[Clinical features, diagnosis and treatment of 5 cases of primary pneumonic plague in Tibet in 2010].

OBJECTIVE: To explore the clinical manifestations, the feature of chest X-ray, the clinical outcome, and the clinical treatments of severe pneumonic plague. METHODS: We observed the clinical course of primary pneumonic plague in 5 patients, who infected Yersinia pestis in Tibet during September 2010, including manifestations of chest X-ray, the antibiotic therapy, respiratory support and the prognosis. RESULTS: All of the 5 patients presented with high fever, bloody sputum and difficulty breathing. The chest X-ray showed signs consistent with necrotizing inflammation with multiple lobar involvement. Mass-like lesions might coalesce, and the "white lung" sign might appear. Three out of the 5 patients presented with hypoxemia. The results of reverse indirect hemagglutination assay (RIHA) in these patients were positive on the second day of the illness onset. All of these patients recovered after antibiotic therapy and other treatments. However, the absorption of lung lesions was very slow. CONCLUSIONS: Patients infected with primary pneumonic plague presented with rapid onset high fever and hemoptysis, and the lung injury was very severe. The positive result of RIHA was useful for early diagnosis of plague. Streptomycin should be the first choice for Yersinia pestis infection, but its optimal dose needed further study. Fluoroquinolones can be used as combination with Streptomycin. Nutritional support and symptomatic treatment, as well as non-invasive or invasive mechanical ventilation when needed, were important for the management of the disease.

[Determination of mercury in Chinese medicinal material and biological samples using pyrolysis atomic absorption spectrometry].

In this paper a rapid and simple method using pyrolysis coupled with atomic absorption spectrometry for the analysis of total mercury in Chinese medicinal material and biological samples is presented. No sample digestion was needed and this greatly simplifies the analytical procedure and minimizes potential sources of contamination. Under optimum conditions, the reproducibility of the method was 2.1% for peak area and 9.1% for peak height. The detection limit (3sigma) was 6.3 ng x g(-1), and the recovery was within the range of 95%-105%. Several standard reference materials were analyzed and the results were obtained with satisfaction. The performance of the method was compared with inductively coupled plasma-mass spectrometry (ICP-MS), and excellent agreements were observed between these two methods.

Surface molecularly imprinted nanowires for biorecognition.

Herein we present a novel method for preparation of surface molecularly imprinted size-monodisperse nanowires. The imprint molecule is immobilized on the pore walls of a silane-treated nanoporous alumina membrane. The nanopores are then filled with the monomer mixture, and the polymerization is initiated. The alumina membrane is subsequently removed by chemical dissolution, leaving behind polypyrrole nanowires with glutamic acid binding sites situated at the surface. These nanowires can be dissolved in aqueous media, and their applications therefore should be compatible with procedures in which biological antibodies might otherwise be used. For example, the analyte molecule can be tagged with various markers, such as fluorescence probes and enzymes, whereby the problem of steric hindrance is avoided. Furthermore, these surface-imprinted nanowires are likely suited for imprinting and recognition of large-molecular-weight peptides and proteins. Related work is currently being undertaken in our laboratory.

Magnetite-containing spherical silica nanoparticles for biocatalysis and bioseparations.

The simultaneous entrapment of biological macromolecules and nanostructured silica-coated magnetite in sol-gel materials using a reverse-micelle technique leads to a bioactive, mechanically stable, nanometer-sized, and magnetically separable particles. These spherical particles have a typical diameter of 53 +/- 4 nm, a large surface area of 330 m(2)/g, an average pore diameter of 1.5 nm, a total pore volume of 1.427 cm(3)/g and a saturated magnetization (M(S)) of 3.2 emu/g. Peroxidase entrapped in these particles shows Michaelis-Mentan kinetics and high activity. The catalytic reaction will take place immediately after adding these particles to the reaction solution. These enzyme entrapping particles catalysts can be easily separated from the reaction mixture by simply using an external magnetic field. Experiments have proved that these catalysts have a long-term stability toward temperature and pH change, as compared to free enzyme molecules. To further prove the application of this novel magnetic biomaterial in analytical chemistry, a magnetic-separation immunoassay system was also developed for the quantitative determination of gentamicin. The calibration for gentamicin has a working range of 200-4000 ng/mL, with a detection limit of 160 ng/mL, which is close to that of the fluorescent polarization immunoassay (FPIA) using the same reactants.

Molecularly imprinted sol-gel nanotubes membrane for biochemical separations.

In this study, we report a simple procedure for applying molecular imprinting functional groups to the inner surfaces of the template-synthesized sol-gel nanotubes for chemical separation of estrone. The silica nanotubes were synthesized within the pores of nanopore alumina template membranes using a sol-gel method by simultaneous hydrolysis of a silica monomer-imprinted molecule complex and tetraethoxysilane (TEOS). A covalent imprinting strategy was employed by generating a sacrificial spacer through the reaction of the isocyanate group of 3-(triethoxysilyl)propyl isocyanate and a phenol moiety of estrone to form a thermally cleavable urethane bond. This allowed us to remove the imprinted estrone by simple thermal reaction and to simultaneously introduce functional groups into the cavity formed by the silica nanotubes. Experiments indicated that estrone could be bound selectively by such an approach and have a binding affinity of 864 +/- 137 (n = 3).