Biomedical subjects

R G Cable

Publications and source records attributed to R G Cable.

42 records · Page 3Linked to original sources

PubMedDate not supplied

Platelet viability following storage for 5 days. Influence of holding whole blood for 8 hours at 20 to 24 degrees C before concentrate preparation.

Regional blood centers frequently need to hold units of whole blood at 20 to 24 degrees C for several hours after phlebotomy so that sufficient platelet concentrates can be prepared to meet the increasing need. We have evaluated the in vivo viability and in vitro properties of platelets that were prepared from whole blood drawn into citrate-phosphate-dextrose-adenine (CPDA-1) either immediately after phlebotomy or after an 8-hour hold at 20 to 24 degrees C. Platelet concentrates were stored for 5 days at 20 to 24 degrees C in polyolefin containers (PL 732, Fenwal) with end-over-end tumbler agitation. The autologous in vivo recovery (mean +/- SD) and one-half disappearance of 51Cr-labeled platelets prepared immediately after phlebotomy were 44.4 +/- 9.4 percent and 4.0 +/- 0.5 days, respectively. Platelets prepared after the delay of 8 hours showed a recovery of 44.5 +/- 8.4 percent and a one-half disappearance of 4.1 +/- 0.4 days. After 5 days of storage, platelet concentrates showed a mean pH of 7.21 +/- 0.20 when prepared immediately after phlebotomy, and of 7.22 +/- 0.15 when prepared after an 8-hour delay. Mean morphology scores were 280 +/- 33 and 302 +/- 27 for platelets from units prepared immediately after phlebotomy or after a holding period of 8 hours, respectively. Platelets underwent synergistic aggregation after 5 days of storage, independent of the length of time that the units of whole blood were held prior to centrifugation. These studies indicate that platelet concentrates prepared from units of whole blood held initially for 8 hours can be stored for 5 days at 20 to 24 degrees C and survive satisfactorily in vivo and retain in vitro characteristics.

Blood Platelets↗

PubMedDate not supplied

Iron supplementation in female blood donors deferred by copper sulfate screening.

Female blood donors with low hematocrit levels detected by copper sulfate screening were selected randomly to receive either 75 mg of iron per day, as ferrous gluconate, or a calcium phosphate placebo. Their ferritin, serum iron, total iron-binding capacity, zinc protoporphyrin, and hemoglobin values, as well as their suitability to donate blood, were determined initially (Visit 1) and at four follow-up visits (Visits 2-5). By the second visit, the serum ferritin and iron values of donors receiving iron supplementation differed significantly from those of donors receiving placebo. By the fifth visit, a less marked but significant increase in hemoglobin had occurred in the iron group, but not in the placebo group. At no time was there a significant difference between the groups' suitability to donate blood, with each group donating at almost half of their visits. The authors conclude that iron supplementation at this dose level in deferred female blood donors improves their iron status and hemoglobin levels, but does not significantly increase their suitability to donate blood as compared with the suitability of placebo-treated donors.

Administration, Oral↗

PubMedDate not supplied

Trends in hepatitis B surface antigen (HBsAg) prevalence in volunteer blood donors in Connecticut, 1973-1983.

A total of 1,573,769 blood donations from volunteer blood donors from Connecticut were tested for Hepatitis B Surface Antigen (HBsAg) from 1973 to 1983. The prevalence of HBsAg decreased over this 10 year period among first time as well as repeat donors. This decrease was much more pronounced in the first three years of the study (1973 to 1975) in repeat donors. Thereafter, prevalence was stable. In first-time donors, the largest decrease also occurred in the first three years. In contrast to repeat donors, however, marked fluctuations in the prevalence were noted in first time donors. As has been the case in previous studies, HBsAg prevalence in first-time donors was significantly higher than that observed in repeat donors. Our study encompasses the longest period of observation in comparison to previous reports on HBsAg prevalence among blood donors. While it has been previously established that a decrease in prevalence over time does occur among repeat donors, stabilization of prevalence after an initial reduction found in our study has not been previously documented. This may indicate an irreducible minimum prevalence rate in the repeat donor population. In addition, our study for the first time convincingly demonstrates a reduction in prevalence in first-time donors which may reflect better communications at the donor recruitment and nursing level.

Blood Donors↗

PubMedDate not supplied

HLA alloimmunization with leukocyte concentrates from HLA-matched and HLA-non-matched donors in patients with Hunter's syndrome.

The incidence and characteristics of HLA alloimmunization following transfusions of leukocyte concentrates as a source of enzyme replacement were determined in male patients with Hunter's syndrome. Five patients were given leukocyte concentrates from HLA matched donors (Group I) and another five patients received leukocyte concentrates from non-HLA matched donors (Group II). No other blood products were transfused in either group. Immune response pattern of HLA alloimmunization measured as the proportion of screening cells manifesting cytotoxicity with patient's sera obtained during the follow-up period was similar in both groups. HLA alloimmunization is seen with transfused leukocyte concentrates from either HLA-matched or non-HLA-matched donors in patients with Hunter's syndrome. There appears to be a trend for an earlier onset of HLA alloimmunization with fewer transfusions when leukocyte concentrates from non-HLA-matched donors are transfused as compared to leukocyte concentrates from HLA-matched donors. Once HLA alloimmunization occurs, immune response patterns appear similar with either leukocyte product.

Adolescent↗

PubMedDate not supplied

Characteristics and natural history of alloimmunization following HLA-matched leukocyte transfusion in Hunter's syndrome.

The characteristics and natural history of alloimmunization to HLA were studied in five patients with Hunter's syndrome receiving long term transfusions of leukocytes collected from human leukocyte antigen (HLA) matched donors. Patients were not given any other blood component transfusions. All patients became alloimmunized at an average interval of eight months following an average of 15 transfusions. All patients developed HLA alloantibodies to transfused cross-reactive HLA antigens. Antibodies to transfused incompatible HLA antigens also developed in all patients. Multispecific HLA antibodies in which specificity determination could not be made were also seen in four patients. In a small number of patients in this study, despite matching for the private HLA specificities, HLA alloimmunization was not prevented. In fact, broad alloimmunization was seen uniformly in our patients.

Adult↗

PubMedDate not supplied

Effect of methods of platelet resuspension on stored platelets.

Platelets are prepared from whole blood by differential centrifugation. Following their isolation as a platelet button, platelets are allowed to rest for a short period in the residual plasma before resuspension. In this study, the feasibility of resuspending platelets without this rest period is studied. A total of 35 platelet concentrates (PC) were prepared from blood collected in CPDA-1 and resuspended by one of the following four methods: (1) no resting period, PC placed on a rotator immediately after preparation, (2) a 1.5 hour rest period and gentle shaking prior to rotation, (3) no rest period and immediate gentle shaking prior to rotation, and (4) a 1.5 hour resting phase and no shaking prior to rotation. Following the previous processing, all platelet concentrates were stored for 72 hours on an elliptical platelet rotator at 20 to 24 degrees C to provide continuous agitation. A number of in vitro tests were used as indicators of platelet viability during storage. These included platelet morphology, pO2, pCO2, pH, osmotic recovery, number of platelets in the concentrate, and platelet volume distribution. Our findings demonstrate that platelets are of similar quality after storage in all of the four groups described. Our studies suggest that the resting phase is unnecessary for platelet preparation. The elimination of the resting phase would allow platelet concentrates to be available sooner and improve cost-effectiveness of platelet preparation.

Blood Platelets↗