In a multi-bubble system, the bubble behavior is modulated by the primary acoustic field and the secondary acoustic field. To explore the translational motion of bubbles in cavitation liquids containing high-concentra...In a multi-bubble system, the bubble behavior is modulated by the primary acoustic field and the secondary acoustic field. To explore the translational motion of bubbles in cavitation liquids containing high-concentration cavitation nuclei,evolutions of bubbles are recorded by a high-speed camera, and translational trajectories of several representative bubbles are traced. It is found that translational motion of bubbles is always accompanied by the fragmentation and coalescence of bubbles, and for bubbles smaller than 10 μm, the possibility of bubble coalescence is enhanced when the spacing of bubbles is less than 30 μm. The measured signals and their spectra show the presence of strong negative pressure, broadband noise,and various harmonics, which implies that multiple interactions of bubbles appear in the region of high-intensity cavitation.Due to the strong coupling effect, the interaction between bubbles is random. A simplified triple-bubble model is developed to explore the interaction patterns of bubbles affected by the surrounding bubbles. Patterns of bubble interaction, such as attraction, repulsion, stable spacing, and rebound of bubbles, can be predicted by the theoretical analysis, and the obtained results are in good agreement with experimental observations. Mass exchange between the liquid and bubbles as well as absorption in the cavitation nuclei also plays an important role in multi-bubble cavitation, which may account for the weakening of the radial oscillations of bubbles.展开更多
Multilevel phase-change memory is an attractive technology to increase storage capacity and density owing to its high-speed,scalable and non-volatile characteristics.However,the contradiction between thermal stability...Multilevel phase-change memory is an attractive technology to increase storage capacity and density owing to its high-speed,scalable and non-volatile characteristics.However,the contradiction between thermal stability and operation speed is one of key factors to restrain the development of phase-change memory.Here,N-doped Ge_(2)Sb_(2)Te_(5)-based optoelectronic hybrid memory is proposed to simultaneously implement high thermal stability and ultrafast operation speed.The picosecond laser is adopted to write/erase information based on reversible phase transition characteristics whereas the resistance is detected to perform information readout.Results show that when N content is 27.4 at.%,N-doped Ge_(2)Sb_(2)Te_(5)film possesses high ten-year data retention temperature of 175℃and low resistance drift coefficient of 0.00024 at 85℃,0.00170 at 120℃,and 0.00249 at 150℃,respectively,owing to the formation of Ge–N,Sb–N,and Te–N bonds.The SET/RESET operation speeds of the film reach 520 ps/13 ps.In parallel,the reversible switching cycle of the corresponding device is realized with the resistance ratio of three orders of magnitude.Four-level reversible resistance states induced by various crystallization degrees are also obtained together with low resistance drift coefficients.Therefore,the N-doped Ge_(2)Sb_(2)Te_(5)thin film is a promising phase-change material for ultrafast multilevel optoelectronic hybrid storage.展开更多
According to classical nucleation theory, gas nuclei can generate and grow into a cavitation bubble when the liquid pressure exceeds a threshold. However, classical nucleation theory does not include boundary effects....According to classical nucleation theory, gas nuclei can generate and grow into a cavitation bubble when the liquid pressure exceeds a threshold. However, classical nucleation theory does not include boundary effects. An enclosed spherical liquid cavity surrounded by elastic medium is introduced to model the nucleation process in tissue. Based on the equilibrium pressure relationship of a quasi-static process, the expressions of the threshold and the modified nucleation rate are derived by considering the tissue elasticity. It is shown that the constraint plays an important role in the nucleation process. There is a positive correlation between nucleation threshold pressure and constraint, which can be enhanced by an increasing tissue elasticity and reducing the size of the cavity. Meanwhile, temperature is found to be a key parameter of nucleation process, and cavitation is more likely to occur in confined liquids at temperature T > 100℃. In contrast, less influences are induced by these factors, such as bulk modulus, liquid cavity size, and acoustic frequency. Although these theoretical predictions of the thresholds have been demonstrated by many previous researches, much lower thresholds can be obtained in liquids containing dissolved gases, e.g., the nucleation threshold is about-21 MPa in a liquid of 0.8-nm gas nuclei at room temperature. Moreover, when there is a gas nucleus of 20 nm, the theoretical threshold pressure might be less than1 MPa.展开更多
