Coupled Plasma Dynamic Reaction Cell Research Articles

Preterm Birth and Metal Mixture Exposure among Pregnant Women from the Navajo Birth Cohort Study.

Preterm birth (PTB), defined as birth before 37 wk gestation, is associated with hypertension, diabetes, inadequate prenatal care, unemployment or poverty, and metal exposure. Indigenous individuals are more likely to have maternal risk factors associated with PTB compared with other populations in the United States; however, the role of environmental metals on PTB among pregnant Indigenous women remains uncertain. Previous research identified associations between PTB and individual metals, but there is limited investigation on metal mixtures and this birth outcome. We used a mixtures analysis framework to investigate the association between metal mixtures and PTB among pregnant Indigenous women from the Navajo Birth Cohort Study (NBCS). Maternal urine and blood samples were collected at the time of study enrollment and analyzed for metals by inductively coupled plasma dynamic reaction cell mass spectrometry. Bayesian Profile Regression was used to identify subgroups (clusters) of individuals with similar patterns of coexposure and to model association with PTB. Results indicated six subgroups of maternal participants with distinct exposure profiles, including one group with low exposure to all metals and one group with total arsenic, cadmium, lead, and uranium concentrations exceeding representative concentrations calculated from the National Health and Nutrition Examination Survey (NHANES). Compared with the reference group (i.e., the lowest exposure subgroup), the subgroup with the highest overall exposure had a relative risk of PTB of 2.9 times (95% credible interval: 1.1, 6.1). Exposures in this subgroup were also higher overall than NHANES median values for women 14-45 years of age. Given the wide range of exposures and elevated PTB risk for the most exposed subgroups in a relatively small study, follow-up investigation is recommended to evaluate associations between metal mixture profiles and other birth outcomes and to test hypothesized mechanisms of action for PTB and oxidative stress caused by environmental metals. https://doi.org/10.1289/EHP10361.

Human serum albumin-bound selenium (Se-HSA) in serum and its correlation with other selenium species

IntroductionSelenium (Se) is a trace element with different toxicological and nutritional properties according to its chemical forms. Among the wide range of selenium species, human serum albumin-bound selenium (Se-HSA) has still uncertain composition in terms of organic or inorganic selenium species. This study aimed at investigating the relation between Se-HSA levels with total selenium and the specific organic and inorganic selenium species. MethodsWe determined levels of total selenium and selenium species in serum of participants enrolled in two populations of the Emilia-Romagna region, in Northern Italy. Anion exchange chromatography coupled with inductively coupled plasma dynamic reaction cell mass spectrometry was used as quantification method. Correlations between Se-HSA and the other selenium compounds were analyzed using linear regression and restricted cubic spline regression models, adjusted for potential confounders. ResultsThe first cohort comprised 50 participants (men/women: 26/24) with median (interquartile range, IQR) age 50 (55−62) years, while the second was composed of 104 participants (M/W: 50/54), median (IQR) age 48 (44−53) years. Median (IQR) levels of total selenium were 118.5 (109−136) µg/L and 116.5 (106−128) µg/L, respectively, while Se-HSA was 25.5 µg/L (16.2–51.5) and 1.1 (0.03–3.1) µg/L, respectively. In both populations, Se-HSA was positively associated with inorganic selenium species. Conversely, Se-HSA was inversely associated with organic selenium, especially with selenoprotein P-bound-Se (Se-SELENOP) and less strongly with selenomethionine-bound-Se (Se-Met), while the relation was null or even positive with other organic species. Evaluation of non-linear trends showed a substantially positive association with inorganic selenium, particularly selenite, until a concentration of 30 µg/L, above which a plateau was reached. The association with Se-SELENOP was inverse and strong until 100 µg/L, while it was almost null at higher levels. ConclusionsOur findings seem to indicate that Se-HSA incorporates more selenium when circulating levels of inorganic compounds are higher, thus supporting its mainly inorganic nature, particularly at high circulating levels of selenite.

Relationship between Serum Selenium Level and Self-Reported History of Kidney Stone.

