To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure,a quasiperiodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise reduction...To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure,a quasiperiodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise reduction.The arrangement of the elastic support element is determined by the equivalent periodic distance and quasi-periodic coefficient.In this paper,a dynamic model of skin in a fluid environment is established.The influence of equivalent periodic distance and quasi-periodic coefficient on flow stability is investigated.The results suggest that arranging the elastic support elements in accordance with the quasi-periodic law can effectively enhance flow stability.Meanwhile,the hydrodynamic noise calculation results demonstrate that the skin exhibits excellent noise reduction performance,with reductions of 10 dB in the streamwise direction,11 dB in the spanwise direction,and 10 dB in the normal direction.The results also demonstrate that the stability analysis method can serve as a diagnostic tool for flow fields and guide the design of noise reduction structures.展开更多
Danhong injection(DHI),a Chinese Materia Medica standardized product extracted from Radix Salviae miltiorrhizae and Flos Carthami tinctorii,is widely used in China for treating acute ischemic stroke.In the present stu...Danhong injection(DHI),a Chinese Materia Medica standardized product extracted from Radix Salviae miltiorrhizae and Flos Carthami tinctorii,is widely used in China for treating acute ischemic stroke.In the present study,we explored the neuroprotective efficacy of DHI in a rat model of temporary middle cerebral artery occlusion,and evaluated the potential mechanisms underlying its effects.Pretreatment with DHI(0.9 and 1.8 mL/kg)resulted in a significantly smaller infarct volume and better neurological scores than pretreatment with saline.Furthermore,DHI significantly reduced the permeability of the blood-brain barrier,increased occludin protein expression and decreased neutrophil infiltration,as well as profoundly suppressing the upregulation of matrix metallopeptidase-9 expression seen in rats that had received vehicle.Matrix metallopeptidase-2 expression was not affected by ischemia or DHI.Moreover,DHI(1.8 mL/kg)administered 3 hours after the onset of ischemia also improved neurological scores and reduced infarct size.Our results indicate that the neuroprotective efficacy of DHI in a rat model of cerebral ischemia-reperfusion injury is mediated by a protective effect on the blood-brain barrier and the reversal of neutrophil infiltration.展开更多
A solid-state electrolyte(SSE),which is a solid ionic conductor and electroninsulating material,is known to play a crucial role in adapting a lithium metal anode to a high-capacity cathode in a solid-state battery.Amo...A solid-state electrolyte(SSE),which is a solid ionic conductor and electroninsulating material,is known to play a crucial role in adapting a lithium metal anode to a high-capacity cathode in a solid-state battery.Among the various SSEs,the single Li-ion conductor has advantages in terms of enhancing the ion conductivity,eliminating interfacial side reactions,and broadening the electrochemical window.Covalent organic frameworks(COFs)are optimal platforms for achieving single Li-ion conduction behavior because of wellordered one-dimensional channels and precise chemical modification features.Herein,we study in depth three types of Li-carboxylate COFs(denoted LiOOC-COFn,n=1,2,and 3)as single Li-ion conducting SSEs.Benefiting from well-ordered directional ion channels,the single Li-ion conductor LiOOC-COF3 shows an exceptional ion conductivity of 1.36×10^(-5) S cm^(-1) at room temperature and a high transference number of 0.91.Moreover,it shows excellent electrochemical performance with long-term cycling,high-capacity output,and no dendrites in the quasi-solid-state organic battery,with the organic small molecule cyclohexanehexone(C_(6)O_(6))as the cathode and the Li metal as the anode,and enables effectively avoiding dissolution of the organic electrode by the liquid electrolyte.展开更多
