NONSPHEROCYTIC CONGENITAL HEMOLYTIC ANEMIA DUE TO A NEW G-6-PD VARIANT: G-6-PD ALHAMBRA

An 11-year-old boy was first known to have a hemolytic episode at the age of 8 years, and a diagnosis of nonspherocytic congenital hemolytic anemia due to G-6-PD deficiency was made soon after the hemolytic episode. The red cells of the patient contained a level of G-6-PD activity approximating 10 to 25% of normal. The residual enzyme was partly purified and characterized. It proved to be electrophoretically slow, and was kinetically essentially normal. The thermal stability of the enzyme was reduced and its stability in vivo was markedly diminished. This enzyme represents a new variant which has been named G-6-PD Alhambra.

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Congenital Hemolytic Anemia with High Sodium, Low Potassium Red Cells

New England Journal of Medicine ◽

10.1056/nejm196803142781101 ◽

1968 ◽

Vol 278 (11) ◽

pp. 573-581 ◽

Cited By ~ 83

Author(s):

Harold S. Zarkowsky ◽

Frank A. Oski ◽

Ramadan Sha'afi ◽

Stephen B. Shohet ◽

David G. Nathan

Keyword(s):

Hemolytic Anemia ◽

Red Cells ◽

High Sodium ◽

Low Potassium ◽

Congenital Hemolytic Anemia

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Temperature-dependent adjustment of the thermal stability of photosystem II in vivo: possible involvement of xanthophyll-cycle pigments

Planta ◽

10.1007/bf00620047 ◽

1996 ◽

Vol 198 (3) ◽

pp. 324-333 ◽

Cited By ~ 125

Author(s):

Michel Havaux ◽

Florence Tardy

Keyword(s):

Thermal Stability ◽

Photosystem Ii ◽

Xanthophyll Cycle ◽

Temperature Dependent ◽

Xanthophyll Cycle Pigments ◽

Thermal Stability Of

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Effects of glycine betaine and glycerophosphocholine on thermal stability of ribonuclease

AJP Renal Physiology ◽

10.1152/ajprenal.1998.274.4.f762 ◽

1998 ◽

Vol 274 (4) ◽

pp. F762-F765 ◽

Cited By ~ 6

Author(s):

Maurice B. Burg ◽

Eugenia M. Peters

Keyword(s):

Thermal Stability ◽

Tissue Culture ◽

Glycine Betaine ◽

Metabolic Cost ◽

Rnase A ◽

Renal Cells ◽

And Function ◽

Thermal Stability Of

Urea in renal medullas is sufficiently high to perturb macromolecules, yet the cells survive and function. The counteracting osmolytes hypothesis holds that methylamines, such as glycine betaine (betaine) and glycerophosphocholine (GPC) in renal medullas, stabilize macromolecules and oppose the effects of urea. Although betaine counteracts effects of urea on macromolecules in vitro and protects renal cells from urea in tissue culture, renal cells accumulate GPC rather than betaine in response to high urea both in vivo and in tissue culture. A proposed explanation is that GPC counteracts urea more effectively than betaine. However, we previously found GPC slightly less effective than betaine in counteracting inhibition of pyruvate kinase activity by urea. To test another macromolecule, we now compare GPC and betaine in counteracting reduction of the thermal stability of RNase A by urea. We find that urea decreases the thermal transition temperature and that betaine and GPC increase it, counteracting urea approximately equally. Therefore, the preference for GPC in response to high urea presumably has some other basis, such as a lower metabolic cost of GPC accumulation.

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A comparative analysis of the evolutionary patterning and mechanistic bases of lactate dehydrogenase thermal stability in porcelain crabs, genus Petrolisthes

Journal of Experimental Biology ◽

10.1242/jeb.204.4.767 ◽

2001 ◽

Vol 204 (4) ◽

pp. 767-776

Author(s):

J.H. Stillman ◽

G.N. Somero

Keyword(s):

