BRCAA1 monoclonal antibody conjugated fluorescent magnetic nanoparticles for in vivo targeted magnetofluorescent imaging of gastric cancer

<p>Abstract</p> <p>Background</p> <p>Gastric cancer is 2th most common cancer in China, and is still the second most common cause of cancer-related death in the world. How to recognize early gastric cancer cells is still a great challenge for early diagnosis and therapy of patients with gastric cancer. This study is aimed to develop one kind of multifunctional nanoprobes for <it>in vivo </it>targeted magnetofluorescent imaging of gastric cancer.</p> <p>Methods</p> <p>BRCAA1 monoclonal antibody was prepared, was used as first antibody to stain 50 pairs of specimens of gastric cancer and control normal gastric mucous tissues, and conjugated with fluorescent magnetic nanoparticles with 50 nm in diameter, the resultant BRCAA1-conjugated fluorescent magnetic nanoprobes were characterized by transmission electron microscopy and photoluminescence spectrometry, as-prepared nanoprobes were incubated with gastric cancer MGC803 cells, and were injected into mice model loaded with gastric cancer of 5 mm in diameter via tail vein, and then were imaged by fluorescence optical imaging and magnetic resonance imaging, their biodistribution was investigated. The tissue slices were observed by fluorescent microscopy, and the important organs such as heart, lung, kidney, brain and liver were analyzed by hematoxylin and eosin (HE) stain method.</p> <p>Results</p> <p>BRCAA1 monoclonal antibody was successfully prepared, BRCAA1 protein exhibited over-expression in 64% gastric cancer tissues, no expression in control normal gastric mucous tissues, there exists statistical difference between two groups (<it>P </it>< 0.01). The BRCAA1-conjugated fluorescent magnetic nanoprobes exhibit very low-toxicity, lower magnetic intensity and lower fluorescent intensity with peak-blue-shift than pure FMNPs, could be endocytosed by gastric cancer MGC803 cells, could target <it>in vivo </it>gastric cancer tissues loaded by mice, and could be used to image gastric cancer tissues by fluorescent imaging and magnetic resonance imaging, and mainly distributed in local gastric cancer tissues within 12 h post-injection. HE stain analysis showed that no obvious damages were observed in important organs.</p> <p>Conclusions</p> <p>The high-performance BRCAA1 monoclonal antibody-conjugated fluorescent magnetic nanoparticles can target <it>in vivo </it>gastric cancer cells, can be used for simultaneous magnetofluorescent imaging, and may have great potential in applications such as dual-model imaging and local thermal therapy of early gastric cancer in near future.</p

Original Investigation The Role of Sulfadiazine for the Treatment of Refractory Intracranial Infection Dirençli İntrakranial Enfeksiyon Tedavisinde Sülfodiazin&apos;in Rolü

ABSTRACT AIm: Sulfadiazine (SD) is a classic antibiotic for intracranial infection. Due to the medical market policy, SD has not been chosen as an essential drug in all the hospitals in China. However, its therapeutic effect is definite and cannot be substituted. The aim of this study was to evaluate the therapeutic and economic value of SD compared to other popular antibiotics in patients with refractory intracranial infection. mAterIAl and methOds: A retrospective single-center study was performed from January 2011 until December 2012. Thirteen patients diagnosed with refractory intracranial infection were treated with SD. The clinical effects were reviewed. results: Treatment was successful for 12 of the patients (cure rate=92.3%). One patient died of secondary epilepsy, respiratory complications, and multiple organ failure. Only one patient was allergic to SD, and there were no drug-related liver or kidney side effects. COnClusIOn: SD is a safe, effective, and economical antibiotic, and is used by our neurosurgical department. It should be offered as an option for the patients with refractory intracranial infection, especially for patients with lower ability to pay

Green catalytic synthesis of 5-methylfurfural by selective hydrogenolysis of 5-hydroxymethylfurfural over size-controlled Pd nanoparticle catalysts

A green approach for the conversion of 5-(hydroxymethyl) furfural (HMF) to 5-methylfurfural (MF) by using size-controlled palladium catalysts has been developed. Palladium nanoparticles (Pd NPs) with various sizes supported on activated carbon were prepared with polyvinylpyrrolidone (PVP) as the capping agent. The reaction results showed that all the PVP-assisted Pd catalysts achieved high selectivity whilst the hydrogenation ability of Pd NPs could be rationally tuned by varying the mole ratio of Pd/PVP. 2.5% Pd-PVP/C (1 : 2) presented a satisfactory activity with 80% MF yield and 90% selectivity. The reaction kinetics study showed that the transformation of HMF into MF over bifunctional PVP-assisted Pd NPs underwent an acid-catalyzed esterification followed by a Pd-catalyzed hydrogenolysis procedure. The role of formic acid in the transformation is not only as a hydrogen-donating agent but also as a reactant to form the key intermediate. This work provides a novel and environmentally-friendly method for the selective hydrogenation of bio-based HMF to MF

Magnetic multilayers on nanospheres

Thin-film technology is widely implemented in numerous applications. Although flat substrates are commonly used, we report on the advantages of using curved surfaces as a substrate. The curvature induces a lateral film-thickness variation that allows alteration of the properties of the deposited material. Based on this concept, a variety of implementations in materials science can be expected. As an example, a topographic pattern formed of spherical nanoparticles is combined with magnetic multilayer fi lm deposition. Here we show that this combination leads to a new class of magnetic material with a unique combination of remarkable properties: The so-formed nanostructures are monodisperse, magnetically isolated, single-domain, and reveal a uniform magnetic anisotropy with an unexpected switching behaviour induced by their spherical shape. Furthermore, changing the deposition angle with respect to the particle ensemble allows tailoring of the orientation of the magnetic anisotropy, which results in tilted nanostructure material