Retinal vascular biomarkers for early detection and monitoring of Alzheimer's disease

The earliest detectable change in Alzheimer''s disease (AD) is the buildup of amyloid plaque in the brain. Early detection of AD, prior to irreversible neurological damage, is important for the efficacy of current interventions as well as for the development of new treatments. Although PiB-PET imaging and CSF amyloid are the gold standards for early AD diagnosis, there are practical limitations for population screening. AD-related pathology occurs primarily in the brain, but some of the hallmarks of the disease have also been shown to occur in other tissues, including the retina, which is more accessible for imaging. Retinal vascular changes and degeneration have previously been reported in AD using optical coherence tomography and laser Doppler techniques. This report presents results from analysis of retinal photographs from AD and healthy control participants from the Australian Imaging, Biomarkers and Lifestyle (AIBL) Flagship Study of Ageing. This is the first study to investigate retinal blood vessel changes with respect to amyloid plaque burden in the brain. We demonstrate relationships between retinal vascular parameters, neocortical brain amyloid plaque burden and AD. A number of RVPs were found to be different in AD. Two of these RVPs, venular branching asymmetry factor and arteriolar length-to-diameter ratio, were also higher in healthy individuals with high plaque burden (P=0.01 and P=0.02 respectively, after false discovery rate adjustment). Retinal photographic analysis shows potential as an adjunct for early detection of AD or monitoring of AD-progression or response to treatments.     

Reliability of the Brownish-flanked Bush Warbler’s soft song in male-male conflict

Background: Soft song is a low-amplitude song produced by many birds. Recent studies have confirmed that soft song is an aggressive signal. For example, the Brownish-flanked Bush Warblers Cettia fortipes use soft song in male-male conflicts, particularly prior to attacks. Although stable signaling systems require that signals be honest on average,models predict that cheating is an acceptable strategy for some individuals or in some contexts.Methods: This study aimed to test the reliability of soft song as an aggressive signal in the brownish-flanked bush warbler. We used mounted specimens accompanied by broadcast songs or soft songs to simulate a male attempting to invade an existing territory.Results: We found the mounted specimen that coupled playback of soft songs suffered more and quicker attacks from the territory owner and that the relationship between soft song and subsequent attack in the territory owner was far from perfect. We observed territory owners that both over-signaled(i.e., produced soft song but did not attack) and under-signaled(i.e., attacked without producing soft song). Under-signaling territory owners were relatively more commonly than were over-signaling territory owners, particularly in simulated intrusion that coupled playback of soft song with a mount specimen.Conclusions: We discuss the cost of producing soft song and the potential benefit of the unreliable use of soft song and propose a new hypothesis for under-signaling with soft song; i.e., under-signaling territory owners might benefit from taking the initiative in fights.     

霍奇金淋巴瘤治疗新进展：第55届美国血液学会年会报道

2013年第55届美国血液学会（ASH）年会针对霍奇金淋巴瘤（HL）进行了专题报道,包含早期放化疗治疗选择、靶向治疗进展及结节性淋巴细胞为主型的HL治疗现状等内容.文章强调HL的治疗需结合病程特点及评效结果制定个体化治疗计划,以兼顾近期有效率及远期生存率.靶向治疗的有效性以及结节性淋巴细胞为主型HL治疗策略尚需进一步临床试验数据支持.     

Training and certifying gastroenterologists as physician nutrition specialists

Because nutrition is an integral aspect of the science and practice of gastroenterology, all gastroenterology fellows should receive training in core aspects of nutrition (level 1 training). Some gastroenterologists also wish to train more extensively in nutrition (level 2) and become physician nutrition specialists. The Intersociety Professional Nutrition Education Consortium, composed of representatives from eight national societies with significant nutrition interests, including the American Gastroenterological Association, and three credentialing bodies, has developed a paradigm and training requirements for physician-nutrition specialists that recognizes their varied backgrounds and areas of interest. Opportunities exist for gastroenterology fellows to obtain physician nutrition specialist training within their gastroenterology fellowships and to be eligible to take the Certification Examination for Physician Nutrition Specialists offered by the new American Board of Physician Nutrition Specialists.* This article reviews the development of consensus on subspecialty training for physicians in nutrition; it also encourages directors of gastroenterology fellowships to develop training opportunities and gastroenterology fellows to consider identifying nutrition as an area of emphasis for their careers.     

Transmissible spongiform encephalopathies

Nosologically, transmissible spongiform encephalopathies (TSE or prion diseases) should be grouped with other neurodegenerative disorders such as Alzheimer's and Parkinson's diseases, which are all caused by toxic gain of function of an aberrant form of a constitutively expressed protein. Failure to clear these proteins from the brain induces neuronal dysfunction. Transmissibility is the property that separates TSE from other neurodegenerative diseases, and this property seems to reside within the structure of the abnormal protein. The human phenotypic range of these encephalopathies includes Creutzfeldt-Jakob disease and its variant form, kuru, Gerstmann-Str?ussler-Scheinker syndrome, and fatal familial insomnia. Notwithstanding the generally low incidence of TSE and their limited infectiousness, major epidemics such as bovine spongiform encephalopathy and kuru arise in situations where intraspecies recycling of the abnormal protein is sustained. Moreover, evidence of chronic subclinical infection in animals offers insights into pathogenesis and prompts re-evaluation of the notion of species barriers and present infection control measures. Since case-to-case transmission is the only known mechanism underlying epidemics of TSE, potential reservoirs of infectivity in the tails of epidemics need continued vigilance.