The increasing demand for laboratory-reared argasid and ixodid ticks for research and control purposes makes it necessary to develop effective and standardized tick feeding methods without using live animals as hosts. The in vitro maintenance technique, described in this paper, has been used successfully for rearing Ornithodoros moubata moubata by ...

Studies were made to compare completely heparin-bonded (HBS) and conventional extracorporeal circulation surfaces using capillary membrane oxygenators (CMO) in sheep and dogs for up to five days. The aims were: to investigate the need for systemic heparinization in the case of heparin-coated surfaces, to assess blood compatibility and gas exchange ...

The dynamic fluctuation of thrombin-antithrombin III complex (TAT) was studied in blood obtained during the daytime (at 9 AM, noon, 3 PM), during extracorporeal circulation and during the course of disseminated intravascular coagulation (DIC), to certify whether the level of TAT in blood can reflect the generation of thrombin. In ...

A blind, randomized study of the effects of a heparin-coated bypass circuit on thromboembolus formation and hematologic and hemostatic parameters was carried out on 12 dogs. The dogs were anesthetized and bypassed for 24 hours using a centrifugal pump circuit with a mean flow of 475 ml/minute. Six of the ...

By analyzing whole blood containing no anticoagulants (uncoagulated whole blood) immediately after collection, we evaluated the relative changes in the concentrations of ionized calcium and other electrolytes in whole blood collected in dry heparinized syringes and in serum prepared from blood collected in evacuated blood-collection tubes. Using these dry heparinized ...

Thrombus forms on catheters and other indwelling synthetic materials. Systemic heparin infusion decreases, but does not eliminate thrombus formation. The day is approaching when systemic heparinization may no longer be indicated to suppress catheter thrombogenesis. Passivation of catheters by heparin immobilization is not yet perfected, but progress is being made. ...

Some investigation in this laboratory pointed to an unexpectedly slow inhibition of cholinesterase by D-tubocurarine, occurring in addition to a typically instantaneous inhibition. In order to elucidate this phenomenon, the hydrolysis of butyrylthiocholine catalyzed by cholinesterase was recorded, in the absence and presence of D-tubocurarine, on a stopped-flow apparatus. Experimental ...

We studied the incidence of cerebral hemorrhage in an animal model of embolic stroke to determine the safety of aspirin, heparin, and tissue plasminogen activator therapies. We occluded the middle cerebral arteries of rabbits with labeled blood clots and administered either tissue plasminogen activator, heparin, aspirin, tissue plasminogen activator plus ...

We report a new and reproducible model of thrombosis in the rat femoral artery. The thrombosis is initiated by endothelial injury subsequent to photochemical reaction between systemically injected rose bengal (10 mg/kg, i.v.) and transillumination of filtered xenon lamp (wave length: 540 nm) from the outside of the vessel. The ...

Blood specimens from the retro-orbital sinus of 80 Sprague Dawley rats were collected into tubes containing lithium heparin either as a solid or an aqueous solution. Plasma was separated for blood chemistry analysis. Twenty-eight blood specimens collected into tubes containing solid heparin were clotted and eight specimens were partially clotted ...

The purpose of this quasi-experimental study was to determine if the patency of the peripheral intermittent intravenous device (PIID) would be maintained as effectively with a sodium chloride solution as with a dilute heparin solution and to determine if a sodium chloride solution could be used with fewer local complications ...

Red blood cells (pRBC) collected in citrate, phosphate, dextrose, adenine-formula 1 (CPDA-1) and citrate, phosphate, dextrose-adenine, manitol saline solution (CPD-ADSOL [AS-1]) anticoagulants are increasingly being stored for variable periods in transfusion service inventories following irradiation. While anecdotal reports of increased K+ following irradiation and storage have recently appeared in the ...

