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Query: UMLS:C0019045 (
hemoglobinopathies
)
2,704
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Diabetes mellitus (DM) is a frequent disorder affecting individuals of all ages. Glycohemoglobin (GHb) has a key role in the assessment of glycemic control in diabetic patients. Generally, GHb is measured as hemoglobin (Hb) A1C and is the result of an irreversible non-enzymatic glycation of the beta chain of hemoglobin A. HbA1C is used routinely to assess long term glycemic control in patients with DM. A variety of patient- and laboratory-related factors can adversely affect the measurement of HbA1C in patients harboring Hb variants or derivatives. In this article, problem of using hemoglobin A1C measurement in endemic area of
hemoglobinopathy
is addressed.
Prim Care Diabetes 2007
Sep
PMID:Problem of using hemoglobin A1C measurement in endemic area of hemoglobinopathy. 1863 40
A major goal of
hemoglobinopathy
research is to develop treatments that correct the underlying molecular defects responsible for sickle cell disease and beta-thalassemia. One approach to achieving this goal is the pharmacologic induction of fetal hemoglobin (HbF). This strategy is capable of inhibiting the polymerization of sickle hemoglobin and correcting the globin chain imbalance of beta-thalassemia. Despite this promise, none of the currently available HbF-inducing agents exhibit the combination of efficacy, safety, and convenience of use that would make them applicable to most patients. The recent success of targeted drug therapies for malignant diseases suggests that this approach could be effective for developing optimal HbF-inducing agents. A first step in applying this approach is the identification of specific molecular targets. However, while >70 HbF-inducing agents have been described, neither molecular mechanisms nor target molecules have been definitively verified for any of these compounds. To help focus investigation in this area, we have reviewed known HbF-inducing agents and their proposed mechanisms of action. We find that in many cases, current models inadequately explain key experimental results. By integrating features of the erythropoietic stress model of HbF induction with data from recent intracellular signaling experiments, we have developed a new model that has the potential to explain several findings that are inconsistent with previous models and to unify most HbF-inducing agents under a common mechanism: cell stress signaling. If correct, this or related models could lead to new opportunities for development of targeted therapies for the beta-
hemoglobinopathies
.
Exp Hematol 2008
Sep
PMID:A cell stress signaling model of fetal hemoglobin induction: what doesn't kill red blood cells may make them stronger. 1871 15
Beta-thalassaemia is the most common
hemoglobinopathies
in our region with treatment of regular blood transfusion. Iron overload and hemosiderosis can cause organ involvement. Recent studies have focused on pulmonary involvement and pathophysiology of lung damage. The goal of this study was to investigate the pulmonary abnormalities in thalassemic patients in relation with sign and symptoms and iron overload. The authors studied pulmonary function test (PFT) at the Adult Thalassemia Clinic in Tehran. The history of blood transfusion, iron chelation, respiratory problems, and drug usage was taken. Physical examination, PFT, arterial blood gas (ABG), and chest X-ray (CXR) were done. In total, 139 patients were studied. The mean age was 21.1 years and mean duration of transfusion was 18 years. It was found that 133 patients (95.7%) did not have respiratory problems and only 6 (4.3%) had some respiratory complaints. In CXR, 100 patients (89.3%) had normal lung pattern and others (10.7%) had variable degrees of abnormal lung pattern. In ABG, mean of Po(2) was 73.5% and mean of O(2) saturation was 90.6%. In PFT, 101 patients (72.7%) had restrictive pattern, 35 (25.1%) had normal pattern, and 3 (2.2%) had combined pattern. According to vital capacity, the patients were placed in five categories: 54 patients (38.8%) normal, 37 (26.6%) mild, 35 (25.3%) moderate, 10 (7.2%) severe, and 3 (2.1%) extremely severe pulmonary deficit. There was no statistical significance between PFT results with all variables studied, except duration of blood transfusion, which may be considered a indirect effect of iron load (p = .05, r = .361). According to these results, restrictive pattern was the most common finding (72.7%) in PFT, while 95.7% of patients had no respiratory complaint, and in the chest X-ray group, 89.3% had normal pattern. The authors conclude that the lung may be considered a site for organ damage, and alteration of pulmonary function may be expected in transfusion-dependent patients in spite of no pulmonary symptoms or normal CXR. In recent years, because of new iron chelating drugs, doctors can expect thalassemic patients to have a long life-time and need to increase their quality of life. One way to do this is to evaluate the respiratory system by PFT to prevent the squeal of pulmonary disease.
