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)

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

Separations of the stereoisomers of a series of tetracyclic and pentacyclic vinca alkaloid analogues having two or three chiral centres were performed on Chiral-AGP and Chiral-HSA high-performance liquid chromatographic columns. Phosphate buffers with pH 5-7 containing 5-35% acetonitrile or 2-propanol were used as mobile phases. The results were in accordance with previous binding data obtained with native AGP and on an HSA-Sepharose column. Whereas on Chiral-AGP the retention of the trans isomers having 1(R),12b(S)-indolo[2,3-a]quinolizidine or the corresponding 3(S),16(R)-eburnane absolute configurations was exceedingly high, on Chiral-HSA the trans isomers, independently of their absolute configurations, were more retained. Eburnane-type compounds could also be separated according to the configuration of the chiral centre at position 14. A comparison of the chromatographic properties of the vinca alkaloids on the Chiral-AGP and Chiral-HSA columns demonstrates that these compounds are bound with higher affinity to the AGP phase. The AGP column resolves a very broad range of vinca alkaloids compared with the HSA column. Higher stereoselectivity and a much better chromatographic performance were also obtained on the Chiral-AGP column.
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PMID:Chiral high-performance liquid chromatographic separations of vinca alkaloid analogues on alpha 1-acid glycoprotein and human serum albumin columns. 143 41

As an advanced stage of glycation, glycated human serum albumin (G-HSA; glucose content, 2 mol of 5-hydroxymethylfurfural equivalent/mol of HSA) was incubated at 37 degrees C up to 30 d in 0.2 M phosphate buffer, pH 7.4, with 100 microM Fe3+. G-HSA incubated for 30 d (G-HSA-30(Fe)) was subsequently hydrolyzed at 110 degrees C for 24 h in 6 N HCl. In the hydrolysate, N epsilon-carboxymethyllysine (CML) was identified by cochromatography with synthesized CML on an amino acid analyzer. pI of HSA (4.8) shifted to 4.5 in G-HSA. A more acidic fraction, pI 4.3, appeared in G-HSA-30(Fe). CML content (mol of CML/mol of HSA) of HSA and G-HSA was as follows; 0 in HSA, 0.2 in HSA-30(Fe), 0.4 in G-HSA and 1.5 in G-HSA-30(Fe) pI 4.3. The amino acid compositions also changed in lysine, arginine and tyrosine at the advanced stage of the reaction.
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PMID:Identification of the carboxymethyllysine residue in the advanced stage of glycated human serum albumin. 161 83

Single-pulse administration of rhG-colony-stimulating factor (CSF) to neonatal rats was previously demonstrated to induce peripheral neutrophilia and modulate bone marrow (BM) neutrophil storage and proliferative pools (NSP + NPP). In this study, we investigated the prolonged effects of 7 days of rhG-CSF therapy (5 micrograms/kg/per day). Sprague-Dawley newborn rats (less than or equal to 24 hours) were injected intraperitoneally (IP) (daily for 7 days) with rhG-CSF or phosphate-buffered saline/human serum albumin (PBS/HSA). RhG-CSF induced a significant early and late peripheral neutrophilia: 6,905 +/- 1,625 (day 1) and 9,223 +/- 515 microL (day 7) v 1,275 +/- 90/microL (P less than or equal to .0001). In addition, 7 days of rhG-CSF resulted in a significant increase in the BM NSP: 3,247 +/- 190/microL v 1,677 +/- 339/microL (P less than or equal to .001). There was, however, no depletion or significant change in the BM NPP. Seven days of rhG-CSF also induced a mild increase in BM CFU-GM colony formation (P less than or equal to .01). There was, however, no significant change in liver/spleen CFU-GM colonies or in the CFU-GM proliferative rate in either the BM or liver/spleen cultures. Finally, 7 days of prophylactic rhG-CSF therapy resulted in a synergistic response with antibiotic therapy and significantly modulated the mortality rate during experimental group B streptococcal sepsis (GBS) (100% v 50%) (GvsC) (P less than or equal to .001). Pulse rhG-CSF administered at 6 hours or 18 hours after GBS inoculation, however, failed to act synergistically with antibiotics to improve survival or prevent peripheral neutropenia. This study suggests that 7 days of prophylactic rhG-CSF therapy induces peripheral neutrophilia, myeloid maturation, increases neutrophil BM reserves and also may provide immunologic enhancement of neonatal host defense during experimental GBS in term neonatal rats.
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PMID:Seven-day administration of recombinant human granulocyte colony-stimulating factor to newborn rats: modulation of neonatal neutrophilia, myelopoiesis, and group B Streptococcus sepsis. 169 22

