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Micronutrient Status of Soils and Crops in Pakistan
Published in Abdul Rashid, Munir Zia, Waqar Ahmad, Micronutrient Fertilizer Use in Pakistan, 2023
Abdul Rashid, Munir Zia, Waqar Ahmad
Under HarvestZinc Project, Cakmak et al. (2017) investigated the possibility of using iodine-containing fertilizers for agronomic biofortification of cereal (wheat, rice, and maize) grains with iodine. This study was conducted in Turkey, Pakistan, Brazil, and Thailand, and revealed that soil application of iodine products did not increase iodine in wheat grains. In contrast to the soil application, foliar sprays of KIO3 enhanced grain iodine concentrations up to five- to ten-fold without affecting grain yield. Adding KNO3 and a surfactant to the iodine-containing foliar spray further increased grain iodine concentration. Field experiments conducted in different countries confirmed that foliar application with increasing rates of iodine significantly increased grain iodine concentrations in wheat, brown rice, and maize. This increase was also found in the iodine concentration of the endosperm part of wheat grains and in polished rice. Thus, it was concluded that foliar application of iodine-containing fertilizers is highly effective in increasing grain iodine concentrations in wheat, rice, and maize. Spraying KIO3 up to the rate of 0.05% w/v is suggested as the optimal form and rate to be used in agronomic biofortification with iodine. The substantial increase in grain iodine concentrations could contribute to the prevention of iodine deficiency in human populations with low dietary iodine intake.
The risks and benefits of dietary supplements
Published in Charlotte Fabiansson, Stefan Fabiansson, Food and the Risk Society, 2016
Charlotte Fabiansson, Stefan Fabiansson
A lack of calcium can lead to rickets in children or osteoporosis and osteomalacia in later life (Guyton and Hall 2001; Tuck and Datta 2007; Campbell et al. 1994). Symptoms of copper deficiency include defects in connective tissue, anaemia and possibly specific aspects of central nervous system dysfunction (Harris 1997). Iodine deficiency can cause mental retardation, hypothyroidism, goitre, cretinism and varying degrees of other growth and developmental abnormalities (Wolff 1969). A lack of iron can lead to anaemia with impaired physical work performance (Willis et al. 1988). Early signs of magnesium deficiency include loss of appetite, nausea, vomiting, fatigue and weakness (Rude 2010). Phosphorus is so ubiquitous in various foods that near total starvation is required to produce dietary phosphorus deficiency. There are indications that selenium deficiency seldom causes overt illness. However, it might lead to biochemical changes that predispose to illness associated with other stresses (Institute of Medicine 2000). Because of the ubiquity of zinc and its involvement in so many core areas of metabolism, features of zinc deficiency are frequently quite basic and nonspecific, including growth retardation, alopecia, diarrhoea, delayed sexual maturation and impotence, eye and skin lesions, and impaired appetite (Institute of Medicine 2001).
I, 53]
Published in Alina Kabata-Pendias, Barbara Szteke, Trace Elements in Abiotic and Biotic Environments, 2015
Alina Kabata-Pendias, Barbara Szteke
Content of I in human body is estimated at 10–20 mg; more than 95% of total I is accumulated in the thyroid gland (Emsley 2011). The only known roles of I in metabolism are its incorporation into the thyroid hormones, thyroxine (T4) and triiodothyronine (T3), and into the precursor iodotyrosines. Thyroid hormones, and therefore I, are essential for mammalian life. Both hormones have multiple functions in the energy metabolism of cells, in the growth, as a transmitter of nervous stimuli, and as an important factor in brain development. Iodine deficiency reduces the production of thyroid hormones in humans and animals, leading to morphological and functional changes of the thyroid gland, and reduction of the formation of thyroxin. Elemental iodine, I2, is toxic, and its vapor irritates the eyes and lungs. The maximum allowable concentration of I in air, at work places, is 1 mg/m−3. All iodides are toxic, if taken in excess.
