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Biomedical subjects

T M Cosgriff

Publications and source records attributed to T M Cosgriff.

At least 37 records · Page 2Linked to original sources
PubMed1986

The hemostatic derangement produced by T-2 toxin in cynomolgus monkeys.

T-2 toxin, a mycotoxin produced by several strains of the genus Fusarium, has been implicated as a cause of serious illness in both animals and man. Hemorrhage is a feature of the syndromes which have been described. An LD20 dose of T-2 was administered im to adult cynomolgus monkeys. This resulted in prolongation of prothrombin and activated partial thromboplastin times and a decrease in multiple coagulation factors. These changes were detected within hours of toxin administration, were maximal at 24 hr, and returned to normal over the next 3 days. Fibrin-fibrinogen degradation products were not detected at any time point. Repeated phlebotomy produced a significantly greater increase in platelet count in control monkeys, which could be taken as evidence for an effect of toxin on platelet kinetics. In treated animals, the hematocrit level declined by about 10%, but a similar decrease occurred in control animals. The white blood cell count increased 4 to 5 times over pretreatment values. Despite the changes in multiple laboratory parameters, treated monkeys did not exhibit clinical evidence of hemorrhage. In three animals which died as a result of toxicosis, necropsy revealed mild petechial hemorrhage involving the colon and heart, as well as necrosis of lymphoid tissues.

Analysis of Variance↗
PubMed1985

Mefloquine failure in a case of falciparum malaria induced with a multidrug-resistant isolate in a non-immune subject.

In a volunteer with infection induced by injection of the mefloquine-sensitive, multidrug-resistant Vietnam Smith isolate of P. falciparum, parasitemia recurred following treatment with the candidate antimalarial drug enpiroline. Parasitemia also recurred after subsequent treatment with mefloquine and again after retreatment with the same drug. All recurrences were at the RI level. Parasite drug sensitivities determined by a semi-automated isotope microdilution method after the second and third recurrences revealed a progressive decrease in sensitivity to all arylaminoalcohols tested (halofantrine, enpiroline, and mefloquine). Decreased sensitivity persisted after 30 days of isolate culture. The parallel changes in parasite sensitivity to the synthetic arylaminoalcohols argue for development of drugs which are chemically dissimilar.

Adult↗
PubMed1984

Hematological and bone marrow effects of ribavirin in rhesus monkeys.

Ribavirin (Virazole, 1-beta-D-ribofuranosyl-1,2,4-triazole-3-carboxamide), a broad-spectrum antiviral compound, was evaluated for effects on blood and bone marrow of rhesus monkeys when administered by intramuscular injection for 10 days in doses of 30 or 100 mg/kg/day (four monkeys/group). Both groups developed a normochromic, normocytic anemia that was mild in the low-dose group and severe in the high-dose group. A dose-related erythroid hypoplasia occurred during the treatment period. Myeloid precursors were not affected. Differential counts of erythroid precursors showed a significant decrease in late erythroid forms while early erythroid forms were either unchanged or increased. Megakaryocyte numbers were increased in both groups. Qualitative changes in marrow cells included vacuolization of erythroid precursors and of occasional white cell precursors and megakaryocytes, and the appearance of bone marrow histiocytes containing red cells in various stages of disintegration. Thrombocytosis occurred in both treatment groups, with platelet counts returning to control values after drug withdrawal. Platelet function was not affected by treatment. No drug-related changes were seen during the treatment period for total and differential leukocyte counts, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. Reticulocyte counts and mean corpuscular volume increased after treatment then returned to control values. Osmotic fragility of erythrocytes was not changed. These data show that in monkey, ribavirin causes a dose-related decrease in circulating red blood cell mass that is due in part to suppression of late erythroid precursors in bone marrow. These effects are reversible when treatment is discontinued and are not predictive of potentially serious or lasting untoward effects of ribavirin.

Animals↗
PubMed1984

The hemostatic derangement produced by T-2 toxin in guinea pigs.

T-2 toxin produced significant coagulation abnormalities when administered parenterally to Hartley strain guinea pigs. The animals developed depressed activity of all coagulation factors except fibrinogen. Platelet aggregation in whole blood was depressed in response to ADP and collagen. The animals also exhibited an initial rise followed by a fall in hematocrit level, leukocytosis, and a decrease in platelet count. These changes were detectable within hours of toxin administration, reached a maximum at 24 hr, and returned to normal over the next 2 days. Pretreatment of animals with vitamin K1 had no effect on the activity of coagulation factors. The activated partial thromboplastin time of dilutions of plasma from animals given T-2 toxin with plasma from control animals revealed a pattern which pointed to a deficiency of coagulation factors as the principal cause of prolonged clotting times in treated animals. The presence of a weak circulating anticoagulant could not be ruled out. The addition of T-2 to plasma and blood of normal animals in a concentration of 1 microgram/ml had no effect on clotting times or platelet aggregation.

Animals↗
PubMed1984

Morphological alterations in blood and bone marrow of ribavirin-treated monkeys.

The antiviral drug ribavirin (1, beta-D-ribofuranosyl-1,2,4-triazole-3-carboxamide) produced significant hematologic effects when administered to rhesus monkeys by intramuscular injection over 10 days in doses of 30 or 100 mg/kg/day. The monkeys developed dose-related progressive anemia and thrombocytosis associated with marrow erythroid hypoplasia and megakaryocyte hyperplasia. In addition, bone marrow examination revealed phagocytosis of erythroid elements by histiocytes; vacuolization of erythroid precursors, and to a lesser extent precursors of other cell types; and occasional erythroid precursors with megaloblastoid appearance. The alterations were transient and disappeared on discontinuation of the drug.