Pediatr Hematol Oncol 2008
Sep
PMID:Pulmonary function test in transfusion-dependent beta-thalassemia patients. 1872 79
Hemoglobinopathies
are hereditary autosomic recessive diseases. A total of 70 943 samples of whole blood collected by heel prick in filter paper (S&S 903) from throughout Costa Rica (October 2005-October 2006) were analyzed to detect variants of hemoglobin by the iso-electric focusing technique. Eight hundred ninety one cases presented some variant, for a frecuency of 1/79. Five cases are homozygous for hemoglobin S (sickle cell disease) and one shows the double heterozygous genotype SC. In this study the S and C variants of hemoglobin, although with some local differences, are widespread all over the country. Thus, the prevention of new cases is important through the testing of hemoglobin in the Costa Rican National Newborn Screening Program, together with a Interdisciplinary National Program of Education for the disease and carrier status (AS/AC) for patients, families and medicar personnel. This is the basis for proper genetic counseling, to improve treatment and to reduce morbi-mortality.
Rev Biol Trop 2008
Sep
PMID:[Abnormal haemoglobins in the newborn human population of Costa Rica]. 1941 22
Population migration has led to the global dispersion of human
hemoglobinopathies
and has precipitated a need for their identification. An effective mass spectrometry-based procedure involves analysis of the intact alpha- and beta-globin chains to determine their mass, followed by location of the variant amino acid residue by direct analysis of the enzymatically digested chains and low-energy collision induced dissociation of the variant peptide. Using this procedure, a variant was identified as either beta54Val-->Leu or beta54Val-->Ile, since the amino acids leucine and isoleucine cannot be distinguished using low-energy collisions. Here, we describe how hot electron capture dissociation on a Fourier transform-ion cyclotron resonance mass spectrometer was used to distinguish isoleucine from leucine and identify the mutation as beta54(D5)Val-->Ile. This is a novel variant, and we have named it Hb Askew.
J Am Soc Mass Spectrom 2009
Sep
PMID:Hot electron capture dissociation distinguishes leucine from isoleucine in a novel hemoglobin variant, Hb Askew, beta54(D5)Val-->Ile. 1953 97
Therapeutic regulation of globin genes is a primary goal of translational research aimed toward
hemoglobinopathies
. Signal transduction was used to identify chromatin modifications and transcription factor expression patterns that are associated with globin gene regulation. Histone modification and transcriptome profiling were performed using adult primary CD34(+) cells cultured with cytokine combinations that produced low versus high levels of gamma-globin mRNA and fetal hemoglobin (HbF). Embryonic, fetal, and adult globin transcript and protein expression patterns were determined for comparison. Chromatin immunoprecipitation assays revealed RNA polymerase II occupancy and histone tail modifications consistent with transcriptional activation only in the high-HbF culture condition. Transcriptome profiling studies demonstrated reproducible changes in expression of nuclear transcription factors associated with high HbF. Among the 13 genes that demonstrated differential transcript levels, 8 demonstrated nuclear protein expression levels that were significantly changed by cytokine signal transduction. Five of the 8 genes are recognized regulators of erythropoiesis or globin genes (MAFF, ID2, HHEX, SOX6, and EGR1). Thus, cytokine-mediated signal transduction in adult erythroid cells causes significant changes in the pattern of globin gene and protein expression that are associated with distinct histone modifications as well as nuclear reprogramming of erythroid transcription factors.
Blood 2009
Sep
10
PMID:Cytokine-mediated increases in fetal hemoglobin are associated with globin gene histone modification and transcription factor reprogramming. 1959 82
Salmonella species are rare bacterial isolates in osteomyelitis. This article describes a case of an otherwise healthy, active duty male military member with an insidious onset of right knee pain during a deployment to Kuwait. His work-up revealed an infectious process in the distal femur. Operative treatment and intravenous antibiotics resolved the infection. Intraoperative cultures revealed the rare isolate Salmonella enterica serotype C2 (Newport). Postoperative medical management revealed new-onset diabetes mellitus, possibly making this otherwise healthy host susceptible to this rare infection. Salmonella are gram-negative bacteria. Infection with nontyphoidal Salmonella species most commonly manifests as intestinal illness. Although it may be difficult for clinicians to accurately predict this rare entity as the causative organism in osteomyelitis, they may be aided by a history of travel to endemic regions or exposure to animal carriers. Comorbidities that seem to increase susceptibility include diabetes mellitus, human immunodeficiency virus,
hemoglobinopathies
, and immunosuppression. Blood cultures are reported to be frequently positive in cases of Salmonella osteomyelitis. Identification of Salmonella species from intraoperative cultures should prompt consultation with the infectious disease department for culture-specific antibiotic tailoring. Many common antibiotic agents active against gram-negative organisms seem efficacious. As in this case, following the basic tenets of osteomyelitis management should lead to an acceptable outcome.
