Objectives:The antitumor effects of pyropheophorbide-αmethyl ester-mediated photodynamic therapy(MPPa-PDT)were observed in several cancers.The objective of this investigation was to examine the antineoplastic efficacy...Objectives:The antitumor effects of pyropheophorbide-αmethyl ester-mediated photodynamic therapy(MPPa-PDT)were observed in several cancers.The objective of this investigation was to examine the antineoplastic efficacy of MPPa-PDT acting on lung carcinoma A549 cells and further elaborate mechanisms.Methods:The viability of A549 cells was examined with cell counting kit-8 after MPPa-PDT disposal.Hoechst 33342 staining,monodansylcadaverine(MDC)staining,and transmission electron microscopy were employed to observe apoptotic bodies and autophagic vesicles.Flow cytometry with Annexin V/propidium iodide(PI)labeling objectively assessed cell death.The expression of associated proteins,including Caspase-3,Beclin-1,LC-3II,and mitogen-activated protein kinase(MAPK)families concluding c-jun NH2-terminal kinase(JNK),p38 MAPK,and extracellular signal-regulated kinase 1/2(ERK)were identified by Western blotting.Results:Prolonged exposure to MPPa-PDT gradually decreased lung cancer A549 cell viability.Apoptosis and autophagy activity were higher in the MPPa-PDT cohort in comparison to the control group.Meanwhile,autophagy inhibition enhanced cell-killing efficacy apparently.Besides,the JNK and p38 MAPK pathways were implicated in MPPa-PDT-triggered apoptosis and autophagy.Conclusions:This study demonstrated that JNK and p38 MAPK were engaged in MPPa-PDT-mediated apoptosis and autophagy in lung carcinoma A549 cells.展开更多
The effects of cast iron pipe corrosion onwater quality risk and microbial ecology in drinking water distribution systems(DWDSs)were investigated.It was found that trihalomethane(THMs)concentration and antibiotic resi...The effects of cast iron pipe corrosion onwater quality risk and microbial ecology in drinking water distribution systems(DWDSs)were investigated.It was found that trihalomethane(THMs)concentration and antibiotic resistance genes(ARGs)increased sharply in the old DWDSs.Under the same residual chlorine concentration conditions,the adenosine triphos-phate concentration in the effluent of old DWDSs(Eff-old)was significantly higher than that in the effluent of newDWDSs.Moreover,stronger bioflocculation ability andweaker hy-drophobicity coexisted in the extracellular polymeric substances of Eff-old,meanwhile,iron particles could be well inserted into the structure of the biofilms to enhance the mechanical strength and stability of the biofilms,hence enhancing the formation of THMs.Old DWDSs significantly influenced the microbial community of bulk water and triggered stronger mi-crobial antioxidant systems response,resulting in higher ARGs abundance.Corroded cast iron pipes induced a unique interaction system of biofilms,chlorine,and corrosion prod-ucts.Therefore,as the age of cast iron pipes increases,the fluctuation of water quality and microbial ecology should be paid more attention to maintain the safety of tap water.展开更多
With rapid development of UAV technology,research on UAV image analysis has gained attention.As the existing techniques of UAV target localization often rely on additional equipment,a method of UAV target localization...With rapid development of UAV technology,research on UAV image analysis has gained attention.As the existing techniques of UAV target localization often rely on additional equipment,a method of UAV target localization based on depth estimation has been proposed.However,the unique perspective of UAVs poses challenges such as the significant field of view variations and the presence of dynamic objects in the scene.As a result,the existing methods of depth estimation and scale recovery cannot be directly applied to UAV perspectives.Additionally,there is a scarcity of depth estimation datasets tailored for UAV perspectives,which makes supervised algorithms impractical.To address these issues,an outlier filter is introduced to enhance the applicability of depth estimation networks to target localization.A frame buffer method is proposed to achieve more accurate scale recovery,so as to handle complex scene textures in UAV images.The proposed method demonstrates a 14.29%improvement over the baseline.Compared with the average recovery results from UAV perspectives,the difference is only 0.88%,approaching the performance of scale recovery using ground truth labels.Furthermore,to overcome the limited availability of traditional UAV depth datasets,a method for generating depth labels from video sequences is proposed.Compared to state-of-the-art methods,the proposed approach achieves higher accuracy in depth estimation and stands for the first attempt at target localization using image sequences.Proposed algorithm and dataset are available at https://github.com/uav-tan/uav-object-localization.展开更多
