ABSTRACT
Phytoremediation is a cost-effective and eco-friendly technique for the removal of heavy metal-contaminated soils and water. The less availability and mobility of heavy metals in medium decreased the efficiency of this technique. The mobility and availability of these metals in the medium can be enhanced by the addition of organic chelators. The present study was conducted to investigate the possibility of glutamic acid (GA) in improving silver (Ag) phytoextraction by sunflower (Helianthus annuus L.). Different concentrations of Ag and GA were supplied in solution form in different combinations after defined intervals. Results depicted that increasing concentration of Ag significantly reduced the plant biomass, photosynthetic pigments, and antioxidant enzyme activities (like catalase, peroxidase, ascorbate, peroxidase, superoxide dismutase). Furthermore, Ag stress increased the Ag concentration and the production of reactive oxygen species (ROS) in sunflower plants. The addition of GA alleviated the Ag-induced toxicity in plants and enhanced Ag concentration and accumulation in sunflower. The addition of GA enhanced Ag accumulation in sunflower roots by 70, 79, 58, and 66% at 0-, 100-, 250-, and 500-µM Ag treatments, respectively, as compared to control plants. In conclusion, the results showed that Ag significantly reduced the physiological and biochemical attributes in term of reduced growth of sunflower and the addition of GA alleviated the Ag induced toxicity and enhanced Ag uptake. The results suggested that sunflower can be used as hyper-accumulator plant for the removal of Ag under GA. Further studies are required to understand the role of GA at gene and microscopic level in plants.
Subject(s)
Glutamic Acid/pharmacology , Helianthus , Silver , Soil Pollutants , Soil/chemistry , Adaptation, Physiological/drug effects , Antioxidants/metabolism , Biodegradation, Environmental , Catalase/metabolism , Glutamic Acid/metabolism , Helianthus/drug effects , Helianthus/growth & development , Helianthus/metabolism , Metals, Heavy/metabolism , Metals, Heavy/toxicity , Oxidative Stress/drug effects , Peroxidase/metabolism , Photosynthesis/drug effects , Plant Roots/drug effects , Plant Roots/metabolism , Reactive Oxygen Species/metabolism , Silver/metabolism , Silver/toxicity , Soil Pollutants/metabolism , Soil Pollutants/toxicity , Superoxide Dismutase/metabolismABSTRACT
The purpose of this article is to determine prescribing rates and adherence to guidelines with regard to antipsychotic polypharmacy, high-dose prescribing, and sedative use in an outpatient population. A prospective case-note audit involving 250 consecutive attendees of an outpatient clinic was carried out. Data were analyzed using descriptive statistical methods. Differences between the groups were estimated using t test and chi(2) where applicable. Results showed that the rate of polypharmacy was 17.4%. Reasons for polypharmacy were documented in 53% of cases. High-dose antipsychotics were used in 2.5% of the monotherapy group and in 38% of the polypharmacy group. An ECG was done in 35% of patients on high-dose antipsychotic therapy. In the monotherapy group, 6.2% versus 26.5% in the polypharmacy group of patients were on at least 1 sedative or hypnotic (odds ratio [OR], 5.47; 95% confidence interval [CI], 2.02-14.82; P < .001). Forty-two percent of patients prescribed sedatives had schizophrenia spectrum disorders, and none of the patients were diagnosed with anxiety disorders. The current study confirms that despite repeated recommendations against the practice, polypharmacy rates remain consistent at the 20% level. Thorough documentation, calculating the total antipsychotic dose, and obtaining an ECG would constitute good practice.
