scholarly journals SAT-027 Comparison of Estradiol by Mass Spectrometry Versus Immunoassay in Women Undergoing Menopause: Study of Womens Health Across the Nation (SWAN)

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Nanette F Santoro ◽  
Richard Joseph Auchus ◽  
Gail Greendale ◽  
Bill L Lasley ◽  
Daniel S McConnell ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Random Number ◽  
Limit Of Detection ◽  
Excellent Correlation ◽  
Serum Samples ◽  
Pearson's R ◽  
Womens Health ◽  
The Relationship ◽  
Assay Detection ◽  
Pearson’S R

Abstract Serum estradiol (E2) concentrations in midreproductive women are easily measured using a variety of conventional immunoassays (IA). However, when women approach and traverse menopause, E2 eventually drops below levels where IA lacks sufficient sensitivity to accurately measure E2. Liquid chromatography and tandem mass spectrometry (LC/MS/MS) has become the standard method for assessing steroid hormones, especially when circulating concentrations are low. We evaluated the relationship between IA and LC/MS/MS E2 measurements in a cohort of women taken from the Study of Womens Health Across the Nation (SWAN) to assess the degree of agreement between the two methods and to determine the level of E2 at which IA becomes unreliable. Methods: 315 serum samples that had been previously measured for E2 using IA were re-analyzed using LC/MS/MS performed by one of the authors (RA). In this original set, E2 levels that were below the limit of assay detection (LLD, 6 pg/ml) were interpolated as a random number between 0 and the LLD. Agreement between all 315 samples was assessed using both Pearson and Spearman correlation. The analysis was repeated excluding the subset of specimens that were below the lower limit of detection (LLD) for the IA E2 assay (6 pg/ml; N=176), and a third set of correlations was obtained for specimens that measured <15 pg/ml by IA but were above the 6 pg/ml LLD (N=82). Results: The overall dataset (N=315) demonstrated excellent agreement between IA and LC/MS/MS with a Pearson’s r and Spearmans r of 0.98 AND 0.60, respectively. When the subset of 176 samples above the LLD were assessed, Pearson’s r was 0.98 and Spearman’s r was 0.81. In contrast, when specimens measuring 6–15 pg/ml by IA were compared to LC/MS/MS, Pearson’s r was -0.03 and Spearman’s r was 0.09, indicating a complete loss of relationship between the two methods. Conclusions: The IA used by SWAN (England, Clin Chem 2002; 48: 1584) and LC/MS/MS demonstrate excellent correlation for E2 measurements above 15 pg/ml. However, circulating concentrations of E2 below 15 pg/ml were not accurately measured using IA.

scholarly journals Development and validation of a mass spectrometry-based assay for quantification of insulin-like factor 3 in human serum

2018 ◽  
Vol 56 (11) ◽  
pp. 1913-1920 ◽  
Author(s):  
Jakob Albrethsen ◽  
Hanne Frederiksen ◽  
Anna-Maria Andersson ◽  
Ravinder Anand-Ivell ◽  
Loa Nordkap ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Cell Function ◽  
Limit Of Detection ◽  
Chemical Reduction ◽  
Pearson Correlation ◽  
Serum Samples ◽  
Clinical Role ◽  
Adult Men ◽  
Deming Regression ◽  
A Chain

Abstract Background: The circulating level of the peptide hormone insulin-like factor 3 (INSL3) is a promising diagnostic marker reflecting Leydig cell function in the male. Few commercial immunoassays of varying quality exist. Therefore, we decided to develop and validate a precise method for quantification of INSL3 by mass spectrometry. Methods: We developed an assay in which the INSL3 A-chain is released from the INSL3 A-B heterodimer by chemical reduction and alkylation. The alkylated INSL3 A-chain is quantitated by liquid chromatography-tandem mass spectrometry (LC-MS/MS), as substitute for serum INSL3. The method was compared to a validated and sensitive in-house serum INSL3 immunoassay using 97 serum samples from 12 healthy boys during pubertal transition. Adult levels were determined based on sera from 72 adult healthy males aged 18–40 years. Results: An LC-MS/MS assay with limit of detection and limit of quantification (LOQ) of 0.06 and 0.15 ng/mL, respectively, and intra-assay CVs <9% in the relevant ranges was obtained. The LC-MS/MS compared well with the in-house immunoassay (Deming regression slope: 1.28; Pearson correlation: R=0.86). INSL3 concentrations increased with pubertal maturation in healthy boys. INSL3 concentrations were above the LOQ in all samples from the adult men. The mean (±2 SD range)for serum INSL3 concentrations in the adult men was 2.2 (0.5–3.9) ng/mL. Conclusions: We have developed a robust and sensitive method suitable for quantitation of serum INSL3 in a clinical setting using LC-MS/MS instrumentation available in modern clinical laboratories. The method paves the way for future studies into the clinical role of serum INSL3 measurements.

