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Query: UMLS:C0019045 (hemoglobinopathies)
 2,704 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sickle cell-related hemoglobinopathies present challenges for clinical management during pregnancy, labor, delivery, and the postpartum course because perinatal morbidity remains a significant practice concern. Nursing strategies that strive for synthesis of knowledge pertaining to pathophysiology, genetic counseling, life events that have affected the patient's health history, treatment modalities, and psychosocial needs may improve obstetric and neonatal outcomes. Clinical management strategies for the prenatal, intrapartum, and postpartum courses are provided. Nursing intervention strategies such as follow-up teaching, involvement of the partner and support network in aspects of care, and patient advocates, in conjunction with independent nursing practice activities involving emotional support and measures to alleviate symptoms associated with disease manifestations, are cornerstones in the contribution of nursing to the multidisciplinary care of the pregnant woman with sickle cell disease and trait.
J Perinat Neonatal Nurs 1995 Sep
PMID:Clinical nursing management of sickle cell disease and trait during pregnancy. 763 10

Red blood cell (RBC) membranes from patients with the thalassemic and sickle hemoglobinopathies carry abnormal deposits of iron presumed to mediate a variety of oxidative-induced membrane dysfunctions. We hypothesized that the oral iron chelator deferiprone (L1), which has an enhanced capacity to permeate cell membranes, might be useful in chelating these pathologic iron deposits from intact RBCs. We tested this hypothesis in vitro by incubating L1 with RBCs from 15 patients with thalassemia intermedia and 6 patients with sickle cell anemia. We found that removal of RBC membrane free iron by L1 increased both as a function of time of incubation and L1 concentration. Thus, increasing the time of incubation of thalassemic RBCs with 0.5 mmol/L L1 from 0.5 to 6 hours, enhanced removal of their membrane free iron from 18% +/- 9% to 96% +/- 4%. Dose-response studies showed that incubating thalassemic RBC for 2 hours with L1 concentrations ranging from 0.125 to 0.5 mmol/L resulted in removal of membrane free iron from 28% +/- 15% to 68% +/- 11%. Parallel studies with sickle RBCs showed a similar pattern in time and dose responses. Deferoxamine (DFO), on the other hand, was ineffective in chelating membrane free iron from either thalassemic or sickle RBCs regardless of dose (maximum, 0.333 mmol/L) or time of incubation (maximum, 24 hours). In vivo efficacy of L1 was shown in six thalassemic patients whose RBC membrane free iron decreased by 50% +/- 29% following a 2-week course of L1 at a daily dose of 25 mg/kg. As the dose of L1 was increased to 50 mg/kg/d (n = 5), and then to 75 mg/kg/d (n = 4), 67% +/- 14% and 79% +/- 11%, respectively, of their RBC membrane free iron was removed. L1 therapy--both in vitro and in vivo--also significantly attenuated the malondialdehyde response of thalassemic RBC membranes to in vitro stimulation with peroxide. Remarkably, the heme content of RBC membranes from L1-treated thalassemic patients decreased by 28% +/- 10% during the 3-month study period. These results indicate that L1 can remove pathologic deposits of chelatable iron from thalassemic and sickle RBC membranes, a therapeutic potential not shared by DFO. Furthermore, membrane defects possibly mediated by catalytic iron, such as lipid peroxidation and hemichrome formation, may also be alleviated, at least in part, by L1.
Blood 1995 Sep 01
PMID:Deferiprone (L1) chelates pathologic iron deposits from membranes of intact thalassemic and sickle red blood cells both in vitro and in vivo. 765 28

The human beta E-globin gene from HbE (beta 26 Glu-->Lys, G-->A) homozygote, a common hemoglobinopathy in China, was injected into the pronuclei of fertilized mouse eggs to prepare transgenic mice. A transgenic mouse bearing 16 copies of construct 5'.HS2 beta E has characteristics of typical transgenic mice. It has been verified that the presence of erythroid enhancer 5'HS2 is necessary for the high level expression of human beta E-globin gene in transgenic mice, indicating that the cis-element 5'HS2 is effective for abnormal beta-globin gene as well. Although the expression level of beta-globin gene was copy number-dependent as reported in previous studies, the average expression level per gene copy (12.1%) in transgenic mice bearing many copies of 5'HS2 beta E (16 copies) was significantly lower than that (79.7%) in transgenic mice bearing fewer copies of the gene (2 copies). The possible mechanisms for this decrease of expression are discussed. Novel hemoglobin tetramers which presumably consist of human beta E-globin chains and mouse endogenous alpha-globin chains have been assembled in transgenic mice.
Sci China B 1994 Sep
PMID:Expression of human beta E-globin gene with erythroid enhancer in transgenic mice. 799 81

Patients with sickle hemoglobinopathies are at risk for unique postoperative complications and increased mortality. Understanding the pathophysiology of these disorders is important for safe perioperative management. Because there is no animal model for sickle cell disease, understanding has progressed through in vitro studies and clinical observations. This review describes the clinical manifestations of the sickle hemoglobinopathies with special emphasis on current knowledge of pathophysiology. It also discusses issues of preoperative screening, transfusion, and postoperative care.
Am J Surg 1994 Sep
PMID:The pathophysiology of the sickle hemoglobinopathies and implications for perioperative management. 808 66

