1/8. Hb Mont Saint Aignan [beta128(H6)Ala-->Pro]: a new unstable variant leading to chronic microcytic anemia.Hb Mont Saint-Aignan [beta128(H6)Ala-->Pro] is a mildly unstable variant, associated with hemolytic anemia, marked microcytosis and increased alpha/beta biosynthetic ratio (1.55 versus 1.1 /- 0.1 in the control). The abnormal chain was isolated by selective precipitation with isopropanol and the structural modification determined by protein chemistry methods (reversed phase high performance liquid chromatography and mass spectrometry). Possible mechanisms underlying the beta( )-thalassemia-like expression of this variant are discussed.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
2/8. Hb Isehara (or Hb Redondo) [beta 92 (F8) HisAsn]: an unstable variant with a proximal histidine substitution at the heme contact. A 50-year-old Japanese female patient was found to have hemolytic anemia. Isoelectrofocusing of her hemolysate revealed two abnormal hemoglobin bands, one of which was very close to the Hb A2 band, and the other between the Hb A2 and Hb F bands. CM-cellulose column chromatography of the globin prepared from the abnormal hemoglobin showed that the abnormal chain eluted faster than the normal beta and delta chains; the beta X chain, however, did not separate from the normal beta chain in urea cellulose acetate electrophoresis. An instability test of the patient's hemolysate revealed the presence of an unstable component. Structural analysis of the abnormal beta chain indicated that the histidine residue at beta 92(F8) was replaced by an asparagine or aspartic acid residue. DNA amplified by polymerase chain reaction was sequenced by the dideoxy method. The nucleotide sequence of the beta 92 codon was AAC instead of CAC, suggesting that the amino acid substitution corresponded to His Asn, which is the same as is found in Hb Redondo or beta 92(F8)His Asn Asp.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
3/8. Hb Sun Prairie or alpha(2)130(H13)AlaPro beta 2, a new unstable variant occurring in low quantities. A severe hemolytic anemia with microcytosis and hypochromia was present in a young adopted Indian patient. Reversed phase high performance liquid chromatographic methodology and heat stability tests detected an unstable alpha chain which was present in 3 to 5% of the total hemoglobin. A larger quantity of the alpha X chain was obtained by preparative reversed phase high performance liquid chromatography. Structural analyses identified an Ala Pro replacement at position 130 of the alpha chain. The instability of the variant, named Hb Sun Prairie, is comparable to that of Hb Bibba [alpha 136 (H19)Leu Pro]. Gene mapping failed to detect an alpha-thalassemia deletion (alpha alpha/alpha alpha), while dot-blot analysis of amplified DNA with synthetic probes localized a G C mutation in codon 130 (resulting in the Ala Pro mutation) of the alpha 2-globin genes of both chromosomes. These results suggest a homozygosity for the G C mutation and the condition alpha 2(G C)alpha 1/alpha 2(G C)alpha 1 adequately explains the rather severe clinical status of this child, including the marked microcytosis and hypochromia. Unfortunately, family studies to exclude the presence of a large deletion involving all zeta- and alpha-globin genes were not possible.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
4/8. Hb Mizuho [beta 68(E12)LeuPro]. Second occurrence identified in a Caucasian child with hemolytic anemia and dense erythrocyte inclusions. Hb Mizuho [beta 68(E12)Leu Pro] was identified in a child of Italian/Sicilian descent who exhibited severe, transfusion dependent hemolytic anemia which improved following splenectomy. The patient's peripheral blood smear, which prior to splenectomy demonstrated coarse erythrocytic basophilic stippling, showed large, dense erythrocytic hemoglobin inclusions following splenectomy. Whole blood oxygen equilibrium results were consistent with the presence of a hemoglobin component exhibiting increased oxygen affinity with decreased cooperativity. The abnormal beta chain was characterized by high performance liquid chromatography analysis of the isopropanol precipitable hemoglobin fraction.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
5/8. A new unstable haemoglobin variant: Hb Shanghai [beta 131(H9)GlnPro] found in china. A 34-year-old woman patient was found to have a chronic hereditary haemolytic anaemia. No abnormal haemoglobin band was detected by conventional electrophoresis, but a slow beta chain could be separated on urea-carboxymethyl cellulose chromatography. Investigations of the patient's haemoglobin revealed an unstable component. Analyses of chemical structure, including isolation and TPCK trypsin digestion of the abnormal globin chain. HPL chromatography, amino acid composition as well as sequence determination of the abnormal peptide, indicated that a glutamine was replaced by a proline at position beta 131 (H9). Biosynthesis studies demonstrated a normal rate of synthesis but relatively fast degradation of the mutant beta chain. The new variant is named as Hb Shanghai according to the place where it was discovered.- - - - - - - - - - ranking = 2keywords = chromatography (Clic here for more details about this article) |
6/8. A new case of congenital dyserythropoietic anaemia, type III: studies of the cell cycle distribution and ultrastructure of erythroblasts and of nucleic acid synthesis in marrow cells.The clinical and laboratory findings in an asymptomatic 19-year-old Welshman with congenital dyserythropoietic anaemia (CDA) type III are described. The blood film showed macrocytosis and red cell fragmentation and there was biochemical evidence of intravascular haemolysis. The bone marrow showed erythroid hyperplasia, megaloblastic erythropoiesis and several giant multinucleate erythroblasts. Some mononucleate erythroblasts were large and had relative DNA contents of 4-8c and the bi- and multinucleate erythroblasts had total DNA contents of 2-16c. Some of the multinucleate erythroblasts displayed a variety of ultrastructural abnormalities, including marked differences in the appearances of the individual nuclei within the same cell. The marrow cells gave a normal deoxyuridine-suppressed value indicating that the megaloblastic changes were not caused by an impairment of the methylation of deoxyuridylate. The rates of incorporation of 14C-glycine and 14C-adenine into both the DNA and rna of bone marrow cells were within the normal range. Furthermore, the average rate of elongation of newly-synthesised, 3H-thymidine-labelled daughter DNA strands, assessed by hydroxyapatite chromatography of alkali-denatured DNA was found to be normal. The results suggest that there is no impairment of dna replication in the majority of the erythroblasts and that the abnormality of erythropoiesis resulted from disturbances during mitosis and the g2 phase.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
7/8. Two cases of phosphofructokinase deficiency associated with congenital hemolytic anemia found in japan.Two kindreds of phosphofructokinase (PFK) deficiency associated with congenital nonspherocytic hemolytic anemia and mild myopathy were found in japan. Both probands had jaundice, gallstones, and slight to moderate degree of exercise intolerance. They showed decreased level of red cell PFK activity and no increase of blood lactate in forearm ischemic exercise test. We studied these probands' red cell PFKs by partial purification and condensation. Muscle type isozyme of PFK in both cases was not demonstrable in starch gel electrophoresis and DEAE-Sephadex chromatography. The clinical symptoms are considered to be due to a defect of muscle type isozyme.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
8/8. Hb Volga [beta 27(B9)Ala-->Asp]: detection of a de novo mutation by Ava II digestion of PCR-amplified DNA.Hb Volga was observed as a de novo mutation in a 5-year-old boy from Tuzla, Bosnia and Hercegovina, who exhibited severe Heinz body hemolytic anemia. The variant was detected and quantitated at 10.6% by a reversed phase high performance liquid chromatography (HPLC) procedure. Structural characterization was done by HPLC analysis. An easier approach for the detection of Hb Volga by Ava II digestion of polymerase chain reaction-amplified DNA is described.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |