1.Effect of compressive stress on viability of adipocytes
Demei ZHAO ; Qingnan MENG ; Jianguo CHEN ; Linping TANG ; Qian TAN
Chinese Journal of Medical Aesthetics and Cosmetology 2012;18(3):193-196
Objective To evaluate the viability of adipocytes after they are subjected to different compressive stress in vitro for improvement of autologous fat graft and its clinical application.Methods Fat grafts were harvested from healthy patients who underwent liposuction for body contouring.Then the fat grafts were randomly divided into 5 experimental groups,including control group without any compressive stress,and continuous compressive stress groups (0,25,50,75,and 100 kPa),and the glucose transport test was performed at days 1,2,3 and 4.An MTT assay was also performed after 4 days with continuous compressive stress in each group with the same experimental protocol for control.Routine histological examination was done in all groups to examine possible structural destruction after compressive stress.Results As compared with the control group,the glucose transport test showed transported glucose concentration decreased with an increase in compressive stress in all of the other four groups (P<0.01),and this effect would increase with action time.MTT assay showed absorbance (A492nm) also decreased with an increase in compressive stress in four days (P<0.05),the similar fndings of MTT assay on the viability of fat grafts in all five groups and correlated with the glucose transport test (r=0.838,P<0.01).Histology showed significantly distorted and fractured adipocytes and cell injury rate was to raise with an increase in compressive stress.Conclusions Our study demonstrates the harmful effect on the viability of fat grafts with an increase in compressive stress and therefore we should reduce this effect in clinical application of fat grafts.
2.Progesterone on the expression of ADAM10,Ob-R and the secretion of SLR,LEP in human chorionic tropho-blast cells
Lei GAN ; Zhen LI ; Xiaohua WU ; Demei YING ; Liping CHEN
Journal of Regional Anatomy and Operative Surgery 2015;(3):249-252
Objective To investigate the different concentrations of progesterone on the expression of a disintegrin and metalloprotease 10 (ADAM10),long form leptin receptor (Ob-R) and the secretion of soluble leptin receptor (SLR),leptin (LEP) in primary pregnancy human chorionic trophoblast cells. Methods Cultured primary human trophoblast cells and added in different concentrations of progesterone (0,100,150 and 200 ng/mL) for 24 hours. The relative expression of ADAM10 and Ob-R in the cells and the content of SLR and LEP in the supernatant were detected. Results With increasing concentrations of progesterone,early human trophoblast cells ADAM10 content gradual-ly decreased,the difference between the two groups was significant (P<0. 05). With increasing concentrations of progesterone,human chori-onic trophoblast cells in early pregnancy Ob-R expression levels increased, the difference was no statistically significant between each two groups (P>0. 05). SLR content of the cell supernatants as the concentration of progesterone increased and decreased,there are significant differences between each two groups (P>0. 05). LEP cell supernatant in each group with the increase of the concentration of progesterone concentration increased gradually between the two groups were significantly different(P>0. 05). Pearson’s test showed that the expression of expression SLR and LEP exists a significant negative correlation (R= -0. 949,P<0. 01). Conclusion Progesterone may influence the ex-pression of ADAM10,SLR and LEP by the regulation of leptin to participate GDM occurs.
3.Preparation and characterization of the chitosan-thioglycolic acid conjugates
Ganjun YUAN ; Hongqian HUANG ; Demei CHEN ; Junqing ZHANG
Chinese Journal of Marine Drugs 2000;0(06):-
Objective To prepare a new bioadhesive material-chitosan-thioglycolic acid conjugates from chitosan,and analysed the structure moreover.Methods Preparing chitosan-thioglycolic acid conjugates with a new synthesis method under catalytic reaction by NHS,and the contents of thiol groups in the conjugates were determined.Furthermore,elemental analysis and the IR spectrum of the polymer were determined.Results The content of thiol groups in the chitosan-thioglycolic acid conjugates was 1034?mol?g~(-1),and the structure was elucidated.Conclusion The new synthesis method was feasible,and the structure can be elucidated by IR spectrum.
