Call number: LD2668 .T4 1932 B42

Call number: LD2668 .T4 1939 H81 / Master of Science

LD2668 .T4 1939 P71 / Master of Science

LD2668 .T4 1942 G3 / Master of Science

Call number: LD2668 .T4 1948 N44 / Master of Science

Call number: LD2668 .T4 1928 K51

The effect of increased egg consumption on plasma cholesterol levels and its distribution among lipoproteins and Apolipoprotein A-I/A-II ratios of high density lipoprotein subfractions in individuals who did and did not demonstrate response in plasma cholesterol levels was studied in 20 healthy middle-aged men (30-55 years of age) for three months. Lunch containing 3 eggs was fed all subjects during the first month classification period. Subsequently, subjects were divided into hyper and hyporesponders according to their blood cholesterol level. Thereafter, 6 eggs were fed to hypo (n=12) while hyper (n=8) continued to consume 3 eggs with lunch. The average plasma cholesterol level of the 20 subjects was increased from 185±34 to 195±34 mg/lOOml during the classification period. The mean plasma cholesterol level of the hyperresponders was significantly (p<0.025) increased from 170±42 to 199±40 mg/100ml during classification while that of the hyporesponders fell slightly. The additional 6 eggs consumed by the hyporesponders for 6 weeks did not increase the mean plasma cholesterol level. The apoprotein ratios did not change as a result of the increased cholesterol diet and were not significantly different between the two response groups. The hyper and hyporesponders differed significantly in initial plasma cholesterol parameters that diminished as the subjects were challenged with increased cholesterol consumption. These initial differences included a significantly lower low density lipoprotein cholesterol/high density lipoprotein cholesterol ratio of 2.26±0.6 for hyperresponders compared to 3.31±0.9 for hyporesponders. There were also initial differences in the percentage of whole plasma cholesterol found in the HDL fractions: hyperresponders had a greater percentage of total and free cholesterol in the HDL and HDL-2 fractions and a greater percentage of total cholesterol in the HDL-3 fraction. The present data demonstrate that increased cholesterol consumption will increase plasma cholesterol levels and that there is individual variability of plasma cholesterol response as a result of feeding cholesterol. / Graduation date: 1984

No description available.

Manduca sexta vitellogenin is a phosphoglycolipoprotein (Mᵣ ∼ 500,000) that contains two copies of the apoproteins (apovitellogenin-I, Mᵣ 180,000 and apovitellogenin-II Mᵣ 45,000), 13 percent lipids, 3 percent carbohydrates and 0.6 percent phosphorus. The two apoproteins are immunologically distinct and apovitellogenin-II is not completely accessible to the aqueous environment in the intact molecule. The carbohydrate moiety located on apovitellogenin-I has a high mannose structure (Man₉ GlcNAc₂). Follicle membranes bind ¹²⁵I-labeled vitellogenin with high affinity and specificity (K(D) ≃ 1.3 x 10⁻⁸ M). Total binding sites were estimated at 4 x 10¹⁴ sites/g of follicle membrane protein. The binding was sensitive to pH and calcium. Competition studies showed that binding of vitellogenin was blocked by vitellin and deglycosylated vitellogenin but not by lipophorin, microvitellogenin or apovitellogenin-II. These results suggest that the uptake of vitellogenin involves binding to specific receptors on follicle membranes and the carbohydrate moiety and apovitellogenin-II are not involved in the interaction with the receptors.

No description available.