Construction and expression of a hybrid plasminogen activator gene with sequences from non-protease region of tissue-type plasminogen activator (t-PA) and protease region of urokinase (u-PA)

There are two physiological plasminogen activators (PAs), tissue-type PA (t-PA) and urokinase (u-PA) which possess distinct immunological and biochemical characteristics. Using genetic engineering techniques a hybrid t:u-PA cDNA, comprised of amino acid (aa) sequences corresponding to the non-protease region (aa 1-261) of t-PA and the protease region (aa 132-411) of u-PA, was constructed. The t:u-PA gene after insertion into the SV40 expression vector was expressed in monkey Cos-1 cells. The 66-67 kDa t:u-PA was produced in an enzymatically active form. The fibrinolytic activity of the t:u-PA could be quenched by anti-urokinase as well as by anti-t-PA sera. Like urokinase, the t:u-PA showed a high intrinsic plasminogen activation. This activity, as in the case of t-PA, was stimulated by fibrin. The u-PA, on the other hand, stimulated plasminogen activation marginally in the presence of fibrin. Both the t:u-PA and t-PA showed binding affinity for fibrin clot. This study strongly suggests the autonomous nature of the structural domains in PA and also demonstrates the feasibility of shuffling these domains without loss of their functional activities.

An automated procedure for the study of perceptual imprinting

A new procedure and automated apparatus for the study of approach-withdrawal behavior and associated perceptual learning in young precocial animals are presented. The construction and functions of the apparatus are discussed in detail.

Safe handling of hazardous drugs

Background: This evidence-based practice guideline was developed to update and address new issues in the handling of hazardous drugs including being compliant with NAPRA (National Association of Pharmacy Regulatory Authorities) and USP 800 (United States Pharmacopeia) standards, the use of personal protective equipment and treatment in diverse settings including in the home setting. Methods: This guideline was developed from an adaptation and endorsement of existing guidelines and from three systematic reviews. Prior to publication, this guideline underwent a series of peer, patient, methodological and external reviews to gather feedback. All comments were addressed and the guideline was amended when required. This guideline applies to and is intended for all health care workers who may come into contact with hazardous drugs at any point in the medication circuit. Results: The recommendations represent a reasonable and practical set of procedures that the intended users of this guideline should implement to minimize the opportunity for accidental exposure. These recommendations are not limited to just the point of care, but cover the entire chain of handling of cytotoxics from the time they enter the institution until they leave in the patient or as waste. Conclusions: Decreasing the likelihood of accidental exposure to cytotoxic agents within the medication circuit is the main objective of this evidenced-based guideline. The recommendations differ slightly from previous guidelines due to new evidence.