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Copyright of Revista Ambiente e Água is the property of Revista Ambiente e Agua and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soybean represents a valuable source of food for humans and animals and the quality of the seeds has great importance for the establishment and high productivity of this crop. Soybean seeds require continuous improvement, which is dependent on a better understanding of the regulatory mechanisms that coordinate seed germination. To investigate whether the method of water absorption into soybean seeds could lead to abnormal seedlings, and if this could be associated with cytogenetical consequences, we premoistened the seeds of three cultivars; M 6410 IPRO, M6210 IPRO, and BMX Potência RR by direct immersion (fast method), use of a wet substrate (intermediate method), and by moist atmosphere (slow method) with distilled water at 25°C for 24 hours. We investigated the normal and abnormal seedlings, electrical conductivity, mitosis, cell death, and the chromosomal abnormalities index. The comet assay was applied to investigate DNA fragmentation. Direct immersion in water induced seedling growth inhibition and caused cytological alterations associated with genotoxicity effects in the studied soybean genotypes. Slow premoistening of the seeds increased seedling performance as a result of higher final germination percentage (above 85%), reduced abnormal seedlings (below 5%, on average), and reduced the electrical conductivity of seeds. All three genotypes of soybean seeds lost their ability to withstand the imbibitional damage induced by direct immersion as abnormal seedlings increased. We concluded that the fast water absorption by seeds poses a threat to genomic integrity owing to its potential for genotoxicity to DNA, manifesting as breaks or loss of whole chromosomes. Slow premoistening of the seeds resulted in a longer time period to deal with damage. Stabilized seedling growth was provided by altering cytogenetic responses during uptake of water by soybean seeds through the maintenance of cell viability. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ambiente e Água is the property of Revista Ambiente e Agua and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: The indiscriminate use of antimicrobials has selected for the emergence of resistant strains. Many mechanisms contribute to the spread of antimicrobial-resistant genes, and integrons play a key role in this process. The aim of this study was to describe the serotypes and resistance profiles, and to characterize the presence of integrons in Salmonella strains isolated from Dourados, Mato Grosso do Sul, Brazil. Methodology: Thirty-six isolates from different sources were used. To evaluate the resistance profiles, the determination of minimum inhibitory concentrations together with polymerase chain reaction were used to screen for the presence of class 1 and class 2 integrons. Results: The Infantis serotype of Salmonella was the most frequently isolated serotype. Minimum inhibitory concentrations showed that out of the 36 isolates, 11 (30.5%) were resistant to all the antimicrobials tested. These resistant isolates were separated into three groups: 4 clinical isolates (36.4%), 3 food isolates (36.4%), and 4 water isolates (27.2%). Class 1 integrons occurred in 31 (86.1%) isolates and were found in all 11 resistant isolates (35.5 %) and in 20 (64.5%) of the non-resistant isolates. Class 2 integrons were found in 3 (8.3%) isolates, which were all non-resistant. Conclusion: The presence of an integron did not necessarily confer resistance. Future studies will seek to identify the mechanism behind integron-mediated antimicrobial resistance. [ABSTRACT FROM AUTHOR]