scholarly journals Development and validation of sensitive method for determination of serum cotinine in smokers and nonsmokers by liquid chromatography/atmospheric pressure ionization tandem mass spectrometry

1997 ◽  
Vol 43 (12) ◽  
pp. 2281-2291 ◽  
Author(s):  
John T Bernert ◽  
Wayman E Turner ◽  
James L Pirkle ◽  
Connie S Sosnoff ◽  
James R Akins ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Atmospheric Pressure ◽  
High Resolution Mass Spectrometry ◽  
Limit Of Detection ◽  
Atmospheric Pressure Chemical Ionization ◽  
Current Method ◽  
Specific Method ◽  
Tandem Mass ◽  
Serum Samples ◽  
Serum Cotinine

Abstract We describe a sensitive and specific method for measuring cotinine in serum by HPLC coupled to an atmospheric pressure chemical ionization tandem mass spectrometer. This method can analyze 100 samples/day on a routine basis, and its limit of detection of 50 ng/L makes it applicable to the analysis of samples from nonsmokers potentially exposed to environmental tobacco smoke. Analytical accuracy has been demonstrated from the analysis of NIST cotinine standards and from comparative analyses by both the current method and gas chromatography/high-resolution mass spectrometry. Precision has been examined through the repetitive analysis of a series of bench and blind QC materials. This method has been applied to the analysis of cotinine in serum samples collected as part of the Third National Health and Nutrition Examination Survey (NHANES III).

scholarly journals Intellectual Property and Innovation as a Way to Enable Technological Development in the Agribusiness Sector

2021 ◽  
Vol 9 (10) ◽  
pp. 183-196
Author(s):  
Aprigio Teles Mascarenhas Neto ◽  
Maria Emilia Camargo
Keyword(s):  
Systematic Review ◽  
Intellectual Property ◽  
Technological Development ◽  
Meta Analysis ◽  
Quantitative Approach ◽  
Pearson's R ◽  
R Value ◽  
The Relationship ◽  
Pearson’S R

This article deals with intellectual property, the process of innovation and technological development in the agribusiness sector, and aims to identify and understand the relationship between these themes, in order to know whether intellectual property and innovation are able to foster technological development in this sector. The methodology is meta-analysis, of quantitative approach, preceded by bibliometry and systematic review. The overall result shows that there is a positively high correlation between intellectual property, innovation and technological development in the agribusiness sector, as the result of the meta-analysis was a Pearson's r value of 0.55.

scholarly journals Determination of flumazenil in serum by liquid chromatography-mass spectrometry: Application to kinetics study in acute diazepam overdose

2016 ◽  
Vol 73 (2) ◽  
pp. 146-151
Author(s):  
Snezana Djordjevic ◽  
Jasmina Jovic-Stosic ◽  
Vesna Kilibarda ◽  
Zoran Segrt ◽  
Natasa Perkovic-Vukcevic
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Half Life ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Serum Samples ◽  
Elimination Half Life ◽  
Elimination Half ◽  
Limit Of Quantitation

