Disk-Sphere Transformation in Mammalian Red Cells

1940 ◽  
Vol 17 (2) ◽  
pp. 117-127
Author(s):  
ROBERT F. FURCHGOTT ◽  
ERIC PONDER
Keyword(s):  
Fatty Acid ◽  
Cell Surface ◽  
Serum Albumin ◽  
Blood Cells ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Red Cells ◽  
Red Cell ◽  
Buffer Solution ◽  
Ph Values

1. Experimental evidence has been presented showing that crystalbumin (the carbohydrate-poor fraction of serum albumin) is the factor which prevents mammalian red blood cells from becoming spherical at pH values over 9.2. 2. The amount of crystalbumin taken up from a solution of it by red cells previously freed of it is of the order of 800 mg. per 100 c.c. of red cells. If this amount is all taken up at the red cell surface, it would form a layer only a few molecules thick. 3. The electrophoretic mobility in phosphate buffer of pH 7.4 is the same for cells containing crystalbumin, cells free of crystalbumin, cells with anti-sphering activity counteracted by fatty acid, and ghosts which have been temporarily sphered by a rise in pH. The mobilities in a saline-glycine buffer solution of pH 10.1 for the first three classes of cells just mentioned are also the same. The mobility of cells sphered with lecithin in a saline-phosphate buffer solution is the same as that for untreated discoidal cells.

Bioceramic Hydroxyapatite Granules for Purification of Biotechnological Products

2011 ◽  
Vol 284-286 ◽  
pp. 1764-1769 ◽  
Author(s):  
Vitalijs Lakevics ◽  
Janis Locs ◽  
Dagnija Loca ◽  
Valentina Stepanova ◽  
Liga Berzina-Cimdina ◽  
...  
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Phosphate Buffer ◽  
Bovine Serum ◽  
Phosphate Buffer Solution ◽  
Sorption Process ◽  
Buffer Solution ◽  
Ph Values ◽  
Bovine Serum Albumin Adsorption ◽  
Albumin Adsorption

Sorption experiments of bovine serum albumin (BSA) on hydroxyapatite (HAp) ceramic granules, prepared at three temperatures 900°C, 1000°C and 1150°C were performed at room temperature 18,6 °C and phosphate buffer, pH 5,83; 6.38 and 7,39. Thermal treatment contributed to the decrease of bovine serum albumin immobilization indicating that sorption process depended on HAp ceramics specific surface area and pH values of phosphate buffer solution. However, it was confirmed that granule size was also an important parameter for bovine serum albumin adsorption. As a result of these experiments, the most appropriate adsorption conditions and phosphate buffer pH values influence on to BSA sorption were analyzed.

scholarly journals Normal Functions of the Spleen Relative to Red Blood Cells: A Review

Blood ◽  
1959 ◽  
Vol 14 (4) ◽  
pp. 399-408 ◽  
Author(s):  
WILLIAM H. CROSBY
Keyword(s):  
Cell Surface ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Normal Function ◽  
Red Cells ◽  
Red Cell ◽  
Cell Production ◽  
Normal Functions ◽  
Normal Spleen ◽  
And Storage

Abstract During all the stages of a red cell’s life the normal spleen exerts a normal function. Eight of these functions have been considered: (1) erythropoiesis; (2) an effect upon red cell production; (3) an effect upon maturation of the red cell surface; (4) the reservoir function; (5) the "culling function"; (6) iron turnover and storage; (7) the "pitting function"; (8) destruction of old red cells.

Photocyclization of photoswitches with high enantioselectivity in human serum albumin in an artificial environment

2017 ◽  
Vol 53 (22) ◽  
pp. 3181-3184 ◽  
Author(s):  
Koichi Kawamura ◽  
Ken Osawa ◽  
Yuta Watanobe ◽  
Yuri Saeki ◽  
Naoki Maruyama ◽  
...  
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Uv Irradiation ◽  
Phosphate Buffer ◽  
Enantiomeric Excess ◽  
Phosphate Buffer Solution ◽  
Ring Closure ◽  
Buffer Solution ◽  
Artificial Environment

Three photochromic bisthienylethenes exhibited 56 to >99% enantiomeric excess in photochemical ring closure upon UV irradiation when incorporated in human serum albumin dissolved in 15% acetonitrile-phosphate buffer solution and incubated for 24 h at −4 °C.

