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Biomedical subjects

J J Corrigan

Publications and source records attributed to J J Corrigan.

At least 19 recordsLinked to original sources
PubMed1992

Tissue-type plasminogen activator, plasminogen activator inhibitor, and histidine-rich glycoproteins in stressed human newborns.

Normal newborns have reduced levels of tissue-type plasminogen activator (tPA). Stressed newborns have an increased prevalence of thrombotic diseases. An impaired release of tPA and/or increased plasminogen activator inhibitor (PAI) is associated with thrombotic risk in the adult patient. The purpose of this study was to assay the plasma levels of tPA, PAI, histidine-rich glycoprotein (HRG), and other fibrinolytic proteins in 15 severely stressed newborns. The stressed babies showed significantly higher (p less than .001) levels of tPA antigen compared with normal newborns. Also, PAI activity and PAI-1 antigen levels were increased. Levels of both HRG and plasminogen were higher in the stressed group but the ratio of HRG to plasminogen was the same as that in the normal control newborns (1:3), suggesting an insignificant effect of HRG. D-dimers were significantly elevated in the stressed newborns. However, 8 patients died and 4 of these were found to have massive thrombotic disease on autopsy. These results show that the newborn when stressed will increase tPA levels and activate the lytic system. However, the activity is suboptimal inasmuch as PAI activity did not decrease and thrombotic disease was observed.

Female↗
PubMed1991

Measurement of serum granulocyte colony-stimulating factor in a patient with congenital agranulocytosis (Kostmann's syndrome).

A 12-month-old boy with Kostmann's syndrome was admitted with cavitary pulmonary disease. He had also had bacterial conjunctivitis, periorbital cellulitis, pneumonitis, and otitis media since the age of 10 days. His umbilical cord had not fallen off until he was 3 weeks old. Neutropenia was diagnosed at 4 weeks of age. Antineutrophil antibody studies were negative. A bone marrow aspirate showed granulocytic hypoplasia and a maturation arrest at the promyelocyte stage. Hematopoietic cell culture showed normal numbers of colony-forming units-granulocyte macrophage. Serum granulocyte-macrophage colony-stimulating factor level, was 0.24 ng/mL (normal, greater than 0.05 ng/mL). Serum granulocyte colony-stimulating factor levels, measured by enzyme immunoassay, were undetectable. The patient was successfully treated with filgrastim (granulocyte colony-stimulating factor), with an increase in the absolute neutrophil count to 10.0 x 10(9)/L. Thus, our case of Kostmann's syndrome appears to represent a defect in regulation or production of granulocyte colony-stimulating factor.

Agranulocytosis↗
PubMed1991

A variant form of thrombasthenia.

We encountered two siblings with abnormal bruising since infancy. Studies revealed functional platelet defects characterized by a lack of platelet aggregation and adenosine triphosphate release on exposure to adenosine diphosphate and collagen as well as variable responses with ristocetin (at concentrations of less than or equal to 1.25 g/L) and arachidonic acid. In addition, little or no platelet aggregation was observed after exposure to hexadimethrine bromide (Polybrene), the calcium ionophore A23187, and the thromboxane/endoperoxide analogue U46619. The membrane proteins IIIa and Ib were present, as determined with monoclonal antibody testing, and no platelet-associated IgG was found. Platelet analysis with routine electron microscopy and ultrastructural cytochemistry revealed normal morphologic features and no deficiencies in the number of alpha granules dense bodies and other organelles. The platelet abnormality may represent a new variant of thrombasthenia.

Adenosine Diphosphate↗
PubMed1990

Histidine-rich glycoprotein and plasminogen plasma levels in term and preterm newborns.

The newborn's fibrinolytic system is not the same as that in the adult. Hypoplasminogenemia with normal (adult) levels of alpha 2-plasmin inhibitor and plasminogen activator inhibitor are characteristic of the newborn's lytic system. This combination suggests that the newborn may have an impaired lytic system that may explain, in part, the thrombotic events that are frequently observed. Histidine-rich glycoprotein (HRG), another fibrinolytic inhibitor, retards fibrinolysis by interfering with plasminogen's binding to fibrin. Levels of HRG have been reported to be reduced in term newborns. This finding has not been studied recently and to our knowledge, there are no reports of HRG levels in premature infants. The purpose of this study was to measure the plasma levels of HRG and plasminogen in three groups of patients: normal adults (n = 48), normal term newborns (n = 43), and normal premature newborns (n = 18). The protein levels were determined by electroimmunoassay. Cross-immunoelectrophoresis was also performed for HRG. Cord blood was employed for obtaining newborn citrated plasma. The newborns had significantly lower plasminogen and HRG levels when compared with those of the adults. Also, the HRG levels of the premature newborns were lower than those of the term newborns. In conclusion, the newborns had lower levels of HRG than adults, with premature newborns having the lowest levels. This may allow for more plasminogen to be available for fibrin binding even though newborns have hypoplasminogenemia.

Adult↗
PubMed1990

Effects of chronic beta-carotene supplementation on vitamin K status in adults.

Plasma vitamin K concentrations and prothrombin coagulation activity were determined in 26 normal adults who had received daily beta-carotene supplementation (0, 15, 30, or 60 mg) for six months. Neither plasma vitamin K nor coagulation activity were significantly decreased at any supplementation level. Thus, chronic beta-carotene supplementation, even at high daily doses, is not expected to result in clinical vitamin K deficiency. The data suggest separate mechanisms for intestinal absorption of beta-carotene and vitamin K.

Aged↗
PubMed1990

Hepatic impairment in fetuses of preeclamptic mothers.

