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1

No association between perfluoroalkyl chemicals and hypertension in children  

PubMed Central

Background Hypertension is a leading cause of cardiovascular disease worldwide. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are perfluoroalkyl chemicals (PFCs) used in the manufacture of common consumer products and detected in the blood of the majority of Americans. Emerging biological data suggest that PFC exposure may have a role in the development of hypertension. However, the association between PFCs and hypertension has not yet been explored in humans. Therefore, we examined this association in a representative sample of US children. Methods A cross-sectional study was performed on 1,655 children from the National Health and Nutrition Examination Survey, 1999–2000 and 2003–2008. The main outcome of interest was hypertension, defined as age, height, and sex specific systolic and/or diastolic blood pressure level at the 95th percentile. Results We found no association between serum levels of PFOA and PFOS and hypertension in either unadjusted or multivariable-adjusted analyses controlling for age, sex, race-ethnicity, body mass index, annual household income, moderate activity, total serum cholesterol, and serum cotinine. Compared with the lowest quartile, the multivariable-adjusted odds ratio (95% confidence interval) of hypertension in the highest quartile of exposure was 0.69 (0.41–1.17) for PFOA and 0.77 (0.37–1.61) for PFOS (all P-trend values >0.30). Conclusion Our findings indicate that exposure to PFOA or PFOS is not significantly associated with hypertension in children at the lower PFC exposure levels typical of the general population. PMID:24520202

Geiger, Sarah Dee; Xiao, Jie; Shankar, Anoop

2014-01-01

2

40 CFR 721.10536 - Long-chain perfluoroalkyl carboxylate chemical substances.  

Code of Federal Regulations, 2014 CFR

...import) or processing of the following two long-chain perfluoroalkyl carboxylate (LCPFAC) chemical substances for use as a surfactant in aftermarket carpet cleaning products shall not be considered a significant new use subject to reporting under this...

2014-07-01

3

Serum perfluoroalkyl acids concentrations and memory impairment in a large cross-sectional study  

PubMed Central

Objectives To examine the cross-sectional association between serum perfluorooctanate (PFOA), perfuorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA) and perfluorohexane sulfonate (PFHxS) concentrations with self-reported memory impairment in adults and the interaction of these associations with diabetes status. Design Cross-sectional study. Setting Population-based in Mid-Ohio Valley, West Virginia following contamination by a chemical plant. Participants The C8 Health Project collected data and measured the serum level of perfluoroalkyl acids (PFAAs) of 21?024 adults aged 50+ years. Primary outcome measure Self-reported memory impairment as defined by the question ‘have experienced short-term memory loss?’ Results A total of 4057 participants self-reported short-term memory impairment. Inverse associations between PFOS and PFOA and memory impairment were highly statistically significant with fully adjusted OR=0.93 (95% CI 0.90 to 0.96) for doubling PFOS and OR=0.96 (95% CI 0.94 to 0.98) for doubling PFOA concentrations. Comparable inverse associations with PFNA and PFHxS were of borderline statistical significance. Inverse associations of PFAAs with memory impairment were weaker or non-existent in patients with diabetes than overall in patients without diabetes. Conclusions An inverse association between PFAA serum levels and self-reported memory impairment has been observed in this large population-based, cross-sectional study that is stronger and more statistically significant for PFOA and PFOS. The associations can be potentially explained by a preventive anti-inflammatory effect exerted by a peroxisome proliferator-activated receptor agonist effect of these PFAAs, but confounding or even reverse causation cannot be excluded as an alternative explanation. PMID:23794579

Gallo, Valentina; Leonardi, Giovanni; Brayne, Carol; Armstrong, Ben; Fletcher, Tony

2013-01-01

4

Perfluoroalkyl chemicals in vacuum cleaner dust from 39 Wisconsin homes.  

PubMed

Perfluoroalkyl chemicals (PFCs) have been used as surfactants and stain repellants in a variety of consumer products for more than 50years and there is growing concern regarding their persistence and toxicity. Human exposure to these chemicals is essentially universal in North America and researchers have linked them to a variety of health problems ranging from higher rates of cancer, to developmental and reproductive problems, and higher cholesterol levels. Major exposure pathways are food and water ingestion, dust ingestion via hand to mouth transfer. In an effort to assess residential exposure, the Wisconsin Department of Health Services tested vacuum cleaner contents from thirty-nine homes for 16 perflouroalkyl chemicals. PFOS, PFOA, PFHxS, PFHpA and PFNA were found in all of the vacuum dust samples and dust from eight homes contained all 16 PFCs included in our analysis. The most commonly detected compounds were perfluorooctanesulfonate (PFOS), perfluorohexanesulfonate (PFHxS) and perfluorooctanoic acid (PFOA) which together made up 70% of the total PFC residues in dust from these homes. Summed PFC concentrations in these dust samples ranged from 70 to 2513ng/g (median 280ng/g). Our investigation suggests that these chemicals may be ubiquitous contaminants in US homes. PMID:22542201

Knobeloch, Lynda; Imm, Pamela; Anderson, Henry

2012-08-01

5

Serum levels of perfluoroalkyl compounds in human maternal and umbilical cord blood samples  

SciTech Connect

Perfluoroalkyl compounds (PFCs) are end-stage metabolic products from industrial flourochemicals used in the manufacture of plastics, textiles, and electronics that are widely distributed in the environment. The objective of the present study was to quantify exposure to perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorodecanoic acid (PFDeA), perfluorohexane sulfonate (PFHxS), perfluoroheptanoic acid (PFHpA), and perfluorononanoic acid (PFNA) in serum samples collected from pregnant women and the umbilical cord at delivery. Pregnant women (n=101) presenting for second trimester ultrasound were recruited and PFC residue levels were quantified in maternal serum at 24-28 weeks of pregnancy, at delivery, and in umbilical cord blood (UCB; n=105) by liquid chromatography-mass spectrometry. Paired t-test and multiple regression analysis were performed to determine the relationship between the concentrations of each analyte at different sample collection time points. PFOA and PFOS were detectable in all serum samples analyzed including the UCB. PFOS serum levels (mean{+-}S.D.) were significantly higher (p<0.001) in second trimester maternal serum (18.1{+-}10.9 ng/mL) than maternal serum levels at delivery (16.2{+-}10.4 ng/mL), which were higher than the levels found in UCB (7.3{+-}5.8 ng/mL; p<0.001). PFHxS was quantifiable in 46/101 (45.5%) maternal and 21/105 (20%) UCB samples with a mean concentration of 4.05{+-}12.3 and 5.05{+-}12.9 ng/mL, respectively. There was no association between serum PFCs at any time point studied and birth weight. Taken together our data demonstrate that although there is widespread exposure to PFCs during development, these exposures do not affect birth weight.

Monroy, Rocio [Department of Obstetrics and Gynecology, McMaster University, HSC-3N52D, 1200 Main Street West, Hamilton, Ontario, L8N 3Z5 (Canada); Morrison, Katherine [Department of Pediatrics, McMaster University, HSC-3N52D, 1200 Main Street West, Hamilton, Ontario, L8N 3Z5 (Canada); Teo, Koon [Department of Medicine, McMaster University, HSC-3N52D, 1200 Main Street West, Hamilton, Ontario, L8N 3Z5 (Canada); Atkinson, Stephanie [Department of Pediatrics, McMaster University, HSC-3N52D, 1200 Main Street West, Hamilton, Ontario, L8N 3Z5 (Canada); Kubwabo, Cariton; Stewart, Brian [Chemistry Research Division, Safe Environments Programme, Health Canada, Ottawa, Ontario (Canada); Foster, Warren G. [Department of Obstetrics and Gynecology, McMaster University, HSC-3N52D, 1200 Main Street West, Hamilton, Ontario, L8N 3Z5 (Canada)], E-mail: fosterw@mcmaster.ca

2008-09-15

6

77 FR 48924 - Perfluoroalkyl Sulfonates and Long-Chain Perfluoroalkyl Carboxylate Chemical Substances; Proposed...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Animal studies of the straight-chain LCPFAC have shown that these...elimination decreases with increasing chain length. Elimination in humans...bioconcentration factor (BCF) values for C8 to C14 LCPFAC ranging...ADDRESSES. 1. USEPA. ``Long-Chain Perfluorinated Chemicals...

2012-08-15

7

Concentrations of perfluoroalkyl compounds in the serum and milk of lactating North Carolina women  

EPA Science Inventory

Perfluoroalkyl acids (PFAAs) and their derivatives are ubiquitous environmental contaminants that have been detected in a multitude of terrestrial and aquatic organisms. Some PFAAs bind the human estrogen receptors in vitro. Further, some PFAAs induce estrogen responsive genes a...

8

Perfluoroalkyl acids in the serum and milk of breastfeeding North Carolina women  

EPA Science Inventory

Perfluoroalkyl acids (PFAAs) comprise a group of man-made persistent environmental compounds. They are widely used in consumer products such as food packaging material, non-stick cookware and cleaning agents, and have been detected in drinking water. Certain PFAAs tend to bioaccu...

9

Temporal changes (1997-2012) of perfluoroalkyl acids and selected precursors (including isomers) in Swedish human serum.  

PubMed

Concentrations (including isomer patterns) and temporal changes (1997-2012) of perfluoroalkyl acids (PFAAs) and selected perfluorooctane sulfonate (PFOS) and perfluoroalkyl carboxylic acid (PFCA) precursors were determined in serum samples from Swedish women. Perfluorooctane sulfonamide (FOSA) and perfluorooctane sulfonamidoacetic acid (FOSAA), as well as its N-methyl and N-ethyl derivatives (MeFOSAA and EtFOSAA) were consistently detected. Highest PFOS precursor concentrations were found for EtFOSAA (before year 2000) or MeFOSAA and FOSAA (after 2000). Disappearance half-lives for all PFOS precursors were shorter compared to PFOS. 4:2/6:2 and 6:2/6:2 polyfluoroalkyl phosphate diesters (diPAPs) were detected in <60% of the samples, whereas 6:2/8:2 and 8:2/8:2 diPAPs were detected in >60% of the samples, but showed no significant change in concentrations over time. Linear and sum-branched isomers were quantified separately for three PFAAs and three precursors. Significant changes between 1997 and 2012 in the % linear isomer were observed for PFOA and FOSA (increase) and PFOS (decrease). PMID:25660070

Gebbink, Wouter A; Glynn, Anders; Berger, Urs

2015-04-01

10

Thyroid Function and Perfluoroalkyl Acids in Children Living Near a Chemical Plant  

PubMed Central

Background: Animal studies suggest that some perfluoroalkyl acids (PFAAs), including perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), and perfluorononanoic acid (PFNA) may impair thyroid function. Epidemiological findings, mostly related to adults, are inconsistent. Objectives: We investigated whether concentrations of PFAAs were associated with thyroid function among 10,725 children (1–17 years of age) living near a Teflon manufacturing facility in the Mid-Ohio Valley (USA). Methods: Serum levels of thyroid-stimulating hormone (TSH), total thyroxine (TT4), and PFAAs were measured during 2005–2006, and information on diagnosed thyroid disease was collected by questionnaire. Modeled in utero PFOA concentrations were based on historical information on PFOA releases, environmental distribution, pharmacokinetic modeling, and residential histories. We performed multivariate regression analyses. Results: Median concentrations of modeled in utero PFOA and measured serum PFOA, PFOS, and PFNA were 12, 29, 20, and 1.5 ng/mL, respectively. The odds ratio for hypothyroidism (n = 39) was 1.54 [95% confidence interval (CI): 1.00, 2.37] for an interquartile range (IQR) contrast of 13 to 68 ng/mL in serum PFOA measured in 2005–2006. However, an IQR shift in serum PFOA was not associated with TSH or TT4 levels in all children combined. IQR shifts in serum PFOS (15 to 28 ng/mL) and serum PFNA (1.2 to 2.0 ng/mL) were both associated with a 1.1% increase in TT4 in children 1–17 years old (95% CIs: 0.6, 1.5 and 0.7, 1.5 respectively). Conclusions: This is the first large-scale report in children suggesting associations of serum PFOS and PFNA with thyroid hormone levels and of serum PFOA and hypothyroidism. PMID:22453676

Mondal, Debapriya; Armstrong, Ben; Bloom, Michael S.; Fletcher, Tony

2012-01-01

11

Toxicology of Perfluoroalkyl Acids*  

EPA Science Inventory

The perfluoroalkyl acids (PFAAs) are a family of organic chemicals consisting of a perfluorinated carbon backbone (4-12 in length) and an acidic functional moiety (carboxylate or sulfonate). These compounds are chemically stable, have excellent surface-tension reducing properties...

12

A simple and rapid extraction method for sensitive determination of perfluoroalkyl substances in blood serum suitable for exposure evaluation.  

PubMed

In this work, we propose a microextraction method based on a new supramolecular solvent (SUPRAS) made up of reverse aggregates of hexanoic acid, combined with liquid chromatography/triple quadrupole mass spectrometry (LC/QQQ MS-MS) for the determination of the perfluoroalkyl substances (PFASs) in blood serum. A SUPRAS is a nano-structured liquid made up of surfactant aggregates synthesized through a self-assembly process. The method involved the acidification of 765 ?L of blood serum (600 ?mol of hydrochloric acid per mL of serum) followed by the addition of hexanoic acid (97 ?L) and tetrahydrofuran (THF) (600 ?L), conditions under which the supramolecular solvent (?360 ?L) formed in situ after vortex-shaking and centrifugation. Parameters affecting extraction efficiency and concentration factors were studied. The overall sample treatment took only 20 min and several samples (20-30) can be simultaneously analyzed using conventional lab equipments, making additional investments unnecessary. Recoveries for the internal standards in samples ranged from 75 to 89% with relative standard deviations between 1 and 15%. Calibration was based on the use of internal standards. The method was very sensitive with detection limits ranging from 2 to 20 pg mL(-1) for PFASs. The approach developed was successfully applied to the determination of PFASs in different blood serum samples. The concentration of PFASs found in samples of animal origin ranged between 17 and 197.3 pg mL(-1) and between 84 and 5168 pg mL(-1) in samples of human origin. Both the analytical and operational features of this method make it suitable for the evaluation of exposure to PFASs. PMID:22420956

Luque, Noelia; Ballesteros-Gómez, Ana; van Leeuwen, Stefan; Rubio, Soledad

2012-04-27

13

Effects of chemical oxidants on perfluoroalkyl acid transport in one-dimensional porous media columns.  

PubMed

In situ chemical oxidation (ISCO) is a remediation approach that is often used to remediate soil and groundwater contaminated with fuels and chlorinated solvents. At many aqueous film-forming foam-impacted sites, perfluoroalkyl acids (PFAAs) can also be present at concentrations warranting concern. Laboratory experiments were completed using flow-through one-dimensional columns to improve our understanding of how ISCO (i.e., activated persulfate, permanganate, or catalyzed hydrogen peroxide) could affect the fate and transport of PFAAs in saturated porous media. While the resultant data suggest that standard ISCO is not a viable remediation strategy for PFAA decomposition, substantial changes in PFAA transport were observed upon and following the application of ISCO. In general, activated persulfate decreased PFAA transport, while permanganate and catalyzed hydrogen peroxide increased PFAA transport. PFAA sorption increased in the presence of increased aqueous polyvalent cation concentrations or decreased pH. The changes in contaminant mobility were greater than what would be predicted on the basis of aqueous chemistry considerations alone, suggesting that the application of ISCO results in changes to the porous media matrix (e.g., soil organic matter quality) that also influence transport. The application of ISCO is likely to result in changes in PFAA transport, where the direction (increased or decreased transport) and magnitude are dependent on PFAA characteristics, oxidant characteristics, and site-specific factors. PMID:25621878

McKenzie, Erica R; Siegrist, Robert L; McCray, John E; Higgins, Christopher P

2015-02-01

14

Toxicology of Perfluoroalkyl acids  

EPA Science Inventory

The Perfluoroalkyl acids(PFAAs) area a family of organic chemicals consisting of a perflurinated carbon backbone (4-12in length) and a acidic functional moiety (Carboxylate or sulfonate). These compounds have excellent surface-tension reducing properties and have numerous industr...

15

Association of polyfluoroalkyl chemical exposure with serum lipids in children.  

PubMed

Perfluoroalkyl and polyfluoroalkyl substances (PFASs), as well as polymers of PFASs, have been widely used in commercial applications and have been detected in humans and the environment. Previous epidemiological studies have shown associations between particular PFAS chemicals and serum lipid concentrations in adults, particularly perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). There exists, however, limited information concerning the effect of PFASs have on serum lipids among children. In the present cross-sectional study, 225 Taiwanese children (12-15years of age) were recruited to determine the relationship between serum level PFASs and lipid concentration. Results showed that eight out of ten particular PFASs were detected in the serum of >94% of the participants. Serum PFOS and perfluorotetradecanoic acid (PFTA) levels were at an order of magnitude higher than the other PFASs, with arithmetical means of 32.4 and 30.7ng/ml in boys and 34.2 and 27.4ng/ml in girls, respectively. However, the variation in serum PFTA concentration was quite large. Following covariate adjustment, linear regression models revealed that PFOS, PFOA, and perfluorononanoic acid (PFNA) were positively associated with total cholesterol (TC), low-density lipoprotein (LDL) and triglycerides (TG), particularly for PFOS and PFTA. Quartile analysis, with the lowest exposure quartile as a reference, yielded associations between serum PFTA and elevations in TC (p=0.002) and LDL (p=0.004). Though not statistically significant, high-density lipoprotein (HDL) appeared to decrease linearly across quartiles for PFOS and PFOA exposure. In conclusion, a significant association was observed between serum PFASs and lipid level in Taiwanese children. These findings for PFTA are novel, and emphasize the need to investigate the exposure route and toxicological evidence of PFASs beyond PFOS and PFOA. PMID:25638651

Zeng, Xiao-Wen; Qian, Zhengmin; Emo, Brett; Vaughn, Michael; Bao, Jia; Qin, Xiao-Di; Zhu, Yu; Li, Jie; Lee, Yungling Leo; Dong, Guang-Hui

2015-04-15

16

Loss and in situ production of perfluoroalkyl chemicals in outdoor biosolids-soil mesocosms.  

PubMed

An outdoor mesocosm study was conducted in Baltimore, Maryland, to explore the fate of thirteen perfluoroalkyl substances (PFASs) over the course of three years in biosolids/soil mixtures (1:2) exposed to ambient outdoor conditions. Analysis by liquid chromatography tandem mass spectrometry showed perfluorooctanoate (PFOA) to be the most abundant analyte found early in the soil weathering experiment at 24.1 ng/g dry weight (dw), followed by perfluoroundecanoate (PFUnDA) and perfluorodecanoate (PFDA) at 18.4 and 17.4 ng/g dw, respectively. Short-chain perfluorinated carboxylates (PFCAs; C4-C8) showed observable loss from biosolids/soil mixtures, with experimentally determined first-order half-lives in soil ranging from 385 to 866 days. Perfluorooctane sulfonate (PFOS), perfluorononaoate (PFNA) and PFUnDA levels in biosolids/soil mixtures remained stable, while other long-chain PFCAs [PFDA, perfluorododecanoate (PFDoDA)] and perfluorooctane sulfonamide (PFOSA) levels increased over time, presumably due to the breakdown of unidentified precursors in a process analogous to that reported previously for wastewater treatment plants. This study informs risk assessment initiatives by furnishing data on the environmental persistence of PFASs while also constituting the first report on in situ production of long-chained PFASs in terrestrial environments. PMID:24834828

Venkatesan, Arjun K; Halden, Rolf U

2014-07-01

17

TOXICOGENOMIC STUDY OF TRIAZOLE FUNGICIDES AND PERFLUOROALKYL ACIDS IN RAT LIVERS ACCURATELY CATEGORIZES CHEMICALS AND IDENTIFIES MECHANISMS OF TOXICITY  

EPA Science Inventory

Toxicogenomic analysis of five environmental chemicals was performed to investigate the ability of genomics to predict toxicity, categorize chemicals, and elucidate mechanisms of toxicity. Three triazole antifungals (myclobutanil, propiconazole, and triadimefon) and two perfluori...

18

TOXICOGENOMIC DISSECTION OF RODENT LIVER TRANSCRIPT PROFILES AFTER EXPOSURE TO PERFLUOROALKYL ACIDS  

EPA Science Inventory

Exposure to peroxisome proliferator chemicals (PPC) leads to alterations in the balance between hepatocyte growth and apoptosis, increases in liver to body weight ratios and liver tumors. The perfluoroalkyl acids including perfluorooctanoate (PFOA) and perfluorooctane sulfonate (...

19

Prostate-Specific Antigen and Perfluoroalkyl Acids in the C8 Health Study Population  

PubMed Central

Purpose: To inform questions raised by inconsistent findings regarding an association between perfluoroalkyl acids (PFAAs) and prostate cancer by assessing the relationship of PFAAs in human serum to prostate-specific antigen (PSA). Materials and Methods: Using 2005 to 2006 survey data from a large survey population, we compared serum PFAA concentrations in adult males with PSA concentrations adjusted for risk factors including age, body mass index, smoking status, and socioeconomic status. Results: Perfluoroalkyl acids are not consistently associated with PSA concentration in general, or with PSA more than 4.0. Discussion: These findings do not provide evidence that PFAA exposure is associated with PSA. PMID:25563548

Zhang, Jianjun; Fan, Hongmin

2015-01-01

20

Aromatic and heterocyclic perfluoroalkyl sulfides. Methods of preparation  

PubMed Central

Summary This review covers all of the common methods for the syntheses of aromatic and heterocyclic perfluoroalkyl sulfides, a class of compounds which is finding increasing application as starting materials for the preparation of agrochemicals, pharmaceutical products and, more generally, fine chemicals. A systematic approach is taken depending on the mode of incorporation of the SRF groups and also on the type of reagents used. PMID:20978611

2010-01-01

21

Perfluoroalkyl polytriazines containing pendent iododifluoromethyl groups  

NASA Technical Reports Server (NTRS)

New perfluoroalkyl polytriazines containing pendent iododifluoromethyl groups are prepared by the reaction of perfluoroalkyl dinitriles with ammonia to form poly(imidoylamidines), followed by the cyclization of the imidoylamidine groups with, e.g., various mixtures of a perfluoroacyl fluoride with an omega iodoperfluoroacyl fluoride. The polytriazines obtained can be cured by heat which causes crosslinking at the iododifluoromethyl groups by elimination of iodine and formation of carbon-to-carbon bonds.

Rosser, R. W.; Psarras, T. (inventors)

1980-01-01

22

Perfluoroalkyl and Polyfluoroalkyl Substances in the Environment: Terminology, Classification, and Origins  

PubMed Central

The primary aim of this article is to provide an overview of perfluoroalkyl and polyfluoroalkyl substances (PFASs) detected in the environment, wildlife, and humans, and recommend clear, specific, and descriptive terminology, names, and acronyms for PFASs. The overarching objective is to unify and harmonize communication on PFASs by offering terminology for use by the global scientific, regulatory, and industrial communities. A particular emphasis is placed on long-chain perfluoroalkyl acids, substances related to the long-chain perfluoroalkyl acids, and substances intended as alternatives to the use of the long-chain perfluoroalkyl acids or their precursors. First, we define PFASs, classify them into various families, and recommend a pragmatic set of common names and acronyms for both the families and their individual members. Terminology related to fluorinated polymers is an important aspect of our classification. Second, we provide a brief description of the 2 main production processes, electrochemical fluorination and telomerization, used for introducing perfluoroalkyl moieties into organic compounds, and we specify the types of byproducts (isomers and homologues) likely to arise in these processes. Third, we show how the principal families of PFASs are interrelated as industrial, environmental, or metabolic precursors or transformation products of one another. We pay particular attention to those PFASs that have the potential to be converted, by abiotic or biotic environmental processes or by human metabolism, into long-chain perfluoroalkyl carboxylic or sulfonic acids, which are currently the focus of regulatory action. The Supplemental Data lists 42 families and subfamilies of PFASs and 268 selected individual compounds, providing recommended names and acronyms, and structural formulas, as well as Chemical Abstracts Service registry numbers. Integr Environ Assess Manag 2011;7:513–541. © 2011 SETAC PMID:21793199

Buck, Robert C; Franklin, James; Berger, Urs; Conder, Jason M; Cousins, Ian T; de Voogt, Pim; Jensen, Allan Astrup; Kannan, Kurunthachalam; Mabury, Scott A; van Leeuwen, Stefan PJ

2011-01-01

23

Isomer profiles of perfluoroalkyl substances in water and soil surrounding a chinese fluorochemical manufacturing park.  

PubMed

Despite that China is the largest global manufacturer of perfluoroalkyl substances (PFASs), the manufacturing methods and isomer purity of these chemicals are generally unknown. Here, sampling was conducted around a major fluorochemical manufacturing park in China in 2012, including soil and water collection inside the park, including from a wastewater treatment plant (WWTP), as well as in surrounding rivers and soil (?15 km radius). Perfluoroalkyl sulfonates (PFSAs) were lower than perfluoroalkyl carboxylates (PFCAs) in all samples, and short-chain (C4-C6) PFCAs were predominant. Perfluoroalkyl phosphonates and phosphate diesters were occasionally detected, but at low detection frequency. Branched isomers of perfluorobutanesulfonate (PFBS) are reported for the first time, accounting for 15-27% of total PFBS in water. An enrichment of isopropyl-PFOA (28%) was found in WWTP influent, suggesting its manufacturing primarily by isopropyl telomerization. More numerous branched isomers were observed for the longer C9-C13 PFCAs (e.g., C12 PFCA had 16 branched isomers), including high proportions of one major branched isomer (likely isopropyl), possibly as impurities from isopropyl-PFOA manufacturing. Overall, short-chain perfluorinated acids were the predominant PFASs being released, but PFOA was still a major chemical in use at this site, primarily from isopropyl telomerization. PMID:25798817

Jin, Hangbiao; Zhang, Yifeng; Zhu, Lingyan; Martin, Jonathan W

2015-04-21

24

Perfluoroalkylated compounds induce cell death and formation of reactive oxygen species in cultured cerebellar granule cells.  

PubMed

The present communication investigates the effects of different perfluoroalkylated compounds (PFCs) on formation of reactive oxygen species (ROS) and cell death in cultured cerebellar granule cells. This allows direct comparison with similar effects found for other environmental contaminants like polychlorinated biphenyls and brominated flame-retardants. The increase in ROS formation and cell death was assayed using the fluorescent probe 2,7-dichlorofluorescin diacetate (DCFH-DA) and the trypan blue exclusion assay. The effects of the PFCs were structure dependent. Cell death was induced at relatively low concentrations by perfluorooctyl sulfonate (PFOS), perfluorooctane sulfonylamide (PFOSA) and the fluorotelomer alcohol 1H, 1H, 2H, 2H-perfluorodecanol (FTOH 8:2) with EC(50)-values of 62 ± 7.6, 13 ± 1.8 and 15 ± 4.2 ?M (mean ± SD) respectively. PFOS, perfluorooctanoic acid (PFOA) and PFOSA induced a concentration dependent increase in ROS formation with EC(50)-values of 27 ± 9.0, 25 ± 11 and 57 ± 19?M respectively. Reduced cell viability and ROS formation were observed at concentration level close to what is found in serum of occupationally exposed workers. The effect of PFCs on ROS formation and cell viability was compared with other halogenated compounds and future investigations should emphasize effects of mixtures and how physical chemical properties of the compounds influence their toxicity. PMID:23340305

Reistad, Trine; Fonnum, Frode; Mariussen, Espen

2013-03-27

25

Environmental and Toxicity Effects of Perfluoroalkylated Substances  

Microsoft Academic Search

The production, use, environmental fate, occurrence, and toxicity of perfluoroalkylated substances have been reviewed. Although\\u000a only a limited number of essential physicochemical data are available, thus hampering a complete assessment of the environmental\\u000a fate of PFAS, it has become clear that PFAS behave differently from other nonpolar organic micropollutants. PFAS are present\\u000a in environmental media in urbanized areas both with

Floris M. Hekster; Remi W. P. M. Laane; Pim Voogt

2003-01-01

26

Chemical concentration measurement in blood serum and urine samples using liquid-core optical fiber Raman  

E-print Network

Chemical concentration measurement in blood serum and urine samples using liquid-core optical fiber Raman spectroscopy Dahu Qi and Andrew J. Berger We report measurements of chemical concentrations to increase the collected signal strength. Both Raman and absorption spectra were acquired in the near

Berger, Andrew J.

27

Perfluoroalkyl substances and thyroid function in older adults.  

PubMed

Current understanding of the thyroid disruptive properties of perfluoroalkyl substances (PFASs), particularly in aging populations, is limited. The objectives of this study were to (i) assess associations between thyroid function, as measured by serum thyrotropin (thyroid stimulating hormone, TSH), free thyroxine (fT4), total thyroxine (T4), and total triiodothyronine (T3), and serum perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in an aging population and (ii) determine if other persistent organic pollutants with thyroid disruptive properties including polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) modify such associations. We conducted a cross-sectional study of 87 men and women 55 to 74years of age, without clinically-diagnosed thyroid disease, who resided in upper Hudson River communities in New York. Geometric means (standard deviations) of serum PFOS and PFOA were 31.6 (1.7) ng/mL and 9.17 (1.72) ng/mL, respectively. Multivariable linear regression analyses indicated that one interquartile range difference in PFOS corresponded to 4% and 9% increases in fT4 and T4 respectively. We detected statistical interactions between PFOA and age for effects on fT4 and T4; joint increases in PFOA and age were associated with increases in fT4 and T4, of 3% and 7%, respectively. We also detected statistical interactions between PFOS and total PCBs for the effect on T3 and between PFOA and total PBDEs for the effect on TSH. Our results suggest that PFASs are associated with subtle alterations in thyroid hormone levels in this population, and that these associations are likely to vary by age, and levels of PCBs and PBDEs. PMID:25483837

Shrestha, Srishti; Bloom, Michael S; Yucel, Recai; Seegal, Richard F; Wu, Qian; Kannan, Kurunthachalam; Rej, Robert; Fitzgerald, Edward F

2015-02-01

28

Selected physicochemical aspects of poly- and perfluoroalkylated substances relevant to performance, environment and sustainability-Part one.  

PubMed

The elemental characteristics of the fluorine atom tell us that replacing an alkyl chain by a perfluoroalkyl or polyfluorinated chain in a molecule or polymer is consequential. A brief reminder about perfluoroalkyl chains, fluorocarbons and fluorosurfactants is provided. The outstanding, otherwise unattainable physicochemical properties and combinations thereof of poly and perfluoroalkyl substances (PFASs) are outlined, including extreme hydrophobic and lipophobic character; thermal and chemical stability in extreme conditions; remarkable aptitude to self-assemble into sturdy thin repellent protecting films; unique spreading, dispersing, emulsifying, anti-adhesive and levelling, dielectric, piezoelectric and optical properties, leading to numerous industrial and technical uses and consumer products. It was eventually discovered, however, that PFASs with seven or more carbon-long perfluoroalkyl chains had disseminated in air, water, soil and biota worldwide, are persistent in the environment and bioaccumulative in animals and humans, raising serious health and environmental concerns. Further use of long-chain PFASs is environmentally not sustainable. Most leading manufacturers have turned to shorter four to six carbon perfluoroalkyl chain products that are not considered bioaccumulative. However, many of the key performances of PFASs decrease sharply when fluorinated chains become shorter. Fluorosurfactants become less effective and less efficient, provide lesser barrier film stability, etc. On the other hand, they remain as persistent in the environment as their longer chain homologues. Surprisingly little data (with considerable discrepancies) is accessible on the physicochemical properties of the PFASs under examination, a situation that requires consideration and rectification. Such data are needed for understanding the environmental and in vivo behaviour of PFASs. They should help determine which, for which uses, and to what extent, PFASs are environmentally sustainable. PMID:25245564

Krafft, Marie Pierre; Riess, Jean G

2015-06-01

29

Serum-induced G0/G1 transition in chemically transformed 3T3 cells  

SciTech Connect

Quiescent, chemically transformed (benzo-a-pyrene) BALB/c 3T3 cells (BP A31) enter the cell division cycle when exposed to complete medium containing 10% fetal calf serum (FCS); the number of cells recruited is a function of the duration of serum exposure. The recruitment of cells by short (<4 h) serum pulses is not inhibited by simultaneous exposure to cycloheximide (CH), and therefore the initial commitment does not require protein synthesis. The cells enter S phase with a constant delay following the removal of CH, even if CH exposure has been continued for as long as 20 h after the end of the serum pulse. The cell recruitment by serum pulses was inhibited by 5,6-dichloro-1-..beta..-D-ribofuranosyl-benzimidazole (DRB), an inhibitor of cytoplasmic mRNA accumulation. These data suggest that serum exposure produces a stable memory that is necessary and sufficient for the eventual progression through G1 to S phase that occurs when protein synthesis is resumed after the removal of CH; this memory probably consists of mRNA species that are induced by serum and that are stable in the absence of protein synthesis. Unexpectedly, pretreatment of quiescent BP A31 cells with CH (8-24 h) dramatically increased the fraction of the total cell population that is recruited by a serum pulse of fixed duration.

Gray, H.E.; Buchou, T.; Mester, J.

1987-03-01

30

Developmental Toxicity of Perfluoroalkyl Acid Mixtures in CD-1 Mice  

EPA Science Inventory

Perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS) and perfluorononanoic acid (PFNA) belong to a family of fluoro-organic compounds known as perfluoroalkyl acids (PFAAs). PFAAs have been widely used in industrial and commercial applications, and have been found to be...

31

Phlebotomy Treatment for Elimination of Perfluoroalkyl Acids in a Highly Exposed Family: A Retrospective Case-Series  

PubMed Central

Background Perfluoroalkyl acids (PFAAs) are a family of commonly used synthetic chemicals that have become widespread environmental contaminants. In human serum, perfluorohexane sulfonate (PFHxS), perflurooctane sulfonate (PFOS), and perfluorooctanoate (PFOA) are most frequently detected, in part owing to their long elimination half-lives of between 3.8 yrs (PFOA) and 8.5 yrs (PFHxS). These PFAAs also cross the placenta and have been associated with developmental toxicity, and some are considered likely human carcinogens. Interventions to eliminate PFAAs in highly contaminated individuals would reduce future health risks, but minimal research has been conducted on methods to facilitate accelerated human clearance of these persistent substances. Methods Six patients with elevated serum concentrations from a single family were treated by intermittent phlebotomy over a 4–5 year period at intervals similar to, or less frequent than what is done for routine blood donation at Canadian Blood Services. The apparent elimination half-life (HLapp) for PFHxS, PFOS, and PFOA in this treated population was calculated in each patient and compared to the intrinsic elimination half-lives (HLin) from a literature reference population of untreated fluorochemical manufacturing plant retirees (n?=?26, age >55 yrs). Results For all three PFAAs monitored during phlebotomy, HLapp in each of the family members (except the mother, who had a low rate of venesection) was significantly shorter than the geometric mean HL measured in the reference population, and in some cases were even shorter compared to the fastest eliminator in the reference population. Conclusion This study suggests significantly accelerated PFAA clearance with regular phlebotomy treatment, but the small sample size and the lack of controls in this clinical intervention precludes drawing firm conclusions. Given the minimal risks of intermittent phlebotomy, this may be an effective and safe clinical intervention to diminish the body burden of PFAAs in highly exposed people. PMID:25504057

Genuis, Stephen J.; Liu, Yanna; Genuis, Quentin I. T.; Martin, Jonathan W.

2014-01-01

32

Mass Balance of Perfluoroalkyl Acids in the Baltic Sea  

PubMed Central

A mass balance was assembled for perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorodecanoic acid (PFDA), and perfluorooctanesulfonic acid (PFOS) in the Baltic Sea. Inputs (from riverine discharge, atmospheric deposition, coastal wastewater discharges, and the North Sea) and outputs (to sediment burial, transformation of the chemical, and the North Sea), as well as the inventory in the Baltic Sea, were estimated from recently published monitoring data. Formation of the chemicals in the water column from precursors was not considered. River inflow and atmospheric deposition were the dominant inputs, while wastewater treatment plant (WWTP) effluents made a minor contribution (<5%). A mass balance of the Oder River watershed was assembled to explore the sources of the perfluoroalkyl acids (PFAAs) in the river inflow. It indicated that WWTP effluents made only a moderate contribution to riverine discharge (21% for PFOA, 6% for PFOS), while atmospheric deposition to the watershed was 1–2 orders of magnitude greater than WWTP discharges. The input to the Baltic Sea exceeded the output for all four PFAAs, suggesting that inputs were higher during 2005–2010 than during the previous 20 years despite efforts to reduce emissions of PFAAs. One possible explanation is the retention and delayed release of PFAAs from atmospheric deposition in the soils and groundwater of the watershed. PMID:23528236

2013-01-01

33

Perfluoroalkylated substances (PFAS) affect oxidative stress biomarkers in vitro.  

PubMed

Perfluoroalkylated substances (PFAS) have been widely used since 1950s and humans are exposed through food, drinking water, consumer products, dust, etc. The long-chained PFAS are persistent in the environment and accumulate in wildlife and humans. They are suspected carcinogens and a potential mode of action is through generation of oxidative stress. Seven long-chained PFAS found in human serum were investigated for the potential to generate reactive oxygen species (ROS), induce DNA damage and disturb the total antioxidant capacity (TAC). The tested PFAS were perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonic acid (PFOS), perfluoroctanoic acid (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnA), and perfluorododecanoate (PFDoA). Using the human hepatoma cell line (HepG2) and an exposure time of 24h we found that all three endpoints were affected by one or more of the compounds. PFHxS, PFOA, PFOS and PFNA showed a dose dependent increase in DNA damage in the concentration range from 2×10(-7) to 2×10(-5)M determined by the comet assay. Except for PFDoA, all the other PFAS increased ROS generation significantly. For PFHxS and PFUnA the observed ROS increases were dose-dependent. Cells exposed to PFOA were found to have a significant lower TAC compared with the solvent control, whereas a non-significant trend in TAC decrease was observed for PFOS and PFDoA and an increase tendency for PFHxS, PFNA and PFUnA. Our results indicate a possible genotoxic and cytotoxic potential of the PFAS in human liver cells. PMID:25455676

Wielsře, Maria; Long, Manhai; Ghisari, Mandana; Bonefeld-Jřrgensen, Eva C

2015-06-01

34

Occurrence and sources of perfluoroalkyl acids in Italian river basins.  

PubMed

This paper presents a survey on the occurrence and sources of 11 perfluoroalkyl acids (PFAA) in the main river basins in Italy, covering about 40% of the Italian surface area and 45% of the Italian population. Total concentrations of PFAA ranged fromchemical plants which produce fluorinated polymers and intermediates, sited in the basin of rivers Po and Brenta, respectively, whose overall emission represents 57% of the total estimated PFAA load. Both rivers flow into the Adriatic Sea, raising concern for the marine ecosystem also because a significant PFOS load (0.3ty(-1)) is still present. Among the remaining activities, tanneries and textile industries are relevant sources of respectively PFBS and PFOA, together with short chain PFCA. As an example, the total PFAA load (0.12ty(-1)) from the textile district of Prato is equivalent to the estimated domestic emission of the whole population in all the studied basins. PMID:25108894

Valsecchi, Sara; Rusconi, Marianna; Mazzoni, Michela; Viviano, Gaetano; Pagnotta, Romano; Zaghi, Carlo; Serrini, Giuliana; Polesello, Stefano

2015-06-01

35

Promotion of Hepatocarcinogenesis by Perfluoroalkyl Acids in Rainbow Trout  

PubMed Central

Previously, we reported that perfluorooctanoic acid (PFOA) promotes liver cancer in a manner similar to that of 17?-estradiol (E2) in rainbow trout. Also, other perfluoroalkyl acids (PFAAs) are weakly estrogenic in trout and bind the trout liver estrogen receptor. The primary objective of this study was to determine whether multiple PFAAs enhance hepatic tumorigenesis in trout, an animal model that represents human insensitivity to peroxisome proliferation. A two-stage chemical carcinogenesis model was employed in trout to evaluate PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorooctane sulfonate (PFOS), and 8:2 fluorotelomer alcohol (8:2FtOH) as complete carcinogens or promoters of aflatoxin B1 (AFB1)- and/or N-methyl-N?-nitro-N-nitrosoguanidine (MNNG)-induced liver cancer. A custom trout DNA microarray was used to assess hepatic transcriptional response to these dietary treatments in comparison with E2 and the classic peroxisome proliferator, clofibrate (CLOF). Incidence, multiplicity, and size of liver tumors in trout fed diets containing E2, PFOA, PFNA, and PFDA were significantly higher compared with AFB1-initiated animals fed control diet, whereas PFOS caused a minor increase in liver tumor incidence. E2 and PFOA also enhanced MNNG-initiated hepatocarcinogenesis. Pearson correlation analyses, unsupervised hierarchical clustering, and principal components analyses showed that the hepatic gene expression profiles for E2 and PFOA, PFNA, PFDA, and PFOS were overall highly similar, though distinct patterns of gene expression were evident for each treatment, particularly for PFNA. Overall, these data suggest that multiple PFAAs can promote liver cancer and that the mechanism of promotion may be similar to that of E2. PMID:21984479

Benninghoff, Abby D.; Orner, Gayle A.; Buchner, Clarissa H.; Hendricks, Jerry D.; Duffy, Aaron M.; Williams, David E.

2012-01-01

36

Parameters affecting the formation of perfluoroalkyl acids during wastewater treatment.  

PubMed

This study examined the fate and behaviour of perfluoroalkyl acids (PFAAs) in liquid and solid samples from five different wastewater treatment types: facultative and aerated lagoons, chemically assisted primary treatment, secondary aerobic biological treatment, and advanced biological nutrient removal treatment. To the best of our knowledge, this is the largest data set from a single study available in the literature to date for PFAAs monitoring study in wastewater treatment. Perfluorooctanoic acid (PFOA) was the predominant PFAA in wastewater with levels from 2.2 to 150ng/L (influent) and 1.9 to 140ng/L (effluent). Perfluorooctanesulfonic acid (PFOS) was the predominant compound in primary sludge, waste biological sludge, and treated biosolids with concentrations from 6.4 to 2900ng/g dry weight (dw), 9.7 to 8200ng/gdw, and 2.1 to 17,000ng/gdw, respectively. PFAAs were formed during wastewater treatment and it was dependant on both process temperature and treatment type; with higher rates of formation in biological wastewater treatment plants (WWTPs) operating at longer hydraulic retention times and higher temperatures. PFAA removal by sorption was influenced by different sorption tendencies; median log values of the solid-liquid distribution coefficient estimated from wastewater biological sludge and final effluent were: PFOS (3.73)>PFDA (3.68)>PFNA (3.25)>PFOA (2.49)>PFHxA (1.93). Mass balances confirmed the formation of PFAAs, low PFAA removal by sorption, and high PFAA levels in effluents. PMID:24691135

Guerra, P; Kim, M; Kinsman, L; Ng, T; Alaee, M; Smyth, S A

2014-05-15

37

Serum levels of TCDD and dioxin-like chemicals in Rhesus monkeys chronically exposed to dioxin: correlation of increased serum PCB levels with endometriosis.  

PubMed

Humans and animals are exposed daily to a complex mixture of polyhalogenated aromatic hydrocarbons (PHAHs). Previous work has shown that exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is associated with a dose-dependent increase in the incidence and severity of endometriosis in the rhesus monkey. Dioxin-like chemicals can also exert effects in combination with TCDD via the aryl hydrocarbon receptor. This study demonstrates that the serum levels of TCDD and specific dioxin-like PHAH congeners were increased in TCDD-treated animals with endometriosis 13 years after the TCDD exposure. Nine TCDD-exposed and 6 unexposed female rhesus monkeys were evaluated for serum content of relevant compounds and for endometriosis by surgical laparoscopy. Additional studies were done on 4 animals that died 7 to 11 years after exposure to TCDD and 4 lead-treated animals with no history of PHAH treatment. For TCDD-exposed and unexposed animals, TCDD exposure correlated with an increased serum TCDD concentration. Furthermore, TCDD exposure and an elevated serum TCDD concentration were associated with increased serum levels of triglycerides, 1,2,3,6,7,8-hexachlorodibenzofuran, 3,3',4,4'-tetrachlorobiphenyl (TCB) and 3,3'4,4',5-pentachlorobiphenyl (PnCB). Importantly, the animals with elevated serum levels of 3,3',4,4'-TCB, 3,3',4,4',5-PnCB and an increased total serum TEQ had a high prevalence of endometriosis, and the severity of disease correlated with the serum concentration of 3,3,',4,4'-TCB. Increased serum concentrations of coplanar PCBs were also present in lead-treated animals. Implications of these findings for human health and the prevalence of endometriosis in humans will be discussed. PMID:11134554

Rier, S E; Turner, W E; Martin, D C; Morris, R; Lucier, G W; Clark, G C

2001-01-01

38

Environmental-Fate Patterns for Perfluoroalkylates and their Precursors  

EPA Science Inventory

Two sites with elevated concentrations of perfluoroalkylates (PFAs) and fluorotelomer alcohols (FTOHs) were studied: 1) agricultural fields near Decatur, AL on which sewage sludge had been applied; and 2) the Conasauga River system near Dalton, GA where treated sewage effluent is...

39

Perfluoroalkyl acids in Lake Superior water: Trends and sources  

Microsoft Academic Search

Perfluoroalkyl acids (PFAs) are a family of highly persistent compounds which are present in the environment as a result of degradation of polyfluorinated precursors, from use as processing aids for production of fluoropolymers, and use in fire fighting foams. The purpose of this study was to investigate prevailing concentrations and possible sources of PFAs in Lake Superior, as well as

Brian F. Scott; Amila O. De Silva; Christine Spencer; Emma Lopez; Sean M. Backus; Derek C. G. Muir

2010-01-01

40

78 FR 62443 - Perfluoroalkyl Sulfonates and Long-Chain Perfluoroalkyl Carboxylate Chemical Substances; Final...  

Federal Register 2010, 2011, 2012, 2013, 2014

...i) through (b)(1)(v) of this final rule that is intentionally used during fluoropolymer formulation, such as an emulsion stabilizer in aqueous dispersions, is subject to reporting for the significant new uses described in 40...

2013-10-22

41

Synthesis of the diazonium (perfluoroalkyl) benzenesulfonimide monomer from Nafion monomer for proton exchange membrane fuel cells  

NASA Astrophysics Data System (ADS)

One diazonium (perfluoroalkyl) benzenesulfonimide monomer, perfluoro-3, 6-dioxa-4-methyl-7-octene benzenesulfonyl imide, has been synthesized from Nafion monomer for the first time. With trifluorovinyl ether and diazonium precursors, the partially-fluorinated diazonium PFSI monomer can be polymerized and will provide chemically bonding with carbon electrode in proton exchange membrane fuel cells. A systematic study of the synthesis and characterization of this diazonium PFSI monomer has been conducted by varying reaction conditions. The optimized synthesis method has been established in the lab.

Mei, Hua; D'Andrea, Dan; Nguyen, Tuyet-Trinh; Nworie, Chima

2014-02-01

42

Migration of perfluoroalkyl acids from food packaging to food simulants.  

PubMed

A broad range of fluorochemicals is used to impart oil and water barrier properties to paper and paperboard food packaging. Many of the fluorochemicals are applied to paper and paperboard as complex mixtures containing reaction products and by-products and unreacted starting materials. This work primarily focussed on the determination of seven perfluorocarboxylic acids (PFCAs) in two commercially available food contact papers: a di-perfluoro-alkyloxy-amino-acid and a perfluoroalkyl phosphate surfactant. In addition, the migration of the PFCAs into five food simulants from two commercial packages was evaluated. All seven PFCAs were detected in the range of 700-2220 µg kg?ą of paper, while three perfluoroalkyl sulphonates were under the LOD. Results from migration tests showed that migration depends on paper characteristics, time and food simulant. The percentage of migration after 10 days at 40°C ranged from 4.8% to 100% for the two papers and different food simulants. PMID:23701306

Xu, Y; Noonan, G O; Begley, T H

2013-01-01

43

Perfluoroalkylated substances in the global tropical and subtropical surface oceans.  

PubMed

In this study, perfluoroalkylated substances (PFASs) were analyzed in 92 surface seawater samples taken during the Malaspina 2010 expedition which covered all the tropical and subtropical Atlantic, Pacific and Indian oceans. Nine ionic PFASs including C6-C10 perfluoroalkyl carboxylic acids (PFCAs), C4 and C6-C8 perfluoroalkyl sulfonic acids (PFSAs) and two neutral precursors perfluoroalkyl sulfonamides (PFASAs), were identified and quantified. The Atlantic Ocean presented the broader range in concentrations of total PFASs (131-10900 pg/L, median 645 pg/L, n = 45) compared to the other oceanic basins, probably due to a better spatial coverage. Total concentrations in the Pacific ranged from 344 to 2500 pg/L (median = 527 pg/L, n = 27) and in the Indian Ocean from 176 to 1976 pg/L (median = 329, n = 18). Perfluorooctanesulfonic acid (PFOS) was the most abundant compound, accounting for 33% of the total PFASs globally, followed by perfluorodecanoic acid (PFDA, 22%) and perfluorohexanoic acid (PFHxA, 12%), being the rest of the individual congeners under 10% of total PFASs, even for perfluorooctane carboxylic acid (PFOA, 6%). PFASAs accounted for less than 1% of the total PFASs concentration. This study reports the ubiquitous occurrence of PFCAs, PFSAs, and PFASAs in the global ocean, being the first attempt, to our knowledge, to show a comprehensive assessment in surface water samples collected in a single oceanic expedition covering tropical and subtropical oceans. The potential factors affecting their distribution patterns were assessed including the distance to coastal regions, oceanic subtropical gyres, currents and biogeochemical processes. Field evidence of biogeochemical controls on the occurrence of PFASs was tentatively assessed considering environmental variables (solar radiation, temperature, chlorophyll a concentrations among others), and these showed significant correlations with some PFASs, but explaining small to moderate percentages of variability. This suggests that a number of physical and biogeochemical processes collectively drive the oceanic occurrence and fate of PFASs in a complex manner. PMID:25325411

González-Gaya, Belén; Dachs, Jordi; Roscales, Jose L; Caballero, Gemma; Jiménez, Begońa

2014-11-18

44

DEVELOPMENT OF AN EPA METHOD FOR PERFLUOROALKYL COMPOUNDS IN DRINKING WATER  

EPA Science Inventory

Over the past five years, perfluoroalkyl compounds (PFCs) in water have become an emerging environmental issue. This research focuses on the development of an analytical method for the determination of perfluoroalkyl compounds in drinking water to be used by EPA's Office of Grou...

45

Assessment of serum biomarkers in rats after exposure to pesticides of different chemical classes.  

PubMed

There is increasing emphasis on the use of biomarkers of adverse outcomes in safety assessment and translational research. We evaluated serum biomarkers and targeted metabolite profiles after exposure to pesticides (permethrin, deltamethrin, imidacloprid, carbaryl, triadimefon, fipronil) with different neurotoxic actions. Adult male Long-Evans rats were evaluated after single exposure to vehicle or one of two doses of each pesticide at the time of peak effect. The doses were selected to produce similar magnitude of behavioral effects across chemicals. Serum or plasma was analyzed using commercial cytokine/protein panels and targeted metabolomics. Additional studies of fipronil used lower doses (lacking behavioral effects), singly or for 14 days, and included additional markers of exposure and biological activity. Biomarker profiles varied in the number of altered analytes and patterns of change across pesticide classes, and discriminant analysis could separate treatment groups from control. Low doses of fipronil produced greater effects when given for 14 days compared to a single dose. Changes in thyroid hormones and relative amounts of fipronil and its sulfone metabolite also differed between the dosing regimens. Most cytokine changes reflected alterations in inflammatory responses, hormone levels, and products of phospholipid, fatty acid, and amino acid metabolism. These findings demonstrate distinct blood-based analyte profiles across pesticide classes, dose levels, and exposure duration. These results show promise for detailed analyses of these biomarkers and their linkages to biological pathways. PMID:25497286

Moser, Virginia C; Stewart, Nicholas; Freeborn, Danielle L; Crooks, James; MacMillan, Denise K; Hedge, Joan M; Wood, Charles E; McMahen, Rebecca L; Strynar, Mark J; Herr, David W

2015-01-15

46

Evidence of remediation-induced alteration of subsurface poly- and perfluoroalkyl substance distribution at a former firefighter training area.  

PubMed

Poly- and perfluoroalkyl substances (PFASs) are a class of fluorinated chemicals that are utilized in firefighting and have been reported in groundwater and soil at several firefighter training areas. In this study, soil and groundwater samples were collected from across a former firefighter training area to examine the extent to which remedial activities have altered the composition and spatial distribution of PFASs in the subsurface. Log Koc values for perfluoroalkyl acids (PFAAs), estimated from analysis of paired samples of groundwater and aquifer solids, indicated that solid/water partitioning was not entirely consistent with predictions based on laboratory studies. Differential PFAA transport was not strongly evident in the subsurface, likely due to remediation-induced conditions. When compared to the surface soil spatial distributions, the relative concentrations of perfluorooctanesulfonate (PFOS) and PFAA precursors in groundwater strongly suggest that remedial activities altered the subsurface PFAS distribution, presumably through significant pumping of groundwater and transformation of precursors to PFAAs. Additional evidence for transformation of PFAA precursors during remediation included elevated ratios of perfluorohexanesulfonate (PFHxS) to PFOS in groundwater near oxygen sparging wells. PMID:24866261

McGuire, Meghan E; Schaefer, Charles; Richards, Trenton; Backe, Will J; Field, Jennifer A; Houtz, Erika; Sedlak, David L; Guelfo, Jennifer L; Wunsch, Assaf; Higgins, Christopher P

2014-06-17

47

Quantification of pharmaceuticals, personal care products, and perfluoroalkyl substances in the marine sediments of Puget Sound, Washington, USA.  

PubMed

Concentrations of 119 pharmaceuticals and personal care products (PPCPs) and 13 perfluoroalkyl substances (PFASs) in marine sediments measured throughout Puget Sound (n?=?10) and Bellingham Bay (n?=?30), Washington, USA, are reported. These data are among the first measurements of PPCPs and PFASs in marine sediments from the Pacific Northwest and provide a comparison to previous measurements of these chemicals in influent, effluent, and biosolids from municipal wastewater treatment plants throughout the region. The concentrations of both PPCPs and PFASs in sediments from Puget Sound and Bellingham Bay ranged from very low to non-detectable for most compounds. Only 14 of the 119 PPCPs and 3 of 13 PFASs were quantifiable in sediments. Diphenhydramine (an antihistamine) was most frequently detected (87.5% of samples), with a maximum concentration of 4.81?ng/g dry weight and an estimated mean detected concentration of 1.68?ng/g. Triclocarban (an antibacterial) was detected in 35.0% of the samples, with a maximum concentration of 16.6?ng/g dry weight. Perfluoroalkyl substances were detected in 2.5% of analyses. Perfluorobutanoate, perfluorooctane sulfonate, and perfluorooctane sulfonamide were detected in 7, 5, and 1 sample(s) each, respectively, with the highest concentrations observed for perfluorooctane sulfonate (1.5?ng/g). Detected concentrations were often highest within the industrial harbor in Bellingham Bay and near the cities of Seattle and Bremerton. Environ Toxicol Chem 2013;32:1701-1710. © 2013 SETAC. PMID:23843318

Long, Edward R; Dutch, Margaret; Weakland, Sandra; Chandramouli, Bharat; Benskin, Jonathan P

2013-08-01

48

Elevated levels of perfluoroalkyl acids in family members of occupationally exposed workers: the importance of dust transfer.  

PubMed

The exposure pathways of perfluoroalkyl acids (PFAAs) to humans are still not clear because of the complex living environment, and few studies have simultaneously investigated the bioaccumulative behaviour of different PFAAs in humans. In this study, serum, dust, duplicate diet, and other matrices were collected around a manufacturing plant in China, and homologous series of PFAAs were analysed. PFAA levels in dust and serum of local residents in this area were considerably higher than those in non-polluted area. Although dietary intake was the major exposure pathway in the present study, dust ingestion played an important role in this case. Serum PFAAs in local residents was significantly correlated with dust PFAAs levels in their living or working microenvironment. Serum PFAAs and dust PFAAs were significantly higher in family members of occupational workers (FM) than in ordinary residents (OR) (p < 0.01). After a careful analysis of the PFAAs exposure pathway, a potential pathway in addition to direct dust ingestion was suggested: PFAAs might transferred from occupational worker's clothes to dinners via cooking processes. The bioaccumulative potential of PFHxS and PFOS were higher than other PFAAs, which suggested a substantial difference between the bioaccumulative ability of perfluorinated sulfonic acids and perfluorinated carboxylic acids. PMID:25791573

Fu, Jianjie; Gao, Yan; Wang, Thanh; Liang, Yong; Zhang, Aiqian; Wang, Yawei; Jiang, Guibin

2015-01-01

49

Firefighters' exposure to perfluoroalkyl acids and 2-butoxyethanol present in firefighting foams.  

PubMed

The aim of this study was to assess eight firefighters' exposure to Sthamex 3% AFFF (aqueous film forming foam) in the simulation of aircraft accidents at Oulu airport in Finland. Study was conducted in 2010 before limitation for the use of PFOA and PFOS in AFFFs. Due to prospective limitation also eight commercially available AFFFs were evaluated from occupational and environmental point of view to find substitutive AFFFs for future. The firefighters' exposure to twelve perfluoroalkyl acids (PFAS) was analyzed in order to observe the signs of accumulation during three consecutive training sessions. The firefighters' short-term exposure to 2-butoxyethanol (EGBE) was analyzed by urinalysis of 2-butoxyacetic acid (2-BAA). For the background information also the concentration of PFAS in used AFFF-liquid was analyzed. Fire fighters' serum PFHxS and PFNA concentrations seemed to increase during the three training sessions although they were not the main PFAS in used AFFF. The statistical significance for the elevations was not able to test due to limited size of test group. In two training sessions, the average urinary excretions of 2-BAA exceeded the reference limit of the occupationally unexposed population. In the evaluations of the firefighting foams, non-fluorine based products were favored and the alcohol resistance properties of foams were recommended for consideration due to the increasing use of biofuels. PMID:25447453

Laitinen, Juha Ari; Koponen, Jani; Koikkalainen, Janne; Kiviranta, Hannu

2014-12-01

50

Exposure to perfluoroalkyl substances and sperm DNA global methylation in Arctic and European populations.  

PubMed

Perfluoroalkyl substances (PFASs) are widely used in a variety of industrial processes and products, and have been detected globally in humans and wildlife. PFASs are suspected to interfere with endocrine signaling and to adversely affect human reproductive health. The aim of the present study was to investigate the associations between exposure to PFASs and sperm global methylation levels in a population of non-occupationally exposed fertile men. Measurements of PFASs in serum from 262 partners of pregnant women from Greenland, Poland and Ukraine, were also carried out by liquid chromatography tandem mass spectrometry. Perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), and perfluorononanoic acid (PFNA) were detected in 97% of the blood samples. Two surrogate markers were used to assess DNA global methylation levels in semen samples from the same men: (a) average DNA methylation level in repetitive DNA sequences (Alu, LINE-1, Sat?) quantified by PCR-pyrosequencing after bisulfite conversion; (b) flow cytometric immunodetection of 5-methyl-cytosines. After multivariate linear regression analysis, no major consistent associations between PFASs exposure and sperm DNA global methylation endpoints could be detected. However, since weak but statistically significant associations of different PFASs with DNA hypo- and hyper-methylation were found in some of the studied populations, effects of PFASs on sperm epigenetic processes cannot be completely excluded, and this issue warrants further investigation. PMID:24889506

Leter, Giorgio; Consales, Claudia; Eleuteri, Patrizia; Uccelli, Raffaella; Specht, Ina O; Toft, Gunnar; Moccia, Tania; Budillon, Alfredo; Jönsson, Bo A G; Lindh, Christian H; Giwercman, Aleksander; Pedersen, Henning S; Ludwicki, Jan K; Zviezdai, Valentyna; Heederik, Dick; Bonde, Jens Peter E; Spanň, Marcello

2014-08-01

51

Estrogenic Activity of Perfluoroalkyl Acids in Juvenile Rainbow Trout (Oncorhynchus Mykiss)  

EPA Science Inventory

The potential estrogenic activity of perfluoroalkyl acids (PFAAs) was determined using separate screening and dose response studies with juvenile rainbow trout (Oncorhynchus mykiss). Results of this study indicate that some PFAAs may act as estrogens in fish....

