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2.
J Clin Invest ; 72(6): 2041-9, 1983 Dec.
Article in English | MEDLINE | ID: mdl-6196377

ABSTRACT

The regulation of human Factor Xa was studied in vitro in human and mouse plasma, and in vivo in mouse. In human plasma, 125I-Factor Xa bound to alpha 1-proteinase inhibitor, antithrombin III, and alpha 2-macroglobulin in a ratio of 4.9:1.9:1 as determined by gel electrophoresis and by adsorption to IgG-(antiproteinase inhibitor)-Sepharose beads. The distribution of Factor Xa in mouse plasma was similar. The clearance of Factor Xa in mice was rapid (50% clearance in 3 min) and biphasic. alpha 1-Proteinase inhibitor-trypsin, even at a 2,000-fold molar excess, failed to inhibit the clearance of Factor Xa, while alpha 2-macroglobulin-trypsin inhibited only the later phase of clearance. The plasma clearance of diisopropylphosphoryl-Factor Xa was more rapid than native Factor Xa (50% clearance in 2.5 min), and the clearance was blocked by diisopropylphosphoryl-thrombin. Electrophoresis experiments confirmed that by 2 min after injection into the murine circulation, 90% of the bound Factor Xa was on alpha 2-macroglobulin, in marked contrast to the in vitro results. Organ distribution studies at 3 and 15 min with 125I-Factor Xa demonstrated that the majority of radioactivity was in the liver, with significant radioactivity also present in lung and kidney. Autopsies performed 30 s after injection of 125I-Factor Xa also demonstrated significant binding to the aorta and vena cava. These studies indicate that Factor Xa binds to specific thrombin-binding sites on endothelial cells, and that this binding alters its proteinase inhibitor specificity. Factor Xa binds to alpha 2-macroglobulin in vivo, whereas the predominant in vitro inhibitor of Factor Xa is alpha 1-proteinase inhibitor.


Subject(s)
Factor X/analysis , Protease Inhibitors/analysis , alpha-Macroglobulins/analysis , Animals , Antithrombin III/analysis , Aorta/analysis , Electrophoresis, Polyacrylamide Gel , Endothelium/analysis , Factor X/metabolism , Factor Xa , Humans , In Vitro Techniques , Kinetics , Mice , Tissue Distribution , Vena Cava, Inferior/analysis
3.
J Clin Invest ; 73(6): 1696-703, 1984 Jun.
Article in English | MEDLINE | ID: mdl-6202716

ABSTRACT

The regulation of human Factor IXa was studied in vitro in human and mouse plasma and in vivo in the mouse. In human plasma, approximately 60% of the 125I-Factor IXa was bound to antithrombin III (ATIII) by 2 h, with no binding to alpha 2-macroglobulin or alpha 1-proteinase inhibitor, as assessed by gel electrophoresis and IgG- antiproteinase inhibitor-Sepharose beads. In the presence of heparin, virtually 100% of the 125I-Factor IXa was bound to ATIII by 1 min. The distribution of 125I-Factor IXa in mouse plasma was similar. The clearance of 125I-Factor IXa was rapid (50% clearance in 2 min) and biphasic and was inhibited by large molar excesses of ATIII-thrombin and alpha 1-proteinase inhibitor-trypsin, but not alpha 2-macro-globulin-trypsin; it was also inhibited by large molar excesses of diisopropylphosphoryl - (DIP-) Factor Xa, DIP-thrombin, and Factor IX, but not by prothrombin or Factor X. The clearance of Factor IX was also rapid (50% clearance in 2.5 min) and was inhibited by a large molar excess of Factor IX, but not by large molar excesses of Factor X, prothrombin, DIP-Factor Xa, or DIP-thrombin. Electrophoresis and IgG- antiproteinase inhibitor-Sepharose bead studies confirmed that by 2 min after injection into the murine circulation, 60% of the 125I-Factor IXa was bound to ATIII. Organ distribution studies with 125I-Factor IXa demonstrated that most of the radioactivity was in the liver. These studies suggest that Factor IXa binds to at least two classes of binding sites on endothelial cells. One site apparently recognizes both Factors IX and IXa, but not Factor X, Factor Xa, prothrombin, or thrombin. The other site recognizes thrombin, Factor Xa, and Factor IXa, but not the zymogen forms of these clotting factors. After this binding, Factor IXa is bound to ATIII and the complex is cleared from the circulation by hepatocytes.


