A survey of 65 populations of Colorado potato beetle, Leptinotarsa decemlineata (Say), from locations across Prince Edward Island in 1993 indicated that insecticide resistance was widespread, but was most prevalent in the western and central potato-producing areas. Of the populations surveyed, 31, 26, 19, and 4% were classified as resistant to permethrin, carbofuran, azinphos-methyl, and endosulfan, respectively. Of 53 populations surveyed for resistance to these four insecticides, 13, six, four, and one of the populations were classified as resistant to one, two, three, and four insecticides, respectively.

The therapeutic mechanism of mesenchymal stromal/stem cells (MSC) for the treatment of acute myocardial infarction is not well understood. Our goal was to get insights into this mechanism by analyzing the survival kinetics of allogeneic and syngeneic cell transplants under different tissue conditions. Two MSC cell banks, stably and equally expressing the luciferase reporter construct, were developed for these studies and injected directly to the myocardium of Lewis rat recipients under syngeneic or allogeneic transplantation conditions. Cell survival was monitored by real-time fashion for up to 2 weeks, using optical imaging device (IVIS, Xenogen Corp.). We found that both syngeneic and allogeneic grafts reduced significantly in size during the first week of transplantation, either in the normal or in the late infarcted heart (5 days after MI) and allotransplants became always smaller than syngeneic grafts during this period. Low dose of cyclosporine A treatment had a benefit on both allo- and syngeneic graft sizes, suggesting that multiple mechanisms play a role in early graft reduction. The MSC characteristic factors IL-6, IL-8, MCP-1, and VEGF were well above the control level in the heart tissue at 4 days after cell injection, suggesting that the peak therapeutic effect of MSC can be expected during the first week of the administration. Although allogeneic cells induced immunoglobulin production, their biological effects (cell survival, factor productions) are very similar to the syngeneic transplants and therefore they could deliver the same therapeutic effect as the syngeneic cells. Finally, freshly infarcted tissue (30 min) supported better the survival of MSC than late postischemic tissue (5 days) but only "off the shelf" allogeneic cell transplants fits with this treatment strategy.

The susceptibility of Colorado potato beetle [Leptinotarsa decemlineata (Say), Coleoptera: Chrysomelidae] to entomopathogenic nematodes (Steinernema carpocapsae, ’All’ strain, Nematoda: Heterorhabditae) was tested in the laboratory and the field in 1992 and 1993. Under laboratory conditions, applications of 5.0 × 105S. carpocapsae per square metre to larvae, pupae, and (or) adults resulted in 100% mortality in all experimental groups. Steinernema carpocapsae persisted through the larval–pupal and pupal–adult transitions. A single application of nematodes was sufficient to control the Colorado potato beetle. The following treatments were tested at field sites in New Brunswick and Prince Edward Island: (i) untreated check, (ii) application of nematodes, or (iii) application of insecticides. Straw mulch was either present or absent in each treatment. In 1992 in New Brunswick, nematodes and fenvalerate reduced Colorado potato beetle populations by 31% compared with the untreated check. However, in 1993, differences among treatments were not significant. The results from the field trials in Prince Edward Island were variable; the life expectancy of nematodes is likely shorter in the field than under laboratory conditions. Further investigation into the benefits of repeated applications of nematodes, higher rates, or improvements in application technology are required to achieve consistent control of the Colorado potato beetle.

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