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1

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Chemical Substances; Final Significant New Use Rule AGENCY: Environmental Protection...TSCA), EPA is amending a significant new use rule (SNUR) for perfluoroalkyl sulfonate...substances that have completed the TSCA new chemical review process, but have not...

2013-10-22

2

Associations between Serum Perfluoroalkyl Acids and LINE-1 DNA Methylation  

PubMed Central

Perfluoroalkyl acids (PFAAs) are persistent, synthetic compounds that are used in a number of consumer products. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been associated with cardiovascular risk factors, and changes in gene expression and DNA methylation in animals and cellular systems. However, whether PFAA exposure is associated with LINE-1 DNA methylation, a potential marker of cardiovascular risk, in humans remains unknown. We sought to evaluate the cross-sectional associations between serum PFAAs and LINE-1 DNA methylation in a population highly exposed to PFOA. We measured serum PFAAs twice four to five years apart in 685 adult participants (47% male, mean age ± SD=42 ± 11 years). We measured percent LINE-1 DNA methylation in peripheral blood leukocytes at the second time point (follow-up), and estimated absolute differences in LINE-1 methylation associated with an interquartile (IQR) shift in mean PFAA serum levels. IQR increases in mean serum PFOA, PFOS, perfluorononanoic acid (PFNA), and perfluorohexane sulfonate (PFHxS) were associated with differences of ?0.04 (p=0.16), 0.20 (p=0.001), 0.06 (p=0.19), and 0.02 (p=0.57), respectively, in % LINE-1 methylation at follow-up after adjustment for potential confounders. We observed a monotonic increase in LINE-1 DNA methylation across tertiles of PFOS and PFNA (ptrend=0.02 for both associations), but not across tertiles of PFOA or PFHxS (ptrend=0.71 and 0.44, respectively). In summary, serum PFOS was associated with LINE-1 methylation, while serum PFOA, PFHxS, and PFNA were not. Additional research is needed to more precisely determine whether these compounds are epigenetically active. PMID:24263140

Watkins, Deborah J.; Wellenius, Gregory A.; Butler, Rondi A.; Bartell, Scott M.; Fletcher, Tony; Kelsey, Karl T.

2014-01-01

3

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

4

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

Code of Federal Regulations, 2014 CFR

...Long-chain perfluoroalkyl carboxylate chemical substances. 721.10536 Section 721...SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10536...

2014-07-01

5

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

Microsoft Academic Search

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

Rocio Monroy; Katherine Morrison; Koon Teo; Stephanie Atkinson; Cariton Kubwabo; Brian Stewart; Warren G. Foster

2008-01-01

6

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

7

Perfluoroalkyl Chemicals and Asthma among Children 12–19 Years of Age: NHANES (1999–2008)  

PubMed Central

Background: Perfluoroalkyl chemicals (PFCs) are a family of commonly used industrial chemicals whose persistence and ubiquity in human blood samples has led to concern about possible toxicity. Several animal studies and one recent human study have suggested a link between exposure to PFCs and asthma, although few epidemiologic studies have been conducted. Objectives: We investigated children’s PFC serum concentrations and their associations with asthma-related outcomes. Methods: We evaluated the association between serum concentrations of eight PFCs, including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS), with self-reported lifetime asthma, recent wheezing, and current asthma using data from participants 12–19 years of age from the 1999–2000 and 2003–2008 National Health and Nutrition Examination Surveys. Results: In multivariable-adjusted models, PFOA was associated with higher odds of ever having received a diagnosis of asthma [odds ratio (OR) = 1.18; 95% CI: 1.01, 1.39 for a doubling in PFOA], whereas for PFOS there were inverse relationships with both asthma and wheezing (OR = 0.88; 95% CI: 0.74, 1.04, and OR = 0.83; 95% CI: 0.67, 1.02, respectively). The associations were attenuated after accounting for sampling weights. No associations were seen between the other PFCs and any outcome. Conclusions: This cross-sectional study provides some evidence for associations between exposure to PFCs and asthma-related outcomes in children. The evidence is inconsistent, however, and prospective studies are needed. Citation: Humblet O, Diaz-Ramirez LG, Balmes JR, Pinney SM, Hiatt RA. 2014. Perfluoroalkyl chemicals and asthma among children 12–19 years of age: NHANES (1999–2008). Environ Health Perspect 122:1129–1133;?http://dx.doi.org/10.1289/ehp.1306606 PMID:24905661

Humblet, Olivier; Diaz-Ramirez, Ledif Grisell; Balmes, John R.; Pinney, Susan M.

2014-01-01

8

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...

9

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...

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

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

12

On the stability of perfluoroalkyl-substituted singlet carbenes: a coupled-cluster quantum chemical study.  

PubMed

A series of trifluoromethyl-substituted carbenes R-C(:)-CF3 (R = NMe2, OMe, F, PMe2, P(NMe2)2, P(N(Pr-i)2)2, SMe, Cl); (dimethylamino)(perfluoroalkyl)carbenes Me2N-C(:)-R (R = CF3, C2F5, n-C3F7, i-C3F7, and t-C4F9) and symmetrically substituted carbenes R-C(:)-R (R = NMe2, OMe, F, PMe2, SMe, Cl) have been investigated by means of quantum chemistry methods. Different levels of approximation were used, including the CCSD(T) approach also known in quantum chemistry as the "golden standard", in combination with three different basis sets (TZVP, cc-pVDZ, cc-pVTZ). Relative stabilities of carbenes have been estimated using the differences between the singlet and triplet ground state energies (?EST) and energies of the hydrogenation reaction for the singlet and triplet ground states of the carbenes. The latter seem to correlate better with stability of carbenes than the ?EST values. The (13)C NMR chemical shifts of the methylidene carbon indicate the more high-field chemical shift values in the known, isolable carbenes compared to the unstable ones. This is the first report on the expected chemical shifts in the highly unstable singlet carbenes. Using these criteria, some carbene structures from the studied series (as, for instance, Me2N-C(:)-CF3, Me2N-C(:)-C3F7-i) are proposed as good candidates for the experimental preparation. PMID:24471524

Rozhenko, Alexander B; Schoeller, Wolfgang W; Leszczynski, Jerzy

2014-02-27

13

Perfluoroalkyl acids and related chemistries Toxicokinetics and modes of action  

EPA Science Inventory

The perfluoroalkyl acid salts (both carboxylates and sulfonates, hereafter designated as PFAAs) and their derivatives are important chemicals that have numerous consumer and industrial applications. However, recent discoveries that some of these compounds have global distribution...

14

Current Understanding of Perfluoroalkyl Acid Toxicology  

EPA Science Inventory

The perfluoroalkyl acids (PFAAs) are a family of organic chemicals consisting of a perfluorinated carbon backbone (4-14 carbons in length) and an anionic head group (sulfonate, carboxylate or phosphonate). These compounds have excellent surface-tension reducing properties and hav...

15

Perfluoroalkyl acids : Recent activities and research progress  

EPA Science Inventory

The perfluoroalkyl acids (PFAAs) are a family of man-made fluorinated organic chemicals consisting of a carbon backbone typically of four to fourteen in length and a charged functional moiety (primarily carboxylate, sulfonate or phosphonate). The two most widely known PFAAs are ...

16

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

17

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

18

TOWARD A RISK ASSESSMENT OF PERFLUOROALKYL ACIDS  

EPA Science Inventory

Perfluoroalkyl acids (PFAA) such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS),and fluorotelomer alcoholsare surfactants that have wide applications in industrial and consumer products. Various fluorotelomer alcohols are known to be metabolized to perfluo...

19

Perfluoroalkyl Acids and Related Chemistries—Toxicokinetics and Modes of Action  

Microsoft Academic Search

The perfluoroalkyl acid salts (both carboxylates and sulfonates, hereafter designated as PFAAs) and their derivatives are important chemicals that have numerous consumer and industrial applications. However, recent discoveries that some of these compounds have global distribution, environmental persistence, presence in humans and wildlife, as well as toxicity in laboratory animal models, have generated considerable scientific, regulatory, and public interest on

Melvin E. Andersen; John L. Butenhoff; Shu-Ching Chang; David G. Farrar; Gerald L. Kennedy; Christopher Lau; Geary W. Olsen; Jennifer Seed; Kendall B. Wallacekj

2008-01-01

20

Perfluoroalkyl and polyfluoroalkyl substances in the environment: terminology, classification, and origins.  

PubMed

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. 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 P J

2011-10-01

21

High Lipophilicty of Perfluoroalkyl Carboxylate and Sulfonate  

PubMed Central

Here we report on remarkably high lipophilicity of perfluoroalkyl carboxylate and sulfonate. A lipophilic nature of this emerging class of organic pollutants has been hypothesized as an origin of their bioaccumulation and toxicity. Both carboxylate and sulfonate, however, are considered hydrophilic while perfluroalkyl groups are not only hydrophobic but also oleophobic. Partition coefficients of homologous series of perfluoroalkyl and alkyl carboxylates between water and n-octanol were determined as a measure of their lipophilicity by ion-transfer cyclic voltammetry. Very similar lipophilicity of perfluoroalkyl and alkyl chains with the same length is demonstrated experimentally for the first time by fragment analysis of the partition coefficients. This finding is important for pharmaceutical and biomedical applications of perfluoroalkyl compounds. Interestingly, ?2 orders of magnitude higher lipophilicity of a perfluoroalkyl carboxylate or sulfonate in comparison to its alkyl counterpart is ascribed nearly exclusively to their oxoanion groups. The higher lipophilicity originates from a strong electron-withdrawing effect of the perfluoroalkyl group on the adjacent oxoanion group, which is weakly hydrated to decrease its hydrophilicity. In fact, the inductive effect is dramatically reduced for a fluorotelomer with an ethylene spacer between perfluorohexyl and carboxylate groups, which is only as lipophilic as its alkyl counterpart, nonanoate, and is 400 times less lipophilic than perfluorononanoate. The high lipophilicity of perfluoroalkyl carboxylate and sulfonate implies that their permeation across such a thin lipophilic membrane as a bilayer lipid membrane is limited by their transfer at a membrane/water interface. The limiting permeability is lower and less dependent on their lipophilicity than the permeability controlled by their diffusion in the membrane interior as assumed in the classical solubility-diffusion model. PMID:19170492

Jing, Ping; Rodgers, Patrick J.; Amemiya, Shigeru

2009-01-01

22

Toxicokinetics of perfluoroalkyl carboxylic acids with different carbon chain lengths in mice and humans.  

PubMed

Objectives: Perfluoroalkyl carboxylic acids (PFCAs) consist of analogs with various carbon chain lengths. Their toxicokinetics have remained unexplored except in the case of perfluorooctanoic acid (8 carbon chemicals). This study aimed to investigate the toxicokinetics of PFCAs with six to fourteen carbon atoms (C6 to C14) in mice and humans. Methods: We applied a two-compartment model to mice administered PFCAs intravenously or by gavage. The time courses of the serum concentration and tissue distribution and elimination were evaluated for 24 h after treatment. For human samples, urine from healthy volunteers, bile from patients who underwent biliary drainage, and cerebral spinal fluid (CSF) from brain drainage were collected. Results: The mouse experiment showed that short-chained PFCAs (C6 and C7) were rapidly eliminated in the urine, whereas long-chain PFCAs (C8 to C14) accumulated in the liver and were excreted slowly in feces. Urinary clearance of PFCAs in humans also decreased with increasing alkyl chain lengths, while biliary clearances increased. C9 to C10 had the smallest total clearance for both mice and humans. However, disparities existed in the magnitude of the total clearance between mice and humans. A slightly higher partition ratio (brain/serum) was observed for long-chained PFCAs in mice, but this was not observed in the corresponding partition ratio in humans (CSF/serum). Conclusions: The large sequestration volumes of PFCAs in the liver seem to be attributable to the liver's large binding capacity in both species. This will be useful in evaluating PFCA bioaccumulation in other species. PMID:25422127

Fujii, Yukiko; Niisoe, Tamon; Harada, Kouji H; Uemoto, Shinji; Ogura, Yasuhiro; Takenaka, Katsunobu; Koizumi, Akio

2014-11-21

23

Physico-chemical factors influencing autologous conditioned serum purification.  

PubMed

Autologous conditioned serum (ACS) is a recent biotherapy based on certain cytokines anti-inflammatory properties mainly used for the reduction of osteoarthritis (OA) symptoms. Here we investigated different physico-chemical factors influencing ACS purification and cytokine production. Human venous blood was incubated in the presence of different diameter beads (respectively 2.5, 3, 3.5, and 4?mm) or glass beads with different types of coating (polished or coated with CrSO4). Sera were recovered, and the concentrations of pro-inflammatory and anti-inflammatory relevant cytokines were measured using Luminex(®) technology. Fresh whole blood incubated for 24?h highly increased production of interleukin (IL)-6 and IL-8 cytokines. At the same time, the concentrations of IL-1?, IL-1 receptor agonist (IL-1Ra), IL-10, and tumor necrosis factor (TNF)-? were slightly induced. The highest cytokine concentrations were obtained with the exposure of whole blood to 3-mm glass beads and 3.5-mm polished beads. The minimum IL-1?/IL-1Ra ratio obtained was 3.2±1.3 after 24-h incubation without any beads. ACS has been shown to alleviate clinical symptoms of OA in clinical studies. This descriptive study demonstrated that different pro- and anti-inflammatory cytokines are present in ACS since no selective anti-inflammatory cytokines were produced based on the different protocols. Furthermore, we showed that CrSO4-treated glass beads are not necessary and that the absence of beads combined with a 24-h incubation could also lead to an enriched serum. PMID:24570844

Magalon, Jeremy; Bausset, Olivier; Veran, Julie; Giraudo, Laurent; Serratrice, Nicolas; Magalon, Guy; Dignat-George, Françoise; Sabatier, Florence

2014-02-01

24

Level and temporal trend of perfluoroalkyl acids in Greenlandic Inuit  

PubMed Central

Objectives Perfluoroalkyl acids (PFAAs) have been detected in human blood, breast milk and umbilical cord blood across the globe. PFAAs do accumulate in the marine food chain in Arctic regions. In Greenland, increasing PFAA concentrations were observed during 1982–2006 in ringed seals and polar bears. However, until now, no data have been reported for PFAAs in Greenlandic Inuit. This study assesses the level and temporal trend of serum PFAAs in Greenlandic Inuit. Study design Cross-section and temporal time trend survey. Methods Serum PFAA levels were determined in 284 Inuit from different Greenlandic districts using liquid chromatography-tandem mass spectrometry with electrospray ionization. The temporal time trend of serum PFAAs in Nuuk Inuit during 1998–2005 and the correlation between serum PFAAs and legacy persistent organic pollutants (POPs) were explored. Results Serum PFAA levels were higher in Nuuk Inuit than in non-Nuuk Inuit. Within the same district, higher PFAA levels were observed for males. An age-dependent, increasing trend of serum PFAA levels in the period from 1998–2005 was observed for Nuuk Inuit. For the pooled gender data, no significant association between PFAAs and legacy POPs was observed for Nuuk Inuit while for non-Nuuk Inuit this correlation was significant. No correlation between PFAAs and legacy POPs was found for male Inuit, whereas significant correlation was observed both for pooled female Inuit and for non-Nuuk Inuit females. Conclusions We suggest that sources other than seafood intake might contribute to the observed higher PFAA levels in Nuuk Inuit compared to the pooled non-Nuuk Inuit.1 PMID:22456049

Long, Manhai; Bossi, Rossana; Bonefeld-Jørgensen, Eva C.

2012-01-01

25

Perfluoroalkyl Amines: A New Class of Long-Lived Greenhouse Gases?  

NASA Astrophysics Data System (ADS)

Polyfluorinated compounds have the potential to act as potent greenhouse gases, due to absorption of the carbon-fluorine bond in the atmospheric window. Perfluoroalkyl amines are a class of thermally and chemically stable compounds marketed for use in numerous applications, including electronic testing and heat transfer. To assess the potential for climate impact, the radiative efficiency and atmospheric lifetime of perfluorotributyl amine (PFBAm) were determined. PFBAm was shown to have a radiative efficiency of 0.86 W m-2 ppb-1, which is higher than any compound yet detected in the atmosphere. The lifetime of this compound is likely limited by photolysis in the mesosphere, on the timescale of 800 years. The potential for perfluoroalkyl amines to behave as greenhouse gases is only realized if they are present in the atmosphere. The perfluorotripropyl and perfluorotrihexyl amine congeners are listed as high-production chemicals, with production in the range of hundreds of tonnes between 1986 and 2002 (1). An air sampling, extraction and analysis method employing thermal desorption, cryofocusing and GC-MS with negative chemical ionization has been developed to detect perfluoroalkyl amines in the atmosphere. Results and implications of the air sampling study will be discussed. (1)Howard, P. H.; Meylan, W. "EPA Great Lakes Study for Identification of PBTs to Develop Analytical Methods: Selection of Additional PBTs - Interim Report," EPA Contract No. EP-W-04-019, 2007.

Young, C. J.; Mabury, S. A.

2008-12-01

26

Perfluoroalkyl compounds (PFCs) in wildlife from an urban estuary.  

PubMed

Previous research has documented the bioaccumulation of perfluoroalkyl compounds (PFCs) in apex predators in remote locations but few studies have evaluated urban estuaries. To assess the importance of PFCs in San Francisco Bay, two apex predators in the San Francisco Bay, double-crested cormorants (Phalacrocorax auritus) and Pacific harbor seals (Phoca vitulina richardii), were sampled. Prey fish (Atherinops affinis and Menidia audens) were also evaluated to better understand potential sources of PFCs to the foodweb. Perfluorooctane sulfonate (PFOS) was the primary PFC detected in cormorant eggs, small fish and harbor seal serum. PFOS detected in San Francisco Bay seal serum was typically an order of magnitude higher than those at the reference site. PFOS concentrations were highest in seals and cormorant eggs from the highly urbanized southern portion of the Bay. PFOS in eggs from the southern part of the Bay remained relatively constant between 2006 and 2009 despite the phase-out of perfluorosulfonyl-based compounds nationally. In addition, these levels exceed the avian predicted no effects concentration of 1.0 ?g mL(-1). Concentrations of the remaining PFCs measured were substantially lower than those of PFOS. PMID:22134832

Sedlak, Margaret D; Greig, Denise J

2012-01-01

27

Perfluoroalkyl acids: recent research highlights  

EPA Science Inventory

Perfluorinated compounds are organic chemicals in which all hydrogen molecules of the carbon-chain are substituted by fluorine molecules. Generally, there are two types of perfluorinated compounds, the perfluoroalkanes that are primarily used clinically for oxygenation and respir...

28

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

29

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

E-print Network

Raman spectroscopy Dahu Qi and Andrew J. Berger We report measurements of chemical concentrations in clinical blood serum and urine samples using liquid-core optical fiber (LCOF) Raman spectroscopy) spectroscopy, and Raman spectroscopy are all intrinsically reagentless and have been explored for chemical

Berger, Andrew J.

30

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

2014-09-19

31

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...

32

Determination of polyfluoroalkyl phosphoric acid diesters, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, perfluoroalkyl carboxylic acids, and perfluoroalkane sulfonic acids in lake trout from the Great Lakes region.  

PubMed

A comprehensive method to extract perfluoroalkyl carboxylic acids, perfluoroalkane sulfonic acids, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, and polyfluoroalkyl phosphoric acid diesters simultaneously from fish samples has been developed. The recoveries of target compounds ranged from 78 % to 121 %. The new method was used to analyze lake trout (Salvelinus namaycush) from the Great Lakes region. The results showed that the total perfluoroalkane sulfonate concentrations ranged from 0.1 to 145 ng/g (wet weight) with perfluorooctane sulfonate (PFOS) as the dominant contaminant. Concentrations in fish between lakes were in the order of Lakes Ontario ? Erie > Huron > Superior ? Nipigon. The total perfluoroalkyl carboxylic acid concentrations ranged from 0.2 to 18.2 ng/g wet weight. The aggregate mean perfluorooctanoic acid (PFOA) concentration in fish across all lakes was 0.045 ± 0.023 ng/g. Mean concentrations of PFOA were not significantly different (p > 0.1) among the five lakes. Perfluoroalkyl phosphinic acids were detected in lake trout from Lake Ontario, Lake Erie, and Lake Huron with concentration ranging from non-detect (ND) to 0.032 ng/g. Polyfluoroalkyl phosphoric acid diesters were detected only in lake trout from Lake Huron, at levels similar to perfluorooctanoic acid. PMID:22722738

Guo, Rui; Reiner, Eric J; Bhavsar, Satyendra P; Helm, Paul A; Mabury, Scott A; Braekevelt, Eric; Tittlemier, Sheryl A

2012-11-01

33

40 CFR 721.7200 - Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer.  

Code of Federal Regulations, 2010 CFR

...Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...In addition, the following human health hazard statement shall...apply to this section except as modified by this paragraph....

2010-07-01

34

40 CFR 721.7200 - Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer.  

Code of Federal Regulations, 2011 CFR

...Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...In addition, the following human health hazard statement shall...apply to this section except as modified by this paragraph....

2011-07-01

35

40 CFR 721.7200 - Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer.  

Code of Federal Regulations, 2014 CFR

...Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...In addition, the following human health hazard statement shall...apply to this section except as modified by this paragraph....

2014-07-01

36

40 CFR 721.7200 - Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer.  

Code of Federal Regulations, 2012 CFR

...Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...In addition, the following human health hazard statement shall...apply to this section except as modified by this paragraph....

2012-07-01

37

40 CFR 721.7200 - Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer.  

Code of Federal Regulations, 2013 CFR

...Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...In addition, the following human health hazard statement shall...apply to this section except as modified by this paragraph....

2013-07-01

38

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

39

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

Wielsøe, Maria; Long, Manhai; Ghisari, Mandana; Bonefeld-Jørgensen, Eva C

2014-11-12

40

Perfluoroalkyl acids and related chemistries--toxicokinetics and modes of action.  

PubMed

The perfluoroalkyl acid salts (both carboxylates and sulfonates, hereafter designated as PFAAs) and their derivatives are important chemicals that have numerous consumer and industrial applications. However, recent discoveries that some of these compounds have global distribution, environmental persistence, presence in humans and wildlife, as well as toxicity in laboratory animal models, have generated considerable scientific, regulatory, and public interest on an international scale. The Society of Toxicology Contemporary Concepts in Toxicology Symposium, entitled "Perfluoroalkyl Acids and Related Chemistries: Toxicokinetics and Modes-of-Action Workshop" was held February 14-16, 2007 at the Westin Arlington Gateway, Arlington, VA. In addition to the Society of Toxicology, this symposium was sponsored by 3M Company, DuPont, Plastics Europe, and the U.S. Environmental Protection Agency. The objectives of this 3-day meeting were to (1) provide an overview of PFAA toxicity and description of recent findings with the sulfonates, carboxylates, and telomer alcohols; (2) address the toxicokinetic profiles of various PFAAs among animal models and humans, and the biological processes that are responsible for these observations; (3) examine the possible modes of action that determine the PFAA toxicities observed in animal models, and their relevance to human health risks; and (4) identify the critical research needs and strategies to fill the existing informational gaps that hamper risk assessment of these chemicals. This report summarizes the discourse that occurred during the symposium. PMID:18003598

Andersen, Melvin E; Butenhoff, John L; Chang, Shu-Ching; Farrar, David G; Kennedy, Gerald L; Lau, Christopher; Olsen, Geary W; Seed, Jennifer; Wallace, Kendall B

2008-03-01

41

Serum lipid abnormalities in a chemical/viral mouse model for Reye's syndrome.  

PubMed

Neonatal mice given nontoxic dermal applications of an industrial surfactant, Toximul MP8 (Tox), and subsequently infected with sublethal doses of mouse-adapted human Influenza B (Lee) virus (FluB) develop many of the biochemical features of Reye's Syndrome (RS). To determine whether these also include abnormal circulating lipid, we examined serum lipid profiles in the mouse model throughout the treatment course using Iatroscan-TH10. Following 10 days of exposure to surfactant, serum phospholipid and cholesterol levels were significantly reduced relative to control animals. These reductions were transient; however, four days following virus administration, significant differences in serum lipid were again evident. These abnormalities coincided and correlated with increased animal mortality. Animals that received combined Tox + virus treatment had significant decreases in serum total lipids relative to control animals, a reflection of a reduction in all lipid classes, including phospholipid, cholesterol, neutral glycerides (triglycerides plus diglycerides) and free fatty acids. Phospholipid (specifically phosphatidylcholine and lysophosphatidylcholine) and free fatty acid levels in the Tox + virus group were also significantly lower than those in animals that received virus alone. This study has demonstrated that suckling mice given chemical/viral treatment have the serum hypopanlipidemia but not the freefattyacidemia that are characteristic of RS. PMID:3736346

Murphy, M G; Archambault-Schertzer, L; Ackman, R G; Crocker, J F

1986-06-01

42

Chemical ionization mass spectrometry of trimethylsilylated carbohydrates and organic acids retained in uremic serum.  

PubMed

After appropriate sample pretreatment and derivatization, uremic serum was investigated by combined high resolution gas chromatography and mass spectrometry, using both electron impact and chemical ionization methods. Electron impact and chemical ionization spectra of a number of identified (trimethylsilylated) carbohydrates and organic acids are compared. The utilization of chemical ionization mass spectrometry, with isobutane as the reagent gas, is discussed in detail. The influence of the reagent gas pressure on the total ion current and on the spectral appearance was studied. The identification of compounds, based on electron impact mass spectral data, was confirmed and often aided appreciably by using this technique. The chemical ionization spectra of trimethylsilyated alditols and aldonic acids, as well as of other organic acids showed protonated molecular ions, whereas aldoses did not. Differences with electron impact spectra are found mainly in the high mass region. The loss of one or more trimethylsilanol groups becomes the predominating fragmentation route at higher reagent gas pressures. PMID:534687

Schoots, A C; Leclercq, P A

1979-11-01

43

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

44

Stable but reactive perfluoroalkylzinc reagents: application in ligand-free copper-catalyzed perfluoroalkylation of aryl iodides.  

PubMed

The aromatic perfluoroalkylation catalyzed by a copper(I) salt with bis(perfluoroalkyl)zinc reagents Zn(RF)2(DMPU)2, which were prepared and then isolated as a stable white powder from perfluoroalkyl iodide and diethylzinc, was accomplished to provide the perfluoroalkylated products in good-to-excellent yields. The advantages of this reliable and practical catalytic reaction are 1) air-stable and easy-to-handle bis(perfluoroalkyl)zinc reagents can be utilized, 2) the reagent is reactive and hence the operation without activators and ligands is simple, and 3) not only trifluoromethylation but also perfluoroalkylation can be attained. PMID:25393887

Aikawa, Kohsuke; Nakamura, Yuzo; Yokota, Yuki; Toya, Wataru; Mikami, Koichi

2015-01-01

45

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...

46

Sorption behaviour of perfluoroalkyl substances in soils.  

PubMed

The sorption behaviour of three perfluoroalkyl substances (PFASs), perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutane sulfonic acid (PFBS), was studied in six soils with contrasting characteristics, especially in the organic carbon content. Sorption isotherms were obtained by equilibrating the soil samples with 0.01molL(-1) CaCl2 solutions spiked with increasing concentrations of the target PFAS. The sorption reversibility of PFASs was also tested for some of the samples. Liquid chromatography coupled to tandem mass spectrometry was used to quantify the target PFASs in the solutions. Both the Freundlich and linear models were appropriate to describe the sorption behaviour of PFASs in soils, and enabled us to derive solid-liquid distribution coefficients (Kd) for each compound in each soil. Kd values increased from 19 to 295mLg(-1) for PFOS, from 2.2 to 38mLg(-1) for PFOA and from 0.4 to 6.8mLg(-1) for PFBS, and were positively correlated with the organic carbon content of the soil. KOC values obtained from the correlations were 710, 96 and 17mLg(-1) for PFOS, PFOA and PFBS, respectively. Whereas Kd values decreased in the sequence PFOS>PFOA>PFBS, desorption yields were lower than 13% for PFOS, from 24 to 58% for PFOA, and from 32 to 60% for PFBS. This shows that the physicochemical characteristics of PFASs, basically their hydrophobicity, controlled their sorption behaviour in soils, with PFOS being the most irreversibly sorbed PFAS. PMID:25531590

Milinovic, Jelena; Lacorte, Silvia; Vidal, Miquel; Rigol, Anna

2015-04-01

47

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

48

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...

49

(Me3Si)3SiH-mediated intermolecular radical perfluoroalkylation reactions of olefins in water.  

PubMed

Perfluoroalkyl-substituted compounds are regarded as important components of fluorophors and for the introduction of fluorous tags into organic substrates. Their syntheses in organic solvents are achieved through different methods, among which, the addition of perfluoroalkyl radicals to unsaturated bonds represents a convenient choice. On the other hand, intermolecular radical reactions in water have attracted the attention of synthetic chemists as a strategic route to carbon-carbon bond formation reactions. In this paper we undertook the intermolecular addition of perfluoroalkyl radicals on electron rich alkenes and alkenes with electron withdrawing groups in water, mediated by silyl radicals, and obtained perfluoroalkyl-substituted compounds in fairly good yields. The radical triggering events employed consist of the thermal decomposition of an azo compound and the dioxygen initiation. Our results indicate that for intermolecular carbon-carbon bond formation reactions mediated by (Me(3)Si)(3)SiH, the decomposition of the azo compound 1,1'-azobis(cyclohexanecarbonitrile) (ACCN) is the best radical initiator. We also found that water exerts a relevant solvent effect on the rates of perfluoroalkyl radical additions onto double bonds and the H atom abstraction from the silane. Our account provides a versatile and convenient method to achieve perfluoroalkylation reactions of alkenes in water to render perfluoroalkylated alkanes as key intermediates in the synthesis of fluorophors and other fluorinated materials. This is the first report where perfluoroalkyl-substituted alkanes are synthesized through intermolecular radical carbon-carbon bond formation reactions in water, mediated by silyl radicals. PMID:20738111

Barata-Vallejo, Sebastián; Postigo, Al

2010-09-17

50

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 14days, 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 14days 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

51

Do Human Milk Concentrations of Persistent Organic Chemicals Really Decline During Lactation? Chemical Concentrations During Lactation and Milk/Serum Partitioning  

PubMed Central

Background Conventional wisdom regarding exposures to persistent organic chemicals via breast-feeding assumes that concentrations decline over the course of lactation and that the mother’s body burden reflects her cumulative lifetime exposure. Two important implications stemming from these lines of thought are, first, that assessments of early childhood exposures should incorporate decreasing breast milk concentrations over lactation; and, second, that there is little a breast-feeding mother can do to reduce her infant’s exposures via breast-feeding because of the cumulative nature of these chemicals. Objectives We examined rates of elimination and milk/serum partition coefficients for several groups of persistent organic chemicals. Methods We collected simultaneous milk and blood samples of 10 women at two times postpartum and additional milk samples without matching blood samples. Results Contrary to earlier research, we found that lipid-adjusted concentrations of polybrominated diphenyl ethers, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and furans, and organochlorine pesticides in serum and milk do not consistently decrease during lactation and can increase for some women. Published research has also suggested an approximate 1:1 milk/serum relationship (lipid adjusted) on a population basis for 2,3,7,8-tetrachlorodibenzo-p-dioxin; however, our results suggest a more complex relationship for persistent, lipophilic chemicals with the milk/serum relationship dependent on chemical class. Conclusions Decreases in concentration of lipophilic chemicals on a lipid-adjusted basis during lactation should no longer be assumed. Thus, the concept of pumping and discarding early milk as means of reducing infant exposure is not supported. The hypothesis that persistent lipophilic chemicals, on a lipid-adjusted basis, have consistent concentrations across matrices is likely too simplistic. PMID:20019916

LaKind, Judy S.; Berlin, Cheston M.; Sjödin, Andreas; Turner, Wayman; Wang, Richard Y.; Needham, Larry L.; Paul, Ian M.; Stokes, Jennifer L.; Naiman, Daniel Q.; Patterson, Donald G.

2009-01-01

52

Cellular target recognition of perfluoroalkyl acids: in vitro evaluation of inhibitory effects on lysine decarboxylase.  

PubMed

Perfluoroalkyl acids (PFAAs) have been shown to bind with hepatic peroxisome proliferator receptor ?, estrogen receptors and human serum albumin and subsequently cause some toxic effects. Lysine decarboxylase (LDC) plays an important role in cell growth and developmental processes. In this study, the inhibitory effect of 16 PFAAs, including 13 perfluorinated carboxylic acids (PFCAs) and 3 perfluorinated sulfonic acids (PFSAs), on lysine decarboxylase (LDC) activity was investigated. The inhibition constants obtained in fluorescence enzyme assays fall in the range of 2.960 ?M to 290.8 ?M for targeted PFCAs, and 41.22 ?M to 67.44 ?M for targeted PFSAs. The inhibitory effect of PFCAs increased significantly with carbon chain (7-18 carbons), whereas the short chain PFCAs (less than 7 carbons) did not show any effect. Circular dichroism results showed that PFAA binding induced significant protein secondary structural changes. Molecular docking revealed that the inhibitory effect could be rationalized well by the cleft binding mode as well as the size, substituent group and hydrophobic characteristics of the PFAAs. At non-cytotoxic concentrations, three selected PFAAs inhibited LDC activity in HepG2 cells, and subsequently resulted in the decreased cadaverine level in the exposed cells, suggesting that LDC may be a possible target of PFAAs for their in vivo toxic effects. PMID:25093300

Wang, Sufang; Lv, Qiyan; Yang, Yu; Guo, Liang-Hong; Wan, Bin; Zhao, Lixia

2014-10-15

53

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

54

Chemical structure of the arabinogalactan protein from gum ghatti and its interaction with bovine serum albumin.  

PubMed

Exudate gums, because of their beneficial properties, have been significant items of international trade in various industries for centuries. This manuscript sets out to gain insight into the fine structural details of an arabinogalactan protein (AGP) of gum ghatti (Anogeissus latifolia gum). The presence of a highly branched 554 kDa AGP having 1,6-linked Galp, 1,2-linked Manp, 1,3-linked Araf and 1,4-linked GlcpA main chain, substituted at O-4,6 of 1,2-linked Manp, and O-3/O-3,4 of 1,6-linked Galp residues by Araf, Arap and Galp units was revealed by chemical, chromatographic, ESMS, and NMR analyses. In particular, ESMS analysis of per acetylated oligomeric fragments derived from AGP by Smith degradation followed by acetylation was described as a commanding tool for providing critical structural information on a spectrum of glycerol tagged oligosaccharides. In addition, formation of an electrostatically driven complex between the isolated AGP and bovine serum albumin resulting in changes in the microenvironment around the tryptophan residues of BSA was established. A moderate radical scavenging activity comparable with those of standard antioxidants was observed from the AGP fraction (?94% at 1 mg/mL) that could be valuable in foods or pharmaceutical products as alternatives to synthetic antioxidants. PMID:25498648

Ghosh, Kanika; Ray, Sayani; Ghosh, Debjani; Ray, Bimalendu

2015-03-01

55

Mass Spectra of Some Perfluoroalkyl and Perfluoroalkylether Substituted 1,2,4-Oxadiazoles  

NASA Technical Reports Server (NTRS)

Electron impact fragmentation patterns were obtained for 1,4-bis[(5-perfluoro-n-heptyl)-1,2,4-oxadiazolyl- benzene, its perfluoroalkylether substituted analogue, 3,5-bis(perfluoroalkyl)-, 3,5-bis(perfluoroalkylether)- and 3-perfluoroalkylether-5-perfluoroalkyl-1,2,4-oxadiazoles. In the compounds containing the phenylene group the molecular ion constituted the base peak; the main process was the breakdown of the oxadiazole ring with concurrent liberation of the perfluoroalkyl or perfluoroalkylether nitrile molecule; cleavage of the fluorinated chain ot to the oxadiazole ring was found to take place to a considerable degree. In the perfluorinated 1,2,4-oxadiazoles cleavage beta to the oxadiazole ring occurred preferentially; fragmentation of the ring itself took place to a limited degree only. The 3-perfluoroalkylether-5-perfluoroalkyl-1,2,4-oxadiazole appeared to undergo the primary beta-cleavage exclusively at the perfluoroalkylether sidechain.

Paciorek, Kazimiera J. L.; Nakahara, James H.; Kratzer, Reinhold H.; Rosser, Robert W.

1977-01-01

56

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....

57

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

58

Partitioning Solvophobic and Dispersion Forces in Alkyl and Perfluoroalkyl Cohesion.  

PubMed

Fluorocarbons often have distinct miscibility properties compared to their nonfluorinated analogues. These differences may be attributed to van der Waals dispersion forces or solvophobic effects, but their contributions are notoriously difficult to separate in molecular recognition processes. Here, molecular torsion balances were used to compare cohesive alkyl and perfluoroalkyl interactions in a range of solvents. A simple linear regression enabled the energetic partitioning of solvophobic and van der Waals forces in the self-association of apolar chains. The contributions of dispersion interactions in apolar cohesion were found to be strongly attenuated in solution compared to the gas phase, but still play a major role in fluorous and organic solvents. In contrast, solvophobic effects were found to be dominant in driving the association of apolar chains in aqueous solution. The results are expected to assist the computational modelling of van der Waals forces in solution. PMID:25413159

Adam, Catherine; Yang, Lixu; Cockroft, Scott L

2014-11-20

59

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

60

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

61

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

62

High lipophilicity of perfluoroalkyl carboxylate and sulfonate: implications for their membrane permeability.  