52

Case-control study of multiple chemical sensitivity, comparing haematology, biochemistry, vitamins and serum volatile organic compound measures  

Microsoft Academic Search

Background Multiple chemical sensitivity (MCS), although poorly understood, is associated with considerable morbidity. Aim To investigate potential biological mechanisms underlying MCS in a case-control study. Methods Two hundred and twenty-three MCS cases and 194 controls (urban females, aged 30-64 years) fulfilled reproducible eligibility criteria with discriminant validity. Routine laboratory results and serum levels of volatile organic compounds (VOCs) were compared.

Cornelia Johanna Baines; Gail Elizabeth; Nicole Riley; David Edward; C. Cole; Lynn Marshall; Barry Loescher; Vartouhi Jazmaji

53

Locomotor behavior in zebrafish (Danio rerio) larvae exposed to perfluoroalkyl acids.  

PubMed

Perfluoroalkyl acids (PFAAs) are persistent organic contaminants that have been detected in wildlife, humans and the environment. Studies have shown that the toxicity of PFAAs is determined by the carbon chain length as well as the attached functional group. The locomotor activity of zebrafish larvae has become widely used for evaluation of chemicals with neurotoxic properties. In the present study the behavioral effects of seven structurally different PFAAs (i.e. TFAA, PFBA, PFOA, PFNA, PFDA, PFBS and PFOS) were evaluated in zebrafish larvae. Exposure to high concentrations of TFAA, PFNA, PFBS and PFOS resulted in distinct changes in behavioral patterns. Based on redundancy analysis, our results demonstrate three main factors affecting zebrafish larval locomotor behavior. The strongest effect on behavior was determined by the carbon chain length and the attached functional group. PFAAs with longer carbon chain length as well as PFAAs with attached sulfonic groups showed larger potential to affect locomotor behavior in zebrafish larvae. Also the concentration of the PFAAs determined the behavior responses. The results of the present study are in agreement with previous studies showing correlations between the chemical structure of PFAAs and the toxicological effects. PMID:24215719

Ulhaq, Mazhar; Orn, Stefan; Carlsson, Gunnar; Morrison, David A; Norrgren, Leif

2013-11-15

54

Perfluoroalkyl contaminants in a food web from Lake Ontario.  

PubMed

Perfluorooctane sulfonate (PFOS) is a persistent and bioaccumulative perfluorinated acid detectable in humans and wildlife worldwide that has alerted scientists to examine the environmental fate of other fluorinated organic contaminants. Recently a homologous series of perfluoroalkyl carboxylates (PFCAs) was detected in the Arctic, yet little is known about their sources, breadth of contamination, or environmental distribution. In this study we analyzed for PFOS, the homologous series of PFCAs ranging from 8 to 15 carbons in chain length, and the PFOS-precursor heptadecafluorooctane sulfonamide (FOSA) in various organisms from a food web of Lake Ontario. The sampled organisms included a top predator fish, lake trout (Salvelinus namaycush), three forage fish species including rainbow smelt (Osmerus mordax), slimy sculpin (Cottus cognatus), and alewife (Alosa pseudoharengus), and two invertebrates Diporeia (Diporeia hoyi) and Mysis (Mysis relicta). A striking finding was that the highest mean concentration for each fluorinated contaminantwas detected in the benthic macroinvertebrate Diporeia, which occupies the lowest trophic level of all organisms analyzed. Perfluorinated acid concentrations in Diporeia were often 10-fold higher than in Mysis, a predominantly pelagic feeder, suggesting that a major source of perfluoroalkyl contaminants to this food web was the sediment, not the water. PFOS was the dominant acid in all samples, but long-chain PFCAs, ranging in length from 8 to 15 carbons, were also detected in most samples between <0.5 and 90 ng/ g. Among Mysis and the more pelagic fish species (e.g. excluding Diporeia and sculpin) there was evidence for biomagnification, but the influence of foraging on highly contaminated Diporeia and sculpin by these fish may have overestimated trophic magnification factors (TMFs), which ranged from 0.51 for FOSA to 5.88 for PFOS. By accounting for the known diet composition of lake trout, it was shown that bioaccumulation was indeed occurring at the top of the food web for all perfluoroalkyl compounds except PFOA. Future monitoring at other locations in Lake Ontario, and in other aquatic environments, is necessary to determine if these food web dynamics are widespread. Archived lake trout samples collected between 1980 and 2001 showed that mean whole body PFOS concentrations increased from 43 to 180 ng/g over this period, but not linearly, and may have been indirectly influenced by the invasion and proliferation of zebra mussels (Dreissena polymorpha) through effects on the population and ecology of forage fishes. PMID:15543740

Martin, Jonathan W; Whittle, D Michael; Muir, Derek C G; Mabury, Scott A

2004-10-15

55

Cotton fabric modification for imparting high water and oil repellency using perfluoroalkyl phosphate acrylate via ?-ray-induced grafting  

NASA Astrophysics Data System (ADS)

The perfluoroalkyl phosphate acrylates were grafted onto a cotton fabric via ?-ray irradiation to improve the hydrophobic and oleophobic properties. The change in chemical structure of grafted cotton fabric was detected by the Fourier transform infrared spectroscopy and the X-ray photoelectron spectroscopy. The contact angles for water and sunflower oil were determined to be over 150° and 140°, respectively, after irradiated with a dose range of 471-5664 Gy. The flame retardancy of the fabric with a grafting ratio of over 13.0 wt% was improved, reaching to 24 compared with 18 of which before grafted, according to the limiting oxygen index measurement. The microstructure of the fabric before and after grafted was observed by the scanning electron microscope.

Miao, Hui; Bao, Fenfen; Cheng, Liangliang; Shi, Wenfang

2010-07-01

56

Are levels of perfluoroalkyl substances in soil related to urbanization in rapidly developing coastal areas in North China?  

PubMed

Concentrations of 13 perfluoroalkyl substances (PFASs) were quantified in 79 surface soil samples from 17 coastal cities in three provinces and one municipality along the Bohai and Yellow Seas. The ?PFASs concentrations ranged from less than limitation of quantification (LOQ) to 13.97 ng/g dry weight (dw), with a mean of 0.98 ng/g dw. The highest concentration was observed along the Xiaoqing River from Shandong province, followed by that from the Haihe River in Tianjin (10.62 ng/g dw). Among four regions, ?PFASs concentrations decreased in the order of Tianjin, Shandong, Liaoning and Hebei, which was consistent with levels of urbanization. Fluorine chemical industries allocated in Shandong and Liaoning played important roles in terms of point emission and contamination of PFASs, dominated by perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). Intensive anthropogenic activities involved in urbanization possibly resulted in increasing releases of PFASs from industrial and domestic sources. PMID:25645059

Meng, Jing; Wang, Tieyu; Wang, Pei; Zhang, Yueqing; Li, Qifeng; Lu, Yonglong; Giesy, John P

2015-04-01

57

Perfluoroalkyl acid contamination of follicular fluid and its consequence for in vitro oocyte developmental competence.  

PubMed

Perfluoroalkyl acids (PFAAs) have been shown to induce negative effects in laboratory animals and in vitro experiments. Also, PFAAs have been detected in human tissues and body fluids. The ovarian follicle constitutes a fragile micro-environment where interactions between hormones, growth factors, the oocyte and surrounding somatic cells are essential to generate a fully competent oocyte. In vitro experiments suggest that PFAAs can influence this balance, but very scarce in vivo data are available to confirm this assumption. In fact, the potential PFAA-presence in the follicular micro-environment is currently unknown. Therefore, we investigated if PFAAs are present in human follicular fluid and if their presence could be a risk factor for in vivo exposed developing oocytes. Furthermore, we compared the PFAA-distribution within serum and follicular fluid. PFAAs were analyzed by LC/MS in follicular fluid (n=38) and serum (n=20) samples from women undergoing assisted reproductive technologies (ARTs). Statistical models were used to investigate PFAA-distribution in both body fluids, to compare this behavior with the distribution of lipophilic organic pollutants and to explore the relationship between patient characteristics, ART-results and follicular fluid contamination. Perfluorooctane sulfonate (PFOS) was the PFAA found in the highest concentration in follicular fluid [7.5 (0.1-30.4) ng/mL] and serum [7.6 (2.8-12.5) ng/mL]. A new variable, Principal Component 1, representing the overall PFAA-contamination of the follicular fluid samples, was associated with a higher fertilization rate (p<0.05) and a higher proportion of top embryos relative to the amount of retrieved oocytes (p<0.05), after adjusting for age, estradiol-concentration, BMI, male subfertility and the presence of other organic pollutants as explanatory variables. To conclude, overall higher PFAA-contamination in the follicular micro-environment was associated with a higher chance of an oocyte to develop into a high quality embryo. Also, PFAAs have different distribution patterns between serum and follicular fluid compared to the lipophilic organic pollutants. Further research is of course crucial to confirm these new observations. PMID:25089690

Petro, Evi M L; D'Hollander, Wendy; Covaci, Adrian; Bervoets, Lieven; Fransen, Erik; De Neubourg, Diane; De Pauw, Ingrid; Leroy, Jo L M R; Jorssen, Ellen P A; Bols, Peter E J

2014-10-15

58

Degradation and crosslinking of perfluoroalkyl polyethers under X-ray irradiation in ultrahigh vacuum  

NASA Technical Reports Server (NTRS)

Degradation of three types of commercially available perfluoroalkyl polyethers (PFPE)-Demnum S200, Fomblin Z25, and Krytox 16256-by X-ray irradiation was studied by using X-ray photoemission spectroscopy (XPS) and a mass spectrometer under ultra-high-vacuum conditions. The carbons in the polymers were characterized by chemical shifts of Cls binding energies. Gaseous products containing COF2 and low-molecular-weight fluorocarbons were formed. From Fomblin Z25, which has acetal linkages (-OCF2O-), a large quantity of COF2 gas was evolved. Liquid products became tacky after a long irradiation time, and some did not dissolve in Freon. High-pressure liquid chromatography (HPLC) showed that molecular weight distribution became broader and that higher molecular weight polymers were formed from Demnum and Krytox. We concluded from these results that degradation and cross-linking took place simultaneously. Demnum crosslinked more easily than the other fluids. The time dependence of both XPS spectra of Cls and mass spectra showed that C-O-bonded carbons in PFPE'S were removed faster than other carbons. There was no substrate effect on the degradation reaction because the first-order rate constants calculated from the change of gaseous products were similar when stainless steel (440C) and gold-coated surfaces were used. Metal fluorides were formed on stainless steel during the reaction. A mechanism for the degradation of PFPE'S is discussed on the basis of their molecular structures.

Mori, Shigeyuki; Morales, Wilfredo

1989-01-01

59

Size and age-concentration relationships for perfluoroalkyl substances in stingray livers from eastern Australia.  

PubMed

While the literature has reported a widespread occurrence of perfluoroalkyl substances (PFASs) in marine biota, very limited studies have been dedicated to the southern hemisphere. Hepatic concentrations of nine PFAAs were analysed in 49 stranded stingrays from eastern Australia using liquid chromatograph coupled with tandem mass spectrometry and relationships with biological parameters (i.e. body size, age and sex) were investigated. Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) were the predominant compounds quantified, with hepatic concentrations varying from 2 to 117 and from 0.2 to 19 ng·g(-1) w.w., respectively. A negative correlation between the concentration of PFASs in the livers of 32 blue-spotted stingrays and the body size/age was found. This relationship was independent of the animal's sex. We postulate that the dependence on body size is related to differing uptake kinetics of the chemicals, after the sting rays were exposed to an increased level of the contaminants in their environment. Such a pollution event could be related to a severe flood event that occurred at this location a few months before the samples' collection. Our results indicate that the influence of the body size/age should be taken into account when estimating bioaccumulation parameters from environmental measurements or exposure levels of biota to PFASs. PMID:25108254

Baduel, Christine; Lai, Foon Yin; Townsend, Kathy; Mueller, Jochen F

2014-10-15

60

Effect of serum concentration on the cytotoxicity and sister chromatid exchange induction by a chemical carcinogen and by a diesel particulate extract in V79 hamster cells.  

PubMed

The role of serum concentration on the cytotoxicity and on the sister chromatid exchange (SCE)-induction by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and by a diesel particulate extract (DPE), a complex mixture, has been carried out on V79 cells. An increase of the serum concentration in the medium decreases the toxicity of these chemicals, and especially when they are dispersed first in serum. Although no influence of serum concentration on the number of spontaneous SCEs occurring in control cells has been observed, the increase of serum concentration leads to a decrease in SCE's induction in treated cells. Our results show that serum can protect cells from the cytotoxic and mutagenic action of MNNG and diesel extract. PMID:6697323

Coulomb, H M; Gu, Z W; Loireau, M P; Chouroulinkov, I

1984-02-01

61

Chemically defined serum-free and xeno-free media for multiple cell lineages.  

PubMed

Cell culture is one of the most common methods used to recapitulate a human disease environment in a laboratory setting. Cell culture techniques are used to grow and maintain cells of various types including those derived from primary tissues, such as stem cells and cancer tumors. However, a major confounding factor with cell culture is the use of serum and animal (xeno) products in the media. The addition of animal products introduces batch and lot variations that lead to experimental variability, confounds studies with therapeutic outcomes for cultured cells, and represents a major cost associated with cell culture. Here we report a commercially available serum-free, albumin-free, and xeno free (XF) media (Neuro-Pure(TM)) that is more cost-effective than other commercial medias. Neuro-Pure was used to maintain and differentiate various cells of neuronal lineages, fibroblasts, as well as specific cancer cell lines; without the use of contaminants such serum, albumin, and animal products. Neuro-Pure allows for a controlled and reproducible cell culture environment that is applicable to translational medicine and general tissue culture. PMID:25405151

Usta, Sümeyra Naz; Scharer, Christopher D; Xu, Jie; Frey, Teryl K; Nash, Rodney J

2014-10-01

62

Chemically defined serum-free and xeno-free media for multiple cell lineages  

PubMed Central

Cell culture is one of the most common methods used to recapitulate a human disease environment in a laboratory setting. Cell culture techniques are used to grow and maintain cells of various types including those derived from primary tissues, such as stem cells and cancer tumors. However, a major confounding factor with cell culture is the use of serum and animal (xeno) products in the media. The addition of animal products introduces batch and lot variations that lead to experimental variability, confounds studies with therapeutic outcomes for cultured cells, and represents a major cost associated with cell culture. Here we report a commercially available serum-free, albumin-free, and xeno free (XF) media (Neuro-PureTM) that is more cost-effective than other commercial medias. Neuro-Pure was used to maintain and differentiate various cells of neuronal lineages, fibroblasts, as well as specific cancer cell lines; without the use of contaminants such serum, albumin, and animal products. Neuro-Pure allows for a controlled and reproducible cell culture environment that is applicable to translational medicine and general tissue culture. PMID:25405151

Usta, Sümeyra Naz; Scharer, Christopher D.; Xu, Jie; Frey, Teryl K.

2014-01-01

63

Brominated flame retardants and perfluoroalkyl substances in sediments from the Czech aquatic ecosystem.  

PubMed

This study reports results of analysis of various groups of halogenated chemicals, including brominated flame retardants (BFRs), such as polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), tetrabromobisphenol A (TBBPA) and perfluoroalkyl substances (PFASs) in 31 sediment samples collected in different localities of the Czech Republic. In this survey, identification of potential sources of these compounds was also performed; therefore several sampling sites located in highly industrialized areas were involved. Concentrations of target groups of analytes determined in sediments from several Czech rivers examined within this study decreased in the following order: decabromodiphenyl ether (BDE 209) > TBBPA~HBCDs~linear perfluorooctane sulfonate (L-PFOS)>other PBDEs~perfluorinated carboxylic acids (PFCAs)~perfluorooctane sulfonamide (FOSA). When compared the contamination by two monitored groups of halogenated compounds, the total content of ?BFRs was significantly higher, i.e. in the range from the method quantification limit (MQL) to 528 ?g/kg dry weight (dw) (median value 5.68 ?g/kg dw), than the total concentration of ?PFASs, that was in the range from MQL to 25.5 ?g/kg dw (median value 1.48 ?g/kg dw). The extremely highest content of BFR group (265-528 ?g/kg dw) was found in sediments collected in sampling sites on the Labe and Lužická Nisa Rivers, which are located in highly chemical industrialized areas and also in the sample from the locality Lampertice obtained from the sedimentation tank close to the factory processing and storing waste. These concentrations were a little bit higher or comparable to those found in similar highly industrialized areas worldwide. PMID:24140701

Hloušková, Veronika; Lanková, Darina; Kalachová, Kamila; Hrádková, Petra; Poustka, Jan; Hajšlová, Jana; Pulkrabová, Jana

2014-02-01

64

Neurotoxic effects of perfluoroalkylated compounds: mechanisms of action and environmental relevance.  

PubMed

Perfluoroalkylated compounds (PFCs) are used in fire-fighting foams, treatment of clothes, carpets and leather products, and as lubricants, pesticides, in paints and medicine. Recent developments in chemical analysis have revealed that fluorinated compounds have become ubiquitously spread and are regarded as a potential threats to the environment. Due to the carbon-fluorine bond, which has a very high bond strength, these chemicals are extremely persistent towards degradation and some PFCs have a potential for bioaccumulation in organisms. Of particular concern has been the developmental toxicity of PFOS and PFOA, which has been manifested in rodent studies as high mortality of prenatally exposed newborn rats and mice within 24 h after delivery. The nervous system appears to be one of the most sensitive targets of environmental contaminants. The serious developmental effects of PFCs have lead to the upcoming of studies that have investigated neurotoxic effects of these substances. In this review the major findings of the neurotoxicity of the main PFCs and their suggested mechanisms of action are presented. The neurotoxic effects are discussed in light of other toxic effects of PFCs to indicate the significance of PFCs as neurotoxicants. The main findings are that PFCs may induce neurobehavioral effects, particularly in developmentally exposed animals. The effects are, however, subtle and inconclusive and are often induced at concentrations where other toxic effects also are expected. Mechanistic studies have shown that PFCs may affect the thyroid system, influence the calcium homeostasis, protein kinase C, synaptic plasticity and cellular differentiation. Compared to other environmental toxicants the human blood levels of PFCs are high and of particular concern is that susceptible groups may be exposed to a cocktail of substances that in combination reach harmful concentrations. PMID:22456834

Mariussen, Espen

2012-09-01

65

Dialkylzinc-mediated cross-coupling reactions of perfluoroalkyl and perfluoroaryl halides with aryl halides.  

PubMed

A highly chemoselective perfluoroalkylation reaction of aromatic halides is reported. Thermally stable perfluoroalkylzinc reagents, generated by a rapid halogen-zinc exchange reaction between diorganozinc and perfluoroalkyl halide species, couple with a wide range of aryl halides in the presence of a copper catalyst, in moderate to high yields. Good stability of the perfluoroalkylzinc species was indicated by DFT calculation and the reagents were storable for at least three months under argon without loss of activity. This method is applicable to gram-scale synthesis, and its functional group tolerance compares favorably with reported protocols. PMID:25630706

Kato, Hisano; Hirano, Keiichi; Kurauchi, Daisuke; Toriumi, Naoyuki; Uchiyama, Masanobu

2015-03-01

66

Perfluoroalkyl chains direct novel self-assembly of insulin.  

PubMed

The self-assembly of biopharmaceutical peptides into multimeric, nanoscale objects, as well as their disassembly to monomers, is central for their mode of action. Here, we describe a bioorthogonal strategy, using a non-native recognition principle, for control of protein self-assembly based on intermolecular fluorous interactions and demonstrate it for the small protein insulin. Perfluorinated alkyl chains of varying length were attached to desB30 human insulin by acylation of the ?-amine of the side-chain of LysB29. The insulin analogues were formulated with Zn(II) and phenol to form hexamers. The self-segregation of fluorous groups directed the insulin hexamers to self-assemble. The structures of the systems were investigated by circular dichroism (CD) spectroscopy and synchrotron small-angle X-ray scattering. Also, the binding affinity to the insulin receptor was measured. Interestingly, varying the length of the perfluoroalkyl chain provided three different scenarios for self-assembly; the short chains hardly affected the native hexameric structure, the medium-length chains induced fractal-like structures with the insulin hexamer as the fundamental building block, while the longest chains lead to the formation of structures with local cylindrical geometry. This hierarchical self-assembly system, which combines Zn(II) mediated hexamer formation with fluorous interactions, is a promising tool to control the formation of high molecular weight complexes of insulin and potentially other proteins. PMID:22129241

Malik, Leila; Nygaard, Jesper; Hoiberg-Nielsen, Rasmus; Arleth, Lise; Hoeg-Jensen, Thomas; Jensen, Knud J

2012-01-10

67

Identification of Chemical Constituents in the Extract and Rat Serum from Ziziphus Jujuba Mill by HPLC-PDA-ESI-MSn  

PubMed Central

Chinese jujube (Ziziphus jujuba Mill.) has long been widely used for human consumption and medicinal purposes in China. It has been reported to possess several vital biological activities. However, the systematic study on the chemical constituents absorbed into plasma and their metabolites is still insufficient.A high-performance liquid chromatography-photodiode array detector-electrospray ionization ion-mass spectrometry (HPLC-PDA-ESI-MSn) method was established to analyze the ethanol extract in Ziziphus jujuba Mill and the constituents absorbed into rat serum. In the present study, a dose of 10 mL/Kg of ethanol extract of jujube, which is equivalent to 12.5 g crude dried herb/Kg, was orally administrated to rats. The main components were analyzed in the ethanol extract of Ziziphus jujuba Mill and the parent constituents and metabolites were studied in rat plasma samples after oral administration of the ethanol extract of jujube.D101 macroporous polystyrene resin was a good pretreatment method to obtain better separation and impurity removal effect. Twenty-two compounds were identified in the ethanol extract of Ziziphus jujuba Mill. Four parent compounds and four metabolites were detected in rat serum. Among them, seventeen compounds were reported for the first time. PMID:25276208

Wang, Shuping; Zhang, Jingze; Zhang, Zhidan; Gao, Wenyuan; Yan, Yanan; Li, Xia; Liu, Changxiao

2014-01-01

68

Patterns of clinical bioindicators in rat serum following acute exposure to pesticides of different chemical classes  

EPA Science Inventory

There is interest in bioindicators of adverse outcomes in safety assessment and translational research. Chemically-induced neurological effects may be reflected in specific neuronal changes and/or by general stress-like responses, and such bioindicators may be useful for measurin...

69

Perfluoroalkyl Acids in Drinking Water: Sources, Fate and Removal C. Eschauzier  

E-print Network

Perfluoroalkyl Acids in Drinking Water: Sources, Fate and Removal C. Eschauzier #12;Resumé thesis for the production of drinking water, if PFAAs are present in the groundwater they will most certainly pass through the treatment. More monitoring of groundwater abstraction areas is therefore recommended for the drinking water

van Rooij, Robert

70

Exposure and effects of perfluoroalkyl substances in tree swallows nesting in Minnesota and Wisconsin, USA  

EPA Science Inventory

The exposure and effects of perfluoroalkyl substances (PFASs) were studied at eight locations in Minnesota and Wisconsin between 2007 and 2011 using tree swallows (Tachycineta bicolor) as sentinel species. These eight sites covered a range of possible exposure pathways and ecolog...

71

Perfluoroalkyl compounds in Danish wastewater treatment plants and aquatic environments.  

PubMed

This study reports the results of a screening survey of perfluoroalkyl compounds (PFCs) in the Danish environment. The study included point sources (municipal and industrial wastewater treatment plants and landfill sites) and the marine and freshwater environments. Effluent and influent water and sewage sludge were analysed for point sources. Sediment, blue mussels (Mytilus edulis) and liver from plaice (Pleuronectes platessa), flounder (Platichthys flesus) and eel (Anguilla anguilla) were analysed for the freshwater and marine environments. The results obtained show a diffuse PFCs contamination of the Danish environment with concentrations similar to those measured in other countries with the absence of primary contamination sources such as fluorochemical production. PFOS and PFOA were generally the most dominating PFCs measured in both point sources and the aquatic environments. PFCs were found in both inflow and outflow water and sewage sludge from municipal and industrial wastewater treatment plants (WWTPs), indicating that WWTPs can be significant sources to PFCs in the environment. This is also reflected in the locally elevated PFCs concentrations found in fish like eels from shallow freshwater and marine areas. However, the highest PFCs concentrations found in fish in this study was in plaice from the Skagerrak (156 ng/g wet weight PFOS), but it is unknown if this can be related to significant sources in the North Sea region or to differences between species. The concentrations of PFCs were below the detection limit in all analysed freshwater and marine samples of sediment and mussels. Despite the relatively low PFCs concentrations measured in marine fish, the high bioaccumulation potential of PFCs, particularly PFOS, may lead to high concentrations of PFCs in marine mammals as shown by previous investigations. PMID:18029290

Bossi, R; Strand, J; Sortkjaer, O; Larsen, M M

2008-05-01

72

Occurrence of perfluoroalkyl acids in environmental waters in Vietnam.  

PubMed

This is the first nationwide study of perfluoroalkyl acids (PFAAs) in environmental waters in Vietnam. Twenty-eight river water and 22 groundwater samples collected in four major cities and 14 river water samples from the Red River were screened to investigate the occurrence and sources of 16 PFAAs. Perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) were the most prevalent of 11 detected PFAAs with maximum concentrations in urban river water of 5.3, 18 and 0.93ngL(-1), respectively, and in groundwater of 8.2, 4.5 and 0.45ngL(-1), respectively. PFAAs in the Red River water were detected at low levels. PFAA concentrations in river water were higher in the rainy season than in the dry season, possibly due to storm water runoff, a common phenomenon in Southeast Asian countries. The highest concentrations of PFAAs in river water were observed in samples from highly populated and industrialized areas, perhaps sourced from sewage. The PFAA concentrations observed were similar to those in other Southeast Asian countries, but lower than in developed nations. From the composition profiles of PFAAs, industrial products containing PFAAs imported from China and Japan might be one of the major sources of PFAAs in the Vietnamese aquatic environment. According to the health-based values and advisory issued by the United States Environmental Protection Agency (USEPA), the concentrations of detected PFAAs in this study do not pose an immediate health risk to humans and aquatic organisms. PMID:25496738

Duong, Hanh Thi; Kadokami, Kiwao; Shirasaka, Hanako; Hidaka, Rento; Chau, Hong Thi Cam; Kong, Lingxiao; Nguyen, Trung Quang; Nguyen, Thao Thanh

2015-03-01

73

Fluorinated alternatives to long-chain perfluoroalkyl carboxylic acids (PFCAs), perfluoroalkane sulfonic acids (PFSAs) and their potential precursors.  

PubMed

Since 2000 there has been an on-going industrial transition to replace long-chain perfluoroalkyl carboxylic acids(PFCAs), perfluoroalkane sulfonic acids (PFSAs) and their precursors. To date, information on these replacements including their chemical identities, however, has not been published or made easily accessible to the public, hampering risk assessment and management of these chemicals. Here we review information on fluorinated alternatives in the public domain. We identify over 20 fluorinated substances that are applied in [i] fluoropolymer manufacture, [ii] surface treatment of textile, leather and carpets, [iii] surface treatment of food contact materials,[iv] metal plating, [v] fire-fighting foams, and [vi] other commercial and consumer products.We summarize current knowledge on their environmental releases, persistence, and exposure of biota and humans. Based on the limited information available, it is unclear whether fluorinated alternatives are safe for humans and the environment.We identify three major data gaps that must be filled to perform meaningful risk assessments and recommend generation of the missing data through cooperation among all stakeholders (industry, regulators, academic scientists and the public). PMID:24660230

Wang, Zhanyun; Cousins, Ian T; Scheringer, Martin; Hungerbühler, Konrad

2013-10-01

74

Characterization of cultured rat oligodendrocytes proliferating in a serum-free, chemically defined medium  

SciTech Connect

A serumless, chemically defined medium has been developed for the culture of oligodendrocytes isolated from primary neonatal rat cerebral cultures. Combined together, insulin, transferrin, and fibroblast growth factor synergistically induced an essentially homogeneous population (95-98%) of cells expressing glycerol-3-phosphate dehydrogenase activity to undergo cell division. Proliferating cells were characterized by several criteria: (i) ultrastructural analysis by transmission electron microscopy identified the cell type as an oligodendrocyte; (ii) biochemical assays showed expression of three oligodendrocyte biochemical markers, induction of both glycerol phosphate dehydrogenase and lactate dehydrogenase, and presence of 2',3'-cyclic nucleotide 3'-phosphodiesterase; and (iii) immunocytochemical staining showed cultures to be 95-98% positive for glycerol phosphate dehydrogenase, 90% for myelin basic protein, 60-70% for galactocerebroside, and 70% for A2B5.

Saneto, R.P.; de Vellis, J.

1985-05-01

75

Comparison of chemical-activated luciferase gene expression bioassay and gas chromatography for PCB determination in human serum and follicular fluid.  

PubMed

We assessed exposure to dioxin-like compounds using chemical and bioassay analysis in different matrices in a female population. A total of 106 serum and 9 follicular fluid samples were collected from infertile women attending Centers for Reproductive Medicine in Belgium from 1996 to 1998. Major polychlorinated biphenyl (PCB) congeners were quantified by chemical analysis using gas chromatography with electron-capture detection, and the chemical-activated luciferase gene expression (CALUX) bioassay was used to determine the total dioxin-like toxic equivalence (TEQ) of mixtures of polyhalogenated aromatic hydrocarbons present in body fluids, such as serum and follicular fluid. To the best of our knowledge, this is the first investigation to determine TEQ values by the CALUX bioassay in follicular fluid. The TEQ levels in both matrices are well correlated (r = 0.83, p = 0.02). As the chemical and bioassay analysis executed in this study do not cover the same span of polyhalogenated aromatic hydrocarbons, we did not expect totally correlated results. Moreover, the sample workup and quantification of the analytes differed completely. Nonetheless, the TEQ values in human extracts correlated well with the sum of four major PCB congeners chemically determined in both serum and follicular fluid. These results indicate that the CALUX bioassay may serve as a simple, relatively inexpensive prescreening tool for exposure assessment in epidemiologic surveys. PMID:10856030

Pauwels, A; Cenijn, P H; Schepens, P J; Brouwer, A

2000-06-01

76

Assessment of perfluoroalkyl substances in food items at global scale.  

PubMed

This study assessed the levels of 21 perfluoroalkyl substances (PFASs) in 283 food items (38 from Brazil, 35 from Saudi Arabia, 174 from Spain and 36 from Serbia) among the most widely consumed foodstuffs in these geographical areas. These countries were chosen as representatives of the diet in South America, Western Asia, Mediterranean countries and South-Eastern Europe. The analysis of foodstuffs was carried out by turbulent flow chromatography (TFC) combined with liquid chromatography with triple quadrupole mass spectrometry (LC-QqQ-MS) using electrospray ionization (ESI) in negative mode. The analytical method was validated for the analysis of different foodstuff classes (cereals, fish, fruit, milk, ready-to-eat foods, oil and meat). The analytical parameters of the method fulfill the requirements specified in the Commission Recommendation 2010/161/EU. Recovery rates were in the range between 70% and 120%. For all the selected matrices, the method limits of detection (MLOD) and the method limits of quantification (MLOQ) were in the range of 5 to 650 pg/g and 17 to 2000 pg/g, respectively. In general trends, the concentrations of PFASs were in the pg/g or pg/mL levels. The more frequently detected compounds were perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutanoic acid (PFBA). The prevalence of the eight-carbon chain compounds in biota indicates the high stability and bioaccumulation potential of these compounds. But, at the same time, the high frequency of the shorter chain compounds is also an indication of the use of replacement compounds in the new fluorinated materials. When comparing the compounds profile and their relative abundances in the samples from diverse origin, differences were identified. However, in absolute amounts of total PFASs no large differences were found between the studied countries. Fish and seafood were identified as the major PFASs contributors to the diet in all the countries. The total sum of PFASs in fresh fish and seafood was in the range from the MLOQ to 28ng/g ww. According to the FAO-WHO diets composition, the daily intake (DI) of PFASs was calculated for various age and gender groups in the different diets. The total PFASs food intake was estimated to be between 2300 and 3800 ng /person per day for the different diets. Finally, the risk intake (RI) was calculated for selected relevant compounds. The results have indicated that by far in no case the tolerable daily intake (TDI) (150, 1500, 50,000, 1,000,000, 150, 1500 ng/kg body weight, for perfluorohexanesulfonate (PFHxS), fluorotelomer alcohol (FTOH), perfluorobutanesulfonic acid (PFBS), perfluorobutanoic acid (PFBA), PFOS and PFOA, respectively) was exceeded. PMID:25282275

Pérez, Francisca; Llorca, Marta; Köck-Schulmeyer, Marianne; Škrbi?, Biljana; Oliveira, Luis Silva; da Boit Martinello, Kátia; Al-Dhabi, Naif A; Anti?, Igor; Farré, Marinella; Barceló, Damiŕ

2014-11-01

77

Application of 31P NMR Spectroscopy and Chemical Derivatization for Metabolite Profiling of Lipophilic Compounds in Human Serum  

PubMed Central

New methods for obtaining metabolic fingerprints of biological samples with improved resolution and sensitivity are highly sought for early disease detection, studies of human health and pathophysiology, and for better understanding systems biology. Considering the complexity of biological samples, interest in biochemical class selection through the use of chemoselective probes for improved resolution and quantitation is increasing. Considering the role of lipids in the pathogenesis of a number of diseases, in this study fingerprinting of lipid metabolites was achieved by 31P labeling using the derivatizing agent 2-chloro-4,4,5,5-tetramethyldioxaphospholane. Lipids containing hydroxyl, aldehyde and carboxyl groups were selectively tagged with 31P and then detected with good resolution using 31P NMR by exploiting the 100% natural abundance and wide chemical shift range of 31P. After standardizing the reaction conditions using representative compounds, the derivatization approach was used to profile lipids in human serum. The results show that the 31P derivatization approach is simple, reproducible and highly quantitative, and has the potential to profile a number of important lipids in complex biological samples. PMID:19610016

DeSilva, M. Aruni; Shanaiah, Narasimhamurthy; Gowda, G. A. Nagana; Rosa-Pérez, Kellymar; Hanson, Bryan A.; Raftery, Daniel

2010-01-01

78

Chemical Immobilization of Sloth Bears (Melursus ursinus) with Ketamine Hydrochloride and Xylazine Hydrochloride: Hematology and Serum Biochemical Values  

PubMed Central

The present study was conducted to define the physiological responses of captive sloth bears immobilized with ketamine hydrochloride and xylazine hydrochloride and to determine and compare the values of hematology and serum biochemical parameters between sexes. A total of 15 sloth bears were immobilized using combination of ketamine hydrochloride and xylazine hydrochloride drugs at the dose rate of 5.0?milligram (mg) per kg body weight and 2.0?mg per kg body weight, respectively. The use of combination of these drugs was found satisfactory for the chemical immobilization of captive sloth bears. There were no significant differences observed in induction time and recovery time and physiological parameters such as heart rate, respiratory rate, and rectal temperature between sexes. Health related parameters comprising hematological values like packed cell volume (PCV), hemoglobin (Hb), red blood cell count (RBC), erythrocyte indices, and so forth and biochemical values like total protein, blood urea nitrogen (BUN), creatinine, alkaline amino-transferase (ALT), aspartate amino-transferase (AST), and so forth were estimated in 11 (5 males and 6 females) apparently healthy bears. Comparison between sexes revealed significant difference in PCV (P < 0.05) and mean corpuscular hemoglobin concentration (MCHC) (P < 0.05). The study might help to evaluate health profiles of sloth bears for appropriate line treatment. PMID:24876990

Veeraselvam, M.; Sridhar, R.; Perumal, P.; Jayathangaraj, M. G.

2014-01-01

79

Perfluoroalkyl substances detected in the world's southernmost marine mammal, the Weddell seal (Leptonychotes weddellii).  

PubMed

This study investigates concentrations of 18 perfluoroalkyl substances (PFAS) in blood plasma of adult lactating Weddell seals (Leptonychotes weddellii) (n = 10) from McMurdo Sound, Antarctica. Perfluoroundecanoic acid (PFUnDA) was detected in all samples at concentrations ranging from 0.08 to 0.23 ng/ml. Perfluorooctane sulfonate (PFOS), perfluorohexanoate (PFHxA) and perfluorotridecanoate (PFTriDA) were sporadically detected, while the remaining compounds were below the limit of detection. This is the first report of detectible concentrations of PFASs in an endemic Antarctic marine mammal species. We suggest that the pollutants have been subjected to long range atmospheric transportation and/or derive from a local source. A review of these and published data indicate that perfluoroalkyl carboxylates (PFCAs) dominate in biotic PFAS patterns in species feeding south of the Antarctic Circumpolar Current (ACC), whereas PFOS was the major PFAS detected in species feeding predominantly north of the current. PMID:25497307

Routti, Heli; Krafft, Bjřrn A; Herzke, Dorte; Eisert, Regina; Oftedal, Olav

2015-02-01

80

Variable effects of chemical allergens on serum IgE concentration in mice. Preliminary evaluation of a novel approach to the identification of respiratory sensitizers.  

PubMed

A wide variety of chemicals may induce allergic contact dermatitis (contact sensitivity). Some chemical allergens may, in addition, cause respiratory sensitization. Topical exposure of mice to contact and respiratory chemical sensitizers results in the initiation of divergent immune responses characteristic of preferential activation of different functional subpopulations of T helper (TH) cells. In the present study we have sought to make use of these differences, particularly differences in the ability of contact and respiratory allergens to provoke IgE responses, and to question whether opportunities exist for the identification of chemicals with the potential for respiratory sensitization. We have examined alterations in the serum concentration of IgE following topical exposure of mice to seven chemical allergens; trimellitic anhydride (TMA), phthalic anhydride, diphenylmethane-4,4'-diisocyanate (MDI), dicyclohexylmethane-4,4'-diisocyanate (HMDI), isophorone diisocyanate (IPDI), oxazolone and 2,4-dinitrochlorobenzene (DNCB). Three of these--TMA, phthalic anhydride and MDI--are known human respiratory sensitizers. The other four--HMDI, IPDI, oxazolone and DNCB--appear not to cause respiratory allergy, or at least have a very limited potential to do so. At the concentrations tested, exposure to all chemicals caused a lymphocyte proliferative response in lymph nodes draining the site of application. However, exposure only to TMA, phthalic anhydride and MDI resulted in a substantial increase in the concentration of serum IgE. Treatment with HMDI and IPDI failed to induce any change in serum IgE concentration. DNCB and oxazolone caused only small and transient elevations of IgE that were considerably less marked than those observed with respiratory sensitizers.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1447476

Dearman, R J; Basketter, D A; Kimber, I

1992-10-01

81

[Determination of serum copper and zinc in different chemical forms by graphite furnace atomic absorption spectrometry with ethanol-EDTA precipitation method].  

PubMed

A simple and reliable method was developed for the determination of serum copper and zinc in different chemical forms by graphite furnace atomic absorption spectrometry (GFAAS) with ethanol-EDTA precipitation. The serum and ethanol were mixed with volume ratio 1 : 2. The mixture was incubated at 70 degrees C and ultra-centrifuged to precipitate proteins. Zinc and copper can be released from albumin after EDTA treating. Thus, macroglobulin-zinc, ceruloplasmin-copper, and albumin-bound zinc or copper could be determined by two proposed precipitation steps. The determination limit of copper (3sigma) was 1.2 microg x L(-1) and the recovery was 92.3%-104%, while the determination limit of zinc (3sigma) was 0.098 microg x L(-1), and the recovery was 90%-107%. This two-step precipitation method can be used to determine serum zinc and copper in various chemical forms in tumor, Wilson patients and heathy human. PMID:20496717

Zhang, Yuan; Li, Zhe-Xuan; Li, Hui; Peng, Lin; Luo, Hong-Jun; Li, Wei-Qiu; Luo, Wen-Hong

2010-03-01

82

Theoretical study on the dissociation energies, ionization potentials and electron affinities of three perfluoroalkyl iodides  

NASA Astrophysics Data System (ADS)

Dissociation energies, ionization potentials and electron affinities of three perfluoroalkyl iodides, CF 3I, C 2F 5I, and i-C 3F 7I are calculated accurately with B3LYP, MP n ( n = 2-4), QCISD, QCISD(T), CCSD, and CCSD(T) methods. Calculations are performed by using large-core correlation-consistent pseudopotential basis set (SDB-aug-cc-pVTZ) for iodine atom. In all energy calculations, the zero point vibration energy is corrected. And the basis set superposition error is corrected by counterpoise method in the calculation of dissociation energy. Theoretical results are compared with the experimental values.

Cheng, Li; Shen, Zuochun; Lu, Jianye; Gao, Huide; Lü, Zhiwei

2005-11-01

83

TOXICOGENOMIC STUDY OF TRIAZOLE FUNGICIDES AND PERFLUOROALKYL ACIDS  

EPA Science Inventory

Toxicogenomic analysis of five environmental contaminants was performed to investigate the ability of genomics to categorize chemicals and elucidate mechanisms of toxicity. Three triazole antifungals (myclobutanil, propiconazole and triadimefon) and two perfluorinated compounds (...

84

Perfluoroalkyl acids in selected wastewater treatment plants and their discharge load within the Lake Victoria basin in Kenya.  

PubMed

A major ecological challenge facing Lake Victoria basin is the influx of chemical contaminants from domestic, hospital, and industrial effluents. Determined levels of perfluoroalkyl acids (PFAAs) in wastewater and sludge from selected wastewater treatment plants (WWTPs) in Kenya are presented and their daily discharge loads calculated for the first time within the Lake Victoria basin. Samples were extracted and separated using solid-phase extraction and ultra-performance liquid chromatography (UPLC)-MS/MS or LC-MS/MS methodology. All sewage sludge and wastewater samples obtained from the WWTPs contained detectable levels of PFAAs in picogram per gram dry weight (d.w.) and in nanogram per liter, respectively. There was variability in distribution of PFAAs in domestic, hospital, and industrial waste with domestic WWPTs observed to contain higher levels. Almost all PFAA homologues of chain length C-6 and above were detected in samples analyzed, with long-chain PFAAs (C-8 and above chain length) being dominant. The discharge from hospital contributes significantly to the amounts of PFAAs released to the municipal water systems and the lake catchment. Using the average output of wastewater from the five WWTPs, a mass load of 1013 mg day(-1) PFAAs per day discharged has been calculated, with the highest discharge obtained at Kisumu City (656 mg day(-1)). The concentration range of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in wastewater was 1.3-28 and 0.9-9.8 ng L(-1) and in sludge samples were 117-673 and 98-683 pg g(-1), respectively. PMID:25861900

Chirikona, Florah; Filipovic, Marko; Ooko, Seline; Orata, Francis

2015-05-01

85

In situ fate and partitioning of waterborne perfluoroalkyl acids (PFAAs) in the Youngsan and Nakdong River Estuaries of South Korea.  

PubMed

Concentrations, distributions, fate, and partitioning of perfluoroalkyl acids (PFAAs) were investigated in surface water (n=34) collected from the Youngsan and Nakdong River Estuaries of South Korea. Thirteen individual PFAAs in water and suspended solids (SS) were quantified by use of HPLC-MS/MS. PFAAs were detected in all samples, which indicated that they were widely distributed in the study area. Greater concentrations of PFAAs were found at some inland sites which seemed to be affected by direct input from point sources, such as wastewater treatment plants, and/or indirect diffusive sources, such as surface runoff. Spatial distributions of PFAAs in estuaries along transects toward the open sea demonstrated that these chemicals were transported to the outer region primarily by water discharged during the rainy season. Field-based partition coefficients (K(d)) for long-chain PFAAs (C?8) were significantly correlated with salinity (r(2)=0.48 to 0.73, p<0.01); K(d) values increased exponentially as a function of salinity. Due to the 'salting-out' effect, PFAAs were largely scavenged by adsorption onto SS and/or sediments in estuarine environments. In addition, values for K(d) of those PFAAs were directly proportional to the number of carbon atoms in the PFAAs. Salting constants of selected PFAAs were notably greater than those of other environmental organic contaminants, which indicated that adsorption of PFAAs is largely associated with salinity. Overall, the results of the present study will provide better understanding of the fate and transport of PFAAs in the zone of salinity boundary that can be used for developing fate models of PFAAs in the coastal marine environment. PMID:23333509

Hong, Seongjin; Khim, Jong Seong; Park, Jinsoon; Kim, Minhee; Kim, Woong-Ki; Jung, Jinho; Hyun, Seunghun; Kim, Jeong-Gyu; Lee, Hyojin; Choi, Heeseon J; Codling, Garry; Giesy, John P

2013-02-15

86

Determining a Robust D-Optimal Design for Testing for Departure from Additivity in a Mixture of Four Perfluoroalkyl Acids.  

EPA Science Inventory

Our objective is to determine an optimal experimental design for a mixture of perfluoroalkyl acids (PFAAs) that is robust to the assumption of additivity. PFAAs are widely used in consumer products and industrial applications. The presence and persistence of PFAAs, especially in ...

87

Evaluating the additivity of perfluoroalkyl acids (PFAAs) in binary combinations on peroxisome proliferator-activated receptor-a(PPARa) activation  

EPA Science Inventory

Perfluoroalkyl acids (PFAAs) are found globally in the environment, detected in humans and wildlife, and are typically present as mixtures of PFAA congeners. Mechanistic studies have found that responses to PFAAs are mediated in part by PPARa. Our previous studies showed that ind...

88

Condensed-Phase, Halogen-Bonded CF3 I and C2 F5 I Adducts for Perfluoroalkylation Reactions.  

PubMed

A family of practical, liquid trifluoromethylation and pentafluoroethylation reagents is described. We show how halogen bonding can be used to obtain easily handled liquid reagents from gaseous CF3 I and CF3 CF2 I. The synthetic utility of the new reagents is exemplified by a novel direct arene trifluoromethylation reaction as well as adaptations of other perfluoroalkylation reactions. PMID:25651531

Sladojevich, Filippo; McNeill, Eric; Börgel, Jonas; Zheng, Shao-Liang; Ritter, Tobias

2015-03-16

89

Calcium-Regulated Differentiation of Normal Human Epidermal Keratinocytes in Chemically Defined Clonal Culture and Serum-Free Serial Culture  

Microsoft Academic Search

An improved serum-free culture system has been developed for normal human epidermal keratinocytes (HK), Short-term clonal growth and differentiation studies are routinely performed in a defined medium consisting of optimized nutrient medium MCDB 153 supplemented with epidermal growth factor, insulin, hydrocortisone, ethanolamine, and phosphoethanolamine. A small amount of whole bovine pituitary extract (wBPE) is added for initiation of primary cultures,

Steven T. Boyce; Richard G. Ham

1983-01-01

90

Influence of renal impairment, chemical form, and serum protein binding on intravenous and oral aluminum kinetics in the rabbit.  

PubMed

The influence of renal impairment on the intravenous kinetics of aluminum (Al) lactate and the oral absorption of eight representative Al forms was determined. The serum protein binding of Al was assessed. Creatinine clearance in renally impaired rabbits was 23% of controls. Systemic clearance of Al was less in renally impaired rabbits (39 vs. 53 ml/hr/kg), as were the steady-state volume of distribution (516 vs. 1175 ml/kg), the half-life of elimination (14 vs. 27 hr), and the mean residence time of Al (14 vs. 25 hr). The shorter Al half-life and mean residence time in renally impaired rabbits were due to a diminished volume of Al distribution. Oral bioavailability of Al in renally intact rabbits ranged from 0.3 to 2.2% (Al borate less than glycinate less than hydroxide less than chloride less than sucralfate less than lactate less than nitrate less than citrate). Renal impairment had little influence on oral bioavailability of most Al forms, although it increased Al citrate absorption to 4.6%. In vitro and in vivo determination of Al ultrafilterability (less than 30,000 D) as an estimate of serum protein binding suggested a greater percentage of ultrafilterable Al species in renally impaired rabbit serum than in control rabbit serum. The increase in ultrafilterable Al species produced the less than expected reduction in Al clearance in renally impaired rabbits. The ultrafilterability of various Al concentrations was greater for citrate greater than lactate greater than nitrate greater than chloride, perhaps partially explaining the similar rank order of oral absorption of these Al forms. The physicochemistry of the eight Al forms was further characterized by determination of their octanol/water partitioning coefficients and their water solubility. There was a significant correlation between the percentage absorbed and the log of the octanol/water partition coefficient. Knowledge of the physicochemistry of Al aids in the understanding of Al pharmacokinetics. PMID:3413794

Yokel, R A; McNamara, P J

1988-08-01

91

Occurrence and point source characterization of perfluoroalkyl acids in sewage sludge.  

PubMed

The occurrence and levels of perfluoroalkyl acids (PFAAs) emitted from specific pollution sources into the aquatic environment in Switzerland were studied using digested sewage sludges from 45 wastewater treatment plants in catchments containing a wide range of potential industrial emitters. Concentrations of individual PFAAs show a high spatial and temporal variability, which infers different contributions from industrial technologies and activities. Perfluorooctane sulfonic acid (PFOS) was generally the predominant PFAA with concentrations varying between 4 and 2440?gkg(-1) (median 75?gkg(-1)). Elevated emissions were especially observed in catchments capturing discharges from metal plating industries (median 82?gkg(-1)), aqueous firefighting foams (median 215?gkg(-1)) and landfill leachates (median 107?gkg(-1)). Some elevated perfluoroalkyl carboxylic acids (PFCAs) levels could be attributed to emissions from textile finishing industries with concentrations up to 233?gkg(-1) in sewage sludge. Assuming sorption to sludge for PFOS and PFCAs of 15% and 2%, respectively, concentrations in wastewater effluents up to the low ?gL(-1) level were estimated. Even if wastewater may be expected to be diluted between 10 and 100 times by the receiving waters, elevated concentrations may be reached at specific locations. Although sewage sludge is a minor compartment for PFAAs in WWTPs, these investigations are helpful for the identification of hot-spots from industrial emitters as well as to estimate monthly average concentrations in wastewater. PMID:25176581

Alder, Alfredo C; van der Voet, Juergen

2015-06-01

92

Distribution of antifouling biocides and perfluoroalkyl compounds in sediments from selected locations in Indonesian coastal waters.  

PubMed

Coastal marine environments are considered to be the most sensitive areas for the accumulation of organotin (OT) compounds and other emerging new pollutants, such as perfluoroalkyl compounds. Contamination by these compounds is a matter of great concern due to their accumulation and possible negative impact on the coastal environment and organisms. The concentrations of tributyltin (TBT) compounds were greater in Indonesia, i.e., on the order of Bitung > Manado > Jakarta Bay > Gangga Island, and TBT in sediment from Bitung and Manado was the dominant species among butyltin (BT) compounds. Sea Nine 211, diuron, and irgarol 1051 were detected among alternative biocides in Bitung, Manado, and Gangga Island and irgarol 1051 was detected in Jakarta Bay. Perfluorooctanoic acid (PFOA) and perfluorosulfonic acid (PFOS) in Jakarta Bay were detected at 0.25 to 6.1 ?g kg(-1) dry weight (dw) and 0.58 to 3.7 ?g kg(-1) dw, respectively, and the concentrations of PFOS at most sampling sites were greater than those of PFOA. Thus, coastal waters from Indonesia have already been contaminated by antifouling biocides and perfluoroalkyl compounds. PMID:22569989

Harino, Hiroya; Arifin, Zainal; Rumengan, Inneke F M; Arai, Takaomi; Ohji, Madoka; Miyazaki, Nobuyuki

2012-07-01

93

Survey of perfluoroalkyl acids (PFAAs) and their precursors present in Japanese consumer products.  

PubMed

Perfluoroalkyl acids (PFAAs) and their precursors have been used in various consumer products. However, limited information regarding their occurrence and concentration levels in products is available. In this study, we investigated 18 PFAAs and 14 PFAA precursors in various categories of consumer products purchased in Japan. Relatively high total concentrations of PFAAs and their precursors were found in sprays for fabrics and textiles (perfluoroalkyl carboxylic acids (PFCAs) (carbon chain length?7) were also detected in greater concentrations than short chain PFCAs (?6). This result suggests that consumer products are one of the important sources of long-chain PFCAs in the environment. PMID:25753850

Ye, Feng; Zushi, Yasuyuki; Masunaga, Shigeki

2015-05-01

94

Amphiphilic perfluoroalkyl carbohydrates as new tools for liver imaging.  

PubMed

The synthesis of three molecules containing a fluorocarbon chain (either C(6)F(13), C(8)F(17) or C(10)F(21)), a sugar moiety (derived from lactobionic acid) and a chelate (derived from DTPA) is reported. These molecules (C(6)F(13)-Gal-DTPA, C(8)F(17)-Gal-DTPA or C(10)F(21)-Gal-DTPA) have been dispersed in water and their critical micellar concentration (CMC) as well as their size were determined. Their interaction with serum was weak as evaluated by time resolved fluorimetry of europium complexes. The presence of sugar on the surface of the nanoparticles was confirmed by the agglutination test using ricin. Conditions of pH and concentrations were optimised for in vivo studies. Finally, the nanoparticles formed with C(10)F(21)-Gal-DTPA have been complexed with (99m)Tc and injected to rats in order to follow their biodistribution by scintigraphy while following their stability by transmission electronic microscopy. A majority of the compound was found in the liver post-bolus injection. PMID:19501144

Richard, C; Chaumet-Riffaud, P; Belland, A; Parat, A; Contino-Pepin, C; Bessodes, M; Scherman, D; Pucci, B; Mignet, N

2009-09-11

95

Persistent organic pollutants measured in maternal serum and offspring neurodevelopmental outcomes--a prospective study with long-term follow-up.  

PubMed

Fetal exposure to persistent organic pollutants (POPs) has been linked to adverse neurodevelopment, but few studies have had follow-up beyond childhood. The purpose of this study was to examine the association of maternal serum concentrations of two perfluoroalkyl acids (perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS)), polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlorobenzene (HCB) with offspring behavioural and affective disorders and scholastic achievement in a prebirth cohort study with 20 years of follow up. Between 1988 and 1989 pregnant women (n=965) were recruited for the prebirth Danish Fetal Origins 1988 (DaFO88) Cohort in Aarhus, Denmark. Perfluoroalkyl acids, PCBs, p,p'-DDE, and HCB were quantified in serum from week 30 of gestation (n=876 for perfluoroalkyl acids/872 for PCBs, p,p'-DDE, HCB). Offspring were followed up through national registries until 2011. We evaluated associations between maternal serum concentrations of these POPs and offspring neurodevelopmental outcomes, defined as: first admission diagnosis or prescription of medication until age >20 for (1) ADHD; (2) depression; and (3) scholastic achievement defined as mean grade on a standardized written examination given in the 9th grade (final exams of compulsory school in Denmark). Maternal concentrations of organochlorine substances and perfluoroalkyl acids were higher than present day levels. During the follow-up period there were 27 (3.1%) cases of ADHD and 104 (11.9%) cases of depression; the mean scholastic achievement was 6.7 (SD 2.3). Overall we found no association for maternal levels of any of the measured pollutants with offspring behavioural and affective disorders or with scholastic achievement. Our analyses based on biomarkers from a cohort of over 800 pregnant women with long-term close to complete follow-up through national registries showed little evidence of a programming effect of PFOA, PFOS, PCBs, p,p'-DDE, and HCB in relation to clinically and functionally relevant offspring neurodevelopmental outcomes. PMID:24704638

Strřm, Marin; Hansen, Susanne; Olsen, Sjúrđur Fróđi; Haug, Line Smĺstuen; Rantakokko, Panu; Kiviranta, Hannu; Halldorsson, Thorhallur Ingi

2014-07-01

96

The effect of chlorination of estrogenic chemicals onthe level of serum vitellogenin of Japanese medaka (Oryzias latipes)  

Microsoft Academic Search

Abstract Mature male medaka were continually exposed to four chemicals, p-n-nonylphenol (p-n-NP), p- nonylphenol (p-NP), bisphenol-A (BPA) and 17?-estradiol (E2) to evaluate their estrogenic activities in the laboratory. In order to understand,the effect of the chlorination that is applied widely in water and waste- water treatment, the above chemicals were chlorinated and then exposed to mature male medaka. Furthermore, in

A. tabata; N. Miyamoto; Y. Ohnishi; M. Itoh; T. Yamada; T. Kamei; Y. Magara

97

Role of chemical structure in stereoselective recognition of beta-blockers and H1-antihistamines by human serum transferrin in capillary zone electrophoresis.  

PubMed

Studies on chiral resolution of beta-blocker and H1-antihistamine drugs by CZE using human serum transferrin are described. The drugs with different structures passed a pseudostationary protein zone in a coated capillary applying the partial filling method for the chiral separation. In this study we screened 15 compounds; most of them showed longer migration time, indicating an interaction with transferrin. Stereoselective interaction was observed only for five beta-blockers (celiprolol, talinolol, mepindolol, bopindolol, and oxprenolol) and for one H1-antihistamine (brompheniramine). The most important finding was that very small differences in the chemical structure of the drug resulted in significant changes in the stereoselective recognition. Resolution of mepindolol enantiomers was observed showing the essential role of one methyl group compared to pindolol, which is not resolved by transferrin. Bopindolol, also a derivative of pindolol having bigger difference in the structure, showed more experienced separation. The very slight difference between alprenolol and oxprenolol was also revealed with these methods, since only oxprenolol enantiomers, having an extra oxygen in the structure, are resolved. Determining the migration order of the eutomers and distomers (chlorpheniramine, brompheniramine) we can deduct conclusions about the role of serum proteins in the delivery of drugs within the body. PMID:16609932

Gagyi, László; Gyéresi, Arpád; Kilár, Ferenc

2006-04-01

98

Chemical composition of defatted strawberry and raspberry seeds and the effect of these dietary ingredients on polyphenol metabolites, intestinal function, and selected serum parameters in rats.  

PubMed

Strawberry and raspberry seeds were chemically analyzed and added as dietary ingredients to investigate the physiological response of rats. In both cases the main component was dietary fiber and the main polyphenols were ellagitannins (ET). The strawberry ET were mainly constituted by monomers and a dimer, agrimoniin, whereas raspberry ET were mainly constituted by a dimer, sanguiin-H-6, and a trimer, lambertianin-C. The lower content and the less polymerized structure of strawberry ET resulted in a higher cecal metabolites concentration (mainly nasutin and urolithin-A) in comparison to rats fed diet containing raspberry seeds. Dietary raspberry seeds, a source of dietary fiber, despite being richer in polyphenol compounds, were better utilized in fermentation processes, resulting in enhanced production of short-chain fatty acids. As opposed to strawberry seeds, the treatment with raspberry seeds beneficially improved the atherogenic index of a diet, mainly due to reduced triacylglycerol concentration in the serum. PMID:25746061

Kosmala, Monika; Zdu?czyk, Zenon; Ju?kiewicz, Jerzy; Jurgo?ski, Adam; Karli?ska, El?bieta; Macierzy?ski, Jakub; Ja?czak, Rafa?; Rój, Edward

2015-03-25

99

Levels and fate of perfluoroalkyl substances in beached plastic pellets and sediments collected from Greece.  

