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1

Perfluoroalkyl chemicals and elevated serum uric acid in US adults  

PubMed Central

Background: Perfluoroalkyl chemicals, including perfluorooctanoic acid and perfluorooctane sulfonate, are man-made chemicals that have been detected in the blood of over 98% of the US population. Serum uric acid is a novel biomarker, even mild elevations of which has been implicated in the development of hypertension, diabetes mellitus, cardiovascular disease, and chronic kidney disease. We examined the relationship of serum perfluoroalkyl chemicals, including perfluorooctanoic acid and perfluorooctane sulfonate, and elevated uric acid levels in a representative sample of US adults. Methods: We examined 3883 participants from the 1999–2000 and 2003–2006 National Health and Nutritional Examination Surveys, a representative, multiethnic population-based survey of noninstitutionalized US adults. Serum perfluorooctanoic acid and perfluorooctane sulfonate were analyzed as quartiles. The main outcome was hyperuricemia. Results: We found that serum levels of perfluoroalkyl chemicals, including perfluorooctanoic acid and perfluorooctane sulfonate, were positively associated with hyperuricemia. This association appeared to be independent of confounders such as age, gender, race-ethnicity, body mass index, diabetes, hypertension, and serum cholesterol. Compared with subjects in quartile 1 (referent), the multivariate odds ratio for hyperuricemia among subjects in quartile 4 was 1.97 (95% confidence interval 1.44–2.70, P < 0.0001) for perfluorooctanoic acid and 1.48% (95% confidence interval 0.99–2.22, P = 0.0433) for perfluorooctane sulfonate. This observed association persisted in subgroup analysis by gender and body mass index. Conclusion: Our results demonstrate that elevated levels of perfluoroalkyl chemicals are associated with hyperuricemia even at low perfluoroalkyl chemical exposure levels as seen in the US general population.

Shankar, Anoop; Xiao, Jie; Ducatman, Alan

2011-01-01

2

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

Federal Register 2010, 2011, 2012, 2013

...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

3

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

Federal Register 2010, 2011, 2012, 2013

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

2012-08-15

4

Positive Association Between Perfluoroalkyl Chemicals and Hyperuricemia in Children  

PubMed Central

Hyperuricemia in children is associated with increased risk of high blood pressure, metabolic syndrome, and future cardiovascular disease. Serum perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) levels have been shown to be positively associated with hyperuricemia in adults, but the association in children remains unexplored. We therefore examined the association between serum PFOA and PFOS levels and hyperuricemia in a representative sample of US children. A cross-sectional study was performed on 1,772 participants ?18 years of age from the National Health and Nutrition Examination Survey 1999–2000 and 2003–2008. The main outcome of interest was hyperuricemia, defined as serum uric acid levels ?6 mg/dL. We found that serum levels of PFOA and PFOS were positively associated with hyperuricemia, independent of age, sex, race/ethnicity, body mass index, annual household income, physical activity, serum total cholesterol, and serum cotinine levels. Compared with subjects in quartile 1 (referent), subjects in quartile 4 had multivariable-adjusted odds ratios for hyperuricemia of 1.62 (95% confidence interval: 1.10, 2.37) for PFOA and 1.65 (95% confidence interval: 1.10, 2.49) for PFOS. Our findings indicate that serum perfluoroalkyl chemical levels are significantly associated with hyperuricemia in children even at the lower “background” exposure levels of the US general population.

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

2013-01-01

5

Perfluoroalkyl Chemicals and Chronic Kidney Disease in US Adults  

PubMed Central

Chronic kidney disease (CKD) is a major public health problem. Identifying novel risk factors for CKD, including widely prevalent environmental exposures, is therefore important. Perfluoroalkyl chemicals (PFCs), including perfluorooctanoic acid and perfluorooctane sulfonate, are manmade chemicals that have been detected in the blood of more than 98% of the US population. Results from experimental animal studies have suggested that an association between PFCs and CKD is plausible. However, in humans, the relation between serum PFCs and CKD has not been examined. The authors examined the relation of serum PFCs and CKD in 4,587 adult participants (51.1% women) from the combined 1999–2000 and 2003–2008 cycles of the National Health and Nutritional Examination Survey for whom PFC measurements were available. The main outcome was CKD, defined as a glomerular filtration rate of less than 60 mL/minute/1.73 m2. The authors found that serum levels of PFCs, including perfluorooctanoic acid and perfluorooctane sulfonate, were positively associated with CKD. This association was independent of confounders such as age, sex, race/ethnicity, body mass index, diabetes, hypertension, and serum cholesterol level. Compared with subjects in quartile 1 (referent), the multivariable odds ratio for CKD among subjects in quartile 4 was 1.73 (95% confidence interval: 1.04, 2.88; P for trend = 0.015) for perfluorooctanoic acid and 1.82 (95% confidence interval: 1.01, 3.27; P for trend = 0.019) for perfluorooctane sulfonate. The present results suggest that elevated PFC levels are associated with CKD.

Shankar, Anoop; Xiao, Jie; Ducatman, Alan

2011-01-01

6

Perfluoroalkyl acids in blood serum samples from children in Taiwan.  

PubMed

Severe perfluoroalkyl acid (PFAA) contamination resulting from the fast-growing semiconductor, electrochemical, and optoelectronic industries has been determined in the river water in the vicinity of the Taipei area, Taiwan, during recent years. However, little is known about body burdens of the PFAA contaminations in local residents, especially children living in the Taipei area recently. In this study, ten target PFAA analytes consisted of three perfluorosulfonates (PFSAs) and seven perfluorocarboxylates (PFCAs) in the blood serum samples, collected from 225 healthy children with an average age of 13.6 years in the Taipei area from 2009 to 2010, were analyzed via high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). As the dominant PFAA contaminant in the blood serum samples from Taiwanese children, perfluorooctane sulfonate (PFOS) contributed 86 % of all the target PFAA analytes, while the other nine analytes contributed less than 5 % individually. PFOS showed the highest median up to 29 ng/mL, ranging from 0.03 to 148 ng/mL, which was higher than that observed in the serum samples collected from Taiwanese children between 2006 and 2008. Statistically, serum concentrations of perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), and perfluorooctanoic acid (PFOA) had significantly positive correlations with ages of children (p?serum PFBS, PFHxS, and PFOA concentrations in the male children were considerably higher than those in the female children (p?=?0.049, p?=?0.000, p?=?0.000). PMID:24622984

Bao, Jia; Lee, Yungling Leo; Chen, Pau-Chung; Jin, Yi-He; Dong, Guang-Hui

2014-06-01

7

Associations between serum concentrations of perfluoroalkyl acids and serum lipid levels in a Chinese population.  

PubMed

Perfluoroalkyl acids (PFAAs) have been used in a variety of products for many years and have been detected worldwide in human serum. Previous studies have suggested the potential effects of PFAAs on serum lipids. To investigate the associations between serum concentrations of PFAAs and serum lipid levels, 133 participants were randomly selected from the people coming for health check-up in Yuanyang Red Cross Hospital of Henan, China. Linear regression analysis revealed that perfluoro-octanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA), with a median concentration of 1.43, 0.37, and 0.19ng/mL, respectively, were positively associated with total cholesterol (TC). Those in the highest quartile of PFOA exposure had ln-TC levels 0.24mmol/L higher than those in the lowest quartile. For PFNA and PFDA, effect estimates were 0.25 and 0.16mmol/L, respectively. A positive association between high-density lipoprotein cholesterol (HDLC) and PFDA was found, and there was a 0.18mmol/L increase of HDLC for the top PFDA quartile compared with the lowest quartile. PFOA and PFNA were positively associated with low-density lipoprotein cholesterol (LDLC). Ln-LDLC levels of people in both top PFOA and PFNA quartiles were 0.33mmol/L higher than those in the lowest quartiles. Logistic regression analysis indicated that increased PFOA and PFOS quartiles were positively associated with an increased risk of abnormal TC and LDLC when controlling for no confounding factors. PMID:24863755

Fu, Yaning; Wang, Tieyu; Fu, Quanliang; Wang, Pei; Lu, Yonglong

2014-08-01

8

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

SciTech Connect

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

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

2008-09-15

9

40 CFR 721.2675 - Perfluoroalkyl epoxide (generic name).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Perfluoroalkyl epoxide (generic name). 721.2675 Section...Substances § 721.2675 Perfluoroalkyl epoxide (generic name). (a) Chemical substances...identified generically as perfluoroalkyl epoxide (PMN P-86-562) is subject to...

2010-07-01

10

Profiles of perfluoroalkyl substances in the liver and serum of patients with liver cancer and cirrhosis in Australia.  

PubMed

The present cross-sectional study investigated 12 perfluoroalkyl substances (PFASs) in serum (n=79) and liver (n=66) samples from patients who had undergone liver transplantation for a range of conditions, such as hepatocellular carcinoma (HCC), cirrhosis due to chronic hepatitis C viral infection (HCV), both HCC and HCV, amyloidosis or acute liver failure. PFAS data from patients were compared to those in control serum (n=25) samples from liver donors with no known liver disease and to those in control liver (n=9) tissues collected during liver resection surgery. All samples showed detectable PFOS (serum: 0.621-126ng/mL; liver: 0.375-42.5ng/g wet wt) and PFOA (serum: 0.437-45.5ng/mL; liver: 0.101-2.25ng/g wet wt) concentrations. In general, in paired serum and liver samples, serum had higher PFOS, PFHxS, PFDA, PFNA, and PFOA concentrations than those in explanted livers from patients. These findings also suggest that pathological changes in diseased livers alter the distribution of PFASs between liver and serum. The results from control serum (2007-2008) suggested that PFOS, PFHxS, PFOA, and PFNA concentrations were lower than those previously reported from Australia for 2002-2003, and 2006-2007. The present study demonstrates, for the first time, the detection and comparison of a range of PFASs in the liver of patients with liver cancer and/or liver cirrhosis. PMID:23849467

Yeung, Leo W Y; Guruge, Keerthi S; Taniyasu, Sachi; Yamashita, Nobuyoshi; Angus, Peter W; Herath, Chandana B

2013-10-01

11

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.

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

2012-01-01

12

Association between Maternal Serum Perfluoroalkyl Substances during Pregnancy and Maternal and Cord Thyroid Hormones: Taiwan Maternal and Infant Cohort Study.  

PubMed

Background: Perfluoroalkyl substances (PFASs) are synthetic compounds that are widely used in industry and are often detectable in humans. In pregnant rats and their pups, PFASs can interfere with thyroid hormone homeostasis. In humans, maternal thyroid hormones supply the fetus throughout pregnancy, and thyroid hormones play a critical role in fetal growth and neurodevelopment.Objectives: We investigated the association between maternal PFAS exposure and thyroid hormone status in pregnant women and neonates.Methods: In a study of environmental exposure and health in Taiwan, we measured serum concentrations of nine PFASs and four thyroid hormones for 285 pregnant women in their third trimester, and also measured cord serum thyroid hormones for 116 neonates. Associations between maternal PFASs and maternal and cord thyroid hormones were examined in multiple linear regression models.Results: Perfluorohexanesulfonic acid concentrations were positively associated with maternal thyroid-stimulating hormone (TSH) levels. Pregnant women with higher levels of perfluorononanoic acid (PFNA), perfluoroundecanoic acid (PFUnDA), and perfluorododecanoic acid (PFDoDA) had lower free thyroxine (T4) and total T4 levels. For example, we estimated that maternal free T4 levels decreased 0.019 ng/dL (95% CI: -0.028, -0.009) with each nanogram per milliliter increase in maternal PFNA. Finally, maternal PFNA, PFUnDA, and PFDoDA levels were associated with lower cord total triiodothyronine (T3) and total T4 levels, and maternal perfluorodecanoic acid (PFDeA) was associated with lower cord total T3.Conclusions: Our results suggest that exposure to some PFASs during pregnancy may interfere with thyroid hormone homeostasis in pregnant women and fetuses.Citation: Wang Y, Rogan WJ, Chen PC, Lien GW, Chen HY, Tseng YC, Longnecker MP, Wang SL. 2014. Association between maternal serum perfluoroalkyl substances during pregnancy and maternal and cord thyroid hormones: Taiwan Maternal and Infant Cohort Study. Environ Health Perspect 122:529-534;?http://dx.doi.org/10.1289/ehp.1306925. PMID:24577800

Wang, Yan; Rogan, Walter J; Chen, Pau-Chung; Lien, Guang-Wen; Chen, Hsiao-Yen; Tseng, Ying-Chih; Longnecker, Matthew P; Wang, Shu-Li

2014-05-01

13

Association between Maternal Serum Perfluoroalkyl Substances during Pregnancy and Maternal and Cord Thyroid Hormones: Taiwan Maternal and Infant Cohort Study  

PubMed Central

Background: Perfluoroalkyl substances (PFASs) are synthetic compounds that are widely used in industry and are often detectable in humans. In pregnant rats and their pups, PFASs can interfere with thyroid hormone homeostasis. In humans, maternal thyroid hormones supply the fetus throughout pregnancy, and thyroid hormones play a critical role in fetal growth and neurodevelopment. Objectives: We investigated the association between maternal PFAS exposure and thyroid hormone status in pregnant women and neonates. Methods: In a study of environmental exposure and health in Taiwan, we measured serum concentrations of nine PFASs and four thyroid hormones for 285 pregnant women in their third trimester, and also measured cord serum thyroid hormones for 116 neonates. Associations between maternal PFASs and maternal and cord thyroid hormones were examined in multiple linear regression models. Results: Perfluorohexanesulfonic acid concentrations were positively associated with maternal thyroid-stimulating hormone (TSH) levels. Pregnant women with higher levels of perfluorononanoic acid (PFNA), perfluoroundecanoic acid (PFUnDA), and perfluorododecanoic acid (PFDoDA) had lower free thyroxine (T4) and total T4 levels. For example, we estimated that maternal free T4 levels decreased 0.019 ng/dL (95% CI: –0.028, –0.009) with each nanogram per milliliter increase in maternal PFNA. Finally, maternal PFNA, PFUnDA, and PFDoDA levels were associated with lower cord total triiodothyronine (T3) and total T4 levels, and maternal perfluorodecanoic acid (PFDeA) was associated with lower cord total T3. Conclusions: Our results suggest that exposure to some PFASs during pregnancy may interfere with thyroid hormone homeostasis in pregnant women and fetuses. Citation: Wang Y, Rogan WJ, Chen PC, Lien GW, Chen HY, Tseng YC, Longnecker MP, Wang SL. 2014. Association between maternal serum perfluoroalkyl substances during pregnancy and maternal and cord thyroid hormones: Taiwan Maternal and Infant Cohort Study. Environ Health Perspect 122:529–534;?http://dx.doi.org/10.1289/ehp.1306925

Rogan, Walter J.; Chen, Pau-Chung; Lien, Guang-Wen; Chen, Hsiao-Yen; Tseng, Ying-Chih; Longnecker, Matthew P.

2014-01-01

14

Polybrominated diphenyl ethers and perfluoroalkyl substances in serum of pregnant women: levels, correlations, and potential health implications.  

PubMed

Polybrominated diphenyl ethers (PBDEs), a group of flame retardants, and perfluoroalkyl substances (PFASs) were analysed in serum samples of pregnant women from Denmark to provide information about their exposure and to study indications of common exposure pathways. The main BDE congener was the fully brominated BDE-209 with a median value of 7.5 ng/g lipid (46 pg/mL; 9.8 pmol/g lipid). Other BDE congeners decreased in the order BDE-47 > BDE-99 > BDE-153. The summed concentration of tri- to hepta-BDEs was 7.7 ng/g lipid, i.e. in the higher end of previously reported concentrations from Europe, including plasma samples of pregnant Danish women. Total lipid contents were relatively low, on average 5.9 g/L (9.0 mmol/L). The main PFAS compound was perfluorooctane sulfonate with a median concentration of 8.4 ng/mL. Other PFASs decreased in the order perfluorooctanoic acid > perfluorononanoic acid > perfluorodecanoic acid > perfluorohexane sulfonate and resulted in a ?PFAS of 12 ng/mL. Within each group, compounds were highly intercorrelated with the exception of BDE-209, which was not correlated with any of the other compounds. No correlations were found either between PFASs and PBDEs suggesting different sources of exposure and/or pharmacokinetic and metabolisation processes. PBDE and PFAS concentrations were in the range associated with adverse effects in some epidemiological studies. PMID:24435476

Vorkamp, Katrin; Nielsen, Flemming; Kyhl, Henriette Boye; Husby, Steffen; Nielsen, Lars Bo; Barington, Torben; Andersson, Anna-Maria; Jensen, Tina Kold

2014-07-01

15

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

PubMed

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

Venkatesan, Arjun K; Halden, Rolf U

2014-07-01

16

Production of perfluoroalkylated nanospheres from buckminsterfullerene.  

PubMed

Perfluoroalkylated nanospheres have been prepared by reaction of fullerenes with a variety of fluoroalkyl radicals. The latter are generated by thermal or photochemical decomposition of fluoroalkyl iodides or fluorodiacyl peroxides. Up to 16 radicals add to C(60) to afford easily isolable fluoroalkylated derivatives. The monosubstituted radical adducts were detected by electron spin resonance in the early stages of the fluoroalkylation reactions. These spheroidal molecules are thermally quite stable, soluble in fluoroorganic solvents, chemically resistant to corrosive aqueous solutions, and more volatile than the parent fullerenes. Films of the sublimed material display properties typical for a perfluoroalkylated material. PMID:17789947

Fagan, P J; Krusic, P J; McEwen, C N; Lazar, J; Parkert, D H; Herron, N; Wasserman, E

1993-10-15

17

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...

18

A preliminary study of temporal differences in serum concentrations of perfluoroalkyl acids, among New York anglers, in the absence of known changes in manufacturing practices  

Microsoft Academic Search

Perfluorinated compounds have been manufactured in large quantities and used in myriad industrial processes and commercial applications. The aim of this preliminary study was to generate hypotheses with regard to differences in body burdens of perfluoroalkyl acids, among a sub-sample of participants from the New York State Angler Cohort Study, over a time interval during which no known substantial changes

M. S. Bloom; K. Kannan; H. M. Spliethoff; L. Tao; K. M. Aldous; J. E. Vena

2009-01-01

19

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 ...

20

Exposure to Perfluoroalkyl Acids and Markers of Kidney Function among Children and Adolescents Living near a Chemical Plant  

PubMed Central

Background: Serum levels of perfluorooctanoic acid (PFOA) have been associated with decreased renal function in cross-sectional analyses, but the direction of the association is unclear. Objectives: We examined the association of measured and model-predicted serum PFOA concentrations with estimated glomerular filtration rate (eGFR), a marker of kidney function, in a highly exposed population (median serum PFOA, 28.3 ng/mL). Methods: We measured serum creatinine, PFOA, perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonate (PFHxS) and calculated eGFR in 9,660 children 1 to < 18 years of age at study enrollment. We predicted concurrent and historical serum PFOA concentrations using a validated environmental, exposure, and pharmacokinetic model based on individual residential histories, and used linear regression to estimate the association between eGFR and measured and predicted serum PFOA concentrations. We hypothesized that predicted serum PFOA levels would be less susceptible to reverse causation than measured levels. Results: An interquartile range increase in measured serum PFOA concentrations [IQR ln(PFOA) = 1.63] was associated with a decrease in eGFR of 0.75 mL/min/1.73 m2 (95% CI: –1.41, –0.10; p = 0.02). Measured serum levels of PFOS, PFNA, and PFHxS were also cross-sectionally associated with decreased eGFR. In contrast, predicted serum PFOA concentrations at the time of enrollment were not associated with eGFR (–0.10; 95% CI: –0.80, 0.60; p = 0.78). Additionally, predicted serum PFOA levels at birth and during the first ten years of life were not related to eGFR. Conclusions: Our findings suggest that the cross-sectional association between eGFR and serum PFOA observed in this and prior studies may be a consequence of, rather than a cause of, decreased kidney function.

Josson, Jyoti; Elston, Beth; Bartell, Scott M.; Shin, Hyeong-Moo; Vieira, Veronica M.; Savitz, David A.; Fletcher, Tony; Wellenius, Gregory A.

2013-01-01

21

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

EPA Science Inventory

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

22

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

EPA Science Inventory

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

23

Toxicogenomic study of triazole fungicides and perfluoroalkyl acids in rat livers predicts toxicity and categorizes chemicals based on mechanisms of toxicity.  

PubMed

Toxicogenomic analysis of five environmental chemicals was performed to investigate the ability of genomics to predict toxicity, categorize chemicals, and elucidate mechanisms of toxicity. Three triazole antifungals (myclobutanil, propiconazole, and triadimefon) and two perfluorinated chemicals [perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS)] were administered daily via oral gavage for one, three, or five consecutive days to male Sprague-Dawley rats at single doses of 300, 300, 175, 20, or 10 mg/kg/day, respectively. Clinical chemistry, hematology, and histopathology were measured at all time points. Gene expression profiling of livers from three rats per treatment group at all time points was performed on the CodeLink Uniset Rat I Expression array. Data were analyzed in the context of a large reference toxicogenomic database containing gene expression profiles for over 630 chemicals. Genomic signatures predicting hepatomegaly and hepatic injury preceded those results for all five chemicals, and further analysis segregated chemicals into two distinct classes. The triazoles caused similar gene expression changes as other azole antifungals, particularly the induction of pregnane X receptor (PXR)-regulated xenobiotic metabolism and oxidative stress genes. In contrast, PFOA and PFOS exhibited peroxisome proliferator-activated receptor alpha agonist-like effects on genes associated with fatty acid homeostasis. PFOA and PFOS also resulted in downregulation of cholesterol biosynthesis genes, matching an in vivo decrease in serum cholesterol, and perturbation of thyroid hormone metabolism genes matched by serum thyroid hormone depletion in vivo. The concordance of in vivo observations and gene expression findings demonstrated the ability of genomics to accurately categorize chemicals, identify toxic mechanisms of action, and predict subsequent pathological responses. PMID:17383973

Martin, Matthew T; Brennan, Richard J; Hu, Wenyue; Ayanoglu, Eser; Lau, Christopher; Ren, Hongzu; Wood, Carmen R; Corton, J Christopher; Kavlock, Robert J; Dix, David J

2007-06-01

24

Associations between perfluoroalkyl compounds and immune and clinical chemistry parameters in highly exposed bottlenose dolphins (Tursiops truncatus).  

PubMed

Perfluoroalkyl compounds (PFCs) are ubiquitous, persistent chemical contaminants found in the environment, wildlife, and humans. Despite the widespread occurrence of PFCs, little is known about the impact these contaminants have on the health of wildlife populations. The authors investigated the relationship between PFCs (including ?perfluorocarboxylates, ?perfluoroalkyl sulfonates, perfluorooctane sulfonate, perfluorooctanoic acid, and perfluorodecanoic acid) and the clinocopathologic and immune parameters in a highly exposed population (n?=?79) of Atlantic bottlenose dolphins (mean ?PFCs?=?1970?ng/ml; range 574-8670?ng/ml) sampled from 2003 to 2005 near Charleston, South Carolina, USA. Age-adjusted linear regression models showed statistically significant positive associations between exposure to one or more of the PFC totals and/or individual analytes and the following immunological parameters: absolute numbers of CD2+ T cells, CD4+ helper T cells, CD19+ immature B cells, CD21+ mature B cells, CD2/CD21 ratio, MHCII+ cells, B cell proliferation, serum IgG1, granulocytic, and monocytic phagocytosis. Several PFC analyte groups were also positively associated with serum alanine aminotransferase, gamma-glutamyltransferase, creatinine, phosphorus, amylase, and anion gap and negatively associated with cholesterol levels, creatinine phosphokinase, eosinophils, and monocytes. Based on these relationships, the authors suggest that the PFC concentrations found in Charleston dolphins may have effects on immune, hematopoietic, kidney, and liver function. The results contribute to the emerging data on PFC health effects in this first study to describe associations between PFCs and health parameters in dolphins. PMID:23322558

Fair, Patricia A; Romano, Tracy; Schaefer, Adam M; Reif, John S; Bossart, Gregory D; Houde, Magali; Muir, Derek; Adams, Jeff; Rice, Charles; Hulsey, Thomas C; Peden-Adams, Margie

2013-04-01

25

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.

2010-01-01

26

Polyfluoroalkyl chemicals in the serum and milk of breastfeeding women  

Microsoft Academic Search

Polyfluoroalkyl chemicals (PFCs) comprise a group of man-made organic compounds, some of which are persistent contaminants with developmental toxicity shown in laboratory animals. There is a paucity of human perinatal exposure data. The US EPA conducted a pilot study (Methods Advancement for Milk Analysis) including 34 breastfeeding women in North Carolina. Milk and serum samples were collected at 2–7 weeks

Ondine S. von Ehrenstein; Suzanne E. Fenton; Kayoko Kato; Zsuzsanna Kuklenyik; Antonia M. Calafat; Erin P. Hines

2009-01-01

27

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

28

Toxicogenomic Study of Triazole Fungicides and Perfluoroalkyl Acids in Rat Livers Predicts Toxicity and Categorizes Chemicals Based on Mechanisms of Toxicity  

Microsoft Academic Search

Toxicogenomic analysis of five environmental chemicals was performed to investigate the ability of genomics to predict toxicity, categorize chemicals, and elucidate mechanisms of toxicity. Three triazole antifungals (myclobutanil, propiconazole, and triadime- fon) and two perfluorinated chemicals (perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS)) were administered daily via oral gavage for one, three, or five consecutive days to male Sprague-Dawley rats

Matthew T. Martin; Richard J. Brennan; Wenyue Hu; Eser Ayanoglu; Christopher Lau; Hongzu Ren; Carmen R. Wood; J. Christopher Corton; Robert J. Kavlock; David J. Dix

2007-01-01

29

Polyfluoroalkyl chemicals in the serum and milk of breastfeeding women.  

PubMed

Polyfluoroalkyl chemicals (PFCs) comprise a group of man-made organic compounds, some of which are persistent contaminants with developmental toxicity shown in laboratory animals. There is a paucity of human perinatal exposure data. The US EPA conducted a pilot study (Methods Advancement for Milk Analysis) including 34 breastfeeding women in North Carolina. Milk and serum samples were collected at 2-7 weeks and 3-4 months postpartum; 9 PFCs were assessed in milk and 7 in serum. Perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS) were found in nearly 100% of the serum samples. PFOS and PFOA were found at the highest concentrations. PFCs were below the limit of quantification in most milk samples. Serum concentrations of PFOS, PFOA and PFHxS were lower (p<0.01) at the second visit compared to the first visit. Living in North Carolina 10 years or longer was related to elevated PFOS, PFOA and PFNA (p

von Ehrenstein, Ondine S; Fenton, Suzanne E; Kato, Kayoko; Kuklenyik, Zsuzsanna; Calafat, Antonia M; Hines, Erin P

2009-06-01

30

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

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...721.7200 Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...generically as perfluoroalkyl aromatic carbamate modified alkyl methacrylate...

2010-07-01

31

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

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...721.7200 Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...generically as perfluoroalkyl aromatic carbamate modified alkyl methacrylate...

2013-07-01

32

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

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...721.7200 Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer...generically as perfluoroalkyl aromatic carbamate modified alkyl methacrylate...

2009-07-01

33

Communicating serum chemical concentrations to study participants: follow up survey  

PubMed Central

Background A considerable literature now supports the importance of effective communication with study participants, including how best to develop communication plans focusing on the uncertainty of health risks associated with particular environmental exposures. Strategies for communicating individual concentrations of environmental chemicals in human biological samples in the absence of clearly established safe or hazardous levels have been discussed from a conceptual basis and to a lesser extent from an empirical basis. We designed and evaluated an empirically based communication strategy for women of reproductive age who previously participated in a prospective study focusing on persistent environmental chemicals and reproductive outcomes. Methods A cohort of women followed from preconception through pregnancy or up to 12 menstrual cycles without pregnancy was given their individual serum concentrations for lead, dichloro-2,2-bisp-chlorophenyl ethylene, and select polychlorinated biphenyl congeners. Two versions of standardized letters were prepared depending upon women's exposure status, which was characterized as low or high. Letters included an introduction, individual concentrations, population reference values and guidance for minimizing future exposures. Participants were actively monitored for any questions or concerns following receipt of letters. Results Ninety-eight women were sent letters informing them of their individual concentrations to select study chemicals. None of the 89 (91%) participating women irrespective of exposure status contacted the research team with questions or concerns about communicated exposures despite an invitation to do so. Conclusions Our findings suggest that study participants can be informed about their individual serum concentrations without generating unnecessary concern.

2010-01-01

34

Cooking fish is not effective in reducing exposure to perfluoroalkyl and polyfluoroalkyl substances.  

PubMed

Consumption of fish is considered a part of a healthy diet; however, health risks from fish consumption exist due to potential exposure to various contaminants accumulated in fish. Cooking fish can reduce exposure to many organic chemicals in fish. Similar results have been presented for low levels of perfluoroalkyl and polyfluoroalkyl substances (PFASs), a class of contaminants of emerging concern, in grocery store fish. We examined the effectiveness of three cooking methods (i.e., baking, broiling, and frying) on reducing PFAS levels in four sport fish species. Samples of Chinook salmon, common carp, lake trout and walleye were collected from four rivers in Ontario, Canada and skin-off fillets were analyzed for regular groups of PFASs such as perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkane sulfonic acids (PFSAs), as well as perfluoroalkyl phosphonic acids (PFPAs), perfluoroalkyl phosphinic acids (PFPIAs) and polyfluoroalkyl phosphoric acid diesters (diPAPs), which are PFASs of emerging concern. Perfluorooctane sulfonate (PFOS) was the dominant PFAS detected and the concentrations were more than an order of magnitude higher than those reported for fish from grocery stores in Canada, Spain, and China. Although concentrations of PFOS in fish fillets generally increase after cooking, amounts of PFOS largely remain unchanged. Relatively minor differences in changes in the fish PFAS amounts after cooking depended on fish species and cooking method used. We conclude that cooking sport fish is generally not an effective approach to reduce dietary exposure to PFASs, especially PFOS. PMID:24561272

Bhavsar, Satyendra P; Zhang, Xianming; Guo, Rui; Braekevelt, Eric; Petro, Steve; Gandhi, Nilima; Reiner, Eric J; Lee, Holly; Bronson, Roni; Tittlemier, Sheryl A

2014-05-01

35

Chemical labelling of active serum thioester proteins for quantification  

PubMed Central

The complement serum proteins C3 and C4 and the protease inhibitor ?-2 macroglobulin are all members of the C3/?-2M thioester protein family, an evolutionarily ancient and conserved family that contains an intrachain thioester bond. The chemistry of the thioester bond is a key to the function of the thioester proteins. All these proteins function by covalently linking to their target by acyl transfer of the protein via the thioester moiety. We show that the signature thioester bond can be targeted with nucleophiles linked to a bioreporter molecule, site-specifically modifying the whole, intact thioester protein. Conditions were optimised to label selectively and efficiently pull-down unprocessed thioester-containing proteins from serum. We demonstrated pull-down of full-length C3, ?-2M and C4 from sera in high salt, using a biotinylated nucleophile and streptavidin-coated resin, confirmed by MALDI-TOF MS identification of the gel bands. The potential for the development of a quantitative method for measuring active C3 in serum was investigated in patient sera pre and post operation. Quantifying active C3 in clinical assays using current methods is difficult. Methods based on antibody detection (e.g. nephelometry) do not distinguish between active C3 and inactive breakdown products. C3-specific haemolytic assays can be used, but these require use of relatively unstable reagents. The current work represents a promising robust, enzyme- and antibody-free chemical method for detecting active thioester proteins in blood, plasma or serum.

Holm, Lotta; Ackland, Gareth L.; Edwards, Mark R.; Breckenridge, Ross A.; Sim, Robert B.; Offer, John

2012-01-01

36

Persistence of perfluoroalkylated substances in closed bottle tests with municipal sewage sludge  

Microsoft Academic Search

Background, aim, and scope  Perfluoroalkylated substances (PFAS) are chemicals with completely fluorinated alkyl chains. The specific properties of the\\u000a F–C bond give PFAS a high stability and make them very useful in a wide range of applications. PFAS also pose a potential\\u000a risk to the environment and humans because they have been recently characterized as persistent, bioaccumulative, and toxic.\\u000a The objective

Monica Sáez; Pim de Voogt; John R. Parsons

2008-01-01

37

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

Microsoft Academic Search

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

S. Mori; W. Morales

1989-01-01

38

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

Long, Manhai; Bossi, Rossana; Bonefeld-J?rgensen, Eva C.

2012-01-01

39

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

40

Physical and chemical characterization of horse serum carboxylesterase  

SciTech Connect

The serine carboxylesterase from horse serum was characterized by amino acid composition, peptide mapping, molecular and subunit weights, C- and N-terminal amino acid sequencing, and partial sequencing of the amino acids around the essential serine residue at the active site. A protocol was developed for using reversed-phase high pressure liquid chromatography to obtain homogeneous preparation of horse serum carboxylesterase. In addition, a number of kinetic properties were determined, including the substrate specificity, effect of pH, and activation energies. The horse serum carboxylesterase was characterized by unusually low turnover numbers with substrates commonly used with serine carboxylesterases. A variety of criteria were used to confirm the low turnover numbers and the concomitant high concentration of the esterase in the serum. These included reversed-phase high pressure liquid chromatography, disc-gel electrophoresis, and labelling with (/sup 14/C) diisopropylphosphofluoridate.

Torres, J.L.

1987-01-01

41

Physical and Chemical Characterization of the Serum Lipoproteins of Marine Mammals.  

National Technical Information Service (NTIS)

Characterized are some of the chemical and physical properties of the ultracentrifugal serum lipoprotein distributions of cetaceans (dolphins, porpoises, and whales) and pinnipeds (seals, sea lions, walruses). The complete ultracentrifugal distributions o...

D. L. Puppione

1969-01-01

42

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...

43

THE DEVELOPMENTAL TOXICITY OF PERFLUOROALKYL ACIDS AND THEIR DERIVATIVES  

EPA Science Inventory

Abstract Perfluoroalkyl acids such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have applications in numerous industrial and consumer products. Although the toxicology of some of these compounds has been investigated in the past, the widespread pr...

44

Metal-free photochemical aromatic perfluoroalkylation of ?-cyano arylacetates.  

PubMed

We report here an operationally simple protocol for the direct aromatic perfluoroalkylation and trifluoromethylation of ?-cyano arylacetates. This metal-free approach, which occurs at ambient temperature and under visible-light irradiation, is driven by the photochemical activity of electron donor-acceptor (EDA) complexes, formed in?situ by the interaction of transiently generated enolates and perfluoroalkyl iodides. Preliminary mechanistic studies are reported. PMID:24668827

Nappi, Manuel; Bergonzini, Giulia; Melchiorre, Paolo

2014-05-01

45

Iron-catalyzed 1,2-addition of perfluoroalkyl iodides to alkynes and alkenes.  

PubMed

Iron catalysis has been developed for the intermolecular 1,2-addition of perfluoroalkyl iodides to alkynes and alkenes. The catalysis has a wide substrate scope and high functional-group tolerance. A variety of perfluoroalkyl iodides including CF3 I can be employed. The resulting perfluoroalkylated alkyl and alkenyl iodides can be further functionalized by cross-coupling reactions. This methodology provides a straightforward and streamlined access to perfluoroalkylated organic molecules. PMID:24683156

Xu, Tao; Cheung, Chi Wai; Hu, Xile

2014-05-01

46

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

SciTech Connect

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

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

1987-03-01

47

Neonatal-maternal factors and perfluoroalkyl substances in cord blood.  

PubMed

Perfluoroalkyl substances (PFASs) can cross the placenta, enter fetal circulation, and were found to correlate with adverse fetal growth. However, determinants of cord blood PFASs are not fully characterized. The study aimed to explore the association between PFASs and neonatal-maternal factors within a Taiwanese birth cohort. We selected subjects from Taiwan Birth Panel Study, which enrolled 486 infant-mother pairs in 2004-2005. We collected cord blood and analyzed perfluorooctanoic acid (PFOA), perfluorooctanyl sulfonate (PFOS), perfluorononanoic acid (PFNA) and perfluoroundecanoic acid (PFUA) using a simple protein precipitation and an ultra-high performance liquid chromatography/tandem mass spectrometry. We retrieved information pertaining to maternal socio-demographics, lifestyle- and dietary-related factors through structured questionnaires during the postpartum hospital stay. A total of 439 subjects, with 90% response rate, have completed serum analysis and questionnaire survey. The median concentrations for PFOA, PFOS, PFNA, and PFUA in cord blood were 1.86, 5.67, 3.00, and 13.5ngmL(-1), respectively. After adjusting for potential confounders, multiple linear regression models revealed that log10-PFOA was positively associated with maternal age (?=0.011) and negatively associated with multiparity (?=-0.044). Log10-PFOS was negatively correlated with birth weight (?=-0.011) and higher maternal education (senior high school: ?=-0.067; university: ?=-0.088). Log10-PFUA tended to negatively associate with gender, male infants (?=-0.075), and using cosmetics during pregnancy (?=-0.065). Interestingly, presence of cockroaches in the home was positively associated with log10-PFOA (?=0.041) and 1og10-PFNA (?=0.123). In conclusion, this study demonstrated several factors to correlate with cord blood PFASs and further investigation are still needed for confirmation of exposure routes. PMID:23689097

Lien, Guang-Wen; Huang, Ching-Chun; Wu, Kuen-Yuh; Chen, Mei-Huei; Lin, Chien-Yu; Chen, Chia-Yang; Hsieh, Wu-Shiun; Chen, Pau-Chung

2013-08-01

48

Effect of pregnancy on the levels of selected perfluoroalkyl compounds for females aged 17-39 years: data from National Health and Nutrition Examination Survey 2003-2008.  