Subject(s)
Factor IX/metabolism , Protease Inhibitors/blood , Animals , Antithrombin III/metabolism , Endothelium/physiology , Factor IXa , Factor X/metabolism , Factor Xa , Humans , Iodine Radioisotopes , Isoflurophate/pharmacology , Kinetics , Mice , Species Specificity , Thrombin/metabolism , Tissue Distribution , alpha 1-Antitrypsin/metabolism , alpha-Macroglobulins/metabolism
4.
Cancer Res ; 55(17): 3803-9, 1995 Sep 01.
Article in English | MEDLINE | ID: mdl-7641197

ABSTRACT

Malignant gliomas will affect 15,000-17,000 Americans each year and carry a dismal prognosis. Adjuvant chemotherapy is hampered by inadequate drug delivery, systemic toxicity, and a markedly variable biological sensitivity. Intraarterial (i.a.) therapy may enhance selectivity by improving tumor drug delivery and reducing systemic toxicity. Using melphalan given i.a., we studied the therapy of intracranial human glioma xenografts in male athymic nude rats (mean weight, 300 g) which were inoculated intracerebrally with D-54 MG and D-456 MG. On Days 6 and 7 (D-54 MG) or Days 9 and 10 (D-456 MG), rats randomized by body weight and treated with single-dose melphalan given i.a. at 0.5 or 0.75 mg produced significantly higher median survival (D-54 MG, Days 33 and 32; D-456 MG, Days 52 and 54, respectively) compared with i.a. saline (D-54 MG, Day 14, P < 0.001; D-456 MG, Day 24, P = 0.000) or melphalan given i.v. at 0.75 mg and 0.9 mg (D-54 MG only; Day 19, P < 0.001; Day 23, P < 0.001, respectively) and at 0.5 and 0.75 mg (D-456 MG only; Day 26 for both doses, P = 0.00). Although a dose-dependent increase in median survival (D-54 MG, 0.25 mg, Day 18; 0.5 mg, Day 28.5; 0.75 mg, Day 32.5) was observed with i.a. administered melphalan, no significant difference was apparent between 0.5 and 0.75 mg in either tumor model (D-54 MG, P = 0.15; D-456 MG, P = 0.37). Toxicity studies in nontumor-bearing athymic rats yielded a maximum tolerated dose of 0.8 mg for i.a. administered melphalan. This dosage was superior in spite of different xenograft permeabilities (apparent mean blood-to-tissue transport [K] values for alpha-aminoisobutyric acid, 5.8 for D-54 MG and 1.3 for D-456 MG). Pharmacokinetic experiments demonstrated a significant first pass advantage for i.a. (versus i.v.) melphalan. The short plasma half-life, marked antiglioma activity, and lack of requirement for metabolic activation indicate that i.a. melphalan holds considerable promise for human glioma therapy.


Subject(s)
Brain Neoplasms/drug therapy , Glioma/drug therapy , Melphalan/administration & dosage , Animals , Brain/drug effects , Brain Neoplasms/metabolism , Brain Neoplasms/mortality , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Glioma/metabolism , Glioma/mortality , Humans , Injections, Intra-Arterial , Male , Melphalan/pharmacokinetics , Rats , Rats, Nude , Transplantation, Heterologous
5.
Cancer Res ; 53(10 Suppl): 2338-43, 1993 May 15.
Article in English | MEDLINE | ID: mdl-8485721

ABSTRACT

The addition of chemotherapy, notably using nitrosoureas, in the treatment of patients with glioblastoma multiforme has resulted in only modest improvements in long-term patient survival over the use of surgical intervention and irradiation alone. Intraarterial (i.a.) chemotherapy offers the potential benefit of increasing tumor drug delivery because of first-pass drug uptake, while minimizing systemic drug levels and toxicity. We have now investigated the i.a. therapy of intracerebral human glioma xenografts in athymic rats with 4-hydroperoxycyclophosphamide (4-HC), a preactivated derivative of cyclophosphamide. Athymic male rats were given intracerebral injections of the human glioma line D-54 MG. On Day 5 after injection, the rats were randomized (n = 8-10) by body weight (mean weight, approximately 300 g). In one set of experiments, each group received either i.v. saline, i.a. saline, 6 mg i.a. 4-HC, 6 mg i.v. 4-HC (6 mg), or 12 mg i.v. 4-HC. Intraarterial 4-HC produced significant increases in median survival (Day 24) compared with i.a. saline controls (140% increase), equivalent doses given i.v. (71% increase), and twice the equivalent dose given i.v. (50% increase) (by Wilcoxon rank sum analysis, P < 0.05 is statistically significant). The i.a. maximum tolerated dose was subsequently determined to be approximately 12.5 mg in non-tumor-bearing rats. Further experiments demonstrated a dose-response increase in survival for i.a. dosages of 6, 9, and 12.5 mg with significant improvement when compared with saline controls and 12.5 mg i.v. Pharmacokinetic experiments also demonstrated a significant first-pass uptake advantage for i.a. (versus i.v.) administered 4-HC. The short plasma half-life and marked antiglioma activity of 4-HC, without the need for hepatic activation, suggest a therapeutic application of this drug in the i.a. treatment of brain tumors.


