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Biomedical subjects

C R Valeri

Publications and source records attributed to C R Valeri.

At least 379 records · Page 21Linked to original sources
PubMedDate not supplied

Ultrastructural alterations and phagocytic function of cryopreserved platelets.

Fresh human platelets and platelets cryopreserved in 4% dimethylsulfoxide were examined ultrastructurally before and after incubation in a suspension of latex particles. Cryopreserved platelets had fewer discoid forms than fresh platelets. The cryopreserved platelets had many sphered platelets containing an increased number of vacuoles; the sphered platelets were more electron-lucent margination and pallor of organelles. Phagocytosis of latex into vacuoles was markedly impaired in the cryopreserved platelets. The morphologic alterations suggested that the freezing, thawing, and washing procedures reduced the functional activity of platelets.

Blood Platelets↗
PubMedDate not supplied

Therapeutic transfusions of previously frozen washed human platelets.

The platelets used in this study were collected by serial centrifugation, and within four hours of collection were frozen with 5% dimethylsulfoxide (DMSO) at an overall rate of 2 to 3 C per minute by storage in a mechanical refrigerator at -80 C. The frozen platelets were stored for four to ten weeks before thawing and washing. After washing, the units were kept at room temperature for six to eight hours before transfusion. The units were pooled, and an average of eight units was given to each of four patients, with a range of three to 14 units per transfusion. In vitro recovery after washing was about 65 per cent and in vivo recovery of the 51chromium labeled (51Cr) platelets was about 35 per cent. The infusion of these previously frozen washed platelets corrected prolonged bleeding times in patients. The homologous platelets were transfused along with other blood products to treat patients with hematologic disorders. The circulation and function of the donor platelets were influenced by compatibility of the platelets, the quality of platelet preservation and the patient's disease state.

ABO Blood-Group System↗
PubMedDate not supplied

Factors that influence the process of 51chromium labeling of human granulocytes isolated from blood by counterflow centrifugation.

The uptake of 51chromium by human granulocytes isolated from blood by counterflow centrifugation is influenced by the composition of the suspension medium, the incubation period, the temperature and the amount of 51chromium used. Counterflow centrifugation-elutriation isolated approximately 98 per cent of the granulocytes from the blood. Acid-citrate-dextrose (ACD) plasma, citrate-phosphate-dextrose (CPD) plasma and heparinized plasma as resuspension media produced similar labeling results, whereas phosphate-buffered saline resulted in three times greater uptake in 51chromium. The greatest uptake of 51chromium (4%) was achieved after incubation of 37 C for one hour in autologous plasma, and granulocyte integrity and metabolic function in vitro were not adversely affected.

Blood Glucose↗
PubMedDate not supplied

Lactic acidemia in baboons after transfusion of red blood cells with improved oxygen transport function and exposure to severe arterial hypoxemia.

Baboons were bled one-third of their blood volume and then transfused with an equivalent volume of compatible donor red blood cells with 160 per cent of normal 2,3-diphosphoglycerate (2,3-DPG) levels and improved capacity to release oxygen to tissue. The mixture of baboon donor-recipient red blood cells in the circulation had a 2,3-DPG level of 130 per cent of normal. After transfusion, the baboon's inspired oxygen was first lowered from 21 to 10 per cent to produce severe arterial hypoxemia with a PO2 tension of less than 40 mm Hg for two hours and then restored to 21 per cent. Lactic acidemia occurred when the alveolar oxygen tension was reduced so as to produce an arterial oxygen tension of less than 40 mm Hg, even though oxygen consumption was maintained. The data suggest that when red blood cells with normal or improved oxygen delivering capacity are transfused to patients, the alveolar oxygen tension should be sufficient to maintain an arterial oxygen tension of greater than 40 mm Hg.

Animals↗
PubMedDate not supplied

Therapeutic effectiveness and safety of outdated human red blood cells rejuvenated to improve oxygen transport function, frozen for about 1.5 years at 80 C, washed, and stored at 4 C for 24 hours prior to rapid infusion.

After storage at 4 C for 20 to 28 days, red blood cells were biochemically modified to improve their oxygen transport function which had deteriorated during liquid storage. The solution used for rejuvenation contained pyruvate, inosine, glucose, phosphate, and adenine (PIGPA Solution B). The rejuvenated red blood cells were frozen with 40% W/V glycerol in a polyolefin plastic bag and were stored in the frozen state for about 1.5 years at -80 C. After thawing and washing the red blood cells were stored at 4 C in a sodium chloride-glucose-phosphate solution for 24 hours before transfusion. A pool of four to ten units was rapidly transfused to each of 14 elderly anemic recipients, 11 of whom had cardiopulmonary insufficiency. Recovery of the red blood cells after the freeze-thaw process was about 97 per cent, and after the freeze-thaw-wash process about 90 per cent. The 24-hour posttransfusion survival values were about 75 per cent, and the long-term survival values were about 85 days depending on the disease state of the recipient. The red blood cells had 1.5 times normal 2.3-DPG levels and a decreased affinity for oxygen at the time of transfusion and were able to delivery oxygen at high oxygen tension immediately after the rapid infusion of pools of from four to ten units through a 40-or 170-micron filter. Plasma hemoglobin levels were consistent with extravascular sequestration of nonviable red blood cells, and uric acid levels were not increased during the immediate 24-hour posttransfusion period.