This study aimed to investigate aquaporin 4 expression and the ultrastructure of the blood-brain barrier at 2-72 hours following cerebral contusion injury, and correlate these changes to the formation of brain edema. ...This study aimed to investigate aquaporin 4 expression and the ultrastructure of the blood-brain barrier at 2-72 hours following cerebral contusion injury, and correlate these changes to the formation of brain edema. Results revealed that at 2 hours after cerebral contusion and laceration injury, aquaporin 4 expression significantly increased, brain water content and blood-brain barrier permeability increased, and the number of pinocytotic vesicles in cerebral microvascular endothelia cells increased. In addition, the mitochondrial accumulation was observed. As contusion and laceration injury became aggravated, aquaporin 4 expression continued to increase, brain water content and blood-brain barrier permeability gradually increased, brain capillary endothelial cells and astrocytes swelled, and capillary basement membrane injury gradually increased. The above changes were most apparent at 12 hours after injury, after which they gradually attenuated. Aquaporin 4 expression positively correlated with brain water content and the blood-brain barrier index. Our experimental findings indicate that increasing aquaporin 4 expression and blood-brain barrier permeability after cerebral contusion and laceration injury in humans is involved in the formation of brain edema.展开更多
BACKGROUND： Previous studies have demonstrated that homocysteine is an independent risk factor for ischemic stroke, as determined by detection of apoptosis and oxygen-free radical scavengers following cerebral ischem...BACKGROUND： Previous studies have demonstrated that homocysteine is an independent risk factor for ischemic stroke, as determined by detection of apoptosis and oxygen-free radical scavengers following cerebral ischemia. However, the mechanisms of homocysteine remain unclear Several reports have addressed the effects of homocysteine on ischemic stroke. OBJECTIVE： To analyze the effects of homocysteine on apoptosis, intracellular superoxide dismutase （SOD） activity, and malondialdehyde content in tissue surrounding hematoma in rats with cerebral hemorrhage, and to determine the action pathway of malondialdehyde following cerebral hemorrhage. DESIGN, TIME AND SETTING： The randomized, controlled, animal experiment was performed at the Laboratory of Molecular Biology, Hospital Affiliated to Luzhou Medical College, China from April 2007 to April 2008. MATERIALS： In situ apoptosis detection kit （Roche, Mannheim, Germany）, SOD detection kit and malondialdehyde detection kit （Nanjing Jiancheng Bioengineering Institute, China）, and homocysteine （Sigma, St Louis, MO, USA） were used in the present study. METHODS： A total of 75 Sprague Dawley rats were equally and randomly assigned to sham surgery model, and homocysteine groups. Autologous blood was infused into the caudate putamen of rats to establish models of cerebral hemorrhage in model and homocysteine groups. Homocysteine was injected directly into the brain through the skull at the hematoma hemisphere at 30 minutes after model induction in the homocysteine group. MAIN OUTCOME MEASURES： At 6, 12, 24, and 72 hours, as well as 1 week, post-surgery, neurological deficits were observed in each group. Brain water content was measured using the dry-wet weight method. Cell apoptosis in tissue surrounding the hematoma was detected utilizing terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling （TUNEL）. SOD activity and malondialdehyde content in tissue surrounding the hematoma were respectively measured using the xanthine oxidase and thiobarbituric acid methods. RESULTS： Neurological function was similar between model and homocysteine groups following cerebral hemorrhage （P 〉 0.05）. Brain water content was increased at 12 hours post-surgery, peaked at 3 days, and remained unchanged at 7 days in the model group. Brain edema was not significantly aggravated following homocysteine intervention （P 〉 0.05）, but SOD activity significantly decreased and malondialdehyde content significantly increased （P 〈 0.05）. The number of apoptotic cells increased in rats with cerebral hemorrhage at 12 hours （P 〈 0.05）, and numbers peaked at 72 hours following model establishment （P〈 0.05）. The time of peak value was identical between model and homocysteine groups. Brain water content was negatively associated with SOD activity （rmodel group =-0.448, P 〈 0.05; rhomocysteine group =-0.612, P 〈 0.05）, but was positively associated with malondialdehyde content （rmodel group = 0.542, P 〈 0.05; rhomocysteine group = 0.684, P 〈 0.05） in brain tissues surrounding the hematoma following surgery in model and homocysteine groups. CONCLUSION： Homocysteine aggravates neurological dysfunction and brain edema in rats with cerebral hemorrhage. The mechanisms of action are likely associated with production of oxygen-free radical and cellular apoptosis following cerebral hemorrhage.展开更多