As a vital and integral component of transportation infrastructure,pavement has a direct and tangible impact on socio-economic sustainability.In recent years,an influx of groundbreaking and state-of-the-art materials,...As a vital and integral component of transportation infrastructure,pavement has a direct and tangible impact on socio-economic sustainability.In recent years,an influx of groundbreaking and state-of-the-art materials,structures,equipment,and detection technologies related to road engineering have continually and progressively emerged,reshaping the landscape of pavement systems.There is a pressing and growing need for a timely summarization of the current research status and a clear identification of future research directions in these advanced and evolving technologies.Therefore,Journal of Road Engineering has undertaken the significant initiative of introducing a comprehensive review paper with the overarching theme of“advanced road materials,structures,equipment,and detection technologies”.This extensive and insightful review meticulously gathers and synthesizes research findings from 39 distinguished scholars,all of whom are affiliated with 19 renowned universities or research institutions specializing in the diverse and multidimensional field of highway engineering.It covers the current state and anticipates future development directions in the four major and interconnected domains of road engineering:advanced road materials,advanced road structures and performance evaluation,advanced road construction equipment and technology,and advanced road detection and assessment technologies.展开更多
Microbial enhanced oil recovery (MEOR) is the research focus in the field of energy development as an environmentally friendly and low cost technology. MEOR can bes divided into indigenous microbial oil recovery and e...Microbial enhanced oil recovery (MEOR) is the research focus in the field of energy development as an environmentally friendly and low cost technology. MEOR can bes divided into indigenous microbial oil recovery and exogenous microbial oil recovery. The ultimate goal of indigenous microbial flooding is to enhance oil recovery via stimulation of specific indigenous microorganisms by injecting optimal nutrients. For studying the specific rule to activate the indigenous community during the long-term injection period, a series of indigenous displacement flooding experiments were carried out by using the long-core physical simulation test. The experimental results have shown that the movement of nutrients components (i.e., carbon/nitrogen/phosphorus) differed from the consumption of them. Moreover, there was a positive relationship between the nutrients concentration and bacteria concentration once observed in the produced fluid. And the trend of concentration of acetic acid was consistent with that of methanogens. When adding same activators, the impacts of selective activators to stimulate the indigenous microorganisms became worse along with the injection period, which led to less oil recovery efficiency.展开更多
目的研究miR-144-3p靶向调控ATP结合转运蛋白G家族成员2(ATP-binding transporter G family member 2,ABCG2)对胃癌(gastriccancer,GC)HGC-27细胞侵袭和迁移能力的影响,并对其作用机制进行初步探讨.方法通过qRT-PCR检测人GCHGC-27细胞...目的研究miR-144-3p靶向调控ATP结合转运蛋白G家族成员2(ATP-binding transporter G family member 2,ABCG2)对胃癌(gastriccancer,GC)HGC-27细胞侵袭和迁移能力的影响,并对其作用机制进行初步探讨.方法通过qRT-PCR检测人GCHGC-27细胞株和人胃黏膜上皮GES-1细胞株中miR-144-3p和ABCG2的表达情况;通过靶基因预测软件预测miR-144-3p和ABCG2靶向结合位点,通过双荧光素酶报告基因实验检测二者靶向结合关系;通过qRT-PCR检测miR-144-3p mimic或miR-144-3p inhibitor转染GC细胞后miR-144-3p及ABCG2的表达水平;通过明胶酶谱实验检测对转染ABCG2 siRNA的GC细胞中基质金属蛋白酶-2(matrix metalloproteinase-2, MMP-2)和基质金属蛋白酶-9(matrix metalloproteinase-9, MMP-9)活性的影响;通过Transwell侵袭和迁移实验检测转染miR-144-3p mimic、miR-144-3p inhibitor、ABCG2 siRNA对GC细胞侵袭和迁移能力的影响.结果与正常细胞组人胃黏膜上皮GES-1细胞株相比, GC细胞组人GCHGC-27细胞株中miR-144-3p的表达量明显降低, ABCG2的表达水平明显升高,差异具有统计学意义(P<0.05);靶基因预测miR-144-3p和ABCG2 3’UTR存在结合位点,双荧光素酶报告基因实验证实了miR-144-3p和ABCG2靶向结合关系;与对照组相比,转染miR-144-3p mimic组GC细胞中miR-144-3p的表达明显升高, ABCG2的表达明显降低,细胞侵袭和迁移能力显著降低,差异具有统计学意义(P<0.05),转染miR-144-3p inhibitor则表现出相反的作用;明胶酶谱实验检测结果表明ABCG2 siRNA转染可显著抑制GC细胞中MMP-2和MMP-9蛋白活性,抑制GC细胞侵袭和迁移能力,差异具有统计学意义(P<0.05).结论 MiR-144-3p能够抑制GC细胞侵袭和迁移能力,其作用机制与靶向调控ABCG2-MMP-2/9信号通路有关.展开更多
