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Two experiments were performed to assess viral inactivation during the crosslinking and heat treatment steps of the DCLHb manufacturing process. Stroma free hemoglobin (SFHb) collected from a large scale manufacturing lot was tested in a 1:680 scaled down system in which the key parameters used in the manufacturing process were replicated. In the first study Porcine Parvovirus (PPV), a non-enveloped virus, was used to assess inactivation, while in the second study Bovine Viral Diarrhea Virus (BVDV), an enveloped virus, was utilized. In both experiments, the SFHb solution was deoxygenated and an aliquot of virus suspension was added. To initiate the crosslinking reaction, a solution of bis (3,5-dibromosalicyl) fumarate (DBBF) in HEPES buffer was added to the test solution. In both experiments the reaction times and the degree of crosslinking were normal. After crosslinking, the reaction mixtures were heated to 74 +/- 1 degrees C over 30 minutes, held at 74 +/- 1 degrees C for 90 minutes, and cooled to less than 10 degrees C over 30 minutes. In each experiment the degree of crosslinking of final product was 100% and yield of hemoglobin recovery was normal. Samples were removed prior to crosslinking, after crosslinking and before, during and after heat treatment for determination of virus titer and evaluation of key process parameters. The results from these experiments were consistent with those obtained from the full scale manufacturing process for the deoxygenation, crosslinking and the heat treatment step during the production of DCLHb. The results of virus assays showed that crosslinking has no effect on viruses and their subsequent inactivation by heat treatment.

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Small bowel involvement in rheumatoid arthritis is rare and is caused by vasculitis, which results in ulceration, perforation, and necrosis of the small bowel. The authors present a case of rheumatoid vasculitis associated with a small bowel stricture. The patient had a 3-week history of daily postprandial bloating, abdominal cramping, and vomiting. Barium study demonstrated partial small bowel obstruction. Pathologic examination of a resected segment of the small bowel proved that the stricture was caused by rheumatoid vasculitis. To the authors' knowledge, this is the first reported case of such an association in the radiology literature.

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A method is described for rapidly and accurately localizing microcalcifications in breast biopsy specimens to facilitate processing of appropriate tissue for microscopic examination.

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A 42-year-old woman was found to have intravenous leiomyomatosis of the uterus with extension into the inferior vena cava and right atrium. Intravenous leiomyomatosis is a rare neoplastic disease characterized by invasion of venous channels by a benign smooth muscle tumor arising either from the wall of a vessel or from a uterine myoma. Intracardiac extension is often initially misdiagnosed as a right atrial myxoma and may cause death by mechanical obstruction. The diagnosis of intravenous leiomyomatosis should be considered in young women with cardiac symptoms associated with a right atrial mass who also have a pelvic mass or who have previously undergone hysterectomy because of leiomyoma uteri.

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Avoidance of over- or underheparinization during cardiopulmonary bypass (CPB) is crucial in preventing bleeding or clotting. Currently no completely satisfactory method is available for measuring heparin levels--a method that would be rapid, inexpensive, specific, and reproducible. We combined the use of two devices, a rapid plasma separator and a fluorometric heparin assay system, in an attempt to satisfy these requirements in 15 patients having CPB during cardiac surgical procedures. The first instrument separates plasma from whole blood using a pneumatic filtration principle, while the heparin assay system measures the effect of heparin on thrombin conversion of a synthetic fluorogenic substrate. Accurate plasma heparin levels can be generated in less than five minutes, and the assays are inexpensive and easy to perform. Performing heparin assays at critical intervals during CPB allowed desired heparin levels to be maintained and the protamine dose for heparin neutralization to be reduced to a minimum. In addition, studies for heparin rebound revealed negligible rebound up to six hours postoperatively despite the reduced doses of protamine. There were no hemorrhagic or clotting complications in the series.

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Confident monitoring of heparin during cardiopulmonary bypass and subsequent neutralization by protamine has been hampered by the absence of an accurate, reproducible, rapid, simple, and specific assay for heparin. By using two new instruments in tandem, one of which produced 0.5 ml of plasma in 1 min and one which specifically measures heparin in 3-4 min, heparin levels are available in approximately 5 min. By performing heparin assays at a variety of intervals, it was demonstrated that 76% of patients receiving common doses of heparin during cardiopulmonary bypass may have plasma levels that are potentially too low. Minimum neutralizing doses of protamine may be calculated using the formula: (estimated blood volume + pump prime volume) X (plasma heparin level/100) X 1.1 + 50. These doses were nearly two-thirds of previous doses and were unassociated with increased bleeding, clotting, or clinically significant heparin rebound.

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The STATSEP Plasma Separator (Instrumentation Laboratory, Inc, Lexington, MA), a device for rapidly separating plasma from whole blood, generates plasma at the rate of 0.5 ml/min by filtration rather than centrifugation. When plasma was separated by conventional centrifugation or by the plasma separator, there were no clinically significant differences in concentrations of a variety of important analytes in duplicate specimens. In addition, there were no clinically significant differences in measurements of prothrombin times (PT) and partial thromboplastin times (PTT) on plasmas generated by the 2 techniques. This device, therefore, reduces the analytic time of these frequent coagulation tests by 9 min. The above tests were performed on patients with leukemia and with benign and neoplastic elevations of platelet counts, with no differences seen between plasma specimens separated by either technique. Elevated hematocrits, however, require as much as 2 min to produce 0.5 ml of plasma. Both the machine and disposables are inexpensive and easy to operate.

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The performance of a fluorometric heparin assay system was evaluated. The system indirectly measures heparin by its inhibition of thrombin protease action on a synthetic substrate. Our results confirm that within the range of heparin concentrations recommended by the manufacturer, i.e., 0.1-0.8 units/ml, there is an excellent correlation between expected and observed values. Within-day coefficients of variation range from 1% to 2.6%; the between-day coefficient of variation is 6.5. The accuracy of the assay diminishes under 0.1 units/ml. The assay is not influenced by bilirubin, hemolysis, fibrin split products, or lipemia. Results can be generated in less than 5 min. Possible drawbacks are the wide range of acceptability for the supplied heparin standard, and the frequency of pipetting involved.

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Four patients with herpetic esophagitis were examined. In three of them, the presenting symptom was odynophagia. Early in the course of herpetic esophagitis, shallow round and oval ulcers were seen on barium esophagograms. Later, the ulcers filled with fibrinous exudate, forming nodular plaques that projected into the esophageal lumen. Although these findings are diagnostic of esophagitis, they are not specific for a herpes virus infection. The definitive diagnosis must be established by histologic examination, which demonstrates the cytopathic effect of the herpes virus infection within the squamous epithelium.

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A giant synovial cyst with granulomatous synovitis was removed from the thigh and calf in an 80-year-old woman. The lesion included necrotizing, epitheloid cell granulomata with Langhans' type giant cells. Chest X-ray, tuberculin testing, cultures for Acid Fast bacilli, as well as aerobic, anaerobic and fungal cultures were all negative. The treatment consisted of synovectomy and total knee arthroplasty with an uneventful recovery. A giant calf cyst, usually associated with rheumatoid arthritis, but in this situation, noted in granulomatous synovitis seems not to have been reported previously.

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