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C Robert Valeri

Publications and source records attributed to C Robert Valeri.

34 records · Page 2Linked to original sources
PubMed2005

Freezing human platelets with 6 percent dimethyl sulfoxide with removal of the supernatant solution before freezing and storage at -80 degrees C without postthaw processing.

BACKGROUND: Platelets (PLTs) can be frozen with 6 percent dimethyl sulfoxide (DMSO) at -80 degrees C for up to 2 years. This method has been modified by concentrating the PLTs and removing the supernatant before freezing. STUDY DESIGN AND METHODS: High-yield leukoreduced PLTs stored at 22 degrees C for up to 5 days were divided into three equal volumes: one was frozen with 6 percent DMSO at -80 degrees C, thawed, washed, and resuspended in plasma (old method with DMSO); the second was treated with 6 percent DMSO, concentrated to remove the supernatant DMSO, frozen at -80 degrees C, thawed, and diluted with 0.9 percent NaCl (new method with DMSO); and the third was treated with 0.9 percent NaCl without DMSO, concentrated to remove the supernatant solution, frozen at -80 degrees C, thawed, and diluted with 0.9 percent NaCl (new method without DMSO). RESULTS: Freeze-thaw-wash recovery of PLTs frozen by the old method with DMSO was 74 +/- 2 percent with 5 percent PLT microparticles. Freeze-thaw recovery was 94 +/- 2 percent with 7 percent PLT microparticles (new method with DMSO) and 69 +/- 9 percent with 15 percent PLT microparticles (new method without DMSO). Total DMSO in washed PLTs was 400 and 600 mg in PLTs concentrated before freezing. In vivo recovery of PLTs frozen by the new method with DMSO and transfused into normal volunteers was 30 percent and the life span was 7 days. CONCLUSION: Concentrating PLTs before freezing simplified the procedure by eliminating postthaw washing. PLTs frozen by this method had more PLTs with reduced GPIb and increased annexin V binding than those frozen by the old method.

Blood Banking↗
PubMed2005

The 24-hour posttransfusion survival of baboon red blood cells preserved in citrate phosphate dextrose/ ADSOL (CPD/AS-1) for 49 days.

The purpose of this study was to evaluate the baboon as an animal model for evaluating red blood cell (RBC) preservation by comparing the 24-h posttransfusion survival of baboon RBCs preserved in citrate phosphate dextrose/ADSOL (CPD/AS-1) solution at 4 degrees C for 49 days to that of human RBCs preserved under similar conditions. CPD/AS-1 originally was approved by the Food and Drug Administration for 49-day storage of RBCs, but this period subsequently was reduced to 42 days. Adult male baboons (Papio anubis and P. cynocephalus) were autotransfused with RBCs that had been harvested using CPD and that had been resuspended and stored in AS-1 solution at 4 degrees C for as long as 49 days. The 24-h posttransfusion survival was measured using the 51Cr/125I-albumin method. The 24-h posttransfusion survival (mean +/- standard deviation) was 74% +/- 7% for seven units of CPD/AS-1-treated RBCs stored for 35 days, 65% +/- 15% for 12 units stored for 42 days, and 43% +/- 16% for seven units stored for 49 days. The mean 24-h posttransfusion survival rate for autologous baboon RBCs stored in CPD/AS-1 at 4 degrees C for 35 days (74%) was similar to that for autologous human RBCs stored in a similar manner. Further storage for 42 and 49 days resulted in lower values for baboon RBCs compared with human RBCs.

Adenine↗
PubMed2004

In vitro effects of poly-N-acetyl glucosamine on the activation of platelets in platelet-rich plasma with and without red blood cells.

