George H. Goldsmith

The activation of plasminogen by Hageman factor (Factor XII) and Hageman factor fragments.

Activation of plasminogen through surface-mediated reactions is well recognized. In the presence of kaolin, purified Hageman factor (Factor XII) changed plasminogen to plasmin, as assayed upon a synthetic amide substrate and by fibrinolysis. Kinetic studies suggested an enzymatic action of Hageman factor upon its substrate, plasminogen. Hageman factor fragments, at a protein concentration equivalent to whole Hageman factor, activated plasminogen to a lesser extent. These protein preparations were not contaminated with other agents implicated in surface-mediated fibrinolysis. Diisopropyl fluorophosphate treatment of plasminogen did not inhibit its activation by Hageman factor. These studies indicate that Hageman factor has a hitherto unsuspected function, the direct activation of plasminogen.

Primary Pulmonary Hypertension in Patients with Classic Hemophilia

Five patients with classic hemophilia were found to have primary pulmonary hypertension, a disorder not previously recognized in this population. All patients had had their coagulation disorder treated for 10 years or more with self-administered lyophilized concentrates of factor VIII, and all had antibodies to human immunodeficiency virus (HIV). Primary pulmonary hypertension was confirmed by histologic means at autopsy in one patient and by lung biopsy findings in another. In the other three patients, the findings are in agreement with this diagnosis. No patient had underlying cardiac or pulmonary disease, or clinical or pathologic evidence of collagen-vascular disease, vasculitis, parasitic disorders, hemoglobinopathy, or exposure to anorexigenic agents. Whether the primary pulmonary hypertension was related to treatment with lyophilized factor VIII, or to the presence of antibodies to HIV, or both, is unknown.

Activation of protein mediators of inflammation and evidence for endotoxemia in Borrelia recurrentis infection

Fifteen patients with Borrelia recurrentis infection were studied to evaluate the role of certain plasma proteins and endotoxin in the pathophysiology of both the acute illness and the Jarisch-Herxheimer-like reaction. The causative spirochetes disappeared from the blood during the Jarisch-Herxheimer-like reaction, which occurred about 2 hours after antibiotic therapy. The mean titers of Hageman factor, plasma prekallikrein and serum hemolytic complement activity were decreased at the time of admission and 2 hours after treatment, and rose to normal values during convalescence. Serum properdin titers were decreased in 14 patients at the time of admission, in 12 patients 2 hours after treatment, and in none during convalescence. The frequency of elevated levels of fibrinogen-related antigens increased from three patients at the time of admission to 12 patients 2 hours after treatment. Results of plasma limulus tests for endotoxin-like material were positive in 11 patients at the time of admission and in 13 patients 2 hours after treatment. These findings demonstrated that Hageman factor, prekallikrein and proteins of the complement system are activated in B. recurrentis infection and that endotoxin may play a role in both the acute illness and in the development of the Jarisch-Herxheimer-like reaction after treatment.

Neutrophil adhesion in the elderly : inhibitory effects of plasma from elderly patients

Neutrophil (PMN) adherence is a critical component of host defense against infection. We questioned whether abnormalities of PMN adherence may be responsible, in part, for the increased susceptibility to infection in the elderly. We examined the adherence of 51Cr-labeled PMN from 18 elderly (65-95 years) and 18 younger subjects (18-40 years) to gelatin-coated plastic (gel) and bovine aortic endothelial monolayers (BAEC). There was no difference in unstimulated or baseline adherence of elderly or control PMN to either gel or BAEC substrates. N-Formyl-methionyleucylphenylalanine (FMLP), phorbol myristate acetate (PMA), and calcium ionophore A23187 (CI) significantly increased adherence of elderly PMN to gel and BAEC by 204 and 140% for FMLP, 271 and 263% for PMA, and 211 and 150% for CI, respectively. No differences were observed in the increment in stimulated adherence between young and elderly PMN. In contrast, in 5 of 18 subjects, incubation of elderly or young PMN with 10% elderly plasma resulted in greater than 25% inhibition in baseline adherence to BAEC compared to their sex-matched controls. The effect of elderly plasma was specific for BAEC and not seen with the gel substrate and was also demonstrated using human venous endothelium. When the adherence assay was repeated with varying ratios of elderly and young plasma, PMN adherence to BAEC correlated inversely with the proportion of elderly plasma in the assay. With greater than 70% elderly plasma, adherence was depressed below that observed in the absence of plasma. These data suggest the presence of a factor(s) in elderly plasma which may diminish adherence to endothelium. This factor(s) may be important in the increased risk of infection in a segment of the elderly population.

Phase I study of paclitaxel and day 1/day 8 gemcitabine in patients with solid malignancies

A phase I study was designed to evaluate the toxicity of escalating doses of gemcitabine along with fixed-dose paclitaxel in patients heavily pretreated with chemotherapy or radiotherapy. All patients had no prior therapy with the study drugs and possessed both adequate performance and end organ function. Eighteen patients were entered in the study. Characteristics included a median age of 66 years (range, 41 to 77) and stage IV disease in all patients; there were six patients with colon cancer, two with bladder cancer, three with non-small-cell lung cancer, two with esophageal cancer, three with pancreatic cancer, and two with cancer of unknown primary. Paclitaxel (150 mg/m2 over 3 hours) was given on day 1 and gemcitabine (800, 900, and 1,000 mg/m2 over 15 minutes) was given in three separate dose-escalating cohorts (1-3) on days 1 and 8. The treatment cycled every 21 days. The dose-limiting toxicity (DLT) proved to be neutropenia. All nonhematologic toxicities were mild and included gastrointestinal (nausea, vomiting, and diarrhea), dermatologic (rash), and neurologic (paresthesias) disturbances along with transient elevations of liver function tests. The combination of gemcitabine and paclitaxel seems to be well tolerated, and the recommended starting dose for a phase II study, in pretreated patients using a day 1/day 8 treatment schedule, should be 900 mg/m2 for gemcitabine (days 1 and 8) along with 150 mg/m2 for paclitaxel (day 1).