Subject(s)
Brain Neoplasms/drug therapy , Cyclophosphamide/analogs & derivatives , Glioma/drug therapy , Animals , Body Weight/drug effects , Brain Neoplasms/metabolism , Cyclophosphamide/pharmacokinetics , Cyclophosphamide/pharmacology , Cyclophosphamide/toxicity , Dose-Response Relationship, Drug , Glioma/metabolism , Humans , Injections, Intra-Arterial , Injections, Intravenous , Male , Mice , Mice, Nude , Rats , Rats, Nude , Transplantation, Heterologous
6.
Cancer Res ; 54(17): 4710-4, 1994 Sep 01.
Article in English | MEDLINE | ID: mdl-8062269

ABSTRACT

We report the activity and toxicity of intrathecal melphalan in the treatment of human neoplastic meningitis in the subarachnoid space of athymic nude rats. Animals received injections via chronic indwelling subarachnoid catheters with 5 x 10(5) or 5 x 10(6) TE-671 human rhabdomyosarcoma cells or 5 x 10(6) D-54 MG human glioma cells and were treated with melphalan on days 8, 5, or 5, respectively. Melphalan toxicity in nontumor-bearing rats was assessed at single doses of a 2.0, 3.0, 4.0, or 5.0 mM solution, with clinical and histological evidence of neurotoxicity observed at the 4.0 and 5.0 mM levels. Multiple-dose toxicity studies using a dosing schedule of twice a week for two weeks with a 0.25, 0.5, 0.75, 1.0, 1.5, or 2 mM solution revealed dose-dependent clinical and histological evidence for toxicity at all dosages. Treatment of TE-671 with a single dose of 2.0 mM intrathecal melphalan produced an increase in median survival of 442% compared with saline controls (P < 0.003). Comparison of a single dose of 1.0 or 2.0 mM melphalan with a multiple dose regimen at 0.25 or 0.5 mM melphalan in the treatment of TE-671 revealed increases in median survival of 50% for 1.0 mM, 57% for 2.0 mM, 79% for 0.5 mM, and 111% for 0.25 mM concentrations. Comparison of a single dose of 1 mM melphalan with multiple doses of 0.25 mM melphalan in the treatment of D-54 MG revealed an increase in median survival of 475+% for each of the regimens. Intrathecal melphalan may be an important new addition in the treatment of neoplastic meningitis and is currently being evaluated clinically in a Phase 1 trial.


Subject(s)
Brain Neoplasms/drug therapy , Glioma/drug therapy , Melphalan/administration & dosage , Meningitis/drug therapy , Rhabdomyosarcoma/drug therapy , Animals , Brain Neoplasms/mortality , Demyelinating Diseases/chemically induced , Disease Models, Animal , Drug Screening Assays, Antitumor , Female , Glioma/mortality , Humans , Injections, Spinal , Melphalan/adverse effects , Meningitis/etiology , Meningitis/mortality , Rats , Rats, Nude , Rhabdomyosarcoma/mortality , Subarachnoid Space , Transplantation, Heterologous , Tumor Cells, Cultured
7.
Cancer Res ; 50(6): 1954-9, 1990 Mar 15.
Article in English | MEDLINE | ID: mdl-2306744

ABSTRACT

Neoplastic meningitis can result from leptomeningeal dissemination of a variety of cancers. We now report the development of animal models of human neoplastic meningitis and activity of intrathecal 4-hydroperoxycyclophosphamide (4-HC) against the human rhabdomyosarcoma cell line TE-671 and the human glioma cell line D-54 MG grown in the subarachnoid space of athymic rats. The injection of 5 x 10(5) TE-671 or D-54 MG cells resulted in leptomeningeal tumor growth from the base of the brain to the cauda equina. Daily weights and neurological examinations revealed progressive neurological deficits and weight loss, with death occurring between Days 21 and 27 for TE-671 and Days 14 and 26 for D-54 MG. 4-HC toxicity in non-tumor-bearing rats was assessed at dose levels of 2.0, 10.0, 15.0, and 20.0 mM, with clinical and histological evidence of neurotoxicity observed at the 2 highest dose levels. Intrathecal treatment with 4-HC on Day 8 following injection of TE-671 resulted in an increase in median survival of 20% (P = 0.04) at 1.0 mM 4-HC and 41% (P less than 0.001) at 2.5 mM 4-HC. Intrathecal treatment with 4-HC (2.5 mM) on Day 5 following injection of D-54 MG resulted in an increase in median survival of 23% (P = 0.009). These studies show the usefulness of the athymic rat model of human neoplastic meningitis and demonstrate the efficacy in vivo of intrathecally administered 4-HC against a human glioma and a human rhabdomyosarcoma cell line and the lack of toxicity at therapeutic levels of 4-HC in normal athymic rats.


