Post-transfusion recovery of function of 5-day stored platelet concentrates

Platelets show a rapid reduction in their responsiveness to aggregating agents during storage for transfusion, but little is known about reversal of this defect in vivo after transfusion. In this study, fresh and stored platelets from the same donor (n = 12) were labelled with 111In or 51Cr, respectively, mixed, and simultaneously infused. Blood samples were taken for up to 5 d post-infusion, and the functional behaviour of the labelled platelets ex vivo was measured by retention on glass bead columns, and by whole blood aggregability to ADP, epinephrine and ristocetin. Aggregation was determined by filtering aggregated samples through a column of cotton wool to remove the aggregates, and quantitated as per cent decrease in radioactive counts. The study showed that, although infused radiolabelled 5 d stored platelets had a significantly lower aggregability towards ADP and epinephrine immediately (1 h) after infusion (32% and 29%, respectively, of fresh platelet values), a complete restoration to fresh platelet levels was found 24-72 h post-infusion, with no further change observed over the ensuing 5 d with either fresh or stored labelled platelets. A slightly (6-9%) lower adhesion to both uncoated and collagen-coated beads was found for the stored platelets throughout the 5 d period of study post-infusion. In conclusion, these studies show that, with ex vivo testing, platelets stored for 5 d quickly recovered adhesion and aggregability capabilities similar to that of fresh platelets, suggesting that the functional lesion developed during storage is quickly and completely reversed after infusion.

Paired comparison of platelet concentrates prepared from platelet-rich plasma and buffy coats using a new technique with 111In and 51Cr

Two techniques for the preparation of platelet concentrate (PC), the standard platelet-rich plasma (PRP) and buffy coat (BC) methods, were compared in nine paired studies with regard to platelet harvest, white cell (WBC) contamination, and PC quality after 5 days of 22 degrees C storage. Platelet harvest using the BC method averaged approximately 56 percent of the whole blood level (6.2 x 10(10)/concentrate), which was less than the 76 percent achieved with the PRP-PC method (8.7 x 10(10)/concentrate). An additional 5 units collected into an experimental siphon bag for BC-PC processing showed improved platelet harvest (6.7 x 10(10)/concentrate, or approx. 70% of whole blood). WBCs remaining in the BC-PC averaged 0.19 x 10(8) per unit compared to 3.6 x 10(8) per unit for PRP-PC. Buffy coat processing produced red cell (RBC) units with 50 percent of the WBC contamination of conventionally prepared units (9.8 +/- 6.2 x 10(8)/unit vs. 18.9 +/- 7.1 x 10(8)/unit). The siphon bag further reduced WBC levels in the AS-3 RBC units (6.4 +/- 3.7 x 10(8)/unit). In vitro studies performed on Days 1 and 5 after collection showed no significant differences in platelet metabolic and biologic function or cell integrity. Beta-thromboglobulin and surface glycoprotein levels, indicators of platelet activation and membrane alteration, respectively, did not differ significantly in the PRP-PC and BC-PC; nor was lactate production higher in PRP-PC, despite the substantially higher WBC counts. Autologous in vivo platelet viability determinations were performed by using concurrent transfusion of 111In-labeled freshly drawn platelets and 51Cr-labeled stored platelets.(ABSTRACT TRUNCATED AT 250 WORDS)

Case report: hemolytic anemia produced by tolmetin

Tolmetin, a nonsteroidal anti-inflammatory drug, was found to be the etiologic agent in a case of drug-induced hemolytic anemia. A 35-year-old female who had ingested tolmetin sporadically in the past took two doses that resulted in acute hemolysis. Two days after taking the second dose, she had a hemoglobin of 7.0 g/dL, increased serum lactate dehydrogenase, reticulocytosis, and indirect reacting hyperbilirubinemia. The direct antiglobulin test was weakly positive with anti-IgG and anticomplement reagents. The patient's serum was nonreactive with reagent red cells in the absence of tolmetin, but addition of tolmetin to the serum resulted in strong agglutination of all reagent red cells tested. Serologic evaluation of this patient's serum indicated that tolmetin caused hemolysis by an immune complex mechanism. Hemolysis subsided and anemia improved spontaneously.