Aim Understanding the response of mesenchymal stem cells （MSCs） to mechanical strain and their consequent gene expression patterns will broaden our knowledge of the mechanobiology of distraction osteogenesis. Method...Aim Understanding the response of mesenchymal stem cells （MSCs） to mechanical strain and their consequent gene expression patterns will broaden our knowledge of the mechanobiology of distraction osteogenesis. Methodology In this study, a single period of cyclic mechanical stretch （0.5 Hz, 2,000 με） was performed on rat bone marrow MSCs. Cellular proliferation and alkaline phosphatase （ALP） activity was examined. The mRNA expression of six bone-related genes （Ets-1, bFGF, IGF-Ⅱ, TGF-β, Cbfal and ALP） was detected using real-time quantitative RT-PCR. Results The results showed that mechanical strain can promote MSCs proliferation, increase ALP activity, and up-regulate the expression of these genes. A significant increase in Ets-1 expression was detected immediately after mechanical stimulation, but Cbfal expression became elevated later. The temporal expression pattem of ALP coincided perfectly with Cbfal. Conclusion The results of this study suggest that mechanical strain may act as a stimulator to induce differentiation of MSCs into osteoblasts, and that these bone-related genes may play different roles in the response of MSCs to mechanical stimulation.展开更多
AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice. METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A contr...AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice. METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A control group received the vehicle by gavage. Rebamipide (100 mg/kg, 200 mg/kg, 400 mg/kg) was administered intragastrically once a day for 3 d 4 h after diclofenac administration. Intestinal permeability was evaluated by Evans blue and the FITC-dextran method. The ultrastructure of the mucosal barrier was evaluated by transmission electron microscopy (TEM). Mitochondrial function including mitochondrial swelling, mitochondrial membrane potential, mitochondrial nicotinamide adenine dinucleotide-reduced (NADH) levels, succinate dehydrogenase (SDH) and ATPase activities were measured. Small intestinal mucosa was collected for assessment of malondialdehyde (MDA) content and myeloperoxidase (MPO) activity. RESULTS: Compared with the control group, intestinal permeability was significantly increased in the diclofenac group, which was accompanied by broken tight junctions, and significant increases in MDA content and MPO activity. Rebamipide significantly reduced intestinal permeability, improved inter-cellular tight junctions, and was associated with decreases in intestinal MDA content and MPO activity. At the mitochondrial level, rebamipide increased SDH and ATPase activities, NADH level and decreased mitochondrial swelling. CONCLUSION: Increased intestinal permeability induced by diclofenac can be attenuated by rebamipide, which partially contributed to the protection of mitochondrial function.展开更多
BACKGROUND Inflammatory bowel disease(IBD)is characterized by chronic and non-specific inflammation of the intestinal mucosa and mainly includes ulcerative colitis and Crohn's disease.AIM To explore the beneficial...BACKGROUND Inflammatory bowel disease(IBD)is characterized by chronic and non-specific inflammation of the intestinal mucosa and mainly includes ulcerative colitis and Crohn's disease.AIM To explore the beneficial effect of ToxoROP16I/III-induced M2 phynotype macrophages in homeostasis of IBDs through downregulation of M1 inflammatory cells.METHODS RAW264.7 macrophages stimulated by lipopolysaccharide(LPS)(M1 cells)were co-cultured with Caco-2 cells as an inflammatory model of IBD in vitro.The expression of ToxoROP16I/III was observed in RAW264.7 macrophages that were transfected with pEGFP-rop16I/III.The phenotypes of M2 and M1 macrophage cells were assessed by quantitative real-time reverse transcriptase polymerase chain reaction and the expression of tumor necrosis factor(TNF)-α,interleukin(IL)-1β,IL-6,transforming growth factor(TGF)-β1,IL-10,inducible nitric oxide synthase(iNOS),and arginase-1(Arg-1)was detected.The expression of iNOS,Arg-1,signal transducer and activator of transcription 3(Stat3),p-Stat3,Stat6,p-Stat6,programmed death ligand-2(PD-L2),caspase-3,-8,and-9 was analyzed by Western blotting,and Griess assays were performed to detect nitric oxide(NO).TNF-α,IL-1β,IL-6,TGF-β1,and IL-10 expression in the supernatants was detected by enzyme-linked immunosorbent assay,and Caco-2 cell apoptosis was co-culture system.RESULTS M1 cells exhibited significantly increased production of iNOS,NO,TNF-α,IL-1β,and IL-6,while ToxoROP16I/III induced macrophage bias to M2 cells in vitro,showing increased expression of Arg-1,IL-10 and TGF-β1 and elevated production of p-Stat3 and p-Stat6.The mixed M1 and M2 cell culture induced by ToxoROP16I/III exhibited decreased production of NO and iNOS and upregulated expression of Arg-1 and PD-L2.Accordingly,Caco-2 cells became apoptotic,and apoptosis-associated proteins such as caspase-3,-8 and-9 were dampened during co-culture of M1 and M2 cells.Flow cytometry analysis showed that co-culture of M1 cells with Caco-2 cells facilitated the apoptosis of Caco-2 cells,but co-culture of M1 and M2 cells alleviated Caco-2 cell apoptosis.CONCLUSION ToxoROP16I/III-induced M2 macrophages inhibited apoptosis of Caco-2 cells caused by M1 macrophages.This finding may help gain a better understanding of the underlying mechanism and represent a promising therapeutic strategy for IBDs.展开更多
