Classification Term: 4152
Homogeneous alkaline earth metal compounds (ontology term: CHEMONTID:0000428)
Inorganic compounds containing only metal atoms,with the largest atom being a alkaline earth metal atom." []
found 6 associated metabolites at class metabolite taxonomy ontology rank level.
Ancestor: Homogeneous metal compounds
Child Taxonomies: There is no child term of current ontology term.
Strontium
Strontium is a chemical element with the symbol Sr and the atomic number 38. The first large scale application of strontium was in the production of sugar from sugar beet. The human body absorbs strontium as if it were calcium. [Wikipedia]. Strontium is found in many foods, some of which are cucumber, parsnip, allspice, and apple. Strontium presents a health problem since it substitutes for calcium in bone, preventing expulsion from the body. Physiologically, it exists as an ion in the body.
Beryllium
Beryllium is a light-weight metallic element, which was first recognized as a lung hazard in Europe in the 1930s, shortly after its first production in modern industry. People exposed to beryllium compounds are at increased risk of developing beryllium sensitization and chronic beryllium disease (CBD). The chronic lung disease was first described among workers exposed to beryllium-containing materials used in the manufacture of fluorescent lamps. In primary production of beryllium metal, which was used in nuclear weapons components, physicians recognized severe dermatitis, reversible pneumonitis, and chronic granulomatous lung disease. Physiologically, this metal/element exists as an ion in the body. It is now recognized that the physicochemical properties of beryllium compounds may account for the differing clinical presentations in different industries. In primary production of beryllium metal, soluble salts are present and cause rashes in approximately one fourth of exposed workers and reversible acute pneumonitis in a smaller portion of the workforce. After heavy inhalation exposures, radiographic abnormalities evolve at approximately three weeks; resolution of symptoms and radiologic abnormalities away from exposure occur only after months, but symptoms recur immediately upon reexposure. The granulomatous nature of chronic beryllium disease is now known to be caused by cell-mediated sensitization to beryllium. Chronic beryllium disease (CBD) is a granulomatous lung disorder characterized by the accumulation of beryllium-specific CD4(+) T cells. Depending on genetic susceptibility and the nature of the exposure, CBD occurs in up to 20\\% of exposed workers. Genetic susceptibility has been associated with particular HLA-DP alleles, especially those possessing a negatively charged glutamic acid residue at the 69th position of the beta-chain. The mechanism for this association lies in the ability of these HLA-DP molecules to bind and present beryllium to pathogenic CD4(+) T cells. Large numbers of effector memory, beryllium-specific CD4(+) T cells are recruited to the lung of these subjects and secrete Th1-type cytokines upon beryllium recognition. The presence of circulating beryllium-specific CD4(+) T cells directly correlates with the severity of lymphocytic alveolitis. Since 1987, this biomarker of sensitization has enabled medical surveillance of beryllium-exposed workforces. Beryllium lymphocyte proliferation tests have been used to screen workers to detect sensitization, to characterize epidemiologically workplace risks for beryllium sensitization, and to evaluate the effectiveness of interventions intended to prevent sensitization. The most compelling real-world example of genetic testing for susceptibility to a workplace exposure involves those industries that process or fabricate beryllium. Under reasonable assumptions, the longitudinal positive predictive value of the HLA-DPB1-Glu69 marker of susceptibility to beryllium disease is 12\\%. Interpretive challenges further limit the utility of the test and may inadvertently suggest a false sense of safety among workers. Reduction in inhalation exposure to beryllium has not resulted in a concomitant reduction in the occurrence of beryllium sensitization or CBD, suggesting that continued prevalence may be due, in part, to unchecked skin exposure to beryllium-containing particles. (PMID: 17094767, 16697706, 16231190) [HMDB]. Beryllium is found in spinach. Beryllium is a light-weight metallic element, which was first recognized as a lung hazard in Europe in the 1930s, shortly after its first production in modern industry. People exposed to beryllium compounds are at increased risk of developing beryllium sensitization and chronic beryllium disease (CBD). The chronic lung disease was first described among workers exposed to beryllium-containing materials used in the manufacture of fluorescent lamps. In primary production of beryllium metal, which was used in nuclear weapons components, physicians recognized severe dermatitis, reversible pneumonitis, and chronic granulomatous lung disease. Physiologically, this metal/element exists as an ion in the body. It is now recognized that the physicochemical properties of beryllium compounds may account for the differing clinical presentations in different industries. In primary production of beryllium metal, soluble salts are present and cause rashes in approximately one fourth of exposed workers and reversible acute pneumonitis in a smaller portion of the workforce. After heavy inhalation exposures, radiographic abnormalities evolve at approximately three weeks; resolution of symptoms and radiologic abnormalities away from exposure occur only after months, but symptoms recur immediately upon reexposure. The granulomatous nature of chronic beryllium disease is now known to be caused by cell-mediated sensitization to beryllium. Chronic beryllium disease (CBD) is a granulomatous lung disorder characterized by the accumulation of beryllium-specific CD4(+) T cells. Depending on genetic susceptibility and the nature of the exposure, CBD occurs in up to 20\\% of exposed workers. Genetic susceptibility has been associated with particular HLA-DP alleles, especially those possessing a negatively charged glutamic acid residue at the 69th position of the beta-chain. The mechanism for this association lies in the ability of these HLA-DP molecules to bind and present beryllium to pathogenic CD4(+) T cells. Large numbers of effector memory, beryllium-specific CD4(+) T cells are recruited to the lung of these subjects and secrete Th1-type cytokines upon beryllium recognition. The presence of circulating beryllium-specific CD4(+) T cells directly correlates with the severity of lymphocytic alveolitis. Since 1987, this biomarker of sensitization has enabled medical surveillance of beryllium-exposed workforces. Beryllium lymphocyte proliferation tests have been used to screen workers to detect sensitization, to characterize epidemiologically workplace risks for beryllium sensitization, and to evaluate the effectiveness of interventions intended to prevent sensitization. The most compelling real-world example of genetic testing for susceptibility to a workplace exposure involves those industries that process or fabricate beryllium. Under reasonable assumptions, the longitudinal positive predictive value of the HLA-DPB1-Glu69 marker of susceptibility to beryllium disease is 12\\%. Interpretive challenges further limit the utility of the test and may inadvertently suggest a false sense of safety among workers. Reduction in inhalation exposure to beryllium has not resulted in a concomitant reduction in the occurrence of beryllium sensitization or CBD, suggesting that continued prevalence may be due, in part, to unchecked skin exposure to beryllium-containing particles. (PMID: 17094767, 16697706, 16231190).