An algorithm for angiographic estimation of blood vessel diameter

This study was carried out in an attempt to develop an objective and robust method for measuring changes in the diameters of small blood vessels from X-ray angiographic images. Recognizing potential problems with edge detection methods applied to cylindrical vessels in which the contrast diminishes as the boundary is approached, we have attempted to utilize the X-ray absorbance data across the entire cross section of the vessel. Then, assuming a cylindrical geometry, the absorbance data are fit to the cylindrical absorbance function by use of nonlinear regression analysis. The method was tested and calibrated using glass tubes filled with various concentrations of contrast medium. The diameters of small pulmonary arteries were estimated by applying the method of angiograms obtained from an isolated dog lung lobe. The structure of the residuals obtained after the fitting procedure was analyzed to test the appropriateness of the model for use with images of vessels. The results suggest that this approach will have utility for systematically quantifying vessel dimensions.

Lanthanum inhibits surfactant secretion stimulated by lung distension in newborn rabbits

The effect of lanthanum on lung phospholipid secretion stimulated by lung distension was examined in 29.5-d gestation newborn rabbits. Lung lavage with saline alone produced 608 +/- 109 micrograms phospholipid/lung (mean +/- SEM), whereas lavage with 10(-3) M lanthanum produced only 153 +/- 40 micrograms phospholipid/lung (p less than 0.05), the difference in yield being attributed to inhibited lavage-induced secretion with lanthanum. If this interpretation is correct, then an increased residual tissue surfactant should be found in lanthanum-lavaged lungs. Postlavaged lung was separated into IA, IB, and IC fractions by homogenization and then centrifugation with 0.25 and 0.65 M sucrose. The surfactant IB fraction was 763 +/- 65 micrograms phospholipid/g wet lung for saline-lavaged lungs, but 1002 +/- 90 micrograms phospholipid/g wet lung for lanthanum-lavaged lungs (p less than 0.002). This confirms that decreased secretion with lanthanum was associated with increased residual surfactant in postlavaged lung. It is concluded that lanthanum is a potent inhibitor of surfactant secretion stimulated by lung distension.

Effects of various fixatives and fixation conditions on DNA ploidy analysis. A need for strict internal DNA standards

DNA ploidy and cell cycle analyses are being used with increasing frequency as additional, sometimes independent, biologic prognosticators of various malignancies. For obvious reasons, most of the large studies published are retrospective, using archival paraffin-embedded tissues likely to have been fixed and processed differently. To assess the effect of various fixation conditions on ploidy analyses, the authors performed a comprehensive study in which five contiguous aliquots from 26 tissue samples were fixed in formalin for 8. 24, and 48 hours; B5; and the ethanol-based fixative Omnifix (Omni, Xenetics Biomed Inc., Irvine, CA), respectively. The samples were prepared and stained with the use of Hedley's method; the DNA analyses were done with a Coulter EPICS V flow cytometer (Coulter Electronics, Hialeah, FL); and the resulting histograms were interpreted with Multicycle software (Phoenix Flow Systems, San Diego, CA). Mean channels and coefficients of variation (CVs) of the G0/G1 peaks were compared. Increasing fixation times in formalin produced slight shifting to the left on the G0/G1 peaks with differences up to 13 channels. Omni caused similar but more conspicuous changes, with maximal shifting of 51 channels. B5 created the opposite effect, with right-shifted G0/G1 peaks up to 22 channels. The CVs deteriorated progressively with increasing fixation times in formalin. B5 and Omni fixatives conferred the worse histograms, with 6 and 15 cases, respectively, displaying CVs greater than 8. Such significant differences preclude the use of any other internal standard but adjacent normal tissue that was processed exactly the same as the tumor. The validity of DNA results obtained otherwise should be considered questionable. These findings may explain some of the previously published controversial reports and emphasize the need to use an internal standard and more stringent criteria to define aneuploidy in paraffin-embedded tissue.