PubMed

Here we report on remarkably high lipophilicity of perfluoroalkyl carboxylate and sulfonate. A lipophilic nature of this emerging class of organic pollutants has been hypothesized as an origin of their bioaccumulation and toxicity. Both carboxylate and sulfonate, however, are considered hydrophilic while perfluroalkyl groups are not only hydrophobic but also oleophobic. Partition coefficients of a homologous series of perfluoroalkyl and alkyl carboxylates between water and n-octanol were determined as a measure of their lipophilicity by ion-transfer cyclic voltammetry. Very similar lipophilicity of perfluoroalkyl and alkyl chains with the same length is demonstrated experimentally for the first time by fragment analysis of the partition coefficients. This finding is important for pharmaceutical and biomedical applications of perfluoroalkyl compounds. Interestingly, approximately 2 orders of magnitude higher lipophilicity of a perfluoroalkyl carboxylate or sulfonate in comparison to its alkyl counterpart is ascribed nearly exclusively to their oxoanion groups. The higher lipophilicity originates from a strong electron-withdrawing effect of the perfluoroalkyl group on the adjacent oxoanion group, which is weakly hydrated to decrease its hydrophilicity. In fact, the inductive effect is dramatically reduced for a fluorotelomer with an ethylene spacer between perfluorohexyl and carboxylate groups, which is only as lipophilic as its alkyl counterpart, nonanoate, and is 400 times less lipophilic than perfluorononanoate. The high lipophilicity of perfluoroalkyl carboxylate and sulfonate implies that their permeation across such a thin lipophilic membrane as a bilayer lipid membrane is limited by their transfer at a membrane/water interface. The limiting permeability is lower and less dependent on their lipophilicity than the permeability controlled by their diffusion in the membrane interior as assumed in the classical solubility-diffusion model. PMID:19170492

Jing, Ping; Rodgers, Patrick J; Amemiya, Shigeru

2009-02-18

63

The impact of semiconductor, electronics and optoelectronic industries on downstream perfluorinated chemical contamination in Taiwanese rivers  

Microsoft Academic Search

This study provides the first evidence on the influence of the semiconductor and electronics industries on perfluorinated chemicals (PFCs) contamination in receiving rivers. We have quantified ten PFCs, including perfluoroalkyl sulfonates (PFASs: PFBS, PFHxS, PFOS) and perfluoroalkyl carboxylates (PFCAs: PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA) in semiconductor, electronic, and optoelectronic industrial wastewaters and their receiving water bodies (Taiwan's Keya,

Angela Yu-Chen Lin; Sri Chandana Panchangam; Chao-Chun Lo

2009-01-01

64

Serum lipid abnormalities in a chemical\\/viral mouse model for Reye's syndrome  

Microsoft Academic Search

Neonatal mice given nontoxic dermal applications of an industrial surfactant, Toximul MP8 (Tox), and subsequently infected\\u000a with sublethal doses of mouse-adapted human Influenza B (Lee) virus (FluB) develop many of the biochemical features of Reye's\\u000a Syndrome (RS). To determine whether these also include abnormal circulating lipid, we examined serum lipid profiles in the\\u000a mouse model throughout the treatment course using

M. G. Murphy; L. Archambault-Schertzer; R. G. Ackman; J. F. S. Crocker

1986-01-01

65

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

66

Chemical and cytokine features of innate immunity characterize serum and tissue profiles in inflammatory bowel disease  

PubMed Central

Inflammatory bowel disease (IBD) arises from inappropriate activation of the mucosal immune system resulting in a state of chronic inflammation with causal links to colon cancer. Helicobacter hepaticus-infected Rag2?/? mice emulate many aspects of human IBD, and our recent work using this experimental model highlights the importance of neutrophils in the pathology of colitis. To define molecular mechanisms linking colitis to the identity of disease biomarkers, we performed a translational comparison of protein expression and protein damage products in tissues of mice and human IBD patients. Analysis in inflamed mouse colons identified the neutrophil- and macrophage-derived damage products 3-chlorotyrosine (Cl-Tyr) and 3-nitrotyrosine, both of which increased with disease duration. Analysis also revealed higher Cl-Tyr levels in colon relative to serum in patients with ulcerative colitis and Crohn disease. The DNA chlorination damage product, 5-chloro-2?-deoxycytidine, was quantified in diseased human colon samples and found to be present at levels similar to those in inflamed mouse colons. Multivariate analysis of these markers, together with serum proteins and cytokines, revealed a general signature of activated innate immunity in human IBD. Signatures in ulcerative colitis sera were strongly suggestive of neutrophil activity, and those in Crohn disease and mouse sera were suggestive of both macrophage and neutrophil activity. These data point to innate immunity as a major determinant of serum and tissue profiles and provide insight into IBD disease processes. PMID:23754421

Knutson, Charles G.; Mangerich, Aswin; Zeng, Yu; Raczynski, Arkadiusz R.; Liberman, Rosa G.; Kang, Pilsoo; Ye, Wenjie; Prestwich, Erin G.; Lu, Kun; Wishnok, John S.; Korzenik, Joshua R.; Wogan, Gerald N.; Fox, James G.; Dedon, Peter C.; Tannenbaum, Steven R.

2013-01-01

67

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

68

Perfluoroalkyl acids in urban stormwater runoff: influence of land use.  

PubMed

Perfluoroalkyl acids (PFAAs) are persistent organic pollutants in the environment and have been reported to have nonpoint sources. In this study, six PFAAs with different chain lengths were monitored in stormwater runoff from seven storm events (2009-2011) at various outfall locations corresponding to different watershed land uses. We found PFAA(s) in 100% of stormwater runoff samples. Monitoring results and statistical analysis show that PFAAs in stormwater runoff from residential areas mainly came from rainfall. On the other hand, non-atmospheric sources at both industrial and commercial areas contributed PFAAs in stormwater runoff. The mass flux of PFAAs from stormwater runoff in the Twin Cities (Minneapolis and St. Paul, MN) metropolitan area is estimated to be about 7.86 kg/year. In addition, for the first time, we monitored PFAAs on the particles/debris in stormwater runoff and found high-level PFOS on the particulate matter in runoff collected from both industrial and commercial areas; the levels were so high that the finding could not be explained by the solid-water partitioning or adsorption. PFOS on the particulate matter is suspected to have originated from industrial/commercial products, entering the waste stream as PFOS containing particles. PMID:22154107

Xiao, Feng; Simcik, Matt F; Gulliver, John S

2012-12-15

69

Generation of Bladder Urothelium from Human Pluripotent Stem Cells under Chemically Defined Serum- and Feeder-Free System  

PubMed Central

Human stem cells are promising sources for bladder regeneration. Among several possible sources, pluripotent stem cells are the most fascinating because they can differentiate into any cell type, and proliferate limitlessly in vitro. Here, we developed a protocol for differentiation of human pluripotent stem cells (hPSCs) into bladder urothelial cells (BUCs) under a chemically defined culture system. We first differentiated hPSCs into definitive endoderm (DE), and further specified DE cells into BUCs by treating retinoic acid under a keratinocyte-specific serum free medium. hPSC-derived DE cells showed significantly expressed DE-specific genes, but did not express mesodermal or ectodermal genes. After DE cells were specified into BUCs, they notably expressed urothelium-specific genes such as UPIb, UPII, UPIIIa, P63 and CK7. Immunocytochemistry showed that BUCs expressed UPII, CK8/18 and P63 as well as tight junction molecules, E-CADHERIN and ZO-1. Additionally, hPSCs-derived BUCs exhibited low permeability in a FITC-dextran permeability assay, indicating BUCs possessed the functional units of barrier on their surfaces. However, BUCs did not express the marker genes of other endodermal lineage cells (intestine and liver) as well as mesodermal or ectodermal lineage cells. In summary, we sequentially differentiated hPSCs into DE and BUCs in a serum- and feeder-free condition. Our differentiation protocol will be useful for producing cells for bladder regeneration and studying normal and pathological development of the human bladder urothelium in vitro. PMID:24776760

Kang, Minyong; Kim, Hyeon Hoe; Han, Yong-Mahn

2014-01-01

70

A serum metabolomic investigation on hepatocellular carcinoma patients by chemical derivatization followed by gas chromatography/mass spectrometry.  

PubMed

The purpose of this study was to investigate the serum metabolic difference between hepatocellular carcinoma (HCC, n = 20) male patients and normal male subjects (n = 20). Serum metabolome was detected through chemical derivatization followed by gas chromatography/mass spectrometry (GC/MS). The acquired GC/MS data was analyzed by stepwise discriminant analysis (SDA) and support vector machine (SVM). The metabolites including butanoic acid, ethanimidic acid, glycerol, L-isoleucine, L-valine, aminomalonic acid, D-erythrose, hexadecanoic acid, octadecanoic acid, and 9,12-octadecadienoic acid in combination with each other gave the strongest segregation between the two groups. By applying these variables, our method provided a diagnostic model that could well discriminate between HCC patients and normal subjects. More importantly, the error count estimate for each group was 0%. The total classifying accuracy of the discriminant function tested by SVM 20-fold cross validation was 75%. This technique is different from traditional ones and appears to be a useful tool in the area of HCC diagnosis. PMID:18767022

Xue, Ruyi; Lin, Zhenxin; Deng, Chunhui; Dong, Ling; Liu, Taotao; Wang, Jiyao; Shen, Xizhong

2008-10-01

71

EVALUATION OF PERFLUOROALKYL ACID ACTIVITY USING PRIMARY MOUSE AND HUMAN HEPATOCYTES  

EPA Science Inventory

While perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been studied at length, less is know about the biological activity of other environmental perfluoroalkyl acids (pFAAs). Using a transient transfection assay developed in COS-l cells, our group has previ...

72

Testing for departures from additivity in mixtures of perfluoroalkyl acids (PFAAs)  

EPA Science Inventory

This study is a follow-up to a paper by Carr, et al. that determined a design structure to optimally test for departures from additivity in a fixed ratio mixture of four perfluoroalkyl acids (PFAAs) using an in vitro transiently-transfected COS- 1 PPARa reporter model with an NHA...

73

Occurrence of Perfluoroalkyl Surfactants in Water, Fish, and Birds from New York State  

Microsoft Academic Search

Concentrations of perfluorooctanesulfonate (PFOS) and several other perfluoroalkyl surfactants (PASs) were determined in nine\\u000a major water bodies (n = 51) of New York State (NYS). These PASs were also measured in the livers of two species of sport fish (n = 66) from 20 inland lakes in NYS. Finally, perfluorinated compounds were measured in the livers of 10 species of

Ewan Sinclair; David T. Mayack; Kenneth Roblee; Nobuyoshi Yamashita; Kurunthachalam Kannan

2006-01-01

74

Evaluation of Perfluoroalkyl Acid Activity Using Primary Mouse and Human Hepatocytes.  

EPA Science Inventory

While perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been studied at length, less is known about the biological activity of other perfluoroalkyl acids (PFAAs) in the environment. Using a transient transfection assay developed in COS-1 cells, our group h...

75

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

76

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...

77

Chemical modification resolves the asymmetry of siRNA strand degradation in human blood serum  

Microsoft Academic Search

Small interfering (si)RNAs have recently been used to therapeutically silence genes in vivo after intravenous systemic delivery. Further progress in the development of siRNA therapeutics will in part rely on tailoring site-specific chemical modifications of siRNAs to optimize their pharmacokinetic properties. Advances are particularly needed to improve the nucleolytic stability of these double-stranded RNA drugs in vivo and suppress adverse

JOHN A. H. HOERTER; NILS G. WALTER

2009-01-01

78

Association of perfluorooctanoic acid and perfluorooctane sulfonate with serum lipids among adults living near a chemical plant.  

PubMed

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are compounds that do not occur in nature but have been widely used since World War II and persist indefinitely in the environment. They are present in the serum of Americans with median levels of 4 ng/mL and 21 ng/mL, respectively. PFOA has been positively associated with cholesterol in several studies of workers. A cross-sectional study of lipids and PFOA and PFOS was conducted among 46,294 community residents aged 18 years or above, who drank water contaminated with PFOA from a chemical plant in West Virginia. The mean levels of serum PFOA and PFOS in 2005-2006 were 80 ng/mL (median, 27 ng/mL) and 22 ng/mL (median, 20 ng/mL), respectively. All lipid outcomes except high density lipoprotein cholesterol showed significant increasing trends by increasing decile of either compound; high density lipoprotein cholesterol showed no association. The predicted increase in cholesterol from lowest to highest decile for either compound was 11-12 mg/dL. The odds ratios for high cholesterol (>/=240 mg/dL), by increasing quartile of PFOA, were 1.00, 1.21 (95% confidence interval (CI): 1.12, 1.31), 1.33 (95% CI: 1.23, 1.43), and 1.40 (95% CI: 1.29, 1.51) and were similar for PFOS quartiles. Because these data are cross-sectional, causal inference is limited. Nonetheless, the associations between these compounds and lipids raise concerns, given their common presence in the general population. PMID:19846564

Steenland, Kyle; Tinker, Sarah; Frisbee, Stephanie; Ducatman, Alan; Vaccarino, Viola

2009-11-15

79

Norepinephrine stimulates progesterone production in highly estrogenic bovine granulosa cells cultured under serum-free, chemically defined conditions  

PubMed Central

Background Since noradrenergic innervation was described in the ovarian follicle, the actions of the intraovarian catecholaminergic system have been the focus of a variety of studies. We aimed to determine the gonadotropin-independent effects of the catecholamine norepinephrine (NE) in the steroid hormone profile of a serum-free granulosa cell (GC) culture system in the context of follicular development and dominance. Methods Primary bovine GCs were cultivated in a serum-free, chemically defined culture system supplemented with 0.1% polyvinyl alcohol. The culture features were assessed by hormone measurements and ultrastructural characteristics of GCs. Results GCs produced increasing amounts of estradiol and pregnenolone for 144h and maintained ultrastructural features of healthy steroidogenic cells. Progesterone production was also detected, although it significantly increased only after 96h of culture. There was a highly significant positive correlation between estradiol and pregnenolone production in high E2-producing cultures. The effects of NE were further evaluated in a dose–response study. The highest tested concentration of NE (10 (?7) M) resulted in a significant increase in progesterone production, but not in estradiol or pregnenolone production. The specificity of NE effects on progesterone productio n was further investigated by incubating GCs with propranolol (10 (?8) M), a non-selective beta-adrenergic antagonist. Conclusions The present culture system represents a robust model to study the impact of intrafollicular factors, such as catecholamines, in ovarian steroidogenesis and follicular development. The results of noradrenergic effects in the steroidogenesis of GC have implications on physiological follicular fate and on certain pathological ovarian conditions such as cyst formation and anovulation. PMID:23171052

2012-01-01

80

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

81

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 650pg/g and 17 to 2000pg/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 3800ng /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, 1500ng/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; Skrbi?, Biljana; Oliveira, Luis Silva; da Boit Martinello, Kátia; Al-Dhabi, Naif A; Anti?, Igor; Farré, Marinella; Barceló, Damià

2014-11-01

82

Food risk assessment for perfluoroalkyl acids and brominated flame retardants in the French population: results from the second French total diet study.  

PubMed

To determine the exposure of the French population to toxic compounds contaminating the food chain, a total diet study was performed in France between 2007 and 2009. This study was designed to reflect the consumption habits of the French population and covered the most important foods in terms of consumption, selected nutrients and contribution to contamination. Based on French consumption data, the present study reports the dietary exposure to perfluoroalkyl acids (16 congeners) and brominated flame retardants (polybrominated diphenyl ethers, hexabromocyclododecane and polybrominated biphenyls). Comparison of the calculated dietary exposures with the generally accepted health-based guidance values revealed that most compounds do not pose any risk. There are however knowledge gaps for some congeners in these large chemical classes. PMID:24529894

Rivière, G; Sirot, V; Tard, A; Jean, J; Marchand, P; Veyrand, B; Le Bizec, B; Leblanc, J C

2014-09-01

83

Combination of fluoroalkylation and Kornblum-DeLaMare reaction: a new strategy for the construction of (Z)-?-perfluoroalkyl enaminones.  

PubMed

A novel strategy has been developed for the highly chemo- and stereo-selective synthesis of (Z)-?-perfluoroalkyl enaminones from readily available starting materials via a multicomponent radical reaction involving sequential fluoroalkylation and Kornblum-DeLaMare reaction. Notably, this methodology involves the concurrent cleavage of at least three chemical bonds, including two C-F bonds and one C-X (X = Br or I) bond, as well as the formation of three new bonds, including one C[double bond, length as m-dash]O bond, one C[double bond, length as m-dash]C bond and one C-N bond, in one pot. PMID:25470313

Liu, Chunmei; Shi, Erbo; Xu, Feng; Luo, Qiang; Wang, Hongxiang; Chen, Jijun; Wan, Xiaobing

2014-12-23

84

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

85

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

86

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

PubMed

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

87

Efficient hydrolysis of the chemical warfare nerve agent tabun by recombinant and purified human and rabbit serum paraoxonase 1.  

PubMed

Paraoxonase 1 (PON1) has been described as an efficient catalytic bioscavenger due to its ability to hydrolyze organophosphates (OPs) and chemical warfare nerve agents (CWNAs). It is the future most promising candidate as prophylactic medical countermeasure against highly toxic OPs and CWNAs. Most of the studies conducted so far have been focused on the hydrolyzing potential of PON1 against nerve agents, sarin, soman, and VX. Here, we investigated the hydrolysis of tabun by PON1 with the objective of comparing the hydrolysis potential of human and rabbit serum purified and recombinant human PON1. The hydrolysis potential of PON1 against tabun, sarin, and soman was evaluated by using an acetylcholinesterase (AChE) back-titration Ellman method. Efficient hydrolysis of tabun (100 nM) was observed with ?25-40 mU of PON1, while higher concentration (80-250 mU) of the enzyme was required for the complete hydrolysis of sarin (11 nM) and soman (3 nM). Our data indicate that tabun hydrolysis with PON1 was ?30-60 times and ?200-260 times more efficient than that with sarin and soman, respectively. Moreover, the catalytic activity of PON1 varies from source to source, which also reflects their efficiency of hydrolyzing different types of nerve agents. Thus, efficient hydrolysis of tabun by PON1 suggests its promising potential as a prophylactic treatment against tabun exposure. PMID:21040699

Valiyaveettil, Manojkumar; Alamneh, Yonas; Biggemann, Lionel; Soojhawon, Iswarduth; Doctor, Bhupendra P; Nambiar, Madhusoodana P

2010-12-01

88

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, Bjørn A; Herzke, Dorte; Eisert, Regina; Oftedal, Olav

2015-02-01

89

Bioaccumulation of perfluoroalkyl carboxylates (PFCAs) and perfluoroalkane sulfonates (PFSAs) by earthworms (Eisenia fetida) in soil.  

PubMed

Earthworms were exposed to artificially contaminated soils with ten perfluoroalkyl substances (PFASs). PFASs with longer perfluorinated carbon chain displayed higher uptake rate coefficients (k(u)), longer half-life (t(½)) and time to steady-state (t(ss)) but lower elimination rate coefficients (k(e)) than the shorter ones. Similarly, perfluorosulfonates acids (PFSAs) displayed higher ku, longer t(½) and tss but lower ke than perflurocarboxylic acids (PFCAs) with the same perfluorinated chain length. All the studied PFASs, including those with seven or less perfluorinated carbons, were bioaccumulated in the earthworms and the biota-to-soil accumulation factors (BSAFs) increased with perfluorinated carbon chain length and were greater for PFSAs than for PFCAs of equal perfluoroalkyl chain length. The BSAFs were found to be dependent on the concentrations of PFASs in soil and decreased as the level of PFASs in soil increased. PMID:23644275

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

2013-08-01

90

Dietary exposure to perfluoroalkyl acids of specific French adult sub-populations: high seafood consumers, high freshwater fish consumers and pregnant women.  

PubMed

Perfluoroalkyl acids (PFAAs) are globally found in various media, including food and especially fishery products. In the present study, the dietary exposure to 15 perfluoroalkyl acids was assessed for 3 French adult populations, namely high seafood consumers, high freshwater fish consumers, and pregnant women. Purified food extracts were analysed by LC-MS/MS and PFBA, PFPA, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFTrDA, PFTeDA, PFBS, PFHxS, PFHpS, PFOS and PFDS were monitored and quantified according to the isotope dilution principle. Under lower bound (LB) hypothesis (i.e. contamination valueschemicals. PMID:24530183

Yamada, A; Bemrah, N; Veyrand, B; Pollono, C; Merlo, M; Desvignes, V; Sirot, V; Marchand, P; Berrebi, A; Cariou, R; Antignac, J P; Le Bizec, B; Leblanc, J C

2014-09-01

91

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 (...

92

Conformational analysis of single perfluoroalkyl chains by single-molecule real-time transmission electron microscopic imaging.  

PubMed

Whereas a statistical average of molecular ensembles has been the conventional source of information on molecular structures, atomic resolution movies of single organic molecules obtained by single-molecule real-time transmission electron microscopy have recently emerged as a new tool to study the time evolution of the structures of individual molecules. The present work describes a proof-of-principle study of the determination of the conformation of each C-C bond in single perfluoroalkyl fullerene molecules encapsulated in a single-walled carbon nanotube (CNT) as well as those attached to the outer surface of a carbon nanohorn (CNH). Analysis of 82 individual molecules in CNTs under a 120 kV electron beam indicated that 6% of the CF2-CF2 bonds and about 20% of the CH2-CH2 bonds in the corresponding hydrocarbon analogue are in the gauche conformation. This comparison qualitatively matches the known conformational data based on time- and molecular-average as determined for ensembles. The transmission electron microscopy images also showed that the molecules entered the CNTs predominantly in one orientation. The molecules attached on a CNH surface moved more freely and exhibited more diverse conformation than those in a CNT, suggesting the potential applicability of this method for the determination of the dynamic shape of flexible molecules and of detailed conformations. We observed little sign of any decomposition of the specimen molecules, at least up to 10(7) e·nm(-2) (electrons/nm(2)) at 120 kV acceleration voltage. Decomposition of CNHs under irradiation with a 300 kV electron beam was suppressed by cooling to 77 K, suggesting that the decomposition is a chemical process. Several lines of evidence suggest that the graphitic substrate and the attached molecules are very cold. PMID:24341551

Harano, Koji; Takenaga, Shinya; Okada, Satoshi; Niimi, Yoshiko; Yoshikai, Naohiko; Isobe, Hiroyuki; Suenaga, Kazu; Kataura, Hiromichi; Koshino, Masanori; Nakamura, Eiichi

2014-01-01

93

Contamination profiles of perfluoroalkyl substances in five typical rivers of the Pearl River Delta region, South China.  

PubMed

A survey on contamination profiles of eighteen perfluoroalkyl substances (PFASs) was performed via high performance liquid chromatography-tandem mass spectrometry for surface water and sediments from five typical rivers of the Pearl River Delta region, South China in summer and winter in 2012. The total concentrations of the PFASs in the water phase of the five rivers ranged from 0.14 to 346.72 ng L(-1). The PFAS concentrations in the water phase were correlated positively to some selected water quality parameters such as chemical oxygen demand (COD) (0.7913) and conductivity (0.5642). The monitoring results for the water samples showed significant seasonal variations, while those for the sediment samples showed no obvious seasonal variations. Among the selected 18 PFASs, perfluorooctane sulfonic acid (PFOS) was the dominant PFAS compound both in water and sediment for two seasons with its maximum concentration of 320.5 ng L(-1) in water and 11.4 ng g(-1) dry weight (dw) in sediment, followed by perfluorooctanoic acid (PFOA) with its maximum concentration of 26.48 ng L(-1) in water and 0.99 ng g(-1) dw in sediment. PFOS and PFOA were found at relatively higher concentrations in the Shima River and Danshui River than in the other three rivers (Xizhijiang River, Dongjiang River and Shahe River). The principal component analysis for the PFASs concentrations in water and sediment separated the sampling sites into two groups: rural and agricultural area, and urban and industrial area, suggesting the PFASs in the riverine environment were mainly originated from industrial and urban activities in the region. PMID:25113179

Pan, Chang-Gui; Ying, Guang-Guo; Liu, You-Sheng; Zhang, Qian-Qian; Chen, Zhi-Feng; Peng, Feng-Jiao; Huang, Guo-Yong

2014-11-01

94

Estrogen-Like Activity of Perfluoroalkyl Acids In Vivo and Interaction with Human and Rainbow Trout Estrogen Receptors In Vitro  

PubMed Central

The objectives of this study were to determine the structural characteristics of perfluoroalkyl acids (PFAAs) that confer estrogen-like activity in vivo using juvenile rainbow trout (Oncorhynchus mykiss) as an animal model and to determine whether these chemicals interact directly with the estrogen receptor (ER) using in vitro and in silico species comparison approaches. Perfluorooctanoic (PFOA), perfluorononanoic (PFNA), perfluorodecanoic (PFDA), and perfluoroundecanoic (PFUnDA) acids were all potent inducers of the estrogen-responsive biomarker protein vitellogenin (Vtg) in vivo, although at fairly high dietary exposures. A structure-activity relationship for PFAAs was observed, where eight to ten fluorinated carbons and a carboxylic acid end group were optimal for maximal Vtg induction. These in vivo findings were corroborated by in vitro mechanistic assays for trout and human ER. All PFAAs tested weakly bound to trout liver ER with half maximal inhibitory concentration (IC50) values of 15.2–289?M. Additionally, PFOA, PFNA, PFDA, PFUnDA, and perlfuorooctane sulfonate (PFOS) significantly enhanced human ER?-dependent transcriptional activation at concentrations ranging from 10–1000nM. Finally, we employed an in silico computational model based upon the crystal structure for the human ER? ligand-binding domain complexed with E2 to structurally investigate binding of these putative ligands to human, mouse, and trout ER?. PFOA, PFNA, PFDA, and PFOS all efficiently docked with ER? from different species and formed a hydrogen bond at residue Arg394/398/407 (human/mouse/trout) in a manner similar to the environmental estrogens bisphenol A and nonylphenol. Overall, these data support the contention that several PFAAs are weak environmental xenoestrogens of potential concern. PMID:21163906

Benninghoff, Abby D.; Bisson, William H.; Koch, Daniel C.; Ehresman, David J.; Kolluri, Siva K.; Williams, David E.

2011-01-01

95

Negative ion chemical ionization-gas chromatographic-mass spectrometric determination of residues of different pyrethroid insecticides in whole blood and serum.  

PubMed

A new rapid and sensitive analytical method using negative ion chemical ionization-gas chromatography-mass spectrometry in selective ion monitoring mode has been developed for the determination of residues of different synthetic pyrethroid insecticides, allethrin, bifenthrin, cypermethrin, cyphonothrin, cyfluthrin, lambda-cyhalothrin, deltamethrin, fenvalerate, fenpropathrin, permethrin, prallethrin, and trans-fluthrin, in whole blood. The residues of pyrethroid molecules were extracted from the whole blood using a hexane and acetone (8:2, v/v) solvent mixture without separating the serum. The method was found sensitive to detect the residues of pyrethroids up to the level 0.2 pg/mL. Experiments conducted with the whole blood samples at the fortification level 1-100 pg/mL showed 91-103% recovery, whereas blood serum samples collected after the fortification of pyrethroids in whole blood showed 36-54% recovery. Recovery experiments conducted by direct fortification of pyrethroids in blood serum samples showed 96-108%. The applications of the analytical method was tested by analyzing 73 human blood samples collected from the population exposed continuously to different pyrethroid-based formulations. None of the blood samples showed residues of pyrethroids. The results were also confirmed by the detection of the appropriate amounts in a number of these samples, which had subsequently been spiked with known quantity of pyrethroids. PMID:15538961

Ramesh, Atmakuru; Ravi, Perumal Elumalai

2004-01-01

96

Effect of body condition on tissue distribution of perfluoroalkyl substances (PFASs) in Arctic fox (Vulpes lagopus).  

PubMed

Arctic animals undergo large seasonal fluctuations in body weight. The effect of body condition on the distribution and composition of 16 perfluoroalkyl substances (PFASs) was investigated in liver, blood, kidney, adipose tissue, and muscle of Arctic foxes (Vulpes lagopus) from Svalbard (n = 18, age 1-3 years). PFAS concentrations were generally highest in liver, followed by blood and kidney, while lowest concentrations were found in adipose tissue and muscle. Concentrations of summed perfluorocarboxylic acids and perfluoroalkyl sulfonates were five and seven times higher, respectively, in adipose tissue of lean compared to fat foxes. In addition, perfluorodecanoate (PFDA) and perfluoroheptanesulfonate (PFHpS) concentrations in liver, kidney, and blood, and, perfluorononanoate (PFNA) in liver and blood, were twice as high in the lean compared to the fat foxes. The ratio between perfluorooctane sulfonamide (FOSA) and its metabolite perfluorooctanesulfonate (PFOS) was lowest in liver, muscle, and kidney, while significantly higher proportions of FOSA were found in adipose tissue and blood. The results of the present study suggest that toxic potential of exposure to PFAS among other pollutants in Arctic mammals may increase during seasonal emaciation. The results also suggest that body condition should be taken into account when assessing temporal trends of PFASs. PMID:25215880

Aas, Camilla Bakken; Fuglei, Eva; Herzke, Dorte; Yoccoz, Nigel G; Routti, Heli

2014-10-01

97

Occurrence and transport of perfluoroalkyl acids (PFAAs), including short-chain PFAAs in Tangxun Lake, China.  

PubMed

Short-chain perfluoroalkyl acids (PFAAs), which have less than seven fluorinated carbons, have been introduced as substitutes for eight-carbon homologue products. In this study, water, sediment, and biological samples (fish and plant) were collected from Tangxun Lake, which is located near a production base of the fluorochemical industry in Wuhan, China. Perfluorobutane sulfonate (PFBS) and perfluorobutanoic acid (PFBA) were the predominant PFAAs in surface water, with average concentrations of 3660 ng/L and 4770 ng/L, respectively. However, perfluorooctane sulfonate (PFOS) was the most abundant PFAA in sediments, with an average concentration of 74.4 ng/g dw. The organic carbon normalized distribution coefficients (KOC) indicated that short-chain PFAAs (CF2 < 7) tended to have lower adsorption potentials than PFOS, perfluorooctanoic acid (PFOA), and longer perfluoroalkyl chain compounds. PFBS and PFBA could transport to a farther distance in the horizontal direction along the water flow and infiltrate into deeper depths in the vertical direction. However, levels of PFOS and PFOA in water dropped exponentially along the current, and their proportions were decreased gradually with the increasing depth in sediment cores. Furthermore, values of log bioconcentration factor (BCF) of the short-chain PFAAs were all relatively low (<1), indicating no bioaccumulation potentials for short-chain PFAAs in aquatic species. PMID:23883102

Zhou, Zhen; Liang, Yong; Shi, Yali; Xu, Lin; Cai, Yaqi

2013-08-20

98

Tissue-specific concentrations and patterns of perfluoroalkyl carboxylates and sulfonates in East Greenland polar bears.  

PubMed

Several perfluoroalkyl carboxylates (PFCAs) and perfluoroalkyl sulfonates (PFSAs) of varying chain length are bioaccumulative in biota. However, wildlife reports have focused on liver and with very little examination of other tissues, and thus there is a limited understanding of their distribution and potential effects in the mammalian body. In the present study, the comparative accumulation of C(6) to C(15) PFCAs, C(4), C(6), C(8) and C(10) PFSAs, and select precursors were examined in the liver, blood, muscle, adipose, and brain of 20 polar bears (Ursus maritimus) from Scoresby Sound, Central East Greenland. Overall, PFSA and PFCA concentrations were highest in liver followed by blood > brain > muscle ? adipose. Liver and blood samples contained proportionally more of the shorter/medium chain length (C(6) to C(11)) PFCAs, whereas adipose and brain samples were dominated by longer chain (C(13) to C(15)) PFCAs. PFCAs with lower lipophilicities accumulated more in the liver, whereas the brain accumulated PFCAs with higher lipophilicities. The concentration ratios (±SE) between perfluorooctane sulfonate and its precursor perfluorooctane sulfonamide varied among tissues from 9 (±1):1 (muscle) to 36 (±7):1 (liver). PFCA and PFSA patterns in polar bears indicate that the pharmacokinetics of these compounds are to some extent tissue-specific, and are the result of several factors that may include differing protein interactions throughout the body. PMID:23057644

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

2012-11-01

99

The measurement of iron-binding capacity in serum and purified transferrin with the aid of chemical affinity chromatography.  

PubMed Central

In a mew method for the estimation of transferrin by iron-binding capacity iron is added as the tartrate in NaCl with about 10 mM bicarbonate. The excess iron is removed by passage through DEAE-Sephadex A-50 previously treated with the iron chelator disodium catechol-3,5-disulphonate. The iron remaining bound to transferrin is measured without protein precipitation by the use of ferrozine. The method is applicable to fresh, frozen, or lyophilized serum, purified transferrin, and some quality control preparations. Validation experiments confirm that transferrin in serum and in pure solution is saturated with iron and give some evidence of specificity. The possible use of commercially available transferrin preparations as analytical reference standards is discussed. PMID:1127111

Ramsay, W N

1975-01-01

100

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

101

Recent developments in trace analysis of poly- and perfluoroalkyl substances.  

PubMed

Recent developments, improvements, and trends in the ultra-trace determination of per- and polyfluoroalkyl substances (PFASs) in environmental and human samples are highlighted and the remaining challenges and uncertainties are outlined and discussed. Understanding the analytical implications of such things as adsorption of PFASs to surfaces, effects of differing matrices, varying PFAS isomer response factors, potential bias effects of sampling, sample preparation, and analysis is critical to measuring highly fluorinated compounds at trace levels. These intricate analytical issues and the potential consequences of ignoring to deal with them correctly are discussed and documented with examples. Isomer-specific analysis and the development of robust multi-chemical methods are identified as topical trends in method development for an ever-increasing number of PFASs of environmental and human interest. Ultimately, the state-of-the-art of current analytical method accuracy is discussed on the basis of results from interlaboratory comparison studies. PMID:21400077

Berger, Urs; Kaiser, Mary A; Kärrman, Anna; Barber, Jonathan L; van Leeuwen, Stefan P J

2011-06-01

102

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

103

Perfluoroalkyl substances in daling river adjacent to fluorine industrial parks: implication from industrial emission.  

PubMed

The pollution level and source of perfluoroalkyl substances (PFASs) in mainstream and tributary of Daling River in northeast China were investigated in present study. Concentrations of PFASs in surface water and sediment ranged from 4.6 to 3,410 ng/L and from 0.08 to 2.6 ng/g dry weight, respectively. The lowest levels of PFASs were found in vicinity of a drinking water source located in upstream of Daling River. Xihe tributary, which is adjacent to two local fluorine industrial parks, contained the highest level of PFASs. Short-chain PFASs, including perfluorobutanoic acid and perfluorobutane sulfonate, were of higher levels due to their emerging as alternative products for perfluorooctane sulfonate. High level of perfluorooctanoic acid was also found in Daling River. Based on these results, it can be concluded that the relatively severe pollutions of Xihe tributary were caused by long-term development of the two local fluorine industry parks. PMID:25421711

Meng, Jing; Wang, Tieyu; Wang, Pei; Zhu, Zhaoyun; Li, Qifeng; Lu, Yonglong

2015-01-01

104

Interactions of DPPC with semitelechelic poly(glycerol methacrylate)s with perfluoroalkyl end groups.  

PubMed

Semitelechelic poly(glycerol methacrylate)s having a perfluoroalkyl end group (PGMA(n)-F(9)) were synthesized by ATRP. The interactions of these polymers with different degrees of polymerization with chiral or racemic dipalmitoylphosphatidylcholine (l-DPPC, d-DPPC, or rac-DPPC) monolayers at the air/water interface were studied. Langmuir trough measurements coupled with epifluorescence microscopy allowed for the observation of domain formation within the coexistence region of liquid-expanded (LE) and liquid-condensed (LC) states of DPPC in mixed DPPC-polymer films prepared by spreading a solution of both compounds in the same organic solvent (cospread films). Because of the incorporation of PGMA(n)-F(9) polymers into the LE phase and their line-active behavior, a formation of novel types of domains could be observed. During compression, a thinning out of the tips of two- to six-lobed flowerlike domain structures and consecutive spiral formation appeared for l- and d-DPPC within the two-phase coexistence region (LE/LC) of the monolayer. When rac-DPPC was used, symmetrical stripe formation was induced at the vertices of the domains and fingerprint-like structures were created by convection-inducing movements of the domains at the air/water interface. Additional investigations of the interaction of PGMA(n)-F(9) with DPPC vesicles using differential scanning calorimetry (DSC) supported the finding on the monolayer system that the incorporation of the polymers into the lipid monolayers is not solely driven by the perfluoroalkyl chain but significantly by the hydrophilic polymer part. Apparently, interactions of the PGMA chain with the lipid headgroups are important as the interactions increase with the elongation of the polymer chain, indicating that the polymer also has hydrophobic character. PMID:23046205

Scholtysek, Peggy; Li, Zheng; Kressler, Jörg; Blume, Alfred

2012-11-01

105

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. Environ Toxicol Chem 2015;34:184-191. © 2014 SETAC. PMID:25323676

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

2015-01-01

106

Transcriptional and cellular responses of the green alga Chlamydomonas reinhardtii to perfluoroalkyl phosphonic acids.  

PubMed

Perfluoroalkyl phosphonic acids (PFPAs), a new class of perfluoroalkyl substances used primarily in the industrial sector as surfactants, were recently detected in surface water and wastewater treatment plant effluents. Toxicological effects of PFPAs have as yet not been investigated in aquatic organisms. The objective of the present study was to evaluate the effects of perfluorooctylphosphonic acid (C8-PFPA) and perfluorodecylphosphonic acid (C10-PFPA) exposure (31-250?g/L) on Chlamydomonas reinhardtii using genomic (qRT-PCR), biochemical (reactive oxygen species production (ROS) and lipid peroxidation), and physiological (cellular viability) indicators. After 72h of exposure, no differences were observed in cellular viability for any of the two perfluorochemicals. However, increase in ROS concentrations (36% and 25.6% at 125 and 250?g/L, respectively) and lipid peroxidation (35.5% and 35.7% at 125 and 250?g/L, respectively) was observed following exposure to C10-PFPA. C8-PFPA exposure did not impact ROS production and lipid peroxidation in algae. To get insights into the molecular response and modes of action of PFPA toxicity, qRT-PCR-based assays were performed to analyze the transcription of genes related to antioxidant responses including superoxide dismutase (SOD-1), glutathione peroxidase (GPX), catalase (CAT), glutathione S-transferase (GST), and ascorbate peroxidase (APX I). Genomic analyses revealed that the transcription of CAT and APX I was up-regulated for all the C10-PFPA concentrations. In addition, PFPAs were quantified in St. Lawrence River surface water samples and detected at concentrations ranging from 250 to 850pg/L for C8-PFPA and 380 to 650pg/L for C10-PFPA. This study supports the prevalence of PFPAs in the aquatic environment and suggests potential impacts of PFPA exposure on the antioxidant defensive system in C. reinhardtii. PMID:25621396

Sanchez, David; Houde, Magali; Douville, Mélanie; De Silva, Amila O; Spencer, Christine; Verreault, Jonathan

2015-03-01

107

Chemically synthesized glycosides of hydroxylated flavylium ions as suitable models of anthocyanins: binding to iron ions and human serum albumin, antioxidant activity in model gastric conditions.  

PubMed

Polyhydroxylated flavylium ions, such as 3',4',7-trihydroxyflavylium chloride (P1) and its more water-soluble 7-O-?-d-glucopyranoside (P2), are readily accessible by chemical synthesis and suitable models of natural anthocyanins in terms of color and species distribution in aqueous solution. Owing to their catechol B-ring, they rapidly bind FeIII, weakly interact with FeII and promote its autoxidation to FeIII. Both pigments inhibit heme-induced lipid peroxidation in mildly acidic conditions (a model of postprandial oxidative stress in the stomach), the colorless (chalcone) forms being more potent than the colored forms. Finally, P1 and P2 are moderate ligands of human serum albumin (HSA), their likely carrier in the blood circulation, with chalcones having a higher affinity for HSA than the corresponding colored forms. PMID:25514218

Al Bittar, Sheiraz; Mora, Nathalie; Loonis, Michèle; Dangles, Olivier

2014-01-01

108

GC-MS analysis of amino acid enantiomers as their N(O,S)-perfluoroacyl perfluoroalkyl esters: application to space exploration  

NASA Astrophysics Data System (ADS)

The search for optical activity in extraterrestrial sample is an important key for the study of the origin of life With this aim detection of chemical biomarkers i e of organic molecules which play an important role in biochemistry will be one of the main goals of future space missions To reach this goal an investigation of a GC-MS method based on the derivatization of amino acids by using a mixture of perfluorinated alcohols and perfluorinated anhydrides has been performed Amino acids are converted in their N O S -perfluoroacyl perfluoroalkyl esters in a single step procedure using different combinations of the derivatization reagents trifluoroacetic anhydride TFAA - 2 2 2-trifluoro-1-ethanol TFE TFAA-2 2 3 3 4 4 4-heptafluoro-1-butanol HFB heptafluorobutyric anhydride HFBA -HFB The obtained derivatives are analyzed using two different chiral columns a Chirasil-L-Val and a gammat cyclodextrin Rt- gamma -DEXsa stationary phases which show different and complementary enantiomeric selectivity The mass spectra of the derivatized compounds are studied and mass fragmentation patterns are proposed significant fragment ions can be identified to detect amino acid derivatives The obtained results are compared in terms of the enantiomeric separation achieved and mass spectrometric response Linearity studies and the measurement of the limit of detection LOD prove that the proposed method is suitable for a quantitative determination of several amino acids enantiomers 1 The use of a PTV Programmed Temperature Vaporiser

Zampolli, M.; Sternberg, R.; Szopa, C.; Pietrogrande, M. C.; Buch, A.; Dondi, F.; Raulin, F.

109

Global emission inventories for C4-C14 perfluoroalkyl carboxylic acid (PFCA) homologues from 1951 to 2030, part II: the remaining pieces of the puzzle.  