4.In vitro activity of a new antibacterial agent levornidazole against anaerobic bacteria
Jiali HU ; Shi WU ; Demei ZHU ; Haihui HUANG ; Yuancheng CHEN ; Yang YANG ; Yingyuan ZHANG
Chinese Journal of Infection and Chemotherapy 2014;(2):100-103
Objective To determine the in vitro antibacterial activity of levornidazole against 375 anaerobic isolates.Methods Agar dilution method was used to determine the minimum inhibitory concentrations (MICs)of levornidazole,3 comparators (metronidazole,ornidazole and dextrornidazole)against 375 anaerobic isolates.Results For anaerobic gram-negative and gram-positive bacilli,and anaerobic gram-positive cocci,levornidazole displayed activity similar to or slightly higher than that of met-ronidazole,ornidazole and dextrornidazole.Levornidazole showed good activity against B.fragilis,Bacteroides thetaiotaomi-cron ,Clostridium difficile ,Clostridium perfringens ,and Peptostreptococcus magnus .The MIC90 value of levornidazole a-gainst the above-mentioned anaerobes was 0.5,1,0.25,2 and 1 mg/L,respectively.However,levornidazole and the compa-rators had poor antibacterial activity against Veillonella spp.among anaerobic gram-negative cocci.Conclusions The in vitro anti-anaerobic activity of levornidazole is similar to or slightly higher than that of metronidazole, ornidazole and dex-trornidazole.Levornidazole has good activity against both gram-negative and gram-positive anaerobic bacilli,and gram-positive anaerobic cocci,suggesting its promising clinical use.
5.Corrosive degradation of magnesium and its alloy as endovascular stent.
Shaolin CHEN ; Anlin LU ; Xiaobing HU ; Demei YU
Journal of Biomedical Engineering 2011;28(6):1246-1250
Magnesium and its alloy are used for the most potential endovascular stent material due to their excellent mechanical capabilities, adjustable corrosive properties, the little side effects of the materials and their degradation products. The in vito degradation rate of the current magnesium and its alloy as endovascular stent is very quickly so that the artery is not supported long enough to prevent negative remodeling. This review detailed the approach to enhance the corrosion resistance, in vitro corrosion rate measurement of magnesium and its alloy, as well as the in vito corrosion research when as the endovascular stents.
Alloys
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chemistry
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Biocompatible Materials
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Corrosion
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Humans
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Magnesium
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chemistry
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Materials Testing
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Stents
6.In vitro activity of tigecycline and minocycline against Van M-type vancomycin-resistantEnterococcus faecium
Chunhui CHEN ; Yan GUO ; Shi WU ; Yang YANG ; Fupin HU ; Demei ZHU ; Xiaogang XU
Chinese Journal of Infection and Chemotherapy 2016;16(3):327-329
Objective To investigate thein vitro activity of tigecycline and minocycline against VanM-type vancomycin-resistant Enterococcusfaecium.Methods A total of 45 strains of VanM-type vancomycin-resistantE. faecium were obtained from hospitals in Shanghai between 2006 and 2014. Species and vancomycin resistance genotype were identiifed by PCR and sequencing analysis. Minimal inhibitory concentrations (MICs) of ten antimicrobial agents against these strains were determined.Results All the 45 isolates were VanM-type vancomycin-resistantE. faecium, and resistant to vancomycin (MIC: 128 to >256 mg/L). And 71.1%of the strains were resistant to teicoplanin. Almost all isolates showed resistance to levolfoxacin (100%) and ampicillin (97.8%). About 15.6%, 64.4% and 82.2% of the strains were resistant to minocycline, gentamicin and rifampicin, respectively.Conclusion Tigecycline and minocycline exhibit excellentin vitro activity against these VanM-type vancomycin-resistantE. faecium isolates.
