Heavy metal ions such as cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), and zinc (Zn) are considered essential/beneficial for optimal plant growth, development, and productivity. However, these ions readily impact functions of many enzymes and proteins, halt metabolism, and exhibit phytotoxicity at supra-optimum supply. Nevertheless, the concentrations of these heavy metal ions are increasing in agricultural soils worldwide via both natural and anthropogenic sources that need immediate attention. Considering recent breakthroughs on Co, Cu, Fe, Mn, Mo, Ni, and Zn in soil-plant system, the present paper: (a) overviews the status in soils and their uptake, transport, and significance in plants; (b) critically discusses their elevated level-mediated toxicity to both plant growth/development and cell/genome; (c) briefly cross talks on the significance of potential interactions between previous plant-beneficial heavy metal ions in plants; and (d) highlights so far unexplored aspects in the current context.

The present study investigated the effect of Arsenic (As; 5, 10, 50 μM) on protein and sugar metabolism vis-à-vis oxidative damage during early germination process and radicle emergence (at 12, 24 and 48 h stage) in Phaseolus aureus. As-exposure (50 μM) significantly enhanced protein content (by 40-60%), whereas carbohydrate content declined (by 31-44%) over that in the control. It was associated with a decline in the activities of proteases (47-53%), and increase in the activities of α- and β-amylases, starch phosphorylases, and acid invertases by 3.0, 2.6, 4.8, and 1.7 times after 48 h exposure to 50 μM As. The alteration in protein and carbohydrate metabolic machinery was also accompanied by As-induced reactive oxygen species (ROS)-mediated oxidative damage. As treatment enhanced malondialdehyde and hydrogen peroxide content by 46-252% and 23-216%, and hydroxyl and superoxide ion generation by 15-104% and 17-278%, respectively. As-induced lipid peroxidation and membrane disruption was confirmed by enhanced electrolyte leakage (by 49%) and reduced cell viability (by 43%). Furthermore, in response to 50 μM As, the activities of superoxide dismutases, catalases, ascorbate peroxidases, guaiacol peroxidases, and glutathione reductases increased by 77%, 70%, 116%, 43% and 120%, respectively, in radicles at 48 h stage over that in the control. The study concludes that As inhibits radicle emergence and elongation in germinating P. aureus seeds by altering biochemical processes related to sugar metabolism and inducing an ROS-mediated oxidative damage.

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a population of cystic fibrosis patients with more severe disease as their Shwachman scores average 66 (range 30-92). We therefore recominend routine examination of the conjunctiva for signs ofxerosis in patients with cystic fibrosis, a positive finding suggesting present or previous vitamin A deficiency at a clinical level. Positive and dubious cases should be referred to an ophthalmologist for slit-lamp examination, dark adaptometry and/or electroretinography to confirm the clinical deficiency before treatment is instituted. References 1 Underwood BA, Denning CR. Blood and liver concentrations of vitamin A and E in children with cystic fibrosis.

Unilateral microspherophakia without systemic associations is a rare condition and so is congenital palsy of the superior division of the third nerve. Here, we report both these rarities together in a 32-year-old male who had microspherophakia in his right eye and congenital palsy of the superior division of the third nerve in his left eye. The intraocular pressure (IOP) in the right eye was normal with no glaucomatous change in the fundus, but the patient had developed cataractous changes in the microspherophakia lens. The left eye of the patient had low vision due to congenital ptosis which led to stimulus deprivation amblyopia.