In the field of developmental neurobiology, accurate and ordered regulation of the cell cycle and apoptosis are crucial factors contributing to the normal formation of the neural tube. Preliminary studies identified s...In the field of developmental neurobiology, accurate and ordered regulation of the cell cycle and apoptosis are crucial factors contributing to the normal formation of the neural tube. Preliminary studies identified several genes involved in the development of neural tube defects. In this study, we established a model of developmental neural tube defects by administration of retinoic acid to pregnant rats. Gene chip hybridization analysis showed that genes related to the cell cycle and apoptosis, signal transduction, transcription and translation regulation, energy and metabolism, heat shock, and matrix and cytoskeletal proteins were all involved in the formation of developmental neural tube defects. Among these, cell cycle-related genes were predominant. Retinoic acid treat-ment caused differential expression of three cell cycle-related genes p57kip2, Cdk5 and Spin, the expression levels of which were downregulated by retinoic acid and upregulated during normal neural tube formation. The results of this study indicate that cell cycle-related genes play an im-portant role in the formation of neural tube defects. P57kip2, Cdk5 and Spin may be critical genes in the pathogenesis of neural tube defects.展开更多
To date, little information has been available regarding genes involved in the regulation of embryonic cell development, which participate in retinoic acid-induced neural tube defects in mice. Previous studies have re...To date, little information has been available regarding genes involved in the regulation of embryonic cell development, which participate in retinoic acid-induced neural tube defects in mice. Previous studies have revealed seven differentially expressed genes involved in neural tube developmental defects. However, gene expression and regulation is a complex process. Therefore, gene expression differences between normal and defective neural tubes at 9.5 and 10.5 days were compared. A total of eight differentially expressed genes exhibited coincident alterations at embryonic 9.5 and 10.5 days. In mice with retinoic acid-induced neural tube defects, NeK7, IGFBP5 ZW10, Csf3r, PSMC6, Cdk5, and Rbl expressions were downregulated, but Apoa-4 expression was upregulated. These results were confirmed by Northern blot hybridization. Results suggested that NeK7, IGFBP5, ZW10, Csf3r, PSMC6, Cdk5, Rb1, and Apoa-4 are important regulatory factors involved in neural tube defects.展开更多
BACKGROUND： Several studies have shown that midkine directly participates in tumor cell growth and invasion, as well as the regulation of angiogenesis. OBJECTIVE： To investigate midkine expression in meningioma tiss...BACKGROUND： Several studies have shown that midkine directly participates in tumor cell growth and invasion, as well as the regulation of angiogenesis. OBJECTIVE： To investigate midkine expression in meningioma tissue in relation to angiogenesis, invasion, peritumoral edema, and clinicopathology. DESIGN, TIME AND SETTING： The present clinical, case-controlled, neuropathological study was performed at the Laboratory of Molecular Organism, People＇s Hospital of Deyang City between May 2007 and April 2008. MATERIALS： Fifty-two meningioma tissues were classified by WHO tumor classification of the central nervous system, comprising 40 grade Ⅰ meningioma, five grade Ⅱ meningioma, and seven grade Ⅲ meningioma. Ten normal, human cerebral maters were selected from cerebral trauma patients. METHODS： Midkine protein expression and mean microvessel density were detected using immunohistochemical techniques. Simultaneously, all data were statistically analyzed. MAIN OUTCOME MEASURES： Midkine expression and microvessel density in meningiomas and normal cerebral maters. RESULTS： The positive midkine expression rate was 64% in the meningioma tissues. However, midkine expression was not detected in normal cerebral mater tissue. The mean microvessel density was 82.0 ± 22.7 in the meningiomas, and 25.8± 6.2 in the normal cerebral mater tissues. There was significant difference in midkine expression and mean microvessel density between meningioma tissues and human cerebral maters （P 〈 0.05）. Midkine expression positively correlated with microvessel density （r = 0.756, P 〈 0.05）. Midkine expression did not correlate to patient age, gender, or tumor size, location, and shape （P 〉 0.05）. However, it closely correlated with patient clinical condition, pathological grade, invasion, and peritumoral edema （r = 0.3785,0.741 2,0.6518, 0.614 2, P 〈 0.05）. CONCLUSION： Midkine protein was overexpressed in meningiomas and correlated to tumor angiogenesis, invasion, pefitumoral edema, and clinicopathology.展开更多