Lithium metal batteries(LMBs)have attracted wide attentions because of their high theoretical specific capacity and low electrochemical potential.However,the growth of lithium dendrites seriously affects the practical...Lithium metal batteries(LMBs)have attracted wide attentions because of their high theoretical specific capacity and low electrochemical potential.However,the growth of lithium dendrites seriously affects the practical application of LMBs.Thus,the lithium-philic carbonyl and carboxy dualgroup-modified covalent organic framework(COF-COOH)is designed to coat the polypropylene(PP)separator(COF-COOH@PP separator),realizing the regulation of ion transport and uniform lithium deposition.The plentiful and negative charge sites in the COF-COOH can suppress the diffusion of the freely movable lithium salt anion by the electrostatic interaction.Density functional theory(DFT)calculations demonstrate that the COF-COOH possesses the function of anchoring anion and desolvation.Consequently,the Li^(+)transference number(0.7),ion conductivity(0.64 mS cm^(-1)),and desolvating of Li^(+)are obviously improved by using the COF-COOH@PP separator.The modified Li-Li symmetric battery delivers stable cycle for more than 1000 h and lower voltage hysteresis(0.02 V).This dendrite-free deposition strategy holds great promise for practical application of Li metal anodes.展开更多
Micrometric-thin cells(MCs)with alkali vapor atoms have been valuable for research and applications of hyperfine Zeeman splitting and atomic magnetometers under strong magnetic fields.We theoretically and experimental...Micrometric-thin cells(MCs)with alkali vapor atoms have been valuable for research and applications of hyperfine Zeeman splitting and atomic magnetometers under strong magnetic fields.We theoretically and experimentally study the saturated absorption spectra using a 100-μm cesium MC,where the pump and probe beams are linearly polarized with mutually perpendicular polarizations,and the magnetic field is along the pump beam.Because of the distinctive thin chamber of the MC,crossover spectral lines in saturated absorption spectra are largely suppressed leading to clear splittings of hyperfine Zeeman transitions in experiments,and the effect of spatial magnetic field gradient is expected to be reduced.A calculation method is proposed to achieve good agreements between theoretical calculations and experimental results.This method successfully explains the suppression of crossover lines in MCs,as well as the effects of magnetic field direction,propagation and polarization directions of the pump/probe beam on saturated absorption spectrum.The saturated absorption spectrum with suppressed crossover lines is used for laser frequency stabilization,which may provide the potential value of MCs for high spatial resolution strong-field magnetometry with high sensitivity.展开更多
BACKGROUND In patients with post-stroke depression(PSD)in diabetes,the situation may be more complex,requiring simultaneous treatment of blood glucose,depressive symptoms,and neurological dysfunction.Hyperbaric oxygen...BACKGROUND In patients with post-stroke depression(PSD)in diabetes,the situation may be more complex,requiring simultaneous treatment of blood glucose,depressive symptoms,and neurological dysfunction.Hyperbaric oxygen(HBO)therapy can improve tissue oxygen content and improve the situation of ischemia and hypoxia,thus playing a role in protecting brain cells and restoring the function of brain cells.However,there are few studies on HBO therapy for patients with PSD.This study explores the clinical efficacy of such therapy for stroke complicated with depression and diabetes mellitus,and to provide reference and basis for clinical treatment and development through the application of relevant rating scales and laboratory test indicators.AIM To evaluate the clinical effects of HBO therapy on patients with diabetes with PSD.METHODS A total of 190 diabetic patients with PSD were randomly divided into observation and control groups(95 patients per group).The control group received escitalopram oxalate 10mg once a day for eight weeks.In addition,the observation group was also given HBO therapy,once a day,five times a week,for eight weeks.The Montgomery Depression Rating Scale(MADRS),National Institutes of Health Stroke Scale(NIHSS),hypersensitive C-reactive protein,tumor necrosis factor(TNF)-α,and fasting glucose levels were compared.RESULTS There were no significant differences in age,sex,or depression course between the groups(P>0.05).After HBO treatment,MADRS scores in both groups decreased significantly(14.3±5.2),and were significantly lower in the control group(18.1±3.5).After