A relationship may exist between selenium and kidney calculi, but there is a lack of research in this field at present. Our study explored the relationship between the serum selenium level and a medical history of adult kidney calculi. We utilized data from the National Health and Nutrition Examination Survey conducted between 2011 and 2016. Participants self-reported their history of kidney stones, while serum selenium levels were measured using inductively coupled plasma dynamic reaction cell mass spectrometry. Our findings indicate a negative correlation between serum selenium levels and the risk of kidney stone history. In the multiple-adjusted model, the lowest serum selenium level group had a higher risk than the other groups. The odds ratio (95% confidence interval) of ever having kidney stones for the highest serum selenium level group was 0.54 (0.33-0.88). In the results of stratified analysis, this relationship was still significant in the groups of women and those 40-59 years. We also found that as a nonlinear dose-response relationship between serum selenium levels and the history of kidney stones disease. In our research, we found that people with higher serum selenium levels had a lower risk of having a history of kidney stones. We concluded that selenium may have a protective effect on kidney stones. In the future, more population studies are needed to explore the relationship between selenium and kidney stones.

Association between serum copper, zinc and their ratio and handgrip strength among adults: a study from National Health and Nutrition Examination Survey (NHANES) 2011-2014.

Evidence for the association between serum copper and zinc status and handgrip strength is very limited only in several observational studies with study participants of specific population or a narrower age range. The aim of this study was to evaluate the association between serum copper, zinc and their ratio and handgrip strength in the general population. This study included adult participants aged 20-80years with complete data of serum copper and zinc status and handgrip strength from NHANES 2011-2014. Handgrip strength was calculated as the average of the maximum measure obtained in each hand with a grip strength dynamometer and corrected using BMI. Serum copper and zinc levels were measured using inductively coupled plasma dynamic reaction cell mass spectrometry, and their ratios were calculated. The multivariable linear regression and restricted cubic spline models were used. Serum copper level was inversely associated with BMI-corrected handgrip strength, and the beta coefficients (95% confidence intervals) comparing the second, third, and fourth to the lowest quartiles of serum copper level were - 0.17kg (- 0.26; - 0.08), - 0.22kg (- 0.32; - 0.13), and - 0.36kg (- 0.44; - 0.28), respectively (P for trend < 0.001). Non-linear association was detected between serum copper level and BMI-corrected handgrip strength (P < 0.01). Consistent with serum copper, serum copper/zinc ratio was inversely associated with BMI-corrected handgrip strength. However, no significant associations were observed between serum zinc level and BMI-corrected handgrip strength (all P > 0.05). Higher serum copper level and copper/zinc ratios were significantly associated with lower handgrip strength. Further research is needed to address related issues.

Association of Urinary Iodine Concentration with Depressive Symptoms among Adults: NHANES 2007-2018.

The association between iodine status and depressive symptoms has not been investigated in the general population. Therefore, we drew 8935 participants from the National Health and Nutrition Examination Survey (NHANES) 2007–2018 to explore their association. In NHANES, Inductively Coupled Plasma Dynamic Reaction Cell Mass Spectroscopy was utilized to measure urinary iodine concentration (UIC), and Patient Health Questionnaire-9 was used to assess depressive symptoms. Meanwhile, we fitted logistic regression and restricted cubic spline models. We found that high UIC was associated with a higher prevalence of depressive symptoms than the normal UIC group (OR: 1.50, 95% CI: 1.04–2.16). This association was particularly pronounced and further strengthened among females (OR: 1.90, 95% CI: 1.19–3.01) and participants aged 40–59 (OR: 1.90, 95% CI: 1.11–3.25). Moreover, we found that low UIC was associated with a high prevalence of depressive symptoms among females (OR: 1.50, 95% CI: 1.02–2.18). Moreover, the dose-response relationship between UIC and depressive symptoms presented a general trend of decreased, steady transiently, and then increased. We found that participants with high UIC had a higher prevalence of depressive symptoms than those with normal UIC. Meanwhile, we also found that females with low UIC had higher odds of reporting depressive symptoms.

Age features and reference intervals for the concentrations of some essential and toxic elements in laying hens.

