Polyethylene Glycol Succinate Research Articles

IRON SUPPLEMENTATION BY 3 MONTHS OF AGE IS NECESSARY IN LOW BIRTH WEIGHT INFANTS

Prevention of iron deficiency in low birth weight infants requires iron supplementation before the age when neonatal iron stores are exhausted. In order to determine this age, we measured hemoglobin (Hb), mean corpuscular volume(MCV), serum iron/iron binding capacity (% Sat), serum ferritin (SF), and reticulocyte count (retic) at 0.5, 1, 2, 3, 4 and 5 or 6 mo of age in 117 infants whose birth weights were between 1000 and 2000 g. All received banked breast milk in the hospital and breast milk or cows' milk formula later. A daily vitamin supplement included 5 IU vitamin E as tocopherol polyethylene glycol-1000 succinate. Infants with odd birth dates received 2 mg iron as ferrous sulfate/kg/d starting at 0.5 mo; those with even birth dates received no additional iron unless they developed anemia (Hb<7 g/dl at 2 mo, <9 at 3 mo, <9.5 at 4 mo, and <10.4 at 5 mo). At 2 mo, only the SF was significantly lower in the no-iron group (p<0.02); Hb and retic showed no evidence of vitamin E deficiency. At 3 mo, Hb, MCV, % Sat and SF were all lower (p<0.001, <0.01, <0.001 and <0.02) in the no-iron group. There was no significant difference between infants who were changed to formula and those who were still exclusively breast fed. The results indicate that low birth weight infants who receive no supplemental iron may develop iron deficiency by 3 mo of age. An iron dose of 2 mg/kg/d started at 2 weeks of age is adequate to prevent iron deficiency.

Separation of fluorobromobenzenes by gas-liquid chromatography

Fluorobromobenzenes were separated on squalane, silicone oil. polyethylene glycol (1500), polyethylene glycol succinate, polyoxyethylene sorbitan monostearate, di- n-decyl phthalate and polypropylene glycol. Specific retention volumes, band impurities, and electron polarisabilities were calculated and reported.

Gas—liquid chromatography of disubstituted benzene isomers : II. Separation and study of the halonitrobenzenes, anisoles and toluenes

Quantitative separation of halonitrobenzenes, anisoles and toluenes was studied on polyethyleneglycol, polyethyleneglycol succinate, polyoxyethylenesorbitan monostearate, silicone oil and squalane as liquid phases. The interactions and forces that affected the separation of the isomers and their elution sequences were discussed. It was found that polyethyleneglycol succinate and polyoxyethylenesorbitan monostearate could selectively separate all the isomers studied.

Gas—liquid chromatography of disubstituted benzene isomers : I. Separation and study of the dichlorobenzenes

Dichlorobenzene isomers were separated on squalane, silicone oil, polyethyleneglycol, polyoxyethylenesorbitan monostearate and polyethyleneglycol succinate. Types of interactions and forces which affected the specific retention volumes and elution orders were discussed. Thermodynamic quantities were calculated and studied on squalane and polyethyleneglycol. Polyesters were selective for the separation of these isomers.

Peroxidative Hemolysis of Red Blood Cells from Patients with Abetalipoproteinemia (Acanthocytosis)*

The effect of peroxidative stress on tissue was studied by exposure of red blood cells (RBC) from patients with abetalipoproteinemia to minute amounts of H(2)O(2)in vitro. Red blood cells from untreated patients showed a marked sensitivity to H(2)O(2), as evidenced by hemolysis and lipid peroxidation (peroxidative hemolysis). The appearance of lipid peroxidation products in sensitive cells after exposure to H(2)O(2) was indicated by 1) increases in the 2-thiobarbituric acid (TBA) reaction of trichloroacetic acid extracts, 2) increases in ultraviolet light absorbency of lipid extracts, and 3) decreases in polyunsaturated fatty acids. These changes were accompanied by a decrease in phosphatidyl ethanolamine and phosphatidyl serine in the RBC lipid extract. Similar lipid changes on exposure to H(2)O(2) were observed in the RBC from vitamin E-deficient rats. Treatment of the patients with d-alpha-tocopherol polyethylene glycol succinate by mouth, or addition of dl-alpha-tocopherol to the incubation medium protected the RBC from peroxidative hemolysis. Tocopherol appears to provide a primary biologic defense against peroxidative hemolysis. The presence of nitrite or carbon monoxide, which produced methemoglobin and carboxyhemoglobin, respectively, inhibited peroxidative changes, suggesting a catalytic role for oxy- or deoxyhemoglobin. Substances that prevented lipid peroxidation also prevented hemolysis; in addition, lipid peroxidation appeared to precede hemolysis. These observations suggested that hemolysis was a consequence of lipid peroxidation.

