Abstract:The discovery of the DNA double helix structure has turned life science research into the molecular level, and the sequencing technology that emerged in the 1970s has made a great contribution to the deciphering of the genetic code. Single-molecule sequencing technology, also known as third-generation sequencing technology, which has appeared in recent years, can read nucleotide sequences at the single molecular level. The single-molecule sequencing systems mainly include HeliScope, Nanopore and PacBio. Compared to traditional first- and next-generation sequencing technologies, third-generation sequencing can produce longer reads, sequence RNA directly without reverse transcription, and the speed is extremely fast. Meanwhile the equipment of some systems can be miniaturized and portable for in-field sequencing. The third-generation sequencing technology has numerous applications in the basic theroretical research of life science and the clinical practice in biomedicine. This paper focuses on the principles, the pros and cons, and the research progress and applications, of various single-molecule sequencing methods.

Abstract:Gamma rhythm ranges from 30 to 80 Hz, widely existing in neocortex. The key condition for the generation of gamma rhythm is the participation of inhibitory interneuron network. Spontaneous gamma rhythm is mainly related to parvalbumin inhibitory interneurons. In mouse, cat and monkey V1, the induced gamma rhythm is mainly derived from laminar 2/3 and 4B, and are well tuned by grating parameters. In primary visual pathway of cat and mouse, the high frequency gamma rhythm induced by brightness is derived from retina. However, brightness evoked gamma oscillation in monkey was observed in V1, but was not recorded in LGN. Dendrite-targeting somatostatin interneurons are critical for a visually induced, context-dependent low gamma rhythm (20-40 Hz) in primary visual cortex. The visually induced high frequency gamma rhythm (65-80 Hz) was mainly associated with PV cells. Increases in background light intensity trigger proportional increases in narrowband gamma oscillations (55-65 Hz) of mouse early visual pathway, which originated from ipRGCs cells in the retina. The gamma rhythm is variable in different physiological state, development stage and brain disease, implying the change in the visual information processing.

Abstract:As a kind of mechanical vibration wave, ultrasonic has ripple effect, mechanical effect and thermal effect，all of which have significant application value in clinical. Thus it can be used for diagnosis of disease, auxiliary dosage, regulation and thermal ablation etc. Ultrasonic techniques of non-invasive, strong penetrating power and high spatial resolution characteristics, also make it is widely applied in the diagnosis and treatment of disease of the nervous system. Depression, a common psychiatric disorder, is facing great challenges in diagnosis and treatment. A large number of researchers have applied ultrasonic technology in depression. This review mainly summarized the application of ultrasonic technology in depression in recent ten years from the aspects of ultrasonic imaging, ultrasonic fixed-point drug delivery, ultrasonic regulation and ultrasound-induced depression, hoping to provide certain reference and help for the study of the pathogenesis, diagnosis and treatment of depression.

Abstract:The singing of songbirds is learned behavior. It is controlled by networks of discrete nuclei, called the song control system. Sex steroids affect singing behavior through regulating song control system. It was reported that sex steroids, especially androgens, play key roles in maintaining the stability of the birdsong. Androgens through modulating cell proliferation, electrophysiological properties, synaptic and receptors influence song control system. This paper reviews the research progress that androgen effect on singing behavior and neural mechanism in songbirds.

Abstract:Over the past decade, fibroblast activation protein (FAP), a type II transmembrane serine hydrolase, has been identified and investigated widely in multiple research fields, including biochemistry, pharmacy, clinical medicine, which plays a key role in the metabolism of multiple endogenous peptides and peptide drugs. With the researching of FAP on its physiological functions and the relationships between FAP and clinical diseases, the biological or pathological processes of FAP in normal human or FAP-related diseases has been more clearer. Besides of being a potential therapeutic target for the treatment of cancer, FAP also serves as diagnostic markers for some diseases such as tumor and rheumatoid arthritis. Therefore, a variety of FAP detection methods and inhibitors have been reported. Based on FAP structural features, catalytic properties, endogenous substrate characteristics and exogenous substrate preferences, tissue distribution and specificity, and biological functions, this review not only analyzed the advantages and disadvantages of current FAP detection methods (in vitro and in vivo) and inhibitors but also summarized the structural characteristics of FAP detection substrates and the potential structure-activity relationship of inhibitors. This review will provide an overview of reference values and important reference value for the development of FAP-specific detection methods and potent inhibitors.

Abstract:In the recent years, the microscopic magnetic resonance technology using nitrogen-vacancy (NV) centers in diamond as quantum sensors has been developed rapidly. The detection of magnetic resonance spectrum of a single biomolecule has been achieved, and it now steps to the study of single molecule’s structure and function. Therefore, it is necessary to solve an important technical problem: how to disperse and fix biomolecules on diamond surface orderly. DNA self-assembly provides a possible way to solve this problem. In this paper, 60 nm square double-layer DNA origami was prepared as a kind of single-molecule carrier and then combined to the diamond surface. Firstly, we used the double layer structure to enhance the DNA origami’s strength. Secondly, by adding hairpin structure to the edge of DNA origami, the agglomeration between DNA origami was reduced. Finally, the DNA origami was successfully assembled to the diamond surface. The atomic force microscope images showed that the structure was complete and the dispersion was uniform. This work built a foundation for the subsequent application of single-molecule magnetic resonance technology in the field of biophysics.

Abstract:Many domestic cell culture laboratories are plagued by “black granules” contamination, which are commonly referred to as “nanobacteria” contamination in foreign countries, but the species of “black granules” has not been determined. “Black granules” were isolated from DMEM medium, and 16 S rDNA sequencing and VITEK-2 microbial identification system were used for the classification and identification of “black granules”. Antibiotic susceptibility assay and crystal violet staining technique were used to screen the antibiotics sensitive to “black granules” and their suitable concentrations for cell culture. We observed that “black granules” were spotted or flaky with an inverted microscope. The “black granules” was rod-shaped, with a length of 1 300-1 600 nm and a width of 400-500 nm under the transmission electron microscope, and “Brownian motion” was performed in situ under confocal laser scanning microscope. The results of 16 S rDNA sequencing and VITEK-2 microbial identification system showed that “black granules” was a new strain of Brevundimonas, and its sequences were 97.8% similar to Brevundimonas diminuta as well as 98.1% similar to Brevendomonas faecalis, respectively. Antibiotic susceptibility assay showed that “black granules” were sensitive to antibiotics chloramphenicol (25 mg/L), erythromycin (200 mg/L) and tetracycline (2.5 mg/L), but resistant to ampicillin (50 mg/L), puromycin (2 mg/L), penicillin-streptomycin (100×) or gentamicin-amphotericin B (100×). Crystal violet staining showed that the proliferation of “black granules” was inhibited by the chloramphenicol (25 mg/L), erythromycin (200 mg/L) or tetracycline (2.5 mg/L) in the DMEM medium, and the inhibition of “black granules” for cell proliferation were reduced. In summary, the “black granules” isolated and identified in our study was a new stain of Brevundimonas, and the inhibition of “black granules” for cell proliferation could be reduced by low concentration of chloramphenicol, erythromycin or tetracycline. Due to the limitations of this study, there may be other possibilities for the species of “black granules”. This study provides new research ideas and methods for species identification of “black granules” or nanobacteria and sterile culture of cells.