The thermal comfort of passengers in the carriage cannot be ignored.Thus,this research aims to establish a prediction model for the thermal comfort of the internal environment of a subway car and find the optimal inpu...The thermal comfort of passengers in the carriage cannot be ignored.Thus,this research aims to establish a prediction model for the thermal comfort of the internal environment of a subway car and find the optimal input combination in establishing the prediction model of the predicted mean vote(PMV)index.Data-driven modeling utilizes data from experiments and questionnaires conducted in Nanjing Metro.Support vector machine(SVM),decision tree(DT),random forest(RF),and logistic regression(LR)were used to build four models.This research aims to select the most appropriate input variables for the predictive model.All possible combinations of 11 input variables were used to determine the most accurate model,with variable selection for each model comprising 102350 iterations.In the PMV prediction,the RF model was the best when using the correlation coefficients square(R2)as the evaluation indicator(R^(2):0.7680,mean squared error(MSE):0.2868).The variables include clothing temperature(CT),convective heat transfer coefficient between the surface of the human body and the environment(CHTC),black bulb temperature(BBT),and thermal resistance of clothes(TROC).The RF model with MSE as the evaluation index also had the highest accuracy(R^(2):0.7676,MSE:0.2836).The variables include clothing surface area coefficient(CSAC),CT,BBT,and air velocity(AV).The results show that the RF model can efficiently predict the PMV of the subway car environment.展开更多
To promote the application of bio-materials and provide a direction for their further researches,this paper comprehensively summarizes the research progress of biomaterials in recent years.The review results show that...To promote the application of bio-materials and provide a direction for their further researches,this paper comprehensively summarizes the research progress of biomaterials in recent years.The review results show that bio-oil is a mixture obtained from different biomasses through pyrolysis,alcoholysis,acidolysis,high liquefaction,etc.,and those biomasses mainly include wood fiber type,waste oil type and animal manure type.Biobinder refers to the product of bio-oil processed by distillation,extraction oxidation and polymer modification,and it can be served as a modifier,diluent or substitute material of asphalt;the main chemical components of bio-oil include ethers,esters,aldehydes,ketones,phenols,organic acids,alcohols and sugars.Bio-asphalt is obtained by adding biobinder into the petroleum asphalt for modification or blending,and the shear temperature and shear rate of bio-asphalt derived from wood fiber type and waste oil type are usually higher than that of bio-asphalt derived from swine manure.Compared with petroleum asphalt,bio-asphalt binder usually shows lower high-temperature performance as well as higher low-temperature performance and aging resistance.Also,bio-asphalt mixture generally exhibits lower high-temperature stability,higher low-temperature crack resistance and water stability than petroleum asphalt mixture.Future studies should be conducted combining with the source,composition,preparation,properties and oil production rate of bio-oil.First,how to raise the bio-binder content in bio-asphalt as much as possible while ensuring the sufficient performance becomes the focus of future researches.Second,the micro reaction mechanism between bio-binder and petroleum asphalt should be illustrated in depth.Moreover,developing a complete and unifying technical standard and application specification of bio-asphalt technology is necessary for future researches.Furthermore,determining the optimum bio-binder potentially used as the substitute of petroleum asphalt is also an interesting topic.展开更多
Nb-doped TiO2 nanoparticles were prepared by hydrothermal treatment of titanate nanotubes in niobium oxalate aqueous solution.The effect of Nb doping and rutile content on the photoelectrochemical performance based on...Nb-doped TiO2 nanoparticles were prepared by hydrothermal treatment of titanate nanotubes in niobium oxalate aqueous solution.The effect of Nb doping and rutile content on the photoelectrochemical performance based on TiO2 powder electrodes was investigated.The results show that Nb-doped TiO2 with a small amount of rutile exhibits the enhanced photoelectric conversion efficiency for dye-sensitized solar cell.The highest photoelectric conversion efficiency of 8.53%is obtained for 1%Nb—TiO2 containing a small amount of rutile.When a small amount of rutile contained in 2%Nb—TiO2,a higher photoelectric conversion efficiency of8.77%is achieved.展开更多
Rutile TiO2 nanowire array films with multi-walled carbon nanotube （MWCNT） inclusion perpendicularly grown on fluorine-doped tin oxide （FTO） substrate were prepared by a facile hydrothermal method. The absorption ...Rutile TiO2 nanowire array films with multi-walled carbon nanotube （MWCNT） inclusion perpendicularly grown on fluorine-doped tin oxide （FTO） substrate were prepared by a facile hydrothermal method. The absorption edges of the TiO2 nanowire array films are blue-shifted with increasing MWCNT content. The resistance of the TiO2 nanowire array film is decreased by MWCNT inclusion. The optimum TiO2/MWCNT molar ratio in the feedstock is 1：0.1. For the TiO2 nanowire array film with MWCNT inclusion served as electrode in dye-sensitized solar cell （DSSC）, an overall 194% increase of photoelectric conversion efficiency has been achieved.展开更多
基金supported by XiaoganCity Natural Science Foundation of China (Grant/AwardNo. XGKJ2022010004).