PubMed

Plastic debris damages marine wildlife and ecosystems becoming an important source of marine pollution. In addition, they can sorb, concentrate and stabilise contaminants acting as toxic carriers to the marine food web. In this context, the presence of 18 perfluoroalkyl substances (PFASs) in plastic pellets (n=5) and beach sediment (n=9) samples widely distributed around Greek coastal areas was assessed. The results, mainly, showed the sorption of PFASs onto pellet surface from surrounding water with concentrations from method limit of quantification to 115 ng/kg for C5, C7, C8 and C10 carboxylic acids and C8 sulfonate acid. A similar pattern was found by comparing plastic pellets and sediment for the same sampling locations that could indicate a common origin of contamination in both types of samples. However, since the number of analysed samples is limited, a more comprehensive study with a higher number of samples should be performed in future research. PMID:25172614

Llorca, Marta; Farré, Marinella; Karapanagioti, Hrissi K; Barceló, Damiŕ

2014-10-15

100

Acute and chronic toxicity of short chained perfluoroalkyl substances to Daphnia magna.  

PubMed

The aim of this study was to evaluate the aquatic toxicity of a C4-C6 chemistry based fluoroalkylated polymer and the perfluoroalkyl carboxylic acids, PFBA, PFHxA and PFOA to Daphnia magna. The acute toxicity decreased with decreasing carbon chain length, but the polymer did not show a dose related effect. In a chronic toxicity test performed with PFHxA, mortality was observed at similar concentrations as in the acute toxicity test, indicating that toxicity did not increase with increasing exposure time. Effects on mortality, reproduction and population growth rate occurred at similar concentrations, indicating no specific effect of PFHxA on sublethal endpoints. C4-C6 chemistry is thus less hazardous to daphnids than C7-C8 chemistry. Yet, these compounds are persistent, hard to remove from the environment and production volumes are increasing. PMID:25553346

Barmentlo, S Henrik; Stel, Jente M; van Doorn, Marijn; Eschauzier, Christian; de Voogt, Pim; Kraak, Michiel H S

2015-03-01

101

Perfluoroalkyl acids in various edible Baltic, freshwater, and farmed fish in Finland.  

PubMed

In this study, the concentration of perfluoroalkyl acids (PFAAs) in various edible Finnish Baltic Sea, freshwater, and farmed fish species were analysed. PFAAs were present in all the Baltic and freshwater species, but were not observed in any farmed fish. The most abundant compound in each species was perfluorooctane sulfonate (PFOS), comprising 41-100% of the total concentration. The total PFAA concentration varied considerably from 0.31 to 46ngg(-1) fresh weight. A notable variation in the PFAA concentrations implies that a single fish species alone is not suitable for monitoring PFAA contamination in a certain area. Our results confirm that wild domestic fish is one of the PFAA source in the Finnish diet. PMID:25262944

Koponen, Jani; Airaksinen, Riikka; Hallikainen, Anja; Vuorinen, Pekka J; Mannio, Jaakko; Kiviranta, Hannu

2015-06-01

102

Spatial distribution of perfluoroalkyl substances in surface sediments of five major rivers in china.  

PubMed

Perfluoroalkyl substances (PFASs) have received great attention from the public and scientific community due to their potential adverse impacts on the ecosystem and human health. We investigated the occurrence and distribution of 16 PFASs from 2 classes of PFASs-perfluoroalkyl carboxylic acids and perfluoroalkane sulfonic acids-in the archived surface sediments of five major rivers (Yellow River, Hai River, Liao River, Zhujiang River, and Dongjiang River) in northern and southern China. The study was also performed during the wet and dry seasons. Perfluorooctanoic acid and perfluorooctane sulfonic acid were the most frequently detected (detection frequency = 100 and 63 %, respectively) in the sediments of the five rivers; the concentrations ranged from 0.08 to 0.99 ng/g dry weight (dw) and were lower than the limit of detection (

Pan, Chang-Gui; Ying, Guang-Guo; Zhao, Jian-Liang; Liu, You-Sheng; Liu, Shuang-Shuang; Du, Jun; Kookana, Rai S

2015-04-01

103

Perfluoroalkyl substance concentrations in a terrestrial raptor: relationships to environmental conditions and individual traits.  

PubMed

Accumulation of persistent organic pollutants (POPs) in wildlife may be influenced by the physical and biotic environment, and concentrations vary greatly among areas, seasons, and individuals. Different hypotheses about sources of variation in perfluoroalkyl substance (PFAS) concentrations were examined in eggs (n?=?107) of tawny owls (Strix aluco) collected over a 24-yr period (1986-2009) in Norway. Predictor variables included the North Atlantic Oscillation (NAO), temperature, snow, food availability (vole abundance), and individual traits such as age, body condition, and clutch size. Concentrations of both perfluoro-octane sulfonate (PFOS) and perfluoroalkyl carboxylates (PFCAs) varied several fold in the population, both inter- and intra-annually. Moreover, individuals laid eggs with several times higher or lower PFAS concentrations within few years (1 yr-5 yr). After controlling for temporal trends (i.e., declining PFOS and increasing PFCA concentrations), both PFOS and PFCAs were positively associated to the winter NAO in the previous year (NAOy - 1 ), suggesting that atmospheric transport may be affecting the input of PFASs to the local ecosystem. Perfluoro-octane sulfonate was negatively related to temperature, but the pattern was complex as there was an interaction between temperature and the feeding conditions. The PFOS accumulation was highest in years with high vole abundance and low to medium temperatures. For PFCAs, there was an interaction between NAOy - 1 and feeding conditions, suggesting that strong air transport toward Norway and high consumption of voles led to a moderate increase in PFCA accumulation. The individual traits, however, had very little impact on the concentrations of PFASs in the eggs. The present study thus suggests that annual variation in environmental conditions influences the concentrations of PFASs in a terrestrial raptor such as the tawny owl. PMID:25323676

Bustnes, Jan O; Bangjord, Georg; Ahrens, Lutz; Herzke, Dorte; Yoccoz, Nigel G

2015-01-01

104

Investigating sources and pathways of perfluoroalkyl acids (PFAAs) in aquifers in Tokyo using multiple tracers.  

PubMed

We employed a multi-tracer approach to investigate sources and pathways of perfluoroalkyl acids (PFAAs) in urban groundwater, based on 53 groundwater samples taken from confined aquifers and unconfined aquifers in Tokyo. While the median concentrations of groundwater PFAAs were several ng/L, the maximum concentrations of perfluorooctane sulfonate (PFOS, 990 ng/L), perfluorooctanoate (PFOA, 1800 ng/L) and perfluorononanoate (PFNA, 620 ng/L) in groundwater were several times higher than those of wastewater and street runoff reported in the literature. PFAAs were more frequently detected than sewage tracers (carbamazepine and crotamiton), presumably owing to the higher persistence of PFAAs, the multiple sources of PFAAs beyond sewage (e.g., surface runoff, point sources) and the formation of PFAAs from their precursors. Use of multiple methods of source apportionment including principal component analysis-multiple linear regression (PCA-MLR) and perfluoroalkyl carboxylic acid ratio analysis highlighted sewage and point sources as the primary sources of PFAAs in the most severely polluted groundwater samples, with street runoff being a minor source (44.6% sewage, 45.7% point sources and 9.7% street runoff, by PCA-MLR). Tritium analysis indicated that, while young groundwater (recharged during or after the 1970s, when PFAAs were already in commercial use) in shallow aquifers (<50 m depth) was naturally highly vulnerable to PFAA pollution, PFAAs were also found in old groundwater (recharged before the 1950s, when PFAAs were not in use) in deep aquifers (50-500 m depth). This study demonstrated the utility of multiple uses of tracers (pharmaceuticals and personal care products; PPCPs, tritium) and source apportionment methods in investigating sources and pathways of PFAAs in multiple aquifer systems. PMID:24814036

Kuroda, Keisuke; Murakami, Michio; Oguma, Kumiko; Takada, Hideshige; Takizawa, Satoshi

2014-08-01

105

Hazard assessment of fluorinated alternatives to long-chain perfluoroalkyl acids (PFAAs) and their precursors: status quo, ongoing challenges and possible solutions.  

PubMed

Because of concerns over the impact of long-chain perfluoroalkyl acids (PFAAs) on humans and the environment, PFAAs and their precursors are being substituted by alternative substances including fluorinated alternatives that are structurally similar to the substances they replace. Using publicly accessible information, we aimed to identify the status quo of the hazard assessment of identified fluorinated alternatives, to analyze possible systemic shortcomings of the current industrial transition to alternative substances, and to outline possible solutions. Fluorinated alternatives, particularly short-chain PFAAs and perfluoroether carboxylic and sulfonic acids (PFECAs and PFESAs), possess high environmental stability and mobility implying that they have a high global contamination potential. In addition to their potential for causing global exposures, certain fluorinated alternatives have been identified as toxic and are thus likely to pose global risks to humans and the environment. Various factors, particularly the information asymmetry between industry and other stakeholders, have contributed to the current lack of knowledge about the risks posed by fluorinated alternatives. Available cases show that a non-fluorinated substitution strategy (employing either chemical or functionality substitutions) can be a possible long-term, sustainable solution and needs to be further developed and assessed. PMID:25461427

Wang, Zhanyun; Cousins, Ian T; Scheringer, Martin; Hungerbuehler, Konrad

2015-02-01

106

Development of a new chemically modified carbon paste electrode for selective determination of urinary and serum oxalate concentration.  

PubMed

The construction and evaluation of a novel modified carbon paste electrode with high selectivity toward oxalate ion are described. The constructed carbon paste potentiometric sensor for oxalate ion is based on the use of a zirconium salan complex as a good ionophore in the carbon paste matrix. The electrode exhibits a Nernstian slope of 29.1 mV/decade to oxalate ion over a wide concentration range from 1.5×10(-6) to 3.9 ×10(-2) mol L(-1) with a low detection limit of 7.0×10(-7) mol L(-1). The electrode possesses fast response time, satisfactory reproducibility, appropriate lifetime, and most importantly, good selectivity toward C2O4(2-) relative to a variety of common anions. The potentiometric response of the electrode is independent of the pH of the test solution in the pH range 2.5-8.0. The modified carbon paste electrode was successfully applied as an indicator electrode in potentiometric titration and potentiometric determination of oxalate ion in mineral water, blood serum and urine samples. PMID:24148425

Soleymanpour, Ahmad; Shafaatian, Bita; Mirfakhraei, Homeira Sadat; Rezaeifard, Abdolreza

2013-11-15

107

Cumulative health risk assessment of 17 perfluoroalkylated and polyfluoroalkylated substances (PFASs) in the Swedish population.  

PubMed

Humans are simultaneously exposed to a multitude of chemicals. Human health risk assessment of chemicals is, however, normally performed on single substances, which may underestimate the total risk, thus bringing a need for reliable methods to assess the risk of combined exposure to multiple chemicals. Per- and polyfluoroalkylated substances (PFASs) is a large group of chemicals that has emerged as global environmental contaminants. In the Swedish population, 17 PFASs have been measured, of which the vast majority lacks human health risk assessment information. The objective of this study was to for the first time perform a cumulative health risk assessment of the 17 PFASs measured in the Swedish population, individually and in combination, using the Hazard Index (HI) approach. Swedish biomonitoring data (blood/serum concentrations of PFASs) were used and two study populations identified: 1) the general population exposed indirectly via the environment and 2) occupationally exposed professional ski waxers. Hazard data used were publicly available toxicity data for hepatotoxicity and reproductive toxicity as well as other more sensitive toxic effects. The results showed that PFASs concentrations were in the low ng/ml serum range in the general population, reaching high ng/ml and low ?g/ml serum concentrations in the occupationally exposed. For those congeners lacking toxicity data with regard to hepatotoxicity and reproductive toxicity read-across extrapolations was performed. Other effects at lower dose levels were observed for some well-studied congeners. The risk characterization showed no concern for hepatotoxicity or reproductive toxicity in the general population except in a subpopulation eating PFOS-contaminated fish, illustrating that high local exposure may be of concern. For the occupationally exposed there was concern for hepatotoxicity by PFOA and all congeners in combination as well as for reproductive toxicity by all congeners in combination, thus a need for reduced exposure was identified. Concern for immunotoxicity by PFOS and for disrupted mammary gland development by PFOA was identified in both study populations as well as a need of additional toxicological data for many PFAS congeners with respect to all assessed endpoints. PMID:23792420

Borg, Daniel; Lund, Bert-Ove; Lindquist, Nils-Gunnar; Hĺkansson, Helen

2013-09-01

108

Brain region distribution and patterns of bioaccumulative perfluoroalkyl carboxylates and sulfonates in east greenland polar bears (Ursus maritimus).  

PubMed

The present study investigated the comparative accumulation of perfluoroalkyl acids (PFAAs) in eight brain regions of polar bears (Ursus maritimus, n?=?19) collected in 2006 from Scoresby Sound, East Greenland. The PFAAs studied were perfluoroalkyl carboxylates (PFCAs, C(6) -C(15) chain lengths) and sulfonates (C(4) , C(6) , C(8) , and C(10) chain lengths) as well as selected precursors including perfluorooctane sulfonamide. On a wet-weight basis, blood-brain barrier transport of PFAAs occurred for all brain regions, although inner regions of the brain closer to incoming blood flow (pons/medulla, thalamus, and hypothalamus) contained consistently higher PFAA concentrations compared to outer brain regions (cerebellum, striatum, and frontal, occipital, and temporal cortices). For pons/medulla, thalamus, and hypothalamus, the most concentrated PFAAs were perfluorooctane sulfonate (PFOS), ranging from 47 to 58?ng/g wet weight, and perfluorotridecanoic acid, ranging from 43 to 49?ng/g wet weight. However, PFOS and the longer-chain PFCAs (C(10) -C(15) ) were significantly (p??0.05) different among brain regions. The burden of the sum of PFCAs, perfluoroalkyl sulfonates, and perfluorooctane sulfonamide in the brain (average mass, 392?g) was estimated to be 46?µg. The present study demonstrates that both PFCAs and perfluoroalkyl sulfonates cross the blood-brain barrier in polar bears and that wet-weight concentrations are brain region-specific. PMID:23280712

Greaves, Alana K; Letcher, Robert J; Sonne, Christian; Dietz, Rune

2013-03-01

109

Polyfluoroalkyl phosphate esters and perfluoroalkyl carboxylic acids in target food samples and packaging--method development and screening.  

PubMed

Polyfluoroalkyl phosphate mono-, di-, and tri-esters (mono-, di-, and triPAPs) are used to water- and grease-proof food packaging materials, and these chemicals are known precursors to perfluoroalkyl carboxylic acids (PFCAs). Existing analytical methods for PAPs lack sample clean-up steps in the sample preparation. In the present study, a method based on ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC/MS/MS) was developed and optimized for the analysis of mono-, di-, and triPAPs, including a clean-up step for the raw extracts. The method was applied to food samples and their PAP-containing packaging materials. The optimized UPLC/MS/MS method enabled the separation and identification of a total of 4 monoPAPs, 16 diPAPs, and 7 triPAPs in the technical mixture Zonyl®-RP. For sample clean-up, weak anion exchange solid phase extraction columns were tested. PAPs standard solutions spiked onto the columns were separated into a fraction containing neutral compounds (triPAPs) and a fraction with ionic compounds (mono- and diPAPs) with recoveries between 72-110%. Method limits of quantification for food samples were in the sub to low picogram per gram range. For quantitative analysis of PAPs, compound-specific labeled internal standards showed to be essential as sorption and matrix effects were observed. Mono-, di-, and/or triPAPs were detected in all food packaging materials obtained from the Swedish market. Up to nine diPAPs were detected in the food samples, with the 6:2/6:2 and 6:2/8:2 diPAPs as the dominant compounds. DiPAP concentrations in the food samples ranged from 0.9 to 36 pg/g, which was comparable to individual PFCA concentrations in the same samples. Consumption of food packed in PAP-containing materials could be an indirect source of human exposure to PFCAs. PMID:23494682

Gebbink, Wouter A; Ullah, Shahid; Sandblom, Oskar; Berger, Urs

2013-11-01

110

Tissue specific uptake and elimination of perfluoroalkyl acids (PFAAs) in adult rainbow trout (Oncorhynchus mykiss) after dietary exposure.  

PubMed

Tissue specific uptake and elimination of perfluoroalkyl acids (PFAAs) were studied in rainbow trout (Oncorhynchus mykiss). Adult trout were exposed to perfluorobutane sulfonic acid (PFBS), perfluorohexane sulfonic acid (PFHxS), perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA) via food over a time period of 28d. In the following 28-d depuration period the fish were fed PFAA-free food. At defined sampling times four animals were removed from the experimental tank, euthanized and dissected. Muscle, liver, kidneys, gills, blood, skin and carcass were examined individually. At the end of the accumulation phase between 0.63% (PFOA) and 15.5% (PFOS) of the absolute, applied quantity of PFAAs was recovered in the whole fish. The main target organ was the liver with recovery rates between 0.11% (PFBS) and 4.01% (PFOS) of the total amount of ingested PFAAs. Perfluoroalkyl sulfonic acids were taken up more readily and had longer estimated elimination half-lives than perfluoroalkyl carboxylic acids of the same chain length. The longest estimated elimination half-lives were found to be for PFOS between 8.4d in muscle tissue and 20.4d in the liver and for PFNA between 8.2d in the blood and 11.6d in the liver. PMID:25022474

Falk, Sandy; Failing, Klaus; Georgii, Sebastian; Brunn, Hubertus; Stahl, Thorsten

2015-06-01

111

Serum Cholesterol  

Microsoft Academic Search

The relationship between low serum cholesterol and albumin levels were examined to determine if serum cholesterol would be useful in screening for protein-calorie malnutrition (PCM). Audits were conducted retrospectively of 80 randomly selected hospitalized patients over 60 years of age, on various forms of oral and parenteral nutrition. The study sample consisted of acutely ill patients with delayed oral intake

L. A. Zarny; L. H. Bernstein

1995-01-01

112

Direct and simultaneous quantitation of 5-aminolaevulinic acid and porphobilinogen in human serum or plasma by hydrophilic interaction liquid chromatography-atmospheric pressure chemical ionization/tandem mass spectrometry.  

PubMed

Serum/plasma concentrations of 5-aminolaevulinic acid (ALA) and porphobilinogen (PBG) are elevated in patients with acute hepatic porphyrias, especially during acute attacks. Current assays require lengthy sample pre-treatment and derivatization steps. We report here a rapid, sensitive and specific hydrophilic interaction liquid chromatography-tandem mass spectrometry method for the direct and simultaneous quantitation of ALA and PBG in serum or plasma following simple protein precipitation with acetonitrile and centrifugation prior to injection. ALA and PBG were detected using selected reaction monitoring mode, following positive atmospheric pressure chemical ionization. Calibration was linear from 0.05 to 50 µmol/L for ALA and PBG. For both analytes, imprecision (relative standard deviation) was <13% and accuracy (percentage nominal concentrations) was between 92 and 107%. The method was successfully applied to the measurement of ALA and PBG in serum or plasma samples for the screening, biochemical diagnosis and treatment monitoring of patients with acute hepatic porphyrias. PMID:23180457

Benton, Christopher M; Couchman, Lewis; Marsden, Joanne T; Rees, David C; Moniz, Caje; Lim, Chang Kee

2013-02-01

113

Perfluoroalkyl acids (PFAAs) with isomer analysis in the commercial PFOS and PFOA products in China.  

PubMed

Perfluoroalkyl acids (PFAAs) have been widely used in consumer and industrial products for decades and are widely detected in the environment and humans all over the world. The information on the isomeric profiles of commercial products is important to identify the manufacturing origins of PFAAs in the environment. For the first time, the PFAA compositions and isomeric profiles of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) were reported in three PFOS and five PFOA commercial products manufactured in China. The purity of the three PFOS products was 76.7-80.6%. The major impurity in the PFOS products is PFOA, which contributes more than 10%. Other impurities include perfluorohexanesulfonate (PFHxS), perfluorohexanoate (PFHxA) and perfluoroheptanoate acids (PFHpA). The percentage of linear PFOS (n-PFOS) in the three products was 66.2-71.9%, similar to that in the product manufactured by 3M (70.3%). The purity of the five PFOA products was relatively high (94.0-95.8%), and the major impurity was PFOS (2.06-3.09%). The percentage of n-PFOA in the five PFOA products was 76.4-77.9%, which was similar to that in the 3M PFOA (78%). Although it is widely accepted that telomerization is currently the predominant manufacturing method for PFOA, yielding an isomerically pure and linear product, the results in the present study suggest that electrochemical fluorination is still used by some manufacturers in China. PMID:25703780

Jiang, Weiwei; Zhang, Yifeng; Yang, Liping; Chu, Xiaolong; Zhu, Lingyan

2015-05-01

114

Perfluoroalkyl substance contamination of the Llobregat River ecosystem (Mediterranean area, NE Spain).  

PubMed

The occurrence and sources of 21 perfluoroalkyl substances (PFASs: C4-C14, C16, C18 carboxylate, C4, C6-C8 and C10 sulfonates and C8 sulfonamide) were determined in water, sediment, and biota of the Llobregat River basin (NE Spain). Analytes were extracted by solid phase extraction (SPE) and determined by liquid chromatography triple quadrupole mass spectrometer (LC-QqQ-MS). All samples were contaminated with at least one PFAS, being the most frequently found perfluorobutanoate (PFBA), perfluorooctanoate (PFOA) and perfluorooctane sulfonate (L-PFOS). In general, mean PFAS concentrations measured in sediments (0.01-3.67 ng g(-1)) and biota (0.79-431 ?g kg(-1)) samples were higher than those found in water (0.01-233 ng L(-1)). L-PFOS presented very high levels in biota and water, particularly in the Anoia River where a maximum concentration of 2.71 ?g L(-1) was related to important industrial activities. However, this pollution does not extend down the Llobregat River according to cumulated values. None of the hazard quotients (HQ) calculated indicate potential risk for the different tropic levels considered (algae, Daphnia sp. and fish). According to Maximum Allowable Concentration (MAC) proposed by the European Commission (L-PFOS) and to Provisional Health Advisory (PHA) values (PFOA, L-PFOS) established by the United States Environmental Protection Agency (US EPA), only two water samples exceeded PHA concentration for L-PFOS. PMID:24935262

Campo, Julian; Pérez, Francisca; Masiá, Ana; Picó, Yolanda; Farré, Marinel la; Barceló, Damiŕ

2015-01-15

115

A review of sources, multimedia distribution and health risks of perfluoroalkyl acids (PFAAs) in China.  

PubMed

Perfluoroalkyl acids (PFAAs) have been recognized as emerging pollutants because of their ubiquitous occurrence in the environment, biota and humans. In order to investigate their sources, fate and environmental effects, a great number of surveys have been carried out over the past several years. In the present review, we summarized the status of sources and emission, concentration, distribution and risks of PFAAs in China. Concentrations of PFAAs, especially perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in various environmental media including water, sediment, soil, rain, snow and organisms, as well as human tissues are summarized based on the available data. Concentrations of PFAAs in aquatic systems are higher in relatively more industrialized and urbanized areas than those from the less populated and remote regions in China, indicating that their emission and distribution are closely related to regional urbanization and industrialization. PFAAs and related products have been widely used over the past several decades, which have brought about high concentrations detected in environmental matrixes, biota and even local residents. Ecological risk assessment of PFAAs is still less developed in China. Most existing studies compared concentrations of PFAAs to guideline values derived for single species to evaluate the risk. In order to reveal the transport, partitioning and degradation of PFAAs in the environment, further studies on their behavior, fate, bioaccumulation and adverse effects in different trophic levels should be conducted. PMID:25262946

Wang, Tieyu; Wang, Pei; Meng, Jing; Liu, Shijie; Lu, Yonglong; Khim, Jong Seong; Giesy, John P

2015-06-01

116

Perfluoroalkyl substances in soils around the Nepali Koshi River: levels, distribution, and mass balance.  

PubMed

Perfluoroalkyl substances (PFASs) were analyzed in surface soils along the Koshi River in Nepal, a typical agricultural country with little industrialization and urbanization. Sixteen target PFASs were quantified in soils from a hilly region in central and eastern Nepal, but only ten PFASs were detected. Concentrations of total PFASs ranged from nd (below the detection limit) to 1.78 ng/g dw. The predominant PFASs in soils were perfluoro-octanoic acid (PFOA) and perfluoro-butanesulfonate (PFBS) with concentrations that ranged from nd to 0.26 ng/g dw and nd to 0.38 ng/g dw, respectively. Results of mass balance analysis also revealed weak associations among concentrations of PFASs, extractable organic fluorine (EOF), and total fluorine (TF). PFASs were relatively evenly distributed among locations. Due to the absence of direct emission of PFASs and slow development of local industry, PFASs in soils originated mostly from long-range atmospheric transport, consumer use, and disposal of PFASs-containing products. Uncontrolled disposal of domestic waste will be a challenge to controlling concentrations of PFASs in Nepal. PMID:24705951

Tan, Bing; Wang, Tieyu; Wang, Pei; Luo, Wei; Lu, Yonglong; Romesh, Kumar Y; Giesy, John P

2014-08-01

117

Perfluoroalkyl substances and organochlorine pesticides in sediments from Huaihe watershed in China.  

PubMed

Twelve perfluoroalkyl substances (PFASs) and nine organochlorine pesticides (OCPs) were quantified in surface sediments from the Huaihe River, China, along which there are intensive industrial and agricultural activities. Concentrations of PFASs ranged from 0.06 to 0.46ng/g dry weight (dw), and concentrations of OCPs ranged from 1.48 to 32.65ng/gdw. Compared with other areas in China, concentrations of PFASs were lesser than the national mean value, while concentrations of OCPs were moderate. Concentrations of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) ranged from n.d. (not detected) to 0.03 and n.d. to 0.10ng/gdw, respectively. Among the three groups of OCPs, mean concentrations of hexachlorocyclohexane and its isomers (HCHs), dichlorodiphenyltrichloroethane and its metabolites (DDTs) and hexachlorobenzene (HCB) were 5.62±4.35, 2.43±3.12 and 1.55±4.17ng/gdw, respectively. Concentrations of HCHs and DDTs decreased from upstream to downstream along the mainstream of the Huaihe River. When compared to sediment quality guidelines (SQGs), concentrations of HCHs, DDTs and HCB would pose adverse biological effects. In general, contamination by PFASs in the upstream of the Huaihe River was more severe than that in the downstream, which was mainly caused by interception from dams, locks and industrial emissions. And OCPs from tributaries, especially the Yinghe River and Wohe River, were higher than those from Huaihe mainstream, and primarily came from historical inputs. PMID:25458673

Meng, Jing; Wang, Tieyu; Wang, Pei; Giesy, John P; Lu, Yonglong

2014-11-01

118

Spatial distribution of perfluoroalkyl acids in surface sediments of the German Bight, North Sea.  

PubMed

Perfluoroalkyl acids (PFAAs) have been determined in the environment globally. However, studies on the occurrence of PFAAs in marine sediment remain limited. In this study, 16 PFAAs are investigated in surface sediments from the German Bight, which provided a good overview of the spatial distribution. The concentrations of ?PFAAs ranged from 0.056 to 7.4ng/g dry weight. The highest concentration was found at the estuary of the River Ems, which might be the result of local discharge source. Perfluorooctane sulfonic acid (PFOS) was the dominant compound, and the enrichment of PFOS in sediment might be strongly related to the compound structure itself. The geographical condition of the German Bight influenced the movement of water and sediment, resulting in complex distribution. Following normalization according to total organic carbon (TOC) content, PFAA distributions showed a different picture. Significant linear relationships were found between total PFAA concentrations and TOC (R(2)=0.50, p<0.01). Compared with a previous study conducted in the same area, a declining trend was presented for the concentrations of PFOS and perfluorooctanoic acid (PFOA). Compound structure, geographical condition, and organic carbon in the sediment influence the distribution of PFAAs in the German Bight. Environmental risk assessment indicated that the risk from PFOA is negligible, whereas PFOS in marine sediment may present a risk for benthic organisms in the German Bight. PMID:25544333

Zhao, Zhen; Xie, Zhiyong; Tang, Jianhui; Zhang, Gan; Ebinghaus, Ralf

2015-04-01

119

Alternative eluent composition for LC-MS analysis of perfluoroalkyl acids in raw fish samples.  

PubMed

A wide range of anthropogenic pollutants that possess serious environmental and health risks are known. One type of these harmful substances that have become a focus of interest during the past decade are perfluoroalkyl acids (PFAAs), which are extensively used in industry for different purposes. Due to the harmful effects that these compounds might cause in living organisms, EFSA and EU CONTAM panel have issued a monitoring program for PFAAs in foodstuffs. This has given rise to intense research dedicated to the analysis of PFAAs over the past few years. This work focuses on chromatographic analysis of three PFAAs in fish. The analytes, perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorooctanesulfonic acid (PFOS), are commonly associated with the production of fluoropolymers. Fluorinated alcohols are used as eluent components, and their possible advantages as eluent modifiers in LC-MS analysis of PFAAs, alternative retention mechanism and enhanced ionization efficiency, are examined. The analyzed fish samples originating from Estonian fresh and marine waters had low contents of PFAAs. PMID:24845542

Haljasorg, Tőiv; Saame, Jaan; Kipper, Karin; Teearu, Anu; Herodes, Koit; Reinik, Mari; Leito, Ivo

2014-06-11

120

Temporal variations of perfluoroalkyl substances and polybrominated diphenyl ethers in alpine snow.  

PubMed

The occurrence and temporal variation of 18 perfluoroalkyl substances (PFASs) and 8 polybrominated diphenyl ethers (PBDEs) in the European Alps was investigated in a 10 m shallow firn core from Colle Gnifetti in the Monte Rosa Massif (4455 m above sea level). The firn core encompasses the years 1997-2007. Firn core sections were analyzed by liquid chromatography-tandem mass spectrometry (PFASs) and gas chromatography-mass spectrometry (PBDEs). We detected 12 PFASs and 8 PBDEs in the firn samples. Perfluorobutanoic acid (PFBA; 0.3-1.8 ng L(-1)) and perfluorooctanoic acid (PFOA; 0.2-0.6 ng L(-1)) were the major PFASs while BDE 99 (

Kirchgeorg, Torben; Dreyer, Annekatrin; Gabrieli, Jacopo; Kehrwald, Natalie; Sigl, Michael; Schwikowski, Margit; Boutron, Claude; Gambaro, Andrea; Barbante, Carlo; Ebinghaus, Ralf

2013-07-01

121

Neutral Poly-/perfluoroalkyl Substances in Air and Snow from the Arctic  

PubMed Central

Levels of neutral poly-/perfluoroalkyl substances (nPFASs) in air and snow collected from Ny-Ĺlesund were measured and their air-snow exchange was determined to investigate whether they could re-volatilize into the atmosphere driven by means of air-snow exchange. The total concentration of 12 neutral PFASs ranged from 6.7 to 39?pg m?3 in air and from 330 to 690?pg L?1 in snow. A significant log-linear relationship was observed between the gas/particle partition coefficient and vapor pressure of the neutral PFASs. For fluorotelomer alcohol (FTOHs) and fluorotelomer acrylates (FTAs), the air-snow exchange fluxes were positive, indicating net evaporative from snow into air, while net deposition into snow was observed for perfluorooctane sulfonamidoethanols (Me/EtFOSEs) in winter and spring of 2012. The air-snow exchange was snow-phase controlled for FTOHs and FTAs, and controlled by the air-phase for FOSEs. Air-snow exchange may significantly interfere with atmospheric concentrations of neutral PFASs in the Arctic. PMID:25746440

Xie, Zhiyong; Wang, Zhen; Mi, Wenying; Möller, Axel; Wolschke, Hendrik; Ebinghaus, Ralf

2015-01-01

122

Perfluoroalkyl contaminants in plasma of five sea turtle species: comparisons in concentration and potential health risks.  

PubMed

The authors compared blood plasma concentrations of 13 perfluoroalkyl contaminants (PFCs) in five sea turtle species with differing trophic levels. Wild sea turtles were blood sampled from the southeastern region of the United States, and plasma was analyzed using liquid chromatography tandem mass spectrometry. Mean concentrations of perfluorooctane sulfonate (PFOS), the predominant PFC, increased with trophic level from herbivorous greens (2.41 ng/g), jellyfish-eating leatherbacks (3.95 ng/g), omnivorous loggerheads (6.47 ng/g), to crab-eating Kemp's ridleys (15.7 ng/g). However, spongivorous hawksbills had surprisingly high concentrations of PFOS (11.9 ng/g) and other PFCs based on their trophic level. These baseline concentrations of biomagnifying PFCs demonstrate interesting species and geographical differences. The measured PFOS concentrations were compared with concentrations known to cause toxic effects in laboratory animals, and estimated margins of safety (EMOS) were calculated. Small EMOS (<100), suggestive of potential risk of adverse health effects, were observed for all five sea turtle species for immunosuppression. Estimated margins of safety less than 100 were also observed for liver, thyroid, and neurobehavorial effects for the more highly exposed species. These baseline concentrations and the preliminary EMOS exercise provide a better understanding of the potential health risks of PFCs for conservation managers to protect these threatened and endangered species. PMID:22447337

Keller, Jennifer M; Ngai, Lily; Braun McNeill, Joanne; Wood, Lawrence D; Stewart, Kelly R; O'Connell, Steven G; Kucklick, John R

2012-06-01

123

Structure-activity relations in binding of perfluoroalkyl compounds to human thyroid hormone T3 receptor.  

PubMed

Perfluoroalkyl compounds (PFCs) have been shown to disrupt thyroid functions through thyroid hormone receptor (TR)-mediated pathways, but direct binding of PFCs with TR has not been demonstrated. We investigated the binding interactions of 16 structurally diverse PFCs with human TR, their activities on TR in cells, and the activity of perfluorooctane sulfonate (PFOS) in vivo. In fluorescence competitive binding assays, most of the 16 PFCs were found to bind to TR with relative binding potency in the range of 0.0003-0.05 compared with triiodothyronine (T3). A structure-binding relationship for PFCs was observed, where fluorinated alkyl chain length longer than ten, and an acid end group were optimal for TR binding. In thyroid hormone (TH)-responsive cell proliferation assays, PFOS, perfluorohexadecanoic acid, and perfluorooctadecanoic acid exhibited agonistic activity by promoting cell growth. Furthermore, similar to T3, PFOS exposure promoted expression of three TH upregulated genes and inhibited three TH downregulated genes in amphibians. Molecular docking analysis revealed that most of the tested PFCs efficiently fit into the T3-binding pocket in TR and formed a hydrogen bond with arginine 228 in a manner similar to T3. The combined in vitro, in vivo, and computational data strongly suggest that some PFCs disrupt the normal activity of TR pathways by directly binding to TR. PMID:24819616

Ren, Xiao-Min; Zhang, Yin-Feng; Guo, Liang-Hong; Qin, Zhan-Fen; Lv, Qi-Yan; Zhang, Lian-Ying

2015-02-01

124

Neutral Poly-/perfluoroalkyl Substances in Air and Snow from the Arctic  

NASA Astrophysics Data System (ADS)

Levels of neutral poly-/perfluoroalkyl substances (nPFASs) in air and snow collected from Ny-Ĺlesund were measured and their air-snow exchange was determined to investigate whether they could re-volatilize into the atmosphere driven by means of air-snow exchange. The total concentration of 12 neutral PFASs ranged from 6.7 to 39 pg m-3 in air and from 330 to 690 pg L-1 in snow. A significant log-linear relationship was observed between the gas/particle partition coefficient and vapor pressure of the neutral PFASs. For fluorotelomer alcohol (FTOHs) and fluorotelomer acrylates (FTAs), the air-snow exchange fluxes were positive, indicating net evaporative from snow into air, while net deposition into snow was observed for perfluorooctane sulfonamidoethanols (Me/EtFOSEs) in winter and spring of 2012. The air-snow exchange was snow-phase controlled for FTOHs and FTAs, and controlled by the air-phase for FOSEs. Air-snow exchange may significantly interfere with atmospheric concentrations of neutral PFASs in the Arctic.

Xie, Zhiyong; Wang, Zhen; Mi, Wenying; Möller, Axel; Wolschke, Hendrik; Ebinghaus, Ralf

2015-03-01

125

Bioaccumulation characteristics of perfluoroalkyl acids (PFAAs) in coastal organisms from the west coast of South Korea.  

PubMed

Year-round monitoring for perfluoroalkyl acids (PFAAs) along the west coast of South Korea targeting long-term changes in water and coastal organisms has been conducted since 2008. In this study, we present the most recent 5-years of accumulated data and scrutinize the relationship between concentrations in water and biota highlighting bioaccumulation characteristics. Twelve individual PFAAs in samples of water (n=43) and biota (n=59) were quantified by use of HPLC-MS/MS after solid phase extraction. In recent years, concentrations of PFAAs in water have been generally decreasing, but profiles of relative concentrations of individual PFAAs vary among location and year. Bioaccumulation of PFAAs in various organisms including fishes, bivalves, crabs, gastropods, shrimps, starfish, and polychaetes varied among species. However, overall bioaccumulation of PFAAs was dependent on corresponding concentrations of PFAAs in water within an area. In organ-specific distributions of PFAAs, greater concentrations of PFAAs were found in intestine of fish (green eel goby). This result suggests that PFAAs are mainly accumulated via dietary exposure, while greater concentrations were found in gill and intestine of bivalve (oyster) which suggests both waterborne and dietary exposures to these organisms. Concentrations of PFAAs in biota did not decrease over time (2008-2010), indicating that continuing bioaccumulation followed by slow degradation or excretion of PFAAs accumulated in biota. Overall, spatio-temporal distributions of PFAAs in water and bioaccumulation characteristics seemed to be associated with recent restrictions of PFOS-based products and uses of PFBS-based substitutes. PMID:25015225

Hong, Seongjin; Khim, Jong Seong; Wang, Tieyu; Naile, Jonathan E; Park, Jinsoon; Kwon, Bong-Oh; Song, Sung Joon; Ryu, Jongseong; Codling, Garry; Jones, Paul D; Lu, Yonglong; Giesy, John P

2015-06-01

126

Neutral Poly-/perfluoroalkyl Substances in Air and Snow from the Arctic.  

PubMed

Levels of neutral poly-/perfluoroalkyl substances (nPFASs) in air and snow collected from Ny-Ĺlesund were measured and their air-snow exchange was determined to investigate whether they could re-volatilize into the atmosphere driven by means of air-snow exchange. The total concentration of 12 neutral PFASs ranged from 6.7 to 39?pg m(-3) in air and from 330 to 690?pg L(-1) in snow. A significant log-linear relationship was observed between the gas/particle partition coefficient and vapor pressure of the neutral PFASs. For fluorotelomer alcohol (FTOHs) and fluorotelomer acrylates (FTAs), the air-snow exchange fluxes were positive, indicating net evaporative from snow into air, while net deposition into snow was observed for perfluorooctane sulfonamidoethanols (Me/EtFOSEs) in winter and spring of 2012. The air-snow exchange was snow-phase controlled for FTOHs and FTAs, and controlled by the air-phase for FOSEs. Air-snow exchange may significantly interfere with atmospheric concentrations of neutral PFASs in the Arctic. PMID:25746440

Xie, Zhiyong; Wang, Zhen; Mi, Wenying; Möller, Axel; Wolschke, Hendrik; Ebinghaus, Ralf

2015-01-01

127

Investigation of the excited state iodine lifetime in the photodissociation of perfluoroalkyl iodides  

NASA Technical Reports Server (NTRS)

An evaluation of prospective laser materials for a space-based solar pumped laser system over the past decade has resulted in the identification of the iodine photodissociation laser as that system best suited to solar-pumped high energy operation. The active medium for the solar-pumped iodine photodissociation laser is from the family of perfluoroalkyl iodides. These lasants have the general form C(n)F(2n + 1)I, often abbreviated as RI. These iodides are known to exhibit photodissociaiton of the C-I bond when irradiated by near UV photons. The focus was on the experimental determination of the lifetime of the excited iodine atom following photodissociation of C4F9I, and also to monitor fluorescence from the iodine molecule at 500 nm to determine if I2 is being produced in the process. Photodissociation is achieved using an XeCl excimer laser with an output wavelength of 308 nm. The XeCl beam is focused into the middle of a cylindrical quartz cell containing the lasant. The laser pulse is detected with a fast risetime photomultiplier tube as it exits the cell. Other aspects of the investigation are discussed.

Cobb, Stephen H.

1991-01-01

128

Exposure and effects of perfluoroalkyl substances in tree swallows nesting in Minnesota and Wisconsin, USA.  

PubMed

The exposure and effects of perfluoroalkyl substances (PFASs) were studied at eight locations in Minnesota and Wisconsin between 2007 and 2011 using tree swallows (Tachycineta bicolor). Concentrations of PFASs were quantified as were reproductive success end points. The sample egg method was used wherein an egg sample is collected, and the hatching success of the remaining eggs in the nest is assessed. The association between PFAS exposure and reproductive success was assessed by site comparisons, logistic regression analysis, and multistate modeling, a technique not previously used in this context. There was a negative association between concentrations of perfluorooctane sulfonate (PFOS) in eggs and hatching success. The concentration at which effects became evident (150-200 ng/g wet weight) was far lower than effect levels found in laboratory feeding trials or egg-injection studies of other avian species. This discrepancy was likely because behavioral effects and other extrinsic factors are not accounted for in these laboratory studies and the possibility that tree swallows are unusually sensitive to PFASs. The results from multistate modeling and simple logistic regression analyses were nearly identical. Multistate modeling provides a better method to examine possible effects of additional covariates and assessment of models using Akaike information criteria analyses. There was a credible association between PFOS concentrations in plasma and eggs, so extrapolation between these two commonly sampled tissues can be performed. PMID:23860575

Custer, Christine M; Custer, Thomas W; Dummer, Paul M; Etterson, Matthew A; Thogmartin, Wayne E; Wu, Qian; Kannan, Kurunthachalam; Trowbridge, Annette; McKann, Patrick C

2014-01-01

129

Partition of perfluoroalkyl substances (PFASs) in whole blood and plasma, assessed in maternal and umbilical cord samples from inhabitants of arctic Russia and Uzbekistan.  

PubMed

Perfluoroalkyl substances (PFASs) are ubiquitous in the environment world-wide. Our overall objective was to assess the exposure to PFASs experienced by delivering women and their new-borns in the industrial city of Norilsk (arctic Russia) and the rural Aral Sea region of Uzbekistan, with the secondary objective of evaluating the distribution of PFASs between blood cell and plasma fractions. Six PFASs were detected in every sample from Norilsk city with the plasma concentration sequence of: PFOS?PFOA>PFNA>FOSA>PFHxS>PFUnDA. In the Uzbekistani samples, only PFOS was reported above the MDL (0.08 ng/mL). The median plasma concentrations of PFOS of 11.0 ng/mL for the Norilsk mothers was comparable to that reported for western countries, while that for Uzbekistan was considerably lower (0.23 ng/mL). Apparent increases in the maternal-cord concentration ratios for both whole blood and plasma were evident with the length of the carbon chain for both the carboxylate and the sulfonate PFASs. The median value of this ratio for FOSA in plasma was the lowest, while that for whole blood was the highest. Other than for FOSA, the observed plasma-whole blood concentration ratios for maternal and umbilical cord blood were consistent with a priori calculations using appropriate packed cell and plasma volumes for neonates and pregnant women at term. Clearly FOSA favored whole blood, and acid-base equilibrium calculations suggested that the resonance-stabilized sulfonamidate ion resides in the blood cell fraction. Thus for PFASs and related compounds with pK values with magnitudes comparable to physiological pH, it is pertinent to measure the cell-associated fraction (separately or as whole blood). Our study illustrates that consideration of both the physico-chemical properties of the contaminants and the physiological attributes of blood matrices were helpful in the interpretation of our findings. PMID:23410865

Hanssen, Linda; Dudarev, Alexey A; Huber, Sandra; Odland, Jon Řyvind; Nieboer, Evert; Sandanger, Torkjel M

2013-03-01

130

High levels of perfluoroalkyl acids in sport fish species downstream of a firefighting training facility at Hamilton International Airport, Ontario, Canada.  

PubMed

A recent study reported elevated concentrations of perfluorooctane sulfonic acid (PFOS) and other perfluoroalkyl acids (PFAAs) in surface water, snapping turtles, and amphipods in Lake Niapenco, downstream of Hamilton International Airport, Ontario, Canada. Here, our goals were to 1) determine the extent of PFAA contamination in sport fish species collected downstream of the airport, 2) explore if the airport could be a potential source, and 3) compare fish PFOS concentrations to consumption advisory benchmarks. The PFOS levels in several sport fish collected from the three locations closest to the airport (<40km) were among the highest previously published in the peer-reviewed literature and also tended to exceed consumption benchmarks. The only other fish that had comparable concentrations were collected in a region affected by inputs from a major fluorinated chemical production facility. In contrast, PFOS concentrations in the two most downstream locations (>70km) were comparable to or below the average concentrations in fish as observed in the literature and were generally below the benchmarks. With regards to perfluorocarboxylates (PFCAs), there was no significant decrease in concentrations in fish with distance from the airport and levels were comparable to or below the average concentrations observed in the literature, suggesting that the airport is not a significant source of PFCAs in these fish species. PFOS-based aqueous film-forming foam (AFFF) was used at a firefighting training facility at the airport in the 1980s to mid-1990s. Taken together, our results provide evidence that the historical use of AFFF at the airport has resulted in fish PFOS concentrations that exceed the 95th percentile concentration of values reported in the literature to date. PMID:24632327

Gewurtz, Sarah B; Bhavsar, Satyendra P; Petro, Steve; Mahon, Chris G; Zhao, Xiaoming; Morse, Dave; Reiner, Eric J; Tittlemier, Sheryl A; Braekevelt, Eric; Drouillard, Ken

2014-06-01

131

Perfluoroalkyl sulfonic and carboxylic acids: A critical review of physicochemical properties, levels and patterns in waters and wastewaters, and treatment methods  

Microsoft Academic Search

Perfluorinated acids (PFAs) are an emerging class of environmental contaminants present in various environmental and biological matrices. Two major PFA subclasses are the perfluorinated sulfonic acids (PFSAs) and carboxylic acids (PFCAs). The physicochemical properties and partitioning behavior for the linear PFA members are poorly understood and widely debated. Even less is known about the numerous branched congeners with varying perfluoroalkyl

Sierra Rayne; Kaya Forest

2009-01-01

132

Evaluation of additivity of binary mixtures of perfluoroalkyl acids (PFAAs) on peroxisome proliferator-activated receptor-alpha (PPARa) activation in vitro  

EPA Science Inventory

Perfluoroalkyl acids (PFAAs) are found globally in the environment and in animal tissues, and are present as mixtures of PFAA congeners. Mechanistic studies have found that in vivo effects of PFAAs are mediated by PPARL. Our previous studies showed that individual PFAAs activate ...

133

Distribution, source characterization and inventory of perfluoroalkyl substances in Taihu Lake, China.  

PubMed

The levels, distribution, possible sources, and inventory of perfluoroalkyl acids (PFAAs) in the eutrophic freshwater Taihu Lake, East China were investigated in this study. Among the target 11 PFAAs, perfluorooctanoic acid (PFOA) (2.15-73.9ngL(-1)) and perfluorohexanoic acid (PFHxA) (

Guo, Changsheng; Zhang, Yuan; Zhao, Xin; Du, Ping; Liu, Sisi; Lv, Jiapei; Xu, Fengxia; Meng, Wei; Xu, Jian

2015-05-01

134

Circulating Mitochondrial DNA as Biomarker Linking Environmental Chemical Exposure to Early Preclinical Lesions Elevation of mtDNA in Human Serum after Exposure to Carcinogenic Halo-Alkane-Based Pesticides  

PubMed Central

There is a need for a panel of suitable biomarkers for detection of environmental chemical exposure leading to the initiation or progression of degenerative diseases or potentially, to cancer. As the peripheral blood may contain increased levels of circulating cell-free DNA in diseased individuals, we aimed to evaluate this DNA as effect biomarker recognizing vulnerability after exposure to environmental chemicals. We recruited 164 individuals presumably exposed to halo-alkane-based pesticides. Exposure evaluation was based on human biomonitoring analysis; as biomarker of exposure parent halo-methanes, -ethanes and their metabolites, as well as the hemoglobin-adducts methyl valine and hydroxyl ethyl valine in blood were used, complemented by expert evaluation of exposure and clinical intoxication symptoms as well as a questionnaire. Assessment showed exposures to halo alkanes in the concentration range being higher than non-cancer reference doses (RfD) but (mostly) lower than the occupational exposure limits. We quantified circulating DNA in serum from 86 individuals with confirmed exposure to off-gassing halo-alkane pesticides (in storage facilities or in home environment) and 30 non-exposed controls, and found that exposure was significantly associated with elevated serum levels of circulating mitochondrial DNA (in size of 79 bp, mtDNA-79, p?=?0.0001). The decreased integrity of mtDNA (mtDNA-230/mtDNA-79) in exposed individuals implicates apoptotic processes (p?=?0.015). The relative amounts of mtDNA-79 in serum were positively associated with the lag-time after intoxication to these chemicals (r?=?0.99, p<0.0001). Several months of post-exposure the specificity of this biomarker increased from 30% to 97% in patients with intoxication symptoms. Our findings indicate that mitochondrial DNA has a potential to serve as a biomarker recognizing vulnerable risk groups after exposure to toxic/carcinogenic chemicals. PMID:23741329

Budnik, Lygia T.; Kloth, Stefan; Baur, Xaver; Preisser, Alexandra M.; Schwarzenbach, Heidi

2013-01-01

135

Determinants of plasma concentrations of perfluoroalkyl substances in pregnant Norwegian women  

PubMed Central

Background Perfluoroalkyl substances (PFASs) are widespread pollutants that have been associated with adverse health effects although not on a consistent basis. Diet has been considered the main source of exposure. The aim of the present study was to identify determinants of four plasma PFASs in pregnant Norwegian women. Methods This study is based in the Norwegian Mother and Child Cohort Study (MoBa) conducted by the Norwegian Institute of Public Health. Our sample included 487 women who enrolled in MoBa from 2003–2004. A questionnaire regarding sociodemographic, medical, and reproductive history was completed at 17 weeks gestation and a dietary questionnaire was completed at 22 weeks gestation. Maternal plasma samples were obtained around 17 weeks of gestation. Plasma concentrations of four PFASs (perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorohexane sulfonate (PFHxS), and perfluorononanoate (PFNA)) were examined in relation to demographic, lifestyle, dietary, and pregnancy-related covariates. Predictors were identified by optimizing multiple linear regression models using Akaike’s information criterion (AIC). Results Parity was the determinant with the largest influence on plasma PFAS concentrations, with r2 between 0.09 and 0.32 in simple regression models. In optimal multivariate models, when compared to nulliparous women, parous women had 46%, 70%, 19%, and 62% lower concentrations of PFOS, PFOA, PFHxS, and PFNA respectively (p<0.001 except for PFHxS, p<0.01). In all these models, duration of breastfeeding was associated with reduced PFAS levels. PFOA showed the largest reduction from breastfeeding, with a 2–3% reduction per month of breastfeeding in typical cases. Levels of PFOS, PFOA, and PFNA increased with time since most recent pregnancy. While pregnancy-related factors were the most important predictors, diet was a significant factor explaining up to 4% of the variance. One quartile increase in estimated dietary PFAS intake was associated with plasma PFOS, PFOA, PFHxS, and PFNA concentration increases of 7.2%, 3.3%, 5.8% and 9.8%, respectively, resulting in small, although non-trivial absolute changes in PFAS concentrations. Conclusion The history of previous pregnancies and breastfeeding were the most important determinants of PFASs in this sample of pregnant women. PMID:23419425

Whitworth, KW; Ydersbond, TA; Haug, LS; Haugen, M; Knutsen, HK; Thomsen, C; Meltzer, HM; Becher, G; Sabaredzovic, A; Hoppin, JA; Eggesbř, M; Longnecker, MP

2013-01-01

136

Perfluoroalkyl acids in the Canadian environment: multi-media assessment of current status and trends.  

PubMed

In Canada, perfluoroalkyl acids (PFAAs) have been the focus of several monitoring programs and research and surveillance studies. Here, we integrate recent data and perform a multi-media assessment to examine the current status and ongoing trends of PFAAs in Canada. Concentrations of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and other long-chain perfluorocarboxylates (PFCAs) in air, water, sediment, fish, and birds across Canada are generally related to urbanization, with elevated concentrations observed around cities, especially in southern Ontario. PFOS levels in water, fish tissue, and bird eggs were below their respective Draft Federal Environmental Quality Guidelines, suggesting there is low potential for adverse effects to the environment/organisms examined. However, PFOS in fish and bird eggs tended to exceed guidelines for the protection of mammalian and avian consumers, suggesting a potential risk to their wildlife predators, although wildlife population health assessments are needed to determine whether negative impacts are actually occurring. Long-term temporal trends of PFOS in suspended sediment, sediment cores, Lake Trout (Salvelinus namaycush), and Herring Gull (Larus argentatus) eggs collected from Lake Ontario increased consistently from the start of data collection until the 1990s. However, after this time, the trends varied by media, with concentrations stabilizing in Lake Trout and Herring Gull eggs, and decreasing and increasing in suspended sediment and the sediment cores, respectively. For PFCAs, concentrations in suspended sediment, sediment cores, and Herring Gulls generally increased from the start of data collection until present and concentrations in Lake Trout increased until the late 1990s and subsequently stabilized. A multimedia comparison of PFAA profiles provided evidence that unexpected patterns in biota of some of the lakes were due to unique source patterns rather than internal lake processes. High concentrations of PFAAs in the leachate and air of landfill sites, in the wastewater influent/effluent, biosolids, and air at wastewater treatment plants, and in indoor air and dust highlight the waste sector and current-use products (used primarily indoors) as ongoing sources of PFAAs to the Canadian environment. The results of this study demonstrate the utility of integrating data from different media. Simultaneous evaluation of spatial and temporal trends in multiple media allows inferences that would be impossible with data on only one medium. As such, more co-ordination among monitoring sites for different media is suggested for future sampling, especially at the northern sites. We emphasize the importance of continued monitoring of multiple-media for determining future responses of environmental PFAA concentrations to voluntary and regulatory actions. PMID:23831544

Gewurtz, Sarah B; Backus, Sean M; De Silva, Amila O; Ahrens, Lutz; Armellin, Alain; Evans, Marlene; Fraser, Susan; Gledhill, Melissa; Guerra, Paula; Harner, Tom; Helm, Paul A; Hung, Hayley; Khera, Nav; Kim, Min Gu; King, Martha; Lee, Sum Chi; Letcher, Robert J; Martin, Pamela; Marvin, Chris; McGoldrick, Daryl J; Myers, Anne L; Pelletier, Magella; Pomeroy, Joe; Reiner, Eric J; Rondeau, Myriam; Sauve, Marie-Claude; Sekela, Mark; Shoeib, Mahiba; Smith, Daniel W; Smyth, Shirley Anne; Struger, John; Spry, Doug; Syrgiannis, Jim; Waltho, Jasmine

2013-09-01

137

Subsurface transport potential of perfluoroalkyl acids at aqueous film-forming foam (AFFF)-impacted sites.  

PubMed

Subsurface transport potential of a suite of perfluoroalkyl acids (PFAAs) was studied in batch sorption experiments with various soils and in the presence of co-contaminants relevant to aqueous film-forming foam (AFFF)-impacted sites. Specifically, PFAA sorption to multiple soils in the presence of nonaqueous phase liquid (NAPL) and nonfluorinated AFFF surfactants was examined. This study is the first to report on sorption of perfluorobutanoate (PFBA) and perfluoropentanoate (PFPeA) (log Koc = 1.88 and 1.37, respectively) and found that sorption of these compounds does not follow the chain-length dependent trend observed for longer chain-length PFAAs. Sorption of PFBA was similar to that of perfluorooctanoate (PFOA, log Koc = 1.89). NAPL and nonfluorinated AFFF surfactants all had varying impacts on sorption of longer chain (>6 CF2 groups) PFAAs. The primary impact of NAPL was observed in low foc soil (soil A) where Freundlich n-values increased when NAPL was present. Impacts of nonfluorinated AFFF surfactants varied with surfactant and soil. The anionic surfactant sodium decyl sulfate (SDS) illicited PFAA chain-length dependent impacts in two negatively charged soils with varying foc. In soil A, Kd values for perfluoroheptanoate (PFHpA) increased 91% with SDS, whereas values for perfluorodecanoate (PFDA) increased only 28%. An amphoteric surfactant, n,n-dimethyldodecylamine n-oxide (AO), had the most notable impact on PFAA sorption to a positively charged soil (soil C). In this soil, AO oxide significantly increased sorption for the longer chain PFAAs (i.e., 528% increase in Kd for PFDA). Changes in sorption caused by SDS and AO may be due to mixed hemimicelle formation, competitive sorption, or changes to PFAA solubility. Short-chain PFAA behavior in the presence of NAPL, SDS, and AO was again notable. Co-contaminants generally increased the sorption of these compounds to all soils. Log Kd values of PFBA in soil A increased 85%, 372%, and 32% in the presence of NAPL, SDS, and AO, respectively. Use of Kd values to calculate retardation factors (Rf) of PFAAs demonstrates the variability of co-contaminant impacts on PFAA transport. Whereas NAPL and nonfluorinated surfactants decreased the sorption of perfluorooctanesulfonate (PFOS) at lower PFOS concentrations (1 ?g/L), they led to increases in sorption at higher PFOS concentrations (500 ?g/L). These results demonstrate that PFAA groundwater transport will depend on the solid phase characteristics as well as PFAA concentration and chain length. Detailed site-specific information will likely be needed to accurately predict PFAA transport at AFFF-impacted sites. PMID:23566120

Guelfo, Jennifer L; Higgins, Christopher P

2013-05-01

138

Neutral poly- and perfluoroalkyl substances in air and seawater of the North Sea.  