PubMed

We identify eleven emission sources of perfluoroalkyl carboxylic acids (PFCAs) that have not been discussed in the past. These sources can be divided into three groups: [i] PFCAs released as ingredients or impurities, e.g., historical and current use of perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA) and their derivatives; [ii] PFCAs formed as degradation products, e.g., atmospheric degradation of some hydrofluorocarbons (HFCs) and hydrofluoroethers (HFEs); and [iii] sources from which PFCAs are released as both impurities and degradation products, e.g., historical and current use of perfluorobutane sulfonyl fluoride (PBSF)- and perfluorohexane sulfonyl fluoride (PHxSF)-based products. Available information confirms that these sources were active in the past or are still active today, but due to a lack of information, it is not yet possible to quantify emissions from these sources. However, our review of the available information on these sources shows that some of the sources may have been significant in the past (e.g., the historical use of PFBA-, PFHxA-, PBSF- and PHxSF-based products), whereas others can be significant in the long-term (e.g., (bio)degradation of various side-chain fluorinated polymers where PFCA precursors are chemically bound to the backbone). In addition, we summarize critical knowledge and data gaps regarding these sources as a basis for future research. PMID:24861268

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

2014-08-01

110

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

111

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

112

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

113

Probe of I( 2P j) atoms using two-photon resonant four-wave mixing spectroscopy following the 266-nm photodissociations of various alkyl and perfluoroalkyl iodides  

NASA Astrophysics Data System (ADS)

Two-photon resonant four-wave mixing spectroscopy has been utilized successfully for probing I and I ? nascent from the 266 nm photodissociations of various alkyl and perfluoroalkyl iodides. The relative quantum yields for I ?, as well as the recoil anisotropy parameters, were extracted. Recoil anisotropy parameters close to the limit value for parallel transition indicates that the ground-state I( 2P 3/2) originates from the curve crossing from the initially prepared 3Q 0 to 1Q 1 state. The curve-crossing probabilities for alkyl and perfluoroalkyl iodides were obtained and tried to explain using the well-known Landau-Zener model. In the cases of perfluoroalkyl iodides, it is necessary to consider the fluorination effect to describe the detailed dynamics observed in this study and has been revealed that the electronic effect due to fluorine atom substitution is dominant, leading to decrease in the curve-crossing probability.

Lee, Kyoung-Seok; Lee, Keon Woo; Lee, Sang Kuk; Jung, Kyung-Hoon; Kim, Tae Kyu

2008-05-01

114

Spatial distribution of perfluoroalkyl contaminants in lake trout from the Great Lakes.  

PubMed

Individual whole body homogenates of 4 year old lake trout (Salvelinus namaycush) samples collected in 2001 from each of the Great Lakes were extracted using a novel fluorophilicity cleanup step and analyzed for perfluoroalkyl compounds (PFCs). Standard addition and internal standardization were used for quantification. Results were reported (+/- SE) for perfluorinated carboxylates (PFCAs), perfluorinated sulfonates (PFSAs), and unsaturated fluorotelomer carboxylates (8:2 and 10:2 FTUCA). The lowest average concentration of sigmaPFC was found in samples from Lake Superior (13+/-1 ng g(-1)), while the highest average concentration was found in samples from Lake Erie (152+/-14 ng g(-1)). Samples from Lake Ontario (60+/-5 ng g(-1)) and Lake Huron (58 +/-10 ng g(-1)) showed similar average sigmaPFC concentrations, although the perfluorinated sulfonate/carboxylate ratios were different. The major perfluoroalkyl contaminant observed was perfluorooctane sulfonate (PFOS) with the highest concentration found in samples from Lake Erie (121+/-14 ng g(-1)), followed by samples from Lake Ontario (46+/-5 ng g(-1)), Lake Huron (39 +/-10 ng g(-1)), Lake Michigan (16+/-3 ng g(-1)), and Lake Superior (5+/-1 ng g(-1)). Perfluorodecane sulfonate (PFDS) was detected in 89% of the samples, with the highest concentration in Lake Erie samples (9.8+/-1.6 ng g(-1)), and lowest concentration in samples from Lake Superior (0.7 +/- 0.1 ng g(-1)). Statistically significant correlations were observed between PFOS and PFDS concentrations, and PFOS concentration and body weight, respectively. The PFCAs were detected in all samples, with the highest total average concentration in samples from Lake Erie (19 ng g(-1)), followed by samples from Lake Huron (16 ng g(-1)), Lake Ontario (10 ng g(-1)), Lake Michigan (9 ng g(-1)) and Lake Superior (7 ng g(-1)). The compounds with significant contributions to the sigmaPFCA concentrations were PFOA and C9-C13-PFCAs. The 8:2 FTUCA was detected at concentrations ranging between 0.1 and 0.2 ng g-1, with the highest level in samples showing also elevated concentrations of PFOA (4.4 ng g(-1) for Lake Michigan vs 1.5 ng g(-1) for all other samples). The 10:2 FTUCA was detected only in 9% of all samples (nd, 45 pg g(-1)). For those PFCs where we determined lake water concentrations, the highest log BAFs were calculated for PFOS (4.1), PFDA (3.9), and PFOSA (3.8). PMID:17396640

Furdui, Vasile I; Stock, Naomi L; Ellis, David A; Butt, Craig M; Whittle, D Michael; Crozier, Patrick W; Reiner, Eric J; Muir, Derek C G; Mabury, Scott A

2007-03-01

115

Specific estrogen-induced cell proliferation of cultured Syrian hamster renal proximal tubular cells in serum-free chemically defined media  

SciTech Connect

It has long been recognized that the renal proximal tubular epithelium of the hamster is a bona fide estrogen target tissue. The effect of estrogens on the growth of proximal tubule cell explants and dissociated single cells derived from these explant outgrowths has been studied in culture. Renal tubular cells were grown on a PF-HR-9 basement membrane under serum-free chemically defined culture conditions. At 7-14 days in culture, cell number was enhanced 3-fold in the presence of either 17{beta}-estradiol or diethylstilbestrol. A similar 3-fold increase in cell number was also seen at 1 nM 17{beta}-estradiol in subcultured dissociated single tubular cells derived from hamster renal tubular explant outgrowths at 21 days in culture. Concomitant exposure of tamoxifen at 3-fold molar excess in culture completely abolished the increase in cell number seen with 17{beta}-estradiol. The proliferation effect of estrogens on proximal tubular cell growth appears to be species specific since 17{beta}-estradiol did not alter the growth of either rat or guinea pig proximal tubules in culture. In addition, at 7-10 days in culture in the presence of 17{beta}-estradiol, ({sup 3}H)thymidine labeling of hamster tubular cells was enhanced 3-fold. These results clearly indicate that estrogens can directly induce primary epithelial cell proliferation at physiologic concentrations and provide strong additional evidence for an important hormonal role in the neoplastic transformation of the hamster kidney.

Oberley, T.D.; Lauchner, L.J.; Pugh, T.D.; Gonzalez, A.; Goldfarb, S. (Univ. of Wisconsin Medical School, Madison (USA)); Li, S.A.; Li, J.J. (Univ. of Minnesota Medical School, Minneapolis (USA))

1989-03-01

116

Selecting reliable physicochemical properties of perfluoroalkyl and polyfluoroalkyl substances (PFASs) based on molecular descriptors.  

PubMed

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a class of global environmental pollutants whose environmental fate and adverse effects are of concern. However, data on the basic physicochemical properties of PFASs are scarce. To fill part of the data gaps, improved quantitative structure-property relationship (QSPR) models for prediction of PFAS properties are developed based on the correlation between reported experimental data and molecular descriptors (fluorine number, molar volume and total surface area). Properties include vapor pressure, aqueous solubility, octanol/water partition coefficient, air/water partition coefficient and octanol/air partition coefficient. The fluorine number-descriptor model is based on good statistical results. However, this model cannot distinguish among PFASs with the same number of attached fluorines. Setting aside the fluorine number-descriptor models, models based on molar volume are statistically better than those based on total surface area. Therefore, The PFAS data obtained from the molar volume descriptor model are more reliable than from fluorine number and total surface area descriptor models. These results are intended to improve the understanding of the behavior and fate of PFASs in the environment, at contaminated sites and during remediation. PMID:25467694

Kim, Minhee; Li, Loretta Y; Grace, John R; Yue, Chaoyang

2014-11-20

117

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

118

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

2014-07-01

119

Occurrence and trends in concentrations of perfluoroalkyl substances (PFASs) in surface waters of eastern China.  

PubMed

Spatial distributions of perfluoroalkyl substances (PFASs) were investigated in surface waters in Shanghai, Jiangsu and Zhejiang Provinces of eastern China during 2011. A total of 39 samples of surface waters, including 29 rivers, 6 lakes and 4 reservoirs were collected. High performance liquid chromatography/negative electrospray ionization-tandem mass spectrometry (HPLC/(-)ESI-MS/MS) was used to identify and quantify PFASs. Concentrations of PFAS were greater in Shanghai than that in Zhejiang Province. Concentrations of the sum of PFASs (?PFASs) in Shanghai and Kunshan ranged from 39 to 212ngL(-1), while in Zhejiang Province, concentrations of ?PFASs ranged from 0.68 to 146ngL(-1). Perfluorooctanoic acid (PFOA) was the prevalent PFAS in Shanghai. In contrast, PFOA and perfluorohexanoic acid (PFHxA) were the prevalent PFASs in Zhejiang Province. Concentrations of perfluorooctane sulfonate (PFOS) ranged from <0.07 to 9.7ngL(-1). Annual mass of ?PFASs transported by rivers that flow into the East China Sea were calculated to be more than 4000kg PFASs. Correlation analyses between concentrations of individual PFASs showed the correlation between PFHxA and PFOA was positive, while the correlation between PFHxA and perfluorooctane sulfonamide (FOSA) was negative in Shanghai, which indicated that PFHxA and PFOA have common sources. Principal component analysis (PCA) was employed to identify important components or factors that explain different compounds, and results showed that PFHxA and FOSA dominated factor loadings. PMID:25218980

Lu, Zhibo; Song, Luning; Zhao, Zhen; Ma, Yuxin; Wang, Juan; Yang, Haizhen; Ma, Hongmei; Cai, Minghong; Codling, Garry; Ebinghaus, Ralf; Xie, Zhiyong; Giesy, John P

2015-01-01

120

Transport of perfluoroalkyl substances (PFAS) from an arctic glacier to downstream locations: implications for sources.  

PubMed

Perfluoroalkyl substances (PFAS) have been globally detected in various environmental matrices, yet their fate and transport to the Arctic is still unclear, especially for the European Arctic. In this study, concentrations of 17 PFAS were quantified in two ice cores (n=26), surface snow (n=9) and surface water samples (n=14) collected along a spatial gradient in Svalbard, Norway. Concentrations of selected ions (Na(+), SO4(2-), etc.) were also determined for tracing the origins and sources of PFAS. Perfluorobutanoate (PFBA), perfluorooctanoate (PFOA) and perfluorononanoate (PFNA) were the dominant compounds found in ice core samples. Taking PFOA, PFNA and perfluorooctane-sulfonate (PFOS) as examples, higher concentrations were detected in the middle layers of the ice cores representing the period of 1997-2000. Lower concentrations of C8-C12 perfluorocarboxylates (PFCAs) were detected in comparison with concentrations measured previously in an ice core from the Canadian Arctic, indicating that contamination levels in the European Arctic are lower. Average PFAS concentrations were found to be lower in surface snow and melted glacier water samples, while increased concentrations were observed in river water downstream near the coastal area. Perfluorohexanesulfonate (PFHxS) was detected in the downstream locations, but not in the glacier, suggesting existence of local sources of this compound. Long-range atmospheric transport of PFAS was the major deposition pathway for the glaciers, while local sources (e.g., skiing activities) were identified in the downstream locations. PMID:23376515

Kwok, Karen Y; Yamazaki, Eriko; Yamashita, Nobuyoshi; Taniyasu, Sachi; Murphy, Margaret B; Horii, Yuichi; Petrick, Gert; Kallerborn, Roland; Kannan, Kurunthachalam; Murano, Kentaro; Lam, Paul K S

2013-03-01

121

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

USGS Publications Warehouse

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.

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

2013-01-01

122

Perfluoroalkyl and polyfluoroalkyl substances in sediments from South Bohai coastal watersheds, China.  

PubMed

This study investigated the concentrations and distribution of Perfluoroalkyl and polyfluoroalkyl substances (PFAS) in sediments of 12 rivers from South Bohai coastal watersheds. The highest concentrations of ?PFAS (31.920 ng g(-1) dw) and PFOA (29.021 ng g(-1) dw) were found in sediments from the Xiaoqing River, which was indicative of local point sources in this region. As for other rivers, concentrations of ?PFAS ranged from 0.218 to 1.583 ng g(-1) dw were found in the coastal sediments and from 0.167 to 1.953 ng g(-1) dw in the riverine sediments. Predominant PFAS from coastal and riverine areas were PFOA and PFBS, with percentages of 30% and 35%, respectively. Partitioning analysis showed the concentrations of PFNA, PFDA and PFHxS were significantly correlated with organic carbon. The results of a preliminary environmental hazard assessment showed that PFOS posed the highest hazard in the Mi River, while PFOA posed a relative higher hazard in the Xiaoqing River. PMID:24411724

Zhu, Zhaoyun; Wang, Tieyu; Wang, Pei; Lu, Yonglong; Giesy, John P

2014-08-30

123

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

124

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

125

Perfluoroalkyl acid contamination and polyunsaturated fatty acid composition of French freshwater and marine fishes.  

PubMed

In this study, French marine and freshwater fish perfluoroalkyl acid (PFAA) contamination are presented along with their fatty acid (FA) composition to provide further elements for a risk/benefit balance of fish consumption to be assessed. The 29 most consumed marine fish species were collected in four metropolitan French coastal areas in 2004 to constitute composite samples. Geographical differences in terms of consumed species and contamination level were taken into account. Three hundred and eighty-seven composite samples corresponding to 16 freshwater fish species collected between 2008 and 2010 in the six major French rivers or their tributaries were selected among the French national agency for water and aquatic environments freshwater fish sample library. The raw edible parts were analyzed for FA composition and PFAA contamination. Results show that freshwater fishes are more contaminated by PFAAs than marine fishes and do not share the same contamination profile. Freshwater fish contamination is mostly driven by perfluorooctane sulfonate (PFOS) (75%), whereas marine fish contamination is split between perfluorooctanoic acid (PFOA) (24%), PFOS (20%), perfluorohexanoic acid (PFHxA) (15%), perfluoropentanoic acid (PFHpA) (11%), and perfluorobutanoic acid (PFBA) (11%). Common carp, pike-perch, European perch, thicklip grey mullet, and common roach presented the most unfavorable balance profile due to their high level of PFAAs and low level of n-3 long-chain polyunsaturated fatty acids (LC-PUFAs). These data could be used, if needed, in an updated opinion on fish consumption that takes into account PFAA contamination. PMID:25004121

Yamada, Ami; Bemrah, Nawel; Veyrand, Bruno; Pollono, Charles; Merlo, Mathilde; Desvignes, Virginie; Sirot, Véronique; Oseredczuk, Marine; Marchand, Philippe; Cariou, Ronan; Antignac, Jean-Phillippe; Le Bizec, Bruno; Leblanc, Jean-Charles

2014-07-30

126

Micropatterning of perfluoroalkyl self-assembled monolayers for arraying proteins and cells on chips  

NASA Astrophysics Data System (ADS)

Organosilane self-assembled monolayers (SAMs) with perfluoroalkyl groups ( Rf) on glass surfaces were used for arraying proteins and cells on chips. Quartz crystal microbalance measurements confirmed the inhibition of protein adsorption on Rf-SAM-modified surfaces and showed efficient adsorption on hydroxyl-, carboxyl-, and amino group-modified surfaces. The characteristics of Rf-modified surfaces were evaluated using solvent contact angle measurement and Fourier transform infrared (FTIR) spectroscopy. The Rf surface was highly water- and oil-resistant, as inferred from the contact angles of water, oleic acid, and hexadecane. Specific peaks of IR spectra were detected in the region from 1160 to 1360 cm -1. Etching with dry plasma completely exfoliated the Rf-SAM, exposing the underlying intact glass surface. Modification conditions were optimized using contact angle and FTIR measurements. After dry plasma processing, the contact angles of all solvents became undetectable, and the IR peaks disappeared. Micrometer scale protein and cell patterns can be fabricated using the proposed method. Protein adsorption on micropatterned Rf-SAM-modified chips was evaluated using fluorescence analysis; protein adsorption was easily controlled by patterning Rf-SAM. PC12 and HeLa cells grew well on micropatterned Rf-SAM-modified chips. Micropatterning of Rf-SAM by dry plasma treatment with photolithography is useful for the spatial arrangement of proteins and cells.

Kira, Atsushi; Okano, Kazunori; Hosokawa, Yoichiroh; Naito, Akira; Fuwa, Koh; Yuyama, Jyunpei; Masuhara, Hiroshi

2009-06-01

127

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 (0.01-3.67ngg(-1)) and biota (0.79-431?gkg(-1)) samples were higher than those found in water (0.01-233ngL(-1)). L-PFOS presented very high levels in biota and water, particularly in the Anoia River where a maximum concentration of 2.71?gL(-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, Damià

2015-01-15

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

Serum sickness  

MedlinePLUS

... after the first exposure to a medication. Injected proteins such as antithymocyte globulin (used to treat organ transplant rejection) and rituximab (used to treat immune disorders and cancers) can cause serum sickness reactions. Blood products may also cause ...

130

A targeted/non-targeted screening method for perfluoroalkyl carboxylic acids and sulfonates in whole fish using quadrupole time-of-flight mass spectrometry and MS(e).  

PubMed

A new method for measuring perfluoroalkyl contaminants (PFCs) in biological matrices has been developed. An ultra-high pressure liquid chromatograph equipped with a quadrupole time-of-flight mass spectrometer (UPLC-QToF) was optimized using a continuous precursor/product ion monitoring mode. Unlike traditional targeted studies that isolate precursor/product ion pairs, the current method alternates between two ionization energy channels to continuously capture standard electrospray ionization (low energy) and collision induced dissociation (high energy) spectra. The result is the indiscriminant acquisition of paired low and high energy spectra for all constituents eluting from the chromatographic system. This technique was evaluated for the routine analysis of perfluoroalkyl species. Using this technique, linear perfluoroalkyl carboxylic acids (C4 to C14) and perfluoroalkyl sulfonates (C4, C6, C8 and C10) exhibited a linear range spanning over three orders of magnitude and were detectable at levels less than 1 pg on column with a root mean squared signal to noise ratio of 5 to 20. Lake trout (Salvelinus namaycush) and National Institutes of Standards and Technology Standard Reference Material 1946 were used to evaluate matrix effects and the accuracy of this method when applied to a whole fish extract. The current method was also evaluated as a diagnostic tool to identify unknown PFCs using experimental fragmentation patterns, mass defect filtering and Kendrick plots. PMID:24352588

Crimmins, Bernard S; Xia, Xiaoyan; Hopke, Philip K; Holsen, Thomas M

2014-02-01

131

Interaction of perfluoroalkyl acids with human liver fatty acid-binding protein.  

PubMed

Perfluoroalkyl acids (PFAAs) are highly persistent and bioaccumulative, resulting in their broad distribution in humans and the environment. The liver is an important target for PFAAs, but the mechanisms behind PFAAs interaction with hepatocyte proteins remain poorly understood. We characterized the binding of PFAAs to human liver fatty acid-binding protein (hL-FABP) and identified critical structural features in their interaction. The binding interaction of PFAAs with hL-FABP was determined by fluorescence displacement and isothermal titration calorimetry (ITC) assay. Molecular simulation was conducted to define interactions at the binding sites. ITC measurement revealed that PFOA/PFNA displayed a moderate affinity for hL-FABP at a 1:1 molar ratio, a weak binding affinity for PFHxS and no binding for PFHxA. Moreover, the interaction was mainly mediated by electrostatic attraction and hydrogen bonding. Substitution of Asn111 with Asp caused loss of binding affinity to PFAA, indicating its crucial role for the initial PFAA binding to the outer binding site. Substitution of Arg122 with Gly caused only one molecule of PFAA to bind to hL-FABP. Molecular simulation showed that substitution of Arg122 increased the volume of the outer binding pocket, making it impossible to form intensive hydrophobic stacking and hydrogen bonds with PFOA, and highlighting its crucial role in the binding process. The binding affinity of PFAAs increased significantly with their carbon number. Arg122 and Asn111 played a pivotal role in these interactions. Our findings may help understand the distribution pattern, bioaccumulation, elimination, and toxicity of PFAAs in humans. PMID:25370009

Sheng, Nan; Li, Juan; Liu, Hui; Zhang, Aiqian; Dai, Jiayin

2014-11-01

132

Perfluoroalkyl acids in the egg yolk of birds from Lake Shihwa, Korea.  

PubMed

Concentrations of perfluoroalkyl acids (PFAs) were measured in egg yolks of three species of birds, the little egret (Egretta garzetta), little ringed plover (Charadrius dubius), and parrot bill (Paradoxornis webbiana), collected in and around Lake Shihwa, Korea, which receives wastewaters from an adjacent industrial complex. Mean concentrations of perfluorooctanesulfonate (PFOS) ranged from 185 to 314 ng/g ww and were similar to those reported for bird eggs from other urban areas. Long-chain perfluorocarboxylic acids (PFCAs) were also found in egg yolks often at great concentrations. Mean concentrations of perfluoroundecanoic acid (PFUnA) ranged from 95 to 201 ng/g ww. Perfluorooctanoic acid was detected in 32 of 44 egg samples, but concentrations were 100-fold less than those of PFOS. Relative concentrations of PFAs in all three species were similar with the predominance of PFOS (45-50%). There was a statistically significant correlation between PFUnA and perfluorodecanoic acid in egg yolks (p < 0.05), suggesting a common source of PFCAs. Using measured egg concentrations and diet concentrations, the ecological risk of the PFOS and PFA mixture to birds in Lake Shihwa was evaluated using two different approaches. Estimated hazard quotients were similar between the two approaches. The concentration of PFOS associated with 90th centile in bird eggs was 100-fold less than the lowest observable adverse effect level determined for birds, and those concentrations were 4-fold less than the suggested toxicity reference values. On the basis of limited toxicological data, current concentrations of PFOS are less than what would be expected to have an adverse effect on birds in the Lake Shihwa region. PMID:18754515

Yoo, Hoon; Kannan, Kurunthachalam; Kim, Seong Kyu; Lee, Kyu Tae; Newsted, John L; Giesy, John P

2008-08-01

133

Perfluoroalkyl acids in subarctic wild male mink (Neovison vison) in relation to age, season and geographical area.  

PubMed

This study investigates the influence of biological and environmental factors on the concentrations of perfluoroalkyl acids (PFAAs) in a top predator; the American mink. Perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS) and perfluoroalkyl carboxylates (PFCAs) with C8-C13 perfluorinated carbon chains were analyzed in livers from wild male mink liver (n=101) from four areas in Sweden representing two inland environments (rural and highly anthropogenic, respectively) and two different coastal environments. Mean PFOS concentrations were 1250ng/g wet weight and some mink from the urban inland area had among the highest PFOS concentrations ever recorded in mink (up to 21 800ng/g wet weight). PFBS was detected in 89% of the samples, but in low concentrations (mean 0.6ng/g ww). There were significant differences in PFAA concentrations between the geographical areas (p<0.001-0.01). Age, body condition and body weight did not influence the concentrations significantly, but there was a seasonal influence on the concentrations of perfluorodecanoic acid (PFDA) and perfluoroundecanoic acid (PFUnDA) (p<0.01 and p<0.05, respectively), with lower concentrations in autumn samples than in samples taken in the winter and spring. It is thus recommended to take possible seasonal differences into account when using mink exposure data. The overall results suggest that the mink is a suitable sentinel species for assessing and monitoring environmental levels of PFAAs. PMID:23928036

Persson, Sara; Rotander, Anna; Kärrman, Anna; van Bavel, Bert; Magnusson, Ulf

2013-09-01

134

Paradigm shift from alkaline (earth) metals to early transition metals in fluoroorganometal chemistry: perfluoroalkyl titanocene(III) reagents prepared via not titanocene(II) but titanocene(III) species.  

PubMed

Perfluoroalkyl (RF) titanocene reagents [Cp2Ti(III)RF] synthesized via [Cp2Ti(III)Cl] rather than [Cp2Ti(II)] show new types of perfluoroalkylation reactions. The [Cp2Ti(III)RF] reagents exhibit a wide variety of reactivity with carbonyl compounds including esters and nitriles, and selectivities far higher than those reported for conventional RFLi and RFMgX reagents. PMID:24459023

Fujiu, Motohiro; Hashimoto, Ryota; Nakamura, Yuzo; Aikawa, Kohsuke; Ito, Shigekazu; Mikami, Koichi

2014-02-17

135

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

136

Perfluoroalkyl acid distribution in various plant compartments of edible crops grown in biosolids-amended soils.  

PubMed

Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var. dulce), tomato (Lycopersicon lycopersicum), and sugar snap pea (Pisum sativum var. macrocarpon) from an industrially impacted biosolids-amended soil, a municipal biosolids-amended soil, and a control soil. Individual concentrations of PFAAs, on a dry weight basis, in mature, edible portions of crops grown in soil amended with PFAA industrially impacted biosolids were highest for perfluorooctanoate (PFOA; 67 ng/g) in radish root, perfluorobutanoate (PFBA; 232 ng/g) in celery shoot, and PFBA (150 ng/g) in pea fruit. Comparatively, PFAA concentrations in edible compartments of crops grown in the municipal biosolids-amended soil and in the control soil were less than 25 ng/g. Bioaccumulation factors (BAFs) were calculated for the root, shoot, and fruit compartments (as applicable) of all crops grown in the industrially impacted soil. BAFs were highest for PFBA in the shoots of all crops, as well as in the fruit compartment of pea. Root-soil concentration factors (RCFs) for tomato and pea were independent of PFAA chain length, while radish and celery RCFs showed a slight decrease with increasing chain length. Shoot-soil concentration factors (SCFs) for all crops showed a decrease with increasing chain length (0.11 to 0.36 log decrease per CF2 group). The biggest decrease (0.54-0.58 log decrease per CF2 group) was seen in fruit-soil concentration factors (FCFs). Crop anatomy and PFAA properties were utilized to explain data trends. In general, fruit crops were found to accumulate fewer long-chain PFAAs than shoot or root crops presumably due to an increasing number of biological barriers as the contaminant is transported throughout the plant (roots to shoots to fruits). These data were incorporated into a preliminary conceptual framework for PFAA accumulation in edible crops. In addition, these data suggest that edible crops grown in soils conventionally amended for nutrients with biosolids (that are not impacted by PFAA industries) are unlikely a significant source of long-chain PFAA exposure to humans. PMID:24918303

Blaine, Andrea C; Rich, Courtney D; Sedlacko, Erin M; Hundal, Lakhwinder S; Kumar, Kuldip; Lau, Christopher; Mills, Marc A; Harris, Kimberly M; Higgins, Christopher P

2014-07-15

137

Uptake of perfluoroalkyl acids into edible crops via land applied biosolids: field and greenhouse studies.  

PubMed

The presence of perfluoroalkyl acids (PFAAs) in biosolids destined for use in agriculture has raised concerns about their potential to enter the terrestrial food chain via bioaccumulation in edible plants. Uptake of PFAAs by greenhouse lettuce ( Lactuca sativa ) and tomato ( Lycopersicon lycopersicum ) grown in an industrially impacted biosolids-amended soil, a municipal biosolids-amended soil, and a control soil was measured. Bioaccumulation factors (BAFs) were calculated for the edible portions of both lettuce and tomato. Dry weight concentrations observed in lettuce grown in a soil amended (biosolids:soil dry weight ratio of 1:10) with PFAA industrially contaminated biosolids were up to 266 and 236 ng/g for perfluorobutanoic acid (PFBA) and perfluoropentanoic acid (PFPeA), respectively, and reached 56 and 211 ng/g for PFBA and PFPeA in tomato, respectively. BAFs for many PFAAs were well above unity, with PFBA having the highest BAF in lettuce (56.8) and PFPeA the highest in tomato (17.1). In addition, the BAFs for PFAAs in greenhouse lettuce decreased approximately 0.3 log units per CF2 group. A limited-scale field study was conducted to verify greenhouse findings. The greatest accumulation was seen for PFBA and PFPeA in both field-grown lettuce and tomato; BAFs for PFBA were highest in both crops. PFAA levels measured in lettuce and tomato grown in field soil amended with only a single application of biosolids (at an agronomic rate for nitrogen) were predominantly below the limit of quantitation (LOQ). In addition, corn ( Zea mays ) stover, corn grains, and soil were collected from several full-scale biosolids-amended farm fields. At these fields, all PFAAs were below the LOQ in the corn grains and only trace amounts of PFBA and PFPeA were detected in the corn stover. This study confirms that the bioaccumulation of PFAAs from biosolids-amended soils depends strongly on PFAA concentrations, soil properties, the type of crop, and analyte. PMID:24206563

Blaine, Andrea C; Rich, Courtney D; Hundal, Lakhwinder S; Lau, Christopher; Mills, Marc A; Harris, Kimberly M; Higgins, Christopher P

2013-12-17

138

Perfluoroalkyl acid uptake in lettuce (Lactuca sativa) and strawberry (Fragaria ananassa) irrigated with reclaimed water.  

PubMed

Using reclaimed water to irrigate food crops presents an exposure pathway for persistent organic contaminants such as perfluoroalkyl acids (PFAAs) to enter the human food chain. This greenhouse study used reclaimed water augmented with varying concentrations (0.2-40 ?g/L) of PFAAs, including perfluorocarboxylates (C3F7COO(-) to C8F17COO(-)) and perfluorosulfonates (C4F9SO2O(-), C6F13SO2O(-), C8F17SO2O(-)), to investigate potential uptake and concentration-response trends in lettuce (Lactuca sativa) and strawberry (Fragaria ananassa). In addition, studies were conducted to evaluate the role of soil organic carbon concentrations on plant uptake of PFAAs. PFAA concentrations in lettuce leaves and strawberry fruit were measured for each aqueous PFAA concentration applied. PFAA plant concentrations increased linearly with the aqueous concentration for all PFAAs, with PFCAs bioaccumulating to a greater degree than PFSAs in the edible portions of the tested plants. Chain-length-dependency trends were evident in both lettuce shoot and strawberry fruit, with decreasing concentrations associated with increasing chain length. Perfluorobutanoate (PFBA) and perfluoropentanoate (PFPeA), both short-chain PFAAs (<8 carbon chain length), accumulated the most compared with other PFAAs tested in the edible parts of both lettuce and strawberry. PFAA concentrations in strawberry root and shoot were also measured at selected PFAA aqueous concentrations (0.4, 4, and 40 ?g/L). Short-chain perfluorocarboxylates were the dominant fraction in the strawberry fruit and shoot compartments, whereas a more even distribution of all PFAAs appeared in the root compartment. Lettuce grown in soils with varying organic carbon contents (0.4%, 2%, 6%) was used to assess the impact of organic carbon sorption on PFAA bioaccumulation. The lettuce grown in soil with the 6% organic carbon content had the lowest bioaccumulation of PFAAs. Bioaccumulation factors for lettuce were correlated to carbon chain length of PFAAs, showing approximately a 0.4 to 0.6 log decrease per CF2 group. This study confirms that PFAAs can enter and bioaccumulate in food crops irrigated with reclaimed water. Bioaccumulation potential depends on analyte functional group and chain length, concentration in the reclaimed water, and organic carbon content of the soil. PMID:25386873

Blaine, Andrea C; Rich, Courtney D; Sedlacko, Erin M; Hyland, Katherine C; Stushnoff, Cecil; Dickenson, Eric R V; Higgins, Christopher P

2014-12-16

139

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

140

Evaluation of perfluoroalkyl acid activity using primary mouse and human hepatocytes.  

PubMed

While perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been studied at length, less is known about the biological activity of other perfluoroalkyl acids (PFAAs) detected in the environment. Using a transient transfection assay developed in COS-1 cells, our group has previously evaluated a variety of PFAAs for activity associated with activation of peroxisome proliferator-activated receptor alpha (PPAR?). Here we use primary heptatocytes to further assess the biological activity of a similar group of PFAAs using custom designed Taqman Low Density Arrays. Primary mouse and human hepatoyctes were cultured for 48h in the presence of varying concentrations of 12 different PFAAs or Wy14,643, a known activator of PPAR?. Total RNA was collected and the expression of 48 mouse or human genes evaluated. Gene selection was based on either in-house liver microarray data (mouse) or published data using primary hepatocytes (human). Gene expression in primary mouse hepatocytes was more restricted than expected. Genes typically regulated in whole tissue by PPAR? agonists were not altered in mouse cells including Acox1, Me1, Acaa1a, Hmgcs1, and Slc27a1. Cyp2b10, a gene regulated by the constitutive androstane receptor and a transcript normally up-regulated by in vivo exposure to PFAAs, was also unchanged in cultured mouse hepatocytes. Cyp4a14, Ehhadh, Pdk4, Cpt1b, and Fabp1 were regulated as expected in mouse cells. A larger group of genes were differentially expressed in human primary hepatocytes, however, little consistency was observed across compounds with respect to which genes produced a significant dose response making the determination of relative biological activity difficult. This likely reflects weaker activation of PPAR? in human versus rodent cells as well as variation among individual cell donors. Unlike mouse cells, CYP2B6 was up-regulated in human hepatocytes by a number of PFAAs as was PPAR?. Rankings were conducted on the limited dataset. In mouse hepatocytes, the pattern was similar to that previously observed in the COS-1 reporter cell assay. With the exception of PFHxA, longer chain PFAA carboxylates were the most active. The pattern was similar in human hepatocytes, although PFDA and PFOS showed higher activity than previously observed while PFOA showed somewhat less activity. These data reflect inherent challenges in using primary hepatocytes to predict toxicological response. PMID:23567314

Rosen, Mitchell B; Das, Kaberi P; Wood, Carmen R; Wolf, Cynthia J; Abbott, Barbara D; Lau, Christopher

2013-06-01

141

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

142

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

143

Exposure and effects of perfluoroalkyl compounds on tree swallows nesting at Lake Johanna in east central Minnesota, USA  

USGS Publications Warehouse

Tree swallow (Tachycineta bicolor) samples were collected at a reference lake and a nearby lake (Lake Johanna) in east central Minnesota, USA contaminated with perfluorinated carboxylic and sulfonic acids. Tissues were analyzed for a suite of 13 perfluoroalkyl compounds (PFCs) to quantify exposure and to determine if there was an association between egg concentrations of PFCs and reproductive success of tree swallows. Concentrations of perfluoroocatane sulfonate (PFOS) were elevated in all tree swallow tissues from Lake Johanna compared to tissues collected at the reference lake. Other PFCs, except for two, were elevated in blood plasma at Lake Johanna compared to the reference lake. PFOS was the dominant PFC (>75%) at Lake Johanna, but accounted for <50% of total PFCs at the reference lake. There was a negative association between concentrations of PFOS in eggs and hatching success. Reduced hatching success was associated with PFOS levels as low as 150 ng/g wet weight.

Custer, Christine M.; Custer, Thomas W.; Schoenfuss, Heiko L.; Poganski, Beth H.; Solem, Laura

2012-01-01

144

Exposure and effects of perfluoroalkyl compounds on tree swallows nesting at Lake Johanna in east central Minnesota, USA.  

PubMed

Tree swallow (Tachycineta bicolor) samples were collected at a reference lake and a nearby lake (Lake Johanna) in east central Minnesota, USA contaminated with perfluorinated carboxylic and sulfonic acids. Tissues were analyzed for a suite of 13 perfluoroalkyl compounds (PFCs) to quantify exposure and to determine if there was an association between egg concentrations of PFCs and reproductive success of tree swallows. Concentrations of perfluoroocatane sulfonate (PFOS) were elevated in all tree swallow tissues from Lake Johanna compared to tissues collected at the reference lake. Other PFCs, except for two, were elevated in blood plasma at Lake Johanna compared to the reference lake. PFOS was the dominant PFC (>75%) at Lake Johanna, but accounted for <50% of total PFCs at the reference lake. There was a negative association between concentrations of PFOS in eggs and hatching success. Reduced hatching success was associated with PFOS levels as low as 150ng/g wet weight. PMID:21296656

Custer, Christine M; Custer, Thomas W; Schoenfuss, Heiko L; Poganski, Beth H; Solem, Laura

2012-07-01

145

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

146

Validation of a screening method based on liquid chromatography coupled to high-resolution mass spectrometry for analysis of perfluoroalkylated substances in biota  

Microsoft Academic Search

A screening method for analysis of perfluoroalkylated substances (PFAS) in biota samples has been developed and validated using liver samples from polar cod (Boreogadus saida) and glaucous gull (Larus hyperboreus). The method was based on extraction of target compounds from homogenised samples into the solvent mixture used as mobile phase in high-performance liquid chromatography (HPLC), i.e. methanol\\/water (50:50; 2mM ammonium

Urs Berger; Marianne Haukås

2005-01-01

147

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

148

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

149

Enhanced face-to-face Pi stacking in perfluoroalkylated organic semiconductor materials: Crystallographic and NMR studies of weak non-covalent interactions in condensed phases  

NASA Astrophysics Data System (ADS)

In this chapter, the synthesis of new perfluoroalkylated hydrocarbon aromatics A) 1,2,4,5-tetrakis(nonafluorobutyl)-benzene (4-C4F 9-Bz), B) 1,3,6,8-tetrakis(nonafluorobutyl)-pyrene (4-C4F 9-pyrene) and two new heteroaromatic compounds C) 3,8-bis(nonafluorobutyl)-1,10-phenanthroline(2-C4F9-1,10-phen) and D) 4,4'-bis(nonafluorobutyl)-2,2'-bipyridine (2-C4F9-bipy) were described, using copper mediated perfluoroalkylation in a mixture of DMSO(anhy) and anhydrous benzotrifluoride (BTF(anhy)). All the compounds were purified by recrystallization and characterized by 1H NMR, 19F NMR, mass spectrometry and elemental analyses. Single-crystals were obtained for these novel compounds and their packing modes are studied and compared with other literature reporting single crystal structures to study the effects of substitution of electron deficient fluoroalkyl chains on aromatics on packing modes, and weak noncovalent interactions that became the basis for the present chapter. We found that by fine-tuning the size of the aromatic core, lengthening perfluoroalkyl chain, altering the substitution position, and making use of these weak fluorous interactions, 1-D pi-pi stacking in these model compounds is achieved. This can provide us an opportunity to extend this concept to n-type solution processable air-stable organic semiconductor molecules which can be used in real world applications.

Tottempudi, Usha Kiran

150

Determination of gamma-hydroxybutyric acid in serum and urine by headspace solid-phase dynamic extraction combined with gas chromatography-positive chemical ionization mass spectrometry.  

