Cysteine proteinases expressed by schistosomes appear to play key roles in the digestion of host hemoglobin, the principal source of amino acid nutrients utilized by these parasites. We have shown previously that the predominant cysteine proteinase activity in soluble extracts and excretory/secretory (ES) products of adults of Schistosoma mansoni and S. japonicum is cathepsin L-like in its subs...

A human leukemic cell line KU 812 was recently established and described as a basophilic cell line. In the present study we show that KU 812 and two of its clones are at least bipotent: in addition to a minor component of basophils, the majority of KU 812 cells belongs to the erythroid cell lineage with a significant percentage (about 15%) of mature hemoglobinized erythroblasts. This terminal d...

Persistent expression of the gamma-globin genes in adults with deletion types of hereditary persistence of fetal hemoglobin (HPFH) is thought to be mediated by enhancer-like effects of DNA sequences at the 3' breakpoints of the deletions. A transgenic mouse model of deletion-type HPFH was generated by using a DNA fragment containing both human gamma-globin genes and HPFH-2 breakpoint DNA sequen...

BACKGROUND Caste is one of the traditional measures of social segregation in India and differs from other indicators as it is both, endogamous and hereditary. Evidence suggests that belonging to lower castes exposes one to social inequalities and affects health adversely. We examined the association of caste with childhood anemia in India and explored the effect modifying role of adult educatio...

Natural deletions of the human β-globin gene cluster lead to specific syndromes characterized by increased production of fetal hemoglobin in adult life and provide a useful model to delineate novel cis-acting elements involved in the developmental control of hemoglobin switching. A hypothesis accounting for these phenotypic features, assumes that silencers located within the Aγ to δ-gene region...

The acknowledged success of the Monod-Wyman-Changeux (MWC) allosteric model stems from its efficacy in accounting for the functional behavior of many complex proteins starting with hemoglobin (the paradigmatic case) and extending to channels and receptors. The kinetic aspects of the allosteric model, however, have been often neglected, with the exception of hemoglobin and a few other proteins w...

Hypoxic exposure experienced during sensitive developmental periods can shape adult physiological capabilities and define regulatory limits. Tadpole shrimp were reared under normoxic (19-21 kPa O(2)), moderate (10-13 kPa O(2)) or severe (1-3 kPa O(2)) hypoxic conditions to investigate the influence of developmental oxygen partial pressure (P(O(2))) on adult metabolic, respiratory and cardiovasc...

Homozygous sickle cell disease in the eastern province of Saudi Arabia is clinically mild. Circulating fetal hemoglobin levels of 16.0 +/- 7.4% were found in these anemic patients, but only 1.09 +/- 0.97% in their sickle trait parents. To determine whether these sickle cell anemia patients inherit an increased capacity to synthesize fetal hemoglobin, a radioimmunoassay of fetal and adult hemogl...

The in uitm biosynthesis of acetylated human fetal hemoglobin (Hb FI) was investigated in umbilical cord blood from two normal newborns and in peripheral blood from five adults with different hematologic disorders accompanied by elevated levels of fetal hemoglobin. Hemoglobin biosynthesis was measured by [8HJleucine incorporation into hemoglobin components which were separated by chromatograph...

Background: Sickle cell disease is an autosomal recessive characterized by aberrant production of hemoglobin S (HbS). The disease's presentation and severity varied substantially between people from various socioeconomic backgrounds geographical regions. clinical picture includes hemolytic anemia, vascular occlusion events, acute persistent pain, organ damage. Objective: To investigate the hema...