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Zinc phthalocyanine labelled polyethylene glycol was prepared to track and monitor the in vivo fate of polyethylene glycol. The chemical structures were characterized by nuclear magnetic resonance and infrared spectroscopy. Their light stability and fluorescence quantum yield were evaluated by UV-Visible and fluorescence spectroscopy methods. The interaction of zinc phthalocyanine labelled polyethylene glycol with bovine serum albumin was evaluated by fluorescence titration and isothermal titration calorimetry methods. Optical imaging in vivo, organ aggregation as well as distribution of fluorescence experiments for tracking polyethylene glycol were performed with zinc phthalocyanine labelled polyethylene glycol as fluorescent agent. Results show that zinc phthalocyanine labelled polyethylene glycol has good optical stability and high emission ability in the near infrared region. Imaging results demonstrate that zinc phthalocyanine labelled polyethylene glycol can track and monitor the in vivo process by near infrared fluorescence imaging, which implies its potential in biomaterials evaluation in vivo by a real-time noninvasive method.

Chitosan was prepared by alkaline N-deacetylation of β-chitin from squid pens, and N-carboxyethylated derivatives (N-CECS) with different degrees of substitution (DS) were synthesized. The carboxyethylation of the polysaccharide was identified by Fourier transform infrared, (1)H and (13)C nuclear magnetic resonance (NMR), and X-ray diffraction analyses. The DS of the derivatives was calculated by (1)H NMR and elemental analysis. All three N-CECS samples showed good water solubility at pH > 6.5. The antioxidant properties and bile acid binding capacity of the derivatives were studied in vitro. The highest bile acid binding capacity of all N-CECS reached 36.9 mg/g, which was 2.6-fold higher than that of chitosan. N-CECS showed a stronger scavenging effect on 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical ability, and EC50 values were below 2 mg/mL. The scavenging ability of N-CECS against superoxide radicals correlated well with the DS and concentration of N-CECS. These results indicated that N-carboxyethylation is a possible approach to prepare chitosan derivatives with desirable in vitro biochemical properties.

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A band-pass flat-response x-ray detector is designed to measure the absolute M-band x-ray flux. The detector comprises an x-ray diode and a compound filter that is carefully designed to achieve the desired response function in the range from 1.6 to 4.4 keV, i.e. the flatness of the spectral response is better than 5%. The designed response function is in excellent agreement with the calibrated one, indicating that the x-ray detector with various responses can be achieved with the state-of-art fabrication technique.

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BACKGROUND: Because of its high demand for use in pharmaceutical products, cosmetics, soil remediation technologies, etc., randomly methylated β-cyclodextrin (RM-β-CD) is one of the most important cyclodextrin (CD) derivatives. The aim of this present work is to use a green and commercially available approach to obtain RM-β-CD. Compared with other methylated CDs, RM-β-CD with an asymmetric molecular structure has higher water solubility. When the degree of substitution (DS) is about 1.8, the solubility tends to increase with increasing temperature and is suitable for pharmaceutical applications.

Long noncoding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) is abnormally expressed in numerous tumors and functions as an oncogene, but the role of NEAT1 in laryngocarcinoma is largely unknown. Our study validated that NEAT1 expression was markedly upregulated in laryngocarcinoma tissues and cells. Downregulation of NEAT1 dramatically suppressed cell proliferation and invasion through inhibiting miR-524-5p expression. Additionally, NEAT1 overexpression promoted cell growth and metastasis, while overexpression of miR-524-5p could reverse the effect. NEAT1 increased the expression of histone deacetylase 1 gene (HDAC1) via sponging miR-524-5p. Mechanistically, overexpression of HDAC1 recovered the cancer-inhibiting effects of miR-524-5p mimic or NEAT1 silence by deacetylation of tensin homolog deleted on chromosome ten (PTEN) and inhibiting AKT signal pathway. Moreover, in vivo experiments indicated that silence of NEAT1 signally suppressed tumor growth. Taken together, knockdown of NEAT1 suppressed laryngocarcinoma cell growth and metastasis by miR-524-5p/HDAC1/PTEN/AKT signal pathway, which provided a potential therapeutic target for laryngocarcinoma.