Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0393754 (HSA)
 2,996 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have studied the standardization of total serum protein assay with the biuret reaction. Standard solutions were prepared from lyophilized preparations of human serum albumin and bovine serum albumin, with corrections made for volatile material and ash contents. These solutions and a solution of crystalline albumin standard were analyzed with a new stable biuret reagent, to establish absorptivity values (values for the absorbance of a 1 g/liter final reaction mixture). The mean values obtained were 0.302, 0.292, and 0.290 for human serum albumin, bovine serum albumin, and the crystalline albumin, respectively. We believe that the established absorptivity value will improve the accuracy of serum protein determinations. We studied the linearity of the relation between color produced and protein concentration, with use of the solutions described above and a serum pool. The color adheres to Beer's law up to the highest concentration tested: 3 g/liter for HSA and BSA, and 2.8 g/liter for serum in the final reaction mixture. The new biuret reagent has been stable for one year at room temperature. We recommend the use of bovine serum albumin as a primary standard for serum protein assays. It is inexpensive, easily available, and exhibits the best linearity in the biuret reaction.
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PMID:Standards for total serum protein assays--a collaborative study. 116 35

The experimental determination of the operative parameters of two radioimmunoassay (RIA) systems for the determination of triiodothyronine (T3) level directly in serum is described. The two systems differ both for the agents blocking the aspecific T3-serum protein bindings (sulphonic acid, 8-aniline, 1-Naphtalene in borate buffer: bor-ANS-RIA and Merthiolate in phosphate buffer: PO4-Merth-RIA) and for the methods adopted for compensating the aspecific serum interferences (T3,4 free serum for bor-ANS-RIA and Human Serum Albumine HSA 8% for PO4-Merth-RIA. The tracers are T3-I125 (spec. act. 500 Ci/g for bor-ANS-RIA and 1000 Ci/g for PO4-Merth-RIA). The antisera have been raised in rabbit (T3-bovine SA conjugate for bor-ANS-RIA and T3-HSA conjugate for PO4-Merth-RIA). The incubation conditions are 2degreesC X 24 h for bor-ANS-RIA and room temp. X 2 h for PO4-Merth-RIA. For both systems, the Bound-Free (B-F) separations are carried out by charcoal-dextrane adsorption, 4 mg/tube, 10 min contact. Indicatively, the lowest detection limits of the two systems are about 8 pg T3 for ANS and about 6 pg T3 for Merth. Evidence of parallelism and even superimposition is provided for both assays between the dose-response curve and the serum dilution curve. The calibration curves of the employed antisera are reported (final titres: 1/1000 for ANS and 1/2500 for Merth). 4 different incubation conditions for ANS and 2 for Merth are described and the reasons of choice of the mentioned conditions statistically elucidated. Acceptable statistical comparison between "sample-blank" and the "blank" of the diluents of the employed standard preparations are presented and discussed. F-countings vs. B-countings functions are reported (regression line -- equations: F = 0.93 B + 0.07, n = 15, r = 0.993 for ANS and F = 0.95 B -- 0.02, n = 14, r = 0.992 for Merth) demonstrating the possibility of alternative countings. The recovery regression lines (found f vs. expected e) have equations: f = 1.01 e + 0.08, n = 10, r = 0.999 for ANS and f = 1.08 e -- 1.64, n = 9, r = 0.995 for Merth, implying a practically quantitative recovery in both cases. Thyroxine (T4) cross reaction study has been undertaken under a quite new optics re-calculating the regression lines -- equations of the T3 recovery in the presence of added T4; in that case, the following equations are valid: f = 1.05 e + 0,13, n = 10, r = 0.992 for ANS and f = 1.07 e + 2.26, n = 18, r = 0,985 for Merth. Reducing the maximum added T4 to 1 ng/tube, the cross reaction can be considered as negligible. T3 levels for normal subjects are finally reported: 1.50 +/- 0.80, n= 37 for ANS and 1.40 +/- 0.68, n = 40 for Merth (ng T3/ml, means +/- 2SD).
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PMID:[Radioimmunologic determination of plasmatic triiodothyronine. Verification of operative parameters; 1st clinical results]. 122 40

1. Serum protein binding of isradipine and darodipine, and serum concentrations of alpha 1-acid glycoprotein (AAG), albumin (HSA) and non-esterified fatty acids (NEFA) were measured in three groups of patients, I: healthy subjects (n = 20); II: patients with inflammatory disorders (n = 15) and III: patients with hepatic insufficiency (n = 17). 2. AAG was increased significantly in group II patients (P less than 0.001) and decreased in group III patients (P less than 0.001); HSA was decreased significantly in group II and group III patients (P less than 0.001). 3. The free percentage of isradipine was decreased significantly in group II patients (P less than 0.05) and increased in group III patients (P less than 0.05) and multivariate analysis showed that these variations were inversely related to changes in AAG concentration. 4. The free percentage of darodipine was increased significantly in group II and III patients (P less than 0.05) due to a decrease in HSA concentration, as shown by multivariate analysis. 5. The changes in free serum percentages of isradipine and darodipine were inversely related to concomitant changes in the concentration of the serum protein for which they showed the highest affinity, AAG for isradipine and HSA for darodipine, respectively. 6. The unexplained variability in the binding data was greater when AAG was the major determinant of binding (isradipine).
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PMID:Differences in the serum binding determinants of isradipine and darodipine--consequences for serum protein binding in various diseases. 253 7

