Polymorphisms and the Incidence of Toxicities in Children with Acute Lymphoblastic Leukemia.

Background: 6-Mercaptopurine (6-MP), a thiopurine agent, is a essential medication for treating pediatric acute lymphoblastic leukemia (ALL). However, its side effects of neutropenia and hepatotoxicity might interrupt treatment, resulting in poor outcomes. Inosine triphosphate pyrophosphatase (), an enzyme in the thiopurine pathway, may prevent the accumulation of toxic thiopurine metabolites.

Mutations in Kruppel-like factor 1 cause transfusion-dependent hemolytic anemia and persistence of embryonic globin gene expression.

In this study, we report on 8 compound heterozygotes for mutations in the key erythroid transcription factor Krüppel-like factor 1 in patients who presented with severe, transfusion-dependent hemolytic anemia. In most cases, the red cells were hypochromic and microcytic, consistent with abnormalities in hemoglobin synthesis. In addition, in many cases, the red cells resembled those seen in patients with membrane defects or enzymopathies, known as chronic nonspherocytic hemolytic anemia (CNSHA).

Clinical presentation and molecular identification of four uncommon alpha globin variants in Thailand. Initiation codon mutation of α2-globin Gene (HBA2:c.1delA), donor splice site mutation of α1-globin gene (IVSI-1, HBA1:c.95 + 1G>A), hemoglobin Queens Park/Chao Pra Ya (HBA1:c.98T>A) and hemoglobin Westmead (HBA2:c.369C>G).

Alpha thalassemia is the most common genetic disease in the world with the prevalence of carriers ranging from 5-50% in several populations. Coinheritance of two defective α-globin genes usually gives rise to a symptomatic condition, hemoglobin (Hb) H disease. Previously, it has been suggested from several studies in different populations that nondeletional Hb H disease (--/α(T)α or --/αα(T)) is generally more severe than the deletional type (--/-α).

Association of xmn I polymorphism and hemoglobin e haplotypes on postnatal gamma globin gene expression in homozygous hemoglobin e.

Background and Objectives. To explore the role of cis-regulatory sequences within the β globin gene cluster at chromosome 11 on human γ globin gene expression related to Hb E allele, we analyze baseline hematological data and Hb F values together with β globin haplotypes in homozygous Hb E. Patients and Methods.

Rapid flow cytometric test using eosin-5-maleimide for diagnosis of red blood cell membrane disorders.

Conventional diagnosis of hereditary red blood cell (RBC) membrane disorders, in particular hereditary spherocytosis (HS), is labor intensive, time consuming and requires at least 2 ml of blood, which might be impractical in neonatal period. We evaluated the use of eosin-5-maleimide (EMA), a dye that reacts covalently with lysine-430 on the first extracellular loop of band 3 protein, for rapid screening test of patients with HS and Southeast Asian Ovalocytosis (SAO). Fresh RBCs from 142 healthy controls, 50 HS, 17 SAO, 29 hereditary elliptocytosis, 5 autoimmune hemolytic anemia, 66 patients with beta-thalassemia/HbE, 31 cases with alpha-thalassemia (HbH disease) and 4 cases with pyruvate kinase deficiency were stained with EMA, and analyzed for their mean channel fluorescence (MCF) using a flow cytometer.

Development of a comprehensive red blood cell enzymopathy laboratory in Thailand: the study of normal activity in eight erythroenzymes in Thais.

In order to provide a reference range for normal red blood cell enzyme activities in Thai, we analyzed data from 113 healthy non-anemic Thai people (55 males and 58 females) age 1-42 years, who all had a normal pattern of hemoglobin typing (HbA and HbA2 less than 3.5%). Hematological analysis was performed using an automated cell counter and the hemoglobin studies were carried out by low pressure liquid chromatography.

Clinical and hematological phenotype of homozygous hemoglobin E: revisit of a benign condition with hidden reproductive risk.

Hemoglobin E (HbE) is one of the most prevalent beta-globin variant, which is widely distributed in Southeast Asia especially in Thailand. Homozygosity for this variant is common and may occur with iron deficiency. In order to study clinical and hematological phenotypes without the confounding effect of iron deficiency, investigations were carried out before and after iron supplementation for 2 months.

Flow cytometric quantitation of opsonophagocytosis and intracellular killing of Candida albicans using a whole blood microassay.

Flow cytometric assays for quantifying polymorphonuclear leucocyte (PMN) function involve peripheral blood fractionation methods. However, most are of limited use for conditions like pediatrics and thalassemia, as they may require large blood volumes or complicated by red blood cell contamination. In whole blood assay, 500-mul aliquots of normal or thalassemic whole blood were incubated with bis-carboxyethyl-carboxyfluorescein pentaacetoxymethylester (BCECF-AM)-labeled Candida albicans cells and phycoerythrin-conjugated anti-CD13 monoclonal antibody for PMNs.

Prevalence of HFE mutations among the Thai population and correlation with iron loading in haemoglobin E disorder.

Co-inheritance of HFE mutations has a substantial role in iron overload in beta-thalassaemia carriers in north European populations where two HFE mutations, C282Y and H63D, are prevalent. In Thailand, there was little information about the allele frequency of HFE mutations. It is of interest to determine whether such determinants represent a potential risk in developing iron overload as nearly 40% of the Thai population carry either one of thalassaemia or haemoglobinpathy alleles.

Allele related mutation specific-polymerase chain reaction for rapid diagnosis of Hb New York (beta 113 (G15) Val-->Glu, beta(CD113 GTG-->GAG)).

Hemoglobin New York (beta 113 (G15) Val-->Glu), a beta-globin variant, was first reported in a Chinese family living in New York. Subsequently, this abnormal hemoglobin was reported in many Chinese descendants from several groups and it was also known as Hb Kaohsiung. The subtle change in alpha1beta1 contact region apart from the heme group connecting area by Val-->Glu substitution has minor changes in both the electrophoretic mobility and stability making this hemoglobin variant difficult to distinguish from Hb A using routine hemoglobin analysis.

Effect of red blood cell glucose-6-phosphate dehydrogenase deficiency on patients with dengue hemorrhagic fever.

Eighty nine males aged 1-13 years diagnosed with dengue haemorrhagic fever (DHF) and admitted to the Department of Pediatrics Siriraj Hospital from March 1998 to April 2000 were included in this study. 17 cases (19.1%) had red blood cell glucose-6-phosphate dehydrogenase (G-6-PD) deficiency and 72 cases (80.