BACKGROUND The complications acute lung injury and acute kidney injury caused by severe inflammation are the main reasons of high mortality of severe acute pancreatitis(SAP).These two complications can both lead to wa...BACKGROUND The complications acute lung injury and acute kidney injury caused by severe inflammation are the main reasons of high mortality of severe acute pancreatitis(SAP).These two complications can both lead to water metabolism and acid-base balance disorders,which could act as additional critical factors affecting the disease trend.Aquaporins(AQPs),which can regulate the transmembrane water transport,have been proved to participate in the pathophysiological process of SAP and the associated complications,such as acute lung injury and acute kidney injury.Thus,exploring herbs that can effectively regulate the expression of AQP in SAP could benefit the prognosis of this disease.AIM To determine whether Yue-Bi-Tang(YBT)can regulate the water metabolism in rats with severe acute pancreatitis via regulating the expression of aquaporins.METHODS Sprague-Dawley rats were randomly divided into three groups,sham operation group(SOG),model group(MG),and treatment group(TG).SAP was induced with 3.5%sodium taurocholate in the MG and TG.Rats in the TG were administered with YBT while SOG and MG rats were given the same volume of saline.Blood and tissue samples were harvested to detect serum inflammatory cytokines,histopathological changes,malondialdehyde and superoxide dismutase in the lung,and protein and mRNA expression of kidney injury molecule-1,α-smooth muscle actin,and vimentin in the kidney,and AQP1 and 4 in the lung,pancreas,and kidney.RESULTS The serum interleukin-10,tumor necrosis factorα,and creatinine levels were higher in the MG than in the SOG.Tumor necrosis factorαlevel in the TG was lower than that in the MG.Malondialdehyde level in lung tissues was higher than in the SOG.The pathological scores and edema scores of the pancreas,lung,and kidney tissues in the MG were all higher than those in the SOG and TG.The protein expression of AQP4 in lung tissues and AQP1 in kidney tissues in the MG were higher than those in the SOG and TG.The expression of vimentin was significantly higher in the MG than in the SOG.The expression of AQP1 mRNA in the lung and kidney,and AQP4 mRNA in the kidney was up-regulated in the MG compared to the SOG.CONCLUSION YBT might regulate water metabolism to reduce lung and kidney edema of SAP rats via decreasing AQP expression,and alleviate the tissue inflammatory injury.展开更多
Objective The effect of dietary restriction, intense exercise and menstrual dysfunction on bone mineral density remains controversial. The aim of this study was to assess the skeletal health status and relationship be...Objective The effect of dietary restriction, intense exercise and menstrual dysfunction on bone mineral density remains controversial. The aim of this study was to assess the skeletal health status and relationship between bone mineral density and nutrient intake, menstrual status, estrogen level and other factos in Chinese adolescent dancers. Methods Sixty dancers and 77 healthy controls underwent measurements of bone density, body composition, and estrogen level. Nutrient intake, menstrual status and physical activity were assessed with questionnaires. The correlation between these factors were analyzed. Results The dancers under study had a significantly lean body mass index （18.3±1.4 kg/m^2 vs. 21.7±3.1 kg/m^2）, lower percentage of body fat （0.25±0.05 vs. 0.34±0.04） and later age at menarche （14.0±0.9 y vs. 13.0±1.3 y）, and the estrogen level, daily calorie and fat intake in them were also lower than in the controls. All the dancers undertook intensive physical activity every day and up to 69% of them suffered from irregular menarche. Yet they had relatively high BMD and BMC of the total body and legs than the controls after adjusting for BM1 and age. Site-specific BMD was positively correlated to BMI, body composition and training hours per week and negatively correlated to the age at menarche and menstrual frequency. Conclusions The relatively high BMD and BMC of the dancers at the total body and legs were probably caused by high levels of weight-bearing physical activity. To ameliorate disordered eating, especially low energy intake might be helpful to prevent the Triad and to improve the bone health in adolescent dancers.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11974232 and 12374441)the Fund from the Yulin Science and Technology Bureau,China(Grant No.CXY-2022-178).
