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Osuntokun J, Onwudiwe DC, Ebenso EE. Aqueous extract of broccoli mediated synthesis of CaO nanoparticles and its application in the photocatalytic degradation of bromocrescol green. IET Nanobiotechnol 2018; 12:888-894. [PMID: 30247126 PMCID: PMC8676217 DOI: 10.1049/iet-nbt.2017.0277] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 03/09/2018] [Accepted: 04/06/2018] [Indexed: 08/03/2023] Open
Abstract
CaO nanoparticles have been prepared using CaCl2 and aqueous extract of broccoli as a precursor and reducing agent, respectively. Different volumes of the aqueous broccoli extract were utilised to obtain Ca(OH)2 and subsequent calcination gave CaO nanoparticles. The synthesised CaO was confirmed by powder X-ray diffraction (XRD). The morphology was studied using transmittance electron microscopy (TEM), and the surface composition of Ca(OH)2 was explored using Fourier transform infrared spectroscopy. The major functional groups present in the capping material responsible for the reduction of the metal salt and the surface passivation of Ca(OH)2 were identified. The XRD pattern revealed cubic phase for all the CaO nanoparticles, and the crystallite size was estimated using Scherrer's equation showed a variation which is dependent on the volume of the extract used. TEM analysis showed different shapes, while the selected area electron diffraction (SAED) results confirmed the crystallinity of the nanoparticles. Thermogravimetric analysis of Ca(OH)2 showed the decomposition product to be CaO. Sample C3, which has the smallest particle size, was used as a catalyst for the degradation of bromocresol green via photo irradiation with ultraviolet light and the result revealed a degradation efficiency of 60.1%.
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Affiliation(s)
- Jejenija Osuntokun
- Faculty of Natural and Agricultural Science, Material Science Innovation and Modelling (MaSIM) Research Focus Area, North-West University (Mafikeng Campus), Private Bag X2046, Mmabatho, South Africa
| | - Damian C Onwudiwe
- Faculty of Natural and Agricultural Science, Material Science Innovation and Modelling (MaSIM) Research Focus Area, North-West University (Mafikeng Campus), Private Bag X2046, Mmabatho, South Africa.
| | - Eno E Ebenso
- Department of Chemistry, Faculty of Natural and Agricultural Science, School of Physical and Chemical Sciences, North-West University (Mafikeng Campus), Private Bag X2046, Mmabatho, South Africa
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Huang X, Guo S, Wang W. Effects of minimally invasive puncture and drainage of intracranial hematoma on the blood-brain barrier in patients with cerebral hemorrhage. J Huazhong Univ Sci Technolog Med Sci 2007; 27:101-3. [PMID: 17393122 DOI: 10.1007/s11596-007-0128-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2006] [Indexed: 05/14/2023]
Abstract
The effects of minimally invasive surgery on the blood-brain barrier (BBB) of 30 patients with cerebral hemorrhage were investigated. Difference of the BBB index and serum MBP concentration were assessed in 15 cases of conservative treatment group and 15 cases of minimally invasive surgery group. The BBB index in minimally invasive surgery group was significantly lower than in conservative treatment group (P<0.05), and the BBB index in the two treatment groups was significantly higher than in control group (P<0.01). Serum MBP concentration in minimally invasive surgery group was significantly lower than in conservative treatment group (P<0.05), and that in the two treatment groups was significantly higher than in control group (P<0.01). It was suggested the permeability of BBB in patients with cerebral hemorrhage was increased, and BBB index and serum MBP concentration in patients with cerebral hemorrhage were increased. Minimally invasive surgery can reduce the lesion of cytotoxicity to BBB and cerebral edema.
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Affiliation(s)
- Xiaojiang Huang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
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Trivedi VD, Saxena I, Siddiqui MU, Qasim MA. Interaction of bromocresol green with different serum albumins studied by fluorescence quenching. Biochem Mol Biol Int 1997; 43:1-8. [PMID: 9315276 DOI: 10.1080/15216549700203751] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The binding of bromocresol green to bovine serum albumin at micromolar concentrations leads to quenching of protein fluorescence. This property has been used here to study interaction of bromocresol green with bovine serum albumin as a function of pH and ionic strength. The transformation of fluorescence quench data obtained with bromocresol green into Scatchard plots yielded an association constant of 3.06 x 10(7) 1 M-1 and a binding capacity of about 1.0. The affinity of bromocresol green for bovine serum albumin remains virtually unchanged between pH 4.0 and 8.0 but decreases by about 7 fold with increase in ionic strength from 0.01 to 1.0. Six other serum albumins obtained from cat, dog, human, pig and sheep have also been studied for bromocresol green binding. Although all the albumins studied bind bromocresol green, they show considerable differences in their affinities towards the dye. It appears that despite a great degree of overall similarity in their structure and conformation, serum albumins from different species differ in their ligand binding properties.