PubMed

The presence of perfluoroalkyl chemicals (PFC) in maternal serum may pose a risk to the developing fetus. A large-scale study to evaluate the extent of exposure to PFC in pregnant and nonpregnant females in the United States has not been conducted. The impact of pregnancy on the concentration levels of perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluorooctanoate (PFOA), and perfluorooctane sulfonate (PFOS) was assessed by analyzing data (n?=?1079) from National Health and Nutrition Examination Survey (NHANES) for the years 2003-2008 for females aged 17-39 yr. While pregnant females possessed lower serum concentrations of all 4 PFC than nonpregnant females, only the differences for PFOS were significant (9.6 vs. 11.8 ng/ml). Those mothers who breast-fed at least one child displayed significantly lower levels of PFOA (2.6 vs. 3.1 ng/ml) than those with non-breast-fed infants. The concentration levels of PFNA and PFOA decreased with increase in number of live births. While levels of PFHxS and PFOS markedly fell over the period 2003-2008, the levels of PFNA rose over the same time period. There was nonlinear elevation in levels of PFHxS and PFOS with age. Smoking was associated with increased levels of PFNA and PFOA. There was a significant, positive association between total cholesterol and PFOS as well as for serum albumin with PFHxS and PFOS. Elevated levels of PFNA and PFOA were associated with a rise in serum protein. Further studies are needed to adequately explain why smoking was associated with increased levels of PFNA and PFOA. PMID:23611181

Jain, Ram B

2013-01-01

49

Effect of serum starvation and chemical inhibitors on cell cycle synchronization of canine dermal fibroblasts  

Microsoft Academic Search

The cell cycle stage of donor cells and the method of cell cycle synchronization are important factors influencing the success of somatic cell nuclear transfer. In this study, we examined the effects of serum starvation, culture to confluence, and treatment with chemical inhibitors (roscovitine, aphidicolin, and colchicine) on cell cycle characteristics of canine dermal fibroblast cells. The effect of the

R. Khammanit; S. Chantakru; Y. Kitiyanant; J. Saikhun

2008-01-01

50

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.

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

2012-01-01

51

Parameters affecting the formation of perfluoroalkyl acids during wastewater treatment.  

PubMed

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

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

2014-05-15

52

Promotion of hepatocarcinogenesis by perfluoroalkyl acids in rainbow trout.  

PubMed

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 B(1) (AFB(1))- 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 AFB(1)-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

53

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...

54

Perfluoroalkyl acids in Lake Superior water: Trends and sources  

Microsoft Academic Search

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

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

2010-01-01

55

Perfluoroalkyl compounds in Danish wastewater treatment plants and aquatic environments  

Microsoft Academic Search

This study reports the results of a screening survey of perfluoroalkyl compounds (PFCs) in the Danish environment. The study included point sources (municipal and industrial wastewater treatment plants and landfill sites) and the marine and freshwater environments. Effluent and influent water and sewage sludge were analysed for point sources. Sediment, blue mussels (Mytilus edulis) and liver from plaice (Pleuronectes platessa),

R. Bossi; J. Strand; O. Sortkjær; M. M. Larsen

2008-01-01

56

The associations between serum perfluorinated chemicals and thyroid function in adolescents and young adults.  

PubMed

Perfluorinated chemicals (PFCs) have been widely used in a variety of products worldwide for years. However, the effect of PFCs on thyroid function has not yet been clearly defined. We recruited 567 subjects (aged 12-30 years) in a population-based cohort of adolescents and young adults with abnormal urinalysis in the childhood to determine the relationship between serum level of PFCs and the levels of serum free thyroxine (T4) and thyroid stimulating hormone (TSH). The geometric means and geometric standard deviation concentrations of perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA) and perfluoroundecanoic acid (PFUA) were 2.67 (2.96) ng/ml, 7.78 (2.42) ng/ml, 1.01 (3.48) ng/ml and 5.81 (2.92) ng/ml, respectively. Differences in the levels of free T4 and TSH across different categories of PFOA, PFOS and PFUA were insignificant. After controlling for confounding factors, multiple linear regression analyses revealed mean serum level of free T4 increased significantly across categories (<60th, 60-89 and >90th percentiles) of PFNA (P for trend =0.012 in the full model). The association between PFNA and free T4 was more significant in male subjects in age group 20-30, active smokers and in those with higher body mass index in stratified analysis. Serum concentrations of PFNA were associated with serum free T4 levels in adolescents and young adults. PMID:23177245

Lin, Chien-Yu; Wen, Li-Li; Lin, Lian-Yu; Wen, Ting-Wen; Lien, Guang-Wen; Hsu, Sandy H J; Chien, Kuo-Liong; Liao, Chien-Chang; Sung, Fung-Chang; Chen, Pau-Chung; Su, Ta-Chen

2013-01-15

57

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

58

Rapid trifluoromethylation and perfluoroalkylation of five-membered heterocycles by photoredox catalysis in continuous flow.  

PubMed

Trifluoromethylated and perfluoroalkylated heterocycles are important building blocks for the synthesis of numerous pharmaceutical products, agrochemicals and are widely applied in material sciences. To date, trifluoromethylated and perfluoroalkylated hetero-aromatic systems can be prepared utilizing visible light photoredox catalysis methodologies in batch. While several limitations are associated with these batch protocols, the application of microflow technology could greatly enhance and intensify these reactions. A simple and straightforward photocatalytic trifluoromethylation and perfluoroalkylation method has been developed in continuous microflow, using commercially available photocatalysts and microflow components. A selection of five-membered hetero-aromatics were successfully trifluoromethylated (12?examples) and perfluoroalkylated (5?examples) within several minutes (8-20?min). PMID:24706388

Straathof, Natan J W; Gemoets, Hannes P L; Wang, Xiao; Schouten, Jaap C; Hessel, Volker; Noël, Timothy

2014-06-01

59

Bioaccumulation of perfluoroalkyl compounds in midge (Chironomus riparius) larvae exposed to sediment.  

PubMed

Midge larvae (Chironomus riparius) were exposed to sediments from a deposition sampled at a site along the Rhône River (France) downstream of an industrial site releasing various perfluorinated chemicals. This sediment is characterized by high concentrations of perfluoroundecanoic acid (PFUnA) and perfluorotridecanoic acid (PFTrDA) and a low perfluorooctane sulfonate (PFOS) concentration. Concentrations of 23 perfluoroalkyl compounds, including C4-C14 carboxylate acids, C4-C10 sulfonates, and seven precursors, were analyzed in overlying and pore water, sediment, and larvae. Midge larvae accumulated carboxylate acids (C11-C14), PFOS, and two precursors (perfluorooctane sulfonamide: FOSA and 6:2 fluorotelomer sulfonic acid, 6:2 FTSA). These substances accumulated mainly during the fourth instar larvae exponential growth phase. Accumulation of 6:2 FTSA, PFUnA, and PFOS occured via trophic and tegumentary routes. Other compounds mainly accumulated from food. Kinetics followed a partition model, from which uptake and elimination constants were derived. PMID:24631894

Bertin, Delphine; Ferrari, Benoît J D; Labadie, Pierre; Sapin, Alexandre; Garric, Jeanne; Budzinski, Hélène; Houde, Magali; Babut, Marc

2014-06-01

60

Migration of perfluoroalkyl acids from food packaging to food simulants.  

PubMed

A broad range of fluorochemicals is used to impart oil and water barrier properties to paper and paperboard food packaging. Many of the fluorochemicals are applied to paper and paperboard as complex mixtures containing reaction products and by-products and unreacted starting materials. This work primarily focussed on the determination of seven perfluorocarboxylic acids (PFCAs) in two commercially available food contact papers: a di-perfluoro-alkyloxy-amino-acid and a perfluoroalkyl phosphate surfactant. In addition, the migration of the PFCAs into five food simulants from two commercial packages was evaluated. All seven PFCAs were detected in the range of 700-2220 µg kg?¹ of paper, while three perfluoroalkyl sulphonates were under the LOD. Results from migration tests showed that migration depends on paper characteristics, time and food simulant. The percentage of migration after 10 days at 40°C ranged from 4.8% to 100% for the two papers and different food simulants. PMID:23701306

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

2013-01-01

61

Perfluoroalkyl Acids in Marine Organisms from Lake Shihwa, Korea  

Microsoft Academic Search

To our knowledge, this is the first report of concentrations of perfluorooctanesulfonate (PFOS) and other perfluoroalkyl acids\\u000a (PFAs) in marine organisms from the industrialized region of Korea. Concentrations of eight PFAs were determined in three\\u000a species of fish (mullet, shad, and rockfish) and three species of marine invertebrates (blue crab, oyster, and mussel) from\\u000a Lake Shihwa, Korea. This is an

Hoon Yoo; Nobuyoshi Yamashita; Sachi Taniyasu; Kyu Tae Lee; Paul D. Jones; John L. Newsted; Jong Seong Khim; John P. Giesy

2009-01-01

62

Study on the binding interaction between perfluoroalkyl acids and DNA.  

PubMed

Perfluoroalkyl acids (PFAAs) are carcinogens, and elucidating their DNA binding properties is crucial for understanding PFAA genotoxicity. We have investigated the binding mode and affinity of five PFAAs to seven DNA molecules using fluorescence displacement and molecular docking analysis. DNA conformational changes upon PFAA binding were also examined by circular dichroism (CD). The data revealed that DNA intercalation was the dominant interaction mode of the PFAAs; however, these molecules also bound to grooves. The dissociation constants for the PFAAs ranged between 0.11 and 1,217.14 ?M, and between 3.46 and 2,141.21 ?M for DNA intercalation and groove binding, respectively. PFAAs that contain longer carbon chains had stronger DNA intercalation affinities. Binding to DNA was stronger for perfluoroalkyl sulfonates than for perfluorcarboxyl acids that contain the same number of carbons. This observation is postulated to arise from the presence of more fluorine and oxygen atoms in perfluoroalkyl sulfonates acting as hydrogen bond donors that facilitate stronger DNA intercalation. The binding of the PFAAs to DNA showed some CT-DNA sequence selectivity. Molecular docking analysis confirmed the DNA binding mode and affinities of the PFAAs. CD analysis revealed that the PFAAs weakened DNA base stacking and loosened DNA helicity. The present study has improved our understanding of the formation of PFAA-DNA adducts. PMID:23645002

Cao, Jie; Wei, Yin; Cheng, Yan

2013-12-01

63

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...

64

Role of tyrosine and tryptophan in chemically modified serum albumin on its tissue distribution.  

PubMed

To investigate the effect of functional groups in bovine serum albumin (BSA) on its tissue distribution characteristics, tyrosine (Tyr) or tryptophan (Trp) residues of BSA were chemically modified by tetranitromethane (TNM) and 2-hydroxy-5-nitrobenzyl bromide (HNB), respectively. BSA was successfully modified with each reagent depending on the amount of the reagent added to the reaction mixture, and TNM- and HNB-modified BSA derivatives with different degrees of modification were obtained. Circular dichroism measurements showed that slight secondary and large tertiary changes were detectable as the degree of modification increased. After intravenous injection into mice, all synthetic BSA derivatives were eliminated very slowly from the systemic circulation. However, (111)In-TNM(6.6)- and (111)In-HNB(2.0)-BSA, derivatives with a high degree of modification, showed a slightly faster disappearance from the systemic circulation and slightly higher accumulation in the liver than (111)In-unmodified BSA. Pharmacokinetic analyses also demonstrated that the modification of Tyr or Trp residues on BSA had only marginal effects on tissue distribution. These results indicate that the Tyr and Trp residues have little effect on the tissue distribution characteristics of serum albumins, and that the specific modification of these residues may be a promising approach to designing sustained drug delivery systems using serum albumins. PMID:16946511

Ma, Shen-Feng; Nishikawa, Makiya; Yabe, Yoshiyuki; Yamashita, Fumiyoshi; Hashida, Mitsuru

2006-09-01

65

Hydrophobicity of perfluoroalkyl isocyanate monolayers on oxidized aluminum surfaces.  

PubMed

Perfluoroalkyl isocyanate-derived monolayers were prepared on oxidized aluminum surfaces by chemical vapor deposition (CVD) of 1H,1H,2H,2H-perfluorodecyl isocyanate (CF(3)[CF(2)](7)CH(2)CH(2)N horizontal lineC horizontal lineO, i.e., R(F)-NCO). Two types of oxidized aluminum substrates were studied: electrochemically polished aluminum plates (Al(Al(2))(O(3))) and Al(Al(2))(O(3)) that was treated with boiling water ((BW)Al(Al(2))(O(3))). X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) confirmed that this CVD method produces a monolayer with a thickness of approximately 1.2 nm on Al(Al(2))(O(3)) through a carbamate linkage without discernible change in surface morphology. After monolayer deposition, hydrophilic Al(Al(2))(O(3)) surfaces become hydrophobic. Advancing and receding water contact angles are theta(A)/theta(R) = 125 degrees /103 degrees . AFM indicates that (BW)Al(Al(2))(O(3)) surfaces contain 10-15-nm-size pebble-like features. This is due to both chemical and physical erosion of the aluminum surface caused by the boiling water treatment. Due to the presence of these topographical features, the CVD of R(F)-NCO on (BW)Al(Al(2))(O(3)) induces superhydrophobicity (theta(A)/theta(R) = 167 degrees /165 degrees ). Al(Al(2))(O(3)) and (BW)Al(Al(2))(O(3)) based "control surfaces" were prepared with the conventional mono- and trifunctional organosilanes, 1H,1H,2H,2H-perfluorodecyldimethylchlorosilane (CF(3)[CF(2)](7)CH(2)CH(2)Si[CH(3)](2)Cl, R(F)-SiMe(2)Cl) and 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (CF(3)[CF(2)](7)CH(2)CH(2)Si[OCH(3)](3), R(F)-Si[OMe](3)) for comparison. In the case of R(F)-Si(OMe)(3), the theta(A)/theta(R) values for Al(Al(2))(O(3)) and (BW)Al(Al(2))(O(3)) are 125 degrees /110 degrees and 170 degrees /167 degrees , respectively. R(F)-SiMe(2)Cl-treated aluminum surfaces are much less hydrophobic. The theta(A)/theta(R) values for Al(Al(2))(O(3)) and (BW)Al(Al(2))(O(3)) are 107 degrees /69 degrees and 137 degrees /87 degrees , respectively. XPS analysis of surface coverage is consistent with the contact angle behavior and the water sensitivity. Stability of these three monolayers in water is in the order: R(F)-Si(OMe)(3) > R(F)-NCO > R(F)-SiMe(2)Cl. PMID:19432482

Hozumi, Atsushi; Kim, Bokyung; McCarthy, Thomas J

2009-06-16

66

Perfluoroalkyl acids in the Atlantic and Canadian Arctic Oceans.  

PubMed

We report here on the spatial distribution of C(4), C(6), and C(8) perfluoroalkyl sulfonates, C(6)-C(14) perfluoroalkyl carboxylates, and perfluorooctanesulfonamide in the Atlantic and Arctic Oceans, including previously unstudied coastal waters of North and South America, and the Canadian Arctic Archipelago. Perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) were typically the dominant perfluoroalkyl acids (PFAAs) in Atlantic water. In the midnorthwest Atlantic/Gulf Stream, sum PFAA concentrations (?PFAAs) were low (77-190 pg/L) but increased rapidly upon crossing into U.S. coastal water (up to 5800 pg/L near Rhode Island). ?PFAAs in the northeast Atlantic were highest north of the Canary Islands (280-980 pg/L) and decreased with latitude. In the South Atlantic, concentrations increased near Rio de la Plata (Argentina/Uruguay; 350-540 pg/L ?PFAAs), possibly attributable to insecticides containing N-ethyl perfluorooctanesulfonamide, or proximity to Montevideo and Buenos Aires. In all other southern hemisphere locations, ?PFAAs were <210 pg/L. PFOA/PFOS ratios were typically ?1 in the northern hemisphere, ?1 near the equator, and ?1 in the southern hemisphere. In the Canadian Arctic, ?PFAAs ranged from 40 to 250 pg/L, with perfluoroheptanoate, PFOA, and PFOS among the PFAAs detected at the highest concentrations. PFOA/PFOS ratios (typically ?1) decreased from Baffin Bay to the Amundsen Gulf, possibly attributable to increased atmospheric inputs. These data help validate global emissions models and contribute to understanding of long-range transport pathways and sources of PFAAs to remote regions. PMID:22548373

Benskin, Jonathan P; Muir, Derek C G; Scott, Brian F; Spencer, Christine; De Silva, Amila O; Kylin, Henrik; Martin, Jonathan W; Morris, Adam; Lohmann, Rainer; Tomy, Gregg; Rosenberg, Bruno; Taniyasu, Sachi; Yamashita, Nobuyoshi

2012-06-01

67

Serum amylase and isoamylase assay on the Hitachi 705 automatic clinical chemical analyzer.  

PubMed

The automated continuous alpha-amylase assay using p-nitrophenyl-alpha-D-maltoheptaoside (Boehringer Mannheim) as substrate on the Hitachi 705 clinical chemical analyzer, was compared with the Phadebas Kinetic Amylase Assay (Pharmacia Diagnostics) on the Hitachi 705. The two methods showed good correlation. The precision varied from 1.0 to 2.5% (CV) within-day and from 1.1 to 5.6% (CV) day-to-day. The substrate, p-nitrophenyl-alpha-D-maltoheptaoside, was also applied to an automated isoamylase assay. The amylase inhibitor from wheat was used to determine the ratio of pancreatic and salivary amylase activities of serum. About 80% of salivary type amylase was inhibited up to an activity level of 1000 U/l, while inhibition of pancreatic type amylase activity was only 10-15%. Ratios of pancreatic to salivary amylase from 0.1 to 10 can be evaluated in serum with wheat inhibitor. The precision of the isoamylase determination by the Boehringer amylase method was acceptable. PMID:6199455

Parviainen, M T; Koivula, T; Jokela, H

1984-01-01

68

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

PubMed

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

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

2014-06-17

69

Age- and gender-related accumulation of perfluoroalkyl substances in captive Chinese alligators (Alligator sinensis).  

PubMed

Fourteen perfluoroalkyl substances (PFASs) were measured in serum of the highly endangered captive Chinese alligators, whole body homogenates of six kinds of fish (alligator prey species), and pond water (alligator habitat) in the Anhui Research Center for Chinese Alligator Reproduction. Six PFASs, including PFOS and five perfluorinated carboxylates, were detected in all alligator samples. The most dominant PFAS was PFUnDA, with a mean value of 31.4 ng/mL. Significant positive correlations were observed among the six PFASs, suggesting that they shared similar sources of contamination. Significantly higher PFOS and PFUnDA levels were observed in males, but the other four PFCAs did not differ between genders. An age related PFAS bioaccumulation analysis showed a significant negative correlation of the concentrations for five PFCAs to age, which means that higher concentrations were found in younger animals. Bioaccumulation factors (BAF) in fish for PFASs ranged from 21 to 28,000, with lower BAF for PFOA than that for longer carbon chain PFCAs, including PFUnDA, PFDA, and PFNA. PMID:23660395

Wang, Jianshe; Zhang, Yating; Zhang, Fang; Yeung, Leo W Y; Taniyasu, Sachi; Yamazaki, Eriko; Wang, Renping; Lam, Paul K S; Yamashita, Nobuyoshi; Dai, Jiayin

2013-08-01

70

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

PubMed Central

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 PPAR? reporter model with a mixing ratio that is based on average serum levels in NHANES subjects. Availability of information regarding potential for additivity of PFAAs in mixtures is critically important for risk assessors who are concerned with the ability of the compounds to affect human health and impact ecological systems. It is clear that exposures are not to single compounds, but to mixtures of the PFAAs. This paper presents the results from the data collected using the design from Carr et al. along with subsequent analyses that were performed to classify the relationships among mixtures of PFAAs. A non-linear logistic additivity model was employed to predict relative luciferase units (RLU), an indicator of PPAR? activation. The results indicated a less than additive relationship among the four PFAAs. To determine if the possible “antagonism” is from the competition among or between carboxylates and sulfonates, four different binary mixtures were also studied. There was a less than additive relationship in all four binary mixtures. These findings are generally similar to two other reports of interfering interactions between PFAAs in mixtures. The most conservative interpretation for our data would be an assumption of additivity (and lack of a greater than additive interaction), with a potential for antagonistic interactions.

Carr, Caroline K.; Watkins, Andrew M.; Wolf, Cynthia J.; Abbott, Barbara D.; Lau, Christopher; Gennings, Chris

2013-01-01

71

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

PubMed

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 PPAR? reporter model with a mixing ratio that is based on average serum levels in NHANES subjects. Availability of information regarding potential for additivity of PFAAs in mixtures is critically important for risk assessors who are concerned with the ability of the compounds to affect human health and impact ecological systems. It is clear that exposures are not to single compounds, but to mixtures of the PFAAs. This paper presents the results from the data collected using the design from Carr et al. along with subsequent analyses that were performed to classify the relationships among mixtures of PFAAs. A non-linear logistic additivity model was employed to predict relative luciferase units (RLU), an indicator of PPAR? activation. The results indicated a less than additive relationship among the four PFAAs. To determine if the possible "antagonism" is from the competition among or between carboxylates and sulfonates, four different binary mixtures were also studied. There was a less than additive relationship in all four binary mixtures. These findings are generally similar to two other reports of interfering interactions between PFAAs in mixtures. The most conservative interpretation for our data would be an assumption of additivity (and lack of a greater than additive interaction), with a potential for antagonistic interactions. PMID:23470359

Carr, Caroline K; Watkins, Andrew M; Wolf, Cynthia J; Abbott, Barbara D; Lau, Christopher; Gennings, Chris

2013-04-01

72

Retinyl. beta. -glucoronide: its occurrence in human serum, chemical synthesis and biological activity  

SciTech Connect

When retinol is administered to rats, retinyl and retinoyl ..beta..-glucuronides appear in the bile. Retinyl or retinoyl ..beta..-glucuronide is also synthesized in vitro when rat liver microsomes are incubated with uridinediphosphoglucuronic acid and either retinol or retinoic acid. Retinoyl ..beta..-glucuronide, a major metabolite of retinoic acid in a number of tissues, is highly active biologically, has been chemically synthesized, and is found in human blood. The physiological significance of the glucuronides of vitamin A are not known yet. To investigate further its metabolism and possible physiological role, retinyl ..beta..-glucuronide was chemically synthesized from retinol and characterized by study of its ultra-violet spectrum (..gamma../sub max/ 325 nm in methanol, 329 nm in water), /sup 1/H-NMR and mass spectra. Retinyl ..beta..-glucuronide was extensively hydrolyzed by bacterial ..beta..-glucuronidase to retinol. Retinyl ..beta..-glucuronide is soluble in water and was detected in significant amounts in the serum of healthy human adults. The biological activity of synthetic retinyl ..beta..-glucuronide was determined in rats by the rat growth bioassay method.

Barua, A.B.; Batres, R.O.; Olson, J.A.

1986-01-01

73

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

74

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....

75

Major perfluoroalkyl acid (PFAA) concentrations and influence of food consumption among the general population of Daegu, Korea.  

PubMed

Perfluoroalkyl acids (PFAAs) have been used in various industrial and consumer products for decades, and have consequently been detected in human blood worldwide. In the present study, general adult population in Daegu, Korea (n=140, >20 years of old) was recruited, collected for serum, and analyzed for 13 major PFAAs. The influence of dietary and water consumption on serum PFAA levels was also evaluated. Perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane sulfonic acid (PFHxS) were frequently detected with relatively higher concentrations in blood serum. Most PFAA concentrations except for PFOA were detected in higher concentrations among males, and were positively correlated with age and body mass index (BMI). PFOA concentrations were relatively higher among the female of childbearing age, e.g., 20-49years old, raising concerns on potential impacts on fetus through transplacental transfer or lactation. In addition, the concentrations of PFOA in Daegu population were higher than other areas of Korea, suggesting a presence of distinctive sources in the area. Among food items, potato consumption was identified to be significant contributor to serum PFOA. For PFUnDA and PFTrDA levels, intake of fish/shellfish was positively associated. The results of this study will be useful in developing public health management options for PFAAs. PMID:22964400

Ji, Kyunghee; Kim, Sunmi; Kho, Younglim; Sakong, Joon; Paek, Domyung; Choi, Kyungho

2012-11-01

76

Perfluoroalkyl sulfonates and perfluorocarboxylates in two wastewater treatment facilities in Kentucky and Georgia  

Microsoft Academic Search

Discharge of effluents from municipal wastewater treatment plants (WWTPs) is a route for the introduction of certain organic contaminants into aquatic environments. Earlier studies have reported the occurrence of perfluorochemicals in effluents from WWTPs. In this study, contamination profiles of perfluorinated compounds (PFCs), including perfluoroalkyl sulfonates (PFASs; PFOS, PFOSA, PFHxS) and perfluoroalkyl carboxylates (PFACs; PFOA, PFNA, PFDA, PFDoDA, PFUnDA), were

Bommanna G. Loganathan; Kenneth S. Sajwan; Ewan Sinclair; Kurunthachalam Senthil Kumar; Kurunthachalam Kannan

2007-01-01

77

Indoor contamination with hexabromocyclododecanes, polybrominated diphenyl ethers, and perfluoroalkyl compounds: an important exposure pathway for people?  

PubMed

This review underlines the importance of indoor contamination as a pathway of human exposure to hexabromocyclododecanes (HBCDs), polybrominated diphenyl ethers (PBDEs), and perfluoroalkyl compounds (PFCs). There is ample evidence of substantial contamination of indoor dust with these chemicals and that their concentrations in indoor air exceed substantially those outdoors. Studies examining the relationship between body burden and exposure via indoor dust are inconsistent; while some indicate a link between body burdens and PBDE and HBCD exposure via dust ingestion, others find no correlation. Likewise, while concentrations in indoor dust and human tissues are both highly skewed, this does not necessarily imply causality. Evidence suggests exposure via dust ingestion is higher for toddlers than adults. Research priorities include identifying means of reducing indoor concentrations and indoor monitoring methods that provide the most "biologically-relevant" measures of exposure as well as monitoring a wider range of microenvironment categories. Other gaps include studies to improve understanding of the following: emission rates and mechanisms via which these contaminants migrate from products into indoor air and dust; relationships between indoor exposures and human body burdens; relevant physicochemical properties; the gastrointestinal uptake by humans of these chemicals from indoor dust; and human dust ingestion rates. PMID:20387882

Harrad, Stuart; de Wit, Cynthia A; Abdallah, Mohamed Abou-Elwafa; Bergh, Caroline; Björklund, Justina A; Covaci, Adrian; Darnerud, Per Ola; de Boer, Jacob; Diamond, Miriam; Huber, Sandra; Leonards, Pim; Mandalakis, Manolis; Ostman, Conny; Haug, Line Småstuen; Thomsen, Cathrine; Webster, Thomas F

2010-05-01

78

Culture of newborn monkey liver epithelial progenitor cells in chemical defined serum-free medium.  

PubMed

Studies with hepatic progenitor cells from non-human primates would allow better understanding of their human counterparts. In this study, rhesus monkey liver epithelial progenitor cells (mLEPCs) were derived from a small piece of newborn livers in chemical defined serum-free medium. Digested hepatic cells were treated in Ca(2+)-containing medium to form cell aggregates. Two types of cell aggregates were generated: elongated spindle cells and polygonal epithelial cells. Elongated spindle cells were expressed as vimentin and brachyury, and they were disappeared within 5 d in our cultures. The remaining type consisted of small polygonal epithelial cells that expressed cytokeratin 7 (CK7), CK8, CK18, nestin, CD49f, and E-cad, the markers of hepatic stem cells, but were negative for alpha-fetoprotein, albumin, and CK19. They can proliferate and be passaged, if on laminin or rat tail collagen gel, to initiate colonies. When cultured with dexamethasone and oncostatin M, the expression of mature hepatocyte markers, such as alpha-1-antitrypsin, intracytoplasmic glycogen storage, indocyanine green uptake, and lipid droplet generation, were induced in differentiated cells. If transferred onto mouse embryonic fibroblasts feeders, they gave rise to CK19-positive cholangiocytes with formation of doughnut-like structure. Thus, mLEPCs with bipotency were derived from newborn monkey liver and may serve as a preclinical model for assessment of cell therapy in humans. PMID:20568020

Ji, Shaohui; Jin, Lifang; Guo, Xiangyu; Ji, Weizhi

2010-09-01

79

Capturing Labile Sulfenamide and Sulfinamide Serum Albumin Adducts of Carcinogenic Arylamines by Chemical Oxidation  

PubMed Central

Aromatic amines and heterocyclic aromatic amines (HAAs) are a class of structurally related carcinogens that are formed during the combustion of tobacco or during the high temperature cooking of meats. These procarcinogens undergo metabolic activation by N-oxidation of the exocyclic amine group to produce N-hydroxylated metabolites, which are critical intermediates implicated in toxicity and DNA damage. The arylhydroxylamines and their oxidized arylnitroso derivatives can also react with cysteine (Cys) residues of glutathione or proteins to form, respectively, sulfenamide and sulfinamide adducts. However, sulfur-nitrogen linked adducted proteins are often difficult to detect because they are unstable and undergo hydrolysis during proteolytic digestion. Synthetic N-oxidized intermediates of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a carcinogenic HAA produced in cooked meats, and 4-aminobiphenyl, a carcinogenic aromatic amine present in tobacco smoke were reacted with human serum albumin (SA) and formed labile sulfenamide or sulfinamide adducts at the Cys34 residue. Oxidation of the carcinogen-modified SA with m-chloroperoxybenzoic acid (m-CPBA) produced the arylsulfonamide adducts, which were stable to heat and the chemical reduction conditions employed to denature SA. The sulfonamide adducts of PhIP and 4-ABP were identified, by liquid chromatography/mass spectrometry, in proteolytic digests of denatured SA. Thus, selective oxidation of arylamine-modified SA produces stable arylsulfonamide-SA adducts, which may serve as biomarkers of these tobacco and dietary carcinogens.

Peng, Lijuan; Turesky, Robert J.

2013-01-01

80

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

81

Association between Perfluoroalkyl substances and thyroid stimulating hormone among pregnant women: a cross-sectional study  

PubMed Central

Background Perfluoroalkyl substances (PFASs) are a group of highly persistent chemicals that are widespread contaminants in wildlife and humans. Exposure to PFAS affects thyroid homeostasis in experimental animals and possibly in humans. The objective of this study was to examine the association between plasma concentrations of PFASs and thyroid stimulating hormone (TSH) among pregnant women. Methods A total of 903 pregnant women who enrolled in the Norwegian Mother and Child Cohort Study from 2003 to 2004 were studied. Concentrations of thirteen PFASs and TSH were measured in plasma samples collected around the 18th week of gestation. Linear regression models were used to evaluate associations between PFASs and TSH. Results Among the thirteen PFASs, seven were detected in more than 60% of samples and perfluorooctane sulfonate (PFOS) had the highest concentrations (median, 12.8 ng/mL; inter-quartile range [IQR], 10.1 -16.5 ng/mL). The median TSH concentration was 3.5 (IQR, 2.4 - 4.8) ?IU/mL. Pregnant women with higher PFOS had higher TSH levels. After adjustment, with each 1 ng/mL increase in PFOS concentration, there was a 0.8% (95% confidence interval: 0.1%, 1.6%) rise in TSH. The odds ratio of having an abnormally high TSH, however, was not increased, and other PFASs were unrelated to TSH. Conclusions Our results suggest an association between PFOS and TSH in pregnant women that is small and may be of no clinical significance.

2013-01-01

82

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

83

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

SciTech Connect

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, S.; Morales, W.

1989-03-01

84

Complete amino acid sequencing and immunoaffinity clean-up can facilitate screening of various chemical modifications on human serum albumin.  

PubMed

This manuscript describes a simple and practical strategy for screening of various chemical modifications of human serum albumin (HSA). Serum albumin is the most abundant blood plasma protein in humans (HSA, 66.5 kDa, t1/2?=?19 d), constituting about 60 % of total proteins. Therefore, it is believed to be the main target of chemical stresses during physiological events such as increased oxidative stress from the degenerative diseases of aging, and higher glucose stress in diabetes mellitus. Consequently, chemical modifications can provide significant information about these biological events. In this study, a complete and robust sequencing method was attained by the peptide mass fingerprinting (PMF) technique using two different complementary proteases (trypsin and Glu-C) and matrix-assisted laser desorption ionization-time of flight/mass spectrometry (MALDI-TOF/MS) in both positive and negative ionization modes. Using this strategy, several modified peptides, 12 oxidations, 25 glycations, 6 lipoxidations, and 5 nitrations have been identified on HSA treated with chemical reactions in vitro. Combined with immunoaffinity clean-up, this method was able to detect in vivo chemical modifications of HSA and found oxidized Trp(214) and glycated Lys(525) in healthy human plasma. PMID:23846590

Goto, Takaaki; Murata, Kazuyuki; Lee, Seon Hwa; Oe, Tomoyuki

2013-09-01

85

Concentrations and patterns of perfluoroalkyl acids in Georgia, USA surface waters near and distant to a major use source  

USGS Publications Warehouse

Perfluoroalkyl acids (PFAAs) are widespread contaminants emanating from, among other sources, the production/degradation of fluorinated chemicals used in surface repellant applications, such as carpet manufacturing. The goal of the present study was to assess the concentrations of PFAAs, including perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUA), and perfluorooctane sulfonamide (PFOSA), in surface waters both near a wastewater land application system (LAS) in Dalton (GA, USA), home to North America's largest carpet manufacturing site, and distant to this location (Altamaha River, GA, USA) to understand the fate of PFAAs in freshwater. Levels of PFAAs were high in the Conasauga River (GA, USA) downstream of the LAS (PFOA, 253-1,150 ng/L; PFOS, 192-318 ng/L; PFNA, 202-369 ng/L; PFDA, 30.1-113 ng/L; PFUA, 58.0-99.2 ng/L; PFOSA, 162-283 ng/L) and in streams and ponds in Dalton (PFOA, 49.9-299 ng/L; PFOS, 15.8-120 ng/L), and were among the highest measured at a nonspill or directrelease location. Perfluoroalkyl acids in the Altamaha River were much lower (PFOA, 3.0-3.1 ng/L; PFOS, 2.6-2.7 ng/L), but were a source of PFAAs to Georgia's estuaries. A preliminary hazard assessment indicated that concentrations of PFOS at two sites in the Conasauga River exceeded the threshold effect predicted for birds consuming aquatic organisms that are exposed continuously to the PFOS levels at these sites. Assuming that toxicity for all PFAAs quantified is equal to that of PFOS, the sum total PFAAs at two sites within the Conasauga River exceeded PFOS thresholds for aquatic and avian species, warranting additional research. ?? 2008 SETAC Printed in the USA.

Konwick, B. J.; Tomy, G. T.; Ismail, N.; Peterson, J. T.; Fauver, R. J.; Higginbotham, D.; Fisk, A. T.

2008-01-01

86

Exceptionally high serum concentrations of perfluorohexanesulfonate in a Canadian family are linked to home carpet treatment applications.  

PubMed

Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are normally the dominant perfluoroalkyl substances (PFASs) in human serum, but here a Canadian family of seven was identified with particularly high exposure to perfluorohexanesulfonate (PFHxS). Disproportionately high serum PFHxS concentrations (range 27.5-423 ng/mL) and moderately high PFOS (range 15.2-108 ng/mL) and PFOA (range 2.40-9.23 ng/mL) concentrations were detected in the family members, with all three chemicals being highest in the youngest children. We therefore sought to identify the source(s) and pathway(s) of this unusual exposure, and to study the excretion of PFASs for this family. Serum, urine, and stool were sampled from family members, carpet, dust, and air were sampled in the home, and a questionnaire was administered. Over 15 years, the family's household carpets were treated 8 times with Scotchgard formulations. Elevated concentrations of PFHxS were detected in household dust (2780 ng/g dust) and in family room carpet (2880 ng/g carpet), and the primary mode of excretion for the major PFASs was through urine. The high PFHxS and moderately high PFOS concentrations in serum and household samples are consistent with the known PFAS content of certain Scotchgard formulations, and exposure was likely through dust ingestion and/or inhalation. PMID:23102093

Beesoon, Sanjay; Genuis, Stephen J; Benskin, Jonathan P; Martin, Jonathan W

2012-12-01

87

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) in consumer products in Norway - a pilot study.  

PubMed

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are used in numerous industrial and consumer products because of their special chemical properties, for instance the ability to repel both water and oil. A broad variety of PFAS have been introduced into the Norwegian market through industrial use (e.g. via fire fighting foams and paints) as well as in treated customer products such as textiles and coated paper. Our present knowledge of the exact chemical PFAS compositions in preparations using perfluorinated compounds is limited. This lack of knowledge means that it is difficult to provide an accurate assessment of human exposure to these compounds or to the amount of waste that may contain treated products. It is a growing concern that these potentially harmful compounds can now be found throughout the global environment. Samples of consumer products and preparations were collected in Norway, with supplemental samples from Sweden. In 27 of the 30 analyzed consumer products and preparations a number of polyfluorinated substances that were analyzed were detected but this does not exclude the occurrence of unknown PFAS. Notable was that perfluorooctanesulphonate (PFOS), which has been strictly regulated in Norway since 2007, was found in amounts close to or exceeding the EU regulatory level in 4 of the 30 analyzed products, all within the leather or carpet product groups. High amounts of fluorotelomer alcohols (FTOHs) were found in waterproofing agents, carpets and textiles, consistent with earlier findings by Fiedler et al. (2010). The presence of PFAS in a broad range of consumer products can give rise to a constant diffuse human exposure that might eventually result in harm to humans. PMID:22483730

Herzke, Dorte; Olsson, Elisabeth; Posner, Stefan

2012-08-01

88

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

PubMed

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

Mariussen, Espen

2012-09-01

89

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

PubMed

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

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

2014-02-01

90

Perfluoroalkyl substances in human milk: a first survey in Italy.  

