Reversal of experimental essential fatty acid deficiency by cutaneous administration of safflower oil.
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The intriguing observation that cutaneous application of essential fatty acid (EFA)-rich oil corrects the biochemical abnormalities of EFA deficiency was evaluated in EFA-deficient rats. Approximately 185 mg of safflower oil (140 mg of linoleic acid) were applied daily for 15 days to the kin of EFA-deficient rats. Before and after treatment with the safflower oil, the fatty acid patterns of plasma and erythrocyte phospholipid as well as of plasma triglyceride and cholesterol ester fractions were determined. The linoleic and arachidonic acid content of both plasma and erythrocyte phospholipid increased, while the eicosatrienoic acid content of both fractions decreased. The linoleic acid content of plasma triglyceride increased with safflower oil treatment, but little change occurred in the almost undetectable pretreatment levels of arachidonic and eicosatrienoic acid. In the plasma cholesterol ester fraction, arachidonic acid increased with treatment and eicosatrienoic acid decreased, but the small increase in the linoleic acid content was not statistically significant. Thus, the study confirms the observation that cutaneous application of EFA-rich oils reverses the plasma biochemical manifestation of EFA deficiency. In addition cutaneously applied EFA-rich oils reversed the biochemical manifestations of EFA deficiency in erythrocytes. Whether or not cutaneous application of such oils will prevent EFA deficiency, however, remains to be proven. (+info)
Rheology and stability of water-in-oil-in-water multiple emulsions containing Span 83 and Tween 80.
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Multiple emulsions are often stabilized using a combination of hydrophilic and hydrophobic surfactants. The ratio of these surfactants is important in achieving stable multiple emulsions. The objective of this study was to evaluate the long-term stability of water-in-oil-in-water (W/O/W) multiple emulsions with respect to the concentrations of Span 83 and Tween 80. In addition, the effect of surfactant and electrolyte concentration on emulsion bulk rheological properties was investigated. Light microscopy, creaming volume, and rheological properties were used to assess emulsion stability. It was observed that the optimal surfactant concentrations for W/O/W emulsion long-term stability were 20% wt/vol Span 83 in the oil phase and 0.1% wt/vol Tween 80 in the continuous phase. Higher concentrations of Tween 80 had a destructive effect on W/O/W emulsion stability, which correlated with the observation that interfacial film strength at the oil/water interface decreased as the Tween 80 concentration increased. High Span 83 concentrations increased the storage modulus G' (solidlike) values and hence enhanced multiple emulsion stability. However, when 30% wt/vol Span 83 was incorporated, the viscosity of the primary W/O emulsion increased considerably and the emulsion droplets lost their shape. Salt added to the inner aqueous phase exerted an osmotic pressure that caused diffusion of water into the inner aqueous phase and increased W/O/W emulsion viscosity through an increase in the volume fraction of the primary W/O emulsion. This type of viscosity increase imposed a destabilizing effect because of the likelihood of rupture of the inner and multiple droplets. (+info)
Ostwald solubility coefficients of some industrially important substances.
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Solubility coefficients in blood for benzene, toluene, and xylene were determined as 6.5, 16, and 42 respectively. In lard and olive oil, which were taken to represent human fat, corresponding values were about 450, 1300, and 3900. The coefficient for vinyl chloride in lard and olive oil was 20; the value in blood was too low to be determined by the technique used. Trichloroethylene, used as a marker, was found to have a coefficient in lard of 660, and in olive oil of 710, rather lower values than have been accepted for fat. (+info)
Evaluation of the effects of Neptune Krill Oil on the management of premenstrual syndrome and dysmenorrhea.
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PRIMARY OBJECTIVE: To evaluate the effectiveness of Neptune Krill Oil (NKO) for the management of premenstrual syndrome and dysmenorrhea. SECONDARY OBJECTIVE: To compare the effectiveness of NKO for the management of premenstrual syndrome and dysmenorrhea with that of omega-3 fish oil. METHODS/ DESIGN: Double-blind, randomized clinical trial. SETTING: Outpatient clinic. PARTICIPANTS: Seventy patients of reproductive age diagnosed with premenstrual syndrome according to the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised (DSM-III-R). INTERVENTIONS: Treatment period of three months with either NKO or omega-3 fish oil. OUTCOME MEASURES: Self-Assessment Questionnaire based on the American College of Obstetricians and Gynecologists (ACOG) diagnostic criteria for premenstrual syndrome and dysmenorrhea and number of analgesics used for dysmenorrhea. RESULTS: In 70 patients with complete data, a statistically significant improvement was demonstrated among baseline, interim, and final evaluations in the self assessment questionnaire (P < 0.001) within the NKO group as well as between-group comparison to fish oil, after three cycles or 45 and 90 days of treatment. Data analysis showed a significant reduction of the number of analgesics used for dysmenorrhea within the NKO group (comparing baseline vs. 45- vs. 90-day visit). The between-groups analysis illustrated that women taking NKO consumed significantly fewer analgesics during the 10-day treatment period than women receiving omega-3 fish oil (P < 0.03). CONCLUSION: Neptune Krill Oil can significantly reduce dysmenorrhea and the emotional symptoms of premenstrual syndrome and is shown to be significantly more effective for the complete management of premenstrual symptoms compared to omega-3 fish oil. (+info)
Comparative pharmacokinetics and safety of a novel lyophilized amphotericin B lecithin-based oil-water microemulsion and amphotericin B deoxycholate in animal models.
