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To estimate seroprevalence of severe acute respiratory syndrome 2 (SARS-CoV-2) among healthcare, first response, and public safety personnel, antibody testing was conducted in emergency medical service agencies and 27 hospitals in the Detroit, Michigan, USA, metropolitan area during May–June 2020. Of 16,403 participants, 6.9% had SARS-CoV-2 antibodies. In adjusted analyses, seropositivity was associated with exposure to SARS-CoV-2–positive household members (adjusted odds ratio [aOR] 6.18, 95% CI 4.81–7.93) and working within 15 km of Detroit (aOR 5.60, 95% CI 3.98–7.89). Nurse assistants (aOR 1.88, 95% CI 1.24–2.83) and nurses (aOR 1.52, 95% CI 1.18–1.95) had higher likelihood of seropositivity than physicians. Working in a hospital emergency department increased the likelihood of seropositivity (aOR 1.16, 95% CI 1.002–1.35). Consistently using N95 respirators (aOR 0.83, 95% CI 0.72–0.95) and surgical facemasks (aOR 0.86, 95% CI 0.75–0.98) decreased the likelihood of seropositivity.  相似文献   
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The paper presents the synthesis of new artemisinin triazole derivatives via click chemistry and their in vitro cytotoxic evaluation against four cancer cell lines including MCF-7, LU-1, HL-60 and P388. The bioassay result showed that most of the target compounds were active against four cell lines, in which compounds 11g displayed the most potent inhibitory activity against HL-60 cell line with IC50 value of 2.5 μM.  相似文献   
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Healthcare personnel are recognized to be at higher risk for infection with severe acute respiratory syndrome coronavirus 2. We conducted a serologic survey in 15 hospitals and 56 nursing homes across Rhode Island, USA, during July 17–August 28, 2020. Overall seropositivity among 9,863 healthcare personnel was 4.6% (95% CI 4.2%–5.0%) but varied 4-fold between hospital personnel (3.1%, 95% CI 2.7%–3.5%) and nursing home personnel (13.1%, 95% CI 11.5%–14.9%). Within nursing homes, prevalence was highest among personnel working in coronavirus disease units (24.1%; 95% CI 20.6%–27.8%). Adjusted analysis showed that in hospitals, nurses and receptionists/medical assistants had a higher likelihood of seropositivity than physicians. In nursing homes, nursing assistants and social workers/case managers had higher likelihoods of seropositivity than occupational/physical/speech therapists. Nursing home personnel in all occupations had elevated seropositivity compared with hospital counterparts. Additional mitigation strategies are needed to protect nursing home personnel from infection, regardless of occupation.  相似文献   
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Frontotemporal lobar degeneration with motor neuron disease (FTLD-MND) is characterized by neuronal cytoplasmic inclusions containing TDP-43. Apolipoprotein E4 (apoE4), derived from the apoE ?4 allele, enhances brain atrophy in FTLD through unknown mechanisms. Here, we studied two siblings with C9ORF72-linked familial FTLD-MND, an apoE ?4 homozygote and an apoE ?3 homozygote. The apoE ?4 homozygote had more cognitive-behavioral symptoms, fronto-insulo-temporal atrophy, and apoE fragments and aggregates in the anterior cingulate cortex. ApoE formed complexes with TDP-43 that were more abundant in the apoE ?4 homozygote. Although differences seen in a sibling pair could arise due to chance, these findings raise the possibility that apoE4 exacerbates brain pathology in FTLD through formation of neurotoxic apoE fragments and interactions with TDP-43.  相似文献   
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