scholarly journals Estrone Is a Strong Predictor of Circulating Estradiol in Women Age 70 Years and Older

2020 ◽  
Vol 105 (9) ◽  
pp. e3348-e3354
Author(s):  
Susan R Davis ◽  
Alejandra Martinez-Garcia ◽  
Penelope J Robinson ◽  
David J Handelsman ◽  
Reena Desai ◽  
...  
Keyword(s):  
Health Outcomes ◽  
Postmenopausal Women ◽  
Limit Of Detection ◽  
Strong Predictor ◽  
Serum Concentrations ◽  
Community Based ◽  
Cross Sectional ◽  
A Value ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

Abstract Importance After menopause, estradiol (E2) is predominately an intracrine hormone circulating in very low serum concentrations. Objective The objective of this work is to examine determinants of E2 concentrations in women beyond age 70 years. Design and Setting A cross-sectional, community-based study was conducted. Participants A total of 5325 women participated, with a mean age of 75.1 years (± 4.2 years) and not using any sex steroid, antiandrogen/estrogen, glucocorticoid, or antiglycemic therapy. Main Outcome Measures Sex steroids were measured by liquid chromatography–tandem mass spectrometry. Values below the limit of detection (LOD; E2 11 pmol/L [3 pg/mL] were assigned a value of LOD/√2 to estimate total E2. Results E2 and estrone (E1) were below the LOD in 66.1% and 0.9% of women, respectively. The median (interdecile ranges) for E1 and detectable E2 were 181.2 pmol/L (range, 88.7-347.6 pmol/L) and 22.0 pmol/L (range, 11.0-58.7 pmol/L). Women with undetectable E2 vs detectable E2 were older (median age 74.1 years vs 73.8, P = .02), leaner (median body mass index [BMI] 26.8 kg/m2 vs 28.5, P < .001), and had lower E1, testosterone and DHEA concentrations (P < .001). A linear regression model, including age, BMI, E1, and testosterone, explained 20.9% of the variation in total E2, but explained only an additional 1.2% of variation over E1 alone. E1 and testosterone made significant contributions (r2 = 0.162, P < .001) in a model for the subset of women with detectable E2. Conclusions Our findings support E1 as a principal circulating estrogen and demonstrate a robust association between E1 and E2 concentrations in postmenopausal women. Taken together with prior evidence for associations between E1 and health outcomes, E1 should be included in studies examining associations between estrogen levels and health outcomes in postmenopausal women.

scholarly journals Detection of Antimicrobial Residues in Poultry Litter: Monitoring a Risk through a Selective and Sensitive HPLC–MS/MS Method

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1399
Author(s):  
Karina Yévenes ◽  
Ekaterina Pokrant ◽  
Lina Trincado ◽  
Lisette Lapierre ◽  
Nicolás Galarce ◽  
...  
Keyword(s):  
High Performance ◽  
Limit Of Detection ◽  
Poultry Litter ◽  
Chromatography Tandem Mass Spectrometry ◽  
Antimicrobial Residues ◽  
Field Samples ◽  
Liquid Chromatography Tandem Mass ◽  
Commercial Poultry ◽  
Agriculture Fertilizer ◽  
And Control

Tetracyclines, sulphonamides, and quinolones are families of antimicrobials (AMs) widely used in the poultry industry and can excrete up to 90% of AMs administrated, which accumulate in poultry litter. Worryingly, poultry litter is widely used as an agriculture fertilizer, contributing to the spread AMs residues in the environment. The aim of this research was to develop a method that could simultaneously identify and quantify three AMs families in poultry litter by high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS). Samples of AMs free poultry litter were used to validate the method according to 657/2002/EC and VICH GL49. Results indicate that limit of detection (LOD) ranged from 8.95 to 20.86 μg kg−1, while limits of quantitation (LOQ) values were between 26.85 and 62.58 µg kg−1 of tetracycline, 4-epi-tetracycline, oxytetracycline, 4-epi-oxytetracycline, enrofloxacin, ciprofloxacin, flumequine, sulfachloropyridazine, and sulfadiazine. Recoveries obtained ranged from 93 to 108%. The analysis of field samples obtained from seven commercial poultry flocks confirmed the adequacy of the method since it detected means concentrations ranging from 20 to 10,364 μg kg−1. This provides us an accurate and reliable tool to monitor AMs residues in poultry litter and control its use as agricultural fertilizer.

