A triazatruxene-based glycocluster as a fluorescent sensor for concanavalin A.

A new triazatruxene-based fluorescent glycocluster has been designed, synthesized, and fully characterized by NMR spectroscopy and mass spectrometry. Furthermore, its specific and selective binding properties with concanavalin A (Con A) have been investigated by fluorescence spectroscopy, circular dichroism (CD) spectroscopy, and turbidity assay. The obtained results showed that the multivalent mannose-modified triazatruxene exhibited specific binding with Con A, but no binding to peanut agglutinin (PNA) lectin or bovine serum albumin (BSA), corresponding to a two-orders-of-magnitude higher affinity than that of monovalent mannose ligands. Most interestingly, a fluorescence enhancement of the triazatruxene-based glycocluster was observed upon binding with Con A because of hydrophobic interactions involving sites close to the triazatruxene moiety. Furthermore, the inhibitory ability of the triazatruxene-based glycocluster against ORN178-induced haemagglutination has been investigated by haemagglutination inhibition assay. The results indicated selective binding with ORN178.

Synthesis of perylene bisimide-centered glycodendrimer and its interactions with concanavalin A.

A novel glycodendrimer based on 18 peripheral α-D-mannoses functionalized perylene bisimide derivative PBI-18-Man was synthesized and its selectively binding interactions for Con A were investigated by CD spectra and turbidity assay, which exhibited strong binding affinity for Con A with the binding constant of 1.3×10(8) M(-1) (7.2×10(6) M(-1) for monomeric mannose, valency corrected), 3 orders of magnitude higher affinity than the monovalent mannose ligand. Furthermore, the inhibitory activity for Con A was studied by ELLA experiment, showed 2 times inhibitor activity than the reference compound (α-MMP).

Multivalent glycoclusters constructed by chiral self-assembly of mannose functionalized perylene bisimide.

Water-soluble perylene bisimide derivative 7 modified with six mannoses was synthesized and its self-assembled properties were studied by UV-Vis and CD spectroscopy, which revealed an interesting self-assembly with a solvent-tuning chiral conformation in H(2)O-DMSO solution. As H(2)O was added to the DMSO solution until a 60% (or 70%) v/v proportion was achieved, the self-assembly of the mannose functionalized compound 7 exhibited a left-handed helical conformation. More interestingly, when the volume of H(2)O constituted beyond 85% of the solution, the conformation of the self-assembly turned out to be a right-handed helical conformation. Furthermore, the binding interactions between the self-assembly of compound 7 and Con A were investigated by turbidity assay, CD spectra, TEM and SEM images, and ELLA experiment, which indicated that the self-assembly of compound 7 as multivalent glycoclusters exhibited specific binding to Con A with an IC(50) value of 24 µM (144 µM, valency corrected), 10 times stronger than the reference compound (α-MMP).

Prolonged blood circulation outperforms active targeting for nanocarriers-mediated enhanced hepatocellular carcinoma therapy in vivo.

Successful hepatocellular carcinoma (HCC) therapy in vivo remains a significant challenge due to the down-regulated expression of the receptors on the surface of tumor cells for compromised active targeting efficiency and cellular uptake of nanoparticles (NPs)-based drug delivery systems (DDSs) and "accelerated blood clearance" and premature unpackaging of NPs in vivo induced by the poly(ethylene glycol)ylation (PEGylation). Inspired by the repeatedly highlighted prolonged blood circulation property of RBCm-camouflaged NPs, we hypothesis that the prolonged blood circulation property resulting from RBCm coating outperforms the active targeting mechanisms of various targeting ligands for enhanced HCC therapy in vivo. Clarification of this hypothesis is therefore of great significance and urgency to break the afore mentioned bottlenecks that hamper the efficient HCC treatment in vivo. For this purpose, we reported in this study the first identification of a determining factor of nanocarriers for enhanced HCC therapy in vivo by the use of the previously fabricated pectin-doxorubicin nanoparticles (PDC-NPs) as a typical example, i.e., the natural RBCm was used as a stealth coating of PDC-NPs for the fabrication of biomimetic DDSs, PDC@RBC-NPs via hypotonic dialysis and mechanical co-extrusion methods. Comprehensive in vitro and in vivo evaluation and comparison of the properties and performance of PDC@RBC-NPs and PDC-NPs were performed in terms of colloidal stability, biosafety, drug release profiles, macrophage escape, anti-HCC effect. The resulting PDC@RBC-NPs outperformed PDC-NPs for HCC therapy in vitro and in vivo. Notably, PDC@RBC-NPs-treated BALB/c nude mice showed a significantly smaller final average tumor volume of 613 mm3 after 16 days than the PDC-NPs-treated group with an average value of 957 mm3. Therefore, the PDC@RBC-NPs developed herein showed great potential for clinical transformations due to the facile preparation and superior therapeutic efficiency against HCC. Most importantly, prolonged blood circulation was identified as a determining factor of nanocarriers instead of active targeting for enhanced HCC therapy in vivo, which could be used to direct the future design and development of advanced DDSs with greater therapeutic efficiency for HCC.