Aged↗
PubMedDate not supplied

Cryopreservation of human platelets isolated by discontinuous-flow centrifugation using the Haemonetics Model 30 Blood Processor.

Platelets were isolated from normal volunteers by discontinuous-flow centrifugation using the Haemonetics Model 30 Blood Processor. The numerical equivalent of about five single units of platelets collected at each pheresis were frozen together in a -80 C mechanical freezer with a 6% final concentration of dimethylsulfoxide (DMSO) as the cryoprotectant. Platelet freeze-thaw-wash recovery in vitro was about 80 per cent and the platelet recovery value depended upon the method used to enumerate the platelets. The 51Cr survival values in vivo were about 50 per cent less than those in fresh platelets. These values were not significantly different from those seen when platelets were isolated from single units of blood by differential serial centrifugation. Transfusion of two and one-half units of freeze-preserved platelets provided an increase in the recipient's circulating platelet count comparable with that from one unit of fresh platelets. The hemostatic effectiveness of freeze-preserved platelets isolated by discontinuous-flow centrifugation has not yet been studied.

Adult↗
PubMedDate not supplied

Freezing in the primary polyvinylchloride plastic collection bag: a new system for preparing and freezing nonrejuvenated and rejuvenated red blood cells.

Red blood cells were stored at 4 C in the primary bag with an integrally attached empty transfer pack so that the red blood cells could be rejuvenated or not, as desired before glycerolization and freezing. The rejuvenation and glycerol solutions were added through ports in the system. After glycerolization, the red blood cells were concentrated by centrifugation to remove the supernatant glycerol before freezing with 40% w/v glycerol in the primary polyvinylchloride (PVC) plastic container at -80 C. After thawing, the red blood cells were washed using either the Haemonetics Blood Processor 115 or the IBM Blood Processor 2991-1 or 2991-2. In each system, 50 ml of 12% sodium chloride and 1.5 to 1.6 liters of 0.9% sodium chloride-0.2% glucose-25 meq/l disodium phosphate were used. Recovery of red blood cells in vitro was 91 per cent. After three days of postwash storage at 4 C, nonrejuvenated red blood cells had a mean 24-hour posttransfusion survival of 88 per cent, and outdated-rejuvenated red blood cells a value of 81 per cent. This new system is simpler and safer than methods previously used in this laboratory, and red blood cell recovery and 24-hour posttransfusion survivals were comparable or better.

Blood Bactericidal Activity↗
PubMedDate not supplied

A pre-sealed overwrap method of protecting frozen blood components during water immersion thawing.

Forty samples of frozen human plasma were thawed in a 37 C water bath following storage at -80 C for 48 hours. Twenty of these samples were protected by heat-sealed polyethylene overwraps prior to freezing and thawing. The remaining 20 samples were unprotected. None of the protected samples leaked during thawing. The thawing times for the protected overwrap method were prolonged. This method represents a practical procedure for reducing bacterial contamination when blood components are thawed in nonsterile water baths.

Blood Preservation↗
PubMedDate not supplied

Freezing red blood cells prepared for quality control of antiglobulin sera.

A small-aliquot freezing technique was employed to store at -80 C red blood cells (RBC) prepared for quality control of antiglobulin sera. These RBC were used to test the specificity and potency of both polyspecific and monospecific antiglobulin sera on the day of use. Following deglycerolization, about 83 per cent of test RBC were recovered. They were then stored as 5 per cent suspensions in 0.9% NaCl at 4 C for up to two weeks and tested for specific agglutination. EIg (RBC sensitized with immunoglobulins) and EC4 (RBC sensitized with the fourth component of human complement) remained reactive for the two-week period. EC43 (RBC sensitized with both the fourth and third components of human complement) tended to lose reactivity only with anti-C3c antibodies following deglycerolization and storage. EC3d (RBC sensitized with the C3d fragment of the third component of human complement), produced in vivo as a result of Mycoplasma pneumoniae infection, remained reactive for the two-week period, whereas EC3d prepared by the alternative pathway of complement activation was useful only for one week. Use of deglycerolized test RBC improved quality-control procedures by saving materials and technician time as well as by providing a constant supply of uniformly prepared test RBC.

Complement C3↗
PubMedDate not supplied

Enumeration of previously frozen platelets using the Coulter Counter, phase microscopy, and the technicon optical system.