文摘In a multi-bubble system, the bubble behavior is modulated by the primary acoustic field and the secondary acoustic field. To explore the translational motion of bubbles in cavitation liquids containing high-concentration cavitation nuclei,evolutions of bubbles are recorded by a high-speed camera, and translational trajectories of several representative bubbles are traced. It is found that translational motion of bubbles is always accompanied by the fragmentation and coalescence of bubbles, and for bubbles smaller than 10 μm, the possibility of bubble coalescence is enhanced when the spacing of bubbles is less than 30 μm. The measured signals and their spectra show the presence of strong negative pressure, broadband noise,and various harmonics, which implies that multiple interactions of bubbles appear in the region of high-intensity cavitation.Due to the strong coupling effect, the interaction between bubbles is random. A simplified triple-bubble model is developed to explore the interaction patterns of bubbles affected by the surrounding bubbles. Patterns of bubble interaction, such as attraction, repulsion, stable spacing, and rebound of bubbles, can be predicted by the theoretical analysis, and the obtained results are in good agreement with experimental observations. Mass exchange between the liquid and bubbles as well as absorption in the cavitation nuclei also plays an important role in multi-bubble cavitation, which may account for the weakening of the radial oscillations of bubbles.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.62205231 and 22002102)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(Grant No.KYCX223271)Jiangsu Key Laboratory for Environment Functional Materials。
文摘Multilevel phase-change memory is an attractive technology to increase storage capacity and density owing to its high-speed,scalable and non-volatile characteristics.However,the contradiction between thermal stability and operation speed is one of key factors to restrain the development of phase-change memory.Here,N-doped Ge_(2)Sb_(2)Te_(5)-based optoelectronic hybrid memory is proposed to simultaneously implement high thermal stability and ultrafast operation speed.The picosecond laser is adopted to write/erase information based on reversible phase transition characteristics whereas the resistance is detected to perform information readout.Results show that when N content is 27.4 at.%,N-doped Ge_(2)Sb_(2)Te_(5)film possesses high ten-year data retention temperature of 175℃and low resistance drift coefficient of 0.00024 at 85℃,0.00170 at 120℃,and 0.00249 at 150℃,respectively,owing to the formation of Ge–N,Sb–N,and Te–N bonds.The SET/RESET operation speeds of the film reach 520 ps/13 ps.In parallel,the reversible switching cycle of the corresponding device is realized with the resistance ratio of three orders of magnitude.Four-level reversible resistance states induced by various crystallization degrees are also obtained together with low resistance drift coefficients.Therefore,the N-doped Ge_(2)Sb_(2)Te_(5)thin film is a promising phase-change material for ultrafast multilevel optoelectronic hybrid storage.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11974232 and 11727813)。
文摘According to classical nucleation theory, gas nuclei can generate and grow into a cavitation bubble when the liquid pressure exceeds a threshold. However, classical nucleation theory does not include boundary effects. An enclosed spherical liquid cavity surrounded by elastic medium is introduced to model the nucleation process in tissue. Based on the equilibrium pressure relationship of a quasi-static process, the expressions of the threshold and the modified nucleation rate are derived by considering the tissue elasticity. It is shown that the constraint plays an important role in the nucleation process. There is a positive correlation between nucleation threshold pressure and constraint, which can be enhanced by an increasing tissue elasticity and reducing the size of the cavity. Meanwhile, temperature is found to be a key parameter of nucleation process, and cavitation is more likely to occur in confined liquids at temperature T > 100℃. In contrast, less influences are induced by these factors, such as bulk modulus, liquid cavity size, and acoustic frequency. Although these theoretical predictions of the thresholds have been demonstrated by many previous researches, much lower thresholds can be obtained in liquids containing dissolved gases, e.g., the nucleation threshold is about-21 MPa in a liquid of 0.8-nm gas nuclei at room temperature. Moreover, when there is a gas nucleus of 20 nm, the theoretical threshold pressure might be less than1 MPa.