Cannabinoid receptor agonist WIN55,212-2 and fatty acid amide hydrolase inhibitor URB597 may protect against cognitive impairment in rats of chronic cerebral hypoperfusion via PI3K/AKT signaling.

The present study further investigated the protective effects of cannabinoid receptor agonist WIN55,212-2 (WIN) and fatty acid amide hydrolase (FAAH) inhibitor URB597 (URB) on chronic cerebral hypoperfusion (CCH)-induced cognitive impairment in rats. Spatial learning and memory were assessed with the Morris water maze and by measuring Long-term potentiation. The expression of microtubule-associated protein-2 (MAP)-2, growth-associated protein-43 (GAP)-43, synaptophysin, cannabinoid receptor 1 (CB1), brain-derived neurotrophic factor (BDNF), FAAH, N-acylphosphatidylethanolamine phospholipase D(NAPE-PLD) and monoacyl glycerol lipase (MGL) as well as phosphoinositide 3-kinase (PI3K)/AKT signaling pathway molecules and downstream targets including AKT, phosphorylated (p-)AKT, cyclic AMP response element- binding protein (CREB), p-CREB, Bcl-2-associated death protein (BAD), p-BAD, glycogen synthase kinase (GSK)-3ß, p-GSK-3ß, forkhead box protein (FOXO) 3A and p-FOXO3A was determined by western blotting. WIN and URB treatment improved learning and memory performance, effects that were abolished by co-administration of the PI3K/AKT inhibitor LY294002. Moreover, WIN and URB reversed the decreases in MAP-2 and synaptophysin expression resulting from CCH, and stimulated BDNF and CB1 expression as well as CREB, FOXO3A, GSK-3ß, and BAD phosphorylation, confirming that WIN and URB mediate neuroprotection by preventing neuronal apoptosis and improving cognition via PI3K/AKT signaling. These findings suggest that WIN and URB are promising agents for therapeutic management of CCH.

[Spectrum analysis of crop and weeds at seedling].

The infestation information on field weeds is the basis of variable spraying herbicides. It was found that the method using the spectral characteristics of plant is superior in real-time respect. The Fourier transform infrared spectrum technique was applied to measure the reflectance of wheat and weeds in the range from 700 to 1100 nm. The discrimination analysis was done using the SPSS software. Firstly, the source spectrum data were compressed and normalized. Secondly, the characteristic wavelengths were selected by using stepwise method. Thirdly, the discrimination model was set up to use the selected wavelengths as the variables for detecting wheat and weeds. It was shown by the result of discrimination analysis that the correct classification rate of wheat and weeds detection with the selected wavelength points achieved 97%. In addition, the selected wavelength points were marked in the "red edge" of reflectance within some range, and the rate of correct classification increased with the increase in the numbers of the selected wavelength points. According to the selected wavelength points, the proper filters were chosen to perform the multi-spectral images captured and processed with the machine vision system.

miR-150, p53 protein and relevant miRNAs consist of a regulatory network in NSCLC tumorigenesis.

microRNAs (miRNAs) are a class of non-coding small RNAs that act as negative regulators of gene expression by binding to the 3'-untranslated region (3'-UTR) of target mRNAs. Tumor protein p53, a transcriptional factor, plays an important role in the progression of tumorigenesis. miR-150 was the only miRNA predicted to target 3'-UTR of p53 by Targetscan. In order to investigate the function of miR-150, p53 and relevant miRNAs in non-small cell lung cancer (NSCLC), we constructed two expression vectors of p53 (pcDNA3.1-p53 and pcDNA3.1-p53-3'-UTR) and two report vectors (pGL3-p53-3'-UTR and pGL3-p53-3'-mUTR). The activity of luciferase transfected with miR-150 mimics was lower by 30% when compared to that of the miRNA-negative control (miRNA-NC). Moreover, the p53 protein was downregulated by at least 50% when miR-150 mimics were cotransfected with pcDNA3.1-p53-3'-UTR when compared to miRNA-NC. We also determined the expression of miR-150 and p53 in NSCLC patient tissue samples. The expression of miR-150 in T2 stage tissue samples was higher than that in T1 stage tissue samples. The corresponding target gene p53 was correlated with miR-150 expression. In the present study, we further analyzed the cell cycle distribution. The cells transfected with pcDNA3.1-p53 were significantly arrested in the G1 phase when compared to the control cells. When miR-150 mimics were cotransfected with pcDNA3.1-p53-3'-UTR, the percentage of cells in the G1 phase was significantly lower by 4% when compared to miRNA-NC. To identify miRNAs that are regulated by the p53 protein, qRT-PCR was performed after pcDNA3.1-p53 transfection. miR-34a, miR-184, miR-181a and miR-148 were upregulated significantly. However, there was no distinct difference in the expression of miR-10a, miR-182 and miR-34c. Our results showed that miR-150 targets the 3'-UTR of p53, and p53 protein promotes the expression of miRNAs which affect cell cycle progression. These findings suggest that miR-150, p53 protein and relevant miRNAs are members of a regulatory network in NSCLC tumorigenesis.