PubMed

Concentrations of neutral poly- and perfluoroalkyl substances (PFASs), such as fluorotelomer alcohols (FTOHs), perfluoroalkane sulfonamides (FASAs), perfluoroalkane sufonamidoethanols (FASEs), and fluorotelomer acrylates (FTACs), have been simultaneously determined in surface seawater and the atmosphere of the North Sea. Seawater and air samples were taken aboard the German research vessel Heincke on the cruise 303 from 15 to 24 May 2009. The concentrations of FTOHs, FASAs, FASEs, and FTACs in the dissolved phase were 2.6-74, <0.1-19, <0.1-63, and <1.0-9.0 pg L(-1), respectively. The highest concentrations were determined in the estuary of the Weser and Elbe rivers and a decreasing concentration profile appeared with increasing distance from the coast toward the central part of the North Sea. Gaseous FTOHs, FASAs, FASEs, and FTACs were in the range of 36-126, 3.1-26, 3.7-19, and 0.8-5.6 pg m(-3), which were consistent with the concentrations determined in 2007 in the North Sea, and approximately five times lower than those reported for an urban area of Northern Germany. These results suggested continuous continental emissions of neutral PFASs followed by transport toward the marine environment. Air-seawater gas exchanges of neutral PFASs were estimated using fugacity ratios and the two-film resistance model based upon paired air-seawater concentrations and estimated Henry's law constant values. Volatilization dominated for all neutral PFASs in the North Sea. The air-seawater gas exchange fluxes were in the range of 2.5×10(3)-3.6×10(5) pg m(-2) for FTOHs, 1.8×10(2)-1.0×10(5) pg m(-2) for FASAs, 1.1×10(2)-3.0×10(5) pg m(-2) for FASEs and 6.3×10(2)-2.0×10(4) pg m(-2) for FTACs, respectively. These results suggest that the air-seawater gas exchange is an important process that intervenes in the transport and fate for neutral PFASs in the marine environment. PMID:23636599

Xie, Zhiyong; Zhao, Zhen; Möller, Axel; Wolschke, Hendrik; Ahrens, Lutz; Sturm, Renate; Ebinghaus, Ralf

2013-11-01

139

Association between thyroid profile and perfluoroalkyl acids: Data from NHNAES 2007–2008  

SciTech Connect

The effect of six perfluoroalkyl acids (PFAAs), namely, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorodecanoic acid (PFDE), perfluorohexane sulfonic acid (PFHxS), 2-(N-methyl-perfluorooctane sulfonamide) acetic acid (MPAH), and perfluorononanoic acid (PFNA) on the levels of six thyroid function variables, namely, thyroid stimulating hormone (TSH), free and total thyroxine (FT4, TT4), free and total triiodothyronine (FT3, TT3), and thyroglobulin (TGN) was evaluated. Data from National Health and Nutrition Examination Survey for the years 2007–2008 were used for this evaluation. TSH levels increased with increase in levels of PFOA (p<0.01). There were no statistically significant associations between the levels of FT3, and FT4 with the levels of any of the six PFAAs. Levels of TT3 were found to increase with the levels of PFOA (p=0.01) and TT4 levels were found to increase with increase in PFHxS levels (p<0.01). Males had statistically significantly higher levels of FT3 than females and females had statistically significantly higher levels of TT4 than males. As compared to non-Hispanics whites and Hispanics, non-Hispanic blacks had lower levels of TSH, FT3, TT3, and TT4 but Hispanics had the lowest levels of TGN. Age was negatively associated with FT3 and TT3 but positively associated with FT4 and TT4. Non-smokers had higher levels of TSH and TT4 than smokers and smokers had higher levels of FT3 and TGN than non-smokers. Iodine deficiency was associated with increased levels of TSH, TT3, TT4, and TGN. -- Highlights: • Levels of total triiodothyronine were found to increase with the levels of PFOA. • Total thyroxine increased with increase in levels of perfluorohexane sulfonic acid. • There was a positive association between the levels of PFOA and TSH. • Iodine deficiency was associated with elevated levels of TSH, total T3 and T4. • Iodine deficiency was associated with elevated levels of thyroglobulin.

Jain, Ram B., E-mail: Jain.ram.b@gmail.com

2013-10-15

140

Mutual impacts of wheat (Triticum aestivum L.) and earthworms (Eisenia fetida) on the bioavailability of perfluoroalkyl substances (PFASs) in soil.  

PubMed

Wheat and earthworms were exposed individually and together to soils contaminated with 11 perfluoroalkyl substances (PFASs). Wheat accumulated PFASs from soil with root concentration factors and bioconcentration factors that decreased as the number of perfluorinated carbons in the molecule increased. Earthworms accumulated PFASs from soil with biota-to-soil accumulation factors that increased with the number of carbons. Translocation factors (TF) of perfluorinated carboxylates (PFCAs) in wheat peaked at perfluorohexanoic acid and decreased significantly as the number of carbons increased or decreased. Perfluorohexane sulfonate produced the greatest TF of the three perfluorinated sulfonates (PFSAs) examined. Wheat increased the bioaccumulation of all 11 PFASs in earthworms and earthworms increased the bioaccumulation in wheat of PFCAs containing seven or less perfluorinated carbons, decreased bioaccumulation of PFCAs with more than seven carbons, and decreased bioaccumulation of PFSAs. In general, the co-presence of wheat and earthworms enhanced the bioavailability of PFASs in soil. PMID:24158108

Zhao, Shuyan; Fang, Shuhong; Zhu, Lingyan; Liu, Li; Liu, Zhengtao; Zhang, Yahui

2014-01-01

141

Spatial distribution and partitioning behavior of selected poly- and perfluoroalkyl substances in freshwater ecosystems: A French nationwide survey.  

PubMed

The spatial distribution and partitioning of 22 poly- and perfluoroalkyl substances (PFASs) in 133 selected rivers and lakes were investigated at a nationwide scale in mainland France. ?PFASs was in the rangeperfluoroalkyl carboxylates (PFCAs) often dominating the PFAS profile (e.g., PFCAs>99% of ?PFASs in the sediment, likely as a consequence of industrial point source discharge). Several treatments for data below detection limits (non-detects) were used to compute descriptive statistics, differences among groups, and correlations between congeners, as well as log Kd and log Koc partition coefficients; in that respect, the Regression on Order Statistics (robust ROS) method was preferred for descriptive statistics computation while the Akritas-Theil-Sen estimator was used for regression and correlation analyses. Multiple regression results suggest that PFAS levels in the dissolved phase and sediment characteristics (organic carbon fraction and grain size) may be significant controlling factors of PFAS levels in the sediment. PMID:25721143

Munoz, Gabriel; Giraudel, Jean-Luc; Botta, Fabrizio; Lestremau, François; Dévier, Marie-Hélčne; Budzinski, Hélčne; Labadie, Pierre

2015-06-01

142

Poly(perfluoroalkylation) of metallic nitride fullerenes reveals addition-pattern guidelines: synthesis and characterization of a family of Sc3N@C80(CF3)n (n = 2-16) and their radical anions.  

PubMed

A family of highly stable (poly)perfluoroalkylated metallic nitride cluster fullerenes was prepared in high-temperature reactions and characterized by spectroscopic (MS, (19)F NMR, UV-vis/NIR, ESR), structural and electrochemical methods. For two new compounds, Sc(3)N@C(80)(CF(3))(10) and Sc(3)N@C(80)(CF(3))(12,) single crystal X-ray structures are determined. Addition pattern guidelines for endohedral fullerene derivatives with bulky functional groups are formulated as a result of experimental ((19)F NMR spectroscopy and single crystal X-ray diffraction) studies and exhaustive quantum chemical calculations of the structures of Sc(3)N@C(80)(CF(3))(n) (n = 2-16). Electrochemical studies revealed that Sc(3)N@C(80)(CF(3))(n) derivatives are easier to reduce than Sc(3)N@C(80), the shift of E(1/2) potentials ranging from +0.11 V (n = 2) to +0.42 V (n = 10). Stable radical anions of Sc(3)N@C(80)(CF(3))(n) were generated in solution and characterized by ESR spectroscopy, revealing their (45)Sc hyperfine structure. Facile further functionalizations via cycloadditions or radical additions were achieved for trifluoromethylated Sc(3)N@C(80) making them attractive versatile platforms for the design of molecular and supramolecular materials of fundamental and practical importance. PMID:21294511

Shustova, Natalia B; Peryshkov, Dmitry V; Kuvychko, Igor V; Chen, Yu-Sheng; Mackey, Mary A; Coumbe, Curtis E; Heaps, David T; Confait, Bridget S; Heine, Thomas; Phillips, J Paige; Stevenson, Steven; Dunsch, Lothar; Popov, Alexey A; Strauss, Steven H; Boltalina, Olga V

2011-03-01

143

Chemical etching of bovine serum albumin-protected Au25 nanoclusters for label-free and separation-free detection of cysteamine.  

PubMed

This study describes a novel Au nanocluster-based fluorescent sensor for label-free, separation-free and selective detection of cysteamine (CSH). The sensing mechanism is based on CSH etching-induced fluorescence quenching of the bovine serum albumin-protected Au25 nanoclusters (BSAGNCs). A series of characterizations is carried out towards a better understanding of the CSH-induced fluorescence quenching of the BSAGNCs. It is found that CSH can etch the Au25 nanoclusters, exhibiting the potent etching activity. Other thiol-containing compounds such as glutathione and cysteine and other 19 natural amino acids do not interfere with such CSH-induced etching process. The decreases in fluorescence intensity of the BSAGNCs allow sensitive detection of free CSH in the range of 500-10,000nM. The detection limit for CSH is 150nM (S/N=3). The spiked human serum samples can be analyzed with satisfactory results. PMID:25460897

Shu, Tong; Su, Lei; Wang, Jianxing; Li, Chenzhong; Zhang, Xueji

2015-04-15

144

Occurrence and transport of 17 perfluoroalkyl acids in 12 coastal rivers in south Bohai coastal region of China with concentrated fluoropolymer facilities.  

PubMed

Perfluoroalkyl acids (PFAAs) are emerging contaminants that have raised great concern in recent years. While PFAAs manufacturing becomes regulated in developed countries, production has been partly shifted to China. Eight fluoropolymer manufacturing facilities located in the South Bohai coastal region, one of the most populated areas of China, have been used to manufacture PFAA-related substances since 2001. The environmental consequence of the intensive production of PFAAs in this region remains largely unknown. We analyzed 17 PFAAs in twelve coastal rivers of this region, and found staggeringly high concentrations of perfluorooctanoic acid (PFOA) ranging from 0.96 to 4534.41 ng/L. The highest concentration was observed in the Xiaoqing River which received effluents from certain fluoropolymer facilities. Principal component analysis indicated similar sources of several perfluoroalkyl carboxylic acids (PFCAs) in all rivers, which indicated that atmospheric transport, wastewater treatment and surface runoff also acted as important supplements to direct discharge to surface water. PMID:24747105

Wang, Pei; Lu, Yonglong; Wang, Tieyu; Fu, Yaning; Zhu, Zhaoyun; Liu, Shijie; Xie, Shuangwei; Xiao, Yang; Giesy, John P

2014-07-01

145

Congener-specific organic carbon-normalized soil and sediment-water partitioning coefficients for the C1 through C8 perfluoroalkyl carboxylic and sulfonic acids  

Microsoft Academic Search

Organic carbon-normalized soil and sediment-water partitioning coefficients (Koc) were estimated for all C1 through C8 perfluoroalkyl carboxylic (PFCA) and sulfonic (PFSA) acid congeners. The limited experimental Koc data set for the straight chain C7 through C10 PFCAs and C8 and C10 PFSAs was correlated to SPARC and ALOGPS computationally estimated octanol-water partitioning\\/distribution constants and used to predict Koc values for

Sierra Rayne; Kaya Forest

2009-01-01

146

Effect of Equivalent Weight on Water Sorption, PTFE-Like Crystallinity, and Ionic Conductivity in Bis((Perfluoroalkyl)Sulfonyl) Imide Perfluorinated Ionomers  

Microsoft Academic Search

Measurements of water absorption and ionic conductivity as a function of relative humidity (RH) were carried out on membranes comprised of bis((perfluoroalkyl)sulfonyl) imide ionomers of equivalent weights 1470, 1200, and 1075 g equiv-1, and on a sample of the perfluorosulfonic ionomer Nafion™ ionomer of equivalent weight 1100 g equiv-1 for comparison. All of the ionomers exhibited decreased water absorption and

J. R. Atkins; C. R. Sides; S. E. Creager; J. L. Harris; W. T. Pennington; B. H. Thomas; D. D. DesMarteau

147

A Comparison of RIA and LC-MS/MS Methods to Quantify Steroids in Rat Serum and Urine Following Exposure to an Endocrine Disrupting Chemical  

EPA Science Inventory

Commercially available radio immunoassays (RIM) are frequently used in toxicological studies to evaluate effects of endocrine disrupting chemicals (EDCs) on steroidogenesis in rats. Currently there are limited data comparing steroid concentrations in rats as measured by RIM to th...

148

Mechanisms of perfluoroalkyl acid (PFAA) toxicity: Involvement of peroxisome proliferator activator receptor alpha (PPAR) molecular signals.  

EPA Science Inventory

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are members of a family of environmentally persistent perfluorinated compounds and are found in the serum of wildlife and humans. PFOS and PFOA are developmentally toxic in rats and mice. Exposure in utero reduces...

149

Serum and tumour ferritins in primary liver cancer  

Microsoft Academic Search

Serum ferritin concentrations were found to be raised, often considerably, in 58 of 76 black patients with primary liver cancer (PLC). No correlation could be demonstrated between the serum ferritin concentration and several other measurements, including the following: hepatic iron stores measured chemically, the size of the tumour, serum transaminase values, and the presence or absence of cirrhosis in the

M C Kew; J D Torrance; D Derman; M Simon; G M Macnab; R W Charlton; T H Bothwell

1978-01-01

150

Probing the binding of an endocrine disrupting compound-Bisphenol F to human serum albumin: insights into the interactions of harmful chemicals with functional biomacromolecules.  

PubMed

Bisphenol F (BPF) as an endocrine disrupting compounds (EDCs) pollutant in the environment poses a great threat to human health. To evaluate the toxicity of BPF at the protein level, the effects of BPF on human serum albumin (HSA) were investigated at three temperatures 283, 298, and 308 K by multiple spectroscopic techniques. The experimental results showed that BPF effectively quenched the intrinsic fluorescence of HSA via static quenching. The number of binding sites, the binding constant, the thermodynamic parameters and the binding subdomain were measured, and indicated that BPF could spontaneously bind with HSA on subdomain IIA through H-bond and van der Waals interactions. Furthermore, the conformation of HSA was demonstrably changed in the presence of BPF. The work provides accurate and full basic data for clarifying the binding mechanisms of BPF with HSA in vivo and is helpful for understanding its effect on protein function during its transportation and distribution in blood. PMID:24973668

Pan, Fang; Xu, Tianci; Yang, Lijun; Jiang, Xiaoqing; Zhang, Lei

2014-11-11

151

Probing the binding of an endocrine disrupting compound-Bisphenol F to human serum albumin: Insights into the interactions of harmful chemicals with functional biomacromolecules  

NASA Astrophysics Data System (ADS)

Bisphenol F (BPF) as an endocrine disrupting compounds (EDCs) pollutant in the environment poses a great threat to human health. To evaluate the toxicity of BPF at the protein level, the effects of BPF on human serum albumin (HSA) were investigated at three temperatures 283, 298, and 308 K by multiple spectroscopic techniques. The experimental results showed that BPF effectively quenched the intrinsic fluorescence of HSA via static quenching. The number of binding sites, the binding constant, the thermodynamic parameters and the binding subdomain were measured, and indicated that BPF could spontaneously bind with HSA on subdomain IIA through H-bond and van der Waals interactions. Furthermore, the conformation of HSA was demonstrably changed in the presence of BPF. The work provides accurate and full basic data for clarifying the binding mechanisms of BPF with HSA in vivo and is helpful for understanding its effect on protein function during its transportation and distribution in blood.

Pan, Fang; Xu, Tianci; Yang, Lijun; Jiang, Xiaoqing; Zhang, Lei

2014-11-01

152

Hazard quotient profiles used as a risk assessment tool for PFOS and PFOA serum levels in three distinctive European populations.  

PubMed

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) blood levels are commonly used as biomarkers of human environmental exposure to these compounds. Many biomonitoring studies indicate 100% detection for PFOS and PFOA thus justifying a concern of possible risk for the most exposed individuals. This study addresses the predictive value of hazard quotients (HQs) calculated on the basis of serum PFOS and PFOA in male and female populations of reproductive age in Greenland, Poland and Ukraine. Overall, 2026 results of PFOS and PFOA serum concentrations (589 males, 1437 females) were obtained from the INUENDO database. HQs were calculated from the actual biomonitoring results and literature-based animal data linking toxicological outcomes and critical PFOS/PFOA serum levels. HQs for serum PFOS were calculated based on Points of Departure (PoD) at 13?gmL(-1) (cynomolgus monkeys, 183days, changes in THS and T3) and for PFOA at 7.1?gmL(-1) serum (male rats, 90days, hepatocellular necrosis, increased liver weight). Uncertainty factors were applied to reflect interspecies differences and human variability. Serum HQs were expressed as a ratio relative to the point of departure for each PFOS and PFOA. Only in the three cases of males in Greenland were there serum PFOS levels showing HQ values exceeding 1, so indicating that such serum levels may be of concern. The mean serum concentration of PFOS was significantly higher in male than in female populations. Despite significant differences between HQ profiles for PFOS and PFOA in donors from Greenland, Poland and Ukraine, the concentrations of these perfluoroalkylated compounds do not indicate a cause for concern, except for the three aforementioned cases from Greenland. This study demonstrates that the HQ approach can help to interpret human biomonitoring data and thus serve as a valuable tool in further risk assessment priority settings and may also be used as a basis for taking decisions in risk management. PMID:25454227

Ludwicki, Jan K; Góralczyk, Katarzyna; Struci?ski, Pawe?; Wojtyniak, Bogdan; Rabczenko, Daniel; Toft, Gunnar; Lindh, Christian H; Jönsson, Bo A G; Lenters, Virissa; Heederik, Dick; Czaja, Katarzyna; Hernik, Agnieszka; Pedersen, Henning S; Zvyezday, Valentyna; Bonde, Jens Peter

2015-01-01

153

Chemical composition of natural and polyphenol-free apple pomace and the effect of this dietary ingredient on intestinal fermentation and serum lipid parameters in rats.  

PubMed

Unprocessed pomace containing 61% of dietary fiber (DF) and 0.23% of polyphenols (PP) and ethanol- or ethanol/acetone-extracted pomaces containing 66% DF and 0.10% PP and 67% DF and 0.01% PP, respectively, were subjected to a 4 week study in rats. The aim of the study was assessing the advantages of dietary supplementation with the above pomaces. To measure the animal response to dietary treatments, parameters describing cecal fermentation and lipoprotein profile were assessed. The dietary use of 5% unprocessed pomace caused an increase in cecal short-chain fatty acid (SCFA) production and a decrease in blood triacylglycerols, leading to a drop in serum atherogenic index. Ethanol-extracted pomace increased the glycolytic activity of cecal microbiota and decreased cecal branched-chain fatty acid production, whereas acetone extraction led to lower cecal ammonia concentration, decreased colonic pH value, and higher HDL/total cholesterol ratio. The variations in the atherogenic index indicate flavonoids as the key pomace component in relation to blood lipid profile benefits. PMID:21805963

Kosmala, Monika; Ko?odziejczyk, Krzysztof; Zdu?czyk, Zenon; Ju?kiewicz, Jerzy; Boros, Danuta

2011-09-14

154

National inventory of perfluoroalkyl substances in archived U.S. biosolids from the 2001 EPA National Sewage Sludge Survey  

PubMed Central

Using liquid chromatography tandem mass spectrometry, we determined the first nationwide inventories of 13 perfluoroalkyl substances (PFASs) in U.S. biosolids via analysis of samples collected by the U.S. Environmental Protection Agency in the 2001 National Sewage Sludge Survey. Perfluorooctane sulfonate [PFOS; 403 ± 127 ng/g dry weight (dw)] was the most abundant PFAS detected in biosolids composites representing 32 U.S. states and the District of Columbia, followed by perfluorooctanoate [PFOA; 34 ± 22 ng/g dw] and perfluorodecanoate [PFDA; 26 ± 20 ng/g dw]. Mean concentrations in U.S. biosolids of the remaining ten PFASs ranged between 2 and 21 ng/g dw. Interestingly, concentrations of PFOS determined here in biosolids collected prior to the phase-out period (2002) were similar to levels reported in the literature for recent years. The mean load of ?PFASs in U.S. biosolids was estimated at 2749–3450 kg/year, of which about 1375–2070 kg is applied on agricultural land and 467–587 kg goes to landfills as an alternative disposal route. This study informs the risk assessment of PFASs by furnishing national inventories of PFASs occurrence and environmental release via biosolids application on land. PMID:23562984

Venkatesan, Arjun K.; Halden, Rolf U.

2013-01-01

155

Using blood gene signatures for assessing effects of exposure to perfluoroalkyl acids (PFAAs) in humans: the NOWAC postgenome study  

PubMed Central

Perfluoroalkyl acids (PFAAs) are ubiquitously present in human blood samples and the effects of these compounds on human health are not fully characterized. This study was conducted in order to investigate the applicability of peripheral blood gene expressions for exploring the impact of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA) and perfluorohexane sulfonate (PFHxS) exposure on the general population. PFOS, PFOA and PFHxS were analyzed in blood samples from a representative group of 270 healthy, postmenopausal Norwegian women (48-62 years). Gene expression was measured in the same samples using the Applied Biosystems microarray platform. Forty-eight different gene sets, all previously linked to PFAA exposure were explored in relation to the selected PFAAs. Two gene sets, both related to the citric acid cycle, were differentially expressed between the “PFOS high” (>30ng/ml, n=42) and the “PFOS low” (<30ng/ml, n=228) group. Based on the results of this study we believe that blood gene signatures have a large potential for elucidating which biological pathways are being affected by environmental pollutants. To the best of our knowledge, this study is the first assessment of the impact of PFAAs on blood gene expressions in humans from the general population. PMID:21915359

Rylander, Charlotta; Dumeaux, Vanessa; Olsen, Karina Standahl; Waaseth, Marit; Sandanger, Torkjel M; Lund, Eiliv

2011-01-01

156

Seasonal variations and spatial distributions of perfluoroalkyl substances in the rivers Elbe and lower Weser and the North Sea.  

PubMed

The spatial distributions and seasonal variations of perfluoroalkyl substances (PFASs) in surface waters were investigated for the German rivers Elbe and lower Weser, and the North Sea. ?PFAS concentrations ranged from 4.1 to 250ngL(-1) in the River Elbe, from 3.8 to 16ngL(-1) in the lower Weser, and from 0.13 to 10ngL(-1) in the North Sea. The most abundant compound was perfluorobutanesulfonate (PFBS) with a proportion of 24% in river water and 31% in seawater samples. The concentrations of perfluorohexanoic acid (PFHxA) and perfluorooctanoic acid (PFOA) in Elbe River water showed significant seasonal variation in 2011. The seasonal variations might be related to the variations of water discharge. The highest concentrations of PFOA and PFHxA were detected in August. Pearson correlations showed that perfluorobutanoic acid (PFBA) and PFBS had different sources from other PFASs, and the current manufacturing and use of C4-based products could explain the distinction. The estimated fluxes of individual substances and ?PFASs in the River Elbe showed no significant seasonal variation. The annual fluxes of PFASs to the North Sea were estimated to be 335±100kgyear(-1) from the River Elbe and 102±22kgyear(-1) from the River Weser. PMID:24768527

Zhao, Zhen; Xie, Zhiyong; Tang, Jianhui; Sturm, Renate; Chen, Yingjun; Zhang, Gan; Ebinghaus, Ralf

2015-06-01

157

Effective removal of albumin from serum.  

PubMed

The protein constituents of serum can range from grams to picograms per liter, making it technically difficult to achieve in-depth proteomic analysis. Removal of highly abundant proteins, such as albumin, coupled to powerful protein separation methods is required for increased sample load, thus facilitating detection and identification of low-abundant proteins. We report here a chemical-based extraction method for the effective and specific removal of albumin from serum. PMID:16145708

Colantonio, David A; Dunkinson, Christy; Bovenkamp, Diane E; Van Eyk, Jennifer E

2005-10-01

158

Effects of Perfluorinated Phosphonic Acid Exposure during pregnancy in the mouse  

EPA Science Inventory

Perfluorinated phosphonic acids (PFPAs) are a member of the perfluoroalkyl acid (PFAA) family, and are structurally similar to the perfluoroalkyl sulfonates and perfluoroalkyl carboxylates. These chemicals have recently been detected in the environment, particularly in surface wa...

159

Protein electrophoresis - serum  

MedlinePLUS

This lab test measures the types of protein in the fluid (serum) part of a blood sample. Other electrophoresis tests that measure proteins in the serum include: Immunoelectrophoresis Immunofixation Globulin electrophoresis

160

Perfluoroalkyl carboxylic acids with up to 22 carbon atoms in snow and soil samples from a ski area.  

PubMed

The use of fluorinated ski waxes as a direct input route of perfluoroalkyl carboxylic acids (PFCAs) to the environment was investigated. PFCA homologues with 6-22 carbon atoms (C6-22 PFCAs) were detected in fluorinated ski waxes and their raw materials by liquid chromatography coupled to tandem mass spectrometry. Snow and soil samples from a ski area in Sweden were taken after a skiing competition and after snowmelt, respectively. In both snow and soil samples C6-22 PFCAs were detected, representing the first report of PFCAs with up to 22 carbon atoms in environmental samples. Single analyte concentrations in snow (analyzed as melt water) and soil ranged up to 0.8?gL(-1) and 5ngg(-1) dry weight, respectively. ?PFCA concentrations in snow and soil decreased from the start to the finish of the ski trail. Distinct differences in PFCA patterns between snow (prevalence of C14-20 PFCAs) and soil samples (C6-14 PFCAs dominating) were observed. Additionally, a PFCA pattern change from the start to about two third of the distance of the ski trail was found both for snow and soil, with a larger fraction of longer chain homologues present in samples from the start. These observations are probably a result of differences in PFCA homologue patterns present in different types of waxes. The calculated PFCA input from snow affected by the skiing competition was smaller than the PFCA inventory in soil for all chain lengths and markedly smaller for C6-15 PFCAs, presenting evidence for long-term accumulation in soil. PMID:23466094

Plassmann, Merle M; Berger, Urs

2013-05-01

161

Occurrence of perfluoroalkyl substances (PFASs) in various food items of animal origin collected in four European countries.  

PubMed

This study summarises the results of the levels of 21 perfluoroalkyl substances (PFASs) in 50 selected pooled samples representing 15 food commodities with the special focus on those of animal origin, as meat, seafood, fish, milk, dairy products and hen eggs, which are commonly consumed in various European markets, e.g. Czech, Italian, Belgian and Norwegian. A new, rapid sample preparation approach based on the QuEChERS extraction procedure was applied. Ultra-performance liquid chromatography (UHPLC) coupled to tandem mass spectrometry (MS/MS) employing electrospray ionisation (ESI) in negative mode was used for the quantification of target analytes. Method quantification limits (MQLs) were in the range of 1-10 ng kg(-1) (ng l(-1)) for fish, meat, hen eggs, cheese and milk, and in the range of 2.5-125 ng kg(-1) for butter. Only 16 of the group of 21 PFASs were found in at least one analysed sample. From 16 PFASs, perfluorooctane sulfonate (PFOS) was the most frequently detected analyte present in approximately 50% of samples (in the range of 0.98-2600 ng kg(-1)). PFCAs with C8-C14 carbon chain were presented in approximately 20% of samples. The concentration ranges of individual compounds in the respective groups of PFASs were: 2.33-76.3 ng kg(-1) for PFSAs (without PFOS), 4.99-961 ng kg(-1) for PFCAs, 10.6-95.4 ng kg(-1) for PFPAs, and 1.61-519 ng kg(-1) for FOSA. The contamination level in the analysed food commodities decreased in the following order: seafood > pig/bovine liver > freshwater/marine fish > hen egg > meat > butter. When comparing the total contamination and profiles of PFASs in food commodities that originated from various sampling countries, differences were identified, and the contents decreased as follows: Belgium > Norway, Italy > Czech Republic. PMID:24107131

Hlouskova, Veronika; Hradkova, Petra; Poustka, Jan; Brambilla, Gianfranco; De Filipps, Stefania Paola; D'Hollander, Wendy; Bervoets, Lieven; Herzke, Dorte; Huber, Sandra; de Voogt, Pim; Pulkrabova, Jana

2013-01-01

162

High levels of perfluoroalkyl acids in eggs and embryo livers of great cormorant (Phalacrocorax carbo sinensis) and herring gull (Larus argentatus) from Lake Vänern, Sweden.  

PubMed

In the eggs and developing chick livers in the two wild bird species, great cormorant and herring gull, the concentrations of a range of 15 perfluoroalkyl acids (PFAAs) were determined. Eggs of the two species were collected from Lake Vänern, Sweden, and analysed either as undeveloped egg (whole egg or separated into yolk and albumen) or incubated until start of the hatching process when the chick liver was removed and analysed. High levels of PFAAs were found in all matrixes except albumen. The predominant PFAA was perfluorooctane sulfonate (PFOS), which was found in the ?g/g wet weight (ww) range in some samples of cormorant whole egg, yolk and liver and herring gull egg yolk and liver. The average concentration in yolk was 1,506 ng/g ww in cormorant and 589 ng/g ww in herring gull. The average liver concentrations of PFOS were 583 ng/g ww in cormorant and 508 ng/g ww in herring gull. At these concentrations, biochemical effects in the developing embryo or effects on embryo survival cannot be ruled out. For perfluoroalkyl carboxylates (PFCAs), the liver/egg and liver/yolk concentration ratios increased with PFCA chain length in cormorant but not in herring gull, indicating that chain length could possibly affect egg-to-liver transfer of PFCAs and that species differences may exist. PMID:23463275

Nordén, Marcus; Berger, Urs; Engwall, Magnus

2013-11-01

163

Serum factors and clinical characteristics associated with serum E-Screen activity  

PubMed Central

Background The E-Screen bioassay can measure the mitogenicity of human serum and thus may be useful as a biomarker in epidemiologic studies of breast cancer. While the assay’s MCF-7 cells are known to proliferate in response to estrogen, the specific determinants of variation in E-Screen activity in human serum samples are poorly understood. We sought to identify serum molecules and patient characteristics associated with serum E-Screen activity among postmenopausal women. Methods Postmenopausal women (N=219) aged 55–70 with no history of postmenopausal hormone use or breast cancer completed a questionnaire and provided a blood sample. Serum was analyzed for E-Screen activity and a variety of molecules including sex hormones, growth factors, and environmental chemicals. Stepwise selection procedures were used to identify correlates of E-Screen activity. Results Serum samples from all women had detectable E-Screen activity, with a median estradiol equivalents value of 0.027 ng/mL and interquartile range of 0.018–0.036 ng/mL. In the final multivariable-adjusted model, serum E-Screen activity was positively associated with serum estradiol, estrone, IGFBP-3, and testosterone levels (p<0.05), as well as body mass index (p=0.03). Serum E-Screen activity was lower among women with higher SHBG (p<0.0001) and progesterone levels (p=0.03). Conclusion Serum E-Screen activity varies according to levels of endogenous estrogens and other serum molecules. Obesity appears to confer additional serum mitogenicity beyond its impact on the measured hormones and growth factors. Impact By capturing mitogenicity due to a variety of patient and serum factors, the E-Screen may provide advantages for use as a biomarker in breast cancer studies. PMID:23588007

Wang, Jue; Trentham-Dietz, Amy; Hemming, Jocelyn D. C.; Hedman, Curtis J.; Sprague, Brian L.

2013-01-01

164

Quantitation of gas-phase perfluoroalkyl surfactants and fluorotelomer alcohols released from nonstick cookware and microwave popcorn bags.  

PubMed

Fluoropolymer dispersions are used for coating certain cookware products and food-contact packaging to impart oil and water repellency. Since salts of perfluorooctanoic acid (PFOA) are used as a processing aid in the manufacture of many fluoropolymers, it is necessary to determine if these compounds are still present as residuals after the process used to coat nonstick cookware or packaging, and could be released during typical cooking conditions. In this study, we identified and measured perfluoroalkyl carboxylates (PFCAs), particularly PFOA, and fluorotelomer alcohols (FTOHs; 6:2 FTOH and 8:2 FTOH), released from nonstick cookware into the gas phase under normal cooking temperatures (179 to 233 degrees C surface temperature). PFOA was released into the gas phase at 7-337 ng (11-503 pg/cm2) per pan from four brands of nonstick frying pans. 6:2 FTOH and 8:2 FTOH were found in the gas phase of four brands of frying pans, and the sources of FTOHs released from nonstick cookware are under investigation. We observed a significant decrease in gas-phase PFOA following repeated use of one brand of pan, whereas the other brand did not show a significant reduction in PFOA release following multiple uses. PFOA was found at >5 ng during the fourth use of both brands of pans. FTOHs were not found after the second use of either brand of pans. PFOA was found at 5-34 ng in the vapors produced from a prepacked microwave popcorn bag. PFOA was not found in the vapors produced from plain white corn kernels popped in a polypropylene container. 6:2 FTOH and 8:2 FTOH were measured in the vapors produced from one brand of prepacked microwave popcorn at 223 + 37 ng and 258 +/- 36 ng per bag, respectively, but not measured at >20 ng (LOQ) in the other two brands. On the packaging surface of one brand of microwave popcorn several PFCAs, including C5-C12, 6:2 FTOH, and 8:2 FTOH, were found at concentrations in the order of 0.5-6.0 ng/cm2. This study suggests that residual PFOA is not completely removed during the fabrication process of the nonstick coating for cookware. They remain as residuals on the surface and may be off-gassed when heated at normal cooking temperatures. PMID:17593716

Sinclair, Ewan; Kim, Seung Kyu; Akinleye, Henry B; Kannan, Kurunthachalam

2007-02-15

165

Assessing the relationship between perfluoroalkyl substances, thyroid hormones and binding proteins in pregnant women; a longitudinal mixed effects approach.  

PubMed

The mechanisms involved in thyroid homeostasis are complex, and perfluoroalkyl substances (PFASs) have been indicated to interfere at several levels in this endocrine system. Disruption of the maternal thyroid homeostasis during early pregnancy is of particular concern, where subclinical changes in maternal thyroid hormones (THs) may affect embryonic and foetal development. The present study investigated associations between THs, thyroid binding proteins (TH-BPs) and PFAS concentrations in pregnant women from Northern Norway. Women participating in The Northern Norway Mother-and-Child contaminant Cohort Study (MISA) donated a blood sample at three visits related to their pregnancy and postpartum period (during the second trimester, 3days and 6weeks after delivery) in the period 2007-2009. Participants were assigned to quartiles according to PFAS concentrations during the second trimester and mixed effects linear models were used to investigate potential associations between PFASs and repeated measurements of THs, TH-BPs, thyroxin binding capacity and thyroid peroxidase antibodies (anti-TPOs). Women within the highest perfluorooctane sulfonate (PFOS) quartile had 24% higher mean concentrations of thyroid stimulating hormone (TSH) compared to the first quartile at all sampling points. Women within the highest quartiles of perfluorodecanoate (PFDA) had 4% lower mean concentrations of triiodothyronine (T3) and women within the highest quartile of perfluoroundecanoate (PFUnDA) had 3% lower mean concentrations of free triiodothyronine (FT3). Further, the difference in concentrations and the changes between three time points were the same for the PFAS quartiles. Thyroxin binding capacity was associated with all the THs and TH-BPs, and was selected as a holistic adjustment for individual changes in TH homeostasis during pregnancy. Finally, adjusting for maternal iodine status did not influence the model predictions. Findings in the present study suggest modifications of TH homeostasis by PFASs in a background exposed maternal population. The variation in levels of THs between PFAS quartiles was within normal reference ranges and may not be of clinical significance in the pregnant woman. However, subtle individual changes in maternal THs may have significant consequences for foetal health. PMID:25647630

Berg, Vivian; Nřst, Therese Haugdahl; Hansen, Solrunn; Elverland, Astrid; Veyhe, Anna-Sofía; Jorde, Rolf; Odland, Jon Řyvind; Sandanger, Torkjel Manning

2015-04-01

166

Serum transferrin receptor.  

PubMed

The transferrin receptor plays a critical role in iron metabolism by precisely controlling the flow of transferrin iron into body cells. A soluble truncated form of the receptor can be detected in human serum using sensitive immunoassays, and the initial clinical experience with this new measurement indicates that it reflects the total body mass of tissue receptor. Serum receptor levels rise significantly with tissue iron deficiency and the heightened demand for iron associated with expansion of the erythroid marrow. The serum receptor provides a quantitative measure of functional iron deficiency and distinguishes the associated anemia from that of chronic disease. If iron deficiency is excluded, the serum receptor provides a quantitative measure of total erythropoiesis that is more sensitive and less invasive than bone marrow examination currently used to assess red cell precursor mass. Performed in conjunction with serum ferritin measurements, the serum receptor will be useful in establishing the true prevalence of iron deficiency anemia in population studies. PMID:8476268

Cook, J D; Skikne, B S; Baynes, R D

1993-01-01

167

Characterization and distribution of heavy metals, polybrominated diphenyl ethers and perfluoroalkyl substances in surface sediment from the dayan river, South china.  

PubMed

In this study, surface sediment samples were collected from 11 sites in the Dayan River near an electronic waste site in Qingyuan. Heavy metals, polychlorinated biphenyls (PBDEs) and perfluoroalkyl substances (PFASs) were detected. The concentrations of Cu, Zn, Pb and Cd ranged from 12.1 to 641, 47.1 to 891, 39.2 to 641, 0.12 to 2.07 mg/kg dw, respectively. Total PBDEs ranged between 0.052 and 126.64 ng/g dw. BDE-47 and BDE-99 were the predominant PBDEs. The concentrations of PFASs in sediments ranged between 0.01 and 3.72 ng/g dw. The perfluorooctane sulfonate was predominantly PFASs. The strong positive correlations among Cu, Zn, perfluorooctanoic acid and PBDEs indicate that these contaminants were associated with each other and may share a common anthropogenic source in the sediments of the Dayan River. PMID:25666566

Zheng, Hai; Hu, Guocheng; Xu, Zhencheng; Li, Huashou; Zhang, Lijuan; Zheng, Jing; Chen, Laiguo; He, Dechun

2015-04-01

168

Gestational Exposure to Endocrine-Disrupting Chemicals and Reciprocal Social, Repetitive, and Stereotypic Behaviors in 4- and 5-Year-Old Children: The HOME Study  

PubMed Central

Background: Endocrine-disrupting chemicals (EDCs) may be involved in the etiology of autism spectrum disorders, but identifying relevant chemicals within mixtures of EDCs is difficult. Objective: Our goal was to identify gestational EDC exposures associated with autistic behaviors. Methods: We measured the concentrations of 8 phthalate metabolites, bisphenol A, 25 polychlorinated biphenyls (PCBs), 6 organochlorine pesticides, 8 brominated flame retardants, and 4 perfluoroalkyl substances in blood or urine samples from 175 pregnant women in the HOME (Health Outcomes and Measures of the Environment) Study (Cincinnati, OH). When children were 4 and 5 years old, mothers completed the Social Responsiveness Scale (SRS), a measure of autistic behaviors. We examined confounder-adjusted associations between 52 EDCs and SRS scores using a two-stage hierarchical analysis to account for repeated measures and confounding by correlated EDCs. Results: Most of the EDCs were associated with negligible absolute differences in SRS scores (? 1.5). Each 2-SD increase in serum concentrations of polybrominated diphenyl ether-28 (PBDE-28) (? = 2.5; 95% CI: –0.6, 5.6) or trans-nonachlor (? = 4.1; 95% CI: 0.8–7.3) was associated with more autistic behaviors. In contrast, fewer autistic behaviors were observed among children born to women with detectable versus nondetectable concentrations of PCB-178 (? = –3.0; 95% CI: –6.3, 0.2), ?-hexachlorocyclohexane (? = –3.3; 95% CI: –6.1, –0.5), or PBDE-85 (? = –3.2; 95% CI: –5.9, –0.5). Increasing perfluorooctanoate (PFOA) concentrations were also associated with fewer autistic behaviors (? = –2.0; 95% CI: –4.4, 0.4). Conclusions: Some EDCs were associated with autistic behaviors in this cohort, but our modest sample size precludes us from dismissing chemicals with null associations. PFOA, ?-hexachlorocyclohexane, PCB-178, PBDE-28, PBDE-85, and trans-nonachlor deserve additional scrutiny as factors that may be associated with childhood autistic behaviors. Citation: Braun JM, Kalkbrenner AE, Just AC, Yolton K, Calafat AM, Sjödin A, Hauser R, Webster GM, Chen A, Lanphear BP. 2014. Gestational exposure to endocrine-disrupting chemicals and reciprocal social, repetitive, and stereotypic behaviors in 4- and 5-year-old children: the HOME Study. Environ Health Perspect 122:513–520;?http://dx.doi.org/10.1289/ehp.1307261 PMID:24622245

Kalkbrenner, Amy E.; Just, Allan C.; Yolton, Kimberly; Calafat, Antonia M.; Sjödin, Andreas; Hauser, Russ; Webster, Glenys M.; Chen, Aimin; Lanphear, Bruce P.

2014-01-01

169

Partial replacement of serum by selenite, transferrin, albumin and lecithin in haemopoitec cell cultures  

Microsoft Academic Search

CULTURE media for mammalian cells usually require supplementation with serum to supply as yet undefined needs. Because the requirements are likely to be multiple, it is difficult to distinguish biologically between the effects of nonspecific `nutritional' factors in serum and those of specific regulatory factors. Partial replacement of serum in these systems by chemically defined substances supplying the nonspecific needs

L. J. Guilbert; N. N. Iscove

1976-01-01

170

Serum free hemoglobin test  

MedlinePLUS

Blood hemoglobin; Serum hemoglobin ... Hemoglobin (Hb) is the main component of red blood cells. It is a protein that carries oxygen. ... Disorder in which there is excessive breakdown of hemoglobin ( thalassemia ) Transfusion reaction

171

Diabetic Retinopathy and Serum Lipids  

Microsoft Academic Search

The association between serum lipid levels and diabetic retinopathy has been investigated in many studies. Some studies show a positive relationship between serum cholesterol and low-density lipoprotein levels and retinal hard exudation. Other studies show serum triglyceride levels as being important in the progression of retinopathy. Certain other studies show no relationship between serum lipid levels and diabetic retinopathy. We

K T Yeo

172

Attention Deficit/Hyperactivity Disorder and Childhood Autism in Association with Prenatal Exposure to Perfluoroalkyl Substances: A Nested Case–Control Study in the Danish National Birth Cohort  

PubMed Central

Background: Perfluoroalkyl substances (PFASs) are persistent pollutants found to be endocrine disruptive and neurotoxic in animals. Positive correlations between PFASs and neurobehavioral problems in children were reported in cross-sectional data, but findings from prospective studies are limited. Objectives: We investigated whether prenatal exposure to PFASs is associated with attention deficit/hyperactivity disorder (ADHD) or childhood autism in children. Methods: Among 83,389 mother–child pairs enrolled in the Danish National Birth Cohort during 1996–2002, we identified 890 ADHD cases and 301 childhood autism cases from the Danish National Hospital Registry and the Danish Psychiatric Central Registry. From this cohort, we randomly selected 220 cases each of ADHD and autism, and we also randomly selected 550 controls frequency matched by child’s sex. Sixteen PFASs were measured in maternal plasma collected in early or mid-pregnancy. We calculated risk ratios (RRs) using generalized linear models, taking into account sampling weights. Results: Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were detected in all samples; four other PFASs were quantified in ? 90% of the samples. We did not find consistent evidence of associations between mother’s PFAS plasma levels and ADHD [per natural log nanograms per milliliter increase: PFOS RR = 0.87 (95% CI: 0.74, 1.02); PFOA RR = 0.98 (95% CI: 0.82, 1.16)] or autism [per natural log nanograms per milliliter increase: PFOS RR = 0.92 (95% CI: 0.69, 1.22); PFOA RR = 0.98 (95% CI: 0.73, 1.31)]. We found positive as well as negative associations between higher PFAS quartiles and ADHD in models that simultaneously adjusted for all PFASs, but these estimates were imprecise. Conclusions: In this study we found no consistent evidence to suggest that prenatal PFAS exposure increases the risk of ADHD or childhood autism in children. Citation: Liew Z, Ritz B, von Ehrenstein OS, Bech BH, Nohr EA, Fei CY, Bossi R, Henriksen TB, Bonefeld-Jřrgensen EC, Olsen J. 2015. Attention deficit/hyperactivity disorder and childhood autism in association with prenatal exposure to perfluoroalkyl substances: a nested case–control study in the Danish National Birth Cohort. Environ Health Perspect 123:367–373;?http://dx.doi.org/10.1289/ehp.1408412 PMID:25616253

Liew, Zeyan; Ritz, Beate; von Ehrenstein, Ondine S.; Bech, Bodil Hammer; Nohr, Ellen Aagaard; Fei, Chunyuan; Bossi, Rossana; Henriksen, Tine Brink; Bonefeld-Jřrgensen, Eva Cecilie

2014-01-01

173

Temporal-spatial distributions and ecological risks of perfluoroalkyl acids (PFAAs) in the surface water from the fifth-largest freshwater lake in China (Lake Chaohu).  

PubMed

To investigate the residues, compositions, distributions and potential ecological risks of perfluoroalkyl acids (PFAAs), water samples were collected seasonally between August 2011 and November 2012 from 20 sites in Lake Chaohu and its tributary rivers. The mean concentration of total PFAAs (TPFAAs) was 14.46 ± 6.84 ng/L. PFOA was the predominant contaminant (8.62 ± 4.40 ng/L), followed by PFBA (2.04 ± 1.16 ng/L) and PFHxA (1.23 ± 1.50 ng/L). The TPFAAs concentrations peaked in August 2012 in each area, except for the western river. The opposite spatial trends were found for PFOA and PFOS in both the lake and river areas. Except for PFOS and PFUdA, the levels of TPFAAs and PFAAs were significantly related to the composition of fluorescent dissolved organic matter (FDOM) but not related to total DOM expressed by dissolved organic carbon (DOC). The risk of PFOS determined by a species sensitivity distribution model was notably above that of PFOA. PMID:25686885

Liu, Wen-Xiu; He, Wei; Qin, Ning; Kong, Xiang-Zhen; He, Qi-Shuang; Yang, Bin; Yang, Chen; Jorgensen, Sven Erik; Xu, Fu-Liu

2015-05-01

174

Increasing concentrations of perfluoroalkyl acids in Scandinavian otters (Lutra lutra) between 1972 and 2011: a new threat to the otter population?  

PubMed

Liver samples from 140 otters (Lutra lutra) from Sweden and Norway were analyzed for 10 perfluoroalkyl carboxylic acids (PFCAs; C6-C15), 4 perfluoroalkane sulfonic acids (PFSAs; C4,C6,C8,C10) and perfluorooctane sulfonamide (FOSA). Perfluorooctane sulfonic acid (PFOS) was the dominant compound accounting for approximately 80% of the fluorinated contaminants and showing concentrations up to 16 ?g/g wet weight. Perfluorononanoic acid (PFNA) was the dominant PFCA (up to 640 ng/g wet weight) closely followed by the C10 and C11 homologues. A spatial comparison between otters from southwestern Norway, southern and northern Sweden sampled between 2005 and 2011 revealed that the samples from southern Sweden had generally the largest contaminant load, but two PFCAs and FOSA were higher concentrated in the Norwegian samples. A temporal trend study was performed on otters from southern Sweden collected between 1972 and 2011. Seven PFCAs (C8-C14), PFOS and perfluorodecane sulfonic acid (PFDS) showed significantly increasing trends with doubling times between 5.5 and 13 years. The PFCAs also showed significantly increasing trends over the period 2002 to 2011. These findings together with the exceptionally high liver concentrations of PFOS are of great concern for the Scandinavian otter populations. PMID:24033312

Roos, Anna; Berger, Urs; Järnberg, Ulf; van Dijk, Jiska; Bignert, Anders

2013-10-15

175

Global emission inventories for C4-C14 perfluoroalkyl carboxylic acid (PFCA) homologues from 1951 to 2030, Part I: production and emissions from quantifiable sources.  

PubMed

We quantify global emissions of C4-C14 perfluoroalkyl carboxylic acid (PFCA) homologues during the life-cycle of products based on perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorooctane sulfonyl fluoride (POSF), and fluorotelomer compounds. We estimate emissions of 2610-21400 tonnes of C4-C14 PFCAs in the period from 1951 to 2015, and project 20-6420 tonnes to be emitted from 2016 to 2030. The global annual emissions steadily increased in the period 1951-2002, followed by a decrease and then another increase in the period 2002-2012. Releases from fluoropolymer production contributed most to historical PFCA emissions (e.g. 55-83% in 1951-2002). Since 2002, there has been a geographical shift of industrial sources (particularly fluoropolymer production sites) from North America, Europe and Japan to emerging Asian economies, especially China. Sources differ between PFCA homologues, sometimes considerably, and the relative contributions of each source change over time. For example, whereas 98-100% of historical (1951-2002) PFOA emissions are attributed to direct releases during the life-cycle of products containing PFOA as ingredients or impurities, a much higher historical contribution from PFCA precursor degradation is estimated for some other homologues (e.g. 9-78% for PFDA). We address the uncertainties of the PFCA emissions by defining a lower and a higher emission scenario, which differ by approximately a factor of eight. PMID:24932785

Wang, Zhanyun; Cousins, Ian T; Scheringer, Martin; Buck, Robert C; Hungerbühler, Konrad

2014-09-01

176

Are perfluoroalkyl acids in waste water treatment plant effluents the result of primary emissions from the technosphere or of environmental recirculation?  

PubMed

Wastewater treatment plants (WWTP) have been suggested to be one of the major pathways of perfluoroalkyl acids (PFAAs) from the technosphere to the aquatic environment. The origin of PFAAs in WWTP influents is either from current primary emissions or a result of recirculation of PFAAs that have been residing and transported in the environment for several years or decades. Environmental recirculation can then occur when PFAAs from the environment enter the wastewater stream in, e.g., tap water. In this study 13 PFAAs and perfluorooctane sulfonamide were analyzed in tap water as well as WWTP influent, effluent and sludge from three Swedish cities: Bromma (in the metropolitan area of Stockholm), Bollebygd and Umeĺ. A mass balance of the WWTPs was assembled for each PFAA. Positive mass balances were observed for PFHxA and PFOA in all WWTPs, indicating the presence of precursor compounds in the technosphere. With regard to environmental recirculation, tap water was an important source of PFAAs to the Bromma WWTP influent, contributing >40% for each quantified sulfonic acid and up to 30% for the carboxylic acids. The PFAAs in tap water from Bollebygd and Umeĺ did not contribute significantly to the PFAA load in the WWTP influents. Our results show that in order to estimate current primary emissions from the technosphere, it may be necessary to correct the PFAA emission rates in WWTP effluents for PFAAs present in tap water, especially in the case of elevated levels in tap water. PMID:25139477

Filipovic, Marko; Berger, Urs

2015-06-01

177

An On-Line Solid Phase Extraction-Liquid Chromatography-Tandem Mass Spectrometry Method for the Determination of Perfluoroalkyl Acids in Drinking and Surface Waters  

PubMed Central

An UHPLC-MS/MS multiresidue method based on an on-line solid phase extraction (SPE) procedure was developed for the simultaneous determination of 9 perfluorinated carboxylates (from 4 to 12 carbon atoms) and 3 perfluorinated sulphonates (from 4 to 8 carbon atoms). This work proposes using an on-line solid phase extraction before chromatographic separation and analysis to replace traditional methods of off-line SPE before direct injection to LC-MS/MS. Manual sample preparation was reduced to sample centrifugation and acidification, thus eliminating several procedural errors and significantly reducing time-consuming and costs. Ionization suppression between target perfluorinated analytes and their coeluting SIL-IS were detected for homologues with a number of carbon atoms less than 9, but the quantitation was not affected. Total matrix effect corrected by SIL-IS, inclusive of extraction efficacy, and of ionization efficiency, ranged between ?34 and +39%. The percentage of recoveries, between 76 and 134%, calculated in different matrices (tap water and rivers impacted by different pollutions) was generally satisfactory. LODs and LOQs of this on-line SPE method, which also incorporate recovery losses, ranged from 0.2 to 5.0?ng/L and from 1 to 20?ng/L, respectively. Validated on-line SPE-LC/MS/MS method has been applied in a wide survey for the determination of perfluoroalkyl acids in Italian surface and ground waters.

Mazzoni, Michela; Rusconi, Marianna; Valsecchi, Sara; Martins, Claudia P. B.; Polesello, Stefano

2015-01-01

178

Blood Serum Magnesium  

E-print Network

Key Words · Blood Serum · Magnesium · Flame · Atomic Absorption Method Guide: 40162 Atomic, and magnesium is determined by flame atomic absorption spectrometry using an air-acetylene flame. Lanthanum Magnesium master standard (7.5 mM/L) Dissolve 0.182 g of oxide-free magnesium ribbon in the minimum

Wells, Mathew G. - Department of Physical and Environmental Sciences, University of Toronto

179

Janus Serum Bank  

Cancer.gov

The Janus Serum bank was established in order to collect and store blood samples from presumably healthy individuals for future use in cancer research. The intention was to obtain information on factors important in the pathogenesis and etiology of cancer by examining blood samples obtained during the preclinical stage or latent period before the tumor has developed.

180

Polymers for electronics and chemical sensing applications  

E-print Network

The incorporation of molecular structures such as shape persistent molecular frameworks, strong hydrogen bond donor groups or perfluoro-alkyl groups can result in considerable gains in the performance of some established ...

Amara, John Paul

2006-01-01

181

How to insulate a reactive site from a perfluoroalkyl group: photoelectron spectroscopy, calorimetric, and computational studies of long-range electronic effects in fluorous phosphines P((CH(2))(m)(CF(2))(7)CF(3))(3).  

PubMed

This study advances strategy and design in catalysts and reagents for fluorous and supercritical CO(2) chemistry by defining the structural requirements for insulating a typical active site from a perfluoroalkyl segment. The vertical ionization potentials of the phosphines P((CH(2))(m)R(f8))(3) (m = 2 (2) to 5 (5)) are measured by photoelectron spectroscopy, and the enthalpies of protonation by calorimetry (CF(3)SO(3)H, CF(3)C(6)H(5)). They undergo progressively more facile (energetically) ionization and protonation (P(CH(2)CH(3))(3) > 5 > 4 approximately equal to P(CH(3))(3) > 3 > 2), as expected from inductive effects. Equilibrations of trans-Rh(CO)(Cl)(L)(2) complexes (L = 2, 3) establish analogous Lewis basicities. Density functional theory is used to calculate the structures, energies, ionization potentials, and gas-phase proton affinities (PA) of the model phosphines P((CH(2))(m)()CF(3))(3) (2'-9'). The ionization potentials of 2'-5' are in good agreement with those of 2-5, and together with PA values and analyses of homodesmotic relationships are used to address the title question. Between 8 and 10 methylene groups are needed to effectively insulate a perfluoroalkyl segment from a phosphorus lone pair, depending upon the criterion employed. Computations also show that the first carbon of a perfluoroalkyl segment exhibits a much greater inductive effect than the second, and that ionization potentials of nonfluorinated phosphines P((CH(2))(m)CH(3))(3) reach a limit at approximately nine carbons (m = 8). PMID:11841323

Jiao, Haijun; Le Stang, Sylvie; Soós, Tibor; Meier, Ralf; Kowski, Klaus; Rademacher, Paul; Jafarpour, Laleh; Hamard, Jean-Benoit; Nolan, Steven P; Gladysz, J A

2002-02-20

182

Serum sepsis, not sickness.  

PubMed

Rarely taught in medical schools, clinical reasoning is the ability to discern the important from the unimportant and to arrive at accurate and efficient clinical conclusions. Identifying errors in reasoning is difficult; however, undetected clinical reasoning errors can have exponential consequences. As quality and patient safety come into focus, identifying and preventing clinical reasoning errors have become imperative. The authors present a case of a man sent for admission from a subspecialty clinic diagnosed with infliximab-induced serum sickness. Not countering the expert's diagnosis, initial workup failed to diagnose joint abscess and sepsis. Heuristics are mental shortcuts used to make decision making more efficient but can lead to error. The anchoring heuristic, premature closure, confirmation bias and the blind obedience heuristic are examples. Introspective surveillance and interactive hypothesis testing defend against heuristics. The authors conclude by discussing 4 types of hypersensitivity reactions, serum sickness in particular, and the chimeric nature of infliximab. PMID:21273840

Guidry, Michelle M; Drennan, Robert H; Weise, Jeff; Hamm, L Lee

2011-02-01

183

The Human Serum Metabolome  

PubMed Central

Continuing improvements in analytical technology along with an increased interest in performing comprehensive, quantitative metabolic profiling, is leading to increased interest pressures within the metabolomics community to develop centralized metabolite reference resources for certain clinically important biofluids, such as cerebrospinal fluid, urine and blood. As part of an ongoing effort to systematically characterize the human metabolome through the Human Metabolome Project, we have undertaken the task of characterizing the human serum metabolome. In doing so, we have combined targeted and non-targeted NMR, GC-MS and LC-MS methods with computer-aided literature mining to identify and quantify a comprehensive, if not absolutely complete, set of metabolites commonly detected and quantified (with today's technology) in the human serum metabolome. Our use of multiple metabolomics platforms and technologies allowed us to substantially enhance the level of metabolome coverage while critically assessing the relative strengths and weaknesses of these platforms or technologies. Tables containing the complete set of 4229 confirmed and highly probable human serum compounds, their concentrations, related literature references and links to their known disease associations are freely available at http://www.serummetabolome.ca. PMID:21359215

Psychogios, Nikolaos; Hau, David D.; Peng, Jun; Guo, An Chi; Mandal, Rupasri; Bouatra, Souhaila; Sinelnikov, Igor; Krishnamurthy, Ramanarayan; Eisner, Roman; Gautam, Bijaya; Young, Nelson; Xia, Jianguo; Knox, Craig; Dong, Edison; Huang, Paul; Hollander, Zsuzsanna; Pedersen, Theresa L.; Smith, Steven R.; Bamforth, Fiona; Greiner, Russ; McManus, Bruce; Newman, John W.; Goodfriend, Theodore; Wishart, David S.

2011-01-01

184

Effects of perfluoroalkyl compounds on mRNA expression levels of thyroid hormone-responsive genes in primary cultures of avian neuronal cells.  

PubMed

There is growing interest in assessing the neurotoxic and endocrine disrupting potential of perfluoroalkyl compounds (PFCs). Several studies have reported in vitro and in vivo effects related to neuronal development, neural cell differentiation, prenatal and postnatal development and behavior. PFC exposure altered hormone levels and the expression of hormone-responsive genes in mammalian and aquatic species. This study is the first to assess the effects of PFCs on messenger RNA (mRNA) expression in primary cultures of neuronal cells in two avian species: the domestic chicken (Gallus domesticus) and herring gull (Larus argentatus). The following thyroid hormone (TH)-responsive genes were examined using real-time reverse transcription-PCR: type II iodothyronine 5'-deiodinase (D2), D3, transthyretin (TTR), neurogranin (RC3), octamer motif-binding factor (Oct-1), and myelin basic protein. Several PFCs altered the mRNA expression levels of genes associated with the TH pathway in avian neuronal cells. Short-chained PFCs (less than eight carbons) altered the expression of TH-responsive genes (D2, D3, TTR, and RC3) in chicken embryonic neuronal cells to a greater extent than long-chained PFCs (more than or equal to eight carbons). Variable transcriptional changes were observed in herring gull embryonic neuronal cells exposed to short-chained PFCs; mRNA levels of Oct-1 and RC3 were upregulated. This is the first study to report that PFC exposure alters mRNA expression in primary cultures of avian neuronal cells and may provide insight into the possible mechanisms of action of PFCs in the avian brain. PMID:21212296

Vongphachan, Viengtha; Cassone, Cristina G; Wu, Dongmei; Chiu, Suzanne; Crump, Doug; Kennedy, Sean W

2011-04-01

185

Perfluoroalkyl substances in soft tissues and tail feathers of Belgian barn owls (Tyto alba) using statistical methods for left-censored data to handle non-detects.  

