Top PDF Characterization of molecular hemoglobin c and beta thalassemia

Characterization of molecular hemoglobin c and beta thalassemia

Characterization of molecular hemoglobin c and beta thalassemia

The World Health Organization recommends the implementation of programs for prevention and control hemoglobinopathies in Latin America, especially in Brazil (Thomas C and Lothar T, 2002). The organization of a prevention program requires support of official health agencies, skilled personnel training for diagnosis, genetic counselling and clinical patients (Orlando GM, 2000). The success of these programs depends on the responsiveness, availability and interest of the population being studied (Zamaro et al., 2002). The detection of individuals with the imperceptible forms of hemoglobinopathies, heterozygotes, are extremely important for public health because, in addition to representing a source of new heterozygotes, can, through marriages between carriers, give homozygous and double heterozygous individuals, for example, SC of hemoglobin (Hb SC), which manifest a clinical form (Orlando GM, 2000). Thus, we emphasize that the fundamentals of preventive hemoglobinopathies program comprises the dissemination of information to the public, recognition of heterozygotes, neonatal diagnosis and genetic counselling. This includes enlightenment activities bearer of change clearly shall be carried out by specialist or geneticist with specific educational information (Zamaro et al., 2002).
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One-step genetic correction of hemoglobin E/beta-thalassemia patient-derived iPSCs by the CRISPR/Cas9 system

One-step genetic correction of hemoglobin E/beta-thalassemia patient-derived iPSCs by the CRISPR/Cas9 system

The study was approved by the Siriraj Institutional Re- view Board (no. Si248/2011), in accordance with the Helsinki Declaration of 1975. All patients were provided with an explanation and with a participant information sheet and signed the informed consent. Skin biopsies were collected from HbE/β-thalassemia patients for further mutation analysis and isolation of fibroblasts. Briefly, the skin specimens were washed with sterile phosphate buffered saline (PBS) containing 25 U/ml penicillin, 25 μg/ml streptomycin, chopped into small pieces of 1 mm 3 and transferred into a T-25 tissue culture flask containing DMEM supplemented with 10% fetal bovine serum (FBS) (Lonza, Switzerland), 2 mM GlutaMAX™ and 25 U/ml penicillin, 25 μg/ml streptomycin. Fibroblasts were subcultured once every 5 days or whenever they reached 80% confluency by incu- bation with 0.25% Trypsin for 2 min. Generation and characterization of Eβ-iPSCs from a HbE/β-thalassemic patient’s HDFs were performed as described previously [15]. iPSCs were maintained in mTeSR™1 medium (StemCell Technologies, Canada) on Matrigel™-coated (BD Bioscience, USA) plates and subcultured using 1
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Benefits of chronic blood transfusion in hemoglobin E/β thalassemia with pulmonary arterial hypertension

Benefits of chronic blood transfusion in hemoglobin E/β thalassemia with pulmonary arterial hypertension

The baseline characteristics were compared using exact probability tests for categorical variables; Student’s t-test or Wilcoxon rank-sum test was used to compare the mean dif- ference of continuous variables. Propensity score adjustment was used to control confounding by chronic blood transfusion indication and contraindication. Propensity scores for receiv- ing chronic blood transfusions versus occasional transfusions were calculated from a logistic regression model that esti- mated the likelihood of receiving chronic blood transfusions based on the observed patient characteristics. Gaussian and an exponential risk regression were carried out. Uni-variable and multivariable regression analyses were used to evaluate the effects of chronic blood transfusions. Data are presented by frequency, percentage, mean, median, standard deviation (SD), range, beta coefficient, 95% confidence interval, and P-value. All statistical analyses were two-tailed. A P-value of 0.05 was considered statistically significant.
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Molecular analysis of the beta thalassemia phenotype associated with inheritance of hemoglobin E (alpha 2 beta2(26)Glu leads to Lys)

Molecular analysis of the beta thalassemia phenotype associated with inheritance of hemoglobin E (alpha 2 beta2(26)Glu leads to Lys)

Inheritance of the gene for betaE-globin is associated with hypochromia and microcytosis, reminiscent of typical heterozygous beta-thalassemia. Patients with hemoglobin (Hb)E- beta-thalassemia exhibit clinical phenotypes of severe beta-thalassemia, a circumstance not encountered in other compound heterozygous states for structural beta-chain mutations and beta-thalassemia. We have analyzed the kinetics of globin synthesis and the levels of globin messenger (m) RNA accumulation in patients with Hb E-beta-thalassemia and Hb E trait. The initial rate of beta-globin synthesis (betaE/alpha=0.20-0.34) was less than
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Beta-thalassemia

