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The resistance to the Bacillus thuringiensis (Bt) toxin Cry2Ab in a greenhouse-originated Trichoplusia ni strain resistant to both Bt toxins Cry1Ac and Cry2Ab was characterized. Biological assays determined that the Cry2Ab resistance in the T. ni strain was a monogenic recessive trait independent of Cry1Ac resistance, and there existed no significant cross-resistance between Cry1Ac and Cry2Ab in T. ni. From the dual-toxin-resistant T. ni strain, a strain resistant to Cry2Ab only was isolated, and the Cry2Ab resistance trait was introgressed into a susceptible laboratory strain to facilitate comparative analysis of the Cry2Ab resistance with the susceptible T. ni strain. Results from biochemical analysis showed no significant difference between the Cry2Ab-resistant and -susceptible T. ni larvae in midgut proteases, including caseinolytic proteolytic activity and zymogram profile and serine protease activities, in midgut aminopeptidase and alkaline phosphatase activity, and in midgut esterases and hemolymph plasma melanization activity. For analysis of genetic linkage of Cry2Ab resistance with potential Cry toxin receptor genes, molecular markers for the midgut cadherin, alkaline phosphatase (ALP), and aminopeptidase N (APN) genes were identified between the original greenhouse-derived dual-toxin-resistant and the susceptible laboratory T. ni strains. Genetic linkage analysis showed that the Cry2Ab resistance in T. ni was not genetically associated with the midgut genes coding for the cadherin, ALP, and 6 APNs (APN1 to APN6) nor associated with the ABC transporter gene ABCC2. Therefore, the Cry2Ab resistance in T. ni is conferred by a novel but unknown genetic mechanism.T he Gram-positive soil bacterium Bacillus thuringiensis (Bt) has been widely used as a microbial insecticide in sprayable formulations, and Bt toxins are the primary insecticidal proteins expressed in genetically engineered crops to confer insect resistance (1; ISAAA's GM Approval Database, http://www.isaaa.org /gmapprovaldatabase/). Since the mid-1990s, insect-resistant Bt crops have been rapidly adopted with proven economic and environmental benefits (2, 3). However, development of insect resistance to Bt toxins threatens the long-term success of application of Bt toxins for insect pest control. The genetic potential of insect populations to evolve Bt resistance has been well shown in laboratory selections, and cases of insect resistance to Bt formulations and Bt crops have occurred in insect populations under selection pressure by Bt sprays and Bt crops in the field (4-8).Studies of insect resistance to Bt toxins have so far been mostly on Lepidoptera pests to the toxin Cry1Ab or Cry1Ac (9-19), the two major Bt Cry toxins which are highly toxic to Lepidoptera pests and known to share the same binding sites in target insects (4, 20). Cry1Ab and Cry1Ac are the primary insecticidal proteins expressed in the current commercial transgenic Bt maize and Bt cotton varieties to target Lepidoptera pests in the field (21). Resistance to Cry1Ac and Cry1Ab ...

Background-There is limited guidance on how to longitudinally administer simulation materials or to incorporate video recordings into assessment portfolios of simulated surgical skills.Materials and Methods-We launched a longitudinal weekly simulation curriculum for PGY1-PGY3 surgical residents based on the ACS/APDS Curriculum. Residents underwent monthly Objective Structured Assessment of Technical Skills (OSATS) while wearing head-mounted cameras. Videos of OSATS performance accrued into individual online video portfolios. Residents were surveyed about their attitudes toward video recording.Results-Twenty-seven general surgical residents participated, completing 161 OSATS encompassing 11 distinct skills and generating 258 videos of simulated skills performance. The overall survey response rate was 88%. Residents viewed the curriculum favorably overall, and 36.4% of residents accessed their videos. Of those who did not watch their videos, 78.6% cited not having enough time, while 28.6% did not think the videos would be useful. Over 95% of surveyed residents expressed interest in having a video library of attending-performed procedures, 59.1% were interested in having their own operations recorded, and 45.5% were interested in video-based coaching. Conclusion-Residents viewed longitudinal administration of the ACS/APDS Curriculum positively. While video recording in simulation is feasible, resident interest may be higher for intraoperative recordings than for simulated skills.

Papillary thyroid cancer is the most common thyroid malignancy, and although metastatic spread is typically confined to regional lymph nodes, there are rare documented cases of distant spread of disease. Here we present an unusual case of metastatic papillary thyroid cancer that has spread to the subcutaneous tissue and muscle of the back. We report a case of an 89-year-old female presenting with a painful mass on her back. A positron emission tomography (PET) scan demonstrated a hypermetabolic lesion corresponding to the palpable mass, with a subsequent core needle biopsy confirming the diagnosis of metastatic papillary thyroid carcinoma (PTC). The patient underwent radical excision of the malignant soft tissue mass, removing subcutaneous tissue, superficial fascia, and underlying muscle.