Background and Aim:Micronutrient imbalances pose a severe threat to the health and productivity of livestock and poultry. In this regard, a further stage in feeding science development will control and optimize the intake of mineral substances, including determining the elemental composition in some biosubstrates. One of these biosubstrates can be a feather. However, the amount of available information on the content of trace elements in laying hens is limited, complicating the laboratory data interpretation. Therefore, this study established reference intervals for the concentrations of the main essential and toxic elements in laying hens in different periods of ontogenesis.Materials and Methods:The study was conducted on clinically healthy Hisex Brown laying hens at the age of 10 (n=150), 30 (n=150), 120 (n=150), 150 (n=150), and 210 (n=150) days. All examined birds were born and raised on the territory of the South Ural biogeochemical province of Russia. The sampling of feathers was carried out by plucking the flight feathers of the wing. Inductively coupled plasma dynamic reaction cell mass spectrometry determined the elemental composition of the feather according to 25 parameters.Results:The results showed that at the minimum age (10 days), the highest concentrations of chemical elements were observed in laying hens. Subsequently, as they grew older, in the period from the 30th to the 120th day, there was a significant decrease in these indicators. Later, from the 120th to the 150th day, a statistically significant increase in concentrations was replaced. Little growth and relative concentration stability were observed in the last part of the experiment (150-210 days). Chemical element concentrations in feathers were computed in reference ranges for each age group.Conclusion:The calculated ranges of chemical element concentrations in laying hens can be used to compile norms for their content in the body; however, it is worth noting that these ranges can vary depending on the biogeochemical province of breeding and the bird’s age.

The Relationship between Metal Exposure and Chronic Obstructive Pulmonary Disease in the General US Population: NHANES 2015-2016.

The effects of metal on pulmonary function are inconsistent, and abnormal distribution of metals can decrease lung function. However, the effects of metals exposure on chronic obstructive pulmonary disease (COPD) are still unclear. This study aims to explore the relationship between metal exposure and COPD risk. Cross-sectional data from the National Health and Nutrition Survey (NHANES) 2015–2016 was analyzed. Inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS) was used to measure the metals concentration in the blood. The multiple linear regression and restricted cubic spline (RCS) were used to analyze the relationship between metals exposure and COPD risk. In this study, 1399 participants were included, of which 107 participants were diagnosed with COPD using self-reported chronic bronchitis, emphysema, and COPD. The second and third tertiles of copper increased the COPD risk by 1.98-fold (95% CI: 1.08–3.62) and 2.43-fold (95% CI: 1.32–4.48) compared with the first tertile, using p = 0.005 for the trend after adjusting for the covariates. RCS showed a positive linear correlation between copper and COPD risk (p = 0.006 for overall association) in all participants. When stratified by sex, the multi-factor analysis showed that the third tertile of copper increased male’s COPD risk by 3.42-fold (95% CI: 1.52–7.76), with p = 0.003 for the trend, and RCS also showed a positive linear correlation (p = 0.013 for overall association). Although RCS showed that selenium can reduce the COPD risk (p = 0.008 for overall association) in males, an association between selenium and COPD was not observed (p > 0.05). Our findings suggest that a high concentration of copper may increase COPD risk in males in the general US population, and more research is needed to explore its possible mechanism of action.

Serum selenium and non-alcoholic fatty liver disease (NAFLD) in U.S. adults: National Health and Nutrition Examination Survey (NHANES) 2011-2016

BACKGROUND AND AIM: Selenium is an essential trace element that shows beneficial or adverse health effects depending on the dose. Laboratory studies suggest that high selenium may contribute to the development of non-alcoholic fatty liver disease (NAFLD). However, human evidence is limited. We evaluated the associations of serum selenium level with serum alanine aminotransferase (ALT) activity and suspected NAFLD prevalence in U.S. adults. METHODS: We conducted the cross-sectional analysis in 3,827 adults aged 20 years and older without viral hepatitis, hemochromatosis, or alcoholic liver disease who participated in the National Health and Nutrition Examination Survey (NHANES) 2011-2012, 2013-2014, and 2015-2016. Serum selenium was measured using inductively coupled plasma dynamic reaction cell mass spectrometry. Suspected NAFLD cases were defined in the presence of serum ALT 30 IU/L in men and 19 IU/L in women in the absence of other identifiable causes of liver disease. RESULTS:The median (interquartile range) of serum selenium level was 127.9 (117.9, 139.4) µg/L. Non-linear associations of serum selenium with NAFLD prevalence and serum ALT activity were observed in the generalized additive models with penalized splines. After adjustment for sociodemographic variables, lifestyle factors, body mass index, and NHANES survey cycles, positive associations were found at ~130 µg/L serum selenium with both NAFLD and ALT, whereas the associations were flattened at ~130 µg/L. CONCLUSIONS:Our findings provide evidence of non-linear associations of serum selenium with ALT activity and NAFLD prevalence. In particular, positive associations were found above serum selenium level of 130 µg/L, whereas no association was observed below this value. This finding requires confirmation in future prospective cohort studies. KEYWORDS: selenium, NAFLD, alanine aminotransferase, nutrients.