PubMed

Perfluoroalkyl substances (PFASs) were investigated in tail feathers and soft tissues (liver, muscle, preen gland and adipose tissue) of barn owl (Tyto alba) road-kill victims (n=15) collected in the province of Antwerp (Belgium). A major PFAS producing facility is located in the Antwerp area and levels of PFASs in biota from that region have been found to be very high in previous studies. We aimed to investigate for the first time the main sources of PFASs in feathers of a terrestrial bird species. Throughout this study, we have used statistical methods for left-censored data to cope with levels below the limit of detection (LOD), instead of traditional, potentially biased, substitution methods. Perfluorooctane sulfonate (PFOS) was detected in all tissues (range: 11ng/g ww in muscle-1208ng/g ww in preen oil) and in tail feathers (<2.2-56.6ng/g ww). Perfluorooctanoate (PFOA) was measured at high levels in feathers (<14-670ng/g ww), but not in tissues (more than 50%

Jaspers, Veerle L B; Herzke, Dorte; Eulaers, Igor; Gillespie, Brenda W; Eens, Marcel

2013-02-01

186

Emission of perfluoroalkyl carboxylic acids (PFCA) from heated surfaces made of polytetrafluoroethylene (PTFE) applied in food contact materials and consumer products.  

PubMed

Polytetrafluoroethylene (PTFE) has been widely discussed as a source of perfluorooctanoic acid (PFOA), which has been used in the production of fluoropolymers. PTFE may also contain unintended perfluoroalkyl carboxylic acids (PFCAs) caused by thermolysis of PTFE, which has been observed at temperatures above 300°C. Common PTFE coated food contact materials and consumer goods are operated at temperatures above 200°C. However, knowledge on possible emissions of PFCAs is limited. Therefore, it was the aim of this study to investigate and evaluate the emission of PFCAs from PTFE coated products with both, normal use and overheating scenarios. Four pans, claimed to be PFOA free, and nine consumer products were investigated. At normal use conditions (<230°C), emissions from PTFE surfaces were trapped for 1h. Overheating scenarios (>260°C) recorded emissions during a 30min heating of empty pans on a stove. Emissions were analyzed by LC-ESI-MS. Results indicate the emission of PFCAs, whereas no perfluorinated sulfonic acids were traced. At normal use conditions total emissions of PFCAs accounted for 4.75ng per hour. Overheated pans, however, released far higher amounts with up to 12190ng PFCAs per hour at 370°C. Dominating contributors where PFBA and PFOA at normal use and PFBA and PFPeA during overheating. Temperature seems to be the main factor controlling the emission of PFCAs. A worst case estimation of human exposure revealed that emissions of PFCAs from heated PTFE surfaces would be far below the TDI of 1500ng PFOA per kg body weight. PMID:25496745

Schlummer, Martin; Sölch, Christina; Meisel, Theresa; Still, Mona; Gruber, Ludwig; Wolz, Gerd

2015-06-01

187

Historical usage of aqueous film forming foam: A case study of the widespread distribution of perfluoroalkyl acids from a military airport to groundwater, lakes, soils and fish.  

PubMed

Historical usage of aqueous film forming foams (AFFFs) at military airports is a potential source of perfluoroalkyl acids (PFAAs) to the nearby environment. In this study, the distribution of perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorohexane sulfonate (PFHxS) and perfluorooctane sulfonate (PFOS) in soil, groundwater, surface water, tap water well, and fish muscle was investigated at a closed down military airfield (F18) and its surroundings in Stockholm, Sweden. The presence of PFOS at AFFF training sites was inventoried. One major finding of the study is that a former airfield, abandoned since 1994, may still be a point source of PFAAs to nearby recipients. PFOS and PFOA were ubiquitous in the soil samples at former AFFF training sites with concentrations ranging from 2.18 to 8520ngg(-1) dry weight and <0.12-287ngg(-1) dry weight respectively. The sum of PFAAs in the groundwater and surface waters ranged from 738 to 51000ngL(-1) and

Filipovic, Marko; Woldegiorgis, Andreas; Norström, Karin; Bibi, Momina; Lindberg, Maria; Österĺs, Ann-Helen

2015-06-01

188

Discovery of C5-C17 Poly- and Perfluoroalkyl Substances in Water by In-Line SPE-HPLC-Orbitrap with In-Source Fragmentation Flagging.  

PubMed

The presence of unknown organofluorine compounds in environmental samples has prompted the development of nontargeted analytical methods capable of detecting new perfluoroalkyl and polyfluoroalkyl substances (PFASs). By combining high volume injection with high performance liquid chromatography (HPLC) and ultrahigh resolution Orbitrap mass spectrometry, a sensitive (0.003-0.2 ng F/mL for model mass-labeled PFASs) untargeted workflow was developed for discovery and characterization of novel PFASs in water. In the first step, up to 5 mL of water is injected to in-line solid phase extraction, chromatographed by HPLC, and detected by electrospray ionization with mass spectral acquisition in parallel modes cycling back and forth: (i) full scan with ultrahigh resolving power (RP = 120,000, mass accuracy ?3 ppm), and (ii) in-source fragmentation flagging scans designed to yield marker fragment ions including [C2F5](-) (m/z 118.992), [C3F7](-) (m/z 168.988), [SO4H](-) (m/z 96.959), and [Cl](-) (m/z 34.9). For flagged PFASs, plausible empirical formulas were generated from accurate masses, isotopic patterns, and fragment ions. In the second step, another injection is made to collect high resolution MS/MS spectra of suspect PFAS ions, allowing further confirmation of empirical formulas while also enabling preliminary structural characterization. The method was validated by applying it to an industrial wastewater, and 36 new PFASs were discovered. Of these, 26 were confidently assigned to 3 new PFAS classes that have not previously been reported in the environment: polyfluorinated sulfates (CnFn+3Hn-2SO4(-); n = 5, 7, 9, 11, 13, and 15), chlorine substituted perfluorocarboxylates (ClCnF2nCO2(-); n = 4-11), and hydro substituted perfluorocarboxylates (HCnF2nCO2(-); n = 5-16). Application of the technique to environmental water samples is now warranted. PMID:25818392

Liu, Yanna; Pereira, Alberto Dos Santos; Martin, Jonathan W

2015-04-21

189

ACTIVATION ASSAY FOR PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR- ALPHA (PPARÁ) BY PERFLUOROALKYL ACIDS (PFAAS) IN COS-1 CELLS  

EPA Science Inventory

PFAAs have been found to elicit various physiological effects including peroxisome proliferation, indicating the mechanism of action for these chemicals could involve PPAR. This study investigates the ability of PFAAs to bind and activate mouse and human PPAR? in COS-1 cell...

190

Is the fresh water fish consumption a significant determinant of the internal exposure to perfluoroalkylated substances (PFAS)?  

PubMed

PFAS are man-made compounds that are highly spread in the environment. Human dietary exposure to such contaminants is of high concern as they may accumulate in the food chain. Different studies already demonstrated the importance of the fish consumption in the dietary exposure of these molecules and the potential increase of internal doses of PFAS following the consumption of PFAS. However, so far few study aimed to study the link between the consumption of fresh water fishes and the internal exposure to PFAS. Objectives of this study were (i) to estimate the internal exposure of populations that are potentially high consumers of fresh water fishes and (ii) to determine whether the consumption of fish caught from fresh water is a significant determinant of the internal exposure of PFAS. In this work, a large sample of adult freshwater anglers from the French metropolitan population (478 individuals) was constituted randomly from participants lists of anglers associations. Questionnaires provided social and demographic information and diet information for each subject. In addition, analyses of blood serum samples provided the internal concentration of 14 PFAS. The survey design allowed to extrapolate the data obtained on the 478 individuals to the freshwater angler population. Descriptive data regarding internal levels of PFAS were discussed at the population level, whereas identification of the determinants were done at the 478 individuals level as sufficient contrast was required in terms of fresh water fish consumption. Only molecules for which the detection frequency were above 80% in blood were considered, i.e., PFOS, PFOA, PFHxS, PFNA, PFHpS, and PFDA. Distribution profiles showed log-normal distribution and PFOS and PFOA were the main contributors of the PFAS sum. For PFOS, the results obtained on the 478 individuals showed that upper percentiles were higher as compared to upper percentiles obtained on occidental general population. This confirmed an over-exposure of a fraction of the 478 individuals. Though, when the results were considered at the population level, the values were close. This was attributed to the low consumption frequency of fresh water fish in the general population. For PFOS, PFNA, PFHxS, PFHpS and PFDA, the fresh water fish consumption was identified as one of the contributors of internal PFAS concentrations. Gender, age, geographical location and consumption of home-grown products as other determinants were also discussed in this paper. PMID:25091270

Denys, Sébastien; Fraize-Frontier, Sandrine; Moussa, Oumar; Le Bizec, Bruno; Veyrand, Bruno; Volatier, Jean-Luc

2014-12-01

191

Serum vitamin c and iron levels in oral submucous fibrosis  

PubMed Central

Background: In this study Serum Vitamin C and Iron levels in Oral submucous fibrosis (OSMF) were estimated. The objective was to evaluate the correlation between Serum Vitamin C and Iron levels in OSMF individuals. Serum Iron content can be a predictor for the progression of this condition. OSMF is basically a disorder of collagen metabolism where Vitamin C gets utilized in conversion of proline into hydroxyproline, this hydroxylation reaction requires ferrous Iron and Vitamin C. Many studies regarding micronutrients and other antioxidants levels have been emphasized, but very few studies are done on the Serum levels of Vitamin C and its correlation with Iron in OSMF patients. Methods: Thirty five OSMF patients and 50 deleterious habit free healthy individuals (controls) were selected. Two ml of venous blood was collected from each individual. Vitamin C level in serum was estimated by 2-4 dinitrophenylhydrazine method and Iron estimated by Tripyridyl method. Results: The level of Serum Vitamin-C and Iron was significantly decreased in OSMF patients when compared to controls which were statistically significant. Conclusion: On the basis of these observations, it seems possible that the chemical, thermal and/or mechanical factors associated with the use of areca nut may act in conjunction with the Vitamin C and Iron deficiency leading to the development of OSMF. Therapeutic substitution of vitamin C and Iron may be recommended in the management of OSMF PMID:25565730

Guruprasad, R; Nair, Preeti P; Singh, Manika; Singh, Manishi; Singh, MP; Jain, Arpit

2014-01-01

192

Binding of aluminum to human serum transferrin, human serum albumin and rat serum proteins  

SciTech Connect

Human serum transferrin (HSTF), human serum albumin (HSA) and rat serum were compared for their interaction with AlCl[sub 3], in a Tris-HCl buffer solutions. The AlCl[sub 3] was tested in series of concentrations in the range of 50 [mu]M up to 500 [mu]M. HSTF, HSA and their 1:1 mixture and rat serum were incubated at 37 C with series of AlCl[sub 3] concentrations. The protein profile of the incubated solutions were compared to control using SDS-PAGE and FPLC tests. The results indicated that HSTF was more specifically responsive to AlCl[sub 3] showing a characteristic increase in it UV absorption, peak and area dimensions. Simultaneously, HSA was less affected, but it showed a significant shift with an increase in molecular weight accompanied with a change in its profile. The respective bands of transferrin and albumin in rat serum behaved similarly.

El-Sebae, A.K.H.; Zeid, M.M.A.; Abdel-Rahman, F.H.; Saleh, M.A. (Texas Southern Univ., Houston, TX (United States). Environmental Chemistry and Toxicology Lab.)

1994-01-01

193

Operation of a DNA-Based Autocatalytic Network in Serum  

NASA Astrophysics Data System (ADS)

The potential for inferring the presence of cancer by the detection of miRNA in human blood has motivated research into the design and operation of DNA-based chemical amplifiers that can operate in bodily fluids. As a first step toward this goal, we have tested the operation of a DNA-based autocatalytic network in human serum and mouse serum. With the addition of sodium dodecyl sulfate to prevent degradation by nuclease activity, the network was found to operate successfully with both DNA and RNA catalysts.

Graugnard, Elton; Cox, Amber; Lee, Jeunghoon; Jorcyk, Cheryl; Yurke, Bernard; Hughes, William L.

194

Sequences Of Amino Acids For Human Serum Albumin  

NASA Technical Reports Server (NTRS)

Sequences of amino acids defined for use in making polypeptides one-third to one-sixth as large as parent human serum albumin molecule. Smaller, chemically stable peptides have diverse applications including service as artificial human serum and as active components of biosensors and chromatographic matrices. In applications involving production of artificial sera from new sequences, little or no concern about viral contaminants. Smaller genetically engineered polypeptides more easily expressed and produced in large quantities, making commercial isolation and production more feasible and profitable.

Carter, Daniel C.

1992-01-01

195

Photocatalytic degradation of some methyl perfluoroalkyl ethers on TiO{sub 2} particles in air: The dependence on the dark-adsorption, the products, and the implication for a possible tropospheric sink  

SciTech Connect

Fluorinated ethers are potential substitutes for hydrochlorofluorocarbons and hydrofluorocarbons. Their lifetime through each removal process should be evaluated to estimate their effects on the environment as GWP. Photocatalytic reactions on titanium dioxide particles were examined as a possible tropospheric sink through heterogeneous processes on particulate matters. Photocatalytic degradation of three kinds of methyl perfluoroalkyl ethers in air takes place on titanium dioxide particles at ambient temperature under illumination of light. Main products are carbon dioxide and carbonyl fluoride. The initial photodegradation rate is proportional to the square root of the amount of fluorinated ethers adsorbed in the dark, while the adsorption shows a Henry type adsorption curve. A tentative reaction scheme via H atom abstraction and a formic ester is proposed. The kinetic data indicates that the heterogeneous photodegradation could proceed with a rate enough to serve as a tropospheric sink of fluorinated ethers even in such low density of titanium dioxide particles as in the environment.

Kutsuna, Shuzo; Takeuchi, Koji; Ibusuki, Takashi [National Inst. for Resources and Environment, Tsukuba, Ibaraki (Japan). Global Warming Control Dept.] [National Inst. for Resources and Environment, Tsukuba, Ibaraki (Japan). Global Warming Control Dept.; Toma, Mitsuhiro [Research Inst. of Innovative Technology for the Earth, Tsukuba, Ibaraki (Japan). New Refrigerants Development Group] [Research Inst. of Innovative Technology for the Earth, Tsukuba, Ibaraki (Japan). New Refrigerants Development Group

1999-04-01

196

Evidence for the involvement of xenobiotic-responsive nuclear receptors in transcriptional effects upon perfluoroalkyl acid exposure in diverse species.  

PubMed

Humans and ecological species have been found to have detectable body burdens of a number of perfluorinated alkyl acids (PFAA) including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). In mouse and rat liver these compounds elicit transcriptional and phenotypic effects similar to peroxisome proliferator chemicals (PPC) that work through the nuclear receptor peroxisome proliferator-activated receptor alpha (PPAR alpha). Recent studies indicate that along with PPAR alpha other nuclear receptors are required for transcriptional changes in the mouse liver after PFOA exposure including the constitutive activated receptor (CAR) and pregnane X receptor (PXR) that regulate xenobiotic metabolizing enzymes (XME). To determine the potential role of CAR/PXR in mediating effects of PFAAs in rat liver, we performed a meta-analysis of transcript profiles from published studies in which rats were exposed to PFOA or PFOS. We compared the profiles to those produced by exposure to prototypical activators of CAR, (phenobarbital (PB)), PXR (pregnenolone 16 alpha-carbonitrile (PCN)), or PPAR alpha (WY-14,643 (WY)). As expected, PFOA and PFOS elicited transcript profile signatures that included many known PPAR alpha target genes. Numerous XME genes were also altered by PFOA and PFOS but not WY. These genes exhibited expression changes shared with PB or PCN. Reexamination of the transcript profiles from the livers of chicken or fish exposed to PFAAs indicated that PPAR alpha, CAR, and PXR orthologs were not activated. Our results indicate that PFAAs under these experimental conditions activate PPAR alpha, CAR, and PXR in rats but not chicken and fish. Lastly, we discuss evidence that human populations with greater CAR expression have lower body burdens of PFAAs. PMID:19162173

Ren, Hongzu; Vallanat, Beena; Nelson, David M; Yeung, Leo W Y; Guruge, Keerthi S; Lam, Paul K S; Lehman-McKeeman, Lois D; Corton, J Christopher

2009-06-01

197

Serum transferrin receptor.  

PubMed

Transferrin receptors (TfRs) are the conventional pathway by which cells acquire iron for physiological requirements. Under iron-deficient conditions there is an increased concentration of surface TfR, especially on bone marrow erythroid precursors, as a mechanism to sequester needed iron. TfRs are also present in the circulation, and the circulating serum TfR (sTfR) level reflects total body TfR concentration. Under normal conditions erythroid precursors are the main source of sTfR. Disorders of the bone marrow with reduced erythroid precursors are associated with low sTfR levels. The sTfR concentration begins to rise early in iron deficiency with the onset of iron-deficient erythropoiesis, and continues to rise as iron-deficient erythropoiesis progressively worsens, prior to the development of anemia. The sTfR level does not increase in anemia of chronic inflammation, but is increased when anemia of chronic inflammation is combined with iron deficiency. The sTfR level is also increased in patients with expanded erythropoiesis, including hemolytic anemias, myelodysplastic syndromes, and use of erythropoietic stimulating agents. The ratio of sTfR/ferritin can be used to quantify the entire spectrum of iron status from positive iron stores through negative iron balance, and is particularly useful in evaluating iron status in population studies. The sTfR/log ferritin ratio is valuable for distinguishing anemia of chronic inflammation from iron deficiency anemia, whether the latter occurs alone or in combination with anemia of chronic inflammation. PMID:18821709

Skikne, Barry S

2008-11-01

198

Serum Metabolomic Biomarkers of Dementia  

PubMed Central

Aims: This study compared serum metabolites of demented patients (Alzheimer's disease and vascular dementia) and controls, and explored serum metabolite profiles of nondemented individuals 5 years preceding the diagnosis. Methods: Cognitively healthy participants were followed up for 5-20 years. Cognitive assessment, serum sampling, and diagnosis were completed every 5 years. Multivariate analyses were conducted on the metabolite profiles generated by gas chromatography/time-of-flight mass spectrometry. Results: A significant group separation was found between demented patients and controls, and between incident cases and controls. Metabolites that contributed in both analyses were 3,4-dihydroxybutanoic acid, docosapentaenoic acid, and uric acid. Conclusions: Serum metabolite profiles are altered in demented patients, and detectable up to 5 years preceding the diagnosis. Blood sampling can make an important contribution to the early prediction of conversion to dementia. PMID:25177334

Mousavi, Malahat; Jonsson, Pär; Antti, Henrik; Adolfsson, Rolf; Nordin, Annelie; Bergdahl, Jan; Eriksson, Kĺre; Moritz, Thomas; Nilsson, Lars-Göran; Nyberg, Lars

2014-01-01

199

Serum Matrix Metalloproteinase Levels in Patients Exposed to Sulfur Mustard  

PubMed Central

Background: Matrix metalloproteinases (MMPs) are a group of endopeptidases which comprised of various types. These proteolytic enzymes are zinc-dependent and play role in degradation of extracellular matrix (ECM). Various types of cells such as macrophages, fibroblasts, neutrophils, synovial cells and some epithelial cells secrete MMPs. According to previous studies on bronchiolitis and respiratory tract lesions in these patients and unknown pathophysiology mechanism up to date, this cross–sectional study was performed. Objectives: The aim of this study was to compare the serum MMP level in patients with chemical injuries and normal people and also determine the role of these parameters in pulmonary disorders . Materials and Methods: In this cross–sectional study, 25 Iranian patients exposed to the sulfur mustard and 25 unexposed participants as the control group were enrolled. Serum samples were collected from two groups and stored at -70?C until the measurement of MMPs and TIMPs. ELISA kit was used for measurement of MMP and TIMP based on the kit's instruction. For validations in measurement, all samples were analyzed duplicate and in some cases triplicate. Results: The mean level of MMP-9 in serum of chemically-injured group was 1592.42 and this amount in normal group was 679.72 .So there was a significant difference between two groups (P = 0.001) and the mean level of MMP-8 in serum of patients group was 49.10 and in normal group was 35.53. Then there was no significant difference between two groups (P = 0.197). The mean levels of MMP-1 and MMP-2 was not significantly different (P value > 0.05) in the patient and normal groups. And also the mean levels of TIMP-1 and TIMP-2 was not significantly different (P > 0.05) in the patients and normal groups. Conclusions: In summary, serum MMPs in chemically-injured has shown no significant difference with normal people except for the MMP-9. PMID:24829780

Shohrati, Majid; Haji Hosseini, Reza; Esfandiari, Malek Ashtar; Najafian, Nastaran; Najafian, Bita; Golbedagh, Abbas

2014-01-01

200

Evaluation of serum and salivary lipid profile: A correlative study  

PubMed Central

Context: The correlation of serum and salivary lipid profile has been poorly characterized. The most commonly used laboratory diagnostic procedures for lipid profile involve analysis of cellular and chemical constituents of blood/plasma. As a diagnostic aid, saliva offers many advantages over serum. Aims: To evaluate and compare the serum and salivary lipid profile levels in healthy individuals and to validate the role of saliva as a non-invasive diagnostic tool for assessing lipid profile. Settings and Design: The present study was a prospective study. Materials and Methods: A total of 100 healthy study subjects who had no complaint or any major illness in recent past were selected. The parameters assessed included serum and salivary: total cholesterol (TC), high-density lipoprotein-cholesterol (HDLC), low-density lipoprotein-cholesterol (LDLC), very low-density lipoprotein-cholesterol (VLDLC) and triglycerides (TGL). Statistical Analysis Used: Evaluation of results and statistical analysis was carried out using descriptive, correlation and regression analysis. Results: There was a moderate level of correlation between serum and salivary TC, TGL, HDLC and VLDLC and there was a low and quite small correlation between serum and salivary LDLC. For all the five parameters assessed as a part of lipid profile, the correlation coefficients were highly significant statistically and also, with an increase in the serum mean values, corresponding increase in the saliva mean values for all the five parameters was noted. Conclusions: From the present study we conclude that saliva can be used as a non-invasive diagnostic tool for assessing lipid profile. PMID:24959029

Singh, Simranjit; Ramesh, Venkatapathy; Oza, Nirima; Balamurali, Pennagaram Dhanasekaran; Prashad, Karthikshree Vishnu; Balakrishnan, Premalatha

2014-01-01

201

Brain region-specific perfluoroalkylated sulfonate (PFSA) and carboxylic acid (PFCA) accumulation and neurochemical biomarker Responses in east Greenland polar Bears (Ursus maritimus).  

PubMed

Perfluoroalkyl substances (PFASs) is a growing class of contaminants in the Arctic environment, and include the established perfluorinated sulfonates (PFSAs; especially perfluorooctane sulfonate (PFOS)) and carboxylic acids (PFCAs). PFSAs and PFCAs of varying chain length have been reported to bioaccumulate in lipid rich tissues of the brain among other tissues such as liver, and can reach high concentrations in top predators including the polar bear. PFCA and PFSA bioaccummulation in the brain has the potential to pose neurotoxic effects and therefore we conducted a study to investigate if variations in neurochemical transmitter systems i.e. the cholinergic, glutaminergic, dopaminergic and GABAergic, could be related to brain-specific bioaccumulation of PFASs in East Greenland polar bears. Nine brain regions from nine polar bears were analyzed for enzyme activity (monoamine oxidase (MAO), acetylcholinesterase (AChE) and glutamine synthetase (GS)) and receptor density (dopamine-2 (D2), muscarinic cholinergic (mAChR) and gamma-butyric acid type A (GABA-A)) along with PFSA and PFCA concentrations. Average brain ?PFSA concentration was 25ng/g ww where PFOS accounted for 91%. Average ?PFCA concentration was 88ng/g ww where PFUnDA, PFDoDA and PFTrDA combined accounted for 79%. The highest concentrations of PFASs were measured in brain stem, cerebellum and hippocampus. Correlative analyses were performed both across and within brain regions. Significant positive correlations were found between PFASs and MAO activity in occipital lobe (e.g. ?PFCA; rp=0.83, p=0.041, n=6) and across brain regions (e.g. ?PFCA; rp=0.47, p=0.001, ?PFSA; rp=0.44, p>0.001; n=50). GABA-A receptor density was positively correlated with two PFASs across brain regions (PFOS; rp=0.33, p=0.02 and PFDoDA; rp=0.34, p=0.014; n=52). Significant negative correlations were found between mAChR density and PFASs in cerebellum (e.g. ?PFCA; rp=-0.95, p=0.013, n=5) and across brain regions (e.g. ?PFCA; rp=-0.40, p=0.003, ?PFSA; rp=-0.37, p=0.007; n=52). AChE activity and D2 density were negatively correlated with single PFCAs in several brain regions, whereas GS activity was positively correlated with PFASs primarily in occipital lobe. Results from the present study support the hypothesis that PFAS concentrations in polar bears from East Greenland have exceeded the threshold limits for neurochemical alterations. It is not known whether the observed alterations in neurochemical signaling are currently having negative effects on neurochemistry in East Greenland polar bears. However given the importance of these systems in cognitive processes and motor function, the present results indicate an urgent need for a better understanding of neurochemical effects of PFAS exposure to wildlife. PMID:25682255

Eggers Pedersen, Kathrine; Basu, Niladri; Letcher, Robert; Greaves, Alana K; Sonne, Christian; Dietz, Rune; Styrishave, Bjarne

2015-04-01

202

Duration of breastfeeding and serum PCB 153 concentrations in children.  

PubMed

Polychlorinated biphenyls (PCBs) are toxic, persistent, and bioaccumulative chemicals which, because of their lipophilic properties, are abundant in human breast milk. Breastfed infants are therefore at risk of being exposed to considerable amounts of PCBs. The commonly used exposure estimations, based solely on breast milk PCB levels and duration of breastfeeding, may lead to exposure misclassification. To improve assessments of exposure to PCBs, we determined PCB 153 serum concentration, as a model substance for PCBs, at the critical time of weaning for each child in 305 breastfed infants from 5 single time point concentration measurements spread over 7 years and data on duration of breastfeeding, using an earlier developed model of the system type. We approximated the dependence of PCB 153 serum concentration, Ctbf, adjusted to cord serum concentration, C0, on nursing period, by a polynomial function Ctbf/C0=0.596+0.278t-0.0047t(2) which reliably predicts exposure to PCB 153 of breastfed infants, important for assessment of dose-outcome relationships. Adjustment of current serum concentrations to cord serum concentration improved validity of exposure assessment. PMID:25460618

Lancz, Kinga; Hertz-Picciotto, Irva; Jusko, Todd A; Murínová, Lubica; Wimmerová, So?a; Sov?íková, Eva; Dedík, Ladislav; Strémy, Maximilián; Drobná, Beata; Farkašová, Dana; Trnovec, Tomáš

2015-01-01

203

Chemotactic Factor Inactivator in Normal Human Serum  

PubMed Central

Normal human serum contains an inactivator of chemotactic factors for neutrophilic leukocytes. The chemotactic factor inactivator (CF-I) remains soluble when serum is fractionated with ammonium sulfate (at 45% saturation), directly and irreversibly inactivates chemotactic factors, and it has a broad spectrum of activity as indicated by its inactivation of the chemotactic fragments of human C3 and C5 (third and fifth components of complement), C5?6?7?, and the bacterial chemotactic factor derived from Escherichia coli. CF-I appears as a biphasic activity according to preparative techniques of sucrose density ultracentrifugation, electrophoresis, and gel filtration. Studies on the interaction of CF-I with the radiotagged C5 chemotactic fragment fail to reveal evidence for irreversible binding as the basis for inactivation. CF-I varies from the anaphylatoxin inactivator in several physical-chemical respects, but evidence does not permit a conclusive statement about the relationship of the two inactivators. CF-I may function as a regulator of inflammatory responses. PMID:4121701

Berenberg, Jeffrey L.; Ward, Peter A.

1973-01-01

204

Serum ferritin in thalassemia intermedia.  

PubMed

Serum ferritin is a useful monitoring tool for iron overload in thalassemia major. In resource poor settings access to modalities for assessment of iron overload are limited. This study was undertaken to assess the efficiency and usefulness of serum ferritin level in thalassemia intermedia (TI) patients. This was a cross sectional observational study. Seventy seven TI patients attending the pediatric hematology clinic were included. Fasting blood sample was taken from each patient in iron free vials for iron studies. Serum ferritin was estimated by immunometric enzyme immunoassay using Orgentec GmbH kits. Mean age of patients evaluated was 10.9 ± 5.03 (3-26) years. The mean age at diagnosis was 4.21 ± 2.3 (0.8-11) years. Mean serum ferritin was 486.54 ± 640.0 ng/ml (15-4,554). Thirty two (41.5 %) patients had a ferritin value of ?500 ng/ml. Nine patients had a serum ferritin of ?1,000 ng/ml. Three of the subjects with a ferritin >1,000 ng/ml had never received a blood transfusion (BT) and in the other six, the number of BTs ranged from 1 to 8. Serum ferritin did not correlate with age, total number of BTs splenectomy status or BT in last one year (p > 0.05). In 41.5 % of TI patients, serum ferritin was ?500 ng/ml. Age, BT and splenectomized status did not affect ferritin level. We postulate interplay of other biological factors like HFE gene mutation, ferroportin, etc. to contribute to ferritin level and hence iron load in TI patients. Ferritin can possibly be used as screening and monitoring tool for iron load in TI patients when other modalities to assess iron overload are not easily available. PMID:25435728

Shah, Ravi; Trehan, Amita; Das, Reena; Marwaha, R K

2014-12-01

205

Human growth hormone expressed in tobacco cells as an arabinogalactan-protein fusion glycoprotein has a prolonged serum life  

Microsoft Academic Search

Therapeutic proteins with molecular weights lower than 40 kDa often have short serum half-lives due to their susceptibility\\u000a to serum proteases and rapid renal clearance. Chemical derivatization, such as PEGylation, or expression as serum albumin\\u000a fusions increases molecular mass and overcome these problems but at the expense of decreased bioactivity. Here we applied\\u000a a new method that yields biologically potent recombinant

Jianfeng Xu; Shigeru Okada; Li Tan; Kenneth J. Goodrum; John J. Kopchick; Marcia J. Kieliszewski

2010-01-01

206

Evaluation of potential health effects associated with serum polychlorinated biphenyl levels  

SciTech Connect

In late 1983, we conducted a cross-sectional epidemiologic study to evaluate persons at risk of exposure to three chemical waste sites by comparing clinical disease end points and clinical chemistry parameters with serum polychlorinated biphenyls (PCB) levels. A total of 106 individuals participated in the study. The only statistically significant finding in regard to self-reported, physician-diagnosed health problems was a dose-response relationship between serum PCB levels and the occurrence of high blood pressure; however, this association failed to achieve statistical significance when we controlled for possible confounding effects of both age and smoking. Serum triglyceride and cholesterol levels were also higher in the group with elevated serum PCBs; additionally, there were isolated statistically significant correlations of serum aspartate aminotransferase (SGOT) with serum lipid fraction-adjusted PCB level and serum albumin and total bilirubin with serum PCB level. Although the ranges of serum levels reported herein from exposures to PCBs in the general environment are lower than those that have been associated with acute symptoms or illness in other studies, whether these levels are associated with long-term health risks is not known. Associations of such chronic, low-dose exposures with observable health effects as suggested by this study must be evaluated further before any final conclusions can be drawn.

Stehr-Green, P.A.; Welty, E.; Steele, G.; Steinberg, K.

1986-12-01

207

Serum Fluoride and Sialic Acid Levels in Osteosarcoma  

Microsoft Academic Search

Osteosarcoma is a rare malignant bone tumor most commonly occurring in children and young adults presenting with painful swelling.\\u000a Various etiological factors for osteosarcoma are ionizing radiation, family history of bone disorders and cancer, chemicals\\u000a (fluoride, beryllium, and vinyl chloride), and viruses. Status of fluoride levels in serum of osteosarcoma is still not clear.\\u000a Recent reports have indicated that there

R. Sandhu; H. Lal; Z. S. Kundu; S. Kharb

208

A New Anti-Ag Serum (Serum B.N.)  

Microsoft Academic Search

DURING an investigation of sera from about 200 polytransfused individuals (collected at the City of Stockholm Blood Transfusion Centre), one serum (from patient B. N.) was found which formed precipitates with 230 (93.9 per cent) of 245 sera from unrelated individuals living in the Stockholm area. This patient suffers from severe haemophilia A and has received forty-five transfusions since 1943.

Jan Hirschfeld; PETER UNGER; OLOF RAMGREN

1966-01-01

209

Relationships of Perfluorooctanoate and Perfluorooctane Sulfonate Serum Concentrations between Mother–Child Pairs in a Population with Perfluorooctanoate Exposure from Drinking Water  

PubMed Central

Background: There are limited data on the associations between maternal or newborn and child exposure to perfluoroalkyl acids (PFAAs), including perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS). This study provides an opportunity to assess the association between PFAA concentrations in mother–child pairs in a population exposed to PFOA via drinking water. Objectives: We aimed to determine the relationship between mother–child PFAA serum concentrations and to examine how the child:mother ratio varies with child’s age, child’s sex, drinking-water PFOA concentration, reported bottled water use, and mother’s breast-feeding intention. Methods: We studied 4,943 mother–child pairs (children, 1–19 years of age). The child:mother PFAA ratio was stratified by possible determinants. Results are summarized as geometric mean ratios and correlation coefficients between mother–child pairs, overall and within strata. Results: Child and mother PFOA and PFOS concentrations were correlated (r = 0.82 and 0.26, respectively). Up to about 12 years of age, children had higher serum PFOA concentrations than did their mothers. The highest child:mother PFOA ratio was found among children ? 5 years (44% higher than their mothers), which we attribute to in utero exposure and to exposure via breast milk and drinking water. Higher PFOS concentrations in children persisted until at least 19 years of age (42% higher than their mothers). Boys > 5 years of age had significantly higher PFOA and PFOS child:mother ratios than did girls. Conclusion: Concentrations of both PFOA and PFOS tended to be higher in children than in their mothers. This difference persisted until they were about 12 years of age for PFOA and at least 19 years of age for PFOS. PMID:22271837

Lopez-Espinosa, Maria-Jose; Armstrong, Ben; Stein, Cheryl R.; Fletcher, Tony

2012-01-01

210

Chemical Peels  

MedlinePLUS

... How to Choose the Best Skin Care Products Chemical Peels Uses for Chemical Peels Learn more about specific conditions where chemical ... damaged skin Sagging skin Wrinkles What is a chemical peel? A chemical peel is a technique used ...

211

Analytical challenges hamper perfluoroalkyl research  

Microsoft Academic Search

The growing concern over these organohalogens, some of which have been found in human blood and appear to be widespread in the environment, led researchers to gather in Hamburg, Germany, in 2003 to evaluate the current state of methods to analyze for the organic contaminants. Jonathan Martin of the University of Toronto and 20 colleagues from industry, government, and academia

J. W. Martin; K. Kannan; U. Berger; Voogt de P; J. Field; J. Franklin; J. P. Giesy; T. Harner; D. C. G. Muir; B. Scott; M. Kaiser; U. Jarnberg; K. C. Jones; S. A. Mabury; H. Schroeder; M. Simcik; C. Sottani; Bavel Van B; A. Karrman; G. Lindstrom; Leeuwen Van S

2004-01-01

212

Improved perfluoroalkyl ether fluid development  

NASA Technical Reports Server (NTRS)

The feasibility of transforming a commercial linear perfluoroalkylether fluid into a material stable in the presence of metals and metal alloys in oxidizing atmospheres at 300 C without the loss of the desirable viscosity temperature characteristics was determined. The approach consisted of thermal oxidative treatment in the presence of catalyst to remove weak links, followed by transformation of the created functional groups into phospha-s-triazine linkages. It is found that the experimental material obtained in 66 percent yield from the commercial fluid exhibits, over an 8 hr period at 300 C in the presence of Ti(4Al, 4Mn) alloy, thermal oxidative stability better by a factor of 2.6 x 1000 based on volatiles evolved than the commercial product. The viscosity and molecular weight of the developed fluid are unchanged and are essentially identical with the commercial material. No metal corrosion occurs with the experimental fluid at 300 C.

Jones, William R., Jr.; Paciorek, Kazimiera J. L.; Nakahara, James H.; Smythe, Mark E.; Kratzer, Reinhold H.

1987-01-01

213

Quantitative determination of glyphosate in human serum by 1H NMR spectroscopy  

Microsoft Academic Search

The determination and quantification of glyphosate in serum using 1H NMR spectroscopy is reported. This method permitted serum samples to be analysed without derivatization or any other sample pre-treatment, using 3-trimethylsilyl 2,2?,3,3?-tetradeuteropropionic acid (TSP-d4) as a qualitative and quantitative standard. Characterization of the herbicide N-(phosphonomethyl)glycine was performed by analysing chemical shifts and coupling constant patterns. Quantification was performed by relative

Bernard Cartigny; Nathalie Azaroual; Michel Imbenotte; Daniel Mathieu; Erika Parmentier; Gaston Vermeersch; Michel Lhermitte

2008-01-01

214

Serum haptoglobin in liver disease  

PubMed Central

Serum haptoglobin levels have been measured in 115 cases of widely differing liver disease. Although low levels were found in some cases of cirrhosis and a number of patients with obstructive jaundice had increased levels, 70% of the values fell within the normal range. The estimation was of no help in distinguishing between intra- and extrahepatic obstructive jaundice. A characteristic pattern was observed in infective hepatitis, and a falling serum haptoglobin in the presence of increasing jaundice is diagnostic of the latter condition. The cause of these changes is uncertain. Low levels could not be accounted for by increased red cell breakdown and there was no correlation with the serum albumin level. Prednisolone therapy produced a rise in serum haptoglobin level in cirrhosis, which was accompanied by an improvement in liver function. Temporary rises in level were observed in intrahepatic obstructive jaundice and were probably due to a non-specific effect of prednisolone. In the latter condition norethandrolone therapy was often associated with high levels. ImagesFIG. 5 PMID:14007214

Williams, Roger; Speyer, Barbara E.; Billing, Barbara H.

1961-01-01

215

Predictors of Serum Chlorinated Pesticide Concentrations among Prepubertal Russian Boys  

PubMed Central

Background: Few studies have evaluated predictors of childhood exposure to organochlorine pesticides (OCPs), a class of lipophilic persistent chemicals. Objectives: Our goal was to identify predictors of serum OCP concentrations—hexachlorobenzene (HCB), ?-hexachlorocyclohexane (?-HCH), and p,p-dichlorodiphenyldichloroethylene (p,p´-DDE)—among boys in Chapaevsk, Russia. Methods: Between 2003 and 2005, 499 boys 8–9 years of age were recruited in a prospective cohort. The initial study visit included a physical examination; blood collection; health, lifestyle, and food-frequency questionnaires; and determination of residential distance from a local factory complex that produced HCB and ?-HCH. Fasting serum samples were analyzed for OCPs at the U.S. Centers for Disease Control and Prevention. General linear regression models were used to identify predictors of the boys’ serum HCB, ?-HCH, and p,p´-DDE concentrations. Results: Among 355 boys with OCP measurements, median serum HCB, ?-HCH, and p,p´-DDE concentrations were 158, 167, and 284 ng/g lipid, respectively. Lower body mass index, longer breastfeeding duration, and local dairy consumption were associated with higher concentrations of OCPs. Boys who lived < 2 km from the factory complex had 64% (95% CI: 37, 96) and 57% (95% CI: 32, 87) higher mean HCB and ?-HCH concentrations, respectively, than boys who lived ? 5 km away. Living > 3 years in Chapaevsk predicted higher ?-HCH concentrations, and having parents who lacked a high school education predicted higher p,p´-DDE concentrations. Conclusions: Among this cohort of prepubertal Russian boys, predictors of serum OCPs included consumption of local dairy products, longer local residence, and residential proximity to the local factory complex. Citation: Lam T, Williams PL, Burns JS, Sergeyev O, Korrick SA, Lee MM, Birnbaum LS, Revich B, Altshul LM, Patterson DG Jr, Turner WE, Hauser R. 2013. Predictors of serum chlorinated pesticide concentrations among prepubertal Russian boys. Environ Health Perspect 121:1372–1377;?http://dx.doi.org/10.1289/ehp.1306480 PMID:23955839

Williams, Paige L.; Burns, Jane S.; Sergeyev, Oleg; Korrick, Susan A.; Lee, Mary M.; Birnbaum, Linda S.; Revich, Boris; Altshul, Larisa M.; Patterson, Donald G.; Turner, Wayman E.; Hauser, Russ

2013-01-01

216

Piezoelectric microcantilever serum protein detector  

NASA Astrophysics Data System (ADS)

The development of a serum protein detector will provide opportunities for better screening of at-risk cancer patients, tighter surveillance of disease recurrence and better monitoring of treatment. An integrated system that can process clinical samples for a number of different types of biomarkers would be a useful tool in the early detection of cancer. Also, screening biomarkers such as antibodies in serum would provide clinicians with information regarding the patient's response to treatment. Therefore, the goal of this study is to develop a sensor which can be used for rapid, all-electrical, real-time, label-fee, in-situ, specific quantification of cancer markers, e.g., human epidermal receptor 2 (Her2) or antibodies, in serum. To achieve this end, piezoelectric microcantilever sensors (PEMS) were constructed using an 8 mum thick lead magnesium niobate-lead titanate (PMN-PT) freestanding film as the piezoelectric layer. The desired limit of detection is on the order of pg/mL. In order to achieve this goal the higher frequency lateral extension modes were used. Also, as the driving and sensing of the PEMS is electrical, the PEMS must be insulated in a manner that allows it to function in aqueous solutions. The insulation layer must also be compatible with standardized bioconjugation techniques. Finally, detection of both cancer antigens and antibodies in serum was carried out, and the results were compared to a standard commercialized protocol. PEMS have demonstrated the capability of detecting Her2 at a concentration of 5 pg/mL in diluted human serum (1:40) in less than 1 hour. The approach can be easily translated into the clinical setting because the sensitivity is more than sufficient for monitoring prognosis of breast cancer patients. In addition to Her2 detection, antibodies in serum were assayed in order to demonstrate the feasibility of monitoring the immune response for antibody-dependent cellular cytotoxicity (ADCC) in patients on antibody therapies such as Herceptin and Cetuximab. The PEMS displayed a limit of detection of 100 fg/mL, which was 100 times lower than the current methods of protein detection in serum, such as ELISA. Furthermore, the sensitivity of the PEMS device allows it to be capable of determining the dissociation constant, K d, of selective receptors such as antibodies. Using the dose response trials of Her2, Kd has been deduced for H3 scFv, and Herceptin, a commercial antibody specific for Her2.

Capobianco, Joseph A.

217

Chemical Changes  

NSDL National Science Digital Library

In this activity you will learn what a chemical change is. The first step to understanding chemical changes is to recognize the difference between chemical properties and physical properties. Click here for an example: Chemical and Physical Changes What are the signs of a chemical reaction occuring? Signs of Chemical Change What variables affect a chemical reaction? Variables ...

Mr. Jolley

2005-10-25

218

Decline in perfluorooctane sulfonate and perfluorooctanoate serum concentrations in an Australian population from 2002 to 2011.  

PubMed

Some perfluoroalkyl and polyfluoroalkyl substances (PFASs) have become widespread pollutants detected in human and wildlife samples worldwide. The main objective of this study was to assess temporal trends of PFAS concentrations in human blood in Australia over the last decade (2002-2011), taking into consideration age and sex trends. Pooled human sera from 2002/03 (n=26); 2008/09 (n=24) and 2010/11 (n=24) from South East Queensland, Australia were obtained from de-identified surplus pathology samples and compared with samples collected previously from 2006/07 (n=84). A total of 9775 samples in 158 pools were available for an assessment of PFASs. Stratification criteria included sex and age: <16 years (2002/03 only); 0-4 (2006/07, 2008/09, 2010/11); 5-15 (2006/07, 2008/09, 2010/11); 16-30; 31-45; 46-60; and >60 years (all collection periods). Sera were analyzed using on-line solid-phase extraction coupled to high-performance liquid chromatography-isotope dilution-tandem mass spectrometry. Perfluorooctane sulfonate (PFOS) was detected in the highest concentrations ranging from 5.3-19.2 ng/ml (2008/09) to 4.4-17.4 ng/ml (2010/11). Perfluorooctanoate (PFOA) was detected in the next highest concentration ranging from 2.8-7.3 ng/ml (2008/09) to 3.1-6.5 ng/ml (2010/11). All other measured PFASs were detected at concentrations <1 ng/ml with the exception of perfluorohexane sulfonate which ranged from 1.2-5.7 ng/ml (08/09) and 1.4-5.4 ng/ml (10/11). The mean concentrations of both PFOS and PFOA in the 2010/11 period compared to 2002/03 were lower for all adult age groups by 56%. For 5-15 year olds, the decrease was 66% (PFOS) and 63% (PFOA) from 2002/03 to 2010/11. For 0-4 year olds the decrease from 2006/07 (when data were first available for this age group) was 50% (PFOS) and 22% (PFOA). This study provides strong evidence for decreasing serum PFOS and PFOA concentrations in an Australian population from 2002 through 2011. Age trends were variable and concentrations were higher in males than in females. Global use has been in decline since around 2002 and hence primary exposure levels are expected to be decreasing. Further biomonitoring will allow assessment of PFAS exposures to confirm trends in exposure as primary and eventually secondary sources are depleted. PMID:24980755

Toms, L-M L; Thompson, J; Rotander, A; Hobson, P; Calafat, A M; Kato, K; Ye, X; Broomhall, S; Harden, F; Mueller, J F

2014-10-01

219

Serum biochemical parameters of Huso huso  

Microsoft Academic Search

Serum biochemical parameters are important aspects in the management of endangered species such as Huso huso. The values of these parameters can be used for confirming the sex and any changes in the quality of waters and related soils. Serum samples of 15 H. huso fish were analysed and their serum parameter values were determined as mean±SD in both sexes.

Farzad Asadi; Ali Halajian; Malihe Pourkabir; Peyman Asadian; Farah Jadidizadeh

2006-01-01

220

Serum Dioxin Concentrations and Age at Menopause  

PubMed Central

2,3,7,8-Tetrachlorobenzo-p-dioxin (TCDD), a halogenated compound that binds the aryl hydrocarbon receptor, is a by-product of numerous industrial processes including waste incineration. Studies in rats and monkeys suggest that TCDD may affect ovarian function. We examined the relationship of TCDD and age at menopause in a population of women residing near Seveso, Italy, in 1976, at the time of a chemical plant explosion. We included 616 of the women who participated 20 years later in the Seveso Women’s Health Study. All women were premenopausal at the time of the explosion, had TCDD levels measured in serum collected soon after the explosion, and were ? 35 years of age at interview. Using proportional hazards modeling, we found a 6% nonsignificant increase in risk of early menopause with a 10-fold increase in serum TCDD. When TCDD levels were categorized, compared with women in the lowest quintile (< 20.4 ppt), women in quintile 2 (20.4–34.2 ppt) had a hazard ratio (HR) of 1.1 (p = 0.77), quintile 3 (34.3–54.1 ppt) had an HR of 1.4 (p = 0.14), quintile 4 (54.2–118 ppt) had an HR of 1.6 (p = 0.10), and quintile 5 (> 118 ppt) had an HR of 1.1 (p = 0.82) for risk of earlier menopause. The trend toward earlier menopause across the first four quintiles is statistically significant (p = 0.04). These results suggest a nonmonotonic dose-related association with increasing risk of earlier menopause up to about 100 ppt TCDD, but not above. PMID:16002373

Eskenazi, Brenda; Warner, Marcella; Marks, Amy R.; Samuels, Steven; Gerthoux, Pier ario; Vercellini, Paolo; Olive, David L.; Needham, Larry; Patterson, Donald G.; Mocarelli, Paolo

2005-01-01

221

Population based study on serum ionised calcium, serum parathyroid hormone, and blood pressure. The Tromso study  

Microsoft Academic Search

Objective: To study associations between serum ionised calcium, serum parathyroid hormone (PTH) and blood pressure. Design: A population based, cross-sectional study was used. Methods: Blood pressure, body mass index, serum ionised calcium and serum PTH were measured in 460 males and 486 females in the Tromsř study in 1994\\/1995. None were on medication for hypertension. The data were analysed with

Rolf Jorde; Kaare H Břnaa; Johan Sundsfjord

1999-01-01

222

Chemical Mechanical Planarization- Chemical  

NSDL National Science Digital Library

This website includes an animation which illustrates the chemical action of slurry in the chemical-mechanical planarization process. Objective: Explain the mechanical and chemical steps in the CMP process. This simulation is from Module 068 of the Process & Equipment III Cluster of the MATEC Module Library (MML). Find this animation under the section "Process & Equipment III." To view other clusters or for more information about the MML visit http://matec.org/ps/library3/process_I.shtmlKey Phrase: MATEC Animation

223

Chemical Threats  

MedlinePLUS

... indicate a chemical agent release. Before Before a Chemical Threat What you should do to prepare for ... and on the highest level. During During a Chemical Threat What you should do in a chemical ...

224

Chemical Emergencies  

MedlinePLUS

When a hazardous chemical has been released, it may harm people's health. Chemical releases can be unintentional, as in the case of an ... the case of a terrorist attack with a chemical weapon. Some hazardous chemicals have been developed by ...

225

Serum Survivin Increases in Prolactinoma  

PubMed Central

Background Prolactinoma is the most common adult pituitary adenoma. Survivin is a member of the family of inhibitors of apoptosis proteins. Its expression is observed in many tumors. Survivin expression has shown in prolactinoma tissue before but no study exists showing serum survivin level. The aim of the present study was to investigate serum survivin levels in patients with prolactinoma and demonstrate its value in diagnosis of the disease. Methods The group of patients consisted of 25 women, aged from 17 to 51 years. As a control group, 21 healthy women, aged from 22 to 45 years were included. Twenty patients had microprolactinoma, while five patients had macroprolactinoma. All patients had received dopamine agonist treatment. Serum survivin levels were measured in all of the groups. Results Survivin levels were significantly higher in prolactinoma patients compared to controls (19.04 (10 - 38) pg/mL; 15.05 (8 - 22) pg/mL; P = 0.042). There was no difference between microadenoma and macroadenoma patients in survivin levels (19.22 (10 - 38) pg/mL; 18.40 (16 - 22) pg/mL; P = 0.914). In correlation analysis, survivin was not correlated with other parameters. Conclusions We consider that higher survivin levels might be a molecular marker predicting the presence of prolactinoma and may be useful for the diagnosis. But large-scale research is needed to clarify its role in diagnosis of prolactinoma patients. PMID:25699121

Dellal, Fatma Dilek; Niyazoglu, Mutlu; Gorar, Suheyla; Ademoglu, Esranur; Candan, Zehra; Bekdemir, Handan; Hacioglu, Yalcin; Kaya, Fatih Oner

2015-01-01

226

Hematology and serum chemistry of the island spotted skunk on Santa Cruz Island.  

PubMed

We determined serum biochemistry and hematologic values for island spotted skunks (Spilogale gracilis amphiala) on Santa Cruz Island (California, USA). Samples were collected from island spotted skunks chemically restrained with ketamine hydrochloride and acepromazine in August 1999 (dry season) and from skunks manually restrained in August 2000 (dry season) and January 2001 (wet season). One parameter, glucose, significantly differed with season, with higher levels during the wet season. Serum chemistry and hematologic profiles suggest that method of restraint (manual or chemical), as well as other methodologic details, may influence blood characteristics in the island spotted skunk. PMID:12910779

Crooks, Kevin R; Garcelon, D K; Scott, Cheryl A; Wilcox, Jeffery T; Timm, Steven F; Van Vuren, Dirk H

2003-04-01

227

Bacteriostatic Activity of Serum Against Staphylococci  

PubMed Central

Cybulska, Janina (State Institute of Hygiene, Warsaw, Poland), and J. Jeljaszewicz. Bacteriostatic activity of serum against staphylococci. J. Bacteriol. 91:953–962. 1966.—Antistaphylococcal activity of normal serum against strains exhibiting various patterns of coagulase, clumping-factor, and staphylokinase production is not connected with the presence of these factors. Purified coagulase does not influence this property of serum. Coagulase-negative strains with clumping-factor activity grow in normal serum as typical pathogenic staphylococci. Serum bacteriostatic activity against staphylococci may be reversed by several nonspecific factors, such as sterile broth, supernatant fluids of coagulase-negative strains, and ammonium sulfate precipitates of culture supernatant fluids of various staphylococci. Immune sera with a high agglutinating titer for staphylococcal cells do not prevent growth of serum-resistant strains; serum-susceptible strains are inhibited as in normal serum control. Activation or blocking of the serum fibrinolytic system does not influence serum bacteriostatic activity. The growth rate of serum-resistant strains is identical in serum and in Todd-Hewitt broth; serum-susceptible strains are inhibited to the inoculum level, but decreases and increases in viable count are noted during a 24-hr observation period. Observations made with sera of 10 animal species clearly demonstrated differences in serum bacteriostatic activity, mouse serum being completely noninhibitory and cat serum only weakly inhibitory. The technique of quantitative determination of serum susceptibility of staphylococci is described, and the importance of serum antistaphylococcal activity in vitro is discussed. Experimental staphylococcal infection produced in rabbits by intravenous injection of different Staphylococcus aureus strains did not result in significant changes in serum antistaphylococcal activity. The technique of experimental infection used caused chronic infection, with a peak on the 14th day; this was proved by means of a newly developed 5?-nucleotidase test. At the same time, sera of infected animals exhibited slight inhibitory properties, which returned to initial values 1 week later. Infection was produced by strains recognized as nonpathogenic and was inhibited in vitro by sera from both normal and infected rabbits. It is concluded that antistaphylococcal activity of serum should be considered as an “in vitro” phenomenon, which seems to have no importance in defense mechanisms of rabbits infected intravenously with staphylococci. PMID:5929770

Cybulska, Janina; Jeljaszewicz, J.

1966-01-01

228

Host and environmental determinants of polychlorinated aromatic hydrocarbons in serum of adolescents.  

PubMed Central

This study investigated host factors and environmental factors as potential determinants of polychlorinated aromatic hydrocarbons (PCAHs) in serum of adolescents. We recruited 200 participants (80 boys and 120 girls), with a mean age of 17.4 years (SD, 0.8), in Belgium from a rural control area (Peer) and from two polluted suburbs of Antwerp where a nonferrous smelter (Hoboken) and waste incinerators (Wilrijk) are located. We quantified polychlorinated biphenyls (PCBs; congeners 138, 153, and 180) in serum by gas chromatography and obtained the toxic equivalents (TEQs) of PCAHs in serum with the chemically activated luciferase gene expression bioassay (CALUX). Serum PCB concentration was higher in boys than in girls (1.67 vs. 1.02 nmol/L or 377 vs. 210 pmol/g serum lipids; p< 0.001). In the whole adolescent group, multiple regression showed that serum PCB concentration decreased 0.06 nmol/L per 1% increase in body fat content (p< 0.001) and increased 0.39 nmol/L and 0.14 nmol/L per 1 mmol/L increase in serum concentrations of triglycerides (p < 0.001) and cholesterol (p = 0.002), respectively. Host factors explained 44% of the serum PCB variance. In the same model, serum PCB concentration increased 0.14 nmol/L with 10 weeks of breast-feeding (p< 0.001) and 0.06 nmol/L with intake of 10 g animal fat per day (p < 0.001), and was associated with residence in the waste incinerator area (9% higher; p = 0.04); 11% of the variance could be explained by these environmental factors. The geometric mean of the serum TEQ value was similar in boys and girls (0.15 TEQ ng/L or 33.0 pg/g serum lipids). In multiple regression, TEQ in serum decreased 0.03 ng/L per centimeter increase in triceps skinfold (p = 0.006) and was 29% higher in subjects living close to the nonferrous smelter (p < 0.001). This study showed that in 16- to 18-year-old teenagers host factors are important determinants of serum concentrations of PCAHs, whereas environmentally related determinants may to some extent contribute independently to human exposure to these persistent chemicals in the environment. PMID:12055049

Nawrot, Tim S; Staessen, Jan A; Den Hond, Elly M; Koppen, Gudrun; Schoeters, Greet; Fagard, Robert; Thijs, Lutgarde; Winneke, Gerhard; Roels, Harry A

2002-01-01

229

Reduction of blood serum cholesterol  

NASA Technical Reports Server (NTRS)

By feeding a human subject as the sole source of sustenance a defined diet wherein the carbohydrate consists substantially entirely of glucose, maltose or a polysaccharide of glucose, the blood serum cholesterol level of the human subject is substantially reduced. If 25 percent of the carbohydrate is subsequently supplied in the form of sucrose, an immediate increase from the reduced level is observed. The remainder of the defined diet normally includes a source of amino acids, such as protein or a protein hydrolysate, vitamins, minerals and a source of essential fatty acid.

Winitz, M. (inventor)

1974-01-01

230

Chemical milling  

Microsoft Academic Search

Chemical milling was used in removing excess material and reducing overall weight of metal parts. Chemical milling is discussed generally, describing the process, its applications, advantages and limitations, chemical milling solutions, maskants, and various other aspects of the chemical milling process. The effectiveness of chemical milling of specific materials such as aluminum, beryllium, magnesium, titanium, steel, and stainless steel alloys

J. W. Dini

1974-01-01

231

Oxidative folding of hirudin in human serum  

PubMed Central

Human serum contains factors that promote oxidative folding of disulphide proteins. We demonstrate this here using hirudin as a model. Hirudin is a leech-derived thrombin-specific inhibitor containing 65 amino acids and three disulphide bonds. Oxidative folding of hirudin in human serum is shown to involve an initial phase of rapid disulphide formation (oxidation) to form the scrambled isomers as intermediates. This is followed by the stage of slow disulphide shuffling of scrambled isomers to attain the native hirudin. The kinetics of regenerating the native hirudin depend on the concentrations of both hirudin and human serum. Quantitative regeneration of native hirudin in undiluted human serum can be completed within 48 h, without any redox supplement. These results cannot be adequately explained by the existing oxidized thiol agents in human serum or the macromolecular crowding effect, and therefore indicate that human serum may contain yet to be identified potent oxidase(s) for assisting protein folding. PMID:16271042

Chang, Jui-Yoa; Lu, Bao-Yun; Lai, Por-Hsiung

2005-01-01

232

?1,4Fucosyltransferase Activity in Human Serum and Saliva  

Microsoft Academic Search

A novel bioluminescence-based solid-phase assay is described for the enzyme GDPFuc:Gal?1–3GlcNAc (Fuc to GlcNAc) ?1,4-fucosyltransferase (?1,4FT), which generates the Lewis a blood group antigen (Lea) (Gal?1–3[Fuc?1–4]GlcNAc–R). Lacto-N-tetraose (LNT, Gal?1–3GlcNAc?1–3Gal?1–4Glc) was chemically conjugated to bovine serum albumin (BSA) to generate the acceptor neoglycoprotein LNT–BSA. The Leaproduct of the reaction made in the presence of the donor GDPFuc is detected with a

Russell A. Debose-Boyd; A. Kwame Nyame; David F. Smith; Richard D. Cummings

1996-01-01

233

Studies on ceruloplasmin of bovine serum  

E-print Network

and the increase in cX-globulins may be due to an augmentation of ceruloplasmin in the serum following thermal injuries. The work of Markowitz (15) verified the high correlations among total serum copper, indirect-reacting copper, ceruloplasmin and oxidase....284 Serum albumin 24 -0.609** Hemoglobin 12 -0.355 Total white blood cells 24 -0.182 ** Probability of chance occurrence less than 0.01. 33 of Markowitz e? 4569 (15) in which a...

