Study designA prospective clinical study assessing new vertebral compression fracture after previous treatment.ObjectiveThe purpose of this study was to investigate the incidence and associated risk factors of new symptomatic osteoporotic vertebral compression fractures (OVCFs) in patients treated by percutaneous vertebroplasty (PVP) and kyphoplasty (PKP) versus conservative treatment, and to elucidate our findings.Summary of background dataThere are a lot of reports concerning the feasibility and efficacy of this minimally invasive procedure compared with conservative treatment, especially in pain soothing. However, it is still unclear whether the risk of subsequent fracture has increased among operative treatment patients in the long term.MethodsFrom November 2005 to July 2009, 290 consecutive patients with 363 OVCFs were randomly selected for PVP/PKP or conservative treatment and evaluated with a mean follow-up of 49.4 months (36–80 months). Some parameters were characterized and statistically compared in this study. Telephone questionnaires, clinical reexamine, and plain radiographs were performed in the follow-up.ResultsThirty-one of 290 (10.7 %) patients had experienced 42 newly developed symptomatic secondary OVCFs. Among 169 operation (53.3 % vertebroplasty, 46.7 % kyphoplasty) and 121 comparison patients, there is no significant statistical difference of new OVCFs incidence between the two groups calculated by patient proportion. However, in separate, the rate of secondary adjacent fractures calculated by vertebral refracture number is significantly higher than non-adjacent levels in PVP/PKP group but no significant statistical difference was observed in conservative group. The time interval of recompression after operative procedure was much shorter than that for comparison group (9.7 ± 17.8 versus 22.4 ± 7.99 months, p = 0.017). In addition, older age, gender, fracture times, location of original fracture segment, the amount of cement, cement leakage, operation modality (PVP or PKP),and initial number of OVCFs were documented, but these were not the influencing factors in this study (p > 0.05).Conclusions Patients who had experienced PVP/PKP were not associated with an increased risk of recompression in new levels. However, recompression in new levels of PVP/PKP group occurred much sooner than that of conservative group in the follow-up period. The incidence of new vertebral fractures observed at adjacent levels was substantially higher but no sooner than at distant levels in PVP/PKP group. No major risk factors involving new OVCFs have been found in this study and  augmentation for sandwich situation is not necessary.

Micromotors are extensively applied in various fields, including cell separation, drug delivery and environmental protection. Micromotors with high speed and good biocompatibility are highly desirable. Bubble-driven micromotors, propelled by the recoil effect of bubbles ejection, show good performance of motility. The toxicity of concentrated hydrogen peroxide hampers their practical applications in many fields, especially biomedical ones. In this paper, the latest progress was reviewed in terms of constructing fast, bubble-driven micromotors which use biocompatible fuels, including low-concentration fuels, bioactive fluids, and enzymes. The geometry of spherical and tubular micromotors could be optimized to acquire good motility using a low-concentration fuel. Moreover, magnesium- and aluminum-incorporated micromotors move rapidly in water if the passivation layer is cleared in the reaction process. Metal micromotors demonstrate perfect motility in native acid without any external chemical fuel. Several kinds of enzymes, including catalase, glucose oxidase, and ureases were investigated to serve as an alternative to conventional catalysts. They can propel micromotors in dilute peroxide or in the absence of peroxide.

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PURPOSE. To determine the prevalence of fundus tessellation and associations with ocular and systemic parameters among junior students from Greater Beijing. METHODS. The school-based study included 1443 individuals with a mean age of 12.4 6 0.5 years (range: 9-16 years). All participants underwent a comprehensive ophthalmic examination and an interview. Fundus tessellation, defined as variation in the visibility of large choroidal vessels, was differentiated into three grades. RESULTS. The prevalence and degree of fundus tessellation were 688/1430 (48.1%; 95% confidence intervals [CI]: 45.5%, 50.7%) and 0.54 6 0.61 (median, 0.00; range, 0-3), respectively. In multivariable regression analysis, a higher degree of fundus tessellation was associated with reduced subfoveal choroidal thickness (P < 0.001; beta, À0.02; odds ratio [OR], 0.98; 95% CI: 0.98, 0.99) and longer axial length (