Hematologic disorders of children in developing countries

Bacteria-assisted biogreen synthesis of radical scavenging exopolysaccharide-iron complexes: an oral nano-sized nutritional supplement with high in vivo compatibility

Microbial exopolysaccharides (EPSs) have recently served as an efficient substrate for the production of biocompatible metal nanoparticles (NPs) given their favorable stabilizing and reducing properties due to the presence of polyanionic functional groups in their structure. In the present work, Pantoea sp. BCCS 001 GH was used to produce EPS-stabilized biogenic Fe NPs as a complex through a novel biosynthesis reaction. Physicochemical characterization of the EPS-Fe complex was performed, indicating high thermal stability, desirable magnetic properties due to the uniform distribution of the Fe NPs with the average size of ∼10 nm and spherical shape within the EPS matrix. In addition, the in vivo toxicity of the EPS-stabilized Fe NPs was evaluated to investigate their potential for the treatment of iron deficiency anemia. Biological blood parameters and organ histology studies confirmed very high safety of the biosynthesized composite, making EPS-Fe a suitable candidate with an economical and environment friendly synthesis method for a wide spectrum of potential fields in medicine.

The Effects of Nanoparticles Containing Iron on Blood and Inflammatory Markers in Comparison to Ferrous Sulfate in Anemic Rats

Background:

Ferrous sulfate is the most used supplement for treating anemia, but it can result in unfavorable side effects. Nowadays, nanotechnology is used as a way to increase bioavailability and decrease the side effects of drugs and nutrients. This study investigates the effects of nanoparticles containing iron on blood and inflammatory markers in comparison to ferrous sulfate in anemic rats.

Methods:

To induce the model of hemolytic anemia, 50 mg/kg bw phenylhydrazine was injected intraperitoneally in rats on the 1^st day and 25 mg/kg bw for the four following days. Then, rats were randomly divided into five groups. No material was added to the nipple of the Group 1 (control). Group 2 received 0.4 mg/day nanoparticles of iron; Group 3 received 0.4 mg/day ferrous sulfate, and Groups 4 and 5 received double dose of iron nanoparticle and ferrous sulfate, respectively for ten days.

Results:

Hemoglobin and red blood cell (RBC) in Group 2 were significantly higher than Group 3 (P < 0.05). In addition, hemoglobin and RBC in Group 4 and 5 were significantly higher than Group 3 (P < 0.05). The average level of serum iron in Groups 2 and 4 was remarkably more than the groups received ferrous sulfate with similar doses (P < 0.05). C-reactive protein in Group 3 was more than Group 2 and in Group 5 was more compare to all other groups.

Conclusions:

Single dose of nanoparticles had more bioavailability compare to ferrous sulfate, but this did not occur for the double dose. Furthermore, both doses of nanoparticles caused lower inflammation than ferrous sulfate.

Reappraisal of known malaria resistance loci in a large multicenter study

Many human genetic associations with resistance to malaria have been reported, but few have been reliably replicated. We collected data on 11,890 cases of severe malaria due to Plasmodium falciparum and 17,441 controls from 12 locations in Africa, Asia and Oceania. We tested 55 SNPs in 27 loci previously reported to associate with severe malaria. There was evidence of association at P < 1 × 10(-4) with the HBB, ABO, ATP2B4, G6PD and CD40LG loci, but previously reported associations at 22 other loci did not replicate in the multicenter analysis. The large sample size made it possible to identify authentic genetic effects that are heterogeneous across populations or phenotypes, with a striking example being the main African form of G6PD deficiency, which reduced the risk of cerebral malaria but increased the risk of severe malarial anemia. The finding that G6PD deficiency has opposing effects on different fatal complications of P. falciparum infection indicates that the evolutionary origins of this common human genetic disorder are more complex than previously supposed.

Acute haemolytic crisis in a Thai patient with homozygous haemoglobin Constant Spring (Hb CS/CS): a case report

Acute haemolysis associated with mild upper respiratory tract infection was observed in a Thai boy who presented with a rapid decline in haemoglobin (Hb) levels, haemoglobinuria and evidence of intravascular haemolysis. Several possible causes giving rise to such a condition were excluded including G6PD deficiency, which is extremely common in Thailand. Subsequent haematological and molecular analyses demonstrated that the patient was homozygous for Hb Constant Spring (Hb CS/CS), an a globin haemoglobinopathy. It has been shown previously that patients with homozygous Hb CS had mild haemolytic anaemia secondary to an accumulation of alpha(CS) chains, which are toxic to red blood cell membrane cytoskeletons. Increased body temperature might induce more precipitation of this a globin variant. This report highlights the importance of Hb CS/CS as a potential predisposing cause of acute haemolysis in children that might be aggravated by acute bacterial or viral infections. This is particularly relevant for patients of Southeast Asian descent where this abnormal haemoglobin is highly prevalent.

HbE/β-thalassemia: basis of marked clinical diversity

Hemoglobin E thalassemia accounts for about one-half of all cases of severe beta thalassemia. There is marked variability in its clinical severity ranging from an asymptomatic to a transfusion-dependent phenotype. The phenotypic variability and inadequate longitudinal data present challenges in determining the optimal management of patients. This article summarizes findings on the natural history of Hemoglobin E thalassemia and some factors responsible for its clinical heterogeneity. Major genetic factors include the type of beta thalassemia mutation, the co-inheritance of alpha thalassemia, and polymorphisms associated with increased synthesis of fetal hemoglobin. Other factors, including response to anemia, and the influence of infection with malaria and other environmental influences, may be important. The remarkable variation and instability of clinical phenotypes in Hemoglobin E thalassemia require individual management plans for each patient, which should be reassessed over time.

Studies in haemoglobin E beta-thalassaemia

Haemoglobin E beta-thalassaemia is the commonest form of severe thalassaemia in many Asian countries, but little is known about its natural history, the reasons for its clinical diversity, or its optimal management. Despite its frequency, haemoglobin E beta-thalassaemia is often managed in an ill-defined and haphazard way, usually by demand transfusion. We studied a cohort of Sri Lankan patients with haemoglobin E beta-thalassaemia over 5 years, and identified several genetic and environmental factors possibly contributing to the phenotypic diversity of the disorder. These included modifiers of haemoglobin F production, malaria and age-related changes in adaptation to anaemia. Our findings suggest that in many patients, haemoglobin E beta-thalassaemia can be managed without transfusion, even with low haemoglobin levels. Age-related changes in the pattern of adaptation to anaemia suggest that more cost-effective approaches to management should be explored.