BACKGROUND: This study was performed to assess the effect of poly-N-acetyl glucosamine fiber slurry on plasma clotting proteins, platelets, and red blood cells in the clotting of the blood. METHODS: Citrate phosphate dextrose whole blood was stored at 22degreesC for 48 hours to prepare platelet-poor plasma, platelet-rich plasma (PRP), and PRP plus red blood cells with hematocrit values of 20%, 35%, and 45% with and without an equal volume of poly-N-acetyl glucosamine fibers (1 mg/mL 0.9% NaCl). RESULTS: Thromboelastogram data show that poly-N-acetyl glucosamine fibers (p-GlcNAc) significantly reduced the R time in platelet-poor plasma, PRP, and PRP supplemented with red blood cells. Poly-N-acetyl glucosamine fibers increased, but not significantly, Annexin V and factor X binding to platelets, platelet microparticles, and red blood cell Annexin V binding. Poly-N-acetyl glucosamine fibers increased the production of thromboxane B2 by PRP. CONCLUSION: Poly-N-acetyl glucosamine slurry activates platelets.

Acetylglucosamine↗
PubMed2004

Effect of thrombopoietin alone and a combination of cytochalasin B and ethylene glycol bis(beta-aminoethyl ether) N,N'-tetraacetic acid-AM on the survival and function of autologous baboon platelets stored at 4 degrees C for as long as 5 days.

BACKGROUND: PLTs stored at 22 degrees C have the potential for bacterial contamination, a problem that could be reduced by 4 degrees C storage. Nevertheless, PLTs stored at 4 degrees C exhibit a significantly reduced life span. This study was performed to determine whether treatment of PLTs with thrombopoietin or cytochalasin B plus ethylene glycol bis(beta-aminoethyl ether) N,N'-tetraacetic acid (EGTA)-AM could prevent exponential loss of PLTs stored at 4 degrees C. STUDY DESIGN AND METHODS: Autologous baboon PLTs were stored at 22 or 4 degrees C. The 4 degrees C stored PLTs were treated with 1.5 ng per mL thrombopoietin, with 1 micro mol per L cytochalasin B, and 80 micromol per L EGTA-AM (cyto-EGTA) or not treated and labeled with (111)In-oxine to study their in vivo recovery and life span. PLT function was assessed by correction of an aspirin-induced prolonged bleeding time. Aggregation responses and morphology were also assessed. RESULTS: PLTs stored at 22 degrees C had normal in vivo recovery and linear survival. PLTs stored at 4 degrees C, whether or not they were treated with thrombopoietin, had normal recovery and exponential survival. Aggregation of cyto-EGTA-treated PLTs was similar for PLTs stored at 4 degrees C and fresh PLTs, but decreased in PLTs stored at 22 degrees C for 5 days. The addition of cyto-EGTA to PLTs before 4 degrees C storage inhibited morphologic changes that occurred in PLTs stored at 22 degrees C and cold-induced PLT clumping, but did not prevent exponential disappearance of the PLTs. CONCLUSION: Addition of thrombopoietin or cyto-chalasin B and EGTA-AM to PLTs before 4 degrees C storage did not prevent exponential loss of PLTs.

Animals↗
PubMed2004

The in vitro quality of red blood cells frozen with 40 percent (wt/vol) glycerol at -80 degrees C for 14 years, deglycerolized with the Haemonetics ACP 215, and stored at 4 degrees C in additive solution-1 or additive solution-3 for up to 3 weeks.

BACKGROUND: Red blood cells (RBCs) frozen with 40 percent (wt/vol) glycerol, stored at -80 degrees C (mean temperature; range, -65 to -90 degrees C) for 14 years, deglycerolized in the Haemonetics automated cell processor (ACP) 215 with the 325-mL disposable bowl, and stored at 4 degrees C in additive solution (AS)-1 or AS-3 for 21 days were evaluated. STUDY DESIGN AND METHODS: A total of 106 units of citrate phosphate dextrose adenine-1 RBCs were frozen with 40 percent (wt/vol) glycerol in the original 800-mL polyvinylchloride plastic bag and stored in corrugated cardboard boxes at -80 degrees C for 14 years. The thawed units were deglycerolized with the ACP 215 with a 325-mL disposable bowl and stored in AS-1 or AS-3 at 4 degrees C for 21 days. RESULTS: The freeze-thaw recovery value was 94 +/- 4 percent (mean +/- SD), the freeze-thaw-wash recovery value was 80 +/- 7 percent, and there was no breakage. Thirty-eight units were processed as 19 pairs. Two units of ABO-matched units were thawed, pooled, divided equally into two units, and deglycerolized. One unit was stored in AS-1 and the other in AS-3 at 4 degrees C for 21 days. Units stored in AS-1 exhibited significantly greater hemolysis than those stored in AS-3. CONCLUSIONS: Acceptable results were achieved when RBCs frozen at -80 degrees C for 14 years were deglycerolized in the ACP 215. Deglycerolized RBCs in AS-1 exhibited significantly higher hemolysis than those in AS-3 after storage at 4 degrees C for 7 to 21 days.

