BACKGROUND:There is no clear conclusion on whether the lung cancer stem cels can induce to spheroid formation and have tumorigenicity. OBJECTIVE: To observe the spheroid formation induced by human lung adenocarcinoma cel line SPC-A1 and the tumorigenic ability of lung cancer stem cels. METHODS:SPC-A1 at proliferating phase was cultured in serum-free DF12 culture medium, and then recombinant human insulin-like growth factor-1, recombinant human epidermal growth factor, and recombinant human fibroblast growth factor-10 were added to induce spheroid cels. Immune fluorescence detection and PCR amplification were done to understand the expression of stem cel associated markers. NOD-SCID immunodeficient mice were subcutaneously implanted with lung spheroid cels to observe the tumor growth.In vivo fluorescence imager was used for radiography. RESULTS AND CONCLUSION:After 5-10 days, lung spheroid cels were harvested. RT-PCR results showed that lung spheroid cels were positive for CD24, CD221, CCSP and SP-C. In addition, the lung spheroid cels and purified CD24+, CD221+ lung cancer stem cels were both positive for TTF-1 of lung stem cels, OCT4 and Nanog of embryonic stem cels and TTF-1 of Bmi-1 lung stem cels. The fluorescence detection showed that over 80% lung spheroid cels expressed CCSP and OCT4; SPC-A1 cels had the characteristics of alveolar type II cels, and also expressed SP-C protein, but only about 5% of the cels expressed CCSP and OCT4. At 50 days after subcutaneous implantation of lung spheroid cels, in vivo fluorescence imaging showed that the diameter of tumor in mice was 1 cm, indicating human lung adenocarcinoma cel line SPC-A1 can induce the spheroid formation, and lung cancer stem cels rich in the cel spheres have the tumorigenic ability.

This research adopted silt as the sample,and the five highest hydrogen production performing strains contained in the sample were isolated. The strain whose hydrogen production was the highest was identified as Enterobacter cloacae by the analysis of 16S rDNA sequencing and comparison. It is showed by Plackett-Burman Experimental Design that only glucose,citric buffer and reducing agent had significant effects on hydrogen production by Enterobacter cloacae FML-C1. The path of steepest ascent was undertaken to approach the optimal response region of those three factors. Central Composite Design(CCD) and Response Surface Methodology(RSM) were employed to investigate the interaction of the variables and to ascertain the optimal values of the factors,which finally led to the maximum hydrogen production(VH2) . The theoretical optimal medium conditions were:glucose 21.5 g/L,citric buffer 13.6 mL/L,reducing agent10.0 mL/L. The five tentative tests matched this model well. The final VH2 was up to 2347.4 mL/L,which was 127.42% enhanced in comparison to the original. The result shows that PB experiment design and RSM analytical method work well in selecting factors which have significant influences on the hydrogen production and,moreover,achieve the ideal optimal result.

Strains from the cellulose-containing environment were collected. Primary screening(by filter-paper Hutchison solid culture medium and sodium carboxymethylcellulose solid culture medium) and reelection(by filter-paper inorganic salt culture medium and sodium carboxymethylcellulosc Congo red coltnre medium) indicated that five strains obtained were best suited for high performance cellulose degradation. Determination of sodium carboxymethylcellulose activity(CMCA) and filter paper activity(FPA) was accomplished for each of the five. The strongest of the five in CMCA and FPA was applied to the production of cellulose bioethanol by separate hydrolysis and fermentation(SHF) and simultaneous saccharification and fermentation(SSF) respectively.

Objective To preliminarily investigate the effect of PBL applied in teaching of Obstetrics and Gynecology. Methods Ninety eight students were randomly divided into PBL pedagogy group and traditional pedagogy group in clinical practice teaching of dysfunctional uterine bleeding. Exam scores were assessed and opinion survey was summarized. Results The exam score was 80.7 ± 5.6 of PBL pedagogy group and 76.3 ± 4.9 of the other group respectively. There was significant difference between the scores of the two groups (P <0.05). Most students consider that PBL pedagogy was of benefit to students' ability. Conclusion PBL pedagogy has more advantages in training of clinical thinking than traditional teaching method.

To study and optimize the fermentation parameters for expressing human-like collagenⅡduring E. coli high-density fermentation. The effects of pH, temperature, dissolved oxygen and induction instant on the cell growth and human-like collagenⅡproduction were investigated to optimize the fermentation conditions. The results demonstrated that the following conditions were beneficial for cell growth and foreign gene expression, controlling pH in phase induction at 6.8 and initial pH at 6.5, maintaining fermentation temperature and dissolved oxygen concentration was controlled at 34?C and 20% respectively, and implementing induction at the later logarithmic growth phase. Under the optimized condition, the cell density and human-like collagenⅡyield could reach 88.4 g/L and 14.2 g/L, respectively.

