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)

Two types of changes in the spin-spin relaxation time of water protons (T2) corresponding to the decrease in the correlation time of water molecules have been found in human serum albumin solutions in the temperature range of 20-40 degrees using the NMR method. It follows from experiments with frozen HSA solutions that over 15% of H2O is pushed out from the HSA hydration shell in 10% D2O solution and about 30% of H2O in 20% D2O solution by DOD and DOH molecules. The T2 effects observed increase in the presence of D2O in the protein solution, however, and their maxima shift by 5--10 degrees toward a higher temperature range. An increase in the viscosity of HSA solutions by adding sucrose (20%) results in complete disappearance of the effects. The results were analysed and the conclusion was made that the anomalies observed in T2 result from thermally induced changes in the nature of the relative translational-rotational diffusion of three domains of HSA. Concomitant rapid exchange between the free solvent and water present in the protein cavities between domains can stimulate fluctuations in the solvent and destabilize its structure.
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PMID:Changes in water properties in serum albumin solutions induced by alterations in protein flexibility. NMR studies. 672 50

The immune response of adult rabbits to low concentrations of BSA in their drinking water has been a useful model to study systemic immunity initiated in gut-associated lymphoid tissue. In the present study, this model was applied to neonatal rabbits. 21 New Zealand white neonatal rabbits were fed a cow-milk formula containing 0.17% BSA from the 5th to the 32nd day of life. At this time, anti-BSA was detected in only 5 animals. A subsequent intravenous injection of 50 mg BSA demonstrated a weak anti-BSA response in 6 and complete tolerance in 15 animals. Specificity of this tolerance was demonstrated by a vigorous response to 100 mg HSA, given at 60 days of age, in all of 9 animals tested. At 8 months of age, 2 of 3 animals still failed to respond to intravenous BSA, one rabbit had a low primary-type response. Determination of absorbed antigenic BSA on day 32 showed a mean of 1.09 +/- 0.47 (S.E.) microgram BSA per ml of serum, i.e. a considerably higher concentration than seen in adult animals fed similar antigen concentrations. These observations suggest that orally induced tolerance in neonatal rabbits may be due to an effect on systemic lymphoid tissue following increased antigen absorption rather than a direct antigen effect on gut-associated lymphoid tissue.
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PMID:Induction of specific tolerance to ingested soluble protein in neonatal rabbits. 732 14

Coating of Immulon polystyrene plates with 0.2% casein in phosphate buffered saline (PBS) completely abolishes adsorption of human serum proteins to these plates. However, pretreatment of such plates with PBS or 0.15 M NaCl in deionized water (10 microS) before coating makes possible adsorption of human immunoglobulins G (HIgG) and M but not serum albumin (HSA) and transferrin (HTrf). Effect of pretreatment with PBS on adsorption of HIgG is long-term and rather stable. Results of experiments with radioiodinated HIgG, mouse IgG, HSA and human chorionic gonadotropin confirm the peculiar effect of pretreatment with PBS on casein coating. Pretreatment with deionized water, instead of PBS, markedly diminish adsorption but tap or commercial spring waters (> 1000 microS), even without 0.15 M NaCl, affect adsorption similarly to PBS in deionized water. Super pure water (0.05 microS) even with NaCl used for pretreatment does not influence adsorption of HIgG to plates coated with casein. Distinct differences in adsorption of HIgG and HTrf was demonstrated using solutions for ELISA prepared from super pure, deionized and tap waters.
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PMID:Effect of pretreatment of wells in polystyrene plates on adsorption of some human serum proteins. 750 47