Blood Preservation↗
PubMed2003

Incidence of breakage of human RBCs frozen with 40-percent wt/vol glycerol using two different methods for storage at -80 degrees C.

BACKGROUND: We reported previously that the incidence of breakage was 34.2 percent when human RBCs were frozen with 40-percent wt/vol glycerol in polyolefin plastic bags stored in aluminum containers at -80 degrees C and subjected to transportation. When human RBCs were frozen with 40-percent wt/vol glycerol at -80 degrees C in PVC plastic bags placed in polyester plastic bags and stored in rigid corrugated cardboard boxes, transportation resulted in a 2.4-percent incidence of breakage. The present study was done to confirm this incidence of breakage. STUDY DESIGN AND METHODS: The Meryman- Hornblower freezing method was compared to the Naval Blood Research Laboratory (NBRL) method of freezing for incidence of bag breakage. Human RBCs frozen by the Meryman-Hornblower method with 40-percent wt/vol glycerol with supernatant glycerol and stored in polyolefin plastic bags in aluminum containers at -80 degrees C were stored at the NBRL from 1974 to 2002. With the NBRL method, human RBCs frozen at -80 degrees C without supernatant glycerol in the 800-mL PVC plastic primary bag inside a polyester plastic bag in a rigid corrugated cardboard box were stored at the NBRL from 1984 to 2002. RESULTS: The incidence of breakage for 532 units of RBCs that had been frozen by the Meryman- Hornblower method and stored in aluminum containers was 47.3 percent for nontransported units. RBCs that had been frozen by the NBRL method and stored in rigid corrugated cardboard boxes exhibited breakage of 2.4 percent for 2424 nontransported units and 6.7 percent for 633 transported units. DISCUSSION: The incidence of breakage was significantly lower for RBCs frozen by the NBRL method than for the RBCs frozen by the Meryman-Hornblower method.

Blood Preservation↗
PubMed2003

Effect of WBC reduction and storage temperature on PLTs frozen with 6 percent DMSO for as long as 3 years.

BACKGROUND: PLTs frozen with 6 percent DMSO can be stored at -80 degrees C for 2 years, while those frozen with 5 percent DMSO at -150 degrees C can be stored for at least 3 years. The more rapid deterioration seen in PLTs frozen at -80 degrees C may be due to the presence of granulocytes. The effects of storage temperature and WBC reduction on PLTs frozen with DMSO and the breakage of the PVC plastic bags stored at -80 and -135 degrees C were assessed. STUDY DESIGN AND METHODS: Apheresed PLT-rich plasma (PRP) was either divided into two equal volumes where one volume was WBC-reduced and the other volume was not or filtered or not and then divided into two equal volumes. PLTs frozen with 6 percent DMSO were stored in PVC plastic bags at either -80 or -135 degrees C for as long as 3 years. RESULTS: After 2 years of storage at -80 degrees C, the PLTs exhibited satisfactory freeze-thaw-wash values regardless of whether or not they were WBC-reduced, but after 2 to 3 years of storage at -80 degrees C, the PLTs had significantly reduced freeze-thaw-wash values. Freeze-thaw-wash values were not reduced in PLTs stored at -135 degrees C for up to 3 years. CONCLUSIONS: WBC reduction did not improve freeze-thaw-wash recovery values in PLTs stored at -80 or -135 degrees C for up to 3 years, but reducing the storage temperature from -80 to -135 degrees C did. Breakage of PVC plastic bags stored at -135 degrees C was excessive.

Blood Platelets↗
PubMed2003

Comparison of radioisotope methods and a nonradioisotope method to measure the RBC volume and RBC survival in the baboon.