Subject(s)
Antineoplastic Agents/administration & dosage , Cyclophosphamide/analogs & derivatives , Meningeal Neoplasms/drug therapy , Meningitis/drug therapy , Spinal Cord Neoplasms/drug therapy , Animals , Cell Line , Cyclophosphamide/administration & dosage , Cyclophosphamide/therapeutic use , Female , Humans , Injections, Spinal , Meningeal Neoplasms/pathology , Meningitis/etiology , Neoplasm Transplantation , Rats , Rats, Nude , Rhabdomyosarcoma/drug therapy , Spinal Cord Neoplasms/pathology , Transplantation, Heterologous
8.
Oncogene ; 10(11): 2243-6, 1995 Jun 01.
Article in English | MEDLINE | ID: mdl-7784070

ABSTRACT

The high incidence of loss of chromosome 10 alleles in glioblastoma multiforme suggests the presence on this chromosome of a tumor suppressor gene that is important in glioma tumorigenesis and progression. Our initial deletion mapping studies using restriction fragment length polymorphism markers indicated a common deletion region in 10q24-qter. In an attempt to localize the deleted region further, we screened a panel of 117 gliomas for loss of heterozygosity for chromosome 10 loci using 10 microsatellite markers. Seventeen tumors showed partial loss of a copy of chromosome 10 and were further analysed using 28 additional microsatellite markers. Of these, 10 had terminal deletion in the q arm, three had deletions in both p and q arms, two contained interstitial deletion in 10q and two carried deletions in 10p. In the 15 tumors with deletions in 10q, the minimal overlapping deletion region was in distal 10q between markers D10S587 and D10S216. Loci D10S587 and D10S216 are approximately mapped to a 5 cM region in 10q25.1.


Subject(s)
Brain Neoplasms/genetics , Chromosome Deletion , Chromosomes, Human, Pair 10 , Glioma/genetics , Heterozygote , Humans , Tumor Cells, Cultured
9.
Biochim Biophys Acta ; 716(2): 151-7, 1982 May 27.
Article in English | MEDLINE | ID: mdl-6178438

ABSTRACT

The clearances of 125I-labeled alpha 1-proteinase inhibitor-trypsin, antithrombin III-thrombin and alpha 2-macroglobulin-methylamine (CH3NH2) were compared in our previously described mouse model. alpha 1-Proteinase inhibitor-trypsin cleared with a t 1/2 of 20 min, antithrombin III-thrombin of 7 min and 125I-labeled alpha 2-macroglobulin-methylamine of 2 min. Competition studies were performed to determine whether one or several pathways clear these three ligands. The clearance of 125I-labeled alpha 1-proteinase inhibitor-trypsin and 125I-labeled antithrombin III-thrombin was blocked by large molar excesses of either ligand, but not by alpha 2-macroglobulin-methylamine. The clearance of 125I-labeled alpha 2-macroglobulin-methylamine can be blocked by a large molar excesses of unlabeled alpha 2-macroglobulin-methylamine but not by alpha 1-proteinase inhibitor-trypsin. These studies demonstrate that the clearance of alpha 1-proteinase inhibitor-trypsin complexes is independent of alpha 2-macroglobulin-methylamine and utilizes the same pathway which is involved in the clearance of antithrombin III-thrombin complexes.


Subject(s)
Antithrombin III/metabolism , alpha 1-Antitrypsin/metabolism , alpha-Macroglobulins/metabolism , Animals , Binding, Competitive , Electrophoresis, Polyacrylamide Gel , Female , Methylamines/metabolism , Mice , Thrombin/metabolism , Tissue Distribution , Trypsin/metabolism
10.
Clin Cancer Res ; 1(12): 1545-55, 1995 Dec.
Article in English | MEDLINE | ID: mdl-9815955

