-CEA MoAb with technetium-99m (99Tc) and to validate a simplified animal model using a noncellular antigenic implant. MoAb was directly labelled with 99mTc, after reduction with 2-mercaptoethanol. Labeling efficiency was checked by ascending chromatography and immunoreactive fraction was measured in plastic wells sensitized with the antigen. Radiopharmaceutical biodistribution was evaluated by dissection and scintigraphy in 5 mice groups; following the subcutaneous administration of Al(OH)3, CEA adsorbed Al(OH)2 and a control group evaluation. Labeling efficiency was 94+/-3%, which showed to be stable for 24 hr, with immunoreactive fraction above 50%. Invasive biodistribution evaluation showed prolonged blood retention, hepatic and renal uptake. A significant increase in uptake was observed in scintigraphic studies of animals with CEA-adsorbed Al(OH)3 implants compared with the other groups (p<0.05). The non-cellular antigenic implant model simplifies the pre-clinical evaluation of labelled MoAb. 相似文献