BACKGROUND: RBC volume, 24-hour posttransfusion survival, and life span can be measured with radio-isotopes and nonradioactive procedures. STUDY DESIGN AND METHODS: RBC volume was measured directly with autologous baboon RBCs labeled with biotin-X-N-hydroxysuccinimide (NHS), 51Cr, 99mTc, and 111In-oxine and indirectly from the 125I plasma volume and the total body Hct. Twenty-four-hour posttransfusion survival and life span were measured in autologous fresh baboon RBCs labeled with 51Cr, 111In-oxine, 99mTc, and biotin-X-NHS. RESULTS: Significantly larger RBC volumes were observed when the fresh autologous RBCs were labeled with 51Cr, 111In-oxine, or 99mTc than when they were labeled with the nonradioactive biotin-X-NHS. Twenty-four-hour posttransfusion survival values were significantly lower in the RBCs labeled with 111In-oxine or 99mTc than in the RBCs labeled with 51Cr. CONCLUSIONS: The greater in vivo elution of 51Cr, 111In-oxine, and 99mTc than that of biotin-X-NHS influenced the measurements of RBC volume, 24-hour posttransfusion survival, and life span of the fresh baboon RBCs.

Animals↗
PubMed2003

Ketone and pyruvate Ringer's solutions decrease pulmonary apoptosis in a rat model of severe hemorrhagic shock and resuscitation.

BACKGROUND: Resuscitation fluids containing beta-hydroxybutyrate (BHB) have been shown to decrease cellular injury after hemorrhagic shock and resuscitation through an unknown mechanism. We tested whether this effect was related to BHB-induced metabolic modulations. METHODS: Male Sprague Dawley rats (n=30) were subjected to volume-controlled hemorrhage (27 mL/kg during 10 minutes followed by 75 minutes of shock during which another 8 mL/kg of blood was withdrawn). Experimental groups included the following: (1) sham, (2) no resuscitation (NR), (3) racemic lactated Ringer's (DL-LR) solution, (4) LR containing L-isomer only (L-LR), (5) ketone Ringer's solution with lactate substituted by BHB (KR), and (6) pyruvate Ringer's solution with lactate substituted by pyruvate (PR). The resuscitation fluids were infused during 45 minutes simultaneously with additional hemorrhage of 8 mL/kg. Hemodynamic and physiologic parameters and the plasma levels of BHB were serially measured. The animals were killed 2 hours after resuscitation, and tissues were frozen instantaneously for cellular adenylate extraction and adenosine triphosphate (ATP) and adenosine diphosphate analysis. Pulmonary apoptosis was studied using Western blotting, immunohistochemistry, and reverse transcriptase-polymerase chain reaction. Expression of enzymes involved in ketogenesis and ketolysis was analyzed by reverse transcriptase-polymerase chain reaction. RESULTS: NR and resuscitation with DL-LR increased the expression of apoptotic markers, whereas resuscitation with KR and PR significantly decreased the expression of apoptotic markers in rat lungs. Resuscitation with KR was followed by a profound increase in plasma BHB levels; however, the expression levels of ketolytic enzymes were essentially unaffected. KR infusion did not induce significant improvements in tissue ATP levels. CONCLUSIONS: Resuscitation with KR and PR protects against pulmonary apoptosis without improving tissue ATP content. Therefore, metabolic modulation is unlikely to be the major mechanism by which BHB exerts its protective effects during reperfusion.

3-Hydroxybutyric Acid↗
PubMed2002

Process for the preparation of pathogen-inactivated RBC concentrates by using PEN110 chemistry: preclinical studies.

BACKGROUND: A pathogen-inactivation process for RBC concentrates is being developed by using PEN110 chemistry (INACTINE, V.I. Technologies). The objective of this study was to characterize the quality of RBCs prepared by using the PEN110 process and to measure the virucidal effect achieved against two viruses. STUDY DESIGN AND METHODS: Virology and RBC studies were conducted with standard RBC units treated with 0.1-percent (vol/vol) PEN110 at 22 degrees C for 6 hours. The quality of PEN110-treated human RBCs was assessed with biochemical and phenotypic variables. The in vivo viability of PEN110-treated RBCs in baboons was studied with the double-label (51)Cr/(125)I method. RESULTS: Decreases in infectious titer by inactivation of greater than a 5 log 50-percent tissue culture infectious doses per mL of bovine viral diarrhea virus (an enveloped RNA virus) and porcine parvovirus (a nonenveloped DNA virus) was observed. RBC hemolysis was less than 1 percent after 42 days of storage, and no changes in RBC antigens were observed. The in vivo viability of PEN110-treated baboon RBCs was unchanged from control. CONCLUSION: The preparation of RBCs by using the PEN110 process achieved a significant viral reduction of two diverse viruses without causing adverse effects to the RBCs. The process appears to be a promising approach, thus justifying further study.