文摘Objectives:The antitumor effects of pyropheophorbide-αmethyl ester-mediated photodynamic therapy(MPPa-PDT)were observed in several cancers.The objective of this investigation was to examine the antineoplastic efficacy of MPPa-PDT acting on lung carcinoma A549 cells and further elaborate mechanisms.Methods:The viability of A549 cells was examined with cell counting kit-8 after MPPa-PDT disposal.Hoechst 33342 staining,monodansylcadaverine(MDC)staining,and transmission electron microscopy were employed to observe apoptotic bodies and autophagic vesicles.Flow cytometry with Annexin V/propidium iodide(PI)labeling objectively assessed cell death.The expression of associated proteins,including Caspase-3,Beclin-1,LC-3II,and mitogen-activated protein kinase(MAPK)families concluding c-jun NH2-terminal kinase(JNK),p38 MAPK,and extracellular signal-regulated kinase 1/2(ERK)were identified by Western blotting.Results:Prolonged exposure to MPPa-PDT gradually decreased lung cancer A549 cell viability.Apoptosis and autophagy activity were higher in the MPPa-PDT cohort in comparison to the control group.Meanwhile,autophagy inhibition enhanced cell-killing efficacy apparently.Besides,the JNK and p38 MAPK pathways were implicated in MPPa-PDT-triggered apoptosis and autophagy.Conclusions:This study demonstrated that JNK and p38 MAPK were engaged in MPPa-PDT-mediated apoptosis and autophagy in lung carcinoma A549 cells.
基金supported by the National Natural Science Foundation of China(Nos.52000043,and 51838005)the intro-duced innovative R&D team project under the“The Pearl River Talent Recruitment Program”of Guangdong Province(No.2019ZT08L387)+2 种基金the Guangdong Natural Science Foundation(No.2023A1515011509)the Science and Technology Research Project of Guangzhou(Nos.202201020177,202102020986 and 202102021044)the special fund from Key Laboratory of Drinking Water Science and Technology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences(No.20K01KLDWST).
文摘The effects of cast iron pipe corrosion onwater quality risk and microbial ecology in drinking water distribution systems(DWDSs)were investigated.It was found that trihalomethane(THMs)concentration and antibiotic resistance genes(ARGs)increased sharply in the old DWDSs.Under the same residual chlorine concentration conditions,the adenosine triphos-phate concentration in the effluent of old DWDSs(Eff-old)was significantly higher than that in the effluent of newDWDSs.Moreover,stronger bioflocculation ability andweaker hy-drophobicity coexisted in the extracellular polymeric substances of Eff-old,meanwhile,iron particles could be well inserted into the structure of the biofilms to enhance the mechanical strength and stability of the biofilms,hence enhancing the formation of THMs.Old DWDSs significantly influenced the microbial community of bulk water and triggered stronger mi-crobial antioxidant systems response,resulting in higher ARGs abundance.Corroded cast iron pipes induced a unique interaction system of biofilms,chlorine,and corrosion prod-ucts.Therefore,as the age of cast iron pipes increases,the fluctuation of water quality and microbial ecology should be paid more attention to maintain the safety of tap water.
基金financial support from the National Key Research and Development Program of China (Nos. 2022YFB3904303 and 2020YFB0505602)the National Natural Science Foundation of China (Nos. 62076019, 62022012, U2233217, 62101019 and 62371029)the Civil Aviation Security Capacity Building Fund Project, China (Nos. CAAC Contract 2020(123), CAAC Contract 2021(77) and CAAC Contract 2022(110))
文摘With rapid development of UAV technology,research on UAV image analysis has gained attention.As the existing techniques of UAV target localization often rely on additional equipment,a method of UAV target localization based on depth estimation has been proposed.However,the unique perspective of UAVs poses challenges such as the significant field of view variations and the presence of dynamic objects in the scene.As a result,the existing methods of depth estimation and scale recovery cannot be directly applied to UAV perspectives.Additionally,there is a scarcity of depth estimation datasets tailored for UAV perspectives,which makes supervised algorithms impractical.To address these issues,an outlier filter is introduced to enhance the applicability of depth estimation networks to target localization.A frame buffer method is proposed to achieve more accurate scale recovery,so as to handle complex scene textures in UAV images.The proposed method demonstrates a 14.29%improvement over the baseline.Compared with the average recovery results from UAV perspectives,the difference is only 0.88%,approaching the performance of scale recovery using ground truth labels.Furthermore,to overcome the limited availability of traditional UAV depth datasets,a method for generating depth labels from video sequences is proposed.Compared to state-of-the-art methods,the proposed approach achieves higher accuracy in depth estimation and stands for the first attempt at target localization using image sequences.Proposed algorithm and dataset are available at https://github.com/uav-tan/uav-object-localization.
