Observations on the Chromium Labelling of ACD-Stored and Previously Frozen Red Cells

Chromium labelling characteristics of both ACD-stored and previously frozen red cells were evaluated. The chromium uptake of previously frozen red cells processed by agglomeration was inversely related to the hemoglobin level of the suspending fluid. Ascorbic acid was not needed for the labelling of previously frozen, agglomerated red cells.
Cellular injury, as measured by increase in supernatant hemoglobin during post-thaw storage at 4 C, occurred with the agglomerated, previously frozen red cells when: (1) Na₂ EDTA was present in the glycerolizing solution; (2) the disaggregation of the agglomerated red cell mass was carried out with 75 rather than 250 ml of isotonic saline; and (3) the storage temperature of the glycerolized red cells was interrupted for one week with a storage interim at either 4 C or −20 C.
By use of a phthalate ester technic, red cells were separated into three fractions on the basis of cellular density. Preferential chromium labelling of red cells was noted: the lightest fraction contained significantly more radioactivity than the heaviest fraction.     

Hypotonic duodenoscopy

Inducing duodenal hypotonia by the intravenous injection of propantheline bromide is a simple, safe procedure that will permit this organ to be visualized adequately by endoscopy. Twenty-five consecutive patients with suspected duodenal pathology received an intravenous injection of propantheline at the time the pylorus was being viewed through the endoscope. Immediately after the injection, the pylorus dilated and the endoscope was passed easily into the duodenal bulb, where good visualization was achieved. A small bulb syringe attached to the air channel of the endoscope and gentle insufflation of air permitted good visualization of the second portion of duodenum. While the propantheline method is not necessary in all patients undergoing duodenoscopy, those in whom it is difficult to pass the endoscope through the pylorus or in whom antroduodenal motility precludes adequate examination, injection of the antispasmodic provides one easy, safe method for examining the duodenum by duodenoscopy.     

Regeneration of gastric mucosa after aspirin-induced injury in the rat

Regeneration of gastric mucosa damaged by aspirin was studied in 6-week-old rats, using histologic and autoradiographic technics. Aspirin (120 mg/kg) was given by esophageal intubation either in a single dose or each day for 14 days. After a single dose, two types of lesion were observed in the mucosa of the body of the stomach: (a) superficial erosions which were already present after 30 minutes and which completely healed within 24 hours; (b) deeper erosions, reaching maximal numbers at 4 hours, which healed slowly with a median disappearance time of 5 days and which were associated with a focal increase in³H-thymidine-labeled cells. The peak increase in labeling occurred between 16 and 48 hours. The pattern and rate of healing was not altered by repeated daily aspirin. The investigation has demonstrated slow healing of deep mucosal erosions caused by aspirin; the slow healing can be explained by destruction of the progenitor zone by the initial injury.Supported by the National Health and Medical Research Council and the Alfred Hospital.Presented in part to the Australian Society for Medical Research, December 1971.     

Acute colitis and bacteremia due toCampylobacter fetus

An acute febrile illness with dysentery and colitis developed in a 26-year-old man following a wilderness outing. Campylobacter fetus ssp. jejuni was subsequently grown on blood cultures drawn during the acute illness and 9 days later when the patient was asymptomatic. Proctosigmoidoscopic and histopathologic evidence of acute colitis was present on admission and resolved on follow-up examination. Campylobacter fetus spp. jejuni infection should be considered in the etiology of acute infectious colitis.     

Amebic Liver Abscess

We present a patient with an acute amebic liver abscess with nonreactive serologic tests. Motile hematophagous trophozoites of Entamoeba histolytica were seen microscopically in scrapings from the wall of the abscess. Postoperative serologies revealed rapidly rising then falling titers by SAFA and IHA antibody assays. Serologic tests for amebiasis may be reative in greater than 95% of patients with invasive amebiasis. Nevertheless, a reactive serologic test should not be relied upon exclusively to establish the diagnosis. Sequential serologic testing and surgical intervention to obtain material for microscopic examination, gram stain and bacteriologic culture are warranted in patients with hepatic abscess and nonreactive serologic tests for antibodies to E. histolytica.     

Prevention of HLA immunization with leukocyte-poor packed red cells and platelet concentrates obtained by filtration

HLA immunization is a common complication of transfusion therapy in 30% to 60% of oncohematologic patients. Evidence shows that leukocytes present in cellular blood products are the main component involved in the occurrence of HLA immunization, and several studies showed that leukocyte-poor blood products are less able to induce it. However, leukocyte-poor platelet concentrates obtained by conventional techniques, ie, centrifugation, frequently have a high level of remaining leukocytes. Cotton wool filter Imugard IG 500 can be used to obtain leukocyte-poor cellular blood products. The technique is easy to perform, even in an emergency, and can be used with either packed RBCs or platelet concentrates. Means of 97%, 92%, and 76% elimination of leukocytes are obtained for packed RBCs, pooled standard platelet concentrates, and single-donor platelet concentrates, respectively. Patients were randomized to receive either standard (control group) or filtered (leukocyte-poor group) blood products. Of 112 randomized patients, 69 were evaluable, 35 in the control group and 34 in the leukocyte-poor group. Both groups are comparable according to age, diagnosis, sex ratio, previous transfusions, and pregnancies. There is a significant difference in regard to the HLA immunization rate (31.4% in the control v 11.7% in the leukocyte-poor group, P less than .05) and frequency of refractoriness to platelet transfusions (46.6% v 11.7%, P less than .05). We conclude that this filtration technique can be an efficient means to reduce the HLA immunization rate in polytransfused oncohematologic patients.     