Whole blood activated clotting time (ACT) can be determined by many different methods that use a variety of clotting cascade activators and end-points. This study compared the results of three whole blood ACT instruments at equivalent concentrations of heparin. Whole blood (9.8 ml) from 10 healthy adult volunteers without coagulation ...

The monitoring of heparin anticoagulation is fraught with difficulties because of the need for repetitive venipunctures and the vagaries of sample handling and processing. The authors evaluated a new aPTT monitoring system with the potential to eliminate many of these difficulties. The Ciba Corning Diagnostics 512 Coagulation Monitor (CCD monitor) ...

Six male healthy volunteers were given single oral doses of 7.5 mg/kg of metrifonate and concentrations of metrifonate and dichlorvos were determined in whole blood using a standardized sampling procedure. Blood was collected in test tubes containing equal volumes of 0.74 M phosphoric acid for the determinations of metrifonate and ...

Clinical application of heparin-coated cardiopulmonary bypass equipment during perfusion with low systemic heparinization is reported with special emphasis on patients refusing any transfusion of homologous blood or blood products. Using the described technique, coronary artery revascularization was successfully performed in three Jehovah's witnesses. During perfusion, the activated clotting time (ACT) ...

Blood cell trauma and postoperative bleeding remain important problems in cardiopulmonary bypass (CPB). We compared heparin-coated with non-coated circuits in the pig. Twenty animals were perfused for 2 h at normothermia using membrane oxygenators (Bentley Bos 50). Two groups were studied. In the non-coated group (NC, n = 11) the ...

The dose- and time-dependent antithrombotic activity of recombinant hirudin (r-hirudin) was examined in a new animal model of venous thrombosis. For the evaluation of the antithrombotic activity of r-hirudin, an occluding thrombus was produced by repeated clamping of the rat jugular vein. The number of clampings necessary to induce thrombosis ...

Heparinization of blood inhibited the generation of fibrinopeptide A (FPA) after addition of thromboplastin (TP). Heparinization was more effective when performed in vivo than in vitro; the amounts of FPA at 60 s incubation were 8% and 32%, respectively, of control values in nonheparinized blood. When monospecific, neutralizing IgG against ...

Although acetylcholinesterase is the target molecule of organophosphate poisoning, it is not always assayed in clinical evaluations which include only the determination of plasma or serum cholinesterase. In this paper we present observations on workers exposed to, or poisoned by, ethylparathion. Acetylcholinesterase decreased earlier and more intensely than cholinesterase, with ...

It is known that the anticoagulant effect of blood or plasma is greater when heparin is given in vivo than when added in similar heparin concentrations in vitro. In this study, we neutralized heparin in citrated blood with polybrene, and then triggered coagulation with dilute tissue thromboplastin (TTP) and CaCl2. ...

To investigate the local effect of heparin on blood clot formation and partial thromboplastin time (PTT), blood was withdrawn into the catheters filled with iopamidol and heparin at 0, 1, 2, 3, 5, and 10 U per ml concentrations as debubbling. After 30 min incubation, blood clotting was observed in ...

A high level of heparin, infused into blood, often causes severe complications such as hemorrhage, especially when a drug is administered over a long period. The most common way of preventing a patient from bleeding after transfusion is by administering a heparin antagonist such as protamine. The complex molecules formed ...

When extracorporeal blood circulation (ECBC) is used, systemic heparinization is necessary to prevent clotting of the blood in the extracorporeal circuit. However, the high circulating heparin concentration needed often leads to bleeding complications. To avoid these, protamine, a heparin antagonist, is administered at the conclusion of the ECBC procedure to ...

We studied hemocompatibility of various blood tubings with C3a anaphylatoxin measurement and comparative electron scanning microscopy. The following tubing materials were tested: polyvinylchloride (PVC) plasticised with phthalate (PVC), pvc plasticised with phthalate coextruded with polyurethane (PIV), and two phthalate-free lines: pvc plasticised with trimellitate coextruded with polyurethane (TRI) and pvc ...

