A5083444360- Vitamin D Research Studies
- Vitamin C and Antioxidants Research
- Hormonal and reproductive studies
- Opioid Use Disorder Treatment
- Biotin and Related Studies
- Effects and risks of endocrine disrupting chemicals
- Forensic Toxicology and Drug Analysis
- Metabolomics and Mass Spectrometry Studies
- Microfluidic and Capillary Electrophoresis Applications
- Diet and metabolism studies
- Pharmacogenetics and Drug Metabolism
- Berberine and alkaloids research
- Mass Spectrometry Techniques and Applications
- Parathyroid Disorders and Treatments
- Synthesis and Biological Evaluation
- Cannabis and Cannabinoid Research
- Nicotinic Acetylcholine Receptors Study
- Blood groups and transfusion
- Biosimilars and Bioanalytical Methods
- Alkaloids: synthesis and pharmacology
- Smoking Behavior and Cessation
- Kidney Stones and Urolithiasis Treatments
- Curcumin's Biomedical Applications
- Hyperglycemia and glycemic control in critically ill and hospitalized patients
- Retinopathy of Prematurity Studies
Khon Kaen University
2007-2025
University of Washington
2012-2024
National Kidney Foundation
2016
University of Washington Medical Center
2005-2007
Harborview Medical Center
2005-2007
Abstract BACKGROUND Vitamin D deficiency is associated with poor bone health and other adverse outcomes; however, the associations are greatly attenuated in black vs white individuals. One possible explanation for this attenuation different concentrations of bioavailable vitamin metabolites plasma, which estimated equations that include total concentration binding globulin (VDBG) haplotype-specific dissociation constants. METHODS We developed a method to quantify VDBG LC-MS/MS could also...
1α,25-dihydroxy vitamin D [1,25(OH)(2)D] is the active metabolite of D. Antibody-based detection methods lack specificity, but when combined with isotope dilution/ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry, immunoextraction provides an attractive method for 1,25(OH)(2)D. We developed a simultaneous quantification 1,25(OH)(2)D(2) and 1,25(OH)(2)D(3) 4.6-min instrument cycle time. Results are available 36 h after sample preparation begins.Sample consisted protein...
Renal function generally is assessed by measurement of GFR and urinary albumin excretion. Other intrinsic kidney functions, such as proximal tubular secretion, typically are not quantified. Tubular secretion solutes more efficient than glomerular filtration a major mechanism for renal drug elimination, suggesting important clinical consequences dysfunction. Measuring an independent marker may provide insight into disease etiology improve prediction adverse outcomes. We estimated measuring...
Serum levels of 25-hydroxyvitamin D are important in establishing true vitamin humans. The purposes this study were to develop a sensitive, specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detection D(2) and D(3) establish reference intervals these analytes. Chromatographic separation 25(OH)D(2) 25(OH)D(3) was achieved after adding deuterated Delta(9)-tetrahydrocannabinol (D(9)-THC-D(3)) organic extraction. 3 ions ionized using positive electrospray ionization...
A 58-year-old woman with debilitating ankylosing spondylitis who was born to consanguineous parents found have an apparent severe vitamin D deficiency that did not respond supplementation. Liquid chromatography-tandem mass spectrometry showed the absence of circulating D-binding protein, and chromosomal microarray confirmed a homozygous deletion group-specific component (GC) gene encodes protein. Congenital protein resulted in normocalcemia relatively mild disruption bone metabolism, this...
Immunoassays for 1α,25-dihydroxyvitamin D [1α,25(OH)(2)D] lack analytical specificity. We characterized the cross-reactivity of an anti-1α,25(OH)(2)D antibody with purified vitamin metabolites and used these data to map chemical features 1α,25(OH)(2)D that are important binding. Additionally, we hypothesized when combined isotope-dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS), could be semiselectively enrich structurally similar in a multiplexed assay.Sample preparation...
The human liver fluke, Opisthorchis viverrini, is a significant risk factor for cholangiocarcinoma (CCA) in Thailand. Praziquantel (PZQ) the primary treatment opisthorchiasis but associated with adverse effects and potential development of CCA amid chronic infection reinfection, prompting search alternative treatments. Thunbergia laurifolia widely used detoxification from lead poisoning other toxins. bioactive compounds T. are categorized into sterols, phenolics, carotenoids, glycosides,...