Beta-thalassemia

Treatment of individuals with thalassemia intermedia is symptomatic [4,85]. As hypersplenism may cause wors- ening anemia, retarded growth and mechanical distur- bance from the large spleen, splenectomy is a relevant aspect of the management of thalassemia intermedia. Risks associated with splenectomy include an increased susceptibility to infections mainly from encapsulated bac- teria (Streptococcus Pneumoniae, Haemophilus Influen- zae and Neisseria Meningitidis) and an increase in thromboembolic events. Prevention of post-splenectomy sepsis includes immunization against the above men- tioned bacteria and antibiotic prophylaxis as well as early antibiotic treatment for fever and malaise. Because of the elevated prevalence of cholelithiasis and the risks of cholecystitis in splenectomised patients, the gallbladder should be inspected during splenectomy and removed in case with or to prevent gallstones. Treatment of extramedullary erythropoietic masses, detected by mag- netic resonance imaging, is based on radiotherapy, trans- fusions, or hydroxycarbamide. Once leg ulcer has developed, it is very difficult to manage. Regular blood transfusions, zinc supplementation and pentoxifylline, and the use of an oxygen chamber have been proposed for ulcer treatment. Hydroxycarbamide also has some benefit, either alone or with erythropoietin. Recently promising results have been obtained with platelet derived growth factor. Since patients with thalassemia intermedia have a high risk of thrombosis, exacerbated by splenectomy, it is important to be aware of thrombotic complications. Recommended treatment options include proper anticoagulation prior to surgical or other high- risk procedures, platelet anti-aggregating agents in case of thrombocytosis (platelet count higher than 700,000/ mm 3 ) and low molecular weight heparin in patients with
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Hemoglobin Indianapolis (beta 112[G14] arginine)  An unstable beta chain variant producing the phenotype of severe beta thalassemia

Hemoglobin Indianapolis (beta 112[G14] arginine) An unstable beta chain variant producing the phenotype of severe beta thalassemia

Hemoglobin (Hb) Indianapolis is an extremely labile beta-chain variant, present in such small amounts that it was undetectable by usual techniques. Clinically, it produces the phenotype of severe beta-thalassemia. Biosynthetic studies showed a beta:alpha ratio of 0.5 in reticulocytes and about 1.0 in marrow after a 1-h incubation. These results, similar to those seen in typical heterozygous beta-thalassemia, suggested that betaIndianapolis was destroyed so rapidly that its net synthesis was essentially zero. To examine the kinetics of globin synthesis, reticulocyte incubations of 1.25--20 min were performed with [3H]leucine. The betaIndianapolis:beta A ratio at 1.25 min was 0.80 suggesting that beta Indianapolis was synthesized at a near normal rate. At 20 min, this ratio was 0.46 reflecting rapid
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Homozygous delta-beta Thalassemia in a Child: a Rare Cause of Elevated Fetal Hemoglobin

Homozygous delta-beta Thalassemia in a Child: a Rare Cause of Elevated Fetal Hemoglobin

Delta-beta thalassemia (δβ-thalassemia), a relatively rare form of thalassemia, is characterized by lack of β and δ-globin chain production (1,4). This reduction in production is usually caused by deletion of δ and β structural genes(7).Non-deletional δβ-thalassemia has also been described, which results from presence in cis of 2 different nucleotide substitutions in promoter of Aγ and β-globin gene(7).Studies of globin chain synthesis have shown that α/non-α chain imbalance in δβ-thalassemia is less pronounced than in β- thalassemia(8). Mutations responsible for δβ-
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Prediction of Optimum Treatment in Beta-Thalassemia Patients with Hepatitis C Virus Infection

Prediction of Optimum Treatment in Beta-Thalassemia Patients with Hepatitis C Virus Infection

This prospective study showed that low dose ribavirin in chronically HCV infected thalassemia patients is safe, tolerable and effective. Our primary efficacy analysis showed that SVR rate was significantly higher in group (A) patients who received combination therapy with low dose ribavirin in comparison with patients of group (B) who received monotherapy. In addition, HCV-PCR baseline, Ferritin and age were predictors of SVR rate in the total studied population. These findings are consistent with the results of previous studies [12][24]. Moreover, by close observation and frequent transfusion, the rate of severe hemoglobin drop can be minimized. As presented in Table 1 most of major predictors of virological response including HCV RNA level, sex, HCV-PCR, age and liver histological findings appeared to be similar in both groups [24]. However, someone can argue that lack of randomization might underestimate the efficacy of Peg-IFN monotherapy or overestimate the safety of ribavirin. The reason is that patients with more severe thalassemia might have denied ribavirin treatment. This is unlikely in our opinion because comparison of baseline serum ferritin level shows that those who accepted ribavirin therapy had a significant elevated serum ferritin level and subsequently a more severe thalassemia than those who declined to receive ribavirin [25], our study shows 74% ferritin baseline levels in both groups. This analysis indicated that the major impact of low dose ribavirin was in thalassemia major patients with age older than 24 years of age, a low serum ferritin (< 2600 ng/mL), an elevated ALT and liver fibrosis of 0-4 HAI, history of splenectomy and viral load ≤ 600,000 IU/mL. This later observation has been reported by others as well [12].
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Globin chain synthesis in the alpha thalassemia syndromes