Simultaneous Quantification and Speciation of Trace Metals in Paired Serum and CSF Samples by Size Exclusion Chromatography-Inductively Coupled Plasma-Dynamic Reaction Cell-Mass Spectrometry (SEC-DRC-ICP-MS).

Background: Transition metals play a crucial role in brain metabolism: since they exist in different oxidation states they are involved in ROS generation, but they are also co-factors of enzymes in cellular energy metabolism or oxidative defense. Methods: Paired serum and cerebrospinal fluid (CSF) samples were analyzed for iron, zinc, copper and manganese as well as for speciation using SEC-ICP-DRC-MS. Brain extracts from Mn-exposed rats were additionally analyzed with SEC-ICP-DRC-MS. Results: The concentration patterns of transition metal size fractions were correlated between serum and CSF: Total element concentrations were significantly lower in CSF. Fe-ferritin was decreased in CSF whereas a LMW Fe fraction was relatively increased. The 400–600 kDa Zn fraction and the Cu-ceruloplasmin fraction were decreased in CSF, by contrast the 40–80 kDa fraction, containing Cu- and Zn-albumin, relatively increased. For manganese, the α-2-macroglobulin fraction showed significantly lower concentration in CSF, whereas the citrate Mn fraction was enriched. Results from the rat brain extracts supported the findings from human paired serum and CSF samples. Conclusions: Transition metals are strictly controlled at neural barriers (NB) of neurologic healthy patients. High molecular weight species are down-concentrated along NB, however, the Mn-citrate fraction seems to be less controlled, which may be problematic under environmental load.

Serum Copper and Zinc Levels and Colorectal Cancer in Adults: Findings from the National Health and Nutrition Examination 2011-2016.

Several studies have indicated an association between serum copper and zinc levels and colorectal cancer, but results were controversial. This study assessed the association of serum copper, zinc, and copper/zinc ratio with colorectal cancer in US adults aged 20years and older through the use of National Health and Nutrition Examination Survey (NHANES) 2011-2016 data. Serum concentrations of copper and zinc were measured using inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS). Odds ratios with 95% confidence intervals (ORs with CIs) were calculated for serum copper, zinc, and copper/zinc ratio by multivariate logistic regression. A total of 4663 participants (2320 males and 2343 females) with 24 colorectal cancer patients were included in the analyses. We did not observe a statistically significant association between serum copper level and colorectal cancer (top vs bottom quartile multivariate OR 1.71; 95% CI, 0.37-7.88; P for trend = 0.429). In addition, serum zinc level was also not significantly associated with colorectal cancer (top vs bottom quartile multivariate OR 0.72; 95% CI, 0.12-4.27; P for trend = 0.346). While in the age- and gender-adjusted model, there seemed to be a trend that participants with higher copper/zinc ratio level had higher odds of colorectal cancer than participants with lower copper/zinc ratio level; no statistically significant association was observed in multivariate-adjusted models. Our findings did not support a significant association between serum copper and zinc level and colorectal cancer risk in the general US population. Furthermore, large longitudinal studies should be needed to confirm these findings.

Associations of multiple metals with bone mineral density: A population-based study in US adults

Epidemiologic studies focus on combined effects of multiple metals on bone mineral density (BMD) are scarce. Therefore, this study was conducted to examine associations of multiple metals exposure with BMD. Data of adults aged ≥20 years (n = 2545) from the US National Health and Nutrition Examination Survey (NHANES, 2011–2016) were collected and analyzed. Concentrations of metals were measured in blood (cadmium [Cd], lead [Pb], mercury [Hg], and manganese [Mn]) and serum (copper [Cu], selenium [Se], and zinc [Zn]) using inductively coupled plasma mass spectrometry and inductively coupled plasma dynamic reaction cell mass spectrometry, respectively. The weighted quantile sum (WQS) and Bayesian kernel machine regression (BKMR) models were performed to determine the joint effects of multiple metals exposure on lumbar and total BMD. The linear regression analyses showed Pb was negatively associated with BMDs. The WQS regression analyses revealed that the WQS index was inversely related to lumbar (β = −0.022, 95% CI: −0.036, −0.008) and total BMD (β = −0.015, 95% CI: −0.024, −0.006), and Se, Mn, and Pb were the main contributors for the combined effects. Additionally, nonlinear dose–response relationships between Pb, Mn, and Se and BMD, as well as a synergistic interaction of Pb and Mn, were found in the BKMR analyses. Our findings suggested co-exposure to Cd, Pb, Hg, Mn, Cu, Se, and Zn (above their 50th percentiles) was associated with reduced BMD, and Pb, Mn, and Se were the main contributors driving the overall effects.