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Affiliation(s)
- V D Trivedi
- Department of Biochemistry, J.N. Medical College, A.M.U., Aligarh, India
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Abstract
Bromcresol green (BCG) assay has been used in microvascular studies to determine albumin in rat plasma. The purpose of this study was to demonstrate that BCG overestimates rat plasma albumin partly because BCG binds to transferrin, a beta-globulin. The light absorbance of a transferrin-BCG reagent solution is shown to increase with time; appreciable binding occurs within a few seconds. Pure transferrin produced BCG assay results (P less than 0.001) that could be expressed as pseudoalbumin concentrations. Albumin and transferrin solutions of equal concentrations were mixed in equal parts; a plot of albumin concentration determined by BCG vs. actual albumin concentration had a slope greater than the expected value of 1.0 (P less than 0.001). Plasma samples were obtained from six rats and assayed for albumin. Electrophoresis yielded a plasma albumin of 2.97 +/- 0.11 g/dl, whereas BCG assay yielded a significantly (P less than 0.01) greater value of 3.58 +/- 0.07 g/dl. We conclude that BCG assay estimates of albumin-to-globulin ratio (A/G), in which G is determined from the difference between total protein and albumin, are especially subject to error.
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Affiliation(s)
- B J Barber
- Department of Physiology, Medical College of Wisconsin, Milwaukee 53226
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Watkins JB, Noda H. Biliary excretion of organic anions in diabetic rats. J Pharmacol Exp Ther 1986; 239:467-73. [PMID: 2430094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Little definitive data are available concerning the effects of insulin deficiency on the hepatic uptake and biliary excretion of endogenous or xenobiotic substances. To expand our understanding of this area, male Sprague-Dawley rats were pretreated with streptozotocin (45 mg/kg i.v.) to induce uncontrolled diabetes. Four to five weeks later, diabetic rats exhibited elevations in serum glucose (640 +/- 13 mg/dl), biliary glucose (307 +/- 35 mg/dl), urine output (166 +/- 11 ml/24 hr), basal bile flow rate (73 +/- 2 microliter/min/kg), liver weight/body weight ratio and bile acid pool size. Polyphagia and generalized muscle atrophy were also evident. Plasma disappearance and biliary excretion of several organic anions were studied after i.v. administration. There were no differences between control and diabetic rats in the plasma elimination and biliary excretion of eosin, phenol-3,6-dibromphthalein disulfonate and sulfobromophthalein. Although hepatic uptake was unchanged, the biliary excretion of amaranth was decreased 30% in diabetic rats. There were no differences in bile flow rate in control or diabetic rats after administration of these four anions. In contrast, administration of indocyanine green, bromcresol green and rose bengal did not depress bile flow in diabetic rats as was observed in control rats. In addition, the rate of maximal biliary excretion was increased by 390, 240 and 151% for rose bengal, indocyanine green and bromcresol green, respectively. Plasma clearance of rose bengal was 65% higher in diabetic rats. Total body clearance and steady-state volume of distribution values for all other anions were not different after induction of diabetes.(ABSTRACT TRUNCATED AT 250 WORDS)
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Calvo R, Carlos R, Erill S. Underestimation of albumin content by bromocresol green, induced by drug displacers and uremia. Int J Clin Pharmacol Ther Toxicol 1985; 23:76-8. [PMID: 3988397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Phenylbutazone and clofibric acid, two drugs strongly bound to human albumin, produce low readings of albumin content in serum when the bromocresol green immediate reaction is used. This abnormality is observed at drug concentrations within the range obtained during therapeutic use, and tends to be more marked in diluted samples of serum. Abnormally low values of albumin content are also obtained when the bromocresol green method is used in uremic sera, and the disparity seems related to the degree of carbamylation of these samples. The reported interferences are great enough in some cases as to suggest that the use of the immediate reaction between bromocresol green and serum should not be considered a valid measure of albumin content when these factors cannot be totally excluded.
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Nilova NS. [Sorption of sulfophthaleinic dyes by the brain synaptosomes of rats deprived of parodoxical sleep]. Tsitologiia 1984; 26:1396-400. [PMID: 6528362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The influence of paradoxical sleep deprivation on sorption of bromphenol blue, bromcresol green and bromthymol blue by rat's brain synaptosomes was studied. Effect of sleep disturbance (increase in the number of dye bindings) was shown to augment with the increase in hydrophobicity of the sulfophtaleinic dye.
