In an attempt to stimulate Hb F synthesis in baboons by means other than erythropoietic stress, we considered the possibility that an agent that inhibits methylation of CpG sequences in DNA may be effective. 5-Azacytidine, a cytosine analogue that cannot be methylated, is such an agent. Animals whose packed red cell volume was maintained at approximately 20% by bleeding were given 10 daily intr...

OBJECTIVE To assess the effect of an incremental increase in faecal haemoglobin (f-Hb) concentration on colorectal cancer (CRC) mortality and all-cause death. DESIGN We conducted an observational study of cohorts over time based on two population-based CRC screening programmes. SETTING Two cities of Taiwan. PARTICIPANTS 1233 individuals with CRC (217 prevalent cases and 1016 incident case...

We cultured human umbilical cord blood erythropoietic precursors in methyl cellulose clonal assay and analyzed the synthetic rates of Hb A and Hb F in individual erythropoietic bursts. Hemoglobin was labeled with 14C-amino acids in culture, separated by slab gel isoelectric focusing techniques, and quantitated by fluorographic methods. Almost all bursts exhibited both Hb A and Hb F in varying r...

background: molecular genetic factors regulating hemoglobin f (hb f) expression are important modifiers of the severity of sickle cell anemia (ss).   methods: the prevalence of xmni polymorphic site, the g g: a g ratio and the hb f level were determined using pcr-rflp procedure, hplc and alkaline denaturation method, respectively, in various haplotypes of 52 patients with ss, 18 patients with s...

OBJECTIVE This study aimed to document the transition of hemoglobin (Hb) F levels from early childhood to adulthood in Kuwaiti sickle cell disease patients, investigating its relationship to sex, Hb genotype and coexistence of alpha-thalassemia trait. SUBJECTS AND METHODS The following parameters were extracted from the patients' records: age, sex, Hb, mean corpuscular volume, mean corpuscula...

BACKGROUND: The thalassemic syndromes originate from mutations of the globin genes that cause, besides the characteristic clinical picture, also an increased Hb F amount. It is not yet clear if there are more factors, besides the beta globin genotype, determining the Hb F production. We have tried to find out if there are relations between total Hb and Hb F, between erythropoietin (Epo) and Hb ...

Specific antibodies to human fetal hemoglobin were prepared and, after conjugation with a fluorescent dye, were used to determine the distribution of Hb F-containing cells in blood smears from normal adults and individuals with hereditary and acquired conditions associated with abnormal levels of Hb F. The mean proportion of F-cells in normal persons was 2.7% +/- 1.4%, with a range of 0.5%-7.0%...

The in vitro effect of S-stage-specific drugs on the fetal hemoglobin (Hb F) potential of erythroid precursors and progenitors was tested by exposing bone marrow cells to 5-aza-2'-deoxycytidine, Ara-C, or hydroxyurea in suspension cultures and reculturing the cells in drug-free clonal cultures. Analysis of Hb F in the erythroblasts present at the end of suspension cultures and in the erythroid ...

We investigated whether mutations in the KLF1 gene are associated with increased Hb F levels in ethnically diverse patients referred to our laboratory for hemoglobinopathy investigation. Functionally effective KLF1 mutations were identified in 11 out of 131 adult samples with an elevated Hb F level (1.5-25.0%). Eleven different mutations were identified, 9 of which were previously unreported. K...

Hb Hoshida (␤43Glu3 Gln). All 4 patients with abnormal peaks at the S window on HPLC (mean retention time, 0.91 min) had Hb Queens (␣1 34Leu3 Arg). All 10 patients with variant peaks were heterozygous, and they had abnormal bands within the Hb S/Hb G/Hb D area on cellulose acetate Hb electrophoresis. Hb G Coushatta has been found in Koreans, Chinese, and in some Japa-nese families (6). This var...