Serum Copper and Zinc Concentrations and Cognitive Impairment in Older Adults Aged 60 Years and Older.

Epidemiological evidence on serum zinc and copper and cognitive impairment in older adults are not consistent. Results on serum zinc and copper and cognitive impairment in older adults from the National Health and Nutrition Examination Survey (NHANES) have not been reported. Data on serum zinc and copper and cognitive impairment from individuals ≥ 60years of age were obtained from the 2011-2014 NHANES. Serum zinc and copper concentrations were determined with inductively coupled plasma dynamic reaction cell mass spectrometry. Cognitive impairment was assessed with four cognitive tests: the Digit Symbol Substitution Test (DSST), the Animal Fluency (AF), the Consortium to Establish a Registry for Alzheimer's Disease Delayed Recall (CERAD-DR), and the Word Learning (CERAD-WL) tests. Compared with the lowest tertile of serum copper, the multivariate-adjusted odds ratios of scoring low on the AF were 0.86 (0.44-1.68) in tertile 2 and 0.46 (0.25-0.82) in tertile 3, and the inverse association was also found in women. No association was found between serum copper and the DSST, CERAD-DR, and CRAD-WL, respectively. Compared with the lowest tertile of serum zinc, the multivariate-adjusted odds ratios of scoring low on the DSST were 0.83 (0.37-1.90) in tertile 2 and 0.42 (0.22-0.80) in tertile 3, and the inverse association was also found in men. No association was found between serum zinc and the AF, CERAD-DR, and CRAD-WL, respectively. In conclusion, serum copper and zinc were associated with certain cognitive performance tests among older adults, and the causality deserves to be confirmed further.

Serum zinc concentrations and prediabetes and diabetes in the general population.

The association between serum zinc and diabetes development remains uncertain. We examined the associations between serum zinc and prediabetes and diabetes, and adult participants (≥ 20years) from the 2011-2016 National Health and Nutrition Examination Survey. Serum zinc concentrations were measured with inductively coupled plasma dynamic reaction cell mass spectrometry. Prediabetes and diabetes were defined through questionnaires and fasting plasma glucose and hemoglobin A1c levels. Weighted logistic regression and restricted cubic splines were adopted to explore the dose-response relationships between serum zinc concentrations and prediabetes and diabetes. Comparing the highest to lowest quartile of serum zinc concentrations, the multivariable-adjusted odds ratio (95% confidence interval) of prediabetes and diabetes was 3.24 (2.33-4.52, Pfor trend < 0.01) and 1.64 (1.27-2.11, Pfor trend < 0.01), respectively. In stratified analysis by sex, the association between serum zinc concentrations and prediabetes was found in both men (3.83 (2.60-5.66), Pfor trend < 0.01) and women (2.41 (1.51-3.87), Pfor trend < 0.01), and the association between serum zinc concentrations and diabetes was also found in both men (2.05 (1.34-3.13), Pfor trend < 0.01) and women (1.65 (1.07-2.56), Pfor trend = 0.15). The association between serum zinc and prediabetes was consistent in stratified analyses by body mass index and hypertension, and the association with diabetes was also found in subjects with hypertension. Restricted cubic splines showed that the relationships between serum zinc concentrations and prediabetes and diabetes were linear, respectively. In conclusion, serum zinc concentrations were positively associated with prediabetes and diabetes in the general population, and the associations were linear. The findings need to be confirmed by prospective cohort studies.