Thermal Stability ◽

Comparative Analysis ◽

Lactate Dehydrogenase ◽

Protein Interactions ◽

Kinetic Properties ◽

Post Translational Modification ◽

Extrinsic Factors ◽

Thermal Stability Of ◽

Interspecific Diversity

The kinetic properties of orthologous homologs (orthologs) of enzymes are typically correlated with environmental temperatures in species adapted to different thermal regimes, but correlations between adaptation temperature and enzyme thermal stability are less clear. Although the thermal stability of a protein is related chiefly to its primary structure (including post-translational modification), thermal stability can also be altered by extrinsic factors present in the intracellular milieu. Here, we present a comparative analysis of the thermal stability of lactate dehydrogenase (LDH) orthologs from 22 congeneric species of porcelain crab (genera Petrolisthes and Allopetrolisthes) from a broad range of thermal habitats. Interspecific diversity of LDH stability is high: temperatures required for a 50 % loss of activity in 10 min ranged from 65 to 75.5 degrees C, corresponding to half-lives of less than 1 min to more than 3 h at 70 degrees C. Although stability is positively correlated with maximal habitat temperature in some sister taxa, phylogenetic comparative analysis incorporating all 22 species does not indicate that the interspecific diversity of LDH stability represents an adaptive response to current thermal habitats. Examination of the mechanistic bases of LDH stabilization indicates that differences in stability are related both to properties of the LDH molecule itself (intrinsic stability) and to the effects of extrinsic protein(s). Intrinsic differences were shown by the unfolding of structure during heating, as measured by circular dichroism spectroscopy. Stabilizing effects of extrinsic proteins are implied by the results of cellular fractionation experiments that removed low-molecular-mass solutes and proteins from the muscle homogenates. We conclude that the overall structural stability and functional properties of proteins can evolve independently and that in vivo protein-protein interactions can provide another means to regulate protein stability selectively.

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Reduction of Prion Infectivity in Packed Red Cells by Separation of Whole Blood and Washing of the Red Cell Fraction.

Blood ◽

10.1182/blood.v110.11.2890.2890 ◽

2007 ◽

Vol 110 (11) ◽

pp. 2890-2890

Author(s):

Rodrigo Morales ◽

Kimberley A. Buytaert-Hoefen ◽

Eric T. Hansen ◽

Dennis Hlavinka ◽

Raymond Goodrich ◽

...

Keyword(s):

Blood Cell ◽

Red Blood Cell ◽

Whole Blood ◽

Red Cells ◽

Cell Fraction ◽

Health Concern ◽

Red Cell ◽

New Variant

Abstract Although prion diseases are rare in humans, the established link between a new variant form of CJD (vCJD) and the consumption of cattle meat contaminated by BSE have raised concerns about a possible outbreak of a large epidemic in the human population. Over the past few years, BSE has become a significant health concern in several countries, and it now seems apparent that vCJD can also be iatrogenically transmitted from human to human by blood transfusion. Exacerbating this state of affairs is the lack of a reliable test to identify individuals incubating the disease during the long and silent period from the onset of infection to the appearance of clinical symptoms. The purpose of this research study was to evaluate the effectiveness of separation of whole blood and washing of the red cell fraction for the removal of infectious scrapie prion protein (PrPSc) from red blood cell (RBC) suspensions. Samples of human, whole blood were spiked with 5 × 106 LD50 263K PrPSc. Analysis of the treated sample supernatants by Western blot revealed that approximately >88% of the PrPSc was removed with the initial plasma expression and the equivalent of 6% was detected in a saline wash (300 mL; 0.9% saline). The final sample of RBCs revealed no detectable levels of PrPSc by Western blots. Further analysis of the treated RBCs using the PMCA assay indicated detectable amounts of PrPSc only after 2 consecutive amplification rounds. Semi-quantitative analysis of PMCA amplification enabled us to estimate that the treated RBCs contained less than 1 × 104 LD50 PrPSc. This corresponded to removal levels exceeding ≥99% of spiked material in whole blood. These in vitro estimations were confirmed by in vivo infectivity studies in a hamster model of disease transmission. Results from in vivo studies displayed significant differences in the incubation periods of the spiked blood inoculated hamsters (100.1 ± 1.7) versus washed RBCs (135.8 ± 6.7). Moreover, a substantial difference in the attack rate (6/15: 40% in washed RBC, versus 13/13: 100% in spiked blood) further indicated a substantial removal of infectious prions. Comparison of this data with results of animals inoculated with different dilutions of infectious material, indicated a >99.94% reduction of infectivity. Washed, packed human red cells produced by this procedure were able to be stored in standard additive solutions (AS-3) for 42 days while still meeting all in vitro blood bank standards for acceptable red cell quality. Conclusion This data suggests that separation of plasma coupled with a simple, low volume wash of red cells may represent an efficient method to remove prions from red blood cell fractions, thus reducing possible infectivity of these products.