Topotecan, a semisynthetic water-soluble analogue of camptothecin, is the first topoisomerase I targeting anticancer agent to enter comparative phase III clinical trials. Here we elucidate the biophysical factors underlying the markedly improved bloodstream stability and cytotoxic activity of topotecan relative to camptothecin. Each agent contains an alpha-hydroxy-delta-lactone ring that hydrolyzes under physiological pH to yield a biologically-inactive carboxylate form. In human plasma, camptothecin lactone converts rapidly and completely to its carboxylate form due to a 200-fold binding preference by serum albumin (HSA) for the latter [Mi, Z., & Burke, T.G. (1994) Biochemistry 33, 10540-12545]. Time-resolved fluorescence anisotropy measurements reveal that neither topotecan lactone nor carboxylate associates with HSA, thereby resulting in a significantly higher level of lactone stability in plasma for topotecan (t1/2 = 23.1 min, percent lactone at equilibrium of 17.6) relative to camptothecin (t1/2 = 10.6 min, percent lactone at equilibrium of < 0.2). Moreover, studies with HL-60 human promyelocytic leukemia cells reveal that a physiologically-relevant level (40 mg/mL) of HSA dramatically attenuates the cytotoxic activity of camptothecin in excess of 2600-fold (for a 72 h exposure, the IC50 value of 1.5 nM in the absence of HSA increased to 4 microM in the presence of HSA). The activities of other clinically relevant anticancer analogues, 9-aminocamptothecin and SN-38, were also strongly modulated by the presence of 40 mg/mL HSA. In marked contrast, the presence of HSA effected no change on the cytotoxic activity of topotecan (IC50 = 12 nM both in the absence and in presence of HSA).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Reduced albumin binding promotes the stability and activity of topotecan in human blood. 757 64

We covalently coupled 9-beta-D-arabinofuranosyladenine 5'-monophosphate (ara-AMP) to the carrier molecule lactosaminated human serum albumin using a water-soluble carbodiimide with a two-step conjugation method (pH 4.5 and pH 7.5) instead of the commonly used single-step conjugation at pH 7.5. This resulted in a predominantly monomeric conjugate (lac27-HSA-ara-AMP9). The conjugate was stable in buffer (pH 7.4) and blood plasma. After in vivo injection, the carrier and the monomeric conjugate were subjected to selective endocytosis in rat hepatocytes, as shown on immunohistochemical study and cell-separation techniques using 125I-labeled material. In competition experiments with other ligands for the asialoglycoprotein receptor N-acetylgalactosamine and asialofetuin, we showed that both lactosaminated human serum albumin and lac27-HSA-ara-AMP9 are subject to endocytosis by this receptor system. Although the coupling of ara-AMP significantly increased the net negative charge of the conjugate compared with the native carrier, liver uptake was not affected by coadministration of an excess of succinylated human serum albumin (suc-HSA), a negatively charged ligand for the scavenger receptor. Incubation studies with purified rat liver lysosomes showed that in this acidic and proteolytic environment, mainly ara-AMP and, to a much lesser extent, ara-A itself were released from the carrier. After injection into the rat in vivo and in isolated perfused rat liver, no free ara-AMP or 9-B-D-arabinofuranosyladenine (ara-A) could be detected in plasma and perfusate, respectively, indicating proper retention of the virally active components in hepatocytes.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Coupling of the antiviral drug ara-AMP to lactosaminated albumin leads to specific uptake in rat and human hepatocytes. 768 77

A simple and rapid method for the quantitative measurement of mercaptoundecahydrododecarborate (BSH), (which presently is one of the most useful agents for Boron Neutron Capture Therapy) in human plasma was developed by using Fourier transform infrared spectroscopy. Different spacer thicknesses of the liquid sampling cell were examined and the optimal results were obtained by the 0.05 mm spacer. The subtraction of water absorbance from sample spectra resolved a B-H band at 2493 cm-1. The quantitative measurement of BSH was carried out by integration of the B-H band in the wavenumber range of 2534-2440 cm-1. However, at the lower BSH concentration range, a visual inspection of the spectrum to determine the wavenumber range was necessary so as to avoid any negative areas to be integrated. The lower limit of detection of BSH in aqueous solution and human plasma was 5 micrograms ml-1 (about 2.5 ppm of boron).
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PMID:FT-IR measurement of mercaptoundecahydrododecaborate in human plasma. 780 57

