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Barbara S. Shane Errol Zeiger Walter W. Piegorsch Ewan D. Booth Jay I. Goodman Richard C. Peffer 《Environmental and molecular mutagenesis》2012,53(1):1-9
Propiconazole (PPZ) is a conazole fungicide that is not mutagenic, clastogenic, or DNA damaging in standard in vitro and in vivo genetic toxicity tests for gene mutations, chromosome aberrations, DNA damage, and cell transformation. However, it was demonstrated to be a male mouse liver carcinogen when administered in food for 24 months only at a concentration of 2,500 ppm that exceeded the maximum tolerated dose based on increased mortality, decreased body weight gain, and the presence of liver necrosis. PPZ was subsequently tested for mutagenicity in the Big Blue® transgenic mouse assay at the 2,500 ppm dose, and the result was reported as positive by Ross et al. ([2009]: Mutagenesis 24:149‐152). Subsets of the mutants from the control and PPZ‐exposed groups were sequenced to determine the mutation spectra and a multivariate clustering analysis method purportedly substantiated the increase in mutant frequency with PPZ (Ross and Leavitt. [2010]: Mutagenesis 25:231‐234). However, as reported here, the results of the analysis of the mutation spectra using a conventional method indicated no treatment‐related differences in the spectra. In this article, we re‐examine the Big Blue® mouse findings with PPZ and conclude that the compound does not act as a mutagen in vivo. © Environ. Mol. Mutagen. 2012. Published 2011 Wiley Periodicals, Inc. 相似文献
283.
Aims: The purpose of this pilot study was to determine the feasibility and usability of daily retrospective assessments of alcohol use using handheld computers and to explore their comparability to Timeline Followback (TLFB) assessments.Methods: College student participants received a Handheld Assessment Tool (HAT) at enrolment, which surveyed alcohol consumption and contextual factors for the previous day. After 1 week of daily monitoring, participants completed a paper‐and‐pencil TLFB assessment and HAT usability scale.Results: Of the 1,800 matched data points on the HAT and TLFB, the overall level of agreement was very good (kappa = 0.80, p<0.001). The mean difference between the number of drinks per drinking days recorded using both methods was 0.19 (SD = 0.56). Participants completed HAT surveys on 87 out of 91 total possible survey days (95.6%). The HAT recorded 34 drinking days and the TLFB recorded 37 out the 91 possible days; the HAT was reported to be highly usable by all participants.Conclusion: Overall, the HAT was found to be usable and feasible and produced high adherence. Further research should validate this alcohol assessment approach and apply it to representative populations. 相似文献
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Jianguang Peng Haley McKissack Jonathan Yu Jun Kit He Tyler Montgomery Leonardo Moraes Bradley Alexander Ashish Shah 《Foot and Ankle Surgery》2021,27(2):162-167
IntroductionPercutaneous anterior-posterior (AP) screw is an option for posterior malleolus fracture fixation when the fracture fragment can be reduced indirectly by the mean of ligamentotaxis. However, anterior anatomic structures could be injured during screw placement.Materials and methodsEleven below-knee cadavers were employed for the placement of AP screws in an attempt of fixing assumed Haraguchi Type-I posterior malleolar fractures. Three entry points were selected as medial to the anterior tibial tendon (ATT), lateral to the ATT, and lateral to the extensor digitorum longus (EDL). Three AP screws were placed under guidance of fluoroscopy. After dissection, measurements were made (mm) from each screw to nearby structures. Distances were calculated and damage to structures was documented.ResultsMean, minimum, and maximum distances from the medial screw to the greater saphenous vein, TA, EHL, anterior tibial artery (ATA), and deep peroneal nerve (DPN), were 18.1 (12–25) mm, 2.0 (0–5) mm, 13.6 (9–20) mm, 16.6 (9–25) mm, and 20.1 (12–27) mm. From the middle screw to the ATA, DPN, TA, EHL, and EDL, were 1.2 (0–3) mm, 4.9 (3–9) mm, 3.8 (1–7) mm, 0.4 (0–2) mm, and 13.6 (10–18) mm. From the lateral screw to the superficial peroneal nerve (SPN), EDL, DPN, and ATA, were 10.8 (0–16) mm, 1.2 (0–4) mm, 15.9 (11–25) mm, 19 (15–27) mm. The SPN was found partially cut by the lateral screw on 1 specimen.ConclusionsLateral and middle percutaneous AP screw placement put certain anatomic structures at-risk of injury. Medial screw placement did not result in appreciable damage to adjacent structures. Entry point of AP screws should be selected with respect to posterior malleolar fracture and anatomic structures.Level of evidenceIV. 相似文献
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Neeraj Sood Victoria L. Shier Haley Nakata Richard Iorio Jay R. Lieberman 《The Journal of arthroplasty》2019,34(4):609-612.e1
Background
Comprehensive Care for Joint Replacement (CJR) is a Medicare initiative to test the impact of holding a hospital accountable for services provided during an episode of care for a lower extremity joint arthroplasty on costs and quality. This study examines whether hospital participation in CJR is associated with having programs focused on improving posthospitalization care or reducing costs using a survey of orthopedic surgeons.Methods
Seventy-three (of 104) orthopedic surgeon members of the Hip Society, a national professional organization of hip surgeons, completed the survey.Results
Surgeons practicing in CJR hospitals were more likely to report that their hospital had implemented programs focused on improving posthospitalization care or reducing costs. Surgeons in CJR hospitals were significantly more likely to report that the hospital had a narrow network of skilled nursing facilities to enhance care and limit length of stay in skilled nursing facilities (83% vs 47%, P < .01). Surgeons in CJR hospitals were also more likely to report the hospital provides incentives or some type of gainsharing. There were no statistically significant differences in implementation of having programs to reduce costs or improve care during hospitalization.Conclusion
Participation in CJR is associated with higher utilization of hospital practices aimed at improving postdischarge care and higher utilization of linking surgeon compensation to cost and quality. 相似文献290.