Acceleration of hemoglobin C crystallization by hemoglobin S

Blood ◽  
1989 ◽  
Vol 74 (5) ◽  
pp. 1823-1825
Author(s):  
MJ Lin ◽  
RL Nagel ◽  
RE Hirsch

We previously reported that circulating hemoglobin (Hb) CC erythrocytes contain oxygenated HbC crystals with little or no HbF and that HbF inhibits in vitro crystallization of HbC. We now report that HbS accelerates in vitro crystallization of HbC. Crystals were formed in 1.8 mol/L potassium phosphate buffer, pH 7.4, at 30 degrees C and were counted in several time intervals with a hematocytometer. The hemoglobin composition of Millipore-isolated crystals and supernatant were also analyzed. Under the conditions selected, 100% HbS formed needle-shaped crystals only after two hours. Pure HbC does not form crystals within 15 minutes, whereas a ratio of 10% HbS:90% HbC forms 1,100 crystals/mm3, 20% HbS:80% HbC forms 370 crystals/mm3, and 30% HbS:70% HbC forms 5 crystals/mm3. Crystals formed in the presence of HbS are tetragonal, as are pure HbC crystals. As compared with 100% HbC, HbA or albumin mixed with HbC showed a decreased number of crystals as a result of dilution. Analysis of the Hb content of isolated crystals by citrate agar gel electrophoresis showed that HbS was rapidly incorporated into the crystal in the same ratio over time. These results demonstrate that HbS accelerates crystallization of HbC with respect to the rates of crystallization of any of these two Hbs separately, through a mechanism that involves cocrystallization. These results may be significant in understanding SC disease.

Blood ◽  
1989 ◽  
Vol 74 (5) ◽  
pp. 1823-1825 ◽  
Author(s):  
MJ Lin ◽  
RL Nagel ◽  
RE Hirsch

Abstract We previously reported that circulating hemoglobin (Hb) CC erythrocytes contain oxygenated HbC crystals with little or no HbF and that HbF inhibits in vitro crystallization of HbC. We now report that HbS accelerates in vitro crystallization of HbC. Crystals were formed in 1.8 mol/L potassium phosphate buffer, pH 7.4, at 30 degrees C and were counted in several time intervals with a hematocytometer. The hemoglobin composition of Millipore-isolated crystals and supernatant were also analyzed. Under the conditions selected, 100% HbS formed needle-shaped crystals only after two hours. Pure HbC does not form crystals within 15 minutes, whereas a ratio of 10% HbS:90% HbC forms 1,100 crystals/mm3, 20% HbS:80% HbC forms 370 crystals/mm3, and 30% HbS:70% HbC forms 5 crystals/mm3. Crystals formed in the presence of HbS are tetragonal, as are pure HbC crystals. As compared with 100% HbC, HbA or albumin mixed with HbC showed a decreased number of crystals as a result of dilution. Analysis of the Hb content of isolated crystals by citrate agar gel electrophoresis showed that HbS was rapidly incorporated into the crystal in the same ratio over time. These results demonstrate that HbS accelerates crystallization of HbC with respect to the rates of crystallization of any of these two Hbs separately, through a mechanism that involves cocrystallization. These results may be significant in understanding SC disease.


1991 ◽  
Vol 5 (1) ◽  
pp. 82-86 ◽  
Author(s):  
Donald J. Daigle ◽  
Peter J. Cotty

The influences of pH, surfactants, and nutrients on germination were investigated to develop a basis for improvement ofAlternaria cassiaemycoherbicide formulations. In vitro results indicated that a formulation with a pH of approximately 6.5 containing 0.1 to 1% Tween 80, 0.02 M potassium phosphate buffer, and 1% dehydrated potato dextrose broth best promoted germination. Sicklepod plants at the 2 to 3 true-leaf stage were sprayed with test solutions, incubated in the dark at 100% relative humidity (28 C) for 6 h, and placed in a growth chamber maintained at 30 C. Assessment of the plants after 2 d indicated that the ability of the formulation components to induce germination ofAlternaria cassiaein vitro corresponded well with their ability to improve infection of sicklepod seedlings.


1977 ◽  
Vol 23 (12) ◽  
pp. 2302-2305 ◽  
Author(s):  
T J Muckle ◽  
J A Edwards ◽  
P Auckland

Abstract Lipoprotein-X is no longer detectable in serum by either the agar gel-electrophoresis/polyanion precipitation technique or immunoelectrophoresis with specific antiserum after in vitro addition of oleic acid. Evidence is presented which indicates that this ostensible loss is due not to its destruction, but rather to altered electrophoretic mobility. The findings suggest an explanation for the well known post-heparin "disappearance" of lipoprotein-X, and indicate that caution may be needed in the interpretation of such lipoprotein-X testing of sera from subjects with increased concentrations of lysolipids in their blood.


2016 ◽  
Vol 2 (1) ◽  
pp. 557-560 ◽  
Author(s):  
Steffen Lüers ◽  
Markus Laub ◽  
Herbert P. Jennissen

AbstractUltrahydrophilic titanium miniplates with sandblasted and acid etched (SLA) surfaces were protected from loss of hydrophilicity by an exsiccation layer of salt and stored in a dry state. Various salts in different concentrations were tested in respect to their conservation capacity and optical appearance. Potassium phosphate buffer in a specified composition appeared to be optimal. This optimal system was applied in a long time storage experiment showing no loss of hydrophilicity over years. It was also transferred with success to hyperhydrophilic dental implants.


The Lancet ◽  
1974 ◽  
Vol 304 (7892) ◽  
pp. 1321-1322
Author(s):  
W.H. Taylor ◽  
D.J. Etherington

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