Serum selenium and non-alcoholic fatty liver disease (NAFLD) in U.S. adults: National Health and Nutrition Examination Survey (NHANES) 2011–2016

BackgroundSelenium is an essential trace element that shows beneficial or adverse health effects depending on the dose. Laboratory studies suggest that high selenium may contribute to the development of non-alcoholic fatty liver disease (NAFLD). However, human evidence is limited. We evaluated the associations of serum selenium level with serum alanine aminotransferase (ALT) activity and suspected NAFLD prevalence in U.S. adults. MethodsWe conducted the cross-sectional analysis in 3827 adults aged 20 years and older without viral hepatitis, hemochromatosis, or alcoholic liver disease who participated in the National Health and Nutrition Examination Survey (NHANES) 2011–2012, 2013–2014, and 2015–2016. Serum selenium was measured using inductively coupled plasma dynamic reaction cell mass spectrometry. Suspected NAFLD cases were defined in the presence of serum ALT >30 international units (IU)/L in men and >19 I.U./L in women in the absence of other identifiable causes of liver disease. ResultsThe median (interquartile range) of serum selenium level was 127.9 (117.9, 139.4) μg/L. Non-linear associations of serum selenium with NAFLD prevalence and serum ALT activity were observed in the generalized additive models with penalized splines. After adjustment for sociodemographic variables, lifestyle factors, body mass index, and NHANES survey cycles, positive associations were found at > ~130 μg/L serum selenium with both NAFLD and ALT, whereas the associations were flattened at < ~130 μg/L. ConclusionsOur findings provide evidence of non-linear associations of serum selenium with ALT activity and NAFLD prevalence. In particular, positive associations were found above serum selenium level of 130 μg/L, whereas no association was observed below this value. This finding requires confirmation in future prospective cohort studies.

Maternal and childhood exposure to inorganic arsenic and airway allergy – A 15-Year birth cohort follow-up study

BackgroundThe prevalence of allergic diseases in children has increased globally. Early-life exposure to inorganic arsenic has been found to be associated with impaired immune function and decreased lung function in children; however, the results are inconsistent. We aimed to evaluate the effect of prenatal and childhood exposure to inorganic arsenic on allergic diseases in children, through a 15-year follow-up birth cohort study, conducted in central Taiwan. MethodsChildren born to women enrolled in the Taiwan Maternal and Infant Cohort Study (TMICS-pilot) from December 2000 to November 2001 were recruited and followed every 2–3 years until the age of 14 years. Urinary specimens were collected in the pregnant women during the 3rd trimester and the followed children. Diagnoses of allergic diseases were based on physician diagnoses using the International Study of Asthma and Allergies in Childhood questionnaire. Urinary arsenic speciation was performed using high-performance liquid chromatography and inductively coupled plasma dynamic reaction cell mass spectrophotometry. ResultsOf the 261 children from 358 mother-infant pairs for this study, those with asthma and allergic rhinitis reported a higher prevalence of maternal allergy (49.47%) than did non-allergic children (29.81%). In the fully adjusted model, levels of maternal urine (iAs + MMA + DMA) greater than the median were found to be significantly associated with an increased risk of asthma (OR = 4.28; 95% CI 1.32, 13.85). Levels of urinary (iAs + MMA + DMA) in children higher than the median were associated with an increased risk of allergic rhinitis (OR = 2.26; 95% CI 1.20, 4.26). ConclusionPrenatal and childhood exposure to inorganic arsenic were found to be significantly associated with the occurrence of asthma and allergic rhinitis in children, respectively. Further large cohort follow-up studies are important to validate the association between inorganic arsenic exposure and allergic diseases in children.

Development of a pregnancy-specific reference material for thyroid biomarkers, vitaminD, and nutritional trace elements in serum.

