Biocompatibility of marine magnetotactic ovoid strain MO-1 for in vivo application

Magnetotactic bacteria are capable of biosynthesizing magnetic nanoparticles,also called magnetosomes,and swimming along magnetic field lines.The abilities endow the whole cells of magnetotactic bacteria with such applications as targeted therapy and manipulation of microrobots.We have shown that the intact marine magnetotactic bacteria MO-1 kill efficiently antibiotic-resistant pathogen Staphylococcus aureus in vivo,but the biocompatibility of this marine bacterium is unknown.In this study,the strain MO-1 was chosen to analyze its biocompatibility and potential for biomedicine applications.Results showed that MO-1 cells could be guided at 37℃ under an external magnetic field and swim in the blood plasma and urine.They could keep active locomotivity within 40 min in the plasma and urine,although their velocity slowed down.When incubated with human cells,magnetotactic bacteria MO-1 had no obvious effects on cellular viability at low dose,while the cell toxicity increased with the augmentation of the quantity of the MO-1 cells added.In the in-vivo experiments,the median lethal dose of magnetotactic bacteria MO-1 in rats was determined to be 7.9×10^(10) bacteria/kg.These results provided the foundation for the biocompatibility and safety evaluations of magnetotactic bacteria MO-1 and suggested that they could be basically used in clinical targeted therapy.

Design and application of computer software for collecting color data about urine reagent strips

Urine analysis is one of the most common and useful assay means in clinic for diagnose disease, especially urinary system disease and dry chemistry method is the most convenient, common and low cost about urine analysis. To expediently and efficiently analyze the corresponding relationships between different color data and semi-quantitative results about every urine item with dry chemistry way, in this paper, the design and application of effective software that may be used to collect color data about urine reagent strips are presented. First, we introduce the design procedure of this software. Second, its realization of design is given. Third, several application examples about collecting RGB original data by RS232 interface are shown. Then, RGB original data can be visually displayed by waveforms or curves and the data of cursor position may also be given. From the examples, we could confidently draw a conclusion that it is very convenient and effective to study on the laws of color variation about reagent pieces on reagent strip and it has met our original designed demands.

Preparation of pyrido[1,2-c][1,2,4]triazole-based π-conjugated triazene as a Fe3+ ion fluorescent sensor

A highly efficient coupling reaction of N-heterocyclic carbene precursors with sulfonyl azides has been developed, affording a variety of pyrido[1,2-c][1,2,4]triazole-based π-conjugated triazenes. The present reaction proceeds under very mild conditions with good functional group tolerance. The resulting triazenes exhibit selective and sensitive fluorescent response toward Fe3+ion.