PubMed

Due to their widespread diffusion, perfluoroalkyl substances (PFASs) have been frequently found in the environment and in several animal species. It has been demonstrated that they can easily reach also humans, mainly through diet. Being lactation a major route of elimination of these contaminants, their occurrence in human milk is of particular interest, especially considering that it generally represents the unique food source for newborns. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), the two most important compounds of this family, have been frequently found in human milk at variable concentrations, but still limited data are available. The present study, the first conducted in Italy capable to detect these pollutants at ultra-trace levels by UPLC-MS/MS, confirmed the role of lactation as a relevant source of exposure for breastfed children. The measured concentrations ranged between 15 and 288 ng/L for PFOS and between 24 and 241 ng/L for PFOA. Moreover, mean concentrations and frequencies of both analytes resulted higher in milk samples provided by primiparous women, suggesting that the risk of intake might be higher for first-borns. Finally, comparing these results with previous data, PFOS gradual decrease over time since year 2000 was confirmed. PMID:23138018

Barbarossa, Andrea; Masetti, Riccardo; Gazzotti, Teresa; Zama, Daniele; Astolfi, Annalisa; Veyrand, Bruno; Pession, Andrea; Pagliuca, Giampiero

2013-01-01

91

Analytical method for biomonitoring of perfluoroalkyl acids in human urine.  

PubMed

Perfluoroalkyl acids are an important class of synthetic compounds widely used in commercial and residential settings, which may have potential adverse health effects. The objective of this study was to monitor 6 perfluorocarboxylic acids and perfluorooctane sulphonate in human urine to obtain a way to asses exposure. The target analytes were extracted from urine by using a semi automated solid-phase extraction module and derivatised with isobutyl chloroformate by catalysis with 3% N,N-dicyclohexylcarbodiimide in pyridine. Determination and quantisation were achieved by gas chromatography with a mass spectrometer detector operating in the selected-ion monitoring mode. The developed approach is fast and provided low limits of detection (0.2-1.0ngL(-1)) with good precision (relative standard deviation lower than 7.5%, within-day and between day). Recoveries from urine samples, which were spiked with the studied compounds at levels of 10 and 50ngL(-1) ranged from 93% to 96%. Perfluorohexanoic (?70ngL(-1)) and perfluoroheptanoic acids (<2ngL(-1)) were found in the urine samples from exposed researchers taken after handling these compounds. From the calculation of the excretion kinetics it was found that the dosage absorbed was eliminated within 15h after exposure. PMID:25059141

Jurado-Sánchez, Beatriz; Ballesteros, Evaristo; Gallego, Mercedes

2014-10-01

92

Growth performance, carcass traits, meat chemical composition and blood serum metabolites of broiler chicken fed on diets containing flaxseed oil.  

PubMed

1. This study evaluated the effects of diets with partial and total substitution of soya bean oil (SO) with flaxseed (linseed) oil (FO) on broiler chicken performance, carcass traits, meat chemical composition and blood serum metabolites. 2. A total of 448 one-d-old Cobb 500 broiler chicken were used. They were allotted among 4 treatments with 8 replications, using a completely randomised design, for 35 d. Four diets were compared: T1 = 100% SO (3%, 1-7 d; 4%, 8-21 d; and 5%, 22-35 d); T2 = 50% SO + 50% FO; T3 = 25% SO + 75% FO and T4 = 100% FO. 3. No significant differences were observed in body weight (BW), body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and blood serum metabolites (total triglycerides, TRI; total cholesterol, CHO; high-density lipoprotein, HDL; low-density lipoprotein, LDL; glucose, GLU; albumin, ALB; globulin, GLO; and total proteins, TPs). Significant effects were observed for TRI, CHO, HDL, GLU, HDL, LDL, ALB and GLO with regard to the day of collection. 4. Carcass traits did not show significant differences for the treatments. No significant differences were observed for breast and drumstick chemical compositions, with the exception of drumstick fat concentration (quadratic effect). 5. In conclusion, the partial or total substitution of SO with FO did not affect growth performance, carcass traits, meat chemical composition or blood serum profile in broiler chicken. Therefore, FO can be an alternative to SO in the diet formulation for broiler chicken. PMID:24397514

Lopes, D C N; Xavier, E G; Santos, V L; Gonçalves, F M; Anciuti, M A; Roll, V F B; Del Pino, F A B; Feijó, J O; Catalan, A A S

2013-01-01

93

Umbilical cord blood levels of perfluoroalkyl acids and polybrominated flame retardants.  

PubMed

Perfluoroalkyl acids (PFAAs) and polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants representing two classes of environmental contaminants of toxicological concern, especially for infants. Canadian biomonitoring data on these chemicals are limited. The objectives of this study were to measure PFAAs and PBDEs in umbilical cord blood from approximately 100 hospital deliveries in Ottawa (Ontario, Canada) and examine associations with characteristics of the mother and infant. Geometric means were 1.469 ng/mL for perfluorooctanoate (PFOA) (95% confidence interval of 1.292-1.671 ng/mL), 4.443 ng/mL for perfluorooctane sulfonate (PFOS) (95% CI of 3.735-5.285 ng/mL), 0.359 ng/mL for perfluorononanoic acid (PFNA) (95% CI of 0.318-0.404 ng/mL), and 0.579 ng/mL for perfluorohexanesulfonate (PFHxS) (95% CI of 0.473-0.709 ng/mL). The final multiple regression models indicated that lower gravida, term gestational age, smoking during pregnancy and vaginal delivery were significantly associated with higher levels of PFOS. Similarly, a vaginal delivery was significantly associated with higher PFOA, while weak associations were found with lower gravida and birth weight less than 2500 g. Furthermore, higher PFNA concentrations were significantly associated with older mothers, and vaginal delivery, while weakly associated with term gestational age. Elevated PFHxS concentrations were significantly associated with smoking during pregnancy and lower gravida. Similar to reports from other countries, the preponderant PBDE congener measured in the cord blood was PBDE-47. Questions remain on why various studies have reported conflicting results on the association between PFAAs and birth weight. PMID:22494936

Arbuckle, Tye E; Kubwabo, Cariton; Walker, Mark; Davis, Karelyn; Lalonde, Kaela; Kosarac, Ivana; Wen, Shi Wu; Arnold, Douglas L

2013-03-01

94

Chemical modification of siRNAs to improve serum stability without loss of efficacy  

Microsoft Academic Search

Development of RNA interference as a novel class of therapeutics requires improved pharmacokinetic properties of short interfering RNA (siRNA). To confer enhanced serum stability to Sur10058, a hyperfunctional siRNA which targets survivin mRNA, a systematic modification at the 2?-sugar position and phosphodiester linkage was introduced into Sur10058. End modification of three terminal nucleotides by 2?-OMe and phosphorothioate substitutions resulted in

Sorim Choung; Young Joo Kim; Seonhoe Kim; Han-Oh Park; Young-Chul Choi

2006-01-01

95

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

EPA Science Inventory

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

96

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...

97

Evaluation of the fate of perfluoroalkyl compounds in wastewater treatment plants  

Microsoft Academic Search

Recent studies have shown that the wastewater treatment plant (WWTP) is a significant source of perfluoroalkyl compounds (PFCs) in natural water. In this study, 10 PFCs were analyzed in influent and effluent wastewater and sludge samples in 15 municipal, 4 livestock and 3 industrial WWTPs in Korea. The observed distribution pattern of PFCs differed between the wastewater and sludge samples.

Rui Guo; Won-Jin Sim; Eung-Sun Lee; Ji-Hyun Lee; Jeong-Eun Oh

2010-01-01

98

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

Microsoft Academic Search

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.

R. C. Buck; J. F. Franklin; U. Berger; J. M. Conder; I. T. Cousins; Voogt de P; A. A. Jensen; K. Kannan; S. A. Mabury; Leeuwen van S. P. J

2011-01-01

99

Perfluoroalkyl and polyfluoralkyl substances (PFASs) in the environment: terminology, classification, and origins  

Microsoft Academic Search

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.

R. C. Buck; J. Franklin; U. Berger; J. M. Conder; I. T. Cousins; Voogt de P; A. A. Jensen; K. Kannan; S. A. Mabury; Leeuwen van S. P. J

2011-01-01

100

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

101

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.

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

102

Perfluoroalkyl acids in marine organisms from Lake Shihwa, Korea.  

PubMed

To our knowledge, this is the first report of concentrations of perfluorooctanesulfonate (PFOS) and other perfluoroalkyl acids (PFAs) in marine organisms from the industrialized region of Korea. Concentrations of eight PFAs were determined in three species of fish (mullet, shad, and rockfish) and three species of marine invertebrates (blue crab, oyster, and mussel) from Lake Shihwa, Korea. This is an area in which relatively great concentrations of PFAs in water and in adjacent industrial effluents have been reported. PFOS was the dominant PFA in marine organisms and most PFOS concentrations were greater than the sum of all other PFAs. The mean concentrations of PFOS were 8.1 x 10 and 3.6 x 10 ng/g, wet weight in liver and blood of fish, respectively. Perfluorocarboxylic acids (PFCAs) were also found in fish, but their concentrations were 10-fold less than those for PFOS. Of the PFCAs measured in fish, concentrations of the longer-chain perfluoroundecanoic acid (PFUnA) were the greatest. Concentrations of PFOS in soft tissues of blue crabs decreased as a function of distance from the shore where inputs from the industrialized areas are discharged into Lake Shihwa. PFOS was the only PFA detectable in mussels and oysters with a mean of 0.5 +/- 0.2 and 1.1 +/- 0.3 ng/g, wet weight, respectively. Concentrations of PFUnA were positively correlated with perfluorodecanoic acid (PFDA) in both the liver and blood of fish, which suggests a common source of these two PFCAs in this area. Hazard quotients developed for fish species were all less than 1.0 for fish collected in Lake Shihwa. PMID:19152061

Yoo, Hoon; Yamashita, Nobuyoshi; Taniyasu, Sachi; Lee, Kyu Tae; Jones, Paul D; Newsted, John L; Khim, Jong Seong; Giesy, John P

2009-10-01

103

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

PubMed

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

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

2013-10-01

104

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...

105

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.

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

2014-01-01

106

Perfluoroalkyl acids and the isomers of perfluorooctanesulfonate and perfluorooctanoate in the sera of 50 new couples in Tianjin, China.  

PubMed

A total of 100 serum samples from 50 new couples (none of the females in this study has ever been pregnant) in Tianjin, North China, were analyzed for eleven perfluoroalkyl acids (PFAAs) with isomer-specific method. Among all samples, total perfluorooctanesulfonate (?PFOS, mean 11.3 ng/mL) was predominant followed by total perfluorooctanoate (?PFOA, 2.95 ng/mL), perfluorodecanoate (PFDA, 1.17 ng/mL), perfluorononanoate (PFNA, 0.93 ng/mL) and perfluorohexanesulfonate (PFHxS, 0.67 ng/mL). The mean concentrations of ?PFOS and PFHxS in males (14.2 and 0.89 ng/mL) were significantly higher (p=0.001) than in females (8.36 and 0.45 ng/mL). No statistical difference between genders was observed for the other PFAAs. This suggests that menstruation is one important elimination pathway for ?PFOS and PFHxS in females. Linear PFOA was the dominant isomer with mean proportion of 99.7%, suggesting that telomeric PFOA (and its precursors), which contains almost pure linear isomer, might be the dominant exposure source of PFOA in Tianjin. On average, the proportion of linear PFOS (n-PFOS) was 59.2% of ?PFOS, which was lower than that in technical PFOS products (ca. 70% linear). Except perfluoroisopropyl PFOS, all the other monomethyl branched PFOS isomers were enriched in human serum compared to the commercial products, suggesting the monomethyl branched PFOS precursors were preferentially biotransformed in humans. PMID:24747327

Zhang, Yifeng; Jiang, Weiwei; Fang, Shuhong; Zhu, Lingyan; Deng, Jimin

2014-07-01

107

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

108

Reactions of chlorine and bromine fluorosulfates with perfluoroalkyl halides in a strongly acidic medium  

SciTech Connect

The authors find that in HSO/sub 3/F medium containing SbF/sub 5/ (preferably ca 20-40%), already at a temperature much lower than O C, ClOSO/sub 2/F exothermally substitutes bromine in 1,2-dibromotetrafluoroethane, leading to 1,2-bis(fluorosulfonxyloxy)tetrafluoroethane (I) in a high yield (greater than 80%). Bromine fluorosulfate BrOSO/sub 2/F was found to be less active than ClOSO/sub 2/F with respect to 1,2-dibromotetrafluoroethane in both the presence and in absence of the HSO/sub 3/F/SbF/sub 5/ mixture. In a fluorosulfonic acid medium containing antimony pentafluoride, the reaction with chlorine fluorosulfate leads to the substitution of the primary chlorine atom in perfluoroalkyl chlorides, and also the primary and secondary bromine atoms in perfluoroalkyl bromides by the fluorosulfate group under mild conditions.

Fokin, A.V.; Rapkin, A.I.; Seryanov, Y.V.; Studnev, Y.N.; Tatarinov, A.S.

1986-01-01

109

Tribological reactions of perfluoroalkyl polyether oils with stainless steel under ultrahigh vacuum conditions at room temperature  

NASA Technical Reports Server (NTRS)

The reaction between three types of commercial perfluoroalkyl polyether (PFPE) oils and stainless steel 440C was investigated experimentally during sliding under ultrahigh vacuum conditions at room temperature. It is found that the tribological reaction of PFPE is mainly affected by the activity of the mechanically formed fresh surfaces of metals rather than the heat generated at the sliding contacts. The fluorides formed on the wear track act as a boundary layer, reducing the friction coefficient.

Mori, Shigeyuki; Morales, Wilfredo

1989-01-01

110

Reductive degradation of perfluoroalkyl compounds with aquated electrons generated from iodide photolysis at 254 nm.  

PubMed

The perfluoroalkyl compounds (PFCs), perfluoroalkyl sulfonates (PFXS) and perfluoroalkyl carboxylates (PFXA) are environmentally persistent and recalcitrant towards most conventional water treatment technologies. Here, we complete an in depth examination of the UV-254 nm production of aquated electrons during iodide photolysis for the reductive defluorination of six aquated perfluoroalkyl compounds (PFCs) of various headgroup and perfluorocarbon tail length. Cyclic voltammograms (CV) show that a potential of +2.0 V (vs. NHE) is required to induce PFC oxidation and -1.0 V is required to induce PFC reduction indicating that PFC reduction is the thermodynamically preferred process. However, PFCs are observed to degrade faster during UV(254 nm)/persulfate (S(2)O(8)(2-)) photolysis yielding sulfate radicals (E° = +2.4 V) as compared to UV(254 nm)/iodide (I(-)) photolysis yielding aquated electrons (E° = -2.9 V). Aquated electron scavenging by photoproduced triiodide (I(3)(-)), which achieved a steady-state concentration proportional to [PFOS](0), reduces the efficacy of the UV/iodide system towards PFC degradation. PFC photoreduction kinetics are observed to be dependent on PFC headgroup, perfluorocarbon chain length, initial PFC concentration, and iodide concentration. From 2 to 12, pH had no observable effect on PFC photoreduction kinetics, suggesting that the aquated electron was the predominant reductant with negligible contribution from the H-atom. A large number of gaseous fluorocarbon intermediates were semi-quantitatively identified and determined to account for ?25% of the initial PFOS carbon and fluorine. Reaction mechanisms that are consistent with kinetic observations are discussed. PMID:22025132

Park, Hyunwoong; Vecitis, Chad D; Cheng, Jie; Dalleska, Nathan F; Mader, Brian T; Hoffmann, Michael R

2011-12-01

111

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

112

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

113

Serum low density lipoprotein of alcoholic patients is chemically modified in vivo and induces apolipoprotein E synthesis by macrophages.  

PubMed Central

This work was carried out to investigate the effect of alcohol drinking on serum LDL. Agarose gel electrophoresis showed that LDL samples from alcoholic patients without serious liver disease were more negatively charged and moved faster toward the cathode than LDL from nondrinking control subjects. Rabbit antibodies raised by using keyhole limpet hemocyanin modified in vitro by 4-hydroxynonenal or by acetaldehyde as immunogens reacted more strongly with patients' LDL than with control LDL, indicating the presence of oxidatively modified epitopes and acetaldehyde adducts in alcoholic patients' LDL. LDL of alcoholic patients has decreased vitamin E contents. The electromobility of LDL decreased after abstinence from alcohol and returned to normal in 2 wk, but this was not accompanied by a significant increase in its vitamin E contents. When incubated with mouse peritoneal macrophages, patients' LDL induced apolipoprotein E secretion by threefold over control LDL with a concomitant increase in cellular cholesterol. Our results thus demonstrate that LDL of alcoholic patients has lower vitamin E content, is chemically modified in vivo, and exhibits altered biological function. These changes in heavy alcoholic drinkers may render LDL more atherogenic and thereby may counter the antiatherosclerosis effects of moderate alcohol consumption. Images

Lin, R C; Dai, J; Lumeng, L; Zhang, M Y

1995-01-01

114

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.

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

2014-01-01

115

Methods for the identification of chemical respiratory allergens in rodents: comparisons of cytokine profiling with induced changes in serum IgE.  

PubMed

No validated or widely recognized test methods are currently available for the prospective identification of chemicals with the potential to cause respiratory allergy. The cellular and molecular mechanisms that result in the induction of chemical sensitization of the respiratory tract are unclear, although there is evidence for the selective development of T helper 2 (Th2)-type responses and, in some cases, the production of IgE antibody. We have therefore examined the utility of cytokine profiling using BALB/c mice, together with the measurement of induced increases in the total serum concentration of IgE in the Brown Norway (BN) rat, as markers for the prospective identification of chemical respiratory allergens. Responses provoked by the reference respiratory allergen trimellitic anhydride (TMA) have been compared with those stimulated by the respiratory sensitizing diisocyanates toluene diisocyanate (TDI) and hexamethylene diisocyanate (HDI) and by the acid anhydride hexahydrophthalic anhydride (HHPA). Topical exposure of BN rats to TMA, TDI and HHPA each provoked marked immune activation (increases in lymph node cellularity and proliferation). However, only treatment with TMA stimulated vigorous increases in the total serum concentration of IgE. In contrast, exposure to HHPA, TDI or HDI failed to provoke significant changes in serum IgE concentration or induced only transient and relatively weak increases in serum IgE levels. In parallel experiments using BALB/c strain mice, however, topical application of all four chemical respiratory allergens provoked a marked Th2-type cytokine secretion profile in draining lymph node cells. These data suggest that the measurement of induced changes in serum IgE is not sufficiently sensitive for the robust identification of chemical respiratory allergens. Furthermore, irrespective of the reasons for variations in TMA-induced IgE production among BN rats, doubts remain regarding the utility of these animals for the characterization of immune responses to chemical allergens. Cytokine profiling using the BALB/c strain mouse apparently provides a more robust method for the hazard assessment of chemical respiratory allergens. PMID:12884401

Dearman, R J; Skinner, R A; Humphreys, N E; Kimber, I

2003-01-01

116

Quantification of serum C-peptide by isotope-dilution liquid chromatography-tandem mass spectrometry: enhanced detection using chemical modification and immunoaffinity purification.  

PubMed

A method was developed to quantify human serum C-peptide by isotope-dilution mass spectrometry (ID MS). This new approach used immunoaffinity purification and chemical modification to improve the sensitivity which covered the wide range of reference interval of serum C-peptide. The immunoaffinity purification was performed using monoclonal antibody against human C-peptide that was immobilized on magnetic beads, and the purified C-peptide was chemically modified using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) prior to liquid chromatography-tandem mass spectrometry (LC-MS/MS). With this method, the LC-MS/MS peak area increased 23-fold compared with the conventional purification by solid-phase extraction and without chemical modification. The limit of quantification was estimated to be 0.003ng on column, which was lower than previously reported. The validation study showed that (1) the response in the 0.003-2.9ng range on column was linear (regression coefficient, r(2)=0.9994), (2) the relative standard deviation (RSD) within and between days was inferior to 4.0%, and (3) the spike and recovery test showed the mean recoveries ranging between 99% and 108%. Comparison with an established commercial immunoassay showed high correlation (r(2)=0.9994) at serum concentration of 0.19-8.49ng/mL. These assessments suggest that this ID MS-based approach can quantify human serum C-peptide with high sensitivity and precision in the reference interval and find a potential use in the reference measurement procedure of serum C-peptide, allowing traceable measurement. This method may also generally be applied to peptide quantification in biological fluids with high sensitivity. PMID:24607695

Kinumi, Tomoya; Mizuno, Ryoko; Takatsu, Akiko

2014-03-15

117

Thyroxine is the serum factor that regulates morphogenesis of columnar cartilage from isolated chondrocytes in chemically defined medium  

Microsoft Academic Search

Epiphyseal chondrocytes cultured in a medium containing 10% serum may be maintained as three dimensional aggregates and differentiate termi- nally into hypertrophic cells. There is an attendant ex- pression of genes encoding type X collagen and high levels of alkaline phosphatase activity. Manipulation of the serum concentration to optimal levels of 0.1 or 0.01% in this chondrocyte pellet culture system

R. Tracy Ballock; A. H. Reddi

1994-01-01

118

Carbonate and fluoride incorporation in synthetic apatites: Comparative effect on physico-chemical properties and in vitro bioactivity in fetal bovine serum  

Microsoft Academic Search

CO3- and\\/or F-substituted apatites have been considered as potential bone substitution material for dental and orthopedic applications. The objective of this study was to compare physico-chemical properties and invitro bioactivity in fetal bovine serum (FBS) of apatites containing CO3 and\\/or F. The results showed that CO3 and F in apatites have opposite effects on crystallinity and solubility. Calcium deficient hydroxyapatite

Fang Yao; Racquel Z. LeGeros

2010-01-01

119

Oxidative conversion as a means of detecting precursors to perfluoroalkyl acids in urban runoff.  

PubMed

A new method was developed to quantify concentrations of difficult-to-measure and unidentified precursors of perfluoroalkyl carboxylic (PFCA) and sulfonic (PFSA) acids in urban runoff. Samples were exposed to hydroxyl radicals generated by thermolysis of persulfate under basic pH conditions and perfluoroalkyl acid (PFAA) precursors were transformed to PFCAs of related perfluorinated chain length. By comparing PFCA concentrations before and after oxidation, the concentrations of total PFAA precursors were inferred. Analysis of 33 urban runoff samples collected from locations around the San Francisco Bay, CA indicated that PFOS (2.6-26 ng/L), PFOA (2.1-16 ng/L), and PFHxA (0.9-9.7 ng/L) were the predominant perfluorinated compounds detected prior to sample treatment. Following oxidative treatment, the total concentrations of PFCAs with 5-12 membered perfluoroalkyl chains increased by a median of 69%, or between 2.8 and 56 ng/L. Precursors that produced PFHxA and PFPeA upon oxidation were more prevalent in runoff samples than those that produced PFOA, despite lower concentrations of their corresponding perfluorinated acids prior to oxidation. Direct measurements of several common precursors to PFOS and PFOA (e.g., perfluorooctanesulfonamide and 8:2 fluorotelomer sulfonate) accounted for less than 25% of the observed increase in PFOA, which increased by a median value of 37%. Exposure of urban runoff to sunlight, advanced oxidation processes, or microbes could result in modest, but measurable, increases in concentrations of PFCAs and PFSAs. PMID:22900587

Houtz, Erika F; Sedlak, David L

2012-09-01

120

40 CFR 721.9582 - Certain perfluoroalkyl sulfonates.  

Code of Federal Regulations, 2012 CFR

...Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES...anodizing; nickel, cadmium, or lead plating; metal plating on plastics; and alkaline zinc plating. (5) Manufacture...

2012-07-01

121

40 CFR 721.9582 - Certain perfluoroalkyl sulfonates.  

Code of Federal Regulations, 2011 CFR

...Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES...anodizing; nickel, cadmium, or lead plating; metal plating on plastics; and alkaline zinc plating. (5) Manufacture...

2011-07-01

122

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 (...

123

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.

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

2011-01-01

124

Estrogen-like activity of perfluoroalkyl acids in vivo and interaction with human and rainbow trout estrogen receptors in vitro.  

PubMed

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 (IC(50)) 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 10-1000 nM. 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

2011-03-01

125

Induced changes in total serum IgE concentration in the Brown Norway rat: potential for identification of chemical respiratory allergens.  

PubMed

A variety of chemicals can cause sensitization of the respiratory tract and occupational asthma that may be associated with IgE antibody production. Topical exposure to chemical respiratory allergens such as trimellitic anhydride (TMA) has been shown previously to induce increases in the total serum concentration of IgE in BALB/c strain mice. Contact allergens such as 2,4-dinitrochlorobenzene (DNCB), which apparently lack respiratory sensitizing potential, fail to provoke similar changes. However, it became apparent with time that there was some inter-animal variation in constitutive and inducible IgE levels. We have now examined the influence of topical exposure to TMA and DNCB on serum IgE levels in the Brown Norway (BN) rat. Such animals can be bled serially and thus it is possible to perform longitudinal analyses of changes in serum IgE concentration. The kinetics of IgE responses therefore can be followed on an individual animal basis, allowing discrimination between transient and sustained increases in serum IgE concentration. Rats (n = 5) were exposed on shaved flanks to 50% TMA, to 1% DNCB (concentrations that elicit comparable immune activation with respect to draining lymph node cellularity and proliferation) or to vehicle alone. Total IgE was measured by enzyme-linked immunosorbent assay in serum samples taken prior to and 14-42 days following initial exposure. Those animals having high pre-existing IgE levels (>1.0 microg ml(-1)) were excluded from subsequent analyses. The levels of serum IgE in the majority of rats exposed to DNCB or vehicle alone remained relatively stable throughout the duration of all the experiments conducted, although some animals displayed transient increases in serum IgE. Only TMA treatment was associated with a significant and sustained increase in the level of serum IgE in the majority of experiments. The elevated concentrations of IgE induced by topical exposure to TMA are persistent, the results reported here demonstrating that induced changes in IgE are maximal or near maximal at approximately 35 days, with a significant increase in IgE demonstrable for at least 42 days following the initiation of exposure. Interestingly, although TMA and DNCB at the test concentrations used were found to be of comparable overall immunogenicity with regard to lymph node activation and the induction of lymph node cell proliferation, there were apparent differences in humoral immune responses. Thus, not only did exposure to TMA stimulate increases in total serum IgE concentration and the production of specific IgE antibody, but also a more vigorous IgG antibody response was provoked by TMA compared with DNCB. These data suggest that the measurement of induced changes in serum IgE concentration in the BN strain of rat is able to differentiate between different classes of chemical allergen. Given the inter-animal variation in IgE production, it would be prudent to incorporate a concurrent assessment of responses induced by treatment with TMA as a positive control against which to assess the activity of other test materials. PMID:11807923

Warbrick, E V; Dearman, R J; Kimber, I

2002-01-01

126

Enhancement of atmospheric pressure chemical ionization for the determination of free and glycine-conjugated bile acids in human serum.  

PubMed

A highly sensitive and accurate method based on the precolumn derivatization of bile acids (BA) with a high ionization efficiency labeling reagent 1,2-benzo-3,4-dihydrocarbazole-9-ethyl-benzenesulfonate (BDEBS) coupled with LC/MS has been developed. After derivatization, BA molecules introduced a weak basic nitrogen atom into the molecular core structure that was readily ionized in commonly used acidic HPLC mobile phases. Derivatives were sufficiently stable to be efficiently analyzed by atmospheric pressure chemical ionization (APCI)-MS/MS in positive-ion mode. The MS/MS spectra of BA derivatives showed an intense protonated molecular ion at m/z [M + H]+. The collision-induced dissociation of the molecular ion produced fragment ions at [MH-H2O]+, [MH-2H2O]+, [MH-3H2O]+. The characteristic fragment ions were at m/z 320.8, 262.8, and 243.7 corresponding to a cleavage of N-CO, O-CO, and C-OCO, respectively, and bonds of derivatized molecules. The selected reaction monitoring, based on the m/z [M+H]+ --> [MH-H2O]+, [MH-2H2O]+, [MH-3H2O]+, 320.8, 262.8, and 243.7 transitions, was highly specific for the BA derivatives. The LODs for APCI in a positive-ion mode, at an S/N of 5, were 44.36-153.6 fmol. The validation results showed high accuracy in the range of 93-107% and the mean interday precision for all standards was <15% at broad linear dynamic ranges (0.0244-25 nmol/mL). Good linear responses were observed with coefficients of > 0.9935 in APCI/MS detection. Therefore, the facile BDEBS derivatization coupled with mass spectrometric analysis allowed the development of a highly sensitive and specific method for the quantitation of trace levels of the free and glycine-conjugated BA from human serum samples. PMID:17305246

You, Jinmao; Shi, Yunwei; Zhao, Xianen; Zhang, Haifeng; Suo, Yourui; Yulin, L; Wang, Honglun; Sun, Jing

2006-12-01

127

Preliminary Lists of PFOS, PFAS, PFOA and Related Compounds and Chemicals that May Degrade to PFCA  

Microsoft Academic Search

The OECD conducted a survey in 2004 on Perfluorooctane Sulfonate (PFOS), Perfluoroalkyl Sulfonate (PFAS), Perfluorooctanoic Acid (PFOA), related substances and products\\/mixtures containing these substances within OECD and non-OECD member countries. The information sought were quantities manufactured or imported, concentration of the chemicals in the products or mixtures, uses, use in consumer products, availability of alternatives or substitutes and essential uses

2006-01-01

128

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

PubMed

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

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

2012-07-01

129

Grafting of perfluoroalkyl chains onto wood using blocked isocyanates  

Microsoft Academic Search

Chemical modification of wood was investigated using blocked isocyanates prepared from reaction of 4,4?-diphenylmethane diisocyanate (MDI) with 1 equivalent of 2-perfluorohexyl ethanol followed by addition of 1.1 equivalent of methyl ethyl ketoxime (MEKO). Thermal dissociation of the urethane linkage bearing a methyl ethyl ketoxime group allows generation of free isocyanate which reacts with alcohols like cyclohexanol or benzyl alcohol. The

Prosper Edou Engonga; Véronique Marchetti; Philippe Gérardin; Piotr Tekely; Bernard Loubinoux

2000-01-01

130

Design and chemical synthesis of iodine-containing molecules for application to solar-pumped I* lasers  

NASA Technical Reports Server (NTRS)

This work is directed toward the design and chemical synthesis of new media for solar-pumped I* lasers. In view of the desirability of preparing a perfluoroalkyl iodide absorbing strongly at 300 nm, the relationship betwen perfluoroalkyl iodide structure and the corresponding absorption wavelength was reexamined. Analysis of existing data suggests that, in this family of compounds, the absorption maximum shifts to longer wavelength, as desired, as the C-I bond in the lasant is progressively weakened. Weakening of the C-I bond correlates, in turn, with increasing stability of the perfluoroalkyl radical formed upon photodissociation of the iodide. The extremely promising absorption characteristics of perfluoro-tert-butyl iodide can be accounted for on this basis. A new technique of diode laser probing to obtain precise yields of I* atoms in photodissociation was also developed.

Shiner, C. S.

1985-01-01

131

Amphiphilic perfluoroalkyl carbohydrates as new tools for liver imaging.  

PubMed

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

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

2009-09-11

132

Chemical and Biological Properties of B16 Murine Melanoma Cells Grown in Defined Medium Containing Bovine Serum Albumin1  

Microsoft Academic Search

SUMMARY The addition of 1% (w\\/v) bovine serum albumin (BSA) to the F12 medium utilized for the growth of the B16 mela noma cells significantly stimulated the growth of this cell line. The synthesis of mucopolysaccharides and sialogly- copeptides in this medium is identical with that in Eagle's minimal essential medium with Earle's balanced salt solu tion supplemented with 2

John R. Banks; V. P. Bhavanandan; E. A. Davidson

1977-01-01

133

LC-MS analysis of estradiol in human serum and endometrial tissue: Comparison of electrospray ionization, atmospheric pressure chemical ionization and atmospheric pressure photoionization.  

PubMed

Accurate measurement of estradiol (E2) is important in clinical diagnostics and research. High sensitivity methods are critical for specimens with E2 concentrations at low picomolar levels, such as serum of men, postmenopausal women and children. Achieving the required assay performance with LC-MS is challenging due to the non-polar structure and low proton affinity of E2. Previous studies suggest that ionization has a major role for the performance of E2 measurement, but comparisons of different ionization techniques for the analysis of clinical samples are not available. In this study, female serum and endometrium tissue samples were used to compare electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) in both polarities. APPI was found to have the most potential for E2 analysis, with a quantification limit of 1 fmol on-column. APCI and ESI could be employed in negative polarity, although being slightly less sensitive than APPI. In the presence of biological background, ESI was found to be highly susceptible to ion suppression, while APCI and APPI were largely unaffected by the sample matrix. Irrespective of the ionization technique, background interferences were observed when using the multiple reaction monitoring transitions commonly employed for E2 (m/z 271?>?159; m/z 255?>?145). These unidentified interferences were most severe in serum samples, varied in intensity between ionization techniques and required efficient chromatographic separation in order to achieve specificity for E2. PMID:24078246

Keski-Rahkonen, Pekka; Huhtinen, Kaisa; Desai, Reena; Harwood, D Tim; Handelsman, David J; Poutanen, Matti; Auriola, Seppo

2013-09-01

134

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

135

Spontaneous three-dimensional nanostructure formation of perfluoroalkyl terminated liquid crystal: A molecular dynamics simulation study  

NASA Astrophysics Data System (ADS)

Structure formation of a perfluoroalkyl terminated liquid crystal molecule was studied by molecular dynamics simulations. Two distinct structures with smectic-C-like layers and with bundles (blocks) of collapsed layers were spontaneously formed depending on the simulation temperatures. The bundles in the latter structure were somewhat positionally ordered (with respect to the small angle spots in its structure function) and orientationally isotropic overall even though the molecules making each bundle were well oriented. These characteristics of the simulated system well correspond to the cubic phase of the real system, and an even more precisely correspond to the proposed cubic structure model [M. Yoneya, E. Nishikawa, and H. Yokoyama, J. Chem. Phys. 120, 3699 (2004)] with respect to its hierarchical structure.

Yoneya, Makoto; Nishikawa, Etsushi; Yokoyama, Hiroshi

2004-10-01

136

Comparison of yields of stable perfluoroalkyl radicals in gamma and neutron radiolysis  

SciTech Connect

In the irradiation of liquid perfluoro-1-methyl-4-isoburylcyclohexane (MBC) with Co-60 gamma rays, stable perfluoroalkyl radicals are formed. This paper shows the dependence on dose of the concentration of stable radicals formed during the irradiation of MBC with Co-60 gamma rays at 300 degrees K. The EPR spectra of these radicals show a doublet and a triplet with splitting at 3.9 and 5.6 mT, respectively. On the basis of perfluoro compounds like MBC it is possible to create dosimetric systems with which the dose of gamma-irradiation can be determined against a background stream of fast neutrons, simply by measuring the concentration of stabilized radicals.

Allayarov, S.R.; Barkalov, I.M.; Gol'danskii, V.I.; Zuev, A.P.

1985-09-01

137

Occurrence of perfluoroalkyl compounds in surface waters from the North Pacific to the Arctic Ocean.  

PubMed

Perfluoroalkyl compounds (PFCs) were determined in 22 surface water samples (39-76°N) and three sea ice core and snow samples (77-87°N) collected from North Pacific to the Arctic Ocean during the fourth Chinese Arctic Expedition in 2010. Geographically, the average concentration of ?PFC in surface water samples were 560 ± 170 pg L(-1) for the Northwest Pacific Ocean, 500 ± 170 pg L(-1) for the Arctic Ocean, and 340 ± 130 pg L(-1) for the Bering Sea, respectively. The perfluoroalkyl carboxylates (PFCAs) were the dominant PFC class in the water samples, however, the spatial pattern of PFCs varied. The C(5), C(7) and C(8) PFCAs (i.e., perfluoropentanoate (PFPA), perfluoroheptanoate (PFHpA), and perfluorooctanoate (PFOA)) were the dominant PFCs in the Northwest Pacific Ocean while in the Bering Sea the PFPA dominated. The changing in the pattern and concentrations in Pacific Ocean indicate that the PFCs in surface water were influenced by sources from the East-Asian (such as Japan and China) and North American coast, and dilution effect during their transport to the Arctic. The presence of PFCs in the snow and ice core samples indicates an atmospheric deposition of PFCs in the Arctic. The elevated PFC concentration in the Arctic Ocean shows that the ice melting had an impact on the PFC levels and distribution. In addition, the C(4) and C(5) PFCAs (i.e., perfluorobutanoate (PFBA), PFPA) became the dominant PFCs in the Arctic Ocean indicating that PFBA is a marker for sea ice melting as the source of exposure. PMID:22128794

Cai, Minghong; Zhao, Zhen; Yin, Zhigao; Ahrens, Lutz; Huang, Peng; Cai, Minggang; Yang, Haizhen; He, Jianfeng; Sturm, Renate; Ebinghaus, Ralf; Xie, Zhiyong

2012-01-17

138

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

139

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

PubMed

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

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

2014-08-01

140

Design and chemical synthesis of iodine-containing molecules for application to solar-pumped I* lasers. Semiannual Progress Report, 1 January-30 June 1985  

SciTech Connect

This work is directed toward the design and chemical synthesis of new media for solar-pumped I* lasers. In view of the desirability of preparing a perfluoroalkyl iodide absorbing strongly at 300 nm, the relationship betwen perfluoroalkyl iodide structure and the corresponding absorption wavelength was reexamined. Analysis of existing data suggests that, in this family of compounds, the absorption maximum shifts to longer wavelength, as desired, as the C-I bond in the lasant is progressively weakened. Weakening of the C-I bond correlates, in turn, with increasing stability of the perfluoroalkyl radical formed upon photodissociation of the iodide. The extremely promising absorption characteristics of perfluoro-tert-butyl iodide can be accounted for on this basis. A new technique of diode laser probing to obtain precise yields of I* atoms in photodissociation was also developed.

