Complementary effects of bifidogenic growth stimulators and ammonium sulfate in natural rubber serum powder on Bifidobacterium bifidum.
Natural rubber serum powder, rich in crude protein and carbohydrates, had a strong growth-stimulating activity for Bifidobacterium bifidum JCM 1254, which was unable to grow in a fully synthetic medium, B12 assay medium. Natural rubber serum powder was fractionated by ultrafiltration (molecular weight cutoff 1000). The active ultrafiltrate was further concentrated and desalted with an adsorptive microconcentrator, which adsorbs virtually all amino acids and peptides. Through this purification step, it was found that the adsorbed fraction obtained did not stimulate growth independently but acted complementarily with a small amount of ammonium sulfate. The adsorbed fraction was subsequently analyzed on reversed-phase high pressure liquid chromatography, and the activities of the eluates were measured on B12 assay medium with ammonium sulfate. Consequently, it was proved that several peptidic ingredients in the adsorbed fraction increased the growth of B. bifidum. (+info)
Systemic availability of budesonide after nasal administration of three different formulations: pressurized aerosol, aqueous pump spray, and powder.
AIMS: The present study was undertaken to determine the absolute systemic availability of budesonide from three different devices for nasal administration: pressurized aerosol, aqueous pump spray, and powder. METHODS: Sixteen healthy, non-smoking, volunteers participated in this open, randomized, and crossover study. All subjects received budesonide as an intravenous dose of 400 microg, and as three, single-dose, intranasal administrations: pressurized aerosol 800 microg, aqueous pump spray 400 microg, and powder 800 microg. Blood was sampled for 10 h after each administration and budesonide was assayed in plasma by liquid chromatography plus mass spectrometry. RESULTS: The mean [95% CI] systemic availability of budesonide with reference to the metered dose was: 13 [10; 15]%, 29 [23; 37]%, and 20 [16; 23]%, and the maximum plasma concentration (Cmax) was attained at (tmax) 2.0, 0.7, and 0.4 h after administration for the pressurized aerosol, aqueous pump spray, and powder, respectively. CONCLUSIONS: The uptake of budesonide was more rapid and more complete, and the systemic availability of the drug was significantly higher from the aqueous pump spray and powder than from the pressurized aerosol. (+info)
Evolution of the internal dynamics of two globular proteins from dry powder to solution.
Myoglobin and lysozyme picosecond internal dynamics in solution is compared to that in hydrated powders by quasielastic incoherent neutron scattering. This technique is sensitive to the motions of the nonexchangeable hydrogen atoms in a sample. Because these are homogeneously distributed throughout the protein structure, the average dynamics of the protein is described. We first propose an original data treatment to deal with the protein global motions in the case of solution samples. The validity of this treatment is checked by comparison with classical measurements of the diffusion constants. The evolution with the scattering vector of the width and relative contribution of the quasielastic component was then used to derive information on the amount of local diffusive motions and their characteristic average relaxation time. From dry powder to coverage by one water layer, the surface side chains progressively acquire the possibility to diffuse locally. On subsequent hydration, the main effect of water is to improve the rate of these diffusive motions. Motions with higher average amplitude occur in solution, about three times more than for a hydrated powder at complete coverage, with a shorter average relaxation time, approximately 4.5 ps compared to 9.4 ps for one water monolayer. (+info)
Liquid concentrates are lower in bioavailable tryptophan than powdered infant formulas, and tryptophan supplementation of formulas increases brain tryptophan and serotonin in rats.