HBO treatment,NIHSS scores in both groups decreased significantly,and scores in the observation group(12.2±4.0)decreased more than in the control group(16.1±3.4),the difference was statistically significant(P<0.001).The levels of hypersensitive C-reactive protein and TNF-αin both groups were significantly decreased,and the observation group was significantly lower than the control group(P<0.001).Fasting blood glucose levels in both groups decreased significantly,and those in the observation group decreased more(8.02±1.10)than in the control group(9.26±1.04),with statistical significance(t=-7.994,P<0.001).CONCLUSION HBO therapy can significantly improve depressive symptoms and neurological dysfunction in patients with PSD,and reduce the levels of hypersensitive C-reactive protein,TNF-αand fasting blood glucose.展开更多
Shuxuetong injection composed of leech(Hirudo nipponica Whitman) and earthworm(Pheretima aspergillum) has been used for the clinical treatment of acute stroke for many years in China. However, the precise neuroprotect...Shuxuetong injection composed of leech(Hirudo nipponica Whitman) and earthworm(Pheretima aspergillum) has been used for the clinical treatment of acute stroke for many years in China. However, the precise neuroprotective mechanism of Shuxuetong injection remains poorly understood. Here, cerebral microvascular endothelial cells(bEnd.3) were incubated in glucose-free Dulbecco's modified Eagle's medium containing 95% N_2/5% CO_2 for 6 hours, followed by high-glucose medium containing 95% O_2 and 5% CO_2 for 18 hours to establish an oxygen-glucose deprivation/reperfusion model. This in vitro cell model was administered Shuxuetong injection at 1/32, 1/64, and 1/128 concentrations(diluted 32-, 64-, and 128-times). Cell Counting Kit-8 assay was used to evaluate cell viability. A fluorescence method was used to measure lactate dehydrogenase, and a fluorescence microplate reader used to detect intracellular reactive oxygen species. A fluorescent probe was also used to measure mitochondrial superoxide production. A cell resistance meter was used to measure transepithelial resistance and examine integrity of monolayer cells. The fluorescein isothiocyanate-dextran test was performed to examine blood-brain barrier permeability. Real-time reverse transcription polymerase chain reaction was performed to analyze mRNA expression levels of tumor necrosis factor alpha, interleukin-1β, interleukin-6, and inducible nitric oxide synthase. Western blot assay was performed to analyze expression of caspase-3, intercellular adhesion molecule 1, vascular cell adhesion molecule 1, occludin, vascular endothelial growth factor, cleaved caspase-3, B-cell lymphoma 2, phosphorylated extracellular signal-regulated protein kinase, extracellular signal-regulated protein kinase, nuclear factor-κB p65, I kappa B alpha, phosphorylated I kappa B alpha, I kappa B kinase, phosphorylated I kappa B kinase, claudin-5, and zonula occludens-1. Our results show that Shuxuetong injection increases bEnd.3 cell viability and B-cell lymphoma 2 expression, reduces cleaved caspase-3 expression, inhibits production of reactive oxygen species and mitochondrial superoxide, suppresses expression of tumor necrosis factor alpha, interleukin-1β, interleukin-6, inducible nitric oxide synthase mRNA, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1, markedly increases transepithelial resistance, decreases blood-brain barrier permeability, upregulates claudin-5, occludin, and zonula occludens-1 expression, reduces nuclear factor-κB p65 and vascular endothelial growth factor expression, and reduces I kappa B alpha, extracellular signal-regulated protein kinase 1/2, and I kappa B kinase phosphorylation levels. Overall, these findings suggest that Shuxuetong injection has protective effects on brain microvascular endothelial cells after oxygen-glucose deprivation/reperfusion. Moreover, its protective effect is associated with reduction of mitochondrial superoxide production, inhibition of the inflammatory response, and inhibition of vascular endothelial growth factor, extracellular signal-regulated protein kinase 1/2, and the nuclear factor-κB p65 signaling pathway.展开更多
AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cel...AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cell EC undergoing chemoradiotherapy were used to generate SMART,conventionally-fractionated three-dimensional conformal radiotherapy(3DCRT)and intensity-modulated radiation therapy(cf-IMRT)plans,respectively.The gross target volume(GTV)of the esophagus,positive regional lymph nodes(LN),and suspected lymph nodes(LN±)were contoured for each patient.The clinical target volume(CTV)was delineated with 2-cm longitudinal and 0.5-to 1.0-cm radial margins with respect to the GTV and with 0.5-cm uniform margins for LN and LN(±).For the SMART plans,there were two planning target volumes(PTVs):PTV66=(GTV+LN)+0.5 cm and PTV54=CTV+0.5 cm.For the 3DCRT and cfIMRT plans,there was only a single PTV:PTV60=CTV+0.5 cm.The prescribed dose for the SMART plans was 66 Gy/30 F to PTV66 and 54 Gy/30 F to PTV54.The dose prescription to the PTV60 for both the 3DCRT and cf-IMRT plans was set to 60 Gy/30 F.All the plans were generated on the Eclipse 10.0 treatment planning system.Fulfillment of the dose criteria for the PTVs received the highest priority,followed by the spinal cord,heart,and lungs.The dose-volume histograms were compared.RESULTS:Clinically acceptable plans were achieved for all the SMART,cf-IMRT,and 3DCRT plans.Compared with the 3DCRT plans,the SMART plans increased the dose delivered to the primary tumor(66Gy vs 60 Gy),with improved sparing of normal tissues in all patients.The Dmax of the spinal cord,V20 of the lungs,and Dmean and V50 of the heart for the SMART and 3DCRT plans were as follows:38.5±2.0 vs 44.7±0.8(P=0.002),17.1±4.0 vs 25.8±5.0(P=0.000),14.4±7.5 vs 21.4±11.1(P=0.000),and 4.9±3.4vs 12.9±7.6(P=0.000),respectively.In contrast to the cf-IMRT plans,the SMART plans permitted a simultaneous dose escalation(6 Gy)to the primary tumor while demonstrating a significant trend of a lower irradiation dose to all organs at risk except the spinal cord,for which no significant difference was found.CONCLUSION:SMART offers the potential for a 6Gy simultaneous escalation in the irradiation dose delivered to the primary tumor of EC and improves the sparing of normal tissues.展开更多
Diamond reinforced copper(Cu/diamond) composites were prepared by pressure infiltration for their application in thermal management where both high thermal conductivity and low coefficient of thermal expansion(CTE) ar...Diamond reinforced copper(Cu/diamond) composites were prepared by pressure infiltration for their application in thermal management where both high thermal conductivity and low coefficient of thermal expansion(CTE) are important.They were characterized by the microstructure and thermal properties as a function of boron content,which is used for matrix-alloying to increase the interfacial bonding between the diamond and copper.The obtained composites show high thermal conductivity(>660 W/(m·K)) and low CET(<7.4×10-6 K-1) due to the formation of the B13C2 layer at the diamond-copper interface,which greatly strengthens the interfacial bonding.Thermal property measurements indicate that in the Cu-B/diamond composites,the thermal conductivity and the CTE show a different variation trend as a function of boron content,which is attributed to the thickness and distribution of the interfacial carbide layer.The CTE behavior of the present composites can be well described by Kerner's model,especially for the composites with 0.5wt% B.展开更多
基金National Natural Science Foundation of China(Grant Nos.52075111,51775123)Fundamental Research Funds for the Central Universities(Grant No.3072022JC0701)。
文摘To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure,a quasiperiodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise reduction.The arrangement of the elastic support element is determined by the equivalent periodic distance and quasi-periodic coefficient.In this paper,a dynamic model of skin in a fluid environment is established.The influence of equivalent periodic distance and quasi-periodic coefficient on flow stability is investigated.The results suggest that arranging the elastic support elements in accordance with the quasi-periodic law can effectively enhance flow stability.Meanwhile,the hydrodynamic noise calculation results demonstrate that the skin exhibits excellent noise reduction performance,with reductions of 10 dB in the streamwise direction,11 dB in the spanwise direction,and 10 dB in the normal direction.The results also demonstrate that the stability analysis method can serve as a diagnostic tool for flow fields and guide the design of noise reduction structures.