Shiner, C.S.

1985-01-01

141

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

PubMed

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

Strøm, Marin; Hansen, Susanne; Olsen, Sjúrður Fróði; Haug, Line Småstuen; Rantakokko, Panu; Kiviranta, Hannu; Halldorsson, Thorhallur Ingi

2014-07-01

142

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

143

Photoinduced diastereoselective addition of perfluoroalkyl iodides to acrylic acid derivatives for the synthesis of fluorinated amino acids.  

PubMed

Photoinduced diastereoselective addition of perfluoroalkyl iodides in the presence of an aqueous solution of Na2S2O3 was an excellent method for iodoperfluoroalkylation of acrylic acid derivatives bearing a chiral auxiliary, with moderate to good stereoselectivities and with no detectable side products. The iodoperfluoroalkylation of N-acyloylcamphorsultam provided a convenient route for preparing chiral fluorine-containing amino acids. PMID:17542595

Yajima, Tomoko; Nagano, Hajime

2007-06-21

144

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

145

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

146

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

PubMed

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

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

2013-09-01

147

IgG antibody against formaldehyde human serum proteins: A comparison with other IgG antibodies against inhalant proteins and reactive chemicals  

SciTech Connect

Immune responses to formaldehyde (F) have been recorded for seven decades. More recently, sensitive assays for antibody against F-human serum albumin (HSA) have been reported. IgG antibody against F-HSA has been said to correlate with symptoms against F-HSA. We report on 61 serum samples analyzed for IgG antibodies against F-HSA. IgG antibodies against F-HSA were most prevalent in subjects who had received intravenous F. In no case (either presumed symptomatic to F or with IgG antibody against F-HSA) was there a correlation of serologic results with symptoms. We also reviewed inhalation disease caused by chemicals and proteins acting as immunogens and report that at this time there is no evidence that gaseous F meets the criteria for causation of inhalational IgG-mediated lung disease by clinical or serologic studies. Very high IgG antibody levels occur in respiratory immunologic inhalational disease, and the absence of these high IgG levels against F is strong evidence against F or F proteins being an inhalational antigen of significance.

Patterson, R.; Dykewicz, M.S.; Evans, R. 3d.; Grammer, L.C.; Greenberger, P.A.; Harris, K.E.; Lawrence, I.D.; Pruzansky, J.J.; Roberts, M.; Shaughnessy, M.A. (Northwestern Univ. Medical School, Chicago, IL (USA))

1989-09-01

148

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

PubMed

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

Gagyi, László; Gyéresi, Arpád; Kilár, Ferenc

2006-04-01

149

Pre-natal exposure to perfluoroalkyl substances may be associated with altered vaccine antibody levels and immune-related health outcomes in early childhood.  

PubMed

Perfluoroalkyl substances (PFAS) are suggested to have immunosuppressive effects; exposure in utero and in the first years of life is of special concern as fetuses and small children are highly vulnerable to toxicant exposure. The objective of this study was to investigate the effect of pre-natal exposure to PFAS on responses to pediatric vaccines and immune-related health outcomes in children up to 3 years of age. In the prospective birth-cohort BraMat, a sub-cohort of the Norwegian Mother and Child Cohort Study (MoBa), pregnant women from Oslo and Akershus, Norway, were recruited during 2007-2008. Three annual questionnaire-based follow-ups were performed. Blood samples were collected from the mothers at the time of delivery and from the children at the age of 3 years. As a measure of pre-natal exposure to PFAS, the concentrations of perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS) were determined in maternal blood from 99 BraMat participants. Main outcome measures were anti-vaccine antibody levels, common infectious diseases and allergy- and asthma-related health outcomes in the children up to the age of 3 years. There was an inverse association between the level of anti-rubella antibodies in the children's serum at age 3 years and the concentrations of the four PFAS. Furthermore, there was a positive association between the maternal concentrations of PFOA and PFNA and the number of episodes of common cold for the children, and between PFOA and PFHxS and the number of episodes of gastroenteritis. No associations were found between maternal PFAS concentrations and the allergy- and asthma-related health outcomes investigated. The results indicate that pre-natal exposure to PFAS may be associated with immunosuppression in early childhood. PMID:23350954

Granum, Berit; Haug, Line S; Namork, Ellen; Stølevik, Solvor B; Thomsen, Cathrine; Aaberge, Ingeborg S; van Loveren, Henk; Løvik, Martinus; Nygaard, Unni C

2013-01-01

150

Chemical conjugation of DeltaF508-CFTR corrector deoxyspergualin to transporter human serum albumin enhances its ability to rescue Cl- channel functions.  

PubMed

The most common mutation of the cystic fibrosis (CF) gene, the deletion of Phe508, encodes a protein (DeltaF508-CFTR) that fails to fold properly, thus mutated DeltaF508-cystic fibrosis transmembrane conductance regulator (CFTR) is recognized and degraded via the ubiquitin-proteasome endoplasmic reticulum-associated degradation pathway. Chemical and pharmacological chaperones and ligand-induced transport open options for designing specific drugs to control protein (mis)folding or transport. A class of compounds that has been proposed as having potential utility in DeltaF508-CFTR is that which targets the molecular chaperone and proteasome systems. In this study, we have selected deoxyspergualin (DSG) as a reference molecule for this class of compounds and for ease of cross-linking to human serum albumin (HSA) as a protein transporter. Chemical cross-linking of DSG to HSA via a disulfide-based cross-linker and its administration to cells carrying DeltaF508-CFTR resulted in a greater enhancement of DeltaF508-CFTR function than when free DSG was used. Function of the selenium-dependent oxidoreductase system was required to allow intracellular activation of HSA-DSG conjugates. The principle that carrier proteins can deliver pharmacological chaperones to cells leading to correction of defective CFTR functions is therefore proven and warrants further investigations. PMID:18515409

Norez, Caroline; Pasetto, Matteo; Dechecchi, Maria Cristina; Barison, Erika; Anselmi, Cristina; Tamanini, Anna; Quiri, Federica; Cattel, Luigi; Rizzotti, Paolo; Dosio, Franco; Cabrini, Giulio; Colombatti, Marco

2008-08-01

151

Alternative Eluent Composition for LC-MS Analysis of Perfluoroalkyl Acids in Raw Fish Samples.  

PubMed

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

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

2014-06-11

152

Effects of perfluoroalkyl acids on the function of the thyroid hormone and the aryl hydrocarbon receptor.  

PubMed

Perfluoroalkyl acids (PFAAs) are perfluorinated compounds that widely exist in the environment and can elicit adverse effects including endocrine disruption in humans and animals. This study investigated the effect of seven PFAAs on the thyroid hormone (TH) system assessing the proliferation of the 3,3',5-triiodo-L-thryonine (T3)-dependent rat pituitary GH3 cells using the T-screen assay and the effect on the aryl hydrocarbon receptor (AhR) transactivation in the AhR-luciferase reporter gene bioassay. A dose-dependent impact on GH3 cells was observed in the range 1×10(-9)-1×10(-4) M: seven PFAAs (perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnA), and perfluorododecanoic acid (PFDoA)) inhibited the GH3 cell growth, and four PFAAs (PFOS, PFHxS, PFNA, and PFUnA) antagonized the T3-induced GH3 cell proliferation. At the highest test concentration, PFHxS showed a further increase of the T3-induced GH3 growth. Among the seven tested PFAAs, only PFDoA and PFDA elicited an activating effect on the AhR. In conclusion, PFAAs possess in vitro endocrine-disrupting potential by interfering with TH and AhR functions, which need to be taken into consideration when assessing the impact on human health. PMID:23539207

Long, Manhai; Ghisari, Mandana; Bonefeld-Jørgensen, Eva Cecilie

2013-11-01

153

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

NASA Technical Reports Server (NTRS)

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

Cobb, Stephen H.

1991-01-01

154

Sorption of short- and long-chain perfluoroalkyl surfactants on sewage sludges.  

PubMed

Perfluoroalkyl surfactants (PASs) have attracted increasing concerns in recent years due to their global distribution, persistence, bioaccumulation and potential toxicity. Since sludge was a significant source of PASs to environment, the sorption of short (C2-C6) and long-chain (C7-C15) PASs on different sewage sludge was investigated in this study. The equilibrium data were well represented by the Freundlich isotherm and were generally nonlinear. In order to elucidate the sorption mechanism of PASs to sludge, effect of sludge property, solution chemistry and molecular structure were also investigated in details. The dominant sludge parameter influencing sorption of PASs was protein in extracellular polymeric substances. The sorption of PASs onto sludge increased as solution pH decreased. For all the PASs homologues, enhanced adsorption occurred with increasing calcium concentration in solution. For PASs with C5-C15, sorption on sludge increases with increasing alkyl chain length, while for PASs with C2-C5, the association of sludge decreases when the alkyl chain length increases. The perfluorinated sulfonic acid (PFSA) demonstrated substantially stronger sorption than perfluorinated carboxylic acid (PFCA) analog. Evidence for both hydrophobic and electrostatic interactions was found. PMID:23834900

Zhang, Chaojie; Yan, Hong; Li, Fei; Hu, Xiang; Zhou, Qi

2013-09-15

155

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

PubMed

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

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

2013-07-01

156

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.; Qian Wu; Kannan, Kurunthachalam; Trowbridge, Annette; McKann, Patrick C.

2013-01-01

157

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

158

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

PubMed

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

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

2012-06-01

159

Input characterization of perfluoroalkyl substances in wastewater treatment plants: source discrimination by exploratory data analysis.  

PubMed

This paper presents a methodology based on multivariate data analysis for identifying input sources of perfluoroalkyl substances (PFASs) detected in 37 wastewater treatment plants (WWTPs) across more than 40 cities in the state of Minnesota (USA). Exploratory analysis of data points has been carried out by unsupervised pattern recognition (cluster analysis), correlation analysis, ANOVA and per capita discharges in an attempt to discriminate sources of PFASs in WWTPs. Robust cluster solutions grouped the database according to the different PFAS profiles in WWTP influent. Significantly elevated levels of perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA) and/or perfluorooctane sulfonate (PFOS) in influent have been found in 18 out of 37 WWTPs (49%). A substantial increase in the concentrations of PFHxA and/or PFOA from influent to effluent was observed in 59% of the WWTPs surveyed, suggestive of high concentration inputs of precursors. The fate of one precursor (8:2 fluorotelomer alcohol) in WWTP was modeled based on fugacity analysis to understand the increasing effluent concentration. Furthermore, population-related emissions cannot wholly explain the occurrence and levels of PFASs in WWTPs. Unusually high influent levels of PFASs were observed in WWTPs located in specific industrial areas or where known contamination had taken place. Despite the restriction on the production/use of PFOA and PFOS, this paper demonstrates that wastewater from industrial activities is still a principal determinant of PFAS pollution in urban watersheds. PMID:22483712

Xiao, Feng; Halbach, Thomas R; Simcik, Matt F; Gulliver, John S

2012-06-01

160

Acids and alkali resistant sticky superhydrophobic surfaces by one-pot electropolymerization of perfluoroalkyl alkyl pyrrole.  

PubMed

Over the past few years, electropolymerization of semifluorinated monomers like thiophene or pyrrole has been used as a gentle and effective method to generate, in one step, stable superhydrophobic surfaces. The synthetic route mostly involves the coupling reaction between a carboxylic acid and an alcohol, using a carboxy group-activated reagent and a catalyst. As a consequence, the electroformed surfaces present high liquid repellency due to the concomitant effect of roughness and low surface energy. Nevertheless, the ester connector can be cleaved under acidic and basic conditions, preventing its use under a range of environmental conditions. To overcome this drawback, a new perfluoroalkyl alkyl pyrrole has been synthesized, the fluorinated segment being connected to the electropolymerizable part via an alkyl chain, and electropolymerized, leading to surfaces that exhibit a static contact angle with water superior to 150 degrees and no sliding angle, over a wide pH range and with a long lifetime. This represents the first example of a pure conducting polymer surface with sticky superhydrophobicity not only in pure water but also in corrosive solutions such as acids and bases, giving rise to new prospects in practical applications. PMID:20060984

Nicolas, Mael

2010-03-15

161

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

PubMed

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

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

2014-06-01

162

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

PubMed

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

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

2013-03-01

163

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

EPA Science Inventory

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

164

Serendipity in perfluorinated series: unexpected synthesis of 7-(perfluoroalkyl)-2,3-dihydro-5 H-1,4-dioxepin-5-one  

Microsoft Academic Search

Treatment of [2-(perfluoroalkyl)-1,3-dioxolan-2-yl]acetic acids with thionyl chloride and a 48% HBr solution yields 7-polyfluoroalkyl-2,3-dihydro-5H-1,4-dioxepine-5-one. The production of this unexpected entity is explained by a rearrangement mechanism proposed in this work.

Barbara Villaume; Christine Gérardin-Charbonnier; Sylvie Thiébaut; Claude Selve

2001-01-01

165

Activation of Mouse and Human Peroxisome Proliferator-Activated Receptor Alpha by Perfluoroalkyl Acids of Different Functional Groups and Chain Lengths  

Microsoft Academic Search

Perfluoroalkyl acids (PFAAs) are surfactants used in consumer products and persist in the environment. Some PFAAs elicit adverse effects on rodent development and survival. PFAAs can activate peroxisome proliferator2activated receptor alpha (PPARa )a nd may act via PPARa to produce some of their effects. This study evaluated the ability of numerous PFAAs to induce mouse and human PPARa activity in

Cynthia J. Wolf; Margy L. Takacs; Judith E. Schmid; Christopher Lau; Barbara D. Abbott

2008-01-01

166

Correlation of endocrine disrupting chemicals serum levels and white blood cells gene expression of nuclear receptors in a population of infertile women.  

PubMed

Significant evidence supports that many endocrine disrupting chemicals could affect female reproductive health. Aim of this study was to compare the internal exposure to bisphenol A (BPA), perfluorooctane sulphonate (PFOS), perfluorooctanoic acid (PFOA), monoethylhexyl phthalate (MEHP), and di(2-ethylhexyl) phthalate (DEHP) in serum samples of 111 infertile women and 44 fertile women. Levels of gene expression of nuclear receptors (ER ? , ER ? , AR, AhR, PXR, and PPAR ? ) were also analyzed as biomarkers of effective dose. The percentage of women with BPA concentrations above the limit of detection was significantly higher in infertile women than in controls. No statistically significant difference was found with regard to PFOS, PFOA, MEHP and DEHP. Infertile patients showed gene expression levels of ER ? , ER ? , AR, and PXR significantly higher than controls. In infertile women, a positive association was found between BPA and MEHP levels and ER ? , ER ? , AR, AhR, and PXR expression. PFOS concentration positively correlated with AR and PXR expression. PFOA levels negatively correlated with AhR expression. No correlation was found between DEHP levels and all evaluated nuclear receptors. This study underlines the need to provide special attention to substances that are still widely present in the environment and to integrate exposure measurements with relevant indicators of biological effects. PMID:23710174

Caserta, Donatella; Ciardo, Francesca; Bordi, Giulia; Guerranti, Cristiana; Fanello, Emiliano; Perra, Guido; Borghini, Francesca; La Rocca, Cinzia; Tait, Sabrina; Bergamasco, Bruno; Stecca, Laura; Marci, Roberto; Lo Monte, Giuseppe; Soave, Ilaria; Focardi, Silvano; Mantovani, Alberto; Moscarini, Massimo

2013-01-01

167

Identification of drug-binding sites on human serum albumin using affinity capillary electrophoresis and chemically modified proteins as buffer additives.  

PubMed

A technique based on affinity capillary electrophoresis (ACE) and chemically modified proteins was used to screen the binding sites of various drugs on human serum albumin (HSA). This involved using HSA as a buffer additive, following the site-selective modification of this protein at two residues (tryptophan 214 or tyrosine 411) located in its major binding regions. The migration times of four compounds (warfarin, ibuprofen, suprofen and flurbiprofen) were measured in the presence of normal or modified HSA. These times were then compared and the mobility shifts observed with the modified proteins were used to identify the binding regions of each injected solute on HSA. Items considered in optimizing this assay included the concentration of protein placed into the running buffer, the reagents used to modify HSA, and the use of dextran as a secondary additive to adjust protein mobility. The results of this method showed good agreement with those of previous reports. The advantages and disadvantages of this approach are examined, as well as its possible extension to other solutes. PMID:11920883

Kim, Hee Seung; Austin, John; Hage, David S

2002-03-01

168

Correlation of Endocrine Disrupting Chemicals Serum Levels and White Blood Cells Gene Expression of Nuclear Receptors in a Population of Infertile Women  

PubMed Central

Significant evidence supports that many endocrine disrupting chemicals could affect female reproductive health. Aim of this study was to compare the internal exposure to bisphenol A (BPA), perfluorooctane sulphonate (PFOS), perfluorooctanoic acid (PFOA), monoethylhexyl phthalate (MEHP), and di(2-ethylhexyl) phthalate (DEHP) in serum samples of 111 infertile women and 44 fertile women. Levels of gene expression of nuclear receptors (ER?, ER?, AR, AhR, PXR, and PPAR?) were also analyzed as biomarkers of effective dose. The percentage of women with BPA concentrations above the limit of detection was significantly higher in infertile women than in controls. No statistically significant difference was found with regard to PFOS, PFOA, MEHP and DEHP. Infertile patients showed gene expression levels of ER?, ER?, AR, and PXR significantly higher than controls. In infertile women, a positive association was found between BPA and MEHP levels and ER?, ER?, AR, AhR, and PXR expression. PFOS concentration positively correlated with AR and PXR expression. PFOA levels negatively correlated with AhR expression. No correlation was found between DEHP levels and all evaluated nuclear receptors. This study underlines the need to provide special attention to substances that are still widely present in the environment and to integrate exposure measurements with relevant indicators of biological effects.

Caserta, Donatella; Ciardo, Francesca; Bordi, Giulia; Guerranti, Cristiana; Fanello, Emiliano; Perra, Guido; Borghini, Francesca; La Rocca, Cinzia; Tait, Sabrina; Bergamasco, Bruno; Stecca, Laura; Marci, Roberto; Lo Monte, Giuseppe; Soave, Ilaria; Focardi, Silvano; Mantovani, Alberto; Moscarini, Massimo

2013-01-01

169

Spatiotemporal distribution and mass loadings of perfluoroalkyl substances in the Yangtze River of China.  

PubMed

A systematic investigation into contamination profiles of eighteen perfluoroalkyl substances (PFASs) in both surface water and sediments of Yangtze River was carried out by using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) in summer and winter of 2013. The total concentrations of the PFASs in the water and sediment of Yangtze River ranged from 2.2 to 74.56ng/L and 0.05 to 1.44ng/g dry weights (dw), respectively. The PFAS concentrations were correlated to some selected water quality parameters such as pH, total phosphorus (TP), total nitrogen (TN) and conductivity in water, and some sediment properties, such as total organic carbon (TOC), TP, and TN in sediment. The monitoring results for the water and sediment samples showed no obvious seasonal variations. Among the selected 18 PFASs, perfluorooctanoic acid (PFOA) was the dominant PFAS compound found both in water and sediment for the two seasons with its maximum concentration of 18.03ng/L in water and 0.72ng/g in sediment, followed by perfluorobutane sulfonic acid (PFBS) with its maximum concentration of 41.9ng/L in water in Wuhan, whereas the lowest concentrations of PFASs were observed at Poyang lake. The annual loadings of PFOA, perfluorohexanoic acid (PFHxA), PFBS, perfluorooctane sulfonic acid (PFOS) and the total PFASs in the Yangtze River were 6.8tons, 2.2tons, 8.2tons, 0.88tons, and 20.7tons, respectively. Wuhan and Er'zhou of Hubei contributed the most amounts of PFASs into the Yangtze River. A correlation was found between some PFASs, for example PFBS and PFOS, which suggests that both of these PFASs originate from common sources in the region. PMID:24982023

Pan, Chang-Gui; Ying, Guang-Guo; Zhao, Jian-Liang; Liu, You-Sheng; Jiang, Yu-Xia; Zhang, Qian-Qian

2014-09-15

170

Spatial trends of perfluoroalkyl compounds in ringed seals (Phoca hispida) from the Canadian Arctic.  

PubMed

The present study examined spatial trends of perfluoroalkyl compounds (PFCs) in liver samples from 11 populations of ringed seals (Phoca hispida) in the Canadian Arctic from 2002 to 2005. Trophic position and relative carbon sources were compared by analyzing stable nitrogen and carbon isotopes in muscle samples. Geometric mean concentrations of total C9-C15 perfluorinated carboxylates (PFCAs) ranged from 8.8 to 84 ng/g wet weight, and C9-C11 PFCAs predominated. Perfluorooctane sulfonate was the dominant PFC measured, with concentrations ranging from 6.5 to 89 ng/g wet weight, contributing between 29 and 56% of the total PFC concentration. Overall, mean PFC concentrations were similar between populations, and differences were attributed largely to elevated levels in the Gjoa Haven (Rae Strait, central Canadian Arctic archipelago) and Inukjuak populations (eastern Hudson Bay) and to lower concentrations at Pangnirtung (Cumberland Sound, Baffin Island). Mean stable nitrogen isotope ratios (+/-95% confidence intervals) ranged from 14.7 per thousand (+/-0.3 per thousand) at Nain (Labrador) to 17.9 per thousand (+/-0.7 per thousand) at Gjoa Haven, suggesting that all populations were within the same trophic level. Stable carbon isotope ratios varied widely between the seal populations, ranging from -22.9 per thousand (+/-0.2 per thousand) at Gjoa Haven to -17.7 per thousand (+/-0.4 per thousand) at Nain. The delta13C ratios from Gjoa Haven were significantly more depleted than those for other populations and may suggest a terrestrially based carbon source. The depleted stable carbon isotope ratio may explain the elevated PFC concentrations in the Gjoa Haven population. Analysis of covariance indicated that delta13C was a significant covariable for seven of nine seal populations for which delta13C values were available. After adjusting for delta13C values, concentrations of most PFCs generally were statistically greater in the Grise Fiord, Qikiqtarjuaq, Arviat, and Nain populations. PMID:17988182

Butt, Craig M; Mabury, Scott A; Kwan, Michael; Wang, Xiaowa; Muir, Derek C G

2008-03-01

171

Biomagnification and tissue distribution of perfluoroalkyl substances (PFASs) in market-size rainbow trout (Oncorhynchus mykiss).  

PubMed

The present study investigated the biomagnification potential as well as the substance and tissue-specific distribution of perfluoroalkyl substances (PFASs) in market-size rainbow trout (Oncorhynchus mykiss). Rainbow trout with an average body weight of 314?±?21?g were exposed to perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) in the diet for 28 d. The accumulation phase was followed by a 28-d depuration phase, in which the test animals were fed with nonspiked trout feed. On days 0, 7, 14, 28, 31, 35, 42, and 56 of the present study, fish were sampled from the test basin for PFAS analysis. Biomagnification factors (BMFs) for all test compounds were determined based on a kinetic approach. Distribution factors were calculated for each test compound to illustrate the disposition of PFASs in rainbow trout after 28 d of exposure. Dietary exposure of market-size rainbow trout to PFASs did not result in biomagnification; BMF values were calculated as 0.42 for PFOS, >0.23 for PFNA, >0.18 for PFHxS, >0.04 for PFOA, and >0.02 for PFBS, which are below the biomagnification threshold of 1. Liver, blood, kidney, and skin were identified as the main target tissues for PFASs in market-size rainbow trout. Evidence was shown that despite relative low PFAS contamination, the edible parts of the fish (the fillet and skin) can significantly contribute to the whole-body burden. PMID:23686590

Goeritz, Ina; Falk, Sandy; Stahl, Thorsten; Schäfers, Christoph; Schlechtriem, Christian

2013-09-01

172

Association between thyroid profile and perfluoroalkyl acids: data from NHNAES 2007-2008.  

PubMed

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. PMID:24053974

Jain, Ram B

2013-10-01

173

Bioaccumulation of perfluoroalkyl substances by Daphnia magna in water with different types and concentrations of protein.  

PubMed

Perfluoroalkyl substances (PFASs) are sometimes regarded as proteinophilic compounds, however, there is no research report about the effect of environmental protein on the bioaccumulation of PFASs in waters. In the present study we investigated influences of protein on the bioaccumulation of six kinds of PFASs by Daphnia magna in water; it included perfluorooctane sulfonate, perfluorooctanoic acid, perfluorononanoic acid, perfluorodecanoic acid, perfluoroundecanoic acid, and perfluorododecanoic acid. Two types of protein including bovine albumin from animal and soy peptone from plant were compared and the effects of protein concentration were investigated. Both types of protein at high concentrations (10 and 20 mg L(-1)) suppressed the bioaccumulation of PFASs. When protein concentration increased from 0 to 20 mg L(-1), the decreasing ratios of the PFAS body burden (35.3-52.9%) in Daphnia magna induced by bovine albumin were significantly higher than those (22.0-36.6%) by soy peptone. The dialysis bag experiment results showed that the binding of PFASs to protein followed the Freundlich isotherm, suggesting it is not a linear partitioning process but an adsorption-like process. The partition coefficients of PFASs between bovine albumin and water were higher compared to soy peptone; this resulted in higher reducing rates of freely dissolved concentrations of PFASs with increasing bovine albumin concentration, leading to a stronger suppression of PFAS bioaccumulation. However, the presence of both types of protein with a low concentration (1 mg L(-1)) enhanced the bioaccumulation of PFASs. Furthermore, the water-based bioaccumulation factor based on the freely dissolved concentrations of PFASs even increased with and the depuration rate constants of PFASs from Daphnia magna decreased with protein concentration, suggesting that protein would not only reduce the bioavailable concentrations and uptake rates of PFASs but also lower the elimination rates of PFASs in Daphnia magna. Because these two opposite effects would change with different protein concentrations in water, the net effect of protein on PFAS bioaccumulation would also vary with protein concentration. PMID:23968486

Xia, Xinghui; Rabearisoa, Andry H; Jiang, Xiaoman; Dai, Zhineng

2013-10-01

174

Occurrence of perfluoroalkyl surfactants in water, fish, and birds from New York State.  

PubMed

Concentrations of perfluorooctanesulfonate (PFOS) and several other perfluoroalkyl surfactants (PASs) were determined in nine 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 waterfowl (n = 87) from the Niagara River region in NYS. PFOS, perfluorooctanoic acid (PFOA), and perfluorohexanesulfonate (PFHS) were ubiquitous in NYS waters. PFOA was typically found at higher concentrations than were PFOS and PFHS. Elevated concentrations of PFOS were found in surface waters of Lake Onondaga, and elevated concentrations of PFOA were found in the Hudson River. PFOS was the most abundant perfluorinated compound in all fish and bird samples. PFOS concentrations in the livers of fishes ranged from 9 to 315 ng/g wet weight. PFOS, PFOA, and PFOSA (perfluorooctanesulfonamide) concentrations in smallmouth and largemouth bass (taken together) caught in remote mountain lakes with no known point sources of PAS contamination were 14 to 207, < 1.5 to 6.1, and < 1.5 to 9.8 ng/g wet weight, respectively. PFOS concentrations in the livers of birds ranged from 11 to 882 ng/g wet weight. PFOS concentrations were 2.5-fold greater (p = 0.001) in piscivorous birds than in non-piscivorous birds. However, PFOA, PFOSA, and PFHS were not found in bird livers. Overall, average concentrations of PFOS in fish were 8850-fold greater than those in surface water. An average biomagnification factor of 8.9 was estimated for PFOS in common merganser relative to that in fish. This study highlights the significance of dietary fish in PFOS accumulation in the food chain. Furthermore, our results provide information on the distribution of PASs in natural waters, fish, and several bird species in NYS. PMID:16435086

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

2006-04-01

175

Analysis of perfluoroalkyl substances in cord blood by turbulent flow chromatography coupled to tandem mass spectrometry.  

PubMed

A fast on-line analytical method based on turbulent flow chromatography (TFC) in combination with tandem mass spectrometry has been applied for the first time for the analysis of eighteen perfluoroalkyl substances (PFASs), in cord blood. A simple and rapid sample pre-treatment was optimised consisting on protein precipitation of 100 ?L of sample with acetonitrile (1:1) followed by centrifugation during 10 min. The method was adapted to be sensitive enough and robust with minimum sample injection volume requirements (20 ?L). The optimised methodology presented method limits of detection (MLOD) between 0.031 and 0.76 ?g/L, detection capabilities (CC?) in the range between 0.005 and 0.99 ?g/L and decision limits (CC?) ranging from 0.006 to 1.16 ?g/L. The recoveries in blank blood were calculated by spiking experiments with a mixture of 18 PFASs and established between 70 and 126% for most of compounds. Isotopic dilution was carried out for quantification of selected analytes. In-house validation of this new approach was carried out according to the requirements in the 2002/657/EC Decision. Finally the good applicability of this new approach was proved by the analysis of 60 cord blood samples from two different Mediterranean cities, Barcelona (Spain) and Heraklion (Greece). Ions perfluorohexanesulfonate (PFHxS) and perfluorooctanesulfonate (PFOS) were found at highest concentration and the more frequently compounds were PFHxS, PFOS and perfluorooctanoic acid (PFOA). The newly developed method proved to be suitable for large-scale epidemiologic studies, and to the data on PFASs exposure during pregnancy. PMID:22789815

Llorca, Marta; Pérez, Francisca; Farré, Marinella; Agramunt, Sílvia; Kogevinas, Manolis; Barceló, Damià

2012-09-01

176

Short communication: Monitoring the presence of perfluoroalkyl substances in Italian cow milk.  

PubMed

Perfluoroalkyl substances (PFAS) are fully fluorinated compounds widely used during the last 60 yr in the production of multiple industrial and consumer applications, such as food packaging, nonstick cookware, cleaning agents, and many more. These emerging contaminants have recently become of concern for human health because of their potential negative effects. The risk of exposure to PFAS for humans is mainly related to diet, and the increasing interest in food safety has led the European Commission to call Member States to monitor these contaminants in food matrices. The purpose of the present work was to perform the first monitoring on the presence of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), the 2 main and most widely investigated molecules of this family, in cow milk commercially available in Italy. We used an analytical protocol consisting of liquid-liquid extraction followed by 2 purification steps through solid-phase extraction cartridges and injection on an ultra-performance liquid chromatography-tandem mass spectroscopy system. The analysis of 67 samples of different types of cow milk from Italy demonstrated that contamination by PFOS was often present, although at relatively low concentrations (up to 97ng/L), whereas PFOA was rarely found. On the basis of these results and data reported in the literature on this matrix, milk does not seem to be a major source of PFAS compared with other food categories such as fish and seafood. However, variability among different types of milk must be taken into account, and surveys of milk-derived products would be helpful to better define the risk for consumers. PMID:24704228

Barbarossa, Andrea; Gazzotti, Teresa; Zironi, Elisa; Serraino, Andrea; Pagliuca, Giampiero

2014-06-01

177

pKa, zinc- and serum albumin-binding of curcumin and two novel biologically-active chemically-modified curcumins.  

PubMed

The pH equilibria and the zinc ion and bovine serum albumin (BSA) binding behavior of curcumin and two chemically modified curcumins (CMCs), namely 4-methoxycarbonylcurcumin (CMC 2.5) and 4-phenylaminocarbonyl bis-demethoxy curcumin (CMC 2.24), were studied, in order to understand the basis of their differential effects on the zinc-enzyme matrix metalloproteinases (MMPs) as well as the effect of charge state on their behavior in vivo. Moreover, all three compounds transform rapidly in the pH range 5-10, CMC 2.5 largely in one step, and CMC 2.24 and curcumin first in a rapid process to an intermediate form that still displays an enolic and two phenolic hydrogen-ion equilibria, and then more slowly to forms absorbing primarily in the lower UV and lacking the strong absorbance in the visible characteristic of the enol-centered chromophore. The binding of these compounds in one of the hydrophobic pockets of the major transport protein, serum albumin, was therefore studied. CMC 2.24 binds more strongly to BSA than curcumin, with a dissociation constant of 0.56±0.08 ?M compared to 1.32±0.17 ?M. Binding to BSA shifts the decomposition half-lives from tens of seconds to tens of hours. The zero-time acid dissociation constants (pK(a)) for species H(3)D, H(2)D(-), and HD(2-) are 8.41, 9.94 and 11.2; 6.98, 8.40 and 9.8; and 6.50 and 8.82 ; for curcumin, CMC 2.24, and CMC 2.5 respectively (there is no distinguishable pK(a3) for CMC 2.5). Zn(2+) binds most strongly to CMC 2.24 compared to CMC 2.5 and curcumin, with dissociation constants of 0.77±0.02, 1.88±0.07, and 1.39±0.09 mM. The increased acidity and Zn(2+) and BSA affinities of CMC 2.24 correlate with its greater biological activity. PMID:22830351

Zhang, Yu; Golub, Lorne M; Johnson, Francis; Wishnia, Arnold

2012-01-01

178

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

PubMed

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

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

2013-02-01

179

Surface chemical approach to single-step measurement of antibody in human serum using localized surface plasmon resonance biosensor on microtiter plate system.  

PubMed

In clinical settings, serum antibody levels serve as markers of pathology. For example, antibodies related to autoimmune diseases are among the conventional targets in laboratory tests. Simple clinical tests can improve the efficacy of laboratory practice. This study describes a single-step, wash-free technique for optically detecting antibodies in human serum through the localized surface plasmon resonance (LSPR) of gold nanoparticles. As a proof-of-concept experiment, the amount of antibiotin dissolved in human serum was measured with a LSPR-based biosensor in a wash-free manner using a conventional 96-well microtiter plate and a plate reader. For an efficient surface modification of biosensors, zwitterionic copolymer was used as a scaffold on the gold nanoparticle surface to immobilize antigen and blocking reagent. Single-step, wash-free measurement of antibiotin in human serum was successfully achieved. In addition, nonspecific responses from serum contents were significantly reduced because both the copolymer and hydrophilic antigen reagent that we employed were composed of poly(ethylene oxide) spacer. Comparative experiments of the antigen-antibody reaction in serum to that in buffered solution revealed that serum is a favorable environment for the biological reaction. In conclusion, our gold-nanoparticle-based LSPR method may provide a rapid and simple way to measure the amount of antibody in serum quantitatively in clinical practice. PMID:24770806

Yamamichi, Junta; Ojima, Tetsunori; Iida, Mie; Yurugi, Kimiko; Imamura, Takeshi; Ashihara, Eishi; Kimura, Shinya; Maekawa, Taira

2014-07-01

180

Site-specific chemical modification of human serum albumin with polyethylene glycol prolongs half-life and improves intravascular retention in mice.  

PubMed

Human serum albumin (HSA) is used as an important plasma volume expander in clinical practice. However, the infused HSA may extravasate into the interstitial space and induce peripheral edema in treating the critical illness related to marked increase in capillary permeability. Such poor intravascular retention also demands a frequent administration of HSA. We hypothesize that increasing the molecular weight of HSA by PEGylation may be a potential approach to decrease capillary permeability of HSA. In the present study, HSA was PEGylated in a site-specific manner and the PEGylated HSA carrying one chain of polyethylene glycol (PEG) (20 kDa) per HSA molecule was obtained. The purity, PEGylated site and secondary structure of the modified protein were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), thiol group blockage method and circular dichroism (CD) measurement, respectively. In addition, the pharmacokinetics in normal mice was investigated, vascular permeability of the PEGylated HSA was evaluated in lipopolysaccharide (LPS)-induced lung injury mouse model and the pharmacodynamics was investigated in LPS-induced sepsis model with systemic capillary leakage. The results showed that the biological half-life of the modified HSA was approximately 2.3 times of that of the native HSA, PEG-HSA had a lower vascular permeability and better recovery in blood pressure and haemodilution was observed in rats treated with PEG-HSA. From the results it can be inferred that the chemically well-defined and molecularly homogeneous PEGylated HSA is superior to HSA in treating capillary permeability increase related illness because of its longer biological half-life and lower vascular permeability. PMID:22382312

Zhao, Ting; Cheng, Yan-Na; Tan, Hai-Ning; Liu, Jin-Feng; Xu, Huan-Li; Pang, Guang-Li; Wang, Feng-Shan

2012-01-01

181

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

182

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

183

Determinants of plasma concentrations of perfluoroalkyl substances in pregnant Norwegian women  

PubMed Central

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

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

2013-01-01

184

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

PubMed

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

Guelfo, Jennifer L; Higgins, Christopher P

2013-05-01

185

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

PubMed

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

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

2013-11-01

186

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

187

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

188

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

189

Ombrotrophic peat bogs are not suited as natural archives to investigate the historical atmospheric deposition of perfluoroalkyl substances.  

