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J L Tullis

Publications and source records attributed to J L Tullis.

At least 19 recordsLinked to original sources
PubMed1996

Infusible platelet membrane microvesicles: a potential transfusion substitute for platelets.

BACKGROUND: Several substitutes for intact, viable platelets have been used for transfusion, both to people and in animal models, with varied success. Infusible platelet membrane (IPM) is prepared from human platelets. IPM retains the glycoprotein (GP)lb receptor and has platelet factor 3 activity (procoagulant activity). However, factor V, serotonin, a cytoplasmic marker enzyme (purine nucleotide phosphorylase), GPIIb/IIIa complex, and HLA class I and II antigens are all absent in IPM. STUDY DESIGN AND METHODS: IPM is prepared from outdated platelets. The platelets were disrupted by freezing and thawing; they were washed and heated to inactivate possible viral contaminants, and then the sonicated membrane microvesicle fraction was separated and lyophilized. The hemostatic activity of IPM was measured by its ability to reduce the prolonged bleeding time in thrombocytopenic rabbits. RESULTS: Administration of IPM at a dose of 2 mg per kg results in a substantial reduction in the bleeding time. In a series of 23 experiments, a median preinjection bleeding time of 15 minutes was reduced to 6 minutes within 4 hours after IPM administration. Administration of IPM did show a mild enhancement in the thrombogenicity index, as measured in the Wessler rabbit model. This enhancement is, however, not significant, as a thrombogenicity index value of up to 0.6 is clinically acceptable. CONCLUSION: IPM may have clinical potential as a substitute for platelets in the treatment of bleeding due to thrombocytopenia.

Animals↗
PubMed1987

Platelet antithrombin defect in malignancy: platelet protein alterations.

Sixty-eight patients with malignant disease were divided into two groups based on the results of the platelet antithrombin test (PAT). The normal group had a PAT clotting time ranging from 21.4 to 29.8 seconds, which was equivalent to 25% to 65% inactivation of the 2 U of thrombin added to the test system. The other group showed abnormal PAT clotting time, less than 21.4 seconds or less than 25% thrombin inactivation. The polypeptide composition of platelets from the two patient groups was analyzed by sodium dodecyl sulfate (SDS)-electrophoresis on 7.5% polyacrylamide gels. A polypeptide of 180,000 apparent mol wt was decreased or absent in both Coomassie blue- and Alcian blue-stained gels of the platelets from patients whose PAT was abnormal; this polypeptide comigrated with purified platelet thrombospondin. Tritium labeling of platelet surface glycoproteins by the periodate-borohydride method followed by two-dimensional electrophoresis was performed on platelets of seven patients with abnormal PAT. When they were compared with ten patients with normal PAT, a glycoprotein of 140,000 apparent mol wt with a pl of 4.5 to 5.2 was decreased in platelets of all seven patients with abnormal PAT. Nitrocellulose replicas of one-dimensional gels of platelets from 13 of 14 patients with abnormal PAT showed decreased reaction with an anti-human platelet glycocalicin antiserum. Platelets of these same patients also showed a decreased or absent platelet agglutination induced by ristocetin. Patients with normal PAT had a mean agglutination slope of 1.25 +/- 0.6 (n = 26) as compared with 0.37 +/- 0.34 (n = 26) for the abnormal PAT group (P less than .001). Results indicate that platelets from a subpopulation of tumor patients characterized by decreased platelet antithrombin activity have alterations in two platelet glycoproteins, identified as GPIb and thrombospondin.

Antithrombins↗
PubMed1982

Alteration in plasma proteins and platelet functions with aging and cigarette smoking in healthy men.

