Assessment of topical hemostats in a renal hemorrhage model in heparinized rats.

Various topical hemostatic agents or devices have been employed to address the challenges associated with hemorrhage from parenchymal organs during surgery or trauma. Their relative efficacy, however, has not been assessed in a single animal model. The objective of this study was to develop a small animal renal hemorrhage model for comparing hemostatic efficacy of various topical agents, and then to compare fibrin sealant (FS) to an existing standard of care for topical hemostasis. A left heminephrectomy was performed in anesthetized adult male Sprague-Dawley rats. Animals were anticoagulated with 2000 IU/kg heparin IV and various topical hemostatic agents were applied to the injury. Treatment groups included FS applied as a spray; FS applied through a cannula; gelatin sponge (GS) soaked in 1000 IU/mL thrombin solution; GS soaked in 300 IU/mL thrombin; dry GS; and fibrinogen without thrombin applied as a spray. The main endpoints of the study were incidence of hemostasis, blood loss, acute survival trends, and maintenance of mean arterial pressure (MAP). Three treatment groups, the two FS groups and the GS soaked in 1000 IU/mL thrombin, afforded significant hemostasis compared to the controls (P < 0.01). Both FS groups had significantly less blood loss, longer survival times, and maintained higher MAPs than the GS-treated groups. Quantitative dose effects and functional deficiencies in topical hemostatic products could be assessed using this animal model. The study demonstrated that liquid FS was significantly more efficacious than a GS soaked in thrombin for abating hemorrhage from a renal excision in a heparinized rat.

The 200- and 150-kDa neurofilament proteins react with IgG autoantibodies from chimpanzees with kuru or Creutzfeldt-Jakob disease; a 62-kDa neurofilament-associated protein reacts with sera from sheep with natural scrapie.

Sera from 46 chimpanzees with spongiform encephalopathy (18 kuru, 28 Creutzfeldt-Jakob disease) and sera from 12 sheep with natural scrapie were tested for reactivity with immunoblots of neurofilament preparations obtained from mouse brain. The sera from the chimpanzees reacted mainly with the 200- and 150-kDa proteins of the neurofilament triplet and less frequently with the 70-kDa component of the triplet and with a 62-kDa neurofilament-associated protein. In contrast, the sera of sheep with natural scrapie reacted exclusively against the 62-kDa protein. The specificity of the reactions was established by comparison of sera reactivities with those of rabbit and mouse polyclonal antibodies and mouse monoclonal antibody to neurofilament proteins.