Matrix differences among serum samples from non-pregnant and pregnant patients could bias measurements. Standard Reference Material 1949, Frozen Human Prenatal Serum, was developed to provide a quality assurance material for the measurement of hormones and nutritional elements throughout pregnancy. Serum from non-pregnant women and women in each trimester were bottled into four levels based on pregnancy status and trimester. Liquid chromatography tandem mass spectrometry (LC-MS/MS) methods were developed and applied to the measurement of thyroid hormones, vitamin D metabolites, and vitamin D-binding protein (VDBP). Copper, selenium, and zinc measurements were conducted by inductively coupled plasma dynamic reaction cell MS. Thyroid stimulating hormone (TSH), thyroglobulin (Tg), and thyroglobulin antibody concentrations were analyzed using immunoassays and LC-MS/MS (Tg only). Certified values for thyroxine and triiodothyronine, reference values for vitamin D metabolites, VDBP, selenium, copper, and zinc, and information values for reverse triiodothyronine, TSH, Tg, and Tg antibodies were assigned. Significant differences in serum concentrations were evident for all analytes across the four levels (p≤0.003). TSH measurements were significantly different (p<0.0001) among research-only immunoassays. Tg concentrations were elevated in research-only immunoassays vs. Federal Drug Administration-approved automated immunoassay and LC-MS/MS. Presence of Tg antibodies increased differences between automated immunoassay and LC-MS/MS. The analyte concentrations' changes consistent with the literature and the demonstration of matrix interferences in immunoassay Tg measurements indicate the functionality of this material by providing a relevant matrix-matched reference material for the different stages of pregnancy.

The Association Between Maternal and Umbilical Cord Selenium Status and Fetal and Infant Growth in a Birth Cohort in Dhaka, Bangladesh

Abstract Objectives To estimate the associations of maternal and fetal selenium status [whole blood selenium (WBSe), serum selenium (SerumSe) and selenoprotein P (SEPP1)] with infant growth at birth and 12 months. Methods This study included a sub-sample from the randomized, placebo-controlled, multi-arm Maternal Vitamin D for Infant Growth trial in Dhaka, Bangladesh (n = 986). Selenium markers were measured in maternal and cord blood at delivery and scaled to one standard deviation for analyses. WBSe and SerumSe were analyzed by inductively coupled plasma dynamic reaction cell mass spectrometry. SEPP1 was analysed by enzyme-linked immunoassay. Growth outcomes of interest were weight-for-gestational age z score (WAZ), low birthweight (LBW, &amp;lt;1500 g) and small for gestational age (SGA) based on measurements within 48 hours of birth, and infant length-for-gestational-age (LAZ), weight-for-length (WFL) and head circumference-for-gestational age (HCAZ) z scores at birth and 12 months. Associations were estimated by multivariable linear and modified Poisson regression models, adjusting for vitamin D and other potential confounders. Results Maternal SerumSe and SEPP1 were not associated with any of the growth outcomes at birth or at 12 months. None of the markers were associated with growth outcomes at 12 months. In adjusted models, higher maternal WBSe (1 SD = 18.5 ug/L) was associated with lower WAZ (β = −0.09, 95% CI: −0.168, −0.007) and an increased risk of LBW (RR: 1.20, 95% CI: 1.03, 1.39). Higher cord WBSe (1 SD = 23.2 ug/L) was associated with lower LAZ at birth (β = −0.089, 95% CI: −0.176, −0.001), lower WAZ (β = −0.10, 95% CI: −0.176, −0.023) and a higher risk of SGA (RR: 1.18, 95% CI: 1.07, 1.31). Higher cord SEPP1 (1 SD = 533.6 ng/mL) was associated with higher LAZ at birth (β = 0.098, 95% CI: 0.018, 0.178), higher WAZ (β = 0.086, 95% CI: 0.019, 0.154) and a decreased risk of SGA (RR: 0.87, 95% CI: 0.79, 0.97). Conclusions Both maternal and cord WBSe were negatively associated with measures of fetal growth, yet cord SEPP1 had a positive association. There were no associations with infant size at 12 months. These results do not provide evidence of a beneficial effect of higher maternal or fetal selenium status on fetal or infant growth. Yet, observed discrepancies between cord WBSe and SEPP1 require further investigation. Funding Sources This study was funded by the Bill and Melinda Gates Foundation.

Speciation Analysis of Arsenic Compounds by High-Performance Liquid Chromatography in Combination with Inductively Coupled Plasma Dynamic Reaction Cell Quadrupole Mass Spectrometry: Application for Vietnamese Rice Samples.