Orthopedics 2009
Sep
PMID:Salmonella osteomyelitis in new-onset diabetes mellitus. 1975 Sep 96
In beta-
hemoglobinopathies
, such as beta-thalassemia (thal) and sickle cell anemia, the primary defects are mutations in the beta-globin gene. However, many aspects of the pathophysiology are mediated by oxidative stress. Fermented papaya preparation (FPP), a natural health food product obtained by biofermentation of carica papaya, has been shown to limit oxidative stress both in vitro and in vivo. We studied the effect of FPP on two groups of beta-thal patients: beta-thal, major and intermedia, (in Israel) and E-beta-thal (in Singapore). The results indicated that in both groups FPP treatment increased the content of reduced glutathione (GSH) in red blood cells (RBC), and decreased their reactive oxygen species (ROS) generation, membrane lipid peroxidation, and externalization of phosphatidylserine (PS), indicating amelioration of their oxidative status, without a significant change in the hematological parameters. Since the turnover of the erythron is relatively slow, it is possible that longer duration of treatment, probably with the addition of an iron chelator, is required in order to achieve the latter goals.
Phytother Res 2010
Sep
PMID:Amelioration of oxidative stress in red blood cells from patients with beta-thalassemia major and intermedia and E-beta-thalassemia following administration of a fermented papaya preparation. 2108 79
Hemoglobin (Hb) Q-Thailand, Hb E, and other forms of thalassemia are prevalent in Southeast Asia including China. We report a hitherto undescribed condition in which four forms of Hb defects co-segregate. The proband was a 20-year-old Chinese man who presented with moderate hypochromic microcytosis with Hb 73 g/l, hematocrit (Hct) 27.0%, mean corpuscular volume 57.6 fl, mean corpuscular hemoglobin 15.5 pg, and mean corpuscular hemoglobin concentration (MCHC) 268.0 g/l. Both Hb electrophoresis and high-performance liquid chromatography analysis revealed abnormal Hbs. DNA analysis demonstrated that the proband was a double heterozygote of Hb Q-Thailand and Hb E in combination with alpha(0)-thalassemia and Southeast Asian-type hereditary persistence of fetal hemoglobin (SEA-HPFH). Family study identified that her father was a double heterozygote for Hb Q-Thailand and Hb E, whereas her mother was a heterozygote for SEA-HPFH with alpha(0)-thalassemia. Moreover, his brother was a classical Hb QH disease patient. The genotype-phenotype relationship observed in this Chinese family with complex thalassemia syndromes is presented. This work will provide some clinical implications for molecular diagnosis for complex
hemoglobinopathies
.
Ann Hematol 2010
Sep
PMID:Complex interaction of Hb Q-Thailand and Hb E with alpha(0)-thalassemia and hereditary persistence of fetal hemoglobin in a Chinese family. 2033 23
Previous studies have shown that subjects with sickle cell trait (SCT), alpha-thalassemia (alpha-t), and the dual
hemoglobinopathy
(SCT/alpha-t) manifest subtle, albeit significant, differences during exercise. To better understand such differences, we assessed skeletal muscle histomorphological and energetic characteristics in 10 control HbAA subjects (C), 5 subjects with alpha-t (alpha-t), 6 SCT carriers (SCT) and 9 SCT carriers with alpha-t (SCT/alpha-t). Subjects underwent a muscle biopsy and also performed an incremental maximal exercise and a time to exhaustion test. There were no observable differences in daily energy expenditure, maximal power output (Pmax), or time to exhaustion at 110% Pmax (Tex) among the groups. Blood lactate concentrations measured at the end of the Tex, muscle fiber type distribution, and mean phosphofructokinase (PFK), lactate dehydrogenase (LDH), beta-hydroxyacyl-CoA-dehydrogenase (HAD), and citrate synthase (CS) activities were all similar among the four groups. However, SCT was associated with a lower cytochrome-c oxidase (COx) activity in type IIa fibers (P<0.05), and similar trends were observed in fiber types I and IIx. Trends toward lower creatine kinase (CK) activity (P=0.0702) and higher surface area of type IIx fibers were observed in SCT (P=0.0925). In summary, these findings support most of the previous observations in SCT, such as 1) similar maximal power output and associated maximal oxygen consumption (VO2max) values and 2) lower exercise performances during prolonged submaximal exercise. Furthermore, performances during short supramaximal exercise were not different in SCT. Finally, the dual
hemoglobinopathy
condition does not seem to affect muscle characteristics.
J Appl Physiol (1985) 2010
Sep
PMID:Skeletal muscle structural and energetic characteristics in subjects with sickle cell trait, alpha-thalassemia, or dual hemoglobinopathy. 2057 43
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