Development of Integrated Atomic Force Microscopy and Fluorescence Microscopy for Single-Molecule Analysis in Living Cells / 分析化学

Atomic force microscope ( AFM) and fluorescence microscope ( FM) have been emerging as two most commonly used tools for single-molecule study in living cells. Combining the advantages of two microscopes, the development of the integrated AFM-FM technique with high spatiotemporal resolution and multi-function has attracted increasing interest. In this review, the principles of AFM single-molecular force spectroscopy and single-molecule fluorescence imaging were briefly discussed, and the recent advances in the integrated AFM-FM instrumentation were summarized. Subsequently based on our own research in the investigation of ligand-receptors interactions with the integrated AFM-FM technique, its applications in live-cell single-molecule imaging and characterization were introduced.

Reconstruction of Digital Skin Defects with the Free Wrist Crease Flap.

BACKGROUND: Soft-tissue digital defects frequently need to be covered by a flap rather than a skin graft. In hand surgery, functional preservation and aesthetic appearance are often as important as procedural efficacy. OBJECTIVE: We present our clinical experience with reconstruction of digital skin defects with the free wrist crease flap. METHODS: From January 2012 to September 2013, 14 digits of 14 patients (10 males, 4 females) were included for evaluation. The procedure was performed with brachial plexus block anesthesia. The superficial palmar branch of the radial artery, a subcutaneous superficial vein, and the palmar cutaneous branch of the median nerve were included in the free wrist crease flap. The flaps were used to reconstruct the skin defect of injured digits through microvascular anastomosis, and donor sites were closed primarily. RESULTS: Postoperative follow-up time ranged from 3 to 25 months. All digital deformities were corrected, all flaps survived completely without ischemia, and none were aesthetically bulky. The area of free wrist crease flaps ranged from 2.5 to 5.0 cm by 2.0 to 3.1 cm. Slight wound infections appeared in two cases. Venous crisis occurred in one case, but it was successfully addressed after vascular exploration and reanastomosis. Sensation determined by static two-point discrimination measured in these flaps 2 months postsurgery was "good" at a mean 9.7 ± 2.1 mm (range, 6-14 mm). The mean motion range of the distal interphalangeal joint and proximal interphalangeal joint was 23.4 ± 6.9 degrees (0-42 degrees) and 75.8 ± 22.1 degrees (0-98 degrees) preoperatively. The mean motion range of the distal interphalangeal joint recovered to 40.3 ± 5.7 degrees (36-42 degrees), and that of the proximal interphalangeal joint was 90.3 ± 15.3 degrees (85-98 degrees) postoperatively. Both joints reached normal motion angle and difference was statistically significant preoperatively and postoperatively (p < 0.05). The mean disabilities of arm and shoulder (DASH) score was 6.8 ± 3.4 (0-15), and there was statistically significant difference when compared with the preoperative score of 13.5 ± 4.3 (3-19) (p < 0.05). CONCLUSION: We found the free wrist crease flap to be an ideal solution for reconstruction of skin defects of digits.

T-shaped excision of the orbicularis oris muscle: an innovative technique for upper lip lift procedures.

BACKGROUND: The lips are a prominent part of the face and they age along with the face. Microsurgery for upper lip lifts is becoming popular because of its association with minimal trauma and rapid recovery. OBJECTIVES: The authors introduced an innovative method of lifting the upper lip. METHODS: From January 2009 to March 2013, a cohort of 30 women underwent an upper lip lift surgical procedure. Patients received local anesthesia for a regional block of the infraorbital nerve. A T-shaped orbicularis oris and a strip of skin were excised. The superior edge of the orbicularis oris muscle was sutured to the base of the nose, and the incision was closed with a continuous intradermal suture. Postoperative follow-up time ranged from 1 to 5 years. RESULTS: At the time of follow-up, the incisional scar was not visible on the patient. The nasolabial angle was 96.20° ± 1.86° before operation and 88.23° ± 2.58° after operation. The difference was statistically significant (P = 0.000 and P < 0.001). The upper lip angle was 65.56° ± 8.60° before operation and 51.90° ± 3.93° after operation. The difference was statistically significant (P = 0.000) and P < 0.001). After operation, the upper lip appeared to be clearly thickened. CONCLUSIONS: This innovative surgical technique is a simple and effective way to lift the upper lip.

A comparison of skin expansion and contraction between one expander and two expanders: a preliminary study.

BACKGROUND: This study aimed to compare the difference between the skin expansion and contraction rates for an expanded flap with one versus two expanders. METHODS: The study cohort comprised 24 cases of two overlapping expanders and 15 cases of a single implanted expander involving 22 patients. The method of "wet-cloth sampling" was applied to measure the expanded flap area and the initial unexpanded area and to calculate the skin expansion rate. Two points 5 cm apart in the center of the expanded flap were selected before the second surgical stage. After removal of the expander, the distance between the two fixed points was measured and recorded. The contraction rate of the expanded flap then was calculated. RESULTS: During the same period of expansion in the two groups (p = 0.06, >0.01), the skin expansion rate was 3.5 ± 0.9 % in the group with two overlapping expanders and 2.6 ± 0.6 % in the control group. The difference between the two groups was statistically significant (p = 0.002, <0.05). The instantly expanded flap contraction rates were 30.3 ± 0.8 and 32.3 ± 0.9 %, respectively for the two groups, and the difference was not statistically significant (p = 0.47, >0.05). We fitted a linear regression model that was Y = 0.533 − 0.003X, where Y was the contraction rate of the expanded flap and X was the period of expansion. The contraction rate of the expanded flap was negatively correlated with the period of expansion. CONCLUSIONS: Compared with the traditional method of implanting a single expander, the new method of overlapping two expanders in a single cavity increased the skin expansion rate. The instantly expanded flap contraction rate did not differ significantly between the two groups, so the amount of expanded skin area absolutely increased. The clinical application of the new method is worth promoting. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.