The thermal stability of IL-1 beta in aqueous solution as a function of temperature (5-60 degrees C), pH (2-9), buffer (acetate, citrate, tris, and phosphate), and cyroprotectants (sugars, HSA) was investigated in this study. The analytical methodologies included RP-HPLC, SEC, ELISA, IEF-PAGE, SDS-PAGE, and bioassay. The degradation and inactivation of IL-1 beta at or above 39 degrees C were attributed to autoxidation of the two cysteine residues in the denatured protein, followed by hydrophobic/covalent aggregation and precipitation. At or below 30 degrees C, IEF- and SDS-PAGE results suggest a possible deamidation reaction. The difference in mechanism of degradation precludes the prediction of formulation shelf life from accelerated temperature data. Nonetheless, the good stability observed at 5 degrees C suggests that a solution formulation may be feasible for IL-1 beta.
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PMID:Stability of interleukin 1 beta (IL-1 beta) in aqueous solution: analytical methods, kinetics, products, and solution formulation implications. 187 Oct 44

This enzyme immunoassay (EIA) was developed to measure pyridoxal 5'-phosphate bound to albumin (PLP-HSA) in human serum. The monoclonal antibody titer was 1:2000 and a sequential saturation analysis curve, prepared with samples containing from 10 to 1000 nmol/L, showed a 50% inhibition of antibody at 50 nmol of the conjugate per liter. The lower limit of detection for PLP-HSA was 10 nmol/L, a sensitivity 1000-fold greater than that for any potential interferent. When serum samples gave negative results in the assay, we compared the antigenicity of the principal sites for PLP binding on HSA. It was apparent that the preferred physiological site was not antigenic; however, three additional sites for PLP binding on HSA elicited comparable antibody avidity. This EIA is potentially quite sensitive and specific for PLP-HSA, but considerable additional effort is required to convert serum PLP to an HSA-bound form detectable in the assay, which limits its application as a screening method.
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PMID:Monoclonal antibodies evaluated for use in a screening assay for conjugates of human serum albumin and pyridoxal 5'-phosphate. 266 8

We have examined the in-vitro distribution of 7-hydroxymethotrexate (7-OH-MTX), a cytotoxic metabolite of methotrexate (MTX), in human blood, and its protein binding in serum. The distribution of 7-OH-MTX (10(-6) M) in fresh samples of whole blood was studied at 37 degrees C and pH 7.51 +/- 0.05 (mean +/- s.d.), and its protein binding was assessed by equilibrium dialysis of serum against Krebs Ringer phosphate buffer at 37 degrees C and pH 7.41 +/- 0.07 (mean +/- s.d.). 7-OH-MTX had a mean cell/plasma concentration ratio of 0.03 (range 0-0.27, n = 18). It was extensively bound in human serum, with a bound fraction of 90.4 +/- 3.3% (mean +/- s.d.) in healthy volunteers (n = 11), and significantly lower, 82.3 +/- 4.0% (mean +/- s.d.), in hypoalbuminaemic surgical patients (n = 7). The binding of 7-OH-MTX was correlated with serum albumin (HSA) concentrations (r = 0.72, P less than 0.0007, n = 18). Blood distribution data support the contention that 7-OH-MTX has a small volume of distribution, and HSA appears to be mainly responsible for the high degree of its protein binding in serum.
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PMID:Distribution of 7-hydroxymethotrexate in human blood. 289 74