文摘This study aimed to investigate aquaporin 4 expression and the ultrastructure of the blood-brain barrier at 2-72 hours following cerebral contusion injury, and correlate these changes to the formation of brain edema. Results revealed that at 2 hours after cerebral contusion and laceration injury, aquaporin 4 expression significantly increased, brain water content and blood-brain barrier permeability increased, and the number of pinocytotic vesicles in cerebral microvascular endothelia cells increased. In addition, the mitochondrial accumulation was observed. As contusion and laceration injury became aggravated, aquaporin 4 expression continued to increase, brain water content and blood-brain barrier permeability gradually increased, brain capillary endothelial cells and astrocytes swelled, and capillary basement membrane injury gradually increased. The above changes were most apparent at 12 hours after injury, after which they gradually attenuated. Aquaporin 4 expression positively correlated with brain water content and the blood-brain barrier index. Our experimental findings indicate that increasing aquaporin 4 expression and blood-brain barrier permeability after cerebral contusion and laceration injury in humans is involved in the formation of brain edema.
文摘BACKGROUND： Previous studies have demonstrated that homocysteine is an independent risk factor for ischemic stroke, as determined by detection of apoptosis and oxygen-free radical scavengers following cerebral ischemia. However, the mechanisms of homocysteine remain unclear Several reports have addressed the effects of homocysteine on ischemic stroke. OBJECTIVE： To analyze the effects of homocysteine on apoptosis, intracellular superoxide dismutase （SOD） activity, and malondialdehyde content in tissue surrounding hematoma in rats with cerebral hemorrhage, and to determine the action pathway of malondialdehyde following cerebral hemorrhage. DESIGN, TIME AND SETTING： The randomized, controlled, animal experiment was performed at the Laboratory of Molecular Biology, Hospital Affiliated to Luzhou Medical College, China from April 2007 to April 2008. MATERIALS： In situ apoptosis detection kit （Roche, Mannheim, Germany）, SOD detection kit and malondialdehyde detection kit （Nanjing Jiancheng Bioengineering Institute, China）, and homocysteine （Sigma, St Louis, MO, USA） were used in the present study. METHODS： A total of 75 Sprague Dawley rats were equally and randomly assigned to sham surgery model, and homocysteine groups. Autologous blood was infused into the caudate putamen of rats to establish models of cerebral hemorrhage in model and homocysteine groups. Homocysteine was injected directly into the brain through the skull at the hematoma hemisphere at 30 minutes after model induction in the homocysteine group. MAIN OUTCOME MEASURES： At 6, 12, 24, and 72 hours, as well as 1 week, post-surgery, neurological deficits were observed in each group. Brain water content was measured using the dry-wet weight method. Cell apoptosis in tissue surrounding the hematoma was detected utilizing terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling （TUNEL）. SOD activity and malondialdehyde content in tissue surrounding the hematoma were respectively measured using the xanthine oxidase and thiobarbituric acid methods. RESULTS： Neurological function was similar between model and homocysteine groups following cerebral hemorrhage （P 〉 0.05）. Brain water content was increased at 12 hours post-surgery, peaked at 3 days, and remained unchanged at 7 days in the model group. Brain edema was not significantly aggravated following homocysteine intervention （P 〉 0.05）, but SOD activity significantly decreased and malondialdehyde content significantly increased （P 〈 0.05）. The number of apoptotic cells increased in rats with cerebral hemorrhage at 12 hours （P 〈 0.05）, and numbers peaked at 72 hours following model establishment （P〈 0.05）. The time of peak value was identical between model and homocysteine groups. Brain water content was negatively associated with SOD activity （rmodel group =-0.448, P 〈 0.05; rhomocysteine group =-0.612, P 〈 0.05）, but was positively associated with malondialdehyde content （rmodel group = 0.542, P 〈 0.05; rhomocysteine group = 0.684, P 〈 0.05） in brain tissues surrounding the hematoma following surgery in model and homocysteine groups. CONCLUSION： Homocysteine aggravates neurological dysfunction and brain edema in rats with cerebral hemorrhage. The mechanisms of action are likely associated with production of oxygen-free radical and cellular apoptosis following cerebral hemorrhage.