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The Effects of Concentrated Eluted Anti-Red Blood Cell Antibodies on the in Vivo Survival of Normal Red Blood Cells

Blood ◽

10.1182/blood.v15.4.525.525 ◽

1960 ◽

Vol 15 (4) ◽

pp. 525-533 ◽

Cited By ~ 2

Author(s):

NEIL W. CULP ◽

HUGH CHAPLIN

Keyword(s):

Blood Cell ◽

Red Blood Cells ◽

Hemolytic Anemia ◽

Normal Control ◽

Red Blood Cell ◽

Blood Cells ◽

Red Cells ◽

Significant Alteration ◽

Red Cell

Abstract 1. A method has been described for the preparation and sterilization of a concentrated eluate from human red cell stroma. 2. Red cells sensitized by such an eluate prepared from normal control red cells showed entirely normal in vivo survival, as did cells sensitized by eluate from anti-H coated cells. 3. Sensitization of red cells by concentrated eluates from a patient with Coombs-negative acquired hemolytic anemia and from a patient with Coombs-positive acquired hemolytic anemia did not cause significant alteration in the in vivo survival of the red cells. 4. Red cells sensitized by the concentrated eluate from anti-D sensitized cells disappeared from the recipient’s circulation very rapidly and were sequestered in the spleen, indicating preservation of the physiologic properties of the antibody throughout the elution, concentration and sterilization procedures.

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G6PD San Francisco: a new variant of glucose-6-phosphate dehydrogenase associated with congenital nonspherocytic hemolytic anemia

Blood ◽

10.1182/blood.v55.2.195.195 ◽

1980 ◽

Vol 55 (2) ◽

pp. 195-198 ◽

Cited By ~ 2

Author(s):

WC Jr Mentzer ◽

R Warner ◽

J Addiego ◽

B Smith ◽

T Walter

Keyword(s):

San Francisco ◽

Hemolytic Anemia ◽

Cell Function ◽

Red Cells ◽

G6pd Activity ◽

Ph Optimum ◽

Bacterial Killing ◽

Virtual Absence ◽

New Variant ◽

Variant Enzyme

Abstract Congenital nonspherocytic hemolytic anemia in an adult male of Scandinavian ancestry was associated with virtual absence of G6PD activity in red cells. Characterization of G6PD purified from leukocytes using standard WHO techniques revealed diminished electrophoretic mobility, marked lability on heating at 46 degrees C, normal pH optimum and utilization of alternate substrates (2-deoxy G6P, D-amino NADP), elevated Km NADP, and striking susceptibility to NADPH inhibition. The variant G6PD, which appears to be unique, has been designated G6PD San Francisco. An unusual feature of the variant enzyme, susceptibility to inactivation by brief periods of dialysis, could be prevented by addition of 200 microM NADP to the dialysis solution. In red cells, where G6PD activity was essentially absent, regeneration of reduced glutathione was totally curtailed in vitro, while in leukocytes, where residual G6PD activity was approximately 60% of normal, hexose monophosphate shunt activity, oxygen consumption during phagocytosis, and bacterial killing were unimpaired. Thus, instability of the variant enzyme rather than its unfavorable kinetics appeared to be an important determinant of abnormal cell function.

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Red cell calcium leak in congenital hemolytic anemia with extreme microcytosis

Blood ◽

10.1182/blood.v47.2.197.197 ◽

1976 ◽

Vol 47 (2) ◽

pp. 197-210 ◽

Cited By ~ 20

Author(s):

JS Wiley ◽

FM Gill

Keyword(s):

Hemolytic Anemia ◽

Cell Morphology ◽

Osmotic Fragility ◽

Red Cells ◽

Red Cell ◽

Fresh Blood ◽

Ouabain Binding ◽

Red Cell Membrane ◽

Membrane Area ◽

Congenital Hemolytic Anemia

Abstract A child with congenital hemolytic anemia, extreme microcytosis and bizarre red cell morphology has been studied. Splenectomy at the age of 21 mo greatly improved the hemolytic anemia, although red cell morphology was unchanged. Aniso- and poikilocytosis were marked on a stained smear, and there were many small hyperchromatic cells of irregular shape. The MCV of 25 cu mu was very low and the MCHC was normal. Osmotic fragility of fresh blood was increased, and postsplenectomy blood showed a fraction of extremely fragile cells. Concentration and fluxes of Na+ and K+ were normal, except K+ efflux, which was stimulated by external Ca2+. Inward Ca2+ movement into the patient's red cells was elevated three- to fourfold above red cells of the same mean age. Red cell Ca2+ concentration was raised 2.5 times normal and most of the Ca2+ was localized in the stroma. Red cell lipid, sialic acid, and ouabain-binding sites, all per milliliter of cells, were increased by 16%-23%, and, since these substances estimate the amount of membrane, it was likely that Ca2+ content per unit of membrane area was at least twice normal. Deformability of the cells, as judged by their filterability was markedly impaired. It was concluded that the red cell membrane was defective, and an increased membrane Ca2+ content was associated with reduced deformability, hemolysis, and distorted red cell morphology in this syndrome.

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