7.Research on the relation between the content of thiol group and in vitro adhesion of the chitosan-thioglycolic acid conjugates
Ganjun YUAN ; Qiuling SU ; Hongqian HUANG ; Xingliang SHEN ; Mingsheng LIU ; Demei CHEN
Chinese Journal of Marine Drugs 1994;0(01):-
Objective Research on the relation between the content of thiol group in chitosan-thioglycolic acid conjugates and in vitro adhesion. Methods Prepared chitosan-thioglycolic acid conjugates with different content of thiol group,and determined the swelling behavior,instant detachment force between test disc and mucosa,recorded the maximum detachment force(MDF),and calculated the total work of adhesion(TWA)of these samples.Results The relation between the content of thiol groups and in vitro adhesion of the chitosan-thioglycolic acid conjugates was positive correlation, the adhesion of the polymer increased along with the content of thiol group,but the rate decreased.Conclusion The adhesion of chitosan-thioglycolic acid conjugates with higher content of thiol gyoup was far more stronger than chitosan.
8.Influence of sleep deprivation on serum interleukin-1β level in rats with coronary atherosclerosis
Li TAN ; Qi HUANG ; Demei LI ; Lingling CHEN ; Yuxin ZHANG ; Zhixiao WANG
Chinese Journal of cardiovascular Rehabilitation Medicine 2014;23(1):1-5
Objective: To explore influence of sleep deprivation (SDP) on serum interleukin-1β (IL-1β) level in rats with coronary atherosclerosis (CAS). Methods: A total of 96 healthy SD rats were randomly and equally divided into normal control group, CAS group, SDP group and SDP + CAS group according to number table; rats in CAS group and SDP + CAS group were fed with high cholesterol diet to establish CAS animal model; SDP group and SDP + CAS group received SDP through small platform with water environment. Radioimmunoassay was used to measure serum concentration of IL-1β; and serum concentrations of total cholesterol (TC), triglyceride (TG), high density lipoprotein-cholesterol (HDL-C) and low density lipoprotein-cholesterol (LDL-C) were measured respectively; above indexes were compared among four groups. Results: (1) Compared with serum IL-1β level of normal control group, there were significant increase in SDP group, CAS group and SDP + CAS group[(13.33±3.20) ng/L vs. (14.40±4.41) ng/L vs. (22.21±5.94) ng/L vs. (30.17±7.45) ng/L] (P<0.05~<0.01); (2) Levels of TC, TG and LDL-C in CAS group and SDP + CAS group were significantly higher, level of HDL were significantly less than those of normal control group and SDP group (P<0.05~<0.01), levels of above indexes in SDP + CAS group were significantly higher or less than those of CAS group (P<0.05 all). Conclusion: Sleep deprivation can significantly heighten serum interleukin-1β level and total cholesterol, triglyceride, low density lipoprotein-cholesterol levels, decrease HDL level in rats with coronary atherosclerosis or sleep deprivation.
9.Diagnostic performance of ADC value and texture features based on T 2WI fat suppressed image to distinguish benign and malignant soft tissue tumors
Dong CHEN ; Bin SHI ; Mingxue ZHENG ; Fei GAO ; Jiangning DONG ; Demei SONG ; Na ZHAO ; Feng CAO ; Xinyang WEI
Chinese Journal of Radiology 2021;55(3):282-287
Objective:To investigate the value of ADC derived from DWI combined with texture analysis derived from T 2WI fat suppressed images in distinguishing benign and malignant soft tissue tumors. Methods:The MRI and DWI images of 94 patients with soft tissue tumors (44 cases with malignant and 50 cases with benign) confirmed by pathology were analyzed retrospectively in the First Affiliated Hospital of USTC West District. ADC values of solid components were measured at GE ADW4.6 workstation. The texture features were extracted by manually drawing the ROI on the maximum level of the T 2WI fat suppressed images; the ADC values and texture parameters between the two groups were statistically analyzed by SPSS17.0, and the multivariate logistic regression model were conducted to analyze and calculate the diagnostic performance. Results:ADC value of benign and malignant soft tissue tumors was (1.6±0.3)×10 -3 mm 2/s, (1.2±0.5)×10 -3 mm 2/s, respectively, and the difference was statistically significant( t=-5.382, P<0.05). Taking 1.28×10 -3 mm 2/s as the critical value, the area under curve (AUC) for the diagnosis of benign and malignant soft tissue tumors was 0.783, the sensitivity was 92.00%, and the specificity was 65.91%. Among the texture features, the AUC of frequency size, skewness, Inertia All Direction_offset7, Inverse Difference Moment angle0_offset1, Inverse Difference Moment angle0_offset7 and Haralick Correlation All Direction_offset4_SD distinguishing benign and malignant soft tissue tumors were 0.825, 0.739, 0.826, 0.816, 0.820 and 0.783, respectively. The AUC, sensitivity and specificity of the best predictive model distinguishing benign and malignant soft tissue tumors were 0.930, 88.00% and 86.36% respectively using multivariate logistic regression analysis. Conclusion:ADC combined with texture analysis is of great value in preoperative differentiation of benign and malignant soft tissue tumors.