Backgound/Aim. Flumazenil is benzodiazepine receptor antagonist. It has been studied for a various indications, including reversal of sedation after surgery or diagnostic procedures, awakening of comatose patients in benzodiazepine overdose, or for symptomatic treatment of hepatic encephalopathy. Some drugs, like theophylline, may prolong its elimination half-life. Considering the long half-life of diazepam and its metabolites, concomitant use of theophylline may reduce the need for repeated dosing of flumazenil in patients with acute diazepam poisoning. The aim of this study was to introduce a reliable and accurate method for determining the concentration of flumazenil after therapeutic application in patients with acute poisoning, and using that method to assess whether the kinetics of flumazenil change in the presence of aminophylline (combination of theophylline and ethylenediamine in a 2 : 1 ratio) applied as concomitant therapy. Methods. Blood samples from patients with acute diazepam poisoning that received flumazenil at the dose of 0.5 mg, or the same dose with 3 mg/kg of body weight of aminophylline, were collected 1, 3, 10, 30, 60, 120 and 240 min after its intravenous administration. Samples were prepared by solid-phase extraction on Oasis HLB cartridges with ethylacetate as extracting agens. Flumazenil was determined by liquid chromatography with mass spectrometry (LC-MS) in single ion monitoring mode at m/z 304. Separation of flumazenil from matrix compound was performed on Lichrospher RP-8 column using the mixture of acidic acetonitrile and 20 mM of ammonium acetate in water (55 : 45) as a mobile phase. Results. The applied analitycal method showed excellent recovery (94.65%). The obtained extracts were much cleaner than the extracts obtained by the same extractant in the process of liquid-liquid extraction. The limit of detection of the LC-MS method described in this paper was 0.5 ng/mL and the limit of quantitation was 1 ng/mL. In the patients treated with both flumazenil and aminophylline, the elimination constant for flumazenil was significantly lower and the elimination half-life was longer (p < 0.05) in comparison with the same parameters in the patients who received flumazenil alone. Conclusion. The applied LC-MS method for the determination of flumazenil in serum samples of patients with acute diazepam poisoning is rapid, sensitive, precise and specific. Concomitant use with theophylline significantly prolonged elimination of flumazenil during the treatment of acute poisonings with diazepam.

scholarly journals Family Food Environment and Child Eating Behavior in a Private School of Abu Dhabi

2017 ◽  
Vol 1 (1) ◽  
pp. 24
Author(s):  
Al Amoodi Sara Ahmed Abdulla Saeed
Keyword(s):  
Eating Behavior ◽  
Private School ◽  
Food Environment ◽  
Eating Behaviour ◽  
Abu Dhabi ◽  
Pearson's R ◽  
Child Eating ◽  
The Relationship ◽  
Family Food Environment ◽  
Pearson’S R

Aim: Dietary habits developed during childhood and continued  through adulthood.    Children’s eating behaviours should be  monitorining to avoid possible  nutritional deficiencies which have been found to be strongly related to the development of future disease such as  obesity, diabetes type 2 and others. The main aim of this study is to explore the relationship between family food environment and the eating behavior during  dinnertime among children aged 4 to 6 years old in Abu Dhabi. A cross-sectional  study was carried out  that examined the relationship between family food environment and child’s  eating behaviour around dinnertime.Methods: 61 families participated in the study with their children aged 4-6 years old from a private school. They completed a questionnaire that included questions about demographics, eating behaviour and food environment.Results: 82% of the mothers were reported to be responsible for feeding the children. Most of the families had dinner together three or more times a week. Half of the children got a high score in the child’s eating behaviour scale, indicating that they had positive eating behaviour. The results also showed that children of highly educated mothers were more likely to have positive eating behaviour, compared to children of mothers with lower education (p < .05). There was a significant positive correlation between modelling of eating and child eating behaviour ( Pearson’s r = .56, p < .01), and a significant negative correlation between pressure to eat and child eating behaviour (Pearson’s r = -.35, p < .01).Conclusion: This study is in line with other studies showing that aspects in the family food environment have an influence on eating behaviour of children. Educating parents on food environment and its impact on child behaviour is crucial in order to make them able to develop feeding strategies most likely to benefit children's’  health.

scholarly journals Invisible hemolysis in serum samples interferes in NSE measurement

2019 ◽  
Vol 106 (1) ◽  
pp. 79-81
Author(s):  
Antonio Mastroianni ◽  
Rossella Panella ◽  
Daniele Morelli
Keyword(s):  
Neuron Specific Enolase ◽  
Reference Interval ◽  
Mean Value ◽  
Excellent Correlation ◽  
Free Hemoglobin ◽  
Serum Samples ◽  
Neurologic Diseases ◽  
The Relationship ◽  
Serum Neuron Specific Enolase

Introduction: The accuracy of serum neuron-specific enolase (NSE) measurements is critical, particularly in neurologic diseases and cancer. NSE measurements are compromised by slight, even invisible, hemolysis, which can produce apparently higher NSE levels, leading to inappropriate clinical decisions. In this article, we describe this issue and propose a solution for avoiding incorrect results. Methods: Twenty blood samples from donors with NSE values that were within the reference interval were considered. Experimental hemolysis was induced in vitro to examine the relationship between the degree of hemolysis and the increase in serum NSE. The data were then subjected to statistical analysis. Results: There was excellent correlation ( r2 0.953) between the degree of hemolysis and the rise in NSE concentration. Each hemolysis unit (equal to 1 mg/dL of free hemoglobin) corresponded to a mean value of 0.29 ± 0.09 ng/mL NSE that was released from red blood cells. Conclusion: The hemolysis index must be measured in every sample with no evident hemolysis before assaying it for NSE. Moreover, if the degree of hemolysis is between 5 and 30 units, the increase in NSE (from 1.5 to 9.0 ng/mL) must be calculated, and the laboratory results should be appended with comments that suggest the approximate rise in NSE.

