Search PubMed⌕ Search

Biomedical subjects

H M Rinder

Publications and source records attributed to H M Rinder.

45 records · Page 3Linked to original sources

In vitro and in vivo evaluation of platelet transfusions administered through an electromechanical infusion pump.

The authors evaluated two platelet infusion pump systems, the Abbott Lifecare 5000 and the Omniflow 4000, for evidence of in vitro platelet damage and in vivo platelet recovery. When compared with gravity infusion, there was no significant difference in levels of LDH discharge, beta-thromboglobulin release, cell counts, or morphology score after platelet concentrates were infused through these pumps. When the pumps were compared to gravity infusion in thrombocytopenic oncology patients, no differences were noted in platelet-corrected count increments at 1-4 hours or 12-24 hours post-transfusion. The authors conclude that these infusion systems do not significantly injure or activate platelets and that they are efficacious for transfusing platelet concentrates to thrombocytopenic patients. These infusion pumps may be of clinical benefit to pediatric or adult patients with a history of prior transfusion reactions, when precise control of the rate and volume of platelet transfusion is desired.

Blood Platelets↗

Correlated measurement of platelet release and aggregation in whole blood.

We have used a technique for the simultaneous measurement of platelet activation and aggregation in whole blood using two-color immunofluorescence and flow cytometry to study the relationship between the release reaction and aggregation. A monoclonal antibody specific for the alpha granule membrane protein GMP-140 was used to measure the release reaction, and a monoclonal antibody specific for platelet membrane glycoprotein Ib (GPIb) was used to identify platelets and platelet aggregates. Aggregates were identified as particles expressing both levels of GPIb and size larger than that of resting single platelets. Anticoagulated whole blood was incubated with platelet agonists. At various times samples of the blood were removed and immediately fixed with paraformaldehyde. Blood that had been anticoagulated with ethylenediamine tetraacetic acid showed progressive release of platelets but little or no aggregation. However, blood anticoagulated with citrate or heparin showed correlated release and aggregation. The degree of aggregation was greater in heparin than in citrate. The expression of GPIb and GMP-140 increased in direct proportion to the size of the aggregates. Aggregates were observed varying in apparent diameter up to approximately 20 microns. During prolonged incubation there was progressive disaggregation of adenosine diphosphate (ADP)-induced aggregates. After disaggregation the proportion of GMP-140 negative single platelets increased, indicating that both released and nonreleased platelets participated in the aggregation. There was little or no disaggregation of phorbol myristate acetate (PMA)-induced aggregates. The relatively small size and reversibility of platelet aggregates that we have observed in whole blood may be relevant to phenomena occurring in vivo and in extracorporeal circulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗

Impact of unusual gastrointestinal problems on the treatment of tricyclic antidepressant overdose.

We report the cases of two patients with tricyclic antidepressant overdose in which the use of charcoal was hampered by gastrointestinal abnormalities. In the first patient, a previous gastric bypass procedure impeded the placement of an orogastric tube and subsequent charcoal administration, while potentially facilitating rapid absorption of the drug--factors that may have contributed to her death. In the second patient, severe esophageal spasm delayed therapy until IV nitroglycerin relieved the functional obstruction. Both circumstances are previously unreported complications associated with tricyclic antidepressant overdose. Potentially corrective measures are proposed.

Adult↗

Survival in complicated diphenhydramine overdose.

This report describes the first case of an adult to survive all the major complications of diphenhydramine hydrochloride overdose, including hyperpyrexia, status epilepticus, coma, and cardiac arrhythmias. Physostigmine appeared to be of benefit in reversing these abnormalities in combination with other therapies.

Adult↗

Septic anaerobic jugular phlebitis with pulmonary embolism: problems in management.

Anaerobic gram-negative bacillary bacteremia and multiple septic pulmonary emboli developed rapidly in two previously healthy young men after an episode of pharyngitis. One patient developed proptosis and subsequent uniocular blindness. In both cases facial swelling was an early sign of jugular vein involvement. In patients not responding to antibiotic therapy, systemic anticoagulation or surgical venous ligation may be potentially useful as an additional therapeutic measure. Septic jugular vein phlebitis is a serious condition that requires early recognition and rapid institution of appropriate therapy.

Adult↗

Platelet function testing by flow cytometry.

The availability of fluorescent monoclonal antibodies and probes now provides a powerful tool for examining platelet function by flow cytometry. These techniques cna be employed to determine the resting and stimulated expression of platelet glycoprotein receptors, the activation status of platelets assessed by secretion of granule contents (including expression of activation-dependent neoantigens), adhesion ligand binding to platelets, and intracellular calcium flux after exposure of platelets to agonist. In addition, flow cytometry has now been used to study the functional properties of stimulated platelets, including microparticle generation, platelet aggregation, and platelet-heterotypic cell conjugate formation. This brief review is presented as a general outline of the literature that uses flow cytometric methodology to examine in vivo and ex vivo platelet function.

Blood Platelet Disorders↗