Introduction: Iron-mediated cell death (ferroptosis) is a proposed mechanism of Alzheimer's disease (AD) pathology. While iron is essential for basic biological functions, its reactivity generates oxidants which contribute to cell damage and death.
Methods: To further resolve mechanisms of iron-mediated toxicity in AD, we analyzed post mortem human brain and ApoEFAD mice.
Background: Deferoxamine (DFO) and other iron chelators are clinically used for cancer and stroke. They may also be useful for Alzheimers disease (AD) to diminish iron from microbleeds. DFO may also stimulate antioxidant membrane repair which is impaired during AD.
View Article and Find Full Text PDFIron-mediated cell death (ferroptosis) is a proposed mechanism of Alzheimers disease (AD) pathology. While iron is essential for basic biological functions, its reactivity generates oxidants which contribute to cell damage and death. To further resolve mechanisms of iron-mediated toxicity in AD, we analyzed postmortem human brain and ApoEFAD mice.
View Article and Find Full Text PDFBackground And Objectives: Diagnostic uncertainty is challenging to identify and study in clinical practice. This study compares differences in diagnosis code and health care utilization between a unique cohort of hospitalized children with uncertain diagnoses (UD) and matched controls.
Patients And Methods: This case-control study was conducted at Cincinnati Children's Hospital Medical Center.
Understanding the nanoscale chemical speciation of heterogeneous systems in their native environment is critical for several disciplines such as life and environmental sciences, biogeochemistry, and materials science. Synchrotron-based X-ray spectromicroscopy tools are widely used to understand the chemistry and morphology of complex material systems owing to their high penetration depth and sensitivity. The multidimensional (4D+) structure of spectromicroscopy data poses visualization and data-reduction challenges.
View Article and Find Full Text PDFRadioactive acidic liquid waste is a common byproduct of uranium (U) and plutonium (Pu) enrichment and recycling processes whose accidental and planned release has led to a significant input of U into soils and sediments across the world, including at the U.S. DOE's Hanford site (WA, USA).
View Article and Find Full Text PDFParticulate matter (PM) air pollution poses a major global health risk, but the role of iron (Fe) is not clearly defined because chemistry at the particle-cell interface is often not considered. Detailed spectromicroscopy characterizations of PM samples from the San Joaquin Valley, CA identified major Fe-bearing components and estimated their relative proportions. Iron in ambient PM was present in spatially and temporally variable mixtures, mostly as Fe(III) oxides and phyllosilicates, but with significant fractions of metallic iron (Fe(0)), Fe(II,III) oxide, and Fe(III) bonded to organic carbon.
View Article and Find Full Text PDFSteroid 5α-reductase type 2 deficiency (5α-RD2) and androgen insensitivity syndrome (AIS) are difficult to distinguish clinically and biochemically, and adrenal-derived androgens have not been investigated in these conditions using modern methods. The objective of the study was to compare Chinese patients with 5α-RD2, AIS, and healthy men. Sixteen patients with 5α-RD2, 10 patients with AIS, and 39 healthy men were included.
View Article and Find Full Text PDFMineral dissolution and secondary phase precipitation may control the fate of inorganic contaminants introduced to soils and sediments during liquid waste discharges. When the solutions are aggressive enough to induce transformation of native minerals, incorporated contaminants may be released during dissolution due to percolation of meteoric waters. This study evaluated the release of uranium (U) from Hanford sediments that had been previously reacted for 180 or 365 days with liquid waste solutions containing U with and without 3 mM dissolved phosphate at pH 2 and 3.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
January 2022
Context: Testicular adrenal rest tumors (TART) are a common complication in males with classic 21-hydroxylase deficiency (21OHD). TART are likely to contribute to the androgen excess in 21OHD patients, but a direct quantification of steroidogenesis from these tumors has not been yet done.
Objective: We aimed to define the production of 11-oxygenated 19-carbon (11oxC19) steroids by TART.
Bone metastasis is a complication of prostate cancer in up to 90% of men afflicted with advanced disease. Therapies that reduce androgen exposure remain at the forefront of treatment. However, most prostate cancers transition to a state whereby reducing testicular androgen action becomes ineffective.
View Article and Find Full Text PDFIntroduction: Recent studies have shown 11-oxygenated androgens (11oAs) are the dominant androgens in premature adrenarche (PA). Our objective was to compare 11oAs and conventional androgens in a well-defined cohort of children with PA or premature pubarche (PP) and correlate these androgens with metabolic markers.