In this work, high-performance liquid chromatography in combination with inductively coupled plasma dynamic reaction cell quadrupole mass spectrometry was introduced and optimized for speciation analysis of five major arsenic species including arsenobetain (AsB), arsenite (As(III)), monomethylarsonic (MMA), dimethylarsenonic acid (DMA), and arsenate (As(V)) in rice samples. Five arsenic compounds were separated on a Hamilton PRP X100 strong anion-exchange column employed with the mobile phase that is compatible with mass spectrometry, containing ammonium carbonate, methanol, and disodium ethylenediaminetetraacetic acid. Arsenic compounds were detected online by inductively coupled plasma dynamic reaction cell quadrupole mass spectrometry utilizing oxygen as the reaction gas at a flow rate of 0.7 mL·min−1. Five selected arsenic species were baseline separated at the optimum experimental conditions. The excellent LOD and LOQ values of the developed method were achieved in the range of 0.5 to 2.9 μg·kg−1 and 1.7 to 9.6 μg·kg−1 for all species of arsenic, respectively. The ionization effect in plasma during chromatographic gradient elution was systematically investigated by using postcolumn injector. Arsenic compounds in rice samples were extracted by diluted nitric acid at elevated temperature. The extraction efficiency and the interconversion of target compounds during sample preparation were also assessed. The full validation of the developed method was performed by using certified reference material, BRC 211, from European Institute of Reference and Standard for speciation analysis. The recovery of all selected arsenic species was in the range of 70 to 135.5%. The validated method was also applied to analyze rice samples collected from some contaminated rice fields. The results showed that As(III), DMA, and As(V) were found in all rice samples. Average concentration (range) of inorganic arsenic and DMA in all rice samples were 130.3 (65.5–228.1) and 32 (8.2–133.01) μg·kg−1, respectively. However, total concentration of inorganic arsenic in most of investigated rice samples was below the maximum residual level according to US-FDA and European Union standards.

Serum Trace Elements and Electrolytes Are Associated with Fasting Plasma Glucose and HbA1c in Postmenopausal Women with Type 2 Diabetes Mellitus.

The primary aim of the research was to assess the level of trace elements and electrolytes in serum of postmenopausal diabetic women. Sixty-four postmenopausal women with type 2 diabetes mellitus (DM2) and 64 age- and body mass index-matched controls were examined. Serum trace elements were assessed using inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS). Fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) levels were evaluated using Randox kits. The obtained data demonstrate that DM2 patients were characterized by 42 and 34% higher FPG and HbA1c levels, respectively (p<0.001). The level of Cu and Se in diabetic postmenopausal women was increased by 10 and 15% in comparison to the respective control values (p=0.002 and <0.001). Serum Mn, Zn, and Ni concentrations were lower than the control ones by 32% (p=0.003), 8% (p=0.003), and 23% (p=0.046), respectively. FPG and HbA1c levels directly correlated with serum Se (p<0.001) and Cu (p=0.014 and p=0.028) concentrations and inversely related to Zn (p<0.001) and Tl (p=0.023 and p=0.029) levels. Multiple regression analysis demonstrated a significant association between serum Zn and Se and FPG and HbA1c levels. It is proposed that Zn and Se play an important role in DM2 pathogenesis. Further studies are required to assess the intimate mechanisms of the observed differences.

Evaluation of tissue metal and trace element content in a rat model of non-alcoholic fatty liver disease using ICP-DRC-MS

The primary objective of the study was to assess the level of metals and trace elements in liver, serum, and hair of rats with diet-induced non-alcoholic fatty liver disease (NAFLD) using inductively coupled plasma dynamic reaction cell mass spectrometer (ICP-DRC-MS). 56 female 3-months-old Wistar rats divided into two equal groups were fed either standard (10% calories from fat) or high-fat high-carbohydrate diet (60% calories from fat in chow and 10% sucrose solution) for 6 weeks. Serum was examined for insulin resistance markers, lipid profile, and alanine aminotransferase (ALT) activity. Liver histology was assessed after hematoxylin and eosin staining. Metal and trace element concentrations were assessed by means of ICP-DRC-MS. Overfed animals were characterized by higher values of morphometric parameters. Liver examination revealed large and small droplet steatosis, hepatocyte ballooning and necrosis, being characteristic for NAFLD. Animals with NAFLD were characterized by insulin resistance, atherogenic changes of lipid profile and increased ALT activity. Significantly decreased hepatic Co, Cu, I, Li, Mn, Se, Zn levels were observed in rats with NAFLD. At the same time, only hepatic Mn and Se levels remained decreased after adjustment for total protein. Overfed animals were characterized by significantly lower I, Li, and Mn levels in blood serum, whereas concentration of Co, Se, V, and Sr exceeded the control values. In general, the results of the study demonstrate that NAFLD significantly affects metal and trace element status in experimental animals.