Lipid normalized, definition

Edmondson et al (1971), who studied the enrichment of whole milk with iron, found that ferrous compounds normally caused a definite oxidized flavor when added before pasteurization. Aeration before addition of the iron reduced the off-flavor. The authors recommended the addition of ferric ammonium citrate followed by pasteurization at 81 °C. Kurtz et al. (1973) reported that iron salts can be added in amounts equivalent to 20 mg iron per liter of skim milk with no adverse flavor effects when iron-fortified dry milk is reconstituted to skim milk or used in the preparation of 2% milk. Hegenauer et al. (1979A) reported that emulsification of milk fat prior to fortification greatly reduced lipid peroxidation by all metal complexes. These researchers (Hegenauer et al. 1979B) concluded that chelated iron and copper should be added after homogenization but before pasteurization by a high-temperature-short-time process. 

It is apparent that at this stage of development definitive conclusions are premature, and that this aspect of amino acid and lipide metabolism will be pursued vigorously in the near future. It is of considerable interest to us that biotin and pantothenic acid deficiencies affect amino acid transport in L. arabinosus, since both vitamins are known to play a prominent role in lipide biosynthesis. We are currently reexamining the turnover of lipide fractions in nutritionally normal and vitamin-deficient cell types to determine whether there is some relation between this aspect of metabolism and amino acid transport. In any case, the nature of the catalytic steps involved in amino acid transport is still unknown to us. They probably occur in the peripheral cell membrane, but even this elementary and widely accepted belief will require additional study before it can be accepted beyond doubt as an established fact. 

Subsequently, serum lipid and lipoprotein profiles were obtained 70 mg/dL total cholesterol (normal is 130-200 mg/dL), 1 mg/dL HDL cholesterol (optimal is > 60 mg/dL), 180 mg/dL triglycerides (normal is 100-150 mg/dL), and less than 5 mg/dL apolipoprotein A-I (apoA-I normal is 140 mg/dL). Cholesterol efflux from patient skin fibroblasts to apoA-I, the main protein component of HDL, was reduced to 30% of normal. These results indicated Tangier disease, the definitive diagnosis of which was made when the sequencing of the ATP-binding cassette transporter A1 (ABCA /) gene revealed a nonsense mutation within exon 12. 

Definitive information about the clinical effectiveness of DHA is important both for the patients and their families and for the scientific community. Provision of an unproven or ineffective therapy may provide a false sense of security and retard the introduction of new approaches and thus be counter to the patients best interests. Furthermore, there still are unresolved disputes about the optimal modes of DHA therapy. Which DHA preparation is most effective Should arachidonic acid supplementation be provided along with DHA Although at this time the titration of the DHA dosage is based on total levels of this substance in plasma and red blood cells, it is possible that follow-up of the levels of this fatty acid in specific lipid moieties might be more informative. Would it be effective and safe to increase the plasma DHA levels to higher than normal Carefully designed clinical trials are required to answer these questions. 

The term bioaccumulation factor (BAF) is a coefficient used to quantify the net body burden of chemicals (given uptake, distribution, metabolism, and excretion rates) and is expressed as the ratio of the concentration of a compound in the organism (or normalized to the lipid weight of the organism) to the concentration in its food or, for benthic or soil invertebrates, in the sediment or soil [9] (also see Chapter 6). Although by definition, BAF is measured at steady state, due to the complex nature of multiplepathway exposure, steady-state measures of BAF are often difficult to obtain. 

Fig. 16. Bioaccumulation factor (normalized to organism lipid and sediment organic carbon) as a function number of aromatic rings in PAHs. Mean and standard error of the mean BAFi c for PAHs consists of 2-6 aromatic rings. Each mean represents several PAHs and sediments (sites = 7 for amphipod = 5 for polychaete). [See Table 1 for PAHs and ring categories.] Polychaete (Armandia brevis) and amphipod (Rhepoxynius abronius) individuals were exposed to Raritan-Hudson estuary (New York) sediments for 10 d. See Appendix for BAFioc definition. (Data from Meador et al. 1995.)...

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