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Medical and Biological Applications of Low Energy Accelerators
Published in Vlado Valković, Low Energy Particle Accelerator-Based Technologies and Their Applications, 2022
Trace element concentrations in body fluids and tissues hold much promise as a clinical test. Nuclear analytical methods offer a very interesting approach to these problems because of their ability to detect simultaneously several trace elements in very small samples (biopsy, hair, blood, etc.).
Nutrition and Immunity
Published in Thomas F. Kresina, Immune Modulating Agents, 2020
Srinivas Denduluri, Ranjit Kumar Chandra
Progressive reduction in body stores of many trace elements as a result of decreasing intake leads to immunological changes that in turn increase the risk of infection (Figure 2). There is extensive literature on trace elements and immune functions [1–3] and it is briefly discussed here. Observations in laboratory animals deprived of one dietary element and findings in the rare patient with a single nutrient deficiency have confirmed the crucial role of several vitamins and trace elements in immunocompetence. Several general concepts have been advanced [4]: (1) alterations in immune responses occur early in the course of reduction in micronutrient intake; (2) the extent of immunological impairment depends upon the type of nutrient involved, its interactions with other essential nutrients, severity of deficiency, presence of concomitant infection, and age of the subject; (3) immunological abnormalities predict outcome, particularly the risk of infection and mortality; (4) in the case of many micronutrients, excessive intake is associated with impaired immune responses (discussed separately); (5) tests of immunocompetence are useful in titration of physiological needs and in assessment of safe lower and upper limits of intake of micronutrients. Table 1 identifies some of the specific effects of single-nutrient deficiencies on cellular components of the immune system [5].
Introduction
Published in Nate F. Cardarelli, Tin as a Vital Nutrient:, 2019
At this time 27 of the naturally occurring elements are known to be essential for animal and/or plant life. Seventeen are classified as trace elements: arsenic, boron, chromium, cobalt, copper, fluorine, iodine, iron, manganese, magnesium, molybdenum, nickel, selenium, silicon, tin, vanadium, and zinc. The essentiality of the materials has been described in several authoritative texts.7–9 The vital need for iron in mammalian systems was recognized in the 17th century, iodine by 1850, copper in 1928, manganese in 1931, zinc in 1934, cobalt in 1935, and molybdenum in 1953. The work of Schwarz and colleagues demonstrated the essentiality of selenium in 1957, chromium in 1959, tin in 1970, vanadium in 1971, fluorine in 1972, and silicon in 1972.10 In 1973 nickel was determined by others to be a vital trace nutrient.10 At least some of the functions of most of the trace nutrients are fairly well known, vanadium and tin being exceptions. In general, these trace metals are key components of essential enzyme systems or of vital proteins.11
Relationship between Serum Levels of Selenium and Thyroid Cancer: A Systematic Review and Meta-Analysis
Published in Nutrition and Cancer, 2022
Runhua Hao, Ping Yu, Lanlan Gui, Niannian Wang, Da Pan, Shaokang Wang
For many physiological processes, trace elements are essential micronutrients that are involved in multiple pathological changes in tissues [6]. More than 20 chemical elements are known to influence the normal physiology of the thyroid gland. One element, selenium (Se), is critical for thyroid hormone synthesis and function [7–9]. Normal thyroid function depends on the presence of many trace elements for both the synthesis and metabolism of thyroid hormones [10]. Se is important for thyroid hormone metabolism [11] due to the Se-dependence of the three iodothyronine deiodinases that catalyze thyroid hormone action [12–14]. Even under conditions of severe Se deficiency, tissues with the highest Se content per tissue unit in the thyroid still retain Se and express selenoproteins, highlighting the uniqueness of the human thyroid gland and the importance of Se to thyroid [15–20]. Se is incorporated into selenoproteins, which are vital for removing tissue-damaging peroxides, reducing oxidized proteins and membranes, regulating intracellular reduction-oxidation signaling, in addition to thyroid hormone metabolism [21].
Formulation and rheological evaluation of liposomes-loaded carbopol hydrogels based on thermal waters
Published in Drug Development and Industrial Pharmacy, 2022
Romaissaa Mokdad, Ali Aouabed, Vincent Ball, Feriel Fatima Si Youcef, Noureddine Nasrallah, Béatrice Heurtault, Abdelkader HadjSadok
The physical and chemical composition of BTW and STW is presented in Table 1. BTW and STW are defined as ‘hyper-mineral sulfate-sodium water’ and ‘hyper-mineral chloride-sodium water,’ respectively. Measured pH values were neutral and water temperatures in the springs of Baraka and Salhine were 42 and 45 °C, respectively. The conductivity of STW was 3 times higher than that of BTW. Calcium and magnesium results were found at their highest levels in BTW, whereas in STW contained the highest level of potassium. Sodium concentration in STW was 6 times higher compared to BTW. Similarly, chloride and bicarbonate concentrations were respectively 8 and 3 times higher in STW compared to those measured in BTW. In addition to major elements, BTW and STW showed different concentrations in trace elements. The predominant trace element was iron, followed by selenium and manganese in STW, and zinc and selenium in BTW. Interestingly, both thermal waters are silicate-rich. Related to their osmolality values, BTW and STW can be classified respectively as hypotonic and isotonic waters (Table 1). Several in vivo and clinical investigations have reported that mineral components such as magnesium [48], sulfate [5], manganese [49], selenium [50], calcium, and bicarbonates [51], present in BTW and STW, exerted beneficial effects on skin diseases.
Analyzing pesticides and metal(loid)s in imported tobacco to Saudi Arabia and risk assessment of inhalation exposure to certain metals
Published in Inhalation Toxicology, 2022
Mohammed A. Al Mutairi, Hatim A. Al Herbish, Rakan S. Al-Ajmi, Hatim Z. Alhazmi, Reham A. Al-Dhelaan, Abdullah M. Alowaifeer
Tobacco plants can absorb and hold trace elements obtained from the soil (Kazi et al. 2009). These trace elements can be harmful to human health, even if ingested or inhaled at low concentrations (Behera et al. 2014). In addition, tobacco production involves using many chemicals, such as pesticides (Lecours et al. 2012). Pesticides are widely used before and after harvesting tobacco to protect against pests (Chapman 2003; Rahman et al. 2012). However, the excessive usage of pesticides leads to pesticide residues in a tobacco product that can make their way to the consumer (Khan et al. 2010). To ensure consumers' safety from pesticide exposure, government organizations established maximum residues levels (MRLs) for many pesticides. Both international organizations and different countries' legislation have set MRLs for pesticides in tobacco. However, the agricultural regulation for tobacco is generally poor due to the lack of MRLs, unlike food commodities (Quadroni and Bettinetti 2019). The Cooperation center for Scientific Research Relative to Tobacco (CORESTA) has created guidance for pesticide residue levels (GRLs) for 120 pesticides and their metabolites (ACAC 2020). The generated list is intended for tobacco farmers and people who work in tobacco manufacturing (Bernardi et al. 2016). The CORESTA 2020 list contains GRL values for pesticides from different classes, such as organochlorine, organophosphorus, and pyrethroids. However, the GRLs does not replace the MRLs since they are used only as a reference for tobacco growers.