The release of radioactive arachidonate from lipids of red blood cells during prolonged incubations in vitro

1987 ◽  
Vol 65 (5) ◽  
pp. 444-451 ◽  
Author(s):  
R. Roy Baker ◽  
Zou Dao Loh
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Time Course ◽  
White Blood Cells ◽  
Red Cells ◽  
Biologically Active ◽  
Red Cell

Red blood cells were isolated from rat blood and incubated in the presence of [3H]arachidonate. A sizeable quantity (18%) of the radioactivity was incorporated into red cell lipids, of which phosphatidylcholine was the most highly labelled. Radioactive arachidonate was found at position 2 of this phospholipid. Free fatty acids were removed by washing the cells in solutions containing fatty-acid-free bovine serum albumin. The labelled red cells were then incubated for up to 16 h at 37 °C. After 16 h of incubation in saline–buffer–glucose or rat serum, 20 and 26%, respectively, of the total radioactivity was found in free fatty acids, and there were corresponding declines in the percentage radioactivities found in phosphatidylcholine. In the presence of serum, there was a more rapid release of radioactive fatty acid over the 2- to 16-h time course. There was not a significant drop in the phosphate levels of the total red cell phospholipids or phosphatidylcholine after 16 h of incubation and, as a result, there were large declines in the specific radioactivities of phosphatidylcholine. Diacylglycerols were not highly labelled and the action of phospholipase A2 on labelled phosphatidylcholine was indicated. When white blood cells were added to labelled red cells, there was little evidence of white cell involvement in the release of radioactive fatty acid, suggesting that the red cells themselves may be involved in arachidonate release. Red cells may serve as sources of arachidonate, released following hemorrhage in brain and metabolized to form various biologically active eicosanoids.

Multivariate Determination of Human Serum Albumin and γ-Globulin in a Phosphate Buffer Solution by near Infrared Spectroscopy

1998 ◽  
Vol 6 (1) ◽  
pp. 375-381 ◽  
Author(s):  
Koichi Murayama ◽  
Keiichi Yamada ◽  
Roumiana Tsenkova ◽  
Yan Wang ◽  
Yukihiro Ozaki
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Standard Error ◽  
Phosphate Buffer ◽  
Near Infrared ◽  
Phosphate Buffer Solution ◽  
Clinical Analysis ◽  
Pls Regression ◽  
Buffer Solution

Near infrared (NIR) spectra in the 1300–1850 nm region were measured for phosphate buffer solutions containing both human serum albumin and γ-globulin with various concentrations. The concentrations of albumin and γ-globulin were determined by partial least squares (PLS) regression analysis. The calibration for albumin in the concentration ranges of 0.100–8.000 g dL−1 yielded the correlation coefficient ( R) of 0.998, the standard error of calibration ( SEC) of 0.124 g dL−1, and the standard error of prediction ( SEP) of 0.152 g dL−1, respectively. Those for γ-globulin in the concentration ranges of 0.100–6.000 g dL−1 yielded were 0.998, 0.110 g dL−1 and 0.118 g dL−1, respectively. The regression coefficients ( RCs) of PLS factors for albumin were compared with those for γ-globulin. The differences were discussed for each RC between albumin and γ-globulin. The coefficient of variation ( CV) was calculated to be 0.0388 and 0.0374 for albumin and γ-globulin, respectively. The ratio of standard derivation of reference data in prediction set to SEP ( RPD) are 13.4 and 16.4 for them. These values obtained in the present study satisfy the demands of clinical analysis of blood. The present results demonstrate that it is possible to determine the concentrations of the two kinds of proteins in the solution simultaneously by use of NIR and PLS regression.

Reduction of Escherichia coli O157:H7 Counts on Whole Fresh Apples by Treatment with Sanitizers

2000 ◽  
Vol 63 (6) ◽  
pp. 703-708 ◽  
Author(s):  
MARCY A. WISNIEWSKY ◽  
BONITA A. GLATZ ◽  
MARK L. GLEASON ◽  
CHERYLL A. REITMEIER
Keyword(s):  
Escherichia Coli ◽  
Chlorine Dioxide ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Escherichia Coli O157 ◽  
Peroxyacetic Acid ◽  
Water Control ◽  
Buffer Solution ◽  
E Coli ◽  
Log Reduction

The objectives of this study were to determine if washing of whole apples with solutions of three different sanitizers (peroxyacetic acid, chlorine dioxide, or a chlorine-phosphate buffer solution) could reduce a contaminating nonpathogenic Escherichia coli O157:H7 population by 5 logs and at what sanitizer concentration and wash time such a reduction could be achieved. Sanitizers were tested at 1, 2, 4, 8, and 16 times the manufacturer's recommended concentration at wash times of 5, 10, and 15 min. Whole, sound Braeburn apples were inoculated with approximately 1 × 108 or 7 × 106 CFU per apple, stored for 24 h, then washed with sterile water (control) or with sanitizers for the prescribed time. Recovered bacteria were enumerated on trypticase soy agar. Washing with water alone reduced the recoverable population by almost 2 logs from the starting population; this can be attributed to physical removal of organisms from the apple surface. No sanitizer, when used at the recommended concentration, reduced the recovered E. coli population by 5 logs under the test conditions. The most effective sanitizer, peroxyacetic acid, achieved a 5-log reduction when used at 2.1 to 14 times its recommended concentration, depending on the length of the wash time. The chlorine-phosphate buffer solution reduced the population by 5 logs when used at 3 to 15 times its recommended concentration, depending on wash time. At no concentration or wash time tested did chlorine dioxide achieve the 5-log reduction.

