The estimation of total serum lipids by a completely enzymatic ‘summation’ method

Akins, James R.; Waldrep, Kay; Bernert, John T.

doi:10.1016/0009-8981(89)90054-5

Cited by 219 publications

(141 citation statements)

References 18 publications

Supporting

Mentioning

141

Contrasting

Order By: Relevance

“…Sample sizes were as follows: triglycerides (2 μL), total cholesterol (2 μL), non-esterified (free) cholesterol (50 μL), and phospholipids (20 μL). Total lipid concentrations were estimated using the summation method of Akins et al (1989). The total lipid content was expressed in g L −1 .…”

Section: Sample Collectionmentioning

confidence: 99%

Can polychlorinated biphenyl (PCB) signatures and enantiomer fractions be used for source identification and to age date occupational exposure?

Megson

Focant

Patterson

et al. 2015

Environment International

View full text Add to dashboard Cite

Detailed polychlorinated biphenyl (PCB) signatures and chiral Enantiomer Fractions (EFs) of CB-95, CB-136 and CB-149 were measured for 30 workers at a transformer dismantling plant. This was undertaken to identify sources of exposure and investigate changes to the PCB signature and EFs over different exposure periods. Approximately 1.5 g of serum was extracted and PCB signatures were created through analysis by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC × GC-TOFMS) and EFs calculated following analysis by gas chromatography with high resolution mass spectrometry (GC-HRMS). A total of 84 PCBs were identified in the serum samples with concentrations of the 7 indicator PCBs ranging from 11-350 ng g −1 of serum (1.2-39 μg g −1 lipid). The PCB signatures were interpreted using principal component analysis (PCA) which was able to distinguish workers with background or recent minimal exposure from those with prolonged occupational exposure. Occupationally exposed individuals had a similar PCB profile to Aroclor A1260. However, individuals with prolonged exposure had depleted proportions of several PCB congeners that are susceptible to metabolism (CB-95, CB-101 and CB-151) and elevated proportions of PCBs that are resistant to metabolism (CB-74, CB-153, CB-138 and CB-180). The results also identified a third group of workers with elevated proportions of CB-28, CB-60, CB-66, CB-74, CB-105 and CB-118 who appeared to have been exposed to an additional source of PCBs. The results show near complete removal of the CB-95 E2 enantiomer in some samples, indicating that bioselective metabolism or preferential excretion of one enantiomer occurs in humans. By considering PCB concentrations along with detailed congener specific signatures it was possible to identify different exposure sources, and gain an insight into both the magnitude and duration of exposure.

show abstract

Section: Sample Collectionmentioning

confidence: 99%

Can polychlorinated biphenyl (PCB) signatures and enantiomer fractions be used for source identification and to age date occupational exposure?

Megson

Focant

Patterson

et al. 2015

Environment International

View full text Add to dashboard Cite

show abstract

“…In addition, 36 PCBs were measured including the mono-ortho PCBs (PCB 105,118,156,157,167). Serum total lipids were calculated using an enzymatic 'summation' method (Akins et al, 1989). Values were reported on a lipid-weight basis in ppt for PCDDs, PCDFs, and coplanar PCBs, and parts per billion (ppb) for the 36 non-coplanar PCBs.…”

