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Hypercholesterolemia is common in preterm infants administered 10 Intralipid perhaps because of excess phospholipid in plasma causing efflux of cholesterol from tissues. The purpose of this study was to determine if cholesterol synthesis (as measured by plasma lathosterol) is increased in preterm infants (23–32 wk gestation) during infusion of up to 4 g 10 Intralipid/kg body wt/d. Two groups of infants were studied. Intralipid intake was compared to: 1) plasma cholesterol in blood sampled over the first 100 d of life (preliminary study, n= 22) and 2) plasma cholesterol, lathosterol, and apo AI and B in blood taken at birth (cord), d 3–4 of life, and at least three additional times over the next 25 d (lathosterol study, n= 22). Lathosterol was quantitated by gas liquid chromatography and apo AI and B by immunoprecipitation. In the preliminary study, plasma cholesterol levels rose (to 4.06–10.70 mM) with Intralipid administration. Infants who received <2 g Intralipid/kg body wt/d were not hypercholesterolemic. In the lathosterol study, plasma cholesterol increased (1.86–2.24 mM, p= 0.06) and apo AI and B did not change, but lathosterol and the cholesterol:lathosterol ratio decreased (5.24–2.88 μM, p= 0.01, and 284–124 102± mmol lathosterol:mol cholesterol, p= 0.007, respectively) from birth to d 3–4 (n= 11 paired samples). Infants followed longitudinally had increased cholesterol and lathosterol (4− to 7-fold) with increasing Intralipid administration, which decreased after discontinuation of infusion. Apo AI and B decreased upon Intralipid infusion. The results of this study show that 10 Intralipid administration to preterm infants (23–32 wk gestation) results in increased plasma lathosterol. The coincident fall in plasma apo AI and B suggests that the elevated cholesterol synthesis may be extrahepatic.

Hypercholesterolemia is common in preterm infants administered 10% Intralipid perhaps because of excess phospholipid in plasma causing efflux of cholesterol from tissues. The purpose of this study was to determine if cholesterol synthesis (as measured by plasma lathosterol) is increased in preterm infants (23–32 wk gestation) during infusion of up to 4 g 10% Intralipid/kg body wt/d. Two groups of infants were studied. Intralipid intake was compared to: 1) plasma cholesterol in blood sampled over the first 100 d of life (preliminary study, n = 22) and 2) plasma cholesterol, lathosterol, and apo AI and B in blood taken at birth (cord), d 3–4 of life, and at least three additional times over the next 25 d (lathosterol study, n = 22). Lathosterol was quantitated by gas liquid chromatography and apo AI and B by immunoprecipitation. In the preliminary study, plasma cholesterol levels rose (to 4.06–10.70 mM) with Intralipid administration. Infants who received <2 g Intralipid/kg body wt/d were not hypercholesterolemic. In the lathosterol study, plasma cholesterol increased (1.86–2.24 mM, p = 0.06) and apo AI and B did not change, but lathosterol and the cholesterol:lathosterol ratio decreased (5.24–2.88 µM, p = 0.01, and 284–124 102± mmol lathosterol:mol cholesterol, p = 0.007, respectively) from birth to d 3–4 (n = 11 paired samples). Infants followed longitudinally had increased cholesterol and lathosterol (4- to 7-fold) with increasing Intralipid administration, which decreased after discontinuation of infusion. Apo AI and B decreased upon Intralipid infusion. The results of this study show that 10% Intralipid administration to preterm infants (23–32 wk gestation) results in increased plasma lathosterol. The coincident fall in plasma apo AI and B suggests that the elevated cholesterol synthesis may be extrahepatic.

Abstract: Experimental investigations were conducted to examine the behavior of concrete sandwich composites under compressive and tensile loads. The sandwich cores were composed of nonpermeated, expanded aluminum honeycomb and the facings consisted of concrete mortar. Appropriate theories that predict the behavior of such composites were presented and compared with experimental data. All specimens had facing thicknesses of 1 in. (25.4 mm), core thicknesses of 1, 2 and 3 in. (25.4, 50.8 and 76.2 mm); core-cell size of 1/8 and 3/8 in. (3.2 and 9.5 mm); while four different core foil gages were considered for each size. The facings were either plain concrete mortar or reinforced with steel wires.The large-core-cell-size specimen displayed better bond characteristics and produced more consistent experimental data. The ultimate strengths of both compressive and tensile specimens were not affected by the core-cell size, core thickness, or core density. Axial compressive loads were carried by the facing area while tensile loads were by the reinforcements in the facings. The buckling waves were developed due to the wrinkling of the facings. The buckling waves in the two facings were independent of each other and the overall wave pattern was antisymmetrical.

Abstract: An experimental investigation was carried out to examine the flexural behavior of rectangular sandwich composites and to determine appropriate structural applications for such constructions. The sandwich cores were composed of nonpermeated, expanded aluminum honeycomb and the facings consisted of concrete mortar. Appropriate theories that predict the behavior of such composites were presented and compared to experimental data. All specimens had facing thicknesses of 1 in., core thicknesses of 1 in., 2 in. and 3 in.; core-cell size of 1/8 in. and 3/8 in.; while four different core foil gages were considered for each cell size. The lower facing was either plain concrete mortar or reinforced with steel wires. The large cell-size specimen displayed better bond characteristics and produced better and more stable experimental data. Reasonable agreement was found between the observed and computed flexural stresses. The deflections at midspan were in good agreement with the theoretically predicted deflections in all of the specimens, with or without reinforcement. Regardless of cell size, density, core thickness or reinforcement, the observed midspan and quarterspan deflections of the top facing were approximately twice the deflections at the corresponding locations on the lower facing. The ultimate loads increased as the core thickness and the core density increased. The influence of flexural rigidity of the core can be neglected.