基金supported by the National Natural Science Foundation of China,No.81173592National Science and Technology Major Project of the Ministry of Science and Technology of China,No.2011ZX09201-201,2012ZX09101201-004,2012ZX09101202,NCET-130935,2013ZX09201020+1 种基金Tianjin Municipal Applied Basic Research and Cutting-Edge Technology Research Scheme of China,No.14JCYBJC28900Program for Innovation Team Training in Universities in Tianjin,No.TD12-5035
文摘Danhong injection(DHI),a Chinese Materia Medica standardized product extracted from Radix Salviae miltiorrhizae and Flos Carthami tinctorii,is widely used in China for treating acute ischemic stroke.In the present study,we explored the neuroprotective efficacy of DHI in a rat model of temporary middle cerebral artery occlusion,and evaluated the potential mechanisms underlying its effects.Pretreatment with DHI(0.9 and 1.8 mL/kg)resulted in a significantly smaller infarct volume and better neurological scores than pretreatment with saline.Furthermore,DHI significantly reduced the permeability of the blood-brain barrier,increased occludin protein expression and decreased neutrophil infiltration,as well as profoundly suppressing the upregulation of matrix metallopeptidase-9 expression seen in rats that had received vehicle.Matrix metallopeptidase-2 expression was not affected by ischemia or DHI.Moreover,DHI(1.8 mL/kg)administered 3 hours after the onset of ischemia also improved neurological scores and reduced infarct size.Our results indicate that the neuroprotective efficacy of DHI in a rat model of cerebral ischemia-reperfusion injury is mediated by a protective effect on the blood-brain barrier and the reversal of neutrophil infiltration.
基金National Natural Science Foundation of China,Grant/Award Number:52064049Key National Natural Science Foundation of Yunnan Province,Grant/Award Numbers:2018FA028,2019FY003023+1 种基金International Joint Research Center for Advanced Energy Materials of Yunnan Province,Grant/Award Number:202003AE140001Key Laboratory of Solid State Ions for Green Energy of Yunnan University,Grant/Award Number:2019。
文摘A solid-state electrolyte(SSE),which is a solid ionic conductor and electroninsulating material,is known to play a crucial role in adapting a lithium metal anode to a high-capacity cathode in a solid-state battery.Among the various SSEs,the single Li-ion conductor has advantages in terms of enhancing the ion conductivity,eliminating interfacial side reactions,and broadening the electrochemical window.Covalent organic frameworks(COFs)are optimal platforms for achieving single Li-ion conduction behavior because of wellordered one-dimensional channels and precise chemical modification features.Herein,we study in depth three types of Li-carboxylate COFs(denoted LiOOC-COFn,n=1,2,and 3)as single Li-ion conducting SSEs.Benefiting from well-ordered directional ion channels,the single Li-ion conductor LiOOC-COF3 shows an exceptional ion conductivity of 1.36×10^(-5) S cm^(-1) at room temperature and a high transference number of 0.91.Moreover,it shows excellent electrochemical performance with long-term cycling,high-capacity output,and no dendrites in the quasi-solid-state organic battery,with the organic small molecule cyclohexanehexone(C_(6)O_(6))as the cathode and the Li metal as the anode,and enables effectively avoiding dissolution of the organic electrode by the liquid electrolyte.
基金financial support provided by the National Natural Science Foundation of China(52064049)the Key National Natural Science Foundation of Yunnan Province(2018FA028 and 2019FY003023)+2 种基金International Joint Research Center for Advanced Energy Materials of Yunnan Province(202003AE140001)Key Laboratory of Solid State Ions for Green Energy of Yunnan University(2019)the Analysis and Measurements Center of Yunnan University for the sample testing service.