Objective To investigate the feasibility of the adaptive cardio sequence prospective ECG-gated dual-source CT coronary angiography (CTCA).Methods Thirty one patients underwent prospective ECG-gated dual-source CTCA. The patients were divided into two groups: group A, heart rate ≤ 75 times / minutes, 70% of R-R interval was chose; group B, heart rate> 75 times / minutes, 40% of R-R interval was chose. Two experienced radiologists assessed the image quality of 15 segments of coronary arteries in a double blinded fashion in a four score scale. Student t test was used to compare the image quality between two groups. CT dose index(CTDIvol) and effective dose(ED) were also calculated for both groups. Results 437 segments of coronary arteries in 31 patients were included this analysis, 408 segments (93.4%) had assessable image quality, while 29 segments (6.6%) had non assessable image quality. Of 226 segments in group A, 12 segments (5.3%) had non assessable image quality; however, 17 segments (8.1%) of 211 segments in group B had non assessable image quality. The average score of image quality was 3.57±0.64 in 31 patients. There was no statistical difference for mean image quality of group A (3.65±0.39) and group B (3.41±0.43)( t=1.62,P=0.12 ) . There was a statistical difference for mean image quality for segment 10 on a per segment basis ( t = 3.8 ,P＜0.05). CTDIvol and ED were (18.88±5.04) mGy and (4.31±1.05) mSv, respectively.Conclusion Adaptive cardio sequence prospective ECG-gated dual source CT can acquire assessable image quality of coronary artery with lower radiation dose to the patients, which has the potential to be a routine CTCA technique.

Human-like collagen (HLC) was cross-linked with hyaluronic acid by genipin in different ratio. The concentrations of hyaluronic acid in the mixture were 0, 0.01%, 0.05% and 0.1%. The blood vessel tubular grafts were then fabricated by freeze-drying. Microstructure, element composite, mechanical properties, cytotoxicity grade, and biocompatibility of different vascular scaffold groups were studied by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), tensile test, burst pressure experiment, cytotoxicity experiment, endothelial cells planted in blood vessel scaffolds and hypodermic embedding of mice. The results showed that HLC-HA (0.05%) tubular scaffold exhibited interconnected well-distributed and porous structure and porosity of 94.38%; achieved the desirable mechanical property with stress of (1000.8 +/- 7.9) kPa and burst pressure of (1058.6 +/- 8.2) kPa, hypocytotoxicity, favourable cytocompatibility, hisocompatibility and disposition of degradation.
Adhesives ; chemistry ; Animals ; Biocompatible Materials ; chemistry ; Biomimetic Materials ; chemistry ; Blood Vessels ; drug effects ; physiology ; Collagen ; chemistry ; Humans ; Hyaluronic Acid ; chemistry ; Iridoid Glycosides ; Iridoids ; chemistry ; Materials Testing ; Mice ; Tissue Engineering ; instrumentation ; methods ; Tissue Scaffolds

Objective:To explore effects of different flow rates and temperature settings of high-flow nasal cannula oxygen therapy (HFNC) on patients with mild to moderate community-acquired pneumonia (CAP) accompanied by type I respiratory failure.Methods:Using the convenient sampling method, a total of 92 patients with mild to moderate CAP accompanied by type I respiratory failure who were admitted and received HFNC in the Department of Respiratory and Critical Care Medicine in a Class Ⅲ Grade A hospital in Tianjin were selected as the research objects from December 2019 to December 2020. They were randomly divided into 4 groups, including low temperature and low flow rate group (31 ℃, 30 L/min) , low temperature and high flow rate group (31℃, 50 L/min) , high temperature and low flow rate group (34℃, 30 L/min) , high temperature and high flow rate group (34 ℃, 50 L/min) , with 23 cases in every group. Two-factor factorial analysis of variance was used to compare effects of different flow rates and temperature settings of HFNC on the comfort, oxygenation index, respiratory rate and heart rate of patients with mild to moderate CAP.Results:The comfort level of patients in the low flow rate group (30 L/min) was higher than that of the high flow rate group (50 L/min) , and the comfort level of patients in the low temperature group (31 ℃) was higher than that of the high temperature group (34 ℃) . The differences were statistically significant ( P<0.01) . The oxygenation index of patients in the high flow rate group (50 L/min) was higher than that of the low flow rate group (30 L/min) , and the difference was statistically significant ( P<0.01) . Different flow rates and temperatures of HFNC have no interaction effect on the comfort, oxygenation index and heart rate of patients ( P>0.05) , but they have an interaction effects on respiratory rate ( P<0.01) . Individual effect analysis showed that the respiratory rate of patients in the low temperature and high flow rate group (31 ℃, 50 L/min) was lower than that of the high temperature and high flow rate group (34 ℃, 50 L/min) and the low temperature and low flow rate group (31 ℃, 30 L/min) , and the differences were statistically significant ( P<0.01) . Conclusions:For patients with mild to moderate CAP accompanied by type I respiratory failure, the application of HFNC should start with low temperature and low flow rate parameter settings. Under the condition of ensuring the patient's comfort, the overall effect of flow rate and temperature is integrated and the inhalation flow rate of HFNC is appropriately increased, which can increase the clinical effect of high-flow nasal cannula oxygen therapy.