In this paper we address the question of whether balloon angioplasty induces thrombin action. In the studies reported here we measured fibrinopeptide A levels in a group of atherosclerotic monkeys undergoing coronary angioplasty. A blood collection catheter was introduced into the inferior vena cava through a femoral vein, and the ...

A heparin coated cardiopulmonary bypass system was evaluated for canine veno-venous extracorporeal membrane oxygenation (ECMO). The ECMO system consisted of a hollow fiber membrane oxygenator and pediatric centrifugal pump but no reservoir. In Group 1 (N = 6), the ECMO system was coated with a covalent, heparin-binding method, except for ...

The ability of DEAE-cellulose (Hemophan) membranes to bind heparin may reduce bioavailable heparin and predispose to dialyzer clotting, thus preventing use of Hemophan with low-dose heparin. To examine this possibility, residual blood volumes were determined following 95 treatments with dialyzers containing Hemophan membranes in 11 patients. No heparin was added ...

Ten collaborating laboratories assayed 4 blind duplicate pairs of whole bovine blood for cholinesterase activity. The 4 sample pairs ranged from normal (100%) to severely organo-phosphorus-inhibited (less than 10%) activity. Collaborators also received commercially available human lyophillized serum as an external control and a chromate solution to evaluate spectrophotometer performance. ...

Adherence of chicken heterophils was evaluated at 37 C using preconstructed columns containing various weights of nylon fiber (75 mg, 100 mg, or 125 mg) and whole blood anticoagulated with sodium heparin or 10% disodium ethylenediamine tetraacetic acid (EDTA). Additionally, 50-mg and 75-mg nylon fiber columns incubated at 41 C ...

Non-heparin hemodialysis (HD) was successfully done in anuric dogs with the oral administration of a newly developed antiplatelet agent, 4-cyano-5,5-bis(4-methoxyphenyl)-4-pentenoic acid, (E5510, Eisai Pharmaceutical Co., Japan). In the current study, the antithrombotic effect of E5510 during HD was investigated. Eleven mongrel dogs with bilateral ureteral ligation were given 0.1 mg/kg ...

The patency-rate of venous bypasses depends - beside other important factors - upon the integrity of the transplanted vessel, especially on the condition of the tunica intima. Under this aspect we examined by light microscopy a total of over 1100 slices of human as well as animal vein-segments which had ...

We recently evaluated the Reflotron Total Cholesterol dry chemistry assay by examining the calibration and the accuracy of the assay in serum, whole venous EDTA-blood and capillary EDTA blood. We now describe a study on the analysis in heparinized venous and heparinized finger stick blood. Cholesterol assays in venous serum ...

Blood samples from 12 pregnant does were collected in flasks containing heparin. Each sample was divided into 31 aliquots, the first of which was immediately centrifuged for plasma separation. Fifteen of the remaining aliquots from each goat were kept at 17 degrees C, while the remaining is were refrigerated at ...

Device-induced thrombogenesis was studied in an in vitro model using human blood circulated through an artificial ventricle. A new constant pressure filtration technique was used to detect circulating microemboli, the activated partial thromboplastin time (APTT) test was used to monitor the blood for the presence of anticoagulant activity of heparin, ...

Human blood was injected into angiographic catheters filled with contrast media or flushing media. The catheters were allowed to stand at 37 degrees C for 10, 20 or 30 min. Physiologic saline was then injected through the catheters, the catheter contents were shaken and filtered, and any clots were identified. ...

An in vitro heparin release of lipoprotein lipase (LPL) from whole blood, mainly from monocytes, was demonstrated by (1) the time-course of lipolytic activity with the presence of 10 U/ml heparin at 37 degrees C, (2) the distribution of LPL activity in monocyte and lymphocyte fractions, (3) an immuno-inactivation with ...