ABSTRACT

LMB-1 (B3-LysPE38) is an immunotoxin composed of the tumor-reactive monoclonal antibody B3 and a genetically engineered form of Pseudomonas exotoxin. Monoclonal antibody B3 reacts with a carbohydrate epitope that is found on a number of solid tumors (e.g., breast, ovarian, and lung carcinomas) that frequently invade the intrathecal space, causing neoplastic meningitis. The Pseudomonas exotoxin has been engineered to remove the binding domain to eliminate nonspecific binding. A model of human neoplastic meningitis using rats bearing the human epidermoid carcinoma A431 was used for therapeutic studies of immunotoxin LMB-1. Therapy was initiated 3 days after injection of the tumor cells, which was one third of the median survival time of untreated rats. A single intrathecal injection of 40 microgram increased median survival from 9 days with saline injection to 16 days (78%, P < 0.001), and a single dose of 200 microgram increased median survival to 25 days (188%, P < 0. 001). Three doses of 40 or 200 microgram given on days 3, 6, and 8 significantly increased the median survival of 9.5 days associated with saline injection to 40.5 days (326% increase) and 33.0 days (247% increase), respectively, with two long-term survivors (191-day survival) in each treatment group. LMB-1 had no therapeutic effect on the treatment of two B3 antigen-negative neoplastic meningitis models. Treatment of the antigen-positive A431 neoplastic meningitis with B3 alone or a nonspecific monoclonal, MOPC, coupled to the engineered Pseudomonas exotoxin produced no survival effects. Nontumor-bearing athymic rats showed no toxicity with a single dose of either 40 microgram or 200 microgram, or 3 doses of 40 microgram. However, when they were given three doses of 200 microgram, these rats showed weight loss and loss of neurological function, and two of eight animals died. These studies indicate that, in the range of the most therapeutically effective dosage, the immunotoxin LMB-1 is tolerated in the intrathecal space and should be considered for human intrathecal trials.


Subject(s)
ADP Ribose Transferases , Antibodies, Monoclonal/administration & dosage , Bacterial Toxins , Carcinoma/therapy , Exotoxins/administration & dosage , Immunotoxins/administration & dosage , Lewis Blood Group Antigens/immunology , Meningeal Neoplasms/therapy , Virulence Factors , Animals , Carcinoma/immunology , Carcinoma/pathology , Disease Models, Animal , Drug Screening Assays, Antitumor , Humans , Meningeal Neoplasms/immunology , Meningeal Neoplasms/pathology , Rats , Rats, Nude , Tumor Cells, Cultured , Pseudomonas aeruginosa Exotoxin A
11.
Arch Intern Med ; 146(1): 188-91, 1986 Jan.
Article in English | MEDLINE | ID: mdl-2935105

ABSTRACT

Releasable tissue plasminogen activator (t-PA) and the fast inhibitor of t-PA were measured in 18 controls and a pedigree with venous thrombosis. The functional assay was performed by a technique that destroys the t-PA inhibitor when blood is drawn. It was found that activator and inhibitor levels varied widely in the control group. One patient demonstrated inhibitor levels, on two different occasions, of 2.82 and 3.54 IU of t-PA per milliliter of plasma, as compared with a releasable activator level of 1.87 IU/mL. The t-PA antigen levels of this patient and the remainder of the pedigree were essentially normal for all seven subjects. Thus, it is suggested that the previously reported fibrinolytic disorder in this pedigree represents an imbalance between activator and inhibitor levels rather than an actual deficiency of t-PA.


Subject(s)
Fibrinolysis , Tissue Plasminogen Activator/blood , Antigens/analysis , Blood Proteins/metabolism , Glycoproteins/metabolism , Humans , Mesenteric Veins , Pedigree , Protein C , Protein S , Pulmonary Embolism/blood , Pulmonary Embolism/genetics , Thrombosis/blood , Thrombosis/genetics , Tissue Plasminogen Activator/antagonists & inhibitors , Tissue Plasminogen Activator/immunology
12.
Am J Med ; 79(4): 407-11, 1985 Oct.
Article in English | MEDLINE | ID: mdl-3931468

ABSTRACT

Releasable vascular plasminogen activator was measured in 28 patients (14 males and 14 females) with a history of thrombotic strokes documented by computed tomographic scanning. Levels were compared with those in a control population of 126 healthy subjects with no history of thromboembolic disease. The patient population tended to have higher levels of activator than the control population, 0.53 Committee on Thrombolytic Agents (CTA) units/ml of plasma for patients versus 0.21 CTA units/ml for control subjects; however, there was a wide distribution of values, as reported in all previous populations. Since plasminogen activator levels distribute in a non-Gaussian manner, patient values and control values were stratified into deciles. By this approach, the distribution among the patient was not significantly different from that among the control subjects except in females, who demonstrated skewing to higher deciles (p = 0.019). It is concluded that thrombotic strokes are not associated with low levels of releasable vascular plasminogen activator, and in fact, these patients may present with levels considerably above the mean for normal subjects.