Globin chain synthesis in the alpha thalassemia syndromes

hemoglobin H disease, alpha thalassemia trait, and the “silent carrier” state were incubated with leucine- 14 C for definition of relative rates of production of alpha and beta chains in these disorders. The chains were separated by carboxymethyl cellulose chromatography in the presence of 8 M urea and dithiothreitol. Their absorptions at 280 mµ were determined and their radioactivities measured in a liquid scintillation spectrometer. After correction for differences in extinction coefficients, the specific activities of the widely separated alpha and beta peaks were determined. In 11 nonthalassemic individuals, the alpha/beta specific activity ratios were found to be 1.02±0.07; in nine patients with alpha thalassemia trait, 0.77±0.05; in six patients with hemoglobin H disease, 0.41±0.11; and in four “silent carriers,” 0.88 with a range of 0.82-0.95. The results show that in peripheral blood, alpha chain
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Hemoglobin Messenger RNA from Human Bone Marrow ISOLATION AND TRANSLATION IN HOMOZYGOUS AND HETEROZYGOUS β THALASSEMIA

Hemoglobin Messenger RNA from Human Bone Marrow ISOLATION AND TRANSLATION IN HOMOZYGOUS AND HETEROZYGOUS β THALASSEMIA

thalassemia, sickle cell trait, double heterozygosity for beta thalassemia and sickle cell trait, as well as from a patient with normal hemoglobin synthesis but with an elevated reticulocyte count secondary to hereditary spherocytosis. The mRNA was prepared for assay in an mRNA-dependent rabbit reticulocyte cell-free system and the amount of alpha and beta globin chains synthesized was determined by carboxymethylcellulose column

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Genotype&ndash;phenotype correlation among beta-thalassemia and beta-thalassemia/HbE disease in Thai children: predictable clinical spectrum using genotypic analysis

Genotype&ndash;phenotype correlation among beta-thalassemia and beta-thalassemia/HbE disease in Thai children: predictable clinical spectrum using genotypic analysis

The genotype and phenotype correlation was studied in our patients. All homozygous and compound heterozygous beta-thalassemia patients were in thalassemia major. Sixty- three beta-thalassemia/HbE patients were classified in 58 thalassemia major and 4 thalassemia intermedia (Table 3). The HBB:c.126_129delCTTT mutation was noted in 27 beta-thalassemia/HbE patients which was divided into 26 thalassemia major patients and 1 thalassemia intermedia patient. Interestingly, one thalassemia intermedia patient had hemoglobin F 20.8%, which was lower than the aver- age numbers of thalassemia major patients (46.31 ± 23.82%). Further evaluation on this thalassemia intermedia patient also found concomitant alpha-globin gene mutation (Hemoglo- bin Constant Spring, Hb CS) which could explain the lower hemoglobin F level and less severe clinical symptoms in this patient. The HBB:c.92 + 1G > T mutation was found in 4 beta- thalassemia/HbE patients: 3 thalassemia major patients and 1 thalassemia intermedia patient. The 3.4 kb deletion was found in 2 beta-thalassemia/Hb E patients and both of them had clinical severity as thalassemia major. The HBB:c.-78A > G and HBB:c.59A > G were identified and both patients were classified as thalassemia intermedia.
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The inherited disorders of hemoglobin are responsible for an extremely complex series of clinical phenotypes. Sickle cell anaemia and thalassemia can cause chronic ill-health and life-threatening situations. Present study was carried out at Dharwad of North Karnataka. The practice of consanguineous marriages is an accepted socio- cultural phenomenon in this region. This study was hospital-based and the paediatric cases of hemoglobinopathies were identified based on clinical data, family history, red blood cell indices and hemoglobin electrophoresis. Out of the fifty cases , twenty chidren were carriers of beta- thalassemia trait and fifteen children were suffering from beta-thalassemia major. Two cases of sickle cell trait and lone case of a compound heterozygote for HbS/beta-thalassemia were also identified. Families of four cases of hemoglobinopathies were studied in detail to identify the carriers of abnormal hemoglobins. Ten out of fifty children of the study were products of consanguineous mating. The population of Dharwad appears to be a repository of thalassemia. An extensive screening of the population is needed to assess the prevalence of hemoglobinopathies, which will help in identification of carriers of hemoglobinopathies and further in taking adequate therapeutic and preventive measures.
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Molecular characterization of β-thalassemia intermedia in the West Bank, Palestine

