Bovine Serum Albumin

Interaction thermodynamics between warfarin, a very popular anticoagulant, and Sudlow I binding site of human (HSA) or bovine (BSA) serum albumin have been examined in strictly controlled experimental conditions (HEPES buffer 50 mM, pH 7.4 and 25 °C) by means of isothermal titration calorimetry (ITC), fluorescence spectrometry (FS) and frontal analysis capillary electrophoresis (FA/CE). Each technique is based on measurements of a different property of the biochemical system, and then the results allow a critical discussion about the suitability of each approach to estimate the drug-protein binding parameters. The strongest interaction step is properly evaluated by the three assayed approaches being the derived binding constants strongly consistent: from 4 × 104 to 7 × 104 for HSA and from 0.8 × 105 to 1.2 × 105 for BSA. Binding enthalpy variations also show consistent results: -5.4 and -5.6 Kcal/mol for HSA and -4.3 and -3.7 Kcal/mol for BSA, as measured by ITC and FS, respectively...

A keratinase enzyme was isolated and purified from a feather-degrading culture of Aspergillus oryzae. Fractional precipitation of the crude enzyme with ethanol, acetone and ammonium sulfate yielded 21 fractions. The fraction obtained at 75–85% ammonium sulfate saturation ...

One of the key stimulators of intestinal development in the chick is physical exposure to feed, while feed withholding delays the onset of gut development. A delay of 24–72 h in onset of feeding is quite common in the poultry industry due to variation in hatching time and hatchery treatments. As intestinal development occurs in concert with the development of the gut associated lymphoid tissue (GALT), we investigated the effects of short term feed withholding on development of GALT in broiler hatchlings. GALT activity was determined by antibody production (systemic and locally in the gut), distribution of B and T lymphocytes in the gut, expression of lymphocyte specific genes, and distribution of B and T lymphocytes in the cloacal bursa. Our findings show that while development of GALT in the foregut (duodenum, jejunum, ileum) was only slightly and temporarily impeded by feed withholding, GALT activity in the hindgut and the gut-related cloacal bursa was significantly delayed during the first 2 weeks of life: Systemic and intestinal antibody responses following rectal immunization to antigen were lower, colonization of the hindgut (cecum and colon) by T and B lymphocytes was delayed, as well as the expression of chIL-2 mRNA in hindgut T lymphocytes. We also found that the increase of B and T population size in the cloacal bursa was delayed with time. Full recovery occurred from 2 weeks of age. The 2-week vulnerable period should be seriously considered in circumstances where hatchlings are in transit for extended periods from hatcheries to farms.

To determine the possible association between anemia and clinical and echocardiographic cardiac disease, a cohort of 432 end-stage renal disease patients (261 on hemodialysis and 171 on peritoneal dialysis) who started dialysis therapy between 1982 and 1991 were followed prospectively for an average of 41 months. Baseline demographic, clinical, and echocardiographic assessments were performed, as well as monthly serial clinical and laboratory tests while the patients were on dialysis therapy. The mean (+/-SD) hemoglobin level during dialysis therapy was 8.8 +/- 1.5 g/dL. After adjusting for age, diabetes, and ischemic heart disease, as well as for blood pressure and serum albumin levels measured serially, each 1 g/dL decrease in mean hemoglobin was independently associated with the presence of left ventricular dilatation on repeat echocardiogram (odds ratio, 1.46; P = 0.018) and the development of de novo (relative risk [RR] = 1.28; P = 0.018) and recurrent (RR = 1.20; P = 0.046) cardiac failure. In addition, each 1 g/dL decrease in the mean hemoglobin level was independently associated with mortality while the patients were on dialysis therapy (RR = 1.14; P = 0.024). Anemia had no independent association with the development of ischemic heart disease while the patients were on dialysis therapy. Anemia, an easily reversible feature of end-stage renal disease, is an independent risk factor for clinical and echocardiographic cardiac disease, as well as mortality in end-stage renal disease patients.

The objective of this study was to evaluate the nutritional impact of therapeutic elimination diets and to identify risk factors predisposing infants with food allergy to poor growth. We studied 100 children (mean age 7 months) with atopic dermatitis and challenge-proven cow's milk allergy and evaluated their growth during the symptomatic period before diagnosis and during the therapeutic elimination diet. Clinical control of symptoms was achieved in all patients. The mean length SD score and weight-for-length index of patients decreased compared with those in healthy age-matched children, p < 0.0001 and p = 0.03, respectively. Low serum albumin was present in 6% of the patients, 24% had an abnormal urea concentration, and 8% had a low serum phospholipid docosahexaenoic acid. The delay in growth was more pronounced in a subgroup of patients with early onset than in those with later of symptoms (F = 6.665, p < 0.0001). The duration of breast-feeding correlated positively with the sum of n-3 polyunsaturated fatty acids (r = 0.39, p = 0.001) and with the relative amount of docosahexaenoic acid (r = 0.36, p = 0.002). A delicate balance exists between the benefits and the risks of elimination diets.

The purpose of this study was the classification and identification of drug binding sites on albumins from several species in order to understand species differences of both drug binding properties and drug interaction on protein binding. Binding properties and types of drug-drug interaction on the different albumins were examined using typical site I binding drugs, warfarin (WF) and phenylbutazone (PBZ), and site II binding drugs, ibuprofen (IP) and diazepam (DZ) on human albumin. Equilibrium dialysis was carried out for two drugs and the free concentrations of drugs were then treated using the methods of Kragh-Hansen (Mol. Pharmacol. 34. 160-171, (1988)). Binding affinities of site I drugs to bovine, rabbit and rat albumins were reasonably similar to human albumin. However, interestingly, those to dog albumin were considerably smaller than human albumin. On the other hand, binding parameters of DZ to bovine, rabbit and rat albumins were apparently different from those of human alb...

To characterize the binding site of propranolol hydrochloride, the free concentration of warfarin (site-I-specific probe) bound to BSA was measured upon the addition of propranolol hydrochloride. It was found that the free concentration of warfarin sodium was increased from 100% (as % of initial) to 552.35% when the ratio of propranolol to BSA was increased 1–6. In contrast, under the

The physiological alpha-oxoaldehyde methylglyoxal binds and modifies arginine, lysine, and cysteine residues in proteins. The kinetics and mechanism of these reactions were investigated with N alpha-acetylamino acids and bovine serum albumin at pH 7.4 and 37 degrees C. The reaction of methylglyoxal with N alpha-acetylarginine involved the initial reversible formation of glycosylamine and 4,5-dihydroxy-5-methylimidazolidine derivatives, with further slow irreversible conversion to an imidazolone, N alpha-acetyl-N delta- (5-methyl-4-imidazolon-2-yl)ornithine. The imidazolone was fluorescent with an excitation lambda max value of 320 nm and an emission lambda max value of 398 nm. Methylglyoxal reacted reversibly with N alpha-acetyllysine to form glycosylamine and bisglycosylamine derivatives. Further reaction of these glycosylamines occurred to form brown, fluorescent oligomers that were not characterized. Methylglyoxal reacted rapidly and reversibly with N alpha-acetylcysteine to form...