2,3-Diphosphoglycerate↗
PubMed2002

Volume of RBCs, 24- and 48-hour posttransfusion survivals, and the lifespan of (51)Cr and biotin-X-N-hydroxysuccinimide (NHS)-labeled autologous baboon RBCs: effect of the anticoagulant and blood pH on (51)Cr and biotin-X-NHS elution in vivo.

BACKGROUND: The RBC injury that occurs during collection of the first few milliliters of blood into the pH 5.0 ACD (NIH, Formula A) is referred to as the lesion of collection. The RBC injury was evaluated by labeling the ACD RBCs with (51)Cr and measuring the 24-hour posttransfusion survival. The effect of the acidification of ACD blood on the in vivo elution of (51)Cr from the RBC has not been reported. STUDY DESIGN AND METHODS: Baboon blood was collected in heparin and in ACD and CP2D at different ratios of blood to anticoagulant. ACD blood with a pH of 5.7 to 6.9 was labeled with (51)Cr. Heparinized blood with a pH of 7.4 was labeled with biotin-X-N-hydroxysuccinimide (NHS). ACD blood with a pH of 5.9 was labeled with both (51)Cr and biotin-X-NHS. The RBC volumes, 24- and 48-hour posttransfusion survivals, and lifespans (T50) were measured. RESULTS: The RBC volume of ACD blood with a pH ranging from 5.7 to 6.9 was not affected by (51)Cr labeling. (51)Cr-labeled ACD blood with a pH of 6.9 had an RBC volume that was significantly greater than that seen in heparinized blood with a pH of 7.4 labeled with biotin-X-NHS. In vivo elution of (51)Cr from the RBCs prepared from the ACD blood with a pH of 5.7 to 6.9 and in vivo elution of biotin-X-NHS from RBCs prepared from ACD blood with a pH of 5.9 were associated with reductions in 24- and 48-hour posttransfusion survivals and T50. CONCLUSIONS: The anticoagulant and the pH of the medium in which the RBCs were labeled with (51)Cr or biotin-X-NHS affected in vivo elution of the label from the RBCs and may reduce posttransfusion survival values.

Animals↗
PubMed2002

Circulation and hemostatic function of autologous fresh, liquid-preserved, and cryopreserved baboon platelets transfused to correct an aspirin-induced thrombocytopathy.

BACKGROUND: The survival of fresh and preserved platelets has been used primarily to determine their therapeutic effectiveness. The function of the fresh and preserved platelets has been difficult to assess. In stable thrombocytopenic patients, platelet function of fresh and preserved allogeneic platelets is evaluated by the reduction in bleeding time. In this study of healthy male baboons, both the survival and function of autologous fresh, liquid-preserved, and cryopreserved platelets in the correction of an aspirin-induced thrombocytopathy was evaluated. STUDY DESIGN AND METHODS: Five healthy male baboons were studied on eight occasions over a 4-year period. To produce a prolonged bleeding time, the baboon was administered 325 mg of aspirin 18 hours before receiving autologous transfusion. The fresh, liquid-preserved, and previously frozen washed platelets were labeled with (111)In-oxine before autologous transfusion. The autologous, nonaspirinated platelets' ability to reduce the aspirin-induced prolonged bleeding time and increase the shed blood thromboxane B2 level at the template bleeding time site was studied. RESULTS: Platelets stored at 22 degrees C for 48 hours had in vivo recovery values similar to those platelets stored for 18 hours, and they significantly reduced the bleeding time and increased the shed blood thromboxane level after transfusion. Platelets stored at 22 degrees C for 72 hours had in vivo recovery values similar to those platelets stored for 18 hours, but the bleeding time was not corrected after transfusion, although there was a significant increase in the shed blood thromboxane B2 level. The cryopreserved platelets significantly reduced the bleeding time and significantly increased the shed blood thromboxane level after transfusion. Cryopreserved platelets had better in vivo survival and function than the 5-day liquid-stored platelets. CONCLUSIONS: The survival of autologous fresh, liquid-preserved, or cryopreserved platelets did not correlate with their function to reduce an increased bleeding time in baboons treated with aspirin.

