RESUMEN
Agricultural development and its associated impacts on the environment are resulting in increasingly restrictive guidelines and legislation concerning the use of chemicals in agro-ecosystems. The herbicide glyphosate is widely used for weed control in both cultivated and uncultivated areas and is considered to show low toxicity to mammals. It is highly water-soluble, and its monitoring in surface, underground, and potable waters is recommended by the United States Environmental Protection Agency. This work presents a method for the inclusion of glyphosate determination within routine anion analysis using ion chromatography in water sampler without any kind of extraction, clean-up, or preconcentration step. The equipment used was a Dionex Model ICS-3000 ion chromatograph fitted with a 25-microL loop, Ion Pac AG19 guard and AS19 analytical columns, ASRS-300 (2 mm) suppressor, and conductivity detector. The method showed a linear response to glyphosate between 0.05-0.75 mg/L with a correlation coefficient of 0.999, and a detection limit below the maximum levels permitted by Brazilian legislation. Recoveries in the range 90-105% were achieved in tests using surface, well, potable, and ultrapure water samples.
RESUMEN
The development of human clinical cytogenetics has been comparatively recent. The authors made an analytical study of chromosomes in patients presenting ocular coloboma with mental deficiency, strabismus with malformation, and other disorders in order to define the genetic aspect of these diseases. They obtained in these patients chromosomal alterations, including translocation, aneuploidies, suggesting the importance of cytogenetic analysis in eye affections even if these are considered of monogenic character.
Asunto(s)
Aberraciones Cromosómicas/genética , Coloboma/genética , Conjuntivitis/genética , Bandeo Cromosómico , Trastornos de los Cromosomas , Cromosomas Humanos 21-22 e Y , Cromosomas Humanos 6-12 y X , Humanos , Discapacidad Intelectual/genética , Cariotipificación , Estrabismo/genética , Translocación GenéticaRESUMEN
This is a study of 3 cases of the Laurence-Moon-Bardet-Biedl syndrome in two families. In one family the parents were consaguineous (first cousins). The authors studied the main symptoms and insist on the importance of the ophthalmological manifestation. No hypophyseal involvement was observed in these cases.