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Polyunsaturated fatty acids (PUFAs) have significant, cardioprotective effects against ischemia. Hempseed contains a high proportion of the PUFAs linoleic acid (LA) and [alpha]-linolenic acid (ALA), which may have opposing effects on postischemic heart performance. There are no reported data concerning the cardiovascular effects of dietary hempseed intake. A group of 40 male Sprague-Dawley rats were distributed evenly into four groups that were fed for 12 wk a normal rat chow supplemented with hempseed (5% and 10%), palm oil (1%), or a 10% partially delipidated hempseed that served as a control. Plasma ALA and [gamma]-linolenic acid levels were significantly elevated in the rats that were fed a 5% or 10% hempseed-supplemented diet, but in heart tissue only ALA levels were significantly elevated in the rats fed these diets compared with control. After the dietary interventions were completed, postischemic heart performance was evaluated by measuring developed tension, resting tension, the rates of tension development and relaxation, and the number of extrasystoles. Hearts from rats fed a hempseed-supplemented diet exhibited significantly better postischemic recovery of maximal contractile function and enhanced rates of tension development and relaxation during reperfusion than hearts from the other groups. These hearts, however, were not protected from the occurrence of extrasystoles, nor were the increases in resting tension altered during ischemia or reperfusion as a function of any dietary intervention. Our data demonstrate that dietary hempseed can provide significant cardioprotective effects during postischemic reperfusion. This appears to be due to its highly enriched PUFA content. polyunsaturated fatty acid; nutrition; heart; linoleic acid; alpha linolenic acid

Small-angle neutron scattering (SANS) and viscosity measurements are used to study the mixed micellar system comprising the poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)-based triblock copolymer ([EO.sub.20])([PO.sub.70])([EO.sub.20]) and the anionic surfactant sodium dodecyl sulfate (SDS). Copolymers with high PO/EO ratios have showed an increase in the stability of the gel phase, whereas copolymers with low PO/EO ratios have showed a deterioration of the same in the presence of SDS.

Immunomagnetic separation (IMS) method is utilized to isolate biomaterials from a host fluid in which specifically selected antibodies attached to magnetic particles bind with their corresponding antigens on the surface of the target biological entities. The IMS method is found to have promising applications in microscale biosensors.

LiCl-induced changes in the micellar hydration and gelation characteristics of aqueous solutions of the two triblock copolymers F127 and P123 are analyzed by small-angle neutron scattering (SANS) and viscometry. Viscosity studies on a poly(ethylene glycol) (PEG) homopolymer with a size equivalent to that of the PEO block in F127 has shown that the dehydrating effect of the [Cl.sup.-] ion on the PEG chain is compensated by its interaction with the hydrated [Li.sup.+] ions.

Dynamic light scattering, small-angle neutron scattering, and viscosity studies are carried out to examine the influence of NaCl and ethanol on the structure of triblock copolymer [(EO)(sub 20)(PO)(sub 70)-(EO)(sub 20) micelles in aqueous medium. The presence of small amount of ethanol induces a sphere to rod transition of micelles at high temperatures, while the pure triblock copolymer solutions do not show any significant growth of the micelles on approaching the cloud point.