The explosion and collapse of the World Trade Center (WTC) was a catastrophic event that produced an aerosol plume impacting many workers, residents, and commuters during the first few days after 11 September 2001. Three bulk samples of the total settled dust and smoke were collected at weather-protected locations east of the WTC on 16 and 17 September 2001; these samples are representative of the generated material that settled immediately after the explosion and fire and the concurrent collapse of the two structures. We analyzed each sample, not differentiated by particle size, for inorganic and organic composition. In the inorganic analyses, we identified metals, radionuclides, ionic species, asbestos, and inorganic species. In the organic analyses, we identified polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, polychlorinated dibenzodioxins, polychlorinated dibenzofurans, pesticides, phthalate esters, brominated diphenyl ethers, and other hydrocarbons. Each sample had a basic pH. Asbestos levels ranged from 0.8% to 3.0% of the mass, the PAHs were > 0.1% of the mass, and lead ranged from 101 to 625 microg/g. The content and distribution of material was indicative of a complex mixture of building debris and combustion products in the resulting plume. These three samples were composed primarily of construction materials, soot, paint (leaded and unleaded), and glass fibers (mineral wool and fiberglass). Levels of hydrocarbons indicated unburned or partially burned jet fuel, plastic, cellulose, and other materials that were ignited by the fire. In morphologic analyses we found that a majority of the mass was fibrous and composed of many types of fibers (e.g., mineral wool, fiberglass, asbestos, wood, paper, and cotton). The particles were separated into size classifications by gravimetric and aerodynamic methods. Material < 2.5 microm in aerodynamic diameter was 0.88-1.98% of the total mass. The largest mass concentrations were > 53 microm in diameter. The results obtained from these samples can be used to understand the contact and types of exposures to this unprecedented complex mixture experienced by the surviving residents, commuters, and rescue workers directly affected by the plume from 11 to 12 September and the evaluations of any acute or long-term health effects from resuspendable dust and smoke to the residents, commuters, and local workers, as well as from the materials released after 11 September until the fires were extinguished. Further, these results support the need to have the interior of residences, buildings, and their respective HVAC systems professionally cleaned to reduce long-term residential risks before rehabitation.
Tea is rich in polyphenols and has a variety of biological activities. In order to better understand the biological effects of tea constituents on human health, markers for their exposure and their metabolic fates are needed. Previously, we have characterized several catechin metabolites in the blood and urine, but more information on the metabolite profile of tea polyphenols is needed. In the present study, the human urinary metabolite profile of tea polyphenols was investigated using liquid chromatography/electrospray ionization tandem mass spectrometry with data-dependent acquisition. With data-dependent MS/MS analysis by collecting the MS2 and MS3 spectra of the most intense ions in the sample, we identified more than twenty metabolites of tea polyphenols from human urine samples. (-)-Epigallocatechin (EGC) glucuronide, methylated EGC glucuronide, methylated EGC sulfate, (-)-epicatechin (EC) glucruronide, EC sulfate, methylated EC sulfate, as well as the glucuronide and sulfate metabolites of the ring-fission metabolites of tea catechins, 5-(3',4',5'-trihydroxyphenyl)-gamma-valerolactone (M4), 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone (M6) and 5-(3',5'-dihydroxyphenyl)-gamma-valerolactone (M6'), were the major human urinary metabolites of tea polyphenols. To our knowledge, this is the first report of the direct simultaneous analysis of the human urinary metabolite profile of tea polyphenols using single sample analysis. This method can also be used for thorough investigations of the metabolite profiles of many other dietary constituents.
Abstract(−)-Epigallocatechin-3-gallate (EGCG), the most abundant and biologically active compound in tea, has been proposed to have beneficial health effects, including prevention of cancer and heart disease. Different mechanisms of action of EGCG have been proposed, based mainly on studies in cell line systems, in which EGCG is not stable. It has been proposed that oxidation of EGCG and its production of reactive oxygen species are responsible for the biological activities such as receptor inactivation and telomerase inhibition. It is unclear, however, if this phenomenon occurs in vivo. In the present study, the stability of EGCG and product formation in Tris-HCl buffer was investigated using realtime mass spectrometry combined with tandem mass ion mapping. With real-time mass data acquisition, we demonstrate for the first time the formation of EGCG quinone, EGCG dimer quinone, and other related compounds. The structural information of the major appearing ions was provided by tandem mass analysis of each ion. A mechanism for the autoxidation of EGCG was proposed based on the structural information of these ions. None of these oxidation products were observed in the plasma samples of mice after treatment with 50 mg/kg EGCG, i.p. daily for 3 days. Instead, the methylated and conjugated metabolites of EGCG were observed. Therefore the roles of EGCG autoxidation in the biological activities of this compound in vivo remain to be investigated further.
Numerous preclinical, epidemiologic, and clinical studies have suggested the benefits of vitamin D and its analogues for the prevention and treatment of cancer. However, the hypercalcemic effects have limited the use of 1α,25(OH) 2 D 3 , the hormonally active form of vitamin D. To identify vitamin D analogues with better efficacy and low toxicity, we have tested >60 novel Gemini vitamin D analogues with a unique structure of two side chains for growth inhibition of breast cancer cells. Our initial studies found that some Gemini analogues are 5-15 times more active than 1α,25(OH) 2 D 3 in growth inhibition assay. In vivo experiments were designed to study the inhibitory effect of selected Gemini vitamin D analogues against mammary carcinogenesis by using -hexafluoro-19-nor-cholecalciferol] administration inhibited by 60% the NMUinduced mammary tumor burden compared with the NMU-treated control group, but these compounds were devoid of hypercalcemia toxicity. In an ER-negative xenograft model, Gemini 0097 significantly suppressed tumor growth without hypercalcemia toxicity. We found that the inhibitory effect of Gemini 0097 was associated with an increased level of cyclin-dependent kinase inhibitor p21 and the insulin-like growth factor binding protein 3 in both ER-positive and ER-negative mammary tumors. Our results suggest that Gemini vitamin D analogues may be potent agents for the prevention and treatment of both ER-positive and ER-negative breast cancer without hypercalcemia toxicity.In the United States, breast cancer remains the most frequently diagnosed cancer and the second leading cause of cancer death in women according to Cancer Statistics from the American Cancer Society. Because of the complexity and heterogeneity of mammary carcinogenesis (1), many pharmacologic agents have been studied for their effects on the prevention of breast cancer. For example, selective estrogen receptor (ER) modulators such as tamoxifen and raloxifene have achieved significant reduction of breast cancer incidence in women at high risk (2, 3). However, selective ER modulators are not effective in preventing ER-negative breast cancer, which corresponds to at least one third of the breast cancer cases (4). The vitamin D receptor (VDR), a member of the nuclear receptor superfamily, has been suggested as a target for both ER-positive and ER-negative breast cancer prevention (5, 6) because it is present in most breast tumors (4), and VDR ablation in mice was reported to enhance carcinogeninduced formation of mammary tumors (7). These results suggest a role of vitamin D signaling in the regulation of mammary tumorigenesis.The ligand for VDR, 1α,25-dihydroxyvitamin D 3 (1α,25(OH) 2 D 3 ; the key hormone in calcium/phosphate homeostasis) is a hormonally active metabolite synthesized from vitamin D 3 predominantly through hydroxylation by a 25-hydroxylase in the
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