Blood samples were obtained on four different occasions from 18 cigarette smoking and 34 non-smoking healthy men (age 40-69) and analyzed to assess age- and smoking-associated changes in plasma proteins, blood coagulation and platelet functions. Collagen-induced platelet aggregation was significantly increased with aging in non-smokers. Significant changes in chronic smokers were increases in platelet count and fibrinogen in plasma; elevation of platelet factor-3 (PF-3) activity in platelet-poor plasma (PPP); increase in serum levels of alpha 1-antitrypsin, orosomucoid, haptoglobin and properdin factor B; and shortening of the lag period of collagen-induced platelet aggregation. Filtration of PPP through Millipore filters removed PF-3 membranes. The differences in PF-3 activities in filtered plasma were no longer significant between smokers and non-smokers. Results suggest that chronic smokers have higher levels of acute phase proteins reflecting underlying inflammatory processes, and higher levels of PF-3 activity in plasma due to liberation of PF-3 membranes from platelets.

Adult↗
PubMed1981

Thrombin inhibition by malignant and normal cells: a cell-bound antithrombin effect.

Analysis of fresh surgical specimens of normal tissue and tumor tissue show a cellular antithrombin activity to be present in certain organs. In normal tissues it was noted chiefly in normal colon, testes, breast, and uterus. In malignant tissues it was prominent in adenocarcinomas of the colon, breast, and lung. No epidermoid tumors showed evidence of thrombin binding. The thrombin- binding activity required the presence of intact cells and was distinct from the soluble antithrombins normally present in plasma and serum. There is growing evidence to suggest an interrelationship between clotting and the growth and dissemination of cancer. The implications of cellular antithrombins are reviewed in this context.

Adenocarcinoma↗
PubMed1981

Antithrombin III profiles in malignancy, relationship primary tumors and metastatic sites.

Variations of antithrombin III were studied in a non-randomized population of consecutive cancer cases admitted to a referral hospital. Differences between functional and immunologic assay were observed. Decreases were observed in both assays when compared to a population of hospitalized controls. Patients with cancer of the colon, ovary and prostate showed a deficiency of antithrombin III more frequently than other common tumors. When all tumor cases were subdivided into those in remission compared to those with metastases, a significant decrease in antithrombin III also could be shown. Metastases to the liver were strikingly common in cancer patients with decreased antithrombin III. In these patients, the decrease in antithrombin III could be statistically correlated with reduction in serum albumin.

Antithrombin III↗
PubMed1979

L-asparaginase effect on antithrombin-III levels.

The effect of L-asparaginase (L-asp) therapy on circulating antithrombin-III (AT-III) was monitored in three patients with acute lymphoblastic leukemia. Serial determination for AT-III by both a functional assay and an immunologic assay demonstrated a rapid decrease in serum AT-III levels, followed by a protracted recovery beyond the period of L-asp exposure. One of the three patients developed a reversible venous thrombosis of the arm. The mechanism of the L-asparaginase effect may be related to peripheral degradation of AT-III or to inhibition of production.

Adult↗
PubMed1978

Intraaterial hepatic infusion and intravenous adriamycin for treatment of hepatocellular carcinoma: a clinical and pharmacology report.

Four patients received intraarterial (ia) hepatic infusion and 10 received intravenous (iv) adriamycin for hepatocellular carcinoma. Four of each group are evaluable. The remaining 6 patients died within 14 days of intravenous therapy and are, therefore, considered nonevaluable. Patients received 2 to 9 courses of adriamycin every 3 weeks. One half of each group of evaluable patients had partial responses (pr). The group had pr for 22.5 weeks (range 8 to 37). The iv group had pr 27.2 weeks (range: 16 to 38.5). Mean survival was 21 weeks for nonresponders, and 43 weeks for responders. Intraarterial infusion did not protect patients from adriamycin toxicity. Cardiac and liver toxicity were not seen, but marrow and gastrointestinal toxicity developed at 1.2 X 10(-7)M adriamycin serum level. Adriamycin disappearance curves after ia and iv therapy were similar for similar bilirubin levels, and prolonged with hyperbilirubinemia. Ascites fluid did not accumulate detectable adriamycin. Pharmacokinetics are described in this report.

