Background: Exosomes are nano-sized extracellular vesicles secreted by most cell types and abundantly present in body fluids, including blood, saliva, urine, cerebrospinal fluid, and breast milk. Exosomes can spread toxic amyloid-beta (Aβ) and hyperphosphorylated tau between cells, contributing to neuronal loss in Alzheimer's disease (AD). Objective: To explore changes in the morphology, number, and pathological protein levels of urinary exosomes in AD patients compared with age-matched healthy subjects. Methods: In this study, enzyme-linked immunosorbent assay was used to detect the levels of Aβ1-42 and P-S396-tau (normalized by CD63) in urinary exosomes of AD patients and matched healthy subjects. We used transmission electron microscopy and nanoparticle tracking analysis to observe the exosomes. Results: We found that the levels of Aβ1-42 and P-S396-tau in the urinary exosomes of AD patients were higher than those of matched healthy controls. Exosomes taken from AD patients were more numerous. Conclusion: The differences in levels of Aβ1-42 and P-S396-tau and the quantity of urinary exosomes between AD patients and healthy controls may provide a basis for early diagnosis of AD.

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Eight alkaloids were isolated from the bulb of FritillarIa wabuensis S. V. Tang et S. C. Yueh (Liliaceae), which is efficacious against cough. Five of them are known and identified as imperialine (1), peimisine (2), ebeinone (3), isoverticine (4), and imperialine fl-N-oxide (5), respectively. Alkaloid 5 is however, controversial. All the signals for both 1H-and 13C-NMR spectra of 5 were assigned unambigously by 2D NMR experiments, and 13C-NMR assignments previously described in the literature were revised. An X-ray structure of alkaloid 5 is presented.

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