10.Clinical pharmacokinetics and pharmacodynamics of gemifloxacin in healthy Chinese volunteers following multiple oral administration
Xiaofang LIU ; Guoying CAO ; Jicheng YU ; Yuancheng CHEN ; Jing ZHANG ; Xinyu YE ; Demei ZHU ; Yaoguo SHI ; Yingyuan ZHANG
Chinese Journal of Infectious Diseases 2012;30(9):513-519
ObjectiveTo investigate the clinical pharmacokinetics (PK) and pharmacodynamics (PD) of gemifloxacin tablet in healthy Chinese volunteers and to provide evidences for optimal clinical dosing.MethodsTwenty volunteers were enrolled in the randomized (1∶1) double-blind study,and divided into administration group and control group.Each group received multiple oral doses of 320 mg of gemifloxacin tablet or placebo.The plasma and urine samples for gemifloxacin were analyzed by igh-performance liquid chromatogram(HPLC)-fluorometricmethod. Theminimuminhibition concentrations (MIC)of gemifloxacin against190clinical isolateswere determinedby broth microdilution method.The fAUC0~24 h/MIC and fCmax/MIC,with target value of 25 and 5,were used as the indices to evaluate PK and PD characteristics of gemifloxacin. The cumulative fraction of response (CFR) of gemifloxacin against each bacterium and the probability of target attainment (PTA) under various MIC level were evaluated using Monte Carlo simulation following multiple administration at steady state.ResultsThe Cmax of gemifloxacin after once-daily oral doses for 7 days were (1.55 ±0.32) μg/mL and (1.57±0.31) μg/mL for the first and last dose,while the AUC0~24 h were (7.91±1.52) and (8.91±1.15) h · μg · mL-1,respectively.The accumulation factor was 1.13±0.05.The time-profile of gemifloxacin could be described using two-compartment model and the half-life of distribution and elimination phase were (0.64 ± 0.17) and (7.10 ± 2.10) h,respectively. The cumulative urinary excretion rates within 24 h of gemifloxacin were 34.83 % and 38.95 % for the first and the last dose,respectively.PD study showed that the MIC90 of gemifloxacin were 0.25 mg/L and 0.125 mg/L against Streptococcus pneumoniae and Moraxelle catarrhalis,respectively,while the MIC90 was 2 mg/L against Hemophilus influenza. However,most of Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA) were resistant to gemifloxacin ( MIC90 > 32mg/L).The PTA values of fAUC0~24 h/MIC and fCmax/MIC of gemifloxacin 320 mg daily for 7 days were close to 100% when MIC was ≤0.06 mg/L.ConclusionsGemifloxacin is rapidly absorbed after oral administration of single doses in healthy Chinese volunteers,and the plasma concentration could reach steady state at the third day,while a minimal accumulation is shown after consecutive 7 days dosing.The PK/PD analysis suggests that the favorable clinical and bacteriological efficacy could be obtained when using thisregimen in treatment of sensitive patients with community-acquired pneumonia and acute exacerbation of chronic obstructive pulmonary disease.