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Sharon Medcalf Laura Bilek Teresa Hartman Peter C. Iwen Patricia Leuschen Hannah Miller Anne O’Keefe Harlan Sayles Philip W. Smith 《Emerging infectious diseases》2015,21(8):1437-1439
To evaluate the need to revaccinate laboratory workers against smallpox, we assessed regular revaccination at the US Laboratory Response Network’s variola testing sites by examining barriers to revaccination and the potential for persistence of immunity. Our data do not provide evidence to suggest prolonging the recommended interval for revaccination. 相似文献
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Launch of clinical investigation represents a substantial escalation in commitment to a particular clinical translation trajectory; it also exposes human subjects to poorly understood interventions. Despite these high stakes, there is little to guide decision-makers on the scientific and ethical evaluation of early phase trials. In this article, we review policies and consensus statements on human protections, drug regulation, and research design surrounding trial launch, and conclude that decision-making is largely left to the discretion of research teams and sponsors. We then review what is currently understood about how research teams exercise this discretion, and close by laying out a research agenda for characterizing the way investigators, sponsors, and reviewers approach decision-making in early phase research. 相似文献
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Anam Tariq Hannah Kim Hashim Abbas Gregory M. Lucas Mohamed G. Atta 《Expert opinion on pharmacotherapy》2021,22(1):69-82
ABSTRACT
Introduction
Since the developmentof combined antiretroviral therapy (cART), HIV-associated mortality and the incidence of HIV-associated end-stage kidney disease (ESKD) has decreased. However, in the United States, an increase in non-HIV-associated kidney diseases within the HIV-positive population is expected. 相似文献68.
Hannah A. Bullock Cynthia S. Goldsmith Sherif R. Zaki Roosecelis B. Martines Sara E. Miller 《Emerging infectious diseases》2021,27(4):1023
Efforts to combat the coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have placed a renewed focus on the use of transmission electron microscopy for identifying coronavirus in tissues. In attempts to attribute pathology of COVID-19 patients directly to tissue damage caused by SARS-CoV-2, investigators have inaccurately reported subcellular structures, including coated vesicles, multivesicular bodies, and vesiculating rough endoplasmic reticulum, as coronavirus particles. We describe morphologic features of coronavirus that distinguish it from subcellular structures, including particle size range (60–140 nm), intracellular particle location within membrane-bound vacuoles, and a nucleocapsid appearing in cross section as dense dots (6–12 nm) within the particles. In addition, although the characteristic spikes of coronaviruses may be visible on the virus surface, especially on extracellular particles, they are less evident in thin sections than in negative stain preparations. 相似文献
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Daniel H. Nussey Hannah Froy Jean-François Lemaitre Jean-Michel Gaillard Steve N. Austad 《Ageing research reviews》2013,12(1):214-225
That senescence is rarely, if ever, observed in natural populations is an oft-quoted fallacy within bio-gerontology. We identify the roots of this fallacy in the otherwise seminal works of Medawar and Comfort, and explain that under antagonistic pleiotropy or disposable soma explanations for the evolution of senescence there is no reason why senescence cannot evolve to be manifest within the life expectancies of wild organisms. The recent emergence of long-term field studies presents irrefutable evidence that senescence is commonly detected in nature. We found such evidence in 175 different animal species from 340 separate studies. Although the bulk of this evidence comes from birds and mammals, we also found evidence for senescence in other vertebrates and insects. We describe how high-quality longitudinal field data allow us to test evolutionary explanations for differences in senescence between the sexes and among traits and individuals. Recent studies indicate that genes, prior environment and investment in growth and reproduction influence aging rates in the wild. We argue that – with the fallacy that wild animals do not senesce finally dead and buried – collaborations between bio-gerontologists and field biologists can begin to test the ecological generality of purportedly ‘public’ mechanisms regulating aging in laboratory models. 相似文献