Uric acid nephrolithiasis and acute renal failure secondary to streptozotocin nephrotoxicity

Uric acid nephrolithiasis developed in a 75-year-old man who had received a large cumulative dose of streptozotocin for treatment of metastatic islet cell carcinoma of the pancreas. Oligoanuric renal failure mediated by massive intraureteral uric acid deposits occurred despite normal serum concentrations of uric acid. This case implicates the uricosuric effects of streptozotocin in the pathogenesis of uric acid nephropathy and suggests that renal uric acid excretion should be monitored routinely in patients receiving large cumulative doses of this drug.

Bovine aortic endothelial cells elaborate an inhibitor of the generation of lipopolysaccharide-stimulated human blood monocyte procoagulant activity.

We examined the effect of bovine aortic endothelial cell culture supernatants upon the generation of procoagulant activity by human blood monocytes. Confluent endothelial monolayers were cultured for up to 96 h. At timed intervals, culture supernatants were collected and incubated for 5 h with lipopolysaccharide-stimulated human peripheral blood mononuclear cells. The procoagulant activity of mononuclear cell lysates was determined in a one-stage clotting assay. In five experiments, procoagulant activity with culture supernatant (time 0) was 2,294 +/- 761 U/ml (mean +/- SEM). Culture supernatants from endothelial cells incubated for 24-96 h strongly inhibited mononuclear cell generation of procoagulant activity. Indomethacin (10 microM) added to endothelial cells delayed the appearance of procoagulant inhibitor for 72 h. Bovine aortic smooth muscle cell culture supernatants did not inhibit procoagulant activity. The inhibitor was heat stable, effective at 1:50 dilution, soluble, and acid sensitive, with a molecular weight of less than 1,500. Further studies on subpopulations of mononuclear cells demonstrated that endothelial inhibitor selectively decreased the generation of monocyte procoagulant activity and interfered with T lymphocyte amplification of monocyte production of procoagulant activity. Thus, we have demonstrated that endothelial cells elaborate a potent inhibitor of monocyte procoagulant activity.

Cefepime versus ticarcillin and clavulanate potassium and aztreonam for febrile neutropenia therapy in high-dose chemotherapy patients

An open labeled randomized trial comparing the efficacy and cost of empirically applied cefepime (C) as monotherapy versus combination therapy consisting of ticarcillin and clavulanate potassium and aztreonam (T/A) was performed in febrile neutropenic patients following high-dose chemotherapy (HDC) ± radiation, with or without peripheral blood stem cell support. Over a 28-month period, 126 patients were screened and included in the study. Using afebrile status following 3 days of therapy as a primary endpoint, both regimens produced comparable clinical response rates (C = 55% vs. T/A = 61%). Also, the use of vancomycin for resistant gram-positive infections and alteration of gram-negative infection coverage was similar in both groups (C = 40% vs. T/A = 47% and C = 29% vs. T/A = 24%). Both treatment groups had similar needs for empirical antifungal therapy (C = 25% vs. T/A = 22%). There was a postrandomization difference between the two groups in that the “C” group had a significantly higher number of allogeneic transplants and non–stem-cell-supported patients, whereas the “T/A” group had a significantly greater number of autologous peripheral blood stem cell patients (p < 0.0001). Despite this difference, the C group had a significantly lower cost ratio than the T/A group (p = 0.016). In conclusion, we have shown that C treatment of febrile neutropenic patients following HDC results in similar efficacy and lower cost when compared to T/A, despite the inclusion of higher risk patients in the C group.

Studies on the Blood Clotting and Fibrinolytic System in the Plasma from a Sei (Baleen) Whale

Summary Blood clotting and fibrinolytic systems were studied in the plasma of a sei whale (Balaenoptera borealis). The sei whale belongs to the suborder baleen whales of the order Cetacea. Whale plasma had a greatly prolonged kaolin-activated partial thromboplastin time and was deficient in Hageman factor (factor XII), Fletcher factor (a plasma prekallikrein), and PTA (factor XI). All other clotting factor activities were present in amounts comparable to that of normal human plasma. Whale plasminogen was activated by human urokinase, but not by streptokinase. Whale plasma contained inhibitory activities against thrombin, activated Stuart factor, activated PTA, activated Fletcher factor, and plasmin. We are grateful to Dr. James Mead of the Smithsonian Institution, Washington, D. C., who imported the whale plasma. Ms. Ellen Strecker and Miss Marilyn Burke provided invaluable technical help.

Platelets and Surface‐Mediated Clotting Activity

Summary. In contrast to previously reported studies, no evidence could be adduced for the activation of Hageman factor (factor XII) by platelets, whether or not these cells had been incubated with adenosine diphosphate (ADP).