Cellular mechanics is a branch of tissue engineering and cellular engineering. As one of the important method, loading different mechanical stimuli to culturing cells in vitro so as to study the influence that the stress has on the cells is one of the important fields of cellular mechanics. This paper reviews the experimental methods for mechanically stimulating the cells in vitro, according to the different loading modalities, the methods can be categorized into micropipette aspiration, compression loading, substrate distention, fluid shear, etc. And it also points out their advantages and disadvantages.
Cell Culture Techniques ; Cells, Cultured ; Humans ; Stress, Mechanical ; Tissue Engineering

Objective To investigate intestinal cleaning status of the patients undergoing colonoscopy,and to analyze the potential influential factors.Methods A total of 340 patients undergoing colonoscopy in the endoscopy center of a Class Ⅲ Grade A hospital in Beijing from January to September 2017 were recruited into this study by convenience sampling method.The patients' general situation,disease condition,dietary and the implementation of bowel preparation were recorded.The intestinal cleaning status was scored according to the Boston Bowel Preparation Scale (BBPS).Results Of the 340 patients included in this study,67.9％ had adequate bowel preparation,and the other 32.1％ had not.Logistic regression analysis showed that male (OR=2.514),abdominal surgery history (OR=2.145),diabetes mellitus (OR=2.091),lunch at noon (OR=3.381) were the influential factors of intestinal cleanliness.Conclusions At present,the intestinal cleaning status is unsatisfactory.Medical staff should pay attention to male,patients with abdominal surgery history or diabetes mellitus,so as to have a better quality for the bowel preparation.

Objective:To investigate the effect of methylene blue (MB) on motor dysfunction and its mechanism in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) mouse models.Methods:Forty healthy male C57BL/6 mice were randomly divided into 4 groups: control group, model group, low-dose treatment group and medium-dose treatment group ( n=10); PD mouse models were established by intraperitoneal injection of 25 mg/kg/d MPTP for a consecutive 7 d; low-dose treatment group and medium-dose treatment group were pretreated intraperitoneally with MB 2 mg/kg/d or MB 10 mg/kg/d for a consecutive 3 d, respectively; and then, MPTP 25 mg/kg/d+MB 2 mg/kg/d or MPTP 25 mg/kg/d+MB 10 mg/kg/d were injected intraperitoneally into the low-dose treatment group or medium-dose treatment group for a consecutive 7 d (MPTP and MB were given at 12 h of interval). Eight d after modeling, open field experiment, pole climbing experiment and rod rotating experiment were carried out to evaluate the spontaneous movement, coordination, endurance and motor ability. And then, the mice were sacrificed; immunofluorescent staining was used to observe tyrosine hydroxylase (TH) expression in the substantia nigra; Western blotting was used to detect the expressions of TH, α-synuclein, nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), cleaved-Caspase-1 and Gasdermin D (GSDMD) in the striatum and substantia nigra of mice. Contents of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-18 in the substantia nigra and striatum of mice were detected by ELISA. Results:Compared with the control group, the model group had shortened residence time in rod rotating, prolonged descent time in rod climbing, reduced total movement distance in open field, decreased number of TH-positive cells in the substania nigra, decreased TH protein levels in the substania nigra and striatum, and increased NLRP3, ASC, cleaved-Caspase-1, GSDMD and GSDMD-N protein levels in the substania nigra and striatum, and increased TNF-α, IL-1β and IL-18 contents in the substania nigra and striatum, with significant differences ( P<0.05). Compared with the model group, low-dose treatment group and medium-dose treatment group had prolonged residence time in rod rotating, shortened descent time in rod climbing, increased total movement distance in open field, increased number of TH-positive cells in the substania nigra, and increased TH protein levels in the substania nigra and striatum, decreased NLRP3, ASC, and cleaved-Caspase-1 levels in the substania nigra and striatum, and decreased TNF-α, IL-1β and IL-18 contents in the substania nigra and striatum, with significant differences ( P<0.05). No statistical differences in the above indexes were noted between the low-dose treatment group and medium-dose treatment group ( P>0.05). Conclusion:Low-/medium-dose MB can ameliorate motor dysfunction in PD mouse models, whose mechanism may be related to downregulate NLRP3 inflammasome and inhibit neuroinflammatory response to reduce dopaminergic neuron pyroptosis.

For the detection and identification of abnormal nodular tissues on the body surface, a microwave sensor structure loaded with a spiral resonator is proposed in this paper, a sensor simulation model is established using HFSS software, the structural parameters are optimized, and the actual sensor is fabricated. The S21 parameters of the tissue were obtained when nodules appeared by simulation, and the characteristic relationship between the difference of S21 parameters with position was analyzed and tested experimentally. The results showed that when nodules were present in normal tissues, the curve of S21 parameter difference with position change had obvious inverted bimodal characteristics, and the extreme value of S21 parameter difference appeared when the sensor was directly above the nodules, which was easy to identify the position of nodules. It provides an objective detection tool for the identification of abnormal nodular tissues on the body surface.
Microwaves ; Recognition, Psychology ; Computer Simulation ; Software

Objective: To make a preliminary assessment on the immunogenicity of a quadrivalence recombinant human papillomavirus (HPV) vaccine (6, 11, 16 and 18 types) (Hansenulapolymorpha) in healthy women aged 18-45 years in phaseⅠclinical study. Methods: It was a single-center, double-blind, randomized, placebo-controlled phaseⅠ clinical study. Women aged 18-45 years were randomized (2∶1) to receive HPV vaccine (n=60) or placebo control (n=30) at months 0, 2 and 6. Antibodies against HPV6/11/16/18 were detected by pseudovirus-based neutralisation assay in serum samples collected at 0 d, 180 d and 210 d. Seroconversion rates and geometric mean titres (GMT) of antibodies against the four types of antigens were calculated. Results: Seroconversion rates of the vaccination group at 180 d (before the third dose) and 210 d (one month after the third dose) were generally similar and between 85%-100% for all types of antibodies. The GMT of antibodies at one month after the last dose improved significantly compared with those before immunization. Conclusions These results showed that the HPV vaccine had good immunogenicity in the population of healthy women aged 18-45 years. Higher antibody titers were elicited by the vaccine compare with the tites before the first dose and in the placebo control group.