Gas-liquid chromatography of certain macrocyclic compounds

1. A method of analyzing alicyclic ketones C5 — C17 with b.p. up to 370°,α-cyclothienones C14 — C17 with b.p. up to 410°, as well as alcohols of the thiophene series, was developed by gas-liquid chromatography. Polyethylene glycol succinate is a suitable phase for the separation. 2. A linear relationship between the logarithm of the relative retainable volume and the boiling point (and the number of carbon atoms), permitting the identification of unknown components, was found. 3. The heats of solution were determined for cyclic ketones and cyclothienones in polyethylene glycol succinate.

Gas-liquid chromatography of methylcyclohexanols and their ethers

The Chromatographic separation of the stereoisomers of 2-, 3-, and 4-methyl-cyclohexanols and their butyl and phenyl ethers was carried out on stationary phases-polyethylene glycol adipate applied on diatomite brick, treated with alkali, and polyethylene glycol succinate on chromosorb.

Effects of Digitonin and Tocopherol on Bovine Heart Muscle Reduced Diphosphopyridine Nucleotide- and Succinate-Cytochrome c Reductase and Cytochrome c Oxidase

The effects of digitonin and tocopherol on bovine heart reduced diphosphopyridine nucleotide- and succinate-cytochrome c reductases and cytochrome c oxidase have been studied with the following results. 1. Low concentrations of digitonin stimulate succinate- and DPNH-cytochrome c reductase and cytochrome c oxidase. Higher concentrations of digitonin completely inhibit cytochrome c reductases, while continuing to stimulate cytochrome c oxidases. 2. Inhibition of the reductases is reversed by either dilution or addition of tocopherol. Stimulation of the reductases and oxidase is prevented by tocopherols but is not reversed by either tocopherols or dilution. 3. Of other compounds tested for ability to prevent these digitonin effects, α-tocopherol polyethylene glycol succinate 1000 and coenzyme Q4 chromanol were effective with a soluble preparation of DPNH-cytochrome c reductase. In addition to these, α-tocopheryl succinate and α-tocopheryl phosphate were effective with a particulate preparation of succinate-cytochrome c reductase. α-Tocopheryl succinate, α-tocopheryl phosphate, α-tocopheryl hydroquinone, and vitamin D2 prevented the stimulation of cytochrome c oxidase. 4. Digitonin stimulation of succinate-cytochrome c reductase is associated with increases in both Vmax and Km (succinate); digitonin inhibition is associated with decreases in both Vmax and Km (succinate). 5. Reduced with respect to oxidized difference spectra of normal and inhibited preparations indicated succinate reduction of cytochromes a + a3, b, and c1, and of flavin in the normal enzyme, but almost no reduction of flavin and cytochromes of a digitonin-inhibited enzyme. 6. Digitonin caused almost complete inhibition of enzymatic reduction of ferricyanide by succinate, but only partial inhibition of reduction of indophenol and phenazine methosulfate. It is concluded from this and from the spectral studies that inhibition is before cytochrome b and after, or at, the flavin. 7. Digitonin stimulates both the reduction or oxidation of cytochrome c but not the reduction of ferricyanide. It is concluded that stimulation is due to irreversible changes in the enzyme that permit more rapid reaction of soluble cytochrome c with the particulate enzyme. 8. Tocopherol apparently forms an insoluble complex with digitonin and decreases the concentration of digitonin in solution. This is possibly the mechanism by which tocopherol counteracts the effects of digitonin on enzymes. Other compounds known to combine with digitonin do not decrease the concentration of digitonin under the conditions of the enzyme assays.

Quantitative analysis of carbohydrates using gas-liquid chromatography

Sugars can be analyzed quantitatively as their trimethylsilyl derivatives using gas-liquid chromatography. Standardization of polyethylene glycol succinate columns with α-methylgalactopyranoside as the standard gave a quantitative correlation between GLC relative peak areas and relative molar compositions of sugar standard solutions for: the pentose, ribose; the deoxyhexose, fucose; and the hexoses, glucose, galactose, and mannose. Quantitative data were also obtained for N-acetylamino sugars. Mixtures of sugars were analyzed by using the standardization graphs, and the amounts determined were accurate within 10%. This use of GLC will make it easier for the biochemist to attack problems in carbohydrate chemistry by enabling quantitative work to be done readily on mixtures heretofore difficult to analyze.

