Direct Quantification of Circulating MiRNAs in Different Stages of Nasopharyngeal Cancerous Serum Samples in Single Molecule Level with Total Internal Reflection Fluorescence Microscopy

MicroRNAs (miRNAs) are small noncoding RNAs that regulate human gene expression at the post-transcriptional level. Growing evidence indicates that the expression profile of miRNAs is highly correlated with the occurrence of human diseases including cancers. Playing important roles in complex gene regulation processes, the aberrant expression pattern of various miRNAs is implicated in different types and even stages of cancer. Besides localizing in cells, many of these miRNAs are found circulating around the body in a wide variety of fluids such as urine, serum and saliva. Surprisingly, these extracellular circulating miRNAs are highly stable and resistant to degradation, and therefore, are considered as promising biomarkers for early cancer diagnostic via noninvasive extraction from body fluids. Unfortunately, the abundance of these small RNAs is ultralow in the body fluids, making it challenging to quantify them in complex sample matrixes. Establishing a sensitive, specific yet simple assay for an accurate quantification of circulating miRNAs is therefore desirable. Our group previously reported a sensitive and specific detection assay of miRNAs in single molecule level with the aid of total internal reflection fluorescence microscopy. In this work, we advanced the assay to differentiate the expression of a nasopharyngeal carcinoma (NPC) up-regulator hsa-mir-205 (mir-205) in serum collected from patients of different stages of NPC. To overcome the background matrix interference in serum, a locked nucleic acid-modified molecular beacon (LNA/MB) was applied as the detection probe to hybridize, capture and detect target mir-205 in serum matrix with enhanced sensitivity and specificity. A detection limit of 500 fM was achieved. The as-developed method was capable of differentiating NPC stages by the level of mir-205 quantified in serum with only 10 μL of serum and the whole assay can be completed in 1 h. The experimental results agreed well with those previously reported whereas the quantity of miR-205 determined by our assay was found comparable to that of quantitative reverse transcription polymerase chain reaction (qRT-PCR), supporting that this assay can be served as a promising noninvasive detection tool for early NPC diagnosis, monitoring and staging

Additional file 1: of Silica nanoparticles induce neurodegeneration-like changes in behavior, neuropathology, and affect synapse through MAPK activation

(Methods. Effects of FITC-SiO2-NPs on behavior in mice (Figure S1.) Effects of FITC-SiO2-NPs on phosphorylations of p38 and CREB and its effectors in total lysates of frontal cortex and hippocampus (Figure S2.) Protein levels of synaptophysin and synapsin I in the primary culture of cortical neurons exposed to NP for 48h as analyzed by Western blot (Figure S3.) DOCX 1064 kb

Effective Theranostic Cyanine for Imaging of Amyloid Species in Vivo and Cognitive Improvements in Mouse Model

We report herein an investigation of carbazole-based cyanine, (<i>E</i>)-4-(2-(9-(2-(2-methoxyethoxy)­ethyl)-9<i>H</i>-carbazol-3-yl)-vinyl)-1-methyl-quinolin-1-iumiodide (SLM), as an effective theranostic agent for Alzheimer’s disease (AD). This cyanine exhibited desirable multifunctional and biological properties, including amyloid-β (Aβ)-oligomerization inhibition, blood–brain barrier permeability, low neurotoxicity, neuroprotective effect against Aβ-induced toxicities, high selectivity and strong binding interactions with Aβ peptide/species, good biostability, as well as strong fluorescence enhancement upon binding to Aβ species for diagnosis and therapy of AD. This cyanine has been successfully applied to perform near-infrared in vivo imaging of Aβ species in transgenic AD mouse model. The triple transgenic AD mice intraperitoneally treated with SLM showed significant recovery of cognitive deficits. Furthermore, those SLM-treated mice exhibited a substantial decrease in both of oligomeric Aβ contents and tau proteins in their brain, which was attributed to the induction of autophagic flux. These findings demonstrated for the first time that SLM is an effective theranostic agent with in vivo efficacy for diagnosis and treatment of AD in mouse models