Serum diiodotyrosine—a biomarker to differentiate destructive thyroiditis from Graves’ disease

2021 ◽  
Author(s):  
Naoya Fujita ◽  
Yosuke Ono ◽  
Azusa Sano ◽  
Motohiro Kimata ◽  
Seigo Oyama ◽  
...  
Keyword(s):  
Roc Curve ◽  
Operating Characteristic ◽  
Cross Sectional Study ◽  
Curve Analysis ◽  
Diagnostic Methods ◽  
Graves Disease ◽  
Roc Curve Analysis ◽  
Cross Sectional ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

Objective: Conventional diagnostic methods are limited in their ability to differentiate destructive thyroiditis from Graves’ disease. We hypothesised that serum diiodotyrosine (DIT) and monoiodotyrosine (MIT) levels could be biomarkers for differentiating destructive thyroiditis from Graves’ disease. Design: Patients with destructive thyroiditis (n = 13) and Graves’ disease (n = 22) were enrolled in this cross-sectional study. Methods: We assayed the serum DIT and MIT levels using liquid chromatography-tandem mass spectrometry. A receiver operating characteristic (ROC) curve analysis was used to determine the sensitivity and specificity of the serum DIT and MIT levels as biomarkers for differentiating destructive thyroiditis from Graves’ disease. Results: The serum DIT and MIT levels were significantly higher in patients with destructive thyroiditis than in those with Graves’ disease. The ROC curve analysis showed that the serum DIT levels (≥ 359.9 pg/mL) differentiated destructive thyroiditis from Graves’ disease, significantly, with 100.0% sensitivity and 95.5% specificity (P < .001). The diagnostic accuracy of the serum MIT levels (≥119.4 pg/mL) was not as high as that of the serum DIT levels (sensitivity, 84.6%; specificity, 77.3%; P = .001). Conclusions: The serum DIT levels may serve as a novel diagnostic biomarker for differentiating destructive thyroiditis from Graves’ disease.

scholarly journals Quantitative LC/MS-MS Determination of Sulfonamides and Some Other Antibiotics in Honey

2002 ◽  
Vol 85 (4) ◽  
pp. 853-860 ◽  
Author(s):  
Anton Kaufmann ◽  
Sven Roth ◽  
Bianca Ryser ◽  
Mirjam Widmer ◽  
Dominik Guggisberg
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Rapid Method ◽  
Limit Of Detection ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

Abstract A simple and rapid method was developed for the determination of 20 antibiotics (sulfonamides, tetracyclines, and flumequine) in honey by liquid chromatography tandem mass spectrometry. The proposed method is sensitive (limit of detection 0.5 to 10 ppb for the various antibiotics) and selective. A hydrolysis step ensures the liberation of sugar-bound sulfonamides. The approach has been used to analyze some 300 honey samples. A number of them were found to have exceeded the Swiss limit of 50 ppb.

scholarly journals Multi-Class Determination of 64 Illicit Compounds in Dietary Supplements Using Liquid Chromatography–Tandem Mass Spectrometry

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4399
Author(s):  
Dasom Shin ◽  
Hui-Seung Kang ◽  
Hyungsoo Kim ◽  
Guiim Moon
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Dietary Supplements ◽  
Limit Of Detection ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Relative Standard ◽  
Liquid Chromatography Tandem Mass

In this work, liquid chromatography–tandem mass spectrometry (LC-MS/MS) method was developed and validated for screening and confirmation of 64 illicit compounds in dietary supplements. The target compounds were illegally used pharmaceutical drugs, prohibited compounds, and not authorized ingredients for different therapeutics (sexual enhancement, weight loss, muscular strengthening, and relaxing products). The validation procedure was performed to evaluate selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision according to the Association of Official Analytical Chemists guidelines. The linearity was >0.98 in the range of 0.5–200 µg L−1. The LOQs were in the range 1–10 µg kg−1 for all target compounds. The accuracy (expressed as recovery) was 78.5–114%. The precision (expressed as the relative standard deviation) was below 9.15%. The developed method was applied for the determination of illicit compounds in dietary supplements collected from websites. As a result, the total detection rate was 13.5% (27 samples detected in 200 samples). The concentrations of detected samples ranged from 0.51 to 226 mg g−1. The proposed methodology is suitable for monitoring the adulteration of illicit compounds in dietary supplements.