Cord blood from preeclamptic and normal gestations were analyzed for the vitamin K-dependent proteins, factors II, VII, IX, X, and protein C, and for fibrinogen and albumin. Factor II, factor IX, protein C, and albumin protein levels were reduced in the preeclamptic group, whereas there was no significant change in the fibrinogen or factor X protein levels. The data suggest that these findings are probably due to decreased synthesis and are not indicative of vitamin K deficiency.

Albumins↗
PubMed1990

Mojave rattlesnake (Crotalus scutulatus scutulatus) venom: in vitro effect on platelets, fibrinolysis, and fibrinogen clotting.

Rattlesnake envenomation commonly produce defects in the hemostatic mechanism. However, Mojave rattlesnake (Crotalus scutulatus scutulatus) envenomation has been reported not to cause a systemic bleeding diathesis. In this study, whole venom from the Mojave rattlesnake was tested in vitro for fibrinogen clotting activity, ability to induce platelet aggregation, and for fibrinolytic activity. The Mojave venom caused no fibrinogen clotting and it displayed very weak ability to cause platelet aggregation and fibrinolytic activity. These in vitro studies support the clinical observation that Mojave envenomation does not cause a coagulopathy.

Animals↗
PubMed1989

Newborn's fibrinolytic mechanism: components and plasmin generation.

Plasminogen activity and antigen, tissue-type plasminogen activator (tPA) activity and antigen, plasminogen activator inhibitor (PAI) activity, and plasmin generation rates were determined in 32 normal newborn plasmas and 25 normal adult plasmas. The newborns showed reduced levels of plasminogen activity and antigen and tPA antigen, and activity, normal levels of PAI activity, and slower plasmin generation rates. The slower generation was shown to be due to the hypoplasminogenemia. The in vitro plasmin generation studies also showed that the newborn needed 11 times the usual concentration of urokinase and 5 times the usual concentration of tPA to achieve the minimal activation rate of the adult.

Caseins↗
PubMed1989

Hemostatic markers in acute stroke.

To assess the time course of thrombosis and fibrinolysis after acute stroke, we measured concentrations of fibrinopeptide A (FpA), B-beta 1-42 peptide (B-beta 1-42), B-beta 15-42 peptide (B-beta 15-42), and crosslinked D-dimer (XDP) in 31 patients at varying times following acute ischemic stroke and in 13 neurologically stable patients with chronic strokes. FpA levels were markedly elevated during the first week after stroke and declined slowly during the first month. Mean FpA levels were not significantly elevated in chronic stroke patients. Mean XDP levels were slightly elevated during the first week and increased during the next 2 weeks after stroke. B-beta 1-42 and B-beta 15-42 levels were not elevated at any time following acute stroke. Our data suggest that fibrin formation greatly exceeds endogenous fibrinolysis during the acute phase of ischemic stroke. Endogenous fibrinolysis develops slowly following stroke. Prolonged elevation of FpA concentration suggests that thrombin activity and fibrin formation continue for up to 4 weeks in some patients with ischemic stroke.

Acute Disease↗
PubMed1988

Fibrin metabolism in patients with acute myocardial infarction during and after treatment with tissue-type plasminogen activator.

In order to define some of the determinants of successful thrombolysis and reocclusion during fibrinolytic therapy for acute myocardial infarction (AMI), specific molecular markers of fibrin metabolism were serially measured in 15 patients with AMI treated with tissue-type plasminogen activator (t-PA). Fibrin formation was assessed by measurement of fibrinopeptide A (FpA) and fibrinolysis by assay of B-beta peptides 1-42 and 15-42 and crosslinked fibrin degradation products (XDP). At baseline, FpA levels were high while markers of fibrinolysis were near normal. Following a 90-minute infusion of t-PA (0.5-1.1 mg kg-1 hr-1), all markers of fibrinolysis increased. Levels of FpA remained elevated despite heparin at the initiation of cardiac catheterization. None of these markers discriminated between patients with successful reperfusion from those without. At 4 hours, B-beta 15-42 peptide and XDP levels remained elevated suggesting persistence of fibrinolysis beyond the short circulatory half-life of t-PA. FpA levels at 4 hours were lower in patients who underwent acute coronary angioplasty compared to those who received additional low dose t-PA (12.3 +/- 4.5 vs. 30.4 +/- 5.5 ng/ml, p less than 0.05). By 48 hours, markers of fibrinolysis had returned toward normal except in 2 patients with persistently elevated B-beta 15-42 peptide levels who suffered reocclusion on days 5 and 6 (75 and 44 vs. 29 +/- 3 nM, p less than 0.005). In conclusion, molecular markers of fibrin metabolism during fibrinolytic therapy may provide clinically relevant data.

Angioplasty, Balloon↗
PubMed1988

Neonatal thrombosis and the thrombolytic system: pathophysiology and therapy.

In older children and adults the use of thrombolytic drugs appears to be a promising medical approach to thromboembolic disease. However, experience in newborns is limited, with both failure and success having been reported. In this article, the fibrinolytic mechanism is delineated. The similarities and differences in this mechanism between newborns and adults are indicated. It is clear that our understanding of the newborn's fibrinolytic system is limited. Thrombolytic therapy is reviewed. It is recommended that future clinical studies be designed to include three essential features: (a) a uniform clinical staging, (b) a dose-response relationship with a plasminogen activator based on in vivo and in vitro studies, and (c) detailed studies of the newborn's fibrinolytic mechanism before and during thrombolytic therapy.

Fibrinolysis↗