PubMed

As ombrotrophic peat bogs receive only atmospheric input of contaminants, they have been identified as suitable natural archives for investigating historical depositions of airborne pollutants. To elucidate their suitability for determining the historical atmospheric contamination with perfluoroalkyl substances (PFAS), two peat cores were sampled at Mer Bleue, a bog located close to Ottawa, Canada. Peat cores were segmented, dried, and analyzed in duplicate for 25 PFASs (5 perfluororalkyl sulfonates (PFSAs), 13 perfluoroalkyl carboxylates (PFCAs), 7 perfluororalkyl sulfonamido substances). Peat samples were extracted by ultrasonication, cleaned up using a QuEChERS method, and PFASs were measured by HPLC-MS/MS. Twelve PFCAs and PFSAs were detected regularly in peat samples with perfluorooctane sulfonate (85-655 ng kg(-1)), perfluorooctanoate (150-390 ng kg(-1)), and perfluorononanoate (45-320 ng kg(-1)) at highest concentrations. Because of post depositional relocation processes within the peat cores, true or unbiased deposition fluxes (i.e., not affected by post depositional changes) could not be calculated. Apparent or biased deposition rates (i.e., affected by post depositional changes) were lower than measured/calculated deposition rates for similar urban or near-urban sites. Compared to PFAS production, PFAS concentration and deposition maxima were shifted about 30 years toward the past and some analytes were detected even in the oldest segments from the beginning of the 20th century. This was attributed to PFAS mobility in the peat profile. Considerable differences were observed between both peat cores and different PFASs. Overall, this study demonstrates that ombrotrophic bogs are not suited natural archives to provide authentic and reliable temporal trend data of historical atmospheric PFAS deposition. PMID:22680699

Dreyer, Annekatrin; Thuens, Sabine; Kirchgeorg, Torben; Radke, Michael

2012-07-17

190

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

191

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

Microsoft Academic Search

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

Sierra Rayne; Kaya Forest

2009-01-01

192

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

193

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 ...

194

Isolation and structural X-ray investigation of perfluoroalkyl derivatives of six cage isomers of C84.  

PubMed

Perfluoroalkylation of a higher fullerene mixture with CF(3)I or C(2)F(5)I, followed by HPLC separation of CF(3) and C(2)F(5) derivatives, resulted in the isolation of several C(84)(R(F))(n) (n=12, 16) compounds. Single-crystal X-ray crystallography with the use of synchrotron radiation allowed structure elucidation of eight C(84)(R(F))(n) compounds containing six different C(84) cages (the number of the C(84) isomer is given in parentheses): C(84) (23)(C(2)F(5))(12) (I), C(84) (22)(CF(3))(16) (II), C(84) (22)(C(2)F(5))(12) (III), C(84) (11)(C(2)F(5))(12) (IV), C(84) (16)(C(2)F(5))(12) (V), C(84) (4)(CF(3))(12) (VI with toluene and VII with hexane as solvate molecules), and C(84) (18)(C(2)F(5))(12) (VIII). Whereas some connectivity patterns of C(84) isomers (22, 23, 11) had previously been unambiguously confirmed by different methods, derivatives of C(84) isomers numbers 4, 16, and 18 have been investigated crystallographically for the first time, thus providing direct proof of the connectivity patterns of rare C(84) isomers. General aspects of the addition of R(F) groups to C(84) cages are discussed in terms of the preferred positions in the pentagons under the formation of chains, pairs, and isolated R(F) groups. PMID:19739224

Tamm, Nadezhda B; Sidorov, Lev N; Kemnitz, Erhard; Troyanov, Sergey I

2009-10-12

195

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.

Venkatesan, Arjun K.; Halden, Rolf U.

2013-01-01

196

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

PubMed Central

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

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

2011-01-01

197

Perfluoroalkyl substances in eggs and plasma of an avian top predator, great skua (Stercorarius skua), in the North Atlantic.  

PubMed

Temporal, biological, and environmental factors affecting accumulation of perfluoroalkyl substances (PFASs) are poorly understood in comparison with legacy lipid-soluble persistent organic pollutants. Temporal and biological comparisons of PFAS concentrations were made in great skuas (Stercorarius skua), a marine apex predator. Concentrations of 16 PFASs were quantified, including C4-C10 perfluorosulfonates (PFSAs), perfluorooctanesulfonamide (PFOSA), and C5-C14 perfluorocarboxylates (PFCAs). Concentrations of PFASs (ng/g wet wt) were significantly higher in eggs collected in Shetland in 2008 compared with 1980 for most compounds. However, the magnitude of the differences was small, with a mean increase of 3?ng/g. Levels of PFASs in great skuas were low compared with those of other seabirds in similar ecological niches; and in contrast to other contaminants measured in the same eggs, concentrations of PFASs did not correlate with trophic level. Concentrations of PFASs in adult plasma were significantly higher in males than in females for most PFASs. This suggests that maternal transfer through egg laying may be a significant mode of elimination of PFASs in female great skuas. The low concentrations of PFASs in eggs and plasma compared with other halogenated organic contaminants and other species suggest that great skuas do not bioaccumulate PFASs to the same extent as some other seabirds. PMID:23258709

Leat, Eliza H K; Bourgeon, Sophie; Eze, Jude I; Muir, Derek C G; Williamson, Mary; Bustnes, Jan O; Furness, Robert W; Borgå, Katrine

2013-03-01

198

Removal of PFOS, PFOA and other perfluoroalkyl acids at water reclamation plants in South East Queensland Australia.  

PubMed

This paper examines the fate of perfluorinated sulfonates (PFSAs) and carboxylic acids (PFCAs) in two water reclamation plants in Australia. Both facilities take treated water directly from WWTPs and treat it further to produce high quality recycled water. The first plant utilizes adsorption and filtration methods alongside ozonation, whilst the second uses membrane processes and advanced oxidation to produce purified recycled water. At both facilities perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorohexanoic acid (PFHxA) and perfluorooctanoic acid (PFOA) were the most frequently detected PFCs. Concentrations of PFOS and PFOA in influent (WWTP effluent) ranged up to 3.7 and 16 ng L?¹ respectively, and were reduced to 0.7 and 12 ng L?¹ in the finished water of the ozonation plant. Throughout this facility, concentrations of most of the detected perfluoroalkyl compounds (PFCs) remained relatively unchanged with each successive treatment step. PFOS was an exception to this, with some removal following coagulation and dissolved air flotation/sand filtration (DAFF). At the second plant, influent concentrations of PFOS and PFOA ranged up to 39 and 29 ng L?¹. All PFCs present were removed from the finished water by reverse osmosis (RO) to concentrations below detection and reporting limits (0.4-1.5 ng L?¹). At both plants the observed concentrations were in the low parts per trillion range, well below provisional health based drinking water guidelines suggested for PFOS and PFOA. PMID:21051071

Thompson, Jack; Eaglesham, Geoff; Reungoat, Julien; Poussade, Yvan; Bartkow, Michael; Lawrence, Michael; Mueller, Jochen F

2011-01-01

199

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

EPA Science Inventory

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

200

DISPERSION POLYMERIZATION OF POLY(METHYL METHACRYLATE) AND POLY(VINYL PYRROLIDONE) STABILIZED WITH POLY(PERFLUOROALKYL (METH)ACRYLATE) IN SUPERCRITICAL CARBON DIOXIDE  

Microsoft Academic Search

In this study, homogeneous radical polymerization of perfluoro (meth)acrylate (CH2=C(H or CH3)COO(CH2)nRf, n=1 or 2, Rf=perfluoroalkyl) using AIBN as the initiator in supercritical CO2 were carried out at T=343K, P=300-320 bar. And these fluoro-polymer were analyzed with 1H-NMR, FT-IR, GPC, etc. The resulting polymer was then used as a stabilizer for the free radical dispersion polymerization of PMMA (Poly (methyl

201

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 308K 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

202

Temporal trends of perfluoroalkyl acids in plasma samples of pregnant women in Hokkaido, Japan, 2003-2011.  

PubMed

Perfluoroalkyl acids (PFAAs) are persistent organic pollutants that are used in a wide range of consumer products. Recent epidemiological studies have shown that prenatal exposure to toxic levels of PFAAs in the environment may adversely affect fetal growth and humoral immune response in infants and children. Here we have characterized levels of prenatal exposure to PFAA between 2003 and 2011 in Hokkaido, Japan, by measuring PFAA concentrations in plasma samples from pregnant women. The study population comprised 150 women who enrolled in a prospective birth cohort study conducted in Hokkaido. Eleven PFAAs were measured in maternal plasma samples using simultaneous analysis by ultra-performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry. At the end of the study, in 2011, age- and parity-adjusted mean concentrations of perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), perfluorotridecanoic acid (PFTrDA), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS) were 1.35ng/mL, 1.26ng/mL, 0.66ng/mL, 1.29ng/mL, 0.25ng/mL, 0.33ng/mL, 0.28ng/mL, and 3.86ng/mL, respectively. Whereas PFOS and PFOA concentrations declined 8.4%/y and 3.1%/y, respectively, PFNA and PFDA levels increased 4.7%/y and 2.4%/y, respectively, between 2003 and 2011. PFUnDA, PFDoDA, and PFTrDA were detected in the vast majority of maternal samples, but no significant temporal trend was apparent. Future studies must involve a larger population of pregnant women and their children to determine the effects of prenatal exposure to PFAA on health outcomes in infants and children. PMID:24013022

Okada, Emiko; Kashino, Ikuko; Matsuura, Hideyuki; Sasaki, Seiko; Miyashita, Chihiro; Yamamoto, Jun; Ikeno, Tamiko; Ito, Yoichi M; Matsumura, Toru; Tamakoshi, Akiko; Kishi, Reiko

2013-10-01

203

Occurrence of perfluoroalkyl acids including perfluorooctane sulfonate isomers in Huai River Basin and Taihu Lake in Jiangsu Province, China.  

PubMed

The spatial distribution of 10 perfluoroalkyl acids including linear and branched (six monotrifluoromethyl isomers) perfluorooctane sulfonate (PFOS) in surface water was investigated in Huai River Basin and Taihu Lake in Jiangsu Province, China. In the water samples from Huai River Basin, perfluorooctanoic acid (PFOA) and PFOS were the predominant compounds (mean 18 ng/L and 4.7 ng/L, respectively), while in samples from Taihu Lake, PFOA, perfluorohexanoic acid (PFHxA), and PFOS were the predominant compounds (mean 56 ng/L, 19 ng/L, and 15 ng/L, respectively). Branched PFOS (Br-PFOS) isomers accounting for 48.1% to 62.5% of total PFOS were enriched in all samples from Taihu Lake, compared to technical electrochemical fluorination (ECF) PFOS (Br-PFOS ?30.0%), while the similar phenomena were not found in samples from Huai River Basin (Br-PFOS 29.0-35.0%). Principal component analysis (PCA) on the percentages of the individual isomer showed that the first two components accounted for 78.4% and 15.3% of the overall observed data variance. Samples from Huai River Basin were grouped together with the ECF PFOS standard suggesting the profiles were similar, while samples from Taihu Lake were grouped by themselves, suggesting that isomer profiles in these samples were different from that of Huai River Basin. The obvious difference in isomer profiles probably results from the different environmental behaviors of PFOS isomers and/or unknown sources (PFOS or PFOS precursors). PMID:23253185

Yu, Nanyang; Shi, Wei; Zhang, Beibei; Su, Guanyong; Feng, Jianfang; Zhang, Xiaowei; Wei, Si; Yu, Hongxia

2013-01-15

204

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...

205

Temporal trends of perfluoroalkyl contaminants in polar bears (Ursus maritimus) from two locations in the North American Arctic, 1972-2002.  

PubMed

Perfluoroalkyl substances are globally distributed anthropogenic contaminants. Their production and use have increased dramatically from the early 1980s. While many recent publications have reported concentrations of perfluorooctane sulfonate (PFOS) and other perfluoroalkyl acids (PFAs) in biotic and abiotic samples, only limited work has addressed temporal trends. In this study we analyzed archived polar bear(Ursus maritimus) livertissue samples from two geographic locations in the North American Arctic, collected from 1972 to 2002. The eastern group, taken from the vicinity of northern Baffin Island, Canada, comprised 31 samples, and the western group, from the vicinity of Barrow, Alaska, comprised 27 samples. Samples were analyzed for perfluorocarboxylic acids (PFCAs) from carbon chain length C8 to C15, perfluorohexane sulfonate, PFOS, the neutral precursor perfluorooctane sulfonamide (PFOSA), as well as 8:2 and 10:2 fluorotelomer acids and their alpha,beta unsaturated acid counterparts. Concentrations of PFOS and PFCAs with carbon chain lengths from C9 to C11 showed an exponential increase between 1972 and 2002 at both locations. Doubling times ranged from 3.6 +/- 0.9 years for perfluorononanoic acid in the eastern group to 13.1 +/- 4.0 years for PFOS in the western group. PFOSA showed decreasing concentrations over time at both locations, while the remaining PFAs showed no significant trends or were not detected in any sample. The doubling time for PFOS was similar to the doubling time of production of perfluoroctylsulfonyl-fluoride-based products during the 1990s. PMID:16572767

Smithwick, Marla; Norstrom, Ross J; Mabury, Scott A; Solomon, Keith; Evans, Thomas J; Stirling, Ian; Taylor, Mitch K; Muir, Derek C G

2006-02-15

206

Temporal trends of perfluoroalkyl concentrations in American Red Cross adult blood donors, 2000-2010.  

PubMed

Eleven perfluorinated alkyl acids (PFAAs) were analyzed in plasma from a total of 600 American Red Cross adult blood donors from six locations in 2010. The samples were extracted by protein precipitation and quantified by using liquid chromatography tandem mass spectrometry (HPLC/MS/MS). The anions of the three perfluorosulfonic acids measured were perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS). The anions of the eight perfluorocarboxylic acids were perfluoropentanoate (PFPeA), perfluorohexanoate (PFHxA), perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnA), and perfluorododecanoate (PFDoA). Findings were compared to results from different donor samples analyzed at the same locations collected in 2000-2001 (N = 645 serum samples) and 2006 (N = 600 plasma samples). Most measurements in 2010 were less than the lower limit of quantitation for PFBS, PFPeA, PFHxA, and PFDoA. For the remaining analytes, the geometric mean concentrations (ng/mL) in 2000-2001, 2006, and 2010 were, respectively, PFHxS: (2.25, 1.52, 1.34); PFOS (34.9, 14.5, 8.3); PFHpA (0.13, 0.09, 0.05); PFOA (4.70, 3.44, 2.44); PFNA (0.57, 0.97, 0.83); PFDA (0.16, 0.34, 0.27), and PFUnA (0.10, 0.18, 0.14). The percentage decline (parentheses) in geometric mean concentrations from 2000-2001 to 2010 were PFHxS (40%), PFOS (76%), and PFOA (48%). The decline in PFOS suggested a population halving time of 4.3 years. This estimate is comparable to the geometric mean serum elimination half-life of 4.8 years reported in individuals. This similarity supports the conclusion that the dominant PFOS-related exposures to humans in the United States were greatly mitigated during the phase-out period. PMID:22554481

Olsen, Geary W; Lange, Cleston C; Ellefson, Mark E; Mair, David C; Church, Timothy R; Goldberg, Corinne L; Herron, Ross M; Medhdizadehkashi, Zahra; Nobiletti, John B; Rios, Jorge A; Reagen, William K; Zobel, Larry R

2012-06-01

207

Concentrations of perfluoroalkyl compounds in maternal and umbilical cord sera and birth outcomes in Korea.  

PubMed

This study analyzed the concentrations of perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonate (PFHxS) in maternal and umbilical cord sera at delivery from the general population in Korea. Seventy samples were analyzed with ion-pairing and LC/MS/MS. PFOS, PFOA and PFHxS were detected in both maternal and umbilical cord sera. There was a high correlation of PFC concentrations between maternal and cord serum samples, implying transplacental transport. Ranking of transplacental transfer efficiency was PFOA>PFHxS>PFOS. Student's t-tests revealed that concentrations of maternal PFOA were related with decreases in birth weight, birth length and ponderal index, suggesting a possible impact on fetal growth. With multiple logistic regression models, maternal PFOS concentration showed a significant inverse association with ponderal index (OR=0.22; 95% CI, 0.05-0.90). Umbilical cord PFHxS concentration showed a significant inverse association with birth weight (OR=0.26; 95% CI, 0.08-0.85) or a marginally significant inverse association with birth length (OR=0.33; 95% CI, 0.09-1.17). This is the first report demonstrating an inverse association of birth outcomes with PFHxS exposure. Concentrations of maternal PFOA were decreased with parity, implying that delivery is one of the major routes for PFOA elimination in women. This study demonstrated prenatal exposure of PFCs through placental transfer which could result in possible developmental effects in the population sampled. Our results may provide data basis to conduct a larger scale investigation into developmental effects of PFCs in the future and contribute to understanding levels of PFC contaminations from a variety of populations in the globe. PMID:22990023

Lee, Youn Ju; Kim, Min-Kyun; Bae, Jisuk; Yang, Jae-Ho

2013-02-01

208

Perfluoroalkyl contaminants in Lake Ontario Lake Trout: detailed examination of current status and long-term trends.  

PubMed

Perfluoroalkyl contaminants (PFCs) were determined in Lake Ontario Lake Trout sampled annually between 1997 and 2008 in order to assess how current trends are responding to recent regulatory bans and voluntary phase-outs. We also combined our measurements with those of a previous study to provide an updated assessment of long-term trends. Concentrations of PFCs generally increased from the late 1970s until the mid-1980s to mid-1990s, after which concentrations either remained unchanged (perfluorooctane sulfonate (PFOS) and perfluorocarboxylates) or declined (perfluorodecanesulfonate (PFDS)). The temporal trends were assessed using three models, quadratic, exponential rise to maximum, and two-segment linear piecewise function, and then evaluated for best fit using Akaike Information Criteria. For PFOS and perfluorocarboxylates, the exponential rise to maximum function had the best fit. This is particularly interesting for PFOS as it suggests that although concentrations in Lake Ontario Lake Trout may have stopped increasing in response to voluntary phase-outs in 2000-2002, declines have yet to be observed. This may be due to continuing input of PFOS from products still in use and/or slow degradation of larger precursor molecules. A power analysis of PFOS suggested that 15 years of data with a within-year sample size of 10 is required to obtain sufficient power (80%) to detect a 5% decreasing trend. However, the length of the monitoring program had a greater influence on the ability to detect a trend compared to within-year sample size. This provides evidence that additional sampling years are required to detect a response to bans and phase-outs, given the variability in the fish data. The lack of observed declines of perfluorocarboxylate residues in fish may be expected as regulations for these compounds were only recently enacted. In contrast to the other compounds, the quadratic model had the best fit for PFDS. The results of this study emphasize the importance of long-term monitoring for assessing the effectiveness of bans and phase-outs on PFCs in the environment. PMID:22553902

Gewurtz, Sarah B; De Silva, Amila O; Backus, Sean M; McGoldrick, Daryl J; Keir, Michael J; Small, Jeff; Melymuk, Lisa; Muir, Derek C G

2012-06-01

209

A fast and simple procedure for determination of perfluoroalkyl substances in food and feed: a method verification by an interlaboratory study.  

PubMed

In this study, a simple, fast, and cheap sample preparation procedure for the analysis of three well-known representatives of perfluoroalkyl substances (perfluorooctane sulfonate, perfluorooctanoic acid, and perfluorooctane sulfonamide) was validated in accordance with Commission Decision 2002/657/EC. The method was based on extraction with methanol followed by a dispersive solid phase extraction cleanup step by addition of activated charcoal for fish tissue, fish feed, and milk samples. The novel analytical approach combined with liquid chromatography-tandem mass spectrometry makes it possible to achieve limits of quantification below 1 ?g/kg (defined by Commission Recommendation 2010/161/EU). This method provides a high laboratory sample throughput: ten samples in 60 min. The validated procedure was successfully verified in an interlaboratory study. PMID:23609786

Hrádková, P; Poustka, J; Pulkrabová, J; Hlousková, V; Kocourek, V; Llorca, M; Farré, M; Barceló, D; Hajslová, J

2013-09-01

210

Perfluoroalkyl substances in the blood of wild rats and mice from 47 prefectures in Japan: use of samples from nationwide specimen bank.  

PubMed

Numerous studies have reported on the global distribution, persistence, fate, and toxicity of perfluoroalkyl and polyfluoroalkyl substances (PFASs). However, studies on PFASs in terrestrial mammals are scarce. Rats can be good sentinels of human exposure to toxicants because of their habitat, which is in close proximity to humans. Furthermore, exposure data measured for rats can be directly applied for risk assessment because many toxicological studies use rodent models. In this study, a nationwide survey of PFASs in the blood of wild rats as well as surface water samples collected from rats' habitats from 47 prefectures in Japan was conducted. In addition to known PFASs, combustion ion chromatography technique was used for analysis of total fluorine concentrations in the blood of rats. In total, 216 blood samples representing three species of wild rats (house rat, Norway rats, and field mice) were analyzed for 23 PFASs. Perfluorooctanesulfonate (PFOS; concentration range <0.05-148 ng/mL), perfluorooctane sulfonamide (PFOSA; <0.1-157), perfluorododecanoate (<0.05-5.8), perfluoroundecanoate (PFUnDA; <0.05-51), perfluorodecanoate (PFDA; <0.05-9.7), perfluorononanoate (PFNA; <0.05-249), and perfluorooctanoate (PFOA) (<0.05-60) were detected >80 % of the blood samples. Concentrations of several PFASs in rat blood were similar to those reported for humans. PFSAs (mainly PFOS) accounted for 45 % of total PFASs, whereas perfluoroalkyl carboxylates (PFCAs), especially PFUnDA and PFNA, accounted for 20 and 10 % of total PFASs, respectively. In water samples, PFCAs were the predominant compounds with PFOA and PFNA found in >90 % of the samples. There were strong correlations (p < 0.001 to p < 0.05) between human population density and levels of PFOS, PFNA, PFOA, and PFOSA in wild rat blood. PMID:23494483

Taniyasu, Sachi; Senthilkumar, Kurunthachalam; Yamazaki, Eriko; Yeung, Leo W Y; Guruge, Keerthi S; Kannan, Kurunthachalam; Yamashita, Nobuyoshi

2013-07-01

211

Synthesis, structure, electronic spectroscopy, photophysics, electrochemistry, and X-ray photoelectron spectroscopy of highly-electron-deficient [5,10,15,20-tetrakis(perfluoroalkyl)porphinato]zinc(II ) complexes and their free base derivatives  

SciTech Connect

The synthesis, optical spectroscopy, photophysical properties, electrochemistry, and X-ray photoelectron spectroscopy of a series of [5,10,15,20-tetrakis(perfluoroalkyl)porphinato]zinc(II ) complexes and their free base analogs are reported. The title compounds were prepared by a condensation methodology that utilizes perfluoro-1-(2`-pyrrolyl)-1-alkanol precursors and employs continuous water removal throughout the course of the reaction to yield the meso perfluorocarbon-substituted porphyrins. The nature of the porphyrin-pendant meso-perfluoroalkyl group exerts considerable influence over the macrocycle`s solubility properties. The structure of the monopyridyl adduct of [5,10,15,20-tetrakis(heptafluoropropyl)porphinato] zinc(II) features an S{sub 4}-distorted porphyrin core; X-ray data are given. Electrochemical studies carried out on these porphyrin and (porphinato)zinc(II) complexes indicate that meso-perfluoroalkylporphyrins are among the most electron-deficient porphyrinic species known. X-ray photoelectron spectroscopy experiments corroborate the electron poor nature of these systems and evince extreme stabilization of the nitrogen ls orbitals, consonant with particularly effective removal of electron density from the macrocycle by the meso-perfluoroalkyl moieties that is modulated by {sigma}-symmetry orbitals. 27 refs., 8 figs., 6 tabs.

Goll, J.G.; Moore, K.T.; Therien, M.J. [Univ. of Pennsylvania, Philadelphia, PA (United States)] [Univ. of Pennsylvania, Philadelphia, PA (United States); Ghosh, A. [Univ., of Tromso (Norway)] [Univ., of Tromso (Norway)

1996-09-04

212

Protein electrophoresis - serum  

MedlinePLUS

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

213

SERUM CHANGES FOLLOWING THYROPARATHYROIDECTOMY  

PubMed Central

1. In thyroparathyroidectomized dogs the onset of tetany bears no constant relation to the ferment-antiferment balance of the serum. 2. The serum lipase titer remains at a low level throughout. 3. A progressive increase in non-coagulable nitrogen and proteoses is observed in the serum following the removal of the glands. 4. The amino nitrogen of the serum is usually increased at the time when tetany is most marked.

Petersen, William; Jobling, James W.; Eggstein, A. A.

1916-01-01

214

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

PubMed

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

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

2014-05-01

215

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

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

2014-01-01

216

Transactivation potencies of the Baikal seal (Pusa sibirica) peroxisome proliferator-activated receptor ? by perfluoroalkyl carboxylates and sulfonates: estimation of PFOA induction equivalency factors.  

PubMed

The present study assessed the transactivation potencies of the Baikal seal (Pusa sibirica) peroxisome proliferator-activated receptor ? (BS PPAR?) by perfluorochemicals (PFCs) having various carbon chain lengths (C4-C12) using an in vitro reporter gene assay. Among the twelve PFCs treated with a range of 7.8-250 ?M concentration, eight perfluoroalkyl carboxylates (PFCAs) and two perfluoroalkyl sulfonates (PFSAs) induced BS PPAR?-mediated transcriptional activities in a dose-dependent manner. To compare the BS PPAR? transactivation potencies of PFCs, the present study estimated the PFOA induction equivalency factors (IEFs), a ratio of the 50% effective concentration of PFOA to the concentration of each compound that can induce the response corresponding to 50% of the maximal response of PFOA. The order of IEFs for the PFCs was as follows: PFOA (IEF: 1)>PFHpA (0.89)>PFNA (0.61)>PFPeA (0.50)>PFHxS (0.41)>PFHxA (0.38)?PFDA (0.37)>PFBA (0.26)=PFOS (0.26)>PFUnDA (0.15)?PFDoDA and PFBuS (not activated). The structure-activity relationship analysis showed that PFCAs having more than seven perfluorinated carbons had a negative correlation (r=-1.0, p=0.017) between the number of perfluorinated carbons and the IEF of PFCAs, indicating that the number of perfluorinated carbon of PFCAs is one of the factors determining the transactivation potencies of the BS PPAR?. The analysis also indicated that PFCAs were more potent than PFSAs with the same number of perfluorinated carbons. Treatment with a mixture of ten PFCs showed an additive action on the BS PPAR? activation. Using IEFs of individual PFCs and hepatic concentrations of PFCs in the liver of wild Baikal seals, the PFOA induction equivalents (IEQs, 5.3-58 ng IEQ/g wet weight) were calculated. The correlation analysis revealed that the hepatic total IEQs showed a significant positive correlation with the hepatic expression levels of cytochrome P450 4A-like protein (r=0.53, p=0.036). This suggests that our approach may be useful for assessing the potential PPAR?-mediated biological effects of complex mixtures of PFCs in wild Baikal seal population. PMID:21381677

Ishibashi, Hiroshi; Kim, Eun-Young; Iwata, Hisato

2011-04-01

217

Efficient and specific removal of albumin from human serum samples  

Microsoft Academic Search

Patient serum or plasma is frequently monitored for bio- chemical markers of disease or physiological status. Many of the rapidly evolving technologies of proteome analysis are being used to find additional clinically inform- ative protein markers. The unusually high abundance of albumin in serum can interfere with the resolution and sensitivity of many proteome profiling techniques. We have used monoclonal

Laura F. Steel; Michael G. Trotter; Pamela B. Nakajima; Taj S. Mattu; Gregory Gonye; Timothy Block

2003-01-01

218

Novel proton exchange membranes based on cardo poly(arylene ether sulfone/nitrile)s with perfluoroalkyl sulfonic acid moieties for passive direct methanol fuel cells  

NASA Astrophysics Data System (ADS)

A new series of cardo poly(arylene ether sulfone/nitrile)s FSPES-x with perfluoroalkyl sulfonic acid groups have been successfully prepared by the perfluorosulfonic acid lactone ring-opening reaction without using any metal or base catalysts. These materials have been characterized by IR, NMR and TGA. The results indicate that this simple and metal-free method of preparation is highly efficient for controlling both the degree of perfluorosulfonation and the position of the sulfonate group and no side reactions such as crosslinking is observed. The FSPES-x membranes (IEC = 1.17-1.64 m equiv g-1) show the desired characteristics such as good film-forming ability, excellent thermal and mechanical properties, low methanol permeability, high conductivity (up to 0.083 S cm-1 at room temperature), as well as appropriate cell performance compared to Nafion®117. With these properties, such fluorinated sulfonic acid side-chain-type polymers are promising PEM materials for application in fuel cells.

Zheng, Jifu; He, Qingyi; Gao, Nian; Yuan, Ting; Zhang, Suobo; Yang, Hui

219

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

220

High-temperature and photochemical syntheses of C[subscript 60] and C[subscript 70] fullerene derivatives with linear perfluoroalkyl chains  

SciTech Connect

New experimental results on perfluoroalkylation of C{sub 60} and C{sub 70} with the use of R{sub f}I (R{sub f} = CF{sub 3}, C{sub 2}F{sub 5}, n-C{sub 3}F{sub 7}, n-C{sub 4}F{sub 9}, and n-C{sub 6}F{sub 13}), along with a critical overview of the existing synthetic methods, are presented. For the selected new fullerene (R{sub f}){sub n} compounds we report spectroscopic, electrochemical and structural data, including improved crystallographic data for the isomers of C{sub 70}(C{sub 2}F{sub 5}){sub 10} and C{sub 60}(C{sub 2}F{sub 5}){sub 10}, and the first X-ray structural data for the dodecasubstituted perfluoethylated C{sub 70} fullerene, C{sub 70}(C{sub 2}F{sub 5}){sub 12}, which possesses unprecedented addition pattern.

Shustova, Natalia B.; Kareev, Ivan E.; Kuvychko, Igor V.; Whitaker, James B.; Lebedkin, Sergey F.; Popov, Alexey A.; Dunsch, Lothar; Chen, Yu-Sheng; Seppelt, Konrad; Strauss, Steven H.; Boltalina, Olga V. (Freie); (CSU); (Leibniz); (Russ. Acad. Sci.); (Karlsruhe); (UC)

2012-04-30

221

Maternal serum screening.  

PubMed Central

Maternal serum screening (MSS) measures three serum markers: alpha-fetoprotein, human chorionic gonadotropin, and unconjugated estriol, from which the risk of fetal Down syndrome or open neural tube defect is calculated. Initially, 8% of women will have positive results. I present a protocol for investigating these women. Family physicians should be informed about MSS so they can give their patients information and guidance.

Carroll, J. C.

1994-01-01

222

[Determination of electrolytes in serum and plasma].  

PubMed

In clinical chemistry two different quantities are determined for electrolytes: 1) Electrolyte concentration (total) in serum (S) e.g. S-sodium (mmol/l), S-calcium (mmol/l). 2) Electrolyte concentration (ionized) in serum water [S(W)] e.g. S(W)-sodium, ionized (mmol/kg), S(W)-calcium, ionized (mmol/kg) ad 1) For the determination of the electrolyte concentration in serum, various methods are used: Sodium, potassium: Flame atomic emission spectrometry, ion-selective electrodes after dilution of the sample, enzymatic methods; Chloride: Coulometry, absorption spectrometry after chemical reaction, enzymatic method; Calcium, magnesium: Flame atomic absorption spectrometry, flame atomic emission spectrometry (calcium), absorption spectrometry after chemical reaction, enzymatic method (magnesium). A safe and unambiguous medical interpretation of sodium and chloride ion concentration in serum is not possible without knowledge of the water concentration or of the lipid and protein concentration of the individual sample. The same holds true--even though for some other reasons--for calcium concentration in whole serum. The reference intervals of the pertinent ions are valid only for samples, which are "normal" with respect to the size of the electrolyte-free compartment and--depending on the method--the amount of complex-binding ions. ad 2) For the determination of the concentration of the "ionized" or "free" fraction of sodium, potassium, calcium, and magnesium in serum water (or the extracellular water phase of whole blood) the following method is only applicable: Ion selective electrode without dilution of the sample. A save medical interpretation of the ionized electrolyte concentration in serum water is possible without knowledge of the water concentration of the individual sample, because these quantities are independent from the size of the electrolyte-free compartment.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1502823

Külpmann, W R

1992-01-01

223

Strong Lewis acid air-stable cationic titanocene perfluoroalkyl(aryl)sulfonate complexes as highly efficient and recyclable catalysts for C-C bond forming reactions.  

PubMed

A series of strong Lewis acid air-stable titanocene perfluoroalkyl(aryl)sulfonate complexes Cp2Ti(OH2)2(OSO2X)2·THF (X = C8F17, 1·THF; X = C4F9, 2·H2O·THF; X = C6F5, 3) were successfully synthesized by the treatment of Cp2TiCl2 with C8F17SO3Ag, C4F9SO3Ag and C6F5SO3Ag, respectively. In contrast to well-known titanocene bis(triflate), these complexes showed no change in open air over three months. TG-DSC analysis showed that 1·THF, 2·H2O·THF and 3 were thermally stable at 230 °C, 220 °C and 280 °C, respectively. Conductivity measurements showed that these complexes underwent ionic dissociation in CH3CN solution. X-ray analysis results confirmed that 2·H2O·THF and 3 were cationic. ESR spectra showed that the Lewis acidity of 1·THF (1.06 eV) was higher than that of Sc(3+) (1.00 eV) and Y(3+) (0.85 eV). UV/Vis spectra showed a significant red shift due to the strong complex formation between 10-methylacridone and 2·H2O·THF. Fluorescence spectra showed that the Lewis acidity of 2 (?em = 477 nm) was higher than that of Sc(3+) (?em = 474 nm). These complexes showed high catalytic ability in various carbon-carbon bond forming reactions. Moreover, they show good reusability. Compared with 1·THF, 2·H2O·THF and 3 exhibit higher solubility and better catalytic activity, and will find broad applications in organic synthesis. PMID:24950799

Li, Ningbo; Wang, Jinying; Zhang, Xiaohong; Qiu, Renhua; Wang, Xie; Chen, Jinyang; Yin, Shuang-Feng; Xu, Xinhua

2014-08-14

224

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

PubMed

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

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

2013-02-01

225

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

EPA Science Inventory

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

226

Glibenclamide in serum: comparison of high-performance liquid chromatography using fluorescence detector and liquid chromatography\\/mass spectrometry with atmospheric-pressure chemical-ionization (APCI LC\\/MS)  

Microsoft Academic Search

Comparative studies of high-performance liquid Chromatographic and liquid chromatographic\\/mass spectrometric methods for the\\u000a quantitative determination of glibenclamide in patient serum are described. The 4-methylcyclohexyl analogue of glibenclamide\\u000a [N-(4-(?-5-chloro-2-methoxybenzamidoethyl)benzenesulfonyl-N?-(4-methyl-cyclohexyl)-urea] is used as internal standard for\\u000a both methods. After acidification of the sample, the analyte and internal standard are extracted with chloroform. For HPLC\\u000a analysis, the glibenclamide and internal standard are derivatized

F. Susanto; H. Reinauer

1996-01-01

227

Extraction and clean-up strategies for the analysis of poly- and perfluoroalkyl substances in environmental and human matrices.  

PubMed

The rapidly expanding field of per- and polyfluorinated alkyl substances (PFASs) research has resulted in a wide range of analytical methodologies to determine the human and environmental exposure to PFASs. This paper reviews the currently applied techniques for sample pre-treatment, extraction and clean-up for the analysis of ionic and non-ionic PFASs in human and environmental matrices. Solid phase extraction (SPE) is the method of choice for liquid samples (e.g. water, blood, serum, plasma), and may be automated in an on-line set-up for (large volume) sample enrichment and sample clean-up. Prior to SPE, sample pre-treatment (filtration or centrifugation for water or protein precipitation for blood) may be required. Liquid-liquid extraction can also be used for liquid samples (and does not require above mentioned sample pretreatment). Solid-liquid extraction is the commonly applied method for solid matrices (biota, sludge, soil, sediment), but automation options are limited due to contamination from polytetrafluorethylene tubings and parts applied in extraction equipment. Air is generally preconcentrated on XAD-resins sandwiched between polyurethane foam plugs. Clean-up of crude extracts is essential for destruction and removal of lipids and other co-extractives that may interfere in the instrumental determination. SPE, (fluorous) silica column chromatography, dispersive graphitized carbon and destructive methods such as sulphuric acid or KOH treatment can be applied for clean-up of extracts. Care should be taken to avoid contamination (e.g. from sample bottles, filters, equipment) and losses of PFASs (e.g. adsorption, volatilization) during sampling, extraction and clean-up. Storage at -20 degrees C is generally appropriate for conservation of samples. PMID:17349649

van Leeuwen, S P J; de Boer, J

2007-06-15

228

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.

229

Production and EPR characterization of exohedrally perfluoroalkylated paramagnetic lanthanum metallofullerenes: (La@C 82)-(C 8F 17) 2  

NASA Astrophysics Data System (ADS)

A strategy to chemically derivatize the outer sphere of endohedral metallofullerenes by using a fluorous synthesis-partitioning approach has been developed. The newly synthesized materials were found to be paramagnetic species and were characterized by electron paramagnetic resonance spectroscopy (EPR), laser desorption time-of-flight spectrometry (LD-TOF) and electronic absorption spectroscopy (UV-VIS-NIR). The fluorous-phase partitioning method (or liquid-liquid extraction), successfully applied for the first time in fullerene chemistry, aided by multi-stage recycling high performance liquid chromatography (HPLC) resulted in their isolation in isomer-free form. The present study opens the way to organic transformations of fullerene-based materials as a powerful separation technique.

Tagmatarchis, Nikos; Taninaka, Atsushi; Shinohara, Hisanori

2002-04-01

230

In vitro metabolic formation of perfluoroalkyl sulfonamides from copolymer surfactants of pre- and post-2002 scotchgard fabric protector products.  

