Psychological Experience of Children and Adolescents with Homozygous Sickle Cell Disease in Brazzaville

SummaryIt has recently been proved that, in vitro, red blood cells (RBCs) from patients with homozygous β-thalassemia behave as procoagulant cells. The procoagulant activity of β-thalassemia RBCs might be the result of an increased exposure of procoagulant phospholipids (i. e. phosphatidylserine) in the outer leaflet of the membrane. In order to test this hypothesis, we compared the catalytic properties of RBCs of patients with β-thalassemia and homozygous sickle cell disease (SS-RBCs) with that of controls. The catalytic parameters (Km, kcat) of prothrombin activation by factor Xa were determined both in the absence and in the presence of RBCs. The turn-over number (kcat) of the reaction was not modified by normal, SS- or (3-thalassemia RBCs. The Km was lower in the presence of normal RBCs (mean value: 9.1 µM) than in the absence of cells (26 µM). The Km measured in the presence of either SS-RBCs (mean value: 1.6 µM) or β-thalassemia RBCs (mean value: 1.5 pM) was significantly lower compared to normal RBCs (p <0.001). No significant difference was observed between SS-RBCs and p-thalassemia RBCs. Annexin V, a protein with high affinity and specificity for anionic phospholipids, inhibited the procoagulant activity of both SS-RBCs and (3-thalassemia RBCs, in a dose-dependent manner. More than 95% inhibition was achieved at nanomolar concentrations of annexin V. These results indicate that the procoagulant activity of both β-thalassemia RBCs and SS-RBCs may be fully ascribed to an abnormal exposure of phosphatidylserine at the outer surface of the red cells.

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Comprehensive Handbook of Childhood Cancer and Sickle Cell Disease

10.1093/oso/9780195169850.001.0001 ◽

2006 ◽

Keyword(s):

Quality Of Life ◽

Sickle Cell Disease ◽

Childhood Cancer ◽

Children And Adolescents ◽

Peer Relationships ◽

Sickle Cell ◽

Cell Disease ◽

Life Issues ◽

Art Research

Over recent decades, tremendous advances in the prevention, medical treatment, and quality of life issues in children and adolescents surviving cancer have spawned a host of research on pediatric psychosocial oncology. This important volume fulfills the clear need for an up-to-date, comprehensive handbook for practitioners that delineates the most recent research in the field--the first of its kind in over a decade. Over 60 renowned authors have been assembled to provide a thorough presentation of the state-of-the art research and literature, with topics including: -Neuropsychological effects of chemotherapy and radiation therapy -Bone marrow transplantation -Important issues about quality of life during and following treatment -Collaborative research among child-focused psychologists -Standards of psychological care for children and adolescents -Stress and coping in the pediatric cancer experience -The role of family and peer relationships The Comprehensive Handbook of Childhood Cancer and Sickle Cell Disease represents both multidisciplinary and international efforts, an alliance between physicians and parents, and a combination of research and service. With a wealth of information of great interest to patients and their families, this volume will also be a welcome resource to the psychologists, psychiatrists, pediatricians, oncologists, nurses, and social workers who confront these issues as they help children and their families through the treatment, recovery, and grieving processes.

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