基金support from the European Union's Horizon 2020 Research and Innovation Program under the Marie Skłodowska-Curie grant agreement No.101024139,the RILEM technical committee TC 279 WMR(valorisation of waste and secondary materials for roads),RILEM technical committee TC-264 RAP(asphalt pavement recycling)the Swiss National Science Foundation(SNF)grant 205121_178991/1 for the project titled“Urban Mining for Low Noise Urban Roads and Optimized Design of Street Canyons”,National Natural Science Foundation of China(No.51808462,51978547,52005048,52108394,52178414,52208420,52278448,52308447,52378429)+9 种基金China Postdoctoral Science Foundation(No.2023M730356)National Key R&D Program of China(No.2021YFB2601302)Natural Science Basic Research Program of Shaanxi(Program No.2023-JC-QN-0472)Postdoctoral Science Foundation of Anhui Province(2022B627)Shaanxi Provincial Science and Technology Department(No.2022 PT30)Key Technological Special Project of Xinxiang City(No.22ZD013)Key Laboratory of Intelligent Manufacturing of Construction Machinery(No.IMCM2021KF02)the Applied Basic Research Project of Sichuan Science and Technology Department(Free Exploration Type)(Grant No.2020YJ0039)Key R&D Support Plan of Chengdu Science and Technology Project-Technology Innovation R&D Project(Grant No.2019-YF05-00002-SN)the China Postdoctoral Science Foundation(Grant No.2018M643520).
文摘As a vital and integral component of transportation infrastructure,pavement has a direct and tangible impact on socio-economic sustainability.In recent years,an influx of groundbreaking and state-of-the-art materials,structures,equipment,and detection technologies related to road engineering have continually and progressively emerged,reshaping the landscape of pavement systems.There is a pressing and growing need for a timely summarization of the current research status and a clear identification of future research directions in these advanced and evolving technologies.Therefore,Journal of Road Engineering has undertaken the significant initiative of introducing a comprehensive review paper with the overarching theme of“advanced road materials,structures,equipment,and detection technologies”.This extensive and insightful review meticulously gathers and synthesizes research findings from 39 distinguished scholars,all of whom are affiliated with 19 renowned universities or research institutions specializing in the diverse and multidimensional field of highway engineering.It covers the current state and anticipates future development directions in the four major and interconnected domains of road engineering:advanced road materials,advanced road structures and performance evaluation,advanced road construction equipment and technology,and advanced road detection and assessment technologies.
文摘Microbial enhanced oil recovery (MEOR) is the research focus in the field of energy development as an environmentally friendly and low cost technology. MEOR can bes divided into indigenous microbial oil recovery and exogenous microbial oil recovery. The ultimate goal of indigenous microbial flooding is to enhance oil recovery via stimulation of specific indigenous microorganisms by injecting optimal nutrients. For studying the specific rule to activate the indigenous community during the long-term injection period, a series of indigenous displacement flooding experiments were carried out by using the long-core physical simulation test. The experimental results have shown that the movement of nutrients components (i.e., carbon/nitrogen/phosphorus) differed from the consumption of them. Moreover, there was a positive relationship between the nutrients concentration and bacteria concentration once observed in the produced fluid. And the trend of concentration of acetic acid was consistent with that of methanogens. When adding same activators, the impacts of selective activators to stimulate the indigenous microorganisms became worse along with the injection period, which led to less oil recovery efficiency.