scholarly journals MACROECONOMIC STABILITY AND TRANSPORT COMPANIES’ SUSTAINABLE DEVELOPMENT IN THE EASTERN EUROPEAN UNION

2021 ◽  
Vol 0 (0) ◽  
pp. 1-14
Author(s):  
Michał Comporek ◽  
Magdalena Kowalska ◽  
Anna Misztal
Keyword(s):  
Sustainable Development ◽  
Least Square Method ◽  
Least Square ◽  
Eastern European ◽  
Economic Policies ◽  
Ordinary Least Square ◽  
Pearson's R ◽  
The Relationship ◽  
Pearson’S R ◽  
Macroeconomic Stability

The paper’s primary aim is to evaluate the influence of macroeconomic stability on transport companies’ sustainable development in the eastern EU from 2008 to 2019. The first part discusses the theoretical problems. The empirical part includes the methodology, results of the research and conclusions. To determine the relationship between variables, we use Pearson’s R and the Ordinary Least Square Method. The contribution to knowledge is using the pentagon of macroeconomic stability to evaluate macroeconomic stabilisation’s influence on transport companies’ sustainable development. The results indicate that macroeconomic stability is one of the essential determinants of the transport companies’ sustainable development. According to Pearson’s R, the highest level of dependence is in Slovenia (0.96), Bulgaria (0.9), and Slovenia (0.83). The lowest is in Latvia (0.69). The OLS regression results indicate that the highest significance is in Slovakia (α1 = 1.994), the lowest is in Lithuania (α1 = 0.691). The states’ economic policies should favour the freedom to conduct business, create appropriate legal regulations, and support ecological investments. It is necessary to act for a stable and fair tax system, ensure access to finance. The issue is contemporary and requires further analysis.

CODEM Instrument

GeroPsych ◽  
2014 ◽  
Vol 27 (1) ◽  
pp. 23-31 ◽  
Author(s):  
Anne Kuemmel (This author contributed eq ◽  
Julia Haberstroh (This author contributed ◽  
Johannes Pantel
Keyword(s):  
Convergent Validity ◽  
Interrater Reliability ◽  
Discriminant Validity ◽  
Assessment Tool ◽  
Intraclass Correlation ◽  
Well Being ◽  
Communication Behavior ◽  
People With Dementia ◽  
Pearson's R ◽  
Pearson’S R

Communication and communication behaviors in situational contexts are essential conditions for well-being and quality of life in people with dementia. Measuring methods, however, are limited. The CODEM instrument, a standardized observational communication behavior assessment tool, was developed and evaluated on the basis of the current state of research in dementia care and social-communicative behavior. Initially, interrater reliability was examined by means of videoratings (N = 10 people with dementia). Thereupon, six caregivers in six German nursing homes observed 69 residents suffering from dementia and used CODEM to rate their communication behavior. The interrater reliability of CODEM was excellent (mean κ = .79; intraclass correlation = .91). Statistical analysis indicated that CODEM had excellent internal consistency (Cronbach’s α = .95). CODEM also showed excellent convergent validity (Pearson’s R = .88) as well as discriminant validity (Pearson’s R = .63). Confirmatory factor analysis verified the two-factor solution of verbal/content aspects and nonverbal/relationship aspects. With regard to the severity of the disease, the content and relational aspects of communication exhibited different trends. CODEM proved to be a reliable, valid, and sensitive assessment tool for examining communication behavior in the field of dementia. CODEM also provides researchers a feasible examination tool for measuring effects of psychosocial intervention studies that strive to improve communication behavior and well-being in dementia.

