Although a considerable increase in our knowledge concerning the importance of metabolic adjustments to unfavorable growth conditions has been recently provided, relatively little is known about the adjustments which ...Although a considerable increase in our knowledge concerning the importance of metabolic adjustments to unfavorable growth conditions has been recently provided, relatively little is known about the adjustments which occur in response to fluctuation in environmental factors. Evaluating the metabolic adjustments occurring under changing environmental conditions thus offers a good opportunity to increase our current understanding of the crosstalk between the major pathways which are affected by such conditions. To this end, plants growing under normal conditions were transferred to different light and temperature conditions which were anticipated to affect （amongst other processes） the rates of photosynthesis and photorespiration and characterized at the physiological, molecular, and metabolic levels following this transition. Our results revealed similar behavior in response to both treatments and imply a tight connec- tivity of photorespiration with the major pathways of plant metabolism. They further highlight that the majority of the regulation of these pathways is not mediated at the level of transcription but that leaf metabolism is rather pre-poised to adapt to changes in these input parameters.展开更多
Glutaraldehyde(Glut)is an extensively used sterilant and fixative for the crosslinking of natural soft tissue biomaterials like bovine pericardium(BP)to provide stability and is required for its application in vivo.Th...Glutaraldehyde(Glut)is an extensively used sterilant and fixative for the crosslinking of natural soft tissue biomaterials like bovine pericardium(BP)to provide stability and is required for its application in vivo.There is plenty of debate around the reaction mechanism of Glut with natural biomaterials.Differential scanning calorimetry(DSC)is a commonly used technique that is typically used to measure the thermal profile of polymers.However,a variation known as quasi-isothermal modulated differential scanning calorimetry(QiMDSC)has been utilised for the analysis of polymorphic transformations in both the pharmaceutical and food industries.This communication will address QiMDSC as a method for analysing soft tissue biomaterials and their crosslinking mechanisms and how it can be applied to other biomaterial applications.展开更多
Fluctuating stress on the implanted coronary stents within cardiac cycle is an important mechanism of fatigue fracture,which is associated with in-stent restenosis and stent thrombosis.We developed a novel computation...Fluctuating stress on the implanted coronary stents within cardiac cycle is an important mechanism of fatigue fracture,which is associated with in-stent restenosis and stent thrombosis.We developed a novel computational modelling to calculate the dynamic stress of stents based on the time sequence angiography immediately after treatment.Two groups of patient-specific cases(one same stent design treated in 4 different coronary arteries and one same artery actually/virtually implanted one stent with 3 different designs)were performed the dynamic stress analysis by this computational modelling and subsequently assessed the fatigue fracture risk by Goodman method.The motion of target arteries significantly impacts on distribution of the stress and the risk of stent fracture,particularly in the site of hinge motion.Both the location of stent stress concentration in the obtuse marginal artery and the“unsafe”region in the inverse fatigue safety factor contour co-registered with the position of complete transverse fracture 13 months later after implantation.Three stents with different designs had the same location of highest stress concentration at the hinge motion site of the actually/virtually treated artery.Higher strength stent materials are significantly lower the risk of stent fracture rather than stent designs.This new computational modelling might be a useful tool in assessment of fracture risk of the implanted stent and in optimizing new design of dedicated stent treated specific coronary arteries and mechanical properties in vivo of bioresorbable scaffold during degradation process.展开更多
文摘Although a considerable increase in our knowledge concerning the importance of metabolic adjustments to unfavorable growth conditions has been recently provided, relatively little is known about the adjustments which occur in response to fluctuation in environmental factors. Evaluating the metabolic adjustments occurring under changing environmental conditions thus offers a good opportunity to increase our current understanding of the crosstalk between the major pathways which are affected by such conditions. To this end, plants growing under normal conditions were transferred to different light and temperature conditions which were anticipated to affect （amongst other processes） the rates of photosynthesis and photorespiration and characterized at the physiological, molecular, and metabolic levels following this transition. Our results revealed similar behavior in response to both treatments and imply a tight connec- tivity of photorespiration with the major pathways of plant metabolism. They further highlight that the majority of the regulation of these pathways is not mediated at the level of transcription but that leaf metabolism is rather pre-poised to adapt to changes in these input parameters.
基金supported by both Boston Scientific Galway[grant number:Higher Education].
文摘Glutaraldehyde(Glut)is an extensively used sterilant and fixative for the crosslinking of natural soft tissue biomaterials like bovine pericardium(BP)to provide stability and is required for its application in vivo.There is plenty of debate around the reaction mechanism of Glut with natural biomaterials.Differential scanning calorimetry(DSC)is a commonly used technique that is typically used to measure the thermal profile of polymers.However,a variation known as quasi-isothermal modulated differential scanning calorimetry(QiMDSC)has been utilised for the analysis of polymorphic transformations in both the pharmaceutical and food industries.This communication will address QiMDSC as a method for analysing soft tissue biomaterials and their crosslinking mechanisms and how it can be applied to other biomaterial applications.
文摘Fluctuating stress on the implanted coronary stents within cardiac cycle is an important mechanism of fatigue fracture,which is associated with in-stent restenosis and stent thrombosis.We developed a novel computational modelling to calculate the dynamic stress of stents based on the time sequence angiography immediately after treatment.Two groups of patient-specific cases(one same stent design treated in 4 different coronary arteries and one same artery actually/virtually implanted one stent with 3 different designs)were performed the dynamic stress analysis by this computational modelling and subsequently assessed the fatigue fracture risk by Goodman method.The motion of target arteries significantly impacts on distribution of the stress and the risk of stent fracture,particularly in the site of hinge motion.Both the location of stent stress concentration in the obtuse marginal artery and the“unsafe”region in the inverse fatigue safety factor contour co-registered with the position of complete transverse fracture 13 months later after implantation.Three stents with different designs had the same location of highest stress concentration at the hinge motion site of the actually/virtually treated artery.Higher strength stent materials are significantly lower the risk of stent fracture rather than stent designs.This new computational modelling might be a useful tool in assessment of fracture risk of the implanted stent and in optimizing new design of dedicated stent treated specific coronary arteries and mechanical properties in vivo of bioresorbable scaffold during degradation process.