Investigation of the Effects of Various Cyclodextrins on the Stabilisation of Human Serum Albumin by a Spectroscopic Method

2015 ◽  
Vol 68 (12) ◽  
pp. 1894 ◽  
Author(s):  
Mohsen Oftadeh ◽  
Golamreza Rezaei Behbahani ◽  
Ali Akbar Saboury ◽  
Shahnaz Rafiei
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Electrostatic Interactions ◽  
Spectroscopic Method ◽  
Phosphate Buffer Solution ◽  
Blue Shift ◽  
Titration Calorimetry ◽  
Tryptophan Residue ◽  
Buffer Solution

The binding parameters between cyclodextrins (CDs) and human serum albumin (HSA) were investigated by isothermal titration calorimetry (ITC), fluorescence quenching, and UV-vis absorption spectroscopy at 300 K in 50 mM phosphate buffer solution. Among the various CDs investigated, β-CD has the greater ability to decrease the aggregation of HSA and the results indicated that the inhibition order is γ-CD < α-CD < β-CD. The obtained heats for HSA+CDs interactions were reported and analysed in terms of the extended solvation model, which was used to reproduce the enthalpies of HSA interactions with CDs over a broad range of complex concentrations. The binding constant and thermodynamic parameters were obtained. These suggested that the binding reaction was driven by both enthalpy and entropy, and electrostatic interactions played a major role in the stabilising of HSA. The parameters and reflected the net effect of β-CD on the HSA stability at low and high cyclodextrin concentrations, respectively. The positive values for indicated that β-CD stabilises the HSA structure at low concentrations. The UV absorption intensity of theses complexes increased and a slight red shift was observed in the absorbance wavelength with increasing the CD concentration. The fluorescence intensity of HSA decreased regularly and a slight blue shift was observed for the emission wavelength with increasing CD concentration. The results indicate that the CD complex could quench the fluorescence of HSA and changes the microenvironment of the tryptophan residue.

Electrocatalytic performance of a zinc sulphide nanoparticles-modified carbon paste electrode for the simultaneous determination of acetaminophen, guanine and adenine

2018 ◽  
Vol 10 (11) ◽  
pp. 1362-1371 ◽  
Author(s):  
Mallappa Mahanthappa ◽  
Nagaraju Kottam ◽  
Shivaraj Yellappa
Keyword(s):  
Carbon Paste Electrode ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Zinc Sulphide ◽  
Modified Carbon Paste Electrode ◽  
Carbon Paste ◽  
Buffer Solution ◽  
Guanine And Adenine ◽  
Paste Electrode

The simultaneous electroanalysis of acetaminophen (AC), guanine (G) and adenine (A) was successfully achieved on the zinc sulphide nanoparticles-modified carbon paste electrode (ZnS NPs/CPE) in phosphate buffer solution (PBS).

Microfluidic concentration enhancement of bio-analyte by temperature gradient focusing via Joule heating by DC plus AC field: A numerical approach

2021 ◽  
pp. 1-17
Author(s):  
Amitava Dutta ◽  
Apurba Kumar Santra ◽  
Ranjan Ganguly
Keyword(s):  
Temperature Gradient ◽  
Joule Heating ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Numerical Approach ◽  
High Concentration ◽  
Buffer Solution ◽  
Temperature Gradient Focusing ◽  
Ac Field ◽  
Target Analyte

Abstract We present a detailed numerical analysis of electrophoresis induced concentration of a bio-analyte facilitated by temperature gradient focusing in a phosphate buffer solution via Joule heating inside a converging-diverging microchannel. The purpose is to study the effects of frequency of AC field and channel width variation on the concentration of target analyte. We tune the buffer viscosity, conductivity and electrophoretic mobility of the analyte such that the electrophoretic velocity of the analyte locally balances the electroosmotic flow of the buffer, resulting in a local build-up of the analyte concentration in a target region. An AC field is superimposed on the applied DC field within the microchannel in such a way that the back pressure effect is minimized, resulting in minimum dispersion and high concentration of the target analyte. Axial transport of fluorescein-Na in the phosphate buffer solution is controlled by inducing temperature gradient through Joule heating. The technique leverages the fact that the buffer's ionic strength and viscosity depends on temperature, which in turn guides the analyte transport. A numerical model is proposed and a finite element-based solution of the coupled electric field, mass, momentum, energy and species equations are carried out. Simulation predict peak of 670-fold concentration of fluorescein-Na is achieved. The peak concentration is found to increase sharply as the channel throat width, while the axial spread of concentrated analyte increases at lower frequency of AC field. The results of the work may improve the design of micro concentrator.

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