Animals↗
PubMed1984

Evaluation of the 4-pyridinemethanol WR 180,409 (enpiroline) in the treatment of induced Plasmodium falciparum infections in healthy, non-immune subjects.

WR 180,409 (enpiroline) was administered to 22 non-immune subjects infected with the multi-drug resistant Vietnam Smith isolate of Plasmodium falciparum. It was curative in single day treatment regimens with a minimum curative dose of approximately 10 mg/kg body weight. At this dose level it was well tolerated and produced rapid clearance of parasitemia in every case.

Adolescent↗
PubMed1983

False assignment of familial antithrombin III deficiency with the von Kaulla assay.

As a serum assay, the von Kaulla assay for antithrombin III has been criticized on the grounds that consumption of antithrombin III during in vitro blood clotting may lead to falsely low assay values. Use of the assay to screen a Utah pedigree for familial antithrombin III deficiency lends support to this criticism. In all, the assay was performed on 150 persons. Low values on the assay were corroborated by performing an alternative coagulation assay, an amidolytic assay, and an immunoassay. While all persons with historic evidence for a diagnosis of familial antithrombin III deficiency had low assay values, eight of 23 persons with low values had normal values on the other assays.

Adolescent↗
PubMed1983

The antithrombin III content of cryoprecipitate prepared from blood collected with and without heparin.

Antithrombin III (AT III) is a plasma protein which acts as the principal inhibitor of thrombin and is a major modulator of intravascular coagulation. Hereditary deficiency of AT III leads to recurrent episodes of thromboembolism. Acquired deficiency of AT III occurs in persons with a variety of conditions, including severe liver disease and disseminated intravascular coagulation. Replacement of AT III may be important in some deficient persons. To determine if cryoprecipitate is a useful source of AT III, we measured the AT III content of cryoprecipitate prepared from citrate phosphate dextrose blood using coagulation and fluorogenic assays and immunoassays. Using the fluorogenic assay, we also determined the effect of adding heparin to blood on the cryoprecipitation of AT III. Functional and antigenic AT III levels were similar to those of normal plasma in all citrate phosphate dextrose blood units tested, indicating that AT III is not concentrated in cryoprecipitate. Heparin had no effect on the cryoprecipitation of AT III.

Antithrombin III↗
PubMed1982

Evaluation of the antimalarial activity of the phenanthrenemethanol halofantrine (WR 171,669).

Halofantrine (WR 171,669) was administered to 27 nonimmune subjects infected with the multi-drug resistant Vietnam Smith strain of Plasmodium falciparum. It was also administered to three other subjects, one infected with the Cambodian Buchanan strain of P. falciparum, and two with blood-induced infection with the Chesson strain of P. vivax. It cured infections with all three parasites. Against the highly chloroquine-resistant Smith strain, it was curative in single day treatment regimens. The drug was well tolerated and produced rapid clearance of parasitemia in every case.

Animals↗
PubMed1981

Hodgkin disease as the terminal malignancy in Richter syndrome.

A case of Richter syndrome in which autopsy revealed typical infiltrates of Hodgkin disease, including Reed-Sternberg cells, is reported. Previous reports of this association have met with skepticism. Clinical findings in patients with Hodgkin infiltrates do not differ from those with histiocytic lymphoma, except for the more frequent occurrence of a declining lymphocyte count. The present case is further evidence that Hodgkin disease does occur as a terminal malignancy in Richter syndrome.

Autopsy↗
PubMed1980

Sideroblastic anemia as a preleukemic event in patients treated for Hodgkin's disease.

Sideroblastic anemia after treatment for Hogdkin's disease was seen in two patients 3 years after completion of radiation therapy and chemotherapy. This was followed in both by the development of myelomonoblastic leukemia. No evidence of recurrent Hodgkin's disease was present in either patient. Our observation suggests that development of sideroblastic anemia in patients previously treated for Hodgkin's disease is probably secondary to the treatment and is a preleukemic event.

Adult↗
PubMed1979

Central retinal vein occlusion in a patient with familial antithrombin III deficiency: case report.

A 60-year old man with familial antithrombin III deficiency, a primary cause of hypercoagulation, developed central retinal vein occlusion. Familial antithrombin III deficiency is inherited as an autosomal dominant condition. It is characterized by recurrent episodes of thromboembolism. The occurrence of central retinal vein occlusion in a person with familial deficiency of antithrombin III suggests the possibility of a casual relationship.

Animals↗
PubMed1978

Hyporeninemic hypoaldosteronism--case report and observation of dissociated renin and erythropoietin activity.

A case is reported of hyporeninemic hypoaldosteronism, diagnosed during an evaluation of hyperkalemia. Urine and plasma aldosterone concentrations were depressed despite hyperkalemia and were not responsive to ACTH, cosyntropin, and angiotensin 2. Adrenal glucocorticoid function was normal. Plasma renin activity also was low, and was hyporesponsive to stimulation, including intravascular volume contraction and potassium depletion. Autonomic nervous function was intact. Of the 32 previously reported cases of selective hypoaldosteronism, plasma renin activity was low in the majority of cases in which it was measured. A classification of the types of selective hypoaldosteronism is presented. It is of interest that the serum erythropoietin activity in this case was increased while plasma renin activity was markedly depressed.

Aged↗