The bioavailability of tryptophan in powdered and/or liquid concentrate forms of milk-based infant formulas was determined by studying rat growth response by using a slope ratio method (food conversion efficiency: weight gain/food consumed vs. tryptophan consumed). A gelatin basal diet formulated to be adequate in all nutrients, except tryptophan (0.03%), for rat growth was supplemented with graded levels of crystalline L-tryptophan (0.02, 0. 04, 0.06, 0.08, 0.10, 0.12 and 0.14%, standard diets) or infant formulas providing 0.04 and 0.08% supplemental tryptophan (test diets). These diets were fed to weanling rats for 2 wk. Tryptophan bioavailabilities of various formulas varied from 83 to 95%, with some of the liquid concentrates having the lowest values. The levels of bioavailable tryptophan in the liquid concentrate forms (9.7-12.6 mg/g protein) and the powdered forms (11.1-13.1 mg/g protein) were considerably lower than those of human milk (17-19 mg/g protein). Supplementation of the liquid concentrates with graded levels of L-tryptophan (0.1, 0.5 and 1.0%) had no effect on protein quality indices, based on rat growth, but resulted in a dose-related increase in the concentrations of tryptophan in the plasma and brain and of serotonin and 5-hydroxyindole-3-acetic acid in the brains of rats. This study supports further research to investigate the influence of tryptophan supplementation of infant formulas, to more closely simulate tryptophan composition of human milk, on tryptophan metabolites and their potential related effects on sleep latency and neurobehavioral developments in infants. (+info)
Dose-proportional pharmacokinetics of budesonide inhaled via Turbuhaler.
AIMS: The present pharmacokinetic study was undertaken to determine the dose proportionality of three different doses of budesonide-400 microg, 800 microg or 1600 microg administered twice daily by a dry-powder inhaler (Turbuhaler ) in adult patients with mild asthma. METHODS: A total of 38 patients received budesonide by inhalation, 13 received 400 microg twice daily, 12 received 800 microg twice daily and 13 received 1600 microg twice daily. Mean FEV1 at inclusion was 3.4, 4.0 and 3.9 l min-1 in the three groups, respectively. Blood samples were taken after a single dose, and after 3 weeks of daily treatment, for pharmacokinetic evaluation. Plasma concentrations of budesonide were determined by liquid chromatography plus mass spectrometry. RESULTS: Eleven evaluable patients remained in each dose group. Mean time to peak budesonide plasma concentration (tmax ) was short (0.28-0.40 h) and did not differ between treatment groups. Budesonide concentrations declined rapidly thereafter, indicating efficient pulmonary absorption and rapid elimination with a half-life of approximately 3 h. Cmax was 1. 4(2.0) nmol l-1 (single (repeated) doses), 2.6(3.6) nmol l-1 and 5. 4(6.4) nmol l-1 after 400, 800 and 1600 microg twice daily, respectively. The corresponding results for the area under the plasma concentration vs time curve (AUC) were 271(325), 490(628) and 915(1096) nmol l-1 min. Ninety percent confidence intervals for pairwise dose-normalized Cmax and AUC comparisons between groups were large but contained unity in all cases, thus indicating dose-proportional pharmacokinetics. Regression on analysis supported these findings. Mean AUC after repeated doses (AUC(0,12 h,RD)) was on average 23% higher than the mean AUC after single doses (AUC(0, infinity,SD)(P=0.04) with no significant differences between doses, indicating slight accumulation following bid dosing. CONCLUSIONS: In this relatively small study, budesonide inhaled via Turbuhaler appeared to have dose-proportional pharmacokinetics, both within and above the clinically recommended dose range for asthmatic patients. (+info)
Sitostanol administered in lecithin micelles potently reduces cholesterol absorption in humans.
BACKGROUND: Phytosterol feeding in human clinical trials has had generally small and inconsistent effects on serum cholesterol concentrations, raising doubts about the importance of phytosterols in natural diets and supplements. OBJECTIVE: The hypothesis tested was that the low intestinal bioavailability of purified phytosterols can be increased by formulation with lecithin. DESIGN: The ability of sitostanol to reduce cholesterol absorption was measured directly by including hexadeuterated cholesterol tracer in a standard test breakfast and measuring plasma tracer concentration 4 and 5 d later by gas chromatography-negative ion mass spectrometry. The tracer amount after a test meal containing sitostanol was compared with that after an identical meal containing placebo. Each subject served as his or her own control and the order of testing was random. Sitostanol was formulated either as a powder or as a sonicated micellar solution with lecithin. A total of 38 single-meal tests were performed in 6 healthy subjects. RESULTS: Sitostanol powder (1 g) reduced cholesterol absorption by only 11.3 +/- 7.4% (P = 0.2), confirming in vitro data showing poor solubility of sitostanol powder in artificial bile. In contrast, sitostanol in lecithin micelles reduced cholesterol absorption by 36.7 +/- 4.2% (P = 0.003) at a dose of 700 mg and by 34.4 +/- 5.8% (P = 0.01) at a dose of 300 mg. CONCLUSIONS: Sitostanol reduced cholesterol absorption at doses lower than reported previously, but only if presented in lecithin micelles. Properly formulated sitostanol as well as naturally occurring complexes of phytosterol and phospholipid might be therapeutically useful for cholesterol lowering. (+info)
Small intestine contrast ultrasonography.