Molecular characterization of β-thalassemia intermedia in the West Bank, Palestine

Analysis of the Gγ-globin gene XmnI SNP showed that three patients were homozygous and one patient was heterozygous for this SNP, three of them have the β 0 /β 0 genotype and one has the β 0 /β + (in addition to –α 3.7 / αα) and the effect of this SNP was clearly illustrated by the high levels of HbF in these patients. The role of Gγ-globin gene XmnI SNP in increasing HbF levels and moderation of thalassemia phenotype is widely known and reported in many earlier studies [4, 14, 35]. The XmnI polymorphism is one of three major HbF quanti- tative trait loci (QTLs) responsible for HbF variation, and it leads to a less severe phenotype by increasing γ-chain production, which helps to neutralize un- bounded α-chains [15, 36]. However, in the present study the G γ-globin gene XmnI polymorphism was not detected in any patient with the genotype β + /β + or the β + /β wt
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Influence of hemoglobin precipitation on erythrocyte metabolism in alpha and beta thalassemia

Influence of hemoglobin precipitation on erythrocyte metabolism in alpha and beta thalassemia

Beta thalassemia young cells contained less hemoglobin F and, after splenectomy, more inclusions than old cells. In addition, they had markedly increased glycolysis and HMPS activity. GSH was randomly distributed. Potassium flux was increased in younger cells and particularly increased when inclusions appeared in younger cells after splenectomy.

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EFFICACY OF HEMOGLOBIN LEVEL IN DIAGNOSING OF BETA THALASSEMIA

EFFICACY OF HEMOGLOBIN LEVEL IN DIAGNOSING OF BETA THALASSEMIA

Level of HbA2 more than 4% is the reliable parameter to identify β- thalassemia carrier. However, in some cases the level is not typically increased hence leading to diagnostic dilemma. Thus the objectives of this study were to evaluate the existence of β- thalassemia among borderline HbA2 sample of population of Lahore. Out of 11,790 samples received for thalassemia screening, 405 (3.4%) were found to have borderline HbA2 level. Out of this, 117(28.9%) samples were selected by simple random sampling for PCR. Multiplex ARMS-PCR was used to detect β-globin gene mutation and multiplex gap PCR for α-globin genes deletion. The result revealed 36 (30.8%) had β- globin gene mutations, 8 (6.8%) had α-globin gene deletions and 1 (0.9%) had coexistence of α and β-globin gene defects. The commonest gene mutation detected were CD 19 (A-G), detected from 17 (45.9%) samples, followed by 9 (24.3%) with IVS 1-1 (G-A) mutation, 5 (13.5%) with Poly A mutation and 1 (2.7%) showed CAP +1 (A-C) mutation. Two samples (5.4%) showed mutations of Poly A and CD19, 2 (5.4%) showed mutation of IVS 1-1 and CD 19 while 1 (2.7%) showed IVS 1-5 and CD 19 mutations. This study showed 10 (27.0%) positive molecular results even though the HbA2 level was at only 3.0%. There was significant number of people with HbA2 between 3.0% and 3.9% and confirmed as thalassemia carriers by PCR. This data may suggest the level of HbA2 need to be revised to ensure the success of thalassemia screening programme in our population.
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In Patients with Minor Beta-Thalassemia, Cognitive Performance Is Related to Length of Education, But not to Minor Beta-Thalassemia or Hemoglobin Levels

In Patients with Minor Beta-Thalassemia, Cognitive Performance Is Related to Length of Education, But not to Minor Beta-Thalassemia or Hemoglobin Levels

