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Super-resolution fluorescence microscopy has emerged as a powerful tool for studying mitochondrial dynamics in living cells. However, the lack of photostable and chemstable probe makes long-term super-resolution imaging of mitochondria still a challenging work. Herein, we reported a 4-azetidinyl-naphthliamide derived SNAP-tag probe AN-BG exhibiting excellent fluorogenicity and photostability for long-term super-resolution imaging of mitochondrial dynamics. The azetidinyl group and naphthalimide fluorophore are in a flat conformation which can effectively suppress twisted intramolecular charge transfer and then effectively improve the brightness and photostability. This planarized molecular structure is conducive to the formation of fluorescence-quenched J-aggregates, and the protein labeling process will depolymerize the probes and restore fluorescence. Fluorescent labeling mitochondrial inner membrane proteins via SNAP tags overcomes the shortcomings that variations in mitochondrial inner membrane potential will release probes attached to mitochondria by electrostatic interactions. Therefore, AN-BG realized the stable labeling of mitochondria and the long-term imaging of mitochondrial dynamics under super-resolution microscopy.

To explore the clinical efficacy and safety of microscopy-assisted anterior corpectomy and fusion for cervical ossification of the posterior longitudinal ligament (OPLL). A retrospective review of 32 cervical OPLL patients who underwent microscopy-assisted anterior corpectomy and fusion from June 2012 to March 2017 was carried out. Patients were evaluated with outcome metrics: Japanese Orthopaedic Association (JOA) scores (17 points method), visual analog scale (VAS), and radiographic parameters of the lordotic angle. The complications during treatment and follow-up were recorded. This study included 32 patients (15 males and 17 females) with a mean age of 58.3 ± 2.9 years (range 42–68 years). The average duration of follow-up was 19.0 ± 3.5 months (range 11–46 months). The scores of postoperative VAS significantly decreased (P

An electrostatic force microscope (EFM) was used to characterize single-walled carbon nanotube (SWNT)-based nanoswitches in this paper. A conductive atomic force microscopy (AFM) tip acted as a mechanical probe as well as a positioning electrode in the experiment. The resonance frequency of the SWNT beams was computed from the measured SWNTs' dimension and spring constant. The pull-in voltages and the corresponding gaps were extracted simultaneously from a set of force curves at different EFM probe bias voltages. The adhesive force between the AFM tip and the SWNT beam was measured through the analysis of retract force curves. The relationship between the pull-in voltage and the SWNT nanoswitch gap was in agreement with the electrostatic pull-in theory. Long-range forces such as meniscus force or electrostatic force from surface charges engaged the SWNT beam when the gap was below 6 nm in atmosphere. The SWNT beam with a resonance frequency of 1.1 GHz was actuated by a voltage of 2 V for a gap of 6.5 nm. The average adhesive force between an SWNT beam and a platinum/iridium (PtIr5)-coated tip was found to be about 50 nN. Considering the stiffness of the 1.1 GHz SWNT beam, the elastic restoring force at 6.5 nm exceeds 53 nN, which will overcome the adhesive force and release the 1.1 GHz SWNT beam. Finally, some possible approaches to further improve the behavior of SWNT nanoswitches are discussed.