scholarly journals Influence of total lipid concentration, bile salt:lecithin ratio, and cholesterol content on inter-mixed micellar/vesicular (non-lecithin-associated) bile salt concentrations in model bile.

1991 ◽  
Vol 32 (9) ◽  
pp. 1501-1512 ◽  
Author(s):  
JM Donovan ◽  
N Timofeyeva ◽  
MC Carey
Keyword(s):  
Bile Salt ◽  
Total Lipid ◽  
Cholesterol Content ◽  
Lipid Concentration ◽  
Total Lipid Concentration ◽  
Model Bile

Interconversions of lipid aggregates in rat and model bile

1991 ◽  
Vol 260 (1) ◽  
pp. G70-G79 ◽  
Author(s):  
T. E. Little ◽  
S. P. Lee ◽  
H. Madani ◽  
E. W. Kaler ◽  
K. Chinn
Keyword(s):  
Bile Salt ◽  
Total Lipid ◽  
Mixed Micelles ◽  
Relative Proportion ◽  
Gel Permeation Chromatography ◽  
Cholesterol Content ◽  
Biliary Fistula ◽  
Micellar Aggregates ◽  
Lipid Aggregates ◽  
Model Bile

The dynamic interchange of cholesterol and the phase transition between nonmicellar and micellar aggregates in rat and model bile were characterized with gel-permeation chromatography, quasi-elastic light scattering, turbidity measurements, and by radiolabeling lipid aggregates in bile. Cholesterol partitioned into either the micellar or nonmicellar phases independent of the lipid aggregate structure. In model bile, increasing bile salt concentrations led to a decrease in the relative proportion of nonmicellar aggregates beginning at 5 mM taurocholate (TC), while the relative cholesterol content of the nonmicellar fraction increased from 1.0 to 2.7 +/- 2.0 (means +/- SD). In rats, creation of a biliary fistula resulted in a decrease of bile salts from 41 to 4 mM. Mixed micelles increased from 25 to 120 A in radius, while nonmicellar aggregates increased from 180 to 800 A in radius. Addition of TC to model bile (cholesterol:lecithin = 1:1) vesicles with total lipid concentrations less than 7 mM yielded a progressive shift of vesicles (450 A) to mixed micelles (30 A). For mixtures with higher total lipid concentrations, addition of TC promoted substantial vesicle aggregation and resulted in formation of a third phase containing lipid aggregates larger in size than the initial vesicles. These results suggest that rapid exchange of cholesterol occurs in bile and that significant remodeling of vesicles can occur. These alterations in vesicles include both enrichment in cholesterol content and formation of larger aggregates during increases in bile salt concentration.

Effects of photoperiod on gluconeogenic activity and total lipid concentration in organs of crabs,Neohelice granulata, challenged by salinity changes

2009 ◽  
Vol 128 (3) ◽  
pp. 261-268 ◽  
Author(s):  
Ana Lúcia Fernandes Chittó ◽  
Vanessa Schein ◽  
Rodrigo Etges ◽  
Luiz Carlos Kucharski ◽  
Roselis Silveira Martins Da Silva
Keyword(s):  
Total Lipid ◽  
Lipid Concentration ◽  
Neohelice Granulata ◽  
Salinity Changes ◽  
Total Lipid Concentration

scholarly journals STUDY ON CAUSE–EFFECT RELATIONS AND OPTIMIZATION OF EXEMESTANE-LOADED NANOSTRUCTURED LIPID CARRIERS

2017 ◽  
Vol 9 (5) ◽  
pp. 68 ◽  
Author(s):  
Le Quoc Thang ◽  
Nguyen Duc Hanh ◽  
Do Quang Duong
Keyword(s):  
Optimal Design ◽  
Total Lipid ◽  
Surfactant Concentration ◽  
Drug Loading ◽  
Nanostructured Lipid Carriers ◽  
Cancer Drug ◽  
Lipid Concentration ◽  
Independent Variables ◽  
Total Lipid Concentration ◽  
Lipid Ratio