PubMed

Gamma-hydroxybutyric acid is an emerging drug of abuse. Beside relaxation and euphoria it causes hypnosis and unconsciousness. Therefore the substance is misused as recreational drug and at drug-facilitated sexual assaults. An automated and effortless method for quantitation of gamma-hydroxybutyric acid in serum and urine was optimized and validated. Five hundred microliters sample volume are used for both matrices. The acid catalyzed conversion of gamma-hydroxybutyric acid to the corresponding gamma-butyrolactone is applied. Furthermore the method is based on headspace solid-phase dynamic extraction coupled with gas chromatography-mass spectrometry. The extraction process is performed by repeated aspiration and ejection of the headspace through a steel cannula which is coated on the inside with a polydimethylsiloxane sorbent. Thus absorption of analyte molecules by the sorbent is achieved. The influence of parameters as sorbent type, incubation temperature, number of extraction strokes, injection port temperature and injection flow speed on extraction recovery was investigated. The validation revealed good accuracy with a bias less than +/-5%. Intra- and interday precision determined at 10, 50 and 150 microg/ml for each matrix were in following ranges: 1.96-3.49% (intraday, serum), 2.38-4.31% (intraday, urine), 2.33-5.13% (interday, serum) and 2.53-5.64% (interday, urine). The method provided good linearity between 2 and 200 microg/ml yielding coefficients of determination R(2) > or = 0.9985. Limit of detection were determined at 0.16 microg/ml for serum and 0.17 microg/ml for urine, respectively. This method exhibits a fast, solvent-free and widely automated extraction process. It has been applied to toxicological routine analysis and therapeutic drug monitoring successfully. PMID:19327780

Lenz, Daniel; Kröner, Lars; Rothschild, Markus A

2009-05-01

151

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...

152

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

153

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

154

Use of Umbilical Cord Serum in Ophthalmology  

PubMed Central

Among blood preparations, serum has been topically used in the management of various ocular diseases in ophthalmology. Like peripheral blood serum, umbilical cord blood serum contains a high concentration of essential tear components, growth factors, neurotrophic factors, vitamin A, fibronectin, prealbumin, and oil. Umbilical cord serum can provide basic nutrients for epithelial renewal and can facilitate the proliferation, migration, and differentiation of the ocular surface epithelium. Eye drops made from umbilical cord serum have been applied to treat various ocular surface diseases, including severe dry eye with or without Sjögren's syndrome, ocular complications in graft-versus-host disease, persistent epithelial defects, neurotrophic keratopathy, recurrent corneal erosions, ocular chemical burn, and surface problems after corneal refractive surgery. Because mesenchymal stem cells from umbilical cord blood can be used to regenerate corneal tissue and retinal nerve cells, umbilical cord serum might be applied for tissue engineering and regenerative medicine in the future. PMID:25568842

2014-01-01

155

QUANTIFICATION OF FLUOROTELOMER-BASED CHEMICALS IN MAMMALIAN MATRICES BY MONITORING PERFLUOROALKYL CHAIN FRAGMENTS WITH GC/MS  

EPA Science Inventory

Perfluorocarboxylic acids (PFCAs), namely perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA), have been identified as persistent, bioaccurnulative and potentially toxic compounds. The structural analog, 8-2 fluorotelomer alcohol (8-2 FTOH) is considered the probable ...

156

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

157

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

158

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

159

Comparison of three types of mass spectrometers for HPLC/MS analysis of perfluoroalkylated substances and fluorotelomer alcohols.  

PubMed

The performance of three different types of mass spectrometers (MS) coupled to high performance liquid chromatography (HPLC) was compared for trace analysis of perfluoroalkylated substances (PFAS) and fluorotelomer alcohols (FTOHs). Ion trap MS in the full scan and product ion MS2 mode, time-of-flight (TOF) high resolution MS and quadrupole MS in the selected ion mode as well as triple quadrupole tandem MS were tested. Electrospray ionisation in the negative ion mode [ESI-] was best suited for all instruments and compounds. PFAS could only be separated by a buffered mobile phase, but the presence of buffer suppressed the ionisation of FTOHs. Therefore, two independent chromatographic methods were developed for the two compound classes. Mass spectra and product ion spectra obtained by in-source and collision induced dissociation fragmentation are discussed including ion adduct formation. Product ion yields of PFAS were only in the range of 0.3 to 12%, independent from the applied MS instrument. Ion trap MS2 gave product ion yields of 20 to 62% for FTOHs, whereas only 4.1 to 5.8% were obtained by triple quadrupole tandem MS. Ion trap MS was best suited for qualitative analysis and structure elucidation of branched isomeric structures of PFAS. Providing typical detection limits of 5 ng injected in MS2 mode, it was not sensitive enough for selective trace amount quantification. TOF high resolution MS was the only technique combining high selectivity and excellent sensitivity for PFAS analysis (detection limits of 2 to 10 pg), but lacked the possibility of MS-MS. Triple quadrupole tandem MS was the method of choice for quantification of FTOHs with detection limits in the low pg range. It is also well suited for the determination of PFAS, though its detection limits of 10 to 100 pg in tandem MS mode are about one order of magnitude higher than for TOF MS. PMID:15531790

Berger, Urs; Langlois, Ingrid; Oehme, Michael; Kallenborn, Roland

2004-01-01

160

Contribution of diffuse inputs to the aqueous mass load of perfluoroalkyl acids in river and stream catchments in Korea.  

PubMed

Recent studies disagree regarding the contributions of point versus non-point sources to the aqueous mass loads of perfluoroalkyl acids (PFAAs). This study investigated the longitudinal change in PFAA mass load from upstream to downstream stations along rivers and/or streams to assess the relative contributions of point versus nonpoint inputs. With concentrations 10 to 100 times higher than running water, point sources such as wastewater treatment plants (WWTPs) effluent and airport ditch-outlet (ADO) water were separated from neighboring upstream and downstream running waters using principal component analysis. Source waters were characterized by certain predominant components [e.g., perfluorobutylsulfonate (PFBS) and perfluorooctanoic acid (PFOA) in WWTP effluent and perfluorohexylsulfonate (PFHxS) and perfluorooctylsulfonate (PFOS) in ADO water], which were minor components of running water. From a mass balance assessment of PFAA mass load, certain compounds such as PFOA and PFBS dominated the contribution of point sources to the mass load in the running water at downstream stations or in small catchment basins with high levels of industrial activity. Most of the mass load in the investigated catchments was attributable to upstream running water with a minor influence from industrial, commercial, and domestic human activities. Furthermore, the negative relationship of per capita emission factors (hereafter, EFs) with population density and a lower contribution of PFAA from WWTPs (~30% on average) compared to the running water-derived mass load at the national level indicated that diffuse inputs were more important contributors to aqueous PFAA contamination in each catchment basin as well as the entire watershed of the country (Korea). Volatile precursor compounds, which are readily dispersed to neighboring basins and transformed to PFAAs in the ambient environment, can be an important source of these diffuse inputs and will become more significant over time. PMID:23849806

Kim, Seung-Kyu; Li, Dong-Hao; Shoeib, Mahiba; Zoh, Kyung-Duk

2014-02-01

161

Perfluoroalkyl substances and lipid concentrations in plasma during pregnancy among women in the Norwegian Mother and Child Cohort Study  

PubMed Central

Background Perfluoroalkyl substances (PFASs) are widespread and persistent environmental pollutants. Previous studies, primarily among non-pregnant individuals, suggest positive associations between PFAS levels and certain blood lipids. If there is a causal link between PFAS concentrations and elevated lipids during pregnancy, this may suggest a mechanism by which PFAS exposure leads to certain adverse pregnancy outcomes, including preeclampsia. Methods This cross-sectional analysis included 891 pregnant women enrolled in the Norwegian Mother and Child (MoBa) Cohort Study in 2003–2004. Non-fasting plasma samples were obtained at mid-pregnancy and analyzed for nineteen PFASs. Total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein cholesterol, and triglycerides were measured in plasma. Linear regression was used to quantify associations between each PFAS exposure and each lipid outcome. A multiple PFAS model was also fitted. Results Seven PFASs were quantifiable in >50% of samples. Perfluorooctane sulfonate (PFOS) concentration was associated with total cholesterol, which increased 4.2 mg/dL per interquartile shift (95% CI=0.8, 7.7) in adjusted models. Five of the seven PFASs studied were positively associated with HDL cholesterol, and all seven had elevated HDL associated with the highest quartile of exposure. Perfluoroundecanoic acid showed the strongest association with HDL: HDL increased 3.7 mg/dL per interquartile shift (95% CI=2.5, 4.9). Conclusion Plasma concentrations of PFASs were positively associated with HDL cholesterol, and PFOS was positively associated with total cholesterol in this sample of pregnant Norwegian women. While elevated HDL is not an adverse outcome per se, elevated total cholesterol associated with PFASs during pregnancy could be of concern if causal. PMID:24189199

Starling, Anne P.; Engel, Stephanie M.; Whitworth, Kristina W.; Richardson, David B.; Stuebe, Alison M.; Daniels, Julie L.; Haug, Line Småstuen; Eggesbø, Merete; Becher, Georg; Sabaredzovic, Azemira; Thomsen, Cathrine; Wilson, Ralph E.; Travlos, Gregory S.; Hoppin, Jane A.; Baird, Donna D.; Longnecker, Matthew P.

2013-01-01

162

Perfluoroalkyl compounds in dust from Asian, Australian, European, and North American homes and UK cars, classrooms, and offices.  

PubMed

Perfluoroalkyl compounds (PFCs) were measured in dust from Australian, Canadian, French, German, Kazahkstani, Thai, UK, and US homes, and UK cars, classrooms, and offices. Most PFCs were significantly lower in Kazahkstan and Thailand than elsewhere; 2-(N-methylperfluoro-1-octanesulfonamido)-ethanol (MeFOSE) and 2-(N-ethylperfluoro-1-octanesulfonamido)-ethanol (EtFOSE) were significantly lower in Canada than in the UK and the US; perfluoro-1-hexanesulfonate (PFHxS) was significantly lower in Canada than in the UK, and N-ethylperfluoro-1-octanesulfonamide (EtFOSA) was significantly higher in Australia than in the UK. High EtFOSA concentrations in some samples may be consistent with its use as an insecticide. Perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), PFHxS, and MeFOSE were significantly higher in classrooms than in cars, homes, and offices; N-methylperfluoro-1-octanesulfonamide (MeFOSA) was significantly lower in classrooms than in homes and offices, and perfluoro-1-octanesulfonamide (FOSA) was significantly lower in classrooms than in cars, homes, and offices. While homes are usually the most important vector of dust exposure (typically > 60%), offices and classrooms make important contributions. While diet is usually the main exposure pathway for UK adults and children (~1-6 years) for PFOS, PFOA, and PFHxS; dust ingestion can be significant under high dust ingestion scenarios. Even under high-end exposure scenarios for dust and diet, PFOS and PFOA exposures are well within the European Food Safety Authority tolerable daily intakes. PMID:20810169

Goosey, Emma; Harrad, Stuart

2011-01-01

163

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...

164

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

165

Perfluoroalkyl substances in polar bear mother-cub pairs: a comparative study based on plasma levels from 1998 and 2008.  

PubMed

Perfluoroalkyl substances (PFASs) are protein-binding blood-accumulating contaminants that may have detrimental toxicological effects on the early phases of mammalian development. To enable an evaluation of the potential health risks of PFAS exposure for polar bears (Ursus maritimus), an exposure assessment was made by examining plasma levels of PFASs in polar bear mothers in relation to their suckling cubs-of-the-year (~4 months old). Samples were collected at Svalbard in 1998 and 2008, and we investigated the between-year differences in levels of PFASs. Seven perfluorinated carboxylic acids (??PFCAs: PFHpA, PFOA, PFNA, PFDA, PFUnDA, PFDoDA, and PFTrDA) and two perfluorinated sulfonic acids (??PFSAs: PFHxS and PFOS) were detected in the majority of the mothers and cubs from both years. In mothers and cubs, most PFCAs were detected in higher concentrations in 2008 than in 1998. On the contrary, levels of PFOS were lower in 2008 than in 1998, while levels of PFHxS did not differ between the two sampling years. PFOS was the dominating compound in mothers and cubs both in 1998 and in 2008. Concentration of PFHpA did not differ between mothers and cubs, while concentrations of PFOA, PFNA, PFDA, PFUnDA, PFDoDA, PFTrDA, PFHxS, and PFOS were higher in mothers than in their cubs. Except from PFHpA, all compounds correlated significantly between mothers and their cubs. The mean cub to mother ratios ranged from 0.15 for PFNA to 1.69 for PFHpA. On average (mean±standard error of mean), the levels of ??PFCAs and ??PFSAs in cubs were 0.24±0.01 and 0.22±0.01 times the levels in their mothers, respectively. Although maternal transfer appears to be a substantial source of exposure for the cubs, the low cub to mother ratios indicate that maternal transfer of PFASs in polar bears is relatively low in comparison with hydrophobic contaminants (e.g. PCBs). Because the level of several PFASs in mothers and cubs from both sampling years exceeded the levels associated with health effects in humans, our findings raise concern on the potential health effects of PFASs in polar bears from Svalbard. Effort should be made to examine the potential health effects of PFASs in polar bears. PMID:23010253

Bytingsvik, Jenny; van Leeuwen, Stefan P J; Hamers, Timo; Swart, Kees; Aars, Jon; Lie, Elisabeth; Nilsen, Else Mari Espseth; Wiig, Oystein; Derocher, Andrew E; Jenssen, Bjørn M

2012-11-15

166

Serum-free Media for Culturing and Serial-Passaging of Adult Human Retinal Pigment Epithelium  

Microsoft Academic Search

The ability of a chemically-defined serum-free culture medium to support the attachment, growth and serial passaging of primary adult human retinal pigment epithelial (RPE) cells was studied. Primary cultures of adult human RPE were established in a chemically-defined serum-free culture medium on both bare or bovine corneal endothelial extracellular matrix-coated tissue-culture plastic. Confluent cells were serially passaged in chemically-defined serum-free

TONGALP H. TEZEL; LUCIAN V. DEL PRIORE

1998-01-01

167

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

168

[Serum antioxidative activity].  

PubMed

Model systems used in the determination of serum antioxidative activity (AOA), which differ both in the way of generating free radicals and in the mode of their detection, are clinically analyzed. The specific features and potentialities of the model systems developed at the authors' laboratory are characterized. These included yolk lipoprotein suspensions, liposomal suspensions formed from total phospholipid fraction, the hemoglobin-hydrogen peroxide-luminol system. The investigations show that most model systems for determining serum AOA contribute to the water soluble interceptors of free radicals (ascorbate, urate, plasma proteins, etc.), chelating and oxidative agents of catalytically active Fe2+ (ceruloplasmin, transferrin, albumin, etc.). The serum AOA levels measured with different model systems vary with the body's status. To determine serum AOA and the contribution of major endogenous antioxidants and inhibitors of free radical reactions may be a basis for the goal-oriented use of exogenous antioxidants in the therapy of a great variety of diseases. PMID:10204018

Klebanov, G I; Teselkin, Iu O; Babenkova, I V; Liubitski?, O B; Vladimirov, Iu A

1999-01-01

169

Hematology and serum chemistry values of juvenile and adult ruffed lemurs (Varecia variegata).  

PubMed

Hematologic and serum chemistry values are presented for adult and juvenile red ruffed lemurs (Varecia variegata rubra) and black and white ruffed lemurs (Varecia variegata variegata) maintained in a zoological collection. Hematologic and serum chemical values are compared between age groups and subspecies and with other primate species. Elevated hematocrit, total protein, and serum albumin values were noted. Significant differences in cholesterol, total protein, and serum albumin values between the two age groups are discussed. PMID:3981623

Karesh, W B; Olson, T P

1985-01-01

170

SURFACE TENSION OF SERUM  

PubMed Central

A technique is described for the study of the adsorption in function of the time of molecules of colloidal substances in the surface layer of water. This technique eliminates previous causes of error, in particular the individual coefficient. The curves obtained by plotting the data for serum at various dilutions give a clear picture of the phenomenon, and show that the low values of the initial surface tension of pure serum and serum at low dilutions are due to the extreme rapidity of adsorption of the molecules in the surface layer, owing to their high concentration. Evidence is given that colloidal substances in solution substantially lower the surface tension of the solvent, even when they are in too small a number to form an homogeneous monolayer. PMID:19869018

du Noüy, P. Lecomte

1925-01-01

171

Orthogonal zirconium diol/C18 liquid chromatography-tandem mass spectrometry analysis of poly and perfluoroalkyl substances in landfill leachate.  

PubMed

Leachates coming from landfills contain a myriad of compounds of potential environmental and human health concern, including per- and polyfluorinated alkyl substances (PFASs). Micro liquid-liquid extraction was combined with a 900?l large volume injection (LVI) for the analysis of 70 PFASs in landfill leachate by orthogonal LC-MS/MS. The LVI approach introduced 7 times more extract than conventional injection approaches. Two zirconium-modified diol guard columns effectively retained PFASs from the organic leachate extract and an analytical C18 column was used for separation. Method accuracy and precision for PFASs with analytical grade reference materials ranged from 81-120% and 5.5-33%, respectively. Estimated method detection limits in the low to sub-ng/L. Seven landfill leachates were analyzed by the optimized analytical method for the purposes of method demonstration. Leachates were characterized by a wide variety of PFASs, reporting on 36 previously-unanalyzed PFASs in leachate. Perfluoroalkyl carboxylates were the most abundant class detected while phosphorous-containing PFASs, present in all leachates, were at low concentrations. The 3-perfluoropentyl propanoate (5:3 FTCA) was the most concentrated analyte in most samples and constitutes a previously unreported but significant component of landfill leachate. PMID:25103279

Allred, B McKay; Lang, Johnsie R; Barlaz, Morton A; Field, Jennifer A

2014-09-12

172

Estimation of the acid dissociation constant of perfluoroalkyl carboxylic acids through an experimental investigation of their water-to-air transport.  

PubMed

The acid dissociation constants (pKas) of perfluoroalkyl carboxylic acids (PFCAs) have been the subject of discussion in the literature; for example, values from -0.2 to 3.8 have been suggested for perfluorooctanoic acid (PFOA). The dissociated anionic conjugate bases of PFCAs have negligible air-water partition coefficients (KAWs) and do not volatilize from water. The neutral acids, however, have relatively high KAWs and volatilization from water has been demonstrated. The extent of volatilization of PFCAs in the environment will depend on the water pH and their pKa. Knowledge of the pKas of PFCAs is therefore vital for understanding their environmental transport and fate. We investigated the water-to-air transfer of PFCAs in a novel experimental setup. We used ?1 ?g L(-1) of PFCAs in water (above environmental background concentrations but below the concentration at which self-association occurs) at different water pH (pH 0.3 to pH 6.9) and sampled the PFCAs volatilized from water during a 2-day experiment. Our results suggest that the pKas of C4-11 PFCAs are <1.6. For PFOA, we derived a pKa of 0.5 from fitting the experimental measurements with a volatilization model. Perfluoroalkane sulfonic acids were not volatilized, suggesting that their pKas are below the investigated pH range (pKa <0.3). PMID:23952814

Vierke, Lena; Berger, Urs; Cousins, Ian T

2013-10-01

173

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

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

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

176

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.

177

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

178

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

179

Validation of a screening method based on liquid chromatography coupled to high-resolution mass spectrometry for analysis of perfluoroalkylated substances in biota.  

PubMed

A screening method for analysis of perfluoroalkylated substances (PFAS) in biota samples has been developed and validated using liver samples from polar cod (Boreogadus saida) and glaucous gull (Larus hyperboreus). The method was based on extraction of target compounds from homogenised samples into the solvent mixture used as mobile phase in high-performance liquid chromatography (HPLC), i.e. methanol/water (50:50; 2 mM ammonium acetate). The extract was filtered and directly injected into a HPLC/time-of-flight mass spectrometry (TOF-MS) system. Quantification was performed using 7H-perfluoroheptanoic acid as internal standard and a calibration standard solution dissolved in sample extract for each matrix type (matrix-matched calibration standard). The method is very time and cost efficient. Except for long-chain compounds and perfluorooctane sulfonamide (which cannot be covered by this method), recoveries were between 60% and 115% and method detection limits were in the range 0.04-1.3 ng/g wet weight. Blank values could be neglected with the exception of perfluorooctane sulfonate (PFOS), perfluorohexanoic acid (PFHxA) and perfluorooctanoic acid (PFOA). One of the major challenges in PFAS analysis is ionisation disturbance by co-eluting matrix in the ion source of the mass spectrometer. Both matrix and analyte specific signal enhancement and suppression was observed and quantified. Repeated extractions (n = 3) gave relative standard deviations (RSD) <35% for all PFAS. Accuracy was examined by comparing the screening method to the generally applied ion pair extraction (IPE) method. PFAS concentration values of a glaucous gull liver sample deviated by less than 30% for the two methods, provided that matrix-matched calibration standards were employed in both methods. PMID:16038211

Berger, Urs; Haukås, Marianne

2005-07-22

180

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; Osterås, Ann-Helen

2014-09-24

181

Circulating serum xenoestrogens and mammographic breast density  

PubMed Central

Introduction Humans are widely exposed to estrogenically active phthalates, parabens, and phenols, raising concerns about potential effects on breast tissue and breast cancer risk. We sought to determine the association of circulating serum levels of these chemicals (reflecting recent exposure) with mammographic breast density (a marker of breast cancer risk). Methods We recruited postmenopausal women aged 55 to 70 years from mammography clinics in Madison, Wisconsin (N = 264). Subjects completed a questionnaire and provided a blood sample that was analyzed for mono-ethyl phthalate, mono-butyl phthalate, mono-benzyl phthalate, butyl paraben, propyl paraben, octylphenol, nonylphenol, and bisphenol A (BPA). Percentage breast density was measured from mammograms by using a computer-assisted thresholding method. Results Serum BPA was positively associated with mammographic breast density after adjusting for age, body mass index, and other potentially confounding factors. Mean percentage density was 12.6% (95% confidence interval (CI), 11.4 to 14.0) among the 193 women with nondetectable BPA levels, 13.7% (95% CI, 10.7 to 17.1) among the 35 women with detectable levels below the median (<0.55 ng/ml), and 17.6% (95% CI, 14.1 to 21.5) among the 34 women with detectable levels above the median (>0.55 ng/ml; Ptrend = 0.01). Percentage breast density was also elevated (18.2%; 95% CI, 13.4 to 23.7) among the 18 women with serum mono-ethyl phthalate above the median detected level (>3.77 ng/ml) compared with women with nondetectable BPA levels (13.1%; 95% CI, 11.9 to 14.3; Ptrend = 0.07). No other chemicals demonstrated associations with percentage breast density. Conclusions Postmenopausal women with high serum levels of BPA and mono-ethyl phthalate had elevated breast density. Further investigation of the impact of BPA and mono-ethyl phthalate on breast cancer risk by using repeated serum measurements or other markers of xenoestrogen exposure are needed. PMID:23710608

2013-01-01

182

Development and evaluation of a mechanistic bioconcentration model for ionogenic organic chemicals in fish.  

PubMed

A mechanistic mass balance bioconcentration model is developed and parameterized for ionogenic organic chemicals (IOCs) in fish and evaluated against a compilation of empirical bioconcentration factors (BCFs). The model is subsequently applied to a set of perfluoroalkyl acids. Key aspects of model development include revised methods to estimate the chemical absorption efficiency of IOCs at the respiratory surface (E(W) ) and the use of distribution ratios to characterize the overall sorption capacity of the organism. Membrane-water distribution ratios (D(MW) ) are used to characterize sorption to phospholipids instead of only considering the octanol-water distribution ratio (D(OW) ). Modeled BCFs are well correlated with the observations (e.g., r(2) ?= 0.68 and 0.75 for organic acids and bases, respectively) and accurate to within a factor of three on average. Model prediction errors appear to be largely the result of uncertainties in the biotransformation rate constant (k(M) ) estimates and the generic approaches for estimating sorption capacity (e.g., D(MW) ). Model performance for the set of perfluoroalkyl acids considered is highly dependent on the input parameters describing hydrophobicity (i.e., log K(OW) of the neutral form). The model applications broadly support the hypothesis that phospholipids contribute substantially to the sorption capacity of fish, particularly for compounds that exhibit a high degree of ionization at biologically relevant pH. Additional empirical data on biotransformation and sorption to phospholipids and subsequent incorporation into property estimation approaches (e.g., k(M) , D(MW) ) are priorities with respect to improving model performance. PMID:23023933

Armitage, James M; Arnot, Jon A; Wania, Frank; Mackay, Don

2013-01-01

183

Serum ferritin in thyroid cancer.  

PubMed

Serum ferritin, one of the nonspecific tumor markers, was studied in 102 thyroid cancer patients, who had been thyroidectomized and were off thyroxine for 1 month, making them hypothyroid. Serum ferritin in thyroid cancer patients was not significantly different as compared to controls. Nevertheless, high levels of serum ferritin were observed in the thyroid cancer group as compared to primary hypothyroid patients. Furthermore, there was a significant difference in serum ferritin between thyroid cancer patients without metastasis and those with metastasis, patients with metastasis showing higher levels. Classification of thyroid cancer patients into different histological types revealed higher ferritin levels in follicular carcinoma as compared to papillary carcinoma. These data suggest that, although serum ferritin may not be a tumor marker for thyroid cancer, this parameter seems to be sensitive to the presence of metastasis and the histologic diagnosis. PMID:8118224

Deshpande, U R; Nadkarni, G D; Samuel, A M

1993-01-01

184

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

185

Serum albumin alters the expression of iron-controlled genes in Pseudomonas aeruginosa.  

PubMed

Pseudomonas aeruginosa, which causes serious infections in immunocompromised patients, produces numerous virulence factors, including exotoxin A and the siderophore pyoverdine. As production of these virulence factors is influenced by the host environment, we examined the effect serum has on global transcription within P. aeruginosa strain PAO1 at different phases of growth in an iron-deficient medium. At early exponential phase, serum significantly enhanced expression of 138 genes, most of which are repressed by iron, including pvdS, regA and the pyoverdine synthesis genes. However, serum did not interfere with the repression of these genes by iron. Serum enhanced regA expression in a fur mutant of PAO1 but not in a pvdS mutant. The serum iron-binding protein apotransferrin, but not ferritin, enhanced regA and pvdS expression. However, in PAO1 grown in a chemically defined medium that contains no iron, serum but not apotransferrin enhanced pvdS and regA expression. While complement inactivation failed to eliminate this effect, albumin absorption reduced the effect of serum on pvdS and regA expression in the iron-deficient medium chelexed tryptic soy broth dialysate. Additionally, albumin absorption eliminated the effect of serum on pvdS and regA expression in the chemically defined medium. These results suggest that serum enhances the expression of P. aeruginosa iron-controlled genes by two mechanisms: one through apotransferrin and another one through albumin. PMID:22053004

Kruczek, Cassandra; Wachtel, Mitchell; Alabady, Magdy S; Payton, Paxton R; Colmer-Hamood, Jane A; Hamood, Abdul N

2012-02-01

186

FACTORS CONTROLLING SERUM ?-GLOBULIN CONCENTRATION  

PubMed Central

Both synthetic and catabolic processes determine the serum ?-globulin level. The rate of ?-globulin synthesis appears to be the primary factor determining the amount of serum ?-globulin. Increase of ?-globulin synthesis (as may occur following immunization or development of plasma cell tumor) elevates the serum ?-globulin level. This, in turn, accelerates the fractional rate of ?-globulin catabolism. The change in catabolic rate reduces the dimensions of the serum change from that which would occur if synthesis alone determined the serum ?-globulin level. The present studies indicate the existence of a homeostatic mechanism controlling the rate of ?-globulin catabolism. The mechanisms of ?-globulin catabolism are specific and selective. Marked serum increase of other immunoglobulin components (?2A-globulins and ?1-macroglobulins) do not accelerate ?-globulin catabolism. Similarly, serum albumin increases do not influence ?-globulin catabolism. The site determining ?-globulin catabolism is restricted to a part of the ?-globulin molecule; i.e., on the F piece obtained by papain digestion and, by inference, on the H chains obtained by reduction and alkylation of ?-globulin molecules. PMID:14087625

Fahey, John L.; Robinson, Alan G.

1963-01-01

187

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

188

Serum chemistry of the minke whale from the northeastern Atlantic.  

PubMed

Serum samples were collected from 42 harpooned minke whales (Balaenoptera acutorostrata) during commercial whaling off the coast of northern Norway (1997 and 1998) and analyzed for serum chemistry parameters in order to find clinical reference values for the northeastern Atlantic stock of this species. Mean and median values, as well as standard deviation and 90% central range, are presented for 28 different serum chemistry parameters. Lipemia is a common finding in marine mammals such as the minke whale, and chemical analysis of lipemic serum samples may produce artifacts. We found statistically significant elevated values of total protein, globulin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), sodium and chloride in strongly-lipemic compared to non-lipemic samples, all which may be artifacts due to interference of lipids with the methods used for analysis. In addition, we found significantly elevated levels of creatin kinase, lactate dehydrogenase (LDH), urea, uric acid and triglycerides, as well as a decrease in creatinine in the strongly lipemic samples. Reanalyzing serum samples after twelve mo storage at -20 C (n = 13) revealed reduction in the serum concentration of the enzymes ALT (42%), alkaline phosphatase (ALP; 10%), LDH (19%), gamma glutamyl transferase (17%) and amylase (11%), as well as for triglycerides (9%) and non-esterified fatty acids (16%). It is crucial that serum chemistry analysis is performed without delay after sampling. Possible changes in the values of some parameters due to the presence of high amounts of lipids or long term storage of samples must be considered when interpreting results from serum chemistry analysis in these animals. PMID:11310885

Tryland, M; Brun, E

2001-04-01

189

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, Kåre; Moritz, Thomas; Nilsson, Lars-Göran; Nyberg, Lars

2014-01-01

190

Serum therapy for Cryptococcal meningitis.  

PubMed

Three patients were treated with combined amphotericin B and rabbit anticryptococcal antibody in the 1960s. Rabbit antibody was administered intravenously and was well tolerated. For each patient, administration of rabbit antibody resulted in the appearance of serum Cryptococcus neoformans agglutinins. For two patients the administration of rabbit antibody resulted in negative serum latex tests for cryptococcal antigen. This limited experience with adjunctive antibody therapy provides valuable precedents if antibody therapy is used again for treatment of human cryptococcosis. PMID:8749638

Gordon, M A; Casadevall, A

1995-12-01

191

Radioimmunoassay of Human Serum Thyrotrophin  

Microsoft Academic Search

The double antibody radioimmunoassay of serum thyroid-stimulating hormone (TSH) allows measurement of circulating levels of the hormone in most normal subjects. The serum TSH level in normal subjects is 1·6 ± 0·8?U\\/ml. Patients with non-toxic goitre and acromegaly have normal TSH levels. Values are always raised in hypothyroid patients (with primary thyroid disease) and are significantly lowered in those with

Reginald Hall; Jacqueline Amos; Brian J. Ormston

1971-01-01

192

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

193

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

194

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

195

ON THE EQUILIBRIUM CONDITION BETWEEN BLOOD SERUM AND SEROUS CAVITY FLUIDS.  

PubMed

1. Comparative studies of blood serum and edema fluid from the same individual indicate that, regardless of the pathological condition present, whether the fluid be "transudate" or "exudate," certain definite qualitative chemical relations obtain. 2. The chief feature of these relations is that the edema fluid contains more Cl and less K than the blood serum; while the Na, HCO(3), Ca, urea, glucose, and non-protein nitrogen exist in approximately the same concentrations in the serum and in the edema fluid. The freezing point is also the same in both fluids, while the specific conductivity is constantly higher in the edema fluid. 3. The above mentioned variations between the edema fluid and the serum appear to be related to the difference in the concentration of protein in the two solutions. 4. The relationships between blood serum and edema fluid seem to result from a simple membrane equilibrium, influenced in part by the proteins present. PMID:19871958

Loeb, R F; Atchley, D W; Palmer, W W

1922-05-20

196

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.

197

Serum Sclerostin Levels Vary With Season  

PubMed Central

Context: To establish the clinical utility of serum sclerostin levels, it is important to know whether there is seasonal variation in the measurements. Objective: This study was done to determine whether serum sclerostin levels vary by season in healthy older men and women. Methods: Serum sclerostin levels were measured in archived serum of 314 healthy men and women aged 65 years and older and examined for seasonal variation. Several factors known to vary by season and previously reported to be associated with serum sclerostin levels, including serum osteocalcin, physical activity, and serum PTH levels, were also measured in these subjects. Sex did not modify the association of season with sclerostin, so the men and women were analyzed together. Results: Serum sclerostin levels varied significantly by season (P < .001, after adjustment for sex). Sclerostin levels in the wintertime were 20% higher than the all-year mean, the levels gradually declined through the spring and summer, and by the fall, they were 20% below the all-year mean. Adjustment for serum osteocalcin, physical activity, and serum PTH did not alter the seasonal means. Seasonal differences in serum osteocalcin, physical activity, and serum PTH were not statistically significant. Conclusions: This study documents marked seasonal variation in serum sclerostin levels. It is important to recognize this source of biological variability when considering the potential clinical utility of sclerostin measurements. PMID:24248178

Harris, Susan S.; Ceglia, Lisa; Palermo, Nancy J.

2014-01-01

198

Serum alpha 1 antitrypsin and pulmonary emphysema.  

PubMed

Using isoelectric focusing (IEF) and radial immunodiffusion (RID) techniques, serum samples from 100 normal healthy adults and 21 patients with pulmonary emphysema were analysed to identify various alpha 1 antitrypsin phenotypes and the serum concentrations. Ten percent of the patients had low serum values. The normal or most common genetic form, MM, is the predominant phenotype in both controls and patients. PMID:8961698

Shahid, A; Siddiqui, A A; Aziz, S; Ansari, M; Zuberi, S J; Waqar, M A

1996-05-01

199

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

2012-12-07

200

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 ...

201

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 ...

202

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

203

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

204

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

205

The dietary acrylamide intake adversely affects the serum trace element status.  

PubMed

Acrylamide is an organic chemical which occurs in foods widespreadly consumed in diets worldwide. The purpose of this study was to evaluate the serum trace element levels (Fe, Cu, Zn, Mn, Cr, Se, Co, Ni, V, As, Mg, P, Li, K, Al) in Wistar rats exposed to acrylamide. Acrylamide was administered to the treatment groups at 2 and 5 mg/kg body weight (bw)/day via drinking water for 90 days. Inductively coupled plasma mass spectrometry was used for the determination of serum trace element concentrations. Serum Zn, Se, Co, V and Mg concentrations of 5 mg/kg bw/day acrylamide-treated male rats were lower, whereas serum As concentration was higher than the same parameters of the controls rats. Similarly, serum Zn, Se, Co, V and Mg concentrations were decreased in 5 mg/kg bw/day acrylamide-treated female rats compared with control rats. On the other hand, there were no significant differences between serum Fe, Cu, Mn, Cr, Ni, P, Li, K and Al concentrations of all groups. The results from this study provide evidence that dietary acrylamide intake adversely affects the serum trace elements status. PMID:23306945

Yerlikaya, Fatma Hümeyra; Yener, Ye?im

2013-04-01

206

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.

Carpi, Anthony

2003-03-27

207

SERUM LIPID PROFILE IN SUICIDE ATTEMPTERS  

PubMed Central

Practical difficulties associated with assessment of central parameters necessitates the development of peripheral markers of suicidal risk. Recent research suggest that serum lipid profile may be a useful indicator of suicidal behaviour. Serum lipid profiles of forty suicide attempters were compared with forty age, sex and BMI matched controls. Total serum cholesterol, serum Triglyceride, LDL levels and HDL levels were found to be lower in suicide attempters but were not statistically significant. Statistically significant negative con-elation was seen between risk-rescue score and above mentioned parameters. No statitically significant difference was observed when various diagnostic break-up groups of patients were compared. PMID:21430801

Verma, Sandeep; Trivedi, J.K.; Singh, H.; Dalal, P.K.; Asthana, O.P.; Srivastava, J.S.; Mishra, Rakesh; Ramakant; Sinha, P.K.

1999-01-01

208

Comparative study of modifications produced by x rays in bovine serum proteins  

Microsoft Academic Search

Serum albumin and gamma globulin appear to be more radiosensitive than ; alpha and BETA globulins. Small irradiation doses are sufficient to ; chemically modify certain sites in these proteins without producing very serious ; modifications in the secondary and tertiary structures. Such modifications ; contribute to the understanding of the differences in the physiological, and in ; particular antigen

J. L. Azanza; A. Ducastaing; J. Raymond; P. Creach

1972-01-01

209

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

210

Adsorption of human serum albumin: Dependence on molecular architecture of the oppositely charged surface  

Microsoft Academic Search

We contrast the adsorption of human serum albumin (HSA) onto two solid substrates previously primed with the same polyelectrolyte of net opposite charge to form one of two alternative structures: randomly adsorbed polymer and the ``brush'' configuration. These structures were formed either by the adsorption of quaternized poly-4-vinylpyridine (QPVP) or by end-grafting QPVP chains of the same chemical makeup and

Svetlana A. Sukhishvili; Steve Granick

1999-01-01

211

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.

212

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

213

Serum prolidase activity in psoriasis patients.  

PubMed

This study aimed to evaluate serum prolidase activity and the effects of gender, body mass index (BMI), disease severity and duration, and therapy type on prolidase activity in patients with psoriatic as well as the relationship between serum NO· and prolidase levels in these patients. The study included 29 clinically documented plaque patients with psoriasis and 24 healthy volunteers. Data such as age, sex, BMI, duration and severity of disease, and type of therapy were assessed. NO· levels were determined by the Griess reaction. Serum prolidase assay is based on a colorimetric determination of proline by Chinard's reagent. We did not determine any difference in serum NO· levels of psoriatic patients when compared to controls. Serum prolidase levels in psoriasis patients were significantly higher than those in controls. There was no significant difference in prolidase activity between male and female. No statistically significant correlations were found between serum prolidase levels and BMI, PASI and disease duration. When compared between topical treatment group and systemic treatment group, there was no significant difference in serum prolidase activity. In conclusion, patients with psoriasis exhibit higher serum prolidase activity independent of gender, BMI, disease severity or duration, type of treatments or NO· level. However, further studies are needed to verify these findings as well as altered collagen synthesis in patients with psoriasis. PMID:23553128

Guven, Berrak; Can, Murat; Genc, Mehmet; Koca, Rafet

2013-08-01

214

Serum Glutamic Oxalacetic Transaminase Content in Hypothermia  

Microsoft Academic Search

When the body temperature of pentobarbitalized dogs was lowered, by surface-immersion technique, to 27 degrees -26 degrees C, elevations in serum glutamic oxalacetic transaminase were found only after a period of prolonged hypothermia (12 hours). When the animals were rewarmed, serum levels returned to normal. Histologic study of organs rich in glutamic oxalacetic transaminase revealed no necrosis. The cause for

Emil Blair; Robert Hook; Howard Tolley; G. Edwin Bunce

1961-01-01

215

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

216

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

217

Autologous serum for ocular surface diseases.  

PubMed

Autologous serum has been used to treat dry eye syndrome for many years. It contains several growth factors, vitamins, fibronectin and other components that have been considered important for corneal and conjunctival integrity. Serum eye drops are usually prepared as an unpreserved blood solution. The serum is by nature well tolerated and its biochemical properties are somewhat similar to natural tears. Autologous serum eye drops have been reported to be effective for the treatment of severe dry eye-related ocular surface disorders (Sjögren's syndrome), and also other entities such as superior limbic keratoconjunctivitis, graft-versus-host disease, Stevens-Johnson syndrome, ocular cicatricial pemphigoid, recurrent or persistent corneal erosions, neurotrophic keratopathy, Mooren's ulcer, aniridic keratopathy, filtering blebs after trabeculectomy, and post-keratorefractive surgery. The purpose of this study is to review the recently published literature on ocular surface diseases treated with human autologous serum eye drops. PMID:19274411

Quinto, Guilherme Goulart; Campos, Mauro; Behrens, Ashley

2008-01-01

218

Methodological aspects of a national population-based study of persistent organochlorine compounds in serum.  