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Amphotericin B (AmB) has been a most effective systemic antifungal agent, but its use is circumscribed by the dose-limiting toxicity of the conventional micellar dispersion formulation Fungizone (D-AmB). To lower AmB-associated toxicity, AmB may be integrated into oil-in-water lecithin-based microemulsions. The present study compares the pharmacokinetic characteristics of D-AmB with the alternative formulation of AmB in microemulsion (M-AmB), which has proved effective in a murine candidiasis model. Both formulations were given by intravenous bolus: D-AmB 1 mg/kg, and M-AmB 0.5, 1 or 2 mg/kg. The pharmacokinetics of D-AmB and M-AmB have several differences, specifically with regard to the respective Cmax and AUC0- infinity values. Elimination of AmB from serum was biphasic for both M-AmB and D-AmB. Single-dose D-AmB (1 mg/kg) achieved a Cmax of 3.89 +/- 0.48 mg/L and an AUC0- infinity of 32.28 +/- 7.31 mg.h/L, whereas single-dose M-AmB (1 mg/kg) by comparison achieved a lower Cmax (2.92 +/- 0.54 mg/L) and a lower AUC0- infinity (21.89 +/- 5.17 mg.h/L). To evaluate the safety of M-AmB, a multiple-dose toxicity study was performed in groups of 10 mice, each receiving D-AmB 1 mg/kg, or M-AmB 1, 1.5, 2 or 3 mg/kg. The findings suggest that, in comparison with D-AmB, M-AmB produces no histologically demonstrable renal lesions, or changes in clinical chemistry. (+info)
The eyes of most diurnal reptiles and birds contain coloured retinal filters-oil droplets. Although these filters are widespread, their adaptive advantage remains uncertain. To understand why coloured oil droplets appeared and were retained during evolution, I consider both the benefits and the costs of light filtering in the retina. Oil droplets decrease cone quantum catch and reduce the overlap in sensitivity between spectrally adjacent cones. The reduction of spectral overlap increases the volume occupied by object colours in a cone space, whereas the decrease in quantum catch increases noise, and thus reduces the discriminability of similar colours. The trade-off between these two effects determines the total benefit of oil droplets. Calculations show that coloured oil droplets increase the number of object colours that can be discriminated, and thus are beneficial for colour vision. (+info)
Preparation of a water-in-oil-in-water (W/O/W) type microcapsules by a single-droplet-drying method and change in encapsulation efficiency of a hydrophilic substance during storage.
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Microcapsules of a water-in-oil-in-water (W/O/W) emulsion, which contained a hydrophilic substance, 1,3,6,8-pyrenetetrasulfonic acid tetrasodium salt (PTSA), in its inner aqueous phase, was prepared by hot-air-drying or freeze-drying the emulsion using a single-droplet-drying method. Pullulan, maltodextrin, or gum arabic was used as a wall material, and the oily phase was tricaprylin, oleic acid, olive oil, or a mixture of tricaprylin and olive oil. An encapsulation efficiency higher than 0.95 was reached except for the microcapsules prepared using gum arabic and oleic acid. The hot-air-dried microcapsules were generally more stable than the freeze-dried microcapsules at 37 degrees C and various relative humidities. The stability was higher for the microcapsules with tricaprylin as the oily phase than for the microcapsules with oleic acid. The higher stability of the microcapsules with tricaprylin would be ascribed to the lower partition coefficient of PTSA to the oily phase. There was a tendency for the stability to be higher at lower relative humidity for both the hot-air- and freeze-dried microcapsules. The volumetric fraction of olive oil in its mixture with tricaprylin did not significantly affect either the encapsulation efficiency or the stability of the hot-air-dried microcapsules. (+info)
Dietary fatty acids on the control of glucose-6-phosphate dehydrogenase and malic enzyme in the starved-refed rat.
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The role of dietary unsaturated fat in the control of hepatic glucose-6-phosphate dehydrogenase (G6PD) (EC 1.1.1.49) and malic enzyme (ME) (EC 1.1.1.40) was studied in rats subjected to one or two cycles of starvation-refeeding. Rats starved and refed a control (5% corn oil) diet showed a threefold increase in G6PD activity and a twofold increase in ME activity compared to ad libitum-fed rats. After a second cycle of starvation-refeeding G6PD and ME activities showed fourfold and threefold increases, respectively, as compared to ad libitum-fed rats. Feeding rats diets containing 8% linoleic acid (as triglycerides) prevented the increase in G6PD and ME activities upon starvation-refeeding, diets with oleic, palmitic, and stearic acis when fed did not prevent this increase. Feeding rats various combinations of linoleic, linolenic and oleic acids following starvation prevented the additional increase in G6PD and ME activities after a second starvation-refeeding cycle; however, linoleic acid fed alone during the first refeeding prevented the additional increase in ME activity but not in G6PD activity. It is suggested that the dietary control of these enzymes involves one or more specific polyunsaturated fatty acids. (+info)