The effect of EDTA on Helianthus annuus uptake, selectivity, and translocation of heavy metals when grown in Ohio, New Mexico and Colombia soils.

The use of two EDTA concentrations for enhancing the bioavailability of cadmium, chromium, and nickel in three natural soils (Ohio, New Mexico and Colombia) was investigated. The resulting uptake, translocation and selectivity with Helianthus annuus after mobilization were also examined. In general, plants grown in the sandy-loam Ohio soil had a higher uptake that resulted in a selectivity and total metal content of Cd>Cr>>Ni and 0.73 mg and Cr>Cd>>Ni and 0.32 mg for 0.1 and 0.3 g kg-1 EDTA, respectively. With the silty-loam New Mexico soil, although the total metal uptake was not statistically different the EDTA level did alter the selectivity; Cd>Cr>>Ni (0.1 g kg-1 EDTA) and Cd>>Cr>Ni (0.3 g kg-1 EDTA). Conversely, with the Colombian (sandy clay loam) soil increasing the EDTA level resulted in a higher total metal uptake (0.62 mg) than the 0.1 g kg-1 (0.59 mg) treatment. For all three soils, the translocation of Cd was limited. Evaluating the mobile metal fraction with and without EDTA determined that the chelator was capable of overcoming mass transfer limitations associated with the expandable clay fraction in the soils. Root wash results and root biomass concentrations indicated that Cd sorption was occurring. Therefore limited Cd translocation was attributed to insufficient phytochelatin levels.

Defining a pulmonary exacerbation in cystic fibrosis.

OBJECTIVES: Despite the central importance of pulmonary exacerbations (PExs) as an outcome measure in cystic fibrosis clinical trials, no standardized definition of PEx exists. We conducted a prospective, multicenter study to establish a standardized PEx definition and score for use in clinical trials, based on clinical status rather than on treatment decisions. STUDY DESIGN: Subjects were 246 patients enrolled in the placebo arm of a randomized, controlled trial of tobramycin for inhalation. Physician-investigators completed PEx questionnaires on all subjects at scheduled intervals during the 6-month study, indicating new or worsening symptoms, physical examination findings, and impression of PEx status (presence or absence and severity). Logistic regression was used to assess the relative importance of each of the characteristics in predicting a PEx. RESULTS: We developed 2 PEx scores that use easily ascertained symptoms and chest examination findings; one also includes change in forced expiratory volume in 1 second over the preceding month. Both scores were sensitive and specific for predicting the presence of a PEx (sensitivity, 86%; specificity, 86%). The scores were validated in subjects in the intervention arm of the trial. CONCLUSION: We hope that the proposed PEx score might serve as a standardized outcome measure for future clinical trials in cystic fibrosis, allowing meaningful comparisons of study results.

Niveles de hormona de crecimiento y somatomedina C en niños con desnutrición grave / Malnutrition in children growth and somato medine C

La desnutrición se acompaña de modificaciones importantes en los niveles hormonales plasmáticos como parte de sus mecanismos adaptativos que permiten la sobrevida; devido al alto índice de desnutridos en nuestro medio, la motivación para esta investigación fue conocer como se comportan nuestros pacientes en relación a lo descrito en la literatura. Se evaluaron 20 niños desnutridos graves (13 Kwashiorkor y 7 Marasmo-Kwashiorkor) en edades comprendidas entre un mes y tres años, al ingreso, a los 15 días, al mes y a los dos meses de la recuperación. Las variables estudiadas fueron: edad, antropometría, escore de McLaren, niveles hormonales plasmáticos (Hormona de Crecimiento, IGF-1). Al ingreso los valores de hormona de crecimiento fueron elevados, disminuyendo significativamente (p<0,05) a los dos meses de la rehabilitación nutricional, en contraste los niveles de IGF-1 fueron bajos al ingreso, aumentando significativamente (p<0,05) a los dos meses de la recuperación. Los niveles altos de hormona de crecimiento pudieran ser explicados por la ausencia de retrocontrol ejercido normalmente por los niveles de IGF-1 que se encuentran disminuidos. El mejor entendimiento de los cambios hormonales en la desnutrición podrá conducir al uso terapeútico de ciertas hormonas tanto en la rehabilitación nutricional como en efermedades acompañadas de desnutrición

[Pituitary-gonadal hormonal evaluation in male patients with alcoholic liver cirrhosis]. / Evaluación hormonal hipofiso-gonadal en pacientes masculinos con cirrosis hepática alcohólica.

Pituitary-gonadal plasmatic hormonal values were measured in 26 alcoholic cirrhotic males and 20 healthy subjects. Total testosterone and luteinizing hormone mean levels were lower in the cirrhotic group (p < 0.05). Estradiol and prolactin were significant higher (p < 0.05 and p < 0.001, respectively). Follicle stimulation hormone mean values were normal. Pituitary-gonadal axis luteinizing hormone-testosterone and follicle stimulating hormone-estradiol were abnormal since the retrofeedback mechanism failed to work in each system. These results show a wide disturbance of the sexual hormonal function in our patients which certainly contributes to puzzle the complexity of the clinical and therapeutic aspects in these kind of patients.