PubMed

Key methodological aspects are presented for a study of concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and organochlorine pesticides in the serum of a sample of the New Zealand population aged 15 years and older. The study took advantage of the sampling frame and sample collection and interview processes of the National Nutrition Study (NNS). An additional blood sample for this organochlorines study was collected by the NNS and questions added to the NNS questionnaire. Serum was obtained from the blood and, based on responses to questions in the questionnaire, samples with possible occupational exposure to organochlorines were excluded. Remaining samples providing at least 2 ml of serum were pooled within 80 strata defined according to geographic area, age group, sex and ethnicity. A minimum number of five individual serum samples was required for pooling within a stratum. Within strata with sufficient samples, two or three pooled samples were created for variance calculation. Eligible for inclusion in the study were 2497 individual serum samples. Sixty strata had sufficient serum samples for pooling and chemical analysis. This was the first study of organochlorine compounds with a national population-based sample. Two factors that made the study feasible deserve emphasis. First, being able to "piggy-back" on another study. Second, pooling of samples to reduce analytic expenses. It is hoped that the methods used in this study will form the basis for other studies investigating organochlorine concentrations in national populations. PMID:15639266

Bates, Michael N; Buckland, Simon J; Garrett, Nick; Caudill, Samuel P; Ellis, Howard

2005-02-01

219

Effects of Transport Stress on Serum Alkaline Phosphatase Activity in Beagle Dogs  

PubMed Central

Here, to determine the effects of transport stress on blood parameters in dogs, we investigated the changes in hematologic and serum chemical parameters in healthy beagle dogs transported from Beijing, China, to Osaka, Japan, to obtain the background data. Only the activity of serum alkaline phosphatase increased clearly upon arrival, a change attributed to transport stress, but the activity gradually reduced afterward. No marked changes in levels of other blood parameters were noted. Our findings here suggest that alkaline phosphatase is a useful tool for studying transport stress. PMID:24172197

Ochi, Takehiro; Nishiura, Ippei; Tatsumi, Mitsuyoshi; Hirano, Yoshimi; Yahagi, Kouichi; Sakurai, Yasuhiro; Sudo, Yuji; Koyama, Hironari; Hagita, Yuichi; Fujimoto, Yoshikatsu; Kitamura, Shinji; Hashimoto, Hideki; Nakamura, Tomoya; Yamada, Asobi; Tanimoto, Masayoshi; Nishina, Noriko

2013-01-01

220

Vibrio cholerae interactions with Mytilus galloprovincialis hemocytes mediated by serum components  

PubMed Central

Edible bivalves (e.g., mussels, oysters) can accumulate large amount of bacteria in their tissues and act as passive carriers of pathogens to humans. Bacterial persistence inside bivalves depends, at least in part, on hemolymph anti-bacterial activity that is exerted by both serum soluble factors and phagocytic cells (i.e., the hemocytes). It was previously shown that Mytilus galloprovincialis hemolymph serum contains opsonins that mediate D-mannose-sensitive interactions between hemocytes and Vibrio cholerae O1 El Tor bacteria that carry the mannose-sensitive hemagglutinin (MSHA). These opsonins enhance phagocytosis and killing of vibrios by facilitating their binding to hemocytes. Since V. cholerae strains not carrying the MSHA ligand (O1 classical, non-O1/O139) are present in coastal water and can be entrapped by mussels, we studied whether in mussel serum, in addition to opsonins directed toward MSHA, other components can mediate opsonization of these bacteria. By comparing interactions of O1 classical and non-O1/O139 strains with hemocytes in artificial sea water and serum, it was found that M. galloprovincialis serum contains components that increase by at approximately twofold their adhesion to, association with, and killing by hemocytes. Experiments conducted with high and low molecular mass fractions obtained by serum ultrafiltration indicated that these compounds have molecular mass higher than 5000 Da. Serum exposure to high temperature (80°C) abolished its opsonizing capability suggesting that the involved serum active components are of protein nature. Further studies are needed to define the chemical properties and specificity of both the involved bacterial ligands and hemolymph opsonins. This information will be central not only to better understand V. cholerae ecology, but also to improve current bivalve depuration practices and properly protect human health. PMID:24367358

Canesi, Laura; Pezzati, Elisabetta; Stauder, Monica; Grande, Chiara; Bavestrello, Margherita; Papetti, Adele; Vezzulli, Luigi; Pruzzo, Carla

2013-01-01

221

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

222

Cathepsin-L Can Resist Lysis by Human Serum in Trypanosoma brucei brucei  

PubMed Central

Closely related African trypanosomes cause lethal diseases but display distinct host ranges. Specifically, Trypanosoma brucei brucei causes nagana in livestock but fails to infect humans, while Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense cause sleeping sickness in humans. T. b. brucei fails to infect humans because it is sensitive to innate immune complexes found in normal human serum known as trypanolytic factor (TLF) 1 and 2; the lytic component is apolipoprotein-L1 in both TLFs. TLF resistance mechanisms of T. b. gambiense and T. b. rhodesiense are now known to arise through either gain or loss-of-function, but our understanding of factors that render T. b. brucei susceptible to lysis by human serum remains incomplete. We conducted a genome-scale RNA interference (RNAi) library screen for reduced sensitivity to human serum. Among only four high-confidence ‘hits’ were all three genes previously shown to sensitize T. b. brucei to human serum, the haptoglobin-haemoglobin receptor (HpHbR), inhibitor of cysteine peptidase (ICP) and the lysosomal protein, p67, thereby demonstrating the pivotal roles these factors play. The fourth gene identified encodes a predicted protein with eleven trans-membrane domains. Using chemical and genetic approaches, we show that ICP sensitizes T. b. brucei to human serum by modulating the essential cathepsin, CATL, a lysosomal cysteine peptidase. A second cathepsin, CATB, likely to be dispensable for growth in in vitro culture, has little or no impact on human-serum sensitivity. Our findings reveal major and novel determinants of human-serum sensitivity in T. b. brucei. They also shed light on the lysosomal protein-protein interactions that render T. b. brucei exquisitely sensitive to lytic factors in human serum, and indicate that CATL, an important potential drug target, has the capacity to resist these factors. PMID:24830321

Alsford, Sam; Currier, Rachel B.; Guerra-Assunção, José Afonso; Clark, Taane G.; Horn, David

2014-01-01

223

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

224

Serum 25-hydroxyvitamin D levels in thalassaemia.  

PubMed Central

Serum 25-hydroxyvitamin D levels were measured in 36 thalassaemic children and 27 controls aged 5-15 years. Blood specimens were collected from the beginning of April until the end of October 1976. We considered as the winter period the first 3 months and the summer period the last 4 months. We found that (a) thalassaemic children had lower levels of serum 25-hydroxyvitamin D than controls: (b) there was a seasonal variation of serum 25-hydroxyvitamin D in both groups; and (c) the thalassaemic children had malabsorption of vitamin D. We suggest that the bone lesions in thalassaemic children are related to vitamin D deficiency. PMID:646452

Tsitoura, S; Amarilio, N; Lapatsanis, P; Pantelakis, S; Doxiadis, S

1978-01-01

225

The cathodic behavior of titanium: Serum effect.  

PubMed

The cathodic behavior of titanium was investigated in inorganic buffer solutions and in fetal bovine serum through potential sweep techniques. Under cathodic polarization, the oxygen reduction and the hydrogen evolution reactions were observed. It was found that the activity of the electrode toward the electron transfer increased with decreasing the electrode surface charge. The polarization curves recorded in serum displayed the same features as those observed in inorganic buffered solutions. However, organic molecules were likely adsorbed onto the titanium surface and the adsorption reactions were potential dependant. Additionally, it was noticed that the buffer capacity of serum could be overwhelmed by the progressive interface alkalinization during cathodic polarization. Furthermore, serum affected the corrosion current of the implant materials and the effect was pH-dependent. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 544-552, 2011. PMID:22120993

Contu, Francesco

2012-02-01

226

Chemical engineer  

NSDL National Science Digital Library

What do chemical engineers actually do? This is the introductory page for a set of materials about chemical engineering as a career. Here the job of a chemical engineer is defined and described. Chemical engineers often work with industrial manufacturing processes that involve a mix of chemistry and engineering. In the rest of the resource, students can examine a specialized job title associated with chemical engineering: process engineer. Students can view a five-minute video clip of the process engineer as he works in a fertilizer plant making ammonia and urea. Students follow the engineer around the plant as he checks pressure in chemical lines. Students get a glimpse of the inside of a furnace during the chemical-making process. Copyright 2005 Eisenhower National Clearinghouse

Project, Iowa P.

2002-01-01

227

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

228

Serum heme-albumin: an allosteric protein.  

PubMed

Heme scavenging by plasma proteins, including serum albumin (SA), provides protection against free-heme oxidative damage, limits access by pathogens to the heme, and contributes to iron homeostasis by recycling the heme iron. In turn, serum heme-albumin (SA-heme) acquires heme-based ligand-binding and (pseudo-)enzymatic properties. Heme binding to SA and SA-heme reactivity are allosterically and competitively modulated by endogenous and exogenous third components, this being relevant in pharmacotherapy management. PMID:19946891

Ascenzi, Paolo; Fasano, Mauro

2009-12-01

229

Radioimmunoassay for serum 11-deoxy-17-ketosteroids  

Microsoft Academic Search

A simplified method for evaluating serum 11-deoxy-17-ketosteroids (11-; deoxy-17-KS) equivalent to dehydroepiandrosterone sulfate (DHEAS) has been ; developed without solvolysis and chromatography. Blood serum or plasma (5 mu l) ; was added to 1 ml of ethanol, mixed, and centrifuged, and 10 or 20 mu l of the ; supernatant was evaporated to dryness and incubated with anti-11-deoxy-17-KS ; antiserum

H. Sekihara; N. Ohsawa

1974-01-01

230

Studies on ceruloplasmin of bovine serum  

E-print Network

was based upon that of Holmberg and Laurel1 (2). Blood collected from cattle slaughtered at the Meats Laboratory of the A. and M. College of Texas was allowed to clot and the separated serum was centrifuged for clarification and removal of the red cells...STUDIES ON CERULOPLASMXN OF BOVINE SERUM A Dissertation By CHARTS WALTER DEVOS Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements for the degree of DOCTOR...

Deyoe, Charles Walter

2013-10-04

231

[Pu(IV) behavior in the serum].  

PubMed

This paper presents the results of studies of the hydrolysis and polymerization of Pu(IV) in blood serum. With nitrite Pu(IV) solutions incubated with blood serum 20-34% of the nuclide were precipitated as hydroxide and 11-36% converted into polymeric forms bound by high molecular weight proteins. For citrate solutions, these values were 3.8 and 3.0%, respectively. PMID:6505160

Surova, Z I

1984-01-01

232

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

233

Serum protein-binding characteristics of vancomycin.  

PubMed Central

A synthesis of studies of serum protein binding of vancomycin and its reported abnormal binding in serum with very high concentrations of immunoglobulin A (IgA) suggests that this antibiotic may be bound to more than one serum protein. Using an ultrafiltration method for separating free from bound drug and high-performance liquid chromatography to measure drug concentration, we studied the binding characteristics of vancomycin for alpha-1 acid glycoprotein, IgG, IgM, IgA, and albumin. The results showed that vancomycin does not bind to alpha-1 acid glycoprotein, IgG, or IgM. Major binding to albumin and IgA occurs, and total drug binding to serum proteins can be fully explained by binding to these two proteins. We calculated an N (number of binding sites per molecule) of 1.3 +/- 0.4 and a K (association constant) of 3.3 x 10(5) +/- 6.3 x 10(4) M-1 (NK = 4.3 x 10(5) M-1) for binding to IgA, whereas the corresponding NK value for albumin was only 527.5 M-1, indicating that vancomycin preferentially binds to IgA. Very high concentrations of IgA in serum (i.e., grams per deciliter), such as in patients with IgA myeloma, may result in the paradox of high (total) concentrations of vancomycin in serum that may be clinically ineffective. PMID:8517702

Sun, H; Maderazo, E G; Krusell, A R

1993-01-01

234

Serum trace metals changes during pentamethylmelamine treatment  

SciTech Connect

Pentamethylmelamine (PMM) is a water soluble analogue of an investigational anticancer drug hexamethylmelamine. This paper presents results on serum levels of three trace elements (copper, zinc, and magnesium) during PMM treatment. Seven New Zealand male albino rabbits weighing 2.7-4.5 kg, separately housed and kept on standard diet were administered PMM intravenously (i.v.) in daily doses of 50 mg/kg BW for 4 days. Blood samples were collected in metal free tubes as fasting state before and during the first, second and fourth days of PMM treatment. Serum Cu, Zn, and Mg were determined by atomic absorption spectrophotometric assays. Student paired T test was used for statistical analysis. Pretreatment serum Cu levels 55.4 +/- 4.1 ..mu..g% significantly (p = 0.05) increased to 66.9 +/- 5.6, 94.3 +/- 5.0 and 96.0 +/- 4.9 on the 1, 2, and 4th day of PMM treatment. The pretreatment serum Zn 193.3 19.6 ..mu..g% significantly (p = 0.05) decreased to 155.7 +/- 22.0, 148.6 +/- 23.8 and 152.9 +/- 16.9 ..mu..g% at the corresponding time intervals. The pretreatment serum Mg levels 1.9 +/- 0.07 Mg% did not significantly change. These results indicate that daily i.v. PMM administration causes significant changes in serum Cu and Zn levels with inversed relationship between both changes.

Slavik, M.; Melton, G.; Wood, A.; Slavik, J.

1986-03-01

235

A portal factor influences serum calcium homeostasis.  

PubMed Central

In order to evaluate the importance of a portal factor in serum calcium homeostasis, end-to-side portacaval shunts were performed in groups of adult, male Lewis rats either before or after parathyroidectomy. Subsequent changes in serum calcium values were followed. When parathyroidectomy was performed one day or 28 days after a portacaval shunt, hypocalcemic changes occurred soon after. However, in these shunted, parathyroidectomized animals which were maintained on a normal calcium diet the serum calcium concentrations soon began to rise and by three weeks after operationthe rats became normocalcemic. In animals which had a portacaval shunt performed three days after parathyroidectomy, the serum calcium levels again rose and became normal in approximately three weeks. In the shunted, parathyroidectomized animals, both the serum calcium and phosphorus concentrations remained normal as long as the rats were maintained ona normal calcium diet. When a low calcium diet was introduced, marked hypocalcemia occurred and serum parathyroid hormone values were barely detectable, both of which attest to the completeness of parathyroidectomy. These data support the hypothesis that following portacaval shunt, a calcium elevating factor, which is similar in action to parathyroid hormone but is not PTH itself, bypasses the liver and becomes effective in the systemic circulation. It acts to correct the hypocalcemia and hyperphosphatemia of parathyroidectomized rats. The possible role of various known gastrointestinal factors in this process is discussed. PMID:7425692

Lee, C H; Kaplan, E L; Sugimoto, J; Heath, H

1980-01-01

236

Neuroticism, depressive symptoms, and serum BDNF  

PubMed Central

Objective Animal models and clinical studies suggest that brain-derived neurotrophic factor (BDNF) is involved in the pathophysiology of depression. We test whether serum and plasma levels of BDNF are associated with trait Neuroticism and its facets, and with state measure of depressive symptoms. Method In a community-based cohort (N = 2099) we measured serum and plasma BDNF concentration, administered the Revised NEO Personality Inventory (NEO-PI-R) and the Center for Epidemiologic Studies Depression Scale (CES-D). Covariates included age, sex, cigarette smoking, obesity, and antidepressant use. Results Serum BDNF concentrations were inversely related to Neuroticism (r = ?0.074, P < 0.001), in particular the Depression facet (r = ?0.08, P < 0.001). Lower BDNF concentrations were also associated with severe depressive symptoms (CES-D ? 28; OR = 0.906; 95%CI = 0.851–0.965). The association of serum BDNF with Neuroticism was independent of depressive symptoms, indicating that serum BDNF might represent a biological correlate of Neuroticism and not just of transient depressive states. Plasma BDNF was not associated with measures of depression. Conclusions Our study suggests that lower serum BDNF is associated with both a dispositional vulnerability to depression and acute depressive states in the general population. PMID:21949427

Terracciano, Antonio; Lobina, Monia; Piras, Maria Grazia; Mulas, Antonella; Cannas, Alessandra; Meirelles, Osorio; Sutin, Angelina R.; Zonderman, Alan B; Uda, Manuela; Crisponi, Laura; Schlessinger, David

2011-01-01

237

Serum effects confound the neuroleptic radioreceptor assay  

SciTech Connect

The neuroleptic radioreceptor assay (NRRA) is used widely to monitor total neuroleptic-like activity (NLA) in patients taking one or more antipsychotic drugs. In studies with striata from rat or cow brain, it was found that sera from healthy, drug free volunteers, when used at 50 ..mu..L/1 mL assay volume, caused marked inhibition of binding. Although any sample of serum causes reproducible inhibition with a given preparation of bovine or rat striatal membranes, the effects of various serum samples may differ markedly when several striatal membrane preparations are compared. Moreover, samples taken from people at different times may also vary, although less than the interindividual differences. Despite this variance, the slopes of log-logit plots were equal to 1 either in the presence or absence of serum. Because of the differences in the interaction of individual sera with different membrane preparations, it is difficult to compensate accurately for this serum effect by simply including control serum in the standard curve. Thus, the use of the NRRA as a quantitative tool in the clinical pharmacology of neuroleptics may be limited by this non-specific effect of serum, and this finding may offer one explanation for some of the inconsistencies found in comparing the NRRA with direct analytical methods. 17 references, 2 figures, 2 tables.

Mailman, R.B.; DeHaven, D.L.; Halpern, E.A.; Lewis, M.H.

1984-03-12

238

Serum concentrations of haptoglobin and serum amyloid A in water buffaloes (Bubalus bubalis) with abomasal ulcer  

PubMed Central

To evaluate the serum concentrations of haptoglobin (Hp) and serum amyloid A (SAA) in water buffaloes with abomasal ulcers, the abomasums of 100 randomly selected water buffaloes were examined after slaughter. Type I abomasal ulcers were found in 56 out of 100 buffaloes. Serum concentrations of Hp and SAA were measured. There was no significant difference between affected and non-affected buffaloes in the serum concentrations of Hp and SAA. The serum concentrations of Hp and SAA had no significant correlation with age and the serum SAA revealed no significant correlation with the number of abomasal ulcers. A significant correlation was found between the serum Hp and the number of abomasal ulcers (r =0.29, p = 0.04). There was no significant difference in the serum concentrations of Hp and SAA between buffaloes with different ulcer locations in the abomasums. Although more work on a larger number of animals is required in this area, it seems that the measurement of the serum Hp can be used to predict the abundance of type I abomasal ulcers.

Tajik, Javad; Nazifi, Saeed; Heidari, Mahdi; Babazadeh, Marzieh

2012-01-01

239

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

240

Chemical modification of polymers and properties of functionalized polymers  

NASA Astrophysics Data System (ADS)

The work presented in this thesis is divided into four chapters. Chapter I describes the control of the crystallization behavior of syndiotactic polystyrene (sPS) by chemical modification of sPS using sulfonation. In Chapter II, preparation of wood-ceramic composites through sol-gel processes is described. Chapter III describes the end-functionalization of poly(ethylene oxide)s (PEOs), and the interfacial properties of the functionalized PEOs. Finally, the distribution of chain conformation of PEO in the liquid state is discussed in Chapter IV. Direct sulfonation of highly stereoregular syndiotactic polystyrene (sPS) has been accomplished in chloroform. The degree of sulfonation can be effectively controlled. The crystallization behavior of sulfonated sPS is considerably different than the unmodified polymer. The crystallinity and the crystallization kinetics of sPS decrease with increasing extent of modification. Wood-ceramic composites were prepared by introducing a ceramic component into pine, a softwood, through sol-gel processes. Several ceramic precursors, including SiClsb4, Si(OCHsb3)sb4, and CHsb3SiClsb3, were used. The ceramic content introduced into the wood structure can be controlled by varying the reaction time and the moisture content of wood. The modification of wood by CHsb3SiClsb3 in supercritical COsb2 penetrated the entire wood structure, generating a macroscopically uniform distribution of the ceramic component in wood. Samples with one or both ends of monodisperse PEO functionalized with perfluorodecanoyl groups (PEOspF or PEOspF2) were synthesized and blends of these end-capped PEOs with PEOs of the same molecular weight (Msbn˜2000 - ˜16000) were prepared as cast films. Due to the lower surface energy of the fluorocarbon end groups, the modified PEOs preferentially adsorb to the free polymer surface. The surface concentration of the perfluoroalkyl end groups was measured by XPS which indicates that perfluoroalkyl chain ends adsorb to the polymer surface in a reasonably close-packed fashion (at all molecular weights) and leave a zone depleted of fluorine immediately beneath the highly fluorinated surface region. There is only a slight effect of molecular weight on surface fluorine content indicating a "stretched brush" conformation for the higher molecular weight samples. The adsorption of these polymers at the air-water interface was studied as well. The packing density and the orientation angle of the fluorinated chain end segregated at the interface were assessed by external reflectance IR. Isotropic Raman spectra of PEO in aqueous solution and in the melt were simulated by superposing calculated spectra resulting from a series of normal coordinate calculations performed for an ensemble of conformers, and compared with the corresponding experimental results. The conformational distribution for poly(ethylene oxide) in the molten state favors the tgg' conformer, and the aqueous solution of poly(ethylene oxide) contains mostly tgt conformers. The results for PEO were supported by measurements and computations made using 1,2-dimethoxyethane as a model.

Su, Zhaohui

241

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

242

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, João; Tomaz, Isabel; Kiss, Tamás

2009-04-01

243

Serum alters the uptake and relative potencies of halogenated aromatic hydrocarbons in cell culture bioassays.  

PubMed

The effects of many chemicals on cellular processes are governed by their ability to enter the cell, which is in turn a function of the composition of the cell's external environment. To examine this relationship, the effect of serum in cell culture medium on the bioavailability of cytochrome P450 1A (CYP1A)-inducing compounds was determined in PLHC-1 (Poeciliopsis lucida hepatocellular carcinoma) cells. The presence of 10% calf serum in the medium increased the EC50 (effective concentration to achieve 50% maximal response) for induction of ethoxyresorufin O-deethylase (EROD) activity by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) 20-fold as compared to treatment in serum-free medium. Measurement of [3H]TCDD uptake and Ah receptor binding indicated that the apparent difference in potencies was a result of decreased bioavailability in the presence of serum, effectively reducing the concentration of TCDD within the cells. Induction of EROD and CYP1A protein in response to treatment with each of three coplanar polychlorinated biphenyls (PCB congeners 77, 126, and 169) was similarly affected by serum, although the magnitude varied among inducers and assays. Relative potencies (calculated as EC50TCDD / EC50PCB) for EROD induction by the three PCBs were significantly higher in the absence of serum. However, serum showed no significant effect on the relative potencies for CYP1A protein induction. These results demonstrate that measured inducing potencies, and relative potencies for EROD induction, by halogenated aromatic hydrocarbons are strongly dependent on the composition of culture medium, which can lead to artificial differences in comparisons among cell types. PMID:10696780

Hestermann, E V; Stegeman, J J; Hahn, M E

2000-02-01

244

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

245

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

246

Null Results in Brief Associations of Serum Carotenoid Levels with Serum  

E-print Network

-I and Insulin-like Growth Factor Binding Protein-3 Levels in Black Men and White Men Young L. Kim,1 David R it seems to be the most effective quencher of singlet oxygen and free radicals (2). In addi- tion of serum carotenoid concentrations with serum IGF-I and IGFBP-3 concen- trations in Black men and White men

Kim, Young L.

247

Concentrations of Environmental Phenols and Parabens in Milk, Urine and Serum of Lactating North Carolina Women.  

PubMed

Phenols and parabens show some evidence for endocrine disruption in laboratory animals. The goal of the Methods Advancement for Milk Analysis (MAMA) Study was to develop or adapt methods to measure parabens (methyl, ethyl, butyl, propyl) and phenols (bisphenol A (BPA), 2,4- and 2,5-dichlorophenol, benzophenone-3, triclosan) in urine, milk and serum twice during lactation, to compare concentrations across matrices and with endogenous biomarkers among 34 North Carolina women. These non-persistent chemicals were detected in most urine samples (53-100%) and less frequently in milk or serum; concentrations differed by matrix. Although urinary parabens, triclosan and dichlorophenols concentrations correlated significantly at two time points, those of BPA and benzophenone-3 did not, suggesting considerable variability in those exposures. These pilot data suggest that nursing mothers are exposed to phenols and parabens; urine is the best measurement matrix; and correlations between chemical and endogenous immune-related biomarkers merit further investigation. PMID:25463527

Hines, Erin P; Mendola, Pauline; vonEhrenstein, Ondine S; Ye, Xiaoyun; Calafat, Antonia M; Fenton, Suzanne E

2014-11-22

248

Methsuximide reduces valproic acid serum levels.  

PubMed

The authors investigated whether methsuximide affects serum levels of valproic acid. Pre-morning-dose serum valproic acid levels were measured in 17 patients (12 male, 5 female; age range, 8-19; mean, 14.5 years) who either started or stopped taking methsuximide but whose dose of valproate and other medication remained unchanged. Four of these patients both started and stopped taking methsuximide. For the whole group the mean valproic acid level (+/- standard error) while not taking methsuximide was 81.9 +/- 5.3 mg/L and while taking methsuximide was 55.7 +/- 4.3 mg/L. The difference between the means was highly significant (paired t test, p < 0.001). The mean valproic acid serum level before taking methsuximide was 85.4 +/- 4.5 mg/L (14 patients), which decreased to 58.2 +/- 4.8 mg/L while taking methsuximide (difference highly significant, p < 0.001). In the eight patients who stopped taking methsuximide the mean serum level increased from 49.8 +/- 7.5 mg/L to 71.7 +/- 8.5 mg/L (difference significant p = 0.025). Because methsuximide reduces valproic acid serum levels, it may be necessary to increase the valproate dose when methsuximide is added or reduce the valproate dose when methsuximide therapy stops, to avoid loss of seizure control or valproate toxicity respectively. PMID:11802106

Besag, F M; Berry, D J; Vasey, M

2001-12-01

249

Radioimmunoassy for phencyclidine (PCP) in serum. [Dogs  

SciTech Connect

This accurate, sensitive radioimmunoassay for determining phencyclidine concentrations in serum specimens involves the use of anti-phencyclidine sera, 0.1 mL of serum specimen, an iodinated tracer, and a solid-phase separation. Phencyclidine metabolities do not show significant cross reactivity, but several phencyclidine analogs do cross react. Within-run coefficients of variation for human and dog serum ranged from 2.5 to 13% for concentrations from 2.0 to 500 ..mu..g/L. Day-to-day coefficients of variation for human and dog serum ranged from 4.3 to 16.7% for concentrations ranging from 2.0 to 09.0 ..mu..g/L. The sensitivity of the radioimmunoassay is <0.5 ..mu..g/L. Thirty serum specimens from two dogs given 1 mg of phencyclidine per kilogram body weight were analyzed by radioimmunoassay and a gas-chromatographic method. Nonparametris statistical comparison and linear regression showed that results from the two procedures correlate well (r/sup 2/ = 0.952). Concentration-time data from the two dogs are presented to illustrate the utility of the radioimmunoassay for examining phencyclidine disposition.

Owens, S.M.; Woodworth, J.; Mayersohn, M.

1982-07-01

250

CHEMICAL ENGINEERING AND MANUFACTURING CHEMICAL ENGINEERING  

E-print Network

CHEMICAL ENGINEERING AND MANUFACTURING CHEMICAL ENGINEERING Objective Chemical Engineers of chemicals. This lesson introduces students to one component of chemical engineering: food processing, and a chemical engineer 2. How chemical engineers are involved in food production 3. That chemical engineers need

Provancher, William

251

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)

252

Chemical sensors  

DOEpatents

Sensors responsive to small changes in the concentration of chemical species are disclosed, comprising (a) a mechanochemically responsive polymeric film capable of expansion or contraction in response to a change in its chemical environment, operatively coupled to (b) a transducer capable of directly converting said expansion or contraction to a measurable electrical response.

Lowell, Jr., James R. (Bend, OR); Edlund, David J. (Bend, OR); Friesen, Dwayne T. (Bend, OR); Rayfield, George W. (Bend, OR)

1991-01-01

253

Chemical sensors  

DOEpatents

Sensors responsive to small changes in the concentration of chemical species are disclosed. The sensors comprise a mechanochemically responsive polymeric film capable of expansion or contraction in response to a change in its chemical environment. They are operatively coupled to a transducer capable of directly converting the expansion or contraction to a measurable electrical response. 9 figures.

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

1991-07-02

254

Chemical geodynamics  

Microsoft Academic Search

Consideration is given to the following three principal boundary conditions relating to the nature and development of chemical structure in the earth's mantle: (1) inferred scale lengths for mantle chemical heterogeneities, (2) interrelationships of the various isotopic tracers, and (3) the bulk composition of the earth. These boundary conditions are integrated with geophysical constraints in order to evaluate models for

A. Zindler; S. R. Hart

1986-01-01

255

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

256

Chemical preconcentrator  

DOEpatents

A chemical preconcentrator is disclosed with applications to chemical sensing and analysis. The preconcentrator can be formed by depositing a resistive heating element (e.g. platinum) over a membrane (e.g. silicon nitride) suspended above a substrate. A coating of a sorptive material (e.g. a microporous hydrophobic sol-gel coating or a polymer coating) is formed on the suspended membrane proximate to the heating element to selective sorb one or more chemical species of interest over a time period, thereby concentrating the chemical species in the sorptive material. Upon heating the sorptive material with the resistive heating element, the sorbed chemical species are released for detection and analysis in a relatively high concentration and over a relatively short time period. The sorptive material can be made to selectively sorb particular chemical species of interest while not substantially sorbing other chemical species not of interest. The present invention has applications for use in forming high-sensitivity, rapid-response miniaturized chemical analysis systems (e.g. a "chem lab on a chip").

Manginell, Ronald P. (Albuquerque, NM); Frye-Mason, Gregory C. (Cedar Crest, NM)

2001-01-01

257

The effects of perfluorinated chemicals on adipocyte differentiation in vitro.  

PubMed

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 that are detected worldwide in human serum and animal tissues. This study was designed to evaluate the potential for PFAAs to affect adipocyte differentiation and lipid accumulation using mouse 3T3-L1 cells. Cells were treated with perfluorooctanoic acid (PFOA) (5-100?µM), perfluorononanoic acid (PFNA) (5-100?µM), perfluorooctane sulfonate (PFOS) (50-300?µM), perfluorohexane sulfonate (PFHxS) (40-250?µM), the peroxisome proliferator activated receptor (PPAR) PPAR? agonist Wyeth-14,643 (WY-14,643), and the PPAR? agonist rosiglitazone. The PPAR? agonist was included as a positive control as this pathway is critical to adipocyte differentiation. The PPAR? agonist was included as the PFAA compounds are known activators of this pathway. Cells were assessed morphometrically and biochemically for number, size, and lipid content. RNA was extracted for qPCR analysis of 13 genes selected for their importance in adipocyte differentiation and lipid metabolism. There was a significant concentration-related increase in cell number and decreased cell size after exposure to PFOA, PFHxS, PFOS, and PFNA. All four PFAA treatments produced a concentration-related decrease in the calculated average area occupied by lipid per cell. However, total triglyceride levels per well increased with a concentration-related trend for all compounds, likely due to the increased cell number. Expression of mRNA for the selected genes was affected by all exposures and the specific impacts depended on the particular compound and concentration. Acox1 and Gapdh were upregulated by all six compounds. The strongest overall effect was a nearly 10-fold induction of Scd1 by PFHxS. The sulfonated PFAAs produced numerous, strong changes in gene expression similar to the effects after treatment with the PPAR? agonist rosiglitazone. By comparison, the effects on gene expression were muted for the carboxylated PFAAs and for the PPAR? agonist WY-14,643. In summary, all perfluorinated compounds increased cell number, decreased cell size, increased total triglyceride, and altered expression of genes associated with adipocyte differentiation and lipid metabolism. PMID:25448844

Watkins, Andrew M; Wood, Carmen R; Lin, Mimi T; Abbott, Barbara D

2015-01-15

258

Concentrations of organochlorine pesticides and polychlorinated biphenyls in human serum and adipose tissue from Bolivia  

Microsoft Academic Search

Organochlorine pesticides and polychlorinated biphenyls (PCBs) are synthetic chemicals that are highly resistant to biodegradation and have proven adverse health effects. The objectives of this study were to determine concentrations of three selected organochlorine pesticides (p,p?-DDT, p,p?-DDE, HCB) and three specific PCB congeners (PCB 138, 153, 180) in adipose tissue and serum samples from an urban adult population (n=112) in

J. P. Arrebola; M. Cuellar; E. Claure; M. Quevedo; S. R. Antelo; E. Mutch; E. Ramirez; M. F. Fernandez; N. Olea; L. A. Mercado

259

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...

260

Serum Sodium Levels in Sigmoid Volvulus  

PubMed Central

Objective Sigmoid volvulus (SV) is an uncommon type of large bowel obstruction. This study sought to determine serum sodium concentrations in patients with SV. Materials and Methods The records of 89 patients with SV and 40 patients with obstructive rectosigmoid cancer (ORC) were reviewed retrospectively Results The mean serum sodium concentrations in patients with SV and in those with ORC were 138.4±4.5 mEq/L and 137.7±3.2 mEq/L, respectively (t:0.7, P>0.05). The numbers of hyponatremic and hypernatremic patients were 13 vs. 4 and 1 vs. 0, respectively, in the SV and ORC groups (x2:0.5, P>0.05). Conclusion No cause-effect relationship was determined between serum sodium concentrations and SV.

Atamanalp, S. Selcuk; Keles, M. Sait; Ozturk, Gurkan; Ozogul, Bunyami; K?saoglu, Abdullah; Akbas, Ahmet

2009-01-01

261

Serum enzyme monitoring in sports medicine.  

PubMed

Total creatin kinase (CK) and lactate dehydrogenase (LDH) serum levels depend on age, gender, race, muscle mass, physical activity, and climatic conditions. High CK serum levels in athletes following rest and without any further predisposing factors should prompt a full diagnostic workup, with special regards to signs of muscle weakness or other signs not always evident. In subjects who have silent myopathy, repeated intense prolonged exercise may produce negative effects, because given the continuous loss of muscle proteins, it does not induce the physiological muscle adaptations to physical training. Serum total LDH and specific isozyme activities change with the training status of the athlete. Variation in LDH isozymes profile might have a role in studying muscle response to training. PMID:18206566

Brancaccio, Paola; Maffulli, Nicola; Buonauro, Rosa; Limongelli, Francesco Mario

2008-01-01

262

Two new oral chemical biomarkers for coyotes.  

PubMed

Pentachlorobenzene (PeCB) and 1,2,3,4-tetrachlorobenzene (TeCB) were evaluated as oral chemical biomarkers when administered to coyotes (Canis latrans) during the period of 31 January to 10 August 1994. Three coyotes each received 100 mg of PeCB and three received 100 mg of TeCB, each in a mineral oil formulation. Three additional coyotes received only the mineral oil carrier. Muscle and adipose tissues, blood serum, and fecal samples were evaluated by capillary gas chromatography with electron capture detection for 120 days following administration. Residues of PeCB were detected in serum, feces, and adipose and muscle tissues for 120 days post-treatment; TeCB residues were detected in feces and serum at 1 and 8 days post-treatment and in adipose tissue at 30 days post-treatment. Residues of TeCB were not detected in muscle tissue at any point in the study. PMID:8827677

Kimball, B A; Windberg, L A; Furcolow, C A; Roetto, M; Johnston, J J

1996-07-01

263

Serum magnesium in hospital admitted diabetic patients.  

PubMed

Magnesium depletion has a negative impact on glucose homeostasis and insulin sensitivity in diabetic patients. Low plasma magnesium concentration is a highly specific indicator of poor magnesium status. This case control study was conducted in Mymensingh Medical College Hospital, Bangladesh, from May 2011 to April 2012. This study was done to assess the serum magnesium level in diabetic and non-diabetic patients and to find out the association between serum magnesium, blood glucose and duration of diabetes mellitus. Serum magnesium concentrations were determined in 50 diabetics and 50 age and sex matched non-diabetic patients or attendants for controls. Among the case and control group 32 were male and 18 were female. Mean age of control group was 54.42±2.33 and study group was 55.78±2.43 years. Duration of diabetes of case group in which 50% of patients have diabetes for up to 4 years, 18% of patients have diabetes for 5-9 years, 5% of patients have for 10-14 years and 2% of patients have diabetes for 15 years and above. Serum magnesium concentrations below the normal reference range for study group was 44% and control group was 6%. The mean serum magnesium level of study group was 0.70±0.01mmol/L and that of control group was 0.83±0.02mmol/L. So, the difference in serum magnesium level between two groups were statistically highly significant (p = 0.001). Correlation between FBS and SML of study group, which is negative (r = - 0.182). There is opposite relation among the characteristics as r is negative. And also correlation between 2HAFB and SML of study group, which is negative (r = - 0.06). There is opposite relation among the characteristics as r is negative. PMID:24584369

Azad, K M; Sutradhar, S R; Khan, N A; Haque, M F; Sumon, S M; Barman, T K; Islam, M Z; Haque, M R; Pandit, H; Ahmed, S

2014-01-01

264

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

265

Association Between Serum Levels of Carotenoids and Serum Asymmetric Dimethylarginine Levels in Japanese Subjects  

PubMed Central

Background Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelium nitric oxide synthase (NOS). ADMA binds to a substrate-binding site of NOS and then inhibits nitric oxide production from vascular endothelial cells. Elevated ADMA levels are a risk factor for cardiovascular disease. Recently, it was reported that plasma ADMA levels were negatively correlated with vegetable and fruit consumption. The purpose of this study was to examine the association between serum levels of carotenoids and serum ADMA levels in Japanese subjects. Methods We conducted a cross-sectional study of 470 subjects (203 men and 267 women) who attended a health examination in August 2011. Serum levels of several carotenoids were separately measured by high-performance liquid chromatography. Serum ADMA levels were determined by using an enzyme-linked immunosorbent assay kit. Results In women, the multivariate-adjusted odds ratios (ORs) of elevated serum ADMA levels were significantly decreased in the highest tertile for ?-cryptoxanthin (OR 0.47, 95% CI 0.23–0.95), ?-carotene (OR 0.39, 95% CI 0.18–0.79), and ?-carotene (OR 0.36, 95% CI 0.17–0.73) compared to the lowest tertile. In men, significantly decreased ORs were observed in the highest tertiles of serum zeaxanthin/lutein (OR 0.23, 95% CI 0.06–0.69) and ?-carotene (OR 0.26, 95% CI 0.07–0.82), and in the middle and the highest tertiles of serum ?-carotene (OR 0.27, 95% CI 0.09–0.74 and OR 0.20, 95% CI 0.03–0.88, respectively) when the tertile cutoff points of women were extrapolated to men. Conclusions Higher serum levels of carotenoids, such as ?-carotene and ?-carotene, may help to prevent elevated serum ADMA levels in Japanese subjects. PMID:24727752

Watarai, Rika; Suzuki, Koji; Ichino, Naohiro; Osakabe, Keisuke; Sugimoto, Keiko; Yamada, Hiroya; Hamajima, Takeshi; Hamajima, Nobuyuki; Inoue, Takashi

2014-01-01

266

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

267

Chemical lasers  

NASA Astrophysics Data System (ADS)

Fundamental properties of chemical lasers are presented and principal systems described in the nonclassified literature are reviewed. The fundamentals of the production of inversion in molecular gases by chemical processes are discussed. Iodine, HF, and DF lasers are described. The chemical reaction in the pulsed chemical HF and DF lasers is introduced by a transverse electrical discharge. In spite of the high dissociation energy and the electronegative properties which are unfavorable for a stable discharge regime, SF6 is used as fluorine source for safety reasons. The pulse energies reach 26 J in agreement with estimated values. The advantage of the present system is that is can also operate as CO2 laser in the TEA mode. The radiation of DF lasers is particularly interesting for military near-Earth applications because of its good transmission properties in the atmosphere.