Despite its clear advantages over immunoassay-based testing, the measurement of serum thyroglobulin by mass spectrometry remains limited to a handful institutions. Slow adoption clinical laboratories could reflect accessibility existing methods that have sensitivity comparable modern immunoassays, as well lack tools for calibration and assay harmonization.
Abstract Background: High-performance liquid chromatography–tandem mass spectrometric (LC-MS/MS)1 analysis of plasma free metanephrines is the most diagnostically sensitive and specific screening test for diagnosis pheochromocytoma. We sought to develop an in-house method this expensive Methods: used off-line isopropanol protein precipitation remove interfering substances before LC-MS/MS analysis. compared extraction efficiency limits quantification those previously reported solid-phase...
When chronic pain patients are suspected of being non-compliant, their therapy can be withdrawn. Therefore, sensitive and specific confirmatory testing is important for identifying diversion adherence. This work aimed to develop a novel liquid chromatography tandem mass spectrometry (LC–MS-MS) method detect 14 opioids six opioid glucuronide metabolites in urine with minimal sample preparation. Analytes included were morphine, oxymorphone, hydromorphone, oxycodone, hydrocodone, codeine,...
Proteomic analysis of blood proteins in dried spots (DBS) is gaining attention as a possible replacement for measurements plasma/serum collected by venipuncture. We aimed to develop and provisionally validate nanoflow LC-PRM-MS method clinical use.We used Skyline quantify glycated hemoglobin-β, apolipoprotein A-I, B DBS. Precision, linearity, interferences, stability were determined the was analyze samples from 36 human volunteers. The compared with clinically validated paired via...
The sensitive and specific detection of nicotine, its metabolites, the tobacco alkaloid anabasine is useful in evaluating success smoking cessation treatments detecting use, passive exposure, nontobacco nicotine exposure potential transplant recipients, insurance clients, elective surgical patients. Rapid sample preparation extended high-performance liquid chromatographic separation alkaloids metabolites was interfaced with tandem mass spectrometry. By using deuterated internal standards...
Quantifying the variability of biomarkers is important, as high within-person can lead to misclassification individuals. Short-term important markers vitamin D metabolism relatively unknown.A repeatability study was conducted in 160 Atherosclerosis Risk Communities participants (60% female, 28% black, mean age 76 years). Fasting serum drawn at 2 time points, a median 6 (range 3-13) weeks apart. Vitamin binding protein (VDBP) and 25-hydroxyvitamin [25(OH)D] were measured by LC-MS, fibroblast...
Six laboratories associated with the Vitamin D Standardization Program (VDSP) participated in an interlaboratory comparison of LC tandem MS (MS/MS) methods for determination 24,25-dihydroxyvitamin D3 [24,25(OH)2D3] human serum. The analyzed two different serum-based Standard Reference Materials (SRMs) intended use 25-hydroxyvitamin and 30 samples from External Quality Assessment Scheme (DEQAS). All laboratory 24,25(OH)2D3 were based on isotope dilution LC-MS/MS; three used derivatization...
C-peptide is used as a marker of endogenous insulin secretion in the assessment residual β-cell function diabetes and diagnostic workup hypoglycemia. Previously developed LC-MS/MS methods to quantify serum concentrations have monitored intact peptide, which ionizes poorly. As result, leveraged immunoaffinity enrichment or two-dimensional chromatography. In this study, we aimed use proteolysis during sample preparation enhance sensitivity traditional LC-MS/MS.Due absence arginine lysine...
Serum levels of 25-hydroxyvitamin D are important in establishing true vitamin humans. The purposes this study were to develop a sensitive, specific liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for detection 25- hydroxyvitamin D2 and D3 establish reference intervals these analytes. Chromatographic separation 25(OH)D2 25(OH)D3 was achieved after adding deuterated ▵9-tetrahydrocannabinol (▵9-THC-D3) organic extraction. 3 ions ionized using positive electrospray ionization...
In this study we determined how zinc heparin affected ionized calcium concentration determinations. Zinc produced a positive bias (0.020–0.067 mmol 1−1) in measurement serum/whole blood and negative (−0.035 to −0.110 with aqueous standards. To test if the was due ions displacing from its proteincalcium complexes, reproduced effect by adding ZnCl2 pooled serum. Changes [ZnCl2] (0.1–0.5 caused dose-dependent increase, constant ([ZnCl2], 0.5–1.25 or decrease ([ZnCl2] > 1.25 concentration,...