The Coulter Counter, phase microscopy, and the Technicon optical system were used to enumerate platelets in samples of whole blood, platelet-rich plasma, platelet concentrates before and after addition of DMSO, and on platelet concentrates that had been frozen, thawed, and washed. We observed agreement among the three counting methods when platelet counts were determined in whole blood, platelet-rich plasma, and platelet concentrate before and after DMSO addition. Enumeration after the cryopreservation process, however, showed highly significant differences among the counting systems. Platelet counts on platelet concentrates after freezing the thawing performed with the Coulter Counter were 25 per cent greater than with phase microscopy and 55 per cent greater than with Technicon. Counts with phase microscopy were 30 per cent greater than Technicon values. These data indicate that the method used to enumerate previously frozen platelets affects the apparent platelet count.

Cryoprotective Agents↗
PubMedDate not supplied

Cryopreserved red blood cells for pediatric transfusion. Frozen storage of small aliquots in polyvinyl chloride (PVC) plastic bags.

Human nonrejuvenated and rejuvenated red bood cells were prepared for cryopreservation and subsequent pediatric transfusion. Glycerol was added to the red blood cells in the primary polyvinyl chloride plastic collection bag to achieve a concentration of 40 per cent W/V. The red blood cells were concentrated by centrifugation, and the supernatant glycerol was discarded. Each glycerolized unit was divided into four equal aliquots in the individual 600-ml bags of a dry quadruple polyvinyl chloride plastic system, and each aliquot was frozen and stored at -80 C. After thawing, sodium chloride solutions were used to wash the aliquots in the IBM Blood Processor 2991-1 or 2991-2 or the Haemonetics Blood Processor 115, and the washed aliquots were stored in a sodium chloride-glucose-phosphate solution at 4 C for 24 hours. Freeze-thaw recovery of the red blood cells was about 97 per cent, and freeze-thaw-wash recovery was about 84 per cent. Twenty-four-hour posttransfusion survival values were about 92 per cent for both nonrejuvenated and indated-rejuvenated red blood cells. Nonrejuvenated red blood cells, those frozen within three to five days of collection without biochemical modification, had normal oxygen transport function at the time of transfusion; rejuvenated red blood cells, those biochemically treated with PIGPA Solution A after three to five days of storage at 4 C, had improved oxygen transport function at the time of transfusion.

Adenosine Triphosphate↗
PubMedDate not supplied

Circulation and function of human platelets isolated from units of CPDA-1, CPDA-2, and CPDA-3 anticoagulated blood and frozen with DMSO.

Platelet concentrates (PC) were isolated by serial differential centrifugation from units of blood anticoagulated with one of the citrate-phosphate-dextrose-adenine solutions (CPDA-1, CPDA-2, CPDA-2). The platelet concentrates were frozen with six percent dimethylsulfoxide at 2-3 degrees C per minute and stored in a -80 degrees C mechanical freezer in polyvinyl chloride or polyolefin plastic containers. After frozen storage at -80 degrees C for up to three months, the concentrates were thawed at 42 degrees C within 2.5 to 4.0 minutes, washed with autologous plasma, two percent dimethylsulfoxide and 10 percent acid-citrate-dextrose solution, and then resuspended in plasma. The washed platelets were labeled with 51Cr and transfused back to the donor from whom they had been obtained. In vitro recovery from whole blood to platelet concentrate was 70.5 +/- 17 percent (mean +/- one SD). In vitro freeze-thaw-wash recovery determined by phase microscopy was 78.5 +/- 12.8 percent, in vivo 51Cr platelet recovery two hours after transfusion was 41.3 +/- 13.5 percent, and the platelets had a linear lifespan of about eight days. A single unit of previously frozen platelets shortened an aspirin-prolonged bleeding time two and 24 hours after infusion. Results were similar with platelets isolated from all three anticoagulants and stored in both plastics. The results also were comparable to previous findings in this laboratory with platelets isolated from ACD and CPD anticoagulated blood.

Adenine↗
PubMedDate not supplied

Survival of MM red cells during hypothermia in two patients with anti-M.

The in vivo survival of M(M+N-) red cells in two patients with anti-M was studied during hypothermia. The antibodies were IgM, of low titer, and did not react at 30 degrees C. 51Cr survival studies were performed using 2 ml of labeled blood. There was normal circulation of M(M+N-) cells at 37 degrees C and no accelerated loss of these cells at blood temperatures between 16 and 28 degrees C. One patient received 187 ml of MN (M+N +) red cells when the blood temperature was 25 degrees C without evidence of clinical transfusion reactions and without development of positive direct anti-human globulin test. Hypothermia did not adversely affect the immediate survival of M(M+N-) red cells transfused to patients with anti-M antibodies reactive in vitro below 30 degrees C.

Aged↗