基金supported by grants from the National Nature Science Foundation of China (No. 30772454)Science and Technology Bureau of Sichuan Province (No. 2006z09-013)
文摘Aim Understanding the response of mesenchymal stem cells （MSCs） to mechanical strain and their consequent gene expression patterns will broaden our knowledge of the mechanobiology of distraction osteogenesis. Methodology In this study, a single period of cyclic mechanical stretch （0.5 Hz, 2,000 με） was performed on rat bone marrow MSCs. Cellular proliferation and alkaline phosphatase （ALP） activity was examined. The mRNA expression of six bone-related genes （Ets-1, bFGF, IGF-Ⅱ, TGF-β, Cbfal and ALP） was detected using real-time quantitative RT-PCR. Results The results showed that mechanical strain can promote MSCs proliferation, increase ALP activity, and up-regulate the expression of these genes. A significant increase in Ets-1 expression was detected immediately after mechanical stimulation, but Cbfal expression became elevated later. The temporal expression pattem of ALP coincided perfectly with Cbfal. Conclusion The results of this study suggest that mechanical strain may act as a stimulator to induce differentiation of MSCs into osteoblasts, and that these bone-related genes may play different roles in the response of MSCs to mechanical stimulation.
文摘AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice. METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A control group received the vehicle by gavage. Rebamipide (100 mg/kg, 200 mg/kg, 400 mg/kg) was administered intragastrically once a day for 3 d 4 h after diclofenac administration. Intestinal permeability was evaluated by Evans blue and the FITC-dextran method. The ultrastructure of the mucosal barrier was evaluated by transmission electron microscopy (TEM). Mitochondrial function including mitochondrial swelling, mitochondrial membrane potential, mitochondrial nicotinamide adenine dinucleotide-reduced (NADH) levels, succinate dehydrogenase (SDH) and ATPase activities were measured. Small intestinal mucosa was collected for assessment of malondialdehyde (MDA) content and myeloperoxidase (MPO) activity. RESULTS: Compared with the control group, intestinal permeability was significantly increased in the diclofenac group, which was accompanied by broken tight junctions, and significant increases in MDA content and MPO activity. Rebamipide significantly reduced intestinal permeability, improved inter-cellular tight junctions, and was associated with decreases in intestinal MDA content and MPO activity. At the mitochondrial level, rebamipide increased SDH and ATPase activities, NADH level and decreased mitochondrial swelling. CONCLUSION: Increased intestinal permeability induced by diclofenac can be attenuated by rebamipide, which partially contributed to the protection of mitochondrial function.
基金Supported by the National Natural Science Foundation of China,No.81471983the Key Research and Development Plan Project of Anhui Province,Department of Science and Technology 2019,No.201904a07020043+1 种基金the Key Project of Natural Science Research in the Universities of Anhui Provence,No.KJ2017A202the Research Fund Project of Anhui Institute of Transforming Medicine,No.2017zhyx04
文摘BACKGROUND Inflammatory bowel disease(IBD)is characterized by chronic and non-specific inflammation of the intestinal mucosa and mainly includes ulcerative colitis and Crohn's disease.AIM To explore the beneficial effect of ToxoROP16I/III-induced M2 phynotype macrophages in homeostasis of IBDs through downregulation of M1 inflammatory cells.METHODS RAW264.7 macrophages stimulated by lipopolysaccharide(LPS)(M1 cells)were co-cultured with Caco-2 cells as an inflammatory model of IBD in vitro.The expression of ToxoROP16I/III was observed in RAW264.7 macrophages that were transfected with pEGFP-rop16I/III.The phenotypes of M2 and M1 macrophage cells were assessed by quantitative real-time reverse transcriptase polymerase chain reaction and the expression of tumor necrosis factor(TNF)-α,interleukin(IL)-1β,IL-6,transforming growth factor(TGF)-β1,IL-10,inducible nitric oxide synthase(iNOS),and arginase-1(Arg-1)was detected.The expression of iNOS,Arg-1,signal transducer and activator of transcription 3(Stat3),p-Stat3,Stat6,p-Stat6,programmed death ligand-2(PD-L2),caspase-3,-8,and-9 was analyzed by Western blotting,and Griess assays were performed to detect nitric oxide(NO).TNF-α,IL-1β,IL-6,TGF-β1,and IL-10 expression in the supernatants was detected by enzyme-linked immunosorbent assay,and Caco-2 cell apoptosis was co-culture system.RESULTS M1 cells exhibited significantly increased production of iNOS,NO,TNF-α,IL-1β,and IL-6,while ToxoROP16I/III induced macrophage bias to M2 cells in vitro,showing increased expression of Arg-1,IL-10 and TGF-β1 and elevated production of p-Stat3 and p-Stat6.The mixed M1 and M2 cell culture induced by ToxoROP16I/III exhibited decreased production of NO and iNOS and upregulated expression of Arg-1 and PD-L2.Accordingly,Caco-2 cells became apoptotic,and apoptosis-associated proteins such as caspase-3,-8 and-9 were dampened during co-culture of M1 and M2 cells.Flow cytometry analysis showed that co-culture of M1 cells with Caco-2 cells facilitated the apoptosis of Caco-2 cells,but co-culture of M1 and M2 cells alleviated Caco-2 cell apoptosis.CONCLUSION ToxoROP16I/III-induced M2 macrophages inhibited apoptosis of Caco-2 cells caused by M1 macrophages.This finding may help gain a better understanding of the underlying mechanism and represent a promising therapeutic strategy for IBDs.
