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Ultrathin KMnF 3 nanowires with several nanometers in diameter have been synthesized successfully by a high temperature organic solution method for the first time. The morphologies and size of the as-prepared products were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectra (XPS), respectively. Ultrathin KMnF 3 nanowires and nanoparticles can be selectively synthesized by adjusting the amount of oleylamine. Moreover, the magnetic properties have been investigated using a vibrating sample magnetometer (VSM). Magnetic hysteresis loops revealed that the as-prepared KMnF 3 nanowires exhibit stronger paramagnetic performance than that of as-prepared nanoparticles.

It is a significant challenge to develop nanoscale magnetic resonance imaging (MRI) contrast agents with high performance of relaxation. In this work, Gd3+-doped CaF2-based core–shell nanoparticles (CaF2:Yb,Er@CaF2:Gd) of sub-10 nm size were controllably synthesized by a facile sequential growth method. The as-prepared hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles modified using PEG-PAA di-block copolymer benefited from the presence of Gd only in the outer CaF2 layer of the nanoparticles, which exhibited r1 as high as 21.86 mM−1 s−1 under 3.0 T, seven times as high as that of commercially used gadopentetate dimeglumine (Gd-DTPA). Low cytotoxicity, no hemolysis phenomenon and no potential gadolinium ion leakage phenomenon of the hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles have been observed and confirmed. Clear vascular details can be observed in magnetic resonance angiography and obvious MR signal of 4T1 tumor area could be significantly improved by intravenous injection of the hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles at a low dosage in mice. A series of in vivo biological safety evaluations confirmed the good biocompatibility of the hydrophilic CaF2:Yb,Er@CaF2:Gd nanoparticles, which might be employed in clinical blood pool imaging and tumor diagnosis as a safe and efficient MRI probe.

Two 1-D homometallic coordination polymers 1 and 2 have been prepared by one-step hydrothermal reactions of carboxylate-functionalized salen ligands with Co(II) and Mn(II), respectively. Single-crystal X-ray diffraction analyses reveal that both the 1-D chains give 3-D supramolecular structures through intermolecular hydrogen bonds and ππ packing interactions. Magnetic investigation of 2 indicates the presence of antiferromagnetic interactions in 1-D chains.

Two new homometallic coordination polymers 1 and 2 have been prepared by the directly one-step hydrothermal reactions of a carboxylate-functionalized salen ligand with Zn(II) and Co(II) ions, respectively. 1 exhibits a 3D open framework built by [Zn4(μ4-O)(carboxylate)8] units and double Zn-salen ligands, while 2 shows a 1D chain structure constructed by cobalt ions and the ligand derived from the hydrolysis to one C N bond of salen ligand. The preliminary fluorescence measurements of 1–2 show the influence of structure on the property.

Heparin is an effective competitive antagonist of inositol 1,4,5-trisphosphate receptors (IP(3)Rs). It binds to IP(3)Rs and affects calcium homeostasis. Ultra-low-molecular-weight heparin (ULMWH) is heparin's derivative, the present study was designed to test the effects of ULMWH on intracellular calcium concentration ([Ca(2+)]i) in primary cultured neurons. [Ca(2+)]i was measured by Multilabel Counter Victor-1420 using Fura-2/AM as the calcium fluorescent probe. The results indicated that ULMWH decreased the resting [Ca(2+)]i with or without extracellular Ca(2+). They had no effects on high K(+)-induced elevation of intracellular Ca(2+) level indicating that ULMWH had no effect on external Ca(2+) influx mediated by voltage-dependent calcium channels. However, they partially reduced the increase in [Ca(2+)]i induced by glutamate. Furthermore, ULMWH significantly inhibited the inositol 1,4,5-trisphosphate (IP(3))-induced increase in [Ca(2+)]i both in cellular and subcellular level. These results suggest that ULMWH may reduce [Ca(2+)]i in neurons through suppressing Ca(2+) release from IP(3)-sensitive stores.

The electrochemical deposition of thiophene and CdSe on TiO2/ITO by cyclic voltammetry(CV) technique was carried out to study the influence of conditions on the preparation and photophysical performance of poly(thiophene) (PTh)/CdSe double layers electrode. The chemical structure of the obtained polymer was characterized by FT-IR, Raman, X-ray diffraction, UV-vis spectroscopy. The morphology was observed by electronic scanning microscope (SEM) which showed nano-grain shape. Finally the photovoltaic performance of the solar cell which was composed of PTh/CdSe/TiO2 composite film used as working electrode, Pt used as counter electrode was investigated. And mechanism of photogenerated electron of PTh/CdSe electrode was proposed. The results showed that TiO2electrode modified by PTh/CdSe composite film had good response on irradiation, which indicated the PTh/CdSe was promising dye in solar cell.

Background Cataracts is considered be formed because of an abnormal glucose metabolic pathway or oxidative stress. We explored the damaging role of ONOO- and antagonism of cholecystokinin octapeptide-8 (CCK-8) in diabetic cataractal rat lenses. Methods A diabetic cataractal animal model was established by peritoneal injection of streptozotocine (STZ). Thirty-six normal SD rats were taken as control group; seventy-two were given STZ (45 mg/kg) and then divided into STZ group and CCK-8 group (peritoneal injection CCK-8). STZ induced diabetic rats were treated with CCK-8 for 60 days. Lenses were examined with slit lamp at 20, 40 and 60 days. Immunofluorescent staining and Western blot analysis were used for determining nitrotyrosine (NT, a marker for ONOO-). PT-PCR and gene array analysis were used for determining the expression of inducible nitric oxide synthetase mRNA (iNOS mRNA) in lens epithelium (LEC). Results STZ group rats developed lens opacity by 20 days that reached a high level by 60 days after STZ injection. CCK-8 group rats delayed the cataract formation. CCK-8 group rats delayed the cataract formation. There was no distinct expression of NT and iNOS mRNA in control group. In STZ group, there were distinct expression of NT and upregulation of iNOS mRNA; however, CCK-8 group showed weak expression of NT and downregulation of iNOS mRNA. Conclusions NT, which may be a new form of oxidative stress, was expressed in diabetic rat LEC although CCK-8 could reverse NT damage in LEC. The results suggested that CCK-8 might be a useful therapeutic agent against diabetic cataract. The antagonizing mechanism of CCK-8 may be related to direct antagonism of ONOO- as well as its inhibition of the expression of iNOS mRNA for production of NO and therefore decrease in the formation of ONOO-.

A MnOx-doped mesoporous activated carbon(AC-MnOx) and an activated carbon(AC) were prepared with and without Mn-containing additives.The microstructure and properties,such as pore volume,pore size distribution,iodine value and methylene blue value,were determined.The electrochemical performance of the two activated carbons as electrodes for electrochemical capacitors were characterized by cyclic voltammetry,AC impedance and charge-discharge at a constant current.Results show that the yield and iodine value of AC-MnOx are lowered by 28.9% and 12.4% respectively compared to AC.The methylene blue value of AC-MnOx is increased by 19.8% compared to AC.Moreover,AC-MnOx has more mesopores than does AC,especially in the range 3.4-4.2 nm.The specific capacitance of an AC-MnOx electrode is 93.8 F/g,which is 140% of that of an AC electrode,indicating that energy density and pseudo-capacitance of the AC-MnOx electrode are higher than those of AC electrode.