摘要:

This survey is intended to illustrate some major areas relevant to the diagnosis and treatment of sickle cell syndromes that have benefited by the input of molecular genetic approaches. The development of gene mapping techniques has permitted the direct examination of the effect of co-inheritance of alpha-thalassemia and sickle cell anemia on clinical severity, providing, for the first time, a direct strategy for investigation of the clinical heterogeneity of these syndromes. In addition, antenatal diagnosis of these disorders is now best done by direct gene mapping whenever appropriate facilities are available.Treatment by manipulation of gamma-globin gene expression has been shown to be an effective means of achieving at least partial reversal of the hemoglobin F to hemoglobin A switch. Whether the magnitude of this reversal is sufficient to interfere with the clinical phenotype of sickle cell disease remains to be determined. Moreover, the agent currently available to accomplish this goal, 5-azacytidine, remains unsuitable for widespread clinical application for a variety of reasons. Nonetheless, the molecular geneticist has already demonstrated that desirable effects can be achieved by building on the knowledge of glogin gene physiology. This knowledge is best acquired by application of the concepts and methodologies of molecular genetics.

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

In 1972, Congress passed the National Sickle Cell Disease Control Act which, for the first time, provided authority to establish education, information, screening, testing, counseling, research, and treatment programs. Under the administration of the National Institutes of Health, comprehensive sickle cell research and treatment centers were established and, under the administration of the Health Services Administration, sickle cell screening and education clinics were established.In the following decade (1972–1982), a flurry of activities occurred in all areas relating to sickle cell disease, including research, treatment, development of teaching and educational materials, public awareness campaigns, as well as community participation and community and patient involvement in program development. Major changes took place in legislation, in funding mechanisms for programs, in interaction of the sickle cell disease constituency population with constituency groups devoted to other categorical genetic diseases, and in the emergence of political activism for sickle cell disease programs and patients. The nature of the recent cuts in funding and their effects on sickle cell programs are discussed.

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

The author was a biochemist who, because he had experience in plasma iron estimations, became involved in the investigation of a hypochromic anemia in India during World War II. This led to another such study in Uganda after the war. There, an investigation of the incidence of sickling led to the discovery of overall differences between Hamitic-speaking tribes and the Bantu and Nilotes. A few exceptions could later be explained on the basis of the effect of malaria on sickling incidence. A mapping of the world distribution of sickle-cell and other hemoglobins followed, as well as a search for factors which cause the severity of sickle-cell anemia to vary. A most important lowering influence on this severity seems to be that of a-thalassemia. It is suggested that the high incidence of α-thalassemia type 2 (α/αα) in malarial regions is not related to malaria itself but to the β-chain abnormalities which protect against malaria and therefore are frequent in the same populations. Alpha thalassemia in turn has a selective value because it lowers the pathological effect of sickle-cell anemia, as well as the consequences of Hemoglobin E and β-thalassemia.

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

Our previous studies on the mechanism by which citrate agar electrophoresis separates hemoglobins led to the conclusion that hemoglobins bind to at least some sulfated polysaccharides. In the present report, we describe our deduction at the location of the binding site on the hemoglobin molecule. This led to the prediction, on theoretical grounds, that the anionic polysaccharides should possess anti-gelling actions toward hemoglobins and might be useful drug models. We have shown that anionic polysaccharides including heparin, lambda-car-rageenan, dermatan sulfate, fucoidan, and agaropectin have anti-gelling activity.Evidence indicates that heparin can be introduced into red cells by synthetic lipid vesicles (liposomes) and that, once introduced, acts to block sickling. Because of the high solubility and low toxicity of the polysaccharides, we propose that these compounds deserve further study as potential anti-sickling agents.

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

Bone marrow transplantation is but one of numerous new medical technologies that have raised complex legal and ethical issues. Laws pertaining to medical advances have generally been passed in response to the need to resolve conflicts in judicial opinions rather than in anticipation of those issues which impinge on individual liberties. Bone marrow transplantation law is not an exception. It is, unfortunately, not a product of a planned dialogue between members of those disciplines that could contribute significantly to the development of model codes. Consequently it seems predictable that public policy concerning bone marrow transplantation may not be shaped by the leveling influence that the medical profession can bring to such discussions unless physicians take the initiative to lay the foundations for such dialogues. It is hoped that these discussions will help to enhance and not impede the application of bone marrow transplantation not only for more children but also for other conditions that are not currently treated successfully.

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID

摘要:

Legal issues are always involved in transplantation situations in which the proposed donor is a minor. This paper outlines the legal issues of informed consent and discusses the requirement for courts to be involved in approval of such transplant procedures. The paper provides a description of the legal procedures of which physicians should be aware when they propose to use donors who are minors for transplant operations.

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID

ISSN:0192-8562    

出版商:OVID    

年代:1984

数据来源: OVID