PubMed

Currently there is a scientific debate on whether fluorinated polymers (or copolymers) are a source, as a result of their degradation and subsequent formation, of perfluorinated carboxylic acids (PFCAs) and perfluorinated alkanesulfonates (PFSAs). The present study investigated whether commercially available fluorinated surfactants, such as Scotchgard fabric protector (3M Company), can be metabolically degraded, using a model microsomal in vitro assay (Wistar-Han rats liver microsomes), and with concomitant formation of PFCAs, PFASs, and/or their precursors. The results showed that the main in vitro metabolite from the pre-2002 product was perfluorooctane sulfonamide (FOSA), and coincident with the detection of the major fabric protector components, which contains the N-ethyl-perfluorooctanesulfonyl chemical moiety (C8F17SO2N(C2H5)-); the main in vitro metabolite of the post-2002 product was perfluorobutane sulfonamide (FBSA), which was coincident with the detection of the major fabric protector components, and contains the N-methyl-perfluorobutanesulfonyl chemical moiety (C4F9SO2N(CH3)-). FOSA or FBSA metabolite concentrations increased over the 0-60 min microsomal incubation period. However, concentrations of their small molecule precursors such as alkylated FOSAs or FBSAs were not detectable (

Chu, Shaogang; Letcher, Robert J

2014-06-01

231

Vanadium in human serum, as determined by neutron activation analysis  

SciTech Connect

Vanadium concentrations have been measured in the serum of 23 healthy subjects by neutron activation analysis, with post-irradiation chemical separation. The values obtained fall in a fairly narrow range (260-1300 ng/L, mean 670 ng/L), which suggests a physiological role for this element. The authors checked the method by analysis of standard (U.S. National Bureau of Standards) water samples and serum samples supplemented with /sup 48/V, and found excellent agreement with expected results in both cases. They consider the reported results for human serum to be more reliable than those obtained by atomic absorption spectroscopy.

Simonoff, M.; Llabador, Y.; Peers, A.M.; Simonoff, G.N.

1984-10-01

232

Integrated Risk Index of Chemical Aquatic Pollution (IRICAP): case studies in Iberian rivers.  

PubMed

The hazard of chemical compounds can be prioritized according to their PBT (persistence, bioaccumulation, toxicity) properties by using Self-Organizing Maps (SOM). The objective of the present study was to develop an Integrated Risk Index of Chemical Aquatic Pollution (IRICAP), useful to evaluate the risk associated to the exposure of chemical mixtures contained in river waters. Four Spanish river basins were considered as case-studies: Llobregat, Ebro, Jucar and Guadalquivir. A SOM-based hazard index (HI) was estimated for 205 organic compounds. IRICAP was calculated as the product of the HI by the concentration of each pollutant, and the results of all substances were aggregated. Finally, Pareto distribution was applied to the ranked lists of compounds in each site to prioritize those chemicals with the most significant incidence on the IRICAP. According to the HI outcomes, perfluoroalkyl substances, as well as specific illicit drugs and UV filters, were among the most hazardous compounds. Xylazine was identified as one of the chemicals with the highest contribution to the total IRICAP value in the different river basins, together with other pharmaceutical products such as loratadine and azaperol. These organic compounds should be proposed as target chemicals in the implementation of monitoring programs by regulatory organizations. PMID:23810233

Fàbrega, Francesc; Marquès, Montse; Ginebreda, Antoni; Kuzmanovic, Maja; Barceló, Damià; Schuhmacher, Marta; Domingo, José L; Nadal, Martí

2013-12-15

233

Serum folates in man.  

PubMed Central

In an aseptic microbiological assay of folate compounds and their breakdown compounds, using Lactobacillus casei, Streptococcus faecalis, and Pediococcus cerevisiae, 4a-hydroxy-5methyl-4,5,6,7-tetrahydrofolate and 5-methyl-5,8-dihydrofolate were inactive under all conditions to all three organisms and 5-methyl-5,6-dihydrofolate was inactive unless ascorbate was present in the incubation medium, and then only to L. casei. 5-Methyltetrahydrofolate was active only for L. casei, and activity in purified samples to S. faecalis was due to trace amounts of folic acid. Analysis of S. faecalis values in the serum in normal subjects and in patients with various disorders showed that levels of 10-formyltetrahydrofolate are raised in coeliac disease, leukaemia, rheumatoid arthritis, and schizophrenia. 5-Methyltetrahydrofolate is readily absorbed by normal human subjects and by patients with pernicious anaemia but poorly absorbed by patients with coeliac disease or leukaemia. 5-Methyl-5,6-dihydrofolate was quickly absorbed by normal human subjects, being reflected by a considerably raised level of 5-methyltetrahydrofolate in serum when sodium bicarbonate was given by mouth before the 5-methyl-5,6-dihydrofolate. These higher levels were comparable to those in patients with pernicious anaemia after oral administration of 5-methyl-5,6-dihydrofolate. Oral 5-methyl-5,8-dihydrofolate and 4a-hydroxy-5-methyl-tetrahydrofolate did not appear as microbiologically active folates in the serum. The findings of this study suggest that the availability for biological utilisation of the major dietary folate compounds will depend on the amount of gastric acidity and of ascorbate in the intestinal chyme. Many may be unavailable for metabolic utilization in the body.

Thien, K R; Blair, J A; Leeming, R J; Cooke, W T; Melikian, V

1977-01-01

234

Structure of Serum Albumin  

NASA Technical Reports Server (NTRS)

Because of its availability, low cost, stability, and unusual ligand-binding properties, serum albumin has been one of the mst extensively studied and applied proteins in biochemistry. However, as a protein, albumin is far from typical, and the widespread interest in and application of albumin have not been balanced by an understanding of its molecular structure. Indeed, for more than 30 years structural information was surmised based solely on techniques such as hydrodynamics, low-angle X-ray scattering, and predictive methods.

Carter, Daniel C.; Ho, Joseph X.

1994-01-01

235

Serum total and bone alkaline phosphatase levels and their correlation with serum minerals over the lifespan of sheep.  

PubMed

This study aimed to assess serum total alkaline phosphatase (ALP) and its bone isoform (BALP) levels during the ageing and in different physiologic states of sheep, in order to expand the knowledge about the variation of these biomarkers over the sheep lifespan. Ninety female sheep were divided into nine groups of various ages and physiological states (dry, lactation and pregnancy). Serum ALP, BALP and mineral levels were determined by commercial immunoassay, molecular absorbance spectrophotometry and chemical luminescence for BALP determination. Serum ALP and BALP decreased as sheep aged, and no statistically significant differences were obtained between ewes in different physiologic states. The continuous decline of serum BALP concentration along the sheep lifespan, namely in mature and old sheep, is a sign of decreasing bone turnover associated with ageing. Serum calcium concentrations increased slightly until 2 years of age and then showed a tenuous but statistically significant decrease in mature sheep, while serum phosphorus maintained an uninterrupted decrease as sheep matured. The knowledge of serum values of bone biomarkers throughout the sheep lifespan may be useful in preclinical orthopaedic research studies and for animal science studies using sheep. PMID:24334071

Sousa, Cristina P; Azevedo, Jorge T; Silva, Amélia M; Viegas, Carlos A; Reis, Rui L; Gomes, Manuela E; Dias, Isabel R

2014-06-01

236

Hair: A Diagnostic Tool to Complement Blood Serum and Urine.  

ERIC Educational Resources Information Center

Trace elements and some drugs can be identified in hair and it seems likely that other organic chemicals will be identifiable in the future. Since hair is so easily collected, stored, and analyzed it promises to be an ideal complement to serum and urine analysis as a diagnostic tool. (BB)

Maugh, Thomas H., II

1978-01-01

237

A SIMPLE RADIOISOTOPIC MICROMETHOD FOR DETERMINATION OF UNSATURATED IRON BINDING CAPACITY OF SERUM  

Microsoft Academic Search

A radioisotopic method for determining serum unsaturated iron-binding ; capacity is presented. Accuracy and precision comparable to chemical methods are ; obtained using 0.2 ml of serum. Hemoglobin at concentrations as high as 1% does ; not interfere and the method can be used in large scale routine application. ; (auth);

N. D. Lee; N. Chiamori

1961-01-01

238

Adherence of Helicobacter pylori to Abiotic Surfaces Is Influenced by Serum? †  

PubMed Central

Helicobacter pylori bacteria cultured in a chemically defined medium without serum readily adhere to a variety of abiotic surfaces. Growth produces microcolonies that spread to cover the entire surface, along with a planktonic subpopulation. Serum inhibits adherence. Initial attachment is protein mediated, but other molecules are responsible for more permanent attachment.

Williams, John C.; McInnis, Karla A.; Testerman, Traci L.

2008-01-01

239

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.

2013-01-01

240

A new stable perfluoroalkyl radical  

SciTech Connect

This paper uses ESR spectroscopy to study the radical formed upon the gamma-irradiation of liquid perfluoro-methyl-2-pentene (PMP). The ESR spectrum of this radical shows a well resolved doublet of triplets with splitting 6.2 and 1.5 mT with additional splitting of each component by 0.25 mT. This ESR corresponds to a radical formed upon the addition of a radical r, in particlular, CF/sub 3/ to PMP.

Allayarov, S.R.; Barkalov, I.M.; Mikhailov, A.I.

1986-01-01

241

Serum laminin in Graves' disease.  

PubMed

We determined serum levels of laminin in 23 patients with Graves' disease (GD) and in 24 patients with toxic nodular goiter (TNG). Elevated levels of soluble laminin were observed in patients with GD prior to treatment (median concentration 1376 ng mL-1 [range 712-2402]), compared to patients with TNG (median 442 ng mL-1 [284-891]), and normal controls (median 492 ng mL-1 [range 235-675], n = 26), respectively. In GD patients serum laminin levels decreased during thiamazole treatment and normalized within 8 weeks of therapy. There was no correlation between serum laminin levels and serum levels of thyroid hormones and/or auto-antibodies, respectively. Whether serum laminin is a marker for alterations of extracellular matrix during GD and release of basement membrane components in the circulation and/or reflects an impaired clearance remains to be elucidated. PMID:7656921

Wenisch, C; Myskiw, D; Narzt, E; Presterl, E; Graninger, W

1995-06-01

242

Determination of maternal serum acetylcholinesterase in pregnancies with fetal neural tube defects.  

PubMed

We have investigated the occurrence of acetylcholinesterase (AChE) (E.C. 3.1.1.7) in fetal serum, amniotic fluid and maternal serum using an immuno-chemical assay-technique employing both polyclonal and monoclonal antibodies. Fetal serum had increased amounts of AChE, which is due to an increase in the 10.5S form of the enzyme. This form was also found in amniotic fluids of pregnancies with a fetal neural tube defect (NTD), but not in normal amniotic fluid. The increase in amniotic fluid AChE was however, not reflected in the maternal serum. PMID:3575265

Sorensen, K; Brodbeck, U; Rasmussen, A G; Norgaard-Pedersen, B

1987-02-01

243

Hepatocellualar carcinoma serum markers.  

PubMed

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in some areas of the world. In most cases, HCC is diagnosed at a late stage. Therefore, the prognosis of patients with HCC is generally poor. The recommended screening strategy for patients with cirrhosis includes the determination of serum ?-fetoprotein (AFP) levels and an abdominal ultrasound every 6 months to detect HCC at an earlier stage. AFP, however, is a marker characterized by poor sensitivity and specificity, and abdominal ultrasound is highly dependent on the operator's experience. In addition to AFP, Lens culinaris agglutinin-reactive AFP (AFP-L3), des-?-carboxy prothrombin (DCP), glypican-3 (GPC-3), osteopontin (OPN), and several other biomarkers (such as squamous cell carcinoma antigen-immunoglobulin M complexes [SCCA-IgM], alpha-1-fucosidase [AFU], chromogranin A [CgA], human hepatocyte growth factor, insulin-like growth factor) have been proposed as markers for the early detection of HCC. For these markers, we describe the mechanisms of production, and their diagnostic and prognosis roles. None of them is optimal; however, when used together, their sensitivity in detecting HCC is increased. Recent research has shown that some biomarkers have mitogenic and migratory activities in the angiogenesis of HCC and are a factor of tumor growth. PMID:22846859

Bertino, Gaetano; Ardiri, Annalisa; Malaguarnera, Michele; Malaguarnera, Giulia; Bertino, Nicoletta; Calvagno, Giuseppe Stefano

2012-08-01

244

Operation of a DNA-Based Autocatalytic Network in Serum  

NASA Astrophysics Data System (ADS)

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

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

245

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

246

Rapid Enzymatic Measurement of Serum Flucytosine Levels.  

National Technical Information Service (NTIS)

A method is provided for the rapid enzymatic determination of serum flucytosine or cytosine. The serum is first incubated with glutamate dehydrogenase to release endogenous ammonia which is measured, and the serum is then incubated with creatinine iminohy...

M. H. Kroll C. M. Huang R. G. Washburn

1987-01-01

247

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

PubMed Central

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.

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

2012-01-01

248

Second Trimester Maternal Serum Screening  

MedlinePLUS

... Serum AFP; MSAFP; msAFP; Triple Screen; Triple Test; Quad Screen; Quadruple Marker Test; 4-marker Screen; Multiple ... inhibin A, is added, it is called a quad screen. Alpha-fetoprotein (AFP) is a protein produced ...

249

Serum Enzymes in Combat Casualties.  

National Technical Information Service (NTIS)

Serum levels of lactic dehydrogenase (LDH), glutamic oxaloacetic transaminase (GOT), and glutamic pyruvic transaminase (GPT) were determined in combat casualties at the time of admission to the hospital and prior to the administration of any treatment. El...

H. K. Sleeman R. L. Simmons C. A. Heisterkamp

1968-01-01

250

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

PubMed Central

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

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

2012-01-01

251

Kinetics of DNA and RNA Hybridization in Serum and Serum-SDS  

PubMed Central

Cancer is recognized as a serious health challenge both in the United States and throughout the world. While early detection and diagnosis of cancer leads to decreased mortality rates, current screening methods require significant time and costly equipment. Recently, increased levels of certain micro-ribonucleic acids (miRNAs) in the blood have been linked to the presence of cancer. While blood-based biomarkers have been used for years in cancer detection, studies analyzing trace amounts of miRNAs in blood and serum samples are just beginning. Recent developments in deoxyribonucleic acid (DNA) nanotechnology and DNA computing have shown that it is possible to construct nucleic-acid-based chemical networks that accept miRNAs as inputs, perform Boolean logic functions on those inputs, and generate as an output a large number of DNA strands that can readily be detected. Since miRNAs occur in blood in low abundance, these networks would allow for amplification without using polymerase chain reaction. In this study, we report initial progress in the development of a DNA-based cross-catalytic network engineered to amplify specific cancer-related miRNAs. Subcomponents of the DNA network were tested individually, and their operation in serum, as well as a mixture of serum with sodium dodecyl sulfate, is demonstrated. Preliminary simulations of the full cross-catalytic network indicate successful operation.

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

2010-01-01

252

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.

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

2014-01-01

253

Chemical Emergencies  

MedlinePLUS

... the case of a terrorist attack with a chemical weapon. Some hazardous chemicals have been developed by military ... there are no guarantees of safety during a chemical emergency, you can take actions to protect yourself. You ...

254

Evaluation of serum and salivary lipid profile: A correlative study  

PubMed Central

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

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

2014-01-01

255

Development of protein-deficient serum-free culture media for adherent cell lines suited for large scale cultivation  

Microsoft Academic Search

Summary Procedures are described for the devlopment of less expensive, protein-deficient serum-free media for the cultivation of mammalian adherent cell lines. Starting with a proteinrich chemically defined, serum-free culture medium, the concentrations of the expensive or highly concentrated proteins, or both, such as bovine serum albumin (BSA), insulin, or transferrin are systematically reduced one after the other until the minimal

Berthold G. D. Bödeker; Guy J. Berg; Ulrich Steiner; Guy Hewlett; H. Dieter Schlumberger

1983-01-01

256

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

Microsoft Academic Search

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

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

2010-01-01

257

Bone mineralisation in premature infants cannot be predicted from serum alkaline phosphatase or serum phosphate  

Microsoft Academic Search

Background: The bone mineral content of premature infants at term is lower than in mature infants at the same postconceptional age. Serum alkaline phosphatase and serum phosphate are often used as indicators of bone mineralisation.Objective: To analyse the association between bone mineral content and serum alkaline phosphatase and serum phosphate.Methods: Serum alkaline phosphatase and phosphate were measured at weekly intervals

J Faerk; B Peitersen; S Petersen; K F Michaelsen

2002-01-01

258

Evaluation of potential health effects associated with serum polychlorinated biphenyl levels  

SciTech Connect

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

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

1986-12-01

259

Serum Myoglobin Levels Predicted from Serum Enzyme Values.  

National Technical Information Service (NTIS)

One-hundred-thirty-two of 337 Marine recruits (39.2%) had demonstrable myoglobinemia on at least one occasion during their first six training days. Serum myoglobin levels were determined by means of a specific and sensitive immunologic assay based on the ...

J. E. Olerud L. D. Homer H. W. Carroll

1975-01-01

260

The relationship between serum cholesterol and serum thyroid hormones in male patients with suspected hypothyroidism.  

PubMed

The relationship between serum cholesterol, thyrotropin, thyroxine and triiodothyronine was investigated in 456 male patients with suspected hypothyroidism. The correlation between serum cholesterol and serum thyroxine (r = 0.0572) and between serum cholesterol and serum triiodothyronine (r = 0.1136) were not significant but the correlation between serum cholesterol and TSH (r = 0.0376) was significant (P < 0.001). The mean serum cholesterol was only significantly increased in the patient groups with a serum TSH greater than 20 mU/L. In 26 patients treated for hypothyroidism with thyroxine replacement there was a significant correlation between the decrease in serum cholesterol and the decrease in serum TSH (r = 0.5334, P < 0.01) but there was poor correlation between the decrease in cholesterol and either the increase in serum triiodothyronine or the increase in serum thyroxine. PMID:8517607

Johnston, J; McLelland, A; O'Reilly, D S

1993-05-01

261

Specific antioxidant properties of human serum albumin  

PubMed Central

Human serum albumin (HSA) has been used for a long time as a resuscitation fluid in critically ill patients. It is known to exert several important physiological and pharmacological functions. Among them, the antioxidant properties seem to be of paramount importance as they may be implied in the potential beneficial effects that have been observed in the critical care and hepatological settings. The specific antioxidant functions of the protein are closely related to its structure. Indeed, they are due to its multiple ligand-binding capacities and free radical-trapping properties. The HSA molecule can undergo various structural changes modifying its conformation and hence its binding properties and redox state. Such chemical modifications can occur during bioprocesses and storage conditions of the commercial HSA solutions, resulting in heterogeneous solutions for infusion. In this review, we explore the mechanisms that are responsible for the specific antioxidant properties of HSA in its native form, chemically modified forms, and commercial formulations. To conclude, we discuss the implication of this recent literature for future clinical trials using albumin as a drug and for elucidating the effects of HSA infusion in critically ill patients.

2013-01-01

262

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.

263

Low protein serum-free medium for antibody-production in stirred bioreactors  

Microsoft Academic Search

Summary A chemically defined serum-free medium was modified with respect to protein content by substituting PEG (polyethylen glycol) for BSA-FA (bovine serum albumin fatty acid complex). The outstanding advantage of this low-protein medium is the excellent support of hybridoma-growth and MAb (monoclonal antibody)-production in stirred bioreactors even when inoculated at low cell concentrations. Using this medium, the secreted MAbs were

Horst D. Blasey; Ursula Winzer

1989-01-01

264

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

Microsoft Academic Search

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

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

2008-01-01

265

Predictors of Serum Chlorinated Pesticide Concentrations among Prepubertal Russian Boys  

PubMed Central

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

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

2013-01-01

266

Radioimmunoassay of human serum serotonin.  

PubMed

A radioimmunoassay for extracted, N-acetylated human serum serotonin (5-hydroxytryptamine) is described. Antisera were raised in rabbits against a conjugate of bovine serum albumin with serotonin hemisuccinamide. Polyethylene glycol in combination with anti-rabbit immunoglobulins was used to separate bound and unbound 125I-Bolton Hunter-serotonin conjugate. Ethanol precipitation of serum proteins was used to extract serotonin, which was subsequently acetylated with acetic anhydride to N-acetyl serotonin. The average recovery was 66%. The minimal detectable concentration of N-acetyl serotonin was 0.012 mumol/l serum (25 fmol per tube). The intra-assay precision (CV) was 6.8% (n = 20) at a level of 0.9 +/- 0.06 mumol/l. The inter-assay CV was 10% at a level of 0.49 +/- 0.049 mumol/l, and 25% (n = 10) at a level of 2.16 +/- 0.53. Analytical recovery of serotonin, corrected for losses during extraction and acetylation, was 99 +/- 13%. The only substance cross-reacting with the antibody was endogenous N-acetyl serotonin. This was detectable when the acetylation step was omitted, and it can be removed by extraction before the acetylation. The observed range for the concentration of serotonin in serum was for 59 women 0.45 - 3.46 (mean +/- SD: 1.37 +/- 0.63 mumol/l) and for 59 men 0.19 - 2.8 (mean +/- SD: 1.18 +/- 0.56 mumol/l). All values are corrected for endogenous N-acetyl serotonin: observed range 0 - 0.18 (mean +/- SD: 0.03 +/- 0.03 mumol/l). PMID:4067515

Manz, B; Kosfeld, H; Harbauer, G; Grill, H J; Pollow, K

1985-10-01

267

Serum Enzyme Changes after Physical Exertion.  

National Technical Information Service (NTIS)

A study of alterations in selected serum enzymes after physical exertion by young males is reported. Mean serum concentrations of glutamic oxalacetic transaminase (SGOT), lactate dehydrogenase and amylase all increase after the performance of vigorous exe...

I. D. Wilson

1968-01-01

268

Serum Lipoprotein Patterns in Liver Disease (34886).  

National Technical Information Service (NTIS)

An agarose gel electrophoretic technique which clearly detects and sharply resolves serum lipoproteins has been applied to the determination of serum lipoprotein patterns in liver diseases. The patterns obtained are characterized by presence of beta-, abs...

M. A. Charles N. M. Papadopoulos

1970-01-01

269

Rifampicin Serum Level in Egyptian Tuberculous Patients.  

National Technical Information Service (NTIS)

This report includes the microbiological determination of Rifampicin (RMP) serum levels in 26 chronic tuberculous Egyptian patients who received the drug for the first time. RMP mean serum levels at 3 and 6 hours after its oral administration in therapeut...

H. H. Youssef J. Sippel K. Sorensen I. A. Mikhail M. E. Mahmoud

1973-01-01

270

Chemical Threats  

MedlinePLUS

Chemical agents are poisonous vapors, aerosols, liquids and solids that have toxic effects on people, animals or plants. They ... hazard to people and the environment. Some chemical agents may be odorless and tasteless. They can have ...

271

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

PubMed

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

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

2014-07-01

272

Home Chemicals  

NSDL National Science Digital Library

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

Fox, Chris

273

Chemical Biology\\/ Chemical Genetics\\/ Chemical Genomics: Importance of Chemical Library  

Microsoft Academic Search

A new field of science, chemical biology\\/ chemical genetics\\/ chemical genomics (cb\\/cg\\/cg) has emerged since the late 1990's, especially in the United States. The NIH Roadmap agenda, Molecular Libraries Screening Center Network (MLSCN), became a drive force to push cb\\/cg\\/cg forward. Cb\\/cg\\/cg studies consist of three methodologies, chemical libraries with small molecules, high-throughput screenings, and computational databases. In this review,

Fumihiko Kugawa; Masaru Watanabe; Fuyuhiko Tamanoi

2007-01-01

274

Chemical sensor  

NASA Technical Reports Server (NTRS)

A sensor for detecting a chemical substance includes an insertion element having a structure which enables insertion of the chemical substance with a resulting change in the bulk electrical characteristics of the insertion element under conditions sufficient to permit effective insertion; the change in the bulk electrical characteristics of the insertion element is detected as an indication of the presence of the chemical substance.

Rauh, R. David (Inventor)

1990-01-01

275

Postpartum Changes in Milk Serum Protein Fractions  

Microsoft Academic Search

Polyaerylamide gel disc electrophoresis was used to study changes in the relative concentration of the fi-lactoglobulin, a- laetalbumin, blood serum albumin, and im- mune globulin in milk serum during the first 21 days post-partum. All four protein fractions were found to be concentrated in cotostrum serum at parturition, with im- mune globulin being a major fraction. A graphic analysis of

R. M. Porter; H. R. Conrad

1967-01-01

276

Prostatic Contribution to Normal Serum Acid Phosphatase  

Microsoft Academic Search

Total and tartrate-labile serum acid phosphatase levels were compared in patients with and without prostates, and in 12 patients before and after cystoprostatectomy. Absence of the prostate seems to make no significant difference to the levels of serum acid phosphatase. There is no justification for referring to the tartrate-labile serum acid phosphatase as “prostatic acid phosphatase.” A substantial incidence of

Donald Dow; Robert H. Whitaker

1970-01-01

277

Factors Influencing the Levels of the Alkaline Phosphatases in Maternal Serum and Cord Serum  

Microsoft Academic Search

By stepwise regression analysis the levels of the alkaline phosphatases in maternal serum and in cord serum were studied in relation to each other and to 19 other factors. The maternal serum heat-stable alkaline phosphatase level was found to be influenced by the alkaline phosphatase level in placental tissue, the placental alkaline phosphatase factor I1 and the maternal serum acid

L. Beckman; G. Beckman; S. S. Magnusson

1971-01-01

278

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

279

SERUM LIPIDS : NEW BIOLOGICAL MARKERS IN DEPRESSION ?  

PubMed Central

Several studies suggest that a low cholesterol concentration is associated with depression. The authors sought to determine whether an association exists between serum lipid concentrations and depression. 28 drug-naive patients of major depression diagnosed according to DSMlll- R criteria were included in the study and severity of depression was measured on Hamilton Rating Scale for Depression. Suicidal intent was assessed on Suicidal Intent Questionnaire. 28 normal healthy controls were selected and matched for age, sex and body-mass index with the depressives. Serum lipid estimations were done in each subject after 12 hours overnight fasting. The main finding of the study is that total serum cholesterol, serum triglycerides and serum LDL cholesterol are decreased while serum HDL cholesterol is increased in depression and these changes were more marked in depressed subjects with definite suicidal intent. On regression analysis, total serum cholesterol was the most important predictive variable of the severity of depression.

Khalid, Abdul; Lal, Narottam; Trivedi, J.K.; Dalal, P.K.; Asthana, O.P.; Srivastava, J.S.; Akhtar, Asif

1998-01-01

280

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.

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

281

Amorphous fluorocarbon polymer (a-C:F) films obtained by plasma enhanced chemical vapor deposition from perfluoro-octane (C8F18) vapor I: Deposition, morphology, structural and chemical properties  

NASA Astrophysics Data System (ADS)

The method of obtaining amorphous fluorocarbon polymer (a-C:F) films by plasma enhanced chemical vapor deposition in a capacitively coupled, 13.56 MHz reactor, from a new monomer, namely perfluoro-octane (C8F18) vapor, is presented. For monomer pressure ranging from 0.2 to 1 Torr and input power density from 0.15 to 0.85 W/cm3, the maximum deposition rate reached 300 nm/min, while 10% monomer dilution with argon led to a deposition rate of 200 nm/min. The film surface and bulk morphologies, chemical and structural compositions were investigated using scanning electron microscopy, x-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. It was revealed that the films have a dense and compact structure. The fluorine to carbon ratio (F/C) of the films was between 1.57 and 1.75, and the degree of cross-linking was between 55% and 58%. The relative amount of perfluoroalkyl (CF2) groups in the films was 29%. The FTIR spectra showed absorption bands corresponding to the different vibrational modes of CF, CF2, and CF3 moieties. .

Biloiu, Costel; Biloiu, Ioana Arabela; Sakai, Yosuke; Suda, Yoshiyuki; Ohta, Akitsugu

2004-01-01

282

Chemical Bonds  

NSDL National Science Digital Library

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

Consortium, The C.

2011-12-11

283

Chemical Composition  

NASA Astrophysics Data System (ADS)

Measurements of the chemical compositions of materials and the levels of certain substances in them are vital when assessing and improving public health, safety and the environment, are necessary to ensure trade equity, and are required when monitoring and improving industrial products and services. Chemical measurements play a crucial role in most areas of the economy, including healthcare, food and nutrition, agriculture, environmental technologies, chemicals and materials, instrumentation, electronics, forensics, energy, and transportation.

May, Willie; Cavanagh, Richard; Turk, Gregory; Winchester, Michael; Travis, John; Smith, Melody; Derose, Paul; Choquette, Steven; Kramer, Gary; Sieber, John; Greenberg, Robert; Lindstrom, Richard; Lamaze, George; Zeisler, Rolf; Schantz, Michele; Sander, Lane; Phinney, Karen; Welch, Michael; Vetter, Thomas; Pratt, Kenneth; Scott, John; Small, John; Wight, Scott; Stranick, Stephan

284

The short-term effect of mustard gas on the serum immunoglobulin levels.  

PubMed

Mustard gas (MG), as a chemical warfare agent was used by the Iraqi army in Iran-Iraq conflict against military men in the battlefield in 1985.The serum levels of IgG, IgA and IgM of patients exposed to MG in the battlefield were measured by single radial immunodiffusion from day 3 up to one month after exposure to MG. The serum levels of IgG in patients showed significant decrease on day 3 after exposure to MG. However, the levels of IgG in the serum samples collected from the patients during 4-18 days after exposure to MG were found to increase. The increase in serum IgG levels in the sera of patients which were collected during 19-31 days after exposure to MG was found to be highly significant, surpassing those from the controls. The levels of serum IgA in patients during one month after exposure to MG showed alterations similar to those of serum IgG, however the serum alterations of the patients IgA, comparing to those of the normal controls were not significant. The serum levels of IgM in patients did not show marked alterations during one month after exposure to MG comparing to those of the normal controls. The initial decrease in serum levels of IgG in patients is discussed in terms of a possible leakage of IgG into the skin blisters and into other severely affected parts of the body such as respiratory system, whereas the subsequent increase in serum IgG is interpreted as due to (auto) antigenic stimulation of the patients' immune systems. PMID:17303924

Keyhani, Abdolhossein; Eslami, Mohammad Bagher; Razavimanesh, Hossein

2007-03-01

285

Immunoassay for human serum hemojuvelin  

PubMed Central

Background Hemojuvelin, a critical regulator of iron homeostasis, is involved in the regulation of hepcidin expression and iron homeostasis. It is expressed both as a membrane-bound form and as a soluble one. Serum hemojuvelin can be produced by secretion following furin cleavage or by proteolytic cleavage of the membrane-bound form by matriptase 2 (TMPRSS6). These forms contribute to down-regulation of hepcidin expression upon iron deficiency or hypoxia. This study describes the development and validation of the first enzyme-linked immunosorbent assay for hemojuvelin in human serum. Design and Methods This assay is based on the use of a recombinant human repulsive guidance molecule-c peptide and a polyclonal antibody against hemojuvelin able to recognize the recombinant peptide and the native soluble hemojuvelin by immunoprecipitation. Results The enzyme-linked immunosorbent assay was validated and appeared to be a robust method with intra- and inter-coefficients of variance ranging from 2.6% to 15%. The assay was able to quantify hemojuvelin levels in a control population within a range from 0.88 to 1.14 mg/L. Patients with iron-refractory iron-deficiency anemia with a mutation in the TMPRSS6 gene were found to have lower levels of circulating hemojuvelin than those in healthy patients. The enzyme-linked immunosorbent assay also showed that soluble hemojuvelin levels were significantly higher in patients with anemia of chronic disease than in control individuals. Conclusions This enzyme-linked immunosorbent assay has a good specificity and sensitivity for the quantification of soluble hemojuvelin in human serum and could be a valuable aid to understanding the physiological role of this protein.

Brasse-Lagnel, Carole; Poli, Maura; Lesueur, Celine; Grandchamp, Bernard; Lavoinne, Alain; Beaumont, Carole; Bekri, Soumeya

2010-01-01

286

Serum Transaminases during Salicylate Therapy  

PubMed Central

In 8 out of 32 juvenile patients suffering from chronic polyarthritis and in one patient with dermatomyositis, raised transaminase levels were found; the salicylate level was above 35 mg/100 ml in all except one. Reduction in the salicylate level led to a prompt fall in the serum transaminases. Despite a rise in alkaline phosphatase in three cases there was no other evidence of liver dysfunction in the children. Only one of the adults showed a rise in transaminase levels, and she had mild cirrhosis.

Russell, A. S.; Sturge, R. A.; Smith, M. A.

1971-01-01

287

Reduction of blood serum cholesterol  

NASA Technical Reports Server (NTRS)

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

Winitz, M. (inventor)

1974-01-01

288

A STUDY OF SERUM SALVARSANIZED IN VITRO  

PubMed Central

1. Addition of salvarsan to serum in vitro produces a spirocheticidal mixture which is increased in potency by heating. 2. The heated serum of salvarsan-treated patients is more spirocheticidal if it has been in contact with the clot over night than if it has been separated immediately after coagulation. This is not true with the serum from blood which has been salvarsanized in vitro. 3. The addition of salvarsan directly to serum produces a more potent mixture than results from the serum from blood to which salvarsan has been added in equivalent amounts. 4. The increase in activity of salvarsanized serum produced by heating to 56°C. is due in part to the removal of inhibitory substances in the serum and in part to a direct increase in spirocheticidal power in the heated salvarsan. 5. Both salvarsanized and neosalvarsanized serum are rendered more spirocheticidal by heating. 6. A more active spirocheticidal mixture is produced by mixing small amounts of salvarsan with the serum of a salvarsan-treated patient than by mixing the same amount with normal serum.

Swift, Homer F.

1916-01-01

289

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

290

High-performance liquid chromatographic determination of seratrodast and its metabolites in human serum and urine.  

PubMed

A high-performance liquid chromatographic (HPLC) method was developed for the simultaneous determination of seratrodast, a new antiasthmatic drug, and its metabolites (M-I to M-III) in human serum and urine. The method for serum and urine with and without enzymatic hydrolysis using beta-glucuronidase involved liquid-liquid extraction and chemical oxidation with iron(III) chloride. The compounds in the extract were analyzed using HPLC with UV detection at 266 nm. The detection limits of seratrodast, M-I, M-II and M-III in serum and urine were 5-10 and 5-20 ng/ml, respectively, and those of deconjugated compounds in urine were 10-50 ng/ml. The method was applicable for human serum and urine from clinical trials. PMID:9518166

Ohta, R; Amano, T; Yamashita, K; Motohashi, M

1997-12-19

291

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

292

Chemical agents and chemical terrorism.  

PubMed

Chemical terrorism is a new threat to the security of mankind, which scale essentially exceeds the impact of use of the most modem firearms. At present time all over the world threats from different radical elements to use radioactive materials, potent poisonous substances and pathogenic microorganisms for terrorist purposes became more frequent. High-toxic chemical substances can fall in terrorist hands through wide range of sources. Potentially misused types of chemical compounds are discussed in this article. PMID:15141987

Patocka, J; Fusek, J

2004-03-01

293

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

294

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)

295

Novel Utilization of Serum in Tissue Decellularization  

PubMed Central

Decellularization of native tissues is a promising technique with numerous applications in tissue engineering and regenerative medicine. However, there are various limitations of currently available decellularization methods, such as alteration of extracellular matrix mechanics and restricted use on certain tissues. This study was conducted to explore the effect of serum on the decellularization of various types of tissues. Fetal bovine serum–containing cell culture medium endothelial growth media-2 removed DNA but not cellular ?-actin from human umbilical artery after detergent treatment, without compromising the tissue mechanical strength assessed by burst pressure. In addition, the effect of serum-containing endothelial growth media-2 on DNA removal was replicated in other types of tissues such as tissue-engineered vessels and myocardium. Other types of serum, including human serum, were also shown to remove DNA from detergent-pretreated tissues. In conclusion, we describe a novel utilization of serum that may have broad applications in tissue decellularization.

Gui, Liqiong; Chan, Stephen A.; Breuer, Christopher K.

