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Background: Legionella is the causative agent of Legionnaires' disease, and hot springs are a major source of outbreaks of this disease. It is important from a public health perspective to survey hot spring environments for the presence of Legionella. Methods: Prospective surveillance of the extent of Legionella pollution was conducted at three hot spring recreational areas in Beijing, China in 2011. Pulsed-field gel electrophoresis (PFGE) and sequence-based typing (SBT) were used to describe the genetic polymorphism of isolates. The intracellular growth ability of the isolates was determined by interacting with J774 cells and plating the dilutions onto BCYE agar plates. Results: Overall, 51.9% of spring water samples showed Legionella-positive, and their concentrations ranged from 1 CFU/liter to 2,218 CFU/liter. The positive rates of Legionella were significantly associated with a free chlorine concentration of ≥0.2 mg/L, urea concentration of ≥0.05 mg/L, total microbial counts of ≥400 CFU/ml and total coliform of ≥3 MPN/L (p<0.01). The Legionella concentrations were significantly associated with sample temperature, pH, total microbial counts and total coliform (p<0.01). Legionella pneumophila was the most frequently isolated species (98.9%), and the isolated serogroups included serogroups 3 (25.3%), 6 (23.4%), 5 (19.2%), 1 (18.5%), 2 (10.2%), 8 (0.4%), 10 (0.8%), 9 (1.9%) and 12 (0.4%). Two hundred and twenty-eight isolates were analyzed by PFGE and 62 different patterns were obtained. Fifty-seven L. pneumophila isolates were selected for SBT analysis and divided into 35 different sequence types with 5 main clonal groups. All the 57 isolates had high intracellular growth ability. Conclusions: Our results demonstrated high prevalence and genetic polymorphism of Legionella in springs in Beijing, China, and the SBT and intracellular growth assay results suggested that the Legionella isolates of hot spring environments were pathogenic. Improved control and prevention strategies are urgently needed. [ABSTRACT FROM AUTHOR]

Composite coatings with hydroxyapatite (HA), octacalcium phosphate (OCP) in electrochemical deposition (ED) layers and MgO, Mg3(PO4)2 in microarc oxidation (MAO) layers were prepared by ED and MAO on Mg-Zn-Ca alloy to improve the corrosion resistance and bone response. Substrates and coated samples were implanted in the femur shaft of rabbits to observe in vivo degradation behavior during 50 weeks. Results showed that the degradation rate of the substrates was much faster than the coated at 8, 12 weeks and became close to the coated at 18 weeks postoperatively. The composite coatings prevented the substrate from rapid release of magnesium ions at the interface and gradually degraded at the same time. The composite coatings induced more newly formed bone tissue and faster bone response. Overall, reduced degradation rate and improved bone response were achieved by the composite coatings. Thus, the composite coatings on Mg-Zn-Ca alloy are promising for clinical application in the future. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 533-543, 2012. [ABSTRACT FROM AUTHOR]

Abstract: One-dimensional semiconductor nanostructures have demonstrated significant advantages for electrochemical electrode due to their remarkable size-dependent and structure-related properties. In this work, large-scale single-crystalline SnO2 nanowires have been successfully synthesized by thermal evaporation of a SnO2 and C powder under atmospheric conditions without any carrier gas or noble metal catalysts-coated substrate. The as-prepared samples exhibit uniform morphology with a thin diameter of 100–200 nm and length up to several tens of micrometers. The SnO2 nanowires directly grown on the initially deposition layer are found to grow along [301] direction, which is possibly dominated by a vapor–solid (VS) mechanism. The SnO2 nanowires synthesized by this simple and cheap method deliver a very high lithium storage capacity with good cycle stability and high rate capability, allowing for the achievement of high energy density and long cycle life for the next-generation energy conversion and storage devices. [Copyright &y& Elsevier]

Abstract: Perovskite strontium stannate (SrSnO3) nanorods were prepared by annealing the precursor SnSr(OH)6 nanorods at 600°C for 3h. The precursor nanorods were hydrothermally synthesized at 160°C for 16h using Sr(NO3)2 and SnCl4·5H2O as starting materials in the presence of surfactant cetyltrimethyl ammonium bromide (CTAB). As-prepared samples were characterized by X-ray diffraction (XRD), thermogravimetric-differential thermal analysis (TG-DTA), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and infrared ray spectroscopy (IR). The results show that the as-synthesized powders are made of SrSnO3 one-dimensional nanorods of about 0.2–1μm length and 100–150nm diameter. Possible formation mechanism of SrSnO3 with nanorod structure under certain conditions was preliminarily analyzed, in which it was thought that CTAB played an important role in the formation process of the nanorod structure. Electrochemical performance of the samples versus Li metal was also evaluated for possible use in lithium-ion batteries. [Copyright &y& Elsevier]