Hugenschmidt, M.; Wey, J.

1985-05-01

268

Chemical Peeling  

MedlinePLUS

... the skin heals can cause unwanted side effects ranging from infection to scarring. If you have any ... Tanzi EL and Alster TS. “Skin Resurfacing: Ablative Lasers, Chemical Peels, and Dermabrasion.” In: Wolff K, Goldsmith ...

269

Chemical Emergency  

MedlinePLUS

... can be recycled, which is better for our environment. If you have questions about how to dispose of a chemical, call the facility or the environmental or recycling agency to learn the proper method of disposal. ...

270

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

271

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

272

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.

Lowell, Jr., James R. (Bend, OR); Edlund, David J. (Bend, OR); Friesen, Dwayne T. (Bend, OR); Rayfield, George W. (Eugene, OR)

1992-01-01

273

Serum calcitonin negative Medullary thyroid carcinoma  

Microsoft Academic Search

BACKGROUND: Medullary thyroid carcinomas (MTC) constitute about 5 to 7 % of thyroid neoplasms. They originate from parafollicular C cells which produce Calcitonin, a hormone which has an impact on calcium metabolism and represents the biochemical activity of MTC. In rare cases pre-operative serum calcitonin can be negative. CASE PRESENTATION: We report on a 73-year-old female patient with a rare

Michael Sand; Marcos Gelos; Daniel Sand; Falk G Bechara; Gerd Bonhag; Ellen Welsing; Benno Mann

2006-01-01

274

ORIGINAL ARTICLE Serum apolipoprotein B predicts dyslipidemia,  

E-print Network

levels in predicting metabolic syndrome (MS), hypertension, atherogenic dyslipidemia and type II diabetes with metabolic syndrome (MS). Apo B(100) levels in 298 persons with diabetes demonstrated an association with MSORIGINAL ARTICLE Serum apolipoprotein B predicts dyslipidemia, metabolic syndrome and, in women

Cai, Long

275

Menaquinones content of human serum and feces  

Technology Transfer Automated Retrieval System (TEKTRAN)

Bacterially-synthesized menaquinones (MKn) may contribute to vitamin K (VK) nutriture. There are limited data on interindividual variability in endogenous MK synthesis and its relation to circulating forms of VK. Serum and fecal VK concentrations were assessed in 13 healthy adults (45-65 yr) consumi...

276

Two-Dimensional Electrophoresis of Serum Proteins  

Microsoft Academic Search

A METHOD of zone electrophoresis in starch gels has recently been described by one of us1. The high degree of resolution obtained with this method when applied to serum appears to be due to the use of a supporting medium the pore size of which approaches the molecular dimensions of some of the proteins involved, so that resolution by molecular

O. Smithies; M. D. POULIK

1956-01-01

277

Serum Prolactin Levels in Psoriasis Vulgaris  

PubMed Central

Background. Psoriasis is a chronic inflammatory skin disease affecting approximately 1–3% of Caucasians. Prolactin has proliferative effects on human keratinocytes, a dominant feature of psoriasis, and it is thought that this hormone may play a role in the pathogenesis of the disease. This study was conducted to confirm or refute these findings in order to better understand the disease pathogenesis. Methods. The subjects were 90 individuals aged between 15 and 47 years. They were divided into three groups of 30 individuals each: psoriatic patients, atopic dermatitis patients, and control group. A questionnaire was filled regarding their demographic and medical history. All of the study subjects underwent venous blood sampling (5?mL), and serum TSH and prolactin levels were checked. Subjects with abnormal TSH were omitted. Results. None of the patients in the study had raised prolactin, and there was no significant difference in the serum prolactin level between patients with psoriasis and atopic dermatitis and the control group. There was no relationship between the severity of psoriasis and serum levels of prolactin. Conclusion. Prolactin does not seem to play a role in the pathogenesis of psoriasis as its serum levels are comparable with atopic dermatitis patients and that of the normal population. PMID:24707406

Handjani, Farhad; Saki, Nasrin; Ahrari, Iman; Ebrahimi, Mehdi; Khorrami, Mohammad Mehdi; Nematollahi, Parastoo

2014-01-01

278

Serum Potassium Levels in Sigmoid Volvulus  

PubMed Central

Objective: This study aimed to determine the serum potassium concentrations in patients with sigmoid volvulus (SV), which is a rare large bowel obstruction. Materials and Methods: The records of 86 patients with SV were reviewed retrospectively, while the records of 41 patients diagnosed with obstructive rectosigmoid cancer (ORC) were considered as the control group and as such, served as a source for comparison. Results: The analysis revealed a mean serum potassium concentration of 3.9 ± 0.6 mEq/L for the patients with SV, while the mean potassium concentration was 3.9 ± 0.5 mEq/L for the patients diagnosed with ORC (t:0.1, P>0.05). The number of hypokalemic and hyperkalemic patients identified in this study sample were 11 versus 5 patients and 1 versus 0 patients, respectively for the SV and ORC groups (x2 = 0.1 and 0.5, respectively with a P>0.05). Conclusions: No cause-and-effect relationship was observed between the serum potassium concentrations and SV. The serum potassium concentration is not pathognomonic for SV.

Atamanalp, S. Selcuk; Keles, M. Sait; Aydinli, Bulent

2009-01-01

279

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

280

9 CFR 147.2 - The rapid serum test. 2  

Code of Federal Regulations, 2010 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...

2010-01-01

281

Increased Serum Alkaline Phosphatase and Serum Phosphate as Predictors of Mortality after Stroke  

PubMed Central

Context: Serum Alkaline phosphatase (ALP) & phosphate are considered to be indicators of vascular calcification. Link between bone metabolism, vascular calcification, cardiovascular events have been well studied in chronic kidney disease and ischemic heart disease. Aims: To determine that increased serum phosphate and alkaline phosphatase are predictors of mortality rates and recurrent vascular events in stroke. Materials and Methods: Sixty patients admitted with acute stroke (ischemic & haemorrhagic) were included in the study. Their baseline clinical characteristics and biochemical parameters including serum ALP and phosphate were noted. All patients were followed up for a period of one year. The all- cause mortality, the mortality due to cardiovascular events and recurrent vascular events without death were noted during the follow up. Statistical analyses were done to look for any correlation between mortality and baseline levels of serum ALP and phosphate. Results: Of the 60 patients, 8 (13.3%) patients were lost for follow up. Fourteen (26.9%) patients died; of which 12 deaths were due to vascular causes and 2 deaths were due to non vascular causes. Increasing levels of serum ALP and phosphate correlated with all cause mortality and recurrent vascular events without death Conclusion: Serum ALP and phosphate prove to be cost effective prognostic indicator of mortality and recurrent vascular events in stroke. This finding has to be confirmed with studies including larger population. Further research on ALP inhibitors, Vitamin D analogues and phosphate binders to improve mortality in stroke population can be encouraged. PMID:25300293

S, Pratibha; JB, Agadi

2014-01-01

282

Sex-Associated Differences in Serum Proteins of Mice  

Microsoft Academic Search

Agar electrophoresis of serum from mice of C57BL\\/10-H-2d, B10.Sn, A.SW, A.CA, R III, and P1 inbred strains shows that the females have a lower concentration of alpha -1 serum globulin than the males and, in some strains, the females also have a lower concentration of alpha -2 and beta -serum globulin. Females of the A.SW strain have a higher serum

E. Espinosa; E. Canelo; M. Bravo; O. Gonzalez

1964-01-01

283

Clustering of serum calcium and magnesium concentrations in siblings.  

PubMed

Concentrations of both serum calcium, adjusted for albumin, and serum magnesium of siblings from 23 families were found to cluster around different concentrations within the normal reference interval. Variation between families accounted for 37% of the total variation in calcium and 28% of that in magnesium. A disturbance of serum calcium or magnesium homeostasis in an individual resulting in an altered serum concentration that remains within the reference interval might be recognized by examining values in siblings. PMID:3943197

Payne, R B; Jones, D P; Walker, A P; Evans, R T

1986-02-01

284

Comparison of fortified calf serum, serum substitutes and fetal calf serum with or without extenders for propagation of cell cultures for virus plaque assays.  

PubMed

Two studies comparing sewage-isolated and laboratory stock viruses were conducted to determine if alternative forms of serum or serum extenders could be used in place of fetal bovine serum without a significant loss of viral titer. In the first study, BGM cells were grown in standard MEM-L15 medium which was supplemented with Nuserum, Sigma serum replacement (CPSR-1), HyClone defined iron supplemented calf bovine serum, fetal bovine serum (FBS) or FBS supplemented with either SerXtend or Mito serum extenders. Comparison of virus titers showed that CPSR-1 gave the best overall results and was comparable to FBS. Of the serum extenders, only SerXtend improved virus recovery from sewage samples. In the second study, all sera were tested with and without SerXtend. In these experiments, SerXtend enhanced virus sensitivity of the BGM cell line grown in the HyClone serum but reduced the sensitivity of those cultured in Sigma serum. In both series, the growth of BGM cells was monitored for 12 weeks and all test products were shown to support long-term cell growth. PMID:2324238

Dahling, D R; Wright, B A

1990-03-01

285

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

286

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

287

[A comparative study of serum H-antibodies in typhoid patients and bacteria carriers].  

PubMed

A study was made of the dynamics of serum H-antibodies in typhoid patients depending on the period of the disease and the severity of its course; the blood sera of chronic carriers were examined as well. H-antibodies were determined in the indirect hemagglutination test with the use of erythrocyte H-dignoasticum. Antibodies of different physico-chemical nature (of IgG and IgM classes) were obtained by fractionation in columns with DEAE-cellulose. Results of the investigations showed that the titres of sum total serum H-antibodies failed to depend on the severity of the course of the disease. The maximum value of the mean geometrical titre of H-antibodies in the blood serum was determined on the 3rd-4th week from the onset of the disease. In chronic carriers the sum total H-antibody titres were greater than in typhoid patients. The serum H-antibody titres increased on account of IgG-globulins both in the typhoid patients and in carriers. PMID:941608

Sukhoroslova, L I; Rukhadze, E Z; Kapuka, L P; Trushina, V V

1976-05-01

288

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

289

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

290

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

291

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...

292

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

293

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

294

Serum Galactosyl Transferase Levels in Patients with Advanced Cancer  

Microsoft Academic Search

Serum galactosyl transferase was significantly higher in patients with various types of cancer than in age-matched controls. The highest serum enzyme levels were observed in the breast and respiratory cancer, followed by ovarian and gastrointestinal tumours; whereas the enzyme activity in prostatic cancer patients was not significantly higher than in the control subjects. In the cancer patients the serum levels

Ifor D. Capel; Helen M. Dorrell; Donald C. Williams; Iain W. F. Hanham; Harry N. Levitt

1982-01-01

295

Usefulness of Adult Bovine Serum for Helicobacter pylori Culture Media?  

PubMed Central

Fetal bovine serum (FBS) and adult bovine serum (BS) exhibited bactericidal activity against Helicobacter pylori at various levels, which were higher in BS than in FBS. The bactericidal activity was inactivated by heat treatment at 56°C for 30 min. Our results demonstrated that heat-treated BS is a useful serum source of H. pylori culture medium. PMID:16957036

Shibayama, Keigo; Nagasawa, Mitsuaki; Ando, Takafumi; Minami, Masaaki; Wachino, Jun-ichi; Suzuki, Satowa; Arakawa, Yoshichika

2006-01-01

296

Quantifying Serum Antiplague Antibody with a Fiber-Optic Biosensor  

Microsoft Academic Search

The fiber-optic biosensor, originally developed to detect hazardous biological agents such as protein toxins or bacterial cells, has been utilized to quantify the concentration of serum antiplague antibodies. This biosensor has been used to detect and quantify the plague fraction 1 antigen in serum, plasma, and whole-blood samples, but its ability to quantify serum antibodies has not been demonstrated. By

GEORGE P. ANDERSON; KEELEY D. KING; LYNN K. CAO; MEAGAN JACOBY; FRANCES S. LIGLER; JOHN EZZELL; Fort Detrick

1998-01-01

297

Mannose-Binding Lectin Serum Levels in Aphthous Ulcers  

Microsoft Academic Search

Objective: Mannose-binding lectin (MBL) is a C-type serum lectin that plays a key role in the innate immune response. Changes in MBL serum levels are related with recurrent infections. Before the development of a specific antibody response, MBL is already present in serum, and has a broad spectrum of binding to bacterial and infectious agents. The aim of the present

Özgün ÖZÇAKA; Nurgün BIÇAKÇI; Timur KÖSE; Ege Üniversitesi

298

Characterization of alkaline phosphatase in canine serum.  

PubMed

On the basis of carbohydrate structure, normal dog serum contains three basic types of serum alkaline phosphatase (SAP) corresponding to (1) highly branched complex (non-concanavalin A-binding), (2) complex, or (3) high-mannose (both concanavalin A-binding) oligosaccharide structures. Subsequent binding experiments with monoclonal antibody to intestinal alkaline phosphatase (AP) and bromotetramisole inhibition studies clearly indicated the presence of intestinal-like SAP. Concanavalin A (Con-A) binding characteristics suggested the presence of a bone-like SAP. Con-A-binding and isoelectric focusing results revealed the presence of two (type Ib and IIb) major SAP isoenzymes thought to be of hepatic origin. SAP isoenzymes appear to be modified when compared to tissue AP, particularly in regard to molecular size and, in some cases, carbohydrate structure. PMID:3582317

Amacher, D E; Smith, D J; Martz, L K; Hoffmann, W E

1987-01-01

299

Purification of NAD(+) glycohydrolase from human serum.  

PubMed

In the present study, NAD(+) glycohydrolase was purified from serum samples collected from healthy individuals using ammonium sulfate fractionation, Affi-Gel blue (Cibacron Blue F3GA) affinity chromatography, Sephadex G-100 column chromatography and isoelectric focusing. The final step was followed by a second Sephadex G-100 column chromatography assay in order to remove the ampholytes from the isoelectric focusing step. In terms of enhancement of specific activity, the NAD(+) glycohydrolase protein was purified ?480-fold, with a yield of 1% compared with the initial serum fraction. The purified fraction appeared to be homogeneous, with a molecular weight of 39 kDa, as revealed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, and also corresponded to the soluble (monomeric) form of surface antigen CD38. PMID:23946809

Co?kun, Ozlem; Nurten, Rüstem

2013-07-01

300

Purification of NAD+ glycohydrolase from human serum  

PubMed Central

In the present study, NAD+ glycohydrolase was purified from serum samples collected from healthy individuals using ammonium sulfate fractionation, Affi-Gel blue (Cibacron Blue F3GA) affinity chromatography, Sephadex G-100 column chromatography and isoelectric focusing. The final step was followed by a second Sephadex G-100 column chromatography assay in order to remove the ampholytes from the isoelectric focusing step. In terms of enhancement of specific activity, the NAD+ glycohydrolase protein was purified ?480-fold, with a yield of 1% compared with the initial serum fraction. The purified fraction appeared to be homogeneous, with a molecular weight of 39 kDa, as revealed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, and also corresponded to the soluble (monomeric) form of surface antigen CD38. PMID:23946809

CO?KUN, ÖZLEM; NURTEN, RÜSTEM

2013-01-01

301

Interaction of wogonin with bovine serum albumin  

Microsoft Academic Search

The binding of wogonin with bovine serum albumin (BSA) was investigated at different temperatures by fluorescence, circular dichroism (CD) and Fourier transform infrared spectroscopy (FT-IR) at pH7.40. The association constants K were determined by Stern–Volmer equation based on the quenching of the fluorescence of BSA in the presence of wogonin, which were in agreement with the constants calculated by Scatchard

Jianniao Tian; Jiaqin Liu; Zhide Hu; Xingguo Chen

2005-01-01

302

Serum cholesterol concentrations among Navajo Indians.  

PubMed Central

Navajo Indians have been reported by earlier investigators to have low concentrations of serum lipids and a low prevalence of hyperlipidemia, as well as low rates of ischemic heart disease. However, no data on serum lipid concentrations among Navajos have been reported for more than two decades. The authors conducted a study to determine the distribution of concentrations of serum total cholesterol (TC), high density lipoprotein cholesterol, low density lipoprotein cholesterol, and triglyceride among persons 25-74 years old living in a representative community on the Navajo Indian reservation. Data are reported for 255 subjects, 105 men and 150 women, ages 25-74 years. The authors compared these data to those for the general population as determined by the second National Health and Nutrition Examination Survey (NHANES II). TC concentrations among Navajo men were similar to those from NHANES II. TC concentrations among younger Navajo women were similar to those for women younger than 55 years from NHANES II, but were significantly lower among older Navajo women. While 27.6 percent of men ages 25-74 years studied in NHANES II had TC concentrations greater than 240 milligrams per deciliter, 33.8 percent of Navajo men had similarly elevated TC. However, the prevalence of serum TC concentrations greater than 240 milligrams per deciliter among Navajo women (17.5 percent) was about half that among women studied in NHANES II (32.9 percent). A similar pattern was found for low density lipoprotein cholesterol.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1738814

Sugarman, J R; Gilbert, T J; Percy, C A; Peter, D G

1992-01-01

303

Prediction of Creatinine Clearance from Serum Creatinine  

Microsoft Academic Search

A formula has been developed to predict creatinine clearance (Ccr) from serum creatinine (Scr) in adult males: Ccr = (140 – age) (wt kg)\\/72 × Scr(mg\\/100ml) (15% less in females). Derivation included the relationship found between age and 24-hour creatinine excretion\\/kg in 249 patients aged 18–92. Values for Ccr were predicted by this formula and four other methods and the

Donald W. Cockcroft; Henry Gault

1976-01-01

304

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.

305

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

306

Chemical Evolution  

E-print Network

In this series of lectures we first describe the basic ingredients of galactic chemical evolution and discuss both analytical and numerical models. Then we compare model results for the Milky Way, Dwarf Irregulars, Quasars and the Intra-Cluster- Medium with abundances derived from emission lines. These comparisons allow us to put strong constraints on the stellar nucleosynthesis and the mechanisms of galaxy formation.

Francesca Matteucci

2007-04-05

307

Bactericidal oncocin derivatives with superior serum stabilities.  

PubMed

The proline-rich antimicrobial peptide oncocin is remarkably active in vitro against a number of important Gram-negative bacteria of concern to humans owing to their increasing resistance to antibiotics, i.e. Enterobacteriaceae (Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae) and non-fermenting species (Acinetobacter baumannii and Pseudomonas aeruginosa). Degradation of oncocin in mouse serum was investigated in this study. Several approaches to stabilise the main cleavage sites (C-terminal to Arg-15 and N-terminal to Arg-19) by substituting either or both arginine (Arg) residues with non-proteinogenic amino acids, i.e. ?-amino-3-guanidino-propionic acid, homoarginine, nitro-arginine, N-methyl-arginine, ?-homoarginine, D-arginine (D-Arg) or ornithine (Orn), were tested. These modifications were found to increase the half-life of oncocin in full mouse serum. For oncocin with two Orn residues in positions 15 and 19, the half-life in full serum increased from 25 min to 3 h. An increase of >8 h was observed for oncocin with two D-Arg residues at these same positions. The antibacterial activities of these modified sequences were slightly better than the original oncocin sequence. Moreover, the three most stable analogues were found to be bactericidal against E. coli and were not toxic to HeLa cells or haemolytic to human erythrocytes. PMID:21185160

Knappe, Daniel; Kabankov, Natalja; Hoffmann, Ralf

2011-02-01

308

Pregabalin serum levels in apprehended drivers.  

PubMed

Pregabalin is a medicinal drug used mainly for the treatment of epilepsy and neuropathic pain. It has been shown to possess an abuse potential and in recent years some reports of illegal use have been published. In order to further evaluate the extent and nature of pregabalin abuse, serum pregabalin levels of drivers apprehended for driving under the influence of drugs (DUID) in Finland in 2012 were assessed. The samples were analysed by an LC-MS/MS system and the results were evaluated in relation to the typical therapeutic range of pregabalin as well as the age and gender of the driver. Pregabalin was detected in 206 samples in the study period. The median (range) serum concentration was 6.2 (0.68-111.6)mg/L. In nearly 50% of the cases the serum concentration was above the typical therapeutic range. In most of the cases the driver had also taken other drugs besides pregabalin, the mean number of concomitantly taken drugs being four. Our data indicate that pregabalin is being used at high doses, probably for recreational purposes. The vast majority of the drivers positive for pregabalin in our study material had used pregabalin as a part of a spectrum of psycho-active drugs and thus qualified as probable drug abusers. In these cases pregabalin probably contributed to their driving impairment but to what extent remained unclear in this study. PMID:25072779

Kriikku, Pirkko; Wilhelm, Lars; Rintatalo, Janne; Hurme, Jukka; Kramer, Jan; Ojanperä, Ilkka

2014-10-01

309

Lake Michigan fish consumption as a source of polychlorinated biphenyls in human cord serum, maternal serum, and milk  

Microsoft Academic Search

Reported consumption of Lake Michigan sport fish was examined in relation to the levels of polychlorinated biphenyls (PCBs) in biological samples provided by a sample of maternity patients. Fish consumption was correlated with PCB levels in maternal serum and milk but not in cord serum. PCB levels in serum increased with age, but were unrelated to social class, parity, or

P. M. Schwartz; S. W. Jacobson; G. Fein; J. L. Jacobson; H. A. Price

1983-01-01

310

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

311

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

312

Hematology and serum chemistry of captive juvenile double-crested cormorants (Phalacrocorax auritus).  

PubMed

Hematologic and serum chemical values were obtained for double-crested cormorants (Phalacrocorax auritus) to improve clinical diagnosis of disease in this species. Blood samples were collected from 20 captive double-crested cormorants at 4 to 6 weeks of age. Hematocrit and leukocyte concentrations were determined in heparinized blood. Concentrations of sodium, potassium, chloride, bicarbonate, calcium, phosphorus, creatinine, glucose, uric acid, total protein, and albumin, and the activity levels of alkaline phosphatase, creatinine kinase, and aspartate aminotransferase were determined in serum. Total leukocyte concentrations in these double-crested cormorants were higher than the limited ranges reported for cormorants of other species, possibly due to subclinical infection with the liver trematode Amphimerus elongatus, and to differences in species and age. PMID:10416069

Kuiken, T; Danesik, K L

1999-07-01

313

Stevioside enhances apoptosis induced by serum deprivation in PC12 cells.  

PubMed

In the laboratory, using a PC12 cell system, studies have been conducted on the effects of various chemicals on apoptosis, as it is considered to be an essential part of normal development, maintenance, and defense in organisms. Stevioside is a natural sweetener extracted from the leaves of Stevia rebaudiana. Since it is widely used as a sugar replacement, it was decided to evaluate the toxicological effects of low concentrations of stevioside on apoptosis induced by serum deprivation using the PC12 cell system. It was found that based on data from DNA electrophoresis and TUNEL signal assays stevioside enhanced apoptosis induced by serum deprivation. This enhancement was caused by increased expression of Bax and of cytochrome c released into the cytosol. These findings suggest that stevioside affects the regulation of the normal apoptotic condition. Further investigation will be needed to clarify the detailed mechanism of the enhancement due to the treatment with stevioside. PMID:22316388

Takahashi, Kumiko; Sun, Yongkun; Yanagiuchi, Ikumi; Hosokawa, Toshiyuki; Saito, Takeshi; Komori, Miyako; Okino, Tatsufumi; Kurasaki, Masaaki

2012-05-01

314

Hematology and serum chemistry of captive juvenile double-crested cormorants (Phalacrocorax auritus).  

PubMed Central

Hematologic and serum chemical values were obtained for double-crested cormorants (Phalacrocorax auritus) to improve clinical diagnosis of disease in this species. Blood samples were collected from 20 captive double-crested cormorants at 4 to 6 weeks of age. Hematocrit and leukocyte concentrations were determined in heparinized blood. Concentrations of sodium, potassium, chloride, bicarbonate, calcium, phosphorus, creatinine, glucose, uric acid, total protein, and albumin, and the activity levels of alkaline phosphatase, creatinine kinase, and aspartate aminotransferase were determined in serum. Total leukocyte concentrations in these double-crested cormorants were higher than the limited ranges reported for cormorants of other species, possibly due to subclinical infection with the liver trematode Amphimerus elongatus, and to differences in species and age. Images Figure 1. PMID:10416069

Kuiken, T; Danesik, K L

1999-01-01

315

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

316

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

317

Improved gastric emptying in diabetic rats by irbesartan via decreased serum leptin and ameliorated gastric microcirculation.  

PubMed

Diabetic gastroparesis (DG) is a common clinical complication of diabetes mellitus. Leptin may cause delayed gastric emptying in the central and peripheral pathways. Microcirculatory disturbances in the stomach make gastric smooth muscles and nerves hypoxic-ischemic, thereby impairing gastric motility. Irbesartan is an angiotensin II (ATII) receptor blocker that indirectly decreases serum leptin levels and improves blood vessel endothelia. This study examined the effect of irbesartan on DG and its relationship with serum leptin levels and microcirculatory disturbances of the stomach. Sprague-Dawley rats were injected with streptozotocin to induce diabetes and were then treated with or without 0.012 g·kg(-1)·d(-1) irbesartan by gavage. After six weeks of treatment, the gastric evacuation rate (GER) was measured using phenol red. Serum leptin levels were detected using enzyme-linked immunosorbent assays. Endothelin (ET) in the stomach tissue was examined using a radioimmunoassay, whereas chemical colorimetry was used to measure the nitric oxide synthase (NOS) activity of stomach tissues. The mRNA expression of the ATII receptor (AT1R) was assessed using reverse transcription-polymerase chain reaction. Treatment with irbesartan significantly increased the GER of diabetic rats and reduced the serum leptin levels, as well as decreased the ET content and AT1R mRNA expression in the stomach (P<0.05). Changes in the cNOS activity after irbesartan intervention were not significant (P>0.05), whereas iNOS activity was significantly decreased (P<0.05). Irbesartan can alleviate hyperglycemia-induced delayed gastric emptying, which is associated with decreased serum leptin levels and improved microcirculation in the stomach. PMID:25222222

He, L; Sun, Y; Zhu, Y; Ren, R; Zhang, Y; Wang, F

2014-01-01

318

Serum Cystatin C as a Marker of Renal Function in Critically Ill Patients With Normal Serum Creatinine  

PubMed Central

Background: Serum creatinine as a classic marker of renal function has several limitations in the detection of renal dysfunction. Objectives: This study assessed the validity of serum cystatin C as a marker of renal function in critically ill patients with normal serum creatinine. Patients and Methods: Eighty adult patients referred to intensive care units with serum creatinine levels < 1.5 mg/dL and without hemodynamic instability were chosen and their serum creatinine and cystatin C levels were measured. A 24-hour urine sample was collected to calculate creatinine clearance (Ccr). Renal dysfunction was defined as Ccr < 80 mL/min/1.73 m2. Results: There were significant correlations between measured Ccr and 1/serum creatinine (R = 0.51, P < 0.001) and 1/serum cystatin C (R = 0.25, P = 0.028). The difference between false negative rates of serum creatinine (93.33%) and cystatin C (80%) in the detection of renal dysfunction was significant (P = 0.032). Receiver operating characteristic curve analysis illustrated that area under the curve of serum creatinine and cystatin C for detecting renal dysfunction were 0.711 and 0.607, respectively; however, this difference was not significant (P = 0.222). Conclusions: Our data demonstrated that serum cystatin C is not superior to serum creatinine in the early detection of renal dysfunction in critically ill patients. PMID:24783172

Sagheb, Mohammad Mahdi; Namazi, Soha; Geramizadeh, Bita; Karimzadeh, Amin; Oghazian, Mohammad Bagher; Karimzadeh, Iman

2014-01-01

319

Is Thymoglobulin or Rituximab the Cause of This Serum Sickness? A Case Report of Serum Sickness Dilemma and Literature Review  

PubMed Central

Serum sickness is an immune-complex-mediated systemic illness that can occur after treatment with monoclonal or polyclonal antibodies such as Rituxan (Rituximab) or antithymocyte globulin (Thymoglobulin), respectively. Since Rituximab is now being used as an adjuvant treatment for acute humoral rejection and its prevalence to cause serum sickness is comparable to Thymoglobulin-associated serum sickness (20% versus 27%), it should be considered a potential cause of serum sickness after rejection treatment. In kidney transplant patients, there are no case reports where patient received both Thymoglobulin and Rituximab before developing serum sickness. We are reporting a patient who developed serum sickness after receiving Thymoglobulin and Rituximab that led us to consider Rituximab as one of the potential causes in this patient's serum sickness. Since diagnosis of serum sickness is clinical, and Rituximab use has expanded into treatment of glomerulonephritis and acute humoral rejection, it should be considered as a potential offender of serum sickness in these patient populations. There are not any evidence-based guidelines or published clinical trials to help guide therapy for antibody-induced serum sickness; however, we successfully treated our case with three doses of Methylprednisone 500?mg intravenously. Further studies are needed to evaluate Rituximab-associated serum sickness in nephrology population to find effective treatment options. PMID:23056053

Sandhu, Amarpreet; Harford, Antonia; Singh, Pooja; Alas, Eduardo

2012-01-01

320

Modulation of the expression of the VIP receptor by serum factors on the human melanoma cell line IGR39.  

PubMed

IGR39 cells, isolated from a human superficial melanoma, display at their surface high and low affinity receptors for the vasoactive intestinal peptide (VIP). When grown in DME medium supplemented with 10% fetal calf serum, cells display 1.6 x 10(5) high affinity (Kd 0.74 nM) and 5.6 x 10(5) low affinity (Kd 55 nM) VIP binding sites per cell. When cultured in a chemically defined medium containing EGF, transferrin, and selenium, IGR39 cells display many neurite-like extensions. Following these morphological changes, the specific [125I]VIP binding is increased four- to fivefold after 6 days in culture. This phenomenon is reversible and is the result of an increased number of VIP binding sites available at the cell surface, without modification of their affinities. The molecular mass of the binding sites is also unchanged whatever cell culture conditions. Increase in [125I]VIP binding is inversely correlated to the serum concentration in the culture medium. When added to the chemically defined medium, sera from various origins as well as some serum substitutes reduce [125I]VIP binding to the same extent as that of the serum. The total cAMP production by VIP-stimulated IGR39 cells is enhanced by a factor of six to seven when cells are cultured in serum-free medium, in good correlation with the increase of VIP binding capacity. These data suggest that factor(s) present in fetal calf serum inhibit(s) the expression of VIP receptor, thus demonstrating the importance of a strict control of cell culture conditions for in vitro studies. PMID:1314189

Bellan, C; Fabre, C; Secchi, J; Marvaldi, J; Pichon, J; Luis, J

1992-05-01

321

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

322

Isolation and Characterization of Human Dental Pulp Derived Stem Cells by Using Media Containing Low Human Serum Percentage as Clinical Grade Substitutes for Bovine Serum  

PubMed Central

Adult stem cells have been proposed as an alternative to embryonic stem cells to study multilineage differentiation in vitro and to use in therapy. Current culture media for isolation and expansion of adult stem cells require the use of large amounts of animal sera, but animal-derived culture reagents give rise to some questions due to the real possibility of infections and severe immune reactions. For these reasons a clinical grade substitute to animal sera is needed. We tested the isolation, proliferation, morphology, stemness related marker expression, and osteoblastic differentiation potential of Dental Pulp Stem Cells (DPSC) in a chemically defined medium containing a low percentage of human serum, 1.25%, in comparison to a medium containing 10% Fetal Bovine Serum (FBS). DPSCs cultured in presence of our isolation/proliferation medium added with low HS percentage were obtained without immune-selection methods and showed high uniformity in the expression of stem cell markers, proliferated at higher rate, and demonstrated comparable osteoblastic potential with respect to DPSCs cultured in 10% FBS. In this study we demonstrated that a chemically defined medium added with low HS percentage, derived from autologous and heterologous sources, could be a valid substitute to FBS-containing media and should be helpful for adult stem cells clinical application. PMID:23155430

Beltrami, Antonio Paolo; Cesselli, Daniela; Curcio, Francesco

2012-01-01

323

Serum galectin-3 level in systemic sclerosis.  

PubMed

Systemic sclerosis (SSc) is an autoimmune disease of unknown etiology characterized by progressive fibrosis. Activated fibroblasts are mainly responsible for fibrosis in SSc. Galectin-3, a ?-galactoside-binding lectin, plays many important regulatory roles in both physiological and pathological processes including proliferation, apoptosis, inflammation, and fibrosis. The purpose of this study was to assess the serum galectin-3 levels in patients with SSc. Thirty-seven SSc patients, 23 systemic lupus erythematosus (SLE) patients (serving as patient control group), and 28 healthy volunteers were enrolled in this study. Disease activity and severity scores were detected with Valentini disease activity index and Medsger disease severity scale in the SSc group and SLE disease activity index and Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index in the SLE group. The serum levels of galectin-3, vascular endothelial growth factor, transforming growth factor-?, and interleukin-6 were determined. Compared to the control group, the galectin-3 levels were higher in the SSc and SLE groups. The galectin-3 levels were not correlated with the disease activity and severity indexes in both patient groups. But, the serum galectin-3 levels were higher in the active SSc and SLE subgroups than in the inactive SSc (4.6?±?5.8 vs. 1.3?±?1.1 ng/ml, p?=?0.015) and SLE (17.4?±?11.3 vs. 6.5?±?8.9 ng/ml, p?=?0.019) subgroups. These results suggest that galectin-3, which is associated with fibrosis and inflammation by previous studies, may be a prominent biomarker of disease activity in SSc. PMID:23912642

Koca, Suleyman Serdar; Akbas, Fatma; Ozgen, Metin; Yolbas, Servet; Ilhan, Nevin; Gundogdu, Baris; Isik, Ahmet

2014-02-01

324

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...

325

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

326

Radioimmunoassays for the serum thymic factor (FTS)  

SciTech Connect

This patent describes a radioimmunoassay of serum thymic factor (FTS) in a test sample, comprising: (a) contacting a first aliquot of the sample with anti-FTS antibody, with a known amount of FTS hormone standard and a known amount of radiolabeled FTS analogue; and (b) contacting a second aliquot of the sample with anti-FTS antibody and a known amount of radiolabeled FTS analogue; and (c) measuring the radioactivity of the antigen-antibody complex in each aliquot; and (d) calculating the amount of FTS in the test sample.

Erickson, B.W.; Fok, K.F.; Incefy, G.S.; Ohga, K.

1987-01-06

327

Enzyme-linked immunosorbent assay to quantitate serum ferritin in black and white ruffed lemurs (Varecia variegata variegata).  

PubMed

Lemurs in captivity progressively accumulate iron deposits in a variety of organs (hemosiderosis) including duodenum, liver, and spleen throughout their lives. When excessive, the toxic effects of intracellular iron on parenchymal cells, particularly the liver, can result in clinical disease and death. The pathogenesis of excessive iron storage in these species has been attributed to dietary factors related to diets commonly fed in captivity. Tissue iron stores can be directly estimated by tissue biopsy and histologic examination, or quantitated by chemical analysis of biopsy tissue, However, expense and risk associated with anesthesia and surgery prevent routine use of tissue biopsy to assess iron status. A noninvasive means of assessing total body iron stores is needed to monitor iron stores in lemurs to determine whether dietary modification is preventing excessive iron deposition, and to monitor potential therapies such as phlebotomy or chelation. Serum ferritin concentration correlates with tissue iron stores in humans, horses, calves, dogs, cats, and pigs. Serum ferritin is considered the best serum analyte to predict total body iron stores in these species and is more reliable than serum iron or total iron binding capacity, both of which may be affected by disorders unrelated to iron adequacy or excess including hypoproteinemia, chronic infection, hemolytic anemia, hypothyroidism, renal disease, and drug administration. We have developed an enzyme-linked immunosorbent assay to measure serum ferritin in lemurs. The assay uses polyclonal rabbit anti-human ferritin antibodies in a sandwich arrangement. Ferritin isolated from liver and spleen of a black and white ruffed lemur (Varecia variegata variegata) was used as a standard. Ferritin standards were linear from 0 to 50 microg/L. Recovery of purified ferritin from lemur serum varied from 95% to 110%. The within-assay variability was 4.5%, and the assay-to-assay variability for three different samples ranged from 10% to 17%. The assay also measures serum ferritin in several other lemur species. PMID:17312722

Andrews, Gordon A; Chavey, Patricia Sue; Crawford, Graham

2005-12-01

328

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

329

Evaluation of ammonia as diluent for serum sample preparation and determination of selenium by graphite furnace atomic absorption spectrometry*1  

NASA Astrophysics Data System (ADS)

A method for the determination of total selenium in serum samples by graphite furnace atomic absorption spectrometry was evaluated. The method involved direct introduction of 1:5 diluted serum samples (1% v/v NH 4OH+0.05% w/v Triton X-100 ®) into transversely heated graphite tubes, and the use of 10 ?g Pd+3 ?g Mg(NO 3) 2 as chemical modifier. Optimization of the modifier mass and the atomization temperature was conducted by simultaneously varying such parameters and evaluating both the integrated absorbance and the peak height/peak area ratio. The latter allowed the selection of compromise conditions rendering good sensitivity and adequate analyte peak profiles. A characteristic mass of 49 pg and a detection limit (3s) of 6 ?g 1 -1 Se, corresponding to 30 ?g l -1 Se in the serum sample, were obtained. The analyte addition technique was used for calibration. The accuracy was assessed by the determination of total selenium in Seronorm™ Trace Elements Serum Batch 116 (Nycomed Pharma AS). The method was applied for the determination of total selenium in ten serum samples taken from individuals with no known physical affection. The selenium concentration ranged between 79 and 147 ?g l -1, with a mean value of 114±22 ?g l -1.

Hernández-Caraballo, Edwin A.; Burguera, Marcela; Burguera, José L.

2002-12-01

330

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.

331

STUDIES ON THE TRANSFERRINS OF ADULT SERUM, CORD SERUM, AND CEREBROSPINAL FLUID: THE EFFECT OF NEURAMINIDASE  

Microsoft Academic Search

Recent population studies by starch gel electrophoresis have revealed an elaborate genetically determined polymorphism of human and primate trans- ferrin, the iron-binding protein in serum. At the present time twelve different molecular species of human transferrin have been identified (1). Transferrins whose electrophoretic mobilities are faster than the common type C are labeled B, and slower moving variants are labeled

W. CARRY PARKER; ALEXANDER G. BEAR

1962-01-01

332

Blood groups, serum cholesterol, serum uric acid, blood pressure, and obesity in adolescents.  

PubMed Central

To assess the association of blood groups with coronary risk factors, data were examined from the third cycle of the National Health Examination Survey. In a nationwide sample of more than 6000 black and white adolescents aged 12 to 17 years, ABO blood group, haptoglobin phenotype, selected other genetic markers of blood and secretions, and coronary risk factor levels were measured. Blood group A1 was associated with significantly higher serum total cholesterol levels in white females independent of multiple potential confounders, in white males independent of age and weight, and in southern black females independent of age and weight. ABO blood group was not significantly associated with blood pressure, resting heart rate, or subscapular skinfold thickness. An association with serum uric acid in white males was not independent of weight. In white males only, haptoglobin phenotype 2-2 was associated with significantly higher serum cholesterol levels than 1-1 or 2-1 adjusting for age and weight. No consistent associations were found between Rh types, ABH secretor ability, or group-specific component types and risk factors. This analysis of national data confirms previously reported associations of blood group A with higher serum total cholesterol levels in white adults and adolescents. PMID:1956079

Gillum, R. F.

1991-01-01

333

Serum PDGF-AB in pleural mesothelioma.  