Comparison of stationary vs ambulatory 24-hour pH monitoring recording systems

Twenty-four-hour pH monitoring of the esophagus is frequently performed to assess gastroesophageal reflux. We performed a prospective study to determine if results obtained from stationary and ambulatory pH recording systems are comparable. Two groups of patients were studied. Group I consisted of 12 patients monitored simultaneously by both a stationary and an ambulatory pH recording system, each system having a separate pH and reference electrode. In group II, in order to eliminate electrode variability, 10 patients were monitored simultaneously with both systems and a common single pH and reference electrode. In group I, significant correlations were found in six reflux parameters measured and in the 24-hr composite score (r0.8722). However, in three of the 12 patients, marked discrepancies were noted in the composite score calculated by the stationary and ambulatory recording systems. Small variations in the pH level recorded by different pH electrodes may have accounted for the discrepancies. In group II, where electrode variability was eliminated, a better correlation was noted between all parameters measured (r 0.991), and no discrepancies were noted between calculated composite scores. We concluded that the stationary and ambulatory recording systems tested are comparable in measuring 24-hr esophageal pH.This protocol (WR-1477) was approved by the WRAMC Human Use Committee/Institutional Review Board and supported by Department of Clinical Investigation Funding.The opinions and assertions contained herein are the private ones of the authors and are not to be construed as official policy or reflecting the views of the Department of the Army or the Department of Defense.     

Increased adhesion of erythrocytes to components of the extracellular matrix: isolation and characterization of a red blood cell lipid that binds thrombospondin and laminin

Red blood cell (RBC) adhesion to the vascular endothelium is increased in several pathologic conditions, including sickle cell disease and malaria. However, RBC interactions with components of the subendothelial matrix are not well-characterized. Under in vitro flow conditions of 1 dyne/cm2, washed RBCs bound to the purified adhesive molecules thrombospondin (TSP) and laminin. Sickle RBCs had the greatest adhesion of all tested RBCs. The adhesion of sickle RBCs to immobilized TSP was inhibited by the anionic polysaccharides high molecular weight (MW) dextran sulfate and chondroitin sulfate A, but not other anionic polysaccharides of similar structure and/or charge density. These data were consistent with the RBC adhesive molecule being a sulfated glycolipid. Therefore, TSP-binding lipids from normal and sickle RBCs were isolated and characterized. The TSP-binding lipid was purified by alkaline methanolysis, anion exchange chromatography and preparative thin layer chromatography (TLC). A homogeneous band on TLC was identified using a specific overlay TSP-binding assay. TSP binding to the purified lipid was stable to bass and neuraminidase treatment, labile to acid treatment, and was inhibited by high MW dextran sulfate, similar to that seen with intact RBCs binding to immobilized TSP under conditions of flow. In addition, soluble laminin bound to the purified RBC lipid. This acidic TSP- and laminin-binding lipid(s) isolated from both sickle and normal RBC membranes may contribute to erythrocyte interactions with the subendothelial matrix, hereby participating in the pathogenesis of vaso-occlusive diseases.     

Bilirubin cycles enterohepatically after ileal resection in the rat

BACKGROUND & AIMS: Patients with ileal disease, resection, or bypass are at increased risk of developing pigment gallstones, but the pathophysiological mechanisms are unknown. The aim of this study was to test the hypothesis that ileectomy induces enterohepatic cycling of bilirubin. METHODS: Ileectomy or sham operation was performed in adult male Sprague-Dawley rats with the following control procedures: no operation, ileal transection, proximal or distal jejunectomy, ileocolonic transposition, and ileocecectomy. Bilirubin and bile salt secretion rates were measured after bile duct cannulation performed 3- 11 days after intestinal surgery. Also measured were bilirubin and bile salt concentrations in the colon as well as indices of hemolysis in blood. RESULTS: Compared with controls, bilirubin secretion rates were increased significantly 3-5 days after ileectomy, distal jejunectomy, ileocolonic transposition, and ileocecectomy, with no hemolysis occurring. Bile salt secretion rates also increased significantly after ileectomy but decreased markedly with prevention of coprophagy, whereas bilirubin secretion rates remained elevated. By 8-11 days after surgery, intestinal adaptation normalized bile salt reabsorption, and hypersecretion of bilirubin was abolished. Colonic levels of unconjugated bilirubin and bile salts were increased fivefold and eightfold respectively in ileectomized animals, but unconjugated bilirubin levels remained normal in bile. CONCLUSIONS: These results are consistent with the hypothesis that enterohepatic cycling of bilirubin occurs with bile salt malabsorption. (Gastroenterology 1996 Jun;110(6):1945-57)