2010-01-01

296

Serum liver enzymes in Turner syndrome  

Microsoft Academic Search

Increased serum concentrations of liver enzymes are sometimes observed, in the absence of clinical symptoms of liver disease,\\u000a in patients with Turner syndrome. The purpose of this study was to evaluate, in our Turner patients, serum liver enzyme levels\\u000a and to find a cause for their increase. In 70 Turner patients, serum AST, ALT, GGT levels were evaluated every 6

D. Larizza; M. Locatelli; L. Vitali; C. Viganò; V. Calcaterra; C. Tinelli; M. G. Sommaruga; A. Bozzini; R. Campani; F. Severi

2000-01-01

297

Serum enzymes in heat stroke: prognostic implication  

Microsoft Academic Search

We measured serum creatine kinase (CK), lactate dehy- drogenase (LD), aspartate aminotransferase (AST), and serum alanine aminotransferase (ALT) in 26 heat stroke (HS) victims and 10 control (non-heat-exhausted) sub- jects during annual Hajj in Makkah, Saudi Arabia. On admission to the HS treatment unit, serum CK, AST, ALT, and LD were higher in HS victims than controls (P <0.05), and

Abdulaziz H. Alzeer; Mohsen A. F. El-Hazmi; Arjumand S. Warsy; Ziauddin A. Ansari; Mohammed S. Yrkendi

298

Serum biochemical parameters of Acipenser persicus  

Microsoft Academic Search

Serum biochemical parameters are important aspects in the management of endangered species, such as Acipenser persicus. The values of these parameters can be used for confirming the maturity and for monitoring any changes in the quality of\\u000a waters and related soils. Serum samples of 44 A. persicus fishes were analyzed and their serum parameter values were determined as Mean±SD in

F. Asadi; M. Masoudifard; A. Vajhi; K. Lee; M. Pourkabir; P. Khazraeinia

2006-01-01

299

Serum soluble fas levels in ovarian cancer  

Microsoft Academic Search

Objective: To determine the value of serum soluble Fas levels as a prognostic marker for survival of women with ovarian cancer and as a discriminator between benign and malignant adnexal masses.Methods: Serum soluble Fas levels were measured with an enzyme-linked immunosorbent assay in 52 women with ovarian cancer, 30 women with benign ovarian cysts, and 35 healthy women.Results: Median serum

Lukas Hefler; Klaus Mayerhofer; Alessandra Nardi; Alexander Reinthaller; Christian Kainz; Clemens Tempfer

2000-01-01

300

Disturbance of Serum Viscosity in Diabetes Mellitus  

PubMed Central

The serum viscosity of diabetic patients has been found to be increased. The elevation averaged 8% above healthy subjects and 6% above nondiabetic patients. The serum viscosity elevation was greater when diabetic sequelae associated with microangiopathy were present. No relation of serum viscosity to age, sex, obesity, duration of disease, or type of treatment was demonstrated. Serum total protein and glucose levels were found to be correlated with serum viscosity, and increases in their serum concentrations were observed in diabetes. Analysis demonstrated that their elevation did not explain either the viscosity increase or the difference in viscosity between diabetics with and without sequelae. Intrinsic viscosity, abbreviated [?], is a concentration-independent solute property related to molecular shape. [?] was found to be 7% higher in diabetic than in normal serum. The [?] difference accounted for at least half of the serum viscosity elevation. The rest of the increase was due to increased serum protein level and increased nonprotein solids, presumably glucose and lipid. Associated with increased [?] was a decline in albumin: globulin ratio and elevation of the acute phase reactant proteins, ?1-acid glycoprotein, ?1-antitrypsin, haptoglobin, and ceruloplasmin. Studies comparing diabetic and normal serum fractionated by using 21.5% sodium sulfate showed that changes in [?] were attributable to changes in serum protein composition rather than an inherent qualitative disturbance of protein present in one of the fractions. Since serum viscosity is elevated in early diabetes, it may be a part of the metabolic disturbance of diabetes and could play a role in the development of diabetic microangiopathy.

McMillan, Donald E.

1974-01-01

301

Serum Proteins of Germ-Free Rats Fed Water-Soluble Diets.  

National Technical Information Service (NTIS)

The report presents data on serum proteins of germfree rats fed a chemically defined, water-soluble 'antigen free' diet which was filter-sterilized. This type of diet, composed almost entirely of low-molecularweight compounds and free of material of bacte...

B. S. Wostmann G. B. Olson J. R. Pleasants

1964-01-01

302

Serum proteins and enzymes in pregnant rats treated with epoxy resin or triethylenetetraamine stabilizer  

Microsoft Academic Search

A study was made of the serum and amniotic fluid levels of several acute phase reactants (seromucoid, haptoglobin, and sialic acid) and enzymatic activities (lactate dehydrogenase, leucylnaphthylamidase, ?-glutamyltranspeptidase, aminotransferases, cholmesterase, and alkaline and acid phosphatases) in pregnant and nonpregnant rats treated with epoxy resin Epidian 5 or triethylenetetraamine stabilizer. Changes produced by the action of the chemicals were similar, including

W. Dobryszycka; M. Warwas; A. Woytofi; J. Woyto?; J. Szacki

1974-01-01

303

Correlates of serum dioxin to self-reported exposure factors.  

PubMed

The aim of the current analysis was to examine the determinates of lipid-adjusted body levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) from occupational histories, age, body mass index, and self-reported information from a questionnaire. We collected serum from 346 workers at a New Zealand chemical plant that manufactured and formulated the herbicide, 2,4,5-trichlorophenoxyacetic acid (2,4,5-T). Age, body mass index, and employment history were significant determinates of TCDD. The self-reported data on occupation, residence, and general diet were not predictive of serum levels and we observed no evidence of increased TCDD levels from living close to the site. For participants with putative occupational exposure, employment history and personal factors were important to understand the range of TCDD serum levels. For employees without direct occupational exposure, and resulting lower dioxin levels, we recommend further efforts to develop and validate questionnaires to better evaluate environmental sources of dioxins. PMID:20018278

Burns, C J; Collins, J J; Humphry, N; Bodner, K M; Aylward, L L; McBride, D

2010-02-01

304

Interactions of lecithinized superoxide dismutase with serum proteins and cells.  

PubMed

Superoxide dismutase covalently bound to four lecithin molecules (PC-SOD) is known to be retained in circulating blood for a prolonged period and has a high affinity for cells, resulting in beneficial therapeutic effects in animal disease models. In this study, we evaluated the interaction of PC-SOD with biological components, such as serum proteins and cells, to clarify the mechanism underlying the improved pharmacokinetics of SOD induced by lecithin chemical modification (lecithinization). PC-SOD was distributed in the plasma but not in blood cells after being added to the blood. PC-SOD formed a complex with serum protein(s) such as albumin, whereas unmodified SOD did not. The cellular content of PC-SOD was markedly higher than that of unmodified SOD, and was distributed in lysosomes. The pathway associated with the cellular uptake was found to involve clathrin-/caveolae-independent and cholesterol-sensitive endocytosis. Overall, our data indicated that the increased hydrophobicity of lecithinized SOD enhanced its association to both serum protein(s) and plasma membrane microdomains. The former inhibited SOD excretion and promoted long-term retention in circulating blood, whereas the latter enhanced internalization into cells via endocytosis. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:1987-1994, 2014. PMID:24867597

Ishihara, Tsutomu; Nara, Shunsuke; Mizushima, Tohru

2014-07-01

305

Chemical Peeling  

MedlinePLUS

... to Ask Before a Cosmetic Procedure Chemical Peeling (AAD pamphlet) The Lunchtime Peel: What It Can Do ... et al , editors. Fitzpatrick’s Dermatology in General Medicine . 7 th edition. United States of America, McGraw Hill ...

306

Unnecessary Chemicals  

ERIC Educational Resources Information Center

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

Johnson, Anita

1978-01-01

307

Chemical Peels  

MedlinePLUS

... a brow lift, eye lift or soft-tissue filler injection. Mild scarring and certain types of acne also can be treated with chemical peels. In addition, pigmentation of the skin in the form of sun spots, age spots, ...

308

Chemical Exposure  

MedlinePLUS Videos and Cool Tools

... 2014 Related MedlinePlus Pages Environmental Health Hormones Transcript Phthalates are a group of chemicals used to make ... the ban has helped lower exposure to some phthalates, while opening the door to others. Researchers looked ...

309

Serum alkaline phosphatase levels associate with elevated serum C-reactive protein in chronic kidney disease  

Microsoft Academic Search

High serum alkaline phosphatase concentrations are associated with elevated serum C-reactive protein (CRP) levels in the general population. To examine whether this association is independent of serum vitamin D levels or modified in chronic kidney disease (CKD), we determined if such associations exist using data from the National Health and Nutrition Examination Survey III of 14,420 adult participants in which

Sriharsha Damera; Kalani L Raphael; Bradley C Baird; Alfred K Cheung; Tom Greene; Srinivasan Beddhu

2011-01-01

310

Gamma-glutamyl transferase activity in fetal serum, maternal serum, and amniotic fluid during gestation  

Microsoft Academic Search

Gamma-glutamyl transferase activity was measured in fetal serum, maternal serum, and amniotic fluid in 173 pregnancies from 15 to 40 weeks' gestation. Fetal serum was obtained in the second trimester by fetoscopy and in the third trimester by umbilical cord puncture at caesarian section or vaginal delivery. Enzyme activities in maternal blood (10 IU\\/1, SD 2) and fetal blood (88

C Moniz; K H Nicolaides; D Keys; C H Rodeck

1984-01-01

311

Dietary influences on serum lipids and lipoproteins  

Microsoft Academic Search

Substantial data are available to indicate that the diet influences serum levels of cholesterol and lipoproteins. These data are derived from studies in laboratory animals, from epidemiologic studies, and from human investigations. Most research has focused on effects of diet on serum total cholesterol concentrations. In recent years, however, attention has shifted to individual lipoproteins, Le., low density lipoproteins (LDL),

Scott M. Grundy; Margo A. Denke

312

Serum Cholesterol Binding Reserve in Uremia.  

National Technical Information Service (NTIS)

Serum lipid abnormalities were evaluated in 53 patients (40 men and 23 women) undergoing maintenance hemodialysis and 22 non-uremic patients (14 men and 8 women) with the nephrotic syndrome. Serum levels of cholesterol, triglycerides and high-density-lipo...

G. O. Perez S. L. Hsia

1978-01-01

313

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

314

Serum Corticosteroid Binding Following Thermal Injury (36257).  

National Technical Information Service (NTIS)

An adsorption technique has been adapted to measure both the total corticosteroid-binding capacity (CBC) and corticosteroid-binding globulin (CBG) capacity of rat serum following thermal injury. A maximum increase in the rat serum CBC was seen 4 days foll...

G. H. Mudge

1971-01-01

315

Serum selenium levels in chronic lymphocytic leukemia  

PubMed Central

Background: Selenium is a trace mineral which has the role of multiple biologic functions. In free-living animals and humans, selenium is mostly in the form of two selenium-containing amino acids as selenocysteine and selenomethionine. The present study aimed to obtain more data on the relationship between serum selenium in chronic lymphocytic leukemia (CLL). Materials and Methods: Serum selenium levels were measured in 51 patients with chronic lymphocytic leukemia (CLL) as patients group and in 40 non-hospitalized healthy individuals as control group. Results: Selenium was recognized by atomic absorption spectrometer. Decreased mean serum selenium concentrations were observed in the group with chronic lymphocytic leukemia as compared to normal ones (P = 0.005). Serum selenium concentrations were examined in stages 0 and I. They observed a significant difference between the mean serum concentrations of selenium in stage 0, I and II and that of stage IV and V patients with CLL (P = 0.01). The groups were compared and significant differences were observed i.e., low serum selenium levels in the stage III and IV CLL (P = 0.001). The second selenium test was designed in 21 out of 48 patients within 10 weeks from the beginning of chemotherapy. Serum selenium concentration was tested again in 21 patients, and significant differences have been observed between the time before the treatment and after it (P = 0.02). Conclusions: Our results show that in patients with CLL the mean serum selenium levels are lower than that of normal.

Azarm, Taleb; Fazilati, Mohamad; Azarm, Hoda; Azarm, Arezo

2013-01-01

316

Vitamin E serum levels in Rett syndrome  

Microsoft Academic Search

In order to study the role of vitamin E in the pathogenesis of Rett syndrome (RS), we analysed vitamin E serum levels in twenty-eight patients affected by this disorder. We found lower vitamin E serum levels in nine cases (32.1%). These results indicated that the oxidative free radical metabolism may be impaired in a significant percentage of Rett syndrome patients

Patrizia Formichi; Carla Battisti; Maria Teresa Dotti; Giuseppe Hayek; Michele Zappella; Antonio Federico

1998-01-01

317

Association of serum albumin and mortality risk  

Microsoft Academic Search

Reduced levels of serum albumin concentration, a routine blood test, within the “normal” range have been reported to be associated with mortality risk. The literature is reviewed, with a focus on cohort studies meeting specified criteria, and findings are summarized. In studies of many populations, comprising healthy subjects and patients with acute or chronic illness, serum albumin concentration is inversely

Philip Goldwasser; Joseph Feldman

1997-01-01

318

Seasonal Variations of Serum Lipids and Apoproteins  

Microsoft Academic Search

Seasonal variations of blood lipids, which must be considered when performing long-term studies, could be partially due to dietary changes. In the present study, serum lipid parameters were measured each month for 1 year in nuns living in a monastery, whose diet was perfectly regular and controlled. The serum lipid variations observed consisted mainly of an increase in total cholesterol,

J. C. Buxtorf; M. F. Baudet; C. Martin; J. L. Richard; B. Jacotot

1988-01-01

319

Serum YKL-40 and colorectal cancer.  

PubMed

YKL-40 is a mammalian member of the chitinase protein family. Although the function of YKL-40 is unknown, the pattern of its expression suggests a function in remodelling or degradation of extracellular matrix. High serum YKL-40 has been found in patients with recurrent breast cancer and has been related to short survival. In the present study we analysed YKL-40 in preoperative sera from patients with colorectal cancer and evaluated its relation to survival. Serum YKL-40 was determined by RIA in 603 patients. Survival after operation was registered, and median follow-up time was 61 months. Three hundred and forty patients died. Sixteen per cent of the patients with Dukes' A, 26% with Dukes' B, 19% with Dukes' C and 39% with Dukes' D had high serum YKL-40 levels (adjusted for age). Analysis of serum YKL-40 as a continuous variable showed an association between increased serum YKL-40 and short survival (P < 0.0001). Patients with high preoperative serum YKL-40 concentration had significantly shorter survival than patients with normal YKL-40 (HR = 1.7; 95% CI: 1.3-2.1, P < 0.0001). Multivariate Cox analysis including serum YKL-40, serum CEA, Dukes' stage, age and gender showed that high YKL-40 was an independent prognostic variable for short survival (HR = 1.4; 95% CI: 1.1-1.8, P = 0.007). These results suggest that YKL-40 may play an important role in tumour invasion. PMID:10188896

Cintin, C; Johansen, J S; Christensen, I J; Price, P A; Sørensen, S; Nielsen, H J

1999-03-01

320

Reactions of trimethylphosphine analogues of auranofin with bovine serum albumin  

SciTech Connect

The reactions of bovine serum albumin (BSA) with (trimethylphosphine)(2,3,4,6-tetra-O-acetyl-1-thio-..beta..-D-glucopyranosato-S)gold(I), Me/sub 3/PAuSAtg, and its chloro analogue, Me/sub 3/PAuCl, were studied to develop insights into the role of the phosphine ligand in the serum chemistry of the related antiarthritic drug auranofin (triethylphosphine)(2,3,4,6-tetra-O-acetyl-1-thio-..beta..-D-glucopyranosato-S)gold(I). /sup 31/P NMR spectroscopy, protein modification, and gel-exclusion chromatography methods were employed. Comparison of the reactions of the methyl derivatives to the previously reported reactions of auranofin and Et/sub 3/PAuCl with BSA demonstrated that similar chemical species are formed but revealed three major differences. Despite these differences, the results for the methyl analogues provide important confirmation for previously developed chemical models of auranofin reactions in serum. Me/sub 3/PO was not observed in reaction mixtures lacking tetraacetylthioglucose (AtgSH); this result affirms the role of AtgSH, displaced by the reaction of Me/sub 3/PAuSAtg at Cys-34, in the generation of the phosphine oxide (an important metabolite in vivo). The weak binding sites on albumin react with Me/sub 3/PAuCl, but not Me/sub 3/PAuSAtg, demonstrating the importance of the strength and reactivity of the anionic ligand-gold bond on the reactions of auranofin analogues. The gold binding capacity of albumin is enhanced after Me/sub 3/PO is formed, consistent with reductive cleavage of albumin disulfide bonds by trimethylphosphine. 24 references, 2 figures, 3 tables.

Isab, A.A.; Shaw, C.F. III; Hoeschele, J.D.; Locke, J.

1988-10-05

321

Effectiveness of autologous serum as an alternative to fetal bovine serum in adipose-derived stem cell engineering.  

PubMed

In cell culture, medium supplemented with fetal bovine serum is commonly used, and it is widely known that fetal bovine serum supplies an adequate environment for culture and differentiation of stem cells. Nevertheless, the use of xenogeneic serum can cause several problems. We compared the effects of four different concentrations of autologous serum (1, 2, 5, and 10%) on expansion and adipogenic differentiation of adipose-derived stem cells using 10% fetal bovine serum as a control. The stem cells were grafted on nude mice and the in vivo differentiation capacity was evaluated. The isolation of adipose-derived stem cells was successful irrespective of the culture medium. The proliferation potential was statistically significant at passage 2, as follows: 10% autologous serum > 10% fetal bovine serum = 5% autologous serum > 2% autologous serum = 1% autologous serum. The differentiation capacity appeared statistically significant at passage 4, as follows: 10% fetal bovine serum > 10% autologous serum = 5% autologous serum > 2% autologous serum = 1% autologous serum. Ten percent autologous serum and 10% fetal bovine serum had greater differentiation capacity than 1 and 2% autologous serum in vivo, and no significant difference was observed between the groups at ? 5% concentration at 14 weeks. In conclusion, 10% autologous serum was at least as effective as 10% fetal bovine serum with respect to the number of adipose-derived stem cells at the end of both isolation and expansion, whereas 1 and 2% autologous serum was inferior. PMID:22972165

Choi, Jaehoon; Chung, Jee-Hyeok; Kwon, Geun-Yong; Kim, Ki-Wan; Kim, Sukwha; Chang, Hak

2013-09-01

322

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.

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

2010-01-01

323

Development of serum hexosaminidase activity in infants.  

PubMed

Serum activity of hexosaminidases A and B has been measured to identify patients with Tay-Sachs and Sandhoff diseases, and may also be influenced by other clinical conditions including neonatal necrotizing enterocolitis. We have characterized the normal developmental pattern of hexosaminidase activity in serum by measuring this enzyme activity in 61 neonates of 27-40 weeks gestation who were followed from birth to age 4-8 weeks. Total serum hexosaminidase activity significantly increased with postnatal and gestational age, and with initiation of enteral feeding. We conclude that serum hexosaminidase activity in infants with clinical conditions that may influence serum activity of this enzyme must be compared to that in normal infants of similar gestational and postnatal ages. PMID:3082372

Shattuck, K E; Richardson, C J; Rassin, D K; Lobe, T E

1986-01-01

324

Culture of chondrocytes in medium supplemented with fetal calf serum or a serum substitute: Ultroser G.  

PubMed

Fetal calf serum and a serum substitute, Ultroser G, were compared for their effects on the growth curves, clonal growth and cell cycle progression of rabbit chondrocytes in primary culture and during at least three cell passages and included a screen for the maintenance of cartilage-like differentiation i.e. the presence of type II collagen. Proliferation was also compared with another serum substitute, Nu-Serum. Ultroser G is shown to be equivalent to fetal calf serum as far as chondrocyte proliferation is concerned, clonal growth is improved and biosynthesis of type II collagen is maintained in primary culture. PMID:6241000

Ronot, X; Sene, C; Boschetti, E; Hartmann, D J; Adolphe, M

1984-01-01

325

Goat serum, a substitute of bovine serum in cultivation of Babesia bovis.  

PubMed

Babesia bovis (a Mexican isolate) was cultivated in MASP culture system using goat serum in various concentrations as substitute of bovine serum. It was observed that 20% goat serum + 20% bovine serum + 60% Parker's medium 199 supported the growth of the parasite, which was maintained in this medium through 8 subcultures. The soluble exoantigen (vaccine) present in the culture supernatant is to be quantified and tested in vitro. Goat serum from slaughterhouses may be utilized for in vitro cultivation of the parasite and, expectedly, production of vaccine. This study may prove to be useful in reducing the cost of vaccine at least in tropical countries. PMID:1750362

Mishra, A K; Clabaugh, G; Kakoma, I; Ristic, M

1991-01-01

326

Effects of chemical structure on the dynamic and static surface tensions of short-chain, multi-arm nonionic fluorosurfactants.  

PubMed

Fluorinated surfactants with short perfluoroalkyl chains (R(F)) as potential substitutes for the environmentally questionable, long R(F) systems are presented. Three types of nonionic hydrophilic-fluorophilic amphiphiles are synthesized and evaluated based on surface activity in equilibrated (static) and non-equilibrated (dynamic) states. Furthermore, several mono- and disaccharide-based fluorosurfactants are also examined as potential non-bioaccumulative alternatives. A correlation between the chemical structure and resulting surface properties is made by comparing R(F) length, number and size, alkyl-spacer, and hydrophilic moieties. Based on dynamic and static surface tension experiments, the effects of surfactant structure are summarized to provide a basis for the future design of fluorosurfactants. We have found that surfactants with more perfluorinated chains tend to have a higher surface tension reduction, but typically result in slower dynamic behaviors. Using the presented structural characteristics, surfactants with R(F)<4 can be prepared with static surface tensions as low as 18.1mN/m or reduce surface tension within milliseconds. PMID:24910063

Schuster, Thomas; Krumpfer, Joseph W; Schellenberger, Steffen; Friedrich, Reiner; Klapper, Markus; Müllen, Klaus

2014-08-15

327

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

328

Determination of cefatrizine in serum and urine by reversed-phase high-performance liquid chromatography.  

PubMed

A fast and simple high-performance liquid chromatographic procedure for the determination of cefatrizine, an orally active cephalosporin, in serum and urine is proposed. Reversed-phase liquid chromatography on the octoadecylsilane chemically bonded microparticulate packing, using methanol in 0.03 M sodium phosphate buffer (pH 5) as eluent, was used to separate and quantitate the antibiotic. The samples were analysed after deproteinization with trichloroacetic acid and injection of the clear supernatant. The accuracy and reproducibility of the procedure were investigated by determination of the cefatrizine content in spiked serum and urine samples, using cephradine as the internal standard. PMID:546870

Crombez, E; Van der Weken, G; Van den Bossche, W; De Moerloose, P

1979-05-11

329

Serum and Urinary NGAL in Septic Newborns  

PubMed Central

Neutrophil gelatinase-associated lipocalin (NGAL) is postulated to be a potentially new and highly specific/sensitive marker of acute kidney injury (AKI). The aim of this study was to assess the impact of inflammation on serum and urine NGAL in newborns that were treated due to infection. We determined serum and urine NGAL concentrations in 73 infants (51 with sepsis; 22 with severe sepsis) admitted to the Intensive Care Unit in the first month of life, for three consecutive days during the course of treatment for infection. 29 neonates without infection served as the control group. Septic patients, in particular, severe sepsis patients, had increased serum and urinary NGAL levels in the three subsequent days of observation. Five septic patients who developed AKI had elevated serum and urinary NGAL values to a similar extent as septic neonates without AKI. A strong correlation was found between the concentration of serum and urinary NGAL and inflammatory markers, such as CRP and procalcitonin. Serum and urinary NGAL levels were also significantly associated with NTISS (neonatal therapeutic intervention scoring system) values. We conclude that increased serum and urinary NGAL values are not solely a marker of AKI, and more accurately reflect the severity of inflammatory status.

Suchojad, Anna; Majcherczyk, Malgorzata; Jadamus-Niebroj, Danuta; Owsianka-Podlesny, Teresa; Brzozowska, Aniceta

2014-01-01

330

Selected Serum Enzymes as Indicators of Changes in Physical Condition.  

National Technical Information Service (NTIS)

Observations were made on serum glutamio oxalacetic transaminase (SGOT), serum lactic dehydrogenase (SLDH), and serum creatine phosphokinase (SCPK) levels of dogs before, during, and after a vigorous program of training and 'overtraining.' It was not poss...

P. J. Rasch J. S. Bird

1969-01-01

331

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

PubMed Central

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

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

1996-01-01

332

Killing of Brucella abortus by bovine serum.  

PubMed Central

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

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

1988-01-01

333

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.

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

2013-01-01

334

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.

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

2014-01-01

335

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

336

Chemical Wonders  

NSDL National Science Digital Library

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

Integrated Teaching And Learning Program

337

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.

338

Amebicidal activity of wild animal serum.  

PubMed

The sera of 16 species of wild animals representing 5 classes of vertebrates were assayed for amebicidal activity against species of Naegleria. The greatest activity was observed for sera of bullfrogs, muskrats, and raccoons, all of which are animals associated with water. In contrast, the sera from animals such as toads, box turtles, sparrows, and squirrels exhibited minimal or no amebicidal activity. In general, pathogenic Naegleria tended to be less susceptible than nonpathogenic Naegleria to the lytic effect of raccoon serum. Heat-inactivated serum was not amebicidal, suggesting that perhaps complement may be involved in the serum-mediated lysis of amebas. PMID:9267424

John, D T; Smith, B L

1997-08-01

339

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...

340

Autologous Serum Therapy in Chronic Urticaria  

PubMed Central

Autologous serum therapy is a promising therapy for treatment resistant urticaria. This is useful in developing countries as this is economical option. Minimum instruments like centrifuge, syringe and needles are required for the procedure.

Patil, Sharmila; Sharma, Nidhi; Godse, Kiran

2013-01-01

341

(PCG) Protein Crystal Growth Horse Serum Albumin  

NASA Technical Reports Server (NTRS)

Horse Serum Albumin crystals grown during the USML-1 (STS-50) mission's Protein Crystal Growth Glovebox Experiment. These crystals were grown using a vapor diffusion technique at 22 degrees C. The crystals were allowed to grow for nine days while in orbit. Crystals of 1.0 mm in length were produced. The most abundant blood serum protein, regulates blood pressure and transports ions, metabolites, and therapeutic drugs. Principal Investigator was Edward Meehan.

1995-01-01

342

Human serum protein fractionation by gel filtration  

PubMed Central

The development of a quantitative immunological technique using polyvalent antiserum permits a more logical approach to the fractionation of complex protein mixtures. In this study whole serum was separated by conventional gel filtration and the fractions obtained were analysed. This demonstrates over 60 immunologically distinct serum proteins. Because the current terminology is inadequate to describe this number of proteins, a temporary numerical nomenclature has been used. ImagesPLATE 4PLATE 5PLATE 1PLATE 2PLATE 3

Freeman, T.; Smith, J.

1970-01-01

343

Analysis of the human serum proteome  

Microsoft Academic Search

Changes in serum proteins that signal histopathological states, such as cancer, are useful diagnostic and prognostic biomarkers.\\u000a Unfortunately, the large dynamic concentration range of proteins in serum makes it a challenging proteome to effectively characterize.\\u000a Typically, methods to deplete highly abundant proteins to decrease this dynamic protein concentration range are employed,\\u000a yet such depletion results in removal of important low

King C. Chan; David A. Lucas; Denise Hise; Carl F. Schaefer; Zhen Xiao; George M. Janini; Kenneth H. Buetow; Haleem J. Issaq; Timothy D. Veenstra; Thomas P. Conrads

2004-01-01

344

Vitamin E serum levels in Rett syndrome.  

PubMed

In order to study the role of vitamin E in the pathogenesis of Rett syndrome (RS), we analysed vitamin E serum levels in twenty-eight patients affected by this disorder. We found lower vitamin E serum levels in nine cases (32.1%). These results indicated that the oxidative free radical metabolism may be impaired in a significant percentage of Rett syndrome patients suggesting the need for further studies of tissue vitamin E in different brain regions. PMID:9588862

Formichi, P; Battisti, C; Dotti, M T; Hayek, G; Zappella, M; Federico, A

1998-04-01

345

Serum cytokines in patients with rheumatoid arthritis  

Microsoft Academic Search

Serum cytokines such as interleukin 1ß (IL-1ß), interferon ? (IFN-?), and tumor necrosis factor a (TNFa) were measured in 40 patients with rheumatoid arthritis (RA). In the 40 patients studied, serum IL-1ß was detected in 5 patients, IFN-? in 10 patients, and TNFa in 20 patients. The IL-1ß-positive group showed increased values of activity indices compared to the IL-1ß-negative group.

S. Sakito; Y. Ueki; K. Eguchi; Y. Kawabe; S. Nagataki

1995-01-01

346

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

347

Chemical warfare  

PubMed Central

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

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

2013-01-01

348

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

Microsoft Academic Search

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

Eli Gardiner; Arthur Bums

349

Polymerase chain reaction-based detection of Trypanosoma cruzi DNA in serum.  

PubMed Central

DNAs prepared from chagasic patients' sera were amplified by the polymerase chain reaction using oligonucleotide primers which anneal specifically to a highly repetitive sequence of Trypanosoma cruzi nuclear DNA. Samples from both acutely and chronically infected patients yielded positive results by this method. No significant difference was observed when either whole blood or serum samples of the patients were used. These results indicate that serum instead of whole-blood samples could be used for polymerase chain reaction-based detection of T. cruzi in field studies without the need of applying any special chemical treatment to the specimens. This would represent a considerable advantage due to the easier handling and transportation of serum as compared with whole-blood samples, especially in tropical climates. Images

Russomando, G; Figueredo, A; Almiron, M; Sakamoto, M; Morita, K

1992-01-01

350

Clinical utility of serum sclerostin measurements  

PubMed Central

Sclerostin is an osteocyte-secreted soluble antagonist of the Wnt/?-catenin signaling pathway requisite for osteoblast development and activity. Efforts over the past several years have focused on unraveling the role of sclerostin in both normal physiological and pathological conditions. Sclerostin levels are undetectable in the serum of patients with sclerosteosis. In normal individuals, serum sclerostin levels are higher in males and increase in both sexes across the adult lifespan. Some, but not other, studies have demonstrated that higher serum sclerostin levels are associated with increased fracture risk, particularly when paired with lower bone mineral density. Levels of circulating sclerostin are highly correlated with bone marrow sclerostin levels. Sclerostin levels are inversely related to parathyroid hormone levels. Clinical conditions in which serum sclerostin levels have been measured include ankylosing spondylitis, chronic kidney disease, diabetes, fractures, hypercortisolism, multiple myeloma and spinal cord injury. Even within clearly defined clinical conditions, however, consistent changes in serum sclerostin levels have not always been seen. This may reflect differences in currently available commercial assays or sample sources (serum versus plasma), and suggests further study is needed before sclerostin measurements are introduced into routine clinical practice. Until such issues are resolved, measurement of sclerostin levels appears to be most useful for understanding the mechanisms by which osteocytes regulate bone turnover through the integration of hormonal, physical and pharmacological stimuli, rather than to guide clinical-care decisions.

Clarke, Bart L; Drake, Matthew T

2013-01-01

351

[Serum factors in chronic myeloid leukemia].  

PubMed

Mononuclear cells from the peripheral blood of healthy test persons were cultivated in a methylcellulose medium with serum samples taken from 13 patients with chronic myeloid leukemia (CML) and with osteomyelosclerosis (OMS) as well as with serum samples of 6 healthy test persons. From evaluating the proliferation of granulopoietic cells quantitatively, conclusions were made concerning the concentrations of granulopoietic stimulating substances in these sera. In all cultures with the serum of patients the number of granulopoietic cell colonies was greater than that in cultures with the serum of normal persons. The stronger proliferation of granulopoietic precursor cells in cultures with serum of patients is seen to be due to an enhanced production of the granulocyte-macrophage colony stimulating factor (GM-CSF) by leukemic cells. The differential hemograms and curves indicating the course of leukocytes in patients are compared with the corresponding results of cultures. In patients with CML an increased output of GM-CSF will apparently influence the increase in size of the granulopoietic stem cell pool, which is evident in the steep increase of those curves indicating the course of leukocytes. In patients with OMS, however, there is a discrepancy between granulopoietic serum activity and proliferation in vivo. From these investigations the hypothesis is derived that an increased synthesis of GM-CSF in patients with CML may be one of the causes underlying hyperplastic granulopoiesis. A direct advantage of leukemic cells in proliferation cannot be derived from it.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2419218

Heilmann, E; Eitemöller, H

1985-01-01

352

Serum mercury level and multiple sclerosis.  

PubMed

Exposure to heavy metals has been associated to a higher incidence of multiple sclerosis. In this work, we present a possible relationship between serum mercury levels and development of multiple sclerosis in Isfahan, the third largest city in Iran. Seventy-four patients affected by multiple sclerosis were retrieved from multiple sclerosis (MS) clinic in Isfahan, Iran. By matching sex and age, 74 healthy volunteers were chosen as control group. Blood samples were collected and serum mercury content was determined. Serum mercury level in MS patients was significantly higher than controls (9.6?±?10.17 vs. 5.7?±?8.6, P?=?0.037). Concerning all MS patients, serum mercury value was significantly higher than the mercury concentration founded in control subjects {odd ratio: 2.39 (CI, 1.96-2.94), P?=?0.00}. Serum mercury level is higher in MS patients with odd ratio equal to 2.39 compared with healthy individuals. It may reveal that high mercury levels in serum might help MS development in susceptible individuals. More studies with larger sample size are needed to confirm this hypothesis. PMID:22068727

Attar, Ahmad Movahedian; Kharkhaneh, Azam; Etemadifar, Masoud; Keyhanian, Kiandokht; Davoudi, Vahid; Saadatnia, Mohammad

2012-05-01

353

A study of human serum sickness.  

PubMed

Twelve patients with bone marrow failure, who were undergoing therapy with daily intravenous infusions of horse antithymocyte globulin, were studied for the development of serum sickness. Eleven of 12 patients developed typical signs and symptoms of serum sickness 8-13 days after the initiation of treatment. These included fever, malaise, cutaneous eruptions, arthralgias, gastrointestinal disturbances, and lymphadenopathy. Eleven of 12 patients developed high levels of circulating immune complexes during serum sickness. All 12 patients also had concomitant decreases of serum C3 and C4 levels. In addition to urticarial and/or morbilliform eruptions, 8 of 11 patients also developed a serpiginous band of erythema along the sides of the fingers, hands, toes, or feet as an early cutaneous sign of serum sickness. Direct immunofluorescence of lesional skin biopsies during serum sickness revealed deposits of immunoglobulin or complement in the walls of small cutaneous blood vessels in 3 of 5 patients. These findings indicate that circulating immune complexes play a central role in the pathophysiology of human sickness. PMID:3891879

Lawley, T J; Bielory, L; Gascon, P; Yancey, K B; Young, N S; Frank, M M

1985-07-01

354

Serum Angiotensin Converting Enzyme in Pemphigus Vulgaris  

PubMed Central

Background: Pemphigus vulgaris is an autoimmune blistering skin disease with unknown etiology. Drugs such as angiotensin-converting enzyme (ACE) inhibitors may contribute in the pathogenesis of pemphigus. Objective: We plan this essay to evaluate the serum ACE level in pemphigus vulgaris patients in comparison with healthy controls to recognize its possible role in disease pathogenesis or activity. Methods: This study was planned and performed in the dermatology clinics of Shahid Beheshti University of MedicalSciences’ Hospitals between July 2010 and June 2011. Patients with new onset of pemphigus vulgaris were enrolled in our study. Control subjects were frequency-matched to cases by sex and age. Serum ACE was determined by the spectrophotometric method. Results: Thirty-four patients with pemphigus vulgaris and 35 healthy individuals were recruited in the study. No statistical significant difference was detected in the mean level of serum ACE of the two groups (t-test, P = 0.11). The mean ACE level was significantly lower in male patients compared with male controls (P = 0.04). Moreover, a significant higher serum ACE level of patients with cutaneous involvement was observed compared to patients with mucosal involvement (P = 0.02). Conclusions: Despite lack of any significant difference of serum ACE level between pemphigus and control group, the serum ACE level was considerably lower in male pemphigus vulgaris patients compared with male controls. Therefore, ACE might have some association with pemphigus vulgaris especially in male patients; however, further studies are required to confirm this association.

Robati, Reza M; Ayatollahi, Azin; Toossi, Parviz; Younespour, Shima

2014-01-01

355

Fretting corrosion in saline and serum.  

PubMed

Fretting corrosion of stainless-steel round hole plates and spherical head screws was studied using a simulator that produced a rocking motion of the heads in the plate holes. Experiments were run for 7 days, with the simulator producing 1 oscillation/s for 16 h/day. Fretting corrosion was studied in 0.9% NaCl and in a 10% solution of fetal calf serum in saline. The results showed a tenfold decrease in fretting corrosion when the serum was added to the saline. Measurements of the weight of the two screws and two-hole plate showed those in saline lost 2.9 mg as compared to 0.3 for those in 10% serum. The concentration of nickel in the saline solutions was 12.4 micrograms/mL compared with 0.85 in serum. Visual examination of the solutions and implants revealed that those in saline had a significant amount of corrosion products while those tested in 10% serum were bright and shiny. Recordings of electrical potentials demonstrated that the addition of serum to saline significantly reduced the change in potential from rest to fretting condition. PMID:7276018

Brown, S A; Merritt, K

1981-07-01

356

Inferring serum proteolytic activity from LC-MS/MS data  

PubMed Central

Background In this paper we deal with modeling serum proteolysis process from tandem mass spectrometry data. The parameters of peptide degradation process inferred from LC-MS/MS data correspond directly to the activity of specific enzymes present in the serum samples of patients and healthy donors. Our approach integrate the existing knowledge about peptidases' activity stored in MEROPS database with the efficient procedure for estimation the model parameters. Results Taking into account the inherent stochasticity of the process, the proteolytic activity is modeled with the use of Chemical Master Equation (CME). Assuming the stationarity of the Markov process we calculate the expected values of digested peptides in the model. The parameters are fitted to minimize the discrepancy between those expected values and the peptide activities observed in the MS data. Constrained optimization problem is solved by Levenberg-Marquadt algorithm. Conclusions Our results demonstrates the feasibility and potential of high-level analysis for LC-MS proteomic data. The estimated enzyme activities give insights into the molecular pathology of colorectal cancer. Moreover the developed framework is general and can be applied to study proteolytic activity in different systems.

2012-01-01

357

Serum antioxidant vitamins and risk of cataract.  