Deyoe, Charles Walter

1959-01-01

234

Potyclonal GammopathywithMarkedIncreasein Serum Viscosity  

Microsoft Academic Search

A 45-year-oldmanwithpolyclonal hypergammaglobuline- mia (gamma globulins,102 g\\/L) had a serum relative viscosity of 13 v but did not manifestclinicalsigns of hyperviscosftysyndrome(e.g., retinopathy, bleedingdia- thesis, and neurological alterations), except for fatigue and anorexia.In contrastwithotherpatientswithpolyclo- nalhyperviscosityreported so far, thispatientdidnothave detectable rheumatoid factor in serum. Analytical ultra- centrifugatlon of his serumshowedaggregatesof poly- clonallgG3of varioussizes (between 10 and 36 S). The serum also contained

Barbara M. Roach; Shirin M. Farahmand

235

[Placenta antigens in serum of pregnant women].  

PubMed

Antiplacenta serum was produced in rabbits using placenta extract; 3 different placenta antigens were demonstrated in placenta extract by means of the rabbit serum. These placenta antigens were found in the serum of pregnant women with normal and pathological pregnancies,in the urine of pregnant women, in the amniotic fluid, umbilical cord blood, and in the ascites of dropsical infants. The immunological characterization of the placental antigens is described in detail. PMID:5171383

Schultze-Mosgau, H; Fischer, K

1971-10-28

236

Chemical Equations  

NSDL National Science Digital Library

It discusses the process of equation writing and balancing chemical equations in perspective of the chemical changes that take place during a reaction. This module is the third in a series on chemical reactions.

Anthony Carpi

2003-03-27

237

Serum Dihydrolipoamide Dehydrogenase Is a Labile Enzyme  

PubMed Central

Dihydrolipoamide dehydrogenase (DLDH) is a multifunctional oxidoreductase and is well known as an essential component of four mammalian mitochondrial multienzyme complexes: pyruvate dehydrogenase, ?-ketoglutarate dehydrogenase, branched chain ?-keto acid dehydrogenase, and the glycine cleavage system. However, existence of extracellular DLDH in mammals, if any, has not been clearly defined. The present article reports identification and biochemical characterization of serum DLDH. Proteomic analysis of rat serum using blue native polyacrylamide gel electrophoresis (BN-PAGE) and mass spectrometry peptide sequencing led to generation of 6 tryptic peptides in one band that matched to mitochondrial DLDH, indicating the existence of DLDH in rat serum. Measurement of enzymatic activity also indicated the existence of DLDH in human and mouse serum. Further biochemical analysis of rat serum DLDH revealed that this enzyme lacked diaphorase activity and could not be detected on Western blots probed with antibodies that recognized mitochondrial DLDH. Moreover, both ammonium sulfate fractioning and gel filtration of serum samples rendered a great loss in DLDH activity, indicating that the enzyme activity of this serum protein, unlike that of mitochondrial DLDH, is very labile. When DTT was supplemented in the buffer used for gel filtration, DLDH activity was found to be largely preserved; indicating that serum DLDH is susceptible to air-implicated inactivation. Results of the present study indicate that serum DLDH differs from mitochondrial DLDH in that it is a very labile enzyme. PMID:23646291

Yan, Liang-Jun; Thangthaeng, Nopporn; Sumien, Nathalie; Forster, Michael J.

2013-01-01

238

Hematology and Serum Chemistry of the Island Spotted Skunk on Santa Cruz Island  

Microsoft Academic Search

We determined serum biochemis- try and hematologic values for island spotted skunks (Spilogale gracilis amphiala) on Santa Cruz Island (California, USA). Samples were collected from island spotted skunks chemically restrained with ketamine hydrochloride and acepromazine in August 1999 (dry season) and from skunks manually restrained in August 2000 (dry season) and January 2001 (wet sea- son). One parameter, glucose, significantly

Kevin R. Crooks; D. K. Garcelon; Cheryl A. Scott; Jeffery T. Wilcox; Steven F. Timm; Dirk H. Van

2003-01-01

239

Decreased levels of CXC-chemokines in serum of benzene-exposed workers identified by  

E-print Network

Decreased levels of CXC-chemokines in serum of benzene-exposed workers identified by array (received for review October 3, 2004) Benzene is an important industrial chemical and environmental contaminant that causes leukemia. To obtain mechanistic insight into benzene's mechanism of action, we

California at Berkeley, University of

240

VX Hydrolysis by Human Serum Paraoxonase 1: A Comparison of Experimental and Computational Results  

E-print Network

Human Serum paraoxonase 1 (HuPON1) is an enzyme that has been shown to hydrolyze a variety of chemicals including the nerve agent VX. While wildtype HuPON1 does not exhibit sufficient activity against VX to be used as an ...

Peterson, Matthew W.

241

A COMPARISON BETWEEN CONVALESCENT SERUM AND NON-CONVALESCENT SERUM IN POLIOMYELITIS  

PubMed Central

1. Of twenty-nine so called normal urban adults tested, seven had less than two-fifths, three had two-fifths, two had three-fifths, eight had four-fifths and nine had a neutralizing power at least equal to the average of five batches of pooled convalescent serum. 2. Known contacts and avowed non-contacts were equally represented in the serums of low potency, but in the serums of higher potency, the known contacts predominated. 3. The pooled serums of known contacts and of non-contacts were respectively a little above and a little below half the strength of the average obtained for pooled convalescent serum. 4. Two series of early cases of poliomyelitis, the one treated with normal serum of proved protective power, the other with convalescent serum, showed no advantage of one type of serum over the other. PMID:19870082

Brodie, Maurice

1932-01-01

242

Optimizing Cationic and Neutral Lipids for Efficient Gene Delivery at High Serum Content  

PubMed Central

Background Cationic liposome (CL)-DNA complexes are promising gene delivery vectors with potential applications in gene therapy. A key challenge in creating CL-DNA complexes for applications is that their transfection efficiency (TE) is adversely affected by serum. In particular, little is known about the effects of high serum contents on TE even though this may provide design guidelines for applications in vivo. Methods We prepared CL-DNA complexes in which we varied the neutral lipid (DOPC, glycerol-monooleate (GMO), cholesterol), the headgroup charge and chemical structure of the cationic lipid, and the ratio of neutral to cationic lipid; we then measured the TE of these complexes as a function of serum content and assessed their cytotoxicity. We tested selected formulations in two human cancer cell lines (M21/melanoma and PC-3/prostate cancer). Results In the absence of serum, all CL-DNA complexes of custom-synthesized multivalent lipids show high TE. Certain combinations of multivalent lipids and neutral lipids, such as MVL5(5+)/GMO-DNA complexes or complexes based on the dendritic-headgroup lipid TMVLG3(8+) exhibited high TE both in the absence and presence of serum. Although their TE still dropped to a small extent in the presence of serum, it reached or surpassed that of benchmark commercial transfection reagents, in particular at high serum content. Conclusions Two-component vectors (one multivalent cationic lipid and one neutral lipid) can rival or surpass benchmark reagents at low and high serum contents (up to 50%, v/v). We suggest guidelines for optimizing the serum resistance of CL-DNA complexes based on a given cationic lipid. PMID:24753287

Majzoub, Ramsey N.; Hwu, Yeu-kuang; Liang, Keng S.; Leal, Cecília; Safinya, Cyrus R.

2014-01-01

243

Production of recombinant protein C in serum-containing and serum-free perfusion culture  

Microsoft Academic Search

For the development of a perfusion culture producing recombinant human protein C, the effects of fetal calf serum and growth factors on cell growth and recombinant protein production were investigated. Although the growth of recombinant cells was stimulated by serum in a dose-dependent manner, a lower concentration of serum (2%) could support both synthesis and post-translational modification of protein C

Takeyuki Sugiura; Hiromi B. Maruyama

1991-01-01

244

Antibacterial properties of serum from the American alligator ( Alligator mississippiensis)  

Microsoft Academic Search

Treatment of alligator (Alligator mississippiensis) and human serum samples with Escherichia coli resulted in a time- and concentration-dependent inhibition of bacterial proliferation. When inoculated with E. coli, alligator serum exhibited 10-fold lower bacterial survival rates after 1 h than human serum. In addition, the antibacterial spectrum of alligator serum was shown to be much broader than that of human serum,

Mark E. Merchant; Cherie Roche; Ruth M. Elsey; Jan Prudhomme

2003-01-01

245

Distribution of air and serum PCDD\\/F levels of electric arc furnaces and secondary aluminum and copper smelters  

Microsoft Academic Search

Metallurgical processes, such as smelting, can generate organic impurities such as organic chloride chemicals, polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD\\/Fs). The objective of this study was to elucidate the serum PCDD\\/F levels of 134 workers and ambient air levels around electric arc furnaces (EAF), secondary copper smelters and secondary aluminum smelters (ALSs) in Taiwan. The highest serum PCDD\\/F levels were

Ching-Chang Lee; Tung-Seng Shih; Hsiu-Ling Chen

2009-01-01

246

Serum lipid levels, suicidality, and panic disorder  

Microsoft Academic Search

Although the effects of serum total cholesterol and other lipids have been implicated as a predictor of suicidal behavior in major depression, the role of cholesterol level on suicide risk for panic disorder patients is not considered as a biological marker in the literature. In this study, we examined the relationship of suicidality with serum cholesterol concentration in panic disorder.

Ömer Akil Özer; Remzi Kutani?; Mehmet Yücel Agargun; Ahmet Cemal Bal; Yavuz Selvi; Hayrettin Kara

2004-01-01

247

Serum lipid levels in Sjogren's syndrome  

Microsoft Academic Search

Objectives. Altered lipid levels may occur in autoimmune diseases, for example low cholesterol levels have been described in rheumatoid arthritis (RA). Serum lipid profiles in patients with Sjogren's syndrome (SS) have not been investigated. We hypothesized decreased lipid levels in SS patients and an inverse relationship with disease activity. Methods. Serum lipid levels [total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein

B. M. Lodde; V. Sankar; M. R. Kok; R. A. Leakan; P. P. Tak; S. R. Pillemer

2006-01-01

248

Serum lipid levels in Sjogren's syndrome  

Microsoft Academic Search

Objectives. Altered lipid levels may occur in autoimmune diseases, for example low cholesterol levels have been described in rheumatoid arthritis (RA). Serum lipid profiles in patients with Sjogren's syndrome (SS) have not been investigated. We hypothesized decreased lipid levels in SS patients and an inverse relationship with disease activity. Methods. Serum lipid levels (total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein

B. M. Lodde; V. Sankar; M. R. Kok; R. A. Leakan; P. P. Tak; S. R. Pillemer

2005-01-01

249

Serum Protein Profile Alterations in Hemodialysis Patients  

SciTech Connect

Background: Serum protein profiling patterns can reflect the pathological state of a patient and therefore may be useful for clinical diagnostics. Here, we present results from a pilot study of proteomic expression patterns in hemodialysis patients designed to evaluate the range of serum proteomic alterations in this population. Methods: Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOFMS) was used to analyze serum obtained from patients on periodic hemodialysis treatment and healthy controls. Serum samples from patients and controls were first fractionated into six eluants on a strong anion exchange column, followed by application to four array chemistries representing cation exchange, anion exchange, metal affinity and hydrophobic surfaces. A total of 144 SELDI-TOF-MS spectra were obtained from each serum sample. Results: The overall profiles of the patient and control samples were consistent and reproducible. However, 30 well-defined protein differences were observed; 15 proteins were elevated and 15 were decreased in patients compared to controls. Serum from one patient exhibited novel protein peaks suggesting possible additional changes due to a secondary disease process. Conclusion: SELDI-TOF-MS demonstrated dramatic serum protein profile differences between patients and controls. Similarity in protein profiles among dialysis patients suggests that patient physiological responses to end-stage renal disease and/or dialysis therapy have a major effect on serum protein profiles.

Murphy, G A; Davies, R W; Choi, M W; Perkins, J; Turteltaub, K W; McCutchen-Maloney, S L; Langlois, R G; Curzi, M P; Trebes, J E; Fitch, J P; Dalmasso, E A; Colston, B W; Ying, Y; Chromy, B A

2003-11-18

250

Antibodies to Polynucleotides: Distribution in Human Serums  

Microsoft Academic Search

Hemagglutination procedures were used to determine the distribution of antibodies to native DNA, single-stranded DNA, and double-stranded RNA. Antibodies to all three polynucleotides were found in a high percentage of the serums of patients with systemic lupus erythematosus. Antibodies to native DNA occurred almost exclusively in serums of patients in the active stages of systemic lupus erythematosus, whereas antibodies to

D. Koffler; R. I. Carr; V. Agnello; T. Fiezi; H. G. Kunkel

1969-01-01

251

Serum Ferritin: Past, Present and Future  

PubMed Central

Background Serum ferritin was discovered in the 1930’s, and was developed as a clinical test in the 1970’s. Many diseases are associated with iron overload or iron deficiency. Serum ferritin is widely used in diagnosing and monitoring these diseases. Scope of Review In this chapter, we discuss the role of serum ferritin in physiological and pathological processes and its use as a clinical tool. Major Conclusions Although many aspects of the fundamental biology of serum ferritin remain surprisingly unclear, a growing number of roles have been attributed to extracellular ferritin, including newly described roles in iron delivery, angiogenesis, inflammation, immunity, signaling and cancer. General Significance Serum ferritin remains a clinically useful tool. Further studies on the biology of this protein may provide new biological insights. PMID:20304033

Wang, Wei; Knovich, Mary Ann; Coffman, Lan G.; Torti, Frank M.; Torti, Suzy V.

2010-01-01

252

Production of recombinant protein C in serum-containing and serum-free perfusion culture.  

PubMed

For the development of a perfusion culture producing recombinant human protein C, the effects of fetal calf serum and growth factors on cell growth and recombinant protein production were investigated. Although the growth of recombinant cells was stimulated by serum in a dose-dependent manner, a lower concentration of serum (2%) could support both synthesis and post-translational modification of protein C as efficiently as 10% serum. Among the growth factors tested, transferrin enhanced protein C production to the level comparable with 10% serum, while insulin was effective in maintaining cellular metabolism. Based on these results, a perfusion culture for a scale-up production of recombinant protein C was done using an Opticell culture system. A good productivity of the recombinant protein was obtained in low serum or serum-free medium for more than one month. PMID:1368118

Sugiura, T; Maruyama, H B

1991-11-01

253

Human serum albumin, systemic inflammation, and cirrhosis.  

PubMed

Human serum albumin (HSA) is one of the most frequent treatments in patients with decompensated cirrhosis. Prevention of paracentesis-induced circulatory dysfunction, prevention of type-1 HRS associated with bacterial infections, and treatment of type-1 hepatorenal syndrome are the main indications. In these indications treatment with HSA is associated with improvement in survival. Albumin is a stable and very flexible molecule with a heart shape, 585 residues, and three domains of similar size, each one containing two sub-domains. Many of the physiological functions of HSA rely on its ability to bind an extremely wide range of endogenous and exogenous ligands, to increase their solubility in plasma, to transport them to specific tissues and organs, or to dispose of them when they are toxic. The chemical structure of albumin can be altered by some specific processes (oxidation, glycation) leading to rapid clearance and catabolism. An outstanding feature of HSA is its capacity to bind lipopolysaccharide and other bacterial products (lipoteichoic acid and peptidoglycan), reactive oxygen species, nitric oxide and other nitrogen reactive species, and prostaglandins. Binding to NO and prostaglandins are reversible, so they can be transferred to other molecules at different sites from their synthesis. Through these functions, HSA modulates the inflammatory reaction. Decompensated cirrhosis is a disease associated systemic inflammation, which plays an important role in the pathogenesis of organ or system dysfunction/failure. Although, the beneficial effects of HAS have been traditionally attributed to plasma volume expansion, they could also relate to its effects modulating systemic and organ inflammation. PMID:24751830

Arroyo, Vicente; García-Martinez, Rita; Salvatella, Xavier

2014-08-01

254

Assessment of infant exposure to food chemicals: the French Total Diet Study design.  

PubMed

As part of the previous French Total Diet Studies (TDS) focusing on exposure to food chemicals in the population aged 3 years and older, the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) launched a specific TDS on infants to complete its overall chemical food safety programme for the general population. More than 500 chemical substances were analysed in food products consumed by children under 3 years old, including nutrients, several endocrine disruptors resulting from human activities (polychlorinated biphenyls, dioxins and furans, brominated flame retardants, perfluoroalkyl acids, pesticide residues, etc.) or migrating from food contact materials such as bisphenol A or phthalates, but also natural substances such as mycotoxins, phytoestrogens and steroids. To obtain a representative and general view of infant food consumption, food items were selected based on results of a national consumption survey conducted specifically on this population. Moreover, a specific study on food was conducted on 429 households to determine which home-cooking practices are employed to prepare food consumed by infants. Overall, the targeted chemical substances were analysed in more than 450 food samples, representing the purchase and home-cooking practices of over 5500 food products. Foods included common foods such as vegetables, fruit or cakes as well as specific infant foods such as infant formula or jarred baby food. The sampling plan covered over 80% of the total diet. Specificities in infant food consumption and habits were therefore considered to define this first infant TDS. This study, conducted on a large scale and focusing on a particularly sensitive population, will provide accurate information on the dietary exposure of children under 3 years to food chemicals, especially endocrine disruptors, and will be particularly useful for risk assessment analysis under the remit of ANSES' expert committees. PMID:24827474

Hulin, M; Bemrah, N; Nougadčre, A; Volatier, J L; Sirot, V; Leblanc, J C

2014-01-01

255

Vitellogenin induction and reduced serum testosterone concentrations in feral male carp (Cyprinus carpio) captured near a major metropolitan sewage treatment plant.  

PubMed Central

Endocrine disrupting chemicals can potentially alter the reproductive physiology of fishes. To test this hypothesis, serum was collected from common carp (Cyprinus carpio) at five riverine locations in Minnesota. Male fish collected from an effluent channel below the St. Paul metropolitan sewage treatment plant had significantly elevated serum egg protein (vitellogenin) concentrations and significantly decreased serum testosterone concentrations compared to male carp collected from the St. Croix River, classified as a National Wild and Scenic River. Carp collected from the Minnesota River, which receives significant agricultural runoff, also exhibited depressed serum testosterone concentrations, but no serum vitellogenin was apparent. These data suggest that North American rivers are receiving estrogenic chemicals that are biologically active, as has been reported in Great Britain. Images Figure 1. Figure 2. A Figure 2. B PMID:8930552

Folmar, L C; Denslow, N D; Rao, V; Chow, M; Crain, D A; Enblom, J; Marcino, J; Guillette, L J

1996-01-01

256

Serum PBDEs in a North Carolina Toddler Cohort: Associations with Handwipes, House Dust, and Socioeconomic Variables  

PubMed Central

Background: Polybrominated diphenyl ethers (PBDEs) are persistent, bioaccumulative, and endocrine-disrupting chemicals. Objectives: We used handwipes to estimate exposure to PBDEs in house dust among toddlers and examined sex, age, breast-feeding, race, and parents’ education as predictors of serum PBDEs. Methods: Eighty-three children from 12 to 36 months of age were enrolled in North Carolina between May 2009 and November 2010. Blood, handwipe, and house dust samples were collected and analyzed for PBDEs. A questionnaire was administered to collect demographic data. Results: PBDEs were detected in all serum samples (geometric mean for ?pentaBDE in serum was 43.3 ng/g lipid), 98% of the handwipe samples, and 100% of the dust samples. Serum ?pentaBDEs were significantly correlated with both handwipe and house dust ?pentaBDE levels, but were more strongly associated with handwipe levels (r = 0.57; p < 0.001 vs. r = 0.35; p < 0.01). Multivariate model estimates revealed that handwipe levels, child’s sex, child’s age, and father’s education accounted for 39% of the variation in serum ?BDE3 levels (sum of BDEs 47, 99, and 100). In contrast, age, handwipe levels, and breast-feeding duration explained 39% of the variation in serum BDE 153. Conclusions: Our study suggests that hand-to-mouth activity may be a significant source of exposure to PBDEs. Furthermore, age, socioeconomic status, and breast-feeding were significant predictors of exposure, but associations varied by congener. Specifically, serum ?BDE3 was inversely associated with socioeconomic status, whereas serum BDE-153 was positively associated with duration of breast-feeding and mother’s education. PMID:22763040

Eagle, Sarah; Sjödin, Andreas; Webster, Thomas F.

2012-01-01

257

Killing of Brucella abortus by bovine serum.  

PubMed Central

Studies of the serum bactericidal system in bovine brucellosis were undertaken to investigate the role of the humoral immune response in protection of cattle against the facultative intracellular parasite Brucella abortus. Fresh sera from normal control cattle, infected cattle, and cattle immunized with B. abortus cell envelopes were collected before treatment and during the course of immunization or infection. Normal fresh bovine serum or fresh agammaglobulinemic serum from colostrum-deprived calves was effective in killing smooth virulent B. abortus 2308, but rough strains RB51 (a rough mutant of strain 2308) and 45/20 were much more sensitive to serum. The difference in susceptibility to serum was shown to be correlated with differences in lipopolysaccharide chemotype, with the more resistant strain 2308 having O polysaccharide and the more susceptible strains 45/20 and RB51 lacking O side chains. By treatment of fresh serum with MgCl2 and EGTA [ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid] killing was shown to occur via the classical pathway of complement activation. When antibody to B. abortus was present, killing of strain RB51 increased but killing of smooth strain 2308 decreased. The earliest antibody response in serum from infected animals did not interfere with killing. When affinity-purified bovine immunoglobulins specific for B. abortus smooth lipopolysaccharide were added to fresh normal bovine serum, immunoglobulin G1 (IgG1) and IgG2 isotypes blocked killing but IgM and IgA isotypes did not. Thus, it appears that serum from previously unexposed animals or animals early during infection can kill smooth B. abortus, an appropriate defense mechanism before the organism becomes intracellular. At later stages of infection, blocking antibodies predominate. Images PMID:3141287

Corbeil, L B; Blau, K; Inzana, T J; Nielsen, K H; Jacobson, R H; Corbeil, R R; Winter, A J

1988-01-01

258

Chemical Communication  

NSDL National Science Digital Library

A concise lesson about chemical communication in insects covering both semio and info chemicals. The site includes a short video of grape root borer moths using sex pheromone. Further links on the take the user to visual and auditory communication.

0000-00-00

259

Chemical Oxidation  

Microsoft Academic Search

Chemical oxidation is a process involving the transfer of electrons from an oxidizing reagent to the chemical species being\\u000a oxidized. In water and wastewater engineering, chemical oxidation serves the purpose of converting putrescible pollutant substances\\u000a to innocuous or stabilized products. Chemical oxidation processes take place in natural waters and serve as an important mechanism\\u000a in the natural self-purification of surface

Nazih K. Shammas; John Y. Yang; Pao-Chiang Yuan; Yung-Tse Hung

260

Home Chemicals  

NSDL National Science Digital Library

This lesson provides an introduction to the occurrence and possible risks of household chemical products. Topics include some basic chemistry (how elements combine to form compounds), how chemicals are classified, and the idea of natural, as opposed to synthetic, chemicals. The lesson includes an activity in which students take an inventory of chemical products in their homes and research the possible hazards of some of them using an online resource developed by the National Institutes of Health (NIH).

Chris Fox

261

Chemical Innovation  

NSDL National Science Digital Library

Free online through December 2000, Chemical Innovation is a monthly journal that explores topics in research and development in chemical industries, and features such departments as Patent Watch, Chemist at Large, Book Alert, and The Industrial Chemist. The journal also shows a lighter side by including chemistry-related cartoons and jokes. The online version is provided by the American Chemical Society.

262

Serum acute phase reactants in necrotizing enterocolitis.  

PubMed

The serum acute phase reactants, C-reactive protein (CRP) and orosomucoid, rose significantly within 24 to 48 hours of presentation in infants with definite necrotizing enterocolitis (NEC) compared with the levels in infants with symptoms who tolerated early reintroduction of enteral feeds. A serum CRP value greater than 10 mg/l within 48 hours identified infants with definite NEC with a 92% sensitivity and an 81% specificity. Serum CRP values remained elevated at 7 to 10 days in 4 infants with late septicaemia and in 4 of 5 infants with abscess or early stricture requiring surgery. Serum acute phase reactants are a potentially valuable adjunct to clinical assessment in the management of infants with suspected NEC. PMID:2447744

Isaacs, D; North, J; Lindsell, D; Wilkinson, A R

1987-11-01

263

Serum lipid levels in seasonal affective disorder  

Microsoft Academic Search

Previous research has assessed the relationship between blood lipid levels and depression with contradictory results. Several\\u000a studies have linked low cholesterol levels with impulsive, aggressive and suicidal behaviours. The aim of this pilot study\\u000a was to examine serum lipids in a sample of patients suffering from seasonal affective disorder (SAD). We conducted a retrospective\\u000a analysis of data on total serum

Edda Pjrek; Dietmar Winkler; David W. Abramson; Anastasios Konstantinidis; Jürgen Stastny; Matthäus Willeit; Nicole Praschak-Rieder; Siegfried Kasper

2007-01-01

264

Precision and accuracy of serum ferritin measurements.  

PubMed

For the epidemiological evaluation of iron stores the precision of serum ferritin measurement in the low range are important for the accurate determination of the prevalence of iron deficiency and the detection of subtle changes in serum ferritin levels after food iron manipulation. In addition the recognition of iron overload and the evaluation of its severity are important. In this study samples with low serum ferritin values were repetitively measured in a classic radioimmunoassay (RIA) and in two "2-site" immunoradiometric assays (IRMA), one of which used a polystyrene bead and the other a polystyrene tube fas the solid phase. Variability was significantly less with the IRMA using a bead than that using a tube. Optimum precision was noted when samples were run at the lowest possible dilution (1:10) with relatively long reaction times. The bead IRMA was also more precise that the RIA which had a standard curve with 50% radioactive binding (maximum precision) of 40 ng/ml. Within the normal serum ferritin range (12 to 300 ng/ml) extremely similar results were obtained with an RIA and IRMA. However, when iron overload samples (serum ferritin values greater than 2000 ng/ml) were examined the RIA gave values significantly lower than those obtained by IRMA. The lower values by RIA may be related to the immunological heterogeneity of serum ferritin which is maximized by an assay performed in antigen excess (RIA) and minimized by one performed in antibody excess (IRMA). These observations indicate a need for the development of specific serum ferritin assays for epidemiological studies. By manipulating the components of the standard curve the RIA and IRMA can be optimized to provide maximum precision when low serum ferritin values are being measured. in choosing an assay the ability of the method to determine the severity of iron overload must also be taken into consideration. PMID:7234722

Lipschitz, D A; Skikne, B A; Thompson, C

1981-05-01

265

Refractory intraoperative hypotension with elevated serum tryptase  

PubMed Central

Severe intraoperative hypotension has been reported in patients on angiotensin-converting enzyme inhibitors and angiotensin II receptor subtype 1 antagonists. We describe a patient on lisinopril who developed refractory intraoperative hypotension associated with increased serum tryptase level suggesting mast cell activation (allergic reaction). However, allergology workup ruled out an allergic etiology as well as mastocytosis, and hypotension recalcitrant to treatment was attributed to uninterrupted lisinopril therapy. Elevated serum tryptase was attributed to our patient's chronic renal insufficiency. PMID:25653920

Larson, Kelly J.; Divekar, Rohit D.; Butterfield, Joseph H.; Schwartz, Lawrence B.; Weingarten, Toby N.

2015-01-01

266

Brief Communication: Associations of Serum TRAIL Concentrations, Anthropometric Variables, and Serum Lipid Parameters in Healthy Adults  

Microsoft Academic Search

To investigate the relationships of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), anthropometric variables, and lipid parameters, we measured serum TRAIL concentrations, body mass index (BMI), total body fat (TBF), and serum lipid profiles in 207 healthy adults. There were no significant differences in serum TRAIL concentrations between men and women, nor between elderly persons and middle-aged subjects. However, men

Jong Weon Choi; Jung Soo Song; Soo Hwan Pai

2004-01-01

267

Micromethod for the Rapid Determination of Serum Protein-Bound Iodine and Total Serum Iodine  

Microsoft Academic Search

A modification is presentedof the chloric acid method for the rapid determination of serum protein-bound iodine and total serum iodine requiring less than 0.5 ml. serum for duplicate determinations. The time required for the entire procedure is lessthan two hours. Byadjusting the amountsof reagents used and by varying the time of digestion, the need for constant and continuoussupervisionis eliminated. 'IE1HEDETERMINATION

Eli Gardiner; Arthur Bums

268

Determination of scopolamine in human serum by gas chromatography-ion trap tandem mass spectrometry.  

PubMed

The objective of this study was to develop a very sensitive and selective method for the determination of scopolamine in serum with a rapid and simple sample preparation. A capillary column gas chromatographic-ion trap tandem mass spectrometric technique has been applied. Scopolamine and the internal standard mexiletine were extracted from serum samples and cleaned up by using a single step liquid-liquid extraction. Derivatization was carried out using 2,2,2-trifluoro-N-methyl-N-trimethylsilylacetamide. The mass spectrometer was operated with positive ions in the selected reaction mode with chemical ionisation using methane. The sum of peak height of two daughter ions was used for quantification. The detection limit was 50 pg/ml in serum. PMID:8844418

Oertel, R; Richter, K; Ebert, U; Kirch, W

1996-07-12

269

The Effects of Perfluorinated Chemicals on Adipoctye Differentiation In Vitro  

EPA Science Inventory

The 3T3-L1 preadipocyte culture system has been used to examine numerous compounds that influence adipocyte differentiation or function. The perfluoroalkyl acids (PFAAs), used as surfactants in a variety of industrial applications, are of concern as environmental contaminants tha...

270

Chemical burns  

PubMed Central

Objectives To report a burn unit’s experience with chemical burns and to discuss the fundamental principles in managing chemical burns. Design A chart review. Setting A burn centre at a major university-affiliated hospital. Patients Twenty-four patients with chemical burns, representing 2.6% of all burn admissions over an 8-year period at the Ross Tilley Regional Adult Burn Centre. Seventy-five percent of the burn injuries were work-related accidents. Chemicals involved included hydrofluoric acid, sulfuric acid, black liquor, various lyes, potassium permanganate and phenol. Results Fourteen patients required excision and skin grafting. Complications were frequent and included ocular chemical contacts, wound infections, tendon exposures, toe amputation and systemic reactions from absorption of chemical. One patient died from a chemical scald burn to 98% of the body surface area. Conclusions The key principles in the management of chemical burns include removal of the chemical, copious irrigation, limited use of antidotes, correct estimation of the extent of injury, identification of systemic toxicity, treatment of ocular contacts and management of chemical inhalation injury. Individualized treatment is emphasized. PMID:8640619

Cartotto, Robert C.; Peters, Walter J.; Neligan, Peter C.; Douglas, Leith G.; Beeston, Jeff

1996-01-01

271

Serum Prolactin and Growth Hormone in Holstein Bulls1  

Microsoft Academic Search

Repeatabilities among three estimates of serum prolactin and growth hormone collected in 71 Holstein bulls within 10 days were .13 and .30. However, befit- abilities of the serum hormone concen- trations were not different from 0. In another experiment of 86 Holstein bulls, serum collected in July contained more than twice as much prolactin as serum collected in January whereas

H. A. Tucker; J. A. Koprowski; J. H. Britt; W. D. Oxender

1974-01-01

272

Early detection of acute renal failure by serum cystatin C  

Microsoft Academic Search

Early detection of acute renal failure by serum cystatin C.BackgroundAcute renal failure (ARF) is associated with high mortality. Presently, no specific therapy for ARF exists. Therefore, early detection of ARF is critical to prevent its progression. However, serum creatinine, the standard marker to detect ARF, demonstrates major limitations. We prospectively evaluated whether serum cystatin C detected ARF earlier than serum

STEFAN HERGET-ROSENTHAL; GÜNTER MARGGRAF; JOHANNES HÜSING; FRAUKE GÖRING; FRANK PIETRUCK; ONNO JANSSEN; THOMAS PHILIPP; ANDREAS KRIBBEN

2004-01-01

273

The contribution of hepatic inactivation of testosterone to the lowering of serum testosterone levels by ketoconazole.  

PubMed

Hepatic biotransformation processes can be modulated by chemical exposure and these alterations can impact the biotransformation of endogenous substrates. Furthermore, chemically mediated alterations in the biotransformation of endogenous steroid hormones have been implicated as a mechanism by which steroid hormone homeostasis can be disrupted. The fungicide ketoconazole has been shown to lower serum testosterone levels and alter both gonadal synthesis and hepatic inactivation of testosterone. The present study examined whether the effects of ketoconazole on the hepatic biotransformation of testosterone contribute to its lowering of serum testosterone levels. Results also were used to validate further the use of the androgen-regulated hepatic testosterone 6alpha/15alpha-hydroxylase ratio as an indicator of androgen status. Male CD-1 mice were fed from 0 to 160 mg/kg ketoconazole in honey. Four h after the initial treatment, serum testosterone levels, gonadal testosterone secretion, and hepatic testosterone hydroxylase activity decreased, and the hepatic testosterone 6alpha/15alpha-hydroxylase ratio increased in a dose-dependent manner. Immunoblot analysis indicated that the transient decline in hepatic biotransformation was not due to reduced P450 protein levels. Rather, hepatic testosterone biotransformation activities were found to be differentially susceptible to direct inhibition by ketoconazole. Differential inhibition was also responsible for the increase seen in the 6alpha/15alpha-hydroxylase ratio. The changes in serum testosterone levels could be explained by decreased gonadal synthesis of testosterone and were not impacted by decreased hepatic biotransformation of testosterone. These results demonstrate that changes in the hepatic hydroxylation of testosterone by ketoconazole, and perhaps other chemicals, have little or no influence serum testosterone levels. PMID:10746940

Wilson, V S; LeBlanc, G A

2000-03-01

274

Biospeciation of various antidiabetic V(IV)O compounds in serum.  

PubMed

The interactions of various insulin mimetic oxovanadium(IV) compounds with serum proteins were studied in model systems and in ex vivo samples. For the modeling study, an earlier in situ method was extended and applied to the formation of ternary complexes of apotransferrin (apoTf)-V(IV)O-maltol (mal) and 1,2-dimethyl-3-hydroxy-4(1H)-pyridinone (dhp). Both systems were evaluated via simultaneous CD and EPR measurements. Determination of the formation constants of the ternary complexes allowed the calculation of more accurate stability constants for the V(IV)O-apoTf parent complexes and establishment of a better model for drug speciation in serum. It was found that dhp and the synergistic carbonate are non-competitive binders. Based on the stability constants obtained for V(IV)O-apoTf complexes and estimated for V(IV)O-HSA (= human serum albumin), modeling calculations were performed on the distribution of V(IV)O among the components of blood serum. The results were confirmed by HPLC-ICP-MS (liquid chromatography-inductively coupled plasma spectroscopy-mass spectrometry) measurements. The ex vivo interactions of the V(IV)O complexes formed with mal, picolinic acid (pic) and dhp with serum protein standards and also with human serum samples were evaluated. The proteins were firstly separated by (HPLC), and the V content of each fraction was determined by ICP-MS. All the studied V(IV)O compounds displayed similar chromatographic profiles, associated almost exclusively with apotransferrin as predicted by the modeling calculations. Under physiological conditions, the interactions with HSA of all of the species under study were negligible. Therefore Tf seems to be the main V(IV)O transporter in the serum under in vitro conditions, and this association is practically independent of the chemical form in which V(IV)O is administered. PMID:19290378

Jakusch, Tamás; Hollender, Dominik; Enyedy, Eva Anna; González, Cristina Sánchez; Montes-Bayón, Maria; Sanz-Medel, Alfredo; Costa Pessoa, Joăo; Tomaz, Isabel; Kiss, Tamás

2009-04-01

275

[Chemical weapons and chemical terrorism].  

PubMed

Chemical Weapons are kind of Weapons of Mass Destruction (WMD). They were used large quantities in WWI. Historically, large quantities usage like WWI was not recorded, but small usage has appeared now and then. Chemical weapons are so called "Nuclear weapon for poor countrys" because it's very easy to produce/possession being possible. They are categorized (1) Nerve Agents, (2) Blister Agents, (3) Cyanide (blood) Agents, (4) Pulmonary Agents, (5) Incapacitating Agents (6) Tear Agents from the viewpoint of human body interaction. In 1997 the Chemical Weapons Convention has taken effect. It prohibits chemical weapons development/production, and Organization for the Prohibition of Chemical Weapons (OPCW) verification regime contributes to the chemical weapons disposal. But possibility of possession/use of weapons of mass destruction by terrorist group represented in one by Matsumoto and Tokyo Subway Sarin Attack, So new chemical terrorism countermeasures are necessary. PMID:16296384

Nakamura, Katsumi

2005-10-01

276

Chemical Bonds  

NSDL National Science Digital Library

Electrons are key to forming the two broad categories of chemical bonds: covalent and ionic. Atoms, which have a nucleus surrounded by electrons, are represented in several different ways. In the Chemical Bonds activity, students explore the different kinds of chemical bonds that can form, ranging from non-polar covalent to ionic. In the model depicted above students adjust the electronegativity of two atoms and see the effect it has on electron distribution and bond type.

The Concord Consortium

2011-12-11

277

Chemical microsensors  

DOEpatents

An article of manufacture is provided including a substrate having an oxide surface layer and a selective thin film of a cyclodextrin derivative chemically bound upon said substrate, said film is adapted for the inclusion of a selected organic compound therewith. Such an article can be either a chemical sensor capable of detecting a resultant mass change from inclusion of the selected organic compound or a chemical separator capable of reversibly selectively separating a selected organic compound.

Li, DeQuan (Los Alamos, NM); Swanson, Basil I. (Los Alamos, NM)

1995-01-01

278

Serum cystatin C measured by automated immunoassay: A more sensitive marker of changes in GFR than serum creatinine  

Microsoft Academic Search

Serum cystatin C measured by automated immunoassay: A more sensitive marker of changes in GFR than serum creatinine. Serum cystatin C has been suggested as a new marker of GFR. For the introduction of this marker into clinical use a rapid and automated method is required. We have developed and validated an assay for serum cystatin C using latex particle-enhanced

David J Newman; Hansa Thakkar; Robert G Edwards; Martin Wilkie; Thomas White; Anders O Grubb; Christopher P Price

1995-01-01

279

Effects of serum amyloid A protein (SAA) on composition, size, and density of high density lipoproteins in subjects with myocardial infarction  

Microsoft Academic Search

The acute phase reactant serum amyloid A protein (SAA) circulates in plasma as a constituent of high density lipo- proteins (HDL). Advantage has been taken of the induction of SAA in human subjects with myocardial infarction to study the effect of SAA on the physical and chemical properties of HDL. HDL were isolated by sequential ultracentrifugation and assayed for chemical

Peter M. Clifton; A. Malcolm Mackinnon; Phillip J. Barter

280

Serum bleomycin-detectable iron in patients with thalassemia major with normal range of serum iron.  

PubMed

"Free" iron, a potentially radical-generating low mass iron, and not found in normal human blood, was increased in the serum of blood-transfused thalassemia major patients seen in the Yangon General Hospital, Yangon, Myanmar (Burma). The low mass iron was detected by the bleomycin assay. Fifty-one blood samples were analyzed (from 28 males and 23 females). High "free" iron was detected in 47 sera samples from thalassemia patients. Serum ferritin, which reflects the body store iron, was higher than the normal range (10-200 ng/ml) in 49 patients. On the other hand, serum iron of 39 sera samples fell within the normal range (50-150 micrograms/dl). Four were less than 50 micrograms/dl and eight were more than 150 micrograms/dl. Almost all the patients' sera of normal or higher serum iron level contained "free" iron. Thus, almost all the sera from thalassemic patients from Myanmar contain bleomycin-detectable iron, even when serum iron is within the normal range. In developing countries where undernutrition is prevalent (serum albumin in these patients was 3.6 +/- 0.4 g/dl, P < 0.0001 vs. control value of 4.0 - 4.8 g/dl), normal serum iron does not preclude the presence of free iron in the serum. PMID:7545860

Han, K E; Okada, S

1995-06-01

281

How to estimate GFR-serum creatinine, serum cystatin C or equations?  

Microsoft Academic Search

Plasma or serum creatinine is the most commonly used diagnostic marker for the estimation of glomerular filtration rate (GFR) in clinical routine. Due to substantial pre-analytical and analytical interferences and limitations, creatinine cannot be considered accurate. Besides, the diagnostic sensitivity to detect moderate GFR reduction is insufficient. Equations to estimate GFR based on serum creatinine have been introduced, which included

Stefan Herget-Rosenthal; Arend Bökenkamp; Walter Hofmann

2007-01-01

282

A comparison of the effects of estrus cow serum and fetal calf serum on in vitro  

E-print Network

maturation / oocyte INTRODUCTION The use of in vitro matured (IVM) oocytes in in vitro fertilization (IVFA comparison of the effects of estrus cow serum and fetal calf serum on in vitro nuclear maturation on Cytogenetics of Domestic Animals; Toulouse-Auzeville, 10-13 July 1990) cattle / female meiosis / in vitro

Boyer, Edmond

283

Use of synthetic serum-free medium for culture of human dermal fibroblasts to establish an experimental system similar to living dermis.  

PubMed

In this study, we sought to establish a defined experimental system for fibroblast growth similar to that of the living dermis. To this end, we evaluated the growth and biochemical characteristics of fibroblasts cultured with serum-free HFDM-1, a finely tuned synthetic medium for human fibroblast culture. Three culture conditions were used to grow fibroblasts obtained from primary culture: (1) culture with Dulbecco's modified Eagle medium (DMEM) plus 10 % fetal bovine serum (serum-supplemented DMEM), (2) culture with DMEM (serum-free DMEM), and (3) culture with HFDM-1 (HFDM-1), and fibroblast morphology, growth, collagen type I production, and lipid composition were analyzed. Fibroblasts grown in HFDM-1 maintained cell numbers at nearly 100 % from days 14 to 21 and produced more collagen type I than cells grown in serum-supplemented and serum-free DMEM. Arachidonic acid (20:4) and total polyunsaturated fatty acids were lower in cells grown in serum-free DMEM and HFDM-1 than in serum-supplemented DMEM. These results suggested that HFDM-1 recapitulated growth conditions in the dermis better than traditional, serum-supplemented DMEM. In addition, the controlled chemical composition of HFDM-1 eliminated a potential source of variability in cell culture conditions. PMID:24585098

Ejiri, Hirotaka; Nomura, Tadashi; Hasegawa, Masumi; Tatsumi, Chiaki; Imai, Midori; Sakakibara, Shunsuke; Terashi, Hiroto

2015-05-01

284

Comparison of Two Different Methods for Inactivation of Viruses in Serum  

Microsoft Academic Search

In order to compare protocols for inactivation of viruses potentially present in biological specimens, three different model viruses were treated in bovine serum by two different inactivation methods: samples were subjected either to chemical inactivation with ethylenimine (EI) at concentrations of 5 and 10 mM at 37°C for periods up to 72 h or to electron-beam irradiation in frozen and

T. PREUSS; S. KAMSTRUP; N. C. KYVSGAARD; P. NANSEN; A. MILLER; J. C. LEI

1997-01-01

285

Variation in Hematological and Serum Biochemical Values of the Mountain Brushtail Possum, Trichosuruscaninus Ogilby (Marsupialia: Phalangeridae)  

Microsoft Academic Search

Hematological and serum bio- chemical values were determined in a wild population of the mountain brushtail possum (Trichosuru.s caninu.s) at Cambarville, central Victoria, southeastern Australia. Animals were sampled during two-week trapping periods in Jtine, September, and December 1992, and April 1993. Values for hemoglobin, red cell count and hematocrit were significantly higher in males than females. Total protein and mean

K. L. Vlggers; D. B. Llndenmayer

1996-01-01

286

Proteomics and Bioinformatics Approaches for Identification of Serum Biomarkers to Detect Breast Cancer  

Microsoft Academic Search

Background: Surface-enhanced laser desorption\\/ioniza- tion (SELDI) is an affinity-based mass spectrometric method in which proteins of interest are selectively adsorbed to a chemically modified surface on a biochip, whereas impurities are removed by washing with buffer. This technology allows sensitive and high- throughput protein profiling of complex biological specimens. Methods: We screened for potential tumor biomarkers in 169 serum samples,

Jinong Li; Zhen Zhang; Jason Rosenzweig; Young Y. Wang; Daniel W. Chan

2002-01-01

287

Chemical Name  

Cancer.gov

Attachment III Chemical Quick Reference Chart for Minors Chemical Name Select Carcinogen Reproductive Toxin LD50 < 50 mg/kg (oral rat) LD50 < 200 mg/kg for 24 hours or less (dermal rabbit) LC50 < 200 ppm or 2 mg/L for one hour (inhalation rat)

288

Chemical Reactions  

NSDL National Science Digital Library

We don't often stop to think about it, but underlying many of our everyday activities are chemical reactions. From the cooking of an egg to the growth of a child, chemical reactions make things happen. Although many of the reactions that support our lives

National Science Teachers Association (NSTA)

2009-05-01

289

Chemical Linkage  

Microsoft Academic Search

IN the Research Items in NATURE of October 20, certain arguments are advanced in opposition to the views which we expressed in a recent paper published in the Journal of the Chemical Society, and without going into detail we wish to take the opportunity of pointing out that : (1) We cannot call to mind any evidence, chemical or physical,

R. F. Hunter; R. Samuel

1934-01-01

290

Serum adenosine deaminase activity in cutaneous anthrax  

PubMed Central

Background Adenosine deaminase (ADA) activity has been discovered in several inflammatory conditions; however, there are no data associated with cutaneous anthrax. The aim of this study was to investigate serum ADA activity in patients with cutaneous anthrax. Material/Methods Sixteen patients with cutaneous anthrax and 17 healthy controls were enrolled. We measured ADA activity; peripheral blood leukocyte, lymphocyte, neutrophil, and monocyte counts; erythrocyte sedimentation rate; and C reactive protein levels. Results Serum ADA activity was significantly higher in patients with cutaneous anthrax than in the controls (p<0.001). A positive correlation was observed between ADA activity and lymphocyte counts (r=0.589, p=0.021) in the patient group. Conclusions This study suggests that serum ADA could be used as a biochemical marker in cutaneous anthrax. PMID:24997584

Sunnetcioglu, Mahmut; Karadas, Sevdegul; Aslan, Mehmet; Ceylan, Mehmet Resat; Demir, Halit; Oncu, Mehmet Resit; Karahocagil, Mustafa Kas?m; Sunnetcioglu, Aysel; Aypak, Cenk

2014-01-01

291

Developmental toxicity and serum levels of perfluorononanoic acid in the wild-type and PPAR-alpha knockout mouse after gestational exposure  

EPA Science Inventory

Perfluorononanoic acid (PFNA) is a perfluoroalkyl acid detected in.the environment and in tissues of humans and wildlife. PFNA activates peroxisome proliferator-activated receptor-alpha (PPARa) in vitro and negatively impacts development and survival of CD1 mice. Our objective wa...

292

Serum immunoglobulins in calcific pancreatitis 1  

PubMed Central

Serum immunoglobulin concentrations were measured in 40 patients with calcific pancreatitis. A significant elevation of the mean serum IgA and IgG concentration when compared with a control group was found. The IgA was raised in 50% and the IgG in 27·5% when the individual results were assessed. The IgA did not appear to be of the secretory type. The possible significance of the raised IgA and IgG is discussed with reference to local pancreatic IgA production, autoimmune factors in chronic pancreatitis, and the ductal protein plugs in this disease. PMID:4752035

Bank, Simmy; Novis, B. H.; Petersen, E.; Dowdle, E.; Marks, I. N.

1973-01-01

293

Thermal diffusivity of human serum and plasma  

NASA Astrophysics Data System (ADS)

Using a thermal lens experimental set up, the thermal diffusivity of human serum and plasma were measured. Several samples were studied and the results are reported as the average, including the standard deviation. The samples of serum and plasma were obtained in healthy adult donors from the Guanajuato State Blood Transfusion Center, Mexico; the donors were clinically tested and they were free of hepatitis, AIDS and other infectious diseases. The parameters reported were obtained using the thermal lens aberrant model with the lasers arranged in the mismatched mode.

Mayén-Mondragón, R.; Yánez-Limón, J. M.; Palomares, P.; Sosa, M.; Bernal-Alvarado, J.

2005-06-01

294

Depletion of TGF-? from fetal bovine serum  

PubMed Central

TGF-? is one of the key cytokines controlling immune responses. Measuring TGF-? from culture supernatants in vitro is an important index of immune function. However, fetal bovine serum (FBS) contains a high level of latent TGF-? that often hampers measuring T cell-derived TGF-? in culture using FBS-supplemented medium. In this report, we generated anti-latency associated peptide (LAP) monoclonal antibodies which cross-react with bovine LAP, and developed a protocol to deplete TGF-? from FBS. This provides the ability to reliably quantify TGF-? in vitro without relying on serum-free media which do not support growth of murine T cells. PMID:20837018

Oida, Takatoku; Weiner, Howard L.

2010-01-01

295

Effect of anticoagulants and storage temperatures on stability of plasma and serum hormones 1 1 Preparation of “pink ice”: 186 g ammonium chloride (industrial grade, Harcoss Chemicals, Christchurch) dissolved in 814 g water and sufficient rhodamine B added to colour the solution pink. When frozen this 18.6% solution melts at ?15.8 °C and since it is the eutectic mixture it maintains this temperature until it is nearly all melted  

Microsoft Academic Search

Objectives: To determine the effect of different anticoagulants and storage conditions on the stability of hormones in plasma and serum.Design and methods: Human blood samples were collected from volunteers into EDTA, lithium heparin, sodium fluoride\\/potassium oxalate, or tubes without anticoagulant, plasma and serum left at ?20°C, 4°C or 30°C for 24 and 120 hours then assayed for ACTH, aldosterone, ?-subunit,

Margaret J Evans; John H Livesey; M. Jane Ellis; Timothy G Yandle

2001-01-01

296

Concentrations and trends of perfluorinated chemicals in potential indoor sources from 2007 through 2011 in the US.  

PubMed

Certain perfluorinated chemicals (PFCs) in consumer products used indoors are potential indoor PFCs sources and have been associated with developmental toxicity and other adverse health effects in laboratory animals (Lao et al., 2007). The concentrations of selected PFCs including perfluorooctanoic acid (PFOA) and other perfluorocarboxylic acids (PFCAs), in 35 selected consumer products that are commonly used in indoors were measured from the year of 2007 through 2011. The products collected included carpet, commercial carpet-care liquids, household carpet/fabric-care liquids, treated apparel, treated home textiles, treated non-woven medical garments, floor waxes, food-contact paper, membranes for apparel, and thread-sealant tapes. They were purchased from retail outlets in the United States between March 2007 and September 2011. The perfluorocarboxylic acid (PFCA) contents in the products have shown an overall downward trend. However, PFOA (C8) could still be detected in many products that we analyzed. Reductions of PFCAs were shown in both short-chain PFCAs (sum of C4 to C7) and long-chain PFCAs (sum of C8 to C12) over the study period. There were no significant changes observed between short-chain PFCAs and long-chain PFCAs. Fourteen products were analyzed to determine the amounts of perfluoroalkyl sulfonates (PFASs) they contained. These limited data show the pronounced increase of perfluoro-butane sulfonate (PFBS), an alternative to perfluorooctanoic sulfonate (PFOS), in the samples. A longer and wider range of study will be required to confirm this observed trend. PMID:24268172

Liu, Xiaoyu; Guo, Zhishi; Krebs, Kenneth A; Pope, Robert H; Roache, Nancy F

2014-03-01

297

ORIGINAL ARTICLE Serum apolipoprotein B predicts dyslipidemia,  

E-print Network

of Cardiology, Turkey; 2 Department of Public Health, Cerrahpas-a Medical Faculty, Istanbul University, Turkey for Cardiovascular Surgery, Istanbul, Turkey Objectives: To investigate the role of serum apolipoprotein (apo) B: Apo B values exhibited no significant difference among sexes. Low-density lipoprotein (LDL

Cai, Long

298

Serum lipids and cardiovascular reactivity to stress  

Microsoft Academic Search

Several studies have reported an association between serum lipid levels and cardiovascular reactivity to laboratory stressors. Their findings, however, are equivocal. The inconsistencies may be due to shortcomings such as the small number of subjects, the inclusion of patient groups, no control for medication, and no control for age effects. Two studies are presented investigating the relationship in large groups

Lorenz J. P. van Doornen; Harold Snieder; Dorret I. Boomsma

1998-01-01

299

Antifungal serum concentration monitoring: an update  

Microsoft Academic Search

Invasive fungal infections (IFIs) are occurring with increasing incidence and are associated with sig- nificant morbidity and mortality. Understanding the relationship between the pharmacokinetic and pharmacodynamic properties of antifungals is essential to optimize the potential for favourable clinical and microbiological outcomes while minimizing risks of treatment-related toxicity. Antifungal serum concentrations may aid in the determination of appropriate dosing in select

Megan L. Goodwin; Richard H. Drew

2008-01-01

300

Cocaine Use Disorders and Serum Magnesium Profile  

Microsoft Academic Search

Introduction: Magnesium influences the nervous system via its actions on the release and metabolism of neurotransmitters, and abnormal magnesium metabolism has been implicated in several neuropsychiatric disorders with prominent mood symptoms. The aim of this study was to compare the serum levels of magnesium of cocaine addicts to those of heroin addicts and normal controls. We also attempted to clarify

F. Tonioni; G. Martinotti; A. Barra; D. Martinelli; G. Autullo; C. Rinaldi; D. Tedeschi; L. Janiri; P. Bria

2009-01-01

301

Exercise and Serum Androgens in Women.  

ERIC Educational Resources Information Center

This study examining the effect of a 10-week hydraulic resistance exercise program on serum androgen levels, strength, and lean body weight in 18 college women revealed that training did not result in significant increases in androgen hormones, although there were significant gains in strength. (Author/CB)

Westerlind, Kim C.; And Others

1987-01-01

302

Serum amyloid P inhibits dermal wound healing  

Technology Transfer Automated Retrieval System (TEKTRAN)

The repair of open wounds depends on granulation tissue formation and contraction, which is primarily mediated by myofibroblasts. A subset of myofibroblasts originates from bone-marrow-derived monocytes which differentiate into fibroblast-like cells called fibrocytes. Serum amyloid P (SAP) inhibits ...

303

Serum lipid levels in seasonal affective disorder.  

PubMed

Previous research has assessed the relationship between blood lipid levels and depression with contradictory results. Several studies have linked low cholesterol levels with impulsive, aggressive and suicidal behaviours. The aim of this pilot study was to examine serum lipids in a sample of patients suffering from seasonal affective disorder (SAD). We conducted a retrospective analysis of data on total serum cholesterol and serum triglycerides in 39 SAD patients and 40 non-seasonally depressed or schizophrenic control subjects. Study subjects had to be free of psychotropic drugs for at least 2 weeks. Analysis of covariance (ANCOVA) was performed to assess group differences. After adjustment for significant covariates SAD patients had significantly lower total cholesterol levels (5.21 +/- 1.14 mmol/l) than control subjects (5.94 +/- 1.11 mmol/l; p = 0.013). Moreover, hypercholesterolemia (total cholesterol > 5.20 mmol/l) was significantly less frequent in the SAD group (46.2%) than in the control group (75.0%; p = 0.012). Total serum triglycerides did not differ significantly between SAD patients (1.54 +/- 1.07 mmol/l) and controls (1.56 +/- 0.96 mmol/l; p = 0.126). The results of this study support the idea that low cholesterol levels may be of pathogenetic importance in SAD. Further study in larger clinical samples is warranted to clarify our findings. PMID:17149538

Pjrek, Edda; Winkler, Dietmar; Abramson, David W; Konstantinidis, Anastasios; Stastny, Jürgen; Willeit, Matthäus; Praschak-Rieder, Nicole; Kasper, Siegfried

2007-06-01

304

Serum transferrin receptor measurements in hematologic malignancies.  

PubMed

An enzyme-linked immunosorbent assay using specific monoclonal antibodies was used to measure circulating transferrin receptor (TR) in 87 patients with various hematologic malignancies. The mean serum TR was significantly elevated in patients with myeloproliferative disorders (15.47 +/- 12.54 micrograms/ml), whereas there were no differences in chronic granulocytic leukemia (7.89 +/- 3.56 micrograms/ml), myelodysplastic disorders (9.25 +/- 4.73 micrograms/ml), and acute nonlymphocytic leukemia (3.85 +/- 3.50 micrograms/ml) as compared to normal (5.63 +/- 1.42 micrograms/ml). Among patients with lymphoproliferative disorders, the mean level was normal in lymphoma (5.73 +/- 2.59 micrograms/ml), multiple myeloma (5.47 +/- 1.31 micrograms/ml), and hairy cell leukemia (7.04 +/- 3.69 micrograms/ml). The serum TR was significantly elevated in chronic lymphocytic leukemia (CLL; 14.17 +/- 12.29 micrograms/ml), and the serum levels reflected the clinical stage of the disease. These findings suggest that serum TR measurement may provide a useful laboratory index of disease activity in certain disorders such as CLL, whereas it most likely reflects the intensity of erythropoiesis in the remaining hematological disorders that were evaluated in this study. PMID:2163585

Klemow, D; Einsphar, D; Brown, T A; Flowers, C H; Skikne, B S

1990-07-01

305

Abnormalities of serum calcium and magnesium  

Technology Transfer Automated Retrieval System (TEKTRAN)

Neonatal hypocalcemia is defined as a total serum calcium concentration of <7 mg/dL or an ionized calcium concentration of <4 mg/dL (1mmol/L). In very low birth weight (VLBW) infants, ionized calcium values of 0.8 to 1 mmol/L are common and not usually associated with clinical symptoms. In larger in...

306

Unnecessary Chemicals  

ERIC Educational Resources Information Center

Discusses the health hazards resulting from chemical additions of many common products such as cough syrups, food dyes, and cosmetics. Steps being taken to protect consumers from these health hazards are included. (MDR)

Johnson, Anita

1978-01-01

307

Chemical Weathering  

NSDL National Science Digital Library

This tombstone weathering lab is designed to provide students with tangible understanding of chemical weathering and weathering rates. To prepare for this lab, students will have learned in previous labs to identify common minerals and rocks and will have attended lectures about the process of chemical weathering. During the first part of the lab we travel to the city cemetery to collect data on the age and extent of chemical weathering of tombstones that are made of limestone and igneous rocks. After collecting data for ~1 hour, we return to the computer lab where students use Microsoft Excel to analyze and interpret their data. Their task is to calculate a chemical weathering rate for limestone for our region and compare that rate to those from other regions. This activity gives students experience in the process of scientific inquiry: data collection, data analysis and data interpretation. Students develop Microsoft Excel skills: writing formulas, producing charts, understanding trendlines and R2 values.

Kira Lawrence

308

Chemical Emergency  

MedlinePLUS

... Landslide Pet Safety Poisoning Power Outage Terrorism Thunderstorm Tornado Tsunami Volcano Water Safety Wildfire Winter Storm Tools ... and your family is to be prepared. In Case of Poisoning The most common home chemical emergencies ...

309

Chemical sensors  

DOEpatents

Sensors responsive to small changes in the concentration of chemical species are disclosed, comprising a mechanicochemically responsive polymeric film capable of expansion or contraction in response to a change in its chemical environment, either operatively coupled to a transducer capable of directly converting the expansion or contraction to a measurable electrical or optical response, or adhered to a second inert polymeric strip, or doped with a conductive material. 12 figs.