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Abstract
In human medicine it has been shown that the bromocresol green (BCG) dye-binding method for the determination of serum albumin is not entirely specific, the dye reacting also with certain human serum globulins. This causes over-estimation of albumin when reaction times are prolonged beyond 30 seconds. In the present study, serum albumin values obtained from three animal species by the "immediate", i.e. less than 30 seconds, BCG reaction were compared with those by the 10-minute BCG reaction. Albumin-depleted sera were prepared using an affinity chromatography technique and their reactions and those of purified gamma globulin preparations with the dye were studied. In cattle, sheep and horses, serum albumin values obtained by the 10-minute reaction were higher than those obtained by the "immediate" BCG reaction, the differences being statistically significant. Purified gamma globulin did not react with the BCG dye after 10 minutes, but other globulins did. There were differences between the species in the magnitude of the reaction of their globulins with BCG dye.
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Fischer E, Gregus Z, Varga F. Effects of cobalt chloride and cycloheximide on the hepatic microsomal enzyme system and biliary excretion rate in control and phenobarbital-pretreated rats. Arch Int Pharmacodyn Ther 1983; 262:180-8. [PMID: 6870392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Graffi A. [Selective, time dependent accumulation of the triphenylmethane dyes bromphenol blue, bromoresol green and iodophenol blue in mouse tumors]. Z Exp Chir 1981; 14:325-335. [PMID: 7340260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
1. A selective late dye concentration dependent on the time is described for 3 triphenylmethane dyes namely bromphenol blue, bromcresol green and iodophenol blue after intravenous application in high dosage in malignant inoculated tumors and experimental tumor metastases in the mouse. 2. The possible mechanisms of this dye concentration phenomenon in the tumor tissue as well as some chances of the eventual therapeutic and tumor diagnostic utilization were discussed.
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Bowmer CJ, Lindup WE. Inverse dependence of binding constants upon albumin concentration. Results for L-tryptophan and three anionic dyes. Biochim Biophys Acta 1980; 624:260-70. [PMID: 6893287 DOI: 10.1016/0005-2795(80)90245-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The interactions of methyl orange, bromocresol green, 2-(4'-hydroxybenzeneneazo)benzoic acid (HABA) and L-tryptophan with human albumin at pH 7.4 were investigated by equilibrium dialysis at 37 degrees C. Binding characteristics of each of the three dyes were studied by two approaches: (1) variation of total ligand concentration with a single albumin concentration and (2) variation of albumin concentration with a single total ligand concentration. Both approaches gave typical Scatchard plots with negative slope for methyl orange and bromocresol green, with good agreement between the two sets of data for each dye. In contrast, approach (2) gave Scatchard plots with a positive slope for HABA and L-tryptophan, indicating a decrease in the number of binding sites (n) and/or association constant (k) as the albumin concentration increased. This inverse dependence of nk upon albumin concentration for 2-(4'-hydroxybenzeneazo)benzoic acid was mainly due to changes in n which were still observed in the presence of inhibitory chloride ions at pH 5.75. Reasons for this type of binding behaviour are discussed together with general implications for binding studies. The results show 2-(4'-hydroxybenzeneazo)benzoic acid to be a useful ligand for investigation of this problem.
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L'vova EB, Movchan IR, Shcherbakova EI, Smirnov VA. [Primary selection method for microorganism producers of organic acids]. Mikrobiologiia 1980; 49:323-5. [PMID: 6993885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A method is suggested for primary selection of microorganisms producing organic acids. The methods is based on the use of diagnostic media containing the indicator bromocresol green. When yeast fungi of various taxonomic groups were grown in indicator media, 49 yeast cultures producing organic acids were found. Among these, 38 cultures accumulated from 5.0 to 30.0 mg% of citric acid when grown in a medium containing n-paraffins.
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Varga F, Málly J, Fischer E. Effect of insulin on the biliary excretion of some organic anions in rats. Arch Toxicol Suppl 1980; 4:391-3. [PMID: 7002105 DOI: 10.1007/978-3-642-67729-8_86] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In rats insulin enhanced the biliary excretion of rose bengal (50 mg/kg) and bromcresol green (25 mg/kg), and raised the depressed bile flow caused by these organic anions. There was, however, no parallelism between the choleretic effect of insulin and the increase in biliary transport of the two dyes.
