scholarly journals Frequent red cell transfusions reduced vascular endothelial activation and thrombogenicity in children with sickle cell anemia and high stroke risk

2013 ◽  
Vol 89 (1) ◽  
pp. 47-51 ◽  
Author(s):  
Hyacinth I. Hyacinth ◽  
Robert J. Adams ◽  
Jenifer H. Voeks ◽  
Jacqueline M. Hibbert ◽  
Beatrice E. Gee
Author(s):  
Christopher A. Miller ◽  
Bridget Carragher ◽  
William A. McDade ◽  
Robert Josephs

Highly ordered bundles of deoxyhemoglobin S (HbS) fibers, termed fascicles, are intermediates in the high pH crystallization pathway of HbS. These fibers consist of 7 Wishner-Love double strands in a helical configuration. Since each double strand has a polarity, the odd number of double strands in the fiber imparts a net polarity to the structure. HbS crystals have a unit cell containing two double strands, one of each polarity, resulting in a net polarity of zero. Therefore a rearrangement of the double strands must occur to form a non-polar crystal from the polar fibers. To determine the role of fascicles as an intermediate in the crystallization pathway it is important to understand the relative orientation of fibers within fascicles. Furthermore, an understanding of fascicle structure may have implications for the design of potential sickling inhibitors, since it is bundles of fibers which cause the red cell distortion responsible for the vaso-occlusive complications characteristic of sickle cell anemia.


2021 ◽  
pp. 100088
Author(s):  
Christopher Chambliss ◽  
Tatayana Richardson ◽  
John Onyekaba ◽  
Juan Cespedes ◽  
Keri Oxendine Harp ◽  
...  

1978 ◽  
Vol 59 (4) ◽  
pp. 237-245 ◽  
Author(s):  
Eugene F. Roth ◽  
Eliezer H. Rachmilewitz ◽  
Alicia Schifter ◽  
Ronald L. Nagel

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 43-44
Author(s):  
Alyssa M Schlenz ◽  
Shannon Phillips ◽  
Martina Mueller ◽  
Cathy L Melvin ◽  
Robert J Adams ◽  
...  

Introduction: The NHLBI funded Dissemination and Implementation of Stroke Prevention Looking at the Care Environment (DISPLACE) study was designed to improve implementation of stroke prevention guidelines in children with sickle cell anemia (SCA), particularly implementation of transcranial Doppler (TCD) ultrasound for identifying individuals at risk of stroke. The study consists of 3 phases: 1) evaluating current stroke risk screening practices, 2) exploring barriers and facilitators to guideline implementation (needs assessment), and 3) designing and implementing interventions to improve stroke risk screening. A key barrier identified through qualitative methods during the needs assessment was a gap in education, including an overall lack of understanding among patients and caregivers of the purpose of TCD screening. This abstract describes the process of developing one of the interventions for phase 3, a rebranding and educational initiative. Methods: During the needs assessment, 27 key informant interviews and 173 complete surveys were conducted with individuals with SCA and their caregivers. Transcripts from the interviews and survey responses were reviewed to better understand the extent of educational gaps described by families as well as to guide initial rebranding prototypes. Prototypes were developed by the study team, including a new name and logo for TCD as well as an infographic. An interview guide was then created to obtain feedback on the prototypes from individuals with SCA and/or the parent or primary caregiver from two sites in the consortium. Cue cards with prototypes were included with prompts for the "think aloud" method to be applied during interviews. Cue cards were presented first with prototypes for the new name in black font on a white background to solicit feedback on the wording alone. Then, cue cards included various layouts, fonts, and graphics with the prototype names for in-depth feedback on the logo appearance. Finally, participants were asked questions pertaining to the infographic. Results: Twenty interviews were conducted with individuals with SCA and/or the parent/caregiver at two DISPLACE sites. Almost all participants (95%) made the connection between the wording prototypes and TCD without prompting. Many participants expressed that the word "stroke" in both options was "scary," and sometimes chose the option that was "less scary to them." However, many participants also felt that the word "stroke" was necessary to explain the reason for the procedure and would prompt families to ask about the screening as opposed to making them more fearful. The majority of participants (60%) chose "Sickle Stroke Screen" over "Stroke Risk Screen." Participants reported preferring this wording because it is specific to SCA, was easier to remember and represented a less "scary" option. The most commonly preferred logo is presented in Figure 1. Participant reasons for selecting this option were: it is easier to read; they preferred the stacked layout; it is less spread out; they liked the bold letters; it is more eye catching; and it includes the words "sickle cell" in the logo. When asked about preferences for an infographic, the majority described including a picture of a brain. Nearly all participants believed a reassuring message was needed to balance out the fear of the word "stroke." The message, "knowledge is power" provided this balance and resonated with nearly all participants (95%). Figure 2 presents the infographic developed based on participant feedback. Conclusions: Results from this educational rebranding effort highlight the importance of understanding patient and family educational gaps and incorporating their perspective and feedback into educational campaigns. The new logo and infographic were integrated into an educational pamphlet, informative posters and other material designed by the DISPLACE site principal investigators. Part 3 of the study is underway including implementation of the educational initiative at the DISPLACE sites. The new terminology and logo have also been broadly distributed throughout the US through community-based organizations to other patients, families, and stakeholders. Disclosures Kanter: AGIOS: Membership on an entity's Board of Directors or advisory committees; NHLBI Sickle Cell Advisory Board: Membership on an entity's Board of Directors or advisory committees; SCDAA Medical and Research Advisory Board: Membership on an entity's Board of Directors or advisory committees; Wells Fargo: Honoraria; Jeffries: Honoraria; Cowen: Honoraria; bluebird bio, inc: Consultancy, Honoraria; Novartis: Consultancy; Sanofi: Consultancy; Medscape: Honoraria; Guidepoint Global: Honoraria; GLG: Honoraria; BEAM: Membership on an entity's Board of Directors or advisory committees.