The relationship between the serum protein binding of carbamazepine (CBZ) and carbamazepine-10,11 epoxide (CBZ-E) and the concentration of alpha 1-acid glycoprotein (AAG) and albumin (HSA) was examined in 39 CBZ-treated epileptic children aged 4 months to 12 years. A significant inverse correlation was found between the free fraction of both compounds and serum AAG, even though changes in AAG concentration explained only part of the variation in binding. No correlation was found between the free fraction of CBZ and CBZ-E and HSA, probably due to the small intersubject variation in HSA concentration. In vitro experiments showed that both CBZ and CBZ-E were bound to HSA and to a lesser extent to AAG. At equivalent HSA concentrations, the binding of CBZ and its metabolite increased proportionately with increasing AAG concentration within the range occurring clinically.
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PMID:Alpha 1-acid glycoprotein concentration and serum protein binding of carbamazepine and carbamazepine-10,11 epoxide in children with epilepsy. 407 20

An adsorption technique with polydimethylsiloxane-coated glass beads (PDMS-GB) was developed to determine the protein binding of a highly lipophilic and hydrophobic drug. The present assay method is based on the quantitative adsorption of unbound drug to the PDMS-GB. This method of batch separation in a glass assay tube has an advantage of simplicity and rapidity. To evaluate the reliability of PDMS-GB assay, we compared the protein binding of diazepam in serum in-vitro measured by ultrafiltration and PDMS-GB assay. There was no significant difference between the extent of binding measured by each method. Using PDMS-GB assay, we determined the protein binding of the prostaglandin I2 (PGI2) analogue isocarbacyclin methyl ester (TEI-9090), whose binding cannot be measured by commonly employed techniques (equilibrium dialysis, ultrafiltration, gel filtration or ultracentrifugation) because of a high degree of adsorption to membranes, resins or tubes. The percentage of TEI-9090 bound in human serum, 4% human serum albumin (HSA, fatty acid-free) and dog serum were approximately 98, approximately 87 and approximately 95%, respectively, and these values were independent of TEI-9090 concentration up to 10 ng mL-1. The binding of isocarbacyclin (TEI-7165) to serum protein in man, dogs, rabbits and rats, determined by ultrafiltration, was also high (> 90%). While the displacement of TEI-9090 and TEI-7165 binding to HSA by aspirin, salicylic acid and indomethacin was not observed, clofibric acid and free fatty acids significantly inhibited the protein binding of both compounds.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Determination of protein binding of a highly lipophilic drug, isocarbacyclin methyl ester (TEI-9090), using a polydimethylsiloxane-coated glass beads assay. 769 73

The serum protein binding of itraconazole and fluconazole, new azole antifungal agents, has been investigated in vitro, in serum from healthy volunteers and from patients with cancer. Protein binding was determined by ultrafiltration. Concentrations of both alpha 1-acid glycoprotein (AAG) and albumin (HSA) were measured in all serum samples. The serum protein binding of itraconazole was reduced in patients (96.02 +/- 1.41% vs 97.25 +/- 0.54%; p < 0.01) with respect to healthy volunteers. In contrast, fluconazole protein binding was increased in the same group of patients (22.96 +/- 3.60% vs 13.30 +/- 2.58%; p < 0.01). HSA levels in cancer patients were significantly decreased (p < 0.01) and AAG levels were found to be significantly elevated in patients with respect to control subjects (p < 0.05). A significant linear relationship between the bound/unbound concentration ratio of itraconazole and HSA (r2 = 0.3340; p < 0.01) was found. Similarly, a significant relation was established between the bound/unbound concentration ratio of fluconazole and AAG levels (r2 = 0.2235; p < 0.05). Thus, a weak association between the binding of these drugs and serum protein levels has been observed. It is concluded that both antifungal drugs show different protein binding behaviour in cancer patients.
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PMID:Protein binding of itraconazole and fluconazole in patients with cancer. 855 24

The changes in plasma cortisol levels, immune response parameters and growth of juvenile Atlantic salmon (Salmo salar) were monitored during a 50 days period following a DNP-HSA (di-nitrophenyl human serum albumin) immunisation program. Antibody titers rose significantly after a single immunisation. An increased plasma cortisol concentration was observed in association with injection of both antigen and saline. A single injection had a significant negative effect on growth of fish and fish subjected to 2 injections with a 25 days interval had an even larger growth reduction. The plasma cortisol concentration and the specific antibody response were compared at an individual level but no correlation was found. Total serum protein increased during the experimental period independently of immunisation. In contrast the total serum immunoglobulin 50 days after the first immunisation was clearly connected to antigen exposure. The observations are discussed in relation to immunophysiological changes during immunisation and stress induction.
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PMID:Association between immunisation, reduced weight gain and plasma cortisol concentrations in juvenile Baltic salmon (Salmo salar). 944 81