Effect of calcium and calcium antagonists on phospholipid secretion induced by lung inflation in newborn rabbits

The effect of calcium and selected calcium antagonists on the lung phospholipid secretion associated with lung distension was examined in newborn rabbits. Lung distension was produced by saline lavage or air inflation in freshly killed pups. Calcium or calcium antagonists were added to the lavage solution. The fractional stimulation of secretion with 1.0 mM calcium was 1.94 +/- 0.28 (p less than 0.01), but ethylene diamine tetraacetic acid (EDTA) did not have the expected inhibitory effect. There was dose-related inhibition of phospholipid secretion induced by the calcium antagonist, lanthanum, the fractional recovery decreasing from 1.0 +/- 0.23 at 10(-5) molar, to 0.43 +/- 0.19 at 0.5 x 10(-4) molar, to 0.22 +/- 0.03 at 10(-4) molar and 0.19 +/- 0.05 at 10(-3) molar (p less than 0.001). This inhibition was significantly reversed by the addition of 10 mM calcium. Although nifedipine and verapamil had no effect, nickel and cadmium also inhibited secretion. Therefore, it is likely that lanthanum acted as a calcium channel blocker, suggesting the importance of extracellular calcium. The observation that intense calcium chelation with ethylene glycol bis-aminoethylether tetraacetic acid-bis-aminophenoxyethane tetraacetic acid (EGTA-BAPTA) had a significant inhibitory effect, supports the conclusion that a superficial calcium pool in the plasma membrane may be an important stimulus for phospholipid secretion during lung distension. The inhibitory effect of neomycin, a drug known to displace superficial calcium, was consistent with this conclusion.

Cryopreserved platelets have decreased adhesive capacity

The technique of freezing blood platelets has proven very useful in transfusion support of some patients who have become alloimmunized by prior transfusions. Although transfused frozen platelets have an acceptable life span in vivo, functional defects have been found when these cells were tested in vitro. The adhesive properties of frozen platelets were investigated by use of a modified Baumgartner chamber to perform paired perfusion studies of fresh versus frozen platelets or fresh versus 5-day-stored platelets from the same whole blood unit. Platelets were either frozen in liquid nitrogen with dimethyl sulfoxide as the cryopreservative or stored under standard blood bank conditions for 5 days. The freeze-thaw recovery of platelets was 73 +/- 8 percent. Frozen platelets exhibited a significant decrease in platelet adhesion as compared to fresh platelets from the same unit; adhesion of frozen platelets was only 53 percent of that of fresh platelets (p = 0.04). A slight, but insignificant decrease was noted with platelets stored for 5 days (86%, p = 0.197). These findings indicate that frozen-thawed platelets have a significant defect in adhesive capacity as compared to fresh platelets, and that platelets stored under blood bank conditions for 5 days maintain adhesive capacity well.

T lymphocyte surface antigen markers in osteoporosis

Two distinct syndromes of osteoporosis have been postulated: type I, which is characterized by accelerated bone loss occurring in women during the early postmenopausal period; and type II, an age-related process of bone loss affecting both men and women in and after the seventh decade. Recently there has been indirect evidence linking local products of the immune system with bone remodeling. We therefore studied peripheral blood profiles of specific lymphocyte phenotypes in women with type I osteoporosis and in older women and men with type II osteoporosis. The ratio of CD4-bearing (T helper) cells to CD8-bearing (T cytotoxic-suppressor) cells (CD4/CD8 ratio) was elevated in women with symptomatic type I disease. In addition there was a significant negative correlation (r = -0.62, P less than 0.001) between the CD4/CD8 ratio and the spinal bone mineral density measured by dual-photon absorptiometry. In contrast, older men with a history of fracture (hip or spine) had CD4/CD8 ratios similar to control men. The number of T cells bearing IL-2R or VLA-1 was not different between osteoporotic subjects and controls in either men or women. This study supports the concept that local products of the immune system may be directly or indirectly involved in the pathogenesis of type I osteoporosis.