1994 ◽  
Vol 45 (4) ◽  
pp. 279-282 ◽  
Author(s):  
Robert J. Adams ◽  
Abdullah Kutlar ◽  
Virgil McKie ◽  
Elizabeth Carl ◽  
Fenwick T. Nichols ◽  
...  

PEDIATRICS ◽  
1971 ◽  
Vol 48 (3) ◽  
pp. 457-458
Author(s):  
Annemarie Sommer ◽  
Stella B. Kontras

The incidence of splenomegaly in sickle cell anemia (defined as a spleen easily palpated below the costal margin in quiet respiration) appears to be around 10% after 10 years of age. Persistent splenomegaly in older children is rare and frequently is associated with hypersplenism. Splenectomy has been the treatment of choice in several reported cases based on red cell survival studies before and after splenectomy.1-3 Removal of the spleen has been found to be associated with marked improvement of previously very shortened red cell survival. We want to report the case of a 12-year-old boy with sickle cell anemia, splenomegaly, and sickle cell heart disease who was treated by radiation therapy for his enlarged spleen because of hypersplenism.


2017 ◽  
Vol 9 (1) ◽  
pp. e2017013 ◽  
Author(s):  
Anil Pathare ◽  
Salam Alkindi

Background: Blood transfusion is an integral part of the supportive care for patients with sickle cell anemia and thalassaemia. The hazard of red cell alloimmunization, however, is one of the main complications of this therapy. Objectives: The aim of this study was to evaluate the incidence of red cell alloimmunization in Omani patients with sickle cell anemia and thalassaemia. Methods: This study included 262 patients whose historical transfusion records were available. One hundred and twenty-nine patients with thalassaemia who were attending the day care unit for regular transfusions, and 133 sickle cell anemia patients admitted at our hospital were included in this study. The Diamed gel system was used for the screening and identification of atypical antibodies. Results: The rate of alloimmunization in sickle cell anemia patients was 31% (n=41), whereas in thalassaemia patients it was 20% (n=26). Antibodies to E, e, C, c, D, K, S, Fyª, Kpª, Jkª and Cw were observed. Among the two groups, 8 developed nonspecific antibodies, and 12 developed more than one antibody; however, 85% of patients were also immunized to Rh and Kell antigens. Conclusions: Red cell transfusions are associated with a significant risk of alloimmunization. It is, therefore, imperative to perform an initial extended red cell phenotyping for both donors and recipients, and carefully select ABO, Rh and Kell matched donors.


Blood ◽  
1982 ◽  
Vol 60 (6) ◽  
pp. 1332-1336 ◽  
Author(s):  
MG Luthra ◽  
DA Sears

Abstract To determine whether diminished activity of the Ca++ extrusion pump could account for the high levels of red blood cell (RBC) Ca++ in sickle cell anemia (SS), we measured calmodulin-sensitive Ca++ ATPase activity in normal and SS RBC. Hemolysates prepared with saponin were compared, since such preparations expressed maximum ATPase activities, exceeding isolated membranes or reconstituted systems of membranes plus cytosol, SS RBC hemolysates had greater Ca++ ATPase activity than normal hemolysates; they exhibited higher Mg++ and Na+ + K+ ATPase activities as well. Assays on density (age) fractions of SS and normal red cells demonstrated that all ATPase activities were highest in low density (young) cells, and activities in SS red cells exceeded those in normals in all fractions studied. Thus, when studied under conditions that maximize enzyme activity, Ca++ ATPase activity, like Mg++ and Na+ + K+ ATPase, is actually increased in SS RBC, probably due to the young red cell population present. The elevated Ca++ levels in these cells are more likely due to an increased Ca++ leak or abnormal calcium binding than to defective extrusion by the ATPase pump.


Blood ◽  
2003 ◽  
Vol 101 (6) ◽  
pp. 2401-2404 ◽  
Author(s):  
M. C. Driscoll

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