Methods: A prospective cross-sectional study was conducted at a university hospital.
The speciation, oxidation states, and relative abundance of iron (Fe) phases in PM samples from two locations in urban Los Angeles were investigated using a combination of bulk and spatially resolved, element-specific spectroscopy and microscopy methods. Synchrotron X-ray absorption spectroscopy (XAS) of bulk samples (i.e.
View Article and Find Full Text PDFMethylmercury (MeHg) produced by anaerobic bacteria in lakes and reservoirs, poses a threat to ecosystem and human health due to its ability to bioaccumulate in aquatic food webs. This study used 48-hr microcosm incubations of profundal sediment and bottom water from a sulfate-rich, hypereutrophic reservoir to assess seasonal patterns of MeHg cycling under various treatments. Treatments included addition of air, Hg(II), organic carbon, and microbial inhibitors.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
August 2020
Context: The gonads are the major source of sex steroids during reproductive ages. The gonadal function declines abruptly in women and gradually in men. The adrenals produce 11-oxygenated androgens (11-oxyandrogens), which start rising during adrenarche.
View Article and Find Full Text PDFThe long-term stability of U(IV) solid phases in anaerobic aquifers depends upon their reactivity in the presence of oxidizing chemical species and microbial catalysts. We performed flow-through column experiments under anaerobic conditions to investigate the mechanisms and dissolution rates of biogenic, noncrystalline UO(s) by chemical oxidants (nitrate and/or nitrite) or by , a widespread, denitrifying, chemolithoautotrophic model bacterium. Dissolution rates of UO(s) with dissolved nitrite were approximately 5 to 10 times greater than with nitrate alone.
View Article and Find Full Text PDFChemical forms of phosphorus (P) in airborne particulate matter (PM) are poorly known and do not correlate with solubility or extraction measurements commonly used to infer speciation. We used P X-ray absorption near-edge structure (XANES) and P nuclear magnetic resonance (NMR) spectroscopies to determine P species in PM collected at four mountain sites (Colorado and California). Organic P species dominated samples from high elevations, with organic P estimated at 65-100% of total P in bulk samples by XANES and 79-88% in extracted fractions (62-84% of total P) by NMR regardless of particle size (≥10 or 1-10 μm).
View Article and Find Full Text PDFContext: The human adrenal is the dominant source of androgens in castration-resistant prostate cancer (CRPC) and classic 21-hydroxylase deficiency (21OHD). Abiraterone, derived from the prodrug abiraterone acetate (AA), inhibits the activity of cytochrome P450 17-hydroxylase/17,20-lyase (CYP17A1), the enzyme required for all androgen biosynthesis. AA treatment effectively lowers testosterone and androstenedione in 21OHD and CRPC patients.
View Article and Find Full Text PDFAdrenal vein sampling (AVS) is required to distinguish unilateral from bilateral aldosterone sources in primary aldosteronism (PA), and cortisol is used for AVS data interpretation, but cortisol has several pitfalls. In this study, we present the utility of several other steroids in PA subtyping, both during AVS, as well as in peripheral serum. We included patients with PA who underwent AVS at University of Michigan between 2012 and 2018.
View Article and Find Full Text PDFDue to the potential toxicity of cadmium (Cd) and its presence in various waste products found in the environment, it is necessary to develop methods to attenuate and remediate Cd waste. Sorption of Cd to mineral surfaces is a potential route to accomplish this goal. This work focused on improving our molecular-scale understanding of the chemistry of Cd interactions with gibbsite and kaolinite mineral surfaces.
View Article and Find Full Text PDFEnviron Sci Process Impacts
March 2019
Carbonaceous nanomaterials represent a significant portion of ultra-fine airborne particulate matter, and iron is the most abundant transition metal in air particles. Owing to their high surface area and atmospheric oxidation, carbon nanoparticles (CNP) are enriched with surface carbonyl functional groups and act as a host for metals and small molecules. Using a synthetic model, concentration-dependent changes in the chemical speciation of iron adsorbed on oxidized carbon surfaces were investigated by a combination of X-ray and electron microscopic and spectroscopic methods.
View Article and Find Full Text PDFObjectives: To identify caregiver preferences for discharge education components, content, and techniques.
Methods: Before discharge education, a 9-question structured interview was performed with caregivers of children from 2 populations admitted to the hospital medicine service: patients with asthma (age 2-17 years) or children who were not dependent on technology (age <2 years). McNemar's tests were used to evaluate for significant differences between response options.