Subject(s)
Cerebrovascular Disorders/blood , Tissue Plasminogen Activator/blood , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Sex Factors , Thrombosis/blood , Thrombosis/etiology , Tissue Plasminogen Activator/deficiency
13.
Thromb Haemost ; 48(2): 208-10, 1982 Oct 29.
Article in English | MEDLINE | ID: mdl-6758181

ABSTRACT

Radiolabeled alpha 2-antiplasmin cleared slowly from the circulation of mice. Complex formation with either plasmin or trypsin resulted in a significant increase in the plasma elimination rate of the protease inhibitor. Approximately 20 min and 14 min were required for 50% of the injected alpha 2-antiplasmin-plasmin and alpha 2-antiplasmin-trypsin to clear from the circulation, respectively. Significant competition was observed when radiolabeled alpha 2-antiplasmin-plasmin was cleared in the presence of a large molar excess of unlabeled alpha 2-antiplasmin-plasmin. alpha 1-Antitrypsin-trypsin failed to complete with radiolabeled alpha 2-antiplasmin-plasmin even when present at 2000 fold molar excess. Organ distribution studies localized the major site of alpha 2-antiplasmin-plasmin clearance in the liver. Microscopic autoradiography data suggested that the cell responsible for the clearance pathway was the hepatocyte.


Subject(s)
Peptide Hydrolases/metabolism , Plasma/metabolism , alpha-2-Antiplasmin/metabolism , Animals , Binding, Competitive , Female , Liver/cytology , Liver/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred DBA , Protease Inhibitors/pharmacology , Radioligand Assay
14.
Thromb Res ; 41(5): 707-15, 1986 Mar 01.
Article in English | MEDLINE | ID: mdl-3485835

ABSTRACT

Antithrombin III (ATIII) is an anticoagulant protein which binds and inactivates thrombin and other serine proteinases. Little is known about regulation of its synthesis. We confirm that ATIII is synthesized by isolated rat hepatocytes, and that its synthesis is not altered by direct feedback of its complexes with proteinases. Neither is hepatocyte synthesis of ATIII altered by supernatants from macrophages cultured in the presence of ATIII-proteinase complexes. However, culture of macrophages with fibrinogen fragment D results in production of a factor(s) in the macrophage supernatants which stimulates hepatic fibrinogen synthesis, as previously described, and also stimulates the synthesis of ATIII and alpha 1-proteinase inhibitor (alpha 1PI). Synthesis of albumin and rat alpha 2-macroglobulin (alpha 2M) is not (alpha 2M) is not altered. Culture of macrophages in the presence of bacterial endotoxin also results in release of a factor(s) into the medium which stimulates the same changes in hepatocyte protein synthesis. These results show for the first time a mechanism by which synthesis of ATIII can be regulated during coagulation and fibrinolysis.


Subject(s)
Antithrombin III/biosynthesis , Blood Proteins/biosynthesis , Liver/metabolism , Macrophages/physiology , Animals , Cells, Cultured , Fibrin Fibrinogen Degradation Products/pharmacology , Rats , alpha 1-Antitrypsin
15.
Neurosurgery ; 41(6): 1365-72; discussion 1372-3, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9402588

ABSTRACT

OBJECTIVE: The promise of immunotherapies developed against brain tumors in animal models has not been realized in human clinical trials. This may be because of the routine use of rodent tumors artificially induced by chemicals or viruses that do not accurately portray the intrinsic qualities of spontaneously arising human tumors and that often fail to incorporate the role of immunosuppressants, such as transforming growth factor-beta, that are secreted by human gliomas. From an astrocytoma that arose spontaneously in inbred VM/Dk mice, we have characterized a highly tumorigenic spontaneous murine astrocytoma cell line (SMA-560) that retains features of glial differentiation and naturally produces high levels of biologically active transforming growth factor-beta. We have used this model to determine whether cytokine production by tumor cells will inhibit intracerebral astrocytoma growth. METHODS: Packaging cell lines producing replication-incompetent retroviral vectors were used to transfect the SMA-560 cell line in vitro with the genes encoding the murine cytokines interleukin (IL)-2, IL-3, IL-4, IL-6, tumor necrosis factor-alpha, gamma-interferon, or granulocyte-macrophage colony-stimulating factor or the costimulatory molecule B7.1 (CD80). RESULTS: Mice challenged intracerebrally with 5000 untransfected SMA-560 cells all succumbed to tumor within 30 days, with a median survival of 25 days. In contrast, mice challenged with SMA-560 cells producing IL-2, IL-4, or tumor necrosis factor-alpha each had a more than 400% increase in median survival (P < 0.0001). In these groups, 78.3% (18 of 23 mice), 66.7% (10 of 15 mice), and 60% (6 of 10 mice) of the mice, respectively, remained alive without evidence of tumor for longer than 100 days after the initial tumor challenge. All other cytokines tested and the expression of B7.1 failed to result in an increase in median survival. CONCLUSION: Using a spontaneous astrocytoma model in an inbred mouse strain, we have shown that cytokine production by glial tumors can abrogate their tumorigenicity in vivo despite production of transforming growth factor-beta. These results predict that approaches directed at cytokine production within intracerebral astrocytomas may be efficacious in human trials and that the "immunological privilege" of the brain may not be absolute under such conditions.