Ferromagnetic Resonance Biosensor for Homogeneous and Volumetric Detection of DNA

2017 ◽  
Author(s):  
Bo Tian ◽  
Peter Svedlindh ◽  
Mattias Strömberg ◽  
Erik Wetterskog
Keyword(s):  
Magnetic Nanoparticles ◽  
Ferromagnetic Resonance ◽  
Limit Of Detection ◽  
Point Of Care ◽  
Rolling Circle Amplification ◽  
Resonance Field ◽  
Isothermal Amplification ◽  
Detection Sensitivity ◽  
Serum Samples ◽  
Rolling Circle

In this work, we demonstrate for the first time, a ferromagnetic resonance (FMR) based homogeneous and volumetric biosensor for magnetic label detection. Two different isothermal amplification methods, <i>i.e.</i>, rolling circle amplification (RCA) and loop-mediated isothermal amplification (LAMP) are adopted and combined with a standard electron paramagnetic resonance (EPR) spectrometer for FMR biosensing. For RCA-based FMR biosensor, binding of RCA products of a synthetic Vibrio cholerae target DNA sequence gives rise to the formation of aggregates of magnetic nanoparticles. Immobilization of nanoparticles within the aggregates leads to a decrease of the net anisotropy of the system and a concomitant increase of the resonance field. A limit of detection of 1 pM is obtained with an average coefficient of variation of 0.16%, which is superior to the performance of other reported RCA-based magnetic biosensors. For LAMP-based sensing, a synthetic Zika virus target oligonucleotide is amplified and detected in 20% serum samples. Immobilization of magnetic nanoparticles is induced by their co-precipitation with Mg<sub>2</sub>P<sub>2</sub>O<sub>7</sub> (a by-product of LAMP) and provides a detection sensitivity of 100 aM. The fast measurement, high sensitivity and miniaturization potential of the proposed FMR biosensing technology makes it a promising candidate for designing future point-of-care devices.<br>

scholarly journals Maternal immune response and air pollution exposure during pregnancy: insights from the Early Markers for Autism (EMA) study

2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Heather E. Volk ◽  
Bo Park ◽  
Calliope Hollingue ◽  
Karen L. Jones ◽  
Paul Ashwood ◽  
...  
Keyword(s):  
Air Pollution ◽  
Intellectual Disability ◽  
Prenatal Screening ◽  
Maternal Serum ◽  
Serum Samples ◽  
Maternal Immune Activation ◽  
Early Markers ◽  
Air Pollution Exposure ◽  
Pollution Exposure ◽  
The Relationship

Abstract Background Perinatal exposure to air pollution and immune system dysregulation are two factors consistently associated with autism spectrum disorders (ASD) and other neurodevelopmental outcomes. However, little is known about how air pollution may influence maternal immune function during pregnancy. Objectives To assess the relationship between mid-gestational circulating levels of maternal cytokines/chemokines and previous month air pollution exposure across neurodevelopmental groups, and to assess whether cytokines/chemokines mediate the relationship between air pollution exposures and risk of ASD and/or intellectual disability (ID) in the Early Markers for Autism (EMA) study. Methods EMA is a population-based, nested case–control study which linked archived maternal serum samples collected during weeks 15–19 of gestation for routine prenatal screening, birth records, and Department of Developmental Services (DDS) records. Children receiving DDS services for ASD without intellectual disability (ASD without ID; n = 199), ASD with ID (ASD with ID; n = 180), ID without ASD (ID; n = 164), and children from the general population (GP; n = 414) with no DDS services were included in this analysis. Serum samples were quantified for 22 cytokines/chemokines using Luminex multiplex analysis technology. Air pollution exposure for the month prior to maternal serum collection was assigned based on the Environmental Protection Agency’s Air Quality System data using the maternal residential address reported during the prenatal screening visit. Results Previous month air pollution exposure and mid-gestational maternal cytokine and chemokine levels were significantly correlated, though weak in magnitude (ranging from − 0.16 to 0.13). Ten pairs of mid-pregnancy immune markers and previous month air pollutants were significantly associated within one of the child neurodevelopmental groups, adjusted for covariates (p < 0.001). Mid-pregnancy air pollution was not associated with any neurodevelopmental outcome. IL-6 remained associated with ASD with ID even after adjusting for air pollution exposure. Conclusion This study suggests that maternal immune activation is associated with risk for neurodevelopmental disorders. Furthermore, that prenatal air pollution exposure is associated with small, but perhaps biologically relevant, effects on maternal immune system function during pregnancy. Additional studies are needed to better evaluate how prenatal exposure to air pollution affects the trajectory of maternal immune activation during pregnancy, if windows of heightened susceptibility can be identified, and how these factors influence neurodevelopment of the offspring.

Sign in / Sign up

Export Citation Format

Share Document