Animals↗
PubMed2002

Comparison of the effects of a 50% exchange-transfusion with albumin, hetastarch, and modified hemoglobin solutions.

We compared the hemodynamic effects of replacing 50% of the blood volume of anesthetized rats with an equal volume of five solutions: human serum albumin (HSA), hetastarch, unmodified hemoglobin, diaspirin-crosslinked hemoglobin, and o-raffinose-crosslinked hemgolobin. Control rats were exchange-transfused with their own blood. HSA and hetastarch caused a severe reduction in systemic vascular resistance (SVR), hypotension, and acute renal failure immediately after the exchange-transfusion. Unmodified and diaspirin-crosslinked hemoglobins caused comparable and severe increases in SVR, whereas vasoconstriction induced by o-raffinose-crosslinked hemoglobin was minimal. The increased SVR induced by all hemoglobin solutions resolved over a 2-day period as the hemoglobin was cleared from plasma. Body weight was monitored for 5 days after the exchange transfusion as a measure of the relative long-term efficacy of the exchange solutions tested and increased substantially in control rats (that received blood). Rats that received both crosslinked hemoglobin solutions gained a comparable amount of weight as the control group. By contrast rats that received HSA, hetastarch and unmodified hemoglobin failed to gain weight or lost weight over the same period. In summary: i) HSA and hetastarch are relatively ineffective as resuscitative fluids when administered after the loss of a large volume of blood; ii) diaspirin-crosslinked hemoglobin causes severe vasoconstriction, comparable in intensity to that induced by unmodified hemoglobin; iii) o-raffinose-crosslinked hemoglobin induces minimal vasoconstriction; iv) the vasoactive effects of all hemoglobin solutions are reversible. We conclude, that of all solutions tested, both the short- and long-term effects of an exchange-transfusion with whole blood are most closely reproduced by an exchange with o-raffinose-crosslinked hemoglobin.

Animals↗
PubMedDate not supplied

Hemostatic defect in baboons autotransfused treated plasma to simulate shed blood.

BACKGROUND: Nonwashed shed blood may contain products of clotting and fibrinolytic, and antifibrinolytic substances. This study was done to determine how autotransfusion of nontreated plasma and plasma treated with urokinase with and without aprotinin affected hemostasis in healthy baboons. METHODS: A 500-mL volume of blood was collected from the baboon, a 250-mL volume of plasma was isolated, and the RBCs were reinfused. Three baboons were autotransfused untreated plasma. Four baboons received plasma that had been treated with 3000 IU/mL urokinase at +37 degrees C for 30 minutes. Eight baboons received plasma that had been treated first with urokinase 3000 IU/mL at +37 degrees C for 30 minutes and then with aprotinin (1000 KIU/mL). Bleeding time, fibrinogen degradation products (FDP), D-dimer, and alpha-2 antiplasmin levels were measured. RESULTS: During the 4-hour period following autotransfusion of the urokinase-aprotinin-treated plasma, the levels of D-dimer and FDP were significantly higher and fibrinogen and alpha-2 antiplasmin levels were significantly lower than those levels seen after the autotransfusion of nontreated plasma. FDP and D-dimer levels showed significant positive correlations with prothrombin time (PT) and activated partial thromboplastin time (aPTT). A significant negative correlation was observed between thrombin time (TT) and fibrinogen level. A significant positive correlation was observed between bleeding time and D-dimer level and a significant negative correlation between the bleeding time and the fibrinogen level. CONCLUSIONS: The infusion of a volume of urokinase or urokinase-aprotinin treated autologous plasma equivalent to 15% of the blood volume was not associated with a bleeding diathesis in healthy baboons.

Animals↗