PubMed

Overexpression of platelet-derived growth factor (PDGF) has been observed in lung and pleural tumors. The aim of this study was to evaluate the diagnostic and prognostic role of serum PDGF in pleural mesothelioma (PM). Four groups of subjects were studied: 93 malignant PM patients, 33 primary non small cell lung cancer patients, 51 subjects exposed to asbestos, defined as high-risk controls, and 24 healthy controls. PDGF-AB mean concentration was higher in PM patients (45.8 ng/ml) than in high-risk controls (33.1 ng/ml) and healthy controls (26.8 ng/ml). Using the cut-off level of 49.8 ng/ml, corresponding to the mean+2SD of PDGF-AB in healthy controls, 43% of PM patients showed positive PDGF-AB levels. Survival was evaluated in 82 PM patients. At the end of the follow-up (median 9.8 months) 80.5% of patients had died. Median survival was 13.1 and 7.9 months for patients with PDGF-AB lower and higher than the cut-off, respectively. Adjusting for age, sex, histology and platelet count, positive PDGF-AB levels were associated with lower survival (OR=1.2, 95%CI: 0.9-1.6), even if not significantly so. In conclusion, serum PDGF may represent a useful additional parameter to prognostic factors already available for PM. PMID:16103743

Filiberti, Rosa; Marroni, Paola; Neri, Monica; Ardizzoni, Andrea; Betta, Pier Giacomo; Cafferata, Mara A; Canessa, Pier Aldo; Puntoni, Riccardo; Ivaldi, Giovanni Paolo; Paganuzzi, Michela

2005-01-01

334

Serum complement pattern in essential mixed cryoglobulinaemia.  

PubMed Central

In twenty-six patients affected by essential cryoglobulinaemia, 188 determinations of serum complement components (SCC) were made. A peculiar pattern was observed which was characterized by: (a) low levels of early components (Clq, Cls and C4), (b) normal levels of C3 and high concentrations of late components (C5, C9) and (c) CH50 values significantly lower than normal. No relationship could be observed between early SCC and C3 levels. Thirty-three crossed immunoelectrophoreses were performed in thirteen patient's blood samples. The C3c peaks were not different from normal. Follow-up data (156 serum samples from twenty-four patients) during a 6-40 month period showed a non-homogeneous SCC behaviour. However, no relationship was found between the complement concentrations and clinical score. These findings suggest that SCC abnormalities are related to a complement hyposynthesis, which could be caused by a reduced C2 production or by a negative feedback effect of active components or their fragments. Images FIG. 2 FIG. 3 PMID:668194

Tarantino, A; Anelli, A; Costantino, A; De Vecchi, A; Monti, G; Massaro, L

1978-01-01

335

Metabolic syndrome: soybean foods and serum lipids.  

PubMed Central

Metabolic syndrome is a cluster of coronary heart disease (CHD) risk factors of which central obesity, insulin resistance, increased triglycerides/decreased HDL cholesterol, and hypertension are major cardiovascular risk factors. The educational objectives of this review are to describe hypocholesteromic effects from soybean foods. Early Italian observations indicated that isolated soy protein lowered total cholesterol, especially the LDL component, in humans with elevated serum lipids. Whole soybeans, with their major phytoestrogen inflavones (genistein, daidzein, and glycetin) intact, are known to decrease both total and LDL cholesterol. Major early reviews, meta-analyses, and clinical trials in hyperlipidemic humans indicate a predictable range of decreases in serum lipids: total cholesterol (10-19%), LDL cholesterol (14-20%), and triglycerides (8-14%). Recent, large, randomized trials in postmenopausal women indicated that a soy protein component induces significant increases in HDL cholesterol. Therapy for metabolic syndrome must first be patient education, especially for predominant U.S. minority groups (Afro-, Latino-, and Native Americans). The four major preventive health educational facts necessary to reduce CHD/metabolic syndrome must now recognize that whole soybeans are abundant sources of: 1) vegetable protein, 2) high soluble fiber content, 3) virtual absence of saturated fat, though high in polyunsaturated fats, and 4) major phytoestrogens. PMID:15303407

Merritt, John C.

2004-01-01

336

Kinetics of serum aminosalicylic acid levels  

PubMed Central

A mathematical model, involving three consecutive first order reactions, has been applied to already existing experimental material in order to explain the hourly variation in serum levels obtained after administration of varying repeated doses of different preparations of p-aminosalicylic acid to human volunteers. The model closely agrees with the experimental data for all the orally administered preparations concerned, and the differences in blood levels for different preparations can be explained in terms of the values attributed to the parameters involved in the model. The same model adequately describes the elimination of aminosalicylic acid from the blood after a single intravenous infusion provided that the initial blood level attained does not exceed about 11 mg/100 ml., but fails at higher values. In the latter instance a second order model gives a good fit to the experimental curves. The increase in serum levels found experimentally for the same subjects during the first weeks of prolonged treatment with phenyl-p-aminosalicylate corresponds to a change in the values of the parameters for the elimination from the blood only. PMID:14206266

Engberg-Pedersen, H.; Mørch, P.; Tybring, L.

1964-01-01

337

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

338

Design of a serum stability tag for bioactive peptides.  

PubMed

Serum has a high intrinsic proteolytic activity that leads to continuous processing of peptides and proteins. Strategies to protect bioactive peptides from serum proteolytic degradation include incorporation of unnatural amino acids, conformational constraints, large polymeric tags, or other synthetic manipulations such as amide bond replacements. Here we explored a possibility of designing a serum stability tag made of natural amino acids. We observed that a diproline motif (-Pro-Pro-) shows remarkable stability against serum endopeptidases. Accordingly, we designed close to 50 peptides to identify natural amino acids flanking the -Pro-Pro- sequence that can enhance the serum stability of this motif. As a result, a tetrapeptide with the sequence Asp-Pro-Pro-Glu (DPPE) was identified that remains intact in human serum for more than 24 h. at 37°C. PMID:24354769

Jambunathan, Kalyani; Galande, Amit K

2014-01-01

339

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

340

Serum prolactin and cortisol levels in evaluation of pseudoepileptic seizures.  

PubMed

In 6 patients with epilepsy, a twofold increase in serum prolactin levels followed true epileptic seizures, but no significant change followed pseudoepileptic attacks in 6 other patients. Serum prolactin concentration is a useful biochemical marker to distinguish between epileptic and pseudoepileptic seizures. Serum cortisol levels also increased after epileptic seizures, but diurnal and individual variations render the cortisol level a less reliable indicator of such attacks. PMID:4037754

Pritchard, P B; Wannamaker, B B; Sagel, J; Daniel, C M

1985-07-01

341

Serum IgG subclasses in autoimmune diseases.  

PubMed

To characterize serum IgG subclass levels in several autoimmune diseases, including primary Sjogren syndrome (pSS), systemic sclerosis (SSc), systemic lupus erythematosus (SLE), and primary biliary cirrhosis (PBC). We aimed to analyze serum IgG subclass distribution and to test whether serum IgG4 levels are elevated in these diseases.Serum IgG subclass levels from 102 pSS, 102 SSc, 100 SLE, and 59 PBC patients, as well as 40 healthy controls (HCs), were measured using the immunonephelometric assay. The distribution of IgG subclasses among these autoimmune diseases was analyzed.In this cross-sectional study, serum IgG1 (IgG1/IgG) and/or IgG3 (IgG3/IgG) were significantly increased, compared with those in HCs. Only 6.34% of patients had levels of serum IgG4 >135?mg/dL. There were no significant differences in the frequency of elevated serum IgG4 levels between patients and HC. In pSS, serum IgG1 levels were much higher than those in other disease groups, whereas serum IgG2 and IgG3 levels were most prominently increased in PBC.A strikingly different serum IgG subclass distribution was detected in patients with autoimmune diseases compared with HCs. Serum IgG subclass levels also showed distinct characteristics among different autoimmune diseases. Serum IgG4 levels in these patients were lower or not much higher than those in HCs, which differed from IgG4-related diseases. PMID:25590841

Zhang, Haoze; Li, Ping; Wu, Di; Xu, Dong; Hou, Yong; Wang, Qian; Li, Mengtao; Li, Yongzhe; Zeng, Xiaofeng; Zhang, Fengchun; Shi, Qun

2015-01-01

342

Effects of psychological stress on serum iron and erythropoiesis  

Microsoft Academic Search

There are about one billion patients with iron deficiency anaemia all over the world. Recently, researchers have reported\\u000a successively that stress can cause decrease of serum iron, in consistent with our studies showing that heat exposure and acceleration\\u000a stress led to significant decrease of serum iron in rats. However, so far whether pure psychological stress can cause decrease\\u000a of serum

Chunlan Wei; Jian Zhou; Xueqiang Huang; Min Li

2008-01-01

343

Serum bactericidal activity against Helicobacter pylori in patients with hypogammaglobulinaemia  

PubMed Central

The two major primary antibody deficiency disorders are X-linked hypogammaglobulinaemia (XLA) and common variable immunodeficiency (CVID). CVID patients have an elevated risk for gastric cancer and extra-nodal marginal zone lymphoma. Both diseases are associated with Helicobacter pylori infection. We investigated whether antibody deficiency leads to defective serum bactericidal activity against H. pylori. We also investigated the correlation with immunoglobulin (Ig)M levels and observed the terminal complement complex (TCC) activity. Sera of 13 CVID patients (four H. pylori positive), one patient with hyper-IgM syndrome, one patient with Good syndrome (both H. pylori positive), five XLA patients, four H. pylori seropositive controls, four H. pylori seronegative controls and a sample of pooled human serum (PHS) were incubated in vitro with bacterial suspensions of H. pylori for 30 min. After 72 h of culture, colony-forming units were counted. TCC formation was measured by enzyme-linked immunosorbent assay. We found that normal human serum is bactericidal for H. pylori, whereas heat-inactivated serum shows hardly any killing of H. pylori. Serum (1%) of hypogammaglobulinaemia patients has a decreased bactericidal activity against H. pylori. Helicobacter pylori-positive (HP+) normal individuals show more than 90% killing of H. pylori, whereas CVID patients show 35% killing (P = 0·007) and XLA patients only 19% (P = 0·003). Serum (1%) of HP+ volunteers showed significantly better killing compared with serum of H. pylori-negative (HP–) volunteers (P = 0·034). No correlation between (substituted) IgG levels and serum bactericidal activity was found, but a weak correlation between total serum IgM and serum bactericidal activity was found. In conclusion, serum bactericidal activity against H. pylori is decreased in patients with hypogammaglobulinaemia. Heat treatment of the serum abolished the bactericidal capacity, indicating that complement activity is essential for the bactericidal effect. PMID:19438595

Desar, I M E; van Deuren, M; Sprong, T; Jansen, J B M J; Namavar, F; Vandenbroucke-Grauls, C M; van der Meer, J W M

2009-01-01

344

Farm animal serum proteomics and impact on human health.  

PubMed

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

Di Girolamo, Francesco; D'Amato, Alfonsina; Lante, Isabella; Signore, Fabrizio; Muraca, Marta; Putignani, Lorenza

2014-01-01

345

DIAGNOSTIC POTENTIAL OF SERUM PROTEOMIC PATTERNS IN PROSTATE CANCER  

Microsoft Academic Search

Purpose: The serum prostate specific antigen test has been widely used in the last decade as an effective screening tool for prostate cancer (CaP). However, the high false-positive rate of the serum prostate specific antigen test necessitates the development of more accurate diagnostic and prognostic biomarkers for CaP. Promising diagnostic potential of serum protein patterns detected by surface enhanced laser

LIONEL L. BANEZ; PREMKALA PRASANNA; LEON SUN; AMINA ALI; ZHIQIANG ZOU; BAO-LING ADAM; DAVID G. MCLEOD; JUDD W. MOUL; SHIV SRIVASTAVA

2003-01-01

346

Investigation of the health status of Michigan chemical corporation employees.  

PubMed

Clinical findings are reported for a group of 55 employees of the Michigan Chemical Corporation which manufactured FireMaster BP-6 from 1970 to 1974, in addition to a variety of other halogenated fire retardant chemicals. The results are compared with those from a group of male farm residents and consumers from Michigan examined at the same time. An increased prevalence of chest and skin symptoms was observed, compared with farmers. Skin symptoms were more prevalent among former PBB production personnel. Musculosketal symptoms were less prevalent among these workers than among farmers. Serum PBB concentrations are signicantly higher than among farmers. Blood chemistry results were similar for workers and farmers. However, both groups exhibited a significantly higher prevalence of elevated liver function tests (SGOT, SPGT) than a control population of nonexposed farmers. Both farmers and chemical workers showed an association of elevated CEA with serum PBB greater than 10 ppb. PMID:209974

Anderson, H A; Wolff, M S; Fischbein, A; Selikoff, I J

1978-04-01

347

Immunoglobulin G antibodies directed against protein III block killing of serum-resistant Neisseria gonorrhoeae by immune serum  

PubMed Central

Neisseria gonorrhoeae that resist complement-dependent killing by normal human serum (NHS) are sometimes killed by immune convalescent serum from patients recovering from disseminated gonococcal infection (DGI). In these studies, killing by immune serum was prevented or blocked by IgG isolated from NHS. Purified human IgG antibodies directed against gonococcal protein III, an antigenically conserved outer membrane protein, contained most of the blocking activity in IgG. Antibodies specific for gonococcal porin (protein I), the major outer membrane protein, displayed no blocking function. In separate experiments, immune convalescent DGI serum which did not exhibit bactericidal activity was restored to killing by selective depletion of protein III antibodies by immunoabsorption. These studies indicate that protein III antibodies in normal and immune human serum play a role in serum resistance of N. gonorrhoeae. PMID:3095479

1986-01-01

348

The nature of human serum insulin-like activity (ILA): characterization of ILA in serum and serum fractions obtained by acid-ethanol extraction and adsorption chromatography  

PubMed Central

Studies were undertaken in an attempt to clarify the apparent heterogeneous nature of human serum insulin-like activity. Methods of preparative zone electrophoresis on Pevikon, acid-ethanol extraction of trichloroacetic acid serum protein precipitates, adsorption chromatography on DEAE-cellulose and Dowex 50, gel filtration chromatography, and insulin antiserum immunoreactivity were used. The results establish the presence of a substance in serum with in vitro biological properties similar to insuln but with different physicochemical properties. The major portion of serum ILA measured by bioassay techniques can be attributed to the effects of this substance. Whereas the in vitro biological effects of this substance on muscle and adipose cells were similar to those of crystalline insulin, the substance is distinguished from insulin by: (1) the failure of insulin antiserum to inhibit its in vitro biological effect; (2) a slower electrophoretic mobility (in the gamma-beta globulin zone); and (3) a larger molecular weight, between 40,000 and 50,000 in these studies. It is similar to insulin since both are soluble in acid-ethanol. The results further indicate that previously described insulin-like activity in gamma-beta globulin preparations, the major portion of total serum insulin activity described in acid-ethanol extracts of serum, “bound” insulin, “atypical” insulin, and antibody nonsuppressible insulin-like activity bioassayed in diluted serum are all one and the same substance. PMID:4170389

Poffenbarger, Philip L.; Ensinck, John W.; Hepp, Dieter K.; Williams, Robert H.

1968-01-01

349

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

350

Nongradient blue native gel analysis of serum proteins and in-gel detection of serum esterase activities.  

PubMed

The objective of the present study was to analyze serum protein complexes and detect serum esterase activities using nongradient blue native polyacrylamide gel electrophoresis (BN-PAGE). For analysis of potential protein complexes, serum from rat was used. Results demonstrate that a total of 8 gel bands could be clearly distinguished after Coomassie blue staining, and serum albumin could be isolated nearly as a pure protein. Moreover, proteins in these bands were identified by electrospray mass spectrometry and low-energy collision induced dissociation (CID)-MS/MS peptide sequencing and the existence of serum dihydrolipoamide dehydrogenase (DLDH) was confirmed. For studies of in-gel detection of esterase activities, serum from rat, mouse, and human was used. In-gel staining of esterase activity was achieved by the use of either ?-naphthylacetate or ?-naphthylacetate in the presence of Fast blue BB salt. There were three bands exhibiting esterase activities in the serum of both rat and mouse. In contrast, there was only one band showing esterase activity staining in the human serum. When serum samples were treated with varying concentrations of urea, esterase activity staining was abolished for all the bands except the one containing esterase 1 (Es1) protein that is known to be a single polypeptide enzyme, indicating that majority of these esterases were protein complexes or multimeric proteins. We also identified the human serum esterase as butyrylcholinesterase following isolation and partial purification using ammonium sulfate fractioning and ion exchange column chromatographies. Where applicable, demonstrations of the gel-based method for measuring serum esterase activities under physiological or pathophysiological conditions were illustrated. Results of the present study demonstrate that nongradient BN-PAGE can serve as a feasible analytical tool for proteomic and enzymatic analysis of serum proteins. PMID:21237726

Thangthaeng, Nopporn; Sumien, Nathalie; Forster, Michael J; Shah, Ruchir A; Yan, Liang-Jun

2011-02-15

351

Evaluation of neural gene expression in serum treated embryonic stem cells in Alzheimer's patients  

PubMed Central

Background: Previous studies confirmed that neural gene expression in embryonic stem cells (ESC) could influence by chemical compounds through stimulating apoptotic pathway. We aimed to use ESCs-derived neural cells by embryoid body formation as an in vitro model for determination of neural gene expression changes in groups that treated by sera from Alzheimer's patients and compare with healthy individuals. Materials and Methods: ESC line which was derived from the C57BL/6 mouse strain was used throughout this study. ESC-derived neural cells were treated with serum from Alzheimer's patient and healthy individual. Neural gene expression was assessed in both groups by quantitative real-time polymerase chain reaction analysis. The data was analyzed by SPSS Software (version 18). Results: Morphologically, the reducing in neurite out-growth was observed in neural cells in group, which treated by serum from Alzheimer's patient, while neurite growth was natural in appearance in control group. Microtubule-associated protein 2 and glial fibrillary acidic protein expression significantly reduced in the Alzheimer's patient group compared with the control group. Nestin expression did not significantly differ among the groups. Conclusion: Neural gene expression could be reduced in serum treated ESC in Alzheimer's patients. PMID:23961278

Dehghani, Leila; Hashemi-Beni, Batool; Poorazizi, Elahe; Khorvash, Fariborz; Shaygannejad, Vahid; Sedghi, Maryam; Vesal, Sahar; Meamar, Rokhsareh

2013-01-01

352

Nature's chemicals and synthetic chemicals: Comparative toxicology  

Microsoft Academic Search

The toxicology of synthetic chemicals is compared to that of natural chemicals, which represent the vast bulk of the chemicals to which humans are exposed. It is argued that animals have a broad array of inducible general defenses to combat the changing array of toxic chemicals in plant food (nature's pesticides) and that these defenses are effective against both natural

B. N. Ames; M. Profet; L. S. Gold

1990-01-01

353

Chemical Accelerators The phrase "chemical accelerators"  

E-print Network

Meetings 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 by one of us for devices that produce beams of chemically interesting species at relative kinetic

Zare, Richard N.

354

Chemical information science coverage in Chemical Abstracts.  

PubMed

For many years Chemical Abstracts has included in its coverage publications on chemical documentation or chemical information science. Although the bulk of those publications can be found in section 20 of Chemical Abstracts, many relevant articles were found scattered among 39 other sections of CA in 1984-1985. In addition to the scattering of references in CA, the comprehensiveness of Chemical Abstracts as a secondary source for chemical information science is called into question. Data are provided on the journals that contributed the most references on chemical information science and on the languages of publication of relevant articles. PMID:3558505

Wiggins, G

1987-02-01

355

SERUM PROLACTIN CHANGES IN EPILEPSY AND HYSTERIA  

PubMed Central

SUMMARY The usefulness of post-ictal serum prolactin changes, as an adjunct, in the differentiation of generalized tonic-clonic seizures and complex partial seizures from hysterical pseudoepileptic seizures, was investigated in a double blind study designed to control for variables known to alter prolactin levels. Significant post-ictal hyper-prolactinemia, with a peak at 20 minutes and a fall towards baseline by 1 hour, was found after complex partial seizures, generalized tonic-clonic seizures and after bilateral, unmodified ECT, but not after hysterical pseudoepileptic seizures or in stressed, non-epileptic controls. A proportionate increase in peak prolactin levels of at least thrice baseline values was found to best differentiate genuine seizures from pseudoepileptic seizures. Postictal hyperprolactinemia is a sensitive biochemical marker of a genuine seizure and of potential use in the differentiation of epileptic from hysterical pseudoepileptic seizures. PMID:21927300

Tharyan, P.; Kuruvilla, K.; Prabhakar, S.

1988-01-01

356

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

357

Serum cholesterol levels and postoperative atrial fibrillation  

PubMed Central

Background Post-operative atrial fibrillation is an important complication after coronary bypass surgery. As inflammation and oxidative stress were makedly encountered in the etiology, high cholesterol was also defined to provoke atrial fibrillation. In this present study, the relationship between postoperative atrial fibrillation and preoperative serum lipid levels were evaluated. Methods A total of 100 patients, who were operated at the department of Cardiovascular Surgery of our hospital were included to the study analysis. Patients, who had preoperative atrial fibrillation, thyroid dysfunction, or left atrial dilatation (above 4.5 cm) were excluded from the study. Patients were divided into two groups with postoperative atrial fibrillation development (Group I n?=?36), and without atrial fibrillation development (Group II n?=?64). Preoperative routine blood analyses, ECG, echocardiography were evaluated. Patients were followed for atrial fibrillation development for one month starting from the intensive care unit at the postoperative period. Serum lipid profiles and thyroid function were measured. For homogenization of inflammatory factors and oxidative stress, treatments other than statins, betablockers, calcium channel blockers, aspirin, ACE inhibitors, and ARB were stopped for 10 days. Atrial fibrillation for at least ?5 minutes in the intensive care unit was accepted as postoperative atrial fibrillation. Results Demographic data were similiar between groups (p?>?0.05). There was no difference in TC levels between groups, whereas LDL-C levels were statistically lower in patients developing post-operative atrial fibrillation (106.67?±?28.36 vs 118.75?±?27.75; P?

2014-01-01

358

Titanium preferential binding sites in human serum transferrin at physiological concentrations.  

PubMed

Serum transferrin (Tf) is an iron binding glycoprotein that plays a central role in the metabolism of this essential metal but it also binds other metal ions. Four main transferrin forms containing different iron binding states can be distinguished in human serum samples: monoferric (C-site or N-site), holotransferrin (with two Fe atoms) and apotransferrin (with no metal). Recently, it has been reported that Tf binds also Ti even more tightly than does Fe, in artificially Ti(iv) spiked solutions. However, very limited work has been done on the Ti binding to Tf at physiological concentrations in patients carrying intramedullary Ti nails. Here we report the chemical association of Ti to Tf "in vivo" under different chromatographic conditions by elemental mass spectrometry using double focusing inductively coupled plasma (DF-ICP-MS) as detector. For the separation of the Ti/Fe-Tf forms different gradient conditions have been explored. The observed results reveal that human serum Ti (from patients carrying intramedullary Ti nails) is uniquely associated to the N-lobe of Tf. The investigation of the influence of sialic acid in the carbohydrate chain of human serum Tf, studied by incubating the protein with neuraminidase (sialidase) to obtain the monosialilated species, revealed that the binding affinity of Ti was similar for monosialo-Tf and for native-Tf and occurs in the N-lobe. These results suggest that the species Fe(C)Ti(N)-TF might provide a route for Ti entry into cells via the transferrin receptors after the release of the metal from its implants. PMID:22041858

Nuevo-Ordoñez, Yoana; Montes-Bayón, M; Blanco González, E; Sanz-Medel, A

2011-12-01

359

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

360

Apolipoprotein LI is the trypanosome lytic factor of human serum  

Microsoft Academic Search

Human sleeping sickness in east Africa is caused by the parasite Trypanosoma brucei rhodesiense. The basis of this pathology is the resistance of these parasites to lysis by normal human serum (NHS). Resistance to NHS is conferred by a gene that encodes a truncated form of the variant surface glycoprotein termed serum resistance associated protein (SRA). We show that SRA

Luc Vanhamme; Françoise Paturiaux-Hanocq; Philippe Poelvoorde; Derek P. Nolan; Laurence Lins; Jan Van Den Abbeele; Annette Pays; Patricia Tebabi; Huang Van Xong; Alain Jacquet; Nicole Moguilevsky; Marc Dieu; John P. Kane; Patrick De Baetselier; Robert Brasseur; Etienne Pays

2003-01-01

361

Serum 25-Hydroxyvitamin D Levels and Risk of Multiple Sclerosis  

Microsoft Academic Search

Design, Setting, and Participants Prospective, nested case-control study among more than 7 million US military personnel who have serum samples stored in the De- partment of Defense Serum Repository. Multiple sclerosis cases were identified through Army and Navy physical disability databases for 1992 through 2004, and diagnoses were confirmed by medical record review. Each case (n=257) was matched to 2

Kassandra L. Munger; Lynn I. Levin; Bruce W. Hollis; Noel S. Howard; Alberto Ascherio

2006-01-01

362

The depression of the immune response by serum protein fractions  

PubMed Central

A number of serum protein fractions were tested for their ability to suppress the immune response of rats injected with washed sheep cells. Significant depression of the immune response was produced by human serum proteins, and by bovine ?-globulin fractions. The mechanism of this effect is at present not clear. ImagesFIG. 2 PMID:4162433

Sims, F. H.; Freeman, Jean W.

1966-01-01

363

Copper intrauterine contraceptive devices and serum essential metals  

Microsoft Academic Search

Serum levels of the essential metals, iron (Fe), copper (Cu), magnesium (Mg), zinc (Zn), and calcium (Ca), were determined by atomic absorption spectrophotometry in one hundred and twenty randomly selected adult Nigerian female volunteers fitted with copper T or Delta T intrauterine contraceptive devices (IUDs) for a period of 3–18 months, and their normal age-matched controls. The mean serum concentration

S. O. Ayangade; O. O. Oyelola

1988-01-01

364

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

365

Serum Microarrays for Large Scale Screening of Protein Levels  

Microsoft Academic Search

There is a great need for comprehensive proteomic anal- ysis of large patient cohorts of plasma and serum samples to identify biomarkers of human diseases. Here we de- scribe a new antibody-based proteomic approach involv- ing a reverse array format where serum samples are spot- ted on a microarray. This enables all samples to be screened for their content of

Magdalena Janzi; Jenny Odling; Qiang Pan-Hammarstrom; Mårten Sundberg; Joakim Lundeberg; Mathias Uhlen; Lennart Hammarstrom; Peter Nilsson

2005-01-01

366

Daily rhythm of salivary and serum urea concentration in sheep  

PubMed Central

Background In domestic animals many biochemical and physiological processes exhibit daily rhythmicity. The aim of the present study was to investigate the rhythmic pattern of salivary and serum urea concentrations in sheep. Methods Six 3-year-old female sheep kept in the same environmental conditions were used. Sheep were sampled at 4 hour intervals for 48 consecutive hours starting at 08:00 of the first day and finishing at 04:00 of the second day. Blood samples were collected via intravenous cannulae inserted into the jugular vein; saliva samples were collected through a specific tube, the "Salivette". Salivary and serum urea concentrations were assayed by means of UV spectrophotometer. ANOVA was used to determine significant differences. The single Cosinor procedure was applied to the results showing significant differences over time. Results ANOVA showed a significant effect of time on salivary and serum urea concentrations. Serum and salivary urea peaked during the light phase. In the dark phase serum and salivary urea concentrations decreased, and the diurnal trough occurred at midnight. Cosinor analysis showed diurnal acrophases for salivary and serum urea concentrations. Daily mean levels were significantly higher in the serum than in the saliva. Conclusion In sheep both salivary and serum urea concentrations showed daily fluctuations. Urea is synthesized in the liver and its production is strongly influenced by food intake. Future investigation should clarify whether daily urea rhythms in sheep are endogenous or are simply the result of the temporal administration of food. PMID:17123442

Piccione, Giuseppe; Foà, Augusto; Bertolucci, Cristiano; Caola, Giovanni

2006-01-01

367

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

368

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

369

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

370

Prolongation and enhancement of serum methotrexate concentrations by probenecid  

Microsoft Academic Search

The disappearance of methotrexate (MTX) from the serum after an intravenous bolus injection and intravenous infusion was studied over 24 hours in eight and four patients respectively. Probenecid given at the same time as the bolus injection delayed the disappearance of MTX from the serum and resulted in enhanced concentrations throughout the 24 hours studied. At 24 hours the mean

G W Aherne; E Piall; V Marks; G Mould; W F White

1978-01-01

371

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...

372

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

373

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

374

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

375

SERUM ALBUMIN POLYMORPHISMS IN NATURAL AND LABORATORY POPULATIONS OF PEROMYSCUS  

E-print Network

SERUM ALBUMIN POLYMORPHISMS IN NATURAL AND LABORATORY POPULATIONS OF PEROMYSCUS JAMES H. BROWN AND CARL F. WELSER ABSTRACT.-Electrophoresisof serum from 14 species of Peromyscus revealed albumin populations of small mammals in general, and of Peromyscus in particular, has largely been ne- glected

Brown, James H.

376

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...

377

Postdialytic Rebound of Serum Phosphorus: Pathogenetic and Clinical Insights  

Microsoft Academic Search

To gain insights into postdialytic rebound of serum phosphate (PDR-P), serum phosphate (P), calcium (Ca), and parathyroid hormone (PTH), levels were compared from the end of treatment (T0) to the subsequent 30 to 120 min and up to 68 hr in uremic patients who underwent with crossover modality a single session of two dialytic treatments character- ized by different convective

ROBERTO MINUTOLO; VINCENZO BELLIZZI; MARIO CIOFFI; CARMELA IODICE; PAOLO GIANNATTASIO; MICHELE ANDREUCCI; VINCENZO TERRACCIANO; BIAGIO R. DI IORIO; GIUSEPPE CONTE; LUCA DE NICOLA

2002-01-01

378

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

379

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

380

A Survey of Membrane Proteins in Human Serum  

PubMed Central

Serum and membrane proteins are two of the most attractive targets for proteomic analysis. Previous membrane protein studies tend to focus on tissue sample, while membrane protein studies in serum are still limited. In this study, an analysis of membrane proteins in normal human serum was carried out. Nano-liquid chromatography-electrospray ionization mass spectrometry (NanoLC-ESI-MS/MS) and bioinformatics tools were used to identify membrane proteins. Two hundred and seventeen membrane proteins were detected in the human serum, of which 129 membrane proteins have at least one transmembrane domain (TMD). Further characterizations of identified membrane proteins including their subcellular distributions, molecular weights, post translational modifications, transmembrane domains and average of hydrophobicity, were also implemented. Our results showed the potential of membrane proteins in serum for diagnosis and treatment of diseases. PMID:25288886

Dung, Nguyen Tien; Van Chi, Phan

2012-01-01

381

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 serum sample is vortex-mixed with a solution of mobile phase for tetracyclines and 2% (v/v) phosphoric acid. The mixture is filtered using a 30,000 molecular weight cutoff microseparation tube which separates high-molecular-weight solutes following low-speed centrifugation. Tetracyclines are separated from other serum components by reverse phase liquid chromatography (LC) with buffered methanol mobile phase. Ultraviolet absorbance of the column effluent is monitored at 267 nm. Concentrations as low as 0.2 micrograms/mL of tetracyclines in serum are quantitatable, with recoveries from 76.2 to 102.6% and coefficients of variation from 2.69 to 5.36%. The method has been tested in bovine, porcine, equine, caprine, ovine, canine, feline, and avian (turkey) serum. PMID:3771447

Tyczkowska, K; Aronson, A L

1986-01-01

382

Detection of oxidation in human serum lipoproteins  

E-print Network

-TOF-MS. Observed variations in the mass spectra include m/z shifts due to chemical modifications and change in isoform distributions. The oxidation procedure and analysis techniques were applied to a clinical application to study the effects of table grape...

Myers, Christine Lee

2006-04-12

383

Biomonitoring Hexamethylene Diisocyanate (HDI) Exposure Based on Serum Levels of HDI-Specific IgG  

PubMed Central

Objectives: Isocyanate chemicals essential for polyurethane production are widely used industrially, and are increasingly found in consumer products. Asthma and other adverse health effects of isocyanates are well-documented and exposure surveillance is crucial to disease prevention. Hexamethylene diisocyanate (HDI)-specific serum immunoglobulin G (IgG) was evaluated as an exposure biomarker among workers at a US Air Force Air Logistics Center, which includes a large aircraft maintenance facility. Methods: HDI-specific IgG (HDI-IgG) titers in serum samples (n = 74) were measured using an enzyme-linked immunosorbent assay based upon the biuret form of HDI conjugated to human albumin. Information on personal protective equipment (PPE), work location/tasks, smoking, asthma history, basic demographics, and HDI skin exposure was obtained through questionnaire. Results: HDI-specific serum IgG levels were elevated in n = 17 (23%) of the workers studied. The prevalence and/or end-titer of the HDI-IgG was significantly (P < 0.05) associated with specific job titles, self-reported skin exposure, night-shift work, and respirator use, but not atopy, asthma, or other demographic information. The highest titers were localized to specific worksites (C-130 painting), while other worksites (generator painting) had no or few workers with detectable HDI-IgG. Conclusions: HDI-specific immune responses (IgG) provide a practical biomarker to aid in exposure surveillance and ongoing industrial hygiene efforts. The strategy may supplement current air sampling approaches, which do not assess exposures via skin, or variability in PPE use or effectiveness. The approach may also be applicable to evaluating isocyanate exposures in other settings, and may extend to other chemical allergens. PMID:22449630

Wisnewski, Adam V.; Stowe, Meredith H.; Nerlinger, Abby; Opare-addo, Paul; Decamp, David; Kleinsmith, Christopher R.; Redlich, Carrie A.

2012-01-01

384

Serum copper concentration as an index of clinical lung injury  

SciTech Connect

The purpose of this ongoing study is to determine whether thoracic radiotherapy for lung cancer produces an early increase in serum copper (Cu) concentration, an increase which might predict clinical outcome. Copper and iron concentrations were measured in serum obtained from nonsmall cell lung cancer patients at 0, 1, 2, 4, and 6 weeks after the start of radiotherapy. Control groups included patients irradiated for breast cancer (low dose of radiation to the lung), for endometrial, cervical or prostatic cancer, and patients with congestive heart failure, pulmonary hypertension, chronic obstructive pulmonary disease (COPD), and cutaneous burns with or without smoke inhalation. Serum Cu concentration increased at least 10 micrograms/dl from the pretreatment level in approximately 75% of the adenocarcinoma and squamous cell lung cancer patients, but in only 1 of 4 undifferentiated lung cancer cases. In virtually all of these responders, serum Cu increased to a maximum at 2 weeks after the start of therapy, then plateaued or decreased slightly despite continuing irradiation. Within the subset of squamous cell lung cancers, there was a direct correlation between the degree of histologic differentiation and both baseline serum Cu concentration and the probability of an early increase therein. In contrast, only 33% of breast cancer patients and 15% of endometrial, cervical and prostate cancer patients exhibited an increase in serum Cu concentration at 2 weeks after the start of radiotherapy. Serum Cu concentration was within normal limits in virtually all patients with congestive heart failure, pulmonary hypertension, and COPD. Burn patients exhibited a significant reduction in serum Cu, although concomitant smoke inhalation increased serum Cu back to low-normal levels. Serum iron concentration did not change significantly in any category of patients.

Molteni, A.; Ward, W.F.; Kim, Y.T.; Shetty, R.; Brizio-Molteni, L.; Giura, R.; Ribner, H.; Lomont, M. (Northwestern Univ. Medical School, Chicago, IL (USA))

1989-01-01

385

Serum Myostatin Is Reduced in Individuals with Metabolic Syndrome  

PubMed Central

Aims Myostatin is a negative regulator of skeletal muscle mass and may also modulate energy metabolism secondarily. We aim to investigate the relationship between serum myostatin and the metabolic variables in diabetic (DM) and non-diabetic subjects. Materials and Methods A cross-sectional study recruiting 246 consecutive DM patients and 82 age- and gender-matched non-diabetic individuals at a medical center was conducted. The variables of anthropometry and blood chemistry were obtained. Serum myostatin level was measured with enzyme immunoassay. Results DM group had lower serum myostatin compared with non-diabetics (7.82 versus 9.28 ng/ml, p<0.01). Sixty-two percent of the recruited individuals had metabolic syndrome (MetS). The patients with MetS had significantly lower serum myostatin than those without (7.39 versus 9.49 ng/ml, p<0.001). The serum myostatin level decreased with increasing numbers of the MetS components (p for trend<0.001). The patients with higher body mass index, larger abdominal girth, lower high-density lipoprotein cholesterol (HDL-C), and higher triglycerides had lower serum myostatin than those without. The serum myostatin level was independently negatively related to larger abdominal girth, higher triglycerides, and lower HDL-C after adjustment. The odds ratios for MetS, central obesity, low HDL-C, high triglycerides, and DM were 0.85, 0.88, 0.89, 0.85, and 0.92, respectively, when serum myostatin increased per 1 ng/mL, in the binary logistic regression models. Conclusions Lower serum myostatin independently associated with MetS, central obesity, low HDL-C, and high triglycerides after adjustment. Higher serum myostatin is associated with favorable metabolic profiles. PMID:25254550

Chiang, Chih-Kang; Tseng, Fen-Yu; Tseng, Ping-Huei; Chen, Chi-Ling; Wu, Kwan-Dun; Yang, Wei-Shiung

2014-01-01

386

Early effects of erythropoietin on serum hepcidin and serum iron bioavailability in healthy volunteers.  

PubMed

Hepcidin regulates plasma iron bioavailability and subsequently iron availability for erythropoiesis. rHuEPO has been reported to decrease hepcidin expression in case of repeated subcutaneous injections. Thus, hepcidin level measurement could be a candidate marker for detection of rHuEPO abuse. However, when used for doping, rHuEPO can be injected intravenously and the scheme of injection is unknown. Our aim was to evaluate the early effects of a single intravenous rHuEPO injection on serum hepcidin levels. Fourteen male healthy volunteers received one intravenous injection of 50 U/Kg of rHuEPO during a placebo-controlled, randomized, double-blind, cross-over study. Serum hepcidin, quantified by a competitive ELISA method and iron parameters was then evaluated for 24 h. Serum levels of hepcidin were significantly increased 4 h after rHuEPO injection when compared with placebo injection (78.3 ± 55.5 vs. 57.5 ± 34.6 ng/ml, respectively; +36%, p < 0.05), whereas iron and transferrin saturation dramatically decreased 12 h after rHuEPO injection when compared with placebo injection (9.2 ± 3.5 vs. 15.8 ± 4.2 ?g/l, respectively; -42%, p < 0.05 and 14.8 ± 5.0 vs. 26.3 ± 6.4%, respectively; -44%, p < 0.05). In addition, 12 and 24 h after rHuEPO injection serum hepcidin levels were lower compared with placebo injection (41.6 ± 27.4 vs. 56.6 ± 28.1 ng/ml after 12 h; -27%, p < 0.05 and 26.0 ± 29.6 vs. 81.2 ± 29.4 ng/ml after 24 h; -68%, p < 0.05). Intravenous injection of recombinant EPO induces a precocious and transient increase of serum hepcidin leading to a transient decrease of iron bioavailability. The transitory increase and dynamics of its concentration make difficult the practical use of hepcidin to detect rHuEPO doping. PMID:21818622

Lainé, Fabrice; Laviolle, Bruno; Ropert, Martine; Bouguen, Guillaume; Morcet, Jeff; Hamon, Catherine; Massart, Catherine; Westermann, Mark; Deugnier, Yves; Loréal, Olivier

2012-04-01

387

Effects of Graded Levels of Bentonite on Serum Clinical Profiles, Metabolic Hormones, and Serum Swainsonine Concentrations in Lambs Fed Locoweed (Oxytropis sericea)  

Microsoft Academic Search

samples were collected 1, 2, 4, and 8 h after feeding. Weekly blood samples were analyzed for serum clinical chemistry profiles, and additional blood sam- ples collected on d 35 were analyzed for serum metabolic hormones and serum swainsonine concen- trations. Within 1 wk, serum alkaline phosphatase and glutamic oxaloacetic transaminase activities in- creased markedly (P < .05) in lambs

G. D. Pulsipher; M. L. Galyean; D. M. Hallford; G. S. Smith; D. E. Kiehl

2010-01-01

388

Serum cystatin C is superior to serum creatinine as a marker of kidney function: A meta-analysis  

Microsoft Academic Search

Background: Serum cystatin C (Cys C) has been proposed as a simple, accurate, and rapid endogenous marker of glomerular filtration rate (GFR) in research and clinical practice. However, there are conflicting reports regarding the superiority of Cys C over serum creatinine (Cr), with a few studies suggesting no significant difference. Methods: We performed a meta-analysis of available data from various

Vikas R. Dharnidharka; Charles Kwon; Gary Stevens

2002-01-01

389

Hematology, Serum Chemistry, and Serum Protein Electrophoresis Ranges for Free-ranging Roe Deer (Capreolus capreolus) in Sweden.  