The entire small bowel can be visualized on ultrasonography after ingestion of nonabsorbable, isosmotic polyethylene glycol electrolyte balanced oral solution, termed small intestine contrast ultrasonography. The aims of this study were to assess whether the ingestion of different volumes of sonographic contrast solution may differently affect (1) small bowel distention and thus its sonographic appearance and (2) the time to visualize the entire small intestine. An additional aim was to identify the minimal amount of contrast solution necessary to visualize the entire small bowel. An ultrasonographic examination of the abdomen was performed twice in six healthy subjects after the ingestion of the isosmotic polyethylene glycol solution. During the first investigation each subject was asked to drink increasing amounts of sonographic contrast solution until the jejunum was visualized at ultrasonography. During the second investigation each subject was asked to drink increasing amounts of sonographic contrast solution, not to exceed a total volume of 260 ml. At the first examination the entire small bowel was visualized 39.3 +/- 17 min after ingestion of 647 +/- 105 ml of contrast solution. At the second examination the entire small bowel was visualized 43.5 +/- 13.5 min (not significant with respect to the first study) after the ingestion of 239 +/- 32 ml of contrast solution (P < 0.01 versus the first study). The mean luminal diameter and wall thickness at three intestinal levels did not differ in the two studies and were not statistically related to the amount of ingested sonographic contrast solution. Loose stools were the only side effect and were reported after the ingestion of more than 600 ml. Ultrasonography offers reproducible information on the morphology of the contrast agent-filled small bowel after ingestion of a wide range of volumes (175 to 820 ml) of isosmotic polyethylene glycol electrolyte balanced solution. On average, the entire small intestine could be visualized on ultrasonography by about 45 min after the ingestion of 600 ml or less of contrast solution without any side effects. (+info)
Garlic powder, effect on plasma lipids, postprandial lipemia, low-density lipoprotein particle size, high-density lipoprotein subclass distribution and lipoprotein(a).
OBJECTIVES: To test the hypothesis that a garlic supplement alters plasma lipoproteins, postprandial lipemia, low-density lipoprotein (LDL) size and high-density lipoprotein (HDL) subclass distribution differently in 50 moderately hypercholesterolemic subjects classified as LDL subclass pattern A or B. BACKGROUND: Garlic has been variably reported to reduce or not affect plasma cholesterol values. Low-density lipoprotein pattern B is a common inherited disorder of lipoprotein metabolism that has been shown to have a significantly greater response to several lipid lowering treatments including low fat diet when compared with LDL pattern A individuals. METHODS: A double blind, randomized, placebo controlled trial in an outpatient lipid research clinic was performed and included fifty moderately hypercholesterolemic subjects (mean LDL cholesterol = 166 +/- 22 mg/dl) classified as LDL subclass pattern A (predominantly large LDL, n = 22) or B (predominantly small LDL, n = 28). Following a two-month stabilization period, subjects were randomly assigned to a placebo or 300 mg three times a day of a standardized garlic tablet for three months. RESULTS: For all subjects, LDL pattern A and B subjects combined, garlic treatment for three months resulted in no significant change in total cholesterol, LDL cholesterol, HDL cholesterol, HDL subclass distribution, postprandial triglycerides, apolipoprotein B, lipoprotein (a) (Lp[a]), LDL peak particle diameter or LDL subclass distribution. There was no significant difference in response for the same parameters among subjects classified as LDL pattern A or B with the exception of significantly greater (p = 0.01) reduction in mean peak particle diameter in pattern A subjects treated with either garlic or placebo. There was no significant change in LDL subclass distribution. CONCLUSIONS: This investigation confirms that garlic therapy has no effect on major plasma lipoproteins and further, that it has no impact on HDL subclasses, Lp(a), apolipoprotein B, postprandial triglycerides or LDL subclass distribution. Garlic may have a greater effect on LDL particle diameter in LDL pattern A compared with pattern B subjects. This difference was not reflected in other plasma lipid measurements. (+info)