Sensitive and reversible perylene derivative-based fluorescent probe for acetylcholinesterase activity monitoring and its inhibitor.

A reversible fluorescence probe for acetylcholinesterase activity detection was developed based on water soluble perylene derivative, N,N'-di(2-aspartic acid)-perylene-3,4,9,10-tetracarboxylic diimide (PASP). Based on the photo-induced electron transfer (PET), PASP fluorescence in aqueous is quenched after combining with copper ions (Cu2+). Acetylcholinesterase (AChE) is well known to catalyze the hydrolysis of acetylcholine (ATCh) to produce thiocholine, whose affinity is strong enough to capture Cu2+ by thiol (-SH) group from the complex PASP-Cu, resulting in the fluorescence signal of PASP recovers up to 90%. This optical switch is highly sensitive depended on the coordination and dissociation between PASP and Cu2+. We proposed its application for AChE activity detection, as well as its inhibitor screening. According to the change of fluorescence intensity, quantifying the detection limit of AChE was 1.78 mU·mL-1. Classical inhibitors, tacrine and organophosphate pesticide diazinon, were further evaluated for drug screening. The IC50 value of tacrine was calculated to be 0.43 µM, and the detection limit of diazinon was 0.22 µM. Both of these performances were much better than previous results, revealing our probe is sensitive and reversible for screening applications.

Correlation between women's sub-health and reproductive diseases with pregnancies and labors.

OBJECTIVE: To investigate whether female sub-health conditions and reproductive diseases are associated with pregnancies and labors. METHODS: A cross-sectional survey was performed by using a structured questionnaire. A total of 1343 women aged 35 years or younger in six urban areas of Chengdu were included in the study. According to the Screening Criteria of sub-health conditions, these women were categorized into three groups: postpartum healthy group, sub-healthy group, and reproductive disease group. Data were double-entered using EpiData and then analyzed by SPSS. RESULTS: Pregnancy and labor were correlated with postpartum sub-health conditions. The number of pregnancies was negatively correlated with women's postnatal health but was positively correlated with the incidence of postpartum reproductive diseases. CONCLUSION: The number of pregnancies and labors is probably an important factor leading to sub-health conditions and the occurrence of reproductive diseases in women. Avoiding or reducing unwanted pregnancies and labors, enhancing the awareness of health among childbearing-age women are effective measures for preventing sub-health conditions.

New horizons for diagnostics and therapeutic applications of graphene and graphene oxide.

Graphene, a one-atom-thick two-dimensional (2D) layer of sp(2) -bonded carbon, has received worldwide attention owing to its extraordinary physical and chemical properties. Recently, great efforts have been devoted to explore potential applications of graphene and its oxide in life science, especially in disease-related diagnostics, near-Infrared (NIR) phototherapy and imaging. Here we will introduce recent advances and new horizons in this area, and focus on the rising progress on NIR photothermal therapy for cancer and Alzheimer's disease (AD), human telomerase detection, stem cell proliferation and differentiation on graphene substrate, diagnosis of cancer cell and related biomarkers, drug/nucleotide/peptide delivery and cell imaging, which have not been comprehensively reviewed. We hope to provide an outlook to the applications of graphene and its oxide, especially on the new horizons in this field, and inspire broader interests across various disciplines.