Section: Hrgc/hrms Chemical Analysismentioning

confidence: 99%

Dioxin-Like TEQ of women from the Seveso, Italy area by ID-HRGC/HRMS and CALUX

Warner¹,

Eskenazi²,

Patterson

et al. 2004

J Expo Sci Environ Epidemiol

View full text Add to dashboard Cite

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) are widespread environmental contaminants that exist as complex mixtures and are frequently detected at part-per-trillion (ppt) levels in humans. Using isotope dilution high-resolution gas chromatography/ high-resolution mass spectrometry (HRGC/HRMS), we measure the PCDDs, PCDFs, and PCBs in serum of a population of 78 women residing in an area near Seveso, Italy where a TCDD explosion occurred in 1976 and where furniture is manufactured. The average total dioxin-like toxic equivalents (TEQ) of these women was 25.3 ppt, lipid-adjusted, comparable to other parts of Europe. TCDD levels, however, were higher among the few women who resided in the exposed area in 1976. We examined the possibility of using the CALUX (chemicalactivated luciferase gene expression) bioassay to estimate total TEQ in a small volume of plasma from this population. A total of 32 archived plasma specimens were selected for CALUX bioassay, based on the distribution of Total TEQ by HRGC/HRMS. The CALUX bioassay was performed blind to HRGC/HRMS results with 2 ml plasma per replicate analysis. Of 32 samples, 10 were below detection limits in the CALUX bioassay. For the 32 samples, the CALUX-TEQ averaged 25.4 ppt, lipid-adjusted (range: 0-127.6) and was not significantly different from the HRGC/HRMS Total TEQ average of 31.2 ppt, lipid-adjusted (range: 12.7-88.3) (t ¼ 0.88, P ¼ 0.38), however, the two measures were not significantly correlated (R s ¼ 0.04, P ¼ 0.82). More validation of the CALUX bioassay with larger sample volume is needed before application as an exposure measure in large-scale epidemiologic studies of health effects of dioxin-like compounds.

show abstract

“…Briefly, 2 ml of plasma sample was acidified, then [13C]-labeled internal standard mixture and a surrogate standard (3-MeSO 2 -4-Me-2 0 ,3 0 ,4 0 ,5,5 0 -PentaCB) for the MeSO 2 -PCBs were added, and extraction was performed using a solid-phase extraction column (OASIS HLB, Waters). Lipid content (%, w/w) was determined enzymatically for plasma samples, and total amounts of lipids were calculated according to the following equation: TL ¼ 1.677 Â (TC -FC) þ FC þ TG þ PL where TL ¼ total lipids, TC ¼ total cholesterol, FC ¼ cholesterol, TG ¼ triacylglycerol, and PL ¼ phospholipids [22].…”

Section: Chemical Analysismentioning

confidence: 99%

Effect of reduced food intake on toxicokinetics of halogenated organic contaminants in herring gull (Larus argentatus) chicks

Routti

Helgason

Arukwe

et al. 2012

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

Abstract-The aim of the present study was to investigate how contaminant exposure and reduced food intake affect tissue distribution and biotransformation of halogenated organic contaminants (HOCs) in Arctic seabirds using herring gull (Larus argentatus) as a model species. Herring gull chicks were exposed for 44 d to cod liver oil containing a typical mixture of contaminants. Following exposure, food intake was reduced for a one-week period in a subgroup of the chicks. Polyclorinated biphenyls, organochlorine pesticides, and brominated flame retardants, as well as a wide range of hydroxy, methyl sulfone, and methoxy compounds were measured in liver, brain, and plasma samples. Additionally, phase I biotransformation enzyme activities and phase I and II messenger ribonucleic acid (mRNA) expression were investigated in the liver, brain, or both. Both contaminant exposure and reduced food intake had an increasing effect on the concentrations of HOCs and their metabolites. The HOC exposure and reduced food intake also led to increased 7-ethoxyresorufin-O-deethylation (EROD) activity, whereas mRNA expression of the biotransformation enzymes increased only following the reduced food intake. Tissue distribution of HOCs and their metabolites was not affected by either contaminant exposure or reduced food intake. In conclusion, the results indicate that biotransformation capacity and formation of HOC metabolites increase during reduced food intake. This finding supports the hypothesis that reduced food intake increases the susceptibility of Arctic animals to the effects of lipophilic HOCs. Environ. Toxicol. Chem. 2013;32:156-164. # 2012 SETAC

show abstract

The estimation of total serum lipids by a completely enzymatic ‘summation’ method

Cited by 219 publications

References 18 publications

Can polychlorinated biphenyl (PCB) signatures and enantiomer fractions be used for source identification and to age date occupational exposure?

Can polychlorinated biphenyl (PCB) signatures and enantiomer fractions be used for source identification and to age date occupational exposure?

Dioxin-Like TEQ of women from the Seveso, Italy area by ID-HRGC/HRMS and CALUX

Effect of reduced food intake on toxicokinetics of halogenated organic contaminants in herring gull (Larus argentatus) chicks

Contact Info

Product

Resources

About