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Components of Nutrition
Published in Christopher Cumo, Ancestral Diets and Nutrition, 2020
Left of the zigzag line known as the staircase are metals, notable in electrons’ ability to move through them. To the right are nonmetals, which resist electron flow. For completeness, elements on the staircase have characteristics of metals and nonmetals, do not neatly fit either category, and are known as metalloids. Most mineral elements are metals. The major minerals are sodium, calcium, potassium, phosphorus, and magnesium. Necessary in smaller amounts are the minor minerals: manganese, iron, zinc, iodine, fluorine, selenium, copper, chromium, cobalt, and molybdenum. Of these, only fluorine is a nonmetal. Although many nutritionists and dieticians do not consider chlorine a mineral, it appears to fulfill the criteria. It too is a nonmetal. Being in the column (group) of the Periodic Table known as the halogens, fluorine and chlorine share properties. The body needs chlorine as the electrolyte chloride and to make hydrochloric acid, which aids digestion.
Nutrients in Bamboo Shoots
Published in Nirmala Chongtham, Madho Singh Bisht, Bamboo Shoot, 2020
Nirmala Chongtham, Madho Singh Bisht
Silicon (Si) is a non-metallic element and the second most abundant element in the Earth’s crust with a great affinity for oxygen, forming 92% silica and silicates. It is also the most abundantly available trace element after iron and zinc. Chemically, silica is an oxide of silicon, viz. silicon dioxide and is generally colourless to white and insoluble in water. When associated with metals or minerals the family of silicates is formed. Humans are exposed to numerous sources of silica/silicon including dust, food, pharmaceuticals, cosmetics and medical implants and devices. As a metalloid, silicon has been used in many industrial applications including use as an additive in the food and beverage industry. As a result, humans are exposed to silicon through both environmental exposures and also as a dietary component. Bamboo extract is the richest known source of natural silica, containing over 70% organic silica. This is more than 10 times the level found in the widely used Horsetail plant (Equisetum) that contains 5% to 7% silica.
Risk Characterization
Published in Ted W. Simon, Environmental Risk Assessment, 2019
Hippocrates, Aristotle, and Paracelsus are reported to have used arsenic as a medicine. Nero used arsenic to murder his stepbrother Brittanicus and clear his path to become Emperor of Rome.103 Arsenic has been used as a poison and a medicine dating back to 2000 bce.104 The Emperor Napoleon may have been poisoned with arsenic in his wine. The toxicity of arsenic is common knowledge—this storied metalloid has been the murder weapon of choice in both real life and fiction.104
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
The toxic smoke generated from tobacco has both genotoxic and carcinogenic properties. Tobacco contains both organic and inorganic chemical compounds that could be carcinogenic to humans. Tobacco smoke is very toxic and harmful to human health since tobacco contains 4000 identified chemical compounds (Mussalo-Rauhamaa et al. 1986; El-Agha and Gökmen 2002). Among them are metals and metalloids, such as As, Cd, Cr, Ni, and Pb. Heavy metals are present in the MSS and SSS (Torrence et al. 2002; Stabbert et al. 2003; Chang et al. 2005). According to the literature, 2.0% of Cd, 5.8% of Pb, 2.0% of Cu in raw tobacco are transmitted to MSS (Mussalo-Rauhamaa et al. 1986). When people smoke, between 6 and 11% of Pb in raw tobacco is transferred to MSS; half of that amount is believed to reach the smokers' lungs (Galazyn-Sidorczuk et al. 2008). Furthermore, the levels of heavy metals in smokers' fat, blood, and liver are significantly higher than those of non-smokers (Mussalo-Rauhamaa et al. 1986; El-Agha and Gökmen 2002). Analysis of smoker's blood and urine showed that Cd concentrations were 2–4 times more in smokers than non-smokers (Galazyn-Sidorczuk et al. 2008). Most heavy metals can be either carcinogenic to the human body or have the likelihood to be carcinogenic to the human body (De Sousa Viana et al. 2011).
Promising treatment strategies to combat Staphylococcus aureus biofilm infections: an updated review
Published in Biofouling, 2020
P. S. Seethalakshmi, Riya Rajeev, George Seghal Kiran, Joseph Selvin
Metalloids are elements which exhibit mixed properties of metals as well as non-metals (Yazdi et al. 2016). Metalloid nanoparticles have been used for various biomedical applications such as cancer therapy and in vivo imaging (Byrappa et al. 2008; Rabin et al. 2006). There are several reports of metalloid nanoparticles like silicon and selenium nanoparticles being used for biofilm inhibition of pathogenic bacteria. Shakibaie et al. (2015) reported that biologically synthesized selenium nanoparticles using Bacillus sp. MSh-1, inhibited biofilm formation by S. aureus at very low concentrations. Sonkusre and Cameotra (2015) biologically synthesized selenium nanoparticles using Bacillus licheniformis strain JS2 and reported that the adherence of S. aureus in catheters coated with nanoparticles was significantly reduced after 72 h. Selenium nanoparticles coated on polycarbonate films reduced biofilms by 27%, suggesting that manufacturing medical devices using polycarbonate incorporated with nanoparticles can prevent bacterial adherence (Wang and Webster 2012).
Prenatal arsenic exposure interferes in postnatal immunocompetence despite an absence of ongoing arsenic exposure
Published in Journal of Immunotoxicology, 2020
Mainak Chakraborty, Moumita Bhaumik
The World Health Organization (WHO) has indicated that a “safe” level of As in drinking water is 10 µg/L or 0.01 ppm for adults. In the experiments here, much higher levels of arsenic trioxide (As2O3) in drinking water were employed so as to mimic a scenario of highly exposed local populations in Bangladesh. Studies using animal models of As exposure have utilized different approaches to assess immunotoxicities induced by the metalloid. A prevailing approach to assess alterations in the immune repertoire caused by As exposure was to examine changes in disease susceptibility; Farzan et al. (2013) found that As exposures of young rats resulted in increased susceptibility to pathogen-based respiratory diseases. A study of preschool children in rural Bangladesh showed that repeated As exposures (in water) led to altered BCG vaccination efficacy, i.e. BCG-specific CD4+ T-cells that failed to respond to PPD, the antigen that had been seen earlier by the hosts (Ahmed et al. 2014). Based on these above findings, it is reasonable to conclude that As causes immunosuppression in exposed children.