Adsorption of albumin (HSA) and fibrinogen (Fib) from human blood plasma onto titanium surfaces with varying oxide properties was studied with an enzyme-linked immunosorbent assay. The intrinsic activation of blood coagulation (contact activation) was studied in vitro using a kallikrein-sensitive substrate. The sample surfaces were characterized with Fourier transform Raman spectroscopy. Auger electron spectroscopy and atomic force microscopy. Low Fib and high HSA adsorption was observed for all titanium samples except for the radio frequency plasma-treated and water-incubated samples, which adsorbed significantly lower amounts of both. Oxide thickness and carbon contamination showed no influence on protein adsorption or contact activation. Smooth samples with a surface roughness (Rrms) < 1 nm showed some correlation between surface wettability and adsorption of Fib and HSA, whereas rough surfaces (Rrms > 5 nm) did not. To varying degrees, all titanium surfaces indicated activation of the intrinsic pathway of coagulation as determined by their kallikrein formation in plasma.
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PMID:Titanium with different oxides: in vitro studies of protein adsorption and contact activation. 798 48

The impact of radio-opaque agents on human blood plasma water pool was studied by using relaxation proton magnetic resonance methods with a pulse gradient of magnetic field. The findings suggest that blood plasma water imbalance was induced by human serum albumin dehydration processes after RCN-HSA interaction.
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PMID:[The effect of iodine-containing x-ray contrast media on water status in the blood plasma]. 820 51

Sequential skin testing including immediate patch test (IPT), skin prick test (SPT), and intradermal test (IT) with sodium benzylpenicillin G (Pen G), and SPT with benzylpenicilloyl human serum albumin (BPO-HSA) was done in 58 subjects with a history of probable anaphylactic reaction or shock of unknown cause. Based on positive skin tests, the diagnosis of penicillin anaphylaxis was confirmed in 30 patients. The average age of onset of penicillin allergy was 42 years ranging from 20-70 years. The sex ratio was 2:28 with marked female predominance. Anaphylactic shock, wheezing and urticaria occurred in 21, 20, 19 patients, respectively. Most symptoms were induced by skin tests and inhalation. The results of skin tests in these patients showed that IPT with 500 U/ml of Pen G was not only reliable but also safe. It is suggested that patients suspected of penicillin anaphylaxis should received IPT with 500 U/ml of Pen G as the initial diagnostic step; if a negative reaction occurred, then SPT and IT should be applied with the same concentration of Pen G, until a positive reaction developed or all the skin testing showed negative results. SPT to BPO-HSA was safe, but its positive rate was only 47.8% in our study; it seems to be less important than skin test to Pen G. As a whole, the skin testing procedure we recommend is relatively reliable, safe and practical even in individuals extremely sensitive to penicillin. In addition, once the patient develops a positive IPT, Pen G residue on the testing site should be wiped away rapidly and washed out with cool water thoroughly to disrupt further violent reaction.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Skin testing in patients with high risk of anaphylactic reactions to penicillin. 821 54

Effective thermodynamic parameters of activation of label transition between two microsurroundings in water-protein matrix (WPM) of spin-labelled molecules of serum albumin (HSA-SL) in 0.001 M phosphate buffer, pH 7.3 within concentration range of NaCl (m3) (10(-3) M to 2 M and concentration range of protein (m2) 50 to 200 mg/ml were determined. The phase transition (PT) between two structures of water in WPM is revealed within the m3 range 0.01 M to 0.1 M. It is close to the type I PT and more expressed at high protein concentrations. As m3 increases (to 0.2 M when m2 = 50 mg/ml and to 0.7 when m2 = 200 mg/ml) PT-I is transformed into PT of the critical type. This is indicated to zero values of the higher order derivatives of Gibbs energy of activation with respect to salt concentration, as well as by the maximum values of positive disjoining pressure in these points. The biological significance of this phenomenon is discussed.
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PMID:[Salt-induced critical type phase transition in a water-protein matrix of serum albumin molecules]. 836 60


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