基金supported by the Science and Technology Key Program of Sichuan Provincial Health Ministry,No.080128
文摘In the field of developmental neurobiology, accurate and ordered regulation of the cell cycle and apoptosis are crucial factors contributing to the normal formation of the neural tube. Preliminary studies identified several genes involved in the development of neural tube defects. In this study, we established a model of developmental neural tube defects by administration of retinoic acid to pregnant rats. Gene chip hybridization analysis showed that genes related to the cell cycle and apoptosis, signal transduction, transcription and translation regulation, energy and metabolism, heat shock, and matrix and cytoskeletal proteins were all involved in the formation of developmental neural tube defects. Among these, cell cycle-related genes were predominant. Retinoic acid treat-ment caused differential expression of three cell cycle-related genes p57kip2, Cdk5 and Spin, the expression levels of which were downregulated by retinoic acid and upregulated during normal neural tube formation. The results of this study indicate that cell cycle-related genes play an im-portant role in the formation of neural tube defects. P57kip2, Cdk5 and Spin may be critical genes in the pathogenesis of neural tube defects.
基金Scientific and Technological Projects of Sichuan Provincial Health Department, No. 080128
文摘To date, little information has been available regarding genes involved in the regulation of embryonic cell development, which participate in retinoic acid-induced neural tube defects in mice. Previous studies have revealed seven differentially expressed genes involved in neural tube developmental defects. However, gene expression and regulation is a complex process. Therefore, gene expression differences between normal and defective neural tubes at 9.5 and 10.5 days were compared. A total of eight differentially expressed genes exhibited coincident alterations at embryonic 9.5 and 10.5 days. In mice with retinoic acid-induced neural tube defects, NeK7, IGFBP5 ZW10, Csf3r, PSMC6, Cdk5, and Rbl expressions were downregulated, but Apoa-4 expression was upregulated. These results were confirmed by Northern blot hybridization. Results suggested that NeK7, IGFBP5, ZW10, Csf3r, PSMC6, Cdk5, Rb1, and Apoa-4 are important regulatory factors involved in neural tube defects.
文摘BACKGROUND： Several studies have shown that midkine directly participates in tumor cell growth and invasion, as well as the regulation of angiogenesis. OBJECTIVE： To investigate midkine expression in meningioma tissue in relation to angiogenesis, invasion, peritumoral edema, and clinicopathology. DESIGN, TIME AND SETTING： The present clinical, case-controlled, neuropathological study was performed at the Laboratory of Molecular Organism, People＇s Hospital of Deyang City between May 2007 and April 2008. MATERIALS： Fifty-two meningioma tissues were classified by WHO tumor classification of the central nervous system, comprising 40 grade Ⅰ meningioma, five grade Ⅱ meningioma, and seven grade Ⅲ meningioma. Ten normal, human cerebral maters were selected from cerebral trauma patients. METHODS： Midkine protein expression and mean microvessel density were detected using immunohistochemical techniques. Simultaneously, all data were statistically analyzed. MAIN OUTCOME MEASURES： Midkine expression and microvessel density in meningiomas and normal cerebral maters. RESULTS： The positive midkine expression rate was 64% in the meningioma tissues. However, midkine expression was not detected in normal cerebral mater tissue. The mean microvessel density was 82.0 ± 22.7 in the meningiomas, and 25.8± 6.2 in the normal cerebral mater tissues. There was significant difference in midkine expression and mean microvessel density between meningioma tissues and human cerebral maters （P 〈 0.05）. Midkine expression positively correlated with microvessel density （r = 0.756, P 〈 0.05）. Midkine expression did not correlate to patient age, gender, or tumor size, location, and shape （P 〉 0.05）. However, it closely correlated with patient clinical condition, pathological grade, invasion, and peritumoral edema （r = 0.3785,0.741 2,0.6518, 0.614 2, P 〈 0.05）. CONCLUSION： Midkine protein was overexpressed in meningiomas and correlated to tumor angiogenesis, invasion, pefitumoral edema, and clinicopathology.
