Multi-state trials of Bt sweet corn varieties for control of the corn earworm (Lepidoptera: Noctuidae).

Field tests in 2010-2011 were performed in New York, Minnesota, Maryland, Ohio, and Georgia to compare Bt sweet corn lines expressing Cry1A.105 + Cry2Ab2 and Cry1Ab with their non-Bt isolines, with and without the use of foliar insecticides. The primary insect pest in all locations during the trial years was Heliocoverpa zea (Boddie), which is becoming the most serious insect pest of sweet corn in the United States. At harvest, the ears were measured for marketability according to fresh market and processing standards. For fresh market and processing, least squares regression showed significant effects of protein expression, state, and insecticide frequency. There was a significant effect of year for fresh market but not for processing. The model also showed significant effects of H. zea per ear by protein expression. Sweet corn containing two genes (Cry1A.105 + Cry2Ab2) and a single gene (Cry1Ab) provided high marketability, and both Bt varieties significantly outperformed the traditional non-Bt isolines in nearly all cases regardless of insecticide application frequency. For pest suppression of H. zea, plants expressing Bt proteins consistently performed better than non-Bt isoline plants, even those sprayed at conventional insecticide frequencies. Where comparisons in the same state were made between Cry1A.105 + Cry2Ab2 and Cry1Ab plants for fresh market, the product expressing Cry1A.105 + Cry2Ab2 provided better protection and resulted in less variability in control. Overall, these results indicate Cry1A.105 + Cry2Ab2 and Cry1Ab plants are suitable for fresh market and processing corn production across a diversity of growing regions and years. Our results demonstrate that Bt sweet corn has the potential to significantly reduce the use of conventional insecticides against lepidopteran pests and, in turn, reduce occupational and environmental risks that arise from intensive insecticide use.

Neonicotinoid insecticides disrupt predation on the eggs of turf-infesting scarab beetles.

Turfgrass applications of imidacloprid were previously shown to suppress the abundance of certain soil arthropods. To ascertain whether those impacts harbor functional consequences, the effect of neonicotinoids on Japanese beetle (Popillia japonica Newman) predation was examined in three experiments that measured removal of eggs implanted into non-irrigated field plots. A first experiment confirmed that a single imidacloprid application reduced the abundance of nontarget fauna and the rate of egg removal. A second experiment compared the impacts of imidacloprid with those of three other neonicotinoids, while a third measured the impact of imidacloprid when applied in July, August or September. Egg removal declined 28.3-76.1% in imidacloprid-treated plots across all studies. Effects were detected as early as one week after treatment (WAT) and persisted as long as four WAT. The extent of suppression did not vary across month of application. Clothianidin, dinotefuran and thiamethoxam also suppressed egg removal, and the effects were similar among them and with imidacloprid. There was no discernible association between variation in rainfall and treatment effects, but this was not explicitly tested. Results support the hypotheses that a single neonicotinoid application can suppress predation on pest populations and that the effect does not vary with respect to active ingredient or season of application. Neonicotinoid application at the time of beetle oviposition puts intended effects (mortality of neonates) in conflict with unintended effects (disruption of egg predation). The conservation of predation on early life stages might buffer the reduced efficacy of late season applications that target more advanced instars. As application timing and post-application irrigation affect insecticide performance, they might also be manipulated to reduce nontarget effects.

A double-blind controlled pilot study of plasma exchange versus sham apheresis in chronic progressive multiple sclerosis.

Twenty patients with chronically progressive multiple sclerosis (MS) were randomised in a double-blind controlled study to assess the efficacy of plasma exchange therapy. All patients were immunosuppressed with prednisone and azathioprine and underwent either plasma exchange or sham apheresis. The 10 patients in each group were similar in age, sex, duration of disease and degree of disability. Clinical and laboratory responses were assessed immediately following the course of exchange or sham therapy, and 3 to 6 months later, by individuals blinded to the type of therapy administered. Although modest improvement was suggested on clinical examination in 7 of 10 patients exchanged and 3 of the 10 sham treated group, this was transient and was not accompanied by any change in disability status scores. No differences in abnormal laboratory investigations were demonstrable between the two patient groups following therapy. We conclude that plasma exchange therapy using this protocol is unlikely to be of clinical benefit as an adjunct in the management of chronically progressive M.S.

Hospital-based technology assessment programmes: two Canadian examples.

Interest in Health Technology Assessment (HTA) has grown considerably in recent years. Organizations established specifically to conduct HTA and disseminate HTA results have sprung up in many countries. These have been, to a large extent, financed by governments. However, the relevance of HTA clearly goes beyond governments, and there are many sectors in health care that are potential consumers of HTA information. In particular, those running healthcare facilities are constantly faced with decisions on new equipment to purchase and new clinical procedures to offer. HTA is important not just to the senior administrators of such facilities but those in other levels of hospital management as well. In this paper, a brief review of Canadian and US studies on hospitals' technology assessment and acquisition is presented. Two specific examples of Canadian healthcare facilities and how HTA has been addressed in these institutions are discussed. Finally, this paper contains a discussion of some of the practical issues involved in introducing a formalized programme of HTA in hospitals.

Clarifying concurrent care.

Pennsylvania Blue Shield's concurrent care policy for both the Medicare program and its private business is the source of much confusion and exasperation among physicians, especially with regard to medical-medical concurrent care. This article seeks to clarify the process for better understanding by physicians.

New act expands efforts against fraud and abuse.

President Clinton on August 21 signed into law the Health Insurance Portability and Accountability Act of 1996. Though much of the publicity surrounded passage of the bill centered on the provision of insurance portability, limits on preexisting condition exclusions, and the establishment of a medical savings account pilot project, the bill also includes a major initiative to expand federal efforts to combat fraud and abuse. This overview highlights the most significant elements of that initiative.

Understanding Medicare risk contracting.

Managed care plans currently serve Medicare beneficiaries through three types of contracts: risk, cost, and health care prepayment plans. This first in a series of articles on Medicare managed care answers common questions about risk contracts.

Medicare monitoring of payment reform.

Medicare payment reform became effective January 1, 1992. One aspect is monitoring by Medicare carriers of payment reform initiatives and physician compliance with these initiatives.