3D C-Co-N-anchored MWCNTs derived from metal-organic frameworks as high-performance electrochemical sensing platforms for the sensitive detection of adrenaline.

Metal-organic frameworks (MOFs) are composed of metal ions and organic ligands with high specific surface areas, controllable porous structures and abundant metal active sites, showing their extraordinary potential in electrochemical sensors. Here, a 3D conductive network structure (C-Co-N@MWCNTs) is designed by anchoring zeolite imidazole frameworks (ZIF-67) onto multi-walled carbon nanotubes (MWCNTs) and carbonizing them. The C-Co-N@MWCNTs exhibit excellent electron conductivity, a porous structure and considerable electrochemical active sites, which can effectively demonstrate high sensitivity and selectivity in the detection of adrenaline (Ad). The Ad sensor exhibited a low detection limit of 6.7 nmol L-1 (S/N = 3) and a wide linear range of 0.02 µmol L-1-1.0 mmol L-1. The developed sensor also displayed high selectivity, good reproducibility and repeatability. The C-Co-N@MWCNTs electrode was further employed in the detection of Ad in a real sample of human serum, suggesting that it is a promising candidate for electrochemical sensing of Ad.

Emerging role of competing endogenous RNA and associated noncoding RNAs in thyroid cancer.

Cancer of the thyroid is the most common endocrine malignancy. While treatment options are limited for individuals with medullary or anaplastic thyroid cancer, understanding the underlying mechanisms is vital to developing a successful thyroid cancer treatment strategy due to the tumor's multistep carcinogenesis. Non-coding RNAs (ncRNAs) have been associated with thyroid cancer progression in several recent studies; however, the role of regulatory interactions among different types of ncRNAs in thyroid cancer remains unclear. Recently, competing endogenous RNA (ceRNA) has been discovered as a mechanism demonstrating regulatory interactions among non-coding RNAs, including pseudogenes, long non-coding RNAs (lnRNAs), circular RNAs (circRNAs), and microRNAs (miRNAs). It has been concluded from the literature that numerous ceRNA networks are deregulated during the development, invasion, and metastasis of thyroid cancer, as well as in epithelial-mesenchymal transition (EMT) and drug resistance. Further understanding of these deregulations is important to develop diagnostic procedures for early detection of thyroid cancer and promising therapeutic options for effective treatment. The purpose of this review is to highlight the emerging roles of some newly found ceRNA members in thyroid cancer and outline the current body of knowledge regarding ceRNA, lncRNA, pseudogenes, and miRNAs.

Epigallocatechin-3-gallate promotes angiogenesis via up-regulation of Nfr2 signaling pathway in a mouse model of ischemic stroke.

Epigallocatechin-3-gallate (EGCG) is the major effective component of green tea and has been known as a potential anticancer drug because of its antioxidant and anti-angiogenic properties. EGCG has also been reported to have preventive effects against ischemic stroke via nuclear factor erythroid 2-related factor 2 (Nfr2) signaling pathway, but how EGCG affect angiogenesis after stroke remains unclear. In this study, we investigated whether EGCG treatment in the acute phase of ischemic stroke can promote angiogenesis in a mouse model of transient middle cerebral artery occlusion (MCAO). We assessed neurological function with modified neurologic severity score (mNSS) test, infarct volume by Nessl staining, angiogenesis and oxidative stress by immunofluorescence analysis, intravital lectin perfusion analysis, western blot analysis and enzyme-linked immunosorbent assay (ELISA). In order to explore the role of Nrf2 in the angiogenesis of MCAO+EGCG-treated mice, we used MAPK/ERK inhibitor PD98059 to block the activation of Nrf2. We found MCAO+EGCG-treated mice had better neurologic outcome, less infarct volume, more number of Ki67/CD31-positive vessels, higher vascular density, unregulated VEGF-VEGFR2 signaling pathway, increased Nrf2 expression and decreased oxidative stress than did MCAO+vehicle-treated mice. Blocking Nrf2 with PD98059 significantly reduced the expression of Nrf2, increased oxidative stress and abolished the angiogenic and neuroprotective effects of EGCG on MCAO mice. We conclude that EGCG treatment in the early stage of ischemic stroke can promote angiogenesis in MCAO mice, possibly via upregulation of Nrf2 signaling pathway.

[Fluorescence Spectroscopic Studies on Binding of 20 (S)-Protopanaxatriol with Bovine Serum Albumin].

The interaction between 20(S)-protopanaxatriol (PPT) and bovine serum albumin ( BSA) was studied with fluorescence quenching technique and ultra-violet absorption spectroscopy. The results indicated that PPT led to the intrinsic fluorescence quenching of BSA through a static quenching process .The binding constants of PPT with BSA obtained with fluorescence quenching method were calculated as 0.926 3×10(3) (298 K), 0.618 2×10(3) (308 K), 0.414 4×10(3) L·mol(-1)(318 K), respectively; while the number binding sites n were close to unity. The results showed that the driving force of the interaction between PPT and BSA was hydrogen bond and Van der Waals force. The result of synchronous fluorescence spectra showed that binding of PPT with BSA could induce conformational changes in BSA, that the part of tryptophan became more closely. According to Föster fluorescence resonance energy transfer theory, the binding distance r and energy-transfer efficiency E were respectively 26.2 nm and 0.32.