Stability analysis of unsaturated soil slope during rainfall infiltration using coupled liquid-gas-solid three-phase model

Generally, most soil slope failures are induced by rainfall infiltration, a process that involves interactions between the liquid phase, gas phase,and solid skeleton in an unsaturated soil slope. In this study, a loosely coupled liquid-gas-solid three-phase model, linking two numerical codes,TOUGH2/EOS3, which is used for water-air two-phase flow analysis, and FLAC^(3D), which is used for mechanical analysis, was established. The model was validated through a documented water drainage experiment over a sandy column and a comparison of the results with measured data and simulated results from other researchers. The proposed model was used to investigate the features of water-air two-phase flow and stress fields in an unsaturated soil slope during rainfall infiltration. The slope stability analysis was then performed based on the simulated water-air two-phase seepage and stress fields on a given slip surface. The results show that the safety factor for the given slip surface decreases first, then increases, and later decreases until the rainfall stops. Subsequently, a sudden rise occurs. After that, the safety factor decreases continually and reaches its lowest value, and then increases slowly to a steady value. The lowest value does not occur when the rainfall stops, indicating a delayed effect of the safety factor. The variations of the safety factor for the given slip surface are therefore caused by a combination of pore-air pressure, matric suction, normal stress, and net normal stress.

Effects of Sirt1 on proliferation,migration,and apoptosis of endothelial progenitor cells in peripheral blood of SD rats with chronic obstructive pulmonary disease

Objective:To explore the effect of Sirt1 on the function of endothelial progenitor cells(EPCs)in rats with chronic obstructive pulmonary disease(COPD).Methods:A rat COPD model was established via smoking and endotoxin administration for three months.The peripheral circulating EPCs were isolated by gradient centrifugation,and their functions,cell cycle distribution,apoptosis,and Sirt1 expression were examined.The function changes of EPCs in the presence or absence of Sirt1 agonist and inhibitor were estimated;meanwhile,the expressions of Sirt1,FOXO3a,NF-κB,and p53 were also evaluated.Results:The proliferation,adhesion,and migration of EPCs decreased while the apoptosis rate was increased in the COPD rats.The expression of Sirt1 protein in EPCs of the COPD group was significantly lower than that in the control group(P<0.01).The overexpression of the Sirt1 gene using a gene transfection technique or Sirt1 agonists(SRT1720)improved the proliferation,migration,and adhesion,and decreased the apoptosis of EPC.However,Sirt1 inhibitor(EX527)decreased EPC functions in the COPD group.The effect of Sirt1 expression on EPC function may be related to reduction of FOXO3a and increase of NF-κB and p53 activity.Conclusions:Increased expression of Sirt1 can improve the proliferation and migration of EPCs and reduce their apoptosis in COPD rats.This change may be related to FOXO3a,NF-κB,and p53 signaling pathways.

Research progress of transfering mitochondria application in nanotubes in treatment of acute lung injury sepsis

Acute lung injury (ALI) is a common complication of sepsis with characteristics of acute onset, rapid change in the disease and high mortality. Since current clinical treatment can only alleviate the unfavorable condition to a certain extent but cure, we urgently need to find an effective treatment. Most scholars believe that sepsis-induced ALI is associated with extensive mitochondrial damage. In recent years, a widely studied pluripotent stem cell that is mesenchymal stem cell has been proved to alleviate and treat sepsis-induced ALI by transporting mitochondria via nanotubes in a microtubule-dependent manner. Research progress in this field will be reviewed in this study.

Midkine ameliorates LPS-induced apoptosis of airway smooth muscle cells via the Notch2 pathway

Objective:To evaluate the effect of midkine on lipopolysaccharide(LPS)-induced airway smooth muscle cells(ASMCs).Methods:LPS-stimulated acute lung injury model was used to analyze the effect of midkine on ASMCs in vitro.Recombinant midkine and midkine siRNA were used to investigate the role of Notch2 signaling pathway.Cell proliferation was assessed using Cell Counting Kit-8 assay.Additionally,apoptosis was measured by flow cytometry and protein and mRNA expression of midkine and Notch2 was assessed by Western blotting and qPCR,respectively.Immunofluorescence analysis was also conducted.Results:LPS increased the mRNA and protein expression of midkine and Notch2.Midkine silencing reduced LPS-induced midkine and Notch2 expression.In addition,midkine silencing further reduced the viability and increased apoptosis of ASMCs induced by LPS,which was attenuated by recombinant midkine.Conclusions:The midkine/Notch2 signaling pathway plays a regulatory role in ASMC proliferation and apoptosis in airway inflammation.