scholarly journals Preparation of an immunoaffinity chromatography column for chloramphenicol binding

2016 ◽  
Vol 19 (4) ◽  
pp. 14-23
Author(s):  
Thinh Duc Nguyen ◽  
Thu Thi Nguyet Nguyen ◽  
Diem Ngoc Duong ◽  
Son Pham Ngoc Chu ◽  
Thuoc Linh Tran
Keyword(s):  
Limit Of Detection ◽  
Immunoaffinity Chromatography ◽  
Loading Capacity ◽  
Tandem Mass ◽  
Rabbit Antibody ◽  
Limit Of Quantification ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
Chromatography Columns ◽  
Cap Analysis

Anti-chloramphenicol rabbit antibody was covalently bound to Sepharose CL 4B-CNBr gel at 5, 10 and 15 mg antibody per mL gel and was fed into columns to prepare three respective immunoaffinity chromatography columns for chloramphenicol (CAP) binding. Examination of CAP-binding efficiency of these columns being fed with 0.5, 1 and 10 ng CAP showed that the column with 10 mg antibody per ml gel (IAC-CAP-10 column) could bind more than 90 % of the CAP amount having been fed into the column at all three examined CAP amounts. This IAC-CAP-10 column showed a coefficient of variants (CV) between columns upon CAP binding of 5.18 % for 1 ng fed CAP and 1.98 % for 10 ng, respectively, a loading capacity of 153,37 ± 10,32 ng CAP, stable CAP-binding performance during at least 2 years of preservation at 4 °C. The coupling of this IAC-CAP-10 column with liquid chromatography - tandem mass spectrometry LC MS/MS could make CAP analysis become possible with a limit of detection LOD of 0.033 ng and a limit of quantification LOQ of 0.101 ng. The column could also bind to the other two phenicol antibiotics: florfenicol and thiamphenicol with a binding efficiency of 90.73 % for florfenicol and 84.29 % for thiamphenicol.

scholarly journals MEETING SOCIAL NEEDS TO IMPROVE HEALTH OUTCOMES: PARTNERSHIPS BETWEEN COMMUNITY-BASED ORGS AND HEALTH CARE

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S499-S500
Author(s):  
Traci L Wilson ◽  
Suzanne R Kunkel ◽  
Jane Straker ◽  
Marisa Scala-Foley ◽  
Elizabeth Blair
Keyword(s):  
Health Care ◽  
Health Outcomes ◽  
Social Services ◽  
Health Care Providers ◽  
Health Care Use ◽  
Social Needs ◽  
Care Providers ◽  
Community Based ◽  
Cross Sectional ◽  
Improve Health

Abstract Unmet social needs negatively affect individual and population health, and better integration of community-based supports and health systems is a promising approach to improve health outcomes and avoid unnecessary health care use. Community-based organizations (CBOs) such as Area Agencies on Aging (AAAs) and Centers for Independent Living (CILs), as providers and coordinators of social services, are well-positioned within their communities to coordinate care and provide for unmet social needs. Partnerships between CBOs and health care entities have clear potential to improve health care outcomes while also reducing expenditures. This paper will present a cross-sectional analysis of a national survey of AAAs, CILS, and other CBOs at two time points (2017: n=593; 2018: n=763) to understand the extent, type, and evolution of CBO engagement with health care providers. In addition, longitudinal analysis (n=374) shows movement at the organization level: 33% of organizations who did not have a contract at T1 but were pursuing one had achieved a contract by T2. This presentation will: describe details of the services delivered, contracting arrangements, and populations served under CBO/health care contracts, as well as challenges experienced by CBOs; examine differences by state and organizational structure; and discuss the implications of state policy on integrated care and contracting.

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