PubMed Central

OBJECTIVE--To investigate serum concentrations of alpha tocopherol, beta carotene, retinol, and selenium for their prediction of end stage cataract. DESIGN--A case-control study, nested within a cohort study, based on the linkage of records of subjects aged 40-83 from a health survey with those from the national Finnish hospital discharge register. SUBJECTS--47 patients admitted to ophthalmological wards for senile cataract over 15 years and two controls per patient individually matched for sex, age, and municipality. MAIN OUTCOME MEASURE--Concentration of serum micronutrients, development of cataract according to whether operation was performed. RESULTS--Low serum concentrations of antioxidant vitamins predicted the development of senile cataract, the odds ratio between the lowest third and the two higher thirds of the distribution of serum concentrations of alpha tocopherol and beta carotene being 1.9 (95% confidence interval 0.9 to 4.1) and 1.7 (0.8 to 3.8), respectively. Patients with both alpha tocopherol and beta carotene concentrations in the lowest third had an odds ratio of 2.6 (1.0 to 6.8) of cataract compared with subjects in the top two thirds. The associations were strengthened by adjustment for potential confounding factors such as occupation, smoking, blood pressure, serum cholesterol concentration, body mass index, and diabetes. No association was found between the serum concentrations of selenium, retinol, and retinol binding protein and the risk of cataract. CONCLUSIONS--Low serum concentrations of the antioxidant vitamins alpha tocopherol and beta carotene are risk factors for end stage senile cataract. Controlled trials of the role of antioxidant vitamins in cataract prevention are therefore warranted.

Knekt, P.; Heliovaara, M.; Rissanen, A.; Aromaa, A.; Aaran, R. K.

1992-01-01

358

Early detection of acute renal failure by serum cystatin C  

Microsoft Academic Search

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

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

2004-01-01

359

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.

2011-05-18

360

Interactions of serum with polyelectrolyte-stabilized liposomes: Cryo-TEM studies.  

PubMed

Liposomes are used for in vitro or in vivo vectorization of drugs, proteins, or nucleic acids. However, the main problem with the application of liposomes for this purpose is their low stability in contact with blood serum. In this article, interactions between the whole serum and anionic liposomes, both bare and covered with strong polycations, were studied. The polycations of different chemical structures were prepared by the modification of poly(allylamine hydrochloride) (PAH). Dynamic light scattering (DLS), zeta potential and transmission cryo-electron microscopy (cryo-TEM) measurements showed that the adsorption of the polycations on the anionic liposomes induced a reversible aggregation of vesicles. The stable isolated polyelectrolyte-covered vesicles were obtained after the addition of sufficient amounts of the polycations. The effect of full serum on the morphology and stability of the polycation-coated liposomes was studied using cryo-TEM and a fluorescence method. The cryo-TEM analysis revealed that the introduction of serum caused the osmotic-driven destabilization of the bare liposomes or formation of twinned vesicles. Due to these processes the liposomes lost most of their content immediately after serum addition. The polycation-covered liposomes showed improved stability in the presence of serum. Partial deflation of the vesicles was observed, however, the loss of the content was significantly limited. The effect of the polymer structure, especially the position of the charged groups with respect to the main polymer backbone, on the stabilization of the polycation-covered liposomes in the presence of serum was discussed. PMID:24907584

Wytrwal, Magdalena; Bednar, Jan; Nowakowska, Maria; Wydro, Pawe?; Kepczynski, Mariusz

2014-08-01

361

Determination of silicon in serum and urine by electrothermal atomic absorption spectrometry  

NASA Astrophysics Data System (ADS)

A sensitive, simple and accurate method for the routine determination of trace silicon in serum and urine by Zeeman electrothermal atomic absorption spectrometry is described. The samples are directly determined after 20-fold dilution of serum and 100-fold dilution of urine. No L'vov platform is used. The signal enhancement of silicon atomization in pyrolytic graphite coated graphite tubes is achieved by using a mixture of calcium chloride and lanthanum nitrate as chemical modifier. The interferences arising from the biological matrices have been eliminated by the addition of ammonium dihydrogenphosphate in the sample solutions. The aqueous calibration curve is linear to at least 300 ?g l -1, the characteristic mass is 37 pg (integrated absorbance signal), whereas the detection limit (3SD) is 1.5 ?g l -1 for silicon in both diluted serum and urine samples. The recoveries of silicon added to the diluted samples are 101 ± 1.8% for sera and 98.2 ± 3.5% for the urine specimens, independent of the dilution ratio. The silicon measurement results for the serum and urine from healthy adults and for the serum from the patients with chronic renal failure on hemodialysis are presented.

Huang, Zhuo-er

1995-09-01

362

Problems and progresses in speciation of Al in human serum: an overview.  

PubMed

Aluminium (Al) is associated with many clinical disorders in renal patients. Al accumulation in brain has also been related to the neurodegenerative processes in Alzheimer's disease. In order to better understand Al transport in the human body, it is necessary to identify and quantify chemical species in which Al is present in body fluids and tissues. Among a variety of biological samples, Al speciation was the most frequently investigated in human serum. Improvements were made in the development of analytical techniques for the determination of the amount and composition of high molecular mass Al (HMM-Al) and low molecular mass Al (LMM-Al) species in human serum. However, due to the complex chemistry of Al in serum, its low total concentration and the high risk of contamination, speciation of Al in biological samples is still a difficult task for analytical chemists. In this work, problems related to speciation of Al in human serum are critically discussed. An overview of the progress that was made by the use of different analytical procedures, in order to propose analytical protocols for reliable speciation of Al in serum at low ng mL(-1) concentration range, is presented. PMID:19740542

Milacic, Radmila; Murko, Simona; Scancar, Janez

2009-11-01

363

Chemical spectroscopy  

SciTech Connect

The purpose of chemical spectroscopy with neutrons is to utilize the dependence of neutron scattering cross-sections on isotope and on momentum transfer (which probes the spatial extent of the excitation) to understand fundamental and applied aspects of the dynamics of molecules and fluids. Chemical spectroscopy is divided into three energy ranges: vibrational spectroscopy, 25-500 MeV, for which much of the work is done on Be-filter analyzer instruments; low energy spectroscopy, less than 25 MeV; and high resolution spectroscopy, less than 1 MeV, which typically is performed on backscattering spectrometers. Representative examples of measurements of the Q-depenence of vibrational spectra, higher energy resolution as well as extension of the Q-range to lower values at high energy transfers, and provisions of higher sensitivities in vibrational spectroscopy are discussed. High resolution, high sensitivity, and polarization analysis studies in low energy spectroscopy are discussed. Applications of very high resolution spectroscopy are also discussed. (LEW)

Eckert, J.; Brun, T.O.; Dianoux, A.J.; Howard, J.; Rush, J.J.; White, J.W.

1984-01-01

364

Serum adipokines in inflammatory bowel disease  

PubMed Central

AIM: To investigate serum adipokine levels in inflammatory bowel disease (IBD) patients before treatment and after achieving clinical remission. METHODS: Serum concentrations of six adipokines (tissue growth factor-?1, adiponectin, leptin, chemerin, resistin, and visfatin) were studied in 40 subjects with active IBD [24 subjects with Crohn’s disease (CD) and in 16 subjects with ulcerative colitis (UC)] before and after three months of therapy with corticosteroids and/or azathioprine. Clinical diagnoses were based on ileocolonoscopy, computed tomography or magnetic resonance enterography and histological examination of mucosal biopsies sampled during endoscopy. Serum levels of adipokines were assessed by an indirect enzyme-linked immunosorbent assay. The control group was comprised of 16 age- and sex-matched healthy volunteers. RESULTS: Baseline leptin concentrations were significantly decreased in both types of IBD compared to controls (8.0 ± 9.1 in CD and 8.6 ± 6.3 in UC vs 16.5 ± 10.1 ng/mL in controls; P < 0.05), and significantly increased after treatment only in subjects with CD (14.9 ± 15.1 ng/mL; P < 0.05). Baseline serum resistin concentrations were significantly higher in CD (19.3 ± 12.5 ng/mL; P < 0.05) and UC subjects (23.2 ± 11.0 ng/mL; P < 0.05) than in healthy controls (10.7 ± 1.1 ng/mL). Treatment induced a decrease in the serum resistin concentration only in UC subjects (14.5 ± 4.0 ng/mL; P < 0.05). Baseline serum concentrations of visfatin were significantly higher in subjects with CD (23.2 ± 3.2 ng/mL; P < 0.05) and UC (18.8 ± 5.3 ng/mL; P < 0.05) than in healthy controls (14.1 ± 5.3 ng/mL). Treatment induced a decrease in the serum visfatin concentrations only in CD subjects (20.4 ± 4.8 ng/mL; P < 0.05). Serum levels of adiponectin, chemerin and tissue growth factor-?1 did not differ between CD and UC subjects compared to healthy controls and also were not altered by anti-inflammatory therapy. Clinical indices of IBD activity did not correlate with adipokine levels. CONCLUSION: IBD modulates serum adipokine levels by increasing resistin and visfatin release and suppressing leptin production.

Waluga, Marek; Hartleb, Marek; Boryczka, Grzegorz; Kukla, Michal; Zwirska-Korczala, Krystyna

2014-01-01

365

Changes of serum angiogenic biomarkers and their correlations with serum leptin concentration.  

PubMed

Aim: Obesity is considered as a major health problem. Angiogenic vessels by providing oxygen, nutrients and growth factors trigger growth and survival signals in adipocytes. We aimed to investigate the effect of high-fat diet (HFD) on serum angiogenic biomarkers including vascular endothelial growth factor (VEGF), soluble VEGF receptor 1 (sVEGFR1), nitric oxide (NO) concentrations and their correlations with serum leptin level in obese and control groups.Methods: Twenty male C57BL/6 mice were randomly assigned into the control and obese groups. Obese group received HFD for 15 weeks. At the end of experiment, blood samples were collected for blood glucose, serum insulin, VEGF, sVEGFR1, NO and leptin level measurements and correlation between serum angiogenic factors and leptin levels were analyzed.Results: HFD induced higher serum NO and leptin levels compared to the control group, while, it did not affect serum VEGF and sVEGFR1 concentrations. There was a strong positive correlation between serum leptin and NO levels (r=0.78), however, a weak correlation was found between serum leptin and VEGF and VEGFR-1 concentrations.Conclusion: It seems that the angiogenic activities in obese mice are through the mechanisms that were not regulated by VEGF or VEGF receptors rather; other factors such as leptin and NO are involved (Tab. 1, Fig. 4, Ref. 32). PMID:25023421

Tahergorabi, Z; Khazaei, M

2014-01-01

366

Association Between Serum Soluble CD30 and Serum Creatinine Before and After Renal Transplantation  

Microsoft Academic Search

ObjectiveThere is increasing evidence that circulating levels of soluble CD30 (sCD30) may represent a biomarker for outcome in kidney transplantation. The aim of this study was to measure the pre- and posttransplantation serum levels of sCD30 in cadaveric kidney transplant recipients and correlate them with serum creatinine.

M. López-Hoyos; D. San Segundo; M. J. Benito; G. Fernández-Fresnedo; J. C. Ruiz; E. Rodrigo; C. Gómez-Alamillo; A. Benito; M. Arias

2008-01-01

367

Early In vitro Lipopolysaccharide-Induced Serum Protein Aggregation in Tolerant Serum.  

National Technical Information Service (NTIS)

In a rat LPS shock model, an intravenous injection of LPS (3 - 30 mg/kg body weight) corresponds to an estimated peak load of 0.13-1.3 mg LPS/ml serum. We tested the effects of such LPS concentrations in vitro. Rat serum was incubated with LPS (0.1 - 2.0 ...

M. A. Fletcher T. K. Morrison T. J. Williams

1992-01-01

368

Peptidomic Identification of Serum Peptides Diagnosing Preeclampsia  

PubMed Central

We sought to identify serological markers capable of diagnosing preeclampsia (PE). We performed serum peptide analysis (liquid chromatography mass spectrometry) of 62 unique samples from 31 PE patients and 31 healthy pregnant controls, with two-thirds used as a training set and the other third as a testing set. Differential serum peptide profiling identified 52 significant serum peptides, and a 19-peptide panel collectively discriminating PE in training sets (n?=?21 PE, n?=?21 control; specificity?=?85.7% and sensitivity?=?100%) and testing sets (n?=?10 PE, n?=?10 control; specificity?=?80% and sensitivity?=?100%). The panel peptides were derived from 6 different protein precursors: 13 from fibrinogen alpha (FGA), 1 from alpha-1-antitrypsin (A1AT), 1 from apolipoprotein L1 (APO-L1), 1 from inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4), 2 from kininogen-1 (KNG1), and 1 from thymosin beta-4 (TMSB4). We concluded that serum peptides can accurately discriminate active PE. Measurement of a 19-peptide panel could be performed quickly and in a quantitative mass spectrometric platform available in clinical laboratories. This serum peptide panel quantification could provide clinical utility in predicting PE or differential diagnosis of PE from confounding chronic hypertension.

Wu, Shuaibin; Stevenson, David K.; Sheng, Guojun; Butte, Atul J.; Ling, Xuefeng B.

2013-01-01

369

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

370

Serum carnitine concentrations in coeliac disease.  

PubMed Central

Carnitine is essential for muscle energy production and is required for the transport of long chain fatty acids and acyl co-enzyme A derivatives across the inner mitochondrial membrane. Recently, an absorptive transport mechanism was discovered at the small bowel level suggesting the possibility of a carnitine deficient state in patients with mucosal damage. Therefore, this study investigated carnitine concentrations in serum of patients with coeliac disease. Serum samples were obtained from 12 patients with active coeliac disease and seven with non-active disease, and compared with serum samples of 17 children with gastrointestinal symptoms but with a small bowel normal on biopsy examination and 33 normal controls. Total serum carnitine concentration was significantly lower in the patients with coeliac disease compared with the other two groups and to reference values. When the degree of atrophy of coeliac intestinal mucosa was numerically graded, serum carnitine concentrations did not correlate to the degree of the intestinal lesion but were significantly lower in the damaged intestine compared with the group with normal mucosa. It is suggested that coeliac disease should be considered as a potential cause of secondary carnitine deficiency.

Lerner, A; Gruener, N; Iancu, T C

1993-01-01

371

Proteomic evaluation of sheep serum proteins  

PubMed Central

Background The applications of proteomic strategies to ovine medicine remain limited. The definition of serum proteome may be a good tool to identify useful protein biomarkers for recognising sub-clinical conditions and overt disease in sheep. Findings from bovine species are often directly translated for use in ovine medicine. In order to characterize normal protein patterns and improve knowledge of molecular species-specific characteristics, we generated a two-dimensional reference map of sheep serum. The possible application of this approach was tested by analysing serum protein patterns in ewes with mild broncho-pulmonary disease, which is very common in sheep and in the peripartum period which is a stressful time, with a high incidence of infectious and parasitic diseases. Results This study generated the first reference 2-DE maps of sheep serum. Overall, 250 protein spots were analyzed, and 138 identified. Compared with healthy sheep, serum protein profiles of animals with rhino-tracheo-bronchitis showed a significant decrease in protein spots identified as transthyretin, apolipoprotein A1 and a significant increase in spots identified as haptoglobin, endopin 1b and alpha1B glycoprotein. In the peripartum period, haptoglobin, alpha-1-acid glycoprotein, apolipoprotein A1 levels rose, while transthyretin content dropped. Conclusions This study describes applications of proteomics in putative biomarker discovery for early diagnosis as well as for monitoring the physiological and metabolic situations critical for ovine welfare.

2012-01-01

372

Crocodylus siamensis serum and macrophage phagocytic activity.  

PubMed

Antimicrobial activity of sera from many crocodilian species has been recognized. This activity was proposed to be mediated, at least in part, by complement. Due to the fact that complement proteins have different functions in the immune system, they may be involved in phagocytic process of phagocytes. In the present study, the effects of Siamese crocodile serum on phagocytic activity of macrophages as well as the possible involvement of complement in this process were examined. The results showed increases in the phagocytosis of both Escherichia coli and to a lesser extent, Staphylococcus aureus upon incubation of murine macrophage cell line with fresh crocodile serum (FS). Similar to FS, other crocodile blood products, including freeze dried serum (DS) and freeze dried whole blood (DWB) exhibited phagocytosis-enhancing property. However the ability of DWB to enhance phagocytosis was less efficient than that of FS and DS, suggesting that serum factors were involved in this process. Treatment of FS with heat at 56 degrees C for 30 min deteriorated the effect of FS on bacterial uptake of macrophages, suggesting that complement proteins play a role in the modulation of the phagocytic process. Collectively, the results of the present study suggested that crocodile serum enhances the macrophage phagocytic activity through complement activity and, therefore, may be taken as an alternative medicine for supporting the human immune responses. PMID:22619919

Aree, Kalaya; Siruntawineti, Jindawan; Chaeychomsri, Win

2011-12-01

373

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

374

Cancer marker detection in human serum with a point-of-care low-cost system  

Microsoft Academic Search

Chemiluminescence, i.e. the emission of light from a chemical reaction, offers interesting opportunities for developing point-of-care biosensors. However, commercially available systems are expensive, bulky, and primarily addressed to laboratory usage. The goal of this paper is to present a novel work related to the design and experimental validation of a point-of-care device for cancer marker detection in human serum. The

Pasquale Grosso; Sandro Carrara; Claudio Stagni; Luca Benini

2010-01-01

375

Microdetermination of human serum albumin by differential pulse voltammetry at a l -cysteine modified silver electrode  

Microsoft Academic Search

A simple and highly sensitive electrochemical method for the determination of human serum albumin (HSA) using differential\\u000a pulse voltammetry (DPV), based on a silver electrode modified with a self-assembled monolayer of l-cysteine, was developed. l-cysteine can be modified onto a silver electrode by covalent bonding through the sulfur to give stable and long-lived chemical\\u000a electrodes. This electrode showed good sensitivity,

Liyuan Lu; Yanqin Zi; Hongling Wang

2008-01-01

376

Effect of serum proteins on polystyrene nanoparticle uptake and intracellular trafficking in endothelial cells  

Microsoft Academic Search

The physico-chemical properties of nanoparticles (NPs), such as small dimensions, surface charge and surface functionalization,\\u000a control their capability to interact with cells and, in particular, with sub-cellular components. This interaction can be\\u000a also influenced by the adsorption of molecules present in biological fluids, like blood, on NP surface. Here, we analysed\\u000a the effect of serum proteins on 49 and 100 nm

Daniela Guarnieri; Angela Guaccio; Sabato Fusco; Paolo A. Netti

377

Materials Indistinguishable from Iodotyrosines in Normal Human Serum and Human Serum Albumin*  

PubMed Central

Materials indistinguishable from authentic mono- and diiodotyrosines were identified in extracts of normal human serum as well as in extracts of purified human serum albumin. These materials were not found in association with the other serum proteins. Identification of MIT and DIT was made by a technique using rechromatography to constant specific activity, as well as by the Barker wet ash distillation method, which established the compounds in question as being iodinated ones. By two different extraction and chromatographic methods we estimated the amounts of both MIT and DIT present in normal human serum or albumin; the estimates were in good agreement. These compounds together constituted between 19% and 25% of the extractable serum iodine. Images

Weinert, Henry; Masui, Hideo; Radichevich, Ildiko; Werner, Sidney C.

1967-01-01

378

Materials indistinguishable from iodotyrosines in normal human serum and human serum albumin.  

PubMed

Materials indistinguishable from authentic mono- and diiodotyrosines were identified in extracts of normal human serum as well as in extracts of purified human serum albumin. These materials were not found in association with the other serum proteins. Identification of MIT and DIT was made by a technique using rechromatography to constant specific activity, as well as by the Barker wet ash distillation method, which established the compounds in question as being iodinated ones. By two different extraction and chromatographic methods we estimated the amounts of both MIT and DIT present in normal human serum or albumin; the estimates were in good agreement. These compounds together constituted between 19% and 25% of the extractable serum iodine. PMID:6027088

Weinert, H; Masui, H; Radichevich, I; Werner, S C

1967-07-01

379

NEUTRALIZATION OF VIRUSES BY HOMOLOGOUS IMMUNE SERUM  

PubMed Central

Neutralization experiments with Newcastle disease, influenza A, or bacterial virus, T3, reveal, under all conditions studied, a linear relationship between the logarithm of the serum dilution end point and that of the quantity of virus used. With Newcastle disease and influenza A, the slope of the neutralization line varies markedly with the host-cell system used and in the chick embryo is strikingly affected by the route of inoculation. The other variables examined have no definite effect upon the slope. Reactivation of neutralized influenza virus is demonstrable in the chick embryo on dilution of the mixture. There appears to be an inverse relationship between the degree of susceptibility of a host to infection with influenza A virus and the neutralizing titer of a serum as measured in that host. With the T3-serum system, comparable results are obtained when the number of unneutralized virus particles chosen as the end point is varied widely.

Tyrrell, David A. J.; Horsfall, Frank L.

1953-01-01

380

Serum adenosine deaminase activity in cutaneous anthrax  

PubMed Central

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

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

2014-01-01

381

SERUM FERMENTS AND ANTIFERMENT DURING TRYPSIN SHOCK  

PubMed Central

1. The intravenous injection of trypsin in dogs results in a shock similar in many respects to anaphylactic and peptone shock. 2. The injection is followed by a marked rise of serum protease and lipase. 3. The antiferment usually shows a distinct drop in titer, with a recovery following in from four to twenty-four hours. 4. The non-coagulable nitrogen shows no constant alteration, but is never greatly changed in amount. 5. Inactivated preparations were in some respects followed by symptoms similar to those following the injection of the active preparation. 6. Subcutaneous and gastric absorption was practically without effect. 7. Intestinal absorption was followed by an increase in serum protease without evidence of intoxication, or by typical symptoms of acute poisoning. 8. The leucocyte curve bears no constant relation to the serum protease or lipase.

Jobling, James W.; Petersen, William; Eggstein, A. A.

1915-01-01

382

Serum adenosine deaminase activity in cutaneous anthrax.  

PubMed

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

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

2014-01-01

383

Chemical Analyses  

NASA Technical Reports Server (NTRS)

As a preliminary study on the effects of chemical aging of polymer materials MERL and TRI have examined two polymeric materials that are typically used for offshore umbilical applications. These two materials were Tefzel, a copolymer of ethylene and tetrafluoroethylene, and Coflon, polyvinylidene fluoride. The Coflon specimens were cut from pipe sections and exposed to H2S at various temperatures and pressures. One of these specimens was tested for methane permeation, and another for H2S permeation. The Tefzel specimens were cut from .05 mm sheet stock material and were exposed to methanol at elevated temperature and pressure. One of these specimens was exposed to methanol permeation for 2 days at 100 C and 2500 psi. An additional specimen was exposed to liquid methanol for 3 days at 150 C and 15 Bar. Virgin specimens of each material were similarly prepared and tested.

Bulluck, J. W.; Rushing, R. A.

1994-01-01

384

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

385

Relationship of Serum HER2\\/neu and Serum CA 15-3 in Patients with Metastatic Breast Cancer  

Microsoft Academic Search

Background: Serum HER-2\\/neu antigen concentrations have been reported to correlate with increased tumor volume in patients with breast cancer. We measured serum CA 15-3, a surrogate marker of disease burden, and correlated serum CA 15-3 with serum HER-2\\/neu and analyzed the association of both markers with clinical outcomes. Methods: Pretreatment serum samples from 566 patients were retrospectively analyzed from 2

Suhail M. Ali; Kim Leitzel; Vernon M. Chinchilli; Linda Engle; Laurence Demers; Harold A. Harvey; Walter Carney; Jeffrey W. Allard; Allan Lipton

386

The effect of glucagon on serum gastrin  

PubMed Central

Serum gastrin was measured by radioimmunoassay in four patients with pernicious anaemia and four patients with the Zollinger-Ellison syndrome before and after the intravenous injection of 1 mg glucagon. Serum gastrin fell significantly in the patients with pernicious anaemia whilst in the patients with the Zollinger-Ellison syndrome there was a significant rise. Concomitant measurement of gastric acid output in one subject with the Zollinger-Ellison syndrome also showed a rise in acid output with glucagon. The reason for the paradoxical rise in gastrin in response to glucagon in the Zollinger-Ellison syndrome is unknown, but the response may provide a further diagnostic aid to this condition.

Korman, M. G.; Soveny, C.; Hansky, J.

1973-01-01

387

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

388

Digoxin concentrations in serum and saliva  

PubMed Central

1 After 1 week of baseline observations increasing oral doses of digoxin were administered to four healthy volunteers over a 6-7 week period. 2 A dose-response relationship exists with regards to PTQ-changes (a quantitative measure of ECG-changes). 3 PTQ-changes were related linearly to both serum and salivary digoxin levels. 4 PTQ-changes appear to be useful as a non-invasive measure for studying various aspects of digoxin pharmacodynamics. 5 Serial salivary digoxin levels might be a better index of the effect of cardiac glycosides than individual or serial serum levels.

Joubert, P. H.; Aucamp, B. N.; Muller, F. O.

1976-01-01

389

Immunogenicity of Acrylate Chemicals as Assessed by Antibody Induction  

Microsoft Academic Search

The immunogenicities of two acrylate chemicals, trimethylolpropane triacrylate (TMPTA) and methyl acrylate (MeAc), and one related vinyl compound, 4-vinyl pyridine (4VP), were investigated by determining the in vivo induction of IgG antibodies in guinea pigs. The injection of the chemicals emulsified in Freund’s complete adjuvant resulted in the induction of serum antibody responses against MeAc and 4VP but not TMPTA.

J. E. Bull; D. C. Henderson; J. L. Turk

1987-01-01

390

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.

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

2014-01-01

391

Association between serum levels of carotenoids and serum asymmetric dimethylarginine levels in Japanese subjects.  

PubMed

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

2014-05-01

392

Physico-chemical properties of South American iguanid albumins.  

PubMed

Except for a markedly reduced anodal electrophoretic mobility, the serum of the Galapagos marine iguana was physico-chemically identical to that of terrestrial iguanids. Reduction in albumin net charge may have facilitated the adaptation of this species to a semi-aquatic environment. PMID:7193598

Higgins, P J

1980-12-15

393

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

394

Cooperative binding of drugs on human serum albumin  

NASA Astrophysics Data System (ADS)

In order to explain the adsorption isotherms of the amphiphilic penicillins nafcillin and cloxacillin onto human serum albumin (HSA), a cooperative multilayer adsorption model is introduced, combining the Brunauer-Emmet-Teller (BET) adsorption isotherm with an amphiphilic ionic adsorbate, whose chemical potential is derived from Guggenheim's theory. The non-cooperative model has been previously proved to qualitatively predict the measured adsorption maxima of these drugs [Varela, L. M., García, M., Pérez-Rodríguez, M., Taboada, P., Ruso, J. M., and Mosquera, V., 2001, J. chem. Phys., 114, 7682]. The surface interactions among adsorbed drug molecules are modelled in a mean-field fashion, so the chemical potential of the adsorbate is assumed to include a term proportional to the surface coverage, the constant of proportionality being the lateral interaction energy between bound molecules. The interaction energies obtained from the empirical binding isotherms are of the order of tenths of the thermal energy, therefore suggesting the principal role of van der Waals forces in the binding process.

Varela, L. M.; Pérez-Rodríguez, M.; García, M.

395

Fluvoxamine increases the clozapine serum levels significantly  

Microsoft Academic Search

In this case report we describe an interaction between clozapine and fluvoxamine in two physically healthy patients meeting the DSM-IIIR criteria for paranoid schizophrenia. The substantial rise of clozapine serum levels suggest that caution should be exercised when combining fluvoxamine with clozapine as the clozapine concentration may increase by a factor of 5–10.

Hannu J. Koponen; Esa Leinonen; Ulla Lepola

1996-01-01

396

Serum tube identification of Candida albicans  

Microsoft Academic Search

The production of filaments (germ tubes) by cells of Candida albicans in serum tubes permits presumptive identification to be made within two to three hours. The proportion of yeast-like cells forming filaments is progressively decreased with increasing cell concentration. The test is effective over a comparatively wide range of temperatures and using different types and concentrations of sera.

D. W. R. Mackenzie

1962-01-01

397

Molecular Serum Markers of Liver Fibrosis  

PubMed Central

Fibrosis is a hallmark histologic event of chronic liver diseases and is characterized by the excessive accumulation and reorganization of the extracellular matrix (ECM). The gold standard for assessment of fibrosis is liver biopsy. As this procedure has various limitations, including risk of patient injury and sampling error, a non-invasive serum marker for liver fibrosis is desirable. The increasing understanding of the pathogenesis of hepatic fibrosis has suggested several markers which could be useful indicators of hepatic fibrogenesis and fibrosis. These markers include serum markers of liver function, ECM synthesis, fibrolytic processes, ECM degradation and fibrogenesis related cytokines. Recently, neo-epitopes, which are post-translational modifications of proteins, have been successfully used in bone and cartilage diseases which are characterized by extensive ECM remodeling. Increasing numbers of studies are being undertaken to identify neo-epitopes generated during liver fibrosis, and which ultimately might be useful for diagnosing and monitoring fibrogenesis. To date, the metalloproteinases generated fragment of collagen I, III, IV and VI have been proven to be elevated in two rat models of fibrosis. This review summarizes the recent efforts that have been made to identify potentially reliable non-invasive serum markers. We used the recently proposed BIPED (Burden of disease, Investigative, Prognostic, Efficacy and Diagnostic) system to characterize potential serum markers and neo-epitope markers that have been identified to date.

Liu, Tianhui; Wang, Xiaoming; Karsdal, Morten A.; Leeming, Diana J.; Genovese, Federica

2012-01-01

398

Total and Free Triiodothyronine in Human Serum*  

PubMed Central

A reliable method has been developed for the determination of total serum T3, dialyzable fraction (DFT3), and absolute concentration of free T3 (AFT3). Total T3 values (mean ± SD) were: healthy euthyroid subjects, 0.33 ± 0.07 ?g per 100 ml; hyperthyroid patients, 0.71 ± 0.1 ?g per 100 ml; hypothyroid, 0.10 ± 0.03 ?g per 100 ml. Values (mean ± SD) for DFT3 in these groups were 0.46 ± 0.14%, 0.78 ± 0.17%, and 0.16 ± 0.08%, respectively. Calculated values for AFT3 were: 1.51 ± 0.4 m?g per 100 ml, 5.00 ± 0.6 m?g per 100 ml and 0.24 ± 0.1 m?g per 100 ml, respectively. Dilution of serum before dialysis lowered estimated DFT3 values. Enrichment of serum with labeled T3 in the range examined did not affect DFT3. However, DFT3 was increased by addition of Merthiolate to serum in concentration 1: 10,000 due to displacement of T3 from thyroxine-binding globulin to albumin. The data suggest that triiodothyronine may play a considerably more important role in normal and pathological physiology, as evidenced by kinetic analysis using these data. A metabolic role for T3 equal to that of T4 is indicated. Images

Nauman, Janusz A.; Nauman, Alicja; Werner, Sidney C.

1967-01-01

399

Serum creatine kinase levels in normal females  

Microsoft Academic Search

Serum creatine kinase levels were determined in 75 girls (age range, one month to 15 years) and 200 normal adult women (age range, 18 to 50 years). The values ranged from 12.5 to 80 IU\\/1 in girls and 19 to 155 IU\\/1 in adult females. The SCK level appeared to increase with age from 1 to 15 years, after which

R K Satapathy; R Skinner

1979-01-01

400

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

401

Dietary phosphorus, serum phosphorus, and cardiovascular disease.  

PubMed

Recent epidemiologic studies have linked higher serum phosphorus concentrations to cardiovascular disease (CVD) events and mortality. This association has been identified in the general population and in those with chronic kidney disease (CKD). The risk of adverse outcomes appears to begin with phosphorus concentrations within the upper limit of the normal reference range. Multiple experimental studies have suggested pathogenetic mechanisms that involve direct and indirect effects of high phosphorus concentrations to explain these associations. Drawing from these observations, guideline-forming agencies have recommended that serum phosphorus concentrations be maintained within the normal reference range in patients with CKD and that dietary phosphorus restriction or use of intestinal phosphate binders should be considered to achieve this goal. However, outside the dialysis population, the links between dietary phosphorus intake and serum phosphorus concentrations, and dietary phosphorus intake and CVD events, are uncertain. With specific reference to the nondialysis populations, this review discusses the available data linking dietary phosphorus intake with serum phosphorus concentrations and CVD events. PMID:24117725

Menon, Madhav C; Ix, Joachim H

2013-10-01

402

Serum PDGF-AB in Pleural Mesothelioma  

Microsoft Academic Search

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

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

2005-01-01

403

Serum prolactin levels in psoriasis vulgaris.  

PubMed

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

404

Serum Fibrin Degradation Products Throughout Normal Pregnancy  

Microsoft Academic Search

Fibrin\\/fibrinogen degradation products in the serum of 169 healthy pregnant and 43 healthy non-pregnant subjects of a similar age group showed a significant increase throughout pregnancy, the highest levels being obtained in the third trimester. There was no correlation with plasma fibrinogen levels or euglobulin lysis times. Though these changes may be due to other alterations in pregnancy not primarily

D. G. Woodfield; S. K. Cole; A. G. E. Allan; J. D. Cash

1968-01-01

405

Inactivation of Anthracyclines by Serum Heme Proteins  

Microsoft Academic Search

We have previously shown that the anticancer agent doxorubicin undergoes oxidation and inactivation when exposed to myeloperoxidase-containing human leukemia HL-60 cells, or to isolated myeloperoxidase, in the presence of hydrogen peroxide and nitrite. In the current study we report that commercial fetal bovine serum (FBS) alone oxidizes doxorubicin in the presence of hydrogen peroxide and that nitrite accelerates this oxidation.

Brett A. Wagner; Lynn M. Teesch; Garry R. Buettner; Bradley E. Britigan; C. Patrick Burns; Krzysztof J. Reszka

2007-01-01

406

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.

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

2014-01-01

407

Biomarker Amplification by Serum Carrier Protein Binding  

PubMed Central

Mass spectroscopic analysis of the low molecular mass (LMM) range of the serum/plasma proteome is a rapidly emerging frontier for biomarker discovery. This study examined the proportion of LMM biomarkers, which are bound to circulating carrier proteins. Mass spectroscopic analysis of human serum following molecular mass fractionation, demonstrated that the majority of LMM biomarkers exist bound to carrier proteins. Moreover, the pattern of LMM biomarkers bound specifically to albumin is distinct from those bound to non-albumin carriers. Prominent SELDI-TOF ionic species (m/z 6631.7043) identified to correlate with the presence of ovarian cancer were amplified by albumin capture. Several insights emerged: a) Accumulation of LMM biomarkers on circulating carrier proteins greatly amplifies the total serum/plasma concentration of the measurable biomarker, b) The total serum/plasma biomarker concentration is largely determined by the carrier protein clearance rate, not the unbound biomarker clearance rate itself, and c) Examination of the LMM species bound to a specific carrier protein may contain important diagnostic information. These findings shift the focus of biomarker detection to the carrier protein and its biomarker content.

Mehta, Arpita I.; Ross, Sally; Lowenthal, Mark S.; Fusaro, Vincent; Fishman, David A.; Petricoin, Emanuel F.; Liotta, Lance A.

2003-01-01

408

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...

409

Exposure to Hexabromocyclododecanes (HBCDs) via Dust Ingestion, but Not Diet, Correlates with Concentrations in Human Serum: Preliminary Results  

PubMed Central

Background Hexabromocyclododecane (HBCD) is a high-production-volume chemical used as flame retardant in polystyrene insulation and textiles. Because it is not chemically bound to the polymer, HBCD can migrate into the environment, contaminating indoor dust and foodstuff. Objectives We examined for the first time the relationship between combined exposure to three HBCD isomers (?HBCDs) via ingestion of food (duplicate diets) and indoor dust and HBCD concentrations in serum for 16 Belgian adults (20–25 years of age). We also determined the chiral signatures of HBCDs to advance understanding of source-to-human enantioselective degradation and/or metabolism. Methods Concentrations and chiral signatures of ?-, ?-, and ?-HBCD in duplicate diets, dust, and serum were measured by liquid chromatography/tandem mass spectrometry. Results Dietary intakes of ?HBCDs were 1.2–20 ng/day (average, 7.2 ng/day), whereas those estimated under average (20 mg dust/day) and high (50 mg dust/day) dust ingestion scenarios were 1.1–15 ng/day (average intake, 3.2 ng/day) and 2.8–38 ng/day (average intake, 8.0 ng/day), respectively. Concentrations of ?HBCDs measured in blood serum were < 0.5 to 11 ng/g lipid weight (lw) (average, 2.9 ng/g lw). ?-HBCD dominated in food, whereas ?-HBCD dominated in dust and was the sole isomer in serum. Although exposure via dust ingestion correlated significantly (p < 0.01) with concentrations in serum, no such correlation was evident with dietary exposure (p > 0.1). Although no enantioselective enrichment was detected in either dust or diet, substantial enrichment of (?)?-HBCD was observed in serum. Conclusions Serum concentrations of HBCDs were correlated with the exposure via dust, but not via dietary ingestion. The enrichment of the (?)?-HBCD enantiomer in humans appears to be due to in vivo enantioselective metabolism/excretion rather than ingestion of dust or diet.

Roosens, Laurence; Abdallah, Mohamed Abou-Elwafa; Harrad, Stuart; Neels, Hugo; Covaci, Adrian

2009-01-01

410

Proteomic expression profiling and identification of serum proteins using immobilized trypsin beads with MALDI-TOF/TOF.  

PubMed

MALDI-TOF mass spectrometry is a widely used technique for serum protein expression profiling and biomarker discovery. Many profiling strategies typically employ chemical affinity beads or surfaces to decrease sample complexity of dynamic fluids such as serum or plasma. However, many of the proteins captured on a particular surface or bead are not resolved in the lower mass ranges where time-of-flight mass spectrometers are most effective. Thus, a majority of reported protein expression profiling studies primarily interrogate the native low molecular mass constituents of the target sample. We report an expression profiling workflow that utilizes immobilized trypsin paramagnetic beads following an initial affinity bead fractionation step, thereby reducing large mass proteins to peptides that are better suited to analysis and sequencing determinations. Our bead-based trypsin approach resulted in more efficient digestion of complex