文摘Lithium metal batteries(LMBs)have attracted wide attentions because of their high theoretical specific capacity and low electrochemical potential.However,the growth of lithium dendrites seriously affects the practical application of LMBs.Thus,the lithium-philic carbonyl and carboxy dualgroup-modified covalent organic framework(COF-COOH)is designed to coat the polypropylene(PP)separator(COF-COOH@PP separator),realizing the regulation of ion transport and uniform lithium deposition.The plentiful and negative charge sites in the COF-COOH can suppress the diffusion of the freely movable lithium salt anion by the electrostatic interaction.Density functional theory(DFT)calculations demonstrate that the COF-COOH possesses the function of anchoring anion and desolvation.Consequently,the Li^(+)transference number(0.7),ion conductivity(0.64 mS cm^(-1)),and desolvating of Li^(+)are obviously improved by using the COF-COOH@PP separator.The modified Li-Li symmetric battery delivers stable cycle for more than 1000 h and lower voltage hysteresis(0.02 V).This dendrite-free deposition strategy holds great promise for practical application of Li metal anodes.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61571018 and 61531003).
文摘Micrometric-thin cells(MCs)with alkali vapor atoms have been valuable for research and applications of hyperfine Zeeman splitting and atomic magnetometers under strong magnetic fields.We theoretically and experimentally study the saturated absorption spectra using a 100-μm cesium MC,where the pump and probe beams are linearly polarized with mutually perpendicular polarizations,and the magnetic field is along the pump beam.Because of the distinctive thin chamber of the MC,crossover spectral lines in saturated absorption spectra are largely suppressed leading to clear splittings of hyperfine Zeeman transitions in experiments,and the effect of spatial magnetic field gradient is expected to be reduced.A calculation method is proposed to achieve good agreements between theoretical calculations and experimental results.This method successfully explains the suppression of crossover lines in MCs,as well as the effects of magnetic field direction,propagation and polarization directions of the pump/probe beam on saturated absorption spectrum.The saturated absorption spectrum with suppressed crossover lines is used for laser frequency stabilization,which may provide the potential value of MCs for high spatial resolution strong-field magnetometry with high sensitivity.
文摘BACKGROUND In patients with post-stroke depression(PSD)in diabetes,the situation may be more complex,requiring simultaneous treatment of blood glucose,depressive symptoms,and neurological dysfunction.Hyperbaric oxygen(HBO)therapy can improve tissue oxygen content and improve the situation of ischemia and hypoxia,thus playing a role in protecting brain cells and restoring the function of brain cells.However,there are few studies on HBO therapy for patients with PSD.This study explores the clinical efficacy of such therapy for stroke complicated with depression and diabetes mellitus,and to provide reference and basis for clinical treatment and development through the application of relevant rating scales and laboratory test indicators.AIM To evaluate the clinical effects of HBO therapy on patients with diabetes with PSD.METHODS A total of 190 diabetic patients with PSD were randomly divided into observation and control groups(95 patients per group).The control group received escitalopram oxalate 10mg once a day for eight weeks.In addition,the observation group was also given HBO therapy,once a day,five times a week,for eight weeks.The Montgomery Depression Rating Scale(MADRS),National Institutes of Health Stroke Scale(NIHSS),hypersensitive C-reactive protein,tumor necrosis factor(TNF)-α,and fasting glucose levels were compared.RESULTS There were no significant differences in age,sex,or depression course between the groups(P>0.05).After HBO treatment,MADRS scores in both groups decreased significantly(14.3±5.2),and were significantly lower in the control group(18.1±3.5).After HBO treatment,NIHSS scores in both groups decreased significantly,and scores in the observation group(12.2±4.0)decreased more than in the control group(16.1±3.4),the difference was statistically significant(P<0.001).The levels of hypersensitive C-reactive protein and TNF-αin both groups were significantly decreased,and the observation group was significantly lower than the control group(P<0.001).Fasting blood glucose levels in both groups decreased significantly,and those in the observation group decreased more(8.02±1.10)than in the control group(9.26±1.04),with statistical significance(t=-7.994,P<0.001).CONCLUSION HBO therapy can significantly improve depressive symptoms and neurological dysfunction in patients with PSD,and reduce the levels of hypersensitive C-reactive protein,TNF-αand fasting blood glucose.