基金Supported by National Natural Science Foundation of China(General Program),No.81873203 and No.81774160.
文摘BACKGROUND The complications acute lung injury and acute kidney injury caused by severe inflammation are the main reasons of high mortality of severe acute pancreatitis(SAP).These two complications can both lead to water metabolism and acid-base balance disorders,which could act as additional critical factors affecting the disease trend.Aquaporins(AQPs),which can regulate the transmembrane water transport,have been proved to participate in the pathophysiological process of SAP and the associated complications,such as acute lung injury and acute kidney injury.Thus,exploring herbs that can effectively regulate the expression of AQP in SAP could benefit the prognosis of this disease.AIM To determine whether Yue-Bi-Tang(YBT)can regulate the water metabolism in rats with severe acute pancreatitis via regulating the expression of aquaporins.METHODS Sprague-Dawley rats were randomly divided into three groups,sham operation group(SOG),model group(MG),and treatment group(TG).SAP was induced with 3.5%sodium taurocholate in the MG and TG.Rats in the TG were administered with YBT while SOG and MG rats were given the same volume of saline.Blood and tissue samples were harvested to detect serum inflammatory cytokines,histopathological changes,malondialdehyde and superoxide dismutase in the lung,and protein and mRNA expression of kidney injury molecule-1,α-smooth muscle actin,and vimentin in the kidney,and AQP1 and 4 in the lung,pancreas,and kidney.RESULTS The serum interleukin-10,tumor necrosis factorα,and creatinine levels were higher in the MG than in the SOG.Tumor necrosis factorαlevel in the TG was lower than that in the MG.Malondialdehyde level in lung tissues was higher than in the SOG.The pathological scores and edema scores of the pancreas,lung,and kidney tissues in the MG were all higher than those in the SOG and TG.The protein expression of AQP4 in lung tissues and AQP1 in kidney tissues in the MG were higher than those in the SOG and TG.The expression of vimentin was significantly higher in the MG than in the SOG.The expression of AQP1 mRNA in the lung and kidney,and AQP4 mRNA in the kidney was up-regulated in the MG compared to the SOG.CONCLUSION YBT might regulate water metabolism to reduce lung and kidney edema of SAP rats via decreasing AQP expression,and alleviate the tissue inflammatory injury.
基金supported by key projects of the national science & technology pillar program during the eleventh five-year plan period (2008BAI58B02)danone institute China diet nutrition & comunication grant proposal 2006(DIC 2006-4)
文摘Objective The effect of dietary restriction, intense exercise and menstrual dysfunction on bone mineral density remains controversial. The aim of this study was to assess the skeletal health status and relationship between bone mineral density and nutrient intake, menstrual status, estrogen level and other factos in Chinese adolescent dancers. Methods Sixty dancers and 77 healthy controls underwent measurements of bone density, body composition, and estrogen level. Nutrient intake, menstrual status and physical activity were assessed with questionnaires. The correlation between these factors were analyzed. Results The dancers under study had a significantly lean body mass index （18.3±1.4 kg/m^2 vs. 21.7±3.1 kg/m^2）, lower percentage of body fat （0.25±0.05 vs. 0.34±0.04） and later age at menarche （14.0±0.9 y vs. 13.0±1.3 y）, and the estrogen level, daily calorie and fat intake in them were also lower than in the controls. All the dancers undertook intensive physical activity every day and up to 69% of them suffered from irregular menarche. Yet they had relatively high BMD and BMC of the total body and legs than the controls after adjusting for BM1 and age. Site-specific BMD was positively correlated to BMI, body composition and training hours per week and negatively correlated to the age at menarche and menstrual frequency. Conclusions The relatively high BMD and BMC of the dancers at the total body and legs were probably caused by high levels of weight-bearing physical activity. To ameliorate disordered eating, especially low energy intake might be helpful to prevent the Triad and to improve the bone health in adolescent dancers.