Abstract: A novel CuO-nanotubes/SnO2 composite was prepared by a facile solution method and its electrochemical properties were investigated as the anode material for Li-ion battery. The as-prepared composite consisted of monoclinic-phase CuO-nanotubes and cassiterite structure SnO2 nanoparticles, in which SnO2 nanoparticles were dramatically decorated on the CuO-nanotubes. The composite showed higher reversible capacity, better durability and high rate performance than the pure SnO2. The better electrochemical performance could be attributed to the introducing of the CuO-nanotubes. It was found that the CuO-nanotubes were reduced to metallic Cu in the first discharge cycle, which can retain tube structure of the CuO-nanotubes as a tube buffer to alleviate the volume expansion of SnO2 during cycling and act as a good conductor to improve the electrical conductivity of the electrodes. [Copyright &y& Elsevier]

What Is Already Known About This Topic?: Typhoid fever remains a major public health problem in developing countries. Waterborne typhoid fever affects an estimated 27 million people worldwide each year. Decades of indiscriminate antibiotic usage has driven the emergence and spread of multidrug-resistant (MDR) and even extensively drug-resistant (XDR) Salmonella Typhi ( S. Typhi) strains., What Is Added by This Report?: By combining the epidemiological investigations, bacterial isolation from patients and household water, whole genome sequencing and drug resistance analysis, we identified a waterborne typhoid fever outbreak caused by XDR S. Typhi in Beijing municipality. This was the first report of the XDR S . Typhi triggered outbreak in Beijing, which was also rare in China., What Are the Implications for Public Health Practice?: This report highlights the importance of ensuring access to affordable and safe drinking water, improved sanitation, and waste management systems for resource-constrained urban populations. Typhoid fever caused by XDR S . Typhi is still a severe public health threat., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2022.)

Objective: To investigate the effectiveness and surgical skills of microsurgical repair of radial nerve deep branch injury., Methods: Between March 2001 and February 2011, 49 cases of radial nerve deep branch injury were treated by microsurgical technique. There were 40 males and 9 females with an average age of 32 years (range, 19-58 years), including 13 cases of knife-cut injury, 9 cases of electric-saw injury, 7 cases of dagger-stab injury, 6 cases of glass-cut injury, 5 cases of iatrogenic injury, 4 cases of Monteggia fracture, 3 cases of nailgun injury, and 2 cases of crush injury of the forearm complicated by fracture of the proximal radius. The disease duration ranged from 3 hours to 3 years and 8 months (mean, 4.9 months). The sites of injury were at front of supinator tube in 15 cases, in the supinator tube in 23 cases, and at back of supinator tube in 11 cases. One-stage repair was performed by end-to-end suture in 21 cases, including 9 cases of epineurial neurorrhaphy and 12 cases of perineurial neurorrhaphy; two-stage repair was performed in 28 cases, including 26 cases of sural nerve graft and 2 cases of neurolysis., Results: Postoperative wounds primarily healed. All patients were followed up 21.5 months on average (range, 12-39 months). At last follow-up, in 21 cases of one-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 13 cases, and level 4 in 8 cases; in 28 cases of two-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 2 cases, level 4 in 21 cases, level 3 in 4 cases, and level 2 in 1 case; and significant difference was found (Z=-5.340, P=0.000). In 9 cases undergoing epineurial neurorrhaphy at one-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 3 cases, and level 4 in 6 cases; in 12 cases undergoing perineurial neurorrhaphy at one-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 10 cases, and level 4 in 2 cases; and significant difference was found (Z=-2.279, P=0.023). In 26 cases undergoing nerve graft at two-stage repair, the muscle strength of the extensor pollicis longus was level 5 in 2 cases, level 4 in 20 cases, level 3 in 3 cases, and level 2 in 1 case; in 2 cases undergoing neurolysis at two-stage repair, the muscle strength of the extensor pollicis longus was level 4 in 1 case and level 3 in 1 case; and no significant difference was found (Z=-1.117, P=0.264). According to the upper arm function assessment criterion issued by Hand Surgery Association of Chinese Medicine Association, the results were excellent in 18 cases, good in 3 cases in one-stage repair patients; excellent in 2 cases, good in 21 cases, fair in 4 cases, and poor in 1 case in two-stage repair patients; and there was significant difference (Z=-5.340, P=0.000)., Conclusion: Microsurgical one-stage repair of radial nerve deep branch injury can obtain better effectiveness than two-stage repair by nerve graft, and perineurial neurorrhaphy is significantly better than epineurial neurorrhaphy.