Propranolol binding to isolated human alpha-1-acid glycoprotein (AGP) and human albumin (HSA) was studied by equilibrium dialysis at 37 degrees C. With AGP (0.067%) and HSA (4%), total propranolol concentration was varied from 0.7 to 93,000 ng mL-1. Over this concentration range the percentage drug bound to HSA declined from 49 to 39% while that to AGP declined from 68 to 4%. Two classes of sites were identified on AGP with n1k1 = 8.50 X 10(4) M-1 and n2k2 = 3.12 X 10(4) M-1. With a pH 7.4 phosphate buffer, propranolol binding to AGP was greatest when the protein was initially dissolved in pH 7.4 water compared with pH 7.2 water or the phosphate buffer. Thus, the method of AGP solution preparation affected propranolol binding by this protein. For both AGP and HSA, greater drug binding was noted with phosphate buffers in comparison with a physiological buffer. With phosphate buffers, decreasing pH from 7.4 to 7.0 decreased propranolol binding by AGP, while decreasing pH from 7.7 to 7.4 had little effect. With HSA, the percent propranolol bound consistently decreased on lowering pH from 7.7 to 7.0.
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PMID:Buffer and pH effects on propranolol binding by human albumin and alpha 1-acid glycoprotein. 290 83

The enzymic and non-enzymic formation of protein-arylating intermediates from amodiaquine (AQ,7-chloro-4-(3'-diethylamino-4'-hydroxyanilino) quinoline), an anti-malarial associated with agranulocytosis and liver damage in man, was studied in vitro. [14C]AQ in phosphate buffer, pH 7.4, under air was autoxidized to a reactive derivative(s) which possessed characteristics indicative of a semiquinone/quinone imine: reduction by NADPH and ascorbic acid, conjugation with thiols and irreversible binding to microsomal and soluble proteins. Cysteinyl SH groups were major sites of arylation. Radiolabelled material irreversibly bound to HSA after 24 hr and to human liver microsomes after 4 hr represented 26.5 +/- 1.8% and 31.4 +/- 0.6% (means +/- SD, N = 3) of incubated [14C]AQ (10 microM), respectively. The quinone imine of AQ(AQQI) was synthesized, and displayed the same oxidative and electrophilic reactions as the product(s) of AQ's autoxidation. A water-soluble product formed in buffered solutions of AQ and N-acetylcysteine was identified as an AQ mercapturate by comparison with an adduct prepared from synthetic AQQI. Irreversible binding of [14C]AQ was inhibited by a radical scavenger; this indicated that the semiquinone imine contributed to the binding. Although AQ was extensively de-ethylated by human liver microsomes, oxidation by cytochrome P-450 did not appear to be principally responsible for its activation and irreversible binding in microsomal incubations. AQ was oxidized to protein-arylating intermediates by horseradish peroxidase. It also formed reactive derivatives, possibly N-chloro compounds, in chlorine solutions. These findings indicated that AQ can give rise to chemically reactive species by at least three distinct mechanisms, viz. autoxidation in neutral solution under air, peroxidase-catalyzed oxidation and N-chlorination. Formation of such species in liver and myeloid cells might be responsible for the adverse reactions associated with AQ.
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PMID:Drug-protein conjugates--XIV. Mechanisms of formation of protein-arylating intermediates from amodiaquine, a myelotoxin and hepatotoxin in man. 334 86

Kits were developed for the sterile labelling of macroaggregated albumin (human) with 99mTc. 0.4 mL of 20% HSA, 1 mL of SnCl2 X 2H2O containing 5 mg and 1.1 mL of 0.9% NaCl were sonified for 10 min. The pH was adjusted with phosphate buffer to 5.5 after the addition of 1 mL of 5% Tween-80. The solution was heated with stirring for 10 min at 80 degrees C for aggregation and 1.0 mL portions were placed in 10 mL vials for lyophilization. The contents of single reaction vials were reacted with 99mTc and the radiochemical yield determined (higher than 98%). The MAA kits were stable and the stability of [99mTc]-MAA was followed for 4.5 h. Lung uptake in mice was determined to be about 98.5%. The preparation of [99mTc]-MAA was performed in a single step process and excellent human lung scans were obtained.
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PMID:A new technique for the preparation of ready-to-use macroaggregated albumin (MAA) kits to be labelled with 99mTc for lung scanning. 622 65


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