The present report describes application of advanced analytical methods to establish correlation between changes in human serum proteins of patients with coronary atherosclerosis (protein metabolism) before and after moderate beer consumption. Intrinsic fluorescence, circular dichroism (CD), differential scanning calorimetry and hydrophobicity (So) were used to study human serum proteins. Globulin and albumin from human serum (HSG and HSA, respectively) were denatured with 8 m urea as the maximal concentration. The results obtained provided evidence of differences in their secondary and tertiary structures. The thermal denaturation of HSA and HSG expressed in temperature of denaturation (Td, degrees C), enthalpy (DeltaH, kcal/mol) and entropy (DeltaS kcal/mol K) showed qualitative changes in these protein fractions, which were characterized and compared with fluorescence and CD. Number of hydrogen bonds (n) ruptured during this process was calculated from these thermodynamic parameters and then used for determination of the degree of denaturation (%D). Unfolding of HSA and HSG fractions is a result of promoted interactions between exposed functional groups, which involve conformational changes of alpha-helix, beta-sheet and aperiodic structure. Here evidence is provided that the loosening of the human serum protein structure takes place primarily in various concentrations of urea before and after beer consumption (BC). Differences in the fluorescence behavior of the proteins are attributed to disruption of the structure of proteins by denaturants as well as by the change in their compactability as a result of ethanol consumption. In summary, thermal denaturation parameters, fluorescence, So and the content of secondary structure have shown that HSG is more stable fraction than HSA.
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PMID:Structure characterization of human serum proteins in solution and dry state. 1190 9

The activation of T lymphocytes upon antigen stimulation plays a crucial role in adverse immune responses including drug-specific hypersensitivity reactions. The helpfulness of conventional tritiated thymidine incorporation assay for penicillin allergy diagnostics is limited. Benzylpenicillin, as a reactive compound, constitutes typical example of hapten. Most of research on penicillin hypersensitivity use benzylpenicillin-albumin (BPO-HSA) conjugates. Thus in this study we describe an in vitro proliferation assay with benzylpenicillin or penicillin and autologous serum protein conjugates. Interestingly these conjugates enhanced incorporation of tritiated thymidyne, when benzylpenicillin did not exert an influence on PBMCs proliferation (correlation coefficient r = -0.0119). This so-called carrier-effect indicates that benzylpenicillin and serum globulin complexes can take part in penicillin allergy (primary immune response). Optimal secondary response is obtained when the benzylpenicillin bind the same carrier for both primary and secondary immunization. Father-proliferation assay with modification of responses to phytohaemagglutinin by benzylpenicilloilated serum protein results in significant decrease of incorporation of [3H] thymidyne. Otherwise benzylpenicillin did not modify postmitogenic proliferation of PBMCs. Our findings indicate that the use of penicillin and autologous serum protein conjugates is helpful. This study show the manner in which benzylpenicillin forms T-cell epitopes.
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PMID:[Difficulties with using T lymphocyte culture as a method for diagnosing allergies to benzylpenicillin]. 1204 20

Purification of proteins based on immunoaffinity has been performed using a solid support coated with antibody against the target proteins. The method requires immobilizing the antibody onto the solid support using protein A or G, and has a risk of adsorptive loss of target proteins onto the solid support. Centrifugal precipitation chromatography has been successfully used to purify enzymes, such as ketosteroid isomerase and hyaluronidase without the use of solid support. The purpose of this study is to demonstrate that immunoaffinity centrifugal precipitation chromatography is capable of isolating an antigen by exploiting antigen-antibody binding. The separation was initiated by filling both channels with 40% saturated ammonium sulfate (AS) of pH 4-4.5 followed by loading 20 microl of human plasma (National Institutes of Health blood bank) mixed with 2 mg of rabbit anti-HSA (human serum protein) antibody (Sigma). Then, the sample channel was eluted with water at 0.03 ml/min and AS channel with 40% AS solution of pH 4-4.5 at 1 ml/min until all non-binding components were eluted. Then, the releasing reagent (50% AS solution containing 0.5 M glycine and 10% ammonium hydroxide at pH 10) was introduced through the AS channel to release the target protein (HSA). The retained antibody was recovered by eluting the sample channel with water at 1 ml/min. A hollow fiber membrane device at the outlet (MicroKros, Spectrum, New Brunswick, NJ, USA) was provided on-line dialysis of the eluent before fractions were collected, so that the fractions could be analyzed by SDS-PAGE (sodium dodecyl sulfate - polyacrylamide gel electrophoresis) without further dialysis. The current method does not require immobilizing the antibody onto a matrix, which is used by the conventional immunoaffinity chromatography. This method ensures full recovery of the antigen and antibody, and it may be applied to purification of other proteins.
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PMID:Immunoaffinity centrifugal precipitation chromatography. 1741 78


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