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Fischer E, Gregus Z. Time course of the effects of phenobarbital on biliary flow and on the biliary excretion of bromcresol green in rats. Acta Med Acad Sci Hung 1980; 37:321-327. [PMID: 7457033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Biliary flow and the biliary excretion of bromcresol green were measured in rats injected i.p. with a single dose of phenobarbital, 75 mg/kg. Biliary flow began to increase 6 h after the injection, it reached a peak at 36 h and returned to the control level at 72 h. In the same rats, the enhanced biliary excretion of bromcresol green was first observed at 12 h, it reached a peak at 24 h and returned to the control level at 72 h. Other groups of rats received 75 mg/kg phenobarbital as daily i.p. dose over 5 days. In these groups, the increase in biliary flow did not exceed that measured in the rats given the single dose, however, the biliary excretion of bromcresol green reached its peak after a 4-day phenobarbital treatment. After the 5th day of treatment the biliary flow and the biliary excretion of bromcresol green remained significantly stimulated for 4 days and the changes in these parameters regressed on the fifth day following the last injection of phenobarbital. The changes in liver weight appeared not to run closely parallel either with the increase in biliary flow or with the enhancement of biliary excretion of bromcresol green. It is suggested that the changes in biliary flow and in the biliary excretion of bromcresol green take place by different mechanisms after phenobarbital administration.
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Fischer E, Gregus Z, Varga F. Effects of barbiturates on the hepatic cytochrome P-450 dependent enzyme system and biliary excretion of exogenous organic anions in rats. Digestion 1980; 20:115-20. [PMID: 6767638 DOI: 10.1159/000198428] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Effect of pretreatment (150 mumol/kg i.p. twice daily for 5 days) wtih six barbiturates (barbital, butobarbital, pentobarbital, amobarbital, phenobarbital and thiopental) on the hepatic microsomal drug methabolizing enzyme system and biliary excretion of bromcresol green and bromsulphthalein-glutathione conjugate has been investigated in rats. All six barburates produced microsomal induction. Phenobarbital, thiopental, barbital and butobarbital increased liver weight, biliary flow and biliary excretion of bromcresol green and bromsulphthalein-glutathione conjugate, however, pentobarbital and amobarbital were ineffective in these parameters. Our results seem to indicate that the enhanced biliary excretion of exogenous anions produced by barbiturates is independent of microsomal enzyme induction.
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Abstract
Bile flow and the biliary excretion of indocyanine green, bromcresol green, eosine, bromsulphthalein-glutathione conjugate (BSP-GSH), amaranth and iodoxamic acid were investigated in control and phenobarbital-pretreated rats (75 mg/kg i.p. daily for 5 days). The bile flow was increased by phenobarbital from an average of 50.6 to 77.7 microliter/kg/min. Depending on the dose, the biliary excretion rate of bromcresol green was increased by 48-496% and that of eosine by 30-149%. After phenobarbital pretreatment the excretion of BSP-GSH was also enhanced by 34-52%, that of amaranth by 37-53% and that of iodoxamic acid by 40-56%. However, the biliary excretion of indocyanine green remained unchanged. There was no parallelism between the increase in bile flow and biliary excretion of the drugs.
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Yap W, Schaffer R. Binding of dye to albumin, as studied by ultrafiltration. Clin Chem 1977; 23:986-9. [PMID: 858205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We describe a procedure for measuring the binding of small molecules to proteins by means of a dynamic ultrafiltration system. A continuous binding curve is obtained by continuously monitoring the absorbance of ultrafiltrate as a function of ultrafiltrate volume, and corrections are made for the retention of the small molecule by the membrane and the leakage of the protein through the membrane. The method is applied to the binding of bromcresol green to human albumin. Some major sources of uncertainties in the method are discussed.
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Abstract
Fetal and adult bovine serum albumin were purified by standard techniques and then treated with activated charcoal at pH 2.75 to remove small molecular weight legands. The two proteins were compared and found to be identical by the following criteria: isoelectric focusing, electrophoresis on cellulose acetate and polyacrylamide gel, by the binding of bromcresol green, salicylic acid, diphenylhydantoin, and six different fatty acids (palmitic, stearic, oleic, elaidic, linoleic, and arachidonic). Reports of marked differences in the capacities of fatal and ault plasma to bind bilirubin and various drugs have usually been attributed to the presence of a "fetal" albumin. Our results, however, are consistent with the view that there is no difference between adult and fetal albumin and that the observed altered binding properties of fetal plasma are due to the tight binding of a ligand to fetal albumin in blood, which modifies the protein's affinity for lipophilic compounds.