Lowell, J.R. Jr.; Edlund, D.J.; Friesen, D.T.; Rayfield, G.W.

1992-06-09

310

SERUM-MEDIATED LEUKEMIA CELL DESTRUCTION IN AKR MICE  

PubMed Central

AKR mice with spontaneous leukemia were infused with normal serum from a variety of species. Leukemia cell destruction was produced by serum from strains of mice possessing the full spectrum of complement components, but not by serum from strains with a genetically determined deficiency of C5. Serum from guinea pigs, horses, and humans also causes destruction of leukemia cells. The antileukemic factor in normal serum was heat labile (56°C for 35 min) and could be inactivated by cobra venom factor (CVF). Tests of individual complement factors from guinea pig serum and from human serum suggest that C5 is the antileukemic complement component in normal serum. Evidence was obtained that complement also plays a role in the antileukemic effect of interferon and endotoxin. PMID:4744012

Kassel, Robert L.; Old, Lloyd J.; Carswell, Elizabeth A.; Fiore, Nancy C.; Hardy, William D.

1973-01-01

311

9 CFR 147.2 - The rapid serum test. 2  

Code of Federal Regulations, 2014 CFR

...rapid serum test. 2 147.2 Section 147.2 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT...PROVISIONS ON NATIONAL POULTRY IMPROVEMENT PLAN Blood Testing Procedures § 147.2 The rapid serum...

2014-01-01

312

Identification of phthalate esters in the serum of young Puerto Rican girls with premature breast development.  

PubMed Central

Premature breast development (thelarche) is the growth of mammary tissue in girls younger than 8 years of age without other manifestations of puberty. Puerto Rico has the highest known incidence of premature thelarche ever reported. In the last two decades since this serious public health anomaly has been observed, no explanation for this phenomenon has been found. Some organic pollutants, including pesticides and some plasticizers, can disrupt normal sexual development in wildlife, and many of these have been widely used in Puerto Rico. This investigation was designed to identify pollutants in the serum of Puerto Rican girls with premature thelarche. A method for blood serum analysis was optimized and validated using pesticides and phthalate esters as model compounds of endocrine-disrupting chemicals. Recovery was > 80% for all compounds. We performed final detection by gas chromatography/mass spectrometry. We analyzed 41 serum samples from thelarche patients and 35 control samples. No pesticides or their metabolite residues were detected in the serum of the study or control subjects. Significantly high levels of phthalates [dimethyl, diethyl, dibutyl, and di-(2-ethylhexyl)] and its major metabolite mono-(2-ethylhexyl) phthalate were identified in 28 (68%) samples from thelarche patients. Of the control samples analyzed, only one showed significant levels of di-isooctyl phthalate. The phthalates that we identified have been classified as endocrine disruptors. This study suggests a possible association between plasticizers with known estrogenic and antiandrogenic activity and the cause of premature breast development in a human female population. PMID:11017896

Colón, I; Caro, D; Bourdony, C J; Rosario, O

2000-01-01

313

Detection limits of organochlorine pesticides and related compounds in blood serum  

SciTech Connect

Determinations of organochlorine pesticides and similar chemical residues in blood serum have often reported detection limits of 1 ng/mL. When a study group has incurred body burdens lower than this, underestimates and misclassifications of exposure may occur because persons with pesticide residue concentration below the limit of detection are usually treated as zeros.' Thus in order to more accurately assess exposures in such populations, analysis of adipose tissue has been done. Recently, with TCDD, use of a sufficient volume of serum, as much as 0.5 L, in conjunction with appropriate analytical techniques has been shown to achieve detection limits necessary for epidemiological assessments, i.e., comparable to analysis of adipose tissue. In a population-based study involving children in which the authors were involved, it was not feasible to obtain specimens of either adipose or a large volume of serum. There was no compelling health motivation for such measures, nor did they wish to impair participation rates. Therefore, they chose to optimize the existing serum analysis, in order to achieve a detection limit low enough to assess reasonably the anticipated exposures.

Wolff, M.S.; Rivera, M.; Baker, D.B. (Mount Sinai School of Medicine, New York, NY (United States))

1991-10-01

314

Temporal variability of polybrominated diphenyl ether (PBDE) serum concentrations over one year.  

PubMed

Polybrominated diphenyl ethers (PBDEs) are flame retardant chemicals used in consumer products. They are common contaminants in human serum and associated with adverse health effects. Our objectives were to characterize PBDE serum concentrations in a New England cohort and assess temporal variability of this exposure biomarker over a one-year period. We collected three repeated measurements at six-month intervals from 52 office workers from the greater Boston (MA, United States) area from 2010 to 2011. The intraclass correlation coefficient for BDEs 28, 47, 99, 100, and 153 ranged from 0.87 to 0.99, indicating that a single serum measurement can reliably estimate exposure over a one-year period. This was true for both lipid adjusted and nonlipid adjusted concentrations. The kappa statistics, quantifying the level of agreement of categorical exposure classification, based on medians, tertiles, or quartiles ranged from 0.67 to 0.90. Some congeners showed nonsignificant increases from sampling round 1 (winter) to round 2 (summer) and significant decreases from round 2 to round 3 (winter). This study highlights the high reliability of a single serum PBDE measurement for use in human epidemiologic studies. PMID:25383963

Makey, Colleen M; McClean, Michael D; Sjödin, Andreas; Weinberg, Janice; Carignan, Courtney C; Webster, Thomas F

2014-12-16

315

Dye attached poly(hydroxyethyl methacrylate) cryogel for albumin depletion from human serum.  

PubMed

Cibacron Blue F3GA was immobilized on poly(hydroxyethyl methacrylate) cryogel and it was used for selective and efficient depletion of albumin from human serum. The poly(hydroxyethyl methacrylate) was selected as the basic component because of its inertness, mechanical strength, chemical and biological stability, and biocompatibility. Cibacron Blue F3GA was covalently attached to the poly(hydroxyethyl methacrylate) cryogel to produce poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel affinity column. The poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel was characterized with respect to gelation yield, swelling degree, total volume of macropores, Fourier Transform Infrared spectroscopy, and scanning electron microscopy. It was found that the maximum amount of adsorption (343 mg/g of dry cryogel) obtained from experimental results is very close to the calculated Langmuir adsorption capacity (345 mg/g of dry cryogel). The maximum adsorption capacity for poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel column was obtained as 950 mg/g of dry cryogel for nondiluted serum. The adsorption capacity decreased with increasing dilution ratios while the depletion ratio of albumin remained as 77% in serum sample. Finally, the poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel was optimized for using in the fast protein liquid chromatography system for rapid removal of the high abundant proteins from the human serum. PMID:22556120

Andac, Muge; Galaev, Igor; Denizli, Adil

2012-05-01

316

Serum ferritin concentration and iron stores in normal subjects  

Microsoft Academic Search

The relationship between serum ferritin concentration and the amount of storage iron has been studied in normal subjects. A high degree of correlation was demonstrated between serum ferritin concentration and storage iron measured by quantitative phlebotomy. The possible advantages of assessing iron stores by using the serum ferritin concentration are discussed.

G. O. Walters; F. M. Miller; M. Worwood

1973-01-01

317

Serum leptin levels in patients with nonalcoholic steatohepatitis  

Microsoft Academic Search

OBJECTIVE:Leptin is a peptide hormone that mainly regulates food intake and energy expenditure of human body. A close correlation between serum leptin levels and the percentage of body fat stores is well known. Nonalcoholic steatohepatitis (NASH) is a common disorder which causes serum liver enzyme elevation. In this study, the serum leptin levels were investigated in patients with NASH to

Ahmet Uygun; Abdurrahman Kadayifci; Zeki Yesilova; Ahmet Erdil; Halil Yaman; Mendane Saka; M. Salih Deveci; Sait Bagci; Mustafa Gulsen; Necmettin Karaeren; Kemal Dagalp

2000-01-01

318

Relation Between Micellar and Serum Casein in Bovine Milk1  

Microsoft Academic Search

Little or no additional casein dissolved when milk was diluted with large volumes of milk dialysate. Some dissolution of mi- cellar to serum casein occurred when sedi- mented micelles were redispersed in ultra- filtrate mechanically, but the concentration of serum casein remained far below that of the original milk. It is concluded that micellar and serum casein do not form

Dyson Rose

1968-01-01

319

Iron and ADHD: Time to Move beyond Serum Ferritin Levels  

ERIC Educational Resources Information Center

Objective: (a) To compare serum ferritin levels in a sample of stimulant-naive children with ADHD and matched controls and (b) to assess the association of serum ferritin to ADHD symptoms severity, ADHD subtypes, and IQ. Method: The ADHD and the control groups included 101 and 93 children, respectively. Serum ferritin levels were determined with…

Donfrancesco, Renato; Parisi, Pasquale; Vanacore, Nicola; Martines, Francesca; Sargentini, Vittorio; Cortese, Samuele

2013-01-01

320

Serum bilirubin: a prognostic factor in primary biliary cirrhosis  

Microsoft Academic Search

We followed up 55 patients with proven primary biliary cirrhosis for several years or until death. A graph of the level of serum bilirubin versus time that was constructed for each patient shows an initial period of variable length in which the serum bilirubin level remained constant. This was followed by a period of rapid rise in serum bilirubin which

J M Shapiro; H Smith; F Schaffner

1979-01-01

321

Nachweis spezifischer Placenta-Antigene im Serum Schwangerer  

Microsoft Academic Search

Summary To produce an anti-placenta serum rabbits were immunized with placenta extract. With the anti-placenta rabbit serum three different placenta antigens could be demonstrated in the placenta extract. These placenta antigens were also found in the serum of pregnant women with normal and disturbed pregnancies, further more in urine of pregnant women, liquor amnii, umbilical blood as well as in

H. Schultze-Mosgau; K. Fischer

1971-01-01

322

Elevation of serum acid phosphatase in cancers with bone metastasis  

Microsoft Academic Search

In patients with nonprostatic cancer, serum acid phosphatase activity is usually elevated when bone metastasis is present but not when bone metastasis is absent. The fraction responsible for serum enzyme elevation is a normal component of serum; it appears in gel electrophoresis as band 5; and is tartrate-resistant. It is suggested that the origin of acid phosphatase elevation is bone

Mehdi Tavassoli; Mercedes Rizo; Lung T. Yam

1980-01-01

323

Transition of serum vitellogenin cycle in Sakhalin taimen ( Hucho perryi)  

Microsoft Academic Search

A specific and sensitive enzyme-linked immunosorbent assay (ELISA) and a single radial immunodiffusion (SRID) were developed for measurement of serum vitellogenin (Vg) levels in Sakhalin taimen (Hucho perryi). Regarding specificity for serum Vg, an antiserum raised against lipovitellin of taimen (a-Lv) was adequate for both assays. ELISA and SRID could detect Vg in serum at concentrations as low as 10

Naoshi Hiramatsu; Munetaka Shimizu; Haruhisa Fukada; Makiko Kitamura; Kazuhiro Ura; Hirotoshi Fuda; Akihiko Hara

1997-01-01

324

BILIARY LIPIDS SUPPORT SERUM-FREE GROWTH OF 'GIARDIA LAMBLIA'  

EPA Science Inventory

Giardia lamblia has only been grown in vitro in media containing serum or serum fractions. How this pathogen can grow in the human small intestinal lumen without serum is not known. The authors found that samples of human hepatic or gall bladder bile maintained G. lamblia surviva...

325

Serum Antibody Repertoire Profiling Using In Silico Antigen Screen  

PubMed Central

Serum antibodies are valuable source of information on the health state of an organism. The profiles of serum antibody reactivity can be generated by using a high throughput sequencing of peptide-coding DNA from combinatorial random peptide phage display libraries selected for binding to serum antibodies. Here we demonstrate that the targets of immune response, which are recognized by serum antibodies directed against sequential epitopes, can be identified using the serum antibody repertoire profiles generated by high throughput sequencing. We developed an algorithm to filter the results of the protein database BLAST search for selected peptides to distinguish real antigens recognized by serum antibodies from irrelevant proteins retrieved randomly. When we used this algorithm to analyze serum antibodies from mice immunized with human protein, we were able to identify the protein used for immunizations among the top candidate antigens. When we analyzed human serum sample from the metastatic melanoma patient, the recombinant protein, corresponding to the top candidate from the list generated using the algorithm, was recognized by antibodies from metastatic melanoma serum on the western blot, thus confirming that the method can identify autoantigens recognized by serum antibodies. We demonstrated also that our unbiased method of looking at the repertoire of serum antibodies reveals quantitative information on the epitope composition of the targets of immune response. A method for deciphering information contained in the serum antibody repertoire profiles may help to identify autoantibodies that can be used for diagnosing and monitoring autoimmune diseases or malignancies. PMID:23826227

Liu, Xinyue; Hu, Qiang; Liu, Song; Tallo, Luke J.; Sadzewicz, Lisa; Schettine, Cassandra A.; Nikiforov, Mikhail; Klyushnenkova, Elena N.; Ionov, Yurij

2013-01-01

326

Platelet Lysate as Replacement for Fetal Bovine Serum in Mesenchymal Stromal Cell Cultures  

PubMed Central

Summary Mesenchymal stromal cells (MSC) emerged as highly attractive in cell-based regenerative medicine. Initially thought to provide cells capable of differentiation towards mesenchymal cell types (osteoblasts, chondrocytes, adipocytes etc.), by and by potent immunoregulatory and pro-regenerative activities have been discovered, broadening the field of potential applications from bone and cartilage regeneration to wound healing and treatment of autoimmune diseases. Due to the limited frequency in most tissue sources, ex vivo expansion of MSC is required compliant with good manufacturing practice (GMP) guidelines to yield clinically relevant cell doses. Though, still most manufacturing protocols use fetal bovine serum (FBS) as cell culture supplement to isolate and to expand MSC. However, the high lot-to-lot variability as well as risk of contamination and immunization call for xenogenic-free culture conditions. In terms of standardization, chemically defined media appear as the ultimate achievement. Since these media need to maintain all key cellular and therapy-relevant features of MSC, the development of chemically defined media is still – albeit highly investigated – only in its beginning. The current alternatives to FBS rely on human blood-derived components: plasma, serum, umbilical cord blood serum, and platelet derivatives like platelet lysate. Focusing on quality aspects, the latter will be addressed within this review. PMID:24273486

Bieback, Karen

2013-01-01

327

Symptomatic disc herniation and serum lipid levels  

Microsoft Academic Search

Insufficient blood supply to the intervertebral disc (IVD) has been proposed to play a role as causative factor in IVD degeneration.\\u000a There is an association between IVD diseases and increased risk of dying of ischaemic heart disease. Obesity and tobacco are\\u000a potential risk factors for degenerative IVD disease. High blood cholesterol and triglycerides serum levels are risk factors\\u000a for atherosclerosis,

Umile Giuseppe Longo; Luca Denaro; Filippo Spiezia; Francisco Forriol; Nicola Maffulli; Vincenzo Denaro

328

Serum gastrin level in early childhood  

Microsoft Academic Search

Serum gastrin concentration was measured in newborns and infants with no gastrointestinal disorders, in the fasting state and after food stimulation. Mean fasting concentration in 14 newborns aged 1 to 12 days (130 . 4 pg\\/ml +\\/- 11 . 4 SE) was significantly higher than the mean value in 23 infants aged 1.5 to 22 months (101.4 +\\/- 6.6 pg\\/ml).

L Sann; A P Chayvialle; A Bremond; R Lambert

1975-01-01

329

Serum protein electrophoresis in 147 dogs  

Microsoft Academic Search

Reference intervals for serum protein electrophoresis (SPE) were created from a group of 75 clinically healthy dogs and compared with SPE results obtained from clinical cases presented to the University of Bristol over an eight-and-a-half-year period. A total of 147 dogs, in which SPE had been performed, had complete case records available and thus met the inclusion criteria. Signalment and

S. W. Tappin; S. S. Taylor; S. Tasker; S. J. Dodkin; K. Papasouliotis; K. F. Murphy

2011-01-01

330

Roles of Serum Lectins in Host Defense  

Microsoft Academic Search

Mannan-binding protein (MBP), also called mannose-binding protein (MBP) or mannanbinding lectin (MBL), is a Ca2+-dependent (C-type) mammalian lectin specific for mannose, N-acetylglucosamine (GlcNAc), and fucose, and is an important serum component associated with innate immunity. Human MBP is\\u000a a homooligomer of an approximately 31 kDa subunit, each subunit containing a carbohydrate recognition domain (CRD) followed\\u000a by a short neck region

Nobuko Kawasaki; Bruce Yong Ma; Toshisuke Kawasaki

331

Pharmaceutical Strategies Utilizing Recombinant Human Serum Albumin  

Microsoft Academic Search

Gene manipulation techniques open up the possibility of making recombinant human serum albumin (rHSA) or mutants with desirable therapeutic properties and for protein fusion products. rHSA can serve as a carrier in synthetic heme protein, thus reversibly carrying oxygen. Myristoylation of insulin results in a prolonged half-life because of self aggregation and increased albumin binding. Preferential albumin uptake by tumor

Victor Tuan Giam Chuang; Ulrich Kragh-Hansen; Masaki Otagiri

2002-01-01

332

Serum angiotensin converting enzyme in pulmonary disease  

Microsoft Academic Search

Synthetic acylated tripeptides, which may or may not be radiolabelled, are generally used as substrates for measuring serum\\u000a angiotensin converting enzyme (SACE) activity. The capillary endothelial cells are the major source of SACE in normals and\\u000a certain diseased states, however Gaucher’s cells in Gaucher’s disease and epithelioid cells in granulomatous disorders, including\\u000a sarcoidosis, are the major source of enzyme in

P. K. Rohatgi

1982-01-01

333

Why do polyunsaturated fatty acids lower serum  

Microsoft Academic Search

Replacement of saturated by polyunsaturated fatty acids in the diet may lower serum very low-density and low-density lipoprotein concentrations because the liver preferentially converts polyunsaturated fatty acids into ketone bodies instead of into very low-density lipoprotein triglycerides. Thus unlike saturated fatty acids, polyunsaturated fatty acids are transported to the tissues for oxidation without leaving a trail of lipoprotein remnants in

Anion C Beynen; Martijn B Katan

334

Mammographic breast density and serum phytoestrogen levels.  

PubMed

Some forms of estrogen are associated with breast cancer risk as well as with mammographic density (MD), a strong marker of breast cancer risk. Whether phytoestrogen intake affects breast density, however, remains unclear. We evaluated the association between serum levels of phytoestrogens and MD in postmenopausal women. We enrolled 269 women, ages 55-70 yr, who received a screening mammogram and had no history of postmenopausal hormone use. Subjects completed a survey on diet and factors related to MD and provided a blood sample for analysis of 3 phytoestrogens: genistein, daidzein, and coumestrol. We examined whether mean percent MD was related to serum level of phytoestrogens, adjusting for age and body mass index. Genistein and daidzein levels correlated with self-reported soy consumption. Mean percent MD did not differ across women with different phytoestrogen levels. For example, women with nondetectable genistein levels had mean density of 11.0% [95% confidence intervals (CI) = 9.9-12.4], compared to 10.5% (95% CI = 8.0-13.7) and 11.2% (95% CI = 8.7-14.6) for < and ? median detectable levels, respectively. In a population with relatively low soy intake, serum phytoestrogens were not associated with mammographic density. Additional studies are needed to determine effects of higher levels, particularly given patterns of increasing phytoestrogen intake. PMID:22860715

Lowry, Sarah J; Sprague, Brian L; Aiello Bowles, Erin J; Hedman, Curtis J; Hemming, Jocelyn; Hampton, John M; Burnside, Elizabeth S; Sisney, Gale A; Buist, Diana S M; Trentham-Dietz, Amy

2012-08-01

335

Preliminary crystallographic studies of four crystal forms of serum albumin  

NASA Technical Reports Server (NTRS)

Several crystal forms of serum albumin suitable for three-dimensional structure determination have been grown. These forms include crystals of recombinant and wild-type human serum albumin, baboon serum albumin, and canine serum albumin. The intrinsic limits of X-ray diffraction for these crystals are in the range 0.28-0.22 nm. Two of the crystal forms produced from human and canine albumin include incorporated long-chain fatty acids. Molecular replacement experiments have been successfully conducted on each crystal form using the previously determined atomic coordinates of human serum albumin illustrating the conserved tertiary structure.

Carter, D. C.; Chang, B.; Ho, J. X.; Keeling, K.; Krishnasami, Z.

1994-01-01

336

Chemical Changes  

NSDL National Science Digital Library

This is an excellent resource for teachers and students. It offers countless lab ideas for teaching chemical and physical changes and is geared for fifth through eighth grade. It also gives interactive web addresses for students and includes PowerPoint presentations on this topic.

can& #39; t tell- a science educator- not affiliated with any specific organization

2011-10-10

337

Chemical separations  

SciTech Connect

This volume collects papers presented at a conference on chemical separation. Topics include: field-flow fractionation, chromatography, electrophoresis, solvent extraction in metals recovery, extraction of uranium and plutonium from nitric acid, modeling of flow fields in oscillating droplets, inclusion, and membrane processes.

King, J.C.; Navratil, J.D.

1986-01-01

338

Chemical Wonders  

NSDL National Science Digital Library

Students are introduced to chemical engineering and learn about its many different applications. They are provided with a basic introduction to matter and its different properties and states. An associated hands-on activity gives students a chance to test their knowledge of the states of matter and how to make observations using their five senses: touch, smell, sound, sight and taste.

Integrated Teaching and Learning Program,

339

Chemical Mahjong  

ERIC Educational Resources Information Center

An open-access, Web-based mnemonic game is described whereby introductory chemistry knowledge is tested using mahjong solitaire game play. Several tile sets and board layouts are included that are themed upon different chemical topics. Introductory tile sets can be selected that prompt the player to match element names to symbols and metric…

Cossairt, Travis J.; Grubbs, W. Tandy

2011-01-01

340

Delicious Chemicals.  

ERIC Educational Resources Information Center

This paper presents an approach to chemistry and nutrition that focuses on food items that people consider delicious. Information is organized according to three categories of food chemicals that provide energy to the human body: (1) fats and oils; (2) carbohydrates; and (3) proteins. Minerals, vitamins, and additives are also discussed along with…

Barry, Dana M.

341

Effect of oral glucose on serum zinc in the elderly  

SciTech Connect

To determine the effect of glucose loading on serum zinc concentrations, 34 elderly subjects aged 60-86 y were studied. Anthropometric data, medical and dietary histories were obtained. Serum zinc and glucose concentrations were obtained fasting and 1/2, 1, 1 1/2, 2 and 3 h after 75 g oral glucose load; glycohemoglobin and fasting serum lipids were also determined. For comparison, the subjects were categorized as: normal or low serum zinc concentrations; normal or high body mass index BMI; normal or high sum of skinfolds and normal or high serum cholesterol. Results showed that low serum zinc concentrations increased significantly over baseline values after the glucose load and did not return to fasting levels. On the other hand, mean serum zinc concentrations significantly declined without recovery for those with normal zinc values. For the total group, no significant differences were noted between fasting values and subsequent time periods. No correlations were noted between fasting serum zinc and area under the curve for zinc except in the high BMI group (positive correlation observed). For the high BMI group, fasting serum zinc differed significantly from the succeeding measurements except for 30 min. For the group as a whole, mean serum zinc concentration was within normal limits (76.9 +/- 2.8 mcg/ml): mean zinc intake was less than 2/3rds the RDA. They conclude that glucose ingestion may alter serum zinc and should be considered in interpreting these levels.

Lopez, A.L.; Kohrs, M.B.; Horwitz, D.L.; Cyborski, C.K.; Czajka-Narins, D.M.; Kamath, S.

1986-03-05

342

Serum levels of matrix metalloproteinases: implications in clinical neurology.  

PubMed

Matrix metalloproteinases (MMPs) are zinc-dependent enzymes involved in remodeling extracellular matrix and cell-matrix interactions. A pathogenic role of MMPs in neurological disorders is likely. This paper focuses on serological clinical aspects only. In multiple sclerosis, higher serum MMP-3 is seen during relapses. Lower serum MMP-8 and -9 levels correlate with fewer contrast-enhanced T(2)-weighted MRI lesions, and serum MMP-9 can be used in monitoring treatment. In myasthenia gravis, serum MMP-2, -3, and -9 levels are elevated in both generalized and ocular diseases. A proportion of the patients have markedly increased serum MMP-3. In acute stroke, higher serum MMP-9 correlates with larger infarct volume, stroke severity, and worse functional outcome, and serum MMP-3 is significantly lower than in several other neurological disorders and healthy controls. In amyotrophic lateral sclerosis, serum MMP-2 correlates with disease progression, and both serum MMP-1 and -2 are elevated. In Alzheimer's disease, serum MMP-3, -9, and -10 are elevated. In migraine, serum MMP-2 is elevated, and also MMP-9 in those patients with migraine without aura. MMP-9 is implicated in the pathogenesis of experimental epilepsy. A pathogenic role of MMPs in these conditions could be related to their ability to degrade extracellular matrix. MMPs may also facilitate autoimmunity. PMID:22262194

Romi, Fredrik; Helgeland, Geir; Gilhus, Nils Erik

2012-01-01

343

Embedded Piezoresistive Microcantilever Sensors for Chemical and Biological Sensing  

NASA Astrophysics Data System (ADS)

Microcantilever sensors based on embedded piezoresisative technology offer a promising, low-cost method of sensing chemical and biological species. Here, we present data on the detection of various gaseous analytes, including volatile organic compounds (VOC's) and carbon monoxide. Also, we have used these sensors to detect the protein bovine serum albumin (BSA), a protein important in the study of human childhood diabetes.

Porter, Timothy; Eastman, Michael; Kooser, Ara; Manygoats, Kevin; Zhine, Rosalie

2003-03-01

344

A Comparison of PBDE Serum Concentrations in Mexican and Mexican-American Children Living in California  

PubMed Central

Background: Polybrominated diphenyl ethers (PBDE), which are used as flame retardants, have been found to be higher in residents of California than of other parts of the United States. Objectives: We aimed to investigate the role of immigration to California on PBDE levels in Latino children. Methods: We compared serum PBDE concentrations in a population of first-generation Mexican-American 7-year-old children (n = 264), who were born and raised in California [Center for Health Analysis of Mothers and Children of Salinas (CHAMACOS) study], with 5-year-old Mexican children (n = 283), who were raised in the states in Mexico where most CHAMACOS mothers had originated (Proyecto Mariposa). Results: On average, PBDE serum concentrations in the California Mexican-American children were three times higher than their mothers’ levels during pregnancy and seven times higher than concentrations in the children living in Mexico. The PBDE serum concentrations were higher in the Mexican-American children regardless of length of time their mother had resided in California or the duration of the child’s breast-feeding. These data suggest that PBDE serum concentrations in these children resulted primarily from postnatal exposure. Conclusions: Latino children living in California have much higher PBDE serum levels than their Mexican counterparts. Given the growing evidence documenting potential health effects of PBDE exposure, the levels in young children noted in this study potentially present a major public health challenge, especially in California. In addition, as PBDEs are being phased out and replaced by other flame retardants, the health consequences of these chemical replacements should be investigated and weighed against their purported fire safety benefits. PMID:21498147

Fenster, Laura; Castorina, Rosemary; Marks, Amy R.; Sjödin, Andreas; Rosas, Lisa Goldman; Holland, Nina; Guerra, Armando Garcia; Lopez-Carillo, Lizbeth; Bradman, Asa

2011-01-01

345

Spectrophotometric assay for total peroxyl radical-trapping antioxidant potential in human serum.  

PubMed

Antioxidants prevent modification of low density lipoprotein (LDL) by free radicals and possibly also atheroma formation. The capacity of human serum to resist attacks by free radicals is measured by the total peroxyl radical-trapping potential (TRAP). Its measurement has thus far required equipment not available in many clinical laboratories such as a thermostated oxygen electrode cell or a luminometer. To develop a simpler method we used a free radical probe, dichlorofluorescin-diacetate (DCFH-DA), described before in studies of respiratory burst in inflammatory cells. Its oxidation by radicals from thermal decomposition of 2,2'-diazobis(2-amidinopropane)dihydrochloride (AAPH) converts this compound to highly fluorescent dichlorofluorescein (DCF). The DCF also has absorbance at 504 nm thus enabling the determination of TRAP either fluorometrically or spectrophotometrically. Increasing the concentration of AAPH enables the measurement of DCF formation and its inhibition by serum samples at room temperature. The intra- and interassay coefficients of variation of this assay are 3.4% and 4.6%, respectively. The mean value for serum TRAP of healthy subjects is 1155 mumol/l (n = 38). The TRAP in human serum can be increased by adding various antioxidant substances to the assay in vitro or by dietary supplementation of healthy subjects with vitamin E in vivo (P < 0.025). An increase was also found in serum vitamin E levels (P < 0.0001) and in the length of the time human LDL is able to resist oxidation (P < 0.05). Thus the determination of TRAP by this method, which requires only commercially available chemicals, can be used for the evaluation of phenomena associated with lipid accumulation in human artery wall. PMID:9144097

Valkonen, M; Kuusi, T

1997-04-01

346

Host-finding behavior of Strongyloides stercoralis infective larvae to sodium cation, human serum, and sweat.  

PubMed

The host-finding behavior of Strongyloides stercoralis infective larvae was examined by in vitro agarose assay method. As human body fluid contains 0.85% (ca 0.15 molar) NaCl, various concentrations of sodium chloride, from 0.5M to 0.01M (7 steps), were examined. Many larvae were attracted at concentrations between 0.5 and 0.05M of sodium chloride. The concentration of 0.05M attracted the most larvae. The concentration of 0.02M of sodium chloride showed greatly reduced larval attraction compared with 0.05M. Therefore, the threshold concentration was determined as 0.05M. Then, 0.05M of chemicals were examined in a further experiment. Chloride compounds (NaCl, KCl, CaCl2, MgCl2) were investigated. These chemicals are components of human body fluids. Distilled water was used as the control in all experiments. Only sodium chloride attracted the larvae. Next, alkaline compounds were examined [NaOH, KOH, Ca(OH)2, and Mg(OH)2]. Larvae accumulated only at the NaOH site. The results suggested that the Na cation is important for larval attraction. A high pH value did not influence attraction at all. Next, human serum was tested. The human serum used was from normal serum to 1:32 diluted sera by distilled water (7 steps). Hierarchical attraction was seen according to serum concentration. Next, human sweat was collected from a limited zone of chest skin where only eccrine glands were distributed. Non-diluted sweat attracted the most larvae. Sweat might act as one of the most probable factors for infection by this skin-penetrating nematode. PMID:16438188

Koga, Masataka; Nuamtanong, Supaporn; Dekumyoy, Paron; Yoonuan, Tippayarat; Maipanich, Wanna; Rojekittikhun, Wichit; Waikagul, Jitra

2005-01-01

347

Chemical Reactions  

NSDL National Science Digital Library

We are going go over a general view of reactions to prepare us for our unit on Chemical Reactions! Have fun learning! WARNING: If you are caught looking at ANY other site, without permission, you will be sent to the ALC, and you will not participate in any other computer activities for the rest of the year. Get your worksheet and begin! Overview Take this quiz and have me come over and sign off on your worksheet when you have completed the quiz! Overview Quiz Next let's take a look at what effect the rate of a chemical reaction. Rates of Reactions Another quiz, another check off by me! Rates of Reactions Quiz Now how do we measure how fast a ...

Mrs. Hicken

2009-05-04

348

Chemical warfare  

PubMed Central

Leaf-cutting ants are well known for their highly complex social organization, which provides them with a strong defense against parasites invading their colonies. Besides this attribute, these insects have morphological, physiological and structural characteristics further reinforcing the defense of their colonies. With the discovery of symbiotic bacteria present on the integument of leaf-cutting ants, a new line of defense was proposed and considered to be specific for the control of a specialized fungal parasite of the ants’ fungus gardens (Escovopsis). However, recent studies have questioned the specificity of the integumental bacteria, as they were also found to inhibit a range of fungi, including entomopathogens. The microbiota associated with the leaf-cutting ant gardens has also been proposed as another level of chemical defense, protecting the garden from parasite invasion. Here we review the chemical defense weaponry deployed by leaf-cutting ants against parasites of their fungus gardens and of the ants themselves. PMID:23795235

Samuels, Richard Ian; Mattoso, Thalles Cardoso; Moreira, Denise D.O.

2013-01-01

349

Effects of serum, its protein and lipid extracts, and commercial serum proteins and lipid on the isolated frog heart.  

PubMed

This study investigates the inotropic effects of serum, its protein and lipid extracts, and commercial serum proteins and lipid on the isolated, spontaneously-beating heart and superfused, hypodynamic ventricle of the frog. Serum taken from either man, horse, calf, frog, or rabbit evoked marked positive inotropic responses which were unaffected by cholinergic, serotonergic, and adrenergic receptor antagonists. Dialysed serum (dialisand) and void volume fractions from Sephadex G200-120 columns corresponding to large molecular weight constituents evoked marked positive inotropic responses. When serum was separated into fractions containing either proteins or lipids/lipoproteins by high-density ultracentrifugation or activated charcoal, both extracts evoked marked positive inotropic responses. Commercial serum globulins and serum containing a high proportion of immunoglobulins elicited large increases in contractile force, whereas serum albumin evoked a negative inotropic effect. Serum which was either boiled and/or treated with chymotrypsin to denature proteins also caused a marked increase in isometric twitch tension in the frog heart. Similar inotropic response was obtained with fractions of boiled serum eluted on columns of Sephadex G200-120. These fractions corresponded to molecular weight in the region of 60-70 kDa. However, the inotropic effect of boiled serum was abolished following pretreatment with lipase. Superfusion of frog hearts with commercial cardiolipin resulted in marked dose-dependent increases in contractile force. The results demonstrate the presence of at least two large molecular weight cardioactive principles in serum. These substances are comparable in size to constituents of serum proteins (e.g., globulins and immunoglobulins) and serum lipids/lipoproteins (e.g., cardiolipin) and may serve as physiological regulators of cardiac function. PMID:1939740

Singh, J; Hutton, T; Hussain, M; Waring, J J

1991-01-01

350

Serum transferrin receptor: a quantitative measure of tissue iron deficiency.  

PubMed

This study was undertaken to evaluate the role of serum transferrin receptor measurements in the assessment of iron status. Repeated phlebotomies were performed in 14 normal volunteer subjects to obtain varying degrees of iron deficiency. Serial measurements of serum iron, total iron-binding capacity, mean cell volume (MCV), free erythrocyte protoporphyrin (FEP), red cell mean index, serum ferritin, and serum transferrin receptor were performed throughout the phlebotomy program. There was no change in receptor levels during the phase of storage iron depletion. When the serum ferritin level reached subnormal values there was an increase in serum receptor levels, which continued throughout the phlebotomy program. Functional iron deficiency was defined as a reduction in body iron beyond the point of depleted iron stores. The serum receptor level was a more sensitive and reliable guide to the degree of functional iron deficiency than either the FEP or MCV. Our studies indicate that the serum receptor measurement is of particular value in identifying mild iron deficiency of recent onset. The iron status of a population can be fully assessed by using serum ferritin as a measure of iron stores, serum receptor as a measure of mild tissue iron deficiency, and hemoglobin concentration as a measure of advanced iron deficiency. PMID:2331526

Skikne, B S; Flowers, C H; Cook, J D

1990-05-01

351

Molecular Sex Differences in Human Serum  

PubMed Central

Background Sex is an important factor in the prevalence, incidence, progression, and response to treatment of many medical conditions, including autoimmune and cardiovascular diseases and psychiatric conditions. Identification of molecular differences between typical males and females can provide a valuable basis for exploring conditions differentially affected by sex. Methodology/Principal Findings Using multiplexed immunoassays, we analyzed 174 serum molecules in 9 independent cohorts of typical individuals, comprising 196 males and 196 females. Sex differences in analyte levels were quantified using a meta-analysis approach and put into biological context using k-means to generate clusters of analytes with distinct biological functions. Natural sex differences were established in these analyte groups and these were applied to illustrate sexually dimorphic analyte expression in a cohort of 22 males and 22 females with Asperger syndrome. Reproducible sex differences were found in the levels of 77 analytes in serum of typical controls, and these comprised clusters of molecules enriched with distinct biological functions. Analytes involved in fatty acid oxidation/hormone regulation, immune cell growth and activation, and cell death were found at higher levels in females, and analytes involved in immune cell chemotaxis and other indistinct functions were higher in males. Comparison of these naturally occurring sex differences against a cohort of people with Asperger syndrome indicated that a cluster of analytes that had functions related to fatty acid oxidation/hormone regulation was associated with sex and the occurrence of this condition. Conclusions/Significance Sex-specific molecular differences were detected in serum of typical controls and these were reproducible across independent cohorts. This study extends current knowledge of sex differences in biological functions involved in metabolism and immune function. Deviations from typical sex differences were found in a cluster of molecules in Asperger syndrome. These findings illustrate the importance of investigating the influence of sex on medical conditions. PMID:23251558

Ramsey, Jordan M.; Schwarz, Emanuel; Guest, Paul C.; van Beveren, Nico J. M.; Leweke, F. Markus; Rothermundt, Matthias; Bogerts, Bernhard; Steiner, Johann; Ruta, Liliana; Baron-Cohen, Simon; Bahn, Sabine

2012-01-01

352

Measurement of Staphylococcal Enterotoxin B in Serum and Culture Supernatant with a Capture Enzyme-Linked Immunosorbent Assay?  

PubMed Central

Staphylococcal enterotoxin B (SEB) is a select agent because it is a potent mitogen that elicits life-threatening polyclonal T-cell proliferation and cytokine production at very low concentrations. Efforts are in progress to develop therapeutic reagents and vaccines that neutralize or prevent the devastating effects of this toxin. Because of its rapid binding to in vivo receptors, this toxin is difficult to detect in serum. This rapid binding also constitutes a major challenge for the development of effective therapeutic reagents that can neutralize the effects of the toxin in vivo. We have developed a highly sensitive capture enzyme-linked immunosorbent assay that detects SEB in body fluids at very low levels. With this assay, the peak levels of SEB in serum and renal clearance can be measured in mice. After either oral ingestion or nasal inhalation of SEB by mice, this assay documents the transcytosis of SEB across the mucosal membranes into serum within 2 h. Furthermore, this assay was used to compare the SEB levels in different murine models for SEB-induced lethal shock and demonstrated that the coadministration of toxin-enhancing chemicals, such as d-galactosamine and lipopolysaccharide, can alter the peak serum SEB levels. Hence, this assay is a potentially useful tool for the study of the pharmacokinetics of SEB and the effects of potential therapeutic reagents on serum SEB levels. PMID:17634506

Cook, E.; Wang, X.; Robiou, N.; Fries, B. C.

2007-01-01

353

PPAR involvement in PFAA developmental toxicity  

EPA Science Inventory

Perfluoroalkyl acids (PFAAs) are found in the environment and in serum of wildlife and humans. Perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorooctane sulfonate (PFOS) are developmentally toxic in rodents. The effects of in utero exposure include increas...

354

Polyfluorinated chemicals in a spatially and temporally integrated food web in the Western Arctic.  

PubMed

This study reports on an investigation of the presence of polyfluorinated chemicals in a spatially and temporally integrated set of biological samples representing an Arctic food web. Zooplankton, Arctic cod, and seal tissues from the western Canadian Arctic were analyzed for perfluoroalkyl sulfonates [PFAS], perfluorocarboxylates [PFCAs], and other polyfluorinated acids. Perfluorooctane sulfonate [PFOS] was found in all samples [0.20-34 ng/g] and in the highest concentrations. PFCAs from nine to 12 carbons were quantified in most of the samples [0.28-6.9 ng/g]. PFCAs with carbon chain lengths of eight or less were not detected. Likewise, 8-2 fluorotelomer acid [8-2 FTA] and 8-2 fluorotelomer unsaturated acid [8-2 FTUA], products of fluorotelomer environmental transformation, were not detected. 2H,2H,3H,3H, heptadecafluoro decanoic acid [7-3 Acid], an additional metabolite from fluorotelomer biological transformation, was detected only in seal liver tissue [0.5-2.5 ng/g]. The ratios of branched to linear PFOS isomers in fish and seal tissue were not similar and did not match that of technical PFOS as manufactured. No branched PFCA isomers were detected in any samples. It is concluded that differing pharmacokinetics complicate the use of branched to linear ratios of PFCAs in attributing their presence to a specific manufacturing process. A statistical analysis of the data revealed significant correlations between PFOS and the PFCAs detected as well as among the PFCAs themselves. The 7-3 Acid was not correlated with either PFCAs or PFAS, which suggests that it may have a different exposure pathway. PMID:17698166

Powley, Charles R; George, Stephen W; Russell, Mark H; Hoke, Robert A; Buck, Robert C

2008-01-01

355

Serum lipoprotein lipids after gemfibrozil treatment.  

PubMed

The changes of serum lipoprotein lipids including the phospholipids of twelve hyperlipoproteinemic patients were studied after a four weeks treatment with 1200 mg/day gemfibrozil. There was a decrease of all VLDL lipids as well as of LDL and HDL triglycerides and an increase of HDL cholesterol. The phospholipids were influenced in different directions, particularly their concentration in the HDL was constant. The LDL/HDL lipid ratios remained elevated after gemfibrozil. To evaluate the effect of a hypolipidemic drug in more detail, the analysis of the complete lipoprotein lipid moiety and the ratios within and between the lipoproteins would be helpful. PMID:231950

Schwandt, P; Weisweiler, P; Neureuther, G

1979-02-01

356

[Determination of light chains in serum].  

PubMed

Free light chains of the immunoglobulin are identical to the Bence Jones protein. In 2001, a commercially available assay for the measurement of free light chains in serum (sFLC) became available (FreeLite Free Kappa & Free Lambda assay). Evidence from the use of the sFLC analysis is rapidly building, and the analysis is a potentially powerful supplement to the diagnostic tools already used in the diagnosis and monitoring of patients with monoclonal plasma cell disorders. However, there are several unsolved aspects for the use of this analysis which must be considered before sFLC can be used optimally in a daily clinical setting. PMID:20727297

Hansen, Charlotte Toftmann; Nielsen, Lars; Münster, Anna-Marie; Abildgaard, Niels

2010-08-23

357

Exploring the Glycosylation of Serum CA125  

PubMed Central

Ovarian cancer is the most lethal gynaecologic cancer affecting women. The most widely used biomarker for ovarian cancer, CA125, lacks sensitivity and specificity. Here, we explored differences in glycosylation of CA125 between serum from patients with ovarian cancer and healthy controls. We found differences between CA125 N-glycans from patient sera compared to controls. These include increases in core-fucosylated bi-antennary monosialylated glycans, as well as decreases in mostly bisecting bi-antennary and non-fucosylated glycans in patients compared to controls. Measurement of the glycosylated state of CA125 may therefore provide a more specific biomarker for patients with ovarian cancer. PMID:23896595

Saldova, Radka; Struwe, Weston B.; Wynne, Kieran; Elia, Giuliano; Duffy, Michael J.; Rudd, Pauline M.

2013-01-01

358

Serum albumin in 2D: a Langmuir monolayer approach.  

PubMed

Understanding of protein interaction at the molecular level raises certain difficulties which is the reason a model membrane system such as the Langmuir monolayer technique was developed. Ubiquitous proteins such as serum albumin comprise 50% of human blood plasma protein content and are involved in many biological functions. The important nature of this class of protein demands that it be studied in detail while modifying the experimental conditions in two dimensions to observe it in all types of environments. While different from bulk colloidal solution work, the two dimensional approach allows for the observation of the interaction between molecules and subphase at the air-water interface. Compiled in this review are studies which highlight the characterization of this protein using various surroundings and also observing the types of interactions it would have when at the biomembrane interface. Free-energy changes between molecules, packing status of the bulk analyte at the interface as well as phase transitions as the monolayer forms a more organized or aggregated state are just some of the characteristics which are observed through the Langmuir technique. This unique methodology demonstrates the chemical behavior and physical behavior of this protein at the phase boundary throughout the compression of the monolayer. PMID:24267981

Crawford, Nicholas F; Leblanc, Roger M

2014-05-01

359

Thermodynamic analysis of hydration in human serum heme-albumin  

SciTech Connect

Ferric human serum heme-albumin (heme-HSA) shows a peculiar nuclear magnetic relaxation dispersion (NMRD) behavior that allows to investigate structural and functional properties. Here, we report a thermodynamic analysis of NMRD profiles of heme-HSA between 20 and 60 {sup o}C to characterize its hydration. NMRD profiles, all showing two Lorentzian dispersions at 0.3 and 60 MHz, were analyzed in terms of modulation of the zero field splitting tensor for the S = {sup 5}/{sub 2} manifold. Values of correlation times for tensor fluctuation ({tau}{sub v}) and chemical exchange of water molecules ({tau}{sub M}) show the expected temperature dependence, with activation enthalpies of -1.94 and -2.46 {+-} 0.2 kJ mol{sup -1}, respectively. The cluster of water molecules located in the close proximity of the heme is progressively reduced in size by increasing the temperature, with {Delta}H = 68 {+-} 28 kJ mol{sup -1} and {Delta}S = 200 {+-} 80 J mol{sup -1} K{sup -1}. These results highlight the role of the water solvent in heme-HSA structure-function relationships.

Baroni, Simona [Invento S.r.l., 'Companies Incubator' of the University of Torino, Via Nizza 52, I-10126, Torino (Italy)] [Invento S.r.l., 'Companies Incubator' of the University of Torino, Via Nizza 52, I-10126, Torino (Italy); Pariani, Giorgio; Fanali, Gabriella [Department of Structural and Functional Biology, and Center of Neurosciences, University of Insubria, Via Alberto da Giussano 12, I-21052 Busto Arsizio (Italy)] [Department of Structural and Functional Biology, and Center of Neurosciences, University of Insubria, Via Alberto da Giussano 12, I-21052 Busto Arsizio (Italy); Longo, Dario [Department of Chemistry I.F.M. and Center of Molecular Imaging (CIM), University of Torino, Via Nizza 52, I-10126 Torino (Italy)] [Department of Chemistry I.F.M. and Center of Molecular Imaging (CIM), University of Torino, Via Nizza 52, I-10126 Torino (Italy); Ascenzi, Paolo [Department of Biology and Interdepartmental Laboratory for Electron Microscopy, Viale Guglielmo Marconi 446, University 'Roma Tre', I-00146 Roma (Italy)] [Department of Biology and Interdepartmental Laboratory for Electron Microscopy, Viale Guglielmo Marconi 446, University 'Roma Tre', I-00146 Roma (Italy); Aime, Silvio [Department of Chemistry I.F.M. and Center of Molecular Imaging (CIM), University of Torino, Via Nizza 52, I-10126 Torino (Italy)] [Department of Chemistry I.F.M. and Center of Molecular Imaging (CIM), University of Torino, Via Nizza 52, I-10126 Torino (Italy); Fasano, Mauro, E-mail: mauro.fasano@uninsubria.it [Department of Structural and Functional Biology, and Center of Neurosciences, University of Insubria, Via Alberto da Giussano 12, I-21052 Busto Arsizio (Italy)] [Department of Structural and Functional Biology, and Center of Neurosciences, University of Insubria, Via Alberto da Giussano 12, I-21052 Busto Arsizio (Italy)

2009-07-31

360

Effect of Weight Loss on Serum Osteocalcin and Its Association with Serum Adipokines  

PubMed Central

Studies have suggested that osteocalcin, a bone formation marker, is related to body metabolism and insulin sensitivity. Whether this relation is mediated through an interaction with adipokines remains unclear. The aim of this study was to assess the effect of weight loss on serum osteocalcin and its relation with three adipokines, adiponectin, chemerin, and resistin. Forty-nine obese nondiabetic males completed a four-month dietary program. Body mass index (BMI) decreased significantly from 39.7 ± 7.6 to 37.8 ± 7.6 (P < 0.001). This was associated with significant reduction in waist circumference, fasting blood glucose, HOMA-IR, total and LDL-cholesterol, bone-specific alkaline phosphatase (BAP), and resistin (P < 0.05). There was significant increase in serum adiponectin and undercarboxylated osteocalcin (uOC) (P < 0.001). The changes in uOC levels were negatively correlated with changes in serum triglycerides (r = ?0.51, P < 0.001) and positively correlated with changes in BAP (r = 0.52, P < 0.001). In contrast, the changes in uOC were not correlated with changes in BMI, waist circumference, fasting blood glucose, HOMA-IR, total and LDL-cholesterol, hsCRP, vitamin D, and circulating adipokines. We concluded that the increase in serum uOC following weight loss is not related to the changes in circulating adipokines levels. PMID:25784935

Albadah, Mohammed S.; Shaik, Shaffi Ahamed; Alsaif, Mohammed A.; Shogair, Mustafa; Nawaz, Shahid; Alfadda, Assim A.

2015-01-01

361

Human Serum Amyloid P Component is a Single Uncomplexed Pentamer in Whole Serum  

Microsoft Academic Search

Background: Serum amyloid P component (SAP) is a universal constituent of amyloid deposits and con- tributes to their pathogenesis. SAP also has important normal functions in the handling of chromatin in vivo and resistance to bacterial infection. The atomic reso- lution crystal structure of SAP is known, but its phys- iological oligomeric assembly remains controversial. In the absence of calcium,

Winston L. Hutchinson; Erhard Hohenester

2000-01-01

362

Effect of weight loss on serum osteocalcin and its association with serum adipokines.  

PubMed

Studies have suggested that osteocalcin, a bone formation marker, is related to body metabolism and insulin sensitivity. Whether this relation is mediated through an interaction with adipokines remains unclear. The aim of this study was to assess the effect of weight loss on serum osteocalcin and its relation with three adipokines, adiponectin, chemerin, and resistin. Forty-nine obese nondiabetic males completed a four-month dietary program. Body mass index (BMI) decreased significantly from 39.7 ± 7.6 to 37.8 ± 7.6 (P < 0.001). This was associated with significant reduction in waist circumference, fasting blood glucose, HOMA-IR, total and LDL-cholesterol, bone-specific alkaline phosphatase (BAP), and resistin (P < 0.05). There was significant increase in serum adiponectin and undercarboxylated osteocalcin (uOC) (P < 0.001). The changes in uOC levels were negatively correlated with changes in serum triglycerides (r = -0.51, P < 0.001) and positively correlated with changes in BAP (r = 0.52, P < 0.001). In contrast, the changes in uOC were not correlated with changes in BMI, waist circumference, fasting blood glucose, HOMA-IR, total and LDL-cholesterol, hsCRP, vitamin D, and circulating adipokines. We concluded that the increase in serum uOC following weight loss is not related to the changes in circulating adipokines levels. PMID:25784935

Albadah, Mohammed S; Dekhil, Hafedh; Shaik, Shaffi Ahamed; Alsaif, Mohammed A; Shogair, Mustafa; Nawaz, Shahid; Alfadda, Assim A

2015-01-01

363

Chemical Separations  

NSDL National Science Digital Library

This site contains complete notes in a PowerPoint-like presentation for a chemical separations course. It covers a wide variety of topics, including distillation, extraction, gas chromatography, liquid chromatograpy, chromatography theory, instrumentation, electrophoresis, field flow fractionation, and affinity chromatography. It covers these topics thoroughly using a clear, consistent, and simple presentation style. Links to major topics like GC, LC, and electrophoresis provide specific information about the theory, instrumentation, and practice related to these techniques. The site also contains many annimations illustrating important separation processes.

364

Serum levels of interleukin 6 in patients with lung cancer.  

PubMed Central

Serum interleukin 6 (IL-6) levels were measured in 75 patients with lung cancer and in 20 patients with benign lung diseases. IL-6 was detectable in 29 patients with lung cancer (39%), but was not detectable in any of the patients with benign lung diseases. Serum C-reactive protein levels and plasma fibrinogen levels were significantly higher and serum albumin concentration was significantly lower in lung cancer patients with detectable serum IL-6 levels than in those without detectable serum IL-6 levels and in patients with benign lung diseases. On the other hand, no significant difference was observed in blood platelet counts in these three groups. Moreover, serum IL-6 levels were not significantly different in lung cancer patients with or without clinically demonstrated distant metastasis. These results suggest that IL-6 may be a mediator of various reactions including an inflammatory response in lung cancer patients. PMID:7734307

Yanagawa, H.; Sone, S.; Takahashi, Y.; Haku, T.; Yano, S.; Shinohara, T.; Ogura, T.

1995-01-01

365

Serum transferrin receptor as an index of iron absorption.  

PubMed

Recent studies indicate that serum transferrin receptor levels are a quantitative index of tissue receptor mass. To determine whether the latter plays a role in the regulation of iron absorption, we examined the relationship between serum receptor, serum ferritin and iron absorption in healthy subjects. Using radioisotopic techniques we measured absorption of inorganic iron in 174 subjects and dietary nonhaem iron in 60 subjects. With both forms of iron, the correlation with absorption was far lower for serum receptor than for serum ferritin and was no longer significant when subjects with depleted iron stores were excluded. These results indicate that in normal subjects the iron store is the main physiological determinant of iron absorption and that in the absence of iron deficiency, tissue receptor mass, reflected by serum transferrin receptor levels, has no discernible influence. PMID:2207011

Cook, J D; Dassenko, S; Skikne, B S

1990-08-01

366

Organophosphorus Flame Retardants Inhibit Specific Liver Carboxylesterases and Cause Serum Hypertriglyceridemia  

PubMed Central

Humans are prevalently exposed to organophosphorus flame retardants (OPFRs) contained in consumer products and electronics, though their toxicological effects and mechanisms remain poorly understood. We show here that OPFRs inhibit specific liver carboxylesterases (Ces) and cause altered hepatic lipid metabolism. Ablation of the OPFR target Ces1g has been previously linked to dyslipidemia in mice. Consistent with OPFR inhibition of Ces1g, we also observe OPFR-induced serum hypertriglyceridemia in mice. Our findings suggest novel toxicities that may arise from OPFR exposure and highlight the utility of chemoproteomic and metabolomic platforms in the toxicological characterization of environmental chemicals. PMID:24597639

2015-01-01

367

THE COLLOIDAL BEHAVIOR OF SERUM GLOBULIN.  

PubMed

1. The globulin prepared from ox serum by dilution and precipitation with carbon dioxide has been found, by electrometric titration experiments, to behave like an amphoteric electrolyte, reacting stoichiometrically with acids and bases. 2. The potential difference developed between a solution of globulin chloride, phosphate, or acetate and a solution of the corresponding acid, free from protein, separated from the globulin by a collodion membrane, was found to be influenced by hydrogen ion concentration and salt concentration in the way predicted by Donnan's theory of membrane equilibrium. In experiments with sodium globulinate and sodium hydroxide it was found that the potential difference could be similarly explained. 3. The osmotic pressure of such solutions could be qualitatively accounted for by the Donnan theory, but exhibited a discrepancy which is explicable by analogy with certain experiments of Loeb on gelatin. 4. The application of Loeb's theory of colloidal behavior, which had previously been found to hold in the case of gelatin, casein, egg albumin, and edestin, has thus been extended to another protein, serum globulin. PMID:19871977

Hitchcock, D I

1922-09-20

368

Serum Oxidant\\/Antioxidant Status in Patients with Behçet's Disease  

Microsoft Academic Search

The aims of this study were to assess whether the increased oxidative stress in affected tissues is reflected by serum lipid peroxidation and to check for alterations in serum levels of extracellular antioxidants and antioxidant enzyme activities in patients with Behçet's disease (BD). Serum malondialdehyde (MDA) and ceruloplasmin (Cp) levels and CuZn-superoxide dismutase (CuZn-SOD) and glutathione peroxidase (GSH-Px) activities were

Seyithan Taysi; Ibrahim Kocer; Ramazan Memisogullari; Ahmet Kiziltunc

2002-01-01

369

Association of serum lipids and obesity with cardiovascular mortality  

Microsoft Academic Search

Serum lipid concentrations, relative body weight, and smoking habits were assessed in a cohort of 1648 middle-aged Finnish men who were subsequently followed for seven years. Multivariate analysis showed that serum triglyceride and cholesterol concentrations and smoking were all independently associated with cardiovascular mortality. High serum triglyceride concentrations increased the risk of cardiovascular death only when they exceeded 1.7 mmol\\/l

R Pelkonen; E A Nikkilä; S Koskinen; K Penttinen; S Sarna

1977-01-01

370

Serum leptin concentration varies with meal size and feeding frequency  

E-print Network

serum from 71 horses of various ages and body condition scores (BCS). These findings were similar to those in humans: older horses and those with higher body condition scores tended to have higher serum leptin concentrations. Interestingly..., stallions and geldings had higher serum leptin than mares, which is contrary to other species. This study emphasizes the fact that leptin concentrations are highly variable even among individuals with the same BCS, and because of this, BCS is not very...

Bruce, Samantha Michelle

2004-11-15

371

Survival of avian strains of Pasteurella multocida in chicken serum  

Microsoft Academic Search

The ability of bacteria to survive in serum is considered a likely virulence determinant in diseases where the infective bacteria become septicaemic. Optimal conditions were established to test the survival of Pasteurella multocida in chicken serum. Serum was used at 90%, the inoculum was 103–104cfu in phosphate buffered saline pH 7.4. Survival was measured after incubation for 2–4h; if survival

Ibrahim S. Diallo; Alan J. Frost

2000-01-01

372

Elevated serum zinc levels in metal fume fever  

SciTech Connect

Metal fume fever is not an uncommon syndrome among welders following exposure to oxidized metal fumes (usually zinc). The relationship of serum zinc level to the acute phase of this illness is not known. Two cases of metal fume fever, associated with elevated serum zinc levels, are presented. Further studies are necessary to determine the diagnostic usefulness of serum zinc levels in metal fume fever.

Noel, N.E.; Ruthman, J.C.