STUDIES OF TOCOPHEROL REQUIREMENTS IN HEALTH AND DISEASE

Premature infants were fed an artificial formula essentially free of tocopherol over the first 6 months of life. These infants were compared to two other groups of prematures one fed a formula of "average" tocopherol content, and the third group a tocopherol-fortified product. Although the use of the "tocopherol-free" product resulted in extremely low tocopherol concentration in serum, no significant differences were observed in the three groups of infants with respect to weight increment, hemoglobin concentration, erythrocyte counts, hematocrit value, or in erythrocyte glutathione and glucose-6-phosphate dehydrogenase activity. The requirements of the normal premature infant are met by a formula containing 3.0 mg of alpha tocopherol per liter of formula, in terms of achieving normal concentrations in serum during a 1-to-2-month period. Absorption studies in healthy full-term infants in the first week of life failed to reveal any significant differences in the degree of absorption of tocopherol as d-alpha tocopherol acetate, d-1 alpha tocopherol acetate and d alpha tocopheryl polyethylene glycol succinate, when administered in test doses providing 2.0 and 10.0 mg of free tocopherol. Observations on the effects of tocopherol supplementation on concentrations in serum of healthy full-term infants fed partly skim milk formula suggest that a daily supplement providing 0.5 mg of free tocopherol is adequate to produce a rapid rise to normal serum levels. However, except in terms of tocopherol concentrations, this study does not answer the question of true biological need for a tocopherol supplement in artificially fed infants. Because of the variable but marked decrease in tocopherol absorption in children with fibrocystic disease, very large supplements are necessary to maintain normal levels in serum. The observations reported here suggest that a minimum supplement of 100 mg tocopherol per day (free to-copherol as d-alpha tocopheryl polyethylene glycol succinate) is likely to be necessary in such patients, in order to restore serum concentrations to normal.

The heart in pseudohypertrophic muscular dystrophy

Summary A study of 2 cases in a family in which 4 male siblings have died with evidence of progressive muscular dystrophy of skeletal and cardiac muscle and in which 2 living male siblings who have this disease also have cardiac involvement is reported. Pathologic study in one case showed evidence of extensive cardiac muscular dystrophy and marked endocardial fibroelastosis. The literature of cardiac involvement in the muscular dystrophic process is reviewed, and the salient clinical and electrocardiographic findings in this condition are noted. Biochemical studies, including blood glutamic oxalicacetic transaminase and aldolase estimations, showed no difference in this group of cases as compared to those cases with skeletal muscle involvement alone. Intravenous tocopherol polyethylene glycol succinate given to one patient had no effect clinically, biochemically, or cardiologically. The high incidence of cardiac involvement in P.M.D. is stressed, and it is felt that more attention should be given to the management of the cardiac status in the treatment of these patients.

In vitro effect of tocopherol metabolites on respiratory decline in dietary necrotic liver degeneration

The latent phase of necrotic liver degeneration in the rat, produced by dietary deficiency of vitamin E and Factor 3, is characterized by respiratory decline, i.e., a failure of respiration of liver slices in the Warburg. Tocopherol readily reverses this defect when injected intravenously but not when added to the Warburg medium. The in vitro effect of various tocopherol derivatives on respiratory decline was investigated. DL-α-tocopherol, d- α-tocopheryl polyethylene glycol-1000 succinate, DL-α-tocopherylhydroquinone, DL-α-tocopherylquinone, and DL-“α-tocopheroxide” (acetal of α-tocopherylquinone) did not influence the breakdown of respiration. Two tocopherol metabolites, isolated from the urines of rabbits and humans, 2-(3-hydroxy-3-methyl-5-carboxy)-pentyl-3,5,6-trimethylbenzoquinone and its γ-lactone, were found to prevent respiratory decline when added to the Warburg medium. A dose response curve was obtained. The 50% effective dose was at approx. 6.25 μg. The diacetate of the hydroquinone of the lactone was active at higher dose levels. The significance of the findings is discussed. In addition to the effect on respiratory decline, the γ-lactone at levels of 100 μg per flask produced a stimulation of the initial O 2 consumption. The stimulatory effect was less pronounced, but present, with liver slices from normal controls.