PubMed

Abstract We present the first reference ranges for hematology (n?=?35 animals), serum biochemistry (n?=?62), and serum protein electrophoresis (n?=?32) in physically restrained free-ranging roe deer (Capreolus capreolus). Animals were captured in box traps and physically restrained for blood sampling during the winter in Sweden, 2011-13. No clinically significant sex or age differences were found. PMID:25375949

Küker, Susanne; Huber, Nikolaus; Evans, Alina; Kjellander, Petter; Bergvall, Ulrika A; Jones, Krista L; Arnemo, Jon M

2015-01-01

390

Proteolytic components of serum IgG preparations  

PubMed Central

Chemical catalysis, an effector mechanism utilized by fully assembled antibodies, can also be mediated by the isolated antibody subunits. Because trace amounts of free light chains (L chains) are present in IgG preparations, a detailed study was undertaken to identify the constituents responsible for the polyreactive proteolytic activity of IgG purified from human sera, determined as the extent of cleavage of the model peptide substrate Pro-Phe-Arg-methylcoumarinamide. Two proteolytic species with approximate mass of 50 kD and 150 kD were separated by repetitive gel filtration in a denaturing solvent (6 m guanidine hydrochloride). The activity of the renatured 50-kD fraction (in fluorescence units/?g protein) was more than 45-fold greater than of the 150-kD fraction. Both fractions lost the activity following immunoadsorption on immobilized anti-IgG antibody. Fab fragments prepared from the 150-kD IgG fraction retained the activity. Reducing and non-reducing SDS-electrophoresis suggested the 50-kD fraction isolated from the IgG preparations to be a mixture of heavy chain (H chain) monomers and disulphide bonded L chain dimers. Electrophoretically homogeneous monomers of 50-kD H chains and 25-kD L chains were prepared by gel filtration of reduced and alkylated IgG from seven human subjects. Each of the alkylated L chain preparations displayed the proteolytic activity. The activity in alkylated H chains was undetectable or only marginally greater than the background values. L chain dimers appear to be the major species responsible for the polyreactive proteolytic activity of serum IgG preparations, with a smaller contribution furnished by tetrameric IgG. PMID:10792374

Li, L; Kalaga, R; Paul, S

2000-01-01

391

75 FR 20771 - Viruses, Serums, Toxins, and Analogous Products and Patent Term Restoration; Nonsubstantive...  

Federal Register 2010, 2011, 2012, 2013, 2014

...124 [Docket No. APHIS-2009-0069] Viruses, Serums, Toxins, and Analogous Products...SUMMARY: We are amending the Virus-Serum-Toxin Act regulations concerning...contain provisions implementing the Virus-Serum-Toxin Act, as amended...

2010-04-21

392

21 CFR 866.5700 - Whole human plasma or serum immunological test system.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 false Whole human plasma or serum immunological test system...Test Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system...

2011-04-01

393

21 CFR 866.5700 - Whole human plasma or serum immunological test system.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 false Whole human plasma or serum immunological test system...Test Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system...

2012-04-01

394

21 CFR 866.5700 - Whole human plasma or serum immunological test system.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 false Whole human plasma or serum immunological test system...Test Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system...

2013-04-01

395

21 CFR 866.5700 - Whole human plasma or serum immunological test system.  

Code of Federal Regulations, 2014 CFR

... 2014-04-01 false Whole human plasma or serum immunological test system...Test Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system...

2014-04-01

396

21 CFR 866.5700 - Whole human plasma or serum immunological test system.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 false Whole human plasma or serum immunological test system...Test Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system...

2010-04-01

397

Serum metabolomics analysis reveals impaired lipid metabolism in rats after oral exposure to benzo(a)pyrene.  

PubMed

Benzo(a)pyrene [B(a)P] is ubiquitous in the environment. Although multiple toxicities have been reported for B(a)P, the impact of exposure to this chemical on metabolic networks remains obscure. In this study, a metabolomics approach based on ultra-high-performance liquid chromatography/mass spectrometry was used to investigate the disruption of global serum metabolic profiles in rats caused by exposure to B(a)P. Sprague-Dawley rats were treated with oral doses of 10, 100 and 1000 ?g kg(-1) B(a)P for 32 consecutive days. Distinct serum metabolomic profiles were associated with these doses. Twelve metabolites were identified as potential biomarkers and indicated that exposure to B(a)P disrupted both global amino acid metabolism and lipid metabolism, especially phospholipid and sphingolipid metabolism. Serum levels of lysophosphatidylcholines showed dose-dependent decreases, whereas serum levels of sphingomyelins showed dose-dependent increases. The expressions of some key genes involved in these pathways were also investigated. Expressions of enpp2, sms and smpd were significantly altered by exposure to high doses of B(a)P. Metabolic biomarkers were more sensitive than the corresponding gene expression for exposure to B(a)P. The findings of this study suggest potential novel mechanisms for the identified metabolic pathways. PMID:25490995

Wang, Xiaoxue; Zhang, Jie; Huang, Qingyu; Alamdar, Ambreen; Tian, Meiping; Liu, Liangpo; Shen, Heqing

2014-12-10

398

Flavonoid binding to human serum albumin.  

PubMed

Dietary flavonoid may have beneficial effects in the prevention of chronic diseases. However, flavonoid bioavailability is often poor probably due to their interaction with plasma proteins. Here, the affinity of daidzein and daidzein metabolites as well as of genistein, naringenin, and quercetin for human serum albumin (HSA) has been assessed in the absence and presence of oleate. Values of the dissociation equilibrium constant (K) for binding of flavonoids and related metabolites to Sudlow's site I range between 3.3x10(-6) and 3.9x10(-5)M, at pH 7.0 and 20.0 degrees C, indicating that these flavonoids are mainly bound to HSA in vivo. Values of K increase (i.e., the flavonoid affinity decreases) in the presence of saturating amounts of oleate by about two folds. Present data indicate a novel role of fatty acids as allosteric inhibitors of flavonoid bioavailability, and appear to be relevant in rationalizing the interference between dietary compounds, food supplements, and drugs. PMID:20599706

Bolli, Alessandro; Marino, Maria; Rimbach, Gerald; Fanali, Gabriella; Fasano, Mauro; Ascenzi, Paolo

2010-07-30

399

Serum laminin, hydrocarbon exposure, and glomerular damage.  

PubMed

It has been postulated that occupational exposure to hydrocarbons may damage the kidney and lead to glomerulonephritis and chronic renal failure. As laminin is a ubiquitous basement membrane component that seems to play a central part in the structure and function of basement membranes and as the normal renal filtration process is highly dependent on an intact glomerular basement membrane, the serum laminin concentration was examined in a population of workers exposed to hydrocarbons. The hydrocarbon exposure was assessed by exposure surrogates (exposure duration and exposure score). An interaction between occupational exposure to hydrocarbons and hypertension increased the laminin concentration whereas the laminin concentration decreased in workers exposed for a long time probably because of a selection effect. In a subgroup of printers exposed to toluene whose hippuric acid excretion had been recorded for several years this interaction was confirmed when the hippuric acid excretion was substituted for the other exposure indices. In the exposed group, the age-related decline in creatinine clearance was accelerated. These results seem to confirm that occupational exposure to hydrocarbons is a non-specific factor that may promote a deterioration of renal function. PMID:8280641

Hotz, P; Thielemans, N; Bernard, A; Gutzwiller, F; Lauwerys, R

1993-12-01

400

Serum laminin, hydrocarbon exposure, and glomerular damage.  

PubMed Central

It has been postulated that occupational exposure to hydrocarbons may damage the kidney and lead to glomerulonephritis and chronic renal failure. As laminin is a ubiquitous basement membrane component that seems to play a central part in the structure and function of basement membranes and as the normal renal filtration process is highly dependent on an intact glomerular basement membrane, the serum laminin concentration was examined in a population of workers exposed to hydrocarbons. The hydrocarbon exposure was assessed by exposure surrogates (exposure duration and exposure score). An interaction between occupational exposure to hydrocarbons and hypertension increased the laminin concentration whereas the laminin concentration decreased in workers exposed for a long time probably because of a selection effect. In a subgroup of printers exposed to toluene whose hippuric acid excretion had been recorded for several years this interaction was confirmed when the hippuric acid excretion was substituted for the other exposure indices. In the exposed group, the age-related decline in creatinine clearance was accelerated. These results seem to confirm that occupational exposure to hydrocarbons is a non-specific factor that may promote a deterioration of renal function. PMID:8280641

Hotz, P; Thielemans, N; Bernard, A; Gutzwiller, F; Lauwerys, R

1993-01-01

401

Diagnosing and managing low serum testosterone.  

PubMed

Measuring testosterone levels became easier in the 1970s, and it wasn't long before levels were being checked in men across all age groups. At that time, several authors reported an age-associated decline of serum testosterone levels beginning in the fourth or fifth decades of life. Other studies found that the decline in testosterone with age might be more related to comorbidities that develop in many aging men. Aggressive marketing campaigns by pharmaceutical companies have led to increased awareness of this topic, and primary care physicians are seeing more patients who are concerned about "low T." Unfortunately, testosterone replacement therapy has not been straightforward. Many men with low testosterone levels have no symptoms, and many men with symptoms who receive treatment and reach goal testosterone levels have no improvement in their symptoms. The actual prevalence of hypogonadism has been estimated to be 39% in men aged 45 years or older presenting to primary care offices in the United States. As the US population ages, this number is likely to increase. This article, targeted to primary care physicians, reviews the concept of late-onset hypogonadism, describes how to determine the patients who might benefit from therapy, and offers recommendations regarding the workup and initiation of treatment. PMID:25484498

Rivas, Ana Marcella; Mulkey, Zachary; Lado-Abeal, Joaquin; Yarbrough, Shannon

2014-10-01

402

[Prenatal serum screening for Down's syndrome].  

PubMed

With the aid of two commercially available analysis programmes we effected non-invasive assessment of the risk for Down's syndrome in 597 pregnancies with healthy fetuses and in 22 pregnancies with trisomie 21-affected fetuses, maternal age ranging between 18 and 45 years. Based on the women's serum levels, hormone concentrations of AFP, free estriol and beta HCG were determined, a multiple of their median was combined with the age factor, and the result used as a parameter for overall risk estimation. A risk cut-off-level greater then 1:250 was considered to represent a positive risk. For patients younger than 35 years test sensitivity, at just over 50%, was found to be low. For those aged 35 years or greater, however, the Dermalog programme was able to detect 94.4% and the Alpha programme 88.2% of fetuses affected by trisomy 21, with a false-positive rate of 19.6 and 19.1%, respectively. If the test were to be applied to all pregnant women beyond 35 years of age the detection rate of Down's syndrome could be nearly doubled compared to today's figure (only 50%, of women in this age group undergo amniocentesis). By the same token the rate of amniocentesis-induced abortion (approx. 1%) could be reduced to about one third. PMID:1379769

Müller, U; Benz, R; Krahner-Pilat, M; Terinde, R

1992-01-01

403

Control of declared origin of bovine serum, a pilot study  

NASA Astrophysics Data System (ADS)

Bovine serum is the essential culture medium for cell cultures. Therefore it is highly demanded and the quality of the serum, e.g.: absence of bacteria, viruses certain antibodies, etc.., are important criteria. as some cattle diseases are endemic in certain regions, the origin of bovine serum is an important quality measure for its value. Thus the need to control the declared origins is present. Bovine serum was measured for d2H, d13C, d15N and d34S of proteine (dry residue) and d2H and d18O of the serum water. The hydrogen and oxygen are mainly depending by the isotopic composition of the water ingested by the cattle, and thus usually influenced by the isotopic signal of the precipitation. The carbon isotope signal is reflecting the diet of the cattle, whether it mainly feed on C3- or C4-plants. The nitrogen and sulphur isotope ratio is transferred from the ground/soil into the plant material and into the animal tissue, with some offset for nitrogen and without any significant offset for sulphur. Bovine serum samples from Canada, USA, Mexico, Brazil, Australia and New Zealand have been analysed. Due to the variations in the environmental conditions in different countries and regions which influence the isotope signatures of the serum samples it is possible to discriminate samples of different origin. Main discriminating parameters are d2H and d18O, d13C and d34S.

Horacek, M.; Papesch, W.

2009-04-01

404

Fatty acyltranferases in serum in cystic fibrosis (CF) patients  

SciTech Connect

Studies on serum and gastrointestinal secretion from CF patient is suggest that defective accumulation of mucus in gastrointestinal tract and excessive amount of a protease resistant peptides in serum are related to the abnormal activity of enzymes responsible for fatty acylation of proteins. Here, the authors investigated the fatty acyltransferase activities in serum of normal and CF patients. A 15 l of serum was mixed with 0.85 nmol ( UC)palmitoyl CoA, 200 g of serine and threonine and incubated at 37C for 30 min. The incubates were immediately frozen, dried extracted with C/M and chromatographed in chloroform/methanol/water. The incorporation of ( UC)palmitate was determined using linear radioscanner and authoradiography. The results of HPTLC revealed that CF serum in addition of ACAT and LCAT contained enzymes responsible for the transfer of ( UC)palmitate to monoacylphosphoglycerides, and serine and threonine. In normal serum the formation of a small amount of palmitoyl serine and palmitoyl threonine was also observed but the acylation of monoacylphosphoglycerides was not detectable. The authors conclude that in cystic fibrosis the abnormal fatty acyltransferases are responsible for the occurrence of protease resistant glycoprotein, unusual peptides in serum and possibly for the modification of membrane proteins and lipids.

Zielenski, J.; Newman, L.J.; Slomiany, B.L.; Slomiany, A.

1987-05-01

405

Serum Immunoglobulins in Patients with Iron Deficiency Anemia  

PubMed Central

Iron deficiency is a common cause of anemia worldwide. Documentation shows that these patients have impaired immunity and are prone to infections. The aim of this study was to confirm whether serum immunoglobulins change in adult nonpregnant females with iron deficiency anemia. Based on patients’ clinical history, CBC results, and serum ferritin, iron and total iron binding capacity, 45 healthy patients and 45 iron deficiency anemia (hypochrom microcytic) patients were entered into this case–control study. Serum IgG, IgA and IgM were measured in patient and control groups using the nephelometry method. Both of the groups were compared using suitable statistical test. Mean serum values of IgG, IgA and IgM in the patient group were 12.47 ± 7.67, 1.93 ± 0.92 and 1.35 ± 0.90 g/l respectively. Mean serum values for the control group were 12.51 ± 6.85, 2.14 ± 0.88 and 1.49 ± 0.73 g/l respectively. Although serum immunoglobulins were slightly lower in the patient group compared to the control group these differences were not significant with the t test. Our study showed serum immunoglobulin levels did not change in iron deficiency anemia. PMID:21629635

Sadeghian, Mohammad Hadi; Ayatollahi, Hossein; Manavifar, Lida; Enaiati, Hoda; Mahmoudi, Masoumeh

2010-01-01

406

Increased Serum Oxidative Stress Markers in Women with Uterine Leiomyoma  

PubMed Central

Background Uterine leiomyomas (fibroids) are the most common gynaecological benign tumors in premenopausal women. Evidences support the role of oxidative stress in the development of uterine leiomyoma. We have analysed oxidative stress markers (thiols, advanced oxidized protein products (AOPP), protein carbonyls and nitrates/nitrites) in preoperative sera from women with histologically proven uterine leiomyoma. Methodology/Principal Findings We conducted a laboratory study in a tertiary-care university hospital. Fifty-nine women with histologically proven uterine leiomyoma and ninety-two leiomyoma-free control women have been enrolled in this study. Complete surgical exploration of the abdominopelvic cavity was performed in each patient. Preoperative serum samples were obtained from all study participants to assay serum thiols, AOPP, protein carbonyls and nitrates/nitrites. Concentrations of serum protein carbonyl groups and AOPP were higher in leiomyoma patients than in the control group (p=0.005 and p<0.001, respectively). By contrast, serum thiol levels were lower in leiomyoma patients (p<0.001). We found positive correlations between serum AOPP concentrations and total fibroids weight (r=0.339; p=0.028), serum AOPP and serum protein carbonyls with duration of infertility (r=0.762; p=0.006 and r=0.683; p=0.021, respectively). Conclusions/Significance This study, for the first time, reveals a significant increase of protein oxidative stress status and reduced antioxidant capacity in sera from women with uterine leiomyoma. PMID:23951284

Santulli, Pietro; Borghese, Bruno; Lemaréchal, Herve; Leconte, Mahaut; Millischer, Anne-Elodie; Batteux, Frédéric

2013-01-01

407

Inheritance of very low serum dopamine-beta-hydroxylase activity.  

PubMed Central

Serum dopamine-beta-hydroxylas (DBH) activity was measured in blood samples obtained from 841 children ages 6-12, 277 adults subjects, and 114 relatives of children with serum DBH activity of less than 50 units. Approximately 4% of the children and 3% of the adult subjects tested had very low sweum DBH activity (50 units or less). Because these subjects appeared to make up a separate subgroup within the population and because of a striking familial aggregation of subjects with very low enzyme activity, serum DBH activity was measured in blood obtained from members of 22 families of probands with very low serum enzyme activity. The results of sibship and pedigree analyses of the data were compatible with autosomal recessive inheritance of very low serum DBH activity. Unaffected parents of probands had serum DBH activity intermediate between that found in affected individuals and in control population. No significant correlation of serum DBH activity with either systolic or diastolic blood pressure was found in this randomly selected population of children. PMID:1163533

Weinshilboum, R M; Schorott, H G; Raymond, F A; Weidman, W H; Elveback, L R

1975-01-01

408

Association of serum cotinine levels and hypertension in never smokers.  

PubMed

Hypertension is a major public health problem. Identifying novel risk factors for hypertension, including widely prevalent environmental exposures, is therefore important. Active smoking is a well-known risk factor for hypertension and cardiovascular diseases. However, there are no studies investigating the relationship between secondhand smoke exposure, measured objectively by serum cotinine, and high blood pressure among never smokers. We examined 2889 never smokers from the National Health and Nutrition Examination Survey 2005-2008. Our exposure of interest was secondhand smoke exposure among never smokers, estimated by serum cotinine level, and our main outcome was hypertension (n=1004). We found that in never smokers, higher serum cotinine levels were positively associated with hypertension. In comparison with those with serum cotinine levels ? 0.025 ng/mL, the multivariable odds ratio (95% confidence interval) of hypertension among those with serum cotinine levels ? 0.218 ng/mL was 1.44 (1.01-2.04). In addition, higher serum cotinine was positively associated with mean change in systolic blood pressure (odds ratio [95% confidence interval], 3.24 [0.86-5.63]; P=0.0061). However, no association was present with diastolic blood pressure. In conclusion, in never smokers, higher secondhand smoke exposure measured objectively by serum cotinine levels was found to be associated with systolic blood pressure and hypertension independent of age, sex, ethnicity, education, alcohol drinking, body mass index, glycohemoglobin, total cholesterol, and other confounders. PMID:23184382

Alshaarawy, Omayma; Xiao, Jie; Shankar, Anoop

2013-02-01

409

Serum oestradiol levels in male partners of infertile couples.  

PubMed

A prospective clinical study was performed in the reproduction centre of Ichikawa General Hospital (Chiba, Japan) to investigate the relationship between sperm quality and serum oestradiol (E2) level in male partners of infertile couples. The semen parameters and blood samples were assessed in relation to several variables, including body mass index (BMI) and serum oestradiol (E2) levels. Four hundred and nine male partners of infertile couples aged 22-55 years (mean: 36.5 years) were referred to the reproduction centre. In total, 143 patients (35.0%) were included in the low E2 level group (18 pg ml(-1)  ? E2). Serum E2 levels were slightly correlated with testosterone levels, BMI and serum FSH levels. Total motile sperm count and morphology were decreased in low E2 level group. In multivariate analysis, serum testosterone, E2 levels, existence of varicocele and age were risk factors for decreased semen quality. Serum E2 might be associated with BMI, serum testosterone level and spermatogenesis. PMID:25059733

Hagiuda, J; Ishikawa, H; Marumo, K

2014-07-25

410

EFFECT OF THE ANTIBACTERIAL SERUM FACTOR ON STAPHYLOCOCCAL INFECTIONS  

PubMed Central

Yotis, W. W. (Loyola University Medical School, Chicago, Ill.). Effect of the antibacterial serum factor on staphylococcal infections. J. Bacteriol. 83:137–143. 1962—Intracerebral injections of mice with 1 to 5 × 106 washed viable cells previously exposed for 1 hr at 4 C to 2 mg/ml of the serum factor resulted in 0 to 30% mortality when three recent isolates of yellow, hemolytic, coagulase-positive strains of Staphylococcus aureus were used. Mice inoculated in the same manner with the above strains, but exposed to an inactive preparation of the serum factor, showed a 60 to 90% mortality. Addition of partially purified coagulase to the serum factor neutralized the protective action of the serum factor. The serum factor was found primarily in the supernatant obtained following 62% (NH4)2SO4 saturation of the water-soluble globulin portion and precipitated by one-half volume of undiluted 95% ethanol. Plate counts, manometric techniques, and animal protection studies were employed to follow purification of the serum factor. If dry weight is taken as the criterion of purification, the active substance showed a 40-fold purification over a previous preparation of this substance. PMID:14009315

Yotis, William W.

1962-01-01

411

Serum concentrations of polychlorinated dibenzo-p-dioxins among ceramicists.  

PubMed

Polychlorinated dibenzo-p-dioxins (PCDDs) occur naturally in ball clay at elevated concentrations. Thus, persons who habitually work with clay may be at risk for exposure to PCDDs. An earlier case report provided some evidence of elevated PCDD levels in serum for long-term hobby ceramicists; however, no previous study has measured serum dioxin concentrations among ceramicists. This study measured PCDD serum levels for 27 individuals involved in ceramics making. The average residual, defined as the average of the [log measured serum lipid concentration – log background serum lipid concentration], was calculated and then tested to determine whether it was significantly different from zero. The p-values for the average residuals indicated that the serum lipid concentrations for several PCDD congeners were elevated relative to background. The number of significant residuals increased dramatically if the background concentrations were adjusted to account for the fact that they were not contemporaneous with the measurements for the ceramicists. The ratio of the 1,2,3,6,7,8-HxCDD concentration to the 1,2,3,7,8,9-HxCDD concentration was greater than 1.0, unlike in ball clay, suggesting that although long-term working with ball clay elevates the PCDD levels in serum somewhat, it is not the predominant source of the PCDD body burden for ceramicists. PMID:25463261

Demond, Avery; Jiang, Xiaohui; Broadwater, Kendra; Meeker, John; Luksemburg, William; Maier, Martha; Garabrant, David; Franzblau, Alfred

2015-01-01

412

Serum miRNA Signature in Moyamoya Disease  

PubMed Central

Moyamoya disease (MMD) is a cerebrovascular disease characterized by progressive stenosis of the intracranial internal carotid arteries and their proximal branches. However, the etiology of this rare disease remains unknown. Serum microRNA (miRNA) profiles have been screened to identify novel biomarkers of prognostic values. Here, we identified serum miRNAs that might play an important role in the pathogenesis of MMD. A genome-wide miRNA array analysis of two pooled serum samples from patients with MMD and controls revealed 94 differentially expressed serum miRNAs, including 50 upregulated and 44 downregulated miRNAs. In an independent MMD cohort, real-time PCR confirmed that miR-106b, miR-130a and miR-126 were significantly upregulated while miR-125a-3p was significantly downregulated in serum. GO analysis showed that the differentially expressed serum miRNAs were enriched in metabolic processes, transcription and signal transduction. Pathway analysis showed that the most enriched pathway was mTOR signaling pathway with 16 potential, functional targets. Finally, we found that 16 and 13 aberrant serum miRNAs coordinately inhibited RNF213 and BRCC3 protein expression at the posttranscriptional level, respectively, resulting in defective angiogenesis and MMD pathogenesis. To our knowledge, this is the first study to identify a serum miRNA signature in MMD. Modulation of the mechanism underlying the role of serum miRNAs in MMD is a potential therapeutic strategy and warrants further investigations. PMID:25093848

Huang, Qinghai; Yang, Pengfei; Hong, Bo; Xu, Yi; Zhao, Wenyuan; Liu, Jianmin; Li, Qiang

2014-01-01

413

Effects of serum and plasma matrices on multiplex immunoassays  

PubMed Central

Multiplexed fluorescence or electrochemiluminescence immunoassays of soluble cytokines are commonly performed in the context of human serum or plasma, to look for disease biomarkers and to monitor the immune system in a simple and minimally invasive way. These assays provide challenges due to the complexities of the matrix (serum or plasma) and the presence of many cytokines near the limit of detection of the assay. Here, we compare the readout of matched serum and plasma samples, which are generally correlated. However, a subset of cytokines usually have higher levels in serum, and the non-specific background is significantly increased in serum versus plasma. Presumably as a result of this non-specific background, disease-related decreases in low-abundance cytokines can sometimes be detected in plasma but not in serum. We further show, through spike recovery experiments, that both serum and plasma inhibit the readout of many cytokines, with some variability between donors, but with serum causing greater inhibition than plasma in many cases. Standard diluents from different vendors can partially reverse this inhibition to varying degrees. Dilution of samples can also partly overcome the inhibitory effect of the matrix. We also show that dilution is nonlinear and differentially affects various cytokines. Together, these data argue that (1) plasma is a more sensitive matrix for detecting changes in certain low-abundance cytokines; (2) calculation of concentrations in serum or plasma matrices is inherently inaccurate; and (3) dilution of samples should not be assumed to be linear, i.e., all comparisons need to be made among similarly diluted samples. PMID:24522699

Rosenberg-Hasson, Yael; Hansmann, Leo; Liedtke, Michaela; Herschmann, Iris

2015-01-01

414

Serum bicarbonate and mortality in adults in NHANES III  

PubMed Central

Background Low serum bicarbonate concentration is a risk factor for death in people with chronic kidney disease (CKD). Whether low serum bicarbonate is a mortality risk factor for people without CKD is unknown. Methods National Health and Nutrition Examination Survey III (NHANES III) adult participants were categorized into one of four serum bicarbonate categories: <22, 22–25, 26–30 and ?31 mM. Cox models were used to determine the hazards of death in each serum bicarbonate category, using 26–30 mM as the reference group, in the (i) entire population, (ii) non-CKD subgroup and (iii) CKD subgroup. Results After adjusting for age, gender, race, estimated glomerular filtration rate, albuminuria, diuretic use, smoking, C-reactive protein, cardiovascular disease, protein intake, diabetes, hypertension, body mass index, lung disease and serum albumin, the hazards of death in the <22 mM serum bicarbonate category were 1.75 (95% CI: 1.12–2.74), 1.56 (95% CI: 0.78–3.09) and 2.56 (95% CI: 1.49–4.38) in the entire population, non-CKD subgroup and CKD subgroup, respectively, compared with the reference group. Hazard ratios in the other serum bicarbonate categories in the entire population and non-CKD and CKD subgroups did not differ from the reference group. Conclusions Among the NHANES III participants, low serum bicarbonate was not observed to be a strong predictor of mortality in people without CKD. However, low serum bicarbonate was associated with a 2.6-fold increased hazard of death in people with CKD. PMID:23348878

Raphael, Kalani L.; Zhang, Yingying; Wei, Guo; Greene, Tom; Cheung, Alfred K.; Beddhu, Srinivasan

2013-01-01

415

Clinical significance of serum thymus and activation-regulated chemokine in gastric cancer: potential as a serum biomarker.  

PubMed

Thymus and activation-regulated chemokine (TARC) can stimulate cancer cell proliferation and migration. The present study evaluated the clinical significance of serum TARC in gastric cancer (GC). We measured serum TARC, macrophage-derived chemokine, monocyte chemotactic protein-1 and stem cell factor (SCF) levels using a chemiluminescent immunoassay along the GC carcinogenesis (normal, high-risk, early GC [EGC] and advanced GC [AGC]) in both training (N = 25 per group) and independent validation datasets (90 normal, 30 high-risk, 50 EGC and 50 AGC). Serum levels were compared among groups using one-way analysis of variance. To evaluate the diagnostic potential of serum TARC for GC, receiver operating characteristic curve and logistic regression analyses were performed. Correlations between serum TARC and GC clinicopathological features were analyzed using Spearman's correlation. In the training dataset, serum TARC correlated with serum MDC, MCP-1 and SCF. However, only serum TARC and SCF were significantly higher in cancer groups than non-cancer groups (P < 0.001). In the validation dataset, serum TARC also increased along the GC carcinogenesis; the AGC group (167.2 ± 111.1 ng/mL) had significantly higher levels than the EGC (109.1 ± 67.7 ng/mL), the high-risk (66.2 ± 47.7 ng/mL) and the normal (67.5 ± 36.2 ng/mL) groups (Bonferroni, all P < 0.001). Receiver operating characteristic curves and logistic regression demonstrated the remarkable diagnostic potential of serum TARC as a single marker (72.0% sensitivity and 71.1% specificity; cutoff point, 0.37; logistic regression) and in a multiple-marker panel (72.6% sensitivity and 88.2% specificity; cutoff point, 0.54). Spearman's correlation showed that serum TARC was closely correlated with tumor size (?s = 0.227, P = 0.028), T-stage (?s = 0.340, P = 0.001), N-stage (?s = 0.318, P = 0.002) and M-stage (?s = 0.346, P = 0.001). Serum TARC is a promising serum biomarker for GC. PMID:25154912

Lim, Jong-Baeck; Kim, Do-Kyun; Chung, Hye Won

2014-10-01

416

Microfluidic chemical reaction circuits  

DOEpatents

New microfluidic devices, useful for carrying out chemical reactions, are provided. The devices are adapted for on-chip solvent exchange, chemical processes requiring multiple chemical reactions, and rapid concentration of reagents.

Lee, Chung-cheng (Irvine, CA); Sui, Guodong (Los Angeles, CA); Elizarov, Arkadij (Valley Village, CA); Kolb, Hartmuth C. (Playa del Rey, CA); Huang, Jiang (San Jose, CA); Heath, James R. (South Pasadena, CA); Phelps, Michael E. (Los Angeles, CA); Quake, Stephen R. (Stanford, CA); Tseng, Hsian-rong (Los Angeles, CA); Wyatt, Paul (Tipperary, IE); Daridon, Antoine (Mont-Sur-Rolle, CH)

2012-06-26

417

Chemical and Biomolecular Engineering  

E-print Network

Chemical and Biomolecular Engineering Combining theory and neutron scattering to understand molecular diffusion in porous materials David Sholl School of Chemical & Biomolecular Engineering Georgia Institute of Technology #12;Chemical and Biomolecular Engineering Porous materials www

Pennycook, Steve

418

Supplements in human islet culture: human serum albumin is inferior to fetal bovine serum.  

PubMed

Culture of human islets before clinical transplantation or distribution for research purposes is standard practice. At the time the Edmonton protocol was introduced, clinical islet manufacturing did not include culture, and human serum albumin (HSA), instead of fetal bovine serum (FBS), was used during other steps of the process to avoid the introduction of xenogeneic material. When culture was subsequently introduced, HSA was also used for medium supplementation instead of FBS, which was typically used for research islet culture. The use of HSA as culture supplement was not evaluated before this implementation. We performed a retrospective analysis of 103 high-purity islet preparations (76 research preparations, all with FBS culture supplementation, and 27 clinical preparations, all with HSA supplementation) for oxygen consumption rate per DNA content (OCR/DNA; a measure of viability) and diabetes reversal rate in diabetic nude mice (a measure of potency). After 2-day culture, research preparations exhibited an average OCR/DNA 51% higher (p < 0.001) and an average diabetes reversal rate 54% higher (p < 0.05) than clinical preparations, despite 87% of the research islet preparations having been derived from research-grade pancreata that are considered of lower quality. In a prospective paired study on islets from eight research preparations, OCR/DNA was, on average, 27% higher with FBS supplementation than that with HSA supplementation (p < 0.05). We conclude that the quality of clinical islet preparations can be improved when culture is performed in media supplemented with serum instead of albumin. PMID:22863057

Avgoustiniatos, Efstathios S; Scott, William E; Suszynski, Thomas M; Schuurman, Henk-Jan; Nelson, Rebecca A; Rozak, Phillip R; Mueller, Kate R; Balamurugan, A N; Ansite, Jeffrey D; Fraga, Daniel W; Friberg, Andrew S; Wildey, Gina M; Tanaka, Tomohiro; Lyons, Connor A; Sutherland, David E R; Hering, Bernhard J; Papas, Klearchos K

2012-01-01

419

Tuning the serum persistence of human serum albumin domain III:diabody fusion proteins  

PubMed Central

The long circulation persistence of human serum albumin (HSA) is enabled by its domain III (DIII) interaction with the neonatal Fc receptor (FcRn). A protein scaffold based on HSA DIII was designed. To modify the serum half life of the scaffold, residues H535, H510, and H464 were individually mutated to alanine. HSA DIII wild type (WT) and variants were fused to the anti-carcinoembryonic antigen (CEA) T84.66 diabody (Db), radiolabeled with 124I and injected into xenografted athymic mice for serial PET/CT imaging. All proteins targeted the CEA-positive tumor. The mean residence times (MRT) of the proteins, calculated by quantifying blood activity from the PET images, were: Db-DIII WT (56.7 h), H535A (25 h), H510A (20 h), H464A (17 h), compared with Db (2.9 h). Biodistribution confirmed the order of blood clearance from slow to fast: Db-DIII WT > H535A > H510A > H464A > Db with 4.0, 2.0, 1.8, 1.6 and 0.08 %ID/g of remaining blood activity at 51 h, respectively. This study demonstrates that attenuating the DIII–FcRn interaction provides a way of controlling the pharmacokinetics of the entire Db-DIII fusion protein without compromising tumor targeting. H464 appears to be most crucial for FcRn binding (greatest reduction in MRT), followed by H510 and H535. By mutating the DIII scaffold, we can dial serum kinetics for imaging or therapy applications. PMID:20802234

Kenanova, Vania E.; Olafsen, Tove; Salazar, Felix B.; Williams, Lawrence E.; Knowles, Scott; Wu, Anna M.

2010-01-01

420

Serum antibody profiles of Sarcoptes scabiei infested or immunized rabbits.  

PubMed

The circulating antibody profiles of rabbits infected or immunized with Sarcoptes scabiei var. canis were compared. Crossed immuno-electrophoretic analysis showed that infested hosts produced serum antibody to 12 proteins (antigens) in an extract made from sarcoptic mite bodies. In contrast, rabbits immunized with an extract made from mite bodies produced antibody to 20 Sarcoptes proteins (antigens). SDS-PAGE/immunoblot analysis revealed that serum from immunized rabbits contained antibodies that bound strongly to proteins of 25 and 39-52 kD that were only barely visualized by antibodies in serum from infested rabbits. PMID:7883255

Morgan, M S; Arlian, L G

1994-01-01

421

Are serum bile salt concentrations raised in hyperlipidaemia?  

PubMed Central

We have studied serum fasting and postprandial primary bile salt concentrations in a group of 10 consecutive hyperlipidaemic subjects. The efficiency of hepatic bile salt clearance in the same subjects was aslo studied using an injected dose of sodium glycocholate. No increase in serum fasting or postprandial concentrations of the primary bile salts were observed and hepatic bile salt clearance was only marginally abnormal in one subject. The presence of hyperlipidaemia does not invalidate the use of serum conjugated bile salt analysis for the detection of liver diseases. PMID:7399323

Beckett, G J; Douglas, J G; Finlayson, N D; Percy-Robb, I W

1980-01-01

422

Determinations of morin, quercetin and their conjugate metabolites in serum.  

PubMed

Morin and quercetin are isomeric antioxidant flavonols. High-performance liquid chromatographic methods were developed for the quantitation of morin and quercetin in serum. The method employed a Cosmosil RP-18 column, using acetonitrile/0.2% o-phosphoric acid 28/72 and 27/73 (v/v) as mobile phases, with ethyl paraben and 6,7-dimethoxycoumarin used as internal standards for morin and quercetin, respectively. Moreover, a strategy to stabilize morin/quercetin released from their glucuronides/sulfates in serum during hydrolysis was established. The present methods are applicable for determining morin, quercetin, and their glucuronides/sulfates in serum. PMID:11510497

Hsiu, S L; Tsao, C W; Tsai, Y C; Ho, H J; Chao, P D

2001-08-01

423

Interaction of anticancer drugs with human and bovine serum albumin  

NASA Astrophysics Data System (ADS)

The properties of 5-fluorouracil (5FU), 6-azauracil (6AU), 6-mercaptopurine (6MP), thiouracil (2TU) and thioimidazole (TI), as a quencher of fluorescence of tryptophanyl Trp 214 residue in serum albumin were studied. For the molar ratio [ligand]: [BSA]=30: 1 the decrease of protein fluorescence due to the presence of thiouracil as a quencher attains 90%, while imidazole derivative-thiamazole quenches the BSA fluorescence only by 25%. To estimate the character of the binding between studied quencher and human and bovine serum albumin the Scatchard and Stern-Volmer methods were used. The binding stoichiometry of allopurinol-mercaptopurine-serum albumin complex was studied.

Su?kowska, A.; Równicka, J.; Bojko, B.; Su?kowski, W.

2003-06-01

424

Enhanced BDNF serum levels in patients with severe pathological gambling.  

PubMed

Although the pathophysiology of gambling is unknown, an involvement of midbrain dopaminergic pathway has been hypothesized. In this study, the association between brain-derived neurotrophic factor (BDNF) and pathological gambling was investigated. We measured BDNF serum levels in (1) video players (n=10); (2) card players (n=9); (3) mixed players (n=21; both video and card players) and (4) age-matched controls (n=18). Mixed players had increased BDNF serum levels as compared to controls and higher South Oaks Gambling Screen score as compared to card or video players. Thus, the data demonstrate that patients affected by severe pathological gambling show enhanced BDNF serum levels. PMID:22044515

Angelucci, Francesco; Martinotti, Giovanni; Gelfo, Francesca; Righino, Elisabetta; Conte, Gianluigi; Caltagirone, Carlo; Bria, Pietro; Ricci, Valerio

2013-07-01

425

Atomic structure and chemistry of human serum albumin  

NASA Technical Reports Server (NTRS)

The three-dimensional structure of human serum albumin has been determined crystallographically to a resolution of 2.8 A. It comprises three homologous domains that assemble to form a heart-shaped molecule. Each domain is a product of two subdomains that possess common structural motifs. The principal regions of ligand binding to human serum albumin are located in hydrophobic cavities in subdomains IIA and ILIA, which exhibit similar chemistry. The structure explains numerous physical phenomena and should provide insight into future pharmacokinetic and genetically engineered therapeutic applications of serum albumin.

He, Xiao M.; Carter, Daniel C.

1992-01-01

426