1988-11-01

373

Farm Animal Serum Proteomics and Impact on Human Health  

PubMed Central

Due to the incompleteness of animal genome sequencing, the analysis and characterization of serum proteomes of most farm animals are still in their infancy, compared to the already well-documented human serum proteome. This review focuses on the implications of the farm animal serum proteomics in order to identify novel biomarkers for animal welfare, early diagnosis, prognosis and monitoring of infectious disease treatment, and develop new vaccines, aiming at determining the reciprocal benefits for humans and animals. PMID:25257521

Girolamo, Francesco Di; D’Amato, Alfonsina; Lante, Isabella; Signore, Fabrizio; Muraca, Marta; Putignani, Lorenza

2014-01-01

374

Investigation of unusual high serum indices for lipemia in clear serum samples on Siemens analysers Dimension  

PubMed Central

Introduction: We present our work of monitoring 202 different patients with markedly elevated serum index for lipemia whereby serum samples were clear. We tried to clarify the cause of occurrence of these indices which were detected in the years 2006–2010 on Siemens Dimension analyzers. Materials and methods: In samples with unusual lipemia index we measured the concentration of lipids (total cholesterol, triglycerides, HDL and LDL cholesterol, Lp(a), ApoA1, ApoB), total proteins and checked for possible interferents (rheumatoid factor, immunoglobulins). We performed serum protein and immuno- electrophoresis. We investigated the repeatability of unusual lipemia indices during the day and after different time periods and we compared them on four different analyzers (RXL Max, Vista, Hitachi 911 and former Olympus AU640). Results: In 87% of 202 samples we found a monoclonal or biclonal peak in serum protein electrophoresis. Different types of paraproteins were confirmed with immunofixation electrophoresis. In the remaining 13%, polyclonal elevated concentrations of immunoglobulins were measured. Other parameters had no influence on appearing of these indices. The repeatability of indices was good during the first day of measurements (P values > 0.05) and markedly lower in the next days or after 3 and 12 months (P values < 0.05). The indices were elevated only on Dimension analyzers, but not on Hitachi and former Olympus analysers. Conclusion: A markedly elevated lipemia index in a clear serum sample measured on Siemens analyzers Dimension indicates a high possibility for the presence of a paraprotein in the sample. PMID:23092066

Fliser, Eva; Jerkovi?, Ksenija; Vidovi?, Tanja; Gorenjak, Maksimiljan

2012-01-01

375

Interaction of Serum microRNAs and Serum Folate With the Susceptibility to Pancreatic Cancer  

PubMed Central

Objectives The aim of this study was to investigate whether 6 candidate serum miRNAs and their interactions with serum folate level were associated with the risk for pancreatic cancer (PC). Method A hospital-based case-control study including 74 incident PC cases and 74 controls was conducted. Serum folate and miRNAs were determined by radioimmunoassay and real-time quantitative polymerase chain reaction, respectively. Cell lines AsPC-1 and PANC-1 were used for in vitro study. Results MiR-16 was elevated (P = 0.030–0.043) and miR-103 was reduced (P = 0.018–0.020) in PC after adjustment for age, sex, and smoking; however, after additional adjustment for folate, only miR-103 was significantly different between cases and controls (P = 0.010). After converting the relative expression of miRNAs into binary variables and adjusting for age, sex, smoking, and folate, the subjects with low miR-103 or low miR-601 were observed to have a higher risk for PC, with odds ratios of 2.33 (95% confidence interval, 1.06–5.10) and 2.37 (95% confidence interval, 1.07–5.26), respectively. Multifactor dimensionality reduction analysis showed a significant interaction for miR-16, folate, and smoking (cross-validation consistency, 10/10; mean testing accuracy, 0.696; P = 0.013). Interaction between miR-16 and folate was also verified in the AsPC-1 cells. Conclusion Serum miR-103; miR-601; and interactions among serum miR-16, folate, and smoking are associated with PC. PMID:25084000

Tian, Yao; Xue, Yibo; Ruan, Gechong; Cheng, Kailiang; Tian, Jing; Qiu, Qian; Xiao, Min; Li, Hui; Yang, Hong; Wang, Li

2015-01-01

376

Dyslipidemia and serum mineral profiles in patients with thyroid disorders  

PubMed Central

Objectives: To investigate changes in serum lipid profile, levels of serum minerals associated with thyroid disorders, and to compare these with the serum lipid and mineral profiles in hypothyroid patients receiving thyroxine therapy. Methods: A cross-sectional study was conducted in King Khaled Hospital, Hail, Saudi Arabia. The patient database was searched for new patients with thyroid dysfunction between January 2011 and June 2012. They were classified into 5 groups: 1) subclinical-hypothyroid (SHY), 2) overt-hypothyroid (OHY), 3) subclinical-hyperthyroid (SHE), 4) overt-hyperthyroid (OHE), 5) patients under thyroxine therapy (EU), and normal controls. Results: The OHY group showed impaired renal function; whereas, the kidney function of the SHE, OHE, and EU groups was normal. The OHY and OHE groups exhibited elevated serum glucose. The OHY group showed elevated serum cholesterol, triglyceride, and low-density lipoprotein cholesterol, and decreased high-density lipoprotein cholesterol. Serum lipids were reduced in the OHE group, and no different in the EU group compared with controls. The serum calcium and phosphate were reduced in the OHY group, whereas, in the OHE group, the phosphate was increased while magnesium and potassium were reduced. Conclusion: Hypothyroidism caused impaired renal function, glucose intolerance, hyperlipidemia, and reduction in serum phosphate. Hyperthyroidism caused a reduction in serum lipids, magnesium, and potassium. Thyroxine therapy normalized the deranged lipids and minerals, but not glucose. Results indicate that thyroid function tests should be considered when diagnosing those metabolic disorders. PMID:25491211

Abdel-Gayoum, Abdelgayoum A.

2014-01-01

377

Effect of amiodarone on serum quinidine and procainamide levels.  

PubMed

Serum levels of quinidine or procainamide were measured in patients who had amiodarone added to their antiarrhythmic regimen. Dosages of quinidine or procainamide were held constant. Eleven of 11 patients had an increase in the serum quinidine level, and 11 of 12 other patients had an increase in the serum procainamide level. The dose requirement to maintain a stable plasma level of quinidine or procainamide decreased by 37% and 20%, respectively. Clinical toxicity occasionally occurred with the increase in serum levels of quinidine and procainamide, and the dose of these drugs should be decreased when amiodarone is administered concurrently. PMID:6711425

Saal, A K; Werner, J A; Greene, H L; Sears, G K; Graham, E L

1984-05-01

378

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

Microsoft Academic Search

We describe a sensitive and specific method for measur- ing cotinine in serum by HPLC coupled to an atmo- spheric pressure chemical ionization tandem mass spec- trometer. 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 nonsmok- ers potentially exposed to environmental

John T. Bernert; Wayman E. Turner; James L. Pirkle; Connie S. Sosnoff; James R. Akins; Mary K. Waldrep; Qinghong Ann; Thomas R. Covey; Wanda E. Whitfield; Elaine W. Gunter; Barbara B. Miller; Donald G. Patterson; Larry L. Needham; W. Harry; Eric J. Sampson

379

Gonadal histology and serum vitellogenin levels of bigeye tuna Thunnus obesus from the Northern Pacific Ocean––absence of endocrine disruption bio-indicators  

Microsoft Academic Search

Endocrine disrupting chemicals such as organochlorines have been detected in a large number of marine fish. Histological observation of the gonads, measurement of serum vitellogenin (VTG) level and of liver polychlorinated biphenyl (PCB) content were performed to evaluate the reproductive health and the contamination with endocrine disruptors in bigeye tuna Thunnus obesus, collected in the northern Pacific Ocean in 1999

Shinya Hashimoto; Ryo Kurihara; Carlos Augusto Strüssmann; Tsugiko Yamasaki; Kiyoshi Soyano; Akihiko Hara; Hiroaki Shiraishi; Masatoshi Morita

2003-01-01

380

Lipophilic chemical exposure as a cause of cardiovascular disease  

PubMed Central

Environmental chemical exposure has been linked to numerous diseases in humans. These diseases include cancers; neurological and neurodegenerative diseases; metabolic disorders including type 2 diabetes, metabolic syndrome and obesity; reproductive and developmental disorders; and endocrine disorders. Many studies have associated the link between exposures to environmental chemicals and cardiovascular disease (CVD). These chemicals include persistent organic pollutants (POPs); the plastic exudates bisphenol A and phthalates; low molecular weight hydrocarbons (LMWHCs); and poly nuclear aromatic hydrocarbons (PAHs). Here it is reported that though the chemicals reported on differ widely in chemical properties and known points of attack in humans, a common link exists between them. All are lipophilic species that are found in serum. Environmentally induced CVD is related to total lipophilic chemical load in the blood. Lipophiles serve to promote the absorption of otherwise not absorbed toxic hydrophilic species that promote CVD. PMID:24179429

2013-01-01

381

Development and characterization of a canine oral mucosa equivalent in a serum-free environment.  

PubMed

The objectives of this study were to develop a serum-free system for culturing canine oral keratinocytes, the construction and characterization of a canine ex vivo produced oral mucosa equivalent (EVPOME), and transduction green fluorescent protein (GFP) into keratinocytes as a post-grafting tracking marker. Dissociated canine buccal mucosa keratinocytes were cultured in a chemically defined serum-free medium, Epilife trade mark. First-passage keratinocytes were transfected with the GFP gene using a lentiviral vector, sorted by flow cytometer and seeded onto a dermal equivalent, AlloDerm(R) to form EVPOMEs. The EVPOME was characterized by histology and immunohistochemistry, for p63, Ki-67, and involucrin. Laser confocal microscopy was used to locate GFP-transfected keratinocytes within the EVPOME. Cultured canine oral keratinocytes grew rapidly over the first three passages and then the proliferative rate decreased. The canine EVPOME formed a well-stratified epithelial layer. The majority of p63 and Ki-67 immunopositive cells were located in the basal layer whereas cytoplasmic involucrin expression was seen in the suprabasal layers, similar to native canine buccal mucosa. Under laser confocal microscopy, significant green fluorescence was observed throughout the EVPOME. In conclusion, canine EVPOMEs were successfully fabricated in a defined serum-free system with similar characteristics to native buccal mucosa. GFP-transfected canine oral keratinocytes could be identified within the EVPOME. PMID:15368264

Song, Junhui; Izumi, Kenji; Lanigan, Thomas; Feinberg, Stephen E

2004-10-01

382

Serum Phthalate Levels and Time to Pregnancy in Couples from Greenland, Poland and Ukraine  

PubMed Central

Phthalates are ubiquitous industrial chemicals that have been associated with altered reproductive function in rodents. Several human studies have reported an inverse association between male testosterone and phthalate levels. Our aim was to investigate time to pregnancy (TTP) according to serum levels of diethylhexyl phthalate (DEHP) and diisononyl phthalate (DiNP) metabolites in both partners. In 2002-2004 we enrolled 938 pregnant women and 401 male spouses from Greenland, Poland and Ukraine. Six oxidized metabolites of DEHP and DiNP were summarized for each of the two parent compounds to provide proxies of the internal exposure. We used Cox discrete-time models to estimate fecundability ratios (FR) and 95% confidence intervals (95% CIs) for men and women according to their proxy-DEHP or -DiNP serum levels adjusted for a fixed set of covariates. The FR was slightly elevated among women with high levels of DEHP (FR=1.14, 95% CI 1.00;1.30) suggesting a shorter TTP in these women. The FR was unrelated to DiNP in women, whereas the results for men were inconsistent pointing in opposite directions. First-time pregnant women from Greenland with high serum DiNP levels had a longer TTP. This study spanning large contrast in environmental exposure does not indicate adverse effects of phthalates on couple fecundity. The shorter TTP in women with high levels of DEHP metabolites is unexplained and needs further investigation. PMID:25786246

Specht, Ina Olmer; Bonde, Jens Peter; Toft, Gunnar; Lindh, Christian H.; Jönsson, Bo A. G.; Jřrgensen, Kristian T.

2015-01-01

383

Serum phthalate levels and time to pregnancy in couples from greenland, poland and ukraine.  

PubMed

Phthalates are ubiquitous industrial chemicals that have been associated with altered reproductive function in rodents. Several human studies have reported an inverse association between male testosterone and phthalate levels. Our aim was to investigate time to pregnancy (TTP) according to serum levels of diethylhexyl phthalate (DEHP) and diisononyl phthalate (DiNP) metabolites in both partners. In 2002-2004 we enrolled 938 pregnant women and 401 male spouses from Greenland, Poland and Ukraine. Six oxidized metabolites of DEHP and DiNP were summarized for each of the two parent compounds to provide proxies of the internal exposure. We used Cox discrete-time models to estimate fecundability ratios (FR) and 95% confidence intervals (95% CIs) for men and women according to their proxy-DEHP or -DiNP serum levels adjusted for a fixed set of covariates. The FR was slightly elevated among women with high levels of DEHP (FR=1.14, 95% CI 1.00;1.30) suggesting a shorter TTP in these women. The FR was unrelated to DiNP in women, whereas the results for men were inconsistent pointing in opposite directions. First-time pregnant women from Greenland with high serum DiNP levels had a longer TTP. This study spanning large contrast in environmental exposure does not indicate adverse effects of phthalates on couple fecundity. The shorter TTP in women with high levels of DEHP metabolites is unexplained and needs further investigation. PMID:25786246

Specht, Ina Olmer; Bonde, Jens Peter; Toft, Gunnar; Lindh, Christian H; Jönsson, Bo A G; Jřrgensen, Kristian T

2015-01-01

384

Serum Fibronectin Levels in Acute and Chronic Viral Hepatitis Patients  

PubMed Central

Background: The aim of this study was to investigate the serum fibronectin (FN) levels and liver enzyme activities in patients with acute hepatitis (A, B, C) and chronic viral hepatitis (B, C); determine whether the virus types correlated with disease severity; and assess whether FN could be used as a marker of virus type or disease severity in patients. Methods: A total of 60 subjects were enrolled in the study, including 20 patients with acute hepatitis (A, B, C), 20 with chronic hepatitis (B, C), and 20 healthy controls. Serum fibronectin (FN), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), and albumin were measured in all patients from blood samples. Results: Serum FN levels were significantly lower in acute (122.9 ?g/mL (SD 43.1), P < 0.001) and chronic hepatitis patients (135.7 ?g/mL (SD 46.0), P < 0 .001) compared to controls 221.4 ?g/mL (SD 32.5). A negative correlation was found between serum FN and AST (r2 = 0.528, P < 0.001), ALT (r2 = 0.425, P < 0.001), and GGT (r2 = 0.339, P < 0.001). Additionally, high serum GGT levels (? = –0.375, P = 0.010), and low serum albumin levels (? = –0.305, P = 0.008) were associated with low serum FN levels. Conclusion: Serum FN levels were lower in both acute and chronic hepatitis patients, and an inverse relationship between serum FN and serum AST, ALT, and GGT levels was found. A decrease in serum FN levels may indicate hepatitis severity as AST and ALT represent hepatocyte damage. PMID:24639609

ERTURK, Ayse; CURE, Erkan; OZKURT, Zulal; PARLAK, Emine; CURE, Medine Cumhur

2014-01-01

385

Survival of avian strains of Pasteurella multocida in chicken serum.  

PubMed

The ability of bacteria to survive in serum is considered a likely virulence determinant in diseases where the infective bacteria become septicaemic. Optimal conditions were established to test the survival of Pasteurella multocida in chicken serum. Serum was used at 90%, the inoculum was 10(3)-10(4)cfu in phosphate buffered saline pH 7.4. Survival was measured after incubation for 2-4 h; if survival was <50% the strain was considered serum susceptible. Susceptible strains were either killed or their growth was inhibited. Some resistant strains not only survived but grew rapidly in unheated serum. Thirty-five strains, all originally isolated from clinical fowl cholera, were tested; eight were susceptible, of which three were killed and five inhibited, and the remainder (27) were resistant. Ten serum-resistant P. multocida serogroup A strains were grown in hyaluronidase to remove the capsule and survival in chicken serum was re-tested. Three strains became susceptible, while seven strains remained resistant. Three serum susceptible strains were then tested in the presence of cytidine monophosphate-N-acetylneuraminic acid (CMP-NANA). This substance is present in the human serum, and is known to mask the effect of complement on Neisseria gonorrhoeae rendering susceptible strains resistant. Two of the three serum susceptible strains became resistant in the presence of CMP-NANA. Serum susceptibility/resistance was more complex than that of Escherichia coli, and the role of resistance to avian complement in the pathogenesis of fowl cholera remains to be determined. PMID:10699511

Diallo, I S; Frost, A J

2000-03-01

386

Chemical Accelerators The phrase "chemical accelerators"  

E-print Network

that there is a wealth of important chemistry occurring only at higher energies (of the order of the strength of chemicalMeetings Chemical Accelerators The phrase "chemical accelerators" is scarcely older than for one or two dozen people grew to include nearly a hundred. Chemical accelerators is a name sug- gested

Zare, Richard N.

387

Polymerized soluble venom--human serum albumin  

SciTech Connect

Extensive previous studies have demonstrated that attempts to produce polymers of Hymenoptera venoms for human immunotherapy resulted in insoluble precipitates that could be injected with safety but with very limited immunogenicity in allergic patients. We now report soluble polymers prepared by conjugating bee venom with human serum albumin with glutaraldehyde. The bee venom-albumin polymer (BVAP) preparation was fractionated on Sephacryl S-300 to have a molecular weight range higher than catalase. /sup 125/I-labeled bee venom phospholipase A was almost completely incorporated into BVAP. Rabbit antibody responses to bee venom and bee venom phospholipase A were induced by BVAP. Human antisera against bee venom were absorbed by BVAP. No new antigenic determinants on BVAP were present as evidenced by absorption of antisera against BVAP by bee venom and albumin. BVAP has potential immunotherapeutic value in patients with anaphylactic sensitivity to bee venom.

Patterson, R.; Suszko, I.M.; Grammer, L.C.

1985-03-01

388

Human pregnancy serum inhibits interleukin-2 production.  

PubMed Central

Cell-mediated immunity may be depressed during pregnancy. We used the two way mixed lymphocyte reaction as an in vitro model of cell mediated immunity and studied the effect of pregnancy sera on this system by the amount of tritiated thymidine taken up by activated lymphocytes. We found that: (1) pregnancy sera contain a factor inhibiting the mixed lymphocyte reaction; (2) the inhibition of the mixed lymphocyte reaction induced by sera could be reversed by the addition of the supernatant from allogeneic mixed lymphocyte reaction; (3) pure interleukin-1 could not reverse the inhibitory effect and (4) recombinant interleukin-2 (IL-2) completely reversed the inhibitory effect of pregnancy sera on the mixed lymphocyte reaction. We conclude that a factor (or factors) present in serum from pregnant women is capable of inhibiting the generation of IL-2 during lymphocyte activation. PMID:6239719

Nicholas, N S; Panayi, G S; Nouri, A M

1984-01-01

389

Serum antithrombin in coronary-artery disease.  

PubMed

Serum antithrombin activity (AA) was correlated with coronary angiographic findings in 69 patients with documented angina. There was excellent correlation between normal values and normal coronary circulation or only one-vessel stenosis in 30 of 35 patients (86%). When AA was above 90%, 90% of patients (20 of 22) had normal circulation or one-vessel occlusion. In 24 patients AA values were significantly decreased. Coronary angiography in this group revealed three with normal circulation or only one-vessel involvement (10%); 21 of 24 had two or three vessels occluded (90%). The correlation between severe CAD and low AA is probably coincidental to a "triggered" or "turned-on" clotting system. The most practical clinical contribution of AA estimation relates to this capacity to identify angina patients in whom clot-preventive measures (aspirin; dipyridamole; anticoagulants) might prove beneficial. PMID:55072

Innerfield, I; Goldfischer, J D; Reicher-Reiss, H; Greenberg, J

1976-01-01

390

Alterations in the rat serum proteome induced by prepubertal exposure to bisphenol a and genistein.  

PubMed

Humans are exposed to an array of chemicals via the food, drink and air, including a significant number that can mimic endogenous hormones. One such chemical is Bisphenol A (BPA), a synthetic chemical that has been shown to cause developmental alterations and to predispose for mammary cancer in rodent models. In contrast, the phytochemical genistein has been reported to suppress chemically induced mammary cancer in rodents, and Asians ingesting a diet high in soy containing genistein have lower incidence of breast and prostate cancers. In this study, we sought to: (1) identify protein biomarkers of susceptibility from blood sera of rats exposed prepubertally to BPA or genistein using Isobaric Tandem Mass Tags quantitative mass spectrometry (TMT-MS) combined with MudPIT technology and, (2) explore the relevance of these proteins to carcinogenesis. Prepubertal exposures to BPA and genistein resulted in altered expression of 63 and 28 proteins in rat sera at postnatal day (PND) 21, and of 9 and 18 proteins in sera at PND35, respectively. This study demonstrates the value of using quantitative proteomic techniques to explore the effect of chemical exposure on the rat serum proteome and its potential for unraveling cellular targets altered by BPA and genistein involved in carcinogenesis. PMID:24552547

Betancourt, Angela; Mobley, James A; Wang, Jun; Jenkins, Sarah; Chen, Dongquan; Kojima, Kyoko; Russo, Jose; Lamartiniere, Coral A

2014-03-01

391

Alterations in the Rat Serum Proteome Induced by Prepubertal Exposure to Bisphenol A and Genistein  

PubMed Central

Humans are exposed to an array of chemicals via the food, drink and air, including a significant number that can mimic endogenous hormones. One such chemical is Bisphenol A (BPA), a synthetic chemical that has been shown to cause developmental alterations and to predispose for mammary cancer in rodent models. In contrast, the phytochemical genistein has been reported to suppress chemically induced mammary cancer in rodents, and Asians ingesting a diet high in soy containing genistein have lower incidence of breast and prostate cancers. In this study, we sought to: (1) identify protein biomarkers of susceptibility from blood sera of rats exposed prepubertally to BPA or genistein using Isobaric Tandem Mass Tags quantitative mass spectrometry (TMT-MS) combined with MudPIT technology and, (2) explore the relevance of these proteins to carcinogenesis. Prepubertal exposures to BPA and genistein resulted in altered expression of 63 and 28 proteins in rat sera at postnatal day (PND) 21, and of 9 and 18 proteins in sera at PND35, respectively. This study demonstrates the value of using quantitative proteomic techniques to explore the effect of chemical exposure on the rat serum proteome and its potential for unraveling cellular targets altered by BPA and genistein involved in carcinogenesis. PMID:24552547

2015-01-01

392

Proteomic Identification of Monoclonal Antibodies from Serum  

PubMed Central

Characterizing the in vivo dynamics of the polyclonal antibody repertoire in serum, such as that which might arise in response to stimulation with an antigen, is difficult due to the presence of many highly similar immunoglobulin proteins, each specified by distinct B lymphocytes. These challenges have precluded the use of conventional mass spectrometry for antibody identification based on peptide mass spectral matches to a genomic reference database. Recently, progress has been made using bottom-up analysis of serum antibodies by nanoflow liquid chromatography/high-resolution tandem mass spectrometry combined with a sample-specific antibody sequence database generated by high-throughput sequencing of individual B cell immunoglobulin variable domains (V genes). Here, we describe how intrinsic features of antibody primary structure, most notably the interspersed segments of variable and conserved amino acid sequences, generate recurring patterns in the corresponding peptide mass spectra of V gene peptides, greatly complicating the assignment of correct sequences to mass spectral data. We show that the standard method of decoy-based error modeling fails to account for the error introduced by these highly similar sequences, leading to a significant underestimation of the false discovery rate. Because of these effects, antibody-derived peptide mass spectra require increased stringency in their interpretation. The use of filters based on the mean precursor ion mass accuracy of peptide-spectrum matches is shown to be particularly effective in distinguishing between “true” and “false” identifications. These findings highlight important caveats associated with the use of standard database search and error-modeling methods with nonstandard data sets and custom sequence databases. PMID:24684310

2015-01-01

393

Inheritance of Low Serum Immunoglobulin D  

PubMed Central

Previous studies have shown that log IgD levels in normal individuals are distributed in a nonunimodal manner. Therefore, in this study we tested whether inheritance might play a role in determination of IgD levels. IgD levels were measured in serum or plasma from 301 randomly selected children aged 6-18 yr, 245 consecutive adult blood donors, and 134 first-degree relatives of subjects with low IgD levels. Comparison of serum and plasma from five individuals revealed no difference, so the two were used interchangeably. The distributions of log IgD levels in randomly selected populations of both adults and children were nonunimodal with nadirs at 2.15 IU/ml. In both of these randomly selected populations, 13-14% of the subjects had low IgD values (<2.15 IU/ml). In addition, there was a significant sibling-sibling correlation of log IgD values (r = 0.56, n = 72, P <0.01). Because of the nonunimodality of the frequency distribution histogram for IgD values and because of the familial aggregation of these values, the study was extended to include first-degree relatives of subjects with low plasma IgD. Blood samples from 92% of living first-degree relatives, 134 individuals, were analyzed for their level of IgD, and the results of segregation and pedigree analyses of these data were compatible with autosomal recessive inheritance of an allele for low plasma IgD levels. IgD values in plasma from siblings of probands for low IgD were also non-unimodal in distribution with a nadir at ?2.15 IU/ml. The results suggest that there is autosomal recessive inheritance of an allele for low plasma IgD. PMID:678327

Dunnette, Sandra L.; Gleich, Gerald J.; Weinshilboum, Richard M.

1978-01-01

394

Antioxidant flavonoids bind human serum albumin  

NASA Astrophysics Data System (ADS)

Human serum albumin (HSA) is a principal extracellular protein with a high concentration in blood plasma and carrier for many drugs to different molecular targets. Flavonoids are powerful antioxidants and prevent DNA damage. The antioxidative protections are related to their binding modes to DNA duplex and complexation with free radicals in vivo. However, flavonoids are known to inhibit the activities of several enzymes such as calcium phospholipid-dependent protein kinase, tyrosine protein kinase from rat lung, phosphorylase kinase, phosphatidylinositol 3-kinase and DNA topoisomerases that exhibit the importance of flavonoid-protein interaction. This study was designed to examine the interaction of human serum albumin (HSA) with quercetin (que), kaempferol (kae) and delphinidin (del) in aqueous solution at physiological conditions, using constant protein concentration of 0.25 mM (final) and various drug contents of 1 ?M-1 mM. FTIR and UV-vis spectroscopic methods were used to determine the polyphenolic binding mode, the binding constant and the effects of flavonoid complexation on protein secondary structure. The spectroscopic results showed that flavonoids are located along the polypeptide chains through H-bonding interactions with overall affinity constant of Kque = 1.4 × 10 4 M -1, Kkae = 2.6 × 10 5 M -1 and Kdel = 4.71 × 10 5 M -1. The protein secondary structure showed no alterations at low pigment concentration (1 ?M), whereas at high flavonoid content (1 mM), major reduction of ?-helix from 55% (free HSA) to 42-46% and increase of ?-sheet from 15% (free HSA) to 17-19% and ?-anti from 7% (free HSA) to 10-20% occurred in the flavonoid-HSA adducts. The major reduction of HSA ?-helix is indicative of a partial protein unfolding upon flavonoid interaction.

Kanakis, C. D.; Tarantilis, P. A.; Polissiou, M. G.; Diamantoglou, S.; Tajmir-Riahi, H. A.

2006-10-01

395

Comparison of Serum Bisphenol A Concentrations in Mice Exposed to Bisphenol A through the Diet versus Oral Bolus Exposure  

PubMed Central

Background: Bisphenol A (BPA) is a widely produced endocrine-disrupting chemical. Diet is a primary route of exposure, but internal exposure (serum concentrations) in animals and humans has been measured only after single oral bolus administration. Objective: We compared serum concentrations of BPA over a 24-hr period after oral bolus administration or ad libitum feeding in mice and assessed for buildup with dietary exposure. Methods: Adult female mice were administered [dimethyl-d6]-BPA (BPA-d6) as a single oral bolus (20 mg/kg body weight) or fed a diet containing 100 mg BPA-d6/kg feed weight ad libitum for 1 week. Serum concentrations were analyzed using isotope dilution liquid chromatography coupled with electrospray tandem mass spectrometry and compared between exposure groups over the first 23 hr and after 7 days of dietary exposure. Results: Maximum concentration (Cmax) for BPA-d6 during the first 24 hr was reached at 1 hr and 6 hr for oral bolus and diet groups, respectively. Relative BPA-d6 bioavailability (unconjugated BPA-d6) was higher in diet-exposed mice than in the bolus group despite a relative lower absorption, a phenomenon consistent with an inhibitory effect of food on first-pass hepatic metabolism. In mice with ongoing dietary exposure, unconjugated BPA-d6 was higher on day 7 than on day 1. Conclusions: This is the first report of serum BPA concentrations in an animal model exposed to this chemical via the diet. Although bolus administration of BPA-d6 led to peak concentrations within 1 hr, Cmax for diet-exposed mice was delayed for several hours. However, bolus administration underestimates bioavailable serum BPA concentrations in animals—and presumably humans—than would result from dietary exposure. Exposure via diet is a more natural continuous exposure route than oral bolus exposure and is thus a better predictor of BPA concentrations in chronically exposed animals and humans. PMID:21642047

Sieli, Paizlee T.; Jašarevic´, Eldin; Warzak, Denise A.; Mao, Jiude; Ellersieck, Mark R.; Liao, Chunyang; Kannan, Kurunthachalam; Collet, Séverine H.; Toutain, Pierre-Louis; vom Saal, Frederick S.

2011-01-01

396

Evaluation of the assay for serum monoamine oxidase -- an index of hepatic fibrosis.  

PubMed

At present, neither the diagnostic efficiency, the analytic reliability nor the practicability of clinical chemical tests for estimation of the degree and/or activity of the fibrotic transformation of the chronically injured liver are satisfactory. Among the various parameters proposed, the determination of the activity of monoamine oxidase (monoamine: O2 oxidoreductase, EC 1.4.3.4) in serum seems to be advantageous. To facilitate its routine use we studied some important practical aspects of the new colorimetric assay for the activity of monoamine oxidase in serum. The reaction proceeds linearly with time for at least two hours and with enzyme concentrations up to kU/l. The buffer composition influences markedly the function of the enzyme; in Tris-HCl buffer (pH 7.2) at 37 degree C the activity is 1.35 time higher than in phosphate buffer (pH 7.3) and the temperature correlation factors are also different for both buffer systems. 0.003 mol/l of the lathyrogenic compound beta-aminopropionitrile inhibits the activity by about 50% whereas Cu2+ up to 130 mu mol/l does not affect enzyme function. Intra- and interassay precision and characterized by a CV of 3.6 and 12%, respectively. Hemolysis and hyperbilirubinemia do not interfere significantly with the determination but in hyperlipemic sera elevated enzyme activities were noticed. During storage of serum at room temperature the catalytic function decrease by about 30%/day. Of the 26 quality control sera tested, only a few contained monoamine oxidase activity that was quantitatively (i.e. similar catalytic activity in tris phosphate buffer) similar to that in human serum, and were therefore suitable for routine precision control analysis. PMID:7205149

Gressner, A M

1980-12-01

397

A spectroscopic study of phenylbutazone and aspirin bound to serum albumin in rheumatoid diseases  

NASA Astrophysics Data System (ADS)

Interaction of phenylbutazone (PBZ) and aspirin (ASA), two drugs recommended in rheumatoid diseases (RDs), when binding to human (HSA) and bovine (BSA) serum albumins, has been studied by quenching of fluorescence and proton nuclear magnetic resonance ( 1HNMR) techniques. On the basis of spectrofluorescence measurements high affinity binding sites of PBZ and ASA on albumin as well as their interaction within the binding sites were described. A low affinity binding site has been studied by proton nuclear magnetic resonance spectroscopy. Using fluorescence spectroscopy the location of binding site in serum albumin (SA) for PBZ and ASA was found. Association constants Ka were determined for binary (i.e. PBZ-SA and ASA-SA) and ternary complexes (i.e. PBZ-[ASA]-SA and ASA-[PBZ]-SA). PBZ and ASA change the affinity of each other to the binding site in serum albumin (SA). The presence of ASA causes the increase of association constants KaI of PBZ-SA complex. Similarly, PBZ influences KaI of ASA-SA complex. This phenomenon shows that the strength of binding and the stability of the complexes increase in the presence of the second drug. The decrease of KaII values suggests that the competition between PBZ and ASA in binding to serum albumin in the second class of binding sites occurs. The analysis of 1HNMR spectral parameters i.e. changes of chemical shifts and relaxation times of the drug indicate that the presence of ASA weakens the interaction of PBZ with albumin. Similarly PBZ weakens the interaction of ASA with albumin. This conclusion points to the necessity of using a monitoring therapy owning to the possible increase of uncontrolled toxic effects.

Maci??ek-Jurczyk, M.; Su?kowska, A.; Bojko, B.; Równicka-Zubik, J.; Su?kowski, W. W.

2011-11-01

398

A Platelet-Dependent Serum Factor that Stimulates the Proliferation of Arterial Smooth Muscle Cells in Vitro  

Microsoft Academic Search

Dialyzed serum from clotted monkey blood (``blood serum'') promotes the proliferation of monkey arterial smooth muscle cells in culture, but dialyzed serum prepared from recalcified platelet-poor plasma (``plasma serum'') is much less effective. Addition of platelets and calcium to platelet-poor plasma increases the activity of plasma serum to the same level achieved with blood serum. Furthermore, addition to plasma serum

Russell Ross; John Glomset; Beverly Kariya; Laurence Harker

1974-01-01

399

Comparison of different analytical methods for assessing total antioxidant capacity of human serum  

Microsoft Academic Search

Three assays were compared for the determination of total antioxidant capacity in human serum: the oxygen radical absorbance capacity (ORAC) assay, the Randox Trolox-equivalent antioxidant capacity (Randox-TEAC) assay, and the ferric reducing ability (FRAP) assay. There was a weak but significant linear correlation between serum ORAC and serum FRAP. There was no correlation either between serum ORAC and serum TEAC

Guohua Cao; Ronald L. Prior

1998-01-01

400

Increased serum cortisol binding in chronic active hepatitis  

Microsoft Academic Search

A high serum cortisol concentration, apparently due to increased cortisol-binding globulin (CBG), was found in a patient (index case) with chronic active hepatitis (CAH). We therefore performed further studies to determine whether increased cortisol binding is generally associated with CAH. Serum samples were obtained from 15 hospitalized patients with long-term liver function test elevations but no evidence of cirrhosis, 15

Ozzie Orbach; George C. Schussler

1989-01-01

401

Microneutralization assay for swine influenza virus in swine serum  

Technology Transfer Automated Retrieval System (TEKTRAN)

The microneutralization (MN) assay is a modification of the serum virus neutralization assay and is a serological test to detect the presence of functional systemic antibodies that prevent infectivity of virus. When infectious virus is mixed with serum antibody, the virus infectivity can be "neutral...

402

A Truth Serum for Sharing Rewards Arthur Carvalho  

E-print Network

A Truth Serum for Sharing Rewards Arthur Carvalho Cheriton School of Computer Science University.11 [Artificial Intelligence]: Distributed Artificial In- telligence--Multiagent systems; J.4 [Social question that we address in this paper. Cite as: A Truth Serum for Sharing Rewards, Arthur Carvalho

Larson, Kate

403

Association of Helicobacter pylori infection with elevated serum lipids  

Microsoft Academic Search

Helicobacter pylori causes a chronic gastric infection, which has been associated with coronary heart disease. To evaluate the mechanisms of this association, we studied whether the infection affects serum lipid levels as previously shown in acute infections. We analysed the serum samples of 880 males who participated in a reindeer herders' health survey in Northern Finland in 1989. H. pylori

Aino Laurila; Aini Bloigu; Simo Nayhab; Juhani Hassi; Maija Leinonen; Pekka Saikku

404

Elevated serum free fatty acid concentrations inhibit T lymphocyte signaling  

Microsoft Academic Search

Unbound cis-unsaturated free (i.e., nonesterified) fatty acids (FFA) inhibit T lymphocyte activation in vitro and therefore may exert immuno- suppressive effects. However, in blood serum the major proportion of FFA is tightly bound to albumin, whereas unbound FFA are hardly detectable. Since serum FFA elevation occurs under pathological con- ditions like insulin resistance or cancer, which are often associated with

THOMAS M. STULNIG; MARKUS BERGER; MICHAEL RODEN; HARALD STINGL; DANIEL RAEDERSTORFF; WERNER WALDHAUSL

405

Association of Helicobacter pylori infection with elevated serum lipids  

Microsoft Academic Search

Helicobacter pylori causes a chronic gastric infection, which has been associated with coronary heart disease. To evaluate the mechanisms of this association, we studied whether the infection affects serum lipid levels as previously shown in acute infections. We analysed the serum samples of 880 males who participated in a reindeer herders’ health survey in Northern Finland in 1989. H. pylori

Aino Laurila; Aini Bloigu; Simo Näyhä; Juhani Hassi; Maija Leinonen; Pekka Saikku

1999-01-01

406

Method for the automatic determination of serum iron  

Microsoft Academic Search

A simple method is described for the automated determination of serum iron and tota iron-binding capacity, which eliminates the need to render apparatus or reagents iron-free. The method is faster than normal procedures and its accuracy is comparable with other accepted methods for the determination of serum iron.

D. S. Young; Jocelyn M. Hicks

1965-01-01

407

Serum Biological Antioxidant Potential Predicts the Prognosis of Hemodialysis Patients  

Microsoft Academic Search

Background: It is well known that oxidative stress is enhanced in patients with end-stage renal disease. However, little is known about the relationship between serum antioxidant capacity and clinical outcome in hemodialysis (HD) patients. Methods: We examined the relationship between serum biomarkers of oxidative stress and clinical outcomes including all-cause mortality, hospitalization rate and incidence of cardiovascular events in HD

Tomoko Ishii; Takayasu Ohtake; Koji Okamoto; Yasuhiro Mochida; Kunihiro Ishioka; Machiko Oka; Kyoko Maesato; Ryota Ikee; Hidekazu Moriya; Sumi Hidaka; Kent Doi; Eisei Noiri; Toshiro Fujita; Shuzo Kobayashi

2011-01-01

408

Human Transferrin Confers Serum Resistance against Bacillus anthracis*  

E-print Network

Human Transferrin Confers Serum Resistance against Bacillus anthracis* Received for publication of serum by gel filtration chromatography led to the identification of human transferrin as the inhibiting but not of hypotransferrinemic mice that only have 1% circu- lating transferrin levels. We were able to definitely assign

Nizet, Victor

409

Carbohydrate deficient serum transferrin in a new systemic hereditary syndrome  

Microsoft Academic Search

Four patients with a new, inherited, complex developmental deficiency syndrome were studied. The syndrome affects the central and peripheral nervous system, and also the retina, liver, bone, adipose tissue, and genital organs. Abnormalities of glycoproteins, glycopeptide hormones, and lipids have been found in serum from these patients, the most pronounced being increased cathodal forms of transferrin. Isoforms of serum transferrin

H Stibler; J Jaeken

1990-01-01

410

A non-transferrin-bound serum iron in idiopathic hemochromatosis  

Microsoft Academic Search

The nature of iron in the serum of patients with idiopathic hemochromatosis has been studied utilizing an isotope labeling method and results have been compared with those from normal individuals and patients with other forms of liver disease. Between 2 and 4% of a tracer dose of59Fe added to normal serum was retained by DEAE Sephadex and has been designated

R. G. Batey; P. Lai Chung Fong; S. Shamir; Sheila Sherlock

1980-01-01

411

Serum zinc and pneumonia in nursing home elderly  

Technology Transfer Automated Retrieval System (TEKTRAN)

Zinc plays an important role in immune function. The association between serum zinc and pneumonia in the elderly has not been studied. The study aim is to determine if serum zinc concentrations in nursing home elderly are associated with incidence and duration of pneumonia, total and duration of ant...

412

SIMPLIFIED METHOD FOR EXTRACTING BOUND PESTICIDES FROM AVIAN SERUM  

EPA Science Inventory

A simple solid-phase extraction (SPE) method was developed to extract organochlorine pesticides (OCs) and persistent organic pollutants (POPs) from avian serum. In this method, a 1-mL serum sample fortified with two levels of OCs or POPs was treated with 8M urea or 4M urea and 4...

413

The epidemiology of serum sex hormones in postmenopausal women  

Microsoft Academic Search

Serum sex hormones may be related to the risk of several diseases including osteoporosis, heart disease, and breast and endometrial cancer in postmenopausal women. In the current report, the authors examined the epidemiology of serum sex hormones in 176 healthy, white postmenopausal women (mean age 58 years) recruited from the metropolitan Pittsburgh, Pennsylvania, area. The data were collected during 1982-1983;

J. A. Cauley; L. H. Kuller; D. LeDonne; J. P. Gutai; J. G. Powell

1989-01-01

414

Maternal serum screening for Down's syndrome in early pregnancy  

Microsoft Academic Search

The possibility of improving the effectiveness of antenatal screening for Down's syndrome by measuring human chorionic gonadotrophin concentrations in maternal serum during the second trimester to select women for diagnostic amniocentesis was examined. The median maternal serum human chorionic gonadotrophin concentration in 77 pregnancies associated with Down's syndrome was twice the median concentration in 385 unaffected pregnancies matched for maternal

N. J. Wald; H. S. Cuckle; J. W. Densem; K. Nanchahal; P. Royston; T. Chard; J. E. Haddow; G. J. Knight; G. E. Palomaki; J. A. Canick

1988-01-01

415

Serum Iron Markers in Patients With Chronic Hepatitis C Infection  

PubMed Central

Background Patients with chronic hepatitis C (CHC) often have elevated serum iron markers, which may worsen liver injury. Objectives The aim of this study was to investigate the possible correlations between iron metabolism serum markers, HCV viral load, and liver disease severity in treatment-naive patients with chronic hepatitis C infection. Patients and Methods Eighty five patients with untreated hepatitis C chronic infection were investigated. Results Twenty one patients (24.7%) had elevated serum iron levels, and 29 subjects (34.1%) had severe liver fibrosis. Significantly elevated levels of serum iron (P < 0.05) and ferritin (P < 0.001), associated with lower levels of TIBC (P < 0.05) were detected in patients with severe fibrosis compared to no/mild fibrosis. Severe necroinflammatory activity was also significantly correlated with serum iron (P < 0.001), TIBC (P < 0.05), and ferritin levels (P < 0.001). Using multiple linear regression analysis, serum levels of ferritin and transferrin were the independent variables selected as being good predictors for advanced fibrosis and severe necroinflammatory activity. No significant correlations were detected between HCV viral load and iron markers. Conclusions This study revealed that serum iron markers (especially ferritin and transferrin) might be used as surrogate markers for both liver fibrosis and necroinflammatory activity.Patients with chronic hepatitis C (CHC) often have elevated serum iron markers, which may worsen liver injury. PMID:24348638

Vagu, Codruta; Sultana, Camelia; Ruta, Simona

2013-01-01

416

Serum transferrin receptor is a truncated form of tissue receptor.  

PubMed

Recent studies have provided immunological evidence for the existence of transferrin receptor in human serum and have revealed that its concentration is a sensitive measure of erythropoiesis and iron deficiency. The present study was undertaken to establish the molecular identity of this immunoreactive component. Purification from human serum was accomplished by immunoaffinity chromatography using, as the ligand, monoclonal antitransferrin receptor antibody. The receptor preparation contained two major components with Mr of 75,000 and 85,000, which were identified as transferrin and transferrin receptor, respectively. The physicochemical and immunochemical properties of the 85,000 serum receptor were compared with those established for intact placental transferrin receptor. The serum receptor exhibited an apparent Mr = 85,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis under non-reducing conditions, as compared with 190,000 for placental transferrin receptor. Upon reduction, the Mr of serum receptor was unaltered, whereas, the 190,000 placental receptor dimer decreased to the expected monomer value of 95,000. Amino-terminal amino acid sequence analysis revealed that residues 1-19 of serum receptor were identical to residues 101-119 of intact receptor. These findings provide physicochemical evidence for the existence of transferrin receptor in human serum, establish its molecular identity as a truncated form lacking the cytoplasmic and transmembrane domains (residues 1-100) of intact receptor, and demonstrate that it exists as a transferrin-receptor complex in serum. PMID:2229063

Shih, Y J; Baynes, R D; Hudson, B G; Flowers, C H; Skikne, B S; Cook, J D

1990-11-01

417

Serum magnesium levles in patients treated with phenytoin.  

PubMed

Phenytoin and magnesium levels were measured in eighty epileptics and seventy-one control subjects in an investigation into possible effects of phenytoin on serum magnesium levels. Phenytoin levels were measured using GLC and magnesium levels by atomic absorption spectrophotometry. The study showed no significant effect of phenytoin on serum mangesium concentration. PMID:1149293

Blyth, A; Stewart, M J

1975-07-23

418

Concentrations of main serum opsonins in early infancy  

Microsoft Academic Search

The evolution of the main serum opsonins in neonates and infants of varying gestational age was investigated to provide reference values for these opsonins in early infancy. Serum concentrations of immunoglobulins, IgG subclasses, C3, C4 and fibronectin were serially measured from birth until the age of 6 months in term and preterm infants. Measurements were performed by rate nephelometry. Five

V. Drossou; F. Kanakoudi; E. Diamanti; V. Tzimouli; T. Konstantinidis; A. Germenis; G. Kremenopoulos; V. Katsougiannopoulos

1995-01-01

419

Influence of a Diurnal Oxygen Pulse on Fish Serum Proteins  

Microsoft Academic Search

Changes in the serum protein, as shown by electrophoretic analyses, appear to be correlated with changes in the environment of the organism. These changes may be associated with aquatic pollution.A diurnal oxygen pulse of 3 ppm for 8 hours per day for 9 days produced a significant stress pattern in the serum protein fractions of bluegills and largemouth bass, but

Gerald R. Bouck; Robert C. Ball

1965-01-01

420

Use of proteomic patterns in serum to identify ovarian cancer  

Microsoft Academic Search

Background New technologies for the detection of early- stage ovarian cancer are urgently needed. Pathological changes within an organ might be reflected in proteomic patterns in serum. We developed a bioinformatics tool and used it to identify proteomic patterns in serum that distinguish neoplastic from non-neoplastic disease within the ovary. Methods Proteomic spectra were generated by mass spectroscopy (surface-enhanced laser

Emanuel F Petricoin III; Ali M Ardekani; Ben A Hitt; Peter J Levine; Vincent A Fusaro; Seth M Steinberg; Gordon B Mills; Charles Simone; David A Fishman; Elise C Kohn; Lance A Liotta

2002-01-01

421

Selected Blood Serum Elements in Van (Turkey) Cats  

Microsoft Academic Search

Altunok V., E. Yazar, N. Yuksek: Selected Blood Serum Elements in Van (Turkey) Cats. Acta Vet Brno 2007, 76: 171-177. The Turkish Van cat originates from eastern Turkey. One of the characteristic features of Van cats is the colour of their eyes, which can be both eyes blue, both eyes amber or one eye blue and the other amber. Serum

V. Altunok; E. Yazar; N. Yuksek

2007-01-01

422

A MICROTITRE SERUM NEUTRALIZATION TEST FOR BOVINE EPHEMERAL FEVER VIRUS  

Microsoft Academic Search

A simple quantitative screening test for measuring serum neutralizing antibody to bovine ephemeral fever virus has been developed using Vero cells and plastic microtitre trays. The sensitivity of the test is comparable with conventional methods and represents a considerable saving in time, equipment and reagents. This procedure differs from other similar microtitre procedures in that serum\\/virus mixtures are not incubated

GW Burgess

1974-01-01

423

Elevated serum ribonuclease in patients with pancreatic cancer.  

PubMed Central

Serum RNase (ribonuclease) of normal persons and of patients with pancreatitis, carcinoma of pancreas, or other neoplasms was determined with poly(C) as substrate. Strikingly abnormal elevations occur in the serum RNase of patients with pancreatic cancer. There is no elevation in the serum RNase level of patients with pancreatitis. Average serum RNase values of 52 normal persons, 10 patients with pancreatitis, 30 patients with pancreatic cancer, 28 patients with breast cancer, 11 patients with lung cancer, 20 patients with colon cancer, six patients with stomach cancer, and four patients with liver cancer, respectively, were 104, 120, 383, 131, 173, 197, 194, and 152 units/ml of serum. Ninety percent of the patients with pancreatic cancer were above the level of 250 units of serum and 90% of all patients with varied cancers were below this level. In the presence of severe renal insufficiency, marked elevation of serum RNase was also observed. Serum RNase, because of its unique specificity, pancreatic origin, and its abnormal elevation in sera of patients with pancreatic cancer, serves as a reliable biochemical marker of carcinoma of the pancreas in the presence of normal renal function. PMID:1065880

Reddi, K K; Holland, J F

1976-01-01

424

Serum autoantibodies, ulcerative colitis and primary sclerosing cholangitis  

Microsoft Academic Search

The aetiology of primary sclerosing cholangitis is unknown, but it is closely associated with ulcerative colitis. Serum anticolon antibodies, crossreacting with portal tracts, have been reported in patients with ulcerative colitis but no studies have been carried out in primary sclerosing cholangitis. The frequency of serum anticolon antibodies and portal tract antibodies have been measured in 24 patients with primary

R W Chapman; M Cottone; W S Selby; H A Shepherd; S Sherlock; D P Jewell

1986-01-01

425

SERUM BIOMARKERS OF AGING IN THE BROWN NORWAY RAT  

EPA Science Inventory

Serum biomarkers to identify susceptibility to disease in aged humans are well researched. On the other hand, our understanding of biomarkers in animal models of aging is limited. Hence, we applied a commercially available panel of 58 serum analytes to screen for possible biomark...

426

Rapid and precise analysis for calcium in blood serum  

NASA Technical Reports Server (NTRS)

Differential absorption spectrophotometric technique, using murexide, gives a highly precise analysis of calcium in volumes of blood serum as small as 0.01 ml. The method of additions and proper timing allows compensation to be made for fading, variation in type of serum or plasma, and aging of the specimen.

Holtzman, R. B.; Ilcewicz, F. H.

1969-01-01

427

Immunohistochemical demonstration of serum proteins in human cerebral gliomas  

Microsoft Academic Search

The leakage of different serum proteins, including immunoglobulins, into human cerebral gliomas was studied by use of the unlabeled peroxidase-antiperoxidase (PAP) method on cryostat and paraffin sections. Our series of 50 tumour biopsies included 21 isomorphic astrocytomas and oligodendrogliomas (grade II), 19 anaplastic astrocytomas and oligodendrogliomas (grade III), and 10 glioblastomas (grade IV). The immunohistochemical staining of the serum proteins

R. J. Seitz; W. Wechsler

1987-01-01

428

Interrelationship between serum lipid profile, serum hormones and other components of the metabolic syndrome  

Microsoft Academic Search

The aim of the present study was to investigate the association between the serum lipid profile and components of the metabolic\\u000a syndrome, such as central obesity (anthropometric, computed tomography and fat cell data), insulin, sex-hormonebinding-globulin\\u000a (SHBG) and different hormones influencing this important syndrome, e.g. sex steroids, leptin and tumor necrosis factor-alpha\\u000a (TNF-?). The sample consisted of 85 obese patients (30

M. Garaulet; F. Pérez-Llamas; S. Zamora; F. J. Tebar

2002-01-01

429

Measurement of organochlorine levels in postprandial serum or in blood collected in serum separator tubes.  

PubMed

Whether organochlorine blood levels in fasting and postprandial specimens provide equivalent measures of exposure and the extent to which collecting blood in tubes containing material to separate serum and blood cells corrupts the specimen are unclear. In this paper, we present data from two studies that address both of these issues. In the first study, 27 women provided fasting blood in plain, silicone-coated Vacutainer tubes (red-topped) and in similar tubes containing serum separator gel (SSTs), as well as a postprandial specimen in a red-topped tube. The specimens collected in SSTs were left to stand overnight, with the gel in contact with the sample. In the second study, the blood of 12 industrial incinerator workers was collected in red-topped tubes and in SSTs. Blood in SSTs was left in contact with the gel for 5 days. Serum organochlorine residue levels ([1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene] (DDE)) and polychlorinated biphenyls) in samples collected in red-topped tubes were highly correlated with levels measured in samples collected in SSTs (all Pearson r values were > or = 0.79). Postprandial and fasting organochlorine levels were also highly correlated (Pearson r values > or = 0.89). Our results indicate that timing of the collection of blood in relation to meals and use of SSTs to collect blood specimens did not greatly affect the relative classification of subjects with respect to serum level of DDE or polychlorinated biphenyls. The longer the specimen was in contact with the SST gel, however, the lower the level of organochlorine that was detected and, at least for DDE, the greater the misclassification caused. PMID:8877068

Longnecker, M P; Bernstein, L; Bird, C L; Yancey, A K; Peterson, J C

1996-09-01

430

SPE-HPLC purification of endocrine-disrupting compounds from human serum for assessment of xenoestrogenic activity.  

PubMed

Assessment of xenoestrogenic activity in human serum samples requires the removal of endogenous sex hormones to assure that the activity measured originates from xenobiotic compounds only. Serum samples representing high, medium and lower accumulation of persistent organic pollutants (POPs) were extracted using solid-phase extraction (SPE) followed by normal-phase high-performance liquid chromatography (NP-HPLC) for separation of POPs from endogenous hormones. The recovery of polychlorinated biphenyl (PCB) congeners in spiked serum samples was up to 86 %, making the extraction method suitable for the study. MVLN cells, stably transfected with an estrogen receptor (ER) luciferase reporter vector (estrogen response element chemically activated luciferase expression, ERE-CALUX), were exposed to the reconstituted SPE-HPLC extracts for determination of the integrated estrogenic activity. The effects of PCBs were analyzed by direct in vitro exposure of PCBs (nos. 138, 153, 180) and by ex vivo analysis of SPE-HPLC extracts from serum spiked with the PCBs. Similar effects on ER transactivation were observed for the direct in vitro and the ex vivo analysis experiments. The ER transactivation responses determined for actual serum samples were in the linear range of the dose-response curve. 17beta-Estradiol titrations showed that the xenoestrogenic effects were mediated via ER. Moreover, our SPE-HPLC-ERE-CALUX assay was demonstrated to elicit high interlaboratory correlation. In the present study the combination of SPE-HPLC purification and the ex vivo estrogenic responses measured by ERE-CALUX was validated and considered to be a valuable tool to assess the combined ER effect of lipophilic serum POPs where additive/synergistic and agonistic/antagonistic effects are integrated giving an overall estimate of exposure and bioactivity. PMID:16791568

Hjelmborg, Philip Sebastian; Ghisari, Mandana; Bonefeld-Jorgensen, Eva Cecilie

2006-07-01

431

Serum vitamin C and other biomarkers differ by genotype of phase 2 enzyme genes GSTM1 and GSTT1123  

PubMed Central

Background: Glutathione S-transferases (GSTs) detoxify environmental chemicals and are involved in oxidative stress pathways. Deletion polymorphisms affect enzyme activities and have been associated with risk of disease. Objective: The objective was to clarify whether biomarkers of oxidation, antioxidation, inflammation, and nutritional factors differ by GST genotype in healthy adults. Design: Subjects (n = 383) consisted of nonsmokers and nonusers of antiinflammatory drugs and antioxidant vitamin supplements. Deletion polymorphisms of GSTM1 and GSTT1 were genotyped. F2-isoprostanes, malondialdehyde, C-reactive protein, serum vitamin C, carotenoids, tocopherols, and other nutritional factors were assessed. Results: The concentration of serum vitamin C was higher in persons with the inactive GSTM1-0 genotype (P = 0.006). This relation was unchanged after adjustment for age, sex, BMI, or dietary vitamin C. F2-isoprostanes and malondialdehyde were lower in the GSTM1-0 and GSTT1-0 groups, respectively, but significance was lost after control for serum vitamin C. The dual deletion, GSTM1-0/GSTT1-0 (n = 37), was associated with higher serum iron and total and LDL-cholesterol concentrations (all P < 0.01) and lower malondialdehyde concentrations, which persisted after adjustment for age, sex, BMI, and serum vitamin C. Carotenoids and ?- and ?-tocopherols were not associated with either genotype. Conclusions: Oxidative stress and inflammation biomarkers differ by GST genotype, but serum vitamin C appears to be the most consistent factor. Examination of other relevant genes may be needed to understand the concentration and function of ascorbic acid in the GST enzyme system. This trial is registered at clinicaltrials.gov as NCT00079963. PMID:21813807

Shaikh, Nishat; Jensen, Christopher D; Volberg, Vitaly; Holland, Nina

2011-01-01

432

Prevalence of Elevated Serum Homocysteine and Serum Lipoprotein ‘a’ in Women  

PubMed Central

Background: Recent studies indicate that the risk of coronary artery disease (CAD) in women is no less than that in men and menopausal women are equally vulnerable as men. Studies of recent risk factors like hyperhomocysteinemia and elevation in lipoprotein (a) reveal controversial role of the same. This study hence is an attempt to study the prevalence of these factors in women and their correlation with lipid profile. Materials and Methods: Two hundred women were enrolled in the study- 100 premenopausal women (21-45y) and 100 menopausal (50-55y). All the subjects were screened for homocysteine by ELISA and lipoprotein (a) and lipid profile by automation. Results: Prevalence of hyperhomocysteinemia was 52% and 62% in premenopausal and menopausal women respectively. A significant positive correlation was seen for total cholesterol and triacylglycerol with serum Homocysteine in premenopausal women while pronounced positive correlation for serum cholesterol with serum Homocysteine in menopausal women. The prevalence of elevated lipoprotein (a) was 42% and 45% in premenopausal and menopausal women respectively. There was no correlation between lipoprotein (a) and lipid profile in both groups. Conclusion: The findings of the study conclude that premenopausal and menopausal women constitute a subpopulation where recent risk factors like hyperhomocysteinemia and elevated lipoprotein(a) could be assessed along with lipid profile as screening tests to identify the risk of CAD. This would help in proper counselling of the concerned women and minimize the risk. PMID:25478337

Tilak, Mona A; Dhat, Vaishali V; More, Umesh M; Shinde, Sarita A; Phalak, Pradnya; Deshmukh, Anita D

2014-01-01

433

Relation of Serum Leptin and Adiponectin Level to Serum C-Reactive Protein: The INTERLIPID Study  

PubMed Central

Objective. Despite considerable study, the relevance of leptin and adiponectin for atherosclerosis development is still unsettled. We investigated relations of serum leptin and adiponectin to serum C-reactive protein (CRP), using the INTERLIPID dataset on Japanese emigrants living in Hawaii and Japanese in Japan. Design and Methods. Serum leptin, adiponectin, and CRP were measured by standardized methods in men and women of ages 40 to 59 years from two population samples, one Japanese-American in Hawaii (83 men, 89 women) and the other Japanese in central Japan (111 men, 104 women). Participants with CRP >10?mg/L were excluded. Results. Sex-specific multiple linear regression analyses, with log-transformed leptin and adiponectin (log-leptin, log-adipo), site (Hawaii = 1, Japan = 0), SBP, HbA1c, smoking (cigarettes/day), and physical activity index score of the Framingham Offspring Study as covariates, showed that log-leptin directly related and log-adipo inversely related to log-CRP for both sexes (Ps < 0.05 to <0.01). Addition to the model of BMI and interaction terms (BMI × log-leptin, BMI × log-adipo, SITE × log-leptin, SITE × log-adipo) resulted in disappearance of statistical significance except for direct relation of log-leptin to log-CRP in men (P = 0.006). Conclusions. Leptin directly related to CRP independent of BMI and other confounding factors in men but not in women. PMID:24371525

Nakamura, Yasuyuki; Ueshima, Hirotsugu; Miura, Katsuyuki; Kita, Yoshikuni; Okamura, Tomonori; Okayama, Akira; Choudhury, Sohel R.; Rodriguez, Beatriz; Masaki, Kamal H.; Stamler, Jeremiah

2013-01-01

434

Spectroscopic imaging of serum proteins using quantum cascade lasers.  

PubMed

First measurements of biomedical imaging using quantum cascade lasers (QCL) are presented. We report spectroscopic imaging of serum proteins using QCLs as an example for monitoring surface biocontamination. We found that dry smears of human serum can be spectroscopically imaged, identified, and quantified with high sensitivity and specificity. The core parts of the imaging platform consist of optically multiplexing three QCLs and an uncooled microbolometer camera. We show imaging of human serum proteins at 6.1, 9.25, and 9.5 ?m QCLs with high sensitivity and specificity. The sensitivity limit of 3???g/cm˛ of the human serum spot was measured at an S/N=3.The specificity of human serum detection was measured at 99% probability at a threshold of 77???g/cm˛. We anticipate our imaging technique to be a starting point for more sophisticated biomolecular diagnostic applications. PMID:23515866

Mukherjee, Anadi; Bylund, Quentin; Prasanna, Manu; Margalit, Yotam; Tihan, Tarik

2013-03-01

435

Simultaneous liquid chromatographic determination of some tetracyclines in serum.  

PubMed

A sensitive liquid chromatographic method has been developed for the simultaneous determination of oxytetracycline, minocycline, tetracycline, and doxycycline in serum. A se