Different interactions between the two sides of purple membrane with atomic force microscope tip.

Atomic force microscopy (AFM) is known to be capable of measuring local surface charge density based on the DLVO model. However, it has failed to distinguish charge density difference between the extracellular and cytoplasmic sides of purple membrane (PM) in previous studies. In this paper, tapping-mode AFM with thioglycolate-modified tips was used to image PM in buffers of different salt concentrations.

[Study on synergic or antagonistic effects of different acupoint groups on vertebro-basilar insufficiency].

Objective: To observe the synergic or antagonistic effect of needling acupoints Fengchi (GB 20) and Tianzhu (BL 10), and Jiaji C4-C6 (EX-B2) on vertebro-basilar insufficiency (VBI).

Methods: Self-control method was used and 20 cases of VBI were respectively treated with acupuncture at Fengchi (GB 20) and Tianzhu (BL 10), Jiaji (EX-B2). Their combination and the changes of vertebro-basilar artery's (VBA) systolic velocity of blood flow was detected.

Preliminarily investigating the polymorphism of self-organized actin filament in vitro by atomic force microscope.

With the atomic force microscope (AFM), we preliminarily investigated the large-scale structure of actin filaments formed in low concentration protein solution (5 microg/ml) via self-organization without the presence of any F-actin dynamic interfering factors (such as phalloidin) in vitro. It was found that the G-actin could be polymerized into ordered filamentous structures with different diameter from the slimmest filament of single F-actin to giant filament in tree-like branched aggregates. The observed polymerized actin filaments, to which our most intense attention was attracted, was discretely distributed and showed obvious polymorphism distinctly different from those in the presence of phalloidin or actin binding proteins (fimbrin, gelsolin, etc.