In situ characterization of human fingernails by optical front-face fluorescence for the identification of primary hypothyroidism
Published in Instrumentation Science & Technology, 2023
Mohamed Nakkach, Rihem Nouir, Imen Cherni, Mehdi Somaï, Fatma Daoued, Besma Ben Dhaou, Fatma Boussema, Sami Hamzaoui, Hassen Ghalila
Hypothyroidism is a chronic disease in which the thyroid gland produces insufficient hormone to meet peripheral tissue needs. Primary hypothyroidism (PH) refers to thyroid failure resulting from a disease of the thyroid gland and accounts for more than 99% of all cases.[1] The prevalence of overt hypothyroidism (OH) in the general population varies between 0.3% and 3.7% in the USA and between 0.2% and 5.3% in Europe.[2–6] Differences in iodine status affect the prevalence of hypothyroidism, which occurs more frequently in both populations with relatively high iodine intake and populations with severe iodine deficiency.[7,8] OH occurs when serum thyroid stimulating hormone (TSH) levels are higher than 4.5 mIU/L and thyroxine (T4) levels (free and total T4) are below the population reference range.[9] Most symptoms attributed to hypothyroidism are common in the general population and are nonspecific. The most common symptoms of hypothyroidism in adults are fatigue, lethargy, cold intolerance, constipation, hoarseness, weight gain, and dry skin. Less common symptoms of hypothyroidism include nail changes, anemia, and various neurological, musculoskeletal, and metabolic symptoms.[1,10] Other symptoms in hypothyroidism are onycholysis and slow-growing and thin nails.[11]
Urinary Isoflavones Levels in Relation to Serum Thyroid Hormone Concentrations in Female and Male Adults in the U.S. General Population
Published in International Journal of Environmental Health Research, 2021
Patricia A. Janulewicz, Jeffrey M. Carlson, Amelia K. Wesselink, Lauren A. Wise, Elizabeth E. Hatch, Lariah M. Edwards, Junenette L. Peters
Adverse health effects of genistein and daidzein, such as goitrogenic effects, have been well-documented in vitro (Divi and Doerge 1996; Divi et al. 1997; Dixon and Ferreira 2002). An animal study found synergism between high soybean intake and iodine deficiency on the development of thyroid hyperplasia in rats (Ikeda et al. 2000). A human study of infants who consumed soy formula observed an increased risk of goiter, and the condition reversed following iodine supplementation or a switch to cow’s milk (Doerge and Sheehan 2002). In a crossover study of individuals with subclinical hypothyroidism, soy phytoestrogen supplementation precipitated overt hypothyroidism (Sathyapalan et al. 2011). In an early review of 14 clinical trials, the majority of studies did not show anti-thyroid effects of soy isoflavones (Messina and Redmond 2006). However, a more recent study found a positive association between isoflavone consumption and TSH in post-menopausal women (Tonstad et al. 2016).
Perovskite modifiers with porphyrin/phthalocyanine complexes for efficient photovoltaics
Published in Journal of Coordination Chemistry, 2022
From work mentioned above, we can summarize some solutions to realize device performance optimization by using porphyrin as perovskite material additive. Basically, porphyrin having well-aligned HOMO/LUMO levels with perovskite can boost device performance by enhancing hole/electron extraction and transportation. In terms of defect passivation, electron-deficient groups (such as fullerenes) can interact with electron-rich I- to prevent it from migration, thus inhibiting the generation of defects. Some metal porphyrin complexes can also hinder the production of defects by adsorbing I-/I2, which can also encapsulate polluting I-/I2. In addition, electron-rich groups (such as carboxyl, cyano, ester, carbonyl, thiol, N atoms on porphyrin rings, etc.) can react with under-coordinated Pb2+ to passivate lead defects and prevent Pb from escaping. Research has also used F to from H-bond with the ammonium group in organic cationic to stabilize organic cation or utilize porphyrin molecules at the grain boundary to inhibit the migration of organic cation. The I-/I2 adsorption ability of certain porphyrins is also an advantage to prevent the occurrence of iodine deficiency. Passivation of defects can reduce the non-radiative recombination of photocarriers and improve PCE of perovskite materials. As the thermal decomposition process is more likely to start from defects on the surface or grain boundary [39–44], the passivation of defects can also improve thermal stability of devices. Water-induced degradation of perovskite materials mainly starts from the grain boundary [45], while porphyrins mostly exist at the grain boundary and surface of perovskite materials. The hydrophobicity of porphyrins enables it to prevent water intrusion, thus improving the water stability of PSCs. In terms of optical stability, Tang et al. [34] used rare earth ion Eu3+ to absorb ultraviolet light, specifically aimed at improving the optical stability. In other work, the improvement of optical stability is mostly due to passivation of defects.