Subject(s)
Astrocytoma/metabolism , Astrocytoma/pathology , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cytokines/metabolism , Animals , Carcinogenicity Tests , Female , Genetic Vectors , Histocompatibility Antigens Class I/analysis , Immunohistochemistry , Mice , Mice, Inbred Strains , Retroviridae/genetics , Transfection , Transforming Growth Factor beta/biosynthesis , Tumor Cells, Cultured
16.
Clin Neuropathol ; 23(1): 34-43, 2004.
Article in English | MEDLINE | ID: mdl-14986932

ABSTRACT

OBJECTIVE: Extracranial subcutaneous masses involving the scalp and/or skull in young children are uncommon lesions that get excised by the neurosurgeon. Although the most common reported lesion is the dermoid cyst, our experience suggests that the spectrum of pathology in these lesions can present diagnostic challenges to the pathologist. MATERIAL: We reviewed 30 consecutive extracranial masses from 29 patients between July 1998 and June 2003. METHOD: Hematoxylin and eosin-stained sections were reviewed in all cases, and immunohistochemistry was performed in select cases. RESULTS: Twenty-three were within the scalp, 5 involved the scalp and skull and 2 were within the limits of the inner and outer tables of the skull. There were 8 dermoid cysts, 2 epidermoid cysts, 6 post-traumatic lesions including 3 calcified cephalhematomas and 3 pseudocysts, 5 vascular lesions including 3 capillary hemangiomas, 1 venous angioma and 1 lymphangioma, 2 cases of cranial fasciitis and 1 case each of benign teratoma, deep granuloma annulare, benign fibrous histiocytoma, congenital melanocytic nevus, hamartoma with ectopic meningothelial elements, cutaneous hyalinised ectopic meningioma and a meningocele with a fibrohistiocytic reaction. No lesions have recurred or exhibited malignant features. CONCLUSIONS: Surgical pathologists and neuropathologists should be aware that the differential diagnosis of "lumps and bumps on babie's heads" is quite varied and can be histologically challenging.


Subject(s)
Hamartoma/pathology , Head and Neck Neoplasms/pathology , Scalp/pathology , Skin Neoplasms/pathology , Skull Neoplasms/pathology , Skull/pathology , Child, Preschool , Craniocerebral Trauma/pathology , Diagnosis, Differential , Female , Head and Neck Neoplasms/congenital , Humans , Infant , Infant, Newborn , Male , Retrospective Studies , Scalp/injuries , Skin Neoplasms/congenital , Skull/injuries , Skull Neoplasms/congenital
17.
Clin Neuropathol ; 17(1): 55-60, 1998.
Article in English | MEDLINE | ID: mdl-9496542

ABSTRACT

Twenty-nine months after surgery, irradiation, and systemic chemotherapy for a pineal mixed germ cell tumor, an 11-year-old Caucasian male developed a 3 cm dural based nodule in the occipital lobe that proved to be a solitary fibrous tumor by immunohistochemical and ultrastructural examination. Differential diagnosis included fibrous meningioma, neurofibroma, Schwannoma, cranial fasciitis of infancy, and solitary fibrous tumor. A Masson trichrome stain revealed a prominent collagenous stroma and reticulin staining exhibited strong pericellular positivity. Immunohistochemical staining demonstrated diffuse vimentin and focal CD34 positivity of tumor cells. Ultrastructural examination revealed fibroblastic differentiation. These features are consistent with solitary fibrous tumor. Although we favor a radiation-induced origin for the neoplasm, alternative explanations for the tumor's origin include cerebrospinal fluid spread from the original germ cell tumor or a de novo neoplasm.