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Sheikh MI. Renal handling of phenol red. II. The mechanism of substituted phenolsulphophthalein (PSP) dye transport in rabbit kidney tubules in vitro. J Physiol 1976; 256:175-95. [PMID: 933027 PMCID: PMC1309299 DOI: 10.1113/jphysiol.1976.sp011319] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
1. The uptake of various substituted phenolsulphophthalein dyes by cortical slices of rabbit kidney has been studied in detail in order to obtain more information on the secretory system for organic anions. 2. The rate of initial uptake of dyes and the accumulation after incubation for 2 hr under aerobic conditions increased in the order: phenol red (PR) greater than bromophenol blue (BPB) greater than bromocresol green (BCG) greater than bromothymol blue (BTB), while the reverse order of uptake was observed under anaerobic conditions. There was no difference between the uptake of BTB under aerobic and anaerobic conditions. 3. The accumulation of dyes under anaerobic conditions could be accounted for by binding to tissue constituents. In comparison with PR (Sheikh, 1972), the substituted dyes were found to interact extensively with the 700 G (cell membranes) and cytosol fractions of renal homogenates. 4. Low concentrations of the substituted dyes efficiently inhibited the accumulation of rho-aminohippurate (PAH). The concentration of dye resulting in 50% inhibition of PAH accumulation (KI) agreed well with concentrations estimated to sustain 50% of maximal dye transport (KM). On this basis the affinity of the dyes for the transport system increases in the order: PR less than BPB less than BCG less than BTB. 5. Probenecid, 2,4-dinitrophenol, PAH, octanoate and succinate affected to a smaller extent the uptake and binding of BPB and BCG by renal tissue than that previously shown for PR (Sheikh, 1972). No inhibitory effect of these substances on the accumulation of BTB by kidney tissue was observed. 6. The binding of PSP dyes by phospholipid vesicles (liposomes) and a representative binding protein, human serum albumin, exhibited close similarity to that of binding by renal tissue. Partition experiments involving octanol-water phases indicated that the hydrophobicity of the dyes increased in the order: PR less than BPB less than BCG less than BTB. 7. The results indicate that BTB, despite its inhibitory potency, is not transported by the organic anion system. BPB and BCG are transported to a lesser extent, and interact more strongly with the transport system than does PR. It is suggested that the substituted dyes by virtue of hydrophobic interaction with the transport system reduce the movement of the mobile part of the transport system.
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Reed RG, Feldhoff RC, Clute OL, Peters T. Fragments of bovine serum albumin produced by limited proteolysis. Conformation and ligand binding. Biochemistry 1975; 14:4578-83. [PMID: 1237311 DOI: 10.1021/bi00692a004] [Citation(s) in RCA: 225] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Twelve fragments of bovine serum albumin, isolated following limited tryptic or peptic hydrolysis, have been studied to define secondary structure and locate ligand-binding sites. Based on circular dichroism, the conformational pattern of albumin (68% alpha helix and 18% beta structure) is substantially retained by individual fragments, indicating that secondary configuration is locally determined and is not destroyed during the cleavage process nor during fragment purification. The strong bilirubin-binding site of bovine serum albumin is present in 3 of the 12 fragments. Residues 186-238 are common to the three fragments and absent from those fragments which do not bind bilirubin; consequently the strong bilirubin-binding site is suggested to involve this region. By similar reasoning, the presence of palmitate-binding sites in some fragments and not in others indicates that the three strongest sites for the binding of palmitate are located in the carboxyl-terminal two-thirds of the molecule. The first site (KA approximately 2 X 10(7) M-1) is suggested as residues 377-503; the second site (KA approximately 8 X 10(6) M-1), residues 239-306; the third site (KA approximately 2 X 10(6) M-1), residues 307-377. Bromocresol Green, a reagent used in the assay of ablumin, was bound by fragments rougly in proportion to their size but showed particular affinity for the region of the strong bilirubin-binding site. The fluorescent probe, 8-anilino-1-naphthalensulfonate, was in general bound by large fragments, supporting the concept that this ligand is held principally in clefts between domains of the macromolecule.
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Clark AG, Rogers KM. Dependence upon bile volume of the biliary excretion of bromocresol green and amaranth in the anaesthetized rat. Aust J Biol Sci 1975; 28:339-51. [PMID: 1191126 DOI: 10.1071/bi9750339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The kinetics of the biliary excretion of both bromocresol green and amaranth are better described in terms of rate equations that are functions of the cumulative volume of bile excreted rather than of time. The rate of disappearance of bromocresol green from the liver also appears to depend on the volume of bile excreted rather than on time. It is proposed that bromocresol green, and probably also amaranth, rapidly equilibrates between the hepatic and biliary compartments as a result of reabsorption from the biliary tree and that the rate-limiting factor in the biliary excretion of these dyes is the removal of dye from the biliary tree by bulk flow. Six methods for the graphical presentation of excretion data are examined and their use in the characterization of the kinetics of an excretion system is discussed.
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