Mobile Stroke Unit Reduces Time to Image Acquisition and Reporting

Timely administration of thrombolytic therapy is critical to maximizing the likelihood of favorable outcomes in patients with acute ischemic stroke. Although emergency medical service activation overall improves the timeliness of acute stroke treatment, the time from emergency medical service dispatch to hospital arrival unavoidably decreases the timeliness of thrombolytic administration. Our mobile stroke unit, a new-generation ambulance with on-board CT scanning capability, reduces key imaging time metrics and facilitates in-the-field delivery of IV thrombolytic therapy.

Recombinant human platelet-activating factor acetylhydrolase reduces the frequency of diabetes in the diabetes-prone BB rat

Platelet-activating factor (PAF) has been implicated in the development of type 1 diabetes. Our previous studies have suggested that PAF inhibitors reduce insulitis and the frequency of diabetes in BB rats. In this study, serum PAF levels were reduced to address the hypothesis that PAF is important for the development of insulitis. From the age of 35 days on, DP-BB rats were treated with human recombinant PAF acetylhydrolase (rPAF-AH), which efficiently inactivates PAF. Our data indicate that intraperitoneal injections of rPAF-AH reduce the incidence of diabetes in the DP-BB rat. Daily intraperitoneal injections of 6.0 mg/kg body wt rPAF-AH reduced the frequency of diabetes in saline-injected rats from 90% (27/30) to 57% (17/30) (P = 0.004). As found by morphometric analysis on pancreatic islets, DP-BB rats protected from diabetes had less severe degrees of insulitis in a dose-dependent manner. DP-BB rats protected by rPAF-AH also had a higher percentage of insulin-positive cells in pancreas sections compared with those from diabetic animals. We therefore speculated that the beta-cells were protected from insulitis by rPAF-AH.

Anti-inflammatory properties of a platelet-activating factor acetylhydrolase

Platelet-activating factor (PAF) is a potent pro-inflammatory phospholipid that activates cells involved in inflammation. The biological activity of PAF depends on its structural features, namely an ether linkage at the sn-1 position and an acetate group at the sn-2 position. The actions of PAF are abolished by hydrolysis of the acetyl residue, a reaction catalysed by PAF acetylhydrolase. There are at least two forms of this enzyme--one intracellular and another that circulates in plasma and is likely to regulate inflammation. Here we report the molecular cloning and characterization of the human plasma PAF acetylhydrolase. The unique sequence contains a Gly-Xaa-Ser-Xaa-Gly motif commonly found in lipases. Recombinant PAF acetylhydrolase has the substrate specificity and lipoprotein association of the native enzyme, and blocks inflammation in vivo: it markedly decreases vascular leakage in pleurisy and paw oedema, suggesting that PAF acetylhydrolase might be a useful therapy for severe acute inflammation.