Lipid levels measurement

The expected outcomes for die patient may include a dierapeutic response to dierapy (lowered blood lipid levels), management of common adverse drug reactions, and an understanding of die dietary measures necessary to reduce lipid and lipoprotein levels. 

The value of the extractable lipid measurement is two-fold. First, it indicates how much lipid has to be removed in the subsequent clean-up process and second, it allows the levels of organic pollutants in the matrix to be expressed on a lipid basis. This normalization reduces the differences among samples purely as a result of the lipid in the sample and the effect of external factors that affect lipid levels. 

Heptachlor epoxide was measured in a strip of skin, fat, and subcutaneous tissue from 68 children who died in the perinatal period and ranged from not detected (nondetectable) to 0.563 ppm (mean 0.173) (Zavon et al. 1969). In 10 other stillborn infants, heptachlor epoxide levels measured in various tissues were as follows brain (nondetectable), lung (0.17 0.07 ppm), adipose (0.32 0.10 ppm), spleen (0.35 0.08 ppm), liver (0.68 0.50 ppm), kidney (0.70 0.28 ppm), adrenal (0.73 0.27 ppm), and heart (0.80 0.30 ppm) (Curley et al. 1969). In another study, the following heptachlor epoxide levels were measured in extracted lipids from mothers and newborn infants maternal adipose tissue (0.28 0.31 ppm), maternal blood (0.28 0.46 ppm), uterine muscle (0.49 0.51 ppm), fetal blood (1.00 0.95 ppm), placenta (0.50 0.40 ppm), and amniotic fluid (0.67 1.16 ppm) (Polishuk et al. 1977a). These data provide evidence of transplacental transfer to the fetus. 

There is limited evidence on the effectiveness of most drugs at the time they are introduced. For example, many drugs are granted marketing authorization based on surrogate endpoints, such as reduction in lipid levels, as the actual effects on health may take a very long time to be measured. The rewards authority would therefore have to make its best estimate as to the risk-benefit profile of the product, and would presumably update the reward level as new information became available. 

Since solubility in blood is altered by many factors, including temperature, lipid level, protein, hemoglobin, and hemocrit values, the solubilities of the gases in the samples should be measured individually. This requires only a second equilibration of the original sample with a new aliquot of helium, and from the ratio of the chromatogram peak heights of the two extractions the solubility of the gas concerned can be calculated. 

Pharmacists have the ability to assess patients for general signs and symptoms of many disease states. In many states, pharmacists are also able to check blood glucose and lipid levels. They are able to measure peak flows in pulmonary patients and can assess minor skin abnormalities and wound care. All these clinical variables may be recorded at baseline and at each subsequent visit to chart changes and/or improvements in the patients condition. 

TCDD levels were measured in the workers at two of the plants. The mean 2,3,7,8-TCDD serum lipid level in 281 production workers in the Newark, New Jersey, and Verona, Missouri, plants was... 

The effects of 2,3,7,8-TCDD exposure in humans exposed in occupational or environmental settings have been described in several studies. Few studies provided precise exposure levels. However, for some cohorts, blood lipid 2,3,7,8-TCDD levels in samples collected shortly after exposure and stored frozen for several years have been analyzed. In other studies, the original blood levels of 2,3,7,8-TCDD were estimated using 2,3,7,8-TCDD levels measured in recent blood samples, the amount of time between exposure and blood sample collection, and a mean serum half-life of 5-12 years. 2,3,7,8-TCDD body burdens calculated from available serum lipid 2,3,7,8-TCDD levels are presented in Table 2-1. 

PeCDD, 1,2,3,4,7,8- and 1,2,3,6,7,8-HxCDD, 1,2,3,4,6,7,8-HpCDD, and OCDD were measured in a mother of twins prior to nursing and after 2 years of nursing (Schecter et al. 1996a). There was a 49.5% decrease in the total amount of CDDs in the lipid fraction of the breast milk. 2,3,7,8-TCDD had the largest percent decline in CDD levels, a decrease of 83.9%. A 52.4% decrease in maternal serum lipid levels of total CDD was also observed the largest percent decline was an 86.8% decline in... 

Individuals exposed through industrial accidents or environmental contamination. Very extensive residential contamination by 2,3,7,8-TCDD occurred in Seveso, Italy, when a 2,4,5-TCP reactor exploded in 1976 (Mocarelli et al. 1991). The contaminated area was divided into three zones based on the concentration of 2,3,7,8-TCDD in the soil. Families in zone A, the most heavily contaminated area based on soil 2,3,7,8-TCDD levels, were evacuated within 20 days of the explosion and measures were taken to minimize exposure of residents in nearby zones. A recent analysis of 19 blood samples from residents of zone A, which were collected and stored shortly after the accident, showed serum lipid levels of 2,3,7,8-TCDD that ranged from 828 to 56,000 ppt. These serum lipid levels are among the highest ever reported for humans (Mocarelli et al. 1991). 

Garbow JR, Kataoka M, Flye MW (2004a) MRI measurement of liver regeneration in mice following partial hepatectomy. Magnetic Resonance in Medicine 52 177-180 Garbow JR, Lin X, Sakata N et al. (2004b) In vivo MRS measurement of liver lipid levels in mice. Journal of Lipid Research 45 1364-1371... 

The discovery of the statin mevalonic acid synthesis inhibitors focused new attention on control of blood lipid levels as a measure to stave off heart disease. A number of compounds have been found that treat elevated lipid levels by other diverse mechanisms. The phosphonic acid derivative ibrolipim (9) is believed to lower those levels by accelerating fatty acid oxidation. The phosphoms-containing starting material 7 can in principle be obtained by the Arbuzov reaction of a protected from of p-bromomethylbenzoic acid (6) with triethyl phosphate. Removal of the protecting group and conversion of the acid to an acyl chloride then affords 7. Condensation of this intermediate with substituted aniline 8 leads to the hypolipidemic agent (9). ... 

An eight week randomized placebo-controlled intervention study reported on the antioxidant status of lead factoiy workers drinking traditional/fermented rooibos (76). The modulation of oxidative status of these workers was shown by a decreased level of lipid peroxidation (measured as malondialdehyde in the plasma) and increased level of blood glutathione (GSH). The authors suggested that rooibos could play a beneficial preventive role in occupationally exposed... 

In any study, it is important that researchers first establish whether or not their data demonstrate a relationship between POP tissue concentration and tissue lipid levels. This is seldom done, as it is typically assumed that such a relationship must exist for lipophilic contaminants. As is compellingly demonstrated by Hebert and Keenley-side47 in their paper To normalize or not to normalize Fat is the question , such assumptions can lead to lipid normalized POP concentrations that are completely at odds with measured wet weight POP values. Further, since factors other than total lipid (such as differences in lipid class, for example) can affect POP levels in organisms, simple ratios (e.g. ng POP/ng lipid) are often inadequate and may actually increase data variability. In many cases, analysis of covariance (ANCOVA) may prove to be a more appropriate method for lipid normalization of POP concentrations47. 

Since hypercholesterolemia (in particular, LDL cholesterol) increases the risk of CHD, it seems reasonable to lower cholesterol levels in patients whose levels put them at risk. Before treatment, other risk factors such as hypertension, cigarette smoking, obesity, and glucose intolerance need to be evaluated and corrected. Disorders that exacerbate hyperlipoproteinemia (e.g., chronic ethanol abuse, hypothyroidism, diabetes mellitus) need to be treated before lipid-lowering measures are taken (discussed earlier. Table 20-7). 

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