基金supported in part by the National Natural Science Foundation of China,No.81573644(to LMH),81573733(to SWX)the Tianjin 131 Innovative Team Project,China(to HW)+5 种基金the National Major Science and Technology Project of China,No.2012ZX09101201-004(to SWX)the Science and Technology Plan Project of Tianjin of China,No.16PTSYJC00120(to LMH)the Applied Foundation and Frontier Technology Research Program of Tianjin of China(General Project),No.14JCYBJC28900(to SXW)the National International Science and Technology Cooperation Project of China,No.2015DFA30430(to HW)the Key Program of the Natural Science Foundation of Tianjin of China,No.16ICZDJC36300(to HW)the Scientific Research and Technology Development Plan Project of Guangxi Zhuang Autonomous Region of China,No.14125008-2-5(to SXW)
文摘Shuxuetong injection composed of leech(Hirudo nipponica Whitman) and earthworm(Pheretima aspergillum) has been used for the clinical treatment of acute stroke for many years in China. However, the precise neuroprotective mechanism of Shuxuetong injection remains poorly understood. Here, cerebral microvascular endothelial cells(bEnd.3) were incubated in glucose-free Dulbecco's modified Eagle's medium containing 95% N_2/5% CO_2 for 6 hours, followed by high-glucose medium containing 95% O_2 and 5% CO_2 for 18 hours to establish an oxygen-glucose deprivation/reperfusion model. This in vitro cell model was administered Shuxuetong injection at 1/32, 1/64, and 1/128 concentrations(diluted 32-, 64-, and 128-times). Cell Counting Kit-8 assay was used to evaluate cell viability. A fluorescence method was used to measure lactate dehydrogenase, and a fluorescence microplate reader used to detect intracellular reactive oxygen species. A fluorescent probe was also used to measure mitochondrial superoxide production. A cell resistance meter was used to measure transepithelial resistance and examine integrity of monolayer cells. The fluorescein isothiocyanate-dextran test was performed to examine blood-brain barrier permeability. Real-time reverse transcription polymerase chain reaction was performed to analyze mRNA expression levels of tumor necrosis factor alpha, interleukin-1β, interleukin-6, and inducible nitric oxide synthase. Western blot assay was performed to analyze expression of caspase-3, intercellular adhesion molecule 1, vascular cell adhesion molecule 1, occludin, vascular endothelial growth factor, cleaved caspase-3, B-cell lymphoma 2, phosphorylated extracellular signal-regulated protein kinase, extracellular signal-regulated protein kinase, nuclear factor-κB p65, I kappa B alpha, phosphorylated I kappa B alpha, I kappa B kinase, phosphorylated I kappa B kinase, claudin-5, and zonula occludens-1. Our results show that Shuxuetong injection increases bEnd.3 cell viability and B-cell lymphoma 2 expression, reduces cleaved caspase-3 expression, inhibits production of reactive oxygen species and mitochondrial superoxide, suppresses expression of tumor necrosis factor alpha, interleukin-1β, interleukin-6, inducible nitric oxide synthase mRNA, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1, markedly increases transepithelial resistance, decreases blood-brain barrier permeability, upregulates claudin-5, occludin, and zonula occludens-1 expression, reduces nuclear factor-κB p65 and vascular endothelial growth factor expression, and reduces I kappa B alpha, extracellular signal-regulated protein kinase 1/2, and I kappa B kinase phosphorylation levels. Overall, these findings suggest that Shuxuetong injection has protective effects on brain microvascular endothelial cells after oxygen-glucose deprivation/reperfusion. Moreover, its protective effect is associated with reduction of mitochondrial superoxide production, inhibition of the inflammatory response, and inhibition of vascular endothelial growth factor, extracellular signal-regulated protein kinase 1/2, and the nuclear factor-κB p65 signaling pathway.