Objective: Exemestane is an anti-breast cancer drug, possesses low water solubility and low permeability. This work aimed at the cause-effect relations and optimization of exemestane-loaded nanostructured lipid carriers (EXE-NLCs) for oral delivery.Methods: Excipient screening was based on exemestane solubilities and the emulsification efficiency of surfactants. A D-optimal design based on three independent variables was applied to evaluate the cause-effect relations and optimise EXE-NLCs formulation. The particle size (PS), polydispersity index (PDI), entrapment efficiency (EE) and drug loading (DL) were investigated with respect to three independent variables including liquid lipid to total lipid ratio (X1), surfactant concentration (X2), total lipid concentration (X3).Results: EXE-NLCs were prepared by a hot sonication method employing Labrafac CC and Compritol 888ATO as liquid and solid lipids, respectively, and Cremophor RH40 as a surfactant and Lutrol E-400 as a co-surfactant. All investigated factors: liquid lipid to total lipid ratio, surfactant concentration and total lipid concentration showed significant influences on physicochemical characteristics of EXE-NLCs. The optimal EXE-NLC formulation was composed of liquid lipid to total lipid ratio (X1) of 24 % (w/w), surfactant concentration (X2) of 4 % (w/v) and total lipid concentration (X3) of 4 % (w/v). The PS, PDI, EE and DL of the optimized EXE-NLCs were found to be 41.787 nm; 0.11; 97.605 % and 1.935 %, respectively. The optimized formulation was experimentally examined which demonstrated a good agreement between experimental and predicted values.Conclusion: The cause-effect relations and optimization of EXE-NLCs were investigated and reported for the first time. EXE-NLCs formulation was successfully optimized using D-optimal design and merits further study.

Transfer of n–3 and n–6 polyunsaturated fatty acids from yolk to embryo during development of the king penguin

2001 ◽  
Vol 280 (3) ◽  
pp. R843-R853 ◽  
Author(s):  
Frederic Decrock ◽  
René Groscolas ◽  
Ruth J. McCartney ◽  
Brian K. Speake
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Cholesteryl Ester ◽  
Total Lipid ◽  
King Penguin ◽  
Lipid Transfer ◽  
Lipid Concentration ◽  
Total Lipid Concentration ◽  
High Dietary Intake

This study examines the transfer of lipids from the yolk to the embryo of the king penguin, a seabird with a high dietary intake of n–3 fatty acids. The concentrations of total lipid, triacylglycerol (TAG), and phospholipid (PL) in the yolk decreased by ∼80% between days 33 and 55 of development, indicating intensive lipid transfer, whereas the concentration of cholesteryl ester (CE) increased threefold, possibly due to recycling. Total lipid concentration in plasma and liver of the embryo increased by twofold from day 40 to hatching due to the accumulation of CE. Yolk lipids contained high amounts of C20–22 n–3 fatty acids with 22:6(n–3) forming 4 and 10% of the fatty acid mass in TAG and PL, respectively. Both TAG and PL of plasma and liver contained high proportions of 22:6(n–3) (∼15% in plasma and >20% in liver at day 33); liver PL also contained a high proportion of 20:4(n–6) (14%). Thus both 22:6(n–3) and 20:4(n–6), which are, respectively, abundant and deficient in the yolk, undergo biomagnification during transfer to the embryo.

Lipid and Cholesterol Content of Hepatic Lymph in Experimental Nephrosis

1957 ◽  
Vol 190 (1) ◽  
pp. 180-182 ◽  
Author(s):  
Meyer Friedman ◽  
Ray H. Rosenman ◽  
Sanford O. Byers
Keyword(s):  
Total Lipid ◽  
Cholesterol Content ◽  
Normal Rate ◽  
Lipid Fractions ◽  
Experimental Nephrosis

The lipid and cholesterol content of hepatic lymph, a diffusate of plasma, was determined in nephrotic rats during both the induction and the developed stages of experimental nephrosis. Despite the occurrence of hypercholesteremia and hyperlipemia in such rats, their hepatic lymph was found to contain a normal content of cholesterol and a greatly reduced content of total lipid. These results suggest that in the nephrotic state an intravascular alteration occurs in the various lipid fractions of plasma that interfere with their normal rate of egress from plasma.

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