The effect of calcium-balanced heparin (471896, CIBA CORNING) on blood gas and electrolyte analysis was evaluated, by comparing with that of sodium heparin (Na heparin). One ml of whole blood was collected into a syringe, which contained calcium-balance heparin (Ca balanced heparin) or Na heparin. 122 pairs of blood samples ...

In assigning values to fresh blood specimens used for calibrating automated blood cell analysers, haemoglobin concentration should be determined by the ICSH recommended hemiglobincyanide (HiCN) method. Errors in the reference method may be caused by inadequate blood collection, e.g. incorrect anticoagulation; inadequate dilution, e.g. use of inadequately calibrated pipettes; incomplete ...

Anion exchange resin fiber (Ionex) was used as a heparin adsorbent. Ionex has the adsorption capacity of 70 mg/g (weight by desiccation) for heparin, and was used in an attempt to remove the heparin from blood-perfused artificial organs, before the blood was transfused back into the patients. In the ex ...

Heparin is the anticoagulant used during cardiopulmonary bypass (CPB). Both the use of heparin and the reversal of its effect with protamine have well-documented complications. Ancrod is a defibrinogenating enzyme that has been used as an anticoagulant in humans, but its use as an anticoagulant for CPB has been limited ...

Standard heparin (SH) is frequently used in the sick neonate to prevent catheter related thrombosis. SH can cause significant bleeding complications in the adult and its use in the neonate is linked to an increased incidence of intraventricular hemorrhage. Recently available low molecular weight heparins (LMWH) offer potential advantages over ...

The hydraulic conductivity of solutions of Swarm rat chondrosarcoma proteoglycan subunit and of chondroitin 4- and 6-sulfate up to concentrations of 80 mg ml-1 have been measured under physiological conditions using sedimentation velocity and membrane ultrafiltration techniques. This study establishes the very high flow resistance of the proteoglycan and that ...

Thrombin activity reflected by increased plasma concentrations in vivo of fibrinopeptide A (FPA) increases when streptokinase (SK) is administered to patients with acute myocardial infarction. Although procoagulant effects have been found in vitro, the use of anticoagulated plasma limits the extent to which the phenomena observed can be viewed to ...

Performance characteristics of heparin-coated hollow-fiber membrane oxygenators (COATED HFMO, n = 5) were evaluated in an open-chest dog model without systemic heparinization. Four other oxygenators were evaluated with standard systemic heparinization (300 IU/kg, activated clotting time more than 400 seconds): a standard hollow-fiber membrane oxygenator (HFMO, n = 5), an ...

The low in vitro thrombogenicity of polyacrylonitrile (AN-69) membrane may offer the possibility of performing hemodialysis (HD) with little or no heparin. The authors sought to reduce heparin dosage using AN-69 dialyzers at blood flows of 400 to 600 ml/min. Over a 90 day period, 2228 HDs were performed: 1531 ...

As already shown, a single bolus injection of heparin is sufficient to perform extracorporeal circulation (ECC) for long-term lung support if bioactive surfaces (HBS) are used. In the present study whether complete avoidance of systemic heparinization using HBS is possible was studied. Seven conscious sheep (50-60 kg) underwent venovenous bypass ...

A new heparinized hydrophilic polymer (Anthron) which contains a large amount of heparin ionically bound to the polymer matrix has been developed. Anthron showed excellent and long-term blood compatibility both in animal and clinical tests. It has been clarified that the long-term blood compatibility of Anthron results from its negative ...

Arterial blood gas analysis was performed utilizing different heparin volumes and concentrations on 20 umbilical cord blood samples. A significant decrease in the bicarbonate concentration and base excess was found when 10,000 instead of 1,000 U/mL heparin was used to coat the syringe. When 0.2 mL of 1,000 U/mL heparin ...

Veno-venous bypass without the use of systemic heparinization has recently become of increasing interest for application during liver transplantation and surgery on the large abdominal veins. However, possible adverse effects on blood components as demonstrated by means of hematologic and hemostatic parameters or on the occurrence of thromboembolic complications are ...