文摘The thermal comfort of passengers in the carriage cannot be ignored.Thus,this research aims to establish a prediction model for the thermal comfort of the internal environment of a subway car and find the optimal input combination in establishing the prediction model of the predicted mean vote(PMV)index.Data-driven modeling utilizes data from experiments and questionnaires conducted in Nanjing Metro.Support vector machine(SVM),decision tree(DT),random forest(RF),and logistic regression(LR)were used to build four models.This research aims to select the most appropriate input variables for the predictive model.All possible combinations of 11 input variables were used to determine the most accurate model,with variable selection for each model comprising 102350 iterations.In the PMV prediction,the RF model was the best when using the correlation coefficients square(R2)as the evaluation indicator(R^(2):0.7680,mean squared error(MSE):0.2868).The variables include clothing temperature(CT),convective heat transfer coefficient between the surface of the human body and the environment(CHTC),black bulb temperature(BBT),and thermal resistance of clothes(TROC).The RF model with MSE as the evaluation index also had the highest accuracy(R^(2):0.7676,MSE:0.2836).The variables include clothing surface area coefficient(CSAC),CT,BBT,and air velocity(AV).The results show that the RF model can efficiently predict the PMV of the subway car environment.
基金supported by the Key Research and Development Program of Shaanxi Province(Grant No.2022SF-169)。
文摘To promote the application of bio-materials and provide a direction for their further researches,this paper comprehensively summarizes the research progress of biomaterials in recent years.The review results show that bio-oil is a mixture obtained from different biomasses through pyrolysis,alcoholysis,acidolysis,high liquefaction,etc.,and those biomasses mainly include wood fiber type,waste oil type and animal manure type.Biobinder refers to the product of bio-oil processed by distillation,extraction oxidation and polymer modification,and it can be served as a modifier,diluent or substitute material of asphalt;the main chemical components of bio-oil include ethers,esters,aldehydes,ketones,phenols,organic acids,alcohols and sugars.Bio-asphalt is obtained by adding biobinder into the petroleum asphalt for modification or blending,and the shear temperature and shear rate of bio-asphalt derived from wood fiber type and waste oil type are usually higher than that of bio-asphalt derived from swine manure.Compared with petroleum asphalt,bio-asphalt binder usually shows lower high-temperature performance as well as higher low-temperature performance and aging resistance.Also,bio-asphalt mixture generally exhibits lower high-temperature stability,higher low-temperature crack resistance and water stability than petroleum asphalt mixture.Future studies should be conducted combining with the source,composition,preparation,properties and oil production rate of bio-oil.First,how to raise the bio-binder content in bio-asphalt as much as possible while ensuring the sufficient performance becomes the focus of future researches.Second,the micro reaction mechanism between bio-binder and petroleum asphalt should be illustrated in depth.Moreover,developing a complete and unifying technical standard and application specification of bio-asphalt technology is necessary for future researches.Furthermore,determining the optimum bio-binder potentially used as the substitute of petroleum asphalt is also an interesting topic.
基金supported by the National Natural Science Foundation of China(No.51172233)the Major State Basic Research Development Program of China("973 Program",No. 2009CB220002)the Key Laboratory of Water and Air Pollution Control of Guandong Province,China(GD2012A05)
文摘Nb-doped TiO2 nanoparticles were prepared by hydrothermal treatment of titanate nanotubes in niobium oxalate aqueous solution.The effect of Nb doping and rutile content on the photoelectrochemical performance based on TiO2 powder electrodes was investigated.The results show that Nb-doped TiO2 with a small amount of rutile exhibits the enhanced photoelectric conversion efficiency for dye-sensitized solar cell.The highest photoelectric conversion efficiency of 8.53%is obtained for 1%Nb—TiO2 containing a small amount of rutile.When a small amount of rutile contained in 2%Nb—TiO2,a higher photoelectric conversion efficiency of8.77%is achieved.
基金supported by the National Natural Science Foundation of China (Grant No.51172233)the National Basic Research Program of China ("973 Program",Grant No.2009CB220002)
文摘Rutile TiO2 nanowire array films with multi-walled carbon nanotube （MWCNT） inclusion perpendicularly grown on fluorine-doped tin oxide （FTO） substrate were prepared by a facile hydrothermal method. The absorption edges of the TiO2 nanowire array films are blue-shifted with increasing MWCNT content. The resistance of the TiO2 nanowire array film is decreased by MWCNT inclusion. The optimum TiO2/MWCNT molar ratio in the feedstock is 1：0.1. For the TiO2 nanowire array film with MWCNT inclusion served as electrode in dye-sensitized solar cell （DSSC）, an overall 194% increase of photoelectric conversion efficiency has been achieved.