Adolescent↗
PubMed1978

Platelet antithrombin deficiency: a new clinical entity.

A kindred with a history of multiple thromboses was studied for coagulant abnormalities. A deficiency of serum antithrombin III was found in approximately half of the 13 family members by either coagulant or immunologic assay. No clear relationship between antithrombin III deficiency and a history of thrombosis was present. Platelet antithrombin assays were also studied in the same subjects. Ten of the 13 members were deficient. None of the remaining three had a history of thrombosis. On the basis of these findings, the hypothesis is proposed that in some cases familial hypercoagulability may be due to a platelet antithrombin deficiency and that the serum antithrombin III deficiency in some cases is a secondary rather than a primary effect.

Adolescent↗
PubMed1978

Ristocetin precipitation test: a new simple test for detection of fibrin monomer and fibrin degradation products.

The ristocetin precipitation test was designed as a simplified test to detect fibrin monomers and fibrinogen/fibrin degradation products (FPD/fdp). The ristocetin precipitation test is positive in plasma samples containing either fibrin monomer (greater than 5--10 microgram/ml) or early fdp (greater than 50--100 microgram/ml). The ristocetin precipitation test is negative in plasma with fibrinogen concentrations to 1,000 mg/dl or fibrinogen degradation products FDP) and late fdp to 400 microgram/ml. The ristocetin precipitation test is positive in plasmas collected from rabbits after the infusion of thrombin (2.7 u/kg) or thrombin and streptokinase (10,000 u/kg); the test is negative in plasmas from animals treated with streptokinase or saline solution alone. The ristocetin precipitation test is negative in normal human plasmas and plasmas from patients who have primary firbinogenolysis, but positive in plasmas from patients with disseminated intravascular coagulation. These results suggest that the restocetin precipitation test can be a useful test for the detection of plasma fibrin monomers and early fdp.

Animals↗
PubMed1978

Plateletpheresis by discontinuous centrifugation: effect of collecting methods on the in vitro function of platelets.

The in vitro function of platelets collected by two different methods during centrifugal plateletpheresis was compared. The RBC method involves collecting platelets with red cells followed by a supplementary spin to remove them, whereas the no-RBC method requires collecting platelets only from the buffy coat without red cells. Platelet response to adenosine diphosphate (ADP), epinephrine and collagen was slightly reduced in platelet-rich plasma (PRP) prepared by no-RBC technique and was markedly decreased in samples obtained by the RBC technique when compared to prepheresis controls. The decrease in platelet response to ADP, epinephrine and collagen was apparent in three testing systems: aggregation, release of serotonin and reptilase clot retraction. Both plasma and platelets appeared to be affected by the pheresis procedure. Platelet preparations obtained by both RBC and no-RBC techniques showed an increase of platelet factor 3 activity and an enhancement of aggregation, release of serotonin and clot retraction induced by thrombin as compared to prepheresis controls. Postpheresis platelet-poor plasma contains platelet membrane fragments which exhibit a high platelet factor 3 activity. The results showed that the RBC method, although providing a higher platelet yield, caused more qualitative alterations in platelets than in those obtained by no-RBC method, and that both methods of collecting platelets activated the procoagulant activity of platelets.

Blood Platelets↗
PubMed1977

Annual discourse--don't eat the quails.

Physicians were the first individuals recorded by name in history. Their attempts to define disease influenced fundamentally the cultures and religions of the world. Surgical skills, although highly developed in ancient times, appear to have been less well documented historically than medical disorders. Because of the greater threat to survival that diseases posed, they became incorporated into religious customs. Contagious diseases also influenced greatly the laws, traditions and historical events of the Bible. Leprosy provided a physical example that presumably represented an image of sin, but it probably was no more prevalent as a disease during Biblical times than at present. Many of the Biblical stories assumed to be allegorical may have been founded on medical fact. For example, it appears likely that the quails that poisoned the wandering Jews were contaminated with cyanide.

Animals↗