Subject(s)
Antineoplastic Agents/therapeutic use , Endocrine Gland Neoplasms/therapy , Germinoma/therapy , Meningeal Neoplasms/etiology , Pineal Gland , Child , Combined Modality Therapy , Diagnosis, Differential , Endocrine Gland Neoplasms/radiotherapy , Germinoma/radiotherapy , Humans , Immunohistochemistry , Magnetic Resonance Imaging , Male
18.
Surg Neurol ; 40(4): 278-83, 1993 Oct.
Article in English | MEDLINE | ID: mdl-8211637

ABSTRACT

Supratentorial embryonal neuroepithelial tumors are undifferentiated neoplasms. We have used this term in preference to the controversial classification primitive neuroectodermal tumors (PNET). These lesions in children are malignant neoplasms which are usually fatal within 2 years of diagnosis in spite of therapy with surgery, radiotherapy, and chemotherapy. We have adopted an aggressive approach to the treatment of these tumors with surgical resection, hyperfractionated craniospinal irradiation of 30.6-43.9 Gy followed by a tumor boost to a total dose of 50-63.7 Gy, and adjuvant chemotherapy with cyclophosphamide, vincristine, and cis-platinum. We have treated five children, aged 4-18 years, with this approach. In contrast to the results reported in the literature, four children are alive without evidence of tumor from 4.3 to 8.0 years following diagnosis. One has suffered a tumor relapse at 2.3 years following diagnosis but remains alive. The basis of our therapeutic strategy for childhood supratentorial embryonal neuroepithelial tumors and the implications of our clinical results are discussed.


Subject(s)
Cerebellar Neoplasms/radiotherapy , Cerebellar Neoplasms/surgery , Chemotherapy, Adjuvant , Neoplasms, Germ Cell and Embryonal/radiotherapy , Neoplasms, Germ Cell and Embryonal/surgery , Adolescent , Brain/radiation effects , Cerebellar Neoplasms/drug therapy , Child , Child, Preschool , Combined Modality Therapy , Female , Humans , Male , Neoplasms, Germ Cell and Embryonal/drug therapy , Spinal Cord/radiation effects , Tomography, X-Ray Computed
19.
J Pediatr Surg ; 36(9): 1381-6, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11528610

ABSTRACT

BACKGROUND/PURPOSE: Diagnosis and management of the acute abdomen in patients with spina bifida (SB) can be problematic. There are at least 4 clinical factors that can predispose to the development of acute abdominal symptoms and signs, and patients with a thoracic level lesion can have a partially insensate abdomen. The authors analyzed their accumulated experience to determine the annual incidence of acute abdominal signs and symptoms in children and young adults with spina bifida, the differential diagnosis, the operative management, and the outcome. The pertinent literature was reviewed. METHODS: Cases were ascertained during a 10-year period at 1 institution and reviewed retrospectively. RESULTS: Twenty-two episodes of acute abdominal symptoms and signs in 19 children and young adults with SB were ascertained over 10 years at 1 institution, for an annual incidence of 0.74%. More patients had a thoracic level lesion (n = 12; 60%) than in the clinic population as a whole (27%; P =.04), but the gender distribution was similar (58% girls), as was the prevalence of ventriculoperitoneal shunts (VPS; 95%). The median age was 13 years (range, 1 year to 26 years). Hospitalization was necessary for 19 (86%) of the 22 episodes. The duration of symptoms before diagnosis was a median of 3 days (range, 1 to 14 days). Most patients (82%) presented with abdominal pain. Fever was present in 27%, shock in 23%, and peritoneal signs in 23%. There were 14 different final diagnoses, 10 (71%) of which were associated with a predisposing factor. Of the 22 episodes, 18 (82%) could be attributed to an underlying factor: (1) neurogenic bladder (9; 41%); (2) neurogenic bowel (3; 14%); (3) VPS (4; 18%); (4) complications from previous surgery (2; 9%). Thirteen patients (59%) underwent a total of 20 surgical procedures of 12 different kinds. Despite awareness of the complexities involved, 3 patients (14%) died: 1 from complications resulting from bladder perforation; 1 from urosepsis and shock; and 1 from peritonitis caused by VPS infection. CONCLUSION: The differential diagnosis of the acute abdomen in patients with SB is broad, conditions requiring surgery are frequently diagnosed, and the mortality rate is substantial, despite aggressive management.


Subject(s)
Abdomen, Acute/diagnosis , Abdomen, Acute/epidemiology , Spinal Dysraphism/epidemiology , Adolescent , Adult , Age Distribution , Child , Child, Preschool , Comorbidity , Female , Humans , Incidence , Male , Prognosis , Risk Assessment , Risk Factors , Sex Distribution , Spinal Dysraphism/diagnosis , Spinal Dysraphism/surgery
20.
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