Twenty-two arthroplasties were performed in 14 patients with sickle cell hemoglobinopathy (SCH). There were 15 primary and seven revision procedures; none were lost to follow-up evaluation. In the primary arthroplasty group, there were two deaths in patients whose implants were functioning well. The remaining 13 hips had a mean follow-up period of 4.8 years. Failure occurred in five of these 13 hips (38%), four due to aseptic acetabular loosening and one due to sepsis. In the revision arthroplasty group, at a mean follow-up period of 5.3 years, failure occurred in three hips (43%), one due to acetabular loosening, one due to femoral loosening, and one due to sepsis. Perioperative complication rates were high in both groups. Femoral intramedullary sclerosis and bone altered by marrow hyperplasia were associated with intraoperative technical difficulties as well as problems with achieving long-term component fixation. Though total hip arthroplasty provides the most reliable measure of effective treatment in SCH, it carries a high risk of complications and failure.
Clin Orthop Relat Res 1993 Sep
PMID:Total hip arthroplasty in sickle cell hemoglobinopathy. 835 6

New reproductive genetics means recently developed techniques to prevent the birth of children with specific defects or genetic diseases by testing individuals for sickle cell anemia, the thalassemias, Tay-Sachs disease, cystic fibrosis, or Down syndrome. Third World health services have many deficiencies with high maternal mortality rates (30-40 fold higher than in developed countries), the low percentage of births delivered by health personnel, the high rates of low birth weight babies, and high child malnutrition and infant mortality rates. The main issues in women's reproductive health are fertility regulation, abortion, maternal mortality, sexually transmitted diseases, and infertility. As a result of expansion in contraceptive use worldwide, the total fertility rate in developing countries has declined from 6.1 in 1965 to 3.9 in 1990. It is estimated that, worldwide, 36-53 million induced abortions are performed each year, most of them in developing nations. WHO estimates that more than 500,000 women die each year because of complications of pregnancy, most in developing countries. More than 95% of the 13 million estimated deaths of children under 5 years of age have occurred in these countries. Approximately 200 million people carry a potentially pathologic hemoglobinopathy gene, and about 250,000 children are born every year with hemoglobinopathy, most of them in the developing world. Reproductive genetic testing in big cities and in private for-profit ventures cater to the socioeconomic elite. Amniocentesis is often misused for fetal sex determination to abort female fetuses in India. Currently, in Cuba virtually every pregnant woman is tested for sickle cell trait and maternal serum alpha-fetoprotein levels between 15 and 20 weeks of gestation. It is predicted that the judicious use of reproductive genetic testing will be possible when health and quality of life issues are addressed properly.
Clin Obstet Gynecol 1993 Sep
PMID:Reproductive health and genetic testing in the Third World. 840

Prenatal diagnosis is available for pregnancies at risk for virtually all inherited disorders of hemoglobin production. The field of reproductive genetics must confront many ethical, legal, and social concerns regarding its use, many of which derive from a woman's desire to bear children but legal right to abortion. The goal of more widespread utilization of prenatal diagnosis is sought in the context of questioning the ethical control to be exerted over the biological makeup of future generations. Its appropriate application would be facilitated greatly by the availability of reliable DNA markers of disease severity. Advances in fetal sampling and in detecting mutant globin genes have provided the safe, accurate methodology required for prenatal diagnosis. Chorionic villus sampling in the first trimester has become standard practice, but second trimester amniocentesis also is used for sampling fetal DNA. The use of preimplantation diagnosis and testing fetal cells from the maternal circulation will soon be practical. DNA-based detection of globin gene mutations has been facilitated greatly by the polymerase chain reaction revolution, and several reliable diagnostic methods are available. Polymerase chain reaction-based methods rely on restriction analysis, allele-specific hybridization or amplification, DNA sequence analysis, and new non-polymerase chain reaction methods for DNA amplification in vitro. These methods are available for detecting hemoglobinopathy, thalassemia, and thalassemic-hemoglobinopathy genes that affect alpha- or beta-globin loci.
Hemoglobin 1995 Sep
PMID:Advances in the prenatal and molecular diagnosis of the hemoglobinopathies and thalassemias. 853 29

During the last decade it has been shown that patients with major sickle hemoglobinopathies can experience a normal reproductive outcome. This has been accomplished with early aggressive prenatal care, effective counseling, and appropriate intervention by providers with a high index of suspicion for factors that lead to untoward outcomes in such women. Because controversy surrounds the use of transfusion therapy for pregnant patients with sickle cell disease, individualization should depend on patient circumstances and provider experience because this is a key factor in the management of these women. New therapies for those with major sickle hemoglobinopathy are on the horizon, but their use in pregnancy awaits further evaluation.
Clin Obstet Gynecol 1995 Sep
PMID:Pregnancy complicated by sickle hemoglobinopathy. 861 59

Two diabetic patients with unusual high levels of glycosylated hemoglobin measured by ion exchange chromatography are described. Further studies revealed a persistence of fetal hemoglobin in both cases. This condition produces falsely high levels of glycosylated hemoglobin, when ion exchange chromatography is used. These cases may be overtreated with risk of hypoglycemia. Patients with inappropriate levels of glycosylated hemoglobin should be investigated for hemoglobinopathies.
Rev Med Chil 1995 Sep
PMID:[False high levels glycosylated hemoglobin in 2 diabetic patients with persistence of fetal hemoglobin]. 872 37

Fetus-to-fetus transplantation has been suggested for the treatment of hemoglobinopathies in utero. However, dissimilar results have to date been obtained by different groups. We describe a case in which fetus-to-fetus transplantation in HLA-identical twins was performed at the 19th week of gestation by infusion of 0.8 ml of fetal blood from normal to beta-thalassemia affected fetus with the main aim of inducing tolerance. No evidence of engraftment, determined by KM19 polymorphism, was present after 2 years of the procedure. Moreover, an alloreactive cytotoxic T lymphocyte precursor (CTLp) study of affected fetus vs donor and other different stimulators showed that immunization vs tolerance was the real effect of the procedure.
Bone Marrow Transplant 1996 Sep
PMID:Evidence of induced non-tolerance in HLA-identical twins with hemoglobinopathy after in utero fetal transplantation. 887 30


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