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Luminol is a presumptive test reagent used for the location of latent bloodstains. Various formulations are used by different forensic practitioners and commercial products are also widely available. There is little concurrence between authors with regards to the sensitivity limits of luminol which can vary significantly depending upon the substrate. We evaluated the sensitivity and stability of five different luminol formulations on a range of blood dilutions. All formulations showed an overall decrease in performance over 24 h though the effect was more gradual on a non-porous surface compared to porous. We found that BlueStar® Magnum showed the greatest sensitivity compared to other formulations and detected 50 μl of 1/100,000 blood dilutions on both porous and non-porous surfaces. Two formulations of luminol were selected based on the result of the sensitivity and stability study and were assessed for their impact on the DNA profiling process. There was a statistically significant improvement in DNA profile peak area from luminol-treated samples when compared to control samples of neat blood stains. However, at the weaker blood dilution of 1/1,000, the difference between control and luminol-treated samples was dependent on the substrate type with porous (fabric) samples showing a significant difference and non-porous (tile) swabbed samples requiring further work to conclusively ascertain the effect. 相似文献
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Fang-Ping Chen Mei-Hua Chien Huang-Yang Chen Ting-Shuo Huang Yuet-Tong Ng 《Taiwanese journal of obstetrics & gynecology》2013,52(3):365-373
ObjectivesTo examine the effects of 17β-estradiol (E2) and progestogens, used in hormone therapy, on estrogen receptors (ER), progesterone receptors (PR), and human breast tumor cell growth.Materials and methodsMCF-7 cells were incubated in pure E2 (1 nM and 10 nM) as well as in E2 in conjunction with 10 nM progestogens, including progesterone (P4), medroxyprogesterone acetate (MPA), norethisterone acetate (NET), and cyproterone acetate (CPA). Cell proliferation, apoptosis, expression of caspase-3, and both ER and PR isoforms were evaluated.ResultsCaspase-3 was significantly diminished in cultures with only E2, whereas ERα significantly increased. A significant increase of caspase-3 in addition to the entire abolishment of E2-induced augmentation of ERα was observed in 1 nM E2 plus MPA and 10 nM E2 plus NET, whereas PR isoform B (PRB) was significantly increased. The ratios of apoptosis: proliferation significantly increased in 1 nM E2 plus progestogens (except P4) and 10 nM E2 plus NET. The changes of the PRA/PRB ratio were inversely related to the changes of the apoptosis to proliferation ratio. Significant increase of ERβ and PRB was noted in the E2 plus MPA or NET, in addition to a significant increase of ERα and decrease of PRA in the E2 plus CPA, as well as an increase of ERα and decrease of PRA and PRB in the E2 plus P4.ConclusionsThe combination of E2 and various progestogens resulted in diverging effects on ERs and PRs expressions, which induced different effects on MCF-7 cell growth. Compared with P4, aberrant hormone and biological activity of synthetic progestin, by way of altered receptor expression, may be an important factor in affecting breast cell growth. 相似文献
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Joel Martin Geiderman Sanjeev Malik James J. McCarthy Andy Jagoda 《The American journal of emergency medicine》2018,36(10):1881-1885
People identified as Very Important Persons (VIPs) often present or are referred to the Emergency Department (ED). Celebrities are a small subset of this group, but many others are included. Triage of these patients, including occasional prioritization, creates practical and ethical challenges. Treatment also provides challenges with the risks of over testing, overtreatment, over consultation, and over or under admission to the hospital. This article presents a practical and ethical framework for addressing the care of VIPs in the ED. 相似文献
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Corentin M. Barbu Alison M. Buttenheim Maria-Luz Hancco Pumahuanca Javier E. Quintanilla Calderón Renzo Salazar Malwina Carrión Andy Catacora Rospigliossi Fernando S. Malaga Chavez Karina Oppe Alvarez Juan Cornejo del Carpio César Náquira Michael Z. Levy 《Emerging infectious diseases》2014,20(12):2055-2063
Chagas disease vector control campaigns are being conducted in Latin America, but little is known about medium-term or long-term effectiveness of these efforts, especially in urban areas. After analyzing entomologic data for 56,491 households during the treatment phase of a Triatoma infestans bug control campaign in Arequipa, Peru, during 2003–2011, we estimated that 97.1% of residual infestations are attributable to untreated households. Multivariate models for the surveillance phase of the campaign obtained during 2009–2012 confirm that nonparticipation in the initial treatment phase is a major risk factor (odds ratio [OR] 21.5, 95% CI 3.35–138). Infestation during surveillance also increased over time (OR 1.55, 95% CI 1.15–2.09 per year). In addition, we observed a negative interaction between nonparticipation and time (OR 0.73, 95% CI 0.53–0.99), suggesting that recolonization by vectors progressively dilutes risk associated with nonparticipation. Although the treatment phase was effective, recolonization in untreated households threatens the long-term success of vector control. 相似文献