基金Supported by Shantou University Medical College Clinical Research Enhancement Initiative,and Research and Travel Grants from the Science and Technology Key Project of Shantou City,China,2012,No.2012-165-131
文摘AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cell EC undergoing chemoradiotherapy were used to generate SMART,conventionally-fractionated three-dimensional conformal radiotherapy(3DCRT)and intensity-modulated radiation therapy(cf-IMRT)plans,respectively.The gross target volume(GTV)of the esophagus,positive regional lymph nodes(LN),and suspected lymph nodes(LN±)were contoured for each patient.The clinical target volume(CTV)was delineated with 2-cm longitudinal and 0.5-to 1.0-cm radial margins with respect to the GTV and with 0.5-cm uniform margins for LN and LN(±).For the SMART plans,there were two planning target volumes(PTVs):PTV66=(GTV+LN)+0.5 cm and PTV54=CTV+0.5 cm.For the 3DCRT and cfIMRT plans,there was only a single PTV:PTV60=CTV+0.5 cm.The prescribed dose for the SMART plans was 66 Gy/30 F to PTV66 and 54 Gy/30 F to PTV54.The dose prescription to the PTV60 for both the 3DCRT and cf-IMRT plans was set to 60 Gy/30 F.All the plans were generated on the Eclipse 10.0 treatment planning system.Fulfillment of the dose criteria for the PTVs received the highest priority,followed by the spinal cord,heart,and lungs.The dose-volume histograms were compared.RESULTS:Clinically acceptable plans were achieved for all the SMART,cf-IMRT,and 3DCRT plans.Compared with the 3DCRT plans,the SMART plans increased the dose delivered to the primary tumor(66Gy vs 60 Gy),with improved sparing of normal tissues in all patients.The Dmax of the spinal cord,V20 of the lungs,and Dmean and V50 of the heart for the SMART and 3DCRT plans were as follows:38.5±2.0 vs 44.7±0.8(P=0.002),17.1±4.0 vs 25.8±5.0(P=0.000),14.4±7.5 vs 21.4±11.1(P=0.000),and 4.9±3.4vs 12.9±7.6(P=0.000),respectively.In contrast to the cf-IMRT plans,the SMART plans permitted a simultaneous dose escalation(6 Gy)to the primary tumor while demonstrating a significant trend of a lower irradiation dose to all organs at risk except the spinal cord,for which no significant difference was found.CONCLUSION:SMART offers the potential for a 6Gy simultaneous escalation in the irradiation dose delivered to the primary tumor of EC and improves the sparing of normal tissues.
基金supported by the National Natural Science Foundation of China (No.50971020)the National High-Tech Research and Development Program of China (No.2008AA03Z505)
文摘Diamond reinforced copper(Cu/diamond) composites were prepared by pressure infiltration for their application in thermal management where both high thermal conductivity and low coefficient of thermal expansion(CTE) are important.They were characterized by the microstructure and thermal properties as a function of boron content,which is used for matrix-alloying to increase the interfacial bonding between the diamond and copper.The obtained composites show high thermal conductivity(>660 W/(m·K)) and low CET(<7.4×10-6 K-1) due to the formation of the B13C2 layer at the diamond-copper interface,which greatly strengthens the interfacial bonding.Thermal property measurements indicate that in the Cu-B/diamond composites,the thermal conductivity and the CTE show a different variation trend as a function of boron content,which is attributed to the thickness and distribution of the interfacial carbide layer.The CTE behavior of the present composites can be well described by Kerner's model,especially for the composites with 0.5wt% B.