Degradation of 2-phosphoglycerate by cytotoxin B of Clostridium difficile

Cytotoxin B of C. difficile was highly purified by selective ammonium sulfate precipitation, Biogel A5m chromatography, phenyl boronate hydrophobic interaction chromatography and ultracentrifugation. The final cytotoxic product had a specific activity of 7.8 X 10(8) units/mg protein and showed a single protein band with an estimated molecular weight of 163,000 when subjected to SDS-PAGE. Immunoelectrophoresis of the final product showed a single precipitin arc. The addition of cytotoxin B to imidazole-HCl buffer (pH 7.4) containing MgSO4, KCl and the substrate 2-phosphoglycerate resulted in the formation of phosphoenolpyruvate as demonstrated by spectrophotometric analysis. Phosphoglycerate conversion was absent when the cytotoxin was heat-inactivated of reacted with specific antitoxin prior to assay.

A new chondrodystrophy mutation in Japanese quail (Coturnix japonica)

A second form of hereditary chondrodystrophy (ch-2) has been discovered in a selected line of Japanese quail, Coturnix japonica. This form of chondrodystrophy is autosomal and recessive, characterized by an overall shortening and bending of the long bones of the wings and legs, slight dwarfing of the trunk, bulging of the eyes, flattening of the head, and a parrot beak. The shortened long bones vary in regard to the amount of bending from nearly straight to bends of up to 90 degrees in the midshaft region. In severe cases, the bend is evident as a protuberance of the skin. Affected embryos usually survive the 18-day incubation period. Several have hatched, but most survived no longer than 4 days after hatching. Only one female has survived long enough to lay eggs. Testcrosses indicated that this mutation is not allelic to micromelia.

Affective disturbance in eating disorders

Thirty-three bulimic and 14 restrictive anorexics were compared on DSM-III diagnoses of affective and anxiety disorders, observer-rated and self-rated measures of depression and anxiety, and family history. A subgroup of 18 eating disorder subjects was administered the dexamethasone suppression test. The same 18 subjects were compared to 13 subjects with affective disorder on the Schedule for Affective Disorders and Schizophrenia. It was found that a large group with bulimia and restrictive anorexia nervosa was subject to a depressive disorder. Thirty-eight percent of the sample fulfilled criteria for a major depressive episode. The dysphoric experience seemed as intense in the bulimic and restricter group. There was a high incidence of dexamethasone nonsuppression (55%), which was found to be related to various measures of depression. Bulimics and restricters differed in their family history of affective disorder. While 61% of bulimics had a positive history of depression, this was found in only 23% of restricters (p less than .03).

Muscle protein synthesis: regulation of a translational inhibitor

Insulin and branched-chain amino acids are known to stimulate protein synthesis in skeletal muscle. Extracts prepared from rat diaphragms after incubation in balanced salt solution and glucose alone yielded heat- and acid-stable, TCA-precipitable, nondialyzable factor(s) that inhibit protein synthesis when added to rabbit reticulocyte lysates. Polyribosomal profiles of inhibited lysates were consistent with a defect in peptide-chain initiation. Addition of insulin and amino acids to the diaphragm incubation media partially removed the inhibition seen with the muscle extract and was accompanied by an increase in polysomes and decreased subunits. Similarly, extracts prepared from rat hindlimb muscle 48 h after induction of diabetes were much more inhibitory in rabbit reticulocyte lysates than extracts from control rats. Polyribosomal profiles were consistent with defective peptide-chain initiation. Trypsin treatment before assay abolished the inhibitory activity of muscle extracts from diabetic rats. Because translation-inhibiting peptide(s) appear to be under metabolic and/or hormonal control, their possible role in muscle protein homeostasis warrants further study.