Our first hypothesis was that individuals with minor beta-thalassemia would have higher hemoglobin levels than healthy controls, and this was confirmed. While the result is unsurprising, it helped us ascertain that people with minor beta-thalassemia could be clearly distinguished from healthy controls at a biological level . Our second hypothesis was that individuals with minor beta-thalassemia would perform more poorly on cognitive tasks than healthy controls. This hypothesis was not supported. Thus, the present results are at odds with previously published findings for adults (11-13). However, our findings are consistent with evidence from studies of children (8, 10), which revealed no deficits in cognitive functioning associated with beta-thalassemia. We do not have the data that might provide a deeper understanding of the lack of difference we found, although in previous studies (11-13) a straightforward psychophysiological rationale was missing. Nevruz et al. (11) assessed cognitive performance with an auditory test, while they were not interested in the test performance. However, in the P300 potentials, Zangiabadi et al. (12) found lower performances in patients with minor beta thalassemia in subtests of arithmetic and vocabulary and picture completion, while on the non-verbal scale, they found no significant difference between the two groups. However, Zangiabadi et al. (12) and Monastero et al. (22) did not control for length of education.
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Defect in messenger RNA for human hemoglobin synthesis in beta thalassemia

Defect in messenger RNA for human hemoglobin synthesis in beta thalassemia

reticulocyte lysates of patients with homozygous beta thalassemia and sickle cell anemia. The messenger RNA stimulated the synthesis of human globin chains by a cell-free system derived from Krebs mouse ascites cells. In the presence of beta thalassemia messenger RNA, the system synthesized much less beta chain than alpha chain whereas in the presence of sickle cell anemia messenger RNA, nearly equal amounts of alpha and beta chains were synthesized. The beta/alpha synthetic ratios obtained in the cell-free system were similar to those obtained by incubating intact beta thalassemia and sickle cell anemia reticulocytes in the presence of radioactive leucine. The experiments provide direct
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Sickle Cell Beta Thalassemia: A Rare Entity

Sickle Cell Beta Thalassemia: A Rare Entity

The hemoglobinopathies are genetic disorders characteri- zed by the production of structurally defective hemoglo- bin (Hb), and in thalassemia, there is reduction in rate of production of normal Hb due to absent or decreased synthesis of one or more types alpha(α) or beta (β) of globin polypeptide chains. 2 Sickle cell disorders (SCD)

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JOURNAL OF CLINICAL AND DIAGNOSTIC RESEARCH

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This prospective family study is based on nine index cases of sickle cell-beta-thalassemia and seven index cases of hemoglobin-E-beta- thalassemia. They were selected out of 1500 routinely referred cases, sent for investigation for the cause of anemia and suspected to be suffering from hemoglobinopathies before first blood transfusion, from different peripheral Primary Health Centres (PHCs) and hospitals in the state of Orissa during the period between 2001 to April 2006. Details diagnosis and analysis of the referral cases in Orissa have already been reported elsewhere [9],[10]. All the above mentioned index cases and their other available family members such as parents, brothers and sisters were also subjected to clinical examination and investigation for the cause of anemia and genetic/marriage counseling after taking informed consent. In all, there were 30 subjects related with sickle cell-β-thalassemia and 22 for hemoglobin E-β-thalassemia. Background information for each family such as name, age, sex, caste, native place, reproductive history, family pedigree, and clinical signs and symptoms were recorded.
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Haematological and Genetic Characterization of Thalassemia Intermedia in Tank and South Waziristan Agency of Khyber Pakhtun Khwa

Haematological and Genetic Characterization of Thalassemia Intermedia in Tank and South Waziristan Agency of Khyber Pakhtun Khwa

The age at diagnosis of patients of thalassemia intermedia is in range of 1.5 year to 7 years as compared to patients of thalassemia major having the age at diagnosis less than one year [ 14, 15 ] . The present ages of thalassemia intermedia patients were in range of 4 years to 35 years. Unlike thalassemia major, they were not regularly transfused. A small number of patients had 7-10.4 g/dl Hb at the age of diagnosis or just before first transfusion as compared to the patients of thalassemia major, which had hemoglobin level of less than 6 g/dl at the age of diagnosis, or just before first transfusion. The patients of thalassemia intermedia developed few typical symptoms such as splenomegaly, hepatomegaly or skeletal changes usually seen in more severe forms. Only 6 patients had splenectomy. The therapeutic interventions for some of these patients have been folic acid and desferol injections (desfersxamine). Very interestingly, these patients had large amount of HbF in the range of 9%-22% and HbA2 in the range of 3.5% to 5.8% as compared to the patients of thalassemia major, which had less amount of HbF in the range of 1.9-2.2% in the blood taken just before transfusion. We collected blood samples in accordance with criteria for thalassemia intermedia but, after molecular characterization, 5 patients were found as of thalassemia major as their genotypes were β 0/ β 0. Some of the patients of thalassemia intermedia were made transfusion depentent besides the fact that they did not require regular transfusion (Table 1). Hence, in our opinions these values do not indicate the patient’s bone marrow condition because patients get transfusion before their Hb level dropped below 10 g/dl. Therefore these values are a combination of patient’s blood and transfused blood. The parents of most patients
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