Research progress of microRNA in diagnosis and treatment of pancreatic cancer / 国际肿瘤学杂志

MicroRNA (miRNA) plays a regulating function in translation stage of gene expression.MiRNA has been found directly involving in the occurrence and development of pancreatic cancer,and its abnormal expression is closely related to early diagnosis of pancreatic cancer and may provide new therapeutic target for pancreatic cancer patients.MiRNA detection will have good application prospect in on the diagnosis and treatment of pancreatic cancer.

Bio-detection techniques based on magnetic signal of nanoparticles / 生物医学工程学杂志

This article summarizes biological detection techniques based on magnetic signal of magnetic nanoparticles and the research progress of these techniques in biomedicine. Biological detection based on magnetic nanoparticles is faster, more accurate and more convenient compared to traditional optical techniques and causes much attention. It can be classified into giant magneto resistive biosensor (GMR), magnetic relaxation switch (based on T2 relaxation time), AC susceptibility (based on Brownian relaxation) and magnetic lateral flow immunoassay. These techniques can be combined with nanotechnology, microfluidics, immunoassay and bio-chips and have wide application prospects in clinical diagnosis, biological detection, environmental monitoring and food security areas.

Acute toxicity and irritation of water-based dextran-coated magnetic fluid injected in mice.

Based on the elements that magnetic nanoparticles could heat in an alternating magnetic field, magnetic fluid hyperthermia occurred to inhibit tumor growth in vivo. However, biocompatibility of those fluids as well as the fluid-body interaction remains unclear. In this article, acute toxicity and irritation of the water-based dextran-coated magnetic fluid (dextran-magnetic fluid) injected into mice subcutaneous tissues were examined. Lethal dosage 50 of single treatment with the magnetic fluid was 4409.61 +/- 514.93 mg/kg. When injected with 30 mg/0.3 mL dextran-magnetic fluid, activities of glutamicoxalacetictransaminase (AST) and glutamicpyruvictransaminase (ALT) and cell number of mice blood did not change statistically. Hemangiectasia and leucocytes infiltration were seen in subcutaneous tissues and these phenomena almost disappeared 72 h later. That is to say, the dextran-magnetic fluid was tolerable, safe, and biocompatible. The work is a basic for application of the dextran-magnetic fluid in subcutaneous tumor therapy.

Studies on the extraction of DNA using carboxyl-coated magnetic particles and quantification using fluorescent dye / 生物医学工程学杂志

Based on the study of extraction of DNA using carboxyl-coated Fe3O4, here we provide a rapid, high efficient, safe and economical method. Using fluorescent dye-Sybr Green I, the quantification of double-strand DNA exhibits the advantages of high sensitivity,good repeatability and convenience.

Study on the cell apoptosis induced by intracellular hyperthermia in human lung adenocarcinoma SPC-A1 cells / 生物医学工程学杂志

This is a comparative study on the efficacy of differential cell apoptosis induced by three methods (intracellular hyperthermia, with water bath hyperthermia and extracellular hyperthermia) in human lung adenocarcinoma SPC-A1 cells in vitro. The effects of hyperthermia on cell apoptosis were determined by Transmission electron microscopy(TEM), agarose gel electrophoresis and flow cytometry methods, respectively. The intracellular effect of particle heating was compared with that of water bath hyperthermia and extracellular hyperthermia; significant differences between these heating methods were detected, the rate of apoptosis being 36.59%, 5.66%, 7.78% respectively. When treated with intracellular hyperthermia, the SPC-A1 cells manifested typical morphological characters of apoptosis by TEM observation, and the SPC-A1 cell DNA was degraded into large fragments by agarose gel electrophoresis assay. Our results showed that amino-silane Fe3O4 induced intracellular hyperthermia was superior to water bath hyperthermia and extracellular hyperthermia. It is mainly the interaction between intracellular nanoparticles and cell that induced apoptosis. Therefore, the aminosilane-coated Fe3O4 may be used in hyperthermia or chemotherapeutics on cancer cells for further clinical application.

Security evaluation of subcutaneous injection with water-based dextran-coated magnetic fluid / 生物医学工程学杂志

Water-based magnetic fluid was synthesized by using 50% dextran 40,000 as coated reagent. The acute toxicity and irritant of the magnetic fluid injected into mice subcutaneous tissues were examined. The lethal dosage 50 of dextran-coated magnetic fluid was 4409.61 +/- 514.93 mg/kg. Twenty four h after subcutaneous injecting with 30 mg/0.3 ml dextran-coated magnetic fluid, no more inflammation than hemangiectasia and leucocytes infiltration had been seen in subcutaneous tissues, 72 h later the reaction phenomena disappeared. While, injection with 30 mg/0.3 ml water-based oleate sodium-coated magnetic fluid, ulceration and break-off of cutis had been seen in the seventh days. That is to say, the dextran-coated magnetic fluid was safe and well tolerate, however, the oleate sodium-coated magnetic fluid was not fit to subcutaneous injection.

Effect of temperature on concentration of active components extracted from medicinal herb / 中草药

Object To develop a mathematical model on the relationship between the temperature used in the course of extraction of medicinal herbs and the concentration of active component obtained Methods Based on the kinetic model on medicinal herb extraction process reported in our previous article *, diffusion coefficient and concentration gradient varying with temperature were further studied Results The process which tanshinone was extracted from Salvia miltiorrhiza Bge at different temperatures showed that the model could well match the experimental data Conclusion The relation between the temperature and the concentration of active component could be described by this model