Barium
Ba (137.905236)
Barium is a dense alkaline earth metal that occurs in nature as a divalent cation in combination with other elements. Physiologically, it exists as an ion in the body. In addition to its natural presence in the Earths crust, and therefore its natural occurrence in most surface waters, barium is also released to the environment via industrial emissions. The residence time of barium in the atmosphere may be up to several days. Barium sulfate exists as a white orthorhombic powder or crystals. Barite, the mineral from which barium sulfate is produced, is a moderately soft crystalline white opaque to transparent mineral. The most important impurities are iron(III) oxide, aluminium oxide, silica, and strontium sulfate.Barium sulfate has a low toxicity and relatively high density of about 4.5 g·cm-3 (and thus opacity to X-rays). For this reason it is used as a radiocontrast agent in X-ray imaging of the digestive system ("barium meals" and "barium enemas"). Lithopone, a pigment that contains barium sulfate and zinc sulfide, is a permanent white that has good covering power, and does not darken when exposed to sulfides. (Wikipedia). Barium hydroxide is strongly alkaline and therefore corrosive. Barium nitrate caused mild skin irritation and severe eye irritation in rabbits. The lack of reports of skin or eye irritation in humans, despite its widespread use, suggests that barium sulfate, often used as a contrast medium, is not a strong irritant. Useful information on the sensitization potential of barium compounds was not identified. Oral intake from drinking water and food is the most prevalent route of exposure to barium compounds for the general population. For the occupational environment, data from industry in the United Kingdom and predictions made using the Estimation and Assessment of Substance Exposure (EASE) model suggest that exposures can be controlled to less than 10 mg/m3 8 hours time weighted average (total inhalable dust). In some situations, control will be to levels significantly below this value. Short term exposures may be higher than 10 mg/m3 for some tasks.The critical end points in humans for toxicity resulting from exposure to barium and barium compounds appear to be hypertension and renal function. Using a no observed adverse effect level (NOAEL) in humans of 0.21 mg barium/kg body weight per day, a tolerable intake value of 0.02 mg/kg body weight per day for barium and barium compounds has been developed in this document.Dissolved barium in aquatic environments may represent a risk to aquatic organisms such as daphnids, but it is apparently of lesser risk to fish and aquatic plants, although data are limited. No adverse effects have been reported in ecological assessments of terrestrial plants or wildlife, although some plants are known to bioaccumulate barium from the soil.(Concise international chemical assessment document 33; http://www.inchem.org/documents/cicads/cicads/cicad33.htm). Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Barium is never found in nature in its pure form due to its reactivity with air. The most common naturally occurring minerals are the very insoluble barium sulfate, BaSO4 (barite), and barium carbonate, BaCO3 (witherite).
CE(18:1(11Z))
CE(18:1(11Z)) is a cholesterol fatty acid ester or simply a cholesterol ester (CE). Cholesterol esters are cholesterol molecules with long-chain fatty acids linked to the hydroxyl group. They are much less polar than free cholesterol and appear to be the preferred form for transport in plasma and for storage. Cholesterol esters do not contribute to membranes but are packed into intracellular lipid particles or lipoprotein particles. Because of the mechanism of synthesis, plasma cholesterol esters tend to contain relatively high proportions of C18 fatty acids. Cholesterol esters are major constituents of the adrenal glands and they also accumulate in the fatty lesions of atherosclerotic plaques. Cholesterol esters are also major constituents of the lipoprotein particles carried in blood (HDL, LDL, VLDL). The cholesterol esters in high-density lipoproteins (HDL) are synthesized largely by transfer of fatty acids to cholesterol from position sn-2 (or C-2) of phosphatidylcholine catalyzed by the enzyme lecithin cholesterol acyl transferase (LCAT). The enzyme also promotes the transfer of cholesterol from cells to HDL. As cholesterol esters accumulate in the lipoprotein core, cholesterol is removed from its surface thus promoting the flow of cholesterol from cell membranes into HDL. This in turn leads to morphological changes in HDL, which grow and become spherical. Subsequently, cholesterol esters are transferred to the other lipoprotein fractions LDL and VLDL, a reaction catalyzed by cholesteryl ester transfer protein. Another enzyme, acyl-CoA:cholesterol acyltransferase (ACAT) synthesizes cholesterol esters from CoA esters of fatty acids and cholesterol. Cholesterol ester hydrolases liberate cholesterol and free fatty acids when required for membrane and lipoprotein formation, and they also provide cholesterol for hormone synthesis in adrenal cells.