Analysis of the disease spectra in patients seeking emergency medical treatment in Haikou, China

Objective: To explore the characteristics of medical emergency disease spectra in Emergency Department of Haikou, China;and to provide clinical data for emergent disease treatment as well as emergency department personnel and equipment management. Methods: A total of 11870 patients (over 16 years old) who visited Emergency Departments of the First Affiliated Hospital of Hainan Medical University, Haikou city from January 1, 2015, through December 31, 2015 were selected. Data on patients' age, sex, diagnosis, treatment duration, and treatment month were analyzed with Microsoft Excel. Results: Peak treatment times were from 18:00 to 24:00. The top four diseases were involved with respiratory, digestive, nervous, and cardiovascular systems, respectively. Respiratory problems peaked from November to February and digestive problems peaked from February to August. Temperatures ranging from >22.5 ℃to 26 ℃ and high humidity exacerbated respiratory and digestive system diseases. Conclusion:The frequency of specific diseases that require emergency room care are affected by the local climate of Hainan Province.

Selection of quality markers of Jasminum amplexicaule based on its anti-diarrheal and anti-inflammatory activities: Effect-target affiliation-traceability-pharmacokinetics strategy

Objective:To investigate therapeutic mechanism in Jasminum amplexicaule(Oleaceae)and verify its main active component as quality control markers Methods:Established mouse models of diarrhea,intestinal angina,and inflammation were firstly used to select herb fractions with optimum efficacy,followed by an in vitro experiment to determine key targets associated with effects of J.amplexicaule extract.The selected fractions were isolated and purified,its components were identified,and the obtained compounds were verified for their effects on NF-κB and i NOS.Finally,effective compounds were administered to rats,their plasma pharmacokinetic parameters were calculated,and quality markers(QMs)reflecting therapeutic activities of J.amplexicaule were confirmed.Results:Trichloromethane and ethyl acetate fractions had significant anti-diarrheal,anti-inflammatory,and analgesic effects.The trichloromethane fraction also reduced BDNF,p38 MAPK,p-p38 MAPK,NF-κB p65,and p-NF-κB p65 levels in the ileum in a rhubarb-induced diarrhea mouse model.Additionally,it inhibited LPS-induced NF-κB transcription and nitric oxide(NO)production in RAW264.7 macrophages,which suppressed i NOS expression.Therefore,the trichloromethane fraction was further investigated.QMs candidate selection identified 17 compounds,and results of in-vitro therapeutic validation indicated that methyl caffeate and isochlorogenic acid B had the strongest anti-diarrheal,anti-inflammatory,and analgesic activities.After being validated by a UHPLC–MS-MS method,concentrations of these target compounds were accurately determined in the rat plasma and pharmacokinetic parameters were calculated.Cmax,tmax,and t1/2 were respectively 575.35 ng/mL(2.963 nmol/mL),0.5 h,and 0.45 h for methyl caffeate and 262.03 ng/m L(0.5034 nmol/mL),0.25 h,and 2.03 h for isochlorogenic acid B.Because these candidate compounds exhibited favorable pharmacokinetics,they were considered as QMs of J.amplexicaule.Conclusions:The present study accurately and effectively identified QMs of J.amplexicaule that act as indicators of efficacy and quality.

Magnetic Resonance Three-dimensional Cube Technique in the Measurement of Piglet Femoral Anteversion

Background： The accurate measurement of the femoral anteversion （FA） angle is always a topic of much debate in the orthopedic surgery and radiology research. We aimed to explore a new FA measurement method to acquire accurate results without radiation damage using piglet model. Methods： A total of thirty piglets were assigned to two groups based on the age. Bilateral femora were imaged with 3.0-T magnetic resonance （MR） and 64-slice computed tomography （CT） examinations on all piglets. FA was measured on MR-three-dimensional （3D） postprocessing software with a four-step method： initial validation of the femoral condylar axis, validation of the condylar plane, validation of the femoral neck axis, and line-plane angle measurement of FA. After MR and CT examinations, all piglets were sacrificed and their degree of FA was measured using their excised, dried femora. MR, CT, and dried-femur measurement results were analyzed statistically; M R and CT measurements were compared for accuracy against each other and against the gold standard dried femur measurement. Results： In both groups, the mean FA value measured by MR was lower than that measured by CT. A statistically significant difference was observed between CT- and dried-femur measurements but not between MR- and dried-femur measurements. A higher correlation （0.783 vs. 0.408） and a higher consistency （0.863 vs. 0.578） with dried-femur measurement results were seen for MR measurements than CT measurements in the 1 -week age group. However, in the 8-week age group, similar correlations （0.707 vs. 0.669） and consistencies （0.864 vs. 0.82 l ） were observed. Conclusions： Noninvasive MR-3D-Cube reconstruction was able to accurately measure FA in piglets. Particularly in the 1-week age group with a larger proportion of cartilaginous structures, the correlation and consistency between MR- and dried-femur measurement results were higher than those between CT- and dried-femur measurements, suggesting that MR may be a new useful examination tool for FA-related diseases in children.